diff --git a/libgo/MERGE b/libgo/MERGE
index ddfb006..85703d6 100644
--- a/libgo/MERGE
+++ b/libgo/MERGE
@@ -1,4 +1,4 @@
-352996a381701cfa0c16e8de29cbde8f3922182f
+c8aec4095e089ff6ac50d18e97c3f46561f14f48
 
 The first line of this file holds the git revision number of the
 last merge done from the master library sources.
diff --git a/libgo/Makefile.am b/libgo/Makefile.am
index 9800d20..2376130 100644
--- a/libgo/Makefile.am
+++ b/libgo/Makefile.am
@@ -117,6 +117,8 @@
 toolexeclib_LIBRARIES = libgobegin.a libgolibbegin.a
 endif
 
+noinst_LIBRARIES = libgotool.a
+
 toolexeclibgo_DATA = \
 	bufio.gox \
 	bytes.gox \
@@ -299,6 +301,7 @@
 
 toolexeclibgomath_DATA = \
 	math/big.gox \
+	math/bits.gox \
 	math/cmplx.gox \
 	math/rand.gox
 
@@ -534,6 +537,21 @@
 	$(SHELL) $(srcdir)/mvifdiff.sh tmp-sigtab.go sigtab.go
 	$(STAMP) $@
 
+GCCGO_INSTALL_NAME := $(shell echo gccgo|sed '$(program_transform_name)')
+GCC_INSTALL_NAME := $(shell echo gcc|sed '$(program_transform_name)')
+GXX_INSTALL_NAME := $(shell echo g++|sed '$(program_transform_name)')
+
+zdefaultcc.go: s-zdefaultcc; @true
+s-zdefaultcc: Makefile
+	echo 'package cfg' > zdefaultcc.go.tmp
+	echo >> zdefaultcc.go.tmp
+	echo 'const DefaultGCCGO = "$(bindir)/$(GCCGO_INSTALL_NAME)"' >> zdefaultcc.go.tmp
+	echo 'const DefaultCC = "$(GCC_INSTALL_NAME)"' >> zdefaultcc.go.tmp
+	echo 'const DefaultCXX = "$(GXX_INSTALL_NAME)"' >> zdefaultcc.go.tmp
+	echo 'const DefaultPkgConfig = "pkg-config"' >> zdefaultcc.go.tmp
+	$(SHELL) $(srcdir)/../move-if-change zdefaultcc.go.tmp zdefaultcc.go
+	$(STAMP) $@ 
+
 # _Complex_lock and _Reader_lock are Go translations of some AIX system
 # types and should not be exported back to C
 # semt is a Go translation of the C type sem_t; it fails to convert on
@@ -555,13 +573,13 @@
 	rm -f runtime.inc.tmp2 runtime.inc.tmp3
 	$(STAMP) $@
 
-noinst_DATA = zstdpkglist.go
+noinst_DATA = zstdpkglist.go zdefaultcc.go
 
 # Generate the list of go std packages that were included in libgo
 zstdpkglist.go: s-zstdpkglist; @true
 s-zstdpkglist: Makefile
 	rm -f zstdpkglist.go.tmp
-	echo 'package main' > zstdpkglist.go.tmp
+	echo 'package load' > zstdpkglist.go.tmp
 	echo "" >> zstdpkglist.go.tmp
 	echo 'var stdpkg = map[string]bool{' >> zstdpkglist.go.tmp
 	echo $(libgo_go_objs) 'unsafe.lo' 'runtime/cgo.lo' | sed 's|[a-z0-9_/]*_c\.lo||g' | sed 's|\([a-z0-9_/]*\)\.lo|"\1": true,|g' >> zstdpkglist.go.tmp
@@ -660,7 +678,6 @@
 	archive/zip \
 	bufio \
 	bytes \
-	cmd/internal/browser \
 	compress/bzip2 \
 	compress/flate \
 	compress/gzip \
@@ -724,6 +741,7 @@
 	go/importer \
 	go/internal/gccgoimporter \
 	go/internal/gcimporter \
+	go/internal/srcimporter \
 	go/parser \
 	go/printer \
 	go/scanner \
@@ -736,7 +754,10 @@
 	golang_org/x/net/http2/hpack \
 	golang_org/x/net/idna \
 	golang_org/x/net/lex/httplex \
+	golang_org/x/net/proxy \
+	golang_org/x/text/secure/bidirule \
 	golang_org/x/text/transform \
+	golang_org/x/text/unicode/bidi \
 	golang_org/x/text/unicode/norm \
 	golang_org/x/text/width \
 	hash \
@@ -756,7 +777,7 @@
 	image/png \
 	index/suffixarray \
 	internal/nettrace \
-	internal/pprof/profile \
+	internal/poll \
 	internal/race \
 	internal/singleflight \
 	internal/syscall/unix \
@@ -768,6 +789,7 @@
 	log/syslog \
 	math \
 	math/big \
+	math/bits \
 	math/cmplx \
 	math/rand \
 	mime \
@@ -804,7 +826,7 @@
 	runtime/internal/atomic \
 	runtime/internal/sys \
 	runtime/pprof \
-	runtime/pprof/internal/protopprof \
+	runtime/pprof/internal/profile \
 	runtime/trace \
 	sort \
 	strconv \
@@ -871,6 +893,37 @@
 
 libgolibbegin_a_CFLAGS = $(AM_CFLAGS) -fPIC
 
+GOTOOL_PACKAGES = \
+	cmd/go/internal/base \
+	cmd/go/internal/bug \
+	cmd/go/internal/buildid \
+	cmd/go/internal/cfg \
+	cmd/go/internal/clean \
+	cmd/go/internal/cmdflag \
+	cmd/go/internal/doc \
+	cmd/go/internal/envcmd \
+	cmd/go/internal/fix \
+	cmd/go/internal/fmtcmd \
+	cmd/go/internal/generate \
+	cmd/go/internal/get \
+	cmd/go/internal/help \
+	cmd/go/internal/list \
+	cmd/go/internal/load \
+	cmd/go/internal/run \
+	cmd/go/internal/str \
+	cmd/go/internal/test \
+	cmd/go/internal/tool \
+	cmd/go/internal/version \
+	cmd/go/internal/vet \
+	cmd/go/internal/web \
+	cmd/go/internal/work \
+	cmd/internal/browser \
+	cmd/internal/objabi
+
+libgotool_a_SOURCES =
+libgotool_a_DEPENDENCIES = $(addsuffix .lo,$(GOTOOL_PACKAGES))
+libgotool_a_LIBADD = $(addsuffix .o,$(GOTOOL_PACKAGES))
+
 # Make sure runtime.inc is built before compiling any .c file.
 $(libgo_la_OBJECTS): runtime.inc
 $(libgo_llgo_la_OBJECTS): runtime.inc
@@ -925,7 +978,7 @@
 CHECK = \
 	GC="$(GOC) $(GOCFLAGS) $($(subst /,_,$@)_GOCFLAGS) -L `${PWD_COMMAND}` -L `${PWD_COMMAND}`/.libs"; \
 	export GC; \
-	GOLIBS="$(MATH_LIBS) $(NET_LIBS) $(LIBS)"; \
+	GOLIBS="$(extra_check_libs_$(subst /,_,$(@D))) $(MATH_LIBS) $(NET_LIBS) $(LIBS)"; \
 	export GOLIBS; \
 	RUNTESTFLAGS="$(RUNTESTFLAGS)"; \
 	export RUNTESTFLAGS; \
@@ -985,7 +1038,8 @@
 	$(toolexeclibgotesting_DATA) \
 	$(toolexeclibgotext_DATA) \
 	$(toolexeclibgotexttemplate_DATA) \
-	$(toolexeclibgounicode_DATA)
+	$(toolexeclibgounicode_DATA) \
+	$(noinst_LIBRARIES)
 
 if GOC_IS_LLGO
 CHECK_DEPS += libgo-llgo.la libgobegin-llgo.a
@@ -1025,6 +1079,7 @@
 # This line expands PACKAGE_template once for each package name listed
 # in $(PACKAGES).
 $(foreach package,$(PACKAGES),$(eval $(call PACKAGE_template,$(package))))
+$(foreach package,$(GOTOOL_PACKAGES),$(eval $(call PACKAGE_template,$(package))))
 
 # Pass -ffp-contract=off, or 386-specific options, when building the
 # math package.  MATH_FLAG is defined in configure.ac.
@@ -1066,6 +1121,17 @@
 extra_go_files_runtime_internal_sys = version.go
 runtime/internal/sys.lo.dep: $(extra_go_files_runtime_internal_sys)
 
+extra_go_files_cmd_go_internal_cfg = zdefaultcc.go
+cmd/go/internal/cfg.lo.dep: $(extra_go_files_cmd_go_internal_cfg)
+
+extra_go_files_cmd_go_internal_load = zstdpkglist.go
+cmd/go/internal/load.lo.dep: $(extra_go_files_cmd_go_internal_load)
+
+extra_check_libs_cmd_go_internal_generate = $(abs_builddir)/libgotool.a
+extra_check_libs_cmd_go_internal_get = $(abs_builddir)/libgotool.a
+extra_check_libs_cmd_go_internal_load = $(abs_builddir)/libgotool.a
+extra_check_libs_cmd_go_internal_work = $(abs_builddir)/libgotool.a
+
 # FIXME: The following C files may as well move to the runtime
 # directory and be treated like other C files.
 
@@ -1177,6 +1243,11 @@
 	unicode/check \
 	archive/tar/check \
 	archive/zip/check \
+	cmd/go/internal/generate/check \
+	cmd/go/internal/get/check \
+	cmd/go/internal/load/check \
+	cmd/go/internal/work/check \
+	cmd/internal/objabi/check \
 	compress/bzip2/check \
 	compress/flate/check \
 	compress/gzip/check \
@@ -1230,6 +1301,7 @@
 	go/format/check \
 	go/internal/gcimporter/check \
 	go/internal/gccgoimporter/check \
+	go/internal/srcimporter/check \
 	go/parser/check \
 	go/printer/check \
 	go/scanner/check \
@@ -1243,6 +1315,7 @@
 	golang_org/x/net/idna/check \
 	golang_org/x/net/lex/httplex/check \
 	$(golang_org_x_net_lif_check) \
+	golang_org/x/net/proxy/check \
 	$(golang_org_x_net_route_check) \
 	hash/adler32/check \
 	hash/crc32/check \
@@ -1253,12 +1326,13 @@
 	image/jpeg/check \
 	image/png/check \
 	index/suffixarray/check \
-	internal/pprof/profile/check \
+	internal/poll/check \
 	internal/singleflight/check \
 	internal/trace/check \
 	io/ioutil/check \
 	log/syslog/check \
 	math/big/check \
+	math/bits/check \
 	math/cmplx/check \
 	math/rand/check \
 	mime/multipart/check \
@@ -1287,7 +1361,7 @@
 	runtime/internal/atomic/check \
 	runtime/internal/sys/check \
 	runtime/pprof/check \
-	runtime/pprof/internal/protopprof/check \
+	runtime/pprof/internal/profile/check \
 	runtime/trace/check \
 	sync/atomic/check \
 	text/scanner/check \
@@ -1413,7 +1487,7 @@
 	find . -name '*-testsum' -print | xargs rm -f
 	find . -name '*-testlog' -print | xargs rm -f
 
-CLEANFILES = *.go *.c s-version libgo.sum libgo.log runtime.inc
+CLEANFILES = *.go *.c s-* libgo.sum libgo.log runtime.inc
 
 clean-local:
 	find . -name '*.la' -print | xargs $(LIBTOOL) --mode=clean rm -f
diff --git a/libgo/Makefile.in b/libgo/Makefile.in
index 9a2bd47..5f7adb2 100644
--- a/libgo/Makefile.in
+++ b/libgo/Makefile.in
@@ -155,7 +155,7 @@
 	"$(DESTDIR)$(toolexeclibgotextdir)" \
 	"$(DESTDIR)$(toolexeclibgotexttemplatedir)" \
 	"$(DESTDIR)$(toolexeclibgounicodedir)"
-LIBRARIES = $(toolexeclib_LIBRARIES)
+LIBRARIES = $(noinst_LIBRARIES) $(toolexeclib_LIBRARIES)
 ARFLAGS = cru
 libgobegin_llgo_a_AR = $(AR) $(ARFLAGS)
 libgobegin_llgo_a_LIBADD =
@@ -169,6 +169,9 @@
 libgolibbegin_a_LIBADD =
 am_libgolibbegin_a_OBJECTS = libgolibbegin_a-go-libmain.$(OBJEXT)
 libgolibbegin_a_OBJECTS = $(am_libgolibbegin_a_OBJECTS)
+libgotool_a_AR = $(AR) $(ARFLAGS)
+am_libgotool_a_OBJECTS =
+libgotool_a_OBJECTS = $(am_libgotool_a_OBJECTS)
 LTLIBRARIES = $(toolexeclib_LTLIBRARIES)
 @LIBGO_IS_LINUX_TRUE@am__DEPENDENCIES_1 = syscall/clone_linux.lo
 am__DEPENDENCIES_2 = $(addsuffix .lo,$(PACKAGES)) bytes/index.lo \
@@ -229,8 +232,8 @@
 	--mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) \
 	$(LDFLAGS) -o $@
 SOURCES = $(libgobegin_llgo_a_SOURCES) $(libgobegin_a_SOURCES) \
-	$(libgolibbegin_a_SOURCES) $(libgo_llgo_la_SOURCES) \
-	$(libgo_la_SOURCES)
+	$(libgolibbegin_a_SOURCES) $(libgotool_a_SOURCES) \
+	$(libgo_llgo_la_SOURCES) $(libgo_la_SOURCES)
 MULTISRCTOP = 
 MULTIBUILDTOP = 
 MULTIDIRS = 
@@ -518,6 +521,7 @@
 @GOC_IS_LLGO_TRUE@toolexeclib_LTLIBRARIES = libgo-llgo.la
 @GOC_IS_LLGO_FALSE@toolexeclib_LIBRARIES = libgobegin.a libgolibbegin.a
 @GOC_IS_LLGO_TRUE@toolexeclib_LIBRARIES = libgobegin-llgo.a
+noinst_LIBRARIES = libgotool.a
 toolexeclibgo_DATA = \
 	bufio.gox \
 	bytes.gox \
@@ -681,6 +685,7 @@
 toolexeclibgomathdir = $(toolexeclibgodir)/math
 toolexeclibgomath_DATA = \
 	math/big.gox \
+	math/bits.gox \
 	math/cmplx.gox \
 	math/rand.gox
 
@@ -809,7 +814,10 @@
 	$(rtems_task_variable_add_file) \
 	$(runtime_getncpu_file)
 
-noinst_DATA = zstdpkglist.go
+GCCGO_INSTALL_NAME := $(shell echo gccgo|sed '$(program_transform_name)')
+GCC_INSTALL_NAME := $(shell echo gcc|sed '$(program_transform_name)')
+GXX_INSTALL_NAME := $(shell echo g++|sed '$(program_transform_name)')
+noinst_DATA = zstdpkglist.go zdefaultcc.go
 @LIBGO_IS_LINUX_FALSE@syscall_epoll_file = 
 @LIBGO_IS_LINUX_TRUE@syscall_epoll_file = epoll.go
 SYSINFO_FLAGS = \
@@ -823,7 +831,6 @@
 	archive/zip \
 	bufio \
 	bytes \
-	cmd/internal/browser \
 	compress/bzip2 \
 	compress/flate \
 	compress/gzip \
@@ -887,6 +894,7 @@
 	go/importer \
 	go/internal/gccgoimporter \
 	go/internal/gcimporter \
+	go/internal/srcimporter \
 	go/parser \
 	go/printer \
 	go/scanner \
@@ -899,7 +907,10 @@
 	golang_org/x/net/http2/hpack \
 	golang_org/x/net/idna \
 	golang_org/x/net/lex/httplex \
+	golang_org/x/net/proxy \
+	golang_org/x/text/secure/bidirule \
 	golang_org/x/text/transform \
+	golang_org/x/text/unicode/bidi \
 	golang_org/x/text/unicode/norm \
 	golang_org/x/text/width \
 	hash \
@@ -919,7 +930,7 @@
 	image/png \
 	index/suffixarray \
 	internal/nettrace \
-	internal/pprof/profile \
+	internal/poll \
 	internal/race \
 	internal/singleflight \
 	internal/syscall/unix \
@@ -931,6 +942,7 @@
 	log/syslog \
 	math \
 	math/big \
+	math/bits \
 	math/cmplx \
 	math/rand \
 	mime \
@@ -967,7 +979,7 @@
 	runtime/internal/atomic \
 	runtime/internal/sys \
 	runtime/pprof \
-	runtime/pprof/internal/protopprof \
+	runtime/pprof/internal/profile \
 	runtime/trace \
 	sort \
 	strconv \
@@ -1031,6 +1043,36 @@
 	runtime/go-libmain.c
 
 libgolibbegin_a_CFLAGS = $(AM_CFLAGS) -fPIC
+GOTOOL_PACKAGES = \
+	cmd/go/internal/base \
+	cmd/go/internal/bug \
+	cmd/go/internal/buildid \
+	cmd/go/internal/cfg \
+	cmd/go/internal/clean \
+	cmd/go/internal/cmdflag \
+	cmd/go/internal/doc \
+	cmd/go/internal/envcmd \
+	cmd/go/internal/fix \
+	cmd/go/internal/fmtcmd \
+	cmd/go/internal/generate \
+	cmd/go/internal/get \
+	cmd/go/internal/help \
+	cmd/go/internal/list \
+	cmd/go/internal/load \
+	cmd/go/internal/run \
+	cmd/go/internal/str \
+	cmd/go/internal/test \
+	cmd/go/internal/tool \
+	cmd/go/internal/version \
+	cmd/go/internal/vet \
+	cmd/go/internal/web \
+	cmd/go/internal/work \
+	cmd/internal/browser \
+	cmd/internal/objabi
+
+libgotool_a_SOURCES = 
+libgotool_a_DEPENDENCIES = $(addsuffix .lo,$(GOTOOL_PACKAGES))
+libgotool_a_LIBADD = $(addsuffix .o,$(GOTOOL_PACKAGES))
 LTLDFLAGS = $(shell $(SHELL) $(top_srcdir)/../libtool-ldflags $(LDFLAGS))
 AM_GOCFLAGS = $(STRINGOPS_FLAG) $(GO_SPLIT_STACK)
 GOCOMPILE = $(GOC) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_GOCFLAGS) $(GOCFLAGS)
@@ -1078,7 +1120,7 @@
 CHECK = \
 	GC="$(GOC) $(GOCFLAGS) $($(subst /,_,$@)_GOCFLAGS) -L `${PWD_COMMAND}` -L `${PWD_COMMAND}`/.libs"; \
 	export GC; \
-	GOLIBS="$(MATH_LIBS) $(NET_LIBS) $(LIBS)"; \
+	GOLIBS="$(extra_check_libs_$(subst /,_,$(@D))) $(MATH_LIBS) $(NET_LIBS) $(LIBS)"; \
 	export GOLIBS; \
 	RUNTESTFLAGS="$(RUNTESTFLAGS)"; \
 	export RUNTESTFLAGS; \
@@ -1125,7 +1167,8 @@
 	$(toolexeclibgorpc_DATA) $(toolexeclibgoruntime_DATA) \
 	$(toolexeclibgosync_DATA) $(toolexeclibgotesting_DATA) \
 	$(toolexeclibgotext_DATA) $(toolexeclibgotexttemplate_DATA) \
-	$(toolexeclibgounicode_DATA) $(am__append_3) $(am__append_4)
+	$(toolexeclibgounicode_DATA) $(noinst_LIBRARIES) \
+	$(am__append_3) $(am__append_4)
 
 # Pass -ffp-contract=off, or 386-specific options, when building the
 # math package.  MATH_FLAG is defined in configure.ac.
@@ -1160,6 +1203,12 @@
 # Also use -fno-inline to get better results from the memory profiler.
 runtime_pprof_check_GOCFLAGS = -static-libgo -fno-inline
 extra_go_files_runtime_internal_sys = version.go
+extra_go_files_cmd_go_internal_cfg = zdefaultcc.go
+extra_go_files_cmd_go_internal_load = zstdpkglist.go
+extra_check_libs_cmd_go_internal_generate = $(abs_builddir)/libgotool.a
+extra_check_libs_cmd_go_internal_get = $(abs_builddir)/libgotool.a
+extra_check_libs_cmd_go_internal_load = $(abs_builddir)/libgotool.a
+extra_check_libs_cmd_go_internal_work = $(abs_builddir)/libgotool.a
 @HAVE_STAT_TIMESPEC_FALSE@@LIBGO_IS_SOLARIS_TRUE@matchargs_os = 
 
 # Solaris 12 changed the type of fields in struct stat.
@@ -1207,6 +1256,11 @@
 	unicode/check \
 	archive/tar/check \
 	archive/zip/check \
+	cmd/go/internal/generate/check \
+	cmd/go/internal/get/check \
+	cmd/go/internal/load/check \
+	cmd/go/internal/work/check \
+	cmd/internal/objabi/check \
 	compress/bzip2/check \
 	compress/flate/check \
 	compress/gzip/check \
@@ -1260,6 +1314,7 @@
 	go/format/check \
 	go/internal/gcimporter/check \
 	go/internal/gccgoimporter/check \
+	go/internal/srcimporter/check \
 	go/parser/check \
 	go/printer/check \
 	go/scanner/check \
@@ -1273,6 +1328,7 @@
 	golang_org/x/net/idna/check \
 	golang_org/x/net/lex/httplex/check \
 	$(golang_org_x_net_lif_check) \
+	golang_org/x/net/proxy/check \
 	$(golang_org_x_net_route_check) \
 	hash/adler32/check \
 	hash/crc32/check \
@@ -1283,12 +1339,13 @@
 	image/jpeg/check \
 	image/png/check \
 	index/suffixarray/check \
-	internal/pprof/profile/check \
+	internal/poll/check \
 	internal/singleflight/check \
 	internal/trace/check \
 	io/ioutil/check \
 	log/syslog/check \
 	math/big/check \
+	math/bits/check \
 	math/cmplx/check \
 	math/rand/check \
 	mime/multipart/check \
@@ -1317,7 +1374,7 @@
 	runtime/internal/atomic/check \
 	runtime/internal/sys/check \
 	runtime/pprof/check \
-	runtime/pprof/internal/protopprof/check \
+	runtime/pprof/internal/profile/check \
 	runtime/trace/check \
 	sync/atomic/check \
 	text/scanner/check \
@@ -1335,7 +1392,7 @@
 	libgo.head libgo.sum.sep libgo.log.sep libgo.var \
 	libcalls-list runtime.inc runtime.inc.tmp2 runtime.inc.tmp3
 
-CLEANFILES = *.go *.c s-version libgo.sum libgo.log runtime.inc
+CLEANFILES = *.go *.c s-* libgo.sum libgo.log runtime.inc
 all: config.h
 	$(MAKE) $(AM_MAKEFLAGS) all-recursive
 
@@ -1390,6 +1447,9 @@
 
 distclean-hdr:
 	-rm -f config.h stamp-h1
+
+clean-noinstLIBRARIES:
+	-test -z "$(noinst_LIBRARIES)" || rm -f $(noinst_LIBRARIES)
 install-toolexeclibLIBRARIES: $(toolexeclib_LIBRARIES)
 	@$(NORMAL_INSTALL)
 	@list='$(toolexeclib_LIBRARIES)'; test -n "$(toolexeclibdir)" || list=; \
@@ -1433,6 +1493,10 @@
 	-rm -f libgolibbegin.a
 	$(libgolibbegin_a_AR) libgolibbegin.a $(libgolibbegin_a_OBJECTS) $(libgolibbegin_a_LIBADD)
 	$(RANLIB) libgolibbegin.a
+libgotool.a: $(libgotool_a_OBJECTS) $(libgotool_a_DEPENDENCIES) $(EXTRA_libgotool_a_DEPENDENCIES) 
+	-rm -f libgotool.a
+	$(libgotool_a_AR) libgotool.a $(libgotool_a_OBJECTS) $(libgotool_a_LIBADD)
+	$(RANLIB) libgotool.a
 install-toolexeclibLTLIBRARIES: $(toolexeclib_LTLIBRARIES)
 	@$(NORMAL_INSTALL)
 	@list='$(toolexeclib_LTLIBRARIES)'; test -n "$(toolexeclibdir)" || list=; \
@@ -2797,8 +2861,8 @@
 clean: clean-multi clean-recursive
 
 clean-am: clean-generic clean-libtool clean-local \
-	clean-toolexeclibLIBRARIES clean-toolexeclibLTLIBRARIES \
-	mostlyclean-am
+	clean-noinstLIBRARIES clean-toolexeclibLIBRARIES \
+	clean-toolexeclibLTLIBRARIES mostlyclean-am
 
 distclean: distclean-multi distclean-recursive
 	-rm -f $(am__CONFIG_DISTCLEAN_FILES)
@@ -2931,17 +2995,18 @@
 .PHONY: $(RECURSIVE_CLEAN_TARGETS) $(RECURSIVE_TARGETS) CTAGS GTAGS \
 	all all-am all-multi am--refresh check check-am clean \
 	clean-generic clean-libtool clean-local clean-multi \
-	clean-toolexeclibLIBRARIES clean-toolexeclibLTLIBRARIES ctags \
-	ctags-recursive distclean distclean-compile distclean-generic \
-	distclean-hdr distclean-libtool distclean-local \
-	distclean-multi distclean-tags dvi dvi-am html html-am info \
-	info-am install install-am install-data install-data-am \
-	install-dvi install-dvi-am install-exec install-exec-am \
-	install-html install-html-am install-info install-info-am \
-	install-man install-multi install-pdf install-pdf-am \
-	install-ps install-ps-am install-strip \
-	install-toolexeclibLIBRARIES install-toolexeclibLTLIBRARIES \
-	install-toolexeclibgoDATA install-toolexeclibgoarchiveDATA \
+	clean-noinstLIBRARIES clean-toolexeclibLIBRARIES \
+	clean-toolexeclibLTLIBRARIES ctags ctags-recursive distclean \
+	distclean-compile distclean-generic distclean-hdr \
+	distclean-libtool distclean-local distclean-multi \
+	distclean-tags dvi dvi-am html html-am info info-am install \
+	install-am install-data install-data-am install-dvi \
+	install-dvi-am install-exec install-exec-am install-html \
+	install-html-am install-info install-info-am install-man \
+	install-multi install-pdf install-pdf-am install-ps \
+	install-ps-am install-strip install-toolexeclibLIBRARIES \
+	install-toolexeclibLTLIBRARIES install-toolexeclibgoDATA \
+	install-toolexeclibgoarchiveDATA \
 	install-toolexeclibgocompressDATA \
 	install-toolexeclibgocontainerDATA \
 	install-toolexeclibgocryptoDATA \
@@ -3069,6 +3134,17 @@
 	$(SHELL) $(srcdir)/mvifdiff.sh tmp-sigtab.go sigtab.go
 	$(STAMP) $@
 
+zdefaultcc.go: s-zdefaultcc; @true
+s-zdefaultcc: Makefile
+	echo 'package cfg' > zdefaultcc.go.tmp
+	echo >> zdefaultcc.go.tmp
+	echo 'const DefaultGCCGO = "$(bindir)/$(GCCGO_INSTALL_NAME)"' >> zdefaultcc.go.tmp
+	echo 'const DefaultCC = "$(GCC_INSTALL_NAME)"' >> zdefaultcc.go.tmp
+	echo 'const DefaultCXX = "$(GXX_INSTALL_NAME)"' >> zdefaultcc.go.tmp
+	echo 'const DefaultPkgConfig = "pkg-config"' >> zdefaultcc.go.tmp
+	$(SHELL) $(srcdir)/../move-if-change zdefaultcc.go.tmp zdefaultcc.go
+	$(STAMP) $@ 
+
 # _Complex_lock and _Reader_lock are Go translations of some AIX system
 # types and should not be exported back to C
 # semt is a Go translation of the C type sem_t; it fails to convert on
@@ -3094,7 +3170,7 @@
 zstdpkglist.go: s-zstdpkglist; @true
 s-zstdpkglist: Makefile
 	rm -f zstdpkglist.go.tmp
-	echo 'package main' > zstdpkglist.go.tmp
+	echo 'package load' > zstdpkglist.go.tmp
 	echo "" >> zstdpkglist.go.tmp
 	echo 'var stdpkg = map[string]bool{' >> zstdpkglist.go.tmp
 	echo $(libgo_go_objs) 'unsafe.lo' 'runtime/cgo.lo' | sed 's|[a-z0-9_/]*_c\.lo||g' | sed 's|\([a-z0-9_/]*\)\.lo|"\1": true,|g' >> zstdpkglist.go.tmp
@@ -3211,9 +3287,12 @@
 # This line expands PACKAGE_template once for each package name listed
 # in $(PACKAGES).
 $(foreach package,$(PACKAGES),$(eval $(call PACKAGE_template,$(package))))
+$(foreach package,$(GOTOOL_PACKAGES),$(eval $(call PACKAGE_template,$(package))))
 runtime.lo.dep: $(extra_go_files_runtime)
 syscall.lo.dep: $(extra_go_files_syscall)
 runtime/internal/sys.lo.dep: $(extra_go_files_runtime_internal_sys)
+cmd/go/internal/cfg.lo.dep: $(extra_go_files_cmd_go_internal_cfg)
+cmd/go/internal/load.lo.dep: $(extra_go_files_cmd_go_internal_load)
 
 # FIXME: The following C files may as well move to the runtime
 # directory and be treated like other C files.
diff --git a/libgo/VERSION b/libgo/VERSION
index b38ce77..6d1d72f 100644
--- a/libgo/VERSION
+++ b/libgo/VERSION
@@ -1 +1 @@
-go1.8.3
+go1.9
diff --git a/libgo/configure b/libgo/configure
index 3b0d0d2..1e5e41b 100755
--- a/libgo/configure
+++ b/libgo/configure
@@ -2494,7 +2494,7 @@
 ac_config_headers="$ac_config_headers config.h"
 
 
-libtool_VERSION=11:0:0
+libtool_VERSION=12:0:0
 
 
 # Default to --enable-multilib
diff --git a/libgo/configure.ac b/libgo/configure.ac
index 80ad3df..4bfe169 100644
--- a/libgo/configure.ac
+++ b/libgo/configure.ac
@@ -11,7 +11,7 @@
 AC_CONFIG_SRCDIR(Makefile.am)
 AC_CONFIG_HEADER(config.h)
 
-libtool_VERSION=11:0:0
+libtool_VERSION=12:0:0
 AC_SUBST(libtool_VERSION)
 
 AM_ENABLE_MULTILIB(, ..)
diff --git a/libgo/go/archive/tar/common.go b/libgo/go/archive/tar/common.go
index d2ae66d..d49c5c3 100644
--- a/libgo/go/archive/tar/common.go
+++ b/libgo/go/archive/tar/common.go
@@ -158,11 +158,15 @@
 // sysStat, if non-nil, populates h from system-dependent fields of fi.
 var sysStat func(fi os.FileInfo, h *Header) error
 
-// Mode constants from the tar spec.
 const (
-	c_ISUID  = 04000   // Set uid
-	c_ISGID  = 02000   // Set gid
-	c_ISVTX  = 01000   // Save text (sticky bit)
+	// Mode constants from the USTAR spec:
+	// See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06
+	c_ISUID = 04000 // Set uid
+	c_ISGID = 02000 // Set gid
+	c_ISVTX = 01000 // Save text (sticky bit)
+
+	// Common Unix mode constants; these are not defined in any common tar standard.
+	// Header.FileInfo understands these, but FileInfoHeader will never produce these.
 	c_ISDIR  = 040000  // Directory
 	c_ISFIFO = 010000  // FIFO
 	c_ISREG  = 0100000 // Regular file
@@ -208,30 +212,24 @@
 	}
 	switch {
 	case fm.IsRegular():
-		h.Mode |= c_ISREG
 		h.Typeflag = TypeReg
 		h.Size = fi.Size()
 	case fi.IsDir():
 		h.Typeflag = TypeDir
-		h.Mode |= c_ISDIR
 		h.Name += "/"
 	case fm&os.ModeSymlink != 0:
 		h.Typeflag = TypeSymlink
-		h.Mode |= c_ISLNK
 		h.Linkname = link
 	case fm&os.ModeDevice != 0:
 		if fm&os.ModeCharDevice != 0 {
-			h.Mode |= c_ISCHR
 			h.Typeflag = TypeChar
 		} else {
-			h.Mode |= c_ISBLK
 			h.Typeflag = TypeBlock
 		}
 	case fm&os.ModeNamedPipe != 0:
 		h.Typeflag = TypeFifo
-		h.Mode |= c_ISFIFO
 	case fm&os.ModeSocket != 0:
-		h.Mode |= c_ISSOCK
+		return nil, fmt.Errorf("archive/tar: sockets not supported")
 	default:
 		return nil, fmt.Errorf("archive/tar: unknown file mode %v", fm)
 	}
diff --git a/libgo/go/archive/tar/tar_test.go b/libgo/go/archive/tar/tar_test.go
index cf8337c..fb7a9dc 100644
--- a/libgo/go/archive/tar/tar_test.go
+++ b/libgo/go/archive/tar/tar_test.go
@@ -6,9 +6,11 @@
 
 import (
 	"bytes"
+	"internal/testenv"
 	"io/ioutil"
 	"os"
 	"path"
+	"path/filepath"
 	"reflect"
 	"strings"
 	"testing"
@@ -27,7 +29,7 @@
 	if g, e := h.Name, "small.txt"; g != e {
 		t.Errorf("Name = %q; want %q", g, e)
 	}
-	if g, e := h.Mode, int64(fi.Mode().Perm())|c_ISREG; g != e {
+	if g, e := h.Mode, int64(fi.Mode().Perm()); g != e {
 		t.Errorf("Mode = %#o; want %#o", g, e)
 	}
 	if g, e := h.Size, int64(5); g != e {
@@ -55,7 +57,7 @@
 		t.Errorf("Name = %q; want %q", g, e)
 	}
 	// Ignoring c_ISGID for golang.org/issue/4867
-	if g, e := h.Mode&^c_ISGID, int64(fi.Mode().Perm())|c_ISDIR; g != e {
+	if g, e := h.Mode&^c_ISGID, int64(fi.Mode().Perm()); g != e {
 		t.Errorf("Mode = %#o; want %#o", g, e)
 	}
 	if g, e := h.Size, int64(0); g != e {
@@ -67,40 +69,56 @@
 }
 
 func TestFileInfoHeaderSymlink(t *testing.T) {
-	h, err := FileInfoHeader(symlink{}, "some-target")
+	testenv.MustHaveSymlink(t)
+
+	tmpdir, err := ioutil.TempDir("", "TestFileInfoHeaderSymlink")
 	if err != nil {
 		t.Fatal(err)
 	}
-	if g, e := h.Name, "some-symlink"; g != e {
+	defer os.RemoveAll(tmpdir)
+
+	link := filepath.Join(tmpdir, "link")
+	target := tmpdir
+	err = os.Symlink(target, link)
+	if err != nil {
+		t.Fatal(err)
+	}
+	fi, err := os.Lstat(link)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	h, err := FileInfoHeader(fi, target)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if g, e := h.Name, fi.Name(); g != e {
 		t.Errorf("Name = %q; want %q", g, e)
 	}
-	if g, e := h.Linkname, "some-target"; g != e {
+	if g, e := h.Linkname, target; g != e {
 		t.Errorf("Linkname = %q; want %q", g, e)
 	}
+	if g, e := h.Typeflag, byte(TypeSymlink); g != e {
+		t.Errorf("Typeflag = %v; want %v", g, e)
+	}
 }
 
-type symlink struct{}
-
-func (symlink) Name() string       { return "some-symlink" }
-func (symlink) Size() int64        { return 0 }
-func (symlink) Mode() os.FileMode  { return os.ModeSymlink }
-func (symlink) ModTime() time.Time { return time.Time{} }
-func (symlink) IsDir() bool        { return false }
-func (symlink) Sys() interface{}   { return nil }
-
 func TestRoundTrip(t *testing.T) {
 	data := []byte("some file contents")
 
 	var b bytes.Buffer
 	tw := NewWriter(&b)
 	hdr := &Header{
-		Name:    "file.txt",
-		Uid:     1 << 21, // too big for 8 octal digits
-		Size:    int64(len(data)),
-		ModTime: time.Now(),
+		Name: "file.txt",
+		Uid:  1 << 21, // too big for 8 octal digits
+		Size: int64(len(data)),
+		// AddDate to strip monotonic clock reading,
+		// and Round to discard sub-second precision,
+		// both of which are not included in the tar header
+		// and would otherwise break the round-trip check
+		// below.
+		ModTime: time.Now().AddDate(0, 0, 0).Round(1 * time.Second),
 	}
-	// tar only supports second precision.
-	hdr.ModTime = hdr.ModTime.Add(-time.Duration(hdr.ModTime.Nanosecond()) * time.Nanosecond)
 	if err := tw.WriteHeader(hdr); err != nil {
 		t.Fatalf("tw.WriteHeader: %v", err)
 	}
@@ -139,7 +157,7 @@
 		// regular file.
 		h: &Header{
 			Name:     "test.txt",
-			Mode:     0644 | c_ISREG,
+			Mode:     0644,
 			Size:     12,
 			ModTime:  time.Unix(1360600916, 0),
 			Typeflag: TypeReg,
@@ -149,7 +167,7 @@
 		// symbolic link.
 		h: &Header{
 			Name:     "link.txt",
-			Mode:     0777 | c_ISLNK,
+			Mode:     0777,
 			Size:     0,
 			ModTime:  time.Unix(1360600852, 0),
 			Typeflag: TypeSymlink,
@@ -159,7 +177,7 @@
 		// character device node.
 		h: &Header{
 			Name:     "dev/null",
-			Mode:     0666 | c_ISCHR,
+			Mode:     0666,
 			Size:     0,
 			ModTime:  time.Unix(1360578951, 0),
 			Typeflag: TypeChar,
@@ -169,7 +187,7 @@
 		// block device node.
 		h: &Header{
 			Name:     "dev/sda",
-			Mode:     0660 | c_ISBLK,
+			Mode:     0660,
 			Size:     0,
 			ModTime:  time.Unix(1360578954, 0),
 			Typeflag: TypeBlock,
@@ -179,7 +197,7 @@
 		// directory.
 		h: &Header{
 			Name:     "dir/",
-			Mode:     0755 | c_ISDIR,
+			Mode:     0755,
 			Size:     0,
 			ModTime:  time.Unix(1360601116, 0),
 			Typeflag: TypeDir,
@@ -189,7 +207,7 @@
 		// fifo node.
 		h: &Header{
 			Name:     "dev/initctl",
-			Mode:     0600 | c_ISFIFO,
+			Mode:     0600,
 			Size:     0,
 			ModTime:  time.Unix(1360578949, 0),
 			Typeflag: TypeFifo,
@@ -199,7 +217,7 @@
 		// setuid.
 		h: &Header{
 			Name:     "bin/su",
-			Mode:     0755 | c_ISREG | c_ISUID,
+			Mode:     0755 | c_ISUID,
 			Size:     23232,
 			ModTime:  time.Unix(1355405093, 0),
 			Typeflag: TypeReg,
@@ -209,7 +227,7 @@
 		// setguid.
 		h: &Header{
 			Name:     "group.txt",
-			Mode:     0750 | c_ISREG | c_ISGID,
+			Mode:     0750 | c_ISGID,
 			Size:     0,
 			ModTime:  time.Unix(1360602346, 0),
 			Typeflag: TypeReg,
@@ -219,7 +237,7 @@
 		// sticky.
 		h: &Header{
 			Name:     "sticky.txt",
-			Mode:     0600 | c_ISREG | c_ISVTX,
+			Mode:     0600 | c_ISVTX,
 			Size:     7,
 			ModTime:  time.Unix(1360602540, 0),
 			Typeflag: TypeReg,
@@ -229,7 +247,7 @@
 		// hard link.
 		h: &Header{
 			Name:     "hard.txt",
-			Mode:     0644 | c_ISREG,
+			Mode:     0644,
 			Size:     0,
 			Linkname: "file.txt",
 			ModTime:  time.Unix(1360600916, 0),
@@ -240,7 +258,7 @@
 		// More information.
 		h: &Header{
 			Name:     "info.txt",
-			Mode:     0600 | c_ISREG,
+			Mode:     0600,
 			Size:     0,
 			Uid:      1000,
 			Gid:      1000,
diff --git a/libgo/go/archive/tar/testdata/ustar.issue12594.tar b/libgo/go/archive/tar/testdata/ustar.issue12594.tar
index c7910ae..50fcd00 100644
--- a/libgo/go/archive/tar/testdata/ustar.issue12594.tar
+++ b/libgo/go/archive/tar/testdata/ustar.issue12594.tar
Binary files differ
diff --git a/libgo/go/archive/tar/testdata/writer-big-long.tar b/libgo/go/archive/tar/testdata/writer-big-long.tar
index 52bd748..ea9bfa8 100644
--- a/libgo/go/archive/tar/testdata/writer-big-long.tar
+++ b/libgo/go/archive/tar/testdata/writer-big-long.tar
Binary files differ
diff --git a/libgo/go/archive/tar/writer.go b/libgo/go/archive/tar/writer.go
index 596fb8b..c51c243 100644
--- a/libgo/go/archive/tar/writer.go
+++ b/libgo/go/archive/tar/writer.go
@@ -121,9 +121,15 @@
 		needsPaxHeader := paxKeyword != paxNone && len(s) > len(b) || !isASCII(s)
 		if needsPaxHeader {
 			paxHeaders[paxKeyword] = s
-			return
 		}
-		f.formatString(b, s)
+
+		// Write string in a best-effort manner to satisfy readers that expect
+		// the field to be non-empty.
+		s = toASCII(s)
+		if len(s) > len(b) {
+			s = s[:len(b)]
+		}
+		f.formatString(b, s) // Should never error
 	}
 	var formatNumeric = func(b []byte, x int64, paxKeyword string) {
 		// Try octal first.
diff --git a/libgo/go/archive/zip/register.go b/libgo/go/archive/zip/register.go
index 2e76386..51e9c3e 100644
--- a/libgo/go/archive/zip/register.go
+++ b/libgo/go/archive/zip/register.go
@@ -103,51 +103,46 @@
 }
 
 var (
-	mu sync.RWMutex // guards compressor and decompressor maps
-
-	compressors = map[uint16]Compressor{
-		Store:   func(w io.Writer) (io.WriteCloser, error) { return &nopCloser{w}, nil },
-		Deflate: func(w io.Writer) (io.WriteCloser, error) { return newFlateWriter(w), nil },
-	}
-
-	decompressors = map[uint16]Decompressor{
-		Store:   ioutil.NopCloser,
-		Deflate: newFlateReader,
-	}
+	compressors   sync.Map // map[uint16]Compressor
+	decompressors sync.Map // map[uint16]Decompressor
 )
 
+func init() {
+	compressors.Store(Store, Compressor(func(w io.Writer) (io.WriteCloser, error) { return &nopCloser{w}, nil }))
+	compressors.Store(Deflate, Compressor(func(w io.Writer) (io.WriteCloser, error) { return newFlateWriter(w), nil }))
+
+	decompressors.Store(Store, Decompressor(ioutil.NopCloser))
+	decompressors.Store(Deflate, Decompressor(newFlateReader))
+}
+
 // RegisterDecompressor allows custom decompressors for a specified method ID.
 // The common methods Store and Deflate are built in.
 func RegisterDecompressor(method uint16, dcomp Decompressor) {
-	mu.Lock()
-	defer mu.Unlock()
-
-	if _, ok := decompressors[method]; ok {
+	if _, dup := decompressors.LoadOrStore(method, dcomp); dup {
 		panic("decompressor already registered")
 	}
-	decompressors[method] = dcomp
 }
 
 // RegisterCompressor registers custom compressors for a specified method ID.
 // The common methods Store and Deflate are built in.
 func RegisterCompressor(method uint16, comp Compressor) {
-	mu.Lock()
-	defer mu.Unlock()
-
-	if _, ok := compressors[method]; ok {
+	if _, dup := compressors.LoadOrStore(method, comp); dup {
 		panic("compressor already registered")
 	}
-	compressors[method] = comp
 }
 
 func compressor(method uint16) Compressor {
-	mu.RLock()
-	defer mu.RUnlock()
-	return compressors[method]
+	ci, ok := compressors.Load(method)
+	if !ok {
+		return nil
+	}
+	return ci.(Compressor)
 }
 
 func decompressor(method uint16) Decompressor {
-	mu.RLock()
-	defer mu.RUnlock()
-	return decompressors[method]
+	di, ok := decompressors.Load(method)
+	if !ok {
+		return nil
+	}
+	return di.(Decompressor)
 }
diff --git a/libgo/go/archive/zip/struct.go b/libgo/go/archive/zip/struct.go
index e92d02f..0be210e 100644
--- a/libgo/go/archive/zip/struct.go
+++ b/libgo/go/archive/zip/struct.go
@@ -5,7 +5,7 @@
 /*
 Package zip provides support for reading and writing ZIP archives.
 
-See: https://www.pkware.com/documents/casestudies/APPNOTE.TXT
+See: https://www.pkware.com/appnote
 
 This package does not support disk spanning.
 
diff --git a/libgo/go/archive/zip/writer.go b/libgo/go/archive/zip/writer.go
index 8940e25..9f4fcee 100644
--- a/libgo/go/archive/zip/writer.go
+++ b/libgo/go/archive/zip/writer.go
@@ -11,10 +11,9 @@
 	"hash"
 	"hash/crc32"
 	"io"
+	"unicode/utf8"
 )
 
-// TODO(adg): support zip file comments
-
 // Writer implements a zip file writer.
 type Writer struct {
 	cw          *countWriter
@@ -201,6 +200,20 @@
 	return w.CreateHeader(header)
 }
 
+func hasValidUTF8(s string) bool {
+	n := 0
+	for _, r := range s {
+		// By default, ZIP uses CP437, which is only identical to ASCII for the printable characters.
+		if r < 0x20 || r >= 0x7f {
+			if !utf8.ValidRune(r) {
+				return false
+			}
+			n++
+		}
+	}
+	return n > 0
+}
+
 // CreateHeader adds a file to the zip file using the provided FileHeader
 // for the file metadata.
 // It returns a Writer to which the file contents should be written.
@@ -221,6 +234,10 @@
 
 	fh.Flags |= 0x8 // we will write a data descriptor
 
+	if hasValidUTF8(fh.Name) || hasValidUTF8(fh.Comment) {
+		fh.Flags |= 0x800 // filename or comment have valid utf-8 string
+	}
+
 	fh.CreatorVersion = fh.CreatorVersion&0xff00 | zipVersion20 // preserve compatibility byte
 	fh.ReaderVersion = zipVersion20
 
diff --git a/libgo/go/archive/zip/writer_test.go b/libgo/go/archive/zip/writer_test.go
index 86841c7..92fb6ec 100644
--- a/libgo/go/archive/zip/writer_test.go
+++ b/libgo/go/archive/zip/writer_test.go
@@ -87,6 +87,69 @@
 	}
 }
 
+func TestWriterUTF8(t *testing.T) {
+	var utf8Tests = []struct {
+		name    string
+		comment string
+		expect  uint16
+	}{
+		{
+			name:    "hi, hello",
+			comment: "in the world",
+			expect:  0x8,
+		},
+		{
+			name:    "hi, こんにちわ",
+			comment: "in the world",
+			expect:  0x808,
+		},
+		{
+			name:    "hi, hello",
+			comment: "in the 世界",
+			expect:  0x808,
+		},
+		{
+			name:    "hi, こんにちわ",
+			comment: "in the 世界",
+			expect:  0x808,
+		},
+	}
+
+	// write a zip file
+	buf := new(bytes.Buffer)
+	w := NewWriter(buf)
+
+	for _, test := range utf8Tests {
+		h := &FileHeader{
+			Name:    test.name,
+			Comment: test.comment,
+			Method:  Deflate,
+		}
+		w, err := w.CreateHeader(h)
+		if err != nil {
+			t.Fatal(err)
+		}
+		w.Write([]byte{})
+	}
+
+	if err := w.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// read it back
+	r, err := NewReader(bytes.NewReader(buf.Bytes()), int64(buf.Len()))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for i, test := range utf8Tests {
+		got := r.File[i].Flags
+		t.Logf("name %v, comment %v", test.name, test.comment)
+		if got != test.expect {
+			t.Fatalf("Flags: got %v, want %v", got, test.expect)
+		}
+	}
+}
+
 func TestWriterOffset(t *testing.T) {
 	largeData := make([]byte, 1<<17)
 	for i := range largeData {
@@ -181,12 +244,11 @@
 }
 
 func BenchmarkCompressedZipGarbage(b *testing.B) {
-	b.ReportAllocs()
-	var buf bytes.Buffer
 	bigBuf := bytes.Repeat([]byte("a"), 1<<20)
-	for i := 0; i <= b.N; i++ {
+
+	runOnce := func(buf *bytes.Buffer) {
 		buf.Reset()
-		zw := NewWriter(&buf)
+		zw := NewWriter(buf)
 		for j := 0; j < 3; j++ {
 			w, _ := zw.CreateHeader(&FileHeader{
 				Name:   "foo",
@@ -195,11 +257,19 @@
 			w.Write(bigBuf)
 		}
 		zw.Close()
-		if i == 0 {
-			// Reset the timer after the first time through.
-			// This effectively discards the very large initial flate setup cost,
-			// as well as the initialization of bigBuf.
-			b.ResetTimer()
-		}
 	}
+
+	b.ReportAllocs()
+	// Run once and then reset the timer.
+	// This effectively discards the very large initial flate setup cost,
+	// as well as the initialization of bigBuf.
+	runOnce(&bytes.Buffer{})
+	b.ResetTimer()
+
+	b.RunParallel(func(pb *testing.PB) {
+		var buf bytes.Buffer
+		for pb.Next() {
+			runOnce(&buf)
+		}
+	})
 }
diff --git a/libgo/go/archive/zip/zip_test.go b/libgo/go/archive/zip/zip_test.go
index 57edb2c..18c2171 100644
--- a/libgo/go/archive/zip/zip_test.go
+++ b/libgo/go/archive/zip/zip_test.go
@@ -255,7 +255,7 @@
 	testZip64DirectoryRecordLength(buf, t)
 }
 
-// Tests that we generate a zip64 file if the the directory at offset
+// Tests that we generate a zip64 file if the directory at offset
 // 0xFFFFFFFF, but not before.
 func TestZip64DirectoryOffset(t *testing.T) {
 	if testing.Short() && race.Enabled {
@@ -681,6 +681,18 @@
 	}
 }
 
+func BenchmarkZip64TestSizes(b *testing.B) {
+	for _, size := range []int64{1 << 12, 1 << 20, 1 << 26} {
+		b.Run(fmt.Sprint(size), func(b *testing.B) {
+			b.RunParallel(func(pb *testing.PB) {
+				for pb.Next() {
+					testZip64(b, size)
+				}
+			})
+		})
+	}
+}
+
 func TestSuffixSaver(t *testing.T) {
 	const keep = 10
 	ss := &suffixSaver{keep: keep}
diff --git a/libgo/go/bufio/bufio.go b/libgo/go/bufio/bufio.go
index e1e8fb2..da94a25 100644
--- a/libgo/go/bufio/bufio.go
+++ b/libgo/go/bufio/bufio.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package bufio implements buffered I/O.  It wraps an io.Reader or io.Writer
+// Package bufio implements buffered I/O. It wraps an io.Reader or io.Writer
 // object, creating another object (Reader or Writer) that also implements
 // the interface but provides buffering and some help for textual I/O.
 package bufio
@@ -458,6 +458,7 @@
 }
 
 // WriteTo implements io.WriterTo.
+// This may make multiple calls to the Read method of the underlying Reader.
 func (b *Reader) WriteTo(w io.Writer) (n int64, err error) {
 	n, err = b.writeBuf(w)
 	if err != nil {
@@ -513,7 +514,7 @@
 
 // Writer implements buffering for an io.Writer object.
 // If an error occurs writing to a Writer, no more data will be
-// accepted and all subsequent writes will return the error.
+// accepted and all subsequent writes, and Flush, will return the error.
 // After all data has been written, the client should call the
 // Flush method to guarantee all data has been forwarded to
 // the underlying io.Writer.
diff --git a/libgo/go/bufio/scan_test.go b/libgo/go/bufio/scan_test.go
index 1bb1e88..2568225 100644
--- a/libgo/go/bufio/scan_test.go
+++ b/libgo/go/bufio/scan_test.go
@@ -169,7 +169,6 @@
 		}
 		buf.WriteByte('\n')
 	}
-	return
 }
 
 // Test the line splitter, including some carriage returns but no long lines.
diff --git a/libgo/go/builtin/builtin.go b/libgo/go/builtin/builtin.go
index 281de0b..1c7c041 100644
--- a/libgo/go/builtin/builtin.go
+++ b/libgo/go/builtin/builtin.go
@@ -85,11 +85,11 @@
 // byte is an alias for uint8 and is equivalent to uint8 in all ways. It is
 // used, by convention, to distinguish byte values from 8-bit unsigned
 // integer values.
-type byte byte
+type byte = uint8
 
 // rune is an alias for int32 and is equivalent to int32 in all ways. It is
 // used, by convention, to distinguish character values from integer values.
-type rune rune
+type rune = int32
 
 // iota is a predeclared identifier representing the untyped integer ordinal
 // number of the current const specification in a (usually parenthesized)
@@ -179,7 +179,7 @@
 //	Channel: The channel's buffer is initialized with the specified
 //	buffer capacity. If zero, or the size is omitted, the channel is
 //	unbuffered.
-func make(Type, size IntegerType) Type
+func make(t Type, size ...IntegerType) Type
 
 // The new built-in function allocates memory. The first argument is a type,
 // not a value, and the value returned is a pointer to a newly
diff --git a/libgo/go/bytes/buffer.go b/libgo/go/bytes/buffer.go
index 196419d..20e42bb 100644
--- a/libgo/go/bytes/buffer.go
+++ b/libgo/go/bytes/buffer.go
@@ -15,10 +15,15 @@
 // A Buffer is a variable-sized buffer of bytes with Read and Write methods.
 // The zero value for Buffer is an empty buffer ready to use.
 type Buffer struct {
-	buf       []byte   // contents are the bytes buf[off : len(buf)]
-	off       int      // read at &buf[off], write at &buf[len(buf)]
-	bootstrap [64]byte // memory to hold first slice; helps small buffers avoid allocation.
-	lastRead  readOp   // last read operation, so that Unread* can work correctly.
+	buf      []byte // contents are the bytes buf[off : len(buf)]
+	off      int    // read at &buf[off], write at &buf[len(buf)]
+	lastRead readOp // last read operation, so that Unread* can work correctly.
+	// FIXME: lastRead can fit in a single byte
+
+	// memory to hold first slice; helps small buffers avoid allocation.
+	// FIXME: it would be advisable to align Buffer to cachelines to avoid false
+	// sharing.
+	bootstrap [64]byte
 }
 
 // The readOp constants describe the last action performed on
@@ -68,13 +73,13 @@
 // but continues to use the same allocated storage.
 // It panics if n is negative or greater than the length of the buffer.
 func (b *Buffer) Truncate(n int) {
+	if n == 0 {
+		b.Reset()
+		return
+	}
 	b.lastRead = opInvalid
-	switch {
-	case n < 0 || n > b.Len():
+	if n < 0 || n > b.Len() {
 		panic("bytes.Buffer: truncation out of range")
-	case n == 0:
-		// Reuse buffer space.
-		b.off = 0
 	}
 	b.buf = b.buf[0 : b.off+n]
 }
@@ -82,7 +87,22 @@
 // Reset resets the buffer to be empty,
 // but it retains the underlying storage for use by future writes.
 // Reset is the same as Truncate(0).
-func (b *Buffer) Reset() { b.Truncate(0) }
+func (b *Buffer) Reset() {
+	b.buf = b.buf[:0]
+	b.off = 0
+	b.lastRead = opInvalid
+}
+
+// tryGrowByReslice is a inlineable version of grow for the fast-case where the
+// internal buffer only needs to be resliced.
+// It returns the index where bytes should be written and whether it succeeded.
+func (b *Buffer) tryGrowByReslice(n int) (int, bool) {
+	if l := len(b.buf); l+n <= cap(b.buf) {
+		b.buf = b.buf[:l+n]
+		return l, true
+	}
+	return 0, false
+}
 
 // grow grows the buffer to guarantee space for n more bytes.
 // It returns the index where bytes should be written.
@@ -91,29 +111,33 @@
 	m := b.Len()
 	// If buffer is empty, reset to recover space.
 	if m == 0 && b.off != 0 {
-		b.Truncate(0)
+		b.Reset()
 	}
-	if len(b.buf)+n > cap(b.buf) {
-		var buf []byte
-		if b.buf == nil && n <= len(b.bootstrap) {
-			buf = b.bootstrap[0:]
-		} else if m+n <= cap(b.buf)/2 {
-			// We can slide things down instead of allocating a new
-			// slice. We only need m+n <= cap(b.buf) to slide, but
-			// we instead let capacity get twice as large so we
-			// don't spend all our time copying.
-			copy(b.buf[:], b.buf[b.off:])
-			buf = b.buf[:m]
-		} else {
-			// not enough space anywhere
-			buf = makeSlice(2*cap(b.buf) + n)
-			copy(buf, b.buf[b.off:])
-		}
+	// Try to grow by means of a reslice.
+	if i, ok := b.tryGrowByReslice(n); ok {
+		return i
+	}
+	// Check if we can make use of bootstrap array.
+	if b.buf == nil && n <= len(b.bootstrap) {
+		b.buf = b.bootstrap[:n]
+		return 0
+	}
+	if m+n <= cap(b.buf)/2 {
+		// We can slide things down instead of allocating a new
+		// slice. We only need m+n <= cap(b.buf) to slide, but
+		// we instead let capacity get twice as large so we
+		// don't spend all our time copying.
+		copy(b.buf[:], b.buf[b.off:])
+	} else {
+		// Not enough space anywhere, we need to allocate.
+		buf := makeSlice(2*cap(b.buf) + n)
+		copy(buf, b.buf[b.off:])
 		b.buf = buf
-		b.off = 0
 	}
-	b.buf = b.buf[0 : b.off+m+n]
-	return b.off + m
+	// Restore b.off and len(b.buf).
+	b.off = 0
+	b.buf = b.buf[:m+n]
+	return m
 }
 
 // Grow grows the buffer's capacity, if necessary, to guarantee space for
@@ -134,7 +158,10 @@
 // buffer becomes too large, Write will panic with ErrTooLarge.
 func (b *Buffer) Write(p []byte) (n int, err error) {
 	b.lastRead = opInvalid
-	m := b.grow(len(p))
+	m, ok := b.tryGrowByReslice(len(p))
+	if !ok {
+		m = b.grow(len(p))
+	}
 	return copy(b.buf[m:], p), nil
 }
 
@@ -143,7 +170,10 @@
 // buffer becomes too large, WriteString will panic with ErrTooLarge.
 func (b *Buffer) WriteString(s string) (n int, err error) {
 	b.lastRead = opInvalid
-	m := b.grow(len(s))
+	m, ok := b.tryGrowByReslice(len(s))
+	if !ok {
+		m = b.grow(len(s))
+	}
 	return copy(b.buf[m:], s), nil
 }
 
@@ -161,7 +191,7 @@
 	b.lastRead = opInvalid
 	// If buffer is empty, reset to recover space.
 	if b.off >= len(b.buf) {
-		b.Truncate(0)
+		b.Reset()
 	}
 	for {
 		if free := cap(b.buf) - len(b.buf); free < MinRead {
@@ -225,7 +255,7 @@
 		}
 	}
 	// Buffer is now empty; reset.
-	b.Truncate(0)
+	b.Reset()
 	return
 }
 
@@ -235,7 +265,10 @@
 // ErrTooLarge.
 func (b *Buffer) WriteByte(c byte) error {
 	b.lastRead = opInvalid
-	m := b.grow(1)
+	m, ok := b.tryGrowByReslice(1)
+	if !ok {
+		m = b.grow(1)
+	}
 	b.buf[m] = c
 	return nil
 }
@@ -250,7 +283,10 @@
 		return 1, nil
 	}
 	b.lastRead = opInvalid
-	m := b.grow(utf8.UTFMax)
+	m, ok := b.tryGrowByReslice(utf8.UTFMax)
+	if !ok {
+		m = b.grow(utf8.UTFMax)
+	}
 	n = utf8.EncodeRune(b.buf[m:m+utf8.UTFMax], r)
 	b.buf = b.buf[:m+n]
 	return n, nil
@@ -264,7 +300,7 @@
 	b.lastRead = opInvalid
 	if b.off >= len(b.buf) {
 		// Buffer is empty, reset to recover space.
-		b.Truncate(0)
+		b.Reset()
 		if len(p) == 0 {
 			return
 		}
@@ -302,7 +338,7 @@
 	b.lastRead = opInvalid
 	if b.off >= len(b.buf) {
 		// Buffer is empty, reset to recover space.
-		b.Truncate(0)
+		b.Reset()
 		return 0, io.EOF
 	}
 	c := b.buf[b.off]
@@ -320,7 +356,7 @@
 	b.lastRead = opInvalid
 	if b.off >= len(b.buf) {
 		// Buffer is empty, reset to recover space.
-		b.Truncate(0)
+		b.Reset()
 		return 0, 0, io.EOF
 	}
 	c := b.buf[b.off]
@@ -337,12 +373,12 @@
 
 // UnreadRune unreads the last rune returned by ReadRune.
 // If the most recent read or write operation on the buffer was
-// not a ReadRune, UnreadRune returns an error.  (In this regard
+// not a successful ReadRune, UnreadRune returns an error.  (In this regard
 // it is stricter than UnreadByte, which will unread the last byte
 // from any read operation.)
 func (b *Buffer) UnreadRune() error {
 	if b.lastRead <= opInvalid {
-		return errors.New("bytes.Buffer: UnreadRune: previous operation was not ReadRune")
+		return errors.New("bytes.Buffer: UnreadRune: previous operation was not a successful ReadRune")
 	}
 	if b.off >= int(b.lastRead) {
 		b.off -= int(b.lastRead)
@@ -351,12 +387,13 @@
 	return nil
 }
 
-// UnreadByte unreads the last byte returned by the most recent
-// read operation. If write has happened since the last read, UnreadByte
-// returns an error.
+// UnreadByte unreads the last byte returned by the most recent successful
+// read operation that read at least one byte. If a write has happened since
+// the last read, if the last read returned an error, or if the read read zero
+// bytes, UnreadByte returns an error.
 func (b *Buffer) UnreadByte() error {
 	if b.lastRead == opInvalid {
-		return errors.New("bytes.Buffer: UnreadByte: previous operation was not a read")
+		return errors.New("bytes.Buffer: UnreadByte: previous operation was not a successful read")
 	}
 	b.lastRead = opInvalid
 	if b.off > 0 {
@@ -404,10 +441,12 @@
 	return string(slice), err
 }
 
-// NewBuffer creates and initializes a new Buffer using buf as its initial
-// contents. It is intended to prepare a Buffer to read existing data. It
-// can also be used to size the internal buffer for writing. To do that,
-// buf should have the desired capacity but a length of zero.
+// NewBuffer creates and initializes a new Buffer using buf as its
+// initial contents. The new Buffer takes ownership of buf, and the
+// caller should not use buf after this call. NewBuffer is intended to
+// prepare a Buffer to read existing data. It can also be used to size
+// the internal buffer for writing. To do that, buf should have the
+// desired capacity but a length of zero.
 //
 // In most cases, new(Buffer) (or just declaring a Buffer variable) is
 // sufficient to initialize a Buffer.
diff --git a/libgo/go/bytes/buffer_test.go b/libgo/go/bytes/buffer_test.go
index b1b85f9..ce2f01a 100644
--- a/libgo/go/bytes/buffer_test.go
+++ b/libgo/go/bytes/buffer_test.go
@@ -6,8 +6,10 @@
 
 import (
 	. "bytes"
+	"internal/testenv"
 	"io"
 	"math/rand"
+	"os/exec"
 	"runtime"
 	"testing"
 	"unicode/utf8"
@@ -311,6 +313,19 @@
 
 	// Check that UnreadRune works
 	buf.Reset()
+
+	// check at EOF
+	if err := buf.UnreadRune(); err == nil {
+		t.Fatal("UnreadRune at EOF: got no error")
+	}
+	if _, _, err := buf.ReadRune(); err == nil {
+		t.Fatal("ReadRune at EOF: got no error")
+	}
+	if err := buf.UnreadRune(); err == nil {
+		t.Fatal("UnreadRune after ReadRune at EOF: got no error")
+	}
+
+	// check not at EOF
 	buf.Write(b)
 	for r := rune(0); r < NRune; r++ {
 		r1, size, _ := buf.ReadRune()
@@ -473,15 +488,34 @@
 
 func TestUnreadByte(t *testing.T) {
 	b := new(Buffer)
-	b.WriteString("abcdefghijklmnopqrstuvwxyz")
 
-	_, err := b.ReadBytes('m')
-	if err != nil {
-		t.Fatalf("ReadBytes: %v", err)
+	// check at EOF
+	if err := b.UnreadByte(); err == nil {
+		t.Fatal("UnreadByte at EOF: got no error")
+	}
+	if _, err := b.ReadByte(); err == nil {
+		t.Fatal("ReadByte at EOF: got no error")
+	}
+	if err := b.UnreadByte(); err == nil {
+		t.Fatal("UnreadByte after ReadByte at EOF: got no error")
 	}
 
-	err = b.UnreadByte()
-	if err != nil {
+	// check not at EOF
+	b.WriteString("abcdefghijklmnopqrstuvwxyz")
+
+	// after unsuccessful read
+	if n, err := b.Read(nil); n != 0 || err != nil {
+		t.Fatalf("Read(nil) = %d,%v; want 0,nil", n, err)
+	}
+	if err := b.UnreadByte(); err == nil {
+		t.Fatal("UnreadByte after Read(nil): got no error")
+	}
+
+	// after successful read
+	if _, err := b.ReadBytes('m'); err != nil {
+		t.Fatalf("ReadBytes: %v", err)
+	}
+	if err := b.UnreadByte(); err != nil {
 		t.Fatalf("UnreadByte: %v", err)
 	}
 	c, err := b.ReadByte()
@@ -514,6 +548,38 @@
 	}
 }
 
+// Test that tryGrowByReslice is inlined.
+// Only execute on "linux-amd64" builder in order to avoid breakage.
+func TestTryGrowByResliceInlined(t *testing.T) {
+	targetBuilder := "linux-amd64"
+	if testenv.Builder() != targetBuilder {
+		t.Skipf("%q gets executed on %q builder only", t.Name(), targetBuilder)
+	}
+	t.Parallel()
+	goBin := testenv.GoToolPath(t)
+	out, err := exec.Command(goBin, "tool", "nm", goBin).CombinedOutput()
+	if err != nil {
+		t.Fatalf("go tool nm: %v: %s", err, out)
+	}
+	// Verify this doesn't exist:
+	sym := "bytes.(*Buffer).tryGrowByReslice"
+	if Contains(out, []byte(sym)) {
+		t.Errorf("found symbol %q in cmd/go, but should be inlined", sym)
+	}
+}
+
+func BenchmarkWriteByte(b *testing.B) {
+	const n = 4 << 10
+	b.SetBytes(n)
+	buf := NewBuffer(make([]byte, n))
+	for i := 0; i < b.N; i++ {
+		buf.Reset()
+		for i := 0; i < n; i++ {
+			buf.WriteByte('x')
+		}
+	}
+}
+
 func BenchmarkWriteRune(b *testing.B) {
 	const n = 4 << 10
 	const r = '☺'
diff --git a/libgo/go/bytes/bytes.go b/libgo/go/bytes/bytes.go
index 406a382..7c878af 100644
--- a/libgo/go/bytes/bytes.go
+++ b/libgo/go/bytes/bytes.go
@@ -46,36 +46,21 @@
 	return a[0:na]
 }
 
-// Count counts the number of non-overlapping instances of sep in s.
-// If sep is an empty slice, Count returns 1 + the number of Unicode code points in s.
-func Count(s, sep []byte) int {
-	n := len(sep)
-	if n == 0 {
+// countGeneric actually implements Count
+func countGeneric(s, sep []byte) int {
+	// special case
+	if len(sep) == 0 {
 		return utf8.RuneCount(s) + 1
 	}
-	if n > len(s) {
-		return 0
-	}
-	count := 0
-	c := sep[0]
-	i := 0
-	t := s[:len(s)-n+1]
-	for i < len(t) {
-		if t[i] != c {
-			o := IndexByte(t[i:], c)
-			if o < 0 {
-				break
-			}
-			i += o
+	n := 0
+	for {
+		i := Index(s, sep)
+		if i == -1 {
+			return n
 		}
-		if n == 1 || Equal(s[i:i+n], sep) {
-			count++
-			i += n
-			continue
-		}
-		i++
+		n++
+		s = s[i+len(sep):]
 	}
-	return count
 }
 
 // Contains reports whether subslice is within b.
@@ -229,20 +214,21 @@
 	if n < 0 {
 		n = Count(s, sep) + 1
 	}
-	c := sep[0]
-	start := 0
+
 	a := make([][]byte, n)
-	na := 0
-	for i := 0; i+len(sep) <= len(s) && na+1 < n; i++ {
-		if s[i] == c && (len(sep) == 1 || Equal(s[i:i+len(sep)], sep)) {
-			a[na] = s[start : i+sepSave]
-			na++
-			start = i + len(sep)
-			i += len(sep) - 1
+	n--
+	i := 0
+	for i < n {
+		m := Index(s, sep)
+		if m < 0 {
+			break
 		}
+		a[i] = s[:m+sepSave]
+		s = s[m+len(sep):]
+		i++
 	}
-	a[na] = s[start:]
-	return a[0 : na+1]
+	a[i] = s
+	return a[:i+1]
 }
 
 // SplitN slices s into subslices separated by sep and returns a slice of
diff --git a/libgo/go/bytes/bytes_amd64.go b/libgo/go/bytes/bytes_amd64.go
index 58a07ef..d40c744 100644
--- a/libgo/go/bytes/bytes_amd64.go
+++ b/libgo/go/bytes/bytes_amd64.go
@@ -6,17 +6,19 @@
 
 package bytes
 
+import "internal/cpu"
+
 //go:noescape
 
 // indexShortStr returns the index of the first instance of c in s, or -1 if c is not present in s.
 // indexShortStr requires 2 <= len(c) <= shortStringLen
-func indexShortStr(s, c []byte) int // ../runtime/asm_$GOARCH.s
-func supportAVX2() bool             // ../runtime/asm_$GOARCH.s
+func indexShortStr(s, c []byte) int  // ../runtime/asm_amd64.s
+func countByte(s []byte, c byte) int // ../runtime/asm_amd64.s
 
 var shortStringLen int
 
 func init() {
-	if supportAVX2() {
+	if cpu.X86.HasAVX2 {
 		shortStringLen = 63
 	} else {
 		shortStringLen = 31
@@ -96,6 +98,15 @@
 	return -1
 }
 
+// Count counts the number of non-overlapping instances of sep in s.
+// If sep is an empty slice, Count returns 1 + the number of Unicode code points in s.
+func Count(s, sep []byte) int {
+	if len(sep) == 1 && cpu.X86.HasPOPCNT {
+		return countByte(s, sep[0])
+	}
+	return countGeneric(s, sep)
+}
+
 // primeRK is the prime base used in Rabin-Karp algorithm.
 const primeRK = 16777619
 
diff --git a/libgo/go/bytes/bytes_generic.go b/libgo/go/bytes/bytes_generic.go
index 91baa22..75a9c36 100644
--- a/libgo/go/bytes/bytes_generic.go
+++ b/libgo/go/bytes/bytes_generic.go
@@ -39,3 +39,9 @@
 	}
 	return -1
 }
+
+// Count counts the number of non-overlapping instances of sep in s.
+// If sep is an empty slice, Count returns 1 + the number of Unicode code points in s.
+func Count(s, sep []byte) int {
+	return countGeneric(s, sep)
+}
diff --git a/libgo/go/bytes/bytes_s390x.go b/libgo/go/bytes/bytes_s390x.go
index a05ca47..54e013e 100644
--- a/libgo/go/bytes/bytes_s390x.go
+++ b/libgo/go/bytes/bytes_s390x.go
@@ -99,6 +99,12 @@
 	return -1
 }
 
+// Count counts the number of non-overlapping instances of sep in s.
+// If sep is an empty slice, Count returns 1 + the number of Unicode code points in s.
+func Count(s, sep []byte) int {
+	return countGeneric(s, sep)
+}
+
 // primeRK is the prime base used in Rabin-Karp algorithm.
 const primeRK = 16777619
 
diff --git a/libgo/go/bytes/bytes_test.go b/libgo/go/bytes/bytes_test.go
index ad01952..d571eb3 100644
--- a/libgo/go/bytes/bytes_test.go
+++ b/libgo/go/bytes/bytes_test.go
@@ -401,6 +401,79 @@
 	}
 }
 
+// test count of a single byte across page offsets
+func TestCountByte(t *testing.T) {
+	b := make([]byte, 5015) // bigger than a page
+	windows := []int{1, 2, 3, 4, 15, 16, 17, 31, 32, 33, 63, 64, 65, 128}
+	testCountWindow := func(i, window int) {
+		for j := 0; j < window; j++ {
+			b[i+j] = byte(100)
+			p := Count(b[i:i+window], []byte{100})
+			if p != j+1 {
+				t.Errorf("TestCountByte.Count(%q, 100) = %d", b[i:i+window], p)
+			}
+			pGeneric := CountGeneric(b[i:i+window], []byte{100})
+			if pGeneric != j+1 {
+				t.Errorf("TestCountByte.CountGeneric(%q, 100) = %d", b[i:i+window], p)
+			}
+		}
+	}
+
+	maxWnd := windows[len(windows)-1]
+
+	for i := 0; i <= 2*maxWnd; i++ {
+		for _, window := range windows {
+			if window > len(b[i:]) {
+				window = len(b[i:])
+			}
+			testCountWindow(i, window)
+			for j := 0; j < window; j++ {
+				b[i+j] = byte(0)
+			}
+		}
+	}
+	for i := 4096 - (maxWnd + 1); i < len(b); i++ {
+		for _, window := range windows {
+			if window > len(b[i:]) {
+				window = len(b[i:])
+			}
+			testCountWindow(i, window)
+			for j := 0; j < window; j++ {
+				b[i+j] = byte(0)
+			}
+		}
+	}
+}
+
+// Make sure we don't count bytes outside our window
+func TestCountByteNoMatch(t *testing.T) {
+	b := make([]byte, 5015)
+	windows := []int{1, 2, 3, 4, 15, 16, 17, 31, 32, 33, 63, 64, 65, 128}
+	for i := 0; i <= len(b); i++ {
+		for _, window := range windows {
+			if window > len(b[i:]) {
+				window = len(b[i:])
+			}
+			// Fill the window with non-match
+			for j := 0; j < window; j++ {
+				b[i+j] = byte(100)
+			}
+			// Try to find something that doesn't exist
+			p := Count(b[i:i+window], []byte{0})
+			if p != 0 {
+				t.Errorf("TestCountByteNoMatch(%q, 0) = %d", b[i:i+window], p)
+			}
+			pGeneric := CountGeneric(b[i:i+window], []byte{0})
+			if pGeneric != 0 {
+				t.Errorf("TestCountByteNoMatch.CountGeneric(%q, 100) = %d", b[i:i+window], p)
+			}
+			for j := 0; j < window; j++ {
+				b[i+j] = byte(0)
+			}
+		}
+	}
+}
+
 var bmbuf []byte
 
 func valName(x int) string {
@@ -594,6 +667,26 @@
 	})
 }
 
+func BenchmarkCountSingle(b *testing.B) {
+	benchBytes(b, indexSizes, func(b *testing.B, n int) {
+		buf := bmbuf[0:n]
+		step := 8
+		for i := 0; i < len(buf); i += step {
+			buf[i] = 1
+		}
+		expect := (len(buf) + (step - 1)) / step
+		for i := 0; i < b.N; i++ {
+			j := Count(buf, []byte{1})
+			if j != expect {
+				b.Fatal("bad count", j, expect)
+			}
+		}
+		for i := 0; i < len(buf); i++ {
+			buf[i] = 0
+		}
+	})
+}
+
 type ExplodeTest struct {
 	s string
 	n int
@@ -1437,6 +1530,59 @@
 	}
 }
 
+func makeBenchInputHard() []byte {
+	tokens := [...]string{
+		"<a>", "<p>", "<b>", "<strong>",
+		"</a>", "</p>", "</b>", "</strong>",
+		"hello", "world",
+	}
+	x := make([]byte, 0, 1<<20)
+	for {
+		i := rand.Intn(len(tokens))
+		if len(x)+len(tokens[i]) >= 1<<20 {
+			break
+		}
+		x = append(x, tokens[i]...)
+	}
+	return x
+}
+
+var benchInputHard = makeBenchInputHard()
+
+func BenchmarkSplitEmptySeparator(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Split(benchInputHard, nil)
+	}
+}
+
+func BenchmarkSplitSingleByteSeparator(b *testing.B) {
+	sep := []byte("/")
+	for i := 0; i < b.N; i++ {
+		Split(benchInputHard, sep)
+	}
+}
+
+func BenchmarkSplitMultiByteSeparator(b *testing.B) {
+	sep := []byte("hello")
+	for i := 0; i < b.N; i++ {
+		Split(benchInputHard, sep)
+	}
+}
+
+func BenchmarkSplitNSingleByteSeparator(b *testing.B) {
+	sep := []byte("/")
+	for i := 0; i < b.N; i++ {
+		SplitN(benchInputHard, sep, 10)
+	}
+}
+
+func BenchmarkSplitNMultiByteSeparator(b *testing.B) {
+	sep := []byte("hello")
+	for i := 0; i < b.N; i++ {
+		SplitN(benchInputHard, sep, 10)
+	}
+}
+
 func BenchmarkRepeat(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		Repeat([]byte("-"), 80)
diff --git a/libgo/go/bytes/example_test.go b/libgo/go/bytes/example_test.go
index 0d35a0d..9397277 100644
--- a/libgo/go/bytes/example_test.go
+++ b/libgo/go/bytes/example_test.go
@@ -30,6 +30,15 @@
 	// Output: Gophers rule!
 }
 
+func ExampleBuffer_Grow() {
+	var b bytes.Buffer
+	b.Grow(64)
+	bb := b.Bytes()
+	b.Write([]byte("64 bytes or fewer"))
+	fmt.Printf("%q", bb[:b.Len()])
+	// Output: "64 bytes or fewer"
+}
+
 func ExampleCompare() {
 	// Interpret Compare's result by comparing it to zero.
 	var a, b []byte
diff --git a/libgo/go/bytes/export_test.go b/libgo/go/bytes/export_test.go
index f61523e..823c8b0 100644
--- a/libgo/go/bytes/export_test.go
+++ b/libgo/go/bytes/export_test.go
@@ -7,3 +7,4 @@
 // Export func for testing
 var IndexBytePortable = indexBytePortable
 var EqualPortable = equalPortable
+var CountGeneric = countGeneric
diff --git a/libgo/go/cmd/cgo/ast.go b/libgo/go/cmd/cgo/ast.go
index 8ce8241..7122a9d 100644
--- a/libgo/go/cmd/cgo/ast.go
+++ b/libgo/go/cmd/cgo/ast.go
@@ -17,8 +17,8 @@
 	"strings"
 )
 
-func parse(name string, flags parser.Mode) *ast.File {
-	ast1, err := parser.ParseFile(fset, name, nil, flags)
+func parse(name string, src []byte, flags parser.Mode) *ast.File {
+	ast1, err := parser.ParseFile(fset, name, src, flags)
 	if err != nil {
 		if list, ok := err.(scanner.ErrorList); ok {
 			// If err is a scanner.ErrorList, its String will print just
@@ -39,12 +39,12 @@
 	return fset.Position(n.Pos()).Line
 }
 
-// ReadGo populates f with information learned from reading the
-// Go source file with the given file name. It gathers the C preamble
+// ParseGo populates f with information learned from the Go source code
+// which was read from the named file. It gathers the C preamble
 // attached to the import "C" comment, a list of references to C.xxx,
 // a list of exported functions, and the actual AST, to be rewritten and
 // printed.
-func (f *File) ReadGo(name string) {
+func (f *File) ParseGo(name string, src []byte) {
 	// Create absolute path for file, so that it will be used in error
 	// messages and recorded in debug line number information.
 	// This matches the rest of the toolchain. See golang.org/issue/5122.
@@ -58,8 +58,8 @@
 	// so we use ast1 to look for the doc comments on import "C"
 	// and on exported functions, and we use ast2 for translating
 	// and reprinting.
-	ast1 := parse(name, parser.ParseComments)
-	ast2 := parse(name, 0)
+	ast1 := parse(name, src, parser.ParseComments)
+	ast2 := parse(name, src, 0)
 
 	f.Package = ast1.Name.Name
 	f.Name = make(map[string]*Name)
diff --git a/libgo/go/cmd/cgo/doc.go b/libgo/go/cmd/cgo/doc.go
index 85441e6..b238882 100644
--- a/libgo/go/cmd/cgo/doc.go
+++ b/libgo/go/cmd/cgo/doc.go
@@ -14,27 +14,27 @@
 
 If the import of "C" is immediately preceded by a comment, that
 comment, called the preamble, is used as a header when compiling
-the C parts of the package.  For example:
+the C parts of the package. For example:
 
 	// #include <stdio.h>
 	// #include <errno.h>
 	import "C"
 
 The preamble may contain any C code, including function and variable
-declarations and definitions.  These may then be referred to from Go
-code as though they were defined in the package "C".  All names
+declarations and definitions. These may then be referred to from Go
+code as though they were defined in the package "C". All names
 declared in the preamble may be used, even if they start with a
-lower-case letter.  Exception: static variables in the preamble may
+lower-case letter. Exception: static variables in the preamble may
 not be referenced from Go code; static functions are permitted.
 
-See $GOROOT/misc/cgo/stdio and $GOROOT/misc/cgo/gmp for examples.  See
+See $GOROOT/misc/cgo/stdio and $GOROOT/misc/cgo/gmp for examples. See
 "C? Go? Cgo!" for an introduction to using cgo:
 https://golang.org/doc/articles/c_go_cgo.html.
 
 CFLAGS, CPPFLAGS, CXXFLAGS, FFLAGS and LDFLAGS may be defined with pseudo
 #cgo directives within these comments to tweak the behavior of the C, C++
-or Fortran compiler.  Values defined in multiple directives are concatenated
-together.  The directive can include a list of build constraints limiting its
+or Fortran compiler. Values defined in multiple directives are concatenated
+together. The directive can include a list of build constraints limiting its
 effect to systems satisfying one of the constraints
 (see https://golang.org/pkg/go/build/#hdr-Build_Constraints for details about the constraint syntax).
 For example:
@@ -57,16 +57,16 @@
 
 When building, the CGO_CFLAGS, CGO_CPPFLAGS, CGO_CXXFLAGS, CGO_FFLAGS and
 CGO_LDFLAGS environment variables are added to the flags derived from
-these directives.  Package-specific flags should be set using the
+these directives. Package-specific flags should be set using the
 directives, not the environment variables, so that builds work in
 unmodified environments.
 
 All the cgo CPPFLAGS and CFLAGS directives in a package are concatenated and
-used to compile C files in that package.  All the CPPFLAGS and CXXFLAGS
+used to compile C files in that package. All the CPPFLAGS and CXXFLAGS
 directives in a package are concatenated and used to compile C++ files in that
-package.  All the CPPFLAGS and FFLAGS directives in a package are concatenated
-and used to compile Fortran files in that package.  All the LDFLAGS directives
-in any package in the program are concatenated and used at link time.  All the
+package. All the CPPFLAGS and FFLAGS directives in a package are concatenated
+and used to compile Fortran files in that package. All the LDFLAGS directives
+in any package in the program are concatenated and used at link time. All the
 pkg-config directives are concatenated and sent to pkg-config simultaneously
 to add to each appropriate set of command-line flags.
 
@@ -84,27 +84,27 @@
 
 When the Go tool sees that one or more Go files use the special import
 "C", it will look for other non-Go files in the directory and compile
-them as part of the Go package.  Any .c, .s, or .S files will be
-compiled with the C compiler.  Any .cc, .cpp, or .cxx files will be
-compiled with the C++ compiler.  Any .f, .F, .for or .f90 files will be
+them as part of the Go package. Any .c, .s, or .S files will be
+compiled with the C compiler. Any .cc, .cpp, or .cxx files will be
+compiled with the C++ compiler. Any .f, .F, .for or .f90 files will be
 compiled with the fortran compiler. Any .h, .hh, .hpp, or .hxx files will
 not be compiled separately, but, if these header files are changed,
-the C and C++ files will be recompiled.  The default C and C++
+the C and C++ files will be recompiled. The default C and C++
 compilers may be changed by the CC and CXX environment variables,
 respectively; those environment variables may include command line
 options.
 
 The cgo tool is enabled by default for native builds on systems where
-it is expected to work.  It is disabled by default when
-cross-compiling.  You can control this by setting the CGO_ENABLED
+it is expected to work. It is disabled by default when
+cross-compiling. You can control this by setting the CGO_ENABLED
 environment variable when running the go tool: set it to 1 to enable
-the use of cgo, and to 0 to disable it.  The go tool will set the
+the use of cgo, and to 0 to disable it. The go tool will set the
 build constraint "cgo" if cgo is enabled.
 
 When cross-compiling, you must specify a C cross-compiler for cgo to
-use.  You can do this by setting the CC_FOR_TARGET environment
+use. You can do this by setting the CC_FOR_TARGET environment
 variable when building the toolchain using make.bash, or by setting
-the CC environment variable any time you run the go tool.  The
+the CC environment variable any time you run the go tool. The
 CXX_FOR_TARGET and CXX environment variables work in a similar way for
 C++ code.
 
@@ -138,7 +138,7 @@
 Go structs cannot embed fields with C types.
 
 Go code cannot refer to zero-sized fields that occur at the end of
-non-empty C structs.  To get the address of such a field (which is the
+non-empty C structs. To get the address of such a field (which is the
 only operation you can do with a zero-sized field) you must take the
 address of the struct and add the size of the struct.
 
@@ -150,7 +150,7 @@
 Any C function (even void functions) may be called in a multiple
 assignment context to retrieve both the return value (if any) and the
 C errno variable as an error (use _ to skip the result value if the
-function returns void).  For example:
+function returns void). For example:
 
 	n, err = C.sqrt(-1)
 	_, err := C.voidFunc()
@@ -187,11 +187,11 @@
 In C, a function argument written as a fixed size array
 actually requires a pointer to the first element of the array.
 C compilers are aware of this calling convention and adjust
-the call accordingly, but Go cannot.  In Go, you must pass
+the call accordingly, but Go cannot. In Go, you must pass
 the pointer to the first element explicitly: C.f(&C.x[0]).
 
 A few special functions convert between Go and C types
-by making copies of the data.  In pseudo-Go definitions:
+by making copies of the data. In pseudo-Go definitions:
 
 	// Go string to C string
 	// The C string is allocated in the C heap using malloc.
@@ -253,50 +253,50 @@
 Passing pointers
 
 Go is a garbage collected language, and the garbage collector needs to
-know the location of every pointer to Go memory.  Because of this,
+know the location of every pointer to Go memory. Because of this,
 there are restrictions on passing pointers between Go and C.
 
 In this section the term Go pointer means a pointer to memory
 allocated by Go (such as by using the & operator or calling the
 predefined new function) and the term C pointer means a pointer to
-memory allocated by C (such as by a call to C.malloc).  Whether a
+memory allocated by C (such as by a call to C.malloc). Whether a
 pointer is a Go pointer or a C pointer is a dynamic property
 determined by how the memory was allocated; it has nothing to do with
 the type of the pointer.
 
 Go code may pass a Go pointer to C provided the Go memory to which it
-points does not contain any Go pointers.  The C code must preserve
+points does not contain any Go pointers. The C code must preserve
 this property: it must not store any Go pointers in Go memory, even
-temporarily.  When passing a pointer to a field in a struct, the Go
+temporarily. When passing a pointer to a field in a struct, the Go
 memory in question is the memory occupied by the field, not the entire
-struct.  When passing a pointer to an element in an array or slice,
+struct. When passing a pointer to an element in an array or slice,
 the Go memory in question is the entire array or the entire backing
 array of the slice.
 
 C code may not keep a copy of a Go pointer after the call returns.
 
-A Go function called by C code may not return a Go pointer.  A Go
+A Go function called by C code may not return a Go pointer. A Go
 function called by C code may take C pointers as arguments, and it may
 store non-pointer or C pointer data through those pointers, but it may
-not store a Go pointer in memory pointed to by a C pointer.  A Go
+not store a Go pointer in memory pointed to by a C pointer. A Go
 function called by C code may take a Go pointer as an argument, but it
 must preserve the property that the Go memory to which it points does
 not contain any Go pointers.
 
-Go code may not store a Go pointer in C memory.  C code may store Go
+Go code may not store a Go pointer in C memory. C code may store Go
 pointers in C memory, subject to the rule above: it must stop storing
 the Go pointer when the C function returns.
 
-These rules are checked dynamically at runtime.  The checking is
+These rules are checked dynamically at runtime. The checking is
 controlled by the cgocheck setting of the GODEBUG environment
-variable.  The default setting is GODEBUG=cgocheck=1, which implements
-reasonably cheap dynamic checks.  These checks may be disabled
-entirely using GODEBUG=cgocheck=0.  Complete checking of pointer
+variable. The default setting is GODEBUG=cgocheck=1, which implements
+reasonably cheap dynamic checks. These checks may be disabled
+entirely using GODEBUG=cgocheck=0. Complete checking of pointer
 handling, at some cost in run time, is available via GODEBUG=cgocheck=2.
 
 It is possible to defeat this enforcement by using the unsafe package,
 and of course there is nothing stopping the C code from doing anything
-it likes.  However, programs that break these rules are likely to fail
+it likes. However, programs that break these rules are likely to fail
 in unexpected and unpredictable ways.
 
 Using cgo directly
@@ -499,7 +499,7 @@
 	type _Ctype_void [0]byte
 
 The _cgo_gotypes.go file also contains the definitions of the
-functions.  They all have similar bodies that invoke runtime·cgocall
+functions. They all have similar bodies that invoke runtime·cgocall
 to make a switch from the Go runtime world to the system C (GCC-based)
 world.
 
@@ -835,7 +835,7 @@
 the host linker. The default value for the host linker is $CC, split
 into fields, or else "gcc". The specific host linker command line can
 be overridden using command line flags: cmd/link -extld=clang
--extldflags='-ggdb -O3'.  If any package in a build includes a .cc or
+-extldflags='-ggdb -O3'. If any package in a build includes a .cc or
 other file compiled by the C++ compiler, the go tool will use the
 -extld option to set the host linker to the C++ compiler.
 
diff --git a/libgo/go/cmd/cgo/gcc.go b/libgo/go/cmd/cgo/gcc.go
index 028804e..03239a0 100644
--- a/libgo/go/cmd/cgo/gcc.go
+++ b/libgo/go/cmd/cgo/gcc.go
@@ -20,6 +20,7 @@
 	"go/ast"
 	"go/parser"
 	"go/token"
+	"math"
 	"os"
 	"strconv"
 	"strings"
@@ -259,26 +260,26 @@
 		// If we've already found this name as a #define
 		// and we can translate it as a constant value, do so.
 		if n.Define != "" {
-			isConst := false
-			if _, err := strconv.Atoi(n.Define); err == nil {
-				isConst = true
-			} else if n.Define[0] == '"' || n.Define[0] == '\'' {
-				if _, err := parser.ParseExpr(n.Define); err == nil {
-					isConst = true
-				}
-			}
-			if isConst {
-				n.Kind = "const"
+			if i, err := strconv.ParseInt(n.Define, 0, 64); err == nil {
+				n.Kind = "iconst"
 				// Turn decimal into hex, just for consistency
 				// with enum-derived constants. Otherwise
 				// in the cgo -godefs output half the constants
 				// are in hex and half are in whatever the #define used.
-				i, err := strconv.ParseInt(n.Define, 0, 64)
-				if err == nil {
-					n.Const = fmt.Sprintf("%#x", i)
-				} else {
+				n.Const = fmt.Sprintf("%#x", i)
+			} else if n.Define[0] == '\'' {
+				if _, err := parser.ParseExpr(n.Define); err == nil {
+					n.Kind = "iconst"
 					n.Const = n.Define
 				}
+			} else if n.Define[0] == '"' {
+				if _, err := parser.ParseExpr(n.Define); err == nil {
+					n.Kind = "sconst"
+					n.Const = n.Define
+				}
+			}
+
+			if n.IsConst() {
 				continue
 			}
 
@@ -287,11 +288,10 @@
 			}
 		}
 
-		needType = append(needType, n)
-
 		// If this is a struct, union, or enum type name, no need to guess the kind.
 		if strings.HasPrefix(n.C, "struct ") || strings.HasPrefix(n.C, "union ") || strings.HasPrefix(n.C, "enum ") {
 			n.Kind = "type"
+			needType = append(needType, n)
 			continue
 		}
 
@@ -317,14 +317,24 @@
 	//	void __cgo_f_xxx_1(void) { __typeof__(name) *__cgo_undefined__; }
 	//	#line xxx "not-type"
 	//	void __cgo_f_xxx_2(void) { name *__cgo_undefined__; }
-	//	#line xxx "not-const"
+	//	#line xxx "not-int-const"
 	//	void __cgo_f_xxx_3(void) { enum { __cgo_undefined__ = (name)*1 }; }
+	//	#line xxx "not-num-const"
+	//	void __cgo_f_xxx_4(void) { static const double x = (name); }
+	//	#line xxx "not-str-lit"
+	//	void __cgo_f_xxx_5(void) { static const char x[] = (name); }
+	//	#line xxx "not-signed-int-const"
+	//	#if 0 < -(name)
+	//	#line xxx "not-signed-int-const"
+	//	#error found unsigned int
+	//	#endif
 	//
 	// If we see an error at not-declared:xxx, the corresponding name is not declared.
 	// If we see an error at not-type:xxx, the corresponding name is a type.
-	// If we see an error at not-const:xxx, the corresponding name is not an integer constant.
-	// If we see no errors, we assume the name is an expression but not a constant
-	// (so a variable or a function).
+	// If we see an error at not-int-const:xxx, the corresponding name is not an integer constant.
+	// If we see an error at not-num-const:xxx, the corresponding name is not a number constant.
+	// If we see an error at not-str-lit:xxx, the corresponding name is not a string literal.
+	// If we see an error at not-signed-int-const:xxx, the corresponding name is not a signed integer literal.
 	//
 	// The specific input forms are chosen so that they are valid C syntax regardless of
 	// whether name denotes a type or an expression.
@@ -338,11 +348,24 @@
 			"void __cgo_f_%d_1(void) { __typeof__(%s) *__cgo_undefined__; }\n"+
 			"#line %d \"not-type\"\n"+
 			"void __cgo_f_%d_2(void) { %s *__cgo_undefined__; }\n"+
-			"#line %d \"not-const\"\n"+
-			"void __cgo_f_%d_3(void) { enum { __cgo__undefined__ = (%s)*1 }; }\n",
+			"#line %d \"not-int-const\"\n"+
+			"void __cgo_f_%d_3(void) { enum { __cgo_undefined__ = (%s)*1 }; }\n"+
+			"#line %d \"not-num-const\"\n"+
+			"void __cgo_f_%d_4(void) { static const double x = (%s); }\n"+
+			"#line %d \"not-str-lit\"\n"+
+			"void __cgo_f_%d_5(void) { static const char s[] = (%s); }\n"+
+			"#line %d \"not-signed-int-const\"\n"+
+			"#if 0 < (%s)\n"+
+			"#line %d \"not-signed-int-const\"\n"+
+			"#error found unsigned int\n"+
+			"#endif\n",
 			i+1, i+1, n.C,
 			i+1, i+1, n.C,
-			i+1, i+1, n.C)
+			i+1, i+1, n.C,
+			i+1, i+1, n.C,
+			i+1, i+1, n.C,
+			i+1, n.C, i+1,
+		)
 	}
 	fmt.Fprintf(&b, "#line 1 \"completed\"\n"+
 		"int __cgo__1 = __cgo__2;\n")
@@ -356,13 +379,23 @@
 	sniff := make([]int, len(names))
 	const (
 		notType = 1 << iota
-		notConst
+		notIntConst
+		notNumConst
+		notStrLiteral
 		notDeclared
+		notSignedIntConst
 	)
+	sawUnmatchedErrors := false
 	for _, line := range strings.Split(stderr, "\n") {
-		if !strings.Contains(line, ": error:") {
-			// we only care about errors.
-			// we tried to turn off warnings on the command line, but one never knows.
+		// Ignore warnings and random comments, with one
+		// exception: newer GCC versions will sometimes emit
+		// an error on a macro #define with a note referring
+		// to where the expansion occurs. We care about where
+		// the expansion occurs, so in that case treat the note
+		// as an error.
+		isError := strings.Contains(line, ": error:")
+		isErrorNote := strings.Contains(line, ": note:") && sawUnmatchedErrors
+		if !isError && !isErrorNote {
 			continue
 		}
 
@@ -380,6 +413,9 @@
 		i, _ := strconv.Atoi(line[c1+1 : c2])
 		i--
 		if i < 0 || i >= len(names) {
+			if isError {
+				sawUnmatchedErrors = true
+			}
 			continue
 		}
 
@@ -395,9 +431,22 @@
 			sniff[i] |= notDeclared
 		case "not-type":
 			sniff[i] |= notType
-		case "not-const":
-			sniff[i] |= notConst
+		case "not-int-const":
+			sniff[i] |= notIntConst
+		case "not-num-const":
+			sniff[i] |= notNumConst
+		case "not-str-lit":
+			sniff[i] |= notStrLiteral
+		case "not-signed-int-const":
+			sniff[i] |= notSignedIntConst
+		default:
+			if isError {
+				sawUnmatchedErrors = true
+			}
+			continue
 		}
+
+		sawUnmatchedErrors = false
 	}
 
 	if !completed {
@@ -405,14 +454,29 @@
 	}
 
 	for i, n := range names {
-		switch sniff[i] {
+		switch sniff[i] &^ notSignedIntConst {
 		default:
-			error_(token.NoPos, "could not determine kind of name for C.%s", fixGo(n.Go))
-		case notType:
-			n.Kind = "const"
-		case notConst:
+			var tpos token.Pos
+			for _, ref := range f.Ref {
+				if ref.Name == n {
+					tpos = ref.Pos()
+					break
+				}
+			}
+			error_(tpos, "could not determine kind of name for C.%s", fixGo(n.Go))
+		case notStrLiteral | notType:
+			if sniff[i]&notSignedIntConst != 0 {
+				n.Kind = "uconst"
+			} else {
+				n.Kind = "iconst"
+			}
+		case notIntConst | notStrLiteral | notType:
+			n.Kind = "fconst"
+		case notIntConst | notNumConst | notType:
+			n.Kind = "sconst"
+		case notIntConst | notNumConst | notStrLiteral:
 			n.Kind = "type"
-		case notConst | notType:
+		case notIntConst | notNumConst | notStrLiteral | notType:
 			n.Kind = "not-type"
 		}
 	}
@@ -450,18 +514,16 @@
 	b.WriteString("#line 1 \"cgo-dwarf-inference\"\n")
 	for i, n := range names {
 		fmt.Fprintf(&b, "__typeof__(%s) *__cgo__%d;\n", n.C, i)
-		if n.Kind == "const" {
+		if n.Kind == "iconst" || n.Kind == "uconst" {
 			fmt.Fprintf(&b, "enum { __cgo_enum__%d = %s };\n", i, n.C)
 		}
 	}
 
-	// Apple's LLVM-based gcc does not include the enumeration
-	// names and values in its DWARF debug output. In case we're
-	// using such a gcc, create a data block initialized with the values.
-	// We can read them out of the object file.
-	fmt.Fprintf(&b, "long long __cgodebug_data[] = {\n")
+	// We create a data block initialized with the values,
+	// so we can read them out of the object file.
+	fmt.Fprintf(&b, "long long __cgodebug_ints[] = {\n")
 	for _, n := range names {
-		if n.Kind == "const" {
+		if n.Kind == "iconst" || n.Kind == "uconst" {
 			fmt.Fprintf(&b, "\t%s,\n", n.C)
 		} else {
 			fmt.Fprintf(&b, "\t0,\n")
@@ -475,15 +537,30 @@
 	fmt.Fprintf(&b, "\t1\n")
 	fmt.Fprintf(&b, "};\n")
 
-	d, bo, debugData := p.gccDebug(b.Bytes())
-	enumVal := make([]int64, len(debugData)/8)
-	for i := range enumVal {
-		enumVal[i] = int64(bo.Uint64(debugData[i*8:]))
+	// do the same work for floats.
+	fmt.Fprintf(&b, "double __cgodebug_floats[] = {\n")
+	for _, n := range names {
+		if n.Kind == "fconst" {
+			fmt.Fprintf(&b, "\t%s,\n", n.C)
+		} else {
+			fmt.Fprintf(&b, "\t0,\n")
+		}
 	}
+	fmt.Fprintf(&b, "\t1\n")
+	fmt.Fprintf(&b, "};\n")
+
+	// do the same work for strings.
+	for i, n := range names {
+		if n.Kind == "sconst" {
+			fmt.Fprintf(&b, "const char __cgodebug_str__%d[] = %s;\n", i, n.C)
+			fmt.Fprintf(&b, "const unsigned long long __cgodebug_strlen__%d = sizeof(%s)-1;\n", i, n.C)
+		}
+	}
+
+	d, ints, floats, strs := p.gccDebug(b.Bytes(), len(names))
 
 	// Scan DWARF info for top-level TagVariable entries with AttrName __cgo__i.
 	types := make([]dwarf.Type, len(names))
-	enums := make([]dwarf.Offset, len(names))
 	nameToIndex := make(map[*Name]int)
 	for i, n := range names {
 		nameToIndex[n] = i
@@ -502,26 +579,6 @@
 			break
 		}
 		switch e.Tag {
-		case dwarf.TagEnumerationType:
-			offset := e.Offset
-			for {
-				e, err := r.Next()
-				if err != nil {
-					fatalf("reading DWARF entry: %s", err)
-				}
-				if e.Tag == 0 {
-					break
-				}
-				if e.Tag == dwarf.TagEnumerator {
-					entryName := e.Val(dwarf.AttrName).(string)
-					if strings.HasPrefix(entryName, "__cgo_enum__") {
-						n, _ := strconv.Atoi(entryName[len("__cgo_enum__"):])
-						if 0 <= n && n < len(names) {
-							enums[n] = offset
-						}
-					}
-				}
-			}
 		case dwarf.TagVariable:
 			name, _ := e.Val(dwarf.AttrName).(string)
 			typOff, _ := e.Val(dwarf.AttrType).(dwarf.Offset)
@@ -548,15 +605,7 @@
 			if err != nil {
 				fatalf("malformed __cgo__ name: %s", name)
 			}
-			if enums[i] != 0 {
-				t, err := d.Type(enums[i])
-				if err != nil {
-					fatalf("loading DWARF type: %s", err)
-				}
-				types[i] = t
-			} else {
-				types[i] = t.Type
-			}
+			types[i] = t.Type
 		}
 		if e.Tag != dwarf.TagCompileUnit {
 			r.SkipChildren()
@@ -580,17 +629,23 @@
 			n.FuncType = conv.FuncType(f, pos)
 		} else {
 			n.Type = conv.Type(types[i], pos)
-			if enums[i] != 0 && n.Type.EnumValues != nil {
-				k := fmt.Sprintf("__cgo_enum__%d", i)
-				n.Kind = "const"
-				n.Const = fmt.Sprintf("%#x", n.Type.EnumValues[k])
-				// Remove injected enum to ensure the value will deep-compare
-				// equally in future loads of the same constant.
-				delete(n.Type.EnumValues, k)
-			}
-			// Prefer debug data over DWARF debug output, if we have it.
-			if n.Kind == "const" && i < len(enumVal) {
-				n.Const = fmt.Sprintf("%#x", enumVal[i])
+			switch n.Kind {
+			case "iconst":
+				if i < len(ints) {
+					n.Const = fmt.Sprintf("%#x", ints[i])
+				}
+			case "uconst":
+				if i < len(ints) {
+					n.Const = fmt.Sprintf("%#x", uint64(ints[i]))
+				}
+			case "fconst":
+				if i < len(floats) {
+					n.Const = fmt.Sprintf("%f", floats[i])
+				}
+			case "sconst":
+				if i < len(strs) {
+					n.Const = fmt.Sprintf("%q", strs[i])
+				}
 			}
 		}
 		conv.FinishType(pos)
@@ -1069,7 +1124,7 @@
 	// are trying to do a ,err call. Also check that
 	// functions are only used in calls.
 	for _, r := range f.Ref {
-		if r.Name.Kind == "const" && r.Name.Const == "" {
+		if r.Name.IsConst() && r.Name.Const == "" {
 			error_(r.Pos(), "unable to find value of constant C.%s", fixGo(r.Name.Go))
 		}
 		var expr ast.Expr = ast.NewIdent(r.Name.Mangle) // default
@@ -1109,6 +1164,10 @@
 			}
 		case "expr":
 			if r.Name.Kind == "func" {
+				if builtinDefs[r.Name.C] != "" {
+					error_(r.Pos(), "use of builtin '%s' not in function call", fixGo(r.Name.C))
+				}
+
 				// Function is being used in an expression, to e.g. pass around a C function pointer.
 				// Create a new Name for this Ref which causes the variable to be declared in Go land.
 				fpName := "fp_" + r.Name.Go
@@ -1277,12 +1336,55 @@
 
 // gccDebug runs gcc -gdwarf-2 over the C program stdin and
 // returns the corresponding DWARF data and, if present, debug data block.
-func (p *Package) gccDebug(stdin []byte) (*dwarf.Data, binary.ByteOrder, []byte) {
+func (p *Package) gccDebug(stdin []byte, nnames int) (d *dwarf.Data, ints []int64, floats []float64, strs []string) {
 	runGcc(stdin, p.gccCmd())
 
-	isDebugData := func(s string) bool {
+	isDebugInts := func(s string) bool {
 		// Some systems use leading _ to denote non-assembly symbols.
-		return s == "__cgodebug_data" || s == "___cgodebug_data"
+		return s == "__cgodebug_ints" || s == "___cgodebug_ints"
+	}
+	isDebugFloats := func(s string) bool {
+		// Some systems use leading _ to denote non-assembly symbols.
+		return s == "__cgodebug_floats" || s == "___cgodebug_floats"
+	}
+	indexOfDebugStr := func(s string) int {
+		// Some systems use leading _ to denote non-assembly symbols.
+		if strings.HasPrefix(s, "___") {
+			s = s[1:]
+		}
+		if strings.HasPrefix(s, "__cgodebug_str__") {
+			if n, err := strconv.Atoi(s[len("__cgodebug_str__"):]); err == nil {
+				return n
+			}
+		}
+		return -1
+	}
+	indexOfDebugStrlen := func(s string) int {
+		// Some systems use leading _ to denote non-assembly symbols.
+		if strings.HasPrefix(s, "___") {
+			s = s[1:]
+		}
+		if strings.HasPrefix(s, "__cgodebug_strlen__") {
+			if n, err := strconv.Atoi(s[len("__cgodebug_strlen__"):]); err == nil {
+				return n
+			}
+		}
+		return -1
+	}
+
+	strs = make([]string, nnames)
+
+	strdata := make(map[int]string, nnames)
+	strlens := make(map[int]int, nnames)
+
+	buildStrings := func() {
+		for n, strlen := range strlens {
+			data := strdata[n]
+			if len(data) <= strlen {
+				fatalf("invalid string literal")
+			}
+			strs[n] = string(data[:strlen])
+		}
 	}
 
 	if f, err := macho.Open(gccTmp()); err == nil {
@@ -1291,24 +1393,76 @@
 		if err != nil {
 			fatalf("cannot load DWARF output from %s: %v", gccTmp(), err)
 		}
-		var data []byte
+		bo := f.ByteOrder
 		if f.Symtab != nil {
 			for i := range f.Symtab.Syms {
 				s := &f.Symtab.Syms[i]
-				if isDebugData(s.Name) {
+				switch {
+				case isDebugInts(s.Name):
 					// Found it. Now find data section.
 					if i := int(s.Sect) - 1; 0 <= i && i < len(f.Sections) {
 						sect := f.Sections[i]
 						if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
 							if sdat, err := sect.Data(); err == nil {
-								data = sdat[s.Value-sect.Addr:]
+								data := sdat[s.Value-sect.Addr:]
+								ints = make([]int64, len(data)/8)
+								for i := range ints {
+									ints[i] = int64(bo.Uint64(data[i*8:]))
+								}
 							}
 						}
 					}
+				case isDebugFloats(s.Name):
+					// Found it. Now find data section.
+					if i := int(s.Sect) - 1; 0 <= i && i < len(f.Sections) {
+						sect := f.Sections[i]
+						if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
+							if sdat, err := sect.Data(); err == nil {
+								data := sdat[s.Value-sect.Addr:]
+								floats = make([]float64, len(data)/8)
+								for i := range floats {
+									floats[i] = math.Float64frombits(bo.Uint64(data[i*8:]))
+								}
+							}
+						}
+					}
+				default:
+					if n := indexOfDebugStr(s.Name); n != -1 {
+						// Found it. Now find data section.
+						if i := int(s.Sect) - 1; 0 <= i && i < len(f.Sections) {
+							sect := f.Sections[i]
+							if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
+								if sdat, err := sect.Data(); err == nil {
+									data := sdat[s.Value-sect.Addr:]
+									strdata[n] = string(data)
+								}
+							}
+						}
+						break
+					}
+					if n := indexOfDebugStrlen(s.Name); n != -1 {
+						// Found it. Now find data section.
+						if i := int(s.Sect) - 1; 0 <= i && i < len(f.Sections) {
+							sect := f.Sections[i]
+							if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
+								if sdat, err := sect.Data(); err == nil {
+									data := sdat[s.Value-sect.Addr:]
+									strlen := bo.Uint64(data[:8])
+									if strlen > (1<<(uint(p.IntSize*8)-1) - 1) { // greater than MaxInt?
+										fatalf("string literal too big")
+									}
+									strlens[n] = int(strlen)
+								}
+							}
+						}
+						break
+					}
 				}
 			}
+
+			buildStrings()
 		}
-		return d, f.ByteOrder, data
+		return d, ints, floats, strs
 	}
 
 	if f, err := elf.Open(gccTmp()); err == nil {
@@ -1317,25 +1471,77 @@
 		if err != nil {
 			fatalf("cannot load DWARF output from %s: %v", gccTmp(), err)
 		}
-		var data []byte
+		bo := f.ByteOrder
 		symtab, err := f.Symbols()
 		if err == nil {
 			for i := range symtab {
 				s := &symtab[i]
-				if isDebugData(s.Name) {
+				switch {
+				case isDebugInts(s.Name):
 					// Found it. Now find data section.
 					if i := int(s.Section); 0 <= i && i < len(f.Sections) {
 						sect := f.Sections[i]
 						if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
 							if sdat, err := sect.Data(); err == nil {
-								data = sdat[s.Value-sect.Addr:]
+								data := sdat[s.Value-sect.Addr:]
+								ints = make([]int64, len(data)/8)
+								for i := range ints {
+									ints[i] = int64(bo.Uint64(data[i*8:]))
+								}
 							}
 						}
 					}
+				case isDebugFloats(s.Name):
+					// Found it. Now find data section.
+					if i := int(s.Section); 0 <= i && i < len(f.Sections) {
+						sect := f.Sections[i]
+						if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
+							if sdat, err := sect.Data(); err == nil {
+								data := sdat[s.Value-sect.Addr:]
+								floats = make([]float64, len(data)/8)
+								for i := range floats {
+									floats[i] = math.Float64frombits(bo.Uint64(data[i*8:]))
+								}
+							}
+						}
+					}
+				default:
+					if n := indexOfDebugStr(s.Name); n != -1 {
+						// Found it. Now find data section.
+						if i := int(s.Section); 0 <= i && i < len(f.Sections) {
+							sect := f.Sections[i]
+							if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
+								if sdat, err := sect.Data(); err == nil {
+									data := sdat[s.Value-sect.Addr:]
+									strdata[n] = string(data)
+								}
+							}
+						}
+						break
+					}
+					if n := indexOfDebugStrlen(s.Name); n != -1 {
+						// Found it. Now find data section.
+						if i := int(s.Section); 0 <= i && i < len(f.Sections) {
+							sect := f.Sections[i]
+							if sect.Addr <= s.Value && s.Value < sect.Addr+sect.Size {
+								if sdat, err := sect.Data(); err == nil {
+									data := sdat[s.Value-sect.Addr:]
+									strlen := bo.Uint64(data[:8])
+									if strlen > (1<<(uint(p.IntSize*8)-1) - 1) { // greater than MaxInt?
+										fatalf("string literal too big")
+									}
+									strlens[n] = int(strlen)
+								}
+							}
+						}
+						break
+					}
 				}
 			}
+
+			buildStrings()
 		}
-		return d, f.ByteOrder, data
+		return d, ints, floats, strs
 	}
 
 	if f, err := pe.Open(gccTmp()); err == nil {
@@ -1344,20 +1550,70 @@
 		if err != nil {
 			fatalf("cannot load DWARF output from %s: %v", gccTmp(), err)
 		}
-		var data []byte
+		bo := binary.LittleEndian
 		for _, s := range f.Symbols {
-			if isDebugData(s.Name) {
+			switch {
+			case isDebugInts(s.Name):
 				if i := int(s.SectionNumber) - 1; 0 <= i && i < len(f.Sections) {
 					sect := f.Sections[i]
 					if s.Value < sect.Size {
 						if sdat, err := sect.Data(); err == nil {
-							data = sdat[s.Value:]
+							data := sdat[s.Value:]
+							ints = make([]int64, len(data)/8)
+							for i := range ints {
+								ints[i] = int64(bo.Uint64(data[i*8:]))
+							}
 						}
 					}
 				}
+			case isDebugFloats(s.Name):
+				if i := int(s.SectionNumber) - 1; 0 <= i && i < len(f.Sections) {
+					sect := f.Sections[i]
+					if s.Value < sect.Size {
+						if sdat, err := sect.Data(); err == nil {
+							data := sdat[s.Value:]
+							floats = make([]float64, len(data)/8)
+							for i := range floats {
+								floats[i] = math.Float64frombits(bo.Uint64(data[i*8:]))
+							}
+						}
+					}
+				}
+			default:
+				if n := indexOfDebugStr(s.Name); n != -1 {
+					if i := int(s.SectionNumber) - 1; 0 <= i && i < len(f.Sections) {
+						sect := f.Sections[i]
+						if s.Value < sect.Size {
+							if sdat, err := sect.Data(); err == nil {
+								data := sdat[s.Value:]
+								strdata[n] = string(data)
+							}
+						}
+					}
+					break
+				}
+				if n := indexOfDebugStrlen(s.Name); n != -1 {
+					if i := int(s.SectionNumber) - 1; 0 <= i && i < len(f.Sections) {
+						sect := f.Sections[i]
+						if s.Value < sect.Size {
+							if sdat, err := sect.Data(); err == nil {
+								data := sdat[s.Value:]
+								strlen := bo.Uint64(data[:8])
+								if strlen > (1<<(uint(p.IntSize*8)-1) - 1) { // greater than MaxInt?
+									fatalf("string literal too big")
+								}
+								strlens[n] = int(strlen)
+							}
+						}
+					}
+					break
+				}
 			}
 		}
-		return d, binary.LittleEndian, data
+
+		buildStrings()
+
+		return d, ints, floats, strs
 	}
 
 	fatalf("cannot parse gcc output %s as ELF, Mach-O, PE object", gccTmp())
@@ -2048,7 +2304,7 @@
 	}
 	var r *Type
 	var gr []*ast.Field
-	if _, ok := dtype.ReturnType.(*dwarf.VoidType); ok {
+	if _, ok := base(dtype.ReturnType).(*dwarf.VoidType); ok {
 		gr = []*ast.Field{{Type: c.goVoid}}
 	} else if dtype.ReturnType != nil {
 		r = c.Type(unqual(dtype.ReturnType), pos)
diff --git a/libgo/go/cmd/cgo/main.go b/libgo/go/cmd/cgo/main.go
index ac10205..c9a44fd 100644
--- a/libgo/go/cmd/cgo/main.go
+++ b/libgo/go/cmd/cgo/main.go
@@ -17,7 +17,7 @@
 	"go/ast"
 	"go/printer"
 	"go/token"
-	"io"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"reflect"
@@ -88,7 +88,7 @@
 	Mangle   string // name used in generated Go
 	C        string // name used in C
 	Define   string // #define expansion
-	Kind     string // "const", "type", "var", "fpvar", "func", "not-type"
+	Kind     string // "iconst", "uconst", "fconst", "sconst", "type", "var", "fpvar", "func", "not-type"
 	Type     *Type  // the type of xxx
 	FuncType *FuncType
 	AddError bool
@@ -100,6 +100,11 @@
 	return n.Kind == "var" || n.Kind == "fpvar"
 }
 
+// IsConst reports whether Kind is either "iconst", "uconst", "fconst" or "sconst"
+func (n *Name) IsConst() bool {
+	return strings.HasSuffix(n.Kind, "const")
+}
+
 // A ExpFunc is an exported function, callable from C.
 // Such functions are identified in the Go input file
 // by doc comments containing the line //export ExpName
@@ -274,30 +279,28 @@
 	// concern is other cgo wrappers for the same functions.
 	// Use the beginning of the md5 of the input to disambiguate.
 	h := md5.New()
-	for _, input := range goFiles {
-		if *srcDir != "" {
-			input = filepath.Join(*srcDir, input)
-		}
-		f, err := os.Open(input)
-		if err != nil {
-			fatalf("%s", err)
-		}
-		io.Copy(h, f)
-		f.Close()
-	}
-	cPrefix = fmt.Sprintf("_%x", h.Sum(nil)[0:6])
-
 	fs := make([]*File, len(goFiles))
 	for i, input := range goFiles {
 		if *srcDir != "" {
 			input = filepath.Join(*srcDir, input)
 		}
+
+		b, err := ioutil.ReadFile(input)
+		if err != nil {
+			fatalf("%s", err)
+		}
+		if _, err = h.Write(b); err != nil {
+			fatalf("%s", err)
+		}
+
 		f := new(File)
-		f.ReadGo(input)
+		f.ParseGo(input, b)
 		f.DiscardCgoDirectives()
 		fs[i] = f
 	}
 
+	cPrefix = fmt.Sprintf("_%x", h.Sum(nil)[0:6])
+
 	if *objDir == "" {
 		// make sure that _obj directory exists, so that we can write
 		// all the output files there.
diff --git a/libgo/go/cmd/cgo/out.go b/libgo/go/cmd/cgo/out.go
index a8292f2..c4ff07d 100644
--- a/libgo/go/cmd/cgo/out.go
+++ b/libgo/go/cmd/cgo/out.go
@@ -190,7 +190,7 @@
 	for _, key := range nameKeys(p.Name) {
 		n := p.Name[key]
 		if n.Const != "" {
-			fmt.Fprintf(fgo2, "const _Cconst_%s = %s\n", n.Go, n.Const)
+			fmt.Fprintf(fgo2, "const %s = %s\n", n.Mangle, n.Const)
 		}
 	}
 	fmt.Fprintf(fgo2, "\n")
@@ -1303,7 +1303,7 @@
 */
 #define __cgo_compile_assert_eq(x, y, name) typedef char name[(x-y)*(x-y)*-2+1];
 
-// Check at compile time that the sizes we use match our expectations.
+/* Check at compile time that the sizes we use match our expectations. */
 #define __cgo_size_assert(t, n) __cgo_compile_assert_eq(sizeof(t), n, _cgo_sizeof_##t##_is_not_##n)
 
 __cgo_size_assert(char, 1)
@@ -1328,6 +1328,27 @@
 `
 
 // This must match the TSAN code in runtime/cgo/libcgo.h.
+// This is used when the code is built with the C/C++ Thread SANitizer,
+// which is not the same as the Go race detector.
+// __tsan_acquire tells TSAN that we are acquiring a lock on a variable,
+// in this case _cgo_sync. __tsan_release releases the lock.
+// (There is no actual lock, we are just telling TSAN that there is.)
+//
+// When we call from Go to C we call _cgo_tsan_acquire.
+// When the C function returns we call _cgo_tsan_release.
+// Similarly, when C calls back into Go we call _cgo_tsan_release
+// and then call _cgo_tsan_acquire when we return to C.
+// These calls tell TSAN that there is a serialization point at the C call.
+//
+// This is necessary because TSAN, which is a C/C++ tool, can not see
+// the synchronization in the Go code. Without these calls, when
+// multiple goroutines call into C code, TSAN does not understand
+// that the calls are properly synchronized on the Go side.
+//
+// To be clear, if the calls are not properly synchronized on the Go side,
+// we will be hiding races. But when using TSAN on mixed Go C/C++ code
+// it is more important to avoid false positives, which reduce confidence
+// in the tool, than to avoid false negatives.
 const yesTsanProlog = `
 #line 1 "cgo-tsan-prolog"
 #define CGO_NO_SANITIZE_THREAD __attribute__ ((no_sanitize_thread))
diff --git a/libgo/go/cmd/go/alldocs.go b/libgo/go/cmd/go/alldocs.go
index f946bf6..6f9dc32 100644
--- a/libgo/go/cmd/go/alldocs.go
+++ b/libgo/go/cmd/go/alldocs.go
@@ -118,8 +118,8 @@
 // 		a suffix to use in the name of the package installation directory,
 // 		in order to keep output separate from default builds.
 // 		If using the -race flag, the install suffix is automatically set to race
-// 		or, if set explicitly, has _race appended to it.  Likewise for the -msan
-// 		flag.  Using a -buildmode option that requires non-default compile flags
+// 		or, if set explicitly, has _race appended to it. Likewise for the -msan
+// 		flag. Using a -buildmode option that requires non-default compile flags
 // 		has a similar effect.
 // 	-ldflags 'flag list'
 // 		arguments to pass on each go tool link invocation.
@@ -131,16 +131,17 @@
 // 		For example, when building with a non-standard configuration,
 // 		use -pkgdir to keep generated packages in a separate location.
 // 	-tags 'tag list'
-// 		a list of build tags to consider satisfied during the build.
-// 		For more information about build tags, see the description of
+// 		a space-separated list of build tags to consider satisfied during the
+// 		build. For more information about build tags, see the description of
 // 		build constraints in the documentation for the go/build package.
 // 	-toolexec 'cmd args'
 // 		a program to use to invoke toolchain programs like vet and asm.
 // 		For example, instead of running asm, the go command will run
 // 		'cmd args /path/to/asm <arguments for asm>'.
 //
-// The list flags accept a space-separated list of strings. To embed spaces
-// in an element in the list, surround it with either single or double quotes.
+// All the flags that take a list of arguments accept a space-separated
+// list of strings. To embed spaces in an element in the list, surround
+// it with either single or double quotes.
 //
 // For more about specifying packages, see 'go help packages'.
 // For more about where packages and binaries are installed,
@@ -208,12 +209,13 @@
 //
 // Usage:
 //
-// 	go doc [-u] [-c] [package|[package.]symbol[.method]]
+// 	go doc [-u] [-c] [package|[package.]symbol[.methodOrField]]
 //
 // Doc prints the documentation comments associated with the item identified by its
-// arguments (a package, const, func, type, var, or method) followed by a one-line
-// summary of each of the first-level items "under" that item (package-level
-// declarations for a package, methods for a type, etc.).
+// arguments (a package, const, func, type, var, method, or struct field)
+// followed by a one-line summary of each of the first-level items "under"
+// that item (package-level declarations for a package, methods for a type,
+// etc.).
 //
 // Doc accepts zero, one, or two arguments.
 //
@@ -231,9 +233,9 @@
 // which is schematically one of these:
 //
 // 	go doc <pkg>
-// 	go doc <sym>[.<method>]
-// 	go doc [<pkg>.]<sym>[.<method>]
-// 	go doc [<pkg>.][<sym>.]<method>
+// 	go doc <sym>[.<methodOrField>]
+// 	go doc [<pkg>.]<sym>[.<methodOrField>]
+// 	go doc [<pkg>.][<sym>.]<methodOrField>
 //
 // The first item in this list matched by the argument is the one whose documentation
 // is printed. (See the examples below.) However, if the argument starts with a capital
@@ -241,7 +243,7 @@
 //
 // For packages, the order of scanning is determined lexically in breadth-first order.
 // That is, the package presented is the one that matches the search and is nearest
-// the root and lexically first at its level of the hierarchy.  The GOROOT tree is
+// the root and lexically first at its level of the hierarchy. The GOROOT tree is
 // always scanned in its entirety before GOPATH.
 //
 // If there is no package specified or matched, the package in the current
@@ -253,10 +255,10 @@
 // elements like . and ... are not implemented by go doc.
 //
 // When run with two arguments, the first must be a full package path (not just a
-// suffix), and the second is a symbol or symbol and method; this is similar to the
-// syntax accepted by godoc:
+// suffix), and the second is a symbol, or symbol with method or struct field.
+// This is similar to the syntax accepted by godoc:
 //
-// 	go doc <pkg> <sym>[.<method>]
+// 	go doc <pkg> <sym>[.<methodOrField>]
 //
 // In all forms, when matching symbols, lower-case letters in the argument match
 // either case but upper-case letters match exactly. This means that there may be
@@ -307,22 +309,25 @@
 // 		when showing the package's top-level documentation.
 // 	-u
 // 		Show documentation for unexported as well as exported
-// 		symbols and methods.
+// 		symbols, methods, and fields.
 //
 //
 // Print Go environment information
 //
 // Usage:
 //
-// 	go env [var ...]
+// 	go env [-json] [var ...]
 //
 // Env prints Go environment information.
 //
 // By default env prints information as a shell script
-// (on Windows, a batch file).  If one or more variable
-// names is given as arguments,  env prints the value of
+// (on Windows, a batch file). If one or more variable
+// names is given as arguments, env prints the value of
 // each named variable on its own line.
 //
+// The -json flag prints the environment in JSON format
+// instead of as a shell script.
+//
 //
 // Start a bug report
 //
@@ -357,7 +362,7 @@
 // 	go fmt [-n] [-x] [packages]
 //
 // Fmt runs the command 'gofmt -l -w' on the packages named
-// by the import paths.  It prints the names of the files that are modified.
+// by the import paths. It prints the names of the files that are modified.
 //
 // For more about gofmt, see 'go doc cmd/gofmt'.
 // For more about specifying packages, see 'go help packages'.
@@ -427,7 +432,7 @@
 // As a last step before running the command, any invocations of any
 // environment variables with alphanumeric names, such as $GOFILE or
 // $HOME, are expanded throughout the command line. The syntax for
-// variable expansion is $NAME on all operating systems.  Due to the
+// variable expansion is $NAME on all operating systems. Due to the
 // order of evaluation, variables are expanded even inside quoted
 // strings. If the variable NAME is not set, $NAME expands to the
 // empty string.
@@ -504,7 +509,7 @@
 // the tests for the specified packages.
 //
 // The -u flag instructs get to use the network to update the named packages
-// and their dependencies.  By default, get uses the network to check out
+// and their dependencies. By default, get uses the network to check out
 // missing packages but does not use it to look for updates to existing packages.
 //
 // The -v flag enables verbose progress and debug output.
@@ -518,8 +523,8 @@
 // When checking out or updating a package, get looks for a branch or tag
 // that matches the locally installed version of Go. The most important
 // rule is that if the local installation is running version "go1", get
-// searches for a branch or tag named "go1". If no such version exists it
-// retrieves the most recent version of the package.
+// searches for a branch or tag named "go1". If no such version exists
+// it retrieves the default branch of the package.
 //
 // When go get checks out or updates a Git repository,
 // it also updates any git submodules referenced by the repository.
@@ -565,7 +570,7 @@
 //     golang.org/x/net/html
 //
 // The -f flag specifies an alternate format for the list, using the
-// syntax of package template.  The default output is equivalent to -f
+// syntax of package template. The default output is equivalent to -f
 // '{{.ImportPath}}'. The struct being passed to the template is:
 //
 //     type Package struct {
@@ -658,12 +663,12 @@
 // instead of using the template format.
 //
 // The -e flag changes the handling of erroneous packages, those that
-// cannot be found or are malformed.  By default, the list command
+// cannot be found or are malformed. By default, the list command
 // prints an error to standard error for each erroneous package and
 // omits the packages from consideration during the usual printing.
 // With the -e flag, the list command never prints errors to standard
 // error and instead processes the erroneous packages with the usual
-// printing.  Erroneous packages will have a non-empty ImportPath and
+// printing. Erroneous packages will have a non-empty ImportPath and
 // a non-nil Error field; other information may or may not be missing
 // (zeroed).
 //
@@ -716,7 +721,7 @@
 // the file pattern "*_test.go".
 // Files whose names begin with "_" (including "_test.go") or "." are ignored.
 // These additional files can contain test functions, benchmark functions, and
-// example functions.  See 'go help testfunc' for more.
+// example functions. See 'go help testfunc' for more.
 // Each listed package causes the execution of a separate test binary.
 //
 // Test files that declare a package with the suffix "_test" will be compiled as a
@@ -725,7 +730,7 @@
 // The go tool will ignore a directory named "testdata", making it available
 // to hold ancillary data needed by the tests.
 //
-// By default, go test needs no arguments.  It compiles and tests the package
+// By default, go test needs no arguments. It compiles and tests the package
 // with source in the current directory, including tests, and runs the tests.
 //
 // The package is built in a temporary directory so it does not interfere with the
@@ -793,15 +798,13 @@
 //
 // Usage:
 //
-// 	go vet [-n] [-x] [build flags] [packages]
+// 	go vet [-n] [-x] [build flags] [vet flags] [packages]
 //
 // Vet runs the Go vet command on the packages named by the import paths.
 //
-// For more about vet, see 'go doc cmd/vet'.
+// For more about vet and its flags, see 'go doc cmd/vet'.
 // For more about specifying packages, see 'go help packages'.
 //
-// To run the vet tool with specific options, run 'go tool vet'.
-//
 // The -n flag prints commands that would be executed.
 // The -x flag prints commands as they are executed.
 //
@@ -814,18 +817,18 @@
 //
 // There are two different ways to call between Go and C/C++ code.
 //
-// The first is the cgo tool, which is part of the Go distribution.  For
+// The first is the cgo tool, which is part of the Go distribution. For
 // information on how to use it see the cgo documentation (go doc cmd/cgo).
 //
 // The second is the SWIG program, which is a general tool for
-// interfacing between languages.  For information on SWIG see
-// http://swig.org/.  When running go build, any file with a .swig
-// extension will be passed to SWIG.  Any file with a .swigcxx extension
+// interfacing between languages. For information on SWIG see
+// http://swig.org/. When running go build, any file with a .swig
+// extension will be passed to SWIG. Any file with a .swigcxx extension
 // will be passed to SWIG with the -c++ option.
 //
 // When either cgo or SWIG is used, go build will pass any .c, .m, .s,
 // or .S files to the C compiler, and any .cc, .cpp, .cxx files to the C++
-// compiler.  The CC or CXX environment variables may be set to determine
+// compiler. The CC or CXX environment variables may be set to determine
 // the C or C++ compiler, respectively, to use.
 //
 //
@@ -846,10 +849,10 @@
 // 		exactly one main package to be listed.
 //
 // 	-buildmode=c-shared
-// 		Build the listed main packages, plus all packages that they
-// 		import, into C shared libraries. The only callable symbols will
+// 		Build the listed main package, plus all packages it imports,
+// 		into a C shared library. The only callable symbols will
 // 		be those functions exported using a cgo //export comment.
-// 		Non-main packages are ignored.
+// 		Requires exactly one main package to be listed.
 //
 // 	-buildmode=default
 // 		Listed main packages are built into executables and listed
@@ -938,7 +941,7 @@
 //
 // Each directory listed in GOPATH must have a prescribed structure:
 //
-// The src directory holds source code.  The path below src
+// The src directory holds source code. The path below src
 // determines the import path or executable name.
 //
 // The pkg directory holds installed package objects.
@@ -952,11 +955,11 @@
 //
 // The bin directory holds compiled commands.
 // Each command is named for its source directory, but only
-// the final element, not the entire path.  That is, the
+// the final element, not the entire path. That is, the
 // command with source in DIR/src/foo/quux is installed into
-// DIR/bin/quux, not DIR/bin/foo/quux.  The "foo/" prefix is stripped
+// DIR/bin/quux, not DIR/bin/foo/quux. The "foo/" prefix is stripped
 // so that you can add DIR/bin to your PATH to get at the
-// installed commands.  If the GOBIN environment variable is
+// installed commands. If the GOBIN environment variable is
 // set, commands are installed to the directory it names instead
 // of DIR/bin. GOBIN must be an absolute path.
 //
@@ -1099,7 +1102,7 @@
 // 	CC
 // 		The command to use to compile C code.
 // 	CGO_ENABLED
-// 		Whether the cgo command is supported.  Either 0 or 1.
+// 		Whether the cgo command is supported. Either 0 or 1.
 // 	CGO_CFLAGS
 // 		Flags that cgo will pass to the compiler when compiling
 // 		C code.
@@ -1151,7 +1154,7 @@
 // Import path syntax
 //
 // An import path (see 'go help packages') denotes a package stored in the local
-// file system.  In general, an import path denotes either a standard package (such
+// file system. In general, an import path denotes either a standard package (such
 // as "unicode/utf8") or a package found in one of the work spaces (For more
 // details see: 'go help gopath').
 //
@@ -1222,7 +1225,7 @@
 //
 // specifies the given repository, with or without the .vcs suffix,
 // using the named version control system, and then the path inside
-// that repository.  The supported version control systems are:
+// that repository. The supported version control systems are:
 //
 // 	Bazaar      .bzr
 // 	Git         .git
@@ -1242,7 +1245,7 @@
 // example.org/repo or repo.git.
 //
 // When a version control system supports multiple protocols,
-// each is tried in turn when downloading.  For example, a Git
+// each is tried in turn when downloading. For example, a Git
 // download tries https://, then git+ssh://.
 //
 // By default, downloads are restricted to known secure protocols
@@ -1360,17 +1363,28 @@
 //
 // An import path is a pattern if it includes one or more "..." wildcards,
 // each of which can match any string, including the empty string and
-// strings containing slashes.  Such a pattern expands to all package
+// strings containing slashes. Such a pattern expands to all package
 // directories found in the GOPATH trees with names matching the
-// patterns.  As a special case, x/... matches x as well as x's subdirectories.
-// For example, net/... expands to net and packages in its subdirectories.
+// patterns.
+//
+// To make common patterns more convenient, there are two special cases.
+// First, /... at the end of the pattern can match an empty string,
+// so that net/... matches both net and packages in its subdirectories, like net/http.
+// Second, any slash-separated pattern element containing a wildcard never
+// participates in a match of the "vendor" element in the path of a vendored
+// package, so that ./... does not match packages in subdirectories of
+// ./vendor or ./mycode/vendor, but ./vendor/... and ./mycode/vendor/... do.
+// Note, however, that a directory named vendor that itself contains code
+// is not a vendored package: cmd/vendor would be a command named vendor,
+// and the pattern cmd/... matches it.
+// See golang.org/s/go15vendor for more about vendoring.
 //
 // An import path can also name a package to be downloaded from
-// a remote repository.  Run 'go help importpath' for details.
+// a remote repository. Run 'go help importpath' for details.
 //
 // Every package in a program must have a unique import path.
 // By convention, this is arranged by starting each path with a
-// unique prefix that belongs to you.  For example, paths used
+// unique prefix that belongs to you. For example, paths used
 // internally at Google all begin with 'google', and paths
 // denoting remote repositories begin with the path to the code,
 // such as 'github.com/user/repo'.
@@ -1399,19 +1413,24 @@
 //
 // Several of the flags control profiling and write an execution profile
 // suitable for "go tool pprof"; run "go tool pprof -h" for more
-// information.  The --alloc_space, --alloc_objects, and --show_bytes
+// information. The --alloc_space, --alloc_objects, and --show_bytes
 // options of pprof control how the information is presented.
 //
 // The following flags are recognized by the 'go test' command and
 // control the execution of any test:
 //
 // 	-bench regexp
-// 	    Run (sub)benchmarks matching a regular expression.
-// 	    The given regular expression is split into smaller ones by
-// 	    top-level '/', where each must match the corresponding part of a
-// 	    benchmark's identifier.
-// 	    By default, no benchmarks run. To run all benchmarks,
-// 	    use '-bench .' or '-bench=.'.
+// 	    Run only those benchmarks matching a regular expression.
+// 	    By default, no benchmarks are run.
+// 	    To run all benchmarks, use '-bench .' or '-bench=.'.
+// 	    The regular expression is split by unbracketed slash (/)
+// 	    characters into a sequence of regular expressions, and each
+// 	    part of a benchmark's identifier must match the corresponding
+// 	    element in the sequence, if any. Possible parents of matches
+// 	    are run with b.N=1 to identify sub-benchmarks. For example,
+// 	    given -bench=X/Y, top-level benchmarks matching X are run
+// 	    with b.N=1 to find any sub-benchmarks matching Y, which are
+// 	    then run in full.
 //
 // 	-benchtime t
 // 	    Run enough iterations of each benchmark to take t, specified
@@ -1425,6 +1444,10 @@
 //
 // 	-cover
 // 	    Enable coverage analysis.
+// 	    Note that because coverage works by annotating the source
+// 	    code before compilation, compilation and test failures with
+// 	    coverage enabled may report line numbers that don't correspond
+// 	    to the original sources.
 //
 // 	-covermode set,count,atomic
 // 	    Set the mode for coverage analysis for the package[s]
@@ -1445,9 +1468,14 @@
 //
 // 	-cpu 1,2,4
 // 	    Specify a list of GOMAXPROCS values for which the tests or
-// 	    benchmarks should be executed.  The default is the current value
+// 	    benchmarks should be executed. The default is the current value
 // 	    of GOMAXPROCS.
 //
+// 	-list regexp
+// 	    List tests, benchmarks, or examples matching the regular expression.
+// 	    No tests, benchmarks or examples will be run. This will only
+// 	    list top-level tests. No subtest or subbenchmarks will be shown.
+//
 // 	-parallel n
 // 	    Allow parallel execution of test functions that call t.Parallel.
 // 	    The value of this flag is the maximum number of tests to run
@@ -1459,9 +1487,13 @@
 //
 // 	-run regexp
 // 	    Run only those tests and examples matching the regular expression.
-// 	    For tests the regular expression is split into smaller ones by
-// 	    top-level '/', where each must match the corresponding part of a
-// 	    test's identifier.
+// 	    For tests, the regular expression is split by unbracketed slash (/)
+// 	    characters into a sequence of regular expressions, and each part
+// 	    of a test's identifier must match the corresponding element in
+// 	    the sequence, if any. Note that possible parents of matches are
+// 	    run too, so that -run=X/Y matches and runs and reports the result
+// 	    of all tests matching X, even those without sub-tests matching Y,
+// 	    because it must run them to look for those sub-tests.
 //
 // 	-short
 // 	    Tell long-running tests to shorten their run time.
@@ -1469,8 +1501,8 @@
 // 	    the Go tree can run a sanity check but not spend time running
 // 	    exhaustive tests.
 //
-// 	-timeout t
-// 	    If a test runs longer than t, panic.
+// 	-timeout d
+// 	    If a test binary runs longer than duration d, panic.
 // 	    The default is 10 minutes (10m).
 //
 // 	-v
@@ -1493,7 +1525,7 @@
 // 	    calling runtime.SetBlockProfileRate with n.
 // 	    See 'go doc runtime.SetBlockProfileRate'.
 // 	    The profiler aims to sample, on average, one blocking event every
-// 	    n nanoseconds the program spends blocked.  By default,
+// 	    n nanoseconds the program spends blocked. By default,
 // 	    if -test.blockprofile is set without this flag, all blocking events
 // 	    are recorded, equivalent to -test.blockprofilerate=1.
 //
@@ -1511,7 +1543,7 @@
 //
 // 	-memprofilerate n
 // 	    Enable more precise (and expensive) memory profiles by setting
-// 	    runtime.MemProfileRate.  See 'go doc runtime.MemProfileRate'.
+// 	    runtime.MemProfileRate. See 'go doc runtime.MemProfileRate'.
 // 	    To profile all memory allocations, use -test.memprofilerate=1
 // 	    and pass --alloc_space flag to the pprof tool.
 //
@@ -1614,8 +1646,8 @@
 // "Output:" is compiled, executed, and expected to produce no output.
 //
 // Godoc displays the body of ExampleXXX to demonstrate the use
-// of the function, constant, or variable XXX.  An example of a method M with
-// receiver type T or *T is named ExampleT_M.  There may be multiple examples
+// of the function, constant, or variable XXX. An example of a method M with
+// receiver type T or *T is named ExampleT_M. There may be multiple examples
 // for a given function, constant, or variable, distinguished by a trailing _xxx,
 // where xxx is a suffix not beginning with an upper case letter.
 //
diff --git a/libgo/go/cmd/go/bootstrap.go b/libgo/go/cmd/go/bootstrap.go
deleted file mode 100644
index 2148d12..0000000
--- a/libgo/go/cmd/go/bootstrap.go
+++ /dev/null
@@ -1,41 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build cmd_go_bootstrap
-
-// This code is compiled only into the bootstrap 'go' binary.
-// These stubs avoid importing packages with large dependency
-// trees, like the use of "net/http" in vcs.go.
-
-package main
-
-import (
-	"errors"
-	"io"
-)
-
-var errHTTP = errors.New("no http in bootstrap go command")
-
-type httpError struct {
-	statusCode int
-}
-
-func (e *httpError) Error() string {
-	panic("unreachable")
-}
-
-func httpGET(url string) ([]byte, error) {
-	return nil, errHTTP
-}
-
-func httpsOrHTTP(importPath string, security securityMode) (string, io.ReadCloser, error) {
-	return "", nil, errHTTP
-}
-
-func parseMetaGoImports(r io.Reader) ([]metaImport, error) {
-	panic("unreachable")
-}
-
-func queryEscape(s string) string { panic("unreachable") }
-func openBrowser(url string) bool { panic("unreachable") }
diff --git a/libgo/go/cmd/go/build_test.go b/libgo/go/cmd/go/build_test.go
deleted file mode 100644
index 79bbd54..0000000
--- a/libgo/go/cmd/go/build_test.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
-	"os"
-	"reflect"
-	"testing"
-)
-
-func TestRemoveDevNull(t *testing.T) {
-	fi, err := os.Lstat(os.DevNull)
-	if err != nil {
-		t.Skip(err)
-	}
-	if fi.Mode().IsRegular() {
-		t.Errorf("Lstat(%s).Mode().IsRegular() = true; expected false", os.DevNull)
-	}
-	mayberemovefile(os.DevNull)
-	_, err = os.Lstat(os.DevNull)
-	if err != nil {
-		t.Errorf("mayberemovefile(%s) did remove it; oops", os.DevNull)
-	}
-}
-
-func TestSplitPkgConfigOutput(t *testing.T) {
-	for _, test := range []struct {
-		in   []byte
-		want []string
-	}{
-		{[]byte(`-r:foo -L/usr/white\ space/lib -lfoo\ bar -lbar\ baz`), []string{"-r:foo", "-L/usr/white space/lib", "-lfoo bar", "-lbar baz"}},
-		{[]byte(`-lextra\ fun\ arg\\`), []string{`-lextra fun arg\`}},
-		{[]byte(`broken flag\`), []string{"broken", "flag"}},
-		{[]byte("\textra     whitespace\r\n"), []string{"extra", "whitespace"}},
-		{[]byte("     \r\n      "), nil},
-	} {
-		got := splitPkgConfigOutput(test.in)
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("splitPkgConfigOutput(%v) = %v; want %v", test.in, got, test.want)
-		}
-	}
-}
diff --git a/libgo/go/cmd/go/env.go b/libgo/go/cmd/go/env.go
deleted file mode 100644
index 31710b7..0000000
--- a/libgo/go/cmd/go/env.go
+++ /dev/null
@@ -1,138 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
-	"fmt"
-	"os"
-	"runtime"
-	"strings"
-)
-
-var cmdEnv = &Command{
-	Run:       runEnv,
-	UsageLine: "env [var ...]",
-	Short:     "print Go environment information",
-	Long: `
-Env prints Go environment information.
-
-By default env prints information as a shell script
-(on Windows, a batch file).  If one or more variable
-names is given as arguments,  env prints the value of
-each named variable on its own line.
-	`,
-}
-
-type envVar struct {
-	name, value string
-}
-
-func mkEnv() []envVar {
-	var b builder
-	b.init()
-
-	env := []envVar{
-		{"GOARCH", goarch},
-		{"GOBIN", gobin},
-		{"GOEXE", exeSuffix},
-		{"GOHOSTARCH", runtime.GOARCH},
-		{"GOHOSTOS", runtime.GOOS},
-		{"GOOS", goos},
-		{"GOPATH", buildContext.GOPATH},
-		{"GORACE", os.Getenv("GORACE")},
-		{"GOROOT", goroot},
-		{"GOTOOLDIR", toolDir},
-
-		// disable escape codes in clang errors
-		{"TERM", "dumb"},
-	}
-
-	if gccgoBin != "" {
-		env = append(env, envVar{"GCCGO", gccgoBin})
-	} else {
-		env = append(env, envVar{"GCCGO", gccgoName})
-	}
-
-	switch goarch {
-	case "arm":
-		env = append(env, envVar{"GOARM", os.Getenv("GOARM")})
-	case "386":
-		env = append(env, envVar{"GO386", os.Getenv("GO386")})
-	}
-
-	cmd := b.gccCmd(".")
-	env = append(env, envVar{"CC", cmd[0]})
-	env = append(env, envVar{"GOGCCFLAGS", strings.Join(cmd[3:], " ")})
-	cmd = b.gxxCmd(".")
-	env = append(env, envVar{"CXX", cmd[0]})
-
-	if buildContext.CgoEnabled {
-		env = append(env, envVar{"CGO_ENABLED", "1"})
-	} else {
-		env = append(env, envVar{"CGO_ENABLED", "0"})
-	}
-
-	return env
-}
-
-func findEnv(env []envVar, name string) string {
-	for _, e := range env {
-		if e.name == name {
-			return e.value
-		}
-	}
-	return ""
-}
-
-// extraEnvVars returns environment variables that should not leak into child processes.
-func extraEnvVars() []envVar {
-	var b builder
-	b.init()
-	cppflags, cflags, cxxflags, fflags, ldflags := b.cflags(&Package{})
-	return []envVar{
-		{"PKG_CONFIG", b.pkgconfigCmd()},
-		{"CGO_CFLAGS", strings.Join(cflags, " ")},
-		{"CGO_CPPFLAGS", strings.Join(cppflags, " ")},
-		{"CGO_CXXFLAGS", strings.Join(cxxflags, " ")},
-		{"CGO_FFLAGS", strings.Join(fflags, " ")},
-		{"CGO_LDFLAGS", strings.Join(ldflags, " ")},
-	}
-}
-
-func runEnv(cmd *Command, args []string) {
-	env := newEnv
-	env = append(env, extraEnvVars()...)
-	if len(args) > 0 {
-		for _, name := range args {
-			fmt.Printf("%s\n", findEnv(env, name))
-		}
-		return
-	}
-
-	for _, e := range env {
-		if e.name != "TERM" {
-			switch runtime.GOOS {
-			default:
-				fmt.Printf("%s=\"%s\"\n", e.name, e.value)
-			case "plan9":
-				if strings.IndexByte(e.value, '\x00') < 0 {
-					fmt.Printf("%s='%s'\n", e.name, strings.Replace(e.value, "'", "''", -1))
-				} else {
-					v := strings.Split(e.value, "\x00")
-					fmt.Printf("%s=(", e.name)
-					for x, s := range v {
-						if x > 0 {
-							fmt.Printf(" ")
-						}
-						fmt.Printf("%s", s)
-					}
-					fmt.Printf(")\n")
-				}
-			case "windows":
-				fmt.Printf("set %s=%s\n", e.name, e.value)
-			}
-		}
-	}
-}
diff --git a/libgo/go/cmd/go/go_test.go b/libgo/go/cmd/go/go_test.go
index eaa8685..28fb5ef 100644
--- a/libgo/go/cmd/go/go_test.go
+++ b/libgo/go/cmd/go/go_test.go
@@ -7,7 +7,6 @@
 import (
 	"bytes"
 	"fmt"
-	"go/build"
 	"go/format"
 	"internal/race"
 	"internal/testenv"
@@ -74,6 +73,13 @@
 	}
 }
 
+// testGOROOT is the GOROOT to use when running testgo, a cmd/go binary
+// build from this process's current GOROOT, but run from a different
+// (temp) directory.
+var testGOROOT string
+
+var testCC string
+
 // The TestMain function creates a go command for testing purposes and
 // deletes it after the tests have been run.
 func TestMain(m *testing.M) {
@@ -88,6 +94,20 @@
 			os.Exit(2)
 		}
 
+		out, err = exec.Command("go", "env", "GOROOT").CombinedOutput()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "could not find testing GOROOT: %v\n%s", err, out)
+			os.Exit(2)
+		}
+		testGOROOT = strings.TrimSpace(string(out))
+
+		out, err = exec.Command("go", "env", "CC").CombinedOutput()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "could not find testing CC: %v\n%s", err, out)
+			os.Exit(2)
+		}
+		testCC = strings.TrimSpace(string(out))
+
 		if out, err := exec.Command("./testgo"+exeSuffix, "env", "CGO_ENABLED").Output(); err != nil {
 			fmt.Fprintf(os.Stderr, "running testgo failed: %v\n", err)
 			canRun = false
@@ -100,7 +120,9 @@
 
 		switch runtime.GOOS {
 		case "linux", "darwin", "freebsd", "windows":
-			canRace = canCgo && runtime.GOARCH == "amd64" && runtime.Compiler != "gccgo"
+			// The race detector doesn't work on Alpine Linux:
+			// golang.org/issue/14481
+			canRace = canCgo && runtime.GOARCH == "amd64" && !isAlpineLinux() && runtime.Compiler != "gccgo"
 		}
 	}
 
@@ -111,7 +133,7 @@
 	if home, ccacheDir := os.Getenv("HOME"), os.Getenv("CCACHE_DIR"); home != "" && ccacheDir == "" {
 		// On some systems the default C compiler is ccache.
 		// Setting HOME to a non-existent directory will break
-		// those systems.  Set CCACHE_DIR to cope.  Issue 17668.
+		// those systems. Set CCACHE_DIR to cope. Issue 17668.
 		os.Setenv("CCACHE_DIR", filepath.Join(home, ".ccache"))
 	}
 	os.Setenv("HOME", "/test-go-home-does-not-exist")
@@ -125,6 +147,14 @@
 	os.Exit(r)
 }
 
+func isAlpineLinux() bool {
+	if runtime.GOOS != "linux" {
+		return false
+	}
+	fi, err := os.Lstat("/etc/alpine-release")
+	return err == nil && fi.Mode().IsRegular()
+}
+
 // The length of an mtime tick on this system. This is an estimate of
 // how long we need to sleep to ensure that the mtime of two files is
 // different.
@@ -251,6 +281,13 @@
 	}
 }
 
+func (tg *testgoData) goTool() string {
+	if tg.wd == "" {
+		return "./testgo" + exeSuffix
+	}
+	return filepath.Join(tg.wd, "testgo"+exeSuffix)
+}
+
 // doRun runs the test go command, recording stdout and stderr and
 // returning exit status.
 func (tg *testgoData) doRun(args []string) error {
@@ -264,13 +301,20 @@
 			}
 		}
 	}
-	tg.t.Logf("running testgo %v", args)
-	var prog string
-	if tg.wd == "" {
-		prog = "./testgo" + exeSuffix
-	} else {
-		prog = filepath.Join(tg.wd, "testgo"+exeSuffix)
+
+	hasGoroot := false
+	for _, v := range tg.env {
+		if strings.HasPrefix(v, "GOROOT=") {
+			hasGoroot = true
+			break
+		}
 	}
+	prog := tg.goTool()
+	if !hasGoroot {
+		tg.setenv("GOROOT", testGOROOT)
+	}
+
+	tg.t.Logf("running testgo %v", args)
 	cmd := exec.Command(prog, args...)
 	tg.stdout.Reset()
 	tg.stderr.Reset()
@@ -365,7 +409,7 @@
 
 // doGrep looks for a regular expression in a buffer and fails if it
 // is not found. The name argument is the name of the output we are
-// searching, "output" or "error".  The msg argument is logged on
+// searching, "output" or "error". The msg argument is logged on
 // failure.
 func (tg *testgoData) doGrep(match string, b *bytes.Buffer, name, msg string) {
 	if !tg.doGrepMatch(match, b) {
@@ -1354,7 +1398,7 @@
 	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
 	tg.setenv("CGO_ENABLED", "0")
 	tg.runFail("install", "cgotest")
-	tg.grepStderr("no buildable Go source files", "go install cgotest did not report 'no buildable Go Source files'")
+	tg.grepStderr("build constraints exclude all Go files", "go install cgotest did not report 'build constraints exclude all Go files'")
 }
 
 func TestRelativeGOBINFail(t *testing.T) {
@@ -1483,11 +1527,11 @@
 	tg.setenv("GOPATH", tg.path("."))
 	tg.setenv("GOBIN", tg.path("gobin"))
 	tg.runFail("get", "-d", "golang.org/x/tools")
-	tg.grepStderr("golang.org/x/tools: no buildable Go source files", "missing error")
+	tg.grepStderr("golang.org/x/tools: no Go files", "missing error")
 	tg.runFail("get", "-d", "-u", "golang.org/x/tools")
-	tg.grepStderr("golang.org/x/tools: no buildable Go source files", "missing error")
+	tg.grepStderr("golang.org/x/tools: no Go files", "missing error")
 	tg.runFail("get", "-d", "golang.org/x/tools")
-	tg.grepStderr("golang.org/x/tools: no buildable Go source files", "missing error")
+	tg.grepStderr("golang.org/x/tools: no Go files", "missing error")
 }
 
 func TestGoGetTestOnlyPkg(t *testing.T) {
@@ -1753,7 +1797,7 @@
 	tg.grepStderr(regexp.QuoteMeta(tg.path("home/go/src/github.com/golang/example/hello"))+`.*from \$GOPATH`, "expected default GOPATH")
 }
 
-// Issue 4186.  go get cannot be used to download packages to $GOROOT.
+// Issue 4186. go get cannot be used to download packages to $GOROOT.
 // Test that without GOPATH set, go get should fail.
 func TestGoGetIntoGOROOT(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
@@ -1895,10 +1939,7 @@
 
 // Issue 4568.
 func TestSymlinksList(t *testing.T) {
-	switch runtime.GOOS {
-	case "plan9", "windows":
-		t.Skipf("skipping symlink test on %s", runtime.GOOS)
-	}
+	testenv.MustHaveSymlink(t)
 
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -1916,10 +1957,7 @@
 
 // Issue 14054.
 func TestSymlinksVendor(t *testing.T) {
-	switch runtime.GOOS {
-	case "plan9", "windows":
-		t.Skipf("skipping symlink test on %s", runtime.GOOS)
-	}
+	testenv.MustHaveSymlink(t)
 
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -1943,10 +1981,7 @@
 
 // Issue 15201.
 func TestSymlinksVendor15201(t *testing.T) {
-	switch runtime.GOOS {
-	case "plan9", "windows":
-		t.Skipf("skipping symlink test on %s", runtime.GOOS)
-	}
+	testenv.MustHaveSymlink(t)
 
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -1963,10 +1998,7 @@
 }
 
 func TestSymlinksInternal(t *testing.T) {
-	switch runtime.GOOS {
-	case "plan9", "windows":
-		t.Skipf("skipping symlink test on %s", runtime.GOOS)
-	}
+	testenv.MustHaveSymlink(t)
 
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -2030,8 +2062,10 @@
 		)`)
 	tg.tempFile("src/example/a/pkg/pkg.go", `package pkg`)
 	tg.tempFile("src/example/a/Pkg/pkg.go", `package pkg`)
-	tg.runFail("list", "example/a")
-	tg.grepStderr("case-insensitive import collision", "go list example/a did not report import collision")
+	tg.run("list", "-json", "example/a")
+	tg.grepStdout("case-insensitive import collision", "go list -json example/a did not report import collision")
+	tg.runFail("build", "example/a")
+	tg.grepStderr("case-insensitive import collision", "go build example/a did not report import collision")
 	tg.tempFile("src/example/b/file.go", `package b`)
 	tg.tempFile("src/example/b/FILE.go", `package b`)
 	f, err := os.Open(tg.path("src/example/b"))
@@ -2049,6 +2083,38 @@
 	}
 	tg.runFail(args...)
 	tg.grepStderr("case-insensitive file name collision", "go list example/b did not report file name collision")
+
+	tg.runFail("list", "example/a/pkg", "example/a/Pkg")
+	tg.grepStderr("case-insensitive import collision", "go list example/a/pkg example/a/Pkg did not report import collision")
+	tg.run("list", "-json", "-e", "example/a/pkg", "example/a/Pkg")
+	tg.grepStdout("case-insensitive import collision", "go list -json -e example/a/pkg example/a/Pkg did not report import collision")
+	tg.runFail("build", "example/a/pkg", "example/a/Pkg")
+	tg.grepStderr("case-insensitive import collision", "go build example/a/pkg example/a/Pkg did not report import collision")
+}
+
+// Issue 17451, 17662.
+func TestSymlinkWarning(t *testing.T) {
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.parallel()
+	tg.makeTempdir()
+	tg.setenv("GOPATH", tg.path("."))
+
+	tg.tempDir("src/example/xx")
+	tg.tempDir("yy/zz")
+	tg.tempFile("yy/zz/zz.go", "package zz\n")
+	if err := os.Symlink(tg.path("yy"), tg.path("src/example/xx/yy")); err != nil {
+		t.Skip("symlink failed: %v", err)
+	}
+	tg.run("list", "example/xx/z...")
+	tg.grepStdoutNot(".", "list should not have matched anything")
+	tg.grepStderr("matched no packages", "list should have reported that pattern matched no packages")
+	tg.grepStderrNot("symlink", "list should not have reported symlink")
+
+	tg.run("list", "example/xx/...")
+	tg.grepStdoutNot(".", "list should not have matched anything")
+	tg.grepStderr("matched no packages", "list should have reported that pattern matched no packages")
+	tg.grepStderr("ignoring symlink", "list should have reported symlink")
 }
 
 // Issue 8181.
@@ -2195,29 +2261,6 @@
 	checkCoverage(tg, data)
 }
 
-func TestCoverageUsesActualSettingToOverrideEvenForRace(t *testing.T) {
-	if testing.Short() {
-		t.Skip("don't build libraries for coverage in short mode")
-	}
-	if !canRace {
-		t.Skip("skipping because race detector not supported")
-	}
-
-	tg := testgo(t)
-	defer tg.cleanup()
-	tg.creatingTemp("testdata/cover.out")
-	tg.run("test", "-short", "-race", "-cover", "encoding/binary", "-covermode=count", "-coverprofile=testdata/cover.out")
-	data := tg.getStdout() + tg.getStderr()
-	if out, err := ioutil.ReadFile("testdata/cover.out"); err != nil {
-		t.Error(err)
-	} else {
-		if !bytes.Contains(out, []byte("mode: count")) {
-			t.Error("missing mode: count")
-		}
-	}
-	checkCoverage(tg, data)
-}
-
 func TestCoverageImportMainLoop(t *testing.T) {
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -2228,6 +2271,20 @@
 	tg.grepStderr("not an importable package", "did not detect import main")
 }
 
+func TestPluginNonMain(t *testing.T) {
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	pkg := filepath.Join(wd, "testdata", "testdep", "p2")
+
+	tg := testgo(t)
+	defer tg.cleanup()
+
+	tg.runFail("build", "-buildmode=plugin", pkg)
+}
+
 func TestTestEmpty(t *testing.T) {
 	if !canRace {
 		t.Skip("no race detector")
@@ -2235,7 +2292,6 @@
 
 	wd, _ := os.Getwd()
 	testdata := filepath.Join(wd, "testdata")
-
 	for _, dir := range []string{"pkg", "test", "xtest", "pkgtest", "pkgxtest", "pkgtestxtest", "testxtest"} {
 		t.Run(dir, func(t *testing.T) {
 			tg := testgo(t)
@@ -2250,10 +2306,36 @@
 	}
 }
 
+func TestNoGoError(t *testing.T) {
+	wd, _ := os.Getwd()
+	testdata := filepath.Join(wd, "testdata")
+	for _, dir := range []string{"empty/test", "empty/xtest", "empty/testxtest", "exclude", "exclude/ignore", "exclude/empty"} {
+		t.Run(dir, func(t *testing.T) {
+			tg := testgo(t)
+			defer tg.cleanup()
+			tg.setenv("GOPATH", testdata)
+			tg.cd(filepath.Join(testdata, "src"))
+			tg.runFail("build", "./"+dir)
+			var want string
+			if strings.Contains(dir, "test") {
+				want = "no non-test Go files in "
+			} else if dir == "exclude" {
+				want = "build constraints exclude all Go files in "
+			} else {
+				want = "no Go files in "
+			}
+			tg.grepStderr(want, "wrong reason for failure")
+		})
+	}
+}
+
 func TestTestRaceInstall(t *testing.T) {
 	if !canRace {
 		t.Skip("no race detector")
 	}
+	if testing.Short() && testenv.Builder() == "" {
+		t.Skip("don't rebuild the standard library in short mode")
+	}
 
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -2308,6 +2390,19 @@
 	}
 }
 
+func TestCgoAsmError(t *testing.T) {
+	if !canCgo {
+		t.Skip("skipping because cgo not enabled")
+	}
+
+	tg := testgo(t)
+	tg.parallel()
+	defer tg.cleanup()
+	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
+	tg.runFail("build", "cgoasm")
+	tg.grepBoth("package using cgo has Go assembly file", "did not detect Go assembly file")
+}
+
 func TestCgoDependsOnSyscall(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping test that removes $GOROOT/pkg/*_race in short mode")
@@ -2445,7 +2540,7 @@
 func main() { C.f() }`)
 	tg.setenv("GOPATH", tg.path("."))
 	tg.run("build", "-n", "-compiler", "gccgo", "cgoref")
-	tg.grepStderr(`gccgo.*\-L alibpath \-lalib`, `no Go-inline "#cgo LDFLAGS:" ("-L alibpath -lalib") passed to gccgo linking stage`)
+	tg.grepStderr(`gccgo.*\-L [^ ]*alibpath \-lalib`, `no Go-inline "#cgo LDFLAGS:" ("-L alibpath -lalib") passed to gccgo linking stage`)
 }
 
 func TestListTemplateContextFunction(t *testing.T) {
@@ -2535,7 +2630,7 @@
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.runFail("build", "./testdata/testonly")
-	tg.grepStderr("no buildable Go", "go build ./testdata/testonly produced unexpected error")
+	tg.grepStderr("no non-test Go files in", "go build ./testdata/testonly produced unexpected error")
 }
 
 func TestGoTestDetectsTestOnlyImportCycles(t *testing.T) {
@@ -2674,8 +2769,7 @@
 }
 
 func TestGoVetWithExternalTests(t *testing.T) {
-	testenv.MustHaveExternalNetwork(t)
-
+	skipIfGccgo(t, "gccgo does not have vet")
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.makeTempdir()
@@ -2686,19 +2780,39 @@
 }
 
 func TestGoVetWithTags(t *testing.T) {
-	testenv.MustHaveExternalNetwork(t)
-
+	skipIfGccgo(t, "gccgo does not have vet")
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.makeTempdir()
 	tg.run("install", "cmd/vet")
 	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
 	tg.runFail("vet", "-tags", "tagtest", "vetpkg")
-	tg.grepBoth(`c\.go.*wrong number of args for format`, "go get vetpkg did not run scan tagged file")
+	tg.grepBoth(`c\.go.*wrong number of args for format`, "go vet vetpkg did not run scan tagged file")
 }
 
-// Issue 9767.
-func TestGoGetRscIoToolstash(t *testing.T) {
+func TestGoVetWithFlagsOn(t *testing.T) {
+	skipIfGccgo(t, "gccgo does not have vet")
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.makeTempdir()
+	tg.run("install", "cmd/vet")
+	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
+	tg.runFail("vet", "-printf", "vetpkg")
+	tg.grepBoth("missing argument for Printf", "go vet -printf vetpkg did not find missing argument for Printf")
+}
+
+func TestGoVetWithFlagsOff(t *testing.T) {
+	skipIfGccgo(t, "gccgo does not have vet")
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.makeTempdir()
+	tg.run("install", "cmd/vet")
+	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
+	tg.run("vet", "-printf=false", "vetpkg")
+}
+
+// Issue 9767, 19769.
+func TestGoGetDotSlashDownload(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 
 	tg := testgo(t)
@@ -2706,7 +2820,7 @@
 	tg.tempDir("src/rsc.io")
 	tg.setenv("GOPATH", tg.path("."))
 	tg.cd(tg.path("src/rsc.io"))
-	tg.run("get", "./toolstash")
+	tg.run("get", "./pprof_mac_fix")
 }
 
 // Issue 13037: Was not parsing <meta> tags in 404 served over HTTPS
@@ -3047,17 +3161,8 @@
 }
 
 func TestGoTestRaceInstallCgo(t *testing.T) {
-	skipIfGccgo(t, "gccgo has no race detector")
-
-	switch sys := runtime.GOOS + "/" + runtime.GOARCH; sys {
-	case "darwin/amd64", "freebsd/amd64", "linux/amd64", "windows/amd64":
-		// ok
-	default:
-		t.Skip("no race detector on %s", sys)
-	}
-
-	if !build.Default.CgoEnabled {
-		t.Skip("no race detector without cgo")
+	if !canRace {
+		t.Skip("skipping because race detector not supported")
 	}
 
 	// golang.org/issue/10500.
@@ -3071,7 +3176,7 @@
 	tg.run("test", "-race", "-i", "runtime/race")
 	new, err := os.Stat(cgo)
 	tg.must(err)
-	if new.ModTime() != old.ModTime() {
+	if !new.ModTime().Equal(old.ModTime()) {
 		t.Fatalf("go test -i runtime/race reinstalled cmd/cgo")
 	}
 }
@@ -3100,7 +3205,7 @@
 func TestGoTestImportErrorStack(t *testing.T) {
 	const out = `package testdep/p1 (test)
 	imports testdep/p2
-	imports testdep/p3: no buildable Go source files`
+	imports testdep/p3: build constraints exclude all Go files `
 
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -3141,6 +3246,20 @@
 	tg.run("get", "-d", "-u", "github.com/rsc/go-get-issue-9224-cmd")
 }
 
+// Issue #20512.
+func TestGoGetRace(t *testing.T) {
+	testenv.MustHaveExternalNetwork(t)
+	if !canRace {
+		t.Skip("skipping because race detector not supported")
+	}
+
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.makeTempdir()
+	tg.setenv("GOPATH", tg.path("."))
+	tg.run("get", "-race", "github.com/rsc/go-get-issue-9224-cmd")
+}
+
 func TestGoGetDomainRoot(t *testing.T) {
 	// golang.org/issue/9357.
 	// go get foo.io (not foo.io/subdir) was not working consistently.
@@ -3477,7 +3596,7 @@
 		func F() { p1.F(true) }
 	`)
 	tg.runFail("install", "p2")
-	tg.grepStderr("no buildable Go source files", "did not complain about missing sources")
+	tg.grepStderr("no Go files", "did not complain about missing sources")
 
 	tg.tempFile("src/p1/missing.go", `//go:binary-only-package
 
@@ -3675,6 +3794,28 @@
 	tg.grepBoth(okPattern, "go test did not say ok")
 }
 
+func TestBenchmarkLabels(t *testing.T) {
+	tg := testgo(t)
+	defer tg.cleanup()
+	// TODO: tg.parallel()
+	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
+	tg.run("test", "-run", "^$", "-bench", ".", "bench")
+	tg.grepStdout(`(?m)^goos: `+runtime.GOOS, "go test did not print goos")
+	tg.grepStdout(`(?m)^goarch: `+runtime.GOARCH, "go test did not print goarch")
+	tg.grepStdout(`(?m)^pkg: bench`, "go test did not say pkg: bench")
+	tg.grepBothNot(`(?s)pkg:.*pkg:`, "go test said pkg multiple times")
+}
+
+func TestBenchmarkLabelsOutsideGOPATH(t *testing.T) {
+	tg := testgo(t)
+	defer tg.cleanup()
+	// TODO: tg.parallel()
+	tg.run("test", "-run", "^$", "-bench", ".", "testdata/standalone_benchmark_test.go")
+	tg.grepStdout(`(?m)^goos: `+runtime.GOOS, "go test did not print goos")
+	tg.grepStdout(`(?m)^goarch: `+runtime.GOARCH, "go test did not print goarch")
+	tg.grepBothNot(`(?m)^pkg:`, "go test did say pkg:")
+}
+
 func TestMatchesOnlyTestIsOK(t *testing.T) {
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -3804,3 +3945,431 @@
 	tg.grepStdout("pkgs$", "expected package not listed")
 	tg.grepStdout("pkgs/a", "expected package not listed")
 }
+
+// Issue 18975.
+func TestFFLAGS(t *testing.T) {
+	if !canCgo {
+		t.Skip("skipping because cgo not enabled")
+	}
+
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.parallel()
+
+	tg.tempFile("p/src/p/main.go", `package main
+		// #cgo FFLAGS: -no-such-fortran-flag
+		import "C"
+		func main() {}
+	`)
+	tg.tempFile("p/src/p/a.f", `! comment`)
+	tg.setenv("GOPATH", tg.path("p"))
+
+	// This should normally fail because we are passing an unknown flag,
+	// but issue #19080 points to Fortran compilers that succeed anyhow.
+	// To work either way we call doRun directly rather than run or runFail.
+	tg.doRun([]string{"build", "-x", "p"})
+
+	tg.grepStderr("no-such-fortran-flag", `missing expected "-no-such-fortran-flag"`)
+}
+
+// Issue 19198.
+// This is really a cmd/link issue but this is a convenient place to test it.
+func TestDuplicateGlobalAsmSymbols(t *testing.T) {
+	skipIfGccgo(t, "gccgo does not use cmd/asm")
+	if runtime.GOARCH != "386" && runtime.GOARCH != "amd64" {
+		t.Skipf("skipping test on %s", runtime.GOARCH)
+	}
+	if !canCgo {
+		t.Skip("skipping because cgo not enabled")
+	}
+
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.parallel()
+
+	asm := `
+#include "textflag.h"
+
+DATA sym<>+0x0(SB)/8,$0
+GLOBL sym<>(SB),(NOPTR+RODATA),$8
+
+TEXT ·Data(SB),NOSPLIT,$0
+	MOVB sym<>(SB), AX
+	MOVB AX, ret+0(FP)
+	RET
+`
+	tg.tempFile("go/src/a/a.s", asm)
+	tg.tempFile("go/src/a/a.go", `package a; func Data() uint8`)
+	tg.tempFile("go/src/b/b.s", asm)
+	tg.tempFile("go/src/b/b.go", `package b; func Data() uint8`)
+	tg.tempFile("go/src/p/p.go", `
+package main
+import "a"
+import "b"
+import "C"
+func main() {
+	_ = a.Data() + b.Data()
+}
+`)
+	tg.setenv("GOPATH", tg.path("go"))
+	exe := filepath.Join(tg.tempdir, "p.exe")
+	tg.creatingTemp(exe)
+	tg.run("build", "-o", exe, "p")
+}
+
+func TestBuildTagsNoComma(t *testing.T) {
+	skipIfGccgo(t, "gccgo has no standard packages")
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.makeTempdir()
+	tg.setenv("GOPATH", tg.path("go"))
+	tg.run("install", "-tags", "tag1 tag2", "math")
+	tg.runFail("install", "-tags", "tag1,tag2", "math")
+	tg.grepBoth("space-separated list contains comma", "-tags with a comma-separated list didn't error")
+	tg.runFail("build", "-tags", "tag1,tag2", "math")
+	tg.grepBoth("space-separated list contains comma", "-tags with a comma-separated list didn't error")
+}
+
+func copyFile(src, dst string, perm os.FileMode) error {
+	sf, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer sf.Close()
+
+	df, err := os.OpenFile(dst, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+
+	_, err = io.Copy(df, sf)
+	err2 := df.Close()
+	if err != nil {
+		return err
+	}
+	return err2
+}
+
+func TestExecutableGOROOT(t *testing.T) {
+	skipIfGccgo(t, "gccgo has no GOROOT")
+	if runtime.GOOS == "openbsd" {
+		t.Skipf("test case does not work on %s, missing os.Executable", runtime.GOOS)
+	}
+
+	// Env with no GOROOT.
+	var env []string
+	for _, e := range os.Environ() {
+		if !strings.HasPrefix(e, "GOROOT=") {
+			env = append(env, e)
+		}
+	}
+
+	check := func(t *testing.T, exe, want string) {
+		cmd := exec.Command(exe, "env", "GOROOT")
+		cmd.Env = env
+		out, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Fatalf("%s env GOROOT: %v, %s", exe, err, out)
+		}
+		goroot, err := filepath.EvalSymlinks(strings.TrimSpace(string(out)))
+		if err != nil {
+			t.Fatal(err)
+		}
+		want, err = filepath.EvalSymlinks(want)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !strings.EqualFold(goroot, want) {
+			t.Errorf("go env GOROOT:\nhave %s\nwant %s", goroot, want)
+		} else {
+			t.Logf("go env GOROOT: %s", goroot)
+		}
+	}
+
+	// Note: Must not call tg methods inside subtests: tg is attached to outer t.
+	tg := testgo(t)
+	defer tg.cleanup()
+
+	tg.makeTempdir()
+	tg.tempDir("new/bin")
+	newGoTool := tg.path("new/bin/go" + exeSuffix)
+	tg.must(copyFile(tg.goTool(), newGoTool, 0775))
+	newRoot := tg.path("new")
+
+	t.Run("RelocatedExe", func(t *testing.T) {
+		t.Skip("TODO: skipping known broken test; see golang.org/issue/20284")
+
+		// Should fall back to default location in binary.
+		// No way to dig out other than look at source code.
+		data, err := ioutil.ReadFile("../../runtime/internal/sys/zversion.go")
+		if err != nil {
+			t.Fatal(err)
+		}
+		m := regexp.MustCompile("const DefaultGoroot = `([^`]+)`").FindStringSubmatch(string(data))
+		if m == nil {
+			t.Fatal("cannot find DefaultGoroot in ../../runtime/internal/sys/zversion.go")
+		}
+		check(t, newGoTool, m[1])
+	})
+
+	// If the binary is sitting in a bin dir next to ../pkg/tool, that counts as a GOROOT,
+	// so it should find the new tree.
+	tg.tempDir("new/pkg/tool")
+	t.Run("RelocatedTree", func(t *testing.T) {
+		check(t, newGoTool, newRoot)
+	})
+
+	tg.tempDir("other/bin")
+	symGoTool := tg.path("other/bin/go" + exeSuffix)
+
+	// Symlink into go tree should still find go tree.
+	t.Run("SymlinkedExe", func(t *testing.T) {
+		testenv.MustHaveSymlink(t)
+		if err := os.Symlink(newGoTool, symGoTool); err != nil {
+			t.Fatal(err)
+		}
+		check(t, symGoTool, newRoot)
+	})
+}
+
+func TestNeedVersion(t *testing.T) {
+	skipIfGccgo(t, "gccgo does not use cmd/compile")
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.parallel()
+	tg.tempFile("goversion.go", `package main; func main() {}`)
+	path := tg.path("goversion.go")
+	tg.setenv("TESTGO_VERSION", "go1.testgo")
+	tg.runFail("run", path)
+	tg.grepStderr("compile", "does not match go tool version")
+}
+
+// Test that user can override default code generation flags.
+func TestUserOverrideFlags(t *testing.T) {
+	skipIfGccgo(t, "gccgo does not use -gcflags")
+	if !canCgo {
+		t.Skip("skipping because cgo not enabled")
+	}
+	if runtime.GOOS != "linux" {
+		// We are testing platform-independent code, so it's
+		// OK to skip cases that work differently.
+		t.Skipf("skipping on %s because test only works if c-archive implies -shared", runtime.GOOS)
+	}
+
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.parallel()
+	tg.tempFile("override.go", `package main
+
+import "C"
+
+//export GoFunc
+func GoFunc() {}
+
+func main() {}`)
+	tg.creatingTemp("override.a")
+	tg.creatingTemp("override.h")
+	tg.run("build", "-x", "-buildmode=c-archive", "-gcflags=-shared=false", tg.path("override.go"))
+	tg.grepStderr("compile .*-shared .*-shared=false", "user can not override code generation flag")
+}
+
+func TestCgoFlagContainsSpace(t *testing.T) {
+	if !canCgo {
+		t.Skip("skipping because cgo not enabled")
+	}
+
+	tg := testgo(t)
+	defer tg.cleanup()
+
+	ccName := filepath.Base(testCC)
+
+	tg.tempFile(fmt.Sprintf("src/%s/main.go", ccName), fmt.Sprintf(`package main
+		import (
+			"os"
+			"os/exec"
+			"path/filepath"
+			"strings"
+		)
+
+		func main() {
+			cmd := exec.Command(%q, os.Args[1:]...)
+			cmd.Stdin = os.Stdin
+			cmd.Stdout = os.Stdout
+			cmd.Stderr = os.Stderr
+			err := cmd.Run()
+			if err != nil {
+				panic(err)
+			}
+
+			if os.Args[len(os.Args)-1] == "trivial.c" {
+				return
+			}
+			if filepath.Base(os.Args[len(os.Args)-1]) == "_cgo_defun.c" {
+				return
+			}
+
+			var success bool
+			for _, arg := range os.Args {
+				switch {
+				case strings.Contains(arg, "c flags"):
+					if success {
+						panic("duplicate CFLAGS")
+					}
+					success = true
+				case strings.Contains(arg, "ld flags"):
+					if success {
+						panic("duplicate LDFLAGS")
+					}
+					success = true
+				}
+			}
+			if !success {
+				panic("args should contains '-Ic flags' or '-Lld flags'")
+			}
+		}
+	`, testCC))
+	tg.cd(tg.path(fmt.Sprintf("src/%s", ccName)))
+	tg.run("build")
+	tg.setenv("CC", tg.path(fmt.Sprintf("src/%s/%s", ccName, ccName)))
+
+	tg.tempFile("src/cgo/main.go", `package main
+		// #cgo CFLAGS: -I"c flags"
+		// #cgo LDFLAGS: -L"ld flags"
+		import "C"
+		func main() {}
+	`)
+	tg.cd(tg.path("src/cgo"))
+	tg.run("run", "main.go")
+}
+
+// Issue #20435.
+func TestGoTestRaceCoverModeFailures(t *testing.T) {
+	if !canRace {
+		t.Skip("skipping because race detector not supported")
+	}
+
+	tg := testgo(t)
+	tg.parallel()
+	defer tg.cleanup()
+	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
+
+	tg.run("test", "testrace")
+
+	tg.runFail("test", "-race", "-covermode=set", "testrace")
+	tg.grepStderr(`-covermode must be "atomic", not "set", when -race is enabled`, "-race -covermode=set was allowed")
+	tg.grepBothNot("PASS", "something passed")
+}
+
+// Issue 9737: verify that GOARM and GO386 affect the computed build ID.
+func TestBuildIDContainsArchModeEnv(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping in short mode")
+	}
+
+	var tg *testgoData
+	testWith := func(before, after func()) func(*testing.T) {
+		return func(t *testing.T) {
+			tg = testgo(t)
+			defer tg.cleanup()
+			tg.tempFile("src/mycmd/x.go", `package main
+func main() {}`)
+			tg.setenv("GOPATH", tg.path("."))
+
+			tg.cd(tg.path("src/mycmd"))
+			tg.setenv("GOOS", "linux")
+			before()
+			tg.run("install", "mycmd")
+			after()
+			tg.wantStale("mycmd", "build ID mismatch", "should be stale after environment variable change")
+		}
+	}
+
+	t.Run("386", testWith(func() {
+		tg.setenv("GOARCH", "386")
+		tg.setenv("GO386", "387")
+	}, func() {
+		tg.setenv("GO386", "sse2")
+	}))
+
+	t.Run("arm", testWith(func() {
+		tg.setenv("GOARCH", "arm")
+		tg.setenv("GOARM", "5")
+	}, func() {
+		tg.setenv("GOARM", "7")
+	}))
+}
+
+func TestTestRegexps(t *testing.T) {
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
+	tg.run("test", "-cpu=1", "-run=X/Y", "-bench=X/Y", "-count=2", "-v", "testregexp")
+	var lines []string
+	for _, line := range strings.SplitAfter(tg.getStdout(), "\n") {
+		if strings.Contains(line, "=== RUN") || strings.Contains(line, "--- BENCH") || strings.Contains(line, "LOG") {
+			lines = append(lines, line)
+		}
+	}
+
+	// Important parts:
+	//	TestX is run, twice
+	//	TestX/Y is run, twice
+	//	TestXX is run, twice
+	//	TestZ is not run
+	//	BenchmarkX is run but only with N=1, once
+	//	BenchmarkXX is run but only with N=1, once
+	//	BenchmarkX/Y is run in full, twice
+	want := `=== RUN   TestX
+=== RUN   TestX/Y
+	x_test.go:6: LOG: X running
+    	x_test.go:8: LOG: Y running
+=== RUN   TestXX
+	z_test.go:10: LOG: XX running
+=== RUN   TestX
+=== RUN   TestX/Y
+	x_test.go:6: LOG: X running
+    	x_test.go:8: LOG: Y running
+=== RUN   TestXX
+	z_test.go:10: LOG: XX running
+--- BENCH: BenchmarkX/Y
+	x_test.go:15: LOG: Y running N=1
+	x_test.go:15: LOG: Y running N=100
+	x_test.go:15: LOG: Y running N=10000
+	x_test.go:15: LOG: Y running N=1000000
+	x_test.go:15: LOG: Y running N=100000000
+	x_test.go:15: LOG: Y running N=2000000000
+--- BENCH: BenchmarkX/Y
+	x_test.go:15: LOG: Y running N=1
+	x_test.go:15: LOG: Y running N=100
+	x_test.go:15: LOG: Y running N=10000
+	x_test.go:15: LOG: Y running N=1000000
+	x_test.go:15: LOG: Y running N=100000000
+	x_test.go:15: LOG: Y running N=2000000000
+--- BENCH: BenchmarkX
+	x_test.go:13: LOG: X running N=1
+--- BENCH: BenchmarkXX
+	z_test.go:18: LOG: XX running N=1
+`
+
+	have := strings.Join(lines, "")
+	if have != want {
+		t.Errorf("reduced output:<<<\n%s>>> want:<<<\n%s>>>", have, want)
+	}
+}
+
+func TestListTests(t *testing.T) {
+	var tg *testgoData
+	testWith := func(listName, expected string) func(*testing.T) {
+		return func(t *testing.T) {
+			tg = testgo(t)
+			defer tg.cleanup()
+			tg.run("test", "./testdata/src/testlist/...", fmt.Sprintf("-list=%s", listName))
+			tg.grepStdout(expected, fmt.Sprintf("-test.list=%s returned %q, expected %s", listName, tg.getStdout(), expected))
+		}
+	}
+
+	t.Run("Test", testWith("Test", "TestSimple"))
+	t.Run("Bench", testWith("Benchmark", "BenchmarkSimple"))
+	t.Run("Example1", testWith("Example", "ExampleSimple"))
+	t.Run("Example2", testWith("Example", "ExampleWithEmptyOutput"))
+}
diff --git a/libgo/go/cmd/go/go_unix_test.go b/libgo/go/cmd/go/go_unix_test.go
index c445a2e..f6e10ca 100644
--- a/libgo/go/cmd/go/go_unix_test.go
+++ b/libgo/go/cmd/go/go_unix_test.go
@@ -19,9 +19,13 @@
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.tempFile("x.go", `package main; func main() {}`)
-	tg.creatingTemp("x")
-	tg.run("build", tg.path("x.go"))
-	fi, err := os.Stat("x")
+	// Make sure artifact will be output to /tmp/... in case the user
+	// has POSIX acl's on their go source tree.
+	// See issue 17909.
+	exe := tg.path("x")
+	tg.creatingTemp(exe)
+	tg.run("build", "-o", exe, tg.path("x.go"))
+	fi, err := os.Stat(exe)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/libgo/go/cmd/go/internal/base/base.go b/libgo/go/cmd/go/internal/base/base.go
new file mode 100644
index 0000000..aff33f7
--- /dev/null
+++ b/libgo/go/cmd/go/internal/base/base.go
@@ -0,0 +1,173 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package base defines shared basic pieces of the go command,
+// in particular logging and the Command structure.
+package base
+
+import (
+	"bytes"
+	"errors"
+	"flag"
+	"fmt"
+	"go/scanner"
+	"log"
+	"os"
+	"os/exec"
+	"strings"
+	"sync"
+
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/str"
+)
+
+// A Command is an implementation of a go command
+// like go build or go fix.
+type Command struct {
+	// Run runs the command.
+	// The args are the arguments after the command name.
+	Run func(cmd *Command, args []string)
+
+	// UsageLine is the one-line usage message.
+	// The first word in the line is taken to be the command name.
+	UsageLine string
+
+	// Short is the short description shown in the 'go help' output.
+	Short string
+
+	// Long is the long message shown in the 'go help <this-command>' output.
+	Long string
+
+	// Flag is a set of flags specific to this command.
+	Flag flag.FlagSet
+
+	// CustomFlags indicates that the command will do its own
+	// flag parsing.
+	CustomFlags bool
+}
+
+// Commands lists the available commands and help topics.
+// The order here is the order in which they are printed by 'go help'.
+var Commands []*Command
+
+// Name returns the command's name: the first word in the usage line.
+func (c *Command) Name() string {
+	name := c.UsageLine
+	i := strings.Index(name, " ")
+	if i >= 0 {
+		name = name[:i]
+	}
+	return name
+}
+
+func (c *Command) Usage() {
+	fmt.Fprintf(os.Stderr, "usage: %s\n\n", c.UsageLine)
+	fmt.Fprintf(os.Stderr, "%s\n", strings.TrimSpace(c.Long))
+	os.Exit(2)
+}
+
+// Runnable reports whether the command can be run; otherwise
+// it is a documentation pseudo-command such as importpath.
+func (c *Command) Runnable() bool {
+	return c.Run != nil
+}
+
+var atExitFuncs []func()
+
+func AtExit(f func()) {
+	atExitFuncs = append(atExitFuncs, f)
+}
+
+func Exit() {
+	for _, f := range atExitFuncs {
+		f()
+	}
+	os.Exit(exitStatus)
+}
+
+func Fatalf(format string, args ...interface{}) {
+	Errorf(format, args...)
+	Exit()
+}
+
+func Errorf(format string, args ...interface{}) {
+	log.Printf(format, args...)
+	SetExitStatus(1)
+}
+
+func ExitIfErrors() {
+	if exitStatus != 0 {
+		Exit()
+	}
+}
+
+var exitStatus = 0
+var exitMu sync.Mutex
+
+func SetExitStatus(n int) {
+	exitMu.Lock()
+	if exitStatus < n {
+		exitStatus = n
+	}
+	exitMu.Unlock()
+}
+
+// Run runs the command, with stdout and stderr
+// connected to the go command's own stdout and stderr.
+// If the command fails, Run reports the error using Errorf.
+func Run(cmdargs ...interface{}) {
+	cmdline := str.StringList(cmdargs...)
+	if cfg.BuildN || cfg.BuildX {
+		fmt.Printf("%s\n", strings.Join(cmdline, " "))
+		if cfg.BuildN {
+			return
+		}
+	}
+
+	cmd := exec.Command(cmdline[0], cmdline[1:]...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		Errorf("%v", err)
+	}
+}
+
+// RunStdin is like run but connects Stdin.
+func RunStdin(cmdline []string) {
+	cmd := exec.Command(cmdline[0], cmdline[1:]...)
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Env = cfg.OrigEnv
+	StartSigHandlers()
+	if err := cmd.Run(); err != nil {
+		Errorf("%v", err)
+	}
+}
+
+// Usage is the usage-reporting function, filled in by package main
+// but here for reference by other packages.
+var Usage func()
+
+// ExpandScanner expands a scanner.List error into all the errors in the list.
+// The default Error method only shows the first error
+// and does not shorten paths.
+func ExpandScanner(err error) error {
+	// Look for parser errors.
+	if err, ok := err.(scanner.ErrorList); ok {
+		// Prepare error with \n before each message.
+		// When printed in something like context: %v
+		// this will put the leading file positions each on
+		// its own line. It will also show all the errors
+		// instead of just the first, as err.Error does.
+		var buf bytes.Buffer
+		for _, e := range err {
+			e.Pos.Filename = ShortPath(e.Pos.Filename)
+			buf.WriteString("\n")
+			buf.WriteString(e.Error())
+		}
+		return errors.New(buf.String())
+	}
+	return err
+}
diff --git a/libgo/go/cmd/go/internal/base/env.go b/libgo/go/cmd/go/internal/base/env.go
new file mode 100644
index 0000000..fcade9d
--- /dev/null
+++ b/libgo/go/cmd/go/internal/base/env.go
@@ -0,0 +1,37 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package base
+
+import "strings"
+
+// EnvForDir returns a copy of the environment
+// suitable for running in the given directory.
+// The environment is the current process's environment
+// but with an updated $PWD, so that an os.Getwd in the
+// child will be faster.
+func EnvForDir(dir string, base []string) []string {
+	// Internally we only use rooted paths, so dir is rooted.
+	// Even if dir is not rooted, no harm done.
+	return MergeEnvLists([]string{"PWD=" + dir}, base)
+}
+
+// MergeEnvLists merges the two environment lists such that
+// variables with the same name in "in" replace those in "out".
+// This always returns a newly allocated slice.
+func MergeEnvLists(in, out []string) []string {
+	out = append([]string(nil), out...)
+NextVar:
+	for _, inkv := range in {
+		k := strings.SplitAfterN(inkv, "=", 2)[0]
+		for i, outkv := range out {
+			if strings.HasPrefix(outkv, k) {
+				out[i] = inkv
+				continue NextVar
+			}
+		}
+		out = append(out, inkv)
+	}
+	return out
+}
diff --git a/libgo/go/cmd/go/internal/base/flag.go b/libgo/go/cmd/go/internal/base/flag.go
new file mode 100644
index 0000000..5e03e64
--- /dev/null
+++ b/libgo/go/cmd/go/internal/base/flag.go
@@ -0,0 +1,35 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package base
+
+import (
+	"flag"
+
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/str"
+)
+
+// A StringsFlag is a command-line flag that interprets its argument
+// as a space-separated list of possibly-quoted strings.
+type StringsFlag []string
+
+func (v *StringsFlag) Set(s string) error {
+	var err error
+	*v, err = str.SplitQuotedFields(s)
+	if *v == nil {
+		*v = []string{}
+	}
+	return err
+}
+
+func (v *StringsFlag) String() string {
+	return "<StringsFlag>"
+}
+
+// AddBuildFlagsNX adds the -n and -x build flags to the flag set.
+func AddBuildFlagsNX(flags *flag.FlagSet) {
+	flags.BoolVar(&cfg.BuildN, "n", false, "")
+	flags.BoolVar(&cfg.BuildX, "x", false, "")
+}
diff --git a/libgo/go/cmd/go/internal/base/path.go b/libgo/go/cmd/go/internal/base/path.go
new file mode 100644
index 0000000..4f12fa8
--- /dev/null
+++ b/libgo/go/cmd/go/internal/base/path.go
@@ -0,0 +1,74 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package base
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+func getwd() string {
+	wd, err := os.Getwd()
+	if err != nil {
+		Fatalf("cannot determine current directory: %v", err)
+	}
+	return wd
+}
+
+var Cwd = getwd()
+
+// ShortPath returns an absolute or relative name for path, whatever is shorter.
+func ShortPath(path string) string {
+	if rel, err := filepath.Rel(Cwd, path); err == nil && len(rel) < len(path) {
+		return rel
+	}
+	return path
+}
+
+// RelPaths returns a copy of paths with absolute paths
+// made relative to the current directory if they would be shorter.
+func RelPaths(paths []string) []string {
+	var out []string
+	// TODO(rsc): Can this use Cwd from above?
+	pwd, _ := os.Getwd()
+	for _, p := range paths {
+		rel, err := filepath.Rel(pwd, p)
+		if err == nil && len(rel) < len(p) {
+			p = rel
+		}
+		out = append(out, p)
+	}
+	return out
+}
+
+// FilterDotUnderscoreFiles returns a slice containing all elements
+// of path whose base name doesn't begin with "." or "_".
+func FilterDotUnderscoreFiles(path []string) []string {
+	var out []string // lazily initialized
+	for i, p := range path {
+		base := filepath.Base(p)
+		if strings.HasPrefix(base, ".") || strings.HasPrefix(base, "_") {
+			if out == nil {
+				out = append(make([]string, 0, len(path)), path[:i]...)
+			}
+			continue
+		}
+		if out != nil {
+			out = append(out, p)
+		}
+	}
+	if out == nil {
+		return path
+	}
+	return out
+}
+
+// IsTestFile reports whether the source file is a set of tests and should therefore
+// be excluded from coverage analysis.
+func IsTestFile(file string) bool {
+	// We don't cover tests, only the code they test.
+	return strings.HasSuffix(file, "_test.go")
+}
diff --git a/libgo/go/cmd/go/signal.go b/libgo/go/cmd/go/internal/base/signal.go
similarity index 66%
rename from libgo/go/cmd/go/signal.go
rename to libgo/go/cmd/go/internal/base/signal.go
index e8ba0d3..54d1187 100644
--- a/libgo/go/cmd/go/signal.go
+++ b/libgo/go/cmd/go/internal/base/signal.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package base
 
 import (
 	"os"
@@ -10,8 +10,8 @@
 	"sync"
 )
 
-// interrupted is closed, if go process is interrupted.
-var interrupted = make(chan struct{})
+// Interrupted is closed when the go command receives an interrupt signal.
+var Interrupted = make(chan struct{})
 
 // processSignals setups signal handler.
 func processSignals() {
@@ -19,13 +19,13 @@
 	signal.Notify(sig, signalsToIgnore...)
 	go func() {
 		<-sig
-		close(interrupted)
+		close(Interrupted)
 	}()
 }
 
 var onceProcessSignals sync.Once
 
-// startSigHandlers start signal handlers.
-func startSigHandlers() {
+// StartSigHandlers starts the signal handlers.
+func StartSigHandlers() {
 	onceProcessSignals.Do(processSignals)
 }
diff --git a/libgo/go/cmd/go/signal_notunix.go b/libgo/go/cmd/go/internal/base/signal_notunix.go
similarity index 60%
rename from libgo/go/cmd/go/signal_notunix.go
rename to libgo/go/cmd/go/internal/base/signal_notunix.go
index 29aa9d8..9e869b0 100644
--- a/libgo/go/cmd/go/signal_notunix.go
+++ b/libgo/go/cmd/go/internal/base/signal_notunix.go
@@ -4,7 +4,7 @@
 
 // +build plan9 windows
 
-package main
+package base
 
 import (
 	"os"
@@ -12,6 +12,6 @@
 
 var signalsToIgnore = []os.Signal{os.Interrupt}
 
-// signalTrace is the signal to send to make a Go program
-// crash with a stack trace.
-var signalTrace os.Signal = nil
+// SignalTrace is the signal to send to make a Go program
+// crash with a stack trace (no such signal in this case).
+var SignalTrace os.Signal = nil
diff --git a/libgo/go/cmd/go/signal_unix.go b/libgo/go/cmd/go/internal/base/signal_unix.go
similarity index 75%
rename from libgo/go/cmd/go/signal_unix.go
rename to libgo/go/cmd/go/internal/base/signal_unix.go
index e86cd46..4ca3da9 100644
--- a/libgo/go/cmd/go/signal_unix.go
+++ b/libgo/go/cmd/go/internal/base/signal_unix.go
@@ -4,7 +4,7 @@
 
 // +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
 
-package main
+package base
 
 import (
 	"os"
@@ -13,6 +13,6 @@
 
 var signalsToIgnore = []os.Signal{os.Interrupt, syscall.SIGQUIT}
 
-// signalTrace is the signal to send to make a Go program
+// SignalTrace is the signal to send to make a Go program
 // crash with a stack trace.
-var signalTrace os.Signal = syscall.SIGQUIT
+var SignalTrace os.Signal = syscall.SIGQUIT
diff --git a/libgo/go/cmd/go/internal/base/tool.go b/libgo/go/cmd/go/internal/base/tool.go
new file mode 100644
index 0000000..c907772
--- /dev/null
+++ b/libgo/go/cmd/go/internal/base/tool.go
@@ -0,0 +1,53 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package base
+
+import (
+	"fmt"
+	"go/build"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"cmd/go/internal/cfg"
+)
+
+// Configuration for finding tool binaries.
+var (
+	ToolGOOS      = runtime.GOOS
+	ToolGOARCH    = runtime.GOARCH
+	ToolIsWindows = ToolGOOS == "windows"
+	ToolDir       = build.ToolDir
+)
+
+const ToolWindowsExtension = ".exe"
+
+// Tool returns the path to the named tool (for example, "vet").
+// If the tool cannot be found, Tool exits the process.
+func Tool(toolName string) string {
+	toolPath := filepath.Join(ToolDir, toolName)
+	if ToolIsWindows {
+		toolPath += ToolWindowsExtension
+	}
+	if len(cfg.BuildToolexec) > 0 {
+		return toolPath
+	}
+	// Give a nice message if there is no tool with that name.
+	if _, err := os.Stat(toolPath); err != nil {
+		if isInGoToolsRepo(toolName) {
+			fmt.Fprintf(os.Stderr, "go tool: no such tool %q; to install:\n\tgo get golang.org/x/tools/cmd/%s\n", toolName, toolName)
+		} else {
+			fmt.Fprintf(os.Stderr, "go tool: no such tool %q\n", toolName)
+		}
+		SetExitStatus(2)
+		Exit()
+	}
+	return toolPath
+}
+
+// TODO: Delete.
+func isInGoToolsRepo(toolName string) bool {
+	return false
+}
diff --git a/libgo/go/cmd/go/bug.go b/libgo/go/cmd/go/internal/bug/bug.go
similarity index 88%
rename from libgo/go/cmd/go/bug.go
rename to libgo/go/cmd/go/internal/bug/bug.go
index 658f6da..963da94 100644
--- a/libgo/go/cmd/go/bug.go
+++ b/libgo/go/cmd/go/internal/bug/bug.go
@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package bug implements the ``go bug'' command.
+package bug
 
 import (
 	"bytes"
@@ -15,9 +16,14 @@
 	"regexp"
 	"runtime"
 	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/envcmd"
+	"cmd/go/internal/web"
 )
 
-var cmdBug = &Command{
+var CmdBug = &base.Command{
 	Run:       runBug,
 	UsageLine: "bug",
 	Short:     "start a bug report",
@@ -28,23 +34,23 @@
 }
 
 func init() {
-	cmdBug.Flag.BoolVar(&buildV, "v", false, "")
+	CmdBug.Flag.BoolVar(&cfg.BuildV, "v", false, "")
 }
 
-func runBug(cmd *Command, args []string) {
+func runBug(cmd *base.Command, args []string) {
 	var buf bytes.Buffer
 	buf.WriteString(bugHeader)
 	inspectGoVersion(&buf)
 	fmt.Fprint(&buf, "#### System details\n\n")
 	fmt.Fprintln(&buf, "```")
 	fmt.Fprintf(&buf, "go version %s %s/%s\n", runtime.Version(), runtime.GOOS, runtime.GOARCH)
-	env := newEnv
-	env = append(env, extraEnvVars()...)
+	env := cfg.CmdEnv
+	env = append(env, envcmd.ExtraEnvVars()...)
 	for _, e := range env {
 		// Hide the TERM environment variable from "go bug".
 		// See issue #18128
-		if e.name != "TERM" {
-			fmt.Fprintf(&buf, "%s=\"%s\"\n", e.name, e.value)
+		if e.Name != "TERM" {
+			fmt.Fprintf(&buf, "%s=\"%s\"\n", e.Name, e.Value)
 		}
 	}
 	printGoDetails(&buf)
@@ -53,8 +59,8 @@
 	fmt.Fprintln(&buf, "```")
 
 	body := buf.String()
-	url := "https://github.com/golang/go/issues/new?body=" + queryEscape(body)
-	if !openBrowser(url) {
+	url := "https://github.com/golang/go/issues/new?body=" + web.QueryEscape(body)
+	if !web.OpenBrowser(url) {
 		fmt.Print("Please file a new issue at golang.org/issue/new using this template:\n\n")
 		fmt.Print(body)
 	}
@@ -97,7 +103,7 @@
 		if err == nil {
 			fmt.Fprintf(w, "/etc/release: %s\n", out)
 		} else {
-			if buildV {
+			if cfg.BuildV {
 				fmt.Printf("failed to read /etc/release: %v\n", err)
 			}
 		}
@@ -114,16 +120,16 @@
 		// Print up to the first newline.
 		fmt.Fprintf(w, "gdb --version: %s\n", firstLine(out))
 	} else {
-		if buildV {
+		if cfg.BuildV {
 			fmt.Printf("failed to run gdb --version: %v\n", err)
 		}
 	}
 }
 
 func inspectGoVersion(w io.Writer) {
-	data, err := httpGET("https://golang.org/VERSION?m=text")
+	data, err := web.Get("https://golang.org/VERSION?m=text")
 	if err != nil {
-		if buildV {
+		if cfg.BuildV {
 			fmt.Printf("failed to read from golang.org/VERSION: %v\n", err)
 		}
 		return
@@ -150,7 +156,7 @@
 	cmd := exec.Command(path, args...)
 	out, err := cmd.Output()
 	if err != nil {
-		if buildV {
+		if cfg.BuildV {
 			fmt.Printf("%s %s: %v\n", path, strings.Join(args, " "), err)
 		}
 		return
diff --git a/libgo/go/cmd/go/internal/buildid/buildid.go b/libgo/go/cmd/go/internal/buildid/buildid.go
new file mode 100644
index 0000000..091c909
--- /dev/null
+++ b/libgo/go/cmd/go/internal/buildid/buildid.go
@@ -0,0 +1,201 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package buildid
+
+import (
+	"bytes"
+	"cmd/go/internal/cfg"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+)
+
+var (
+	errBuildIDToolchain = fmt.Errorf("build ID only supported in gc toolchain")
+	errBuildIDMalformed = fmt.Errorf("malformed object file")
+	errBuildIDUnknown   = fmt.Errorf("lost build ID")
+)
+
+var (
+	bangArch = []byte("!<arch>")
+	pkgdef   = []byte("__.PKGDEF")
+	goobject = []byte("go object ")
+	buildid  = []byte("build id ")
+)
+
+// ReadBuildID reads the build ID from an archive or binary.
+// It only supports the gc toolchain.
+// Other toolchain maintainers should adjust this function.
+func ReadBuildID(name, target string) (id string, err error) {
+	if cfg.BuildToolchainName != "gc" {
+		return "", errBuildIDToolchain
+	}
+
+	// For commands, read build ID directly from binary.
+	if name == "main" {
+		return ReadBuildIDFromBinary(target)
+	}
+
+	// Otherwise, we expect to have an archive (.a) file,
+	// and we can read the build ID from the Go export data.
+	if !strings.HasSuffix(target, ".a") {
+		return "", &os.PathError{Op: "parse", Path: target, Err: errBuildIDUnknown}
+	}
+
+	// Read just enough of the target to fetch the build ID.
+	// The archive is expected to look like:
+	//
+	//	!<arch>
+	//	__.PKGDEF       0           0     0     644     7955      `
+	//	go object darwin amd64 devel X:none
+	//	build id "b41e5c45250e25c9fd5e9f9a1de7857ea0d41224"
+	//
+	// The variable-sized strings are GOOS, GOARCH, and the experiment list (X:none).
+	// Reading the first 1024 bytes should be plenty.
+	f, err := os.Open(target)
+	if err != nil {
+		return "", err
+	}
+	data := make([]byte, 1024)
+	n, err := io.ReadFull(f, data)
+	f.Close()
+
+	if err != nil && n == 0 {
+		return "", err
+	}
+
+	bad := func() (string, error) {
+		return "", &os.PathError{Op: "parse", Path: target, Err: errBuildIDMalformed}
+	}
+
+	// Archive header.
+	for i := 0; ; i++ { // returns during i==3
+		j := bytes.IndexByte(data, '\n')
+		if j < 0 {
+			return bad()
+		}
+		line := data[:j]
+		data = data[j+1:]
+		switch i {
+		case 0:
+			if !bytes.Equal(line, bangArch) {
+				return bad()
+			}
+		case 1:
+			if !bytes.HasPrefix(line, pkgdef) {
+				return bad()
+			}
+		case 2:
+			if !bytes.HasPrefix(line, goobject) {
+				return bad()
+			}
+		case 3:
+			if !bytes.HasPrefix(line, buildid) {
+				// Found the object header, just doesn't have a build id line.
+				// Treat as successful, with empty build id.
+				return "", nil
+			}
+			id, err := strconv.Unquote(string(line[len(buildid):]))
+			if err != nil {
+				return bad()
+			}
+			return id, nil
+		}
+	}
+}
+
+var (
+	goBuildPrefix = []byte("\xff Go build ID: \"")
+	goBuildEnd    = []byte("\"\n \xff")
+
+	elfPrefix = []byte("\x7fELF")
+
+	machoPrefixes = [][]byte{
+		{0xfe, 0xed, 0xfa, 0xce},
+		{0xfe, 0xed, 0xfa, 0xcf},
+		{0xce, 0xfa, 0xed, 0xfe},
+		{0xcf, 0xfa, 0xed, 0xfe},
+	}
+)
+
+var BuildIDReadSize = 32 * 1024 // changed for testing
+
+// ReadBuildIDFromBinary reads the build ID from a binary.
+//
+// ELF binaries store the build ID in a proper PT_NOTE section.
+//
+// Other binary formats are not so flexible. For those, the linker
+// stores the build ID as non-instruction bytes at the very beginning
+// of the text segment, which should appear near the beginning
+// of the file. This is clumsy but fairly portable. Custom locations
+// can be added for other binary types as needed, like we did for ELF.
+func ReadBuildIDFromBinary(filename string) (id string, err error) {
+	if filename == "" {
+		return "", &os.PathError{Op: "parse", Path: filename, Err: errBuildIDUnknown}
+	}
+
+	// Read the first 32 kB of the binary file.
+	// That should be enough to find the build ID.
+	// In ELF files, the build ID is in the leading headers,
+	// which are typically less than 4 kB, not to mention 32 kB.
+	// In Mach-O files, there's no limit, so we have to parse the file.
+	// On other systems, we're trying to read enough that
+	// we get the beginning of the text segment in the read.
+	// The offset where the text segment begins in a hello
+	// world compiled for each different object format today:
+	//
+	//	Plan 9: 0x20
+	//	Windows: 0x600
+	//
+	f, err := os.Open(filename)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	data := make([]byte, BuildIDReadSize)
+	_, err = io.ReadFull(f, data)
+	if err == io.ErrUnexpectedEOF {
+		err = nil
+	}
+	if err != nil {
+		return "", err
+	}
+
+	if bytes.HasPrefix(data, elfPrefix) {
+		return readELFGoBuildID(filename, f, data)
+	}
+	for _, m := range machoPrefixes {
+		if bytes.HasPrefix(data, m) {
+			return readMachoGoBuildID(filename, f, data)
+		}
+	}
+
+	return readRawGoBuildID(filename, data)
+}
+
+// readRawGoBuildID finds the raw build ID stored in text segment data.
+func readRawGoBuildID(filename string, data []byte) (id string, err error) {
+	i := bytes.Index(data, goBuildPrefix)
+	if i < 0 {
+		// Missing. Treat as successful but build ID empty.
+		return "", nil
+	}
+
+	j := bytes.Index(data[i+len(goBuildPrefix):], goBuildEnd)
+	if j < 0 {
+		return "", &os.PathError{Op: "parse", Path: filename, Err: errBuildIDMalformed}
+	}
+
+	quoted := data[i+len(goBuildPrefix)-1 : i+len(goBuildPrefix)+j+1]
+	id, err = strconv.Unquote(string(quoted))
+	if err != nil {
+		return "", &os.PathError{Op: "parse", Path: filename, Err: errBuildIDMalformed}
+	}
+
+	return id, nil
+}
diff --git a/libgo/go/cmd/go/note.go b/libgo/go/cmd/go/internal/buildid/note.go
similarity index 98%
rename from libgo/go/cmd/go/note.go
rename to libgo/go/cmd/go/internal/buildid/note.go
index fae9536..68c91e2 100644
--- a/libgo/go/cmd/go/note.go
+++ b/libgo/go/cmd/go/internal/buildid/note.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package buildid
 
 import (
 	"bytes"
@@ -25,7 +25,7 @@
 	return data, nil
 }
 
-func readELFNote(filename, name string, typ int32) ([]byte, error) {
+func ReadELFNote(filename, name string, typ int32) ([]byte, error) {
 	f, err := elf.Open(filename)
 	if err != nil {
 		return nil, err
diff --git a/libgo/go/cmd/go/internal/cfg/cfg.go b/libgo/go/cmd/go/internal/cfg/cfg.go
new file mode 100644
index 0000000..8257a0e
--- /dev/null
+++ b/libgo/go/cmd/go/internal/cfg/cfg.go
@@ -0,0 +1,134 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cfg holds configuration shared by multiple parts
+// of the go command.
+package cfg
+
+import (
+	"fmt"
+	"go/build"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"cmd/internal/objabi"
+)
+
+// These are general "build flags" used by build and other commands.
+var (
+	BuildA                 bool   // -a flag
+	BuildBuildmode         string // -buildmode flag
+	BuildContext           = build.Default
+	BuildI                 bool               // -i flag
+	BuildLdflags           []string           // -ldflags flag
+	BuildLinkshared        bool               // -linkshared flag
+	BuildMSan              bool               // -msan flag
+	BuildN                 bool               // -n flag
+	BuildO                 string             // -o flag
+	BuildP                 = runtime.NumCPU() // -p flag
+	BuildPkgdir            string             // -pkgdir flag
+	BuildRace              bool               // -race flag
+	BuildToolexec          []string           // -toolexec flag
+	BuildToolchainName     string
+	BuildToolchainCompiler func() string
+	BuildToolchainLinker   func() string
+	BuildV                 bool // -v flag
+	BuildWork              bool // -work flag
+	BuildX                 bool // -x flag
+)
+
+func init() {
+	BuildToolchainCompiler = func() string { return "missing-compiler" }
+	BuildToolchainLinker = func() string { return "missing-linker" }
+}
+
+// An EnvVar is an environment variable Name=Value.
+type EnvVar struct {
+	Name  string
+	Value string
+}
+
+// OrigEnv is the original environment of the program at startup.
+var OrigEnv []string
+
+// CmdEnv is the new environment for running go tool commands.
+// User binaries (during go test or go run) are run with OrigEnv,
+// not CmdEnv.
+var CmdEnv []EnvVar
+
+// Global build parameters (used during package load)
+var (
+	Goarch    = BuildContext.GOARCH
+	Goos      = BuildContext.GOOS
+	ExeSuffix string
+	Gopath    = filepath.SplitList(BuildContext.GOPATH)
+)
+
+func init() {
+	if Goos == "windows" {
+		ExeSuffix = ".exe"
+	}
+}
+
+var (
+	GOROOT    = findGOROOT()
+	GOBIN     = os.Getenv("GOBIN")
+	GOROOTbin = filepath.Join(GOROOT, "bin")
+	GOROOTpkg = filepath.Join(GOROOT, "pkg")
+	GOROOTsrc = filepath.Join(GOROOT, "src")
+
+	// Used in envcmd.MkEnv and build ID computations.
+	GOARM = fmt.Sprint(objabi.GOARM)
+	GO386 = objabi.GO386
+)
+
+// Update build context to use our computed GOROOT.
+func init() {
+	BuildContext.GOROOT = GOROOT
+	// Note that we must use runtime.GOOS and runtime.GOARCH here,
+	// as the tool directory does not move based on environment variables.
+	// This matches the initialization of ToolDir in go/build,
+	// except for using GOROOT rather than runtime.GOROOT().
+	if runtime.Compiler != "gccgo" {
+		build.ToolDir = filepath.Join(GOROOT, "pkg/tool/"+runtime.GOOS+"_"+runtime.GOARCH)
+	}
+}
+
+func findGOROOT() string {
+	if env := os.Getenv("GOROOT"); env != "" {
+		return filepath.Clean(env)
+	}
+	if runtime.Compiler != "gccgo" {
+		exe, err := os.Executable()
+		if err == nil {
+			exe, err = filepath.Abs(exe)
+			if err == nil {
+				if dir := filepath.Join(exe, "../.."); isGOROOT(dir) {
+					return dir
+				}
+				exe, err = filepath.EvalSymlinks(exe)
+				if err == nil {
+					if dir := filepath.Join(exe, "../.."); isGOROOT(dir) {
+						return dir
+					}
+				}
+			}
+		}
+	}
+	return filepath.Clean(runtime.GOROOT())
+}
+
+// isGOROOT reports whether path looks like a GOROOT.
+//
+// It does this by looking for the path/pkg/tool directory,
+// which is necessary for useful operation of the cmd/go tool,
+// and is not typically present in a GOPATH.
+func isGOROOT(path string) bool {
+	stat, err := os.Stat(filepath.Join(path, "pkg", "tool"))
+	if err != nil {
+		return false
+	}
+	return stat.IsDir()
+}
diff --git a/libgo/go/cmd/go/clean.go b/libgo/go/cmd/go/internal/clean/clean.go
similarity index 80%
rename from libgo/go/cmd/go/clean.go
rename to libgo/go/cmd/go/internal/clean/clean.go
index 7b07150..454cac1 100644
--- a/libgo/go/cmd/go/clean.go
+++ b/libgo/go/cmd/go/internal/clean/clean.go
@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package clean implements the ``go clean'' command.
+package clean
 
 import (
 	"fmt"
@@ -10,9 +11,14 @@
 	"os"
 	"path/filepath"
 	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/work"
 )
 
-var cmdClean = &Command{
+var CmdClean = &base.Command{
 	UsageLine: "clean [-i] [-r] [-n] [-x] [build flags] [packages]",
 	Short:     "remove object files",
 	Long: `
@@ -63,24 +69,24 @@
 
 func init() {
 	// break init cycle
-	cmdClean.Run = runClean
+	CmdClean.Run = runClean
 
-	cmdClean.Flag.BoolVar(&cleanI, "i", false, "")
-	cmdClean.Flag.BoolVar(&cleanR, "r", false, "")
+	CmdClean.Flag.BoolVar(&cleanI, "i", false, "")
+	CmdClean.Flag.BoolVar(&cleanR, "r", false, "")
 	// -n and -x are important enough to be
 	// mentioned explicitly in the docs but they
 	// are part of the build flags.
 
-	addBuildFlags(cmdClean)
+	work.AddBuildFlags(CmdClean)
 }
 
-func runClean(cmd *Command, args []string) {
-	for _, pkg := range packagesAndErrors(args) {
+func runClean(cmd *base.Command, args []string) {
+	for _, pkg := range load.PackagesAndErrors(args) {
 		clean(pkg)
 	}
 }
 
-var cleaned = map[*Package]bool{}
+var cleaned = map[*load.Package]bool{}
 
 // TODO: These are dregs left by Makefile-based builds.
 // Eventually, can stop deleting these.
@@ -105,24 +111,24 @@
 	".so": true,
 }
 
-func clean(p *Package) {
+func clean(p *load.Package) {
 	if cleaned[p] {
 		return
 	}
 	cleaned[p] = true
 
 	if p.Dir == "" {
-		errorf("can't load package: %v", p.Error)
+		base.Errorf("can't load package: %v", p.Error)
 		return
 	}
 	dirs, err := ioutil.ReadDir(p.Dir)
 	if err != nil {
-		errorf("go clean %s: %v", p.Dir, err)
+		base.Errorf("go clean %s: %v", p.Dir, err)
 		return
 	}
 
-	var b builder
-	b.print = fmt.Print
+	var b work.Builder
+	b.Print = fmt.Print
 
 	packageFile := map[string]bool{}
 	if p.Name != "main" {
@@ -172,8 +178,8 @@
 		}
 	}
 
-	if buildN || buildX {
-		b.showcmd(p.Dir, "rm -f %s", strings.Join(allRemove, " "))
+	if cfg.BuildN || cfg.BuildX {
+		b.Showcmd(p.Dir, "rm -f %s", strings.Join(allRemove, " "))
 	}
 
 	toRemove := map[string]bool{}
@@ -185,20 +191,20 @@
 		if dir.IsDir() {
 			// TODO: Remove once Makefiles are forgotten.
 			if cleanDir[name] {
-				if buildN || buildX {
-					b.showcmd(p.Dir, "rm -r %s", name)
-					if buildN {
+				if cfg.BuildN || cfg.BuildX {
+					b.Showcmd(p.Dir, "rm -r %s", name)
+					if cfg.BuildN {
 						continue
 					}
 				}
 				if err := os.RemoveAll(filepath.Join(p.Dir, name)); err != nil {
-					errorf("go clean: %v", err)
+					base.Errorf("go clean: %v", err)
 				}
 			}
 			continue
 		}
 
-		if buildN {
+		if cfg.BuildN {
 			continue
 		}
 
@@ -207,17 +213,17 @@
 		}
 	}
 
-	if cleanI && p.target != "" {
-		if buildN || buildX {
-			b.showcmd("", "rm -f %s", p.target)
+	if cleanI && p.Internal.Target != "" {
+		if cfg.BuildN || cfg.BuildX {
+			b.Showcmd("", "rm -f %s", p.Internal.Target)
 		}
-		if !buildN {
-			removeFile(p.target)
+		if !cfg.BuildN {
+			removeFile(p.Internal.Target)
 		}
 	}
 
 	if cleanR {
-		for _, p1 := range p.imports {
+		for _, p1 := range p.Internal.Imports {
 			clean(p1)
 		}
 	}
@@ -231,7 +237,7 @@
 		return
 	}
 	// Windows does not allow deletion of a binary file while it is executing.
-	if toolIsWindows {
+	if base.ToolIsWindows {
 		// Remove lingering ~ file from last attempt.
 		if _, err2 := os.Stat(f + "~"); err2 == nil {
 			os.Remove(f + "~")
@@ -244,5 +250,5 @@
 			return
 		}
 	}
-	errorf("go clean: %v", err)
+	base.Errorf("go clean: %v", err)
 }
diff --git a/libgo/go/cmd/go/internal/cmdflag/flag.go b/libgo/go/cmd/go/internal/cmdflag/flag.go
new file mode 100644
index 0000000..7ab3022
--- /dev/null
+++ b/libgo/go/cmd/go/internal/cmdflag/flag.go
@@ -0,0 +1,123 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cmdflag handles flag processing common to several go tools.
+package cmdflag
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+
+	"cmd/go/internal/base"
+)
+
+// The flag handling part of go commands such as test is large and distracting.
+// We can't use the standard flag package because some of the flags from
+// our command line are for us, and some are for the binary we're running,
+// and some are for both.
+
+// Defn defines a flag we know about.
+type Defn struct {
+	Name       string     // Name on command line.
+	BoolVar    *bool      // If it's a boolean flag, this points to it.
+	Value      flag.Value // The flag.Value represented.
+	PassToTest bool       // Pass to the test binary? Used only by go test.
+	Present    bool       // Flag has been seen.
+}
+
+// IsBool reports whether v is a bool flag.
+func IsBool(v flag.Value) bool {
+	vv, ok := v.(interface {
+		IsBoolFlag() bool
+	})
+	if ok {
+		return vv.IsBoolFlag()
+	}
+	return false
+}
+
+// SetBool sets the addressed boolean to the value.
+func SetBool(cmd string, flag *bool, value string) {
+	x, err := strconv.ParseBool(value)
+	if err != nil {
+		SyntaxError(cmd, "illegal bool flag value "+value)
+	}
+	*flag = x
+}
+
+// SetInt sets the addressed integer to the value.
+func SetInt(cmd string, flag *int, value string) {
+	x, err := strconv.Atoi(value)
+	if err != nil {
+		SyntaxError(cmd, "illegal int flag value "+value)
+	}
+	*flag = x
+}
+
+// SyntaxError reports an argument syntax error and exits the program.
+func SyntaxError(cmd, msg string) {
+	fmt.Fprintf(os.Stderr, "go %s: %s\n", cmd, msg)
+	if cmd == "test" {
+		fmt.Fprintf(os.Stderr, `run "go help %s" or "go help testflag" for more information`+"\n", cmd)
+	} else {
+		fmt.Fprintf(os.Stderr, `run "go help %s" for more information`+"\n", cmd)
+	}
+	os.Exit(2)
+}
+
+// Parse sees if argument i is present in the definitions and if so,
+// returns its definition, value, and whether it consumed an extra word.
+// If the flag begins (cmd+".") it is ignored for the purpose of this function.
+func Parse(cmd string, defns []*Defn, args []string, i int) (f *Defn, value string, extra bool) {
+	arg := args[i]
+	if strings.HasPrefix(arg, "--") { // reduce two minuses to one
+		arg = arg[1:]
+	}
+	switch arg {
+	case "-?", "-h", "-help":
+		base.Usage()
+	}
+	if arg == "" || arg[0] != '-' {
+		return
+	}
+	name := arg[1:]
+	// If there's already a prefix such as "test.", drop it for now.
+	name = strings.TrimPrefix(name, cmd+".")
+	equals := strings.Index(name, "=")
+	if equals >= 0 {
+		value = name[equals+1:]
+		name = name[:equals]
+	}
+	for _, f = range defns {
+		if name == f.Name {
+			// Booleans are special because they have modes -x, -x=true, -x=false.
+			if f.BoolVar != nil || IsBool(f.Value) {
+				if equals < 0 { // Otherwise, it's been set and will be verified in SetBool.
+					value = "true"
+				} else {
+					// verify it parses
+					SetBool(cmd, new(bool), value)
+				}
+			} else { // Non-booleans must have a value.
+				extra = equals < 0
+				if extra {
+					if i+1 >= len(args) {
+						SyntaxError(cmd, "missing argument for flag "+f.Name)
+					}
+					value = args[i+1]
+				}
+			}
+			if f.Present {
+				SyntaxError(cmd, f.Name+" flag may be set only once")
+			}
+			f.Present = true
+			return
+		}
+	}
+	f = nil
+	return
+}
diff --git a/libgo/go/cmd/go/doc.go b/libgo/go/cmd/go/internal/doc/doc.go
similarity index 79%
rename from libgo/go/cmd/go/doc.go
rename to libgo/go/cmd/go/internal/doc/doc.go
index 8299839..d73dd9a 100644
--- a/libgo/go/cmd/go/doc.go
+++ b/libgo/go/cmd/go/internal/doc/doc.go
@@ -2,20 +2,25 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:generate ./mkalldocs.sh
+// Package doc implements the ``go doc'' command.
+package doc
 
-package main
+import (
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+)
 
-var cmdDoc = &Command{
+var CmdDoc = &base.Command{
 	Run:         runDoc,
-	UsageLine:   "doc [-u] [-c] [package|[package.]symbol[.method]]",
+	UsageLine:   "doc [-u] [-c] [package|[package.]symbol[.methodOrField]]",
 	CustomFlags: true,
 	Short:       "show documentation for package or symbol",
 	Long: `
 Doc prints the documentation comments associated with the item identified by its
-arguments (a package, const, func, type, var, or method) followed by a one-line
-summary of each of the first-level items "under" that item (package-level
-declarations for a package, methods for a type, etc.).
+arguments (a package, const, func, type, var, method, or struct field)
+followed by a one-line summary of each of the first-level items "under"
+that item (package-level declarations for a package, methods for a type,
+etc.).
 
 Doc accepts zero, one, or two arguments.
 
@@ -33,9 +38,9 @@
 which is schematically one of these:
 
 	go doc <pkg>
-	go doc <sym>[.<method>]
-	go doc [<pkg>.]<sym>[.<method>]
-	go doc [<pkg>.][<sym>.]<method>
+	go doc <sym>[.<methodOrField>]
+	go doc [<pkg>.]<sym>[.<methodOrField>]
+	go doc [<pkg>.][<sym>.]<methodOrField>
 
 The first item in this list matched by the argument is the one whose documentation
 is printed. (See the examples below.) However, if the argument starts with a capital
@@ -43,7 +48,7 @@
 
 For packages, the order of scanning is determined lexically in breadth-first order.
 That is, the package presented is the one that matches the search and is nearest
-the root and lexically first at its level of the hierarchy.  The GOROOT tree is
+the root and lexically first at its level of the hierarchy. The GOROOT tree is
 always scanned in its entirety before GOPATH.
 
 If there is no package specified or matched, the package in the current
@@ -55,10 +60,10 @@
 elements like . and ... are not implemented by go doc.
 
 When run with two arguments, the first must be a full package path (not just a
-suffix), and the second is a symbol or symbol and method; this is similar to the
-syntax accepted by godoc:
+suffix), and the second is a symbol, or symbol with method or struct field.
+This is similar to the syntax accepted by godoc:
 
-	go doc <pkg> <sym>[.<method>]
+	go doc <pkg> <sym>[.<methodOrField>]
 
 In all forms, when matching symbols, lower-case letters in the argument match
 either case but upper-case letters match exactly. This means that there may be
@@ -109,10 +114,10 @@
 		when showing the package's top-level documentation.
 	-u
 		Show documentation for unexported as well as exported
-		symbols and methods.
+		symbols, methods, and fields.
 `,
 }
 
-func runDoc(cmd *Command, args []string) {
-	run(buildToolExec, tool("doc"), args)
+func runDoc(cmd *base.Command, args []string) {
+	base.Run(cfg.BuildToolexec, base.Tool("doc"), args)
 }
diff --git a/libgo/go/cmd/go/internal/envcmd/env.go b/libgo/go/cmd/go/internal/envcmd/env.go
new file mode 100644
index 0000000..43d4334
--- /dev/null
+++ b/libgo/go/cmd/go/internal/envcmd/env.go
@@ -0,0 +1,178 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package envcmd implements the ``go env'' command.
+package envcmd
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"runtime"
+	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/work"
+)
+
+var CmdEnv = &base.Command{
+	UsageLine: "env [-json] [var ...]",
+	Short:     "print Go environment information",
+	Long: `
+Env prints Go environment information.
+
+By default env prints information as a shell script
+(on Windows, a batch file). If one or more variable
+names is given as arguments, env prints the value of
+each named variable on its own line.
+
+The -json flag prints the environment in JSON format
+instead of as a shell script.
+	`,
+}
+
+func init() {
+	CmdEnv.Run = runEnv // break init cycle
+}
+
+var envJson = CmdEnv.Flag.Bool("json", false, "")
+
+func MkEnv() []cfg.EnvVar {
+	var b work.Builder
+	b.Init()
+
+	env := []cfg.EnvVar{
+		{Name: "GOARCH", Value: cfg.Goarch},
+		{Name: "GOBIN", Value: cfg.GOBIN},
+		{Name: "GOEXE", Value: cfg.ExeSuffix},
+		{Name: "GOHOSTARCH", Value: runtime.GOARCH},
+		{Name: "GOHOSTOS", Value: runtime.GOOS},
+		{Name: "GOOS", Value: cfg.Goos},
+		{Name: "GOPATH", Value: cfg.BuildContext.GOPATH},
+		{Name: "GORACE", Value: os.Getenv("GORACE")},
+		{Name: "GOROOT", Value: cfg.GOROOT},
+		{Name: "GOTOOLDIR", Value: base.ToolDir},
+
+		// disable escape codes in clang errors
+		{Name: "TERM", Value: "dumb"},
+	}
+
+	if work.GccgoBin != "" {
+		env = append(env, cfg.EnvVar{Name: "GCCGO", Value: work.GccgoBin})
+	} else {
+		env = append(env, cfg.EnvVar{Name: "GCCGO", Value: work.GccgoName})
+	}
+
+	switch cfg.Goarch {
+	case "arm":
+		env = append(env, cfg.EnvVar{Name: "GOARM", Value: cfg.GOARM})
+	case "386":
+		env = append(env, cfg.EnvVar{Name: "GO386", Value: cfg.GO386})
+	}
+
+	cmd := b.GccCmd(".")
+	env = append(env, cfg.EnvVar{Name: "CC", Value: cmd[0]})
+	env = append(env, cfg.EnvVar{Name: "GOGCCFLAGS", Value: strings.Join(cmd[3:], " ")})
+	cmd = b.GxxCmd(".")
+	env = append(env, cfg.EnvVar{Name: "CXX", Value: cmd[0]})
+
+	if cfg.BuildContext.CgoEnabled {
+		env = append(env, cfg.EnvVar{Name: "CGO_ENABLED", Value: "1"})
+	} else {
+		env = append(env, cfg.EnvVar{Name: "CGO_ENABLED", Value: "0"})
+	}
+
+	return env
+}
+
+func findEnv(env []cfg.EnvVar, name string) string {
+	for _, e := range env {
+		if e.Name == name {
+			return e.Value
+		}
+	}
+	return ""
+}
+
+// ExtraEnvVars returns environment variables that should not leak into child processes.
+func ExtraEnvVars() []cfg.EnvVar {
+	var b work.Builder
+	b.Init()
+	cppflags, cflags, cxxflags, fflags, ldflags := b.CFlags(&load.Package{})
+	return []cfg.EnvVar{
+		{Name: "CGO_CFLAGS", Value: strings.Join(cflags, " ")},
+		{Name: "CGO_CPPFLAGS", Value: strings.Join(cppflags, " ")},
+		{Name: "CGO_CXXFLAGS", Value: strings.Join(cxxflags, " ")},
+		{Name: "CGO_FFLAGS", Value: strings.Join(fflags, " ")},
+		{Name: "CGO_LDFLAGS", Value: strings.Join(ldflags, " ")},
+		{Name: "PKG_CONFIG", Value: b.PkgconfigCmd()},
+	}
+}
+
+func runEnv(cmd *base.Command, args []string) {
+	env := cfg.CmdEnv
+	env = append(env, ExtraEnvVars()...)
+	if len(args) > 0 {
+		if *envJson {
+			var es []cfg.EnvVar
+			for _, name := range args {
+				e := cfg.EnvVar{Name: name, Value: findEnv(env, name)}
+				es = append(es, e)
+			}
+			printEnvAsJSON(es)
+		} else {
+			for _, name := range args {
+				fmt.Printf("%s\n", findEnv(env, name))
+			}
+		}
+		return
+	}
+
+	if *envJson {
+		printEnvAsJSON(env)
+		return
+	}
+
+	for _, e := range env {
+		if e.Name != "TERM" {
+			switch runtime.GOOS {
+			default:
+				fmt.Printf("%s=\"%s\"\n", e.Name, e.Value)
+			case "plan9":
+				if strings.IndexByte(e.Value, '\x00') < 0 {
+					fmt.Printf("%s='%s'\n", e.Name, strings.Replace(e.Value, "'", "''", -1))
+				} else {
+					v := strings.Split(e.Value, "\x00")
+					fmt.Printf("%s=(", e.Name)
+					for x, s := range v {
+						if x > 0 {
+							fmt.Printf(" ")
+						}
+						fmt.Printf("%s", s)
+					}
+					fmt.Printf(")\n")
+				}
+			case "windows":
+				fmt.Printf("set %s=%s\n", e.Name, e.Value)
+			}
+		}
+	}
+}
+
+func printEnvAsJSON(env []cfg.EnvVar) {
+	m := make(map[string]string)
+	for _, e := range env {
+		if e.Name == "TERM" {
+			continue
+		}
+		m[e.Name] = e.Value
+	}
+	enc := json.NewEncoder(os.Stdout)
+	enc.SetIndent("", "\t")
+	if err := enc.Encode(m); err != nil {
+		base.Fatalf("%s", err)
+	}
+}
diff --git a/libgo/go/cmd/go/fix.go b/libgo/go/cmd/go/internal/fix/fix.go
similarity index 60%
rename from libgo/go/cmd/go/fix.go
rename to libgo/go/cmd/go/internal/fix/fix.go
index 3af7adb..788d49b 100644
--- a/libgo/go/cmd/go/fix.go
+++ b/libgo/go/cmd/go/internal/fix/fix.go
@@ -2,9 +2,17 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package fix implements the ``go fix'' command.
+package fix
 
-var cmdFix = &Command{
+import (
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/str"
+)
+
+var CmdFix = &base.Command{
 	Run:       runFix,
 	UsageLine: "fix [packages]",
 	Short:     "run go tool fix on packages",
@@ -20,11 +28,12 @@
 	`,
 }
 
-func runFix(cmd *Command, args []string) {
-	for _, pkg := range packages(args) {
+func runFix(cmd *base.Command, args []string) {
+	for _, pkg := range load.Packages(args) {
 		// Use pkg.gofiles instead of pkg.Dir so that
 		// the command only applies to this package,
 		// not to packages in subdirectories.
-		run(stringList(buildToolExec, tool("fix"), relPaths(pkg.allgofiles)))
+		files := base.FilterDotUnderscoreFiles(base.RelPaths(pkg.Internal.AllGoFiles))
+		base.Run(str.StringList(cfg.BuildToolexec, base.Tool("fix"), files))
 	}
 }
diff --git a/libgo/go/cmd/go/fmt.go b/libgo/go/cmd/go/internal/fmtcmd/fmt.go
similarity index 61%
rename from libgo/go/cmd/go/fmt.go
rename to libgo/go/cmd/go/internal/fmtcmd/fmt.go
index 4ed7722..0563a04 100644
--- a/libgo/go/cmd/go/fmt.go
+++ b/libgo/go/cmd/go/internal/fmtcmd/fmt.go
@@ -2,24 +2,30 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package fmtcmd implements the ``go fmt'' command.
+package fmtcmd
 
 import (
 	"os"
 	"path/filepath"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/str"
 )
 
 func init() {
-	addBuildFlagsNX(cmdFmt)
+	base.AddBuildFlagsNX(&CmdFmt.Flag)
 }
 
-var cmdFmt = &Command{
+var CmdFmt = &base.Command{
 	Run:       runFmt,
 	UsageLine: "fmt [-n] [-x] [packages]",
 	Short:     "run gofmt on package sources",
 	Long: `
 Fmt runs the command 'gofmt -l -w' on the packages named
-by the import paths.  It prints the names of the files that are modified.
+by the import paths. It prints the names of the files that are modified.
 
 For more about gofmt, see 'go doc cmd/gofmt'.
 For more about specifying packages, see 'go help packages'.
@@ -33,28 +39,29 @@
 	`,
 }
 
-func runFmt(cmd *Command, args []string) {
+func runFmt(cmd *base.Command, args []string) {
 	gofmt := gofmtPath()
-	for _, pkg := range packages(args) {
+	for _, pkg := range load.Packages(args) {
 		// Use pkg.gofiles instead of pkg.Dir so that
 		// the command only applies to this package,
 		// not to packages in subdirectories.
-		run(stringList(gofmt, "-l", "-w", relPaths(pkg.allgofiles)))
+		files := base.FilterDotUnderscoreFiles(base.RelPaths(pkg.Internal.AllGoFiles))
+		base.Run(str.StringList(gofmt, "-l", "-w", files))
 	}
 }
 
 func gofmtPath() string {
 	gofmt := "gofmt"
-	if toolIsWindows {
-		gofmt += toolWindowsExtension
+	if base.ToolIsWindows {
+		gofmt += base.ToolWindowsExtension
 	}
 
-	gofmtPath := filepath.Join(gobin, gofmt)
+	gofmtPath := filepath.Join(cfg.GOBIN, gofmt)
 	if _, err := os.Stat(gofmtPath); err == nil {
 		return gofmtPath
 	}
 
-	gofmtPath = filepath.Join(goroot, "bin", gofmt)
+	gofmtPath = filepath.Join(cfg.GOROOT, "bin", gofmt)
 	if _, err := os.Stat(gofmtPath); err == nil {
 		return gofmtPath
 	}
diff --git a/libgo/go/cmd/go/generate.go b/libgo/go/cmd/go/internal/generate/generate.go
similarity index 91%
rename from libgo/go/cmd/go/generate.go
rename to libgo/go/cmd/go/internal/generate/generate.go
index 2d92a0c..d47c9b7 100644
--- a/libgo/go/cmd/go/generate.go
+++ b/libgo/go/cmd/go/internal/generate/generate.go
@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package generate implements the ``go generate'' command.
+package generate
 
 import (
 	"bufio"
@@ -16,9 +17,14 @@
 	"regexp"
 	"strconv"
 	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/work"
 )
 
-var cmdGenerate = &Command{
+var CmdGenerate = &base.Command{
 	Run:       runGenerate,
 	UsageLine: "generate [-run regexp] [-n] [-v] [-x] [build flags] [file.go... | packages]",
 	Short:     "generate Go files by processing source",
@@ -74,7 +80,7 @@
 As a last step before running the command, any invocations of any
 environment variables with alphanumeric names, such as $GOFILE or
 $HOME, are expanded throughout the command line. The syntax for
-variable expansion is $NAME on all operating systems.  Due to the
+variable expansion is $NAME on all operating systems. Due to the
 order of evaluation, variables are expanded even inside quoted
 strings. If the variable NAME is not set, $NAME expands to the
 empty string.
@@ -131,12 +137,12 @@
 )
 
 func init() {
-	addBuildFlags(cmdGenerate)
-	cmdGenerate.Flag.StringVar(&generateRunFlag, "run", "", "")
+	work.AddBuildFlags(CmdGenerate)
+	CmdGenerate.Flag.StringVar(&generateRunFlag, "run", "", "")
 }
 
-func runGenerate(cmd *Command, args []string) {
-	ignoreImports = true
+func runGenerate(cmd *base.Command, args []string) {
+	load.IgnoreImports = true
 
 	if generateRunFlag != "" {
 		var err error
@@ -146,8 +152,8 @@
 		}
 	}
 	// Even if the arguments are .go files, this loop suffices.
-	for _, pkg := range packages(args) {
-		for _, file := range pkg.gofiles {
+	for _, pkg := range load.Packages(args) {
+		for _, file := range pkg.Internal.GoFiles {
 			if !generate(pkg.Name, file) {
 				break
 			}
@@ -195,13 +201,13 @@
 			if e != stop {
 				panic(e)
 			}
-			setExitStatus(1)
+			base.SetExitStatus(1)
 		}
 	}()
 	g.dir, g.file = filepath.Split(g.path)
 	g.dir = filepath.Clean(g.dir) // No final separator please.
-	if buildV {
-		fmt.Fprintf(os.Stderr, "%s\n", shortPath(g.path))
+	if cfg.BuildV {
+		fmt.Fprintf(os.Stderr, "%s\n", base.ShortPath(g.path))
 	}
 
 	// Scan for lines that start "//go:generate".
@@ -255,16 +261,16 @@
 			continue
 		}
 		// Run the command line.
-		if buildN || buildX {
+		if cfg.BuildN || cfg.BuildX {
 			fmt.Fprintf(os.Stderr, "%s\n", strings.Join(words, " "))
 		}
-		if buildN {
+		if cfg.BuildN {
 			continue
 		}
 		g.exec(words)
 	}
 	if err != nil && err != io.EOF {
-		g.errorf("error reading %s: %s", shortPath(g.path), err)
+		g.errorf("error reading %s: %s", base.ShortPath(g.path), err)
 	}
 	return true
 }
@@ -277,8 +283,8 @@
 // single go:generate command.
 func (g *Generator) setEnv() {
 	g.env = []string{
-		"GOARCH=" + buildContext.GOARCH,
-		"GOOS=" + buildContext.GOOS,
+		"GOARCH=" + cfg.BuildContext.GOARCH,
+		"GOOS=" + cfg.BuildContext.GOOS,
 		"GOFILE=" + g.file,
 		"GOLINE=" + strconv.Itoa(g.lineNum),
 		"GOPACKAGE=" + g.pkg,
@@ -354,7 +360,7 @@
 // It then exits the program (with exit status 1) because generation stops
 // at the first error.
 func (g *Generator) errorf(format string, args ...interface{}) {
-	fmt.Fprintf(os.Stderr, "%s:%d: %s\n", shortPath(g.path), g.lineNum,
+	fmt.Fprintf(os.Stderr, "%s:%d: %s\n", base.ShortPath(g.path), g.lineNum,
 		fmt.Sprintf(format, args...))
 	panic(stop)
 }
@@ -393,7 +399,7 @@
 	cmd.Stderr = os.Stderr
 	// Run the command in the package directory.
 	cmd.Dir = g.dir
-	cmd.Env = mergeEnvLists(g.env, origEnv)
+	cmd.Env = base.MergeEnvLists(g.env, cfg.OrigEnv)
 	err := cmd.Run()
 	if err != nil {
 		g.errorf("running %q: %s", words[0], err)
diff --git a/libgo/go/cmd/go/generate_test.go b/libgo/go/cmd/go/internal/generate/generate_test.go
similarity index 98%
rename from libgo/go/cmd/go/generate_test.go
rename to libgo/go/cmd/go/internal/generate/generate_test.go
index dd116e6..defc153 100644
--- a/libgo/go/cmd/go/generate_test.go
+++ b/libgo/go/cmd/go/internal/generate/generate_test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package generate
 
 import (
 	"reflect"
diff --git a/libgo/go/cmd/go/discovery.go b/libgo/go/cmd/go/internal/get/discovery.go
similarity index 88%
rename from libgo/go/cmd/go/discovery.go
rename to libgo/go/cmd/go/internal/get/discovery.go
index b60eaef..b2918db 100644
--- a/libgo/go/cmd/go/discovery.go
+++ b/libgo/go/cmd/go/internal/get/discovery.go
@@ -2,14 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !cmd_go_bootstrap
-
-// This code is compiled into the real 'go' binary, but it is not
-// compiled into the binary that is built during all.bash, so as
-// to avoid needing to build net (and thus use cgo) during the
-// bootstrap process.
-
-package main
+package get
 
 import (
 	"encoding/xml"
diff --git a/libgo/go/cmd/go/get.go b/libgo/go/cmd/go/internal/get/get.go
similarity index 74%
rename from libgo/go/cmd/go/get.go
rename to libgo/go/cmd/go/internal/get/get.go
index 6fb4235..5503211 100644
--- a/libgo/go/cmd/go/get.go
+++ b/libgo/go/cmd/go/internal/get/get.go
@@ -2,20 +2,26 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package get implements the ``go get'' command.
+package get
 
 import (
 	"fmt"
 	"go/build"
 	"os"
 	"path/filepath"
-	"regexp"
 	"runtime"
-	"strconv"
 	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/str"
+	"cmd/go/internal/web"
+	"cmd/go/internal/work"
 )
 
-var cmdGet = &Command{
+var CmdGet = &base.Command{
 	UsageLine: "get [-d] [-f] [-fix] [-insecure] [-t] [-u] [build flags] [packages]",
 	Short:     "download and install packages and dependencies",
 	Long: `
@@ -40,7 +46,7 @@
 the tests for the specified packages.
 
 The -u flag instructs get to use the network to update the named packages
-and their dependencies.  By default, get uses the network to check out
+and their dependencies. By default, get uses the network to check out
 missing packages but does not use it to look for updates to existing packages.
 
 The -v flag enables verbose progress and debug output.
@@ -54,8 +60,8 @@
 When checking out or updating a package, get looks for a branch or tag
 that matches the locally installed version of Go. The most important
 rule is that if the local installation is running version "go1", get
-searches for a branch or tag named "go1". If no such version exists it
-retrieves the most recent version of the package.
+searches for a branch or tag named "go1". If no such version exists
+it retrieves the default branch of the package.
 
 When go get checks out or updates a Git repository,
 it also updates any git submodules referenced by the repository.
@@ -71,21 +77,24 @@
 	`,
 }
 
-var getD = cmdGet.Flag.Bool("d", false, "")
-var getF = cmdGet.Flag.Bool("f", false, "")
-var getT = cmdGet.Flag.Bool("t", false, "")
-var getU = cmdGet.Flag.Bool("u", false, "")
-var getFix = cmdGet.Flag.Bool("fix", false, "")
-var getInsecure = cmdGet.Flag.Bool("insecure", false, "")
+var getD = CmdGet.Flag.Bool("d", false, "")
+var getF = CmdGet.Flag.Bool("f", false, "")
+var getT = CmdGet.Flag.Bool("t", false, "")
+var getU = CmdGet.Flag.Bool("u", false, "")
+var getFix = CmdGet.Flag.Bool("fix", false, "")
+var getInsecure = CmdGet.Flag.Bool("insecure", false, "")
 
 func init() {
-	addBuildFlags(cmdGet)
-	cmdGet.Run = runGet // break init loop
+	work.AddBuildFlags(CmdGet)
+	CmdGet.Run = runGet // break init loop
 }
 
-func runGet(cmd *Command, args []string) {
+func runGet(cmd *base.Command, args []string) {
+	work.InstrumentInit()
+	work.BuildModeInit()
+
 	if *getF && !*getU {
-		fatalf("go get: cannot use -f flag without -u")
+		base.Fatalf("go get: cannot use -f flag without -u")
 	}
 
 	// Disable any prompting for passwords by Git.
@@ -115,17 +124,17 @@
 		os.Setenv("GIT_SSH_COMMAND", "ssh -o ControlMaster=no")
 	}
 
-	// Phase 1.  Download/update.
-	var stk importStack
+	// Phase 1. Download/update.
+	var stk load.ImportStack
 	mode := 0
 	if *getT {
-		mode |= getTestDeps
+		mode |= load.GetTestDeps
 	}
 	args = downloadPaths(args)
 	for _, arg := range args {
 		download(arg, nil, &stk, mode)
 	}
-	exitIfErrors()
+	base.ExitIfErrors()
 
 	// Phase 2. Rescan packages and re-evaluate args list.
 
@@ -134,22 +143,18 @@
 	// the information will be recomputed. Instead of keeping
 	// track of the reverse dependency information, evict
 	// everything.
-	for name := range packageCache {
-		delete(packageCache, name)
-	}
+	load.ClearPackageCache()
 
 	// In order to rebuild packages information completely,
 	// we need to clear commands cache. Command packages are
 	// referring to evicted packages from the package cache.
 	// This leads to duplicated loads of the standard packages.
-	for name := range cmdCache {
-		delete(cmdCache, name)
-	}
+	load.ClearCmdCache()
 
-	args = importPaths(args)
-	packagesForBuild(args)
+	args = load.ImportPaths(args)
+	load.PackagesForBuild(args)
 
-	// Phase 3.  Install.
+	// Phase 3. Install.
 	if *getD {
 		// Download only.
 		// Check delayed until now so that importPaths
@@ -157,7 +162,7 @@
 		return
 	}
 
-	installPackages(args, true)
+	work.InstallPackages(args, true)
 }
 
 // downloadPaths prepares the list of paths to pass to download.
@@ -166,7 +171,7 @@
 // in the hope that we can figure out the repository from the
 // initial ...-free prefix.
 func downloadPaths(args []string) []string {
-	args = importPathsNoDotExpansion(args)
+	args = load.ImportPathsNoDotExpansion(args)
 	var out []string
 	for _, a := range args {
 		if strings.Contains(a, "...") {
@@ -175,9 +180,9 @@
 			// warnings. They will be printed by the
 			// eventual call to importPaths instead.
 			if build.IsLocalImport(a) {
-				expand = matchPackagesInFS(a)
+				expand = load.MatchPackagesInFS(a)
 			} else {
-				expand = matchPackages(a)
+				expand = load.MatchPackages(a)
 			}
 			if len(expand) > 0 {
 				out = append(out, expand...)
@@ -204,21 +209,21 @@
 
 // download runs the download half of the get command
 // for the package named by the argument.
-func download(arg string, parent *Package, stk *importStack, mode int) {
-	if mode&useVendor != 0 {
+func download(arg string, parent *load.Package, stk *load.ImportStack, mode int) {
+	if mode&load.UseVendor != 0 {
 		// Caller is responsible for expanding vendor paths.
 		panic("internal error: download mode has useVendor set")
 	}
-	load := func(path string, mode int) *Package {
+	load1 := func(path string, mode int) *load.Package {
 		if parent == nil {
-			return loadPackage(path, stk)
+			return load.LoadPackage(path, stk)
 		}
-		return loadImport(path, parent.Dir, parent, stk, nil, mode)
+		return load.LoadImport(path, parent.Dir, parent, stk, nil, mode)
 	}
 
-	p := load(arg, mode)
-	if p.Error != nil && p.Error.hard {
-		errorf("%s", p.Error)
+	p := load1(arg, mode)
+	if p.Error != nil && p.Error.Hard {
+		base.Errorf("%s", p.Error)
 		return
 	}
 
@@ -240,26 +245,26 @@
 	// Only process each package once.
 	// (Unless we're fetching test dependencies for this package,
 	// in which case we want to process it again.)
-	if downloadCache[arg] && mode&getTestDeps == 0 {
+	if downloadCache[arg] && mode&load.GetTestDeps == 0 {
 		return
 	}
 	downloadCache[arg] = true
 
-	pkgs := []*Package{p}
+	pkgs := []*load.Package{p}
 	wildcardOkay := len(*stk) == 0
 	isWildcard := false
 
 	// Download if the package is missing, or update if we're using -u.
 	if p.Dir == "" || *getU {
 		// The actual download.
-		stk.push(arg)
+		stk.Push(arg)
 		err := downloadPackage(p)
 		if err != nil {
-			errorf("%s", &PackageError{ImportStack: stk.copy(), Err: err.Error()})
-			stk.pop()
+			base.Errorf("%s", &load.PackageError{ImportStack: stk.Copy(), Err: err.Error()})
+			stk.Pop()
 			return
 		}
-		stk.pop()
+		stk.Pop()
 
 		args := []string{arg}
 		// If the argument has a wildcard in it, re-evaluate the wildcard.
@@ -267,31 +272,25 @@
 		// for p has been replaced in the package cache.
 		if wildcardOkay && strings.Contains(arg, "...") {
 			if build.IsLocalImport(arg) {
-				args = matchPackagesInFS(arg)
+				args = load.MatchPackagesInFS(arg)
 			} else {
-				args = matchPackages(arg)
+				args = load.MatchPackages(arg)
 			}
 			isWildcard = true
 		}
 
 		// Clear all relevant package cache entries before
 		// doing any new loads.
-		for _, arg := range args {
-			p := packageCache[arg]
-			if p != nil {
-				delete(packageCache, p.Dir)
-				delete(packageCache, p.ImportPath)
-			}
-		}
+		load.ClearPackageCachePartial(args)
 
 		pkgs = pkgs[:0]
 		for _, arg := range args {
 			// Note: load calls loadPackage or loadImport,
 			// which push arg onto stk already.
 			// Do not push here too, or else stk will say arg imports arg.
-			p := load(arg, mode)
+			p := load1(arg, mode)
 			if p.Error != nil {
-				errorf("%s", p.Error)
+				base.Errorf("%s", p.Error)
 				continue
 			}
 			pkgs = append(pkgs, p)
@@ -302,12 +301,13 @@
 	// due to wildcard expansion.
 	for _, p := range pkgs {
 		if *getFix {
-			run(buildToolExec, stringList(tool("fix"), relPaths(p.allgofiles)))
+			files := base.FilterDotUnderscoreFiles(base.RelPaths(p.Internal.AllGoFiles))
+			base.Run(cfg.BuildToolexec, str.StringList(base.Tool("fix"), files))
 
 			// The imports might have changed, so reload again.
-			p = reloadPackage(arg, stk)
+			p = load.ReloadPackage(arg, stk)
 			if p.Error != nil {
-				errorf("%s", p.Error)
+				base.Errorf("%s", p.Error)
 				return
 			}
 		}
@@ -315,16 +315,16 @@
 		if isWildcard {
 			// Report both the real package and the
 			// wildcard in any error message.
-			stk.push(p.ImportPath)
+			stk.Push(p.ImportPath)
 		}
 
 		// Process dependencies, now that we know what they are.
 		imports := p.Imports
-		if mode&getTestDeps != 0 {
+		if mode&load.GetTestDeps != 0 {
 			// Process test dependencies when -t is specified.
 			// (But don't get test dependencies for test dependencies:
 			// we always pass mode 0 to the recursive calls below.)
-			imports = stringList(imports, p.TestImports, p.XTestImports)
+			imports = str.StringList(imports, p.TestImports, p.XTestImports)
 		}
 		for i, path := range imports {
 			if path == "C" {
@@ -332,19 +332,19 @@
 			}
 			// Fail fast on import naming full vendor path.
 			// Otherwise expand path as needed for test imports.
-			// Note that p.Imports can have additional entries beyond p.build.Imports.
+			// Note that p.Imports can have additional entries beyond p.Internal.Build.Imports.
 			orig := path
-			if i < len(p.build.Imports) {
-				orig = p.build.Imports[i]
+			if i < len(p.Internal.Build.Imports) {
+				orig = p.Internal.Build.Imports[i]
 			}
-			if j, ok := findVendor(orig); ok {
-				stk.push(path)
-				err := &PackageError{
-					ImportStack: stk.copy(),
+			if j, ok := load.FindVendor(orig); ok {
+				stk.Push(path)
+				err := &load.PackageError{
+					ImportStack: stk.Copy(),
 					Err:         "must be imported as " + path[j+len("vendor/"):],
 				}
-				stk.pop()
-				errorf("%s", err)
+				stk.Pop()
+				base.Errorf("%s", err)
 				continue
 			}
 			// If this is a test import, apply vendor lookup now.
@@ -352,34 +352,34 @@
 			// download does caching based on the value of path,
 			// so it must be the fully qualified path already.
 			if i >= len(p.Imports) {
-				path = vendoredImportPath(p, path)
+				path = load.VendoredImportPath(p, path)
 			}
 			download(path, p, stk, 0)
 		}
 
 		if isWildcard {
-			stk.pop()
+			stk.Pop()
 		}
 	}
 }
 
 // downloadPackage runs the create or download command
 // to make the first copy of or update a copy of the given package.
-func downloadPackage(p *Package) error {
+func downloadPackage(p *load.Package) error {
 	var (
 		vcs            *vcsCmd
 		repo, rootPath string
 		err            error
 	)
 
-	security := secure
+	security := web.Secure
 	if *getInsecure {
-		security = insecure
+		security = web.Insecure
 	}
 
-	if p.build.SrcRoot != "" {
+	if p.Internal.Build.SrcRoot != "" {
 		// Directory exists. Look for checkout along path to src.
-		vcs, rootPath, err = vcsFromDir(p.Dir, p.build.SrcRoot)
+		vcs, rootPath, err = vcsFromDir(p.Dir, p.Internal.Build.SrcRoot)
 		if err != nil {
 			return err
 		}
@@ -387,7 +387,7 @@
 
 		// Double-check where it came from.
 		if *getU && vcs.remoteRepo != nil {
-			dir := filepath.Join(p.build.SrcRoot, filepath.FromSlash(rootPath))
+			dir := filepath.Join(p.Internal.Build.SrcRoot, filepath.FromSlash(rootPath))
 			remote, err := vcs.remoteRepo(vcs, dir)
 			if err != nil {
 				return err
@@ -421,31 +421,31 @@
 		return fmt.Errorf("cannot download, %v uses insecure protocol", repo)
 	}
 
-	if p.build.SrcRoot == "" {
+	if p.Internal.Build.SrcRoot == "" {
 		// Package not found. Put in first directory of $GOPATH.
-		list := filepath.SplitList(buildContext.GOPATH)
+		list := filepath.SplitList(cfg.BuildContext.GOPATH)
 		if len(list) == 0 {
 			return fmt.Errorf("cannot download, $GOPATH not set. For more details see: 'go help gopath'")
 		}
 		// Guard against people setting GOPATH=$GOROOT.
-		if filepath.Clean(list[0]) == filepath.Clean(goroot) {
+		if filepath.Clean(list[0]) == filepath.Clean(cfg.GOROOT) {
 			return fmt.Errorf("cannot download, $GOPATH must not be set to $GOROOT. For more details see: 'go help gopath'")
 		}
 		if _, err := os.Stat(filepath.Join(list[0], "src/cmd/go/alldocs.go")); err == nil {
 			return fmt.Errorf("cannot download, %s is a GOROOT, not a GOPATH. For more details see: 'go help gopath'", list[0])
 		}
-		p.build.Root = list[0]
-		p.build.SrcRoot = filepath.Join(list[0], "src")
-		p.build.PkgRoot = filepath.Join(list[0], "pkg")
+		p.Internal.Build.Root = list[0]
+		p.Internal.Build.SrcRoot = filepath.Join(list[0], "src")
+		p.Internal.Build.PkgRoot = filepath.Join(list[0], "pkg")
 	}
-	root := filepath.Join(p.build.SrcRoot, filepath.FromSlash(rootPath))
+	root := filepath.Join(p.Internal.Build.SrcRoot, filepath.FromSlash(rootPath))
 	// If we've considered this repository already, don't do it again.
 	if downloadRootCache[root] {
 		return nil
 	}
 	downloadRootCache[root] = true
 
-	if buildV {
+	if cfg.BuildV {
 		fmt.Fprintf(os.Stderr, "%s (download)\n", rootPath)
 	}
 
@@ -464,7 +464,7 @@
 			return fmt.Errorf("%s exists but %s does not - stale checkout?", root, meta)
 		}
 
-		_, err := os.Stat(p.build.Root)
+		_, err := os.Stat(p.Internal.Build.Root)
 		gopathExisted := err == nil
 
 		// Some version control tools require the parent of the target to exist.
@@ -472,8 +472,8 @@
 		if err = os.MkdirAll(parent, 0777); err != nil {
 			return err
 		}
-		if buildV && !gopathExisted && p.build.Root == buildContext.GOPATH {
-			fmt.Fprintf(os.Stderr, "created GOPATH=%s; see 'go help gopath'\n", p.build.Root)
+		if cfg.BuildV && !gopathExisted && p.Internal.Build.Root == cfg.BuildContext.GOPATH {
+			fmt.Fprintf(os.Stderr, "created GOPATH=%s; see 'go help gopath'\n", p.Internal.Build.Root)
 		}
 
 		if err = vcs.create(root, repo); err != nil {
@@ -486,7 +486,7 @@
 		}
 	}
 
-	if buildN {
+	if cfg.BuildN {
 		// Do not show tag sync in -n; it's noise more than anything,
 		// and since we're not running commands, no tag will be found.
 		// But avoid printing nothing.
@@ -510,14 +510,6 @@
 	return nil
 }
 
-// goTag matches go release tags such as go1 and go1.2.3.
-// The numbers involved must be small (at most 4 digits),
-// have no unnecessary leading zeros, and the version cannot
-// end in .0 - it is go1, not go1.0 or go1.0.0.
-var goTag = regexp.MustCompile(
-	`^go((0|[1-9][0-9]{0,3})\.)*([1-9][0-9]{0,3})$`,
-)
-
 // selectTag returns the closest matching tag for a given version.
 // Closest means the latest one that is not after the current release.
 // Version "goX" (or "goX.Y" or "goX.Y.Z") matches tags of the same form.
@@ -525,7 +517,7 @@
 // Version "weekly.YYYY-MM-DD" matches tags like "go.weekly.YYYY-MM-DD".
 //
 // NOTE(rsc): Eventually we will need to decide on some logic here.
-// For now, there is only "go1".  This matches the docs in go help get.
+// For now, there is only "go1". This matches the docs in go help get.
 func selectTag(goVersion string, tags []string) (match string) {
 	for _, t := range tags {
 		if t == "go1" {
@@ -533,56 +525,4 @@
 		}
 	}
 	return ""
-
-	/*
-		if goTag.MatchString(goVersion) {
-			v := goVersion
-			for _, t := range tags {
-				if !goTag.MatchString(t) {
-					continue
-				}
-				if cmpGoVersion(match, t) < 0 && cmpGoVersion(t, v) <= 0 {
-					match = t
-				}
-			}
-		}
-
-		return match
-	*/
-}
-
-// cmpGoVersion returns -1, 0, +1 reporting whether
-// x < y, x == y, or x > y.
-func cmpGoVersion(x, y string) int {
-	// Malformed strings compare less than well-formed strings.
-	if !goTag.MatchString(x) {
-		return -1
-	}
-	if !goTag.MatchString(y) {
-		return +1
-	}
-
-	// Compare numbers in sequence.
-	xx := strings.Split(x[len("go"):], ".")
-	yy := strings.Split(y[len("go"):], ".")
-
-	for i := 0; i < len(xx) && i < len(yy); i++ {
-		// The Atoi are guaranteed to succeed
-		// because the versions match goTag.
-		xi, _ := strconv.Atoi(xx[i])
-		yi, _ := strconv.Atoi(yy[i])
-		if xi < yi {
-			return -1
-		} else if xi > yi {
-			return +1
-		}
-	}
-
-	if len(xx) < len(yy) {
-		return -1
-	}
-	if len(xx) > len(yy) {
-		return +1
-	}
-	return 0
 }
diff --git a/libgo/go/cmd/go/internal/get/pkg_test.go b/libgo/go/cmd/go/internal/get/pkg_test.go
new file mode 100644
index 0000000..b8937a5
--- /dev/null
+++ b/libgo/go/cmd/go/internal/get/pkg_test.go
@@ -0,0 +1,83 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package get
+
+import (
+	"cmd/go/internal/str"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+var foldDupTests = []struct {
+	list   []string
+	f1, f2 string
+}{
+	{str.StringList("math/rand", "math/big"), "", ""},
+	{str.StringList("math", "strings"), "", ""},
+	{str.StringList("strings"), "", ""},
+	{str.StringList("strings", "strings"), "strings", "strings"},
+	{str.StringList("Rand", "rand", "math", "math/rand", "math/Rand"), "Rand", "rand"},
+}
+
+func TestFoldDup(t *testing.T) {
+	for _, tt := range foldDupTests {
+		f1, f2 := str.FoldDup(tt.list)
+		if f1 != tt.f1 || f2 != tt.f2 {
+			t.Errorf("foldDup(%q) = %q, %q, want %q, %q", tt.list, f1, f2, tt.f1, tt.f2)
+		}
+	}
+}
+
+var parseMetaGoImportsTests = []struct {
+	in  string
+	out []metaImport
+}{
+	{
+		`<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">`,
+		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
+	},
+	{
+		`<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">
+		<meta name="go-import" content="baz/quux git http://github.com/rsc/baz/quux">`,
+		[]metaImport{
+			{"foo/bar", "git", "https://github.com/rsc/foo/bar"},
+			{"baz/quux", "git", "http://github.com/rsc/baz/quux"},
+		},
+	},
+	{
+		`<head>
+		<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">
+		</head>`,
+		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
+	},
+	{
+		`<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">
+		<body>`,
+		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
+	},
+	{
+		`<!doctype html><meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">`,
+		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
+	},
+	{
+		// XML doesn't like <div style=position:relative>.
+		`<!doctype html><title>Page Not Found</title><meta name=go-import content="chitin.io/chitin git https://github.com/chitin-io/chitin"><div style=position:relative>DRAFT</div>`,
+		[]metaImport{{"chitin.io/chitin", "git", "https://github.com/chitin-io/chitin"}},
+	},
+}
+
+func TestParseMetaGoImports(t *testing.T) {
+	for i, tt := range parseMetaGoImportsTests {
+		out, err := parseMetaGoImports(strings.NewReader(tt.in))
+		if err != nil {
+			t.Errorf("test#%d: %v", i, err)
+			continue
+		}
+		if !reflect.DeepEqual(out, tt.out) {
+			t.Errorf("test#%d:\n\thave %q\n\twant %q", i, out, tt.out)
+		}
+	}
+}
diff --git a/libgo/go/cmd/go/tag_test.go b/libgo/go/cmd/go/internal/get/tag_test.go
similarity index 99%
rename from libgo/go/cmd/go/tag_test.go
rename to libgo/go/cmd/go/internal/get/tag_test.go
index 6649bd6..9a25dfa 100644
--- a/libgo/go/cmd/go/tag_test.go
+++ b/libgo/go/cmd/go/internal/get/tag_test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package get
 
 import "testing"
 
diff --git a/libgo/go/cmd/go/vcs.go b/libgo/go/cmd/go/internal/get/vcs.go
similarity index 94%
rename from libgo/go/cmd/go/vcs.go
rename to libgo/go/cmd/go/internal/get/vcs.go
index fcdce22..71d0b51 100644
--- a/libgo/go/cmd/go/vcs.go
+++ b/libgo/go/cmd/go/internal/get/vcs.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package get
 
 import (
 	"bytes"
@@ -18,6 +18,10 @@
 	"regexp"
 	"strings"
 	"sync"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/web"
 )
 
 // A vcsCmd describes how to use a version control system
@@ -298,15 +302,20 @@
 	out := string(outb)
 
 	// Expect:
-	// ...
-	// Repository Root: <URL>
-	// ...
-
-	i := strings.Index(out, "\nRepository Root: ")
+	//
+	//	 ...
+	// 	URL: <URL>
+	// 	...
+	//
+	// Note that we're not using the Repository Root line,
+	// because svn allows checking out subtrees.
+	// The URL will be the URL of the subtree (what we used with 'svn co')
+	// while the Repository Root may be a much higher parent.
+	i := strings.Index(out, "\nURL: ")
 	if i < 0 {
 		return "", fmt.Errorf("unable to parse output of svn info")
 	}
-	out = out[i+len("\nRepository Root: "):]
+	out = out[i+len("\nURL: "):]
 	i = strings.Index(out, "\n")
 	if i < 0 {
 		return "", fmt.Errorf("unable to parse output of svn info")
@@ -320,7 +329,7 @@
 }
 
 // run runs the command line cmd in the given directory.
-// keyval is a list of key, value pairs.  run expands
+// keyval is a list of key, value pairs. run expands
 // instances of {key} in cmd into value, but only after
 // splitting cmd into individual arguments.
 // If an error occurs, run prints the command line and the
@@ -372,8 +381,8 @@
 
 	cmd := exec.Command(v.cmd, args...)
 	cmd.Dir = dir
-	cmd.Env = envForDir(cmd.Dir, os.Environ())
-	if buildX {
+	cmd.Env = base.EnvForDir(cmd.Dir, os.Environ())
+	if cfg.BuildX {
 		fmt.Printf("cd %s\n", dir)
 		fmt.Printf("%s %s\n", v.cmd, strings.Join(args, " "))
 	}
@@ -383,7 +392,7 @@
 	err = cmd.Run()
 	out := buf.Bytes()
 	if err != nil {
-		if verbose || buildV {
+		if verbose || cfg.BuildV {
 			fmt.Fprintf(os.Stderr, "# cd %s; %s %s\n", dir, v.cmd, strings.Join(args, " "))
 			os.Stderr.Write(out)
 		}
@@ -535,19 +544,9 @@
 
 var httpPrefixRE = regexp.MustCompile(`^https?:`)
 
-// securityMode specifies whether a function should make network
-// calls using insecure transports (eg, plain text HTTP).
-// The zero value is "secure".
-type securityMode int
-
-const (
-	secure securityMode = iota
-	insecure
-)
-
 // repoRootForImportPath analyzes importPath to determine the
 // version control system, and code repository to use.
-func repoRootForImportPath(importPath string, security securityMode) (*repoRoot, error) {
+func repoRootForImportPath(importPath string, security web.SecurityMode) (*repoRoot, error) {
 	rr, err := repoRootFromVCSPaths(importPath, "", security, vcsPaths)
 	if err == errUnknownSite {
 		// If there are wildcards, look up the thing before the wildcard,
@@ -583,7 +582,7 @@
 // repoRootFromVCSPaths attempts to map importPath to a repoRoot
 // using the mappings defined in vcsPaths.
 // If scheme is non-empty, that scheme is forced.
-func repoRootFromVCSPaths(importPath, scheme string, security securityMode, vcsPaths []*vcsPath) (*repoRoot, error) {
+func repoRootFromVCSPaths(importPath, scheme string, security web.SecurityMode, vcsPaths []*vcsPath) (*repoRoot, error) {
 	// A common error is to use https://packagepath because that's what
 	// hg and git require. Diagnose this helpfully.
 	if loc := httpPrefixRE.FindStringIndex(importPath); loc != nil {
@@ -633,7 +632,7 @@
 				match["repo"] = scheme + "://" + match["repo"]
 			} else {
 				for _, scheme := range vcs.scheme {
-					if security == secure && !vcs.isSecureScheme(scheme) {
+					if security == web.Secure && !vcs.isSecureScheme(scheme) {
 						continue
 					}
 					if vcs.ping(scheme, match["repo"]) == nil {
@@ -657,7 +656,7 @@
 // statically known by repoRootForImportPathStatic.
 //
 // This handles custom import paths like "name.tld/pkg/foo" or just "name.tld".
-func repoRootForImportDynamic(importPath string, security securityMode) (*repoRoot, error) {
+func repoRootForImportDynamic(importPath string, security web.SecurityMode) (*repoRoot, error) {
 	slash := strings.Index(importPath, "/")
 	if slash < 0 {
 		slash = len(importPath)
@@ -666,10 +665,10 @@
 	if !strings.Contains(host, ".") {
 		return nil, errors.New("import path does not begin with hostname")
 	}
-	urlStr, body, err := httpsOrHTTP(importPath, security)
+	urlStr, body, err := web.GetMaybeInsecure(importPath, security)
 	if err != nil {
 		msg := "https fetch: %v"
-		if security == insecure {
+		if security == web.Insecure {
 			msg = "http/" + msg
 		}
 		return nil, fmt.Errorf(msg, err)
@@ -687,17 +686,17 @@
 		}
 		return nil, fmt.Errorf("parse %s: no go-import meta tags (%s)", urlStr, err)
 	}
-	if buildV {
+	if cfg.BuildV {
 		log.Printf("get %q: found meta tag %#v at %s", importPath, mmi, urlStr)
 	}
 	// If the import was "uni.edu/bob/project", which said the
 	// prefix was "uni.edu" and the RepoRoot was "evilroot.com",
 	// make sure we don't trust Bob and check out evilroot.com to
 	// "uni.edu" yet (possibly overwriting/preempting another
-	// non-evil student).  Instead, first verify the root and see
+	// non-evil student). Instead, first verify the root and see
 	// if it matches Bob's claim.
 	if mmi.Prefix != importPath {
-		if buildV {
+		if cfg.BuildV {
 			log.Printf("get %q: verifying non-authoritative meta tag", importPath)
 		}
 		urlStr0 := urlStr
@@ -741,7 +740,7 @@
 // It is an error if no imports are found.
 // urlStr will still be valid if err != nil.
 // The returned urlStr will be of the form "https://golang.org/x/tools?go-get=1"
-func metaImportsForPrefix(importPrefix string, security securityMode) (urlStr string, imports []metaImport, err error) {
+func metaImportsForPrefix(importPrefix string, security web.SecurityMode) (urlStr string, imports []metaImport, err error) {
 	setCache := func(res fetchResult) (fetchResult, error) {
 		fetchCacheMu.Lock()
 		defer fetchCacheMu.Unlock()
@@ -757,7 +756,7 @@
 		}
 		fetchCacheMu.Unlock()
 
-		urlStr, body, err := httpsOrHTTP(importPrefix, security)
+		urlStr, body, err := web.GetMaybeInsecure(importPrefix, security)
 		if err != nil {
 			return setCache(fetchResult{urlStr: urlStr, err: fmt.Errorf("fetch %s: %v", urlStr, err)})
 		}
@@ -857,7 +856,7 @@
 	// Github
 	{
 		prefix: "github.com/",
-		re:     `^(?P<root>github\.com/[A-Za-z0-9_.\-]+/[A-Za-z0-9_.\-]+)(/[A-Za-z0-9_.\-]+)*$`,
+		re:     `^(?P<root>github\.com/[A-Za-z0-9_.\-]+/[A-Za-z0-9_.\-]+)(/[\p{L}0-9_.\-]+)*$`,
 		vcs:    "git",
 		repo:   "https://{root}",
 		check:  noVCSSuffix,
@@ -954,10 +953,10 @@
 	var resp struct {
 		SCM string `json:"scm"`
 	}
-	url := expand(match, "https://api.bitbucket.org/1.0/repositories/{bitname}")
-	data, err := httpGET(url)
+	url := expand(match, "https://api.bitbucket.org/2.0/repositories/{bitname}?fields=scm")
+	data, err := web.Get(url)
 	if err != nil {
-		if httpErr, ok := err.(*httpError); ok && httpErr.statusCode == 403 {
+		if httpErr, ok := err.(*web.HTTPError); ok && httpErr.StatusCode == 403 {
 			// this may be a private repository. If so, attempt to determine which
 			// VCS it uses. See issue 5375.
 			root := match["root"]
@@ -997,7 +996,7 @@
 	if match["project"] == "" || match["series"] == "" {
 		return nil
 	}
-	_, err := httpGET(expand(match, "https://code.launchpad.net/{project}{series}/.bzr/branch-format"))
+	_, err := web.Get(expand(match, "https://code.launchpad.net/{project}{series}/.bzr/branch-format"))
 	if err != nil {
 		match["root"] = expand(match, "launchpad.net/{project}")
 		match["repo"] = expand(match, "https://{root}")
diff --git a/libgo/go/cmd/go/vcs_test.go b/libgo/go/cmd/go/internal/get/vcs_test.go
similarity index 94%
rename from libgo/go/cmd/go/vcs_test.go
rename to libgo/go/cmd/go/internal/get/vcs_test.go
index c73f5d0..62d352a 100644
--- a/libgo/go/cmd/go/vcs_test.go
+++ b/libgo/go/cmd/go/internal/get/vcs_test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package get
 
 import (
 	"errors"
@@ -12,6 +12,8 @@
 	"path"
 	"path/filepath"
 	"testing"
+
+	"cmd/go/internal/web"
 )
 
 // Test that RepoRootForImportPath creates the correct RepoRoot for a given importPath.
@@ -30,6 +32,14 @@
 				repo: "https://github.com/golang/groupcache",
 			},
 		},
+		// Unicode letters in directories (issue 18660).
+		{
+			"github.com/user/unicode/испытание",
+			&repoRoot{
+				vcs:  vcsGit,
+				repo: "https://github.com/user/unicode",
+			},
+		},
 		// IBM DevOps Services tests
 		{
 			"hub.jazz.net/git/user1/pkgname",
@@ -147,21 +157,21 @@
 	}
 
 	for _, test := range tests {
-		got, err := repoRootForImportPath(test.path, secure)
+		got, err := repoRootForImportPath(test.path, web.Secure)
 		want := test.want
 
 		if want == nil {
 			if err == nil {
-				t.Errorf("RepoRootForImport(%q): Error expected but not received", test.path)
+				t.Errorf("repoRootForImportPath(%q): Error expected but not received", test.path)
 			}
 			continue
 		}
 		if err != nil {
-			t.Errorf("RepoRootForImport(%q): %v", test.path, err)
+			t.Errorf("repoRootForImportPath(%q): %v", test.path, err)
 			continue
 		}
 		if got.vcs.name != want.vcs.name || got.repo != want.repo {
-			t.Errorf("RepoRootForImport(%q) = VCS(%s) Repo(%s), want VCS(%s) Repo(%s)", test.path, got.vcs, got.repo, want.vcs, want.repo)
+			t.Errorf("repoRootForImportPath(%q) = VCS(%s) Repo(%s), want VCS(%s) Repo(%s)", test.path, got.vcs, got.repo, want.vcs, want.repo)
 		}
 	}
 }
diff --git a/libgo/go/cmd/go/internal/help/help.go b/libgo/go/cmd/go/internal/help/help.go
new file mode 100644
index 0000000..b4c5217
--- /dev/null
+++ b/libgo/go/cmd/go/internal/help/help.go
@@ -0,0 +1,178 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package help implements the ``go help'' command.
+package help
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+	"text/template"
+	"unicode"
+	"unicode/utf8"
+
+	"cmd/go/internal/base"
+)
+
+// Help implements the 'help' command.
+func Help(args []string) {
+	if len(args) == 0 {
+		PrintUsage(os.Stdout)
+		// not exit 2: succeeded at 'go help'.
+		return
+	}
+	if len(args) != 1 {
+		fmt.Fprintf(os.Stderr, "usage: go help command\n\nToo many arguments given.\n")
+		os.Exit(2) // failed at 'go help'
+	}
+
+	arg := args[0]
+
+	// 'go help documentation' generates doc.go.
+	if arg == "documentation" {
+		fmt.Println("// Copyright 2011 The Go Authors. All rights reserved.")
+		fmt.Println("// Use of this source code is governed by a BSD-style")
+		fmt.Println("// license that can be found in the LICENSE file.")
+		fmt.Println()
+		fmt.Println("// DO NOT EDIT THIS FILE. GENERATED BY mkalldocs.sh.")
+		fmt.Println("// Edit the documentation in other files and rerun mkalldocs.sh to generate this one.")
+		fmt.Println()
+		buf := new(bytes.Buffer)
+		PrintUsage(buf)
+		usage := &base.Command{Long: buf.String()}
+		tmpl(&commentWriter{W: os.Stdout}, documentationTemplate, append([]*base.Command{usage}, base.Commands...))
+		fmt.Println("package main")
+		return
+	}
+
+	for _, cmd := range base.Commands {
+		if cmd.Name() == arg {
+			tmpl(os.Stdout, helpTemplate, cmd)
+			// not exit 2: succeeded at 'go help cmd'.
+			return
+		}
+	}
+
+	fmt.Fprintf(os.Stderr, "Unknown help topic %#q. Run 'go help'.\n", arg)
+	os.Exit(2) // failed at 'go help cmd'
+}
+
+var usageTemplate = `Go is a tool for managing Go source code.
+
+Usage:
+
+	go command [arguments]
+
+The commands are:
+{{range .}}{{if .Runnable}}
+	{{.Name | printf "%-11s"}} {{.Short}}{{end}}{{end}}
+
+Use "go help [command]" for more information about a command.
+
+Additional help topics:
+{{range .}}{{if not .Runnable}}
+	{{.Name | printf "%-11s"}} {{.Short}}{{end}}{{end}}
+
+Use "go help [topic]" for more information about that topic.
+
+`
+
+var helpTemplate = `{{if .Runnable}}usage: go {{.UsageLine}}
+
+{{end}}{{.Long | trim}}
+`
+
+var documentationTemplate = `{{range .}}{{if .Short}}{{.Short | capitalize}}
+
+{{end}}{{if .Runnable}}Usage:
+
+	go {{.UsageLine}}
+
+{{end}}{{.Long | trim}}
+
+
+{{end}}`
+
+// commentWriter writes a Go comment to the underlying io.Writer,
+// using line comment form (//).
+type commentWriter struct {
+	W            io.Writer
+	wroteSlashes bool // Wrote "//" at the beginning of the current line.
+}
+
+func (c *commentWriter) Write(p []byte) (int, error) {
+	var n int
+	for i, b := range p {
+		if !c.wroteSlashes {
+			s := "//"
+			if b != '\n' {
+				s = "// "
+			}
+			if _, err := io.WriteString(c.W, s); err != nil {
+				return n, err
+			}
+			c.wroteSlashes = true
+		}
+		n0, err := c.W.Write(p[i : i+1])
+		n += n0
+		if err != nil {
+			return n, err
+		}
+		if b == '\n' {
+			c.wroteSlashes = false
+		}
+	}
+	return len(p), nil
+}
+
+// An errWriter wraps a writer, recording whether a write error occurred.
+type errWriter struct {
+	w   io.Writer
+	err error
+}
+
+func (w *errWriter) Write(b []byte) (int, error) {
+	n, err := w.w.Write(b)
+	if err != nil {
+		w.err = err
+	}
+	return n, err
+}
+
+// tmpl executes the given template text on data, writing the result to w.
+func tmpl(w io.Writer, text string, data interface{}) {
+	t := template.New("top")
+	t.Funcs(template.FuncMap{"trim": strings.TrimSpace, "capitalize": capitalize})
+	template.Must(t.Parse(text))
+	ew := &errWriter{w: w}
+	err := t.Execute(ew, data)
+	if ew.err != nil {
+		// I/O error writing. Ignore write on closed pipe.
+		if strings.Contains(ew.err.Error(), "pipe") {
+			os.Exit(1)
+		}
+		base.Fatalf("writing output: %v", ew.err)
+	}
+	if err != nil {
+		panic(err)
+	}
+}
+
+func capitalize(s string) string {
+	if s == "" {
+		return s
+	}
+	r, n := utf8.DecodeRuneInString(s)
+	return string(unicode.ToTitle(r)) + s[n:]
+}
+
+func PrintUsage(w io.Writer) {
+	bw := bufio.NewWriter(w)
+	tmpl(bw, usageTemplate, base.Commands)
+	bw.Flush()
+}
diff --git a/libgo/go/cmd/go/help.go b/libgo/go/cmd/go/internal/help/helpdoc.go
similarity index 89%
rename from libgo/go/cmd/go/help.go
rename to libgo/go/cmd/go/internal/help/helpdoc.go
index 6b7422c..516fff3 100644
--- a/libgo/go/cmd/go/help.go
+++ b/libgo/go/cmd/go/internal/help/helpdoc.go
@@ -2,31 +2,33 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package help
 
-var helpC = &Command{
+import "cmd/go/internal/base"
+
+var HelpC = &base.Command{
 	UsageLine: "c",
 	Short:     "calling between Go and C",
 	Long: `
 There are two different ways to call between Go and C/C++ code.
 
-The first is the cgo tool, which is part of the Go distribution.  For
+The first is the cgo tool, which is part of the Go distribution. For
 information on how to use it see the cgo documentation (go doc cmd/cgo).
 
 The second is the SWIG program, which is a general tool for
-interfacing between languages.  For information on SWIG see
-http://swig.org/.  When running go build, any file with a .swig
-extension will be passed to SWIG.  Any file with a .swigcxx extension
+interfacing between languages. For information on SWIG see
+http://swig.org/. When running go build, any file with a .swig
+extension will be passed to SWIG. Any file with a .swigcxx extension
 will be passed to SWIG with the -c++ option.
 
 When either cgo or SWIG is used, go build will pass any .c, .m, .s,
 or .S files to the C compiler, and any .cc, .cpp, .cxx files to the C++
-compiler.  The CC or CXX environment variables may be set to determine
+compiler. The CC or CXX environment variables may be set to determine
 the C or C++ compiler, respectively, to use.
 	`,
 }
 
-var helpPackages = &Command{
+var HelpPackages = &base.Command{
 	UsageLine: "packages",
 	Short:     "description of package lists",
 	Long: `
@@ -67,17 +69,28 @@
 
 An import path is a pattern if it includes one or more "..." wildcards,
 each of which can match any string, including the empty string and
-strings containing slashes.  Such a pattern expands to all package
+strings containing slashes. Such a pattern expands to all package
 directories found in the GOPATH trees with names matching the
-patterns.  As a special case, x/... matches x as well as x's subdirectories.
-For example, net/... expands to net and packages in its subdirectories.
+patterns.
+
+To make common patterns more convenient, there are two special cases.
+First, /... at the end of the pattern can match an empty string,
+so that net/... matches both net and packages in its subdirectories, like net/http.
+Second, any slash-separated pattern element containing a wildcard never
+participates in a match of the "vendor" element in the path of a vendored
+package, so that ./... does not match packages in subdirectories of
+./vendor or ./mycode/vendor, but ./vendor/... and ./mycode/vendor/... do.
+Note, however, that a directory named vendor that itself contains code
+is not a vendored package: cmd/vendor would be a command named vendor,
+and the pattern cmd/... matches it.
+See golang.org/s/go15vendor for more about vendoring.
 
 An import path can also name a package to be downloaded from
-a remote repository.  Run 'go help importpath' for details.
+a remote repository. Run 'go help importpath' for details.
 
 Every package in a program must have a unique import path.
 By convention, this is arranged by starting each path with a
-unique prefix that belongs to you.  For example, paths used
+unique prefix that belongs to you. For example, paths used
 internally at Google all begin with 'google', and paths
 denoting remote repositories begin with the path to the code,
 such as 'github.com/user/repo'.
@@ -100,13 +113,13 @@
 	`,
 }
 
-var helpImportPath = &Command{
+var HelpImportPath = &base.Command{
 	UsageLine: "importpath",
 	Short:     "import path syntax",
 	Long: `
 
 An import path (see 'go help packages') denotes a package stored in the local
-file system.  In general, an import path denotes either a standard package (such
+file system. In general, an import path denotes either a standard package (such
 as "unicode/utf8") or a package found in one of the work spaces (For more
 details see: 'go help gopath').
 
@@ -177,7 +190,7 @@
 
 specifies the given repository, with or without the .vcs suffix,
 using the named version control system, and then the path inside
-that repository.  The supported version control systems are:
+that repository. The supported version control systems are:
 
 	Bazaar      .bzr
 	Git         .git
@@ -197,7 +210,7 @@
 example.org/repo or repo.git.
 
 When a version control system supports multiple protocols,
-each is tried in turn when downloading.  For example, a Git
+each is tried in turn when downloading. For example, a Git
 download tries https://, then git+ssh://.
 
 By default, downloads are restricted to known secure protocols
@@ -277,7 +290,7 @@
 	`,
 }
 
-var helpGopath = &Command{
+var HelpGopath = &base.Command{
 	UsageLine: "gopath",
 	Short:     "GOPATH environment variable",
 	Long: `
@@ -299,7 +312,7 @@
 
 Each directory listed in GOPATH must have a prescribed structure:
 
-The src directory holds source code.  The path below src
+The src directory holds source code. The path below src
 determines the import path or executable name.
 
 The pkg directory holds installed package objects.
@@ -313,11 +326,11 @@
 
 The bin directory holds compiled commands.
 Each command is named for its source directory, but only
-the final element, not the entire path.  That is, the
+the final element, not the entire path. That is, the
 command with source in DIR/src/foo/quux is installed into
-DIR/bin/quux, not DIR/bin/foo/quux.  The "foo/" prefix is stripped
+DIR/bin/quux, not DIR/bin/foo/quux. The "foo/" prefix is stripped
 so that you can add DIR/bin to your PATH to get at the
-installed commands.  If the GOBIN environment variable is
+installed commands. If the GOBIN environment variable is
 set, commands are installed to the directory it names instead
 of DIR/bin. GOBIN must be an absolute path.
 
@@ -429,7 +442,7 @@
 	`,
 }
 
-var helpEnvironment = &Command{
+var HelpEnvironment = &base.Command{
 	UsageLine: "environment",
 	Short:     "environment variables",
 	Long: `
@@ -464,7 +477,7 @@
 	CC
 		The command to use to compile C code.
 	CGO_ENABLED
-		Whether the cgo command is supported.  Either 0 or 1.
+		Whether the cgo command is supported. Either 0 or 1.
 	CGO_CFLAGS
 		Flags that cgo will pass to the compiler when compiling
 		C code.
@@ -514,7 +527,7 @@
 	`,
 }
 
-var helpFileType = &Command{
+var HelpFileType = &base.Command{
 	UsageLine: "filetype",
 	Short:     "file types",
 	Long: `
@@ -560,7 +573,7 @@
 	`,
 }
 
-var helpBuildmode = &Command{
+var HelpBuildmode = &base.Command{
 	UsageLine: "buildmode",
 	Short:     "description of build modes",
 	Long: `
@@ -579,10 +592,10 @@
 		exactly one main package to be listed.
 
 	-buildmode=c-shared
-		Build the listed main packages, plus all packages that they
-		import, into C shared libraries. The only callable symbols will
+		Build the listed main package, plus all packages it imports,
+		into a C shared library. The only callable symbols will
 		be those functions exported using a cgo //export comment.
-		Non-main packages are ignored.
+		Requires exactly one main package to be listed.
 
 	-buildmode=default
 		Listed main packages are built into executables and listed
diff --git a/libgo/go/cmd/go/context.go b/libgo/go/cmd/go/internal/list/context.go
similarity index 98%
rename from libgo/go/cmd/go/context.go
rename to libgo/go/cmd/go/internal/list/context.go
index 94cd54d..68d691e 100644
--- a/libgo/go/cmd/go/context.go
+++ b/libgo/go/cmd/go/internal/list/context.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package list
 
 import (
 	"go/build"
diff --git a/libgo/go/cmd/go/list.go b/libgo/go/cmd/go/internal/list/list.go
similarity index 85%
rename from libgo/go/cmd/go/list.go
rename to libgo/go/cmd/go/internal/list/list.go
index 2f24083..241d089 100644
--- a/libgo/go/cmd/go/list.go
+++ b/libgo/go/cmd/go/internal/list/list.go
@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package list implements the ``go list'' command.
+package list
 
 import (
 	"bufio"
@@ -11,9 +12,14 @@
 	"os"
 	"strings"
 	"text/template"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/work"
 )
 
-var cmdList = &Command{
+var CmdList = &base.Command{
 	UsageLine: "list [-e] [-f format] [-json] [build flags] [packages]",
 	Short:     "list packages",
 	Long: `
@@ -27,7 +33,7 @@
     golang.org/x/net/html
 
 The -f flag specifies an alternate format for the list, using the
-syntax of package template.  The default output is equivalent to -f
+syntax of package template. The default output is equivalent to -f
 '{{.ImportPath}}'. The struct being passed to the template is:
 
     type Package struct {
@@ -120,12 +126,12 @@
 instead of using the template format.
 
 The -e flag changes the handling of erroneous packages, those that
-cannot be found or are malformed.  By default, the list command
+cannot be found or are malformed. By default, the list command
 prints an error to standard error for each erroneous package and
 omits the packages from consideration during the usual printing.
 With the -e flag, the list command never prints errors to standard
 error and instead processes the erroneous packages with the usual
-printing.  Erroneous packages will have a non-empty ImportPath and
+printing. Erroneous packages will have a non-empty ImportPath and
 a non-nil Error field; other information may or may not be missing
 (zeroed).
 
@@ -136,27 +142,27 @@
 }
 
 func init() {
-	cmdList.Run = runList // break init cycle
-	addBuildFlags(cmdList)
+	CmdList.Run = runList // break init cycle
+	work.AddBuildFlags(CmdList)
 }
 
-var listE = cmdList.Flag.Bool("e", false, "")
-var listFmt = cmdList.Flag.String("f", "{{.ImportPath}}", "")
-var listJson = cmdList.Flag.Bool("json", false, "")
+var listE = CmdList.Flag.Bool("e", false, "")
+var listFmt = CmdList.Flag.String("f", "{{.ImportPath}}", "")
+var listJson = CmdList.Flag.Bool("json", false, "")
 var nl = []byte{'\n'}
 
-func runList(cmd *Command, args []string) {
-	buildModeInit()
+func runList(cmd *base.Command, args []string) {
+	work.BuildModeInit()
 	out := newTrackingWriter(os.Stdout)
 	defer out.w.Flush()
 
-	var do func(*Package)
+	var do func(*load.PackagePublic)
 	if *listJson {
-		do = func(p *Package) {
+		do = func(p *load.PackagePublic) {
 			b, err := json.MarshalIndent(p, "", "\t")
 			if err != nil {
 				out.Flush()
-				fatalf("%s", err)
+				base.Fatalf("%s", err)
 			}
 			out.Write(b)
 			out.Write(nl)
@@ -165,7 +171,7 @@
 		var cachedCtxt *Context
 		context := func() *Context {
 			if cachedCtxt == nil {
-				cachedCtxt = newContext(&buildContext)
+				cachedCtxt = newContext(&cfg.BuildContext)
 			}
 			return cachedCtxt
 		}
@@ -175,12 +181,12 @@
 		}
 		tmpl, err := template.New("main").Funcs(fm).Parse(*listFmt)
 		if err != nil {
-			fatalf("%s", err)
+			base.Fatalf("%s", err)
 		}
-		do = func(p *Package) {
+		do = func(p *load.PackagePublic) {
 			if err := tmpl.Execute(out, p); err != nil {
 				out.Flush()
-				fatalf("%s", err)
+				base.Fatalf("%s", err)
 			}
 			if out.NeedNL() {
 				out.Write(nl)
@@ -188,17 +194,17 @@
 		}
 	}
 
-	load := packages
+	loadpkgs := load.Packages
 	if *listE {
-		load = packagesAndErrors
+		loadpkgs = load.PackagesAndErrors
 	}
 
-	for _, pkg := range load(args) {
+	for _, pkg := range loadpkgs(args) {
 		// Show vendor-expanded paths in listing
-		pkg.TestImports = pkg.vendored(pkg.TestImports)
-		pkg.XTestImports = pkg.vendored(pkg.XTestImports)
+		pkg.TestImports = pkg.Vendored(pkg.TestImports)
+		pkg.XTestImports = pkg.Vendored(pkg.XTestImports)
 
-		do(pkg)
+		do(&pkg.PackagePublic)
 	}
 }
 
diff --git a/libgo/go/cmd/go/internal/load/match_test.go b/libgo/go/cmd/go/internal/load/match_test.go
new file mode 100644
index 0000000..b8d67da
--- /dev/null
+++ b/libgo/go/cmd/go/internal/load/match_test.go
@@ -0,0 +1,165 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package load
+
+import (
+	"strings"
+	"testing"
+)
+
+var matchPatternTests = `
+	pattern ...
+	match foo
+	
+	pattern net
+	match net
+	not net/http
+	
+	pattern net/http
+	match net/http
+	not net
+	
+	pattern net...
+	match net net/http netchan
+	not not/http not/net/http
+	
+	# Special cases. Quoting docs:
+
+	# First, /... at the end of the pattern can match an empty string,
+	# so that net/... matches both net and packages in its subdirectories, like net/http.
+	pattern net/...
+	match net net/http
+	not not/http not/net/http netchan
+
+	# Second, any slash-separted pattern element containing a wildcard never
+	# participates in a match of the "vendor" element in the path of a vendored
+	# package, so that ./... does not match packages in subdirectories of
+	# ./vendor or ./mycode/vendor, but ./vendor/... and ./mycode/vendor/... do.
+	# Note, however, that a directory named vendor that itself contains code
+	# is not a vendored package: cmd/vendor would be a command named vendor,
+	# and the pattern cmd/... matches it.
+	pattern ./...
+	match ./vendor ./mycode/vendor
+	not ./vendor/foo ./mycode/vendor/foo
+	
+	pattern ./vendor/...
+	match ./vendor/foo ./vendor/foo/vendor
+	not ./vendor/foo/vendor/bar
+	
+	pattern mycode/vendor/...
+	match mycode/vendor mycode/vendor/foo mycode/vendor/foo/vendor
+	not mycode/vendor/foo/vendor/bar
+	
+	pattern x/vendor/y
+	match x/vendor/y
+	not x/vendor
+	
+	pattern x/vendor/y/...
+	match x/vendor/y x/vendor/y/z x/vendor/y/vendor x/vendor/y/z/vendor
+	not x/vendor/y/vendor/z
+	
+	pattern .../vendor/...
+	match x/vendor/y x/vendor/y/z x/vendor/y/vendor x/vendor/y/z/vendor
+`
+
+func TestMatchPattern(t *testing.T) {
+	testPatterns(t, "matchPattern", matchPatternTests, func(pattern, name string) bool {
+		return matchPattern(pattern)(name)
+	})
+}
+
+var treeCanMatchPatternTests = `
+	pattern ...
+	match foo
+	
+	pattern net
+	match net
+	not net/http
+	
+	pattern net/http
+	match net net/http
+	
+	pattern net...
+	match net netchan net/http
+	not not/http not/net/http
+
+	pattern net/...
+	match net net/http
+	not not/http netchan
+	
+	pattern abc.../def
+	match abcxyz
+	not xyzabc
+	
+	pattern x/y/z/...
+	match x x/y x/y/z x/y/z/w
+	
+	pattern x/y/z
+	match x x/y x/y/z
+	not x/y/z/w
+	
+	pattern x/.../y/z
+	match x/a/b/c
+	not y/x/a/b/c
+`
+
+func TestTreeCanMatchPattern(t *testing.T) {
+	testPatterns(t, "treeCanMatchPattern", treeCanMatchPatternTests, func(pattern, name string) bool {
+		return treeCanMatchPattern(pattern)(name)
+	})
+}
+
+var hasPathPrefixTests = []stringPairTest{
+	{"abc", "a", false},
+	{"a/bc", "a", true},
+	{"a", "a", true},
+	{"a/bc", "a/", true},
+}
+
+func TestHasPathPrefix(t *testing.T) {
+	testStringPairs(t, "hasPathPrefix", hasPathPrefixTests, hasPathPrefix)
+}
+
+type stringPairTest struct {
+	in1 string
+	in2 string
+	out bool
+}
+
+func testStringPairs(t *testing.T, name string, tests []stringPairTest, f func(string, string) bool) {
+	for _, tt := range tests {
+		if out := f(tt.in1, tt.in2); out != tt.out {
+			t.Errorf("%s(%q, %q) = %v, want %v", name, tt.in1, tt.in2, out, tt.out)
+		}
+	}
+}
+
+func testPatterns(t *testing.T, name, tests string, fn func(string, string) bool) {
+	var patterns []string
+	for _, line := range strings.Split(tests, "\n") {
+		if i := strings.Index(line, "#"); i >= 0 {
+			line = line[:i]
+		}
+		f := strings.Fields(line)
+		if len(f) == 0 {
+			continue
+		}
+		switch f[0] {
+		default:
+			t.Fatalf("unknown directive %q", f[0])
+		case "pattern":
+			patterns = f[1:]
+		case "match", "not":
+			want := f[0] == "match"
+			for _, pattern := range patterns {
+				for _, in := range f[1:] {
+					if fn(pattern, in) != want {
+						t.Errorf("%s(%q, %q) = %v, want %v", name, pattern, in, !want, want)
+					}
+				}
+			}
+		}
+	}
+}
diff --git a/libgo/go/cmd/go/internal/load/path.go b/libgo/go/cmd/go/internal/load/path.go
new file mode 100644
index 0000000..9cc85dd
--- /dev/null
+++ b/libgo/go/cmd/go/internal/load/path.go
@@ -0,0 +1,80 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package load
+
+import (
+	"path/filepath"
+	"strings"
+)
+
+// hasSubdir reports whether dir is a subdirectory of
+// (possibly multiple levels below) root.
+// If so, it sets rel to the path fragment that must be
+// appended to root to reach dir.
+func hasSubdir(root, dir string) (rel string, ok bool) {
+	if p, err := filepath.EvalSymlinks(root); err == nil {
+		root = p
+	}
+	if p, err := filepath.EvalSymlinks(dir); err == nil {
+		dir = p
+	}
+	const sep = string(filepath.Separator)
+	root = filepath.Clean(root)
+	if !strings.HasSuffix(root, sep) {
+		root += sep
+	}
+	dir = filepath.Clean(dir)
+	if !strings.HasPrefix(dir, root) {
+		return "", false
+	}
+	return filepath.ToSlash(dir[len(root):]), true
+}
+
+// hasPathPrefix reports whether the path s begins with the
+// elements in prefix.
+func hasPathPrefix(s, prefix string) bool {
+	switch {
+	default:
+		return false
+	case len(s) == len(prefix):
+		return s == prefix
+	case len(s) > len(prefix):
+		if prefix != "" && prefix[len(prefix)-1] == '/' {
+			return strings.HasPrefix(s, prefix)
+		}
+		return s[len(prefix)] == '/' && s[:len(prefix)] == prefix
+	}
+}
+
+// expandPath returns the symlink-expanded form of path.
+func expandPath(p string) string {
+	x, err := filepath.EvalSymlinks(p)
+	if err == nil {
+		return x
+	}
+	return p
+}
+
+// hasFilePathPrefix reports whether the filesystem path s begins with the
+// elements in prefix.
+func hasFilePathPrefix(s, prefix string) bool {
+	sv := strings.ToUpper(filepath.VolumeName(s))
+	pv := strings.ToUpper(filepath.VolumeName(prefix))
+	s = s[len(sv):]
+	prefix = prefix[len(pv):]
+	switch {
+	default:
+		return false
+	case sv != pv:
+		return false
+	case len(s) == len(prefix):
+		return s == prefix
+	case len(s) > len(prefix):
+		if prefix != "" && prefix[len(prefix)-1] == filepath.Separator {
+			return strings.HasPrefix(s, prefix)
+		}
+		return s[len(prefix)] == filepath.Separator && s[:len(prefix)] == prefix
+	}
+}
diff --git a/libgo/go/cmd/go/pkg.go b/libgo/go/cmd/go/internal/load/pkg.go
similarity index 75%
rename from libgo/go/cmd/go/pkg.go
rename to libgo/go/cmd/go/internal/load/pkg.go
index f0dc956..acb20fe 100644
--- a/libgo/go/cmd/go/pkg.go
+++ b/libgo/go/cmd/go/internal/load/pkg.go
@@ -2,32 +2,38 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package load loads packages.
+package load
 
 import (
-	"bytes"
 	"crypto/sha1"
-	"errors"
 	"fmt"
 	"go/build"
-	"go/scanner"
 	"go/token"
-	"io"
 	"io/ioutil"
 	"os"
 	pathpkg "path"
 	"path/filepath"
 	"runtime"
 	"sort"
-	"strconv"
 	"strings"
 	"unicode"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/buildid"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/str"
 )
 
-var ignoreImports bool // control whether we ignore imports in packages
+var IgnoreImports bool // control whether we ignore imports in packages
 
 // A Package describes a single package found in a directory.
 type Package struct {
+	PackagePublic                 // visible in 'go list'
+	Internal      PackageInternal // for use inside go command only
+}
+
+type PackagePublic struct {
 	// Note: These fields are part of the go command's public API.
 	// See list.go. It is okay to add fields, but not to change or
 	// remove existing ones. Keep in sync with list.go
@@ -82,31 +88,59 @@
 	TestImports  []string `json:",omitempty"` // imports from TestGoFiles
 	XTestGoFiles []string `json:",omitempty"` // _test.go files outside package
 	XTestImports []string `json:",omitempty"` // imports from XTestGoFiles
-
-	// Unexported fields are not part of the public API.
-	build        *build.Package
-	pkgdir       string // overrides build.PkgDir
-	imports      []*Package
-	deps         []*Package
-	gofiles      []string // GoFiles+CgoFiles+TestGoFiles+XTestGoFiles files, absolute paths
-	sfiles       []string
-	allgofiles   []string             // gofiles + IgnoredGoFiles, absolute paths
-	target       string               // installed file for this package (may be executable)
-	fake         bool                 // synthesized package
-	external     bool                 // synthesized external test package
-	forceLibrary bool                 // this package is a library (even if named "main")
-	cmdline      bool                 // defined by files listed on command line
-	local        bool                 // imported via local path (./ or ../)
-	localPrefix  string               // interpret ./ and ../ imports relative to this prefix
-	exeName      string               // desired name for temporary executable
-	coverMode    string               // preprocess Go source files with the coverage tool in this mode
-	coverVars    map[string]*CoverVar // variables created by coverage analysis
-	omitDWARF    bool                 // tell linker not to write DWARF information
-	buildID      string               // expected build ID for generated package
-	gobinSubdir  bool                 // install target would be subdir of GOBIN
 }
 
-// vendored returns the vendor-resolved version of imports,
+type PackageInternal struct {
+	// Unexported fields are not part of the public API.
+	Build        *build.Package
+	Pkgdir       string // overrides build.PkgDir
+	Imports      []*Package
+	Deps         []*Package
+	GoFiles      []string // GoFiles+CgoFiles+TestGoFiles+XTestGoFiles files, absolute paths
+	SFiles       []string
+	AllGoFiles   []string             // gofiles + IgnoredGoFiles, absolute paths
+	Target       string               // installed file for this package (may be executable)
+	Fake         bool                 // synthesized package
+	External     bool                 // synthesized external test package
+	ForceLibrary bool                 // this package is a library (even if named "main")
+	Cmdline      bool                 // defined by files listed on command line
+	Local        bool                 // imported via local path (./ or ../)
+	LocalPrefix  string               // interpret ./ and ../ imports relative to this prefix
+	ExeName      string               // desired name for temporary executable
+	CoverMode    string               // preprocess Go source files with the coverage tool in this mode
+	CoverVars    map[string]*CoverVar // variables created by coverage analysis
+	OmitDebug    bool                 // tell linker not to write debug information
+	BuildID      string               // expected build ID for generated package
+	GobinSubdir  bool                 // install target would be subdir of GOBIN
+}
+
+type NoGoError struct {
+	Package *Package
+}
+
+func (e *NoGoError) Error() string {
+	// Count files beginning with _ and ., which we will pretend don't exist at all.
+	dummy := 0
+	for _, name := range e.Package.IgnoredGoFiles {
+		if strings.HasPrefix(name, "_") || strings.HasPrefix(name, ".") {
+			dummy++
+		}
+	}
+
+	if len(e.Package.IgnoredGoFiles) > dummy {
+		// Go files exist, but they were ignored due to build constraints.
+		return "build constraints exclude all Go files in " + e.Package.Dir
+	}
+	if len(e.Package.TestGoFiles)+len(e.Package.XTestGoFiles) > 0 {
+		// Test Go files exist, but we're not interested in them.
+		// The double-negative is unfortunate but we want e.Package.Dir
+		// to appear at the end of error message.
+		return "no non-test Go files in " + e.Package.Dir
+	}
+	return "no Go files in " + e.Package.Dir
+}
+
+// Vendored returns the vendor-resolved version of imports,
 // which should be p.TestImports or p.XTestImports, NOT p.Imports.
 // The imports in p.TestImports and p.XTestImports are not recursively
 // loaded during the initial load of p, so they list the imports found in
@@ -116,14 +150,14 @@
 // can produce better error messages if it starts with the original paths.
 // The initial load of p loads all the non-test imports and rewrites
 // the vendored paths, so nothing should ever call p.vendored(p.Imports).
-func (p *Package) vendored(imports []string) []string {
+func (p *Package) Vendored(imports []string) []string {
 	if len(imports) > 0 && len(p.Imports) > 0 && &imports[0] == &p.Imports[0] {
 		panic("internal error: p.vendored(p.Imports) called")
 	}
 	seen := make(map[string]bool)
 	var all []string
 	for _, path := range imports {
-		path = vendoredImportPath(p, path)
+		path = VendoredImportPath(p, path)
 		if !seen[path] {
 			seen[path] = true
 			all = append(all, path)
@@ -140,13 +174,13 @@
 }
 
 func (p *Package) copyBuild(pp *build.Package) {
-	p.build = pp
+	p.Internal.Build = pp
 
-	if pp.PkgTargetRoot != "" && buildPkgdir != "" {
+	if pp.PkgTargetRoot != "" && cfg.BuildPkgdir != "" {
 		old := pp.PkgTargetRoot
-		pp.PkgRoot = buildPkgdir
-		pp.PkgTargetRoot = buildPkgdir
-		pp.PkgObj = filepath.Join(buildPkgdir, strings.TrimPrefix(pp.PkgObj, old))
+		pp.PkgRoot = cfg.BuildPkgdir
+		pp.PkgTargetRoot = cfg.BuildPkgdir
+		pp.PkgObj = filepath.Join(cfg.BuildPkgdir, strings.TrimPrefix(pp.PkgObj, old))
 	}
 
 	p.Dir = pp.Dir
@@ -160,10 +194,9 @@
 
 	// TODO? Target
 	p.Goroot = pp.Goroot
-	if buildContext.Compiler == "gccgo" {
+	p.Standard = p.Goroot && p.ImportPath != "" && isStandardImportPath(p.ImportPath)
+	if cfg.BuildToolchainName == "gccgo" {
 		p.Standard = stdpkg[p.ImportPath]
-	} else {
-		p.Standard = p.Goroot && p.ImportPath != "" && isStandardImportPath(p.ImportPath)
 	}
 	p.GoFiles = pp.GoFiles
 	p.CgoFiles = pp.CgoFiles
@@ -180,6 +213,7 @@
 	p.CgoCFLAGS = pp.CgoCFLAGS
 	p.CgoCPPFLAGS = pp.CgoCPPFLAGS
 	p.CgoCXXFLAGS = pp.CgoCXXFLAGS
+	p.CgoFFLAGS = pp.CgoFFLAGS
 	p.CgoLDFLAGS = pp.CgoLDFLAGS
 	p.CgoPkgConfig = pp.CgoPkgConfig
 	// We modify p.Imports in place, so make copy now.
@@ -189,7 +223,7 @@
 	p.TestImports = pp.TestImports
 	p.XTestGoFiles = pp.XTestGoFiles
 	p.XTestImports = pp.XTestImports
-	if ignoreImports {
+	if IgnoreImports {
 		p.Imports = nil
 		p.TestImports = nil
 		p.XTestImports = nil
@@ -214,13 +248,13 @@
 	ImportStack   []string // shortest path from package named on command line to this one
 	Pos           string   // position of error
 	Err           string   // the error itself
-	isImportCycle bool     // the error is an import cycle
-	hard          bool     // whether the error is soft or hard; soft errors are ignored in some places
+	IsImportCycle bool     `json:"-"` // the error is an import cycle
+	Hard          bool     `json:"-"` // whether the error is soft or hard; soft errors are ignored in some places
 }
 
 func (p *PackageError) Error() string {
 	// Import cycles deserve special treatment.
-	if p.isImportCycle {
+	if p.IsImportCycle {
 		return fmt.Sprintf("%s\npackage %s\n", p.Err, strings.Join(p.ImportStack, "\n\timports "))
 	}
 	if p.Pos != "" {
@@ -234,25 +268,25 @@
 	return "package " + strings.Join(p.ImportStack, "\n\timports ") + ": " + p.Err
 }
 
-// An importStack is a stack of import paths.
-type importStack []string
+// An ImportStack is a stack of import paths.
+type ImportStack []string
 
-func (s *importStack) push(p string) {
+func (s *ImportStack) Push(p string) {
 	*s = append(*s, p)
 }
 
-func (s *importStack) pop() {
+func (s *ImportStack) Pop() {
 	*s = (*s)[0 : len(*s)-1]
 }
 
-func (s *importStack) copy() []string {
+func (s *ImportStack) Copy() []string {
 	return append([]string{}, *s...)
 }
 
 // shorterThan reports whether sp is shorter than t.
 // We use this to record the shortest import sequence
 // that leads to a particular package.
-func (sp *importStack) shorterThan(t []string) bool {
+func (sp *ImportStack) shorterThan(t []string) bool {
 	s := *sp
 	if len(s) != len(t) {
 		return len(s) < len(t)
@@ -271,15 +305,31 @@
 // we return the same pointer each time.
 var packageCache = map[string]*Package{}
 
+func ClearPackageCache() {
+	for name := range packageCache {
+		delete(packageCache, name)
+	}
+}
+
+func ClearPackageCachePartial(args []string) {
+	for _, arg := range args {
+		p := packageCache[arg]
+		if p != nil {
+			delete(packageCache, p.Dir)
+			delete(packageCache, p.ImportPath)
+		}
+	}
+}
+
 // reloadPackage is like loadPackage but makes sure
 // not to use the package cache.
-func reloadPackage(arg string, stk *importStack) *Package {
+func ReloadPackage(arg string, stk *ImportStack) *Package {
 	p := packageCache[arg]
 	if p != nil {
 		delete(packageCache, p.Dir)
 		delete(packageCache, p.ImportPath)
 	}
-	return loadPackage(arg, stk)
+	return LoadPackage(arg, stk)
 }
 
 // dirToImportPath returns the pseudo-import path we use for a package
@@ -313,20 +363,20 @@
 	// recorded as the canonical import path. At that point, future loads
 	// of that package must not pass useVendor, because
 	// disallowVendor will reject direct use of paths containing /vendor/.
-	useVendor = 1 << iota
+	UseVendor = 1 << iota
 
 	// getTestDeps is for download (part of "go get") and indicates
 	// that test dependencies should be fetched too.
-	getTestDeps
+	GetTestDeps
 )
 
 // loadImport scans the directory named by path, which must be an import path,
 // but possibly a local import path (an absolute file system path or one beginning
-// with ./ or ../).  A local relative path is interpreted relative to srcDir.
+// with ./ or ../). A local relative path is interpreted relative to srcDir.
 // It returns a *Package describing the package found in that directory.
-func loadImport(path, srcDir string, parent *Package, stk *importStack, importPos []token.Position, mode int) *Package {
-	stk.push(path)
-	defer stk.pop()
+func LoadImport(path, srcDir string, parent *Package, stk *ImportStack, importPos []token.Position, mode int) *Package {
+	stk.Push(path)
+	defer stk.Pop()
 
 	// Determine canonical identifier for this package.
 	// For a local import the identifier is the pseudo-import path
@@ -338,12 +388,12 @@
 	isLocal := build.IsLocalImport(path)
 	if isLocal {
 		importPath = dirToImportPath(filepath.Join(srcDir, path))
-	} else if mode&useVendor != 0 {
+	} else if mode&UseVendor != 0 {
 		// We do our own vendor resolution, because we want to
 		// find out the key to use in packageCache without the
 		// overhead of repeated calls to buildContext.Import.
 		// The code is also needed in a few other places anyway.
-		path = vendoredImportPath(parent, path)
+		path = VendoredImportPath(parent, path)
 		importPath = path
 	}
 
@@ -352,7 +402,7 @@
 		p = reusePackage(p, stk)
 	} else {
 		p = new(Package)
-		p.local = isLocal
+		p.Internal.Local = isLocal
 		p.ImportPath = importPath
 		packageCache[importPath] = p
 
@@ -363,14 +413,14 @@
 		// TODO: After Go 1, decide when to pass build.AllowBinary here.
 		// See issue 3268 for mistakes to avoid.
 		buildMode := build.ImportComment
-		if mode&useVendor == 0 || path != origPath {
+		if mode&UseVendor == 0 || path != origPath {
 			// Not vendoring, or we already found the vendored path.
 			buildMode |= build.IgnoreVendor
 		}
-		bp, err := buildContext.Import(path, srcDir, buildMode)
+		bp, err := cfg.BuildContext.Import(path, srcDir, buildMode)
 		bp.ImportPath = importPath
-		if gobin != "" {
-			bp.BinDir = gobin
+		if cfg.GOBIN != "" {
+			bp.BinDir = cfg.GOBIN
 		}
 		if err == nil && !isLocal && bp.ImportComment != "" && bp.ImportComment != path &&
 			!strings.Contains(path, "/vendor/") && !strings.HasPrefix(path, "vendor/") {
@@ -383,7 +433,7 @@
 
 		if origPath != cleanImport(origPath) {
 			p.Error = &PackageError{
-				ImportStack: stk.copy(),
+				ImportStack: stk.Copy(),
 				Err:         fmt.Sprintf("non-canonical import path: %q should be %q", origPath, pathpkg.Clean(origPath)),
 			}
 			p.Incomplete = true
@@ -394,7 +444,7 @@
 	if perr := disallowInternal(srcDir, p, stk); perr != p {
 		return setErrorPos(perr, importPos)
 	}
-	if mode&useVendor != 0 {
+	if mode&UseVendor != 0 {
 		if perr := disallowVendor(srcDir, origPath, p, stk); perr != p {
 			return setErrorPos(perr, importPos)
 		}
@@ -403,16 +453,16 @@
 	if p.Name == "main" && parent != nil && parent.Dir != p.Dir {
 		perr := *p
 		perr.Error = &PackageError{
-			ImportStack: stk.copy(),
+			ImportStack: stk.Copy(),
 			Err:         fmt.Sprintf("import %q is a program, not an importable package", path),
 		}
 		return setErrorPos(&perr, importPos)
 	}
 
-	if p.local && parent != nil && !parent.local {
+	if p.Internal.Local && parent != nil && !parent.Internal.Local {
 		perr := *p
 		perr.Error = &PackageError{
-			ImportStack: stk.copy(),
+			ImportStack: stk.Copy(),
 			Err:         fmt.Sprintf("local import %q in non-local package", path),
 		}
 		return setErrorPos(&perr, importPos)
@@ -424,7 +474,7 @@
 func setErrorPos(p *Package, importPos []token.Position) *Package {
 	if len(importPos) > 0 {
 		pos := importPos[0]
-		pos.Filename = shortPath(pos.Filename)
+		pos.Filename = base.ShortPath(pos.Filename)
 		p.Error.Pos = pos.String()
 	}
 	return p
@@ -453,11 +503,11 @@
 	return result
 }
 
-// vendoredImportPath returns the expansion of path when it appears in parent.
+// VendoredImportPath returns the expansion of path when it appears in parent.
 // If parent is x/y/z, then path might expand to x/y/z/vendor/path, x/y/vendor/path,
 // x/vendor/path, vendor/path, or else stay path if none of those exist.
-// vendoredImportPath returns the expanded path or, if no expansion is found, the original.
-func vendoredImportPath(parent *Package, path string) (found string) {
+// VendoredImportPath returns the expanded path or, if no expansion is found, the original.
+func VendoredImportPath(parent *Package, path string) (found string) {
 	if parent == nil || parent.Root == "" {
 		return path
 	}
@@ -470,8 +520,8 @@
 		root = expandPath(root)
 	}
 
-	if !hasFilePathPrefix(dir, root) || len(dir) <= len(root) || dir[len(root)] != filepath.Separator || parent.ImportPath != "command-line-arguments" && !parent.local && filepath.Join(root, parent.ImportPath) != dir {
-		fatalf("unexpected directory layout:\n"+
+	if !hasFilePathPrefix(dir, root) || len(dir) <= len(root) || dir[len(root)] != filepath.Separator || parent.ImportPath != "command-line-arguments" && !parent.Internal.Local && filepath.Join(root, parent.ImportPath) != dir {
+		base.Fatalf("unexpected directory layout:\n"+
 			"	import path: %s\n"+
 			"	root: %s\n"+
 			"	dir: %s\n"+
@@ -545,24 +595,24 @@
 // reusePackage reuses package p to satisfy the import at the top
 // of the import stack stk. If this use causes an import loop,
 // reusePackage updates p's error information to record the loop.
-func reusePackage(p *Package, stk *importStack) *Package {
-	// We use p.imports==nil to detect a package that
+func reusePackage(p *Package, stk *ImportStack) *Package {
+	// We use p.Internal.Imports==nil to detect a package that
 	// is in the midst of its own loadPackage call
-	// (all the recursion below happens before p.imports gets set).
-	if p.imports == nil {
+	// (all the recursion below happens before p.Internal.Imports gets set).
+	if p.Internal.Imports == nil {
 		if p.Error == nil {
 			p.Error = &PackageError{
-				ImportStack:   stk.copy(),
+				ImportStack:   stk.Copy(),
 				Err:           "import cycle not allowed",
-				isImportCycle: true,
+				IsImportCycle: true,
 			}
 		}
 		p.Incomplete = true
 	}
 	// Don't rewrite the import stack in the error if we have an import cycle.
 	// If we do, we'll lose the path that describes the cycle.
-	if p.Error != nil && !p.Error.isImportCycle && stk.shorterThan(p.Error.ImportStack) {
-		p.Error.ImportStack = stk.copy()
+	if p.Error != nil && !p.Error.IsImportCycle && stk.shorterThan(p.Error.ImportStack) {
+		p.Error.ImportStack = stk.Copy()
 	}
 	return p
 }
@@ -570,7 +620,7 @@
 // disallowInternal checks that srcDir is allowed to import p.
 // If the import is allowed, disallowInternal returns the original package p.
 // If not, it returns a new package containing just an appropriate error.
-func disallowInternal(srcDir string, p *Package, stk *importStack) *Package {
+func disallowInternal(srcDir string, p *Package, stk *ImportStack) *Package {
 	// golang.org/s/go14internal:
 	// An import of a path containing the element “internal”
 	// is disallowed if the importing code is outside the tree
@@ -590,7 +640,7 @@
 	}
 
 	// We can't check standard packages with gccgo.
-	if buildContext.Compiler == "gccgo" && p.Standard {
+	if cfg.BuildContext.Compiler == "gccgo" && p.Standard {
 		return p
 	}
 
@@ -628,7 +678,7 @@
 	// Internal is present, and srcDir is outside parent's tree. Not allowed.
 	perr := *p
 	perr.Error = &PackageError{
-		ImportStack: stk.copy(),
+		ImportStack: stk.Copy(),
 		Err:         "use of internal package not allowed",
 	}
 	perr.Incomplete = true
@@ -657,7 +707,7 @@
 // disallowVendor checks that srcDir is allowed to import p as path.
 // If the import is allowed, disallowVendor returns the original package p.
 // If not, it returns a new package containing just an appropriate error.
-func disallowVendor(srcDir, path string, p *Package, stk *importStack) *Package {
+func disallowVendor(srcDir, path string, p *Package, stk *ImportStack) *Package {
 	// The stack includes p.ImportPath.
 	// If that's the only thing on the stack, we started
 	// with a name given on the command line, not an
@@ -671,10 +721,10 @@
 	}
 
 	// Paths like x/vendor/y must be imported as y, never as x/vendor/y.
-	if i, ok := findVendor(path); ok {
+	if i, ok := FindVendor(path); ok {
 		perr := *p
 		perr.Error = &PackageError{
-			ImportStack: stk.copy(),
+			ImportStack: stk.Copy(),
 			Err:         "must be imported as " + path[i+len("vendor/"):],
 		}
 		perr.Incomplete = true
@@ -689,7 +739,7 @@
 // is not subject to the rules, only subdirectories of vendor.
 // This allows people to have packages and commands named vendor,
 // for maximal compatibility with existing source trees.
-func disallowVendorVisibility(srcDir string, p *Package, stk *importStack) *Package {
+func disallowVendorVisibility(srcDir string, p *Package, stk *ImportStack) *Package {
 	// The stack includes p.ImportPath.
 	// If that's the only thing on the stack, we started
 	// with a name given on the command line, not an
@@ -699,7 +749,7 @@
 	}
 
 	// Check for "vendor" element.
-	i, ok := findVendor(p.ImportPath)
+	i, ok := FindVendor(p.ImportPath)
 	if !ok {
 		return p
 	}
@@ -728,22 +778,22 @@
 	// Vendor is present, and srcDir is outside parent's tree. Not allowed.
 	perr := *p
 	perr.Error = &PackageError{
-		ImportStack: stk.copy(),
+		ImportStack: stk.Copy(),
 		Err:         "use of vendored package not allowed",
 	}
 	perr.Incomplete = true
 	return &perr
 }
 
-// findVendor looks for the last non-terminating "vendor" path element in the given import path.
-// If there isn't one, findVendor returns ok=false.
-// Otherwise, findVendor returns ok=true and the index of the "vendor".
+// FindVendor looks for the last non-terminating "vendor" path element in the given import path.
+// If there isn't one, FindVendor returns ok=false.
+// Otherwise, FindVendor returns ok=true and the index of the "vendor".
 //
 // Note that terminating "vendor" elements don't count: "x/vendor" is its own package,
 // not the vendored copy of an import "" (the empty import path).
 // This will allow people to have packages or commands named vendor.
 // This may help reduce breakage, or it may just be confusing. We'll see.
-func findVendor(path string) (index int, ok bool) {
+func FindVendor(path string) (index int, ok bool) {
 	// Two cases, depending on internal at start of string or not.
 	// The order matters: we must return the index of the final element,
 	// because the final one is where the effective import path starts.
@@ -759,54 +809,33 @@
 type targetDir int
 
 const (
-	toRoot    targetDir = iota // to bin dir inside package root (default)
-	toTool                     // GOROOT/pkg/tool
-	stalePath                  // the old import path; fail to build
+	ToRoot    targetDir = iota // to bin dir inside package root (default)
+	ToTool                     // GOROOT/pkg/tool
+	StalePath                  // the old import path; fail to build
 )
 
 // goTools is a map of Go program import path to install target directory.
-var goTools = map[string]targetDir{
-	"cmd/addr2line": toTool,
-	"cmd/api":       toTool,
-	"cmd/asm":       toTool,
-	"cmd/compile":   toTool,
-	"cmd/cgo":       toTool,
-	"cmd/cover":     toTool,
-	"cmd/dist":      toTool,
-	"cmd/doc":       toTool,
-	"cmd/fix":       toTool,
-	"cmd/link":      toTool,
-	"cmd/newlink":   toTool,
-	"cmd/nm":        toTool,
-	"cmd/objdump":   toTool,
-	"cmd/pack":      toTool,
-	"cmd/pprof":     toTool,
-	"cmd/trace":     toTool,
-	"cmd/vet":       toTool,
-	"code.google.com/p/go.tools/cmd/cover": stalePath,
-	"code.google.com/p/go.tools/cmd/godoc": stalePath,
-	"code.google.com/p/go.tools/cmd/vet":   stalePath,
-}
-
-// expandScanner expands a scanner.List error into all the errors in the list.
-// The default Error method only shows the first error.
-func expandScanner(err error) error {
-	// Look for parser errors.
-	if err, ok := err.(scanner.ErrorList); ok {
-		// Prepare error with \n before each message.
-		// When printed in something like context: %v
-		// this will put the leading file positions each on
-		// its own line. It will also show all the errors
-		// instead of just the first, as err.Error does.
-		var buf bytes.Buffer
-		for _, e := range err {
-			e.Pos.Filename = shortPath(e.Pos.Filename)
-			buf.WriteString("\n")
-			buf.WriteString(e.Error())
-		}
-		return errors.New(buf.String())
-	}
-	return err
+var GoTools = map[string]targetDir{
+	"cmd/addr2line": ToTool,
+	"cmd/api":       ToTool,
+	"cmd/asm":       ToTool,
+	"cmd/compile":   ToTool,
+	"cmd/cgo":       ToTool,
+	"cmd/cover":     ToTool,
+	"cmd/dist":      ToTool,
+	"cmd/doc":       ToTool,
+	"cmd/fix":       ToTool,
+	"cmd/link":      ToTool,
+	"cmd/newlink":   ToTool,
+	"cmd/nm":        ToTool,
+	"cmd/objdump":   ToTool,
+	"cmd/pack":      ToTool,
+	"cmd/pprof":     ToTool,
+	"cmd/trace":     ToTool,
+	"cmd/vet":       ToTool,
+	"code.google.com/p/go.tools/cmd/cover": StalePath,
+	"code.google.com/p/go.tools/cmd/godoc": StalePath,
+	"code.google.com/p/go.tools/cmd/vet":   StalePath,
 }
 
 var raceExclude = map[string]bool{
@@ -828,27 +857,32 @@
 	"runtime/msan": true,
 }
 
+var foldPath = make(map[string]string)
+
 // load populates p using information from bp, err, which should
 // be the result of calling build.Context.Import.
-func (p *Package) load(stk *importStack, bp *build.Package, err error) *Package {
+func (p *Package) load(stk *ImportStack, bp *build.Package, err error) *Package {
 	p.copyBuild(bp)
 
 	// When using gccgo the go/build package will not be able to
-	// find a standard package.  It would be nicer to not get that
+	// find a standard package. It would be nicer to not get that
 	// error, but go/build doesn't know stdpkg.
-	if runtime.Compiler == "gccgo" && err != nil && p.Standard {
+	if cfg.BuildToolchainName == "gccgo" && err != nil && p.Standard {
 		err = nil
 	}
 
 	// The localPrefix is the path we interpret ./ imports relative to.
 	// Synthesized main packages sometimes override this.
-	p.localPrefix = dirToImportPath(p.Dir)
+	p.Internal.LocalPrefix = dirToImportPath(p.Dir)
 
 	if err != nil {
+		if _, ok := err.(*build.NoGoError); ok {
+			err = &NoGoError{Package: p}
+		}
 		p.Incomplete = true
-		err = expandScanner(err)
+		err = base.ExpandScanner(err)
 		p.Error = &PackageError{
-			ImportStack: stk.copy(),
+			ImportStack: stk.Copy(),
 			Err:         err.Error(),
 		}
 		return p
@@ -856,7 +890,7 @@
 
 	useBindir := p.Name == "main"
 	if !p.Standard {
-		switch buildBuildmode {
+		switch cfg.BuildBuildmode {
 		case "c-archive", "c-shared", "plugin":
 			useBindir = false
 		}
@@ -864,111 +898,111 @@
 
 	if useBindir {
 		// Report an error when the old code.google.com/p/go.tools paths are used.
-		if goTools[p.ImportPath] == stalePath {
+		if GoTools[p.ImportPath] == StalePath {
 			newPath := strings.Replace(p.ImportPath, "code.google.com/p/go.", "golang.org/x/", 1)
 			e := fmt.Sprintf("the %v command has moved; use %v instead.", p.ImportPath, newPath)
 			p.Error = &PackageError{Err: e}
 			return p
 		}
 		_, elem := filepath.Split(p.Dir)
-		full := buildContext.GOOS + "_" + buildContext.GOARCH + "/" + elem
-		if buildContext.GOOS != toolGOOS || buildContext.GOARCH != toolGOARCH {
+		full := cfg.BuildContext.GOOS + "_" + cfg.BuildContext.GOARCH + "/" + elem
+		if cfg.BuildContext.GOOS != base.ToolGOOS || cfg.BuildContext.GOARCH != base.ToolGOARCH {
 			// Install cross-compiled binaries to subdirectories of bin.
 			elem = full
 		}
-		if p.build.BinDir != "" {
+		if p.Internal.Build.BinDir != "" {
 			// Install to GOBIN or bin of GOPATH entry.
-			p.target = filepath.Join(p.build.BinDir, elem)
-			if !p.Goroot && strings.Contains(elem, "/") && gobin != "" {
+			p.Internal.Target = filepath.Join(p.Internal.Build.BinDir, elem)
+			if !p.Goroot && strings.Contains(elem, "/") && cfg.GOBIN != "" {
 				// Do not create $GOBIN/goos_goarch/elem.
-				p.target = ""
-				p.gobinSubdir = true
+				p.Internal.Target = ""
+				p.Internal.GobinSubdir = true
 			}
 		}
-		if goTools[p.ImportPath] == toTool {
+		if GoTools[p.ImportPath] == ToTool {
 			// This is for 'go tool'.
 			// Override all the usual logic and force it into the tool directory.
-			if buildContext.Compiler == "gccgo" {
-				p.target = filepath.Join(runtime.GCCGOTOOLDIR, elem)
+			if cfg.BuildToolchainName == "gccgo" {
+				p.Internal.Target = filepath.Join(runtime.GCCGOTOOLDIR, elem)
 			} else {
-				p.target = filepath.Join(gorootPkg, "tool", full)
+				p.Internal.Target = filepath.Join(cfg.GOROOTpkg, "tool", full)
 			}
 		}
-		if p.target != "" && buildContext.GOOS == "windows" {
-			p.target += ".exe"
+		if p.Internal.Target != "" && cfg.BuildContext.GOOS == "windows" {
+			p.Internal.Target += ".exe"
 		}
-	} else if p.local {
+	} else if p.Internal.Local {
 		// Local import turned into absolute path.
 		// No permanent install target.
-		p.target = ""
+		p.Internal.Target = ""
 	} else {
-		p.target = p.build.PkgObj
-		if buildLinkshared {
-			shlibnamefile := p.target[:len(p.target)-2] + ".shlibname"
+		p.Internal.Target = p.Internal.Build.PkgObj
+		if cfg.BuildLinkshared {
+			shlibnamefile := p.Internal.Target[:len(p.Internal.Target)-2] + ".shlibname"
 			shlib, err := ioutil.ReadFile(shlibnamefile)
 			if err == nil {
 				libname := strings.TrimSpace(string(shlib))
-				if buildContext.Compiler == "gccgo" {
-					p.Shlib = filepath.Join(p.build.PkgTargetRoot, "shlibs", libname)
+				if cfg.BuildContext.Compiler == "gccgo" {
+					p.Shlib = filepath.Join(p.Internal.Build.PkgTargetRoot, "shlibs", libname)
 				} else {
-					p.Shlib = filepath.Join(p.build.PkgTargetRoot, libname)
+					p.Shlib = filepath.Join(p.Internal.Build.PkgTargetRoot, libname)
 
 				}
 			} else if !os.IsNotExist(err) {
-				fatalf("unexpected error reading %s: %v", shlibnamefile, err)
+				base.Fatalf("unexpected error reading %s: %v", shlibnamefile, err)
 			}
 		}
 	}
 
-	importPaths := p.Imports
+	ImportPaths := p.Imports
 	// Packages that use cgo import runtime/cgo implicitly.
 	// Packages that use cgo also import syscall implicitly,
 	// to wrap errno.
 	// Exclude certain packages to avoid circular dependencies.
 	if len(p.CgoFiles) > 0 && (!p.Standard || !cgoExclude[p.ImportPath]) {
-		importPaths = append(importPaths, "runtime/cgo")
+		ImportPaths = append(ImportPaths, "runtime/cgo")
 	}
 	if len(p.CgoFiles) > 0 && (!p.Standard || !cgoSyscallExclude[p.ImportPath]) {
-		importPaths = append(importPaths, "syscall")
+		ImportPaths = append(ImportPaths, "syscall")
 	}
 
-	if buildContext.CgoEnabled && p.Name == "main" && !p.Goroot {
+	if cfg.BuildContext.CgoEnabled && p.Name == "main" && !p.Goroot {
 		// Currently build modes c-shared, pie (on systems that do not
 		// support PIE with internal linking mode), plugin, and
 		// -linkshared force external linking mode, as of course does
 		// -ldflags=-linkmode=external. External linking mode forces
 		// an import of runtime/cgo.
-		pieCgo := buildBuildmode == "pie" && (buildContext.GOOS != "linux" || buildContext.GOARCH != "amd64")
+		pieCgo := cfg.BuildBuildmode == "pie" && (cfg.BuildContext.GOOS != "linux" || cfg.BuildContext.GOARCH != "amd64")
 		linkmodeExternal := false
-		for i, a := range buildLdflags {
+		for i, a := range cfg.BuildLdflags {
 			if a == "-linkmode=external" {
 				linkmodeExternal = true
 			}
-			if a == "-linkmode" && i+1 < len(buildLdflags) && buildLdflags[i+1] == "external" {
+			if a == "-linkmode" && i+1 < len(cfg.BuildLdflags) && cfg.BuildLdflags[i+1] == "external" {
 				linkmodeExternal = true
 			}
 		}
-		if buildBuildmode == "c-shared" || buildBuildmode == "plugin" || pieCgo || buildLinkshared || linkmodeExternal {
-			importPaths = append(importPaths, "runtime/cgo")
+		if cfg.BuildBuildmode == "c-shared" || cfg.BuildBuildmode == "plugin" || pieCgo || cfg.BuildLinkshared || linkmodeExternal {
+			ImportPaths = append(ImportPaths, "runtime/cgo")
 		}
 	}
 
 	// Everything depends on runtime, except runtime, its internal
 	// subpackages, and unsafe.
 	if !p.Standard || (p.ImportPath != "runtime" && !strings.HasPrefix(p.ImportPath, "runtime/internal/") && p.ImportPath != "unsafe") {
-		importPaths = append(importPaths, "runtime")
+		ImportPaths = append(ImportPaths, "runtime")
 		// When race detection enabled everything depends on runtime/race.
 		// Exclude certain packages to avoid circular dependencies.
-		if buildRace && (!p.Standard || !raceExclude[p.ImportPath]) {
-			importPaths = append(importPaths, "runtime/race")
+		if cfg.BuildRace && (!p.Standard || !raceExclude[p.ImportPath]) {
+			ImportPaths = append(ImportPaths, "runtime/race")
 		}
 		// MSan uses runtime/msan.
-		if buildMSan && (!p.Standard || !raceExclude[p.ImportPath]) {
-			importPaths = append(importPaths, "runtime/msan")
+		if cfg.BuildMSan && (!p.Standard || !raceExclude[p.ImportPath]) {
+			ImportPaths = append(ImportPaths, "runtime/msan")
 		}
 		// On ARM with GOARM=5, everything depends on math for the link.
-		if p.Name == "main" && goarch == "arm" {
-			importPaths = append(importPaths, "math")
+		if p.Name == "main" && cfg.Goarch == "arm" {
+			ImportPaths = append(ImportPaths, "math")
 		}
 	}
 
@@ -977,35 +1011,35 @@
 	// This can be an issue particularly for runtime/internal/atomic;
 	// see issue 13655.
 	if p.Standard && (p.ImportPath == "runtime" || strings.HasPrefix(p.ImportPath, "runtime/internal/")) && p.ImportPath != "runtime/internal/sys" {
-		importPaths = append(importPaths, "runtime/internal/sys")
+		ImportPaths = append(ImportPaths, "runtime/internal/sys")
 	}
 
 	// Build list of full paths to all Go files in the package,
 	// for use by commands like go fmt.
-	p.gofiles = stringList(p.GoFiles, p.CgoFiles, p.TestGoFiles, p.XTestGoFiles)
-	for i := range p.gofiles {
-		p.gofiles[i] = filepath.Join(p.Dir, p.gofiles[i])
+	p.Internal.GoFiles = str.StringList(p.GoFiles, p.CgoFiles, p.TestGoFiles, p.XTestGoFiles)
+	for i := range p.Internal.GoFiles {
+		p.Internal.GoFiles[i] = filepath.Join(p.Dir, p.Internal.GoFiles[i])
 	}
-	sort.Strings(p.gofiles)
+	sort.Strings(p.Internal.GoFiles)
 
-	p.sfiles = stringList(p.SFiles)
-	for i := range p.sfiles {
-		p.sfiles[i] = filepath.Join(p.Dir, p.sfiles[i])
+	p.Internal.SFiles = str.StringList(p.SFiles)
+	for i := range p.Internal.SFiles {
+		p.Internal.SFiles[i] = filepath.Join(p.Dir, p.Internal.SFiles[i])
 	}
-	sort.Strings(p.sfiles)
+	sort.Strings(p.Internal.SFiles)
 
-	p.allgofiles = stringList(p.IgnoredGoFiles)
-	for i := range p.allgofiles {
-		p.allgofiles[i] = filepath.Join(p.Dir, p.allgofiles[i])
+	p.Internal.AllGoFiles = str.StringList(p.IgnoredGoFiles)
+	for i := range p.Internal.AllGoFiles {
+		p.Internal.AllGoFiles[i] = filepath.Join(p.Dir, p.Internal.AllGoFiles[i])
 	}
-	p.allgofiles = append(p.allgofiles, p.gofiles...)
-	sort.Strings(p.allgofiles)
+	p.Internal.AllGoFiles = append(p.Internal.AllGoFiles, p.Internal.GoFiles...)
+	sort.Strings(p.Internal.AllGoFiles)
 
 	// Check for case-insensitive collision of input files.
 	// To avoid problems on case-insensitive files, we reject any package
 	// where two different input files have equal names under a case-insensitive
 	// comparison.
-	f1, f2 := foldDup(stringList(
+	f1, f2 := str.FoldDup(str.StringList(
 		p.GoFiles,
 		p.CgoFiles,
 		p.IgnoredGoFiles,
@@ -1023,7 +1057,7 @@
 	))
 	if f1 != "" {
 		p.Error = &PackageError{
-			ImportStack: stk.copy(),
+			ImportStack: stk.Copy(),
 			Err:         fmt.Sprintf("case-insensitive file name collision: %q and %q", f1, f2),
 		}
 		return p
@@ -1042,41 +1076,41 @@
 		}
 	}
 
-	for i, path := range importPaths {
+	for i, path := range ImportPaths {
 		if path == "C" {
 			continue
 		}
-		p1 := loadImport(path, p.Dir, p, stk, p.build.ImportPos[path], useVendor)
-		if !reqStdPkgSrc && p1.Standard {
+		p1 := LoadImport(path, p.Dir, p, stk, p.Internal.Build.ImportPos[path], UseVendor)
+		if cfg.BuildToolchainName == "gccgo" && p1.Standard {
 			continue
 		}
 		if p.Standard && p.Error == nil && !p1.Standard && p1.Error == nil {
 			p.Error = &PackageError{
-				ImportStack: stk.copy(),
+				ImportStack: stk.Copy(),
 				Err:         fmt.Sprintf("non-standard import %q in standard package %q", path, p.ImportPath),
 			}
-			pos := p.build.ImportPos[path]
+			pos := p.Internal.Build.ImportPos[path]
 			if len(pos) > 0 {
 				p.Error.Pos = pos[0].String()
 			}
 		}
 
 		path = p1.ImportPath
-		importPaths[i] = path
+		ImportPaths[i] = path
 		if i < len(p.Imports) {
 			p.Imports[i] = path
 		}
 
 		save(path, p1)
 		imports = append(imports, p1)
-		for _, dep := range p1.deps {
+		for _, dep := range p1.Internal.Deps {
 			save(dep.ImportPath, dep)
 		}
 		if p1.Incomplete {
 			p.Incomplete = true
 		}
 	}
-	p.imports = imports
+	p.Internal.Imports = imports
 
 	p.Deps = make([]string, 0, len(deps))
 	for dep := range deps {
@@ -1088,21 +1122,21 @@
 		if p1 == nil {
 			panic("impossible: missing entry in package cache for " + dep + " imported by " + p.ImportPath)
 		}
-		p.deps = append(p.deps, p1)
+		p.Internal.Deps = append(p.Internal.Deps, p1)
 		if p1.Error != nil {
 			p.DepsErrors = append(p.DepsErrors, p1.Error)
 		}
 	}
 
 	// unsafe is a fake package.
-	if p.Standard && (p.ImportPath == "unsafe" || buildContext.Compiler == "gccgo") {
-		p.target = ""
+	if p.Standard && (p.ImportPath == "unsafe" || cfg.BuildContext.Compiler == "gccgo") {
+		p.Internal.Target = ""
 	}
-	p.Target = p.target
+	p.Target = p.Internal.Target
 
 	// If cgo is not enabled, ignore cgo supporting sources
 	// just as we ignore go files containing import "C".
-	if !buildContext.CgoEnabled {
+	if !cfg.BuildContext.CgoEnabled {
 		p.CFiles = nil
 		p.CXXFiles = nil
 		p.MFiles = nil
@@ -1115,32 +1149,31 @@
 	}
 
 	// The gc toolchain only permits C source files with cgo.
-	if len(p.CFiles) > 0 && !p.usesCgo() && !p.usesSwig() && buildContext.Compiler == "gc" {
+	if len(p.CFiles) > 0 && !p.UsesCgo() && !p.UsesSwig() && cfg.BuildContext.Compiler == "gc" {
 		p.Error = &PackageError{
-			ImportStack: stk.copy(),
+			ImportStack: stk.Copy(),
 			Err:         fmt.Sprintf("C source files not allowed when not using cgo or SWIG: %s", strings.Join(p.CFiles, " ")),
 		}
 		return p
 	}
 
-	// In the absence of errors lower in the dependency tree,
-	// check for case-insensitive collisions of import paths.
-	if len(p.DepsErrors) == 0 {
-		dep1, dep2 := foldDup(p.Deps)
-		if dep1 != "" {
-			p.Error = &PackageError{
-				ImportStack: stk.copy(),
-				Err:         fmt.Sprintf("case-insensitive import collision: %q and %q", dep1, dep2),
-			}
-			return p
+	// Check for case-insensitive collisions of import paths.
+	fold := str.ToFold(p.ImportPath)
+	if other := foldPath[fold]; other == "" {
+		foldPath[fold] = p.ImportPath
+	} else if other != p.ImportPath {
+		p.Error = &PackageError{
+			ImportStack: stk.Copy(),
+			Err:         fmt.Sprintf("case-insensitive import collision: %q and %q", p.ImportPath, other),
 		}
+		return p
 	}
 
 	if p.BinaryOnly {
 		// For binary-only package, use build ID from supplied package binary.
-		buildID, err := readBuildID(p)
+		buildID, err := buildid.ReadBuildID(p.Name, p.Target)
 		if err == nil {
-			p.buildID = buildID
+			p.Internal.BuildID = buildID
 		}
 	} else {
 		computeBuildID(p)
@@ -1149,18 +1182,18 @@
 }
 
 // usesSwig reports whether the package needs to run SWIG.
-func (p *Package) usesSwig() bool {
+func (p *Package) UsesSwig() bool {
 	return len(p.SwigFiles) > 0 || len(p.SwigCXXFiles) > 0
 }
 
 // usesCgo reports whether the package needs to run cgo
-func (p *Package) usesCgo() bool {
+func (p *Package) UsesCgo() bool {
 	return len(p.CgoFiles) > 0
 }
 
 // packageList returns the list of packages in the dag rooted at roots
 // as visited in a depth-first post-order traversal.
-func packageList(roots []*Package) []*Package {
+func PackageList(roots []*Package) []*Package {
 	seen := map[*Package]bool{}
 	all := []*Package{}
 	var walk func(*Package)
@@ -1169,7 +1202,7 @@
 			return
 		}
 		seen[p] = true
-		for _, p1 := range p.imports {
+		for _, p1 := range p.Internal.Imports {
 			walk(p1)
 		}
 		all = append(all, p)
@@ -1182,8 +1215,8 @@
 
 // computeStale computes the Stale flag in the package dag that starts
 // at the named pkgs (command-line arguments).
-func computeStale(pkgs ...*Package) {
-	for _, p := range packageList(pkgs) {
+func ComputeStale(pkgs ...*Package) {
+	for _, p := range PackageList(pkgs) {
 		p.Stale, p.StaleReason = isStale(p)
 	}
 }
@@ -1458,7 +1491,7 @@
 // isStale reports whether package p needs to be rebuilt,
 // along with the reason why.
 func isStale(p *Package) (bool, string) {
-	if p.Standard && (p.ImportPath == "unsafe" || buildContext.Compiler == "gccgo") {
+	if p.Standard && (p.ImportPath == "unsafe" || cfg.BuildContext.Compiler == "gccgo") {
 		// fake, builtin package
 		return false, "builtin package"
 	}
@@ -1474,11 +1507,11 @@
 	// if a rebuild is needed, that rebuild attempt will produce a useful error.
 	// (Some commands, such as 'go list', do not attempt to rebuild.)
 	if p.BinaryOnly {
-		if p.target == "" {
+		if p.Internal.Target == "" {
 			// Fail if a build is attempted.
 			return true, "no source code for package, but no install target"
 		}
-		if _, err := os.Stat(p.target); err != nil {
+		if _, err := os.Stat(p.Internal.Target); err != nil {
 			// Fail if a build is attempted.
 			return true, "no source code for package, but cannot access install target: " + err.Error()
 		}
@@ -1486,17 +1519,17 @@
 	}
 
 	// If the -a flag is given, rebuild everything.
-	if buildA {
+	if cfg.BuildA {
 		return true, "build -a flag in use"
 	}
 
 	// If there's no install target, we have to rebuild.
-	if p.target == "" {
+	if p.Internal.Target == "" {
 		return true, "no install target"
 	}
 
 	// Package is stale if completely unbuilt.
-	fi, err := os.Stat(p.target)
+	fi, err := os.Stat(p.Internal.Target)
 	if err != nil {
 		return true, "cannot stat install target"
 	}
@@ -1509,13 +1542,13 @@
 	// It also catches changes in toolchain, like when flipping between
 	// two versions of Go compiling a single GOPATH.
 	// See issue 8290 and issue 10702.
-	targetBuildID, err := readBuildID(p)
-	if err == nil && targetBuildID != p.buildID {
+	targetBuildID, err := buildid.ReadBuildID(p.Name, p.Target)
+	if err == nil && targetBuildID != p.Internal.BuildID {
 		return true, "build ID mismatch"
 	}
 
 	// Package is stale if a dependency is.
-	for _, p1 := range p.deps {
+	for _, p1 := range p.Internal.Deps {
 		if p1.Stale {
 			return true, "stale dependency"
 		}
@@ -1553,8 +1586,8 @@
 	}
 
 	// Package is stale if a dependency is, or if a dependency is newer.
-	for _, p1 := range p.deps {
-		if p1.target != "" && olderThan(p1.target) {
+	for _, p1 := range p.Internal.Deps {
+		if p1.Internal.Target != "" && olderThan(p1.Internal.Target) {
 			return true, "newer dependency"
 		}
 	}
@@ -1572,11 +1605,11 @@
 	// and get a full rebuild anyway.
 	// Excluding $GOROOT used to also fix issue 4106, but that's now
 	// taken care of above (at least when the installed Go is a released version).
-	if p.Root != goroot {
-		if olderThan(buildToolchain.compiler()) {
+	if p.Root != cfg.GOROOT {
+		if olderThan(cfg.BuildToolchainCompiler()) {
 			return true, "newer compiler"
 		}
-		if p.build.IsCommand() && olderThan(buildToolchain.linker()) {
+		if p.Internal.Build.IsCommand() && olderThan(cfg.BuildToolchainLinker()) {
 			return true, "newer linker"
 		}
 	}
@@ -1619,7 +1652,7 @@
 	// to test for write access, and then skip GOPATH roots we don't have write
 	// access to. But hopefully we can just use the mtimes always.
 
-	srcs := stringList(p.GoFiles, p.CFiles, p.CXXFiles, p.MFiles, p.HFiles, p.FFiles, p.SFiles, p.CgoFiles, p.SysoFiles, p.SwigFiles, p.SwigCXXFiles)
+	srcs := str.StringList(p.GoFiles, p.CFiles, p.CXXFiles, p.MFiles, p.HFiles, p.FFiles, p.SFiles, p.CgoFiles, p.SysoFiles, p.SwigFiles, p.SwigCXXFiles)
 	for _, src := range srcs {
 		if olderThan(filepath.Join(p.Dir, src)) {
 			return true, "newer source file"
@@ -1629,7 +1662,7 @@
 	return false, ""
 }
 
-// computeBuildID computes the build ID for p, leaving it in p.buildID.
+// computeBuildID computes the build ID for p, leaving it in p.Internal.BuildID.
 // Build ID is a hash of the information we want to detect changes in.
 // See the long comment in isStale for details.
 func computeBuildID(p *Package) {
@@ -1637,11 +1670,12 @@
 
 	// Include the list of files compiled as part of the package.
 	// This lets us detect removed files. See issue 3895.
-	inputFiles := stringList(
+	inputFiles := str.StringList(
 		p.GoFiles,
 		p.CgoFiles,
 		p.CFiles,
 		p.CXXFiles,
+		p.FFiles,
 		p.MFiles,
 		p.HFiles,
 		p.SFiles,
@@ -1656,12 +1690,23 @@
 	// Include the content of runtime/internal/sys/zversion.go in the hash
 	// for package runtime. This will give package runtime a
 	// different build ID in each Go release.
-	if p.Standard && p.ImportPath == "runtime/internal/sys" && buildContext.Compiler != "gccgo" {
+	if p.Standard && p.ImportPath == "runtime/internal/sys" && cfg.BuildContext.Compiler != "gccgo" {
 		data, err := ioutil.ReadFile(filepath.Join(p.Dir, "zversion.go"))
-		if err != nil {
-			fatalf("go: %s", err)
+		if os.IsNotExist(err) {
+			p.Stale = true
+			p.StaleReason = fmt.Sprintf("missing zversion.go")
+		} else if err != nil {
+			base.Fatalf("go: %s", err)
 		}
 		fmt.Fprintf(h, "zversion %q\n", string(data))
+
+		// Add environment variables that affect code generation.
+		switch cfg.BuildContext.GOARCH {
+		case "arm":
+			fmt.Fprintf(h, "GOARM=%s\n", cfg.GOARM)
+		case "386":
+			fmt.Fprintf(h, "GO386=%s\n", cfg.GO386)
+		}
 	}
 
 	// Include the build IDs of any dependencies in the hash.
@@ -1672,22 +1717,26 @@
 	// people use the same GOPATH but switch between
 	// different Go releases. See issue 10702.
 	// This is also a better fix for issue 8290.
-	for _, p1 := range p.deps {
-		fmt.Fprintf(h, "dep %s %s\n", p1.ImportPath, p1.buildID)
+	for _, p1 := range p.Internal.Deps {
+		fmt.Fprintf(h, "dep %s %s\n", p1.ImportPath, p1.Internal.BuildID)
 	}
 
-	p.buildID = fmt.Sprintf("%x", h.Sum(nil))
+	p.Internal.BuildID = fmt.Sprintf("%x", h.Sum(nil))
 }
 
-var cwd, _ = os.Getwd()
-
 var cmdCache = map[string]*Package{}
 
+func ClearCmdCache() {
+	for name := range cmdCache {
+		delete(cmdCache, name)
+	}
+}
+
 // loadPackage is like loadImport but is used for command-line arguments,
 // not for paths found in import statements. In addition to ordinary import paths,
 // loadPackage accepts pseudo-paths beginning with cmd/ to denote commands
 // in the Go command directory, as well as paths to those directories.
-func loadPackage(arg string, stk *importStack) *Package {
+func LoadPackage(arg string, stk *ImportStack) *Package {
 	if build.IsLocalImport(arg) {
 		dir := arg
 		if !filepath.IsAbs(dir) {
@@ -1696,7 +1745,7 @@
 				dir = abs
 			}
 		}
-		if sub, ok := hasSubdir(gorootSrc, dir); ok && strings.HasPrefix(sub, "cmd/") && !strings.Contains(sub[4:], "/") {
+		if sub, ok := hasSubdir(cfg.GOROOTsrc, dir); ok && strings.HasPrefix(sub, "cmd/") && !strings.Contains(sub[4:], "/") {
 			arg = sub
 		}
 	}
@@ -1704,24 +1753,24 @@
 		if p := cmdCache[arg]; p != nil {
 			return p
 		}
-		stk.push(arg)
-		defer stk.pop()
+		stk.Push(arg)
+		defer stk.Pop()
 
-		bp, err := buildContext.ImportDir(filepath.Join(gorootSrc, arg), 0)
+		bp, err := cfg.BuildContext.ImportDir(filepath.Join(cfg.GOROOTsrc, arg), 0)
 		bp.ImportPath = arg
 		bp.Goroot = true
-		bp.BinDir = gorootBin
-		if gobin != "" {
-			bp.BinDir = gobin
+		bp.BinDir = cfg.GOROOTbin
+		if cfg.GOROOTbin != "" {
+			bp.BinDir = cfg.GOROOTbin
 		}
-		bp.Root = goroot
-		bp.SrcRoot = gorootSrc
+		bp.Root = cfg.GOROOT
+		bp.SrcRoot = cfg.GOROOTsrc
 		p := new(Package)
 		cmdCache[arg] = p
 		p.load(stk, bp, err)
 		if p.Error == nil && p.Name != "main" {
 			p.Error = &PackageError{
-				ImportStack: stk.copy(),
+				ImportStack: stk.Copy(),
 				Err:         fmt.Sprintf("expected package main but found package %s in %s", p.Name, p.Dir),
 			}
 		}
@@ -1735,28 +1784,28 @@
 	// referring to io/ioutil rather than a hypothetical import of
 	// "./ioutil".
 	if build.IsLocalImport(arg) {
-		bp, _ := buildContext.ImportDir(filepath.Join(cwd, arg), build.FindOnly)
+		bp, _ := cfg.BuildContext.ImportDir(filepath.Join(base.Cwd, arg), build.FindOnly)
 		if bp.ImportPath != "" && bp.ImportPath != "." {
 			arg = bp.ImportPath
 		}
 	}
 
-	return loadImport(arg, cwd, nil, stk, nil, 0)
+	return LoadImport(arg, base.Cwd, nil, stk, nil, 0)
 }
 
 // packages returns the packages named by the
-// command line arguments 'args'.  If a named package
+// command line arguments 'args'. If a named package
 // cannot be loaded at all (for example, if the directory does not exist),
 // then packages prints an error and does not include that
 // package in the results. However, if errors occur trying
 // to load dependencies of a named package, the named
 // package is still returned, with p.Incomplete = true
 // and details in p.DepsErrors.
-func packages(args []string) []*Package {
+func Packages(args []string) []*Package {
 	var pkgs []*Package
-	for _, pkg := range packagesAndErrors(args) {
+	for _, pkg := range PackagesAndErrors(args) {
 		if pkg.Error != nil {
-			errorf("can't load package: %s", pkg.Error)
+			base.Errorf("can't load package: %s", pkg.Error)
 			continue
 		}
 		pkgs = append(pkgs, pkg)
@@ -1768,15 +1817,15 @@
 // *Package for every argument, even the ones that
 // cannot be loaded at all.
 // The packages that fail to load will have p.Error != nil.
-func packagesAndErrors(args []string) []*Package {
+func PackagesAndErrors(args []string) []*Package {
 	if len(args) > 0 && strings.HasSuffix(args[0], ".go") {
-		return []*Package{goFilesPackage(args)}
+		return []*Package{GoFilesPackage(args)}
 	}
 
-	args = importPaths(args)
+	args = ImportPaths(args)
 	var (
 		pkgs    []*Package
-		stk     importStack
+		stk     ImportStack
 		seenArg = make(map[string]bool)
 		seenPkg = make(map[*Package]bool)
 	)
@@ -1786,14 +1835,14 @@
 			continue
 		}
 		seenArg[arg] = true
-		pkg := loadPackage(arg, &stk)
+		pkg := LoadPackage(arg, &stk)
 		if seenPkg[pkg] {
 			continue
 		}
 		seenPkg[pkg] = true
 		pkgs = append(pkgs, pkg)
 	}
-	computeStale(pkgs...)
+	ComputeStale(pkgs...)
 
 	return pkgs
 }
@@ -1801,12 +1850,12 @@
 // packagesForBuild is like 'packages' but fails if any of
 // the packages or their dependencies have errors
 // (cannot be built).
-func packagesForBuild(args []string) []*Package {
-	pkgs := packagesAndErrors(args)
+func PackagesForBuild(args []string) []*Package {
+	pkgs := PackagesAndErrors(args)
 	printed := map[*PackageError]bool{}
 	for _, pkg := range pkgs {
 		if pkg.Error != nil {
-			errorf("can't load package: %s", pkg.Error)
+			base.Errorf("can't load package: %s", pkg.Error)
 		}
 		for _, err := range pkg.DepsErrors {
 			// Since these are errors in dependencies,
@@ -1815,11 +1864,11 @@
 			// Only print each once.
 			if !printed[err] {
 				printed[err] = true
-				errorf("%s", err)
+				base.Errorf("%s", err)
 			}
 		}
 	}
-	exitIfErrors()
+	base.ExitIfErrors()
 
 	// Check for duplicate loads of the same package.
 	// That should be impossible, but if it does happen then
@@ -1828,223 +1877,95 @@
 	// which doesn't work very well.
 	seen := map[string]bool{}
 	reported := map[string]bool{}
-	for _, pkg := range packageList(pkgs) {
+	for _, pkg := range PackageList(pkgs) {
 		if seen[pkg.ImportPath] && !reported[pkg.ImportPath] {
 			reported[pkg.ImportPath] = true
-			errorf("internal error: duplicate loads of %s", pkg.ImportPath)
+			base.Errorf("internal error: duplicate loads of %s", pkg.ImportPath)
 		}
 		seen[pkg.ImportPath] = true
 	}
-	exitIfErrors()
+	base.ExitIfErrors()
 
 	return pkgs
 }
 
-// hasSubdir reports whether dir is a subdirectory of
-// (possibly multiple levels below) root.
-// If so, it sets rel to the path fragment that must be
-// appended to root to reach dir.
-func hasSubdir(root, dir string) (rel string, ok bool) {
-	if p, err := filepath.EvalSymlinks(root); err == nil {
-		root = p
-	}
-	if p, err := filepath.EvalSymlinks(dir); err == nil {
-		dir = p
-	}
-	const sep = string(filepath.Separator)
-	root = filepath.Clean(root)
-	if !strings.HasSuffix(root, sep) {
-		root += sep
-	}
-	dir = filepath.Clean(dir)
-	if !strings.HasPrefix(dir, root) {
-		return "", false
-	}
-	return filepath.ToSlash(dir[len(root):]), true
-}
-
-var (
-	errBuildIDToolchain = fmt.Errorf("build ID only supported in gc toolchain")
-	errBuildIDMalformed = fmt.Errorf("malformed object file")
-	errBuildIDUnknown   = fmt.Errorf("lost build ID")
-)
-
-var (
-	bangArch = []byte("!<arch>")
-	pkgdef   = []byte("__.PKGDEF")
-	goobject = []byte("go object ")
-	buildid  = []byte("build id ")
-)
-
-// readBuildID reads the build ID from an archive or binary.
-// It only supports the gc toolchain.
-// Other toolchain maintainers should adjust this function.
-func readBuildID(p *Package) (id string, err error) {
-	if buildToolchain != (gcToolchain{}) {
-		return "", errBuildIDToolchain
-	}
-
-	// For commands, read build ID directly from binary.
-	if p.Name == "main" {
-		return ReadBuildIDFromBinary(p.Target)
-	}
-
-	// Otherwise, we expect to have an archive (.a) file,
-	// and we can read the build ID from the Go export data.
-	if !strings.HasSuffix(p.Target, ".a") {
-		return "", &os.PathError{Op: "parse", Path: p.Target, Err: errBuildIDUnknown}
-	}
-
-	// Read just enough of the target to fetch the build ID.
-	// The archive is expected to look like:
-	//
-	//	!<arch>
-	//	__.PKGDEF       0           0     0     644     7955      `
-	//	go object darwin amd64 devel X:none
-	//	build id "b41e5c45250e25c9fd5e9f9a1de7857ea0d41224"
-	//
-	// The variable-sized strings are GOOS, GOARCH, and the experiment list (X:none).
-	// Reading the first 1024 bytes should be plenty.
-	f, err := os.Open(p.Target)
-	if err != nil {
-		return "", err
-	}
-	data := make([]byte, 1024)
-	n, err := io.ReadFull(f, data)
-	f.Close()
-
-	if err != nil && n == 0 {
-		return "", err
-	}
-
-	bad := func() (string, error) {
-		return "", &os.PathError{Op: "parse", Path: p.Target, Err: errBuildIDMalformed}
-	}
-
-	// Archive header.
-	for i := 0; ; i++ { // returns during i==3
-		j := bytes.IndexByte(data, '\n')
-		if j < 0 {
-			return bad()
-		}
-		line := data[:j]
-		data = data[j+1:]
-		switch i {
-		case 0:
-			if !bytes.Equal(line, bangArch) {
-				return bad()
-			}
-		case 1:
-			if !bytes.HasPrefix(line, pkgdef) {
-				return bad()
-			}
-		case 2:
-			if !bytes.HasPrefix(line, goobject) {
-				return bad()
-			}
-		case 3:
-			if !bytes.HasPrefix(line, buildid) {
-				// Found the object header, just doesn't have a build id line.
-				// Treat as successful, with empty build id.
-				return "", nil
-			}
-			id, err := strconv.Unquote(string(line[len(buildid):]))
-			if err != nil {
-				return bad()
-			}
-			return id, nil
-		}
-	}
-}
-
-var (
-	goBuildPrefix = []byte("\xff Go build ID: \"")
-	goBuildEnd    = []byte("\"\n \xff")
-
-	elfPrefix = []byte("\x7fELF")
-
-	machoPrefixes = [][]byte{
-		{0xfe, 0xed, 0xfa, 0xce},
-		{0xfe, 0xed, 0xfa, 0xcf},
-		{0xce, 0xfa, 0xed, 0xfe},
-		{0xcf, 0xfa, 0xed, 0xfe},
-	}
-)
-
-var BuildIDReadSize = 32 * 1024 // changed for testing
-
-// ReadBuildIDFromBinary reads the build ID from a binary.
-//
-// ELF binaries store the build ID in a proper PT_NOTE section.
-//
-// Other binary formats are not so flexible. For those, the linker
-// stores the build ID as non-instruction bytes at the very beginning
-// of the text segment, which should appear near the beginning
-// of the file. This is clumsy but fairly portable. Custom locations
-// can be added for other binary types as needed, like we did for ELF.
-func ReadBuildIDFromBinary(filename string) (id string, err error) {
-	if filename == "" {
-		return "", &os.PathError{Op: "parse", Path: filename, Err: errBuildIDUnknown}
-	}
-
-	// Read the first 32 kB of the binary file.
-	// That should be enough to find the build ID.
-	// In ELF files, the build ID is in the leading headers,
-	// which are typically less than 4 kB, not to mention 32 kB.
-	// In Mach-O files, there's no limit, so we have to parse the file.
-	// On other systems, we're trying to read enough that
-	// we get the beginning of the text segment in the read.
-	// The offset where the text segment begins in a hello
-	// world compiled for each different object format today:
-	//
-	//	Plan 9: 0x20
-	//	Windows: 0x600
-	//
-	f, err := os.Open(filename)
-	if err != nil {
-		return "", err
-	}
-	defer f.Close()
-
-	data := make([]byte, BuildIDReadSize)
-	_, err = io.ReadFull(f, data)
-	if err == io.ErrUnexpectedEOF {
-		err = nil
-	}
-	if err != nil {
-		return "", err
-	}
-
-	if bytes.HasPrefix(data, elfPrefix) {
-		return readELFGoBuildID(filename, f, data)
-	}
-	for _, m := range machoPrefixes {
-		if bytes.HasPrefix(data, m) {
-			return readMachoGoBuildID(filename, f, data)
+// GoFilesPackage creates a package for building a collection of Go files
+// (typically named on the command line). The target is named p.a for
+// package p or named after the first Go file for package main.
+func GoFilesPackage(gofiles []string) *Package {
+	// TODO: Remove this restriction.
+	for _, f := range gofiles {
+		if !strings.HasSuffix(f, ".go") {
+			base.Fatalf("named files must be .go files")
 		}
 	}
 
-	return readRawGoBuildID(filename, data)
-}
+	var stk ImportStack
+	ctxt := cfg.BuildContext
+	ctxt.UseAllFiles = true
 
-// readRawGoBuildID finds the raw build ID stored in text segment data.
-func readRawGoBuildID(filename string, data []byte) (id string, err error) {
-	i := bytes.Index(data, goBuildPrefix)
-	if i < 0 {
-		// Missing. Treat as successful but build ID empty.
-		return "", nil
+	// Synthesize fake "directory" that only shows the named files,
+	// to make it look like this is a standard package or
+	// command directory. So that local imports resolve
+	// consistently, the files must all be in the same directory.
+	var dirent []os.FileInfo
+	var dir string
+	for _, file := range gofiles {
+		fi, err := os.Stat(file)
+		if err != nil {
+			base.Fatalf("%s", err)
+		}
+		if fi.IsDir() {
+			base.Fatalf("%s is a directory, should be a Go file", file)
+		}
+		dir1, _ := filepath.Split(file)
+		if dir1 == "" {
+			dir1 = "./"
+		}
+		if dir == "" {
+			dir = dir1
+		} else if dir != dir1 {
+			base.Fatalf("named files must all be in one directory; have %s and %s", dir, dir1)
+		}
+		dirent = append(dirent, fi)
 	}
+	ctxt.ReadDir = func(string) ([]os.FileInfo, error) { return dirent, nil }
 
-	j := bytes.Index(data[i+len(goBuildPrefix):], goBuildEnd)
-	if j < 0 {
-		return "", &os.PathError{Op: "parse", Path: filename, Err: errBuildIDMalformed}
+	var err error
+	if dir == "" {
+		dir = base.Cwd
 	}
-
-	quoted := data[i+len(goBuildPrefix)-1 : i+len(goBuildPrefix)+j+1]
-	id, err = strconv.Unquote(string(quoted))
+	dir, err = filepath.Abs(dir)
 	if err != nil {
-		return "", &os.PathError{Op: "parse", Path: filename, Err: errBuildIDMalformed}
+		base.Fatalf("%s", err)
 	}
 
-	return id, nil
+	bp, err := ctxt.ImportDir(dir, 0)
+	pkg := new(Package)
+	pkg.Internal.Local = true
+	pkg.Internal.Cmdline = true
+	stk.Push("main")
+	pkg.load(&stk, bp, err)
+	stk.Pop()
+	pkg.Internal.LocalPrefix = dirToImportPath(dir)
+	pkg.ImportPath = "command-line-arguments"
+	pkg.Internal.Target = ""
+
+	if pkg.Name == "main" {
+		_, elem := filepath.Split(gofiles[0])
+		exe := elem[:len(elem)-len(".go")] + cfg.ExeSuffix
+		if cfg.BuildO == "" {
+			cfg.BuildO = exe
+		}
+		if cfg.GOBIN != "" {
+			pkg.Internal.Target = filepath.Join(cfg.GOBIN, exe)
+		}
+	}
+
+	pkg.Target = pkg.Internal.Target
+	pkg.Stale = true
+	pkg.StaleReason = "files named on command line"
+
+	ComputeStale(pkg)
+	return pkg
 }
diff --git a/libgo/go/cmd/go/internal/load/search.go b/libgo/go/cmd/go/internal/load/search.go
new file mode 100644
index 0000000..0c7d9ce
--- /dev/null
+++ b/libgo/go/cmd/go/internal/load/search.go
@@ -0,0 +1,338 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package load
+
+import (
+	"cmd/go/internal/cfg"
+	"fmt"
+	"go/build"
+	"log"
+	"os"
+	"path"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+// allPackages returns all the packages that can be found
+// under the $GOPATH directories and $GOROOT matching pattern.
+// The pattern is either "all" (all packages), "std" (standard packages),
+// "cmd" (standard commands), or a path including "...".
+func allPackages(pattern string) []string {
+	pkgs := MatchPackages(pattern)
+	if len(pkgs) == 0 {
+		fmt.Fprintf(os.Stderr, "warning: %q matched no packages\n", pattern)
+	}
+	return pkgs
+}
+
+// allPackagesInFS is like allPackages but is passed a pattern
+// beginning ./ or ../, meaning it should scan the tree rooted
+// at the given directory. There are ... in the pattern too.
+func allPackagesInFS(pattern string) []string {
+	pkgs := MatchPackagesInFS(pattern)
+	if len(pkgs) == 0 {
+		fmt.Fprintf(os.Stderr, "warning: %q matched no packages\n", pattern)
+	}
+	return pkgs
+}
+
+// MatchPackages returns a list of package paths matching pattern
+// (see go help packages for pattern syntax).
+func MatchPackages(pattern string) []string {
+	match := func(string) bool { return true }
+	treeCanMatch := func(string) bool { return true }
+	if !IsMetaPackage(pattern) {
+		match = matchPattern(pattern)
+		treeCanMatch = treeCanMatchPattern(pattern)
+	}
+
+	have := map[string]bool{
+		"builtin": true, // ignore pseudo-package that exists only for documentation
+	}
+	if !cfg.BuildContext.CgoEnabled {
+		have["runtime/cgo"] = true // ignore during walk
+	}
+	var pkgs []string
+
+	for _, src := range cfg.BuildContext.SrcDirs() {
+		if (pattern == "std" || pattern == "cmd") && src != cfg.GOROOTsrc {
+			continue
+		}
+		src = filepath.Clean(src) + string(filepath.Separator)
+		root := src
+		if pattern == "cmd" {
+			root += "cmd" + string(filepath.Separator)
+		}
+		filepath.Walk(root, func(path string, fi os.FileInfo, err error) error {
+			if err != nil || path == src {
+				return nil
+			}
+
+			want := true
+			// Avoid .foo, _foo, and testdata directory trees.
+			_, elem := filepath.Split(path)
+			if strings.HasPrefix(elem, ".") || strings.HasPrefix(elem, "_") || elem == "testdata" {
+				want = false
+			}
+
+			name := filepath.ToSlash(path[len(src):])
+			if pattern == "std" && (!isStandardImportPath(name) || name == "cmd") {
+				// The name "std" is only the standard library.
+				// If the name is cmd, it's the root of the command tree.
+				want = false
+			}
+			if !treeCanMatch(name) {
+				want = false
+			}
+
+			if !fi.IsDir() {
+				if fi.Mode()&os.ModeSymlink != 0 && want {
+					if target, err := os.Stat(path); err == nil && target.IsDir() {
+						fmt.Fprintf(os.Stderr, "warning: ignoring symlink %s\n", path)
+					}
+				}
+				return nil
+			}
+			if !want {
+				return filepath.SkipDir
+			}
+
+			if have[name] {
+				return nil
+			}
+			have[name] = true
+			if !match(name) {
+				return nil
+			}
+			pkg, err := cfg.BuildContext.ImportDir(path, 0)
+			if err != nil {
+				if _, noGo := err.(*build.NoGoError); noGo {
+					return nil
+				}
+			}
+
+			// If we are expanding "cmd", skip main
+			// packages under cmd/vendor. At least as of
+			// March, 2017, there is one there for the
+			// vendored pprof tool.
+			if pattern == "cmd" && strings.HasPrefix(pkg.ImportPath, "cmd/vendor") && pkg.Name == "main" {
+				return nil
+			}
+
+			pkgs = append(pkgs, name)
+			return nil
+		})
+	}
+	return pkgs
+}
+
+// MatchPackagesInFS returns a list of package paths matching pattern,
+// which must begin with ./ or ../
+// (see go help packages for pattern syntax).
+func MatchPackagesInFS(pattern string) []string {
+	// Find directory to begin the scan.
+	// Could be smarter but this one optimization
+	// is enough for now, since ... is usually at the
+	// end of a path.
+	i := strings.Index(pattern, "...")
+	dir, _ := path.Split(pattern[:i])
+
+	// pattern begins with ./ or ../.
+	// path.Clean will discard the ./ but not the ../.
+	// We need to preserve the ./ for pattern matching
+	// and in the returned import paths.
+	prefix := ""
+	if strings.HasPrefix(pattern, "./") {
+		prefix = "./"
+	}
+	match := matchPattern(pattern)
+
+	var pkgs []string
+	filepath.Walk(dir, func(path string, fi os.FileInfo, err error) error {
+		if err != nil || !fi.IsDir() {
+			return nil
+		}
+		if path == dir {
+			// filepath.Walk starts at dir and recurses. For the recursive case,
+			// the path is the result of filepath.Join, which calls filepath.Clean.
+			// The initial case is not Cleaned, though, so we do this explicitly.
+			//
+			// This converts a path like "./io/" to "io". Without this step, running
+			// "cd $GOROOT/src; go list ./io/..." would incorrectly skip the io
+			// package, because prepending the prefix "./" to the unclean path would
+			// result in "././io", and match("././io") returns false.
+			path = filepath.Clean(path)
+		}
+
+		// Avoid .foo, _foo, and testdata directory trees, but do not avoid "." or "..".
+		_, elem := filepath.Split(path)
+		dot := strings.HasPrefix(elem, ".") && elem != "." && elem != ".."
+		if dot || strings.HasPrefix(elem, "_") || elem == "testdata" {
+			return filepath.SkipDir
+		}
+
+		name := prefix + filepath.ToSlash(path)
+		if !match(name) {
+			return nil
+		}
+
+		// We keep the directory if we can import it, or if we can't import it
+		// due to invalid Go source files. This means that directories containing
+		// parse errors will be built (and fail) instead of being silently skipped
+		// as not matching the pattern. Go 1.5 and earlier skipped, but that
+		// behavior means people miss serious mistakes.
+		// See golang.org/issue/11407.
+		if p, err := cfg.BuildContext.ImportDir(path, 0); err != nil && (p == nil || len(p.InvalidGoFiles) == 0) {
+			if _, noGo := err.(*build.NoGoError); !noGo {
+				log.Print(err)
+			}
+			return nil
+		}
+		pkgs = append(pkgs, name)
+		return nil
+	})
+	return pkgs
+}
+
+// treeCanMatchPattern(pattern)(name) reports whether
+// name or children of name can possibly match pattern.
+// Pattern is the same limited glob accepted by matchPattern.
+func treeCanMatchPattern(pattern string) func(name string) bool {
+	wildCard := false
+	if i := strings.Index(pattern, "..."); i >= 0 {
+		wildCard = true
+		pattern = pattern[:i]
+	}
+	return func(name string) bool {
+		return len(name) <= len(pattern) && hasPathPrefix(pattern, name) ||
+			wildCard && strings.HasPrefix(name, pattern)
+	}
+}
+
+// matchPattern(pattern)(name) reports whether
+// name matches pattern. Pattern is a limited glob
+// pattern in which '...' means 'any string' and there
+// is no other special syntax.
+// Unfortunately, there are two special cases. Quoting "go help packages":
+//
+// First, /... at the end of the pattern can match an empty string,
+// so that net/... matches both net and packages in its subdirectories, like net/http.
+// Second, any slash-separted pattern element containing a wildcard never
+// participates in a match of the "vendor" element in the path of a vendored
+// package, so that ./... does not match packages in subdirectories of
+// ./vendor or ./mycode/vendor, but ./vendor/... and ./mycode/vendor/... do.
+// Note, however, that a directory named vendor that itself contains code
+// is not a vendored package: cmd/vendor would be a command named vendor,
+// and the pattern cmd/... matches it.
+func matchPattern(pattern string) func(name string) bool {
+	// Convert pattern to regular expression.
+	// The strategy for the trailing /... is to nest it in an explicit ? expression.
+	// The strategy for the vendor exclusion is to change the unmatchable
+	// vendor strings to a disallowed code point (vendorChar) and to use
+	// "(anything but that codepoint)*" as the implementation of the ... wildcard.
+	// This is a bit complicated but the obvious alternative,
+	// namely a hand-written search like in most shell glob matchers,
+	// is too easy to make accidentally exponential.
+	// Using package regexp guarantees linear-time matching.
+
+	const vendorChar = "\x00"
+
+	if strings.Contains(pattern, vendorChar) {
+		return func(name string) bool { return false }
+	}
+
+	re := regexp.QuoteMeta(pattern)
+	re = replaceVendor(re, vendorChar)
+	switch {
+	case strings.HasSuffix(re, `/`+vendorChar+`/\.\.\.`):
+		re = strings.TrimSuffix(re, `/`+vendorChar+`/\.\.\.`) + `(/vendor|/` + vendorChar + `/\.\.\.)`
+	case re == vendorChar+`/\.\.\.`:
+		re = `(/vendor|/` + vendorChar + `/\.\.\.)`
+	case strings.HasSuffix(re, `/\.\.\.`):
+		re = strings.TrimSuffix(re, `/\.\.\.`) + `(/\.\.\.)?`
+	}
+	re = strings.Replace(re, `\.\.\.`, `[^`+vendorChar+`]*`, -1)
+
+	reg := regexp.MustCompile(`^` + re + `$`)
+
+	return func(name string) bool {
+		if strings.Contains(name, vendorChar) {
+			return false
+		}
+		return reg.MatchString(replaceVendor(name, vendorChar))
+	}
+}
+
+// replaceVendor returns the result of replacing
+// non-trailing vendor path elements in x with repl.
+func replaceVendor(x, repl string) string {
+	if !strings.Contains(x, "vendor") {
+		return x
+	}
+	elem := strings.Split(x, "/")
+	for i := 0; i < len(elem)-1; i++ {
+		if elem[i] == "vendor" {
+			elem[i] = repl
+		}
+	}
+	return strings.Join(elem, "/")
+}
+
+// ImportPaths returns the import paths to use for the given command line.
+func ImportPaths(args []string) []string {
+	args = ImportPathsNoDotExpansion(args)
+	var out []string
+	for _, a := range args {
+		if strings.Contains(a, "...") {
+			if build.IsLocalImport(a) {
+				out = append(out, allPackagesInFS(a)...)
+			} else {
+				out = append(out, allPackages(a)...)
+			}
+			continue
+		}
+		out = append(out, a)
+	}
+	return out
+}
+
+// ImportPathsNoDotExpansion returns the import paths to use for the given
+// command line, but it does no ... expansion.
+func ImportPathsNoDotExpansion(args []string) []string {
+	if len(args) == 0 {
+		return []string{"."}
+	}
+	var out []string
+	for _, a := range args {
+		// Arguments are supposed to be import paths, but
+		// as a courtesy to Windows developers, rewrite \ to /
+		// in command-line arguments. Handles .\... and so on.
+		if filepath.Separator == '\\' {
+			a = strings.Replace(a, `\`, `/`, -1)
+		}
+
+		// Put argument in canonical form, but preserve leading ./.
+		if strings.HasPrefix(a, "./") {
+			a = "./" + path.Clean(a)
+			if a == "./." {
+				a = "."
+			}
+		} else {
+			a = path.Clean(a)
+		}
+		if IsMetaPackage(a) {
+			out = append(out, allPackages(a)...)
+			continue
+		}
+		out = append(out, a)
+	}
+	return out
+}
+
+// isMetaPackage checks if name is a reserved package name that expands to multiple packages.
+func IsMetaPackage(name string) bool {
+	return name == "std" || name == "cmd" || name == "all"
+}
diff --git a/libgo/go/cmd/go/testgo.go b/libgo/go/cmd/go/internal/load/testgo.go
similarity index 97%
rename from libgo/go/cmd/go/testgo.go
rename to libgo/go/cmd/go/internal/load/testgo.go
index e507f34..7734048 100644
--- a/libgo/go/cmd/go/testgo.go
+++ b/libgo/go/cmd/go/internal/load/testgo.go
@@ -10,7 +10,7 @@
 
 // +build testgo
 
-package main
+package load
 
 import "os"
 
diff --git a/libgo/go/cmd/go/internal/run/run.go b/libgo/go/cmd/go/internal/run/run.go
new file mode 100644
index 0000000..6e276c2
--- /dev/null
+++ b/libgo/go/cmd/go/internal/run/run.go
@@ -0,0 +1,131 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package run implements the ``go run'' command.
+package run
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/str"
+	"cmd/go/internal/work"
+)
+
+var CmdRun = &base.Command{
+	UsageLine: "run [build flags] [-exec xprog] gofiles... [arguments...]",
+	Short:     "compile and run Go program",
+	Long: `
+Run compiles and runs the main package comprising the named Go source files.
+A Go source file is defined to be a file ending in a literal ".go" suffix.
+
+By default, 'go run' runs the compiled binary directly: 'a.out arguments...'.
+If the -exec flag is given, 'go run' invokes the binary using xprog:
+	'xprog a.out arguments...'.
+If the -exec flag is not given, GOOS or GOARCH is different from the system
+default, and a program named go_$GOOS_$GOARCH_exec can be found
+on the current search path, 'go run' invokes the binary using that program,
+for example 'go_nacl_386_exec a.out arguments...'. This allows execution of
+cross-compiled programs when a simulator or other execution method is
+available.
+
+For more about build flags, see 'go help build'.
+
+See also: go build.
+	`,
+}
+
+func init() {
+	CmdRun.Run = runRun // break init loop
+
+	work.AddBuildFlags(CmdRun)
+	CmdRun.Flag.Var((*base.StringsFlag)(&work.ExecCmd), "exec", "")
+}
+
+func printStderr(args ...interface{}) (int, error) {
+	return fmt.Fprint(os.Stderr, args...)
+}
+
+func runRun(cmd *base.Command, args []string) {
+	work.InstrumentInit()
+	work.BuildModeInit()
+	var b work.Builder
+	b.Init()
+	b.Print = printStderr
+	i := 0
+	for i < len(args) && strings.HasSuffix(args[i], ".go") {
+		i++
+	}
+	files, cmdArgs := args[:i], args[i:]
+	if len(files) == 0 {
+		base.Fatalf("go run: no go files listed")
+	}
+	for _, file := range files {
+		if strings.HasSuffix(file, "_test.go") {
+			// GoFilesPackage is going to assign this to TestGoFiles.
+			// Reject since it won't be part of the build.
+			base.Fatalf("go run: cannot run *_test.go files (%s)", file)
+		}
+	}
+	p := load.GoFilesPackage(files)
+	if p.Error != nil {
+		base.Fatalf("%s", p.Error)
+	}
+	p.Internal.OmitDebug = true
+	if len(p.DepsErrors) > 0 {
+		// Since these are errors in dependencies,
+		// the same error might show up multiple times,
+		// once in each package that depends on it.
+		// Only print each once.
+		printed := map[*load.PackageError]bool{}
+		for _, err := range p.DepsErrors {
+			if !printed[err] {
+				printed[err] = true
+				base.Errorf("%s", err)
+			}
+		}
+	}
+	base.ExitIfErrors()
+	if p.Name != "main" {
+		base.Fatalf("go run: cannot run non-main package")
+	}
+	p.Internal.Target = "" // must build - not up to date
+	var src string
+	if len(p.GoFiles) > 0 {
+		src = p.GoFiles[0]
+	} else if len(p.CgoFiles) > 0 {
+		src = p.CgoFiles[0]
+	} else {
+		// this case could only happen if the provided source uses cgo
+		// while cgo is disabled.
+		hint := ""
+		if !cfg.BuildContext.CgoEnabled {
+			hint = " (cgo is disabled)"
+		}
+		base.Fatalf("go run: no suitable source files%s", hint)
+	}
+	p.Internal.ExeName = src[:len(src)-len(".go")] // name temporary executable for first go file
+	a1 := b.Action(work.ModeBuild, work.ModeBuild, p)
+	a := &work.Action{Func: buildRunProgram, Args: cmdArgs, Deps: []*work.Action{a1}}
+	b.Do(a)
+}
+
+// buildRunProgram is the action for running a binary that has already
+// been compiled. We ignore exit status.
+func buildRunProgram(b *work.Builder, a *work.Action) error {
+	cmdline := str.StringList(work.FindExecCmd(), a.Deps[0].Target, a.Args)
+	if cfg.BuildN || cfg.BuildX {
+		b.Showcmd("", "%s", strings.Join(cmdline, " "))
+		if cfg.BuildN {
+			return nil
+		}
+	}
+
+	base.RunStdin(cmdline)
+	return nil
+}
diff --git a/libgo/go/cmd/go/internal/str/str.go b/libgo/go/cmd/go/internal/str/str.go
new file mode 100644
index 0000000..0413ed8
--- /dev/null
+++ b/libgo/go/cmd/go/internal/str/str.go
@@ -0,0 +1,141 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package str provides string manipulation utilities.
+package str
+
+import (
+	"bytes"
+	"fmt"
+	"unicode"
+	"unicode/utf8"
+)
+
+// StringList flattens its arguments into a single []string.
+// Each argument in args must have type string or []string.
+func StringList(args ...interface{}) []string {
+	var x []string
+	for _, arg := range args {
+		switch arg := arg.(type) {
+		case []string:
+			x = append(x, arg...)
+		case string:
+			x = append(x, arg)
+		default:
+			panic("stringList: invalid argument of type " + fmt.Sprintf("%T", arg))
+		}
+	}
+	return x
+}
+
+// ToFold returns a string with the property that
+//	strings.EqualFold(s, t) iff ToFold(s) == ToFold(t)
+// This lets us test a large set of strings for fold-equivalent
+// duplicates without making a quadratic number of calls
+// to EqualFold. Note that strings.ToUpper and strings.ToLower
+// do not have the desired property in some corner cases.
+func ToFold(s string) string {
+	// Fast path: all ASCII, no upper case.
+	// Most paths look like this already.
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= utf8.RuneSelf || 'A' <= c && c <= 'Z' {
+			goto Slow
+		}
+	}
+	return s
+
+Slow:
+	var buf bytes.Buffer
+	for _, r := range s {
+		// SimpleFold(x) cycles to the next equivalent rune > x
+		// or wraps around to smaller values. Iterate until it wraps,
+		// and we've found the minimum value.
+		for {
+			r0 := r
+			r = unicode.SimpleFold(r0)
+			if r <= r0 {
+				break
+			}
+		}
+		// Exception to allow fast path above: A-Z => a-z
+		if 'A' <= r && r <= 'Z' {
+			r += 'a' - 'A'
+		}
+		buf.WriteRune(r)
+	}
+	return buf.String()
+}
+
+// FoldDup reports a pair of strings from the list that are
+// equal according to strings.EqualFold.
+// It returns "", "" if there are no such strings.
+func FoldDup(list []string) (string, string) {
+	clash := map[string]string{}
+	for _, s := range list {
+		fold := ToFold(s)
+		if t := clash[fold]; t != "" {
+			if s > t {
+				s, t = t, s
+			}
+			return s, t
+		}
+		clash[fold] = s
+	}
+	return "", ""
+}
+
+// Contains reports whether x contains s.
+func Contains(x []string, s string) bool {
+	for _, t := range x {
+		if t == s {
+			return true
+		}
+	}
+	return false
+}
+
+func isSpaceByte(c byte) bool {
+	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
+}
+
+// SplitQuotedFields splits s into a list of fields,
+// allowing single or double quotes around elements.
+// There is no unescaping or other processing within
+// quoted fields.
+func SplitQuotedFields(s string) ([]string, error) {
+	// Split fields allowing '' or "" around elements.
+	// Quotes further inside the string do not count.
+	var f []string
+	for len(s) > 0 {
+		for len(s) > 0 && isSpaceByte(s[0]) {
+			s = s[1:]
+		}
+		if len(s) == 0 {
+			break
+		}
+		// Accepted quoted string. No unescaping inside.
+		if s[0] == '"' || s[0] == '\'' {
+			quote := s[0]
+			s = s[1:]
+			i := 0
+			for i < len(s) && s[i] != quote {
+				i++
+			}
+			if i >= len(s) {
+				return nil, fmt.Errorf("unterminated %c string", quote)
+			}
+			f = append(f, s[:i])
+			s = s[i+1:]
+			continue
+		}
+		i := 0
+		for i < len(s) && !isSpaceByte(s[i]) {
+			i++
+		}
+		f = append(f, s[:i])
+		s = s[i:]
+	}
+	return f, nil
+}
diff --git a/libgo/go/cmd/go/test.go b/libgo/go/cmd/go/internal/test/test.go
similarity index 71%
rename from libgo/go/cmd/go/test.go
rename to libgo/go/cmd/go/internal/test/test.go
index 12990fe..c1e66f9 100644
--- a/libgo/go/cmd/go/test.go
+++ b/libgo/go/cmd/go/internal/test/test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package test
 
 import (
 	"bytes"
@@ -25,16 +25,22 @@
 	"time"
 	"unicode"
 	"unicode/utf8"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/str"
+	"cmd/go/internal/work"
 )
 
 // Break init loop.
 func init() {
-	cmdTest.Run = runTest
+	CmdTest.Run = runTest
 }
 
 const testUsage = "test [build/test flags] [packages] [build/test flags & test binary flags]"
 
-var cmdTest = &Command{
+var CmdTest = &base.Command{
 	CustomFlags: true,
 	UsageLine:   testUsage,
 	Short:       "test packages",
@@ -53,7 +59,7 @@
 the file pattern "*_test.go".
 Files whose names begin with "_" (including "_test.go") or "." are ignored.
 These additional files can contain test functions, benchmark functions, and
-example functions.  See 'go help testfunc' for more.
+example functions. See 'go help testfunc' for more.
 Each listed package causes the execution of a separate test binary.
 
 Test files that declare a package with the suffix "_test" will be compiled as a
@@ -62,7 +68,7 @@
 The go tool will ignore a directory named "testdata", making it available
 to hold ancillary data needed by the tests.
 
-By default, go test needs no arguments.  It compiles and tests the package
+By default, go test needs no arguments. It compiles and tests the package
 with source in the current directory, including tests, and runs the tests.
 
 The package is built in a temporary directory so it does not interfere with the
@@ -107,7 +113,15 @@
 flags are also accessible by 'go test'.
 `
 
-var helpTestflag = &Command{
+// Usage prints the usage message for 'go test -h' and exits.
+func Usage() {
+	os.Stderr.WriteString(testUsage + "\n\n" +
+		strings.TrimSpace(testFlag1) + "\n\n\t" +
+		strings.TrimSpace(testFlag2) + "\n")
+	os.Exit(2)
+}
+
+var HelpTestflag = &base.Command{
 	UsageLine: "testflag",
 	Short:     "description of testing flags",
 	Long: `
@@ -116,7 +130,7 @@
 
 Several of the flags control profiling and write an execution profile
 suitable for "go tool pprof"; run "go tool pprof -h" for more
-information.  The --alloc_space, --alloc_objects, and --show_bytes
+information. The --alloc_space, --alloc_objects, and --show_bytes
 options of pprof control how the information is presented.
 
 The following flags are recognized by the 'go test' command and
@@ -128,12 +142,17 @@
 
 const testFlag2 = `
 	-bench regexp
-	    Run (sub)benchmarks matching a regular expression.
-	    The given regular expression is split into smaller ones by
-	    top-level '/', where each must match the corresponding part of a
-	    benchmark's identifier.
-	    By default, no benchmarks run. To run all benchmarks,
-	    use '-bench .' or '-bench=.'.
+	    Run only those benchmarks matching a regular expression.
+	    By default, no benchmarks are run. 
+	    To run all benchmarks, use '-bench .' or '-bench=.'.
+	    The regular expression is split by unbracketed slash (/)
+	    characters into a sequence of regular expressions, and each
+	    part of a benchmark's identifier must match the corresponding
+	    element in the sequence, if any. Possible parents of matches
+	    are run with b.N=1 to identify sub-benchmarks. For example,
+	    given -bench=X/Y, top-level benchmarks matching X are run
+	    with b.N=1 to find any sub-benchmarks matching Y, which are
+	    then run in full.
 
 	-benchtime t
 	    Run enough iterations of each benchmark to take t, specified
@@ -147,6 +166,10 @@
 
 	-cover
 	    Enable coverage analysis.
+	    Note that because coverage works by annotating the source
+	    code before compilation, compilation and test failures with
+	    coverage enabled may report line numbers that don't correspond
+	    to the original sources.
 
 	-covermode set,count,atomic
 	    Set the mode for coverage analysis for the package[s]
@@ -167,9 +190,14 @@
 
 	-cpu 1,2,4
 	    Specify a list of GOMAXPROCS values for which the tests or
-	    benchmarks should be executed.  The default is the current value
+	    benchmarks should be executed. The default is the current value
 	    of GOMAXPROCS.
 
+	-list regexp
+	    List tests, benchmarks, or examples matching the regular expression.
+	    No tests, benchmarks or examples will be run. This will only
+	    list top-level tests. No subtest or subbenchmarks will be shown.
+
 	-parallel n
 	    Allow parallel execution of test functions that call t.Parallel.
 	    The value of this flag is the maximum number of tests to run
@@ -181,9 +209,13 @@
 
 	-run regexp
 	    Run only those tests and examples matching the regular expression.
-	    For tests the regular expression is split into smaller ones by
-	    top-level '/', where each must match the corresponding part of a
-	    test's identifier.
+	    For tests, the regular expression is split by unbracketed slash (/)
+	    characters into a sequence of regular expressions, and each part
+	    of a test's identifier must match the corresponding element in
+	    the sequence, if any. Note that possible parents of matches are
+	    run too, so that -run=X/Y matches and runs and reports the result
+	    of all tests matching X, even those without sub-tests matching Y,
+	    because it must run them to look for those sub-tests.
 
 	-short
 	    Tell long-running tests to shorten their run time.
@@ -191,8 +223,8 @@
 	    the Go tree can run a sanity check but not spend time running
 	    exhaustive tests.
 
-	-timeout t
-	    If a test runs longer than t, panic.
+	-timeout d
+	    If a test binary runs longer than duration d, panic.
 	    The default is 10 minutes (10m).
 
 	-v
@@ -215,7 +247,7 @@
 	    calling runtime.SetBlockProfileRate with n.
 	    See 'go doc runtime.SetBlockProfileRate'.
 	    The profiler aims to sample, on average, one blocking event every
-	    n nanoseconds the program spends blocked.  By default,
+	    n nanoseconds the program spends blocked. By default,
 	    if -test.blockprofile is set without this flag, all blocking events
 	    are recorded, equivalent to -test.blockprofilerate=1.
 
@@ -233,7 +265,7 @@
 
 	-memprofilerate n
 	    Enable more precise (and expensive) memory profiles by setting
-	    runtime.MemProfileRate.  See 'go doc runtime.MemProfileRate'.
+	    runtime.MemProfileRate. See 'go doc runtime.MemProfileRate'.
 	    To profile all memory allocations, use -test.memprofilerate=1
 	    and pass --alloc_space flag to the pprof tool.
 
@@ -312,7 +344,7 @@
 binary, instead of being interpreted as the package list.
 `
 
-var helpTestfunc = &Command{
+var HelpTestfunc = &base.Command{
 	UsageLine: "testfunc",
 	Short:     "description of testing functions",
 	Long: `
@@ -338,8 +370,8 @@
 "Output:" is compiled, executed, and expected to produce no output.
 
 Godoc displays the body of ExampleXXX to demonstrate the use
-of the function, constant, or variable XXX.  An example of a method M with
-receiver type T or *T is named ExampleT_M.  There may be multiple examples
+of the function, constant, or variable XXX. An example of a method M with
+receiver type T or *T is named ExampleT_M. There may be multiple examples
 for a given function, constant, or variable, distinguished by a trailing _xxx,
 where xxx is a suffix not beginning with an upper case letter.
 
@@ -374,18 +406,19 @@
 }
 
 var (
-	testC            bool       // -c flag
-	testCover        bool       // -cover flag
-	testCoverMode    string     // -covermode flag
-	testCoverPaths   []string   // -coverpkg flag
-	testCoverPkgs    []*Package // -coverpkg flag
-	testO            string     // -o flag
-	testProfile      bool       // some profiling flag
-	testNeedBinary   bool       // profile needs to keep binary around
-	testV            bool       // -v flag
-	testTimeout      string     // -timeout flag
+	testC            bool            // -c flag
+	testCover        bool            // -cover flag
+	testCoverMode    string          // -covermode flag
+	testCoverPaths   []string        // -coverpkg flag
+	testCoverPkgs    []*load.Package // -coverpkg flag
+	testO            string          // -o flag
+	testProfile      bool            // some profiling flag
+	testNeedBinary   bool            // profile needs to keep binary around
+	testV            bool            // -v flag
+	testTimeout      string          // -timeout flag
 	testArgs         []string
 	testBench        bool
+	testList         bool
 	testStreamOutput bool // show output as it is generated
 	testShowPass     bool // show passing output
 
@@ -399,27 +432,27 @@
 	"os": true,
 }
 
-func runTest(cmd *Command, args []string) {
+func runTest(cmd *base.Command, args []string) {
 	var pkgArgs []string
 	pkgArgs, testArgs = testFlags(args)
 
-	findExecCmd() // initialize cached result
+	work.FindExecCmd() // initialize cached result
 
-	instrumentInit()
-	buildModeInit()
-	pkgs := packagesForBuild(pkgArgs)
+	work.InstrumentInit()
+	work.BuildModeInit()
+	pkgs := load.PackagesForBuild(pkgArgs)
 	if len(pkgs) == 0 {
-		fatalf("no packages to test")
+		base.Fatalf("no packages to test")
 	}
 
 	if testC && len(pkgs) != 1 {
-		fatalf("cannot use -c flag with multiple packages")
+		base.Fatalf("cannot use -c flag with multiple packages")
 	}
 	if testO != "" && len(pkgs) != 1 {
-		fatalf("cannot use -o flag with multiple packages")
+		base.Fatalf("cannot use -o flag with multiple packages")
 	}
 	if testProfile && len(pkgs) != 1 {
-		fatalf("cannot use test profile flag with multiple packages")
+		base.Fatalf("cannot use test profile flag with multiple packages")
 	}
 
 	// If a test timeout was given and is parseable, set our kill timeout
@@ -433,7 +466,7 @@
 	// show passing test output (after buffering) with -v flag.
 	// must buffer because tests are running in parallel, and
 	// otherwise the output will get mixed.
-	testShowPass = testV
+	testShowPass = testV || testList
 
 	// stream test output (no buffering) when no package has
 	// been given on the command line (implicit current directory)
@@ -443,18 +476,18 @@
 	// In these cases, streaming the output produces the same result
 	// as not streaming, just more immediately.
 	testStreamOutput = len(pkgArgs) == 0 || testBench ||
-		(testShowPass && (len(pkgs) == 1 || buildP == 1))
+		(testShowPass && (len(pkgs) == 1 || cfg.BuildP == 1))
 
 	// For 'go test -i -o x.test', we want to build x.test. Imply -c to make the logic easier.
-	if buildI && testO != "" {
+	if cfg.BuildI && testO != "" {
 		testC = true
 	}
 
-	var b builder
-	b.init()
+	var b work.Builder
+	b.Init()
 
-	if buildI {
-		buildV = testV
+	if cfg.BuildI {
+		cfg.BuildV = testV
 
 		deps := make(map[string]bool)
 		for dep := range testMainDeps {
@@ -466,10 +499,10 @@
 			for _, path := range p.Imports {
 				deps[path] = true
 			}
-			for _, path := range p.vendored(p.TestImports) {
+			for _, path := range p.Vendored(p.TestImports) {
 				deps[path] = true
 			}
-			for _, path := range p.vendored(p.XTestImports) {
+			for _, path := range p.Vendored(p.XTestImports) {
 				deps[path] = true
 			}
 		}
@@ -478,7 +511,7 @@
 		if deps["C"] {
 			delete(deps, "C")
 			deps["runtime/cgo"] = true
-			if goos == runtime.GOOS && goarch == runtime.GOARCH && !buildRace && !buildMSan {
+			if cfg.Goos == runtime.GOOS && cfg.Goarch == runtime.GOARCH && !cfg.BuildRace && !cfg.BuildMSan {
 				deps["cmd/cgo"] = true
 			}
 		}
@@ -493,26 +526,26 @@
 		}
 		sort.Strings(all)
 
-		a := &action{}
-		for _, p := range packagesForBuild(all) {
-			if !reqStdPkgSrc && p.Standard {
+		a := &work.Action{}
+		for _, p := range load.PackagesForBuild(all) {
+			if cfg.BuildToolchainName == "gccgo" && p.Standard {
 				continue
 			}
-			a.deps = append(a.deps, b.action(modeInstall, modeInstall, p))
+			a.Deps = append(a.Deps, b.Action(work.ModeInstall, work.ModeInstall, p))
 		}
-		b.do(a)
-		if !testC || a.failed {
+		b.Do(a)
+		if !testC || a.Failed {
 			return
 		}
-		b.init()
+		b.Init()
 	}
 
-	var builds, runs, prints []*action
+	var builds, runs, prints []*work.Action
 
 	if testCoverPaths != nil {
 		// Load packages that were asked about for coverage.
 		// packagesForBuild exits if the packages cannot be loaded.
-		testCoverPkgs = packagesForBuild(testCoverPaths)
+		testCoverPkgs = load.PackagesForBuild(testCoverPaths)
 
 		// Warn about -coverpkg arguments that are not actually used.
 		used := make(map[string]bool)
@@ -536,13 +569,13 @@
 			}
 			p.Stale = true // rebuild
 			p.StaleReason = "rebuild for coverage"
-			p.fake = true // do not warn about rebuild
-			p.coverMode = testCoverMode
+			p.Internal.Fake = true // do not warn about rebuild
+			p.Internal.CoverMode = testCoverMode
 			var coverFiles []string
 			coverFiles = append(coverFiles, p.GoFiles...)
 			coverFiles = append(coverFiles, p.CgoFiles...)
 			coverFiles = append(coverFiles, p.TestGoFiles...)
-			p.coverVars = declareCoverVars(p.ImportPath, coverFiles...)
+			p.Internal.CoverVars = declareCoverVars(p.ImportPath, coverFiles...)
 		}
 	}
 
@@ -552,7 +585,8 @@
 		if testCover && testCoverMode == "atomic" {
 			ensureImport(p, "sync/atomic")
 		}
-		buildTest, runTest, printTest, err := b.test(p)
+
+		buildTest, runTest, printTest, err := builderTest(&b, p)
 		if err != nil {
 			str := err.Error()
 			if strings.HasPrefix(str, "\n") {
@@ -561,9 +595,9 @@
 			failed := fmt.Sprintf("FAIL\t%s [setup failed]\n", p.ImportPath)
 
 			if p.ImportPath != "" {
-				errorf("# %s\n%s\n%s", p.ImportPath, str, failed)
+				base.Errorf("# %s\n%s\n%s", p.ImportPath, str, failed)
 			} else {
-				errorf("%s\n%s", str, failed)
+				base.Errorf("%s\n%s", str, failed)
 			}
 			continue
 		}
@@ -573,13 +607,13 @@
 	}
 
 	// Ultimately the goal is to print the output.
-	root := &action{deps: prints}
+	root := &work.Action{Deps: prints}
 
 	// Force the printing of results to happen in order,
 	// one at a time.
 	for i, a := range prints {
 		if i > 0 {
-			a.deps = append(a.deps, prints[i-1])
+			a.Deps = append(a.Deps, prints[i-1])
 		}
 	}
 
@@ -589,40 +623,40 @@
 		// Later runs must wait for the previous run's print.
 		for i, run := range runs {
 			if i == 0 {
-				run.deps = append(run.deps, builds...)
+				run.Deps = append(run.Deps, builds...)
 			} else {
-				run.deps = append(run.deps, prints[i-1])
+				run.Deps = append(run.Deps, prints[i-1])
 			}
 		}
 	}
 
 	// If we are building any out-of-date packages other
 	// than those under test, warn.
-	okBuild := map[*Package]bool{}
+	okBuild := map[*load.Package]bool{}
 	for _, p := range pkgs {
 		okBuild[p] = true
 	}
 	warned := false
-	for _, a := range actionList(root) {
-		if a.p == nil || okBuild[a.p] {
+	for _, a := range work.ActionList(root) {
+		if a.Package == nil || okBuild[a.Package] {
 			continue
 		}
-		okBuild[a.p] = true // warn at most once
+		okBuild[a.Package] = true // warn at most once
 
 		// Don't warn about packages being rebuilt because of
 		// things like coverage analysis.
-		for _, p1 := range a.p.imports {
-			if p1.fake {
-				a.p.fake = true
+		for _, p1 := range a.Package.Internal.Imports {
+			if p1.Internal.Fake {
+				a.Package.Internal.Fake = true
 			}
 		}
 
-		if a.f != nil && !okBuild[a.p] && !a.p.fake && !a.p.local {
+		if a.Func != nil && !okBuild[a.Package] && !a.Package.Internal.Fake && !a.Package.Internal.Local {
 			if !warned {
 				fmt.Fprintf(os.Stderr, "warning: building out-of-date packages:\n")
 				warned = true
 			}
-			fmt.Fprintf(os.Stderr, "\t%s\n", a.p.ImportPath)
+			fmt.Fprintf(os.Stderr, "\t%s\n", a.Package.ImportPath)
 		}
 	}
 	if warned {
@@ -631,42 +665,33 @@
 			args = " " + args
 		}
 		extraOpts := ""
-		if buildRace {
+		if cfg.BuildRace {
 			extraOpts = "-race "
 		}
-		if buildMSan {
+		if cfg.BuildMSan {
 			extraOpts = "-msan "
 		}
 		fmt.Fprintf(os.Stderr, "installing these packages with 'go test %s-i%s' will speed future tests.\n\n", extraOpts, args)
 	}
 
-	b.do(root)
+	b.Do(root)
 }
 
-// ensures that package p imports the named package.
-func ensureImport(p *Package, pkg string) {
-	for _, d := range p.deps {
+// ensures that package p imports the named package
+func ensureImport(p *load.Package, pkg string) {
+	for _, d := range p.Internal.Deps {
 		if d.Name == pkg {
 			return
 		}
 	}
 
-	a := loadPackage(pkg, &importStack{})
+	a := load.LoadPackage(pkg, &load.ImportStack{})
 	if a.Error != nil {
-		fatalf("load %s: %v", pkg, a.Error)
+		base.Fatalf("load %s: %v", pkg, a.Error)
 	}
-	computeStale(a)
+	load.ComputeStale(a)
 
-	p.imports = append(p.imports, a)
-}
-
-func contains(x []string, s string) bool {
-	for _, t := range x {
-		if t == s {
-			return true
-		}
-	}
-	return false
+	p.Internal.Imports = append(p.Internal.Imports, a)
 }
 
 var windowsBadWords = []string{
@@ -676,11 +701,11 @@
 	"update",
 }
 
-func (b *builder) test(p *Package) (buildAction, runAction, printAction *action, err error) {
+func builderTest(b *work.Builder, p *load.Package) (buildAction, runAction, printAction *work.Action, err error) {
 	if len(p.TestGoFiles)+len(p.XTestGoFiles) == 0 {
-		build := b.action(modeBuild, modeBuild, p)
-		run := &action{p: p, deps: []*action{build}}
-		print := &action{f: (*builder).notest, p: p, deps: []*action{run}}
+		build := b.Action(work.ModeBuild, work.ModeBuild, p)
+		run := &work.Action{Package: p, Deps: []*work.Action{build}}
+		print := &work.Action{Func: builderNoTest, Package: p, Deps: []*work.Action{run}}
 		return build, run, print, nil
 	}
 
@@ -688,14 +713,14 @@
 	//	ptest - package + test files
 	//	pxtest - package of external test files
 	//	pmain - pkg.test binary
-	var ptest, pxtest, pmain *Package
+	var ptest, pxtest, pmain *load.Package
 
-	var imports, ximports []*Package
-	var stk importStack
-	stk.push(p.ImportPath + " (test)")
+	var imports, ximports []*load.Package
+	var stk load.ImportStack
+	stk.Push(p.ImportPath + " (test)")
 	for i, path := range p.TestImports {
-		p1 := loadImport(path, p.Dir, p, &stk, p.build.TestImportPos[path], useVendor)
-		if !reqStdPkgSrc && p1.Standard {
+		p1 := load.LoadImport(path, p.Dir, p, &stk, p.Internal.Build.TestImportPos[path], load.UseVendor)
+		if cfg.BuildToolchainName == "gccgo" && p1.Standard {
 			continue
 		}
 		if p1.Error != nil {
@@ -706,26 +731,26 @@
 			err.Pos = "" // show full import stack
 			return nil, nil, nil, err
 		}
-		if contains(p1.Deps, p.ImportPath) || p1.ImportPath == p.ImportPath {
+		if str.Contains(p1.Deps, p.ImportPath) || p1.ImportPath == p.ImportPath {
 			// Same error that loadPackage returns (via reusePackage) in pkg.go.
 			// Can't change that code, because that code is only for loading the
 			// non-test copy of a package.
-			err := &PackageError{
+			err := &load.PackageError{
 				ImportStack:   testImportStack(stk[0], p1, p.ImportPath),
 				Err:           "import cycle not allowed in test",
-				isImportCycle: true,
+				IsImportCycle: true,
 			}
 			return nil, nil, nil, err
 		}
 		p.TestImports[i] = p1.ImportPath
 		imports = append(imports, p1)
 	}
-	stk.pop()
-	stk.push(p.ImportPath + "_test")
+	stk.Pop()
+	stk.Push(p.ImportPath + "_test")
 	pxtestNeedsPtest := false
 	for i, path := range p.XTestImports {
-		p1 := loadImport(path, p.Dir, p, &stk, p.build.XTestImportPos[path], useVendor)
-		if !reqStdPkgSrc && p1.Standard {
+		p1 := load.LoadImport(path, p.Dir, p, &stk, p.Internal.Build.XTestImportPos[path], load.UseVendor)
+		if cfg.BuildToolchainName == "gccgo" && p1.Standard {
 			continue
 		}
 		if p1.Error != nil {
@@ -743,7 +768,7 @@
 		}
 		p.XTestImports[i] = p1.ImportPath
 	}
-	stk.pop()
+	stk.Pop()
 
 	// Use last element of import path, not package name.
 	// They differ when package name is "main".
@@ -771,12 +796,12 @@
 	// $WORK/unicode/utf8/_test/unicode/utf8.a.
 	// We write the external test package archive to
 	// $WORK/unicode/utf8/_test/unicode/utf8_test.a.
-	testDir := filepath.Join(b.work, filepath.FromSlash(p.ImportPath+"/_test"))
-	ptestObj := buildToolchain.pkgpath(testDir, p)
+	testDir := filepath.Join(b.WorkDir, filepath.FromSlash(p.ImportPath+"/_test"))
+	ptestObj := work.BuildToolchain.Pkgpath(testDir, p)
 
 	// Create the directory for the .a files.
 	ptestDir, _ := filepath.Split(ptestObj)
-	if err := b.mkdir(ptestDir); err != nil {
+	if err := b.Mkdir(ptestDir); err != nil {
 		return nil, nil, nil, err
 	}
 
@@ -788,36 +813,36 @@
 
 	// Test package.
 	if len(p.TestGoFiles) > 0 || localCover || p.Name == "main" {
-		ptest = new(Package)
+		ptest = new(load.Package)
 		*ptest = *p
 		ptest.GoFiles = nil
 		ptest.GoFiles = append(ptest.GoFiles, p.GoFiles...)
 		ptest.GoFiles = append(ptest.GoFiles, p.TestGoFiles...)
-		ptest.target = ""
-		ptest.Imports = stringList(p.Imports, p.TestImports)
-		ptest.imports = append(append([]*Package{}, p.imports...), imports...)
-		ptest.pkgdir = testDir
-		ptest.fake = true
-		ptest.forceLibrary = true
+		ptest.Internal.Target = ""
+		ptest.Imports = str.StringList(p.Imports, p.TestImports)
+		ptest.Internal.Imports = append(append([]*load.Package{}, p.Internal.Imports...), imports...)
+		ptest.Internal.Pkgdir = testDir
+		ptest.Internal.Fake = true
+		ptest.Internal.ForceLibrary = true
 		ptest.Stale = true
 		ptest.StaleReason = "rebuild for test"
-		ptest.build = new(build.Package)
-		*ptest.build = *p.build
+		ptest.Internal.Build = new(build.Package)
+		*ptest.Internal.Build = *p.Internal.Build
 		m := map[string][]token.Position{}
-		for k, v := range p.build.ImportPos {
+		for k, v := range p.Internal.Build.ImportPos {
 			m[k] = append(m[k], v...)
 		}
-		for k, v := range p.build.TestImportPos {
+		for k, v := range p.Internal.Build.TestImportPos {
 			m[k] = append(m[k], v...)
 		}
-		ptest.build.ImportPos = m
+		ptest.Internal.Build.ImportPos = m
 
 		if localCover {
-			ptest.coverMode = testCoverMode
+			ptest.Internal.CoverMode = testCoverMode
 			var coverFiles []string
 			coverFiles = append(coverFiles, ptest.GoFiles...)
 			coverFiles = append(coverFiles, ptest.CgoFiles...)
-			ptest.coverVars = declareCoverVars(ptest.ImportPath, coverFiles...)
+			ptest.Internal.CoverVars = declareCoverVars(ptest.ImportPath, coverFiles...)
 		}
 	} else {
 		ptest = p
@@ -825,69 +850,77 @@
 
 	// External test package.
 	if len(p.XTestGoFiles) > 0 {
-		pxtest = &Package{
-			Name:        p.Name + "_test",
-			ImportPath:  p.ImportPath + "_test",
-			localPrefix: p.localPrefix,
-			Root:        p.Root,
-			Dir:         p.Dir,
-			GoFiles:     p.XTestGoFiles,
-			Imports:     p.XTestImports,
-			build: &build.Package{
-				ImportPos: p.build.XTestImportPos,
+		pxtest = &load.Package{
+			PackagePublic: load.PackagePublic{
+				Name:       p.Name + "_test",
+				ImportPath: p.ImportPath + "_test",
+				Root:       p.Root,
+				Dir:        p.Dir,
+				GoFiles:    p.XTestGoFiles,
+				Imports:    p.XTestImports,
+				Stale:      true,
 			},
-			imports:  ximports,
-			pkgdir:   testDir,
-			fake:     true,
-			external: true,
-			Stale:    true,
+			Internal: load.PackageInternal{
+				LocalPrefix: p.Internal.LocalPrefix,
+				Build: &build.Package{
+					ImportPos: p.Internal.Build.XTestImportPos,
+				},
+				Imports:  ximports,
+				Pkgdir:   testDir,
+				Fake:     true,
+				External: true,
+			},
 		}
 		if pxtestNeedsPtest {
-			pxtest.imports = append(pxtest.imports, ptest)
+			pxtest.Internal.Imports = append(pxtest.Internal.Imports, ptest)
 		}
 	}
 
 	// Action for building pkg.test.
-	pmain = &Package{
-		Name:       "main",
-		Dir:        testDir,
-		GoFiles:    []string{"_testmain.go"},
-		ImportPath: "testmain",
-		Root:       p.Root,
-		build:      &build.Package{Name: "main"},
-		pkgdir:     testDir,
-		fake:       true,
-		Stale:      true,
-		omitDWARF:  !testC && !testNeedBinary,
+	pmain = &load.Package{
+		PackagePublic: load.PackagePublic{
+			Name:       "main",
+			Dir:        testDir,
+			GoFiles:    []string{"_testmain.go"},
+			ImportPath: "testmain",
+			Root:       p.Root,
+			Stale:      true,
+		},
+		Internal: load.PackageInternal{
+			Build:     &build.Package{Name: "main"},
+			Pkgdir:    testDir,
+			Fake:      true,
+			OmitDebug: !testC && !testNeedBinary,
+		},
 	}
 
 	// The generated main also imports testing, regexp, and os.
-	stk.push("testmain")
+	stk.Push("testmain")
 	for dep := range testMainDeps {
 		if dep == ptest.ImportPath {
-			pmain.imports = append(pmain.imports, ptest)
+			pmain.Internal.Imports = append(pmain.Internal.Imports, ptest)
 		} else {
-			p1 := loadImport(dep, "", nil, &stk, nil, 0)
-			if !reqStdPkgSrc && p1.Standard {
+			p1 := load.LoadImport(dep, "", nil, &stk, nil, 0)
+			if cfg.BuildToolchainName == "gccgo" && p1.Standard {
 				continue
 			}
 			if p1.Error != nil {
 				return nil, nil, nil, p1.Error
 			}
-			pmain.imports = append(pmain.imports, p1)
+			pmain.Internal.Imports = append(pmain.Internal.Imports, p1)
 		}
 	}
 
 	if testCoverPkgs != nil {
 		// Add imports, but avoid duplicates.
-		seen := map[*Package]bool{p: true, ptest: true}
-		for _, p1 := range pmain.imports {
+		seen := map[*load.Package]bool{p: true, ptest: true}
+		for _, p1 := range pmain.Internal.Imports {
 			seen[p1] = true
 		}
 		for _, p1 := range testCoverPkgs {
 			if !seen[p1] {
 				seen[p1] = true
-				pmain.imports = append(pmain.imports, p1)
+				pmain.Internal.Imports = append(pmain.Internal.Imports, p1)
 			}
 		}
 	}
@@ -901,11 +934,11 @@
 		return nil, nil, nil, err
 	}
 	if len(ptest.GoFiles)+len(ptest.CgoFiles) > 0 {
-		pmain.imports = append(pmain.imports, ptest)
+		pmain.Internal.Imports = append(pmain.Internal.Imports, ptest)
 		t.ImportTest = true
 	}
 	if pxtest != nil {
-		pmain.imports = append(pmain.imports, pxtest)
+		pmain.Internal.Imports = append(pmain.Internal.Imports, pxtest)
 		t.ImportXtest = true
 	}
 
@@ -925,23 +958,19 @@
 		recompileForTest(pmain, p, ptest, testDir)
 	}
 
-	if buildContext.GOOS == "darwin" {
-		if buildContext.GOARCH == "arm" || buildContext.GOARCH == "arm64" {
-			t.IsIOS = true
-			t.NeedOS = true
-		}
-	}
-	if t.TestMain == nil {
-		t.NeedOS = true
-	}
-
-	for _, cp := range pmain.imports {
-		if len(cp.coverVars) > 0 {
-			t.Cover = append(t.Cover, coverInfo{cp, cp.coverVars})
+	if cfg.BuildContext.GOOS == "darwin" {
+		if cfg.BuildContext.GOARCH == "arm" || cfg.BuildContext.GOARCH == "arm64" {
+			t.NeedCgo = true
 		}
 	}
 
-	if !buildN {
+	for _, cp := range pmain.Internal.Imports {
+		if len(cp.Internal.CoverVars) > 0 {
+			t.Cover = append(t.Cover, coverInfo{cp, cp.Internal.CoverVars})
+		}
+	}
+
+	if !cfg.BuildN {
 		// writeTestmain writes _testmain.go. This must happen after recompileForTest,
 		// because recompileForTest modifies XXX.
 		if err := writeTestmain(filepath.Join(testDir, "_testmain.go"), t); err != nil {
@@ -949,28 +978,28 @@
 		}
 	}
 
-	computeStale(pmain)
+	load.ComputeStale(pmain)
 
 	if ptest != p {
-		a := b.action(modeBuild, modeBuild, ptest)
-		a.objdir = testDir + string(filepath.Separator) + "_obj_test" + string(filepath.Separator)
-		a.objpkg = ptestObj
-		a.target = ptestObj
-		a.link = false
+		a := b.Action(work.ModeBuild, work.ModeBuild, ptest)
+		a.Objdir = testDir + string(filepath.Separator) + "_obj_test" + string(filepath.Separator)
+		a.Objpkg = ptestObj
+		a.Target = ptestObj
+		a.Link = false
 	}
 
 	if pxtest != nil {
-		a := b.action(modeBuild, modeBuild, pxtest)
-		a.objdir = testDir + string(filepath.Separator) + "_obj_xtest" + string(filepath.Separator)
-		a.objpkg = buildToolchain.pkgpath(testDir, pxtest)
-		a.target = a.objpkg
+		a := b.Action(work.ModeBuild, work.ModeBuild, pxtest)
+		a.Objdir = testDir + string(filepath.Separator) + "_obj_xtest" + string(filepath.Separator)
+		a.Objpkg = work.BuildToolchain.Pkgpath(testDir, pxtest)
+		a.Target = a.Objpkg
 	}
 
-	a := b.action(modeBuild, modeBuild, pmain)
-	a.objdir = testDir + string(filepath.Separator)
-	a.objpkg = filepath.Join(testDir, "main.a")
-	a.target = filepath.Join(testDir, testBinary) + exeSuffix
-	if goos == "windows" {
+	a := b.Action(work.ModeBuild, work.ModeBuild, pmain)
+	a.Objdir = testDir + string(filepath.Separator)
+	a.Objpkg = filepath.Join(testDir, "main.a")
+	a.Target = filepath.Join(testDir, testBinary) + cfg.ExeSuffix
+	if cfg.Goos == "windows" {
 		// There are many reserved words on Windows that,
 		// if used in the name of an executable, cause Windows
 		// to try to ask for extra permissions.
@@ -995,7 +1024,7 @@
 		// we could just do this always on Windows.
 		for _, bad := range windowsBadWords {
 			if strings.Contains(testBinary, bad) {
-				a.target = filepath.Join(testDir, "test.test") + exeSuffix
+				a.Target = filepath.Join(testDir, "test.test") + cfg.ExeSuffix
 				break
 			}
 		}
@@ -1004,52 +1033,52 @@
 
 	if testC || testNeedBinary {
 		// -c or profiling flag: create action to copy binary to ./test.out.
-		target := filepath.Join(cwd, testBinary+exeSuffix)
+		target := filepath.Join(base.Cwd, testBinary+cfg.ExeSuffix)
 		if testO != "" {
 			target = testO
 			if !filepath.IsAbs(target) {
-				target = filepath.Join(cwd, target)
+				target = filepath.Join(base.Cwd, target)
 			}
 		}
-		buildAction = &action{
-			f:      (*builder).install,
-			deps:   []*action{buildAction},
-			p:      pmain,
-			target: target,
+		buildAction = &work.Action{
+			Func:    work.BuildInstallFunc,
+			Deps:    []*work.Action{buildAction},
+			Package: pmain,
+			Target:  target,
 		}
 		runAction = buildAction // make sure runAction != nil even if not running test
 	}
 	if testC {
-		printAction = &action{p: p, deps: []*action{runAction}} // nop
+		printAction = &work.Action{Package: p, Deps: []*work.Action{runAction}} // nop
 	} else {
 		// run test
-		runAction = &action{
-			f:          (*builder).runTest,
-			deps:       []*action{buildAction},
-			p:          p,
-			ignoreFail: true,
+		runAction = &work.Action{
+			Func:       builderRunTest,
+			Deps:       []*work.Action{buildAction},
+			Package:    p,
+			IgnoreFail: true,
 		}
-		cleanAction := &action{
-			f:    (*builder).cleanTest,
-			deps: []*action{runAction},
-			p:    p,
+		cleanAction := &work.Action{
+			Func:    builderCleanTest,
+			Deps:    []*work.Action{runAction},
+			Package: p,
 		}
-		printAction = &action{
-			f:    (*builder).printTest,
-			deps: []*action{cleanAction},
-			p:    p,
+		printAction = &work.Action{
+			Func:    builderPrintTest,
+			Deps:    []*work.Action{cleanAction},
+			Package: p,
 		}
 	}
 
 	return buildAction, runAction, printAction, nil
 }
 
-func testImportStack(top string, p *Package, target string) []string {
+func testImportStack(top string, p *load.Package, target string) []string {
 	stk := []string{top, p.ImportPath}
 Search:
 	for p.ImportPath != target {
-		for _, p1 := range p.imports {
-			if p1.ImportPath == target || contains(p1.Deps, target) {
+		for _, p1 := range p.Internal.Imports {
+			if p1.ImportPath == target || str.Contains(p1.Deps, target) {
 				stk = append(stk, p1.ImportPath)
 				p = p1
 				continue Search
@@ -1062,12 +1091,12 @@
 	return stk
 }
 
-func recompileForTest(pmain, preal, ptest *Package, testDir string) {
+func recompileForTest(pmain, preal, ptest *load.Package, testDir string) {
 	// The "test copy" of preal is ptest.
 	// For each package that depends on preal, make a "test copy"
 	// that depends on ptest. And so on, up the dependency tree.
-	testCopy := map[*Package]*Package{preal: ptest}
-	for _, p := range packageList([]*Package{pmain}) {
+	testCopy := map[*load.Package]*load.Package{preal: ptest}
+	for _, p := range load.PackageList([]*load.Package{pmain}) {
 		// Copy on write.
 		didSplit := false
 		split := func() {
@@ -1075,32 +1104,32 @@
 				return
 			}
 			didSplit = true
-			if p.pkgdir != testDir {
-				p1 := new(Package)
+			if p.Internal.Pkgdir != testDir {
+				p1 := new(load.Package)
 				testCopy[p] = p1
 				*p1 = *p
-				p1.imports = make([]*Package, len(p.imports))
-				copy(p1.imports, p.imports)
+				p1.Internal.Imports = make([]*load.Package, len(p.Internal.Imports))
+				copy(p1.Internal.Imports, p.Internal.Imports)
 				p = p1
-				p.pkgdir = testDir
-				p.target = ""
-				p.fake = true
+				p.Internal.Pkgdir = testDir
+				p.Internal.Target = ""
+				p.Internal.Fake = true
 				p.Stale = true
 				p.StaleReason = "depends on package being tested"
 			}
 		}
 
-		// Update p.deps and p.imports to use at test copies.
-		for i, dep := range p.deps {
+		// Update p.Deps and p.Internal.Imports to use at test copies.
+		for i, dep := range p.Internal.Deps {
 			if p1 := testCopy[dep]; p1 != nil && p1 != dep {
 				split()
-				p.deps[i] = p1
+				p.Internal.Deps[i] = p1
 			}
 		}
-		for i, imp := range p.imports {
+		for i, imp := range p.Internal.Imports {
 			if p1 := testCopy[imp]; p1 != nil && p1 != imp {
 				split()
-				p.imports[i] = p1
+				p.Internal.Imports[i] = p1
 			}
 		}
 	}
@@ -1117,13 +1146,13 @@
 
 // declareCoverVars attaches the required cover variables names
 // to the files, to be used when annotating the files.
-func declareCoverVars(importPath string, files ...string) map[string]*CoverVar {
-	coverVars := make(map[string]*CoverVar)
+func declareCoverVars(importPath string, files ...string) map[string]*load.CoverVar {
+	coverVars := make(map[string]*load.CoverVar)
 	for _, file := range files {
 		if isTestFile(file) {
 			continue
 		}
-		coverVars[file] = &CoverVar{
+		coverVars[file] = &load.CoverVar{
 			File: filepath.Join(importPath, file),
 			Var:  fmt.Sprintf("GoCover_%d", coverIndex),
 		}
@@ -1134,29 +1163,29 @@
 
 var noTestsToRun = []byte("\ntesting: warning: no tests to run\n")
 
-// runTest is the action for running a test binary.
-func (b *builder) runTest(a *action) error {
-	args := stringList(findExecCmd(), a.deps[0].target, testArgs)
-	a.testOutput = new(bytes.Buffer)
+// builderRunTest is the action for running a test binary.
+func builderRunTest(b *work.Builder, a *work.Action) error {
+	args := str.StringList(work.FindExecCmd(), a.Deps[0].Target, testArgs)
+	a.TestOutput = new(bytes.Buffer)
 
-	if buildN || buildX {
-		b.showcmd("", "%s", strings.Join(args, " "))
-		if buildN {
+	if cfg.BuildN || cfg.BuildX {
+		b.Showcmd("", "%s", strings.Join(args, " "))
+		if cfg.BuildN {
 			return nil
 		}
 	}
 
-	if a.failed {
+	if a.Failed {
 		// We were unable to build the binary.
-		a.failed = false
-		fmt.Fprintf(a.testOutput, "FAIL\t%s [build failed]\n", a.p.ImportPath)
-		setExitStatus(1)
+		a.Failed = false
+		fmt.Fprintf(a.TestOutput, "FAIL\t%s [build failed]\n", a.Package.ImportPath)
+		base.SetExitStatus(1)
 		return nil
 	}
 
 	cmd := exec.Command(args[0], args[1:]...)
-	cmd.Dir = a.p.Dir
-	cmd.Env = envForDir(cmd.Dir, origEnv)
+	cmd.Dir = a.Package.Dir
+	cmd.Env = base.EnvForDir(cmd.Dir, cfg.OrigEnv)
 	var buf bytes.Buffer
 	if testStreamOutput {
 		cmd.Stdout = os.Stdout
@@ -1168,7 +1197,7 @@
 
 	// If there are any local SWIG dependencies, we want to load
 	// the shared library from the build directory.
-	if a.p.usesSwig() {
+	if a.Package.UsesSwig() {
 		env := cmd.Env
 		found := false
 		prefix := "LD_LIBRARY_PATH="
@@ -1193,7 +1222,7 @@
 	// running.
 	if err == nil {
 		tick := time.NewTimer(testKillTimeout)
-		startSigHandlers()
+		base.StartSigHandlers()
 		done := make(chan error)
 		go func() {
 			done <- cmd.Wait()
@@ -1203,14 +1232,14 @@
 		case err = <-done:
 			// ok
 		case <-tick.C:
-			if signalTrace != nil {
+			if base.SignalTrace != nil {
 				// Send a quit signal in the hope that the program will print
 				// a stack trace and exit. Give it five seconds before resorting
 				// to Kill.
-				cmd.Process.Signal(signalTrace)
+				cmd.Process.Signal(base.SignalTrace)
 				select {
 				case err = <-done:
-					fmt.Fprintf(&buf, "*** Test killed with %v: ran too long (%v).\n", signalTrace, testKillTimeout)
+					fmt.Fprintf(&buf, "*** Test killed with %v: ran too long (%v).\n", base.SignalTrace, testKillTimeout)
 					break Outer
 				case <-time.After(5 * time.Second):
 				}
@@ -1226,23 +1255,23 @@
 	if err == nil {
 		norun := ""
 		if testShowPass {
-			a.testOutput.Write(out)
+			a.TestOutput.Write(out)
 		}
 		if bytes.HasPrefix(out, noTestsToRun[1:]) || bytes.Contains(out, noTestsToRun) {
 			norun = " [no tests to run]"
 		}
-		fmt.Fprintf(a.testOutput, "ok  \t%s\t%s%s%s\n", a.p.ImportPath, t, coveragePercentage(out), norun)
+		fmt.Fprintf(a.TestOutput, "ok  \t%s\t%s%s%s\n", a.Package.ImportPath, t, coveragePercentage(out), norun)
 		return nil
 	}
 
-	setExitStatus(1)
+	base.SetExitStatus(1)
 	if len(out) > 0 {
-		a.testOutput.Write(out)
+		a.TestOutput.Write(out)
 		// assume printing the test binary's exit status is superfluous
 	} else {
-		fmt.Fprintf(a.testOutput, "%s\n", err)
+		fmt.Fprintf(a.TestOutput, "%s\n", err)
 	}
-	fmt.Fprintf(a.testOutput, "FAIL\t%s\t%s\n", a.p.ImportPath, t)
+	fmt.Fprintf(a.TestOutput, "FAIL\t%s\t%s\n", a.Package.ImportPath, t)
 
 	return nil
 }
@@ -1266,29 +1295,29 @@
 	return fmt.Sprintf("\tcoverage: %s", matches[1])
 }
 
-// cleanTest is the action for cleaning up after a test.
-func (b *builder) cleanTest(a *action) error {
-	if buildWork {
+// builderCleanTest is the action for cleaning up after a test.
+func builderCleanTest(b *work.Builder, a *work.Action) error {
+	if cfg.BuildWork {
 		return nil
 	}
-	run := a.deps[0]
-	testDir := filepath.Join(b.work, filepath.FromSlash(run.p.ImportPath+"/_test"))
+	run := a.Deps[0]
+	testDir := filepath.Join(b.WorkDir, filepath.FromSlash(run.Package.ImportPath+"/_test"))
 	os.RemoveAll(testDir)
 	return nil
 }
 
-// printTest is the action for printing a test result.
-func (b *builder) printTest(a *action) error {
-	clean := a.deps[0]
-	run := clean.deps[0]
-	os.Stdout.Write(run.testOutput.Bytes())
-	run.testOutput = nil
+// builderPrintTest is the action for printing a test result.
+func builderPrintTest(b *work.Builder, a *work.Action) error {
+	clean := a.Deps[0]
+	run := clean.Deps[0]
+	os.Stdout.Write(run.TestOutput.Bytes())
+	run.TestOutput = nil
 	return nil
 }
 
-// notest is the action for testing a package with no test files.
-func (b *builder) notest(a *action) error {
-	fmt.Printf("?   \t%s\t[no test files]\n", a.p.ImportPath)
+// builderNoTest is the action for testing a package with no test files.
+func builderNoTest(b *work.Builder, a *work.Action) error {
+	fmt.Printf("?   \t%s\t[no test files]\n", a.Package.ImportPath)
 	return nil
 }
 
@@ -1333,12 +1362,12 @@
 }
 
 type coverInfo struct {
-	Package *Package
-	Vars    map[string]*CoverVar
+	Package *load.Package
+	Vars    map[string]*load.CoverVar
 }
 
 // loadTestFuncs returns the testFuncs describing the tests that will be run.
-func loadTestFuncs(ptest *Package) (*testFuncs, error) {
+func loadTestFuncs(ptest *load.Package) (*testFuncs, error) {
 	t := &testFuncs{
 		Package: ptest,
 	}
@@ -1375,13 +1404,12 @@
 	Benchmarks  []testFunc
 	Examples    []testFunc
 	TestMain    *testFunc
-	Package     *Package
+	Package     *load.Package
 	ImportTest  bool
 	NeedTest    bool
 	ImportXtest bool
 	NeedXtest   bool
-	NeedOS      bool
-	IsIOS       bool
+	NeedCgo     bool
 	Cover       []coverInfo
 }
 
@@ -1393,6 +1421,19 @@
 	return testCover
 }
 
+// ImportPath returns the import path of the package being tested, if it is within GOPATH.
+// This is printed by the testing package when running benchmarks.
+func (t *testFuncs) ImportPath() string {
+	pkg := t.Package.ImportPath
+	if strings.HasPrefix(pkg, "_/") {
+		return ""
+	}
+	if pkg == "command-line-arguments" {
+		return ""
+	}
+	return pkg
+}
+
 // Covered returns a string describing which packages are being tested for coverage.
 // If the covered package is the same as the tested package, it returns the empty string.
 // Otherwise it is a comma-separated human-readable list of packages beginning with
@@ -1421,7 +1462,7 @@
 func (t *testFuncs) load(filename, pkg string, doImport, seen *bool) error {
 	f, err := parser.ParseFile(testFileSet, filename, nil, parser.ParseComments)
 	if err != nil {
-		return expandScanner(err)
+		return base.ExpandScanner(err)
 	}
 	for _, d := range f.Decls {
 		n, ok := d.(*ast.FuncDecl)
@@ -1482,7 +1523,7 @@
 package main
 
 import (
-{{if .NeedOS}}
+{{if not .TestMain}}
 	"os"
 {{end}}
 	"testing"
@@ -1498,10 +1539,8 @@
 	_cover{{$i}} {{$p.Package.ImportPath | printf "%q"}}
 {{end}}
 
-{{if .IsIOS}}
-	"os/signal"
+{{if .NeedCgo}}
 	_ "runtime/cgo"
-	"syscall"
 {{end}}
 )
 
@@ -1523,6 +1562,10 @@
 {{end}}
 }
 
+func init() {
+	testdeps.ImportPath = {{.ImportPath | printf "%q"}}
+}
+
 {{if .CoverEnabled}}
 
 // Only updated by init functions, so no need for atomicity.
@@ -1563,32 +1606,6 @@
 {{end}}
 
 func main() {
-{{if .IsIOS}}
-	// Send a SIGUSR2, which will be intercepted by LLDB to
-	// tell the test harness that installation was successful.
-	// See misc/ios/go_darwin_arm_exec.go.
-	signal.Notify(make(chan os.Signal), syscall.SIGUSR2)
-	syscall.Kill(0, syscall.SIGUSR2)
-	signal.Reset(syscall.SIGUSR2)
-
-	// The first argument supplied to an iOS test is an offset
-	// suffix for the current working directory.
-	// Process it here, and remove it from os.Args.
-	const hdr = "cwdSuffix="
-	if len(os.Args) < 2 || len(os.Args[1]) <= len(hdr) || os.Args[1][:len(hdr)] != hdr {
-		panic("iOS test not passed a working directory suffix")
-	}
-	suffix := os.Args[1][len(hdr):]
-	dir, err := os.Getwd()
-	if err != nil {
-		panic(err)
-	}
-	if err := os.Chdir(dir + "/" + suffix); err != nil {
-		panic(err)
-	}
-	os.Args = append([]string{os.Args[0]}, os.Args[2:]...)
-{{end}}
-
 {{if .CoverEnabled}}
 	testing.RegisterCover(testing.Cover{
 		Mode: {{printf "%q" .CoverMode}},
diff --git a/libgo/go/cmd/go/internal/test/testflag.go b/libgo/go/cmd/go/internal/test/testflag.go
new file mode 100644
index 0000000..bff8656
--- /dev/null
+++ b/libgo/go/cmd/go/internal/test/testflag.go
@@ -0,0 +1,211 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package test
+
+import (
+	"flag"
+	"os"
+	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/cmdflag"
+	"cmd/go/internal/str"
+	"cmd/go/internal/work"
+)
+
+const cmd = "test"
+
+// The flag handling part of go test is large and distracting.
+// We can't use the flag package because some of the flags from
+// our command line are for us, and some are for 6.out, and
+// some are for both.
+
+// testFlagDefn is the set of flags we process.
+var testFlagDefn = []*cmdflag.Defn{
+	// local.
+	{Name: "c", BoolVar: &testC},
+	{Name: "i", BoolVar: &cfg.BuildI},
+	{Name: "o"},
+	{Name: "cover", BoolVar: &testCover},
+	{Name: "covermode"},
+	{Name: "coverpkg"},
+	{Name: "exec"},
+
+	// Passed to 6.out, adding a "test." prefix to the name if necessary: -v becomes -test.v.
+	{Name: "bench", PassToTest: true},
+	{Name: "benchmem", BoolVar: new(bool), PassToTest: true},
+	{Name: "benchtime", PassToTest: true},
+	{Name: "count", PassToTest: true},
+	{Name: "coverprofile", PassToTest: true},
+	{Name: "cpu", PassToTest: true},
+	{Name: "cpuprofile", PassToTest: true},
+	{Name: "list", PassToTest: true},
+	{Name: "memprofile", PassToTest: true},
+	{Name: "memprofilerate", PassToTest: true},
+	{Name: "blockprofile", PassToTest: true},
+	{Name: "blockprofilerate", PassToTest: true},
+	{Name: "mutexprofile", PassToTest: true},
+	{Name: "mutexprofilefraction", PassToTest: true},
+	{Name: "outputdir", PassToTest: true},
+	{Name: "parallel", PassToTest: true},
+	{Name: "run", PassToTest: true},
+	{Name: "short", BoolVar: new(bool), PassToTest: true},
+	{Name: "timeout", PassToTest: true},
+	{Name: "trace", PassToTest: true},
+	{Name: "v", BoolVar: &testV, PassToTest: true},
+}
+
+// add build flags to testFlagDefn
+func init() {
+	var cmd base.Command
+	work.AddBuildFlags(&cmd)
+	cmd.Flag.VisitAll(func(f *flag.Flag) {
+		if f.Name == "v" {
+			// test overrides the build -v flag
+			return
+		}
+		testFlagDefn = append(testFlagDefn, &cmdflag.Defn{
+			Name:  f.Name,
+			Value: f.Value,
+		})
+	})
+}
+
+// testFlags processes the command line, grabbing -x and -c, rewriting known flags
+// to have "test" before them, and reading the command line for the 6.out.
+// Unfortunately for us, we need to do our own flag processing because go test
+// grabs some flags but otherwise its command line is just a holding place for
+// pkg.test's arguments.
+// We allow known flags both before and after the package name list,
+// to allow both
+//	go test fmt -custom-flag-for-fmt-test
+//	go test -x math
+func testFlags(args []string) (packageNames, passToTest []string) {
+	inPkg := false
+	outputDir := ""
+	var explicitArgs []string
+	for i := 0; i < len(args); i++ {
+		if !strings.HasPrefix(args[i], "-") {
+			if !inPkg && packageNames == nil {
+				// First package name we've seen.
+				inPkg = true
+			}
+			if inPkg {
+				packageNames = append(packageNames, args[i])
+				continue
+			}
+		}
+
+		if inPkg {
+			// Found an argument beginning with "-"; end of package list.
+			inPkg = false
+		}
+
+		f, value, extraWord := cmdflag.Parse(cmd, testFlagDefn, args, i)
+		if f == nil {
+			// This is a flag we do not know; we must assume
+			// that any args we see after this might be flag
+			// arguments, not package names.
+			inPkg = false
+			if packageNames == nil {
+				// make non-nil: we have seen the empty package list
+				packageNames = []string{}
+			}
+			if args[i] == "-args" || args[i] == "--args" {
+				// -args or --args signals that everything that follows
+				// should be passed to the test.
+				explicitArgs = args[i+1:]
+				break
+			}
+			passToTest = append(passToTest, args[i])
+			continue
+		}
+		if f.Value != nil {
+			if err := f.Value.Set(value); err != nil {
+				base.Fatalf("invalid flag argument for -%s: %v", f.Name, err)
+			}
+		} else {
+			// Test-only flags.
+			// Arguably should be handled by f.Value, but aren't.
+			switch f.Name {
+			// bool flags.
+			case "c", "i", "v", "cover":
+				cmdflag.SetBool(cmd, f.BoolVar, value)
+			case "o":
+				testO = value
+				testNeedBinary = true
+			case "exec":
+				xcmd, err := str.SplitQuotedFields(value)
+				if err != nil {
+					base.Fatalf("invalid flag argument for -%s: %v", f.Name, err)
+				}
+				work.ExecCmd = xcmd
+			case "bench":
+				// record that we saw the flag; don't care about the value
+				testBench = true
+			case "list":
+				testList = true
+			case "timeout":
+				testTimeout = value
+			case "blockprofile", "cpuprofile", "memprofile", "mutexprofile":
+				testProfile = true
+				testNeedBinary = true
+			case "trace":
+				testProfile = true
+			case "coverpkg":
+				testCover = true
+				if value == "" {
+					testCoverPaths = nil
+				} else {
+					testCoverPaths = strings.Split(value, ",")
+				}
+			case "coverprofile":
+				testCover = true
+				testProfile = true
+			case "covermode":
+				switch value {
+				case "set", "count", "atomic":
+					testCoverMode = value
+				default:
+					base.Fatalf("invalid flag argument for -covermode: %q", value)
+				}
+				testCover = true
+			case "outputdir":
+				outputDir = value
+			}
+		}
+		if extraWord {
+			i++
+		}
+		if f.PassToTest {
+			passToTest = append(passToTest, "-test."+f.Name+"="+value)
+		}
+	}
+
+	if testCoverMode == "" {
+		testCoverMode = "set"
+		if cfg.BuildRace {
+			// Default coverage mode is atomic when -race is set.
+			testCoverMode = "atomic"
+		}
+	}
+
+	if cfg.BuildRace && testCoverMode != "atomic" {
+		base.Fatalf(`-covermode must be "atomic", not %q, when -race is enabled`, testCoverMode)
+	}
+
+	// Tell the test what directory we're running in, so it can write the profiles there.
+	if testProfile && outputDir == "" {
+		dir, err := os.Getwd()
+		if err != nil {
+			base.Fatalf("error from os.Getwd: %s", err)
+		}
+		passToTest = append(passToTest, "-test.outputdir", dir)
+	}
+
+	passToTest = append(passToTest, explicitArgs...)
+	return
+}
diff --git a/libgo/go/cmd/go/internal/tool/tool.go b/libgo/go/cmd/go/internal/tool/tool.go
new file mode 100644
index 0000000..7dd5510
--- /dev/null
+++ b/libgo/go/cmd/go/internal/tool/tool.go
@@ -0,0 +1,135 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package tool implements the ``go tool'' command.
+package tool
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"sort"
+	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+)
+
+var CmdTool = &base.Command{
+	Run:       runTool,
+	UsageLine: "tool [-n] command [args...]",
+	Short:     "run specified go tool",
+	Long: `
+Tool runs the go tool command identified by the arguments.
+With no arguments it prints the list of known tools.
+
+The -n flag causes tool to print the command that would be
+executed but not execute it.
+
+For more about each tool command, see 'go tool command -h'.
+`,
+}
+
+var toolN bool
+
+// Return whether tool can be expected in the gccgo tool directory.
+// Other binaries could be in the same directory so don't
+// show those with the 'go tool' command.
+func isGccgoTool(tool string) bool {
+	switch tool {
+	case "cgo", "fix", "cover", "godoc", "vet":
+		return true
+	}
+	return false
+}
+
+func init() {
+	CmdTool.Flag.BoolVar(&toolN, "n", false, "")
+}
+
+func runTool(cmd *base.Command, args []string) {
+	if len(args) == 0 {
+		listTools()
+		return
+	}
+	toolName := args[0]
+	// The tool name must be lower-case letters, numbers or underscores.
+	for _, c := range toolName {
+		switch {
+		case 'a' <= c && c <= 'z', '0' <= c && c <= '9', c == '_':
+		default:
+			fmt.Fprintf(os.Stderr, "go tool: bad tool name %q\n", toolName)
+			base.SetExitStatus(2)
+			return
+		}
+	}
+	toolPath := base.Tool(toolName)
+	if toolPath == "" {
+		return
+	}
+	if toolN {
+		cmd := toolPath
+		if len(args) > 1 {
+			cmd += " " + strings.Join(args[1:], " ")
+		}
+		fmt.Printf("%s\n", cmd)
+		return
+	}
+	args[0] = toolPath // in case the tool wants to re-exec itself, e.g. cmd/dist
+	toolCmd := &exec.Cmd{
+		Path:   toolPath,
+		Args:   args,
+		Stdin:  os.Stdin,
+		Stdout: os.Stdout,
+		Stderr: os.Stderr,
+		// Set $GOROOT, mainly for go tool dist.
+		Env: base.MergeEnvLists([]string{"GOROOT=" + cfg.GOROOT}, os.Environ()),
+	}
+	err := toolCmd.Run()
+	if err != nil {
+		// Only print about the exit status if the command
+		// didn't even run (not an ExitError) or it didn't exit cleanly
+		// or we're printing command lines too (-x mode).
+		// Assume if command exited cleanly (even with non-zero status)
+		// it printed any messages it wanted to print.
+		if e, ok := err.(*exec.ExitError); !ok || !e.Exited() || cfg.BuildX {
+			fmt.Fprintf(os.Stderr, "go tool %s: %s\n", toolName, err)
+		}
+		base.SetExitStatus(1)
+		return
+	}
+}
+
+// listTools prints a list of the available tools in the tools directory.
+func listTools() {
+	f, err := os.Open(base.ToolDir)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "go tool: no tool directory: %s\n", err)
+		base.SetExitStatus(2)
+		return
+	}
+	defer f.Close()
+	names, err := f.Readdirnames(-1)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "go tool: can't read directory: %s\n", err)
+		base.SetExitStatus(2)
+		return
+	}
+
+	sort.Strings(names)
+	for _, name := range names {
+		// Unify presentation by going to lower case.
+		name = strings.ToLower(name)
+		// If it's windows, don't show the .exe suffix.
+		if base.ToolIsWindows && strings.HasSuffix(name, base.ToolWindowsExtension) {
+			name = name[:len(name)-len(base.ToolWindowsExtension)]
+		}
+		// The tool directory used by gccgo will have other binaries
+		// in addition to go tools. Only display go tools here.
+		if cfg.BuildToolchainName == "gccgo" && !isGccgoTool(name) {
+			continue
+		}
+		fmt.Println(name)
+	}
+}
diff --git a/libgo/go/cmd/go/version.go b/libgo/go/cmd/go/internal/version/version.go
similarity index 72%
rename from libgo/go/cmd/go/version.go
rename to libgo/go/cmd/go/internal/version/version.go
index 3045f35..c3f7d73 100644
--- a/libgo/go/cmd/go/version.go
+++ b/libgo/go/cmd/go/internal/version/version.go
@@ -2,21 +2,24 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+// Package version implements the ``go version'' command.
+package version
 
 import (
 	"fmt"
 	"runtime"
+
+	"cmd/go/internal/base"
 )
 
-var cmdVersion = &Command{
+var CmdVersion = &base.Command{
 	Run:       runVersion,
 	UsageLine: "version",
 	Short:     "print Go version",
 	Long:      `Version prints the Go version, as reported by runtime.Version.`,
 }
 
-func runVersion(cmd *Command, args []string) {
+func runVersion(cmd *base.Command, args []string) {
 	if len(args) != 0 {
 		cmd.Usage()
 	}
diff --git a/libgo/go/cmd/go/internal/vet/vet.go b/libgo/go/cmd/go/internal/vet/vet.go
new file mode 100644
index 0000000..ddacd08
--- /dev/null
+++ b/libgo/go/cmd/go/internal/vet/vet.go
@@ -0,0 +1,56 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package vet implements the ``go vet'' command.
+package vet
+
+import (
+	"path/filepath"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/str"
+)
+
+var CmdVet = &base.Command{
+	Run:         runVet,
+	CustomFlags: true,
+	UsageLine:   "vet [-n] [-x] [build flags] [vet flags] [packages]",
+	Short:       "run go tool vet on packages",
+	Long: `
+Vet runs the Go vet command on the packages named by the import paths.
+
+For more about vet and its flags, see 'go doc cmd/vet'.
+For more about specifying packages, see 'go help packages'.
+
+The -n flag prints commands that would be executed.
+The -x flag prints commands as they are executed.
+
+For more about build flags, see 'go help build'.
+
+See also: go fmt, go fix.
+	`,
+}
+
+func runVet(cmd *base.Command, args []string) {
+	vetFlags, packages := vetFlags(args)
+	for _, p := range load.Packages(packages) {
+		// Vet expects to be given a set of files all from the same package.
+		// Run once for package p and once for package p_test.
+		if len(p.GoFiles)+len(p.CgoFiles)+len(p.TestGoFiles) > 0 {
+			runVetFiles(p, vetFlags, str.StringList(p.GoFiles, p.CgoFiles, p.TestGoFiles, p.SFiles))
+		}
+		if len(p.XTestGoFiles) > 0 {
+			runVetFiles(p, vetFlags, str.StringList(p.XTestGoFiles))
+		}
+	}
+}
+
+func runVetFiles(p *load.Package, flags, files []string) {
+	for i := range files {
+		files[i] = filepath.Join(p.Dir, files[i])
+	}
+	base.Run(cfg.BuildToolexec, base.Tool("vet"), flags, base.RelPaths(files))
+}
diff --git a/libgo/go/cmd/go/internal/vet/vetflag.go b/libgo/go/cmd/go/internal/vet/vetflag.go
new file mode 100644
index 0000000..8cd21bb
--- /dev/null
+++ b/libgo/go/cmd/go/internal/vet/vetflag.go
@@ -0,0 +1,99 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package vet
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cmdflag"
+	"cmd/go/internal/work"
+)
+
+const cmd = "vet"
+
+// vetFlagDefn is the set of flags we process.
+var vetFlagDefn = []*cmdflag.Defn{
+	// Note: Some flags, in particular -tags and -v, are known to
+	// vet but also defined as build flags. This works fine, so we
+	// don't define them here but use AddBuildFlags to init them.
+	// However some, like -x, are known to the build but not
+	// to vet. We handle them in vetFlags.
+
+	// local.
+	{Name: "all", BoolVar: new(bool)},
+	{Name: "asmdecl", BoolVar: new(bool)},
+	{Name: "assign", BoolVar: new(bool)},
+	{Name: "atomic", BoolVar: new(bool)},
+	{Name: "bool", BoolVar: new(bool)},
+	{Name: "buildtags", BoolVar: new(bool)},
+	{Name: "cgocall", BoolVar: new(bool)},
+	{Name: "composites", BoolVar: new(bool)},
+	{Name: "copylocks", BoolVar: new(bool)},
+	{Name: "httpresponse", BoolVar: new(bool)},
+	{Name: "lostcancel", BoolVar: new(bool)},
+	{Name: "methods", BoolVar: new(bool)},
+	{Name: "nilfunc", BoolVar: new(bool)},
+	{Name: "printf", BoolVar: new(bool)},
+	{Name: "printfuncs"},
+	{Name: "rangeloops", BoolVar: new(bool)},
+	{Name: "shadow", BoolVar: new(bool)},
+	{Name: "shadowstrict", BoolVar: new(bool)},
+	{Name: "source", BoolVar: new(bool)},
+	{Name: "structtags", BoolVar: new(bool)},
+	{Name: "tests", BoolVar: new(bool)},
+	{Name: "unreachable", BoolVar: new(bool)},
+	{Name: "unsafeptr", BoolVar: new(bool)},
+	{Name: "unusedfuncs"},
+	{Name: "unusedresult", BoolVar: new(bool)},
+	{Name: "unusedstringmethods"},
+}
+
+// add build flags to vetFlagDefn.
+func init() {
+	var cmd base.Command
+	work.AddBuildFlags(&cmd)
+	cmd.Flag.VisitAll(func(f *flag.Flag) {
+		vetFlagDefn = append(vetFlagDefn, &cmdflag.Defn{
+			Name:  f.Name,
+			Value: f.Value,
+		})
+	})
+}
+
+// vetFlags processes the command line, splitting it at the first non-flag
+// into the list of flags and list of packages.
+func vetFlags(args []string) (passToVet, packageNames []string) {
+	for i := 0; i < len(args); i++ {
+		if !strings.HasPrefix(args[i], "-") {
+			return args[:i], args[i:]
+		}
+
+		f, value, extraWord := cmdflag.Parse(cmd, vetFlagDefn, args, i)
+		if f == nil {
+			fmt.Fprintf(os.Stderr, "vet: flag %q not defined\n", args[i])
+			fmt.Fprintf(os.Stderr, "Run \"go help vet\" for more information\n")
+			os.Exit(2)
+		}
+		if f.Value != nil {
+			if err := f.Value.Set(value); err != nil {
+				base.Fatalf("invalid flag argument for -%s: %v", f.Name, err)
+			}
+			switch f.Name {
+			// Flags known to the build but not to vet, so must be dropped.
+			case "x", "n":
+				args = append(args[:i], args[i+1:]...)
+				i--
+			}
+		}
+		if extraWord {
+			i++
+		}
+	}
+	return args, nil
+}
diff --git a/libgo/go/cmd/go/internal/web/bootstrap.go b/libgo/go/cmd/go/internal/web/bootstrap.go
new file mode 100644
index 0000000..d1d4621
--- /dev/null
+++ b/libgo/go/cmd/go/internal/web/bootstrap.go
@@ -0,0 +1,37 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build cmd_go_bootstrap
+
+// This code is compiled only into the bootstrap 'go' binary.
+// These stubs avoid importing packages with large dependency
+// trees, like the use of "net/http" in vcs.go.
+
+package web
+
+import (
+	"errors"
+	"io"
+)
+
+var errHTTP = errors.New("no http in bootstrap go command")
+
+type HTTPError struct {
+	StatusCode int
+}
+
+func (e *HTTPError) Error() string {
+	panic("unreachable")
+}
+
+func Get(url string) ([]byte, error) {
+	return nil, errHTTP
+}
+
+func GetMaybeInsecure(importPath string, security SecurityMode) (string, io.ReadCloser, error) {
+	return "", nil, errHTTP
+}
+
+func QueryEscape(s string) string { panic("unreachable") }
+func OpenBrowser(url string) bool { panic("unreachable") }
diff --git a/libgo/go/cmd/go/http.go b/libgo/go/cmd/go/internal/web/http.go
similarity index 73%
rename from libgo/go/cmd/go/http.go
rename to libgo/go/cmd/go/internal/web/http.go
index dcb4e9f..6e347fb 100644
--- a/libgo/go/cmd/go/http.go
+++ b/libgo/go/cmd/go/internal/web/http.go
@@ -9,10 +9,9 @@
 // to avoid needing to build net (and thus use cgo) during the
 // bootstrap process.
 
-package main
+package web
 
 import (
-	"cmd/internal/browser"
 	"crypto/tls"
 	"fmt"
 	"io"
@@ -21,6 +20,9 @@
 	"net/http"
 	"net/url"
 	"time"
+
+	"cmd/go/internal/cfg"
+	"cmd/internal/browser"
 )
 
 // httpClient is the default HTTP client, but a variable so it can be
@@ -40,25 +42,25 @@
 	},
 }
 
-type httpError struct {
+type HTTPError struct {
 	status     string
-	statusCode int
+	StatusCode int
 	url        string
 }
 
-func (e *httpError) Error() string {
+func (e *HTTPError) Error() string {
 	return fmt.Sprintf("%s: %s", e.url, e.status)
 }
 
-// httpGET returns the data from an HTTP GET request for the given URL.
-func httpGET(url string) ([]byte, error) {
+// Get returns the data from an HTTP GET request for the given URL.
+func Get(url string) ([]byte, error) {
 	resp, err := httpClient.Get(url)
 	if err != nil {
 		return nil, err
 	}
 	defer resp.Body.Close()
 	if resp.StatusCode != 200 {
-		err := &httpError{status: resp.Status, statusCode: resp.StatusCode, url: url}
+		err := &HTTPError{status: resp.Status, StatusCode: resp.StatusCode, url: url}
 
 		return nil, err
 	}
@@ -69,9 +71,9 @@
 	return b, nil
 }
 
-// httpsOrHTTP returns the body of either the importPath's
-// https resource or, if unavailable, the http resource.
-func httpsOrHTTP(importPath string, security securityMode) (urlStr string, body io.ReadCloser, err error) {
+// GetMaybeInsecure returns the body of either the importPath's
+// https resource or, if unavailable and permitted by the security mode, the http resource.
+func GetMaybeInsecure(importPath string, security SecurityMode) (urlStr string, body io.ReadCloser, err error) {
 	fetch := func(scheme string) (urlStr string, res *http.Response, err error) {
 		u, err := url.Parse(scheme + "://" + importPath)
 		if err != nil {
@@ -79,10 +81,10 @@
 		}
 		u.RawQuery = "go-get=1"
 		urlStr = u.String()
-		if buildV {
+		if cfg.BuildV {
 			log.Printf("Fetching %s", urlStr)
 		}
-		if security == insecure && scheme == "https" { // fail earlier
+		if security == Insecure && scheme == "https" { // fail earlier
 			res, err = impatientInsecureHTTPClient.Get(urlStr)
 		} else {
 			res, err = httpClient.Get(urlStr)
@@ -96,10 +98,10 @@
 	}
 	urlStr, res, err := fetch("https")
 	if err != nil {
-		if buildV {
+		if cfg.BuildV {
 			log.Printf("https fetch failed: %v", err)
 		}
-		if security == insecure {
+		if security == Insecure {
 			closeBody(res)
 			urlStr, res, err = fetch("http")
 		}
@@ -110,11 +112,11 @@
 	}
 	// Note: accepting a non-200 OK here, so people can serve a
 	// meta import in their http 404 page.
-	if buildV {
+	if cfg.BuildV {
 		log.Printf("Parsing meta tags from %s (status code %d)", urlStr, res.StatusCode)
 	}
 	return urlStr, res.Body, nil
 }
 
-func queryEscape(s string) string { return url.QueryEscape(s) }
-func openBrowser(url string) bool { return browser.Open(url) }
+func QueryEscape(s string) string { return url.QueryEscape(s) }
+func OpenBrowser(url string) bool { return browser.Open(url) }
diff --git a/libgo/go/cmd/go/internal/web/security.go b/libgo/go/cmd/go/internal/web/security.go
new file mode 100644
index 0000000..1dc6f1b
--- /dev/null
+++ b/libgo/go/cmd/go/internal/web/security.go
@@ -0,0 +1,16 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package web defines helper routines for accessing HTTP/HTTPS resources.
+package web
+
+// SecurityMode specifies whether a function should make network
+// calls using insecure transports (eg, plain text HTTP).
+// The zero value is "secure".
+type SecurityMode int
+
+const (
+	Secure SecurityMode = iota
+	Insecure
+)
diff --git a/libgo/go/cmd/go/build.go b/libgo/go/cmd/go/internal/work/build.go
similarity index 64%
rename from libgo/go/cmd/go/build.go
rename to libgo/go/cmd/go/internal/work/build.go
index a62bc86..de8c493 100644
--- a/libgo/go/cmd/go/build.go
+++ b/libgo/go/cmd/go/internal/work/build.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package main
+package work
 
 import (
 	"bufio"
@@ -26,9 +26,15 @@
 	"strings"
 	"sync"
 	"time"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/buildid"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/str"
 )
 
-var cmdBuild = &Command{
+var CmdBuild = &base.Command{
 	UsageLine: "build [-o output] [-i] [build flags] [packages]",
 	Short:     "compile packages and dependencies",
 	Long: `
@@ -97,8 +103,8 @@
 		a suffix to use in the name of the package installation directory,
 		in order to keep output separate from default builds.
 		If using the -race flag, the install suffix is automatically set to race
-		or, if set explicitly, has _race appended to it.  Likewise for the -msan
-		flag.  Using a -buildmode option that requires non-default compile flags
+		or, if set explicitly, has _race appended to it. Likewise for the -msan
+		flag. Using a -buildmode option that requires non-default compile flags
 		has a similar effect.
 	-ldflags 'flag list'
 		arguments to pass on each go tool link invocation.
@@ -110,16 +116,17 @@
 		For example, when building with a non-standard configuration,
 		use -pkgdir to keep generated packages in a separate location.
 	-tags 'tag list'
-		a list of build tags to consider satisfied during the build.
-		For more information about build tags, see the description of
+		a space-separated list of build tags to consider satisfied during the
+		build. For more information about build tags, see the description of
 		build constraints in the documentation for the go/build package.
 	-toolexec 'cmd args'
 		a program to use to invoke toolchain programs like vet and asm.
 		For example, instead of running asm, the go command will run
 		'cmd args /path/to/asm <arguments for asm>'.
 
-The list flags accept a space-separated list of strings. To embed spaces
-in an element in the list, surround it with either single or double quotes.
+All the flags that take a list of arguments accept a space-separated
+list of strings. To embed spaces in an element in the list, surround
+it with either single or double quotes.
 
 For more about specifying packages, see 'go help packages'.
 For more about where packages and binaries are installed,
@@ -137,112 +144,85 @@
 	`,
 }
 
+const concurrentGCBackendCompilationEnabledByDefault = true
+
 func init() {
 	// break init cycle
-	cmdBuild.Run = runBuild
-	cmdInstall.Run = runInstall
+	CmdBuild.Run = runBuild
+	CmdInstall.Run = runInstall
 
-	cmdBuild.Flag.BoolVar(&buildI, "i", false, "")
+	CmdBuild.Flag.BoolVar(&cfg.BuildI, "i", false, "")
+	CmdBuild.Flag.StringVar(&cfg.BuildO, "o", "", "output file")
 
-	addBuildFlags(cmdBuild)
-	addBuildFlags(cmdInstall)
+	AddBuildFlags(CmdBuild)
+	AddBuildFlags(CmdInstall)
 }
 
-// Flags set by multiple commands.
-var buildA bool               // -a flag
-var buildN bool               // -n flag
-var buildP = runtime.NumCPU() // -p flag
-var buildV bool               // -v flag
-var buildX bool               // -x flag
-var buildI bool               // -i flag
-var buildO = cmdBuild.Flag.String("o", "", "output file")
-var buildWork bool           // -work flag
+// Note that flags consulted by other parts of the code
+// (for example, buildV) are in cmd/go/internal/cfg.
+
 var buildAsmflags []string   // -asmflags flag
 var buildGcflags []string    // -gcflags flag
-var buildLdflags []string    // -ldflags flag
 var buildGccgoflags []string // -gccgoflags flag
-var buildRace bool           // -race flag
-var buildMSan bool           // -msan flag
-var buildToolExec []string   // -toolexec flag
-var buildBuildmode string    // -buildmode flag
-var buildLinkshared bool     // -linkshared flag
-var buildPkgdir string       // -pkgdir flag
 
-// Require the source for go std packages
-var reqStdPkgSrc bool
-var buildContext = build.Default
-var buildToolchain toolchain = noToolchain{}
+var BuildToolchain toolchain = noToolchain{}
 var ldBuildmode string
 
 // buildCompiler implements flag.Var.
 // It implements Set by updating both
-// buildToolchain and buildContext.Compiler.
+// BuildToolchain and buildContext.Compiler.
 type buildCompiler struct{}
 
 func (c buildCompiler) Set(value string) error {
 	switch value {
 	case "gc":
-		buildToolchain = gcToolchain{}
+		BuildToolchain = gcToolchain{}
 	case "gccgo":
-		buildToolchain = gccgoToolchain{}
+		BuildToolchain = gccgoToolchain{}
 	default:
 		return fmt.Errorf("unknown compiler %q", value)
 	}
-	buildContext.Compiler = value
+	cfg.BuildToolchainName = value
+	cfg.BuildToolchainCompiler = BuildToolchain.compiler
+	cfg.BuildToolchainLinker = BuildToolchain.linker
+	cfg.BuildContext.Compiler = value
 	return nil
 }
 
 func (c buildCompiler) String() string {
-	return buildContext.Compiler
+	return cfg.BuildContext.Compiler
 }
 
 func init() {
 	switch build.Default.Compiler {
-	case "gc":
-		buildToolchain = gcToolchain{}
-	case "gccgo":
-		buildToolchain = gccgoToolchain{}
+	case "gc", "gccgo":
+		buildCompiler{}.Set(build.Default.Compiler)
 	}
 }
 
 // addBuildFlags adds the flags common to the build, clean, get,
 // install, list, run, and test commands.
-func addBuildFlags(cmd *Command) {
-	cmd.Flag.BoolVar(&buildA, "a", false, "")
-	cmd.Flag.BoolVar(&buildN, "n", false, "")
-	cmd.Flag.IntVar(&buildP, "p", buildP, "")
-	cmd.Flag.BoolVar(&buildV, "v", false, "")
-	cmd.Flag.BoolVar(&buildX, "x", false, "")
+func AddBuildFlags(cmd *base.Command) {
+	cmd.Flag.BoolVar(&cfg.BuildA, "a", false, "")
+	cmd.Flag.BoolVar(&cfg.BuildN, "n", false, "")
+	cmd.Flag.IntVar(&cfg.BuildP, "p", cfg.BuildP, "")
+	cmd.Flag.BoolVar(&cfg.BuildV, "v", false, "")
+	cmd.Flag.BoolVar(&cfg.BuildX, "x", false, "")
 
-	cmd.Flag.Var((*stringsFlag)(&buildAsmflags), "asmflags", "")
+	cmd.Flag.Var((*base.StringsFlag)(&buildAsmflags), "asmflags", "")
 	cmd.Flag.Var(buildCompiler{}, "compiler", "")
-	cmd.Flag.StringVar(&buildBuildmode, "buildmode", "default", "")
-	cmd.Flag.Var((*stringsFlag)(&buildGcflags), "gcflags", "")
-	cmd.Flag.Var((*stringsFlag)(&buildGccgoflags), "gccgoflags", "")
-	cmd.Flag.StringVar(&buildContext.InstallSuffix, "installsuffix", "", "")
-	cmd.Flag.Var((*stringsFlag)(&buildLdflags), "ldflags", "")
-	cmd.Flag.BoolVar(&buildLinkshared, "linkshared", false, "")
-	cmd.Flag.StringVar(&buildPkgdir, "pkgdir", "", "")
-	cmd.Flag.BoolVar(&buildRace, "race", false, "")
-	cmd.Flag.BoolVar(&buildMSan, "msan", false, "")
-	cmd.Flag.Var((*stringsFlag)(&buildContext.BuildTags), "tags", "")
-	cmd.Flag.Var((*stringsFlag)(&buildToolExec), "toolexec", "")
-	cmd.Flag.BoolVar(&buildWork, "work", false, "")
-	switch build.Default.Compiler {
-	case "gc":
-		reqStdPkgSrc = true
-	case "gccgo":
-		reqStdPkgSrc = false
-	}
-}
-
-func addBuildFlagsNX(cmd *Command) {
-	cmd.Flag.BoolVar(&buildN, "n", false, "")
-	cmd.Flag.BoolVar(&buildX, "x", false, "")
-}
-
-func isSpaceByte(c byte) bool {
-	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
+	cmd.Flag.StringVar(&cfg.BuildBuildmode, "buildmode", "default", "")
+	cmd.Flag.Var((*base.StringsFlag)(&buildGcflags), "gcflags", "")
+	cmd.Flag.Var((*base.StringsFlag)(&buildGccgoflags), "gccgoflags", "")
+	cmd.Flag.StringVar(&cfg.BuildContext.InstallSuffix, "installsuffix", "", "")
+	cmd.Flag.Var((*base.StringsFlag)(&cfg.BuildLdflags), "ldflags", "")
+	cmd.Flag.BoolVar(&cfg.BuildLinkshared, "linkshared", false, "")
+	cmd.Flag.StringVar(&cfg.BuildPkgdir, "pkgdir", "", "")
+	cmd.Flag.BoolVar(&cfg.BuildRace, "race", false, "")
+	cmd.Flag.BoolVar(&cfg.BuildMSan, "msan", false, "")
+	cmd.Flag.Var((*base.StringsFlag)(&cfg.BuildContext.BuildTags), "tags", "")
+	cmd.Flag.Var((*base.StringsFlag)(&cfg.BuildToolexec), "toolexec", "")
+	cmd.Flag.BoolVar(&cfg.BuildWork, "work", false, "")
 }
 
 // fileExtSplit expects a filename and returns the name
@@ -257,58 +237,7 @@
 	return
 }
 
-type stringsFlag []string
-
-func (v *stringsFlag) Set(s string) error {
-	var err error
-	*v, err = splitQuotedFields(s)
-	if *v == nil {
-		*v = []string{}
-	}
-	return err
-}
-
-func splitQuotedFields(s string) ([]string, error) {
-	// Split fields allowing '' or "" around elements.
-	// Quotes further inside the string do not count.
-	var f []string
-	for len(s) > 0 {
-		for len(s) > 0 && isSpaceByte(s[0]) {
-			s = s[1:]
-		}
-		if len(s) == 0 {
-			break
-		}
-		// Accepted quoted string. No unescaping inside.
-		if s[0] == '"' || s[0] == '\'' {
-			quote := s[0]
-			s = s[1:]
-			i := 0
-			for i < len(s) && s[i] != quote {
-				i++
-			}
-			if i >= len(s) {
-				return nil, fmt.Errorf("unterminated %c string", quote)
-			}
-			f = append(f, s[:i])
-			s = s[i+1:]
-			continue
-		}
-		i := 0
-		for i < len(s) && !isSpaceByte(s[i]) {
-			i++
-		}
-		f = append(f, s[:i])
-		s = s[i:]
-	}
-	return f, nil
-}
-
-func (v *stringsFlag) String() string {
-	return "<stringsFlag>"
-}
-
-func pkgsMain(pkgs []*Package) (res []*Package) {
+func pkgsMain(pkgs []*load.Package) (res []*load.Package) {
 	for _, p := range pkgs {
 		if p.Name == "main" {
 			res = append(res, p)
@@ -317,7 +246,7 @@
 	return res
 }
 
-func pkgsNotMain(pkgs []*Package) (res []*Package) {
+func pkgsNotMain(pkgs []*load.Package) (res []*load.Package) {
 	for _, p := range pkgs {
 		if p.Name != "main" {
 			res = append(res, p)
@@ -326,22 +255,24 @@
 	return res
 }
 
-var pkgsFilter = func(pkgs []*Package) []*Package { return pkgs }
+func oneMainPkg(pkgs []*load.Package) []*load.Package {
+	if len(pkgs) != 1 || pkgs[0].Name != "main" {
+		base.Fatalf("-buildmode=%s requires exactly one main package", cfg.BuildBuildmode)
+	}
+	return pkgs
+}
 
-func buildModeInit() {
-	_, gccgo := buildToolchain.(gccgoToolchain)
+var pkgsFilter = func(pkgs []*load.Package) []*load.Package { return pkgs }
+
+func BuildModeInit() {
+	gccgo := cfg.BuildToolchainName == "gccgo"
 	var codegenArg string
-	platform := goos + "/" + goarch
-	switch buildBuildmode {
+	platform := cfg.Goos + "/" + cfg.Goarch
+	switch cfg.BuildBuildmode {
 	case "archive":
 		pkgsFilter = pkgsNotMain
 	case "c-archive":
-		pkgsFilter = func(p []*Package) []*Package {
-			if len(p) != 1 || p[0].Name != "main" {
-				fatalf("-buildmode=c-archive requires exactly one main package")
-			}
-			return p
-		}
+		pkgsFilter = oneMainPkg
 		if gccgo {
 			codegenArg = "-fPIC"
 		} else {
@@ -349,7 +280,7 @@
 			case "darwin/arm", "darwin/arm64":
 				codegenArg = "-shared"
 			default:
-				switch goos {
+				switch cfg.Goos {
 				case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
 					// Use -shared so that the result is
 					// suitable for inclusion in a PIE or
@@ -358,10 +289,10 @@
 				}
 			}
 		}
-		exeSuffix = ".a"
+		cfg.ExeSuffix = ".a"
 		ldBuildmode = "c-archive"
 	case "c-shared":
-		pkgsFilter = pkgsMain
+		pkgsFilter = oneMainPkg
 		if gccgo {
 			codegenArg = "-fPIC"
 		} else {
@@ -371,7 +302,7 @@
 				codegenArg = "-shared"
 			case "darwin/amd64", "darwin/386":
 			default:
-				fatalf("-buildmode=c-shared not supported on %s\n", platform)
+				base.Fatalf("-buildmode=c-shared not supported on %s\n", platform)
 			}
 		}
 		ldBuildmode = "c-shared"
@@ -394,6 +325,9 @@
 		pkgsFilter = pkgsMain
 		ldBuildmode = "exe"
 	case "pie":
+		if cfg.BuildRace {
+			base.Fatalf("-buildmode=pie not supported when -race is enabled")
+		}
 		if gccgo {
 			codegenArg = "-fPIE"
 		} else {
@@ -402,7 +336,7 @@
 				"android/amd64", "android/arm", "android/arm64", "android/386":
 				codegenArg = "-shared"
 			default:
-				fatalf("-buildmode=pie not supported on %s\n", platform)
+				base.Fatalf("-buildmode=pie not supported on %s\n", platform)
 			}
 		}
 		ldBuildmode = "pie"
@@ -414,33 +348,33 @@
 			switch platform {
 			case "linux/386", "linux/amd64", "linux/arm", "linux/arm64", "linux/ppc64le", "linux/s390x":
 			default:
-				fatalf("-buildmode=shared not supported on %s\n", platform)
+				base.Fatalf("-buildmode=shared not supported on %s\n", platform)
 			}
 			codegenArg = "-dynlink"
 		}
-		if *buildO != "" {
-			fatalf("-buildmode=shared and -o not supported together")
+		if cfg.BuildO != "" {
+			base.Fatalf("-buildmode=shared and -o not supported together")
 		}
 		ldBuildmode = "shared"
 	case "plugin":
-		pkgsFilter = pkgsMain
+		pkgsFilter = oneMainPkg
 		if gccgo {
 			codegenArg = "-fPIC"
 		} else {
 			switch platform {
-			case "linux/amd64", "linux/arm", "linux/arm64", "linux/386",
+			case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/s390x",
 				"android/amd64", "android/arm", "android/arm64", "android/386":
 			default:
-				fatalf("-buildmode=plugin not supported on %s\n", platform)
+				base.Fatalf("-buildmode=plugin not supported on %s\n", platform)
 			}
 			codegenArg = "-dynlink"
 		}
-		exeSuffix = ".so"
+		cfg.ExeSuffix = ".so"
 		ldBuildmode = "plugin"
 	default:
-		fatalf("buildmode=%s not supported", buildBuildmode)
+		base.Fatalf("buildmode=%s not supported", cfg.BuildBuildmode)
 	}
-	if buildLinkshared {
+	if cfg.BuildLinkshared {
 		if gccgo {
 			codegenArg = "-fPIC"
 		} else {
@@ -448,55 +382,60 @@
 			case "linux/386", "linux/amd64", "linux/arm", "linux/arm64", "linux/ppc64le", "linux/s390x":
 				buildAsmflags = append(buildAsmflags, "-D=GOBUILDMODE_shared=1")
 			default:
-				fatalf("-linkshared not supported on %s\n", platform)
+				base.Fatalf("-linkshared not supported on %s\n", platform)
 			}
 			codegenArg = "-dynlink"
 			// TODO(mwhudson): remove -w when that gets fixed in linker.
-			buildLdflags = append(buildLdflags, "-linkshared", "-w")
+			cfg.BuildLdflags = append(cfg.BuildLdflags, "-linkshared", "-w")
 		}
 	}
 	if codegenArg != "" {
 		if gccgo {
-			buildGccgoflags = append(buildGccgoflags, codegenArg)
+			buildGccgoflags = append([]string{codegenArg}, buildGccgoflags...)
 		} else {
-			buildAsmflags = append(buildAsmflags, codegenArg)
-			buildGcflags = append(buildGcflags, codegenArg)
+			buildAsmflags = append([]string{codegenArg}, buildAsmflags...)
+			buildGcflags = append([]string{codegenArg}, buildGcflags...)
 		}
 		// Don't alter InstallSuffix when modifying default codegen args.
-		if buildBuildmode != "default" || buildLinkshared {
-			if buildContext.InstallSuffix != "" {
-				buildContext.InstallSuffix += "_"
+		if cfg.BuildBuildmode != "default" || cfg.BuildLinkshared {
+			if cfg.BuildContext.InstallSuffix != "" {
+				cfg.BuildContext.InstallSuffix += "_"
 			}
-			buildContext.InstallSuffix += codegenArg[1:]
+			cfg.BuildContext.InstallSuffix += codegenArg[1:]
 		}
 	}
+	if strings.HasPrefix(runtimeVersion, "go1") && !strings.Contains(os.Args[0], "go_bootstrap") && !gccgo {
+		buildGcflags = append(buildGcflags, "-goversion", runtimeVersion)
+	}
 }
 
-func runBuild(cmd *Command, args []string) {
-	instrumentInit()
-	buildModeInit()
-	var b builder
-	b.init()
+var runtimeVersion = runtime.Version()
 
-	pkgs := packagesForBuild(args)
+func runBuild(cmd *base.Command, args []string) {
+	InstrumentInit()
+	BuildModeInit()
+	var b Builder
+	b.Init()
 
-	if len(pkgs) == 1 && pkgs[0].Name == "main" && *buildO == "" {
-		_, *buildO = path.Split(pkgs[0].ImportPath)
-		*buildO += exeSuffix
+	pkgs := load.PackagesForBuild(args)
+
+	if len(pkgs) == 1 && pkgs[0].Name == "main" && cfg.BuildO == "" {
+		_, cfg.BuildO = path.Split(pkgs[0].ImportPath)
+		cfg.BuildO += cfg.ExeSuffix
 	}
 
 	// Special case -o /dev/null by not writing at all.
-	if *buildO == os.DevNull {
-		*buildO = ""
+	if cfg.BuildO == os.DevNull {
+		cfg.BuildO = ""
 	}
 
 	// sanity check some often mis-used options
-	switch buildContext.Compiler {
+	switch cfg.BuildContext.Compiler {
 	case "gccgo":
 		if len(buildGcflags) != 0 {
 			fmt.Println("go build: when using gccgo toolchain, please pass compiler flags using -gccgoflags, not -gcflags")
 		}
-		if len(buildLdflags) != 0 {
+		if len(cfg.BuildLdflags) != 0 {
 			fmt.Println("go build: when using gccgo toolchain, please pass linker flags using -gccgoflags, not -ldflags")
 		}
 	case "gc":
@@ -505,44 +444,45 @@
 		}
 	}
 
-	depMode := modeBuild
-	if buildI {
-		depMode = modeInstall
+	depMode := ModeBuild
+	if cfg.BuildI {
+		depMode = ModeInstall
 	}
 
-	if *buildO != "" {
+	if cfg.BuildO != "" {
 		if len(pkgs) > 1 {
-			fatalf("go build: cannot use -o with multiple packages")
+			base.Fatalf("go build: cannot use -o with multiple packages")
 		} else if len(pkgs) == 0 {
-			fatalf("no packages to build")
+			base.Fatalf("no packages to build")
 		}
 		p := pkgs[0]
-		p.target = *buildO
+		p.Internal.Target = cfg.BuildO
 		p.Stale = true // must build - not up to date
 		p.StaleReason = "build -o flag in use"
-		a := b.action(modeInstall, depMode, p)
-		b.do(a)
+		a := b.Action(ModeInstall, depMode, p)
+		b.Do(a)
 		return
 	}
 
-	var a *action
-	if buildBuildmode == "shared" {
-		pkgs := pkgsFilter(packages(args))
+	pkgs = pkgsFilter(load.Packages(args))
+
+	var a *Action
+	if cfg.BuildBuildmode == "shared" {
 		if libName, err := libname(args, pkgs); err != nil {
-			fatalf("%s", err.Error())
+			base.Fatalf("%s", err.Error())
 		} else {
-			a = b.libaction(libName, pkgs, modeBuild, depMode)
+			a = b.libaction(libName, pkgs, ModeBuild, depMode)
 		}
 	} else {
-		a = &action{}
-		for _, p := range pkgsFilter(packages(args)) {
-			a.deps = append(a.deps, b.action(modeBuild, depMode, p))
+		a = &Action{}
+		for _, p := range pkgs {
+			a.Deps = append(a.Deps, b.Action(ModeBuild, depMode, p))
 		}
 	}
-	b.do(a)
+	b.Do(a)
 }
 
-var cmdInstall = &Command{
+var CmdInstall = &base.Command{
 	UsageLine: "install [build flags] [packages]",
 	Short:     "compile and install packages and dependencies",
 	Long: `
@@ -556,11 +496,6 @@
 	`,
 }
 
-// isMetaPackage checks if name is a reserved package name that expands to multiple packages
-func isMetaPackage(name string) bool {
-	return name == "std" || name == "cmd" || name == "all"
-}
-
 // libname returns the filename to use for the shared library when using
 // -buildmode=shared. The rules we use are:
 // Use arguments for special 'meta' packages:
@@ -575,7 +510,7 @@
 //	gopkg.in/tomb.v2 -> libgopkg.in-tomb.v2.so
 //	a/... b/... ---> liba/c,b/d.so - all matching import paths
 // Name parts are joined with ','.
-func libname(args []string, pkgs []*Package) (string, error) {
+func libname(args []string, pkgs []*load.Package) (string, error) {
 	var libname string
 	appendName := func(arg string) {
 		if libname == "" {
@@ -586,7 +521,7 @@
 	}
 	var haveNonMeta bool
 	for _, arg := range args {
-		if isMetaPackage(arg) {
+		if load.IsMetaPackage(arg) {
 			appendName(arg)
 		} else {
 			haveNonMeta = true
@@ -598,7 +533,7 @@
 			arg := strings.TrimSuffix(args[0], "/...")
 			if build.IsLocalImport(arg) {
 				cwd, _ := os.Getwd()
-				bp, _ := buildContext.ImportDir(filepath.Join(cwd, arg), build.FindOnly)
+				bp, _ := cfg.BuildContext.ImportDir(filepath.Join(cwd, arg), build.FindOnly)
 				if bp.ImportPath != "" && bp.ImportPath != "." {
 					arg = bp.ImportPath
 				}
@@ -617,73 +552,76 @@
 	return "lib" + libname + ".so", nil
 }
 
-func runInstall(cmd *Command, args []string) {
-	installPackages(args, false)
+func runInstall(cmd *base.Command, args []string) {
+	InstrumentInit()
+	BuildModeInit()
+	InstallPackages(args, false)
 }
 
-func installPackages(args []string, forGet bool) {
-	if gobin != "" && !filepath.IsAbs(gobin) {
-		fatalf("cannot install, GOBIN must be an absolute path")
+func InstallPackages(args []string, forGet bool) {
+	if cfg.GOBIN != "" && !filepath.IsAbs(cfg.GOBIN) {
+		base.Fatalf("cannot install, GOBIN must be an absolute path")
 	}
 
-	instrumentInit()
-	buildModeInit()
-	pkgs := pkgsFilter(packagesForBuild(args))
+	pkgs := pkgsFilter(load.PackagesForBuild(args))
 
 	for _, p := range pkgs {
 		if p.Target == "" && (!p.Standard || p.ImportPath != "unsafe") {
 			switch {
-			case p.gobinSubdir:
-				errorf("go install: cannot install cross-compiled binaries when GOBIN is set")
-			case p.cmdline:
-				errorf("go install: no install location for .go files listed on command line (GOBIN not set)")
+			case p.Internal.GobinSubdir:
+				base.Errorf("go install: cannot install cross-compiled binaries when GOBIN is set")
+			case p.Internal.Cmdline:
+				base.Errorf("go install: no install location for .go files listed on command line (GOBIN not set)")
 			case p.ConflictDir != "":
-				errorf("go install: no install location for %s: hidden by %s", p.Dir, p.ConflictDir)
+				base.Errorf("go install: no install location for %s: hidden by %s", p.Dir, p.ConflictDir)
 			default:
-				errorf("go install: no install location for directory %s outside GOPATH\n"+
+				base.Errorf("go install: no install location for directory %s outside GOPATH\n"+
 					"\tFor more details see: 'go help gopath'", p.Dir)
 			}
 		}
 	}
-	exitIfErrors()
+	base.ExitIfErrors()
 
-	var b builder
-	b.init()
-	// Set the behavior for `go get` to not error on packages with test files only.
-	b.testFilesOnlyOK = forGet
-	var a *action
-	if buildBuildmode == "shared" {
+	var b Builder
+	b.Init()
+	var a *Action
+	if cfg.BuildBuildmode == "shared" {
 		if libName, err := libname(args, pkgs); err != nil {
-			fatalf("%s", err.Error())
+			base.Fatalf("%s", err.Error())
 		} else {
-			a = b.libaction(libName, pkgs, modeInstall, modeInstall)
+			a = b.libaction(libName, pkgs, ModeInstall, ModeInstall)
 		}
 	} else {
-		a = &action{}
-		var tools []*action
+		a = &Action{}
+		var tools []*Action
 		for _, p := range pkgs {
+			// During 'go get', don't attempt (and fail) to install packages with only tests.
+			// TODO(rsc): It's not clear why 'go get' should be different from 'go install' here. See #20760.
+			if forGet && len(p.GoFiles)+len(p.CgoFiles) == 0 && len(p.TestGoFiles)+len(p.XTestGoFiles) > 0 {
+				continue
+			}
 			// If p is a tool, delay the installation until the end of the build.
 			// This avoids installing assemblers/compilers that are being executed
 			// by other steps in the build.
-			// cmd/cgo is handled specially in b.action, so that we can
+			// cmd/cgo is handled specially in b.Action, so that we can
 			// both build and use it in the same 'go install'.
-			action := b.action(modeInstall, modeInstall, p)
-			if goTools[p.ImportPath] == toTool && p.ImportPath != "cmd/cgo" {
-				a.deps = append(a.deps, action.deps...)
-				action.deps = append(action.deps, a)
-				tools = append(tools, action)
+			Action := b.Action(ModeInstall, ModeInstall, p)
+			if load.GoTools[p.ImportPath] == load.ToTool && p.ImportPath != "cmd/cgo" {
+				a.Deps = append(a.Deps, Action.Deps...)
+				Action.Deps = append(Action.Deps, a)
+				tools = append(tools, Action)
 				continue
 			}
-			a.deps = append(a.deps, action)
+			a.Deps = append(a.Deps, Action)
 		}
 		if len(tools) > 0 {
-			a = &action{
-				deps: tools,
+			a = &Action{
+				Deps: tools,
 			}
 		}
 	}
-	b.do(a)
-	exitIfErrors()
+	b.Do(a)
+	base.ExitIfErrors()
 
 	// Success. If this command is 'go install' with no arguments
 	// and the current directory (the implicit argument) is a command,
@@ -698,13 +636,13 @@
 		// Compute file 'go build' would have created.
 		// If it exists and is an executable file, remove it.
 		_, targ := filepath.Split(pkgs[0].ImportPath)
-		targ += exeSuffix
+		targ += cfg.ExeSuffix
 		if filepath.Join(pkgs[0].Dir, targ) != pkgs[0].Target { // maybe $GOBIN is the current directory
 			fi, err := os.Stat(targ)
 			if err == nil {
 				m := fi.Mode()
 				if m.IsRegular() {
-					if m&0111 != 0 || goos == "windows" { // windows never sets executable bit
+					if m&0111 != 0 || cfg.Goos == "windows" { // windows never sets executable bit
 						os.Remove(targ)
 					}
 				}
@@ -713,35 +651,15 @@
 	}
 }
 
-// Global build parameters (used during package load)
-var (
-	goarch    string
-	goos      string
-	exeSuffix string
-	gopath    []string
-)
-
-func init() {
-	goarch = buildContext.GOARCH
-	goos = buildContext.GOOS
-
-	if goos == "windows" {
-		exeSuffix = ".exe"
-	}
-	gopath = filepath.SplitList(buildContext.GOPATH)
-}
-
-// A builder holds global state about a build.
+// A Builder holds global state about a build.
 // It does not hold per-package state, because we
 // build packages in parallel, and the builder is shared.
-type builder struct {
-	work        string               // the temporary work directory (ends in filepath.Separator)
-	actionCache map[cacheKey]*action // a cache of already-constructed actions
+type Builder struct {
+	WorkDir     string               // the temporary work directory (ends in filepath.Separator)
+	actionCache map[cacheKey]*Action // a cache of already-constructed actions
 	mkdirCache  map[string]bool      // a cache of created directories
 	flagCache   map[string]bool      // a cache of supported compiler flags
-	print       func(args ...interface{}) (int, error)
-
-	testFilesOnlyOK bool // do not error if the packages only have test files
+	Print       func(args ...interface{}) (int, error)
 
 	output    sync.Mutex
 	scriptDir string // current directory in printed script
@@ -751,168 +669,82 @@
 	ready     actionQueue
 }
 
-// An action represents a single action in the action graph.
-type action struct {
-	p          *Package      // the package this action works on
-	deps       []*action     // actions that must happen before this one
-	triggers   []*action     // inverse of deps
-	cgo        *action       // action for cgo binary if needed
-	args       []string      // additional args for runProgram
-	testOutput *bytes.Buffer // test output buffer
+// NOTE: Much of Action would not need to be exported if not for test.
+// Maybe test functionality should move into this package too?
 
-	f          func(*builder, *action) error // the action itself (nil = no-op)
-	ignoreFail bool                          // whether to run f even if dependencies fail
+// An Action represents a single action in the action graph.
+type Action struct {
+	Package    *load.Package                 // the package this action works on
+	Deps       []*Action                     // actions that must happen before this one
+	Func       func(*Builder, *Action) error // the action itself (nil = no-op)
+	IgnoreFail bool                          // whether to run f even if dependencies fail
+	TestOutput *bytes.Buffer                 // test output buffer
+	Args       []string                      // additional args for runProgram
+
+	triggers []*Action // inverse of deps
+	cgo      *Action   // action for cgo binary if needed
 
 	// Generated files, directories.
-	link   bool   // target is executable, not just package
-	pkgdir string // the -I or -L argument to use when importing this package
-	objdir string // directory for intermediate objects
-	objpkg string // the intermediate package .a file created during the action
-	target string // goal of the action: the created package or executable
+	Link   bool   // target is executable, not just package
+	Pkgdir string // the -I or -L argument to use when importing this package
+	Objdir string // directory for intermediate objects
+	Objpkg string // the intermediate package .a file created during the action
+	Target string // goal of the action: the created package or executable
 
 	// Execution state.
 	pending  int  // number of deps yet to complete
 	priority int  // relative execution priority
-	failed   bool // whether the action failed
+	Failed   bool // whether the action failed
 }
 
 // cacheKey is the key for the action cache.
 type cacheKey struct {
-	mode  buildMode
-	p     *Package
+	mode  BuildMode
+	p     *load.Package
 	shlib string
 }
 
-// buildMode specifies the build mode:
+// BuildMode specifies the build mode:
 // are we just building things or also installing the results?
-type buildMode int
+type BuildMode int
 
 const (
-	modeBuild buildMode = iota
-	modeInstall
+	ModeBuild BuildMode = iota
+	ModeInstall
 )
 
-var (
-	goroot    = filepath.Clean(runtime.GOROOT())
-	gobin     = os.Getenv("GOBIN")
-	gorootBin = filepath.Join(goroot, "bin")
-	gorootPkg = filepath.Join(goroot, "pkg")
-	gorootSrc = filepath.Join(goroot, "src")
-)
-
-func (b *builder) init() {
+func (b *Builder) Init() {
 	var err error
-	b.print = func(a ...interface{}) (int, error) {
+	b.Print = func(a ...interface{}) (int, error) {
 		return fmt.Fprint(os.Stderr, a...)
 	}
-	b.actionCache = make(map[cacheKey]*action)
+	b.actionCache = make(map[cacheKey]*Action)
 	b.mkdirCache = make(map[string]bool)
 
-	if buildN {
-		b.work = "$WORK"
+	if cfg.BuildN {
+		b.WorkDir = "$WORK"
 	} else {
-		b.work, err = ioutil.TempDir("", "go-build")
+		b.WorkDir, err = ioutil.TempDir("", "go-build")
 		if err != nil {
-			fatalf("%s", err)
+			base.Fatalf("%s", err)
 		}
-		if buildX || buildWork {
-			fmt.Fprintf(os.Stderr, "WORK=%s\n", b.work)
+		if cfg.BuildX || cfg.BuildWork {
+			fmt.Fprintf(os.Stderr, "WORK=%s\n", b.WorkDir)
 		}
-		if !buildWork {
-			workdir := b.work
-			atexit(func() { os.RemoveAll(workdir) })
+		if !cfg.BuildWork {
+			workdir := b.WorkDir
+			base.AtExit(func() { os.RemoveAll(workdir) })
 		}
 	}
 }
 
-// goFilesPackage creates a package for building a collection of Go files
-// (typically named on the command line).  The target is named p.a for
-// package p or named after the first Go file for package main.
-func goFilesPackage(gofiles []string) *Package {
-	// TODO: Remove this restriction.
-	for _, f := range gofiles {
-		if !strings.HasSuffix(f, ".go") {
-			fatalf("named files must be .go files")
-		}
-	}
-
-	var stk importStack
-	ctxt := buildContext
-	ctxt.UseAllFiles = true
-
-	// Synthesize fake "directory" that only shows the named files,
-	// to make it look like this is a standard package or
-	// command directory. So that local imports resolve
-	// consistently, the files must all be in the same directory.
-	var dirent []os.FileInfo
-	var dir string
-	for _, file := range gofiles {
-		fi, err := os.Stat(file)
-		if err != nil {
-			fatalf("%s", err)
-		}
-		if fi.IsDir() {
-			fatalf("%s is a directory, should be a Go file", file)
-		}
-		dir1, _ := filepath.Split(file)
-		if dir1 == "" {
-			dir1 = "./"
-		}
-		if dir == "" {
-			dir = dir1
-		} else if dir != dir1 {
-			fatalf("named files must all be in one directory; have %s and %s", dir, dir1)
-		}
-		dirent = append(dirent, fi)
-	}
-	ctxt.ReadDir = func(string) ([]os.FileInfo, error) { return dirent, nil }
-
-	var err error
-	if dir == "" {
-		dir = cwd
-	}
-	dir, err = filepath.Abs(dir)
-	if err != nil {
-		fatalf("%s", err)
-	}
-
-	bp, err := ctxt.ImportDir(dir, 0)
-	pkg := new(Package)
-	pkg.local = true
-	pkg.cmdline = true
-	stk.push("main")
-	pkg.load(&stk, bp, err)
-	stk.pop()
-	pkg.localPrefix = dirToImportPath(dir)
-	pkg.ImportPath = "command-line-arguments"
-	pkg.target = ""
-
-	if pkg.Name == "main" {
-		_, elem := filepath.Split(gofiles[0])
-		exe := elem[:len(elem)-len(".go")] + exeSuffix
-		if *buildO == "" {
-			*buildO = exe
-		}
-		if gobin != "" {
-			pkg.target = filepath.Join(gobin, exe)
-		}
-	}
-
-	pkg.Target = pkg.target
-	pkg.Stale = true
-	pkg.StaleReason = "files named on command line"
-
-	computeStale(pkg)
-	return pkg
-}
-
 // readpkglist returns the list of packages that were built into the shared library
 // at shlibpath. For the native toolchain this list is stored, newline separated, in
 // an ELF note with name "Go\x00\x00" and type 1. For GCCGO it is extracted from the
 // .go_export section.
-func readpkglist(shlibpath string) (pkgs []*Package) {
-	var stk importStack
-	if _, gccgo := buildToolchain.(gccgoToolchain); gccgo {
+func readpkglist(shlibpath string) (pkgs []*load.Package) {
+	var stk load.ImportStack
+	if cfg.BuildToolchainName == "gccgo" {
 		f, _ := elf.Open(shlibpath)
 		sect := f.Section(".go_export")
 		data, _ := sect.Data()
@@ -922,28 +754,28 @@
 			if strings.HasPrefix(t, "pkgpath ") {
 				t = strings.TrimPrefix(t, "pkgpath ")
 				t = strings.TrimSuffix(t, ";")
-				pkgs = append(pkgs, loadPackage(t, &stk))
+				pkgs = append(pkgs, load.LoadPackage(t, &stk))
 			}
 		}
 	} else {
-		pkglistbytes, err := readELFNote(shlibpath, "Go\x00\x00", 1)
+		pkglistbytes, err := buildid.ReadELFNote(shlibpath, "Go\x00\x00", 1)
 		if err != nil {
-			fatalf("readELFNote failed: %v", err)
+			base.Fatalf("readELFNote failed: %v", err)
 		}
 		scanner := bufio.NewScanner(bytes.NewBuffer(pkglistbytes))
 		for scanner.Scan() {
 			t := scanner.Text()
-			pkgs = append(pkgs, loadPackage(t, &stk))
+			pkgs = append(pkgs, load.LoadPackage(t, &stk))
 		}
 	}
 	return
 }
 
-// action returns the action for applying the given operation (mode) to the package.
+// Action returns the action for applying the given operation (mode) to the package.
 // depMode is the action to use when building dependencies.
 // action never looks for p in a shared library, but may find p's dependencies in a
 // shared library if buildLinkshared is true.
-func (b *builder) action(mode buildMode, depMode buildMode, p *Package) *action {
+func (b *Builder) Action(mode BuildMode, depMode BuildMode, p *load.Package) *Action {
 	return b.action1(mode, depMode, p, false, "")
 }
 
@@ -951,7 +783,7 @@
 // depMode is the action to use when building dependencies.
 // action1 will look for p in a shared library if lookshared is true.
 // forShlib is the shared library that p will become part of, if any.
-func (b *builder) action1(mode buildMode, depMode buildMode, p *Package, lookshared bool, forShlib string) *action {
+func (b *Builder) action1(mode BuildMode, depMode BuildMode, p *load.Package, lookshared bool, forShlib string) *Action {
 	shlib := ""
 	if lookshared {
 		shlib = p.Shlib
@@ -963,42 +795,42 @@
 		return a
 	}
 	if shlib != "" {
-		key2 := cacheKey{modeInstall, nil, shlib}
+		key2 := cacheKey{ModeInstall, nil, shlib}
 		a = b.actionCache[key2]
 		if a != nil {
 			b.actionCache[key] = a
 			return a
 		}
 		pkgs := readpkglist(shlib)
-		a = b.libaction(filepath.Base(shlib), pkgs, modeInstall, depMode)
+		a = b.libaction(filepath.Base(shlib), pkgs, ModeInstall, depMode)
 		b.actionCache[key2] = a
 		b.actionCache[key] = a
 		return a
 	}
 
-	a = &action{p: p, pkgdir: p.build.PkgRoot}
-	if p.pkgdir != "" { // overrides p.t
-		a.pkgdir = p.pkgdir
+	a = &Action{Package: p, Pkgdir: p.Internal.Build.PkgRoot}
+	if p.Internal.Pkgdir != "" { // overrides p.t
+		a.Pkgdir = p.Internal.Pkgdir
 	}
 	b.actionCache[key] = a
 
-	for _, p1 := range p.imports {
+	for _, p1 := range p.Internal.Imports {
 		if forShlib != "" {
 			// p is part of a shared library.
 			if p1.Shlib != "" && p1.Shlib != forShlib {
 				// p1 is explicitly part of a different shared library.
-				// Put the action for that shared library into a.deps.
-				a.deps = append(a.deps, b.action1(depMode, depMode, p1, true, p1.Shlib))
+				// Put the action for that shared library into a.Deps.
+				a.Deps = append(a.Deps, b.action1(depMode, depMode, p1, true, p1.Shlib))
 			} else {
 				// p1 is (implicitly or not) part of this shared library.
-				// Put the action for p1 into a.deps.
-				a.deps = append(a.deps, b.action1(depMode, depMode, p1, false, forShlib))
+				// Put the action for p1 into a.Deps.
+				a.Deps = append(a.Deps, b.action1(depMode, depMode, p1, false, forShlib))
 			}
 		} else {
 			// p is not part of a shared library.
 			// If p1 is in a shared library, put the action for that into
-			// a.deps, otherwise put the action for p1 into a.deps.
-			a.deps = append(a.deps, b.action1(depMode, depMode, p1, buildLinkshared, p1.Shlib))
+			// a.Deps, otherwise put the action for p1 into a.Deps.
+			a.Deps = append(a.Deps, b.action1(depMode, depMode, p1, cfg.BuildLinkshared, p1.Shlib))
 		}
 	}
 
@@ -1007,15 +839,15 @@
 	// using cgo, to make sure we do not overwrite the binary while
 	// a package is using it. If this is a cross-build, then the cgo we
 	// are writing is not the cgo we need to use.
-	if goos == runtime.GOOS && goarch == runtime.GOARCH && !buildRace && !buildMSan && reqStdPkgSrc {
-		if (len(p.CgoFiles) > 0 || p.Standard && p.ImportPath == "runtime/cgo") && !buildLinkshared && buildBuildmode != "shared" {
-			var stk importStack
-			p1 := loadPackage("cmd/cgo", &stk)
+	if cfg.Goos == runtime.GOOS && cfg.Goarch == runtime.GOARCH && !cfg.BuildRace && !cfg.BuildMSan && cfg.BuildToolchainName != "gccgo" {
+		if (len(p.CgoFiles) > 0 || p.Standard && p.ImportPath == "runtime/cgo") && !cfg.BuildLinkshared && cfg.BuildBuildmode != "shared" {
+			var stk load.ImportStack
+			p1 := load.LoadPackage("cmd/cgo", &stk)
 			if p1.Error != nil {
-				fatalf("load cmd/cgo: %v", p1.Error)
+				base.Fatalf("load cmd/cgo: %v", p1.Error)
 			}
-			a.cgo = b.action(depMode, depMode, p1)
-			a.deps = append(a.deps, a.cgo)
+			a.cgo = b.Action(depMode, depMode, p1)
+			a.Deps = append(a.Deps, a.cgo)
 		}
 	}
 
@@ -1026,42 +858,42 @@
 			return a
 		}
 		// gccgo standard library is "fake" too.
-		if _, ok := buildToolchain.(gccgoToolchain); ok {
+		if cfg.BuildToolchainName == "gccgo" {
 			// the target name is needed for cgo.
-			a.target = p.target
+			a.Target = p.Internal.Target
 			return a
 		}
 	}
 
-	if !p.Stale && p.target != "" {
-		// p.Stale==false implies that p.target is up-to-date.
+	if !p.Stale && p.Internal.Target != "" {
+		// p.Stale==false implies that p.Internal.Target is up-to-date.
 		// Record target name for use by actions depending on this one.
-		a.target = p.target
+		a.Target = p.Internal.Target
 		return a
 	}
 
-	if p.local && p.target == "" {
+	if p.Internal.Local && p.Internal.Target == "" {
 		// Imported via local path. No permanent target.
-		mode = modeBuild
+		mode = ModeBuild
 	}
-	work := p.pkgdir
+	work := p.Internal.Pkgdir
 	if work == "" {
-		work = b.work
+		work = b.WorkDir
 	}
-	a.objdir = filepath.Join(work, a.p.ImportPath, "_obj") + string(filepath.Separator)
-	a.objpkg = buildToolchain.pkgpath(work, a.p)
-	a.link = p.Name == "main"
+	a.Objdir = filepath.Join(work, a.Package.ImportPath, "_obj") + string(filepath.Separator)
+	a.Objpkg = BuildToolchain.Pkgpath(work, a.Package)
+	a.Link = p.Name == "main"
 
 	switch mode {
-	case modeInstall:
-		a.f = (*builder).install
-		a.deps = []*action{b.action1(modeBuild, depMode, p, lookshared, forShlib)}
-		a.target = a.p.target
+	case ModeInstall:
+		a.Func = BuildInstallFunc
+		a.Deps = []*Action{b.action1(ModeBuild, depMode, p, lookshared, forShlib)}
+		a.Target = a.Package.Internal.Target
 
 		// Install header for cgo in c-archive and c-shared modes.
-		if p.usesCgo() && (buildBuildmode == "c-archive" || buildBuildmode == "c-shared") {
-			hdrTarget := a.target[:len(a.target)-len(filepath.Ext(a.target))] + ".h"
-			if buildContext.Compiler == "gccgo" && *buildO == "" {
+		if p.UsesCgo() && (cfg.BuildBuildmode == "c-archive" || cfg.BuildBuildmode == "c-shared") {
+			hdrTarget := a.Target[:len(a.Target)-len(filepath.Ext(a.Target))] + ".h"
+			if cfg.BuildContext.Compiler == "gccgo" && cfg.BuildO == "" {
 				// For the header file, remove the "lib"
 				// added by go/build, so we generate pkg.h
 				// rather than libpkg.h.
@@ -1069,21 +901,21 @@
 				file = strings.TrimPrefix(file, "lib")
 				hdrTarget = filepath.Join(dir, file)
 			}
-			ah := &action{
-				p:      a.p,
-				deps:   []*action{a.deps[0]},
-				f:      (*builder).installHeader,
-				pkgdir: a.pkgdir,
-				objdir: a.objdir,
-				target: hdrTarget,
+			ah := &Action{
+				Package: a.Package,
+				Deps:    []*Action{a.Deps[0]},
+				Func:    (*Builder).installHeader,
+				Pkgdir:  a.Pkgdir,
+				Objdir:  a.Objdir,
+				Target:  hdrTarget,
 			}
-			a.deps = append(a.deps, ah)
+			a.Deps = append(a.Deps, ah)
 		}
 
-	case modeBuild:
-		a.f = (*builder).build
-		a.target = a.objpkg
-		if a.link {
+	case ModeBuild:
+		a.Func = (*Builder).build
+		a.Target = a.Objpkg
+		if a.Link {
 			// An executable file. (This is the name of a temporary file.)
 			// Because we run the temporary file in 'go run' and 'go test',
 			// the name will show up in ps listings. If the caller has specified
@@ -1092,84 +924,84 @@
 			// naming conflicts. The only possible conflict is if we were
 			// to create a top-level package named exe.
 			name := "a.out"
-			if p.exeName != "" {
-				name = p.exeName
-			} else if goos == "darwin" && buildBuildmode == "c-shared" && p.target != "" {
+			if p.Internal.ExeName != "" {
+				name = p.Internal.ExeName
+			} else if cfg.Goos == "darwin" && cfg.BuildBuildmode == "c-shared" && p.Internal.Target != "" {
 				// On OS X, the linker output name gets recorded in the
 				// shared library's LC_ID_DYLIB load command.
 				// The code invoking the linker knows to pass only the final
 				// path element. Arrange that the path element matches what
 				// we'll install it as; otherwise the library is only loadable as "a.out".
-				_, name = filepath.Split(p.target)
+				_, name = filepath.Split(p.Internal.Target)
 			}
-			a.target = a.objdir + filepath.Join("exe", name) + exeSuffix
+			a.Target = a.Objdir + filepath.Join("exe", name) + cfg.ExeSuffix
 		}
 	}
 
 	return a
 }
 
-func (b *builder) libaction(libname string, pkgs []*Package, mode, depMode buildMode) *action {
-	a := &action{}
+func (b *Builder) libaction(libname string, pkgs []*load.Package, mode, depMode BuildMode) *Action {
+	a := &Action{}
 	switch mode {
 	default:
-		fatalf("unrecognized mode %v", mode)
+		base.Fatalf("unrecognized mode %v", mode)
 
-	case modeBuild:
-		a.f = (*builder).linkShared
-		a.target = filepath.Join(b.work, libname)
+	case ModeBuild:
+		a.Func = (*Builder).linkShared
+		a.Target = filepath.Join(b.WorkDir, libname)
 		for _, p := range pkgs {
-			if p.target == "" {
+			if p.Internal.Target == "" {
 				continue
 			}
-			a.deps = append(a.deps, b.action(depMode, depMode, p))
+			a.Deps = append(a.Deps, b.Action(depMode, depMode, p))
 		}
 
-	case modeInstall:
+	case ModeInstall:
 		// Currently build mode shared forces external linking mode, and
 		// external linking mode forces an import of runtime/cgo (and
 		// math on arm). So if it was not passed on the command line and
 		// it is not present in another shared library, add it here.
-		_, gccgo := buildToolchain.(gccgoToolchain)
+		gccgo := cfg.BuildToolchainName == "gccgo"
 		if !gccgo {
 			seencgo := false
 			for _, p := range pkgs {
 				seencgo = seencgo || (p.Standard && p.ImportPath == "runtime/cgo")
 			}
 			if !seencgo {
-				var stk importStack
-				p := loadPackage("runtime/cgo", &stk)
+				var stk load.ImportStack
+				p := load.LoadPackage("runtime/cgo", &stk)
 				if p.Error != nil {
-					fatalf("load runtime/cgo: %v", p.Error)
+					base.Fatalf("load runtime/cgo: %v", p.Error)
 				}
-				computeStale(p)
+				load.ComputeStale(p)
 				// If runtime/cgo is in another shared library, then that's
 				// also the shared library that contains runtime, so
 				// something will depend on it and so runtime/cgo's staleness
 				// will be checked when processing that library.
 				if p.Shlib == "" || p.Shlib == libname {
-					pkgs = append([]*Package{}, pkgs...)
+					pkgs = append([]*load.Package{}, pkgs...)
 					pkgs = append(pkgs, p)
 				}
 			}
-			if goarch == "arm" {
+			if cfg.Goarch == "arm" {
 				seenmath := false
 				for _, p := range pkgs {
 					seenmath = seenmath || (p.Standard && p.ImportPath == "math")
 				}
 				if !seenmath {
-					var stk importStack
-					p := loadPackage("math", &stk)
+					var stk load.ImportStack
+					p := load.LoadPackage("math", &stk)
 					if p.Error != nil {
-						fatalf("load math: %v", p.Error)
+						base.Fatalf("load math: %v", p.Error)
 					}
-					computeStale(p)
+					load.ComputeStale(p)
 					// If math is in another shared library, then that's
 					// also the shared library that contains runtime, so
 					// something will depend on it and so math's staleness
 					// will be checked when processing that library.
 					if p.Shlib == "" || p.Shlib == libname {
-						pkgs = append([]*Package{}, pkgs...)
+						pkgs = append([]*load.Package{}, pkgs...)
 						pkgs = append(pkgs, p)
 					}
 				}
@@ -1179,67 +1011,67 @@
 		// Figure out where the library will go.
 		var libdir string
 		for _, p := range pkgs {
-			plibdir := p.build.PkgTargetRoot
+			plibdir := p.Internal.Build.PkgTargetRoot
 			if gccgo {
 				plibdir = filepath.Join(plibdir, "shlibs")
 			}
 			if libdir == "" {
 				libdir = plibdir
 			} else if libdir != plibdir {
-				fatalf("multiple roots %s & %s", libdir, plibdir)
+				base.Fatalf("multiple roots %s & %s", libdir, plibdir)
 			}
 		}
-		a.target = filepath.Join(libdir, libname)
+		a.Target = filepath.Join(libdir, libname)
 
 		// Now we can check whether we need to rebuild it.
 		stale := false
 		var built time.Time
-		if fi, err := os.Stat(a.target); err == nil {
+		if fi, err := os.Stat(a.Target); err == nil {
 			built = fi.ModTime()
 		}
 		for _, p := range pkgs {
-			if p.target == "" {
+			if p.Internal.Target == "" {
 				continue
 			}
 			stale = stale || p.Stale
-			lstat, err := os.Stat(p.target)
+			lstat, err := os.Stat(p.Internal.Target)
 			if err != nil || lstat.ModTime().After(built) {
 				stale = true
 			}
-			a.deps = append(a.deps, b.action1(depMode, depMode, p, false, a.target))
+			a.Deps = append(a.Deps, b.action1(depMode, depMode, p, false, a.Target))
 		}
 
 		if stale {
-			a.f = (*builder).install
-			buildAction := b.libaction(libname, pkgs, modeBuild, depMode)
-			a.deps = []*action{buildAction}
+			a.Func = BuildInstallFunc
+			buildAction := b.libaction(libname, pkgs, ModeBuild, depMode)
+			a.Deps = []*Action{buildAction}
 			for _, p := range pkgs {
-				if p.target == "" {
+				if p.Internal.Target == "" {
 					continue
 				}
-				shlibnameaction := &action{}
-				shlibnameaction.f = (*builder).installShlibname
-				shlibnameaction.target = p.target[:len(p.target)-2] + ".shlibname"
-				a.deps = append(a.deps, shlibnameaction)
-				shlibnameaction.deps = append(shlibnameaction.deps, buildAction)
+				shlibnameaction := &Action{}
+				shlibnameaction.Func = (*Builder).installShlibname
+				shlibnameaction.Target = p.Internal.Target[:len(p.Internal.Target)-2] + ".shlibname"
+				a.Deps = append(a.Deps, shlibnameaction)
+				shlibnameaction.Deps = append(shlibnameaction.Deps, buildAction)
 			}
 		}
 	}
 	return a
 }
 
-// actionList returns the list of actions in the dag rooted at root
+// ActionList returns the list of actions in the dag rooted at root
 // as visited in a depth-first post-order traversal.
-func actionList(root *action) []*action {
-	seen := map[*action]bool{}
-	all := []*action{}
-	var walk func(*action)
-	walk = func(a *action) {
+func ActionList(root *Action) []*Action {
+	seen := map[*Action]bool{}
+	all := []*Action{}
+	var walk func(*Action)
+	walk = func(a *Action) {
 		if seen[a] {
 			return
 		}
 		seen[a] = true
-		for _, a1 := range a.deps {
+		for _, a1 := range a.Deps {
 			walk(a1)
 		}
 		all = append(all, a)
@@ -1252,20 +1084,20 @@
 // This is needed because if package p depends on package q that is in libr.so, the
 // action graph looks like p->libr.so->q and so just scanning through p's
 // dependencies does not find the import dir for q.
-func allArchiveActions(root *action) []*action {
-	seen := map[*action]bool{}
-	r := []*action{}
-	var walk func(*action)
-	walk = func(a *action) {
+func allArchiveActions(root *Action) []*Action {
+	seen := map[*Action]bool{}
+	r := []*Action{}
+	var walk func(*Action)
+	walk = func(a *Action) {
 		if seen[a] {
 			return
 		}
 		seen[a] = true
-		if strings.HasSuffix(a.target, ".so") || a == root {
-			for _, a1 := range a.deps {
+		if strings.HasSuffix(a.Target, ".so") || a == root {
+			for _, a1 := range a.Deps {
 				walk(a1)
 			}
-		} else if strings.HasSuffix(a.target, ".a") {
+		} else if strings.HasSuffix(a.Target, ".a") {
 			r = append(r, a)
 		}
 	}
@@ -1274,15 +1106,22 @@
 }
 
 // do runs the action graph rooted at root.
-func (b *builder) do(root *action) {
-	/* Commented out for gccgo, which does not have osArchSupportsCgo.
+func (b *Builder) Do(root *Action) {
+	/* Commented for gccgo, which does not have OSArchSupportsCgo.
 
-	if _, ok := osArchSupportsCgo[goos+"/"+goarch]; !ok && buildContext.Compiler == "gc" {
-		fmt.Fprintf(os.Stderr, "cmd/go: unsupported GOOS/GOARCH pair %s/%s\n", goos, goarch)
+	if _, ok := cfg.OSArchSupportsCgo[cfg.Goos+"/"+cfg.Goarch]; !ok && cfg.BuildContext.Compiler == "gc" {
+		fmt.Fprintf(os.Stderr, "cmd/go: unsupported GOOS/GOARCH pair %s/%s\n", cfg.Goos, cfg.Goarch)
 		os.Exit(2)
 	}
 	*/
 
+	for _, tag := range cfg.BuildContext.BuildTags {
+		if strings.Contains(tag, ",") {
+			fmt.Fprintf(os.Stderr, "cmd/go: -tags space-separated list contains comma\n")
+			os.Exit(2)
+		}
+	}
+
 	// Build list of all actions, assigning depth-first post-order priority.
 	// The original implementation here was a true queue
 	// (using a channel) but it had the effect of getting
@@ -1294,7 +1133,7 @@
 	// ensure that, all else being equal, the execution prefers
 	// to do what it would have done first in a simple depth-first
 	// dependency order traversal.
-	all := actionList(root)
+	all := ActionList(root)
 	for i, a := range all {
 		a.priority = i
 	}
@@ -1303,10 +1142,10 @@
 
 	// Initialize per-action execution state.
 	for _, a := range all {
-		for _, a1 := range a.deps {
+		for _, a1 := range a.Deps {
 			a1.triggers = append(a1.triggers, a)
 		}
-		a.pending = len(a.deps)
+		a.pending = len(a.Deps)
 		if a.pending == 0 {
 			b.ready.push(a)
 			b.readySema <- true
@@ -1315,10 +1154,10 @@
 
 	// Handle runs a single action and takes care of triggering
 	// any actions that are runnable as a result.
-	handle := func(a *action) {
+	handle := func(a *Action) {
 		var err error
-		if a.f != nil && (!a.failed || a.ignoreFail) {
-			err = a.f(b, a)
+		if a.Func != nil && (!a.Failed || a.IgnoreFail) {
+			err = a.Func(b, a)
 		}
 
 		// The actions run in parallel but all the updates to the
@@ -1328,18 +1167,16 @@
 
 		if err != nil {
 			if err == errPrintedOutput {
-				setExitStatus(2)
-			} else if _, ok := err.(*build.NoGoError); ok && len(a.p.TestGoFiles) > 0 && b.testFilesOnlyOK {
-				// Ignore the "no buildable Go source files" error for a package with only test files.
+				base.SetExitStatus(2)
 			} else {
-				errorf("%s", err)
+				base.Errorf("%s", err)
 			}
-			a.failed = true
+			a.Failed = true
 		}
 
 		for _, a0 := range a.triggers {
-			if a.failed {
-				a0.failed = true
+			if a.Failed {
+				a0.Failed = true
 			}
 			if a0.pending--; a0.pending == 0 {
 				b.ready.push(a0)
@@ -1358,8 +1195,8 @@
 	// If we are using the -n flag (just printing commands)
 	// drop the parallelism to 1, both to make the output
 	// deterministic and because there is no real work anyway.
-	par := buildP
-	if buildN {
+	par := cfg.BuildP
+	if cfg.BuildN {
 		par = 1
 	}
 	for i := 0; i < par; i++ {
@@ -1378,8 +1215,8 @@
 					a := b.ready.pop()
 					b.exec.Unlock()
 					handle(a)
-				case <-interrupted:
-					setExitStatus(1)
+				case <-base.Interrupted:
+					base.SetExitStatus(1)
 					return
 				}
 			}
@@ -1390,74 +1227,74 @@
 }
 
 // build is the action for building a single package or command.
-func (b *builder) build(a *action) (err error) {
+func (b *Builder) build(a *Action) (err error) {
 	// Return an error for binary-only package.
 	// We only reach this if isStale believes the binary form is
 	// either not present or not usable.
-	if a.p.BinaryOnly {
-		return fmt.Errorf("missing or invalid package binary for binary-only package %s", a.p.ImportPath)
+	if a.Package.BinaryOnly {
+		return fmt.Errorf("missing or invalid package binary for binary-only package %s", a.Package.ImportPath)
 	}
 
 	// Return an error if the package has CXX files but it's not using
 	// cgo nor SWIG, since the CXX files can only be processed by cgo
 	// and SWIG.
-	if len(a.p.CXXFiles) > 0 && !a.p.usesCgo() && !a.p.usesSwig() {
+	if len(a.Package.CXXFiles) > 0 && !a.Package.UsesCgo() && !a.Package.UsesSwig() {
 		return fmt.Errorf("can't build package %s because it contains C++ files (%s) but it's not using cgo nor SWIG",
-			a.p.ImportPath, strings.Join(a.p.CXXFiles, ","))
+			a.Package.ImportPath, strings.Join(a.Package.CXXFiles, ","))
 	}
 	// Same as above for Objective-C files
-	if len(a.p.MFiles) > 0 && !a.p.usesCgo() && !a.p.usesSwig() {
+	if len(a.Package.MFiles) > 0 && !a.Package.UsesCgo() && !a.Package.UsesSwig() {
 		return fmt.Errorf("can't build package %s because it contains Objective-C files (%s) but it's not using cgo nor SWIG",
-			a.p.ImportPath, strings.Join(a.p.MFiles, ","))
+			a.Package.ImportPath, strings.Join(a.Package.MFiles, ","))
 	}
 	// Same as above for Fortran files
-	if len(a.p.FFiles) > 0 && !a.p.usesCgo() && !a.p.usesSwig() {
+	if len(a.Package.FFiles) > 0 && !a.Package.UsesCgo() && !a.Package.UsesSwig() {
 		return fmt.Errorf("can't build package %s because it contains Fortran files (%s) but it's not using cgo nor SWIG",
-			a.p.ImportPath, strings.Join(a.p.FFiles, ","))
+			a.Package.ImportPath, strings.Join(a.Package.FFiles, ","))
 	}
 
 	defer func() {
-		if _, ok := err.(*build.NoGoError); err != nil && err != errPrintedOutput && !(ok && b.testFilesOnlyOK && len(a.p.TestGoFiles) > 0) {
-			err = fmt.Errorf("go build %s: %v", a.p.ImportPath, err)
+		if err != nil && err != errPrintedOutput {
+			err = fmt.Errorf("go build %s: %v", a.Package.ImportPath, err)
 		}
 	}()
-	if buildN {
+	if cfg.BuildN {
 		// In -n mode, print a banner between packages.
 		// The banner is five lines so that when changes to
 		// different sections of the bootstrap script have to
 		// be merged, the banners give patch something
 		// to use to find its context.
-		b.print("\n#\n# " + a.p.ImportPath + "\n#\n\n")
+		b.Print("\n#\n# " + a.Package.ImportPath + "\n#\n\n")
 	}
 
-	if buildV {
-		b.print(a.p.ImportPath + "\n")
+	if cfg.BuildV {
+		b.Print(a.Package.ImportPath + "\n")
 	}
 
 	// Make build directory.
-	obj := a.objdir
-	if err := b.mkdir(obj); err != nil {
+	obj := a.Objdir
+	if err := b.Mkdir(obj); err != nil {
 		return err
 	}
 
 	// make target directory
-	dir, _ := filepath.Split(a.target)
+	dir, _ := filepath.Split(a.Target)
 	if dir != "" {
-		if err := b.mkdir(dir); err != nil {
+		if err := b.Mkdir(dir); err != nil {
 			return err
 		}
 	}
 
 	var gofiles, cgofiles, objdirCgofiles, cfiles, sfiles, cxxfiles, objects, cgoObjects, pcCFLAGS, pcLDFLAGS []string
 
-	gofiles = append(gofiles, a.p.GoFiles...)
-	cgofiles = append(cgofiles, a.p.CgoFiles...)
-	cfiles = append(cfiles, a.p.CFiles...)
-	sfiles = append(sfiles, a.p.SFiles...)
-	cxxfiles = append(cxxfiles, a.p.CXXFiles...)
+	gofiles = append(gofiles, a.Package.GoFiles...)
+	cgofiles = append(cgofiles, a.Package.CgoFiles...)
+	cfiles = append(cfiles, a.Package.CFiles...)
+	sfiles = append(sfiles, a.Package.SFiles...)
+	cxxfiles = append(cxxfiles, a.Package.CXXFiles...)
 
-	if a.p.usesCgo() || a.p.usesSwig() {
-		if pcCFLAGS, pcLDFLAGS, err = b.getPkgConfigFlags(a.p); err != nil {
+	if a.Package.UsesCgo() || a.Package.UsesSwig() {
+		if pcCFLAGS, pcLDFLAGS, err = b.getPkgConfigFlags(a.Package); err != nil {
 			return
 		}
 	}
@@ -1465,8 +1302,8 @@
 	// Run SWIG on each .swig and .swigcxx file.
 	// Each run will generate two files, a .go file and a .c or .cxx file.
 	// The .go file will use import "C" and is to be processed by cgo.
-	if a.p.usesSwig() {
-		outGo, outC, outCXX, err := b.swig(a.p, obj, pcCFLAGS)
+	if a.Package.UsesSwig() {
+		outGo, outC, outCXX, err := b.swig(a.Package, obj, pcCFLAGS)
 		if err != nil {
 			return err
 		}
@@ -1476,7 +1313,7 @@
 	}
 
 	// Run cgo.
-	if a.p.usesCgo() || a.p.usesSwig() {
+	if a.Package.UsesCgo() || a.Package.UsesSwig() {
 		// In a package using cgo, cgo compiles the C, C++ and assembly files with gcc.
 		// There is one exception: runtime/cgo's job is to bridge the
 		// cgo and non-cgo worlds, so it necessarily has files in both.
@@ -1484,7 +1321,7 @@
 		var gccfiles []string
 		gccfiles = append(gccfiles, cfiles...)
 		cfiles = nil
-		if a.p.Standard && a.p.ImportPath == "runtime/cgo" {
+		if a.Package.Standard && a.Package.ImportPath == "runtime/cgo" {
 			filter := func(files, nongcc, gcc []string) ([]string, []string) {
 				for _, f := range files {
 					if strings.HasPrefix(f, "gcc_") {
@@ -1497,31 +1334,43 @@
 			}
 			sfiles, gccfiles = filter(sfiles, sfiles[:0], gccfiles)
 		} else {
+			for _, sfile := range sfiles {
+				data, err := ioutil.ReadFile(filepath.Join(a.Package.Dir, sfile))
+				if err == nil {
+					if bytes.HasPrefix(data, []byte("TEXT")) || bytes.Contains(data, []byte("\nTEXT")) ||
+						bytes.HasPrefix(data, []byte("DATA")) || bytes.Contains(data, []byte("\nDATA")) ||
+						bytes.HasPrefix(data, []byte("GLOBL")) || bytes.Contains(data, []byte("\nGLOBL")) {
+						return fmt.Errorf("package using cgo has Go assembly file %s", sfile)
+					}
+				}
+			}
 			gccfiles = append(gccfiles, sfiles...)
 			sfiles = nil
 		}
 
-		cgoExe := tool("cgo")
-		if a.cgo != nil && a.cgo.target != "" {
-			cgoExe = a.cgo.target
+		var cgoExe string
+		if a.cgo != nil && a.cgo.Target != "" {
+			cgoExe = a.cgo.Target
+		} else {
+			cgoExe = base.Tool("cgo")
 		}
-		outGo, outObj, err := b.cgo(a, cgoExe, obj, pcCFLAGS, pcLDFLAGS, cgofiles, objdirCgofiles, gccfiles, cxxfiles, a.p.MFiles, a.p.FFiles)
+		outGo, outObj, err := b.cgo(a, cgoExe, obj, pcCFLAGS, pcLDFLAGS, cgofiles, objdirCgofiles, gccfiles, cxxfiles, a.Package.MFiles, a.Package.FFiles)
 		if err != nil {
 			return err
 		}
-		if _, ok := buildToolchain.(gccgoToolchain); ok {
-			cgoObjects = append(cgoObjects, filepath.Join(a.objdir, "_cgo_flags"))
+		if cfg.BuildToolchainName == "gccgo" {
+			cgoObjects = append(cgoObjects, filepath.Join(a.Objdir, "_cgo_flags"))
 		}
 		cgoObjects = append(cgoObjects, outObj...)
 		gofiles = append(gofiles, outGo...)
 	}
 
 	if len(gofiles) == 0 {
-		return &build.NoGoError{Dir: a.p.Dir}
+		return &load.NoGoError{Package: a.Package}
 	}
 
 	// If we're doing coverage, preprocess the .go files and put them in the work directory
-	if a.p.coverMode != "" {
+	if a.Package.Internal.CoverMode != "" {
 		for i, file := range gofiles {
 			var sourceFile string
 			var coverFile string
@@ -1533,12 +1382,12 @@
 				coverFile = filepath.Join(obj, base)
 				key = strings.TrimSuffix(base, ".cgo1.go") + ".go"
 			} else {
-				sourceFile = filepath.Join(a.p.Dir, file)
+				sourceFile = filepath.Join(a.Package.Dir, file)
 				coverFile = filepath.Join(obj, file)
 				key = file
 			}
-			cover := a.p.coverVars[key]
-			if cover == nil || isTestFile(file) {
+			cover := a.Package.Internal.CoverVars[key]
+			if cover == nil || base.IsTestFile(file) {
 				// Not covering this file.
 				continue
 			}
@@ -1553,9 +1402,9 @@
 	inc := b.includeArgs("-I", allArchiveActions(a))
 
 	// Compile Go.
-	ofile, out, err := buildToolchain.gc(b, a.p, a.objpkg, obj, len(sfiles) > 0, inc, gofiles)
+	ofile, out, err := BuildToolchain.gc(b, a.Package, a.Objpkg, obj, len(sfiles) > 0, inc, gofiles)
 	if len(out) > 0 {
-		b.showOutput(a.p.Dir, a.p.ImportPath, b.processOutput(out))
+		b.showOutput(a.Package.Dir, a.Package.ImportPath, b.processOutput(out))
 		if err != nil {
 			return errPrintedOutput
 		}
@@ -1563,32 +1412,32 @@
 	if err != nil {
 		return err
 	}
-	if ofile != a.objpkg {
+	if ofile != a.Objpkg {
 		objects = append(objects, ofile)
 	}
 
 	// Copy .h files named for goos or goarch or goos_goarch
 	// to names using GOOS and GOARCH.
 	// For example, defs_linux_amd64.h becomes defs_GOOS_GOARCH.h.
-	_goos_goarch := "_" + goos + "_" + goarch
-	_goos := "_" + goos
-	_goarch := "_" + goarch
-	for _, file := range a.p.HFiles {
+	_goos_goarch := "_" + cfg.Goos + "_" + cfg.Goarch
+	_goos := "_" + cfg.Goos
+	_goarch := "_" + cfg.Goarch
+	for _, file := range a.Package.HFiles {
 		name, ext := fileExtSplit(file)
 		switch {
 		case strings.HasSuffix(name, _goos_goarch):
 			targ := file[:len(name)-len(_goos_goarch)] + "_GOOS_GOARCH." + ext
-			if err := b.copyFile(a, obj+targ, filepath.Join(a.p.Dir, file), 0666, true); err != nil {
+			if err := b.copyFile(a, obj+targ, filepath.Join(a.Package.Dir, file), 0666, true); err != nil {
 				return err
 			}
 		case strings.HasSuffix(name, _goarch):
 			targ := file[:len(name)-len(_goarch)] + "_GOARCH." + ext
-			if err := b.copyFile(a, obj+targ, filepath.Join(a.p.Dir, file), 0666, true); err != nil {
+			if err := b.copyFile(a, obj+targ, filepath.Join(a.Package.Dir, file), 0666, true); err != nil {
 				return err
 			}
 		case strings.HasSuffix(name, _goos):
 			targ := file[:len(name)-len(_goos)] + "_GOOS." + ext
-			if err := b.copyFile(a, obj+targ, filepath.Join(a.p.Dir, file), 0666, true); err != nil {
+			if err := b.copyFile(a, obj+targ, filepath.Join(a.Package.Dir, file), 0666, true); err != nil {
 				return err
 			}
 		}
@@ -1596,7 +1445,7 @@
 
 	for _, file := range cfiles {
 		out := file[:len(file)-len(".c")] + ".o"
-		if err := buildToolchain.cc(b, a.p, obj, obj+out, file); err != nil {
+		if err := BuildToolchain.cc(b, a.Package, obj, obj+out, file); err != nil {
 			return err
 		}
 		objects = append(objects, out)
@@ -1604,7 +1453,7 @@
 
 	// Assemble .s files.
 	if len(sfiles) > 0 {
-		ofiles, err := buildToolchain.asm(b, a.p, obj, sfiles)
+		ofiles, err := BuildToolchain.asm(b, a.Package, obj, sfiles)
 		if err != nil {
 			return err
 		}
@@ -1618,8 +1467,8 @@
 	objects = append(objects, cgoObjects...)
 
 	// Add system object files.
-	for _, syso := range a.p.SysoFiles {
-		objects = append(objects, filepath.Join(a.p.Dir, syso))
+	for _, syso := range a.Package.SysoFiles {
+		objects = append(objects, filepath.Join(a.Package.Dir, syso))
 	}
 
 	// Pack into archive in obj directory.
@@ -1628,18 +1477,18 @@
 	// If the Go compiler wrote an archive and the package is entirely
 	// Go sources, there is no pack to execute at all.
 	if len(objects) > 0 {
-		if err := buildToolchain.pack(b, a.p, obj, a.objpkg, objects); err != nil {
+		if err := BuildToolchain.pack(b, a.Package, obj, a.Objpkg, objects); err != nil {
 			return err
 		}
 	}
 
 	// Link if needed.
-	if a.link {
+	if a.Link {
 		// The compiler only cares about direct imports, but the
 		// linker needs the whole dependency tree.
-		all := actionList(a)
+		all := ActionList(a)
 		all = all[:len(all)-1] // drop a
-		if err := buildToolchain.ld(b, a, a.target, all, a.objpkg, objects); err != nil {
+		if err := BuildToolchain.ld(b, a, a.Target, all, a.Objpkg, objects); err != nil {
 			return err
 		}
 	}
@@ -1647,10 +1496,10 @@
 	return nil
 }
 
-// pkgconfigCmd returns a pkg-config binary name
+// PkgconfigCmd returns a pkg-config binary name
 // defaultPkgConfig is defined in zdefaultcc.go, written by cmd/dist.
-func (b *builder) pkgconfigCmd() string {
-	return envList("PKG_CONFIG", defaultPkgConfig)[0]
+func (b *Builder) PkgconfigCmd() string {
+	return envList("PKG_CONFIG", cfg.DefaultPkgConfig)[0]
 }
 
 // splitPkgConfigOutput parses the pkg-config output into a slice of
@@ -1687,23 +1536,23 @@
 }
 
 // Calls pkg-config if needed and returns the cflags/ldflags needed to build the package.
-func (b *builder) getPkgConfigFlags(p *Package) (cflags, ldflags []string, err error) {
+func (b *Builder) getPkgConfigFlags(p *load.Package) (cflags, ldflags []string, err error) {
 	if pkgs := p.CgoPkgConfig; len(pkgs) > 0 {
 		var out []byte
-		out, err = b.runOut(p.Dir, p.ImportPath, nil, b.pkgconfigCmd(), "--cflags", pkgs)
+		out, err = b.runOut(p.Dir, p.ImportPath, nil, b.PkgconfigCmd(), "--cflags", pkgs)
 		if err != nil {
-			b.showOutput(p.Dir, b.pkgconfigCmd()+" --cflags "+strings.Join(pkgs, " "), string(out))
-			b.print(err.Error() + "\n")
+			b.showOutput(p.Dir, b.PkgconfigCmd()+" --cflags "+strings.Join(pkgs, " "), string(out))
+			b.Print(err.Error() + "\n")
 			err = errPrintedOutput
 			return
 		}
 		if len(out) > 0 {
 			cflags = splitPkgConfigOutput(out)
 		}
-		out, err = b.runOut(p.Dir, p.ImportPath, nil, b.pkgconfigCmd(), "--libs", pkgs)
+		out, err = b.runOut(p.Dir, p.ImportPath, nil, b.PkgconfigCmd(), "--libs", pkgs)
 		if err != nil {
-			b.showOutput(p.Dir, b.pkgconfigCmd()+" --libs "+strings.Join(pkgs, " "), string(out))
-			b.print(err.Error() + "\n")
+			b.showOutput(p.Dir, b.PkgconfigCmd()+" --libs "+strings.Join(pkgs, " "), string(out))
+			b.Print(err.Error() + "\n")
 			err = errPrintedOutput
 			return
 		}
@@ -1714,35 +1563,35 @@
 	return
 }
 
-func (b *builder) installShlibname(a *action) error {
-	a1 := a.deps[0]
-	err := ioutil.WriteFile(a.target, []byte(filepath.Base(a1.target)+"\n"), 0666)
+func (b *Builder) installShlibname(a *Action) error {
+	a1 := a.Deps[0]
+	err := ioutil.WriteFile(a.Target, []byte(filepath.Base(a1.Target)+"\n"), 0666)
 	if err != nil {
 		return err
 	}
-	if buildX {
-		b.showcmd("", "echo '%s' > %s # internal", filepath.Base(a1.target), a.target)
+	if cfg.BuildX {
+		b.Showcmd("", "echo '%s' > %s # internal", filepath.Base(a1.Target), a.Target)
 	}
 	return nil
 }
 
-func (b *builder) linkShared(a *action) (err error) {
-	allactions := actionList(a)
+func (b *Builder) linkShared(a *Action) (err error) {
+	allactions := ActionList(a)
 	allactions = allactions[:len(allactions)-1]
-	return buildToolchain.ldShared(b, a.deps, a.target, allactions)
+	return BuildToolchain.ldShared(b, a.Deps, a.Target, allactions)
 }
 
-// install is the action for installing a single package or executable.
-func (b *builder) install(a *action) (err error) {
+// BuildInstallFunc is the action for installing a single package or executable.
+func BuildInstallFunc(b *Builder, a *Action) (err error) {
 	defer func() {
 		if err != nil && err != errPrintedOutput {
-			err = fmt.Errorf("go install %s: %v", a.p.ImportPath, err)
+			err = fmt.Errorf("go install %s: %v", a.Package.ImportPath, err)
 		}
 	}()
-	a1 := a.deps[0]
+	a1 := a.Deps[0]
 	perm := os.FileMode(0666)
-	if a1.link {
-		switch buildBuildmode {
+	if a1.Link {
+		switch cfg.BuildBuildmode {
 		case "c-archive", "c-shared", "plugin":
 		default:
 			perm = 0777
@@ -1750,9 +1599,9 @@
 	}
 
 	// make target directory
-	dir, _ := filepath.Split(a.target)
+	dir, _ := filepath.Split(a.Target)
 	if dir != "" {
-		if err := b.mkdir(dir); err != nil {
+		if err := b.Mkdir(dir); err != nil {
 			return err
 		}
 	}
@@ -1761,32 +1610,32 @@
 	// garbage down in a large build. On an operating system
 	// with aggressive buffering, cleaning incrementally like
 	// this keeps the intermediate objects from hitting the disk.
-	if !buildWork {
-		defer os.RemoveAll(a1.objdir)
-		defer os.Remove(a1.target)
+	if !cfg.BuildWork {
+		defer os.RemoveAll(a1.Objdir)
+		defer os.Remove(a1.Target)
 	}
 
-	return b.moveOrCopyFile(a, a.target, a1.target, perm, false)
+	return b.moveOrCopyFile(a, a.Target, a1.Target, perm, false)
 }
 
 // includeArgs returns the -I or -L directory list for access
 // to the results of the list of actions.
-func (b *builder) includeArgs(flag string, all []*action) []string {
+func (b *Builder) includeArgs(flag string, all []*Action) []string {
 	inc := []string{}
 	incMap := map[string]bool{
-		b.work:    true, // handled later
-		gorootPkg: true,
-		"":        true, // ignore empty strings
+		b.WorkDir:     true, // handled later
+		cfg.GOROOTpkg: true,
+		"":            true, // ignore empty strings
 	}
 
 	// Look in the temporary space for results of test-specific actions.
 	// This is the $WORK/my/package/_test directory for the
 	// package being built, so there are few of these.
 	for _, a1 := range all {
-		if a1.p == nil {
+		if a1.Package == nil {
 			continue
 		}
-		if dir := a1.pkgdir; dir != a1.p.build.PkgRoot && !incMap[dir] {
+		if dir := a1.Pkgdir; dir != a1.Package.Internal.Build.PkgRoot && !incMap[dir] {
 			incMap[dir] = true
 			inc = append(inc, flag, dir)
 		}
@@ -1794,18 +1643,18 @@
 
 	// Also look in $WORK for any non-test packages that have
 	// been built but not installed.
-	inc = append(inc, flag, b.work)
+	inc = append(inc, flag, b.WorkDir)
 
 	// Finally, look in the installed package directories for each action.
 	// First add the package dirs corresponding to GOPATH entries
 	// in the original GOPATH order.
 	need := map[string]*build.Package{}
 	for _, a1 := range all {
-		if a1.p != nil && a1.pkgdir == a1.p.build.PkgRoot {
-			need[a1.p.build.Root] = a1.p.build
+		if a1.Package != nil && a1.Pkgdir == a1.Package.Internal.Build.PkgRoot {
+			need[a1.Package.Internal.Build.Root] = a1.Package.Internal.Build
 		}
 	}
-	for _, root := range gopath {
+	for _, root := range cfg.Gopath {
 		if p := need[root]; p != nil && !incMap[p.PkgRoot] {
 			incMap[p.PkgRoot] = true
 			inc = append(inc, flag, p.PkgTargetRoot)
@@ -1814,12 +1663,12 @@
 
 	// Then add anything that's left.
 	for _, a1 := range all {
-		if a1.p == nil {
+		if a1.Package == nil {
 			continue
 		}
-		if dir := a1.pkgdir; dir == a1.p.build.PkgRoot && !incMap[dir] {
+		if dir := a1.Pkgdir; dir == a1.Package.Internal.Build.PkgRoot && !incMap[dir] {
 			incMap[dir] = true
-			inc = append(inc, flag, a1.p.build.PkgTargetRoot)
+			inc = append(inc, flag, a1.Package.Internal.Build.PkgTargetRoot)
 		}
 	}
 
@@ -1827,15 +1676,24 @@
 }
 
 // moveOrCopyFile is like 'mv src dst' or 'cp src dst'.
-func (b *builder) moveOrCopyFile(a *action, dst, src string, perm os.FileMode, force bool) error {
-	if buildN {
-		b.showcmd("", "mv %s %s", src, dst)
+func (b *Builder) moveOrCopyFile(a *Action, dst, src string, perm os.FileMode, force bool) error {
+	if cfg.BuildN {
+		b.Showcmd("", "mv %s %s", src, dst)
 		return nil
 	}
 
 	// If we can update the mode and rename to the dst, do it.
 	// Otherwise fall back to standard copy.
 
+	// If the destination directory has the group sticky bit set,
+	// we have to copy the file to retain the correct permissions.
+	// https://golang.org/issue/18878
+	if fi, err := os.Stat(filepath.Dir(dst)); err == nil {
+		if fi.IsDir() && (fi.Mode()&os.ModeSetgid) != 0 {
+			return b.copyFile(a, dst, src, perm, force)
+		}
+	}
+
 	// The perm argument is meant to be adjusted according to umask,
 	// but we don't know what the umask is.
 	// Create a dummy file to find out.
@@ -1855,8 +1713,8 @@
 
 	if err := os.Chmod(src, mode); err == nil {
 		if err := os.Rename(src, dst); err == nil {
-			if buildX {
-				b.showcmd("", "mv %s %s", src, dst)
+			if cfg.BuildX {
+				b.Showcmd("", "mv %s %s", src, dst)
 			}
 			return nil
 		}
@@ -1866,10 +1724,10 @@
 }
 
 // copyFile is like 'cp src dst'.
-func (b *builder) copyFile(a *action, dst, src string, perm os.FileMode, force bool) error {
-	if buildN || buildX {
-		b.showcmd("", "cp %s %s", src, dst)
-		if buildN {
+func (b *Builder) copyFile(a *Action, dst, src string, perm os.FileMode, force bool) error {
+	if cfg.BuildN || cfg.BuildX {
+		b.Showcmd("", "cp %s %s", src, dst)
+		if cfg.BuildN {
 			return nil
 		}
 	}
@@ -1893,7 +1751,7 @@
 	}
 
 	// On Windows, remove lingering ~ file from last attempt.
-	if toolIsWindows {
+	if base.ToolIsWindows {
 		if _, err := os.Stat(dst + "~"); err == nil {
 			os.Remove(dst + "~")
 		}
@@ -1901,7 +1759,7 @@
 
 	mayberemovefile(dst)
 	df, err := os.OpenFile(dst, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
-	if err != nil && toolIsWindows {
+	if err != nil && base.ToolIsWindows {
 		// Windows does not allow deletion of a binary file
 		// while it is executing. Try to move it out of the way.
 		// If the move fails, which is likely, we'll try again the
@@ -1925,31 +1783,31 @@
 }
 
 // Install the cgo export header file, if there is one.
-func (b *builder) installHeader(a *action) error {
-	src := a.objdir + "_cgo_install.h"
+func (b *Builder) installHeader(a *Action) error {
+	src := a.Objdir + "_cgo_install.h"
 	if _, err := os.Stat(src); os.IsNotExist(err) {
 		// If the file does not exist, there are no exported
 		// functions, and we do not install anything.
 		return nil
 	}
 
-	dir, _ := filepath.Split(a.target)
+	dir, _ := filepath.Split(a.Target)
 	if dir != "" {
-		if err := b.mkdir(dir); err != nil {
+		if err := b.Mkdir(dir); err != nil {
 			return err
 		}
 	}
 
-	return b.moveOrCopyFile(a, a.target, src, 0666, true)
+	return b.moveOrCopyFile(a, a.Target, src, 0666, true)
 }
 
 // cover runs, in effect,
 //	go tool cover -mode=b.coverMode -var="varName" -o dst.go src.go
-func (b *builder) cover(a *action, dst, src string, perm os.FileMode, varName string) error {
-	return b.run(a.objdir, "cover "+a.p.ImportPath, nil,
-		buildToolExec,
-		tool("cover"),
-		"-mode", a.p.coverMode,
+func (b *Builder) cover(a *Action, dst, src string, perm os.FileMode, varName string) error {
+	return b.run(a.Objdir, "cover "+a.Package.ImportPath, nil,
+		cfg.BuildToolexec,
+		base.Tool("cover"),
+		"-mode", a.Package.Internal.CoverMode,
 		"-var", varName,
 		"-o", dst,
 		src)
@@ -1999,14 +1857,14 @@
 //	If dir is non-empty and the script is not in dir right now,
 //	fmtcmd inserts "cd dir\n" before the command.
 //
-//	fmtcmd replaces the value of b.work with $WORK.
+//	fmtcmd replaces the value of b.WorkDir with $WORK.
 //	fmtcmd replaces the value of goroot with $GOROOT.
 //	fmtcmd replaces the value of b.gobin with $GOBIN.
 //
 //	fmtcmd replaces the name of the current directory with dot (.)
 //	but only when it is at the beginning of a space-separated token.
 //
-func (b *builder) fmtcmd(dir string, format string, args ...interface{}) string {
+func (b *Builder) fmtcmd(dir string, format string, args ...interface{}) string {
 	cmd := fmt.Sprintf(format, args...)
 	if dir != "" && dir != "/" {
 		cmd = strings.Replace(" "+cmd, " "+dir, " .", -1)[1:]
@@ -2015,18 +1873,18 @@
 			cmd = "cd " + dir + "\n" + cmd
 		}
 	}
-	if b.work != "" {
-		cmd = strings.Replace(cmd, b.work, "$WORK", -1)
+	if b.WorkDir != "" {
+		cmd = strings.Replace(cmd, b.WorkDir, "$WORK", -1)
 	}
 	return cmd
 }
 
 // showcmd prints the given command to standard output
 // for the implementation of -n or -x.
-func (b *builder) showcmd(dir string, format string, args ...interface{}) {
+func (b *Builder) Showcmd(dir string, format string, args ...interface{}) {
 	b.output.Lock()
 	defer b.output.Unlock()
-	b.print(b.fmtcmd(dir, format, args...) + "\n")
+	b.Print(b.fmtcmd(dir, format, args...) + "\n")
 }
 
 // showOutput prints "# desc" followed by the given output.
@@ -2051,41 +1909,18 @@
 //
 // showOutput also replaces references to the work directory with $WORK.
 //
-func (b *builder) showOutput(dir, desc, out string) {
+func (b *Builder) showOutput(dir, desc, out string) {
 	prefix := "# " + desc
 	suffix := "\n" + out
-	if reldir := shortPath(dir); reldir != dir {
+	if reldir := base.ShortPath(dir); reldir != dir {
 		suffix = strings.Replace(suffix, " "+dir, " "+reldir, -1)
 		suffix = strings.Replace(suffix, "\n"+dir, "\n"+reldir, -1)
 	}
-	suffix = strings.Replace(suffix, " "+b.work, " $WORK", -1)
+	suffix = strings.Replace(suffix, " "+b.WorkDir, " $WORK", -1)
 
 	b.output.Lock()
 	defer b.output.Unlock()
-	b.print(prefix, suffix)
-}
-
-// shortPath returns an absolute or relative name for path, whatever is shorter.
-func shortPath(path string) string {
-	if rel, err := filepath.Rel(cwd, path); err == nil && len(rel) < len(path) {
-		return rel
-	}
-	return path
-}
-
-// relPaths returns a copy of paths with absolute paths
-// made relative to the current directory if they would be shorter.
-func relPaths(paths []string) []string {
-	var out []string
-	pwd, _ := os.Getwd()
-	for _, p := range paths {
-		rel, err := filepath.Rel(pwd, p)
-		if err == nil && len(rel) < len(p) {
-			p = rel
-		}
-		out = append(out, p)
-	}
-	return out
+	b.Print(prefix, suffix)
 }
 
 // errPrintedOutput is a special error indicating that a command failed
@@ -2095,17 +1930,17 @@
 // print this error.
 var errPrintedOutput = errors.New("already printed output - no need to show error")
 
-var cgoLine = regexp.MustCompile(`\[[^\[\]]+\.cgo1\.go:[0-9]+\]`)
+var cgoLine = regexp.MustCompile(`\[[^\[\]]+\.cgo1\.go:[0-9]+(:[0-9]+)?\]`)
 var cgoTypeSigRe = regexp.MustCompile(`\b_Ctype_\B`)
 
 // run runs the command given by cmdline in the directory dir.
 // If the command fails, run prints information about the failure
 // and returns a non-nil error.
-func (b *builder) run(dir string, desc string, env []string, cmdargs ...interface{}) error {
+func (b *Builder) run(dir string, desc string, env []string, cmdargs ...interface{}) error {
 	out, err := b.runOut(dir, desc, env, cmdargs...)
 	if len(out) > 0 {
 		if desc == "" {
-			desc = b.fmtcmd(dir, "%s", strings.Join(stringList(cmdargs...), " "))
+			desc = b.fmtcmd(dir, "%s", strings.Join(str.StringList(cmdargs...), " "))
 		}
 		b.showOutput(dir, desc, b.processOutput(out))
 		if err != nil {
@@ -2116,7 +1951,7 @@
 }
 
 // processOutput prepares the output of runOut to be output to the console.
-func (b *builder) processOutput(out []byte) string {
+func (b *Builder) processOutput(out []byte) string {
 	if out[len(out)-1] != '\n' {
 		out = append(out, '\n')
 	}
@@ -2125,7 +1960,7 @@
 	// Replace x.go:19[/tmp/.../x.cgo1.go:18] with x.go:19.
 	// Replace *[100]_Ctype_foo with *[100]C.foo.
 	// If we're using -x, assume we're debugging and want the full dump, so disable the rewrite.
-	if !buildX && cgoLine.MatchString(messages) {
+	if !cfg.BuildX && cgoLine.MatchString(messages) {
 		messages = cgoLine.ReplaceAllString(messages, "")
 		messages = cgoTypeSigRe.ReplaceAllString(messages, "C.")
 	}
@@ -2134,17 +1969,17 @@
 
 // runOut runs the command given by cmdline in the directory dir.
 // It returns the command output and any errors that occurred.
-func (b *builder) runOut(dir string, desc string, env []string, cmdargs ...interface{}) ([]byte, error) {
-	cmdline := stringList(cmdargs...)
-	if buildN || buildX {
+func (b *Builder) runOut(dir string, desc string, env []string, cmdargs ...interface{}) ([]byte, error) {
+	cmdline := str.StringList(cmdargs...)
+	if cfg.BuildN || cfg.BuildX {
 		var envcmdline string
 		for i := range env {
 			envcmdline += env[i]
 			envcmdline += " "
 		}
 		envcmdline += joinUnambiguously(cmdline)
-		b.showcmd(dir, "%s", envcmdline)
-		if buildN {
+		b.Showcmd(dir, "%s", envcmdline)
+		if cfg.BuildN {
 			return nil, nil
 		}
 	}
@@ -2156,7 +1991,7 @@
 		cmd.Stdout = &buf
 		cmd.Stderr = &buf
 		cmd.Dir = dir
-		cmd.Env = mergeEnvLists(env, envForDir(cmd.Dir, os.Environ()))
+		cmd.Env = base.MergeEnvLists(env, base.EnvForDir(cmd.Dir, os.Environ()))
 		err := cmd.Run()
 
 		// cmd.Run will fail on Unix if some other process has the binary
@@ -2177,7 +2012,7 @@
 		// until the time of the explicit close, and the race would remain.
 		//
 		// On Unix systems, this results in ETXTBSY, which formats
-		// as "text file busy".  Rather than hard-code specific error cases,
+		// as "text file busy". Rather than hard-code specific error cases,
 		// we just look for that string. If this happens, sleep a little
 		// and try again. We let this happen three times, with increasing
 		// sleep lengths: 100+200+400 ms = 0.7 seconds.
@@ -2238,7 +2073,7 @@
 }
 
 // mkdir makes the named directory.
-func (b *builder) mkdir(dir string) error {
+func (b *Builder) Mkdir(dir string) error {
 	b.exec.Lock()
 	defer b.exec.Unlock()
 	// We can be a little aggressive about being
@@ -2248,9 +2083,9 @@
 	}
 	b.mkdirCache[dir] = true
 
-	if buildN || buildX {
-		b.showcmd("", "mkdir -p %s", dir)
-		if buildN {
+	if cfg.BuildN || cfg.BuildX {
+		b.Showcmd("", "mkdir -p %s", dir)
+		if cfg.BuildN {
 			return nil
 		}
 	}
@@ -2280,23 +2115,23 @@
 type toolchain interface {
 	// gc runs the compiler in a specific directory on a set of files
 	// and returns the name of the generated output file.
-	gc(b *builder, p *Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, out []byte, err error)
+	gc(b *Builder, p *load.Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, out []byte, err error)
 	// cc runs the toolchain's C compiler in a directory on a C file
 	// to produce an output file.
-	cc(b *builder, p *Package, objdir, ofile, cfile string) error
+	cc(b *Builder, p *load.Package, objdir, ofile, cfile string) error
 	// asm runs the assembler in a specific directory on specific files
 	// and returns a list of named output files.
-	asm(b *builder, p *Package, obj string, sfiles []string) ([]string, error)
+	asm(b *Builder, p *load.Package, obj string, sfiles []string) ([]string, error)
 	// pkgpath builds an appropriate path for a temporary package file.
-	pkgpath(basedir string, p *Package) string
+	Pkgpath(basedir string, p *load.Package) string
 	// pack runs the archive packer in a specific directory to create
 	// an archive from a set of object files.
 	// typically it is run in the object directory.
-	pack(b *builder, p *Package, objDir, afile string, ofiles []string) error
+	pack(b *Builder, p *load.Package, objDir, afile string, ofiles []string) error
 	// ld runs the linker to create an executable starting at mainpkg.
-	ld(b *builder, root *action, out string, allactions []*action, mainpkg string, ofiles []string) error
+	ld(b *Builder, root *Action, out string, allactions []*Action, mainpkg string, ofiles []string) error
 	// ldShared runs the linker to create a shared library containing the pkgs built by toplevelactions
-	ldShared(b *builder, toplevelactions []*action, out string, allactions []*action) error
+	ldShared(b *Builder, toplevelactions []*Action, out string, allactions []*Action) error
 
 	compiler() string
 	linker() string
@@ -2305,7 +2140,7 @@
 type noToolchain struct{}
 
 func noCompiler() error {
-	log.Fatalf("unknown compiler %q", buildContext.Compiler)
+	log.Fatalf("unknown compiler %q", cfg.BuildContext.Compiler)
 	return nil
 }
 
@@ -2319,32 +2154,32 @@
 	return ""
 }
 
-func (noToolchain) gc(b *builder, p *Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, out []byte, err error) {
+func (noToolchain) gc(b *Builder, p *load.Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, out []byte, err error) {
 	return "", nil, noCompiler()
 }
 
-func (noToolchain) asm(b *builder, p *Package, obj string, sfiles []string) ([]string, error) {
+func (noToolchain) asm(b *Builder, p *load.Package, obj string, sfiles []string) ([]string, error) {
 	return nil, noCompiler()
 }
 
-func (noToolchain) pkgpath(basedir string, p *Package) string {
+func (noToolchain) Pkgpath(basedir string, p *load.Package) string {
 	noCompiler()
 	return ""
 }
 
-func (noToolchain) pack(b *builder, p *Package, objDir, afile string, ofiles []string) error {
+func (noToolchain) pack(b *Builder, p *load.Package, objDir, afile string, ofiles []string) error {
 	return noCompiler()
 }
 
-func (noToolchain) ld(b *builder, root *action, out string, allactions []*action, mainpkg string, ofiles []string) error {
+func (noToolchain) ld(b *Builder, root *Action, out string, allactions []*Action, mainpkg string, ofiles []string) error {
 	return noCompiler()
 }
 
-func (noToolchain) ldShared(b *builder, toplevelactions []*action, out string, allactions []*action) error {
+func (noToolchain) ldShared(b *Builder, toplevelactions []*Action, out string, allactions []*Action) error {
 	return noCompiler()
 }
 
-func (noToolchain) cc(b *builder, p *Package, objdir, ofile, cfile string) error {
+func (noToolchain) cc(b *Builder, p *load.Package, objdir, ofile, cfile string) error {
 	return noCompiler()
 }
 
@@ -2352,14 +2187,14 @@
 type gcToolchain struct{}
 
 func (gcToolchain) compiler() string {
-	return tool("compile")
+	return base.Tool("compile")
 }
 
 func (gcToolchain) linker() string {
-	return tool("link")
+	return base.Tool("link")
 }
 
-func (gcToolchain) gc(b *builder, p *Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, output []byte, err error) {
+func (gcToolchain) gc(b *Builder, p *load.Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, output []byte, err error) {
 	if archive != "" {
 		ofile = archive
 	} else {
@@ -2371,7 +2206,11 @@
 	if p.Name == "main" {
 		gcargs[1] = "main"
 	}
-	if p.Standard && (p.ImportPath == "runtime" || strings.HasPrefix(p.ImportPath, "runtime/internal")) {
+	if p.Standard {
+		gcargs = append(gcargs, "-std")
+	}
+	compilingRuntime := p.Standard && (p.ImportPath == "runtime" || strings.HasPrefix(p.ImportPath, "runtime/internal"))
+	if compilingRuntime {
 		// runtime compiles with a special gc flag to emit
 		// additional reflect type data.
 		gcargs = append(gcargs, "-+")
@@ -2384,18 +2223,22 @@
 	extFiles := len(p.CgoFiles) + len(p.CFiles) + len(p.CXXFiles) + len(p.MFiles) + len(p.FFiles) + len(p.SFiles) + len(p.SysoFiles) + len(p.SwigFiles) + len(p.SwigCXXFiles)
 	if p.Standard {
 		switch p.ImportPath {
-		case "bytes", "net", "os", "runtime/pprof", "sync", "time":
+		case "bytes", "internal/poll", "net", "os", "runtime/pprof", "sync", "syscall", "time":
 			extFiles++
 		}
 	}
 	if extFiles == 0 {
 		gcargs = append(gcargs, "-complete")
 	}
-	if buildContext.InstallSuffix != "" {
-		gcargs = append(gcargs, "-installsuffix", buildContext.InstallSuffix)
+	if cfg.BuildContext.InstallSuffix != "" {
+		gcargs = append(gcargs, "-installsuffix", cfg.BuildContext.InstallSuffix)
 	}
-	if p.buildID != "" {
-		gcargs = append(gcargs, "-buildid", p.buildID)
+	if p.Internal.BuildID != "" {
+		gcargs = append(gcargs, "-buildid", p.Internal.BuildID)
+	}
+	platform := cfg.Goos + "/" + cfg.Goarch
+	if p.Internal.OmitDebug || platform == "nacl/amd64p32" || platform == "darwin/arm" || platform == "darwin/arm64" || cfg.Goos == "plan9" {
+		gcargs = append(gcargs, "-dwarf=false")
 	}
 
 	for _, path := range p.Imports {
@@ -2406,13 +2249,34 @@
 		}
 	}
 
-	args := []interface{}{buildToolExec, tool("compile"), "-o", ofile, "-trimpath", b.work, buildGcflags, gcargs, "-D", p.localPrefix, importArgs}
+	gcflags := buildGcflags
+	if compilingRuntime {
+		// Remove -N, if present.
+		// It is not possible to build the runtime with no optimizations,
+		// because the compiler cannot eliminate enough write barriers.
+		gcflags = make([]string, len(buildGcflags))
+		copy(gcflags, buildGcflags)
+		for i := 0; i < len(gcflags); i++ {
+			if gcflags[i] == "-N" {
+				copy(gcflags[i:], gcflags[i+1:])
+				gcflags = gcflags[:len(gcflags)-1]
+				i--
+			}
+		}
+	}
+	args := []interface{}{cfg.BuildToolexec, base.Tool("compile"), "-o", ofile, "-trimpath", b.WorkDir, gcflags, gcargs, "-D", p.Internal.LocalPrefix, importArgs}
 	if ofile == archive {
 		args = append(args, "-pack")
 	}
 	if asmhdr {
 		args = append(args, "-asmhdr", obj+"go_asm.h")
 	}
+
+	// Add -c=N to use concurrent backend compilation, if possible.
+	if c := gcBackendConcurrency(gcflags); c > 1 {
+		args = append(args, fmt.Sprintf("-c=%d", c))
+	}
+
 	for _, f := range gofiles {
 		args = append(args, mkAbs(p.Dir, f))
 	}
@@ -2421,11 +2285,82 @@
 	return ofile, output, err
 }
 
-func (gcToolchain) asm(b *builder, p *Package, obj string, sfiles []string) ([]string, error) {
+// gcBackendConcurrency returns the backend compiler concurrency level for a package compilation.
+func gcBackendConcurrency(gcflags []string) int {
+	// First, check whether we can use -c at all for this compilation.
+	canDashC := concurrentGCBackendCompilationEnabledByDefault
+
+	switch e := os.Getenv("GO19CONCURRENTCOMPILATION"); e {
+	case "0":
+		canDashC = false
+	case "1":
+		canDashC = true
+	case "":
+		// Not set. Use default.
+	default:
+		log.Fatalf("GO19CONCURRENTCOMPILATION must be 0, 1, or unset, got %q", e)
+	}
+
+	if os.Getenv("GOEXPERIMENT") != "" {
+		// Concurrent compilation is presumed incompatible with GOEXPERIMENTs.
+		canDashC = false
+	}
+
+CheckFlags:
+	for _, flag := range gcflags {
+		// Concurrent compilation is presumed incompatible with any gcflags,
+		// except for a small whitelist of commonly used flags.
+		// If the user knows better, they can manually add their own -c to the gcflags.
+		switch flag {
+		case "-N", "-l", "-S", "-B", "-C", "-I":
+			// OK
+		default:
+			canDashC = false
+			break CheckFlags
+		}
+	}
+
+	if !canDashC {
+		return 1
+	}
+
+	// Decide how many concurrent backend compilations to allow.
+	//
+	// If we allow too many, in theory we might end up with p concurrent processes,
+	// each with c concurrent backend compiles, all fighting over the same resources.
+	// However, in practice, that seems not to happen too much.
+	// Most build graphs are surprisingly serial, so p==1 for much of the build.
+	// Furthermore, concurrent backend compilation is only enabled for a part
+	// of the overall compiler execution, so c==1 for much of the build.
+	// So don't worry too much about that interaction for now.
+	//
+	// However, in practice, setting c above 4 tends not to help very much.
+	// See the analysis in CL 41192.
+	//
+	// TODO(josharian): attempt to detect whether this particular compilation
+	// is likely to be a bottleneck, e.g. when:
+	//   - it has no successor packages to compile (usually package main)
+	//   - all paths through the build graph pass through it
+	//   - critical path scheduling says it is high priority
+	// and in such a case, set c to runtime.NumCPU.
+	// We do this now when p==1.
+	if cfg.BuildP == 1 {
+		// No process parallelism. Max out c.
+		return runtime.NumCPU()
+	}
+	// Some process parallelism. Set c to min(4, numcpu).
+	c := 4
+	if ncpu := runtime.NumCPU(); ncpu < c {
+		c = ncpu
+	}
+	return c
+}
+
+func (gcToolchain) asm(b *Builder, p *load.Package, obj string, sfiles []string) ([]string, error) {
 	// Add -I pkg/GOOS_GOARCH so #include "textflag.h" works in .s files.
-	inc := filepath.Join(goroot, "pkg", "include")
-	args := []interface{}{buildToolExec, tool("asm"), "-trimpath", b.work, "-I", obj, "-I", inc, "-D", "GOOS_" + goos, "-D", "GOARCH_" + goarch, buildAsmflags}
-	if p.ImportPath == "runtime" && goarch == "386" {
+	inc := filepath.Join(cfg.GOROOT, "pkg", "include")
+	args := []interface{}{cfg.BuildToolexec, base.Tool("asm"), "-trimpath", b.WorkDir, "-I", obj, "-I", inc, "-D", "GOOS_" + cfg.Goos, "-D", "GOARCH_" + cfg.Goarch, buildAsmflags}
+	if p.ImportPath == "runtime" && cfg.Goarch == "386" {
 		for _, arg := range buildAsmflags {
 			if arg == "-dynlink" {
 				args = append(args, "-D=GOBUILDMODE_shared=1")
@@ -2447,10 +2382,10 @@
 // toolVerify checks that the command line args writes the same output file
 // if run using newTool instead.
 // Unused now but kept around for future use.
-func toolVerify(b *builder, p *Package, newTool string, ofile string, args []interface{}) error {
+func toolVerify(b *Builder, p *load.Package, newTool string, ofile string, args []interface{}) error {
 	newArgs := make([]interface{}, len(args))
 	copy(newArgs, args)
-	newArgs[1] = tool(newTool)
+	newArgs[1] = base.Tool(newTool)
 	newArgs[3] = ofile + ".new" // x.6 becomes x.6.new
 	if err := b.run(p.Dir, p.ImportPath, nil, newArgs...); err != nil {
 		return err
@@ -2464,18 +2399,18 @@
 		return err
 	}
 	if !bytes.Equal(data1, data2) {
-		return fmt.Errorf("%s and %s produced different output files:\n%s\n%s", filepath.Base(args[1].(string)), newTool, strings.Join(stringList(args...), " "), strings.Join(stringList(newArgs...), " "))
+		return fmt.Errorf("%s and %s produced different output files:\n%s\n%s", filepath.Base(args[1].(string)), newTool, strings.Join(str.StringList(args...), " "), strings.Join(str.StringList(newArgs...), " "))
 	}
 	os.Remove(ofile + ".new")
 	return nil
 }
 
-func (gcToolchain) pkgpath(basedir string, p *Package) string {
+func (gcToolchain) Pkgpath(basedir string, p *load.Package) string {
 	end := filepath.FromSlash(p.ImportPath + ".a")
 	return filepath.Join(basedir, end)
 }
 
-func (gcToolchain) pack(b *builder, p *Package, objDir, afile string, ofiles []string) error {
+func (gcToolchain) pack(b *Builder, p *load.Package, objDir, afile string, ofiles []string) error {
 	var absOfiles []string
 	for _, f := range ofiles {
 		absOfiles = append(absOfiles, mkAbs(objDir, f))
@@ -2484,17 +2419,17 @@
 
 	// The archive file should have been created by the compiler.
 	// Since it used to not work that way, verify.
-	if !buildN {
+	if !cfg.BuildN {
 		if _, err := os.Stat(absAfile); err != nil {
-			fatalf("os.Stat of archive file failed: %v", err)
+			base.Fatalf("os.Stat of archive file failed: %v", err)
 		}
 	}
 
-	if buildN || buildX {
-		cmdline := stringList("pack", "r", absAfile, absOfiles)
-		b.showcmd(p.Dir, "%s # internal", joinUnambiguously(cmdline))
+	if cfg.BuildN || cfg.BuildX {
+		cmdline := str.StringList("pack", "r", absAfile, absOfiles)
+		b.Showcmd(p.Dir, "%s # internal", joinUnambiguously(cmdline))
 	}
-	if buildN {
+	if cfg.BuildN {
 		return nil
 	}
 	if err := packInternal(b, absAfile, absOfiles); err != nil {
@@ -2504,7 +2439,7 @@
 	return nil
 }
 
-func packInternal(b *builder, afile string, ofiles []string) error {
+func packInternal(b *Builder, afile string, ofiles []string) error {
 	dst, err := os.OpenFile(afile, os.O_WRONLY|os.O_APPEND, 0)
 	if err != nil {
 		return err
@@ -2584,25 +2519,25 @@
 	return ldflags
 }
 
-func (gcToolchain) ld(b *builder, root *action, out string, allactions []*action, mainpkg string, ofiles []string) error {
+func (gcToolchain) ld(b *Builder, root *Action, out string, allactions []*Action, mainpkg string, ofiles []string) error {
 	importArgs := b.includeArgs("-L", allactions)
-	cxx := len(root.p.CXXFiles) > 0 || len(root.p.SwigCXXFiles) > 0
+	cxx := len(root.Package.CXXFiles) > 0 || len(root.Package.SwigCXXFiles) > 0
 	for _, a := range allactions {
-		if a.p != nil && (len(a.p.CXXFiles) > 0 || len(a.p.SwigCXXFiles) > 0) {
+		if a.Package != nil && (len(a.Package.CXXFiles) > 0 || len(a.Package.SwigCXXFiles) > 0) {
 			cxx = true
 		}
 	}
 	var ldflags []string
-	if buildContext.InstallSuffix != "" {
-		ldflags = append(ldflags, "-installsuffix", buildContext.InstallSuffix)
+	if cfg.BuildContext.InstallSuffix != "" {
+		ldflags = append(ldflags, "-installsuffix", cfg.BuildContext.InstallSuffix)
 	}
-	if root.p.omitDWARF {
-		ldflags = append(ldflags, "-w")
+	if root.Package.Internal.OmitDebug {
+		ldflags = append(ldflags, "-s", "-w")
 	}
-	if buildBuildmode == "plugin" {
-		pluginpath := root.p.ImportPath
+	if cfg.BuildBuildmode == "plugin" {
+		pluginpath := root.Package.ImportPath
 		if pluginpath == "command-line-arguments" {
-			pluginpath = "plugin/unnamed-" + root.p.buildID
+			pluginpath = "plugin/unnamed-" + root.Package.Internal.BuildID
 		}
 		ldflags = append(ldflags, "-pluginpath", pluginpath)
 	}
@@ -2613,16 +2548,16 @@
 	// Else, use the CC environment variable and defaultCC as fallback.
 	var compiler []string
 	if cxx {
-		compiler = envList("CXX", defaultCXX)
+		compiler = envList("CXX", cfg.DefaultCXX)
 	} else {
-		compiler = envList("CC", defaultCC)
+		compiler = envList("CC", cfg.DefaultCC)
 	}
 	ldflags = setextld(ldflags, compiler)
 	ldflags = append(ldflags, "-buildmode="+ldBuildmode)
-	if root.p.buildID != "" {
-		ldflags = append(ldflags, "-buildid="+root.p.buildID)
+	if root.Package.Internal.BuildID != "" {
+		ldflags = append(ldflags, "-buildid="+root.Package.Internal.BuildID)
 	}
-	ldflags = append(ldflags, buildLdflags...)
+	ldflags = append(ldflags, cfg.BuildLdflags...)
 
 	// On OS X when using external linking to build a shared library,
 	// the argument passed here to -o ends up recorded in the final
@@ -2632,21 +2567,21 @@
 	// run the link in the output directory so that -o can name
 	// just the final path element.
 	dir := "."
-	if goos == "darwin" && buildBuildmode == "c-shared" {
+	if cfg.Goos == "darwin" && cfg.BuildBuildmode == "c-shared" {
 		dir, out = filepath.Split(out)
 	}
 
-	return b.run(dir, root.p.ImportPath, nil, buildToolExec, tool("link"), "-o", out, importArgs, ldflags, mainpkg)
+	return b.run(dir, root.Package.ImportPath, nil, cfg.BuildToolexec, base.Tool("link"), "-o", out, importArgs, ldflags, mainpkg)
 }
 
-func (gcToolchain) ldShared(b *builder, toplevelactions []*action, out string, allactions []*action) error {
+func (gcToolchain) ldShared(b *Builder, toplevelactions []*Action, out string, allactions []*Action) error {
 	importArgs := b.includeArgs("-L", allactions)
-	ldflags := []string{"-installsuffix", buildContext.InstallSuffix}
+	ldflags := []string{"-installsuffix", cfg.BuildContext.InstallSuffix}
 	ldflags = append(ldflags, "-buildmode=shared")
-	ldflags = append(ldflags, buildLdflags...)
+	ldflags = append(ldflags, cfg.BuildLdflags...)
 	cxx := false
 	for _, a := range allactions {
-		if a.p != nil && (len(a.p.CXXFiles) > 0 || len(a.p.SwigCXXFiles) > 0) {
+		if a.Package != nil && (len(a.Package.CXXFiles) > 0 || len(a.Package.SwigCXXFiles) > 0) {
 			cxx = true
 		}
 	}
@@ -2656,58 +2591,71 @@
 	// Else, use the CC environment variable and defaultCC as fallback.
 	var compiler []string
 	if cxx {
-		compiler = envList("CXX", defaultCXX)
+		compiler = envList("CXX", cfg.DefaultCXX)
 	} else {
-		compiler = envList("CC", defaultCC)
+		compiler = envList("CC", cfg.DefaultCC)
 	}
 	ldflags = setextld(ldflags, compiler)
 	for _, d := range toplevelactions {
-		if !strings.HasSuffix(d.target, ".a") { // omit unsafe etc and actions for other shared libraries
+		if !strings.HasSuffix(d.Target, ".a") { // omit unsafe etc and actions for other shared libraries
 			continue
 		}
-		ldflags = append(ldflags, d.p.ImportPath+"="+d.target)
+		ldflags = append(ldflags, d.Package.ImportPath+"="+d.Target)
 	}
-	return b.run(".", out, nil, buildToolExec, tool("link"), "-o", out, importArgs, ldflags)
+	return b.run(".", out, nil, cfg.BuildToolexec, base.Tool("link"), "-o", out, importArgs, ldflags)
 }
 
-func (gcToolchain) cc(b *builder, p *Package, objdir, ofile, cfile string) error {
+func (gcToolchain) cc(b *Builder, p *load.Package, objdir, ofile, cfile string) error {
 	return fmt.Errorf("%s: C source files not supported without cgo", mkAbs(p.Dir, cfile))
 }
 
 // The Gccgo toolchain.
 type gccgoToolchain struct{}
 
-var gccgoName, gccgoBin string
+var GccgoName, GccgoBin string
+var gccgoErr error
 
 func init() {
-	gccgoName = os.Getenv("GCCGO")
-	if gccgoName == "" {
-		gccgoName = defaultGCCGO
+	GccgoName = os.Getenv("GCCGO")
+	if GccgoName == "" {
+		GccgoName = cfg.DefaultGCCGO
 	}
-	gccgoBin, _ = exec.LookPath(gccgoName)
+	GccgoBin, gccgoErr = exec.LookPath(GccgoName)
 }
 
 func (gccgoToolchain) compiler() string {
-	return gccgoBin
+	checkGccgoBin()
+	return GccgoBin
 }
 
 func (gccgoToolchain) linker() string {
-	return gccgoBin
+	checkGccgoBin()
+	return GccgoBin
 }
 
-func (tools gccgoToolchain) gc(b *builder, p *Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, output []byte, err error) {
+func checkGccgoBin() {
+	if gccgoErr == nil {
+		return
+	}
+	fmt.Fprintf(os.Stderr, "cmd/go: gccgo: %s\n", gccgoErr)
+	os.Exit(2)
+}
+
+func (tools gccgoToolchain) gc(b *Builder, p *load.Package, archive, obj string, asmhdr bool, importArgs []string, gofiles []string) (ofile string, output []byte, err error) {
 	out := "_go_.o"
 	ofile = obj + out
 	gcargs := []string{"-g"}
 	gcargs = append(gcargs, b.gccArchArgs()...)
-	gcargs = append(gcargs, "-fdebug-prefix-map="+b.work+"=/tmp/go-build")
+	gcargs = append(gcargs, "-fdebug-prefix-map="+b.WorkDir+"=/tmp/go-build")
 	gcargs = append(gcargs, "-gno-record-gcc-switches")
 	if pkgpath := gccgoPkgpath(p); pkgpath != "" {
 		gcargs = append(gcargs, "-fgo-pkgpath="+pkgpath)
 	}
-	if p.localPrefix != "" {
-		gcargs = append(gcargs, "-fgo-relative-import-path="+p.localPrefix)
+	if p.Internal.LocalPrefix != "" {
+		gcargs = append(gcargs, "-fgo-relative-import-path="+p.Internal.LocalPrefix)
 	}
+
+	// Handle vendor directories
 	savedirs := []string{}
 	for _, incdir := range importArgs {
 		if incdir != "-I" {
@@ -2720,7 +2668,7 @@
 		if i := strings.LastIndex(path, "/vendor/"); i >= 0 {
 			for _, dir := range savedirs {
 				// Check if the vendor path is already included in dir
-				if strings.HasSuffix(dir, path[:i+len("/vendor/")]) {
+				if strings.HasSuffix(dir, path[:i+len("/vendor")]) {
 					continue
 				}
 				// Make sure this vendor path is not already in the list for importArgs
@@ -2757,7 +2705,7 @@
 		}
 	}
 
-	args := stringList(tools.compiler(), importArgs, "-c", gcargs, "-o", ofile, buildGccgoflags)
+	args := str.StringList(tools.compiler(), importArgs, "-c", gcargs, "-o", ofile, buildGccgoflags)
 	for _, f := range gofiles {
 		args = append(args, mkAbs(p.Dir, f))
 	}
@@ -2766,13 +2714,13 @@
 	return ofile, output, err
 }
 
-func (tools gccgoToolchain) asm(b *builder, p *Package, obj string, sfiles []string) ([]string, error) {
+func (tools gccgoToolchain) asm(b *Builder, p *load.Package, obj string, sfiles []string) ([]string, error) {
 	var ofiles []string
 	for _, sfile := range sfiles {
 		ofile := obj + sfile[:len(sfile)-len(".s")] + ".o"
 		ofiles = append(ofiles, ofile)
 		sfile = mkAbs(p.Dir, sfile)
-		defs := []string{"-D", "GOOS_" + goos, "-D", "GOARCH_" + goarch}
+		defs := []string{"-D", "GOOS_" + cfg.Goos, "-D", "GOARCH_" + cfg.Goarch}
 		if pkgpath := gccgoCleanPkgpath(p); pkgpath != "" {
 			defs = append(defs, `-D`, `GOPKGPATH=`+pkgpath)
 		}
@@ -2786,14 +2734,14 @@
 	return ofiles, nil
 }
 
-func (gccgoToolchain) pkgpath(basedir string, p *Package) string {
+func (gccgoToolchain) Pkgpath(basedir string, p *load.Package) string {
 	end := filepath.FromSlash(p.ImportPath + ".a")
 	afile := filepath.Join(basedir, end)
 	// add "lib" to the final element
 	return filepath.Join(filepath.Dir(afile), "lib"+filepath.Base(afile))
 }
 
-func (gccgoToolchain) pack(b *builder, p *Package, objDir, afile string, ofiles []string) error {
+func (gccgoToolchain) pack(b *Builder, p *load.Package, objDir, afile string, ofiles []string) error {
 	var absOfiles []string
 	for _, f := range ofiles {
 		absOfiles = append(absOfiles, mkAbs(objDir, f))
@@ -2806,7 +2754,7 @@
 	return nil
 }
 
-func (tools gccgoToolchain) link(b *builder, root *action, out string, allactions []*action, mainpkg string, ofiles []string, buildmode, desc string) error {
+func (tools gccgoToolchain) link(b *Builder, root *Action, out string, allactions []*Action, mainpkg string, ofiles []string, buildmode, desc string) error {
 	// gccgo needs explicit linking with all package dependencies,
 	// and all LDFLAGS from cgo dependencies.
 	apackagePathsSeen := make(map[string]bool)
@@ -2818,10 +2766,10 @@
 	cxx := false
 	objc := false
 	fortran := false
-	if root.p != nil {
-		cxx = len(root.p.CXXFiles) > 0 || len(root.p.SwigCXXFiles) > 0
-		objc = len(root.p.MFiles) > 0
-		fortran = len(root.p.FFiles) > 0
+	if root.Package != nil {
+		cxx = len(root.Package.CXXFiles) > 0 || len(root.Package.SwigCXXFiles) > 0
+		objc = len(root.Package.MFiles) > 0
+		fortran = len(root.Package.FFiles) > 0
 	}
 
 	readCgoFlags := func(flagsFile string) error {
@@ -2832,14 +2780,35 @@
 		const ldflagsPrefix = "_CGO_LDFLAGS="
 		for _, line := range strings.Split(string(flags), "\n") {
 			if strings.HasPrefix(line, ldflagsPrefix) {
-				newFlags := strings.Fields(line[len(ldflagsPrefix):])
-				for _, flag := range newFlags {
-					// Every _cgo_flags file has -g and -O2 in _CGO_LDFLAGS
-					// but they don't mean anything to the linker so filter
-					// them out.
-					if flag != "-g" && !strings.HasPrefix(flag, "-O") {
-						cgoldflags = append(cgoldflags, flag)
+				line = line[len(ldflagsPrefix):]
+				quote := byte(0)
+				start := true
+				var nl []byte
+				for len(line) > 0 {
+					b := line[0]
+					line = line[1:]
+					if quote == 0 && (b == ' ' || b == '\t') {
+						if len(nl) > 0 {
+							cgoldflags = append(cgoldflags, string(nl))
+							nl = nil
+						}
+						start = true
+						continue
+					} else if b == '"' || b == '\'' {
+						quote = b
+					} else if b == quote {
+						quote = 0
+					} else if quote == 0 && start && b == '-' && strings.HasPrefix(line, "g") {
+						line = line[1:]
+						continue
+					} else if quote == 0 && start && b == '-' && strings.HasPrefix(line, "O") {
+						for len(line) > 0 && line[0] != ' ' && line[0] != '\t' {
+							line = line[1:]
+						}
+						continue
 					}
+					nl = append(nl, b)
+					start = false
 				}
 			}
 		}
@@ -2847,7 +2816,7 @@
 	}
 
 	readAndRemoveCgoFlags := func(archive string) (string, error) {
-		newa, err := ioutil.TempFile(b.work, filepath.Base(archive))
+		newa, err := ioutil.TempFile(b.WorkDir, filepath.Base(archive))
 		if err != nil {
 			return "", err
 		}
@@ -2869,7 +2838,7 @@
 		}
 
 		newarchive := newa.Name()
-		err = b.run(b.work, desc, nil, "ar", "x", newarchive, "_cgo_flags")
+		err = b.run(b.WorkDir, desc, nil, "ar", "x", newarchive, "_cgo_flags")
 		if err != nil {
 			return "", err
 		}
@@ -2877,27 +2846,27 @@
 		if err != nil {
 			return "", err
 		}
-		err = readCgoFlags(filepath.Join(b.work, "_cgo_flags"))
+		err = readCgoFlags(filepath.Join(b.WorkDir, "_cgo_flags"))
 		if err != nil {
 			return "", err
 		}
 		return newarchive, nil
 	}
 
-	actionsSeen := make(map[*action]bool)
+	actionsSeen := make(map[*Action]bool)
 	// Make a pre-order depth-first traversal of the action graph, taking note of
 	// whether a shared library action has been seen on the way to an action (the
 	// construction of the graph means that if any path to a node passes through
 	// a shared library action, they all do).
-	var walk func(a *action, seenShlib bool)
+	var walk func(a *Action, seenShlib bool)
 	var err error
-	walk = func(a *action, seenShlib bool) {
+	walk = func(a *Action, seenShlib bool) {
 		if actionsSeen[a] {
 			return
 		}
 		actionsSeen[a] = true
-		if a.p != nil && !seenShlib {
-			if a.p.Standard {
+		if a.Package != nil && !seenShlib {
+			if a.Package.Standard {
 				return
 			}
 			// We record the target of the first time we see a .a file
@@ -2905,12 +2874,12 @@
 			// rather than the 'build' location (which may not exist any
 			// more). We still need to traverse the dependencies of the
 			// build action though so saying
-			// if apackagePathsSeen[a.p.ImportPath] { return }
+			// if apackagePathsSeen[a.Package.ImportPath] { return }
 			// doesn't work.
-			if !apackagePathsSeen[a.p.ImportPath] {
-				apackagePathsSeen[a.p.ImportPath] = true
-				target := a.target
-				if len(a.p.CgoFiles) > 0 || a.p.usesSwig() {
+			if !apackagePathsSeen[a.Package.ImportPath] {
+				apackagePathsSeen[a.Package.ImportPath] = true
+				target := a.Target
+				if len(a.Package.CgoFiles) > 0 || a.Package.UsesSwig() {
 					target, err = readAndRemoveCgoFlags(target)
 					if err != nil {
 						return
@@ -2919,18 +2888,18 @@
 				afiles = append(afiles, target)
 			}
 		}
-		if strings.HasSuffix(a.target, ".so") {
-			shlibs = append(shlibs, a.target)
+		if strings.HasSuffix(a.Target, ".so") {
+			shlibs = append(shlibs, a.Target)
 			seenShlib = true
 		}
-		for _, a1 := range a.deps {
+		for _, a1 := range a.Deps {
 			walk(a1, seenShlib)
 			if err != nil {
 				return
 			}
 		}
 	}
-	for _, a1 := range root.deps {
+	for _, a1 := range root.Deps {
 		walk(a1, false)
 		if err != nil {
 			return err
@@ -2942,25 +2911,25 @@
 		// The go tool can dig up runtime/cgo from GOROOT and
 		// think that it should use its CgoLDFLAGS, but gccgo
 		// doesn't use runtime/cgo.
-		if a.p == nil {
+		if a.Package == nil {
 			continue
 		}
-		if !a.p.Standard {
-			cgoldflags = append(cgoldflags, a.p.CgoLDFLAGS...)
+		if !a.Package.Standard {
+			cgoldflags = append(cgoldflags, a.Package.CgoLDFLAGS...)
 		}
-		if len(a.p.CgoFiles) > 0 {
+		if len(a.Package.CgoFiles) > 0 {
 			usesCgo = true
 		}
-		if a.p.usesSwig() {
+		if a.Package.UsesSwig() {
 			usesCgo = true
 		}
-		if len(a.p.CXXFiles) > 0 || len(a.p.SwigCXXFiles) > 0 {
+		if len(a.Package.CXXFiles) > 0 || len(a.Package.SwigCXXFiles) > 0 {
 			cxx = true
 		}
-		if len(a.p.MFiles) > 0 {
+		if len(a.Package.MFiles) > 0 {
 			objc = true
 		}
-		if len(a.p.FFiles) > 0 {
+		if len(a.Package.FFiles) > 0 {
 			fortran = true
 		}
 	}
@@ -2979,11 +2948,11 @@
 
 	ldflags = append(ldflags, cgoldflags...)
 	ldflags = append(ldflags, envList("CGO_LDFLAGS", "")...)
-	if root.p != nil {
-		ldflags = append(ldflags, root.p.CgoLDFLAGS...)
+	if root.Package != nil {
+		ldflags = append(ldflags, root.Package.CgoLDFLAGS...)
 	}
 
-	ldflags = stringList("-Wl,-(", ldflags, "-Wl,-)")
+	ldflags = str.StringList("-Wl,-(", ldflags, "-Wl,-)")
 
 	for _, shlib := range shlibs {
 		ldflags = append(
@@ -2998,7 +2967,7 @@
 	var realOut string
 	switch buildmode {
 	case "exe":
-		if usesCgo && goos == "linux" {
+		if usesCgo && cfg.Goos == "linux" {
 			ldflags = append(ldflags, "-Wl,-E")
 		}
 
@@ -3019,8 +2988,8 @@
 		// libffi.
 		ldflags = append(ldflags, "-Wl,-r", "-nostdlib", "-Wl,--whole-archive", "-lgolibbegin", "-Wl,--no-whole-archive")
 
-		if b.gccSupportsNoPie() {
-			ldflags = append(ldflags, "-no-pie")
+		if nopie := b.gccNoPie(); nopie != "" {
+			ldflags = append(ldflags, nopie)
 		}
 
 		// We are creating an object file, so we don't want a build ID.
@@ -3037,7 +3006,7 @@
 		ldflags = append(ldflags, "-pie")
 
 	default:
-		fatalf("-buildmode=%s not supported for gccgo", buildmode)
+		base.Fatalf("-buildmode=%s not supported for gccgo", buildmode)
 	}
 
 	switch buildmode {
@@ -3074,20 +3043,20 @@
 	return nil
 }
 
-func (tools gccgoToolchain) ld(b *builder, root *action, out string, allactions []*action, mainpkg string, ofiles []string) error {
-	return tools.link(b, root, out, allactions, mainpkg, ofiles, ldBuildmode, root.p.ImportPath)
+func (tools gccgoToolchain) ld(b *Builder, root *Action, out string, allactions []*Action, mainpkg string, ofiles []string) error {
+	return tools.link(b, root, out, allactions, mainpkg, ofiles, ldBuildmode, root.Package.ImportPath)
 }
 
-func (tools gccgoToolchain) ldShared(b *builder, toplevelactions []*action, out string, allactions []*action) error {
-	fakeRoot := &action{}
-	fakeRoot.deps = toplevelactions
+func (tools gccgoToolchain) ldShared(b *Builder, toplevelactions []*Action, out string, allactions []*Action) error {
+	fakeRoot := &Action{}
+	fakeRoot.Deps = toplevelactions
 	return tools.link(b, fakeRoot, out, allactions, "", nil, "shared", out)
 }
 
-func (tools gccgoToolchain) cc(b *builder, p *Package, objdir, ofile, cfile string) error {
-	inc := filepath.Join(goroot, "pkg", "include")
+func (tools gccgoToolchain) cc(b *Builder, p *load.Package, objdir, ofile, cfile string) error {
+	inc := filepath.Join(cfg.GOROOT, "pkg", "include")
 	cfile = mkAbs(p.Dir, cfile)
-	defs := []string{"-D", "GOOS_" + goos, "-D", "GOARCH_" + goarch}
+	defs := []string{"-D", "GOOS_" + cfg.Goos, "-D", "GOARCH_" + cfg.Goarch}
 	defs = append(defs, b.gccArchArgs()...)
 	if pkgpath := gccgoCleanPkgpath(p); pkgpath != "" {
 		defs = append(defs, `-D`, `GOPKGPATH="`+pkgpath+`"`)
@@ -3097,32 +3066,32 @@
 	}
 	defs = tools.maybePIC(defs)
 	if b.gccSupportsFlag("-fdebug-prefix-map=a=b") {
-		defs = append(defs, "-fdebug-prefix-map="+b.work+"=/tmp/go-build")
+		defs = append(defs, "-fdebug-prefix-map="+b.WorkDir+"=/tmp/go-build")
 	}
 	if b.gccSupportsFlag("-gno-record-gcc-switches") {
 		defs = append(defs, "-gno-record-gcc-switches")
 	}
-	return b.run(p.Dir, p.ImportPath, nil, envList("CC", defaultCC), "-Wall", "-g",
+	return b.run(p.Dir, p.ImportPath, nil, envList("CC", cfg.DefaultCC), "-Wall", "-g",
 		"-I", objdir, "-I", inc, "-o", ofile, defs, "-c", cfile)
 }
 
 // maybePIC adds -fPIC to the list of arguments if needed.
 func (tools gccgoToolchain) maybePIC(args []string) []string {
-	switch buildBuildmode {
+	switch cfg.BuildBuildmode {
 	case "c-archive", "c-shared", "shared", "plugin":
 		args = append(args, "-fPIC")
 	}
 	return args
 }
 
-func gccgoPkgpath(p *Package) string {
-	if p.build.IsCommand() && !p.forceLibrary {
+func gccgoPkgpath(p *load.Package) string {
+	if p.Internal.Build.IsCommand() && !p.Internal.ForceLibrary {
 		return ""
 	}
 	return p.ImportPath
 }
 
-func gccgoCleanPkgpath(p *Package) string {
+func gccgoCleanPkgpath(p *load.Package) string {
 	clean := func(r rune) rune {
 		switch {
 		case 'A' <= r && r <= 'Z', 'a' <= r && r <= 'z',
@@ -3135,25 +3104,28 @@
 }
 
 // gcc runs the gcc C compiler to create an object from a single C file.
-func (b *builder) gcc(p *Package, out string, flags []string, cfile string) error {
-	return b.ccompile(p, out, flags, cfile, b.gccCmd(p.Dir))
+func (b *Builder) gcc(p *load.Package, out string, flags []string, cfile string) error {
+	return b.ccompile(p, out, flags, cfile, b.GccCmd(p.Dir))
 }
 
 // gxx runs the g++ C++ compiler to create an object from a single C++ file.
-func (b *builder) gxx(p *Package, out string, flags []string, cxxfile string) error {
-	return b.ccompile(p, out, flags, cxxfile, b.gxxCmd(p.Dir))
+func (b *Builder) gxx(p *load.Package, out string, flags []string, cxxfile string) error {
+	return b.ccompile(p, out, flags, cxxfile, b.GxxCmd(p.Dir))
 }
 
 // gfortran runs the gfortran Fortran compiler to create an object from a single Fortran file.
-func (b *builder) gfortran(p *Package, out string, flags []string, ffile string) error {
+func (b *Builder) gfortran(p *load.Package, out string, flags []string, ffile string) error {
 	return b.ccompile(p, out, flags, ffile, b.gfortranCmd(p.Dir))
 }
 
 // ccompile runs the given C or C++ compiler and creates an object from a single source file.
-func (b *builder) ccompile(p *Package, outfile string, flags []string, file string, compiler []string) error {
+func (b *Builder) ccompile(p *load.Package, outfile string, flags []string, file string, compiler []string) error {
 	file = mkAbs(p.Dir, file)
 	desc := p.ImportPath
-	output, err := b.runOut(p.Dir, desc, nil, compiler, flags, "-o", outfile, "-c", file)
+	if !filepath.IsAbs(outfile) {
+		outfile = filepath.Join(p.Dir, outfile)
+	}
+	output, err := b.runOut(filepath.Dir(file), desc, nil, compiler, flags, "-o", outfile, "-c", filepath.Base(file))
 	if len(output) > 0 {
 		// On FreeBSD 11, when we pass -g to clang 3.8 it
 		// invokes its internal assembler with -dwarf-version=2.
@@ -3186,36 +3158,36 @@
 }
 
 // gccld runs the gcc linker to create an executable from a set of object files.
-func (b *builder) gccld(p *Package, out string, flags []string, obj []string) error {
+func (b *Builder) gccld(p *load.Package, out string, flags []string, obj []string) error {
 	var cmd []string
 	if len(p.CXXFiles) > 0 || len(p.SwigCXXFiles) > 0 {
-		cmd = b.gxxCmd(p.Dir)
+		cmd = b.GxxCmd(p.Dir)
 	} else {
-		cmd = b.gccCmd(p.Dir)
+		cmd = b.GccCmd(p.Dir)
 	}
 	return b.run(p.Dir, p.ImportPath, nil, cmd, "-o", out, obj, flags)
 }
 
 // gccCmd returns a gcc command line prefix
 // defaultCC is defined in zdefaultcc.go, written by cmd/dist.
-func (b *builder) gccCmd(objdir string) []string {
-	return b.ccompilerCmd("CC", defaultCC, objdir)
+func (b *Builder) GccCmd(objdir string) []string {
+	return b.ccompilerCmd("CC", cfg.DefaultCC, objdir)
 }
 
 // gxxCmd returns a g++ command line prefix
 // defaultCXX is defined in zdefaultcc.go, written by cmd/dist.
-func (b *builder) gxxCmd(objdir string) []string {
-	return b.ccompilerCmd("CXX", defaultCXX, objdir)
+func (b *Builder) GxxCmd(objdir string) []string {
+	return b.ccompilerCmd("CXX", cfg.DefaultCXX, objdir)
 }
 
 // gfortranCmd returns a gfortran command line prefix.
-func (b *builder) gfortranCmd(objdir string) []string {
+func (b *Builder) gfortranCmd(objdir string) []string {
 	return b.ccompilerCmd("FC", "gfortran", objdir)
 }
 
 // ccompilerCmd returns a command line prefix for the given environment
 // variable and using the default command when the variable is empty.
-func (b *builder) ccompilerCmd(envvar, defcmd, objdir string) []string {
+func (b *Builder) ccompilerCmd(envvar, defcmd, objdir string) []string {
 	// NOTE: env.go's mkEnv knows that the first three
 	// strings returned are "gcc", "-I", objdir (and cuts them off).
 
@@ -3225,14 +3197,14 @@
 
 	// Definitely want -fPIC but on Windows gcc complains
 	// "-fPIC ignored for target (all code is position independent)"
-	if goos != "windows" {
+	if cfg.Goos != "windows" {
 		a = append(a, "-fPIC")
 	}
 	a = append(a, b.gccArchArgs()...)
 	// gcc-4.5 and beyond require explicit "-pthread" flag
 	// for multithreading with pthread library.
-	if buildContext.CgoEnabled {
-		switch goos {
+	if cfg.BuildContext.CgoEnabled {
+		switch cfg.Goos {
 		case "windows":
 			a = append(a, "-mthreads")
 		default:
@@ -3252,7 +3224,7 @@
 
 	// Tell gcc not to include the work directory in object files.
 	if b.gccSupportsFlag("-fdebug-prefix-map=a=b") {
-		a = append(a, "-fdebug-prefix-map="+b.work+"=/tmp/go-build")
+		a = append(a, "-fdebug-prefix-map="+b.WorkDir+"=/tmp/go-build")
 	}
 
 	// Tell gcc not to include flags in object files, which defeats the
@@ -3264,50 +3236,57 @@
 	// On OS X, some of the compilers behave as if -fno-common
 	// is always set, and the Mach-O linker in 6l/8l assumes this.
 	// See https://golang.org/issue/3253.
-	if goos == "darwin" {
+	if cfg.Goos == "darwin" {
 		a = append(a, "-fno-common")
 	}
 
 	// gccgo uses the language-independent exception mechanism to
 	// handle panics, so it always needs unwind tables.
-	if _, ok := buildToolchain.(gccgoToolchain); ok {
+	if cfg.BuildToolchainName == "gccgo" {
 		a = append(a, "-funwind-tables")
 	}
 
 	return a
 }
 
-// On systems with PIE (position independent executables) enabled by default,
-// -no-pie must be passed when doing a partial link with -Wl,-r. But -no-pie is
-// not supported by all compilers.
-func (b *builder) gccSupportsNoPie() bool {
-	return b.gccSupportsFlag("-no-pie")
+// gccNoPie returns the flag to use to request non-PIE. On systems
+// with PIE (position independent executables) enabled by default,
+// -no-pie must be passed when doing a partial link with -Wl,-r.
+// But -no-pie is not supported by all compilers, and clang spells it -nopie.
+func (b *Builder) gccNoPie() string {
+	if b.gccSupportsFlag("-no-pie") {
+		return "-no-pie"
+	}
+	if b.gccSupportsFlag("-nopie") {
+		return "-nopie"
+	}
+	return ""
 }
 
 // gccSupportsFlag checks to see if the compiler supports a flag.
-func (b *builder) gccSupportsFlag(flag string) bool {
+func (b *Builder) gccSupportsFlag(flag string) bool {
 	b.exec.Lock()
 	defer b.exec.Unlock()
 	if b, ok := b.flagCache[flag]; ok {
 		return b
 	}
 	if b.flagCache == nil {
-		src := filepath.Join(b.work, "trivial.c")
+		src := filepath.Join(b.WorkDir, "trivial.c")
 		if err := ioutil.WriteFile(src, []byte{}, 0666); err != nil {
 			return false
 		}
 		b.flagCache = make(map[string]bool)
 	}
-	cmdArgs := append(envList("CC", defaultCC), flag, "-c", "trivial.c")
-	if buildN || buildX {
-		b.showcmd(b.work, "%s", joinUnambiguously(cmdArgs))
-		if buildN {
+	cmdArgs := append(envList("CC", cfg.DefaultCC), flag, "-c", "trivial.c")
+	if cfg.BuildN || cfg.BuildX {
+		b.Showcmd(b.WorkDir, "%s", joinUnambiguously(cmdArgs))
+		if cfg.BuildN {
 			return false
 		}
 	}
 	cmd := exec.Command(cmdArgs[0], cmdArgs[1:]...)
-	cmd.Dir = b.work
-	cmd.Env = mergeEnvLists([]string{"LC_ALL=C"}, envForDir(cmd.Dir, os.Environ()))
+	cmd.Dir = b.WorkDir
+	cmd.Env = base.MergeEnvLists([]string{"LC_ALL=C"}, base.EnvForDir(cmd.Dir, os.Environ()))
 	out, err := cmd.CombinedOutput()
 	supported := err == nil && !bytes.Contains(out, []byte("unrecognized"))
 	b.flagCache[flag] = supported
@@ -3315,8 +3294,8 @@
 }
 
 // gccArchArgs returns arguments to pass to gcc based on the architecture.
-func (b *builder) gccArchArgs() []string {
-	switch goarch {
+func (b *Builder) gccArchArgs() []string {
+	switch cfg.Goarch {
 	case "386":
 		return []string{"-m32"}
 	case "amd64", "amd64p32":
@@ -3343,23 +3322,23 @@
 	return strings.Fields(v)
 }
 
-// Return the flags to use when invoking the C, C++ or Fortran compilers, or cgo.
-func (b *builder) cflags(p *Package) (cppflags, cflags, cxxflags, fflags, ldflags []string) {
+// CFlags returns the flags to use when invoking the C, C++ or Fortran compilers, or cgo.
+func (b *Builder) CFlags(p *load.Package) (cppflags, cflags, cxxflags, fflags, ldflags []string) {
 	defaults := "-g -O2"
 
-	cppflags = stringList(envList("CGO_CPPFLAGS", ""), p.CgoCPPFLAGS)
-	cflags = stringList(envList("CGO_CFLAGS", defaults), p.CgoCFLAGS)
-	cxxflags = stringList(envList("CGO_CXXFLAGS", defaults), p.CgoCXXFLAGS)
-	fflags = stringList(envList("CGO_FFLAGS", defaults), p.CgoFFLAGS)
-	ldflags = stringList(envList("CGO_LDFLAGS", defaults), p.CgoLDFLAGS)
+	cppflags = str.StringList(envList("CGO_CPPFLAGS", ""), p.CgoCPPFLAGS)
+	cflags = str.StringList(envList("CGO_CFLAGS", defaults), p.CgoCFLAGS)
+	cxxflags = str.StringList(envList("CGO_CXXFLAGS", defaults), p.CgoCXXFLAGS)
+	fflags = str.StringList(envList("CGO_FFLAGS", defaults), p.CgoFFLAGS)
+	ldflags = str.StringList(envList("CGO_LDFLAGS", defaults), p.CgoLDFLAGS)
 	return
 }
 
 var cgoRe = regexp.MustCompile(`[/\\:]`)
 
-func (b *builder) cgo(a *action, cgoExe, obj string, pcCFLAGS, pcLDFLAGS, cgofiles, objdirCgofiles, gccfiles, gxxfiles, mfiles, ffiles []string) (outGo, outObj []string, err error) {
-	p := a.p
-	cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, cgoFFLAGS, cgoLDFLAGS := b.cflags(p)
+func (b *Builder) cgo(a *Action, cgoExe, obj string, pcCFLAGS, pcLDFLAGS, cgofiles, objdirCgofiles, gccfiles, gxxfiles, mfiles, ffiles []string) (outGo, outObj []string, err error) {
+	p := a.Package
+	cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, cgoFFLAGS, cgoLDFLAGS := b.CFlags(p)
 	cgoCPPFLAGS = append(cgoCPPFLAGS, pcCFLAGS...)
 	cgoLDFLAGS = append(cgoLDFLAGS, pcLDFLAGS...)
 	// If we are compiling Objective-C code, then we need to link against libobjc
@@ -3380,7 +3359,7 @@
 		}
 	}
 
-	if buildMSan {
+	if cfg.BuildMSan {
 		cgoCFLAGS = append([]string{"-fsanitize=memory"}, cgoCFLAGS...)
 		cgoLDFLAGS = append([]string{"-fsanitize=memory"}, cgoLDFLAGS...)
 	}
@@ -3432,7 +3411,7 @@
 		cgoenv = []string{"CGO_LDFLAGS=" + strings.Join(flags, " ")}
 	}
 
-	if _, ok := buildToolchain.(gccgoToolchain); ok {
+	if cfg.BuildToolchainName == "gccgo" {
 		if b.gccSupportsFlag("-fsplit-stack") {
 			cgoCFLAGS = append(cgoCFLAGS, "-fsplit-stack")
 		}
@@ -3442,7 +3421,7 @@
 		}
 	}
 
-	switch buildBuildmode {
+	switch cfg.BuildBuildmode {
 	case "c-archive", "c-shared":
 		// Tell cgo that if there are any exported functions
 		// it should generate a header file that C code can
@@ -3450,13 +3429,13 @@
 		cgoflags = append(cgoflags, "-exportheader="+obj+"_cgo_install.h")
 	}
 
-	if err := b.run(p.Dir, p.ImportPath, cgoenv, buildToolExec, cgoExe, srcdirarg, "-objdir", obj, "-importpath", p.ImportPath, cgoflags, "--", cgoCPPFLAGS, cgoCFLAGS, cgofiles); err != nil {
+	if err := b.run(p.Dir, p.ImportPath, cgoenv, cfg.BuildToolexec, cgoExe, srcdirarg, "-objdir", obj, "-importpath", p.ImportPath, cgoflags, "--", cgoCPPFLAGS, cgoCFLAGS, cgofiles); err != nil {
 		return nil, nil, err
 	}
 	outGo = append(outGo, gofiles...)
 
 	// gcc
-	cflags := stringList(cgoCPPFLAGS, cgoCFLAGS)
+	cflags := str.StringList(cgoCPPFLAGS, cgoCFLAGS)
 	for _, cfile := range cfiles {
 		ofile := obj + cfile[:len(cfile)-1] + "o"
 		if err := b.gcc(p, ofile, cflags, obj+cfile); err != nil {
@@ -3474,7 +3453,7 @@
 		outObj = append(outObj, ofile)
 	}
 
-	cxxflags := stringList(cgoCPPFLAGS, cgoCXXFLAGS)
+	cxxflags := str.StringList(cgoCPPFLAGS, cgoCXXFLAGS)
 	for _, file := range gxxfiles {
 		// Append .o to the file, just in case the pkg has file.c and file.cpp
 		ofile := obj + cgoRe.ReplaceAllString(filepath.Base(file), "_") + ".o"
@@ -3493,7 +3472,7 @@
 		outObj = append(outObj, ofile)
 	}
 
-	fflags := stringList(cgoCPPFLAGS, cgoFFLAGS)
+	fflags := str.StringList(cgoCPPFLAGS, cgoFFLAGS)
 	for _, file := range ffiles {
 		// Append .o to the file, just in case the pkg has file.c and file.f
 		ofile := obj + cgoRe.ReplaceAllString(filepath.Base(file), "_") + ".o"
@@ -3503,8 +3482,8 @@
 		outObj = append(outObj, ofile)
 	}
 
-	switch buildToolchain.(type) {
-	case gcToolchain:
+	switch cfg.BuildToolchainName {
+	case "gc":
 		importGo := obj + "_cgo_import.go"
 		if err := b.dynimport(p, obj, importGo, cgoExe, cflags, cgoLDFLAGS, outObj); err != nil {
 			return nil, nil, err
@@ -3517,10 +3496,10 @@
 		}
 		outObj = []string{ofile}
 
-	case gccgoToolchain:
+	case "gccgo":
 		defunC := obj + "_cgo_defun.c"
 		defunObj := obj + "_cgo_defun.o"
-		if err := buildToolchain.cc(b, p, obj, defunObj, defunC); err != nil {
+		if err := BuildToolchain.cc(b, p, obj, defunObj, defunC); err != nil {
 			return nil, nil, err
 		}
 		outObj = append(outObj, defunObj)
@@ -3535,19 +3514,19 @@
 // dynimport creates a Go source file named importGo containing
 // //go:cgo_import_dynamic directives for each symbol or library
 // dynamically imported by the object files outObj.
-func (b *builder) dynimport(p *Package, obj, importGo, cgoExe string, cflags, cgoLDFLAGS, outObj []string) error {
+func (b *Builder) dynimport(p *load.Package, obj, importGo, cgoExe string, cflags, cgoLDFLAGS, outObj []string) error {
 	cfile := obj + "_cgo_main.c"
 	ofile := obj + "_cgo_main.o"
 	if err := b.gcc(p, ofile, cflags, cfile); err != nil {
 		return err
 	}
 
-	linkobj := stringList(ofile, outObj, p.SysoFiles)
+	linkobj := str.StringList(ofile, outObj, p.SysoFiles)
 	dynobj := obj + "_cgo_.o"
 
 	// we need to use -pie for Linux/ARM to get accurate imported sym
 	ldflags := cgoLDFLAGS
-	if (goarch == "arm" && goos == "linux") || goos == "android" {
+	if (cfg.Goarch == "arm" && cfg.Goos == "linux") || cfg.Goos == "android" {
 		ldflags = append(ldflags, "-pie")
 	}
 	if err := b.gccld(p, dynobj, ldflags, linkobj); err != nil {
@@ -3559,12 +3538,12 @@
 	if p.Standard && p.ImportPath == "runtime/cgo" {
 		cgoflags = []string{"-dynlinker"} // record path to dynamic linker
 	}
-	return b.run(p.Dir, p.ImportPath, nil, buildToolExec, cgoExe, "-dynpackage", p.Name, "-dynimport", dynobj, "-dynout", importGo, cgoflags)
+	return b.run(p.Dir, p.ImportPath, nil, cfg.BuildToolexec, cgoExe, "-dynpackage", p.Name, "-dynimport", dynobj, "-dynout", importGo, cgoflags)
 }
 
 // collect partially links the object files outObj into a single
 // relocatable object file named ofile.
-func (b *builder) collect(p *Package, obj, ofile string, cgoLDFLAGS, outObj []string) error {
+func (b *Builder) collect(p *load.Package, obj, ofile string, cgoLDFLAGS, outObj []string) error {
 	// When linking relocatable objects, various flags need to be
 	// filtered out as they are inapplicable and can cause some linkers
 	// to fail.
@@ -3578,7 +3557,7 @@
 				i++
 			}
 		// skip "-framework X" on Darwin
-		case goos == "darwin" && f == "-framework":
+		case cfg.Goos == "darwin" && f == "-framework":
 			i++
 		// skip "*.{dylib,so,dll,o,a}"
 		case strings.HasSuffix(f, ".dylib"),
@@ -3611,8 +3590,8 @@
 
 	ldflags = append(ldflags, "-Wl,-r", "-nostdlib")
 
-	if b.gccSupportsNoPie() {
-		ldflags = append(ldflags, "-no-pie")
+	if flag := b.gccNoPie(); flag != "" {
+		ldflags = append(ldflags, flag)
 	}
 
 	// We are creating an object file, so we don't want a build ID.
@@ -3624,7 +3603,7 @@
 // Run SWIG on all SWIG input files.
 // TODO: Don't build a shared library, once SWIG emits the necessary
 // pragmas for external linking.
-func (b *builder) swig(p *Package, obj string, pcCFLAGS []string) (outGo, outC, outCXX []string, err error) {
+func (b *Builder) swig(p *load.Package, obj string, pcCFLAGS []string) (outGo, outC, outCXX []string, err error) {
 	if err := b.swigVersionCheck(); err != nil {
 		return nil, nil, nil, err
 	}
@@ -3667,7 +3646,7 @@
 	swigCheck     error
 )
 
-func (b *builder) swigDoVersionCheck() error {
+func (b *Builder) swigDoVersionCheck() error {
 	out, err := b.runOut("", "", nil, "swig", "-version")
 	if err != nil {
 		return err
@@ -3720,7 +3699,7 @@
 	return nil
 }
 
-func (b *builder) swigVersionCheck() error {
+func (b *Builder) swigVersionCheck() error {
 	swigCheckOnce.Do(func() {
 		swigCheck = b.swigDoVersionCheck()
 	})
@@ -3741,20 +3720,20 @@
 `
 
 // Determine the size of int on the target system for the -intgosize option
-// of swig >= 2.0.9.  Run only once.
-func (b *builder) swigDoIntSize(obj string) (intsize string, err error) {
-	if buildN {
+// of swig >= 2.0.9. Run only once.
+func (b *Builder) swigDoIntSize(obj string) (intsize string, err error) {
+	if cfg.BuildN {
 		return "$INTBITS", nil
 	}
-	src := filepath.Join(b.work, "swig_intsize.go")
+	src := filepath.Join(b.WorkDir, "swig_intsize.go")
 	if err = ioutil.WriteFile(src, []byte(swigIntSizeCode), 0666); err != nil {
 		return
 	}
 	srcs := []string{src}
 
-	p := goFilesPackage(srcs)
+	p := load.GoFilesPackage(srcs)
 
-	if _, _, e := buildToolchain.gc(b, p, "", obj, false, nil, srcs); e != nil {
+	if _, _, e := BuildToolchain.gc(b, p, "", obj, false, nil, srcs); e != nil {
 		return "32", nil
 	}
 	return "64", nil
@@ -3762,7 +3741,7 @@
 
 // Determine the size of int on the target system for the -intgosize option
 // of swig >= 2.0.9.
-func (b *builder) swigIntSize(obj string) (intsize string, err error) {
+func (b *Builder) swigIntSize(obj string) (intsize string, err error) {
 	swigIntSizeOnce.Do(func() {
 		swigIntSize, swigIntSizeError = b.swigDoIntSize(obj)
 	})
@@ -3770,13 +3749,13 @@
 }
 
 // Run SWIG on one SWIG input file.
-func (b *builder) swigOne(p *Package, file, obj string, pcCFLAGS []string, cxx bool, intgosize string) (outGo, outC string, err error) {
-	cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, _, _ := b.cflags(p)
+func (b *Builder) swigOne(p *load.Package, file, obj string, pcCFLAGS []string, cxx bool, intgosize string) (outGo, outC string, err error) {
+	cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, _, _ := b.CFlags(p)
 	var cflags []string
 	if cxx {
-		cflags = stringList(cgoCPPFLAGS, pcCFLAGS, cgoCXXFLAGS)
+		cflags = str.StringList(cgoCPPFLAGS, pcCFLAGS, cgoCXXFLAGS)
 	} else {
-		cflags = stringList(cgoCPPFLAGS, pcCFLAGS, cgoCFLAGS)
+		cflags = str.StringList(cgoCPPFLAGS, pcCFLAGS, cgoCFLAGS)
 	}
 
 	n := 5 // length of ".swig"
@@ -3791,7 +3770,7 @@
 		gccExt = "cxx"
 	}
 
-	_, gccgo := buildToolchain.(gccgoToolchain)
+	gccgo := cfg.BuildToolchainName == "gccgo"
 
 	// swig
 	args := []string{
@@ -3847,8 +3826,8 @@
 // other than passing a trailing --build-id=none. So that is what we
 // do, but only on systems likely to support it, which is to say,
 // systems that normally use gold or the GNU linker.
-func (b *builder) disableBuildID(ldflags []string) []string {
-	switch goos {
+func (b *Builder) disableBuildID(ldflags []string) []string {
+	switch cfg.Goos {
 	case "android", "dragonfly", "linux", "netbsd":
 		ldflags = append(ldflags, "-Wl,--build-id=none")
 	}
@@ -3856,13 +3835,13 @@
 }
 
 // An actionQueue is a priority queue of actions.
-type actionQueue []*action
+type actionQueue []*Action
 
 // Implement heap.Interface
 func (q *actionQueue) Len() int           { return len(*q) }
 func (q *actionQueue) Swap(i, j int)      { (*q)[i], (*q)[j] = (*q)[j], (*q)[i] }
 func (q *actionQueue) Less(i, j int) bool { return (*q)[i].priority < (*q)[j].priority }
-func (q *actionQueue) Push(x interface{}) { *q = append(*q, x.(*action)) }
+func (q *actionQueue) Push(x interface{}) { *q = append(*q, x.(*Action)) }
 func (q *actionQueue) Pop() interface{} {
 	n := len(*q) - 1
 	x := (*q)[n]
@@ -3870,50 +3849,75 @@
 	return x
 }
 
-func (q *actionQueue) push(a *action) {
+func (q *actionQueue) push(a *Action) {
 	heap.Push(q, a)
 }
 
-func (q *actionQueue) pop() *action {
-	return heap.Pop(q).(*action)
+func (q *actionQueue) pop() *Action {
+	return heap.Pop(q).(*Action)
 }
 
-func instrumentInit() {
-	if !buildRace && !buildMSan {
+func InstrumentInit() {
+	if !cfg.BuildRace && !cfg.BuildMSan {
 		return
 	}
-	if buildRace && buildMSan {
+	if cfg.BuildRace && cfg.BuildMSan {
 		fmt.Fprintf(os.Stderr, "go %s: may not use -race and -msan simultaneously\n", flag.Args()[0])
 		os.Exit(2)
 	}
-	if buildMSan && (goos != "linux" || goarch != "amd64") {
-		fmt.Fprintf(os.Stderr, "-msan is not supported on %s/%s\n", goos, goarch)
+	if cfg.BuildMSan && (cfg.Goos != "linux" || cfg.Goarch != "amd64") {
+		fmt.Fprintf(os.Stderr, "-msan is not supported on %s/%s\n", cfg.Goos, cfg.Goarch)
 		os.Exit(2)
 	}
-	if goarch != "amd64" || goos != "linux" && goos != "freebsd" && goos != "darwin" && goos != "windows" {
+	if cfg.Goarch != "amd64" || cfg.Goos != "linux" && cfg.Goos != "freebsd" && cfg.Goos != "darwin" && cfg.Goos != "windows" {
 		fmt.Fprintf(os.Stderr, "go %s: -race and -msan are only supported on linux/amd64, freebsd/amd64, darwin/amd64 and windows/amd64\n", flag.Args()[0])
 		os.Exit(2)
 	}
-	if !buildContext.CgoEnabled {
+	if !cfg.BuildContext.CgoEnabled {
 		fmt.Fprintf(os.Stderr, "go %s: -race requires cgo; enable cgo by setting CGO_ENABLED=1\n", flag.Args()[0])
 		os.Exit(2)
 	}
-	if buildRace {
+	if cfg.BuildRace {
 		buildGcflags = append(buildGcflags, "-race")
-		buildLdflags = append(buildLdflags, "-race")
+		cfg.BuildLdflags = append(cfg.BuildLdflags, "-race")
 	} else {
 		buildGcflags = append(buildGcflags, "-msan")
-		buildLdflags = append(buildLdflags, "-msan")
+		cfg.BuildLdflags = append(cfg.BuildLdflags, "-msan")
 	}
-	if buildContext.InstallSuffix != "" {
-		buildContext.InstallSuffix += "_"
+	if cfg.BuildContext.InstallSuffix != "" {
+		cfg.BuildContext.InstallSuffix += "_"
 	}
 
-	if buildRace {
-		buildContext.InstallSuffix += "race"
-		buildContext.BuildTags = append(buildContext.BuildTags, "race")
+	if cfg.BuildRace {
+		cfg.BuildContext.InstallSuffix += "race"
+		cfg.BuildContext.BuildTags = append(cfg.BuildContext.BuildTags, "race")
 	} else {
-		buildContext.InstallSuffix += "msan"
-		buildContext.BuildTags = append(buildContext.BuildTags, "msan")
+		cfg.BuildContext.InstallSuffix += "msan"
+		cfg.BuildContext.BuildTags = append(cfg.BuildContext.BuildTags, "msan")
 	}
 }
+
+// ExecCmd is the command to use to run user binaries.
+// Normally it is empty, meaning run the binaries directly.
+// If cross-compiling and running on a remote system or
+// simulator, it is typically go_GOOS_GOARCH_exec, with
+// the target GOOS and GOARCH substituted.
+// The -exec flag overrides these defaults.
+var ExecCmd []string
+
+// FindExecCmd derives the value of ExecCmd to use.
+// It returns that value and leaves ExecCmd set for direct use.
+func FindExecCmd() []string {
+	if ExecCmd != nil {
+		return ExecCmd
+	}
+	ExecCmd = []string{} // avoid work the second time
+	if cfg.Goos == runtime.GOOS && cfg.Goarch == runtime.GOARCH {
+		return ExecCmd
+	}
+	path, err := exec.LookPath(fmt.Sprintf("go_%s_%s_exec", cfg.Goos, cfg.Goarch))
+	if err == nil {
+		ExecCmd = []string{path}
+	}
+	return ExecCmd
+}
diff --git a/libgo/go/cmd/go/internal/work/build_test.go b/libgo/go/cmd/go/internal/work/build_test.go
new file mode 100644
index 0000000..294b83c
--- /dev/null
+++ b/libgo/go/cmd/go/internal/work/build_test.go
@@ -0,0 +1,227 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package work
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"strings"
+	"testing"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+)
+
+func TestRemoveDevNull(t *testing.T) {
+	fi, err := os.Lstat(os.DevNull)
+	if err != nil {
+		t.Skip(err)
+	}
+	if fi.Mode().IsRegular() {
+		t.Errorf("Lstat(%s).Mode().IsRegular() = true; expected false", os.DevNull)
+	}
+	mayberemovefile(os.DevNull)
+	_, err = os.Lstat(os.DevNull)
+	if err != nil {
+		t.Errorf("mayberemovefile(%s) did remove it; oops", os.DevNull)
+	}
+}
+
+func TestSplitPkgConfigOutput(t *testing.T) {
+	for _, test := range []struct {
+		in   []byte
+		want []string
+	}{
+		{[]byte(`-r:foo -L/usr/white\ space/lib -lfoo\ bar -lbar\ baz`), []string{"-r:foo", "-L/usr/white space/lib", "-lfoo bar", "-lbar baz"}},
+		{[]byte(`-lextra\ fun\ arg\\`), []string{`-lextra fun arg\`}},
+		{[]byte(`broken flag\`), []string{"broken", "flag"}},
+		{[]byte("\textra     whitespace\r\n"), []string{"extra", "whitespace"}},
+		{[]byte("     \r\n      "), nil},
+	} {
+		got := splitPkgConfigOutput(test.in)
+		if !reflect.DeepEqual(got, test.want) {
+			t.Errorf("splitPkgConfigOutput(%v) = %v; want %v", test.in, got, test.want)
+		}
+	}
+}
+
+func TestSharedLibName(t *testing.T) {
+	// TODO(avdva) - make these values platform-specific
+	prefix := "lib"
+	suffix := ".so"
+	testData := []struct {
+		args      []string
+		pkgs      []*load.Package
+		expected  string
+		expectErr bool
+		rootedAt  string
+	}{
+		{
+			args:     []string{"std"},
+			pkgs:     []*load.Package{},
+			expected: "std",
+		},
+		{
+			args:     []string{"std", "cmd"},
+			pkgs:     []*load.Package{},
+			expected: "std,cmd",
+		},
+		{
+			args:     []string{},
+			pkgs:     []*load.Package{pkgImportPath("gopkg.in/somelib")},
+			expected: "gopkg.in-somelib",
+		},
+		{
+			args:     []string{"./..."},
+			pkgs:     []*load.Package{pkgImportPath("somelib")},
+			expected: "somelib",
+			rootedAt: "somelib",
+		},
+		{
+			args:     []string{"../somelib", "../somelib"},
+			pkgs:     []*load.Package{pkgImportPath("somelib")},
+			expected: "somelib",
+		},
+		{
+			args:     []string{"../lib1", "../lib2"},
+			pkgs:     []*load.Package{pkgImportPath("gopkg.in/lib1"), pkgImportPath("gopkg.in/lib2")},
+			expected: "gopkg.in-lib1,gopkg.in-lib2",
+		},
+		{
+			args: []string{"./..."},
+			pkgs: []*load.Package{
+				pkgImportPath("gopkg.in/dir/lib1"),
+				pkgImportPath("gopkg.in/lib2"),
+				pkgImportPath("gopkg.in/lib3"),
+			},
+			expected: "gopkg.in",
+			rootedAt: "gopkg.in",
+		},
+		{
+			args:      []string{"std", "../lib2"},
+			pkgs:      []*load.Package{},
+			expectErr: true,
+		},
+		{
+			args:      []string{"all", "./"},
+			pkgs:      []*load.Package{},
+			expectErr: true,
+		},
+		{
+			args:      []string{"cmd", "fmt"},
+			pkgs:      []*load.Package{},
+			expectErr: true,
+		},
+	}
+	for _, data := range testData {
+		func() {
+			if data.rootedAt != "" {
+				tmpGopath, err := ioutil.TempDir("", "gopath")
+				if err != nil {
+					t.Fatal(err)
+				}
+				oldGopath := cfg.BuildContext.GOPATH
+				defer func() {
+					cfg.BuildContext.GOPATH = oldGopath
+					os.Chdir(base.Cwd)
+					err := os.RemoveAll(tmpGopath)
+					if err != nil {
+						t.Error(err)
+					}
+				}()
+				root := filepath.Join(tmpGopath, "src", data.rootedAt)
+				err = os.MkdirAll(root, 0755)
+				if err != nil {
+					t.Fatal(err)
+				}
+				cfg.BuildContext.GOPATH = tmpGopath
+				os.Chdir(root)
+			}
+			computed, err := libname(data.args, data.pkgs)
+			if err != nil {
+				if !data.expectErr {
+					t.Errorf("libname returned an error %q, expected a name", err.Error())
+				}
+			} else if data.expectErr {
+				t.Errorf("libname returned %q, expected an error", computed)
+			} else {
+				expected := prefix + data.expected + suffix
+				if expected != computed {
+					t.Errorf("libname returned %q, expected %q", computed, expected)
+				}
+			}
+		}()
+	}
+}
+
+func pkgImportPath(pkgpath string) *load.Package {
+	return &load.Package{
+		PackagePublic: load.PackagePublic{
+			ImportPath: pkgpath,
+		},
+	}
+}
+
+// When installing packages, the installed package directory should
+// respect the SetGID bit and group name of the destination
+// directory.
+// See https://golang.org/issue/18878.
+func TestRespectSetgidDir(t *testing.T) {
+	if runtime.GOOS == "nacl" {
+		t.Skip("can't set SetGID bit with chmod on nacl")
+	}
+
+	var b Builder
+
+	// Check that `cp` is called instead of `mv` by looking at the output
+	// of `(*Builder).ShowCmd` afterwards as a sanity check.
+	cfg.BuildX = true
+	var cmdBuf bytes.Buffer
+	b.Print = func(a ...interface{}) (int, error) {
+		return cmdBuf.WriteString(fmt.Sprint(a...))
+	}
+
+	setgiddir, err := ioutil.TempDir("", "SetGroupID")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(setgiddir)
+
+	if runtime.GOOS == "freebsd" {
+		err = os.Chown(setgiddir, os.Getuid(), os.Getgid())
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	// Change setgiddir's permissions to include the SetGID bit.
+	if err := os.Chmod(setgiddir, 0755|os.ModeSetgid); err != nil {
+		t.Fatal(err)
+	}
+
+	pkgfile, err := ioutil.TempFile("", "pkgfile")
+	if err != nil {
+		t.Fatalf("ioutil.TempFile(\"\", \"pkgfile\"): %v", err)
+	}
+	defer os.Remove(pkgfile.Name())
+	defer pkgfile.Close()
+
+	dirGIDFile := filepath.Join(setgiddir, "setgid")
+	if err := b.moveOrCopyFile(nil, dirGIDFile, pkgfile.Name(), 0666, true); err != nil {
+		t.Fatalf("moveOrCopyFile: %v", err)
+	}
+
+	got := strings.TrimSpace(cmdBuf.String())
+	want := b.fmtcmd("", "cp %s %s", pkgfile.Name(), dirGIDFile)
+	if got != want {
+		t.Fatalf("moveOrCopyFile(%q, %q): want %q, got %q", dirGIDFile, pkgfile.Name(), want, got)
+	}
+}
diff --git a/libgo/go/cmd/go/internal/work/testgo.go b/libgo/go/cmd/go/internal/work/testgo.go
new file mode 100644
index 0000000..3e623c6
--- /dev/null
+++ b/libgo/go/cmd/go/internal/work/testgo.go
@@ -0,0 +1,17 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains extra hooks for testing the go command.
+
+// +build testgo
+
+package work
+
+import "os"
+
+func init() {
+	if v := os.Getenv("TESTGO_VERSION"); v != "" {
+		runtimeVersion = v
+	}
+}
diff --git a/libgo/go/cmd/go/main.go b/libgo/go/cmd/go/main.go
index ceeac4d..794ce08 100644
--- a/libgo/go/cmd/go/main.go
+++ b/libgo/go/cmd/go/main.go
@@ -2,141 +2,90 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:generate ./mkalldocs.sh
+
 package main
 
 import (
-	"bufio"
-	"bytes"
 	"flag"
 	"fmt"
-	"go/build"
-	"io"
 	"log"
 	"os"
-	"os/exec"
-	"path"
 	"path/filepath"
-	"regexp"
 	"runtime"
 	"strings"
-	"sync"
-	"text/template"
-	"unicode"
-	"unicode/utf8"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/bug"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/clean"
+	"cmd/go/internal/doc"
+	"cmd/go/internal/envcmd"
+	"cmd/go/internal/fix"
+	"cmd/go/internal/fmtcmd"
+	"cmd/go/internal/generate"
+	"cmd/go/internal/get"
+	"cmd/go/internal/help"
+	"cmd/go/internal/list"
+	"cmd/go/internal/run"
+	"cmd/go/internal/test"
+	"cmd/go/internal/tool"
+	"cmd/go/internal/version"
+	"cmd/go/internal/vet"
+	"cmd/go/internal/work"
 )
 
-// A Command is an implementation of a go command
-// like go build or go fix.
-type Command struct {
-	// Run runs the command.
-	// The args are the arguments after the command name.
-	Run func(cmd *Command, args []string)
+func init() {
+	base.Commands = []*base.Command{
+		work.CmdBuild,
+		clean.CmdClean,
+		doc.CmdDoc,
+		envcmd.CmdEnv,
+		bug.CmdBug,
+		fix.CmdFix,
+		fmtcmd.CmdFmt,
+		generate.CmdGenerate,
+		get.CmdGet,
+		work.CmdInstall,
+		list.CmdList,
+		run.CmdRun,
+		test.CmdTest,
+		tool.CmdTool,
+		version.CmdVersion,
+		vet.CmdVet,
 
-	// UsageLine is the one-line usage message.
-	// The first word in the line is taken to be the command name.
-	UsageLine string
-
-	// Short is the short description shown in the 'go help' output.
-	Short string
-
-	// Long is the long message shown in the 'go help <this-command>' output.
-	Long string
-
-	// Flag is a set of flags specific to this command.
-	Flag flag.FlagSet
-
-	// CustomFlags indicates that the command will do its own
-	// flag parsing.
-	CustomFlags bool
-}
-
-// Name returns the command's name: the first word in the usage line.
-func (c *Command) Name() string {
-	name := c.UsageLine
-	i := strings.Index(name, " ")
-	if i >= 0 {
-		name = name[:i]
+		help.HelpC,
+		help.HelpBuildmode,
+		help.HelpFileType,
+		help.HelpGopath,
+		help.HelpEnvironment,
+		help.HelpImportPath,
+		help.HelpPackages,
+		test.HelpTestflag,
+		test.HelpTestfunc,
 	}
-	return name
 }
 
-func (c *Command) Usage() {
-	fmt.Fprintf(os.Stderr, "usage: %s\n\n", c.UsageLine)
-	fmt.Fprintf(os.Stderr, "%s\n", strings.TrimSpace(c.Long))
-	os.Exit(2)
-}
-
-// Runnable reports whether the command can be run; otherwise
-// it is a documentation pseudo-command such as importpath.
-func (c *Command) Runnable() bool {
-	return c.Run != nil
-}
-
-// Commands lists the available commands and help topics.
-// The order here is the order in which they are printed by 'go help'.
-var commands = []*Command{
-	cmdBuild,
-	cmdClean,
-	cmdDoc,
-	cmdEnv,
-	cmdBug,
-	cmdFix,
-	cmdFmt,
-	cmdGenerate,
-	cmdGet,
-	cmdInstall,
-	cmdList,
-	cmdRun,
-	cmdTest,
-	cmdTool,
-	cmdVersion,
-	cmdVet,
-
-	helpC,
-	helpBuildmode,
-	helpFileType,
-	helpGopath,
-	helpEnvironment,
-	helpImportPath,
-	helpPackages,
-	helpTestflag,
-	helpTestfunc,
-}
-
-var exitStatus = 0
-var exitMu sync.Mutex
-
-func setExitStatus(n int) {
-	exitMu.Lock()
-	if exitStatus < n {
-		exitStatus = n
-	}
-	exitMu.Unlock()
-}
-
-var origEnv []string
-var newEnv []envVar
-
 func main() {
 	_ = go11tag
-	flag.Usage = usage
+	flag.Usage = base.Usage
 	flag.Parse()
 	log.SetFlags(0)
 
 	args := flag.Args()
 	if len(args) < 1 {
-		usage()
+		base.Usage()
 	}
 
 	if args[0] == "help" {
-		help(args[1:])
+		help.Help(args[1:])
 		return
 	}
 
 	// Diagnose common mistake: GOPATH==GOROOT.
 	// This setting is equivalent to not setting GOPATH at all,
 	// which is not what most people want when they do it.
-	if gopath := buildContext.GOPATH; filepath.Clean(gopath) == filepath.Clean(runtime.GOROOT()) {
+	if gopath := cfg.BuildContext.GOPATH; filepath.Clean(gopath) == filepath.Clean(runtime.GOROOT()) {
 		fmt.Fprintf(os.Stderr, "warning: GOPATH set to GOROOT (%s) has no effect\n", gopath)
 	} else {
 		for _, p := range filepath.SplitList(gopath) {
@@ -154,14 +103,12 @@
 		}
 	}
 
-	if fi, err := os.Stat(goroot); err != nil || !fi.IsDir() {
-		// For gccgo this is fine, carry on.
-		// Note that this check is imperfect as we have not yet
-		// parsed the -compiler flag.
-		if runtime.Compiler != "gccgo" {
-			fmt.Fprintf(os.Stderr, "go: cannot find GOROOT directory: %v\n", goroot)
-			os.Exit(2)
-		}
+	// For gccgo this is fine, carry on.
+	// Note that this check is imperfect as we have not yet parsed
+	// the -compiler flag.
+	if fi, err := os.Stat(cfg.GOROOT); err != nil || !fi.IsDir() && runtime.Compiler != "gccgo" {
+		fmt.Fprintf(os.Stderr, "go: cannot find GOROOT directory: %v\n", cfg.GOROOT)
+		os.Exit(2)
 	}
 
 	// Set environment (GOOS, GOARCH, etc) explicitly.
@@ -169,15 +116,15 @@
 	// the same default computation of these as we do,
 	// but in practice there might be skew
 	// This makes sure we all agree.
-	origEnv = os.Environ()
-	newEnv = mkEnv()
-	for _, env := range newEnv {
-		if os.Getenv(env.name) != env.value {
-			os.Setenv(env.name, env.value)
+	cfg.OrigEnv = os.Environ()
+	cfg.CmdEnv = envcmd.MkEnv()
+	for _, env := range cfg.CmdEnv {
+		if os.Getenv(env.Name) != env.Value {
+			os.Setenv(env.Name, env.Value)
 		}
 	}
 
-	for _, cmd := range commands {
+	for _, cmd := range base.Commands {
 		if cmd.Name() == args[0] && cmd.Runnable() {
 			cmd.Flag.Usage = func() { cmd.Usage() }
 			if cmd.CustomFlags {
@@ -187,615 +134,25 @@
 				args = cmd.Flag.Args()
 			}
 			cmd.Run(cmd, args)
-			exit()
+			base.Exit()
 			return
 		}
 	}
 
 	fmt.Fprintf(os.Stderr, "go: unknown subcommand %q\nRun 'go help' for usage.\n", args[0])
-	setExitStatus(2)
-	exit()
+	base.SetExitStatus(2)
+	base.Exit()
 }
 
-var usageTemplate = `Go is a tool for managing Go source code.
-
-Usage:
-
-	go command [arguments]
-
-The commands are:
-{{range .}}{{if .Runnable}}
-	{{.Name | printf "%-11s"}} {{.Short}}{{end}}{{end}}
-
-Use "go help [command]" for more information about a command.
-
-Additional help topics:
-{{range .}}{{if not .Runnable}}
-	{{.Name | printf "%-11s"}} {{.Short}}{{end}}{{end}}
-
-Use "go help [topic]" for more information about that topic.
-
-`
-
-var helpTemplate = `{{if .Runnable}}usage: go {{.UsageLine}}
-
-{{end}}{{.Long | trim}}
-`
-
-var documentationTemplate = `{{range .}}{{if .Short}}{{.Short | capitalize}}
-
-{{end}}{{if .Runnable}}Usage:
-
-	go {{.UsageLine}}
-
-{{end}}{{.Long | trim}}
-
-
-{{end}}`
-
-// commentWriter writes a Go comment to the underlying io.Writer,
-// using line comment form (//).
-type commentWriter struct {
-	W            io.Writer
-	wroteSlashes bool // Wrote "//" at the beginning of the current line.
+func init() {
+	base.Usage = mainUsage
 }
 
-func (c *commentWriter) Write(p []byte) (int, error) {
-	var n int
-	for i, b := range p {
-		if !c.wroteSlashes {
-			s := "//"
-			if b != '\n' {
-				s = "// "
-			}
-			if _, err := io.WriteString(c.W, s); err != nil {
-				return n, err
-			}
-			c.wroteSlashes = true
-		}
-		n0, err := c.W.Write(p[i : i+1])
-		n += n0
-		if err != nil {
-			return n, err
-		}
-		if b == '\n' {
-			c.wroteSlashes = false
-		}
-	}
-	return len(p), nil
-}
-
-// An errWriter wraps a writer, recording whether a write error occurred.
-type errWriter struct {
-	w   io.Writer
-	err error
-}
-
-func (w *errWriter) Write(b []byte) (int, error) {
-	n, err := w.w.Write(b)
-	if err != nil {
-		w.err = err
-	}
-	return n, err
-}
-
-// tmpl executes the given template text on data, writing the result to w.
-func tmpl(w io.Writer, text string, data interface{}) {
-	t := template.New("top")
-	t.Funcs(template.FuncMap{"trim": strings.TrimSpace, "capitalize": capitalize})
-	template.Must(t.Parse(text))
-	ew := &errWriter{w: w}
-	err := t.Execute(ew, data)
-	if ew.err != nil {
-		// I/O error writing. Ignore write on closed pipe.
-		if strings.Contains(ew.err.Error(), "pipe") {
-			os.Exit(1)
-		}
-		fatalf("writing output: %v", ew.err)
-	}
-	if err != nil {
-		panic(err)
-	}
-}
-
-func capitalize(s string) string {
-	if s == "" {
-		return s
-	}
-	r, n := utf8.DecodeRuneInString(s)
-	return string(unicode.ToTitle(r)) + s[n:]
-}
-
-func printUsage(w io.Writer) {
-	bw := bufio.NewWriter(w)
-	tmpl(bw, usageTemplate, commands)
-	bw.Flush()
-}
-
-func usage() {
+func mainUsage() {
 	// special case "go test -h"
 	if len(os.Args) > 1 && os.Args[1] == "test" {
-		os.Stderr.WriteString(testUsage + "\n\n" +
-			strings.TrimSpace(testFlag1) + "\n\n\t" +
-			strings.TrimSpace(testFlag2) + "\n")
-		os.Exit(2)
+		test.Usage()
 	}
-	printUsage(os.Stderr)
+	help.PrintUsage(os.Stderr)
 	os.Exit(2)
 }
-
-// help implements the 'help' command.
-func help(args []string) {
-	if len(args) == 0 {
-		printUsage(os.Stdout)
-		// not exit 2: succeeded at 'go help'.
-		return
-	}
-	if len(args) != 1 {
-		fmt.Fprintf(os.Stderr, "usage: go help command\n\nToo many arguments given.\n")
-		os.Exit(2) // failed at 'go help'
-	}
-
-	arg := args[0]
-
-	// 'go help documentation' generates doc.go.
-	if arg == "documentation" {
-		fmt.Println("// Copyright 2011 The Go Authors. All rights reserved.")
-		fmt.Println("// Use of this source code is governed by a BSD-style")
-		fmt.Println("// license that can be found in the LICENSE file.")
-		fmt.Println()
-		fmt.Println("// DO NOT EDIT THIS FILE. GENERATED BY mkalldocs.sh.")
-		fmt.Println("// Edit the documentation in other files and rerun mkalldocs.sh to generate this one.")
-		fmt.Println()
-		buf := new(bytes.Buffer)
-		printUsage(buf)
-		usage := &Command{Long: buf.String()}
-		tmpl(&commentWriter{W: os.Stdout}, documentationTemplate, append([]*Command{usage}, commands...))
-		fmt.Println("package main")
-		return
-	}
-
-	for _, cmd := range commands {
-		if cmd.Name() == arg {
-			tmpl(os.Stdout, helpTemplate, cmd)
-			// not exit 2: succeeded at 'go help cmd'.
-			return
-		}
-	}
-
-	fmt.Fprintf(os.Stderr, "Unknown help topic %#q.  Run 'go help'.\n", arg)
-	os.Exit(2) // failed at 'go help cmd'
-}
-
-// importPathsNoDotExpansion returns the import paths to use for the given
-// command line, but it does no ... expansion.
-func importPathsNoDotExpansion(args []string) []string {
-	if len(args) == 0 {
-		return []string{"."}
-	}
-	var out []string
-	for _, a := range args {
-		// Arguments are supposed to be import paths, but
-		// as a courtesy to Windows developers, rewrite \ to /
-		// in command-line arguments. Handles .\... and so on.
-		if filepath.Separator == '\\' {
-			a = strings.Replace(a, `\`, `/`, -1)
-		}
-
-		// Put argument in canonical form, but preserve leading ./.
-		if strings.HasPrefix(a, "./") {
-			a = "./" + path.Clean(a)
-			if a == "./." {
-				a = "."
-			}
-		} else {
-			a = path.Clean(a)
-		}
-		if isMetaPackage(a) {
-			out = append(out, allPackages(a)...)
-			continue
-		}
-		out = append(out, a)
-	}
-	return out
-}
-
-// importPaths returns the import paths to use for the given command line.
-func importPaths(args []string) []string {
-	args = importPathsNoDotExpansion(args)
-	var out []string
-	for _, a := range args {
-		if strings.Contains(a, "...") {
-			if build.IsLocalImport(a) {
-				out = append(out, allPackagesInFS(a)...)
-			} else {
-				out = append(out, allPackages(a)...)
-			}
-			continue
-		}
-		out = append(out, a)
-	}
-	return out
-}
-
-var atexitFuncs []func()
-
-func atexit(f func()) {
-	atexitFuncs = append(atexitFuncs, f)
-}
-
-func exit() {
-	for _, f := range atexitFuncs {
-		f()
-	}
-	os.Exit(exitStatus)
-}
-
-func fatalf(format string, args ...interface{}) {
-	errorf(format, args...)
-	exit()
-}
-
-func errorf(format string, args ...interface{}) {
-	log.Printf(format, args...)
-	setExitStatus(1)
-}
-
-func exitIfErrors() {
-	if exitStatus != 0 {
-		exit()
-	}
-}
-
-func run(cmdargs ...interface{}) {
-	cmdline := stringList(cmdargs...)
-	if buildN || buildX {
-		fmt.Printf("%s\n", strings.Join(cmdline, " "))
-		if buildN {
-			return
-		}
-	}
-
-	cmd := exec.Command(cmdline[0], cmdline[1:]...)
-	cmd.Stdout = os.Stdout
-	cmd.Stderr = os.Stderr
-	if err := cmd.Run(); err != nil {
-		errorf("%v", err)
-	}
-}
-
-// envForDir returns a copy of the environment
-// suitable for running in the given directory.
-// The environment is the current process's environment
-// but with an updated $PWD, so that an os.Getwd in the
-// child will be faster.
-func envForDir(dir string, base []string) []string {
-	// Internally we only use rooted paths, so dir is rooted.
-	// Even if dir is not rooted, no harm done.
-	return mergeEnvLists([]string{"PWD=" + dir}, base)
-}
-
-// mergeEnvLists merges the two environment lists such that
-// variables with the same name in "in" replace those in "out".
-// This always returns a newly allocated slice.
-func mergeEnvLists(in, out []string) []string {
-	out = append([]string(nil), out...)
-NextVar:
-	for _, inkv := range in {
-		k := strings.SplitAfterN(inkv, "=", 2)[0]
-		for i, outkv := range out {
-			if strings.HasPrefix(outkv, k) {
-				out[i] = inkv
-				continue NextVar
-			}
-		}
-		out = append(out, inkv)
-	}
-	return out
-}
-
-// matchPattern(pattern)(name) reports whether
-// name matches pattern. Pattern is a limited glob
-// pattern in which '...' means 'any string' and there
-// is no other special syntax.
-func matchPattern(pattern string) func(name string) bool {
-	re := regexp.QuoteMeta(pattern)
-	re = strings.Replace(re, `\.\.\.`, `.*`, -1)
-	// Special case: foo/... matches foo too.
-	if strings.HasSuffix(re, `/.*`) {
-		re = re[:len(re)-len(`/.*`)] + `(/.*)?`
-	}
-	reg := regexp.MustCompile(`^` + re + `$`)
-	return func(name string) bool {
-		return reg.MatchString(name)
-	}
-}
-
-// hasPathPrefix reports whether the path s begins with the
-// elements in prefix.
-func hasPathPrefix(s, prefix string) bool {
-	switch {
-	default:
-		return false
-	case len(s) == len(prefix):
-		return s == prefix
-	case len(s) > len(prefix):
-		if prefix != "" && prefix[len(prefix)-1] == '/' {
-			return strings.HasPrefix(s, prefix)
-		}
-		return s[len(prefix)] == '/' && s[:len(prefix)] == prefix
-	}
-}
-
-// hasFilePathPrefix reports whether the filesystem path s begins with the
-// elements in prefix.
-func hasFilePathPrefix(s, prefix string) bool {
-	sv := strings.ToUpper(filepath.VolumeName(s))
-	pv := strings.ToUpper(filepath.VolumeName(prefix))
-	s = s[len(sv):]
-	prefix = prefix[len(pv):]
-	switch {
-	default:
-		return false
-	case sv != pv:
-		return false
-	case len(s) == len(prefix):
-		return s == prefix
-	case len(s) > len(prefix):
-		if prefix != "" && prefix[len(prefix)-1] == filepath.Separator {
-			return strings.HasPrefix(s, prefix)
-		}
-		return s[len(prefix)] == filepath.Separator && s[:len(prefix)] == prefix
-	}
-}
-
-// expandPath returns the symlink-expanded form of path.
-func expandPath(p string) string {
-	x, err := filepath.EvalSymlinks(p)
-	if err == nil {
-		return x
-	}
-	return p
-}
-
-// treeCanMatchPattern(pattern)(name) reports whether
-// name or children of name can possibly match pattern.
-// Pattern is the same limited glob accepted by matchPattern.
-func treeCanMatchPattern(pattern string) func(name string) bool {
-	wildCard := false
-	if i := strings.Index(pattern, "..."); i >= 0 {
-		wildCard = true
-		pattern = pattern[:i]
-	}
-	return func(name string) bool {
-		return len(name) <= len(pattern) && hasPathPrefix(pattern, name) ||
-			wildCard && strings.HasPrefix(name, pattern)
-	}
-}
-
-// allPackages returns all the packages that can be found
-// under the $GOPATH directories and $GOROOT matching pattern.
-// The pattern is either "all" (all packages), "std" (standard packages),
-// "cmd" (standard commands), or a path including "...".
-func allPackages(pattern string) []string {
-	pkgs := matchPackages(pattern)
-	if len(pkgs) == 0 {
-		fmt.Fprintf(os.Stderr, "warning: %q matched no packages\n", pattern)
-	}
-	return pkgs
-}
-
-func matchPackages(pattern string) []string {
-	match := func(string) bool { return true }
-	treeCanMatch := func(string) bool { return true }
-	if !isMetaPackage(pattern) {
-		match = matchPattern(pattern)
-		treeCanMatch = treeCanMatchPattern(pattern)
-	}
-
-	have := map[string]bool{
-		"builtin": true, // ignore pseudo-package that exists only for documentation
-	}
-	if !buildContext.CgoEnabled {
-		have["runtime/cgo"] = true // ignore during walk
-	}
-	var pkgs []string
-
-	for _, src := range buildContext.SrcDirs() {
-		if (pattern == "std" || pattern == "cmd") && src != gorootSrc {
-			continue
-		}
-		src = filepath.Clean(src) + string(filepath.Separator)
-		root := src
-		if pattern == "cmd" {
-			root += "cmd" + string(filepath.Separator)
-		}
-		filepath.Walk(root, func(path string, fi os.FileInfo, err error) error {
-			if err != nil || !fi.IsDir() || path == src {
-				return nil
-			}
-
-			// Avoid .foo, _foo, and testdata directory trees.
-			_, elem := filepath.Split(path)
-			if strings.HasPrefix(elem, ".") || strings.HasPrefix(elem, "_") || elem == "testdata" {
-				return filepath.SkipDir
-			}
-
-			name := filepath.ToSlash(path[len(src):])
-			if pattern == "std" && (!isStandardImportPath(name) || name == "cmd") {
-				// The name "std" is only the standard library.
-				// If the name is cmd, it's the root of the command tree.
-				return filepath.SkipDir
-			}
-			if !treeCanMatch(name) {
-				return filepath.SkipDir
-			}
-			if have[name] {
-				return nil
-			}
-			have[name] = true
-			if !match(name) {
-				return nil
-			}
-			_, err = buildContext.ImportDir(path, 0)
-			if err != nil {
-				if _, noGo := err.(*build.NoGoError); noGo {
-					return nil
-				}
-			}
-			pkgs = append(pkgs, name)
-			return nil
-		})
-	}
-	return pkgs
-}
-
-// allPackagesInFS is like allPackages but is passed a pattern
-// beginning ./ or ../, meaning it should scan the tree rooted
-// at the given directory. There are ... in the pattern too.
-func allPackagesInFS(pattern string) []string {
-	pkgs := matchPackagesInFS(pattern)
-	if len(pkgs) == 0 {
-		fmt.Fprintf(os.Stderr, "warning: %q matched no packages\n", pattern)
-	}
-	return pkgs
-}
-
-func matchPackagesInFS(pattern string) []string {
-	// Find directory to begin the scan.
-	// Could be smarter but this one optimization
-	// is enough for now, since ... is usually at the
-	// end of a path.
-	i := strings.Index(pattern, "...")
-	dir, _ := path.Split(pattern[:i])
-
-	// pattern begins with ./ or ../.
-	// path.Clean will discard the ./ but not the ../.
-	// We need to preserve the ./ for pattern matching
-	// and in the returned import paths.
-	prefix := ""
-	if strings.HasPrefix(pattern, "./") {
-		prefix = "./"
-	}
-	match := matchPattern(pattern)
-
-	var pkgs []string
-	filepath.Walk(dir, func(path string, fi os.FileInfo, err error) error {
-		if err != nil || !fi.IsDir() {
-			return nil
-		}
-		if path == dir {
-			// filepath.Walk starts at dir and recurses. For the recursive case,
-			// the path is the result of filepath.Join, which calls filepath.Clean.
-			// The initial case is not Cleaned, though, so we do this explicitly.
-			//
-			// This converts a path like "./io/" to "io". Without this step, running
-			// "cd $GOROOT/src; go list ./io/..." would incorrectly skip the io
-			// package, because prepending the prefix "./" to the unclean path would
-			// result in "././io", and match("././io") returns false.
-			path = filepath.Clean(path)
-		}
-
-		// Avoid .foo, _foo, and testdata directory trees, but do not avoid "." or "..".
-		_, elem := filepath.Split(path)
-		dot := strings.HasPrefix(elem, ".") && elem != "." && elem != ".."
-		if dot || strings.HasPrefix(elem, "_") || elem == "testdata" {
-			return filepath.SkipDir
-		}
-
-		name := prefix + filepath.ToSlash(path)
-		if !match(name) {
-			return nil
-		}
-
-		// We keep the directory if we can import it, or if we can't import it
-		// due to invalid Go source files. This means that directories containing
-		// parse errors will be built (and fail) instead of being silently skipped
-		// as not matching the pattern. Go 1.5 and earlier skipped, but that
-		// behavior means people miss serious mistakes.
-		// See golang.org/issue/11407.
-		if p, err := buildContext.ImportDir(path, 0); err != nil && (p == nil || len(p.InvalidGoFiles) == 0) {
-			if _, noGo := err.(*build.NoGoError); !noGo {
-				log.Print(err)
-			}
-			return nil
-		}
-		pkgs = append(pkgs, name)
-		return nil
-	})
-	return pkgs
-}
-
-// stringList's arguments should be a sequence of string or []string values.
-// stringList flattens them into a single []string.
-func stringList(args ...interface{}) []string {
-	var x []string
-	for _, arg := range args {
-		switch arg := arg.(type) {
-		case []string:
-			x = append(x, arg...)
-		case string:
-			x = append(x, arg)
-		default:
-			panic("stringList: invalid argument of type " + fmt.Sprintf("%T", arg))
-		}
-	}
-	return x
-}
-
-// toFold returns a string with the property that
-//	strings.EqualFold(s, t) iff toFold(s) == toFold(t)
-// This lets us test a large set of strings for fold-equivalent
-// duplicates without making a quadratic number of calls
-// to EqualFold. Note that strings.ToUpper and strings.ToLower
-// have the desired property in some corner cases.
-func toFold(s string) string {
-	// Fast path: all ASCII, no upper case.
-	// Most paths look like this already.
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if c >= utf8.RuneSelf || 'A' <= c && c <= 'Z' {
-			goto Slow
-		}
-	}
-	return s
-
-Slow:
-	var buf bytes.Buffer
-	for _, r := range s {
-		// SimpleFold(x) cycles to the next equivalent rune > x
-		// or wraps around to smaller values. Iterate until it wraps,
-		// and we've found the minimum value.
-		for {
-			r0 := r
-			r = unicode.SimpleFold(r0)
-			if r <= r0 {
-				break
-			}
-		}
-		// Exception to allow fast path above: A-Z => a-z
-		if 'A' <= r && r <= 'Z' {
-			r += 'a' - 'A'
-		}
-		buf.WriteRune(r)
-	}
-	return buf.String()
-}
-
-// foldDup reports a pair of strings from the list that are
-// equal according to strings.EqualFold.
-// It returns "", "" if there are no such strings.
-func foldDup(list []string) (string, string) {
-	clash := map[string]string{}
-	for _, s := range list {
-		fold := toFold(s)
-		if t := clash[fold]; t != "" {
-			if s > t {
-				s, t = t, s
-			}
-			return s, t
-		}
-		clash[fold] = s
-	}
-	return "", ""
-}
diff --git a/libgo/go/cmd/go/match_test.go b/libgo/go/cmd/go/match_test.go
deleted file mode 100644
index e0ad562..0000000
--- a/libgo/go/cmd/go/match_test.go
+++ /dev/null
@@ -1,88 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import "testing"
-
-var matchPatternTests = []stringPairTest{
-	{"...", "foo", true},
-	{"net", "net", true},
-	{"net", "net/http", false},
-	{"net/http", "net", false},
-	{"net/http", "net/http", true},
-	{"net...", "netchan", true},
-	{"net...", "net", true},
-	{"net...", "net/http", true},
-	{"net...", "not/http", false},
-	{"net/...", "netchan", false},
-	{"net/...", "net", true},
-	{"net/...", "net/http", true},
-	{"net/...", "not/http", false},
-}
-
-func TestMatchPattern(t *testing.T) {
-	testStringPairs(t, "matchPattern", matchPatternTests, func(pattern, name string) bool {
-		return matchPattern(pattern)(name)
-	})
-}
-
-var treeCanMatchPatternTests = []stringPairTest{
-	{"...", "foo", true},
-	{"net", "net", true},
-	{"net", "net/http", false},
-	{"net/http", "net", true},
-	{"net/http", "net/http", true},
-	{"net...", "netchan", true},
-	{"net...", "net", true},
-	{"net...", "net/http", true},
-	{"net...", "not/http", false},
-	{"net/...", "netchan", false},
-	{"net/...", "net", true},
-	{"net/...", "net/http", true},
-	{"net/...", "not/http", false},
-	{"abc.../def", "abcxyz", true},
-	{"abc.../def", "xyxabc", false},
-	{"x/y/z/...", "x", true},
-	{"x/y/z/...", "x/y", true},
-	{"x/y/z/...", "x/y/z", true},
-	{"x/y/z/...", "x/y/z/w", true},
-	{"x/y/z", "x", true},
-	{"x/y/z", "x/y", true},
-	{"x/y/z", "x/y/z", true},
-	{"x/y/z", "x/y/z/w", false},
-	{"x/.../y/z", "x/a/b/c", true},
-	{"x/.../y/z", "y/x/a/b/c", false},
-}
-
-func TestChildrenCanMatchPattern(t *testing.T) {
-	testStringPairs(t, "treeCanMatchPattern", treeCanMatchPatternTests, func(pattern, name string) bool {
-		return treeCanMatchPattern(pattern)(name)
-	})
-}
-
-var hasPathPrefixTests = []stringPairTest{
-	{"abc", "a", false},
-	{"a/bc", "a", true},
-	{"a", "a", true},
-	{"a/bc", "a/", true},
-}
-
-func TestHasPathPrefix(t *testing.T) {
-	testStringPairs(t, "hasPathPrefix", hasPathPrefixTests, hasPathPrefix)
-}
-
-type stringPairTest struct {
-	in1 string
-	in2 string
-	out bool
-}
-
-func testStringPairs(t *testing.T, name string, tests []stringPairTest, f func(string, string) bool) {
-	for _, tt := range tests {
-		if out := f(tt.in1, tt.in2); out != tt.out {
-			t.Errorf("%s(%q, %q) = %v, want %v", name, tt.in1, tt.in2, out, tt.out)
-		}
-	}
-}
diff --git a/libgo/go/cmd/go/note_test.go b/libgo/go/cmd/go/note_test.go
index 7b5568f..f33efdc 100644
--- a/libgo/go/cmd/go/note_test.go
+++ b/libgo/go/cmd/go/note_test.go
@@ -7,10 +7,11 @@
 package main_test
 
 import (
-	main "cmd/go"
 	"go/build"
 	"runtime"
 	"testing"
+
+	"cmd/go/internal/buildid"
 )
 
 func TestNoteReading(t *testing.T) {
@@ -23,9 +24,9 @@
 	}
 	// Set BuildIDReadSize to 2kB to exercise Mach-O parsing more strictly.
 	defer func(old int) {
-		main.BuildIDReadSize = old
-	}(main.BuildIDReadSize)
-	main.BuildIDReadSize = 2 * 1024
+		buildid.BuildIDReadSize = old
+	}(buildid.BuildIDReadSize)
+	buildid.BuildIDReadSize = 2 * 1024
 
 	testNoteReading(t)
 }
@@ -36,7 +37,7 @@
 	tg.tempFile("hello.go", `package main; func main() { print("hello, world\n") }`)
 	const buildID = "TestNoteReading-Build-ID"
 	tg.run("build", "-ldflags", "-buildid="+buildID, "-o", tg.path("hello.exe"), tg.path("hello.go"))
-	id, err := main.ReadBuildIDFromBinary(tg.path("hello.exe"))
+	id, err := buildid.ReadBuildIDFromBinary(tg.path("hello.exe"))
 	if err != nil {
 		t.Fatalf("reading build ID from hello binary: %v", err)
 	}
@@ -56,7 +57,7 @@
 	}
 
 	tg.run("build", "-ldflags", "-buildid="+buildID+" -linkmode=external", "-o", tg.path("hello.exe"), tg.path("hello.go"))
-	id, err = main.ReadBuildIDFromBinary(tg.path("hello.exe"))
+	id, err = buildid.ReadBuildIDFromBinary(tg.path("hello.exe"))
 	if err != nil {
 		t.Fatalf("reading build ID from hello binary (linkmode=external): %v", err)
 	}
diff --git a/libgo/go/cmd/go/pkg_test.go b/libgo/go/cmd/go/pkg_test.go
deleted file mode 100644
index fba1363..0000000
--- a/libgo/go/cmd/go/pkg_test.go
+++ /dev/null
@@ -1,194 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
-	"io/ioutil"
-	"os"
-	"path/filepath"
-	"reflect"
-	"strings"
-	"testing"
-)
-
-var foldDupTests = []struct {
-	list   []string
-	f1, f2 string
-}{
-	{stringList("math/rand", "math/big"), "", ""},
-	{stringList("math", "strings"), "", ""},
-	{stringList("strings"), "", ""},
-	{stringList("strings", "strings"), "strings", "strings"},
-	{stringList("Rand", "rand", "math", "math/rand", "math/Rand"), "Rand", "rand"},
-}
-
-func TestFoldDup(t *testing.T) {
-	for _, tt := range foldDupTests {
-		f1, f2 := foldDup(tt.list)
-		if f1 != tt.f1 || f2 != tt.f2 {
-			t.Errorf("foldDup(%q) = %q, %q, want %q, %q", tt.list, f1, f2, tt.f1, tt.f2)
-		}
-	}
-}
-
-var parseMetaGoImportsTests = []struct {
-	in  string
-	out []metaImport
-}{
-	{
-		`<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">`,
-		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
-	},
-	{
-		`<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">
-		<meta name="go-import" content="baz/quux git http://github.com/rsc/baz/quux">`,
-		[]metaImport{
-			{"foo/bar", "git", "https://github.com/rsc/foo/bar"},
-			{"baz/quux", "git", "http://github.com/rsc/baz/quux"},
-		},
-	},
-	{
-		`<head>
-		<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">
-		</head>`,
-		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
-	},
-	{
-		`<meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">
-		<body>`,
-		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
-	},
-	{
-		`<!doctype html><meta name="go-import" content="foo/bar git https://github.com/rsc/foo/bar">`,
-		[]metaImport{{"foo/bar", "git", "https://github.com/rsc/foo/bar"}},
-	},
-	{
-		// XML doesn't like <div style=position:relative>.
-		`<!doctype html><title>Page Not Found</title><meta name=go-import content="chitin.io/chitin git https://github.com/chitin-io/chitin"><div style=position:relative>DRAFT</div>`,
-		[]metaImport{{"chitin.io/chitin", "git", "https://github.com/chitin-io/chitin"}},
-	},
-}
-
-func TestParseMetaGoImports(t *testing.T) {
-	for i, tt := range parseMetaGoImportsTests {
-		out, err := parseMetaGoImports(strings.NewReader(tt.in))
-		if err != nil {
-			t.Errorf("test#%d: %v", i, err)
-			continue
-		}
-		if !reflect.DeepEqual(out, tt.out) {
-			t.Errorf("test#%d:\n\thave %q\n\twant %q", i, out, tt.out)
-		}
-	}
-}
-
-func TestSharedLibName(t *testing.T) {
-	// TODO(avdva) - make these values platform-specific
-	prefix := "lib"
-	suffix := ".so"
-	testData := []struct {
-		args      []string
-		pkgs      []*Package
-		expected  string
-		expectErr bool
-		rootedAt  string
-	}{
-		{
-			args:     []string{"std"},
-			pkgs:     []*Package{},
-			expected: "std",
-		},
-		{
-			args:     []string{"std", "cmd"},
-			pkgs:     []*Package{},
-			expected: "std,cmd",
-		},
-		{
-			args:     []string{},
-			pkgs:     []*Package{&Package{ImportPath: "gopkg.in/somelib"}},
-			expected: "gopkg.in-somelib",
-		},
-		{
-			args:     []string{"./..."},
-			pkgs:     []*Package{&Package{ImportPath: "somelib"}},
-			expected: "somelib",
-			rootedAt: "somelib",
-		},
-		{
-			args:     []string{"../somelib", "../somelib"},
-			pkgs:     []*Package{&Package{ImportPath: "somelib"}},
-			expected: "somelib",
-		},
-		{
-			args:     []string{"../lib1", "../lib2"},
-			pkgs:     []*Package{&Package{ImportPath: "gopkg.in/lib1"}, &Package{ImportPath: "gopkg.in/lib2"}},
-			expected: "gopkg.in-lib1,gopkg.in-lib2",
-		},
-		{
-			args: []string{"./..."},
-			pkgs: []*Package{
-				&Package{ImportPath: "gopkg.in/dir/lib1"},
-				&Package{ImportPath: "gopkg.in/lib2"},
-				&Package{ImportPath: "gopkg.in/lib3"},
-			},
-			expected: "gopkg.in",
-			rootedAt: "gopkg.in",
-		},
-		{
-			args:      []string{"std", "../lib2"},
-			pkgs:      []*Package{},
-			expectErr: true,
-		},
-		{
-			args:      []string{"all", "./"},
-			pkgs:      []*Package{},
-			expectErr: true,
-		},
-		{
-			args:      []string{"cmd", "fmt"},
-			pkgs:      []*Package{},
-			expectErr: true,
-		},
-	}
-	for _, data := range testData {
-		func() {
-			if data.rootedAt != "" {
-				tmpGopath, err := ioutil.TempDir("", "gopath")
-				if err != nil {
-					t.Fatal(err)
-				}
-				oldGopath := buildContext.GOPATH
-				defer func() {
-					buildContext.GOPATH = oldGopath
-					os.Chdir(cwd)
-					err := os.RemoveAll(tmpGopath)
-					if err != nil {
-						t.Error(err)
-					}
-				}()
-				root := filepath.Join(tmpGopath, "src", data.rootedAt)
-				err = os.MkdirAll(root, 0755)
-				if err != nil {
-					t.Fatal(err)
-				}
-				buildContext.GOPATH = tmpGopath
-				os.Chdir(root)
-			}
-			computed, err := libname(data.args, data.pkgs)
-			if err != nil {
-				if !data.expectErr {
-					t.Errorf("libname returned an error %q, expected a name", err.Error())
-				}
-			} else if data.expectErr {
-				t.Errorf("libname returned %q, expected an error", computed)
-			} else {
-				expected := prefix + data.expected + suffix
-				if expected != computed {
-					t.Errorf("libname returned %q, expected %q", computed, expected)
-				}
-			}
-		}()
-	}
-}
diff --git a/libgo/go/cmd/go/run.go b/libgo/go/cmd/go/run.go
deleted file mode 100644
index 18387b5..0000000
--- a/libgo/go/cmd/go/run.go
+++ /dev/null
@@ -1,156 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
-	"fmt"
-	"os"
-	"os/exec"
-	"runtime"
-	"strings"
-)
-
-var execCmd []string // -exec flag, for run and test
-
-func findExecCmd() []string {
-	if execCmd != nil {
-		return execCmd
-	}
-	execCmd = []string{} // avoid work the second time
-	if goos == runtime.GOOS && goarch == runtime.GOARCH {
-		return execCmd
-	}
-	path, err := exec.LookPath(fmt.Sprintf("go_%s_%s_exec", goos, goarch))
-	if err == nil {
-		execCmd = []string{path}
-	}
-	return execCmd
-}
-
-var cmdRun = &Command{
-	UsageLine: "run [build flags] [-exec xprog] gofiles... [arguments...]",
-	Short:     "compile and run Go program",
-	Long: `
-Run compiles and runs the main package comprising the named Go source files.
-A Go source file is defined to be a file ending in a literal ".go" suffix.
-
-By default, 'go run' runs the compiled binary directly: 'a.out arguments...'.
-If the -exec flag is given, 'go run' invokes the binary using xprog:
-	'xprog a.out arguments...'.
-If the -exec flag is not given, GOOS or GOARCH is different from the system
-default, and a program named go_$GOOS_$GOARCH_exec can be found
-on the current search path, 'go run' invokes the binary using that program,
-for example 'go_nacl_386_exec a.out arguments...'. This allows execution of
-cross-compiled programs when a simulator or other execution method is
-available.
-
-For more about build flags, see 'go help build'.
-
-See also: go build.
-	`,
-}
-
-func init() {
-	cmdRun.Run = runRun // break init loop
-
-	addBuildFlags(cmdRun)
-	cmdRun.Flag.Var((*stringsFlag)(&execCmd), "exec", "")
-}
-
-func printStderr(args ...interface{}) (int, error) {
-	return fmt.Fprint(os.Stderr, args...)
-}
-
-func runRun(cmd *Command, args []string) {
-	instrumentInit()
-	buildModeInit()
-	var b builder
-	b.init()
-	b.print = printStderr
-	i := 0
-	for i < len(args) && strings.HasSuffix(args[i], ".go") {
-		i++
-	}
-	files, cmdArgs := args[:i], args[i:]
-	if len(files) == 0 {
-		fatalf("go run: no go files listed")
-	}
-	for _, file := range files {
-		if strings.HasSuffix(file, "_test.go") {
-			// goFilesPackage is going to assign this to TestGoFiles.
-			// Reject since it won't be part of the build.
-			fatalf("go run: cannot run *_test.go files (%s)", file)
-		}
-	}
-	p := goFilesPackage(files)
-	if p.Error != nil {
-		fatalf("%s", p.Error)
-	}
-	p.omitDWARF = true
-	if len(p.DepsErrors) > 0 {
-		// Since these are errors in dependencies,
-		// the same error might show up multiple times,
-		// once in each package that depends on it.
-		// Only print each once.
-		printed := map[*PackageError]bool{}
-		for _, err := range p.DepsErrors {
-			if !printed[err] {
-				printed[err] = true
-				errorf("%s", err)
-			}
-		}
-	}
-	exitIfErrors()
-	if p.Name != "main" {
-		fatalf("go run: cannot run non-main package")
-	}
-	p.target = "" // must build - not up to date
-	var src string
-	if len(p.GoFiles) > 0 {
-		src = p.GoFiles[0]
-	} else if len(p.CgoFiles) > 0 {
-		src = p.CgoFiles[0]
-	} else {
-		// this case could only happen if the provided source uses cgo
-		// while cgo is disabled.
-		hint := ""
-		if !buildContext.CgoEnabled {
-			hint = " (cgo is disabled)"
-		}
-		fatalf("go run: no suitable source files%s", hint)
-	}
-	p.exeName = src[:len(src)-len(".go")] // name temporary executable for first go file
-	a1 := b.action(modeBuild, modeBuild, p)
-	a := &action{f: (*builder).runProgram, args: cmdArgs, deps: []*action{a1}}
-	b.do(a)
-}
-
-// runProgram is the action for running a binary that has already
-// been compiled. We ignore exit status.
-func (b *builder) runProgram(a *action) error {
-	cmdline := stringList(findExecCmd(), a.deps[0].target, a.args)
-	if buildN || buildX {
-		b.showcmd("", "%s", strings.Join(cmdline, " "))
-		if buildN {
-			return nil
-		}
-	}
-
-	runStdin(cmdline)
-	return nil
-}
-
-// runStdin is like run, but connects Stdin.
-func runStdin(cmdline []string) {
-	cmd := exec.Command(cmdline[0], cmdline[1:]...)
-	cmd.Stdin = os.Stdin
-	cmd.Stdout = os.Stdout
-	cmd.Stderr = os.Stderr
-	cmd.Env = origEnv
-	startSigHandlers()
-	if err := cmd.Run(); err != nil {
-		errorf("%v", err)
-	}
-}
diff --git a/libgo/go/cmd/go/script b/libgo/go/cmd/go/script
deleted file mode 100755
index 340a7e8..0000000
--- a/libgo/go/cmd/go/script
+++ /dev/null
@@ -1,23 +0,0 @@
-#!/bin/sh
-
-x() {
-	echo '--- ' "$@"
-	"$@"
-	echo '---'
-	echo
-}
-
-x go help
-x go help build
-x go help clean
-x go help install
-x go help fix
-x go help fmt
-x go help get
-x go help list
-x go help test
-x go help version
-x go help vet
-x go help gopath
-x go help importpath
-x go help remote
diff --git a/libgo/go/cmd/go/script.txt b/libgo/go/cmd/go/script.txt
deleted file mode 100644
index a672146..0000000
--- a/libgo/go/cmd/go/script.txt
+++ /dev/null
@@ -1,352 +0,0 @@
----  go help
-usage: go command [arguments]
-
-go manages Go source code.
-
-The commands are:
-
-    build       compile and install packages and dependencies
-    clean       remove intermediate objects
-    fix         run gofix on packages
-    fmt         run gofmt -w on packages
-    get         download and install packages and dependencies
-    install     install packages and dependencies
-    list        list packages
-    test        test packages
-    version     print Go version
-    vet         run govet on packages
-
-Use "go help [command]" for more information about a command.
-
-Additional help topics:
-
-    gopath      GOPATH environment variable
-    importpath  description of import paths
-    remote      remote import path syntax
-
-Use "go help [topic]" for more information about that topic.
-
----
-
----  go help build
-usage: go build [-n] [-v] [importpath...]
-
-Build compiles the packages named by the import paths,
-along with their dependencies, but it does not install the results.
-
-The -n flag prints the commands but does not run them.
-The -v flag prints the commands.
-
-For more about import paths, see 'go help importpath'.
-
-See also: go install, go get, go clean.
----
-
----  go help clean
-usage: go clean [-nuke] [importpath...]
-
-Clean removes intermediate object files generated during
-the compilation of the packages named by the import paths,
-but by default it does not remove the installed package binaries.
-
-The -nuke flag causes clean to remove the installed package binaries too.
-
-TODO: Clean does not clean dependencies of the packages.
-
-For more about import paths, see 'go help importpath'.
----
-
----  go help install
-usage: go install [-n] [-v] [importpath...]
-
-Install compiles and installs the packages named by the import paths,
-along with their dependencies.
-
-The -n flag prints the commands but does not run them.
-The -v flag prints the commands.
-
-For more about import paths, see 'go help importpath'.
-
-See also: go build, go get, go clean.
----
-
----  go help fix
-usage: go fix [importpath...]
-
-Fix runs the gofix command on the packages named by the import paths.
-
-For more about gofix, see 'godoc gofix'.
-For more about import paths, see 'go help importpath'.
-
-To run gofix with specific options, run gofix itself.
-
-See also: go fmt, go vet.
----
-
----  go help fmt
-usage: go fmt [importpath...]
-
-Fmt runs the command 'gofmt -w' on the packages named by the import paths.
-
-For more about gofmt, see 'godoc gofmt'.
-For more about import paths, see 'go help importpath'.
-
-To run gofmt with specific options, run gofmt itself.
-
-See also: go fix, go vet.
----
-
----  go help get
-usage: go get [importpath...]
-
-Get downloads and installs the packages named by the import paths,
-along with their dependencies.
-
-After downloading the code, 'go get' looks for a tag beginning
-with "go." that corresponds to the local Go version.
-For Go "release.r58" it looks for a tag named "go.r58".
-For "weekly.2011-06-03" it looks for "go.weekly.2011-06-03".
-If the specific "go.X" tag is not found, it uses the latest earlier
-version it can find.  Otherwise, it uses the default version for
-the version control system: HEAD for git, tip for Mercurial,
-and so on.
-
-TODO: Explain versions better.
-
-For more about import paths, see 'go help importpath'.
-
-For more about how 'go get' finds source code to
-download, see 'go help remote'.
-
-See also: go build, go install, go clean.
----
-
----  go help list
-usage: go list [-f format] [-json] [importpath...]
-
-List lists the packages named by the import paths.
-
-The default output shows the package name and file system location:
-
-    books /home/you/src/google-api-go-client.googlecode.com/hg/books/v1
-    oauth /home/you/src/goauth2.googlecode.com/hg/oauth
-    sqlite /home/you/src/gosqlite.googlecode.com/hg/sqlite
-
-The -f flag specifies an alternate format for the list,
-using the syntax of package template.  The default output
-is equivalent to -f '{{.Name}} {{.Dir}}'  The struct
-being passed to the template is:
-
-    type Package struct {
-        Name string         // package name
-        Doc string          // package documentation string
-        GoFiles []string    // names of Go source files in package
-        ImportPath string   // import path denoting package
-        Imports []string    // import paths used by this package
-        Deps []string       // all (recursively) imported dependencies
-        Dir string          // directory containing package sources
-        Version string      // version of installed package
-    }
-
-The -json flag causes the package data to be printed in JSON format.
-
-For more about import paths, see 'go help importpath'.
----
-
----  go help test
-usage: go test [importpath...]
-
-Test runs gotest to test the packages named by the import paths.
-It prints a summary of the test results in the format:
-
-	test archive/tar
-	FAIL archive/zip
-	test compress/gzip
-	...
-
-followed by gotest output for each failed package.
-
-For more about import paths, see 'go help importpath'.
-
-See also: go build, go compile, go vet.
----
-
----  go help version
-usage: go version
-
-Version prints the Go version, as reported by runtime.Version.
----
-
----  go help vet
-usage: go vet [importpath...]
-
-Vet runs the govet command on the packages named by the import paths.
-
-For more about govet, see 'godoc govet'.
-For more about import paths, see 'go help importpath'.
-
-To run govet with specific options, run govet itself.
-
-See also: go fmt, go fix.
----
-
----  go help gopath
-The GOPATH environment variable lists places to look for Go code.
-On Unix, the value is a colon-separated string.
-On Windows, the value is a semicolon-separated string.
-On Plan 9, the value is a list.
-
-GOPATH must be set to build and install packages outside the
-standard Go tree.
-
-Each directory listed in GOPATH must have a prescribed structure:
-
-The src/ directory holds source code.  The path below 'src'
-determines the import path or executable name.
-
-The pkg/ directory holds installed package objects.
-As in the Go tree, each target operating system and
-architecture pair has its own subdirectory of pkg
-(pkg/GOOS_GOARCH).
-
-If DIR is a directory listed in the GOPATH, a package with
-source in DIR/src/foo/bar can be imported as "foo/bar" and
-has its compiled form installed to "DIR/pkg/GOOS_GOARCH/foo/bar.a".
-
-The bin/ directory holds compiled commands.
-Each command is named for its source directory, but only
-the final element, not the entire path.  That is, the
-command with source in DIR/src/foo/quux is installed into
-DIR/bin/quux, not DIR/bin/foo/quux.  The foo/ is stripped
-so that you can add DIR/bin to your PATH to get at the
-installed commands.
-
-Here's an example directory layout:
-
-    GOPATH=/home/user/gocode
-
-    /home/user/gocode/
-        src/
-            foo/
-                bar/               (go code in package bar)
-                    x.go
-                quux/              (go code in package main)
-                    y.go
-        bin/
-            quux                   (installed command)
-		pkg/
-		    linux_amd64/
-		        foo/
-		            bar.a          (installed package object)
-
-Go searches each directory listed in GOPATH to find source code,
-but new packages are always downloaded into the first directory 
-in the list.
----
-
----  go help importpath
-Many commands apply to a set of packages named by import paths:
-
-	go action [importpath...]
-
-An import path that is a rooted path or that begins with
-a . or .. element is interpreted as a file system path and
-denotes the package in that directory.
-
-Otherwise, the import path P denotes the package found in
-the directory DIR/src/P for some DIR listed in the GOPATH
-environment variable (see 'go help gopath'). 
-
-If no import paths are given, the action applies to the
-package in the current directory.
-
-The special import path "all" expands to all package directories
-found in all the GOPATH trees.  For example, 'go list all' 
-lists all the packages on the local system.
-
-An import path can also name a package to be downloaded from
-a remote repository.  Run 'go help remote' for details.
-
-Every package in a program must have a unique import path.
-By convention, this is arranged by starting each path with a
-unique prefix that belongs to you.  For example, paths used
-internally at Google all begin with 'google', and paths
-denoting remote repositories begin with the path to the code,
-such as 'project.googlecode.com/'.
----
-
----  go help remote
-An import path (see 'go help importpath') denotes a package
-stored in the local file system.  Certain import paths also
-describe how to obtain the source code for the package using
-a revision control system.
-
-A few common code hosting sites have special syntax:
-
-	BitBucket (Mercurial)
-
-		import "bitbucket.org/user/project"
-		import "bitbucket.org/user/project/sub/directory"
-
-	GitHub (Git)
-
-		import "github.com/user/project"
-		import "github.com/user/project/sub/directory"
-
-	Google Code Project Hosting (Git, Mercurial, Subversion)
-
-		import "project.googlecode.com/git"
-		import "project.googlecode.com/git/sub/directory"
-
-		import "project.googlecode.com/hg"
-		import "project.googlecode.com/hg/sub/directory"
-
-		import "project.googlecode.com/svn/trunk"
-		import "project.googlecode.com/svn/trunk/sub/directory"
-
-	Launchpad (Bazaar)
-
-		import "launchpad.net/project"
-		import "launchpad.net/project/series"
-		import "launchpad.net/project/series/sub/directory"
-
-		import "launchpad.net/~user/project/branch"
-		import "launchpad.net/~user/project/branch/sub/directory"
-
-For code hosted on other servers, an import path of the form
-
-	repository.vcs/path
-
-specifies the given repository, with or without the .vcs suffix,
-using the named version control system, and then the path inside
-that repository.  The supported version control systems are:
-
-	Bazaar      .bzr
-	Git         .git
-	Mercurial   .hg
-	Subversion  .svn
-
-For example,
-
-	import "example.org/user/foo.hg"
-
-denotes the root directory of the Mercurial repository at
-example.org/user/foo or foo.hg, and
-
-	import "example.org/repo.git/foo/bar"
-
-denotes the foo/bar directory of the Git repository at
-example.com/repo or repo.git.
-
-When a version control system supports multiple protocols,
-each is tried in turn when downloading.  For example, a Git
-download tries git://, then https://, then http://.
-
-New downloaded packages are written to the first directory
-listed in the GOPATH environment variable (see 'go help gopath').
-
-The go command attempts to download the version of the
-package appropriate for the Go release being used.
-Run 'go help install' for more.
----
-
diff --git a/libgo/go/cmd/go/test.bash b/libgo/go/cmd/go/test.bash
deleted file mode 100755
index 0060ce2..0000000
--- a/libgo/go/cmd/go/test.bash
+++ /dev/null
@@ -1,820 +0,0 @@
-#!/bin/bash
-# Copyright 2012 The Go Authors.  All rights reserved.
-# Use of this source code is governed by a BSD-style
-# license that can be found in the LICENSE file.
-
-set -e
-go build -o testgo
-go() {
-	echo TEST ERROR: ran go, not testgo: go "$@" >&2
-	exit 2
-}
-
-started=false
-TEST() {
-	if $started; then
-		stop
-	fi
-	echo TEST: "$@"
-	started=true
-	ok=true
-}
-stop() {
-	if ! $started; then
-		echo TEST ERROR: stop missing start >&2
-		exit 2
-	fi
-	started=false
-	if $ok; then
-		echo PASS
-	else
-		echo FAIL
-		allok=false
-	fi
-}
-
-ok=true
-allok=true
-
-unset GOBIN
-unset GOPATH
-unset GOROOT
-
-TEST 'file:line in error messages'
-# Test that error messages have file:line information at beginning of
-# the line. Also test issue 4917: that the error is on stderr.
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-fn=$d/err.go
-echo "package main" > $fn
-echo 'import "bar"' >> $fn
-./testgo run $fn 2>$d/err.out || true
-if ! grep -q "^$fn:" $d/err.out; then
-	echo "missing file:line in error message"
-	cat $d/err.out
-	ok=false
-fi
-rm -r $d
-
-# Test local (./) imports.
-testlocal() {
-	local="$1"
-	TEST local imports $2 '(easy)'
-	./testgo build -o hello "testdata/$local/easy.go"
-	./hello >hello.out
-	if ! grep -q '^easysub\.Hello' hello.out; then
-		echo "testdata/$local/easy.go did not generate expected output"
-		cat hello.out
-		ok=false
-	fi
-	
-	TEST local imports $2 '(easysub)'
-	./testgo build -o hello "testdata/$local/easysub/main.go"
-	./hello >hello.out
-	if ! grep -q '^easysub\.Hello' hello.out; then
-		echo "testdata/$local/easysub/main.go did not generate expected output"
-		cat hello.out
-		ok=false
-	fi
-	
-	TEST local imports $2 '(hard)'
-	./testgo build -o hello "testdata/$local/hard.go"
-	./hello >hello.out
-	if ! grep -q '^sub\.Hello' hello.out || ! grep -q '^subsub\.Hello' hello.out ; then
-		echo "testdata/$local/hard.go did not generate expected output"
-		cat hello.out
-		ok=false
-	fi
-	
-	rm -f hello.out hello
-	
-	# Test that go install x.go fails.
-	TEST local imports $2 '(go install should fail)'
-	if ./testgo install "testdata/$local/easy.go" >/dev/null 2>&1; then
-		echo "go install testdata/$local/easy.go succeeded"
-		ok=false
-	fi
-}
-
-# Test local imports
-testlocal local ''
-
-# Test local imports again, with bad characters in the directory name.
-bad='#$%:, &()*;<=>?\^{}'
-rm -rf "testdata/$bad"
-cp -R testdata/local "testdata/$bad"
-testlocal "$bad" 'with bad characters in path'
-rm -rf "testdata/$bad"
-
-TEST error message for syntax error in test go file says FAIL
-export GOPATH=$(pwd)/testdata
-if ./testgo test syntaxerror 2>testdata/err; then
-	echo 'go test syntaxerror succeeded'
-	ok=false
-elif ! grep FAIL testdata/err >/dev/null; then
-	echo 'go test did not say FAIL:'
-	cat testdata/err
-	ok=false
-fi
-rm -f ./testdata/err
-unset GOPATH
-
-TEST wildcards do not look in useless directories
-export GOPATH=$(pwd)/testdata
-if ./testgo list ... >testdata/err 2>&1; then
-	echo "go list ... succeeded"
-	ok=false
-elif ! grep badpkg testdata/err >/dev/null; then
-	echo "go list ... failure does not mention badpkg"
-	cat testdata/err
-	ok=false
-elif ! ./testgo list m... >testdata/err 2>&1; then
-	echo "go list m... failed"
-	ok=false
-fi
-rm -rf ./testdata/err
-unset GOPATH
-
-# Test tests with relative imports.
-TEST relative imports '(go test)'
-if ! ./testgo test ./testdata/testimport; then
-	echo "go test ./testdata/testimport failed"
-	ok=false
-fi
-
-# Test installation with relative imports.
-TEST relative imports '(go test -i)'
-if ! ./testgo test -i ./testdata/testimport; then
-    echo "go test -i ./testdata/testimport failed"
-    ok=false
-fi
-
-# Test tests with relative imports in packages synthesized
-# from Go files named on the command line.
-TEST relative imports in command-line package
-if ! ./testgo test ./testdata/testimport/*.go; then
-	echo "go test ./testdata/testimport/*.go failed"
-	ok=false
-fi
-
-TEST version control error message includes correct directory
-export GOPATH=$(pwd)/testdata/shadow/root1
-if ./testgo get -u foo 2>testdata/err; then
-	echo "go get -u foo succeeded unexpectedly"
-	ok=false
-elif ! grep testdata/shadow/root1/src/foo testdata/err >/dev/null; then
-	echo "go get -u error does not mention shadow/root1/src/foo:"
-	cat testdata/err
-	ok=false
-fi
-unset GOPATH
-
-TEST go install fails with no buildable files
-export GOPATH=$(pwd)/testdata
-export CGO_ENABLED=0
-if ./testgo install cgotest 2>testdata/err; then
-	echo "go install cgotest succeeded unexpectedly"
-elif ! grep 'no buildable Go source files' testdata/err >/dev/null; then
-	echo "go install cgotest did not report 'no buildable Go source files'"
-	cat testdata/err
-	ok=false
-fi
-unset CGO_ENABLED
-unset GOPATH
-
-# Test that without $GOBIN set, binaries get installed
-# into the GOPATH bin directory.
-TEST install into GOPATH
-rm -rf testdata/bin
-if ! GOPATH=$(pwd)/testdata ./testgo install go-cmd-test; then
-	echo "go install go-cmd-test failed"
-	ok=false
-elif ! test -x testdata/bin/go-cmd-test; then
-	echo "go install go-cmd-test did not write to testdata/bin/go-cmd-test"
-	ok=false
-fi
-
-TEST package main_test imports archive not binary
-export GOBIN=$(pwd)/testdata/bin
-mkdir -p $GOBIN
-export GOPATH=$(pwd)/testdata
-touch ./testdata/src/main_test/m.go
-if ! ./testgo test main_test; then
-	echo "go test main_test failed without install"
-	ok=false
-elif ! ./testgo install main_test; then
-	echo "go test main_test failed"
-	ok=false
-elif [ "$(./testgo list -f '{{.Stale}}' main_test)" != false ]; then
-	echo "after go install, main listed as stale"
-	ok=false
-elif ! ./testgo test main_test; then
-	echo "go test main_test failed after install"
-	ok=false
-fi
-rm -rf $GOBIN
-unset GOBIN
-
-# And with $GOBIN set, binaries get installed to $GOBIN.
-TEST install into GOBIN
-if ! GOBIN=$(pwd)/testdata/bin1 GOPATH=$(pwd)/testdata ./testgo install go-cmd-test; then
-	echo "go install go-cmd-test failed"
-	ok=false
-elif ! test -x testdata/bin1/go-cmd-test; then
-	echo "go install go-cmd-test did not write to testdata/bin1/go-cmd-test"
-	ok=false
-fi
-
-# Without $GOBIN set, installing a program outside $GOPATH should fail
-# (there is nowhere to install it).
-TEST install without destination fails
-if ./testgo install testdata/src/go-cmd-test/helloworld.go 2>testdata/err; then
-	echo "go install testdata/src/go-cmd-test/helloworld.go should have failed, did not"
-	ok=false
-elif ! grep 'no install location for .go files listed on command line' testdata/err; then
-	echo "wrong error:"
-	cat testdata/err
-	ok=false
-fi
-rm -f testdata/err
-
-# With $GOBIN set, should install there.
-TEST install to GOBIN '(command-line package)'
-if ! GOBIN=$(pwd)/testdata/bin1 ./testgo install testdata/src/go-cmd-test/helloworld.go; then
-	echo "go install testdata/src/go-cmd-test/helloworld.go failed"
-	ok=false
-elif ! test -x testdata/bin1/helloworld; then
-	echo "go install testdata/src/go-cmd-test/helloworld.go did not write testdata/bin1/helloworld"
-	ok=false
-fi
-
-TEST godoc installs into GOBIN
-d=$(mktemp -d -t testgoXXX)
-export GOPATH=$d
-mkdir $d/gobin
-GOBIN=$d/gobin ./testgo get code.google.com/p/go.tools/cmd/godoc
-if [ ! -x $d/gobin/godoc ]; then
-	echo did not install godoc to '$GOBIN'
-	GOBIN=$d/gobin ./testgo list -f 'Target: {{.Target}}' code.google.com/p/go.tools/cmd/godoc
-	ok=false
-fi
-
-TEST godoc installs into GOROOT
-GOROOT=$(./testgo env GOROOT)
-rm -f $GOROOT/bin/godoc
-./testgo install code.google.com/p/go.tools/cmd/godoc
-if [ ! -x $GOROOT/bin/godoc ]; then
-	echo did not install godoc to '$GOROOT/bin'
-	./testgo list -f 'Target: {{.Target}}' code.google.com/p/go.tools/cmd/godoc
-	ok=false
-fi
-
-TEST cmd/fix installs into tool
-GOOS=$(./testgo env GOOS)
-GOARCH=$(./testgo env GOARCH)
-rm -f $GOROOT/pkg/tool/${GOOS}_${GOARCH}/fix
-./testgo install cmd/fix
-if [ ! -x $GOROOT/pkg/tool/${GOOS}_${GOARCH}/fix ]; then
-	echo 'did not install cmd/fix to $GOROOT/pkg/tool'
-	GOBIN=$d/gobin ./testgo list -f 'Target: {{.Target}}' cmd/fix
-	ok=false
-fi
-rm -f $GOROOT/pkg/tool/${GOOS}_${GOARCH}/fix
-GOBIN=$d/gobin ./testgo install cmd/fix
-if [ ! -x $GOROOT/pkg/tool/${GOOS}_${GOARCH}/fix ]; then
-	echo 'did not install cmd/fix to $GOROOT/pkg/tool with $GOBIN set'
-	GOBIN=$d/gobin ./testgo list -f 'Target: {{.Target}}' cmd/fix
-	ok=false
-fi
-
-TEST gopath program installs into GOBIN
-mkdir $d/src/progname
-echo 'package main; func main() {}' >$d/src/progname/p.go
-GOBIN=$d/gobin ./testgo install progname
-if [ ! -x $d/gobin/progname ]; then
-	echo 'did not install progname to $GOBIN/progname'
-	./testgo list -f 'Target: {{.Target}}' cmd/api
-	ok=false
-fi
-rm -f $d/gobin/progname $d/bin/progname
-
-TEST gopath program installs into GOPATH/bin
-./testgo install progname
-if [ ! -x $d/bin/progname ]; then
-	echo 'did not install progname to $GOPATH/bin/progname'
-	./testgo list -f 'Target: {{.Target}}' progname
-	ok=false
-fi
-
-unset GOPATH
-rm -rf $d
-
-# Reject relative paths in GOPATH.
-TEST reject relative paths in GOPATH '(command-line package)'
-if GOPATH=. ./testgo build testdata/src/go-cmd-test/helloworld.go; then
-    echo 'GOPATH="." go build should have failed, did not'
-    ok=false
-fi
-
-TEST reject relative paths in GOPATH 
-if GOPATH=:$(pwd)/testdata:. ./testgo build go-cmd-test; then
-    echo 'GOPATH=":$(pwd)/testdata:." go build should have failed, did not'
-    ok=false
-fi
-
-# issue 4104
-TEST go test with package listed multiple times
-if [ $(./testgo test fmt fmt fmt fmt fmt | wc -l) -ne 1 ] ; then
-    echo 'go test fmt fmt fmt fmt fmt tested the same package multiple times'
-    ok=false
-fi
-
-# ensure that output of 'go list' is consistent between runs
-TEST go list is consistent
-./testgo list std > test_std.list
-if ! ./testgo list std | cmp -s test_std.list - ; then
-	echo "go list std ordering is inconsistent"
-	ok=false
-fi
-rm -f test_std.list
-
-# issue 4096. Validate the output of unsuccessful go install foo/quxx 
-TEST unsuccessful go install should mention missing package
-if [ $(./testgo install 'foo/quxx' 2>&1 | grep -c 'cannot find package "foo/quxx" in any of') -ne 1 ] ; then
-	echo 'go install foo/quxx expected error: .*cannot find package "foo/quxx" in any of'
-	ok=false
-fi 
-# test GOROOT search failure is reported
-TEST GOROOT search failure reporting
-if [ $(./testgo install 'foo/quxx' 2>&1 | egrep -c 'foo/quxx \(from \$GOROOT\)$') -ne 1 ] ; then
-        echo 'go install foo/quxx expected error: .*foo/quxx (from $GOROOT)'
-        ok=false
-fi
-# test multiple GOPATH entries are reported separately
-TEST multiple GOPATH entries reported separately
-if [ $(GOPATH=$(pwd)/testdata/a:$(pwd)/testdata/b ./testgo install 'foo/quxx' 2>&1 | egrep -c 'testdata/./src/foo/quxx') -ne 2 ] ; then
-        echo 'go install foo/quxx expected error: .*testdata/a/src/foo/quxx (from $GOPATH)\n.*testdata/b/src/foo/quxx'
-        ok=false
-fi
-# test (from $GOPATH) annotation is reported for the first GOPATH entry
-TEST mention GOPATH in first GOPATH entry
-if [ $(GOPATH=$(pwd)/testdata/a:$(pwd)/testdata/b ./testgo install 'foo/quxx' 2>&1 | egrep -c 'testdata/a/src/foo/quxx \(from \$GOPATH\)$') -ne 1 ] ; then
-        echo 'go install foo/quxx expected error: .*testdata/a/src/foo/quxx (from $GOPATH)'
-        ok=false
-fi
-# but not on the second
-TEST but not the second entry
-if [ $(GOPATH=$(pwd)/testdata/a:$(pwd)/testdata/b ./testgo install 'foo/quxx' 2>&1 | egrep -c 'testdata/b/src/foo/quxx$') -ne 1 ] ; then
-        echo 'go install foo/quxx expected error: .*testdata/b/src/foo/quxx'
-        ok=false
-fi
-# test missing GOPATH is reported
-TEST missing GOPATH is reported
-if [ $(GOPATH= ./testgo install 'foo/quxx' 2>&1 | egrep -c '\(\$GOPATH not set\)$') -ne 1 ] ; then
-        echo 'go install foo/quxx expected error: ($GOPATH not set)'
-        ok=false
-fi
-
-# issue 4186. go get cannot be used to download packages to $GOROOT
-# Test that without GOPATH set, go get should fail
-TEST without GOPATH, go get fails
-d=$(mktemp -d -t testgoXXX)
-mkdir -p $d/src/pkg
-if GOPATH= GOROOT=$d ./testgo get -d code.google.com/p/go.codereview/cmd/hgpatch ; then 
-	echo 'go get code.google.com/p/go.codereview/cmd/hgpatch should not succeed with $GOPATH unset'
-	ok=false
-fi	
-rm -rf $d
-
-# Test that with GOPATH=$GOROOT, go get should fail
-TEST with GOPATH=GOROOT, go get fails
-d=$(mktemp -d -t testgoXXX)
-mkdir -p $d/src/pkg
-if GOPATH=$d GOROOT=$d ./testgo get -d code.google.com/p/go.codereview/cmd/hgpatch ; then
-        echo 'go get code.google.com/p/go.codereview/cmd/hgpatch should not succeed with GOPATH=$GOROOT'
-        ok=false
-fi
-rm -rf $d
-
-TEST ldflags arguments with spaces '(issue 3941)'
-d=$(mktemp -d -t testgoXXX)
-cat >$d/main.go<<EOF
-package main
-var extern string
-func main() {
-	println(extern)
-}
-EOF
-./testgo run -ldflags '-X main.extern "hello world"' $d/main.go 2>hello.out
-if ! grep -q '^hello world' hello.out; then
-	echo "ldflags -X main.extern 'hello world' failed. Output:"
-	cat hello.out
-	ok=false
-fi
-rm -rf $d hello.out
-
-TEST go test -cpuprofile leaves binary behind
-./testgo test -cpuprofile strings.prof strings || ok=false
-if [ ! -x strings.test ]; then
-	echo "go test -cpuprofile did not create strings.test"
-	ok=false
-fi
-rm -f strings.prof strings.test
-
-TEST symlinks do not confuse go list '(issue 4568)'
-old=$(pwd)
-tmp=$(cd /tmp && pwd -P)
-d=$(TMPDIR=$tmp mktemp -d -t testgoXXX)
-mkdir -p $d/src
-(
-	ln -s $d $d/src/dir1
-	cd $d/src
-	echo package p >dir1/p.go
-	export GOPATH=$d
-	if [ "$($old/testgo list -f '{{.Root}}' dir1)" != "$d" ]; then
-		echo Confused by symlinks.
-		echo "Package in current directory $(pwd) should have Root $d"
-		env|grep WD
-		$old/testgo list -json . dir1
-		touch $d/failed
-	fi		
-)
-if [ -f $d/failed ]; then
-	ok=false
-fi
-rm -rf $d
-
-TEST 'install with tags (issue 4515)'
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-mkdir -p $d/src/example/a $d/src/example/b $d/bin
-cat >$d/src/example/a/main.go <<EOF
-package main
-func main() {}
-EOF
-cat >$d/src/example/b/main.go <<EOF
-// +build mytag
-
-package main
-func main() {}
-EOF
-GOPATH=$d ./testgo install -tags mytag example/a example/b || ok=false
-if [ ! -x $d/bin/a -o ! -x $d/bin/b ]; then
-	echo go install example/a example/b did not install binaries
-	ok=false
-fi
-rm -f $d/bin/*
-GOPATH=$d ./testgo install -tags mytag example/... || ok=false
-if [ ! -x $d/bin/a -o ! -x $d/bin/b ]; then
-	echo go install example/... did not install binaries
-	ok=false
-fi
-rm -f $d/bin/*go
-export GOPATH=$d
-if [ "$(./testgo list -tags mytag example/b...)" != "example/b" ]; then
-	echo go list example/b did not find example/b
-	ok=false
-fi
-unset GOPATH
-rm -rf $d
-
-TEST case collisions '(issue 4773)'
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-export GOPATH=$d
-mkdir -p $d/src/example/{a/pkg,a/Pkg,b}
-cat >$d/src/example/a/a.go <<EOF
-package p
-import (
-	_ "example/a/pkg"
-	_ "example/a/Pkg"
-)
-EOF
-cat >$d/src/example/a/pkg/pkg.go <<EOF
-package pkg
-EOF
-cat >$d/src/example/a/Pkg/pkg.go <<EOF
-package pkg
-EOF
-if ./testgo list example/a 2>$d/out; then
-	echo go list example/a should have failed, did not.
-	ok=false
-elif ! grep "case-insensitive import collision" $d/out >/dev/null; then
-	echo go list example/a did not report import collision.
-	ok=false
-fi
-cat >$d/src/example/b/file.go <<EOF
-package b
-EOF
-cat >$d/src/example/b/FILE.go <<EOF
-package b
-EOF
-if [ $(ls $d/src/example/b | wc -l) = 2 ]; then
-	# case-sensitive file system, let directory read find both files
-	args="example/b"
-else
-	# case-insensitive file system, list files explicitly on command line.
-	args="$d/src/example/b/file.go $d/src/example/b/FILE.go"
-fi
-if ./testgo list $args 2>$d/out; then
-	echo go list example/b should have failed, did not.
-	ok=false
-elif ! grep "case-insensitive file name collision" $d/out >/dev/null; then
-	echo go list example/b did not report file name collision.
-	ok=false
-fi
-
-TEST go get cover
-./testgo get code.google.com/p/go.tools/cmd/cover || ok=false
-
-unset GOPATH
-rm -rf $d
-
-TEST shadowing logic
-export GOPATH=$(pwd)/testdata/shadow/root1:$(pwd)/testdata/shadow/root2
-
-# The math in root1 is not "math" because the standard math is.
-cdir=$(./testgo list -f '({{.ImportPath}}) ({{.ConflictDir}})' ./testdata/shadow/root1/src/math)
-if [ "$cdir" != "(_$(pwd)/testdata/shadow/root1/src/math) ($GOROOT/src/pkg/math)" ]; then
-	echo shadowed math is not shadowed: "$cdir"
-	ok=false
-fi
-
-# The foo in root1 is "foo".
-cdir=$(./testgo list -f '({{.ImportPath}}) ({{.ConflictDir}})' ./testdata/shadow/root1/src/foo)
-if [ "$cdir" != "(foo) ()" ]; then
-	echo unshadowed foo is shadowed: "$cdir"
-	ok=false
-fi
-
-# The foo in root2 is not "foo" because the foo in root1 got there first.
-cdir=$(./testgo list -f '({{.ImportPath}}) ({{.ConflictDir}})' ./testdata/shadow/root2/src/foo)
-if [ "$cdir" != "(_$(pwd)/testdata/shadow/root2/src/foo) ($(pwd)/testdata/shadow/root1/src/foo)" ]; then
-	echo shadowed foo is not shadowed: "$cdir"
-	ok=false
-fi
-
-# The error for go install should mention the conflicting directory.
-err=$(! ./testgo install ./testdata/shadow/root2/src/foo 2>&1)
-if [ "$err" != "go install: no install location for $(pwd)/testdata/shadow/root2/src/foo: hidden by $(pwd)/testdata/shadow/root1/src/foo" ]; then
-	echo wrong shadowed install error: "$err"
-	ok=false
-fi
-
-# Only succeeds if source order is preserved.
-TEST source file name order preserved
-./testgo test testdata/example[12]_test.go || ok=false
-
-# Check that coverage analysis works at all.
-# Don't worry about the exact numbers but require not 0.0%.
-checkcoverage() {
-	if grep '[^0-9]0\.0%' testdata/cover.txt >/dev/null; then
-		echo 'some coverage results are 0.0%'
-		ok=false
-	fi
-	cat testdata/cover.txt
-	rm -f testdata/cover.txt
-}
-	
-TEST coverage runs
-./testgo test -short -coverpkg=strings strings regexp >testdata/cover.txt 2>&1 || ok=false
-./testgo test -short -cover strings math regexp >>testdata/cover.txt 2>&1 || ok=false
-checkcoverage
-
-# Check that coverage analysis uses set mode.
-TEST coverage uses set mode
-if ./testgo test -short -cover encoding/binary -coverprofile=testdata/cover.out >testdata/cover.txt 2>&1; then
-	if ! grep -q 'mode: set' testdata/cover.out; then
-		ok=false
-	fi
-	checkcoverage
-else
-	ok=false
-fi
-rm -f testdata/cover.out testdata/cover.txt
-
-TEST coverage uses atomic mode for -race.
-if ./testgo test -short -race -cover encoding/binary -coverprofile=testdata/cover.out >testdata/cover.txt 2>&1; then
-	if ! grep -q 'mode: atomic' testdata/cover.out; then
-		ok=false
-	fi
-	checkcoverage
-else
-	ok=false
-fi
-rm -f testdata/cover.out
-
-TEST coverage uses actual setting to override even for -race.
-if ./testgo test -short -race -cover encoding/binary -covermode=count -coverprofile=testdata/cover.out >testdata/cover.txt 2>&1; then
-	if ! grep -q 'mode: count' testdata/cover.out; then
-		ok=false
-	fi
-	checkcoverage
-else
-	ok=false
-fi
-rm -f testdata/cover.out
-
-TEST coverage with cgo
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-./testgo test -short -cover ./testdata/cgocover >testdata/cover.txt 2>&1 || ok=false
-checkcoverage
-
-TEST cgo depends on syscall
-rm -rf $GOROOT/pkg/*_race
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-export GOPATH=$d
-mkdir -p $d/src/foo
-echo '
-package foo
-//#include <stdio.h>
-import "C"
-' >$d/src/foo/foo.go
-./testgo build -race foo || ok=false
-rm -rf $d
-unset GOPATH
-
-TEST cgo shows full path names
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-export GOPATH=$d
-mkdir -p $d/src/x/y/dirname
-echo '
-package foo
-import "C"
-func f() {
-' >$d/src/x/y/dirname/foo.go
-if ./testgo build x/y/dirname >$d/err 2>&1; then
-	echo build succeeded unexpectedly.
-	ok=false
-elif ! grep x/y/dirname $d/err >/dev/null; then
-	echo error did not use full path.
-	cat $d/err
-	ok=false
-fi
-rm -rf $d
-unset GOPATH
-
-TEST 'cgo handles -Wl,$ORIGIN'
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-export GOPATH=$d
-mkdir -p $d/src/origin
-echo '
-package origin
-// #cgo !darwin LDFLAGS: -Wl,-rpath -Wl,$ORIGIN
-// void f(void) {}
-import "C"
-
-func f() { C.f() }
-' >$d/src/origin/origin.go
-if ! ./testgo build origin; then
-	echo build failed
-	ok=false
-fi
-rm -rf $d
-unset GOPATH
-
-TEST 'Issue 6480: "go test -c -test.bench=XXX fmt" should not hang'
-if ! ./testgo test -c -test.bench=XXX fmt; then
-	echo build test failed
-	ok=false
-fi
-rm -f fmt.test
-
-TEST 'Issue 7573: cmd/cgo: undefined reference when linking a C-library using gccgo'
-d=$(mktemp -d -t testgoXXX)
-export GOPATH=$d
-mkdir -p $d/src/cgoref
-ldflags="-L alibpath -lalib"
-echo "
-package main
-// #cgo LDFLAGS: $ldflags
-// void f(void) {}
-import \"C\"
-
-func main() { C.f() }
-" >$d/src/cgoref/cgoref.go
-go_cmds="$(./testgo build -n -compiler gccgo cgoref 2>&1 1>/dev/null)"
-ldflags_count="$(echo "$go_cmds" | egrep -c "^gccgo.*$(echo $ldflags | sed -e 's/-/\\-/g')" || true)"
-if [ "$ldflags_count" -lt 1 ]; then
-	echo "No Go-inline "#cgo LDFLAGS:" (\"$ldflags\") passed to gccgo linking stage."
-	ok=false
-fi
-rm -rf $d
-unset ldflags_count
-unset go_cmds
-unset ldflags
-unset GOPATH
-
-TEST list template can use context function
-if ! ./testgo list -f "GOARCH: {{context.GOARCH}}"; then 
-	echo unable to use context in list template
-	ok=false
-fi
-
-TEST 'Issue 7108: cmd/go: "go test" should fail if package does not build'
-export GOPATH=$(pwd)/testdata
-if ./testgo test notest >/dev/null 2>&1; then
-	echo 'go test notest succeeded, but should fail'
-	ok=false
-fi
-unset GOPATH
-
-TEST 'Issue 6844: cmd/go: go test -a foo does not rebuild regexp'
-if ! ./testgo test -x -a -c testdata/dep_test.go 2>deplist; then
-	echo "go test -x -a -c testdata/dep_test.go failed"
-	ok=false
-elif ! grep -q regexp deplist; then
-	echo "go test -x -a -c testdata/dep_test.go did not rebuild regexp"
-	ok=false
-fi
-rm -f deplist
-rm -f deps.test
-
-TEST list template can use context function
-if ! ./testgo list -f "GOARCH: {{context.GOARCH}}"; then 
-	echo unable to use context in list template
-	ok=false
-fi
-
-TEST build -i installs dependencies
-d=$(TMPDIR=/var/tmp mktemp -d -t testgoXXX)
-export GOPATH=$d
-mkdir -p $d/src/x/y/foo $d/src/x/y/bar
-echo '
-package foo
-func F() {}
-' >$d/src/x/y/foo/foo.go
-echo '
-package bar
-import "x/y/foo"
-func F() { foo.F() }
-' >$d/src/x/y/bar/bar.go
-if ! ./testgo build -v -i x/y/bar &> $d/err; then
-	echo build -i failed
-	cat $d/err
-	ok=false
-elif ! grep x/y/foo $d/err >/dev/null; then
-	echo first build -i did not build x/y/foo
-	cat $d/err
-	ok=false
-fi
-if ! ./testgo build -v -i x/y/bar &> $d/err; then
-	echo second build -i failed
-	cat $d/err
-	ok=false
-elif grep x/y/foo $d/err >/dev/null; then
-	echo second build -i built x/y/foo
-	cat $d/err
-	ok=false
-fi
-rm -rf $d
-unset GOPATH
-
-TEST 'go build in test-only directory fails with a good error'
-if ./testgo build ./testdata/testonly 2>testdata/err.out; then
-	echo "go build ./testdata/testonly succeeded, should have failed"
-	ok=false
-elif ! grep 'no buildable Go' testdata/err.out >/dev/null; then
-	echo "go build ./testdata/testonly produced unexpected error:"
-	cat testdata/err.out
-	ok=false
-fi
-rm -f testdata/err.out
-
-TEST 'go test detects test-only import cycles'
-export GOPATH=$(pwd)/testdata
-if ./testgo test -c testcycle/p3 2>testdata/err.out; then
-	echo "go test testcycle/p3 succeeded, should have failed"
-	ok=false
-elif ! grep 'import cycle not allowed in test' testdata/err.out >/dev/null; then
-	echo "go test testcycle/p3 produced unexpected error:"
-	cat testdata/err.out
-	ok=false
-fi
-rm -f testdata/err.out
-unset GOPATH
-
-TEST 'go test foo_test.go works'
-if ! ./testgo test testdata/standalone_test.go; then
-	echo "go test testdata/standalone_test.go failed"
-	ok=false
-fi
-
-TEST 'go test xtestonly works'
-export GOPATH=$(pwd)/testdata
-./testgo clean -i xtestonly
-if ! ./testgo test xtestonly >/dev/null; then
-	echo "go test xtestonly failed"
-	ok=false
-fi
-unset GOPATH
-
-
-# clean up
-if $started; then stop; fi
-rm -rf testdata/bin testdata/bin1
-rm -f testgo
-
-if $allok; then
-	echo PASS
-else
-	echo FAIL
-	exit 1
-fi
diff --git a/libgo/go/cmd/go/testdata/src/bench/x_test.go b/libgo/go/cmd/go/testdata/src/bench/x_test.go
new file mode 100644
index 0000000..32cabf8
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/bench/x_test.go
@@ -0,0 +1,6 @@
+package bench
+
+import "testing"
+
+func Benchmark(b *testing.B) {
+}
diff --git a/libgo/go/cmd/go/testdata/src/cgoasm/p.go b/libgo/go/cmd/go/testdata/src/cgoasm/p.go
new file mode 100644
index 0000000..148b47f
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/cgoasm/p.go
@@ -0,0 +1,8 @@
+package p
+
+/*
+// hi
+*/
+import "C"
+
+func F() {}
diff --git a/libgo/go/cmd/go/testdata/src/cgoasm/p.s b/libgo/go/cmd/go/testdata/src/cgoasm/p.s
new file mode 100644
index 0000000..aaade03
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/cgoasm/p.s
@@ -0,0 +1,2 @@
+TEXT asm(SB),$0
+	RET
diff --git a/libgo/go/cmd/go/testdata/src/exclude/empty/x.txt b/libgo/go/cmd/go/testdata/src/exclude/empty/x.txt
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/exclude/empty/x.txt
diff --git a/libgo/go/cmd/go/testdata/src/exclude/ignore/_x.go b/libgo/go/cmd/go/testdata/src/exclude/ignore/_x.go
new file mode 100644
index 0000000..823aafd
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/exclude/ignore/_x.go
@@ -0,0 +1 @@
+package x
diff --git a/libgo/go/cmd/go/testdata/src/exclude/x.go b/libgo/go/cmd/go/testdata/src/exclude/x.go
new file mode 100644
index 0000000..9affd21
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/exclude/x.go
@@ -0,0 +1,3 @@
+// +build linux,!linux
+
+package x
diff --git a/libgo/go/cmd/go/testdata/src/exclude/x_linux.go b/libgo/go/cmd/go/testdata/src/exclude/x_linux.go
new file mode 100644
index 0000000..41ef6e5
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/exclude/x_linux.go
@@ -0,0 +1,3 @@
+// +build windows
+
+package x
diff --git a/libgo/go/cmd/go/testdata/src/testlist/bench_test.go b/libgo/go/cmd/go/testdata/src/testlist/bench_test.go
new file mode 100644
index 0000000..22f147b
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/testlist/bench_test.go
@@ -0,0 +1,14 @@
+package testlist
+
+import (
+	"fmt"
+	"testing"
+)
+
+func BenchmarkSimplefunc(b *testing.B) {
+	b.StopTimer()
+	b.StartTimer()
+	for i := 0; i < b.N; i++ {
+		_ = fmt.Sprint("Test for bench")
+	}
+}
diff --git a/libgo/go/cmd/go/testdata/src/testlist/example_test.go b/libgo/go/cmd/go/testdata/src/testlist/example_test.go
new file mode 100644
index 0000000..0298dfd
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/testlist/example_test.go
@@ -0,0 +1,21 @@
+package testlist
+
+import (
+	"fmt"
+)
+
+func ExampleSimple() {
+	fmt.Println("Test with Output.")
+
+	// Output: Test with Output.
+}
+
+func ExampleWithEmptyOutput() {
+	fmt.Println("")
+
+	// Output:
+}
+
+func ExampleNoOutput() {
+	_ = fmt.Sprint("Test with no output")
+}
diff --git a/libgo/go/cmd/go/testdata/src/testlist/test_test.go b/libgo/go/cmd/go/testdata/src/testlist/test_test.go
new file mode 100644
index 0000000..bdc09f2
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/testlist/test_test.go
@@ -0,0 +1,10 @@
+package testlist
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestSimple(t *testing.T) {
+	_ = fmt.Sprint("Test simple")
+}
diff --git a/libgo/go/cmd/go/testdata/src/testregexp/x_test.go b/libgo/go/cmd/go/testdata/src/testregexp/x_test.go
new file mode 100644
index 0000000..7573e79
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/testregexp/x_test.go
@@ -0,0 +1,17 @@
+package x
+
+import "testing"
+
+func TestX(t *testing.T) {
+	t.Logf("LOG: X running")
+	t.Run("Y", func(t *testing.T) {
+		t.Logf("LOG: Y running")
+	})
+}
+
+func BenchmarkX(b *testing.B) {
+	b.Logf("LOG: X running N=%d", b.N)
+	b.Run("Y", func(b *testing.B) {
+		b.Logf("LOG: Y running N=%d", b.N)
+	})
+}
diff --git a/libgo/go/cmd/go/testdata/src/testregexp/z_test.go b/libgo/go/cmd/go/testdata/src/testregexp/z_test.go
new file mode 100644
index 0000000..4fd1979
--- /dev/null
+++ b/libgo/go/cmd/go/testdata/src/testregexp/z_test.go
@@ -0,0 +1,19 @@
+package x
+
+import "testing"
+
+func TestZ(t *testing.T) {
+	t.Logf("LOG: Z running")
+}
+
+func TestXX(t *testing.T) {
+	t.Logf("LOG: XX running")
+}
+
+func BenchmarkZ(b *testing.B) {
+	b.Logf("LOG: Z running N=%d", b.N)
+}
+
+func BenchmarkXX(b *testing.B) {
+	b.Logf("LOG: XX running N=%d", b.N)
+}
diff --git a/libgo/go/cmd/go/testflag.go b/libgo/go/cmd/go/testflag.go
deleted file mode 100644
index fa53bfc..0000000
--- a/libgo/go/cmd/go/testflag.go
+++ /dev/null
@@ -1,294 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
-	"flag"
-	"fmt"
-	"os"
-	"strconv"
-	"strings"
-)
-
-// The flag handling part of go test is large and distracting.
-// We can't use the flag package because some of the flags from
-// our command line are for us, and some are for 6.out, and
-// some are for both.
-
-// testFlagSpec defines a flag we know about.
-type testFlagSpec struct {
-	name       string
-	boolVar    *bool
-	flagValue  flag.Value
-	passToTest bool // pass to Test
-	multiOK    bool // OK to have multiple instances
-	present    bool // flag has been seen
-}
-
-// testFlagDefn is the set of flags we process.
-var testFlagDefn = []*testFlagSpec{
-	// local.
-	{name: "c", boolVar: &testC},
-	{name: "i", boolVar: &buildI},
-	{name: "o"},
-	{name: "cover", boolVar: &testCover},
-	{name: "covermode"},
-	{name: "coverpkg"},
-	{name: "exec"},
-
-	// passed to 6.out, adding a "test." prefix to the name if necessary: -v becomes -test.v.
-	{name: "bench", passToTest: true},
-	{name: "benchmem", boolVar: new(bool), passToTest: true},
-	{name: "benchtime", passToTest: true},
-	{name: "count", passToTest: true},
-	{name: "coverprofile", passToTest: true},
-	{name: "cpu", passToTest: true},
-	{name: "cpuprofile", passToTest: true},
-	{name: "memprofile", passToTest: true},
-	{name: "memprofilerate", passToTest: true},
-	{name: "blockprofile", passToTest: true},
-	{name: "blockprofilerate", passToTest: true},
-	{name: "mutexprofile", passToTest: true},
-	{name: "mutexprofilefraction", passToTest: true},
-	{name: "outputdir", passToTest: true},
-	{name: "parallel", passToTest: true},
-	{name: "run", passToTest: true},
-	{name: "short", boolVar: new(bool), passToTest: true},
-	{name: "timeout", passToTest: true},
-	{name: "trace", passToTest: true},
-	{name: "v", boolVar: &testV, passToTest: true},
-}
-
-// add build flags to testFlagDefn
-func init() {
-	var cmd Command
-	addBuildFlags(&cmd)
-	cmd.Flag.VisitAll(func(f *flag.Flag) {
-		if f.Name == "v" {
-			// test overrides the build -v flag
-			return
-		}
-		testFlagDefn = append(testFlagDefn, &testFlagSpec{
-			name:      f.Name,
-			flagValue: f.Value,
-		})
-	})
-}
-
-// testFlags processes the command line, grabbing -x and -c, rewriting known flags
-// to have "test" before them, and reading the command line for the 6.out.
-// Unfortunately for us, we need to do our own flag processing because go test
-// grabs some flags but otherwise its command line is just a holding place for
-// pkg.test's arguments.
-// We allow known flags both before and after the package name list,
-// to allow both
-//	go test fmt -custom-flag-for-fmt-test
-//	go test -x math
-func testFlags(args []string) (packageNames, passToTest []string) {
-	inPkg := false
-	outputDir := ""
-	var explicitArgs []string
-	for i := 0; i < len(args); i++ {
-		if !strings.HasPrefix(args[i], "-") {
-			if !inPkg && packageNames == nil {
-				// First package name we've seen.
-				inPkg = true
-			}
-			if inPkg {
-				packageNames = append(packageNames, args[i])
-				continue
-			}
-		}
-
-		if inPkg {
-			// Found an argument beginning with "-"; end of package list.
-			inPkg = false
-		}
-
-		f, value, extraWord := testFlag(args, i)
-		if f == nil {
-			// This is a flag we do not know; we must assume
-			// that any args we see after this might be flag
-			// arguments, not package names.
-			inPkg = false
-			if packageNames == nil {
-				// make non-nil: we have seen the empty package list
-				packageNames = []string{}
-			}
-			if args[i] == "-args" || args[i] == "--args" {
-				// -args or --args signals that everything that follows
-				// should be passed to the test.
-				explicitArgs = args[i+1:]
-				break
-			}
-			passToTest = append(passToTest, args[i])
-			continue
-		}
-		if f.flagValue != nil {
-			if err := f.flagValue.Set(value); err != nil {
-				fatalf("invalid flag argument for -%s: %v", f.name, err)
-			}
-		} else {
-			// Test-only flags.
-			// Arguably should be handled by f.flagValue, but aren't.
-			var err error
-			switch f.name {
-			// bool flags.
-			case "c", "i", "v", "cover":
-				setBoolFlag(f.boolVar, value)
-			case "o":
-				testO = value
-				testNeedBinary = true
-			case "exec":
-				execCmd, err = splitQuotedFields(value)
-				if err != nil {
-					fatalf("invalid flag argument for -%s: %v", f.name, err)
-				}
-			case "bench":
-				// record that we saw the flag; don't care about the value
-				testBench = true
-			case "timeout":
-				testTimeout = value
-			case "blockprofile", "cpuprofile", "memprofile", "mutexprofile":
-				testProfile = true
-				testNeedBinary = true
-			case "trace":
-				testProfile = true
-			case "coverpkg":
-				testCover = true
-				if value == "" {
-					testCoverPaths = nil
-				} else {
-					testCoverPaths = strings.Split(value, ",")
-				}
-			case "coverprofile":
-				testCover = true
-				testProfile = true
-			case "covermode":
-				switch value {
-				case "set", "count", "atomic":
-					testCoverMode = value
-				default:
-					fatalf("invalid flag argument for -covermode: %q", value)
-				}
-				testCover = true
-			case "outputdir":
-				outputDir = value
-			}
-		}
-		if extraWord {
-			i++
-		}
-		if f.passToTest {
-			passToTest = append(passToTest, "-test."+f.name+"="+value)
-		}
-	}
-
-	if testCoverMode == "" {
-		testCoverMode = "set"
-		if buildRace {
-			// Default coverage mode is atomic when -race is set.
-			testCoverMode = "atomic"
-		}
-	}
-
-	// Tell the test what directory we're running in, so it can write the profiles there.
-	if testProfile && outputDir == "" {
-		dir, err := os.Getwd()
-		if err != nil {
-			fatalf("error from os.Getwd: %s", err)
-		}
-		passToTest = append(passToTest, "-test.outputdir", dir)
-	}
-
-	passToTest = append(passToTest, explicitArgs...)
-	return
-}
-
-// testFlag sees if argument i is a known flag and returns its definition, value, and whether it consumed an extra word.
-func testFlag(args []string, i int) (f *testFlagSpec, value string, extra bool) {
-	arg := args[i]
-	if strings.HasPrefix(arg, "--") { // reduce two minuses to one
-		arg = arg[1:]
-	}
-	switch arg {
-	case "-?", "-h", "-help":
-		usage()
-	}
-	if arg == "" || arg[0] != '-' {
-		return
-	}
-	name := arg[1:]
-	// If there's already "test.", drop it for now.
-	name = strings.TrimPrefix(name, "test.")
-	equals := strings.Index(name, "=")
-	if equals >= 0 {
-		value = name[equals+1:]
-		name = name[:equals]
-	}
-	for _, f = range testFlagDefn {
-		if name == f.name {
-			// Booleans are special because they have modes -x, -x=true, -x=false.
-			if f.boolVar != nil || isBoolFlag(f.flagValue) {
-				if equals < 0 { // otherwise, it's been set and will be verified in setBoolFlag
-					value = "true"
-				} else {
-					// verify it parses
-					setBoolFlag(new(bool), value)
-				}
-			} else { // Non-booleans must have a value.
-				extra = equals < 0
-				if extra {
-					if i+1 >= len(args) {
-						testSyntaxError("missing argument for flag " + f.name)
-					}
-					value = args[i+1]
-				}
-			}
-			if f.present && !f.multiOK {
-				testSyntaxError(f.name + " flag may be set only once")
-			}
-			f.present = true
-			return
-		}
-	}
-	f = nil
-	return
-}
-
-// isBoolFlag reports whether v is a bool flag.
-func isBoolFlag(v flag.Value) bool {
-	vv, ok := v.(interface {
-		IsBoolFlag() bool
-	})
-	if ok {
-		return vv.IsBoolFlag()
-	}
-	return false
-}
-
-// setBoolFlag sets the addressed boolean to the value.
-func setBoolFlag(flag *bool, value string) {
-	x, err := strconv.ParseBool(value)
-	if err != nil {
-		testSyntaxError("illegal bool flag value " + value)
-	}
-	*flag = x
-}
-
-// setIntFlag sets the addressed integer to the value.
-func setIntFlag(flag *int, value string) {
-	x, err := strconv.Atoi(value)
-	if err != nil {
-		testSyntaxError("illegal int flag value " + value)
-	}
-	*flag = x
-}
-
-func testSyntaxError(msg string) {
-	fmt.Fprintf(os.Stderr, "go test: %s\n", msg)
-	fmt.Fprintf(os.Stderr, `run "go help test" or "go help testflag" for more information`+"\n")
-	os.Exit(2)
-}
diff --git a/libgo/go/cmd/go/tool.go b/libgo/go/cmd/go/tool.go
deleted file mode 100644
index 6e2c68f..0000000
--- a/libgo/go/cmd/go/tool.go
+++ /dev/null
@@ -1,173 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
-	"fmt"
-	"go/build"
-	"os"
-	"os/exec"
-	"path/filepath"
-	"runtime"
-	"sort"
-	"strings"
-)
-
-var cmdTool = &Command{
-	Run:       runTool,
-	UsageLine: "tool [-n] command [args...]",
-	Short:     "run specified go tool",
-	Long: `
-Tool runs the go tool command identified by the arguments.
-With no arguments it prints the list of known tools.
-
-The -n flag causes tool to print the command that would be
-executed but not execute it.
-
-For more about each tool command, see 'go tool command -h'.
-`,
-}
-
-var (
-	toolGOOS      = runtime.GOOS
-	toolGOARCH    = runtime.GOARCH
-	toolIsWindows = toolGOOS == "windows"
-	toolDir       = build.ToolDir
-
-	toolN bool
-)
-
-// List of go tools found in the gccgo tool directory.
-// Other binaries could be in the same directory so don't
-// show those with the 'go tool' command.
-
-var gccgoTools = []string{"cgo", "fix", "cover", "godoc", "vet"}
-
-func init() {
-	cmdTool.Flag.BoolVar(&toolN, "n", false, "")
-}
-
-const toolWindowsExtension = ".exe"
-
-func tool(toolName string) string {
-	toolPath := filepath.Join(toolDir, toolName)
-	if toolIsWindows {
-		toolPath += toolWindowsExtension
-	}
-	if len(buildToolExec) > 0 {
-		return toolPath
-	}
-	// Give a nice message if there is no tool with that name.
-	if _, err := os.Stat(toolPath); err != nil {
-		if isInGoToolsRepo(toolName) {
-			fmt.Fprintf(os.Stderr, "go tool: no such tool %q; to install:\n\tgo get golang.org/x/tools/cmd/%s\n", toolName, toolName)
-		} else {
-			fmt.Fprintf(os.Stderr, "go tool: no such tool %q\n", toolName)
-		}
-		setExitStatus(2)
-		exit()
-	}
-	return toolPath
-}
-
-func isInGoToolsRepo(toolName string) bool {
-	return false
-}
-
-func runTool(cmd *Command, args []string) {
-	if len(args) == 0 {
-		listTools()
-		return
-	}
-	toolName := args[0]
-	// The tool name must be lower-case letters, numbers or underscores.
-	for _, c := range toolName {
-		switch {
-		case 'a' <= c && c <= 'z', '0' <= c && c <= '9', c == '_':
-		default:
-			fmt.Fprintf(os.Stderr, "go tool: bad tool name %q\n", toolName)
-			setExitStatus(2)
-			return
-		}
-	}
-	toolPath := tool(toolName)
-	if toolPath == "" {
-		return
-	}
-	if toolN {
-		cmd := toolPath
-		if len(args) > 1 {
-			cmd += " " + strings.Join(args[1:], " ")
-		}
-		fmt.Printf("%s\n", cmd)
-		return
-	}
-	args[0] = toolPath // in case the tool wants to re-exec itself, e.g. cmd/dist
-	toolCmd := &exec.Cmd{
-		Path:   toolPath,
-		Args:   args,
-		Stdin:  os.Stdin,
-		Stdout: os.Stdout,
-		Stderr: os.Stderr,
-		// Set $GOROOT, mainly for go tool dist.
-		Env: mergeEnvLists([]string{"GOROOT=" + goroot}, os.Environ()),
-	}
-	err := toolCmd.Run()
-	if err != nil {
-		// Only print about the exit status if the command
-		// didn't even run (not an ExitError) or it didn't exit cleanly
-		// or we're printing command lines too (-x mode).
-		// Assume if command exited cleanly (even with non-zero status)
-		// it printed any messages it wanted to print.
-		if e, ok := err.(*exec.ExitError); !ok || !e.Exited() || buildX {
-			fmt.Fprintf(os.Stderr, "go tool %s: %s\n", toolName, err)
-		}
-		setExitStatus(1)
-		return
-	}
-}
-
-// listTools prints a list of the available tools in the tools directory.
-func listTools() {
-	f, err := os.Open(toolDir)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "go tool: no tool directory: %s\n", err)
-		setExitStatus(2)
-		return
-	}
-	defer f.Close()
-	names, err := f.Readdirnames(-1)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "go tool: can't read directory: %s\n", err)
-		setExitStatus(2)
-		return
-	}
-
-	sort.Strings(names)
-	for _, name := range names {
-		// Unify presentation by going to lower case.
-		name = strings.ToLower(name)
-		// If it's windows, don't show the .exe suffix.
-		if toolIsWindows && strings.HasSuffix(name, toolWindowsExtension) {
-			name = name[:len(name)-len(toolWindowsExtension)]
-		}
-
-		// The tool directory used by gccgo will have other binaries
-		// in additions to go tools.  Only display go tools for this list.
-
-		if buildContext.Compiler == "gccgo" {
-			for _, tool := range gccgoTools {
-				if tool == name {
-					fmt.Println(name)
-				}
-			}
-		} else {
-
-			// Not gccgo, list all the tools found in this dir
-
-			fmt.Println(name)
-		}
-	}
-}
diff --git a/libgo/go/cmd/go/vendor_test.go b/libgo/go/cmd/go/vendor_test.go
index deec02e..739ce5a 100644
--- a/libgo/go/cmd/go/vendor_test.go
+++ b/libgo/go/cmd/go/vendor_test.go
@@ -20,18 +20,18 @@
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata"))
-	tg.run("list", "-f", "{{.ImportPath}} {{.Imports}}", "vend/...")
+	tg.run("list", "-f", "{{.ImportPath}} {{.Imports}}", "vend/...", "vend/vendor/...", "vend/x/vendor/...")
 	want := `
 		vend [vend/vendor/p r]
 		vend/dir1 []
 		vend/hello [fmt vend/vendor/strings]
 		vend/subdir [vend/vendor/p r]
+		vend/x [vend/x/vendor/p vend/vendor/q vend/x/vendor/r vend/dir1 vend/vendor/vend/dir1/dir2]
+		vend/x/invalid [vend/x/invalid/vendor/foo]
 		vend/vendor/p []
 		vend/vendor/q []
 		vend/vendor/strings []
 		vend/vendor/vend/dir1/dir2 []
-		vend/x [vend/x/vendor/p vend/vendor/q vend/x/vendor/r vend/dir1 vend/vendor/vend/dir1/dir2]
-		vend/x/invalid [vend/x/invalid/vendor/foo]
 		vend/x/vendor/p []
 		vend/x/vendor/p/p [notfound]
 		vend/x/vendor/r []
diff --git a/libgo/go/cmd/go/vet.go b/libgo/go/cmd/go/vet.go
deleted file mode 100644
index 8e296c8..0000000
--- a/libgo/go/cmd/go/vet.go
+++ /dev/null
@@ -1,52 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import "path/filepath"
-
-func init() {
-	addBuildFlags(cmdVet)
-}
-
-var cmdVet = &Command{
-	Run:       runVet,
-	UsageLine: "vet [-n] [-x] [build flags] [packages]",
-	Short:     "run go tool vet on packages",
-	Long: `
-Vet runs the Go vet command on the packages named by the import paths.
-
-For more about vet, see 'go doc cmd/vet'.
-For more about specifying packages, see 'go help packages'.
-
-To run the vet tool with specific options, run 'go tool vet'.
-
-The -n flag prints commands that would be executed.
-The -x flag prints commands as they are executed.
-
-For more about build flags, see 'go help build'.
-
-See also: go fmt, go fix.
-	`,
-}
-
-func runVet(cmd *Command, args []string) {
-	for _, p := range packages(args) {
-		// Vet expects to be given a set of files all from the same package.
-		// Run once for package p and once for package p_test.
-		if len(p.GoFiles)+len(p.CgoFiles)+len(p.TestGoFiles) > 0 {
-			runVetFiles(p, stringList(p.GoFiles, p.CgoFiles, p.TestGoFiles, p.SFiles))
-		}
-		if len(p.XTestGoFiles) > 0 {
-			runVetFiles(p, stringList(p.XTestGoFiles))
-		}
-	}
-}
-
-func runVetFiles(p *Package, files []string) {
-	for i := range files {
-		files[i] = filepath.Join(p.Dir, files[i])
-	}
-	run(buildToolExec, tool("vet"), relPaths(files))
-}
diff --git a/libgo/go/cmd/gofmt/doc.go b/libgo/go/cmd/gofmt/doc.go
index 8b22f03..e340665 100644
--- a/libgo/go/cmd/gofmt/doc.go
+++ b/libgo/go/cmd/gofmt/doc.go
@@ -4,7 +4,8 @@
 
 /*
 Gofmt formats Go programs.
-It uses tabs (width = 8) for indentation and blanks for alignment.
+It uses tabs for indentation and blanks for alignment.
+Alignment assumes that an editor is using a fixed-width font.
 
 Without an explicit path, it processes the standard input.  Given a file,
 it operates on that file; given a directory, it operates on all .go files in
@@ -100,4 +101,4 @@
 
 // BUG(rsc): The implementation of -r is a bit slow.
 // BUG(gri): If -w fails, the restored original file may not have some of the
-//           original file attributes.
+// original file attributes.
diff --git a/libgo/go/cmd/gofmt/gofmt.go b/libgo/go/cmd/gofmt/gofmt.go
index e1ef0dd..d5b7be3 100644
--- a/libgo/go/cmd/gofmt/gofmt.go
+++ b/libgo/go/cmd/gofmt/gofmt.go
@@ -139,11 +139,11 @@
 			}
 		}
 		if *doDiff {
-			data, err := diff(src, res)
+			data, err := diff(src, res, filename)
 			if err != nil {
 				return fmt.Errorf("computing diff: %s", err)
 			}
-			fmt.Printf("diff %s gofmt/%s\n", filename, filename)
+			fmt.Printf("diff -u %s %s\n", filepath.ToSlash(filename+".orig"), filepath.ToSlash(filename))
 			out.Write(data)
 		}
 	}
@@ -225,32 +225,76 @@
 	}
 }
 
-func diff(b1, b2 []byte) (data []byte, err error) {
-	f1, err := ioutil.TempFile("", "gofmt")
+func writeTempFile(dir, prefix string, data []byte) (string, error) {
+	file, err := ioutil.TempFile(dir, prefix)
+	if err != nil {
+		return "", err
+	}
+	_, err = file.Write(data)
+	if err1 := file.Close(); err == nil {
+		err = err1
+	}
+	if err != nil {
+		os.Remove(file.Name())
+		return "", err
+	}
+	return file.Name(), nil
+}
+
+func diff(b1, b2 []byte, filename string) (data []byte, err error) {
+	f1, err := writeTempFile("", "gofmt", b1)
 	if err != nil {
 		return
 	}
-	defer os.Remove(f1.Name())
-	defer f1.Close()
+	defer os.Remove(f1)
 
-	f2, err := ioutil.TempFile("", "gofmt")
+	f2, err := writeTempFile("", "gofmt", b2)
 	if err != nil {
 		return
 	}
-	defer os.Remove(f2.Name())
-	defer f2.Close()
+	defer os.Remove(f2)
 
-	f1.Write(b1)
-	f2.Write(b2)
+	cmd := "diff"
+	if runtime.GOOS == "plan9" {
+		cmd = "/bin/ape/diff"
+	}
 
-	data, err = exec.Command("diff", "-u", f1.Name(), f2.Name()).CombinedOutput()
+	data, err = exec.Command(cmd, "-u", f1, f2).CombinedOutput()
 	if len(data) > 0 {
 		// diff exits with a non-zero status when the files don't match.
 		// Ignore that failure as long as we get output.
-		err = nil
+		return replaceTempFilename(data, filename)
 	}
 	return
+}
 
+// replaceTempFilename replaces temporary filenames in diff with actual one.
+//
+// --- /tmp/gofmt316145376	2017-02-03 19:13:00.280468375 -0500
+// +++ /tmp/gofmt617882815	2017-02-03 19:13:00.280468375 -0500
+// ...
+// ->
+// --- path/to/file.go.orig	2017-02-03 19:13:00.280468375 -0500
+// +++ path/to/file.go	2017-02-03 19:13:00.280468375 -0500
+// ...
+func replaceTempFilename(diff []byte, filename string) ([]byte, error) {
+	bs := bytes.SplitN(diff, []byte{'\n'}, 3)
+	if len(bs) < 3 {
+		return nil, fmt.Errorf("got unexpected diff for %s", filename)
+	}
+	// Preserve timestamps.
+	var t0, t1 []byte
+	if i := bytes.LastIndexByte(bs[0], '\t'); i != -1 {
+		t0 = bs[0][i:]
+	}
+	if i := bytes.LastIndexByte(bs[1], '\t'); i != -1 {
+		t1 = bs[1][i:]
+	}
+	// Always print filepath with slash separator.
+	f := filepath.ToSlash(filename)
+	bs[0] = []byte(fmt.Sprintf("--- %s%s", f+".orig", t0))
+	bs[1] = []byte(fmt.Sprintf("+++ %s%s", f, t1))
+	return bytes.Join(bs, []byte{'\n'}), nil
 }
 
 const chmodSupported = runtime.GOOS != "windows"
diff --git a/libgo/go/cmd/gofmt/gofmt_test.go b/libgo/go/cmd/gofmt/gofmt_test.go
index b7ca9e8..16b653b 100644
--- a/libgo/go/cmd/gofmt/gofmt_test.go
+++ b/libgo/go/cmd/gofmt/gofmt_test.go
@@ -9,7 +9,9 @@
 	"flag"
 	"io/ioutil"
 	"os"
+	"os/exec"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"testing"
 	"text/scanner"
@@ -110,7 +112,7 @@
 		}
 
 		t.Errorf("(gofmt %s) != %s (see %s.gofmt)", in, out, in)
-		d, err := diff(expected, got)
+		d, err := diff(expected, got, in)
 		if err == nil {
 			t.Errorf("%s", d)
 		}
@@ -184,3 +186,69 @@
 	}
 	t.Logf("Created: %s", name)
 }
+
+func TestDiff(t *testing.T) {
+	if _, err := exec.LookPath("diff"); err != nil {
+		t.Skipf("skip test on %s: diff command is required", runtime.GOOS)
+	}
+	in := []byte("first\nsecond\n")
+	out := []byte("first\nthird\n")
+	filename := "difftest.txt"
+	b, err := diff(in, out, filename)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if runtime.GOOS == "windows" {
+		b = bytes.Replace(b, []byte{'\r', '\n'}, []byte{'\n'}, -1)
+	}
+
+	bs := bytes.SplitN(b, []byte{'\n'}, 3)
+	line0, line1 := bs[0], bs[1]
+
+	if prefix := "--- difftest.txt.orig"; !bytes.HasPrefix(line0, []byte(prefix)) {
+		t.Errorf("diff: first line should start with `%s`\ngot: %s", prefix, line0)
+	}
+
+	if prefix := "+++ difftest.txt"; !bytes.HasPrefix(line1, []byte(prefix)) {
+		t.Errorf("diff: second line should start with `%s`\ngot: %s", prefix, line1)
+	}
+
+	want := `@@ -1,2 +1,2 @@
+ first
+-second
++third
+`
+
+	if got := string(bs[2]); got != want {
+		t.Errorf("diff: got:\n%s\nwant:\n%s", got, want)
+	}
+}
+
+func TestReplaceTempFilename(t *testing.T) {
+	diff := []byte(`--- /tmp/tmpfile1	2017-02-08 00:53:26.175105619 +0900
++++ /tmp/tmpfile2	2017-02-08 00:53:38.415151275 +0900
+@@ -1,2 +1,2 @@
+ first
+-second
++third
+`)
+	want := []byte(`--- path/to/file.go.orig	2017-02-08 00:53:26.175105619 +0900
++++ path/to/file.go	2017-02-08 00:53:38.415151275 +0900
+@@ -1,2 +1,2 @@
+ first
+-second
++third
+`)
+	// Check path in diff output is always slash regardless of the
+	// os.PathSeparator (`/` or `\`).
+	sep := string(os.PathSeparator)
+	filename := strings.Join([]string{"path", "to", "file.go"}, sep)
+	got, err := replaceTempFilename(diff, filename)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(got, want) {
+		t.Errorf("os.PathSeparator='%s': replacedDiff:\ngot:\n%s\nwant:\n%s", sep, got, want)
+	}
+}
diff --git a/libgo/go/cmd/gofmt/rewrite.go b/libgo/go/cmd/gofmt/rewrite.go
index 550492b..79b7858 100644
--- a/libgo/go/cmd/gofmt/rewrite.go
+++ b/libgo/go/cmd/gofmt/rewrite.go
@@ -66,10 +66,10 @@
 		if !val.IsValid() {
 			return reflect.Value{}
 		}
+		val = apply(rewriteVal, val)
 		for k := range m {
 			delete(m, k)
 		}
-		val = apply(rewriteVal, val)
 		if match(m, pat, val) {
 			val = subst(m, repl, reflect.ValueOf(val.Interface().(ast.Node).Pos()))
 		}
diff --git a/libgo/go/cmd/internal/browser/browser.go b/libgo/go/cmd/internal/browser/browser.go
index 897086f..6867c85 100644
--- a/libgo/go/cmd/internal/browser/browser.go
+++ b/libgo/go/cmd/internal/browser/browser.go
@@ -9,6 +9,7 @@
 	"os"
 	"os/exec"
 	"runtime"
+	"time"
 )
 
 // Commands returns a list of possible commands to use to open a url.
@@ -23,7 +24,10 @@
 	case "windows":
 		cmds = append(cmds, []string{"cmd", "/c", "start"})
 	default:
-		cmds = append(cmds, []string{"xdg-open"})
+		if os.Getenv("DISPLAY") != "" {
+			// xdg-open is only for use in a desktop environment.
+			cmds = append(cmds, []string{"xdg-open"})
+		}
 	}
 	cmds = append(cmds,
 		[]string{"chrome"},
@@ -38,9 +42,26 @@
 func Open(url string) bool {
 	for _, args := range Commands() {
 		cmd := exec.Command(args[0], append(args[1:], url)...)
-		if cmd.Start() == nil {
+		if cmd.Start() == nil && appearsSuccessful(cmd, 3*time.Second) {
 			return true
 		}
 	}
 	return false
 }
+
+// appearsSuccessful reports whether the command appears to have run successfully.
+// If the command runs longer than the timeout, it's deemed successful.
+// If the command runs within the timeout, it's deemed successful if it exited cleanly.
+func appearsSuccessful(cmd *exec.Cmd, timeout time.Duration) bool {
+	errc := make(chan error, 1)
+	go func() {
+		errc <- cmd.Wait()
+	}()
+
+	select {
+	case <-time.After(timeout):
+		return true
+	case err := <-errc:
+		return err == nil
+	}
+}
diff --git a/libgo/go/cmd/internal/objabi/autotype.go b/libgo/go/cmd/internal/objabi/autotype.go
new file mode 100644
index 0000000..17c4293
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/autotype.go
@@ -0,0 +1,37 @@
+// Derived from Inferno utils/6l/l.h and related files.
+// https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6l/l.h
+//
+//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+//	Portions Copyright © 1997-1999 Vita Nuova Limited
+//	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+//	Portions Copyright © 2004,2006 Bruce Ellis
+//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+//	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+//	Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package objabi
+
+// Auto.name
+const (
+	A_AUTO = 1 + iota
+	A_PARAM
+)
diff --git a/libgo/go/cmd/internal/objabi/doc.go b/libgo/go/cmd/internal/objabi/doc.go
new file mode 100644
index 0000000..7bd5ff6
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/doc.go
@@ -0,0 +1,120 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// NOTE: There are *three* independent implementations of this object
+// file format in the Go source tree:
+//
+//	- cmd/internal/goobj/read.go (used by cmd/addr2line, cmd/nm, cmd/objdump, cmd/pprof)
+//	- cmd/internal/obj/objfile.go (used by cmd/asm and cmd/compile)
+//	- cmd/link/internal/objfile.go (used by cmd/link)
+//
+// When changing the object file format, remember to change all three.
+
+// Originally, Go object files were Plan 9 object files, but no longer.
+// Now they are more like standard object files, in that each symbol is defined
+// by an associated memory image (bytes) and a list of relocations to apply
+// during linking. We do not (yet?) use a standard file format, however.
+// For now, the format is chosen to be as simple as possible to read and write.
+// It may change for reasons of efficiency, or we may even switch to a
+// standard file format if there are compelling benefits to doing so.
+// See golang.org/s/go13linker for more background.
+//
+// The file format is:
+//
+//	- magic header: "\x00\x00go19ld"
+//	- byte 1 - version number
+//	- sequence of strings giving dependencies (imported packages)
+//	- empty string (marks end of sequence)
+//	- sequence of symbol references used by the defined symbols
+//	- byte 0xff (marks end of sequence)
+//	- sequence of integer lengths:
+//		- total data length
+//		- total number of relocations
+//		- total number of pcdata
+//		- total number of automatics
+//		- total number of funcdata
+//		- total number of files
+//	- data, the content of the defined symbols
+//	- sequence of defined symbols
+//	- byte 0xff (marks end of sequence)
+//	- magic footer: "\xff\xffgo19ld"
+//
+// All integers are stored in a zigzag varint format.
+// See golang.org/s/go12symtab for a definition.
+//
+// Data blocks and strings are both stored as an integer
+// followed by that many bytes.
+//
+// A symbol reference is a string name followed by a version.
+//
+// A symbol points to other symbols using an index into the symbol
+// reference sequence. Index 0 corresponds to a nil symbol pointer.
+// In the symbol layout described below "symref index" stands for this
+// index.
+//
+// Each symbol is laid out as the following fields:
+//
+//	- byte 0xfe (sanity check for synchronization)
+//	- type [byte]
+//	- name & version [symref index]
+//	- flags [int]
+//		1<<0 dupok
+//		1<<1 local
+//		1<<2 add to typelink table
+//	- size [int]
+//	- gotype [symref index]
+//	- p [data block]
+//	- nr [int]
+//	- r [nr relocations, sorted by off]
+//
+// If type == STEXT, there are a few more fields:
+//
+//	- args [int]
+//	- locals [int]
+//	- nosplit [int]
+//	- flags [int]
+//		1<<0 leaf
+//		1<<1 C function
+//		1<<2 function may call reflect.Type.Method
+//		1<<3 function compiled with -shared
+//	- nlocal [int]
+//	- local [nlocal automatics]
+//	- pcln [pcln table]
+//
+// Each relocation has the encoding:
+//
+//	- off [int]
+//	- siz [int]
+//	- type [int]
+//	- add [int]
+//	- sym [symref index]
+//
+// Each local has the encoding:
+//
+//	- asym [symref index]
+//	- offset [int]
+//	- type [int]
+//	- gotype [symref index]
+//
+// The pcln table has the encoding:
+//
+//	- pcsp [data block]
+//	- pcfile [data block]
+//	- pcline [data block]
+//	- pcinline [data block]
+//	- npcdata [int]
+//	- pcdata [npcdata data blocks]
+//	- nfuncdata [int]
+//	- funcdata [nfuncdata symref index]
+//	- funcdatasym [nfuncdata ints]
+//	- nfile [int]
+//	- file [nfile symref index]
+//	- ninlinedcall [int]
+//	- inlinedcall [ninlinedcall int symref int symref]
+//
+// The file layout and meaning of type integers are architecture-independent.
+//
+// TODO(rsc): The file format is good for a first pass but needs work.
+//	- There are SymID in the object file that should really just be strings.
+package objabi
diff --git a/libgo/go/cmd/internal/objabi/flag.go b/libgo/go/cmd/internal/objabi/flag.go
new file mode 100644
index 0000000..e349b41
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/flag.go
@@ -0,0 +1,115 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"strconv"
+)
+
+func Flagfn2(string, string, func(string, string)) { panic("flag") }
+
+func Flagcount(name, usage string, val *int) {
+	flag.Var((*count)(val), name, usage)
+}
+
+func Flagint32(name, usage string, val *int32) {
+	flag.Var((*int32Value)(val), name, usage)
+}
+
+func Flagint64(name, usage string, val *int64) {
+	flag.Int64Var(val, name, *val, usage)
+}
+
+func Flagstr(name, usage string, val *string) {
+	flag.StringVar(val, name, *val, usage)
+}
+
+func Flagfn0(name, usage string, f func()) {
+	flag.Var(fn0(f), name, usage)
+}
+
+func Flagfn1(name, usage string, f func(string)) {
+	flag.Var(fn1(f), name, usage)
+}
+
+func Flagprint(fd int) {
+	if fd == 1 {
+		flag.CommandLine.SetOutput(os.Stdout)
+	}
+	flag.PrintDefaults()
+}
+
+func Flagparse(usage func()) {
+	flag.Usage = usage
+	flag.Parse()
+}
+
+// count is a flag.Value that is like a flag.Bool and a flag.Int.
+// If used as -name, it increments the count, but -name=x sets the count.
+// Used for verbose flag -v.
+type count int
+
+func (c *count) String() string {
+	return fmt.Sprint(int(*c))
+}
+
+func (c *count) Set(s string) error {
+	switch s {
+	case "true":
+		*c++
+	case "false":
+		*c = 0
+	default:
+		n, err := strconv.Atoi(s)
+		if err != nil {
+			return fmt.Errorf("invalid count %q", s)
+		}
+		*c = count(n)
+	}
+	return nil
+}
+
+func (c *count) IsBoolFlag() bool {
+	return true
+}
+
+type int32Value int32
+
+func (i *int32Value) Set(s string) error {
+	v, err := strconv.ParseInt(s, 0, 64)
+	*i = int32Value(v)
+	return err
+}
+
+func (i *int32Value) Get() interface{} { return int32(*i) }
+
+func (i *int32Value) String() string { return fmt.Sprint(*i) }
+
+type fn0 func()
+
+func (f fn0) Set(s string) error {
+	f()
+	return nil
+}
+
+func (f fn0) Get() interface{} { return nil }
+
+func (f fn0) String() string { return "" }
+
+func (f fn0) IsBoolFlag() bool {
+	return true
+}
+
+type fn1 func(string)
+
+func (f fn1) Set(s string) error {
+	f(s)
+	return nil
+}
+
+func (f fn1) String() string { return "" }
diff --git a/libgo/go/cmd/internal/objabi/funcdata.go b/libgo/go/cmd/internal/objabi/funcdata.go
new file mode 100644
index 0000000..80874ed
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/funcdata.go
@@ -0,0 +1,25 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+// This file defines the IDs for PCDATA and FUNCDATA instructions
+// in Go binaries.
+//
+// These must agree with ../../../runtime/funcdata.h and
+// ../../../runtime/symtab.go.
+
+const (
+	PCDATA_StackMapIndex       = 0
+	PCDATA_InlTreeIndex        = 1
+	FUNCDATA_ArgsPointerMaps   = 0
+	FUNCDATA_LocalsPointerMaps = 1
+	FUNCDATA_InlTree           = 2
+
+	// ArgsSizeUnknown is set in Func.argsize to mark all functions
+	// whose argument size is unknown (C vararg functions, and
+	// assembly code without an explicit specification).
+	// This value is generated by the compiler, assembler, or linker.
+	ArgsSizeUnknown = -0x80000000
+)
diff --git a/libgo/go/cmd/internal/objabi/head.go b/libgo/go/cmd/internal/objabi/head.go
new file mode 100644
index 0000000..ff19606
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/head.go
@@ -0,0 +1,104 @@
+// Derived from Inferno utils/6l/l.h and related files.
+// https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6l/l.h
+//
+//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+//	Portions Copyright © 1997-1999 Vita Nuova Limited
+//	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+//	Portions Copyright © 2004,2006 Bruce Ellis
+//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+//	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+//	Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package objabi
+
+import "fmt"
+
+// HeadType is the executable header type.
+type HeadType uint8
+
+const (
+	Hunknown HeadType = iota
+	Hdarwin
+	Hdragonfly
+	Hfreebsd
+	Hlinux
+	Hnacl
+	Hnetbsd
+	Hopenbsd
+	Hplan9
+	Hsolaris
+	Hwindows
+)
+
+func (h *HeadType) Set(s string) error {
+	switch s {
+	case "darwin":
+		*h = Hdarwin
+	case "dragonfly":
+		*h = Hdragonfly
+	case "freebsd":
+		*h = Hfreebsd
+	case "linux", "android":
+		*h = Hlinux
+	case "nacl":
+		*h = Hnacl
+	case "netbsd":
+		*h = Hnetbsd
+	case "openbsd":
+		*h = Hopenbsd
+	case "plan9":
+		*h = Hplan9
+	case "solaris":
+		*h = Hsolaris
+	case "windows":
+		*h = Hwindows
+	default:
+		return fmt.Errorf("invalid headtype: %q", s)
+	}
+	return nil
+}
+
+func (h *HeadType) String() string {
+	switch *h {
+	case Hdarwin:
+		return "darwin"
+	case Hdragonfly:
+		return "dragonfly"
+	case Hfreebsd:
+		return "freebsd"
+	case Hlinux:
+		return "linux"
+	case Hnacl:
+		return "nacl"
+	case Hnetbsd:
+		return "netbsd"
+	case Hopenbsd:
+		return "openbsd"
+	case Hplan9:
+		return "plan9"
+	case Hsolaris:
+		return "solaris"
+	case Hwindows:
+		return "windows"
+	}
+	return fmt.Sprintf("HeadType(%d)", *h)
+}
diff --git a/libgo/go/cmd/internal/objabi/line.go b/libgo/go/cmd/internal/objabi/line.go
new file mode 100644
index 0000000..ed509b7
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/line.go
@@ -0,0 +1,82 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+import (
+	"os"
+	"path/filepath"
+)
+
+// WorkingDir returns the current working directory
+// (or "/???" if the directory cannot be identified),
+// with "/" as separator.
+func WorkingDir() string {
+	var path string
+	path, _ = os.Getwd()
+	if path == "" {
+		path = "/???"
+	}
+	return filepath.ToSlash(path)
+}
+
+// AbsFile returns the absolute filename for file in the given directory.
+// It also removes a leading pathPrefix, or else rewrites a leading $GOROOT
+// prefix to the literal "$GOROOT".
+// If the resulting path is the empty string, the result is "??".
+func AbsFile(dir, file, pathPrefix string) string {
+	abs := file
+	if dir != "" && !filepath.IsAbs(file) {
+		abs = filepath.Join(dir, file)
+	}
+
+	if pathPrefix != "" && hasPathPrefix(abs, pathPrefix) {
+		if abs == pathPrefix {
+			abs = ""
+		} else {
+			abs = abs[len(pathPrefix)+1:]
+		}
+	} else if hasPathPrefix(abs, GOROOT) {
+		abs = "$GOROOT" + abs[len(GOROOT):]
+	}
+	if abs == "" {
+		abs = "??"
+	}
+
+	return filepath.Clean(abs)
+}
+
+// Does s have t as a path prefix?
+// That is, does s == t or does s begin with t followed by a slash?
+// For portability, we allow ASCII case folding, so that hasPathPrefix("a/b/c", "A/B") is true.
+// Similarly, we allow slash folding, so that hasPathPrefix("a/b/c", "a\\b") is true.
+// We do not allow full Unicode case folding, for fear of causing more confusion
+// or harm than good. (For an example of the kinds of things that can go wrong,
+// see http://article.gmane.org/gmane.linux.kernel/1853266.)
+func hasPathPrefix(s string, t string) bool {
+	if len(t) > len(s) {
+		return false
+	}
+	var i int
+	for i = 0; i < len(t); i++ {
+		cs := int(s[i])
+		ct := int(t[i])
+		if 'A' <= cs && cs <= 'Z' {
+			cs += 'a' - 'A'
+		}
+		if 'A' <= ct && ct <= 'Z' {
+			ct += 'a' - 'A'
+		}
+		if cs == '\\' {
+			cs = '/'
+		}
+		if ct == '\\' {
+			ct = '/'
+		}
+		if cs != ct {
+			return false
+		}
+	}
+	return i >= len(s) || s[i] == '/' || s[i] == '\\'
+}
diff --git a/libgo/go/cmd/internal/objabi/path.go b/libgo/go/cmd/internal/objabi/path.go
new file mode 100644
index 0000000..2a42179
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/path.go
@@ -0,0 +1,41 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+import "strings"
+
+// PathToPrefix converts raw string to the prefix that will be used in the
+// symbol table. All control characters, space, '%' and '"', as well as
+// non-7-bit clean bytes turn into %xx. The period needs escaping only in the
+// last segment of the path, and it makes for happier users if we escape that as
+// little as possible.
+func PathToPrefix(s string) string {
+	slash := strings.LastIndex(s, "/")
+	// check for chars that need escaping
+	n := 0
+	for r := 0; r < len(s); r++ {
+		if c := s[r]; c <= ' ' || (c == '.' && r > slash) || c == '%' || c == '"' || c >= 0x7F {
+			n++
+		}
+	}
+
+	// quick exit
+	if n == 0 {
+		return s
+	}
+
+	// escape
+	const hex = "0123456789abcdef"
+	p := make([]byte, 0, len(s)+2*n)
+	for r := 0; r < len(s); r++ {
+		if c := s[r]; c <= ' ' || (c == '.' && r > slash) || c == '%' || c == '"' || c >= 0x7F {
+			p = append(p, '%', hex[c>>4], hex[c&0xF])
+		} else {
+			p = append(p, c)
+		}
+	}
+
+	return string(p)
+}
diff --git a/libgo/go/cmd/internal/objabi/path_test.go b/libgo/go/cmd/internal/objabi/path_test.go
new file mode 100644
index 0000000..05d7fb4
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/path_test.go
@@ -0,0 +1,33 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+import "testing"
+
+func TestPathToPrefix(t *testing.T) {
+	tests := []struct {
+		Path     string
+		Expected string
+	}{{"foo/bar/v1", "foo/bar/v1"},
+		{"foo/bar/v.1", "foo/bar/v%2e1"},
+		{"f.o.o/b.a.r/v1", "f.o.o/b.a.r/v1"},
+		{"f.o.o/b.a.r/v.1", "f.o.o/b.a.r/v%2e1"},
+		{"f.o.o/b.a.r/v..1", "f.o.o/b.a.r/v%2e%2e1"},
+		{"f.o.o/b.a.r/v..1.", "f.o.o/b.a.r/v%2e%2e1%2e"},
+		{"f.o.o/b.a.r/v%1", "f.o.o/b.a.r/v%251"},
+		{"runtime", "runtime"},
+		{"sync/atomic", "sync/atomic"},
+		{"golang.org/x/tools/godoc", "golang.org/x/tools/godoc"},
+		{"foo.bar/baz.quux", "foo.bar/baz%2equux"},
+		{"", ""},
+		{"%foo%bar", "%25foo%25bar"},
+		{"\x01\x00\x7F☺", "%01%00%7f%e2%98%ba"},
+	}
+	for _, tc := range tests {
+		if got := PathToPrefix(tc.Path); got != tc.Expected {
+			t.Errorf("expected PathToPrefix(%s) = %s, got %s", tc.Path, tc.Expected, got)
+		}
+	}
+}
diff --git a/libgo/go/cmd/internal/objabi/reloctype.go b/libgo/go/cmd/internal/objabi/reloctype.go
new file mode 100644
index 0000000..179f049
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/reloctype.go
@@ -0,0 +1,200 @@
+// Derived from Inferno utils/6l/l.h and related files.
+// https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6l/l.h
+//
+//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+//	Portions Copyright © 1997-1999 Vita Nuova Limited
+//	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+//	Portions Copyright © 2004,2006 Bruce Ellis
+//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+//	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+//	Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package objabi
+
+type RelocType int32
+
+//go:generate stringer -type=RelocType
+const (
+	R_ADDR RelocType = 1 + iota
+	// R_ADDRPOWER relocates a pair of "D-form" instructions (instructions with 16-bit
+	// immediates in the low half of the instruction word), usually addis followed by
+	// another add or a load, inserting the "high adjusted" 16 bits of the address of
+	// the referenced symbol into the immediate field of the first instruction and the
+	// low 16 bits into that of the second instruction.
+	R_ADDRPOWER
+	// R_ADDRARM64 relocates an adrp, add pair to compute the address of the
+	// referenced symbol.
+	R_ADDRARM64
+	// R_ADDRMIPS (only used on mips/mips64) resolves to the low 16 bits of an external
+	// address, by encoding it into the instruction.
+	R_ADDRMIPS
+	// R_ADDROFF resolves to a 32-bit offset from the beginning of the section
+	// holding the data being relocated to the referenced symbol.
+	R_ADDROFF
+	// R_WEAKADDROFF resolves just like R_ADDROFF but is a weak relocation.
+	// A weak relocation does not make the symbol it refers to reachable,
+	// and is only honored by the linker if the symbol is in some other way
+	// reachable.
+	R_WEAKADDROFF
+	R_SIZE
+	R_CALL
+	R_CALLARM
+	R_CALLARM64
+	R_CALLIND
+	R_CALLPOWER
+	// R_CALLMIPS (only used on mips64) resolves to non-PC-relative target address
+	// of a CALL (JAL) instruction, by encoding the address into the instruction.
+	R_CALLMIPS
+	R_CONST
+	R_PCREL
+	// R_TLS_LE, used on 386, amd64, and ARM, resolves to the offset of the
+	// thread-local symbol from the thread local base and is used to implement the
+	// "local exec" model for tls access (r.Sym is not set on intel platforms but is
+	// set to a TLS symbol -- runtime.tlsg -- in the linker when externally linking).
+	R_TLS_LE
+	// R_TLS_IE, used 386, amd64, and ARM resolves to the PC-relative offset to a GOT
+	// slot containing the offset from the thread-local symbol from the thread local
+	// base and is used to implemented the "initial exec" model for tls access (r.Sym
+	// is not set on intel platforms but is set to a TLS symbol -- runtime.tlsg -- in
+	// the linker when externally linking).
+	R_TLS_IE
+	R_GOTOFF
+	R_PLT0
+	R_PLT1
+	R_PLT2
+	R_USEFIELD
+	// R_USETYPE resolves to an *rtype, but no relocation is created. The
+	// linker uses this as a signal that the pointed-to type information
+	// should be linked into the final binary, even if there are no other
+	// direct references. (This is used for types reachable by reflection.)
+	R_USETYPE
+	// R_METHODOFF resolves to a 32-bit offset from the beginning of the section
+	// holding the data being relocated to the referenced symbol.
+	// It is a variant of R_ADDROFF used when linking from the uncommonType of a
+	// *rtype, and may be set to zero by the linker if it determines the method
+	// text is unreachable by the linked program.
+	R_METHODOFF
+	R_POWER_TOC
+	R_GOTPCREL
+	// R_JMPMIPS (only used on mips64) resolves to non-PC-relative target address
+	// of a JMP instruction, by encoding the address into the instruction.
+	// The stack nosplit check ignores this since it is not a function call.
+	R_JMPMIPS
+	// R_DWARFREF resolves to the offset of the symbol from its section.
+	R_DWARFREF
+
+	// Platform dependent relocations. Architectures with fixed width instructions
+	// have the inherent issue that a 32-bit (or 64-bit!) displacement cannot be
+	// stuffed into a 32-bit instruction, so an address needs to be spread across
+	// several instructions, and in turn this requires a sequence of relocations, each
+	// updating a part of an instruction. This leads to relocation codes that are
+	// inherently processor specific.
+
+	// Arm64.
+
+	// Set a MOV[NZ] immediate field to bits [15:0] of the offset from the thread
+	// local base to the thread local variable defined by the referenced (thread
+	// local) symbol. Error if the offset does not fit into 16 bits.
+	R_ARM64_TLS_LE
+
+	// Relocates an ADRP; LD64 instruction sequence to load the offset between
+	// the thread local base and the thread local variable defined by the
+	// referenced (thread local) symbol from the GOT.
+	R_ARM64_TLS_IE
+
+	// R_ARM64_GOTPCREL relocates an adrp, ld64 pair to compute the address of the GOT
+	// slot of the referenced symbol.
+	R_ARM64_GOTPCREL
+
+	// PPC64.
+
+	// R_POWER_TLS_LE is used to implement the "local exec" model for tls
+	// access. It resolves to the offset of the thread-local symbol from the
+	// thread pointer (R13) and inserts this value into the low 16 bits of an
+	// instruction word.
+	R_POWER_TLS_LE
+
+	// R_POWER_TLS_IE is used to implement the "initial exec" model for tls access. It
+	// relocates a D-form, DS-form instruction sequence like R_ADDRPOWER_DS. It
+	// inserts to the offset of GOT slot for the thread-local symbol from the TOC (the
+	// GOT slot is filled by the dynamic linker with the offset of the thread-local
+	// symbol from the thread pointer (R13)).
+	R_POWER_TLS_IE
+
+	// R_POWER_TLS marks an X-form instruction such as "MOVD 0(R13)(R31*1), g" as
+	// accessing a particular thread-local symbol. It does not affect code generation
+	// but is used by the system linker when relaxing "initial exec" model code to
+	// "local exec" model code.
+	R_POWER_TLS
+
+	// R_ADDRPOWER_DS is similar to R_ADDRPOWER above, but assumes the second
+	// instruction is a "DS-form" instruction, which has an immediate field occupying
+	// bits [15:2] of the instruction word. Bits [15:2] of the address of the
+	// relocated symbol are inserted into this field; it is an error if the last two
+	// bits of the address are not 0.
+	R_ADDRPOWER_DS
+
+	// R_ADDRPOWER_PCREL relocates a D-form, DS-form instruction sequence like
+	// R_ADDRPOWER_DS but inserts the offset of the GOT slot for the referenced symbol
+	// from the TOC rather than the symbol's address.
+	R_ADDRPOWER_GOT
+
+	// R_ADDRPOWER_PCREL relocates two D-form instructions like R_ADDRPOWER, but
+	// inserts the displacement from the place being relocated to the address of the
+	// the relocated symbol instead of just its address.
+	R_ADDRPOWER_PCREL
+
+	// R_ADDRPOWER_TOCREL relocates two D-form instructions like R_ADDRPOWER, but
+	// inserts the offset from the TOC to the address of the relocated symbol
+	// rather than the symbol's address.
+	R_ADDRPOWER_TOCREL
+
+	// R_ADDRPOWER_TOCREL relocates a D-form, DS-form instruction sequence like
+	// R_ADDRPOWER_DS but inserts the offset from the TOC to the address of the the
+	// relocated symbol rather than the symbol's address.
+	R_ADDRPOWER_TOCREL_DS
+
+	// R_PCRELDBL relocates s390x 2-byte aligned PC-relative addresses.
+	// TODO(mundaym): remove once variants can be serialized - see issue 14218.
+	R_PCRELDBL
+
+	// R_ADDRMIPSU (only used on mips/mips64) resolves to the sign-adjusted "upper" 16
+	// bits (bit 16-31) of an external address, by encoding it into the instruction.
+	R_ADDRMIPSU
+	// R_ADDRMIPSTLS (only used on mips64) resolves to the low 16 bits of a TLS
+	// address (offset from thread pointer), by encoding it into the instruction.
+	R_ADDRMIPSTLS
+)
+
+// IsDirectJump returns whether r is a relocation for a direct jump.
+// A direct jump is a CALL or JMP instruction that takes the target address
+// as immediate. The address is embedded into the instruction, possibly
+// with limited width.
+// An indirect jump is a CALL or JMP instruction that takes the target address
+// in register or memory.
+func (r RelocType) IsDirectJump() bool {
+	switch r {
+	case R_CALL, R_CALLARM, R_CALLARM64, R_CALLPOWER, R_CALLMIPS, R_JMPMIPS:
+		return true
+	}
+	return false
+}
diff --git a/libgo/go/cmd/internal/objabi/reloctype_string.go b/libgo/go/cmd/internal/objabi/reloctype_string.go
new file mode 100644
index 0000000..182d03f
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/reloctype_string.go
@@ -0,0 +1,17 @@
+// Code generated by "stringer -type=RelocType"; DO NOT EDIT.
+
+package objabi
+
+import "fmt"
+
+const _RelocType_name = "R_ADDRR_ADDRPOWERR_ADDRARM64R_ADDRMIPSR_ADDROFFR_WEAKADDROFFR_SIZER_CALLR_CALLARMR_CALLARM64R_CALLINDR_CALLPOWERR_CALLMIPSR_CONSTR_PCRELR_TLS_LER_TLS_IER_GOTOFFR_PLT0R_PLT1R_PLT2R_USEFIELDR_USETYPER_METHODOFFR_POWER_TOCR_GOTPCRELR_JMPMIPSR_DWARFREFR_ARM64_TLS_LER_ARM64_TLS_IER_ARM64_GOTPCRELR_POWER_TLS_LER_POWER_TLS_IER_POWER_TLSR_ADDRPOWER_DSR_ADDRPOWER_GOTR_ADDRPOWER_PCRELR_ADDRPOWER_TOCRELR_ADDRPOWER_TOCREL_DSR_PCRELDBLR_ADDRMIPSUR_ADDRMIPSTLS"
+
+var _RelocType_index = [...]uint16{0, 6, 17, 28, 38, 47, 60, 66, 72, 81, 92, 101, 112, 122, 129, 136, 144, 152, 160, 166, 172, 178, 188, 197, 208, 219, 229, 238, 248, 262, 276, 292, 306, 320, 331, 345, 360, 377, 395, 416, 426, 437, 450}
+
+func (i RelocType) String() string {
+	i -= 1
+	if i < 0 || i >= RelocType(len(_RelocType_index)-1) {
+		return fmt.Sprintf("RelocType(%d)", i+1)
+	}
+	return _RelocType_name[_RelocType_index[i]:_RelocType_index[i+1]]
+}
diff --git a/libgo/go/cmd/internal/objabi/stack.go b/libgo/go/cmd/internal/objabi/stack.go
new file mode 100644
index 0000000..1143393
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/stack.go
@@ -0,0 +1,20 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+// For the linkers. Must match Go definitions.
+
+const (
+	STACKSYSTEM = 0
+	StackSystem = STACKSYSTEM
+	StackBig    = 4096
+	StackGuard  = 880*stackGuardMultiplier + StackSystem
+	StackSmall  = 128
+	StackLimit  = StackGuard - StackSystem - StackSmall
+)
+
+const (
+	StackPreempt = -1314 // 0xfff...fade
+)
diff --git a/libgo/go/cmd/internal/objabi/symkind.go b/libgo/go/cmd/internal/objabi/symkind.go
new file mode 100644
index 0000000..b037e9e
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/symkind.go
@@ -0,0 +1,60 @@
+// Derived from Inferno utils/6l/l.h and related files.
+// https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6l/l.h
+//
+//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+//	Portions Copyright © 1997-1999 Vita Nuova Limited
+//	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+//	Portions Copyright © 2004,2006 Bruce Ellis
+//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+//	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+//	Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package objabi
+
+// A SymKind describes the kind of memory represented by a symbol.
+type SymKind uint8
+
+// Defined SymKind values.
+//
+// TODO(rsc): Give idiomatic Go names.
+//go:generate stringer -type=SymKind
+const (
+	// An otherwise invalid zero value for the type
+	Sxxx SymKind = iota
+	// Executable instructions
+	STEXT
+	// Read only static data
+	SRODATA
+	// Static data that does not contain any pointers
+	SNOPTRDATA
+	// Static data
+	SDATA
+	// Statically data that is initially all 0s
+	SBSS
+	// Statically data that is initially all 0s and does not contain pointers
+	SNOPTRBSS
+	// Thread-local data that is initally all 0s
+	STLSBSS
+	// Debugging data
+	SDWARFINFO
+	SDWARFRANGE
+)
diff --git a/libgo/go/cmd/internal/objabi/symkind_string.go b/libgo/go/cmd/internal/objabi/symkind_string.go
new file mode 100644
index 0000000..5123dc7
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/symkind_string.go
@@ -0,0 +1,16 @@
+// Code generated by "stringer -type=SymKind"; DO NOT EDIT.
+
+package objabi
+
+import "fmt"
+
+const _SymKind_name = "SxxxSTEXTSRODATASNOPTRDATASDATASBSSSNOPTRBSSSTLSBSSSDWARFINFOSDWARFRANGE"
+
+var _SymKind_index = [...]uint8{0, 4, 9, 16, 26, 31, 35, 44, 51, 61, 72}
+
+func (i SymKind) String() string {
+	if i >= SymKind(len(_SymKind_index)-1) {
+		return fmt.Sprintf("SymKind(%d)", i)
+	}
+	return _SymKind_name[_SymKind_index[i]:_SymKind_index[i+1]]
+}
diff --git a/libgo/go/cmd/internal/objabi/typekind.go b/libgo/go/cmd/internal/objabi/typekind.go
new file mode 100644
index 0000000..f0e6f47
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/typekind.go
@@ -0,0 +1,41 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+// Must match runtime and reflect.
+// Included by cmd/gc.
+
+const (
+	KindBool = 1 + iota
+	KindInt
+	KindInt8
+	KindInt16
+	KindInt32
+	KindInt64
+	KindUint
+	KindUint8
+	KindUint16
+	KindUint32
+	KindUint64
+	KindUintptr
+	KindFloat32
+	KindFloat64
+	KindComplex64
+	KindComplex128
+	KindArray
+	KindChan
+	KindFunc
+	KindInterface
+	KindMap
+	KindPtr
+	KindSlice
+	KindString
+	KindStruct
+	KindUnsafePointer
+	KindDirectIface = 1 << 5
+	KindGCProg      = 1 << 6
+	KindNoPointers  = 1 << 7
+	KindMask        = (1 << 5) - 1
+)
diff --git a/libgo/go/cmd/internal/objabi/util.go b/libgo/go/cmd/internal/objabi/util.go
new file mode 100644
index 0000000..1da0502
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/util.go
@@ -0,0 +1,119 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package objabi
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strings"
+)
+
+func envOr(key, value string) string {
+	if x := os.Getenv(key); x != "" {
+		return x
+	}
+	return value
+}
+
+var (
+	GOROOT  = envOr("GOROOT", defaultGOROOT)
+	GOARCH  = envOr("GOARCH", defaultGOARCH)
+	GOOS    = envOr("GOOS", defaultGOOS)
+	GO386   = envOr("GO386", defaultGO386)
+	GOARM   = goarm()
+	Version = version
+)
+
+func goarm() int {
+	switch v := envOr("GOARM", defaultGOARM); v {
+	case "5":
+		return 5
+	case "6":
+		return 6
+	case "7":
+		return 7
+	}
+	// Fail here, rather than validate at multiple call sites.
+	log.Fatalf("Invalid GOARM value. Must be 5, 6, or 7.")
+	panic("unreachable")
+}
+
+func Getgoextlinkenabled() string {
+	return envOr("GO_EXTLINK_ENABLED", defaultGO_EXTLINK_ENABLED)
+}
+
+func init() {
+	for _, f := range strings.Split(goexperiment, ",") {
+		if f != "" {
+			addexp(f)
+		}
+	}
+}
+
+func Framepointer_enabled(goos, goarch string) bool {
+	return framepointer_enabled != 0 && goarch == "amd64" && goos != "nacl"
+}
+
+func addexp(s string) {
+	// Could do general integer parsing here, but the runtime copy doesn't yet.
+	v := 1
+	name := s
+	if len(name) > 2 && name[:2] == "no" {
+		v = 0
+		name = name[2:]
+	}
+	for i := 0; i < len(exper); i++ {
+		if exper[i].name == name {
+			if exper[i].val != nil {
+				*exper[i].val = v
+			}
+			return
+		}
+	}
+
+	fmt.Printf("unknown experiment %s\n", s)
+	os.Exit(2)
+}
+
+var (
+	framepointer_enabled     int = 1
+	Fieldtrack_enabled       int
+	Preemptibleloops_enabled int
+	Clobberdead_enabled      int
+)
+
+// Toolchain experiments.
+// These are controlled by the GOEXPERIMENT environment
+// variable recorded when the toolchain is built.
+// This list is also known to cmd/gc.
+var exper = []struct {
+	name string
+	val  *int
+}{
+	{"fieldtrack", &Fieldtrack_enabled},
+	{"framepointer", &framepointer_enabled},
+	{"preemptibleloops", &Preemptibleloops_enabled},
+	{"clobberdead", &Clobberdead_enabled},
+}
+
+var defaultExpstring = Expstring()
+
+func DefaultExpstring() string {
+	return defaultExpstring
+}
+
+func Expstring() string {
+	buf := "X"
+	for i := range exper {
+		if *exper[i].val != 0 {
+			buf += "," + exper[i].name
+		}
+	}
+	if buf == "X" {
+		buf += ",none"
+	}
+	return "X:" + buf[2:]
+}
diff --git a/libgo/go/cmd/internal/objabi/zbootstrap.go b/libgo/go/cmd/internal/objabi/zbootstrap.go
new file mode 100644
index 0000000..56450fa
--- /dev/null
+++ b/libgo/go/cmd/internal/objabi/zbootstrap.go
@@ -0,0 +1,15 @@
+// auto generated by go tool dist
+
+package objabi
+
+import "runtime"
+
+const defaultGOROOT = `/home/iant/go1.9`
+const defaultGO386 = `sse2`
+const defaultGOARM = `5`
+const defaultGOOS = runtime.GOOS
+const defaultGOARCH = runtime.GOARCH
+const defaultGO_EXTLINK_ENABLED = ``
+const version = `go1.9rc2`
+const stackGuardMultiplier = 1
+const goexperiment = ``
diff --git a/libgo/go/compress/bzip2/bzip2_test.go b/libgo/go/compress/bzip2/bzip2_test.go
index 95fb189..a6c3080 100644
--- a/libgo/go/compress/bzip2/bzip2_test.go
+++ b/libgo/go/compress/bzip2/bzip2_test.go
@@ -204,6 +204,12 @@
 	}
 }
 
+var (
+	digits = mustLoadFile("testdata/e.txt.bz2")
+	twain  = mustLoadFile("testdata/Mark.Twain-Tom.Sawyer.txt.bz2")
+	random = mustLoadFile("testdata/random.data.bz2")
+)
+
 func benchmarkDecode(b *testing.B, compressed []byte) {
 	// Determine the uncompressed size of testfile.
 	uncompressedSize, err := io.Copy(ioutil.Discard, NewReader(bytes.NewReader(compressed)))
@@ -221,18 +227,6 @@
 	}
 }
 
-func BenchmarkDecodeDigits(b *testing.B) {
-	digits := mustLoadFile("testdata/e.txt.bz2")
-	b.ResetTimer()
-	benchmarkDecode(b, digits)
-}
-func BenchmarkDecodeTwain(b *testing.B) {
-	twain := mustLoadFile("testdata/Mark.Twain-Tom.Sawyer.txt.bz2")
-	b.ResetTimer()
-	benchmarkDecode(b, twain)
-}
-func BenchmarkDecodeRand(b *testing.B) {
-	random := mustLoadFile("testdata/random.data.bz2")
-	b.ResetTimer()
-	benchmarkDecode(b, random)
-}
+func BenchmarkDecodeDigits(b *testing.B) { benchmarkDecode(b, digits) }
+func BenchmarkDecodeTwain(b *testing.B)  { benchmarkDecode(b, twain) }
+func BenchmarkDecodeRand(b *testing.B)   { benchmarkDecode(b, random) }
diff --git a/libgo/go/compress/bzip2/huffman.go b/libgo/go/compress/bzip2/huffman.go
index 9d574b9..dbba9a5 100644
--- a/libgo/go/compress/bzip2/huffman.go
+++ b/libgo/go/compress/bzip2/huffman.go
@@ -108,10 +108,6 @@
 	codes := huffmanCodes(make([]huffmanCode, len(lengths)))
 	for i := len(pairs) - 1; i >= 0; i-- {
 		if length > pairs[i].length {
-			// If the code length decreases we shift in order to
-			// zero any bits beyond the end of the code.
-			length >>= 32 - pairs[i].length
-			length <<= 32 - pairs[i].length
 			length = pairs[i].length
 		}
 		codes[i].code = code
diff --git a/libgo/go/compress/flate/huffman_code.go b/libgo/go/compress/flate/huffman_code.go
index bdcbd82..891537e 100644
--- a/libgo/go/compress/flate/huffman_code.go
+++ b/libgo/go/compress/flate/huffman_code.go
@@ -6,6 +6,7 @@
 
 import (
 	"math"
+	"math/bits"
 	"sort"
 )
 
@@ -342,3 +343,7 @@
 }
 
 func (s byFreq) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+func reverseBits(number uint16, bitLength byte) uint16 {
+	return bits.Reverse16(number << (16 - bitLength))
+}
diff --git a/libgo/go/compress/flate/inflate.go b/libgo/go/compress/flate/inflate.go
index 9a8c4fc..faa33cc 100644
--- a/libgo/go/compress/flate/inflate.go
+++ b/libgo/go/compress/flate/inflate.go
@@ -10,6 +10,7 @@
 import (
 	"bufio"
 	"io"
+	mathbits "math/bits"
 	"strconv"
 	"sync"
 )
@@ -176,7 +177,7 @@
 		link := nextcode[huffmanChunkBits+1] >> 1
 		h.links = make([][]uint32, huffmanNumChunks-link)
 		for j := uint(link); j < huffmanNumChunks; j++ {
-			reverse := int(reverseByte[j>>8]) | int(reverseByte[j&0xff])<<8
+			reverse := int(mathbits.Reverse16(uint16(j)))
 			reverse >>= uint(16 - huffmanChunkBits)
 			off := j - uint(link)
 			if sanity && h.chunks[reverse] != 0 {
@@ -194,7 +195,7 @@
 		code := nextcode[n]
 		nextcode[n]++
 		chunk := uint32(i<<huffmanValueShift | n)
-		reverse := int(reverseByte[code>>8]) | int(reverseByte[code&0xff])<<8
+		reverse := int(mathbits.Reverse16(uint16(code)))
 		reverse >>= uint(16 - n)
 		if n <= huffmanChunkBits {
 			for off := reverse; off < len(h.chunks); off += 1 << uint(n) {
@@ -556,7 +557,7 @@
 					return
 				}
 			}
-			dist = int(reverseByte[(f.b&0x1F)<<3])
+			dist = int(mathbits.Reverse8(uint8(f.b & 0x1F << 3)))
 			f.b >>= 5
 			f.nb -= 5
 		} else {
diff --git a/libgo/go/compress/flate/reverse_bits.go b/libgo/go/compress/flate/reverse_bits.go
deleted file mode 100644
index 6b22290..0000000
--- a/libgo/go/compress/flate/reverse_bits.go
+++ /dev/null
@@ -1,48 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package flate
-
-var reverseByte = [256]byte{
-	0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
-	0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
-	0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
-	0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
-	0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
-	0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
-	0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
-	0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
-	0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
-	0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
-	0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
-	0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
-	0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
-	0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
-	0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
-	0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
-	0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
-	0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
-	0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
-	0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
-	0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
-	0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
-	0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
-	0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
-	0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
-	0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
-	0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
-	0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
-	0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
-	0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
-	0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
-	0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
-}
-
-func reverseUint16(v uint16) uint16 {
-	return uint16(reverseByte[v>>8]) | uint16(reverseByte[v&0xFF])<<8
-}
-
-func reverseBits(number uint16, bitLength byte) uint16 {
-	return reverseUint16(number << (16 - bitLength))
-}
diff --git a/libgo/go/compress/gzip/gzip.go b/libgo/go/compress/gzip/gzip.go
index aafb442..0cc44c5 100644
--- a/libgo/go/compress/gzip/gzip.go
+++ b/libgo/go/compress/gzip/gzip.go
@@ -222,8 +222,9 @@
 	return z.err
 }
 
-// Close closes the Writer, flushing any unwritten data to the underlying
-// io.Writer, but does not close the underlying io.Writer.
+// Close closes the Writer by flushing any unwritten data to the underlying
+// io.Writer and writing the GZIP footer.
+// It does not close the underlying io.Writer.
 func (z *Writer) Close() error {
 	if z.err != nil {
 		return z.err
diff --git a/libgo/go/compress/lzw/reader.go b/libgo/go/compress/lzw/reader.go
index 9eef2b2..1be52d5 100644
--- a/libgo/go/compress/lzw/reader.go
+++ b/libgo/go/compress/lzw/reader.go
@@ -57,8 +57,14 @@
 	// The next two codes mean clear and EOF.
 	// Other valid codes are in the range [lo, hi] where lo := clear + 2,
 	// with the upper bound incrementing on each code seen.
-	// overflow is the code at which hi overflows the code width.
+	//
+	// overflow is the code at which hi overflows the code width. It always
+	// equals 1 << width.
+	//
 	// last is the most recently seen code, or decoderInvalidCode.
+	//
+	// An invariant is that
+	// (hi < overflow) || (hi == overflow && last == decoderInvalidCode)
 	clear, eof, hi, overflow, last uint16
 
 	// Each code c in [lo, hi] expands to two or more bytes. For c != hi:
@@ -163,7 +169,7 @@
 			break loop
 		case code <= d.hi:
 			c, i := code, len(d.output)-1
-			if code == d.hi {
+			if code == d.hi && d.last != decoderInvalidCode {
 				// code == hi is a special case which expands to the last expansion
 				// followed by the head of the last expansion. To find the head, we walk
 				// the prefix chain until we find a literal code.
@@ -196,6 +202,10 @@
 		if d.hi >= d.overflow {
 			if d.width == maxWidth {
 				d.last = decoderInvalidCode
+				// Undo the d.hi++ a few lines above, so that (1) we maintain
+				// the invariant that d.hi <= d.overflow, and (2) d.hi does not
+				// eventually overflow a uint16.
+				d.hi--
 			} else {
 				d.width++
 				d.overflow <<= 1
diff --git a/libgo/go/compress/lzw/reader_test.go b/libgo/go/compress/lzw/reader_test.go
index 6b9f9a3..f8974de 100644
--- a/libgo/go/compress/lzw/reader_test.go
+++ b/libgo/go/compress/lzw/reader_test.go
@@ -120,6 +120,103 @@
 	}
 }
 
+type devZero struct{}
+
+func (devZero) Read(p []byte) (int, error) {
+	for i := range p {
+		p[i] = 0
+	}
+	return len(p), nil
+}
+
+func TestHiCodeDoesNotOverflow(t *testing.T) {
+	r := NewReader(devZero{}, LSB, 8)
+	d := r.(*decoder)
+	buf := make([]byte, 1024)
+	oldHi := uint16(0)
+	for i := 0; i < 100; i++ {
+		if _, err := io.ReadFull(r, buf); err != nil {
+			t.Fatalf("i=%d: %v", i, err)
+		}
+		// The hi code should never decrease.
+		if d.hi < oldHi {
+			t.Fatalf("i=%d: hi=%d decreased from previous value %d", i, d.hi, oldHi)
+		}
+		oldHi = d.hi
+	}
+}
+
+// TestNoLongerSavingPriorExpansions tests the decoder state when codes other
+// than clear codes continue to be seen after decoder.hi and decoder.width
+// reach their maximum values (4095 and 12), i.e. after we no longer save prior
+// expansions. In particular, it tests seeing the highest possible code, 4095.
+func TestNoLongerSavingPriorExpansions(t *testing.T) {
+	// Iterations is used to calculate how many input bits are needed to get
+	// the decoder.hi and decoder.width values up to their maximum.
+	iterations := []struct {
+		width, n int
+	}{
+		// The final term is 257, not 256, as NewReader initializes d.hi to
+		// d.clear+1 and the clear code is 256.
+		{9, 512 - 257},
+		{10, 1024 - 512},
+		{11, 2048 - 1024},
+		{12, 4096 - 2048},
+	}
+	nCodes, nBits := 0, 0
+	for _, e := range iterations {
+		nCodes += e.n
+		nBits += e.n * e.width
+	}
+	if nCodes != 3839 {
+		t.Fatalf("nCodes: got %v, want %v", nCodes, 3839)
+	}
+	if nBits != 43255 {
+		t.Fatalf("nBits: got %v, want %v", nBits, 43255)
+	}
+
+	// Construct our input of 43255 zero bits (which gets d.hi and d.width up
+	// to 4095 and 12), followed by 0xfff (4095) as 12 bits, followed by 0x101
+	// (EOF) as 12 bits.
+	//
+	// 43255 = 5406*8 + 7, and codes are read in LSB order. The final bytes are
+	// therefore:
+	//
+	// xwwwwwww xxxxxxxx yyyyyxxx zyyyyyyy
+	// 10000000 11111111 00001111 00001000
+	//
+	// or split out:
+	//
+	// .0000000 ........ ........ ........   w = 0x000
+	// 1....... 11111111 .....111 ........   x = 0xfff
+	// ........ ........ 00001... .0001000   y = 0x101
+	//
+	// The 12 'w' bits (not all are shown) form the 3839'th code, with value
+	// 0x000. Just after decoder.read returns that code, d.hi == 4095 and
+	// d.last == 0.
+	//
+	// The 12 'x' bits form the 3840'th code, with value 0xfff or 4095. Just
+	// after decoder.read returns that code, d.hi == 4095 and d.last ==
+	// decoderInvalidCode.
+	//
+	// The 12 'y' bits form the 3841'st code, with value 0x101, the EOF code.
+	//
+	// The 'z' bit is unused.
+	in := make([]byte, 5406)
+	in = append(in, 0x80, 0xff, 0x0f, 0x08)
+
+	r := NewReader(bytes.NewReader(in), LSB, 8)
+	nDecoded, err := io.Copy(ioutil.Discard, r)
+	if err != nil {
+		t.Fatalf("Copy: %v", err)
+	}
+	// nDecoded should be 3841: 3839 literal codes and then 2 decoded bytes
+	// from 1 non-literal code. The EOF code contributes 0 decoded bytes.
+	if nDecoded != int64(nCodes+2) {
+		t.Fatalf("nDecoded: got %v, want %v", nDecoded, nCodes+2)
+	}
+}
+
 func BenchmarkDecoder(b *testing.B) {
 	buf, err := ioutil.ReadFile("../testdata/e.txt")
 	if err != nil {
diff --git a/libgo/go/container/heap/heap.go b/libgo/go/container/heap/heap.go
index 7110c51..b2c6427 100644
--- a/libgo/go/container/heap/heap.go
+++ b/libgo/go/container/heap/heap.go
@@ -72,8 +72,9 @@
 	n := h.Len() - 1
 	if n != i {
 		h.Swap(i, n)
-		down(h, i, n)
-		up(h, i)
+		if !down(h, i, n) {
+			up(h, i)
+		}
 	}
 	return h.Pop()
 }
@@ -107,7 +108,7 @@
 			break
 		}
 		j := j1 // left child
-		if j2 := j1 + 1; j2 < n && !h.Less(j1, j2) {
+		if j2 := j1 + 1; j2 < n && h.Less(j2, j1) {
 			j = j2 // = 2*i + 2  // right child
 		}
 		if !h.Less(j, i) {
diff --git a/libgo/go/context/context.go b/libgo/go/context/context.go
index 0aa7c24..892ff27 100644
--- a/libgo/go/context/context.go
+++ b/libgo/go/context/context.go
@@ -96,10 +96,11 @@
 	// a Done channel for cancelation.
 	Done() <-chan struct{}
 
-	// Err returns a non-nil error value after Done is closed. Err returns
-	// Canceled if the context was canceled or DeadlineExceeded if the
-	// context's deadline passed. No other values for Err are defined.
-	// After Done is closed, successive calls to Err return the same value.
+	// If Done is not yet closed, Err returns nil.
+	// If Done is closed, Err returns a non-nil error explaining why:
+	// Canceled if the context was canceled
+	// or DeadlineExceeded if the context's deadline passed.
+	// After Err returns a non-nil error, successive calls to Err return the same error.
 	Err() error
 
 	// Value returns the value associated with this context for key, or nil
@@ -234,10 +235,7 @@
 
 // newCancelCtx returns an initialized cancelCtx.
 func newCancelCtx(parent Context) cancelCtx {
-	return cancelCtx{
-		Context: parent,
-		done:    make(chan struct{}),
-	}
+	return cancelCtx{Context: parent}
 }
 
 // propagateCancel arranges for child to be canceled when parent is.
@@ -306,20 +304,32 @@
 	Done() <-chan struct{}
 }
 
+// closedchan is a reusable closed channel.
+var closedchan = make(chan struct{})
+
+func init() {
+	close(closedchan)
+}
+
 // A cancelCtx can be canceled. When canceled, it also cancels any children
 // that implement canceler.
 type cancelCtx struct {
 	Context
 
-	done chan struct{} // closed by the first cancel call.
-
-	mu       sync.Mutex
+	mu       sync.Mutex            // protects following fields
+	done     chan struct{}         // created lazily, closed by first cancel call
 	children map[canceler]struct{} // set to nil by the first cancel call
 	err      error                 // set to non-nil by the first cancel call
 }
 
 func (c *cancelCtx) Done() <-chan struct{} {
-	return c.done
+	c.mu.Lock()
+	if c.done == nil {
+		c.done = make(chan struct{})
+	}
+	d := c.done
+	c.mu.Unlock()
+	return d
 }
 
 func (c *cancelCtx) Err() error {
@@ -344,7 +354,11 @@
 		return // already canceled
 	}
 	c.err = err
-	close(c.done)
+	if c.done == nil {
+		c.done = closedchan
+	} else {
+		close(c.done)
+	}
 	for child := range c.children {
 		// NOTE: acquiring the child's lock while holding parent's lock.
 		child.cancel(false, err)
diff --git a/libgo/go/context/context_test.go b/libgo/go/context/context_test.go
index b5e599f..548476f 100644
--- a/libgo/go/context/context_test.go
+++ b/libgo/go/context/context_test.go
@@ -428,7 +428,7 @@
 		limit := test.limit
 		if runtime.Compiler == "gccgo" {
 			// gccgo does not yet do escape analysis.
-			// TOOD(iant): Remove this when gccgo does do escape analysis.
+			// TODO(iant): Remove this when gccgo does do escape analysis.
 			limit = test.gccgoLimit
 		}
 		numRuns := 100
diff --git a/libgo/go/crypto/aes/cipher_generic.go b/libgo/go/crypto/aes/cipher_generic.go
index 2c8d299..98169bf 100644
--- a/libgo/go/crypto/aes/cipher_generic.go
+++ b/libgo/go/crypto/aes/cipher_generic.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// -build !amd64,!s390x
+// -build !amd64,!s390x,!ppc64le
 
 package aes
 
diff --git a/libgo/go/crypto/aes/cipher_ppc64le.go b/libgo/go/crypto/aes/cipher_ppc64le.go
new file mode 100644
index 0000000..1d16fe0
--- /dev/null
+++ b/libgo/go/crypto/aes/cipher_ppc64le.go
@@ -0,0 +1,82 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package aes
+
+import (
+	"crypto/cipher"
+)
+
+// defined in asm_ppc64le.s
+
+//go:noescape
+
+func setEncryptKeyAsm(key *byte, keylen int, enc *uint32) int
+
+//go:noescape
+
+func setDecryptKeyAsm(key *byte, keylen int, dec *uint32) int
+
+//go:noescape
+
+func doEncryptKeyAsm(key *byte, keylen int, dec *uint32) int
+
+//go:noescape
+
+func encryptBlockAsm(dst, src *byte, enc *uint32)
+
+//go:noescape
+
+func decryptBlockAsm(dst, src *byte, dec *uint32)
+
+type aesCipherAsm struct {
+	aesCipher
+}
+
+func newCipher(key []byte) (cipher.Block, error) {
+	n := 64 // size is fixed for all and round value is stored inside it too
+	c := aesCipherAsm{aesCipher{make([]uint32, n), make([]uint32, n)}}
+	k := len(key)
+
+	ret := 0
+	ret += setEncryptKeyAsm(&key[0], k*8, &c.enc[0])
+	ret += setDecryptKeyAsm(&key[0], k*8, &c.dec[0])
+
+	if ret > 0 {
+		return nil, KeySizeError(k)
+	}
+
+	return &c, nil
+}
+
+func (c *aesCipherAsm) BlockSize() int { return BlockSize }
+
+func (c *aesCipherAsm) Encrypt(dst, src []byte) {
+	if len(src) < BlockSize {
+		panic("crypto/aes: input not full block")
+	}
+	if len(dst) < BlockSize {
+		panic("crypto/aes: output not full block")
+	}
+	encryptBlockAsm(&dst[0], &src[0], &c.enc[0])
+}
+
+func (c *aesCipherAsm) Decrypt(dst, src []byte) {
+	if len(src) < BlockSize {
+		panic("crypto/aes: input not full block")
+	}
+	if len(dst) < BlockSize {
+		panic("crypto/aes: output not full block")
+	}
+	decryptBlockAsm(&dst[0], &src[0], &c.dec[0])
+}
+
+// expandKey is used by BenchmarkExpand to ensure that the asm implementation
+// of key expansion is used for the benchmark when it is available.
+func expandKey(key []byte, enc, dec []uint32) {
+	setEncryptKeyAsm(&key[0], len(key)*8, &enc[0])
+	setDecryptKeyAsm(&key[0], len(key)*8, &dec[0])
+}
diff --git a/libgo/go/crypto/crypto.go b/libgo/go/crypto/crypto.go
index a80ebd3..b4d6cdc 100644
--- a/libgo/go/crypto/crypto.go
+++ b/libgo/go/crypto/crypto.go
@@ -21,40 +21,48 @@
 }
 
 const (
-	MD4        Hash = 1 + iota // import golang.org/x/crypto/md4
-	MD5                        // import crypto/md5
-	SHA1                       // import crypto/sha1
-	SHA224                     // import crypto/sha256
-	SHA256                     // import crypto/sha256
-	SHA384                     // import crypto/sha512
-	SHA512                     // import crypto/sha512
-	MD5SHA1                    // no implementation; MD5+SHA1 used for TLS RSA
-	RIPEMD160                  // import golang.org/x/crypto/ripemd160
-	SHA3_224                   // import golang.org/x/crypto/sha3
-	SHA3_256                   // import golang.org/x/crypto/sha3
-	SHA3_384                   // import golang.org/x/crypto/sha3
-	SHA3_512                   // import golang.org/x/crypto/sha3
-	SHA512_224                 // import crypto/sha512
-	SHA512_256                 // import crypto/sha512
+	MD4         Hash = 1 + iota // import golang.org/x/crypto/md4
+	MD5                         // import crypto/md5
+	SHA1                        // import crypto/sha1
+	SHA224                      // import crypto/sha256
+	SHA256                      // import crypto/sha256
+	SHA384                      // import crypto/sha512
+	SHA512                      // import crypto/sha512
+	MD5SHA1                     // no implementation; MD5+SHA1 used for TLS RSA
+	RIPEMD160                   // import golang.org/x/crypto/ripemd160
+	SHA3_224                    // import golang.org/x/crypto/sha3
+	SHA3_256                    // import golang.org/x/crypto/sha3
+	SHA3_384                    // import golang.org/x/crypto/sha3
+	SHA3_512                    // import golang.org/x/crypto/sha3
+	SHA512_224                  // import crypto/sha512
+	SHA512_256                  // import crypto/sha512
+	BLAKE2s_256                 // import golang.org/x/crypto/blake2s
+	BLAKE2b_256                 // import golang.org/x/crypto/blake2b
+	BLAKE2b_384                 // import golang.org/x/crypto/blake2b
+	BLAKE2b_512                 // import golang.org/x/crypto/blake2b
 	maxHash
 )
 
 var digestSizes = []uint8{
-	MD4:        16,
-	MD5:        16,
-	SHA1:       20,
-	SHA224:     28,
-	SHA256:     32,
-	SHA384:     48,
-	SHA512:     64,
-	SHA512_224: 28,
-	SHA512_256: 32,
-	SHA3_224:   28,
-	SHA3_256:   32,
-	SHA3_384:   48,
-	SHA3_512:   64,
-	MD5SHA1:    36,
-	RIPEMD160:  20,
+	MD4:         16,
+	MD5:         16,
+	SHA1:        20,
+	SHA224:      28,
+	SHA256:      32,
+	SHA384:      48,
+	SHA512:      64,
+	SHA512_224:  28,
+	SHA512_256:  32,
+	SHA3_224:    28,
+	SHA3_256:    32,
+	SHA3_384:    48,
+	SHA3_512:    64,
+	MD5SHA1:     36,
+	RIPEMD160:   20,
+	BLAKE2s_256: 32,
+	BLAKE2b_256: 32,
+	BLAKE2b_384: 48,
+	BLAKE2b_512: 64,
 }
 
 // Size returns the length, in bytes, of a digest resulting from the given hash
diff --git a/libgo/go/crypto/des/block.go b/libgo/go/crypto/des/block.go
index 99338d6..21e6d4e 100644
--- a/libgo/go/crypto/des/block.go
+++ b/libgo/go/crypto/des/block.go
@@ -4,25 +4,29 @@
 
 package des
 
-import (
-	"encoding/binary"
-)
+import "encoding/binary"
 
 func cryptBlock(subkeys []uint64, dst, src []byte, decrypt bool) {
 	b := binary.BigEndian.Uint64(src)
 	b = permuteInitialBlock(b)
 	left, right := uint32(b>>32), uint32(b)
 
-	var subkey uint64
-	for i := 0; i < 16; i++ {
-		if decrypt {
-			subkey = subkeys[15-i]
-		} else {
-			subkey = subkeys[i]
-		}
+	left = (left << 1) | (left >> 31)
+	right = (right << 1) | (right >> 31)
 
-		left, right = right, left^feistel(right, subkey)
+	if decrypt {
+		for i := 0; i < 8; i++ {
+			left, right = feistel(left, right, subkeys[15-2*i], subkeys[15-(2*i+1)])
+		}
+	} else {
+		for i := 0; i < 8; i++ {
+			left, right = feistel(left, right, subkeys[2*i], subkeys[2*i+1])
+		}
 	}
+
+	left = (left << 31) | (left >> 1)
+	right = (right << 31) | (right >> 1)
+
 	// switch left & right and perform final permutation
 	preOutput := (uint64(right) << 32) | uint64(left)
 	binary.BigEndian.PutUint64(dst, permuteFinalBlock(preOutput))
@@ -39,19 +43,34 @@
 }
 
 // DES Feistel function
-func feistel(right uint32, key uint64) (result uint32) {
-	sBoxLocations := key ^ expandBlock(right)
-	var sBoxResult uint32
-	for i := uint8(0); i < 8; i++ {
-		sBoxLocation := uint8(sBoxLocations>>42) & 0x3f
-		sBoxLocations <<= 6
-		// row determined by 1st and 6th bit
-		// column is middle four bits
-		row := (sBoxLocation & 0x1) | ((sBoxLocation & 0x20) >> 4)
-		column := (sBoxLocation >> 1) & 0xf
-		sBoxResult ^= feistelBox[i][16*row+column]
-	}
-	return sBoxResult
+func feistel(l, r uint32, k0, k1 uint64) (lout, rout uint32) {
+	var t uint32
+
+	t = r ^ uint32(k0>>32)
+	l ^= feistelBox[7][t&0x3f] ^
+		feistelBox[5][(t>>8)&0x3f] ^
+		feistelBox[3][(t>>16)&0x3f] ^
+		feistelBox[1][(t>>24)&0x3f]
+
+	t = ((r << 28) | (r >> 4)) ^ uint32(k0)
+	l ^= feistelBox[6][(t)&0x3f] ^
+		feistelBox[4][(t>>8)&0x3f] ^
+		feistelBox[2][(t>>16)&0x3f] ^
+		feistelBox[0][(t>>24)&0x3f]
+
+	t = l ^ uint32(k1>>32)
+	r ^= feistelBox[7][t&0x3f] ^
+		feistelBox[5][(t>>8)&0x3f] ^
+		feistelBox[3][(t>>16)&0x3f] ^
+		feistelBox[1][(t>>24)&0x3f]
+
+	t = ((l << 28) | (l >> 4)) ^ uint32(k1)
+	r ^= feistelBox[6][(t)&0x3f] ^
+		feistelBox[4][(t>>8)&0x3f] ^
+		feistelBox[2][(t>>16)&0x3f] ^
+		feistelBox[0][(t>>24)&0x3f]
+
+	return l, r
 }
 
 // feistelBox[s][16*i+j] contains the output of permutationFunction
@@ -73,27 +92,22 @@
 			for j := 0; j < 16; j++ {
 				f := uint64(sBoxes[s][i][j]) << (4 * (7 - uint(s)))
 				f = permuteBlock(f, permutationFunction[:])
-				feistelBox[s][16*i+j] = uint32(f)
+
+				// Row is determined by the 1st and 6th bit.
+				// Column is the middle four bits.
+				row := uint8(((i & 2) << 4) | i&1)
+				col := uint8(j << 1)
+				t := row | col
+
+				// The rotation was performed in the feistel rounds, being factored out and now mixed into the feistelBox.
+				f = (f << 1) | (f >> 31)
+
+				feistelBox[s][t] = uint32(f)
 			}
 		}
 	}
 }
 
-// expandBlock expands an input block of 32 bits,
-// producing an output block of 48 bits.
-func expandBlock(src uint32) (block uint64) {
-	// rotate the 5 highest bits to the right.
-	src = (src << 5) | (src >> 27)
-	for i := 0; i < 8; i++ {
-		block <<= 6
-		// take the 6 bits on the right
-		block |= uint64(src) & (1<<6 - 1)
-		// advance by 4 bits.
-		src = (src << 4) | (src >> 28)
-	}
-	return
-}
-
 // permuteInitialBlock is equivalent to the permutation defined
 // by initialPermutation.
 func permuteInitialBlock(block uint64) uint64 {
@@ -218,6 +232,24 @@
 		// combine halves to form 56-bit input to PC2
 		pc2Input := uint64(leftRotations[i])<<28 | uint64(rightRotations[i])
 		// apply PC2 permutation to 7 byte input
-		c.subkeys[i] = permuteBlock(pc2Input, permutedChoice2[:])
+		c.subkeys[i] = unpack(permuteBlock(pc2Input, permutedChoice2[:]))
 	}
 }
+
+// Expand 48-bit input to 64-bit, with each 6-bit block padded by extra two bits at the top.
+// By doing so, we can have the input blocks (four bits each), and the key blocks (six bits each) well-aligned without
+// extra shifts/rotations for alignments.
+func unpack(x uint64) uint64 {
+	var result uint64
+
+	result = ((x>>(6*1))&0xff)<<(8*0) |
+		((x>>(6*3))&0xff)<<(8*1) |
+		((x>>(6*5))&0xff)<<(8*2) |
+		((x>>(6*7))&0xff)<<(8*3) |
+		((x>>(6*0))&0xff)<<(8*4) |
+		((x>>(6*2))&0xff)<<(8*5) |
+		((x>>(6*4))&0xff)<<(8*6) |
+		((x>>(6*6))&0xff)<<(8*7)
+
+	return result
+}
diff --git a/libgo/go/crypto/des/cipher.go b/libgo/go/crypto/des/cipher.go
index 2f929ca..46af5b0 100644
--- a/libgo/go/crypto/des/cipher.go
+++ b/libgo/go/crypto/des/cipher.go
@@ -6,6 +6,7 @@
 
 import (
 	"crypto/cipher"
+	"encoding/binary"
 	"strconv"
 )
 
@@ -61,13 +62,51 @@
 func (c *tripleDESCipher) BlockSize() int { return BlockSize }
 
 func (c *tripleDESCipher) Encrypt(dst, src []byte) {
-	c.cipher1.Encrypt(dst, src)
-	c.cipher2.Decrypt(dst, dst)
-	c.cipher3.Encrypt(dst, dst)
+	b := binary.BigEndian.Uint64(src)
+	b = permuteInitialBlock(b)
+	left, right := uint32(b>>32), uint32(b)
+
+	left = (left << 1) | (left >> 31)
+	right = (right << 1) | (right >> 31)
+
+	for i := 0; i < 8; i++ {
+		left, right = feistel(left, right, c.cipher1.subkeys[2*i], c.cipher1.subkeys[2*i+1])
+	}
+	for i := 0; i < 8; i++ {
+		right, left = feistel(right, left, c.cipher2.subkeys[15-2*i], c.cipher2.subkeys[15-(2*i+1)])
+	}
+	for i := 0; i < 8; i++ {
+		left, right = feistel(left, right, c.cipher3.subkeys[2*i], c.cipher3.subkeys[2*i+1])
+	}
+
+	left = (left << 31) | (left >> 1)
+	right = (right << 31) | (right >> 1)
+
+	preOutput := (uint64(right) << 32) | uint64(left)
+	binary.BigEndian.PutUint64(dst, permuteFinalBlock(preOutput))
 }
 
 func (c *tripleDESCipher) Decrypt(dst, src []byte) {
-	c.cipher3.Decrypt(dst, src)
-	c.cipher2.Encrypt(dst, dst)
-	c.cipher1.Decrypt(dst, dst)
+	b := binary.BigEndian.Uint64(src)
+	b = permuteInitialBlock(b)
+	left, right := uint32(b>>32), uint32(b)
+
+	left = (left << 1) | (left >> 31)
+	right = (right << 1) | (right >> 31)
+
+	for i := 0; i < 8; i++ {
+		left, right = feistel(left, right, c.cipher3.subkeys[15-2*i], c.cipher3.subkeys[15-(2*i+1)])
+	}
+	for i := 0; i < 8; i++ {
+		right, left = feistel(right, left, c.cipher2.subkeys[2*i], c.cipher2.subkeys[2*i+1])
+	}
+	for i := 0; i < 8; i++ {
+		left, right = feistel(left, right, c.cipher1.subkeys[15-2*i], c.cipher1.subkeys[15-(2*i+1)])
+	}
+
+	left = (left << 31) | (left >> 1)
+	right = (right << 31) | (right >> 1)
+
+	preOutput := (uint64(right) << 32) | uint64(left)
+	binary.BigEndian.PutUint64(dst, permuteFinalBlock(preOutput))
 }
diff --git a/libgo/go/crypto/des/const.go b/libgo/go/crypto/des/const.go
index 2bd485e..a20879d 100644
--- a/libgo/go/crypto/des/const.go
+++ b/libgo/go/crypto/des/const.go
@@ -5,6 +5,9 @@
 // Package des implements the Data Encryption Standard (DES) and the
 // Triple Data Encryption Algorithm (TDEA) as defined
 // in U.S. Federal Information Processing Standards Publication 46-3.
+//
+// DES is cryptographically broken and should not be used for secure
+// applications.
 package des
 
 // Used to perform an initial permutation of a 64-bit input block.
diff --git a/libgo/go/crypto/des/des_test.go b/libgo/go/crypto/des/des_test.go
index 2bd525a..690a49f 100644
--- a/libgo/go/crypto/des/des_test.go
+++ b/libgo/go/crypto/des/des_test.go
@@ -1526,17 +1526,6 @@
 	}
 }
 
-func TestExpandBlock(t *testing.T) {
-	for i := uint(0); i < 32; i++ {
-		bit := uint32(1) << i
-		got := expandBlock(bit)
-		want := permuteBlock(uint64(bit), expansionFunction[:])
-		if got != want {
-			t.Errorf("expand(%x) = %x, want %x", bit, got, want)
-		}
-	}
-}
-
 func BenchmarkEncrypt(b *testing.B) {
 	tt := encryptDESTests[0]
 	c, err := NewCipher(tt.key)
@@ -1564,3 +1553,31 @@
 		c.Decrypt(out, tt.out)
 	}
 }
+
+func BenchmarkTDESEncrypt(b *testing.B) {
+	tt := encryptTripleDESTests[0]
+	c, err := NewTripleDESCipher(tt.key)
+	if err != nil {
+		b.Fatal("NewCipher:", err)
+	}
+	out := make([]byte, len(tt.in))
+	b.SetBytes(int64(len(out)))
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		c.Encrypt(out, tt.in)
+	}
+}
+
+func BenchmarkTDESDecrypt(b *testing.B) {
+	tt := encryptTripleDESTests[0]
+	c, err := NewTripleDESCipher(tt.key)
+	if err != nil {
+		b.Fatal("NewCipher:", err)
+	}
+	out := make([]byte, len(tt.out))
+	b.SetBytes(int64(len(out)))
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		c.Decrypt(out, tt.out)
+	}
+}
diff --git a/libgo/go/crypto/dsa/dsa_test.go b/libgo/go/crypto/dsa/dsa_test.go
index 8600059..7fc246b 100644
--- a/libgo/go/crypto/dsa/dsa_test.go
+++ b/libgo/go/crypto/dsa/dsa_test.go
@@ -82,12 +82,17 @@
 }
 
 func TestSignAndVerify(t *testing.T) {
-	var priv PrivateKey
-	priv.P, _ = new(big.Int).SetString("A9B5B793FB4785793D246BAE77E8FF63CA52F442DA763C440259919FE1BC1D6065A9350637A04F75A2F039401D49F08E066C4D275A5A65DA5684BC563C14289D7AB8A67163BFBF79D85972619AD2CFF55AB0EE77A9002B0EF96293BDD0F42685EBB2C66C327079F6C98000FBCB79AACDE1BC6F9D5C7B1A97E3D9D54ED7951FEF", 16)
-	priv.Q, _ = new(big.Int).SetString("E1D3391245933D68A0714ED34BBCB7A1F422B9C1", 16)
-	priv.G, _ = new(big.Int).SetString("634364FC25248933D01D1993ECABD0657CC0CB2CEED7ED2E3E8AECDFCDC4A25C3B15E9E3B163ACA2984B5539181F3EFF1A5E8903D71D5B95DA4F27202B77D2C44B430BB53741A8D59A8F86887525C9F2A6A5980A195EAA7F2FF910064301DEF89D3AA213E1FAC7768D89365318E370AF54A112EFBA9246D9158386BA1B4EEFDA", 16)
-	priv.Y, _ = new(big.Int).SetString("32969E5780CFE1C849A1C276D7AEB4F38A23B591739AA2FE197349AEEBD31366AEE5EB7E6C6DDB7C57D02432B30DB5AA66D9884299FAA72568944E4EEDC92EA3FBC6F39F53412FBCC563208F7C15B737AC8910DBC2D9C9B8C001E72FDC40EB694AB1F06A5A2DBD18D9E36C66F31F566742F11EC0A52E9F7B89355C02FB5D32D2", 16)
-	priv.X, _ = new(big.Int).SetString("5078D4D29795CBE76D3AACFE48C9AF0BCDBEE91A", 16)
+	priv := PrivateKey{
+		PublicKey: PublicKey{
+			Parameters: Parameters{
+				P: fromHex("A9B5B793FB4785793D246BAE77E8FF63CA52F442DA763C440259919FE1BC1D6065A9350637A04F75A2F039401D49F08E066C4D275A5A65DA5684BC563C14289D7AB8A67163BFBF79D85972619AD2CFF55AB0EE77A9002B0EF96293BDD0F42685EBB2C66C327079F6C98000FBCB79AACDE1BC6F9D5C7B1A97E3D9D54ED7951FEF"),
+				Q: fromHex("E1D3391245933D68A0714ED34BBCB7A1F422B9C1"),
+				G: fromHex("634364FC25248933D01D1993ECABD0657CC0CB2CEED7ED2E3E8AECDFCDC4A25C3B15E9E3B163ACA2984B5539181F3EFF1A5E8903D71D5B95DA4F27202B77D2C44B430BB53741A8D59A8F86887525C9F2A6A5980A195EAA7F2FF910064301DEF89D3AA213E1FAC7768D89365318E370AF54A112EFBA9246D9158386BA1B4EEFDA"),
+			},
+			Y: fromHex("32969E5780CFE1C849A1C276D7AEB4F38A23B591739AA2FE197349AEEBD31366AEE5EB7E6C6DDB7C57D02432B30DB5AA66D9884299FAA72568944E4EEDC92EA3FBC6F39F53412FBCC563208F7C15B737AC8910DBC2D9C9B8C001E72FDC40EB694AB1F06A5A2DBD18D9E36C66F31F566742F11EC0A52E9F7B89355C02FB5D32D2"),
+		},
+		X: fromHex("5078D4D29795CBE76D3AACFE48C9AF0BCDBEE91A"),
+	}
 
 	testSignAndVerify(t, 0, &priv)
 }
diff --git a/libgo/go/crypto/md5/md5.go b/libgo/go/crypto/md5/md5.go
index ce58d5e..b682f00 100644
--- a/libgo/go/crypto/md5/md5.go
+++ b/libgo/go/crypto/md5/md5.go
@@ -5,6 +5,9 @@
 //go:generate go run gen.go -full -output md5block.go
 
 // Package md5 implements the MD5 hash algorithm as defined in RFC 1321.
+//
+// MD5 is cryptographically broken and should not be used for secure
+// applications.
 package md5
 
 import (
diff --git a/libgo/go/crypto/rand/rand_linux.go b/libgo/go/crypto/rand/rand_linux.go
index 472daa7..8a4c757 100644
--- a/libgo/go/crypto/rand/rand_linux.go
+++ b/libgo/go/crypto/rand/rand_linux.go
@@ -6,34 +6,20 @@
 
 import (
 	"internal/syscall/unix"
-	"sync"
 )
 
 func init() {
 	altGetRandom = getRandomLinux
 }
 
-var (
-	once       sync.Once
-	useSyscall bool
-)
-
-func pickStrategy() {
-	// Test whether we should use the system call or /dev/urandom.
-	// We'll fall back to urandom if:
-	// - the kernel is too old (before 3.17)
-	// - the machine has no entropy available (early boot + no hardware
-	//   entropy source?) and we want to avoid blocking later.
-	var buf [1]byte
-	n, err := unix.GetRandom(buf[:], unix.GRND_NONBLOCK)
-	useSyscall = n == 1 && err == nil
-}
-
+// If the kernel is too old (before 3.17) to support the getrandom syscall(),
+// unix.GetRandom will immediately return ENOSYS and we will then fall back to
+// reading from /dev/urandom in rand_unix.go. unix.GetRandom caches the ENOSYS
+// result so we only suffer the syscall overhead once in this case.
+// If the kernel supports the getrandom() syscall, unix.GetRandom will block
+// until the kernel has sufficient randomness (as we don't use GRND_NONBLOCK).
+// In this case, unix.GetRandom will not return an error.
 func getRandomLinux(p []byte) (ok bool) {
-	once.Do(pickStrategy)
-	if !useSyscall {
-		return false
-	}
 	n, err := unix.GetRandom(p, 0)
 	return n == len(p) && err == nil
 }
diff --git a/libgo/go/crypto/rand/util.go b/libgo/go/crypto/rand/util.go
index 592c57e..4dd1711 100644
--- a/libgo/go/crypto/rand/util.go
+++ b/libgo/go/crypto/rand/util.go
@@ -107,16 +107,23 @@
 	if max.Sign() <= 0 {
 		panic("crypto/rand: argument to Int is <= 0")
 	}
-	k := (max.BitLen() + 7) / 8
-
-	// b is the number of bits in the most significant byte of max.
-	b := uint(max.BitLen() % 8)
+	n = new(big.Int)
+	n.Sub(max, n.SetUint64(1))
+	// bitLen is the maximum bit length needed to encode a value < max.
+	bitLen := n.BitLen()
+	if bitLen == 0 {
+		// the only valid result is 0
+		return
+	}
+	// k is the maximum byte length needed to encode a value < max.
+	k := (bitLen + 7) / 8
+	// b is the number of bits in the most significant byte of max-1.
+	b := uint(bitLen % 8)
 	if b == 0 {
 		b = 8
 	}
 
 	bytes := make([]byte, k)
-	n = new(big.Int)
 
 	for {
 		_, err = io.ReadFull(rand, bytes)
diff --git a/libgo/go/crypto/rand/util_test.go b/libgo/go/crypto/rand/util_test.go
index 48a2c3f..685624e 100644
--- a/libgo/go/crypto/rand/util_test.go
+++ b/libgo/go/crypto/rand/util_test.go
@@ -5,7 +5,10 @@
 package rand_test
 
 import (
+	"bytes"
 	"crypto/rand"
+	"fmt"
+	"io"
 	"math/big"
 	mathrand "math/rand"
 	"testing"
@@ -45,6 +48,56 @@
 	}
 }
 
+type countingReader struct {
+	r io.Reader
+	n int
+}
+
+func (r *countingReader) Read(p []byte) (n int, err error) {
+	n, err = r.r.Read(p)
+	r.n += n
+	return n, err
+}
+
+// Test that Int reads only the necessary number of bytes from the reader for
+// max at each bit length
+func TestIntReads(t *testing.T) {
+	for i := 0; i < 32; i++ {
+		max := int64(1 << uint64(i))
+		t.Run(fmt.Sprintf("max=%d", max), func(t *testing.T) {
+			reader := &countingReader{r: rand.Reader}
+
+			_, err := rand.Int(reader, big.NewInt(max))
+			if err != nil {
+				t.Fatalf("Can't generate random value: %d, %v", max, err)
+			}
+			expected := (i + 7) / 8
+			if reader.n != expected {
+				t.Errorf("Int(reader, %d) should read %d bytes, but it read: %d", max, expected, reader.n)
+			}
+		})
+	}
+}
+
+// Test that Int does not mask out valid return values
+func TestIntMask(t *testing.T) {
+	for max := 1; max <= 256; max++ {
+		t.Run(fmt.Sprintf("max=%d", max), func(t *testing.T) {
+			for i := 0; i < max; i++ {
+				var b bytes.Buffer
+				b.WriteByte(byte(i))
+				n, err := rand.Int(&b, big.NewInt(int64(max)))
+				if err != nil {
+					t.Fatalf("Can't generate random value: %d, %v", max, err)
+				}
+				if n.Int64() != int64(i) {
+					t.Errorf("Int(reader, %d) should have returned value of %d, but it returned: %v", max, i, n)
+				}
+			}
+		})
+	}
+}
+
 func testIntPanics(t *testing.T, b *big.Int) {
 	defer func() {
 		if err := recover(); err == nil {
diff --git a/libgo/go/crypto/rc4/rc4.go b/libgo/go/crypto/rc4/rc4.go
index bd04aee..772af0e 100644
--- a/libgo/go/crypto/rc4/rc4.go
+++ b/libgo/go/crypto/rc4/rc4.go
@@ -4,11 +4,11 @@
 
 // Package rc4 implements RC4 encryption, as defined in Bruce Schneier's
 // Applied Cryptography.
+//
+// RC4 is cryptographically broken and should not be used for secure
+// applications.
 package rc4
 
-// BUG(agl): RC4 is in common use but has design weaknesses that make
-// it a poor choice for new protocols.
-
 import "strconv"
 
 // A Cipher is an instance of RC4 using a particular key.
diff --git a/libgo/go/crypto/sha1/sha1.go b/libgo/go/crypto/sha1/sha1.go
index fbb2f94..6b17214 100644
--- a/libgo/go/crypto/sha1/sha1.go
+++ b/libgo/go/crypto/sha1/sha1.go
@@ -2,7 +2,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package sha1 implements the SHA1 hash algorithm as defined in RFC 3174.
+// Package sha1 implements the SHA-1 hash algorithm as defined in RFC 3174.
+//
+// SHA-1 is cryptographically broken and should not be used for secure
+// applications.
 package sha1
 
 import (
@@ -14,10 +17,10 @@
 	crypto.RegisterHash(crypto.SHA1, New)
 }
 
-// The size of a SHA1 checksum in bytes.
+// The size of a SHA-1 checksum in bytes.
 const Size = 20
 
-// The blocksize of SHA1 in bytes.
+// The blocksize of SHA-1 in bytes.
 const BlockSize = 64
 
 const (
@@ -189,7 +192,7 @@
 	return digest
 }
 
-// Sum returns the SHA1 checksum of the data.
+// Sum returns the SHA-1 checksum of the data.
 func Sum(data []byte) [Size]byte {
 	var d digest
 	d.Reset()
diff --git a/libgo/go/crypto/sha1/sha1_test.go b/libgo/go/crypto/sha1/sha1_test.go
index 3e59a5d..faa9916 100644
--- a/libgo/go/crypto/sha1/sha1_test.go
+++ b/libgo/go/crypto/sha1/sha1_test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// SHA1 hash algorithm. See RFC 3174.
+// SHA-1 hash algorithm. See RFC 3174.
 
 package sha1
 
diff --git a/libgo/go/crypto/sha1/sha1block.go b/libgo/go/crypto/sha1/sha1block.go
index fde3c98..1d37544 100644
--- a/libgo/go/crypto/sha1/sha1block.go
+++ b/libgo/go/crypto/sha1/sha1block.go
@@ -11,7 +11,7 @@
 	_K3 = 0xCA62C1D6
 )
 
-// blockGeneric is a portable, pure Go version of the SHA1 block step.
+// blockGeneric is a portable, pure Go version of the SHA-1 block step.
 // It's used by sha1block_generic.go and tests.
 func blockGeneric(dig *digest, p []byte) {
 	var w [16]uint32
diff --git a/libgo/go/crypto/sha1/sha1block_amd64.go b/libgo/go/crypto/sha1/sha1block_amd64.go
index 8ef8b1f..2d7a314 100644
--- a/libgo/go/crypto/sha1/sha1block_amd64.go
+++ b/libgo/go/crypto/sha1/sha1block_amd64.go
@@ -6,18 +6,18 @@
 
 package sha1
 
-//go:noescape
+import "internal/cpu"
 
+//go:noescape
 func blockAVX2(dig *digest, p []byte)
 
 //go:noescape
 func blockAMD64(dig *digest, p []byte)
-func checkAVX2() bool
 
-var hasAVX2 = checkAVX2()
+var useAVX2 = cpu.X86.HasAVX2 && cpu.X86.HasBMI1 && cpu.X86.HasBMI2
 
 func block(dig *digest, p []byte) {
-	if hasAVX2 && len(p) >= 256 {
+	if useAVX2 && len(p) >= 256 {
 		// blockAVX2 calculates sha1 for 2 block per iteration
 		// it also interleaves precalculation for next block.
 		// So it may read up-to 192 bytes past end of p
diff --git a/libgo/go/crypto/sha1/sha1block_s390x.go b/libgo/go/crypto/sha1/sha1block_s390x.go
index 9edcbb0..55a2359 100644
--- a/libgo/go/crypto/sha1/sha1block_s390x.go
+++ b/libgo/go/crypto/sha1/sha1block_s390x.go
@@ -7,7 +7,7 @@
 package sha1
 
 // featureCheck reports whether the CPU supports the
-// SHA1 compute intermediate message digest (KIMD)
+// SHA-1 compute intermediate message digest (KIMD)
 // function code.
 func featureCheck() bool
 
diff --git a/libgo/go/crypto/sha256/sha256block_amd64.go b/libgo/go/crypto/sha256/sha256block_amd64.go
new file mode 100644
index 0000000..b311a12
--- /dev/null
+++ b/libgo/go/crypto/sha256/sha256block_amd64.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package sha256
+
+import "internal/cpu"
+
+var useAVX2 = cpu.X86.HasAVX2 && cpu.X86.HasBMI2
diff --git a/libgo/go/crypto/sha512/sha512block_amd64.go b/libgo/go/crypto/sha512/sha512block_amd64.go
new file mode 100644
index 0000000..0ce599b
--- /dev/null
+++ b/libgo/go/crypto/sha512/sha512block_amd64.go
@@ -0,0 +1,26 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+// +build amd64
+
+package sha512
+
+import "internal/cpu"
+
+//go:noescape
+func blockAVX2(dig *digest, p []byte)
+
+//go:noescape
+func blockAMD64(dig *digest, p []byte)
+
+var useAVX2 = cpu.X86.HasAVX2 && cpu.X86.HasBMI1 && cpu.X86.HasBMI2
+
+func block(dig *digest, p []byte) {
+	if useAVX2 {
+		blockAVX2(dig, p)
+	} else {
+		blockAMD64(dig, p)
+	}
+}
diff --git a/libgo/go/crypto/sha512/sha512block_decl.go b/libgo/go/crypto/sha512/sha512block_decl.go
index 3859a40..3d098c5 100644
--- a/libgo/go/crypto/sha512/sha512block_decl.go
+++ b/libgo/go/crypto/sha512/sha512block_decl.go
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build ignore
-// +build amd64 s390x ppc64le
+// +build s390x ppc64le
 
 package sha512
 
diff --git a/libgo/go/crypto/tls/common.go b/libgo/go/crypto/tls/common.go
index de833a9..5860838 100644
--- a/libgo/go/crypto/tls/common.go
+++ b/libgo/go/crypto/tls/common.go
@@ -163,8 +163,8 @@
 	HandshakeComplete           bool                  // TLS handshake is complete
 	DidResume                   bool                  // connection resumes a previous TLS connection
 	CipherSuite                 uint16                // cipher suite in use (TLS_RSA_WITH_RC4_128_SHA, ...)
-	NegotiatedProtocol          string                // negotiated next protocol (from Config.NextProtos)
-	NegotiatedProtocolIsMutual  bool                  // negotiated protocol was advertised by server
+	NegotiatedProtocol          string                // negotiated next protocol (not guaranteed to be from Config.NextProtos)
+	NegotiatedProtocolIsMutual  bool                  // negotiated protocol was advertised by server (client side only)
 	ServerName                  string                // server name requested by client, if any (server side only)
 	PeerCertificates            []*x509.Certificate   // certificate chain presented by remote peer
 	VerifiedChains              [][]*x509.Certificate // verified chains built from PeerCertificates
@@ -174,9 +174,9 @@
 	// TLSUnique contains the "tls-unique" channel binding value (see RFC
 	// 5929, section 3). For resumed sessions this value will be nil
 	// because resumption does not include enough context (see
-	// https://secure-resumption.com/#channelbindings). This will change in
-	// future versions of Go once the TLS master-secret fix has been
-	// standardized and implemented.
+	// https://mitls.org/pages/attacks/3SHAKE#channelbindings). This will
+	// change in future versions of Go once the TLS master-secret fix has
+	// been standardized and implemented.
 	TLSUnique []byte
 }
 
@@ -206,7 +206,8 @@
 // ClientSessionCache is a cache of ClientSessionState objects that can be used
 // by a client to resume a TLS session with a given server. ClientSessionCache
 // implementations should expect to be called concurrently from different
-// goroutines.
+// goroutines. Only ticket-based resumption is supported, not SessionID-based
+// resumption.
 type ClientSessionCache interface {
 	// Get searches for a ClientSessionState associated with the given key.
 	// On return, ok is true if one was found.
@@ -508,17 +509,13 @@
 
 	serverInitOnce sync.Once // guards calling (*Config).serverInit
 
-	// mutex protects sessionTicketKeys and originalConfig.
+	// mutex protects sessionTicketKeys.
 	mutex sync.RWMutex
 	// sessionTicketKeys contains zero or more ticket keys. If the length
 	// is zero, SessionTicketsDisabled must be true. The first key is used
 	// for new tickets and any subsequent keys can be used to decrypt old
 	// tickets.
 	sessionTicketKeys []ticketKey
-	// originalConfig is set to the Config that was passed to Server if
-	// this Config is returned by a GetConfigForClient callback. It's used
-	// by serverInit in order to copy session ticket keys if needed.
-	originalConfig *Config
 }
 
 // ticketKeyNameLen is the number of bytes of identifier that is prepended to
@@ -550,7 +547,7 @@
 func (c *Config) Clone() *Config {
 	// Running serverInit ensures that it's safe to read
 	// SessionTicketsDisabled.
-	c.serverInitOnce.Do(c.serverInit)
+	c.serverInitOnce.Do(func() { c.serverInit(nil) })
 
 	var sessionTicketKeys []ticketKey
 	c.mutex.RLock()
@@ -584,20 +581,17 @@
 		Renegotiation:               c.Renegotiation,
 		KeyLogWriter:                c.KeyLogWriter,
 		sessionTicketKeys:           sessionTicketKeys,
-		// originalConfig is deliberately not duplicated.
 	}
 }
 
-func (c *Config) serverInit() {
+// serverInit is run under c.serverInitOnce to do initialization of c. If c was
+// returned by a GetConfigForClient callback then the argument should be the
+// Config that was passed to Server, otherwise it should be nil.
+func (c *Config) serverInit(originalConfig *Config) {
 	if c.SessionTicketsDisabled || len(c.ticketKeys()) != 0 {
 		return
 	}
 
-	var originalConfig *Config
-	c.mutex.Lock()
-	originalConfig, c.originalConfig = c.originalConfig, nil
-	c.mutex.Unlock()
-
 	alreadySet := false
 	for _, b := range c.SessionTicketKey {
 		if b != 0 {
@@ -947,9 +941,7 @@
 	}
 
 	varDefaultCipherSuites = make([]uint16, 0, len(cipherSuites))
-	for _, topCipher := range topCipherSuites {
-		varDefaultCipherSuites = append(varDefaultCipherSuites, topCipher)
-	}
+	varDefaultCipherSuites = append(varDefaultCipherSuites, topCipherSuites...)
 
 NextCipherSuite:
 	for _, suite := range cipherSuites {
diff --git a/libgo/go/crypto/tls/conn.go b/libgo/go/crypto/tls/conn.go
index 03895a7..e6d85aa 100644
--- a/libgo/go/crypto/tls/conn.go
+++ b/libgo/go/crypto/tls/conn.go
@@ -1206,10 +1206,10 @@
 	var alertErr error
 
 	c.handshakeMutex.Lock()
-	defer c.handshakeMutex.Unlock()
 	if c.handshakeComplete {
 		alertErr = c.closeNotify()
 	}
+	c.handshakeMutex.Unlock()
 
 	if err := c.conn.Close(); err != nil {
 		return err
diff --git a/libgo/go/crypto/tls/conn_test.go b/libgo/go/crypto/tls/conn_test.go
index 5e5c7a2..e27c541 100644
--- a/libgo/go/crypto/tls/conn_test.go
+++ b/libgo/go/crypto/tls/conn_test.go
@@ -138,7 +138,7 @@
 
 		tlsConn := Client(clientConn, config)
 		if err := tlsConn.Handshake(); err != nil {
-			t.Errorf("Error from client handshake: %s", err)
+			t.Errorf("Error from client handshake: %v", err)
 			return
 		}
 
@@ -147,12 +147,12 @@
 		var recordSizes []int
 
 		for {
-			n, err := clientConn.Read(recordHeader[:])
+			n, err := io.ReadFull(clientConn, recordHeader[:])
 			if err == io.EOF {
 				break
 			}
 			if err != nil || n != len(recordHeader) {
-				t.Errorf("Error from client read: %s", err)
+				t.Errorf("io.ReadFull = %d, %v", n, err)
 				return
 			}
 
@@ -161,9 +161,9 @@
 				record = make([]byte, length)
 			}
 
-			n, err = clientConn.Read(record[:length])
+			n, err = io.ReadFull(clientConn, record[:length])
 			if err != nil || n != length {
-				t.Errorf("Error from client read: %s", err)
+				t.Errorf("io.ReadFull = %d, %v", n, err)
 				return
 			}
 
@@ -241,3 +241,34 @@
 	config.CipherSuites = []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256}
 	runDynamicRecordSizingTest(t, config)
 }
+
+// hairpinConn is a net.Conn that makes a “hairpin” call when closed, back into
+// the tls.Conn which is calling it.
+type hairpinConn struct {
+	net.Conn
+	tlsConn *Conn
+}
+
+func (conn *hairpinConn) Close() error {
+	conn.tlsConn.ConnectionState()
+	return nil
+}
+
+func TestHairpinInClose(t *testing.T) {
+	// This tests that the underlying net.Conn can call back into the
+	// tls.Conn when being closed without deadlocking.
+	client, server := net.Pipe()
+	defer server.Close()
+	defer client.Close()
+
+	conn := &hairpinConn{client, nil}
+	tlsConn := Server(conn, &Config{
+		GetCertificate: func(*ClientHelloInfo) (*Certificate, error) {
+			panic("unreachable")
+		},
+	})
+	conn.tlsConn = tlsConn
+
+	// This call should not deadlock.
+	tlsConn.Close()
+}
diff --git a/libgo/go/crypto/tls/generate_cert.go b/libgo/go/crypto/tls/generate_cert.go
index 83f9916..8ee2b59 100644
--- a/libgo/go/crypto/tls/generate_cert.go
+++ b/libgo/go/crypto/tls/generate_cert.go
@@ -33,7 +33,7 @@
 	validFor   = flag.Duration("duration", 365*24*time.Hour, "Duration that certificate is valid for")
 	isCA       = flag.Bool("ca", false, "whether this cert should be its own Certificate Authority")
 	rsaBits    = flag.Int("rsa-bits", 2048, "Size of RSA key to generate. Ignored if --ecdsa-curve is set")
-	ecdsaCurve = flag.String("ecdsa-curve", "", "ECDSA curve to use to generate a key. Valid values are P224, P256, P384, P521")
+	ecdsaCurve = flag.String("ecdsa-curve", "", "ECDSA curve to use to generate a key. Valid values are P224, P256 (recommended), P384, P521")
 )
 
 func publicKey(priv interface{}) interface{} {
diff --git a/libgo/go/crypto/tls/handshake_client.go b/libgo/go/crypto/tls/handshake_client.go
index 6eda18d..a4ca5d3 100644
--- a/libgo/go/crypto/tls/handshake_client.go
+++ b/libgo/go/crypto/tls/handshake_client.go
@@ -815,7 +815,7 @@
 	if net.ParseIP(host) != nil {
 		return ""
 	}
-	if len(name) > 0 && name[len(name)-1] == '.' {
+	for len(name) > 0 && name[len(name)-1] == '.' {
 		name = name[:len(name)-1]
 	}
 	return name
diff --git a/libgo/go/crypto/tls/handshake_messages.go b/libgo/go/crypto/tls/handshake_messages.go
index 694bd91..0c7581f 100644
--- a/libgo/go/crypto/tls/handshake_messages.go
+++ b/libgo/go/crypto/tls/handshake_messages.go
@@ -4,7 +4,10 @@
 
 package tls
 
-import "bytes"
+import (
+	"bytes"
+	"strings"
+)
 
 type clientHelloMsg struct {
 	raw                          []byte
@@ -393,6 +396,12 @@
 				}
 				if nameType == 0 {
 					m.serverName = string(d[:nameLen])
+					// An SNI value may not include a
+					// trailing dot. See
+					// https://tools.ietf.org/html/rfc6066#section-3.
+					if strings.HasSuffix(m.serverName, ".") {
+						return false
+					}
 					break
 				}
 				d = d[nameLen:]
diff --git a/libgo/go/crypto/tls/handshake_messages_test.go b/libgo/go/crypto/tls/handshake_messages_test.go
index f1154d4..7add97c 100644
--- a/libgo/go/crypto/tls/handshake_messages_test.go
+++ b/libgo/go/crypto/tls/handshake_messages_test.go
@@ -8,6 +8,7 @@
 	"bytes"
 	"math/rand"
 	"reflect"
+	"strings"
 	"testing"
 	"testing/quick"
 )
@@ -123,6 +124,9 @@
 	}
 	if rand.Intn(10) > 5 {
 		m.serverName = randomString(rand.Intn(255), rand)
+		for strings.HasSuffix(m.serverName, ".") {
+			m.serverName = m.serverName[:len(m.serverName)-1]
+		}
 	}
 	m.ocspStapling = rand.Intn(10) > 5
 	m.supportedPoints = randomBytes(rand.Intn(5)+1, rand)
diff --git a/libgo/go/crypto/tls/handshake_server.go b/libgo/go/crypto/tls/handshake_server.go
index b786c30..ae32848 100644
--- a/libgo/go/crypto/tls/handshake_server.go
+++ b/libgo/go/crypto/tls/handshake_server.go
@@ -40,7 +40,7 @@
 func (c *Conn) serverHandshake() error {
 	// If this is the first server handshake, we generate a random key to
 	// encrypt the tickets with.
-	c.config.serverInitOnce.Do(c.config.serverInit)
+	c.config.serverInitOnce.Do(func() { c.config.serverInit(nil) })
 
 	hs := serverHandshakeState{
 		c: c,
@@ -129,11 +129,7 @@
 			c.sendAlert(alertInternalError)
 			return false, err
 		} else if newConfig != nil {
-			newConfig.mutex.Lock()
-			newConfig.originalConfig = c.config
-			newConfig.mutex.Unlock()
-
-			newConfig.serverInitOnce.Do(newConfig.serverInit)
+			newConfig.serverInitOnce.Do(func() { newConfig.serverInit(c.config) })
 			c.config = newConfig
 		}
 	}
diff --git a/libgo/go/crypto/tls/handshake_server_test.go b/libgo/go/crypto/tls/handshake_server_test.go
index bcd3d43..63845c1 100644
--- a/libgo/go/crypto/tls/handshake_server_test.go
+++ b/libgo/go/crypto/tls/handshake_server_test.go
@@ -137,6 +137,10 @@
 	testClientHelloFailure(t, serverConfig, clientHello, "no cipher suite supported by both client and server")
 }
 
+func TestRejectSNIWithTrailingDot(t *testing.T) {
+	testClientHelloFailure(t, testConfig, &clientHelloMsg{vers: VersionTLS12, serverName: "foo.com."}, "unexpected message")
+}
+
 func TestDontSelectECDSAWithRSAKey(t *testing.T) {
 	// Test that, even when both sides support an ECDSA cipher suite, it
 	// won't be selected if the server's private key doesn't support it.
diff --git a/libgo/go/crypto/x509/pkcs1.go b/libgo/go/crypto/x509/pkcs1.go
index df20a44..73bc762 100644
--- a/libgo/go/crypto/x509/pkcs1.go
+++ b/libgo/go/crypto/x509/pkcs1.go
@@ -35,6 +35,12 @@
 	Coeff *big.Int
 }
 
+// pkcs1PublicKey reflects the ASN.1 structure of a PKCS#1 public key.
+type pkcs1PublicKey struct {
+	N *big.Int
+	E int
+}
+
 // ParsePKCS1PrivateKey returns an RSA private key from its ASN.1 PKCS#1 DER encoded form.
 func ParsePKCS1PrivateKey(der []byte) (*rsa.PrivateKey, error) {
 	var priv pkcs1PrivateKey
@@ -113,9 +119,3 @@
 	b, _ := asn1.Marshal(priv)
 	return b
 }
-
-// rsaPublicKey reflects the ASN.1 structure of a PKCS#1 public key.
-type rsaPublicKey struct {
-	N *big.Int
-	E int
-}
diff --git a/libgo/go/crypto/x509/root_bsd.go b/libgo/go/crypto/x509/root_bsd.go
index 9317283..1371933 100644
--- a/libgo/go/crypto/x509/root_bsd.go
+++ b/libgo/go/crypto/x509/root_bsd.go
@@ -8,7 +8,8 @@
 
 // Possible certificate files; stop after finding one.
 var certFiles = []string{
-	"/usr/local/share/certs/ca-root-nss.crt", // FreeBSD/DragonFly
+	"/usr/local/etc/ssl/cert.pem",            // FreeBSD
 	"/etc/ssl/cert.pem",                      // OpenBSD
+	"/usr/local/share/certs/ca-root-nss.crt", // DragonFly
 	"/etc/openssl/certs/ca-certificates.crt", // NetBSD
 }
diff --git a/libgo/go/crypto/x509/root_darwin.go b/libgo/go/crypto/x509/root_darwin.go
index 66cdb5e..bc35a1c 100644
--- a/libgo/go/crypto/x509/root_darwin.go
+++ b/libgo/go/crypto/x509/root_darwin.go
@@ -16,6 +16,7 @@
 	"io/ioutil"
 	"os"
 	"os/exec"
+	"os/user"
 	"path/filepath"
 	"strings"
 	"sync"
@@ -61,7 +62,26 @@
 		println(fmt.Sprintf("crypto/x509: %d certs have a trust policy", len(hasPolicy)))
 	}
 
-	cmd := exec.Command("/usr/bin/security", "find-certificate", "-a", "-p", "/System/Library/Keychains/SystemRootCertificates.keychain")
+	args := []string{"find-certificate", "-a", "-p",
+		"/System/Library/Keychains/SystemRootCertificates.keychain",
+		"/Library/Keychains/System.keychain",
+	}
+
+	u, err := user.Current()
+	if err != nil {
+		if debugExecDarwinRoots {
+			println(fmt.Sprintf("crypto/x509: get current user: %v", err))
+		}
+	} else {
+		args = append(args,
+			filepath.Join(u.HomeDir, "/Library/Keychains/login.keychain"),
+
+			// Fresh installs of Sierra use a slightly different path for the login keychain
+			filepath.Join(u.HomeDir, "/Library/Keychains/login.keychain-db"),
+		)
+	}
+
+	cmd := exec.Command("/usr/bin/security", args...)
 	data, err := cmd.Output()
 	if err != nil {
 		return nil, err
diff --git a/libgo/go/crypto/x509/root_unix.go b/libgo/go/crypto/x509/root_unix.go
index c44a524..0547460 100644
--- a/libgo/go/crypto/x509/root_unix.go
+++ b/libgo/go/crypto/x509/root_unix.go
@@ -16,28 +16,52 @@
 var certDirectories = []string{
 	"/etc/ssl/certs",               // SLES10/SLES11, https://golang.org/issue/12139
 	"/system/etc/security/cacerts", // Android
+	"/usr/local/share/certs",       // FreeBSD
+	"/etc/pki/tls/certs",           // Fedora/RHEL
+	"/etc/openssl/certs",           // NetBSD
 	"/var/ssl/certs",               // AIX
 }
 
+const (
+	// certFileEnv is the environment variable which identifies where to locate
+	// the SSL certificate file. If set this overrides the system default.
+	certFileEnv = "SSL_CERT_FILE"
+
+	// certDirEnv is the environment variable which identifies which directory
+	// to check for SSL certificate files. If set this overrides the system default.
+	certDirEnv = "SSL_CERT_DIR"
+)
+
 func (c *Certificate) systemVerify(opts *VerifyOptions) (chains [][]*Certificate, err error) {
 	return nil, nil
 }
 
 func loadSystemRoots() (*CertPool, error) {
 	roots := NewCertPool()
+
+	files := certFiles
+	if f := os.Getenv(certFileEnv); f != "" {
+		files = []string{f}
+	}
+
 	var firstErr error
-	for _, file := range certFiles {
+	for _, file := range files {
 		data, err := ioutil.ReadFile(file)
 		if err == nil {
 			roots.AppendCertsFromPEM(data)
-			return roots, nil
+			break
 		}
 		if firstErr == nil && !os.IsNotExist(err) {
 			firstErr = err
 		}
 	}
 
-	for _, directory := range certDirectories {
+	dirs := certDirectories
+	if d := os.Getenv(certDirEnv); d != "" {
+		dirs = []string{d}
+	}
+
+	for _, directory := range dirs {
 		fis, err := ioutil.ReadDir(directory)
 		if err != nil {
 			if firstErr == nil && !os.IsNotExist(err) {
@@ -57,5 +81,9 @@
 		}
 	}
 
+	if len(roots.certs) > 0 {
+		return roots, nil
+	}
+
 	return nil, firstErr
 }
diff --git a/libgo/go/crypto/x509/root_unix_test.go b/libgo/go/crypto/x509/root_unix_test.go
new file mode 100644
index 0000000..03f935d
--- /dev/null
+++ b/libgo/go/crypto/x509/root_unix_test.go
@@ -0,0 +1,127 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build dragonfly freebsd linux netbsd openbsd solaris
+
+package x509
+
+import (
+	"fmt"
+	"os"
+	"testing"
+)
+
+const (
+	testDir     = "testdata"
+	testDirCN   = "test-dir"
+	testFile    = "test-file.crt"
+	testFileCN  = "test-file"
+	testMissing = "missing"
+)
+
+func TestEnvVars(t *testing.T) {
+	testCases := []struct {
+		name    string
+		fileEnv string
+		dirEnv  string
+		files   []string
+		dirs    []string
+		cns     []string
+	}{
+		{
+			// Environment variables override the default locations preventing fall through.
+			name:    "override-defaults",
+			fileEnv: testMissing,
+			dirEnv:  testMissing,
+			files:   []string{testFile},
+			dirs:    []string{testDir},
+			cns:     nil,
+		},
+		{
+			// File environment overrides default file locations.
+			name:    "file",
+			fileEnv: testFile,
+			dirEnv:  "",
+			files:   nil,
+			dirs:    nil,
+			cns:     []string{testFileCN},
+		},
+		{
+			// Directory environment overrides default directory locations.
+			name:    "dir",
+			fileEnv: "",
+			dirEnv:  testDir,
+			files:   nil,
+			dirs:    nil,
+			cns:     []string{testDirCN},
+		},
+		{
+			// File & directory environment overrides both default locations.
+			name:    "file+dir",
+			fileEnv: testFile,
+			dirEnv:  testDir,
+			files:   nil,
+			dirs:    nil,
+			cns:     []string{testFileCN, testDirCN},
+		},
+		{
+			// Environment variable empty / unset uses default locations.
+			name:    "empty-fall-through",
+			fileEnv: "",
+			dirEnv:  "",
+			files:   []string{testFile},
+			dirs:    []string{testDir},
+			cns:     []string{testFileCN, testDirCN},
+		},
+	}
+
+	// Save old settings so we can restore before the test ends.
+	origCertFiles, origCertDirectories := certFiles, certDirectories
+	origFile, origDir := os.Getenv(certFileEnv), os.Getenv(certDirEnv)
+	defer func() {
+		certFiles = origCertFiles
+		certDirectories = origCertDirectories
+		os.Setenv(certFileEnv, origFile)
+		os.Setenv(certDirEnv, origDir)
+	}()
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			if err := os.Setenv(certFileEnv, tc.fileEnv); err != nil {
+				t.Fatalf("setenv %q failed: %v", certFileEnv, err)
+			}
+			if err := os.Setenv(certDirEnv, tc.dirEnv); err != nil {
+				t.Fatalf("setenv %q failed: %v", certDirEnv, err)
+			}
+
+			certFiles, certDirectories = tc.files, tc.dirs
+
+			r, err := loadSystemRoots()
+			if err != nil {
+				t.Fatal("unexpected failure:", err)
+			}
+
+			if r == nil {
+				if tc.cns == nil {
+					// Expected nil
+					return
+				}
+				t.Fatal("nil roots")
+			}
+
+			// Verify that the returned certs match, otherwise report where the mismatch is.
+			for i, cn := range tc.cns {
+				if i >= len(r.certs) {
+					t.Errorf("missing cert %v @ %v", cn, i)
+				} else if r.certs[i].Subject.CommonName != cn {
+					fmt.Printf("%#v\n", r.certs[0].Subject)
+					t.Errorf("unexpected cert common name %q, want %q", r.certs[i].Subject.CommonName, cn)
+				}
+			}
+			if len(r.certs) > len(tc.cns) {
+				t.Errorf("got %v certs, which is more than %v wanted", len(r.certs), len(tc.cns))
+			}
+		})
+	}
+}
diff --git a/libgo/go/crypto/x509/test-file.crt b/libgo/go/crypto/x509/test-file.crt
new file mode 100644
index 0000000..caa83b9
--- /dev/null
+++ b/libgo/go/crypto/x509/test-file.crt
@@ -0,0 +1,32 @@
+-----BEGIN CERTIFICATE-----
+MIIFbTCCA1WgAwIBAgIJAN338vEmMtLsMA0GCSqGSIb3DQEBCwUAME0xCzAJBgNV
+BAYTAlVLMRMwEQYDVQQIDApUZXN0LVN0YXRlMRUwEwYDVQQKDAxHb2xhbmcgVGVz
+dHMxEjAQBgNVBAMMCXRlc3QtZmlsZTAeFw0xNzAyMDEyMzUyMDhaFw0yNzAxMzAy
+MzUyMDhaME0xCzAJBgNVBAYTAlVLMRMwEQYDVQQIDApUZXN0LVN0YXRlMRUwEwYD
+VQQKDAxHb2xhbmcgVGVzdHMxEjAQBgNVBAMMCXRlc3QtZmlsZTCCAiIwDQYJKoZI
+hvcNAQEBBQADggIPADCCAgoCggIBAPMGiLjdiffQo3Xc8oUe7wsDhSaAJFOhO6Qs
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+CSqGSIb3DQEBCwUAA4ICAQB3sCntCcQwhMgRPPyvOCMyTcQ/Iv+cpfxz2Ck14nlx
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+pbdLwmBZB/v8V+6jUajy6jOgdSH0PyffGnt7MWgDETmNC6p/Xigp5eh+C8Fb4NGT
+xgHES5PBC+sruWp4u22bJGDKTvYNdZHsnw/CaKQWNsQqwisxa3/8N5v+PCff/pxl
+r05pE3PdHn9JrCl4iWdVlgtiI9BoPtQyDfa/OEFaScE8KYR8LxaAgdgp3zYncWls
+BpwQ6Y/A2wIkhlD9eEp5Ib2hz7isXOs9UwjdriKqrBXqcIAE5M+YIk3+KAQKxAtd
+4YsK3CSJ010uphr12YKqlScj4vuKFjuOtd5RyyMIxUG3lrrhAu2AzCeKCLdVgA8+
+75FrYMApUdvcjp4uzbBoED4XRQlx9kdFHVbYgmE/+yddBYJM8u4YlgAL0hW2/D8p
+z9JWIfxVmjJnBnXaKGBuiUyZ864A3PJndP6EMMo7TzS2CDnfCYuJjvI0KvDjFNmc
+rQA04+qfMSEz3nmKhbbZu4eYLzlADhfH8tT4GMtXf71WLA5AUHGf2Y4+HIHTsmHG
+vQ==
+-----END CERTIFICATE-----
diff --git a/libgo/go/crypto/x509/testdata/test-dir.crt b/libgo/go/crypto/x509/testdata/test-dir.crt
new file mode 100644
index 0000000..b7fc9c5
--- /dev/null
+++ b/libgo/go/crypto/x509/testdata/test-dir.crt
@@ -0,0 +1,31 @@
+-----BEGIN CERTIFICATE-----
+MIIFazCCA1OgAwIBAgIJAL8a/lsnspOqMA0GCSqGSIb3DQEBCwUAMEwxCzAJBgNV
+BAYTAlVLMRMwEQYDVQQIDApUZXN0LVN0YXRlMRUwEwYDVQQKDAxHb2xhbmcgVGVz
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+Xlxc/qijM8set/nOqp7hVd5J0uG6qdwLRILUddZ6OpXd7ZNi1EXg+Bpc7ehzGsDt
+3UFGzYXDjxYnK2frQfjLS8stOQIqSrGthW6x0fdkVx0y8BByvd5J6+JmZl4UZfzA
+m99VxXSt4B9x6BvnY7ktzcFDOjtuLc4B/7yg9fv1eQuStA4cHGGAttsCg1X/Kx8W
+PvkkeH0UWDZ9vhH9K36703z89da6MWF+bz92B0+4HoOmlVaXRkvblsNaynJnL0LC
+Ayry7QBxuh5cMnDdRwJB3AVJIiJ1GVpb7aGvBOnx+s2lwRv9HWtghb+cbwwktx1M
+JHyBf3GZNSWTpKY7cD8V+NnBv3UuioOVVo+XAU4LF/bYUjdRpxWADJizNtZrtFo=
+-----END CERTIFICATE-----
diff --git a/libgo/go/crypto/x509/verify.go b/libgo/go/crypto/x509/verify.go
index 29345a1..2b4f39d 100644
--- a/libgo/go/crypto/x509/verify.go
+++ b/libgo/go/crypto/x509/verify.go
@@ -87,7 +87,7 @@
 			valid += san.String()
 		}
 	} else {
-		if len(c.DNSNames) > 0 {
+		if c.hasSANExtension() {
 			valid = strings.Join(c.DNSNames, ", ")
 		} else {
 			valid = c.Subject.CommonName
@@ -166,7 +166,7 @@
 
 func matchNameConstraint(domain, constraint string) bool {
 	// The meaning of zero length constraints is not specified, but this
-	// code follows NSS and accepts them as valid for everything.
+	// code follows NSS and accepts them as matching everything.
 	if len(constraint) == 0 {
 		return true
 	}
@@ -220,6 +220,12 @@
 		}
 	}
 
+	for _, constraint := range c.ExcludedDNSDomains {
+		if matchNameConstraint(opts.DNSName, constraint) {
+			return CertificateInvalidError{c, CANotAuthorizedForThisName}
+		}
+	}
+
 	// KeyUsage status flags are ignored. From Engineering Security, Peter
 	// Gutmann: A European government CA marked its signing certificates as
 	// being valid for encryption only, but no-one noticed. Another
@@ -482,7 +488,7 @@
 
 	lowered := toLowerCaseASCII(h)
 
-	if len(c.DNSNames) > 0 {
+	if c.hasSANExtension() {
 		for _, match := range c.DNSNames {
 			if matchHostnames(toLowerCaseASCII(match), lowered) {
 				return nil
diff --git a/libgo/go/crypto/x509/verify_test.go b/libgo/go/crypto/x509/verify_test.go
index 15c4091..335c477 100644
--- a/libgo/go/crypto/x509/verify_test.go
+++ b/libgo/go/crypto/x509/verify_test.go
@@ -263,6 +263,39 @@
 
 		errorCallback: expectSubjectIssuerMismatcthError,
 	},
+	{
+		// An X.509 v1 certificate should not be accepted as an
+		// intermediate.
+		leaf:          x509v1TestLeaf,
+		intermediates: []string{x509v1TestIntermediate},
+		roots:         []string{x509v1TestRoot},
+		currentTime:   1481753183,
+		systemSkip:    true,
+
+		errorCallback: expectNotAuthorizedError,
+	},
+	{
+		// If any SAN extension is present (even one without any DNS
+		// names), the CN should be ignored.
+		leaf:        ignoreCNWithSANLeaf,
+		dnsName:     "foo.example.com",
+		roots:       []string{ignoreCNWithSANRoot},
+		currentTime: 1486684488,
+		systemSkip:  true,
+
+		errorCallback: expectHostnameError,
+	},
+	{
+		// Test that excluded names are respected.
+		leaf:          excludedNamesLeaf,
+		dnsName:       "bender.local",
+		intermediates: []string{excludedNamesIntermediate},
+		roots:         []string{excludedNamesRoot},
+		currentTime:   1486684488,
+		systemSkip:    true,
+
+		errorCallback: expectNameConstraintsError,
+	},
 }
 
 func expectHostnameError(t *testing.T, i int, err error) (ok bool) {
@@ -330,6 +363,22 @@
 	return true
 }
 
+func expectNameConstraintsError(t *testing.T, i int, err error) (ok bool) {
+	if inval, ok := err.(CertificateInvalidError); !ok || inval.Reason != CANotAuthorizedForThisName {
+		t.Errorf("#%d: error was not a CANotAuthorizedForThisName: %s", i, err)
+		return false
+	}
+	return true
+}
+
+func expectNotAuthorizedError(t *testing.T, i int, err error) (ok bool) {
+	if inval, ok := err.(CertificateInvalidError); !ok || inval.Reason != NotAuthorizedToSign {
+		t.Errorf("#%d: error was not a NotAuthorizedToSign: %s", i, err)
+		return false
+	}
+	return true
+}
+
 func certificateFromPEM(pemBytes string) (*Certificate, error) {
 	block, _ := pem.Decode([]byte(pemBytes))
 	if block == nil {
@@ -1269,6 +1318,174 @@
 -----END CERTIFICATE-----
 `
 
+const x509v1TestRoot = `
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+const x509v1TestIntermediate = `
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+const x509v1TestLeaf = `
+-----BEGIN CERTIFICATE-----
+MIICMzCCAZygAwIBAgIJAPo99mqJJrpJMA0GCSqGSIb3DQEBCwUAMDAxDzANBgNV
+BAoTBkdvbGFuZzEdMBsGA1UEAxMUWC41MDl2MSBpbnRlcm1lZGlhdGUwHhcNMTUw
+MTAxMDAwMDAwWhcNMjUwMTAxMDAwMDAwWjArMQ8wDQYDVQQKEwZHb2xhbmcxGDAW
+BgNVBAMTD2Zvby5leGFtcGxlLmNvbTCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkC
+gYEApUh60Z+a5/oKJxG//Dn8CihSo2CJHNIIO3zEJZ1EeNSMZCynaIR6D3IPZEIR
++RG2oGt+f5EEukAPYxwasp6VeZEezoQWJ+97nPCT6DpwLlWp3i2MF8piK2R9vxkG
+Z5n0+HzYk1VM8epIrZFUXSMGTX8w1y041PX/yYLxbdEifdcCAwEAAaNaMFgwDgYD
+VR0PAQH/BAQDAgWgMB0GA1UdJQQWMBQGCCsGAQUFBwMBBggrBgEFBQcDAjAMBgNV
+HRMBAf8EAjAAMBkGA1UdDgQSBBBFozXe0SnzAmjy+1U6M/cvMA0GCSqGSIb3DQEB
+CwUAA4GBADYzYUvaToO/ucBskPdqXV16AaakIhhSENswYVSl97/sODaxsjishKq9
+5R7siu+JnIFotA7IbBe633p75xEnLN88X626N/XRFG9iScLzpj0o0PWXBUiB+fxL
+/jt8qszOXCv2vYdUTPNuPqufXLWMoirpuXrr1liJDmedCcAHepY/
+-----END CERTIFICATE-----`
+
+const ignoreCNWithSANRoot = `
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+const ignoreCNWithSANLeaf = `
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+const excludedNamesLeaf = `
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+`
+
+const excludedNamesIntermediate = `
+-----BEGIN CERTIFICATE-----
+MIIDzTCCArWgAwIBAgIHDUSFqYeczDANBgkqhkiG9w0BAQsFADCBmTELMAkGA1UE
+BhMCVVMxEzARBgNVBAgMCkNhbGlmb3JuaWExEjAQBgNVBAcMCUxvcyBHYXRvczEU
+MBIGA1UECgwLTmV0ZmxpeCBJbmMxLTArBgNVBAsMJFBsYXRmb3JtIFNlY3VyaXR5
+ICgzNzM0NTE1NDc5MDY0NjAyKTEcMBoGA1UEAwwTTG9jYWwgUm9vdCBmb3IgMzM5
+MjAeFw0xNzAyMDgyMTE1MDRaFw0xODAyMDgyMDI0NThaMIGeMQswCQYDVQQGEwJV
+UzETMBEGA1UECAwKQ2FsaWZvcm5pYTESMBAGA1UEBwwJTG9zIEdhdG9zMRQwEgYD
+VQQKDAtOZXRmbGl4IEluYzEtMCsGA1UECwwkUGxhdGZvcm0gU2VjdXJpdHkgKDM3
+MzQ1MTU1NjI4MDYzOTcpMSEwHwYDVQQDDBhJbnRlcm1lZGlhdGUgQ0EgZm9yIDMz
+OTIwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQCOyEs6tJ/t9emQTvlx
+3FS7uJSou5rKkuqVxZdIuYQ+B2ZviBYUnMRT9bXDB0nsVdKZdp0hdchdiwNXDG/I
+CiWu48jkcv/BdynVyayOT+0pOJSYLaPYpzBx1Pb9M5651ct9GSbj6Tz0ChVonoIE
+1AIZ0kkebucZRRFHd0xbAKVRKyUzPN6HJ7WfgyauUp7RmlC35wTmrmARrFohQLlL
+7oICy+hIQePMy9x1LSFTbPxZ5AUUXVC3eUACU3vLClF/Xs8XGHebZpUXCdMQjOGS
+nq1eFguFHR1poSB8uSmmLqm4vqUH9CDhEgiBAC8yekJ8//kZQ7lUEqZj3YxVbk+Y
+E4H5AgMBAAGjEzARMA8GA1UdEwEB/wQFMAMBAf8wDQYJKoZIhvcNAQELBQADggEB
+ADxrnmNX5gWChgX9K5fYwhFDj5ofxZXAKVQk+WjmkwMcmCx3dtWSm++Wdksj/ZlA
+V1cLW3ohWv1/OAZuOlw7sLf98aJpX+UUmIYYQxDubq+4/q7VA7HzEf2k/i/oN1NI
+JgtrhpPcZ/LMO6k7DYx0qlfYq8pTSfd6MI4LnWKgLc+JSPJJjmvspgio2ZFcnYr7
+A264BwLo6v1Mos1o1JUvFFcp4GANlw0XFiWh7JXYRl8WmS5DoouUC+aNJ3lmyF6z
+LbIjZCSfgZnk/LK1KU1j91FI2bc2ULYZvAC1PAg8/zvIgxn6YM2Q7ZsdEgWw0FpS
+zMBX1/lk4wkFckeUIlkD55Y=
+-----END CERTIFICATE-----`
+
+const excludedNamesRoot = `
+-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`
+
 var unknownAuthorityErrorTests = []struct {
 	cert     string
 	expected string
@@ -1294,7 +1511,7 @@
 			hintCert: c,
 		}
 		actual := uae.Error()
-		if strings.Compare(actual, tt.expected) != 0 {
+		if actual != tt.expected {
 			t.Errorf("#%d: UnknownAuthorityError.Error() response invalid actual: %s expected: %s", i, actual, tt.expected)
 		}
 	}
diff --git a/libgo/go/crypto/x509/x509.go b/libgo/go/crypto/x509/x509.go
index 949ce01..fdc7c53 100644
--- a/libgo/go/crypto/x509/x509.go
+++ b/libgo/go/crypto/x509/x509.go
@@ -3,6 +3,10 @@
 // license that can be found in the LICENSE file.
 
 // Package x509 parses X.509-encoded keys and certificates.
+//
+// On UNIX systems the environment variables SSL_CERT_FILE and SSL_CERT_DIR
+// can be used to override the system default locations for the SSL certificate
+// file and SSL certificate files directory, respectively.
 package x509
 
 import (
@@ -59,7 +63,7 @@
 func marshalPublicKey(pub interface{}) (publicKeyBytes []byte, publicKeyAlgorithm pkix.AlgorithmIdentifier, err error) {
 	switch pub := pub.(type) {
 	case *rsa.PublicKey:
-		publicKeyBytes, err = asn1.Marshal(rsaPublicKey{
+		publicKeyBytes, err = asn1.Marshal(pkcs1PublicKey{
 			N: pub.N,
 			E: pub.E,
 		})
@@ -69,9 +73,7 @@
 		publicKeyAlgorithm.Algorithm = oidPublicKeyRSA
 		// This is a NULL parameters value which is required by
 		// https://tools.ietf.org/html/rfc3279#section-2.3.1.
-		publicKeyAlgorithm.Parameters = asn1.RawValue{
-			Tag: 5,
-		}
+		publicKeyAlgorithm.Parameters = asn1.NullRawValue
 	case *ecdsa.PublicKey:
 		publicKeyBytes = elliptic.Marshal(pub.Curve, pub.X, pub.Y)
 		oid, ok := oidFromNamedCurve(pub.Curve)
@@ -355,10 +357,8 @@
 
 	params := pssParameters{
 		Hash: pkix.AlgorithmIdentifier{
-			Algorithm: hashOID,
-			Parameters: asn1.RawValue{
-				Tag: 5, /* ASN.1 NULL */
-			},
+			Algorithm:  hashOID,
+			Parameters: asn1.NullRawValue,
 		},
 		MGF: pkix.AlgorithmIdentifier{
 			Algorithm: oidMGF1,
@@ -368,10 +368,8 @@
 	}
 
 	mgf1Params := pkix.AlgorithmIdentifier{
-		Algorithm: hashOID,
-		Parameters: asn1.RawValue{
-			Tag: 5, /* ASN.1 NULL */
-		},
+		Algorithm:  hashOID,
+		Parameters: asn1.NullRawValue,
 	}
 
 	var err error
@@ -418,11 +416,10 @@
 	// https://tools.ietf.org/html/rfc3447#section-8.1), that the
 	// salt length matches the hash length, and that the trailer
 	// field has the default value.
-	asn1NULL := []byte{0x05, 0x00}
-	if !bytes.Equal(params.Hash.Parameters.FullBytes, asn1NULL) ||
+	if !bytes.Equal(params.Hash.Parameters.FullBytes, asn1.NullBytes) ||
 		!params.MGF.Algorithm.Equal(oidMGF1) ||
 		!mgf1HashFunc.Algorithm.Equal(params.Hash.Algorithm) ||
-		!bytes.Equal(mgf1HashFunc.Parameters.FullBytes, asn1NULL) ||
+		!bytes.Equal(mgf1HashFunc.Parameters.FullBytes, asn1.NullBytes) ||
 		params.TrailerField != 1 {
 		return UnknownSignatureAlgorithm
 	}
@@ -668,13 +665,28 @@
 	ExtKeyUsage        []ExtKeyUsage           // Sequence of extended key usages.
 	UnknownExtKeyUsage []asn1.ObjectIdentifier // Encountered extended key usages unknown to this package.
 
-	BasicConstraintsValid bool // if true then the next two fields are valid.
+	// BasicConstraintsValid indicates whether IsCA, MaxPathLen,
+	// and MaxPathLenZero are valid.
+	BasicConstraintsValid bool
 	IsCA                  bool
-	MaxPathLen            int
-	// MaxPathLenZero indicates that BasicConstraintsValid==true and
-	// MaxPathLen==0 should be interpreted as an actual maximum path length
-	// of zero. Otherwise, that combination is interpreted as MaxPathLen
-	// not being set.
+
+	// MaxPathLen and MaxPathLenZero indicate the presence and
+	// value of the BasicConstraints' "pathLenConstraint".
+	//
+	// When parsing a certificate, a positive non-zero MaxPathLen
+	// means that the field was specified, -1 means it was unset,
+	// and MaxPathLenZero being true mean that the field was
+	// explicitly set to zero. The case of MaxPathLen==0 with MaxPathLenZero==false
+	// should be treated equivalent to -1 (unset).
+	//
+	// When generating a certificate, an unset pathLenConstraint
+	// can be requested with either MaxPathLen == -1 or using the
+	// zero value for both MaxPathLen and MaxPathLenZero.
+	MaxPathLen int
+	// MaxPathLenZero indicates that BasicConstraintsValid==true
+	// and MaxPathLen==0 should be interpreted as an actual
+	// maximum path length of zero. Otherwise, that combination is
+	// interpreted as MaxPathLen not being set.
 	MaxPathLenZero bool
 
 	SubjectKeyId   []byte
@@ -692,6 +704,7 @@
 	// Name constraints
 	PermittedDNSDomainsCritical bool // if true then the name constraints are marked critical.
 	PermittedDNSDomains         []string
+	ExcludedDNSDomains          []string
 
 	// CRL Distribution Points
 	CRLDistributionPoints []string
@@ -723,6 +736,10 @@
 	return bytes.Equal(c.Raw, other.Raw)
 }
 
+func (c *Certificate) hasSANExtension() bool {
+	return oidInExtensions(oidExtensionSubjectAltName, c.Extensions)
+}
+
 // Entrust have a broken root certificate (CN=Entrust.net Certification
 // Authority (2048)) which isn't marked as a CA certificate and is thus invalid
 // according to PKIX.
@@ -924,20 +941,17 @@
 	RelativeName pkix.RDNSequence `asn1:"optional,tag:1"`
 }
 
-// asn1Null is the ASN.1 encoding of a NULL value.
-var asn1Null = []byte{5, 0}
-
 func parsePublicKey(algo PublicKeyAlgorithm, keyData *publicKeyInfo) (interface{}, error) {
 	asn1Data := keyData.PublicKey.RightAlign()
 	switch algo {
 	case RSA:
 		// RSA public keys must have a NULL in the parameters
 		// (https://tools.ietf.org/html/rfc3279#section-2.3.1).
-		if !bytes.Equal(keyData.Algorithm.Parameters.FullBytes, asn1Null) {
+		if !bytes.Equal(keyData.Algorithm.Parameters.FullBytes, asn1.NullBytes) {
 			return nil, errors.New("x509: RSA key missing NULL parameters")
 		}
 
-		p := new(rsaPublicKey)
+		p := new(pkcs1PublicKey)
 		rest, err := asn1.Unmarshal(asn1Data, p)
 		if err != nil {
 			return nil, err
@@ -1150,7 +1164,7 @@
 				out.IsCA = constraints.IsCA
 				out.MaxPathLen = constraints.MaxPathLen
 				out.MaxPathLenZero = out.MaxPathLen == 0
-
+				// TODO: map out.MaxPathLen to 0 if it has the -1 default value? (Issue 19285)
 			case 17:
 				out.DNSNames, out.EmailAddresses, out.IPAddresses, err = parseSANExtension(e.Value)
 				if err != nil {
@@ -1185,19 +1199,27 @@
 					return nil, errors.New("x509: trailing data after X.509 NameConstraints")
 				}
 
-				if len(constraints.Excluded) > 0 && e.Critical {
-					return out, UnhandledCriticalExtension{}
+				getDNSNames := func(subtrees []generalSubtree, isCritical bool) (dnsNames []string, err error) {
+					for _, subtree := range subtrees {
+						if len(subtree.Name) == 0 {
+							if isCritical {
+								return nil, UnhandledCriticalExtension{}
+							}
+							continue
+						}
+						dnsNames = append(dnsNames, subtree.Name)
+					}
+
+					return dnsNames, nil
 				}
 
-				for _, subtree := range constraints.Permitted {
-					if len(subtree.Name) == 0 {
-						if e.Critical {
-							return out, UnhandledCriticalExtension{}
-						}
-						continue
-					}
-					out.PermittedDNSDomains = append(out.PermittedDNSDomains, subtree.Name)
+				if out.PermittedDNSDomains, err = getDNSNames(constraints.Permitted, e.Critical); err != nil {
+					return out, err
 				}
+				if out.ExcludedDNSDomains, err = getDNSNames(constraints.Excluded, e.Critical); err != nil {
+					return out, err
+				}
+				out.PermittedDNSDomainsCritical = e.Critical
 
 			case 31:
 				// RFC 5280, 4.2.1.13
@@ -1451,7 +1473,7 @@
 	return asn1.Marshal(rawValues)
 }
 
-func buildExtensions(template *Certificate) (ret []pkix.Extension, err error) {
+func buildExtensions(template *Certificate, authorityKeyId []byte) (ret []pkix.Extension, err error) {
 	ret = make([]pkix.Extension, 10 /* maximum number of elements. */)
 	n := 0
 
@@ -1525,9 +1547,9 @@
 		n++
 	}
 
-	if len(template.AuthorityKeyId) > 0 && !oidInExtensions(oidExtensionAuthorityKeyId, template.ExtraExtensions) {
+	if len(authorityKeyId) > 0 && !oidInExtensions(oidExtensionAuthorityKeyId, template.ExtraExtensions) {
 		ret[n].Id = oidExtensionAuthorityKeyId
-		ret[n].Value, err = asn1.Marshal(authKeyId{template.AuthorityKeyId})
+		ret[n].Value, err = asn1.Marshal(authKeyId{authorityKeyId})
 		if err != nil {
 			return
 		}
@@ -1581,16 +1603,22 @@
 		n++
 	}
 
-	if len(template.PermittedDNSDomains) > 0 &&
+	if (len(template.PermittedDNSDomains) > 0 || len(template.ExcludedDNSDomains) > 0) &&
 		!oidInExtensions(oidExtensionNameConstraints, template.ExtraExtensions) {
 		ret[n].Id = oidExtensionNameConstraints
 		ret[n].Critical = template.PermittedDNSDomainsCritical
 
 		var out nameConstraints
+
 		out.Permitted = make([]generalSubtree, len(template.PermittedDNSDomains))
 		for i, permitted := range template.PermittedDNSDomains {
 			out.Permitted[i] = generalSubtree{Name: permitted}
 		}
+		out.Excluded = make([]generalSubtree, len(template.ExcludedDNSDomains))
+		for i, excluded := range template.ExcludedDNSDomains {
+			out.Excluded[i] = generalSubtree{Name: excluded}
+		}
+
 		ret[n].Value, err = asn1.Marshal(out)
 		if err != nil {
 			return
@@ -1646,9 +1674,7 @@
 		pubType = RSA
 		hashFunc = crypto.SHA256
 		sigAlgo.Algorithm = oidSignatureSHA256WithRSA
-		sigAlgo.Parameters = asn1.RawValue{
-			Tag: 5,
-		}
+		sigAlgo.Parameters = asn1.NullRawValue
 
 	case *ecdsa.PublicKey:
 		pubType = ECDSA
@@ -1706,11 +1732,12 @@
 	return
 }
 
-// CreateCertificate creates a new certificate based on a template. The
-// following members of template are used: SerialNumber, Subject, NotBefore,
-// NotAfter, KeyUsage, ExtKeyUsage, UnknownExtKeyUsage, BasicConstraintsValid,
-// IsCA, MaxPathLen, SubjectKeyId, DNSNames, PermittedDNSDomainsCritical,
-// PermittedDNSDomains, SignatureAlgorithm.
+// CreateCertificate creates a new certificate based on a template.
+// The following members of template are used: AuthorityKeyId,
+// BasicConstraintsValid, DNSNames, ExcludedDNSDomains, ExtKeyUsage,
+// IsCA, KeyUsage, MaxPathLen, MaxPathLenZero, NotAfter, NotBefore,
+// PermittedDNSDomains, PermittedDNSDomainsCritical, SerialNumber,
+// SignatureAlgorithm, Subject, SubjectKeyId, and UnknownExtKeyUsage.
 //
 // The certificate is signed by parent. If parent is equal to template then the
 // certificate is self-signed. The parameter pub is the public key of the
@@ -1720,6 +1747,10 @@
 //
 // All keys types that are implemented via crypto.Signer are supported (This
 // includes *rsa.PublicKey and *ecdsa.PublicKey.)
+//
+// The AuthorityKeyId will be taken from the SubjectKeyId of parent, if any,
+// unless the resulting certificate is self-signed. Otherwise the value from
+// template will be used.
 func CreateCertificate(rand io.Reader, template, parent *Certificate, pub, priv interface{}) (cert []byte, err error) {
 	key, ok := priv.(crypto.Signer)
 	if !ok {
@@ -1750,11 +1781,12 @@
 		return
 	}
 
+	authorityKeyId := template.AuthorityKeyId
 	if !bytes.Equal(asn1Issuer, asn1Subject) && len(parent.SubjectKeyId) > 0 {
-		template.AuthorityKeyId = parent.SubjectKeyId
+		authorityKeyId = parent.SubjectKeyId
 	}
 
-	extensions, err := buildExtensions(template)
+	extensions, err := buildExtensions(template, authorityKeyId)
 	if err != nil {
 		return
 	}
@@ -2025,10 +2057,10 @@
 	return ret, nil
 }
 
-// CreateCertificateRequest creates a new certificate request based on a template.
-// The following members of template are used: Subject, Attributes,
-// SignatureAlgorithm, Extensions, DNSNames, EmailAddresses, and IPAddresses.
-// The private key is the private key of the signer.
+// CreateCertificateRequest creates a new certificate request based on a
+// template. The following members of template are used: Attributes, DNSNames,
+// EmailAddresses, ExtraExtensions, IPAddresses, SignatureAlgorithm, and
+// Subject. The private key is the private key of the signer.
 //
 // The returned slice is the certificate request in DER encoding.
 //
diff --git a/libgo/go/crypto/x509/x509_test.go b/libgo/go/crypto/x509/x509_test.go
index b085dad..2d1acf9 100644
--- a/libgo/go/crypto/x509/x509_test.go
+++ b/libgo/go/crypto/x509/x509_test.go
@@ -405,6 +405,7 @@
 
 			PolicyIdentifiers:   []asn1.ObjectIdentifier{[]int{1, 2, 3}},
 			PermittedDNSDomains: []string{".example.com", "example.com"},
+			ExcludedDNSDomains:  []string{"bar.example.com"},
 
 			CRLDistributionPoints: []string{"http://crl1.example.com/ca1.crl", "http://crl2.example.com/ca1.crl"},
 
@@ -442,6 +443,10 @@
 			t.Errorf("%s: failed to parse name constraints: %#v", test.name, cert.PermittedDNSDomains)
 		}
 
+		if len(cert.ExcludedDNSDomains) != 1 || cert.ExcludedDNSDomains[0] != "bar.example.com" {
+			t.Errorf("%s: failed to parse name constraint exclusions: %#v", test.name, cert.ExcludedDNSDomains)
+		}
+
 		if cert.Subject.CommonName != commonName {
 			t.Errorf("%s: subject wasn't correctly copied from the template. Got %s, want %s", test.name, cert.Subject.CommonName, commonName)
 		}
diff --git a/libgo/go/database/sql/convert.go b/libgo/go/database/sql/convert.go
index ea2f377..4983181 100644
--- a/libgo/go/database/sql/convert.go
+++ b/libgo/go/database/sql/convert.go
@@ -12,6 +12,7 @@
 	"fmt"
 	"reflect"
 	"strconv"
+	"sync"
 	"time"
 	"unicode"
 	"unicode/utf8"
@@ -37,86 +38,180 @@
 	return fmt.Errorf("name %q does not begin with a letter", name)
 }
 
+func driverNumInput(ds *driverStmt) int {
+	ds.Lock()
+	defer ds.Unlock() // in case NumInput panics
+	return ds.si.NumInput()
+}
+
+// ccChecker wraps the driver.ColumnConverter and allows it to be used
+// as if it were a NamedValueChecker. If the driver ColumnConverter
+// is not present then the NamedValueChecker will return driver.ErrSkip.
+type ccChecker struct {
+	sync.Locker
+	cci  driver.ColumnConverter
+	want int
+}
+
+func (c ccChecker) CheckNamedValue(nv *driver.NamedValue) error {
+	if c.cci == nil {
+		return driver.ErrSkip
+	}
+	// The column converter shouldn't be called on any index
+	// it isn't expecting. The final error will be thrown
+	// in the argument converter loop.
+	index := nv.Ordinal - 1
+	if c.want <= index {
+		return nil
+	}
+
+	// First, see if the value itself knows how to convert
+	// itself to a driver type. For example, a NullString
+	// struct changing into a string or nil.
+	if vr, ok := nv.Value.(driver.Valuer); ok {
+		sv, err := callValuerValue(vr)
+		if err != nil {
+			return err
+		}
+		if !driver.IsValue(sv) {
+			return fmt.Errorf("non-subset type %T returned from Value", sv)
+		}
+		nv.Value = sv
+	}
+
+	// Second, ask the column to sanity check itself. For
+	// example, drivers might use this to make sure that
+	// an int64 values being inserted into a 16-bit
+	// integer field is in range (before getting
+	// truncated), or that a nil can't go into a NOT NULL
+	// column before going across the network to get the
+	// same error.
+	var err error
+	arg := nv.Value
+	c.Lock()
+	nv.Value, err = c.cci.ColumnConverter(index).ConvertValue(arg)
+	c.Unlock()
+	if err != nil {
+		return err
+	}
+	if !driver.IsValue(nv.Value) {
+		return fmt.Errorf("driver ColumnConverter error converted %T to unsupported type %T", arg, nv.Value)
+	}
+	return nil
+}
+
+// defaultCheckNamedValue wraps the default ColumnConverter to have the same
+// function signature as the CheckNamedValue in the driver.NamedValueChecker
+// interface.
+func defaultCheckNamedValue(nv *driver.NamedValue) (err error) {
+	nv.Value, err = driver.DefaultParameterConverter.ConvertValue(nv.Value)
+	return err
+}
+
 // driverArgs converts arguments from callers of Stmt.Exec and
 // Stmt.Query into driver Values.
 //
 // The statement ds may be nil, if no statement is available.
-func driverArgs(ds *driverStmt, args []interface{}) ([]driver.NamedValue, error) {
+func driverArgs(ci driver.Conn, ds *driverStmt, args []interface{}) ([]driver.NamedValue, error) {
 	nvargs := make([]driver.NamedValue, len(args))
+
+	// -1 means the driver doesn't know how to count the number of
+	// placeholders, so we won't sanity check input here and instead let the
+	// driver deal with errors.
+	want := -1
+
 	var si driver.Stmt
+	var cc ccChecker
 	if ds != nil {
 		si = ds.si
+		want = driverNumInput(ds)
+		cc.Locker = ds.Locker
+		cc.want = want
 	}
-	cc, ok := si.(driver.ColumnConverter)
 
-	// Normal path, for a driver.Stmt that is not a ColumnConverter.
+	// Check all types of interfaces from the start.
+	// Drivers may opt to use the NamedValueChecker for special
+	// argument types, then return driver.ErrSkip to pass it along
+	// to the column converter.
+	nvc, ok := si.(driver.NamedValueChecker)
 	if !ok {
-		for n, arg := range args {
-			var err error
-			nv := &nvargs[n]
-			nv.Ordinal = n + 1
-			if np, ok := arg.(NamedArg); ok {
-				if err := validateNamedValueName(np.Name); err != nil {
-					return nil, err
-				}
-				arg = np.Value
-				nvargs[n].Name = np.Name
-			}
-			nv.Value, err = driver.DefaultParameterConverter.ConvertValue(arg)
-
-			if err != nil {
-				return nil, fmt.Errorf("sql: converting Exec argument %s type: %v", describeNamedValue(nv), err)
-			}
-		}
-		return nvargs, nil
+		nvc, ok = ci.(driver.NamedValueChecker)
+	}
+	cci, ok := si.(driver.ColumnConverter)
+	if ok {
+		cc.cci = cci
 	}
 
-	// Let the Stmt convert its own arguments.
-	for n, arg := range args {
+	// Loop through all the arguments, checking each one.
+	// If no error is returned simply increment the index
+	// and continue. However if driver.ErrRemoveArgument
+	// is returned the argument is not included in the query
+	// argument list.
+	var err error
+	var n int
+	for _, arg := range args {
 		nv := &nvargs[n]
-		nv.Ordinal = n + 1
 		if np, ok := arg.(NamedArg); ok {
-			if err := validateNamedValueName(np.Name); err != nil {
+			if err = validateNamedValueName(np.Name); err != nil {
 				return nil, err
 			}
 			arg = np.Value
 			nv.Name = np.Name
 		}
-		// First, see if the value itself knows how to convert
-		// itself to a driver type. For example, a NullString
-		// struct changing into a string or nil.
-		if vr, ok := arg.(driver.Valuer); ok {
-			sv, err := callValuerValue(vr)
-			if err != nil {
-				return nil, fmt.Errorf("sql: argument %s from Value: %v", describeNamedValue(nv), err)
-			}
-			if !driver.IsValue(sv) {
-				return nil, fmt.Errorf("sql: argument %s: non-subset type %T returned from Value", describeNamedValue(nv), sv)
-			}
-			arg = sv
+		nv.Ordinal = n + 1
+		nv.Value = arg
+
+		// Checking sequence has four routes:
+		// A: 1. Default
+		// B: 1. NamedValueChecker 2. Column Converter 3. Default
+		// C: 1. NamedValueChecker 3. Default
+		// D: 1. Column Converter 2. Default
+		//
+		// The only time a Column Converter is called is first
+		// or after NamedValueConverter. If first it is handled before
+		// the nextCheck label. Thus for repeats tries only when the
+		// NamedValueConverter is selected should the Column Converter
+		// be used in the retry.
+		checker := defaultCheckNamedValue
+		nextCC := false
+		switch {
+		case nvc != nil:
+			nextCC = cci != nil
+			checker = nvc.CheckNamedValue
+		case cci != nil:
+			checker = cc.CheckNamedValue
 		}
 
-		// Second, ask the column to sanity check itself. For
-		// example, drivers might use this to make sure that
-		// an int64 values being inserted into a 16-bit
-		// integer field is in range (before getting
-		// truncated), or that a nil can't go into a NOT NULL
-		// column before going across the network to get the
-		// same error.
-		var err error
-		ds.Lock()
-		nv.Value, err = cc.ColumnConverter(n).ConvertValue(arg)
-		ds.Unlock()
-		if err != nil {
+	nextCheck:
+		err = checker(nv)
+		switch err {
+		case nil:
+			n++
+			continue
+		case driver.ErrRemoveArgument:
+			nvargs = nvargs[:len(nvargs)-1]
+			continue
+		case driver.ErrSkip:
+			if nextCC {
+				nextCC = false
+				checker = cc.CheckNamedValue
+			} else {
+				checker = defaultCheckNamedValue
+			}
+			goto nextCheck
+		default:
 			return nil, fmt.Errorf("sql: converting argument %s type: %v", describeNamedValue(nv), err)
 		}
-		if !driver.IsValue(nv.Value) {
-			return nil, fmt.Errorf("sql: for argument %s, driver ColumnConverter error converted %T to unsupported type %T",
-				describeNamedValue(nv), arg, nv.Value)
-		}
 	}
 
+	// Check the length of arguments after convertion to allow for omitted
+	// arguments.
+	if want != -1 && len(nvargs) != want {
+		return nil, fmt.Errorf("sql: expected %d arguments, got %d", want, len(nvargs))
+	}
+
 	return nvargs, nil
+
 }
 
 // convertAssign copies to dest the value in src, converting it if possible.
@@ -270,6 +365,11 @@
 		return nil
 	}
 
+	// The following conversions use a string value as an intermediate representation
+	// to convert between various numeric types.
+	//
+	// This also allows scanning into user defined types such as "type Int int64".
+	// For symmetry, also check for string destination types.
 	switch dv.Kind() {
 	case reflect.Ptr:
 		if src == nil {
@@ -306,6 +406,15 @@
 		}
 		dv.SetFloat(f64)
 		return nil
+	case reflect.String:
+		switch v := src.(type) {
+		case string:
+			dv.SetString(v)
+			return nil
+		case []byte:
+			dv.SetString(string(v))
+			return nil
+		}
 	}
 
 	return fmt.Errorf("unsupported Scan, storing driver.Value type %T into type %T", src, dest)
diff --git a/libgo/go/database/sql/convert_test.go b/libgo/go/database/sql/convert_test.go
index 4dfab1f..cfe52d7 100644
--- a/libgo/go/database/sql/convert_test.go
+++ b/libgo/go/database/sql/convert_test.go
@@ -10,6 +10,7 @@
 	"reflect"
 	"runtime"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 )
@@ -17,9 +18,11 @@
 var someTime = time.Unix(123, 0)
 var answer int64 = 42
 
-type userDefined float64
-
-type userDefinedSlice []int
+type (
+	userDefined       float64
+	userDefinedSlice  []int
+	userDefinedString string
+)
 
 type conversionTest struct {
 	s, d interface{} // source and destination
@@ -39,6 +42,7 @@
 	wantptr    *int64 // if non-nil, *d's pointed value must be equal to *wantptr
 	wantnil    bool   // if true, *d must be *int64(nil)
 	wantusrdef userDefined
+	wantusrstr userDefinedString
 }
 
 // Target variables for scanning into.
@@ -171,6 +175,7 @@
 	{s: int64(123), d: new(userDefined), wantusrdef: 123},
 	{s: "1.5", d: new(userDefined), wantusrdef: 1.5},
 	{s: []byte{1, 2, 3}, d: new(userDefinedSlice), wanterr: `unsupported Scan, storing driver.Value type []uint8 into type *sql.userDefinedSlice`},
+	{s: "str", d: new(userDefinedString), wantusrstr: "str"},
 
 	// Other errors
 	{s: complex(1, 2), d: &scanstr, wanterr: `unsupported Scan, storing driver.Value type complex128 into type *string`},
@@ -260,6 +265,9 @@
 		if ct.wantusrdef != 0 && ct.wantusrdef != *ct.d.(*userDefined) {
 			errf("want userDefined %f, got %f", ct.wantusrdef, *ct.d.(*userDefined))
 		}
+		if len(ct.wantusrstr) != 0 && ct.wantusrstr != *ct.d.(*userDefinedString) {
+			errf("want userDefined %q, got %q", ct.wantusrstr, *ct.d.(*userDefinedString))
+		}
 	}
 }
 
@@ -461,8 +469,8 @@
 		},
 	}
 	for i, tt := range tests {
-		ds := new(driverStmt)
-		got, err := driverArgs(ds, tt.args)
+		ds := &driverStmt{Locker: &sync.Mutex{}, si: stubDriverStmt{nil}}
+		got, err := driverArgs(nil, ds, tt.args)
 		if err != nil {
 			t.Errorf("test[%d]: %v", i, err)
 			continue
diff --git a/libgo/go/database/sql/driver/driver.go b/libgo/go/database/sql/driver/driver.go
index d66196f..0262ca2 100644
--- a/libgo/go/database/sql/driver/driver.go
+++ b/libgo/go/database/sql/driver/driver.go
@@ -262,9 +262,39 @@
 	QueryContext(ctx context.Context, args []NamedValue) (Rows, error)
 }
 
+// ErrRemoveArgument may be returned from NamedValueChecker to instruct the
+// sql package to not pass the argument to the driver query interface.
+// Return when accepting query specific options or structures that aren't
+// SQL query arguments.
+var ErrRemoveArgument = errors.New("driver: remove argument from query")
+
+// NamedValueChecker may be optionally implemented by Conn or Stmt. It provides
+// the driver more control to handle Go and database types beyond the default
+// Values types allowed.
+//
+// The sql package checks for value checkers in the following order,
+// stopping at the first found match: Stmt.NamedValueChecker, Conn.NamedValueChecker,
+// Stmt.ColumnConverter, DefaultParameterConverter.
+//
+// If CheckNamedValue returns ErrRemoveArgument, the NamedValue will not be included in
+// the final query arguments. This may be used to pass special options to
+// the query itself.
+//
+// If ErrSkip is returned the column converter error checking
+// path is used for the argument. Drivers may wish to return ErrSkip after
+// they have exhausted their own special cases.
+type NamedValueChecker interface {
+	// CheckNamedValue is called before passing arguments to the driver
+	// and is called in place of any ColumnConverter. CheckNamedValue must do type
+	// validation and conversion as appropriate for the driver.
+	CheckNamedValue(*NamedValue) error
+}
+
 // ColumnConverter may be optionally implemented by Stmt if the
 // statement is aware of its own columns' types and can convert from
 // any type to a driver Value.
+//
+// Deprecated: Drivers should implement NamedValueChecker.
 type ColumnConverter interface {
 	// ColumnConverter returns a ValueConverter for the provided
 	// column index. If the type of a specific column isn't known
diff --git a/libgo/go/database/sql/fakedb_test.go b/libgo/go/database/sql/fakedb_test.go
index 4b15f5b..4dcd096 100644
--- a/libgo/go/database/sql/fakedb_test.go
+++ b/libgo/go/database/sql/fakedb_test.go
@@ -58,9 +58,10 @@
 type fakeDB struct {
 	name string
 
-	mu      sync.Mutex
-	tables  map[string]*table
-	badConn bool
+	mu       sync.Mutex
+	tables   map[string]*table
+	badConn  bool
+	allowAny bool
 }
 
 type table struct {
@@ -83,11 +84,20 @@
 	cols []interface{} // must be same size as its table colname + coltype
 }
 
+type memToucher interface {
+	// touchMem reads & writes some memory, to help find data races.
+	touchMem()
+}
+
 type fakeConn struct {
 	db *fakeDB // where to return ourselves to
 
 	currTx *fakeTx
 
+	// Every operation writes to line to enable the race detector
+	// check for data races.
+	line int64
+
 	// Stats for tests:
 	mu          sync.Mutex
 	stmtsMade   int
@@ -99,6 +109,10 @@
 	stickyBad bool
 }
 
+func (c *fakeConn) touchMem() {
+	c.line++
+}
+
 func (c *fakeConn) incrStat(v *int) {
 	c.mu.Lock()
 	*v++
@@ -116,6 +130,7 @@
 }
 
 type fakeStmt struct {
+	memToucher
 	c *fakeConn
 	q string // just for debugging
 
@@ -298,6 +313,7 @@
 	if c.currTx != nil {
 		return nil, errors.New("already in a transaction")
 	}
+	c.touchMem()
 	c.currTx = &fakeTx{c: c}
 	return c.currTx, nil
 }
@@ -339,6 +355,7 @@
 			drv.mu.Unlock()
 		}
 	}()
+	c.touchMem()
 	if c.currTx != nil {
 		return errors.New("can't close fakeConn; in a Transaction")
 	}
@@ -352,12 +369,14 @@
 	return nil
 }
 
-func checkSubsetTypes(args []driver.NamedValue) error {
+func checkSubsetTypes(allowAny bool, args []driver.NamedValue) error {
 	for _, arg := range args {
 		switch arg.Value.(type) {
 		case int64, float64, bool, nil, []byte, string, time.Time:
 		default:
-			return fmt.Errorf("fakedb_test: invalid argument ordinal %[1]d: %[2]v, type %[2]T", arg.Ordinal, arg.Value)
+			if !allowAny {
+				return fmt.Errorf("fakedb_test: invalid argument ordinal %[1]d: %[2]v, type %[2]T", arg.Ordinal, arg.Value)
+			}
 		}
 	}
 	return nil
@@ -373,7 +392,7 @@
 	// just to check that all the args are of the proper types.
 	// ErrSkip is returned so the caller acts as if we didn't
 	// implement this at all.
-	err := checkSubsetTypes(args)
+	err := checkSubsetTypes(c.db.allowAny, args)
 	if err != nil {
 		return nil, err
 	}
@@ -390,7 +409,7 @@
 	// just to check that all the args are of the proper types.
 	// ErrSkip is returned so the caller acts as if we didn't
 	// implement this at all.
-	err := checkSubsetTypes(args)
+	err := checkSubsetTypes(c.db.allowAny, args)
 	if err != nil {
 		return nil, err
 	}
@@ -524,13 +543,14 @@
 		return nil, driver.ErrBadConn
 	}
 
+	c.touchMem()
 	var firstStmt, prev *fakeStmt
 	for _, query := range strings.Split(query, ";") {
 		parts := strings.Split(query, "|")
 		if len(parts) < 1 {
 			return nil, errf("empty query")
 		}
-		stmt := &fakeStmt{q: query, c: c}
+		stmt := &fakeStmt{q: query, c: c, memToucher: c}
 		if firstStmt == nil {
 			firstStmt = stmt
 		}
@@ -612,6 +632,7 @@
 	if s.c.db == nil {
 		panic("in fakeStmt.Close, conn's db is nil (already closed)")
 	}
+	s.touchMem()
 	if !s.closed {
 		s.c.incrStat(&s.c.stmtsClosed)
 		s.closed = true
@@ -642,10 +663,11 @@
 		return nil, driver.ErrBadConn
 	}
 
-	err := checkSubsetTypes(args)
+	err := checkSubsetTypes(s.c.db.allowAny, args)
 	if err != nil {
 		return nil, err
 	}
+	s.touchMem()
 
 	if s.wait > 0 {
 		time.Sleep(s.wait)
@@ -753,11 +775,12 @@
 		return nil, driver.ErrBadConn
 	}
 
-	err := checkSubsetTypes(args)
+	err := checkSubsetTypes(s.c.db.allowAny, args)
 	if err != nil {
 		return nil, err
 	}
 
+	s.touchMem()
 	db := s.c.db
 	if len(args) != s.placeholders {
 		panic("error in pkg db; should only get here if size is correct")
@@ -853,11 +876,12 @@
 	}
 
 	cursor := &rowsCursor{
-		posRow:  -1,
-		rows:    setMRows,
-		cols:    setColumns,
-		colType: setColType,
-		errPos:  -1,
+		parentMem: s.c,
+		posRow:    -1,
+		rows:      setMRows,
+		cols:      setColumns,
+		colType:   setColType,
+		errPos:    -1,
 	}
 	return cursor, nil
 }
@@ -877,6 +901,7 @@
 	if hookCommitBadConn != nil && hookCommitBadConn() {
 		return driver.ErrBadConn
 	}
+	tx.c.touchMem()
 	return nil
 }
 
@@ -888,16 +913,18 @@
 	if hookRollbackBadConn != nil && hookRollbackBadConn() {
 		return driver.ErrBadConn
 	}
+	tx.c.touchMem()
 	return nil
 }
 
 type rowsCursor struct {
-	cols    [][]string
-	colType [][]string
-	posSet  int
-	posRow  int
-	rows    [][]*row
-	closed  bool
+	parentMem memToucher
+	cols      [][]string
+	colType   [][]string
+	posSet    int
+	posRow    int
+	rows      [][]*row
+	closed    bool
 
 	// errPos and err are for making Next return early with error.
 	errPos int
@@ -907,6 +934,16 @@
 	// the original slice's first byte address.  we clone them
 	// just so we're able to corrupt them on close.
 	bytesClone map[*byte][]byte
+
+	// Every operation writes to line to enable the race detector
+	// check for data races.
+	// This is separate from the fakeConn.line to allow for drivers that
+	// can start multiple queries on the same transaction at the same time.
+	line int64
+}
+
+func (rc *rowsCursor) touchMem() {
+	rc.line++
 }
 
 func (rc *rowsCursor) Close() error {
@@ -915,6 +952,8 @@
 			bs[0] = 255 // first byte corrupted
 		}
 	}
+	rc.touchMem()
+	rc.parentMem.touchMem()
 	rc.closed = true
 	return nil
 }
@@ -937,6 +976,7 @@
 	if rc.closed {
 		return errors.New("fakedb: cursor is closed")
 	}
+	rc.touchMem()
 	rc.posRow++
 	if rc.posRow == rc.errPos {
 		return rc.err
@@ -970,10 +1010,12 @@
 }
 
 func (rc *rowsCursor) HasNextResultSet() bool {
+	rc.touchMem()
 	return rc.posSet < len(rc.rows)-1
 }
 
 func (rc *rowsCursor) NextResultSet() error {
+	rc.touchMem()
 	if rc.HasNextResultSet() {
 		rc.posSet++
 		rc.posRow = -1
@@ -1004,6 +1046,12 @@
 	return fmt.Sprintf("%v", v), nil
 }
 
+type anyTypeConverter struct{}
+
+func (anyTypeConverter) ConvertValue(v interface{}) (driver.Value, error) {
+	return v, nil
+}
+
 func converterForType(typ string) driver.ValueConverter {
 	switch typ {
 	case "bool":
@@ -1030,6 +1078,8 @@
 		return driver.Null{Converter: driver.DefaultParameterConverter}
 	case "datetime":
 		return driver.DefaultParameterConverter
+	case "any":
+		return anyTypeConverter{}
 	}
 	panic("invalid fakedb column type of " + typ)
 }
@@ -1056,6 +1106,8 @@
 		return reflect.TypeOf(NullFloat64{})
 	case "datetime":
 		return reflect.TypeOf(time.Time{})
+	case "any":
+		return reflect.TypeOf(new(interface{})).Elem()
 	}
 	panic("invalid fakedb column type of " + typ)
 }
diff --git a/libgo/go/database/sql/sql.go b/libgo/go/database/sql/sql.go
index f8a8844..c609fe4 100644
--- a/libgo/go/database/sql/sql.go
+++ b/libgo/go/database/sql/sql.go
@@ -278,6 +278,27 @@
 	Scan(src interface{}) error
 }
 
+// Out may be used to retrieve OUTPUT value parameters from stored procedures.
+//
+// Not all drivers and databases support OUTPUT value parameters.
+//
+// Example usage:
+//
+//   var outArg string
+//   _, err := db.ExecContext(ctx, "ProcName", sql.Named("Arg1", Out{Dest: &outArg}))
+type Out struct {
+	_Named_Fields_Required struct{}
+
+	// Dest is a pointer to the value that will be set to the result of the
+	// stored procedure's OUTPUT parameter.
+	Dest interface{}
+
+	// In is whether the parameter is an INOUT parameter. If so, the input value to the stored
+	// procedure is the dereferenced value of Dest's pointer, which is then replaced with
+	// the output value.
+	In bool
+}
+
 // ErrNoRows is returned by Scan when QueryRow doesn't return a
 // row. In such a case, QueryRow returns a placeholder *Row value that
 // defers this error until a Scan.
@@ -372,11 +393,19 @@
 	return dc.createdAt.Add(timeout).Before(nowFunc())
 }
 
-func (dc *driverConn) prepareLocked(ctx context.Context, query string) (*driverStmt, error) {
+// prepareLocked prepares the query on dc. When cg == nil the dc must keep track of
+// the prepared statements in a pool.
+func (dc *driverConn) prepareLocked(ctx context.Context, cg stmtConnGrabber, query string) (*driverStmt, error) {
 	si, err := ctxDriverPrepare(ctx, dc.ci, query)
 	if err != nil {
 		return nil, err
 	}
+	ds := &driverStmt{Locker: dc, si: si}
+
+	// No need to manage open statements if there is a single connection grabber.
+	if cg != nil {
+		return ds, nil
+	}
 
 	// Track each driverConn's open statements, so we can close them
 	// before closing the conn.
@@ -385,9 +414,7 @@
 	if dc.openStmt == nil {
 		dc.openStmt = make(map[*driverStmt]bool)
 	}
-	ds := &driverStmt{Locker: dc, si: si}
 	dc.openStmt[ds] = true
-
 	return ds, nil
 }
 
@@ -583,6 +610,17 @@
 	return db, nil
 }
 
+func (db *DB) pingDC(ctx context.Context, dc *driverConn, release func(error)) error {
+	var err error
+	if pinger, ok := dc.ci.(driver.Pinger); ok {
+		withLock(dc, func() {
+			err = pinger.Ping(ctx)
+		})
+	}
+	release(err)
+	return err
+}
+
 // PingContext verifies a connection to the database is still alive,
 // establishing a connection if necessary.
 func (db *DB) PingContext(ctx context.Context) error {
@@ -602,11 +640,7 @@
 		return err
 	}
 
-	if pinger, ok := dc.ci.(driver.Pinger); ok {
-		err = pinger.Ping(ctx)
-	}
-	db.putConn(dc, err)
-	return err
+	return db.pingDC(ctx, dc, dc.releaseConn)
 }
 
 // Ping verifies a connection to the database is still alive,
@@ -975,9 +1009,9 @@
 		db:        db,
 		createdAt: nowFunc(),
 		ci:        ci,
+		inUse:     true,
 	}
 	db.addDepLocked(dc, dc)
-	dc.inUse = true
 	db.mu.Unlock()
 	return dc, nil
 }
@@ -1137,22 +1171,39 @@
 	if err != nil {
 		return nil, err
 	}
+	return db.prepareDC(ctx, dc, dc.releaseConn, nil, query)
+}
+
+// prepareDC prepares a query on the driverConn and calls release before
+// returning. When cg == nil it implies that a connection pool is used, and
+// when cg != nil only a single driver connection is used.
+func (db *DB) prepareDC(ctx context.Context, dc *driverConn, release func(error), cg stmtConnGrabber, query string) (*Stmt, error) {
 	var ds *driverStmt
+	var err error
+	defer func() {
+		release(err)
+	}()
 	withLock(dc, func() {
-		ds, err = dc.prepareLocked(ctx, query)
+		ds, err = dc.prepareLocked(ctx, cg, query)
 	})
 	if err != nil {
-		db.putConn(dc, err)
 		return nil, err
 	}
 	stmt := &Stmt{
-		db:            db,
-		query:         query,
-		css:           []connStmt{{dc, ds}},
-		lastNumClosed: atomic.LoadUint64(&db.numClosed),
+		db:    db,
+		query: query,
+		cg:    cg,
+		cgds:  ds,
 	}
-	db.addDep(stmt, stmt)
-	db.putConn(dc, nil)
+
+	// When cg == nil this statement will need to keep track of various
+	// connections they are prepared on and record the stmt dependency on
+	// the DB.
+	if cg == nil {
+		stmt.css = []connStmt{{dc, ds}}
+		stmt.lastNumClosed = atomic.LoadUint64(&db.numClosed)
+		db.addDep(stmt, stmt)
+	}
 	return stmt, nil
 }
 
@@ -1179,18 +1230,21 @@
 	return db.ExecContext(context.Background(), query, args...)
 }
 
-func (db *DB) exec(ctx context.Context, query string, args []interface{}, strategy connReuseStrategy) (res Result, err error) {
+func (db *DB) exec(ctx context.Context, query string, args []interface{}, strategy connReuseStrategy) (Result, error) {
 	dc, err := db.conn(ctx, strategy)
 	if err != nil {
 		return nil, err
 	}
-	defer func() {
-		db.putConn(dc, err)
-	}()
+	return db.execDC(ctx, dc, dc.releaseConn, query, args)
+}
 
+func (db *DB) execDC(ctx context.Context, dc *driverConn, release func(error), query string, args []interface{}) (res Result, err error) {
+	defer func() {
+		release(err)
+	}()
 	if execer, ok := dc.ci.(driver.Execer); ok {
 		var dargs []driver.NamedValue
-		dargs, err = driverArgs(nil, args)
+		dargs, err = driverArgs(dc.ci, nil, args)
 		if err != nil {
 			return nil, err
 		}
@@ -1215,7 +1269,7 @@
 	}
 	ds := &driverStmt{Locker: dc, si: si}
 	defer ds.Close()
-	return resultFromStatement(ctx, ds, args...)
+	return resultFromStatement(ctx, dc.ci, ds, args...)
 }
 
 // QueryContext executes a query that returns rows, typically a SELECT.
@@ -1242,19 +1296,21 @@
 }
 
 func (db *DB) query(ctx context.Context, query string, args []interface{}, strategy connReuseStrategy) (*Rows, error) {
-	ci, err := db.conn(ctx, strategy)
+	dc, err := db.conn(ctx, strategy)
 	if err != nil {
 		return nil, err
 	}
 
-	return db.queryConn(ctx, ci, ci.releaseConn, query, args)
+	return db.queryDC(ctx, nil, dc, dc.releaseConn, query, args)
 }
 
-// queryConn executes a query on the given connection.
+// queryDC executes a query on the given connection.
 // The connection gets released by the releaseConn function.
-func (db *DB) queryConn(ctx context.Context, dc *driverConn, releaseConn func(error), query string, args []interface{}) (*Rows, error) {
+// The ctx context is from a query method and the txctx context is from an
+// optional transaction context.
+func (db *DB) queryDC(ctx, txctx context.Context, dc *driverConn, releaseConn func(error), query string, args []interface{}) (*Rows, error) {
 	if queryer, ok := dc.ci.(driver.Queryer); ok {
-		dargs, err := driverArgs(nil, args)
+		dargs, err := driverArgs(dc.ci, nil, args)
 		if err != nil {
 			releaseConn(err)
 			return nil, err
@@ -1275,7 +1331,7 @@
 				releaseConn: releaseConn,
 				rowsi:       rowsi,
 			}
-			rows.initContextClose(ctx)
+			rows.initContextClose(ctx, txctx)
 			return rows, nil
 		}
 	}
@@ -1291,7 +1347,7 @@
 	}
 
 	ds := &driverStmt{Locker: dc, si: si}
-	rowsi, err := rowsiFromStatement(ctx, ds, args...)
+	rowsi, err := rowsiFromStatement(ctx, dc.ci, ds, args...)
 	if err != nil {
 		ds.Close()
 		releaseConn(err)
@@ -1306,13 +1362,16 @@
 		rowsi:       rowsi,
 		closeStmt:   ds,
 	}
-	rows.initContextClose(ctx)
+	rows.initContextClose(ctx, txctx)
 	return rows, nil
 }
 
 // QueryRowContext executes a query that is expected to return at most one row.
 // QueryRowContext always returns a non-nil value. Errors are deferred until
 // Row's Scan method is called.
+// If the query selects no rows, the *Row's Scan will return ErrNoRows.
+// Otherwise, the *Row's Scan scans the first selected row and discards
+// the rest.
 func (db *DB) QueryRowContext(ctx context.Context, query string, args ...interface{}) *Row {
 	rows, err := db.QueryContext(ctx, query, args...)
 	return &Row{rows: rows, err: err}
@@ -1321,6 +1380,9 @@
 // QueryRow executes a query that is expected to return at most one row.
 // QueryRow always returns a non-nil value. Errors are deferred until
 // Row's Scan method is called.
+// If the query selects no rows, the *Row's Scan will return ErrNoRows.
+// Otherwise, the *Row's Scan scans the first selected row and discards
+// the rest.
 func (db *DB) QueryRow(query string, args ...interface{}) *Row {
 	return db.QueryRowContext(context.Background(), query, args...)
 }
@@ -1361,12 +1423,17 @@
 	if err != nil {
 		return nil, err
 	}
+	return db.beginDC(ctx, dc, dc.releaseConn, opts)
+}
+
+// beginDC starts a transaction. The provided dc must be valid and ready to use.
+func (db *DB) beginDC(ctx context.Context, dc *driverConn, release func(error), opts *TxOptions) (tx *Tx, err error) {
 	var txi driver.Tx
 	withLock(dc, func() {
 		txi, err = ctxDriverBegin(ctx, opts, dc.ci)
 	})
 	if err != nil {
-		db.putConn(dc, err)
+		release(err)
 		return nil, err
 	}
 
@@ -1374,11 +1441,12 @@
 	// The cancel function in Tx will be called after done is set to true.
 	ctx, cancel := context.WithCancel(ctx)
 	tx = &Tx{
-		db:     db,
-		dc:     dc,
-		txi:    txi,
-		cancel: cancel,
-		ctx:    ctx,
+		db:          db,
+		dc:          dc,
+		releaseConn: release,
+		txi:         txi,
+		cancel:      cancel,
+		ctx:         ctx,
 	}
 	go tx.awaitDone()
 	return tx, nil
@@ -1389,6 +1457,189 @@
 	return db.driver
 }
 
+// ErrConnDone is returned by any operation that is performed on a connection
+// that has already been committed or rolled back.
+var ErrConnDone = errors.New("database/sql: connection is already closed")
+
+// Conn returns a single connection by either opening a new connection
+// or returning an existing connection from the connection pool. Conn will
+// block until either a connection is returned or ctx is canceled.
+// Queries run on the same Conn will be run in the same database session.
+//
+// Every Conn must be returned to the database pool after use by
+// calling Conn.Close.
+func (db *DB) Conn(ctx context.Context) (*Conn, error) {
+	var dc *driverConn
+	var err error
+	for i := 0; i < maxBadConnRetries; i++ {
+		dc, err = db.conn(ctx, cachedOrNewConn)
+		if err != driver.ErrBadConn {
+			break
+		}
+	}
+	if err == driver.ErrBadConn {
+		dc, err = db.conn(ctx, cachedOrNewConn)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	conn := &Conn{
+		db: db,
+		dc: dc,
+	}
+	return conn, nil
+}
+
+type releaseConn func(error)
+
+// Conn represents a single database session rather a pool of database
+// sessions. Prefer running queries from DB unless there is a specific
+// need for a continuous single database session.
+//
+// A Conn must call Close to return the connection to the database pool
+// and may do so concurrently with a running query.
+//
+// After a call to Close, all operations on the
+// connection fail with ErrConnDone.
+type Conn struct {
+	db *DB
+
+	// closemu prevents the connection from closing while there
+	// is an active query. It is held for read during queries
+	// and exclusively during close.
+	closemu sync.RWMutex
+
+	// dc is owned until close, at which point
+	// it's returned to the connection pool.
+	dc *driverConn
+
+	// done transitions from 0 to 1 exactly once, on close.
+	// Once done, all operations fail with ErrConnDone.
+	// Use atomic operations on value when checking value.
+	done int32
+}
+
+func (c *Conn) grabConn(context.Context) (*driverConn, releaseConn, error) {
+	if atomic.LoadInt32(&c.done) != 0 {
+		return nil, nil, ErrConnDone
+	}
+	c.closemu.RLock()
+	return c.dc, c.closemuRUnlockCondReleaseConn, nil
+}
+
+// PingContext verifies the connection to the database is still alive.
+func (c *Conn) PingContext(ctx context.Context) error {
+	dc, release, err := c.grabConn(ctx)
+	if err != nil {
+		return err
+	}
+	return c.db.pingDC(ctx, dc, release)
+}
+
+// ExecContext executes a query without returning any rows.
+// The args are for any placeholder parameters in the query.
+func (c *Conn) ExecContext(ctx context.Context, query string, args ...interface{}) (Result, error) {
+	dc, release, err := c.grabConn(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return c.db.execDC(ctx, dc, release, query, args)
+}
+
+// QueryContext executes a query that returns rows, typically a SELECT.
+// The args are for any placeholder parameters in the query.
+func (c *Conn) QueryContext(ctx context.Context, query string, args ...interface{}) (*Rows, error) {
+	dc, release, err := c.grabConn(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return c.db.queryDC(ctx, nil, dc, release, query, args)
+}
+
+// QueryRowContext executes a query that is expected to return at most one row.
+// QueryRowContext always returns a non-nil value. Errors are deferred until
+// Row's Scan method is called.
+// If the query selects no rows, the *Row's Scan will return ErrNoRows.
+// Otherwise, the *Row's Scan scans the first selected row and discards
+// the rest.
+func (c *Conn) QueryRowContext(ctx context.Context, query string, args ...interface{}) *Row {
+	rows, err := c.QueryContext(ctx, query, args...)
+	return &Row{rows: rows, err: err}
+}
+
+// PrepareContext creates a prepared statement for later queries or executions.
+// Multiple queries or executions may be run concurrently from the
+// returned statement.
+// The caller must call the statement's Close method
+// when the statement is no longer needed.
+//
+// The provided context is used for the preparation of the statement, not for the
+// execution of the statement.
+func (c *Conn) PrepareContext(ctx context.Context, query string) (*Stmt, error) {
+	dc, release, err := c.grabConn(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return c.db.prepareDC(ctx, dc, release, c, query)
+}
+
+// BeginTx starts a transaction.
+//
+// The provided context is used until the transaction is committed or rolled back.
+// If the context is canceled, the sql package will roll back
+// the transaction. Tx.Commit will return an error if the context provided to
+// BeginTx is canceled.
+//
+// The provided TxOptions is optional and may be nil if defaults should be used.
+// If a non-default isolation level is used that the driver doesn't support,
+// an error will be returned.
+func (c *Conn) BeginTx(ctx context.Context, opts *TxOptions) (*Tx, error) {
+	dc, release, err := c.grabConn(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return c.db.beginDC(ctx, dc, release, opts)
+}
+
+// closemuRUnlockCondReleaseConn read unlocks closemu
+// as the sql operation is done with the dc.
+func (c *Conn) closemuRUnlockCondReleaseConn(err error) {
+	c.closemu.RUnlock()
+	if err == driver.ErrBadConn {
+		c.close(err)
+	}
+}
+
+func (c *Conn) txCtx() context.Context {
+	return nil
+}
+
+func (c *Conn) close(err error) error {
+	if !atomic.CompareAndSwapInt32(&c.done, 0, 1) {
+		return ErrConnDone
+	}
+
+	// Lock around releasing the driver connection
+	// to ensure all queries have been stopped before doing so.
+	c.closemu.Lock()
+	defer c.closemu.Unlock()
+
+	c.dc.releaseConn(err)
+	c.dc = nil
+	c.db = nil
+	return err
+}
+
+// Close returns the connection to the connection pool.
+// All operations after a Close will return with ErrConnDone.
+// Close is safe to call concurrently with other operations and will
+// block until all other operations finish. It may be useful to first
+// cancel any used context and then call close directly after.
+func (c *Conn) Close() error {
+	return c.close(nil)
+}
+
 // Tx is an in-progress database transaction.
 //
 // A transaction must end with a call to Commit or Rollback.
@@ -1412,6 +1663,10 @@
 	dc  *driverConn
 	txi driver.Tx
 
+	// releaseConn is called once the Tx is closed to release
+	// any held driverConn back to the pool.
+	releaseConn func(error)
+
 	// done transitions from 0 to 1 exactly once, on Commit
 	// or Rollback. once done, all operations fail with
 	// ErrTxDone.
@@ -1425,7 +1680,7 @@
 		v []*Stmt
 	}
 
-	// cancel is called after done transitions from false to true.
+	// cancel is called after done transitions from 0 to 1.
 	cancel func()
 
 	// ctx lives for the life of the transaction.
@@ -1457,11 +1712,12 @@
 // close returns the connection to the pool and
 // must only be called by Tx.rollback or Tx.Commit.
 func (tx *Tx) close(err error) {
+	tx.cancel()
+
 	tx.closemu.Lock()
 	defer tx.closemu.Unlock()
 
-	tx.db.putConn(tx.dc, err)
-	tx.cancel()
+	tx.releaseConn(err)
 	tx.dc = nil
 	tx.txi = nil
 }
@@ -1470,19 +1726,36 @@
 // a successful call to (*Tx).grabConn. For tests.
 var hookTxGrabConn func()
 
-func (tx *Tx) grabConn(ctx context.Context) (*driverConn, error) {
+func (tx *Tx) grabConn(ctx context.Context) (*driverConn, releaseConn, error) {
 	select {
 	default:
 	case <-ctx.Done():
-		return nil, ctx.Err()
+		return nil, nil, ctx.Err()
 	}
+
+	// closeme.RLock must come before the check for isDone to prevent the Tx from
+	// closing while a query is executing.
+	tx.closemu.RLock()
 	if tx.isDone() {
-		return nil, ErrTxDone
+		tx.closemu.RUnlock()
+		return nil, nil, ErrTxDone
 	}
 	if hookTxGrabConn != nil { // test hook
 		hookTxGrabConn()
 	}
-	return tx.dc, nil
+	return tx.dc, tx.closemuRUnlockRelease, nil
+}
+
+func (tx *Tx) txCtx() context.Context {
+	return tx.ctx
+}
+
+// closemuRUnlockRelease is used as a func(error) method value in
+// ExecContext and QueryContext. Unlocking in the releaseConn keeps
+// the driver conn from being returned to the connection pool until
+// the Rows has been closed.
+func (tx *Tx) closemuRUnlockRelease(error) {
+	tx.closemu.RUnlock()
 }
 
 // Closes all Stmts prepared for this transaction.
@@ -1540,7 +1813,7 @@
 	return tx.rollback(false)
 }
 
-// Prepare creates a prepared statement for use within a transaction.
+// PrepareContext creates a prepared statement for use within a transaction.
 //
 // The returned statement operates within the transaction and will be closed
 // when the transaction has been committed or rolled back.
@@ -1551,44 +1824,15 @@
 // for the execution of the returned statement. The returned statement
 // will run in the transaction context.
 func (tx *Tx) PrepareContext(ctx context.Context, query string) (*Stmt, error) {
-	tx.closemu.RLock()
-	defer tx.closemu.RUnlock()
-
-	// TODO(bradfitz): We could be more efficient here and either
-	// provide a method to take an existing Stmt (created on
-	// perhaps a different Conn), and re-create it on this Conn if
-	// necessary. Or, better: keep a map in DB of query string to
-	// Stmts, and have Stmt.Execute do the right thing and
-	// re-prepare if the Conn in use doesn't have that prepared
-	// statement. But we'll want to avoid caching the statement
-	// in the case where we only call conn.Prepare implicitly
-	// (such as in db.Exec or tx.Exec), but the caller package
-	// can't be holding a reference to the returned statement.
-	// Perhaps just looking at the reference count (by noting
-	// Stmt.Close) would be enough. We might also want a finalizer
-	// on Stmt to drop the reference count.
-	dc, err := tx.grabConn(ctx)
+	dc, release, err := tx.grabConn(ctx)
 	if err != nil {
 		return nil, err
 	}
 
-	var si driver.Stmt
-	withLock(dc, func() {
-		si, err = ctxDriverPrepare(ctx, dc.ci, query)
-	})
+	stmt, err := tx.db.prepareDC(ctx, dc, release, tx, query)
 	if err != nil {
 		return nil, err
 	}
-
-	stmt := &Stmt{
-		db: tx.db,
-		tx: tx,
-		txds: &driverStmt{
-			Locker: dc,
-			si:     si,
-		},
-		query: query,
-	}
 	tx.stmts.Lock()
 	tx.stmts.v = append(tx.stmts.v, stmt)
 	tx.stmts.Unlock()
@@ -1618,34 +1862,67 @@
 // The returned statement operates within the transaction and will be closed
 // when the transaction has been committed or rolled back.
 func (tx *Tx) StmtContext(ctx context.Context, stmt *Stmt) *Stmt {
-	tx.closemu.RLock()
-	defer tx.closemu.RUnlock()
-
-	// TODO(bradfitz): optimize this. Currently this re-prepares
-	// each time. This is fine for now to illustrate the API but
-	// we should really cache already-prepared statements
-	// per-Conn. See also the big comment in Tx.Prepare.
+	dc, release, err := tx.grabConn(ctx)
+	if err != nil {
+		return &Stmt{stickyErr: err}
+	}
+	defer release(nil)
 
 	if tx.db != stmt.db {
 		return &Stmt{stickyErr: errors.New("sql: Tx.Stmt: statement from different database used")}
 	}
-	dc, err := tx.grabConn(ctx)
-	if err != nil {
-		return &Stmt{stickyErr: err}
-	}
 	var si driver.Stmt
-	withLock(dc, func() {
-		si, err = ctxDriverPrepare(ctx, dc.ci, stmt.query)
-	})
+	var parentStmt *Stmt
+	stmt.mu.Lock()
+	if stmt.closed || stmt.cg != nil {
+		// If the statement has been closed or already belongs to a
+		// transaction, we can't reuse it in this connection.
+		// Since tx.StmtContext should never need to be called with a
+		// Stmt already belonging to tx, we ignore this edge case and
+		// re-prepare the statement in this case. No need to add
+		// code-complexity for this.
+		stmt.mu.Unlock()
+		withLock(dc, func() {
+			si, err = ctxDriverPrepare(ctx, dc.ci, stmt.query)
+		})
+		if err != nil {
+			return &Stmt{stickyErr: err}
+		}
+	} else {
+		stmt.removeClosedStmtLocked()
+		// See if the statement has already been prepared on this connection,
+		// and reuse it if possible.
+		for _, v := range stmt.css {
+			if v.dc == dc {
+				si = v.ds.si
+				break
+			}
+		}
+
+		stmt.mu.Unlock()
+
+		if si == nil {
+			cs, err := stmt.prepareOnConnLocked(ctx, dc)
+			if err != nil {
+				return &Stmt{stickyErr: err}
+			}
+			si = cs.si
+		}
+		parentStmt = stmt
+	}
+
 	txs := &Stmt{
 		db: tx.db,
-		tx: tx,
-		txds: &driverStmt{
+		cg: tx,
+		cgds: &driverStmt{
 			Locker: dc,
 			si:     si,
 		},
-		query:     stmt.query,
-		stickyErr: err,
+		parentStmt: parentStmt,
+		query:      stmt.query,
+	}
+	if parentStmt != nil {
+		tx.db.addDep(parentStmt, txs)
 	}
 	tx.stmts.Lock()
 	tx.stmts.v = append(tx.stmts.v, txs)
@@ -1672,42 +1949,11 @@
 // ExecContext executes a query that doesn't return rows.
 // For example: an INSERT and UPDATE.
 func (tx *Tx) ExecContext(ctx context.Context, query string, args ...interface{}) (Result, error) {
-	tx.closemu.RLock()
-	defer tx.closemu.RUnlock()
-
-	dc, err := tx.grabConn(ctx)
+	dc, release, err := tx.grabConn(ctx)
 	if err != nil {
 		return nil, err
 	}
-
-	if execer, ok := dc.ci.(driver.Execer); ok {
-		dargs, err := driverArgs(nil, args)
-		if err != nil {
-			return nil, err
-		}
-		var resi driver.Result
-		withLock(dc, func() {
-			resi, err = ctxDriverExec(ctx, execer, query, dargs)
-		})
-		if err == nil {
-			return driverResult{dc, resi}, nil
-		}
-		if err != driver.ErrSkip {
-			return nil, err
-		}
-	}
-
-	var si driver.Stmt
-	withLock(dc, func() {
-		si, err = ctxDriverPrepare(ctx, dc.ci, query)
-	})
-	if err != nil {
-		return nil, err
-	}
-	ds := &driverStmt{Locker: dc, si: si}
-	defer ds.Close()
-
-	return resultFromStatement(ctx, ds, args...)
+	return tx.db.execDC(ctx, dc, release, query, args)
 }
 
 // Exec executes a query that doesn't return rows.
@@ -1718,15 +1964,12 @@
 
 // QueryContext executes a query that returns rows, typically a SELECT.
 func (tx *Tx) QueryContext(ctx context.Context, query string, args ...interface{}) (*Rows, error) {
-	tx.closemu.RLock()
-	defer tx.closemu.RUnlock()
-
-	dc, err := tx.grabConn(ctx)
+	dc, release, err := tx.grabConn(ctx)
 	if err != nil {
 		return nil, err
 	}
-	releaseConn := func(error) {}
-	return tx.db.queryConn(ctx, dc, releaseConn, query, args)
+
+	return tx.db.queryDC(ctx, tx.ctx, dc, release, query, args)
 }
 
 // Query executes a query that returns rows, typically a SELECT.
@@ -1737,6 +1980,9 @@
 // QueryRowContext executes a query that is expected to return at most one row.
 // QueryRowContext always returns a non-nil value. Errors are deferred until
 // Row's Scan method is called.
+// If the query selects no rows, the *Row's Scan will return ErrNoRows.
+// Otherwise, the *Row's Scan scans the first selected row and discards
+// the rest.
 func (tx *Tx) QueryRowContext(ctx context.Context, query string, args ...interface{}) *Row {
 	rows, err := tx.QueryContext(ctx, query, args...)
 	return &Row{rows: rows, err: err}
@@ -1745,6 +1991,9 @@
 // QueryRow executes a query that is expected to return at most one row.
 // QueryRow always returns a non-nil value. Errors are deferred until
 // Row's Scan method is called.
+// If the query selects no rows, the *Row's Scan will return ErrNoRows.
+// Otherwise, the *Row's Scan scans the first selected row and discards
+// the rest.
 func (tx *Tx) QueryRow(query string, args ...interface{}) *Row {
 	return tx.QueryRowContext(context.Background(), query, args...)
 }
@@ -1755,6 +2004,24 @@
 	ds *driverStmt
 }
 
+// stmtConnGrabber represents a Tx or Conn that will return the underlying
+// driverConn and release function.
+type stmtConnGrabber interface {
+	// grabConn returns the driverConn and the associated release function
+	// that must be called when the operation completes.
+	grabConn(context.Context) (*driverConn, releaseConn, error)
+
+	// txCtx returns the transaction context if available.
+	// The returned context should be selected on along with
+	// any query context when awaiting a cancel.
+	txCtx() context.Context
+}
+
+var (
+	_ stmtConnGrabber = &Tx{}
+	_ stmtConnGrabber = &Conn{}
+)
+
 // Stmt is a prepared statement.
 // A Stmt is safe for concurrent use by multiple goroutines.
 type Stmt struct {
@@ -1765,17 +2032,29 @@
 
 	closemu sync.RWMutex // held exclusively during close, for read otherwise.
 
-	// If in a transaction, else both nil:
-	tx   *Tx
-	txds *driverStmt
+	// If Stmt is prepared on a Tx or Conn then cg is present and will
+	// only ever grab a connection from cg.
+	// If cg is nil then the Stmt must grab an arbitrary connection
+	// from db and determine if it must prepare the stmt again by
+	// inspecting css.
+	cg   stmtConnGrabber
+	cgds *driverStmt
+
+	// parentStmt is set when a transaction-specific statement
+	// is requested from an identical statement prepared on the same
+	// conn. parentStmt is used to track the dependency of this statement
+	// on its originating ("parent") statement so that parentStmt may
+	// be closed by the user without them having to know whether or not
+	// any transactions are still using it.
+	parentStmt *Stmt
 
 	mu     sync.Mutex // protects the rest of the fields
 	closed bool
 
 	// css is a list of underlying driver statement interfaces
 	// that are valid on particular connections. This is only
-	// used if tx == nil and one is found that has idle
-	// connections. If tx != nil, txsi is always used.
+	// used if cg == nil and one is found that has idle
+	// connections. If cg != nil, cgds is always used.
 	css []connStmt
 
 	// lastNumClosed is copied from db.numClosed when Stmt is created
@@ -1790,8 +2069,12 @@
 	defer s.closemu.RUnlock()
 
 	var res Result
-	for i := 0; i < maxBadConnRetries; i++ {
-		_, releaseConn, ds, err := s.connStmt(ctx)
+	strategy := cachedOrNewConn
+	for i := 0; i < maxBadConnRetries+1; i++ {
+		if i == maxBadConnRetries {
+			strategy = alwaysNewConn
+		}
+		dc, releaseConn, ds, err := s.connStmt(ctx, strategy)
 		if err != nil {
 			if err == driver.ErrBadConn {
 				continue
@@ -1799,7 +2082,7 @@
 			return nil, err
 		}
 
-		res, err = resultFromStatement(ctx, ds, args...)
+		res, err = resultFromStatement(ctx, dc.ci, ds, args...)
 		releaseConn(err)
 		if err != driver.ErrBadConn {
 			return res, err
@@ -1814,23 +2097,8 @@
 	return s.ExecContext(context.Background(), args...)
 }
 
-func driverNumInput(ds *driverStmt) int {
-	ds.Lock()
-	defer ds.Unlock() // in case NumInput panics
-	return ds.si.NumInput()
-}
-
-func resultFromStatement(ctx context.Context, ds *driverStmt, args ...interface{}) (Result, error) {
-	want := driverNumInput(ds)
-
-	// -1 means the driver doesn't know how to count the number of
-	// placeholders, so we won't sanity check input here and instead let the
-	// driver deal with errors.
-	if want != -1 && len(args) != want {
-		return nil, fmt.Errorf("sql: expected %d arguments, got %d", want, len(args))
-	}
-
-	dargs, err := driverArgs(ds, args)
+func resultFromStatement(ctx context.Context, ci driver.Conn, ds *driverStmt, args ...interface{}) (Result, error) {
+	dargs, err := driverArgs(ci, ds, args)
 	if err != nil {
 		return nil, err
 	}
@@ -1874,7 +2142,7 @@
 // connStmt returns a free driver connection on which to execute the
 // statement, a function to call to release the connection, and a
 // statement bound to that connection.
-func (s *Stmt) connStmt(ctx context.Context) (ci *driverConn, releaseConn func(error), ds *driverStmt, err error) {
+func (s *Stmt) connStmt(ctx context.Context, strategy connReuseStrategy) (dc *driverConn, releaseConn func(error), ds *driverStmt, err error) {
 	if err = s.stickyErr; err != nil {
 		return
 	}
@@ -1885,22 +2153,21 @@
 		return
 	}
 
-	// In a transaction, we always use the connection that the
-	// transaction was created on.
-	if s.tx != nil {
+	// In a transaction or connection, we always use the connection that the
+	// the stmt was created on.
+	if s.cg != nil {
 		s.mu.Unlock()
-		ci, err = s.tx.grabConn(ctx) // blocks, waiting for the connection.
+		dc, releaseConn, err = s.cg.grabConn(ctx) // blocks, waiting for the connection.
 		if err != nil {
 			return
 		}
-		releaseConn = func(error) {}
-		return ci, releaseConn, s.txds, nil
+		return dc, releaseConn, s.cgds, nil
 	}
 
 	s.removeClosedStmtLocked()
 	s.mu.Unlock()
 
-	dc, err := s.db.conn(ctx, cachedOrNewConn)
+	dc, err = s.db.conn(ctx, strategy)
 	if err != nil {
 		return nil, nil, nil, err
 	}
@@ -1916,20 +2183,30 @@
 
 	// No luck; we need to prepare the statement on this connection
 	withLock(dc, func() {
-		ds, err = dc.prepareLocked(ctx, s.query)
+		ds, err = s.prepareOnConnLocked(ctx, dc)
 	})
 	if err != nil {
-		s.db.putConn(dc, err)
+		dc.releaseConn(err)
 		return nil, nil, nil, err
 	}
-	s.mu.Lock()
-	cs := connStmt{dc, ds}
-	s.css = append(s.css, cs)
-	s.mu.Unlock()
 
 	return dc, dc.releaseConn, ds, nil
 }
 
+// prepareOnConnLocked prepares the query in Stmt s on dc and adds it to the list of
+// open connStmt on the statement. It assumes the caller is holding the lock on dc.
+func (s *Stmt) prepareOnConnLocked(ctx context.Context, dc *driverConn) (*driverStmt, error) {
+	si, err := dc.prepareLocked(ctx, s.cg, s.query)
+	if err != nil {
+		return nil, err
+	}
+	cs := connStmt{dc, si}
+	s.mu.Lock()
+	s.css = append(s.css, cs)
+	s.mu.Unlock()
+	return cs.ds, nil
+}
+
 // QueryContext executes a prepared query statement with the given arguments
 // and returns the query results as a *Rows.
 func (s *Stmt) QueryContext(ctx context.Context, args ...interface{}) (*Rows, error) {
@@ -1937,8 +2214,12 @@
 	defer s.closemu.RUnlock()
 
 	var rowsi driver.Rows
-	for i := 0; i < maxBadConnRetries; i++ {
-		dc, releaseConn, ds, err := s.connStmt(ctx)
+	strategy := cachedOrNewConn
+	for i := 0; i < maxBadConnRetries+1; i++ {
+		if i == maxBadConnRetries {
+			strategy = alwaysNewConn
+		}
+		dc, releaseConn, ds, err := s.connStmt(ctx, strategy)
 		if err != nil {
 			if err == driver.ErrBadConn {
 				continue
@@ -1946,7 +2227,7 @@
 			return nil, err
 		}
 
-		rowsi, err = rowsiFromStatement(ctx, ds, args...)
+		rowsi, err = rowsiFromStatement(ctx, dc.ci, ds, args...)
 		if err == nil {
 			// Note: ownership of ci passes to the *Rows, to be freed
 			// with releaseConn.
@@ -1955,12 +2236,21 @@
 				rowsi: rowsi,
 				// releaseConn set below
 			}
+			// addDep must be added before initContextClose or it could attempt
+			// to removeDep before it has been added.
 			s.db.addDep(s, rows)
+
+			// releaseConn must be set before initContextClose or it could
+			// release the connection before it is set.
 			rows.releaseConn = func(err error) {
 				releaseConn(err)
 				s.db.removeDep(s, rows)
 			}
-			rows.initContextClose(ctx)
+			var txctx context.Context
+			if s.cg != nil {
+				txctx = s.cg.txCtx()
+			}
+			rows.initContextClose(ctx, txctx)
 			return rows, nil
 		}
 
@@ -1978,7 +2268,7 @@
 	return s.QueryContext(context.Background(), args...)
 }
 
-func rowsiFromStatement(ctx context.Context, ds *driverStmt, args ...interface{}) (driver.Rows, error) {
+func rowsiFromStatement(ctx context.Context, ci driver.Conn, ds *driverStmt, args ...interface{}) (driver.Rows, error) {
 	var want int
 	withLock(ds, func() {
 		want = ds.si.NumInput()
@@ -1991,7 +2281,7 @@
 		return nil, fmt.Errorf("sql: statement expects %d inputs; got %d", want, len(args))
 	}
 
-	dargs, err := driverArgs(ds, args)
+	dargs, err := driverArgs(ci, ds, args)
 	if err != nil {
 		return nil, err
 	}
@@ -2054,13 +2344,21 @@
 		return nil
 	}
 	s.closed = true
+	txds := s.cgds
+	s.cgds = nil
+
 	s.mu.Unlock()
 
-	if s.tx != nil {
-		return s.txds.Close()
+	if s.cg == nil {
+		return s.db.removeDep(s, s)
 	}
 
-	return s.db.removeDep(s, s)
+	if s.parentStmt != nil {
+		// If parentStmt is set, we must not close s.txds since it's stored
+		// in the css array of the parentStmt.
+		return s.db.removeDep(s.parentStmt, s)
+	}
+	return txds.Close()
 }
 
 func (s *Stmt) finalClose() error {
@@ -2107,18 +2405,28 @@
 	lasterr error // non-nil only if closed is true
 
 	// lastcols is only used in Scan, Next, and NextResultSet which are expected
-	// not not be called concurrently.
+	// not to be called concurrently.
 	lastcols []driver.Value
 }
 
-func (rs *Rows) initContextClose(ctx context.Context) {
+func (rs *Rows) initContextClose(ctx, txctx context.Context) {
 	ctx, rs.cancel = context.WithCancel(ctx)
-	go rs.awaitDone(ctx)
+	go rs.awaitDone(ctx, txctx)
 }
 
-// awaitDone blocks until the rows are closed or the context canceled.
-func (rs *Rows) awaitDone(ctx context.Context) {
-	<-ctx.Done()
+// awaitDone blocks until either ctx or txctx is canceled. The ctx is provided
+// from the query context and is canceled when the query Rows is closed.
+// If the query was issued in a transaction, the transaction's context
+// is also provided in txctx to ensure Rows is closed if the Tx is closed.
+func (rs *Rows) awaitDone(ctx, txctx context.Context) {
+	var txctxDone <-chan struct{}
+	if txctx != nil {
+		txctxDone = txctx.Done()
+	}
+	select {
+	case <-ctx.Done():
+	case <-txctxDone:
+	}
 	rs.close(ctx.Err())
 }
 
@@ -2407,7 +2715,7 @@
 }
 
 // rowsCloseHook returns a function so tests may install the
-// hook throug a test only mutex.
+// hook through a test only mutex.
 var rowsCloseHook = func() func(*Rows, *error) { return nil }
 
 // Close closes the Rows, preventing further enumeration. If Next is called
@@ -2431,7 +2739,9 @@
 		rs.lasterr = err
 	}
 
-	err = rs.rowsi.Close()
+	withLock(rs.dc, func() {
+		err = rs.rowsi.Close()
+	})
 	if fn := rowsCloseHook(); fn != nil {
 		fn(rs, &err)
 	}
diff --git a/libgo/go/database/sql/sql_test.go b/libgo/go/database/sql/sql_test.go
index 381aafc..c935eb4 100644
--- a/libgo/go/database/sql/sql_test.go
+++ b/libgo/go/database/sql/sql_test.go
@@ -139,6 +139,7 @@
 			t.Errorf("Error closing fakeConn: %v", err)
 		}
 	})
+	db.mu.Lock()
 	for i, dc := range db.freeConn {
 		if n := len(dc.openStmt); n > 0 {
 			// Just a sanity check. This is legal in
@@ -149,6 +150,8 @@
 			t.Errorf("while closing db, freeConn %d/%d had %d open stmts; want 0", i, len(db.freeConn), n)
 		}
 	}
+	db.mu.Unlock()
+
 	err := db.Close()
 	if err != nil {
 		t.Fatalf("error closing DB: %v", err)
@@ -322,7 +325,7 @@
 	select {
 	case <-ctx.Done():
 		if err := ctx.Err(); err != context.Canceled {
-			t.Fatalf("context err = %v; want context.Canceled", ctx.Err())
+			t.Fatalf("context err = %v; want context.Canceled", err)
 		}
 	default:
 		t.Fatalf("context err = nil; want context.Canceled")
@@ -413,7 +416,7 @@
 	db := newTestDB(t, "people")
 	defer closeDB(t, db)
 
-	ctx, cancel := context.WithTimeout(context.Background(), time.Millisecond*15)
+	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Millisecond)
 	defer cancel()
 
 	tx, err := db.BeginTx(ctx, nil)
@@ -590,13 +593,13 @@
 	saturate.Wait()
 
 	// Now cancel the request while it is waiting.
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second*2)
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
 	defer cancel()
 
 	for i := 0; i < max; i++ {
 		ctxReq, cancelReq := context.WithCancel(ctx)
 		go func() {
-			time.Sleep(time.Millisecond * 100)
+			time.Sleep(100 * time.Millisecond)
 			cancelReq()
 		}()
 		err := db.PingContext(ctxReq)
@@ -874,7 +877,7 @@
 		msg  string
 	}{
 		{&Stmt{stickyErr: want}, "stickyErr not propagated"},
-		{&Stmt{tx: &Tx{}, txds: &driverStmt{Locker: &sync.Mutex{}, si: stubDriverStmt{want}}}, "driverStmt.Close() error not propagated"},
+		{&Stmt{cg: &Tx{}, cgds: &driverStmt{Locker: &sync.Mutex{}, si: stubDriverStmt{want}}}, "driverStmt.Close() error not propagated"},
 	}
 	for _, test := range tests {
 		if err := test.stmt.Close(); err != want {
@@ -1024,6 +1027,196 @@
 	}
 }
 
+func TestTxStmtPreparedOnce(t *testing.T) {
+	db := newTestDB(t, "")
+	defer closeDB(t, db)
+	exec(t, db, "CREATE|t1|name=string,age=int32")
+
+	prepares0 := numPrepares(t, db)
+
+	// db.Prepare increments numPrepares.
+	stmt, err := db.Prepare("INSERT|t1|name=?,age=?")
+	if err != nil {
+		t.Fatalf("Stmt, err = %v, %v", stmt, err)
+	}
+	defer stmt.Close()
+
+	tx, err := db.Begin()
+	if err != nil {
+		t.Fatalf("Begin = %v", err)
+	}
+
+	txs1 := tx.Stmt(stmt)
+	txs2 := tx.Stmt(stmt)
+
+	_, err = txs1.Exec("Go", 7)
+	if err != nil {
+		t.Fatalf("Exec = %v", err)
+	}
+	txs1.Close()
+
+	_, err = txs2.Exec("Gopher", 8)
+	if err != nil {
+		t.Fatalf("Exec = %v", err)
+	}
+	txs2.Close()
+
+	err = tx.Commit()
+	if err != nil {
+		t.Fatalf("Commit = %v", err)
+	}
+
+	if prepares := numPrepares(t, db) - prepares0; prepares != 1 {
+		t.Errorf("executed %d Prepare statements; want 1", prepares)
+	}
+}
+
+func TestTxStmtClosedRePrepares(t *testing.T) {
+	db := newTestDB(t, "")
+	defer closeDB(t, db)
+	exec(t, db, "CREATE|t1|name=string,age=int32")
+
+	prepares0 := numPrepares(t, db)
+
+	// db.Prepare increments numPrepares.
+	stmt, err := db.Prepare("INSERT|t1|name=?,age=?")
+	if err != nil {
+		t.Fatalf("Stmt, err = %v, %v", stmt, err)
+	}
+	tx, err := db.Begin()
+	if err != nil {
+		t.Fatalf("Begin = %v", err)
+	}
+	err = stmt.Close()
+	if err != nil {
+		t.Fatalf("stmt.Close() = %v", err)
+	}
+	// tx.Stmt increments numPrepares because stmt is closed.
+	txs := tx.Stmt(stmt)
+	if txs.stickyErr != nil {
+		t.Fatal(txs.stickyErr)
+	}
+	if txs.parentStmt != nil {
+		t.Fatal("expected nil parentStmt")
+	}
+	_, err = txs.Exec(`Eric`, 82)
+	if err != nil {
+		t.Fatalf("txs.Exec = %v", err)
+	}
+
+	err = txs.Close()
+	if err != nil {
+		t.Fatalf("txs.Close = %v", err)
+	}
+
+	tx.Rollback()
+
+	if prepares := numPrepares(t, db) - prepares0; prepares != 2 {
+		t.Errorf("executed %d Prepare statements; want 2", prepares)
+	}
+}
+
+func TestParentStmtOutlivesTxStmt(t *testing.T) {
+	db := newTestDB(t, "")
+	defer closeDB(t, db)
+	exec(t, db, "CREATE|t1|name=string,age=int32")
+
+	// Make sure everything happens on the same connection.
+	db.SetMaxOpenConns(1)
+
+	prepares0 := numPrepares(t, db)
+
+	// db.Prepare increments numPrepares.
+	stmt, err := db.Prepare("INSERT|t1|name=?,age=?")
+	if err != nil {
+		t.Fatalf("Stmt, err = %v, %v", stmt, err)
+	}
+	defer stmt.Close()
+	tx, err := db.Begin()
+	if err != nil {
+		t.Fatalf("Begin = %v", err)
+	}
+	txs := tx.Stmt(stmt)
+	if len(stmt.css) != 1 {
+		t.Fatalf("len(stmt.css) = %v; want 1", len(stmt.css))
+	}
+	err = txs.Close()
+	if err != nil {
+		t.Fatalf("txs.Close() = %v", err)
+	}
+	err = tx.Rollback()
+	if err != nil {
+		t.Fatalf("tx.Rollback() = %v", err)
+	}
+	// txs must not be valid.
+	_, err = txs.Exec("Suzan", 30)
+	if err == nil {
+		t.Fatalf("txs.Exec(), expected err")
+	}
+	// Stmt must still be valid.
+	_, err = stmt.Exec("Janina", 25)
+	if err != nil {
+		t.Fatalf("stmt.Exec() = %v", err)
+	}
+
+	if prepares := numPrepares(t, db) - prepares0; prepares != 1 {
+		t.Errorf("executed %d Prepare statements; want 1", prepares)
+	}
+}
+
+// Test that tx.Stmt called with a statement already
+// associated with tx as argument re-prepares the same
+// statement again.
+func TestTxStmtFromTxStmtRePrepares(t *testing.T) {
+	db := newTestDB(t, "")
+	defer closeDB(t, db)
+	exec(t, db, "CREATE|t1|name=string,age=int32")
+	prepares0 := numPrepares(t, db)
+	// db.Prepare increments numPrepares.
+	stmt, err := db.Prepare("INSERT|t1|name=?,age=?")
+	if err != nil {
+		t.Fatalf("Stmt, err = %v, %v", stmt, err)
+	}
+	defer stmt.Close()
+
+	tx, err := db.Begin()
+	if err != nil {
+		t.Fatalf("Begin = %v", err)
+	}
+	txs1 := tx.Stmt(stmt)
+
+	// tx.Stmt(txs1) increments numPrepares because txs1 already
+	// belongs to a transaction (albeit the same transaction).
+	txs2 := tx.Stmt(txs1)
+	if txs2.stickyErr != nil {
+		t.Fatal(txs2.stickyErr)
+	}
+	if txs2.parentStmt != nil {
+		t.Fatal("expected nil parentStmt")
+	}
+	_, err = txs2.Exec(`Eric`, 82)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = txs1.Close()
+	if err != nil {
+		t.Fatalf("txs1.Close = %v", err)
+	}
+	err = txs2.Close()
+	if err != nil {
+		t.Fatalf("txs1.Close = %v", err)
+	}
+	err = tx.Rollback()
+	if err != nil {
+		t.Fatalf("tx.Rollback = %v", err)
+	}
+
+	if prepares := numPrepares(t, db) - prepares0; prepares != 2 {
+		t.Errorf("executed %d Prepare statements; want 2", prepares)
+	}
+}
+
 // Issue: https://golang.org/issue/2784
 // This test didn't fail before because we got lucky with the fakedb driver.
 // It was failing, and now not, in github.com/bradfitz/go-sql-test
@@ -1108,6 +1301,69 @@
 	}
 }
 
+func TestConnQuery(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	conn, err := db.Conn(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+
+	var name string
+	err = conn.QueryRowContext(ctx, "SELECT|people|name|age=?", 3).Scan(&name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if name != "Chris" {
+		t.Fatalf("unexpected result, got %q want Chris", name)
+	}
+
+	err = conn.PingContext(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestConnTx(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	conn, err := db.Conn(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+
+	tx, err := conn.BeginTx(ctx, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	insertName, insertAge := "Nancy", 33
+	_, err = tx.ExecContext(ctx, "INSERT|people|name=?,age=?,photo=APHOTO", insertName, insertAge)
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = tx.Commit()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var selectName string
+	err = conn.QueryRowContext(ctx, "SELECT|people|name|age=?", insertAge).Scan(&selectName)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if selectName != insertName {
+		t.Fatalf("got %q want %q", selectName, insertName)
+	}
+}
+
 // Tests fix for issue 2542, that we release a lock when querying on
 // a closed connection.
 func TestIssue2542Deadlock(t *testing.T) {
@@ -1831,8 +2087,8 @@
 	}
 
 	// Expire first conn
-	offset = time.Second * 11
-	db.SetConnMaxLifetime(time.Second * 10)
+	offset = 11 * time.Second
+	db.SetConnMaxLifetime(10 * time.Second)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -2078,9 +2334,13 @@
 // Test cases where there's more than maxBadConnRetries bad connections in the
 // pool (issue 8834)
 func TestManyErrBadConn(t *testing.T) {
-	manyErrBadConnSetup := func() *DB {
+	manyErrBadConnSetup := func(first ...func(db *DB)) *DB {
 		db := newTestDB(t, "people")
 
+		for _, f := range first {
+			f(db)
+		}
+
 		nconn := maxBadConnRetries + 1
 		db.SetMaxIdleConns(nconn)
 		db.SetMaxOpenConns(nconn)
@@ -2148,6 +2408,128 @@
 	if err = stmt.Close(); err != nil {
 		t.Fatal(err)
 	}
+
+	// Stmt.Exec
+	db = manyErrBadConnSetup(func(db *DB) {
+		stmt, err = db.Prepare("INSERT|people|name=Julia,age=19")
+		if err != nil {
+			t.Fatal(err)
+		}
+	})
+	defer closeDB(t, db)
+	_, err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err = stmt.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Stmt.Query
+	db = manyErrBadConnSetup(func(db *DB) {
+		stmt, err = db.Prepare("SELECT|people|age,name|")
+		if err != nil {
+			t.Fatal(err)
+		}
+	})
+	defer closeDB(t, db)
+	rows, err = stmt.Query()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err = rows.Close(); err != nil {
+		t.Fatal(err)
+	}
+	if err = stmt.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Conn
+	db = manyErrBadConnSetup()
+	defer closeDB(t, db)
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	conn, err := db.Conn(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = conn.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Ping
+	db = manyErrBadConnSetup()
+	defer closeDB(t, db)
+	err = db.PingContext(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+// TestIssue20575 ensures the Rows from query does not block
+// closing a transaction. Ensure Rows is closed while closing a trasaction.
+func TestIssue20575(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	tx, err := db.Begin()
+	if err != nil {
+		t.Fatal(err)
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	defer cancel()
+	_, err = tx.QueryContext(ctx, "SELECT|people|age,name|")
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Do not close Rows from QueryContext.
+	err = tx.Rollback()
+	if err != nil {
+		t.Fatal(err)
+	}
+	select {
+	default:
+	case <-ctx.Done():
+		t.Fatal("timeout: failed to rollback query without closing rows:", ctx.Err())
+	}
+}
+
+// TestIssue20622 tests closing the transaction before rows is closed, requires
+// the race detector to fail.
+func TestIssue20622(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	tx, err := db.BeginTx(ctx, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	rows, err := tx.Query("SELECT|people|age,name|")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	count := 0
+	for rows.Next() {
+		count++
+		var age int
+		var name string
+		if err := rows.Scan(&age, &name); err != nil {
+			t.Fatal("scan failed", err)
+		}
+
+		if count == 1 {
+			cancel()
+		}
+		time.Sleep(100 * time.Millisecond)
+	}
+	rows.Close()
+	tx.Commit()
 }
 
 // golang.org/issue/5718
@@ -2751,7 +3133,7 @@
 			if err != nil {
 				return
 			}
-			// This is expected to give a cancel error many, but not all the time.
+			// This is expected to give a cancel error most, but not all the time.
 			// Test failure will happen with a panic or other race condition being
 			// reported.
 			rows, _ := tx.QueryContext(ctx, "WAIT|"+qwait+"|SELECT|people|name|")
@@ -2766,6 +3148,46 @@
 	wg.Wait()
 }
 
+// TestIssue20160 attempts to test a short context life on a stmt Query.
+func TestIssue20160(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	ctx := context.Background()
+	sem := make(chan bool, 20)
+	var wg sync.WaitGroup
+
+	const milliWait = 30
+
+	stmt, err := db.PrepareContext(ctx, "SELECT|people|name|")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer stmt.Close()
+
+	for i := 0; i < 100; i++ {
+		sem <- true
+		wg.Add(1)
+		go func() {
+			defer func() {
+				<-sem
+				wg.Done()
+			}()
+			ctx, cancel := context.WithTimeout(ctx, time.Duration(rand.Intn(milliWait))*time.Millisecond)
+			defer cancel()
+
+			// This is expected to give a cancel error most, but not all the time.
+			// Test failure will happen with a panic or other race condition being
+			// reported.
+			rows, _ := stmt.QueryContext(ctx)
+			if rows != nil {
+				rows.Close()
+			}
+		}()
+	}
+	wg.Wait()
+}
+
 // TestIssue18719 closes the context right before use. The sql.driverConn
 // will nil out the ci on close in a lock, but if another process uses it right after
 // it will panic with on the nil ref.
@@ -2788,7 +3210,7 @@
 
 		// Wait for the context to cancel and tx to rollback.
 		for tx.isDone() == false {
-			time.Sleep(time.Millisecond * 3)
+			time.Sleep(3 * time.Millisecond)
 		}
 	}
 	defer func() { hookTxGrabConn = nil }()
@@ -2807,19 +3229,64 @@
 	// canceled context.
 
 	cancel()
-	waitForRowsClose(t, rows, 5*time.Second)
+}
+
+func TestIssue20647(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	conn, err := db.Conn(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+
+	stmt, err := conn.PrepareContext(ctx, "SELECT|people|name|")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer stmt.Close()
+
+	rows1, err := stmt.QueryContext(ctx)
+	if err != nil {
+		t.Fatal("rows1", err)
+	}
+	defer rows1.Close()
+
+	rows2, err := stmt.QueryContext(ctx)
+	if err != nil {
+		t.Fatal("rows2", err)
+	}
+	defer rows2.Close()
+
+	if rows1.dc != rows2.dc {
+		t.Fatal("stmt prepared on Conn does not use same connection")
+	}
 }
 
 func TestConcurrency(t *testing.T) {
-	doConcurrentTest(t, new(concurrentDBQueryTest))
-	doConcurrentTest(t, new(concurrentDBExecTest))
-	doConcurrentTest(t, new(concurrentStmtQueryTest))
-	doConcurrentTest(t, new(concurrentStmtExecTest))
-	doConcurrentTest(t, new(concurrentTxQueryTest))
-	doConcurrentTest(t, new(concurrentTxExecTest))
-	doConcurrentTest(t, new(concurrentTxStmtQueryTest))
-	doConcurrentTest(t, new(concurrentTxStmtExecTest))
-	doConcurrentTest(t, new(concurrentRandomTest))
+	list := []struct {
+		name string
+		ct   concurrentTest
+	}{
+		{"Query", new(concurrentDBQueryTest)},
+		{"Exec", new(concurrentDBExecTest)},
+		{"StmtQuery", new(concurrentStmtQueryTest)},
+		{"StmtExec", new(concurrentStmtExecTest)},
+		{"TxQuery", new(concurrentTxQueryTest)},
+		{"TxExec", new(concurrentTxExecTest)},
+		{"TxStmtQuery", new(concurrentTxStmtQueryTest)},
+		{"TxStmtExec", new(concurrentTxStmtExecTest)},
+		{"Random", new(concurrentRandomTest)},
+	}
+	for _, item := range list {
+		t.Run(item.name, func(t *testing.T) {
+			doConcurrentTest(t, item.ct)
+		})
+	}
 }
 
 func TestConnectionLeak(t *testing.T) {
@@ -2874,6 +3341,131 @@
 	wg.Wait()
 }
 
+type nvcDriver struct {
+	fakeDriver
+	skipNamedValueCheck bool
+}
+
+func (d *nvcDriver) Open(dsn string) (driver.Conn, error) {
+	c, err := d.fakeDriver.Open(dsn)
+	fc := c.(*fakeConn)
+	fc.db.allowAny = true
+	return &nvcConn{fc, d.skipNamedValueCheck}, err
+}
+
+type nvcConn struct {
+	*fakeConn
+	skipNamedValueCheck bool
+}
+
+type decimal struct {
+	value int
+}
+
+type doNotInclude struct{}
+
+var _ driver.NamedValueChecker = &nvcConn{}
+
+func (c *nvcConn) CheckNamedValue(nv *driver.NamedValue) error {
+	if c.skipNamedValueCheck {
+		return driver.ErrSkip
+	}
+	switch v := nv.Value.(type) {
+	default:
+		return driver.ErrSkip
+	case Out:
+		switch ov := v.Dest.(type) {
+		default:
+			return errors.New("unkown NameValueCheck OUTPUT type")
+		case *string:
+			*ov = "from-server"
+			nv.Value = "OUT:*string"
+		}
+		return nil
+	case decimal, []int64:
+		return nil
+	case doNotInclude:
+		return driver.ErrRemoveArgument
+	}
+}
+
+func TestNamedValueChecker(t *testing.T) {
+	Register("NamedValueCheck", &nvcDriver{})
+	db, err := Open("NamedValueCheck", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	_, err = db.ExecContext(ctx, "WIPE")
+	if err != nil {
+		t.Fatal("exec wipe", err)
+	}
+
+	_, err = db.ExecContext(ctx, "CREATE|keys|dec1=any,str1=string,out1=string,array1=any")
+	if err != nil {
+		t.Fatal("exec create", err)
+	}
+
+	o1 := ""
+	_, err = db.ExecContext(ctx, "INSERT|keys|dec1=?A,str1=?,out1=?O1,array1=?", Named("A", decimal{123}), "hello", Named("O1", Out{Dest: &o1}), []int64{42, 128, 707}, doNotInclude{})
+	if err != nil {
+		t.Fatal("exec insert", err)
+	}
+	var (
+		str1 string
+		dec1 decimal
+		arr1 []int64
+	)
+	err = db.QueryRowContext(ctx, "SELECT|keys|dec1,str1,array1|").Scan(&dec1, &str1, &arr1)
+	if err != nil {
+		t.Fatal("select", err)
+	}
+
+	list := []struct{ got, want interface{} }{
+		{o1, "from-server"},
+		{dec1, decimal{123}},
+		{str1, "hello"},
+		{arr1, []int64{42, 128, 707}},
+	}
+
+	for index, item := range list {
+		if !reflect.DeepEqual(item.got, item.want) {
+			t.Errorf("got %#v wanted %#v for index %d", item.got, item.want, index)
+		}
+	}
+}
+
+func TestNamedValueCheckerSkip(t *testing.T) {
+	Register("NamedValueCheckSkip", &nvcDriver{skipNamedValueCheck: true})
+	db, err := Open("NamedValueCheckSkip", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	_, err = db.ExecContext(ctx, "WIPE")
+	if err != nil {
+		t.Fatal("exec wipe", err)
+	}
+
+	_, err = db.ExecContext(ctx, "CREATE|keys|dec1=any")
+	if err != nil {
+		t.Fatal("exec create", err)
+	}
+
+	_, err = db.ExecContext(ctx, "INSERT|keys|dec1=?A", Named("A", decimal{123}))
+	if err == nil {
+		t.Fatalf("expected error with bad argument, got %v", err)
+	}
+}
+
 // badConn implements a bad driver.Conn, for TestBadDriver.
 // The Exec method panics.
 type badConn struct{}
@@ -2965,6 +3557,24 @@
 	}
 }
 
+// Issue 18101.
+func TestTypedString(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	type Str string
+	var scanned Str
+
+	err := db.QueryRow("SELECT|people|name|name=?", "Alice").Scan(&scanned)
+	if err != nil {
+		t.Fatal(err)
+	}
+	expected := Str("Alice")
+	if scanned != expected {
+		t.Errorf("expected %+v, got %+v", expected, scanned)
+	}
+}
+
 func BenchmarkConcurrentDBExec(b *testing.B) {
 	b.ReportAllocs()
 	ct := new(concurrentDBExecTest)
diff --git a/libgo/go/debug/dwarf/export_test.go b/libgo/go/debug/dwarf/export_test.go
new file mode 100644
index 0000000..b8a25ff
--- /dev/null
+++ b/libgo/go/debug/dwarf/export_test.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package dwarf
+
+var PathJoin = pathJoin
diff --git a/libgo/go/debug/dwarf/line.go b/libgo/go/debug/dwarf/line.go
index ed82fee..4e6e142 100644
--- a/libgo/go/debug/dwarf/line.go
+++ b/libgo/go/debug/dwarf/line.go
@@ -9,6 +9,7 @@
 	"fmt"
 	"io"
 	"path"
+	"strings"
 )
 
 // A LineReader reads a sequence of LineEntry structures from a DWARF
@@ -247,10 +248,10 @@
 		if len(directory) == 0 {
 			break
 		}
-		if !path.IsAbs(directory) {
+		if !pathIsAbs(directory) {
 			// Relative paths are implicitly relative to
 			// the compilation directory.
-			directory = path.Join(r.directories[0], directory)
+			directory = pathJoin(r.directories[0], directory)
 		}
 		r.directories = append(r.directories, directory)
 	}
@@ -283,11 +284,11 @@
 	}
 	off := r.buf.off
 	dirIndex := int(r.buf.uint())
-	if !path.IsAbs(name) {
+	if !pathIsAbs(name) {
 		if dirIndex >= len(r.directories) {
 			return false, DecodeError{"line", off, "directory index too large"}
 		}
-		name = path.Join(r.directories[dirIndex], name)
+		name = pathJoin(r.directories[dirIndex], name)
 	}
 	mtime := r.buf.uint()
 	length := int(r.buf.uint())
@@ -588,3 +589,68 @@
 		*entry = next
 	}
 }
+
+// pathIsAbs returns whether path is an absolute path (or "full path
+// name" in DWARF parlance). This is in "whatever form makes sense for
+// the host system", so this accepts both UNIX-style and DOS-style
+// absolute paths. We avoid the filepath package because we want this
+// to behave the same regardless of our host system and because we
+// don't know what system the paths came from.
+func pathIsAbs(path string) bool {
+	_, path = splitDrive(path)
+	return len(path) > 0 && (path[0] == '/' || path[0] == '\\')
+}
+
+// pathJoin joins dirname and filename. filename must be relative.
+// DWARF paths can be UNIX-style or DOS-style, so this handles both.
+func pathJoin(dirname, filename string) string {
+	if len(dirname) == 0 {
+		return filename
+	}
+	// dirname should be absolute, which means we can determine
+	// whether it's a DOS path reasonably reliably by looking for
+	// a drive letter or UNC path.
+	drive, dirname := splitDrive(dirname)
+	if drive == "" {
+		// UNIX-style path.
+		return path.Join(dirname, filename)
+	}
+	// DOS-style path.
+	drive2, filename := splitDrive(filename)
+	if drive2 != "" {
+		if strings.ToLower(drive) != strings.ToLower(drive2) {
+			// Different drives. There's not much we can
+			// do here, so just ignore the directory.
+			return drive2 + filename
+		}
+		// Drives are the same. Ignore drive on filename.
+	}
+	if !(strings.HasSuffix(dirname, "/") || strings.HasSuffix(dirname, `\`)) && dirname != "" {
+		dirname += `\`
+	}
+	return drive + dirname + filename
+}
+
+// splitDrive splits the DOS drive letter or UNC share point from
+// path, if any. path == drive + rest
+func splitDrive(path string) (drive, rest string) {
+	if len(path) >= 2 && path[1] == ':' {
+		if c := path[0]; 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' {
+			return path[:2], path[2:]
+		}
+	}
+	if len(path) > 3 && (path[0] == '\\' || path[0] == '/') && (path[1] == '\\' || path[1] == '/') {
+		// Normalize the path so we can search for just \ below.
+		npath := strings.Replace(path, "/", `\`, -1)
+		// Get the host part, which must be non-empty.
+		slash1 := strings.IndexByte(npath[2:], '\\') + 2
+		if slash1 > 2 {
+			// Get the mount-point part, which must be non-empty.
+			slash2 := strings.IndexByte(npath[slash1+1:], '\\') + slash1 + 1
+			if slash2 > slash1 {
+				return path[:slash2], path[slash2:]
+			}
+		}
+	}
+	return "", path
+}
diff --git a/libgo/go/debug/dwarf/line_test.go b/libgo/go/debug/dwarf/line_test.go
index cc363f5..11a2544 100644
--- a/libgo/go/debug/dwarf/line_test.go
+++ b/libgo/go/debug/dwarf/line_test.go
@@ -7,6 +7,7 @@
 import (
 	. "debug/dwarf"
 	"io"
+	"strings"
 	"testing"
 )
 
@@ -46,6 +47,46 @@
 	testLineTable(t, want, elfData(t, "testdata/line-gcc.elf"))
 }
 
+func TestLineGCCWindows(t *testing.T) {
+	// Generated by:
+	//   > gcc --version
+	//   gcc (tdm64-1) 4.9.2
+	//   > gcc -g -o line-gcc-win.bin line1.c C:\workdir\go\src\debug\dwarf\testdata\line2.c
+
+	toWindows := func(lf *LineFile) *LineFile {
+		lf2 := *lf
+		lf2.Name = strings.Replace(lf2.Name, "/home/austin/go.dev/", "C:\\workdir\\go\\", -1)
+		lf2.Name = strings.Replace(lf2.Name, "/", "\\", -1)
+		return &lf2
+	}
+	file1C := toWindows(file1C)
+	file1H := toWindows(file1H)
+	file2C := toWindows(file2C)
+
+	// Line table based on objdump --dwarf=rawline,decodedline
+	want := []LineEntry{
+		{Address: 0x401530, File: file1H, Line: 2, IsStmt: true},
+		{Address: 0x401538, File: file1H, Line: 5, IsStmt: true},
+		{Address: 0x401541, File: file1H, Line: 6, IsStmt: true, Discriminator: 3},
+		{Address: 0x40154b, File: file1H, Line: 5, IsStmt: true, Discriminator: 3},
+		{Address: 0x40154f, File: file1H, Line: 5, IsStmt: false, Discriminator: 1},
+		{Address: 0x401555, File: file1H, Line: 7, IsStmt: true},
+		{Address: 0x40155b, File: file1C, Line: 6, IsStmt: true},
+		{Address: 0x401563, File: file1C, Line: 6, IsStmt: true},
+		{Address: 0x401568, File: file1C, Line: 7, IsStmt: true},
+		{Address: 0x40156d, File: file1C, Line: 8, IsStmt: true},
+		{Address: 0x401572, File: file1C, Line: 9, IsStmt: true},
+		{Address: 0x401578, EndSequence: true},
+
+		{Address: 0x401580, File: file2C, Line: 4, IsStmt: true},
+		{Address: 0x401588, File: file2C, Line: 5, IsStmt: true},
+		{Address: 0x401595, File: file2C, Line: 6, IsStmt: true},
+		{Address: 0x40159b, EndSequence: true},
+	}
+
+	testLineTable(t, want, peData(t, "testdata/line-gcc-win.bin"))
+}
+
 func TestLineELFClang(t *testing.T) {
 	// Generated by:
 	//   # clang --version | head -n1
@@ -183,6 +224,11 @@
 				}
 				t.Fatal("lr.Next:", err)
 			}
+			// Ignore sources from the Windows build environment.
+			if strings.HasPrefix(line.File.Name, "C:\\crossdev\\") ||
+				strings.HasPrefix(line.File.Name, "C:/crossdev/") {
+				continue
+			}
 			got = append(got, line)
 		}
 	}
@@ -227,3 +273,42 @@
 		t.Logf("  %+v File:%+v", l, l.File)
 	}
 }
+
+type joinTest struct {
+	dirname, filename string
+	path              string
+}
+
+var joinTests = []joinTest{
+	{"a", "b", "a/b"},
+	{"a", "", "a"},
+	{"", "b", "b"},
+	{"/a", "b", "/a/b"},
+	{"/a/", "b", "/a/b"},
+
+	{`C:\Windows\`, `System32`, `C:\Windows\System32`},
+	{`C:\Windows\`, ``, `C:\Windows\`},
+	{`C:\`, `Windows`, `C:\Windows`},
+	{`C:\Windows\`, `C:System32`, `C:\Windows\System32`},
+	{`C:\Windows`, `a/b`, `C:\Windows\a/b`},
+	{`\\host\share\`, `foo`, `\\host\share\foo`},
+	{`\\host\share\`, `foo\bar`, `\\host\share\foo\bar`},
+	{`//host/share/`, `foo/bar`, `//host/share/foo/bar`},
+
+	// The following are "best effort". We shouldn't see relative
+	// base directories in DWARF, but these test that pathJoin
+	// doesn't fail miserably if it sees one.
+	{`C:`, `a`, `C:a`},
+	{`C:`, `a\b`, `C:a\b`},
+	{`C:.`, `a`, `C:.\a`},
+	{`C:a`, `b`, `C:a\b`},
+}
+
+func TestPathJoin(t *testing.T) {
+	for _, test := range joinTests {
+		got := PathJoin(test.dirname, test.filename)
+		if test.path != got {
+			t.Errorf("pathJoin(%q, %q) = %q, want %q", test.dirname, test.filename, got, test.path)
+		}
+	}
+}
diff --git a/libgo/go/debug/dwarf/testdata/line-gcc-win.bin b/libgo/go/debug/dwarf/testdata/line-gcc-win.bin
new file mode 100644
index 0000000..583ad44
--- /dev/null
+++ b/libgo/go/debug/dwarf/testdata/line-gcc-win.bin
Binary files differ
diff --git a/libgo/go/debug/dwarf/type_test.go b/libgo/go/debug/dwarf/type_test.go
index 0283466..6c06731 100644
--- a/libgo/go/debug/dwarf/type_test.go
+++ b/libgo/go/debug/dwarf/type_test.go
@@ -8,6 +8,7 @@
 	. "debug/dwarf"
 	"debug/elf"
 	"debug/macho"
+	"debug/pe"
 	"testing"
 )
 
@@ -67,6 +68,19 @@
 	return d
 }
 
+func peData(t *testing.T, name string) *Data {
+	f, err := pe.Open(name)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	d, err := f.DWARF()
+	if err != nil {
+		t.Fatal(err)
+	}
+	return d
+}
+
 func TestTypedefsELF(t *testing.T) { testTypedefs(t, elfData(t, "testdata/typedef.elf"), "elf") }
 
 func TestTypedefsMachO(t *testing.T) {
diff --git a/libgo/go/debug/pe/file_cgo_test.go b/libgo/go/debug/pe/file_cgo_test.go
new file mode 100644
index 0000000..739671d
--- /dev/null
+++ b/libgo/go/debug/pe/file_cgo_test.go
@@ -0,0 +1,31 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+
+package pe
+
+import (
+	"os/exec"
+	"testing"
+)
+
+func testCgoDWARF(t *testing.T, linktype int) {
+	if _, err := exec.LookPath("gcc"); err != nil {
+		t.Skip("skipping test: gcc is missing")
+	}
+	testDWARF(t, linktype)
+}
+
+func TestDefaultLinkerDWARF(t *testing.T) {
+	testCgoDWARF(t, linkCgoDefault)
+}
+
+func TestInternalLinkerDWARF(t *testing.T) {
+	testCgoDWARF(t, linkCgoInternal)
+}
+
+func TestExternalLinkerDWARF(t *testing.T) {
+	testCgoDWARF(t, linkCgoExternal)
+}
diff --git a/libgo/go/debug/pe/file_test.go b/libgo/go/debug/pe/file_test.go
index 5a740c8..8645d67 100644
--- a/libgo/go/debug/pe/file_test.go
+++ b/libgo/go/debug/pe/file_test.go
@@ -12,8 +12,11 @@
 	"os/exec"
 	"path/filepath"
 	"reflect"
+	"regexp"
 	"runtime"
+	"strconv"
 	"testing"
+	"text/template"
 )
 
 type fileTest struct {
@@ -288,28 +291,70 @@
 	}
 }
 
-func TestDWARF(t *testing.T) {
+const (
+	linkNoCgo = iota
+	linkCgoDefault
+	linkCgoInternal
+	linkCgoExternal
+)
+
+func testDWARF(t *testing.T, linktype int) {
 	if runtime.GOOS != "windows" {
 		t.Skip("skipping windows only test")
 	}
+	testenv.MustHaveGoRun(t)
 
 	tmpdir, err := ioutil.TempDir("", "TestDWARF")
 	if err != nil {
-		t.Fatal("TempDir failed: ", err)
+		t.Fatal(err)
 	}
 	defer os.RemoveAll(tmpdir)
 
-	prog := `
-package main
-func main() {
-}
-`
 	src := filepath.Join(tmpdir, "a.go")
-	exe := filepath.Join(tmpdir, "a.exe")
-	err = ioutil.WriteFile(src, []byte(prog), 0644)
-	output, err := exec.Command(testenv.GoToolPath(t), "build", "-o", exe, src).CombinedOutput()
+	file, err := os.Create(src)
 	if err != nil {
-		t.Fatalf("building test executable failed: %s %s", err, output)
+		t.Fatal(err)
+	}
+	err = template.Must(template.New("main").Parse(testprog)).Execute(file, linktype != linkNoCgo)
+	if err != nil {
+		if err := file.Close(); err != nil {
+			t.Error(err)
+		}
+		t.Fatal(err)
+	}
+	if err := file.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	exe := filepath.Join(tmpdir, "a.exe")
+	args := []string{"build", "-o", exe}
+	switch linktype {
+	case linkNoCgo:
+	case linkCgoDefault:
+	case linkCgoInternal:
+		args = append(args, "-ldflags", "-linkmode=internal")
+	case linkCgoExternal:
+		args = append(args, "-ldflags", "-linkmode=external")
+	default:
+		t.Fatalf("invalid linktype parameter of %v", linktype)
+	}
+	args = append(args, src)
+	out, err := exec.Command(testenv.GoToolPath(t), args...).CombinedOutput()
+	if err != nil {
+		t.Fatalf("building test executable for linktype %d failed: %s %s", linktype, err, out)
+	}
+	out, err = exec.Command(exe).CombinedOutput()
+	if err != nil {
+		t.Fatalf("running test executable failed: %s %s", err, out)
+	}
+
+	matches := regexp.MustCompile("main=(.*)\n").FindStringSubmatch(string(out))
+	if len(matches) < 2 {
+		t.Fatalf("unexpected program output: %s", out)
+	}
+	wantaddr, err := strconv.ParseUint(matches[1], 0, 64)
+	if err != nil {
+		t.Fatalf("unexpected main address %q: %s", matches[1], err)
 	}
 
 	f, err := Open(exe)
@@ -318,6 +363,16 @@
 	}
 	defer f.Close()
 
+	var foundDebugGDBScriptsSection bool
+	for _, sect := range f.Sections {
+		if sect.Name == ".debug_gdb_scripts" {
+			foundDebugGDBScriptsSection = true
+		}
+	}
+	if !foundDebugGDBScriptsSection {
+		t.Error(".debug_gdb_scripts section is not found")
+	}
+
 	d, err := f.DWARF()
 	if err != nil {
 		t.Fatal(err)
@@ -334,8 +389,8 @@
 			break
 		}
 		if e.Tag == dwarf.TagSubprogram {
-			for _, f := range e.Field {
-				if f.Attr == dwarf.AttrName && e.Val(dwarf.AttrName) == "main.main" {
+			if name, ok := e.Val(dwarf.AttrName).(string); ok && name == "main.main" {
+				if addr, ok := e.Val(dwarf.AttrLowpc).(uint64); ok && addr == wantaddr {
 					return
 				}
 			}
@@ -415,3 +470,65 @@
 		}
 	}
 }
+
+func TestDWARF(t *testing.T) {
+	testDWARF(t, linkNoCgo)
+}
+
+const testprog = `
+package main
+
+import "fmt"
+{{if .}}import "C"
+{{end}}
+
+func main() {
+	fmt.Printf("main=%p\n", main)
+}
+`
+
+func TestBuildingWindowsGUI(t *testing.T) {
+	testenv.MustHaveGoBuild(t)
+
+	if runtime.GOOS != "windows" {
+		t.Skip("skipping windows only test")
+	}
+	tmpdir, err := ioutil.TempDir("", "TestBuildingWindowsGUI")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(tmpdir)
+
+	src := filepath.Join(tmpdir, "a.go")
+	err = ioutil.WriteFile(src, []byte(`package main; func main() {}`), 0644)
+	if err != nil {
+		t.Fatal(err)
+	}
+	exe := filepath.Join(tmpdir, "a.exe")
+	cmd := exec.Command(testenv.GoToolPath(t), "build", "-ldflags", "-H=windowsgui", "-o", exe, src)
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("building test executable failed: %s %s", err, out)
+	}
+
+	f, err := Open(exe)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+
+	const _IMAGE_SUBSYSTEM_WINDOWS_GUI = 2
+
+	switch oh := f.OptionalHeader.(type) {
+	case *OptionalHeader32:
+		if oh.Subsystem != _IMAGE_SUBSYSTEM_WINDOWS_GUI {
+			t.Errorf("unexpected Subsystem value: have %d, but want %d", oh.Subsystem, _IMAGE_SUBSYSTEM_WINDOWS_GUI)
+		}
+	case *OptionalHeader64:
+		if oh.Subsystem != _IMAGE_SUBSYSTEM_WINDOWS_GUI {
+			t.Errorf("unexpected Subsystem value: have %d, but want %d", oh.Subsystem, _IMAGE_SUBSYSTEM_WINDOWS_GUI)
+		}
+	default:
+		t.Fatalf("unexpected OptionalHeader type: have %T, but want *pe.OptionalHeader32 or *pe.OptionalHeader64", oh)
+	}
+}
diff --git a/libgo/go/encoding/ascii85/ascii85_test.go b/libgo/go/encoding/ascii85/ascii85_test.go
index aad199b..1a3a87a 100644
--- a/libgo/go/encoding/ascii85/ascii85_test.go
+++ b/libgo/go/encoding/ascii85/ascii85_test.go
@@ -16,6 +16,18 @@
 	decoded, encoded string
 }
 
+var bigtest = testpair{
+	"Man is distinguished, not only by his reason, but by this singular passion from " +
+		"other animals, which is a lust of the mind, that by a perseverance of delight in " +
+		"the continued and indefatigable generation of knowledge, exceeds the short " +
+		"vehemence of any carnal pleasure.",
+	"9jqo^BlbD-BleB1DJ+*+F(f,q/0JhKF<GL>Cj@.4Gp$d7F!,L7@<6@)/0JDEF<G%<+EV:2F!,\n" +
+		"O<DJ+*.@<*K0@<6L(Df-\\0Ec5e;DffZ(EZee.Bl.9pF\"AGXBPCsi+DGm>@3BB/F*&OCAfu2/AKY\n" +
+		"i(DIb:@FD,*)+C]U=@3BN#EcYf8ATD3s@q?d$AftVqCh[NqF<G:8+EV:.+Cf>-FD5W8ARlolDIa\n" +
+		"l(DId<j@<?3r@:F%a+D58'ATD4$Bl@l3De:,-DJs`8ARoFb/0JMK@qB4^F!,R<AKZ&-DfTqBG%G\n" +
+		">uD.RTpAKYo'+CT/5+Cei#DII?(E,9)oF*2M7/c\n",
+}
+
 var pairs = []testpair{
 	// Encode returns 0 when len(src) is 0
 	{
@@ -23,17 +35,7 @@
 		"",
 	},
 	// Wikipedia example
-	{
-		"Man is distinguished, not only by his reason, but by this singular passion from " +
-			"other animals, which is a lust of the mind, that by a perseverance of delight in " +
-			"the continued and indefatigable generation of knowledge, exceeds the short " +
-			"vehemence of any carnal pleasure.",
-		"9jqo^BlbD-BleB1DJ+*+F(f,q/0JhKF<GL>Cj@.4Gp$d7F!,L7@<6@)/0JDEF<G%<+EV:2F!,\n" +
-			"O<DJ+*.@<*K0@<6L(Df-\\0Ec5e;DffZ(EZee.Bl.9pF\"AGXBPCsi+DGm>@3BB/F*&OCAfu2/AKY\n" +
-			"i(DIb:@FD,*)+C]U=@3BN#EcYf8ATD3s@q?d$AftVqCh[NqF<G:8+EV:.+Cf>-FD5W8ARlolDIa\n" +
-			"l(DId<j@<?3r@:F%a+D58'ATD4$Bl@l3De:,-DJs`8ARoFb/0JMK@qB4^F!,R<AKZ&-DfTqBG%G\n" +
-			">uD.RTpAKYo'+CT/5+Cei#DII?(E,9)oF*2M7/c\n",
-	},
+	bigtest,
 	// Special case when shortening !!!!! to z.
 	{
 		"\000\000\000\000",
@@ -41,9 +43,8 @@
 	},
 }
 
-var bigtest = pairs[len(pairs)-1]
-
 func testEqual(t *testing.T, msg string, args ...interface{}) bool {
+	t.Helper()
 	if args[len(args)-2] != args[len(args)-1] {
 		t.Errorf(msg, args...)
 		return false
@@ -134,11 +135,15 @@
 		decoder := NewDecoder(strings.NewReader(bigtest.encoded))
 		buf := make([]byte, len(bigtest.decoded)+12)
 		var total int
-		for total = 0; total < len(bigtest.decoded); {
-			n, err := decoder.Read(buf[total : total+bs])
-			testEqual(t, "Read from %q at pos %d = %d, %v, want _, %v", bigtest.encoded, total, n, err, error(nil))
+		var n int
+		var err error
+		for total = 0; total < len(bigtest.decoded) && err == nil; {
+			n, err = decoder.Read(buf[total : total+bs])
 			total += n
 		}
+		if err != nil && err != io.EOF {
+			t.Errorf("Read from %q at pos %d = %d, unexpected error %v", bigtest.encoded, total, n, err)
+		}
 		testEqual(t, "Decoding/%d of %q = %q, want %q", bs, bigtest.encoded, string(buf[0:total]), bigtest.decoded)
 	}
 }
diff --git a/libgo/go/encoding/asn1/asn1.go b/libgo/go/encoding/asn1/asn1.go
index 044f74a..b8e2770 100644
--- a/libgo/go/encoding/asn1/asn1.go
+++ b/libgo/go/encoding/asn1/asn1.go
@@ -22,6 +22,7 @@
 import (
 	"errors"
 	"fmt"
+	"math"
 	"math/big"
 	"reflect"
 	"strconv"
@@ -206,6 +207,14 @@
 	return
 }
 
+// NULL
+
+// NullRawValue is a RawValue with its Tag set to the ASN.1 NULL type tag (5).
+var NullRawValue = RawValue{Tag: TagNull}
+
+// NullBytes contains bytes representing the DER-encoded ASN.1 NULL type.
+var NullBytes = []byte{TagNull, 0}
+
 // OBJECT IDENTIFIER
 
 // An ObjectIdentifier represents an ASN.1 OBJECT IDENTIFIER.
@@ -293,16 +302,24 @@
 // given byte slice. It returns the value and the new offset.
 func parseBase128Int(bytes []byte, initOffset int) (ret, offset int, err error) {
 	offset = initOffset
+	var ret64 int64
 	for shifted := 0; offset < len(bytes); shifted++ {
-		if shifted == 4 {
+		// 5 * 7 bits per byte == 35 bits of data
+		// Thus the representation is either non-minimal or too large for an int32
+		if shifted == 5 {
 			err = StructuralError{"base 128 integer too large"}
 			return
 		}
-		ret <<= 7
+		ret64 <<= 7
 		b := bytes[offset]
-		ret |= int(b & 0x7f)
+		ret64 |= int64(b & 0x7f)
 		offset++
 		if b&0x80 == 0 {
+			ret = int(ret64)
+			// Ensure that the returned value fits in an int on all platforms
+			if ret64 > math.MaxInt32 {
+				err = StructuralError{"base 128 integer too large"}
+			}
 			return
 		}
 	}
@@ -975,12 +992,12 @@
 //
 // The following tags on struct fields have special meaning to Unmarshal:
 //
-//	application	specifies that a APPLICATION tag is used
-//	default:x	sets the default value for optional integer fields (only used if optional is also present)
-//	explicit	specifies that an additional, explicit tag wraps the implicit one
-//	optional	marks the field as ASN.1 OPTIONAL
-//	set		causes a SET, rather than a SEQUENCE type to be expected
-//	tag:x		specifies the ASN.1 tag number; implies ASN.1 CONTEXT SPECIFIC
+//	application specifies that a APPLICATION tag is used
+//	default:x   sets the default value for optional integer fields (only used if optional is also present)
+//	explicit    specifies that an additional, explicit tag wraps the implicit one
+//	optional    marks the field as ASN.1 OPTIONAL
+//	set         causes a SET, rather than a SEQUENCE type to be expected
+//	tag:x       specifies the ASN.1 tag number; implies ASN.1 CONTEXT SPECIFIC
 //
 // If the type of the first field of a structure is RawContent then the raw
 // ASN1 contents of the struct will be stored in it.
diff --git a/libgo/go/encoding/asn1/asn1_test.go b/libgo/go/encoding/asn1/asn1_test.go
index 9976656..c9eda40 100644
--- a/libgo/go/encoding/asn1/asn1_test.go
+++ b/libgo/go/encoding/asn1/asn1_test.go
@@ -7,6 +7,7 @@
 import (
 	"bytes"
 	"fmt"
+	"math"
 	"math/big"
 	"reflect"
 	"strings"
@@ -386,6 +387,8 @@
 	{[]byte{0xa0, 0x81, 0x7f}, false, tagAndLength{}},
 	// Tag numbers which would overflow int32 are rejected. (The value below is 2^31.)
 	{[]byte{0x1f, 0x88, 0x80, 0x80, 0x80, 0x00, 0x00}, false, tagAndLength{}},
+	// Tag numbers that fit in an int32 are valid. (The value below is 2^31 - 1.)
+	{[]byte{0x1f, 0x87, 0xFF, 0xFF, 0xFF, 0x7F, 0x00}, true, tagAndLength{tag: math.MaxInt32}},
 	// Long tag number form may not be used for tags that fit in short form.
 	{[]byte{0x1f, 0x1e, 0x00}, false, tagAndLength{}},
 }
@@ -476,6 +479,7 @@
 	out interface{}
 }{
 	{[]byte{0x02, 0x01, 0x42}, newInt(0x42)},
+	{[]byte{0x05, 0x00}, &RawValue{0, 5, false, []byte{}, []byte{0x05, 0x00}}},
 	{[]byte{0x30, 0x08, 0x06, 0x06, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d}, &TestObjectIdentifierStruct{[]int{1, 2, 840, 113549}}},
 	{[]byte{0x03, 0x04, 0x06, 0x6e, 0x5d, 0xc0}, &BitString{[]byte{110, 93, 192}, 18}},
 	{[]byte{0x30, 0x09, 0x02, 0x01, 0x01, 0x02, 0x01, 0x02, 0x02, 0x01, 0x03}, &[]int{1, 2, 3}},
@@ -1004,3 +1008,28 @@
 		t.Errorf("got %v, want %v", err, want)
 	}
 }
+
+func TestNull(t *testing.T) {
+	marshaled, err := Marshal(NullRawValue)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(NullBytes, marshaled) {
+		t.Errorf("Expected Marshal of NullRawValue to yeild %x, got %x", NullBytes, marshaled)
+	}
+
+	unmarshaled := RawValue{}
+	if _, err := Unmarshal(NullBytes, &unmarshaled); err != nil {
+		t.Fatal(err)
+	}
+
+	unmarshaled.FullBytes = NullRawValue.FullBytes
+	if len(unmarshaled.Bytes) == 0 {
+		// DeepEqual considers a nil slice and an empty slice to be different.
+		unmarshaled.Bytes = NullRawValue.Bytes
+	}
+
+	if !reflect.DeepEqual(NullRawValue, unmarshaled) {
+		t.Errorf("Expected Unmarshal of NullBytes to yield %v, got %v", NullRawValue, unmarshaled)
+	}
+}
diff --git a/libgo/go/encoding/asn1/common.go b/libgo/go/encoding/asn1/common.go
index 0695180..cd93b27 100644
--- a/libgo/go/encoding/asn1/common.go
+++ b/libgo/go/encoding/asn1/common.go
@@ -24,6 +24,7 @@
 	TagInteger         = 2
 	TagBitString       = 3
 	TagOctetString     = 4
+	TagNull            = 5
 	TagOID             = 6
 	TagEnum            = 10
 	TagUTF8String      = 12
diff --git a/libgo/go/encoding/asn1/marshal.go b/libgo/go/encoding/asn1/marshal.go
index 225fd08..fdadb39 100644
--- a/libgo/go/encoding/asn1/marshal.go
+++ b/libgo/go/encoding/asn1/marshal.go
@@ -643,10 +643,12 @@
 // In addition to the struct tags recognised by Unmarshal, the following can be
 // used:
 //
-//	ia5:		causes strings to be marshaled as ASN.1, IA5 strings
-//	omitempty:	causes empty slices to be skipped
-//	printable:	causes strings to be marshaled as ASN.1, PrintableString strings.
-//	utf8:		causes strings to be marshaled as ASN.1, UTF8 strings
+//	ia5:         causes strings to be marshaled as ASN.1, IA5String values
+//	omitempty:   causes empty slices to be skipped
+//	printable:   causes strings to be marshaled as ASN.1, PrintableString values
+//	utf8:        causes strings to be marshaled as ASN.1, UTF8String values
+//	utc:         causes time.Time to be marshaled as ASN.1, UTCTime values
+//	generalized: causes time.Time to be marshaled as ASN.1, GeneralizedTime values
 func Marshal(val interface{}) ([]byte, error) {
 	e, err := makeField(reflect.ValueOf(val), fieldParameters{})
 	if err != nil {
diff --git a/libgo/go/encoding/base32/base32.go b/libgo/go/encoding/base32/base32.go
index c193e65..bf341b5 100644
--- a/libgo/go/encoding/base32/base32.go
+++ b/libgo/go/encoding/base32/base32.go
@@ -23,8 +23,14 @@
 type Encoding struct {
 	encode    string
 	decodeMap [256]byte
+	padChar   rune
 }
 
+const (
+	StdPadding rune = '=' // Standard padding character
+	NoPadding  rune = -1  // No padding
+)
+
 const encodeStd = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567"
 const encodeHex = "0123456789ABCDEFGHIJKLMNOPQRSTUV"
 
@@ -33,6 +39,8 @@
 func NewEncoding(encoder string) *Encoding {
 	e := new(Encoding)
 	e.encode = encoder
+	e.padChar = StdPadding
+
 	for i := 0; i < len(e.decodeMap); i++ {
 		e.decodeMap[i] = 0xFF
 	}
@@ -57,6 +65,26 @@
 	return r
 }
 
+// WithPadding creates a new encoding identical to enc except
+// with a specified padding character, or NoPadding to disable padding.
+// The padding character must not be '\r' or '\n', must not
+// be contained in the encoding's alphabet and must be a rune equal or
+// below '\xff'.
+func (enc Encoding) WithPadding(padding rune) *Encoding {
+	if padding == '\r' || padding == '\n' || padding > 0xff {
+		panic("invalid padding")
+	}
+
+	for i := 0; i < len(enc.encode); i++ {
+		if rune(enc.encode[i]) == padding {
+			panic("padding contained in alphabet")
+		}
+	}
+
+	enc.padChar = padding
+	return &enc
+}
+
 /*
  * Encoder
  */
@@ -73,60 +101,63 @@
 	}
 
 	for len(src) > 0 {
-		var b0, b1, b2, b3, b4, b5, b6, b7 byte
+		var b [8]byte
 
 		// Unpack 8x 5-bit source blocks into a 5 byte
 		// destination quantum
 		switch len(src) {
 		default:
-			b7 = src[4] & 0x1F
-			b6 = src[4] >> 5
+			b[7] = src[4] & 0x1F
+			b[6] = src[4] >> 5
 			fallthrough
 		case 4:
-			b6 |= (src[3] << 3) & 0x1F
-			b5 = (src[3] >> 2) & 0x1F
-			b4 = src[3] >> 7
+			b[6] |= (src[3] << 3) & 0x1F
+			b[5] = (src[3] >> 2) & 0x1F
+			b[4] = src[3] >> 7
 			fallthrough
 		case 3:
-			b4 |= (src[2] << 1) & 0x1F
-			b3 = (src[2] >> 4) & 0x1F
+			b[4] |= (src[2] << 1) & 0x1F
+			b[3] = (src[2] >> 4) & 0x1F
 			fallthrough
 		case 2:
-			b3 |= (src[1] << 4) & 0x1F
-			b2 = (src[1] >> 1) & 0x1F
-			b1 = (src[1] >> 6) & 0x1F
+			b[3] |= (src[1] << 4) & 0x1F
+			b[2] = (src[1] >> 1) & 0x1F
+			b[1] = (src[1] >> 6) & 0x1F
 			fallthrough
 		case 1:
-			b1 |= (src[0] << 2) & 0x1F
-			b0 = src[0] >> 3
+			b[1] |= (src[0] << 2) & 0x1F
+			b[0] = src[0] >> 3
 		}
 
 		// Encode 5-bit blocks using the base32 alphabet
-		dst[0] = enc.encode[b0]
-		dst[1] = enc.encode[b1]
-		dst[2] = enc.encode[b2]
-		dst[3] = enc.encode[b3]
-		dst[4] = enc.encode[b4]
-		dst[5] = enc.encode[b5]
-		dst[6] = enc.encode[b6]
-		dst[7] = enc.encode[b7]
+		for i := 0; i < 8; i++ {
+			if len(dst) > i {
+				dst[i] = enc.encode[b[i]]
+			}
+		}
 
 		// Pad the final quantum
 		if len(src) < 5 {
-			dst[7] = '='
+			if enc.padChar == NoPadding {
+				break
+			}
+
+			dst[7] = byte(enc.padChar)
 			if len(src) < 4 {
-				dst[6] = '='
-				dst[5] = '='
+				dst[6] = byte(enc.padChar)
+				dst[5] = byte(enc.padChar)
 				if len(src) < 3 {
-					dst[4] = '='
+					dst[4] = byte(enc.padChar)
 					if len(src) < 2 {
-						dst[3] = '='
-						dst[2] = '='
+						dst[3] = byte(enc.padChar)
+						dst[2] = byte(enc.padChar)
 					}
 				}
 			}
+
 			break
 		}
+
 		src = src[5:]
 		dst = dst[8:]
 	}
@@ -219,7 +250,12 @@
 
 // EncodedLen returns the length in bytes of the base32 encoding
 // of an input buffer of length n.
-func (enc *Encoding) EncodedLen(n int) int { return (n + 4) / 5 * 8 }
+func (enc *Encoding) EncodedLen(n int) int {
+	if enc.padChar == NoPadding {
+		return (n*8 + 4) / 5
+	}
+	return (n + 4) / 5 * 8
+}
 
 /*
  * Decoder
@@ -243,19 +279,28 @@
 		dlen := 8
 
 		for j := 0; j < 8; {
-			if len(src) == 0 {
+
+			// We have reached the end and are missing padding
+			if len(src) == 0 && enc.padChar != NoPadding {
 				return n, false, CorruptInputError(olen - len(src) - j)
 			}
+
+			// We have reached the end and are not expecing any padding
+			if len(src) == 0 && enc.padChar == NoPadding {
+				dlen, end = j, true
+				break
+			}
+
 			in := src[0]
 			src = src[1:]
-			if in == '=' && j >= 2 && len(src) < 8 {
+			if in == byte(enc.padChar) && j >= 2 && len(src) < 8 {
 				// We've reached the end and there's padding
 				if len(src)+j < 8-1 {
 					// not enough padding
 					return n, false, CorruptInputError(olen)
 				}
 				for k := 0; k < 8-1-j; k++ {
-					if len(src) > k && src[k] != '=' {
+					if len(src) > k && src[k] != byte(enc.padChar) {
 						// incorrect padding
 						return n, false, CorruptInputError(olen - len(src) + k - 1)
 					}
@@ -296,7 +341,11 @@
 		case 2:
 			dst[0] = dbuf[0]<<3 | dbuf[1]>>2
 		}
-		dst = dst[5:]
+
+		if !end {
+			dst = dst[5:]
+		}
+
 		switch dlen {
 		case 2:
 			n += 1
@@ -343,18 +392,33 @@
 	outbuf [1024 / 8 * 5]byte
 }
 
-func (d *decoder) Read(p []byte) (n int, err error) {
-	if d.err != nil {
-		return 0, d.err
+func readEncodedData(r io.Reader, buf []byte, min int) (n int, err error) {
+	for n < min && err == nil {
+		var nn int
+		nn, err = r.Read(buf[n:])
+		n += nn
 	}
+	if n < min && n > 0 && err == io.EOF {
+		err = io.ErrUnexpectedEOF
+	}
+	return
+}
 
+func (d *decoder) Read(p []byte) (n int, err error) {
 	// Use leftover decoded output from last read.
 	if len(d.out) > 0 {
 		n = copy(p, d.out)
 		d.out = d.out[n:]
+		if len(d.out) == 0 {
+			return n, d.err
+		}
 		return n, nil
 	}
 
+	if d.err != nil {
+		return 0, d.err
+	}
+
 	// Read a chunk.
 	nn := len(p) / 5 * 8
 	if nn < 8 {
@@ -363,7 +427,8 @@
 	if nn > len(d.buf) {
 		nn = len(d.buf)
 	}
-	nn, d.err = io.ReadAtLeast(d.r, d.buf[d.nbuf:nn], 8-d.nbuf)
+
+	nn, d.err = readEncodedData(d.r, d.buf[d.nbuf:nn], 8-d.nbuf)
 	d.nbuf += nn
 	if d.nbuf < 8 {
 		return 0, d.err
@@ -373,21 +438,30 @@
 	nr := d.nbuf / 8 * 8
 	nw := d.nbuf / 8 * 5
 	if nw > len(p) {
-		nw, d.end, d.err = d.enc.decode(d.outbuf[0:], d.buf[0:nr])
+		nw, d.end, err = d.enc.decode(d.outbuf[0:], d.buf[0:nr])
 		d.out = d.outbuf[0:nw]
 		n = copy(p, d.out)
 		d.out = d.out[n:]
 	} else {
-		n, d.end, d.err = d.enc.decode(p, d.buf[0:nr])
+		n, d.end, err = d.enc.decode(p, d.buf[0:nr])
 	}
 	d.nbuf -= nr
 	for i := 0; i < d.nbuf; i++ {
 		d.buf[i] = d.buf[i+nr]
 	}
 
-	if d.err == nil {
+	if err != nil && (d.err == nil || d.err == io.EOF) {
 		d.err = err
 	}
+
+	if len(d.out) > 0 {
+		// We cannot return all the decoded bytes to the caller in this
+		// invocation of Read, so we return a nil error to ensure that Read
+		// will be called again.  The error stored in d.err, if any, will be
+		// returned with the last set of decoded bytes.
+		return n, nil
+	}
+
 	return n, d.err
 }
 
@@ -407,7 +481,7 @@
 				offset++
 			}
 		}
-		if offset > 0 {
+		if err != nil || offset > 0 {
 			return offset, err
 		}
 		// Previous buffer entirely whitespace, read again
@@ -423,4 +497,10 @@
 
 // DecodedLen returns the maximum length in bytes of the decoded data
 // corresponding to n bytes of base32-encoded data.
-func (enc *Encoding) DecodedLen(n int) int { return n / 8 * 5 }
+func (enc *Encoding) DecodedLen(n int) int {
+	if enc.padChar == NoPadding {
+		return n * 5 / 8
+	}
+
+	return n / 8 * 5
+}
diff --git a/libgo/go/encoding/base32/base32_test.go b/libgo/go/encoding/base32/base32_test.go
index 66a48a3..56b229d 100644
--- a/libgo/go/encoding/base32/base32_test.go
+++ b/libgo/go/encoding/base32/base32_test.go
@@ -6,6 +6,7 @@
 
 import (
 	"bytes"
+	"errors"
 	"io"
 	"io/ioutil"
 	"strings"
@@ -43,6 +44,7 @@
 }
 
 func testEqual(t *testing.T, msg string, args ...interface{}) bool {
+	t.Helper()
 	if args[len(args)-2] != args[len(args)-1] {
 		t.Errorf(msg, args...)
 		return false
@@ -123,16 +125,174 @@
 	}
 }
 
+type badReader struct {
+	data   []byte
+	errs   []error
+	called int
+	limit  int
+}
+
+// Populates p with data, returns a count of the bytes written and an
+// error.  The error returned is taken from badReader.errs, with each
+// invocation of Read returning the next error in this slice, or io.EOF,
+// if all errors from the slice have already been returned.  The
+// number of bytes returned is determined by the size of the input buffer
+// the test passes to decoder.Read and will be a multiple of 8, unless
+// badReader.limit is non zero.
+func (b *badReader) Read(p []byte) (int, error) {
+	lim := len(p)
+	if b.limit != 0 && b.limit < lim {
+		lim = b.limit
+	}
+	if len(b.data) < lim {
+		lim = len(b.data)
+	}
+	for i := range p[:lim] {
+		p[i] = b.data[i]
+	}
+	b.data = b.data[lim:]
+	err := io.EOF
+	if b.called < len(b.errs) {
+		err = b.errs[b.called]
+	}
+	b.called++
+	return lim, err
+}
+
+// TestIssue20044 tests that decoder.Read behaves correctly when the caller
+// supplied reader returns an error.
+func TestIssue20044(t *testing.T) {
+	badErr := errors.New("bad reader error")
+	testCases := []struct {
+		r       badReader
+		res     string
+		err     error
+		dbuflen int
+	}{
+		// Check valid input data accompanied by an error is processed and the error is propagated.
+		{r: badReader{data: []byte("MY======"), errs: []error{badErr}},
+			res: "f", err: badErr},
+		// Check a read error accompanied by input data consisting of newlines only is propagated.
+		{r: badReader{data: []byte("\n\n\n\n\n\n\n\n"), errs: []error{badErr, nil}},
+			res: "", err: badErr},
+		// Reader will be called twice.  The first time it will return 8 newline characters.  The
+		// second time valid base32 encoded data and an error.  The data should be decoded
+		// correctly and the error should be propagated.
+		{r: badReader{data: []byte("\n\n\n\n\n\n\n\nMY======"), errs: []error{nil, badErr}},
+			res: "f", err: badErr, dbuflen: 8},
+		// Reader returns invalid input data (too short) and an error.  Verify the reader
+		// error is returned.
+		{r: badReader{data: []byte("MY====="), errs: []error{badErr}},
+			res: "", err: badErr},
+		// Reader returns invalid input data (too short) but no error.  Verify io.ErrUnexpectedEOF
+		// is returned.
+		{r: badReader{data: []byte("MY====="), errs: []error{nil}},
+			res: "", err: io.ErrUnexpectedEOF},
+		// Reader returns invalid input data and an error.  Verify the reader and not the
+		// decoder error is returned.
+		{r: badReader{data: []byte("Ma======"), errs: []error{badErr}},
+			res: "", err: badErr},
+		// Reader returns valid data and io.EOF.  Check data is decoded and io.EOF is propagated.
+		{r: badReader{data: []byte("MZXW6YTB"), errs: []error{io.EOF}},
+			res: "fooba", err: io.EOF},
+		// Check errors are properly reported when decoder.Read is called multiple times.
+		// decoder.Read will be called 8 times, badReader.Read will be called twice, returning
+		// valid data both times but an error on the second call.
+		{r: badReader{data: []byte("NRSWC43VOJSS4==="), errs: []error{nil, badErr}},
+			res: "leasure.", err: badErr, dbuflen: 1},
+		// Check io.EOF is properly reported when decoder.Read is called multiple times.
+		// decoder.Read will be called 8 times, badReader.Read will be called twice, returning
+		// valid data both times but io.EOF on the second call.
+		{r: badReader{data: []byte("NRSWC43VOJSS4==="), errs: []error{nil, io.EOF}},
+			res: "leasure.", err: io.EOF, dbuflen: 1},
+		// The following two test cases check that errors are propagated correctly when more than
+		// 8 bytes are read at a time.
+		{r: badReader{data: []byte("NRSWC43VOJSS4==="), errs: []error{io.EOF}},
+			res: "leasure.", err: io.EOF, dbuflen: 11},
+		{r: badReader{data: []byte("NRSWC43VOJSS4==="), errs: []error{badErr}},
+			res: "leasure.", err: badErr, dbuflen: 11},
+		// Check that errors are correctly propagated when the reader returns valid bytes in
+		// groups that are not divisible by 8.  The first read will return 11 bytes and no
+		// error.  The second will return 7 and an error.  The data should be decoded correctly
+		// and the error should be propagated.
+		{r: badReader{data: []byte("NRSWC43VOJSS4==="), errs: []error{nil, badErr}, limit: 11},
+			res: "leasure.", err: badErr},
+	}
+
+	for _, tc := range testCases {
+		input := tc.r.data
+		decoder := NewDecoder(StdEncoding, &tc.r)
+		var dbuflen int
+		if tc.dbuflen > 0 {
+			dbuflen = tc.dbuflen
+		} else {
+			dbuflen = StdEncoding.DecodedLen(len(input))
+		}
+		dbuf := make([]byte, dbuflen)
+		var err error
+		var res []byte
+		for err == nil {
+			var n int
+			n, err = decoder.Read(dbuf)
+			if n > 0 {
+				res = append(res, dbuf[:n]...)
+			}
+		}
+
+		testEqual(t, "Decoding of %q = %q, want %q", string(input), string(res), tc.res)
+		testEqual(t, "Decoding of %q err = %v, expected %v", string(input), err, tc.err)
+	}
+}
+
+// TestDecoderError verifies decode errors are propagated when there are no read
+// errors.
+func TestDecoderError(t *testing.T) {
+	for _, readErr := range []error{io.EOF, nil} {
+		input := "MZXW6YTb"
+		dbuf := make([]byte, StdEncoding.DecodedLen(len(input)))
+		br := badReader{data: []byte(input), errs: []error{readErr}}
+		decoder := NewDecoder(StdEncoding, &br)
+		n, err := decoder.Read(dbuf)
+		testEqual(t, "Read after EOF, n = %d, expected %d", n, 0)
+		if _, ok := err.(CorruptInputError); !ok {
+			t.Errorf("Corrupt input error expected.  Found %T", err)
+		}
+	}
+}
+
+// TestReaderEOF ensures decoder.Read behaves correctly when input data is
+// exhausted.
+func TestReaderEOF(t *testing.T) {
+	for _, readErr := range []error{io.EOF, nil} {
+		input := "MZXW6YTB"
+		br := badReader{data: []byte(input), errs: []error{nil, readErr}}
+		decoder := NewDecoder(StdEncoding, &br)
+		dbuf := make([]byte, StdEncoding.DecodedLen(len(input)))
+		n, err := decoder.Read(dbuf)
+		testEqual(t, "Decoding of %q err = %v, expected %v", string(input), err, error(nil))
+		n, err = decoder.Read(dbuf)
+		testEqual(t, "Read after EOF, n = %d, expected %d", n, 0)
+		testEqual(t, "Read after EOF, err = %v, expected %v", err, io.EOF)
+		n, err = decoder.Read(dbuf)
+		testEqual(t, "Read after EOF, n = %d, expected %d", n, 0)
+		testEqual(t, "Read after EOF, err = %v, expected %v", err, io.EOF)
+	}
+}
+
 func TestDecoderBuffering(t *testing.T) {
 	for bs := 1; bs <= 12; bs++ {
 		decoder := NewDecoder(StdEncoding, strings.NewReader(bigtest.encoded))
 		buf := make([]byte, len(bigtest.decoded)+12)
 		var total int
-		for total = 0; total < len(bigtest.decoded); {
-			n, err := decoder.Read(buf[total : total+bs])
-			testEqual(t, "Read from %q at pos %d = %d, %v, want _, %v", bigtest.encoded, total, n, err, error(nil))
+		var n int
+		var err error
+		for total = 0; total < len(bigtest.decoded) && err == nil; {
+			n, err = decoder.Read(buf[total : total+bs])
 			total += n
 		}
+		if err != nil && err != io.EOF {
+			t.Errorf("Read from %q at pos %d = %d, unexpected error %v", bigtest.encoded, total, n, err)
+		}
 		testEqual(t, "Decoding/%d of %q = %q, want %q", bs, bigtest.encoded, string(buf[0:total]), bigtest.decoded)
 	}
 }
@@ -300,3 +460,121 @@
 		StdEncoding.DecodeString(data)
 	}
 }
+
+func TestWithCustomPadding(t *testing.T) {
+	for _, testcase := range pairs {
+		defaultPadding := StdEncoding.EncodeToString([]byte(testcase.decoded))
+		customPadding := StdEncoding.WithPadding('@').EncodeToString([]byte(testcase.decoded))
+		expected := strings.Replace(defaultPadding, "=", "@", -1)
+
+		if expected != customPadding {
+			t.Errorf("Expected custom %s, got %s", expected, customPadding)
+		}
+		if testcase.encoded != defaultPadding {
+			t.Errorf("Expected %s, got %s", testcase.encoded, defaultPadding)
+		}
+	}
+}
+
+func TestWithoutPadding(t *testing.T) {
+	for _, testcase := range pairs {
+		defaultPadding := StdEncoding.EncodeToString([]byte(testcase.decoded))
+		customPadding := StdEncoding.WithPadding(NoPadding).EncodeToString([]byte(testcase.decoded))
+		expected := strings.TrimRight(defaultPadding, "=")
+
+		if expected != customPadding {
+			t.Errorf("Expected custom %s, got %s", expected, customPadding)
+		}
+		if testcase.encoded != defaultPadding {
+			t.Errorf("Expected %s, got %s", testcase.encoded, defaultPadding)
+		}
+	}
+}
+
+func TestDecodeWithPadding(t *testing.T) {
+	encodings := []*Encoding{
+		StdEncoding,
+		StdEncoding.WithPadding('-'),
+		StdEncoding.WithPadding(NoPadding),
+	}
+
+	for i, enc := range encodings {
+		for _, pair := range pairs {
+
+			input := pair.decoded
+			encoded := enc.EncodeToString([]byte(input))
+
+			decoded, err := enc.DecodeString(encoded)
+			if err != nil {
+				t.Errorf("DecodeString Error for encoding %d (%q): %v", i, input, err)
+			}
+
+			if input != string(decoded) {
+				t.Errorf("Unexpected result for encoding %d: got %q; want %q", i, decoded, input)
+			}
+		}
+	}
+}
+
+func TestDecodeWithWrongPadding(t *testing.T) {
+	encoded := StdEncoding.EncodeToString([]byte("foobar"))
+
+	_, err := StdEncoding.WithPadding('-').DecodeString(encoded)
+	if err == nil {
+		t.Error("expected error")
+	}
+
+	_, err = StdEncoding.WithPadding(NoPadding).DecodeString(encoded)
+	if err == nil {
+		t.Error("expected error")
+	}
+}
+
+func TestEncodedDecodedLen(t *testing.T) {
+	type test struct {
+		in      int
+		wantEnc int
+		wantDec int
+	}
+	data := bytes.Repeat([]byte("x"), 100)
+	for _, test := range []struct {
+		name  string
+		enc   *Encoding
+		cases []test
+	}{
+		{"StdEncoding", StdEncoding, []test{
+			{0, 0, 0},
+			{1, 8, 5},
+			{5, 8, 5},
+			{6, 16, 10},
+			{10, 16, 10},
+		}},
+		{"NoPadding", StdEncoding.WithPadding(NoPadding), []test{
+			{0, 0, 0},
+			{1, 2, 1},
+			{2, 4, 2},
+			{5, 8, 5},
+			{6, 10, 6},
+			{7, 12, 7},
+			{10, 16, 10},
+			{11, 18, 11},
+		}},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			for _, tc := range test.cases {
+				encLen := test.enc.EncodedLen(tc.in)
+				decLen := test.enc.DecodedLen(encLen)
+				enc := test.enc.EncodeToString(data[:tc.in])
+				if len(enc) != encLen {
+					t.Fatalf("EncodedLen(%d) = %d but encoded to %q (%d)", tc.in, encLen, enc, len(enc))
+				}
+				if encLen != tc.wantEnc {
+					t.Fatalf("EncodedLen(%d) = %d; want %d", tc.in, encLen, tc.wantEnc)
+				}
+				if decLen != tc.wantDec {
+					t.Fatalf("DecodedLen(%d) = %d; want %d", encLen, decLen, tc.wantDec)
+				}
+			}
+		})
+	}
+}
diff --git a/libgo/go/encoding/base64/base64.go b/libgo/go/encoding/base64/base64.go
index d2efad4..b208f9e 100644
--- a/libgo/go/encoding/base64/base64.go
+++ b/libgo/go/encoding/base64/base64.go
@@ -35,13 +35,19 @@
 const encodeURL = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"
 
 // NewEncoding returns a new padded Encoding defined by the given alphabet,
-// which must be a 64-byte string.
+// which must be a 64-byte string that does not contain the padding character
+// or CR / LF ('\r', '\n').
 // The resulting Encoding uses the default padding character ('='),
 // which may be changed or disabled via WithPadding.
 func NewEncoding(encoder string) *Encoding {
 	if len(encoder) != 64 {
 		panic("encoding alphabet is not 64-bytes long")
 	}
+	for i := 0; i < len(encoder); i++ {
+		if encoder[i] == '\n' || encoder[i] == '\r' {
+			panic("encoding alphabet contains newline character")
+		}
+	}
 
 	e := new(Encoding)
 	e.padChar = StdPadding
@@ -58,7 +64,20 @@
 
 // WithPadding creates a new encoding identical to enc except
 // with a specified padding character, or NoPadding to disable padding.
+// The padding character must not be '\r' or '\n', must not
+// be contained in the encoding's alphabet and must be a rune equal or
+// below '\xff'.
 func (enc Encoding) WithPadding(padding rune) *Encoding {
+	if padding == '\r' || padding == '\n' || padding > 0xff {
+		panic("invalid padding")
+	}
+
+	for i := 0; i < len(enc.encode); i++ {
+		if rune(enc.encode[i]) == padding {
+			panic("padding contained in alphabet")
+		}
+	}
+
 	enc.padChar = padding
 	return &enc
 }
@@ -256,19 +275,17 @@
 func (enc *Encoding) decode(dst, src []byte) (n int, end bool, err error) {
 	si := 0
 
-	// skip over newlines
-	for si < len(src) && (src[si] == '\n' || src[si] == '\r') {
-		si++
-	}
-
 	for si < len(src) && !end {
 		// Decode quantum using the base64 alphabet
 		var dbuf [4]byte
 		dinc, dlen := 3, 4
 
-		for j := range dbuf {
+		for j := 0; j < len(dbuf); j++ {
 			if len(src) == si {
-				if enc.padChar != NoPadding || j < 2 {
+				switch {
+				case j == 0:
+					return n, false, nil
+				case j == 1, enc.padChar != NoPadding:
 					return n, false, CorruptInputError(si - j)
 				}
 				dinc, dlen, end = j-1, j, true
@@ -277,11 +294,17 @@
 			in := src[si]
 
 			si++
-			// skip over newlines
-			for si < len(src) && (src[si] == '\n' || src[si] == '\r') {
-				si++
+
+			out := enc.decodeMap[in]
+			if out != 0xFF {
+				dbuf[j] = out
+				continue
 			}
 
+			if in == '\n' || in == '\r' {
+				j--
+				continue
+			}
 			if rune(in) == enc.padChar {
 				// We've reached the end and there's padding
 				switch j {
@@ -290,6 +313,10 @@
 					return n, false, CorruptInputError(si - 1)
 				case 2:
 					// "==" is expected, the first "=" is already consumed.
+					// skip over newlines
+					for si < len(src) && (src[si] == '\n' || src[si] == '\r') {
+						si++
+					}
 					if si == len(src) {
 						// not enough padding
 						return n, false, CorruptInputError(len(src))
@@ -300,10 +327,10 @@
 					}
 
 					si++
-					// skip over newlines
-					for si < len(src) && (src[si] == '\n' || src[si] == '\r') {
-						si++
-					}
+				}
+				// skip over newlines
+				for si < len(src) && (src[si] == '\n' || src[si] == '\r') {
+					si++
 				}
 				if si < len(src) {
 					// trailing garbage
@@ -312,10 +339,7 @@
 				dinc, dlen, end = 3, j, true
 				break
 			}
-			dbuf[j] = enc.decodeMap[in]
-			if dbuf[j] == 0xFF {
-				return n, false, CorruptInputError(si - 1)
-			}
+			return n, false, CorruptInputError(si - 1)
 		}
 
 		// Convert 4x 6bit source bytes into 3 bytes
diff --git a/libgo/go/encoding/base64/base64_test.go b/libgo/go/encoding/base64/base64_test.go
index e2e1d59..05011fb 100644
--- a/libgo/go/encoding/base64/base64_test.go
+++ b/libgo/go/encoding/base64/base64_test.go
@@ -7,6 +7,7 @@
 import (
 	"bytes"
 	"errors"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"reflect"
@@ -63,7 +64,7 @@
 }
 
 // Both URL and unpadding conversions
-func rawUrlRef(ref string) string {
+func rawURLRef(ref string) string {
 	return rawRef(urlRef(ref))
 }
 
@@ -83,12 +84,12 @@
 	{StdEncoding, stdRef},
 	{URLEncoding, urlRef},
 	{RawStdEncoding, rawRef},
-	{RawURLEncoding, rawUrlRef},
+	{RawURLEncoding, rawURLRef},
 	{funnyEncoding, funnyRef},
 	{StdEncoding.Strict(), stdRef},
 	{URLEncoding.Strict(), urlRef},
 	{RawStdEncoding.Strict(), rawRef},
-	{RawURLEncoding.Strict(), rawUrlRef},
+	{RawURLEncoding.Strict(), rawURLRef},
 	{funnyEncoding.Strict(), funnyRef},
 }
 
@@ -98,6 +99,7 @@
 }
 
 func testEqual(t *testing.T, msg string, args ...interface{}) bool {
+	t.Helper()
 	if args[len(args)-2] != args[len(args)-1] {
 		t.Errorf(msg, args...)
 		return false
@@ -187,11 +189,15 @@
 		decoder := NewDecoder(StdEncoding, strings.NewReader(bigtest.encoded))
 		buf := make([]byte, len(bigtest.decoded)+12)
 		var total int
-		for total = 0; total < len(bigtest.decoded); {
-			n, err := decoder.Read(buf[total : total+bs])
-			testEqual(t, "Read from %q at pos %d = %d, %v, want _, %v", bigtest.encoded, total, n, err, error(nil))
+		var n int
+		var err error
+		for total = 0; total < len(bigtest.decoded) && err == nil; {
+			n, err = decoder.Read(buf[total : total+bs])
 			total += n
 		}
+		if err != nil && err != io.EOF {
+			t.Errorf("Read from %q at pos %d = %d, unexpected error %v", bigtest.encoded, total, n, err)
+		}
 		testEqual(t, "Decoding/%d of %q = %q, want %q", bs, bigtest.encoded, string(buf[0:total]), bigtest.decoded)
 	}
 }
@@ -202,6 +208,9 @@
 		offset int // -1 means no corruption.
 	}{
 		{"", -1},
+		{"\n", -1},
+		{"AAA=\n", -1},
+		{"AAAA\n", -1},
 		{"!!!!", 0},
 		{"====", 0},
 		{"x===", 1},
@@ -220,6 +229,8 @@
 		{"AAAA", -1},
 		{"AAAAAA=", 7},
 		{"YWJjZA=====", 8},
+		{"A!\n", 1},
+		{"A=\n", 1},
 	}
 	for _, tc := range testCases {
 		dbuf := make([]byte, StdEncoding.DecodedLen(len(tc.input)))
@@ -466,10 +477,19 @@
 }
 
 func BenchmarkDecodeString(b *testing.B) {
-	data := StdEncoding.EncodeToString(make([]byte, 8192))
-	b.SetBytes(int64(len(data)))
-	for i := 0; i < b.N; i++ {
-		StdEncoding.DecodeString(data)
+	sizes := []int{2, 4, 8, 64, 8192}
+	benchFunc := func(b *testing.B, benchSize int) {
+		data := StdEncoding.EncodeToString(make([]byte, benchSize))
+		b.SetBytes(int64(len(data)))
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			StdEncoding.DecodeString(data)
+		}
+	}
+	for _, size := range sizes {
+		b.Run(fmt.Sprintf("%d", size), func(b *testing.B) {
+			benchFunc(b, size)
+		})
 	}
 }
 
diff --git a/libgo/go/encoding/binary/binary.go b/libgo/go/encoding/binary/binary.go
index 3834254..2d01a3c 100644
--- a/libgo/go/encoding/binary/binary.go
+++ b/libgo/go/encoding/binary/binary.go
@@ -152,7 +152,8 @@
 // When reading into structs, the field data for fields with
 // blank (_) field names is skipped; i.e., blank field names
 // may be used for padding.
-// When reading into a struct, all non-blank fields must be exported.
+// When reading into a struct, all non-blank fields must be exported
+// or Read may panic.
 //
 // The error is EOF only if no bytes were read.
 // If an EOF happens after reading some but not all the bytes,
diff --git a/libgo/go/encoding/binary/binary_test.go b/libgo/go/encoding/binary/binary_test.go
index fc7f276..0547bee 100644
--- a/libgo/go/encoding/binary/binary_test.go
+++ b/libgo/go/encoding/binary/binary_test.go
@@ -500,3 +500,27 @@
 	}
 	b.StopTimer()
 }
+
+func BenchmarkPutUint16(b *testing.B) {
+	buf := [2]byte{}
+	b.SetBytes(2)
+	for i := 0; i < b.N; i++ {
+		BigEndian.PutUint16(buf[:], uint16(i))
+	}
+}
+
+func BenchmarkPutUint32(b *testing.B) {
+	buf := [4]byte{}
+	b.SetBytes(4)
+	for i := 0; i < b.N; i++ {
+		BigEndian.PutUint32(buf[:], uint32(i))
+	}
+}
+
+func BenchmarkPutUint64(b *testing.B) {
+	buf := [8]byte{}
+	b.SetBytes(8)
+	for i := 0; i < b.N; i++ {
+		BigEndian.PutUint64(buf[:], uint64(i))
+	}
+}
diff --git a/libgo/go/encoding/binary/varint.go b/libgo/go/encoding/binary/varint.go
index d7a75f9..bcb8ac9 100644
--- a/libgo/go/encoding/binary/varint.go
+++ b/libgo/go/encoding/binary/varint.go
@@ -53,9 +53,9 @@
 // number of bytes read (> 0). If an error occurred, the value is 0
 // and the number of bytes n is <= 0 meaning:
 //
-//	n == 0: buf too small
-//	n  < 0: value larger than 64 bits (overflow)
-//              and -n is the number of bytes read
+// 	n == 0: buf too small
+// 	n  < 0: value larger than 64 bits (overflow)
+// 	        and -n is the number of bytes read
 //
 func Uvarint(buf []byte) (uint64, int) {
 	var x uint64
@@ -87,9 +87,9 @@
 // number of bytes read (> 0). If an error occurred, the value is 0
 // and the number of bytes n is <= 0 with the following meaning:
 //
-//	n == 0: buf too small
-//	n  < 0: value larger than 64 bits (overflow)
-//              and -n is the number of bytes read
+// 	n == 0: buf too small
+// 	n  < 0: value larger than 64 bits (overflow)
+// 	        and -n is the number of bytes read
 //
 func Varint(buf []byte) (int64, int) {
 	ux, n := Uvarint(buf) // ok to continue in presence of error
diff --git a/libgo/go/encoding/csv/reader.go b/libgo/go/encoding/csv/reader.go
index c8c4ca7..a3497c8 100644
--- a/libgo/go/encoding/csv/reader.go
+++ b/libgo/go/encoding/csv/reader.go
@@ -110,6 +110,10 @@
 	// If TrimLeadingSpace is true, leading white space in a field is ignored.
 	// This is done even if the field delimiter, Comma, is white space.
 	TrimLeadingSpace bool
+	// ReuseRecord controls whether calls to Read may return a slice sharing
+	// the backing array of the previous call's returned slice for performance.
+	// By default, each call to Read returns newly allocated memory owned by the caller.
+	ReuseRecord bool
 
 	line   int
 	column int
@@ -122,6 +126,9 @@
 	// Indexes of fields inside lineBuffer
 	// The i'th field starts at offset fieldIndexes[i] in lineBuffer.
 	fieldIndexes []int
+
+	// only used when ReuseRecord == true
+	lastRecord []string
 }
 
 // NewReader returns a new Reader that reads from r.
@@ -147,9 +154,43 @@
 // Except for that case, Read always returns either a non-nil
 // record or a non-nil error, but not both.
 // If there is no data left to be read, Read returns nil, io.EOF.
+// If ReuseRecord is true, the returned slice may be shared
+// between multiple calls to Read.
 func (r *Reader) Read() (record []string, err error) {
+	if r.ReuseRecord {
+		record, err = r.readRecord(r.lastRecord)
+		r.lastRecord = record
+	} else {
+		record, err = r.readRecord(nil)
+	}
+
+	return record, err
+}
+
+// ReadAll reads all the remaining records from r.
+// Each record is a slice of fields.
+// A successful call returns err == nil, not err == io.EOF. Because ReadAll is
+// defined to read until EOF, it does not treat end of file as an error to be
+// reported.
+func (r *Reader) ReadAll() (records [][]string, err error) {
 	for {
-		record, err = r.parseRecord()
+		record, err := r.readRecord(nil)
+		if err == io.EOF {
+			return records, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		records = append(records, record)
+	}
+}
+
+// readRecord reads and parses a single csv record from r.
+// Unlike parseRecord, readRecord handles FieldsPerRecord.
+// If dst has enough capacity it will be used for the returned record.
+func (r *Reader) readRecord(dst []string) (record []string, err error) {
+	for {
+		record, err = r.parseRecord(dst)
 		if record != nil {
 			break
 		}
@@ -169,24 +210,6 @@
 	return record, nil
 }
 
-// ReadAll reads all the remaining records from r.
-// Each record is a slice of fields.
-// A successful call returns err == nil, not err == io.EOF. Because ReadAll is
-// defined to read until EOF, it does not treat end of file as an error to be
-// reported.
-func (r *Reader) ReadAll() (records [][]string, err error) {
-	for {
-		record, err := r.Read()
-		if err == io.EOF {
-			return records, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		records = append(records, record)
-	}
-}
-
 // readRune reads one rune from r, folding \r\n to \n and keeping track
 // of how far into the line we have read.  r.column will point to the start
 // of this rune, not the end of this rune.
@@ -223,7 +246,8 @@
 }
 
 // parseRecord reads and parses a single csv record from r.
-func (r *Reader) parseRecord() (fields []string, err error) {
+// If dst has enough capacity it will be used for the returned fields.
+func (r *Reader) parseRecord(dst []string) (fields []string, err error) {
 	// Each record starts on a new line. We increment our line
 	// number (lines start at 1, not 0) and set column to -1
 	// so as we increment in readRune it points to the character we read.
@@ -275,7 +299,12 @@
 	// minimal and a tradeoff for better performance through the combined
 	// allocations.
 	line := r.lineBuffer.String()
-	fields = make([]string, fieldCount)
+
+	if cap(dst) >= fieldCount {
+		fields = dst[:fieldCount]
+	} else {
+		fields = make([]string, fieldCount)
+	}
 
 	for i, idx := range r.fieldIndexes {
 		if i == fieldCount-1 {
diff --git a/libgo/go/encoding/csv/reader_test.go b/libgo/go/encoding/csv/reader_test.go
index 7b3aca4..5ab1b61 100644
--- a/libgo/go/encoding/csv/reader_test.go
+++ b/libgo/go/encoding/csv/reader_test.go
@@ -24,6 +24,7 @@
 	LazyQuotes       bool
 	TrailingComma    bool
 	TrimLeadingSpace bool
+	ReuseRecord      bool
 
 	Error  string
 	Line   int // Expected error line if != 0
@@ -260,6 +261,15 @@
 			{"c", "d", "e"},
 		},
 	},
+	{
+		Name:        "ReadAllReuseRecord",
+		ReuseRecord: true,
+		Input:       "a,b\nc,d",
+		Output: [][]string{
+			{"a", "b"},
+			{"c", "d"},
+		},
+	},
 }
 
 func TestRead(t *testing.T) {
@@ -274,6 +284,7 @@
 		r.LazyQuotes = tt.LazyQuotes
 		r.TrailingComma = tt.TrailingComma
 		r.TrimLeadingSpace = tt.TrimLeadingSpace
+		r.ReuseRecord = tt.ReuseRecord
 		if tt.Comma != 0 {
 			r.Comma = tt.Comma
 		}
@@ -369,3 +380,23 @@
 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
 `, 3))
 }
+
+func BenchmarkReadReuseRecord(b *testing.B) {
+	benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true }, benchmarkCSVData)
+}
+
+func BenchmarkReadReuseRecordWithFieldsPerRecord(b *testing.B) {
+	benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true; r.FieldsPerRecord = 4 }, benchmarkCSVData)
+}
+
+func BenchmarkReadReuseRecordWithoutFieldsPerRecord(b *testing.B) {
+	benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true; r.FieldsPerRecord = -1 }, benchmarkCSVData)
+}
+
+func BenchmarkReadReuseRecordLargeFields(b *testing.B) {
+	benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true }, strings.Repeat(`xxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+xxxxxxxxxxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvv
+,,zzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+`, 3))
+}
diff --git a/libgo/go/encoding/gob/codec_test.go b/libgo/go/encoding/gob/codec_test.go
index d4002cb..eb9f306 100644
--- a/libgo/go/encoding/gob/codec_test.go
+++ b/libgo/go/encoding/gob/codec_test.go
@@ -47,7 +47,6 @@
 	if e := recover(); e != nil {
 		t.Error(e.(gobError).err) // Will re-panic if not one of our errors, such as a runtime error.
 	}
-	return
 }
 
 func newDecBuffer(data []byte) *decBuffer {
@@ -321,7 +320,7 @@
 	}
 }
 
-func execDec(typ string, instr *decInstr, state *decoderState, t *testing.T, value reflect.Value) {
+func execDec(instr *decInstr, state *decoderState, t *testing.T, value reflect.Value) {
 	defer testError(t)
 	v := int(state.decodeUint())
 	if v+state.fieldnum != 6 {
@@ -348,7 +347,7 @@
 		var data bool
 		instr := &decInstr{decBool, 6, nil, ovfl}
 		state := newDecodeStateFromData(boolResult)
-		execDec("bool", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != true {
 			t.Errorf("bool a = %v not true", data)
 		}
@@ -358,7 +357,7 @@
 		var data int
 		instr := &decInstr{decOpTable[reflect.Int], 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
-		execDec("int", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("int a = %v not 17", data)
 		}
@@ -369,7 +368,7 @@
 		var data uint
 		instr := &decInstr{decOpTable[reflect.Uint], 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
-		execDec("uint", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("uint a = %v not 17", data)
 		}
@@ -380,7 +379,7 @@
 		var data int8
 		instr := &decInstr{decInt8, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
-		execDec("int8", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("int8 a = %v not 17", data)
 		}
@@ -391,7 +390,7 @@
 		var data uint8
 		instr := &decInstr{decUint8, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
-		execDec("uint8", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("uint8 a = %v not 17", data)
 		}
@@ -402,7 +401,7 @@
 		var data int16
 		instr := &decInstr{decInt16, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
-		execDec("int16", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("int16 a = %v not 17", data)
 		}
@@ -413,7 +412,7 @@
 		var data uint16
 		instr := &decInstr{decUint16, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
-		execDec("uint16", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("uint16 a = %v not 17", data)
 		}
@@ -424,7 +423,7 @@
 		var data int32
 		instr := &decInstr{decInt32, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
-		execDec("int32", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("int32 a = %v not 17", data)
 		}
@@ -435,7 +434,7 @@
 		var data uint32
 		instr := &decInstr{decUint32, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
-		execDec("uint32", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("uint32 a = %v not 17", data)
 		}
@@ -446,7 +445,7 @@
 		var data uintptr
 		instr := &decInstr{decOpTable[reflect.Uintptr], 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
-		execDec("uintptr", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("uintptr a = %v not 17", data)
 		}
@@ -457,7 +456,7 @@
 		var data int64
 		instr := &decInstr{decInt64, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
-		execDec("int64", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("int64 a = %v not 17", data)
 		}
@@ -468,7 +467,7 @@
 		var data uint64
 		instr := &decInstr{decUint64, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
-		execDec("uint64", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("uint64 a = %v not 17", data)
 		}
@@ -479,7 +478,7 @@
 		var data float32
 		instr := &decInstr{decFloat32, 6, nil, ovfl}
 		state := newDecodeStateFromData(floatResult)
-		execDec("float32", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("float32 a = %v not 17", data)
 		}
@@ -490,7 +489,7 @@
 		var data float64
 		instr := &decInstr{decFloat64, 6, nil, ovfl}
 		state := newDecodeStateFromData(floatResult)
-		execDec("float64", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
 			t.Errorf("float64 a = %v not 17", data)
 		}
@@ -501,7 +500,7 @@
 		var data complex64
 		instr := &decInstr{decOpTable[reflect.Complex64], 6, nil, ovfl}
 		state := newDecodeStateFromData(complexResult)
-		execDec("complex", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17+19i {
 			t.Errorf("complex a = %v not 17+19i", data)
 		}
@@ -512,7 +511,7 @@
 		var data complex128
 		instr := &decInstr{decOpTable[reflect.Complex128], 6, nil, ovfl}
 		state := newDecodeStateFromData(complexResult)
-		execDec("complex", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != 17+19i {
 			t.Errorf("complex a = %v not 17+19i", data)
 		}
@@ -523,7 +522,7 @@
 		var data []byte
 		instr := &decInstr{decUint8Slice, 6, nil, ovfl}
 		state := newDecodeStateFromData(bytesResult)
-		execDec("bytes", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if string(data) != "hello" {
 			t.Errorf(`bytes a = %q not "hello"`, string(data))
 		}
@@ -534,7 +533,7 @@
 		var data string
 		instr := &decInstr{decString, 6, nil, ovfl}
 		state := newDecodeStateFromData(bytesResult)
-		execDec("bytes", instr, state, t, reflect.ValueOf(&data))
+		execDec(instr, state, t, reflect.ValueOf(&data))
 		if data != "hello" {
 			t.Errorf(`bytes a = %q not "hello"`, data)
 		}
@@ -545,11 +544,18 @@
 	type T2 struct {
 		T string
 	}
-	s1 := "string1"
-	s2 := "string2"
+	type T3 struct {
+		X float64
+		Z *int
+	}
 	type T1 struct {
 		A, B, C  int
 		M        map[string]*float64
+		M2       map[int]T3
+		Mstring  map[string]string
+		Mintptr  map[int]*int
+		Mcomp    map[complex128]complex128
+		Marr     map[[2]string][2]*float64
 		EmptyMap map[string]int // to check that we receive a non-nil map.
 		N        *[3]float64
 		Strs     *[2]string
@@ -561,11 +567,35 @@
 	}
 	pi := 3.14159
 	e := 2.71828
+	two := 2.0
+	meaning := 42
+	fingers := 5
+	s1 := "string1"
+	s2 := "string2"
+	var comp1 complex128 = complex(1.0, 1.0)
+	var comp2 complex128 = complex(1.0, 1.0)
+	var arr1 [2]string
+	arr1[0] = s1
+	arr1[1] = s2
+	var arr2 [2]string
+	arr2[0] = s2
+	arr2[1] = s1
+	var floatArr1 [2]*float64
+	floatArr1[0] = &pi
+	floatArr1[1] = &e
+	var floatArr2 [2]*float64
+	floatArr2[0] = &e
+	floatArr2[1] = &two
 	t1 := &T1{
 		A:        17,
 		B:        18,
 		C:        -5,
 		M:        map[string]*float64{"pi": &pi, "e": &e},
+		M2:       map[int]T3{4: T3{X: pi, Z: &meaning}, 10: T3{X: e, Z: &fingers}},
+		Mstring:  map[string]string{"pi": "3.14", "e": "2.71"},
+		Mintptr:  map[int]*int{meaning: &fingers, fingers: &meaning},
+		Mcomp:    map[complex128]complex128{comp1: comp2, comp2: comp1},
+		Marr:     map[[2]string][2]*float64{arr1: floatArr1, arr2: floatArr2},
 		EmptyMap: make(map[string]int),
 		N:        &[3]float64{1.5, 2.5, 3.5},
 		Strs:     &[2]string{s1, s2},
diff --git a/libgo/go/encoding/gob/decode.go b/libgo/go/encoding/gob/decode.go
index 9645dc5..8dece42 100644
--- a/libgo/go/encoding/gob/decode.go
+++ b/libgo/go/encoding/gob/decode.go
@@ -11,6 +11,7 @@
 	"errors"
 	"io"
 	"math"
+	"math/bits"
 	"reflect"
 )
 
@@ -313,12 +314,7 @@
 // (for example) transmit more compactly. This routine does the
 // unswizzling.
 func float64FromBits(u uint64) float64 {
-	var v uint64
-	for i := 0; i < 8; i++ {
-		v <<= 8
-		v |= u & 0xFF
-		u >>= 8
-	}
+	v := bits.ReverseBytes64(u)
 	return math.Float64frombits(v)
 }
 
@@ -430,7 +426,7 @@
 // decodeSingle decodes a top-level value that is not a struct and stores it in value.
 // Such values are preceded by a zero, making them have the memory layout of a
 // struct field (although with an illegal field number).
-func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, value reflect.Value) {
+func (dec *Decoder) decodeSingle(engine *decEngine, value reflect.Value) {
 	state := dec.newDecoderState(&dec.buf)
 	defer dec.freeDecoderState(state)
 	state.fieldnum = singletonField
@@ -446,7 +442,7 @@
 // differ from ut.indir, which was computed when the engine was built.
 // This state cannot arise for decodeSingle, which is called directly
 // from the user's value, not from the innards of an engine.
-func (dec *Decoder) decodeStruct(engine *decEngine, ut *userTypeInfo, value reflect.Value) {
+func (dec *Decoder) decodeStruct(engine *decEngine, value reflect.Value) {
 	state := dec.newDecoderState(&dec.buf)
 	defer dec.freeDecoderState(state)
 	state.fieldnum = -1
@@ -538,7 +534,7 @@
 // decodeArray decodes an array and stores it in value.
 // The length is an unsigned integer preceding the elements. Even though the length is redundant
 // (it's part of the type), it's a useful check and is included in the encoding.
-func (dec *Decoder) decodeArray(atyp reflect.Type, state *decoderState, value reflect.Value, elemOp decOp, length int, ovfl error, helper decHelper) {
+func (dec *Decoder) decodeArray(state *decoderState, value reflect.Value, elemOp decOp, length int, ovfl error, helper decHelper) {
 	if n := state.decodeUint(); n != uint64(length) {
 		errorf("length mismatch in decodeArray")
 	}
@@ -546,12 +542,12 @@
 }
 
 // decodeIntoValue is a helper for map decoding.
-func decodeIntoValue(state *decoderState, op decOp, isPtr bool, value reflect.Value, ovfl error) reflect.Value {
-	instr := &decInstr{op, 0, nil, ovfl}
+func decodeIntoValue(state *decoderState, op decOp, isPtr bool, value reflect.Value, instr *decInstr) reflect.Value {
 	v := value
 	if isPtr {
 		v = decAlloc(value)
 	}
+
 	op(instr, state, v)
 	return value
 }
@@ -561,17 +557,24 @@
 // Because the internals of maps are not visible to us, we must
 // use reflection rather than pointer magic.
 func (dec *Decoder) decodeMap(mtyp reflect.Type, state *decoderState, value reflect.Value, keyOp, elemOp decOp, ovfl error) {
-	if value.IsNil() {
-		// Allocate map.
-		value.Set(reflect.MakeMap(mtyp))
-	}
 	n := int(state.decodeUint())
+	if value.IsNil() {
+		value.Set(reflect.MakeMapWithSize(mtyp, n))
+	}
 	keyIsPtr := mtyp.Key().Kind() == reflect.Ptr
 	elemIsPtr := mtyp.Elem().Kind() == reflect.Ptr
+	keyInstr := &decInstr{keyOp, 0, nil, ovfl}
+	elemInstr := &decInstr{elemOp, 0, nil, ovfl}
+	keyP := reflect.New(mtyp.Key())
+	keyZ := reflect.Zero(mtyp.Key())
+	elemP := reflect.New(mtyp.Elem())
+	elemZ := reflect.Zero(mtyp.Elem())
 	for i := 0; i < n; i++ {
-		key := decodeIntoValue(state, keyOp, keyIsPtr, allocValue(mtyp.Key()), ovfl)
-		elem := decodeIntoValue(state, elemOp, elemIsPtr, allocValue(mtyp.Elem()), ovfl)
+		key := decodeIntoValue(state, keyOp, keyIsPtr, keyP.Elem(), keyInstr)
+		elem := decodeIntoValue(state, elemOp, elemIsPtr, elemP.Elem(), elemInstr)
 		value.SetMapIndex(key, elem)
+		keyP.Elem().Set(keyZ)
+		elemP.Elem().Set(elemZ)
 	}
 }
 
@@ -657,12 +660,12 @@
 		errorf("name too long (%d bytes): %.20q...", len(name), name)
 	}
 	// The concrete type must be registered.
-	registerLock.RLock()
-	typ, ok := nameToConcreteType[string(name)]
-	registerLock.RUnlock()
+	typi, ok := nameToConcreteType.Load(string(name))
 	if !ok {
 		errorf("name not registered for interface: %q", name)
 	}
+	typ := typi.(reflect.Type)
+
 	// Read the type id of the concrete value.
 	concreteId := dec.decodeTypeSequence(true)
 	if concreteId < 0 {
@@ -813,7 +816,7 @@
 			ovfl := overflow(name)
 			helper := decArrayHelper[t.Elem().Kind()]
 			op = func(i *decInstr, state *decoderState, value reflect.Value) {
-				state.dec.decodeArray(t, state, value, *elemOp, t.Len(), ovfl, helper)
+				state.dec.decodeArray(state, value, *elemOp, t.Len(), ovfl, helper)
 			}
 
 		case reflect.Map:
@@ -854,7 +857,7 @@
 			}
 			op = func(i *decInstr, state *decoderState, value reflect.Value) {
 				// indirect through enginePtr to delay evaluation for recursive structs.
-				dec.decodeStruct(*enginePtr, ut, value)
+				dec.decodeStruct(*enginePtr, value)
 			}
 		case reflect.Interface:
 			op = func(i *decInstr, state *decoderState, value reflect.Value) {
@@ -1197,9 +1200,9 @@
 			name := base.Name()
 			errorf("type mismatch: no fields matched compiling decoder for %s", name)
 		}
-		dec.decodeStruct(engine, ut, value)
+		dec.decodeStruct(engine, value)
 	} else {
-		dec.decodeSingle(engine, ut, value)
+		dec.decodeSingle(engine, value)
 	}
 }
 
diff --git a/libgo/go/encoding/gob/decoder.go b/libgo/go/encoding/gob/decoder.go
index c182941..8e0b1dd 100644
--- a/libgo/go/encoding/gob/decoder.go
+++ b/libgo/go/encoding/gob/decoder.go
@@ -19,6 +19,10 @@
 
 // A Decoder manages the receipt of type and data information read from the
 // remote side of a connection.
+//
+// The Decoder does only basic sanity checking on decoded input sizes,
+// and its limits are not configurable. Take caution when decoding gob data
+// from untrusted sources.
 type Decoder struct {
 	mutex        sync.Mutex                              // each item must be received atomically
 	r            io.Reader                               // source of the data
diff --git a/libgo/go/encoding/gob/doc.go b/libgo/go/encoding/gob/doc.go
index 1536574..db734ec 100644
--- a/libgo/go/encoding/gob/doc.go
+++ b/libgo/go/encoding/gob/doc.go
@@ -4,7 +4,7 @@
 
 /*
 Package gob manages streams of gobs - binary values exchanged between an
-Encoder (transmitter) and a Decoder (receiver).  A typical use is transporting
+Encoder (transmitter) and a Decoder (receiver). A typical use is transporting
 arguments and results of remote procedure calls (RPCs) such as those provided by
 package "net/rpc".
 
@@ -14,28 +14,28 @@
 
 Basics
 
-A stream of gobs is self-describing.  Each data item in the stream is preceded by
+A stream of gobs is self-describing. Each data item in the stream is preceded by
 a specification of its type, expressed in terms of a small set of predefined
-types.  Pointers are not transmitted, but the things they point to are
+types. Pointers are not transmitted, but the things they point to are
 transmitted; that is, the values are flattened. Nil pointers are not permitted,
 as they have no value. Recursive types work fine, but
-recursive values (data with cycles) are problematic.  This may change.
+recursive values (data with cycles) are problematic. This may change.
 
 To use gobs, create an Encoder and present it with a series of data items as
-values or addresses that can be dereferenced to values.  The Encoder makes sure
-all type information is sent before it is needed.  At the receive side, a
+values or addresses that can be dereferenced to values. The Encoder makes sure
+all type information is sent before it is needed. At the receive side, a
 Decoder retrieves values from the encoded stream and unpacks them into local
 variables.
 
 Types and Values
 
-The source and destination values/types need not correspond exactly.  For structs,
+The source and destination values/types need not correspond exactly. For structs,
 fields (identified by name) that are in the source but absent from the receiving
-variable will be ignored.  Fields that are in the receiving variable but missing
-from the transmitted type or value will be ignored in the destination.  If a field
+variable will be ignored. Fields that are in the receiving variable but missing
+from the transmitted type or value will be ignored in the destination. If a field
 with the same name is present in both, their types must be compatible. Both the
 receiver and transmitter will do all necessary indirection and dereferencing to
-convert between gobs and actual Go values.  For instance, a gob type that is
+convert between gobs and actual Go values. For instance, a gob type that is
 schematically,
 
 	struct { A, B int }
@@ -63,8 +63,8 @@
 	struct { C, D int }		// no field names in common
 
 Integers are transmitted two ways: arbitrary precision signed integers or
-arbitrary precision unsigned integers.  There is no int8, int16 etc.
-discrimination in the gob format; there are only signed and unsigned integers.  As
+arbitrary precision unsigned integers. There is no int8, int16 etc.
+discrimination in the gob format; there are only signed and unsigned integers. As
 described below, the transmitter sends the value in a variable-length encoding;
 the receiver accepts the value and stores it in the destination variable.
 Floating-point numbers are always sent using IEEE-754 64-bit precision (see
@@ -72,7 +72,7 @@
 
 Signed integers may be received into any signed integer variable: int, int16, etc.;
 unsigned integers may be received into any unsigned integer variable; and floating
-point values may be received into any floating point variable.  However,
+point values may be received into any floating point variable. However,
 the destination variable must be able to represent the value or the decode
 operation will fail.
 
@@ -106,17 +106,17 @@
 This section documents the encoding, details that are not important for most
 users. Details are presented bottom-up.
 
-An unsigned integer is sent one of two ways.  If it is less than 128, it is sent
-as a byte with that value.  Otherwise it is sent as a minimal-length big-endian
+An unsigned integer is sent one of two ways. If it is less than 128, it is sent
+as a byte with that value. Otherwise it is sent as a minimal-length big-endian
 (high byte first) byte stream holding the value, preceded by one byte holding the
-byte count, negated.  Thus 0 is transmitted as (00), 7 is transmitted as (07) and
+byte count, negated. Thus 0 is transmitted as (00), 7 is transmitted as (07) and
 256 is transmitted as (FE 01 00).
 
 A boolean is encoded within an unsigned integer: 0 for false, 1 for true.
 
-A signed integer, i, is encoded within an unsigned integer, u.  Within u, bits 1
+A signed integer, i, is encoded within an unsigned integer, u. Within u, bits 1
 upward contain the value; bit 0 says whether they should be complemented upon
-receipt.  The encode algorithm looks like this:
+receipt. The encode algorithm looks like this:
 
 	var u uint
 	if i < 0 {
@@ -127,14 +127,14 @@
 	encodeUnsigned(u)
 
 The low bit is therefore analogous to a sign bit, but making it the complement bit
-instead guarantees that the largest negative integer is not a special case.  For
+instead guarantees that the largest negative integer is not a special case. For
 example, -129=^128=(^256>>1) encodes as (FE 01 01).
 
 Floating-point numbers are always sent as a representation of a float64 value.
-That value is converted to a uint64 using math.Float64bits.  The uint64 is then
-byte-reversed and sent as a regular unsigned integer.  The byte-reversal means the
-exponent and high-precision part of the mantissa go first.  Since the low bits are
-often zero, this can save encoding bytes.  For instance, 17.0 is encoded in only
+That value is converted to a uint64 using math.Float64bits. The uint64 is then
+byte-reversed and sent as a regular unsigned integer. The byte-reversal means the
+exponent and high-precision part of the mantissa go first. Since the low bits are
+often zero, this can save encoding bytes. For instance, 17.0 is encoded in only
 three bytes (FE 31 40).
 
 Strings and slices of bytes are sent as an unsigned count followed by that many
@@ -151,33 +151,39 @@
 In slices and arrays, as well as maps, all elements, even zero-valued elements,
 are transmitted, even if all the elements are zero.
 
-Structs are sent as a sequence of (field number, field value) pairs.  The field
-value is sent using the standard gob encoding for its type, recursively.  If a
+Structs are sent as a sequence of (field number, field value) pairs. The field
+value is sent using the standard gob encoding for its type, recursively. If a
 field has the zero value for its type (except for arrays; see above), it is omitted
-from the transmission.  The field number is defined by the type of the encoded
+from the transmission. The field number is defined by the type of the encoded
 struct: the first field of the encoded type is field 0, the second is field 1,
-etc.  When encoding a value, the field numbers are delta encoded for efficiency
+etc. When encoding a value, the field numbers are delta encoded for efficiency
 and the fields are always sent in order of increasing field number; the deltas are
-therefore unsigned.  The initialization for the delta encoding sets the field
+therefore unsigned. The initialization for the delta encoding sets the field
 number to -1, so an unsigned integer field 0 with value 7 is transmitted as unsigned
-delta = 1, unsigned value = 7 or (01 07).  Finally, after all the fields have been
-sent a terminating mark denotes the end of the struct.  That mark is a delta=0
+delta = 1, unsigned value = 7 or (01 07). Finally, after all the fields have been
+sent a terminating mark denotes the end of the struct. That mark is a delta=0
 value, which has representation (00).
 
 Interface types are not checked for compatibility; all interface types are
 treated, for transmission, as members of a single "interface" type, analogous to
-int or []byte - in effect they're all treated as interface{}.  Interface values
+int or []byte - in effect they're all treated as interface{}. Interface values
 are transmitted as a string identifying the concrete type being sent (a name
 that must be pre-defined by calling Register), followed by a byte count of the
 length of the following data (so the value can be skipped if it cannot be
 stored), followed by the usual encoding of concrete (dynamic) value stored in
-the interface value.  (A nil interface value is identified by the empty string
+the interface value. (A nil interface value is identified by the empty string
 and transmits no value.) Upon receipt, the decoder verifies that the unpacked
 concrete item satisfies the interface of the receiving variable.
 
-The representation of types is described below.  When a type is defined on a given
+If a value is passed to Encode and the type is not a struct (or pointer to struct,
+etc.), for simplicity of processing it is represented as a struct of one field.
+The only visible effect of this is to encode a zero byte after the value, just as
+after the last field of an encoded struct, so that the decode algorithm knows when
+the top-level value is complete.
+
+The representation of types is described below. When a type is defined on a given
 connection between an Encoder and Decoder, it is assigned a signed integer type
-id.  When Encoder.Encode(v) is called, it makes sure there is an id assigned for
+id. When Encoder.Encode(v) is called, it makes sure there is an id assigned for
 the type of v and all its elements and then it sends the pair (typeid, encoded-v)
 where typeid is the type id of the encoded type of v and encoded-v is the gob
 encoding of the value v.
@@ -223,7 +229,7 @@
 before the top-level type id is used to describe an encoded-v.
 
 For simplicity in setup, the connection is defined to understand these types a
-priori, as well as the basic gob types int, uint, etc.  Their ids are:
+priori, as well as the basic gob types int, uint, etc. Their ids are:
 
 	bool        1
 	int         2
@@ -244,7 +250,7 @@
 	MapType     23
 
 Finally, each message created by a call to Encode is preceded by an encoded
-unsigned integer count of the number of bytes remaining in the message.  After
+unsigned integer count of the number of bytes remaining in the message. After
 the initial type name, interface values are wrapped the same way; in effect, the
 interface value acts like a recursive invocation of Encode.
 
@@ -256,7 +262,7 @@
 be predefined or be defined before the value in the stream.
 
 Compatibility: Any future changes to the package will endeavor to maintain
-compatibility with streams encoded using previous versions.  That is, any released
+compatibility with streams encoded using previous versions. That is, any released
 version of this package should be able to decode data written with any previously
 released version, subject to issues such as security fixes. See the Go compatibility
 document for background: https://golang.org/doc/go1compat
@@ -315,7 +321,7 @@
 */
 
 /*
-For implementers and the curious, here is an encoded example.  Given
+For implementers and the curious, here is an encoded example. Given
 	type Point struct {X, Y int}
 and the value
 	p := Point{22, 33}
@@ -326,14 +332,14 @@
 They are determined as follows.
 
 Since this is the first transmission of type Point, the type descriptor
-for Point itself must be sent before the value.  This is the first type
+for Point itself must be sent before the value. This is the first type
 we've sent on this Encoder, so it has type id 65 (0 through 64 are
 reserved).
 
 	1f	// This item (a type descriptor) is 31 bytes long.
 	ff 81	// The negative of the id for the type we're defining, -65.
 		// This is one byte (indicated by FF = -1) followed by
-		// ^-65<<1 | 1.  The low 1 bit signals to complement the
+		// ^-65<<1 | 1. The low 1 bit signals to complement the
 		// rest upon receipt.
 
 	// Now we send a type descriptor, which is itself a struct (wireType).
@@ -370,7 +376,7 @@
 	00	// end of wireType.structType structure
 	00	// end of wireType structure
 
-Now we can send the Point value.  Again the field number resets to -1:
+Now we can send the Point value. Again the field number resets to -1:
 
 	07	// this value is 7 bytes long
 	ff 82	// the type number, 65 (1 byte (-FF) followed by 65<<1)
@@ -387,7 +393,7 @@
 	07 ff 82 01 2c 01 42 00
 
 A single non-struct value at top level is transmitted like a field with
-delta tag 0.  For instance, a signed integer with value 3 presented as
+delta tag 0. For instance, a signed integer with value 3 presented as
 the argument to Encode will emit:
 
 	03 04 00 06
diff --git a/libgo/go/encoding/gob/encode.go b/libgo/go/encoding/gob/encode.go
index 50cd6ad..5371e72 100644
--- a/libgo/go/encoding/gob/encode.go
+++ b/libgo/go/encoding/gob/encode.go
@@ -8,7 +8,9 @@
 
 import (
 	"encoding"
+	"encoding/binary"
 	"math"
+	"math/bits"
 	"reflect"
 	"sync"
 )
@@ -107,14 +109,12 @@
 		state.b.WriteByte(uint8(x))
 		return
 	}
-	i := uint64Size
-	for x > 0 {
-		state.buf[i] = uint8(x)
-		x >>= 8
-		i--
-	}
-	state.buf[i] = uint8(i - uint64Size) // = loop count, negated
-	state.b.Write(state.buf[i : uint64Size+1])
+
+	binary.BigEndian.PutUint64(state.buf[1:], x)
+	bc := bits.LeadingZeros64(x) >> 3      // 8 - bytelen(x)
+	state.buf[bc] = uint8(bc - uint64Size) // and then we subtract 8 to get -bytelen(x)
+
+	state.b.Write(state.buf[bc : uint64Size+1])
 }
 
 // encodeInt writes an encoded signed integer to state.w.
@@ -209,13 +209,7 @@
 // swizzling.
 func floatBits(f float64) uint64 {
 	u := math.Float64bits(f)
-	var v uint64
-	for i := 0; i < 8; i++ {
-		v <<= 8
-		v |= u & 0xFF
-		u >>= 8
-	}
-	return v
+	return bits.ReverseBytes64(u)
 }
 
 // encFloat encodes the floating point value (float32 float64) referenced by v.
@@ -404,12 +398,12 @@
 	}
 
 	ut := userType(iv.Elem().Type())
-	registerLock.RLock()
-	name, ok := concreteTypeToName[ut.base]
-	registerLock.RUnlock()
+	namei, ok := concreteTypeToName.Load(ut.base)
 	if !ok {
 		errorf("type not registered for interface: %s", ut.base)
 	}
+	name := namei.(string)
+
 	// Send the name.
 	state.encodeUint(uint64(len(name)))
 	state.b.WriteString(name)
diff --git a/libgo/go/encoding/gob/encoder_test.go b/libgo/go/encoding/gob/encoder_test.go
index 9256848..a1ca252 100644
--- a/libgo/go/encoding/gob/encoder_test.go
+++ b/libgo/go/encoding/gob/encoder_test.go
@@ -55,6 +55,71 @@
 	}
 }
 
+func TestEncodeIntSlice(t *testing.T) {
+
+	s8 := []int8{1, 5, 12, 22, 35, 51, 70, 92, 117}
+	s16 := []int16{145, 176, 210, 247, 287, 330, 376, 425, 477}
+	s32 := []int32{532, 590, 651, 715, 782, 852, 925, 1001, 1080}
+	s64 := []int64{1162, 1247, 1335, 1426, 1520, 1617, 1717, 1820, 1926}
+
+	t.Run("int8", func(t *testing.T) {
+		var sink bytes.Buffer
+		enc := NewEncoder(&sink)
+		enc.Encode(s8)
+
+		dec := NewDecoder(&sink)
+		res := make([]int8, 9)
+		dec.Decode(&res)
+
+		if !reflect.DeepEqual(s8, res) {
+			t.Fatalf("EncodeIntSlice: expected %v, got %v", s8, res)
+		}
+	})
+
+	t.Run("int16", func(t *testing.T) {
+		var sink bytes.Buffer
+		enc := NewEncoder(&sink)
+		enc.Encode(s16)
+
+		dec := NewDecoder(&sink)
+		res := make([]int16, 9)
+		dec.Decode(&res)
+
+		if !reflect.DeepEqual(s16, res) {
+			t.Fatalf("EncodeIntSlice: expected %v, got %v", s16, res)
+		}
+	})
+
+	t.Run("int32", func(t *testing.T) {
+		var sink bytes.Buffer
+		enc := NewEncoder(&sink)
+		enc.Encode(s32)
+
+		dec := NewDecoder(&sink)
+		res := make([]int32, 9)
+		dec.Decode(&res)
+
+		if !reflect.DeepEqual(s32, res) {
+			t.Fatalf("EncodeIntSlice: expected %v, got %v", s32, res)
+		}
+	})
+
+	t.Run("int64", func(t *testing.T) {
+		var sink bytes.Buffer
+		enc := NewEncoder(&sink)
+		enc.Encode(s64)
+
+		dec := NewDecoder(&sink)
+		res := make([]int64, 9)
+		dec.Decode(&res)
+
+		if !reflect.DeepEqual(s64, res) {
+			t.Fatalf("EncodeIntSlice: expected %v, got %v", s64, res)
+		}
+	})
+
+}
+
 type ET0 struct {
 	A int
 	B string
diff --git a/libgo/go/encoding/gob/error.go b/libgo/go/encoding/gob/error.go
index 8b5265c..949333b 100644
--- a/libgo/go/encoding/gob/error.go
+++ b/libgo/go/encoding/gob/error.go
@@ -39,5 +39,4 @@
 		}
 		*err = ge.err
 	}
-	return
 }
diff --git a/libgo/go/encoding/gob/gobencdec_test.go b/libgo/go/encoding/gob/gobencdec_test.go
index ecc91ee..41a06b26 100644
--- a/libgo/go/encoding/gob/gobencdec_test.go
+++ b/libgo/go/encoding/gob/gobencdec_test.go
@@ -746,7 +746,7 @@
 }
 
 func TestGobEncodeIsZero(t *testing.T) {
-	x := isZeroBug{time.Now(), "hello", -55, isZeroBugArray{1, 2}, isZeroBugInterface{}}
+	x := isZeroBug{time.Unix(1e9, 0), "hello", -55, isZeroBugArray{1, 2}, isZeroBugInterface{}}
 	b := new(bytes.Buffer)
 	enc := NewEncoder(b)
 	err := enc.Encode(x)
diff --git a/libgo/go/encoding/gob/timing_test.go b/libgo/go/encoding/gob/timing_test.go
index 424b7e6..3478bd2 100644
--- a/libgo/go/encoding/gob/timing_test.go
+++ b/libgo/go/encoding/gob/timing_test.go
@@ -8,6 +8,7 @@
 	"bytes"
 	"io"
 	"os"
+	"reflect"
 	"runtime"
 	"testing"
 )
@@ -132,89 +133,60 @@
 	}
 }
 
+func benchmarkEncodeSlice(b *testing.B, a interface{}) {
+	b.ResetTimer()
+	b.RunParallel(func(pb *testing.PB) {
+		var buf bytes.Buffer
+		enc := NewEncoder(&buf)
+
+		for pb.Next() {
+			buf.Reset()
+			err := enc.Encode(a)
+			if err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+}
+
 func BenchmarkEncodeComplex128Slice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]complex128, 1000)
 	for i := range a {
 		a[i] = 1.2 + 3.4i
 	}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		buf.Reset()
-		err := enc.Encode(a)
-		if err != nil {
-			b.Fatal(err)
-		}
-	}
+	benchmarkEncodeSlice(b, a)
 }
 
 func BenchmarkEncodeFloat64Slice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]float64, 1000)
 	for i := range a {
 		a[i] = 1.23e4
 	}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		buf.Reset()
-		err := enc.Encode(a)
-		if err != nil {
-			b.Fatal(err)
-		}
-	}
+	benchmarkEncodeSlice(b, a)
 }
 
 func BenchmarkEncodeInt32Slice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]int32, 1000)
 	for i := range a {
-		a[i] = 1234
+		a[i] = int32(i * 100)
 	}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		buf.Reset()
-		err := enc.Encode(a)
-		if err != nil {
-			b.Fatal(err)
-		}
-	}
+	benchmarkEncodeSlice(b, a)
 }
 
 func BenchmarkEncodeStringSlice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]string, 1000)
 	for i := range a {
 		a[i] = "now is the time"
 	}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		buf.Reset()
-		err := enc.Encode(a)
-		if err != nil {
-			b.Fatal(err)
-		}
-	}
+	benchmarkEncodeSlice(b, a)
 }
 
 func BenchmarkEncodeInterfaceSlice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]interface{}, 1000)
 	for i := range a {
 		a[i] = "now is the time"
 	}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		buf.Reset()
-		err := enc.Encode(a)
-		if err != nil {
-			b.Fatal(err)
-		}
-	}
+	benchmarkEncodeSlice(b, a)
 }
 
 // benchmarkBuf is a read buffer we can reset
@@ -245,120 +217,96 @@
 	b.offset = 0
 }
 
-func BenchmarkDecodeComplex128Slice(b *testing.B) {
+func benchmarkDecodeSlice(b *testing.B, a interface{}) {
 	var buf bytes.Buffer
 	enc := NewEncoder(&buf)
+	err := enc.Encode(a)
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	ra := reflect.ValueOf(a)
+	rt := ra.Type()
+	b.ResetTimer()
+
+	b.RunParallel(func(pb *testing.PB) {
+		// TODO(#19025): Move per-thread allocation before ResetTimer.
+		rp := reflect.New(rt)
+		rp.Elem().Set(reflect.MakeSlice(rt, ra.Len(), ra.Cap()))
+		p := rp.Interface()
+
+		bbuf := benchmarkBuf{data: buf.Bytes()}
+
+		for pb.Next() {
+			bbuf.reset()
+			dec := NewDecoder(&bbuf)
+			err := dec.Decode(p)
+			if err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+}
+
+func BenchmarkDecodeComplex128Slice(b *testing.B) {
 	a := make([]complex128, 1000)
 	for i := range a {
 		a[i] = 1.2 + 3.4i
 	}
-	err := enc.Encode(a)
-	if err != nil {
-		b.Fatal(err)
-	}
-	x := make([]complex128, 1000)
-	bbuf := benchmarkBuf{data: buf.Bytes()}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		bbuf.reset()
-		dec := NewDecoder(&bbuf)
-		err := dec.Decode(&x)
-		if err != nil {
-			b.Fatal(i, err)
-		}
-	}
+	benchmarkDecodeSlice(b, a)
 }
 
 func BenchmarkDecodeFloat64Slice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]float64, 1000)
 	for i := range a {
 		a[i] = 1.23e4
 	}
-	err := enc.Encode(a)
-	if err != nil {
-		b.Fatal(err)
-	}
-	x := make([]float64, 1000)
-	bbuf := benchmarkBuf{data: buf.Bytes()}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		bbuf.reset()
-		dec := NewDecoder(&bbuf)
-		err := dec.Decode(&x)
-		if err != nil {
-			b.Fatal(i, err)
-		}
-	}
+	benchmarkDecodeSlice(b, a)
 }
 
 func BenchmarkDecodeInt32Slice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]int32, 1000)
 	for i := range a {
 		a[i] = 1234
 	}
-	err := enc.Encode(a)
-	if err != nil {
-		b.Fatal(err)
-	}
-	x := make([]int32, 1000)
-	bbuf := benchmarkBuf{data: buf.Bytes()}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		bbuf.reset()
-		dec := NewDecoder(&bbuf)
-		err := dec.Decode(&x)
-		if err != nil {
-			b.Fatal(i, err)
-		}
-	}
+	benchmarkDecodeSlice(b, a)
 }
 
 func BenchmarkDecodeStringSlice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]string, 1000)
 	for i := range a {
 		a[i] = "now is the time"
 	}
-	err := enc.Encode(a)
-	if err != nil {
-		b.Fatal(err)
-	}
-	x := make([]string, 1000)
-	bbuf := benchmarkBuf{data: buf.Bytes()}
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		bbuf.reset()
-		dec := NewDecoder(&bbuf)
-		err := dec.Decode(&x)
-		if err != nil {
-			b.Fatal(i, err)
-		}
-	}
+	benchmarkDecodeSlice(b, a)
 }
 
 func BenchmarkDecodeInterfaceSlice(b *testing.B) {
-	var buf bytes.Buffer
-	enc := NewEncoder(&buf)
 	a := make([]interface{}, 1000)
 	for i := range a {
 		a[i] = "now is the time"
 	}
-	err := enc.Encode(a)
+	benchmarkDecodeSlice(b, a)
+}
+
+func BenchmarkDecodeMap(b *testing.B) {
+	count := 1000
+	m := make(map[int]int, count)
+	for i := 0; i < count; i++ {
+		m[i] = i
+	}
+	var buf bytes.Buffer
+	enc := NewEncoder(&buf)
+	err := enc.Encode(m)
 	if err != nil {
 		b.Fatal(err)
 	}
-	x := make([]interface{}, 1000)
 	bbuf := benchmarkBuf{data: buf.Bytes()}
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
+		var rm map[int]int
 		bbuf.reset()
 		dec := NewDecoder(&bbuf)
-		err := dec.Decode(&x)
+		err := dec.Decode(&rm)
 		if err != nil {
 			b.Fatal(i, err)
 		}
diff --git a/libgo/go/encoding/gob/type.go b/libgo/go/encoding/gob/type.go
index c27f7e9..31c0ef7 100644
--- a/libgo/go/encoding/gob/type.go
+++ b/libgo/go/encoding/gob/type.go
@@ -36,31 +36,21 @@
 	xText              // encoding.TextMarshaler or encoding.TextUnmarshaler
 )
 
-var (
-	// Protected by an RWMutex because we read it a lot and write
-	// it only when we see a new type, typically when compiling.
-	userTypeLock  sync.RWMutex
-	userTypeCache = make(map[reflect.Type]*userTypeInfo)
-)
+var userTypeCache sync.Map // map[reflect.Type]*userTypeInfo
 
 // validType returns, and saves, the information associated with user-provided type rt.
 // If the user type is not valid, err will be non-nil. To be used when the error handler
 // is not set up.
-func validUserType(rt reflect.Type) (ut *userTypeInfo, err error) {
-	userTypeLock.RLock()
-	ut = userTypeCache[rt]
-	userTypeLock.RUnlock()
-	if ut != nil {
-		return
+func validUserType(rt reflect.Type) (*userTypeInfo, error) {
+	if ui, ok := userTypeCache.Load(rt); ok {
+		return ui.(*userTypeInfo), nil
 	}
-	// Now set the value under the write lock.
-	userTypeLock.Lock()
-	defer userTypeLock.Unlock()
-	if ut = userTypeCache[rt]; ut != nil {
-		// Lost the race; not a problem.
-		return
-	}
-	ut = new(userTypeInfo)
+
+	// Construct a new userTypeInfo and atomically add it to the userTypeCache.
+	// If we lose the race, we'll waste a little CPU and create a little garbage
+	// but return the existing value anyway.
+
+	ut := new(userTypeInfo)
 	ut.base = rt
 	ut.user = rt
 	// A type that is just a cycle of pointers (such as type T *T) cannot
@@ -108,8 +98,8 @@
 	// 	ut.externalDec, ut.decIndir = xText, indir
 	// }
 
-	userTypeCache[rt] = ut
-	return
+	ui, _ := userTypeCache.LoadOrStore(rt, ut)
+	return ui.(*userTypeInfo), nil
 }
 
 var (
@@ -808,9 +798,8 @@
 }
 
 var (
-	registerLock       sync.RWMutex
-	nameToConcreteType = make(map[string]reflect.Type)
-	concreteTypeToName = make(map[reflect.Type]string)
+	nameToConcreteType sync.Map // map[string]reflect.Type
+	concreteTypeToName sync.Map // map[reflect.Type]string
 )
 
 // RegisterName is like Register but uses the provided name rather than the
@@ -820,21 +809,22 @@
 		// reserved for nil
 		panic("attempt to register empty name")
 	}
-	registerLock.Lock()
-	defer registerLock.Unlock()
+
 	ut := userType(reflect.TypeOf(value))
+
 	// Check for incompatible duplicates. The name must refer to the
 	// same user type, and vice versa.
-	if t, ok := nameToConcreteType[name]; ok && t != ut.user {
+
+	// Store the name and type provided by the user....
+	if t, dup := nameToConcreteType.LoadOrStore(name, reflect.TypeOf(value)); dup && t != ut.user {
 		panic(fmt.Sprintf("gob: registering duplicate types for %q: %s != %s", name, t, ut.user))
 	}
-	if n, ok := concreteTypeToName[ut.base]; ok && n != name {
+
+	// but the flattened type in the type table, since that's what decode needs.
+	if n, dup := concreteTypeToName.LoadOrStore(ut.base, name); dup && n != name {
+		nameToConcreteType.Delete(name)
 		panic(fmt.Sprintf("gob: registering duplicate names for %s: %q != %q", ut.user, n, name))
 	}
-	// Store the name and type provided by the user....
-	nameToConcreteType[name] = reflect.TypeOf(value)
-	// but the flattened type in the type table, since that's what decode needs.
-	concreteTypeToName[ut.base] = name
 }
 
 // Register records a type, identified by a value for that type, under its
diff --git a/libgo/go/encoding/gob/type_test.go b/libgo/go/encoding/gob/type_test.go
index e230d22..14f25d8 100644
--- a/libgo/go/encoding/gob/type_test.go
+++ b/libgo/go/encoding/gob/type_test.go
@@ -178,9 +178,7 @@
 		Register(tc.t)
 
 		tct := reflect.TypeOf(tc.t)
-		registerLock.RLock()
-		ct := nameToConcreteType[tc.name]
-		registerLock.RUnlock()
+		ct, _ := nameToConcreteType.Load(tc.name)
 		if ct != tct {
 			t.Errorf("nameToConcreteType[%q] = %v, want %v", tc.name, ct, tct)
 		}
@@ -188,7 +186,7 @@
 		if tct.Kind() == reflect.Ptr {
 			tct = tct.Elem()
 		}
-		if n := concreteTypeToName[tct]; n != tc.name {
+		if n, _ := concreteTypeToName.Load(tct); n != tc.name {
 			t.Errorf("concreteTypeToName[%v] got %v, want %v", tct, n, tc.name)
 		}
 	}
diff --git a/libgo/go/encoding/hex/hex.go b/libgo/go/encoding/hex/hex.go
index b43c1c4..2768f1b 100644
--- a/libgo/go/encoding/hex/hex.go
+++ b/libgo/go/encoding/hex/hex.go
@@ -12,10 +12,7 @@
 	"io"
 )
 
-var hextable = [16]byte{
-	'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
-	'a', 'b', 'c', 'd', 'e', 'f',
-}
+const hextable = "0123456789abcdef"
 
 // EncodedLen returns the length of an encoding of n source bytes.
 // Specifically, it returns n * 2.
diff --git a/libgo/go/encoding/json/bench_test.go b/libgo/go/encoding/json/bench_test.go
index cd7380b..85d7ae0 100644
--- a/libgo/go/encoding/json/bench_test.go
+++ b/libgo/go/encoding/json/bench_test.go
@@ -82,12 +82,14 @@
 		codeInit()
 		b.StartTimer()
 	}
-	enc := NewEncoder(ioutil.Discard)
-	for i := 0; i < b.N; i++ {
-		if err := enc.Encode(&codeStruct); err != nil {
-			b.Fatal("Encode:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		enc := NewEncoder(ioutil.Discard)
+		for pb.Next() {
+			if err := enc.Encode(&codeStruct); err != nil {
+				b.Fatal("Encode:", err)
+			}
 		}
-	}
+	})
 	b.SetBytes(int64(len(codeJSON)))
 }
 
@@ -97,11 +99,13 @@
 		codeInit()
 		b.StartTimer()
 	}
-	for i := 0; i < b.N; i++ {
-		if _, err := Marshal(&codeStruct); err != nil {
-			b.Fatal("Marshal:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if _, err := Marshal(&codeStruct); err != nil {
+				b.Fatal("Marshal:", err)
+			}
 		}
-	}
+	})
 	b.SetBytes(int64(len(codeJSON)))
 }
 
@@ -111,19 +115,21 @@
 		codeInit()
 		b.StartTimer()
 	}
-	var buf bytes.Buffer
-	dec := NewDecoder(&buf)
-	var r codeResponse
-	for i := 0; i < b.N; i++ {
-		buf.Write(codeJSON)
-		// hide EOF
-		buf.WriteByte('\n')
-		buf.WriteByte('\n')
-		buf.WriteByte('\n')
-		if err := dec.Decode(&r); err != nil {
-			b.Fatal("Decode:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		var buf bytes.Buffer
+		dec := NewDecoder(&buf)
+		var r codeResponse
+		for pb.Next() {
+			buf.Write(codeJSON)
+			// hide EOF
+			buf.WriteByte('\n')
+			buf.WriteByte('\n')
+			buf.WriteByte('\n')
+			if err := dec.Decode(&r); err != nil {
+				b.Fatal("Decode:", err)
+			}
 		}
-	}
+	})
 	b.SetBytes(int64(len(codeJSON)))
 }
 
@@ -155,12 +161,14 @@
 		codeInit()
 		b.StartTimer()
 	}
-	for i := 0; i < b.N; i++ {
-		var r codeResponse
-		if err := Unmarshal(codeJSON, &r); err != nil {
-			b.Fatal("Unmarshal:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			var r codeResponse
+			if err := Unmarshal(codeJSON, &r); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
 		}
-	}
+	})
 	b.SetBytes(int64(len(codeJSON)))
 }
 
@@ -170,54 +178,75 @@
 		codeInit()
 		b.StartTimer()
 	}
-	var r codeResponse
-	for i := 0; i < b.N; i++ {
-		if err := Unmarshal(codeJSON, &r); err != nil {
-			b.Fatal("Unmarshal:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		var r codeResponse
+		for pb.Next() {
+			if err := Unmarshal(codeJSON, &r); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
 		}
-	}
+	})
+	// TODO(bcmills): Is there a missing b.SetBytes here?
 }
 
 func BenchmarkUnmarshalString(b *testing.B) {
 	data := []byte(`"hello, world"`)
-	var s string
-
-	for i := 0; i < b.N; i++ {
-		if err := Unmarshal(data, &s); err != nil {
-			b.Fatal("Unmarshal:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		var s string
+		for pb.Next() {
+			if err := Unmarshal(data, &s); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
 		}
-	}
+	})
 }
 
 func BenchmarkUnmarshalFloat64(b *testing.B) {
-	var f float64
 	data := []byte(`3.14`)
-
-	for i := 0; i < b.N; i++ {
-		if err := Unmarshal(data, &f); err != nil {
-			b.Fatal("Unmarshal:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		var f float64
+		for pb.Next() {
+			if err := Unmarshal(data, &f); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
 		}
-	}
+	})
 }
 
 func BenchmarkUnmarshalInt64(b *testing.B) {
-	var x int64
 	data := []byte(`3`)
-
-	for i := 0; i < b.N; i++ {
-		if err := Unmarshal(data, &x); err != nil {
-			b.Fatal("Unmarshal:", err)
+	b.RunParallel(func(pb *testing.PB) {
+		var x int64
+		for pb.Next() {
+			if err := Unmarshal(data, &x); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
 		}
-	}
+	})
 }
 
 func BenchmarkIssue10335(b *testing.B) {
 	b.ReportAllocs()
-	var s struct{}
 	j := []byte(`{"a":{ }}`)
-	for n := 0; n < b.N; n++ {
-		if err := Unmarshal(j, &s); err != nil {
-			b.Fatal(err)
+	b.RunParallel(func(pb *testing.PB) {
+		var s struct{}
+		for pb.Next() {
+			if err := Unmarshal(j, &s); err != nil {
+				b.Fatal(err)
+			}
 		}
-	}
+	})
+}
+
+func BenchmarkUnmapped(b *testing.B) {
+	b.ReportAllocs()
+	j := []byte(`{"s": "hello", "y": 2, "o": {"x": 0}, "a": [1, 99, {"x": 1}]}`)
+	b.RunParallel(func(pb *testing.PB) {
+		var s struct{}
+		for pb.Next() {
+			if err := Unmarshal(j, &s); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
 }
diff --git a/libgo/go/encoding/json/decode.go b/libgo/go/encoding/json/decode.go
index 77fc460..420a07e 100644
--- a/libgo/go/encoding/json/decode.go
+++ b/libgo/go/encoding/json/decode.go
@@ -22,7 +22,8 @@
 )
 
 // Unmarshal parses the JSON-encoded data and stores the result
-// in the value pointed to by v.
+// in the value pointed to by v. If v is nil or not a pointer,
+// Unmarshal returns an InvalidUnmarshalError.
 //
 // Unmarshal uses the inverse of the encodings that
 // Marshal uses, allocating maps, slices, and pointers as necessary,
@@ -78,7 +79,9 @@
 // or if a JSON number overflows the target type, Unmarshal
 // skips that field and completes the unmarshaling as best it can.
 // If no more serious errors are encountered, Unmarshal returns
-// an UnmarshalTypeError describing the earliest such error.
+// an UnmarshalTypeError describing the earliest such error. In any
+// case, it's not guaranteed that all the remaining fields following
+// the problematic one will be unmarshaled into the target object.
 //
 // The JSON null value unmarshals into an interface, map, pointer, or slice
 // by setting that Go value to nil. Because null is often used in JSON to mean
diff --git a/libgo/go/encoding/json/encode.go b/libgo/go/encoding/json/encode.go
index 8f21dda..0371f0a 100644
--- a/libgo/go/encoding/json/encode.go
+++ b/libgo/go/encoding/json/encode.go
@@ -332,10 +332,7 @@
 
 type encoderFunc func(e *encodeState, v reflect.Value, opts encOpts)
 
-var encoderCache struct {
-	sync.RWMutex
-	m map[reflect.Type]encoderFunc
-}
+var encoderCache sync.Map // map[reflect.Type]encoderFunc
 
 func valueEncoder(v reflect.Value) encoderFunc {
 	if !v.IsValid() {
@@ -345,36 +342,31 @@
 }
 
 func typeEncoder(t reflect.Type) encoderFunc {
-	encoderCache.RLock()
-	f := encoderCache.m[t]
-	encoderCache.RUnlock()
-	if f != nil {
-		return f
+	if fi, ok := encoderCache.Load(t); ok {
+		return fi.(encoderFunc)
 	}
 
 	// To deal with recursive types, populate the map with an
 	// indirect func before we build it. This type waits on the
 	// real func (f) to be ready and then calls it. This indirect
 	// func is only used for recursive types.
-	encoderCache.Lock()
-	if encoderCache.m == nil {
-		encoderCache.m = make(map[reflect.Type]encoderFunc)
-	}
-	var wg sync.WaitGroup
+	var (
+		wg sync.WaitGroup
+		f  encoderFunc
+	)
 	wg.Add(1)
-	encoderCache.m[t] = func(e *encodeState, v reflect.Value, opts encOpts) {
+	fi, loaded := encoderCache.LoadOrStore(t, encoderFunc(func(e *encodeState, v reflect.Value, opts encOpts) {
 		wg.Wait()
 		f(e, v, opts)
+	}))
+	if loaded {
+		return fi.(encoderFunc)
 	}
-	encoderCache.Unlock()
 
-	// Compute fields without lock.
-	// Might duplicate effort but won't hold other computations back.
+	// Compute the real encoder and replace the indirect func with it.
 	f = newTypeEncoder(t, true)
 	wg.Done()
-	encoderCache.Lock()
-	encoderCache.m[t] = f
-	encoderCache.Unlock()
+	encoderCache.Store(t, f)
 	return f
 }
 
@@ -1101,7 +1093,22 @@
 			// Scan f.typ for fields to include.
 			for i := 0; i < f.typ.NumField(); i++ {
 				sf := f.typ.Field(i)
-				if sf.PkgPath != "" && !sf.Anonymous { // unexported
+				if sf.Anonymous {
+					t := sf.Type
+					if t.Kind() == reflect.Ptr {
+						t = t.Elem()
+					}
+					// If embedded, StructField.PkgPath is not a reliable
+					// indicator of whether the field is exported.
+					// See https://golang.org/issue/21122
+					if !isExported(t.Name()) && t.Kind() != reflect.Struct {
+						// Ignore embedded fields of unexported non-struct types.
+						// Do not ignore embedded fields of unexported struct types
+						// since they may have exported fields.
+						continue
+					}
+				} else if sf.PkgPath != "" {
+					// Ignore unexported non-embedded fields.
 					continue
 				}
 				tag := sf.Tag.Get("json")
@@ -1219,6 +1226,12 @@
 	return fields
 }
 
+// isExported reports whether the identifier is exported.
+func isExported(id string) bool {
+	r, _ := utf8.DecodeRuneInString(id)
+	return unicode.IsUpper(r)
+}
+
 // dominantField looks through the fields, all of which are known to
 // have the same name, to find the single field that dominates the
 // others using Go's embedding rules, modified by the presence of
diff --git a/libgo/go/encoding/json/encode_test.go b/libgo/go/encoding/json/encode_test.go
index 6d574cf..3fda6a0 100644
--- a/libgo/go/encoding/json/encode_test.go
+++ b/libgo/go/encoding/json/encode_test.go
@@ -253,23 +253,167 @@
 	}
 }
 
-type IntType int
+func TestAnonymousFields(t *testing.T) {
+	tests := []struct {
+		label     string             // Test name
+		makeInput func() interface{} // Function to create input value
+		want      string             // Expected JSON output
+	}{{
+		// Both S1 and S2 have a field named X. From the perspective of S,
+		// it is ambiguous which one X refers to.
+		// This should not serialize either field.
+		label: "AmbiguousField",
+		makeInput: func() interface{} {
+			type (
+				S1 struct{ x, X int }
+				S2 struct{ x, X int }
+				S  struct {
+					S1
+					S2
+				}
+			)
+			return S{S1{1, 2}, S2{3, 4}}
+		},
+		want: `{}`,
+	}, {
+		label: "DominantField",
+		// Both S1 and S2 have a field named X, but since S has an X field as
+		// well, it takes precedence over S1.X and S2.X.
+		makeInput: func() interface{} {
+			type (
+				S1 struct{ x, X int }
+				S2 struct{ x, X int }
+				S  struct {
+					S1
+					S2
+					x, X int
+				}
+			)
+			return S{S1{1, 2}, S2{3, 4}, 5, 6}
+		},
+		want: `{"X":6}`,
+	}, {
+		// Unexported embedded field of non-struct type should not be serialized.
+		label: "UnexportedEmbeddedInt",
+		makeInput: func() interface{} {
+			type (
+				myInt int
+				S     struct{ myInt }
+			)
+			return S{5}
+		},
+		want: `{}`,
+	}, {
+		// Exported embedded field of non-struct type should be serialized.
+		label: "ExportedEmbeddedInt",
+		makeInput: func() interface{} {
+			type (
+				MyInt int
+				S     struct{ MyInt }
+			)
+			return S{5}
+		},
+		want: `{"MyInt":5}`,
+	}, {
+		// Unexported embedded field of pointer to non-struct type
+		// should not be serialized.
+		label: "UnexportedEmbeddedIntPointer",
+		makeInput: func() interface{} {
+			type (
+				myInt int
+				S     struct{ *myInt }
+			)
+			s := S{new(myInt)}
+			*s.myInt = 5
+			return s
+		},
+		want: `{}`,
+	}, {
+		// Exported embedded field of pointer to non-struct type
+		// should be serialized.
+		label: "ExportedEmbeddedIntPointer",
+		makeInput: func() interface{} {
+			type (
+				MyInt int
+				S     struct{ *MyInt }
+			)
+			s := S{new(MyInt)}
+			*s.MyInt = 5
+			return s
+		},
+		want: `{"MyInt":5}`,
+	}, {
+		// Exported fields of embedded structs should have their
+		// exported fields be serialized regardless of whether the struct types
+		// themselves are exported.
+		label: "EmbeddedStruct",
+		makeInput: func() interface{} {
+			type (
+				s1 struct{ x, X int }
+				S2 struct{ y, Y int }
+				S  struct {
+					s1
+					S2
+				}
+			)
+			return S{s1{1, 2}, S2{3, 4}}
+		},
+		want: `{"X":2,"Y":4}`,
+	}, {
+		// Exported fields of pointers to embedded structs should have their
+		// exported fields be serialized regardless of whether the struct types
+		// themselves are exported.
+		label: "EmbeddedStructPointer",
+		makeInput: func() interface{} {
+			type (
+				s1 struct{ x, X int }
+				S2 struct{ y, Y int }
+				S  struct {
+					*s1
+					*S2
+				}
+			)
+			return S{&s1{1, 2}, &S2{3, 4}}
+		},
+		want: `{"X":2,"Y":4}`,
+	}, {
+		// Exported fields on embedded unexported structs at multiple levels
+		// of nesting should still be serialized.
+		label: "NestedStructAndInts",
+		makeInput: func() interface{} {
+			type (
+				MyInt1 int
+				MyInt2 int
+				myInt  int
+				s2     struct {
+					MyInt2
+					myInt
+				}
+				s1 struct {
+					MyInt1
+					myInt
+					s2
+				}
+				S struct {
+					s1
+					myInt
+				}
+			)
+			return S{s1{1, 2, s2{3, 4}}, 6}
+		},
+		want: `{"MyInt1":1,"MyInt2":3}`,
+	}}
 
-type MyStruct struct {
-	IntType
-}
-
-func TestAnonymousNonstruct(t *testing.T) {
-	var i IntType = 11
-	a := MyStruct{i}
-	const want = `{"IntType":11}`
-
-	b, err := Marshal(a)
-	if err != nil {
-		t.Fatalf("Marshal: %v", err)
-	}
-	if got := string(b); got != want {
-		t.Errorf("got %q, want %q", got, want)
+	for _, tt := range tests {
+		t.Run(tt.label, func(t *testing.T) {
+			b, err := Marshal(tt.makeInput())
+			if err != nil {
+				t.Fatalf("Marshal() = %v, want nil error", err)
+			}
+			if string(b) != tt.want {
+				t.Fatalf("Marshal() = %q, want %q", b, tt.want)
+			}
+		})
 	}
 }
 
diff --git a/libgo/go/encoding/json/scanner.go b/libgo/go/encoding/json/scanner.go
index a6d8706..ae34418 100644
--- a/libgo/go/encoding/json/scanner.go
+++ b/libgo/go/encoding/json/scanner.go
@@ -15,6 +15,11 @@
 
 import "strconv"
 
+// Valid reports whether data is a valid JSON encoding.
+func Valid(data []byte) bool {
+	return checkValid(data, &scanner{}) == nil
+}
+
 // checkValid verifies that data is valid JSON-encoded data.
 // scan is passed in for use by checkValid to avoid an allocation.
 func checkValid(data []byte, scan *scanner) error {
diff --git a/libgo/go/encoding/json/scanner_test.go b/libgo/go/encoding/json/scanner_test.go
index c5c1be3..0d4518a 100644
--- a/libgo/go/encoding/json/scanner_test.go
+++ b/libgo/go/encoding/json/scanner_test.go
@@ -12,6 +12,26 @@
 	"testing"
 )
 
+var validTests = []struct {
+	data string
+	ok   bool
+}{
+	{`foo`, false},
+	{`}{`, false},
+	{`{]`, false},
+	{`{}`, true},
+	{`{"foo":"bar"}`, true},
+	{`{"foo":"bar","bar":{"baz":["qux"]}}`, true},
+}
+
+func TestValid(t *testing.T) {
+	for _, tt := range validTests {
+		if ok := Valid([]byte(tt.data)); ok != tt.ok {
+			t.Errorf("Valid(%#q) = %v, want %v", tt.data, ok, tt.ok)
+		}
+	}
+}
+
 // Tests of simple examples.
 
 type example struct {
diff --git a/libgo/go/encoding/json/stream_test.go b/libgo/go/encoding/json/stream_test.go
index 84edeb1..d0b3ffb 100644
--- a/libgo/go/encoding/json/stream_test.go
+++ b/libgo/go/encoding/json/stream_test.go
@@ -268,11 +268,13 @@
 		X, Y string
 	}
 	v := &T{"foo", "bar"}
-	for i := 0; i < b.N; i++ {
-		if err := NewEncoder(ioutil.Discard).Encode(v); err != nil {
-			b.Fatal(err)
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if err := NewEncoder(ioutil.Discard).Encode(v); err != nil {
+				b.Fatal(err)
+			}
 		}
-	}
+	})
 }
 
 type tokenStreamCase struct {
diff --git a/libgo/go/encoding/pem/pem.go b/libgo/go/encoding/pem/pem.go
index fbf4999..5e1ab90 100644
--- a/libgo/go/encoding/pem/pem.go
+++ b/libgo/go/encoding/pem/pem.go
@@ -135,20 +135,26 @@
 		return decodeError(data, rest)
 	}
 
-	// After the "-----" of the ending line should be the same type and a
-	// final five dashes.
+	// After the "-----" of the ending line, there should be the same type
+	// and then a final five dashes.
 	endTrailer := rest[endTrailerIndex:]
 	endTrailerLen := len(typeLine) + len(pemEndOfLine)
 	if len(endTrailer) < endTrailerLen {
 		return decodeError(data, rest)
 	}
 
+	restOfEndLine := endTrailer[endTrailerLen:]
 	endTrailer = endTrailer[:endTrailerLen]
 	if !bytes.HasPrefix(endTrailer, typeLine) ||
 		!bytes.HasSuffix(endTrailer, pemEndOfLine) {
 		return decodeError(data, rest)
 	}
 
+	// The line must end with only whitespace.
+	if s, _ := getLine(restOfEndLine); len(s) != 0 {
+		return decodeError(data, rest)
+	}
+
 	base64Data := removeWhitespace(rest[:endIndex])
 	p.Bytes = make([]byte, base64.StdEncoding.DecodedLen(len(base64Data)))
 	n, err := base64.StdEncoding.Decode(p.Bytes, base64Data)
diff --git a/libgo/go/encoding/pem/pem_test.go b/libgo/go/encoding/pem/pem_test.go
index 6321dec..1a1250a 100644
--- a/libgo/go/encoding/pem/pem_test.go
+++ b/libgo/go/encoding/pem/pem_test.go
@@ -83,6 +83,16 @@
 dGVzdA==
 -----END FOO----`
 
+const pemTooManyEndingDashes = `
+-----BEGIN FOO-----
+dGVzdA==
+-----END FOO------`
+
+const pemTrailingNonWhitespace = `
+-----BEGIN FOO-----
+dGVzdA==
+-----END FOO----- .`
+
 const pemWrongEndingType = `
 -----BEGIN FOO-----
 dGVzdA==
@@ -102,6 +112,14 @@
 		pemTooFewEndingDashes,
 	},
 	{
+		"too many trailing dashes",
+		pemTooManyEndingDashes,
+	},
+	{
+		"trailing non-whitespace",
+		pemTrailingNonWhitespace,
+	},
+	{
 		"incorrect ending type",
 		pemWrongEndingType,
 	},
@@ -188,10 +206,20 @@
 }
 
 func TestFuzz(t *testing.T) {
+	// PEM is a text-based format. Assume header fields with leading/trailing spaces
+	// or embedded newlines will not round trip correctly and don't need to be tested.
+	isBad := func(s string) bool {
+		return strings.ContainsAny(s, "\r\n") || strings.TrimSpace(s) != s
+	}
+
 	testRoundtrip := func(block Block) bool {
-		for key := range block.Headers {
-			if strings.Contains(key, ":") {
-				// Keys with colons cannot be encoded.
+		if isBad(block.Type) {
+			return true
+		}
+		for key, val := range block.Headers {
+			// Reject bad key/val.
+			// Also, keys with colons cannot be encoded, because : is the key: val separator.
+			if isBad(key) || isBad(val) || strings.Contains(key, ":") {
 				return true
 			}
 		}
diff --git a/libgo/go/encoding/xml/marshal_test.go b/libgo/go/encoding/xml/marshal_test.go
index 0126146..674c6b5 100644
--- a/libgo/go/encoding/xml/marshal_test.go
+++ b/libgo/go/encoding/xml/marshal_test.go
@@ -1652,28 +1652,31 @@
 		if test.UnmarshalOnly {
 			continue
 		}
-		data, err := Marshal(test.Value)
-		if err != nil {
-			if test.MarshalError == "" {
-				t.Errorf("#%d: marshal(%#v): %s", idx, test.Value, err)
-				continue
+
+		t.Run(fmt.Sprintf("%d", idx), func(t *testing.T) {
+			data, err := Marshal(test.Value)
+			if err != nil {
+				if test.MarshalError == "" {
+					t.Errorf("marshal(%#v): %s", test.Value, err)
+					return
+				}
+				if !strings.Contains(err.Error(), test.MarshalError) {
+					t.Errorf("marshal(%#v): %s, want %q", test.Value, err, test.MarshalError)
+				}
+				return
 			}
-			if !strings.Contains(err.Error(), test.MarshalError) {
-				t.Errorf("#%d: marshal(%#v): %s, want %q", idx, test.Value, err, test.MarshalError)
+			if test.MarshalError != "" {
+				t.Errorf("Marshal succeeded, want error %q", test.MarshalError)
+				return
 			}
-			continue
-		}
-		if test.MarshalError != "" {
-			t.Errorf("#%d: Marshal succeeded, want error %q", idx, test.MarshalError)
-			continue
-		}
-		if got, want := string(data), test.ExpectXML; got != want {
-			if strings.Contains(want, "\n") {
-				t.Errorf("#%d: marshal(%#v):\nHAVE:\n%s\nWANT:\n%s", idx, test.Value, got, want)
-			} else {
-				t.Errorf("#%d: marshal(%#v):\nhave %#q\nwant %#q", idx, test.Value, got, want)
+			if got, want := string(data), test.ExpectXML; got != want {
+				if strings.Contains(want, "\n") {
+					t.Errorf("marshal(%#v):\nHAVE:\n%s\nWANT:\n%s", test.Value, got, want)
+				} else {
+					t.Errorf("marshal(%#v):\nhave %#q\nwant %#q", test.Value, got, want)
+				}
 			}
-		}
+		})
 	}
 }
 
@@ -1781,27 +1784,29 @@
 		dest := reflect.New(vt.Elem()).Interface()
 		err := Unmarshal([]byte(test.ExpectXML), dest)
 
-		switch fix := dest.(type) {
-		case *Feed:
-			fix.Author.InnerXML = ""
-			for i := range fix.Entry {
-				fix.Entry[i].Author.InnerXML = ""
+		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
+			switch fix := dest.(type) {
+			case *Feed:
+				fix.Author.InnerXML = ""
+				for i := range fix.Entry {
+					fix.Entry[i].Author.InnerXML = ""
+				}
 			}
-		}
 
-		if err != nil {
-			if test.UnmarshalError == "" {
-				t.Errorf("#%d: unmarshal(%#v): %s", i, test.ExpectXML, err)
-				continue
+			if err != nil {
+				if test.UnmarshalError == "" {
+					t.Errorf("unmarshal(%#v): %s", test.ExpectXML, err)
+					return
+				}
+				if !strings.Contains(err.Error(), test.UnmarshalError) {
+					t.Errorf("unmarshal(%#v): %s, want %q", test.ExpectXML, err, test.UnmarshalError)
+				}
+				return
 			}
-			if !strings.Contains(err.Error(), test.UnmarshalError) {
-				t.Errorf("#%d: unmarshal(%#v): %s, want %q", i, test.ExpectXML, err, test.UnmarshalError)
+			if got, want := dest, test.Value; !reflect.DeepEqual(got, want) {
+				t.Errorf("unmarshal(%q):\nhave %#v\nwant %#v", test.ExpectXML, got, want)
 			}
-			continue
-		}
-		if got, want := dest, test.Value; !reflect.DeepEqual(got, want) {
-			t.Errorf("#%d: unmarshal(%q):\nhave %#v\nwant %#v", i, test.ExpectXML, got, want)
-		}
+		})
 	}
 }
 
@@ -1896,17 +1901,21 @@
 
 func BenchmarkMarshal(b *testing.B) {
 	b.ReportAllocs()
-	for i := 0; i < b.N; i++ {
-		Marshal(atomValue)
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			Marshal(atomValue)
+		}
+	})
 }
 
 func BenchmarkUnmarshal(b *testing.B) {
 	b.ReportAllocs()
 	xml := []byte(atomXml)
-	for i := 0; i < b.N; i++ {
-		Unmarshal(xml, &Feed{})
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			Unmarshal(xml, &Feed{})
+		}
+	})
 }
 
 // golang.org/issue/6556
@@ -2428,10 +2437,7 @@
 	err := Unmarshal([]byte(data), &struct {
 		B byte `xml:"b,attr,omitempty"`
 	}{})
-
-	// For Go 1.8.1 we've restored the old "no errors reported" behavior.
-	// We'll try again in Go 1.9 to report errors.
-	if err != nil {
-		t.Errorf("Unmarshal: expected nil, got error")
+	if err == nil {
+		t.Errorf("Unmarshal: expected error, got nil")
 	}
 }
diff --git a/libgo/go/encoding/xml/read.go b/libgo/go/encoding/xml/read.go
index 799b57e..000d9fb 100644
--- a/libgo/go/encoding/xml/read.go
+++ b/libgo/go/encoding/xml/read.go
@@ -120,6 +120,9 @@
 // Unmarshal maps an XML element to a pointer by setting the pointer
 // to a freshly allocated value and then mapping the element to that value.
 //
+// A missing element or empty attribute value will be unmarshaled as a zero value.
+// If the field is a slice, a zero value will be appended to the field. Otherwise, the
+// field will be set to its zero value.
 func Unmarshal(data []byte, v interface{}) error {
 	return NewDecoder(bytes.NewReader(data)).Decode(v)
 }
@@ -211,7 +214,7 @@
 // unmarshalTextInterface unmarshals a single XML element into val.
 // The chardata contained in the element (but not its children)
 // is passed to the text unmarshaler.
-func (p *Decoder) unmarshalTextInterface(val encoding.TextUnmarshaler, start *StartElement) error {
+func (p *Decoder) unmarshalTextInterface(val encoding.TextUnmarshaler) error {
 	var buf []byte
 	depth := 1
 	for depth > 0 {
@@ -285,8 +288,7 @@
 		return nil
 	}
 
-	copyValue(val, []byte(attr.Value))
-	return nil
+	return copyValue(val, []byte(attr.Value))
 }
 
 var (
@@ -342,13 +344,13 @@
 	}
 
 	if val.CanInterface() && val.Type().Implements(textUnmarshalerType) {
-		return p.unmarshalTextInterface(val.Interface().(encoding.TextUnmarshaler), start)
+		return p.unmarshalTextInterface(val.Interface().(encoding.TextUnmarshaler))
 	}
 
 	if val.CanAddr() {
 		pv := val.Addr()
 		if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
-			return p.unmarshalTextInterface(pv.Interface().(encoding.TextUnmarshaler), start)
+			return p.unmarshalTextInterface(pv.Interface().(encoding.TextUnmarshaler))
 		}
 	}
 
@@ -608,24 +610,40 @@
 	default:
 		return errors.New("cannot unmarshal into " + dst0.Type().String())
 	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		if len(src) == 0 {
+			dst.SetInt(0)
+			return nil
+		}
 		itmp, err := strconv.ParseInt(string(src), 10, dst.Type().Bits())
 		if err != nil {
 			return err
 		}
 		dst.SetInt(itmp)
 	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		if len(src) == 0 {
+			dst.SetUint(0)
+			return nil
+		}
 		utmp, err := strconv.ParseUint(string(src), 10, dst.Type().Bits())
 		if err != nil {
 			return err
 		}
 		dst.SetUint(utmp)
 	case reflect.Float32, reflect.Float64:
+		if len(src) == 0 {
+			dst.SetFloat(0)
+			return nil
+		}
 		ftmp, err := strconv.ParseFloat(string(src), dst.Type().Bits())
 		if err != nil {
 			return err
 		}
 		dst.SetFloat(ftmp)
 	case reflect.Bool:
+		if len(src) == 0 {
+			dst.SetBool(false)
+			return nil
+		}
 		value, err := strconv.ParseBool(strings.TrimSpace(string(src)))
 		if err != nil {
 			return err
diff --git a/libgo/go/encoding/xml/read_test.go b/libgo/go/encoding/xml/read_test.go
index 273c303..a1eb516 100644
--- a/libgo/go/encoding/xml/read_test.go
+++ b/libgo/go/encoding/xml/read_test.go
@@ -752,3 +752,159 @@
 		t.Errorf("NotInnerXML = %v, want nil", v.NotInnerXML)
 	}
 }
+
+type Child struct {
+	G struct {
+		I int
+	}
+}
+
+type ChildToEmbed struct {
+	X bool
+}
+
+type Parent struct {
+	I        int
+	IPtr     *int
+	Is       []int
+	IPtrs    []*int
+	F        float32
+	FPtr     *float32
+	Fs       []float32
+	FPtrs    []*float32
+	B        bool
+	BPtr     *bool
+	Bs       []bool
+	BPtrs    []*bool
+	Bytes    []byte
+	BytesPtr *[]byte
+	S        string
+	SPtr     *string
+	Ss       []string
+	SPtrs    []*string
+	MyI      MyInt
+	Child    Child
+	Children []Child
+	ChildPtr *Child
+	ChildToEmbed
+}
+
+const (
+	emptyXML = `
+<Parent>
+    <I></I>
+    <IPtr></IPtr>
+    <Is></Is>
+    <IPtrs></IPtrs>
+    <F></F>
+    <FPtr></FPtr>
+    <Fs></Fs>
+    <FPtrs></FPtrs>
+    <B></B>
+    <BPtr></BPtr>
+    <Bs></Bs>
+    <BPtrs></BPtrs>
+    <Bytes></Bytes>
+    <BytesPtr></BytesPtr>
+    <S></S>
+    <SPtr></SPtr>
+    <Ss></Ss>
+    <SPtrs></SPtrs>
+    <MyI></MyI>
+    <Child></Child>
+    <Children></Children>
+    <ChildPtr></ChildPtr>
+    <X></X>
+</Parent>
+`
+)
+
+// github.com/golang/go/issues/13417
+func TestUnmarshalEmptyValues(t *testing.T) {
+	// Test first with a zero-valued dst.
+	v := new(Parent)
+	if err := Unmarshal([]byte(emptyXML), v); err != nil {
+		t.Fatalf("zero: Unmarshal failed: got %v", err)
+	}
+
+	zBytes, zInt, zStr, zFloat, zBool := []byte{}, 0, "", float32(0), false
+	want := &Parent{
+		IPtr:         &zInt,
+		Is:           []int{zInt},
+		IPtrs:        []*int{&zInt},
+		FPtr:         &zFloat,
+		Fs:           []float32{zFloat},
+		FPtrs:        []*float32{&zFloat},
+		BPtr:         &zBool,
+		Bs:           []bool{zBool},
+		BPtrs:        []*bool{&zBool},
+		Bytes:        []byte{},
+		BytesPtr:     &zBytes,
+		SPtr:         &zStr,
+		Ss:           []string{zStr},
+		SPtrs:        []*string{&zStr},
+		Children:     []Child{{}},
+		ChildPtr:     new(Child),
+		ChildToEmbed: ChildToEmbed{},
+	}
+	if !reflect.DeepEqual(v, want) {
+		t.Fatalf("zero: Unmarshal:\nhave:  %#+v\nwant: %#+v", v, want)
+	}
+
+	// Test with a pre-populated dst.
+	// Multiple addressable copies, as pointer-to fields will replace value during unmarshal.
+	vBytes0, vInt0, vStr0, vFloat0, vBool0 := []byte("x"), 1, "x", float32(1), true
+	vBytes1, vInt1, vStr1, vFloat1, vBool1 := []byte("x"), 1, "x", float32(1), true
+	vInt2, vStr2, vFloat2, vBool2 := 1, "x", float32(1), true
+	v = &Parent{
+		I:            vInt0,
+		IPtr:         &vInt1,
+		Is:           []int{vInt0},
+		IPtrs:        []*int{&vInt2},
+		F:            vFloat0,
+		FPtr:         &vFloat1,
+		Fs:           []float32{vFloat0},
+		FPtrs:        []*float32{&vFloat2},
+		B:            vBool0,
+		BPtr:         &vBool1,
+		Bs:           []bool{vBool0},
+		BPtrs:        []*bool{&vBool2},
+		Bytes:        vBytes0,
+		BytesPtr:     &vBytes1,
+		S:            vStr0,
+		SPtr:         &vStr1,
+		Ss:           []string{vStr0},
+		SPtrs:        []*string{&vStr2},
+		MyI:          MyInt(vInt0),
+		Child:        Child{G: struct{ I int }{I: vInt0}},
+		Children:     []Child{{G: struct{ I int }{I: vInt0}}},
+		ChildPtr:     &Child{G: struct{ I int }{I: vInt0}},
+		ChildToEmbed: ChildToEmbed{X: vBool0},
+	}
+	if err := Unmarshal([]byte(emptyXML), v); err != nil {
+		t.Fatalf("populated: Unmarshal failed: got %v", err)
+	}
+
+	want = &Parent{
+		IPtr:     &zInt,
+		Is:       []int{vInt0, zInt},
+		IPtrs:    []*int{&vInt0, &zInt},
+		FPtr:     &zFloat,
+		Fs:       []float32{vFloat0, zFloat},
+		FPtrs:    []*float32{&vFloat0, &zFloat},
+		BPtr:     &zBool,
+		Bs:       []bool{vBool0, zBool},
+		BPtrs:    []*bool{&vBool0, &zBool},
+		Bytes:    []byte{},
+		BytesPtr: &zBytes,
+		SPtr:     &zStr,
+		Ss:       []string{vStr0, zStr},
+		SPtrs:    []*string{&vStr0, &zStr},
+		Child:    Child{G: struct{ I int }{I: vInt0}}, // I should == zInt0? (zero value)
+		Children: []Child{{G: struct{ I int }{I: vInt0}}, {}},
+		ChildPtr: &Child{G: struct{ I int }{I: vInt0}}, // I should == zInt0? (zero value)
+	}
+	if !reflect.DeepEqual(v, want) {
+		t.Fatalf("populated: Unmarshal:\nhave:  %#+v\nwant: %#+v", v, want)
+	}
+}
diff --git a/libgo/go/encoding/xml/typeinfo.go b/libgo/go/encoding/xml/typeinfo.go
index 6623c78..751caa9 100644
--- a/libgo/go/encoding/xml/typeinfo.go
+++ b/libgo/go/encoding/xml/typeinfo.go
@@ -42,21 +42,18 @@
 	fMode = fElement | fAttr | fCDATA | fCharData | fInnerXml | fComment | fAny
 )
 
-var tinfoMap = make(map[reflect.Type]*typeInfo)
-var tinfoLock sync.RWMutex
+var tinfoMap sync.Map // map[reflect.Type]*typeInfo
 
 var nameType = reflect.TypeOf(Name{})
 
 // getTypeInfo returns the typeInfo structure with details necessary
 // for marshaling and unmarshaling typ.
 func getTypeInfo(typ reflect.Type) (*typeInfo, error) {
-	tinfoLock.RLock()
-	tinfo, ok := tinfoMap[typ]
-	tinfoLock.RUnlock()
-	if ok {
-		return tinfo, nil
+	if ti, ok := tinfoMap.Load(typ); ok {
+		return ti.(*typeInfo), nil
 	}
-	tinfo = &typeInfo{}
+
+	tinfo := &typeInfo{}
 	if typ.Kind() == reflect.Struct && typ != nameType {
 		n := typ.NumField()
 		for i := 0; i < n; i++ {
@@ -105,10 +102,9 @@
 			}
 		}
 	}
-	tinfoLock.Lock()
-	tinfoMap[typ] = tinfo
-	tinfoLock.Unlock()
-	return tinfo, nil
+
+	ti, _ := tinfoMap.LoadOrStore(typ, tinfo)
+	return ti.(*typeInfo), nil
 }
 
 // structFieldInfo builds and returns a fieldInfo for f.
diff --git a/libgo/go/encoding/xml/xml_test.go b/libgo/go/encoding/xml/xml_test.go
index f43a5e7..dad6ed9 100644
--- a/libgo/go/encoding/xml/xml_test.go
+++ b/libgo/go/encoding/xml/xml_test.go
@@ -797,37 +797,3 @@
 		}
 	}
 }
-
-func TestIssue19333(t *testing.T) {
-	type X struct {
-		XMLName Name `xml:"X"`
-		A       int  `xml:",attr"`
-		C       int
-	}
-
-	var tests = []struct {
-		input string
-		ok    bool
-	}{
-		{`<X></X>`, true},
-		{`<X A=""></X>`, true},
-		{`<X A="bad"></X>`, true},
-		{`<X></X>`, true},
-		{`<X><C></C></X>`, false},
-		{`<X><C/></X>`, false},
-		{`<X><C>bad</C></X>`, false},
-	}
-
-	for _, tt := range tests {
-		err := Unmarshal([]byte(tt.input), new(X))
-		if tt.ok {
-			if err != nil {
-				t.Errorf("%s: unexpected error: %v", tt.input, err)
-			}
-		} else {
-			if err == nil {
-				t.Errorf("%s: unexpected success", tt.input)
-			}
-		}
-	}
-}
diff --git a/libgo/go/expvar/expvar.go b/libgo/go/expvar/expvar.go
index 7339fa0..64dae70 100644
--- a/libgo/go/expvar/expvar.go
+++ b/libgo/go/expvar/expvar.go
@@ -99,9 +99,9 @@
 
 // Map is a string-to-Var map variable that satisfies the Var interface.
 type Map struct {
-	mu   sync.RWMutex
-	m    map[string]Var
-	keys []string // sorted
+	m      sync.Map // map[string]Var
+	keysMu sync.RWMutex
+	keys   []string // sorted
 }
 
 // KeyValue represents a single entry in a Map.
@@ -111,12 +111,10 @@
 }
 
 func (v *Map) String() string {
-	v.mu.RLock()
-	defer v.mu.RUnlock()
 	var b bytes.Buffer
 	fmt.Fprintf(&b, "{")
 	first := true
-	v.doLocked(func(kv KeyValue) {
+	v.Do(func(kv KeyValue) {
 		if !first {
 			fmt.Fprintf(&b, ", ")
 		}
@@ -127,79 +125,66 @@
 	return b.String()
 }
 
-func (v *Map) Init() *Map {
-	v.m = make(map[string]Var)
-	return v
-}
+func (v *Map) Init() *Map { return v }
 
 // updateKeys updates the sorted list of keys in v.keys.
-// must be called with v.mu held.
-func (v *Map) updateKeys() {
-	if len(v.m) == len(v.keys) {
-		// No new key.
-		return
-	}
-	v.keys = v.keys[:0]
-	for k := range v.m {
-		v.keys = append(v.keys, k)
-	}
+func (v *Map) addKey(key string) {
+	v.keysMu.Lock()
+	defer v.keysMu.Unlock()
+	v.keys = append(v.keys, key)
 	sort.Strings(v.keys)
 }
 
 func (v *Map) Get(key string) Var {
-	v.mu.RLock()
-	defer v.mu.RUnlock()
-	return v.m[key]
+	i, _ := v.m.Load(key)
+	av, _ := i.(Var)
+	return av
 }
 
 func (v *Map) Set(key string, av Var) {
-	v.mu.Lock()
-	defer v.mu.Unlock()
-	v.m[key] = av
-	v.updateKeys()
+	// Before we store the value, check to see whether the key is new. Try a Load
+	// before LoadOrStore: LoadOrStore causes the key interface to escape even on
+	// the Load path.
+	if _, ok := v.m.Load(key); !ok {
+		if _, dup := v.m.LoadOrStore(key, av); !dup {
+			v.addKey(key)
+			return
+		}
+	}
+
+	v.m.Store(key, av)
 }
 
+// Add adds delta to the *Int value stored under the given map key.
 func (v *Map) Add(key string, delta int64) {
-	v.mu.RLock()
-	av, ok := v.m[key]
-	v.mu.RUnlock()
+	i, ok := v.m.Load(key)
 	if !ok {
-		// check again under the write lock
-		v.mu.Lock()
-		av, ok = v.m[key]
-		if !ok {
-			av = new(Int)
-			v.m[key] = av
-			v.updateKeys()
+		var dup bool
+		i, dup = v.m.LoadOrStore(key, new(Int))
+		if !dup {
+			v.addKey(key)
 		}
-		v.mu.Unlock()
 	}
 
 	// Add to Int; ignore otherwise.
-	if iv, ok := av.(*Int); ok {
+	if iv, ok := i.(*Int); ok {
 		iv.Add(delta)
 	}
 }
 
 // AddFloat adds delta to the *Float value stored under the given map key.
 func (v *Map) AddFloat(key string, delta float64) {
-	v.mu.RLock()
-	av, ok := v.m[key]
-	v.mu.RUnlock()
+	i, ok := v.m.Load(key)
 	if !ok {
-		// check again under the write lock
-		v.mu.Lock()
-		av, ok = v.m[key]
-		if !ok {
-			av = new(Float)
-			v.m[key] = av
-			v.updateKeys()
+		var dup bool
+		i, dup = v.m.LoadOrStore(key, new(Float))
+		if !dup {
+			v.addKey(key)
 		}
-		v.mu.Unlock()
 	}
 
 	// Add to Float; ignore otherwise.
-	if iv, ok := av.(*Float); ok {
+	if iv, ok := i.(*Float); ok {
 		iv.Add(delta)
 	}
 }
@@ -208,45 +193,34 @@
 // The map is locked during the iteration,
 // but existing entries may be concurrently updated.
 func (v *Map) Do(f func(KeyValue)) {
-	v.mu.RLock()
-	defer v.mu.RUnlock()
-	v.doLocked(f)
-}
-
-// doLocked calls f for each entry in the map.
-// v.mu must be held for reads.
-func (v *Map) doLocked(f func(KeyValue)) {
+	v.keysMu.RLock()
+	defer v.keysMu.RUnlock()
 	for _, k := range v.keys {
-		f(KeyValue{k, v.m[k]})
+		i, _ := v.m.Load(k)
+		f(KeyValue{k, i.(Var)})
 	}
 }
 
 // String is a string variable, and satisfies the Var interface.
 type String struct {
-	mu sync.RWMutex
-	s  string
+	s atomic.Value // string
 }
 
 func (v *String) Value() string {
-	v.mu.RLock()
-	defer v.mu.RUnlock()
-	return v.s
+	p, _ := v.s.Load().(string)
+	return p
 }
 
 // String implements the Val interface. To get the unquoted string
 // use Value.
 func (v *String) String() string {
-	v.mu.RLock()
-	s := v.s
-	v.mu.RUnlock()
+	s := v.Value()
 	b, _ := json.Marshal(s)
 	return string(b)
 }
 
 func (v *String) Set(value string) {
-	v.mu.Lock()
-	defer v.mu.Unlock()
-	v.s = value
+	v.s.Store(value)
 }
 
 // Func implements Var by calling the function
@@ -264,21 +238,20 @@
 
 // All published variables.
 var (
-	mutex   sync.RWMutex
-	vars    = make(map[string]Var)
-	varKeys []string // sorted
+	vars      sync.Map // map[string]Var
+	varKeysMu sync.RWMutex
+	varKeys   []string // sorted
 )
 
 // Publish declares a named exported variable. This should be called from a
 // package's init function when it creates its Vars. If the name is already
 // registered then this will log.Panic.
 func Publish(name string, v Var) {
-	mutex.Lock()
-	defer mutex.Unlock()
-	if _, existing := vars[name]; existing {
+	if _, dup := vars.LoadOrStore(name, v); dup {
 		log.Panicln("Reuse of exported var name:", name)
 	}
-	vars[name] = v
+	varKeysMu.Lock()
+	defer varKeysMu.Unlock()
 	varKeys = append(varKeys, name)
 	sort.Strings(varKeys)
 }
@@ -286,9 +259,9 @@
 // Get retrieves a named exported variable. It returns nil if the name has
 // not been registered.
 func Get(name string) Var {
-	mutex.RLock()
-	defer mutex.RUnlock()
-	return vars[name]
+	i, _ := vars.Load(name)
+	v, _ := i.(Var)
+	return v
 }
 
 // Convenience functions for creating new exported variables.
@@ -321,10 +294,11 @@
 // The global variable map is locked during the iteration,
 // but existing entries may be concurrently updated.
 func Do(f func(KeyValue)) {
-	mutex.RLock()
-	defer mutex.RUnlock()
+	varKeysMu.RLock()
+	defer varKeysMu.RUnlock()
 	for _, k := range varKeys {
-		f(KeyValue{k, vars[k]})
+		val, _ := vars.Load(k)
+		f(KeyValue{k, val.(Var)})
 	}
 }
 
diff --git a/libgo/go/expvar/expvar_test.go b/libgo/go/expvar/expvar_test.go
index 0efa864..7014063 100644
--- a/libgo/go/expvar/expvar_test.go
+++ b/libgo/go/expvar/expvar_test.go
@@ -7,21 +7,25 @@
 import (
 	"bytes"
 	"encoding/json"
+	"fmt"
 	"net"
 	"net/http/httptest"
 	"reflect"
 	"runtime"
 	"strconv"
 	"sync"
+	"sync/atomic"
 	"testing"
 )
 
 // RemoveAll removes all exported variables.
 // This is for tests only.
 func RemoveAll() {
-	mutex.Lock()
-	defer mutex.Unlock()
-	vars = make(map[string]Var)
+	varKeysMu.Lock()
+	defer varKeysMu.Unlock()
+	for _, k := range varKeys {
+		vars.Delete(k)
+	}
 	varKeys = nil
 }
 
@@ -36,8 +40,8 @@
 func TestInt(t *testing.T) {
 	RemoveAll()
 	reqs := NewInt("requests")
-	if reqs.i != 0 {
-		t.Errorf("reqs.i = %v, want 0", reqs.i)
+	if i := reqs.Value(); i != 0 {
+		t.Errorf("reqs.Value() = %v, want 0", i)
 	}
 	if reqs != Get("requests").(*Int) {
 		t.Errorf("Get() failed.")
@@ -45,8 +49,8 @@
 
 	reqs.Add(1)
 	reqs.Add(3)
-	if reqs.i != 4 {
-		t.Errorf("reqs.i = %v, want 4", reqs.i)
+	if i := reqs.Value(); i != 4 {
+		t.Errorf("reqs.Value() = %v, want 4", i)
 	}
 
 	if s := reqs.String(); s != "4" {
@@ -54,12 +58,8 @@
 	}
 
 	reqs.Set(-2)
-	if reqs.i != -2 {
-		t.Errorf("reqs.i = %v, want -2", reqs.i)
-	}
-
-	if v, want := reqs.Value(), int64(-2); v != want {
-		t.Errorf("reqs.Value() = %q, want %q", v, want)
+	if i := reqs.Value(); i != -2 {
+		t.Errorf("reqs.Value() = %v, want -2", i)
 	}
 }
 
@@ -132,27 +132,22 @@
 func TestString(t *testing.T) {
 	RemoveAll()
 	name := NewString("my-name")
-	if name.s != "" {
-		t.Errorf("name.s = %q, want \"\"", name.s)
+	if s := name.Value(); s != "" {
+		t.Errorf(`NewString("my-name").Value() = %q, want ""`, s)
 	}
 
 	name.Set("Mike")
-	if name.s != "Mike" {
-		t.Errorf("name.s = %q, want \"Mike\"", name.s)
-	}
-
 	if s, want := name.String(), `"Mike"`; s != want {
-		t.Errorf("from %q, name.String() = %q, want %q", name.s, s, want)
+		t.Errorf(`after name.Set("Mike"), name.String() = %q, want %q`, s, want)
 	}
-
 	if s, want := name.Value(), "Mike"; s != want {
-		t.Errorf("from %q, name.Value() = %q, want %q", name.s, s, want)
+		t.Errorf(`after name.Set("Mike"), name.Value() = %q, want %q`, s, want)
 	}
 
 	// Make sure we produce safe JSON output.
-	name.Set(`<`)
+	name.Set("<")
 	if s, want := name.String(), "\"\\u003c\""; s != want {
-		t.Errorf("from %q, name.String() = %q, want %q", name.s, s, want)
+		t.Errorf(`after name.Set("<"), name.String() = %q, want %q`, s, want)
 	}
 }
 
@@ -174,13 +169,13 @@
 	colors.Add("red", 2)
 	colors.Add("blue", 4)
 	colors.AddFloat(`green "midori"`, 4.125)
-	if x := colors.m["red"].(*Int).i; x != 3 {
+	if x := colors.Get("red").(*Int).Value(); x != 3 {
 		t.Errorf("colors.m[\"red\"] = %v, want 3", x)
 	}
-	if x := colors.m["blue"].(*Int).i; x != 4 {
+	if x := colors.Get("blue").(*Int).Value(); x != 4 {
 		t.Errorf("colors.m[\"blue\"] = %v, want 4", x)
 	}
-	if x := colors.m[`green "midori"`].(*Float).Value(); x != 4.125 {
+	if x := colors.Get(`green "midori"`).(*Float).Value(); x != 4.125 {
 		t.Errorf("colors.m[`green \"midori\"] = %v, want 4.125", x)
 	}
 
@@ -218,24 +213,117 @@
 	})
 }
 
-func BenchmarkMapAddSame(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		m := new(Map).Init()
-		m.Add("red", 1)
-		m.Add("red", 1)
-		m.Add("red", 1)
-		m.Add("red", 1)
+func BenchmarkMapSetDifferent(b *testing.B) {
+	procKeys := make([][]string, runtime.GOMAXPROCS(0))
+	for i := range procKeys {
+		keys := make([]string, 4)
+		for j := range keys {
+			keys[j] = fmt.Sprint(i, j)
+		}
+		procKeys[i] = keys
 	}
+
+	m := new(Map).Init()
+	v := new(Int)
+	b.ResetTimer()
+
+	var n int32
+	b.RunParallel(func(pb *testing.PB) {
+		i := int(atomic.AddInt32(&n, 1)-1) % len(procKeys)
+		keys := procKeys[i]
+
+		for pb.Next() {
+			for _, k := range keys {
+				m.Set(k, v)
+			}
+		}
+	})
+}
+
+func BenchmarkMapSetString(b *testing.B) {
+	m := new(Map).Init()
+
+	v := new(String)
+	v.Set("Hello, !")
+
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			m.Set("red", v)
+		}
+	})
+}
+
+func BenchmarkMapAddSame(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			m := new(Map).Init()
+			m.Add("red", 1)
+			m.Add("red", 1)
+			m.Add("red", 1)
+			m.Add("red", 1)
+		}
+	})
 }
 
 func BenchmarkMapAddDifferent(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		m := new(Map).Init()
-		m.Add("red", 1)
-		m.Add("blue", 1)
-		m.Add("green", 1)
-		m.Add("yellow", 1)
+	procKeys := make([][]string, runtime.GOMAXPROCS(0))
+	for i := range procKeys {
+		keys := make([]string, 4)
+		for j := range keys {
+			keys[j] = fmt.Sprint(i, j)
+		}
+		procKeys[i] = keys
 	}
+
+	b.ResetTimer()
+
+	var n int32
+	b.RunParallel(func(pb *testing.PB) {
+		i := int(atomic.AddInt32(&n, 1)-1) % len(procKeys)
+		keys := procKeys[i]
+
+		for pb.Next() {
+			m := new(Map).Init()
+			for _, k := range keys {
+				m.Add(k, 1)
+			}
+		}
+	})
+}
+
+func BenchmarkMapAddSameSteadyState(b *testing.B) {
+	m := new(Map).Init()
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			m.Add("red", 1)
+		}
+	})
+}
+
+func BenchmarkMapAddDifferentSteadyState(b *testing.B) {
+	procKeys := make([][]string, runtime.GOMAXPROCS(0))
+	for i := range procKeys {
+		keys := make([]string, 4)
+		for j := range keys {
+			keys[j] = fmt.Sprint(i, j)
+		}
+		procKeys[i] = keys
+	}
+
+	m := new(Map).Init()
+	b.ResetTimer()
+
+	var n int32
+	b.RunParallel(func(pb *testing.PB) {
+		i := int(atomic.AddInt32(&n, 1)-1) % len(procKeys)
+		keys := procKeys[i]
+
+		for pb.Next() {
+			for _, k := range keys {
+				m.Add(k, 1)
+			}
+		}
+	})
 }
 
 func TestFunc(t *testing.T) {
diff --git a/libgo/go/flag/flag.go b/libgo/go/flag/flag.go
index bbbc55a..b166c57 100644
--- a/libgo/go/flag/flag.go
+++ b/libgo/go/flag/flag.go
@@ -114,7 +114,7 @@
 }
 
 func (i *intValue) Set(s string) error {
-	v, err := strconv.ParseInt(s, 0, 64)
+	v, err := strconv.ParseInt(s, 0, strconv.IntSize)
 	*i = intValue(v)
 	return err
 }
@@ -150,7 +150,7 @@
 }
 
 func (i *uintValue) Set(s string) error {
-	v, err := strconv.ParseUint(s, 0, 64)
+	v, err := strconv.ParseUint(s, 0, strconv.IntSize)
 	*i = uintValue(v)
 	return err
 }
diff --git a/libgo/go/flag/flag_test.go b/libgo/go/flag/flag_test.go
index e2319ec..02da2c7 100644
--- a/libgo/go/flag/flag_test.go
+++ b/libgo/go/flag/flag_test.go
@@ -10,6 +10,7 @@
 	"fmt"
 	"os"
 	"sort"
+	"strconv"
 	"strings"
 	"testing"
 	"time"
@@ -415,3 +416,19 @@
 		t.Errorf("got %q want %q\n", got, defaultOutput)
 	}
 }
+
+// Issue 19230: validate range of Int and Uint flag values.
+func TestIntFlagOverflow(t *testing.T) {
+	if strconv.IntSize != 32 {
+		return
+	}
+	ResetForTesting(nil)
+	Int("i", 0, "")
+	Uint("u", 0, "")
+	if err := Set("i", "2147483648"); err == nil {
+		t.Error("unexpected success setting Int")
+	}
+	if err := Set("u", "4294967296"); err == nil {
+		t.Error("unexpected success setting Uint")
+	}
+}
diff --git a/libgo/go/fmt/doc.go b/libgo/go/fmt/doc.go
index a2faecb..014ba06 100644
--- a/libgo/go/fmt/doc.go
+++ b/libgo/go/fmt/doc.go
@@ -38,7 +38,7 @@
 		%E	scientific notation, e.g. -1.234456E+78
 		%f	decimal point but no exponent, e.g. 123.456
 		%F	synonym for %f
-		%g	%e for large exponents, %f otherwise
+		%g	%e for large exponents, %f otherwise. Precision is discussed below.
 		%G	%E for large exponents, %F otherwise
 	String and slice of bytes (treated equivalently with these verbs):
 		%s	the uninterpreted bytes of the string or slice
@@ -94,7 +94,7 @@
 	precision sets the number of places after the decimal, if appropriate,
 	except that for %g/%G precision sets the total number of significant
 	digits. For example, given 12.345 the format %6.3f prints 12.345 while
-	%.3g prints 12.3. The default precision for %e and %f is 6; for %g it
+	%.3g prints 12.3. The default precision for %e, %f and %#g is 6; for %g it
 	is the smallest number of digits necessary to identify the value uniquely.
 
 	For complex numbers, the width and precision apply to the two
@@ -109,6 +109,8 @@
 			0X for hex (%#X); suppress 0x for %p (%#p);
 			for %q, print a raw (backquoted) string if strconv.CanBackquote
 			returns true;
+			always print a decimal point for %e, %E, %f, %F, %g and %G;
+			do not remove trailing zeros for %g and %G;
 			write e.g. U+0078 'x' if the character is printable for %U (%#U).
 		' '	(space) leave a space for elided sign in numbers (% d);
 			put spaces between bytes printing strings or slices in hex (% x, % X)
@@ -190,9 +192,9 @@
 	For example,
 		fmt.Sprintf("%[2]d %[1]d\n", 11, 22)
 	will yield "22 11", while
-		fmt.Sprintf("%[3]*.[2]*[1]f", 12.0, 2, 6),
+		fmt.Sprintf("%[3]*.[2]*[1]f", 12.0, 2, 6)
 	equivalent to
-		fmt.Sprintf("%6.2f", 12.0),
+		fmt.Sprintf("%6.2f", 12.0)
 	will yield " 12.00". Because an explicit index affects subsequent verbs,
 	this notation can be used to print the same values multiple times
 	by resetting the index for the first argument to be repeated:
diff --git a/libgo/go/fmt/fmt_test.go b/libgo/go/fmt/fmt_test.go
index ce00456..9e6fcfa 100644
--- a/libgo/go/fmt/fmt_test.go
+++ b/libgo/go/fmt/fmt_test.go
@@ -416,6 +416,32 @@
 	{"% .3g", 1.0, " 1"},
 	{"%b", float32(1.0), "8388608p-23"},
 	{"%b", 1.0, "4503599627370496p-52"},
+	// Test sharp flag used with floats.
+	{"%#g", 1e-323, "1.00000e-323"},
+	{"%#g", -1.0, "-1.00000"},
+	{"%#g", 1.1, "1.10000"},
+	{"%#g", 123456.0, "123456."},
+	{"%#g", 1234567.0, "1.234567e+06"},
+	{"%#g", 1230000.0, "1.23000e+06"},
+	{"%#g", 1000000.0, "1.00000e+06"},
+	{"%#.0f", 1.0, "1."},
+	{"%#.0e", 1.0, "1.e+00"},
+	{"%#.0g", 1.0, "1."},
+	{"%#.0g", 1100000.0, "1.e+06"},
+	{"%#.4f", 1.0, "1.0000"},
+	{"%#.4e", 1.0, "1.0000e+00"},
+	{"%#.4g", 1.0, "1.000"},
+	{"%#.4g", 100000.0, "1.000e+05"},
+	{"%#.0f", 123.0, "123."},
+	{"%#.0e", 123.0, "1.e+02"},
+	{"%#.0g", 123.0, "1.e+02"},
+	{"%#.4f", 123.0, "123.0000"},
+	{"%#.4e", 123.0, "1.2300e+02"},
+	{"%#.4g", 123.0, "123.0"},
+	{"%#.4g", 123000.0, "1.230e+05"},
+	{"%#9.4g", 1.0, "    1.000"},
+	// The sharp flag has no effect for binary float format.
+	{"%#b", 1.0, "4503599627370496p-52"},
 	// Precision has no effect for binary float format.
 	{"%.4b", float32(1.0), "8388608p-23"},
 	{"%.4b", -1.0, "-4503599627370496p-52"},
@@ -466,8 +492,24 @@
 	{"% .3E", -1 - 2i, "(-1.000E+00-2.000E+00i)"},
 	{"%+.3g", 1 + 2i, "(+1+2i)"},
 	{"%+.3g", complex64(1 + 2i), "(+1+2i)"},
+	{"%#g", 1 + 2i, "(1.00000+2.00000i)"},
+	{"%#g", 123456 + 789012i, "(123456.+789012.i)"},
+	{"%#g", 1e-10i, "(0.00000+1.00000e-10i)"},
+	{"%#g", -1e10 - 1.11e100i, "(-1.00000e+10-1.11000e+100i)"},
+	{"%#.0f", 1.23 + 1.0i, "(1.+1.i)"},
+	{"%#.0e", 1.23 + 1.0i, "(1.e+00+1.e+00i)"},
+	{"%#.0g", 1.23 + 1.0i, "(1.+1.i)"},
+	{"%#.0g", 0 + 100000i, "(0.+1.e+05i)"},
+	{"%#.0g", 1230000 + 0i, "(1.e+06+0.i)"},
+	{"%#.4f", 1 + 1.23i, "(1.0000+1.2300i)"},
+	{"%#.4e", 123 + 1i, "(1.2300e+02+1.0000e+00i)"},
+	{"%#.4g", 123 + 1.23i, "(123.0+1.230i)"},
+	{"%#12.5g", 0 + 100000i, "(      0.0000 +1.0000e+05i)"},
+	{"%#12.5g", 1230000 - 0i, "(  1.2300e+06     +0.0000i)"},
 	{"%b", 1 + 2i, "(4503599627370496p-52+4503599627370496p-51i)"},
 	{"%b", complex64(1 + 2i), "(8388608p-23+8388608p-22i)"},
+	// The sharp flag has no effect for binary complex format.
+	{"%#b", 1 + 2i, "(4503599627370496p-52+4503599627370496p-51i)"},
 	// Precision has no effect for binary complex format.
 	{"%.4b", 1 + 2i, "(4503599627370496p-52+4503599627370496p-51i)"},
 	{"%.4b", complex64(1 + 2i), "(8388608p-23+8388608p-22i)"},
diff --git a/libgo/go/fmt/format.go b/libgo/go/fmt/format.go
index f770483..d4b92f8 100644
--- a/libgo/go/fmt/format.go
+++ b/libgo/go/fmt/format.go
@@ -480,6 +480,46 @@
 		f.zero = oldZero
 		return
 	}
+	// The sharp flag forces printing a decimal point for non-binary formats
+	// and retains trailing zeros, which we may need to restore.
+	if f.sharp && verb != 'b' {
+		digits := 0
+		switch verb {
+		case 'v', 'g', 'G':
+			digits = prec
+			// If no precision is set explicitly use a precision of 6.
+			if digits == -1 {
+				digits = 6
+			}
+		}
+
+		// Buffer pre-allocated with enough room for
+		// exponent notations of the form "e+123".
+		var tailBuf [5]byte
+		tail := tailBuf[:0]
+
+		hasDecimalPoint := false
+		// Starting from i = 1 to skip sign at num[0].
+		for i := 1; i < len(num); i++ {
+			switch num[i] {
+			case '.':
+				hasDecimalPoint = true
+			case 'e', 'E':
+				tail = append(tail, num[i:]...)
+				num = num[:i]
+			default:
+				digits--
+			}
+		}
+		if !hasDecimalPoint {
+			num = append(num, '.')
+		}
+		for digits > 0 {
+			num = append(num, '0')
+			digits--
+		}
+		num = append(num, tail...)
+	}
 	// We want a sign if asked for and if the sign is not positive.
 	if f.plus || num[0] != '+' {
 		// If we're zero padding to the left we want the sign before the leading zeros.
diff --git a/libgo/go/fmt/print.go b/libgo/go/fmt/print.go
index a7ef2e5..2bd88f9 100644
--- a/libgo/go/fmt/print.go
+++ b/libgo/go/fmt/print.go
@@ -684,8 +684,6 @@
 	}
 }
 
-var byteType = reflect.TypeOf(byte(0))
-
 // printValue is similar to printArg but starts with a reflect value, not an interface{} value.
 // It does not handle 'p' and 'T' verbs because these should have been already handled by printArg.
 func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
diff --git a/libgo/go/go/ast/ast.go b/libgo/go/go/ast/ast.go
index a197b5a..9ab7b1e 100644
--- a/libgo/go/go/ast/ast.go
+++ b/libgo/go/go/ast/ast.go
@@ -848,6 +848,7 @@
 	TypeSpec struct {
 		Doc     *CommentGroup // associated documentation; or nil
 		Name    *Ident        // type name
+		Assign  token.Pos     // position of '=', if any
 		Type    Expr          // *Ident, *ParenExpr, *SelectorExpr, *StarExpr, or any of the *XxxTypes
 		Comment *CommentGroup // line comments; or nil
 	}
@@ -926,7 +927,7 @@
 		Recv *FieldList    // receiver (methods); or nil (functions)
 		Name *Ident        // function/method name
 		Type *FuncType     // function signature: parameters, results, and position of "func" keyword
-		Body *BlockStmt    // function body; or nil (forward declaration)
+		Body *BlockStmt    // function body; or nil for external (non-Go) function
 	}
 )
 
@@ -966,6 +967,19 @@
 // appearance, including the comments that are pointed to from other nodes
 // via Doc and Comment fields.
 //
+// For correct printing of source code containing comments (using packages
+// go/format and go/printer), special care must be taken to update comments
+// when a File's syntax tree is modified: For printing, comments are interspersed
+// between tokens based on their position. If syntax tree nodes are
+// removed or moved, relevant comments in their vicinity must also be removed
+// (from the File.Comments list) or moved accordingly (by updating their
+// positions). A CommentMap may be used to facilitate some of these operations.
+//
+// Whether and how a comment is associated with a node depends on the
+// interpretation of the syntax tree by the manipulating program: Except for Doc
+// and Comment comments directly associated with nodes, the remaining comments
+// are "free-floating" (see also issues #18593, #20744).
+//
 type File struct {
 	Doc        *CommentGroup   // associated documentation; or nil
 	Package    token.Pos       // position of "package" keyword
diff --git a/libgo/go/go/build/build.go b/libgo/go/go/build/build.go
index cce5d48..5aa32d0 100644
--- a/libgo/go/go/build/build.go
+++ b/libgo/go/go/build/build.go
@@ -155,6 +155,7 @@
 	return hasSubdir(rootSym, dirSym)
 }
 
+// hasSubdir reports if dir is within root by performing lexical analysis only.
 func hasSubdir(root, dir string) (rel string, ok bool) {
 	const sep = string(filepath.Separator)
 	root = filepath.Clean(root)
@@ -290,7 +291,8 @@
 	// in all releases >= Go 1.x. Code that requires Go 1.x or later should
 	// say "+build go1.x", and code that should only be built before Go 1.x
 	// (perhaps it is the stub to use in that case) should say "+build !go1.x".
-	c.ReleaseTags = []string{"go1.1", "go1.2", "go1.3", "go1.4", "go1.5", "go1.6", "go1.7", "go1.8"}
+	// NOTE: If you add to this list, also update the doc comment in doc.go.
+	c.ReleaseTags = []string{"go1.1", "go1.2", "go1.3", "go1.4", "go1.5", "go1.6", "go1.7", "go1.8", "go1.9"}
 
 	env := os.Getenv("CGO_ENABLED")
 	// No defaultCGO_ENABLED in gccgo.
@@ -529,6 +531,7 @@
 		if !ctxt.isAbsPath(path) {
 			p.Dir = ctxt.joinPath(srcDir, path)
 		}
+		// p.Dir directory may or may not exist. Gather partial information first, check if it exists later.
 		// Determine canonical import path, if any.
 		// Exclude results where the import path would include /testdata/.
 		inTestdata := func(sub string) bool {
@@ -683,6 +686,16 @@
 		}
 	}
 
+	// If it's a local import path, by the time we get here, we still haven't checked
+	// that p.Dir directory exists. This is the right time to do that check.
+	// We can't do it earlier, because we want to gather partial information for the
+	// non-nil *Package returned when an error occurs.
+	// We need to do this before we return early on FindOnly flag.
+	if IsLocalImport(path) && !ctxt.isDir(p.Dir) {
+		// package was not found
+		return p, fmt.Errorf("cannot find package %q in:\n\t%s", path, p.Dir)
+	}
+
 	if mode&FindOnly != 0 {
 		return p, pkgerr
 	}
@@ -718,7 +731,7 @@
 			p.InvalidGoFiles = append(p.InvalidGoFiles, name)
 		}
 
-		match, data, filename, err := ctxt.matchFile(p.Dir, name, true, allTags, &p.BinaryOnly)
+		match, data, filename, err := ctxt.matchFile(p.Dir, name, allTags, &p.BinaryOnly)
 		if err != nil {
 			badFile(err)
 			continue
@@ -1032,19 +1045,19 @@
 // MatchFile considers the name of the file and may use ctxt.OpenFile to
 // read some or all of the file's content.
 func (ctxt *Context) MatchFile(dir, name string) (match bool, err error) {
-	match, _, _, err = ctxt.matchFile(dir, name, false, nil, nil)
+	match, _, _, err = ctxt.matchFile(dir, name, nil, nil)
 	return
 }
 
 // matchFile determines whether the file with the given name in the given directory
 // should be included in the package being constructed.
 // It returns the data read from the file.
-// If returnImports is true and name denotes a Go program, matchFile reads
-// until the end of the imports (and returns that data) even though it only
-// considers text until the first non-comment.
+// If name denotes a Go program, matchFile reads until the end of the
+// imports (and returns that data) even though it only considers text
+// until the first non-comment.
 // If allTags is non-nil, matchFile records any encountered build tag
 // by setting allTags[tag] = true.
-func (ctxt *Context) matchFile(dir, name string, returnImports bool, allTags map[string]bool, binaryOnly *bool) (match bool, data []byte, filename string, err error) {
+func (ctxt *Context) matchFile(dir, name string, allTags map[string]bool, binaryOnly *bool) (match bool, data []byte, filename string, err error) {
 	if strings.HasPrefix(name, "_") ||
 		strings.HasPrefix(name, ".") {
 		return
@@ -1271,6 +1284,12 @@
 		}
 
 		switch verb {
+		case "CFLAGS", "CPPFLAGS", "CXXFLAGS", "FFLAGS", "LDFLAGS":
+			// Change relative paths to absolute.
+			ctxt.makePathsAbsolute(args, di.Dir)
+		}
+
+		switch verb {
 		case "CFLAGS":
 			di.CgoCFLAGS = append(di.CgoCFLAGS, args...)
 		case "CPPFLAGS":
@@ -1298,40 +1317,63 @@
 	// to "/" before starting (eg: on windows).
 	srcdir = filepath.ToSlash(srcdir)
 
-	// Spaces are tolerated in ${SRCDIR}, but not anywhere else.
 	chunks := strings.Split(str, "${SRCDIR}")
 	if len(chunks) < 2 {
-		return str, safeCgoName(str, false)
+		return str, safeCgoName(str)
 	}
 	ok := true
 	for _, chunk := range chunks {
-		ok = ok && (chunk == "" || safeCgoName(chunk, false))
+		ok = ok && (chunk == "" || safeCgoName(chunk))
 	}
-	ok = ok && (srcdir == "" || safeCgoName(srcdir, true))
+	ok = ok && (srcdir == "" || safeCgoName(srcdir))
 	res := strings.Join(chunks, srcdir)
 	return res, ok && res != ""
 }
 
+// makePathsAbsolute looks for compiler options that take paths and
+// makes them absolute. We do this because through the 1.8 release we
+// ran the compiler in the package directory, so any relative -I or -L
+// options would be relative to that directory. In 1.9 we changed to
+// running the compiler in the build directory, to get consistent
+// build results (issue #19964). To keep builds working, we change any
+// relative -I or -L options to be absolute.
+//
+// Using filepath.IsAbs and filepath.Join here means the results will be
+// different on different systems, but that's OK: -I and -L options are
+// inherently system-dependent.
+func (ctxt *Context) makePathsAbsolute(args []string, srcDir string) {
+	nextPath := false
+	for i, arg := range args {
+		if nextPath {
+			if !filepath.IsAbs(arg) {
+				args[i] = filepath.Join(srcDir, arg)
+			}
+			nextPath = false
+		} else if strings.HasPrefix(arg, "-I") || strings.HasPrefix(arg, "-L") {
+			if len(arg) == 2 {
+				nextPath = true
+			} else {
+				if !filepath.IsAbs(arg[2:]) {
+					args[i] = arg[:2] + filepath.Join(srcDir, arg[2:])
+				}
+			}
+		}
+	}
+}
+
 // NOTE: $ is not safe for the shell, but it is allowed here because of linker options like -Wl,$ORIGIN.
 // We never pass these arguments to a shell (just to programs we construct argv for), so this should be okay.
 // See golang.org/issue/6038.
 // The @ is for OS X. See golang.org/issue/13720.
 // The % is for Jenkins. See golang.org/issue/16959.
-const safeString = "+-.,/0123456789=ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz:$@%"
-const safeSpaces = " "
+const safeString = "+-.,/0123456789=ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz:$@% "
 
-var safeBytes = []byte(safeSpaces + safeString)
-
-func safeCgoName(s string, spaces bool) bool {
+func safeCgoName(s string) bool {
 	if s == "" {
 		return false
 	}
-	safe := safeBytes
-	if !spaces {
-		safe = safe[len(safeSpaces):]
-	}
 	for i := 0; i < len(s); i++ {
-		if c := s[i]; c < utf8.RuneSelf && bytes.IndexByte(safe, c) < 0 {
+		if c := s[i]; c < utf8.RuneSelf && strings.IndexByte(safeString, c) < 0 {
 			return false
 		}
 	}
diff --git a/libgo/go/go/build/build_test.go b/libgo/go/go/build/build_test.go
index 2e2ff84..38e2e8a 100644
--- a/libgo/go/go/build/build_test.go
+++ b/libgo/go/go/build/build_test.go
@@ -287,9 +287,11 @@
 		{"-I${SRCDIR}/../include", "/projects/src/issue 11868", "-I/projects/src/issue 11868/../include", true},
 		{"-I${SRCDIR}", "wtf$@%", "-Iwtf$@%", true},
 		{"-X${SRCDIR}/1,${SRCDIR}/2", "/projects/src/issue 11868", "-X/projects/src/issue 11868/1,/projects/src/issue 11868/2", true},
-		{"-I/tmp -I/tmp", "/tmp2", "-I/tmp -I/tmp", false},
+		{"-I/tmp -I/tmp", "/tmp2", "-I/tmp -I/tmp", true},
 		{"-I/tmp", "/tmp/[0]", "-I/tmp", true},
 		{"-I${SRCDIR}/dir", "/tmp/[0]", "-I/tmp/[0]/dir", false},
+		{"-I${SRCDIR}/dir", "/tmp/go go", "-I/tmp/go go/dir", true},
+		{"-I${SRCDIR}/dir dir", "/tmp/go", "-I/tmp/go/dir dir", true},
 	}
 	for _, test := range tests {
 		output, ok := expandSrcDir(test.input, test.srcdir)
@@ -302,6 +304,40 @@
 	}
 }
 
+// Want to get a "cannot find package" error when directory for package does not exist.
+// There should be valid partial information in the returned non-nil *Package.
+func TestImportDirNotExist(t *testing.T) {
+	testenv.MustHaveGoBuild(t) // really must just have source
+	ctxt := Default
+	ctxt.GOPATH = ""
+
+	tests := []struct {
+		label        string
+		path, srcDir string
+		mode         ImportMode
+	}{
+		{"Import(full, 0)", "go/build/doesnotexist", "", 0},
+		{"Import(local, 0)", "./doesnotexist", filepath.Join(ctxt.GOROOT, "src/go/build"), 0},
+		{"Import(full, FindOnly)", "go/build/doesnotexist", "", FindOnly},
+		{"Import(local, FindOnly)", "./doesnotexist", filepath.Join(ctxt.GOROOT, "src/go/build"), FindOnly},
+	}
+	for _, test := range tests {
+		p, err := ctxt.Import(test.path, test.srcDir, test.mode)
+		if err == nil || !strings.HasPrefix(err.Error(), "cannot find package") {
+			t.Errorf(`%s got error: %q, want "cannot find package" error`, test.label, err)
+		}
+		// If an error occurs, build.Import is documented to return
+		// a non-nil *Package containing partial information.
+		if p == nil {
+			t.Fatalf(`%s got nil p, want non-nil *Package`, test.label)
+		}
+		// Verify partial information in p.
+		if p.ImportPath != "go/build/doesnotexist" {
+			t.Errorf(`%s got p.ImportPath: %q, want "go/build/doesnotexist"`, test.label, p.ImportPath)
+		}
+	}
+}
+
 func TestImportVendor(t *testing.T) {
 	testenv.MustHaveGoBuild(t) // really must just have source
 	ctxt := Default
diff --git a/libgo/go/go/build/deps_test.go b/libgo/go/go/build/deps_test.go
index 147eaf6..87abfba 100644
--- a/libgo/go/go/build/deps_test.go
+++ b/libgo/go/go/build/deps_test.go
@@ -43,6 +43,7 @@
 	"sync":                    {"internal/race", "runtime", "sync/atomic", "unsafe"},
 	"sync/atomic":             {"unsafe"},
 	"unsafe":                  {},
+	"internal/cpu":            {"runtime"},
 
 	"L0": {
 		"errors",
@@ -52,11 +53,13 @@
 		"sync",
 		"sync/atomic",
 		"unsafe",
+		"internal/cpu",
 	},
 
 	// L1 adds simple functions and strings processing,
 	// but not Unicode tables.
-	"math":          {"unsafe"},
+	"math":          {"internal/cpu", "unsafe"},
+	"math/bits":     {},
 	"math/cmplx":    {"math"},
 	"math/rand":     {"L0", "math"},
 	"strconv":       {"L0", "unicode/utf8", "math"},
@@ -66,6 +69,7 @@
 	"L1": {
 		"L0",
 		"math",
+		"math/bits",
 		"math/cmplx",
 		"math/rand",
 		"sort",
@@ -150,7 +154,8 @@
 		"syscall",
 	},
 
-	"os":            {"L1", "os", "syscall", "time", "internal/syscall/windows"},
+	"internal/poll": {"L0", "internal/race", "syscall", "time", "unicode/utf16", "unicode/utf8"},
+	"os":            {"L1", "os", "syscall", "time", "internal/poll", "internal/syscall/windows"},
 	"path/filepath": {"L2", "os", "syscall"},
 	"io/ioutil":     {"L2", "os", "path/filepath", "time"},
 	"os/exec":       {"L2", "os", "context", "path/filepath", "syscall"},
@@ -171,17 +176,16 @@
 	"log": {"L1", "os", "fmt", "time"},
 
 	// Packages used by testing must be low-level (L2+fmt).
-	"regexp":                            {"L2", "regexp/syntax"},
-	"regexp/syntax":                     {"L2"},
-	"runtime/debug":                     {"L2", "fmt", "io/ioutil", "os", "time"},
-	"runtime/pprof/internal/protopprof": {"L2", "fmt", "internal/pprof/profile", "os", "time"},
-	"runtime/pprof":                     {"L2", "fmt", "internal/pprof/profile", "os", "runtime/pprof/internal/protopprof", "text/tabwriter", "time"},
-	"runtime/trace":                     {"L0"},
-	"text/tabwriter":                    {"L2"},
+	"regexp":         {"L2", "regexp/syntax"},
+	"regexp/syntax":  {"L2"},
+	"runtime/debug":  {"L2", "fmt", "io/ioutil", "os", "time"},
+	"runtime/pprof":  {"L2", "compress/gzip", "context", "encoding/binary", "fmt", "io/ioutil", "os", "text/tabwriter", "time"},
+	"runtime/trace":  {"L0"},
+	"text/tabwriter": {"L2"},
 
 	"testing":          {"L2", "flag", "fmt", "internal/race", "os", "runtime/debug", "runtime/pprof", "runtime/trace", "time"},
 	"testing/iotest":   {"L2", "log"},
-	"testing/quick":    {"L2", "flag", "fmt", "reflect"},
+	"testing/quick":    {"L2", "flag", "fmt", "reflect", "time"},
 	"internal/testenv": {"L2", "OS", "flag", "testing", "syscall"},
 
 	// L4 is defined as L3+fmt+log+time, because in general once
@@ -215,59 +219,60 @@
 
 	// Go type checking.
 	"go/constant":               {"L4", "go/token", "math/big"},
-	"go/importer":               {"L4", "go/internal/gcimporter", "go/internal/gccgoimporter", "go/types"},
+	"go/importer":               {"L4", "go/build", "go/internal/gccgoimporter", "go/internal/gcimporter", "go/internal/srcimporter", "go/token", "go/types"},
 	"go/internal/gcimporter":    {"L4", "OS", "go/build", "go/constant", "go/token", "go/types", "text/scanner"},
 	"go/internal/gccgoimporter": {"L4", "OS", "debug/elf", "go/constant", "go/token", "go/types", "text/scanner"},
+	"go/internal/srcimporter":   {"L4", "fmt", "go/ast", "go/build", "go/parser", "go/token", "go/types", "path/filepath"},
 	"go/types":                  {"L4", "GOPARSER", "container/heap", "go/constant"},
 
 	// One of a kind.
-	"archive/tar":               {"L4", "OS", "syscall"},
-	"archive/zip":               {"L4", "OS", "compress/flate"},
-	"container/heap":            {"sort"},
-	"compress/bzip2":            {"L4"},
-	"compress/flate":            {"L4"},
-	"compress/gzip":             {"L4", "compress/flate"},
-	"compress/lzw":              {"L4"},
-	"compress/zlib":             {"L4", "compress/flate"},
-	"context":                   {"errors", "fmt", "reflect", "sync", "time"},
-	"database/sql":              {"L4", "container/list", "context", "database/sql/driver", "database/sql/internal"},
-	"database/sql/driver":       {"L4", "context", "time", "database/sql/internal"},
-	"debug/dwarf":               {"L4"},
-	"debug/elf":                 {"L4", "OS", "debug/dwarf", "compress/zlib"},
-	"debug/gosym":               {"L4"},
-	"debug/macho":               {"L4", "OS", "debug/dwarf"},
-	"debug/pe":                  {"L4", "OS", "debug/dwarf"},
-	"debug/plan9obj":            {"L4", "OS"},
-	"encoding":                  {"L4"},
-	"encoding/ascii85":          {"L4"},
-	"encoding/asn1":             {"L4", "math/big"},
-	"encoding/csv":              {"L4"},
-	"encoding/gob":              {"L4", "OS", "encoding"},
-	"encoding/hex":              {"L4"},
-	"encoding/json":             {"L4", "encoding"},
-	"encoding/pem":              {"L4"},
-	"encoding/xml":              {"L4", "encoding"},
-	"flag":                      {"L4", "OS"},
-	"go/build":                  {"L4", "OS", "GOPARSER"},
-	"html":                      {"L4"},
-	"image/draw":                {"L4", "image/internal/imageutil"},
-	"image/gif":                 {"L4", "compress/lzw", "image/color/palette", "image/draw"},
-	"image/internal/imageutil":  {"L4"},
-	"image/jpeg":                {"L4", "image/internal/imageutil"},
-	"image/png":                 {"L4", "compress/zlib"},
-	"index/suffixarray":         {"L4", "regexp"},
-	"internal/singleflight":     {"sync"},
-	"internal/trace":            {"L4", "OS"},
-	"internal/pprof/profile":    {"L4", "OS", "compress/gzip", "regexp"},
-	"math/big":                  {"L4"},
-	"mime":                      {"L4", "OS", "syscall", "internal/syscall/windows/registry"},
-	"mime/quotedprintable":      {"L4"},
-	"net/internal/socktest":     {"L4", "OS", "syscall"},
-	"net/url":                   {"L4"},
-	"plugin":                    {"L0", "OS", "CGO"},
-	"testing/internal/testdeps": {"L4", "runtime/pprof", "regexp"},
-	"text/scanner":              {"L4", "OS"},
-	"text/template/parse":       {"L4"},
+	"archive/tar":              {"L4", "OS", "syscall"},
+	"archive/zip":              {"L4", "OS", "compress/flate"},
+	"container/heap":           {"sort"},
+	"compress/bzip2":           {"L4"},
+	"compress/flate":           {"L4"},
+	"compress/gzip":            {"L4", "compress/flate"},
+	"compress/lzw":             {"L4"},
+	"compress/zlib":            {"L4", "compress/flate"},
+	"context":                  {"errors", "fmt", "reflect", "sync", "time"},
+	"database/sql":             {"L4", "container/list", "context", "database/sql/driver", "database/sql/internal"},
+	"database/sql/driver":      {"L4", "context", "time", "database/sql/internal"},
+	"debug/dwarf":              {"L4"},
+	"debug/elf":                {"L4", "OS", "debug/dwarf", "compress/zlib"},
+	"debug/gosym":              {"L4"},
+	"debug/macho":              {"L4", "OS", "debug/dwarf"},
+	"debug/pe":                 {"L4", "OS", "debug/dwarf"},
+	"debug/plan9obj":           {"L4", "OS"},
+	"encoding":                 {"L4"},
+	"encoding/ascii85":         {"L4"},
+	"encoding/asn1":            {"L4", "math/big"},
+	"encoding/csv":             {"L4"},
+	"encoding/gob":             {"L4", "OS", "encoding"},
+	"encoding/hex":             {"L4"},
+	"encoding/json":            {"L4", "encoding"},
+	"encoding/pem":             {"L4"},
+	"encoding/xml":             {"L4", "encoding"},
+	"flag":                     {"L4", "OS"},
+	"go/build":                 {"L4", "OS", "GOPARSER"},
+	"html":                     {"L4"},
+	"image/draw":               {"L4", "image/internal/imageutil"},
+	"image/gif":                {"L4", "compress/lzw", "image/color/palette", "image/draw"},
+	"image/internal/imageutil": {"L4"},
+	"image/jpeg":               {"L4", "image/internal/imageutil"},
+	"image/png":                {"L4", "compress/zlib"},
+	"index/suffixarray":        {"L4", "regexp"},
+	"internal/singleflight":    {"sync"},
+	"internal/trace":           {"L4", "OS"},
+	"math/big":                 {"L4"},
+	"mime":                     {"L4", "OS", "syscall", "internal/syscall/windows/registry"},
+	"mime/quotedprintable":     {"L4"},
+	"net/internal/socktest":    {"L4", "OS", "syscall"},
+	"net/url":                  {"L4"},
+	"plugin":                   {"L0", "OS", "CGO"},
+	"runtime/pprof/internal/profile": {"L4", "OS", "compress/gzip", "regexp"},
+	"testing/internal/testdeps":      {"L4", "runtime/pprof", "regexp"},
+	"text/scanner":                   {"L4", "OS"},
+	"text/template/parse":            {"L4"},
 
 	"html/template": {
 		"L4", "OS", "encoding/json", "html", "text/template",
@@ -299,8 +304,8 @@
 	// do networking portably, it must have a small dependency set: just L0+basic os.
 	"net": {
 		"L0", "CGO",
-		"context", "math/rand", "os", "sort", "syscall", "time",
-		"internal/nettrace",
+		"context", "math/rand", "os", "reflect", "sort", "syscall", "time",
+		"internal/nettrace", "internal/poll",
 		"internal/syscall/windows", "internal/singleflight", "internal/race",
 		"golang_org/x/net/lif", "golang_org/x/net/route",
 	},
@@ -372,7 +377,7 @@
 	},
 	"crypto/x509": {
 		"L4", "CRYPTO-MATH", "OS", "CGO",
-		"crypto/x509/pkix", "encoding/pem", "encoding/hex", "net", "syscall",
+		"crypto/x509/pkix", "encoding/pem", "encoding/hex", "net", "os/user", "syscall",
 	},
 	"crypto/x509/pkix": {"L4", "CRYPTO-MATH"},
 
@@ -391,6 +396,7 @@
 		"golang_org/x/net/http2/hpack",
 		"golang_org/x/net/idna",
 		"golang_org/x/net/lex/httplex",
+		"golang_org/x/net/proxy",
 		"golang_org/x/text/unicode/norm",
 		"golang_org/x/text/width",
 		"internal/nettrace",
@@ -406,8 +412,8 @@
 	"expvar":             {"L4", "OS", "encoding/json", "net/http"},
 	"net/http/cgi":       {"L4", "NET", "OS", "crypto/tls", "net/http", "regexp"},
 	"net/http/cookiejar": {"L4", "NET", "net/http"},
-	"net/http/fcgi":      {"L4", "NET", "OS", "net/http", "net/http/cgi"},
-	"net/http/httptest":  {"L4", "NET", "OS", "crypto/tls", "flag", "net/http", "net/http/internal"},
+	"net/http/fcgi":      {"L4", "NET", "OS", "context", "net/http", "net/http/cgi"},
+	"net/http/httptest":  {"L4", "NET", "OS", "crypto/tls", "flag", "net/http", "net/http/internal", "crypto/x509"},
 	"net/http/httputil":  {"L4", "NET", "OS", "context", "net/http", "net/http/internal"},
 	"net/http/pprof":     {"L4", "OS", "html/template", "net/http", "runtime/pprof", "runtime/trace"},
 	"net/rpc":            {"L4", "NET", "encoding/gob", "html/template", "net/http"},
diff --git a/libgo/go/go/build/doc.go b/libgo/go/go/build/doc.go
index 979d047..422e1a5 100644
--- a/libgo/go/go/build/doc.go
+++ b/libgo/go/go/build/doc.go
@@ -105,6 +105,7 @@
 //	- "go1.6", from Go version 1.6 onward
 //	- "go1.7", from Go version 1.7 onward
 //	- "go1.8", from Go version 1.8 onward
+//	- "go1.9", from Go version 1.9 onward
 //	- any additional words listed in ctxt.BuildTags
 //
 // If a file's name, after stripping the extension and a possible _test suffix,
diff --git a/libgo/go/go/constant/value.go b/libgo/go/go/constant/value.go
index 7c32473..5474e73 100644
--- a/libgo/go/go/constant/value.go
+++ b/libgo/go/go/constant/value.go
@@ -205,13 +205,8 @@
 
 func vtoc(x Value) complexVal { return complexVal{x, int64Val(0)} }
 
-var (
-	minInt64 = big.NewInt(-1 << 63)
-	maxInt64 = big.NewInt(1<<63 - 1)
-)
-
 func makeInt(x *big.Int) Value {
-	if minInt64.Cmp(x) <= 0 && x.Cmp(maxInt64) <= 0 {
+	if x.IsInt64() {
 		return int64Val(x.Int64())
 	}
 	return intVal{x}
@@ -252,6 +247,13 @@
 	if f, ok := newFloat().SetString(lit); ok {
 		if smallRat(f) {
 			// ok to use rationals
+			if f.Sign() == 0 {
+				// Issue 20228: If the float underflowed to zero, parse just "0".
+				// Otherwise, lit might contain a value with a large negative exponent,
+				// such as -6e-1886451601. As a float, that will underflow to 0,
+				// but it'll take forever to parse as a Rat.
+				lit = "0"
+			}
 			r, _ := newRat().SetString(lit)
 			return ratVal{r}
 		}
@@ -413,7 +415,7 @@
 	case int64Val:
 		return uint64(x), x >= 0
 	case intVal:
-		return x.val.Uint64(), x.val.Sign() >= 0 && x.val.BitLen() <= 64
+		return x.val.Uint64(), x.val.IsUint64()
 	case unknownVal:
 		return 0, false
 	default:
diff --git a/libgo/go/go/constant/value_test.go b/libgo/go/go/constant/value_test.go
index 8a8a08e..954a0e0 100644
--- a/libgo/go/go/constant/value_test.go
+++ b/libgo/go/go/constant/value_test.go
@@ -244,7 +244,8 @@
 	{"1e9999", "1e+9999", "0x.f8d4a9da224650a8cb2959e10d985ad92adbd44c62917e608b1f24c0e1b76b6f61edffeb15c135a4b601637315f7662f325f82325422b244286a07663c9415d2p+33216"},
 	{"1e-9999", "1e-9999", "0x.83b01ba6d8c0425eec1b21e96f7742d63c2653ed0a024cf8a2f9686df578d7b07d7a83d84df6a2ec70a921d1f6cd5574893a7eda4d28ee719e13a5dce2700759p-33215"},
 	{"2.71828182845904523536028747135266249775724709369995957496696763", "2.71828", "271828182845904523536028747135266249775724709369995957496696763/100000000000000000000000000000000000000000000000000000000000000"},
-	{"0e9999999999", "0", "0"}, // issue #16176
+	{"0e9999999999", "0", "0"},   // issue #16176
+	{"-6e-1886451601", "0", "0"}, // issue #20228
 
 	// Complex
 	{"0i", "(0 + 0i)", "(0 + 0i)"},
diff --git a/libgo/go/go/doc/comment.go b/libgo/go/go/doc/comment.go
index 15e034b..4228e8c 100644
--- a/libgo/go/go/doc/comment.go
+++ b/libgo/go/go/doc/comment.go
@@ -48,12 +48,19 @@
 	identRx = `[\pL_][\pL_0-9]*`
 
 	// Regexp for URLs
-	protocol = `https?|ftp|file|gopher|mailto|news|nntp|telnet|wais|prospero`
-	hostPart = `[a-zA-Z0-9_@\-]+`
-	filePart = `[a-zA-Z0-9_?%#~&/\-+=()]+` // parentheses may not be matching; see pairedParensPrefixLen
-	urlRx    = `(` + protocol + `)://` +   // http://
-		hostPart + `([.:]` + hostPart + `)*/?` + // //www.google.com:8080/
-		filePart + `([:.,;]` + filePart + `)*`
+	// Match parens, and check in pairedParensPrefixLen for balance - see #5043
+	// Match .,:;?! within path, but not at end - see #18139, #16565
+	// This excludes some rare yet valid urls ending in common punctuation
+	// in order to allow sentences ending in URLs.
+
+	// protocol (required) e.g. http
+	protoPart = `(https?|ftp|file|gopher|mailto|nntp)`
+	// host (required) e.g. www.example.com or [::1]:8080
+	hostPart = `([a-zA-Z0-9_@\-.\[\]:]+)`
+	// path+query+fragment (optional) e.g. /path/index.html?q=foo#bar
+	pathPart = `([.,:;?!]*[a-zA-Z0-9$'()*+&#=@~_/\-\[\]%])*`
+
+	urlRx = protoPart + `://` + hostPart + pathPart
 )
 
 var matchRx = regexp.MustCompile(`(` + urlRx + `)|(` + identRx + `)`)
diff --git a/libgo/go/go/doc/comment_test.go b/libgo/go/go/doc/comment_test.go
index 76dfbea..0523ab8 100644
--- a/libgo/go/go/doc/comment_test.go
+++ b/libgo/go/go/doc/comment_test.go
@@ -150,6 +150,12 @@
 var emphasizeTests = []struct {
 	in, out string
 }{
+	{"http://[::1]:8080/foo.txt", `<a href="http://[::1]:8080/foo.txt">http://[::1]:8080/foo.txt</a>`},
+	{"before (https://www.google.com) after", `before (<a href="https://www.google.com">https://www.google.com</a>) after`},
+	{"before https://www.google.com:30/x/y/z:b::c. After", `before <a href="https://www.google.com:30/x/y/z:b::c">https://www.google.com:30/x/y/z:b::c</a>. After`},
+	{"http://www.google.com/path/:;!-/?query=%34b#093124", `<a href="http://www.google.com/path/:;!-/?query=%34b#093124">http://www.google.com/path/:;!-/?query=%34b#093124</a>`},
+	{"http://www.google.com/path/:;!-/?query=%34bar#093124", `<a href="http://www.google.com/path/:;!-/?query=%34bar#093124">http://www.google.com/path/:;!-/?query=%34bar#093124</a>`},
+	{"http://www.google.com/index.html! After", `<a href="http://www.google.com/index.html">http://www.google.com/index.html</a>! After`},
 	{"http://www.google.com/", `<a href="http://www.google.com/">http://www.google.com/</a>`},
 	{"https://www.google.com/", `<a href="https://www.google.com/">https://www.google.com/</a>`},
 	{"http://www.google.com/path.", `<a href="http://www.google.com/path">http://www.google.com/path</a>.`},
diff --git a/libgo/go/go/doc/doc_test.go b/libgo/go/go/doc/doc_test.go
index 82e6310..ad8ba53 100644
--- a/libgo/go/go/doc/doc_test.go
+++ b/libgo/go/go/doc/doc_test.go
@@ -25,7 +25,7 @@
 
 const dataDir = "testdata"
 
-var templateTxt *template.Template
+var templateTxt = readTemplate("template.txt")
 
 func readTemplate(filename string) *template.Template {
 	t := template.New(filename)
@@ -96,9 +96,6 @@
 	if err != nil {
 		t.Fatal(err)
 	}
-	if templateTxt == nil {
-		templateTxt = readTemplate("template.txt")
-	}
 
 	// test packages
 	for _, pkg := range pkgs {
diff --git a/libgo/go/go/doc/exports.go b/libgo/go/go/doc/exports.go
index 4a12b1e..da9ea1f 100644
--- a/libgo/go/go/doc/exports.go
+++ b/libgo/go/go/doc/exports.go
@@ -150,7 +150,7 @@
 	}
 }
 
-func (r *reader) filterSpec(spec ast.Spec, tok token.Token) bool {
+func (r *reader) filterSpec(spec ast.Spec) bool {
 	switch s := spec.(type) {
 	case *ast.ImportSpec:
 		// always keep imports so we can collect them
@@ -215,7 +215,7 @@
 
 	j := 0
 	for _, s := range list {
-		if r.filterSpec(s, tok) {
+		if r.filterSpec(s) {
 			list[j] = s
 			j++
 		}
diff --git a/libgo/go/go/format/internal.go b/libgo/go/go/format/internal.go
index b8b470d..4918681 100644
--- a/libgo/go/go/format/internal.go
+++ b/libgo/go/go/format/internal.go
@@ -37,14 +37,14 @@
 
 	// If this is a declaration list, make it a source file
 	// by inserting a package clause.
-	// Insert using a ;, not a newline, so that the line numbers
+	// Insert using a ';', not a newline, so that the line numbers
 	// in psrc match the ones in src.
 	psrc := append([]byte("package p;"), src...)
 	file, err = parser.ParseFile(fset, filename, psrc, parserMode)
 	if err == nil {
 		sourceAdj = func(src []byte, indent int) []byte {
 			// Remove the package clause.
-			// Gofmt has turned the ; into a \n.
+			// Gofmt has turned the ';' into a '\n'.
 			src = src[indent+len("package p\n"):]
 			return bytes.TrimSpace(src)
 		}
@@ -60,7 +60,7 @@
 	// If this is a statement list, make it a source file
 	// by inserting a package clause and turning the list
 	// into a function body. This handles expressions too.
-	// Insert using a ;, not a newline, so that the line numbers
+	// Insert using a ';', not a newline, so that the line numbers
 	// in fsrc match the ones in src. Add an extra '\n' before the '}'
 	// to make sure comments are flushed before the '}'.
 	fsrc := append(append([]byte("package p; func _() {"), src...), '\n', '\n', '}')
@@ -72,7 +72,7 @@
 				indent = 0
 			}
 			// Remove the wrapping.
-			// Gofmt has turned the ; into a \n\n.
+			// Gofmt has turned the ';' into a '\n'.
 			// There will be two non-blank lines with indent, hence 2*indent.
 			src = src[2*indent+len("package p\n\nfunc _() {"):]
 			// Remove only the "}\n" suffix: remaining whitespaces will be trimmed anyway
diff --git a/libgo/go/go/importer/importer.go b/libgo/go/go/importer/importer.go
index f655bc1..fab6518 100644
--- a/libgo/go/go/importer/importer.go
+++ b/libgo/go/go/importer/importer.go
@@ -6,8 +6,11 @@
 package importer
 
 import (
+	"go/build"
 	"go/internal/gccgoimporter"
 	"go/internal/gcimporter"
+	"go/internal/srcimporter"
+	"go/token"
 	"go/types"
 	"io"
 	"runtime"
@@ -17,22 +20,30 @@
 // a given import path, or an error if no matching package is found.
 type Lookup func(path string) (io.ReadCloser, error)
 
-// For returns an Importer for the given compiler and lookup interface,
-// or nil. Supported compilers are "gc", and "gccgo". If lookup is nil,
-// the default package lookup mechanism for the given compiler is used.
+// For returns an Importer for importing from installed packages
+// for the compilers "gc" and "gccgo", or for importing directly
+// from the source if the compiler argument is "source". In this
+// latter case, importing may fail under circumstances where the
+// exported API is not entirely defined in pure Go source code
+// (if the package API depends on cgo-defined entities, the type
+// checker won't have access to those).
+//
+// If lookup is nil, the default package lookup mechanism for the
+// given compiler is used.
+//
 // BUG(issue13847): For does not support non-nil lookup functions.
 func For(compiler string, lookup Lookup) types.Importer {
 	switch compiler {
 	case "gc":
 		if lookup != nil {
-			panic("gc importer for custom import path lookup not yet implemented")
+			panic("gc importer for custom import path lookup not supported (issue #13847).")
 		}
 
 		return make(gcimports)
 
 	case "gccgo":
 		if lookup != nil {
-			panic("gccgo importer for custom import path lookup not yet implemented")
+			panic("gccgo importer for custom import path lookup not supported (issue #13847).")
 		}
 
 		var inst gccgoimporter.GccgoInstallation
@@ -43,6 +54,13 @@
 			packages: make(map[string]*types.Package),
 			importer: inst.GetImporter(nil, nil),
 		}
+
+	case "source":
+		if lookup != nil {
+			panic("source importer for custom import path lookup not supported (issue #13847).")
+		}
+
+		return srcimporter.New(&build.Default, token.NewFileSet(), make(map[string]*types.Package))
 	}
 
 	// compiler not supported
@@ -55,7 +73,7 @@
 	return For(runtime.Compiler, nil)
 }
 
-// gc support
+// gc importer
 
 type gcimports map[string]*types.Package
 
@@ -70,7 +88,7 @@
 	return gcimporter.Import(m, path, srcDir)
 }
 
-// gccgo support
+// gccgo importer
 
 type gccgoimports struct {
 	packages map[string]*types.Package
diff --git a/libgo/go/go/internal/gccgoimporter/importer_test.go b/libgo/go/go/internal/gccgoimporter/importer_test.go
index 2b45470..4fca828 100644
--- a/libgo/go/go/internal/gccgoimporter/importer_test.go
+++ b/libgo/go/go/internal/gccgoimporter/importer_test.go
@@ -101,6 +101,7 @@
 	{pkgpath: "unicode", name: "IsUpper", want: "func IsUpper(r rune) bool"},
 	{pkgpath: "unicode", name: "MaxRune", want: "const MaxRune untyped rune", wantval: "1114111"},
 	{pkgpath: "imports", wantinits: []string{"imports..import", "fmt..import", "math..import"}},
+	{pkgpath: "alias", name: "IntAlias2", want: "type IntAlias2 = Int"},
 }
 
 func TestGoxImporter(t *testing.T) {
diff --git a/libgo/go/go/internal/gccgoimporter/parser.go b/libgo/go/go/internal/gccgoimporter/parser.go
index 3b97c96..8a1ad5f 100644
--- a/libgo/go/go/internal/gccgoimporter/parser.go
+++ b/libgo/go/go/internal/gccgoimporter/parser.go
@@ -370,27 +370,41 @@
 	return types.NewConst(token.NoPos, pkg, name, typ, val)
 }
 
-// TypeName = ExportedName .
-func (p *parser) parseTypeName() *types.TypeName {
-	pkg, name := p.parseExportedName()
-	scope := pkg.Scope()
-	if obj := scope.Lookup(name); obj != nil {
-		return obj.(*types.TypeName)
-	}
-	obj := types.NewTypeName(token.NoPos, pkg, name, nil)
-	// a named type may be referred to before the underlying type
-	// is known - set it up
-	types.NewNamed(obj, nil, nil)
-	scope.Insert(obj)
-	return obj
-}
-
-// NamedType = TypeName Type { Method } .
+// NamedType = TypeName [ "=" ] Type { Method } .
+// TypeName  = ExportedName .
 // Method    = "func" "(" Param ")" Name ParamList ResultList ";" .
 func (p *parser) parseNamedType(n int) types.Type {
-	obj := p.parseTypeName()
+	pkg, name := p.parseExportedName()
+	scope := pkg.Scope()
 
-	pkg := obj.Pkg()
+	if p.tok == '=' {
+		// type alias
+		p.next()
+		typ := p.parseType(pkg)
+		if obj := scope.Lookup(name); obj != nil {
+			typ = obj.Type() // use previously imported type
+			if typ == nil {
+				p.errorf("%v (type alias) used in cycle", obj)
+			}
+		} else {
+			obj = types.NewTypeName(token.NoPos, pkg, name, typ)
+			scope.Insert(obj)
+		}
+		p.typeMap[n] = typ
+		return typ
+	}
+
+	// named type
+	obj := scope.Lookup(name)
+	if obj == nil {
+		// a named type may be referred to before the underlying type
+		// is known - set it up
+		tname := types.NewTypeName(token.NoPos, pkg, name, nil)
+		types.NewNamed(tname, nil, nil)
+		scope.Insert(tname)
+		obj = tname
+	}
+
 	typ := obj.Type()
 	p.typeMap[n] = typ
 
@@ -409,8 +423,8 @@
 		nt.SetUnderlying(underlying.Underlying())
 	}
 
+	// collect associated methods
 	for p.tok == scanner.Ident {
-		// collect associated methods
 		p.expectKeyword("func")
 		p.expect('(')
 		receiver, _ := p.parseParam(pkg)
@@ -725,7 +739,7 @@
 		case ';':
 			return
 		case '<':
-			p.parseType(p.pkg)
+			p.parseType(pkg)
 		case scanner.EOF:
 			p.error("unexpected EOF")
 		default:
diff --git a/libgo/go/go/internal/gcimporter/bimport.go b/libgo/go/go/internal/gcimporter/bimport.go
index a8f3490..2045f55 100644
--- a/libgo/go/go/internal/gcimporter/bimport.go
+++ b/libgo/go/go/internal/gcimporter/bimport.go
@@ -19,16 +19,18 @@
 )
 
 type importer struct {
-	imports map[string]*types.Package
-	data    []byte
-	path    string
-	buf     []byte // for reading strings
-	version int    // export format version
+	imports    map[string]*types.Package
+	data       []byte
+	importpath string
+	buf        []byte // for reading strings
+	version    int    // export format version
 
 	// object lists
-	strList       []string         // in order of appearance
-	pkgList       []*types.Package // in order of appearance
-	typList       []types.Type     // in order of appearance
+	strList       []string           // in order of appearance
+	pathList      []string           // in order of appearance
+	pkgList       []*types.Package   // in order of appearance
+	typList       []types.Type       // in order of appearance
+	interfaceList []*types.Interface // for delayed completion only
 	trackAllTypes bool
 
 	// position encoding
@@ -47,24 +49,26 @@
 // and returns the number of bytes consumed and a reference to the package.
 // If the export data version is not recognized or the format is otherwise
 // compromised, an error is returned.
-func BImportData(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string) (_ int, _ *types.Package, err error) {
+func BImportData(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string) (_ int, pkg *types.Package, err error) {
 	// catch panics and return them as errors
 	defer func() {
 		if e := recover(); e != nil {
 			// The package (filename) causing the problem is added to this
 			// error by a wrapper in the caller (Import in gcimporter.go).
+			// Return a (possibly nil or incomplete) package unchanged (see #16088).
 			err = fmt.Errorf("cannot import, possibly version skew (%v) - reinstall package", e)
 		}
 	}()
 
 	p := importer{
-		imports: imports,
-		data:    data,
-		path:    path,
-		version: -1,           // unknown version
-		strList: []string{""}, // empty string is mapped to 0
-		fset:    fset,
-		files:   make(map[string]*token.File),
+		imports:    imports,
+		data:       data,
+		importpath: path,
+		version:    -1,           // unknown version
+		strList:    []string{""}, // empty string is mapped to 0
+		pathList:   []string{""}, // empty string is mapped to 0
+		fset:       fset,
+		files:      make(map[string]*token.File),
 	}
 
 	// read version info
@@ -98,10 +102,10 @@
 
 	// read version specific flags - extend as necessary
 	switch p.version {
-	// case 4:
+	// case 6:
 	// 	...
 	//	fallthrough
-	case 3, 2, 1:
+	case 5, 4, 3, 2, 1:
 		p.debugFormat = p.rawStringln(p.rawByte()) == "debug"
 		p.trackAllTypes = p.int() != 0
 		p.posInfoFormat = p.int() != 0
@@ -117,7 +121,7 @@
 	p.typList = append(p.typList, predeclared...)
 
 	// read package data
-	pkg := p.pkg()
+	pkg = p.pkg()
 
 	// read objects of phase 1 only (see cmd/compiler/internal/gc/bexport.go)
 	objcount := 0
@@ -138,15 +142,9 @@
 	// ignore compiler-specific import data
 
 	// complete interfaces
-	for _, typ := range p.typList {
-		// If we only record named types (!p.trackAllTypes),
-		// we must check the underlying types here. If we
-		// track all types, the Underlying() method call is
-		// not needed.
-		// TODO(gri) Remove if p.trackAllTypes is gone.
-		if it, ok := typ.Underlying().(*types.Interface); ok {
-			it.Complete()
-		}
+	// TODO(gri) re-investigate if we still need to do this in a delayed fashion
+	for _, typ := range p.interfaceList {
+		typ.Complete()
 	}
 
 	// record all referenced packages as imports
@@ -173,12 +171,17 @@
 
 	// otherwise, i is the package tag (< 0)
 	if i != packageTag {
-		errorf("unexpected package tag %d", i)
+		errorf("unexpected package tag %d version %d", i, p.version)
 	}
 
 	// read package data
 	name := p.string()
-	path := p.string()
+	var path string
+	if p.version >= 5 {
+		path = p.path()
+	} else {
+		path = p.string()
+	}
 
 	// we should never see an empty package name
 	if name == "" {
@@ -193,7 +196,7 @@
 
 	// if the package was imported before, use that one; otherwise create a new one
 	if path == "" {
-		path = p.path
+		path = p.importpath
 	}
 	pkg := p.imports[path]
 	if pkg == nil {
@@ -208,7 +211,6 @@
 }
 
 // objTag returns the tag value for each object kind.
-// obj must not be a *types.Alias.
 func objTag(obj types.Object) int {
 	switch obj.(type) {
 	case *types.Const:
@@ -219,7 +221,6 @@
 		return varTag
 	case *types.Func:
 		return funcTag
-	// Aliases are not exported multiple times, thus we should not see them here.
 	default:
 		errorf("unexpected object: %v (%T)", obj, obj) // panics
 		panic("unreachable")
@@ -237,14 +238,14 @@
 	pkg := obj.Pkg()
 	if alt := pkg.Scope().Insert(obj); alt != nil {
 		// This can only trigger if we import a (non-type) object a second time.
-		// Excluding aliases, this cannot happen because 1) we only import a package
+		// Excluding type aliases, this cannot happen because 1) we only import a package
 		// once; and b) we ignore compiler-specific export data which may contain
 		// functions whose inlined function bodies refer to other functions that
 		// were already imported.
-		// However, aliases require reexporting the original object, so we need
+		// However, type aliases require reexporting the original type, so we need
 		// to allow it (see also the comment in cmd/compile/internal/gc/bimport.go,
 		// method importer.obj, switch case importing functions).
-		// Note that the original itself cannot be an alias.
+		// TODO(gri) review/update this comment once the gc compiler handles type aliases.
 		if !sameObj(obj, alt) {
 			errorf("inconsistent import:\n\t%v\npreviously imported as:\n\t%v\n", obj, alt)
 		}
@@ -260,6 +261,13 @@
 		val := p.value()
 		p.declare(types.NewConst(pos, pkg, name, typ, val))
 
+	case aliasTag:
+		// TODO(gri) verify type alias hookup is correct
+		pos := p.pos()
+		pkg, name := p.qualifiedName()
+		typ := p.typ(nil)
+		p.declare(types.NewTypeName(pos, pkg, name, typ))
+
 	case typeTag:
 		p.typ(nil)
 
@@ -277,24 +285,13 @@
 		sig := types.NewSignature(nil, params, result, isddd)
 		p.declare(types.NewFunc(pos, pkg, name, sig))
 
-	case aliasTag:
-		pos := p.pos()
-		name := p.string()
-		var orig types.Object
-		if pkg, name := p.qualifiedName(); pkg != nil {
-			orig = pkg.Scope().Lookup(name)
-		}
-		// Alias-related code. Keep for now.
-		_ = pos
-		_ = name
-		_ = orig
-		// p.declare(types.NewAlias(pos, p.pkgList[0], name, orig))
-
 	default:
 		errorf("unexpected object tag %d", tag)
 	}
 }
 
+const deltaNewFile = -64 // see cmd/compile/internal/gc/bexport.go
+
 func (p *importer) pos() token.Pos {
 	if !p.posInfoFormat {
 		return token.NoPos
@@ -302,15 +299,26 @@
 
 	file := p.prevFile
 	line := p.prevLine
-	if delta := p.int(); delta != 0 {
-		// line changed
-		line += delta
-	} else if n := p.int(); n >= 0 {
-		// file changed
-		file = p.prevFile[:n] + p.string()
-		p.prevFile = file
-		line = p.int()
+	delta := p.int()
+	line += delta
+	if p.version >= 5 {
+		if delta == deltaNewFile {
+			if n := p.int(); n >= 0 {
+				// file changed
+				file = p.path()
+				line = n
+			}
+		}
+	} else {
+		if delta == 0 {
+			if n := p.int(); n >= 0 {
+				// file changed
+				file = p.prevFile[:n] + p.string()
+				line = p.int()
+			}
+		}
 	}
+	p.prevFile = file
 	p.prevLine = line
 
 	// Synthesize a token.Pos
@@ -349,9 +357,7 @@
 
 func (p *importer) qualifiedName() (pkg *types.Package, name string) {
 	name = p.string()
-	if name != "" {
-		pkg = p.pkg()
-	}
+	pkg = p.pkg()
 	return
 }
 
@@ -501,12 +507,14 @@
 			p.record(nil)
 		}
 
-		// no embedded interfaces with gc compiler
-		if p.int() != 0 {
-			errorf("unexpected embedded interface")
+		var embeddeds []*types.Named
+		for n := p.int(); n > 0; n-- {
+			p.pos()
+			embeddeds = append(embeddeds, p.typ(parent).(*types.Named))
 		}
 
-		t := types.NewInterface(p.methodList(parent), nil)
+		t := types.NewInterface(p.methodList(parent), embeddeds)
+		p.interfaceList = append(p.interfaceList, t)
 		if p.trackAllTypes {
 			p.typList[n] = t
 		}
@@ -556,17 +564,17 @@
 		fields = make([]*types.Var, n)
 		tags = make([]string, n)
 		for i := range fields {
-			fields[i] = p.field(parent)
-			tags[i] = p.string()
+			fields[i], tags[i] = p.field(parent)
 		}
 	}
 	return
 }
 
-func (p *importer) field(parent *types.Package) *types.Var {
+func (p *importer) field(parent *types.Package) (*types.Var, string) {
 	pos := p.pos()
-	pkg, name := p.fieldName(parent)
+	pkg, name, alias := p.fieldName(parent)
 	typ := p.typ(parent)
+	tag := p.string()
 
 	anonymous := false
 	if name == "" {
@@ -578,12 +586,15 @@
 		case *types.Named:
 			name = typ.Obj().Name()
 		default:
-			errorf("anonymous field expected")
+			errorf("named base type expected")
 		}
 		anonymous = true
+	} else if alias {
+		// anonymous field: we have an explicit name because it's an alias
+		anonymous = true
 	}
 
-	return types.NewField(pos, pkg, name, typ, anonymous)
+	return types.NewField(pos, pkg, name, typ, anonymous), tag
 }
 
 func (p *importer) methodList(parent *types.Package) (methods []*types.Func) {
@@ -598,31 +609,42 @@
 
 func (p *importer) method(parent *types.Package) *types.Func {
 	pos := p.pos()
-	pkg, name := p.fieldName(parent)
+	pkg, name, _ := p.fieldName(parent)
 	params, isddd := p.paramList()
 	result, _ := p.paramList()
 	sig := types.NewSignature(nil, params, result, isddd)
 	return types.NewFunc(pos, pkg, name, sig)
 }
 
-func (p *importer) fieldName(parent *types.Package) (*types.Package, string) {
-	name := p.string()
-	pkg := parent
+func (p *importer) fieldName(parent *types.Package) (pkg *types.Package, name string, alias bool) {
+	name = p.string()
+	pkg = parent
 	if pkg == nil {
 		// use the imported package instead
 		pkg = p.pkgList[0]
 	}
 	if p.version == 0 && name == "_" {
 		// version 0 didn't export a package for _ fields
-		return pkg, name
+		return
 	}
-	if name != "" && !exported(name) {
-		if name == "?" {
-			name = ""
-		}
+	switch name {
+	case "":
+		// 1) field name matches base type name and is exported: nothing to do
+	case "?":
+		// 2) field name matches base type name and is not exported: need package
+		name = ""
 		pkg = p.pkg()
+	case "@":
+		// 3) field name doesn't match type name (alias)
+		name = p.string()
+		alias = true
+		fallthrough
+	default:
+		if !exported(name) {
+			pkg = p.pkg()
+		}
 	}
-	return pkg, name
+	return
 }
 
 func (p *importer) paramList() (*types.Tuple, bool) {
@@ -774,6 +796,26 @@
 	return p.rawInt64()
 }
 
+func (p *importer) path() string {
+	if p.debugFormat {
+		p.marker('p')
+	}
+	// if the path was seen before, i is its index (>= 0)
+	// (the empty string is at index 0)
+	i := p.rawInt64()
+	if i >= 0 {
+		return p.pathList[i]
+	}
+	// otherwise, i is the negative path length (< 0)
+	a := make([]string, -i)
+	for n := range a {
+		a[n] = p.string()
+	}
+	s := strings.Join(a, "/")
+	p.pathList = append(p.pathList, s)
+	return s
+}
+
 func (p *importer) string() string {
 	if p.debugFormat {
 		p.marker('s')
@@ -893,7 +935,7 @@
 	nilTag     // only used by gc (appears in exported inlined function bodies)
 	unknownTag // not used by gc (only appears in packages with errors)
 
-	// Aliases
+	// Type aliases
 	aliasTag
 )
 
@@ -917,7 +959,7 @@
 	types.Typ[types.Complex128],
 	types.Typ[types.String],
 
-	// aliases
+	// basic type aliases
 	types.Universe.Lookup("byte").Type(),
 	types.Universe.Lookup("rune").Type(),
 
diff --git a/libgo/go/go/internal/gcimporter/gcimporter.go b/libgo/go/go/internal/gcimporter/gcimporter.go
index f99f0f8..f3f90f2 100644
--- a/libgo/go/go/internal/gcimporter/gcimporter.go
+++ b/libgo/go/go/internal/gcimporter/gcimporter.go
@@ -43,6 +43,7 @@
 		}
 		bp, _ := build.Import(path, srcDir, build.FindOnly|build.AllowBinary)
 		if bp.PkgObj == "" {
+			id = path // make sure we have an id to print in error message
 			return
 		}
 		noext = strings.TrimSuffix(bp.PkgObj, ".a")
@@ -89,7 +90,7 @@
 		if path == "unsafe" {
 			return types.Unsafe, nil
 		}
-		err = fmt.Errorf("can't find import: %s", id)
+		err = fmt.Errorf("can't find import: %q", id)
 		return
 	}
 
diff --git a/libgo/go/go/internal/gcimporter/gcimporter_test.go b/libgo/go/go/internal/gcimporter/gcimporter_test.go
index a0697fa..c34f07c 100644
--- a/libgo/go/go/internal/gcimporter/gcimporter_test.go
+++ b/libgo/go/go/internal/gcimporter/gcimporter_test.go
@@ -92,7 +92,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	if outFn := compile(t, "testdata", "exports.go"); outFn != "" {
@@ -124,7 +123,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	const dir = "./testdata/versions"
@@ -188,7 +186,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	dt := maxTime
@@ -205,7 +202,7 @@
 }{
 	{"math.Pi", "const Pi untyped float"},
 	{"io.Reader", "type Reader interface{Read(p []byte) (n int, err error)}"},
-	{"io.ReadWriter", "type ReadWriter interface{Read(p []byte) (n int, err error); Write(p []byte) (n int, err error)}"},
+	{"io.ReadWriter", "type ReadWriter interface{Reader; Writer}"},
 	{"math.Sin", "func Sin(x float64) float64"},
 	// TODO(gri) add more tests
 }
@@ -216,7 +213,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	for _, test := range importedObjectTests {
@@ -252,13 +248,9 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
-	pkg, err := Import(make(map[string]*types.Package), "strings", ".")
-	if err != nil {
-		t.Fatal(err)
-	}
+	pkg := importPkg(t, "strings")
 
 	scope := pkg.Scope()
 	for _, name := range scope.Names() {
@@ -285,7 +277,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	imports := make(map[string]*types.Package)
@@ -309,7 +300,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	// On windows, we have to set the -D option for the compiler to avoid having a drive
@@ -326,10 +316,7 @@
 	}
 
 	// import must succeed (test for issue at hand)
-	pkg, err := Import(make(map[string]*types.Package), "./testdata/b", ".")
-	if err != nil {
-		t.Fatal(err)
-	}
+	pkg := importPkg(t, "./testdata/b")
 
 	// make sure all indirectly imported packages have names
 	for _, imp := range pkg.Imports() {
@@ -345,7 +332,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	// import go/internal/gcimporter which imports go/types partially
@@ -368,10 +354,7 @@
 	}
 
 	// look for go/types.Object type
-	obj := goTypesPkg.Scope().Lookup("Object")
-	if obj == nil {
-		t.Fatal("go/types.Object not found")
-	}
+	obj := lookupObj(t, goTypesPkg.Scope(), "Object")
 	typ, ok := obj.Type().(*types.Named)
 	if !ok {
 		t.Fatalf("go/types.Object type is %v; wanted named type", typ)
@@ -395,7 +378,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	// On windows, we have to set the -D option for the compiler to avoid having a drive
@@ -434,7 +416,6 @@
 	// This package only handles gc export data.
 	if runtime.Compiler != "gc" {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
-		return
 	}
 
 	// On windows, we have to set the -D option for the compiler to avoid having a drive
@@ -447,8 +428,47 @@
 		defer os.Remove(f)
 	}
 
-	imports := make(map[string]*types.Package)
-	if _, err := Import(imports, "./testdata/issue15920", "."); err != nil {
+	importPkg(t, "./testdata/issue15920")
+}
+
+func TestIssue20046(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	// This package only handles gc export data.
+	if runtime.Compiler != "gc" {
+		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
+	}
+
+	// On windows, we have to set the -D option for the compiler to avoid having a drive
+	// letter and an illegal ':' in the import path - just skip it (see also issue #3483).
+	if runtime.GOOS == "windows" {
+		t.Skip("avoid dealing with relative paths/drive letters on windows")
+	}
+
+	if f := compile(t, "testdata", "issue20046.go"); f != "" {
+		defer os.Remove(f)
+	}
+
+	// "./issue20046".V.M must exist
+	pkg := importPkg(t, "./testdata/issue20046")
+	obj := lookupObj(t, pkg.Scope(), "V")
+	if m, index, indirect := types.LookupFieldOrMethod(obj.Type(), false, nil, "M"); m == nil {
+		t.Fatalf("V.M not found (index = %v, indirect = %v)", index, indirect)
+	}
+}
+
+func importPkg(t *testing.T, path string) *types.Package {
+	pkg, err := Import(make(map[string]*types.Package), path, ".")
+	if err != nil {
 		t.Fatal(err)
 	}
+	return pkg
+}
+
+func lookupObj(t *testing.T, scope *types.Scope, name string) types.Object {
+	if obj := scope.Lookup(name); obj != nil {
+		return obj
+	}
+	t.Fatalf("%s not found", name)
+	return nil
 }
diff --git a/libgo/go/go/internal/gcimporter/testdata/issue20046.go b/libgo/go/go/internal/gcimporter/testdata/issue20046.go
new file mode 100644
index 0000000..c63ee82
--- /dev/null
+++ b/libgo/go/go/internal/gcimporter/testdata/issue20046.go
@@ -0,0 +1,9 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+var V interface {
+	M()
+}
diff --git a/libgo/go/go/internal/srcimporter/srcimporter.go b/libgo/go/go/internal/srcimporter/srcimporter.go
new file mode 100644
index 0000000..50cf361
--- /dev/null
+++ b/libgo/go/go/internal/srcimporter/srcimporter.go
@@ -0,0 +1,211 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package srcimporter implements importing directly
+// from source files rather than installed packages.
+package srcimporter // import "go/internal/srcimporter"
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"path/filepath"
+	"sync"
+)
+
+// An Importer provides the context for importing packages from source code.
+type Importer struct {
+	ctxt     *build.Context
+	fset     *token.FileSet
+	sizes    types.Sizes
+	packages map[string]*types.Package
+}
+
+// NewImporter returns a new Importer for the given context, file set, and map
+// of packages. The context is used to resolve import paths to package paths,
+// and identifying the files belonging to the package. If the context provides
+// non-nil file system functions, they are used instead of the regular package
+// os functions. The file set is used to track position information of package
+// files; and imported packages are added to the packages map.
+func New(ctxt *build.Context, fset *token.FileSet, packages map[string]*types.Package) *Importer {
+	return &Importer{
+		ctxt:     ctxt,
+		fset:     fset,
+		sizes:    types.SizesFor(ctxt.Compiler, ctxt.GOARCH), // uses go/types default if GOARCH not found
+		packages: packages,
+	}
+}
+
+// Importing is a sentinel taking the place in Importer.packages
+// for a package that is in the process of being imported.
+var importing types.Package
+
+// Import(path) is a shortcut for ImportFrom(path, "", 0).
+func (p *Importer) Import(path string) (*types.Package, error) {
+	return p.ImportFrom(path, "", 0)
+}
+
+// ImportFrom imports the package with the given import path resolved from the given srcDir,
+// adds the new package to the set of packages maintained by the importer, and returns the
+// package. Package path resolution and file system operations are controlled by the context
+// maintained with the importer. The import mode must be zero but is otherwise ignored.
+// Packages that are not comprised entirely of pure Go files may fail to import because the
+// type checker may not be able to determine all exported entities (e.g. due to cgo dependencies).
+func (p *Importer) ImportFrom(path, srcDir string, mode types.ImportMode) (*types.Package, error) {
+	if mode != 0 {
+		panic("non-zero import mode")
+	}
+
+	// determine package path (do vendor resolution)
+	var bp *build.Package
+	var err error
+	switch {
+	default:
+		if abs, err := p.absPath(srcDir); err == nil { // see issue #14282
+			srcDir = abs
+		}
+		bp, err = p.ctxt.Import(path, srcDir, build.FindOnly)
+
+	case build.IsLocalImport(path):
+		// "./x" -> "srcDir/x"
+		bp, err = p.ctxt.ImportDir(filepath.Join(srcDir, path), build.FindOnly)
+
+	case p.isAbsPath(path):
+		return nil, fmt.Errorf("invalid absolute import path %q", path)
+	}
+	if err != nil {
+		return nil, err // err may be *build.NoGoError - return as is
+	}
+
+	// package unsafe is known to the type checker
+	if bp.ImportPath == "unsafe" {
+		return types.Unsafe, nil
+	}
+
+	// no need to re-import if the package was imported completely before
+	pkg := p.packages[bp.ImportPath]
+	if pkg != nil {
+		if pkg == &importing {
+			return nil, fmt.Errorf("import cycle through package %q", bp.ImportPath)
+		}
+		if !pkg.Complete() {
+			// Package exists but is not complete - we cannot handle this
+			// at the moment since the source importer replaces the package
+			// wholesale rather than augmenting it (see #19337 for details).
+			// Return incomplete package with error (see #16088).
+			return pkg, fmt.Errorf("reimported partially imported package %q", bp.ImportPath)
+		}
+		return pkg, nil
+	}
+
+	p.packages[bp.ImportPath] = &importing
+	defer func() {
+		// clean up in case of error
+		// TODO(gri) Eventually we may want to leave a (possibly empty)
+		// package in the map in all cases (and use that package to
+		// identify cycles). See also issue 16088.
+		if p.packages[bp.ImportPath] == &importing {
+			p.packages[bp.ImportPath] = nil
+		}
+	}()
+
+	// collect package files
+	bp, err = p.ctxt.ImportDir(bp.Dir, 0)
+	if err != nil {
+		return nil, err // err may be *build.NoGoError - return as is
+	}
+	var filenames []string
+	filenames = append(filenames, bp.GoFiles...)
+	filenames = append(filenames, bp.CgoFiles...)
+
+	files, err := p.parseFiles(bp.Dir, filenames)
+	if err != nil {
+		return nil, err
+	}
+
+	// type-check package files
+	conf := types.Config{
+		IgnoreFuncBodies: true,
+		FakeImportC:      true,
+		Importer:         p,
+		Sizes:            p.sizes,
+	}
+	pkg, err = conf.Check(bp.ImportPath, p.fset, files, nil)
+	if err != nil {
+		// Type-checking stops after the first error (types.Config.Error is not set),
+		// so the returned package is very likely incomplete. Don't return it since
+		// we don't know its condition: It's very likely unsafe to use and it's also
+		// not added to p.packages which may cause further problems (issue #20837).
+		return nil, fmt.Errorf("type-checking package %q failed (%v)", bp.ImportPath, err)
+	}
+
+	p.packages[bp.ImportPath] = pkg
+	return pkg, nil
+}
+
+func (p *Importer) parseFiles(dir string, filenames []string) ([]*ast.File, error) {
+	open := p.ctxt.OpenFile // possibly nil
+
+	files := make([]*ast.File, len(filenames))
+	errors := make([]error, len(filenames))
+
+	var wg sync.WaitGroup
+	wg.Add(len(filenames))
+	for i, filename := range filenames {
+		go func(i int, filepath string) {
+			defer wg.Done()
+			if open != nil {
+				src, err := open(filepath)
+				if err != nil {
+					errors[i] = fmt.Errorf("opening package file %s failed (%v)", filepath, err)
+					return
+				}
+				files[i], errors[i] = parser.ParseFile(p.fset, filepath, src, 0)
+				src.Close() // ignore Close error - parsing may have succeeded which is all we need
+			} else {
+				// Special-case when ctxt doesn't provide a custom OpenFile and use the
+				// parser's file reading mechanism directly. This appears to be quite a
+				// bit faster than opening the file and providing an io.ReaderCloser in
+				// both cases.
+				// TODO(gri) investigate performance difference (issue #19281)
+				files[i], errors[i] = parser.ParseFile(p.fset, filepath, nil, 0)
+			}
+		}(i, p.joinPath(dir, filename))
+	}
+	wg.Wait()
+
+	// if there are errors, return the first one for deterministic results
+	for _, err := range errors {
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return files, nil
+}
+
+// context-controlled file system operations
+
+func (p *Importer) absPath(path string) (string, error) {
+	// TODO(gri) This should be using p.ctxt.AbsPath which doesn't
+	// exist but probably should. See also issue #14282.
+	return filepath.Abs(path)
+}
+
+func (p *Importer) isAbsPath(path string) bool {
+	if f := p.ctxt.IsAbsPath; f != nil {
+		return f(path)
+	}
+	return filepath.IsAbs(path)
+}
+
+func (p *Importer) joinPath(elem ...string) string {
+	if f := p.ctxt.JoinPath; f != nil {
+		return f(elem...)
+	}
+	return filepath.Join(elem...)
+}
diff --git a/libgo/go/go/internal/srcimporter/srcimporter_test.go b/libgo/go/go/internal/srcimporter/srcimporter_test.go
new file mode 100644
index 0000000..79921b5
--- /dev/null
+++ b/libgo/go/go/internal/srcimporter/srcimporter_test.go
@@ -0,0 +1,150 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package srcimporter
+
+import (
+	"go/build"
+	"go/token"
+	"go/types"
+	"internal/testenv"
+	"io/ioutil"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+)
+
+const maxTime = 2 * time.Second
+
+var importer = New(&build.Default, token.NewFileSet(), make(map[string]*types.Package))
+
+func doImport(t *testing.T, path, srcDir string) {
+	t0 := time.Now()
+	if _, err := importer.ImportFrom(path, srcDir, 0); err != nil {
+		// don't report an error if there's no buildable Go files
+		if _, nogo := err.(*build.NoGoError); !nogo {
+			t.Errorf("import %q failed (%v)", path, err)
+		}
+		return
+	}
+	t.Logf("import %q: %v", path, time.Since(t0))
+}
+
+// walkDir imports the all the packages with the given path
+// prefix recursively. It returns the number of packages
+// imported and whether importing was aborted because time
+// has passed endTime.
+func walkDir(t *testing.T, path string, endTime time.Time) (int, bool) {
+	if time.Now().After(endTime) {
+		t.Log("testing time used up")
+		return 0, true
+	}
+
+	// ignore fake packages and testdata directories
+	if path == "builtin" || path == "unsafe" || strings.HasSuffix(path, "testdata") {
+		return 0, false
+	}
+
+	list, err := ioutil.ReadDir(filepath.Join(runtime.GOROOT(), "src", path))
+	if err != nil {
+		t.Fatalf("walkDir %s failed (%v)", path, err)
+	}
+
+	nimports := 0
+	hasGoFiles := false
+	for _, f := range list {
+		if f.IsDir() {
+			n, abort := walkDir(t, filepath.Join(path, f.Name()), endTime)
+			nimports += n
+			if abort {
+				return nimports, true
+			}
+		} else if strings.HasSuffix(f.Name(), ".go") {
+			hasGoFiles = true
+		}
+	}
+
+	if hasGoFiles {
+		doImport(t, path, "")
+		nimports++
+	}
+
+	return nimports, false
+}
+
+func TestImportStdLib(t *testing.T) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	dt := maxTime
+	if testing.Short() && testenv.Builder() == "" {
+		dt = 500 * time.Millisecond
+	}
+	nimports, _ := walkDir(t, "", time.Now().Add(dt)) // installed packages
+	t.Logf("tested %d imports", nimports)
+}
+
+var importedObjectTests = []struct {
+	name string
+	want string
+}{
+	{"flag.Bool", "func Bool(name string, value bool, usage string) *bool"},
+	{"io.Reader", "type Reader interface{Read(p []byte) (n int, err error)}"},
+	{"io.ReadWriter", "type ReadWriter interface{Reader; Writer}"}, // go/types.gcCompatibilityMode is off => interface not flattened
+	{"math.Pi", "const Pi untyped float"},
+	{"math.Sin", "func Sin(x float64) float64"},
+	{"math/big.Int", "type Int struct{neg bool; abs nat}"},
+	{"golang_org/x/text/unicode/norm.MaxSegmentSize", "const MaxSegmentSize untyped int"},
+}
+
+func TestImportedTypes(t *testing.T) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	for _, test := range importedObjectTests {
+		s := strings.Split(test.name, ".")
+		if len(s) != 2 {
+			t.Fatal("invalid test data format")
+		}
+		importPath := s[0]
+		objName := s[1]
+
+		pkg, err := importer.ImportFrom(importPath, ".", 0)
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+
+		obj := pkg.Scope().Lookup(objName)
+		if obj == nil {
+			t.Errorf("%s: object not found", test.name)
+			continue
+		}
+
+		got := types.ObjectString(obj, types.RelativeTo(pkg))
+		if got != test.want {
+			t.Errorf("%s: got %q; want %q", test.name, got, test.want)
+		}
+	}
+}
+
+func TestReimport(t *testing.T) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	// Reimporting a partially imported (incomplete) package is not supported (see issue #19337).
+	// Make sure we recognize the situation and report an error.
+
+	mathPkg := types.NewPackage("math", "math") // incomplete package
+	importer := New(&build.Default, token.NewFileSet(), map[string]*types.Package{mathPkg.Path(): mathPkg})
+	_, err := importer.ImportFrom("math", ".", 0)
+	if err == nil || !strings.HasPrefix(err.Error(), "reimport") {
+		t.Errorf("got %v; want reimport error", err)
+	}
+}
diff --git a/libgo/go/go/parser/error_test.go b/libgo/go/go/parser/error_test.go
index 1a08d5a..ef91e1e 100644
--- a/libgo/go/go/parser/error_test.go
+++ b/libgo/go/go/parser/error_test.go
@@ -66,7 +66,7 @@
 // expectedErrors collects the regular expressions of ERROR comments found
 // in files and returns them as a map of error positions to error messages.
 //
-func expectedErrors(t *testing.T, fset *token.FileSet, filename string, src []byte) map[token.Pos]string {
+func expectedErrors(fset *token.FileSet, filename string, src []byte) map[token.Pos]string {
 	errors := make(map[token.Pos]string)
 
 	var s scanner.Scanner
@@ -161,7 +161,7 @@
 
 	// we are expecting the following errors
 	// (collect these after parsing a file so that it is found in the file set)
-	expected := expectedErrors(t, fset, filename, src)
+	expected := expectedErrors(fset, filename, src)
 
 	// verify errors returned by the parser
 	compareErrors(t, fset, expected, found)
diff --git a/libgo/go/go/parser/parser.go b/libgo/go/go/parser/parser.go
index d3ef7db..2b58724 100644
--- a/libgo/go/go/parser/parser.go
+++ b/libgo/go/go/parser/parser.go
@@ -327,7 +327,7 @@
 			// The comment is on same line as the previous token; it
 			// cannot be a lead comment but may be a line comment.
 			comment, endline = p.consumeCommentGroup(0)
-			if p.file.Line(p.pos) != endline {
+			if p.file.Line(p.pos) != endline || p.tok == token.EOF {
 				// The next token is on a different line, thus
 				// the last comment group is a line comment.
 				p.lineComment = comment
@@ -1707,8 +1707,8 @@
 		}
 		// The label declaration typically starts at x[0].Pos(), but the label
 		// declaration may be erroneous due to a token after that position (and
-		// before the ':'). If SpuriousErrors is not set, the (only) error re-
-		// ported for the line is the illegal label error instead of the token
+		// before the ':'). If SpuriousErrors is not set, the (only) error
+		// reported for the line is the illegal label error instead of the token
 		// before the ':' that caused the problem. Thus, use the (latest) colon
 		// position for error reporting.
 		p.error(colon, "illegal label declaration")
@@ -2327,7 +2327,10 @@
 	// (Global identifiers are resolved in a separate phase after parsing.)
 	spec := &ast.TypeSpec{Doc: doc, Name: ident}
 	p.declare(spec, nil, p.topScope, ast.Typ, ident)
-
+	if p.tok == token.ASSIGN {
+		spec.Assign = p.pos
+		p.next()
+	}
 	spec.Type = p.parseType()
 	p.expectSemi() // call before accessing p.linecomment
 	spec.Comment = p.lineComment
diff --git a/libgo/go/go/parser/parser_test.go b/libgo/go/go/parser/parser_test.go
index c7bb36d..fb35a88 100644
--- a/libgo/go/go/parser/parser_test.go
+++ b/libgo/go/go/parser/parser_test.go
@@ -531,3 +531,18 @@
 		}
 	}
 }
+
+func TestLastLineComment(t *testing.T) {
+	const src = `package main
+type x int // comment
+`
+	fset := token.NewFileSet()
+	f, err := ParseFile(fset, "", src, ParseComments)
+	if err != nil {
+		t.Fatal(err)
+	}
+	comment := f.Decls[0].(*ast.GenDecl).Specs[0].(*ast.TypeSpec).Comment.List[0].Text
+	if comment != "// comment" {
+		t.Errorf("got %q, want %q", comment, "// comment")
+	}
+}
diff --git a/libgo/go/go/parser/performance_test.go b/libgo/go/go/parser/performance_test.go
index b2e1c11..f2732c0 100644
--- a/libgo/go/go/parser/performance_test.go
+++ b/libgo/go/go/parser/performance_test.go
@@ -10,12 +10,17 @@
 	"testing"
 )
 
-func BenchmarkParse(b *testing.B) {
-	src, err := ioutil.ReadFile("parser.go")
+var src = readFile("parser.go")
+
+func readFile(filename string) []byte {
+	data, err := ioutil.ReadFile(filename)
 	if err != nil {
-		b.Fatal(err)
+		panic(err)
 	}
-	b.ResetTimer()
+	return data
+}
+
+func BenchmarkParse(b *testing.B) {
 	b.SetBytes(int64(len(src)))
 	for i := 0; i < b.N; i++ {
 		if _, err := ParseFile(token.NewFileSet(), "", src, ParseComments); err != nil {
diff --git a/libgo/go/go/parser/short_test.go b/libgo/go/go/parser/short_test.go
index cdd343e..6f8ef6b 100644
--- a/libgo/go/go/parser/short_test.go
+++ b/libgo/go/go/parser/short_test.go
@@ -46,6 +46,8 @@
 	`package p; const (x = 0; y; z)`, // issue 9639
 	`package p; var _ = map[P]int{P{}:0, {}:1}`,
 	`package p; var _ = map[*P]int{&P{}:0, {}:1}`,
+	`package p; type T = int`,
+	`package p; type (T = p.T; _ = struct{}; x = *T)`,
 }
 
 func TestValid(t *testing.T) {
diff --git a/libgo/go/go/printer/nodes.go b/libgo/go/go/printer/nodes.go
index ea43286..4eaadeb 100644
--- a/libgo/go/go/printer/nodes.go
+++ b/libgo/go/go/printer/nodes.go
@@ -887,8 +887,6 @@
 	default:
 		panic("unreachable")
 	}
-
-	return
 }
 
 func (p *printer) possibleSelectorExpr(expr ast.Expr, prec1, depth int) bool {
@@ -1268,8 +1266,6 @@
 	default:
 		panic("unreachable")
 	}
-
-	return
 }
 
 // ----------------------------------------------------------------------------
@@ -1447,6 +1443,9 @@
 		} else {
 			p.print(vtab)
 		}
+		if s.Assign.IsValid() {
+			p.print(token.ASSIGN, blank)
+		}
 		p.expr(s.Type)
 		p.setComment(s.Comment)
 
@@ -1533,6 +1532,16 @@
 	return
 }
 
+// numLines returns the number of lines spanned by node n in the original source.
+func (p *printer) numLines(n ast.Node) int {
+	if from := n.Pos(); from.IsValid() {
+		if to := n.End(); to.IsValid() {
+			return p.lineFor(to) - p.lineFor(from) + 1
+		}
+	}
+	return infinity
+}
+
 // bodySize is like nodeSize but it is specialized for *ast.BlockStmt's.
 func (p *printer) bodySize(b *ast.BlockStmt, maxSize int) int {
 	pos1 := b.Pos()
@@ -1669,7 +1678,9 @@
 			if prev != tok || getDoc(d) != nil {
 				min = 2
 			}
-			p.linebreak(p.lineFor(d.Pos()), min, ignore, false)
+			// start a new section if the next declaration is a function
+			// that spans multiple lines (see also issue #19544)
+			p.linebreak(p.lineFor(d.Pos()), min, ignore, tok == token.FUNC && p.numLines(d) > 1)
 		}
 		p.decl(d)
 	}
diff --git a/libgo/go/go/printer/printer.go b/libgo/go/go/printer/printer.go
index be61dad..dbb4bbd 100644
--- a/libgo/go/go/printer/printer.go
+++ b/libgo/go/go/printer/printer.go
@@ -69,7 +69,7 @@
 	// The out position differs from the pos position when the result
 	// formatting differs from the source formatting (in the amount of
 	// white space). If there's a difference and SourcePos is set in
-	// ConfigMode, //line comments are used in the output to restore
+	// ConfigMode, //line directives are used in the output to restore
 	// original source positions for a reader.
 	pos     token.Position // current position in AST (source) space
 	out     token.Position // current position in output space
@@ -203,19 +203,20 @@
 	return p.cachedLine
 }
 
-// atLineBegin emits a //line comment if necessary and prints indentation.
-func (p *printer) atLineBegin(pos token.Position) {
-	// write a //line comment if necessary
-	if p.Config.Mode&SourcePos != 0 && pos.IsValid() && (p.out.Line != pos.Line || p.out.Filename != pos.Filename) {
+// writeLineDirective writes a //line directive if necessary.
+func (p *printer) writeLineDirective(pos token.Position) {
+	if pos.IsValid() && (p.out.Line != pos.Line || p.out.Filename != pos.Filename) {
 		p.output = append(p.output, tabwriter.Escape) // protect '\n' in //line from tabwriter interpretation
 		p.output = append(p.output, fmt.Sprintf("//line %s:%d\n", pos.Filename, pos.Line)...)
 		p.output = append(p.output, tabwriter.Escape)
-		// p.out must match the //line comment
+		// p.out must match the //line directive
 		p.out.Filename = pos.Filename
 		p.out.Line = pos.Line
 	}
+}
 
-	// write indentation
+// writeIndent writes indentation.
+func (p *printer) writeIndent() {
 	// use "hard" htabs - indentation columns
 	// must not be discarded by the tabwriter
 	n := p.Config.Indent + p.indent // include base indentation
@@ -230,9 +231,11 @@
 }
 
 // writeByte writes ch n times to p.output and updates p.pos.
+// Only used to write formatting (white space) characters.
 func (p *printer) writeByte(ch byte, n int) {
 	if p.out.Column == 1 {
-		p.atLineBegin(p.pos)
+		// no need to write line directives before white space
+		p.writeIndent()
 	}
 
 	for i := 0; i < n; i++ {
@@ -265,13 +268,16 @@
 //
 func (p *printer) writeString(pos token.Position, s string, isLit bool) {
 	if p.out.Column == 1 {
-		p.atLineBegin(pos)
+		if p.Config.Mode&SourcePos != 0 {
+			p.writeLineDirective(pos)
+		}
+		p.writeIndent()
 	}
 
 	if pos.IsValid() {
 		// update p.pos (if pos is invalid, continue with existing p.pos)
 		// Note: Must do this after handling line beginnings because
-		// atLineBegin updates p.pos if there's indentation, but p.pos
+		// writeIndent updates p.pos if there's indentation, but p.pos
 		// is the position of s.
 		p.pos = pos
 	}
@@ -325,7 +331,7 @@
 // after all pending comments, prev is the previous comment in
 // a group of comments (or nil), and tok is the next token.
 //
-func (p *printer) writeCommentPrefix(pos, next token.Position, prev, comment *ast.Comment, tok token.Token) {
+func (p *printer) writeCommentPrefix(pos, next token.Position, prev *ast.Comment, tok token.Token) {
 	if len(p.output) == 0 {
 		// the comment is the first item to be printed - don't write any whitespace
 		return
@@ -733,7 +739,7 @@
 	var last *ast.Comment
 	for p.commentBefore(next) {
 		for _, c := range p.comment.List {
-			p.writeCommentPrefix(p.posFor(c.Pos()), next, last, c, tok)
+			p.writeCommentPrefix(p.posFor(c.Pos()), next, last, tok)
 			p.writeComment(c)
 			last = c
 		}
@@ -1037,6 +1043,28 @@
 	return nil
 }
 
+func getLastComment(n ast.Node) *ast.CommentGroup {
+	switch n := n.(type) {
+	case *ast.Field:
+		return n.Comment
+	case *ast.ImportSpec:
+		return n.Comment
+	case *ast.ValueSpec:
+		return n.Comment
+	case *ast.TypeSpec:
+		return n.Comment
+	case *ast.GenDecl:
+		if len(n.Specs) > 0 {
+			return getLastComment(n.Specs[len(n.Specs)-1])
+		}
+	case *ast.File:
+		if len(n.Comments) > 0 {
+			return n.Comments[len(n.Comments)-1]
+		}
+	}
+	return nil
+}
+
 func (p *printer) printNode(node interface{}) error {
 	// unpack *CommentedNode, if any
 	var comments []*ast.CommentGroup
@@ -1060,6 +1088,11 @@
 		if doc := getDoc(n); doc != nil {
 			beg = doc.Pos()
 		}
+		if com := getLastComment(n); com != nil {
+			if e := com.End(); e > end {
+				end = e
+			}
+		}
 		// token.Pos values are global offsets, we can
 		// compare them directly
 		i := 0
@@ -1237,7 +1270,7 @@
 	RawFormat Mode = 1 << iota // do not use a tabwriter; if set, UseSpaces is ignored
 	TabIndent                  // use tabs for indentation independent of UseSpaces
 	UseSpaces                  // use spaces instead of tabs for alignment
-	SourcePos                  // emit //line comments to preserve original source positions
+	SourcePos                  // emit //line directives to preserve original source positions
 )
 
 // A Config node controls the output of Fprint.
@@ -1315,7 +1348,7 @@
 
 // Fprint "pretty-prints" an AST node to output.
 // It calls Config.Fprint with default settings.
-// Note that gofmt uses tabs for indentation but spaces for alignent;
+// Note that gofmt uses tabs for indentation but spaces for alignment;
 // use format.Node (package go/format) for output that matches gofmt.
 //
 func Fprint(output io.Writer, fset *token.FileSet, node interface{}) error {
diff --git a/libgo/go/go/printer/printer_test.go b/libgo/go/go/printer/printer_test.go
index 0badbfb..5984d2c 100644
--- a/libgo/go/go/printer/printer_test.go
+++ b/libgo/go/go/printer/printer_test.go
@@ -363,7 +363,7 @@
 	return n
 }
 
-// Verify that the SourcePos mode emits correct //line comments
+// Verify that the SourcePos mode emits correct //line directives
 // by testing that position information for matching identifiers
 // is maintained.
 func TestSourcePos(t *testing.T) {
@@ -394,7 +394,7 @@
 	}
 
 	// parse pretty printed original
-	// (//line comments must be interpreted even w/o parser.ParseComments set)
+	// (//line directives must be interpreted even w/o parser.ParseComments set)
 	f2, err := parser.ParseFile(fset, "", buf.Bytes(), 0)
 	if err != nil {
 		t.Fatalf("%s\n%s", err, buf.Bytes())
@@ -434,6 +434,53 @@
 	}
 }
 
+// Verify that the SourcePos mode doesn't emit unnecessary //line directives
+// before empty lines.
+func TestIssue5945(t *testing.T) {
+	const orig = `
+package p   // line 2
+func f() {} // line 3
+
+var x, y, z int
+
+
+func g() { // line 8
+}
+`
+
+	const want = `//line src.go:2
+package p
+
+//line src.go:3
+func f() {}
+
+var x, y, z int
+
+//line src.go:8
+func g() {
+}
+`
+
+	// parse original
+	f1, err := parser.ParseFile(fset, "src.go", orig, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// pretty-print original
+	var buf bytes.Buffer
+	err = (&Config{Mode: UseSpaces | SourcePos, Tabwidth: 8}).Fprint(&buf, fset, f1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := buf.String()
+
+	// compare original with desired output
+	if got != want {
+		t.Errorf("got:\n%s\nwant:\n%s\n", got, want)
+	}
+}
+
 var decls = []string{
 	`import "fmt"`,
 	"const pi = 3.1415\nconst e = 2.71828\n\nvar x = pi",
@@ -612,3 +659,54 @@
 		t.Error(err)
 	}
 }
+
+func TestCommentedNode(t *testing.T) {
+	const (
+		input = `package main
+
+func foo() {
+	// comment inside func
+}
+
+// leading comment
+type bar int // comment2
+
+`
+
+		foo = `func foo() {
+	// comment inside func
+}`
+
+		bar = `// leading comment
+type bar int	// comment2
+`
+	)
+
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "input.go", input, parser.ParseComments)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+
+	err = Fprint(&buf, fset, &CommentedNode{Node: f.Decls[0], Comments: f.Comments})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if buf.String() != foo {
+		t.Errorf("got %q, want %q", buf.String(), foo)
+	}
+
+	buf.Reset()
+
+	err = Fprint(&buf, fset, &CommentedNode{Node: f.Decls[1], Comments: f.Comments})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if buf.String() != bar {
+		t.Errorf("got %q, want %q", buf.String(), bar)
+	}
+}
diff --git a/libgo/go/go/printer/testdata/declarations.golden b/libgo/go/go/printer/testdata/declarations.golden
index 82f5e0f..bebc0ea 100644
--- a/libgo/go/go/printer/testdata/declarations.golden
+++ b/libgo/go/go/printer/testdata/declarations.golden
@@ -778,6 +778,12 @@
 	/* multi-line func because block is on multiple lines */
 }
 
+// test case for issue #19544
+func _()	{}
+func _longer_name_() {	// this comment must not force the {} from above to alignment
+	// multiple lines
+}
+
 // ellipsis parameters
 func _(...int)
 func _(...*int)
@@ -985,3 +991,18 @@
 	x	int
 	y	int
 })	// no extra comma between } and )
+
+// alias declarations
+
+type c0 struct{}
+type c1 = C
+type c2 = struct{ x int }
+type c3 = p.C
+type (
+	s	struct{}
+	a	= A
+	b	= A
+	c	= foo
+	d	= interface{}
+	ddd	= p.Foo
+)
diff --git a/libgo/go/go/printer/testdata/declarations.input b/libgo/go/go/printer/testdata/declarations.input
index a0a3783..a858051 100644
--- a/libgo/go/go/printer/testdata/declarations.input
+++ b/libgo/go/go/printer/testdata/declarations.input
@@ -795,6 +795,11 @@
 func _() {
 /* multi-line func because block is on multiple lines */ }
 
+// test case for issue #19544
+func _() {}
+func _longer_name_() { // this comment must not force the {} from above to alignment
+	// multiple lines
+}
 
 // ellipsis parameters
 func _(...int)
@@ -999,3 +1004,18 @@
 	x int
 	y int
 }) // no extra comma between } and )
+
+// alias declarations
+
+type c0 struct{}
+type c1 = C
+type c2 = struct{ x int}
+type c3 = p.C
+type (
+	s struct{}
+	a = A
+	b = A
+	c = foo
+	d = interface{}
+	ddd = p.Foo
+)
\ No newline at end of file
diff --git a/libgo/go/go/token/position.go b/libgo/go/go/token/position.go
index d4171d8..88d7416 100644
--- a/libgo/go/go/token/position.go
+++ b/libgo/go/go/token/position.go
@@ -71,7 +71,7 @@
 type Pos int
 
 // The zero value for Pos is NoPos; there is no file and line information
-// associated with it, and NoPos().IsValid() is false. NoPos is always
+// associated with it, and NoPos.IsValid() is false. NoPos is always
 // smaller than any other Pos value. The corresponding Position value
 // for NoPos is the zero value for Position.
 //
@@ -94,7 +94,8 @@
 	base int    // Pos value range for this file is [base...base+size]
 	size int    // file size as provided to AddFile
 
-	// lines and infos are protected by set.mutex
+	// lines and infos are protected by mutex
+	mutex sync.Mutex
 	lines []int // lines contains the offset of the first character for each line (the first entry is always 0)
 	infos []lineInfo
 }
@@ -116,9 +117,9 @@
 
 // LineCount returns the number of lines in file f.
 func (f *File) LineCount() int {
-	f.set.mutex.RLock()
+	f.mutex.Lock()
 	n := len(f.lines)
-	f.set.mutex.RUnlock()
+	f.mutex.Unlock()
 	return n
 }
 
@@ -127,11 +128,11 @@
 // and smaller than the file size; otherwise the line offset is ignored.
 //
 func (f *File) AddLine(offset int) {
-	f.set.mutex.Lock()
+	f.mutex.Lock()
 	if i := len(f.lines); (i == 0 || f.lines[i-1] < offset) && offset < f.size {
 		f.lines = append(f.lines, offset)
 	}
-	f.set.mutex.Unlock()
+	f.mutex.Unlock()
 }
 
 // MergeLine merges a line with the following line. It is akin to replacing
@@ -143,8 +144,8 @@
 	if line <= 0 {
 		panic("illegal line number (line numbering starts at 1)")
 	}
-	f.set.mutex.Lock()
-	defer f.set.mutex.Unlock()
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
 	if line >= len(f.lines) {
 		panic("illegal line number")
 	}
@@ -176,9 +177,9 @@
 	}
 
 	// set lines table
-	f.set.mutex.Lock()
+	f.mutex.Lock()
 	f.lines = lines
-	f.set.mutex.Unlock()
+	f.mutex.Unlock()
 	return true
 }
 
@@ -198,9 +199,9 @@
 	}
 
 	// set lines table
-	f.set.mutex.Lock()
+	f.mutex.Lock()
 	f.lines = lines
-	f.set.mutex.Unlock()
+	f.mutex.Unlock()
 }
 
 // A lineInfo object describes alternative file and line number
@@ -222,11 +223,11 @@
 // information for //line filename:line comments in source files.
 //
 func (f *File) AddLineInfo(offset int, filename string, line int) {
-	f.set.mutex.Lock()
+	f.mutex.Lock()
 	if i := len(f.infos); i == 0 || f.infos[i-1].Offset < offset && offset < f.size {
 		f.infos = append(f.infos, lineInfo{offset, filename, line})
 	}
-	f.set.mutex.Unlock()
+	f.mutex.Unlock()
 }
 
 // Pos returns the Pos value for the given file offset;
@@ -267,6 +268,8 @@
 // possibly adjusted by //line comments; otherwise those comments are ignored.
 //
 func (f *File) unpack(offset int, adjusted bool) (filename string, line, column int) {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
 	filename = f.name
 	if i := searchInts(f.lines, offset); i >= 0 {
 		line, column = i+1, offset-f.lines[i]+1
@@ -371,7 +374,7 @@
 		panic("illegal base or size")
 	}
 	// base >= s.base && size >= 0
-	f := &File{s, filename, base, size, []int{0}, nil}
+	f := &File{set: s, name: filename, base: base, size: size, lines: []int{0}}
 	base += size + 1 // +1 because EOF also has a position
 	if base < 0 {
 		panic("token.Pos offset overflow (> 2G of source code in file set)")
@@ -446,9 +449,7 @@
 func (s *FileSet) PositionFor(p Pos, adjusted bool) (pos Position) {
 	if p != NoPos {
 		if f := s.file(p); f != nil {
-			s.mutex.RLock()
-			pos = f.position(p, adjusted)
-			s.mutex.RUnlock()
+			return f.position(p, adjusted)
 		}
 	}
 	return
diff --git a/libgo/go/go/token/serialize.go b/libgo/go/go/token/serialize.go
index 4adc8f9..d0ea345 100644
--- a/libgo/go/go/token/serialize.go
+++ b/libgo/go/go/token/serialize.go
@@ -30,7 +30,14 @@
 	files := make([]*File, len(ss.Files))
 	for i := 0; i < len(ss.Files); i++ {
 		f := &ss.Files[i]
-		files[i] = &File{s, f.Name, f.Base, f.Size, f.Lines, f.Infos}
+		files[i] = &File{
+			set:   s,
+			name:  f.Name,
+			base:  f.Base,
+			size:  f.Size,
+			lines: f.Lines,
+			infos: f.Infos,
+		}
 	}
 	s.files = files
 	s.last = nil
@@ -47,7 +54,15 @@
 	ss.Base = s.base
 	files := make([]serializedFile, len(s.files))
 	for i, f := range s.files {
-		files[i] = serializedFile{f.name, f.base, f.size, f.lines, f.infos}
+		f.mutex.Lock()
+		files[i] = serializedFile{
+			Name:  f.name,
+			Base:  f.base,
+			Size:  f.size,
+			Lines: append([]int(nil), f.lines...),
+			Infos: append([]lineInfo(nil), f.infos...),
+		}
+		f.mutex.Unlock()
 	}
 	ss.Files = files
 	s.mutex.Unlock()
diff --git a/libgo/go/go/types/api.go b/libgo/go/go/types/api.go
index 5b911cb..11e7686 100644
--- a/libgo/go/go/types/api.go
+++ b/libgo/go/go/types/api.go
@@ -57,10 +57,9 @@
 // vendored packages. See https://golang.org/s/go15vendor.
 // If possible, external implementations should implement ImporterFrom.
 type Importer interface {
-	// Import returns the imported package for the given import
-	// path, or an error if the package couldn't be imported.
-	// Two calls to Import with the same path return the same
-	// package.
+	// Import returns the imported package for the given import path.
+	// The semantics is like for ImporterFrom.ImportFrom except that
+	// dir and mode are ignored (since they are not present).
 	Import(path string) (*Package, error)
 }
 
@@ -79,12 +78,15 @@
 	Importer
 
 	// ImportFrom returns the imported package for the given import
-	// path when imported by the package in srcDir, or an error
-	// if the package couldn't be imported. The mode value must
-	// be 0; it is reserved for future use.
-	// Two calls to ImportFrom with the same path and srcDir return
-	// the same package.
-	ImportFrom(path, srcDir string, mode ImportMode) (*Package, error)
+	// path when imported by a package file located in dir.
+	// If the import failed, besides returning an error, ImportFrom
+	// is encouraged to cache and return a package anyway, if one
+	// was created. This will reduce package inconsistencies and
+	// follow-on type checker errors due to the missing package.
+	// The mode value must be 0; it is reserved for future use.
+	// Two calls to ImportFrom with the same path and dir must
+	// return the same package.
+	ImportFrom(path, dir string, mode ImportMode) (*Package, error)
 }
 
 // A Config specifies the configuration for type checking.
@@ -99,7 +101,7 @@
 	// identifiers referring to package C (which won't find an object).
 	// This feature is intended for the standard library cmd/api tool.
 	//
-	// Caution: Effects may be unpredictable due to follow-up errors.
+	// Caution: Effects may be unpredictable due to follow-on errors.
 	//          Do not use casually!
 	FakeImportC bool
 
@@ -121,7 +123,7 @@
 	Importer Importer
 
 	// If Sizes != nil, it provides the sizing functions for package unsafe.
-	// Otherwise &StdSizes{WordSize: 8, MaxAlign: 8} is used instead.
+	// Otherwise SizesFor("gc", "amd64") is used instead.
 	Sizes Sizes
 
 	// If DisableUnusedImportCheck is set, packages are not checked
@@ -243,7 +245,7 @@
 // Precondition: the Uses and Defs maps are populated.
 //
 func (info *Info) ObjectOf(id *ast.Ident) Object {
-	if obj, _ := info.Defs[id]; obj != nil {
+	if obj := info.Defs[id]; obj != nil {
 		return obj
 	}
 	return info.Uses[id]
diff --git a/libgo/go/go/types/api_test.go b/libgo/go/go/types/api_test.go
index 818a519..1b17579 100644
--- a/libgo/go/go/types/api_test.go
+++ b/libgo/go/go/types/api_test.go
@@ -1298,154 +1298,73 @@
 	}
 }
 
-// Alias-related code. Keep for now.
-/*
-func TestAliases(t *testing.T) {
-	testenv.MustHaveGoBuild(t)
-
-	const src = `
-package b
-
-import (
-	"./testdata/alias"
-	a "./testdata/alias"
-	"math"
-)
-
-const (
-	c1 = alias.Pi1
-	c2 => a.Pi1
-	c3 => a.Pi2
-	c4 => math.Pi
-)
-
-var (
-	v1 => alias.Default
-	v2 => a.Default
-	v3 = f1
-)
-
-type (
-	t1 => alias.Context
-	t2 => a.Context
-)
-
-func f1 => alias.Sin
-func f2 => a.Sin
-
-func _() {
-	assert(c1 == alias.Pi1 && c2 == a.Pi1 && c3 == a.Pi2 && c4 == math.Pi)
-	assert(c2 == c2 && c2 == c3 && c3 == c4)
-	v1 = v2 // must be assignable
-	var _ *t1 = new(t2) // must be assignable
-	var _ t2 = alias.Default
-	f1(1) // must be callable
-	f2(1)
-	_ = alias.Sin(1)
-	_ = a.Sin(1)
-}
-`
-
-	if out := compile(t, "testdata", "alias.go"); out != "" {
-		defer os.Remove(out)
-	}
-
-	DefPredeclaredTestFuncs() // declare assert built-in for testing
-	mustTypecheck(t, "Aliases", src, nil)
-}
-
-func compile(t *testing.T, dirname, filename string) string {
-	cmd := exec.Command(testenv.GoToolPath(t), "tool", "compile", filename)
-	cmd.Dir = dirname
-	out, err := cmd.CombinedOutput()
-	if err != nil {
-		t.Logf("%s", out)
-		t.Fatalf("go tool compile %s failed: %s", filename, err)
-	}
-	// filename should end with ".go"
-	return filepath.Join(dirname, filename[:len(filename)-2]+"o")
-}
-
-func TestAliasDefUses(t *testing.T) {
+// TestFailedImport tests that we don't get follow-on errors
+// elsewhere in a package due to failing to import a package.
+func TestFailedImport(t *testing.T) {
 	testenv.MustHaveGoBuild(t)
 
 	const src = `
 package p
 
-import(
-	"go/build"
-	"go/types"
-)
+import "foo" // should only see an error here
 
-// Defs
-const Invalid => types.Invalid
-type Struct => types.Struct
-var Default => build.Default
-func Implements => types.Implements
-
-// Uses
-const _ = Invalid
-var _ types.Struct = Struct{} // types must be identical
-var _ build.Context = Default
-var _ = Implements(nil, nil)
+const c = foo.C
+type T = foo.T
+var v T = c
+func f(x T) T { return foo.F(x) }
 `
-
-	info := Info{
-		Defs: make(map[*ast.Ident]Object),
-		Uses: make(map[*ast.Ident]Object),
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "src", src, 0)
+	if err != nil {
+		t.Fatal(err)
 	}
-	mustTypecheck(t, "TestAliasDefUses", src, &info)
+	files := []*ast.File{f}
 
-	// verify Defs
-	defs := map[string]string{
-		"Invalid":    "types.Invalid",
-		"Struct":     "types.Struct",
-		"Default":    "build.Default",
-		"Implements": "types.Implements",
-	}
-
-	for ident, obj := range info.Defs {
-		if alias, ok := obj.(*Alias); ok {
-			if want := defs[ident.Name]; want != "" {
-				orig := alias.Orig()
-				if got := orig.Pkg().Name() + "." + orig.Name(); got != want {
-					t.Errorf("%v: got %v, want %v", ident, got, want)
+	// type-check using all possible importers
+	for _, compiler := range []string{"gc", "gccgo", "source"} {
+		errcount := 0
+		conf := Config{
+			Error: func(err error) {
+				// we should only see the import error
+				if errcount > 0 || !strings.Contains(err.Error(), "could not import foo") {
+					t.Errorf("for %s importer, got unexpected error: %v", compiler, err)
 				}
-				delete(defs, ident.Name) // mark as found
-			} else {
-				t.Errorf("unexpected alias def of %v", ident)
+				errcount++
+			},
+			Importer: importer.For(compiler, nil),
+		}
+
+		info := &Info{
+			Uses: make(map[*ast.Ident]Object),
+		}
+		pkg, _ := conf.Check("p", fset, files, info)
+		if pkg == nil {
+			t.Errorf("for %s importer, type-checking failed to return a package", compiler)
+			continue
+		}
+
+		imports := pkg.Imports()
+		if len(imports) != 1 {
+			t.Errorf("for %s importer, got %d imports, want 1", compiler, len(imports))
+			continue
+		}
+		imp := imports[0]
+		if imp.Name() != "foo" {
+			t.Errorf(`for %s importer, got %q, want "foo"`, compiler, imp.Name())
+			continue
+		}
+
+		// verify that all uses of foo refer to the imported package foo (imp)
+		for ident, obj := range info.Uses {
+			if ident.Name == "foo" {
+				if obj, ok := obj.(*PkgName); ok {
+					if obj.Imported() != imp {
+						t.Errorf("%s resolved to %v; want %v", ident, obj.Imported(), imp)
+					}
+				} else {
+					t.Errorf("%s resolved to %v; want package name", ident, obj)
+				}
 			}
 		}
 	}
-
-	if len(defs) != 0 {
-		t.Errorf("missing aliases: %v", defs)
-	}
-
-	// verify Uses
-	uses := map[string]string{
-		"Invalid":    "types.Invalid",
-		"Struct":     "types.Struct",
-		"Default":    "build.Default",
-		"Implements": "types.Implements",
-	}
-
-	for ident, obj := range info.Uses {
-		if alias, ok := obj.(*Alias); ok {
-			if want := uses[ident.Name]; want != "" {
-				orig := alias.Orig()
-				if got := orig.Pkg().Name() + "." + orig.Name(); got != want {
-					t.Errorf("%v: got %v, want %v", ident, got, want)
-				}
-				delete(uses, ident.Name) // mark as found
-			} else {
-				t.Errorf("unexpected alias use of %v", ident)
-			}
-		}
-	}
-
-	if len(uses) != 0 {
-		t.Errorf("missing aliases: %v", defs)
-	}
 }
-*/
diff --git a/libgo/go/go/types/assignments.go b/libgo/go/go/types/assignments.go
index 18f893d..e5ea071 100644
--- a/libgo/go/go/types/assignments.go
+++ b/libgo/go/go/types/assignments.go
@@ -219,7 +219,7 @@
 			check.errorf(returnPos, "wrong number of return values (want %d, got %d)", l, r)
 			return
 		}
-		check.errorf(rhs[0].Pos(), "assignment count mismatch (%d vs %d)", l, r)
+		check.errorf(rhs[0].Pos(), "cannot initialize %d variables with %d values", l, r)
 		return
 	}
 
@@ -253,7 +253,7 @@
 	}
 	if l != r {
 		check.useGetter(get, r)
-		check.errorf(rhs[0].Pos(), "assignment count mismatch (%d vs %d)", l, r)
+		check.errorf(rhs[0].Pos(), "cannot assign %d values to %d variables", r, l)
 		return
 	}
 
diff --git a/libgo/go/go/types/call.go b/libgo/go/go/types/call.go
index 8e5c537..ffd9629 100644
--- a/libgo/go/go/types/call.go
+++ b/libgo/go/go/types/call.go
@@ -93,7 +93,9 @@
 func (check *Checker) use(arg ...ast.Expr) {
 	var x operand
 	for _, e := range arg {
-		check.rawExpr(&x, e, nil)
+		if e != nil { // be safe
+			check.rawExpr(&x, e, nil)
+		}
 	}
 }
 
@@ -250,7 +252,7 @@
 			check.errorf(ellipsis, "can only use ... with matching parameter")
 			return
 		}
-		if _, ok := x.typ.Underlying().(*Slice); !ok {
+		if _, ok := x.typ.Underlying().(*Slice); !ok && x.typ != Typ[UntypedNil] { // see issue #18268
 			check.errorf(x.pos(), "cannot use %s as parameter of type %s", x, typ)
 			return
 		}
@@ -275,8 +277,6 @@
 	// so we don't need a "package" mode for operands: package names
 	// can only appear in qualified identifiers which are mapped to
 	// selector expressions.
-	// (see also decl.go: checker.aliasDecl)
-	// TODO(gri) factor this code out and share with checker.aliasDecl
 	if ident, ok := e.X.(*ast.Ident); ok {
 		_, obj := check.scope.LookupParent(ident.Name, check.pos)
 		if pname, _ := obj.(*PkgName); pname != nil {
@@ -296,12 +296,6 @@
 				// ok to continue
 			}
 			check.recordUse(e.Sel, exp)
-			exp = original(exp)
-
-			// avoid further errors if the imported object is an alias that's broken
-			if exp == nil {
-				goto Error
-			}
 
 			// Simplified version of the code for *ast.Idents:
 			// - imported objects are always fully initialized
diff --git a/libgo/go/go/types/check.go b/libgo/go/go/types/check.go
index 28e94f1..26db576 100644
--- a/libgo/go/go/types/check.go
+++ b/libgo/go/go/types/check.go
@@ -57,6 +57,16 @@
 	hasCallOrRecv bool           // set if an expression contains a function call or channel receive operation
 }
 
+// An importKey identifies an imported package by import path and source directory
+// (directory containing the file containing the import). In practice, the directory
+// may always be the same, or may not matter. Given an (import path, directory), an
+// importer must always return the same package (but given two different import paths,
+// an importer may still return the same package by mapping them to the same package
+// paths).
+type importKey struct {
+	path, dir string
+}
+
 // A Checker maintains the state of the type checker.
 // It must be created with NewChecker.
 type Checker struct {
@@ -66,7 +76,8 @@
 	fset *token.FileSet
 	pkg  *Package
 	*Info
-	objMap map[Object]*declInfo // maps package-level object to declaration info
+	objMap map[Object]*declInfo   // maps package-level object to declaration info
+	impMap map[importKey]*Package // maps (import path, source directory) to (complete or fake) package
 
 	// information collected during type-checking of a set of package files
 	// (initialized by Files, valid only for the duration of check.Files;
@@ -162,6 +173,7 @@
 		pkg:    pkg,
 		Info:   info,
 		objMap: make(map[Object]*declInfo),
+		impMap: make(map[importKey]*Package),
 	}
 }
 
diff --git a/libgo/go/go/types/check_test.go b/libgo/go/go/types/check_test.go
index f844575..24b3365 100644
--- a/libgo/go/go/types/check_test.go
+++ b/libgo/go/go/types/check_test.go
@@ -68,11 +68,11 @@
 	{"testdata/decls1.src"},
 	{"testdata/decls2a.src", "testdata/decls2b.src"},
 	{"testdata/decls3.src"},
+	{"testdata/decls4.src"},
 	{"testdata/const0.src"},
 	{"testdata/const1.src"},
 	{"testdata/constdecl.src"},
 	{"testdata/vardecl.src"},
-	//{"testdata/aliasdecl.src"},
 	{"testdata/expr0.src"},
 	{"testdata/expr1.src"},
 	{"testdata/expr2.src"},
diff --git a/libgo/go/go/types/decl.go b/libgo/go/go/types/decl.go
index dced7a6..7428f8f 100644
--- a/libgo/go/go/types/decl.go
+++ b/libgo/go/go/types/decl.go
@@ -81,14 +81,10 @@
 		check.varDecl(obj, d.lhs, d.typ, d.init)
 	case *TypeName:
 		// invalid recursive types are detected via path
-		check.typeDecl(obj, d.typ, def, path)
+		check.typeDecl(obj, d.typ, def, path, d.alias)
 	case *Func:
 		// functions may be recursive - no need to track dependencies
 		check.funcDecl(obj, d)
-	// Alias-related code. Keep for now.
-	// case *Alias:
-	// 	// aliases cannot be recursive - no need to track dependencies
-	// 	check.aliasDecl(obj, d)
 	default:
 		unreachable()
 	}
@@ -219,33 +215,42 @@
 	}
 }
 
-func (check *Checker) typeDecl(obj *TypeName, typ ast.Expr, def *Named, path []*TypeName) {
+func (check *Checker) typeDecl(obj *TypeName, typ ast.Expr, def *Named, path []*TypeName, alias bool) {
 	assert(obj.typ == nil)
 
 	// type declarations cannot use iota
 	assert(check.iota == nil)
 
-	named := &Named{obj: obj}
-	def.setUnderlying(named)
-	obj.typ = named // make sure recursive type declarations terminate
+	if alias {
 
-	// determine underlying type of named
-	check.typExpr(typ, named, append(path, obj))
+		obj.typ = Typ[Invalid]
+		obj.typ = check.typExpr(typ, nil, append(path, obj))
 
-	// The underlying type of named may be itself a named type that is
-	// incomplete:
-	//
-	//	type (
-	//		A B
-	//		B *C
-	//		C A
-	//	)
-	//
-	// The type of C is the (named) type of A which is incomplete,
-	// and which has as its underlying type the named type B.
-	// Determine the (final, unnamed) underlying type by resolving
-	// any forward chain (they always end in an unnamed type).
-	named.underlying = underlying(named.underlying)
+	} else {
+
+		named := &Named{obj: obj}
+		def.setUnderlying(named)
+		obj.typ = named // make sure recursive type declarations terminate
+
+		// determine underlying type of named
+		check.typExpr(typ, named, append(path, obj))
+
+		// The underlying type of named may be itself a named type that is
+		// incomplete:
+		//
+		//	type (
+		//		A B
+		//		B *C
+		//		C A
+		//	)
+		//
+		// The type of C is the (named) type of A which is incomplete,
+		// and which has as its underlying type the named type B.
+		// Determine the (final, unnamed) underlying type by resolving
+		// any forward chain (they always end in an unnamed type).
+		named.underlying = underlying(named.underlying)
+
+	}
 
 	// check and add associated methods
 	// TODO(gri) It's easy to create pathological cases where the
@@ -268,21 +273,23 @@
 
 	// spec: "If the base type is a struct type, the non-blank method
 	// and field names must be distinct."
-	base := obj.typ.(*Named)
-	if t, _ := base.underlying.(*Struct); t != nil {
-		for _, fld := range t.fields {
-			if fld.name != "_" {
-				assert(mset.insert(fld) == nil)
+	base, _ := obj.typ.(*Named) // nil if receiver base type is type alias
+	if base != nil {
+		if t, _ := base.underlying.(*Struct); t != nil {
+			for _, fld := range t.fields {
+				if fld.name != "_" {
+					assert(mset.insert(fld) == nil)
+				}
 			}
 		}
-	}
 
-	// Checker.Files may be called multiple times; additional package files
-	// may add methods to already type-checked types. Add pre-existing methods
-	// so that we can detect redeclarations.
-	for _, m := range base.methods {
-		assert(m.name != "_")
-		assert(mset.insert(m) == nil)
+		// Checker.Files may be called multiple times; additional package files
+		// may add methods to already type-checked types. Add pre-existing methods
+		// so that we can detect redeclarations.
+		for _, m := range base.methods {
+			assert(m.name != "_")
+			assert(mset.insert(m) == nil)
+		}
 	}
 
 	// type-check methods
@@ -295,7 +302,7 @@
 				case *Var:
 					check.errorf(m.pos, "field and method with the same name %s", m.name)
 				case *Func:
-					check.errorf(m.pos, "method %s already declared for %s", m.name, base)
+					check.errorf(m.pos, "method %s already declared for %s", m.name, obj)
 				default:
 					unreachable()
 				}
@@ -303,9 +310,12 @@
 				continue
 			}
 		}
+
+		// type-check
 		check.objDecl(m, nil, nil)
+
 		// methods with blank _ names cannot be found - don't keep them
-		if m.name != "_" {
+		if base != nil && m.name != "_" {
 			base.methods = append(base.methods, m)
 		}
 	}
@@ -333,106 +343,6 @@
 	}
 }
 
-// original returns the original Object if obj is an Alias;
-// otherwise it returns obj. The result is never an Alias,
-// but it may be nil.
-func original(obj Object) Object {
-	// an alias stands for the original object; use that one instead
-	if alias, _ := obj.(*disabledAlias); alias != nil {
-		obj = alias.orig
-		// aliases always refer to non-alias originals
-		if _, ok := obj.(*disabledAlias); ok {
-			panic("original is an alias")
-		}
-	}
-	return obj
-}
-
-func (check *Checker) aliasDecl(obj *disabledAlias, decl *declInfo) {
-	assert(obj.typ == nil)
-
-	// alias declarations cannot use iota
-	assert(check.iota == nil)
-
-	// assume alias is invalid to start with
-	obj.typ = Typ[Invalid]
-
-	// rhs must be package-qualified identifer pkg.sel (see also call.go: checker.selector)
-	// TODO(gri) factor this code out and share with checker.selector
-	rhs := decl.init
-	var pkg *Package
-	var sel *ast.Ident
-	if sexpr, ok := rhs.(*ast.SelectorExpr); ok {
-		if ident, ok := sexpr.X.(*ast.Ident); ok {
-			_, obj := check.scope.LookupParent(ident.Name, check.pos)
-			if pname, _ := obj.(*PkgName); pname != nil {
-				assert(pname.pkg == check.pkg)
-				check.recordUse(ident, pname)
-				pname.used = true
-				pkg = pname.imported
-				sel = sexpr.Sel
-			}
-		}
-	}
-	if pkg == nil {
-		check.errorf(rhs.Pos(), "invalid alias: %v is not a package-qualified identifier", rhs)
-		return
-	}
-
-	// qualified identifier must denote an exported object
-	orig := pkg.scope.Lookup(sel.Name)
-	if orig == nil || !orig.Exported() {
-		if !pkg.fake {
-			check.errorf(rhs.Pos(), "%s is not exported by package %s", sel.Name, pkg.name)
-		}
-		return
-	}
-	check.recordUse(sel, orig)
-	orig = original(orig)
-
-	// avoid further errors if the imported object is an alias that's broken
-	if orig == nil {
-		return
-	}
-
-	// An alias declaration must not refer to package unsafe.
-	if orig.Pkg() == Unsafe {
-		check.errorf(rhs.Pos(), "invalid alias: %s refers to package unsafe (%v)", obj.Name(), orig)
-		return
-	}
-
-	// The original must be of the same kind as the alias declaration.
-	var why string
-	switch obj.kind {
-	case token.CONST:
-		if _, ok := orig.(*Const); !ok {
-			why = "constant"
-		}
-	case token.TYPE:
-		if _, ok := orig.(*TypeName); !ok {
-			why = "type"
-		}
-	case token.VAR:
-		if _, ok := orig.(*Var); !ok {
-			why = "variable"
-		}
-	case token.FUNC:
-		if _, ok := orig.(*Func); !ok {
-			why = "function"
-		}
-	default:
-		unreachable()
-	}
-	if why != "" {
-		check.errorf(rhs.Pos(), "invalid alias: %v is not a %s", orig, why)
-		return
-	}
-
-	// alias is valid
-	obj.typ = orig.Type()
-	obj.orig = orig
-}
-
 func (check *Checker) declStmt(decl ast.Decl) {
 	pkg := check.pkg
 
@@ -540,7 +450,7 @@
 				// the innermost containing block."
 				scopePos := s.Name.Pos()
 				check.declare(check.scope, s.Name, obj, scopePos)
-				check.typeDecl(obj, s.Type, nil, nil)
+				check.typeDecl(obj, s.Type, nil, nil, s.Assign.IsValid())
 
 			default:
 				check.invalidAST(s.Pos(), "const, type, or var declaration expected")
diff --git a/libgo/go/go/types/example_test.go b/libgo/go/go/types/example_test.go
index 9daad87..a0c9c21 100644
--- a/libgo/go/go/types/example_test.go
+++ b/libgo/go/go/types/example_test.go
@@ -239,10 +239,10 @@
 	// type S string:
 	//   defined at fib.go:4:6
 	//   used at 6:23
-	// type int int:
+	// type int:
 	//   defined at -
 	//   used at 8:12, 8:17
-	// type string string:
+	// type string:
 	//   defined at -
 	//   used at 4:8
 	// var b S:
diff --git a/libgo/go/go/types/expr.go b/libgo/go/go/types/expr.go
index f76da17..461f0a5 100644
--- a/libgo/go/go/types/expr.go
+++ b/libgo/go/go/types/expr.go
@@ -633,13 +633,13 @@
 	}
 
 	// spec: "The right operand in a shift expression must have unsigned
-	// integer type or be an untyped constant that can be converted to
-	// unsigned integer type."
+	// integer type or be an untyped constant representable by a value of
+	// type uint."
 	switch {
 	case isUnsigned(y.typ):
 		// nothing to do
 	case isUntyped(y.typ):
-		check.convertUntyped(y, Typ[UntypedInt])
+		check.convertUntyped(y, Typ[Uint])
 		if y.mode == invalid {
 			x.mode = invalid
 			return
@@ -800,10 +800,24 @@
 		return
 	}
 
-	if (op == token.QUO || op == token.REM) && (x.mode == constant_ || isInteger(x.typ)) && y.mode == constant_ && constant.Sign(y.val) == 0 {
-		check.invalidOp(y.pos(), "division by zero")
-		x.mode = invalid
-		return
+	if op == token.QUO || op == token.REM {
+		// check for zero divisor
+		if (x.mode == constant_ || isInteger(x.typ)) && y.mode == constant_ && constant.Sign(y.val) == 0 {
+			check.invalidOp(y.pos(), "division by zero")
+			x.mode = invalid
+			return
+		}
+
+		// check for divisor underflow in complex division (see issue 20227)
+		if x.mode == constant_ && y.mode == constant_ && isComplex(x.typ) {
+			re, im := constant.Real(y.val), constant.Imag(y.val)
+			re2, im2 := constant.BinaryOp(re, token.MUL, re), constant.BinaryOp(im, token.MUL, im)
+			if constant.Sign(re2) == 0 && constant.Sign(im2) == 0 {
+				check.invalidOp(y.pos(), "division by zero")
+				x.mode = invalid
+				return
+			}
+		}
 	}
 
 	if x.mode == constant_ && y.mode == constant_ {
@@ -1111,6 +1125,16 @@
 			}
 
 		case *Array:
+			// Prevent crash if the array referred to is not yet set up.
+			// This is a stop-gap solution; a better approach would use the mechanism of
+			// Checker.ident (typexpr.go) using a path of types. But that would require
+			// passing the path everywhere (all expression-checking methods, not just
+			// type expression checking), and we're not set up for that (quite possibly
+			// an indication that cycle detection needs to be rethought). Was issue #18643.
+			if utyp.elem == nil {
+				check.error(e.Pos(), "illegal cycle in type declaration")
+				goto Error
+			}
 			n := check.indexedElts(e.Elts, utyp.elem, utyp.len)
 			// If we have an "open" [...]T array, set the length now that we know it
 			// and record the type for [...] (usually done by check.typExpr which is
@@ -1121,9 +1145,21 @@
 			}
 
 		case *Slice:
+			// Prevent crash if the slice referred to is not yet set up.
+			// See analogous comment for *Array.
+			if utyp.elem == nil {
+				check.error(e.Pos(), "illegal cycle in type declaration")
+				goto Error
+			}
 			check.indexedElts(e.Elts, utyp.elem, -1)
 
 		case *Map:
+			// Prevent crash if the map referred to is not yet set up.
+			// See analogous comment for *Array.
+			if utyp.key == nil || utyp.elem == nil {
+				check.error(e.Pos(), "illegal cycle in type declaration")
+				goto Error
+			}
 			visited := make(map[interface{}][]Type, len(e.Elts))
 			for _, e := range e.Elts {
 				kv, _ := e.(*ast.KeyValueExpr)
@@ -1161,6 +1197,17 @@
 			}
 
 		default:
+			// when "using" all elements unpack KeyValueExpr
+			// explicitly because check.use doesn't accept them
+			for _, e := range e.Elts {
+				if kv, _ := e.(*ast.KeyValueExpr); kv != nil {
+					// Ideally, we should also "use" kv.Key but we can't know
+					// if it's an externally defined struct key or not. Going
+					// forward anyway can lead to other errors. Give up instead.
+					e = kv.Value
+				}
+				check.use(e)
+			}
 			// if utyp is invalid, an error was reported before
 			if utyp != Typ[Invalid] {
 				check.errorf(e.Pos(), "invalid composite literal type %s", typ)
@@ -1182,6 +1229,7 @@
 	case *ast.IndexExpr:
 		check.expr(x, e.X)
 		if x.mode == invalid {
+			check.use(e.Index)
 			goto Error
 		}
 
@@ -1251,6 +1299,7 @@
 	case *ast.SliceExpr:
 		check.expr(x, e.X)
 		if x.mode == invalid {
+			check.use(e.Low, e.High, e.Max)
 			goto Error
 		}
 
diff --git a/libgo/go/go/types/gotype.go b/libgo/go/go/types/gotype.go
index 0a36c08..196fc9b 100644
--- a/libgo/go/go/types/gotype.go
+++ b/libgo/go/go/types/gotype.go
@@ -7,40 +7,46 @@
 // Build this command explicitly: go build gotype.go
 
 /*
-The gotype command does syntactic and semantic analysis of Go files
-and packages like the front-end of a Go compiler. Errors are reported
-if the analysis fails; otherwise gotype is quiet (unless -v is set).
+The gotype command, like the front-end of a Go compiler, parses and
+type-checks a single Go package. Errors are reported if the analysis
+fails; otherwise gotype is quiet (unless -v is set).
 
 Without a list of paths, gotype reads from standard input, which
 must provide a single Go source file defining a complete package.
 
-If a single path is specified that is a directory, gotype checks
-the Go files in that directory; they must all belong to the same
-package.
+With a single directory argument, gotype checks the Go files in
+that directory, comprising a single package. Use -t to include the
+(in-package) _test.go files. Use -x to type check only external
+test files.
 
-Otherwise, each path must be the filename of Go file belonging to
-the same package.
+Otherwise, each path must be the filename of a Go file belonging
+to the same package.
+
+Imports are processed by importing directly from the source of
+imported packages (default), or by importing from compiled and
+installed packages (by setting -c to the respective compiler).
+
+The -c flag must be set to a compiler ("gc", "gccgo") when type-
+checking packages containing imports with relative import paths
+(import "./mypkg") because the source importer cannot know which
+files to include for such packages.
 
 Usage:
 	gotype [flags] [path...]
 
 The flags are:
-	-a
-		use all (incl. _test.go) files when processing a directory
+	-t
+		include local test files in a directory (ignored if -x is provided)
+	-x
+		consider only external test files in a directory
 	-e
 		report all errors (not just the first 10)
 	-v
 		verbose mode
 	-c
-		compiler used to compile packages (gc or gccgo); default: gc
-		(gotype based on Go1.5 and up only)
-	-gccgo
-		use gccimporter instead of gcimporter
-		(gotype based on Go1.4 and before only)
+		compiler used for installed packages (gc, gccgo, or source); default: source
 
-Debugging flags:
-	-seq
-		parse sequentially, rather than in parallel
+Flags controlling additional output:
 	-ast
 		print AST (forces -seq)
 	-trace
@@ -54,13 +60,14 @@
 
 	gotype a.go b.go c.go
 
-To check an entire package in the directory dir and print the processed files:
+To check an entire package including (in-package) tests in the directory dir and print the processed files:
 
-	gotype -v dir
+	gotype -t -v dir
 
-To check an entire package including tests in the local directory:
+To check the external test package (if any) in the current directory, based on installed packages compiled with
+cmd/compile:
 
-	gotype -a .
+	gotype -c=gc -x .
 
 To verify the output of a pipe:
 
@@ -82,18 +89,19 @@
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"sync"
 	"time"
 )
 
 var (
 	// main operation modes
-	allFiles  = flag.Bool("a", false, "use all (incl. _test.go) files when processing a directory")
-	allErrors = flag.Bool("e", false, "report all errors (not just the first 10)")
-	verbose   = flag.Bool("v", false, "verbose mode")
-	gccgo     = flag.Bool("gccgo", false, "use gccgoimporter instead of gcimporter")
+	testFiles  = flag.Bool("t", false, "include in-package test files in a directory")
+	xtestFiles = flag.Bool("x", false, "consider only external test files in a directory")
+	allErrors  = flag.Bool("e", false, "report all errors, not just the first 10")
+	verbose    = flag.Bool("v", false, "verbose mode")
+	compiler   = flag.String("c", "source", "compiler used for installed packages (gc, gccgo, or source)")
 
-	// debugging support
-	sequential    = flag.Bool("seq", false, "parse sequentially, rather than in parallel")
+	// additional output control
 	printAST      = flag.Bool("ast", false, "print AST (forces -seq)")
 	printTrace    = flag.Bool("trace", false, "print parse trace (forces -seq)")
 	parseComments = flag.Bool("comments", false, "parse comments (ignored unless -ast or -trace is provided)")
@@ -102,36 +110,55 @@
 var (
 	fset       = token.NewFileSet()
 	errorCount = 0
+	sequential = false
 	parserMode parser.Mode
-	sizes      types.Sizes
 )
 
 func initParserMode() {
 	if *allErrors {
 		parserMode |= parser.AllErrors
 	}
+	if *printAST {
+		sequential = true
+	}
 	if *printTrace {
 		parserMode |= parser.Trace
+		sequential = true
 	}
 	if *parseComments && (*printAST || *printTrace) {
 		parserMode |= parser.ParseComments
 	}
 }
 
-func initSizes() {
-	wordSize := 8
-	maxAlign := 8
-	switch build.Default.GOARCH {
-	case "386", "arm":
-		wordSize = 4
-		maxAlign = 4
-		// add more cases as needed
-	}
-	sizes = &types.StdSizes{WordSize: int64(wordSize), MaxAlign: int64(maxAlign)}
-}
+const usageString = `usage: gotype [flags] [path ...]
+
+The gotype command, like the front-end of a Go compiler, parses and
+type-checks a single Go package. Errors are reported if the analysis
+fails; otherwise gotype is quiet (unless -v is set).
+
+Without a list of paths, gotype reads from standard input, which
+must provide a single Go source file defining a complete package.
+
+With a single directory argument, gotype checks the Go files in
+that directory, comprising a single package. Use -t to include the
+(in-package) _test.go files. Use -x to type check only external
+test files.
+
+Otherwise, each path must be the filename of a Go file belonging
+to the same package.
+
+Imports are processed by importing directly from the source of
+imported packages (default), or by importing from compiled and
+installed packages (by setting -c to the respective compiler).
+
+The -c flag must be set to a compiler ("gc", "gccgo") when type-
+checking packages containing imports with relative import paths
+(import "./mypkg") because the source importer cannot know which
+files to include for such packages.
+`
 
 func usage() {
-	fmt.Fprintln(os.Stderr, "usage: gotype [flags] [path ...]")
+	fmt.Fprintln(os.Stderr, usageString)
 	flag.PrintDefaults()
 	os.Exit(2)
 }
@@ -165,60 +192,49 @@
 	return parse("<standard input>", src)
 }
 
-func parseFiles(filenames []string) ([]*ast.File, error) {
+func parseFiles(dir string, filenames []string) ([]*ast.File, error) {
 	files := make([]*ast.File, len(filenames))
+	errors := make([]error, len(filenames))
 
-	if *sequential {
-		for i, filename := range filenames {
-			var err error
-			files[i], err = parse(filename, nil)
-			if err != nil {
-				return nil, err // leave unfinished goroutines hanging
-			}
+	var wg sync.WaitGroup
+	for i, filename := range filenames {
+		wg.Add(1)
+		go func(i int, filepath string) {
+			defer wg.Done()
+			files[i], errors[i] = parse(filepath, nil)
+		}(i, filepath.Join(dir, filename))
+		if sequential {
+			wg.Wait()
 		}
-	} else {
-		type parseResult struct {
-			file *ast.File
-			err  error
-		}
+	}
+	wg.Wait()
 
-		out := make(chan parseResult)
-		for _, filename := range filenames {
-			go func(filename string) {
-				file, err := parse(filename, nil)
-				out <- parseResult{file, err}
-			}(filename)
-		}
-
-		for i := range filenames {
-			res := <-out
-			if res.err != nil {
-				return nil, res.err // leave unfinished goroutines hanging
-			}
-			files[i] = res.file
+	// if there are errors, return the first one for deterministic results
+	for _, err := range errors {
+		if err != nil {
+			return nil, err
 		}
 	}
 
 	return files, nil
 }
 
-func parseDir(dirname string) ([]*ast.File, error) {
+func parseDir(dir string) ([]*ast.File, error) {
 	ctxt := build.Default
-	pkginfo, err := ctxt.ImportDir(dirname, 0)
+	pkginfo, err := ctxt.ImportDir(dir, 0)
 	if _, nogo := err.(*build.NoGoError); err != nil && !nogo {
 		return nil, err
 	}
+
+	if *xtestFiles {
+		return parseFiles(dir, pkginfo.XTestGoFiles)
+	}
+
 	filenames := append(pkginfo.GoFiles, pkginfo.CgoFiles...)
-	if *allFiles {
+	if *testFiles {
 		filenames = append(filenames, pkginfo.TestGoFiles...)
 	}
-
-	// complete file names
-	for i, filename := range filenames {
-		filenames[i] = filepath.Join(dirname, filename)
-	}
-
-	return parseFiles(filenames)
+	return parseFiles(dir, filenames)
 }
 
 func getPkgFiles(args []string) ([]*ast.File, error) {
@@ -244,15 +260,13 @@
 	}
 
 	// list of files
-	return parseFiles(args)
+	return parseFiles("", args)
 }
 
 func checkPkgFiles(files []*ast.File) {
-	compiler := "gc"
-	if *gccgo {
-		compiler = "gccgo"
-	}
 	type bailout struct{}
+
+	// if checkPkgFiles is called multiple times, set up conf only once
 	conf := types.Config{
 		FakeImportC: true,
 		Error: func(err error) {
@@ -261,8 +275,8 @@
 			}
 			report(err)
 		},
-		Importer: importer.For(compiler, nil),
-		Sizes:    sizes,
+		Importer: importer.For(*compiler, nil),
+		Sizes:    types.SizesFor(build.Default.Compiler, build.Default.GOARCH),
 	}
 
 	defer func() {
@@ -297,11 +311,7 @@
 func main() {
 	flag.Usage = usage
 	flag.Parse()
-	if *printAST || *printTrace {
-		*sequential = true
-	}
 	initParserMode()
-	initSizes()
 
 	start := time.Now()
 
diff --git a/libgo/go/go/types/hilbert_test.go b/libgo/go/go/types/hilbert_test.go
index 07d5a63..500fd27 100644
--- a/libgo/go/go/types/hilbert_test.go
+++ b/libgo/go/go/types/hilbert_test.go
@@ -52,8 +52,7 @@
 func program(n int, out string) []byte {
 	var g gen
 
-	g.p(`// WARNING: GENERATED FILE - DO NOT MODIFY MANUALLY!
-// (To generate, in go/types directory: go test -run=Hilbert -H=%d -out=%q)
+	g.p(`// Code generated by: go test -run=Hilbert -H=%d -out=%q. DO NOT EDIT.
 
 // This program tests arbitrary precision constant arithmetic
 // by generating the constant elements of a Hilbert matrix H,
diff --git a/libgo/go/go/types/lookup.go b/libgo/go/go/types/lookup.go
index 3caca55..ee8202d 100644
--- a/libgo/go/go/types/lookup.go
+++ b/libgo/go/go/types/lookup.go
@@ -67,24 +67,22 @@
 	}
 
 	typ, isPtr := deref(T)
-	named, _ := typ.(*Named)
 
 	// *typ where typ is an interface has no methods.
-	if isPtr {
-		utyp := typ
-		if named != nil {
-			utyp = named.underlying
-		}
-		if _, ok := utyp.(*Interface); ok {
-			return
-		}
+	if isPtr && IsInterface(typ) {
+		return
 	}
 
 	// Start with typ as single entry at shallowest depth.
-	// If typ is not a named type, insert a nil type instead.
-	current := []embeddedType{{named, nil, isPtr, false}}
+	current := []embeddedType{{typ, nil, isPtr, false}}
 
-	// named types that we have seen already, allocated lazily
+	// Named types that we have seen already, allocated lazily.
+	// Used to avoid endless searches in case of recursive types.
+	// Since only Named types can be used for recursive types, we
+	// only need to track those.
+	// (If we ever allow type aliases to construct recursive types,
+	// we must use type identity rather than pointer equality for
+	// the map key comparison, as we do in consolidateMultiples.)
 	var seen map[*Named]bool
 
 	// search current depth
@@ -93,11 +91,12 @@
 
 		// look for (pkg, name) in all types at current depth
 		for _, e := range current {
-			// The very first time only, e.typ may be nil.
-			// In this case, we don't have a named type and
-			// we simply continue with the underlying type.
-			if e.typ != nil {
-				if seen[e.typ] {
+			typ := e.typ
+
+			// If we have a named type, we may have associated methods.
+			// Look for those first.
+			if named, _ := typ.(*Named); named != nil {
+				if seen[named] {
 					// We have seen this type before, at a more shallow depth
 					// (note that multiples of this type at the current depth
 					// were consolidated before). The type at that depth shadows
@@ -108,10 +107,10 @@
 				if seen == nil {
 					seen = make(map[*Named]bool)
 				}
-				seen[e.typ] = true
+				seen[named] = true
 
 				// look for a matching attached method
-				if i, m := lookupMethod(e.typ.methods, pkg, name); m != nil {
+				if i, m := lookupMethod(named.methods, pkg, name); m != nil {
 					// potential match
 					assert(m.typ != nil)
 					index = concat(e.index, i)
@@ -124,7 +123,7 @@
 				}
 
 				// continue with underlying type
-				typ = e.typ.underlying
+				typ = named.underlying
 			}
 
 			switch t := typ.(type) {
@@ -147,16 +146,15 @@
 					// we have a name collision on the same depth; in either
 					// case we don't need to look further).
 					// Embedded fields are always of the form T or *T where
-					// T is a named type. If e.typ appeared multiple times at
+					// T is a type name. If e.typ appeared multiple times at
 					// this depth, f.typ appears multiple times at the next
 					// depth.
 					if obj == nil && f.anonymous {
-						// Ignore embedded basic types - only user-defined
-						// named types can have methods or struct fields.
 						typ, isPtr := deref(f.typ)
-						if t, _ := typ.(*Named); t != nil {
-							next = append(next, embeddedType{t, concat(e.index, i), e.indirect || isPtr, e.multiples})
-						}
+						// TODO(gri) optimization: ignore types that can't
+						// have fields or methods (only Named, Struct, and
+						// Interface types need to be considered).
+						next = append(next, embeddedType{typ, concat(e.index, i), e.indirect || isPtr, e.multiples})
 					}
 				}
 
@@ -193,12 +191,12 @@
 	return nil, nil, false // not found
 }
 
-// embeddedType represents an embedded named type
+// embeddedType represents an embedded type
 type embeddedType struct {
-	typ       *Named // nil means use the outer typ variable instead
-	index     []int  // embedded field indices, starting with index at depth 0
-	indirect  bool   // if set, there was a pointer indirection on the path to this field
-	multiples bool   // if set, typ appears multiple times at this depth
+	typ       Type
+	index     []int // embedded field indices, starting with index at depth 0
+	indirect  bool  // if set, there was a pointer indirection on the path to this field
+	multiples bool  // if set, typ appears multiple times at this depth
 }
 
 // consolidateMultiples collects multiple list entries with the same type
@@ -209,10 +207,10 @@
 		return list // at most one entry - nothing to do
 	}
 
-	n := 0                       // number of entries w/ unique type
-	prev := make(map[*Named]int) // index at which type was previously seen
+	n := 0                     // number of entries w/ unique type
+	prev := make(map[Type]int) // index at which type was previously seen
 	for _, e := range list {
-		if i, found := prev[e.typ]; found {
+		if i, found := lookupType(prev, e.typ); found {
 			list[i].multiples = true
 			// ignore this entry
 		} else {
@@ -224,6 +222,21 @@
 	return list[:n]
 }
 
+func lookupType(m map[Type]int, typ Type) (int, bool) {
+	// fast path: maybe the types are equal
+	if i, found := m[typ]; found {
+		return i, true
+	}
+
+	for t, i := range m {
+		if Identical(t, typ) {
+			return i, true
+		}
+	}
+
+	return 0, false
+}
+
 // MissingMethod returns (nil, false) if V implements T, otherwise it
 // returns a missing method required by T and whether it is missing or
 // just has the wrong type.
diff --git a/libgo/go/go/types/methodset.go b/libgo/go/go/types/methodset.go
index b27f2da..4f791d9 100644
--- a/libgo/go/go/types/methodset.go
+++ b/libgo/go/go/types/methodset.go
@@ -72,24 +72,22 @@
 	var base methodSet
 
 	typ, isPtr := deref(T)
-	named, _ := typ.(*Named)
 
 	// *typ where typ is an interface has no methods.
-	if isPtr {
-		utyp := typ
-		if named != nil {
-			utyp = named.underlying
-		}
-		if _, ok := utyp.(*Interface); ok {
-			return &emptyMethodSet
-		}
+	if isPtr && IsInterface(typ) {
+		return &emptyMethodSet
 	}
 
 	// Start with typ as single entry at shallowest depth.
-	// If typ is not a named type, insert a nil type instead.
-	current := []embeddedType{{named, nil, isPtr, false}}
+	current := []embeddedType{{typ, nil, isPtr, false}}
 
-	// named types that we have seen already, allocated lazily
+	// Named types that we have seen already, allocated lazily.
+	// Used to avoid endless searches in case of recursive types.
+	// Since only Named types can be used for recursive types, we
+	// only need to track those.
+	// (If we ever allow type aliases to construct recursive types,
+	// we must use type identity rather than pointer equality for
+	// the map key comparison, as we do in consolidateMultiples.)
 	var seen map[*Named]bool
 
 	// collect methods at current depth
@@ -101,11 +99,12 @@
 		var mset methodSet
 
 		for _, e := range current {
-			// The very first time only, e.typ may be nil.
-			// In this case, we don't have a named type and
-			// we simply continue with the underlying type.
-			if e.typ != nil {
-				if seen[e.typ] {
+			typ := e.typ
+
+			// If we have a named type, we may have associated methods.
+			// Look for those first.
+			if named, _ := typ.(*Named); named != nil {
+				if seen[named] {
 					// We have seen this type before, at a more shallow depth
 					// (note that multiples of this type at the current depth
 					// were consolidated before). The type at that depth shadows
@@ -116,12 +115,12 @@
 				if seen == nil {
 					seen = make(map[*Named]bool)
 				}
-				seen[e.typ] = true
+				seen[named] = true
 
-				mset = mset.add(e.typ.methods, e.index, e.indirect, e.multiples)
+				mset = mset.add(named.methods, e.index, e.indirect, e.multiples)
 
 				// continue with underlying type
-				typ = e.typ.underlying
+				typ = named.underlying
 			}
 
 			switch t := typ.(type) {
@@ -130,16 +129,15 @@
 					fset = fset.add(f, e.multiples)
 
 					// Embedded fields are always of the form T or *T where
-					// T is a named type. If typ appeared multiple times at
+					// T is a type name. If typ appeared multiple times at
 					// this depth, f.Type appears multiple times at the next
 					// depth.
 					if f.anonymous {
-						// Ignore embedded basic types - only user-defined
-						// named types can have methods or struct fields.
 						typ, isPtr := deref(f.typ)
-						if t, _ := typ.(*Named); t != nil {
-							next = append(next, embeddedType{t, concat(e.index, i), e.indirect || isPtr, e.multiples})
-						}
+						// TODO(gri) optimization: ignore types that can't
+						// have fields or methods (only Named, Struct, and
+						// Interface types need to be considered).
+						next = append(next, embeddedType{typ, concat(e.index, i), e.indirect || isPtr, e.multiples})
 					}
 				}
 
diff --git a/libgo/go/go/types/object.go b/libgo/go/go/types/object.go
index 6c0c5c4..f0bcd67 100644
--- a/libgo/go/go/types/object.go
+++ b/libgo/go/go/types/object.go
@@ -25,7 +25,7 @@
 	Name() string   // package local object name
 	Type() Type     // object type
 	Exported() bool // reports whether the name starts with a capital letter
-	Id() string     // object id (see Id below)
+	Id() string     // object name if exported, qualified name if not exported (see func Id)
 
 	// String returns a human-readable string of the object.
 	String() string
@@ -64,15 +64,10 @@
 	// inside a package and outside a package - which breaks some
 	// tests)
 	path := "_"
-	// TODO(gri): shouldn't !ast.IsExported(name) => pkg != nil be an precondition?
-	// if pkg == nil {
-	// 	panic("nil package in lookup of unexported name")
-	// }
-	if pkg != nil {
+	// pkg is nil for objects in Universe scope and possibly types
+	// introduced via Eval (see also comment in object.sameId)
+	if pkg != nil && pkg.path != "" {
 		path = pkg.path
-		if path == "" {
-			path = "_"
-		}
 	}
 	return path + "." + name
 }
@@ -154,7 +149,7 @@
 func (obj *Const) Val() constant.Value { return obj.val }
 func (*Const) isDependency()           {} // a constant may be a dependency of an initialization expression
 
-// A TypeName represents a declared type.
+// A TypeName represents a name for a (named or alias) type.
 type TypeName struct {
 	object
 }
@@ -163,6 +158,30 @@
 	return &TypeName{object{nil, pos, pkg, name, typ, 0, token.NoPos}}
 }
 
+// IsAlias reports whether obj is an alias name for a type.
+func (obj *TypeName) IsAlias() bool {
+	switch t := obj.typ.(type) {
+	case nil:
+		return false
+	case *Basic:
+		// unsafe.Pointer is not an alias.
+		if obj.pkg == Unsafe {
+			return false
+		}
+		// Any user-defined type name for a basic type is an alias for a
+		// basic type (because basic types are pre-declared in the Universe
+		// scope, outside any package scope), and so is any type name with
+		// a different name than the name of the basic type it refers to.
+		// Additionally, we need to look for "byte" and "rune" because they
+		// are aliases but have the same names (for better error messages).
+		return obj.pkg != nil || t.name != obj.name || t == universeByte || t == universeRune
+	case *Named:
+		return obj != t.obj
+	default:
+		return true
+	}
+}
+
 // A Variable represents a declared variable (including function parameters and results, and struct fields).
 type Var struct {
 	object
@@ -215,28 +234,6 @@
 func (obj *Func) Scope() *Scope { return obj.typ.(*Signature).scope }
 func (*Func) isDependency()     {} // a function may be a dependency of an initialization expression
 
-// An Alias represents a declared alias.
-type disabledAlias struct {
-	object
-	orig Object      // aliased constant, type, variable, or function; never an alias
-	kind token.Token // token.CONST, token.TYPE, token.VAR, or token.FUNC (only needed during resolve phase)
-}
-
-func disabledNewAlias(pos token.Pos, pkg *Package, name string, orig Object) *disabledAlias {
-	var typ Type = Typ[Invalid]
-	if orig != nil {
-		typ = orig.Type()
-	}
-	// No need to set a valid Alias.kind - that field is only used during identifier
-	// resolution (1st type-checker pass). We could store the field outside but it's
-	// easier to keep it here.
-	return &disabledAlias{object{nil, pos, pkg, name, typ, 0, token.NoPos}, orig, token.ILLEGAL}
-}
-
-// Orig returns the aliased object, or nil if there was an error.
-// The returned object is never an Alias.
-func (obj *disabledAlias) disabledOrig() Object { return obj.orig }
-
 // A Label represents a declared label.
 type Label struct {
 	object
@@ -264,7 +261,9 @@
 }
 
 func writeObject(buf *bytes.Buffer, obj Object, qf Qualifier) {
+	var tname *TypeName
 	typ := obj.Type()
+
 	switch obj := obj.(type) {
 	case *PkgName:
 		fmt.Fprintf(buf, "package %s", obj.Name())
@@ -277,8 +276,8 @@
 		buf.WriteString("const")
 
 	case *TypeName:
+		tname = obj
 		buf.WriteString("type")
-		typ = typ.Underlying()
 
 	case *Var:
 		if obj.isField {
@@ -295,10 +294,6 @@
 		}
 		return
 
-	// Alias-related code. Keep for now.
-	// case *Alias:
-	// 	buf.WriteString("alias")
-
 	case *Label:
 		buf.WriteString("label")
 		typ = nil
@@ -322,10 +317,27 @@
 		writePackage(buf, obj.Pkg(), qf)
 	}
 	buf.WriteString(obj.Name())
-	if typ != nil {
-		buf.WriteByte(' ')
-		WriteType(buf, typ, qf)
+
+	if typ == nil {
+		return
 	}
+
+	if tname != nil {
+		// We have a type object: Don't print anything more for
+		// basic types since there's no more information (names
+		// are the same; see also comment in TypeName.IsAlias).
+		if _, ok := typ.(*Basic); ok {
+			return
+		}
+		if tname.IsAlias() {
+			buf.WriteString(" =")
+		} else {
+			typ = typ.Underlying()
+		}
+	}
+
+	buf.WriteByte(' ')
+	WriteType(buf, typ, qf)
 }
 
 func writePackage(buf *bytes.Buffer, pkg *Package, qf Qualifier) {
@@ -353,15 +365,14 @@
 	return buf.String()
 }
 
-func (obj *PkgName) String() string       { return ObjectString(obj, nil) }
-func (obj *Const) String() string         { return ObjectString(obj, nil) }
-func (obj *TypeName) String() string      { return ObjectString(obj, nil) }
-func (obj *Var) String() string           { return ObjectString(obj, nil) }
-func (obj *Func) String() string          { return ObjectString(obj, nil) }
-func (obj *disabledAlias) String() string { return ObjectString(obj, nil) }
-func (obj *Label) String() string         { return ObjectString(obj, nil) }
-func (obj *Builtin) String() string       { return ObjectString(obj, nil) }
-func (obj *Nil) String() string           { return ObjectString(obj, nil) }
+func (obj *PkgName) String() string  { return ObjectString(obj, nil) }
+func (obj *Const) String() string    { return ObjectString(obj, nil) }
+func (obj *TypeName) String() string { return ObjectString(obj, nil) }
+func (obj *Var) String() string      { return ObjectString(obj, nil) }
+func (obj *Func) String() string     { return ObjectString(obj, nil) }
+func (obj *Label) String() string    { return ObjectString(obj, nil) }
+func (obj *Builtin) String() string  { return ObjectString(obj, nil) }
+func (obj *Nil) String() string      { return ObjectString(obj, nil) }
 
 func writeFuncName(buf *bytes.Buffer, f *Func, qf Qualifier) {
 	if f.typ != nil {
diff --git a/libgo/go/go/types/object_test.go b/libgo/go/go/types/object_test.go
new file mode 100644
index 0000000..b0acdd9
--- /dev/null
+++ b/libgo/go/go/types/object_test.go
@@ -0,0 +1,44 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import "testing"
+
+func TestIsAlias(t *testing.T) {
+	check := func(obj *TypeName, want bool) {
+		if got := obj.IsAlias(); got != want {
+			t.Errorf("%v: got IsAlias = %v; want %v", obj, got, want)
+		}
+	}
+
+	// predeclared types
+	check(Unsafe.Scope().Lookup("Pointer").(*TypeName), false)
+	for _, name := range Universe.Names() {
+		if obj, _ := Universe.Lookup(name).(*TypeName); obj != nil {
+			check(obj, name == "byte" || name == "rune")
+		}
+	}
+
+	// various other types
+	pkg := NewPackage("p", "p")
+	t1 := NewTypeName(0, pkg, "t1", nil)
+	n1 := NewNamed(t1, new(Struct), nil)
+	for _, test := range []struct {
+		name  *TypeName
+		alias bool
+	}{
+		{NewTypeName(0, nil, "t0", nil), false}, // no type yet
+		{NewTypeName(0, pkg, "t0", nil), false}, // no type yet
+		{t1, false},                             // type name refers to named type and vice versa
+		{NewTypeName(0, nil, "t2", new(Interface)), true}, // type name refers to unnamed type
+		{NewTypeName(0, pkg, "t3", n1), true},             // type name refers to named type with different type name
+		{NewTypeName(0, nil, "t4", Typ[Int32]), true},     // type name refers to basic type with different name
+		{NewTypeName(0, nil, "int32", Typ[Int32]), false}, // type name refers to basic type with same name
+		{NewTypeName(0, pkg, "int32", Typ[Int32]), true},  // type name is declared in user-defined package (outside Universe)
+		{NewTypeName(0, nil, "rune", Typ[Rune]), true},    // type name refers to basic type rune which is an alias already
+	} {
+		check(test.name, test.alias)
+	}
+}
diff --git a/libgo/go/go/types/operand.go b/libgo/go/go/types/operand.go
index b2f16b6..07247bd 100644
--- a/libgo/go/go/types/operand.go
+++ b/libgo/go/go/types/operand.go
@@ -122,13 +122,15 @@
 	case invalid, novalue, builtin, typexpr:
 		// no type
 	default:
-		// has type
-		if isUntyped(x.typ) {
-			buf.WriteString(x.typ.(*Basic).name)
-			buf.WriteByte(' ')
-			break
+		// should have a type, but be cautious (don't crash during printing)
+		if x.typ != nil {
+			if isUntyped(x.typ) {
+				buf.WriteString(x.typ.(*Basic).name)
+				buf.WriteByte(' ')
+				break
+			}
+			hasType = true
 		}
-		hasType = true
 	}
 
 	// <mode>
diff --git a/libgo/go/go/types/package.go b/libgo/go/go/types/package.go
index a588ee7..cd202a0 100644
--- a/libgo/go/go/types/package.go
+++ b/libgo/go/go/types/package.go
@@ -19,13 +19,9 @@
 	fake     bool // scope lookup errors are silently dropped if package is fake (internal use only)
 }
 
-// NewPackage returns a new Package for the given package path and name;
-// the name must not be the blank identifier.
+// NewPackage returns a new Package for the given package path and name.
 // The package is not complete and contains no explicit imports.
 func NewPackage(path, name string) *Package {
-	if name == "_" {
-		panic("invalid package name _")
-	}
 	scope := NewScope(Universe, token.NoPos, token.NoPos, fmt.Sprintf("package %q", path))
 	return &Package{path: path, name: name, scope: scope}
 }
@@ -52,7 +48,7 @@
 func (pkg *Package) MarkComplete() { pkg.complete = true }
 
 // Imports returns the list of packages directly imported by
-// pkg; the list is in source order. Package unsafe is excluded.
+// pkg; the list is in source order.
 //
 // If pkg was loaded from export data, Imports includes packages that
 // provide package-level objects referenced by pkg. This may be more or
diff --git a/libgo/go/go/types/predicates.go b/libgo/go/go/types/predicates.go
index 21fd81e..c3b87dd 100644
--- a/libgo/go/go/types/predicates.go
+++ b/libgo/go/go/types/predicates.go
@@ -139,7 +139,7 @@
 	case *Basic:
 		// Basic types are singletons except for the rune and byte
 		// aliases, thus we cannot solely rely on the x == y check
-		// above.
+		// above. See also comment in TypeName.IsAlias.
 		if y, ok := y.(*Basic); ok {
 			return x.kind == y.kind
 		}
diff --git a/libgo/go/go/types/resolver.go b/libgo/go/go/types/resolver.go
index 046e147..05603b3 100644
--- a/libgo/go/go/types/resolver.go
+++ b/libgo/go/go/types/resolver.go
@@ -14,13 +14,14 @@
 	"unicode"
 )
 
-// A declInfo describes a package-level const, type, var, func, or alias declaration.
+// A declInfo describes a package-level const, type, var, or func declaration.
 type declInfo struct {
 	file  *Scope        // scope of file containing this declaration
 	lhs   []*Var        // lhs of n:1 variable declarations, or nil
 	typ   ast.Expr      // type, or nil
 	init  ast.Expr      // init/orig expression, or nil
 	fdecl *ast.FuncDecl // func declaration, or nil
+	alias bool          // type alias declaration
 
 	// The deps field tracks initialization expression dependencies.
 	// As a special (overloaded) case, it also tracks dependencies of
@@ -124,6 +125,73 @@
 	return fmt.Sprintf("file[%d]", fileNo)
 }
 
+func (check *Checker) importPackage(pos token.Pos, path, dir string) *Package {
+	// If we already have a package for the given (path, dir)
+	// pair, use it instead of doing a full import.
+	// Checker.impMap only caches packages that are marked Complete
+	// or fake (dummy packages for failed imports). Incomplete but
+	// non-fake packages do require an import to complete them.
+	key := importKey{path, dir}
+	imp := check.impMap[key]
+	if imp != nil {
+		return imp
+	}
+
+	// no package yet => import it
+	if path == "C" && check.conf.FakeImportC {
+		imp = NewPackage("C", "C")
+		imp.fake = true
+	} else {
+		// ordinary import
+		var err error
+		if importer := check.conf.Importer; importer == nil {
+			err = fmt.Errorf("Config.Importer not installed")
+		} else if importerFrom, ok := importer.(ImporterFrom); ok {
+			imp, err = importerFrom.ImportFrom(path, dir, 0)
+			if imp == nil && err == nil {
+				err = fmt.Errorf("Config.Importer.ImportFrom(%s, %s, 0) returned nil but no error", path, dir)
+			}
+		} else {
+			imp, err = importer.Import(path)
+			if imp == nil && err == nil {
+				err = fmt.Errorf("Config.Importer.Import(%s) returned nil but no error", path)
+			}
+		}
+		// make sure we have a valid package name
+		// (errors here can only happen through manipulation of packages after creation)
+		if err == nil && imp != nil && (imp.name == "_" || imp.name == "") {
+			err = fmt.Errorf("invalid package name: %q", imp.name)
+			imp = nil // create fake package below
+		}
+		if err != nil {
+			check.errorf(pos, "could not import %s (%s)", path, err)
+			if imp == nil {
+				// create a new fake package
+				// come up with a sensible package name (heuristic)
+				name := path
+				if i := len(name); i > 0 && name[i-1] == '/' {
+					name = name[:i-1]
+				}
+				if i := strings.LastIndex(name, "/"); i >= 0 {
+					name = name[i+1:]
+				}
+				imp = NewPackage(path, name)
+			}
+			// continue to use the package as best as we can
+			imp.fake = true // avoid follow-up lookup failures
+		}
+	}
+
+	// package should be complete or marked fake, but be cautious
+	if imp.complete || imp.fake {
+		check.impMap[key] = imp
+		return imp
+	}
+
+	// something went wrong (importer may have returned incomplete package without error)
+	return nil
+}
+
 // collectObjects collects all file and package objects and inserts them
 // into their respective scopes. It also performs imports and associates
 // methods with receiver base type names.
@@ -133,25 +201,14 @@
 	// pkgImports is the set of packages already imported by any package file seen
 	// so far. Used to avoid duplicate entries in pkg.imports. Allocate and populate
 	// it (pkg.imports may not be empty if we are checking test files incrementally).
+	// Note that pkgImports is keyed by package (and thus package path), not by an
+	// importKey value. Two different importKey values may map to the same package
+	// which is why we cannot use the check.impMap here.
 	var pkgImports = make(map[*Package]bool)
 	for _, imp := range pkg.imports {
 		pkgImports[imp] = true
 	}
 
-	// srcDir is the directory used by the Importer to look up packages.
-	// The typechecker itself doesn't need this information so it is not
-	// explicitly provided. Instead, we extract it from position info of
-	// the source files as needed.
-	// This is the only place where the type-checker (just the importer)
-	// needs to know the actual source location of a file.
-	// TODO(gri) can we come up with a better API instead?
-	var srcDir string
-	if len(check.files) > 0 {
-		// FileName may be "" (typically for tests) in which case
-		// we get "." as the srcDir which is what we would want.
-		srcDir = dir(check.fset.Position(check.files[0].Name.Pos()).Filename)
-	}
-
 	for fileNo, file := range check.files {
 		// The package identifier denotes the current package,
 		// but there is no corresponding package object.
@@ -167,6 +224,11 @@
 		fileScope := NewScope(check.pkg.scope, pos, end, check.filename(fileNo))
 		check.recordScope(file, fileScope)
 
+		// determine file directory, necessary to resolve imports
+		// FileName may be "" (typically for tests) in which case
+		// we get "." as the directory which is what we would want.
+		fileDir := dir(check.fset.Position(file.Name.Pos()).Filename)
+
 		for _, decl := range file.Decls {
 			switch d := decl.(type) {
 			case *ast.BadDecl:
@@ -178,35 +240,15 @@
 					switch s := spec.(type) {
 					case *ast.ImportSpec:
 						// import package
-						var imp *Package
 						path, err := validatedImportPath(s.Path.Value)
 						if err != nil {
 							check.errorf(s.Path.Pos(), "invalid import path (%s)", err)
 							continue
 						}
-						if path == "C" && check.conf.FakeImportC {
-							// TODO(gri) shouldn't create a new one each time
-							imp = NewPackage("C", "C")
-							imp.fake = true
-						} else {
-							// ordinary import
-							if importer := check.conf.Importer; importer == nil {
-								err = fmt.Errorf("Config.Importer not installed")
-							} else if importerFrom, ok := importer.(ImporterFrom); ok {
-								imp, err = importerFrom.ImportFrom(path, srcDir, 0)
-								if imp == nil && err == nil {
-									err = fmt.Errorf("Config.Importer.ImportFrom(%s, %s, 0) returned nil but no error", path, pkg.path)
-								}
-							} else {
-								imp, err = importer.Import(path)
-								if imp == nil && err == nil {
-									err = fmt.Errorf("Config.Importer.Import(%s) returned nil but no error", path)
-								}
-							}
-							if err != nil {
-								check.errorf(s.Path.Pos(), "could not import %s (%s)", path, err)
-								continue
-							}
+
+						imp := check.importPackage(s.Path.Pos(), path, fileDir)
+						if imp == nil {
+							continue
 						}
 
 						// add package to list of explicit imports
@@ -214,9 +256,7 @@
 						// for clients; it is not needed for type-checking)
 						if !pkgImports[imp] {
 							pkgImports[imp] = true
-							if imp != Unsafe {
-								pkg.imports = append(pkg.imports, imp)
-							}
+							pkg.imports = append(pkg.imports, imp)
 						}
 
 						// local name overrides imported package name
@@ -274,13 +314,6 @@
 							check.declare(fileScope, nil, obj, token.NoPos)
 						}
 
-					// Alias-related code. Keep for now.
-					// case *ast.AliasSpec:
-					// 	obj := NewAlias(s.Name.Pos(), pkg, s.Name.Name, nil)
-					// 	obj.typ = nil // unresolved
-					// 	obj.kind = d.Tok
-					// 	check.declarePkgObj(s.Name, obj, &declInfo{file: fileScope, init: s.Orig})
-
 					case *ast.ValueSpec:
 						switch d.Tok {
 						case token.CONST:
@@ -347,7 +380,7 @@
 
 					case *ast.TypeSpec:
 						obj := NewTypeName(s.Name.Pos(), pkg, s.Name.Name, nil)
-						check.declarePkgObj(s.Name, obj, &declInfo{file: fileScope, typ: s.Type})
+						check.declarePkgObj(s.Name, obj, &declInfo{file: fileScope, typ: s.Type, alias: s.Assign.IsValid()})
 
 					default:
 						check.invalidAST(s.Pos(), "unknown ast.Spec node %T", s)
diff --git a/libgo/go/go/types/sizes.go b/libgo/go/go/types/sizes.go
index 3bbe5ae..0821a61 100644
--- a/libgo/go/go/types/sizes.go
+++ b/libgo/go/go/types/sizes.go
@@ -153,8 +153,43 @@
 	return s.WordSize // catch-all
 }
 
+// common architecture word sizes and alignments
+var gcArchSizes = map[string]*StdSizes{
+	"386":      {4, 4},
+	"arm":      {4, 4},
+	"arm64":    {8, 8},
+	"amd64":    {8, 8},
+	"amd64p32": {4, 8},
+	"mips":     {4, 4},
+	"mipsle":   {4, 4},
+	"mips64":   {8, 8},
+	"mips64le": {8, 8},
+	"ppc64":    {8, 8},
+	"ppc64le":  {8, 8},
+	"s390x":    {8, 8},
+	// When adding more architectures here,
+	// update the doc string of SizesFor below.
+}
+
+// SizesFor returns the Sizes used by a compiler for an architecture.
+// The result is nil if a compiler/architecture pair is not known.
+//
+// Supported architectures for compiler "gc":
+// "386", "arm", "arm64", "amd64", "amd64p32", "mips", "mipsle",
+// "mips64", "mips64le", "ppc64", "ppc64le", "s390x".
+func SizesFor(compiler, arch string) Sizes {
+	if compiler != "gc" {
+		return nil
+	}
+	s, ok := gcArchSizes[arch]
+	if !ok {
+		return nil
+	}
+	return s
+}
+
 // stdSizes is used if Config.Sizes == nil.
-var stdSizes = StdSizes{8, 8}
+var stdSizes = SizesFor("gc", "amd64")
 
 func (conf *Config) alignof(T Type) int64 {
 	if s := conf.Sizes; s != nil {
diff --git a/libgo/go/go/types/stdlib_test.go b/libgo/go/go/types/stdlib_test.go
index 8fc51d4..56c48b7 100644
--- a/libgo/go/go/types/stdlib_test.go
+++ b/libgo/go/go/types/stdlib_test.go
@@ -101,12 +101,23 @@
 		// get per-file instructions
 		expectErrors := false
 		filename := filepath.Join(path, f.Name())
-		if cmd := firstComment(filename); cmd != "" {
-			switch cmd {
+		if comment := firstComment(filename); comment != "" {
+			fields := strings.Fields(comment)
+			switch fields[0] {
 			case "skip", "compiledir":
 				continue // ignore this file
 			case "errorcheck":
 				expectErrors = true
+				for _, arg := range fields[1:] {
+					if arg == "-0" || arg == "-+" || arg == "-std" {
+						// Marked explicitly as not expected errors (-0),
+						// or marked as compiling runtime/stdlib, which is only done
+						// to trigger runtime/stdlib-only error output.
+						// In both cases, the code should typecheck.
+						expectErrors = false
+						break
+					}
+				}
 			}
 		}
 
@@ -163,6 +174,9 @@
 		"issue15002.go", // uses Mmap; testTestDir should consult build tags
 		"issue16369.go", // go/types handles this correctly - not an issue
 		"issue18459.go", // go/types doesn't check validity of //go:xxx directives
+		"issue18882.go", // go/types doesn't check validity of //go:xxx directives
+		"issue20232.go", // go/types handles larger constants than gc
+		"issue20529.go", // go/types does not have constraints on stack size
 	)
 }
 
diff --git a/libgo/go/go/types/testdata/builtins.src b/libgo/go/go/types/testdata/builtins.src
index 7fb7b58..ecdba51 100644
--- a/libgo/go/go/types/testdata/builtins.src
+++ b/libgo/go/go/types/testdata/builtins.src
@@ -19,6 +19,7 @@
 	_ = append(nil /* ERROR not a slice */ , s)
 	_ = append(x /* ERROR not a slice */ , s)
 	_ = append(s)
+	_ = append(s, nil...)
 	append /* ERROR not used */ (s)
 
 	_ = append(s, b)
diff --git a/libgo/go/go/types/testdata/cycles.src b/libgo/go/go/types/testdata/cycles.src
index 621d83c..b4bd5d8 100644
--- a/libgo/go/go/types/testdata/cycles.src
+++ b/libgo/go/go/types/testdata/cycles.src
@@ -140,4 +140,13 @@
 type (
 	P3 *T13
 	T13 /* ERROR cycle */ T13
-)
\ No newline at end of file
+)
+
+// test cases for issue 18643
+// (type cycle detection when non-type expressions are involved)
+type (
+	T14 [len(T14 /* ERROR cycle */ {})]int
+	T15 [][len(T15 /* ERROR cycle */ {})]int
+	T16 map[[len(T16 /* ERROR cycle */ {1:2})]int]int
+	T17 map[int][len(T17 /* ERROR cycle */ {1:2})]int
+)
diff --git a/libgo/go/go/types/testdata/decls1.src b/libgo/go/go/types/testdata/decls1.src
index cb162f7..1ef2806 100644
--- a/libgo/go/go/types/testdata/decls1.src
+++ b/libgo/go/go/types/testdata/decls1.src
@@ -78,7 +78,7 @@
 	u2 = iface.([]int)
 	u3 = iface.(a /* ERROR "not a type" */ )
 	u4, ok = iface.(int)
-	u5, ok2, ok3 = iface /* ERROR "assignment count mismatch" */ .(int)
+	u5, ok2, ok3 = iface /* ERROR "cannot initialize" */ .(int)
 )
 
 // Constant expression initializations
diff --git a/libgo/go/go/types/testdata/expr3.src b/libgo/go/go/types/testdata/expr3.src
index ab1a9f6..95d5c09 100644
--- a/libgo/go/go/types/testdata/expr3.src
+++ b/libgo/go/go/types/testdata/expr3.src
@@ -207,7 +207,7 @@
 	_ = time.Time{}
 	_ = time.Time{sec /* ERROR "unknown field" */ : 0}
 	_ = time.Time{
-		0 /* ERROR implicit assignment to unexported field sec in time.Time literal */,
+		0 /* ERROR implicit assignment to unexported field wall in time.Time literal */,
 		0 /* ERROR implicit assignment */ ,
 		nil /* ERROR implicit assignment */ ,
 	}
diff --git a/libgo/go/go/types/testdata/issues.src b/libgo/go/go/types/testdata/issues.src
index 6579aa3..8729555 100644
--- a/libgo/go/go/types/testdata/issues.src
+++ b/libgo/go/go/types/testdata/issues.src
@@ -98,8 +98,8 @@
 // issue11347
 // These should not crash.
 var a1, b1 /* ERROR cycle */ , c1 /* ERROR cycle */ b1 = 0 > 0<<""[""[c1]]>c1
-var a2, b2 /* ERROR cycle */ = 0 /* ERROR mismatch */ /* ERROR mismatch */ > 0<<""[b2]
-var a3, b3 /* ERROR cycle */ = int /* ERROR mismatch */ /* ERROR mismatch */ (1<<""[b3])
+var a2, b2 /* ERROR cycle */ = 0 /* ERROR cannot initialize */ /* ERROR cannot initialize */ > 0<<""[b2]
+var a3, b3 /* ERROR cycle */ = int /* ERROR cannot initialize */ /* ERROR cannot initialize */ (1<<""[b3])
 
 // issue10260
 // Check that error messages explain reason for interface assignment failures.
@@ -186,3 +186,24 @@
 	_ = u
 	_ = v
 }
+
+// Test that we don't get "declared but not used"
+// errors in the context of invalid/C objects.
+func issue20358() {
+	var F C /* ERROR "undeclared" */ .F
+	var A C /* ERROR "undeclared" */ .A
+	var S C /* ERROR "undeclared" */ .S
+	type T C /* ERROR "undeclared" */ .T
+	type P C /* ERROR "undeclared" */ .P
+
+	// these variables must be "used" even though
+	// the LHS expressions/types below in which
+	// context they are used are unknown/invalid
+	var f, a, s1, s2, s3, t, p int
+
+	_ = F(f)
+	_ = A[a]
+	_ = S[s1:s2:s3]
+	_ = T{t}
+	_ = P{f: p}
+}
diff --git a/libgo/go/go/types/testdata/shifts.src b/libgo/go/go/types/testdata/shifts.src
index 099c9ec..dc029fc 100644
--- a/libgo/go/go/types/testdata/shifts.src
+++ b/libgo/go/go/types/testdata/shifts.src
@@ -10,7 +10,7 @@
 		s = 10
 		_ = 0<<0
 		_ = 1<<s
-		_ = 1<<- /* ERROR "invalid shift" */ 1
+		_ = 1<<- /* ERROR "overflows uint" */ 1
 		_ = 1<<1075 /* ERROR "invalid shift" */
 		_ = 2.0<<1
 
@@ -39,12 +39,18 @@
 		_ = 1<<u
 		_ = 1<<"foo" /* ERROR "cannot convert" */
 		_ = i<<0
-		_ = i<<- /* ERROR "must not be negative" */ 1
+		_ = i<<- /* ERROR "overflows uint" */ 1
 		_ = 1 /* ERROR "overflows" */ <<100
 
 		_ uint = 1 << 0
 		_ uint = 1 << u
 		_ float32 = 1 /* ERROR "must be integer" */ << u
+
+		// for issue 14822
+		_ = 1<<( /* ERROR "invalid shift count" */ 1<<63)
+		_ = 1<<( /* ERROR "overflows uint" */ 1<<64)
+		_ = u<<(1<<63) // valid
+		_ = u<<( /* ERROR "overflows uint" */ 1<<64)
 	)
 }
 
@@ -321,11 +327,11 @@
 }
 
 func issue11325() {
-	var _ = 0 >> 1.1 /* ERROR "must be unsigned integer" */ // example from issue 11325
-	_ = 0 >> 1.1 /* ERROR "must be unsigned integer" */
-	_ = 0 << 1.1 /* ERROR "must be unsigned integer" */
+	var _ = 0 >> 1.1 /* ERROR "truncated to uint" */ // example from issue 11325
+	_ = 0 >> 1.1 /* ERROR "truncated to uint" */
+	_ = 0 << 1.1 /* ERROR "truncated to uint" */
 	_ = 0 >> 1.
-	_ = 1 >> 1.1 /* ERROR "must be unsigned integer" */
+	_ = 1 >> 1.1 /* ERROR "truncated to uint" */
 	_ = 1 >> 1.
 	_ = 1. >> 1
 	_ = 1. >> 1.
diff --git a/libgo/go/go/types/testdata/stmt0.src b/libgo/go/go/types/testdata/stmt0.src
index 87f08e4..446997a 100644
--- a/libgo/go/go/types/testdata/stmt0.src
+++ b/libgo/go/go/types/testdata/stmt0.src
@@ -15,19 +15,19 @@
 	f3 := func() (int, int, int) { return 1, 2, 3 }
 
 	a, b, c = 1, 2, 3
-	a, b, c = 1 /* ERROR "assignment count mismatch" */ , 2
-	a, b, c = 1 /* ERROR "assignment count mismatch" */ , 2, 3, 4
+	a, b, c = 1 /* ERROR "cannot assign [1-9]+ values to [1-9]+ variables" */ , 2
+	a, b, c = 1 /* ERROR "cannot assign [1-9]+ values to [1-9]+ variables" */ , 2, 3, 4
 	_, _, _ = a, b, c
 
 	a = f0 /* ERROR "used as value" */ ()
 	a = f1()
-	a = f2 /* ERROR "assignment count mismatch" */ ()
+	a = f2 /* ERROR "cannot assign [1-9]+ values to [1-9]+ variables" */ ()
 	a, b = f2()
-	a, b, c = f2 /* ERROR "assignment count mismatch" */ ()
+	a, b, c = f2 /* ERROR "cannot assign [1-9]+ values to [1-9]+ variables" */ ()
 	a, b, c = f3()
-	a, b = f3 /* ERROR "assignment count mismatch" */ ()
+	a, b = f3 /* ERROR "cannot assign [1-9]+ values to [1-9]+ variables" */ ()
 
-	a, b, c = <- /* ERROR "assignment count mismatch" */ ch
+	a, b, c = <- /* ERROR "cannot assign [1-9]+ values to [1-9]+ variables" */ ch
 
 	return /* ERROR "wrong number of return values" */
 	return /* ERROR "wrong number of return values" */ 1
@@ -43,7 +43,7 @@
 	c = s /* ERROR "cannot use .* in assignment" */
 	s = b /* ERROR "cannot use .* in assignment" */
 
-	v0, v1, v2 := 1 /* ERROR "mismatch" */ , 2, 3, 4
+	v0, v1, v2 := 1 /* ERROR "cannot initialize" */ , 2, 3, 4
 	_, _, _ = v0, v1, v2
 
 	b = true
@@ -108,7 +108,7 @@
 	s, b = m["foo"]
 	_, d = m["bar"]
 	m["foo"] = nil
-	m["foo"] = nil /* ERROR assignment count mismatch */ , false
+	m["foo"] = nil /* ERROR cannot assign [1-9]+ values to [1-9]+ variables */ , false
 	_ = append(m["foo"])
 	_ = append(m["foo"], true)
 
@@ -116,12 +116,12 @@
 	_, b = <-c
 	_, d = <-c
 	<- /* ERROR cannot assign */ c = 0
-	<-c = 0 /* ERROR assignment count mismatch */ , false
+	<-c = 0 /* ERROR cannot assign [1-9]+ values to [1-9]+ variables */ , false
 
 	var x interface{}
 	_, b = x.(int)
 	x /* ERROR cannot assign */ .(int) = 0
-	x.(int) = 0 /* ERROR assignment count mismatch */ , false
+	x.(int) = 0 /* ERROR cannot assign [1-9]+ values to [1-9]+ variables */ , false
 
 	assignments2 /* ERROR used as value */ () = nil
 	int /* ERROR not an expression */ = 0
diff --git a/libgo/go/go/types/testdata/vardecl.src b/libgo/go/go/types/testdata/vardecl.src
index 0082537..35f44e6 100644
--- a/libgo/go/go/types/testdata/vardecl.src
+++ b/libgo/go/go/types/testdata/vardecl.src
@@ -28,39 +28,39 @@
 // Identifier and expression arity must match.
 var _, _ = 1, 2
 var _ = 1, 2 /* ERROR "extra init expr 2" */
-var _, _ = 1 /* ERROR "assignment count mismatch" */
+var _, _ = 1 /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */
 var _, _, _ /* ERROR "missing init expr for _" */ = 1, 2
 
 var _ = g /* ERROR "2-valued g" */ ()
 var _, _ = g()
-var _, _, _ = g /* ERROR "assignment count mismatch" */ ()
+var _, _, _ = g /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */ ()
 
 var _ = m["foo"]
 var _, _ = m["foo"]
-var _, _, _ = m  /* ERROR "assignment count mismatch" */ ["foo"]
+var _, _, _ = m  /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */ ["foo"]
 
 var _, _ int = 1, 2
 var _ int = 1, 2 /* ERROR "extra init expr 2" */
-var _, _ int = 1 /* ERROR "assignment count mismatch" */
+var _, _ int = 1 /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */
 var _, _, _ /* ERROR "missing init expr for _" */ int = 1, 2
 
 var (
 	_, _ = 1, 2
 	_ = 1, 2 /* ERROR "extra init expr 2" */
-	_, _ = 1 /* ERROR "assignment count mismatch" */
+	_, _ = 1 /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */
 	_, _, _ /* ERROR "missing init expr for _" */ = 1, 2
 
 	_ = g /* ERROR "2-valued g" */ ()
 	_, _ = g()
-	_, _, _ = g /* ERROR "assignment count mismatch" */ ()
+	_, _, _ = g /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */ ()
 
 	_ = m["foo"]
 	_, _ = m["foo"]
-	_, _, _ = m /* ERROR "assignment count mismatch" */ ["foo"]
+	_, _, _ = m /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */ ["foo"]
 
 	_, _ int = 1, 2
 	_ int = 1, 2 /* ERROR "extra init expr 2" */
-	_, _ int = 1 /* ERROR "assignment count mismatch" */
+	_, _ int = 1 /* ERROR "cannot initialize [0-9]+ variables with [0-9]+ values" */
 	_, _, _ /* ERROR "missing init expr for _" */ int = 1, 2
 )
 
@@ -155,7 +155,7 @@
 func _() {
 	var a, b, c int
 	var x, y int
-	x, y = a /* ERROR assignment count mismatch */ , b, c
+	x, y = a /* ERROR cannot assign [0-9]+ values to [0-9]+ variables */ , b, c
 	_ = x
 	_ = y
 }
diff --git a/libgo/go/go/types/type.go b/libgo/go/go/types/type.go
index 01adee8..a0a1238 100644
--- a/libgo/go/go/types/type.go
+++ b/libgo/go/go/types/type.go
@@ -394,7 +394,7 @@
 	return typ
 }
 
-// TypeName returns the type name for the named type t.
+// Obj returns the type name for the named type t.
 func (t *Named) Obj() *TypeName { return t.obj }
 
 // NumMethods returns the number of explicit methods whose receiver is named type t.
diff --git a/libgo/go/go/types/typestring.go b/libgo/go/go/types/typestring.go
index 47378e7..0f8a7ad 100644
--- a/libgo/go/go/types/typestring.go
+++ b/libgo/go/go/types/typestring.go
@@ -56,6 +56,7 @@
 // This flag is exported in the x/tools/go/types package. We don't
 // need it at the moment in the std repo and so we don't export it
 // anymore. We should eventually try to remove it altogether.
+// TODO(gri) remove this
 var gcCompatibilityMode bool
 
 // TypeString returns the string representation of typ.
diff --git a/libgo/go/go/types/typestring_test.go b/libgo/go/go/types/typestring_test.go
index 52aa6b6..7f7c106 100644
--- a/libgo/go/go/types/typestring_test.go
+++ b/libgo/go/go/types/typestring_test.go
@@ -17,8 +17,7 @@
 
 const filename = "<src>"
 
-func makePkg(t *testing.T, src string) (*Package, error) {
-	t.Skip("skipping for gccgo--no importer")
+func makePkg(src string) (*Package, error) {
 	fset := token.NewFileSet()
 	file, err := parser.ParseFile(fset, filename, src, parser.DeclarationErrors)
 	if err != nil {
@@ -127,7 +126,7 @@
 
 	for _, test := range tests {
 		src := `package p; import "io"; type _ io.Writer; type T ` + test.src
-		pkg, err := makePkg(t, src)
+		pkg, err := makePkg(src)
 		if err != nil {
 			t.Errorf("%s: %s", src, err)
 			continue
diff --git a/libgo/go/go/types/typexpr.go b/libgo/go/go/types/typexpr.go
index ecc0a7d..5f1587b 100644
--- a/libgo/go/go/types/typexpr.go
+++ b/libgo/go/go/types/typexpr.go
@@ -45,17 +45,6 @@
 		delete(check.unusedDotImports[scope], pkg)
 	}
 
-	// Alias-related code. Keep for now.
-	// An alias stands for the original object; use that one instead.
-	// TODO(gri) We should be able to factor out the Typ[Invalid] test.
-	// if alias, _ := obj.(*Alias); alias != nil {
-	// 	obj = original(obj)
-	// 	if obj == nil || typ == Typ[Invalid] {
-	// 		return
-	// 	}
-	// 	assert(typ == obj.Type())
-	// }
-
 	switch obj := obj.(type) {
 	case *PkgName:
 		check.errorf(e.Pos(), "use of package %s not in selector", obj.name)
@@ -634,7 +623,7 @@
 	// current field typ and tag
 	var typ Type
 	var tag string
-	add := func(field *ast.Field, ident *ast.Ident, anonymous bool, pos token.Pos) {
+	add := func(ident *ast.Ident, anonymous bool, pos token.Pos) {
 		if tag != "" && tags == nil {
 			tags = make([]string, len(fields))
 		}
@@ -657,51 +646,45 @@
 		if len(f.Names) > 0 {
 			// named fields
 			for _, name := range f.Names {
-				add(f, name, false, name.Pos())
+				add(name, false, name.Pos())
 			}
 		} else {
 			// anonymous field
-			name := anonymousFieldIdent(f.Type)
+			// spec: "An embedded type must be specified as a type name T or as a pointer
+			// to a non-interface type name *T, and T itself may not be a pointer type."
 			pos := f.Type.Pos()
+			name := anonymousFieldIdent(f.Type)
+			if name == nil {
+				check.invalidAST(pos, "anonymous field type %s has no name", f.Type)
+				continue
+			}
 			t, isPtr := deref(typ)
-			switch t := t.(type) {
+			// Because we have a name, typ must be of the form T or *T, where T is the name
+			// of a (named or alias) type, and t (= deref(typ)) must be the type of T.
+			switch t := t.Underlying().(type) {
 			case *Basic:
 				if t == Typ[Invalid] {
 					// error was reported before
 					continue
 				}
+
 				// unsafe.Pointer is treated like a regular pointer
 				if t.kind == UnsafePointer {
 					check.errorf(pos, "anonymous field type cannot be unsafe.Pointer")
 					continue
 				}
-				add(f, name, true, pos)
 
-			case *Named:
-				// spec: "An embedded type must be specified as a type name
-				// T or as a pointer to a non-interface type name *T, and T
-				// itself may not be a pointer type."
-				switch u := t.underlying.(type) {
-				case *Basic:
-					// unsafe.Pointer is treated like a regular pointer
-					if u.kind == UnsafePointer {
-						check.errorf(pos, "anonymous field type cannot be unsafe.Pointer")
-						continue
-					}
-				case *Pointer:
-					check.errorf(pos, "anonymous field type cannot be a pointer")
+			case *Pointer:
+				check.errorf(pos, "anonymous field type cannot be a pointer")
+				continue
+
+			case *Interface:
+				if isPtr {
+					check.errorf(pos, "anonymous field type cannot be a pointer to an interface")
 					continue
-				case *Interface:
-					if isPtr {
-						check.errorf(pos, "anonymous field type cannot be a pointer to an interface")
-						continue
-					}
 				}
-				add(f, name, true, pos)
-
-			default:
-				check.invalidAST(pos, "anonymous field type %s must be named", typ)
 			}
+			add(name, true, pos)
 		}
 	}
 
@@ -714,7 +697,10 @@
 	case *ast.Ident:
 		return e
 	case *ast.StarExpr:
-		return anonymousFieldIdent(e.X)
+		// *T is valid, but **T is not
+		if _, ok := e.X.(*ast.StarExpr); !ok {
+			return anonymousFieldIdent(e.X)
+		}
 	case *ast.SelectorExpr:
 		return e.Sel
 	}
diff --git a/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305.go b/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305.go
index eb6739a..3f0dcb9 100644
--- a/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305.go
+++ b/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305.go
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // Package chacha20poly1305 implements the ChaCha20-Poly1305 AEAD as specified in RFC 7539.
-package chacha20poly1305
+package chacha20poly1305 // import "golang.org/x/crypto/chacha20poly1305"
 
 import (
 	"crypto/cipher"
diff --git a/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go b/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
index 4755033..1e523b9 100644
--- a/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
+++ b/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
@@ -14,13 +14,60 @@
 //go:noescape
 func chacha20Poly1305Seal(dst []byte, key []uint32, src, ad []byte)
 
-//go:noescape
-func haveSSSE3() bool
+// cpuid is implemented in chacha20poly1305_amd64.s.
+func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
 
-var canUseASM bool
+// xgetbv with ecx = 0 is implemented in chacha20poly1305_amd64.s.
+func xgetbv() (eax, edx uint32)
+
+var (
+	useASM  bool
+	useAVX2 bool
+)
 
 func init() {
-	canUseASM = haveSSSE3()
+	detectCpuFeatures()
+}
+
+// detectCpuFeatures is used to detect if cpu instructions
+// used by the functions implemented in assembler in
+// chacha20poly1305_amd64.s are supported.
+func detectCpuFeatures() {
+	maxId, _, _, _ := cpuid(0, 0)
+	if maxId < 1 {
+		return
+	}
+
+	_, _, ecx1, _ := cpuid(1, 0)
+
+	haveSSSE3 := isSet(9, ecx1)
+	useASM = haveSSSE3
+
+	haveOSXSAVE := isSet(27, ecx1)
+
+	osSupportsAVX := false
+	// For XGETBV, OSXSAVE bit is required and sufficient.
+	if haveOSXSAVE {
+		eax, _ := xgetbv()
+		// Check if XMM and YMM registers have OS support.
+		osSupportsAVX = isSet(1, eax) && isSet(2, eax)
+	}
+	haveAVX := isSet(28, ecx1) && osSupportsAVX
+
+	if maxId < 7 {
+		return
+	}
+
+	_, ebx7, _, _ := cpuid(7, 0)
+	haveAVX2 := isSet(5, ebx7) && haveAVX
+	haveBMI2 := isSet(8, ebx7)
+
+	useAVX2 = haveAVX2 && haveBMI2
+}
+
+// isSet checks if bit at bitpos is set in value.
+func isSet(bitpos uint, value uint32) bool {
+	return value&(1<<bitpos) != 0
 }
 
 // setupState writes a ChaCha20 input matrix to state. See
@@ -47,7 +94,7 @@
 }
 
 func (c *chacha20poly1305) seal(dst, nonce, plaintext, additionalData []byte) []byte {
-	if !canUseASM {
+	if !useASM {
 		return c.sealGeneric(dst, nonce, plaintext, additionalData)
 	}
 
@@ -60,7 +107,7 @@
 }
 
 func (c *chacha20poly1305) open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
-	if !canUseASM {
+	if !useASM {
 		return c.openGeneric(dst, nonce, ciphertext, additionalData)
 	}
 
diff --git a/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_test_vectors.go b/libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_vectors_test.go
similarity index 100%
rename from libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_test_vectors.go
rename to libgo/go/golang_org/x/crypto/chacha20poly1305/chacha20poly1305_vectors_test.go
diff --git a/libgo/go/golang_org/x/crypto/chacha20poly1305/internal/chacha20/chacha_test.go b/libgo/go/golang_org/x/crypto/chacha20poly1305/internal/chacha20/chacha_test.go
index ca9663f..b80d34c 100644
--- a/libgo/go/golang_org/x/crypto/chacha20poly1305/internal/chacha20/chacha_test.go
+++ b/libgo/go/golang_org/x/crypto/chacha20poly1305/internal/chacha20/chacha_test.go
@@ -1,3 +1,7 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package chacha20
 
 import (
diff --git a/libgo/go/golang_org/x/crypto/curve25519/curve25519.go b/libgo/go/golang_org/x/crypto/curve25519/curve25519.go
index 6918c47..2d14c2a 100644
--- a/libgo/go/golang_org/x/crypto/curve25519/curve25519.go
+++ b/libgo/go/golang_org/x/crypto/curve25519/curve25519.go
@@ -8,6 +8,10 @@
 
 package curve25519
 
+import (
+	"encoding/binary"
+)
+
 // This code is a port of the public domain, "ref10" implementation of
 // curve25519 from SUPERCOP 20130419 by D. J. Bernstein.
 
@@ -50,17 +54,11 @@
 //
 // Preconditions: b in {0,1}.
 func feCSwap(f, g *fieldElement, b int32) {
-	var x fieldElement
 	b = -b
-	for i := range x {
-		x[i] = b & (f[i] ^ g[i])
-	}
-
 	for i := range f {
-		f[i] ^= x[i]
-	}
-	for i := range g {
-		g[i] ^= x[i]
+		t := b & (f[i] ^ g[i])
+		f[i] ^= t
+		g[i] ^= t
 	}
 }
 
@@ -75,12 +73,7 @@
 
 // load4 reads a 32-bit, little-endian value from in.
 func load4(in []byte) int64 {
-	var r int64
-	r = int64(in[0])
-	r |= int64(in[1]) << 8
-	r |= int64(in[2]) << 16
-	r |= int64(in[3]) << 24
-	return r
+	return int64(binary.LittleEndian.Uint32(in))
 }
 
 func feFromBytes(dst *fieldElement, src *[32]byte) {
diff --git a/libgo/go/golang_org/x/crypto/curve25519/curve25519_test.go b/libgo/go/golang_org/x/crypto/curve25519/curve25519_test.go
index 14b0ee8..051a830 100644
--- a/libgo/go/golang_org/x/crypto/curve25519/curve25519_test.go
+++ b/libgo/go/golang_org/x/crypto/curve25519/curve25519_test.go
@@ -27,3 +27,13 @@
 		t.Errorf("incorrect result: got %s, want %s", result, expectedHex)
 	}
 }
+
+func BenchmarkScalarBaseMult(b *testing.B) {
+	var in, out [32]byte
+	in[0] = 1
+
+	b.SetBytes(32)
+	for i := 0; i < b.N; i++ {
+		ScalarBaseMult(&out, &in)
+	}
+}
diff --git a/libgo/go/golang_org/x/crypto/poly1305/poly1305_test.go b/libgo/go/golang_org/x/crypto/poly1305/poly1305_test.go
index 91b8e2b..017027f 100644
--- a/libgo/go/golang_org/x/crypto/poly1305/poly1305_test.go
+++ b/libgo/go/golang_org/x/crypto/poly1305/poly1305_test.go
@@ -6,10 +6,14 @@
 
 import (
 	"bytes"
+	"encoding/hex"
+	"flag"
 	"testing"
 	"unsafe"
 )
 
+var stressFlag = flag.Bool("stress", false, "run slow stress tests")
+
 var testData = []struct {
 	in, k, correct []byte
 }{
@@ -39,6 +43,36 @@
 		[]byte{0x3b, 0x3a, 0x29, 0xe9, 0x3b, 0x21, 0x3a, 0x5c, 0x5c, 0x3b, 0x3b, 0x05, 0x3a, 0x3a, 0x8c, 0x0d},
 		[]byte{0x6d, 0xc1, 0x8b, 0x8c, 0x34, 0x4c, 0xd7, 0x99, 0x27, 0x11, 0x8b, 0xbe, 0x84, 0xb7, 0xf3, 0x14},
 	},
+	{
+		// This test generates a result of (2^130-1) % (2^130-5).
+		[]byte{
+			0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		},
+		[]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+		[]byte{4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	},
+	{
+		// This test generates a result of (2^130-6) % (2^130-5).
+		[]byte{
+			0xfa, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		},
+		[]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+		[]byte{0xfa, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
+	},
+	{
+		// This test generates a result of (2^130-5) % (2^130-5).
+		[]byte{
+			0xfb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		},
+		[]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+		[]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	},
 }
 
 func testSum(t *testing.T, unaligned bool) {
@@ -58,6 +92,39 @@
 	}
 }
 
+func TestBurnin(t *testing.T) {
+	// This test can be used to sanity-check significant changes. It can
+	// take about many minutes to run, even on fast machines. It's disabled
+	// by default.
+	if !*stressFlag {
+		t.Skip("skipping without -stress")
+	}
+
+	var key [32]byte
+	var input [25]byte
+	var output [16]byte
+
+	for i := range key {
+		key[i] = 1
+	}
+	for i := range input {
+		input[i] = 2
+	}
+
+	for i := uint64(0); i < 1e10; i++ {
+		Sum(&output, input[:], &key)
+		copy(key[0:], output[:])
+		copy(key[16:], output[:])
+		copy(input[:], output[:])
+		copy(input[16:], output[:])
+	}
+
+	const expected = "5e3b866aea0b636d240c83c428f84bfa"
+	if got := hex.EncodeToString(output[:]); got != expected {
+		t.Errorf("expected %s, got %s", expected, got)
+	}
+}
+
 func TestSum(t *testing.T)          { testSum(t, false) }
 func TestSumUnaligned(t *testing.T) { testSum(t, true) }
 
diff --git a/libgo/go/golang_org/x/crypto/poly1305/sum_ref.go b/libgo/go/golang_org/x/crypto/poly1305/sum_ref.go
index dbe50e7..b2805a5 100644
--- a/libgo/go/golang_org/x/crypto/poly1305/sum_ref.go
+++ b/libgo/go/golang_org/x/crypto/poly1305/sum_ref.go
@@ -6,1526 +6,136 @@
 
 package poly1305
 
-// Based on original, public domain implementation from NaCl by D. J.
-// Bernstein.
+import "encoding/binary"
 
-import "math"
-
-const (
-	alpham80 = 0.00000000558793544769287109375
-	alpham48 = 24.0
-	alpham16 = 103079215104.0
-	alpha0   = 6755399441055744.0
-	alpha18  = 1770887431076116955136.0
-	alpha32  = 29014219670751100192948224.0
-	alpha50  = 7605903601369376408980219232256.0
-	alpha64  = 124615124604835863084731911901282304.0
-	alpha82  = 32667107224410092492483962313449748299776.0
-	alpha96  = 535217884764734955396857238543560676143529984.0
-	alpha112 = 35076039295941670036888435985190792471742381031424.0
-	alpha130 = 9194973245195333150150082162901855101712434733101613056.0
-	scale    = 0.0000000000000000000000000000000000000036734198463196484624023016788195177431833298649127735047148490821200539357960224151611328125
-	offset0  = 6755408030990331.0
-	offset1  = 29014256564239239022116864.0
-	offset2  = 124615283061160854719918951570079744.0
-	offset3  = 535219245894202480694386063513315216128475136.0
-)
-
-// Sum generates an authenticator for m using a one-time key and puts the
+// Sum generates an authenticator for msg using a one-time key and puts the
 // 16-byte result into out. Authenticating two different messages with the same
 // key allows an attacker to forge messages at will.
-func Sum(out *[16]byte, m []byte, key *[32]byte) {
-	r := key
-	s := key[16:]
+func Sum(out *[TagSize]byte, msg []byte, key *[32]byte) {
 	var (
-		y7        float64
-		y6        float64
-		y1        float64
-		y0        float64
-		y5        float64
-		y4        float64
-		x7        float64
-		x6        float64
-		x1        float64
-		x0        float64
-		y3        float64
-		y2        float64
-		x5        float64
-		r3lowx0   float64
-		x4        float64
-		r0lowx6   float64
-		x3        float64
-		r3highx0  float64
-		x2        float64
-		r0highx6  float64
-		r0lowx0   float64
-		sr1lowx6  float64
-		r0highx0  float64
-		sr1highx6 float64
-		sr3low    float64
-		r1lowx0   float64
-		sr2lowx6  float64
-		r1highx0  float64
-		sr2highx6 float64
-		r2lowx0   float64
-		sr3lowx6  float64
-		r2highx0  float64
-		sr3highx6 float64
-		r1highx4  float64
-		r1lowx4   float64
-		r0highx4  float64
-		r0lowx4   float64
-		sr3highx4 float64
-		sr3lowx4  float64
-		sr2highx4 float64
-		sr2lowx4  float64
-		r0lowx2   float64
-		r0highx2  float64
-		r1lowx2   float64
-		r1highx2  float64
-		r2lowx2   float64
-		r2highx2  float64
-		sr3lowx2  float64
-		sr3highx2 float64
-		z0        float64
-		z1        float64
-		z2        float64
-		z3        float64
-		m0        int64
-		m1        int64
-		m2        int64
-		m3        int64
-		m00       uint32
-		m01       uint32
-		m02       uint32
-		m03       uint32
-		m10       uint32
-		m11       uint32
-		m12       uint32
-		m13       uint32
-		m20       uint32
-		m21       uint32
-		m22       uint32
-		m23       uint32
-		m30       uint32
-		m31       uint32
-		m32       uint32
-		m33       uint64
-		lbelow2   int32
-		lbelow3   int32
-		lbelow4   int32
-		lbelow5   int32
-		lbelow6   int32
-		lbelow7   int32
-		lbelow8   int32
-		lbelow9   int32
-		lbelow10  int32
-		lbelow11  int32
-		lbelow12  int32
-		lbelow13  int32
-		lbelow14  int32
-		lbelow15  int32
-		s00       uint32
-		s01       uint32
-		s02       uint32
-		s03       uint32
-		s10       uint32
-		s11       uint32
-		s12       uint32
-		s13       uint32
-		s20       uint32
-		s21       uint32
-		s22       uint32
-		s23       uint32
-		s30       uint32
-		s31       uint32
-		s32       uint32
-		s33       uint32
-		bits32    uint64
-		f         uint64
-		f0        uint64
-		f1        uint64
-		f2        uint64
-		f3        uint64
-		f4        uint64
-		g         uint64
-		g0        uint64
-		g1        uint64
-		g2        uint64
-		g3        uint64
-		g4        uint64
+		h0, h1, h2, h3, h4 uint32 // the hash accumulators
+		r0, r1, r2, r3, r4 uint64 // the r part of the key
 	)
 
-	var p int32
+	r0 = uint64(binary.LittleEndian.Uint32(key[0:]) & 0x3ffffff)
+	r1 = uint64((binary.LittleEndian.Uint32(key[3:]) >> 2) & 0x3ffff03)
+	r2 = uint64((binary.LittleEndian.Uint32(key[6:]) >> 4) & 0x3ffc0ff)
+	r3 = uint64((binary.LittleEndian.Uint32(key[9:]) >> 6) & 0x3f03fff)
+	r4 = uint64((binary.LittleEndian.Uint32(key[12:]) >> 8) & 0x00fffff)
 
-	l := int32(len(m))
+	R1, R2, R3, R4 := r1*5, r2*5, r3*5, r4*5
 
-	r00 := uint32(r[0])
+	for len(msg) >= TagSize {
+		// h += msg
+		h0 += binary.LittleEndian.Uint32(msg[0:]) & 0x3ffffff
+		h1 += (binary.LittleEndian.Uint32(msg[3:]) >> 2) & 0x3ffffff
+		h2 += (binary.LittleEndian.Uint32(msg[6:]) >> 4) & 0x3ffffff
+		h3 += (binary.LittleEndian.Uint32(msg[9:]) >> 6) & 0x3ffffff
+		h4 += (binary.LittleEndian.Uint32(msg[12:]) >> 8) | (1 << 24)
 
-	r01 := uint32(r[1])
+		// h *= r
+		d0 := (uint64(h0) * r0) + (uint64(h1) * R4) + (uint64(h2) * R3) + (uint64(h3) * R2) + (uint64(h4) * R1)
+		d1 := (d0 >> 26) + (uint64(h0) * r1) + (uint64(h1) * r0) + (uint64(h2) * R4) + (uint64(h3) * R3) + (uint64(h4) * R2)
+		d2 := (d1 >> 26) + (uint64(h0) * r2) + (uint64(h1) * r1) + (uint64(h2) * r0) + (uint64(h3) * R4) + (uint64(h4) * R3)
+		d3 := (d2 >> 26) + (uint64(h0) * r3) + (uint64(h1) * r2) + (uint64(h2) * r1) + (uint64(h3) * r0) + (uint64(h4) * R4)
+		d4 := (d3 >> 26) + (uint64(h0) * r4) + (uint64(h1) * r3) + (uint64(h2) * r2) + (uint64(h3) * r1) + (uint64(h4) * r0)
 
-	r02 := uint32(r[2])
-	r0 := int64(2151)
+		// h %= p
+		h0 = uint32(d0) & 0x3ffffff
+		h1 = uint32(d1) & 0x3ffffff
+		h2 = uint32(d2) & 0x3ffffff
+		h3 = uint32(d3) & 0x3ffffff
+		h4 = uint32(d4) & 0x3ffffff
 
-	r03 := uint32(r[3])
-	r03 &= 15
-	r0 <<= 51
+		h0 += uint32(d4>>26) * 5
+		h1 += h0 >> 26
+		h0 = h0 & 0x3ffffff
 
-	r10 := uint32(r[4])
-	r10 &= 252
-	r01 <<= 8
-	r0 += int64(r00)
-
-	r11 := uint32(r[5])
-	r02 <<= 16
-	r0 += int64(r01)
-
-	r12 := uint32(r[6])
-	r03 <<= 24
-	r0 += int64(r02)
-
-	r13 := uint32(r[7])
-	r13 &= 15
-	r1 := int64(2215)
-	r0 += int64(r03)
-
-	d0 := r0
-	r1 <<= 51
-	r2 := int64(2279)
-
-	r20 := uint32(r[8])
-	r20 &= 252
-	r11 <<= 8
-	r1 += int64(r10)
-
-	r21 := uint32(r[9])
-	r12 <<= 16
-	r1 += int64(r11)
-
-	r22 := uint32(r[10])
-	r13 <<= 24
-	r1 += int64(r12)
-
-	r23 := uint32(r[11])
-	r23 &= 15
-	r2 <<= 51
-	r1 += int64(r13)
-
-	d1 := r1
-	r21 <<= 8
-	r2 += int64(r20)
-
-	r30 := uint32(r[12])
-	r30 &= 252
-	r22 <<= 16
-	r2 += int64(r21)
-
-	r31 := uint32(r[13])
-	r23 <<= 24
-	r2 += int64(r22)
-
-	r32 := uint32(r[14])
-	r2 += int64(r23)
-	r3 := int64(2343)
-
-	d2 := r2
-	r3 <<= 51
-
-	r33 := uint32(r[15])
-	r33 &= 15
-	r31 <<= 8
-	r3 += int64(r30)
-
-	r32 <<= 16
-	r3 += int64(r31)
-
-	r33 <<= 24
-	r3 += int64(r32)
-
-	r3 += int64(r33)
-	h0 := alpha32 - alpha32
-
-	d3 := r3
-	h1 := alpha32 - alpha32
-
-	h2 := alpha32 - alpha32
-
-	h3 := alpha32 - alpha32
-
-	h4 := alpha32 - alpha32
-
-	r0low := math.Float64frombits(uint64(d0))
-	h5 := alpha32 - alpha32
-
-	r1low := math.Float64frombits(uint64(d1))
-	h6 := alpha32 - alpha32
-
-	r2low := math.Float64frombits(uint64(d2))
-	h7 := alpha32 - alpha32
-
-	r0low -= alpha0
-
-	r1low -= alpha32
-
-	r2low -= alpha64
-
-	r0high := r0low + alpha18
-
-	r3low := math.Float64frombits(uint64(d3))
-
-	r1high := r1low + alpha50
-	sr1low := scale * r1low
-
-	r2high := r2low + alpha82
-	sr2low := scale * r2low
-
-	r0high -= alpha18
-	r0high_stack := r0high
-
-	r3low -= alpha96
-
-	r1high -= alpha50
-	r1high_stack := r1high
-
-	sr1high := sr1low + alpham80
-
-	r0low -= r0high
-
-	r2high -= alpha82
-	sr3low = scale * r3low
-
-	sr2high := sr2low + alpham48
-
-	r1low -= r1high
-	r1low_stack := r1low
-
-	sr1high -= alpham80
-	sr1high_stack := sr1high
-
-	r2low -= r2high
-	r2low_stack := r2low
-
-	sr2high -= alpham48
-	sr2high_stack := sr2high
-
-	r3high := r3low + alpha112
-	r0low_stack := r0low
-
-	sr1low -= sr1high
-	sr1low_stack := sr1low
-
-	sr3high := sr3low + alpham16
-	r2high_stack := r2high
-
-	sr2low -= sr2high
-	sr2low_stack := sr2low
-
-	r3high -= alpha112
-	r3high_stack := r3high
-
-	sr3high -= alpham16
-	sr3high_stack := sr3high
-
-	r3low -= r3high
-	r3low_stack := r3low
-
-	sr3low -= sr3high
-	sr3low_stack := sr3low
-
-	if l < 16 {
-		goto addatmost15bytes
+		msg = msg[TagSize:]
 	}
 
-	m00 = uint32(m[p+0])
-	m0 = 2151
+	if len(msg) > 0 {
+		var block [TagSize]byte
+		off := copy(block[:], msg)
+		block[off] = 0x01
 
-	m0 <<= 51
-	m1 = 2215
-	m01 = uint32(m[p+1])
+		// h += msg
+		h0 += binary.LittleEndian.Uint32(block[0:]) & 0x3ffffff
+		h1 += (binary.LittleEndian.Uint32(block[3:]) >> 2) & 0x3ffffff
+		h2 += (binary.LittleEndian.Uint32(block[6:]) >> 4) & 0x3ffffff
+		h3 += (binary.LittleEndian.Uint32(block[9:]) >> 6) & 0x3ffffff
+		h4 += (binary.LittleEndian.Uint32(block[12:]) >> 8)
 
-	m1 <<= 51
-	m2 = 2279
-	m02 = uint32(m[p+2])
+		// h *= r
+		d0 := (uint64(h0) * r0) + (uint64(h1) * R4) + (uint64(h2) * R3) + (uint64(h3) * R2) + (uint64(h4) * R1)
+		d1 := (d0 >> 26) + (uint64(h0) * r1) + (uint64(h1) * r0) + (uint64(h2) * R4) + (uint64(h3) * R3) + (uint64(h4) * R2)
+		d2 := (d1 >> 26) + (uint64(h0) * r2) + (uint64(h1) * r1) + (uint64(h2) * r0) + (uint64(h3) * R4) + (uint64(h4) * R3)
+		d3 := (d2 >> 26) + (uint64(h0) * r3) + (uint64(h1) * r2) + (uint64(h2) * r1) + (uint64(h3) * r0) + (uint64(h4) * R4)
+		d4 := (d3 >> 26) + (uint64(h0) * r4) + (uint64(h1) * r3) + (uint64(h2) * r2) + (uint64(h3) * r1) + (uint64(h4) * r0)
 
-	m2 <<= 51
-	m3 = 2343
-	m03 = uint32(m[p+3])
+		// h %= p
+		h0 = uint32(d0) & 0x3ffffff
+		h1 = uint32(d1) & 0x3ffffff
+		h2 = uint32(d2) & 0x3ffffff
+		h3 = uint32(d3) & 0x3ffffff
+		h4 = uint32(d4) & 0x3ffffff
 
-	m10 = uint32(m[p+4])
-	m01 <<= 8
-	m0 += int64(m00)
-
-	m11 = uint32(m[p+5])
-	m02 <<= 16
-	m0 += int64(m01)
-
-	m12 = uint32(m[p+6])
-	m03 <<= 24
-	m0 += int64(m02)
-
-	m13 = uint32(m[p+7])
-	m3 <<= 51
-	m0 += int64(m03)
-
-	m20 = uint32(m[p+8])
-	m11 <<= 8
-	m1 += int64(m10)
-
-	m21 = uint32(m[p+9])
-	m12 <<= 16
-	m1 += int64(m11)
-
-	m22 = uint32(m[p+10])
-	m13 <<= 24
-	m1 += int64(m12)
-
-	m23 = uint32(m[p+11])
-	m1 += int64(m13)
-
-	m30 = uint32(m[p+12])
-	m21 <<= 8
-	m2 += int64(m20)
-
-	m31 = uint32(m[p+13])
-	m22 <<= 16
-	m2 += int64(m21)
-
-	m32 = uint32(m[p+14])
-	m23 <<= 24
-	m2 += int64(m22)
-
-	m33 = uint64(m[p+15])
-	m2 += int64(m23)
-
-	d0 = m0
-	m31 <<= 8
-	m3 += int64(m30)
-
-	d1 = m1
-	m32 <<= 16
-	m3 += int64(m31)
-
-	d2 = m2
-	m33 += 256
-
-	m33 <<= 24
-	m3 += int64(m32)
-
-	m3 += int64(m33)
-	d3 = m3
-
-	p += 16
-	l -= 16
-
-	z0 = math.Float64frombits(uint64(d0))
-
-	z1 = math.Float64frombits(uint64(d1))
-
-	z2 = math.Float64frombits(uint64(d2))
-
-	z3 = math.Float64frombits(uint64(d3))
-
-	z0 -= alpha0
-
-	z1 -= alpha32
-
-	z2 -= alpha64
-
-	z3 -= alpha96
-
-	h0 += z0
-
-	h1 += z1
-
-	h3 += z2
-
-	h5 += z3
-
-	if l < 16 {
-		goto multiplyaddatmost15bytes
+		h0 += uint32(d4>>26) * 5
+		h1 += h0 >> 26
+		h0 = h0 & 0x3ffffff
 	}
 
-multiplyaddatleast16bytes:
+	// h %= p reduction
+	h2 += h1 >> 26
+	h1 &= 0x3ffffff
+	h3 += h2 >> 26
+	h2 &= 0x3ffffff
+	h4 += h3 >> 26
+	h3 &= 0x3ffffff
+	h0 += 5 * (h4 >> 26)
+	h4 &= 0x3ffffff
+	h1 += h0 >> 26
+	h0 &= 0x3ffffff
 
-	m2 = 2279
-	m20 = uint32(m[p+8])
-	y7 = h7 + alpha130
+	// h - p
+	t0 := h0 + 5
+	t1 := h1 + (t0 >> 26)
+	t2 := h2 + (t1 >> 26)
+	t3 := h3 + (t2 >> 26)
+	t4 := h4 + (t3 >> 26) - (1 << 26)
+	t0 &= 0x3ffffff
+	t1 &= 0x3ffffff
+	t2 &= 0x3ffffff
+	t3 &= 0x3ffffff
 
-	m2 <<= 51
-	m3 = 2343
-	m21 = uint32(m[p+9])
-	y6 = h6 + alpha130
+	// select h if h < p else h - p
+	t_mask := (t4 >> 31) - 1
+	h_mask := ^t_mask
+	h0 = (h0 & h_mask) | (t0 & t_mask)
+	h1 = (h1 & h_mask) | (t1 & t_mask)
+	h2 = (h2 & h_mask) | (t2 & t_mask)
+	h3 = (h3 & h_mask) | (t3 & t_mask)
+	h4 = (h4 & h_mask) | (t4 & t_mask)
 
-	m3 <<= 51
-	m0 = 2151
-	m22 = uint32(m[p+10])
-	y1 = h1 + alpha32
+	// h %= 2^128
+	h0 |= h1 << 26
+	h1 = ((h1 >> 6) | (h2 << 20))
+	h2 = ((h2 >> 12) | (h3 << 14))
+	h3 = ((h3 >> 18) | (h4 << 8))
 
-	m0 <<= 51
-	m1 = 2215
-	m23 = uint32(m[p+11])
-	y0 = h0 + alpha32
+	// s: the s part of the key
+	// tag = (h + s) % (2^128)
+	t := uint64(h0) + uint64(binary.LittleEndian.Uint32(key[16:]))
+	h0 = uint32(t)
+	t = uint64(h1) + uint64(binary.LittleEndian.Uint32(key[20:])) + (t >> 32)
+	h1 = uint32(t)
+	t = uint64(h2) + uint64(binary.LittleEndian.Uint32(key[24:])) + (t >> 32)
+	h2 = uint32(t)
+	t = uint64(h3) + uint64(binary.LittleEndian.Uint32(key[28:])) + (t >> 32)
+	h3 = uint32(t)
 
-	m1 <<= 51
-	m30 = uint32(m[p+12])
-	y7 -= alpha130
-
-	m21 <<= 8
-	m2 += int64(m20)
-	m31 = uint32(m[p+13])
-	y6 -= alpha130
-
-	m22 <<= 16
-	m2 += int64(m21)
-	m32 = uint32(m[p+14])
-	y1 -= alpha32
-
-	m23 <<= 24
-	m2 += int64(m22)
-	m33 = uint64(m[p+15])
-	y0 -= alpha32
-
-	m2 += int64(m23)
-	m00 = uint32(m[p+0])
-	y5 = h5 + alpha96
-
-	m31 <<= 8
-	m3 += int64(m30)
-	m01 = uint32(m[p+1])
-	y4 = h4 + alpha96
-
-	m32 <<= 16
-	m02 = uint32(m[p+2])
-	x7 = h7 - y7
-	y7 *= scale
-
-	m33 += 256
-	m03 = uint32(m[p+3])
-	x6 = h6 - y6
-	y6 *= scale
-
-	m33 <<= 24
-	m3 += int64(m31)
-	m10 = uint32(m[p+4])
-	x1 = h1 - y1
-
-	m01 <<= 8
-	m3 += int64(m32)
-	m11 = uint32(m[p+5])
-	x0 = h0 - y0
-
-	m3 += int64(m33)
-	m0 += int64(m00)
-	m12 = uint32(m[p+6])
-	y5 -= alpha96
-
-	m02 <<= 16
-	m0 += int64(m01)
-	m13 = uint32(m[p+7])
-	y4 -= alpha96
-
-	m03 <<= 24
-	m0 += int64(m02)
-	d2 = m2
-	x1 += y7
-
-	m0 += int64(m03)
-	d3 = m3
-	x0 += y6
-
-	m11 <<= 8
-	m1 += int64(m10)
-	d0 = m0
-	x7 += y5
-
-	m12 <<= 16
-	m1 += int64(m11)
-	x6 += y4
-
-	m13 <<= 24
-	m1 += int64(m12)
-	y3 = h3 + alpha64
-
-	m1 += int64(m13)
-	d1 = m1
-	y2 = h2 + alpha64
-
-	x0 += x1
-
-	x6 += x7
-
-	y3 -= alpha64
-	r3low = r3low_stack
-
-	y2 -= alpha64
-	r0low = r0low_stack
-
-	x5 = h5 - y5
-	r3lowx0 = r3low * x0
-	r3high = r3high_stack
-
-	x4 = h4 - y4
-	r0lowx6 = r0low * x6
-	r0high = r0high_stack
-
-	x3 = h3 - y3
-	r3highx0 = r3high * x0
-	sr1low = sr1low_stack
-
-	x2 = h2 - y2
-	r0highx6 = r0high * x6
-	sr1high = sr1high_stack
-
-	x5 += y3
-	r0lowx0 = r0low * x0
-	r1low = r1low_stack
-
-	h6 = r3lowx0 + r0lowx6
-	sr1lowx6 = sr1low * x6
-	r1high = r1high_stack
-
-	x4 += y2
-	r0highx0 = r0high * x0
-	sr2low = sr2low_stack
-
-	h7 = r3highx0 + r0highx6
-	sr1highx6 = sr1high * x6
-	sr2high = sr2high_stack
-
-	x3 += y1
-	r1lowx0 = r1low * x0
-	r2low = r2low_stack
-
-	h0 = r0lowx0 + sr1lowx6
-	sr2lowx6 = sr2low * x6
-	r2high = r2high_stack
-
-	x2 += y0
-	r1highx0 = r1high * x0
-	sr3low = sr3low_stack
-
-	h1 = r0highx0 + sr1highx6
-	sr2highx6 = sr2high * x6
-	sr3high = sr3high_stack
-
-	x4 += x5
-	r2lowx0 = r2low * x0
-	z2 = math.Float64frombits(uint64(d2))
-
-	h2 = r1lowx0 + sr2lowx6
-	sr3lowx6 = sr3low * x6
-
-	x2 += x3
-	r2highx0 = r2high * x0
-	z3 = math.Float64frombits(uint64(d3))
-
-	h3 = r1highx0 + sr2highx6
-	sr3highx6 = sr3high * x6
-
-	r1highx4 = r1high * x4
-	z2 -= alpha64
-
-	h4 = r2lowx0 + sr3lowx6
-	r1lowx4 = r1low * x4
-
-	r0highx4 = r0high * x4
-	z3 -= alpha96
-
-	h5 = r2highx0 + sr3highx6
-	r0lowx4 = r0low * x4
-
-	h7 += r1highx4
-	sr3highx4 = sr3high * x4
-
-	h6 += r1lowx4
-	sr3lowx4 = sr3low * x4
-
-	h5 += r0highx4
-	sr2highx4 = sr2high * x4
-
-	h4 += r0lowx4
-	sr2lowx4 = sr2low * x4
-
-	h3 += sr3highx4
-	r0lowx2 = r0low * x2
-
-	h2 += sr3lowx4
-	r0highx2 = r0high * x2
-
-	h1 += sr2highx4
-	r1lowx2 = r1low * x2
-
-	h0 += sr2lowx4
-	r1highx2 = r1high * x2
-
-	h2 += r0lowx2
-	r2lowx2 = r2low * x2
-
-	h3 += r0highx2
-	r2highx2 = r2high * x2
-
-	h4 += r1lowx2
-	sr3lowx2 = sr3low * x2
-
-	h5 += r1highx2
-	sr3highx2 = sr3high * x2
-
-	p += 16
-	l -= 16
-	h6 += r2lowx2
-
-	h7 += r2highx2
-
-	z1 = math.Float64frombits(uint64(d1))
-	h0 += sr3lowx2
-
-	z0 = math.Float64frombits(uint64(d0))
-	h1 += sr3highx2
-
-	z1 -= alpha32
-
-	z0 -= alpha0
-
-	h5 += z3
-
-	h3 += z2
-
-	h1 += z1
-
-	h0 += z0
-
-	if l >= 16 {
-		goto multiplyaddatleast16bytes
-	}
-
-multiplyaddatmost15bytes:
-
-	y7 = h7 + alpha130
-
-	y6 = h6 + alpha130
-
-	y1 = h1 + alpha32
-
-	y0 = h0 + alpha32
-
-	y7 -= alpha130
-
-	y6 -= alpha130
-
-	y1 -= alpha32
-
-	y0 -= alpha32
-
-	y5 = h5 + alpha96
-
-	y4 = h4 + alpha96
-
-	x7 = h7 - y7
-	y7 *= scale
-
-	x6 = h6 - y6
-	y6 *= scale
-
-	x1 = h1 - y1
-
-	x0 = h0 - y0
-
-	y5 -= alpha96
-
-	y4 -= alpha96
-
-	x1 += y7
-
-	x0 += y6
-
-	x7 += y5
-
-	x6 += y4
-
-	y3 = h3 + alpha64
-
-	y2 = h2 + alpha64
-
-	x0 += x1
-
-	x6 += x7
-
-	y3 -= alpha64
-	r3low = r3low_stack
-
-	y2 -= alpha64
-	r0low = r0low_stack
-
-	x5 = h5 - y5
-	r3lowx0 = r3low * x0
-	r3high = r3high_stack
-
-	x4 = h4 - y4
-	r0lowx6 = r0low * x6
-	r0high = r0high_stack
-
-	x3 = h3 - y3
-	r3highx0 = r3high * x0
-	sr1low = sr1low_stack
-
-	x2 = h2 - y2
-	r0highx6 = r0high * x6
-	sr1high = sr1high_stack
-
-	x5 += y3
-	r0lowx0 = r0low * x0
-	r1low = r1low_stack
-
-	h6 = r3lowx0 + r0lowx6
-	sr1lowx6 = sr1low * x6
-	r1high = r1high_stack
-
-	x4 += y2
-	r0highx0 = r0high * x0
-	sr2low = sr2low_stack
-
-	h7 = r3highx0 + r0highx6
-	sr1highx6 = sr1high * x6
-	sr2high = sr2high_stack
-
-	x3 += y1
-	r1lowx0 = r1low * x0
-	r2low = r2low_stack
-
-	h0 = r0lowx0 + sr1lowx6
-	sr2lowx6 = sr2low * x6
-	r2high = r2high_stack
-
-	x2 += y0
-	r1highx0 = r1high * x0
-	sr3low = sr3low_stack
-
-	h1 = r0highx0 + sr1highx6
-	sr2highx6 = sr2high * x6
-	sr3high = sr3high_stack
-
-	x4 += x5
-	r2lowx0 = r2low * x0
-
-	h2 = r1lowx0 + sr2lowx6
-	sr3lowx6 = sr3low * x6
-
-	x2 += x3
-	r2highx0 = r2high * x0
-
-	h3 = r1highx0 + sr2highx6
-	sr3highx6 = sr3high * x6
-
-	r1highx4 = r1high * x4
-
-	h4 = r2lowx0 + sr3lowx6
-	r1lowx4 = r1low * x4
-
-	r0highx4 = r0high * x4
-
-	h5 = r2highx0 + sr3highx6
-	r0lowx4 = r0low * x4
-
-	h7 += r1highx4
-	sr3highx4 = sr3high * x4
-
-	h6 += r1lowx4
-	sr3lowx4 = sr3low * x4
-
-	h5 += r0highx4
-	sr2highx4 = sr2high * x4
-
-	h4 += r0lowx4
-	sr2lowx4 = sr2low * x4
-
-	h3 += sr3highx4
-	r0lowx2 = r0low * x2
-
-	h2 += sr3lowx4
-	r0highx2 = r0high * x2
-
-	h1 += sr2highx4
-	r1lowx2 = r1low * x2
-
-	h0 += sr2lowx4
-	r1highx2 = r1high * x2
-
-	h2 += r0lowx2
-	r2lowx2 = r2low * x2
-
-	h3 += r0highx2
-	r2highx2 = r2high * x2
-
-	h4 += r1lowx2
-	sr3lowx2 = sr3low * x2
-
-	h5 += r1highx2
-	sr3highx2 = sr3high * x2
-
-	h6 += r2lowx2
-
-	h7 += r2highx2
-
-	h0 += sr3lowx2
-
-	h1 += sr3highx2
-
-addatmost15bytes:
-
-	if l == 0 {
-		goto nomorebytes
-	}
-
-	lbelow2 = l - 2
-
-	lbelow3 = l - 3
-
-	lbelow2 >>= 31
-	lbelow4 = l - 4
-
-	m00 = uint32(m[p+0])
-	lbelow3 >>= 31
-	p += lbelow2
-
-	m01 = uint32(m[p+1])
-	lbelow4 >>= 31
-	p += lbelow3
-
-	m02 = uint32(m[p+2])
-	p += lbelow4
-	m0 = 2151
-
-	m03 = uint32(m[p+3])
-	m0 <<= 51
-	m1 = 2215
-
-	m0 += int64(m00)
-	m01 &^= uint32(lbelow2)
-
-	m02 &^= uint32(lbelow3)
-	m01 -= uint32(lbelow2)
-
-	m01 <<= 8
-	m03 &^= uint32(lbelow4)
-
-	m0 += int64(m01)
-	lbelow2 -= lbelow3
-
-	m02 += uint32(lbelow2)
-	lbelow3 -= lbelow4
-
-	m02 <<= 16
-	m03 += uint32(lbelow3)
-
-	m03 <<= 24
-	m0 += int64(m02)
-
-	m0 += int64(m03)
-	lbelow5 = l - 5
-
-	lbelow6 = l - 6
-	lbelow7 = l - 7
-
-	lbelow5 >>= 31
-	lbelow8 = l - 8
-
-	lbelow6 >>= 31
-	p += lbelow5
-
-	m10 = uint32(m[p+4])
-	lbelow7 >>= 31
-	p += lbelow6
-
-	m11 = uint32(m[p+5])
-	lbelow8 >>= 31
-	p += lbelow7
-
-	m12 = uint32(m[p+6])
-	m1 <<= 51
-	p += lbelow8
-
-	m13 = uint32(m[p+7])
-	m10 &^= uint32(lbelow5)
-	lbelow4 -= lbelow5
-
-	m10 += uint32(lbelow4)
-	lbelow5 -= lbelow6
-
-	m11 &^= uint32(lbelow6)
-	m11 += uint32(lbelow5)
-
-	m11 <<= 8
-	m1 += int64(m10)
-
-	m1 += int64(m11)
-	m12 &^= uint32(lbelow7)
-
-	lbelow6 -= lbelow7
-	m13 &^= uint32(lbelow8)
-
-	m12 += uint32(lbelow6)
-	lbelow7 -= lbelow8
-
-	m12 <<= 16
-	m13 += uint32(lbelow7)
-
-	m13 <<= 24
-	m1 += int64(m12)
-
-	m1 += int64(m13)
-	m2 = 2279
-
-	lbelow9 = l - 9
-	m3 = 2343
-
-	lbelow10 = l - 10
-	lbelow11 = l - 11
-
-	lbelow9 >>= 31
-	lbelow12 = l - 12
-
-	lbelow10 >>= 31
-	p += lbelow9
-
-	m20 = uint32(m[p+8])
-	lbelow11 >>= 31
-	p += lbelow10
-
-	m21 = uint32(m[p+9])
-	lbelow12 >>= 31
-	p += lbelow11
-
-	m22 = uint32(m[p+10])
-	m2 <<= 51
-	p += lbelow12
-
-	m23 = uint32(m[p+11])
-	m20 &^= uint32(lbelow9)
-	lbelow8 -= lbelow9
-
-	m20 += uint32(lbelow8)
-	lbelow9 -= lbelow10
-
-	m21 &^= uint32(lbelow10)
-	m21 += uint32(lbelow9)
-
-	m21 <<= 8
-	m2 += int64(m20)
-
-	m2 += int64(m21)
-	m22 &^= uint32(lbelow11)
-
-	lbelow10 -= lbelow11
-	m23 &^= uint32(lbelow12)
-
-	m22 += uint32(lbelow10)
-	lbelow11 -= lbelow12
-
-	m22 <<= 16
-	m23 += uint32(lbelow11)
-
-	m23 <<= 24
-	m2 += int64(m22)
-
-	m3 <<= 51
-	lbelow13 = l - 13
-
-	lbelow13 >>= 31
-	lbelow14 = l - 14
-
-	lbelow14 >>= 31
-	p += lbelow13
-	lbelow15 = l - 15
-
-	m30 = uint32(m[p+12])
-	lbelow15 >>= 31
-	p += lbelow14
-
-	m31 = uint32(m[p+13])
-	p += lbelow15
-	m2 += int64(m23)
-
-	m32 = uint32(m[p+14])
-	m30 &^= uint32(lbelow13)
-	lbelow12 -= lbelow13
-
-	m30 += uint32(lbelow12)
-	lbelow13 -= lbelow14
-
-	m3 += int64(m30)
-	m31 &^= uint32(lbelow14)
-
-	m31 += uint32(lbelow13)
-	m32 &^= uint32(lbelow15)
-
-	m31 <<= 8
-	lbelow14 -= lbelow15
-
-	m3 += int64(m31)
-	m32 += uint32(lbelow14)
-	d0 = m0
-
-	m32 <<= 16
-	m33 = uint64(lbelow15 + 1)
-	d1 = m1
-
-	m33 <<= 24
-	m3 += int64(m32)
-	d2 = m2
-
-	m3 += int64(m33)
-	d3 = m3
-
-	z3 = math.Float64frombits(uint64(d3))
-
-	z2 = math.Float64frombits(uint64(d2))
-
-	z1 = math.Float64frombits(uint64(d1))
-
-	z0 = math.Float64frombits(uint64(d0))
-
-	z3 -= alpha96
-
-	z2 -= alpha64
-
-	z1 -= alpha32
-
-	z0 -= alpha0
-
-	h5 += z3
-
-	h3 += z2
-
-	h1 += z1
-
-	h0 += z0
-
-	y7 = h7 + alpha130
-
-	y6 = h6 + alpha130
-
-	y1 = h1 + alpha32
-
-	y0 = h0 + alpha32
-
-	y7 -= alpha130
-
-	y6 -= alpha130
-
-	y1 -= alpha32
-
-	y0 -= alpha32
-
-	y5 = h5 + alpha96
-
-	y4 = h4 + alpha96
-
-	x7 = h7 - y7
-	y7 *= scale
-
-	x6 = h6 - y6
-	y6 *= scale
-
-	x1 = h1 - y1
-
-	x0 = h0 - y0
-
-	y5 -= alpha96
-
-	y4 -= alpha96
-
-	x1 += y7
-
-	x0 += y6
-
-	x7 += y5
-
-	x6 += y4
-
-	y3 = h3 + alpha64
-
-	y2 = h2 + alpha64
-
-	x0 += x1
-
-	x6 += x7
-
-	y3 -= alpha64
-	r3low = r3low_stack
-
-	y2 -= alpha64
-	r0low = r0low_stack
-
-	x5 = h5 - y5
-	r3lowx0 = r3low * x0
-	r3high = r3high_stack
-
-	x4 = h4 - y4
-	r0lowx6 = r0low * x6
-	r0high = r0high_stack
-
-	x3 = h3 - y3
-	r3highx0 = r3high * x0
-	sr1low = sr1low_stack
-
-	x2 = h2 - y2
-	r0highx6 = r0high * x6
-	sr1high = sr1high_stack
-
-	x5 += y3
-	r0lowx0 = r0low * x0
-	r1low = r1low_stack
-
-	h6 = r3lowx0 + r0lowx6
-	sr1lowx6 = sr1low * x6
-	r1high = r1high_stack
-
-	x4 += y2
-	r0highx0 = r0high * x0
-	sr2low = sr2low_stack
-
-	h7 = r3highx0 + r0highx6
-	sr1highx6 = sr1high * x6
-	sr2high = sr2high_stack
-
-	x3 += y1
-	r1lowx0 = r1low * x0
-	r2low = r2low_stack
-
-	h0 = r0lowx0 + sr1lowx6
-	sr2lowx6 = sr2low * x6
-	r2high = r2high_stack
-
-	x2 += y0
-	r1highx0 = r1high * x0
-	sr3low = sr3low_stack
-
-	h1 = r0highx0 + sr1highx6
-	sr2highx6 = sr2high * x6
-	sr3high = sr3high_stack
-
-	x4 += x5
-	r2lowx0 = r2low * x0
-
-	h2 = r1lowx0 + sr2lowx6
-	sr3lowx6 = sr3low * x6
-
-	x2 += x3
-	r2highx0 = r2high * x0
-
-	h3 = r1highx0 + sr2highx6
-	sr3highx6 = sr3high * x6
-
-	r1highx4 = r1high * x4
-
-	h4 = r2lowx0 + sr3lowx6
-	r1lowx4 = r1low * x4
-
-	r0highx4 = r0high * x4
-
-	h5 = r2highx0 + sr3highx6
-	r0lowx4 = r0low * x4
-
-	h7 += r1highx4
-	sr3highx4 = sr3high * x4
-
-	h6 += r1lowx4
-	sr3lowx4 = sr3low * x4
-
-	h5 += r0highx4
-	sr2highx4 = sr2high * x4
-
-	h4 += r0lowx4
-	sr2lowx4 = sr2low * x4
-
-	h3 += sr3highx4
-	r0lowx2 = r0low * x2
-
-	h2 += sr3lowx4
-	r0highx2 = r0high * x2
-
-	h1 += sr2highx4
-	r1lowx2 = r1low * x2
-
-	h0 += sr2lowx4
-	r1highx2 = r1high * x2
-
-	h2 += r0lowx2
-	r2lowx2 = r2low * x2
-
-	h3 += r0highx2
-	r2highx2 = r2high * x2
-
-	h4 += r1lowx2
-	sr3lowx2 = sr3low * x2
-
-	h5 += r1highx2
-	sr3highx2 = sr3high * x2
-
-	h6 += r2lowx2
-
-	h7 += r2highx2
-
-	h0 += sr3lowx2
-
-	h1 += sr3highx2
-
-nomorebytes:
-
-	y7 = h7 + alpha130
-
-	y0 = h0 + alpha32
-
-	y1 = h1 + alpha32
-
-	y2 = h2 + alpha64
-
-	y7 -= alpha130
-
-	y3 = h3 + alpha64
-
-	y4 = h4 + alpha96
-
-	y5 = h5 + alpha96
-
-	x7 = h7 - y7
-	y7 *= scale
-
-	y0 -= alpha32
-
-	y1 -= alpha32
-
-	y2 -= alpha64
-
-	h6 += x7
-
-	y3 -= alpha64
-
-	y4 -= alpha96
-
-	y5 -= alpha96
-
-	y6 = h6 + alpha130
-
-	x0 = h0 - y0
-
-	x1 = h1 - y1
-
-	x2 = h2 - y2
-
-	y6 -= alpha130
-
-	x0 += y7
-
-	x3 = h3 - y3
-
-	x4 = h4 - y4
-
-	x5 = h5 - y5
-
-	x6 = h6 - y6
-
-	y6 *= scale
-
-	x2 += y0
-
-	x3 += y1
-
-	x4 += y2
-
-	x0 += y6
-
-	x5 += y3
-
-	x6 += y4
-
-	x2 += x3
-
-	x0 += x1
-
-	x4 += x5
-
-	x6 += y5
-
-	x2 += offset1
-	d1 = int64(math.Float64bits(x2))
-
-	x0 += offset0
-	d0 = int64(math.Float64bits(x0))
-
-	x4 += offset2
-	d2 = int64(math.Float64bits(x4))
-
-	x6 += offset3
-	d3 = int64(math.Float64bits(x6))
-
-	f0 = uint64(d0)
-
-	f1 = uint64(d1)
-	bits32 = math.MaxUint64
-
-	f2 = uint64(d2)
-	bits32 >>= 32
-
-	f3 = uint64(d3)
-	f = f0 >> 32
-
-	f0 &= bits32
-	f &= 255
-
-	f1 += f
-	g0 = f0 + 5
-
-	g = g0 >> 32
-	g0 &= bits32
-
-	f = f1 >> 32
-	f1 &= bits32
-
-	f &= 255
-	g1 = f1 + g
-
-	g = g1 >> 32
-	f2 += f
-
-	f = f2 >> 32
-	g1 &= bits32
-
-	f2 &= bits32
-	f &= 255
-
-	f3 += f
-	g2 = f2 + g
-
-	g = g2 >> 32
-	g2 &= bits32
-
-	f4 = f3 >> 32
-	f3 &= bits32
-
-	f4 &= 255
-	g3 = f3 + g
-
-	g = g3 >> 32
-	g3 &= bits32
-
-	g4 = f4 + g
-
-	g4 = g4 - 4
-	s00 = uint32(s[0])
-
-	f = uint64(int64(g4) >> 63)
-	s01 = uint32(s[1])
-
-	f0 &= f
-	g0 &^= f
-	s02 = uint32(s[2])
-
-	f1 &= f
-	f0 |= g0
-	s03 = uint32(s[3])
-
-	g1 &^= f
-	f2 &= f
-	s10 = uint32(s[4])
-
-	f3 &= f
-	g2 &^= f
-	s11 = uint32(s[5])
-
-	g3 &^= f
-	f1 |= g1
-	s12 = uint32(s[6])
-
-	f2 |= g2
-	f3 |= g3
-	s13 = uint32(s[7])
-
-	s01 <<= 8
-	f0 += uint64(s00)
-	s20 = uint32(s[8])
-
-	s02 <<= 16
-	f0 += uint64(s01)
-	s21 = uint32(s[9])
-
-	s03 <<= 24
-	f0 += uint64(s02)
-	s22 = uint32(s[10])
-
-	s11 <<= 8
-	f1 += uint64(s10)
-	s23 = uint32(s[11])
-
-	s12 <<= 16
-	f1 += uint64(s11)
-	s30 = uint32(s[12])
-
-	s13 <<= 24
-	f1 += uint64(s12)
-	s31 = uint32(s[13])
-
-	f0 += uint64(s03)
-	f1 += uint64(s13)
-	s32 = uint32(s[14])
-
-	s21 <<= 8
-	f2 += uint64(s20)
-	s33 = uint32(s[15])
-
-	s22 <<= 16
-	f2 += uint64(s21)
-
-	s23 <<= 24
-	f2 += uint64(s22)
-
-	s31 <<= 8
-	f3 += uint64(s30)
-
-	s32 <<= 16
-	f3 += uint64(s31)
-
-	s33 <<= 24
-	f3 += uint64(s32)
-
-	f2 += uint64(s23)
-	f3 += uint64(s33)
-
-	out[0] = byte(f0)
-	f0 >>= 8
-	out[1] = byte(f0)
-	f0 >>= 8
-	out[2] = byte(f0)
-	f0 >>= 8
-	out[3] = byte(f0)
-	f0 >>= 8
-	f1 += f0
-
-	out[4] = byte(f1)
-	f1 >>= 8
-	out[5] = byte(f1)
-	f1 >>= 8
-	out[6] = byte(f1)
-	f1 >>= 8
-	out[7] = byte(f1)
-	f1 >>= 8
-	f2 += f1
-
-	out[8] = byte(f2)
-	f2 >>= 8
-	out[9] = byte(f2)
-	f2 >>= 8
-	out[10] = byte(f2)
-	f2 >>= 8
-	out[11] = byte(f2)
-	f2 >>= 8
-	f3 += f2
-
-	out[12] = byte(f3)
-	f3 >>= 8
-	out[13] = byte(f3)
-	f3 >>= 8
-	out[14] = byte(f3)
-	f3 >>= 8
-	out[15] = byte(f3)
+	binary.LittleEndian.PutUint32(out[0:], h0)
+	binary.LittleEndian.PutUint32(out[4:], h1)
+	binary.LittleEndian.PutUint32(out[8:], h2)
+	binary.LittleEndian.PutUint32(out[12:], h3)
 }
diff --git a/libgo/go/golang_org/x/net/http2/hpack/encode.go b/libgo/go/golang_org/x/net/http2/hpack/encode.go
index f9bb033..54726c2 100644
--- a/libgo/go/golang_org/x/net/http2/hpack/encode.go
+++ b/libgo/go/golang_org/x/net/http2/hpack/encode.go
@@ -39,13 +39,14 @@
 		tableSizeUpdate: false,
 		w:               w,
 	}
+	e.dynTab.table.init()
 	e.dynTab.setMaxSize(initialHeaderTableSize)
 	return e
 }
 
 // WriteField encodes f into a single Write to e's underlying Writer.
 // This function may also produce bytes for "Header Table Size Update"
-// if necessary.  If produced, it is done before encoding f.
+// if necessary. If produced, it is done before encoding f.
 func (e *Encoder) WriteField(f HeaderField) error {
 	e.buf = e.buf[:0]
 
@@ -88,29 +89,17 @@
 // only name matches, i points to that index and nameValueMatch
 // becomes false.
 func (e *Encoder) searchTable(f HeaderField) (i uint64, nameValueMatch bool) {
-	for idx, hf := range staticTable {
-		if !constantTimeStringCompare(hf.Name, f.Name) {
-			continue
-		}
-		if i == 0 {
-			i = uint64(idx + 1)
-		}
-		if f.Sensitive {
-			continue
-		}
-		if !constantTimeStringCompare(hf.Value, f.Value) {
-			continue
-		}
-		i = uint64(idx + 1)
-		nameValueMatch = true
-		return
+	i, nameValueMatch = staticTable.search(f)
+	if nameValueMatch {
+		return i, true
 	}
 
-	j, nameValueMatch := e.dynTab.search(f)
+	j, nameValueMatch := e.dynTab.table.search(f)
 	if nameValueMatch || (i == 0 && j != 0) {
-		i = j + uint64(len(staticTable))
+		return j + uint64(staticTable.len()), nameValueMatch
 	}
-	return
+
+	return i, false
 }
 
 // SetMaxDynamicTableSize changes the dynamic header table size to v.
diff --git a/libgo/go/golang_org/x/net/http2/hpack/encode_test.go b/libgo/go/golang_org/x/net/http2/hpack/encode_test.go
index 92286f3..05f12db 100644
--- a/libgo/go/golang_org/x/net/http2/hpack/encode_test.go
+++ b/libgo/go/golang_org/x/net/http2/hpack/encode_test.go
@@ -7,6 +7,8 @@
 import (
 	"bytes"
 	"encoding/hex"
+	"fmt"
+	"math/rand"
 	"reflect"
 	"strings"
 	"testing"
@@ -101,17 +103,20 @@
 		wantMatch bool
 	}{
 		// Name and Value match
-		{pair("foo", "bar"), uint64(len(staticTable) + 3), true},
-		{pair("blake", "miz"), uint64(len(staticTable) + 2), true},
+		{pair("foo", "bar"), uint64(staticTable.len()) + 3, true},
+		{pair("blake", "miz"), uint64(staticTable.len()) + 2, true},
 		{pair(":method", "GET"), 2, true},
 
-		// Only name match because Sensitive == true
-		{HeaderField{":method", "GET", true}, 2, false},
+		// Only name match because Sensitive == true. This is allowed to match
+		// any ":method" entry. The current implementation uses the last entry
+		// added in newStaticTable.
+		{HeaderField{":method", "GET", true}, 3, false},
 
 		// Only Name matches
-		{pair("foo", "..."), uint64(len(staticTable) + 3), false},
-		{pair("blake", "..."), uint64(len(staticTable) + 2), false},
-		{pair(":method", "..."), 2, false},
+		{pair("foo", "..."), uint64(staticTable.len()) + 3, false},
+		{pair("blake", "..."), uint64(staticTable.len()) + 2, false},
+		// As before, this is allowed to match any ":method" entry.
+		{pair(":method", "..."), 3, false},
 
 		// None match
 		{pair("foo-", "bar"), 0, false},
@@ -328,3 +333,54 @@
 func removeSpace(s string) string {
 	return strings.Replace(s, " ", "", -1)
 }
+
+func BenchmarkEncoderSearchTable(b *testing.B) {
+	e := NewEncoder(nil)
+
+	// A sample of possible header fields.
+	// This is not based on any actual data from HTTP/2 traces.
+	var possible []HeaderField
+	for _, f := range staticTable.ents {
+		if f.Value == "" {
+			possible = append(possible, f)
+			continue
+		}
+		// Generate 5 random values, except for cookie and set-cookie,
+		// which we know can have many values in practice.
+		num := 5
+		if f.Name == "cookie" || f.Name == "set-cookie" {
+			num = 25
+		}
+		for i := 0; i < num; i++ {
+			f.Value = fmt.Sprintf("%s-%d", f.Name, i)
+			possible = append(possible, f)
+		}
+	}
+	for k := 0; k < 10; k++ {
+		f := HeaderField{
+			Name:      fmt.Sprintf("x-header-%d", k),
+			Sensitive: rand.Int()%2 == 0,
+		}
+		for i := 0; i < 5; i++ {
+			f.Value = fmt.Sprintf("%s-%d", f.Name, i)
+			possible = append(possible, f)
+		}
+	}
+
+	// Add a random sample to the dynamic table. This very loosely simulates
+	// a history of 100 requests with 20 header fields per request.
+	for r := 0; r < 100*20; r++ {
+		f := possible[rand.Int31n(int32(len(possible)))]
+		// Skip if this is in the staticTable verbatim.
+		if _, has := staticTable.search(f); !has {
+			e.dynTab.add(f)
+		}
+	}
+
+	b.ResetTimer()
+	for n := 0; n < b.N; n++ {
+		for _, f := range possible {
+			e.searchTable(f)
+		}
+	}
+}
diff --git a/libgo/go/golang_org/x/net/http2/hpack/hpack.go b/libgo/go/golang_org/x/net/http2/hpack/hpack.go
index 8aa197a..176644a 100644
--- a/libgo/go/golang_org/x/net/http2/hpack/hpack.go
+++ b/libgo/go/golang_org/x/net/http2/hpack/hpack.go
@@ -57,11 +57,11 @@
 	return fmt.Sprintf("header field %q = %q%s", hf.Name, hf.Value, suffix)
 }
 
-// Size returns the size of an entry per RFC 7540 section 5.2.
+// Size returns the size of an entry per RFC 7541 section 4.1.
 func (hf HeaderField) Size() uint32 {
 	// http://http2.github.io/http2-spec/compression.html#rfc.section.4.1
 	// "The size of the dynamic table is the sum of the size of
-	// its entries.  The size of an entry is the sum of its name's
+	// its entries. The size of an entry is the sum of its name's
 	// length in octets (as defined in Section 5.2), its value's
 	// length in octets (see Section 5.2), plus 32.  The size of
 	// an entry is calculated using the length of the name and
@@ -102,6 +102,7 @@
 		emit:        emitFunc,
 		emitEnabled: true,
 	}
+	d.dynTab.table.init()
 	d.dynTab.allowedMaxSize = maxDynamicTableSize
 	d.dynTab.setMaxSize(maxDynamicTableSize)
 	return d
@@ -154,12 +155,9 @@
 }
 
 type dynamicTable struct {
-	// ents is the FIFO described at
 	// http://http2.github.io/http2-spec/compression.html#rfc.section.2.3.2
-	// The newest (low index) is append at the end, and items are
-	// evicted from the front.
-	ents           []HeaderField
-	size           uint32
+	table          headerFieldTable
+	size           uint32 // in bytes
 	maxSize        uint32 // current maxSize
 	allowedMaxSize uint32 // maxSize may go up to this, inclusive
 }
@@ -169,95 +167,45 @@
 	dt.evict()
 }
 
-// TODO: change dynamicTable to be a struct with a slice and a size int field,
-// per http://http2.github.io/http2-spec/compression.html#rfc.section.4.1:
-//
-//
-// Then make add increment the size. maybe the max size should move from Decoder to
-// dynamicTable and add should return an ok bool if there was enough space.
-//
-// Later we'll need a remove operation on dynamicTable.
-
 func (dt *dynamicTable) add(f HeaderField) {
-	dt.ents = append(dt.ents, f)
+	dt.table.addEntry(f)
 	dt.size += f.Size()
 	dt.evict()
 }
 
-// If we're too big, evict old stuff (front of the slice)
+// If we're too big, evict old stuff.
 func (dt *dynamicTable) evict() {
-	base := dt.ents // keep base pointer of slice
-	for dt.size > dt.maxSize {
-		dt.size -= dt.ents[0].Size()
-		dt.ents = dt.ents[1:]
+	var n int
+	for dt.size > dt.maxSize && n < dt.table.len() {
+		dt.size -= dt.table.ents[n].Size()
+		n++
 	}
-
-	// Shift slice contents down if we evicted things.
-	if len(dt.ents) != len(base) {
-		copy(base, dt.ents)
-		dt.ents = base[:len(dt.ents)]
-	}
-}
-
-// constantTimeStringCompare compares string a and b in a constant
-// time manner.
-func constantTimeStringCompare(a, b string) bool {
-	if len(a) != len(b) {
-		return false
-	}
-
-	c := byte(0)
-
-	for i := 0; i < len(a); i++ {
-		c |= a[i] ^ b[i]
-	}
-
-	return c == 0
-}
-
-// Search searches f in the table. The return value i is 0 if there is
-// no name match. If there is name match or name/value match, i is the
-// index of that entry (1-based). If both name and value match,
-// nameValueMatch becomes true.
-func (dt *dynamicTable) search(f HeaderField) (i uint64, nameValueMatch bool) {
-	l := len(dt.ents)
-	for j := l - 1; j >= 0; j-- {
-		ent := dt.ents[j]
-		if !constantTimeStringCompare(ent.Name, f.Name) {
-			continue
-		}
-		if i == 0 {
-			i = uint64(l - j)
-		}
-		if f.Sensitive {
-			continue
-		}
-		if !constantTimeStringCompare(ent.Value, f.Value) {
-			continue
-		}
-		i = uint64(l - j)
-		nameValueMatch = true
-		return
-	}
-	return
+	dt.table.evictOldest(n)
 }
 
 func (d *Decoder) maxTableIndex() int {
-	return len(d.dynTab.ents) + len(staticTable)
+	// This should never overflow. RFC 7540 Section 6.5.2 limits the size of
+	// the dynamic table to 2^32 bytes, where each entry will occupy more than
+	// one byte. Further, the staticTable has a fixed, small length.
+	return d.dynTab.table.len() + staticTable.len()
 }
 
 func (d *Decoder) at(i uint64) (hf HeaderField, ok bool) {
-	if i < 1 {
+	// See Section 2.3.3.
+	if i == 0 {
 		return
 	}
+	if i <= uint64(staticTable.len()) {
+		return staticTable.ents[i-1], true
+	}
 	if i > uint64(d.maxTableIndex()) {
 		return
 	}
-	if i <= uint64(len(staticTable)) {
-		return staticTable[i-1], true
-	}
-	dents := d.dynTab.ents
-	return dents[len(dents)-(int(i)-len(staticTable))], true
+	// In the dynamic table, newer entries have lower indices.
+	// However, dt.ents[0] is the oldest entry. Hence, dt.ents is
+	// the reversed dynamic table.
+	dt := d.dynTab.table
+	return dt.ents[dt.len()-(int(i)-staticTable.len())], true
 }
 
 // Decode decodes an entire block.
@@ -307,7 +255,7 @@
 		err = d.parseHeaderFieldRepr()
 		if err == errNeedMore {
 			// Extra paranoia, making sure saveBuf won't
-			// get too large.  All the varint and string
+			// get too large. All the varint and string
 			// reading code earlier should already catch
 			// overlong things and return ErrStringLength,
 			// but keep this as a last resort.
diff --git a/libgo/go/golang_org/x/net/http2/hpack/hpack_test.go b/libgo/go/golang_org/x/net/http2/hpack/hpack_test.go
index 4c7b17b..bc7f476 100644
--- a/libgo/go/golang_org/x/net/http2/hpack/hpack_test.go
+++ b/libgo/go/golang_org/x/net/http2/hpack/hpack_test.go
@@ -5,117 +5,16 @@
 package hpack
 
 import (
-	"bufio"
 	"bytes"
 	"encoding/hex"
 	"fmt"
 	"math/rand"
 	"reflect"
-	"regexp"
-	"strconv"
 	"strings"
 	"testing"
 	"time"
 )
 
-func TestStaticTable(t *testing.T) {
-	fromSpec := `
-          +-------+-----------------------------+---------------+
-          | 1     | :authority                  |               |
-          | 2     | :method                     | GET           |
-          | 3     | :method                     | POST          |
-          | 4     | :path                       | /             |
-          | 5     | :path                       | /index.html   |
-          | 6     | :scheme                     | http          |
-          | 7     | :scheme                     | https         |
-          | 8     | :status                     | 200           |
-          | 9     | :status                     | 204           |
-          | 10    | :status                     | 206           |
-          | 11    | :status                     | 304           |
-          | 12    | :status                     | 400           |
-          | 13    | :status                     | 404           |
-          | 14    | :status                     | 500           |
-          | 15    | accept-charset              |               |
-          | 16    | accept-encoding             | gzip, deflate |
-          | 17    | accept-language             |               |
-          | 18    | accept-ranges               |               |
-          | 19    | accept                      |               |
-          | 20    | access-control-allow-origin |               |
-          | 21    | age                         |               |
-          | 22    | allow                       |               |
-          | 23    | authorization               |               |
-          | 24    | cache-control               |               |
-          | 25    | content-disposition         |               |
-          | 26    | content-encoding            |               |
-          | 27    | content-language            |               |
-          | 28    | content-length              |               |
-          | 29    | content-location            |               |
-          | 30    | content-range               |               |
-          | 31    | content-type                |               |
-          | 32    | cookie                      |               |
-          | 33    | date                        |               |
-          | 34    | etag                        |               |
-          | 35    | expect                      |               |
-          | 36    | expires                     |               |
-          | 37    | from                        |               |
-          | 38    | host                        |               |
-          | 39    | if-match                    |               |
-          | 40    | if-modified-since           |               |
-          | 41    | if-none-match               |               |
-          | 42    | if-range                    |               |
-          | 43    | if-unmodified-since         |               |
-          | 44    | last-modified               |               |
-          | 45    | link                        |               |
-          | 46    | location                    |               |
-          | 47    | max-forwards                |               |
-          | 48    | proxy-authenticate          |               |
-          | 49    | proxy-authorization         |               |
-          | 50    | range                       |               |
-          | 51    | referer                     |               |
-          | 52    | refresh                     |               |
-          | 53    | retry-after                 |               |
-          | 54    | server                      |               |
-          | 55    | set-cookie                  |               |
-          | 56    | strict-transport-security   |               |
-          | 57    | transfer-encoding           |               |
-          | 58    | user-agent                  |               |
-          | 59    | vary                        |               |
-          | 60    | via                         |               |
-          | 61    | www-authenticate            |               |
-          +-------+-----------------------------+---------------+
-`
-	bs := bufio.NewScanner(strings.NewReader(fromSpec))
-	re := regexp.MustCompile(`\| (\d+)\s+\| (\S+)\s*\| (\S(.*\S)?)?\s+\|`)
-	for bs.Scan() {
-		l := bs.Text()
-		if !strings.Contains(l, "|") {
-			continue
-		}
-		m := re.FindStringSubmatch(l)
-		if m == nil {
-			continue
-		}
-		i, err := strconv.Atoi(m[1])
-		if err != nil {
-			t.Errorf("Bogus integer on line %q", l)
-			continue
-		}
-		if i < 1 || i > len(staticTable) {
-			t.Errorf("Bogus index %d on line %q", i, l)
-			continue
-		}
-		if got, want := staticTable[i-1].Name, m[2]; got != want {
-			t.Errorf("header index %d name = %q; want %q", i, got, want)
-		}
-		if got, want := staticTable[i-1].Value, m[3]; got != want {
-			t.Errorf("header index %d value = %q; want %q", i, got, want)
-		}
-	}
-	if err := bs.Err(); err != nil {
-		t.Error(err)
-	}
-}
-
 func (d *Decoder) mustAt(idx int) HeaderField {
 	if hf, ok := d.at(uint64(idx)); !ok {
 		panic(fmt.Sprintf("bogus index %d", idx))
@@ -132,10 +31,10 @@
 	}
 	d.dynTab.add(pair("foo", "bar"))
 	d.dynTab.add(pair("blake", "miz"))
-	if got, want := at(len(staticTable)+1), (pair("blake", "miz")); got != want {
+	if got, want := at(staticTable.len()+1), (pair("blake", "miz")); got != want {
 		t.Errorf("at(dyn 1) = %v; want %v", got, want)
 	}
-	if got, want := at(len(staticTable)+2), (pair("foo", "bar")); got != want {
+	if got, want := at(staticTable.len()+2), (pair("foo", "bar")); got != want {
 		t.Errorf("at(dyn 2) = %v; want %v", got, want)
 	}
 	if got, want := at(3), (pair(":method", "POST")); got != want {
@@ -143,41 +42,6 @@
 	}
 }
 
-func TestDynamicTableSearch(t *testing.T) {
-	dt := dynamicTable{}
-	dt.setMaxSize(4096)
-
-	dt.add(pair("foo", "bar"))
-	dt.add(pair("blake", "miz"))
-	dt.add(pair(":method", "GET"))
-
-	tests := []struct {
-		hf        HeaderField
-		wantI     uint64
-		wantMatch bool
-	}{
-		// Name and Value match
-		{pair("foo", "bar"), 3, true},
-		{pair(":method", "GET"), 1, true},
-
-		// Only name match because of Sensitive == true
-		{HeaderField{"blake", "miz", true}, 2, false},
-
-		// Only Name matches
-		{pair("foo", "..."), 3, false},
-		{pair("blake", "..."), 2, false},
-		{pair(":method", "..."), 1, false},
-
-		// None match
-		{pair("foo-", "bar"), 0, false},
-	}
-	for _, tt := range tests {
-		if gotI, gotMatch := dt.search(tt.hf); gotI != tt.wantI || gotMatch != tt.wantMatch {
-			t.Errorf("d.search(%+v) = %v, %v; want %v, %v", tt.hf, gotI, gotMatch, tt.wantI, tt.wantMatch)
-		}
-	}
-}
-
 func TestDynamicTableSizeEvict(t *testing.T) {
 	d := NewDecoder(4096, nil)
 	if want := uint32(0); d.dynTab.size != want {
@@ -196,7 +60,7 @@
 	if want := uint32(6 + 32); d.dynTab.size != want {
 		t.Fatalf("after setMaxSize, size = %d; want %d", d.dynTab.size, want)
 	}
-	if got, want := d.mustAt(len(staticTable)+1), (pair("foo", "bar")); got != want {
+	if got, want := d.mustAt(staticTable.len()+1), (pair("foo", "bar")); got != want {
 		t.Errorf("at(dyn 1) = %v; want %v", got, want)
 	}
 	add(pair("long", strings.Repeat("x", 500)))
@@ -255,9 +119,9 @@
 }
 
 func (dt *dynamicTable) reverseCopy() (hf []HeaderField) {
-	hf = make([]HeaderField, len(dt.ents))
+	hf = make([]HeaderField, len(dt.table.ents))
 	for i := range hf {
-		hf[i] = dt.ents[len(dt.ents)-1-i]
+		hf[i] = dt.table.ents[len(dt.table.ents)-1-i]
 	}
 	return
 }
@@ -784,6 +648,10 @@
 	}
 }
 
+func pair(name, value string) HeaderField {
+	return HeaderField{Name: name, Value: value}
+}
+
 func dehex(s string) []byte {
 	s = strings.Replace(s, " ", "", -1)
 	s = strings.Replace(s, "\n", "", -1)
diff --git a/libgo/go/golang_org/x/net/http2/hpack/tables.go b/libgo/go/golang_org/x/net/http2/hpack/tables.go
index b9283a0..8bd975d 100644
--- a/libgo/go/golang_org/x/net/http2/hpack/tables.go
+++ b/libgo/go/golang_org/x/net/http2/hpack/tables.go
@@ -4,73 +4,200 @@
 
 package hpack
 
-func pair(name, value string) HeaderField {
-	return HeaderField{Name: name, Value: value}
+import (
+	"fmt"
+)
+
+// headerFieldTable implements a list of HeaderFields.
+// This is used to implement the static and dynamic tables.
+type headerFieldTable struct {
+	// For static tables, entries are never evicted.
+	//
+	// For dynamic tables, entries are evicted from ents[0] and added to the end.
+	// Each entry has a unique id that starts at one and increments for each
+	// entry that is added. This unique id is stable across evictions, meaning
+	// it can be used as a pointer to a specific entry. As in hpack, unique ids
+	// are 1-based. The unique id for ents[k] is k + evictCount + 1.
+	//
+	// Zero is not a valid unique id.
+	//
+	// evictCount should not overflow in any remotely practical situation. In
+	// practice, we will have one dynamic table per HTTP/2 connection. If we
+	// assume a very powerful server that handles 1M QPS per connection and each
+	// request adds (then evicts) 100 entries from the table, it would still take
+	// 2M years for evictCount to overflow.
+	ents       []HeaderField
+	evictCount uint64
+
+	// byName maps a HeaderField name to the unique id of the newest entry with
+	// the same name. See above for a definition of "unique id".
+	byName map[string]uint64
+
+	// byNameValue maps a HeaderField name/value pair to the unique id of the newest
+	// entry with the same name and value. See above for a definition of "unique id".
+	byNameValue map[pairNameValue]uint64
+}
+
+type pairNameValue struct {
+	name, value string
+}
+
+func (t *headerFieldTable) init() {
+	t.byName = make(map[string]uint64)
+	t.byNameValue = make(map[pairNameValue]uint64)
+}
+
+// len reports the number of entries in the table.
+func (t *headerFieldTable) len() int {
+	return len(t.ents)
+}
+
+// addEntry adds a new entry.
+func (t *headerFieldTable) addEntry(f HeaderField) {
+	id := uint64(t.len()) + t.evictCount + 1
+	t.byName[f.Name] = id
+	t.byNameValue[pairNameValue{f.Name, f.Value}] = id
+	t.ents = append(t.ents, f)
+}
+
+// evictOldest evicts the n oldest entries in the table.
+func (t *headerFieldTable) evictOldest(n int) {
+	if n > t.len() {
+		panic(fmt.Sprintf("evictOldest(%v) on table with %v entries", n, t.len()))
+	}
+	for k := 0; k < n; k++ {
+		f := t.ents[k]
+		id := t.evictCount + uint64(k) + 1
+		if t.byName[f.Name] == id {
+			delete(t.byName, f.Name)
+		}
+		if p := (pairNameValue{f.Name, f.Value}); t.byNameValue[p] == id {
+			delete(t.byNameValue, p)
+		}
+	}
+	copy(t.ents, t.ents[n:])
+	for k := t.len() - n; k < t.len(); k++ {
+		t.ents[k] = HeaderField{} // so strings can be garbage collected
+	}
+	t.ents = t.ents[:t.len()-n]
+	if t.evictCount+uint64(n) < t.evictCount {
+		panic("evictCount overflow")
+	}
+	t.evictCount += uint64(n)
+}
+
+// search finds f in the table. If there is no match, i is 0.
+// If both name and value match, i is the matched index and nameValueMatch
+// becomes true. If only name matches, i points to that index and
+// nameValueMatch becomes false.
+//
+// The returned index is a 1-based HPACK index. For dynamic tables, HPACK says
+// that index 1 should be the newest entry, but t.ents[0] is the oldest entry,
+// meaning t.ents is reversed for dynamic tables. Hence, when t is a dynamic
+// table, the return value i actually refers to the entry t.ents[t.len()-i].
+//
+// All tables are assumed to be a dynamic tables except for the global
+// staticTable pointer.
+//
+// See Section 2.3.3.
+func (t *headerFieldTable) search(f HeaderField) (i uint64, nameValueMatch bool) {
+	if !f.Sensitive {
+		if id := t.byNameValue[pairNameValue{f.Name, f.Value}]; id != 0 {
+			return t.idToIndex(id), true
+		}
+	}
+	if id := t.byName[f.Name]; id != 0 {
+		return t.idToIndex(id), false
+	}
+	return 0, false
+}
+
+// idToIndex converts a unique id to an HPACK index.
+// See Section 2.3.3.
+func (t *headerFieldTable) idToIndex(id uint64) uint64 {
+	if id <= t.evictCount {
+		panic(fmt.Sprintf("id (%v) <= evictCount (%v)", id, t.evictCount))
+	}
+	k := id - t.evictCount - 1 // convert id to an index t.ents[k]
+	if t != staticTable {
+		return uint64(t.len()) - k // dynamic table
+	}
+	return k + 1
 }
 
 // http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-07#appendix-B
-var staticTable = [...]HeaderField{
-	pair(":authority", ""), // index 1 (1-based)
-	pair(":method", "GET"),
-	pair(":method", "POST"),
-	pair(":path", "/"),
-	pair(":path", "/index.html"),
-	pair(":scheme", "http"),
-	pair(":scheme", "https"),
-	pair(":status", "200"),
-	pair(":status", "204"),
-	pair(":status", "206"),
-	pair(":status", "304"),
-	pair(":status", "400"),
-	pair(":status", "404"),
-	pair(":status", "500"),
-	pair("accept-charset", ""),
-	pair("accept-encoding", "gzip, deflate"),
-	pair("accept-language", ""),
-	pair("accept-ranges", ""),
-	pair("accept", ""),
-	pair("access-control-allow-origin", ""),
-	pair("age", ""),
-	pair("allow", ""),
-	pair("authorization", ""),
-	pair("cache-control", ""),
-	pair("content-disposition", ""),
-	pair("content-encoding", ""),
-	pair("content-language", ""),
-	pair("content-length", ""),
-	pair("content-location", ""),
-	pair("content-range", ""),
-	pair("content-type", ""),
-	pair("cookie", ""),
-	pair("date", ""),
-	pair("etag", ""),
-	pair("expect", ""),
-	pair("expires", ""),
-	pair("from", ""),
-	pair("host", ""),
-	pair("if-match", ""),
-	pair("if-modified-since", ""),
-	pair("if-none-match", ""),
-	pair("if-range", ""),
-	pair("if-unmodified-since", ""),
-	pair("last-modified", ""),
-	pair("link", ""),
-	pair("location", ""),
-	pair("max-forwards", ""),
-	pair("proxy-authenticate", ""),
-	pair("proxy-authorization", ""),
-	pair("range", ""),
-	pair("referer", ""),
-	pair("refresh", ""),
-	pair("retry-after", ""),
-	pair("server", ""),
-	pair("set-cookie", ""),
-	pair("strict-transport-security", ""),
-	pair("transfer-encoding", ""),
-	pair("user-agent", ""),
-	pair("vary", ""),
-	pair("via", ""),
-	pair("www-authenticate", ""),
+var staticTable = newStaticTable()
+var staticTableEntries = [...]HeaderField{
+	HeaderField{Name: ":authority"},
+	HeaderField{Name: ":method", Value: "GET"},
+	HeaderField{Name: ":method", Value: "POST"},
+	HeaderField{Name: ":path", Value: "/"},
+	HeaderField{Name: ":path", Value: "/index.html"},
+	HeaderField{Name: ":scheme", Value: "http"},
+	HeaderField{Name: ":scheme", Value: "https"},
+	HeaderField{Name: ":status", Value: "200"},
+	HeaderField{Name: ":status", Value: "204"},
+	HeaderField{Name: ":status", Value: "206"},
+	HeaderField{Name: ":status", Value: "304"},
+	HeaderField{Name: ":status", Value: "400"},
+	HeaderField{Name: ":status", Value: "404"},
+	HeaderField{Name: ":status", Value: "500"},
+	HeaderField{Name: "accept-charset"},
+	HeaderField{Name: "accept-encoding", Value: "gzip, deflate"},
+	HeaderField{Name: "accept-language"},
+	HeaderField{Name: "accept-ranges"},
+	HeaderField{Name: "accept"},
+	HeaderField{Name: "access-control-allow-origin"},
+	HeaderField{Name: "age"},
+	HeaderField{Name: "allow"},
+	HeaderField{Name: "authorization"},
+	HeaderField{Name: "cache-control"},
+	HeaderField{Name: "content-disposition"},
+	HeaderField{Name: "content-encoding"},
+	HeaderField{Name: "content-language"},
+	HeaderField{Name: "content-length"},
+	HeaderField{Name: "content-location"},
+	HeaderField{Name: "content-range"},
+	HeaderField{Name: "content-type"},
+	HeaderField{Name: "cookie"},
+	HeaderField{Name: "date"},
+	HeaderField{Name: "etag"},
+	HeaderField{Name: "expect"},
+	HeaderField{Name: "expires"},
+	HeaderField{Name: "from"},
+	HeaderField{Name: "host"},
+	HeaderField{Name: "if-match"},
+	HeaderField{Name: "if-modified-since"},
+	HeaderField{Name: "if-none-match"},
+	HeaderField{Name: "if-range"},
+	HeaderField{Name: "if-unmodified-since"},
+	HeaderField{Name: "last-modified"},
+	HeaderField{Name: "link"},
+	HeaderField{Name: "location"},
+	HeaderField{Name: "max-forwards"},
+	HeaderField{Name: "proxy-authenticate"},
+	HeaderField{Name: "proxy-authorization"},
+	HeaderField{Name: "range"},
+	HeaderField{Name: "referer"},
+	HeaderField{Name: "refresh"},
+	HeaderField{Name: "retry-after"},
+	HeaderField{Name: "server"},
+	HeaderField{Name: "set-cookie"},
+	HeaderField{Name: "strict-transport-security"},
+	HeaderField{Name: "transfer-encoding"},
+	HeaderField{Name: "user-agent"},
+	HeaderField{Name: "vary"},
+	HeaderField{Name: "via"},
+	HeaderField{Name: "www-authenticate"},
+}
+
+func newStaticTable() *headerFieldTable {
+	t := &headerFieldTable{}
+	t.init()
+	for _, e := range staticTableEntries[:] {
+		t.addEntry(e)
+	}
+	return t
 }
 
 var huffmanCodes = [256]uint32{
diff --git a/libgo/go/golang_org/x/net/http2/hpack/tables_test.go b/libgo/go/golang_org/x/net/http2/hpack/tables_test.go
new file mode 100644
index 0000000..d963f36
--- /dev/null
+++ b/libgo/go/golang_org/x/net/http2/hpack/tables_test.go
@@ -0,0 +1,214 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package hpack
+
+import (
+	"bufio"
+	"regexp"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+func TestHeaderFieldTable(t *testing.T) {
+	table := &headerFieldTable{}
+	table.init()
+	table.addEntry(pair("key1", "value1-1"))
+	table.addEntry(pair("key2", "value2-1"))
+	table.addEntry(pair("key1", "value1-2"))
+	table.addEntry(pair("key3", "value3-1"))
+	table.addEntry(pair("key4", "value4-1"))
+	table.addEntry(pair("key2", "value2-2"))
+
+	// Tests will be run twice: once before evicting anything, and
+	// again after evicting the three oldest entries.
+	tests := []struct {
+		f                 HeaderField
+		beforeWantStaticI uint64
+		beforeWantMatch   bool
+		afterWantStaticI  uint64
+		afterWantMatch    bool
+	}{
+		{HeaderField{"key1", "value1-1", false}, 1, true, 0, false},
+		{HeaderField{"key1", "value1-2", false}, 3, true, 0, false},
+		{HeaderField{"key1", "value1-3", false}, 3, false, 0, false},
+		{HeaderField{"key2", "value2-1", false}, 2, true, 3, false},
+		{HeaderField{"key2", "value2-2", false}, 6, true, 3, true},
+		{HeaderField{"key2", "value2-3", false}, 6, false, 3, false},
+		{HeaderField{"key4", "value4-1", false}, 5, true, 2, true},
+		// Name match only, because sensitive.
+		{HeaderField{"key4", "value4-1", true}, 5, false, 2, false},
+		// Key not found.
+		{HeaderField{"key5", "value5-x", false}, 0, false, 0, false},
+	}
+
+	staticToDynamic := func(i uint64) uint64 {
+		if i == 0 {
+			return 0
+		}
+		return uint64(table.len()) - i + 1 // dynamic is the reversed table
+	}
+
+	searchStatic := func(f HeaderField) (uint64, bool) {
+		old := staticTable
+		staticTable = table
+		defer func() { staticTable = old }()
+		return staticTable.search(f)
+	}
+
+	searchDynamic := func(f HeaderField) (uint64, bool) {
+		return table.search(f)
+	}
+
+	for _, test := range tests {
+		gotI, gotMatch := searchStatic(test.f)
+		if wantI, wantMatch := test.beforeWantStaticI, test.beforeWantMatch; gotI != wantI || gotMatch != wantMatch {
+			t.Errorf("before evictions: searchStatic(%+v)=%v,%v want %v,%v", test.f, gotI, gotMatch, wantI, wantMatch)
+		}
+		gotI, gotMatch = searchDynamic(test.f)
+		wantDynamicI := staticToDynamic(test.beforeWantStaticI)
+		if wantI, wantMatch := wantDynamicI, test.beforeWantMatch; gotI != wantI || gotMatch != wantMatch {
+			t.Errorf("before evictions: searchDynamic(%+v)=%v,%v want %v,%v", test.f, gotI, gotMatch, wantI, wantMatch)
+		}
+	}
+
+	table.evictOldest(3)
+
+	for _, test := range tests {
+		gotI, gotMatch := searchStatic(test.f)
+		if wantI, wantMatch := test.afterWantStaticI, test.afterWantMatch; gotI != wantI || gotMatch != wantMatch {
+			t.Errorf("after evictions: searchStatic(%+v)=%v,%v want %v,%v", test.f, gotI, gotMatch, wantI, wantMatch)
+		}
+		gotI, gotMatch = searchDynamic(test.f)
+		wantDynamicI := staticToDynamic(test.afterWantStaticI)
+		if wantI, wantMatch := wantDynamicI, test.afterWantMatch; gotI != wantI || gotMatch != wantMatch {
+			t.Errorf("after evictions: searchDynamic(%+v)=%v,%v want %v,%v", test.f, gotI, gotMatch, wantI, wantMatch)
+		}
+	}
+}
+
+func TestHeaderFieldTable_LookupMapEviction(t *testing.T) {
+	table := &headerFieldTable{}
+	table.init()
+	table.addEntry(pair("key1", "value1-1"))
+	table.addEntry(pair("key2", "value2-1"))
+	table.addEntry(pair("key1", "value1-2"))
+	table.addEntry(pair("key3", "value3-1"))
+	table.addEntry(pair("key4", "value4-1"))
+	table.addEntry(pair("key2", "value2-2"))
+
+	// evict all pairs
+	table.evictOldest(table.len())
+
+	if l := table.len(); l > 0 {
+		t.Errorf("table.len() = %d, want 0", l)
+	}
+
+	if l := len(table.byName); l > 0 {
+		t.Errorf("len(table.byName) = %d, want 0", l)
+	}
+
+	if l := len(table.byNameValue); l > 0 {
+		t.Errorf("len(table.byNameValue) = %d, want 0", l)
+	}
+}
+
+func TestStaticTable(t *testing.T) {
+	fromSpec := `
+          +-------+-----------------------------+---------------+
+          | 1     | :authority                  |               |
+          | 2     | :method                     | GET           |
+          | 3     | :method                     | POST          |
+          | 4     | :path                       | /             |
+          | 5     | :path                       | /index.html   |
+          | 6     | :scheme                     | http          |
+          | 7     | :scheme                     | https         |
+          | 8     | :status                     | 200           |
+          | 9     | :status                     | 204           |
+          | 10    | :status                     | 206           |
+          | 11    | :status                     | 304           |
+          | 12    | :status                     | 400           |
+          | 13    | :status                     | 404           |
+          | 14    | :status                     | 500           |
+          | 15    | accept-charset              |               |
+          | 16    | accept-encoding             | gzip, deflate |
+          | 17    | accept-language             |               |
+          | 18    | accept-ranges               |               |
+          | 19    | accept                      |               |
+          | 20    | access-control-allow-origin |               |
+          | 21    | age                         |               |
+          | 22    | allow                       |               |
+          | 23    | authorization               |               |
+          | 24    | cache-control               |               |
+          | 25    | content-disposition         |               |
+          | 26    | content-encoding            |               |
+          | 27    | content-language            |               |
+          | 28    | content-length              |               |
+          | 29    | content-location            |               |
+          | 30    | content-range               |               |
+          | 31    | content-type                |               |
+          | 32    | cookie                      |               |
+          | 33    | date                        |               |
+          | 34    | etag                        |               |
+          | 35    | expect                      |               |
+          | 36    | expires                     |               |
+          | 37    | from                        |               |
+          | 38    | host                        |               |
+          | 39    | if-match                    |               |
+          | 40    | if-modified-since           |               |
+          | 41    | if-none-match               |               |
+          | 42    | if-range                    |               |
+          | 43    | if-unmodified-since         |               |
+          | 44    | last-modified               |               |
+          | 45    | link                        |               |
+          | 46    | location                    |               |
+          | 47    | max-forwards                |               |
+          | 48    | proxy-authenticate          |               |
+          | 49    | proxy-authorization         |               |
+          | 50    | range                       |               |
+          | 51    | referer                     |               |
+          | 52    | refresh                     |               |
+          | 53    | retry-after                 |               |
+          | 54    | server                      |               |
+          | 55    | set-cookie                  |               |
+          | 56    | strict-transport-security   |               |
+          | 57    | transfer-encoding           |               |
+          | 58    | user-agent                  |               |
+          | 59    | vary                        |               |
+          | 60    | via                         |               |
+          | 61    | www-authenticate            |               |
+          +-------+-----------------------------+---------------+
+`
+	bs := bufio.NewScanner(strings.NewReader(fromSpec))
+	re := regexp.MustCompile(`\| (\d+)\s+\| (\S+)\s*\| (\S(.*\S)?)?\s+\|`)
+	for bs.Scan() {
+		l := bs.Text()
+		if !strings.Contains(l, "|") {
+			continue
+		}
+		m := re.FindStringSubmatch(l)
+		if m == nil {
+			continue
+		}
+		i, err := strconv.Atoi(m[1])
+		if err != nil {
+			t.Errorf("Bogus integer on line %q", l)
+			continue
+		}
+		if i < 1 || i > staticTable.len() {
+			t.Errorf("Bogus index %d on line %q", i, l)
+			continue
+		}
+		if got, want := staticTable.ents[i-1].Name, m[2]; got != want {
+			t.Errorf("header index %d name = %q; want %q", i, got, want)
+		}
+		if got, want := staticTable.ents[i-1].Value, m[3]; got != want {
+			t.Errorf("header index %d value = %q; want %q", i, got, want)
+		}
+	}
+	if err := bs.Err(); err != nil {
+		t.Error(err)
+	}
+}
diff --git a/libgo/go/golang_org/x/net/idna/idna.go b/libgo/go/golang_org/x/net/idna/idna.go
index 3daa897..e8307f9 100644
--- a/libgo/go/golang_org/x/net/idna/idna.go
+++ b/libgo/go/golang_org/x/net/idna/idna.go
@@ -1,61 +1,661 @@
-// Copyright 2012 The Go Authors. All rights reserved.
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package idna implements IDNA2008 (Internationalized Domain Names for
-// Applications), defined in RFC 5890, RFC 5891, RFC 5892, RFC 5893 and
-// RFC 5894.
-package idna // import "golang.org/x/net/idna"
+// Package idna implements IDNA2008 using the compatibility processing
+// defined by UTS (Unicode Technical Standard) #46, which defines a standard to
+// deal with the transition from IDNA2003.
+//
+// IDNA2008 (Internationalized Domain Names for Applications), is defined in RFC
+// 5890, RFC 5891, RFC 5892, RFC 5893 and RFC 5894.
+// UTS #46 is defined in http://www.unicode.org/reports/tr46.
+// See http://unicode.org/cldr/utility/idna.jsp for a visualization of the
+// differences between these two standards.
+package idna // import "golang_org/x/text/internal/export/idna"
 
 import (
+	"fmt"
 	"strings"
 	"unicode/utf8"
+
+	"golang_org/x/text/secure/bidirule"
+	"golang_org/x/text/unicode/norm"
 )
 
-// TODO(nigeltao): specify when errors occur. For example, is ToASCII(".") or
-// ToASCII("foo\x00") an error? See also http://www.unicode.org/faq/idn.html#11
+// NOTE: Unlike common practice in Go APIs, the functions will return a
+// sanitized domain name in case of errors. Browsers sometimes use a partially
+// evaluated string as lookup.
+// TODO: the current error handling is, in my opinion, the least opinionated.
+// Other strategies are also viable, though:
+// Option 1) Return an empty string in case of error, but allow the user to
+//    specify explicitly which errors to ignore.
+// Option 2) Return the partially evaluated string if it is itself a valid
+//    string, otherwise return the empty string in case of error.
+// Option 3) Option 1 and 2.
+// Option 4) Always return an empty string for now and implement Option 1 as
+//    needed, and document that the return string may not be empty in case of
+//    error in the future.
+// I think Option 1 is best, but it is quite opinionated.
 
-// acePrefix is the ASCII Compatible Encoding prefix.
-const acePrefix = "xn--"
+// ToASCII is a wrapper for Punycode.ToASCII.
+func ToASCII(s string) (string, error) {
+	return Punycode.process(s, true)
+}
+
+// ToUnicode is a wrapper for Punycode.ToUnicode.
+func ToUnicode(s string) (string, error) {
+	return Punycode.process(s, false)
+}
+
+// An Option configures a Profile at creation time.
+type Option func(*options)
+
+// Transitional sets a Profile to use the Transitional mapping as defined in UTS
+// #46. This will cause, for example, "ß" to be mapped to "ss". Using the
+// transitional mapping provides a compromise between IDNA2003 and IDNA2008
+// compatibility. It is used by most browsers when resolving domain names. This
+// option is only meaningful if combined with MapForLookup.
+func Transitional(transitional bool) Option {
+	return func(o *options) { o.transitional = true }
+}
+
+// VerifyDNSLength sets whether a Profile should fail if any of the IDN parts
+// are longer than allowed by the RFC.
+func VerifyDNSLength(verify bool) Option {
+	return func(o *options) { o.verifyDNSLength = verify }
+}
+
+// ValidateLabels sets whether to check the mandatory label validation criteria
+// as defined in Section 5.4 of RFC 5891. This includes testing for correct use
+// of hyphens ('-'), normalization, validity of runes, and the context rules.
+func ValidateLabels(enable bool) Option {
+	return func(o *options) {
+		// Don't override existing mappings, but set one that at least checks
+		// normalization if it is not set.
+		if o.mapping == nil && enable {
+			o.mapping = normalize
+		}
+		o.trie = trie
+		o.validateLabels = enable
+		o.fromPuny = validateFromPunycode
+	}
+}
+
+// StrictDomainName limits the set of permissable ASCII characters to those
+// allowed in domain names as defined in RFC 1034 (A-Z, a-z, 0-9 and the
+// hyphen). This is set by default for MapForLookup and ValidateForRegistration.
+//
+// This option is useful, for instance, for browsers that allow characters
+// outside this range, for example a '_' (U+005F LOW LINE). See
+// http://www.rfc-editor.org/std/std3.txt for more details This option
+// corresponds to the UseSTD3ASCIIRules option in UTS #46.
+func StrictDomainName(use bool) Option {
+	return func(o *options) {
+		o.trie = trie
+		o.useSTD3Rules = use
+		o.fromPuny = validateFromPunycode
+	}
+}
+
+// NOTE: the following options pull in tables. The tables should not be linked
+// in as long as the options are not used.
+
+// BidiRule enables the Bidi rule as defined in RFC 5893. Any application
+// that relies on proper validation of labels should include this rule.
+func BidiRule() Option {
+	return func(o *options) { o.bidirule = bidirule.ValidString }
+}
+
+// ValidateForRegistration sets validation options to verify that a given IDN is
+// properly formatted for registration as defined by Section 4 of RFC 5891.
+func ValidateForRegistration() Option {
+	return func(o *options) {
+		o.mapping = validateRegistration
+		StrictDomainName(true)(o)
+		ValidateLabels(true)(o)
+		VerifyDNSLength(true)(o)
+		BidiRule()(o)
+	}
+}
+
+// MapForLookup sets validation and mapping options such that a given IDN is
+// transformed for domain name lookup according to the requirements set out in
+// Section 5 of RFC 5891. The mappings follow the recommendations of RFC 5894,
+// RFC 5895 and UTS 46. It does not add the Bidi Rule. Use the BidiRule option
+// to add this check.
+//
+// The mappings include normalization and mapping case, width and other
+// compatibility mappings.
+func MapForLookup() Option {
+	return func(o *options) {
+		o.mapping = validateAndMap
+		StrictDomainName(true)(o)
+		ValidateLabels(true)(o)
+	}
+}
+
+type options struct {
+	transitional    bool
+	useSTD3Rules    bool
+	validateLabels  bool
+	verifyDNSLength bool
+
+	trie *idnaTrie
+
+	// fromPuny calls validation rules when converting A-labels to U-labels.
+	fromPuny func(p *Profile, s string) error
+
+	// mapping implements a validation and mapping step as defined in RFC 5895
+	// or UTS 46, tailored to, for example, domain registration or lookup.
+	mapping func(p *Profile, s string) (string, error)
+
+	// bidirule, if specified, checks whether s conforms to the Bidi Rule
+	// defined in RFC 5893.
+	bidirule func(s string) bool
+}
+
+// A Profile defines the configuration of a IDNA mapper.
+type Profile struct {
+	options
+}
+
+func apply(o *options, opts []Option) {
+	for _, f := range opts {
+		f(o)
+	}
+}
+
+// New creates a new Profile.
+//
+// With no options, the returned Profile is the most permissive and equals the
+// Punycode Profile. Options can be passed to further restrict the Profile. The
+// MapForLookup and ValidateForRegistration options set a collection of options,
+// for lookup and registration purposes respectively, which can be tailored by
+// adding more fine-grained options, where later options override earlier
+// options.
+func New(o ...Option) *Profile {
+	p := &Profile{}
+	apply(&p.options, o)
+	return p
+}
 
 // ToASCII converts a domain or domain label to its ASCII form. For example,
 // ToASCII("bücher.example.com") is "xn--bcher-kva.example.com", and
-// ToASCII("golang") is "golang".
-func ToASCII(s string) (string, error) {
-	if ascii(s) {
-		return s, nil
-	}
-	labels := strings.Split(s, ".")
-	for i, label := range labels {
-		if !ascii(label) {
-			a, err := encode(acePrefix, label)
-			if err != nil {
-				return "", err
-			}
-			labels[i] = a
-		}
-	}
-	return strings.Join(labels, "."), nil
+// ToASCII("golang") is "golang". If an error is encountered it will return
+// an error and a (partially) processed result.
+func (p *Profile) ToASCII(s string) (string, error) {
+	return p.process(s, true)
 }
 
 // ToUnicode converts a domain or domain label to its Unicode form. For example,
 // ToUnicode("xn--bcher-kva.example.com") is "bücher.example.com", and
-// ToUnicode("golang") is "golang".
-func ToUnicode(s string) (string, error) {
-	if !strings.Contains(s, acePrefix) {
-		return s, nil
+// ToUnicode("golang") is "golang". If an error is encountered it will return
+// an error and a (partially) processed result.
+func (p *Profile) ToUnicode(s string) (string, error) {
+	pp := *p
+	pp.transitional = false
+	return pp.process(s, false)
+}
+
+// String reports a string with a description of the profile for debugging
+// purposes. The string format may change with different versions.
+func (p *Profile) String() string {
+	s := ""
+	if p.transitional {
+		s = "Transitional"
+	} else {
+		s = "NonTransitional"
 	}
-	labels := strings.Split(s, ".")
-	for i, label := range labels {
-		if strings.HasPrefix(label, acePrefix) {
-			u, err := decode(label[len(acePrefix):])
-			if err != nil {
-				return "", err
+	if p.useSTD3Rules {
+		s += ":UseSTD3Rules"
+	}
+	if p.validateLabels {
+		s += ":ValidateLabels"
+	}
+	if p.verifyDNSLength {
+		s += ":VerifyDNSLength"
+	}
+	return s
+}
+
+var (
+	// Punycode is a Profile that does raw punycode processing with a minimum
+	// of validation.
+	Punycode *Profile = punycode
+
+	// Lookup is the recommended profile for looking up domain names, according
+	// to Section 5 of RFC 5891. The exact configuration of this profile may
+	// change over time.
+	Lookup *Profile = lookup
+
+	// Display is the recommended profile for displaying domain names.
+	// The configuration of this profile may change over time.
+	Display *Profile = display
+
+	// Registration is the recommended profile for checking whether a given
+	// IDN is valid for registration, according to Section 4 of RFC 5891.
+	Registration *Profile = registration
+
+	punycode = &Profile{}
+	lookup   = &Profile{options{
+		transitional:   true,
+		useSTD3Rules:   true,
+		validateLabels: true,
+		trie:           trie,
+		fromPuny:       validateFromPunycode,
+		mapping:        validateAndMap,
+		bidirule:       bidirule.ValidString,
+	}}
+	display = &Profile{options{
+		useSTD3Rules:   true,
+		validateLabels: true,
+		trie:           trie,
+		fromPuny:       validateFromPunycode,
+		mapping:        validateAndMap,
+		bidirule:       bidirule.ValidString,
+	}}
+	registration = &Profile{options{
+		useSTD3Rules:    true,
+		validateLabels:  true,
+		verifyDNSLength: true,
+		trie:            trie,
+		fromPuny:        validateFromPunycode,
+		mapping:         validateRegistration,
+		bidirule:        bidirule.ValidString,
+	}}
+
+	// TODO: profiles
+	// Register: recommended for approving domain names: don't do any mappings
+	// but rather reject on invalid input. Bundle or block deviation characters.
+)
+
+type labelError struct{ label, code_ string }
+
+func (e labelError) code() string { return e.code_ }
+func (e labelError) Error() string {
+	return fmt.Sprintf("idna: invalid label %q", e.label)
+}
+
+type runeError rune
+
+func (e runeError) code() string { return "P1" }
+func (e runeError) Error() string {
+	return fmt.Sprintf("idna: disallowed rune %U", e)
+}
+
+// process implements the algorithm described in section 4 of UTS #46,
+// see http://www.unicode.org/reports/tr46.
+func (p *Profile) process(s string, toASCII bool) (string, error) {
+	var err error
+	if p.mapping != nil {
+		s, err = p.mapping(p, s)
+	}
+	// Remove leading empty labels.
+	for ; len(s) > 0 && s[0] == '.'; s = s[1:] {
+	}
+	// It seems like we should only create this error on ToASCII, but the
+	// UTS 46 conformance tests suggests we should always check this.
+	if err == nil && p.verifyDNSLength && s == "" {
+		err = &labelError{s, "A4"}
+	}
+	labels := labelIter{orig: s}
+	for ; !labels.done(); labels.next() {
+		label := labels.label()
+		if label == "" {
+			// Empty labels are not okay. The label iterator skips the last
+			// label if it is empty.
+			if err == nil && p.verifyDNSLength {
+				err = &labelError{s, "A4"}
 			}
-			labels[i] = u
+			continue
+		}
+		if strings.HasPrefix(label, acePrefix) {
+			u, err2 := decode(label[len(acePrefix):])
+			if err2 != nil {
+				if err == nil {
+					err = err2
+				}
+				// Spec says keep the old label.
+				continue
+			}
+			labels.set(u)
+			if err == nil && p.validateLabels {
+				err = p.fromPuny(p, u)
+			}
+			if err == nil {
+				// This should be called on NonTransitional, according to the
+				// spec, but that currently does not have any effect. Use the
+				// original profile to preserve options.
+				err = p.validateLabel(u)
+			}
+		} else if err == nil {
+			err = p.validateLabel(label)
 		}
 	}
-	return strings.Join(labels, "."), nil
+	if toASCII {
+		for labels.reset(); !labels.done(); labels.next() {
+			label := labels.label()
+			if !ascii(label) {
+				a, err2 := encode(acePrefix, label)
+				if err == nil {
+					err = err2
+				}
+				label = a
+				labels.set(a)
+			}
+			n := len(label)
+			if p.verifyDNSLength && err == nil && (n == 0 || n > 63) {
+				err = &labelError{label, "A4"}
+			}
+		}
+	}
+	s = labels.result()
+	if toASCII && p.verifyDNSLength && err == nil {
+		// Compute the length of the domain name minus the root label and its dot.
+		n := len(s)
+		if n > 0 && s[n-1] == '.' {
+			n--
+		}
+		if len(s) < 1 || n > 253 {
+			err = &labelError{s, "A4"}
+		}
+	}
+	return s, err
+}
+
+func normalize(p *Profile, s string) (string, error) {
+	return norm.NFC.String(s), nil
+}
+
+func validateRegistration(p *Profile, s string) (string, error) {
+	if !norm.NFC.IsNormalString(s) {
+		return s, &labelError{s, "V1"}
+	}
+	var err error
+	for i := 0; i < len(s); {
+		v, sz := trie.lookupString(s[i:])
+		i += sz
+		// Copy bytes not copied so far.
+		switch p.simplify(info(v).category()) {
+		// TODO: handle the NV8 defined in the Unicode idna data set to allow
+		// for strict conformance to IDNA2008.
+		case valid, deviation:
+		case disallowed, mapped, unknown, ignored:
+			if err == nil {
+				r, _ := utf8.DecodeRuneInString(s[i:])
+				err = runeError(r)
+			}
+		}
+	}
+	return s, err
+}
+
+func validateAndMap(p *Profile, s string) (string, error) {
+	var (
+		err error
+		b   []byte
+		k   int
+	)
+	for i := 0; i < len(s); {
+		v, sz := trie.lookupString(s[i:])
+		start := i
+		i += sz
+		// Copy bytes not copied so far.
+		switch p.simplify(info(v).category()) {
+		case valid:
+			continue
+		case disallowed:
+			if err == nil {
+				r, _ := utf8.DecodeRuneInString(s[i:])
+				err = runeError(r)
+			}
+			continue
+		case mapped, deviation:
+			b = append(b, s[k:start]...)
+			b = info(v).appendMapping(b, s[start:i])
+		case ignored:
+			b = append(b, s[k:start]...)
+			// drop the rune
+		case unknown:
+			b = append(b, s[k:start]...)
+			b = append(b, "\ufffd"...)
+		}
+		k = i
+	}
+	if k == 0 {
+		// No changes so far.
+		s = norm.NFC.String(s)
+	} else {
+		b = append(b, s[k:]...)
+		if norm.NFC.QuickSpan(b) != len(b) {
+			b = norm.NFC.Bytes(b)
+		}
+		// TODO: the punycode converters require strings as input.
+		s = string(b)
+	}
+	return s, err
+}
+
+// A labelIter allows iterating over domain name labels.
+type labelIter struct {
+	orig     string
+	slice    []string
+	curStart int
+	curEnd   int
+	i        int
+}
+
+func (l *labelIter) reset() {
+	l.curStart = 0
+	l.curEnd = 0
+	l.i = 0
+}
+
+func (l *labelIter) done() bool {
+	return l.curStart >= len(l.orig)
+}
+
+func (l *labelIter) result() string {
+	if l.slice != nil {
+		return strings.Join(l.slice, ".")
+	}
+	return l.orig
+}
+
+func (l *labelIter) label() string {
+	if l.slice != nil {
+		return l.slice[l.i]
+	}
+	p := strings.IndexByte(l.orig[l.curStart:], '.')
+	l.curEnd = l.curStart + p
+	if p == -1 {
+		l.curEnd = len(l.orig)
+	}
+	return l.orig[l.curStart:l.curEnd]
+}
+
+// next sets the value to the next label. It skips the last label if it is empty.
+func (l *labelIter) next() {
+	l.i++
+	if l.slice != nil {
+		if l.i >= len(l.slice) || l.i == len(l.slice)-1 && l.slice[l.i] == "" {
+			l.curStart = len(l.orig)
+		}
+	} else {
+		l.curStart = l.curEnd + 1
+		if l.curStart == len(l.orig)-1 && l.orig[l.curStart] == '.' {
+			l.curStart = len(l.orig)
+		}
+	}
+}
+
+func (l *labelIter) set(s string) {
+	if l.slice == nil {
+		l.slice = strings.Split(l.orig, ".")
+	}
+	l.slice[l.i] = s
+}
+
+// acePrefix is the ASCII Compatible Encoding prefix.
+const acePrefix = "xn--"
+
+func (p *Profile) simplify(cat category) category {
+	switch cat {
+	case disallowedSTD3Mapped:
+		if p.useSTD3Rules {
+			cat = disallowed
+		} else {
+			cat = mapped
+		}
+	case disallowedSTD3Valid:
+		if p.useSTD3Rules {
+			cat = disallowed
+		} else {
+			cat = valid
+		}
+	case deviation:
+		if !p.transitional {
+			cat = valid
+		}
+	case validNV8, validXV8:
+		// TODO: handle V2008
+		cat = valid
+	}
+	return cat
+}
+
+func validateFromPunycode(p *Profile, s string) error {
+	if !norm.NFC.IsNormalString(s) {
+		return &labelError{s, "V1"}
+	}
+	for i := 0; i < len(s); {
+		v, sz := trie.lookupString(s[i:])
+		if c := p.simplify(info(v).category()); c != valid && c != deviation {
+			return &labelError{s, "V6"}
+		}
+		i += sz
+	}
+	return nil
+}
+
+const (
+	zwnj = "\u200c"
+	zwj  = "\u200d"
+)
+
+type joinState int8
+
+const (
+	stateStart joinState = iota
+	stateVirama
+	stateBefore
+	stateBeforeVirama
+	stateAfter
+	stateFAIL
+)
+
+var joinStates = [][numJoinTypes]joinState{
+	stateStart: {
+		joiningL:   stateBefore,
+		joiningD:   stateBefore,
+		joinZWNJ:   stateFAIL,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateVirama,
+	},
+	stateVirama: {
+		joiningL: stateBefore,
+		joiningD: stateBefore,
+	},
+	stateBefore: {
+		joiningL:   stateBefore,
+		joiningD:   stateBefore,
+		joiningT:   stateBefore,
+		joinZWNJ:   stateAfter,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateBeforeVirama,
+	},
+	stateBeforeVirama: {
+		joiningL: stateBefore,
+		joiningD: stateBefore,
+		joiningT: stateBefore,
+	},
+	stateAfter: {
+		joiningL:   stateFAIL,
+		joiningD:   stateBefore,
+		joiningT:   stateAfter,
+		joiningR:   stateStart,
+		joinZWNJ:   stateFAIL,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateAfter, // no-op as we can't accept joiners here
+	},
+	stateFAIL: {
+		0:          stateFAIL,
+		joiningL:   stateFAIL,
+		joiningD:   stateFAIL,
+		joiningT:   stateFAIL,
+		joiningR:   stateFAIL,
+		joinZWNJ:   stateFAIL,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateFAIL,
+	},
+}
+
+// validateLabel validates the criteria from Section 4.1. Item 1, 4, and 6 are
+// already implicitly satisfied by the overall implementation.
+func (p *Profile) validateLabel(s string) error {
+	if s == "" {
+		if p.verifyDNSLength {
+			return &labelError{s, "A4"}
+		}
+		return nil
+	}
+	if p.bidirule != nil && !p.bidirule(s) {
+		return &labelError{s, "B"}
+	}
+	if !p.validateLabels {
+		return nil
+	}
+	trie := p.trie // p.validateLabels is only set if trie is set.
+	if len(s) > 4 && s[2] == '-' && s[3] == '-' {
+		return &labelError{s, "V2"}
+	}
+	if s[0] == '-' || s[len(s)-1] == '-' {
+		return &labelError{s, "V3"}
+	}
+	// TODO: merge the use of this in the trie.
+	v, sz := trie.lookupString(s)
+	x := info(v)
+	if x.isModifier() {
+		return &labelError{s, "V5"}
+	}
+	// Quickly return in the absence of zero-width (non) joiners.
+	if strings.Index(s, zwj) == -1 && strings.Index(s, zwnj) == -1 {
+		return nil
+	}
+	st := stateStart
+	for i := 0; ; {
+		jt := x.joinType()
+		if s[i:i+sz] == zwj {
+			jt = joinZWJ
+		} else if s[i:i+sz] == zwnj {
+			jt = joinZWNJ
+		}
+		st = joinStates[st][jt]
+		if x.isViramaModifier() {
+			st = joinStates[st][joinVirama]
+		}
+		if i += sz; i == len(s) {
+			break
+		}
+		v, sz = trie.lookupString(s[i:])
+		x = info(v)
+	}
+	if st == stateFAIL || st == stateAfter {
+		return &labelError{s, "C"}
+	}
+	return nil
 }
 
 func ascii(s string) bool {
diff --git a/libgo/go/golang_org/x/net/idna/punycode.go b/libgo/go/golang_org/x/net/idna/punycode.go
index 92e733f..fab9229 100644
--- a/libgo/go/golang_org/x/net/idna/punycode.go
+++ b/libgo/go/golang_org/x/net/idna/punycode.go
@@ -1,4 +1,6 @@
-// Copyright 2012 The Go Authors. All rights reserved.
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
@@ -7,7 +9,6 @@
 // This file implements the Punycode algorithm from RFC 3492.
 
 import (
-	"fmt"
 	"math"
 	"strings"
 	"unicode/utf8"
@@ -27,6 +28,8 @@
 	tmin        int32 = 1
 )
 
+func punyError(s string) error { return &labelError{s, "A3"} }
+
 // decode decodes a string as specified in section 6.2.
 func decode(encoded string) (string, error) {
 	if encoded == "" {
@@ -34,7 +37,7 @@
 	}
 	pos := 1 + strings.LastIndex(encoded, "-")
 	if pos == 1 {
-		return "", fmt.Errorf("idna: invalid label %q", encoded)
+		return "", punyError(encoded)
 	}
 	if pos == len(encoded) {
 		return encoded[:len(encoded)-1], nil
@@ -50,16 +53,16 @@
 		oldI, w := i, int32(1)
 		for k := base; ; k += base {
 			if pos == len(encoded) {
-				return "", fmt.Errorf("idna: invalid label %q", encoded)
+				return "", punyError(encoded)
 			}
 			digit, ok := decodeDigit(encoded[pos])
 			if !ok {
-				return "", fmt.Errorf("idna: invalid label %q", encoded)
+				return "", punyError(encoded)
 			}
 			pos++
 			i += digit * w
 			if i < 0 {
-				return "", fmt.Errorf("idna: invalid label %q", encoded)
+				return "", punyError(encoded)
 			}
 			t := k - bias
 			if t < tmin {
@@ -72,7 +75,7 @@
 			}
 			w *= base - t
 			if w >= math.MaxInt32/base {
-				return "", fmt.Errorf("idna: invalid label %q", encoded)
+				return "", punyError(encoded)
 			}
 		}
 		x := int32(len(output) + 1)
@@ -80,7 +83,7 @@
 		n += i / x
 		i %= x
 		if n > utf8.MaxRune || len(output) >= 1024 {
-			return "", fmt.Errorf("idna: invalid label %q", encoded)
+			return "", punyError(encoded)
 		}
 		output = append(output, 0)
 		copy(output[i+1:], output[i:])
@@ -121,14 +124,14 @@
 		}
 		delta += (m - n) * (h + 1)
 		if delta < 0 {
-			return "", fmt.Errorf("idna: invalid label %q", s)
+			return "", punyError(s)
 		}
 		n = m
 		for _, r := range s {
 			if r < n {
 				delta++
 				if delta < 0 {
-					return "", fmt.Errorf("idna: invalid label %q", s)
+					return "", punyError(s)
 				}
 				continue
 			}
diff --git a/libgo/go/golang_org/x/net/idna/tables.go b/libgo/go/golang_org/x/net/idna/tables.go
new file mode 100644
index 0000000..d57a3e2
--- /dev/null
+++ b/libgo/go/golang_org/x/net/idna/tables.go
@@ -0,0 +1,4479 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Code generated by running "go generate" in golang_org/x/text. DO NOT EDIT.
+
+package idna
+
+// UnicodeVersion is the Unicode version from which the tables in this package are derived.
+const UnicodeVersion = "9.0.0"
+
+var mappings string = "" + // Size: 8176 bytes
+	"\x00\x01 \x03 ̈\x01a\x03 ̄\x012\x013\x03 ́\x03 ̧\x011\x01o\x051⁄4\x051⁄2" +
+	"\x053⁄4\x03i̇\x03l·\x03ʼn\x01s\x03dž\x03ⱥ\x03ⱦ\x01h\x01j\x01r\x01w\x01y" +
+	"\x03 ̆\x03 ̇\x03 ̊\x03 ̨\x03 ̃\x03 ̋\x01l\x01x\x04̈́\x03 ι\x01;\x05 ̈́" +
+	"\x04եւ\x04اٴ\x04وٴ\x04ۇٴ\x04يٴ\x06क़\x06ख़\x06ग़\x06ज़\x06ड़\x06ढ़\x06फ़" +
+	"\x06य़\x06ড়\x06ঢ়\x06য়\x06ਲ਼\x06ਸ਼\x06ਖ਼\x06ਗ਼\x06ਜ਼\x06ਫ਼\x06ଡ଼\x06ଢ଼" +
+	"\x06ํา\x06ໍາ\x06ຫນ\x06ຫມ\x06གྷ\x06ཌྷ\x06དྷ\x06བྷ\x06ཛྷ\x06ཀྵ\x06ཱི\x06ཱུ" +
+	"\x06ྲྀ\x09ྲཱྀ\x06ླྀ\x09ླཱྀ\x06ཱྀ\x06ྒྷ\x06ྜྷ\x06ྡྷ\x06ྦྷ\x06ྫྷ\x06ྐྵ\x02" +
+	"в\x02д\x02о\x02с\x02т\x02ъ\x02ѣ\x02æ\x01b\x01d\x01e\x02ǝ\x01g\x01i\x01k" +
+	"\x01m\x01n\x02ȣ\x01p\x01t\x01u\x02ɐ\x02ɑ\x02ə\x02ɛ\x02ɜ\x02ŋ\x02ɔ\x02ɯ" +
+	"\x01v\x02β\x02γ\x02δ\x02φ\x02χ\x02ρ\x02н\x02ɒ\x01c\x02ɕ\x02ð\x01f\x02ɟ" +
+	"\x02ɡ\x02ɥ\x02ɨ\x02ɩ\x02ɪ\x02ʝ\x02ɭ\x02ʟ\x02ɱ\x02ɰ\x02ɲ\x02ɳ\x02ɴ\x02ɵ" +
+	"\x02ɸ\x02ʂ\x02ʃ\x02ƫ\x02ʉ\x02ʊ\x02ʋ\x02ʌ\x01z\x02ʐ\x02ʑ\x02ʒ\x02θ\x02ss" +
+	"\x02ά\x02έ\x02ή\x02ί\x02ό\x02ύ\x02ώ\x05ἀι\x05ἁι\x05ἂι\x05ἃι\x05ἄι\x05ἅι" +
+	"\x05ἆι\x05ἇι\x05ἠι\x05ἡι\x05ἢι\x05ἣι\x05ἤι\x05ἥι\x05ἦι\x05ἧι\x05ὠι\x05ὡι" +
+	"\x05ὢι\x05ὣι\x05ὤι\x05ὥι\x05ὦι\x05ὧι\x05ὰι\x04αι\x04άι\x05ᾶι\x02ι\x05 ̈͂" +
+	"\x05ὴι\x04ηι\x04ήι\x05ῆι\x05 ̓̀\x05 ̓́\x05 ̓͂\x02ΐ\x05 ̔̀\x05 ̔́\x05 ̔͂" +
+	"\x02ΰ\x05 ̈̀\x01`\x05ὼι\x04ωι\x04ώι\x05ῶι\x06′′\x09′′′\x06‵‵\x09‵‵‵\x02!" +
+	"!\x02??\x02?!\x02!?\x0c′′′′\x010\x014\x015\x016\x017\x018\x019\x01+\x01=" +
+	"\x01(\x01)\x02rs\x02ħ\x02no\x01q\x02sm\x02tm\x02ω\x02å\x02א\x02ב\x02ג" +
+	"\x02ד\x02π\x051⁄7\x051⁄9\x061⁄10\x051⁄3\x052⁄3\x051⁄5\x052⁄5\x053⁄5\x054" +
+	"⁄5\x051⁄6\x055⁄6\x051⁄8\x053⁄8\x055⁄8\x057⁄8\x041⁄\x02ii\x02iv\x02vi" +
+	"\x04viii\x02ix\x02xi\x050⁄3\x06∫∫\x09∫∫∫\x06∮∮\x09∮∮∮\x0210\x0211\x0212" +
+	"\x0213\x0214\x0215\x0216\x0217\x0218\x0219\x0220\x04(10)\x04(11)\x04(12)" +
+	"\x04(13)\x04(14)\x04(15)\x04(16)\x04(17)\x04(18)\x04(19)\x04(20)\x0c∫∫∫∫" +
+	"\x02==\x05⫝̸\x02ɫ\x02ɽ\x02ȿ\x02ɀ\x01.\x04 ゙\x04 ゚\x06より\x06コト\x05(ᄀ)\x05" +
+	"(ᄂ)\x05(ᄃ)\x05(ᄅ)\x05(ᄆ)\x05(ᄇ)\x05(ᄉ)\x05(ᄋ)\x05(ᄌ)\x05(ᄎ)\x05(ᄏ)\x05(ᄐ" +
+	")\x05(ᄑ)\x05(ᄒ)\x05(가)\x05(나)\x05(다)\x05(라)\x05(마)\x05(바)\x05(사)\x05(아)" +
+	"\x05(자)\x05(차)\x05(카)\x05(타)\x05(파)\x05(하)\x05(주)\x08(오전)\x08(오후)\x05(一)" +
+	"\x05(二)\x05(三)\x05(四)\x05(五)\x05(六)\x05(七)\x05(八)\x05(九)\x05(十)\x05(月)" +
+	"\x05(火)\x05(水)\x05(木)\x05(金)\x05(土)\x05(日)\x05(株)\x05(有)\x05(社)\x05(名)" +
+	"\x05(特)\x05(財)\x05(祝)\x05(労)\x05(代)\x05(呼)\x05(学)\x05(監)\x05(企)\x05(資)" +
+	"\x05(協)\x05(祭)\x05(休)\x05(自)\x05(至)\x0221\x0222\x0223\x0224\x0225\x0226" +
+	"\x0227\x0228\x0229\x0230\x0231\x0232\x0233\x0234\x0235\x06참고\x06주의\x0236" +
+	"\x0237\x0238\x0239\x0240\x0241\x0242\x0243\x0244\x0245\x0246\x0247\x0248" +
+	"\x0249\x0250\x041月\x042月\x043月\x044月\x045月\x046月\x047月\x048月\x049月\x0510" +
+	"月\x0511月\x0512月\x02hg\x02ev\x0cアパート\x0cアルファ\x0cアンペア\x09アール\x0cイニング\x09" +
+	"インチ\x09ウォン\x0fエスクード\x0cエーカー\x09オンス\x09オーム\x09カイリ\x0cカラット\x0cカロリー\x09ガロ" +
+	"ン\x09ガンマ\x06ギガ\x09ギニー\x0cキュリー\x0cギルダー\x06キロ\x0fキログラム\x12キロメートル\x0fキロワッ" +
+	"ト\x09グラム\x0fグラムトン\x0fクルゼイロ\x0cクローネ\x09ケース\x09コルナ\x09コーポ\x0cサイクル\x0fサンチ" +
+	"ーム\x0cシリング\x09センチ\x09セント\x09ダース\x06デシ\x06ドル\x06トン\x06ナノ\x09ノット\x09ハイツ" +
+	"\x0fパーセント\x09パーツ\x0cバーレル\x0fピアストル\x09ピクル\x06ピコ\x06ビル\x0fファラッド\x0cフィート" +
+	"\x0fブッシェル\x09フラン\x0fヘクタール\x06ペソ\x09ペニヒ\x09ヘルツ\x09ペンス\x09ページ\x09ベータ\x0cポイ" +
+	"ント\x09ボルト\x06ホン\x09ポンド\x09ホール\x09ホーン\x0cマイクロ\x09マイル\x09マッハ\x09マルク\x0fマ" +
+	"ンション\x0cミクロン\x06ミリ\x0fミリバール\x06メガ\x0cメガトン\x0cメートル\x09ヤード\x09ヤール\x09ユアン" +
+	"\x0cリットル\x06リラ\x09ルピー\x0cルーブル\x06レム\x0fレントゲン\x09ワット\x040点\x041点\x042点" +
+	"\x043点\x044点\x045点\x046点\x047点\x048点\x049点\x0510点\x0511点\x0512点\x0513点" +
+	"\x0514点\x0515点\x0516点\x0517点\x0518点\x0519点\x0520点\x0521点\x0522点\x0523点" +
+	"\x0524点\x02da\x02au\x02ov\x02pc\x02dm\x02iu\x06平成\x06昭和\x06大正\x06明治\x0c株" +
+	"式会社\x02pa\x02na\x02ma\x02ka\x02kb\x02mb\x02gb\x04kcal\x02pf\x02nf\x02m" +
+	"g\x02kg\x02hz\x02ml\x02dl\x02kl\x02fm\x02nm\x02mm\x02cm\x02km\x02m2\x02m" +
+	"3\x05m∕s\x06m∕s2\x07rad∕s\x08rad∕s2\x02ps\x02ns\x02ms\x02pv\x02nv\x02mv" +
+	"\x02kv\x02pw\x02nw\x02mw\x02kw\x02bq\x02cc\x02cd\x06c∕kg\x02db\x02gy\x02" +
+	"ha\x02hp\x02in\x02kk\x02kt\x02lm\x02ln\x02lx\x02ph\x02pr\x02sr\x02sv\x02" +
+	"wb\x05v∕m\x05a∕m\x041日\x042日\x043日\x044日\x045日\x046日\x047日\x048日\x049日" +
+	"\x0510日\x0511日\x0512日\x0513日\x0514日\x0515日\x0516日\x0517日\x0518日\x0519日" +
+	"\x0520日\x0521日\x0522日\x0523日\x0524日\x0525日\x0526日\x0527日\x0528日\x0529日" +
+	"\x0530日\x0531日\x02ь\x02ɦ\x02ɬ\x02ʞ\x02ʇ\x02œ\x04𤋮\x04𢡊\x04𢡄\x04𣏕\x04𥉉" +
+	"\x04𥳐\x04𧻓\x02ff\x02fi\x02fl\x02st\x04մն\x04մե\x04մի\x04վն\x04մխ\x04יִ" +
+	"\x04ײַ\x02ע\x02ה\x02כ\x02ל\x02ם\x02ר\x02ת\x04שׁ\x04שׂ\x06שּׁ\x06שּׂ\x04א" +
+	"ַ\x04אָ\x04אּ\x04בּ\x04גּ\x04דּ\x04הּ\x04וּ\x04זּ\x04טּ\x04יּ\x04ךּ\x04" +
+	"כּ\x04לּ\x04מּ\x04נּ\x04סּ\x04ףּ\x04פּ\x04צּ\x04קּ\x04רּ\x04שּ\x04תּ" +
+	"\x04וֹ\x04בֿ\x04כֿ\x04פֿ\x04אל\x02ٱ\x02ٻ\x02پ\x02ڀ\x02ٺ\x02ٿ\x02ٹ\x02ڤ" +
+	"\x02ڦ\x02ڄ\x02ڃ\x02چ\x02ڇ\x02ڍ\x02ڌ\x02ڎ\x02ڈ\x02ژ\x02ڑ\x02ک\x02گ\x02ڳ" +
+	"\x02ڱ\x02ں\x02ڻ\x02ۀ\x02ہ\x02ھ\x02ے\x02ۓ\x02ڭ\x02ۇ\x02ۆ\x02ۈ\x02ۋ\x02ۅ" +
+	"\x02ۉ\x02ې\x02ى\x04ئا\x04ئە\x04ئو\x04ئۇ\x04ئۆ\x04ئۈ\x04ئې\x04ئى\x02ی\x04" +
+	"ئج\x04ئح\x04ئم\x04ئي\x04بج\x04بح\x04بخ\x04بم\x04بى\x04بي\x04تج\x04تح" +
+	"\x04تخ\x04تم\x04تى\x04تي\x04ثج\x04ثم\x04ثى\x04ثي\x04جح\x04جم\x04حج\x04حم" +
+	"\x04خج\x04خح\x04خم\x04سج\x04سح\x04سخ\x04سم\x04صح\x04صم\x04ضج\x04ضح\x04ضخ" +
+	"\x04ضم\x04طح\x04طم\x04ظم\x04عج\x04عم\x04غج\x04غم\x04فج\x04فح\x04فخ\x04فم" +
+	"\x04فى\x04في\x04قح\x04قم\x04قى\x04قي\x04كا\x04كج\x04كح\x04كخ\x04كل\x04كم" +
+	"\x04كى\x04كي\x04لج\x04لح\x04لخ\x04لم\x04لى\x04لي\x04مج\x04مح\x04مخ\x04مم" +
+	"\x04مى\x04مي\x04نج\x04نح\x04نخ\x04نم\x04نى\x04ني\x04هج\x04هم\x04هى\x04هي" +
+	"\x04يج\x04يح\x04يخ\x04يم\x04يى\x04يي\x04ذٰ\x04رٰ\x04ىٰ\x05 ٌّ\x05 ٍّ\x05" +
+	" َّ\x05 ُّ\x05 ِّ\x05 ّٰ\x04ئر\x04ئز\x04ئن\x04بر\x04بز\x04بن\x04تر\x04تز" +
+	"\x04تن\x04ثر\x04ثز\x04ثن\x04ما\x04نر\x04نز\x04نن\x04ير\x04يز\x04ين\x04ئخ" +
+	"\x04ئه\x04به\x04ته\x04صخ\x04له\x04نه\x04هٰ\x04يه\x04ثه\x04سه\x04شم\x04شه" +
+	"\x06ـَّ\x06ـُّ\x06ـِّ\x04طى\x04طي\x04عى\x04عي\x04غى\x04غي\x04سى\x04سي" +
+	"\x04شى\x04شي\x04حى\x04حي\x04جى\x04جي\x04خى\x04خي\x04صى\x04صي\x04ضى\x04ضي" +
+	"\x04شج\x04شح\x04شخ\x04شر\x04سر\x04صر\x04ضر\x04اً\x06تجم\x06تحج\x06تحم" +
+	"\x06تخم\x06تمج\x06تمح\x06تمخ\x06جمح\x06حمي\x06حمى\x06سحج\x06سجح\x06سجى" +
+	"\x06سمح\x06سمج\x06سمم\x06صحح\x06صمم\x06شحم\x06شجي\x06شمخ\x06شمم\x06ضحى" +
+	"\x06ضخم\x06طمح\x06طمم\x06طمي\x06عجم\x06عمم\x06عمى\x06غمم\x06غمي\x06غمى" +
+	"\x06فخم\x06قمح\x06قمم\x06لحم\x06لحي\x06لحى\x06لجج\x06لخم\x06لمح\x06محج" +
+	"\x06محم\x06محي\x06مجح\x06مجم\x06مخج\x06مخم\x06مجخ\x06همج\x06همم\x06نحم" +
+	"\x06نحى\x06نجم\x06نجى\x06نمي\x06نمى\x06يمم\x06بخي\x06تجي\x06تجى\x06تخي" +
+	"\x06تخى\x06تمي\x06تمى\x06جمي\x06جحى\x06جمى\x06سخى\x06صحي\x06شحي\x06ضحي" +
+	"\x06لجي\x06لمي\x06يحي\x06يجي\x06يمي\x06ممي\x06قمي\x06نحي\x06عمي\x06كمي" +
+	"\x06نجح\x06مخي\x06لجم\x06كمم\x06جحي\x06حجي\x06مجي\x06فمي\x06بحي\x06سخي" +
+	"\x06نجي\x06صلے\x06قلے\x08الله\x08اكبر\x08محمد\x08صلعم\x08رسول\x08عليه" +
+	"\x08وسلم\x06صلى!صلى الله عليه وسلم\x0fجل جلاله\x08ریال\x01,\x01:\x01!" +
+	"\x01?\x01_\x01{\x01}\x01[\x01]\x01#\x01&\x01*\x01-\x01<\x01>\x01\\\x01$" +
+	"\x01%\x01@\x04ـً\x04ـَ\x04ـُ\x04ـِ\x04ـّ\x04ـْ\x02ء\x02آ\x02أ\x02ؤ\x02إ" +
+	"\x02ئ\x02ا\x02ب\x02ة\x02ت\x02ث\x02ج\x02ح\x02خ\x02د\x02ذ\x02ر\x02ز\x02س" +
+	"\x02ش\x02ص\x02ض\x02ط\x02ظ\x02ع\x02غ\x02ف\x02ق\x02ك\x02ل\x02م\x02ن\x02ه" +
+	"\x02و\x02ي\x04لآ\x04لأ\x04لإ\x04لا\x01\x22\x01'\x01/\x01^\x01|\x01~\x02¢" +
+	"\x02£\x02¬\x02¦\x02¥\x08𝅗𝅥\x08𝅘𝅥\x0c𝅘𝅥𝅮\x0c𝅘𝅥𝅯\x0c𝅘𝅥𝅰\x0c𝅘𝅥𝅱\x0c𝅘𝅥𝅲\x08𝆹" +
+	"𝅥\x08𝆺𝅥\x0c𝆹𝅥𝅮\x0c𝆺𝅥𝅮\x0c𝆹𝅥𝅯\x0c𝆺𝅥𝅯\x02ı\x02ȷ\x02α\x02ε\x02ζ\x02η\x02" +
+	"κ\x02λ\x02μ\x02ν\x02ξ\x02ο\x02σ\x02τ\x02υ\x02ψ\x03∇\x03∂\x02ϝ\x02ٮ\x02ڡ" +
+	"\x02ٯ\x020,\x021,\x022,\x023,\x024,\x025,\x026,\x027,\x028,\x029,\x03(a)" +
+	"\x03(b)\x03(c)\x03(d)\x03(e)\x03(f)\x03(g)\x03(h)\x03(i)\x03(j)\x03(k)" +
+	"\x03(l)\x03(m)\x03(n)\x03(o)\x03(p)\x03(q)\x03(r)\x03(s)\x03(t)\x03(u)" +
+	"\x03(v)\x03(w)\x03(x)\x03(y)\x03(z)\x07〔s〕\x02wz\x02hv\x02sd\x03ppv\x02w" +
+	"c\x02mc\x02md\x02dj\x06ほか\x06ココ\x03サ\x03手\x03字\x03双\x03デ\x03二\x03多\x03解" +
+	"\x03天\x03交\x03映\x03無\x03料\x03前\x03後\x03再\x03新\x03初\x03終\x03生\x03販\x03声" +
+	"\x03吹\x03演\x03投\x03捕\x03一\x03三\x03遊\x03左\x03中\x03右\x03指\x03走\x03打\x03禁" +
+	"\x03空\x03合\x03満\x03有\x03月\x03申\x03割\x03営\x03配\x09〔本〕\x09〔三〕\x09〔二〕\x09〔安" +
+	"〕\x09〔点〕\x09〔打〕\x09〔盗〕\x09〔勝〕\x09〔敗〕\x03得\x03可\x03丽\x03丸\x03乁\x03你\x03" +
+	"侮\x03侻\x03倂\x03偺\x03備\x03僧\x03像\x03㒞\x03免\x03兔\x03兤\x03具\x03㒹\x03內\x03" +
+	"冗\x03冤\x03仌\x03冬\x03况\x03凵\x03刃\x03㓟\x03刻\x03剆\x03剷\x03㔕\x03勇\x03勉\x03" +
+	"勤\x03勺\x03包\x03匆\x03北\x03卉\x03卑\x03博\x03即\x03卽\x03卿\x03灰\x03及\x03叟\x03" +
+	"叫\x03叱\x03吆\x03咞\x03吸\x03呈\x03周\x03咢\x03哶\x03唐\x03啓\x03啣\x03善\x03喙\x03" +
+	"喫\x03喳\x03嗂\x03圖\x03嘆\x03圗\x03噑\x03噴\x03切\x03壮\x03城\x03埴\x03堍\x03型\x03" +
+	"堲\x03報\x03墬\x03売\x03壷\x03夆\x03夢\x03奢\x03姬\x03娛\x03娧\x03姘\x03婦\x03㛮\x03" +
+	"嬈\x03嬾\x03寃\x03寘\x03寧\x03寳\x03寿\x03将\x03尢\x03㞁\x03屠\x03屮\x03峀\x03岍\x03" +
+	"嵃\x03嵮\x03嵫\x03嵼\x03巡\x03巢\x03㠯\x03巽\x03帨\x03帽\x03幩\x03㡢\x03㡼\x03庰\x03" +
+	"庳\x03庶\x03廊\x03廾\x03舁\x03弢\x03㣇\x03形\x03彫\x03㣣\x03徚\x03忍\x03志\x03忹\x03" +
+	"悁\x03㤺\x03㤜\x03悔\x03惇\x03慈\x03慌\x03慎\x03慺\x03憎\x03憲\x03憤\x03憯\x03懞\x03" +
+	"懲\x03懶\x03成\x03戛\x03扝\x03抱\x03拔\x03捐\x03挽\x03拼\x03捨\x03掃\x03揤\x03搢\x03" +
+	"揅\x03掩\x03㨮\x03摩\x03摾\x03撝\x03摷\x03㩬\x03敏\x03敬\x03旣\x03書\x03晉\x03㬙\x03" +
+	"暑\x03㬈\x03㫤\x03冒\x03冕\x03最\x03暜\x03肭\x03䏙\x03朗\x03望\x03朡\x03杞\x03杓\x03" +
+	"㭉\x03柺\x03枅\x03桒\x03梅\x03梎\x03栟\x03椔\x03㮝\x03楂\x03榣\x03槪\x03檨\x03櫛\x03" +
+	"㰘\x03次\x03歔\x03㱎\x03歲\x03殟\x03殺\x03殻\x03汎\x03沿\x03泍\x03汧\x03洖\x03派\x03" +
+	"海\x03流\x03浩\x03浸\x03涅\x03洴\x03港\x03湮\x03㴳\x03滋\x03滇\x03淹\x03潮\x03濆\x03" +
+	"瀹\x03瀞\x03瀛\x03㶖\x03灊\x03災\x03灷\x03炭\x03煅\x03熜\x03爨\x03爵\x03牐\x03犀\x03" +
+	"犕\x03獺\x03王\x03㺬\x03玥\x03㺸\x03瑇\x03瑜\x03瑱\x03璅\x03瓊\x03㼛\x03甤\x03甾\x03" +
+	"異\x03瘐\x03㿼\x03䀈\x03直\x03眞\x03真\x03睊\x03䀹\x03瞋\x03䁆\x03䂖\x03硎\x03碌\x03" +
+	"磌\x03䃣\x03祖\x03福\x03秫\x03䄯\x03穀\x03穊\x03穏\x03䈂\x03篆\x03築\x03䈧\x03糒\x03" +
+	"䊠\x03糨\x03糣\x03紀\x03絣\x03䌁\x03緇\x03縂\x03繅\x03䌴\x03䍙\x03罺\x03羕\x03翺\x03" +
+	"者\x03聠\x03聰\x03䏕\x03育\x03脃\x03䐋\x03脾\x03媵\x03舄\x03辞\x03䑫\x03芑\x03芋\x03" +
+	"芝\x03劳\x03花\x03芳\x03芽\x03苦\x03若\x03茝\x03荣\x03莭\x03茣\x03莽\x03菧\x03著\x03" +
+	"荓\x03菊\x03菌\x03菜\x03䔫\x03蓱\x03蓳\x03蔖\x03蕤\x03䕝\x03䕡\x03䕫\x03虐\x03虜\x03" +
+	"虧\x03虩\x03蚩\x03蚈\x03蜎\x03蛢\x03蝹\x03蜨\x03蝫\x03螆\x03蟡\x03蠁\x03䗹\x03衠\x03" +
+	"衣\x03裗\x03裞\x03䘵\x03裺\x03㒻\x03䚾\x03䛇\x03誠\x03諭\x03變\x03豕\x03貫\x03賁\x03" +
+	"贛\x03起\x03跋\x03趼\x03跰\x03軔\x03輸\x03邔\x03郱\x03鄑\x03鄛\x03鈸\x03鋗\x03鋘\x03" +
+	"鉼\x03鏹\x03鐕\x03開\x03䦕\x03閷\x03䧦\x03雃\x03嶲\x03霣\x03䩮\x03䩶\x03韠\x03䪲\x03" +
+	"頋\x03頩\x03飢\x03䬳\x03餩\x03馧\x03駂\x03駾\x03䯎\x03鬒\x03鱀\x03鳽\x03䳎\x03䳭\x03" +
+	"鵧\x03䳸\x03麻\x03䵖\x03黹\x03黾\x03鼅\x03鼏\x03鼖\x03鼻"
+
+var xorData string = "" + // Size: 4855 bytes
+	"\x02\x0c\x09\x02\xb0\xec\x02\xad\xd8\x02\xad\xd9\x02\x06\x07\x02\x0f\x12" +
+	"\x02\x0f\x1f\x02\x0f\x1d\x02\x01\x13\x02\x0f\x16\x02\x0f\x0b\x02\x0f3" +
+	"\x02\x0f7\x02\x0f?\x02\x0f/\x02\x0f*\x02\x0c&\x02\x0c*\x02\x0c;\x02\x0c9" +
+	"\x02\x0c%\x02\xab\xed\x02\xab\xe2\x02\xab\xe3\x02\xa9\xe0\x02\xa9\xe1" +
+	"\x02\xa9\xe6\x02\xa3\xcb\x02\xa3\xc8\x02\xa3\xc9\x02\x01#\x02\x01\x08" +
+	"\x02\x0e>\x02\x0e'\x02\x0f\x03\x02\x03\x0d\x02\x03\x09\x02\x03\x17\x02" +
+	"\x03\x0e\x02\x02\x03\x02\x011\x02\x01\x00\x02\x01\x10\x02\x03<\x02\x07" +
+	"\x0d\x02\x02\x0c\x02\x0c0\x02\x01\x03\x02\x01\x01\x02\x01 \x02\x01\x22" +
+	"\x02\x01)\x02\x01\x0a\x02\x01\x0c\x02\x02\x06\x02\x02\x02\x02\x03\x10" +
+	"\x03\x037 \x03\x0b+\x03\x02\x01\x04\x02\x01\x02\x02\x019\x02\x03\x1c\x02" +
+	"\x02$\x03\x80p$\x02\x03:\x02\x03\x0a\x03\xc1r.\x03\xc1r,\x03\xc1r\x02" +
+	"\x02\x02:\x02\x02>\x02\x02,\x02\x02\x10\x02\x02\x00\x03\xc1s<\x03\xc1s*" +
+	"\x03\xc2L$\x03\xc2L;\x02\x09)\x02\x0a\x19\x03\x83\xab\xe3\x03\x83\xab" +
+	"\xf2\x03 4\xe0\x03\x81\xab\xea\x03\x81\xab\xf3\x03 4\xef\x03\x96\xe1\xcd" +
+	"\x03\x84\xe5\xc3\x02\x0d\x11\x03\x8b\xec\xcb\x03\x94\xec\xcf\x03\x9a\xec" +
+	"\xc2\x03\x8b\xec\xdb\x03\x94\xec\xdf\x03\x9a\xec\xd2\x03\x01\x0c!\x03" +
+	"\x01\x0c#\x03ʠ\x9d\x03ʣ\x9c\x03ʢ\x9f\x03ʥ\x9e\x03ʤ\x91\x03ʧ\x90\x03ʦ\x93" +
+	"\x03ʩ\x92\x03ʨ\x95\x03\xca\xf3\xb5\x03\xca\xf0\xb4\x03\xca\xf1\xb7\x03" +
+	"\xca\xf6\xb6\x03\xca\xf7\x89\x03\xca\xf4\x88\x03\xca\xf5\x8b\x03\xca\xfa" +
+	"\x8a\x03\xca\xfb\x8d\x03\xca\xf8\x8c\x03\xca\xf9\x8f\x03\xca\xfe\x8e\x03" +
+	"\xca\xff\x81\x03\xca\xfc\x80\x03\xca\xfd\x83\x03\xca\xe2\x82\x03\xca\xe3" +
+	"\x85\x03\xca\xe0\x84\x03\xca\xe1\x87\x03\xca\xe6\x86\x03\xca\xe7\x99\x03" +
+	"\xca\xe4\x98\x03\xca\xe5\x9b\x03\xca\xea\x9a\x03\xca\xeb\x9d\x03\xca\xe8" +
+	"\x9c\x03ؓ\x89\x03ߔ\x8b\x02\x010\x03\x03\x04\x1e\x03\x04\x15\x12\x03\x0b" +
+	"\x05,\x03\x06\x04\x00\x03\x06\x04)\x03\x06\x044\x03\x06\x04<\x03\x06\x05" +
+	"\x1d\x03\x06\x06\x00\x03\x06\x06\x0a\x03\x06\x06'\x03\x06\x062\x03\x0786" +
+	"\x03\x079/\x03\x079 \x03\x07:\x0e\x03\x07:\x1b\x03\x07:%\x03\x07;/\x03" +
+	"\x07;%\x03\x074\x11\x03\x076\x09\x03\x077*\x03\x070\x01\x03\x070\x0f\x03" +
+	"\x070.\x03\x071\x16\x03\x071\x04\x03\x0710\x03\x072\x18\x03\x072-\x03" +
+	"\x073\x14\x03\x073>\x03\x07'\x09\x03\x07 \x00\x03\x07\x1f\x0b\x03\x07" +
+	"\x18#\x03\x07\x18(\x03\x07\x186\x03\x07\x18\x03\x03\x07\x19\x16\x03\x07" +
+	"\x116\x03\x07\x12'\x03\x07\x13\x10\x03\x07\x0c&\x03\x07\x0c\x08\x03\x07" +
+	"\x0c\x13\x03\x07\x0d\x02\x03\x07\x0d\x1c\x03\x07\x0b5\x03\x07\x0b\x0a" +
+	"\x03\x07\x0b\x01\x03\x07\x0b\x0f\x03\x07\x05\x00\x03\x07\x05\x09\x03\x07" +
+	"\x05\x0b\x03\x07\x07\x01\x03\x07\x07\x08\x03\x07\x00<\x03\x07\x00+\x03" +
+	"\x07\x01)\x03\x07\x01\x1b\x03\x07\x01\x08\x03\x07\x03?\x03\x0445\x03\x04" +
+	"4\x08\x03\x0454\x03\x04)/\x03\x04)5\x03\x04+\x05\x03\x04+\x14\x03\x04+ " +
+	"\x03\x04+<\x03\x04*&\x03\x04*\x22\x03\x04&8\x03\x04!\x01\x03\x04!\x22" +
+	"\x03\x04\x11+\x03\x04\x10.\x03\x04\x104\x03\x04\x13=\x03\x04\x12\x04\x03" +
+	"\x04\x12\x0a\x03\x04\x0d\x1d\x03\x04\x0d\x07\x03\x04\x0d \x03\x05<>\x03" +
+	"\x055<\x03\x055!\x03\x055#\x03\x055&\x03\x054\x1d\x03\x054\x02\x03\x054" +
+	"\x07\x03\x0571\x03\x053\x1a\x03\x053\x16\x03\x05.<\x03\x05.\x07\x03\x05)" +
+	":\x03\x05)<\x03\x05)\x0c\x03\x05)\x15\x03\x05+-\x03\x05+5\x03\x05$\x1e" +
+	"\x03\x05$\x14\x03\x05'\x04\x03\x05'\x14\x03\x05&\x02\x03\x05\x226\x03" +
+	"\x05\x22\x0c\x03\x05\x22\x1c\x03\x05\x19\x0a\x03\x05\x1b\x09\x03\x05\x1b" +
+	"\x0c\x03\x05\x14\x07\x03\x05\x16?\x03\x05\x16\x0c\x03\x05\x0c\x05\x03" +
+	"\x05\x0e\x0f\x03\x05\x01\x0e\x03\x05\x00(\x03\x05\x030\x03\x05\x03\x06" +
+	"\x03\x0a==\x03\x0a=1\x03\x0a=,\x03\x0a=\x0c\x03\x0a??\x03\x0a<\x08\x03" +
+	"\x0a9!\x03\x0a9)\x03\x0a97\x03\x0a99\x03\x0a6\x0a\x03\x0a6\x1c\x03\x0a6" +
+	"\x17\x03\x0a7'\x03\x0a78\x03\x0a73\x03\x0a'\x01\x03\x0a'&\x03\x0a\x1f" +
+	"\x0e\x03\x0a\x1f\x03\x03\x0a\x1f3\x03\x0a\x1b/\x03\x0a\x18\x19\x03\x0a" +
+	"\x19\x01\x03\x0a\x16\x14\x03\x0a\x0e\x22\x03\x0a\x0f\x10\x03\x0a\x0f\x02" +
+	"\x03\x0a\x0f \x03\x0a\x0c\x04\x03\x0a\x0b>\x03\x0a\x0b+\x03\x0a\x08/\x03" +
+	"\x0a\x046\x03\x0a\x05\x14\x03\x0a\x00\x04\x03\x0a\x00\x10\x03\x0a\x00" +
+	"\x14\x03\x0b<3\x03\x0b;*\x03\x0b9\x22\x03\x0b9)\x03\x0b97\x03\x0b+\x10" +
+	"\x03\x0b((\x03\x0b&5\x03\x0b$\x1c\x03\x0b$\x12\x03\x0b%\x04\x03\x0b#<" +
+	"\x03\x0b#0\x03\x0b#\x0d\x03\x0b#\x19\x03\x0b!:\x03\x0b!\x1f\x03\x0b!\x00" +
+	"\x03\x0b\x1e5\x03\x0b\x1c\x1d\x03\x0b\x1d-\x03\x0b\x1d(\x03\x0b\x18.\x03" +
+	"\x0b\x18 \x03\x0b\x18\x16\x03\x0b\x14\x13\x03\x0b\x15$\x03\x0b\x15\x22" +
+	"\x03\x0b\x12\x1b\x03\x0b\x12\x10\x03\x0b\x132\x03\x0b\x13=\x03\x0b\x12" +
+	"\x18\x03\x0b\x0c&\x03\x0b\x061\x03\x0b\x06:\x03\x0b\x05#\x03\x0b\x05<" +
+	"\x03\x0b\x04\x0b\x03\x0b\x04\x04\x03\x0b\x04\x1b\x03\x0b\x042\x03\x0b" +
+	"\x041\x03\x0b\x03\x03\x03\x0b\x03\x1d\x03\x0b\x03/\x03\x0b\x03+\x03\x0b" +
+	"\x02\x1b\x03\x0b\x02\x00\x03\x0b\x01\x1e\x03\x0b\x01\x08\x03\x0b\x015" +
+	"\x03\x06\x0d9\x03\x06\x0d=\x03\x06\x0d?\x03\x02\x001\x03\x02\x003\x03" +
+	"\x02\x02\x19\x03\x02\x006\x03\x02\x02\x1b\x03\x02\x004\x03\x02\x00<\x03" +
+	"\x02\x02\x0a\x03\x02\x02\x0e\x03\x02\x01\x1a\x03\x02\x01\x07\x03\x02\x01" +
+	"\x05\x03\x02\x01\x0b\x03\x02\x01%\x03\x02\x01\x0c\x03\x02\x01\x04\x03" +
+	"\x02\x01\x1c\x03\x02\x00.\x03\x02\x002\x03\x02\x00>\x03\x02\x00\x12\x03" +
+	"\x02\x00\x16\x03\x02\x011\x03\x02\x013\x03\x02\x02 \x03\x02\x02%\x03\x02" +
+	"\x02$\x03\x02\x028\x03\x02\x02;\x03\x02\x024\x03\x02\x012\x03\x02\x022" +
+	"\x03\x02\x02/\x03\x02\x01,\x03\x02\x01\x13\x03\x02\x01\x16\x03\x02\x01" +
+	"\x11\x03\x02\x01\x1e\x03\x02\x01\x15\x03\x02\x01\x17\x03\x02\x01\x0f\x03" +
+	"\x02\x01\x08\x03\x02\x00?\x03\x02\x03\x07\x03\x02\x03\x0d\x03\x02\x03" +
+	"\x13\x03\x02\x03\x1d\x03\x02\x03\x1f\x03\x02\x00\x03\x03\x02\x00\x0d\x03" +
+	"\x02\x00\x01\x03\x02\x00\x1b\x03\x02\x00\x19\x03\x02\x00\x18\x03\x02\x00" +
+	"\x13\x03\x02\x00/\x03\x07>\x12\x03\x07<\x1f\x03\x07>\x1d\x03\x06\x1d\x0e" +
+	"\x03\x07>\x1c\x03\x07>:\x03\x07>\x13\x03\x04\x12+\x03\x07?\x03\x03\x07>" +
+	"\x02\x03\x06\x224\x03\x06\x1a.\x03\x07<%\x03\x06\x1c\x0b\x03\x0609\x03" +
+	"\x05\x1f\x01\x03\x04'\x08\x03\x93\xfd\xf5\x03\x02\x0d \x03\x02\x0d#\x03" +
+	"\x02\x0d!\x03\x02\x0d&\x03\x02\x0d\x22\x03\x02\x0d/\x03\x02\x0d,\x03\x02" +
+	"\x0d$\x03\x02\x0d'\x03\x02\x0d%\x03\x02\x0d;\x03\x02\x0d=\x03\x02\x0d?" +
+	"\x03\x099.\x03\x08\x0b7\x03\x08\x02\x14\x03\x08\x14\x0d\x03\x08.:\x03" +
+	"\x089'\x03\x0f\x0b\x18\x03\x0f\x1c1\x03\x0f\x17&\x03\x0f9\x1f\x03\x0f0" +
+	"\x0c\x03\x0e\x0a9\x03\x0e\x056\x03\x0e\x1c#\x03\x0f\x13\x0e\x03\x072\x00" +
+	"\x03\x070\x0d\x03\x072\x0b\x03\x06\x11\x18\x03\x070\x10\x03\x06\x0f(\x03" +
+	"\x072\x05\x03\x06\x0f,\x03\x073\x15\x03\x06\x07\x08\x03\x05\x16\x02\x03" +
+	"\x04\x0b \x03\x05:8\x03\x05\x16%\x03\x0a\x0d\x1f\x03\x06\x16\x10\x03\x05" +
+	"\x1d5\x03\x05*;\x03\x05\x16\x1b\x03\x04.-\x03\x06\x1a\x19\x03\x04\x03," +
+	"\x03\x0b87\x03\x04/\x0a\x03\x06\x00,\x03\x04-\x01\x03\x04\x1e-\x03\x06/(" +
+	"\x03\x0a\x0b5\x03\x06\x0e7\x03\x06\x07.\x03\x0597\x03\x0a*%\x03\x0760" +
+	"\x03\x06\x0c;\x03\x05'\x00\x03\x072.\x03\x072\x08\x03\x06=\x01\x03\x06" +
+	"\x05\x1b\x03\x06\x06\x12\x03\x06$=\x03\x06'\x0d\x03\x04\x11\x0f\x03\x076" +
+	",\x03\x06\x07;\x03\x06.,\x03\x86\xf9\xea\x03\x8f\xff\xeb\x02\x092\x02" +
+	"\x095\x02\x094\x02\x09;\x02\x09>\x02\x098\x02\x09*\x02\x09/\x02\x09,\x02" +
+	"\x09%\x02\x09&\x02\x09#\x02\x09 \x02\x08!\x02\x08%\x02\x08$\x02\x08+\x02" +
+	"\x08.\x02\x08*\x02\x08&\x02\x088\x02\x08>\x02\x084\x02\x086\x02\x080\x02" +
+	"\x08\x10\x02\x08\x17\x02\x08\x12\x02\x08\x1d\x02\x08\x1f\x02\x08\x13\x02" +
+	"\x08\x15\x02\x08\x14\x02\x08\x0c\x03\x8b\xfd\xd0\x03\x81\xec\xc6\x03\x87" +
+	"\xe0\x8a\x03-2\xe3\x03\x80\xef\xe4\x03-2\xea\x03\x88\xe6\xeb\x03\x8e\xe6" +
+	"\xe8\x03\x84\xe6\xe9\x03\x97\xe6\xee\x03-2\xf9\x03-2\xf6\x03\x8e\xe3\xad" +
+	"\x03\x80\xe3\x92\x03\x88\xe3\x90\x03\x8e\xe3\x90\x03\x80\xe3\x97\x03\x88" +
+	"\xe3\x95\x03\x88\xfe\xcb\x03\x8e\xfe\xca\x03\x84\xfe\xcd\x03\x91\xef\xc9" +
+	"\x03-2\xc1\x03-2\xc0\x03-2\xcb\x03\x88@\x09\x03\x8e@\x08\x03\x8f\xe0\xf5" +
+	"\x03\x8e\xe6\xf9\x03\x8e\xe0\xfa\x03\x93\xff\xf4\x03\x84\xee\xd3\x03\x0b" +
+	"(\x04\x023 \x021;\x02\x01*\x03\x0b#\x10\x03\x0b 0\x03\x0b!\x10\x03\x0b!0" +
+	"\x03\x07\x15\x08\x03\x09?5\x03\x07\x1f\x08\x03\x07\x17\x0b\x03\x09\x1f" +
+	"\x15\x03\x0b\x1c7\x03\x0a+#\x03\x06\x1a\x1b\x03\x06\x1a\x14\x03\x0a\x01" +
+	"\x18\x03\x06#\x1b\x03\x0a2\x0c\x03\x0a\x01\x04\x03\x09#;\x03\x08='\x03" +
+	"\x08\x1a\x0a\x03\x07</\x03\x07:+\x03\x07\x07*\x03\x06&\x1c\x03\x09\x0c" +
+	"\x16\x03\x09\x10\x0e\x03\x08'\x0f\x03\x08+\x09\x03\x074%\x03\x06!3\x03" +
+	"\x06\x03+\x03\x0b\x1e\x19\x03\x0a))\x03\x09\x08\x19\x03\x08,\x05\x03\x07" +
+	"<2\x03\x06\x1c>\x03\x0a\x111\x03\x09\x1b\x09\x03\x073.\x03\x07\x01\x00" +
+	"\x03\x09/,\x03\x07#>\x03\x07\x048\x03\x0a\x1f\x22\x03\x098>\x03\x09\x11" +
+	"\x00\x03\x08/\x17\x03\x06'\x22\x03\x0b\x1a+\x03\x0a\x22\x19\x03\x0a/1" +
+	"\x03\x0974\x03\x09\x0f\x22\x03\x08,\x22\x03\x08?\x14\x03\x07$5\x03\x07<3" +
+	"\x03\x07=*\x03\x07\x13\x18\x03\x068\x0a\x03\x06\x09\x16\x03\x06\x13\x00" +
+	"\x03\x08\x067\x03\x08\x01\x03\x03\x08\x12\x1d\x03\x07+7\x03\x06(;\x03" +
+	"\x06\x1c?\x03\x07\x0e\x17\x03\x0a\x06\x1d\x03\x0a\x19\x07\x03\x08\x14$" +
+	"\x03\x07$;\x03\x08,$\x03\x08\x06\x0d\x03\x07\x16\x0a\x03\x06>>\x03\x0a" +
+	"\x06\x12\x03\x0a\x14)\x03\x09\x0d\x1f\x03\x09\x12\x17\x03\x09\x19\x01" +
+	"\x03\x08\x11 \x03\x08\x1d'\x03\x06<\x1a\x03\x0a.\x00\x03\x07'\x18\x03" +
+	"\x0a\x22\x08\x03\x08\x0d\x0a\x03\x08\x13)\x03\x07*)\x03\x06<,\x03\x07" +
+	"\x0b\x1a\x03\x09.\x14\x03\x09\x0d\x1e\x03\x07\x0e#\x03\x0b\x1d'\x03\x0a" +
+	"\x0a8\x03\x09%2\x03\x08+&\x03\x080\x12\x03\x0a)4\x03\x08\x06\x1f\x03\x0b" +
+	"\x1b\x1a\x03\x0a\x1b\x0f\x03\x0b\x1d*\x03\x09\x16$\x03\x090\x11\x03\x08" +
+	"\x11\x08\x03\x0a*(\x03\x0a\x042\x03\x089,\x03\x074'\x03\x07\x0f\x05\x03" +
+	"\x09\x0b\x0a\x03\x07\x1b\x01\x03\x09\x17:\x03\x09.\x0d\x03\x07.\x11\x03" +
+	"\x09+\x15\x03\x080\x13\x03\x0b\x1f\x19\x03\x0a \x11\x03\x0a\x220\x03\x09" +
+	"\x07;\x03\x08\x16\x1c\x03\x07,\x13\x03\x07\x0e/\x03\x06\x221\x03\x0a." +
+	"\x0a\x03\x0a7\x02\x03\x0a\x032\x03\x0a\x1d.\x03\x091\x06\x03\x09\x19:" +
+	"\x03\x08\x02/\x03\x060+\x03\x06\x0f-\x03\x06\x1c\x1f\x03\x06\x1d\x07\x03" +
+	"\x0a,\x11\x03\x09=\x0d\x03\x09\x0b;\x03\x07\x1b/\x03\x0a\x1f:\x03\x09 " +
+	"\x1f\x03\x09.\x10\x03\x094\x0b\x03\x09\x1a1\x03\x08#\x1a\x03\x084\x1d" +
+	"\x03\x08\x01\x1f\x03\x08\x11\x22\x03\x07'8\x03\x07\x1a>\x03\x0757\x03" +
+	"\x06&9\x03\x06+\x11\x03\x0a.\x0b\x03\x0a,>\x03\x0a4#\x03\x08%\x17\x03" +
+	"\x07\x05\x22\x03\x07\x0c\x0b\x03\x0a\x1d+\x03\x0a\x19\x16\x03\x09+\x1f" +
+	"\x03\x09\x08\x0b\x03\x08\x16\x18\x03\x08+\x12\x03\x0b\x1d\x0c\x03\x0a=" +
+	"\x10\x03\x0a\x09\x0d\x03\x0a\x10\x11\x03\x09&0\x03\x08(\x1f\x03\x087\x07" +
+	"\x03\x08\x185\x03\x07'6\x03\x06.\x05\x03\x06=\x04\x03\x06;;\x03\x06\x06," +
+	"\x03\x0b\x18>\x03\x08\x00\x18\x03\x06 \x03\x03\x06<\x00\x03\x09%\x18\x03" +
+	"\x0b\x1c<\x03\x0a%!\x03\x0a\x09\x12\x03\x0a\x16\x02\x03\x090'\x03\x09" +
+	"\x0e=\x03\x08 \x0e\x03\x08>\x03\x03\x074>\x03\x06&?\x03\x06\x19\x09\x03" +
+	"\x06?(\x03\x0a-\x0e\x03\x09:3\x03\x098:\x03\x09\x12\x0b\x03\x09\x1d\x17" +
+	"\x03\x087\x05\x03\x082\x14\x03\x08\x06%\x03\x08\x13\x1f\x03\x06\x06\x0e" +
+	"\x03\x0a\x22<\x03\x09/<\x03\x06>+\x03\x0a'?\x03\x0a\x13\x0c\x03\x09\x10<" +
+	"\x03\x07\x1b=\x03\x0a\x19\x13\x03\x09\x22\x1d\x03\x09\x07\x0d\x03\x08)" +
+	"\x1c\x03\x06=\x1a\x03\x0a/4\x03\x0a7\x11\x03\x0a\x16:\x03\x09?3\x03\x09:" +
+	"/\x03\x09\x05\x0a\x03\x09\x14\x06\x03\x087\x22\x03\x080\x07\x03\x08\x1a" +
+	"\x1f\x03\x07\x04(\x03\x07\x04\x09\x03\x06 %\x03\x06<\x08\x03\x0a+\x14" +
+	"\x03\x09\x1d\x16\x03\x0a70\x03\x08 >\x03\x0857\x03\x070\x0a\x03\x06=\x12" +
+	"\x03\x06\x16%\x03\x06\x1d,\x03\x099#\x03\x09\x10>\x03\x07 \x1e\x03\x08" +
+	"\x0c<\x03\x08\x0b\x18\x03\x08\x15+\x03\x08,:\x03\x08%\x22\x03\x07\x0a$" +
+	"\x03\x0b\x1c=\x03\x07+\x08\x03\x0a/\x05\x03\x0a \x07\x03\x0a\x12'\x03" +
+	"\x09#\x11\x03\x08\x1b\x15\x03\x0a\x06\x01\x03\x09\x1c\x1b\x03\x0922\x03" +
+	"\x07\x14<\x03\x07\x09\x04\x03\x061\x04\x03\x07\x0e\x01\x03\x0a\x13\x18" +
+	"\x03\x0a-\x0c\x03\x0a?\x0d\x03\x0a\x09\x0a\x03\x091&\x03\x0a/\x0b\x03" +
+	"\x08$<\x03\x083\x1d\x03\x08\x0c$\x03\x08\x0d\x07\x03\x08\x0d?\x03\x08" +
+	"\x0e\x14\x03\x065\x0a\x03\x08\x1a#\x03\x08\x16#\x03\x0702\x03\x07\x03" +
+	"\x1a\x03\x06(\x1d\x03\x06+\x1b\x03\x06\x0b\x05\x03\x06\x0b\x17\x03\x06" +
+	"\x0c\x04\x03\x06\x1e\x19\x03\x06+0\x03\x062\x18\x03\x0b\x16\x1e\x03\x0a+" +
+	"\x16\x03\x0a-?\x03\x0a#:\x03\x0a#\x10\x03\x0a%$\x03\x0a>+\x03\x0a01\x03" +
+	"\x0a1\x10\x03\x0a\x099\x03\x0a\x0a\x12\x03\x0a\x19\x1f\x03\x0a\x19\x12" +
+	"\x03\x09*)\x03\x09-\x16\x03\x09.1\x03\x09.2\x03\x09<\x0e\x03\x09> \x03" +
+	"\x093\x12\x03\x09\x0b\x01\x03\x09\x1c2\x03\x09\x11\x1c\x03\x09\x15%\x03" +
+	"\x08,&\x03\x08!\x22\x03\x089(\x03\x08\x0b\x1a\x03\x08\x0d2\x03\x08\x0c" +
+	"\x04\x03\x08\x0c\x06\x03\x08\x0c\x1f\x03\x08\x0c\x0c\x03\x08\x0f\x1f\x03" +
+	"\x08\x0f\x1d\x03\x08\x00\x14\x03\x08\x03\x14\x03\x08\x06\x16\x03\x08\x1e" +
+	"#\x03\x08\x11\x11\x03\x08\x10\x18\x03\x08\x14(\x03\x07)\x1e\x03\x07.1" +
+	"\x03\x07 $\x03\x07 '\x03\x078\x08\x03\x07\x0d0\x03\x07\x0f7\x03\x07\x05#" +
+	"\x03\x07\x05\x1a\x03\x07\x1a7\x03\x07\x1d-\x03\x07\x17\x10\x03\x06)\x1f" +
+	"\x03\x062\x0b\x03\x066\x16\x03\x06\x09\x11\x03\x09(\x1e\x03\x07!5\x03" +
+	"\x0b\x11\x16\x03\x0a/\x04\x03\x0a,\x1a\x03\x0b\x173\x03\x0a,1\x03\x0a/5" +
+	"\x03\x0a\x221\x03\x0a\x22\x0d\x03\x0a?%\x03\x0a<,\x03\x0a?#\x03\x0a>\x19" +
+	"\x03\x0a\x08&\x03\x0a\x0b\x0e\x03\x0a\x0c:\x03\x0a\x0c+\x03\x0a\x03\x22" +
+	"\x03\x0a\x06)\x03\x0a\x11\x10\x03\x0a\x11\x1a\x03\x0a\x17-\x03\x0a\x14(" +
+	"\x03\x09)\x1e\x03\x09/\x09\x03\x09.\x00\x03\x09,\x07\x03\x09/*\x03\x09-9" +
+	"\x03\x09\x228\x03\x09%\x09\x03\x09:\x12\x03\x09;\x1d\x03\x09?\x06\x03" +
+	"\x093%\x03\x096\x05\x03\x096\x08\x03\x097\x02\x03\x09\x07,\x03\x09\x04," +
+	"\x03\x09\x1f\x16\x03\x09\x11\x03\x03\x09\x11\x12\x03\x09\x168\x03\x08*" +
+	"\x05\x03\x08/2\x03\x084:\x03\x08\x22+\x03\x08 0\x03\x08&\x0a\x03\x08;" +
+	"\x10\x03\x08>$\x03\x08>\x18\x03\x0829\x03\x082:\x03\x081,\x03\x081<\x03" +
+	"\x081\x1c\x03\x087#\x03\x087*\x03\x08\x09'\x03\x08\x00\x1d\x03\x08\x05-" +
+	"\x03\x08\x1f4\x03\x08\x1d\x04\x03\x08\x16\x0f\x03\x07*7\x03\x07'!\x03" +
+	"\x07%\x1b\x03\x077\x0c\x03\x07\x0c1\x03\x07\x0c.\x03\x07\x00\x06\x03\x07" +
+	"\x01\x02\x03\x07\x010\x03\x07\x06=\x03\x07\x01\x03\x03\x07\x01\x13\x03" +
+	"\x07\x06\x06\x03\x07\x05\x0a\x03\x07\x1f\x09\x03\x07\x17:\x03\x06*1\x03" +
+	"\x06-\x1d\x03\x06\x223\x03\x062:\x03\x060$\x03\x066\x1e\x03\x064\x12\x03" +
+	"\x0645\x03\x06\x0b\x00\x03\x06\x0b7\x03\x06\x07\x1f\x03\x06\x15\x12\x03" +
+	"\x0c\x05\x0f\x03\x0b+\x0b\x03\x0b+-\x03\x06\x16\x1b\x03\x06\x15\x17\x03" +
+	"\x89\xca\xea\x03\x89\xca\xe8\x03\x0c8\x10\x03\x0c8\x01\x03\x0c8\x0f\x03" +
+	"\x0d8%\x03\x0d8!\x03\x0c8-\x03\x0c8/\x03\x0c8+\x03\x0c87\x03\x0c85\x03" +
+	"\x0c9\x09\x03\x0c9\x0d\x03\x0c9\x0f\x03\x0c9\x0b\x03\xcfu\x0c\x03\xcfu" +
+	"\x0f\x03\xcfu\x0e\x03\xcfu\x09\x03\x0c9\x10\x03\x0d9\x0c\x03\xcf`;\x03" +
+	"\xcf`>\x03\xcf`9\x03\xcf`8\x03\xcf`7\x03\xcf`*\x03\xcf`-\x03\xcf`,\x03" +
+	"\x0d\x1b\x1a\x03\x0d\x1b&\x03\x0c=.\x03\x0c=%\x03\x0c>\x1e\x03\x0c>\x14" +
+	"\x03\x0c?\x06\x03\x0c?\x0b\x03\x0c?\x0c\x03\x0c?\x0d\x03\x0c?\x02\x03" +
+	"\x0c>\x0f\x03\x0c>\x08\x03\x0c>\x09\x03\x0c>,\x03\x0c>\x0c\x03\x0c?\x13" +
+	"\x03\x0c?\x16\x03\x0c?\x15\x03\x0c?\x1c\x03\x0c?\x1f\x03\x0c?\x1d\x03" +
+	"\x0c?\x1a\x03\x0c?\x17\x03\x0c?\x08\x03\x0c?\x09\x03\x0c?\x0e\x03\x0c?" +
+	"\x04\x03\x0c?\x05\x03\x0c<?\x03\x0c=\x00\x03\x0c=\x06\x03\x0c=\x05\x03" +
+	"\x0c=\x0c\x03\x0c=\x0f\x03\x0c=\x0d\x03\x0c=\x0b\x03\x0c=\x07\x03\x0c=" +
+	"\x19\x03\x0c=\x15\x03\x0c=\x11\x03\x0c=1\x03\x0c=3\x03\x0c=0\x03\x0c=>" +
+	"\x03\x0c=2\x03\x0c=6\x03\x0c<\x07\x03\x0c<\x05\x03\x0e:!\x03\x0e:#\x03" +
+	"\x0e8\x09\x03\x0e:&\x03\x0e8\x0b\x03\x0e:$\x03\x0e:,\x03\x0e8\x1a\x03" +
+	"\x0e8\x1e\x03\x0e:*\x03\x0e:7\x03\x0e:5\x03\x0e:;\x03\x0e:\x15\x03\x0e:<" +
+	"\x03\x0e:4\x03\x0e:'\x03\x0e:-\x03\x0e:%\x03\x0e:?\x03\x0e:=\x03\x0e:)" +
+	"\x03\x0e:/\x03\xcfs'\x03\x0d=\x0f\x03\x0d+*\x03\x0d99\x03\x0d9;\x03\x0d9" +
+	"?\x03\x0d)\x0d\x03\x0d(%\x02\x01\x18\x02\x01(\x02\x01\x1e\x03\x0f$!\x03" +
+	"\x0f87\x03\x0f4\x0e\x03\x0f5\x1d\x03\x06'\x03\x03\x0f\x08\x18\x03\x0f" +
+	"\x0d\x1b\x03\x0e2=\x03\x0e;\x08\x03\x0e:\x0b\x03\x0e\x06$\x03\x0e\x0d)" +
+	"\x03\x0e\x16\x1f\x03\x0e\x16\x1b\x03\x0d$\x0a\x03\x05,\x1d\x03\x0d. \x03" +
+	"\x0d.#\x03\x0c(/\x03\x09%\x02\x03\x0d90\x03\x0d\x0e4\x03\x0d\x0d\x0f\x03" +
+	"\x0c#\x00\x03\x0c,\x1e\x03\x0c2\x0e\x03\x0c\x01\x17\x03\x0c\x09:\x03\x0e" +
+	"\x173\x03\x0c\x08\x03\x03\x0c\x11\x07\x03\x0c\x10\x18\x03\x0c\x1f\x1c" +
+	"\x03\x0c\x19\x0e\x03\x0c\x1a\x1f\x03\x0f0>\x03\x0b->\x03\x0b<+\x03\x0b8" +
+	"\x13\x03\x0b\x043\x03\x0b\x14\x03\x03\x0b\x16%\x03\x0d\x22&\x03\x0b\x1a" +
+	"\x1a\x03\x0b\x1a\x04\x03\x0a%9\x03\x0a&2\x03\x0a&0\x03\x0a!\x1a\x03\x0a!" +
+	"7\x03\x0a5\x10\x03\x0a=4\x03\x0a?\x0e\x03\x0a>\x10\x03\x0a\x00 \x03\x0a" +
+	"\x0f:\x03\x0a\x0f9\x03\x0a\x0b\x0a\x03\x0a\x17%\x03\x0a\x1b-\x03\x09-" +
+	"\x1a\x03\x09,4\x03\x09.,\x03\x09)\x09\x03\x096!\x03\x091\x1f\x03\x093" +
+	"\x16\x03\x0c+\x1f\x03\x098 \x03\x098=\x03\x0c(\x1a\x03\x0c(\x16\x03\x09" +
+	"\x0a+\x03\x09\x16\x12\x03\x09\x13\x0e\x03\x09\x153\x03\x08)!\x03\x09\x1a" +
+	"\x01\x03\x09\x18\x01\x03\x08%#\x03\x08>\x22\x03\x08\x05%\x03\x08\x02*" +
+	"\x03\x08\x15;\x03\x08\x1b7\x03\x0f\x07\x1d\x03\x0f\x04\x03\x03\x070\x0c" +
+	"\x03\x07;\x0b\x03\x07\x08\x17\x03\x07\x12\x06\x03\x06/-\x03\x0671\x03" +
+	"\x065+\x03\x06>7\x03\x06\x049\x03\x05+\x1e\x03\x05,\x17\x03\x05 \x1d\x03" +
+	"\x05\x22\x05\x03\x050\x1d"
+
+// lookup returns the trie value for the first UTF-8 encoding in s and
+// the width in bytes of this encoding. The size will be 0 if s does not
+// hold enough bytes to complete the encoding. len(s) must be greater than 0.
+func (t *idnaTrie) lookup(s []byte) (v uint16, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return idnaValues[c0], 1
+	case c0 < 0xC2:
+		return 0, 1 // Illegal UTF-8: not a starter, not ASCII.
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return 0, 0
+		}
+		i := idnaIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c1), 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return 0, 0
+		}
+		i := idnaIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = idnaIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c2), 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return 0, 0
+		}
+		i := idnaIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = idnaIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = idnaIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return 0, 3 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c3), 4
+	}
+	// Illegal rune
+	return 0, 1
+}
+
+// lookupUnsafe returns the trie value for the first UTF-8 encoding in s.
+// s must start with a full and valid UTF-8 encoded rune.
+func (t *idnaTrie) lookupUnsafe(s []byte) uint16 {
+	c0 := s[0]
+	if c0 < 0x80 { // is ASCII
+		return idnaValues[c0]
+	}
+	i := idnaIndex[c0]
+	if c0 < 0xE0 { // 2-byte UTF-8
+		return t.lookupValue(uint32(i), s[1])
+	}
+	i = idnaIndex[uint32(i)<<6+uint32(s[1])]
+	if c0 < 0xF0 { // 3-byte UTF-8
+		return t.lookupValue(uint32(i), s[2])
+	}
+	i = idnaIndex[uint32(i)<<6+uint32(s[2])]
+	if c0 < 0xF8 { // 4-byte UTF-8
+		return t.lookupValue(uint32(i), s[3])
+	}
+	return 0
+}
+
+// lookupString returns the trie value for the first UTF-8 encoding in s and
+// the width in bytes of this encoding. The size will be 0 if s does not
+// hold enough bytes to complete the encoding. len(s) must be greater than 0.
+func (t *idnaTrie) lookupString(s string) (v uint16, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return idnaValues[c0], 1
+	case c0 < 0xC2:
+		return 0, 1 // Illegal UTF-8: not a starter, not ASCII.
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return 0, 0
+		}
+		i := idnaIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c1), 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return 0, 0
+		}
+		i := idnaIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = idnaIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c2), 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return 0, 0
+		}
+		i := idnaIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = idnaIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = idnaIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return 0, 3 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c3), 4
+	}
+	// Illegal rune
+	return 0, 1
+}
+
+// lookupStringUnsafe returns the trie value for the first UTF-8 encoding in s.
+// s must start with a full and valid UTF-8 encoded rune.
+func (t *idnaTrie) lookupStringUnsafe(s string) uint16 {
+	c0 := s[0]
+	if c0 < 0x80 { // is ASCII
+		return idnaValues[c0]
+	}
+	i := idnaIndex[c0]
+	if c0 < 0xE0 { // 2-byte UTF-8
+		return t.lookupValue(uint32(i), s[1])
+	}
+	i = idnaIndex[uint32(i)<<6+uint32(s[1])]
+	if c0 < 0xF0 { // 3-byte UTF-8
+		return t.lookupValue(uint32(i), s[2])
+	}
+	i = idnaIndex[uint32(i)<<6+uint32(s[2])]
+	if c0 < 0xF8 { // 4-byte UTF-8
+		return t.lookupValue(uint32(i), s[3])
+	}
+	return 0
+}
+
+// idnaTrie. Total size: 28496 bytes (27.83 KiB). Checksum: 43288b883596640e.
+type idnaTrie struct{}
+
+func newIdnaTrie(i int) *idnaTrie {
+	return &idnaTrie{}
+}
+
+// lookupValue determines the type of block n and looks up the value for b.
+func (t *idnaTrie) lookupValue(n uint32, b byte) uint16 {
+	switch {
+	case n < 123:
+		return uint16(idnaValues[n<<6+uint32(b)])
+	default:
+		n -= 123
+		return uint16(idnaSparse.lookup(n, b))
+	}
+}
+
+// idnaValues: 125 blocks, 8000 entries, 16000 bytes
+// The third block is the zero block.
+var idnaValues = [8000]uint16{
+	// Block 0x0, offset 0x0
+	0x00: 0x0080, 0x01: 0x0080, 0x02: 0x0080, 0x03: 0x0080, 0x04: 0x0080, 0x05: 0x0080,
+	0x06: 0x0080, 0x07: 0x0080, 0x08: 0x0080, 0x09: 0x0080, 0x0a: 0x0080, 0x0b: 0x0080,
+	0x0c: 0x0080, 0x0d: 0x0080, 0x0e: 0x0080, 0x0f: 0x0080, 0x10: 0x0080, 0x11: 0x0080,
+	0x12: 0x0080, 0x13: 0x0080, 0x14: 0x0080, 0x15: 0x0080, 0x16: 0x0080, 0x17: 0x0080,
+	0x18: 0x0080, 0x19: 0x0080, 0x1a: 0x0080, 0x1b: 0x0080, 0x1c: 0x0080, 0x1d: 0x0080,
+	0x1e: 0x0080, 0x1f: 0x0080, 0x20: 0x0080, 0x21: 0x0080, 0x22: 0x0080, 0x23: 0x0080,
+	0x24: 0x0080, 0x25: 0x0080, 0x26: 0x0080, 0x27: 0x0080, 0x28: 0x0080, 0x29: 0x0080,
+	0x2a: 0x0080, 0x2b: 0x0080, 0x2c: 0x0080, 0x2d: 0x0008, 0x2e: 0x0008, 0x2f: 0x0080,
+	0x30: 0x0008, 0x31: 0x0008, 0x32: 0x0008, 0x33: 0x0008, 0x34: 0x0008, 0x35: 0x0008,
+	0x36: 0x0008, 0x37: 0x0008, 0x38: 0x0008, 0x39: 0x0008, 0x3a: 0x0080, 0x3b: 0x0080,
+	0x3c: 0x0080, 0x3d: 0x0080, 0x3e: 0x0080, 0x3f: 0x0080,
+	// Block 0x1, offset 0x40
+	0x40: 0x0080, 0x41: 0xe105, 0x42: 0xe105, 0x43: 0xe105, 0x44: 0xe105, 0x45: 0xe105,
+	0x46: 0xe105, 0x47: 0xe105, 0x48: 0xe105, 0x49: 0xe105, 0x4a: 0xe105, 0x4b: 0xe105,
+	0x4c: 0xe105, 0x4d: 0xe105, 0x4e: 0xe105, 0x4f: 0xe105, 0x50: 0xe105, 0x51: 0xe105,
+	0x52: 0xe105, 0x53: 0xe105, 0x54: 0xe105, 0x55: 0xe105, 0x56: 0xe105, 0x57: 0xe105,
+	0x58: 0xe105, 0x59: 0xe105, 0x5a: 0xe105, 0x5b: 0x0080, 0x5c: 0x0080, 0x5d: 0x0080,
+	0x5e: 0x0080, 0x5f: 0x0080, 0x60: 0x0080, 0x61: 0x0008, 0x62: 0x0008, 0x63: 0x0008,
+	0x64: 0x0008, 0x65: 0x0008, 0x66: 0x0008, 0x67: 0x0008, 0x68: 0x0008, 0x69: 0x0008,
+	0x6a: 0x0008, 0x6b: 0x0008, 0x6c: 0x0008, 0x6d: 0x0008, 0x6e: 0x0008, 0x6f: 0x0008,
+	0x70: 0x0008, 0x71: 0x0008, 0x72: 0x0008, 0x73: 0x0008, 0x74: 0x0008, 0x75: 0x0008,
+	0x76: 0x0008, 0x77: 0x0008, 0x78: 0x0008, 0x79: 0x0008, 0x7a: 0x0008, 0x7b: 0x0080,
+	0x7c: 0x0080, 0x7d: 0x0080, 0x7e: 0x0080, 0x7f: 0x0080,
+	// Block 0x2, offset 0x80
+	// Block 0x3, offset 0xc0
+	0xc0: 0x0040, 0xc1: 0x0040, 0xc2: 0x0040, 0xc3: 0x0040, 0xc4: 0x0040, 0xc5: 0x0040,
+	0xc6: 0x0040, 0xc7: 0x0040, 0xc8: 0x0040, 0xc9: 0x0040, 0xca: 0x0040, 0xcb: 0x0040,
+	0xcc: 0x0040, 0xcd: 0x0040, 0xce: 0x0040, 0xcf: 0x0040, 0xd0: 0x0040, 0xd1: 0x0040,
+	0xd2: 0x0040, 0xd3: 0x0040, 0xd4: 0x0040, 0xd5: 0x0040, 0xd6: 0x0040, 0xd7: 0x0040,
+	0xd8: 0x0040, 0xd9: 0x0040, 0xda: 0x0040, 0xdb: 0x0040, 0xdc: 0x0040, 0xdd: 0x0040,
+	0xde: 0x0040, 0xdf: 0x0040, 0xe0: 0x000a, 0xe1: 0x0018, 0xe2: 0x0018, 0xe3: 0x0018,
+	0xe4: 0x0018, 0xe5: 0x0018, 0xe6: 0x0018, 0xe7: 0x0018, 0xe8: 0x001a, 0xe9: 0x0018,
+	0xea: 0x0039, 0xeb: 0x0018, 0xec: 0x0018, 0xed: 0x03c0, 0xee: 0x0018, 0xef: 0x004a,
+	0xf0: 0x0018, 0xf1: 0x0018, 0xf2: 0x0069, 0xf3: 0x0079, 0xf4: 0x008a, 0xf5: 0x0005,
+	0xf6: 0x0018, 0xf7: 0x0008, 0xf8: 0x00aa, 0xf9: 0x00c9, 0xfa: 0x00d9, 0xfb: 0x0018,
+	0xfc: 0x00e9, 0xfd: 0x0119, 0xfe: 0x0149, 0xff: 0x0018,
+	// Block 0x4, offset 0x100
+	0x100: 0xe00d, 0x101: 0x0008, 0x102: 0xe00d, 0x103: 0x0008, 0x104: 0xe00d, 0x105: 0x0008,
+	0x106: 0xe00d, 0x107: 0x0008, 0x108: 0xe00d, 0x109: 0x0008, 0x10a: 0xe00d, 0x10b: 0x0008,
+	0x10c: 0xe00d, 0x10d: 0x0008, 0x10e: 0xe00d, 0x10f: 0x0008, 0x110: 0xe00d, 0x111: 0x0008,
+	0x112: 0xe00d, 0x113: 0x0008, 0x114: 0xe00d, 0x115: 0x0008, 0x116: 0xe00d, 0x117: 0x0008,
+	0x118: 0xe00d, 0x119: 0x0008, 0x11a: 0xe00d, 0x11b: 0x0008, 0x11c: 0xe00d, 0x11d: 0x0008,
+	0x11e: 0xe00d, 0x11f: 0x0008, 0x120: 0xe00d, 0x121: 0x0008, 0x122: 0xe00d, 0x123: 0x0008,
+	0x124: 0xe00d, 0x125: 0x0008, 0x126: 0xe00d, 0x127: 0x0008, 0x128: 0xe00d, 0x129: 0x0008,
+	0x12a: 0xe00d, 0x12b: 0x0008, 0x12c: 0xe00d, 0x12d: 0x0008, 0x12e: 0xe00d, 0x12f: 0x0008,
+	0x130: 0x0179, 0x131: 0x0008, 0x132: 0x0035, 0x133: 0x004d, 0x134: 0xe00d, 0x135: 0x0008,
+	0x136: 0xe00d, 0x137: 0x0008, 0x138: 0x0008, 0x139: 0xe01d, 0x13a: 0x0008, 0x13b: 0xe03d,
+	0x13c: 0x0008, 0x13d: 0xe01d, 0x13e: 0x0008, 0x13f: 0x0199,
+	// Block 0x5, offset 0x140
+	0x140: 0x0199, 0x141: 0xe01d, 0x142: 0x0008, 0x143: 0xe03d, 0x144: 0x0008, 0x145: 0xe01d,
+	0x146: 0x0008, 0x147: 0xe07d, 0x148: 0x0008, 0x149: 0x01b9, 0x14a: 0xe00d, 0x14b: 0x0008,
+	0x14c: 0xe00d, 0x14d: 0x0008, 0x14e: 0xe00d, 0x14f: 0x0008, 0x150: 0xe00d, 0x151: 0x0008,
+	0x152: 0xe00d, 0x153: 0x0008, 0x154: 0xe00d, 0x155: 0x0008, 0x156: 0xe00d, 0x157: 0x0008,
+	0x158: 0xe00d, 0x159: 0x0008, 0x15a: 0xe00d, 0x15b: 0x0008, 0x15c: 0xe00d, 0x15d: 0x0008,
+	0x15e: 0xe00d, 0x15f: 0x0008, 0x160: 0xe00d, 0x161: 0x0008, 0x162: 0xe00d, 0x163: 0x0008,
+	0x164: 0xe00d, 0x165: 0x0008, 0x166: 0xe00d, 0x167: 0x0008, 0x168: 0xe00d, 0x169: 0x0008,
+	0x16a: 0xe00d, 0x16b: 0x0008, 0x16c: 0xe00d, 0x16d: 0x0008, 0x16e: 0xe00d, 0x16f: 0x0008,
+	0x170: 0xe00d, 0x171: 0x0008, 0x172: 0xe00d, 0x173: 0x0008, 0x174: 0xe00d, 0x175: 0x0008,
+	0x176: 0xe00d, 0x177: 0x0008, 0x178: 0x0065, 0x179: 0xe01d, 0x17a: 0x0008, 0x17b: 0xe03d,
+	0x17c: 0x0008, 0x17d: 0xe01d, 0x17e: 0x0008, 0x17f: 0x01d9,
+	// Block 0x6, offset 0x180
+	0x180: 0x0008, 0x181: 0x007d, 0x182: 0xe00d, 0x183: 0x0008, 0x184: 0xe00d, 0x185: 0x0008,
+	0x186: 0x007d, 0x187: 0xe07d, 0x188: 0x0008, 0x189: 0x0095, 0x18a: 0x00ad, 0x18b: 0xe03d,
+	0x18c: 0x0008, 0x18d: 0x0008, 0x18e: 0x00c5, 0x18f: 0x00dd, 0x190: 0x00f5, 0x191: 0xe01d,
+	0x192: 0x0008, 0x193: 0x010d, 0x194: 0x0125, 0x195: 0x0008, 0x196: 0x013d, 0x197: 0x013d,
+	0x198: 0xe00d, 0x199: 0x0008, 0x19a: 0x0008, 0x19b: 0x0008, 0x19c: 0x010d, 0x19d: 0x0155,
+	0x19e: 0x0008, 0x19f: 0x016d, 0x1a0: 0xe00d, 0x1a1: 0x0008, 0x1a2: 0xe00d, 0x1a3: 0x0008,
+	0x1a4: 0xe00d, 0x1a5: 0x0008, 0x1a6: 0x0185, 0x1a7: 0xe07d, 0x1a8: 0x0008, 0x1a9: 0x019d,
+	0x1aa: 0x0008, 0x1ab: 0x0008, 0x1ac: 0xe00d, 0x1ad: 0x0008, 0x1ae: 0x0185, 0x1af: 0xe0fd,
+	0x1b0: 0x0008, 0x1b1: 0x01b5, 0x1b2: 0x01cd, 0x1b3: 0xe03d, 0x1b4: 0x0008, 0x1b5: 0xe01d,
+	0x1b6: 0x0008, 0x1b7: 0x01e5, 0x1b8: 0xe00d, 0x1b9: 0x0008, 0x1ba: 0x0008, 0x1bb: 0x0008,
+	0x1bc: 0xe00d, 0x1bd: 0x0008, 0x1be: 0x0008, 0x1bf: 0x0008,
+	// Block 0x7, offset 0x1c0
+	0x1c0: 0x0008, 0x1c1: 0x0008, 0x1c2: 0x0008, 0x1c3: 0x0008, 0x1c4: 0x01e9, 0x1c5: 0x01e9,
+	0x1c6: 0x01e9, 0x1c7: 0x01fd, 0x1c8: 0x0215, 0x1c9: 0x022d, 0x1ca: 0x0245, 0x1cb: 0x025d,
+	0x1cc: 0x0275, 0x1cd: 0xe01d, 0x1ce: 0x0008, 0x1cf: 0xe0fd, 0x1d0: 0x0008, 0x1d1: 0xe01d,
+	0x1d2: 0x0008, 0x1d3: 0xe03d, 0x1d4: 0x0008, 0x1d5: 0xe01d, 0x1d6: 0x0008, 0x1d7: 0xe07d,
+	0x1d8: 0x0008, 0x1d9: 0xe01d, 0x1da: 0x0008, 0x1db: 0xe03d, 0x1dc: 0x0008, 0x1dd: 0x0008,
+	0x1de: 0xe00d, 0x1df: 0x0008, 0x1e0: 0xe00d, 0x1e1: 0x0008, 0x1e2: 0xe00d, 0x1e3: 0x0008,
+	0x1e4: 0xe00d, 0x1e5: 0x0008, 0x1e6: 0xe00d, 0x1e7: 0x0008, 0x1e8: 0xe00d, 0x1e9: 0x0008,
+	0x1ea: 0xe00d, 0x1eb: 0x0008, 0x1ec: 0xe00d, 0x1ed: 0x0008, 0x1ee: 0xe00d, 0x1ef: 0x0008,
+	0x1f0: 0x0008, 0x1f1: 0x028d, 0x1f2: 0x02a5, 0x1f3: 0x02bd, 0x1f4: 0xe00d, 0x1f5: 0x0008,
+	0x1f6: 0x02d5, 0x1f7: 0x02ed, 0x1f8: 0xe00d, 0x1f9: 0x0008, 0x1fa: 0xe00d, 0x1fb: 0x0008,
+	0x1fc: 0xe00d, 0x1fd: 0x0008, 0x1fe: 0xe00d, 0x1ff: 0x0008,
+	// Block 0x8, offset 0x200
+	0x200: 0xe00d, 0x201: 0x0008, 0x202: 0xe00d, 0x203: 0x0008, 0x204: 0xe00d, 0x205: 0x0008,
+	0x206: 0xe00d, 0x207: 0x0008, 0x208: 0xe00d, 0x209: 0x0008, 0x20a: 0xe00d, 0x20b: 0x0008,
+	0x20c: 0xe00d, 0x20d: 0x0008, 0x20e: 0xe00d, 0x20f: 0x0008, 0x210: 0xe00d, 0x211: 0x0008,
+	0x212: 0xe00d, 0x213: 0x0008, 0x214: 0xe00d, 0x215: 0x0008, 0x216: 0xe00d, 0x217: 0x0008,
+	0x218: 0xe00d, 0x219: 0x0008, 0x21a: 0xe00d, 0x21b: 0x0008, 0x21c: 0xe00d, 0x21d: 0x0008,
+	0x21e: 0xe00d, 0x21f: 0x0008, 0x220: 0x0305, 0x221: 0x0008, 0x222: 0xe00d, 0x223: 0x0008,
+	0x224: 0xe00d, 0x225: 0x0008, 0x226: 0xe00d, 0x227: 0x0008, 0x228: 0xe00d, 0x229: 0x0008,
+	0x22a: 0xe00d, 0x22b: 0x0008, 0x22c: 0xe00d, 0x22d: 0x0008, 0x22e: 0xe00d, 0x22f: 0x0008,
+	0x230: 0xe00d, 0x231: 0x0008, 0x232: 0xe00d, 0x233: 0x0008, 0x234: 0x0008, 0x235: 0x0008,
+	0x236: 0x0008, 0x237: 0x0008, 0x238: 0x0008, 0x239: 0x0008, 0x23a: 0x0209, 0x23b: 0xe03d,
+	0x23c: 0x0008, 0x23d: 0x031d, 0x23e: 0x0229, 0x23f: 0x0008,
+	// Block 0x9, offset 0x240
+	0x240: 0x0008, 0x241: 0x0008, 0x242: 0x0018, 0x243: 0x0018, 0x244: 0x0018, 0x245: 0x0018,
+	0x246: 0x0008, 0x247: 0x0008, 0x248: 0x0008, 0x249: 0x0008, 0x24a: 0x0008, 0x24b: 0x0008,
+	0x24c: 0x0008, 0x24d: 0x0008, 0x24e: 0x0008, 0x24f: 0x0008, 0x250: 0x0008, 0x251: 0x0008,
+	0x252: 0x0018, 0x253: 0x0018, 0x254: 0x0018, 0x255: 0x0018, 0x256: 0x0018, 0x257: 0x0018,
+	0x258: 0x029a, 0x259: 0x02ba, 0x25a: 0x02da, 0x25b: 0x02fa, 0x25c: 0x031a, 0x25d: 0x033a,
+	0x25e: 0x0018, 0x25f: 0x0018, 0x260: 0x03ad, 0x261: 0x0359, 0x262: 0x01d9, 0x263: 0x0369,
+	0x264: 0x03c5, 0x265: 0x0018, 0x266: 0x0018, 0x267: 0x0018, 0x268: 0x0018, 0x269: 0x0018,
+	0x26a: 0x0018, 0x26b: 0x0018, 0x26c: 0x0008, 0x26d: 0x0018, 0x26e: 0x0008, 0x26f: 0x0018,
+	0x270: 0x0018, 0x271: 0x0018, 0x272: 0x0018, 0x273: 0x0018, 0x274: 0x0018, 0x275: 0x0018,
+	0x276: 0x0018, 0x277: 0x0018, 0x278: 0x0018, 0x279: 0x0018, 0x27a: 0x0018, 0x27b: 0x0018,
+	0x27c: 0x0018, 0x27d: 0x0018, 0x27e: 0x0018, 0x27f: 0x0018,
+	// Block 0xa, offset 0x280
+	0x280: 0x03dd, 0x281: 0x03dd, 0x282: 0x1308, 0x283: 0x03f5, 0x284: 0x0379, 0x285: 0x040d,
+	0x286: 0x1308, 0x287: 0x1308, 0x288: 0x1308, 0x289: 0x1308, 0x28a: 0x1308, 0x28b: 0x1308,
+	0x28c: 0x1308, 0x28d: 0x1308, 0x28e: 0x1308, 0x28f: 0x13c0, 0x290: 0x1308, 0x291: 0x1308,
+	0x292: 0x1308, 0x293: 0x1308, 0x294: 0x1308, 0x295: 0x1308, 0x296: 0x1308, 0x297: 0x1308,
+	0x298: 0x1308, 0x299: 0x1308, 0x29a: 0x1308, 0x29b: 0x1308, 0x29c: 0x1308, 0x29d: 0x1308,
+	0x29e: 0x1308, 0x29f: 0x1308, 0x2a0: 0x1308, 0x2a1: 0x1308, 0x2a2: 0x1308, 0x2a3: 0x1308,
+	0x2a4: 0x1308, 0x2a5: 0x1308, 0x2a6: 0x1308, 0x2a7: 0x1308, 0x2a8: 0x1308, 0x2a9: 0x1308,
+	0x2aa: 0x1308, 0x2ab: 0x1308, 0x2ac: 0x1308, 0x2ad: 0x1308, 0x2ae: 0x1308, 0x2af: 0x1308,
+	0x2b0: 0xe00d, 0x2b1: 0x0008, 0x2b2: 0xe00d, 0x2b3: 0x0008, 0x2b4: 0x0425, 0x2b5: 0x0008,
+	0x2b6: 0xe00d, 0x2b7: 0x0008, 0x2b8: 0x0040, 0x2b9: 0x0040, 0x2ba: 0x03a2, 0x2bb: 0x0008,
+	0x2bc: 0x0008, 0x2bd: 0x0008, 0x2be: 0x03c2, 0x2bf: 0x043d,
+	// Block 0xb, offset 0x2c0
+	0x2c0: 0x0040, 0x2c1: 0x0040, 0x2c2: 0x0040, 0x2c3: 0x0040, 0x2c4: 0x008a, 0x2c5: 0x03d2,
+	0x2c6: 0xe155, 0x2c7: 0x0455, 0x2c8: 0xe12d, 0x2c9: 0xe13d, 0x2ca: 0xe12d, 0x2cb: 0x0040,
+	0x2cc: 0x03dd, 0x2cd: 0x0040, 0x2ce: 0x046d, 0x2cf: 0x0485, 0x2d0: 0x0008, 0x2d1: 0xe105,
+	0x2d2: 0xe105, 0x2d3: 0xe105, 0x2d4: 0xe105, 0x2d5: 0xe105, 0x2d6: 0xe105, 0x2d7: 0xe105,
+	0x2d8: 0xe105, 0x2d9: 0xe105, 0x2da: 0xe105, 0x2db: 0xe105, 0x2dc: 0xe105, 0x2dd: 0xe105,
+	0x2de: 0xe105, 0x2df: 0xe105, 0x2e0: 0x049d, 0x2e1: 0x049d, 0x2e2: 0x0040, 0x2e3: 0x049d,
+	0x2e4: 0x049d, 0x2e5: 0x049d, 0x2e6: 0x049d, 0x2e7: 0x049d, 0x2e8: 0x049d, 0x2e9: 0x049d,
+	0x2ea: 0x049d, 0x2eb: 0x049d, 0x2ec: 0x0008, 0x2ed: 0x0008, 0x2ee: 0x0008, 0x2ef: 0x0008,
+	0x2f0: 0x0008, 0x2f1: 0x0008, 0x2f2: 0x0008, 0x2f3: 0x0008, 0x2f4: 0x0008, 0x2f5: 0x0008,
+	0x2f6: 0x0008, 0x2f7: 0x0008, 0x2f8: 0x0008, 0x2f9: 0x0008, 0x2fa: 0x0008, 0x2fb: 0x0008,
+	0x2fc: 0x0008, 0x2fd: 0x0008, 0x2fe: 0x0008, 0x2ff: 0x0008,
+	// Block 0xc, offset 0x300
+	0x300: 0x0008, 0x301: 0x0008, 0x302: 0xe00f, 0x303: 0x0008, 0x304: 0x0008, 0x305: 0x0008,
+	0x306: 0x0008, 0x307: 0x0008, 0x308: 0x0008, 0x309: 0x0008, 0x30a: 0x0008, 0x30b: 0x0008,
+	0x30c: 0x0008, 0x30d: 0x0008, 0x30e: 0x0008, 0x30f: 0xe0c5, 0x310: 0x04b5, 0x311: 0x04cd,
+	0x312: 0xe0bd, 0x313: 0xe0f5, 0x314: 0xe0fd, 0x315: 0xe09d, 0x316: 0xe0b5, 0x317: 0x0008,
+	0x318: 0xe00d, 0x319: 0x0008, 0x31a: 0xe00d, 0x31b: 0x0008, 0x31c: 0xe00d, 0x31d: 0x0008,
+	0x31e: 0xe00d, 0x31f: 0x0008, 0x320: 0xe00d, 0x321: 0x0008, 0x322: 0xe00d, 0x323: 0x0008,
+	0x324: 0xe00d, 0x325: 0x0008, 0x326: 0xe00d, 0x327: 0x0008, 0x328: 0xe00d, 0x329: 0x0008,
+	0x32a: 0xe00d, 0x32b: 0x0008, 0x32c: 0xe00d, 0x32d: 0x0008, 0x32e: 0xe00d, 0x32f: 0x0008,
+	0x330: 0x04e5, 0x331: 0xe185, 0x332: 0xe18d, 0x333: 0x0008, 0x334: 0x04fd, 0x335: 0x03dd,
+	0x336: 0x0018, 0x337: 0xe07d, 0x338: 0x0008, 0x339: 0xe1d5, 0x33a: 0xe00d, 0x33b: 0x0008,
+	0x33c: 0x0008, 0x33d: 0x0515, 0x33e: 0x052d, 0x33f: 0x052d,
+	// Block 0xd, offset 0x340
+	0x340: 0x0008, 0x341: 0x0008, 0x342: 0x0008, 0x343: 0x0008, 0x344: 0x0008, 0x345: 0x0008,
+	0x346: 0x0008, 0x347: 0x0008, 0x348: 0x0008, 0x349: 0x0008, 0x34a: 0x0008, 0x34b: 0x0008,
+	0x34c: 0x0008, 0x34d: 0x0008, 0x34e: 0x0008, 0x34f: 0x0008, 0x350: 0x0008, 0x351: 0x0008,
+	0x352: 0x0008, 0x353: 0x0008, 0x354: 0x0008, 0x355: 0x0008, 0x356: 0x0008, 0x357: 0x0008,
+	0x358: 0x0008, 0x359: 0x0008, 0x35a: 0x0008, 0x35b: 0x0008, 0x35c: 0x0008, 0x35d: 0x0008,
+	0x35e: 0x0008, 0x35f: 0x0008, 0x360: 0xe00d, 0x361: 0x0008, 0x362: 0xe00d, 0x363: 0x0008,
+	0x364: 0xe00d, 0x365: 0x0008, 0x366: 0xe00d, 0x367: 0x0008, 0x368: 0xe00d, 0x369: 0x0008,
+	0x36a: 0xe00d, 0x36b: 0x0008, 0x36c: 0xe00d, 0x36d: 0x0008, 0x36e: 0xe00d, 0x36f: 0x0008,
+	0x370: 0xe00d, 0x371: 0x0008, 0x372: 0xe00d, 0x373: 0x0008, 0x374: 0xe00d, 0x375: 0x0008,
+	0x376: 0xe00d, 0x377: 0x0008, 0x378: 0xe00d, 0x379: 0x0008, 0x37a: 0xe00d, 0x37b: 0x0008,
+	0x37c: 0xe00d, 0x37d: 0x0008, 0x37e: 0xe00d, 0x37f: 0x0008,
+	// Block 0xe, offset 0x380
+	0x380: 0xe00d, 0x381: 0x0008, 0x382: 0x0018, 0x383: 0x1308, 0x384: 0x1308, 0x385: 0x1308,
+	0x386: 0x1308, 0x387: 0x1308, 0x388: 0x1318, 0x389: 0x1318, 0x38a: 0xe00d, 0x38b: 0x0008,
+	0x38c: 0xe00d, 0x38d: 0x0008, 0x38e: 0xe00d, 0x38f: 0x0008, 0x390: 0xe00d, 0x391: 0x0008,
+	0x392: 0xe00d, 0x393: 0x0008, 0x394: 0xe00d, 0x395: 0x0008, 0x396: 0xe00d, 0x397: 0x0008,
+	0x398: 0xe00d, 0x399: 0x0008, 0x39a: 0xe00d, 0x39b: 0x0008, 0x39c: 0xe00d, 0x39d: 0x0008,
+	0x39e: 0xe00d, 0x39f: 0x0008, 0x3a0: 0xe00d, 0x3a1: 0x0008, 0x3a2: 0xe00d, 0x3a3: 0x0008,
+	0x3a4: 0xe00d, 0x3a5: 0x0008, 0x3a6: 0xe00d, 0x3a7: 0x0008, 0x3a8: 0xe00d, 0x3a9: 0x0008,
+	0x3aa: 0xe00d, 0x3ab: 0x0008, 0x3ac: 0xe00d, 0x3ad: 0x0008, 0x3ae: 0xe00d, 0x3af: 0x0008,
+	0x3b0: 0xe00d, 0x3b1: 0x0008, 0x3b2: 0xe00d, 0x3b3: 0x0008, 0x3b4: 0xe00d, 0x3b5: 0x0008,
+	0x3b6: 0xe00d, 0x3b7: 0x0008, 0x3b8: 0xe00d, 0x3b9: 0x0008, 0x3ba: 0xe00d, 0x3bb: 0x0008,
+	0x3bc: 0xe00d, 0x3bd: 0x0008, 0x3be: 0xe00d, 0x3bf: 0x0008,
+	// Block 0xf, offset 0x3c0
+	0x3c0: 0x0040, 0x3c1: 0xe01d, 0x3c2: 0x0008, 0x3c3: 0xe03d, 0x3c4: 0x0008, 0x3c5: 0xe01d,
+	0x3c6: 0x0008, 0x3c7: 0xe07d, 0x3c8: 0x0008, 0x3c9: 0xe01d, 0x3ca: 0x0008, 0x3cb: 0xe03d,
+	0x3cc: 0x0008, 0x3cd: 0xe01d, 0x3ce: 0x0008, 0x3cf: 0x0008, 0x3d0: 0xe00d, 0x3d1: 0x0008,
+	0x3d2: 0xe00d, 0x3d3: 0x0008, 0x3d4: 0xe00d, 0x3d5: 0x0008, 0x3d6: 0xe00d, 0x3d7: 0x0008,
+	0x3d8: 0xe00d, 0x3d9: 0x0008, 0x3da: 0xe00d, 0x3db: 0x0008, 0x3dc: 0xe00d, 0x3dd: 0x0008,
+	0x3de: 0xe00d, 0x3df: 0x0008, 0x3e0: 0xe00d, 0x3e1: 0x0008, 0x3e2: 0xe00d, 0x3e3: 0x0008,
+	0x3e4: 0xe00d, 0x3e5: 0x0008, 0x3e6: 0xe00d, 0x3e7: 0x0008, 0x3e8: 0xe00d, 0x3e9: 0x0008,
+	0x3ea: 0xe00d, 0x3eb: 0x0008, 0x3ec: 0xe00d, 0x3ed: 0x0008, 0x3ee: 0xe00d, 0x3ef: 0x0008,
+	0x3f0: 0xe00d, 0x3f1: 0x0008, 0x3f2: 0xe00d, 0x3f3: 0x0008, 0x3f4: 0xe00d, 0x3f5: 0x0008,
+	0x3f6: 0xe00d, 0x3f7: 0x0008, 0x3f8: 0xe00d, 0x3f9: 0x0008, 0x3fa: 0xe00d, 0x3fb: 0x0008,
+	0x3fc: 0xe00d, 0x3fd: 0x0008, 0x3fe: 0xe00d, 0x3ff: 0x0008,
+	// Block 0x10, offset 0x400
+	0x400: 0xe00d, 0x401: 0x0008, 0x402: 0xe00d, 0x403: 0x0008, 0x404: 0xe00d, 0x405: 0x0008,
+	0x406: 0xe00d, 0x407: 0x0008, 0x408: 0xe00d, 0x409: 0x0008, 0x40a: 0xe00d, 0x40b: 0x0008,
+	0x40c: 0xe00d, 0x40d: 0x0008, 0x40e: 0xe00d, 0x40f: 0x0008, 0x410: 0xe00d, 0x411: 0x0008,
+	0x412: 0xe00d, 0x413: 0x0008, 0x414: 0xe00d, 0x415: 0x0008, 0x416: 0xe00d, 0x417: 0x0008,
+	0x418: 0xe00d, 0x419: 0x0008, 0x41a: 0xe00d, 0x41b: 0x0008, 0x41c: 0xe00d, 0x41d: 0x0008,
+	0x41e: 0xe00d, 0x41f: 0x0008, 0x420: 0xe00d, 0x421: 0x0008, 0x422: 0xe00d, 0x423: 0x0008,
+	0x424: 0xe00d, 0x425: 0x0008, 0x426: 0xe00d, 0x427: 0x0008, 0x428: 0xe00d, 0x429: 0x0008,
+	0x42a: 0xe00d, 0x42b: 0x0008, 0x42c: 0xe00d, 0x42d: 0x0008, 0x42e: 0xe00d, 0x42f: 0x0008,
+	0x430: 0x0040, 0x431: 0x03f5, 0x432: 0x03f5, 0x433: 0x03f5, 0x434: 0x03f5, 0x435: 0x03f5,
+	0x436: 0x03f5, 0x437: 0x03f5, 0x438: 0x03f5, 0x439: 0x03f5, 0x43a: 0x03f5, 0x43b: 0x03f5,
+	0x43c: 0x03f5, 0x43d: 0x03f5, 0x43e: 0x03f5, 0x43f: 0x03f5,
+	// Block 0x11, offset 0x440
+	0x440: 0x0040, 0x441: 0x0040, 0x442: 0x0040, 0x443: 0x0040, 0x444: 0x0040, 0x445: 0x0040,
+	0x446: 0x0018, 0x447: 0x0018, 0x448: 0x0018, 0x449: 0x0018, 0x44a: 0x0018, 0x44b: 0x0018,
+	0x44c: 0x0018, 0x44d: 0x0018, 0x44e: 0x0018, 0x44f: 0x0018, 0x450: 0x1308, 0x451: 0x1308,
+	0x452: 0x1308, 0x453: 0x1308, 0x454: 0x1308, 0x455: 0x1308, 0x456: 0x1308, 0x457: 0x1308,
+	0x458: 0x1308, 0x459: 0x1308, 0x45a: 0x1308, 0x45b: 0x0018, 0x45c: 0x0340, 0x45d: 0x0040,
+	0x45e: 0x0018, 0x45f: 0x0018, 0x460: 0x0208, 0x461: 0x0008, 0x462: 0x0408, 0x463: 0x0408,
+	0x464: 0x0408, 0x465: 0x0408, 0x466: 0x0208, 0x467: 0x0408, 0x468: 0x0208, 0x469: 0x0408,
+	0x46a: 0x0208, 0x46b: 0x0208, 0x46c: 0x0208, 0x46d: 0x0208, 0x46e: 0x0208, 0x46f: 0x0408,
+	0x470: 0x0408, 0x471: 0x0408, 0x472: 0x0408, 0x473: 0x0208, 0x474: 0x0208, 0x475: 0x0208,
+	0x476: 0x0208, 0x477: 0x0208, 0x478: 0x0208, 0x479: 0x0208, 0x47a: 0x0208, 0x47b: 0x0208,
+	0x47c: 0x0208, 0x47d: 0x0208, 0x47e: 0x0208, 0x47f: 0x0208,
+	// Block 0x12, offset 0x480
+	0x480: 0x0408, 0x481: 0x0208, 0x482: 0x0208, 0x483: 0x0408, 0x484: 0x0408, 0x485: 0x0408,
+	0x486: 0x0408, 0x487: 0x0408, 0x488: 0x0408, 0x489: 0x0408, 0x48a: 0x0408, 0x48b: 0x0408,
+	0x48c: 0x0208, 0x48d: 0x0408, 0x48e: 0x0208, 0x48f: 0x0408, 0x490: 0x0208, 0x491: 0x0208,
+	0x492: 0x0408, 0x493: 0x0408, 0x494: 0x0018, 0x495: 0x0408, 0x496: 0x1308, 0x497: 0x1308,
+	0x498: 0x1308, 0x499: 0x1308, 0x49a: 0x1308, 0x49b: 0x1308, 0x49c: 0x1308, 0x49d: 0x0040,
+	0x49e: 0x0018, 0x49f: 0x1308, 0x4a0: 0x1308, 0x4a1: 0x1308, 0x4a2: 0x1308, 0x4a3: 0x1308,
+	0x4a4: 0x1308, 0x4a5: 0x0008, 0x4a6: 0x0008, 0x4a7: 0x1308, 0x4a8: 0x1308, 0x4a9: 0x0018,
+	0x4aa: 0x1308, 0x4ab: 0x1308, 0x4ac: 0x1308, 0x4ad: 0x1308, 0x4ae: 0x0408, 0x4af: 0x0408,
+	0x4b0: 0x0008, 0x4b1: 0x0008, 0x4b2: 0x0008, 0x4b3: 0x0008, 0x4b4: 0x0008, 0x4b5: 0x0008,
+	0x4b6: 0x0008, 0x4b7: 0x0008, 0x4b8: 0x0008, 0x4b9: 0x0008, 0x4ba: 0x0208, 0x4bb: 0x0208,
+	0x4bc: 0x0208, 0x4bd: 0x0008, 0x4be: 0x0008, 0x4bf: 0x0208,
+	// Block 0x13, offset 0x4c0
+	0x4c0: 0x0018, 0x4c1: 0x0018, 0x4c2: 0x0018, 0x4c3: 0x0018, 0x4c4: 0x0018, 0x4c5: 0x0018,
+	0x4c6: 0x0018, 0x4c7: 0x0018, 0x4c8: 0x0018, 0x4c9: 0x0018, 0x4ca: 0x0018, 0x4cb: 0x0018,
+	0x4cc: 0x0018, 0x4cd: 0x0018, 0x4ce: 0x0040, 0x4cf: 0x0340, 0x4d0: 0x0408, 0x4d1: 0x1308,
+	0x4d2: 0x0208, 0x4d3: 0x0208, 0x4d4: 0x0208, 0x4d5: 0x0408, 0x4d6: 0x0408, 0x4d7: 0x0408,
+	0x4d8: 0x0408, 0x4d9: 0x0408, 0x4da: 0x0208, 0x4db: 0x0208, 0x4dc: 0x0208, 0x4dd: 0x0208,
+	0x4de: 0x0408, 0x4df: 0x0208, 0x4e0: 0x0208, 0x4e1: 0x0208, 0x4e2: 0x0208, 0x4e3: 0x0208,
+	0x4e4: 0x0208, 0x4e5: 0x0208, 0x4e6: 0x0208, 0x4e7: 0x0208, 0x4e8: 0x0408, 0x4e9: 0x0208,
+	0x4ea: 0x0408, 0x4eb: 0x0208, 0x4ec: 0x0408, 0x4ed: 0x0208, 0x4ee: 0x0208, 0x4ef: 0x0408,
+	0x4f0: 0x1308, 0x4f1: 0x1308, 0x4f2: 0x1308, 0x4f3: 0x1308, 0x4f4: 0x1308, 0x4f5: 0x1308,
+	0x4f6: 0x1308, 0x4f7: 0x1308, 0x4f8: 0x1308, 0x4f9: 0x1308, 0x4fa: 0x1308, 0x4fb: 0x1308,
+	0x4fc: 0x1308, 0x4fd: 0x1308, 0x4fe: 0x1308, 0x4ff: 0x1308,
+	// Block 0x14, offset 0x500
+	0x500: 0x1008, 0x501: 0x1308, 0x502: 0x1308, 0x503: 0x1308, 0x504: 0x1308, 0x505: 0x1308,
+	0x506: 0x1308, 0x507: 0x1308, 0x508: 0x1308, 0x509: 0x1008, 0x50a: 0x1008, 0x50b: 0x1008,
+	0x50c: 0x1008, 0x50d: 0x1b08, 0x50e: 0x1008, 0x50f: 0x1008, 0x510: 0x0008, 0x511: 0x1308,
+	0x512: 0x1308, 0x513: 0x1308, 0x514: 0x1308, 0x515: 0x1308, 0x516: 0x1308, 0x517: 0x1308,
+	0x518: 0x04c9, 0x519: 0x0501, 0x51a: 0x0539, 0x51b: 0x0571, 0x51c: 0x05a9, 0x51d: 0x05e1,
+	0x51e: 0x0619, 0x51f: 0x0651, 0x520: 0x0008, 0x521: 0x0008, 0x522: 0x1308, 0x523: 0x1308,
+	0x524: 0x0018, 0x525: 0x0018, 0x526: 0x0008, 0x527: 0x0008, 0x528: 0x0008, 0x529: 0x0008,
+	0x52a: 0x0008, 0x52b: 0x0008, 0x52c: 0x0008, 0x52d: 0x0008, 0x52e: 0x0008, 0x52f: 0x0008,
+	0x530: 0x0018, 0x531: 0x0008, 0x532: 0x0008, 0x533: 0x0008, 0x534: 0x0008, 0x535: 0x0008,
+	0x536: 0x0008, 0x537: 0x0008, 0x538: 0x0008, 0x539: 0x0008, 0x53a: 0x0008, 0x53b: 0x0008,
+	0x53c: 0x0008, 0x53d: 0x0008, 0x53e: 0x0008, 0x53f: 0x0008,
+	// Block 0x15, offset 0x540
+	0x540: 0x0008, 0x541: 0x1308, 0x542: 0x1008, 0x543: 0x1008, 0x544: 0x0040, 0x545: 0x0008,
+	0x546: 0x0008, 0x547: 0x0008, 0x548: 0x0008, 0x549: 0x0008, 0x54a: 0x0008, 0x54b: 0x0008,
+	0x54c: 0x0008, 0x54d: 0x0040, 0x54e: 0x0040, 0x54f: 0x0008, 0x550: 0x0008, 0x551: 0x0040,
+	0x552: 0x0040, 0x553: 0x0008, 0x554: 0x0008, 0x555: 0x0008, 0x556: 0x0008, 0x557: 0x0008,
+	0x558: 0x0008, 0x559: 0x0008, 0x55a: 0x0008, 0x55b: 0x0008, 0x55c: 0x0008, 0x55d: 0x0008,
+	0x55e: 0x0008, 0x55f: 0x0008, 0x560: 0x0008, 0x561: 0x0008, 0x562: 0x0008, 0x563: 0x0008,
+	0x564: 0x0008, 0x565: 0x0008, 0x566: 0x0008, 0x567: 0x0008, 0x568: 0x0008, 0x569: 0x0040,
+	0x56a: 0x0008, 0x56b: 0x0008, 0x56c: 0x0008, 0x56d: 0x0008, 0x56e: 0x0008, 0x56f: 0x0008,
+	0x570: 0x0008, 0x571: 0x0040, 0x572: 0x0008, 0x573: 0x0040, 0x574: 0x0040, 0x575: 0x0040,
+	0x576: 0x0008, 0x577: 0x0008, 0x578: 0x0008, 0x579: 0x0008, 0x57a: 0x0040, 0x57b: 0x0040,
+	0x57c: 0x1308, 0x57d: 0x0008, 0x57e: 0x1008, 0x57f: 0x1008,
+	// Block 0x16, offset 0x580
+	0x580: 0x1008, 0x581: 0x1308, 0x582: 0x1308, 0x583: 0x1308, 0x584: 0x1308, 0x585: 0x0040,
+	0x586: 0x0040, 0x587: 0x1008, 0x588: 0x1008, 0x589: 0x0040, 0x58a: 0x0040, 0x58b: 0x1008,
+	0x58c: 0x1008, 0x58d: 0x1b08, 0x58e: 0x0008, 0x58f: 0x0040, 0x590: 0x0040, 0x591: 0x0040,
+	0x592: 0x0040, 0x593: 0x0040, 0x594: 0x0040, 0x595: 0x0040, 0x596: 0x0040, 0x597: 0x1008,
+	0x598: 0x0040, 0x599: 0x0040, 0x59a: 0x0040, 0x59b: 0x0040, 0x59c: 0x0689, 0x59d: 0x06c1,
+	0x59e: 0x0040, 0x59f: 0x06f9, 0x5a0: 0x0008, 0x5a1: 0x0008, 0x5a2: 0x1308, 0x5a3: 0x1308,
+	0x5a4: 0x0040, 0x5a5: 0x0040, 0x5a6: 0x0008, 0x5a7: 0x0008, 0x5a8: 0x0008, 0x5a9: 0x0008,
+	0x5aa: 0x0008, 0x5ab: 0x0008, 0x5ac: 0x0008, 0x5ad: 0x0008, 0x5ae: 0x0008, 0x5af: 0x0008,
+	0x5b0: 0x0008, 0x5b1: 0x0008, 0x5b2: 0x0018, 0x5b3: 0x0018, 0x5b4: 0x0018, 0x5b5: 0x0018,
+	0x5b6: 0x0018, 0x5b7: 0x0018, 0x5b8: 0x0018, 0x5b9: 0x0018, 0x5ba: 0x0018, 0x5bb: 0x0018,
+	0x5bc: 0x0040, 0x5bd: 0x0040, 0x5be: 0x0040, 0x5bf: 0x0040,
+	// Block 0x17, offset 0x5c0
+	0x5c0: 0x0040, 0x5c1: 0x1308, 0x5c2: 0x1308, 0x5c3: 0x1008, 0x5c4: 0x0040, 0x5c5: 0x0008,
+	0x5c6: 0x0008, 0x5c7: 0x0008, 0x5c8: 0x0008, 0x5c9: 0x0008, 0x5ca: 0x0008, 0x5cb: 0x0040,
+	0x5cc: 0x0040, 0x5cd: 0x0040, 0x5ce: 0x0040, 0x5cf: 0x0008, 0x5d0: 0x0008, 0x5d1: 0x0040,
+	0x5d2: 0x0040, 0x5d3: 0x0008, 0x5d4: 0x0008, 0x5d5: 0x0008, 0x5d6: 0x0008, 0x5d7: 0x0008,
+	0x5d8: 0x0008, 0x5d9: 0x0008, 0x5da: 0x0008, 0x5db: 0x0008, 0x5dc: 0x0008, 0x5dd: 0x0008,
+	0x5de: 0x0008, 0x5df: 0x0008, 0x5e0: 0x0008, 0x5e1: 0x0008, 0x5e2: 0x0008, 0x5e3: 0x0008,
+	0x5e4: 0x0008, 0x5e5: 0x0008, 0x5e6: 0x0008, 0x5e7: 0x0008, 0x5e8: 0x0008, 0x5e9: 0x0040,
+	0x5ea: 0x0008, 0x5eb: 0x0008, 0x5ec: 0x0008, 0x5ed: 0x0008, 0x5ee: 0x0008, 0x5ef: 0x0008,
+	0x5f0: 0x0008, 0x5f1: 0x0040, 0x5f2: 0x0008, 0x5f3: 0x0731, 0x5f4: 0x0040, 0x5f5: 0x0008,
+	0x5f6: 0x0769, 0x5f7: 0x0040, 0x5f8: 0x0008, 0x5f9: 0x0008, 0x5fa: 0x0040, 0x5fb: 0x0040,
+	0x5fc: 0x1308, 0x5fd: 0x0040, 0x5fe: 0x1008, 0x5ff: 0x1008,
+	// Block 0x18, offset 0x600
+	0x600: 0x1008, 0x601: 0x1308, 0x602: 0x1308, 0x603: 0x0040, 0x604: 0x0040, 0x605: 0x0040,
+	0x606: 0x0040, 0x607: 0x1308, 0x608: 0x1308, 0x609: 0x0040, 0x60a: 0x0040, 0x60b: 0x1308,
+	0x60c: 0x1308, 0x60d: 0x1b08, 0x60e: 0x0040, 0x60f: 0x0040, 0x610: 0x0040, 0x611: 0x1308,
+	0x612: 0x0040, 0x613: 0x0040, 0x614: 0x0040, 0x615: 0x0040, 0x616: 0x0040, 0x617: 0x0040,
+	0x618: 0x0040, 0x619: 0x07a1, 0x61a: 0x07d9, 0x61b: 0x0811, 0x61c: 0x0008, 0x61d: 0x0040,
+	0x61e: 0x0849, 0x61f: 0x0040, 0x620: 0x0040, 0x621: 0x0040, 0x622: 0x0040, 0x623: 0x0040,
+	0x624: 0x0040, 0x625: 0x0040, 0x626: 0x0008, 0x627: 0x0008, 0x628: 0x0008, 0x629: 0x0008,
+	0x62a: 0x0008, 0x62b: 0x0008, 0x62c: 0x0008, 0x62d: 0x0008, 0x62e: 0x0008, 0x62f: 0x0008,
+	0x630: 0x1308, 0x631: 0x1308, 0x632: 0x0008, 0x633: 0x0008, 0x634: 0x0008, 0x635: 0x1308,
+	0x636: 0x0040, 0x637: 0x0040, 0x638: 0x0040, 0x639: 0x0040, 0x63a: 0x0040, 0x63b: 0x0040,
+	0x63c: 0x0040, 0x63d: 0x0040, 0x63e: 0x0040, 0x63f: 0x0040,
+	// Block 0x19, offset 0x640
+	0x640: 0x0040, 0x641: 0x1308, 0x642: 0x1308, 0x643: 0x1008, 0x644: 0x0040, 0x645: 0x0008,
+	0x646: 0x0008, 0x647: 0x0008, 0x648: 0x0008, 0x649: 0x0008, 0x64a: 0x0008, 0x64b: 0x0008,
+	0x64c: 0x0008, 0x64d: 0x0008, 0x64e: 0x0040, 0x64f: 0x0008, 0x650: 0x0008, 0x651: 0x0008,
+	0x652: 0x0040, 0x653: 0x0008, 0x654: 0x0008, 0x655: 0x0008, 0x656: 0x0008, 0x657: 0x0008,
+	0x658: 0x0008, 0x659: 0x0008, 0x65a: 0x0008, 0x65b: 0x0008, 0x65c: 0x0008, 0x65d: 0x0008,
+	0x65e: 0x0008, 0x65f: 0x0008, 0x660: 0x0008, 0x661: 0x0008, 0x662: 0x0008, 0x663: 0x0008,
+	0x664: 0x0008, 0x665: 0x0008, 0x666: 0x0008, 0x667: 0x0008, 0x668: 0x0008, 0x669: 0x0040,
+	0x66a: 0x0008, 0x66b: 0x0008, 0x66c: 0x0008, 0x66d: 0x0008, 0x66e: 0x0008, 0x66f: 0x0008,
+	0x670: 0x0008, 0x671: 0x0040, 0x672: 0x0008, 0x673: 0x0008, 0x674: 0x0040, 0x675: 0x0008,
+	0x676: 0x0008, 0x677: 0x0008, 0x678: 0x0008, 0x679: 0x0008, 0x67a: 0x0040, 0x67b: 0x0040,
+	0x67c: 0x1308, 0x67d: 0x0008, 0x67e: 0x1008, 0x67f: 0x1008,
+	// Block 0x1a, offset 0x680
+	0x680: 0x1008, 0x681: 0x1308, 0x682: 0x1308, 0x683: 0x1308, 0x684: 0x1308, 0x685: 0x1308,
+	0x686: 0x0040, 0x687: 0x1308, 0x688: 0x1308, 0x689: 0x1008, 0x68a: 0x0040, 0x68b: 0x1008,
+	0x68c: 0x1008, 0x68d: 0x1b08, 0x68e: 0x0040, 0x68f: 0x0040, 0x690: 0x0008, 0x691: 0x0040,
+	0x692: 0x0040, 0x693: 0x0040, 0x694: 0x0040, 0x695: 0x0040, 0x696: 0x0040, 0x697: 0x0040,
+	0x698: 0x0040, 0x699: 0x0040, 0x69a: 0x0040, 0x69b: 0x0040, 0x69c: 0x0040, 0x69d: 0x0040,
+	0x69e: 0x0040, 0x69f: 0x0040, 0x6a0: 0x0008, 0x6a1: 0x0008, 0x6a2: 0x1308, 0x6a3: 0x1308,
+	0x6a4: 0x0040, 0x6a5: 0x0040, 0x6a6: 0x0008, 0x6a7: 0x0008, 0x6a8: 0x0008, 0x6a9: 0x0008,
+	0x6aa: 0x0008, 0x6ab: 0x0008, 0x6ac: 0x0008, 0x6ad: 0x0008, 0x6ae: 0x0008, 0x6af: 0x0008,
+	0x6b0: 0x0018, 0x6b1: 0x0018, 0x6b2: 0x0040, 0x6b3: 0x0040, 0x6b4: 0x0040, 0x6b5: 0x0040,
+	0x6b6: 0x0040, 0x6b7: 0x0040, 0x6b8: 0x0040, 0x6b9: 0x0008, 0x6ba: 0x0040, 0x6bb: 0x0040,
+	0x6bc: 0x0040, 0x6bd: 0x0040, 0x6be: 0x0040, 0x6bf: 0x0040,
+	// Block 0x1b, offset 0x6c0
+	0x6c0: 0x0040, 0x6c1: 0x1308, 0x6c2: 0x1008, 0x6c3: 0x1008, 0x6c4: 0x0040, 0x6c5: 0x0008,
+	0x6c6: 0x0008, 0x6c7: 0x0008, 0x6c8: 0x0008, 0x6c9: 0x0008, 0x6ca: 0x0008, 0x6cb: 0x0008,
+	0x6cc: 0x0008, 0x6cd: 0x0040, 0x6ce: 0x0040, 0x6cf: 0x0008, 0x6d0: 0x0008, 0x6d1: 0x0040,
+	0x6d2: 0x0040, 0x6d3: 0x0008, 0x6d4: 0x0008, 0x6d5: 0x0008, 0x6d6: 0x0008, 0x6d7: 0x0008,
+	0x6d8: 0x0008, 0x6d9: 0x0008, 0x6da: 0x0008, 0x6db: 0x0008, 0x6dc: 0x0008, 0x6dd: 0x0008,
+	0x6de: 0x0008, 0x6df: 0x0008, 0x6e0: 0x0008, 0x6e1: 0x0008, 0x6e2: 0x0008, 0x6e3: 0x0008,
+	0x6e4: 0x0008, 0x6e5: 0x0008, 0x6e6: 0x0008, 0x6e7: 0x0008, 0x6e8: 0x0008, 0x6e9: 0x0040,
+	0x6ea: 0x0008, 0x6eb: 0x0008, 0x6ec: 0x0008, 0x6ed: 0x0008, 0x6ee: 0x0008, 0x6ef: 0x0008,
+	0x6f0: 0x0008, 0x6f1: 0x0040, 0x6f2: 0x0008, 0x6f3: 0x0008, 0x6f4: 0x0040, 0x6f5: 0x0008,
+	0x6f6: 0x0008, 0x6f7: 0x0008, 0x6f8: 0x0008, 0x6f9: 0x0008, 0x6fa: 0x0040, 0x6fb: 0x0040,
+	0x6fc: 0x1308, 0x6fd: 0x0008, 0x6fe: 0x1008, 0x6ff: 0x1308,
+	// Block 0x1c, offset 0x700
+	0x700: 0x1008, 0x701: 0x1308, 0x702: 0x1308, 0x703: 0x1308, 0x704: 0x1308, 0x705: 0x0040,
+	0x706: 0x0040, 0x707: 0x1008, 0x708: 0x1008, 0x709: 0x0040, 0x70a: 0x0040, 0x70b: 0x1008,
+	0x70c: 0x1008, 0x70d: 0x1b08, 0x70e: 0x0040, 0x70f: 0x0040, 0x710: 0x0040, 0x711: 0x0040,
+	0x712: 0x0040, 0x713: 0x0040, 0x714: 0x0040, 0x715: 0x0040, 0x716: 0x1308, 0x717: 0x1008,
+	0x718: 0x0040, 0x719: 0x0040, 0x71a: 0x0040, 0x71b: 0x0040, 0x71c: 0x0881, 0x71d: 0x08b9,
+	0x71e: 0x0040, 0x71f: 0x0008, 0x720: 0x0008, 0x721: 0x0008, 0x722: 0x1308, 0x723: 0x1308,
+	0x724: 0x0040, 0x725: 0x0040, 0x726: 0x0008, 0x727: 0x0008, 0x728: 0x0008, 0x729: 0x0008,
+	0x72a: 0x0008, 0x72b: 0x0008, 0x72c: 0x0008, 0x72d: 0x0008, 0x72e: 0x0008, 0x72f: 0x0008,
+	0x730: 0x0018, 0x731: 0x0008, 0x732: 0x0018, 0x733: 0x0018, 0x734: 0x0018, 0x735: 0x0018,
+	0x736: 0x0018, 0x737: 0x0018, 0x738: 0x0040, 0x739: 0x0040, 0x73a: 0x0040, 0x73b: 0x0040,
+	0x73c: 0x0040, 0x73d: 0x0040, 0x73e: 0x0040, 0x73f: 0x0040,
+	// Block 0x1d, offset 0x740
+	0x740: 0x0040, 0x741: 0x0040, 0x742: 0x1308, 0x743: 0x0008, 0x744: 0x0040, 0x745: 0x0008,
+	0x746: 0x0008, 0x747: 0x0008, 0x748: 0x0008, 0x749: 0x0008, 0x74a: 0x0008, 0x74b: 0x0040,
+	0x74c: 0x0040, 0x74d: 0x0040, 0x74e: 0x0008, 0x74f: 0x0008, 0x750: 0x0008, 0x751: 0x0040,
+	0x752: 0x0008, 0x753: 0x0008, 0x754: 0x0008, 0x755: 0x0008, 0x756: 0x0040, 0x757: 0x0040,
+	0x758: 0x0040, 0x759: 0x0008, 0x75a: 0x0008, 0x75b: 0x0040, 0x75c: 0x0008, 0x75d: 0x0040,
+	0x75e: 0x0008, 0x75f: 0x0008, 0x760: 0x0040, 0x761: 0x0040, 0x762: 0x0040, 0x763: 0x0008,
+	0x764: 0x0008, 0x765: 0x0040, 0x766: 0x0040, 0x767: 0x0040, 0x768: 0x0008, 0x769: 0x0008,
+	0x76a: 0x0008, 0x76b: 0x0040, 0x76c: 0x0040, 0x76d: 0x0040, 0x76e: 0x0008, 0x76f: 0x0008,
+	0x770: 0x0008, 0x771: 0x0008, 0x772: 0x0008, 0x773: 0x0008, 0x774: 0x0008, 0x775: 0x0008,
+	0x776: 0x0008, 0x777: 0x0008, 0x778: 0x0008, 0x779: 0x0008, 0x77a: 0x0040, 0x77b: 0x0040,
+	0x77c: 0x0040, 0x77d: 0x0040, 0x77e: 0x1008, 0x77f: 0x1008,
+	// Block 0x1e, offset 0x780
+	0x780: 0x1308, 0x781: 0x1008, 0x782: 0x1008, 0x783: 0x1008, 0x784: 0x1008, 0x785: 0x0040,
+	0x786: 0x1308, 0x787: 0x1308, 0x788: 0x1308, 0x789: 0x0040, 0x78a: 0x1308, 0x78b: 0x1308,
+	0x78c: 0x1308, 0x78d: 0x1b08, 0x78e: 0x0040, 0x78f: 0x0040, 0x790: 0x0040, 0x791: 0x0040,
+	0x792: 0x0040, 0x793: 0x0040, 0x794: 0x0040, 0x795: 0x1308, 0x796: 0x1308, 0x797: 0x0040,
+	0x798: 0x0008, 0x799: 0x0008, 0x79a: 0x0008, 0x79b: 0x0040, 0x79c: 0x0040, 0x79d: 0x0040,
+	0x79e: 0x0040, 0x79f: 0x0040, 0x7a0: 0x0008, 0x7a1: 0x0008, 0x7a2: 0x1308, 0x7a3: 0x1308,
+	0x7a4: 0x0040, 0x7a5: 0x0040, 0x7a6: 0x0008, 0x7a7: 0x0008, 0x7a8: 0x0008, 0x7a9: 0x0008,
+	0x7aa: 0x0008, 0x7ab: 0x0008, 0x7ac: 0x0008, 0x7ad: 0x0008, 0x7ae: 0x0008, 0x7af: 0x0008,
+	0x7b0: 0x0040, 0x7b1: 0x0040, 0x7b2: 0x0040, 0x7b3: 0x0040, 0x7b4: 0x0040, 0x7b5: 0x0040,
+	0x7b6: 0x0040, 0x7b7: 0x0040, 0x7b8: 0x0018, 0x7b9: 0x0018, 0x7ba: 0x0018, 0x7bb: 0x0018,
+	0x7bc: 0x0018, 0x7bd: 0x0018, 0x7be: 0x0018, 0x7bf: 0x0018,
+	// Block 0x1f, offset 0x7c0
+	0x7c0: 0x0008, 0x7c1: 0x1308, 0x7c2: 0x1008, 0x7c3: 0x1008, 0x7c4: 0x0040, 0x7c5: 0x0008,
+	0x7c6: 0x0008, 0x7c7: 0x0008, 0x7c8: 0x0008, 0x7c9: 0x0008, 0x7ca: 0x0008, 0x7cb: 0x0008,
+	0x7cc: 0x0008, 0x7cd: 0x0040, 0x7ce: 0x0008, 0x7cf: 0x0008, 0x7d0: 0x0008, 0x7d1: 0x0040,
+	0x7d2: 0x0008, 0x7d3: 0x0008, 0x7d4: 0x0008, 0x7d5: 0x0008, 0x7d6: 0x0008, 0x7d7: 0x0008,
+	0x7d8: 0x0008, 0x7d9: 0x0008, 0x7da: 0x0008, 0x7db: 0x0008, 0x7dc: 0x0008, 0x7dd: 0x0008,
+	0x7de: 0x0008, 0x7df: 0x0008, 0x7e0: 0x0008, 0x7e1: 0x0008, 0x7e2: 0x0008, 0x7e3: 0x0008,
+	0x7e4: 0x0008, 0x7e5: 0x0008, 0x7e6: 0x0008, 0x7e7: 0x0008, 0x7e8: 0x0008, 0x7e9: 0x0040,
+	0x7ea: 0x0008, 0x7eb: 0x0008, 0x7ec: 0x0008, 0x7ed: 0x0008, 0x7ee: 0x0008, 0x7ef: 0x0008,
+	0x7f0: 0x0008, 0x7f1: 0x0008, 0x7f2: 0x0008, 0x7f3: 0x0008, 0x7f4: 0x0040, 0x7f5: 0x0008,
+	0x7f6: 0x0008, 0x7f7: 0x0008, 0x7f8: 0x0008, 0x7f9: 0x0008, 0x7fa: 0x0040, 0x7fb: 0x0040,
+	0x7fc: 0x1308, 0x7fd: 0x0008, 0x7fe: 0x1008, 0x7ff: 0x1308,
+	// Block 0x20, offset 0x800
+	0x800: 0x1008, 0x801: 0x1008, 0x802: 0x1008, 0x803: 0x1008, 0x804: 0x1008, 0x805: 0x0040,
+	0x806: 0x1308, 0x807: 0x1008, 0x808: 0x1008, 0x809: 0x0040, 0x80a: 0x1008, 0x80b: 0x1008,
+	0x80c: 0x1308, 0x80d: 0x1b08, 0x80e: 0x0040, 0x80f: 0x0040, 0x810: 0x0040, 0x811: 0x0040,
+	0x812: 0x0040, 0x813: 0x0040, 0x814: 0x0040, 0x815: 0x1008, 0x816: 0x1008, 0x817: 0x0040,
+	0x818: 0x0040, 0x819: 0x0040, 0x81a: 0x0040, 0x81b: 0x0040, 0x81c: 0x0040, 0x81d: 0x0040,
+	0x81e: 0x0008, 0x81f: 0x0040, 0x820: 0x0008, 0x821: 0x0008, 0x822: 0x1308, 0x823: 0x1308,
+	0x824: 0x0040, 0x825: 0x0040, 0x826: 0x0008, 0x827: 0x0008, 0x828: 0x0008, 0x829: 0x0008,
+	0x82a: 0x0008, 0x82b: 0x0008, 0x82c: 0x0008, 0x82d: 0x0008, 0x82e: 0x0008, 0x82f: 0x0008,
+	0x830: 0x0040, 0x831: 0x0008, 0x832: 0x0008, 0x833: 0x0040, 0x834: 0x0040, 0x835: 0x0040,
+	0x836: 0x0040, 0x837: 0x0040, 0x838: 0x0040, 0x839: 0x0040, 0x83a: 0x0040, 0x83b: 0x0040,
+	0x83c: 0x0040, 0x83d: 0x0040, 0x83e: 0x0040, 0x83f: 0x0040,
+	// Block 0x21, offset 0x840
+	0x840: 0x1008, 0x841: 0x1308, 0x842: 0x1308, 0x843: 0x1308, 0x844: 0x1308, 0x845: 0x0040,
+	0x846: 0x1008, 0x847: 0x1008, 0x848: 0x1008, 0x849: 0x0040, 0x84a: 0x1008, 0x84b: 0x1008,
+	0x84c: 0x1008, 0x84d: 0x1b08, 0x84e: 0x0008, 0x84f: 0x0018, 0x850: 0x0040, 0x851: 0x0040,
+	0x852: 0x0040, 0x853: 0x0040, 0x854: 0x0008, 0x855: 0x0008, 0x856: 0x0008, 0x857: 0x1008,
+	0x858: 0x0018, 0x859: 0x0018, 0x85a: 0x0018, 0x85b: 0x0018, 0x85c: 0x0018, 0x85d: 0x0018,
+	0x85e: 0x0018, 0x85f: 0x0008, 0x860: 0x0008, 0x861: 0x0008, 0x862: 0x1308, 0x863: 0x1308,
+	0x864: 0x0040, 0x865: 0x0040, 0x866: 0x0008, 0x867: 0x0008, 0x868: 0x0008, 0x869: 0x0008,
+	0x86a: 0x0008, 0x86b: 0x0008, 0x86c: 0x0008, 0x86d: 0x0008, 0x86e: 0x0008, 0x86f: 0x0008,
+	0x870: 0x0018, 0x871: 0x0018, 0x872: 0x0018, 0x873: 0x0018, 0x874: 0x0018, 0x875: 0x0018,
+	0x876: 0x0018, 0x877: 0x0018, 0x878: 0x0018, 0x879: 0x0018, 0x87a: 0x0008, 0x87b: 0x0008,
+	0x87c: 0x0008, 0x87d: 0x0008, 0x87e: 0x0008, 0x87f: 0x0008,
+	// Block 0x22, offset 0x880
+	0x880: 0x0040, 0x881: 0x0008, 0x882: 0x0008, 0x883: 0x0040, 0x884: 0x0008, 0x885: 0x0040,
+	0x886: 0x0040, 0x887: 0x0008, 0x888: 0x0008, 0x889: 0x0040, 0x88a: 0x0008, 0x88b: 0x0040,
+	0x88c: 0x0040, 0x88d: 0x0008, 0x88e: 0x0040, 0x88f: 0x0040, 0x890: 0x0040, 0x891: 0x0040,
+	0x892: 0x0040, 0x893: 0x0040, 0x894: 0x0008, 0x895: 0x0008, 0x896: 0x0008, 0x897: 0x0008,
+	0x898: 0x0040, 0x899: 0x0008, 0x89a: 0x0008, 0x89b: 0x0008, 0x89c: 0x0008, 0x89d: 0x0008,
+	0x89e: 0x0008, 0x89f: 0x0008, 0x8a0: 0x0040, 0x8a1: 0x0008, 0x8a2: 0x0008, 0x8a3: 0x0008,
+	0x8a4: 0x0040, 0x8a5: 0x0008, 0x8a6: 0x0040, 0x8a7: 0x0008, 0x8a8: 0x0040, 0x8a9: 0x0040,
+	0x8aa: 0x0008, 0x8ab: 0x0008, 0x8ac: 0x0040, 0x8ad: 0x0008, 0x8ae: 0x0008, 0x8af: 0x0008,
+	0x8b0: 0x0008, 0x8b1: 0x1308, 0x8b2: 0x0008, 0x8b3: 0x0929, 0x8b4: 0x1308, 0x8b5: 0x1308,
+	0x8b6: 0x1308, 0x8b7: 0x1308, 0x8b8: 0x1308, 0x8b9: 0x1308, 0x8ba: 0x0040, 0x8bb: 0x1308,
+	0x8bc: 0x1308, 0x8bd: 0x0008, 0x8be: 0x0040, 0x8bf: 0x0040,
+	// Block 0x23, offset 0x8c0
+	0x8c0: 0x0008, 0x8c1: 0x0008, 0x8c2: 0x0008, 0x8c3: 0x09d1, 0x8c4: 0x0008, 0x8c5: 0x0008,
+	0x8c6: 0x0008, 0x8c7: 0x0008, 0x8c8: 0x0040, 0x8c9: 0x0008, 0x8ca: 0x0008, 0x8cb: 0x0008,
+	0x8cc: 0x0008, 0x8cd: 0x0a09, 0x8ce: 0x0008, 0x8cf: 0x0008, 0x8d0: 0x0008, 0x8d1: 0x0008,
+	0x8d2: 0x0a41, 0x8d3: 0x0008, 0x8d4: 0x0008, 0x8d5: 0x0008, 0x8d6: 0x0008, 0x8d7: 0x0a79,
+	0x8d8: 0x0008, 0x8d9: 0x0008, 0x8da: 0x0008, 0x8db: 0x0008, 0x8dc: 0x0ab1, 0x8dd: 0x0008,
+	0x8de: 0x0008, 0x8df: 0x0008, 0x8e0: 0x0008, 0x8e1: 0x0008, 0x8e2: 0x0008, 0x8e3: 0x0008,
+	0x8e4: 0x0008, 0x8e5: 0x0008, 0x8e6: 0x0008, 0x8e7: 0x0008, 0x8e8: 0x0008, 0x8e9: 0x0ae9,
+	0x8ea: 0x0008, 0x8eb: 0x0008, 0x8ec: 0x0008, 0x8ed: 0x0040, 0x8ee: 0x0040, 0x8ef: 0x0040,
+	0x8f0: 0x0040, 0x8f1: 0x1308, 0x8f2: 0x1308, 0x8f3: 0x0b21, 0x8f4: 0x1308, 0x8f5: 0x0b59,
+	0x8f6: 0x0b91, 0x8f7: 0x0bc9, 0x8f8: 0x0c19, 0x8f9: 0x0c51, 0x8fa: 0x1308, 0x8fb: 0x1308,
+	0x8fc: 0x1308, 0x8fd: 0x1308, 0x8fe: 0x1308, 0x8ff: 0x1008,
+	// Block 0x24, offset 0x900
+	0x900: 0x1308, 0x901: 0x0ca1, 0x902: 0x1308, 0x903: 0x1308, 0x904: 0x1b08, 0x905: 0x0018,
+	0x906: 0x1308, 0x907: 0x1308, 0x908: 0x0008, 0x909: 0x0008, 0x90a: 0x0008, 0x90b: 0x0008,
+	0x90c: 0x0008, 0x90d: 0x1308, 0x90e: 0x1308, 0x90f: 0x1308, 0x910: 0x1308, 0x911: 0x1308,
+	0x912: 0x1308, 0x913: 0x0cd9, 0x914: 0x1308, 0x915: 0x1308, 0x916: 0x1308, 0x917: 0x1308,
+	0x918: 0x0040, 0x919: 0x1308, 0x91a: 0x1308, 0x91b: 0x1308, 0x91c: 0x1308, 0x91d: 0x0d11,
+	0x91e: 0x1308, 0x91f: 0x1308, 0x920: 0x1308, 0x921: 0x1308, 0x922: 0x0d49, 0x923: 0x1308,
+	0x924: 0x1308, 0x925: 0x1308, 0x926: 0x1308, 0x927: 0x0d81, 0x928: 0x1308, 0x929: 0x1308,
+	0x92a: 0x1308, 0x92b: 0x1308, 0x92c: 0x0db9, 0x92d: 0x1308, 0x92e: 0x1308, 0x92f: 0x1308,
+	0x930: 0x1308, 0x931: 0x1308, 0x932: 0x1308, 0x933: 0x1308, 0x934: 0x1308, 0x935: 0x1308,
+	0x936: 0x1308, 0x937: 0x1308, 0x938: 0x1308, 0x939: 0x0df1, 0x93a: 0x1308, 0x93b: 0x1308,
+	0x93c: 0x1308, 0x93d: 0x0040, 0x93e: 0x0018, 0x93f: 0x0018,
+	// Block 0x25, offset 0x940
+	0x940: 0x0008, 0x941: 0x0008, 0x942: 0x0008, 0x943: 0x0008, 0x944: 0x0008, 0x945: 0x0008,
+	0x946: 0x0008, 0x947: 0x0008, 0x948: 0x0008, 0x949: 0x0008, 0x94a: 0x0008, 0x94b: 0x0008,
+	0x94c: 0x0008, 0x94d: 0x0008, 0x94e: 0x0008, 0x94f: 0x0008, 0x950: 0x0008, 0x951: 0x0008,
+	0x952: 0x0008, 0x953: 0x0008, 0x954: 0x0008, 0x955: 0x0008, 0x956: 0x0008, 0x957: 0x0008,
+	0x958: 0x0008, 0x959: 0x0008, 0x95a: 0x0008, 0x95b: 0x0008, 0x95c: 0x0008, 0x95d: 0x0008,
+	0x95e: 0x0008, 0x95f: 0x0008, 0x960: 0x0008, 0x961: 0x0008, 0x962: 0x0008, 0x963: 0x0008,
+	0x964: 0x0008, 0x965: 0x0008, 0x966: 0x0008, 0x967: 0x0008, 0x968: 0x0008, 0x969: 0x0008,
+	0x96a: 0x0008, 0x96b: 0x0008, 0x96c: 0x0039, 0x96d: 0x0ed1, 0x96e: 0x0ee9, 0x96f: 0x0008,
+	0x970: 0x0ef9, 0x971: 0x0f09, 0x972: 0x0f19, 0x973: 0x0f31, 0x974: 0x0249, 0x975: 0x0f41,
+	0x976: 0x0259, 0x977: 0x0f51, 0x978: 0x0359, 0x979: 0x0f61, 0x97a: 0x0f71, 0x97b: 0x0008,
+	0x97c: 0x00d9, 0x97d: 0x0f81, 0x97e: 0x0f99, 0x97f: 0x0269,
+	// Block 0x26, offset 0x980
+	0x980: 0x0fa9, 0x981: 0x0fb9, 0x982: 0x0279, 0x983: 0x0039, 0x984: 0x0fc9, 0x985: 0x0fe1,
+	0x986: 0x059d, 0x987: 0x0ee9, 0x988: 0x0ef9, 0x989: 0x0f09, 0x98a: 0x0ff9, 0x98b: 0x1011,
+	0x98c: 0x1029, 0x98d: 0x0f31, 0x98e: 0x0008, 0x98f: 0x0f51, 0x990: 0x0f61, 0x991: 0x1041,
+	0x992: 0x00d9, 0x993: 0x1059, 0x994: 0x05b5, 0x995: 0x05b5, 0x996: 0x0f99, 0x997: 0x0fa9,
+	0x998: 0x0fb9, 0x999: 0x059d, 0x99a: 0x1071, 0x99b: 0x1089, 0x99c: 0x05cd, 0x99d: 0x1099,
+	0x99e: 0x10b1, 0x99f: 0x10c9, 0x9a0: 0x10e1, 0x9a1: 0x10f9, 0x9a2: 0x0f41, 0x9a3: 0x0269,
+	0x9a4: 0x0fb9, 0x9a5: 0x1089, 0x9a6: 0x1099, 0x9a7: 0x10b1, 0x9a8: 0x1111, 0x9a9: 0x10e1,
+	0x9aa: 0x10f9, 0x9ab: 0x0008, 0x9ac: 0x0008, 0x9ad: 0x0008, 0x9ae: 0x0008, 0x9af: 0x0008,
+	0x9b0: 0x0008, 0x9b1: 0x0008, 0x9b2: 0x0008, 0x9b3: 0x0008, 0x9b4: 0x0008, 0x9b5: 0x0008,
+	0x9b6: 0x0008, 0x9b7: 0x0008, 0x9b8: 0x1129, 0x9b9: 0x0008, 0x9ba: 0x0008, 0x9bb: 0x0008,
+	0x9bc: 0x0008, 0x9bd: 0x0008, 0x9be: 0x0008, 0x9bf: 0x0008,
+	// Block 0x27, offset 0x9c0
+	0x9c0: 0x0008, 0x9c1: 0x0008, 0x9c2: 0x0008, 0x9c3: 0x0008, 0x9c4: 0x0008, 0x9c5: 0x0008,
+	0x9c6: 0x0008, 0x9c7: 0x0008, 0x9c8: 0x0008, 0x9c9: 0x0008, 0x9ca: 0x0008, 0x9cb: 0x0008,
+	0x9cc: 0x0008, 0x9cd: 0x0008, 0x9ce: 0x0008, 0x9cf: 0x0008, 0x9d0: 0x0008, 0x9d1: 0x0008,
+	0x9d2: 0x0008, 0x9d3: 0x0008, 0x9d4: 0x0008, 0x9d5: 0x0008, 0x9d6: 0x0008, 0x9d7: 0x0008,
+	0x9d8: 0x0008, 0x9d9: 0x0008, 0x9da: 0x0008, 0x9db: 0x1141, 0x9dc: 0x1159, 0x9dd: 0x1169,
+	0x9de: 0x1181, 0x9df: 0x1029, 0x9e0: 0x1199, 0x9e1: 0x11a9, 0x9e2: 0x11c1, 0x9e3: 0x11d9,
+	0x9e4: 0x11f1, 0x9e5: 0x1209, 0x9e6: 0x1221, 0x9e7: 0x05e5, 0x9e8: 0x1239, 0x9e9: 0x1251,
+	0x9ea: 0xe17d, 0x9eb: 0x1269, 0x9ec: 0x1281, 0x9ed: 0x1299, 0x9ee: 0x12b1, 0x9ef: 0x12c9,
+	0x9f0: 0x12e1, 0x9f1: 0x12f9, 0x9f2: 0x1311, 0x9f3: 0x1329, 0x9f4: 0x1341, 0x9f5: 0x1359,
+	0x9f6: 0x1371, 0x9f7: 0x1389, 0x9f8: 0x05fd, 0x9f9: 0x13a1, 0x9fa: 0x13b9, 0x9fb: 0x13d1,
+	0x9fc: 0x13e1, 0x9fd: 0x13f9, 0x9fe: 0x1411, 0x9ff: 0x1429,
+	// Block 0x28, offset 0xa00
+	0xa00: 0xe00d, 0xa01: 0x0008, 0xa02: 0xe00d, 0xa03: 0x0008, 0xa04: 0xe00d, 0xa05: 0x0008,
+	0xa06: 0xe00d, 0xa07: 0x0008, 0xa08: 0xe00d, 0xa09: 0x0008, 0xa0a: 0xe00d, 0xa0b: 0x0008,
+	0xa0c: 0xe00d, 0xa0d: 0x0008, 0xa0e: 0xe00d, 0xa0f: 0x0008, 0xa10: 0xe00d, 0xa11: 0x0008,
+	0xa12: 0xe00d, 0xa13: 0x0008, 0xa14: 0xe00d, 0xa15: 0x0008, 0xa16: 0xe00d, 0xa17: 0x0008,
+	0xa18: 0xe00d, 0xa19: 0x0008, 0xa1a: 0xe00d, 0xa1b: 0x0008, 0xa1c: 0xe00d, 0xa1d: 0x0008,
+	0xa1e: 0xe00d, 0xa1f: 0x0008, 0xa20: 0xe00d, 0xa21: 0x0008, 0xa22: 0xe00d, 0xa23: 0x0008,
+	0xa24: 0xe00d, 0xa25: 0x0008, 0xa26: 0xe00d, 0xa27: 0x0008, 0xa28: 0xe00d, 0xa29: 0x0008,
+	0xa2a: 0xe00d, 0xa2b: 0x0008, 0xa2c: 0xe00d, 0xa2d: 0x0008, 0xa2e: 0xe00d, 0xa2f: 0x0008,
+	0xa30: 0xe00d, 0xa31: 0x0008, 0xa32: 0xe00d, 0xa33: 0x0008, 0xa34: 0xe00d, 0xa35: 0x0008,
+	0xa36: 0xe00d, 0xa37: 0x0008, 0xa38: 0xe00d, 0xa39: 0x0008, 0xa3a: 0xe00d, 0xa3b: 0x0008,
+	0xa3c: 0xe00d, 0xa3d: 0x0008, 0xa3e: 0xe00d, 0xa3f: 0x0008,
+	// Block 0x29, offset 0xa40
+	0xa40: 0xe00d, 0xa41: 0x0008, 0xa42: 0xe00d, 0xa43: 0x0008, 0xa44: 0xe00d, 0xa45: 0x0008,
+	0xa46: 0xe00d, 0xa47: 0x0008, 0xa48: 0xe00d, 0xa49: 0x0008, 0xa4a: 0xe00d, 0xa4b: 0x0008,
+	0xa4c: 0xe00d, 0xa4d: 0x0008, 0xa4e: 0xe00d, 0xa4f: 0x0008, 0xa50: 0xe00d, 0xa51: 0x0008,
+	0xa52: 0xe00d, 0xa53: 0x0008, 0xa54: 0xe00d, 0xa55: 0x0008, 0xa56: 0x0008, 0xa57: 0x0008,
+	0xa58: 0x0008, 0xa59: 0x0008, 0xa5a: 0x0615, 0xa5b: 0x0635, 0xa5c: 0x0008, 0xa5d: 0x0008,
+	0xa5e: 0x1441, 0xa5f: 0x0008, 0xa60: 0xe00d, 0xa61: 0x0008, 0xa62: 0xe00d, 0xa63: 0x0008,
+	0xa64: 0xe00d, 0xa65: 0x0008, 0xa66: 0xe00d, 0xa67: 0x0008, 0xa68: 0xe00d, 0xa69: 0x0008,
+	0xa6a: 0xe00d, 0xa6b: 0x0008, 0xa6c: 0xe00d, 0xa6d: 0x0008, 0xa6e: 0xe00d, 0xa6f: 0x0008,
+	0xa70: 0xe00d, 0xa71: 0x0008, 0xa72: 0xe00d, 0xa73: 0x0008, 0xa74: 0xe00d, 0xa75: 0x0008,
+	0xa76: 0xe00d, 0xa77: 0x0008, 0xa78: 0xe00d, 0xa79: 0x0008, 0xa7a: 0xe00d, 0xa7b: 0x0008,
+	0xa7c: 0xe00d, 0xa7d: 0x0008, 0xa7e: 0xe00d, 0xa7f: 0x0008,
+	// Block 0x2a, offset 0xa80
+	0xa80: 0x0008, 0xa81: 0x0008, 0xa82: 0x0008, 0xa83: 0x0008, 0xa84: 0x0008, 0xa85: 0x0008,
+	0xa86: 0x0040, 0xa87: 0x0040, 0xa88: 0xe045, 0xa89: 0xe045, 0xa8a: 0xe045, 0xa8b: 0xe045,
+	0xa8c: 0xe045, 0xa8d: 0xe045, 0xa8e: 0x0040, 0xa8f: 0x0040, 0xa90: 0x0008, 0xa91: 0x0008,
+	0xa92: 0x0008, 0xa93: 0x0008, 0xa94: 0x0008, 0xa95: 0x0008, 0xa96: 0x0008, 0xa97: 0x0008,
+	0xa98: 0x0040, 0xa99: 0xe045, 0xa9a: 0x0040, 0xa9b: 0xe045, 0xa9c: 0x0040, 0xa9d: 0xe045,
+	0xa9e: 0x0040, 0xa9f: 0xe045, 0xaa0: 0x0008, 0xaa1: 0x0008, 0xaa2: 0x0008, 0xaa3: 0x0008,
+	0xaa4: 0x0008, 0xaa5: 0x0008, 0xaa6: 0x0008, 0xaa7: 0x0008, 0xaa8: 0xe045, 0xaa9: 0xe045,
+	0xaaa: 0xe045, 0xaab: 0xe045, 0xaac: 0xe045, 0xaad: 0xe045, 0xaae: 0xe045, 0xaaf: 0xe045,
+	0xab0: 0x0008, 0xab1: 0x1459, 0xab2: 0x0008, 0xab3: 0x1471, 0xab4: 0x0008, 0xab5: 0x1489,
+	0xab6: 0x0008, 0xab7: 0x14a1, 0xab8: 0x0008, 0xab9: 0x14b9, 0xaba: 0x0008, 0xabb: 0x14d1,
+	0xabc: 0x0008, 0xabd: 0x14e9, 0xabe: 0x0040, 0xabf: 0x0040,
+	// Block 0x2b, offset 0xac0
+	0xac0: 0x1501, 0xac1: 0x1531, 0xac2: 0x1561, 0xac3: 0x1591, 0xac4: 0x15c1, 0xac5: 0x15f1,
+	0xac6: 0x1621, 0xac7: 0x1651, 0xac8: 0x1501, 0xac9: 0x1531, 0xaca: 0x1561, 0xacb: 0x1591,
+	0xacc: 0x15c1, 0xacd: 0x15f1, 0xace: 0x1621, 0xacf: 0x1651, 0xad0: 0x1681, 0xad1: 0x16b1,
+	0xad2: 0x16e1, 0xad3: 0x1711, 0xad4: 0x1741, 0xad5: 0x1771, 0xad6: 0x17a1, 0xad7: 0x17d1,
+	0xad8: 0x1681, 0xad9: 0x16b1, 0xada: 0x16e1, 0xadb: 0x1711, 0xadc: 0x1741, 0xadd: 0x1771,
+	0xade: 0x17a1, 0xadf: 0x17d1, 0xae0: 0x1801, 0xae1: 0x1831, 0xae2: 0x1861, 0xae3: 0x1891,
+	0xae4: 0x18c1, 0xae5: 0x18f1, 0xae6: 0x1921, 0xae7: 0x1951, 0xae8: 0x1801, 0xae9: 0x1831,
+	0xaea: 0x1861, 0xaeb: 0x1891, 0xaec: 0x18c1, 0xaed: 0x18f1, 0xaee: 0x1921, 0xaef: 0x1951,
+	0xaf0: 0x0008, 0xaf1: 0x0008, 0xaf2: 0x1981, 0xaf3: 0x19b1, 0xaf4: 0x19d9, 0xaf5: 0x0040,
+	0xaf6: 0x0008, 0xaf7: 0x1a01, 0xaf8: 0xe045, 0xaf9: 0xe045, 0xafa: 0x064d, 0xafb: 0x1459,
+	0xafc: 0x19b1, 0xafd: 0x0666, 0xafe: 0x1a31, 0xaff: 0x0686,
+	// Block 0x2c, offset 0xb00
+	0xb00: 0x06a6, 0xb01: 0x1a4a, 0xb02: 0x1a79, 0xb03: 0x1aa9, 0xb04: 0x1ad1, 0xb05: 0x0040,
+	0xb06: 0x0008, 0xb07: 0x1af9, 0xb08: 0x06c5, 0xb09: 0x1471, 0xb0a: 0x06dd, 0xb0b: 0x1489,
+	0xb0c: 0x1aa9, 0xb0d: 0x1b2a, 0xb0e: 0x1b5a, 0xb0f: 0x1b8a, 0xb10: 0x0008, 0xb11: 0x0008,
+	0xb12: 0x0008, 0xb13: 0x1bb9, 0xb14: 0x0040, 0xb15: 0x0040, 0xb16: 0x0008, 0xb17: 0x0008,
+	0xb18: 0xe045, 0xb19: 0xe045, 0xb1a: 0x06f5, 0xb1b: 0x14a1, 0xb1c: 0x0040, 0xb1d: 0x1bd2,
+	0xb1e: 0x1c02, 0xb1f: 0x1c32, 0xb20: 0x0008, 0xb21: 0x0008, 0xb22: 0x0008, 0xb23: 0x1c61,
+	0xb24: 0x0008, 0xb25: 0x0008, 0xb26: 0x0008, 0xb27: 0x0008, 0xb28: 0xe045, 0xb29: 0xe045,
+	0xb2a: 0x070d, 0xb2b: 0x14d1, 0xb2c: 0xe04d, 0xb2d: 0x1c7a, 0xb2e: 0x03d2, 0xb2f: 0x1caa,
+	0xb30: 0x0040, 0xb31: 0x0040, 0xb32: 0x1cb9, 0xb33: 0x1ce9, 0xb34: 0x1d11, 0xb35: 0x0040,
+	0xb36: 0x0008, 0xb37: 0x1d39, 0xb38: 0x0725, 0xb39: 0x14b9, 0xb3a: 0x0515, 0xb3b: 0x14e9,
+	0xb3c: 0x1ce9, 0xb3d: 0x073e, 0xb3e: 0x075e, 0xb3f: 0x0040,
+	// Block 0x2d, offset 0xb40
+	0xb40: 0x000a, 0xb41: 0x000a, 0xb42: 0x000a, 0xb43: 0x000a, 0xb44: 0x000a, 0xb45: 0x000a,
+	0xb46: 0x000a, 0xb47: 0x000a, 0xb48: 0x000a, 0xb49: 0x000a, 0xb4a: 0x000a, 0xb4b: 0x03c0,
+	0xb4c: 0x0003, 0xb4d: 0x0003, 0xb4e: 0x0340, 0xb4f: 0x0340, 0xb50: 0x0018, 0xb51: 0xe00d,
+	0xb52: 0x0018, 0xb53: 0x0018, 0xb54: 0x0018, 0xb55: 0x0018, 0xb56: 0x0018, 0xb57: 0x077e,
+	0xb58: 0x0018, 0xb59: 0x0018, 0xb5a: 0x0018, 0xb5b: 0x0018, 0xb5c: 0x0018, 0xb5d: 0x0018,
+	0xb5e: 0x0018, 0xb5f: 0x0018, 0xb60: 0x0018, 0xb61: 0x0018, 0xb62: 0x0018, 0xb63: 0x0018,
+	0xb64: 0x0040, 0xb65: 0x0040, 0xb66: 0x0040, 0xb67: 0x0018, 0xb68: 0x0040, 0xb69: 0x0040,
+	0xb6a: 0x0340, 0xb6b: 0x0340, 0xb6c: 0x0340, 0xb6d: 0x0340, 0xb6e: 0x0340, 0xb6f: 0x000a,
+	0xb70: 0x0018, 0xb71: 0x0018, 0xb72: 0x0018, 0xb73: 0x1d69, 0xb74: 0x1da1, 0xb75: 0x0018,
+	0xb76: 0x1df1, 0xb77: 0x1e29, 0xb78: 0x0018, 0xb79: 0x0018, 0xb7a: 0x0018, 0xb7b: 0x0018,
+	0xb7c: 0x1e7a, 0xb7d: 0x0018, 0xb7e: 0x079e, 0xb7f: 0x0018,
+	// Block 0x2e, offset 0xb80
+	0xb80: 0x0018, 0xb81: 0x0018, 0xb82: 0x0018, 0xb83: 0x0018, 0xb84: 0x0018, 0xb85: 0x0018,
+	0xb86: 0x0018, 0xb87: 0x1e92, 0xb88: 0x1eaa, 0xb89: 0x1ec2, 0xb8a: 0x0018, 0xb8b: 0x0018,
+	0xb8c: 0x0018, 0xb8d: 0x0018, 0xb8e: 0x0018, 0xb8f: 0x0018, 0xb90: 0x0018, 0xb91: 0x0018,
+	0xb92: 0x0018, 0xb93: 0x0018, 0xb94: 0x0018, 0xb95: 0x0018, 0xb96: 0x0018, 0xb97: 0x1ed9,
+	0xb98: 0x0018, 0xb99: 0x0018, 0xb9a: 0x0018, 0xb9b: 0x0018, 0xb9c: 0x0018, 0xb9d: 0x0018,
+	0xb9e: 0x0018, 0xb9f: 0x000a, 0xba0: 0x03c0, 0xba1: 0x0340, 0xba2: 0x0340, 0xba3: 0x0340,
+	0xba4: 0x03c0, 0xba5: 0x0040, 0xba6: 0x0040, 0xba7: 0x0040, 0xba8: 0x0040, 0xba9: 0x0040,
+	0xbaa: 0x0340, 0xbab: 0x0340, 0xbac: 0x0340, 0xbad: 0x0340, 0xbae: 0x0340, 0xbaf: 0x0340,
+	0xbb0: 0x1f41, 0xbb1: 0x0f41, 0xbb2: 0x0040, 0xbb3: 0x0040, 0xbb4: 0x1f51, 0xbb5: 0x1f61,
+	0xbb6: 0x1f71, 0xbb7: 0x1f81, 0xbb8: 0x1f91, 0xbb9: 0x1fa1, 0xbba: 0x1fb2, 0xbbb: 0x07bd,
+	0xbbc: 0x1fc2, 0xbbd: 0x1fd2, 0xbbe: 0x1fe2, 0xbbf: 0x0f71,
+	// Block 0x2f, offset 0xbc0
+	0xbc0: 0x1f41, 0xbc1: 0x00c9, 0xbc2: 0x0069, 0xbc3: 0x0079, 0xbc4: 0x1f51, 0xbc5: 0x1f61,
+	0xbc6: 0x1f71, 0xbc7: 0x1f81, 0xbc8: 0x1f91, 0xbc9: 0x1fa1, 0xbca: 0x1fb2, 0xbcb: 0x07d5,
+	0xbcc: 0x1fc2, 0xbcd: 0x1fd2, 0xbce: 0x1fe2, 0xbcf: 0x0040, 0xbd0: 0x0039, 0xbd1: 0x0f09,
+	0xbd2: 0x00d9, 0xbd3: 0x0369, 0xbd4: 0x0ff9, 0xbd5: 0x0249, 0xbd6: 0x0f51, 0xbd7: 0x0359,
+	0xbd8: 0x0f61, 0xbd9: 0x0f71, 0xbda: 0x0f99, 0xbdb: 0x01d9, 0xbdc: 0x0fa9, 0xbdd: 0x0040,
+	0xbde: 0x0040, 0xbdf: 0x0040, 0xbe0: 0x0018, 0xbe1: 0x0018, 0xbe2: 0x0018, 0xbe3: 0x0018,
+	0xbe4: 0x0018, 0xbe5: 0x0018, 0xbe6: 0x0018, 0xbe7: 0x0018, 0xbe8: 0x1ff1, 0xbe9: 0x0018,
+	0xbea: 0x0018, 0xbeb: 0x0018, 0xbec: 0x0018, 0xbed: 0x0018, 0xbee: 0x0018, 0xbef: 0x0018,
+	0xbf0: 0x0018, 0xbf1: 0x0018, 0xbf2: 0x0018, 0xbf3: 0x0018, 0xbf4: 0x0018, 0xbf5: 0x0018,
+	0xbf6: 0x0018, 0xbf7: 0x0018, 0xbf8: 0x0018, 0xbf9: 0x0018, 0xbfa: 0x0018, 0xbfb: 0x0018,
+	0xbfc: 0x0018, 0xbfd: 0x0018, 0xbfe: 0x0018, 0xbff: 0x0040,
+	// Block 0x30, offset 0xc00
+	0xc00: 0x07ee, 0xc01: 0x080e, 0xc02: 0x1159, 0xc03: 0x082d, 0xc04: 0x0018, 0xc05: 0x084e,
+	0xc06: 0x086e, 0xc07: 0x1011, 0xc08: 0x0018, 0xc09: 0x088d, 0xc0a: 0x0f31, 0xc0b: 0x0249,
+	0xc0c: 0x0249, 0xc0d: 0x0249, 0xc0e: 0x0249, 0xc0f: 0x2009, 0xc10: 0x0f41, 0xc11: 0x0f41,
+	0xc12: 0x0359, 0xc13: 0x0359, 0xc14: 0x0018, 0xc15: 0x0f71, 0xc16: 0x2021, 0xc17: 0x0018,
+	0xc18: 0x0018, 0xc19: 0x0f99, 0xc1a: 0x2039, 0xc1b: 0x0269, 0xc1c: 0x0269, 0xc1d: 0x0269,
+	0xc1e: 0x0018, 0xc1f: 0x0018, 0xc20: 0x2049, 0xc21: 0x08ad, 0xc22: 0x2061, 0xc23: 0x0018,
+	0xc24: 0x13d1, 0xc25: 0x0018, 0xc26: 0x2079, 0xc27: 0x0018, 0xc28: 0x13d1, 0xc29: 0x0018,
+	0xc2a: 0x0f51, 0xc2b: 0x2091, 0xc2c: 0x0ee9, 0xc2d: 0x1159, 0xc2e: 0x0018, 0xc2f: 0x0f09,
+	0xc30: 0x0f09, 0xc31: 0x1199, 0xc32: 0x0040, 0xc33: 0x0f61, 0xc34: 0x00d9, 0xc35: 0x20a9,
+	0xc36: 0x20c1, 0xc37: 0x20d9, 0xc38: 0x20f1, 0xc39: 0x0f41, 0xc3a: 0x0018, 0xc3b: 0x08cd,
+	0xc3c: 0x2109, 0xc3d: 0x10b1, 0xc3e: 0x10b1, 0xc3f: 0x2109,
+	// Block 0x31, offset 0xc40
+	0xc40: 0x08ed, 0xc41: 0x0018, 0xc42: 0x0018, 0xc43: 0x0018, 0xc44: 0x0018, 0xc45: 0x0ef9,
+	0xc46: 0x0ef9, 0xc47: 0x0f09, 0xc48: 0x0f41, 0xc49: 0x0259, 0xc4a: 0x0018, 0xc4b: 0x0018,
+	0xc4c: 0x0018, 0xc4d: 0x0018, 0xc4e: 0x0008, 0xc4f: 0x0018, 0xc50: 0x2121, 0xc51: 0x2151,
+	0xc52: 0x2181, 0xc53: 0x21b9, 0xc54: 0x21e9, 0xc55: 0x2219, 0xc56: 0x2249, 0xc57: 0x2279,
+	0xc58: 0x22a9, 0xc59: 0x22d9, 0xc5a: 0x2309, 0xc5b: 0x2339, 0xc5c: 0x2369, 0xc5d: 0x2399,
+	0xc5e: 0x23c9, 0xc5f: 0x23f9, 0xc60: 0x0f41, 0xc61: 0x2421, 0xc62: 0x0905, 0xc63: 0x2439,
+	0xc64: 0x1089, 0xc65: 0x2451, 0xc66: 0x0925, 0xc67: 0x2469, 0xc68: 0x2491, 0xc69: 0x0369,
+	0xc6a: 0x24a9, 0xc6b: 0x0945, 0xc6c: 0x0359, 0xc6d: 0x1159, 0xc6e: 0x0ef9, 0xc6f: 0x0f61,
+	0xc70: 0x0f41, 0xc71: 0x2421, 0xc72: 0x0965, 0xc73: 0x2439, 0xc74: 0x1089, 0xc75: 0x2451,
+	0xc76: 0x0985, 0xc77: 0x2469, 0xc78: 0x2491, 0xc79: 0x0369, 0xc7a: 0x24a9, 0xc7b: 0x09a5,
+	0xc7c: 0x0359, 0xc7d: 0x1159, 0xc7e: 0x0ef9, 0xc7f: 0x0f61,
+	// Block 0x32, offset 0xc80
+	0xc80: 0x0018, 0xc81: 0x0018, 0xc82: 0x0018, 0xc83: 0x0018, 0xc84: 0x0018, 0xc85: 0x0018,
+	0xc86: 0x0018, 0xc87: 0x0018, 0xc88: 0x0018, 0xc89: 0x0018, 0xc8a: 0x0018, 0xc8b: 0x0040,
+	0xc8c: 0x0040, 0xc8d: 0x0040, 0xc8e: 0x0040, 0xc8f: 0x0040, 0xc90: 0x0040, 0xc91: 0x0040,
+	0xc92: 0x0040, 0xc93: 0x0040, 0xc94: 0x0040, 0xc95: 0x0040, 0xc96: 0x0040, 0xc97: 0x0040,
+	0xc98: 0x0040, 0xc99: 0x0040, 0xc9a: 0x0040, 0xc9b: 0x0040, 0xc9c: 0x0040, 0xc9d: 0x0040,
+	0xc9e: 0x0040, 0xc9f: 0x0040, 0xca0: 0x00c9, 0xca1: 0x0069, 0xca2: 0x0079, 0xca3: 0x1f51,
+	0xca4: 0x1f61, 0xca5: 0x1f71, 0xca6: 0x1f81, 0xca7: 0x1f91, 0xca8: 0x1fa1, 0xca9: 0x2601,
+	0xcaa: 0x2619, 0xcab: 0x2631, 0xcac: 0x2649, 0xcad: 0x2661, 0xcae: 0x2679, 0xcaf: 0x2691,
+	0xcb0: 0x26a9, 0xcb1: 0x26c1, 0xcb2: 0x26d9, 0xcb3: 0x26f1, 0xcb4: 0x0a06, 0xcb5: 0x0a26,
+	0xcb6: 0x0a46, 0xcb7: 0x0a66, 0xcb8: 0x0a86, 0xcb9: 0x0aa6, 0xcba: 0x0ac6, 0xcbb: 0x0ae6,
+	0xcbc: 0x0b06, 0xcbd: 0x270a, 0xcbe: 0x2732, 0xcbf: 0x275a,
+	// Block 0x33, offset 0xcc0
+	0xcc0: 0x2782, 0xcc1: 0x27aa, 0xcc2: 0x27d2, 0xcc3: 0x27fa, 0xcc4: 0x2822, 0xcc5: 0x284a,
+	0xcc6: 0x2872, 0xcc7: 0x289a, 0xcc8: 0x0040, 0xcc9: 0x0040, 0xcca: 0x0040, 0xccb: 0x0040,
+	0xccc: 0x0040, 0xccd: 0x0040, 0xcce: 0x0040, 0xccf: 0x0040, 0xcd0: 0x0040, 0xcd1: 0x0040,
+	0xcd2: 0x0040, 0xcd3: 0x0040, 0xcd4: 0x0040, 0xcd5: 0x0040, 0xcd6: 0x0040, 0xcd7: 0x0040,
+	0xcd8: 0x0040, 0xcd9: 0x0040, 0xcda: 0x0040, 0xcdb: 0x0040, 0xcdc: 0x0b26, 0xcdd: 0x0b46,
+	0xcde: 0x0b66, 0xcdf: 0x0b86, 0xce0: 0x0ba6, 0xce1: 0x0bc6, 0xce2: 0x0be6, 0xce3: 0x0c06,
+	0xce4: 0x0c26, 0xce5: 0x0c46, 0xce6: 0x0c66, 0xce7: 0x0c86, 0xce8: 0x0ca6, 0xce9: 0x0cc6,
+	0xcea: 0x0ce6, 0xceb: 0x0d06, 0xcec: 0x0d26, 0xced: 0x0d46, 0xcee: 0x0d66, 0xcef: 0x0d86,
+	0xcf0: 0x0da6, 0xcf1: 0x0dc6, 0xcf2: 0x0de6, 0xcf3: 0x0e06, 0xcf4: 0x0e26, 0xcf5: 0x0e46,
+	0xcf6: 0x0039, 0xcf7: 0x0ee9, 0xcf8: 0x1159, 0xcf9: 0x0ef9, 0xcfa: 0x0f09, 0xcfb: 0x1199,
+	0xcfc: 0x0f31, 0xcfd: 0x0249, 0xcfe: 0x0f41, 0xcff: 0x0259,
+	// Block 0x34, offset 0xd00
+	0xd00: 0x0f51, 0xd01: 0x0359, 0xd02: 0x0f61, 0xd03: 0x0f71, 0xd04: 0x00d9, 0xd05: 0x0f99,
+	0xd06: 0x2039, 0xd07: 0x0269, 0xd08: 0x01d9, 0xd09: 0x0fa9, 0xd0a: 0x0fb9, 0xd0b: 0x1089,
+	0xd0c: 0x0279, 0xd0d: 0x0369, 0xd0e: 0x0289, 0xd0f: 0x13d1, 0xd10: 0x0039, 0xd11: 0x0ee9,
+	0xd12: 0x1159, 0xd13: 0x0ef9, 0xd14: 0x0f09, 0xd15: 0x1199, 0xd16: 0x0f31, 0xd17: 0x0249,
+	0xd18: 0x0f41, 0xd19: 0x0259, 0xd1a: 0x0f51, 0xd1b: 0x0359, 0xd1c: 0x0f61, 0xd1d: 0x0f71,
+	0xd1e: 0x00d9, 0xd1f: 0x0f99, 0xd20: 0x2039, 0xd21: 0x0269, 0xd22: 0x01d9, 0xd23: 0x0fa9,
+	0xd24: 0x0fb9, 0xd25: 0x1089, 0xd26: 0x0279, 0xd27: 0x0369, 0xd28: 0x0289, 0xd29: 0x13d1,
+	0xd2a: 0x1f41, 0xd2b: 0x0018, 0xd2c: 0x0018, 0xd2d: 0x0018, 0xd2e: 0x0018, 0xd2f: 0x0018,
+	0xd30: 0x0018, 0xd31: 0x0018, 0xd32: 0x0018, 0xd33: 0x0018, 0xd34: 0x0018, 0xd35: 0x0018,
+	0xd36: 0x0018, 0xd37: 0x0018, 0xd38: 0x0018, 0xd39: 0x0018, 0xd3a: 0x0018, 0xd3b: 0x0018,
+	0xd3c: 0x0018, 0xd3d: 0x0018, 0xd3e: 0x0018, 0xd3f: 0x0018,
+	// Block 0x35, offset 0xd40
+	0xd40: 0x0008, 0xd41: 0x0008, 0xd42: 0x0008, 0xd43: 0x0008, 0xd44: 0x0008, 0xd45: 0x0008,
+	0xd46: 0x0008, 0xd47: 0x0008, 0xd48: 0x0008, 0xd49: 0x0008, 0xd4a: 0x0008, 0xd4b: 0x0008,
+	0xd4c: 0x0008, 0xd4d: 0x0008, 0xd4e: 0x0008, 0xd4f: 0x0008, 0xd50: 0x0008, 0xd51: 0x0008,
+	0xd52: 0x0008, 0xd53: 0x0008, 0xd54: 0x0008, 0xd55: 0x0008, 0xd56: 0x0008, 0xd57: 0x0008,
+	0xd58: 0x0008, 0xd59: 0x0008, 0xd5a: 0x0008, 0xd5b: 0x0008, 0xd5c: 0x0008, 0xd5d: 0x0008,
+	0xd5e: 0x0008, 0xd5f: 0x0040, 0xd60: 0xe00d, 0xd61: 0x0008, 0xd62: 0x2971, 0xd63: 0x0ebd,
+	0xd64: 0x2989, 0xd65: 0x0008, 0xd66: 0x0008, 0xd67: 0xe07d, 0xd68: 0x0008, 0xd69: 0xe01d,
+	0xd6a: 0x0008, 0xd6b: 0xe03d, 0xd6c: 0x0008, 0xd6d: 0x0fe1, 0xd6e: 0x1281, 0xd6f: 0x0fc9,
+	0xd70: 0x1141, 0xd71: 0x0008, 0xd72: 0xe00d, 0xd73: 0x0008, 0xd74: 0x0008, 0xd75: 0xe01d,
+	0xd76: 0x0008, 0xd77: 0x0008, 0xd78: 0x0008, 0xd79: 0x0008, 0xd7a: 0x0008, 0xd7b: 0x0008,
+	0xd7c: 0x0259, 0xd7d: 0x1089, 0xd7e: 0x29a1, 0xd7f: 0x29b9,
+	// Block 0x36, offset 0xd80
+	0xd80: 0xe00d, 0xd81: 0x0008, 0xd82: 0xe00d, 0xd83: 0x0008, 0xd84: 0xe00d, 0xd85: 0x0008,
+	0xd86: 0xe00d, 0xd87: 0x0008, 0xd88: 0xe00d, 0xd89: 0x0008, 0xd8a: 0xe00d, 0xd8b: 0x0008,
+	0xd8c: 0xe00d, 0xd8d: 0x0008, 0xd8e: 0xe00d, 0xd8f: 0x0008, 0xd90: 0xe00d, 0xd91: 0x0008,
+	0xd92: 0xe00d, 0xd93: 0x0008, 0xd94: 0xe00d, 0xd95: 0x0008, 0xd96: 0xe00d, 0xd97: 0x0008,
+	0xd98: 0xe00d, 0xd99: 0x0008, 0xd9a: 0xe00d, 0xd9b: 0x0008, 0xd9c: 0xe00d, 0xd9d: 0x0008,
+	0xd9e: 0xe00d, 0xd9f: 0x0008, 0xda0: 0xe00d, 0xda1: 0x0008, 0xda2: 0xe00d, 0xda3: 0x0008,
+	0xda4: 0x0008, 0xda5: 0x0018, 0xda6: 0x0018, 0xda7: 0x0018, 0xda8: 0x0018, 0xda9: 0x0018,
+	0xdaa: 0x0018, 0xdab: 0xe03d, 0xdac: 0x0008, 0xdad: 0xe01d, 0xdae: 0x0008, 0xdaf: 0x1308,
+	0xdb0: 0x1308, 0xdb1: 0x1308, 0xdb2: 0xe00d, 0xdb3: 0x0008, 0xdb4: 0x0040, 0xdb5: 0x0040,
+	0xdb6: 0x0040, 0xdb7: 0x0040, 0xdb8: 0x0040, 0xdb9: 0x0018, 0xdba: 0x0018, 0xdbb: 0x0018,
+	0xdbc: 0x0018, 0xdbd: 0x0018, 0xdbe: 0x0018, 0xdbf: 0x0018,
+	// Block 0x37, offset 0xdc0
+	0xdc0: 0x26fd, 0xdc1: 0x271d, 0xdc2: 0x273d, 0xdc3: 0x275d, 0xdc4: 0x277d, 0xdc5: 0x279d,
+	0xdc6: 0x27bd, 0xdc7: 0x27dd, 0xdc8: 0x27fd, 0xdc9: 0x281d, 0xdca: 0x283d, 0xdcb: 0x285d,
+	0xdcc: 0x287d, 0xdcd: 0x289d, 0xdce: 0x28bd, 0xdcf: 0x28dd, 0xdd0: 0x28fd, 0xdd1: 0x291d,
+	0xdd2: 0x293d, 0xdd3: 0x295d, 0xdd4: 0x297d, 0xdd5: 0x299d, 0xdd6: 0x0040, 0xdd7: 0x0040,
+	0xdd8: 0x0040, 0xdd9: 0x0040, 0xdda: 0x0040, 0xddb: 0x0040, 0xddc: 0x0040, 0xddd: 0x0040,
+	0xdde: 0x0040, 0xddf: 0x0040, 0xde0: 0x0040, 0xde1: 0x0040, 0xde2: 0x0040, 0xde3: 0x0040,
+	0xde4: 0x0040, 0xde5: 0x0040, 0xde6: 0x0040, 0xde7: 0x0040, 0xde8: 0x0040, 0xde9: 0x0040,
+	0xdea: 0x0040, 0xdeb: 0x0040, 0xdec: 0x0040, 0xded: 0x0040, 0xdee: 0x0040, 0xdef: 0x0040,
+	0xdf0: 0x0040, 0xdf1: 0x0040, 0xdf2: 0x0040, 0xdf3: 0x0040, 0xdf4: 0x0040, 0xdf5: 0x0040,
+	0xdf6: 0x0040, 0xdf7: 0x0040, 0xdf8: 0x0040, 0xdf9: 0x0040, 0xdfa: 0x0040, 0xdfb: 0x0040,
+	0xdfc: 0x0040, 0xdfd: 0x0040, 0xdfe: 0x0040, 0xdff: 0x0040,
+	// Block 0x38, offset 0xe00
+	0xe00: 0x000a, 0xe01: 0x0018, 0xe02: 0x29d1, 0xe03: 0x0018, 0xe04: 0x0018, 0xe05: 0x0008,
+	0xe06: 0x0008, 0xe07: 0x0008, 0xe08: 0x0018, 0xe09: 0x0018, 0xe0a: 0x0018, 0xe0b: 0x0018,
+	0xe0c: 0x0018, 0xe0d: 0x0018, 0xe0e: 0x0018, 0xe0f: 0x0018, 0xe10: 0x0018, 0xe11: 0x0018,
+	0xe12: 0x0018, 0xe13: 0x0018, 0xe14: 0x0018, 0xe15: 0x0018, 0xe16: 0x0018, 0xe17: 0x0018,
+	0xe18: 0x0018, 0xe19: 0x0018, 0xe1a: 0x0018, 0xe1b: 0x0018, 0xe1c: 0x0018, 0xe1d: 0x0018,
+	0xe1e: 0x0018, 0xe1f: 0x0018, 0xe20: 0x0018, 0xe21: 0x0018, 0xe22: 0x0018, 0xe23: 0x0018,
+	0xe24: 0x0018, 0xe25: 0x0018, 0xe26: 0x0018, 0xe27: 0x0018, 0xe28: 0x0018, 0xe29: 0x0018,
+	0xe2a: 0x1308, 0xe2b: 0x1308, 0xe2c: 0x1308, 0xe2d: 0x1308, 0xe2e: 0x1018, 0xe2f: 0x1018,
+	0xe30: 0x0018, 0xe31: 0x0018, 0xe32: 0x0018, 0xe33: 0x0018, 0xe34: 0x0018, 0xe35: 0x0018,
+	0xe36: 0xe125, 0xe37: 0x0018, 0xe38: 0x29bd, 0xe39: 0x29dd, 0xe3a: 0x29fd, 0xe3b: 0x0018,
+	0xe3c: 0x0008, 0xe3d: 0x0018, 0xe3e: 0x0018, 0xe3f: 0x0018,
+	// Block 0x39, offset 0xe40
+	0xe40: 0x2b3d, 0xe41: 0x2b5d, 0xe42: 0x2b7d, 0xe43: 0x2b9d, 0xe44: 0x2bbd, 0xe45: 0x2bdd,
+	0xe46: 0x2bdd, 0xe47: 0x2bdd, 0xe48: 0x2bfd, 0xe49: 0x2bfd, 0xe4a: 0x2bfd, 0xe4b: 0x2bfd,
+	0xe4c: 0x2c1d, 0xe4d: 0x2c1d, 0xe4e: 0x2c1d, 0xe4f: 0x2c3d, 0xe50: 0x2c5d, 0xe51: 0x2c5d,
+	0xe52: 0x2a7d, 0xe53: 0x2a7d, 0xe54: 0x2c5d, 0xe55: 0x2c5d, 0xe56: 0x2c7d, 0xe57: 0x2c7d,
+	0xe58: 0x2c5d, 0xe59: 0x2c5d, 0xe5a: 0x2a7d, 0xe5b: 0x2a7d, 0xe5c: 0x2c5d, 0xe5d: 0x2c5d,
+	0xe5e: 0x2c3d, 0xe5f: 0x2c3d, 0xe60: 0x2c9d, 0xe61: 0x2c9d, 0xe62: 0x2cbd, 0xe63: 0x2cbd,
+	0xe64: 0x0040, 0xe65: 0x2cdd, 0xe66: 0x2cfd, 0xe67: 0x2d1d, 0xe68: 0x2d1d, 0xe69: 0x2d3d,
+	0xe6a: 0x2d5d, 0xe6b: 0x2d7d, 0xe6c: 0x2d9d, 0xe6d: 0x2dbd, 0xe6e: 0x2ddd, 0xe6f: 0x2dfd,
+	0xe70: 0x2e1d, 0xe71: 0x2e3d, 0xe72: 0x2e3d, 0xe73: 0x2e5d, 0xe74: 0x2e7d, 0xe75: 0x2e7d,
+	0xe76: 0x2e9d, 0xe77: 0x2ebd, 0xe78: 0x2e5d, 0xe79: 0x2edd, 0xe7a: 0x2efd, 0xe7b: 0x2edd,
+	0xe7c: 0x2e5d, 0xe7d: 0x2f1d, 0xe7e: 0x2f3d, 0xe7f: 0x2f5d,
+	// Block 0x3a, offset 0xe80
+	0xe80: 0x2f7d, 0xe81: 0x2f9d, 0xe82: 0x2cfd, 0xe83: 0x2cdd, 0xe84: 0x2fbd, 0xe85: 0x2fdd,
+	0xe86: 0x2ffd, 0xe87: 0x301d, 0xe88: 0x303d, 0xe89: 0x305d, 0xe8a: 0x307d, 0xe8b: 0x309d,
+	0xe8c: 0x30bd, 0xe8d: 0x30dd, 0xe8e: 0x30fd, 0xe8f: 0x0040, 0xe90: 0x0018, 0xe91: 0x0018,
+	0xe92: 0x311d, 0xe93: 0x313d, 0xe94: 0x315d, 0xe95: 0x317d, 0xe96: 0x319d, 0xe97: 0x31bd,
+	0xe98: 0x31dd, 0xe99: 0x31fd, 0xe9a: 0x321d, 0xe9b: 0x323d, 0xe9c: 0x315d, 0xe9d: 0x325d,
+	0xe9e: 0x327d, 0xe9f: 0x329d, 0xea0: 0x0008, 0xea1: 0x0008, 0xea2: 0x0008, 0xea3: 0x0008,
+	0xea4: 0x0008, 0xea5: 0x0008, 0xea6: 0x0008, 0xea7: 0x0008, 0xea8: 0x0008, 0xea9: 0x0008,
+	0xeaa: 0x0008, 0xeab: 0x0008, 0xeac: 0x0008, 0xead: 0x0008, 0xeae: 0x0008, 0xeaf: 0x0008,
+	0xeb0: 0x0008, 0xeb1: 0x0008, 0xeb2: 0x0008, 0xeb3: 0x0008, 0xeb4: 0x0008, 0xeb5: 0x0008,
+	0xeb6: 0x0008, 0xeb7: 0x0008, 0xeb8: 0x0008, 0xeb9: 0x0008, 0xeba: 0x0008, 0xebb: 0x0040,
+	0xebc: 0x0040, 0xebd: 0x0040, 0xebe: 0x0040, 0xebf: 0x0040,
+	// Block 0x3b, offset 0xec0
+	0xec0: 0x36a2, 0xec1: 0x36d2, 0xec2: 0x3702, 0xec3: 0x3732, 0xec4: 0x32bd, 0xec5: 0x32dd,
+	0xec6: 0x32fd, 0xec7: 0x331d, 0xec8: 0x0018, 0xec9: 0x0018, 0xeca: 0x0018, 0xecb: 0x0018,
+	0xecc: 0x0018, 0xecd: 0x0018, 0xece: 0x0018, 0xecf: 0x0018, 0xed0: 0x333d, 0xed1: 0x3761,
+	0xed2: 0x3779, 0xed3: 0x3791, 0xed4: 0x37a9, 0xed5: 0x37c1, 0xed6: 0x37d9, 0xed7: 0x37f1,
+	0xed8: 0x3809, 0xed9: 0x3821, 0xeda: 0x3839, 0xedb: 0x3851, 0xedc: 0x3869, 0xedd: 0x3881,
+	0xede: 0x3899, 0xedf: 0x38b1, 0xee0: 0x335d, 0xee1: 0x337d, 0xee2: 0x339d, 0xee3: 0x33bd,
+	0xee4: 0x33dd, 0xee5: 0x33dd, 0xee6: 0x33fd, 0xee7: 0x341d, 0xee8: 0x343d, 0xee9: 0x345d,
+	0xeea: 0x347d, 0xeeb: 0x349d, 0xeec: 0x34bd, 0xeed: 0x34dd, 0xeee: 0x34fd, 0xeef: 0x351d,
+	0xef0: 0x353d, 0xef1: 0x355d, 0xef2: 0x357d, 0xef3: 0x359d, 0xef4: 0x35bd, 0xef5: 0x35dd,
+	0xef6: 0x35fd, 0xef7: 0x361d, 0xef8: 0x363d, 0xef9: 0x365d, 0xefa: 0x367d, 0xefb: 0x369d,
+	0xefc: 0x38c9, 0xefd: 0x3901, 0xefe: 0x36bd, 0xeff: 0x0018,
+	// Block 0x3c, offset 0xf00
+	0xf00: 0x36dd, 0xf01: 0x36fd, 0xf02: 0x371d, 0xf03: 0x373d, 0xf04: 0x375d, 0xf05: 0x377d,
+	0xf06: 0x379d, 0xf07: 0x37bd, 0xf08: 0x37dd, 0xf09: 0x37fd, 0xf0a: 0x381d, 0xf0b: 0x383d,
+	0xf0c: 0x385d, 0xf0d: 0x387d, 0xf0e: 0x389d, 0xf0f: 0x38bd, 0xf10: 0x38dd, 0xf11: 0x38fd,
+	0xf12: 0x391d, 0xf13: 0x393d, 0xf14: 0x395d, 0xf15: 0x397d, 0xf16: 0x399d, 0xf17: 0x39bd,
+	0xf18: 0x39dd, 0xf19: 0x39fd, 0xf1a: 0x3a1d, 0xf1b: 0x3a3d, 0xf1c: 0x3a5d, 0xf1d: 0x3a7d,
+	0xf1e: 0x3a9d, 0xf1f: 0x3abd, 0xf20: 0x3add, 0xf21: 0x3afd, 0xf22: 0x3b1d, 0xf23: 0x3b3d,
+	0xf24: 0x3b5d, 0xf25: 0x3b7d, 0xf26: 0x127d, 0xf27: 0x3b9d, 0xf28: 0x3bbd, 0xf29: 0x3bdd,
+	0xf2a: 0x3bfd, 0xf2b: 0x3c1d, 0xf2c: 0x3c3d, 0xf2d: 0x3c5d, 0xf2e: 0x239d, 0xf2f: 0x3c7d,
+	0xf30: 0x3c9d, 0xf31: 0x3939, 0xf32: 0x3951, 0xf33: 0x3969, 0xf34: 0x3981, 0xf35: 0x3999,
+	0xf36: 0x39b1, 0xf37: 0x39c9, 0xf38: 0x39e1, 0xf39: 0x39f9, 0xf3a: 0x3a11, 0xf3b: 0x3a29,
+	0xf3c: 0x3a41, 0xf3d: 0x3a59, 0xf3e: 0x3a71, 0xf3f: 0x3a89,
+	// Block 0x3d, offset 0xf40
+	0xf40: 0x3aa1, 0xf41: 0x3ac9, 0xf42: 0x3af1, 0xf43: 0x3b19, 0xf44: 0x3b41, 0xf45: 0x3b69,
+	0xf46: 0x3b91, 0xf47: 0x3bb9, 0xf48: 0x3be1, 0xf49: 0x3c09, 0xf4a: 0x3c39, 0xf4b: 0x3c69,
+	0xf4c: 0x3c99, 0xf4d: 0x3cbd, 0xf4e: 0x3cb1, 0xf4f: 0x3cdd, 0xf50: 0x3cfd, 0xf51: 0x3d15,
+	0xf52: 0x3d2d, 0xf53: 0x3d45, 0xf54: 0x3d5d, 0xf55: 0x3d5d, 0xf56: 0x3d45, 0xf57: 0x3d75,
+	0xf58: 0x07bd, 0xf59: 0x3d8d, 0xf5a: 0x3da5, 0xf5b: 0x3dbd, 0xf5c: 0x3dd5, 0xf5d: 0x3ded,
+	0xf5e: 0x3e05, 0xf5f: 0x3e1d, 0xf60: 0x3e35, 0xf61: 0x3e4d, 0xf62: 0x3e65, 0xf63: 0x3e7d,
+	0xf64: 0x3e95, 0xf65: 0x3e95, 0xf66: 0x3ead, 0xf67: 0x3ead, 0xf68: 0x3ec5, 0xf69: 0x3ec5,
+	0xf6a: 0x3edd, 0xf6b: 0x3ef5, 0xf6c: 0x3f0d, 0xf6d: 0x3f25, 0xf6e: 0x3f3d, 0xf6f: 0x3f3d,
+	0xf70: 0x3f55, 0xf71: 0x3f55, 0xf72: 0x3f55, 0xf73: 0x3f6d, 0xf74: 0x3f85, 0xf75: 0x3f9d,
+	0xf76: 0x3fb5, 0xf77: 0x3f9d, 0xf78: 0x3fcd, 0xf79: 0x3fe5, 0xf7a: 0x3f6d, 0xf7b: 0x3ffd,
+	0xf7c: 0x4015, 0xf7d: 0x4015, 0xf7e: 0x4015, 0xf7f: 0x0040,
+	// Block 0x3e, offset 0xf80
+	0xf80: 0x3cc9, 0xf81: 0x3d31, 0xf82: 0x3d99, 0xf83: 0x3e01, 0xf84: 0x3e51, 0xf85: 0x3eb9,
+	0xf86: 0x3f09, 0xf87: 0x3f59, 0xf88: 0x3fd9, 0xf89: 0x4041, 0xf8a: 0x4091, 0xf8b: 0x40e1,
+	0xf8c: 0x4131, 0xf8d: 0x4199, 0xf8e: 0x4201, 0xf8f: 0x4251, 0xf90: 0x42a1, 0xf91: 0x42d9,
+	0xf92: 0x4329, 0xf93: 0x4391, 0xf94: 0x43f9, 0xf95: 0x4431, 0xf96: 0x44b1, 0xf97: 0x4549,
+	0xf98: 0x45c9, 0xf99: 0x4619, 0xf9a: 0x4699, 0xf9b: 0x4719, 0xf9c: 0x4781, 0xf9d: 0x47d1,
+	0xf9e: 0x4821, 0xf9f: 0x4871, 0xfa0: 0x48d9, 0xfa1: 0x4959, 0xfa2: 0x49c1, 0xfa3: 0x4a11,
+	0xfa4: 0x4a61, 0xfa5: 0x4ab1, 0xfa6: 0x4ae9, 0xfa7: 0x4b21, 0xfa8: 0x4b59, 0xfa9: 0x4b91,
+	0xfaa: 0x4be1, 0xfab: 0x4c31, 0xfac: 0x4cb1, 0xfad: 0x4d01, 0xfae: 0x4d69, 0xfaf: 0x4de9,
+	0xfb0: 0x4e39, 0xfb1: 0x4e71, 0xfb2: 0x4ea9, 0xfb3: 0x4f29, 0xfb4: 0x4f91, 0xfb5: 0x5011,
+	0xfb6: 0x5061, 0xfb7: 0x50e1, 0xfb8: 0x5119, 0xfb9: 0x5169, 0xfba: 0x51b9, 0xfbb: 0x5209,
+	0xfbc: 0x5259, 0xfbd: 0x52a9, 0xfbe: 0x5311, 0xfbf: 0x5361,
+	// Block 0x3f, offset 0xfc0
+	0xfc0: 0x5399, 0xfc1: 0x53e9, 0xfc2: 0x5439, 0xfc3: 0x5489, 0xfc4: 0x54f1, 0xfc5: 0x5541,
+	0xfc6: 0x5591, 0xfc7: 0x55e1, 0xfc8: 0x5661, 0xfc9: 0x56c9, 0xfca: 0x5701, 0xfcb: 0x5781,
+	0xfcc: 0x57b9, 0xfcd: 0x5821, 0xfce: 0x5889, 0xfcf: 0x58d9, 0xfd0: 0x5929, 0xfd1: 0x5979,
+	0xfd2: 0x59e1, 0xfd3: 0x5a19, 0xfd4: 0x5a69, 0xfd5: 0x5ad1, 0xfd6: 0x5b09, 0xfd7: 0x5b89,
+	0xfd8: 0x5bd9, 0xfd9: 0x5c01, 0xfda: 0x5c29, 0xfdb: 0x5c51, 0xfdc: 0x5c79, 0xfdd: 0x5ca1,
+	0xfde: 0x5cc9, 0xfdf: 0x5cf1, 0xfe0: 0x5d19, 0xfe1: 0x5d41, 0xfe2: 0x5d69, 0xfe3: 0x5d99,
+	0xfe4: 0x5dc9, 0xfe5: 0x5df9, 0xfe6: 0x5e29, 0xfe7: 0x5e59, 0xfe8: 0x5e89, 0xfe9: 0x5eb9,
+	0xfea: 0x5ee9, 0xfeb: 0x5f19, 0xfec: 0x5f49, 0xfed: 0x5f79, 0xfee: 0x5fa9, 0xfef: 0x5fd9,
+	0xff0: 0x6009, 0xff1: 0x402d, 0xff2: 0x6039, 0xff3: 0x6051, 0xff4: 0x404d, 0xff5: 0x6069,
+	0xff6: 0x6081, 0xff7: 0x6099, 0xff8: 0x406d, 0xff9: 0x406d, 0xffa: 0x60b1, 0xffb: 0x60c9,
+	0xffc: 0x6101, 0xffd: 0x6139, 0xffe: 0x6171, 0xfff: 0x61a9,
+	// Block 0x40, offset 0x1000
+	0x1000: 0x6211, 0x1001: 0x6229, 0x1002: 0x408d, 0x1003: 0x6241, 0x1004: 0x6259, 0x1005: 0x6271,
+	0x1006: 0x6289, 0x1007: 0x62a1, 0x1008: 0x40ad, 0x1009: 0x62b9, 0x100a: 0x62e1, 0x100b: 0x62f9,
+	0x100c: 0x40cd, 0x100d: 0x40cd, 0x100e: 0x6311, 0x100f: 0x6329, 0x1010: 0x6341, 0x1011: 0x40ed,
+	0x1012: 0x410d, 0x1013: 0x412d, 0x1014: 0x414d, 0x1015: 0x416d, 0x1016: 0x6359, 0x1017: 0x6371,
+	0x1018: 0x6389, 0x1019: 0x63a1, 0x101a: 0x63b9, 0x101b: 0x418d, 0x101c: 0x63d1, 0x101d: 0x63e9,
+	0x101e: 0x6401, 0x101f: 0x41ad, 0x1020: 0x41cd, 0x1021: 0x6419, 0x1022: 0x41ed, 0x1023: 0x420d,
+	0x1024: 0x422d, 0x1025: 0x6431, 0x1026: 0x424d, 0x1027: 0x6449, 0x1028: 0x6479, 0x1029: 0x6211,
+	0x102a: 0x426d, 0x102b: 0x428d, 0x102c: 0x42ad, 0x102d: 0x42cd, 0x102e: 0x64b1, 0x102f: 0x64f1,
+	0x1030: 0x6539, 0x1031: 0x6551, 0x1032: 0x42ed, 0x1033: 0x6569, 0x1034: 0x6581, 0x1035: 0x6599,
+	0x1036: 0x430d, 0x1037: 0x65b1, 0x1038: 0x65c9, 0x1039: 0x65b1, 0x103a: 0x65e1, 0x103b: 0x65f9,
+	0x103c: 0x432d, 0x103d: 0x6611, 0x103e: 0x6629, 0x103f: 0x6611,
+	// Block 0x41, offset 0x1040
+	0x1040: 0x434d, 0x1041: 0x436d, 0x1042: 0x0040, 0x1043: 0x6641, 0x1044: 0x6659, 0x1045: 0x6671,
+	0x1046: 0x6689, 0x1047: 0x0040, 0x1048: 0x66c1, 0x1049: 0x66d9, 0x104a: 0x66f1, 0x104b: 0x6709,
+	0x104c: 0x6721, 0x104d: 0x6739, 0x104e: 0x6401, 0x104f: 0x6751, 0x1050: 0x6769, 0x1051: 0x6781,
+	0x1052: 0x438d, 0x1053: 0x6799, 0x1054: 0x6289, 0x1055: 0x43ad, 0x1056: 0x43cd, 0x1057: 0x67b1,
+	0x1058: 0x0040, 0x1059: 0x43ed, 0x105a: 0x67c9, 0x105b: 0x67e1, 0x105c: 0x67f9, 0x105d: 0x6811,
+	0x105e: 0x6829, 0x105f: 0x6859, 0x1060: 0x6889, 0x1061: 0x68b1, 0x1062: 0x68d9, 0x1063: 0x6901,
+	0x1064: 0x6929, 0x1065: 0x6951, 0x1066: 0x6979, 0x1067: 0x69a1, 0x1068: 0x69c9, 0x1069: 0x69f1,
+	0x106a: 0x6a21, 0x106b: 0x6a51, 0x106c: 0x6a81, 0x106d: 0x6ab1, 0x106e: 0x6ae1, 0x106f: 0x6b11,
+	0x1070: 0x6b41, 0x1071: 0x6b71, 0x1072: 0x6ba1, 0x1073: 0x6bd1, 0x1074: 0x6c01, 0x1075: 0x6c31,
+	0x1076: 0x6c61, 0x1077: 0x6c91, 0x1078: 0x6cc1, 0x1079: 0x6cf1, 0x107a: 0x6d21, 0x107b: 0x6d51,
+	0x107c: 0x6d81, 0x107d: 0x6db1, 0x107e: 0x6de1, 0x107f: 0x440d,
+	// Block 0x42, offset 0x1080
+	0x1080: 0xe00d, 0x1081: 0x0008, 0x1082: 0xe00d, 0x1083: 0x0008, 0x1084: 0xe00d, 0x1085: 0x0008,
+	0x1086: 0xe00d, 0x1087: 0x0008, 0x1088: 0xe00d, 0x1089: 0x0008, 0x108a: 0xe00d, 0x108b: 0x0008,
+	0x108c: 0xe00d, 0x108d: 0x0008, 0x108e: 0xe00d, 0x108f: 0x0008, 0x1090: 0xe00d, 0x1091: 0x0008,
+	0x1092: 0xe00d, 0x1093: 0x0008, 0x1094: 0xe00d, 0x1095: 0x0008, 0x1096: 0xe00d, 0x1097: 0x0008,
+	0x1098: 0xe00d, 0x1099: 0x0008, 0x109a: 0xe00d, 0x109b: 0x0008, 0x109c: 0xe00d, 0x109d: 0x0008,
+	0x109e: 0xe00d, 0x109f: 0x0008, 0x10a0: 0xe00d, 0x10a1: 0x0008, 0x10a2: 0xe00d, 0x10a3: 0x0008,
+	0x10a4: 0xe00d, 0x10a5: 0x0008, 0x10a6: 0xe00d, 0x10a7: 0x0008, 0x10a8: 0xe00d, 0x10a9: 0x0008,
+	0x10aa: 0xe00d, 0x10ab: 0x0008, 0x10ac: 0xe00d, 0x10ad: 0x0008, 0x10ae: 0x0008, 0x10af: 0x1308,
+	0x10b0: 0x1318, 0x10b1: 0x1318, 0x10b2: 0x1318, 0x10b3: 0x0018, 0x10b4: 0x1308, 0x10b5: 0x1308,
+	0x10b6: 0x1308, 0x10b7: 0x1308, 0x10b8: 0x1308, 0x10b9: 0x1308, 0x10ba: 0x1308, 0x10bb: 0x1308,
+	0x10bc: 0x1308, 0x10bd: 0x1308, 0x10be: 0x0018, 0x10bf: 0x0008,
+	// Block 0x43, offset 0x10c0
+	0x10c0: 0xe00d, 0x10c1: 0x0008, 0x10c2: 0xe00d, 0x10c3: 0x0008, 0x10c4: 0xe00d, 0x10c5: 0x0008,
+	0x10c6: 0xe00d, 0x10c7: 0x0008, 0x10c8: 0xe00d, 0x10c9: 0x0008, 0x10ca: 0xe00d, 0x10cb: 0x0008,
+	0x10cc: 0xe00d, 0x10cd: 0x0008, 0x10ce: 0xe00d, 0x10cf: 0x0008, 0x10d0: 0xe00d, 0x10d1: 0x0008,
+	0x10d2: 0xe00d, 0x10d3: 0x0008, 0x10d4: 0xe00d, 0x10d5: 0x0008, 0x10d6: 0xe00d, 0x10d7: 0x0008,
+	0x10d8: 0xe00d, 0x10d9: 0x0008, 0x10da: 0xe00d, 0x10db: 0x0008, 0x10dc: 0x0ea1, 0x10dd: 0x6e11,
+	0x10de: 0x1308, 0x10df: 0x1308, 0x10e0: 0x0008, 0x10e1: 0x0008, 0x10e2: 0x0008, 0x10e3: 0x0008,
+	0x10e4: 0x0008, 0x10e5: 0x0008, 0x10e6: 0x0008, 0x10e7: 0x0008, 0x10e8: 0x0008, 0x10e9: 0x0008,
+	0x10ea: 0x0008, 0x10eb: 0x0008, 0x10ec: 0x0008, 0x10ed: 0x0008, 0x10ee: 0x0008, 0x10ef: 0x0008,
+	0x10f0: 0x0008, 0x10f1: 0x0008, 0x10f2: 0x0008, 0x10f3: 0x0008, 0x10f4: 0x0008, 0x10f5: 0x0008,
+	0x10f6: 0x0008, 0x10f7: 0x0008, 0x10f8: 0x0008, 0x10f9: 0x0008, 0x10fa: 0x0008, 0x10fb: 0x0008,
+	0x10fc: 0x0008, 0x10fd: 0x0008, 0x10fe: 0x0008, 0x10ff: 0x0008,
+	// Block 0x44, offset 0x1100
+	0x1100: 0x0018, 0x1101: 0x0018, 0x1102: 0x0018, 0x1103: 0x0018, 0x1104: 0x0018, 0x1105: 0x0018,
+	0x1106: 0x0018, 0x1107: 0x0018, 0x1108: 0x0018, 0x1109: 0x0018, 0x110a: 0x0018, 0x110b: 0x0018,
+	0x110c: 0x0018, 0x110d: 0x0018, 0x110e: 0x0018, 0x110f: 0x0018, 0x1110: 0x0018, 0x1111: 0x0018,
+	0x1112: 0x0018, 0x1113: 0x0018, 0x1114: 0x0018, 0x1115: 0x0018, 0x1116: 0x0018, 0x1117: 0x0008,
+	0x1118: 0x0008, 0x1119: 0x0008, 0x111a: 0x0008, 0x111b: 0x0008, 0x111c: 0x0008, 0x111d: 0x0008,
+	0x111e: 0x0008, 0x111f: 0x0008, 0x1120: 0x0018, 0x1121: 0x0018, 0x1122: 0xe00d, 0x1123: 0x0008,
+	0x1124: 0xe00d, 0x1125: 0x0008, 0x1126: 0xe00d, 0x1127: 0x0008, 0x1128: 0xe00d, 0x1129: 0x0008,
+	0x112a: 0xe00d, 0x112b: 0x0008, 0x112c: 0xe00d, 0x112d: 0x0008, 0x112e: 0xe00d, 0x112f: 0x0008,
+	0x1130: 0x0008, 0x1131: 0x0008, 0x1132: 0xe00d, 0x1133: 0x0008, 0x1134: 0xe00d, 0x1135: 0x0008,
+	0x1136: 0xe00d, 0x1137: 0x0008, 0x1138: 0xe00d, 0x1139: 0x0008, 0x113a: 0xe00d, 0x113b: 0x0008,
+	0x113c: 0xe00d, 0x113d: 0x0008, 0x113e: 0xe00d, 0x113f: 0x0008,
+	// Block 0x45, offset 0x1140
+	0x1140: 0xe00d, 0x1141: 0x0008, 0x1142: 0xe00d, 0x1143: 0x0008, 0x1144: 0xe00d, 0x1145: 0x0008,
+	0x1146: 0xe00d, 0x1147: 0x0008, 0x1148: 0xe00d, 0x1149: 0x0008, 0x114a: 0xe00d, 0x114b: 0x0008,
+	0x114c: 0xe00d, 0x114d: 0x0008, 0x114e: 0xe00d, 0x114f: 0x0008, 0x1150: 0xe00d, 0x1151: 0x0008,
+	0x1152: 0xe00d, 0x1153: 0x0008, 0x1154: 0xe00d, 0x1155: 0x0008, 0x1156: 0xe00d, 0x1157: 0x0008,
+	0x1158: 0xe00d, 0x1159: 0x0008, 0x115a: 0xe00d, 0x115b: 0x0008, 0x115c: 0xe00d, 0x115d: 0x0008,
+	0x115e: 0xe00d, 0x115f: 0x0008, 0x1160: 0xe00d, 0x1161: 0x0008, 0x1162: 0xe00d, 0x1163: 0x0008,
+	0x1164: 0xe00d, 0x1165: 0x0008, 0x1166: 0xe00d, 0x1167: 0x0008, 0x1168: 0xe00d, 0x1169: 0x0008,
+	0x116a: 0xe00d, 0x116b: 0x0008, 0x116c: 0xe00d, 0x116d: 0x0008, 0x116e: 0xe00d, 0x116f: 0x0008,
+	0x1170: 0xe0fd, 0x1171: 0x0008, 0x1172: 0x0008, 0x1173: 0x0008, 0x1174: 0x0008, 0x1175: 0x0008,
+	0x1176: 0x0008, 0x1177: 0x0008, 0x1178: 0x0008, 0x1179: 0xe01d, 0x117a: 0x0008, 0x117b: 0xe03d,
+	0x117c: 0x0008, 0x117d: 0x442d, 0x117e: 0xe00d, 0x117f: 0x0008,
+	// Block 0x46, offset 0x1180
+	0x1180: 0xe00d, 0x1181: 0x0008, 0x1182: 0xe00d, 0x1183: 0x0008, 0x1184: 0xe00d, 0x1185: 0x0008,
+	0x1186: 0xe00d, 0x1187: 0x0008, 0x1188: 0x0008, 0x1189: 0x0018, 0x118a: 0x0018, 0x118b: 0xe03d,
+	0x118c: 0x0008, 0x118d: 0x11d9, 0x118e: 0x0008, 0x118f: 0x0008, 0x1190: 0xe00d, 0x1191: 0x0008,
+	0x1192: 0xe00d, 0x1193: 0x0008, 0x1194: 0x0008, 0x1195: 0x0008, 0x1196: 0xe00d, 0x1197: 0x0008,
+	0x1198: 0xe00d, 0x1199: 0x0008, 0x119a: 0xe00d, 0x119b: 0x0008, 0x119c: 0xe00d, 0x119d: 0x0008,
+	0x119e: 0xe00d, 0x119f: 0x0008, 0x11a0: 0xe00d, 0x11a1: 0x0008, 0x11a2: 0xe00d, 0x11a3: 0x0008,
+	0x11a4: 0xe00d, 0x11a5: 0x0008, 0x11a6: 0xe00d, 0x11a7: 0x0008, 0x11a8: 0xe00d, 0x11a9: 0x0008,
+	0x11aa: 0x6e29, 0x11ab: 0x1029, 0x11ac: 0x11c1, 0x11ad: 0x6e41, 0x11ae: 0x1221, 0x11af: 0x0040,
+	0x11b0: 0x6e59, 0x11b1: 0x6e71, 0x11b2: 0x1239, 0x11b3: 0x444d, 0x11b4: 0xe00d, 0x11b5: 0x0008,
+	0x11b6: 0xe00d, 0x11b7: 0x0008, 0x11b8: 0x0040, 0x11b9: 0x0040, 0x11ba: 0x0040, 0x11bb: 0x0040,
+	0x11bc: 0x0040, 0x11bd: 0x0040, 0x11be: 0x0040, 0x11bf: 0x0040,
+	// Block 0x47, offset 0x11c0
+	0x11c0: 0x64d5, 0x11c1: 0x64f5, 0x11c2: 0x6515, 0x11c3: 0x6535, 0x11c4: 0x6555, 0x11c5: 0x6575,
+	0x11c6: 0x6595, 0x11c7: 0x65b5, 0x11c8: 0x65d5, 0x11c9: 0x65f5, 0x11ca: 0x6615, 0x11cb: 0x6635,
+	0x11cc: 0x6655, 0x11cd: 0x6675, 0x11ce: 0x0008, 0x11cf: 0x0008, 0x11d0: 0x6695, 0x11d1: 0x0008,
+	0x11d2: 0x66b5, 0x11d3: 0x0008, 0x11d4: 0x0008, 0x11d5: 0x66d5, 0x11d6: 0x66f5, 0x11d7: 0x6715,
+	0x11d8: 0x6735, 0x11d9: 0x6755, 0x11da: 0x6775, 0x11db: 0x6795, 0x11dc: 0x67b5, 0x11dd: 0x67d5,
+	0x11de: 0x67f5, 0x11df: 0x0008, 0x11e0: 0x6815, 0x11e1: 0x0008, 0x11e2: 0x6835, 0x11e3: 0x0008,
+	0x11e4: 0x0008, 0x11e5: 0x6855, 0x11e6: 0x6875, 0x11e7: 0x0008, 0x11e8: 0x0008, 0x11e9: 0x0008,
+	0x11ea: 0x6895, 0x11eb: 0x68b5, 0x11ec: 0x68d5, 0x11ed: 0x68f5, 0x11ee: 0x6915, 0x11ef: 0x6935,
+	0x11f0: 0x6955, 0x11f1: 0x6975, 0x11f2: 0x6995, 0x11f3: 0x69b5, 0x11f4: 0x69d5, 0x11f5: 0x69f5,
+	0x11f6: 0x6a15, 0x11f7: 0x6a35, 0x11f8: 0x6a55, 0x11f9: 0x6a75, 0x11fa: 0x6a95, 0x11fb: 0x6ab5,
+	0x11fc: 0x6ad5, 0x11fd: 0x6af5, 0x11fe: 0x6b15, 0x11ff: 0x6b35,
+	// Block 0x48, offset 0x1200
+	0x1200: 0x7a95, 0x1201: 0x7ab5, 0x1202: 0x7ad5, 0x1203: 0x7af5, 0x1204: 0x7b15, 0x1205: 0x7b35,
+	0x1206: 0x7b55, 0x1207: 0x7b75, 0x1208: 0x7b95, 0x1209: 0x7bb5, 0x120a: 0x7bd5, 0x120b: 0x7bf5,
+	0x120c: 0x7c15, 0x120d: 0x7c35, 0x120e: 0x7c55, 0x120f: 0x6ec9, 0x1210: 0x6ef1, 0x1211: 0x6f19,
+	0x1212: 0x7c75, 0x1213: 0x7c95, 0x1214: 0x7cb5, 0x1215: 0x6f41, 0x1216: 0x6f69, 0x1217: 0x6f91,
+	0x1218: 0x7cd5, 0x1219: 0x7cf5, 0x121a: 0x0040, 0x121b: 0x0040, 0x121c: 0x0040, 0x121d: 0x0040,
+	0x121e: 0x0040, 0x121f: 0x0040, 0x1220: 0x0040, 0x1221: 0x0040, 0x1222: 0x0040, 0x1223: 0x0040,
+	0x1224: 0x0040, 0x1225: 0x0040, 0x1226: 0x0040, 0x1227: 0x0040, 0x1228: 0x0040, 0x1229: 0x0040,
+	0x122a: 0x0040, 0x122b: 0x0040, 0x122c: 0x0040, 0x122d: 0x0040, 0x122e: 0x0040, 0x122f: 0x0040,
+	0x1230: 0x0040, 0x1231: 0x0040, 0x1232: 0x0040, 0x1233: 0x0040, 0x1234: 0x0040, 0x1235: 0x0040,
+	0x1236: 0x0040, 0x1237: 0x0040, 0x1238: 0x0040, 0x1239: 0x0040, 0x123a: 0x0040, 0x123b: 0x0040,
+	0x123c: 0x0040, 0x123d: 0x0040, 0x123e: 0x0040, 0x123f: 0x0040,
+	// Block 0x49, offset 0x1240
+	0x1240: 0x6fb9, 0x1241: 0x6fd1, 0x1242: 0x6fe9, 0x1243: 0x7d15, 0x1244: 0x7d35, 0x1245: 0x7001,
+	0x1246: 0x7001, 0x1247: 0x0040, 0x1248: 0x0040, 0x1249: 0x0040, 0x124a: 0x0040, 0x124b: 0x0040,
+	0x124c: 0x0040, 0x124d: 0x0040, 0x124e: 0x0040, 0x124f: 0x0040, 0x1250: 0x0040, 0x1251: 0x0040,
+	0x1252: 0x0040, 0x1253: 0x7019, 0x1254: 0x7041, 0x1255: 0x7069, 0x1256: 0x7091, 0x1257: 0x70b9,
+	0x1258: 0x0040, 0x1259: 0x0040, 0x125a: 0x0040, 0x125b: 0x0040, 0x125c: 0x0040, 0x125d: 0x70e1,
+	0x125e: 0x1308, 0x125f: 0x7109, 0x1260: 0x7131, 0x1261: 0x20a9, 0x1262: 0x20f1, 0x1263: 0x7149,
+	0x1264: 0x7161, 0x1265: 0x7179, 0x1266: 0x7191, 0x1267: 0x71a9, 0x1268: 0x71c1, 0x1269: 0x1fb2,
+	0x126a: 0x71d9, 0x126b: 0x7201, 0x126c: 0x7229, 0x126d: 0x7261, 0x126e: 0x7299, 0x126f: 0x72c1,
+	0x1270: 0x72e9, 0x1271: 0x7311, 0x1272: 0x7339, 0x1273: 0x7361, 0x1274: 0x7389, 0x1275: 0x73b1,
+	0x1276: 0x73d9, 0x1277: 0x0040, 0x1278: 0x7401, 0x1279: 0x7429, 0x127a: 0x7451, 0x127b: 0x7479,
+	0x127c: 0x74a1, 0x127d: 0x0040, 0x127e: 0x74c9, 0x127f: 0x0040,
+	// Block 0x4a, offset 0x1280
+	0x1280: 0x74f1, 0x1281: 0x7519, 0x1282: 0x0040, 0x1283: 0x7541, 0x1284: 0x7569, 0x1285: 0x0040,
+	0x1286: 0x7591, 0x1287: 0x75b9, 0x1288: 0x75e1, 0x1289: 0x7609, 0x128a: 0x7631, 0x128b: 0x7659,
+	0x128c: 0x7681, 0x128d: 0x76a9, 0x128e: 0x76d1, 0x128f: 0x76f9, 0x1290: 0x7721, 0x1291: 0x7721,
+	0x1292: 0x7739, 0x1293: 0x7739, 0x1294: 0x7739, 0x1295: 0x7739, 0x1296: 0x7751, 0x1297: 0x7751,
+	0x1298: 0x7751, 0x1299: 0x7751, 0x129a: 0x7769, 0x129b: 0x7769, 0x129c: 0x7769, 0x129d: 0x7769,
+	0x129e: 0x7781, 0x129f: 0x7781, 0x12a0: 0x7781, 0x12a1: 0x7781, 0x12a2: 0x7799, 0x12a3: 0x7799,
+	0x12a4: 0x7799, 0x12a5: 0x7799, 0x12a6: 0x77b1, 0x12a7: 0x77b1, 0x12a8: 0x77b1, 0x12a9: 0x77b1,
+	0x12aa: 0x77c9, 0x12ab: 0x77c9, 0x12ac: 0x77c9, 0x12ad: 0x77c9, 0x12ae: 0x77e1, 0x12af: 0x77e1,
+	0x12b0: 0x77e1, 0x12b1: 0x77e1, 0x12b2: 0x77f9, 0x12b3: 0x77f9, 0x12b4: 0x77f9, 0x12b5: 0x77f9,
+	0x12b6: 0x7811, 0x12b7: 0x7811, 0x12b8: 0x7811, 0x12b9: 0x7811, 0x12ba: 0x7829, 0x12bb: 0x7829,
+	0x12bc: 0x7829, 0x12bd: 0x7829, 0x12be: 0x7841, 0x12bf: 0x7841,
+	// Block 0x4b, offset 0x12c0
+	0x12c0: 0x7841, 0x12c1: 0x7841, 0x12c2: 0x7859, 0x12c3: 0x7859, 0x12c4: 0x7871, 0x12c5: 0x7871,
+	0x12c6: 0x7889, 0x12c7: 0x7889, 0x12c8: 0x78a1, 0x12c9: 0x78a1, 0x12ca: 0x78b9, 0x12cb: 0x78b9,
+	0x12cc: 0x78d1, 0x12cd: 0x78d1, 0x12ce: 0x78e9, 0x12cf: 0x78e9, 0x12d0: 0x78e9, 0x12d1: 0x78e9,
+	0x12d2: 0x7901, 0x12d3: 0x7901, 0x12d4: 0x7901, 0x12d5: 0x7901, 0x12d6: 0x7919, 0x12d7: 0x7919,
+	0x12d8: 0x7919, 0x12d9: 0x7919, 0x12da: 0x7931, 0x12db: 0x7931, 0x12dc: 0x7931, 0x12dd: 0x7931,
+	0x12de: 0x7949, 0x12df: 0x7949, 0x12e0: 0x7961, 0x12e1: 0x7961, 0x12e2: 0x7961, 0x12e3: 0x7961,
+	0x12e4: 0x7979, 0x12e5: 0x7979, 0x12e6: 0x7991, 0x12e7: 0x7991, 0x12e8: 0x7991, 0x12e9: 0x7991,
+	0x12ea: 0x79a9, 0x12eb: 0x79a9, 0x12ec: 0x79a9, 0x12ed: 0x79a9, 0x12ee: 0x79c1, 0x12ef: 0x79c1,
+	0x12f0: 0x79d9, 0x12f1: 0x79d9, 0x12f2: 0x0018, 0x12f3: 0x0018, 0x12f4: 0x0018, 0x12f5: 0x0018,
+	0x12f6: 0x0018, 0x12f7: 0x0018, 0x12f8: 0x0018, 0x12f9: 0x0018, 0x12fa: 0x0018, 0x12fb: 0x0018,
+	0x12fc: 0x0018, 0x12fd: 0x0018, 0x12fe: 0x0018, 0x12ff: 0x0018,
+	// Block 0x4c, offset 0x1300
+	0x1300: 0x0018, 0x1301: 0x0018, 0x1302: 0x0040, 0x1303: 0x0040, 0x1304: 0x0040, 0x1305: 0x0040,
+	0x1306: 0x0040, 0x1307: 0x0040, 0x1308: 0x0040, 0x1309: 0x0040, 0x130a: 0x0040, 0x130b: 0x0040,
+	0x130c: 0x0040, 0x130d: 0x0040, 0x130e: 0x0040, 0x130f: 0x0040, 0x1310: 0x0040, 0x1311: 0x0040,
+	0x1312: 0x0040, 0x1313: 0x79f1, 0x1314: 0x79f1, 0x1315: 0x79f1, 0x1316: 0x79f1, 0x1317: 0x7a09,
+	0x1318: 0x7a09, 0x1319: 0x7a21, 0x131a: 0x7a21, 0x131b: 0x7a39, 0x131c: 0x7a39, 0x131d: 0x0479,
+	0x131e: 0x7a51, 0x131f: 0x7a51, 0x1320: 0x7a69, 0x1321: 0x7a69, 0x1322: 0x7a81, 0x1323: 0x7a81,
+	0x1324: 0x7a99, 0x1325: 0x7a99, 0x1326: 0x7a99, 0x1327: 0x7a99, 0x1328: 0x7ab1, 0x1329: 0x7ab1,
+	0x132a: 0x7ac9, 0x132b: 0x7ac9, 0x132c: 0x7af1, 0x132d: 0x7af1, 0x132e: 0x7b19, 0x132f: 0x7b19,
+	0x1330: 0x7b41, 0x1331: 0x7b41, 0x1332: 0x7b69, 0x1333: 0x7b69, 0x1334: 0x7b91, 0x1335: 0x7b91,
+	0x1336: 0x7bb9, 0x1337: 0x7bb9, 0x1338: 0x7bb9, 0x1339: 0x7be1, 0x133a: 0x7be1, 0x133b: 0x7be1,
+	0x133c: 0x7c09, 0x133d: 0x7c09, 0x133e: 0x7c09, 0x133f: 0x7c09,
+	// Block 0x4d, offset 0x1340
+	0x1340: 0x85f9, 0x1341: 0x8621, 0x1342: 0x8649, 0x1343: 0x8671, 0x1344: 0x8699, 0x1345: 0x86c1,
+	0x1346: 0x86e9, 0x1347: 0x8711, 0x1348: 0x8739, 0x1349: 0x8761, 0x134a: 0x8789, 0x134b: 0x87b1,
+	0x134c: 0x87d9, 0x134d: 0x8801, 0x134e: 0x8829, 0x134f: 0x8851, 0x1350: 0x8879, 0x1351: 0x88a1,
+	0x1352: 0x88c9, 0x1353: 0x88f1, 0x1354: 0x8919, 0x1355: 0x8941, 0x1356: 0x8969, 0x1357: 0x8991,
+	0x1358: 0x89b9, 0x1359: 0x89e1, 0x135a: 0x8a09, 0x135b: 0x8a31, 0x135c: 0x8a59, 0x135d: 0x8a81,
+	0x135e: 0x8aaa, 0x135f: 0x8ada, 0x1360: 0x8b0a, 0x1361: 0x8b3a, 0x1362: 0x8b6a, 0x1363: 0x8b9a,
+	0x1364: 0x8bc9, 0x1365: 0x8bf1, 0x1366: 0x7c71, 0x1367: 0x8c19, 0x1368: 0x7be1, 0x1369: 0x7c99,
+	0x136a: 0x8c41, 0x136b: 0x8c69, 0x136c: 0x7d39, 0x136d: 0x8c91, 0x136e: 0x7d61, 0x136f: 0x7d89,
+	0x1370: 0x8cb9, 0x1371: 0x8ce1, 0x1372: 0x7e29, 0x1373: 0x8d09, 0x1374: 0x7e51, 0x1375: 0x7e79,
+	0x1376: 0x8d31, 0x1377: 0x8d59, 0x1378: 0x7ec9, 0x1379: 0x8d81, 0x137a: 0x7ef1, 0x137b: 0x7f19,
+	0x137c: 0x83a1, 0x137d: 0x83c9, 0x137e: 0x8441, 0x137f: 0x8469,
+	// Block 0x4e, offset 0x1380
+	0x1380: 0x8491, 0x1381: 0x8531, 0x1382: 0x8559, 0x1383: 0x8581, 0x1384: 0x85a9, 0x1385: 0x8649,
+	0x1386: 0x8671, 0x1387: 0x8699, 0x1388: 0x8da9, 0x1389: 0x8739, 0x138a: 0x8dd1, 0x138b: 0x8df9,
+	0x138c: 0x8829, 0x138d: 0x8e21, 0x138e: 0x8851, 0x138f: 0x8879, 0x1390: 0x8a81, 0x1391: 0x8e49,
+	0x1392: 0x8e71, 0x1393: 0x89b9, 0x1394: 0x8e99, 0x1395: 0x89e1, 0x1396: 0x8a09, 0x1397: 0x7c21,
+	0x1398: 0x7c49, 0x1399: 0x8ec1, 0x139a: 0x7c71, 0x139b: 0x8ee9, 0x139c: 0x7cc1, 0x139d: 0x7ce9,
+	0x139e: 0x7d11, 0x139f: 0x7d39, 0x13a0: 0x8f11, 0x13a1: 0x7db1, 0x13a2: 0x7dd9, 0x13a3: 0x7e01,
+	0x13a4: 0x7e29, 0x13a5: 0x8f39, 0x13a6: 0x7ec9, 0x13a7: 0x7f41, 0x13a8: 0x7f69, 0x13a9: 0x7f91,
+	0x13aa: 0x7fb9, 0x13ab: 0x7fe1, 0x13ac: 0x8031, 0x13ad: 0x8059, 0x13ae: 0x8081, 0x13af: 0x80a9,
+	0x13b0: 0x80d1, 0x13b1: 0x80f9, 0x13b2: 0x8f61, 0x13b3: 0x8121, 0x13b4: 0x8149, 0x13b5: 0x8171,
+	0x13b6: 0x8199, 0x13b7: 0x81c1, 0x13b8: 0x81e9, 0x13b9: 0x8239, 0x13ba: 0x8261, 0x13bb: 0x8289,
+	0x13bc: 0x82b1, 0x13bd: 0x82d9, 0x13be: 0x8301, 0x13bf: 0x8329,
+	// Block 0x4f, offset 0x13c0
+	0x13c0: 0x8351, 0x13c1: 0x8379, 0x13c2: 0x83f1, 0x13c3: 0x8419, 0x13c4: 0x84b9, 0x13c5: 0x84e1,
+	0x13c6: 0x8509, 0x13c7: 0x8531, 0x13c8: 0x8559, 0x13c9: 0x85d1, 0x13ca: 0x85f9, 0x13cb: 0x8621,
+	0x13cc: 0x8649, 0x13cd: 0x8f89, 0x13ce: 0x86c1, 0x13cf: 0x86e9, 0x13d0: 0x8711, 0x13d1: 0x8739,
+	0x13d2: 0x87b1, 0x13d3: 0x87d9, 0x13d4: 0x8801, 0x13d5: 0x8829, 0x13d6: 0x8fb1, 0x13d7: 0x88a1,
+	0x13d8: 0x88c9, 0x13d9: 0x8fd9, 0x13da: 0x8941, 0x13db: 0x8969, 0x13dc: 0x8991, 0x13dd: 0x89b9,
+	0x13de: 0x9001, 0x13df: 0x7c71, 0x13e0: 0x8ee9, 0x13e1: 0x7d39, 0x13e2: 0x8f11, 0x13e3: 0x7e29,
+	0x13e4: 0x8f39, 0x13e5: 0x7ec9, 0x13e6: 0x9029, 0x13e7: 0x80d1, 0x13e8: 0x9051, 0x13e9: 0x9079,
+	0x13ea: 0x90a1, 0x13eb: 0x8531, 0x13ec: 0x8559, 0x13ed: 0x8649, 0x13ee: 0x8829, 0x13ef: 0x8fb1,
+	0x13f0: 0x89b9, 0x13f1: 0x9001, 0x13f2: 0x90c9, 0x13f3: 0x9101, 0x13f4: 0x9139, 0x13f5: 0x9171,
+	0x13f6: 0x9199, 0x13f7: 0x91c1, 0x13f8: 0x91e9, 0x13f9: 0x9211, 0x13fa: 0x9239, 0x13fb: 0x9261,
+	0x13fc: 0x9289, 0x13fd: 0x92b1, 0x13fe: 0x92d9, 0x13ff: 0x9301,
+	// Block 0x50, offset 0x1400
+	0x1400: 0x9329, 0x1401: 0x9351, 0x1402: 0x9379, 0x1403: 0x93a1, 0x1404: 0x93c9, 0x1405: 0x93f1,
+	0x1406: 0x9419, 0x1407: 0x9441, 0x1408: 0x9469, 0x1409: 0x9491, 0x140a: 0x94b9, 0x140b: 0x94e1,
+	0x140c: 0x9079, 0x140d: 0x9509, 0x140e: 0x9531, 0x140f: 0x9559, 0x1410: 0x9581, 0x1411: 0x9171,
+	0x1412: 0x9199, 0x1413: 0x91c1, 0x1414: 0x91e9, 0x1415: 0x9211, 0x1416: 0x9239, 0x1417: 0x9261,
+	0x1418: 0x9289, 0x1419: 0x92b1, 0x141a: 0x92d9, 0x141b: 0x9301, 0x141c: 0x9329, 0x141d: 0x9351,
+	0x141e: 0x9379, 0x141f: 0x93a1, 0x1420: 0x93c9, 0x1421: 0x93f1, 0x1422: 0x9419, 0x1423: 0x9441,
+	0x1424: 0x9469, 0x1425: 0x9491, 0x1426: 0x94b9, 0x1427: 0x94e1, 0x1428: 0x9079, 0x1429: 0x9509,
+	0x142a: 0x9531, 0x142b: 0x9559, 0x142c: 0x9581, 0x142d: 0x9491, 0x142e: 0x94b9, 0x142f: 0x94e1,
+	0x1430: 0x9079, 0x1431: 0x9051, 0x1432: 0x90a1, 0x1433: 0x8211, 0x1434: 0x8059, 0x1435: 0x8081,
+	0x1436: 0x80a9, 0x1437: 0x9491, 0x1438: 0x94b9, 0x1439: 0x94e1, 0x143a: 0x8211, 0x143b: 0x8239,
+	0x143c: 0x95a9, 0x143d: 0x95a9, 0x143e: 0x0018, 0x143f: 0x0018,
+	// Block 0x51, offset 0x1440
+	0x1440: 0x0040, 0x1441: 0x0040, 0x1442: 0x0040, 0x1443: 0x0040, 0x1444: 0x0040, 0x1445: 0x0040,
+	0x1446: 0x0040, 0x1447: 0x0040, 0x1448: 0x0040, 0x1449: 0x0040, 0x144a: 0x0040, 0x144b: 0x0040,
+	0x144c: 0x0040, 0x144d: 0x0040, 0x144e: 0x0040, 0x144f: 0x0040, 0x1450: 0x95d1, 0x1451: 0x9609,
+	0x1452: 0x9609, 0x1453: 0x9641, 0x1454: 0x9679, 0x1455: 0x96b1, 0x1456: 0x96e9, 0x1457: 0x9721,
+	0x1458: 0x9759, 0x1459: 0x9759, 0x145a: 0x9791, 0x145b: 0x97c9, 0x145c: 0x9801, 0x145d: 0x9839,
+	0x145e: 0x9871, 0x145f: 0x98a9, 0x1460: 0x98a9, 0x1461: 0x98e1, 0x1462: 0x9919, 0x1463: 0x9919,
+	0x1464: 0x9951, 0x1465: 0x9951, 0x1466: 0x9989, 0x1467: 0x99c1, 0x1468: 0x99c1, 0x1469: 0x99f9,
+	0x146a: 0x9a31, 0x146b: 0x9a31, 0x146c: 0x9a69, 0x146d: 0x9a69, 0x146e: 0x9aa1, 0x146f: 0x9ad9,
+	0x1470: 0x9ad9, 0x1471: 0x9b11, 0x1472: 0x9b11, 0x1473: 0x9b49, 0x1474: 0x9b81, 0x1475: 0x9bb9,
+	0x1476: 0x9bf1, 0x1477: 0x9bf1, 0x1478: 0x9c29, 0x1479: 0x9c61, 0x147a: 0x9c99, 0x147b: 0x9cd1,
+	0x147c: 0x9d09, 0x147d: 0x9d09, 0x147e: 0x9d41, 0x147f: 0x9d79,
+	// Block 0x52, offset 0x1480
+	0x1480: 0xa949, 0x1481: 0xa981, 0x1482: 0xa9b9, 0x1483: 0xa8a1, 0x1484: 0x9bb9, 0x1485: 0x9989,
+	0x1486: 0xa9f1, 0x1487: 0xaa29, 0x1488: 0x0040, 0x1489: 0x0040, 0x148a: 0x0040, 0x148b: 0x0040,
+	0x148c: 0x0040, 0x148d: 0x0040, 0x148e: 0x0040, 0x148f: 0x0040, 0x1490: 0x0040, 0x1491: 0x0040,
+	0x1492: 0x0040, 0x1493: 0x0040, 0x1494: 0x0040, 0x1495: 0x0040, 0x1496: 0x0040, 0x1497: 0x0040,
+	0x1498: 0x0040, 0x1499: 0x0040, 0x149a: 0x0040, 0x149b: 0x0040, 0x149c: 0x0040, 0x149d: 0x0040,
+	0x149e: 0x0040, 0x149f: 0x0040, 0x14a0: 0x0040, 0x14a1: 0x0040, 0x14a2: 0x0040, 0x14a3: 0x0040,
+	0x14a4: 0x0040, 0x14a5: 0x0040, 0x14a6: 0x0040, 0x14a7: 0x0040, 0x14a8: 0x0040, 0x14a9: 0x0040,
+	0x14aa: 0x0040, 0x14ab: 0x0040, 0x14ac: 0x0040, 0x14ad: 0x0040, 0x14ae: 0x0040, 0x14af: 0x0040,
+	0x14b0: 0xaa61, 0x14b1: 0xaa99, 0x14b2: 0xaad1, 0x14b3: 0xab19, 0x14b4: 0xab61, 0x14b5: 0xaba9,
+	0x14b6: 0xabf1, 0x14b7: 0xac39, 0x14b8: 0xac81, 0x14b9: 0xacc9, 0x14ba: 0xad02, 0x14bb: 0xae12,
+	0x14bc: 0xae91, 0x14bd: 0x0018, 0x14be: 0x0040, 0x14bf: 0x0040,
+	// Block 0x53, offset 0x14c0
+	0x14c0: 0x13c0, 0x14c1: 0x13c0, 0x14c2: 0x13c0, 0x14c3: 0x13c0, 0x14c4: 0x13c0, 0x14c5: 0x13c0,
+	0x14c6: 0x13c0, 0x14c7: 0x13c0, 0x14c8: 0x13c0, 0x14c9: 0x13c0, 0x14ca: 0x13c0, 0x14cb: 0x13c0,
+	0x14cc: 0x13c0, 0x14cd: 0x13c0, 0x14ce: 0x13c0, 0x14cf: 0x13c0, 0x14d0: 0xaeda, 0x14d1: 0x7d55,
+	0x14d2: 0x0040, 0x14d3: 0xaeea, 0x14d4: 0x03c2, 0x14d5: 0xaefa, 0x14d6: 0xaf0a, 0x14d7: 0x7d75,
+	0x14d8: 0x7d95, 0x14d9: 0x0040, 0x14da: 0x0040, 0x14db: 0x0040, 0x14dc: 0x0040, 0x14dd: 0x0040,
+	0x14de: 0x0040, 0x14df: 0x0040, 0x14e0: 0x1308, 0x14e1: 0x1308, 0x14e2: 0x1308, 0x14e3: 0x1308,
+	0x14e4: 0x1308, 0x14e5: 0x1308, 0x14e6: 0x1308, 0x14e7: 0x1308, 0x14e8: 0x1308, 0x14e9: 0x1308,
+	0x14ea: 0x1308, 0x14eb: 0x1308, 0x14ec: 0x1308, 0x14ed: 0x1308, 0x14ee: 0x1308, 0x14ef: 0x1308,
+	0x14f0: 0x0040, 0x14f1: 0x7db5, 0x14f2: 0x7dd5, 0x14f3: 0xaf1a, 0x14f4: 0xaf1a, 0x14f5: 0x1fd2,
+	0x14f6: 0x1fe2, 0x14f7: 0xaf2a, 0x14f8: 0xaf3a, 0x14f9: 0x7df5, 0x14fa: 0x7e15, 0x14fb: 0x7e35,
+	0x14fc: 0x7df5, 0x14fd: 0x7e55, 0x14fe: 0x7e75, 0x14ff: 0x7e55,
+	// Block 0x54, offset 0x1500
+	0x1500: 0x7e95, 0x1501: 0x7eb5, 0x1502: 0x7ed5, 0x1503: 0x7eb5, 0x1504: 0x7ef5, 0x1505: 0x0018,
+	0x1506: 0x0018, 0x1507: 0xaf4a, 0x1508: 0xaf5a, 0x1509: 0x7f16, 0x150a: 0x7f36, 0x150b: 0x7f56,
+	0x150c: 0x7f76, 0x150d: 0xaf1a, 0x150e: 0xaf1a, 0x150f: 0xaf1a, 0x1510: 0xaeda, 0x1511: 0x7f95,
+	0x1512: 0x0040, 0x1513: 0x0040, 0x1514: 0x03c2, 0x1515: 0xaeea, 0x1516: 0xaf0a, 0x1517: 0xaefa,
+	0x1518: 0x7fb5, 0x1519: 0x1fd2, 0x151a: 0x1fe2, 0x151b: 0xaf2a, 0x151c: 0xaf3a, 0x151d: 0x7e95,
+	0x151e: 0x7ef5, 0x151f: 0xaf6a, 0x1520: 0xaf7a, 0x1521: 0xaf8a, 0x1522: 0x1fb2, 0x1523: 0xaf99,
+	0x1524: 0xafaa, 0x1525: 0xafba, 0x1526: 0x1fc2, 0x1527: 0x0040, 0x1528: 0xafca, 0x1529: 0xafda,
+	0x152a: 0xafea, 0x152b: 0xaffa, 0x152c: 0x0040, 0x152d: 0x0040, 0x152e: 0x0040, 0x152f: 0x0040,
+	0x1530: 0x7fd6, 0x1531: 0xb009, 0x1532: 0x7ff6, 0x1533: 0x0008, 0x1534: 0x8016, 0x1535: 0x0040,
+	0x1536: 0x8036, 0x1537: 0xb031, 0x1538: 0x8056, 0x1539: 0xb059, 0x153a: 0x8076, 0x153b: 0xb081,
+	0x153c: 0x8096, 0x153d: 0xb0a9, 0x153e: 0x80b6, 0x153f: 0xb0d1,
+	// Block 0x55, offset 0x1540
+	0x1540: 0xb0f9, 0x1541: 0xb111, 0x1542: 0xb111, 0x1543: 0xb129, 0x1544: 0xb129, 0x1545: 0xb141,
+	0x1546: 0xb141, 0x1547: 0xb159, 0x1548: 0xb159, 0x1549: 0xb171, 0x154a: 0xb171, 0x154b: 0xb171,
+	0x154c: 0xb171, 0x154d: 0xb189, 0x154e: 0xb189, 0x154f: 0xb1a1, 0x1550: 0xb1a1, 0x1551: 0xb1a1,
+	0x1552: 0xb1a1, 0x1553: 0xb1b9, 0x1554: 0xb1b9, 0x1555: 0xb1d1, 0x1556: 0xb1d1, 0x1557: 0xb1d1,
+	0x1558: 0xb1d1, 0x1559: 0xb1e9, 0x155a: 0xb1e9, 0x155b: 0xb1e9, 0x155c: 0xb1e9, 0x155d: 0xb201,
+	0x155e: 0xb201, 0x155f: 0xb201, 0x1560: 0xb201, 0x1561: 0xb219, 0x1562: 0xb219, 0x1563: 0xb219,
+	0x1564: 0xb219, 0x1565: 0xb231, 0x1566: 0xb231, 0x1567: 0xb231, 0x1568: 0xb231, 0x1569: 0xb249,
+	0x156a: 0xb249, 0x156b: 0xb261, 0x156c: 0xb261, 0x156d: 0xb279, 0x156e: 0xb279, 0x156f: 0xb291,
+	0x1570: 0xb291, 0x1571: 0xb2a9, 0x1572: 0xb2a9, 0x1573: 0xb2a9, 0x1574: 0xb2a9, 0x1575: 0xb2c1,
+	0x1576: 0xb2c1, 0x1577: 0xb2c1, 0x1578: 0xb2c1, 0x1579: 0xb2d9, 0x157a: 0xb2d9, 0x157b: 0xb2d9,
+	0x157c: 0xb2d9, 0x157d: 0xb2f1, 0x157e: 0xb2f1, 0x157f: 0xb2f1,
+	// Block 0x56, offset 0x1580
+	0x1580: 0xb2f1, 0x1581: 0xb309, 0x1582: 0xb309, 0x1583: 0xb309, 0x1584: 0xb309, 0x1585: 0xb321,
+	0x1586: 0xb321, 0x1587: 0xb321, 0x1588: 0xb321, 0x1589: 0xb339, 0x158a: 0xb339, 0x158b: 0xb339,
+	0x158c: 0xb339, 0x158d: 0xb351, 0x158e: 0xb351, 0x158f: 0xb351, 0x1590: 0xb351, 0x1591: 0xb369,
+	0x1592: 0xb369, 0x1593: 0xb369, 0x1594: 0xb369, 0x1595: 0xb381, 0x1596: 0xb381, 0x1597: 0xb381,
+	0x1598: 0xb381, 0x1599: 0xb399, 0x159a: 0xb399, 0x159b: 0xb399, 0x159c: 0xb399, 0x159d: 0xb3b1,
+	0x159e: 0xb3b1, 0x159f: 0xb3b1, 0x15a0: 0xb3b1, 0x15a1: 0xb3c9, 0x15a2: 0xb3c9, 0x15a3: 0xb3c9,
+	0x15a4: 0xb3c9, 0x15a5: 0xb3e1, 0x15a6: 0xb3e1, 0x15a7: 0xb3e1, 0x15a8: 0xb3e1, 0x15a9: 0xb3f9,
+	0x15aa: 0xb3f9, 0x15ab: 0xb3f9, 0x15ac: 0xb3f9, 0x15ad: 0xb411, 0x15ae: 0xb411, 0x15af: 0x7ab1,
+	0x15b0: 0x7ab1, 0x15b1: 0xb429, 0x15b2: 0xb429, 0x15b3: 0xb429, 0x15b4: 0xb429, 0x15b5: 0xb441,
+	0x15b6: 0xb441, 0x15b7: 0xb469, 0x15b8: 0xb469, 0x15b9: 0xb491, 0x15ba: 0xb491, 0x15bb: 0xb4b9,
+	0x15bc: 0xb4b9, 0x15bd: 0x0040, 0x15be: 0x0040, 0x15bf: 0x03c0,
+	// Block 0x57, offset 0x15c0
+	0x15c0: 0x0040, 0x15c1: 0xaefa, 0x15c2: 0xb4e2, 0x15c3: 0xaf6a, 0x15c4: 0xafda, 0x15c5: 0xafea,
+	0x15c6: 0xaf7a, 0x15c7: 0xb4f2, 0x15c8: 0x1fd2, 0x15c9: 0x1fe2, 0x15ca: 0xaf8a, 0x15cb: 0x1fb2,
+	0x15cc: 0xaeda, 0x15cd: 0xaf99, 0x15ce: 0x29d1, 0x15cf: 0xb502, 0x15d0: 0x1f41, 0x15d1: 0x00c9,
+	0x15d2: 0x0069, 0x15d3: 0x0079, 0x15d4: 0x1f51, 0x15d5: 0x1f61, 0x15d6: 0x1f71, 0x15d7: 0x1f81,
+	0x15d8: 0x1f91, 0x15d9: 0x1fa1, 0x15da: 0xaeea, 0x15db: 0x03c2, 0x15dc: 0xafaa, 0x15dd: 0x1fc2,
+	0x15de: 0xafba, 0x15df: 0xaf0a, 0x15e0: 0xaffa, 0x15e1: 0x0039, 0x15e2: 0x0ee9, 0x15e3: 0x1159,
+	0x15e4: 0x0ef9, 0x15e5: 0x0f09, 0x15e6: 0x1199, 0x15e7: 0x0f31, 0x15e8: 0x0249, 0x15e9: 0x0f41,
+	0x15ea: 0x0259, 0x15eb: 0x0f51, 0x15ec: 0x0359, 0x15ed: 0x0f61, 0x15ee: 0x0f71, 0x15ef: 0x00d9,
+	0x15f0: 0x0f99, 0x15f1: 0x2039, 0x15f2: 0x0269, 0x15f3: 0x01d9, 0x15f4: 0x0fa9, 0x15f5: 0x0fb9,
+	0x15f6: 0x1089, 0x15f7: 0x0279, 0x15f8: 0x0369, 0x15f9: 0x0289, 0x15fa: 0x13d1, 0x15fb: 0xaf4a,
+	0x15fc: 0xafca, 0x15fd: 0xaf5a, 0x15fe: 0xb512, 0x15ff: 0xaf1a,
+	// Block 0x58, offset 0x1600
+	0x1600: 0x1caa, 0x1601: 0x0039, 0x1602: 0x0ee9, 0x1603: 0x1159, 0x1604: 0x0ef9, 0x1605: 0x0f09,
+	0x1606: 0x1199, 0x1607: 0x0f31, 0x1608: 0x0249, 0x1609: 0x0f41, 0x160a: 0x0259, 0x160b: 0x0f51,
+	0x160c: 0x0359, 0x160d: 0x0f61, 0x160e: 0x0f71, 0x160f: 0x00d9, 0x1610: 0x0f99, 0x1611: 0x2039,
+	0x1612: 0x0269, 0x1613: 0x01d9, 0x1614: 0x0fa9, 0x1615: 0x0fb9, 0x1616: 0x1089, 0x1617: 0x0279,
+	0x1618: 0x0369, 0x1619: 0x0289, 0x161a: 0x13d1, 0x161b: 0xaf2a, 0x161c: 0xb522, 0x161d: 0xaf3a,
+	0x161e: 0xb532, 0x161f: 0x80d5, 0x1620: 0x80f5, 0x1621: 0x29d1, 0x1622: 0x8115, 0x1623: 0x8115,
+	0x1624: 0x8135, 0x1625: 0x8155, 0x1626: 0x8175, 0x1627: 0x8195, 0x1628: 0x81b5, 0x1629: 0x81d5,
+	0x162a: 0x81f5, 0x162b: 0x8215, 0x162c: 0x8235, 0x162d: 0x8255, 0x162e: 0x8275, 0x162f: 0x8295,
+	0x1630: 0x82b5, 0x1631: 0x82d5, 0x1632: 0x82f5, 0x1633: 0x8315, 0x1634: 0x8335, 0x1635: 0x8355,
+	0x1636: 0x8375, 0x1637: 0x8395, 0x1638: 0x83b5, 0x1639: 0x83d5, 0x163a: 0x83f5, 0x163b: 0x8415,
+	0x163c: 0x81b5, 0x163d: 0x8435, 0x163e: 0x8455, 0x163f: 0x8215,
+	// Block 0x59, offset 0x1640
+	0x1640: 0x8475, 0x1641: 0x8495, 0x1642: 0x84b5, 0x1643: 0x84d5, 0x1644: 0x84f5, 0x1645: 0x8515,
+	0x1646: 0x8535, 0x1647: 0x8555, 0x1648: 0x84d5, 0x1649: 0x8575, 0x164a: 0x84d5, 0x164b: 0x8595,
+	0x164c: 0x8595, 0x164d: 0x85b5, 0x164e: 0x85b5, 0x164f: 0x85d5, 0x1650: 0x8515, 0x1651: 0x85f5,
+	0x1652: 0x8615, 0x1653: 0x85f5, 0x1654: 0x8635, 0x1655: 0x8615, 0x1656: 0x8655, 0x1657: 0x8655,
+	0x1658: 0x8675, 0x1659: 0x8675, 0x165a: 0x8695, 0x165b: 0x8695, 0x165c: 0x8615, 0x165d: 0x8115,
+	0x165e: 0x86b5, 0x165f: 0x86d5, 0x1660: 0x0040, 0x1661: 0x86f5, 0x1662: 0x8715, 0x1663: 0x8735,
+	0x1664: 0x8755, 0x1665: 0x8735, 0x1666: 0x8775, 0x1667: 0x8795, 0x1668: 0x87b5, 0x1669: 0x87b5,
+	0x166a: 0x87d5, 0x166b: 0x87d5, 0x166c: 0x87f5, 0x166d: 0x87f5, 0x166e: 0x87d5, 0x166f: 0x87d5,
+	0x1670: 0x8815, 0x1671: 0x8835, 0x1672: 0x8855, 0x1673: 0x8875, 0x1674: 0x8895, 0x1675: 0x88b5,
+	0x1676: 0x88b5, 0x1677: 0x88b5, 0x1678: 0x88d5, 0x1679: 0x88d5, 0x167a: 0x88d5, 0x167b: 0x88d5,
+	0x167c: 0x87b5, 0x167d: 0x87b5, 0x167e: 0x87b5, 0x167f: 0x0040,
+	// Block 0x5a, offset 0x1680
+	0x1680: 0x0040, 0x1681: 0x0040, 0x1682: 0x8715, 0x1683: 0x86f5, 0x1684: 0x88f5, 0x1685: 0x86f5,
+	0x1686: 0x8715, 0x1687: 0x86f5, 0x1688: 0x0040, 0x1689: 0x0040, 0x168a: 0x8915, 0x168b: 0x8715,
+	0x168c: 0x8935, 0x168d: 0x88f5, 0x168e: 0x8935, 0x168f: 0x8715, 0x1690: 0x0040, 0x1691: 0x0040,
+	0x1692: 0x8955, 0x1693: 0x8975, 0x1694: 0x8875, 0x1695: 0x8935, 0x1696: 0x88f5, 0x1697: 0x8935,
+	0x1698: 0x0040, 0x1699: 0x0040, 0x169a: 0x8995, 0x169b: 0x89b5, 0x169c: 0x8995, 0x169d: 0x0040,
+	0x169e: 0x0040, 0x169f: 0x0040, 0x16a0: 0xb541, 0x16a1: 0xb559, 0x16a2: 0xb571, 0x16a3: 0x89d6,
+	0x16a4: 0xb589, 0x16a5: 0xb5a1, 0x16a6: 0x89f5, 0x16a7: 0x0040, 0x16a8: 0x8a15, 0x16a9: 0x8a35,
+	0x16aa: 0x8a55, 0x16ab: 0x8a35, 0x16ac: 0x8a75, 0x16ad: 0x8a95, 0x16ae: 0x8ab5, 0x16af: 0x0040,
+	0x16b0: 0x0040, 0x16b1: 0x0040, 0x16b2: 0x0040, 0x16b3: 0x0040, 0x16b4: 0x0040, 0x16b5: 0x0040,
+	0x16b6: 0x0040, 0x16b7: 0x0040, 0x16b8: 0x0040, 0x16b9: 0x0340, 0x16ba: 0x0340, 0x16bb: 0x0340,
+	0x16bc: 0x0040, 0x16bd: 0x0040, 0x16be: 0x0040, 0x16bf: 0x0040,
+	// Block 0x5b, offset 0x16c0
+	0x16c0: 0x0208, 0x16c1: 0x0208, 0x16c2: 0x0208, 0x16c3: 0x0208, 0x16c4: 0x0208, 0x16c5: 0x0408,
+	0x16c6: 0x0008, 0x16c7: 0x0408, 0x16c8: 0x0018, 0x16c9: 0x0408, 0x16ca: 0x0408, 0x16cb: 0x0008,
+	0x16cc: 0x0008, 0x16cd: 0x0108, 0x16ce: 0x0408, 0x16cf: 0x0408, 0x16d0: 0x0408, 0x16d1: 0x0408,
+	0x16d2: 0x0408, 0x16d3: 0x0208, 0x16d4: 0x0208, 0x16d5: 0x0208, 0x16d6: 0x0208, 0x16d7: 0x0108,
+	0x16d8: 0x0208, 0x16d9: 0x0208, 0x16da: 0x0208, 0x16db: 0x0208, 0x16dc: 0x0208, 0x16dd: 0x0408,
+	0x16de: 0x0208, 0x16df: 0x0208, 0x16e0: 0x0208, 0x16e1: 0x0408, 0x16e2: 0x0008, 0x16e3: 0x0008,
+	0x16e4: 0x0408, 0x16e5: 0x1308, 0x16e6: 0x1308, 0x16e7: 0x0040, 0x16e8: 0x0040, 0x16e9: 0x0040,
+	0x16ea: 0x0040, 0x16eb: 0x0218, 0x16ec: 0x0218, 0x16ed: 0x0218, 0x16ee: 0x0218, 0x16ef: 0x0418,
+	0x16f0: 0x0018, 0x16f1: 0x0018, 0x16f2: 0x0018, 0x16f3: 0x0018, 0x16f4: 0x0018, 0x16f5: 0x0018,
+	0x16f6: 0x0018, 0x16f7: 0x0040, 0x16f8: 0x0040, 0x16f9: 0x0040, 0x16fa: 0x0040, 0x16fb: 0x0040,
+	0x16fc: 0x0040, 0x16fd: 0x0040, 0x16fe: 0x0040, 0x16ff: 0x0040,
+	// Block 0x5c, offset 0x1700
+	0x1700: 0x0208, 0x1701: 0x0408, 0x1702: 0x0208, 0x1703: 0x0408, 0x1704: 0x0408, 0x1705: 0x0408,
+	0x1706: 0x0208, 0x1707: 0x0208, 0x1708: 0x0208, 0x1709: 0x0408, 0x170a: 0x0208, 0x170b: 0x0208,
+	0x170c: 0x0408, 0x170d: 0x0208, 0x170e: 0x0408, 0x170f: 0x0408, 0x1710: 0x0208, 0x1711: 0x0408,
+	0x1712: 0x0040, 0x1713: 0x0040, 0x1714: 0x0040, 0x1715: 0x0040, 0x1716: 0x0040, 0x1717: 0x0040,
+	0x1718: 0x0040, 0x1719: 0x0018, 0x171a: 0x0018, 0x171b: 0x0018, 0x171c: 0x0018, 0x171d: 0x0040,
+	0x171e: 0x0040, 0x171f: 0x0040, 0x1720: 0x0040, 0x1721: 0x0040, 0x1722: 0x0040, 0x1723: 0x0040,
+	0x1724: 0x0040, 0x1725: 0x0040, 0x1726: 0x0040, 0x1727: 0x0040, 0x1728: 0x0040, 0x1729: 0x0418,
+	0x172a: 0x0418, 0x172b: 0x0418, 0x172c: 0x0418, 0x172d: 0x0218, 0x172e: 0x0218, 0x172f: 0x0018,
+	0x1730: 0x0040, 0x1731: 0x0040, 0x1732: 0x0040, 0x1733: 0x0040, 0x1734: 0x0040, 0x1735: 0x0040,
+	0x1736: 0x0040, 0x1737: 0x0040, 0x1738: 0x0040, 0x1739: 0x0040, 0x173a: 0x0040, 0x173b: 0x0040,
+	0x173c: 0x0040, 0x173d: 0x0040, 0x173e: 0x0040, 0x173f: 0x0040,
+	// Block 0x5d, offset 0x1740
+	0x1740: 0x1308, 0x1741: 0x1308, 0x1742: 0x1008, 0x1743: 0x1008, 0x1744: 0x0040, 0x1745: 0x0008,
+	0x1746: 0x0008, 0x1747: 0x0008, 0x1748: 0x0008, 0x1749: 0x0008, 0x174a: 0x0008, 0x174b: 0x0008,
+	0x174c: 0x0008, 0x174d: 0x0040, 0x174e: 0x0040, 0x174f: 0x0008, 0x1750: 0x0008, 0x1751: 0x0040,
+	0x1752: 0x0040, 0x1753: 0x0008, 0x1754: 0x0008, 0x1755: 0x0008, 0x1756: 0x0008, 0x1757: 0x0008,
+	0x1758: 0x0008, 0x1759: 0x0008, 0x175a: 0x0008, 0x175b: 0x0008, 0x175c: 0x0008, 0x175d: 0x0008,
+	0x175e: 0x0008, 0x175f: 0x0008, 0x1760: 0x0008, 0x1761: 0x0008, 0x1762: 0x0008, 0x1763: 0x0008,
+	0x1764: 0x0008, 0x1765: 0x0008, 0x1766: 0x0008, 0x1767: 0x0008, 0x1768: 0x0008, 0x1769: 0x0040,
+	0x176a: 0x0008, 0x176b: 0x0008, 0x176c: 0x0008, 0x176d: 0x0008, 0x176e: 0x0008, 0x176f: 0x0008,
+	0x1770: 0x0008, 0x1771: 0x0040, 0x1772: 0x0008, 0x1773: 0x0008, 0x1774: 0x0040, 0x1775: 0x0008,
+	0x1776: 0x0008, 0x1777: 0x0008, 0x1778: 0x0008, 0x1779: 0x0008, 0x177a: 0x0040, 0x177b: 0x0040,
+	0x177c: 0x1308, 0x177d: 0x0008, 0x177e: 0x1008, 0x177f: 0x1008,
+	// Block 0x5e, offset 0x1780
+	0x1780: 0x1308, 0x1781: 0x1008, 0x1782: 0x1008, 0x1783: 0x1008, 0x1784: 0x1008, 0x1785: 0x0040,
+	0x1786: 0x0040, 0x1787: 0x1008, 0x1788: 0x1008, 0x1789: 0x0040, 0x178a: 0x0040, 0x178b: 0x1008,
+	0x178c: 0x1008, 0x178d: 0x1808, 0x178e: 0x0040, 0x178f: 0x0040, 0x1790: 0x0008, 0x1791: 0x0040,
+	0x1792: 0x0040, 0x1793: 0x0040, 0x1794: 0x0040, 0x1795: 0x0040, 0x1796: 0x0040, 0x1797: 0x1008,
+	0x1798: 0x0040, 0x1799: 0x0040, 0x179a: 0x0040, 0x179b: 0x0040, 0x179c: 0x0040, 0x179d: 0x0008,
+	0x179e: 0x0008, 0x179f: 0x0008, 0x17a0: 0x0008, 0x17a1: 0x0008, 0x17a2: 0x1008, 0x17a3: 0x1008,
+	0x17a4: 0x0040, 0x17a5: 0x0040, 0x17a6: 0x1308, 0x17a7: 0x1308, 0x17a8: 0x1308, 0x17a9: 0x1308,
+	0x17aa: 0x1308, 0x17ab: 0x1308, 0x17ac: 0x1308, 0x17ad: 0x0040, 0x17ae: 0x0040, 0x17af: 0x0040,
+	0x17b0: 0x1308, 0x17b1: 0x1308, 0x17b2: 0x1308, 0x17b3: 0x1308, 0x17b4: 0x1308, 0x17b5: 0x0040,
+	0x17b6: 0x0040, 0x17b7: 0x0040, 0x17b8: 0x0040, 0x17b9: 0x0040, 0x17ba: 0x0040, 0x17bb: 0x0040,
+	0x17bc: 0x0040, 0x17bd: 0x0040, 0x17be: 0x0040, 0x17bf: 0x0040,
+	// Block 0x5f, offset 0x17c0
+	0x17c0: 0x0039, 0x17c1: 0x0ee9, 0x17c2: 0x1159, 0x17c3: 0x0ef9, 0x17c4: 0x0f09, 0x17c5: 0x1199,
+	0x17c6: 0x0f31, 0x17c7: 0x0249, 0x17c8: 0x0f41, 0x17c9: 0x0259, 0x17ca: 0x0f51, 0x17cb: 0x0359,
+	0x17cc: 0x0f61, 0x17cd: 0x0f71, 0x17ce: 0x00d9, 0x17cf: 0x0f99, 0x17d0: 0x2039, 0x17d1: 0x0269,
+	0x17d2: 0x01d9, 0x17d3: 0x0fa9, 0x17d4: 0x0fb9, 0x17d5: 0x1089, 0x17d6: 0x0279, 0x17d7: 0x0369,
+	0x17d8: 0x0289, 0x17d9: 0x13d1, 0x17da: 0x0039, 0x17db: 0x0ee9, 0x17dc: 0x1159, 0x17dd: 0x0ef9,
+	0x17de: 0x0f09, 0x17df: 0x1199, 0x17e0: 0x0f31, 0x17e1: 0x0249, 0x17e2: 0x0f41, 0x17e3: 0x0259,
+	0x17e4: 0x0f51, 0x17e5: 0x0359, 0x17e6: 0x0f61, 0x17e7: 0x0f71, 0x17e8: 0x00d9, 0x17e9: 0x0f99,
+	0x17ea: 0x2039, 0x17eb: 0x0269, 0x17ec: 0x01d9, 0x17ed: 0x0fa9, 0x17ee: 0x0fb9, 0x17ef: 0x1089,
+	0x17f0: 0x0279, 0x17f1: 0x0369, 0x17f2: 0x0289, 0x17f3: 0x13d1, 0x17f4: 0x0039, 0x17f5: 0x0ee9,
+	0x17f6: 0x1159, 0x17f7: 0x0ef9, 0x17f8: 0x0f09, 0x17f9: 0x1199, 0x17fa: 0x0f31, 0x17fb: 0x0249,
+	0x17fc: 0x0f41, 0x17fd: 0x0259, 0x17fe: 0x0f51, 0x17ff: 0x0359,
+	// Block 0x60, offset 0x1800
+	0x1800: 0x0f61, 0x1801: 0x0f71, 0x1802: 0x00d9, 0x1803: 0x0f99, 0x1804: 0x2039, 0x1805: 0x0269,
+	0x1806: 0x01d9, 0x1807: 0x0fa9, 0x1808: 0x0fb9, 0x1809: 0x1089, 0x180a: 0x0279, 0x180b: 0x0369,
+	0x180c: 0x0289, 0x180d: 0x13d1, 0x180e: 0x0039, 0x180f: 0x0ee9, 0x1810: 0x1159, 0x1811: 0x0ef9,
+	0x1812: 0x0f09, 0x1813: 0x1199, 0x1814: 0x0f31, 0x1815: 0x0040, 0x1816: 0x0f41, 0x1817: 0x0259,
+	0x1818: 0x0f51, 0x1819: 0x0359, 0x181a: 0x0f61, 0x181b: 0x0f71, 0x181c: 0x00d9, 0x181d: 0x0f99,
+	0x181e: 0x2039, 0x181f: 0x0269, 0x1820: 0x01d9, 0x1821: 0x0fa9, 0x1822: 0x0fb9, 0x1823: 0x1089,
+	0x1824: 0x0279, 0x1825: 0x0369, 0x1826: 0x0289, 0x1827: 0x13d1, 0x1828: 0x0039, 0x1829: 0x0ee9,
+	0x182a: 0x1159, 0x182b: 0x0ef9, 0x182c: 0x0f09, 0x182d: 0x1199, 0x182e: 0x0f31, 0x182f: 0x0249,
+	0x1830: 0x0f41, 0x1831: 0x0259, 0x1832: 0x0f51, 0x1833: 0x0359, 0x1834: 0x0f61, 0x1835: 0x0f71,
+	0x1836: 0x00d9, 0x1837: 0x0f99, 0x1838: 0x2039, 0x1839: 0x0269, 0x183a: 0x01d9, 0x183b: 0x0fa9,
+	0x183c: 0x0fb9, 0x183d: 0x1089, 0x183e: 0x0279, 0x183f: 0x0369,
+	// Block 0x61, offset 0x1840
+	0x1840: 0x0289, 0x1841: 0x13d1, 0x1842: 0x0039, 0x1843: 0x0ee9, 0x1844: 0x1159, 0x1845: 0x0ef9,
+	0x1846: 0x0f09, 0x1847: 0x1199, 0x1848: 0x0f31, 0x1849: 0x0249, 0x184a: 0x0f41, 0x184b: 0x0259,
+	0x184c: 0x0f51, 0x184d: 0x0359, 0x184e: 0x0f61, 0x184f: 0x0f71, 0x1850: 0x00d9, 0x1851: 0x0f99,
+	0x1852: 0x2039, 0x1853: 0x0269, 0x1854: 0x01d9, 0x1855: 0x0fa9, 0x1856: 0x0fb9, 0x1857: 0x1089,
+	0x1858: 0x0279, 0x1859: 0x0369, 0x185a: 0x0289, 0x185b: 0x13d1, 0x185c: 0x0039, 0x185d: 0x0040,
+	0x185e: 0x1159, 0x185f: 0x0ef9, 0x1860: 0x0040, 0x1861: 0x0040, 0x1862: 0x0f31, 0x1863: 0x0040,
+	0x1864: 0x0040, 0x1865: 0x0259, 0x1866: 0x0f51, 0x1867: 0x0040, 0x1868: 0x0040, 0x1869: 0x0f71,
+	0x186a: 0x00d9, 0x186b: 0x0f99, 0x186c: 0x2039, 0x186d: 0x0040, 0x186e: 0x01d9, 0x186f: 0x0fa9,
+	0x1870: 0x0fb9, 0x1871: 0x1089, 0x1872: 0x0279, 0x1873: 0x0369, 0x1874: 0x0289, 0x1875: 0x13d1,
+	0x1876: 0x0039, 0x1877: 0x0ee9, 0x1878: 0x1159, 0x1879: 0x0ef9, 0x187a: 0x0040, 0x187b: 0x1199,
+	0x187c: 0x0040, 0x187d: 0x0249, 0x187e: 0x0f41, 0x187f: 0x0259,
+	// Block 0x62, offset 0x1880
+	0x1880: 0x0f51, 0x1881: 0x0359, 0x1882: 0x0f61, 0x1883: 0x0f71, 0x1884: 0x0040, 0x1885: 0x0f99,
+	0x1886: 0x2039, 0x1887: 0x0269, 0x1888: 0x01d9, 0x1889: 0x0fa9, 0x188a: 0x0fb9, 0x188b: 0x1089,
+	0x188c: 0x0279, 0x188d: 0x0369, 0x188e: 0x0289, 0x188f: 0x13d1, 0x1890: 0x0039, 0x1891: 0x0ee9,
+	0x1892: 0x1159, 0x1893: 0x0ef9, 0x1894: 0x0f09, 0x1895: 0x1199, 0x1896: 0x0f31, 0x1897: 0x0249,
+	0x1898: 0x0f41, 0x1899: 0x0259, 0x189a: 0x0f51, 0x189b: 0x0359, 0x189c: 0x0f61, 0x189d: 0x0f71,
+	0x189e: 0x00d9, 0x189f: 0x0f99, 0x18a0: 0x2039, 0x18a1: 0x0269, 0x18a2: 0x01d9, 0x18a3: 0x0fa9,
+	0x18a4: 0x0fb9, 0x18a5: 0x1089, 0x18a6: 0x0279, 0x18a7: 0x0369, 0x18a8: 0x0289, 0x18a9: 0x13d1,
+	0x18aa: 0x0039, 0x18ab: 0x0ee9, 0x18ac: 0x1159, 0x18ad: 0x0ef9, 0x18ae: 0x0f09, 0x18af: 0x1199,
+	0x18b0: 0x0f31, 0x18b1: 0x0249, 0x18b2: 0x0f41, 0x18b3: 0x0259, 0x18b4: 0x0f51, 0x18b5: 0x0359,
+	0x18b6: 0x0f61, 0x18b7: 0x0f71, 0x18b8: 0x00d9, 0x18b9: 0x0f99, 0x18ba: 0x2039, 0x18bb: 0x0269,
+	0x18bc: 0x01d9, 0x18bd: 0x0fa9, 0x18be: 0x0fb9, 0x18bf: 0x1089,
+	// Block 0x63, offset 0x18c0
+	0x18c0: 0x0279, 0x18c1: 0x0369, 0x18c2: 0x0289, 0x18c3: 0x13d1, 0x18c4: 0x0039, 0x18c5: 0x0ee9,
+	0x18c6: 0x0040, 0x18c7: 0x0ef9, 0x18c8: 0x0f09, 0x18c9: 0x1199, 0x18ca: 0x0f31, 0x18cb: 0x0040,
+	0x18cc: 0x0040, 0x18cd: 0x0259, 0x18ce: 0x0f51, 0x18cf: 0x0359, 0x18d0: 0x0f61, 0x18d1: 0x0f71,
+	0x18d2: 0x00d9, 0x18d3: 0x0f99, 0x18d4: 0x2039, 0x18d5: 0x0040, 0x18d6: 0x01d9, 0x18d7: 0x0fa9,
+	0x18d8: 0x0fb9, 0x18d9: 0x1089, 0x18da: 0x0279, 0x18db: 0x0369, 0x18dc: 0x0289, 0x18dd: 0x0040,
+	0x18de: 0x0039, 0x18df: 0x0ee9, 0x18e0: 0x1159, 0x18e1: 0x0ef9, 0x18e2: 0x0f09, 0x18e3: 0x1199,
+	0x18e4: 0x0f31, 0x18e5: 0x0249, 0x18e6: 0x0f41, 0x18e7: 0x0259, 0x18e8: 0x0f51, 0x18e9: 0x0359,
+	0x18ea: 0x0f61, 0x18eb: 0x0f71, 0x18ec: 0x00d9, 0x18ed: 0x0f99, 0x18ee: 0x2039, 0x18ef: 0x0269,
+	0x18f0: 0x01d9, 0x18f1: 0x0fa9, 0x18f2: 0x0fb9, 0x18f3: 0x1089, 0x18f4: 0x0279, 0x18f5: 0x0369,
+	0x18f6: 0x0289, 0x18f7: 0x13d1, 0x18f8: 0x0039, 0x18f9: 0x0ee9, 0x18fa: 0x0040, 0x18fb: 0x0ef9,
+	0x18fc: 0x0f09, 0x18fd: 0x1199, 0x18fe: 0x0f31, 0x18ff: 0x0040,
+	// Block 0x64, offset 0x1900
+	0x1900: 0x0f41, 0x1901: 0x0259, 0x1902: 0x0f51, 0x1903: 0x0359, 0x1904: 0x0f61, 0x1905: 0x0040,
+	0x1906: 0x00d9, 0x1907: 0x0040, 0x1908: 0x0040, 0x1909: 0x0040, 0x190a: 0x01d9, 0x190b: 0x0fa9,
+	0x190c: 0x0fb9, 0x190d: 0x1089, 0x190e: 0x0279, 0x190f: 0x0369, 0x1910: 0x0289, 0x1911: 0x0040,
+	0x1912: 0x0039, 0x1913: 0x0ee9, 0x1914: 0x1159, 0x1915: 0x0ef9, 0x1916: 0x0f09, 0x1917: 0x1199,
+	0x1918: 0x0f31, 0x1919: 0x0249, 0x191a: 0x0f41, 0x191b: 0x0259, 0x191c: 0x0f51, 0x191d: 0x0359,
+	0x191e: 0x0f61, 0x191f: 0x0f71, 0x1920: 0x00d9, 0x1921: 0x0f99, 0x1922: 0x2039, 0x1923: 0x0269,
+	0x1924: 0x01d9, 0x1925: 0x0fa9, 0x1926: 0x0fb9, 0x1927: 0x1089, 0x1928: 0x0279, 0x1929: 0x0369,
+	0x192a: 0x0289, 0x192b: 0x13d1, 0x192c: 0x0039, 0x192d: 0x0ee9, 0x192e: 0x1159, 0x192f: 0x0ef9,
+	0x1930: 0x0f09, 0x1931: 0x1199, 0x1932: 0x0f31, 0x1933: 0x0249, 0x1934: 0x0f41, 0x1935: 0x0259,
+	0x1936: 0x0f51, 0x1937: 0x0359, 0x1938: 0x0f61, 0x1939: 0x0f71, 0x193a: 0x00d9, 0x193b: 0x0f99,
+	0x193c: 0x2039, 0x193d: 0x0269, 0x193e: 0x01d9, 0x193f: 0x0fa9,
+	// Block 0x65, offset 0x1940
+	0x1940: 0x0fb9, 0x1941: 0x1089, 0x1942: 0x0279, 0x1943: 0x0369, 0x1944: 0x0289, 0x1945: 0x13d1,
+	0x1946: 0x0039, 0x1947: 0x0ee9, 0x1948: 0x1159, 0x1949: 0x0ef9, 0x194a: 0x0f09, 0x194b: 0x1199,
+	0x194c: 0x0f31, 0x194d: 0x0249, 0x194e: 0x0f41, 0x194f: 0x0259, 0x1950: 0x0f51, 0x1951: 0x0359,
+	0x1952: 0x0f61, 0x1953: 0x0f71, 0x1954: 0x00d9, 0x1955: 0x0f99, 0x1956: 0x2039, 0x1957: 0x0269,
+	0x1958: 0x01d9, 0x1959: 0x0fa9, 0x195a: 0x0fb9, 0x195b: 0x1089, 0x195c: 0x0279, 0x195d: 0x0369,
+	0x195e: 0x0289, 0x195f: 0x13d1, 0x1960: 0x0039, 0x1961: 0x0ee9, 0x1962: 0x1159, 0x1963: 0x0ef9,
+	0x1964: 0x0f09, 0x1965: 0x1199, 0x1966: 0x0f31, 0x1967: 0x0249, 0x1968: 0x0f41, 0x1969: 0x0259,
+	0x196a: 0x0f51, 0x196b: 0x0359, 0x196c: 0x0f61, 0x196d: 0x0f71, 0x196e: 0x00d9, 0x196f: 0x0f99,
+	0x1970: 0x2039, 0x1971: 0x0269, 0x1972: 0x01d9, 0x1973: 0x0fa9, 0x1974: 0x0fb9, 0x1975: 0x1089,
+	0x1976: 0x0279, 0x1977: 0x0369, 0x1978: 0x0289, 0x1979: 0x13d1, 0x197a: 0x0039, 0x197b: 0x0ee9,
+	0x197c: 0x1159, 0x197d: 0x0ef9, 0x197e: 0x0f09, 0x197f: 0x1199,
+	// Block 0x66, offset 0x1980
+	0x1980: 0x0f31, 0x1981: 0x0249, 0x1982: 0x0f41, 0x1983: 0x0259, 0x1984: 0x0f51, 0x1985: 0x0359,
+	0x1986: 0x0f61, 0x1987: 0x0f71, 0x1988: 0x00d9, 0x1989: 0x0f99, 0x198a: 0x2039, 0x198b: 0x0269,
+	0x198c: 0x01d9, 0x198d: 0x0fa9, 0x198e: 0x0fb9, 0x198f: 0x1089, 0x1990: 0x0279, 0x1991: 0x0369,
+	0x1992: 0x0289, 0x1993: 0x13d1, 0x1994: 0x0039, 0x1995: 0x0ee9, 0x1996: 0x1159, 0x1997: 0x0ef9,
+	0x1998: 0x0f09, 0x1999: 0x1199, 0x199a: 0x0f31, 0x199b: 0x0249, 0x199c: 0x0f41, 0x199d: 0x0259,
+	0x199e: 0x0f51, 0x199f: 0x0359, 0x19a0: 0x0f61, 0x19a1: 0x0f71, 0x19a2: 0x00d9, 0x19a3: 0x0f99,
+	0x19a4: 0x2039, 0x19a5: 0x0269, 0x19a6: 0x01d9, 0x19a7: 0x0fa9, 0x19a8: 0x0fb9, 0x19a9: 0x1089,
+	0x19aa: 0x0279, 0x19ab: 0x0369, 0x19ac: 0x0289, 0x19ad: 0x13d1, 0x19ae: 0x0039, 0x19af: 0x0ee9,
+	0x19b0: 0x1159, 0x19b1: 0x0ef9, 0x19b2: 0x0f09, 0x19b3: 0x1199, 0x19b4: 0x0f31, 0x19b5: 0x0249,
+	0x19b6: 0x0f41, 0x19b7: 0x0259, 0x19b8: 0x0f51, 0x19b9: 0x0359, 0x19ba: 0x0f61, 0x19bb: 0x0f71,
+	0x19bc: 0x00d9, 0x19bd: 0x0f99, 0x19be: 0x2039, 0x19bf: 0x0269,
+	// Block 0x67, offset 0x19c0
+	0x19c0: 0x01d9, 0x19c1: 0x0fa9, 0x19c2: 0x0fb9, 0x19c3: 0x1089, 0x19c4: 0x0279, 0x19c5: 0x0369,
+	0x19c6: 0x0289, 0x19c7: 0x13d1, 0x19c8: 0x0039, 0x19c9: 0x0ee9, 0x19ca: 0x1159, 0x19cb: 0x0ef9,
+	0x19cc: 0x0f09, 0x19cd: 0x1199, 0x19ce: 0x0f31, 0x19cf: 0x0249, 0x19d0: 0x0f41, 0x19d1: 0x0259,
+	0x19d2: 0x0f51, 0x19d3: 0x0359, 0x19d4: 0x0f61, 0x19d5: 0x0f71, 0x19d6: 0x00d9, 0x19d7: 0x0f99,
+	0x19d8: 0x2039, 0x19d9: 0x0269, 0x19da: 0x01d9, 0x19db: 0x0fa9, 0x19dc: 0x0fb9, 0x19dd: 0x1089,
+	0x19de: 0x0279, 0x19df: 0x0369, 0x19e0: 0x0289, 0x19e1: 0x13d1, 0x19e2: 0x0039, 0x19e3: 0x0ee9,
+	0x19e4: 0x1159, 0x19e5: 0x0ef9, 0x19e6: 0x0f09, 0x19e7: 0x1199, 0x19e8: 0x0f31, 0x19e9: 0x0249,
+	0x19ea: 0x0f41, 0x19eb: 0x0259, 0x19ec: 0x0f51, 0x19ed: 0x0359, 0x19ee: 0x0f61, 0x19ef: 0x0f71,
+	0x19f0: 0x00d9, 0x19f1: 0x0f99, 0x19f2: 0x2039, 0x19f3: 0x0269, 0x19f4: 0x01d9, 0x19f5: 0x0fa9,
+	0x19f6: 0x0fb9, 0x19f7: 0x1089, 0x19f8: 0x0279, 0x19f9: 0x0369, 0x19fa: 0x0289, 0x19fb: 0x13d1,
+	0x19fc: 0x0039, 0x19fd: 0x0ee9, 0x19fe: 0x1159, 0x19ff: 0x0ef9,
+	// Block 0x68, offset 0x1a00
+	0x1a00: 0x0f09, 0x1a01: 0x1199, 0x1a02: 0x0f31, 0x1a03: 0x0249, 0x1a04: 0x0f41, 0x1a05: 0x0259,
+	0x1a06: 0x0f51, 0x1a07: 0x0359, 0x1a08: 0x0f61, 0x1a09: 0x0f71, 0x1a0a: 0x00d9, 0x1a0b: 0x0f99,
+	0x1a0c: 0x2039, 0x1a0d: 0x0269, 0x1a0e: 0x01d9, 0x1a0f: 0x0fa9, 0x1a10: 0x0fb9, 0x1a11: 0x1089,
+	0x1a12: 0x0279, 0x1a13: 0x0369, 0x1a14: 0x0289, 0x1a15: 0x13d1, 0x1a16: 0x0039, 0x1a17: 0x0ee9,
+	0x1a18: 0x1159, 0x1a19: 0x0ef9, 0x1a1a: 0x0f09, 0x1a1b: 0x1199, 0x1a1c: 0x0f31, 0x1a1d: 0x0249,
+	0x1a1e: 0x0f41, 0x1a1f: 0x0259, 0x1a20: 0x0f51, 0x1a21: 0x0359, 0x1a22: 0x0f61, 0x1a23: 0x0f71,
+	0x1a24: 0x00d9, 0x1a25: 0x0f99, 0x1a26: 0x2039, 0x1a27: 0x0269, 0x1a28: 0x01d9, 0x1a29: 0x0fa9,
+	0x1a2a: 0x0fb9, 0x1a2b: 0x1089, 0x1a2c: 0x0279, 0x1a2d: 0x0369, 0x1a2e: 0x0289, 0x1a2f: 0x13d1,
+	0x1a30: 0x0039, 0x1a31: 0x0ee9, 0x1a32: 0x1159, 0x1a33: 0x0ef9, 0x1a34: 0x0f09, 0x1a35: 0x1199,
+	0x1a36: 0x0f31, 0x1a37: 0x0249, 0x1a38: 0x0f41, 0x1a39: 0x0259, 0x1a3a: 0x0f51, 0x1a3b: 0x0359,
+	0x1a3c: 0x0f61, 0x1a3d: 0x0f71, 0x1a3e: 0x00d9, 0x1a3f: 0x0f99,
+	// Block 0x69, offset 0x1a40
+	0x1a40: 0x2039, 0x1a41: 0x0269, 0x1a42: 0x01d9, 0x1a43: 0x0fa9, 0x1a44: 0x0fb9, 0x1a45: 0x1089,
+	0x1a46: 0x0279, 0x1a47: 0x0369, 0x1a48: 0x0289, 0x1a49: 0x13d1, 0x1a4a: 0x0039, 0x1a4b: 0x0ee9,
+	0x1a4c: 0x1159, 0x1a4d: 0x0ef9, 0x1a4e: 0x0f09, 0x1a4f: 0x1199, 0x1a50: 0x0f31, 0x1a51: 0x0249,
+	0x1a52: 0x0f41, 0x1a53: 0x0259, 0x1a54: 0x0f51, 0x1a55: 0x0359, 0x1a56: 0x0f61, 0x1a57: 0x0f71,
+	0x1a58: 0x00d9, 0x1a59: 0x0f99, 0x1a5a: 0x2039, 0x1a5b: 0x0269, 0x1a5c: 0x01d9, 0x1a5d: 0x0fa9,
+	0x1a5e: 0x0fb9, 0x1a5f: 0x1089, 0x1a60: 0x0279, 0x1a61: 0x0369, 0x1a62: 0x0289, 0x1a63: 0x13d1,
+	0x1a64: 0xba81, 0x1a65: 0xba99, 0x1a66: 0x0040, 0x1a67: 0x0040, 0x1a68: 0xbab1, 0x1a69: 0x1099,
+	0x1a6a: 0x10b1, 0x1a6b: 0x10c9, 0x1a6c: 0xbac9, 0x1a6d: 0xbae1, 0x1a6e: 0xbaf9, 0x1a6f: 0x1429,
+	0x1a70: 0x1a31, 0x1a71: 0xbb11, 0x1a72: 0xbb29, 0x1a73: 0xbb41, 0x1a74: 0xbb59, 0x1a75: 0xbb71,
+	0x1a76: 0xbb89, 0x1a77: 0x2109, 0x1a78: 0x1111, 0x1a79: 0x1429, 0x1a7a: 0xbba1, 0x1a7b: 0xbbb9,
+	0x1a7c: 0xbbd1, 0x1a7d: 0x10e1, 0x1a7e: 0x10f9, 0x1a7f: 0xbbe9,
+	// Block 0x6a, offset 0x1a80
+	0x1a80: 0x2079, 0x1a81: 0xbc01, 0x1a82: 0xbab1, 0x1a83: 0x1099, 0x1a84: 0x10b1, 0x1a85: 0x10c9,
+	0x1a86: 0xbac9, 0x1a87: 0xbae1, 0x1a88: 0xbaf9, 0x1a89: 0x1429, 0x1a8a: 0x1a31, 0x1a8b: 0xbb11,
+	0x1a8c: 0xbb29, 0x1a8d: 0xbb41, 0x1a8e: 0xbb59, 0x1a8f: 0xbb71, 0x1a90: 0xbb89, 0x1a91: 0x2109,
+	0x1a92: 0x1111, 0x1a93: 0xbba1, 0x1a94: 0xbba1, 0x1a95: 0xbbb9, 0x1a96: 0xbbd1, 0x1a97: 0x10e1,
+	0x1a98: 0x10f9, 0x1a99: 0xbbe9, 0x1a9a: 0x2079, 0x1a9b: 0xbc21, 0x1a9c: 0xbac9, 0x1a9d: 0x1429,
+	0x1a9e: 0xbb11, 0x1a9f: 0x10e1, 0x1aa0: 0x1111, 0x1aa1: 0x2109, 0x1aa2: 0xbab1, 0x1aa3: 0x1099,
+	0x1aa4: 0x10b1, 0x1aa5: 0x10c9, 0x1aa6: 0xbac9, 0x1aa7: 0xbae1, 0x1aa8: 0xbaf9, 0x1aa9: 0x1429,
+	0x1aaa: 0x1a31, 0x1aab: 0xbb11, 0x1aac: 0xbb29, 0x1aad: 0xbb41, 0x1aae: 0xbb59, 0x1aaf: 0xbb71,
+	0x1ab0: 0xbb89, 0x1ab1: 0x2109, 0x1ab2: 0x1111, 0x1ab3: 0x1429, 0x1ab4: 0xbba1, 0x1ab5: 0xbbb9,
+	0x1ab6: 0xbbd1, 0x1ab7: 0x10e1, 0x1ab8: 0x10f9, 0x1ab9: 0xbbe9, 0x1aba: 0x2079, 0x1abb: 0xbc01,
+	0x1abc: 0xbab1, 0x1abd: 0x1099, 0x1abe: 0x10b1, 0x1abf: 0x10c9,
+	// Block 0x6b, offset 0x1ac0
+	0x1ac0: 0xbac9, 0x1ac1: 0xbae1, 0x1ac2: 0xbaf9, 0x1ac3: 0x1429, 0x1ac4: 0x1a31, 0x1ac5: 0xbb11,
+	0x1ac6: 0xbb29, 0x1ac7: 0xbb41, 0x1ac8: 0xbb59, 0x1ac9: 0xbb71, 0x1aca: 0xbb89, 0x1acb: 0x2109,
+	0x1acc: 0x1111, 0x1acd: 0xbba1, 0x1ace: 0xbba1, 0x1acf: 0xbbb9, 0x1ad0: 0xbbd1, 0x1ad1: 0x10e1,
+	0x1ad2: 0x10f9, 0x1ad3: 0xbbe9, 0x1ad4: 0x2079, 0x1ad5: 0xbc21, 0x1ad6: 0xbac9, 0x1ad7: 0x1429,
+	0x1ad8: 0xbb11, 0x1ad9: 0x10e1, 0x1ada: 0x1111, 0x1adb: 0x2109, 0x1adc: 0xbab1, 0x1add: 0x1099,
+	0x1ade: 0x10b1, 0x1adf: 0x10c9, 0x1ae0: 0xbac9, 0x1ae1: 0xbae1, 0x1ae2: 0xbaf9, 0x1ae3: 0x1429,
+	0x1ae4: 0x1a31, 0x1ae5: 0xbb11, 0x1ae6: 0xbb29, 0x1ae7: 0xbb41, 0x1ae8: 0xbb59, 0x1ae9: 0xbb71,
+	0x1aea: 0xbb89, 0x1aeb: 0x2109, 0x1aec: 0x1111, 0x1aed: 0x1429, 0x1aee: 0xbba1, 0x1aef: 0xbbb9,
+	0x1af0: 0xbbd1, 0x1af1: 0x10e1, 0x1af2: 0x10f9, 0x1af3: 0xbbe9, 0x1af4: 0x2079, 0x1af5: 0xbc01,
+	0x1af6: 0xbab1, 0x1af7: 0x1099, 0x1af8: 0x10b1, 0x1af9: 0x10c9, 0x1afa: 0xbac9, 0x1afb: 0xbae1,
+	0x1afc: 0xbaf9, 0x1afd: 0x1429, 0x1afe: 0x1a31, 0x1aff: 0xbb11,
+	// Block 0x6c, offset 0x1b00
+	0x1b00: 0xbb29, 0x1b01: 0xbb41, 0x1b02: 0xbb59, 0x1b03: 0xbb71, 0x1b04: 0xbb89, 0x1b05: 0x2109,
+	0x1b06: 0x1111, 0x1b07: 0xbba1, 0x1b08: 0xbba1, 0x1b09: 0xbbb9, 0x1b0a: 0xbbd1, 0x1b0b: 0x10e1,
+	0x1b0c: 0x10f9, 0x1b0d: 0xbbe9, 0x1b0e: 0x2079, 0x1b0f: 0xbc21, 0x1b10: 0xbac9, 0x1b11: 0x1429,
+	0x1b12: 0xbb11, 0x1b13: 0x10e1, 0x1b14: 0x1111, 0x1b15: 0x2109, 0x1b16: 0xbab1, 0x1b17: 0x1099,
+	0x1b18: 0x10b1, 0x1b19: 0x10c9, 0x1b1a: 0xbac9, 0x1b1b: 0xbae1, 0x1b1c: 0xbaf9, 0x1b1d: 0x1429,
+	0x1b1e: 0x1a31, 0x1b1f: 0xbb11, 0x1b20: 0xbb29, 0x1b21: 0xbb41, 0x1b22: 0xbb59, 0x1b23: 0xbb71,
+	0x1b24: 0xbb89, 0x1b25: 0x2109, 0x1b26: 0x1111, 0x1b27: 0x1429, 0x1b28: 0xbba1, 0x1b29: 0xbbb9,
+	0x1b2a: 0xbbd1, 0x1b2b: 0x10e1, 0x1b2c: 0x10f9, 0x1b2d: 0xbbe9, 0x1b2e: 0x2079, 0x1b2f: 0xbc01,
+	0x1b30: 0xbab1, 0x1b31: 0x1099, 0x1b32: 0x10b1, 0x1b33: 0x10c9, 0x1b34: 0xbac9, 0x1b35: 0xbae1,
+	0x1b36: 0xbaf9, 0x1b37: 0x1429, 0x1b38: 0x1a31, 0x1b39: 0xbb11, 0x1b3a: 0xbb29, 0x1b3b: 0xbb41,
+	0x1b3c: 0xbb59, 0x1b3d: 0xbb71, 0x1b3e: 0xbb89, 0x1b3f: 0x2109,
+	// Block 0x6d, offset 0x1b40
+	0x1b40: 0x1111, 0x1b41: 0xbba1, 0x1b42: 0xbba1, 0x1b43: 0xbbb9, 0x1b44: 0xbbd1, 0x1b45: 0x10e1,
+	0x1b46: 0x10f9, 0x1b47: 0xbbe9, 0x1b48: 0x2079, 0x1b49: 0xbc21, 0x1b4a: 0xbac9, 0x1b4b: 0x1429,
+	0x1b4c: 0xbb11, 0x1b4d: 0x10e1, 0x1b4e: 0x1111, 0x1b4f: 0x2109, 0x1b50: 0xbab1, 0x1b51: 0x1099,
+	0x1b52: 0x10b1, 0x1b53: 0x10c9, 0x1b54: 0xbac9, 0x1b55: 0xbae1, 0x1b56: 0xbaf9, 0x1b57: 0x1429,
+	0x1b58: 0x1a31, 0x1b59: 0xbb11, 0x1b5a: 0xbb29, 0x1b5b: 0xbb41, 0x1b5c: 0xbb59, 0x1b5d: 0xbb71,
+	0x1b5e: 0xbb89, 0x1b5f: 0x2109, 0x1b60: 0x1111, 0x1b61: 0x1429, 0x1b62: 0xbba1, 0x1b63: 0xbbb9,
+	0x1b64: 0xbbd1, 0x1b65: 0x10e1, 0x1b66: 0x10f9, 0x1b67: 0xbbe9, 0x1b68: 0x2079, 0x1b69: 0xbc01,
+	0x1b6a: 0xbab1, 0x1b6b: 0x1099, 0x1b6c: 0x10b1, 0x1b6d: 0x10c9, 0x1b6e: 0xbac9, 0x1b6f: 0xbae1,
+	0x1b70: 0xbaf9, 0x1b71: 0x1429, 0x1b72: 0x1a31, 0x1b73: 0xbb11, 0x1b74: 0xbb29, 0x1b75: 0xbb41,
+	0x1b76: 0xbb59, 0x1b77: 0xbb71, 0x1b78: 0xbb89, 0x1b79: 0x2109, 0x1b7a: 0x1111, 0x1b7b: 0xbba1,
+	0x1b7c: 0xbba1, 0x1b7d: 0xbbb9, 0x1b7e: 0xbbd1, 0x1b7f: 0x10e1,
+	// Block 0x6e, offset 0x1b80
+	0x1b80: 0x10f9, 0x1b81: 0xbbe9, 0x1b82: 0x2079, 0x1b83: 0xbc21, 0x1b84: 0xbac9, 0x1b85: 0x1429,
+	0x1b86: 0xbb11, 0x1b87: 0x10e1, 0x1b88: 0x1111, 0x1b89: 0x2109, 0x1b8a: 0xbc41, 0x1b8b: 0xbc41,
+	0x1b8c: 0x0040, 0x1b8d: 0x0040, 0x1b8e: 0x1f41, 0x1b8f: 0x00c9, 0x1b90: 0x0069, 0x1b91: 0x0079,
+	0x1b92: 0x1f51, 0x1b93: 0x1f61, 0x1b94: 0x1f71, 0x1b95: 0x1f81, 0x1b96: 0x1f91, 0x1b97: 0x1fa1,
+	0x1b98: 0x1f41, 0x1b99: 0x00c9, 0x1b9a: 0x0069, 0x1b9b: 0x0079, 0x1b9c: 0x1f51, 0x1b9d: 0x1f61,
+	0x1b9e: 0x1f71, 0x1b9f: 0x1f81, 0x1ba0: 0x1f91, 0x1ba1: 0x1fa1, 0x1ba2: 0x1f41, 0x1ba3: 0x00c9,
+	0x1ba4: 0x0069, 0x1ba5: 0x0079, 0x1ba6: 0x1f51, 0x1ba7: 0x1f61, 0x1ba8: 0x1f71, 0x1ba9: 0x1f81,
+	0x1baa: 0x1f91, 0x1bab: 0x1fa1, 0x1bac: 0x1f41, 0x1bad: 0x00c9, 0x1bae: 0x0069, 0x1baf: 0x0079,
+	0x1bb0: 0x1f51, 0x1bb1: 0x1f61, 0x1bb2: 0x1f71, 0x1bb3: 0x1f81, 0x1bb4: 0x1f91, 0x1bb5: 0x1fa1,
+	0x1bb6: 0x1f41, 0x1bb7: 0x00c9, 0x1bb8: 0x0069, 0x1bb9: 0x0079, 0x1bba: 0x1f51, 0x1bbb: 0x1f61,
+	0x1bbc: 0x1f71, 0x1bbd: 0x1f81, 0x1bbe: 0x1f91, 0x1bbf: 0x1fa1,
+	// Block 0x6f, offset 0x1bc0
+	0x1bc0: 0xe115, 0x1bc1: 0xe115, 0x1bc2: 0xe135, 0x1bc3: 0xe135, 0x1bc4: 0xe115, 0x1bc5: 0xe115,
+	0x1bc6: 0xe175, 0x1bc7: 0xe175, 0x1bc8: 0xe115, 0x1bc9: 0xe115, 0x1bca: 0xe135, 0x1bcb: 0xe135,
+	0x1bcc: 0xe115, 0x1bcd: 0xe115, 0x1bce: 0xe1f5, 0x1bcf: 0xe1f5, 0x1bd0: 0xe115, 0x1bd1: 0xe115,
+	0x1bd2: 0xe135, 0x1bd3: 0xe135, 0x1bd4: 0xe115, 0x1bd5: 0xe115, 0x1bd6: 0xe175, 0x1bd7: 0xe175,
+	0x1bd8: 0xe115, 0x1bd9: 0xe115, 0x1bda: 0xe135, 0x1bdb: 0xe135, 0x1bdc: 0xe115, 0x1bdd: 0xe115,
+	0x1bde: 0x8b05, 0x1bdf: 0x8b05, 0x1be0: 0x04b5, 0x1be1: 0x04b5, 0x1be2: 0x0208, 0x1be3: 0x0208,
+	0x1be4: 0x0208, 0x1be5: 0x0208, 0x1be6: 0x0208, 0x1be7: 0x0208, 0x1be8: 0x0208, 0x1be9: 0x0208,
+	0x1bea: 0x0208, 0x1beb: 0x0208, 0x1bec: 0x0208, 0x1bed: 0x0208, 0x1bee: 0x0208, 0x1bef: 0x0208,
+	0x1bf0: 0x0208, 0x1bf1: 0x0208, 0x1bf2: 0x0208, 0x1bf3: 0x0208, 0x1bf4: 0x0208, 0x1bf5: 0x0208,
+	0x1bf6: 0x0208, 0x1bf7: 0x0208, 0x1bf8: 0x0208, 0x1bf9: 0x0208, 0x1bfa: 0x0208, 0x1bfb: 0x0208,
+	0x1bfc: 0x0208, 0x1bfd: 0x0208, 0x1bfe: 0x0208, 0x1bff: 0x0208,
+	// Block 0x70, offset 0x1c00
+	0x1c00: 0xb189, 0x1c01: 0xb1a1, 0x1c02: 0xb201, 0x1c03: 0xb249, 0x1c04: 0x0040, 0x1c05: 0xb411,
+	0x1c06: 0xb291, 0x1c07: 0xb219, 0x1c08: 0xb309, 0x1c09: 0xb429, 0x1c0a: 0xb399, 0x1c0b: 0xb3b1,
+	0x1c0c: 0xb3c9, 0x1c0d: 0xb3e1, 0x1c0e: 0xb2a9, 0x1c0f: 0xb339, 0x1c10: 0xb369, 0x1c11: 0xb2d9,
+	0x1c12: 0xb381, 0x1c13: 0xb279, 0x1c14: 0xb2c1, 0x1c15: 0xb1d1, 0x1c16: 0xb1e9, 0x1c17: 0xb231,
+	0x1c18: 0xb261, 0x1c19: 0xb2f1, 0x1c1a: 0xb321, 0x1c1b: 0xb351, 0x1c1c: 0xbc59, 0x1c1d: 0x7949,
+	0x1c1e: 0xbc71, 0x1c1f: 0xbc89, 0x1c20: 0x0040, 0x1c21: 0xb1a1, 0x1c22: 0xb201, 0x1c23: 0x0040,
+	0x1c24: 0xb3f9, 0x1c25: 0x0040, 0x1c26: 0x0040, 0x1c27: 0xb219, 0x1c28: 0x0040, 0x1c29: 0xb429,
+	0x1c2a: 0xb399, 0x1c2b: 0xb3b1, 0x1c2c: 0xb3c9, 0x1c2d: 0xb3e1, 0x1c2e: 0xb2a9, 0x1c2f: 0xb339,
+	0x1c30: 0xb369, 0x1c31: 0xb2d9, 0x1c32: 0xb381, 0x1c33: 0x0040, 0x1c34: 0xb2c1, 0x1c35: 0xb1d1,
+	0x1c36: 0xb1e9, 0x1c37: 0xb231, 0x1c38: 0x0040, 0x1c39: 0xb2f1, 0x1c3a: 0x0040, 0x1c3b: 0xb351,
+	0x1c3c: 0x0040, 0x1c3d: 0x0040, 0x1c3e: 0x0040, 0x1c3f: 0x0040,
+	// Block 0x71, offset 0x1c40
+	0x1c40: 0x0040, 0x1c41: 0x0040, 0x1c42: 0xb201, 0x1c43: 0x0040, 0x1c44: 0x0040, 0x1c45: 0x0040,
+	0x1c46: 0x0040, 0x1c47: 0xb219, 0x1c48: 0x0040, 0x1c49: 0xb429, 0x1c4a: 0x0040, 0x1c4b: 0xb3b1,
+	0x1c4c: 0x0040, 0x1c4d: 0xb3e1, 0x1c4e: 0xb2a9, 0x1c4f: 0xb339, 0x1c50: 0x0040, 0x1c51: 0xb2d9,
+	0x1c52: 0xb381, 0x1c53: 0x0040, 0x1c54: 0xb2c1, 0x1c55: 0x0040, 0x1c56: 0x0040, 0x1c57: 0xb231,
+	0x1c58: 0x0040, 0x1c59: 0xb2f1, 0x1c5a: 0x0040, 0x1c5b: 0xb351, 0x1c5c: 0x0040, 0x1c5d: 0x7949,
+	0x1c5e: 0x0040, 0x1c5f: 0xbc89, 0x1c60: 0x0040, 0x1c61: 0xb1a1, 0x1c62: 0xb201, 0x1c63: 0x0040,
+	0x1c64: 0xb3f9, 0x1c65: 0x0040, 0x1c66: 0x0040, 0x1c67: 0xb219, 0x1c68: 0xb309, 0x1c69: 0xb429,
+	0x1c6a: 0xb399, 0x1c6b: 0x0040, 0x1c6c: 0xb3c9, 0x1c6d: 0xb3e1, 0x1c6e: 0xb2a9, 0x1c6f: 0xb339,
+	0x1c70: 0xb369, 0x1c71: 0xb2d9, 0x1c72: 0xb381, 0x1c73: 0x0040, 0x1c74: 0xb2c1, 0x1c75: 0xb1d1,
+	0x1c76: 0xb1e9, 0x1c77: 0xb231, 0x1c78: 0x0040, 0x1c79: 0xb2f1, 0x1c7a: 0xb321, 0x1c7b: 0xb351,
+	0x1c7c: 0xbc59, 0x1c7d: 0x0040, 0x1c7e: 0xbc71, 0x1c7f: 0x0040,
+	// Block 0x72, offset 0x1c80
+	0x1c80: 0xb189, 0x1c81: 0xb1a1, 0x1c82: 0xb201, 0x1c83: 0xb249, 0x1c84: 0xb3f9, 0x1c85: 0xb411,
+	0x1c86: 0xb291, 0x1c87: 0xb219, 0x1c88: 0xb309, 0x1c89: 0xb429, 0x1c8a: 0x0040, 0x1c8b: 0xb3b1,
+	0x1c8c: 0xb3c9, 0x1c8d: 0xb3e1, 0x1c8e: 0xb2a9, 0x1c8f: 0xb339, 0x1c90: 0xb369, 0x1c91: 0xb2d9,
+	0x1c92: 0xb381, 0x1c93: 0xb279, 0x1c94: 0xb2c1, 0x1c95: 0xb1d1, 0x1c96: 0xb1e9, 0x1c97: 0xb231,
+	0x1c98: 0xb261, 0x1c99: 0xb2f1, 0x1c9a: 0xb321, 0x1c9b: 0xb351, 0x1c9c: 0x0040, 0x1c9d: 0x0040,
+	0x1c9e: 0x0040, 0x1c9f: 0x0040, 0x1ca0: 0x0040, 0x1ca1: 0xb1a1, 0x1ca2: 0xb201, 0x1ca3: 0xb249,
+	0x1ca4: 0x0040, 0x1ca5: 0xb411, 0x1ca6: 0xb291, 0x1ca7: 0xb219, 0x1ca8: 0xb309, 0x1ca9: 0xb429,
+	0x1caa: 0x0040, 0x1cab: 0xb3b1, 0x1cac: 0xb3c9, 0x1cad: 0xb3e1, 0x1cae: 0xb2a9, 0x1caf: 0xb339,
+	0x1cb0: 0xb369, 0x1cb1: 0xb2d9, 0x1cb2: 0xb381, 0x1cb3: 0xb279, 0x1cb4: 0xb2c1, 0x1cb5: 0xb1d1,
+	0x1cb6: 0xb1e9, 0x1cb7: 0xb231, 0x1cb8: 0xb261, 0x1cb9: 0xb2f1, 0x1cba: 0xb321, 0x1cbb: 0xb351,
+	0x1cbc: 0x0040, 0x1cbd: 0x0040, 0x1cbe: 0x0040, 0x1cbf: 0x0040,
+	// Block 0x73, offset 0x1cc0
+	0x1cc0: 0x0040, 0x1cc1: 0xbca2, 0x1cc2: 0xbcba, 0x1cc3: 0xbcd2, 0x1cc4: 0xbcea, 0x1cc5: 0xbd02,
+	0x1cc6: 0xbd1a, 0x1cc7: 0xbd32, 0x1cc8: 0xbd4a, 0x1cc9: 0xbd62, 0x1cca: 0xbd7a, 0x1ccb: 0x0018,
+	0x1ccc: 0x0018, 0x1ccd: 0x0040, 0x1cce: 0x0040, 0x1ccf: 0x0040, 0x1cd0: 0xbd92, 0x1cd1: 0xbdb2,
+	0x1cd2: 0xbdd2, 0x1cd3: 0xbdf2, 0x1cd4: 0xbe12, 0x1cd5: 0xbe32, 0x1cd6: 0xbe52, 0x1cd7: 0xbe72,
+	0x1cd8: 0xbe92, 0x1cd9: 0xbeb2, 0x1cda: 0xbed2, 0x1cdb: 0xbef2, 0x1cdc: 0xbf12, 0x1cdd: 0xbf32,
+	0x1cde: 0xbf52, 0x1cdf: 0xbf72, 0x1ce0: 0xbf92, 0x1ce1: 0xbfb2, 0x1ce2: 0xbfd2, 0x1ce3: 0xbff2,
+	0x1ce4: 0xc012, 0x1ce5: 0xc032, 0x1ce6: 0xc052, 0x1ce7: 0xc072, 0x1ce8: 0xc092, 0x1ce9: 0xc0b2,
+	0x1cea: 0xc0d1, 0x1ceb: 0x1159, 0x1cec: 0x0269, 0x1ced: 0x6671, 0x1cee: 0xc111, 0x1cef: 0x0040,
+	0x1cf0: 0x0039, 0x1cf1: 0x0ee9, 0x1cf2: 0x1159, 0x1cf3: 0x0ef9, 0x1cf4: 0x0f09, 0x1cf5: 0x1199,
+	0x1cf6: 0x0f31, 0x1cf7: 0x0249, 0x1cf8: 0x0f41, 0x1cf9: 0x0259, 0x1cfa: 0x0f51, 0x1cfb: 0x0359,
+	0x1cfc: 0x0f61, 0x1cfd: 0x0f71, 0x1cfe: 0x00d9, 0x1cff: 0x0f99,
+	// Block 0x74, offset 0x1d00
+	0x1d00: 0x2039, 0x1d01: 0x0269, 0x1d02: 0x01d9, 0x1d03: 0x0fa9, 0x1d04: 0x0fb9, 0x1d05: 0x1089,
+	0x1d06: 0x0279, 0x1d07: 0x0369, 0x1d08: 0x0289, 0x1d09: 0x13d1, 0x1d0a: 0xc129, 0x1d0b: 0x65b1,
+	0x1d0c: 0xc141, 0x1d0d: 0x1441, 0x1d0e: 0xc159, 0x1d0f: 0xc179, 0x1d10: 0x0018, 0x1d11: 0x0018,
+	0x1d12: 0x0018, 0x1d13: 0x0018, 0x1d14: 0x0018, 0x1d15: 0x0018, 0x1d16: 0x0018, 0x1d17: 0x0018,
+	0x1d18: 0x0018, 0x1d19: 0x0018, 0x1d1a: 0x0018, 0x1d1b: 0x0018, 0x1d1c: 0x0018, 0x1d1d: 0x0018,
+	0x1d1e: 0x0018, 0x1d1f: 0x0018, 0x1d20: 0x0018, 0x1d21: 0x0018, 0x1d22: 0x0018, 0x1d23: 0x0018,
+	0x1d24: 0x0018, 0x1d25: 0x0018, 0x1d26: 0x0018, 0x1d27: 0x0018, 0x1d28: 0x0018, 0x1d29: 0x0018,
+	0x1d2a: 0xc191, 0x1d2b: 0xc1a9, 0x1d2c: 0x0040, 0x1d2d: 0x0040, 0x1d2e: 0x0040, 0x1d2f: 0x0040,
+	0x1d30: 0x0018, 0x1d31: 0x0018, 0x1d32: 0x0018, 0x1d33: 0x0018, 0x1d34: 0x0018, 0x1d35: 0x0018,
+	0x1d36: 0x0018, 0x1d37: 0x0018, 0x1d38: 0x0018, 0x1d39: 0x0018, 0x1d3a: 0x0018, 0x1d3b: 0x0018,
+	0x1d3c: 0x0018, 0x1d3d: 0x0018, 0x1d3e: 0x0018, 0x1d3f: 0x0018,
+	// Block 0x75, offset 0x1d40
+	0x1d40: 0xc1d9, 0x1d41: 0xc211, 0x1d42: 0xc249, 0x1d43: 0x0040, 0x1d44: 0x0040, 0x1d45: 0x0040,
+	0x1d46: 0x0040, 0x1d47: 0x0040, 0x1d48: 0x0040, 0x1d49: 0x0040, 0x1d4a: 0x0040, 0x1d4b: 0x0040,
+	0x1d4c: 0x0040, 0x1d4d: 0x0040, 0x1d4e: 0x0040, 0x1d4f: 0x0040, 0x1d50: 0xc269, 0x1d51: 0xc289,
+	0x1d52: 0xc2a9, 0x1d53: 0xc2c9, 0x1d54: 0xc2e9, 0x1d55: 0xc309, 0x1d56: 0xc329, 0x1d57: 0xc349,
+	0x1d58: 0xc369, 0x1d59: 0xc389, 0x1d5a: 0xc3a9, 0x1d5b: 0xc3c9, 0x1d5c: 0xc3e9, 0x1d5d: 0xc409,
+	0x1d5e: 0xc429, 0x1d5f: 0xc449, 0x1d60: 0xc469, 0x1d61: 0xc489, 0x1d62: 0xc4a9, 0x1d63: 0xc4c9,
+	0x1d64: 0xc4e9, 0x1d65: 0xc509, 0x1d66: 0xc529, 0x1d67: 0xc549, 0x1d68: 0xc569, 0x1d69: 0xc589,
+	0x1d6a: 0xc5a9, 0x1d6b: 0xc5c9, 0x1d6c: 0xc5e9, 0x1d6d: 0xc609, 0x1d6e: 0xc629, 0x1d6f: 0xc649,
+	0x1d70: 0xc669, 0x1d71: 0xc689, 0x1d72: 0xc6a9, 0x1d73: 0xc6c9, 0x1d74: 0xc6e9, 0x1d75: 0xc709,
+	0x1d76: 0xc729, 0x1d77: 0xc749, 0x1d78: 0xc769, 0x1d79: 0xc789, 0x1d7a: 0xc7a9, 0x1d7b: 0xc7c9,
+	0x1d7c: 0x0040, 0x1d7d: 0x0040, 0x1d7e: 0x0040, 0x1d7f: 0x0040,
+	// Block 0x76, offset 0x1d80
+	0x1d80: 0xcaf9, 0x1d81: 0xcb19, 0x1d82: 0xcb39, 0x1d83: 0x8b1d, 0x1d84: 0xcb59, 0x1d85: 0xcb79,
+	0x1d86: 0xcb99, 0x1d87: 0xcbb9, 0x1d88: 0xcbd9, 0x1d89: 0xcbf9, 0x1d8a: 0xcc19, 0x1d8b: 0xcc39,
+	0x1d8c: 0xcc59, 0x1d8d: 0x8b3d, 0x1d8e: 0xcc79, 0x1d8f: 0xcc99, 0x1d90: 0xccb9, 0x1d91: 0xccd9,
+	0x1d92: 0x8b5d, 0x1d93: 0xccf9, 0x1d94: 0xcd19, 0x1d95: 0xc429, 0x1d96: 0x8b7d, 0x1d97: 0xcd39,
+	0x1d98: 0xcd59, 0x1d99: 0xcd79, 0x1d9a: 0xcd99, 0x1d9b: 0xcdb9, 0x1d9c: 0x8b9d, 0x1d9d: 0xcdd9,
+	0x1d9e: 0xcdf9, 0x1d9f: 0xce19, 0x1da0: 0xce39, 0x1da1: 0xce59, 0x1da2: 0xc789, 0x1da3: 0xce79,
+	0x1da4: 0xce99, 0x1da5: 0xceb9, 0x1da6: 0xced9, 0x1da7: 0xcef9, 0x1da8: 0xcf19, 0x1da9: 0xcf39,
+	0x1daa: 0xcf59, 0x1dab: 0xcf79, 0x1dac: 0xcf99, 0x1dad: 0xcfb9, 0x1dae: 0xcfd9, 0x1daf: 0xcff9,
+	0x1db0: 0xd019, 0x1db1: 0xd039, 0x1db2: 0xd039, 0x1db3: 0xd039, 0x1db4: 0x8bbd, 0x1db5: 0xd059,
+	0x1db6: 0xd079, 0x1db7: 0xd099, 0x1db8: 0x8bdd, 0x1db9: 0xd0b9, 0x1dba: 0xd0d9, 0x1dbb: 0xd0f9,
+	0x1dbc: 0xd119, 0x1dbd: 0xd139, 0x1dbe: 0xd159, 0x1dbf: 0xd179,
+	// Block 0x77, offset 0x1dc0
+	0x1dc0: 0xd199, 0x1dc1: 0xd1b9, 0x1dc2: 0xd1d9, 0x1dc3: 0xd1f9, 0x1dc4: 0xd219, 0x1dc5: 0xd239,
+	0x1dc6: 0xd239, 0x1dc7: 0xd259, 0x1dc8: 0xd279, 0x1dc9: 0xd299, 0x1dca: 0xd2b9, 0x1dcb: 0xd2d9,
+	0x1dcc: 0xd2f9, 0x1dcd: 0xd319, 0x1dce: 0xd339, 0x1dcf: 0xd359, 0x1dd0: 0xd379, 0x1dd1: 0xd399,
+	0x1dd2: 0xd3b9, 0x1dd3: 0xd3d9, 0x1dd4: 0xd3f9, 0x1dd5: 0xd419, 0x1dd6: 0xd439, 0x1dd7: 0xd459,
+	0x1dd8: 0xd479, 0x1dd9: 0x8bfd, 0x1dda: 0xd499, 0x1ddb: 0xd4b9, 0x1ddc: 0xd4d9, 0x1ddd: 0xc309,
+	0x1dde: 0xd4f9, 0x1ddf: 0xd519, 0x1de0: 0x8c1d, 0x1de1: 0x8c3d, 0x1de2: 0xd539, 0x1de3: 0xd559,
+	0x1de4: 0xd579, 0x1de5: 0xd599, 0x1de6: 0xd5b9, 0x1de7: 0xd5d9, 0x1de8: 0x0040, 0x1de9: 0xd5f9,
+	0x1dea: 0xd619, 0x1deb: 0xd619, 0x1dec: 0x8c5d, 0x1ded: 0xd639, 0x1dee: 0xd659, 0x1def: 0xd679,
+	0x1df0: 0xd699, 0x1df1: 0x8c7d, 0x1df2: 0xd6b9, 0x1df3: 0xd6d9, 0x1df4: 0x0040, 0x1df5: 0xd6f9,
+	0x1df6: 0xd719, 0x1df7: 0xd739, 0x1df8: 0xd759, 0x1df9: 0xd779, 0x1dfa: 0xd799, 0x1dfb: 0x8c9d,
+	0x1dfc: 0xd7b9, 0x1dfd: 0x8cbd, 0x1dfe: 0xd7d9, 0x1dff: 0xd7f9,
+	// Block 0x78, offset 0x1e00
+	0x1e00: 0xd819, 0x1e01: 0xd839, 0x1e02: 0xd859, 0x1e03: 0xd879, 0x1e04: 0xd899, 0x1e05: 0xd8b9,
+	0x1e06: 0xd8d9, 0x1e07: 0xd8f9, 0x1e08: 0xd919, 0x1e09: 0x8cdd, 0x1e0a: 0xd939, 0x1e0b: 0xd959,
+	0x1e0c: 0xd979, 0x1e0d: 0xd999, 0x1e0e: 0xd9b9, 0x1e0f: 0x8cfd, 0x1e10: 0xd9d9, 0x1e11: 0x8d1d,
+	0x1e12: 0x8d3d, 0x1e13: 0xd9f9, 0x1e14: 0xda19, 0x1e15: 0xda19, 0x1e16: 0xda39, 0x1e17: 0x8d5d,
+	0x1e18: 0x8d7d, 0x1e19: 0xda59, 0x1e1a: 0xda79, 0x1e1b: 0xda99, 0x1e1c: 0xdab9, 0x1e1d: 0xdad9,
+	0x1e1e: 0xdaf9, 0x1e1f: 0xdb19, 0x1e20: 0xdb39, 0x1e21: 0xdb59, 0x1e22: 0xdb79, 0x1e23: 0xdb99,
+	0x1e24: 0x8d9d, 0x1e25: 0xdbb9, 0x1e26: 0xdbd9, 0x1e27: 0xdbf9, 0x1e28: 0xdc19, 0x1e29: 0xdbf9,
+	0x1e2a: 0xdc39, 0x1e2b: 0xdc59, 0x1e2c: 0xdc79, 0x1e2d: 0xdc99, 0x1e2e: 0xdcb9, 0x1e2f: 0xdcd9,
+	0x1e30: 0xdcf9, 0x1e31: 0xdd19, 0x1e32: 0xdd39, 0x1e33: 0xdd59, 0x1e34: 0xdd79, 0x1e35: 0xdd99,
+	0x1e36: 0xddb9, 0x1e37: 0xddd9, 0x1e38: 0x8dbd, 0x1e39: 0xddf9, 0x1e3a: 0xde19, 0x1e3b: 0xde39,
+	0x1e3c: 0xde59, 0x1e3d: 0xde79, 0x1e3e: 0x8ddd, 0x1e3f: 0xde99,
+	// Block 0x79, offset 0x1e40
+	0x1e40: 0xe599, 0x1e41: 0xe5b9, 0x1e42: 0xe5d9, 0x1e43: 0xe5f9, 0x1e44: 0xe619, 0x1e45: 0xe639,
+	0x1e46: 0x8efd, 0x1e47: 0xe659, 0x1e48: 0xe679, 0x1e49: 0xe699, 0x1e4a: 0xe6b9, 0x1e4b: 0xe6d9,
+	0x1e4c: 0xe6f9, 0x1e4d: 0x8f1d, 0x1e4e: 0xe719, 0x1e4f: 0xe739, 0x1e50: 0x8f3d, 0x1e51: 0x8f5d,
+	0x1e52: 0xe759, 0x1e53: 0xe779, 0x1e54: 0xe799, 0x1e55: 0xe7b9, 0x1e56: 0xe7d9, 0x1e57: 0xe7f9,
+	0x1e58: 0xe819, 0x1e59: 0xe839, 0x1e5a: 0xe859, 0x1e5b: 0x8f7d, 0x1e5c: 0xe879, 0x1e5d: 0x8f9d,
+	0x1e5e: 0xe899, 0x1e5f: 0x0040, 0x1e60: 0xe8b9, 0x1e61: 0xe8d9, 0x1e62: 0xe8f9, 0x1e63: 0x8fbd,
+	0x1e64: 0xe919, 0x1e65: 0xe939, 0x1e66: 0x8fdd, 0x1e67: 0x8ffd, 0x1e68: 0xe959, 0x1e69: 0xe979,
+	0x1e6a: 0xe999, 0x1e6b: 0xe9b9, 0x1e6c: 0xe9d9, 0x1e6d: 0xe9d9, 0x1e6e: 0xe9f9, 0x1e6f: 0xea19,
+	0x1e70: 0xea39, 0x1e71: 0xea59, 0x1e72: 0xea79, 0x1e73: 0xea99, 0x1e74: 0xeab9, 0x1e75: 0x901d,
+	0x1e76: 0xead9, 0x1e77: 0x903d, 0x1e78: 0xeaf9, 0x1e79: 0x905d, 0x1e7a: 0xeb19, 0x1e7b: 0x907d,
+	0x1e7c: 0x909d, 0x1e7d: 0x90bd, 0x1e7e: 0xeb39, 0x1e7f: 0xeb59,
+	// Block 0x7a, offset 0x1e80
+	0x1e80: 0xeb79, 0x1e81: 0x90dd, 0x1e82: 0x90fd, 0x1e83: 0x911d, 0x1e84: 0x913d, 0x1e85: 0xeb99,
+	0x1e86: 0xebb9, 0x1e87: 0xebb9, 0x1e88: 0xebd9, 0x1e89: 0xebf9, 0x1e8a: 0xec19, 0x1e8b: 0xec39,
+	0x1e8c: 0xec59, 0x1e8d: 0x915d, 0x1e8e: 0xec79, 0x1e8f: 0xec99, 0x1e90: 0xecb9, 0x1e91: 0xecd9,
+	0x1e92: 0x917d, 0x1e93: 0xecf9, 0x1e94: 0x919d, 0x1e95: 0x91bd, 0x1e96: 0xed19, 0x1e97: 0xed39,
+	0x1e98: 0xed59, 0x1e99: 0xed79, 0x1e9a: 0xed99, 0x1e9b: 0xedb9, 0x1e9c: 0x91dd, 0x1e9d: 0x91fd,
+	0x1e9e: 0x921d, 0x1e9f: 0x0040, 0x1ea0: 0xedd9, 0x1ea1: 0x923d, 0x1ea2: 0xedf9, 0x1ea3: 0xee19,
+	0x1ea4: 0xee39, 0x1ea5: 0x925d, 0x1ea6: 0xee59, 0x1ea7: 0xee79, 0x1ea8: 0xee99, 0x1ea9: 0xeeb9,
+	0x1eaa: 0xeed9, 0x1eab: 0x927d, 0x1eac: 0xeef9, 0x1ead: 0xef19, 0x1eae: 0xef39, 0x1eaf: 0xef59,
+	0x1eb0: 0xef79, 0x1eb1: 0xef99, 0x1eb2: 0x929d, 0x1eb3: 0x92bd, 0x1eb4: 0xefb9, 0x1eb5: 0x92dd,
+	0x1eb6: 0xefd9, 0x1eb7: 0x92fd, 0x1eb8: 0xeff9, 0x1eb9: 0xf019, 0x1eba: 0xf039, 0x1ebb: 0x931d,
+	0x1ebc: 0x933d, 0x1ebd: 0xf059, 0x1ebe: 0x935d, 0x1ebf: 0xf079,
+	// Block 0x7b, offset 0x1ec0
+	0x1ec0: 0xf6b9, 0x1ec1: 0xf6d9, 0x1ec2: 0xf6f9, 0x1ec3: 0xf719, 0x1ec4: 0xf739, 0x1ec5: 0x951d,
+	0x1ec6: 0xf759, 0x1ec7: 0xf779, 0x1ec8: 0xf799, 0x1ec9: 0xf7b9, 0x1eca: 0xf7d9, 0x1ecb: 0x953d,
+	0x1ecc: 0x955d, 0x1ecd: 0xf7f9, 0x1ece: 0xf819, 0x1ecf: 0xf839, 0x1ed0: 0xf859, 0x1ed1: 0xf879,
+	0x1ed2: 0xf899, 0x1ed3: 0x957d, 0x1ed4: 0xf8b9, 0x1ed5: 0xf8d9, 0x1ed6: 0xf8f9, 0x1ed7: 0xf919,
+	0x1ed8: 0x959d, 0x1ed9: 0x95bd, 0x1eda: 0xf939, 0x1edb: 0xf959, 0x1edc: 0xf979, 0x1edd: 0x95dd,
+	0x1ede: 0xf999, 0x1edf: 0xf9b9, 0x1ee0: 0x6815, 0x1ee1: 0x95fd, 0x1ee2: 0xf9d9, 0x1ee3: 0xf9f9,
+	0x1ee4: 0xfa19, 0x1ee5: 0x961d, 0x1ee6: 0xfa39, 0x1ee7: 0xfa59, 0x1ee8: 0xfa79, 0x1ee9: 0xfa99,
+	0x1eea: 0xfab9, 0x1eeb: 0xfad9, 0x1eec: 0xfaf9, 0x1eed: 0x963d, 0x1eee: 0xfb19, 0x1eef: 0xfb39,
+	0x1ef0: 0xfb59, 0x1ef1: 0x965d, 0x1ef2: 0xfb79, 0x1ef3: 0xfb99, 0x1ef4: 0xfbb9, 0x1ef5: 0xfbd9,
+	0x1ef6: 0x7b35, 0x1ef7: 0x967d, 0x1ef8: 0xfbf9, 0x1ef9: 0xfc19, 0x1efa: 0xfc39, 0x1efb: 0x969d,
+	0x1efc: 0xfc59, 0x1efd: 0x96bd, 0x1efe: 0xfc79, 0x1eff: 0xfc79,
+	// Block 0x7c, offset 0x1f00
+	0x1f00: 0xfc99, 0x1f01: 0x96dd, 0x1f02: 0xfcb9, 0x1f03: 0xfcd9, 0x1f04: 0xfcf9, 0x1f05: 0xfd19,
+	0x1f06: 0xfd39, 0x1f07: 0xfd59, 0x1f08: 0xfd79, 0x1f09: 0x96fd, 0x1f0a: 0xfd99, 0x1f0b: 0xfdb9,
+	0x1f0c: 0xfdd9, 0x1f0d: 0xfdf9, 0x1f0e: 0xfe19, 0x1f0f: 0xfe39, 0x1f10: 0x971d, 0x1f11: 0xfe59,
+	0x1f12: 0x973d, 0x1f13: 0x975d, 0x1f14: 0x977d, 0x1f15: 0xfe79, 0x1f16: 0xfe99, 0x1f17: 0xfeb9,
+	0x1f18: 0xfed9, 0x1f19: 0xfef9, 0x1f1a: 0xff19, 0x1f1b: 0xff39, 0x1f1c: 0xff59, 0x1f1d: 0x979d,
+	0x1f1e: 0x0040, 0x1f1f: 0x0040, 0x1f20: 0x0040, 0x1f21: 0x0040, 0x1f22: 0x0040, 0x1f23: 0x0040,
+	0x1f24: 0x0040, 0x1f25: 0x0040, 0x1f26: 0x0040, 0x1f27: 0x0040, 0x1f28: 0x0040, 0x1f29: 0x0040,
+	0x1f2a: 0x0040, 0x1f2b: 0x0040, 0x1f2c: 0x0040, 0x1f2d: 0x0040, 0x1f2e: 0x0040, 0x1f2f: 0x0040,
+	0x1f30: 0x0040, 0x1f31: 0x0040, 0x1f32: 0x0040, 0x1f33: 0x0040, 0x1f34: 0x0040, 0x1f35: 0x0040,
+	0x1f36: 0x0040, 0x1f37: 0x0040, 0x1f38: 0x0040, 0x1f39: 0x0040, 0x1f3a: 0x0040, 0x1f3b: 0x0040,
+	0x1f3c: 0x0040, 0x1f3d: 0x0040, 0x1f3e: 0x0040, 0x1f3f: 0x0040,
+}
+
+// idnaIndex: 35 blocks, 2240 entries, 4480 bytes
+// Block 0 is the zero block.
+var idnaIndex = [2240]uint16{
+	// Block 0x0, offset 0x0
+	// Block 0x1, offset 0x40
+	// Block 0x2, offset 0x80
+	// Block 0x3, offset 0xc0
+	0xc2: 0x01, 0xc3: 0x7b, 0xc4: 0x02, 0xc5: 0x03, 0xc6: 0x04, 0xc7: 0x05,
+	0xc8: 0x06, 0xc9: 0x7c, 0xca: 0x7d, 0xcb: 0x07, 0xcc: 0x7e, 0xcd: 0x08, 0xce: 0x09, 0xcf: 0x0a,
+	0xd0: 0x7f, 0xd1: 0x0b, 0xd2: 0x0c, 0xd3: 0x0d, 0xd4: 0x0e, 0xd5: 0x80, 0xd6: 0x81, 0xd7: 0x82,
+	0xd8: 0x0f, 0xd9: 0x83, 0xda: 0x84, 0xdb: 0x10, 0xdc: 0x11, 0xdd: 0x85, 0xde: 0x86, 0xdf: 0x87,
+	0xe0: 0x02, 0xe1: 0x03, 0xe2: 0x04, 0xe3: 0x05, 0xe4: 0x06, 0xe5: 0x07, 0xe6: 0x07, 0xe7: 0x07,
+	0xe8: 0x07, 0xe9: 0x08, 0xea: 0x09, 0xeb: 0x07, 0xec: 0x07, 0xed: 0x0a, 0xee: 0x0b, 0xef: 0x0c,
+	0xf0: 0x1c, 0xf1: 0x1d, 0xf2: 0x1d, 0xf3: 0x1f, 0xf4: 0x20,
+	// Block 0x4, offset 0x100
+	0x120: 0x88, 0x121: 0x89, 0x122: 0x8a, 0x123: 0x8b, 0x124: 0x8c, 0x125: 0x12, 0x126: 0x13, 0x127: 0x14,
+	0x128: 0x15, 0x129: 0x16, 0x12a: 0x17, 0x12b: 0x18, 0x12c: 0x19, 0x12d: 0x1a, 0x12e: 0x1b, 0x12f: 0x8d,
+	0x130: 0x8e, 0x131: 0x1c, 0x132: 0x1d, 0x133: 0x1e, 0x134: 0x8f, 0x135: 0x1f, 0x136: 0x90, 0x137: 0x91,
+	0x138: 0x92, 0x139: 0x93, 0x13a: 0x20, 0x13b: 0x94, 0x13c: 0x95, 0x13d: 0x21, 0x13e: 0x22, 0x13f: 0x96,
+	// Block 0x5, offset 0x140
+	0x140: 0x97, 0x141: 0x98, 0x142: 0x99, 0x143: 0x9a, 0x144: 0x9b, 0x145: 0x9c, 0x146: 0x9b, 0x147: 0x9b,
+	0x148: 0x9d, 0x149: 0x9e, 0x14a: 0x9f, 0x14b: 0xa0, 0x14c: 0xa1, 0x14d: 0xa2, 0x14e: 0xa3, 0x14f: 0xa4,
+	0x150: 0xa5, 0x151: 0x9d, 0x152: 0x9d, 0x153: 0x9d, 0x154: 0x9d, 0x155: 0x9d, 0x156: 0x9d, 0x157: 0x9d,
+	0x158: 0x9d, 0x159: 0xa6, 0x15a: 0xa7, 0x15b: 0xa8, 0x15c: 0xa9, 0x15d: 0xaa, 0x15e: 0xab, 0x15f: 0xac,
+	0x160: 0xad, 0x161: 0xae, 0x162: 0xaf, 0x163: 0xb0, 0x164: 0xb1, 0x165: 0xb2, 0x166: 0xb3, 0x167: 0xb4,
+	0x168: 0xb5, 0x169: 0xb6, 0x16a: 0xb7, 0x16b: 0xb8, 0x16c: 0xb9, 0x16d: 0xba, 0x16e: 0xbb, 0x16f: 0xbc,
+	0x170: 0xbd, 0x171: 0xbe, 0x172: 0xbf, 0x173: 0xc0, 0x174: 0x23, 0x175: 0x24, 0x176: 0x25, 0x177: 0xc1,
+	0x178: 0x26, 0x179: 0x26, 0x17a: 0x27, 0x17b: 0x26, 0x17c: 0xc2, 0x17d: 0x28, 0x17e: 0x29, 0x17f: 0x2a,
+	// Block 0x6, offset 0x180
+	0x180: 0x2b, 0x181: 0x2c, 0x182: 0x2d, 0x183: 0xc3, 0x184: 0x2e, 0x185: 0x2f, 0x186: 0xc4, 0x187: 0x9b,
+	0x188: 0xc5, 0x189: 0xc6, 0x18a: 0x9b, 0x18b: 0x9b, 0x18c: 0xc7, 0x18d: 0x9b, 0x18e: 0x9b, 0x18f: 0xc8,
+	0x190: 0xc9, 0x191: 0x30, 0x192: 0x31, 0x193: 0x32, 0x194: 0x9b, 0x195: 0x9b, 0x196: 0x9b, 0x197: 0x9b,
+	0x198: 0x9b, 0x199: 0x9b, 0x19a: 0x9b, 0x19b: 0x9b, 0x19c: 0x9b, 0x19d: 0x9b, 0x19e: 0x9b, 0x19f: 0x9b,
+	0x1a0: 0x9b, 0x1a1: 0x9b, 0x1a2: 0x9b, 0x1a3: 0x9b, 0x1a4: 0x9b, 0x1a5: 0x9b, 0x1a6: 0x9b, 0x1a7: 0x9b,
+	0x1a8: 0xca, 0x1a9: 0xcb, 0x1aa: 0x9b, 0x1ab: 0xcc, 0x1ac: 0x9b, 0x1ad: 0xcd, 0x1ae: 0xce, 0x1af: 0xcf,
+	0x1b0: 0xd0, 0x1b1: 0x33, 0x1b2: 0x26, 0x1b3: 0x34, 0x1b4: 0xd1, 0x1b5: 0xd2, 0x1b6: 0xd3, 0x1b7: 0xd4,
+	0x1b8: 0xd5, 0x1b9: 0xd6, 0x1ba: 0xd7, 0x1bb: 0xd8, 0x1bc: 0xd9, 0x1bd: 0xda, 0x1be: 0xdb, 0x1bf: 0x35,
+	// Block 0x7, offset 0x1c0
+	0x1c0: 0x36, 0x1c1: 0xdc, 0x1c2: 0xdd, 0x1c3: 0xde, 0x1c4: 0xdf, 0x1c5: 0x37, 0x1c6: 0x38, 0x1c7: 0xe0,
+	0x1c8: 0xe1, 0x1c9: 0x39, 0x1ca: 0x3a, 0x1cb: 0x3b, 0x1cc: 0x3c, 0x1cd: 0x3d, 0x1ce: 0x3e, 0x1cf: 0x3f,
+	0x1d0: 0x9d, 0x1d1: 0x9d, 0x1d2: 0x9d, 0x1d3: 0x9d, 0x1d4: 0x9d, 0x1d5: 0x9d, 0x1d6: 0x9d, 0x1d7: 0x9d,
+	0x1d8: 0x9d, 0x1d9: 0x9d, 0x1da: 0x9d, 0x1db: 0x9d, 0x1dc: 0x9d, 0x1dd: 0x9d, 0x1de: 0x9d, 0x1df: 0x9d,
+	0x1e0: 0x9d, 0x1e1: 0x9d, 0x1e2: 0x9d, 0x1e3: 0x9d, 0x1e4: 0x9d, 0x1e5: 0x9d, 0x1e6: 0x9d, 0x1e7: 0x9d,
+	0x1e8: 0x9d, 0x1e9: 0x9d, 0x1ea: 0x9d, 0x1eb: 0x9d, 0x1ec: 0x9d, 0x1ed: 0x9d, 0x1ee: 0x9d, 0x1ef: 0x9d,
+	0x1f0: 0x9d, 0x1f1: 0x9d, 0x1f2: 0x9d, 0x1f3: 0x9d, 0x1f4: 0x9d, 0x1f5: 0x9d, 0x1f6: 0x9d, 0x1f7: 0x9d,
+	0x1f8: 0x9d, 0x1f9: 0x9d, 0x1fa: 0x9d, 0x1fb: 0x9d, 0x1fc: 0x9d, 0x1fd: 0x9d, 0x1fe: 0x9d, 0x1ff: 0x9d,
+	// Block 0x8, offset 0x200
+	0x200: 0x9d, 0x201: 0x9d, 0x202: 0x9d, 0x203: 0x9d, 0x204: 0x9d, 0x205: 0x9d, 0x206: 0x9d, 0x207: 0x9d,
+	0x208: 0x9d, 0x209: 0x9d, 0x20a: 0x9d, 0x20b: 0x9d, 0x20c: 0x9d, 0x20d: 0x9d, 0x20e: 0x9d, 0x20f: 0x9d,
+	0x210: 0x9d, 0x211: 0x9d, 0x212: 0x9d, 0x213: 0x9d, 0x214: 0x9d, 0x215: 0x9d, 0x216: 0x9d, 0x217: 0x9d,
+	0x218: 0x9d, 0x219: 0x9d, 0x21a: 0x9d, 0x21b: 0x9d, 0x21c: 0x9d, 0x21d: 0x9d, 0x21e: 0x9d, 0x21f: 0x9d,
+	0x220: 0x9d, 0x221: 0x9d, 0x222: 0x9d, 0x223: 0x9d, 0x224: 0x9d, 0x225: 0x9d, 0x226: 0x9d, 0x227: 0x9d,
+	0x228: 0x9d, 0x229: 0x9d, 0x22a: 0x9d, 0x22b: 0x9d, 0x22c: 0x9d, 0x22d: 0x9d, 0x22e: 0x9d, 0x22f: 0x9d,
+	0x230: 0x9d, 0x231: 0x9d, 0x232: 0x9d, 0x233: 0x9d, 0x234: 0x9d, 0x235: 0x9d, 0x236: 0xb0, 0x237: 0x9b,
+	0x238: 0x9d, 0x239: 0x9d, 0x23a: 0x9d, 0x23b: 0x9d, 0x23c: 0x9d, 0x23d: 0x9d, 0x23e: 0x9d, 0x23f: 0x9d,
+	// Block 0x9, offset 0x240
+	0x240: 0x9d, 0x241: 0x9d, 0x242: 0x9d, 0x243: 0x9d, 0x244: 0x9d, 0x245: 0x9d, 0x246: 0x9d, 0x247: 0x9d,
+	0x248: 0x9d, 0x249: 0x9d, 0x24a: 0x9d, 0x24b: 0x9d, 0x24c: 0x9d, 0x24d: 0x9d, 0x24e: 0x9d, 0x24f: 0x9d,
+	0x250: 0x9d, 0x251: 0x9d, 0x252: 0x9d, 0x253: 0x9d, 0x254: 0x9d, 0x255: 0x9d, 0x256: 0x9d, 0x257: 0x9d,
+	0x258: 0x9d, 0x259: 0x9d, 0x25a: 0x9d, 0x25b: 0x9d, 0x25c: 0x9d, 0x25d: 0x9d, 0x25e: 0x9d, 0x25f: 0x9d,
+	0x260: 0x9d, 0x261: 0x9d, 0x262: 0x9d, 0x263: 0x9d, 0x264: 0x9d, 0x265: 0x9d, 0x266: 0x9d, 0x267: 0x9d,
+	0x268: 0x9d, 0x269: 0x9d, 0x26a: 0x9d, 0x26b: 0x9d, 0x26c: 0x9d, 0x26d: 0x9d, 0x26e: 0x9d, 0x26f: 0x9d,
+	0x270: 0x9d, 0x271: 0x9d, 0x272: 0x9d, 0x273: 0x9d, 0x274: 0x9d, 0x275: 0x9d, 0x276: 0x9d, 0x277: 0x9d,
+	0x278: 0x9d, 0x279: 0x9d, 0x27a: 0x9d, 0x27b: 0x9d, 0x27c: 0x9d, 0x27d: 0x9d, 0x27e: 0x9d, 0x27f: 0x9d,
+	// Block 0xa, offset 0x280
+	0x280: 0x9d, 0x281: 0x9d, 0x282: 0x9d, 0x283: 0x9d, 0x284: 0x9d, 0x285: 0x9d, 0x286: 0x9d, 0x287: 0x9d,
+	0x288: 0x9d, 0x289: 0x9d, 0x28a: 0x9d, 0x28b: 0x9d, 0x28c: 0x9d, 0x28d: 0x9d, 0x28e: 0x9d, 0x28f: 0x9d,
+	0x290: 0x9d, 0x291: 0x9d, 0x292: 0x9d, 0x293: 0x9d, 0x294: 0x9d, 0x295: 0x9d, 0x296: 0x9d, 0x297: 0x9d,
+	0x298: 0x9d, 0x299: 0x9d, 0x29a: 0x9d, 0x29b: 0x9d, 0x29c: 0x9d, 0x29d: 0x9d, 0x29e: 0x9d, 0x29f: 0x9d,
+	0x2a0: 0x9d, 0x2a1: 0x9d, 0x2a2: 0x9d, 0x2a3: 0x9d, 0x2a4: 0x9d, 0x2a5: 0x9d, 0x2a6: 0x9d, 0x2a7: 0x9d,
+	0x2a8: 0x9d, 0x2a9: 0x9d, 0x2aa: 0x9d, 0x2ab: 0x9d, 0x2ac: 0x9d, 0x2ad: 0x9d, 0x2ae: 0x9d, 0x2af: 0x9d,
+	0x2b0: 0x9d, 0x2b1: 0x9d, 0x2b2: 0x9d, 0x2b3: 0x9d, 0x2b4: 0x9d, 0x2b5: 0x9d, 0x2b6: 0x9d, 0x2b7: 0x9d,
+	0x2b8: 0x9d, 0x2b9: 0x9d, 0x2ba: 0x9d, 0x2bb: 0x9d, 0x2bc: 0x9d, 0x2bd: 0x9d, 0x2be: 0x9d, 0x2bf: 0xe2,
+	// Block 0xb, offset 0x2c0
+	0x2c0: 0x9d, 0x2c1: 0x9d, 0x2c2: 0x9d, 0x2c3: 0x9d, 0x2c4: 0x9d, 0x2c5: 0x9d, 0x2c6: 0x9d, 0x2c7: 0x9d,
+	0x2c8: 0x9d, 0x2c9: 0x9d, 0x2ca: 0x9d, 0x2cb: 0x9d, 0x2cc: 0x9d, 0x2cd: 0x9d, 0x2ce: 0x9d, 0x2cf: 0x9d,
+	0x2d0: 0x9d, 0x2d1: 0x9d, 0x2d2: 0xe3, 0x2d3: 0xe4, 0x2d4: 0x9d, 0x2d5: 0x9d, 0x2d6: 0x9d, 0x2d7: 0x9d,
+	0x2d8: 0xe5, 0x2d9: 0x40, 0x2da: 0x41, 0x2db: 0xe6, 0x2dc: 0x42, 0x2dd: 0x43, 0x2de: 0x44, 0x2df: 0xe7,
+	0x2e0: 0xe8, 0x2e1: 0xe9, 0x2e2: 0xea, 0x2e3: 0xeb, 0x2e4: 0xec, 0x2e5: 0xed, 0x2e6: 0xee, 0x2e7: 0xef,
+	0x2e8: 0xf0, 0x2e9: 0xf1, 0x2ea: 0xf2, 0x2eb: 0xf3, 0x2ec: 0xf4, 0x2ed: 0xf5, 0x2ee: 0xf6, 0x2ef: 0xf7,
+	0x2f0: 0x9d, 0x2f1: 0x9d, 0x2f2: 0x9d, 0x2f3: 0x9d, 0x2f4: 0x9d, 0x2f5: 0x9d, 0x2f6: 0x9d, 0x2f7: 0x9d,
+	0x2f8: 0x9d, 0x2f9: 0x9d, 0x2fa: 0x9d, 0x2fb: 0x9d, 0x2fc: 0x9d, 0x2fd: 0x9d, 0x2fe: 0x9d, 0x2ff: 0x9d,
+	// Block 0xc, offset 0x300
+	0x300: 0x9d, 0x301: 0x9d, 0x302: 0x9d, 0x303: 0x9d, 0x304: 0x9d, 0x305: 0x9d, 0x306: 0x9d, 0x307: 0x9d,
+	0x308: 0x9d, 0x309: 0x9d, 0x30a: 0x9d, 0x30b: 0x9d, 0x30c: 0x9d, 0x30d: 0x9d, 0x30e: 0x9d, 0x30f: 0x9d,
+	0x310: 0x9d, 0x311: 0x9d, 0x312: 0x9d, 0x313: 0x9d, 0x314: 0x9d, 0x315: 0x9d, 0x316: 0x9d, 0x317: 0x9d,
+	0x318: 0x9d, 0x319: 0x9d, 0x31a: 0x9d, 0x31b: 0x9d, 0x31c: 0x9d, 0x31d: 0x9d, 0x31e: 0xf8, 0x31f: 0xf9,
+	// Block 0xd, offset 0x340
+	0x340: 0xb8, 0x341: 0xb8, 0x342: 0xb8, 0x343: 0xb8, 0x344: 0xb8, 0x345: 0xb8, 0x346: 0xb8, 0x347: 0xb8,
+	0x348: 0xb8, 0x349: 0xb8, 0x34a: 0xb8, 0x34b: 0xb8, 0x34c: 0xb8, 0x34d: 0xb8, 0x34e: 0xb8, 0x34f: 0xb8,
+	0x350: 0xb8, 0x351: 0xb8, 0x352: 0xb8, 0x353: 0xb8, 0x354: 0xb8, 0x355: 0xb8, 0x356: 0xb8, 0x357: 0xb8,
+	0x358: 0xb8, 0x359: 0xb8, 0x35a: 0xb8, 0x35b: 0xb8, 0x35c: 0xb8, 0x35d: 0xb8, 0x35e: 0xb8, 0x35f: 0xb8,
+	0x360: 0xb8, 0x361: 0xb8, 0x362: 0xb8, 0x363: 0xb8, 0x364: 0xb8, 0x365: 0xb8, 0x366: 0xb8, 0x367: 0xb8,
+	0x368: 0xb8, 0x369: 0xb8, 0x36a: 0xb8, 0x36b: 0xb8, 0x36c: 0xb8, 0x36d: 0xb8, 0x36e: 0xb8, 0x36f: 0xb8,
+	0x370: 0xb8, 0x371: 0xb8, 0x372: 0xb8, 0x373: 0xb8, 0x374: 0xb8, 0x375: 0xb8, 0x376: 0xb8, 0x377: 0xb8,
+	0x378: 0xb8, 0x379: 0xb8, 0x37a: 0xb8, 0x37b: 0xb8, 0x37c: 0xb8, 0x37d: 0xb8, 0x37e: 0xb8, 0x37f: 0xb8,
+	// Block 0xe, offset 0x380
+	0x380: 0xb8, 0x381: 0xb8, 0x382: 0xb8, 0x383: 0xb8, 0x384: 0xb8, 0x385: 0xb8, 0x386: 0xb8, 0x387: 0xb8,
+	0x388: 0xb8, 0x389: 0xb8, 0x38a: 0xb8, 0x38b: 0xb8, 0x38c: 0xb8, 0x38d: 0xb8, 0x38e: 0xb8, 0x38f: 0xb8,
+	0x390: 0xb8, 0x391: 0xb8, 0x392: 0xb8, 0x393: 0xb8, 0x394: 0xb8, 0x395: 0xb8, 0x396: 0xb8, 0x397: 0xb8,
+	0x398: 0xb8, 0x399: 0xb8, 0x39a: 0xb8, 0x39b: 0xb8, 0x39c: 0xb8, 0x39d: 0xb8, 0x39e: 0xb8, 0x39f: 0xb8,
+	0x3a0: 0xb8, 0x3a1: 0xb8, 0x3a2: 0xb8, 0x3a3: 0xb8, 0x3a4: 0xfa, 0x3a5: 0xfb, 0x3a6: 0xfc, 0x3a7: 0xfd,
+	0x3a8: 0x45, 0x3a9: 0xfe, 0x3aa: 0xff, 0x3ab: 0x46, 0x3ac: 0x47, 0x3ad: 0x48, 0x3ae: 0x49, 0x3af: 0x4a,
+	0x3b0: 0x100, 0x3b1: 0x4b, 0x3b2: 0x4c, 0x3b3: 0x4d, 0x3b4: 0x4e, 0x3b5: 0x4f, 0x3b6: 0x101, 0x3b7: 0x50,
+	0x3b8: 0x51, 0x3b9: 0x52, 0x3ba: 0x53, 0x3bb: 0x54, 0x3bc: 0x55, 0x3bd: 0x56, 0x3be: 0x57, 0x3bf: 0x58,
+	// Block 0xf, offset 0x3c0
+	0x3c0: 0x102, 0x3c1: 0x103, 0x3c2: 0x9d, 0x3c3: 0x104, 0x3c4: 0x105, 0x3c5: 0x9b, 0x3c6: 0x106, 0x3c7: 0x107,
+	0x3c8: 0xb8, 0x3c9: 0xb8, 0x3ca: 0x108, 0x3cb: 0x109, 0x3cc: 0x10a, 0x3cd: 0x10b, 0x3ce: 0x10c, 0x3cf: 0x10d,
+	0x3d0: 0x10e, 0x3d1: 0x9d, 0x3d2: 0x10f, 0x3d3: 0x110, 0x3d4: 0x111, 0x3d5: 0x112, 0x3d6: 0xb8, 0x3d7: 0xb8,
+	0x3d8: 0x9d, 0x3d9: 0x9d, 0x3da: 0x9d, 0x3db: 0x9d, 0x3dc: 0x113, 0x3dd: 0x114, 0x3de: 0xb8, 0x3df: 0xb8,
+	0x3e0: 0x115, 0x3e1: 0x116, 0x3e2: 0x117, 0x3e3: 0x118, 0x3e4: 0x119, 0x3e5: 0xb8, 0x3e6: 0x11a, 0x3e7: 0x11b,
+	0x3e8: 0x11c, 0x3e9: 0x11d, 0x3ea: 0x11e, 0x3eb: 0x59, 0x3ec: 0x11f, 0x3ed: 0x120, 0x3ee: 0x5a, 0x3ef: 0xb8,
+	0x3f0: 0x9d, 0x3f1: 0x121, 0x3f2: 0x122, 0x3f3: 0x123, 0x3f4: 0xb8, 0x3f5: 0xb8, 0x3f6: 0xb8, 0x3f7: 0xb8,
+	0x3f8: 0xb8, 0x3f9: 0x124, 0x3fa: 0xb8, 0x3fb: 0xb8, 0x3fc: 0xb8, 0x3fd: 0xb8, 0x3fe: 0xb8, 0x3ff: 0xb8,
+	// Block 0x10, offset 0x400
+	0x400: 0x125, 0x401: 0x126, 0x402: 0x127, 0x403: 0x128, 0x404: 0x129, 0x405: 0x12a, 0x406: 0x12b, 0x407: 0x12c,
+	0x408: 0x12d, 0x409: 0xb8, 0x40a: 0x12e, 0x40b: 0x12f, 0x40c: 0x5b, 0x40d: 0x5c, 0x40e: 0xb8, 0x40f: 0xb8,
+	0x410: 0x130, 0x411: 0x131, 0x412: 0x132, 0x413: 0x133, 0x414: 0xb8, 0x415: 0xb8, 0x416: 0x134, 0x417: 0x135,
+	0x418: 0x136, 0x419: 0x137, 0x41a: 0x138, 0x41b: 0x139, 0x41c: 0x13a, 0x41d: 0xb8, 0x41e: 0xb8, 0x41f: 0xb8,
+	0x420: 0xb8, 0x421: 0xb8, 0x422: 0x13b, 0x423: 0x13c, 0x424: 0xb8, 0x425: 0xb8, 0x426: 0xb8, 0x427: 0xb8,
+	0x428: 0xb8, 0x429: 0xb8, 0x42a: 0xb8, 0x42b: 0x13d, 0x42c: 0xb8, 0x42d: 0xb8, 0x42e: 0xb8, 0x42f: 0xb8,
+	0x430: 0x13e, 0x431: 0x13f, 0x432: 0x140, 0x433: 0xb8, 0x434: 0xb8, 0x435: 0xb8, 0x436: 0xb8, 0x437: 0xb8,
+	0x438: 0xb8, 0x439: 0xb8, 0x43a: 0xb8, 0x43b: 0xb8, 0x43c: 0xb8, 0x43d: 0xb8, 0x43e: 0xb8, 0x43f: 0xb8,
+	// Block 0x11, offset 0x440
+	0x440: 0x9d, 0x441: 0x9d, 0x442: 0x9d, 0x443: 0x9d, 0x444: 0x9d, 0x445: 0x9d, 0x446: 0x9d, 0x447: 0x9d,
+	0x448: 0x9d, 0x449: 0x9d, 0x44a: 0x9d, 0x44b: 0x9d, 0x44c: 0x9d, 0x44d: 0x9d, 0x44e: 0x141, 0x44f: 0xb8,
+	0x450: 0x9b, 0x451: 0x142, 0x452: 0x9d, 0x453: 0x9d, 0x454: 0x9d, 0x455: 0x143, 0x456: 0xb8, 0x457: 0xb8,
+	0x458: 0xb8, 0x459: 0xb8, 0x45a: 0xb8, 0x45b: 0xb8, 0x45c: 0xb8, 0x45d: 0xb8, 0x45e: 0xb8, 0x45f: 0xb8,
+	0x460: 0xb8, 0x461: 0xb8, 0x462: 0xb8, 0x463: 0xb8, 0x464: 0xb8, 0x465: 0xb8, 0x466: 0xb8, 0x467: 0xb8,
+	0x468: 0xb8, 0x469: 0xb8, 0x46a: 0xb8, 0x46b: 0xb8, 0x46c: 0xb8, 0x46d: 0xb8, 0x46e: 0xb8, 0x46f: 0xb8,
+	0x470: 0xb8, 0x471: 0xb8, 0x472: 0xb8, 0x473: 0xb8, 0x474: 0xb8, 0x475: 0xb8, 0x476: 0xb8, 0x477: 0xb8,
+	0x478: 0xb8, 0x479: 0xb8, 0x47a: 0xb8, 0x47b: 0xb8, 0x47c: 0xb8, 0x47d: 0xb8, 0x47e: 0xb8, 0x47f: 0xb8,
+	// Block 0x12, offset 0x480
+	0x480: 0x9d, 0x481: 0x9d, 0x482: 0x9d, 0x483: 0x9d, 0x484: 0x9d, 0x485: 0x9d, 0x486: 0x9d, 0x487: 0x9d,
+	0x488: 0x9d, 0x489: 0x9d, 0x48a: 0x9d, 0x48b: 0x9d, 0x48c: 0x9d, 0x48d: 0x9d, 0x48e: 0x9d, 0x48f: 0x9d,
+	0x490: 0x144, 0x491: 0xb8, 0x492: 0xb8, 0x493: 0xb8, 0x494: 0xb8, 0x495: 0xb8, 0x496: 0xb8, 0x497: 0xb8,
+	0x498: 0xb8, 0x499: 0xb8, 0x49a: 0xb8, 0x49b: 0xb8, 0x49c: 0xb8, 0x49d: 0xb8, 0x49e: 0xb8, 0x49f: 0xb8,
+	0x4a0: 0xb8, 0x4a1: 0xb8, 0x4a2: 0xb8, 0x4a3: 0xb8, 0x4a4: 0xb8, 0x4a5: 0xb8, 0x4a6: 0xb8, 0x4a7: 0xb8,
+	0x4a8: 0xb8, 0x4a9: 0xb8, 0x4aa: 0xb8, 0x4ab: 0xb8, 0x4ac: 0xb8, 0x4ad: 0xb8, 0x4ae: 0xb8, 0x4af: 0xb8,
+	0x4b0: 0xb8, 0x4b1: 0xb8, 0x4b2: 0xb8, 0x4b3: 0xb8, 0x4b4: 0xb8, 0x4b5: 0xb8, 0x4b6: 0xb8, 0x4b7: 0xb8,
+	0x4b8: 0xb8, 0x4b9: 0xb8, 0x4ba: 0xb8, 0x4bb: 0xb8, 0x4bc: 0xb8, 0x4bd: 0xb8, 0x4be: 0xb8, 0x4bf: 0xb8,
+	// Block 0x13, offset 0x4c0
+	0x4c0: 0xb8, 0x4c1: 0xb8, 0x4c2: 0xb8, 0x4c3: 0xb8, 0x4c4: 0xb8, 0x4c5: 0xb8, 0x4c6: 0xb8, 0x4c7: 0xb8,
+	0x4c8: 0xb8, 0x4c9: 0xb8, 0x4ca: 0xb8, 0x4cb: 0xb8, 0x4cc: 0xb8, 0x4cd: 0xb8, 0x4ce: 0xb8, 0x4cf: 0xb8,
+	0x4d0: 0x9d, 0x4d1: 0x9d, 0x4d2: 0x9d, 0x4d3: 0x9d, 0x4d4: 0x9d, 0x4d5: 0x9d, 0x4d6: 0x9d, 0x4d7: 0x9d,
+	0x4d8: 0x9d, 0x4d9: 0x145, 0x4da: 0xb8, 0x4db: 0xb8, 0x4dc: 0xb8, 0x4dd: 0xb8, 0x4de: 0xb8, 0x4df: 0xb8,
+	0x4e0: 0xb8, 0x4e1: 0xb8, 0x4e2: 0xb8, 0x4e3: 0xb8, 0x4e4: 0xb8, 0x4e5: 0xb8, 0x4e6: 0xb8, 0x4e7: 0xb8,
+	0x4e8: 0xb8, 0x4e9: 0xb8, 0x4ea: 0xb8, 0x4eb: 0xb8, 0x4ec: 0xb8, 0x4ed: 0xb8, 0x4ee: 0xb8, 0x4ef: 0xb8,
+	0x4f0: 0xb8, 0x4f1: 0xb8, 0x4f2: 0xb8, 0x4f3: 0xb8, 0x4f4: 0xb8, 0x4f5: 0xb8, 0x4f6: 0xb8, 0x4f7: 0xb8,
+	0x4f8: 0xb8, 0x4f9: 0xb8, 0x4fa: 0xb8, 0x4fb: 0xb8, 0x4fc: 0xb8, 0x4fd: 0xb8, 0x4fe: 0xb8, 0x4ff: 0xb8,
+	// Block 0x14, offset 0x500
+	0x500: 0xb8, 0x501: 0xb8, 0x502: 0xb8, 0x503: 0xb8, 0x504: 0xb8, 0x505: 0xb8, 0x506: 0xb8, 0x507: 0xb8,
+	0x508: 0xb8, 0x509: 0xb8, 0x50a: 0xb8, 0x50b: 0xb8, 0x50c: 0xb8, 0x50d: 0xb8, 0x50e: 0xb8, 0x50f: 0xb8,
+	0x510: 0xb8, 0x511: 0xb8, 0x512: 0xb8, 0x513: 0xb8, 0x514: 0xb8, 0x515: 0xb8, 0x516: 0xb8, 0x517: 0xb8,
+	0x518: 0xb8, 0x519: 0xb8, 0x51a: 0xb8, 0x51b: 0xb8, 0x51c: 0xb8, 0x51d: 0xb8, 0x51e: 0xb8, 0x51f: 0xb8,
+	0x520: 0x9d, 0x521: 0x9d, 0x522: 0x9d, 0x523: 0x9d, 0x524: 0x9d, 0x525: 0x9d, 0x526: 0x9d, 0x527: 0x9d,
+	0x528: 0x13d, 0x529: 0x146, 0x52a: 0xb8, 0x52b: 0x147, 0x52c: 0x148, 0x52d: 0x149, 0x52e: 0x14a, 0x52f: 0xb8,
+	0x530: 0xb8, 0x531: 0xb8, 0x532: 0xb8, 0x533: 0xb8, 0x534: 0xb8, 0x535: 0xb8, 0x536: 0xb8, 0x537: 0xb8,
+	0x538: 0xb8, 0x539: 0xb8, 0x53a: 0xb8, 0x53b: 0xb8, 0x53c: 0x9d, 0x53d: 0x14b, 0x53e: 0x14c, 0x53f: 0x14d,
+	// Block 0x15, offset 0x540
+	0x540: 0x9d, 0x541: 0x9d, 0x542: 0x9d, 0x543: 0x9d, 0x544: 0x9d, 0x545: 0x9d, 0x546: 0x9d, 0x547: 0x9d,
+	0x548: 0x9d, 0x549: 0x9d, 0x54a: 0x9d, 0x54b: 0x9d, 0x54c: 0x9d, 0x54d: 0x9d, 0x54e: 0x9d, 0x54f: 0x9d,
+	0x550: 0x9d, 0x551: 0x9d, 0x552: 0x9d, 0x553: 0x9d, 0x554: 0x9d, 0x555: 0x9d, 0x556: 0x9d, 0x557: 0x9d,
+	0x558: 0x9d, 0x559: 0x9d, 0x55a: 0x9d, 0x55b: 0x9d, 0x55c: 0x9d, 0x55d: 0x9d, 0x55e: 0x9d, 0x55f: 0x14e,
+	0x560: 0x9d, 0x561: 0x9d, 0x562: 0x9d, 0x563: 0x9d, 0x564: 0x9d, 0x565: 0x9d, 0x566: 0x9d, 0x567: 0x9d,
+	0x568: 0x9d, 0x569: 0x9d, 0x56a: 0x9d, 0x56b: 0x14f, 0x56c: 0xb8, 0x56d: 0xb8, 0x56e: 0xb8, 0x56f: 0xb8,
+	0x570: 0xb8, 0x571: 0xb8, 0x572: 0xb8, 0x573: 0xb8, 0x574: 0xb8, 0x575: 0xb8, 0x576: 0xb8, 0x577: 0xb8,
+	0x578: 0xb8, 0x579: 0xb8, 0x57a: 0xb8, 0x57b: 0xb8, 0x57c: 0xb8, 0x57d: 0xb8, 0x57e: 0xb8, 0x57f: 0xb8,
+	// Block 0x16, offset 0x580
+	0x580: 0x150, 0x581: 0xb8, 0x582: 0xb8, 0x583: 0xb8, 0x584: 0xb8, 0x585: 0xb8, 0x586: 0xb8, 0x587: 0xb8,
+	0x588: 0xb8, 0x589: 0xb8, 0x58a: 0xb8, 0x58b: 0xb8, 0x58c: 0xb8, 0x58d: 0xb8, 0x58e: 0xb8, 0x58f: 0xb8,
+	0x590: 0xb8, 0x591: 0xb8, 0x592: 0xb8, 0x593: 0xb8, 0x594: 0xb8, 0x595: 0xb8, 0x596: 0xb8, 0x597: 0xb8,
+	0x598: 0xb8, 0x599: 0xb8, 0x59a: 0xb8, 0x59b: 0xb8, 0x59c: 0xb8, 0x59d: 0xb8, 0x59e: 0xb8, 0x59f: 0xb8,
+	0x5a0: 0xb8, 0x5a1: 0xb8, 0x5a2: 0xb8, 0x5a3: 0xb8, 0x5a4: 0xb8, 0x5a5: 0xb8, 0x5a6: 0xb8, 0x5a7: 0xb8,
+	0x5a8: 0xb8, 0x5a9: 0xb8, 0x5aa: 0xb8, 0x5ab: 0xb8, 0x5ac: 0xb8, 0x5ad: 0xb8, 0x5ae: 0xb8, 0x5af: 0xb8,
+	0x5b0: 0x9d, 0x5b1: 0x151, 0x5b2: 0x152, 0x5b3: 0xb8, 0x5b4: 0xb8, 0x5b5: 0xb8, 0x5b6: 0xb8, 0x5b7: 0xb8,
+	0x5b8: 0xb8, 0x5b9: 0xb8, 0x5ba: 0xb8, 0x5bb: 0xb8, 0x5bc: 0xb8, 0x5bd: 0xb8, 0x5be: 0xb8, 0x5bf: 0xb8,
+	// Block 0x17, offset 0x5c0
+	0x5c0: 0x9b, 0x5c1: 0x9b, 0x5c2: 0x9b, 0x5c3: 0x153, 0x5c4: 0x154, 0x5c5: 0x155, 0x5c6: 0x156, 0x5c7: 0x157,
+	0x5c8: 0x9b, 0x5c9: 0x158, 0x5ca: 0xb8, 0x5cb: 0xb8, 0x5cc: 0x9b, 0x5cd: 0x159, 0x5ce: 0xb8, 0x5cf: 0xb8,
+	0x5d0: 0x5d, 0x5d1: 0x5e, 0x5d2: 0x5f, 0x5d3: 0x60, 0x5d4: 0x61, 0x5d5: 0x62, 0x5d6: 0x63, 0x5d7: 0x64,
+	0x5d8: 0x65, 0x5d9: 0x66, 0x5da: 0x67, 0x5db: 0x68, 0x5dc: 0x69, 0x5dd: 0x6a, 0x5de: 0x6b, 0x5df: 0x6c,
+	0x5e0: 0x9b, 0x5e1: 0x9b, 0x5e2: 0x9b, 0x5e3: 0x9b, 0x5e4: 0x9b, 0x5e5: 0x9b, 0x5e6: 0x9b, 0x5e7: 0x9b,
+	0x5e8: 0x15a, 0x5e9: 0x15b, 0x5ea: 0x15c, 0x5eb: 0xb8, 0x5ec: 0xb8, 0x5ed: 0xb8, 0x5ee: 0xb8, 0x5ef: 0xb8,
+	0x5f0: 0xb8, 0x5f1: 0xb8, 0x5f2: 0xb8, 0x5f3: 0xb8, 0x5f4: 0xb8, 0x5f5: 0xb8, 0x5f6: 0xb8, 0x5f7: 0xb8,
+	0x5f8: 0xb8, 0x5f9: 0xb8, 0x5fa: 0xb8, 0x5fb: 0xb8, 0x5fc: 0xb8, 0x5fd: 0xb8, 0x5fe: 0xb8, 0x5ff: 0xb8,
+	// Block 0x18, offset 0x600
+	0x600: 0x15d, 0x601: 0xb8, 0x602: 0xb8, 0x603: 0xb8, 0x604: 0xb8, 0x605: 0xb8, 0x606: 0xb8, 0x607: 0xb8,
+	0x608: 0xb8, 0x609: 0xb8, 0x60a: 0xb8, 0x60b: 0xb8, 0x60c: 0xb8, 0x60d: 0xb8, 0x60e: 0xb8, 0x60f: 0xb8,
+	0x610: 0xb8, 0x611: 0xb8, 0x612: 0xb8, 0x613: 0xb8, 0x614: 0xb8, 0x615: 0xb8, 0x616: 0xb8, 0x617: 0xb8,
+	0x618: 0xb8, 0x619: 0xb8, 0x61a: 0xb8, 0x61b: 0xb8, 0x61c: 0xb8, 0x61d: 0xb8, 0x61e: 0xb8, 0x61f: 0xb8,
+	0x620: 0x9d, 0x621: 0x9d, 0x622: 0x9d, 0x623: 0x15e, 0x624: 0x6d, 0x625: 0x15f, 0x626: 0xb8, 0x627: 0xb8,
+	0x628: 0xb8, 0x629: 0xb8, 0x62a: 0xb8, 0x62b: 0xb8, 0x62c: 0xb8, 0x62d: 0xb8, 0x62e: 0xb8, 0x62f: 0xb8,
+	0x630: 0xb8, 0x631: 0xb8, 0x632: 0xb8, 0x633: 0xb8, 0x634: 0xb8, 0x635: 0xb8, 0x636: 0xb8, 0x637: 0xb8,
+	0x638: 0x6e, 0x639: 0x6f, 0x63a: 0x70, 0x63b: 0x160, 0x63c: 0xb8, 0x63d: 0xb8, 0x63e: 0xb8, 0x63f: 0xb8,
+	// Block 0x19, offset 0x640
+	0x640: 0x161, 0x641: 0x9b, 0x642: 0x162, 0x643: 0x163, 0x644: 0x71, 0x645: 0x72, 0x646: 0x164, 0x647: 0x165,
+	0x648: 0x73, 0x649: 0x166, 0x64a: 0xb8, 0x64b: 0xb8, 0x64c: 0x9b, 0x64d: 0x9b, 0x64e: 0x9b, 0x64f: 0x9b,
+	0x650: 0x9b, 0x651: 0x9b, 0x652: 0x9b, 0x653: 0x9b, 0x654: 0x9b, 0x655: 0x9b, 0x656: 0x9b, 0x657: 0x9b,
+	0x658: 0x9b, 0x659: 0x9b, 0x65a: 0x9b, 0x65b: 0x167, 0x65c: 0x9b, 0x65d: 0x168, 0x65e: 0x9b, 0x65f: 0x169,
+	0x660: 0x16a, 0x661: 0x16b, 0x662: 0x16c, 0x663: 0xb8, 0x664: 0x16d, 0x665: 0x16e, 0x666: 0x16f, 0x667: 0x170,
+	0x668: 0xb8, 0x669: 0xb8, 0x66a: 0xb8, 0x66b: 0xb8, 0x66c: 0xb8, 0x66d: 0xb8, 0x66e: 0xb8, 0x66f: 0xb8,
+	0x670: 0xb8, 0x671: 0xb8, 0x672: 0xb8, 0x673: 0xb8, 0x674: 0xb8, 0x675: 0xb8, 0x676: 0xb8, 0x677: 0xb8,
+	0x678: 0xb8, 0x679: 0xb8, 0x67a: 0xb8, 0x67b: 0xb8, 0x67c: 0xb8, 0x67d: 0xb8, 0x67e: 0xb8, 0x67f: 0xb8,
+	// Block 0x1a, offset 0x680
+	0x680: 0x9d, 0x681: 0x9d, 0x682: 0x9d, 0x683: 0x9d, 0x684: 0x9d, 0x685: 0x9d, 0x686: 0x9d, 0x687: 0x9d,
+	0x688: 0x9d, 0x689: 0x9d, 0x68a: 0x9d, 0x68b: 0x9d, 0x68c: 0x9d, 0x68d: 0x9d, 0x68e: 0x9d, 0x68f: 0x9d,
+	0x690: 0x9d, 0x691: 0x9d, 0x692: 0x9d, 0x693: 0x9d, 0x694: 0x9d, 0x695: 0x9d, 0x696: 0x9d, 0x697: 0x9d,
+	0x698: 0x9d, 0x699: 0x9d, 0x69a: 0x9d, 0x69b: 0x171, 0x69c: 0x9d, 0x69d: 0x9d, 0x69e: 0x9d, 0x69f: 0x9d,
+	0x6a0: 0x9d, 0x6a1: 0x9d, 0x6a2: 0x9d, 0x6a3: 0x9d, 0x6a4: 0x9d, 0x6a5: 0x9d, 0x6a6: 0x9d, 0x6a7: 0x9d,
+	0x6a8: 0x9d, 0x6a9: 0x9d, 0x6aa: 0x9d, 0x6ab: 0x9d, 0x6ac: 0x9d, 0x6ad: 0x9d, 0x6ae: 0x9d, 0x6af: 0x9d,
+	0x6b0: 0x9d, 0x6b1: 0x9d, 0x6b2: 0x9d, 0x6b3: 0x9d, 0x6b4: 0x9d, 0x6b5: 0x9d, 0x6b6: 0x9d, 0x6b7: 0x9d,
+	0x6b8: 0x9d, 0x6b9: 0x9d, 0x6ba: 0x9d, 0x6bb: 0x9d, 0x6bc: 0x9d, 0x6bd: 0x9d, 0x6be: 0x9d, 0x6bf: 0x9d,
+	// Block 0x1b, offset 0x6c0
+	0x6c0: 0x9d, 0x6c1: 0x9d, 0x6c2: 0x9d, 0x6c3: 0x9d, 0x6c4: 0x9d, 0x6c5: 0x9d, 0x6c6: 0x9d, 0x6c7: 0x9d,
+	0x6c8: 0x9d, 0x6c9: 0x9d, 0x6ca: 0x9d, 0x6cb: 0x9d, 0x6cc: 0x9d, 0x6cd: 0x9d, 0x6ce: 0x9d, 0x6cf: 0x9d,
+	0x6d0: 0x9d, 0x6d1: 0x9d, 0x6d2: 0x9d, 0x6d3: 0x9d, 0x6d4: 0x9d, 0x6d5: 0x9d, 0x6d6: 0x9d, 0x6d7: 0x9d,
+	0x6d8: 0x9d, 0x6d9: 0x9d, 0x6da: 0x9d, 0x6db: 0x9d, 0x6dc: 0x172, 0x6dd: 0x9d, 0x6de: 0x9d, 0x6df: 0x9d,
+	0x6e0: 0x173, 0x6e1: 0x9d, 0x6e2: 0x9d, 0x6e3: 0x9d, 0x6e4: 0x9d, 0x6e5: 0x9d, 0x6e6: 0x9d, 0x6e7: 0x9d,
+	0x6e8: 0x9d, 0x6e9: 0x9d, 0x6ea: 0x9d, 0x6eb: 0x9d, 0x6ec: 0x9d, 0x6ed: 0x9d, 0x6ee: 0x9d, 0x6ef: 0x9d,
+	0x6f0: 0x9d, 0x6f1: 0x9d, 0x6f2: 0x9d, 0x6f3: 0x9d, 0x6f4: 0x9d, 0x6f5: 0x9d, 0x6f6: 0x9d, 0x6f7: 0x9d,
+	0x6f8: 0x9d, 0x6f9: 0x9d, 0x6fa: 0x9d, 0x6fb: 0x9d, 0x6fc: 0x9d, 0x6fd: 0x9d, 0x6fe: 0x9d, 0x6ff: 0x9d,
+	// Block 0x1c, offset 0x700
+	0x700: 0x9d, 0x701: 0x9d, 0x702: 0x9d, 0x703: 0x9d, 0x704: 0x9d, 0x705: 0x9d, 0x706: 0x9d, 0x707: 0x9d,
+	0x708: 0x9d, 0x709: 0x9d, 0x70a: 0x9d, 0x70b: 0x9d, 0x70c: 0x9d, 0x70d: 0x9d, 0x70e: 0x9d, 0x70f: 0x9d,
+	0x710: 0x9d, 0x711: 0x9d, 0x712: 0x9d, 0x713: 0x9d, 0x714: 0x9d, 0x715: 0x9d, 0x716: 0x9d, 0x717: 0x9d,
+	0x718: 0x9d, 0x719: 0x9d, 0x71a: 0x9d, 0x71b: 0x9d, 0x71c: 0x9d, 0x71d: 0x9d, 0x71e: 0x9d, 0x71f: 0x9d,
+	0x720: 0x9d, 0x721: 0x9d, 0x722: 0x9d, 0x723: 0x9d, 0x724: 0x9d, 0x725: 0x9d, 0x726: 0x9d, 0x727: 0x9d,
+	0x728: 0x9d, 0x729: 0x9d, 0x72a: 0x9d, 0x72b: 0x9d, 0x72c: 0x9d, 0x72d: 0x9d, 0x72e: 0x9d, 0x72f: 0x9d,
+	0x730: 0x9d, 0x731: 0x9d, 0x732: 0x9d, 0x733: 0x9d, 0x734: 0x9d, 0x735: 0x9d, 0x736: 0x9d, 0x737: 0x9d,
+	0x738: 0x9d, 0x739: 0x9d, 0x73a: 0x174, 0x73b: 0xb8, 0x73c: 0xb8, 0x73d: 0xb8, 0x73e: 0xb8, 0x73f: 0xb8,
+	// Block 0x1d, offset 0x740
+	0x740: 0xb8, 0x741: 0xb8, 0x742: 0xb8, 0x743: 0xb8, 0x744: 0xb8, 0x745: 0xb8, 0x746: 0xb8, 0x747: 0xb8,
+	0x748: 0xb8, 0x749: 0xb8, 0x74a: 0xb8, 0x74b: 0xb8, 0x74c: 0xb8, 0x74d: 0xb8, 0x74e: 0xb8, 0x74f: 0xb8,
+	0x750: 0xb8, 0x751: 0xb8, 0x752: 0xb8, 0x753: 0xb8, 0x754: 0xb8, 0x755: 0xb8, 0x756: 0xb8, 0x757: 0xb8,
+	0x758: 0xb8, 0x759: 0xb8, 0x75a: 0xb8, 0x75b: 0xb8, 0x75c: 0xb8, 0x75d: 0xb8, 0x75e: 0xb8, 0x75f: 0xb8,
+	0x760: 0x74, 0x761: 0x75, 0x762: 0x76, 0x763: 0x175, 0x764: 0x77, 0x765: 0x78, 0x766: 0x176, 0x767: 0x79,
+	0x768: 0x7a, 0x769: 0xb8, 0x76a: 0xb8, 0x76b: 0xb8, 0x76c: 0xb8, 0x76d: 0xb8, 0x76e: 0xb8, 0x76f: 0xb8,
+	0x770: 0xb8, 0x771: 0xb8, 0x772: 0xb8, 0x773: 0xb8, 0x774: 0xb8, 0x775: 0xb8, 0x776: 0xb8, 0x777: 0xb8,
+	0x778: 0xb8, 0x779: 0xb8, 0x77a: 0xb8, 0x77b: 0xb8, 0x77c: 0xb8, 0x77d: 0xb8, 0x77e: 0xb8, 0x77f: 0xb8,
+	// Block 0x1e, offset 0x780
+	0x790: 0x0d, 0x791: 0x0e, 0x792: 0x0f, 0x793: 0x10, 0x794: 0x11, 0x795: 0x0b, 0x796: 0x12, 0x797: 0x07,
+	0x798: 0x13, 0x799: 0x0b, 0x79a: 0x0b, 0x79b: 0x14, 0x79c: 0x0b, 0x79d: 0x15, 0x79e: 0x16, 0x79f: 0x17,
+	0x7a0: 0x07, 0x7a1: 0x07, 0x7a2: 0x07, 0x7a3: 0x07, 0x7a4: 0x07, 0x7a5: 0x07, 0x7a6: 0x07, 0x7a7: 0x07,
+	0x7a8: 0x07, 0x7a9: 0x07, 0x7aa: 0x18, 0x7ab: 0x19, 0x7ac: 0x1a, 0x7ad: 0x0b, 0x7ae: 0x0b, 0x7af: 0x1b,
+	0x7b0: 0x0b, 0x7b1: 0x0b, 0x7b2: 0x0b, 0x7b3: 0x0b, 0x7b4: 0x0b, 0x7b5: 0x0b, 0x7b6: 0x0b, 0x7b7: 0x0b,
+	0x7b8: 0x0b, 0x7b9: 0x0b, 0x7ba: 0x0b, 0x7bb: 0x0b, 0x7bc: 0x0b, 0x7bd: 0x0b, 0x7be: 0x0b, 0x7bf: 0x0b,
+	// Block 0x1f, offset 0x7c0
+	0x7c0: 0x0b, 0x7c1: 0x0b, 0x7c2: 0x0b, 0x7c3: 0x0b, 0x7c4: 0x0b, 0x7c5: 0x0b, 0x7c6: 0x0b, 0x7c7: 0x0b,
+	0x7c8: 0x0b, 0x7c9: 0x0b, 0x7ca: 0x0b, 0x7cb: 0x0b, 0x7cc: 0x0b, 0x7cd: 0x0b, 0x7ce: 0x0b, 0x7cf: 0x0b,
+	0x7d0: 0x0b, 0x7d1: 0x0b, 0x7d2: 0x0b, 0x7d3: 0x0b, 0x7d4: 0x0b, 0x7d5: 0x0b, 0x7d6: 0x0b, 0x7d7: 0x0b,
+	0x7d8: 0x0b, 0x7d9: 0x0b, 0x7da: 0x0b, 0x7db: 0x0b, 0x7dc: 0x0b, 0x7dd: 0x0b, 0x7de: 0x0b, 0x7df: 0x0b,
+	0x7e0: 0x0b, 0x7e1: 0x0b, 0x7e2: 0x0b, 0x7e3: 0x0b, 0x7e4: 0x0b, 0x7e5: 0x0b, 0x7e6: 0x0b, 0x7e7: 0x0b,
+	0x7e8: 0x0b, 0x7e9: 0x0b, 0x7ea: 0x0b, 0x7eb: 0x0b, 0x7ec: 0x0b, 0x7ed: 0x0b, 0x7ee: 0x0b, 0x7ef: 0x0b,
+	0x7f0: 0x0b, 0x7f1: 0x0b, 0x7f2: 0x0b, 0x7f3: 0x0b, 0x7f4: 0x0b, 0x7f5: 0x0b, 0x7f6: 0x0b, 0x7f7: 0x0b,
+	0x7f8: 0x0b, 0x7f9: 0x0b, 0x7fa: 0x0b, 0x7fb: 0x0b, 0x7fc: 0x0b, 0x7fd: 0x0b, 0x7fe: 0x0b, 0x7ff: 0x0b,
+	// Block 0x20, offset 0x800
+	0x800: 0x177, 0x801: 0x178, 0x802: 0xb8, 0x803: 0xb8, 0x804: 0x179, 0x805: 0x179, 0x806: 0x179, 0x807: 0x17a,
+	0x808: 0xb8, 0x809: 0xb8, 0x80a: 0xb8, 0x80b: 0xb8, 0x80c: 0xb8, 0x80d: 0xb8, 0x80e: 0xb8, 0x80f: 0xb8,
+	0x810: 0xb8, 0x811: 0xb8, 0x812: 0xb8, 0x813: 0xb8, 0x814: 0xb8, 0x815: 0xb8, 0x816: 0xb8, 0x817: 0xb8,
+	0x818: 0xb8, 0x819: 0xb8, 0x81a: 0xb8, 0x81b: 0xb8, 0x81c: 0xb8, 0x81d: 0xb8, 0x81e: 0xb8, 0x81f: 0xb8,
+	0x820: 0xb8, 0x821: 0xb8, 0x822: 0xb8, 0x823: 0xb8, 0x824: 0xb8, 0x825: 0xb8, 0x826: 0xb8, 0x827: 0xb8,
+	0x828: 0xb8, 0x829: 0xb8, 0x82a: 0xb8, 0x82b: 0xb8, 0x82c: 0xb8, 0x82d: 0xb8, 0x82e: 0xb8, 0x82f: 0xb8,
+	0x830: 0xb8, 0x831: 0xb8, 0x832: 0xb8, 0x833: 0xb8, 0x834: 0xb8, 0x835: 0xb8, 0x836: 0xb8, 0x837: 0xb8,
+	0x838: 0xb8, 0x839: 0xb8, 0x83a: 0xb8, 0x83b: 0xb8, 0x83c: 0xb8, 0x83d: 0xb8, 0x83e: 0xb8, 0x83f: 0xb8,
+	// Block 0x21, offset 0x840
+	0x840: 0x0b, 0x841: 0x0b, 0x842: 0x0b, 0x843: 0x0b, 0x844: 0x0b, 0x845: 0x0b, 0x846: 0x0b, 0x847: 0x0b,
+	0x848: 0x0b, 0x849: 0x0b, 0x84a: 0x0b, 0x84b: 0x0b, 0x84c: 0x0b, 0x84d: 0x0b, 0x84e: 0x0b, 0x84f: 0x0b,
+	0x850: 0x0b, 0x851: 0x0b, 0x852: 0x0b, 0x853: 0x0b, 0x854: 0x0b, 0x855: 0x0b, 0x856: 0x0b, 0x857: 0x0b,
+	0x858: 0x0b, 0x859: 0x0b, 0x85a: 0x0b, 0x85b: 0x0b, 0x85c: 0x0b, 0x85d: 0x0b, 0x85e: 0x0b, 0x85f: 0x0b,
+	0x860: 0x1e, 0x861: 0x0b, 0x862: 0x0b, 0x863: 0x0b, 0x864: 0x0b, 0x865: 0x0b, 0x866: 0x0b, 0x867: 0x0b,
+	0x868: 0x0b, 0x869: 0x0b, 0x86a: 0x0b, 0x86b: 0x0b, 0x86c: 0x0b, 0x86d: 0x0b, 0x86e: 0x0b, 0x86f: 0x0b,
+	0x870: 0x0b, 0x871: 0x0b, 0x872: 0x0b, 0x873: 0x0b, 0x874: 0x0b, 0x875: 0x0b, 0x876: 0x0b, 0x877: 0x0b,
+	0x878: 0x0b, 0x879: 0x0b, 0x87a: 0x0b, 0x87b: 0x0b, 0x87c: 0x0b, 0x87d: 0x0b, 0x87e: 0x0b, 0x87f: 0x0b,
+	// Block 0x22, offset 0x880
+	0x880: 0x0b, 0x881: 0x0b, 0x882: 0x0b, 0x883: 0x0b, 0x884: 0x0b, 0x885: 0x0b, 0x886: 0x0b, 0x887: 0x0b,
+	0x888: 0x0b, 0x889: 0x0b, 0x88a: 0x0b, 0x88b: 0x0b, 0x88c: 0x0b, 0x88d: 0x0b, 0x88e: 0x0b, 0x88f: 0x0b,
+}
+
+// idnaSparseOffset: 256 entries, 512 bytes
+var idnaSparseOffset = []uint16{0x0, 0x8, 0x19, 0x25, 0x27, 0x2c, 0x34, 0x3f, 0x4b, 0x5c, 0x60, 0x6f, 0x74, 0x7b, 0x87, 0x95, 0xa3, 0xa8, 0xb1, 0xc1, 0xcf, 0xdc, 0xe8, 0xf9, 0x103, 0x10a, 0x117, 0x128, 0x12f, 0x13a, 0x149, 0x157, 0x161, 0x163, 0x167, 0x169, 0x175, 0x180, 0x188, 0x18e, 0x194, 0x199, 0x19e, 0x1a1, 0x1a5, 0x1ab, 0x1b0, 0x1bc, 0x1c6, 0x1cc, 0x1dd, 0x1e7, 0x1ea, 0x1f2, 0x1f5, 0x202, 0x20a, 0x20e, 0x215, 0x21d, 0x22d, 0x239, 0x23b, 0x245, 0x251, 0x25d, 0x269, 0x271, 0x276, 0x280, 0x291, 0x295, 0x2a0, 0x2a4, 0x2ad, 0x2b5, 0x2bb, 0x2c0, 0x2c3, 0x2c6, 0x2ca, 0x2d0, 0x2d4, 0x2d8, 0x2de, 0x2e5, 0x2eb, 0x2f3, 0x2fa, 0x305, 0x30f, 0x313, 0x316, 0x31c, 0x320, 0x322, 0x325, 0x327, 0x32a, 0x334, 0x337, 0x346, 0x34a, 0x34f, 0x352, 0x356, 0x35b, 0x360, 0x366, 0x36c, 0x37b, 0x381, 0x385, 0x394, 0x399, 0x3a1, 0x3ab, 0x3b6, 0x3be, 0x3cf, 0x3d8, 0x3e8, 0x3f5, 0x3ff, 0x404, 0x411, 0x415, 0x41a, 0x41c, 0x420, 0x422, 0x426, 0x42f, 0x435, 0x439, 0x449, 0x453, 0x458, 0x45b, 0x461, 0x468, 0x46d, 0x471, 0x477, 0x47c, 0x485, 0x48a, 0x490, 0x497, 0x49e, 0x4a5, 0x4a9, 0x4ae, 0x4b1, 0x4b6, 0x4c2, 0x4c8, 0x4cd, 0x4d4, 0x4dc, 0x4e1, 0x4e5, 0x4f5, 0x4fc, 0x500, 0x504, 0x50b, 0x50e, 0x511, 0x515, 0x519, 0x51f, 0x528, 0x534, 0x53b, 0x544, 0x54c, 0x553, 0x561, 0x56e, 0x57b, 0x584, 0x588, 0x596, 0x59e, 0x5a9, 0x5b2, 0x5b8, 0x5c0, 0x5c9, 0x5d3, 0x5d6, 0x5e2, 0x5e5, 0x5ea, 0x5ed, 0x5f7, 0x600, 0x60c, 0x60f, 0x614, 0x617, 0x61a, 0x61d, 0x624, 0x62b, 0x62f, 0x63a, 0x63d, 0x643, 0x648, 0x64c, 0x64f, 0x652, 0x655, 0x65a, 0x664, 0x667, 0x66b, 0x67a, 0x686, 0x68a, 0x68f, 0x694, 0x698, 0x69d, 0x6a6, 0x6b1, 0x6b7, 0x6bf, 0x6c3, 0x6c7, 0x6cd, 0x6d3, 0x6d8, 0x6db, 0x6e9, 0x6f0, 0x6f3, 0x6f6, 0x6fa, 0x700, 0x705, 0x70f, 0x714, 0x717, 0x71a, 0x71d, 0x720, 0x724, 0x727, 0x737, 0x748, 0x74d, 0x74f, 0x751}
+
+// idnaSparseValues: 1876 entries, 7504 bytes
+var idnaSparseValues = [1876]valueRange{
+	// Block 0x0, offset 0x0
+	{value: 0x0000, lo: 0x07},
+	{value: 0xe105, lo: 0x80, hi: 0x96},
+	{value: 0x0018, lo: 0x97, hi: 0x97},
+	{value: 0xe105, lo: 0x98, hi: 0x9e},
+	{value: 0x001f, lo: 0x9f, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xb6},
+	{value: 0x0018, lo: 0xb7, hi: 0xb7},
+	{value: 0x0008, lo: 0xb8, hi: 0xbf},
+	// Block 0x1, offset 0x8
+	{value: 0x0000, lo: 0x10},
+	{value: 0x0008, lo: 0x80, hi: 0x80},
+	{value: 0xe01d, lo: 0x81, hi: 0x81},
+	{value: 0x0008, lo: 0x82, hi: 0x82},
+	{value: 0x0335, lo: 0x83, hi: 0x83},
+	{value: 0x034d, lo: 0x84, hi: 0x84},
+	{value: 0x0365, lo: 0x85, hi: 0x85},
+	{value: 0xe00d, lo: 0x86, hi: 0x86},
+	{value: 0x0008, lo: 0x87, hi: 0x87},
+	{value: 0xe00d, lo: 0x88, hi: 0x88},
+	{value: 0x0008, lo: 0x89, hi: 0x89},
+	{value: 0xe00d, lo: 0x8a, hi: 0x8a},
+	{value: 0x0008, lo: 0x8b, hi: 0x8b},
+	{value: 0xe00d, lo: 0x8c, hi: 0x8c},
+	{value: 0x0008, lo: 0x8d, hi: 0x8d},
+	{value: 0xe00d, lo: 0x8e, hi: 0x8e},
+	{value: 0x0008, lo: 0x8f, hi: 0xbf},
+	// Block 0x2, offset 0x19
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0xaf},
+	{value: 0x0249, lo: 0xb0, hi: 0xb0},
+	{value: 0x037d, lo: 0xb1, hi: 0xb1},
+	{value: 0x0259, lo: 0xb2, hi: 0xb2},
+	{value: 0x0269, lo: 0xb3, hi: 0xb3},
+	{value: 0x034d, lo: 0xb4, hi: 0xb4},
+	{value: 0x0395, lo: 0xb5, hi: 0xb5},
+	{value: 0xe1bd, lo: 0xb6, hi: 0xb6},
+	{value: 0x0279, lo: 0xb7, hi: 0xb7},
+	{value: 0x0289, lo: 0xb8, hi: 0xb8},
+	{value: 0x0008, lo: 0xb9, hi: 0xbf},
+	// Block 0x3, offset 0x25
+	{value: 0x0000, lo: 0x01},
+	{value: 0x1308, lo: 0x80, hi: 0xbf},
+	// Block 0x4, offset 0x27
+	{value: 0x0000, lo: 0x04},
+	{value: 0x03f5, lo: 0x80, hi: 0x8f},
+	{value: 0xe105, lo: 0x90, hi: 0x9f},
+	{value: 0x049d, lo: 0xa0, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x5, offset 0x2c
+	{value: 0x0000, lo: 0x07},
+	{value: 0xe185, lo: 0x80, hi: 0x8f},
+	{value: 0x0545, lo: 0x90, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x98},
+	{value: 0x0008, lo: 0x99, hi: 0x99},
+	{value: 0x0018, lo: 0x9a, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xa0},
+	{value: 0x0008, lo: 0xa1, hi: 0xbf},
+	// Block 0x6, offset 0x34
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x0008, lo: 0x80, hi: 0x86},
+	{value: 0x0401, lo: 0x87, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x88},
+	{value: 0x0018, lo: 0x89, hi: 0x8a},
+	{value: 0x0040, lo: 0x8b, hi: 0x8c},
+	{value: 0x0018, lo: 0x8d, hi: 0x8f},
+	{value: 0x0040, lo: 0x90, hi: 0x90},
+	{value: 0x1308, lo: 0x91, hi: 0xbd},
+	{value: 0x0018, lo: 0xbe, hi: 0xbe},
+	{value: 0x1308, lo: 0xbf, hi: 0xbf},
+	// Block 0x7, offset 0x3f
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0018, lo: 0x80, hi: 0x80},
+	{value: 0x1308, lo: 0x81, hi: 0x82},
+	{value: 0x0018, lo: 0x83, hi: 0x83},
+	{value: 0x1308, lo: 0x84, hi: 0x85},
+	{value: 0x0018, lo: 0x86, hi: 0x86},
+	{value: 0x1308, lo: 0x87, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xaa},
+	{value: 0x0040, lo: 0xab, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xbf},
+	// Block 0x8, offset 0x4b
+	{value: 0x0000, lo: 0x10},
+	{value: 0x0018, lo: 0x80, hi: 0x80},
+	{value: 0x0208, lo: 0x81, hi: 0x87},
+	{value: 0x0408, lo: 0x88, hi: 0x88},
+	{value: 0x0208, lo: 0x89, hi: 0x8a},
+	{value: 0x1308, lo: 0x8b, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa9},
+	{value: 0x0018, lo: 0xaa, hi: 0xad},
+	{value: 0x0208, lo: 0xae, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xb0},
+	{value: 0x0408, lo: 0xb1, hi: 0xb3},
+	{value: 0x0008, lo: 0xb4, hi: 0xb4},
+	{value: 0x0429, lo: 0xb5, hi: 0xb5},
+	{value: 0x0451, lo: 0xb6, hi: 0xb6},
+	{value: 0x0479, lo: 0xb7, hi: 0xb7},
+	{value: 0x04a1, lo: 0xb8, hi: 0xb8},
+	{value: 0x0208, lo: 0xb9, hi: 0xbf},
+	// Block 0x9, offset 0x5c
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0208, lo: 0x80, hi: 0x87},
+	{value: 0x0408, lo: 0x88, hi: 0x99},
+	{value: 0x0208, lo: 0x9a, hi: 0xbf},
+	// Block 0xa, offset 0x60
+	{value: 0x0000, lo: 0x0e},
+	{value: 0x1308, lo: 0x80, hi: 0x8a},
+	{value: 0x0040, lo: 0x8b, hi: 0x8c},
+	{value: 0x0408, lo: 0x8d, hi: 0x8d},
+	{value: 0x0208, lo: 0x8e, hi: 0x98},
+	{value: 0x0408, lo: 0x99, hi: 0x9b},
+	{value: 0x0208, lo: 0x9c, hi: 0xaa},
+	{value: 0x0408, lo: 0xab, hi: 0xac},
+	{value: 0x0208, lo: 0xad, hi: 0xb0},
+	{value: 0x0408, lo: 0xb1, hi: 0xb1},
+	{value: 0x0208, lo: 0xb2, hi: 0xb2},
+	{value: 0x0408, lo: 0xb3, hi: 0xb4},
+	{value: 0x0208, lo: 0xb5, hi: 0xb7},
+	{value: 0x0408, lo: 0xb8, hi: 0xb9},
+	{value: 0x0208, lo: 0xba, hi: 0xbf},
+	// Block 0xb, offset 0x6f
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xa5},
+	{value: 0x1308, lo: 0xa6, hi: 0xb0},
+	{value: 0x0008, lo: 0xb1, hi: 0xb1},
+	{value: 0x0040, lo: 0xb2, hi: 0xbf},
+	// Block 0xc, offset 0x74
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0008, lo: 0x80, hi: 0x89},
+	{value: 0x0208, lo: 0x8a, hi: 0xaa},
+	{value: 0x1308, lo: 0xab, hi: 0xb3},
+	{value: 0x0008, lo: 0xb4, hi: 0xb5},
+	{value: 0x0018, lo: 0xb6, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbf},
+	// Block 0xd, offset 0x7b
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0x95},
+	{value: 0x1308, lo: 0x96, hi: 0x99},
+	{value: 0x0008, lo: 0x9a, hi: 0x9a},
+	{value: 0x1308, lo: 0x9b, hi: 0xa3},
+	{value: 0x0008, lo: 0xa4, hi: 0xa4},
+	{value: 0x1308, lo: 0xa5, hi: 0xa7},
+	{value: 0x0008, lo: 0xa8, hi: 0xa8},
+	{value: 0x1308, lo: 0xa9, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0xe, offset 0x87
+	{value: 0x0000, lo: 0x0d},
+	{value: 0x0408, lo: 0x80, hi: 0x80},
+	{value: 0x0208, lo: 0x81, hi: 0x85},
+	{value: 0x0408, lo: 0x86, hi: 0x87},
+	{value: 0x0208, lo: 0x88, hi: 0x88},
+	{value: 0x0408, lo: 0x89, hi: 0x89},
+	{value: 0x0208, lo: 0x8a, hi: 0x93},
+	{value: 0x0408, lo: 0x94, hi: 0x94},
+	{value: 0x0208, lo: 0x95, hi: 0x95},
+	{value: 0x0008, lo: 0x96, hi: 0x98},
+	{value: 0x1308, lo: 0x99, hi: 0x9b},
+	{value: 0x0040, lo: 0x9c, hi: 0x9d},
+	{value: 0x0018, lo: 0x9e, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0xbf},
+	// Block 0xf, offset 0x95
+	{value: 0x0000, lo: 0x0d},
+	{value: 0x0040, lo: 0x80, hi: 0x9f},
+	{value: 0x0208, lo: 0xa0, hi: 0xa9},
+	{value: 0x0408, lo: 0xaa, hi: 0xac},
+	{value: 0x0008, lo: 0xad, hi: 0xad},
+	{value: 0x0408, lo: 0xae, hi: 0xae},
+	{value: 0x0208, lo: 0xaf, hi: 0xb0},
+	{value: 0x0408, lo: 0xb1, hi: 0xb2},
+	{value: 0x0208, lo: 0xb3, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xb5},
+	{value: 0x0208, lo: 0xb6, hi: 0xb8},
+	{value: 0x0408, lo: 0xb9, hi: 0xb9},
+	{value: 0x0208, lo: 0xba, hi: 0xbd},
+	{value: 0x0040, lo: 0xbe, hi: 0xbf},
+	// Block 0x10, offset 0xa3
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0040, lo: 0x80, hi: 0x93},
+	{value: 0x1308, lo: 0x94, hi: 0xa1},
+	{value: 0x0040, lo: 0xa2, hi: 0xa2},
+	{value: 0x1308, lo: 0xa3, hi: 0xbf},
+	// Block 0x11, offset 0xa8
+	{value: 0x0000, lo: 0x08},
+	{value: 0x1308, lo: 0x80, hi: 0x82},
+	{value: 0x1008, lo: 0x83, hi: 0x83},
+	{value: 0x0008, lo: 0x84, hi: 0xb9},
+	{value: 0x1308, lo: 0xba, hi: 0xba},
+	{value: 0x1008, lo: 0xbb, hi: 0xbb},
+	{value: 0x1308, lo: 0xbc, hi: 0xbc},
+	{value: 0x0008, lo: 0xbd, hi: 0xbd},
+	{value: 0x1008, lo: 0xbe, hi: 0xbf},
+	// Block 0x12, offset 0xb1
+	{value: 0x0000, lo: 0x0f},
+	{value: 0x1308, lo: 0x80, hi: 0x80},
+	{value: 0x1008, lo: 0x81, hi: 0x82},
+	{value: 0x0040, lo: 0x83, hi: 0x85},
+	{value: 0x1008, lo: 0x86, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x89},
+	{value: 0x1008, lo: 0x8a, hi: 0x8c},
+	{value: 0x1b08, lo: 0x8d, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x90},
+	{value: 0x0040, lo: 0x91, hi: 0x96},
+	{value: 0x1008, lo: 0x97, hi: 0x97},
+	{value: 0x0040, lo: 0x98, hi: 0xa5},
+	{value: 0x0008, lo: 0xa6, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbf},
+	// Block 0x13, offset 0xc1
+	{value: 0x0000, lo: 0x0d},
+	{value: 0x1308, lo: 0x80, hi: 0x80},
+	{value: 0x1008, lo: 0x81, hi: 0x83},
+	{value: 0x0040, lo: 0x84, hi: 0x84},
+	{value: 0x0008, lo: 0x85, hi: 0x8c},
+	{value: 0x0040, lo: 0x8d, hi: 0x8d},
+	{value: 0x0008, lo: 0x8e, hi: 0x90},
+	{value: 0x0040, lo: 0x91, hi: 0x91},
+	{value: 0x0008, lo: 0x92, hi: 0xa8},
+	{value: 0x0040, lo: 0xa9, hi: 0xa9},
+	{value: 0x0008, lo: 0xaa, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbc},
+	{value: 0x0008, lo: 0xbd, hi: 0xbd},
+	{value: 0x1308, lo: 0xbe, hi: 0xbf},
+	// Block 0x14, offset 0xcf
+	{value: 0x0000, lo: 0x0c},
+	{value: 0x0040, lo: 0x80, hi: 0x80},
+	{value: 0x1308, lo: 0x81, hi: 0x81},
+	{value: 0x1008, lo: 0x82, hi: 0x83},
+	{value: 0x0040, lo: 0x84, hi: 0x84},
+	{value: 0x0008, lo: 0x85, hi: 0x8c},
+	{value: 0x0040, lo: 0x8d, hi: 0x8d},
+	{value: 0x0008, lo: 0x8e, hi: 0x90},
+	{value: 0x0040, lo: 0x91, hi: 0x91},
+	{value: 0x0008, lo: 0x92, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbc},
+	{value: 0x0008, lo: 0xbd, hi: 0xbd},
+	{value: 0x1008, lo: 0xbe, hi: 0xbf},
+	// Block 0x15, offset 0xdc
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0040, lo: 0x80, hi: 0x81},
+	{value: 0x1008, lo: 0x82, hi: 0x83},
+	{value: 0x0040, lo: 0x84, hi: 0x84},
+	{value: 0x0008, lo: 0x85, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x99},
+	{value: 0x0008, lo: 0x9a, hi: 0xb1},
+	{value: 0x0040, lo: 0xb2, hi: 0xb2},
+	{value: 0x0008, lo: 0xb3, hi: 0xbb},
+	{value: 0x0040, lo: 0xbc, hi: 0xbc},
+	{value: 0x0008, lo: 0xbd, hi: 0xbd},
+	{value: 0x0040, lo: 0xbe, hi: 0xbf},
+	// Block 0x16, offset 0xe8
+	{value: 0x0000, lo: 0x10},
+	{value: 0x0008, lo: 0x80, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x89},
+	{value: 0x1b08, lo: 0x8a, hi: 0x8a},
+	{value: 0x0040, lo: 0x8b, hi: 0x8e},
+	{value: 0x1008, lo: 0x8f, hi: 0x91},
+	{value: 0x1308, lo: 0x92, hi: 0x94},
+	{value: 0x0040, lo: 0x95, hi: 0x95},
+	{value: 0x1308, lo: 0x96, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x97},
+	{value: 0x1008, lo: 0x98, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xa5},
+	{value: 0x0008, lo: 0xa6, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xb1},
+	{value: 0x1008, lo: 0xb2, hi: 0xb3},
+	{value: 0x0018, lo: 0xb4, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xbf},
+	// Block 0x17, offset 0xf9
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0040, lo: 0x80, hi: 0x80},
+	{value: 0x0008, lo: 0x81, hi: 0xb0},
+	{value: 0x1308, lo: 0xb1, hi: 0xb1},
+	{value: 0x0008, lo: 0xb2, hi: 0xb2},
+	{value: 0x08f1, lo: 0xb3, hi: 0xb3},
+	{value: 0x1308, lo: 0xb4, hi: 0xb9},
+	{value: 0x1b08, lo: 0xba, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbe},
+	{value: 0x0018, lo: 0xbf, hi: 0xbf},
+	// Block 0x18, offset 0x103
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0008, lo: 0x80, hi: 0x86},
+	{value: 0x1308, lo: 0x87, hi: 0x8e},
+	{value: 0x0018, lo: 0x8f, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0018, lo: 0x9a, hi: 0x9b},
+	{value: 0x0040, lo: 0x9c, hi: 0xbf},
+	// Block 0x19, offset 0x10a
+	{value: 0x0000, lo: 0x0c},
+	{value: 0x0008, lo: 0x80, hi: 0x84},
+	{value: 0x0040, lo: 0x85, hi: 0x85},
+	{value: 0x0008, lo: 0x86, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x87},
+	{value: 0x1308, lo: 0x88, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9b},
+	{value: 0x0961, lo: 0x9c, hi: 0x9c},
+	{value: 0x0999, lo: 0x9d, hi: 0x9d},
+	{value: 0x0008, lo: 0x9e, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xbf},
+	// Block 0x1a, offset 0x117
+	{value: 0x0000, lo: 0x10},
+	{value: 0x0008, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0x8a},
+	{value: 0x0008, lo: 0x8b, hi: 0x8b},
+	{value: 0xe03d, lo: 0x8c, hi: 0x8c},
+	{value: 0x0018, lo: 0x8d, hi: 0x97},
+	{value: 0x1308, lo: 0x98, hi: 0x99},
+	{value: 0x0018, lo: 0x9a, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa9},
+	{value: 0x0018, lo: 0xaa, hi: 0xb4},
+	{value: 0x1308, lo: 0xb5, hi: 0xb5},
+	{value: 0x0018, lo: 0xb6, hi: 0xb6},
+	{value: 0x1308, lo: 0xb7, hi: 0xb7},
+	{value: 0x0018, lo: 0xb8, hi: 0xb8},
+	{value: 0x1308, lo: 0xb9, hi: 0xb9},
+	{value: 0x0018, lo: 0xba, hi: 0xbd},
+	{value: 0x1008, lo: 0xbe, hi: 0xbf},
+	// Block 0x1b, offset 0x128
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0018, lo: 0x80, hi: 0x85},
+	{value: 0x1308, lo: 0x86, hi: 0x86},
+	{value: 0x0018, lo: 0x87, hi: 0x8c},
+	{value: 0x0040, lo: 0x8d, hi: 0x8d},
+	{value: 0x0018, lo: 0x8e, hi: 0x9a},
+	{value: 0x0040, lo: 0x9b, hi: 0xbf},
+	// Block 0x1c, offset 0x12f
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x0008, lo: 0x80, hi: 0xaa},
+	{value: 0x1008, lo: 0xab, hi: 0xac},
+	{value: 0x1308, lo: 0xad, hi: 0xb0},
+	{value: 0x1008, lo: 0xb1, hi: 0xb1},
+	{value: 0x1308, lo: 0xb2, hi: 0xb7},
+	{value: 0x1008, lo: 0xb8, hi: 0xb8},
+	{value: 0x1b08, lo: 0xb9, hi: 0xba},
+	{value: 0x1008, lo: 0xbb, hi: 0xbc},
+	{value: 0x1308, lo: 0xbd, hi: 0xbe},
+	{value: 0x0008, lo: 0xbf, hi: 0xbf},
+	// Block 0x1d, offset 0x13a
+	{value: 0x0000, lo: 0x0e},
+	{value: 0x0008, lo: 0x80, hi: 0x89},
+	{value: 0x0018, lo: 0x8a, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x95},
+	{value: 0x1008, lo: 0x96, hi: 0x97},
+	{value: 0x1308, lo: 0x98, hi: 0x99},
+	{value: 0x0008, lo: 0x9a, hi: 0x9d},
+	{value: 0x1308, lo: 0x9e, hi: 0xa0},
+	{value: 0x0008, lo: 0xa1, hi: 0xa1},
+	{value: 0x1008, lo: 0xa2, hi: 0xa4},
+	{value: 0x0008, lo: 0xa5, hi: 0xa6},
+	{value: 0x1008, lo: 0xa7, hi: 0xad},
+	{value: 0x0008, lo: 0xae, hi: 0xb0},
+	{value: 0x1308, lo: 0xb1, hi: 0xb4},
+	{value: 0x0008, lo: 0xb5, hi: 0xbf},
+	// Block 0x1e, offset 0x149
+	{value: 0x0000, lo: 0x0d},
+	{value: 0x0008, lo: 0x80, hi: 0x81},
+	{value: 0x1308, lo: 0x82, hi: 0x82},
+	{value: 0x1008, lo: 0x83, hi: 0x84},
+	{value: 0x1308, lo: 0x85, hi: 0x86},
+	{value: 0x1008, lo: 0x87, hi: 0x8c},
+	{value: 0x1308, lo: 0x8d, hi: 0x8d},
+	{value: 0x0008, lo: 0x8e, hi: 0x8e},
+	{value: 0x1008, lo: 0x8f, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x1008, lo: 0x9a, hi: 0x9c},
+	{value: 0x1308, lo: 0x9d, hi: 0x9d},
+	{value: 0x0018, lo: 0x9e, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xbf},
+	// Block 0x1f, offset 0x157
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0040, lo: 0x80, hi: 0x86},
+	{value: 0x055d, lo: 0x87, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x8c},
+	{value: 0x055d, lo: 0x8d, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xba},
+	{value: 0x0018, lo: 0xbb, hi: 0xbb},
+	{value: 0xe105, lo: 0xbc, hi: 0xbc},
+	{value: 0x0008, lo: 0xbd, hi: 0xbf},
+	// Block 0x20, offset 0x161
+	{value: 0x0000, lo: 0x01},
+	{value: 0x0018, lo: 0x80, hi: 0xbf},
+	// Block 0x21, offset 0x163
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0xa0},
+	{value: 0x0018, lo: 0xa1, hi: 0xbf},
+	// Block 0x22, offset 0x167
+	{value: 0x0000, lo: 0x01},
+	{value: 0x0008, lo: 0x80, hi: 0xbf},
+	// Block 0x23, offset 0x169
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x89},
+	{value: 0x0008, lo: 0x8a, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x97},
+	{value: 0x0008, lo: 0x98, hi: 0x98},
+	{value: 0x0040, lo: 0x99, hi: 0x99},
+	{value: 0x0008, lo: 0x9a, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbf},
+	// Block 0x24, offset 0x175
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x0008, lo: 0x80, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x89},
+	{value: 0x0008, lo: 0x8a, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xb0},
+	{value: 0x0040, lo: 0xb1, hi: 0xb1},
+	{value: 0x0008, lo: 0xb2, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xb7},
+	{value: 0x0008, lo: 0xb8, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0x25, offset 0x180
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0x80},
+	{value: 0x0040, lo: 0x81, hi: 0x81},
+	{value: 0x0008, lo: 0x82, hi: 0x85},
+	{value: 0x0040, lo: 0x86, hi: 0x87},
+	{value: 0x0008, lo: 0x88, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x97},
+	{value: 0x0008, lo: 0x98, hi: 0xbf},
+	// Block 0x26, offset 0x188
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0x90},
+	{value: 0x0040, lo: 0x91, hi: 0x91},
+	{value: 0x0008, lo: 0x92, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0x97},
+	{value: 0x0008, lo: 0x98, hi: 0xbf},
+	// Block 0x27, offset 0x18e
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0x9a},
+	{value: 0x0040, lo: 0x9b, hi: 0x9c},
+	{value: 0x1308, lo: 0x9d, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xbc},
+	{value: 0x0040, lo: 0xbd, hi: 0xbf},
+	// Block 0x28, offset 0x194
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbf},
+	// Block 0x29, offset 0x199
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xb7},
+	{value: 0xe045, lo: 0xb8, hi: 0xbd},
+	{value: 0x0040, lo: 0xbe, hi: 0xbf},
+	// Block 0x2a, offset 0x19e
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0x80},
+	{value: 0x0008, lo: 0x81, hi: 0xbf},
+	// Block 0x2b, offset 0x1a1
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xac},
+	{value: 0x0018, lo: 0xad, hi: 0xae},
+	{value: 0x0008, lo: 0xaf, hi: 0xbf},
+	// Block 0x2c, offset 0x1a5
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0040, lo: 0x80, hi: 0x80},
+	{value: 0x0008, lo: 0x81, hi: 0x9a},
+	{value: 0x0018, lo: 0x9b, hi: 0x9c},
+	{value: 0x0040, lo: 0x9d, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbf},
+	// Block 0x2d, offset 0x1ab
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xaa},
+	{value: 0x0018, lo: 0xab, hi: 0xb0},
+	{value: 0x0008, lo: 0xb1, hi: 0xb8},
+	{value: 0x0040, lo: 0xb9, hi: 0xbf},
+	// Block 0x2e, offset 0x1b0
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0x8c},
+	{value: 0x0040, lo: 0x8d, hi: 0x8d},
+	{value: 0x0008, lo: 0x8e, hi: 0x91},
+	{value: 0x1308, lo: 0x92, hi: 0x93},
+	{value: 0x1b08, lo: 0x94, hi: 0x94},
+	{value: 0x0040, lo: 0x95, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xb1},
+	{value: 0x1308, lo: 0xb2, hi: 0xb3},
+	{value: 0x1b08, lo: 0xb4, hi: 0xb4},
+	{value: 0x0018, lo: 0xb5, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xbf},
+	// Block 0x2f, offset 0x1bc
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0x91},
+	{value: 0x1308, lo: 0x92, hi: 0x93},
+	{value: 0x0040, lo: 0x94, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xac},
+	{value: 0x0040, lo: 0xad, hi: 0xad},
+	{value: 0x0008, lo: 0xae, hi: 0xb0},
+	{value: 0x0040, lo: 0xb1, hi: 0xb1},
+	{value: 0x1308, lo: 0xb2, hi: 0xb3},
+	{value: 0x0040, lo: 0xb4, hi: 0xbf},
+	// Block 0x30, offset 0x1c6
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0xb3},
+	{value: 0x1340, lo: 0xb4, hi: 0xb5},
+	{value: 0x1008, lo: 0xb6, hi: 0xb6},
+	{value: 0x1308, lo: 0xb7, hi: 0xbd},
+	{value: 0x1008, lo: 0xbe, hi: 0xbf},
+	// Block 0x31, offset 0x1cc
+	{value: 0x0000, lo: 0x10},
+	{value: 0x1008, lo: 0x80, hi: 0x85},
+	{value: 0x1308, lo: 0x86, hi: 0x86},
+	{value: 0x1008, lo: 0x87, hi: 0x88},
+	{value: 0x1308, lo: 0x89, hi: 0x91},
+	{value: 0x1b08, lo: 0x92, hi: 0x92},
+	{value: 0x1308, lo: 0x93, hi: 0x93},
+	{value: 0x0018, lo: 0x94, hi: 0x96},
+	{value: 0x0008, lo: 0x97, hi: 0x97},
+	{value: 0x0018, lo: 0x98, hi: 0x9b},
+	{value: 0x0008, lo: 0x9c, hi: 0x9c},
+	{value: 0x1308, lo: 0x9d, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa9},
+	{value: 0x0040, lo: 0xaa, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbf},
+	// Block 0x32, offset 0x1dd
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0018, lo: 0x80, hi: 0x85},
+	{value: 0x0040, lo: 0x86, hi: 0x86},
+	{value: 0x0218, lo: 0x87, hi: 0x87},
+	{value: 0x0018, lo: 0x88, hi: 0x8a},
+	{value: 0x13c0, lo: 0x8b, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9f},
+	{value: 0x0208, lo: 0xa0, hi: 0xbf},
+	// Block 0x33, offset 0x1e7
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0208, lo: 0x80, hi: 0xb7},
+	{value: 0x0040, lo: 0xb8, hi: 0xbf},
+	// Block 0x34, offset 0x1ea
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0x84},
+	{value: 0x1308, lo: 0x85, hi: 0x86},
+	{value: 0x0208, lo: 0x87, hi: 0xa8},
+	{value: 0x1308, lo: 0xa9, hi: 0xa9},
+	{value: 0x0208, lo: 0xaa, hi: 0xaa},
+	{value: 0x0040, lo: 0xab, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x35, offset 0x1f2
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xbf},
+	// Block 0x36, offset 0x1f5
+	{value: 0x0000, lo: 0x0c},
+	{value: 0x0008, lo: 0x80, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0x9f},
+	{value: 0x1308, lo: 0xa0, hi: 0xa2},
+	{value: 0x1008, lo: 0xa3, hi: 0xa6},
+	{value: 0x1308, lo: 0xa7, hi: 0xa8},
+	{value: 0x1008, lo: 0xa9, hi: 0xab},
+	{value: 0x0040, lo: 0xac, hi: 0xaf},
+	{value: 0x1008, lo: 0xb0, hi: 0xb1},
+	{value: 0x1308, lo: 0xb2, hi: 0xb2},
+	{value: 0x1008, lo: 0xb3, hi: 0xb8},
+	{value: 0x1308, lo: 0xb9, hi: 0xbb},
+	{value: 0x0040, lo: 0xbc, hi: 0xbf},
+	// Block 0x37, offset 0x202
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0018, lo: 0x80, hi: 0x80},
+	{value: 0x0040, lo: 0x81, hi: 0x83},
+	{value: 0x0018, lo: 0x84, hi: 0x85},
+	{value: 0x0008, lo: 0x86, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xbf},
+	// Block 0x38, offset 0x20a
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xab},
+	{value: 0x0040, lo: 0xac, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x39, offset 0x20e
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0008, lo: 0x80, hi: 0x89},
+	{value: 0x0040, lo: 0x8a, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0028, lo: 0x9a, hi: 0x9a},
+	{value: 0x0040, lo: 0x9b, hi: 0x9d},
+	{value: 0x0018, lo: 0x9e, hi: 0xbf},
+	// Block 0x3a, offset 0x215
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0x96},
+	{value: 0x1308, lo: 0x97, hi: 0x98},
+	{value: 0x1008, lo: 0x99, hi: 0x9a},
+	{value: 0x1308, lo: 0x9b, hi: 0x9b},
+	{value: 0x0040, lo: 0x9c, hi: 0x9d},
+	{value: 0x0018, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbf},
+	// Block 0x3b, offset 0x21d
+	{value: 0x0000, lo: 0x0f},
+	{value: 0x0008, lo: 0x80, hi: 0x94},
+	{value: 0x1008, lo: 0x95, hi: 0x95},
+	{value: 0x1308, lo: 0x96, hi: 0x96},
+	{value: 0x1008, lo: 0x97, hi: 0x97},
+	{value: 0x1308, lo: 0x98, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0x9f},
+	{value: 0x1b08, lo: 0xa0, hi: 0xa0},
+	{value: 0x1008, lo: 0xa1, hi: 0xa1},
+	{value: 0x1308, lo: 0xa2, hi: 0xa2},
+	{value: 0x1008, lo: 0xa3, hi: 0xa4},
+	{value: 0x1308, lo: 0xa5, hi: 0xac},
+	{value: 0x1008, lo: 0xad, hi: 0xb2},
+	{value: 0x1308, lo: 0xb3, hi: 0xbc},
+	{value: 0x0040, lo: 0xbd, hi: 0xbe},
+	{value: 0x1308, lo: 0xbf, hi: 0xbf},
+	// Block 0x3c, offset 0x22d
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0x89},
+	{value: 0x0040, lo: 0x8a, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xa6},
+	{value: 0x0008, lo: 0xa7, hi: 0xa7},
+	{value: 0x0018, lo: 0xa8, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xbd},
+	{value: 0x1318, lo: 0xbe, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0x3d, offset 0x239
+	{value: 0x0000, lo: 0x01},
+	{value: 0x0040, lo: 0x80, hi: 0xbf},
+	// Block 0x3e, offset 0x23b
+	{value: 0x0000, lo: 0x09},
+	{value: 0x1308, lo: 0x80, hi: 0x83},
+	{value: 0x1008, lo: 0x84, hi: 0x84},
+	{value: 0x0008, lo: 0x85, hi: 0xb3},
+	{value: 0x1308, lo: 0xb4, hi: 0xb4},
+	{value: 0x1008, lo: 0xb5, hi: 0xb5},
+	{value: 0x1308, lo: 0xb6, hi: 0xba},
+	{value: 0x1008, lo: 0xbb, hi: 0xbb},
+	{value: 0x1308, lo: 0xbc, hi: 0xbc},
+	{value: 0x1008, lo: 0xbd, hi: 0xbf},
+	// Block 0x3f, offset 0x245
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x1008, lo: 0x80, hi: 0x81},
+	{value: 0x1308, lo: 0x82, hi: 0x82},
+	{value: 0x1008, lo: 0x83, hi: 0x83},
+	{value: 0x1808, lo: 0x84, hi: 0x84},
+	{value: 0x0008, lo: 0x85, hi: 0x8b},
+	{value: 0x0040, lo: 0x8c, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0018, lo: 0x9a, hi: 0xaa},
+	{value: 0x1308, lo: 0xab, hi: 0xb3},
+	{value: 0x0018, lo: 0xb4, hi: 0xbc},
+	{value: 0x0040, lo: 0xbd, hi: 0xbf},
+	// Block 0x40, offset 0x251
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x1308, lo: 0x80, hi: 0x81},
+	{value: 0x1008, lo: 0x82, hi: 0x82},
+	{value: 0x0008, lo: 0x83, hi: 0xa0},
+	{value: 0x1008, lo: 0xa1, hi: 0xa1},
+	{value: 0x1308, lo: 0xa2, hi: 0xa5},
+	{value: 0x1008, lo: 0xa6, hi: 0xa7},
+	{value: 0x1308, lo: 0xa8, hi: 0xa9},
+	{value: 0x1808, lo: 0xaa, hi: 0xaa},
+	{value: 0x1b08, lo: 0xab, hi: 0xab},
+	{value: 0x1308, lo: 0xac, hi: 0xad},
+	{value: 0x0008, lo: 0xae, hi: 0xbf},
+	// Block 0x41, offset 0x25d
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0xa5},
+	{value: 0x1308, lo: 0xa6, hi: 0xa6},
+	{value: 0x1008, lo: 0xa7, hi: 0xa7},
+	{value: 0x1308, lo: 0xa8, hi: 0xa9},
+	{value: 0x1008, lo: 0xaa, hi: 0xac},
+	{value: 0x1308, lo: 0xad, hi: 0xad},
+	{value: 0x1008, lo: 0xae, hi: 0xae},
+	{value: 0x1308, lo: 0xaf, hi: 0xb1},
+	{value: 0x1808, lo: 0xb2, hi: 0xb3},
+	{value: 0x0040, lo: 0xb4, hi: 0xbb},
+	{value: 0x0018, lo: 0xbc, hi: 0xbf},
+	// Block 0x42, offset 0x269
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0xa3},
+	{value: 0x1008, lo: 0xa4, hi: 0xab},
+	{value: 0x1308, lo: 0xac, hi: 0xb3},
+	{value: 0x1008, lo: 0xb4, hi: 0xb5},
+	{value: 0x1308, lo: 0xb6, hi: 0xb7},
+	{value: 0x0040, lo: 0xb8, hi: 0xba},
+	{value: 0x0018, lo: 0xbb, hi: 0xbf},
+	// Block 0x43, offset 0x271
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x89},
+	{value: 0x0040, lo: 0x8a, hi: 0x8c},
+	{value: 0x0008, lo: 0x8d, hi: 0xbd},
+	{value: 0x0018, lo: 0xbe, hi: 0xbf},
+	// Block 0x44, offset 0x276
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0e29, lo: 0x80, hi: 0x80},
+	{value: 0x0e41, lo: 0x81, hi: 0x81},
+	{value: 0x0e59, lo: 0x82, hi: 0x82},
+	{value: 0x0e71, lo: 0x83, hi: 0x83},
+	{value: 0x0e89, lo: 0x84, hi: 0x85},
+	{value: 0x0ea1, lo: 0x86, hi: 0x86},
+	{value: 0x0eb9, lo: 0x87, hi: 0x87},
+	{value: 0x057d, lo: 0x88, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0xbf},
+	// Block 0x45, offset 0x280
+	{value: 0x0000, lo: 0x10},
+	{value: 0x0018, lo: 0x80, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x8f},
+	{value: 0x1308, lo: 0x90, hi: 0x92},
+	{value: 0x0018, lo: 0x93, hi: 0x93},
+	{value: 0x1308, lo: 0x94, hi: 0xa0},
+	{value: 0x1008, lo: 0xa1, hi: 0xa1},
+	{value: 0x1308, lo: 0xa2, hi: 0xa8},
+	{value: 0x0008, lo: 0xa9, hi: 0xac},
+	{value: 0x1308, lo: 0xad, hi: 0xad},
+	{value: 0x0008, lo: 0xae, hi: 0xb1},
+	{value: 0x1008, lo: 0xb2, hi: 0xb3},
+	{value: 0x1308, lo: 0xb4, hi: 0xb4},
+	{value: 0x0008, lo: 0xb5, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xb7},
+	{value: 0x1308, lo: 0xb8, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbf},
+	// Block 0x46, offset 0x291
+	{value: 0x0000, lo: 0x03},
+	{value: 0x1308, lo: 0x80, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xba},
+	{value: 0x1308, lo: 0xbb, hi: 0xbf},
+	// Block 0x47, offset 0x295
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x0008, lo: 0x80, hi: 0x87},
+	{value: 0xe045, lo: 0x88, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0x97},
+	{value: 0xe045, lo: 0x98, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa7},
+	{value: 0xe045, lo: 0xa8, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb7},
+	{value: 0xe045, lo: 0xb8, hi: 0xbf},
+	// Block 0x48, offset 0x2a0
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0040, lo: 0x80, hi: 0x8f},
+	{value: 0x1318, lo: 0x90, hi: 0xb0},
+	{value: 0x0040, lo: 0xb1, hi: 0xbf},
+	// Block 0x49, offset 0x2a4
+	{value: 0x0000, lo: 0x08},
+	{value: 0x0018, lo: 0x80, hi: 0x82},
+	{value: 0x0040, lo: 0x83, hi: 0x83},
+	{value: 0x0008, lo: 0x84, hi: 0x84},
+	{value: 0x0018, lo: 0x85, hi: 0x88},
+	{value: 0x24c1, lo: 0x89, hi: 0x89},
+	{value: 0x0018, lo: 0x8a, hi: 0x8b},
+	{value: 0x0040, lo: 0x8c, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0xbf},
+	// Block 0x4a, offset 0x2ad
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0018, lo: 0x80, hi: 0xab},
+	{value: 0x24f1, lo: 0xac, hi: 0xac},
+	{value: 0x2529, lo: 0xad, hi: 0xad},
+	{value: 0x0018, lo: 0xae, hi: 0xae},
+	{value: 0x2579, lo: 0xaf, hi: 0xaf},
+	{value: 0x25b1, lo: 0xb0, hi: 0xb0},
+	{value: 0x0018, lo: 0xb1, hi: 0xbf},
+	// Block 0x4b, offset 0x2b5
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0018, lo: 0x80, hi: 0x9f},
+	{value: 0x0080, lo: 0xa0, hi: 0xa0},
+	{value: 0x0018, lo: 0xa1, hi: 0xad},
+	{value: 0x0080, lo: 0xae, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xbf},
+	// Block 0x4c, offset 0x2bb
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0xa8},
+	{value: 0x09c5, lo: 0xa9, hi: 0xa9},
+	{value: 0x09e5, lo: 0xaa, hi: 0xaa},
+	{value: 0x0018, lo: 0xab, hi: 0xbf},
+	// Block 0x4d, offset 0x2c0
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0x4e, offset 0x2c3
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0xa6},
+	{value: 0x0040, lo: 0xa7, hi: 0xbf},
+	// Block 0x4f, offset 0x2c6
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0x8b},
+	{value: 0x28c1, lo: 0x8c, hi: 0x8c},
+	{value: 0x0018, lo: 0x8d, hi: 0xbf},
+	// Block 0x50, offset 0x2ca
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0018, lo: 0x80, hi: 0xb3},
+	{value: 0x0e66, lo: 0xb4, hi: 0xb4},
+	{value: 0x292a, lo: 0xb5, hi: 0xb5},
+	{value: 0x0e86, lo: 0xb6, hi: 0xb6},
+	{value: 0x0018, lo: 0xb7, hi: 0xbf},
+	// Block 0x51, offset 0x2d0
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0x9b},
+	{value: 0x2941, lo: 0x9c, hi: 0x9c},
+	{value: 0x0018, lo: 0x9d, hi: 0xbf},
+	// Block 0x52, offset 0x2d4
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0xb3},
+	{value: 0x0040, lo: 0xb4, hi: 0xb5},
+	{value: 0x0018, lo: 0xb6, hi: 0xbf},
+	// Block 0x53, offset 0x2d8
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0018, lo: 0x80, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0x97},
+	{value: 0x0018, lo: 0x98, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbc},
+	{value: 0x0018, lo: 0xbd, hi: 0xbf},
+	// Block 0x54, offset 0x2de
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0018, lo: 0x80, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x89},
+	{value: 0x0018, lo: 0x8a, hi: 0x91},
+	{value: 0x0040, lo: 0x92, hi: 0xab},
+	{value: 0x0018, lo: 0xac, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xbf},
+	// Block 0x55, offset 0x2e5
+	{value: 0x0000, lo: 0x05},
+	{value: 0xe185, lo: 0x80, hi: 0x8f},
+	{value: 0x03f5, lo: 0x90, hi: 0x9f},
+	{value: 0x0ea5, lo: 0xa0, hi: 0xae},
+	{value: 0x0040, lo: 0xaf, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x56, offset 0x2eb
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0xa5},
+	{value: 0x0040, lo: 0xa6, hi: 0xa6},
+	{value: 0x0008, lo: 0xa7, hi: 0xa7},
+	{value: 0x0040, lo: 0xa8, hi: 0xac},
+	{value: 0x0008, lo: 0xad, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x57, offset 0x2f3
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0008, lo: 0x80, hi: 0xa7},
+	{value: 0x0040, lo: 0xa8, hi: 0xae},
+	{value: 0xe075, lo: 0xaf, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb0},
+	{value: 0x0040, lo: 0xb1, hi: 0xbe},
+	{value: 0x1b08, lo: 0xbf, hi: 0xbf},
+	// Block 0x58, offset 0x2fa
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x0008, lo: 0x80, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa6},
+	{value: 0x0040, lo: 0xa7, hi: 0xa7},
+	{value: 0x0008, lo: 0xa8, hi: 0xae},
+	{value: 0x0040, lo: 0xaf, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xb7},
+	{value: 0x0008, lo: 0xb8, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0x59, offset 0x305
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x87},
+	{value: 0x0008, lo: 0x88, hi: 0x8e},
+	{value: 0x0040, lo: 0x8f, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x97},
+	{value: 0x0008, lo: 0x98, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0x9f},
+	{value: 0x1308, lo: 0xa0, hi: 0xbf},
+	// Block 0x5a, offset 0x30f
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0xae},
+	{value: 0x0008, lo: 0xaf, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xbf},
+	// Block 0x5b, offset 0x313
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0x84},
+	{value: 0x0040, lo: 0x85, hi: 0xbf},
+	// Block 0x5c, offset 0x316
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0018, lo: 0x80, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9a},
+	{value: 0x0018, lo: 0x9b, hi: 0x9e},
+	{value: 0x0edd, lo: 0x9f, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xbf},
+	// Block 0x5d, offset 0x31c
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0xb2},
+	{value: 0x0efd, lo: 0xb3, hi: 0xb3},
+	{value: 0x0040, lo: 0xb4, hi: 0xbf},
+	// Block 0x5e, offset 0x320
+	{value: 0x0020, lo: 0x01},
+	{value: 0x0f1d, lo: 0x80, hi: 0xbf},
+	// Block 0x5f, offset 0x322
+	{value: 0x0020, lo: 0x02},
+	{value: 0x171d, lo: 0x80, hi: 0x8f},
+	{value: 0x18fd, lo: 0x90, hi: 0xbf},
+	// Block 0x60, offset 0x325
+	{value: 0x0020, lo: 0x01},
+	{value: 0x1efd, lo: 0x80, hi: 0xbf},
+	// Block 0x61, offset 0x327
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0040, lo: 0x80, hi: 0x80},
+	{value: 0x0008, lo: 0x81, hi: 0xbf},
+	// Block 0x62, offset 0x32a
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x98},
+	{value: 0x1308, lo: 0x99, hi: 0x9a},
+	{value: 0x29e2, lo: 0x9b, hi: 0x9b},
+	{value: 0x2a0a, lo: 0x9c, hi: 0x9c},
+	{value: 0x0008, lo: 0x9d, hi: 0x9e},
+	{value: 0x2a31, lo: 0x9f, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xa0},
+	{value: 0x0008, lo: 0xa1, hi: 0xbf},
+	// Block 0x63, offset 0x334
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xbe},
+	{value: 0x2a69, lo: 0xbf, hi: 0xbf},
+	// Block 0x64, offset 0x337
+	{value: 0x0000, lo: 0x0e},
+	{value: 0x0040, lo: 0x80, hi: 0x84},
+	{value: 0x0008, lo: 0x85, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xb0},
+	{value: 0x2a1d, lo: 0xb1, hi: 0xb1},
+	{value: 0x2a3d, lo: 0xb2, hi: 0xb2},
+	{value: 0x2a5d, lo: 0xb3, hi: 0xb3},
+	{value: 0x2a7d, lo: 0xb4, hi: 0xb4},
+	{value: 0x2a5d, lo: 0xb5, hi: 0xb5},
+	{value: 0x2a9d, lo: 0xb6, hi: 0xb6},
+	{value: 0x2abd, lo: 0xb7, hi: 0xb7},
+	{value: 0x2add, lo: 0xb8, hi: 0xb9},
+	{value: 0x2afd, lo: 0xba, hi: 0xbb},
+	{value: 0x2b1d, lo: 0xbc, hi: 0xbd},
+	{value: 0x2afd, lo: 0xbe, hi: 0xbf},
+	// Block 0x65, offset 0x346
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0xa3},
+	{value: 0x0040, lo: 0xa4, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x66, offset 0x34a
+	{value: 0x0030, lo: 0x04},
+	{value: 0x2aa2, lo: 0x80, hi: 0x9d},
+	{value: 0x305a, lo: 0x9e, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0x9f},
+	{value: 0x30a2, lo: 0xa0, hi: 0xbf},
+	// Block 0x67, offset 0x34f
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0xbf},
+	// Block 0x68, offset 0x352
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0x8c},
+	{value: 0x0040, lo: 0x8d, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0xbf},
+	// Block 0x69, offset 0x356
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xbd},
+	{value: 0x0018, lo: 0xbe, hi: 0xbf},
+	// Block 0x6a, offset 0x35b
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x8c},
+	{value: 0x0018, lo: 0x8d, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xab},
+	{value: 0x0040, lo: 0xac, hi: 0xbf},
+	// Block 0x6b, offset 0x360
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0xa5},
+	{value: 0x0018, lo: 0xa6, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xb1},
+	{value: 0x0018, lo: 0xb2, hi: 0xb7},
+	{value: 0x0040, lo: 0xb8, hi: 0xbf},
+	// Block 0x6c, offset 0x366
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0040, lo: 0x80, hi: 0xb6},
+	{value: 0x0008, lo: 0xb7, hi: 0xb7},
+	{value: 0x2009, lo: 0xb8, hi: 0xb8},
+	{value: 0x6e89, lo: 0xb9, hi: 0xb9},
+	{value: 0x0008, lo: 0xba, hi: 0xbf},
+	// Block 0x6d, offset 0x36c
+	{value: 0x0000, lo: 0x0e},
+	{value: 0x0008, lo: 0x80, hi: 0x81},
+	{value: 0x1308, lo: 0x82, hi: 0x82},
+	{value: 0x0008, lo: 0x83, hi: 0x85},
+	{value: 0x1b08, lo: 0x86, hi: 0x86},
+	{value: 0x0008, lo: 0x87, hi: 0x8a},
+	{value: 0x1308, lo: 0x8b, hi: 0x8b},
+	{value: 0x0008, lo: 0x8c, hi: 0xa2},
+	{value: 0x1008, lo: 0xa3, hi: 0xa4},
+	{value: 0x1308, lo: 0xa5, hi: 0xa6},
+	{value: 0x1008, lo: 0xa7, hi: 0xa7},
+	{value: 0x0018, lo: 0xa8, hi: 0xab},
+	{value: 0x0040, lo: 0xac, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbf},
+	// Block 0x6e, offset 0x37b
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0208, lo: 0x80, hi: 0xb1},
+	{value: 0x0108, lo: 0xb2, hi: 0xb2},
+	{value: 0x0008, lo: 0xb3, hi: 0xb3},
+	{value: 0x0018, lo: 0xb4, hi: 0xb7},
+	{value: 0x0040, lo: 0xb8, hi: 0xbf},
+	// Block 0x6f, offset 0x381
+	{value: 0x0000, lo: 0x03},
+	{value: 0x1008, lo: 0x80, hi: 0x81},
+	{value: 0x0008, lo: 0x82, hi: 0xb3},
+	{value: 0x1008, lo: 0xb4, hi: 0xbf},
+	// Block 0x70, offset 0x385
+	{value: 0x0000, lo: 0x0e},
+	{value: 0x1008, lo: 0x80, hi: 0x83},
+	{value: 0x1b08, lo: 0x84, hi: 0x84},
+	{value: 0x1308, lo: 0x85, hi: 0x85},
+	{value: 0x0040, lo: 0x86, hi: 0x8d},
+	{value: 0x0018, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9f},
+	{value: 0x1308, lo: 0xa0, hi: 0xb1},
+	{value: 0x0008, lo: 0xb2, hi: 0xb7},
+	{value: 0x0018, lo: 0xb8, hi: 0xba},
+	{value: 0x0008, lo: 0xbb, hi: 0xbb},
+	{value: 0x0018, lo: 0xbc, hi: 0xbc},
+	{value: 0x0008, lo: 0xbd, hi: 0xbd},
+	{value: 0x0040, lo: 0xbe, hi: 0xbf},
+	// Block 0x71, offset 0x394
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xa5},
+	{value: 0x1308, lo: 0xa6, hi: 0xad},
+	{value: 0x0018, lo: 0xae, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x72, offset 0x399
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0x86},
+	{value: 0x1308, lo: 0x87, hi: 0x91},
+	{value: 0x1008, lo: 0x92, hi: 0x92},
+	{value: 0x1808, lo: 0x93, hi: 0x93},
+	{value: 0x0040, lo: 0x94, hi: 0x9e},
+	{value: 0x0018, lo: 0x9f, hi: 0xbc},
+	{value: 0x0040, lo: 0xbd, hi: 0xbf},
+	// Block 0x73, offset 0x3a1
+	{value: 0x0000, lo: 0x09},
+	{value: 0x1308, lo: 0x80, hi: 0x82},
+	{value: 0x1008, lo: 0x83, hi: 0x83},
+	{value: 0x0008, lo: 0x84, hi: 0xb2},
+	{value: 0x1308, lo: 0xb3, hi: 0xb3},
+	{value: 0x1008, lo: 0xb4, hi: 0xb5},
+	{value: 0x1308, lo: 0xb6, hi: 0xb9},
+	{value: 0x1008, lo: 0xba, hi: 0xbb},
+	{value: 0x1308, lo: 0xbc, hi: 0xbc},
+	{value: 0x1008, lo: 0xbd, hi: 0xbf},
+	// Block 0x74, offset 0x3ab
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x1808, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8e},
+	{value: 0x0008, lo: 0x8f, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9d},
+	{value: 0x0018, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa4},
+	{value: 0x1308, lo: 0xa5, hi: 0xa5},
+	{value: 0x0008, lo: 0xa6, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0x75, offset 0x3b6
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0xa8},
+	{value: 0x1308, lo: 0xa9, hi: 0xae},
+	{value: 0x1008, lo: 0xaf, hi: 0xb0},
+	{value: 0x1308, lo: 0xb1, hi: 0xb2},
+	{value: 0x1008, lo: 0xb3, hi: 0xb4},
+	{value: 0x1308, lo: 0xb5, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xbf},
+	// Block 0x76, offset 0x3be
+	{value: 0x0000, lo: 0x10},
+	{value: 0x0008, lo: 0x80, hi: 0x82},
+	{value: 0x1308, lo: 0x83, hi: 0x83},
+	{value: 0x0008, lo: 0x84, hi: 0x8b},
+	{value: 0x1308, lo: 0x8c, hi: 0x8c},
+	{value: 0x1008, lo: 0x8d, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9b},
+	{value: 0x0018, lo: 0x9c, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xb6},
+	{value: 0x0018, lo: 0xb7, hi: 0xb9},
+	{value: 0x0008, lo: 0xba, hi: 0xba},
+	{value: 0x1008, lo: 0xbb, hi: 0xbb},
+	{value: 0x1308, lo: 0xbc, hi: 0xbc},
+	{value: 0x1008, lo: 0xbd, hi: 0xbd},
+	{value: 0x0008, lo: 0xbe, hi: 0xbf},
+	// Block 0x77, offset 0x3cf
+	{value: 0x0000, lo: 0x08},
+	{value: 0x0008, lo: 0x80, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xb0},
+	{value: 0x0008, lo: 0xb1, hi: 0xb1},
+	{value: 0x1308, lo: 0xb2, hi: 0xb4},
+	{value: 0x0008, lo: 0xb5, hi: 0xb6},
+	{value: 0x1308, lo: 0xb7, hi: 0xb8},
+	{value: 0x0008, lo: 0xb9, hi: 0xbd},
+	{value: 0x1308, lo: 0xbe, hi: 0xbf},
+	// Block 0x78, offset 0x3d8
+	{value: 0x0000, lo: 0x0f},
+	{value: 0x0008, lo: 0x80, hi: 0x80},
+	{value: 0x1308, lo: 0x81, hi: 0x81},
+	{value: 0x0008, lo: 0x82, hi: 0x82},
+	{value: 0x0040, lo: 0x83, hi: 0x9a},
+	{value: 0x0008, lo: 0x9b, hi: 0x9d},
+	{value: 0x0018, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xaa},
+	{value: 0x1008, lo: 0xab, hi: 0xab},
+	{value: 0x1308, lo: 0xac, hi: 0xad},
+	{value: 0x1008, lo: 0xae, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb1},
+	{value: 0x0008, lo: 0xb2, hi: 0xb4},
+	{value: 0x1008, lo: 0xb5, hi: 0xb5},
+	{value: 0x1b08, lo: 0xb6, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xbf},
+	// Block 0x79, offset 0x3e8
+	{value: 0x0000, lo: 0x0c},
+	{value: 0x0040, lo: 0x80, hi: 0x80},
+	{value: 0x0008, lo: 0x81, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x88},
+	{value: 0x0008, lo: 0x89, hi: 0x8e},
+	{value: 0x0040, lo: 0x8f, hi: 0x90},
+	{value: 0x0008, lo: 0x91, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa6},
+	{value: 0x0040, lo: 0xa7, hi: 0xa7},
+	{value: 0x0008, lo: 0xa8, hi: 0xae},
+	{value: 0x0040, lo: 0xaf, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x7a, offset 0x3f5
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0x9a},
+	{value: 0x0018, lo: 0x9b, hi: 0x9b},
+	{value: 0x4465, lo: 0x9c, hi: 0x9c},
+	{value: 0x447d, lo: 0x9d, hi: 0x9d},
+	{value: 0x2971, lo: 0x9e, hi: 0x9e},
+	{value: 0xe06d, lo: 0x9f, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa5},
+	{value: 0x0040, lo: 0xa6, hi: 0xaf},
+	{value: 0x4495, lo: 0xb0, hi: 0xbf},
+	// Block 0x7b, offset 0x3ff
+	{value: 0x0000, lo: 0x04},
+	{value: 0x44b5, lo: 0x80, hi: 0x8f},
+	{value: 0x44d5, lo: 0x90, hi: 0x9f},
+	{value: 0x44f5, lo: 0xa0, hi: 0xaf},
+	{value: 0x44d5, lo: 0xb0, hi: 0xbf},
+	// Block 0x7c, offset 0x404
+	{value: 0x0000, lo: 0x0c},
+	{value: 0x0008, lo: 0x80, hi: 0xa2},
+	{value: 0x1008, lo: 0xa3, hi: 0xa4},
+	{value: 0x1308, lo: 0xa5, hi: 0xa5},
+	{value: 0x1008, lo: 0xa6, hi: 0xa7},
+	{value: 0x1308, lo: 0xa8, hi: 0xa8},
+	{value: 0x1008, lo: 0xa9, hi: 0xaa},
+	{value: 0x0018, lo: 0xab, hi: 0xab},
+	{value: 0x1008, lo: 0xac, hi: 0xac},
+	{value: 0x1b08, lo: 0xad, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbf},
+	// Block 0x7d, offset 0x411
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xa3},
+	{value: 0x0040, lo: 0xa4, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xbf},
+	// Block 0x7e, offset 0x415
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x8a},
+	{value: 0x0018, lo: 0x8b, hi: 0xbb},
+	{value: 0x0040, lo: 0xbc, hi: 0xbf},
+	// Block 0x7f, offset 0x41a
+	{value: 0x0020, lo: 0x01},
+	{value: 0x4515, lo: 0x80, hi: 0xbf},
+	// Block 0x80, offset 0x41c
+	{value: 0x0020, lo: 0x03},
+	{value: 0x4d15, lo: 0x80, hi: 0x94},
+	{value: 0x4ad5, lo: 0x95, hi: 0x95},
+	{value: 0x4fb5, lo: 0x96, hi: 0xbf},
+	// Block 0x81, offset 0x420
+	{value: 0x0020, lo: 0x01},
+	{value: 0x54f5, lo: 0x80, hi: 0xbf},
+	// Block 0x82, offset 0x422
+	{value: 0x0020, lo: 0x03},
+	{value: 0x5cf5, lo: 0x80, hi: 0x84},
+	{value: 0x5655, lo: 0x85, hi: 0x85},
+	{value: 0x5d95, lo: 0x86, hi: 0xbf},
+	// Block 0x83, offset 0x426
+	{value: 0x0020, lo: 0x08},
+	{value: 0x6b55, lo: 0x80, hi: 0x8f},
+	{value: 0x6d15, lo: 0x90, hi: 0x90},
+	{value: 0x6d55, lo: 0x91, hi: 0xab},
+	{value: 0x6ea1, lo: 0xac, hi: 0xac},
+	{value: 0x70b5, lo: 0xad, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xae},
+	{value: 0x0040, lo: 0xaf, hi: 0xaf},
+	{value: 0x70d5, lo: 0xb0, hi: 0xbf},
+	// Block 0x84, offset 0x42f
+	{value: 0x0020, lo: 0x05},
+	{value: 0x72d5, lo: 0x80, hi: 0xad},
+	{value: 0x6535, lo: 0xae, hi: 0xae},
+	{value: 0x7895, lo: 0xaf, hi: 0xb5},
+	{value: 0x6f55, lo: 0xb6, hi: 0xb6},
+	{value: 0x7975, lo: 0xb7, hi: 0xbf},
+	// Block 0x85, offset 0x435
+	{value: 0x0028, lo: 0x03},
+	{value: 0x7c21, lo: 0x80, hi: 0x82},
+	{value: 0x7be1, lo: 0x83, hi: 0x83},
+	{value: 0x7c99, lo: 0x84, hi: 0xbf},
+	// Block 0x86, offset 0x439
+	{value: 0x0038, lo: 0x0f},
+	{value: 0x9db1, lo: 0x80, hi: 0x83},
+	{value: 0x9e59, lo: 0x84, hi: 0x85},
+	{value: 0x9e91, lo: 0x86, hi: 0x87},
+	{value: 0x9ec9, lo: 0x88, hi: 0x8f},
+	{value: 0x0040, lo: 0x90, hi: 0x90},
+	{value: 0x0040, lo: 0x91, hi: 0x91},
+	{value: 0xa089, lo: 0x92, hi: 0x97},
+	{value: 0xa1a1, lo: 0x98, hi: 0x9c},
+	{value: 0xa281, lo: 0x9d, hi: 0xb3},
+	{value: 0x9d41, lo: 0xb4, hi: 0xb4},
+	{value: 0x9db1, lo: 0xb5, hi: 0xb5},
+	{value: 0xa789, lo: 0xb6, hi: 0xbb},
+	{value: 0xa869, lo: 0xbc, hi: 0xbc},
+	{value: 0xa7f9, lo: 0xbd, hi: 0xbd},
+	{value: 0xa8d9, lo: 0xbe, hi: 0xbf},
+	// Block 0x87, offset 0x449
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0x8b},
+	{value: 0x0040, lo: 0x8c, hi: 0x8c},
+	{value: 0x0008, lo: 0x8d, hi: 0xa6},
+	{value: 0x0040, lo: 0xa7, hi: 0xa7},
+	{value: 0x0008, lo: 0xa8, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbb},
+	{value: 0x0008, lo: 0xbc, hi: 0xbd},
+	{value: 0x0040, lo: 0xbe, hi: 0xbe},
+	{value: 0x0008, lo: 0xbf, hi: 0xbf},
+	// Block 0x88, offset 0x453
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0xbf},
+	// Block 0x89, offset 0x458
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbf},
+	// Block 0x8a, offset 0x45b
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0018, lo: 0x80, hi: 0x82},
+	{value: 0x0040, lo: 0x83, hi: 0x86},
+	{value: 0x0018, lo: 0x87, hi: 0xb3},
+	{value: 0x0040, lo: 0xb4, hi: 0xb6},
+	{value: 0x0018, lo: 0xb7, hi: 0xbf},
+	// Block 0x8b, offset 0x461
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0018, lo: 0x80, hi: 0x8e},
+	{value: 0x0040, lo: 0x8f, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0x9b},
+	{value: 0x0040, lo: 0x9c, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xa0},
+	{value: 0x0040, lo: 0xa1, hi: 0xbf},
+	// Block 0x8c, offset 0x468
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0040, lo: 0x80, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0xbc},
+	{value: 0x1308, lo: 0xbd, hi: 0xbd},
+	{value: 0x0040, lo: 0xbe, hi: 0xbf},
+	// Block 0x8d, offset 0x46d
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0x9c},
+	{value: 0x0040, lo: 0x9d, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbf},
+	// Block 0x8e, offset 0x471
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0x90},
+	{value: 0x0040, lo: 0x91, hi: 0x9f},
+	{value: 0x1308, lo: 0xa0, hi: 0xa0},
+	{value: 0x0018, lo: 0xa1, hi: 0xbb},
+	{value: 0x0040, lo: 0xbc, hi: 0xbf},
+	// Block 0x8f, offset 0x477
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xa3},
+	{value: 0x0040, lo: 0xa4, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x90, offset 0x47c
+	{value: 0x0000, lo: 0x08},
+	{value: 0x0008, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0x81},
+	{value: 0x0008, lo: 0x82, hi: 0x89},
+	{value: 0x0018, lo: 0x8a, hi: 0x8a},
+	{value: 0x0040, lo: 0x8b, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xb5},
+	{value: 0x1308, lo: 0xb6, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbf},
+	// Block 0x91, offset 0x485
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0x9e},
+	{value: 0x0018, lo: 0x9f, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbf},
+	// Block 0x92, offset 0x48a
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0x83},
+	{value: 0x0040, lo: 0x84, hi: 0x87},
+	{value: 0x0008, lo: 0x88, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0xbf},
+	// Block 0x93, offset 0x490
+	{value: 0x0000, lo: 0x06},
+	{value: 0xe145, lo: 0x80, hi: 0x87},
+	{value: 0xe1c5, lo: 0x88, hi: 0x8f},
+	{value: 0xe145, lo: 0x90, hi: 0x97},
+	{value: 0x8ad5, lo: 0x98, hi: 0x9f},
+	{value: 0x8aed, lo: 0xa0, hi: 0xa7},
+	{value: 0x0008, lo: 0xa8, hi: 0xbf},
+	// Block 0x94, offset 0x497
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0008, lo: 0x80, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa9},
+	{value: 0x0040, lo: 0xaa, hi: 0xaf},
+	{value: 0x8aed, lo: 0xb0, hi: 0xb7},
+	{value: 0x8ad5, lo: 0xb8, hi: 0xbf},
+	// Block 0x95, offset 0x49e
+	{value: 0x0000, lo: 0x06},
+	{value: 0xe145, lo: 0x80, hi: 0x87},
+	{value: 0xe1c5, lo: 0x88, hi: 0x8f},
+	{value: 0xe145, lo: 0x90, hi: 0x93},
+	{value: 0x0040, lo: 0x94, hi: 0x97},
+	{value: 0x0008, lo: 0x98, hi: 0xbb},
+	{value: 0x0040, lo: 0xbc, hi: 0xbf},
+	// Block 0x96, offset 0x4a5
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xa7},
+	{value: 0x0040, lo: 0xa8, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0x97, offset 0x4a9
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xa3},
+	{value: 0x0040, lo: 0xa4, hi: 0xae},
+	{value: 0x0018, lo: 0xaf, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xbf},
+	// Block 0x98, offset 0x4ae
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xbf},
+	// Block 0x99, offset 0x4b1
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa7},
+	{value: 0x0040, lo: 0xa8, hi: 0xbf},
+	// Block 0x9a, offset 0x4b6
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0x85},
+	{value: 0x0040, lo: 0x86, hi: 0x87},
+	{value: 0x0008, lo: 0x88, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x89},
+	{value: 0x0008, lo: 0x8a, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xb6},
+	{value: 0x0008, lo: 0xb7, hi: 0xb8},
+	{value: 0x0040, lo: 0xb9, hi: 0xbb},
+	{value: 0x0008, lo: 0xbc, hi: 0xbc},
+	{value: 0x0040, lo: 0xbd, hi: 0xbe},
+	{value: 0x0008, lo: 0xbf, hi: 0xbf},
+	// Block 0x9b, offset 0x4c2
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0x96},
+	{value: 0x0018, lo: 0x97, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xb6},
+	{value: 0x0018, lo: 0xb7, hi: 0xbf},
+	// Block 0x9c, offset 0x4c8
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0xa6},
+	{value: 0x0018, lo: 0xa7, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xbf},
+	// Block 0x9d, offset 0x4cd
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0040, lo: 0x80, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xb2},
+	{value: 0x0040, lo: 0xb3, hi: 0xb3},
+	{value: 0x0008, lo: 0xb4, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xba},
+	{value: 0x0018, lo: 0xbb, hi: 0xbf},
+	// Block 0x9e, offset 0x4d4
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0x95},
+	{value: 0x0018, lo: 0x96, hi: 0x9b},
+	{value: 0x0040, lo: 0x9c, hi: 0x9e},
+	{value: 0x0018, lo: 0x9f, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbe},
+	{value: 0x0018, lo: 0xbf, hi: 0xbf},
+	// Block 0x9f, offset 0x4dc
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xb7},
+	{value: 0x0040, lo: 0xb8, hi: 0xbb},
+	{value: 0x0018, lo: 0xbc, hi: 0xbd},
+	{value: 0x0008, lo: 0xbe, hi: 0xbf},
+	// Block 0xa0, offset 0x4e1
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0x8f},
+	{value: 0x0040, lo: 0x90, hi: 0x91},
+	{value: 0x0018, lo: 0x92, hi: 0xbf},
+	// Block 0xa1, offset 0x4e5
+	{value: 0x0000, lo: 0x0f},
+	{value: 0x0008, lo: 0x80, hi: 0x80},
+	{value: 0x1308, lo: 0x81, hi: 0x83},
+	{value: 0x0040, lo: 0x84, hi: 0x84},
+	{value: 0x1308, lo: 0x85, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x8b},
+	{value: 0x1308, lo: 0x8c, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x93},
+	{value: 0x0040, lo: 0x94, hi: 0x94},
+	{value: 0x0008, lo: 0x95, hi: 0x97},
+	{value: 0x0040, lo: 0x98, hi: 0x98},
+	{value: 0x0008, lo: 0x99, hi: 0xb3},
+	{value: 0x0040, lo: 0xb4, hi: 0xb7},
+	{value: 0x1308, lo: 0xb8, hi: 0xba},
+	{value: 0x0040, lo: 0xbb, hi: 0xbe},
+	{value: 0x1b08, lo: 0xbf, hi: 0xbf},
+	// Block 0xa2, offset 0x4f5
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0018, lo: 0x80, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0x98},
+	{value: 0x0040, lo: 0x99, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbc},
+	{value: 0x0018, lo: 0xbd, hi: 0xbf},
+	// Block 0xa3, offset 0x4fc
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0x9c},
+	{value: 0x0018, lo: 0x9d, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xbf},
+	// Block 0xa4, offset 0x500
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xb8},
+	{value: 0x0018, lo: 0xb9, hi: 0xbf},
+	// Block 0xa5, offset 0x504
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0008, lo: 0x80, hi: 0x95},
+	{value: 0x0040, lo: 0x96, hi: 0x97},
+	{value: 0x0018, lo: 0x98, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xb2},
+	{value: 0x0040, lo: 0xb3, hi: 0xb7},
+	{value: 0x0018, lo: 0xb8, hi: 0xbf},
+	// Block 0xa6, offset 0x50b
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0xbf},
+	// Block 0xa7, offset 0x50e
+	{value: 0x0000, lo: 0x02},
+	{value: 0x03dd, lo: 0x80, hi: 0xb2},
+	{value: 0x0040, lo: 0xb3, hi: 0xbf},
+	// Block 0xa8, offset 0x511
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xb2},
+	{value: 0x0040, lo: 0xb3, hi: 0xb9},
+	{value: 0x0018, lo: 0xba, hi: 0xbf},
+	// Block 0xa9, offset 0x515
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0040, lo: 0x80, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0xaa, offset 0x519
+	{value: 0x0000, lo: 0x05},
+	{value: 0x1008, lo: 0x80, hi: 0x80},
+	{value: 0x1308, lo: 0x81, hi: 0x81},
+	{value: 0x1008, lo: 0x82, hi: 0x82},
+	{value: 0x0008, lo: 0x83, hi: 0xb7},
+	{value: 0x1308, lo: 0xb8, hi: 0xbf},
+	// Block 0xab, offset 0x51f
+	{value: 0x0000, lo: 0x08},
+	{value: 0x1308, lo: 0x80, hi: 0x85},
+	{value: 0x1b08, lo: 0x86, hi: 0x86},
+	{value: 0x0018, lo: 0x87, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x91},
+	{value: 0x0018, lo: 0x92, hi: 0xa5},
+	{value: 0x0008, lo: 0xa6, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xbe},
+	{value: 0x1b08, lo: 0xbf, hi: 0xbf},
+	// Block 0xac, offset 0x528
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x1308, lo: 0x80, hi: 0x81},
+	{value: 0x1008, lo: 0x82, hi: 0x82},
+	{value: 0x0008, lo: 0x83, hi: 0xaf},
+	{value: 0x1008, lo: 0xb0, hi: 0xb2},
+	{value: 0x1308, lo: 0xb3, hi: 0xb6},
+	{value: 0x1008, lo: 0xb7, hi: 0xb8},
+	{value: 0x1b08, lo: 0xb9, hi: 0xb9},
+	{value: 0x1308, lo: 0xba, hi: 0xba},
+	{value: 0x0018, lo: 0xbb, hi: 0xbc},
+	{value: 0x0340, lo: 0xbd, hi: 0xbd},
+	{value: 0x0018, lo: 0xbe, hi: 0xbf},
+	// Block 0xad, offset 0x534
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0018, lo: 0x80, hi: 0x81},
+	{value: 0x0040, lo: 0x82, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xa8},
+	{value: 0x0040, lo: 0xa9, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbf},
+	// Block 0xae, offset 0x53b
+	{value: 0x0000, lo: 0x08},
+	{value: 0x1308, lo: 0x80, hi: 0x82},
+	{value: 0x0008, lo: 0x83, hi: 0xa6},
+	{value: 0x1308, lo: 0xa7, hi: 0xab},
+	{value: 0x1008, lo: 0xac, hi: 0xac},
+	{value: 0x1308, lo: 0xad, hi: 0xb2},
+	{value: 0x1b08, lo: 0xb3, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xb5},
+	{value: 0x0008, lo: 0xb6, hi: 0xbf},
+	// Block 0xaf, offset 0x544
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0018, lo: 0x80, hi: 0x83},
+	{value: 0x0040, lo: 0x84, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xb2},
+	{value: 0x1308, lo: 0xb3, hi: 0xb3},
+	{value: 0x0018, lo: 0xb4, hi: 0xb5},
+	{value: 0x0008, lo: 0xb6, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xbf},
+	// Block 0xb0, offset 0x54c
+	{value: 0x0000, lo: 0x06},
+	{value: 0x1308, lo: 0x80, hi: 0x81},
+	{value: 0x1008, lo: 0x82, hi: 0x82},
+	{value: 0x0008, lo: 0x83, hi: 0xb2},
+	{value: 0x1008, lo: 0xb3, hi: 0xb5},
+	{value: 0x1308, lo: 0xb6, hi: 0xbe},
+	{value: 0x1008, lo: 0xbf, hi: 0xbf},
+	// Block 0xb1, offset 0x553
+	{value: 0x0000, lo: 0x0d},
+	{value: 0x1808, lo: 0x80, hi: 0x80},
+	{value: 0x0008, lo: 0x81, hi: 0x84},
+	{value: 0x0018, lo: 0x85, hi: 0x89},
+	{value: 0x1308, lo: 0x8a, hi: 0x8c},
+	{value: 0x0018, lo: 0x8d, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x9a},
+	{value: 0x0018, lo: 0x9b, hi: 0x9b},
+	{value: 0x0008, lo: 0x9c, hi: 0x9c},
+	{value: 0x0018, lo: 0x9d, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xa0},
+	{value: 0x0018, lo: 0xa1, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xbf},
+	// Block 0xb2, offset 0x561
+	{value: 0x0000, lo: 0x0c},
+	{value: 0x0008, lo: 0x80, hi: 0x91},
+	{value: 0x0040, lo: 0x92, hi: 0x92},
+	{value: 0x0008, lo: 0x93, hi: 0xab},
+	{value: 0x1008, lo: 0xac, hi: 0xae},
+	{value: 0x1308, lo: 0xaf, hi: 0xb1},
+	{value: 0x1008, lo: 0xb2, hi: 0xb3},
+	{value: 0x1308, lo: 0xb4, hi: 0xb4},
+	{value: 0x1808, lo: 0xb5, hi: 0xb5},
+	{value: 0x1308, lo: 0xb6, hi: 0xb7},
+	{value: 0x0018, lo: 0xb8, hi: 0xbd},
+	{value: 0x1308, lo: 0xbe, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0xb3, offset 0x56e
+	{value: 0x0000, lo: 0x0c},
+	{value: 0x0008, lo: 0x80, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x87},
+	{value: 0x0008, lo: 0x88, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x89},
+	{value: 0x0008, lo: 0x8a, hi: 0x8d},
+	{value: 0x0040, lo: 0x8e, hi: 0x8e},
+	{value: 0x0008, lo: 0x8f, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0x9e},
+	{value: 0x0008, lo: 0x9f, hi: 0xa8},
+	{value: 0x0018, lo: 0xa9, hi: 0xa9},
+	{value: 0x0040, lo: 0xaa, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbf},
+	// Block 0xb4, offset 0x57b
+	{value: 0x0000, lo: 0x08},
+	{value: 0x0008, lo: 0x80, hi: 0x9e},
+	{value: 0x1308, lo: 0x9f, hi: 0x9f},
+	{value: 0x1008, lo: 0xa0, hi: 0xa2},
+	{value: 0x1308, lo: 0xa3, hi: 0xa9},
+	{value: 0x1b08, lo: 0xaa, hi: 0xaa},
+	{value: 0x0040, lo: 0xab, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb9},
+	{value: 0x0040, lo: 0xba, hi: 0xbf},
+	// Block 0xb5, offset 0x584
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xb4},
+	{value: 0x1008, lo: 0xb5, hi: 0xb7},
+	{value: 0x1308, lo: 0xb8, hi: 0xbf},
+	// Block 0xb6, offset 0x588
+	{value: 0x0000, lo: 0x0d},
+	{value: 0x1008, lo: 0x80, hi: 0x81},
+	{value: 0x1b08, lo: 0x82, hi: 0x82},
+	{value: 0x1308, lo: 0x83, hi: 0x84},
+	{value: 0x1008, lo: 0x85, hi: 0x85},
+	{value: 0x1308, lo: 0x86, hi: 0x86},
+	{value: 0x0008, lo: 0x87, hi: 0x8a},
+	{value: 0x0018, lo: 0x8b, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9a},
+	{value: 0x0018, lo: 0x9b, hi: 0x9b},
+	{value: 0x0040, lo: 0x9c, hi: 0x9c},
+	{value: 0x0018, lo: 0x9d, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0xbf},
+	// Block 0xb7, offset 0x596
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0xaf},
+	{value: 0x1008, lo: 0xb0, hi: 0xb2},
+	{value: 0x1308, lo: 0xb3, hi: 0xb8},
+	{value: 0x1008, lo: 0xb9, hi: 0xb9},
+	{value: 0x1308, lo: 0xba, hi: 0xba},
+	{value: 0x1008, lo: 0xbb, hi: 0xbe},
+	{value: 0x1308, lo: 0xbf, hi: 0xbf},
+	// Block 0xb8, offset 0x59e
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x1308, lo: 0x80, hi: 0x80},
+	{value: 0x1008, lo: 0x81, hi: 0x81},
+	{value: 0x1b08, lo: 0x82, hi: 0x82},
+	{value: 0x1308, lo: 0x83, hi: 0x83},
+	{value: 0x0008, lo: 0x84, hi: 0x85},
+	{value: 0x0018, lo: 0x86, hi: 0x86},
+	{value: 0x0008, lo: 0x87, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0xbf},
+	// Block 0xb9, offset 0x5a9
+	{value: 0x0000, lo: 0x08},
+	{value: 0x0008, lo: 0x80, hi: 0xae},
+	{value: 0x1008, lo: 0xaf, hi: 0xb1},
+	{value: 0x1308, lo: 0xb2, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xb7},
+	{value: 0x1008, lo: 0xb8, hi: 0xbb},
+	{value: 0x1308, lo: 0xbc, hi: 0xbd},
+	{value: 0x1008, lo: 0xbe, hi: 0xbe},
+	{value: 0x1b08, lo: 0xbf, hi: 0xbf},
+	// Block 0xba, offset 0x5b2
+	{value: 0x0000, lo: 0x05},
+	{value: 0x1308, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0x97},
+	{value: 0x0008, lo: 0x98, hi: 0x9b},
+	{value: 0x1308, lo: 0x9c, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0xbf},
+	// Block 0xbb, offset 0x5b8
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0008, lo: 0x80, hi: 0xaf},
+	{value: 0x1008, lo: 0xb0, hi: 0xb2},
+	{value: 0x1308, lo: 0xb3, hi: 0xba},
+	{value: 0x1008, lo: 0xbb, hi: 0xbc},
+	{value: 0x1308, lo: 0xbd, hi: 0xbd},
+	{value: 0x1008, lo: 0xbe, hi: 0xbe},
+	{value: 0x1b08, lo: 0xbf, hi: 0xbf},
+	// Block 0xbc, offset 0x5c0
+	{value: 0x0000, lo: 0x08},
+	{value: 0x1308, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0x83},
+	{value: 0x0008, lo: 0x84, hi: 0x84},
+	{value: 0x0040, lo: 0x85, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xac},
+	{value: 0x0040, lo: 0xad, hi: 0xbf},
+	// Block 0xbd, offset 0x5c9
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0xaa},
+	{value: 0x1308, lo: 0xab, hi: 0xab},
+	{value: 0x1008, lo: 0xac, hi: 0xac},
+	{value: 0x1308, lo: 0xad, hi: 0xad},
+	{value: 0x1008, lo: 0xae, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xb5},
+	{value: 0x1808, lo: 0xb6, hi: 0xb6},
+	{value: 0x1308, lo: 0xb7, hi: 0xb7},
+	{value: 0x0040, lo: 0xb8, hi: 0xbf},
+	// Block 0xbe, offset 0x5d3
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x89},
+	{value: 0x0040, lo: 0x8a, hi: 0xbf},
+	// Block 0xbf, offset 0x5d6
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9c},
+	{value: 0x1308, lo: 0x9d, hi: 0x9f},
+	{value: 0x1008, lo: 0xa0, hi: 0xa1},
+	{value: 0x1308, lo: 0xa2, hi: 0xa5},
+	{value: 0x1008, lo: 0xa6, hi: 0xa6},
+	{value: 0x1308, lo: 0xa7, hi: 0xaa},
+	{value: 0x1b08, lo: 0xab, hi: 0xab},
+	{value: 0x0040, lo: 0xac, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xb9},
+	{value: 0x0018, lo: 0xba, hi: 0xbf},
+	// Block 0xc0, offset 0x5e2
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0040, lo: 0x80, hi: 0x9f},
+	{value: 0x049d, lo: 0xa0, hi: 0xbf},
+	// Block 0xc1, offset 0x5e5
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xa9},
+	{value: 0x0018, lo: 0xaa, hi: 0xb2},
+	{value: 0x0040, lo: 0xb3, hi: 0xbe},
+	{value: 0x0008, lo: 0xbf, hi: 0xbf},
+	// Block 0xc2, offset 0x5ea
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xb8},
+	{value: 0x0040, lo: 0xb9, hi: 0xbf},
+	// Block 0xc3, offset 0x5ed
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x89},
+	{value: 0x0008, lo: 0x8a, hi: 0xae},
+	{value: 0x1008, lo: 0xaf, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xb7},
+	{value: 0x1308, lo: 0xb8, hi: 0xbd},
+	{value: 0x1008, lo: 0xbe, hi: 0xbe},
+	{value: 0x1b08, lo: 0xbf, hi: 0xbf},
+	// Block 0xc4, offset 0x5f7
+	{value: 0x0000, lo: 0x08},
+	{value: 0x0008, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0x85},
+	{value: 0x0040, lo: 0x86, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0018, lo: 0x9a, hi: 0xac},
+	{value: 0x0040, lo: 0xad, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb1},
+	{value: 0x0008, lo: 0xb2, hi: 0xbf},
+	// Block 0xc5, offset 0x600
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x0008, lo: 0x80, hi: 0x8f},
+	{value: 0x0040, lo: 0x90, hi: 0x91},
+	{value: 0x1308, lo: 0x92, hi: 0xa7},
+	{value: 0x0040, lo: 0xa8, hi: 0xa8},
+	{value: 0x1008, lo: 0xa9, hi: 0xa9},
+	{value: 0x1308, lo: 0xaa, hi: 0xb0},
+	{value: 0x1008, lo: 0xb1, hi: 0xb1},
+	{value: 0x1308, lo: 0xb2, hi: 0xb3},
+	{value: 0x1008, lo: 0xb4, hi: 0xb4},
+	{value: 0x1308, lo: 0xb5, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xbf},
+	// Block 0xc6, offset 0x60c
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0xbf},
+	// Block 0xc7, offset 0x60f
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0xae},
+	{value: 0x0040, lo: 0xaf, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xbf},
+	// Block 0xc8, offset 0x614
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x83},
+	{value: 0x0040, lo: 0x84, hi: 0xbf},
+	// Block 0xc9, offset 0x617
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xae},
+	{value: 0x0040, lo: 0xaf, hi: 0xbf},
+	// Block 0xca, offset 0x61a
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0xbf},
+	// Block 0xcb, offset 0x61d
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0008, lo: 0x80, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa9},
+	{value: 0x0040, lo: 0xaa, hi: 0xad},
+	{value: 0x0018, lo: 0xae, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xbf},
+	// Block 0xcc, offset 0x624
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0040, lo: 0x80, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xb4},
+	{value: 0x0018, lo: 0xb5, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xbf},
+	// Block 0xcd, offset 0x62b
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0xaf},
+	{value: 0x1308, lo: 0xb0, hi: 0xb6},
+	{value: 0x0018, lo: 0xb7, hi: 0xbf},
+	// Block 0xce, offset 0x62f
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x0008, lo: 0x80, hi: 0x83},
+	{value: 0x0018, lo: 0x84, hi: 0x85},
+	{value: 0x0040, lo: 0x86, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9a},
+	{value: 0x0018, lo: 0x9b, hi: 0xa1},
+	{value: 0x0040, lo: 0xa2, hi: 0xa2},
+	{value: 0x0008, lo: 0xa3, hi: 0xb7},
+	{value: 0x0040, lo: 0xb8, hi: 0xbc},
+	{value: 0x0008, lo: 0xbd, hi: 0xbf},
+	// Block 0xcf, offset 0x63a
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x8f},
+	{value: 0x0040, lo: 0x90, hi: 0xbf},
+	// Block 0xd0, offset 0x63d
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0x84},
+	{value: 0x0040, lo: 0x85, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x90},
+	{value: 0x1008, lo: 0x91, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0xd1, offset 0x643
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0040, lo: 0x80, hi: 0x8e},
+	{value: 0x1308, lo: 0x8f, hi: 0x92},
+	{value: 0x0008, lo: 0x93, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xbf},
+	// Block 0xd2, offset 0x648
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0040, lo: 0x80, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xa0},
+	{value: 0x0040, lo: 0xa1, hi: 0xbf},
+	// Block 0xd3, offset 0x64c
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xac},
+	{value: 0x0040, lo: 0xad, hi: 0xbf},
+	// Block 0xd4, offset 0x64f
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xb2},
+	{value: 0x0040, lo: 0xb3, hi: 0xbf},
+	// Block 0xd5, offset 0x652
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x81},
+	{value: 0x0040, lo: 0x82, hi: 0xbf},
+	// Block 0xd6, offset 0x655
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0008, lo: 0x80, hi: 0xaa},
+	{value: 0x0040, lo: 0xab, hi: 0xaf},
+	{value: 0x0008, lo: 0xb0, hi: 0xbc},
+	{value: 0x0040, lo: 0xbd, hi: 0xbf},
+	// Block 0xd7, offset 0x65a
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0008, lo: 0x80, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9b},
+	{value: 0x0018, lo: 0x9c, hi: 0x9c},
+	{value: 0x1308, lo: 0x9d, hi: 0x9e},
+	{value: 0x0018, lo: 0x9f, hi: 0x9f},
+	{value: 0x03c0, lo: 0xa0, hi: 0xa3},
+	{value: 0x0040, lo: 0xa4, hi: 0xbf},
+	// Block 0xd8, offset 0x664
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xbf},
+	// Block 0xd9, offset 0x667
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0xa6},
+	{value: 0x0040, lo: 0xa7, hi: 0xa8},
+	{value: 0x0018, lo: 0xa9, hi: 0xbf},
+	// Block 0xda, offset 0x66b
+	{value: 0x0000, lo: 0x0e},
+	{value: 0x0018, lo: 0x80, hi: 0x9d},
+	{value: 0xb5b9, lo: 0x9e, hi: 0x9e},
+	{value: 0xb601, lo: 0x9f, hi: 0x9f},
+	{value: 0xb649, lo: 0xa0, hi: 0xa0},
+	{value: 0xb6b1, lo: 0xa1, hi: 0xa1},
+	{value: 0xb719, lo: 0xa2, hi: 0xa2},
+	{value: 0xb781, lo: 0xa3, hi: 0xa3},
+	{value: 0xb7e9, lo: 0xa4, hi: 0xa4},
+	{value: 0x1018, lo: 0xa5, hi: 0xa6},
+	{value: 0x1318, lo: 0xa7, hi: 0xa9},
+	{value: 0x0018, lo: 0xaa, hi: 0xac},
+	{value: 0x1018, lo: 0xad, hi: 0xb2},
+	{value: 0x0340, lo: 0xb3, hi: 0xba},
+	{value: 0x1318, lo: 0xbb, hi: 0xbf},
+	// Block 0xdb, offset 0x67a
+	{value: 0x0000, lo: 0x0b},
+	{value: 0x1318, lo: 0x80, hi: 0x82},
+	{value: 0x0018, lo: 0x83, hi: 0x84},
+	{value: 0x1318, lo: 0x85, hi: 0x8b},
+	{value: 0x0018, lo: 0x8c, hi: 0xa9},
+	{value: 0x1318, lo: 0xaa, hi: 0xad},
+	{value: 0x0018, lo: 0xae, hi: 0xba},
+	{value: 0xb851, lo: 0xbb, hi: 0xbb},
+	{value: 0xb899, lo: 0xbc, hi: 0xbc},
+	{value: 0xb8e1, lo: 0xbd, hi: 0xbd},
+	{value: 0xb949, lo: 0xbe, hi: 0xbe},
+	{value: 0xb9b1, lo: 0xbf, hi: 0xbf},
+	// Block 0xdc, offset 0x686
+	{value: 0x0000, lo: 0x03},
+	{value: 0xba19, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0xa8},
+	{value: 0x0040, lo: 0xa9, hi: 0xbf},
+	// Block 0xdd, offset 0x68a
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0x81},
+	{value: 0x1318, lo: 0x82, hi: 0x84},
+	{value: 0x0018, lo: 0x85, hi: 0x85},
+	{value: 0x0040, lo: 0x86, hi: 0xbf},
+	// Block 0xde, offset 0x68f
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xb1},
+	{value: 0x0040, lo: 0xb2, hi: 0xbf},
+	// Block 0xdf, offset 0x694
+	{value: 0x0000, lo: 0x03},
+	{value: 0x1308, lo: 0x80, hi: 0xb6},
+	{value: 0x0018, lo: 0xb7, hi: 0xba},
+	{value: 0x1308, lo: 0xbb, hi: 0xbf},
+	// Block 0xe0, offset 0x698
+	{value: 0x0000, lo: 0x04},
+	{value: 0x1308, lo: 0x80, hi: 0xac},
+	{value: 0x0018, lo: 0xad, hi: 0xb4},
+	{value: 0x1308, lo: 0xb5, hi: 0xb5},
+	{value: 0x0018, lo: 0xb6, hi: 0xbf},
+	// Block 0xe1, offset 0x69d
+	{value: 0x0000, lo: 0x08},
+	{value: 0x0018, lo: 0x80, hi: 0x83},
+	{value: 0x1308, lo: 0x84, hi: 0x84},
+	{value: 0x0018, lo: 0x85, hi: 0x8b},
+	{value: 0x0040, lo: 0x8c, hi: 0x9a},
+	{value: 0x1308, lo: 0x9b, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xa0},
+	{value: 0x1308, lo: 0xa1, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xbf},
+	// Block 0xe2, offset 0x6a6
+	{value: 0x0000, lo: 0x0a},
+	{value: 0x1308, lo: 0x80, hi: 0x86},
+	{value: 0x0040, lo: 0x87, hi: 0x87},
+	{value: 0x1308, lo: 0x88, hi: 0x98},
+	{value: 0x0040, lo: 0x99, hi: 0x9a},
+	{value: 0x1308, lo: 0x9b, hi: 0xa1},
+	{value: 0x0040, lo: 0xa2, hi: 0xa2},
+	{value: 0x1308, lo: 0xa3, hi: 0xa4},
+	{value: 0x0040, lo: 0xa5, hi: 0xa5},
+	{value: 0x1308, lo: 0xa6, hi: 0xaa},
+	{value: 0x0040, lo: 0xab, hi: 0xbf},
+	// Block 0xe3, offset 0x6b1
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0008, lo: 0x80, hi: 0x84},
+	{value: 0x0040, lo: 0x85, hi: 0x86},
+	{value: 0x0018, lo: 0x87, hi: 0x8f},
+	{value: 0x1308, lo: 0x90, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0xbf},
+	// Block 0xe4, offset 0x6b7
+	{value: 0x0000, lo: 0x07},
+	{value: 0x0208, lo: 0x80, hi: 0x83},
+	{value: 0x1308, lo: 0x84, hi: 0x8a},
+	{value: 0x0040, lo: 0x8b, hi: 0x8f},
+	{value: 0x0008, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9d},
+	{value: 0x0018, lo: 0x9e, hi: 0x9f},
+	{value: 0x0040, lo: 0xa0, hi: 0xbf},
+	// Block 0xe5, offset 0x6bf
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0040, lo: 0x80, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb1},
+	{value: 0x0040, lo: 0xb2, hi: 0xbf},
+	// Block 0xe6, offset 0x6c3
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0xab},
+	{value: 0x0040, lo: 0xac, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xbf},
+	// Block 0xe7, offset 0x6c7
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0018, lo: 0x80, hi: 0x93},
+	{value: 0x0040, lo: 0x94, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xae},
+	{value: 0x0040, lo: 0xaf, hi: 0xb0},
+	{value: 0x0018, lo: 0xb1, hi: 0xbf},
+	// Block 0xe8, offset 0x6cd
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0040, lo: 0x80, hi: 0x80},
+	{value: 0x0018, lo: 0x81, hi: 0x8f},
+	{value: 0x0040, lo: 0x90, hi: 0x90},
+	{value: 0x0018, lo: 0x91, hi: 0xb5},
+	{value: 0x0040, lo: 0xb6, hi: 0xbf},
+	// Block 0xe9, offset 0x6d3
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0x8f},
+	{value: 0xc1c1, lo: 0x90, hi: 0x90},
+	{value: 0x0018, lo: 0x91, hi: 0xac},
+	{value: 0x0040, lo: 0xad, hi: 0xbf},
+	// Block 0xea, offset 0x6d8
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0040, lo: 0x80, hi: 0xa5},
+	{value: 0x0018, lo: 0xa6, hi: 0xbf},
+	// Block 0xeb, offset 0x6db
+	{value: 0x0000, lo: 0x0d},
+	{value: 0xc7e9, lo: 0x80, hi: 0x80},
+	{value: 0xc839, lo: 0x81, hi: 0x81},
+	{value: 0xc889, lo: 0x82, hi: 0x82},
+	{value: 0xc8d9, lo: 0x83, hi: 0x83},
+	{value: 0xc929, lo: 0x84, hi: 0x84},
+	{value: 0xc979, lo: 0x85, hi: 0x85},
+	{value: 0xc9c9, lo: 0x86, hi: 0x86},
+	{value: 0xca19, lo: 0x87, hi: 0x87},
+	{value: 0xca69, lo: 0x88, hi: 0x88},
+	{value: 0x0040, lo: 0x89, hi: 0x8f},
+	{value: 0xcab9, lo: 0x90, hi: 0x90},
+	{value: 0xcad9, lo: 0x91, hi: 0x91},
+	{value: 0x0040, lo: 0x92, hi: 0xbf},
+	// Block 0xec, offset 0x6e9
+	{value: 0x0000, lo: 0x06},
+	{value: 0x0018, lo: 0x80, hi: 0x92},
+	{value: 0x0040, lo: 0x93, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xac},
+	{value: 0x0040, lo: 0xad, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb6},
+	{value: 0x0040, lo: 0xb7, hi: 0xbf},
+	// Block 0xed, offset 0x6f0
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0xb3},
+	{value: 0x0040, lo: 0xb4, hi: 0xbf},
+	// Block 0xee, offset 0x6f3
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0x94},
+	{value: 0x0040, lo: 0x95, hi: 0xbf},
+	// Block 0xef, offset 0x6f6
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0018, lo: 0x80, hi: 0x8b},
+	{value: 0x0040, lo: 0x8c, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0xbf},
+	// Block 0xf0, offset 0x6fa
+	{value: 0x0000, lo: 0x05},
+	{value: 0x0018, lo: 0x80, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0x99},
+	{value: 0x0040, lo: 0x9a, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xbf},
+	// Block 0xf1, offset 0x700
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0x87},
+	{value: 0x0040, lo: 0x88, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0xad},
+	{value: 0x0040, lo: 0xae, hi: 0xbf},
+	// Block 0xf2, offset 0x705
+	{value: 0x0000, lo: 0x09},
+	{value: 0x0040, lo: 0x80, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0x9f},
+	{value: 0x0018, lo: 0xa0, hi: 0xa7},
+	{value: 0x0040, lo: 0xa8, hi: 0xaf},
+	{value: 0x0018, lo: 0xb0, hi: 0xb0},
+	{value: 0x0040, lo: 0xb1, hi: 0xb2},
+	{value: 0x0018, lo: 0xb3, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0xf3, offset 0x70f
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0018, lo: 0x80, hi: 0x8b},
+	{value: 0x0040, lo: 0x8c, hi: 0x8f},
+	{value: 0x0018, lo: 0x90, hi: 0x9e},
+	{value: 0x0040, lo: 0x9f, hi: 0xbf},
+	// Block 0xf4, offset 0x714
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0x91},
+	{value: 0x0040, lo: 0x92, hi: 0xbf},
+	// Block 0xf5, offset 0x717
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0018, lo: 0x80, hi: 0x80},
+	{value: 0x0040, lo: 0x81, hi: 0xbf},
+	// Block 0xf6, offset 0x71a
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0x96},
+	{value: 0x0040, lo: 0x97, hi: 0xbf},
+	// Block 0xf7, offset 0x71d
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xb4},
+	{value: 0x0040, lo: 0xb5, hi: 0xbf},
+	// Block 0xf8, offset 0x720
+	{value: 0x0000, lo: 0x03},
+	{value: 0x0008, lo: 0x80, hi: 0x9d},
+	{value: 0x0040, lo: 0x9e, hi: 0x9f},
+	{value: 0x0008, lo: 0xa0, hi: 0xbf},
+	// Block 0xf9, offset 0x724
+	{value: 0x0000, lo: 0x02},
+	{value: 0x0008, lo: 0x80, hi: 0xa1},
+	{value: 0x0040, lo: 0xa2, hi: 0xbf},
+	// Block 0xfa, offset 0x727
+	{value: 0x0020, lo: 0x0f},
+	{value: 0xdeb9, lo: 0x80, hi: 0x89},
+	{value: 0x8dfd, lo: 0x8a, hi: 0x8a},
+	{value: 0xdff9, lo: 0x8b, hi: 0x9c},
+	{value: 0x8e1d, lo: 0x9d, hi: 0x9d},
+	{value: 0xe239, lo: 0x9e, hi: 0xa2},
+	{value: 0x8e3d, lo: 0xa3, hi: 0xa3},
+	{value: 0xe2d9, lo: 0xa4, hi: 0xab},
+	{value: 0x7ed5, lo: 0xac, hi: 0xac},
+	{value: 0xe3d9, lo: 0xad, hi: 0xaf},
+	{value: 0x8e5d, lo: 0xb0, hi: 0xb0},
+	{value: 0xe439, lo: 0xb1, hi: 0xb6},
+	{value: 0x8e7d, lo: 0xb7, hi: 0xb9},
+	{value: 0xe4f9, lo: 0xba, hi: 0xba},
+	{value: 0x8edd, lo: 0xbb, hi: 0xbb},
+	{value: 0xe519, lo: 0xbc, hi: 0xbf},
+	// Block 0xfb, offset 0x737
+	{value: 0x0020, lo: 0x10},
+	{value: 0x937d, lo: 0x80, hi: 0x80},
+	{value: 0xf099, lo: 0x81, hi: 0x86},
+	{value: 0x939d, lo: 0x87, hi: 0x8a},
+	{value: 0xd9f9, lo: 0x8b, hi: 0x8b},
+	{value: 0xf159, lo: 0x8c, hi: 0x96},
+	{value: 0x941d, lo: 0x97, hi: 0x97},
+	{value: 0xf2b9, lo: 0x98, hi: 0xa3},
+	{value: 0x943d, lo: 0xa4, hi: 0xa6},
+	{value: 0xf439, lo: 0xa7, hi: 0xaa},
+	{value: 0x949d, lo: 0xab, hi: 0xab},
+	{value: 0xf4b9, lo: 0xac, hi: 0xac},
+	{value: 0x94bd, lo: 0xad, hi: 0xad},
+	{value: 0xf4d9, lo: 0xae, hi: 0xaf},
+	{value: 0x94dd, lo: 0xb0, hi: 0xb1},
+	{value: 0xf519, lo: 0xb2, hi: 0xbe},
+	{value: 0x0040, lo: 0xbf, hi: 0xbf},
+	// Block 0xfc, offset 0x748
+	{value: 0x0000, lo: 0x04},
+	{value: 0x0040, lo: 0x80, hi: 0x80},
+	{value: 0x0340, lo: 0x81, hi: 0x81},
+	{value: 0x0040, lo: 0x82, hi: 0x9f},
+	{value: 0x0340, lo: 0xa0, hi: 0xbf},
+	// Block 0xfd, offset 0x74d
+	{value: 0x0000, lo: 0x01},
+	{value: 0x0340, lo: 0x80, hi: 0xbf},
+	// Block 0xfe, offset 0x74f
+	{value: 0x0000, lo: 0x01},
+	{value: 0x13c0, lo: 0x80, hi: 0xbf},
+	// Block 0xff, offset 0x751
+	{value: 0x0000, lo: 0x02},
+	{value: 0x13c0, lo: 0x80, hi: 0xaf},
+	{value: 0x0040, lo: 0xb0, hi: 0xbf},
+}
+
+// Total table size 41559 bytes (40KiB); checksum: F4A1FA4E
diff --git a/libgo/go/golang_org/x/net/idna/trie.go b/libgo/go/golang_org/x/net/idna/trie.go
new file mode 100644
index 0000000..000fb97
--- /dev/null
+++ b/libgo/go/golang_org/x/net/idna/trie.go
@@ -0,0 +1,72 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package idna
+
+// appendMapping appends the mapping for the respective rune. isMapped must be
+// true. A mapping is a categorization of a rune as defined in UTS #46.
+func (c info) appendMapping(b []byte, s string) []byte {
+	index := int(c >> indexShift)
+	if c&xorBit == 0 {
+		s := mappings[index:]
+		return append(b, s[1:s[0]+1]...)
+	}
+	b = append(b, s...)
+	if c&inlineXOR == inlineXOR {
+		// TODO: support and handle two-byte inline masks
+		b[len(b)-1] ^= byte(index)
+	} else {
+		for p := len(b) - int(xorData[index]); p < len(b); p++ {
+			index++
+			b[p] ^= xorData[index]
+		}
+	}
+	return b
+}
+
+// Sparse block handling code.
+
+type valueRange struct {
+	value  uint16 // header: value:stride
+	lo, hi byte   // header: lo:n
+}
+
+type sparseBlocks struct {
+	values []valueRange
+	offset []uint16
+}
+
+var idnaSparse = sparseBlocks{
+	values: idnaSparseValues[:],
+	offset: idnaSparseOffset[:],
+}
+
+// Don't use newIdnaTrie to avoid unconditional linking in of the table.
+var trie = &idnaTrie{}
+
+// lookup determines the type of block n and looks up the value for b.
+// For n < t.cutoff, the block is a simple lookup table. Otherwise, the block
+// is a list of ranges with an accompanying value. Given a matching range r,
+// the value for b is by r.value + (b - r.lo) * stride.
+func (t *sparseBlocks) lookup(n uint32, b byte) uint16 {
+	offset := t.offset[n]
+	header := t.values[offset]
+	lo := offset + 1
+	hi := lo + uint16(header.lo)
+	for lo < hi {
+		m := lo + (hi-lo)/2
+		r := t.values[m]
+		if r.lo <= b && b <= r.hi {
+			return r.value + uint16(b-r.lo)*header.value
+		}
+		if b < r.lo {
+			hi = m
+		} else {
+			lo = m + 1
+		}
+	}
+	return 0
+}
diff --git a/libgo/go/golang_org/x/net/idna/trieval.go b/libgo/go/golang_org/x/net/idna/trieval.go
new file mode 100644
index 0000000..cd88e4d
--- /dev/null
+++ b/libgo/go/golang_org/x/net/idna/trieval.go
@@ -0,0 +1,116 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Code generated by running "go generate" in golang_org/x/text. DO NOT EDIT.
+
+package idna
+
+// This file contains definitions for interpreting the trie value of the idna
+// trie generated by "go run gen*.go". It is shared by both the generator
+// program and the resultant package. Sharing is achieved by the generator
+// copying gen_trieval.go to trieval.go and changing what's above this comment.
+
+// info holds information from the IDNA mapping table for a single rune. It is
+// the value returned by a trie lookup. In most cases, all information fits in
+// a 16-bit value. For mappings, this value may contain an index into a slice
+// with the mapped string. Such mappings can consist of the actual mapped value
+// or an XOR pattern to be applied to the bytes of the UTF8 encoding of the
+// input rune. This technique is used by the cases packages and reduces the
+// table size significantly.
+//
+// The per-rune values have the following format:
+//
+//   if mapped {
+//     if inlinedXOR {
+//       15..13 inline XOR marker
+//       12..11 unused
+//       10..3  inline XOR mask
+//     } else {
+//       15..3  index into xor or mapping table
+//     }
+//   } else {
+//       15..13 unused
+//           12 modifier (including virama)
+//           11 virama modifier
+//       10..8  joining type
+//        7..3  category type
+//   }
+//      2  use xor pattern
+//   1..0  mapped category
+//
+// See the definitions below for a more detailed description of the various
+// bits.
+type info uint16
+
+const (
+	catSmallMask = 0x3
+	catBigMask   = 0xF8
+	indexShift   = 3
+	xorBit       = 0x4    // interpret the index as an xor pattern
+	inlineXOR    = 0xE000 // These bits are set if the XOR pattern is inlined.
+
+	joinShift = 8
+	joinMask  = 0x07
+
+	viramaModifier = 0x0800
+	modifier       = 0x1000
+)
+
+// A category corresponds to a category defined in the IDNA mapping table.
+type category uint16
+
+const (
+	unknown              category = 0 // not defined currently in unicode.
+	mapped               category = 1
+	disallowedSTD3Mapped category = 2
+	deviation            category = 3
+)
+
+const (
+	valid               category = 0x08
+	validNV8            category = 0x18
+	validXV8            category = 0x28
+	disallowed          category = 0x40
+	disallowedSTD3Valid category = 0x80
+	ignored             category = 0xC0
+)
+
+// join types and additional rune information
+const (
+	joiningL = (iota + 1)
+	joiningD
+	joiningT
+	joiningR
+
+	//the following types are derived during processing
+	joinZWJ
+	joinZWNJ
+	joinVirama
+	numJoinTypes
+)
+
+func (c info) isMapped() bool {
+	return c&0x3 != 0
+}
+
+func (c info) category() category {
+	small := c & catSmallMask
+	if small != 0 {
+		return category(small)
+	}
+	return category(c & catBigMask)
+}
+
+func (c info) joinType() info {
+	if c.isMapped() {
+		return 0
+	}
+	return (c >> joinShift) & joinMask
+}
+
+func (c info) isModifier() bool {
+	return c&(modifier|catSmallMask) == modifier
+}
+
+func (c info) isViramaModifier() bool {
+	return c&(viramaModifier|catSmallMask) == viramaModifier
+}
diff --git a/libgo/go/golang_org/x/net/lif/address.go b/libgo/go/golang_org/x/net/lif/address.go
index f9b34ae..afb957f 100644
--- a/libgo/go/golang_org/x/net/lif/address.go
+++ b/libgo/go/golang_org/x/net/lif/address.go
@@ -67,7 +67,7 @@
 				continue
 			}
 			sa := (*sockaddrStorage)(unsafe.Pointer(&lifr.Lifru[0]))
-			l := int(littleEndian.Uint32(lifr.Lifru1[:4]))
+			l := int(nativeEndian.Uint32(lifr.Lifru1[:4]))
 			if l == 0 {
 				continue
 			}
@@ -77,7 +77,7 @@
 				copy(a.IP[:], lifr.Lifru[4:8])
 				as = append(as, a)
 			case sysAF_INET6:
-				a := &Inet6Addr{PrefixLen: l, ZoneID: int(littleEndian.Uint32(lifr.Lifru[24:28]))}
+				a := &Inet6Addr{PrefixLen: l, ZoneID: int(nativeEndian.Uint32(lifr.Lifru[24:28]))}
 				copy(a.IP[:], lifr.Lifru[8:24])
 				as = append(as, a)
 			}
diff --git a/libgo/go/golang_org/x/net/lif/address_test.go b/libgo/go/golang_org/x/net/lif/address_test.go
index f62ed93..a25f10b 100644
--- a/libgo/go/golang_org/x/net/lif/address_test.go
+++ b/libgo/go/golang_org/x/net/lif/address_test.go
@@ -78,15 +78,17 @@
 }
 
 func addrPacks() ([]addrPack, error) {
+	var lastErr error
 	var aps []addrPack
 	for _, af := range [...]int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
 		as, err := Addrs(af, "")
 		if err != nil {
-			return nil, err
+			lastErr = err
+			continue
 		}
 		aps = append(aps, addrPack{af: af, as: as})
 	}
-	return aps, nil
+	return aps, lastErr
 }
 
 func TestAddrs(t *testing.T) {
diff --git a/libgo/go/golang_org/x/net/lif/binary.go b/libgo/go/golang_org/x/net/lif/binary.go
index aade9ea..738a94f 100644
--- a/libgo/go/golang_org/x/net/lif/binary.go
+++ b/libgo/go/golang_org/x/net/lif/binary.go
@@ -12,7 +12,10 @@
 // library. Therefore the package set used in the package must be the
 // same as net package.
 
-var littleEndian binaryLittleEndian
+var (
+	littleEndian binaryLittleEndian
+	bigEndian    binaryBigEndian
+)
 
 type binaryByteOrder interface {
 	Uint16([]byte) uint16
@@ -66,3 +69,47 @@
 	b[6] = byte(v >> 48)
 	b[7] = byte(v >> 56)
 }
+
+type binaryBigEndian struct{}
+
+func (binaryBigEndian) Uint16(b []byte) uint16 {
+	_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint16(b[1]) | uint16(b[0])<<8
+}
+
+func (binaryBigEndian) PutUint16(b []byte, v uint16) {
+	_ = b[1] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v >> 8)
+	b[1] = byte(v)
+}
+
+func (binaryBigEndian) Uint32(b []byte) uint32 {
+	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+}
+
+func (binaryBigEndian) PutUint32(b []byte, v uint32) {
+	_ = b[3] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v >> 24)
+	b[1] = byte(v >> 16)
+	b[2] = byte(v >> 8)
+	b[3] = byte(v)
+}
+
+func (binaryBigEndian) Uint64(b []byte) uint64 {
+	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+}
+
+func (binaryBigEndian) PutUint64(b []byte, v uint64) {
+	_ = b[7] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v >> 56)
+	b[1] = byte(v >> 48)
+	b[2] = byte(v >> 40)
+	b[3] = byte(v >> 32)
+	b[4] = byte(v >> 24)
+	b[5] = byte(v >> 16)
+	b[6] = byte(v >> 8)
+	b[7] = byte(v)
+}
diff --git a/libgo/go/golang_org/x/net/lif/defs_solaris.go b/libgo/go/golang_org/x/net/lif/defs_solaris.go
index 8b84ba5..02c1998 100644
--- a/libgo/go/golang_org/x/net/lif/defs_solaris.go
+++ b/libgo/go/golang_org/x/net/lif/defs_solaris.go
@@ -75,7 +75,7 @@
 	sizeofLifIfinfoReq = C.sizeof_struct_lif_ifinfo_req
 )
 
-type sysLifnum C.struct_lifnum
+type lifnum C.struct_lifnum
 
 type lifreq C.struct_lifreq
 
diff --git a/libgo/go/golang_org/x/net/lif/link.go b/libgo/go/golang_org/x/net/lif/link.go
index 6a77a8f..70e0262 100644
--- a/libgo/go/golang_org/x/net/lif/link.go
+++ b/libgo/go/golang_org/x/net/lif/link.go
@@ -31,15 +31,15 @@
 	}
 	ioc := int64(sysSIOCGLIFINDEX)
 	if err := ioctl(s, uintptr(ioc), unsafe.Pointer(&lifr)); err == nil {
-		ll.Index = int(littleEndian.Uint32(lifr.Lifru[:4]))
+		ll.Index = int(nativeEndian.Uint32(lifr.Lifru[:4]))
 	}
 	ioc = int64(sysSIOCGLIFFLAGS)
 	if err := ioctl(s, uintptr(ioc), unsafe.Pointer(&lifr)); err == nil {
-		ll.Flags = int(littleEndian.Uint64(lifr.Lifru[:8]))
+		ll.Flags = int(nativeEndian.Uint64(lifr.Lifru[:8]))
 	}
 	ioc = int64(sysSIOCGLIFMTU)
 	if err := ioctl(s, uintptr(ioc), unsafe.Pointer(&lifr)); err == nil {
-		ll.MTU = int(littleEndian.Uint32(lifr.Lifru[:4]))
+		ll.MTU = int(nativeEndian.Uint32(lifr.Lifru[:4]))
 	}
 	switch ll.Type {
 	case sysIFT_IPV4, sysIFT_IPV6, sysIFT_6TO4:
@@ -70,7 +70,7 @@
 
 func links(eps []endpoint, name string) ([]Link, error) {
 	var lls []Link
-	lifn := sysLifnum{Flags: sysLIFC_NOXMIT | sysLIFC_TEMPORARY | sysLIFC_ALLZONES | sysLIFC_UNDER_IPMP}
+	lifn := lifnum{Flags: sysLIFC_NOXMIT | sysLIFC_TEMPORARY | sysLIFC_ALLZONES | sysLIFC_UNDER_IPMP}
 	lifc := lifconf{Flags: sysLIFC_NOXMIT | sysLIFC_TEMPORARY | sysLIFC_ALLZONES | sysLIFC_UNDER_IPMP}
 	for _, ep := range eps {
 		lifn.Family = uint16(ep.af)
diff --git a/libgo/go/golang_org/x/net/lif/link_test.go b/libgo/go/golang_org/x/net/lif/link_test.go
index 8fb2bf6..0cb9b95c 100644
--- a/libgo/go/golang_org/x/net/lif/link_test.go
+++ b/libgo/go/golang_org/x/net/lif/link_test.go
@@ -21,15 +21,17 @@
 }
 
 func linkPacks() ([]linkPack, error) {
+	var lastErr error
 	var lps []linkPack
 	for _, af := range [...]int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
 		lls, err := Links(af, "")
 		if err != nil {
-			return nil, err
+			lastErr = err
+			continue
 		}
 		lps = append(lps, linkPack{af: af, lls: lls})
 	}
-	return lps, nil
+	return lps, lastErr
 }
 
 func TestLinks(t *testing.T) {
diff --git a/libgo/go/golang_org/x/net/lif/sys.go b/libgo/go/golang_org/x/net/lif/sys.go
new file mode 100644
index 0000000..c896041
--- /dev/null
+++ b/libgo/go/golang_org/x/net/lif/sys.go
@@ -0,0 +1,21 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build solaris
+
+package lif
+
+import "unsafe"
+
+var nativeEndian binaryByteOrder
+
+func init() {
+	i := uint32(1)
+	b := (*[4]byte)(unsafe.Pointer(&i))
+	if b[0] == 1 {
+		nativeEndian = littleEndian
+	} else {
+		nativeEndian = bigEndian
+	}
+}
diff --git a/libgo/go/golang_org/x/net/nettest/conntest.go b/libgo/go/golang_org/x/net/nettest/conntest.go
new file mode 100644
index 0000000..5bd3a8c
--- /dev/null
+++ b/libgo/go/golang_org/x/net/nettest/conntest.go
@@ -0,0 +1,456 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package nettest provides utilities for network testing.
+package nettest
+
+import (
+	"bytes"
+	"encoding/binary"
+	"io"
+	"io/ioutil"
+	"math/rand"
+	"net"
+	"runtime"
+	"sync"
+	"testing"
+	"time"
+)
+
+var (
+	aLongTimeAgo = time.Unix(233431200, 0)
+	neverTimeout = time.Time{}
+)
+
+// MakePipe creates a connection between two endpoints and returns the pair
+// as c1 and c2, such that anything written to c1 is read by c2 and vice-versa.
+// The stop function closes all resources, including c1, c2, and the underlying
+// net.Listener (if there is one), and should not be nil.
+type MakePipe func() (c1, c2 net.Conn, stop func(), err error)
+
+// TestConn tests that a net.Conn implementation properly satisfies the interface.
+// The tests should not produce any false positives, but may experience
+// false negatives. Thus, some issues may only be detected when the test is
+// run multiple times. For maximal effectiveness, run the tests under the
+// race detector.
+func TestConn(t *testing.T, mp MakePipe) {
+	testConn(t, mp)
+}
+
+type connTester func(t *testing.T, c1, c2 net.Conn)
+
+func timeoutWrapper(t *testing.T, mp MakePipe, f connTester) {
+	c1, c2, stop, err := mp()
+	if err != nil {
+		t.Fatalf("unable to make pipe: %v", err)
+	}
+	var once sync.Once
+	defer once.Do(func() { stop() })
+	timer := time.AfterFunc(time.Minute, func() {
+		once.Do(func() {
+			t.Error("test timed out; terminating pipe")
+			stop()
+		})
+	})
+	defer timer.Stop()
+	f(t, c1, c2)
+}
+
+// testBasicIO tests that the data sent on c1 is properly received on c2.
+func testBasicIO(t *testing.T, c1, c2 net.Conn) {
+	want := make([]byte, 1<<20)
+	rand.New(rand.NewSource(0)).Read(want)
+
+	dataCh := make(chan []byte)
+	go func() {
+		rd := bytes.NewReader(want)
+		if err := chunkedCopy(c1, rd); err != nil {
+			t.Errorf("unexpected c1.Write error: %v", err)
+		}
+		if err := c1.Close(); err != nil {
+			t.Errorf("unexpected c1.Close error: %v", err)
+		}
+	}()
+
+	go func() {
+		wr := new(bytes.Buffer)
+		if err := chunkedCopy(wr, c2); err != nil {
+			t.Errorf("unexpected c2.Read error: %v", err)
+		}
+		if err := c2.Close(); err != nil {
+			t.Errorf("unexpected c2.Close error: %v", err)
+		}
+		dataCh <- wr.Bytes()
+	}()
+
+	if got := <-dataCh; !bytes.Equal(got, want) {
+		t.Errorf("transmitted data differs")
+	}
+}
+
+// testPingPong tests that the two endpoints can synchronously send data to
+// each other in a typical request-response pattern.
+func testPingPong(t *testing.T, c1, c2 net.Conn) {
+	var wg sync.WaitGroup
+	defer wg.Wait()
+
+	pingPonger := func(c net.Conn) {
+		defer wg.Done()
+		buf := make([]byte, 8)
+		var prev uint64
+		for {
+			if _, err := io.ReadFull(c, buf); err != nil {
+				if err == io.EOF {
+					break
+				}
+				t.Errorf("unexpected Read error: %v", err)
+			}
+
+			v := binary.LittleEndian.Uint64(buf)
+			binary.LittleEndian.PutUint64(buf, v+1)
+			if prev != 0 && prev+2 != v {
+				t.Errorf("mismatching value: got %d, want %d", v, prev+2)
+			}
+			prev = v
+			if v == 1000 {
+				break
+			}
+
+			if _, err := c.Write(buf); err != nil {
+				t.Errorf("unexpected Write error: %v", err)
+				break
+			}
+		}
+		if err := c.Close(); err != nil {
+			t.Errorf("unexpected Close error: %v", err)
+		}
+	}
+
+	wg.Add(2)
+	go pingPonger(c1)
+	go pingPonger(c2)
+
+	// Start off the chain reaction.
+	if _, err := c1.Write(make([]byte, 8)); err != nil {
+		t.Errorf("unexpected c1.Write error: %v", err)
+	}
+}
+
+// testRacyRead tests that it is safe to mutate the input Read buffer
+// immediately after cancelation has occurred.
+func testRacyRead(t *testing.T, c1, c2 net.Conn) {
+	go chunkedCopy(c2, rand.New(rand.NewSource(0)))
+
+	var wg sync.WaitGroup
+	defer wg.Wait()
+
+	c1.SetReadDeadline(time.Now().Add(time.Millisecond))
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+
+			b1 := make([]byte, 1024)
+			b2 := make([]byte, 1024)
+			for j := 0; j < 100; j++ {
+				_, err := c1.Read(b1)
+				copy(b1, b2) // Mutate b1 to trigger potential race
+				if err != nil {
+					checkForTimeoutError(t, err)
+					c1.SetReadDeadline(time.Now().Add(time.Millisecond))
+				}
+			}
+		}()
+	}
+}
+
+// testRacyWrite tests that it is safe to mutate the input Write buffer
+// immediately after cancelation has occurred.
+func testRacyWrite(t *testing.T, c1, c2 net.Conn) {
+	go chunkedCopy(ioutil.Discard, c2)
+
+	var wg sync.WaitGroup
+	defer wg.Wait()
+
+	c1.SetWriteDeadline(time.Now().Add(time.Millisecond))
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+
+			b1 := make([]byte, 1024)
+			b2 := make([]byte, 1024)
+			for j := 0; j < 100; j++ {
+				_, err := c1.Write(b1)
+				copy(b1, b2) // Mutate b1 to trigger potential race
+				if err != nil {
+					checkForTimeoutError(t, err)
+					c1.SetWriteDeadline(time.Now().Add(time.Millisecond))
+				}
+			}
+		}()
+	}
+}
+
+// testReadTimeout tests that Read timeouts do not affect Write.
+func testReadTimeout(t *testing.T, c1, c2 net.Conn) {
+	go chunkedCopy(ioutil.Discard, c2)
+
+	c1.SetReadDeadline(aLongTimeAgo)
+	_, err := c1.Read(make([]byte, 1024))
+	checkForTimeoutError(t, err)
+	if _, err := c1.Write(make([]byte, 1024)); err != nil {
+		t.Errorf("unexpected Write error: %v", err)
+	}
+}
+
+// testWriteTimeout tests that Write timeouts do not affect Read.
+func testWriteTimeout(t *testing.T, c1, c2 net.Conn) {
+	go chunkedCopy(c2, rand.New(rand.NewSource(0)))
+
+	c1.SetWriteDeadline(aLongTimeAgo)
+	_, err := c1.Write(make([]byte, 1024))
+	checkForTimeoutError(t, err)
+	if _, err := c1.Read(make([]byte, 1024)); err != nil {
+		t.Errorf("unexpected Read error: %v", err)
+	}
+}
+
+// testPastTimeout tests that a deadline set in the past immediately times out
+// Read and Write requests.
+func testPastTimeout(t *testing.T, c1, c2 net.Conn) {
+	go chunkedCopy(c2, c2)
+
+	testRoundtrip(t, c1)
+
+	c1.SetDeadline(aLongTimeAgo)
+	n, err := c1.Write(make([]byte, 1024))
+	if n != 0 {
+		t.Errorf("unexpected Write count: got %d, want 0", n)
+	}
+	checkForTimeoutError(t, err)
+	n, err = c1.Read(make([]byte, 1024))
+	if n != 0 {
+		t.Errorf("unexpected Read count: got %d, want 0", n)
+	}
+	checkForTimeoutError(t, err)
+
+	testRoundtrip(t, c1)
+}
+
+// testPresentTimeout tests that a deadline set while there are pending
+// Read and Write operations immediately times out those operations.
+func testPresentTimeout(t *testing.T, c1, c2 net.Conn) {
+	var wg sync.WaitGroup
+	defer wg.Wait()
+	wg.Add(3)
+
+	deadlineSet := make(chan bool, 1)
+	go func() {
+		defer wg.Done()
+		time.Sleep(100 * time.Millisecond)
+		deadlineSet <- true
+		c1.SetReadDeadline(aLongTimeAgo)
+		c1.SetWriteDeadline(aLongTimeAgo)
+	}()
+	go func() {
+		defer wg.Done()
+		n, err := c1.Read(make([]byte, 1024))
+		if n != 0 {
+			t.Errorf("unexpected Read count: got %d, want 0", n)
+		}
+		checkForTimeoutError(t, err)
+		if len(deadlineSet) == 0 {
+			t.Error("Read timed out before deadline is set")
+		}
+	}()
+	go func() {
+		defer wg.Done()
+		var err error
+		for err == nil {
+			_, err = c1.Write(make([]byte, 1024))
+		}
+		checkForTimeoutError(t, err)
+		if len(deadlineSet) == 0 {
+			t.Error("Write timed out before deadline is set")
+		}
+	}()
+}
+
+// testFutureTimeout tests that a future deadline will eventually time out
+// Read and Write operations.
+func testFutureTimeout(t *testing.T, c1, c2 net.Conn) {
+	var wg sync.WaitGroup
+	wg.Add(2)
+
+	c1.SetDeadline(time.Now().Add(100 * time.Millisecond))
+	go func() {
+		defer wg.Done()
+		_, err := c1.Read(make([]byte, 1024))
+		checkForTimeoutError(t, err)
+	}()
+	go func() {
+		defer wg.Done()
+		var err error
+		for err == nil {
+			_, err = c1.Write(make([]byte, 1024))
+		}
+		checkForTimeoutError(t, err)
+	}()
+	wg.Wait()
+
+	go chunkedCopy(c2, c2)
+	resyncConn(t, c1)
+	testRoundtrip(t, c1)
+}
+
+// testCloseTimeout tests that calling Close immediately times out pending
+// Read and Write operations.
+func testCloseTimeout(t *testing.T, c1, c2 net.Conn) {
+	go chunkedCopy(c2, c2)
+
+	var wg sync.WaitGroup
+	defer wg.Wait()
+	wg.Add(3)
+
+	// Test for cancelation upon connection closure.
+	c1.SetDeadline(neverTimeout)
+	go func() {
+		defer wg.Done()
+		time.Sleep(100 * time.Millisecond)
+		c1.Close()
+	}()
+	go func() {
+		defer wg.Done()
+		var err error
+		buf := make([]byte, 1024)
+		for err == nil {
+			_, err = c1.Read(buf)
+		}
+	}()
+	go func() {
+		defer wg.Done()
+		var err error
+		buf := make([]byte, 1024)
+		for err == nil {
+			_, err = c1.Write(buf)
+		}
+	}()
+}
+
+// testConcurrentMethods tests that the methods of net.Conn can safely
+// be called concurrently.
+func testConcurrentMethods(t *testing.T, c1, c2 net.Conn) {
+	if runtime.GOOS == "plan9" {
+		t.Skip("skipping on plan9; see https://golang.org/issue/20489")
+	}
+	go chunkedCopy(c2, c2)
+
+	// The results of the calls may be nonsensical, but this should
+	// not trigger a race detector warning.
+	var wg sync.WaitGroup
+	for i := 0; i < 100; i++ {
+		wg.Add(7)
+		go func() {
+			defer wg.Done()
+			c1.Read(make([]byte, 1024))
+		}()
+		go func() {
+			defer wg.Done()
+			c1.Write(make([]byte, 1024))
+		}()
+		go func() {
+			defer wg.Done()
+			c1.SetDeadline(time.Now().Add(10 * time.Millisecond))
+		}()
+		go func() {
+			defer wg.Done()
+			c1.SetReadDeadline(aLongTimeAgo)
+		}()
+		go func() {
+			defer wg.Done()
+			c1.SetWriteDeadline(aLongTimeAgo)
+		}()
+		go func() {
+			defer wg.Done()
+			c1.LocalAddr()
+		}()
+		go func() {
+			defer wg.Done()
+			c1.RemoteAddr()
+		}()
+	}
+	wg.Wait() // At worst, the deadline is set 10ms into the future
+
+	resyncConn(t, c1)
+	testRoundtrip(t, c1)
+}
+
+// checkForTimeoutError checks that the error satisfies the Error interface
+// and that Timeout returns true.
+func checkForTimeoutError(t *testing.T, err error) {
+	if nerr, ok := err.(net.Error); ok {
+		if !nerr.Timeout() {
+			t.Errorf("err.Timeout() = false, want true")
+		}
+	} else {
+		t.Errorf("got %T, want net.Error", err)
+	}
+}
+
+// testRoundtrip writes something into c and reads it back.
+// It assumes that everything written into c is echoed back to itself.
+func testRoundtrip(t *testing.T, c net.Conn) {
+	if err := c.SetDeadline(neverTimeout); err != nil {
+		t.Errorf("roundtrip SetDeadline error: %v", err)
+	}
+
+	const s = "Hello, world!"
+	buf := []byte(s)
+	if _, err := c.Write(buf); err != nil {
+		t.Errorf("roundtrip Write error: %v", err)
+	}
+	if _, err := io.ReadFull(c, buf); err != nil {
+		t.Errorf("roundtrip Read error: %v", err)
+	}
+	if string(buf) != s {
+		t.Errorf("roundtrip data mismatch: got %q, want %q", buf, s)
+	}
+}
+
+// resyncConn resynchronizes the connection into a sane state.
+// It assumes that everything written into c is echoed back to itself.
+// It assumes that 0xff is not currently on the wire or in the read buffer.
+func resyncConn(t *testing.T, c net.Conn) {
+	c.SetDeadline(neverTimeout)
+	errCh := make(chan error)
+	go func() {
+		_, err := c.Write([]byte{0xff})
+		errCh <- err
+	}()
+	buf := make([]byte, 1024)
+	for {
+		n, err := c.Read(buf)
+		if n > 0 && bytes.IndexByte(buf[:n], 0xff) == n-1 {
+			break
+		}
+		if err != nil {
+			t.Errorf("unexpected Read error: %v", err)
+			break
+		}
+	}
+	if err := <-errCh; err != nil {
+		t.Errorf("unexpected Write error: %v", err)
+	}
+}
+
+// chunkedCopy copies from r to w in fixed-width chunks to avoid
+// causing a Write that exceeds the maximum packet size for packet-based
+// connections like "unixpacket".
+// We assume that the maximum packet size is at least 1024.
+func chunkedCopy(w io.Writer, r io.Reader) error {
+	b := make([]byte, 1024)
+	_, err := io.CopyBuffer(struct{ io.Writer }{w}, struct{ io.Reader }{r}, b)
+	return err
+}
diff --git a/libgo/go/golang_org/x/net/nettest/conntest_go16.go b/libgo/go/golang_org/x/net/nettest/conntest_go16.go
new file mode 100644
index 0000000..4cbf48e
--- /dev/null
+++ b/libgo/go/golang_org/x/net/nettest/conntest_go16.go
@@ -0,0 +1,24 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.7
+
+package nettest
+
+import "testing"
+
+func testConn(t *testing.T, mp MakePipe) {
+	// Avoid using subtests on Go 1.6 and below.
+	timeoutWrapper(t, mp, testBasicIO)
+	timeoutWrapper(t, mp, testPingPong)
+	timeoutWrapper(t, mp, testRacyRead)
+	timeoutWrapper(t, mp, testRacyWrite)
+	timeoutWrapper(t, mp, testReadTimeout)
+	timeoutWrapper(t, mp, testWriteTimeout)
+	timeoutWrapper(t, mp, testPastTimeout)
+	timeoutWrapper(t, mp, testPresentTimeout)
+	timeoutWrapper(t, mp, testFutureTimeout)
+	timeoutWrapper(t, mp, testCloseTimeout)
+	timeoutWrapper(t, mp, testConcurrentMethods)
+}
diff --git a/libgo/go/golang_org/x/net/nettest/conntest_go17.go b/libgo/go/golang_org/x/net/nettest/conntest_go17.go
new file mode 100644
index 0000000..fa039f0
--- /dev/null
+++ b/libgo/go/golang_org/x/net/nettest/conntest_go17.go
@@ -0,0 +1,24 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.7
+
+package nettest
+
+import "testing"
+
+func testConn(t *testing.T, mp MakePipe) {
+	// Use subtests on Go 1.7 and above since it is better organized.
+	t.Run("BasicIO", func(t *testing.T) { timeoutWrapper(t, mp, testBasicIO) })
+	t.Run("PingPong", func(t *testing.T) { timeoutWrapper(t, mp, testPingPong) })
+	t.Run("RacyRead", func(t *testing.T) { timeoutWrapper(t, mp, testRacyRead) })
+	t.Run("RacyWrite", func(t *testing.T) { timeoutWrapper(t, mp, testRacyWrite) })
+	t.Run("ReadTimeout", func(t *testing.T) { timeoutWrapper(t, mp, testReadTimeout) })
+	t.Run("WriteTimeout", func(t *testing.T) { timeoutWrapper(t, mp, testWriteTimeout) })
+	t.Run("PastTimeout", func(t *testing.T) { timeoutWrapper(t, mp, testPastTimeout) })
+	t.Run("PresentTimeout", func(t *testing.T) { timeoutWrapper(t, mp, testPresentTimeout) })
+	t.Run("FutureTimeout", func(t *testing.T) { timeoutWrapper(t, mp, testFutureTimeout) })
+	t.Run("CloseTimeout", func(t *testing.T) { timeoutWrapper(t, mp, testCloseTimeout) })
+	t.Run("ConcurrentMethods", func(t *testing.T) { timeoutWrapper(t, mp, testConcurrentMethods) })
+}
diff --git a/libgo/go/golang_org/x/net/nettest/conntest_test.go b/libgo/go/golang_org/x/net/nettest/conntest_test.go
new file mode 100644
index 0000000..23bd69f
--- /dev/null
+++ b/libgo/go/golang_org/x/net/nettest/conntest_test.go
@@ -0,0 +1,126 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.8
+
+package nettest
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net"
+	"os"
+	"runtime"
+	"testing"
+)
+
+// testUnixAddr uses ioutil.TempFile to get a name that is unique.
+// It also uses /tmp directory in case it is prohibited to create UNIX
+// sockets in TMPDIR.
+func testUnixAddr() string {
+	f, err := ioutil.TempFile("", "go-nettest")
+	if err != nil {
+		panic(err)
+	}
+	addr := f.Name()
+	f.Close()
+	os.Remove(addr)
+	return addr
+}
+
+// testableNetwork reports whether network is testable on the current
+// platform configuration.
+// This is based on logic from standard library's net/platform_test.go.
+func testableNetwork(network string) bool {
+	switch network {
+	case "unix":
+		switch runtime.GOOS {
+		case "android", "nacl", "plan9", "windows":
+			return false
+		}
+		if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
+			return false
+		}
+	case "unixpacket":
+		switch runtime.GOOS {
+		case "android", "darwin", "nacl", "plan9", "windows", "freebsd":
+			return false
+		}
+	}
+	return true
+}
+
+func newLocalListener(network string) (net.Listener, error) {
+	switch network {
+	case "tcp":
+		ln, err := net.Listen("tcp", "127.0.0.1:0")
+		if err != nil {
+			ln, err = net.Listen("tcp6", "[::1]:0")
+		}
+		return ln, err
+	case "unix", "unixpacket":
+		return net.Listen(network, testUnixAddr())
+	}
+	return nil, fmt.Errorf("%s is not supported", network)
+}
+
+func TestTestConn(t *testing.T) {
+	tests := []struct{ name, network string }{
+		{"TCP", "tcp"},
+		{"UnixPipe", "unix"},
+		{"UnixPacketPipe", "unixpacket"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if !testableNetwork(tt.network) {
+				t.Skipf("not supported on %s", runtime.GOOS)
+			}
+
+			mp := func() (c1, c2 net.Conn, stop func(), err error) {
+				ln, err := newLocalListener(tt.network)
+				if err != nil {
+					return nil, nil, nil, err
+				}
+
+				// Start a connection between two endpoints.
+				var err1, err2 error
+				done := make(chan bool)
+				go func() {
+					c2, err2 = ln.Accept()
+					close(done)
+				}()
+				c1, err1 = net.Dial(ln.Addr().Network(), ln.Addr().String())
+				<-done
+
+				stop = func() {
+					if err1 == nil {
+						c1.Close()
+					}
+					if err2 == nil {
+						c2.Close()
+					}
+					ln.Close()
+					switch tt.network {
+					case "unix", "unixpacket":
+						os.Remove(ln.Addr().String())
+					}
+				}
+
+				switch {
+				case err1 != nil:
+					stop()
+					return nil, nil, nil, err1
+				case err2 != nil:
+					stop()
+					return nil, nil, nil, err2
+				default:
+					return c1, c2, stop, nil
+				}
+			}
+
+			TestConn(t, mp)
+		})
+	}
+}
diff --git a/libgo/go/golang_org/x/net/proxy/direct.go b/libgo/go/golang_org/x/net/proxy/direct.go
new file mode 100644
index 0000000..4c5ad88
--- /dev/null
+++ b/libgo/go/golang_org/x/net/proxy/direct.go
@@ -0,0 +1,18 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package proxy
+
+import (
+	"net"
+)
+
+type direct struct{}
+
+// Direct is a direct proxy: one that makes network connections directly.
+var Direct = direct{}
+
+func (direct) Dial(network, addr string) (net.Conn, error) {
+	return net.Dial(network, addr)
+}
diff --git a/libgo/go/golang_org/x/net/proxy/per_host.go b/libgo/go/golang_org/x/net/proxy/per_host.go
new file mode 100644
index 0000000..f540b19
--- /dev/null
+++ b/libgo/go/golang_org/x/net/proxy/per_host.go
@@ -0,0 +1,140 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package proxy
+
+import (
+	"net"
+	"strings"
+)
+
+// A PerHost directs connections to a default Dialer unless the hostname
+// requested matches one of a number of exceptions.
+type PerHost struct {
+	def, bypass Dialer
+
+	bypassNetworks []*net.IPNet
+	bypassIPs      []net.IP
+	bypassZones    []string
+	bypassHosts    []string
+}
+
+// NewPerHost returns a PerHost Dialer that directs connections to either
+// defaultDialer or bypass, depending on whether the connection matches one of
+// the configured rules.
+func NewPerHost(defaultDialer, bypass Dialer) *PerHost {
+	return &PerHost{
+		def:    defaultDialer,
+		bypass: bypass,
+	}
+}
+
+// Dial connects to the address addr on the given network through either
+// defaultDialer or bypass.
+func (p *PerHost) Dial(network, addr string) (c net.Conn, err error) {
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+
+	return p.dialerForRequest(host).Dial(network, addr)
+}
+
+func (p *PerHost) dialerForRequest(host string) Dialer {
+	if ip := net.ParseIP(host); ip != nil {
+		for _, net := range p.bypassNetworks {
+			if net.Contains(ip) {
+				return p.bypass
+			}
+		}
+		for _, bypassIP := range p.bypassIPs {
+			if bypassIP.Equal(ip) {
+				return p.bypass
+			}
+		}
+		return p.def
+	}
+
+	for _, zone := range p.bypassZones {
+		if strings.HasSuffix(host, zone) {
+			return p.bypass
+		}
+		if host == zone[1:] {
+			// For a zone "example.com", we match "example.com"
+			// too.
+			return p.bypass
+		}
+	}
+	for _, bypassHost := range p.bypassHosts {
+		if bypassHost == host {
+			return p.bypass
+		}
+	}
+	return p.def
+}
+
+// AddFromString parses a string that contains comma-separated values
+// specifying hosts that should use the bypass proxy. Each value is either an
+// IP address, a CIDR range, a zone (*.example.com) or a hostname
+// (localhost). A best effort is made to parse the string and errors are
+// ignored.
+func (p *PerHost) AddFromString(s string) {
+	hosts := strings.Split(s, ",")
+	for _, host := range hosts {
+		host = strings.TrimSpace(host)
+		if len(host) == 0 {
+			continue
+		}
+		if strings.Contains(host, "/") {
+			// We assume that it's a CIDR address like 127.0.0.0/8
+			if _, net, err := net.ParseCIDR(host); err == nil {
+				p.AddNetwork(net)
+			}
+			continue
+		}
+		if ip := net.ParseIP(host); ip != nil {
+			p.AddIP(ip)
+			continue
+		}
+		if strings.HasPrefix(host, "*.") {
+			p.AddZone(host[1:])
+			continue
+		}
+		p.AddHost(host)
+	}
+}
+
+// AddIP specifies an IP address that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match an IP.
+func (p *PerHost) AddIP(ip net.IP) {
+	p.bypassIPs = append(p.bypassIPs, ip)
+}
+
+// AddNetwork specifies an IP range that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match.
+func (p *PerHost) AddNetwork(net *net.IPNet) {
+	p.bypassNetworks = append(p.bypassNetworks, net)
+}
+
+// AddZone specifies a DNS suffix that will use the bypass proxy. A zone of
+// "example.com" matches "example.com" and all of its subdomains.
+func (p *PerHost) AddZone(zone string) {
+	if strings.HasSuffix(zone, ".") {
+		zone = zone[:len(zone)-1]
+	}
+	if !strings.HasPrefix(zone, ".") {
+		zone = "." + zone
+	}
+	p.bypassZones = append(p.bypassZones, zone)
+}
+
+// AddHost specifies a hostname that will use the bypass proxy.
+func (p *PerHost) AddHost(host string) {
+	if strings.HasSuffix(host, ".") {
+		host = host[:len(host)-1]
+	}
+	p.bypassHosts = append(p.bypassHosts, host)
+}
diff --git a/libgo/go/golang_org/x/net/proxy/per_host_test.go b/libgo/go/golang_org/x/net/proxy/per_host_test.go
new file mode 100644
index 0000000..a7d8095
--- /dev/null
+++ b/libgo/go/golang_org/x/net/proxy/per_host_test.go
@@ -0,0 +1,55 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package proxy
+
+import (
+	"errors"
+	"net"
+	"reflect"
+	"testing"
+)
+
+type recordingProxy struct {
+	addrs []string
+}
+
+func (r *recordingProxy) Dial(network, addr string) (net.Conn, error) {
+	r.addrs = append(r.addrs, addr)
+	return nil, errors.New("recordingProxy")
+}
+
+func TestPerHost(t *testing.T) {
+	var def, bypass recordingProxy
+	perHost := NewPerHost(&def, &bypass)
+	perHost.AddFromString("localhost,*.zone,127.0.0.1,10.0.0.1/8,1000::/16")
+
+	expectedDef := []string{
+		"example.com:123",
+		"1.2.3.4:123",
+		"[1001::]:123",
+	}
+	expectedBypass := []string{
+		"localhost:123",
+		"zone:123",
+		"foo.zone:123",
+		"127.0.0.1:123",
+		"10.1.2.3:123",
+		"[1000::]:123",
+	}
+
+	for _, addr := range expectedDef {
+		perHost.Dial("tcp", addr)
+	}
+	for _, addr := range expectedBypass {
+		perHost.Dial("tcp", addr)
+	}
+
+	if !reflect.DeepEqual(expectedDef, def.addrs) {
+		t.Errorf("Hosts which went to the default proxy didn't match. Got %v, want %v", def.addrs, expectedDef)
+	}
+	if !reflect.DeepEqual(expectedBypass, bypass.addrs) {
+		t.Errorf("Hosts which went to the bypass proxy didn't match. Got %v, want %v", bypass.addrs, expectedBypass)
+	}
+}
diff --git a/libgo/go/golang_org/x/net/proxy/proxy.go b/libgo/go/golang_org/x/net/proxy/proxy.go
new file mode 100644
index 0000000..78a8b7b
--- /dev/null
+++ b/libgo/go/golang_org/x/net/proxy/proxy.go
@@ -0,0 +1,94 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package proxy provides support for a variety of protocols to proxy network
+// data.
+package proxy // import "golang.org/x/net/proxy"
+
+import (
+	"errors"
+	"net"
+	"net/url"
+	"os"
+)
+
+// A Dialer is a means to establish a connection.
+type Dialer interface {
+	// Dial connects to the given address via the proxy.
+	Dial(network, addr string) (c net.Conn, err error)
+}
+
+// Auth contains authentication parameters that specific Dialers may require.
+type Auth struct {
+	User, Password string
+}
+
+// FromEnvironment returns the dialer specified by the proxy related variables in
+// the environment.
+func FromEnvironment() Dialer {
+	allProxy := os.Getenv("all_proxy")
+	if len(allProxy) == 0 {
+		return Direct
+	}
+
+	proxyURL, err := url.Parse(allProxy)
+	if err != nil {
+		return Direct
+	}
+	proxy, err := FromURL(proxyURL, Direct)
+	if err != nil {
+		return Direct
+	}
+
+	noProxy := os.Getenv("no_proxy")
+	if len(noProxy) == 0 {
+		return proxy
+	}
+
+	perHost := NewPerHost(proxy, Direct)
+	perHost.AddFromString(noProxy)
+	return perHost
+}
+
+// proxySchemes is a map from URL schemes to a function that creates a Dialer
+// from a URL with such a scheme.
+var proxySchemes map[string]func(*url.URL, Dialer) (Dialer, error)
+
+// RegisterDialerType takes a URL scheme and a function to generate Dialers from
+// a URL with that scheme and a forwarding Dialer. Registered schemes are used
+// by FromURL.
+func RegisterDialerType(scheme string, f func(*url.URL, Dialer) (Dialer, error)) {
+	if proxySchemes == nil {
+		proxySchemes = make(map[string]func(*url.URL, Dialer) (Dialer, error))
+	}
+	proxySchemes[scheme] = f
+}
+
+// FromURL returns a Dialer given a URL specification and an underlying
+// Dialer for it to make network requests.
+func FromURL(u *url.URL, forward Dialer) (Dialer, error) {
+	var auth *Auth
+	if u.User != nil {
+		auth = new(Auth)
+		auth.User = u.User.Username()
+		if p, ok := u.User.Password(); ok {
+			auth.Password = p
+		}
+	}
+
+	switch u.Scheme {
+	case "socks5":
+		return SOCKS5("tcp", u.Host, auth, forward)
+	}
+
+	// If the scheme doesn't match any of the built-in schemes, see if it
+	// was registered by another package.
+	if proxySchemes != nil {
+		if f, ok := proxySchemes[u.Scheme]; ok {
+			return f(u, forward)
+		}
+	}
+
+	return nil, errors.New("proxy: unknown scheme: " + u.Scheme)
+}
diff --git a/libgo/go/golang_org/x/net/proxy/proxy_test.go b/libgo/go/golang_org/x/net/proxy/proxy_test.go
new file mode 100644
index 0000000..c19a5c0
--- /dev/null
+++ b/libgo/go/golang_org/x/net/proxy/proxy_test.go
@@ -0,0 +1,142 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package proxy
+
+import (
+	"io"
+	"net"
+	"net/url"
+	"strconv"
+	"sync"
+	"testing"
+)
+
+func TestFromURL(t *testing.T) {
+	endSystem, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("net.Listen failed: %v", err)
+	}
+	defer endSystem.Close()
+	gateway, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("net.Listen failed: %v", err)
+	}
+	defer gateway.Close()
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go socks5Gateway(t, gateway, endSystem, socks5Domain, &wg)
+
+	url, err := url.Parse("socks5://user:password@" + gateway.Addr().String())
+	if err != nil {
+		t.Fatalf("url.Parse failed: %v", err)
+	}
+	proxy, err := FromURL(url, Direct)
+	if err != nil {
+		t.Fatalf("FromURL failed: %v", err)
+	}
+	_, port, err := net.SplitHostPort(endSystem.Addr().String())
+	if err != nil {
+		t.Fatalf("net.SplitHostPort failed: %v", err)
+	}
+	if c, err := proxy.Dial("tcp", "localhost:"+port); err != nil {
+		t.Fatalf("FromURL.Dial failed: %v", err)
+	} else {
+		c.Close()
+	}
+
+	wg.Wait()
+}
+
+func TestSOCKS5(t *testing.T) {
+	endSystem, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("net.Listen failed: %v", err)
+	}
+	defer endSystem.Close()
+	gateway, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("net.Listen failed: %v", err)
+	}
+	defer gateway.Close()
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go socks5Gateway(t, gateway, endSystem, socks5IP4, &wg)
+
+	proxy, err := SOCKS5("tcp", gateway.Addr().String(), nil, Direct)
+	if err != nil {
+		t.Fatalf("SOCKS5 failed: %v", err)
+	}
+	if c, err := proxy.Dial("tcp", endSystem.Addr().String()); err != nil {
+		t.Fatalf("SOCKS5.Dial failed: %v", err)
+	} else {
+		c.Close()
+	}
+
+	wg.Wait()
+}
+
+func socks5Gateway(t *testing.T, gateway, endSystem net.Listener, typ byte, wg *sync.WaitGroup) {
+	defer wg.Done()
+
+	c, err := gateway.Accept()
+	if err != nil {
+		t.Errorf("net.Listener.Accept failed: %v", err)
+		return
+	}
+	defer c.Close()
+
+	b := make([]byte, 32)
+	var n int
+	if typ == socks5Domain {
+		n = 4
+	} else {
+		n = 3
+	}
+	if _, err := io.ReadFull(c, b[:n]); err != nil {
+		t.Errorf("io.ReadFull failed: %v", err)
+		return
+	}
+	if _, err := c.Write([]byte{socks5Version, socks5AuthNone}); err != nil {
+		t.Errorf("net.Conn.Write failed: %v", err)
+		return
+	}
+	if typ == socks5Domain {
+		n = 16
+	} else {
+		n = 10
+	}
+	if _, err := io.ReadFull(c, b[:n]); err != nil {
+		t.Errorf("io.ReadFull failed: %v", err)
+		return
+	}
+	if b[0] != socks5Version || b[1] != socks5Connect || b[2] != 0x00 || b[3] != typ {
+		t.Errorf("got an unexpected packet: %#02x %#02x %#02x %#02x", b[0], b[1], b[2], b[3])
+		return
+	}
+	if typ == socks5Domain {
+		copy(b[:5], []byte{socks5Version, 0x00, 0x00, socks5Domain, 9})
+		b = append(b, []byte("localhost")...)
+	} else {
+		copy(b[:4], []byte{socks5Version, 0x00, 0x00, socks5IP4})
+	}
+	host, port, err := net.SplitHostPort(endSystem.Addr().String())
+	if err != nil {
+		t.Errorf("net.SplitHostPort failed: %v", err)
+		return
+	}
+	b = append(b, []byte(net.ParseIP(host).To4())...)
+	p, err := strconv.Atoi(port)
+	if err != nil {
+		t.Errorf("strconv.Atoi failed: %v", err)
+		return
+	}
+	b = append(b, []byte{byte(p >> 8), byte(p)}...)
+	if _, err := c.Write(b); err != nil {
+		t.Errorf("net.Conn.Write failed: %v", err)
+		return
+	}
+}
diff --git a/libgo/go/golang_org/x/net/proxy/socks5.go b/libgo/go/golang_org/x/net/proxy/socks5.go
new file mode 100644
index 0000000..973f57f
--- /dev/null
+++ b/libgo/go/golang_org/x/net/proxy/socks5.go
@@ -0,0 +1,213 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package proxy
+
+import (
+	"errors"
+	"io"
+	"net"
+	"strconv"
+)
+
+// SOCKS5 returns a Dialer that makes SOCKSv5 connections to the given address
+// with an optional username and password. See RFC 1928.
+func SOCKS5(network, addr string, auth *Auth, forward Dialer) (Dialer, error) {
+	s := &socks5{
+		network: network,
+		addr:    addr,
+		forward: forward,
+	}
+	if auth != nil {
+		s.user = auth.User
+		s.password = auth.Password
+	}
+
+	return s, nil
+}
+
+type socks5 struct {
+	user, password string
+	network, addr  string
+	forward        Dialer
+}
+
+const socks5Version = 5
+
+const (
+	socks5AuthNone     = 0
+	socks5AuthPassword = 2
+)
+
+const socks5Connect = 1
+
+const (
+	socks5IP4    = 1
+	socks5Domain = 3
+	socks5IP6    = 4
+)
+
+var socks5Errors = []string{
+	"",
+	"general failure",
+	"connection forbidden",
+	"network unreachable",
+	"host unreachable",
+	"connection refused",
+	"TTL expired",
+	"command not supported",
+	"address type not supported",
+}
+
+// Dial connects to the address addr on the network net via the SOCKS5 proxy.
+func (s *socks5) Dial(network, addr string) (net.Conn, error) {
+	switch network {
+	case "tcp", "tcp6", "tcp4":
+	default:
+		return nil, errors.New("proxy: no support for SOCKS5 proxy connections of type " + network)
+	}
+
+	conn, err := s.forward.Dial(s.network, s.addr)
+	if err != nil {
+		return nil, err
+	}
+	if err := s.connect(conn, addr); err != nil {
+		conn.Close()
+		return nil, err
+	}
+	return conn, nil
+}
+
+// connect takes an existing connection to a socks5 proxy server,
+// and commands the server to extend that connection to target,
+// which must be a canonical address with a host and port.
+func (s *socks5) connect(conn net.Conn, target string) error {
+	host, portStr, err := net.SplitHostPort(target)
+	if err != nil {
+		return err
+	}
+
+	port, err := strconv.Atoi(portStr)
+	if err != nil {
+		return errors.New("proxy: failed to parse port number: " + portStr)
+	}
+	if port < 1 || port > 0xffff {
+		return errors.New("proxy: port number out of range: " + portStr)
+	}
+
+	// the size here is just an estimate
+	buf := make([]byte, 0, 6+len(host))
+
+	buf = append(buf, socks5Version)
+	if len(s.user) > 0 && len(s.user) < 256 && len(s.password) < 256 {
+		buf = append(buf, 2 /* num auth methods */, socks5AuthNone, socks5AuthPassword)
+	} else {
+		buf = append(buf, 1 /* num auth methods */, socks5AuthNone)
+	}
+
+	if _, err := conn.Write(buf); err != nil {
+		return errors.New("proxy: failed to write greeting to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+		return errors.New("proxy: failed to read greeting from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+	if buf[0] != 5 {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " has unexpected version " + strconv.Itoa(int(buf[0])))
+	}
+	if buf[1] == 0xff {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " requires authentication")
+	}
+
+	if buf[1] == socks5AuthPassword {
+		buf = buf[:0]
+		buf = append(buf, 1 /* password protocol version */)
+		buf = append(buf, uint8(len(s.user)))
+		buf = append(buf, s.user...)
+		buf = append(buf, uint8(len(s.password)))
+		buf = append(buf, s.password...)
+
+		if _, err := conn.Write(buf); err != nil {
+			return errors.New("proxy: failed to write authentication request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+
+		if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+			return errors.New("proxy: failed to read authentication reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+
+		if buf[1] != 0 {
+			return errors.New("proxy: SOCKS5 proxy at " + s.addr + " rejected username/password")
+		}
+	}
+
+	buf = buf[:0]
+	buf = append(buf, socks5Version, socks5Connect, 0 /* reserved */)
+
+	if ip := net.ParseIP(host); ip != nil {
+		if ip4 := ip.To4(); ip4 != nil {
+			buf = append(buf, socks5IP4)
+			ip = ip4
+		} else {
+			buf = append(buf, socks5IP6)
+		}
+		buf = append(buf, ip...)
+	} else {
+		if len(host) > 255 {
+			return errors.New("proxy: destination hostname too long: " + host)
+		}
+		buf = append(buf, socks5Domain)
+		buf = append(buf, byte(len(host)))
+		buf = append(buf, host...)
+	}
+	buf = append(buf, byte(port>>8), byte(port))
+
+	if _, err := conn.Write(buf); err != nil {
+		return errors.New("proxy: failed to write connect request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	if _, err := io.ReadFull(conn, buf[:4]); err != nil {
+		return errors.New("proxy: failed to read connect reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	failure := "unknown error"
+	if int(buf[1]) < len(socks5Errors) {
+		failure = socks5Errors[buf[1]]
+	}
+
+	if len(failure) > 0 {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " failed to connect: " + failure)
+	}
+
+	bytesToDiscard := 0
+	switch buf[3] {
+	case socks5IP4:
+		bytesToDiscard = net.IPv4len
+	case socks5IP6:
+		bytesToDiscard = net.IPv6len
+	case socks5Domain:
+		_, err := io.ReadFull(conn, buf[:1])
+		if err != nil {
+			return errors.New("proxy: failed to read domain length from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+		bytesToDiscard = int(buf[0])
+	default:
+		return errors.New("proxy: got unknown address type " + strconv.Itoa(int(buf[3])) + " from SOCKS5 proxy at " + s.addr)
+	}
+
+	if cap(buf) < bytesToDiscard {
+		buf = make([]byte, bytesToDiscard)
+	} else {
+		buf = buf[:bytesToDiscard]
+	}
+	if _, err := io.ReadFull(conn, buf); err != nil {
+		return errors.New("proxy: failed to read address from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	// Also need to discard the port number
+	if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+		return errors.New("proxy: failed to read port from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	return nil
+}
diff --git a/libgo/go/golang_org/x/net/route/address.go b/libgo/go/golang_org/x/net/route/address.go
index a56909c..e6bfa39 100644
--- a/libgo/go/golang_org/x/net/route/address.go
+++ b/libgo/go/golang_org/x/net/route/address.go
@@ -24,6 +24,39 @@
 // Family implements the Family method of Addr interface.
 func (a *LinkAddr) Family() int { return sysAF_LINK }
 
+func (a *LinkAddr) lenAndSpace() (int, int) {
+	l := 8 + len(a.Name) + len(a.Addr)
+	return l, roundup(l)
+}
+
+func (a *LinkAddr) marshal(b []byte) (int, error) {
+	l, ll := a.lenAndSpace()
+	if len(b) < ll {
+		return 0, errShortBuffer
+	}
+	nlen, alen := len(a.Name), len(a.Addr)
+	if nlen > 255 || alen > 255 {
+		return 0, errInvalidAddr
+	}
+	b[0] = byte(l)
+	b[1] = sysAF_LINK
+	if a.Index > 0 {
+		nativeEndian.PutUint16(b[2:4], uint16(a.Index))
+	}
+	data := b[8:]
+	if nlen > 0 {
+		b[5] = byte(nlen)
+		copy(data[:nlen], a.Addr)
+		data = data[nlen:]
+	}
+	if alen > 0 {
+		b[6] = byte(alen)
+		copy(data[:alen], a.Name)
+		data = data[alen:]
+	}
+	return ll, nil
+}
+
 func parseLinkAddr(b []byte) (Addr, error) {
 	if len(b) < 8 {
 		return nil, errInvalidAddr
@@ -90,6 +123,21 @@
 // Family implements the Family method of Addr interface.
 func (a *Inet4Addr) Family() int { return sysAF_INET }
 
+func (a *Inet4Addr) lenAndSpace() (int, int) {
+	return sizeofSockaddrInet, roundup(sizeofSockaddrInet)
+}
+
+func (a *Inet4Addr) marshal(b []byte) (int, error) {
+	l, ll := a.lenAndSpace()
+	if len(b) < ll {
+		return 0, errShortBuffer
+	}
+	b[0] = byte(l)
+	b[1] = sysAF_INET
+	copy(b[4:8], a.IP[:])
+	return ll, nil
+}
+
 // An Inet6Addr represents an internet address for IPv6.
 type Inet6Addr struct {
 	IP     [16]byte // IP address
@@ -99,18 +147,36 @@
 // Family implements the Family method of Addr interface.
 func (a *Inet6Addr) Family() int { return sysAF_INET6 }
 
+func (a *Inet6Addr) lenAndSpace() (int, int) {
+	return sizeofSockaddrInet6, roundup(sizeofSockaddrInet6)
+}
+
+func (a *Inet6Addr) marshal(b []byte) (int, error) {
+	l, ll := a.lenAndSpace()
+	if len(b) < ll {
+		return 0, errShortBuffer
+	}
+	b[0] = byte(l)
+	b[1] = sysAF_INET6
+	copy(b[8:24], a.IP[:])
+	if a.ZoneID > 0 {
+		nativeEndian.PutUint32(b[24:28], uint32(a.ZoneID))
+	}
+	return ll, nil
+}
+
 // parseInetAddr parses b as an internet address for IPv4 or IPv6.
 func parseInetAddr(af int, b []byte) (Addr, error) {
 	switch af {
 	case sysAF_INET:
-		if len(b) < 16 {
+		if len(b) < sizeofSockaddrInet {
 			return nil, errInvalidAddr
 		}
 		a := &Inet4Addr{}
 		copy(a.IP[:], b[4:8])
 		return a, nil
 	case sysAF_INET6:
-		if len(b) < 28 {
+		if len(b) < sizeofSockaddrInet6 {
 			return nil, errInvalidAddr
 		}
 		a := &Inet6Addr{ZoneID: int(nativeEndian.Uint32(b[24:28]))}
@@ -174,7 +240,7 @@
 		off6 = 8 // offset of in6_addr
 	)
 	switch {
-	case b[0] == 28: // size of sockaddr_in6
+	case b[0] == sizeofSockaddrInet6:
 		a := &Inet6Addr{}
 		copy(a.IP[:], b[off6:off6+16])
 		return int(b[0]), a, nil
@@ -186,7 +252,7 @@
 			copy(a.IP[:], b[l-off6:l])
 		}
 		return int(b[0]), a, nil
-	case b[0] == 16: // size of sockaddr_in
+	case b[0] == sizeofSockaddrInet:
 		a := &Inet4Addr{}
 		copy(a.IP[:], b[off4:off4+4])
 		return int(b[0]), a, nil
@@ -211,6 +277,24 @@
 // Family implements the Family method of Addr interface.
 func (a *DefaultAddr) Family() int { return a.af }
 
+func (a *DefaultAddr) lenAndSpace() (int, int) {
+	l := len(a.Raw)
+	return l, roundup(l)
+}
+
+func (a *DefaultAddr) marshal(b []byte) (int, error) {
+	l, ll := a.lenAndSpace()
+	if len(b) < ll {
+		return 0, errShortBuffer
+	}
+	if l > 255 {
+		return 0, errInvalidAddr
+	}
+	b[1] = byte(l)
+	copy(b[:l], a.Raw)
+	return ll, nil
+}
+
 func parseDefaultAddr(b []byte) (Addr, error) {
 	if len(b) < 2 || len(b) < int(b[0]) {
 		return nil, errInvalidAddr
@@ -219,6 +303,66 @@
 	return a, nil
 }
 
+func addrsSpace(as []Addr) int {
+	var l int
+	for _, a := range as {
+		switch a := a.(type) {
+		case *LinkAddr:
+			_, ll := a.lenAndSpace()
+			l += ll
+		case *Inet4Addr:
+			_, ll := a.lenAndSpace()
+			l += ll
+		case *Inet6Addr:
+			_, ll := a.lenAndSpace()
+			l += ll
+		case *DefaultAddr:
+			_, ll := a.lenAndSpace()
+			l += ll
+		}
+	}
+	return l
+}
+
+// marshalAddrs marshals as and returns a bitmap indicating which
+// address is stored in b.
+func marshalAddrs(b []byte, as []Addr) (uint, error) {
+	var attrs uint
+	for i, a := range as {
+		switch a := a.(type) {
+		case *LinkAddr:
+			l, err := a.marshal(b)
+			if err != nil {
+				return 0, err
+			}
+			b = b[l:]
+			attrs |= 1 << uint(i)
+		case *Inet4Addr:
+			l, err := a.marshal(b)
+			if err != nil {
+				return 0, err
+			}
+			b = b[l:]
+			attrs |= 1 << uint(i)
+		case *Inet6Addr:
+			l, err := a.marshal(b)
+			if err != nil {
+				return 0, err
+			}
+			b = b[l:]
+			attrs |= 1 << uint(i)
+		case *DefaultAddr:
+			l, err := a.marshal(b)
+			if err != nil {
+				return 0, err
+			}
+			b = b[l:]
+			attrs |= 1 << uint(i)
+		}
+	}
+	return attrs, nil
+}
+
 func parseAddrs(attrs uint, fn func(int, []byte) (int, Addr, error), b []byte) ([]Addr, error) {
 	var as [sysRTAX_MAX]Addr
 	af := int(sysAF_UNSPEC)
diff --git a/libgo/go/golang_org/x/net/route/binary.go b/libgo/go/golang_org/x/net/route/binary.go
index 4c56163..6910520 100644
--- a/libgo/go/golang_org/x/net/route/binary.go
+++ b/libgo/go/golang_org/x/net/route/binary.go
@@ -9,7 +9,7 @@
 // This file contains duplicates of encoding/binary package.
 //
 // This package is supposed to be used by the net package of standard
-// library. Therefore a package set used in the package must be the
+// library. Therefore the package set used in the package must be the
 // same as net package.
 
 var (
diff --git a/libgo/go/golang_org/x/net/route/defs_darwin.go b/libgo/go/golang_org/x/net/route/defs_darwin.go
index f452ad1..e771644 100644
--- a/libgo/go/golang_org/x/net/route/defs_darwin.go
+++ b/libgo/go/golang_org/x/net/route/defs_darwin.go
@@ -13,6 +13,8 @@
 #include <net/if.h>
 #include <net/if_dl.h>
 #include <net/route.h>
+
+#include <netinet/in.h>
 */
 import "C"
 
@@ -23,6 +25,8 @@
 	sysAF_LINK   = C.AF_LINK
 	sysAF_INET6  = C.AF_INET6
 
+	sysSOCK_RAW = C.SOCK_RAW
+
 	sysNET_RT_DUMP    = C.NET_RT_DUMP
 	sysNET_RT_FLAGS   = C.NET_RT_FLAGS
 	sysNET_RT_IFLIST  = C.NET_RT_IFLIST
@@ -103,4 +107,8 @@
 	sizeofRtMsghdrDarwin15  = C.sizeof_struct_rt_msghdr
 	sizeofRtMsghdr2Darwin15 = C.sizeof_struct_rt_msghdr2
 	sizeofRtMetricsDarwin15 = C.sizeof_struct_rt_metrics
+
+	sizeofSockaddrStorage = C.sizeof_struct_sockaddr_storage
+	sizeofSockaddrInet    = C.sizeof_struct_sockaddr_in
+	sizeofSockaddrInet6   = C.sizeof_struct_sockaddr_in6
 )
diff --git a/libgo/go/golang_org/x/net/route/defs_dragonfly.go b/libgo/go/golang_org/x/net/route/defs_dragonfly.go
index c737751..dd31de2 100644
--- a/libgo/go/golang_org/x/net/route/defs_dragonfly.go
+++ b/libgo/go/golang_org/x/net/route/defs_dragonfly.go
@@ -13,6 +13,8 @@
 #include <net/if.h>
 #include <net/if_dl.h>
 #include <net/route.h>
+
+#include <netinet/in.h>
 */
 import "C"
 
@@ -23,6 +25,8 @@
 	sysAF_LINK   = C.AF_LINK
 	sysAF_INET6  = C.AF_INET6
 
+	sysSOCK_RAW = C.SOCK_RAW
+
 	sysNET_RT_DUMP   = C.NET_RT_DUMP
 	sysNET_RT_FLAGS  = C.NET_RT_FLAGS
 	sysNET_RT_IFLIST = C.NET_RT_IFLIST
@@ -102,4 +106,8 @@
 
 	sizeofRtMsghdrDragonFlyBSD4  = C.sizeof_struct_rt_msghdr
 	sizeofRtMetricsDragonFlyBSD4 = C.sizeof_struct_rt_metrics
+
+	sizeofSockaddrStorage = C.sizeof_struct_sockaddr_storage
+	sizeofSockaddrInet    = C.sizeof_struct_sockaddr_in
+	sizeofSockaddrInet6   = C.sizeof_struct_sockaddr_in6
 )
diff --git a/libgo/go/golang_org/x/net/route/defs_freebsd.go b/libgo/go/golang_org/x/net/route/defs_freebsd.go
index 8f834e8..d95594d 100644
--- a/libgo/go/golang_org/x/net/route/defs_freebsd.go
+++ b/libgo/go/golang_org/x/net/route/defs_freebsd.go
@@ -14,6 +14,8 @@
 #include <net/if_dl.h>
 #include <net/route.h>
 
+#include <netinet/in.h>
+
 struct if_data_freebsd7 {
 	u_char ifi_type;
 	u_char ifi_physical;
@@ -222,6 +224,8 @@
 	sysAF_LINK   = C.AF_LINK
 	sysAF_INET6  = C.AF_INET6
 
+	sysSOCK_RAW = C.SOCK_RAW
+
 	sysNET_RT_DUMP     = C.NET_RT_DUMP
 	sysNET_RT_FLAGS    = C.NET_RT_FLAGS
 	sysNET_RT_IFLIST   = C.NET_RT_IFLIST
@@ -326,4 +330,8 @@
 	sizeofIfDataFreeBSD9Emu  = C.sizeof_struct_if_data_freebsd9
 	sizeofIfDataFreeBSD10Emu = C.sizeof_struct_if_data_freebsd10
 	sizeofIfDataFreeBSD11Emu = C.sizeof_struct_if_data_freebsd11
+
+	sizeofSockaddrStorage = C.sizeof_struct_sockaddr_storage
+	sizeofSockaddrInet    = C.sizeof_struct_sockaddr_in
+	sizeofSockaddrInet6   = C.sizeof_struct_sockaddr_in6
 )
diff --git a/libgo/go/golang_org/x/net/route/defs_netbsd.go b/libgo/go/golang_org/x/net/route/defs_netbsd.go
index b18d85e..b0abd54 100644
--- a/libgo/go/golang_org/x/net/route/defs_netbsd.go
+++ b/libgo/go/golang_org/x/net/route/defs_netbsd.go
@@ -13,6 +13,8 @@
 #include <net/if.h>
 #include <net/if_dl.h>
 #include <net/route.h>
+
+#include <netinet/in.h>
 */
 import "C"
 
@@ -23,6 +25,8 @@
 	sysAF_LINK   = C.AF_LINK
 	sysAF_INET6  = C.AF_INET6
 
+	sysSOCK_RAW = C.SOCK_RAW
+
 	sysNET_RT_DUMP   = C.NET_RT_DUMP
 	sysNET_RT_FLAGS  = C.NET_RT_FLAGS
 	sysNET_RT_IFLIST = C.NET_RT_IFLIST
@@ -101,4 +105,8 @@
 
 	sizeofRtMsghdrNetBSD7  = C.sizeof_struct_rt_msghdr
 	sizeofRtMetricsNetBSD7 = C.sizeof_struct_rt_metrics
+
+	sizeofSockaddrStorage = C.sizeof_struct_sockaddr_storage
+	sizeofSockaddrInet    = C.sizeof_struct_sockaddr_in
+	sizeofSockaddrInet6   = C.sizeof_struct_sockaddr_in6
 )
diff --git a/libgo/go/golang_org/x/net/route/defs_openbsd.go b/libgo/go/golang_org/x/net/route/defs_openbsd.go
index 5df7a43..0f66d36 100644
--- a/libgo/go/golang_org/x/net/route/defs_openbsd.go
+++ b/libgo/go/golang_org/x/net/route/defs_openbsd.go
@@ -13,6 +13,8 @@
 #include <net/if.h>
 #include <net/if_dl.h>
 #include <net/route.h>
+
+#include <netinet/in.h>
 */
 import "C"
 
@@ -23,6 +25,8 @@
 	sysAF_LINK   = C.AF_LINK
 	sysAF_INET6  = C.AF_INET6
 
+	sysSOCK_RAW = C.SOCK_RAW
+
 	sysNET_RT_DUMP    = C.NET_RT_DUMP
 	sysNET_RT_FLAGS   = C.NET_RT_FLAGS
 	sysNET_RT_IFLIST  = C.NET_RT_IFLIST
@@ -91,3 +95,11 @@
 	sysRTAX_LABEL   = C.RTAX_LABEL
 	sysRTAX_MAX     = C.RTAX_MAX
 )
+
+const (
+	sizeofRtMsghdr = C.sizeof_struct_rt_msghdr
+
+	sizeofSockaddrStorage = C.sizeof_struct_sockaddr_storage
+	sizeofSockaddrInet    = C.sizeof_struct_sockaddr_in
+	sizeofSockaddrInet6   = C.sizeof_struct_sockaddr_in6
+)
diff --git a/libgo/go/golang_org/x/net/route/message.go b/libgo/go/golang_org/x/net/route/message.go
index d7ae0eb..0fa7e09 100644
--- a/libgo/go/golang_org/x/net/route/message.go
+++ b/libgo/go/golang_org/x/net/route/message.go
@@ -7,9 +7,6 @@
 package route
 
 // A Message represents a routing message.
-//
-// Note: This interface will be changed to support Marshal method in
-// future version.
 type Message interface {
 	// Sys returns operating system-specific information.
 	Sys() []Sys
@@ -52,11 +49,10 @@
 			b = b[l:]
 			continue
 		}
-		mtyp := int(b[3])
-		if fn, ok := parseFns[mtyp]; !ok {
+		if w, ok := wireFormats[int(b[3])]; !ok {
 			nskips++
 		} else {
-			m, err := fn(typ, b)
+			m, err := w.parse(typ, b)
 			if err != nil {
 				return nil, err
 			}
diff --git a/libgo/go/golang_org/x/net/route/message_darwin_test.go b/libgo/go/golang_org/x/net/route/message_darwin_test.go
index 3fdd12d..316aa75 100644
--- a/libgo/go/golang_org/x/net/route/message_darwin_test.go
+++ b/libgo/go/golang_org/x/net/route/message_darwin_test.go
@@ -7,21 +7,28 @@
 import "testing"
 
 func TestFetchAndParseRIBOnDarwin(t *testing.T) {
-	for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
-		for _, typ := range []RIBType{sysNET_RT_FLAGS, sysNET_RT_DUMP2, sysNET_RT_IFLIST2} {
-			ms, err := fetchAndParseRIB(af, typ)
+	for _, typ := range []RIBType{sysNET_RT_FLAGS, sysNET_RT_DUMP2, sysNET_RT_IFLIST2} {
+		var lastErr error
+		var ms []Message
+		for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
+			rs, err := fetchAndParseRIB(af, typ)
 			if err != nil {
-				t.Error(err)
+				lastErr = err
 				continue
 			}
-			ss, err := msgs(ms).validate()
-			if err != nil {
-				t.Errorf("%v %d %v", addrFamily(af), typ, err)
-				continue
-			}
-			for _, s := range ss {
-				t.Log(s)
-			}
+			ms = append(ms, rs...)
+		}
+		if len(ms) == 0 && lastErr != nil {
+			t.Error(typ, lastErr)
+			continue
+		}
+		ss, err := msgs(ms).validate()
+		if err != nil {
+			t.Error(typ, err)
+			continue
+		}
+		for _, s := range ss {
+			t.Log(s)
 		}
 	}
 }
diff --git a/libgo/go/golang_org/x/net/route/message_freebsd_test.go b/libgo/go/golang_org/x/net/route/message_freebsd_test.go
index 785c273..db4b567 100644
--- a/libgo/go/golang_org/x/net/route/message_freebsd_test.go
+++ b/libgo/go/golang_org/x/net/route/message_freebsd_test.go
@@ -6,26 +6,32 @@
 
 import (
 	"testing"
-	"time"
 	"unsafe"
 )
 
 func TestFetchAndParseRIBOnFreeBSD(t *testing.T) {
-	for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
-		for _, typ := range []RIBType{sysNET_RT_IFMALIST} {
-			ms, err := fetchAndParseRIB(af, typ)
+	for _, typ := range []RIBType{sysNET_RT_IFMALIST} {
+		var lastErr error
+		var ms []Message
+		for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
+			rs, err := fetchAndParseRIB(af, typ)
 			if err != nil {
-				t.Error(err)
+				lastErr = err
 				continue
 			}
-			ss, err := msgs(ms).validate()
-			if err != nil {
-				t.Errorf("%v %d %v", addrFamily(af), typ, err)
-				continue
-			}
-			for _, s := range ss {
-				t.Log(s)
-			}
+			ms = append(ms, rs...)
+		}
+		if len(ms) == 0 && lastErr != nil {
+			t.Error(typ, lastErr)
+			continue
+		}
+		ss, err := msgs(ms).validate()
+		if err != nil {
+			t.Error(typ, err)
+			continue
+		}
+		for _, s := range ss {
+			t.Log(s)
 		}
 	}
 }
@@ -48,58 +54,38 @@
 		{typ: sysNET_RT_IFLIST},
 		{typ: sysNET_RT_IFLISTL},
 	}
-	for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
+	for i := range tests {
 		var lastErr error
-		for i := 0; i < 3; i++ {
-			for j := range tests {
-				var err error
-				if tests[j].b, err = FetchRIB(af, tests[j].typ, 0); err != nil {
-					lastErr = err
-					time.Sleep(10 * time.Millisecond)
-				}
-			}
-			if lastErr == nil {
-				break
-			}
-		}
-		if lastErr != nil {
-			t.Error(af, lastErr)
-			continue
-		}
-		for i := range tests {
-			var err error
-			if tests[i].msgs, err = ParseRIB(tests[i].typ, tests[i].b); err != nil {
-				lastErr = err
-				t.Error(af, err)
-			}
-		}
-		if lastErr != nil {
-			continue
-		}
-		for i := range tests {
-			var err error
-			tests[i].ss, err = msgs(tests[i].msgs).validate()
+		for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
+			rs, err := fetchAndParseRIB(af, tests[i].typ)
 			if err != nil {
 				lastErr = err
-				t.Error(af, err)
-			}
-			for _, s := range tests[i].ss {
-				t.Log(s)
-			}
-		}
-		if lastErr != nil {
-			continue
-		}
-		for i := len(tests) - 1; i > 0; i-- {
-			if len(tests[i].ss) != len(tests[i-1].ss) {
-				t.Errorf("got %v; want %v", tests[i].ss, tests[i-1].ss)
 				continue
 			}
-			for j, s1 := range tests[i].ss {
-				s0 := tests[i-1].ss[j]
-				if s1 != s0 {
-					t.Errorf("got %s; want %s", s1, s0)
-				}
+			tests[i].msgs = append(tests[i].msgs, rs...)
+		}
+		if len(tests[i].msgs) == 0 && lastErr != nil {
+			t.Error(tests[i].typ, lastErr)
+			continue
+		}
+		tests[i].ss, lastErr = msgs(tests[i].msgs).validate()
+		if lastErr != nil {
+			t.Error(tests[i].typ, lastErr)
+			continue
+		}
+		for _, s := range tests[i].ss {
+			t.Log(s)
+		}
+	}
+	for i := len(tests) - 1; i > 0; i-- {
+		if len(tests[i].ss) != len(tests[i-1].ss) {
+			t.Errorf("got %v; want %v", tests[i].ss, tests[i-1].ss)
+			continue
+		}
+		for j, s1 := range tests[i].ss {
+			s0 := tests[i-1].ss[j]
+			if s1 != s0 {
+				t.Errorf("got %s; want %s", s1, s0)
 			}
 		}
 	}
diff --git a/libgo/go/golang_org/x/net/route/message_test.go b/libgo/go/golang_org/x/net/route/message_test.go
index c0c7c57..e848dab 100644
--- a/libgo/go/golang_org/x/net/route/message_test.go
+++ b/libgo/go/golang_org/x/net/route/message_test.go
@@ -14,30 +14,54 @@
 )
 
 func TestFetchAndParseRIB(t *testing.T) {
-	for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
-		for _, typ := range []RIBType{sysNET_RT_DUMP, sysNET_RT_IFLIST} {
-			ms, err := fetchAndParseRIB(af, typ)
+	for _, typ := range []RIBType{sysNET_RT_DUMP, sysNET_RT_IFLIST} {
+		var lastErr error
+		var ms []Message
+		for _, af := range []int{sysAF_UNSPEC, sysAF_INET, sysAF_INET6} {
+			rs, err := fetchAndParseRIB(af, typ)
 			if err != nil {
-				t.Error(err)
+				lastErr = err
 				continue
 			}
-			ss, err := msgs(ms).validate()
-			if err != nil {
-				t.Errorf("%v %d %v", addrFamily(af), typ, err)
-				continue
-			}
-			for _, s := range ss {
-				t.Log(s)
-			}
+			ms = append(ms, rs...)
+		}
+		if len(ms) == 0 && lastErr != nil {
+			t.Error(typ, lastErr)
+			continue
+		}
+		ss, err := msgs(ms).validate()
+		if err != nil {
+			t.Error(typ, err)
+			continue
+		}
+		for _, s := range ss {
+			t.Log(typ, s)
 		}
 	}
 }
 
+var (
+	rtmonSock int
+	rtmonErr  error
+)
+
+func init() {
+	// We need to keep rtmonSock alive to avoid treading on
+	// recycled socket descriptors.
+	rtmonSock, rtmonErr = syscall.Socket(sysAF_ROUTE, sysSOCK_RAW, sysAF_UNSPEC)
+}
+
+// TestMonitorAndParseRIB leaks a worker goroutine and a socket
+// descriptor but that's intentional.
 func TestMonitorAndParseRIB(t *testing.T) {
 	if testing.Short() || os.Getuid() != 0 {
 		t.Skip("must be root")
 	}
 
+	if rtmonErr != nil {
+		t.Fatal(rtmonErr)
+	}
+
 	// We suppose that using an IPv4 link-local address and the
 	// dot1Q ID for Token Ring and FDDI doesn't harm anyone.
 	pv := &propVirtual{addr: "169.254.0.1", mask: "255.255.255.0"}
@@ -49,16 +73,18 @@
 	}
 	pv.teardown()
 
-	s, err := syscall.Socket(syscall.AF_ROUTE, syscall.SOCK_RAW, syscall.AF_UNSPEC)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer syscall.Close(s)
-
 	go func() {
 		b := make([]byte, os.Getpagesize())
 		for {
-			n, err := syscall.Read(s, b)
+			// There's no easy way to unblock this read
+			// call because the routing message exchange
+			// over routing socket is a connectionless
+			// message-oriented protocol, no control plane
+			// for signaling connectivity, and we cannot
+			// use the net package of standard library due
+			// to the lack of support for routing socket
+			// and circular dependency.
+			n, err := syscall.Read(rtmonSock, b)
 			if err != nil {
 				return
 			}
@@ -116,3 +142,98 @@
 		}
 	}
 }
+
+func TestRouteMessage(t *testing.T) {
+	s, err := syscall.Socket(sysAF_ROUTE, sysSOCK_RAW, sysAF_UNSPEC)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer syscall.Close(s)
+
+	var ms []RouteMessage
+	for _, af := range []int{sysAF_INET, sysAF_INET6} {
+		if _, err := fetchAndParseRIB(af, sysNET_RT_DUMP); err != nil {
+			t.Log(err)
+			continue
+		}
+		switch af {
+		case sysAF_INET:
+			ms = append(ms, []RouteMessage{
+				{
+					Type: sysRTM_GET,
+					Addrs: []Addr{
+						&Inet4Addr{IP: [4]byte{127, 0, 0, 1}},
+						nil,
+						nil,
+						nil,
+						&LinkAddr{},
+						&Inet4Addr{},
+						nil,
+						&Inet4Addr{},
+					},
+				},
+				{
+					Type: sysRTM_GET,
+					Addrs: []Addr{
+						&Inet4Addr{IP: [4]byte{127, 0, 0, 1}},
+					},
+				},
+			}...)
+		case sysAF_INET6:
+			ms = append(ms, []RouteMessage{
+				{
+					Type: sysRTM_GET,
+					Addrs: []Addr{
+						&Inet6Addr{IP: [16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}},
+						nil,
+						nil,
+						nil,
+						&LinkAddr{},
+						&Inet6Addr{},
+						nil,
+						&Inet6Addr{},
+					},
+				},
+				{
+					Type: sysRTM_GET,
+					Addrs: []Addr{
+						&Inet6Addr{IP: [16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}},
+					},
+				},
+			}...)
+		}
+	}
+	for i, m := range ms {
+		m.ID = uintptr(os.Getpid())
+		m.Seq = i + 1
+		wb, err := m.Marshal()
+		if err != nil {
+			t.Fatalf("%v: %v", m, err)
+		}
+		if _, err := syscall.Write(s, wb); err != nil {
+			t.Fatalf("%v: %v", m, err)
+		}
+		rb := make([]byte, os.Getpagesize())
+		n, err := syscall.Read(s, rb)
+		if err != nil {
+			t.Fatalf("%v: %v", m, err)
+		}
+		rms, err := ParseRIB(0, rb[:n])
+		if err != nil {
+			t.Fatalf("%v: %v", m, err)
+		}
+		for _, rm := range rms {
+			err := rm.(*RouteMessage).Err
+			if err != nil {
+				t.Errorf("%v: %v", m, err)
+			}
+		}
+		ss, err := msgs(rms).validate()
+		if err != nil {
+			t.Fatalf("%v: %v", m, err)
+		}
+		for _, s := range ss {
+			t.Log(s)
+		}
+	}
+}
diff --git a/libgo/go/golang_org/x/net/route/route.go b/libgo/go/golang_org/x/net/route/route.go
index c986e29..081da0d 100644
--- a/libgo/go/golang_org/x/net/route/route.go
+++ b/libgo/go/golang_org/x/net/route/route.go
@@ -24,21 +24,70 @@
 	errMessageTooShort    = errors.New("message too short")
 	errInvalidMessage     = errors.New("invalid message")
 	errInvalidAddr        = errors.New("invalid address")
+	errShortBuffer        = errors.New("short buffer")
 )
 
 // A RouteMessage represents a message conveying an address prefix, a
 // nexthop address and an output interface.
+//
+// Unlike other messages, this message can be used to query adjacency
+// information for the given address prefix, to add a new route, and
+// to delete or modify the existing route from the routing information
+// base inside the kernel by writing and reading route messages on a
+// routing socket.
+//
+// For the manipulation of routing information, the route message must
+// contain appropriate fields that include:
+//
+//	Version       = <must be specified>
+//	Type          = <must be specified>
+//	Flags         = <must be specified>
+//	Index         = <must be specified if necessary>
+//	ID            = <must be specified>
+//	Seq           = <must be specified>
+//	Addrs         = <must be specified>
+//
+// The Type field specifies a type of manipulation, the Flags field
+// specifies a class of target information and the Addrs field
+// specifies target information like the following:
+//
+//	route.RouteMessage{
+//		Version: RTM_VERSION,
+//		Type: RTM_GET,
+//		Flags: RTF_UP | RTF_HOST,
+//		ID: uintptr(os.Getpid()),
+//		Seq: 1,
+//		Addrs: []route.Addrs{
+//			RTAX_DST: &route.Inet4Addr{ ... },
+//			RTAX_IFP: &route.LinkAddr{ ... },
+//			RTAX_BRD: &route.Inet4Addr{ ... },
+//		},
+//	}
+//
+// The values for the above fields depend on the implementation of
+// each operating system.
+//
+// The Err field on a response message contains an error value on the
+// requested operation. If non-nil, the requested operation is failed.
 type RouteMessage struct {
-	Version int    // message version
-	Type    int    // message type
-	Flags   int    // route flags
-	Index   int    // interface index when atatched
-	Addrs   []Addr // addresses
+	Version int     // message version
+	Type    int     // message type
+	Flags   int     // route flags
+	Index   int     // interface index when atatched
+	ID      uintptr // sender's identifier; usually process ID
+	Seq     int     // sequence number
+	Err     error   // error on requested operation
+	Addrs   []Addr  // addresses
 
 	extOff int    // offset of header extension
 	raw    []byte // raw message
 }
 
+// Marshal returns the binary encoding of m.
+func (m *RouteMessage) Marshal() ([]byte, error) {
+	return m.marshal()
+}
+
 // A RIBType reprensents a type of routing information base.
 type RIBType int
 
diff --git a/libgo/go/golang_org/x/net/route/route_classic.go b/libgo/go/golang_org/x/net/route/route_classic.go
index d333c6a..61b2bb4 100644
--- a/libgo/go/golang_org/x/net/route/route_classic.go
+++ b/libgo/go/golang_org/x/net/route/route_classic.go
@@ -6,6 +6,36 @@
 
 package route
 
+import "syscall"
+
+func (m *RouteMessage) marshal() ([]byte, error) {
+	w, ok := wireFormats[m.Type]
+	if !ok {
+		return nil, errUnsupportedMessage
+	}
+	l := w.bodyOff + addrsSpace(m.Addrs)
+	b := make([]byte, l)
+	nativeEndian.PutUint16(b[:2], uint16(l))
+	if m.Version == 0 {
+		b[2] = sysRTM_VERSION
+	} else {
+		b[2] = byte(m.Version)
+	}
+	b[3] = byte(m.Type)
+	nativeEndian.PutUint32(b[8:12], uint32(m.Flags))
+	nativeEndian.PutUint16(b[4:6], uint16(m.Index))
+	nativeEndian.PutUint32(b[16:20], uint32(m.ID))
+	nativeEndian.PutUint32(b[20:24], uint32(m.Seq))
+	attrs, err := marshalAddrs(b[w.bodyOff:], m.Addrs)
+	if err != nil {
+		return nil, err
+	}
+	if attrs > 0 {
+		nativeEndian.PutUint32(b[12:16], uint32(attrs))
+	}
+	return b, nil
+}
+
 func (w *wireFormat) parseRouteMessage(typ RIBType, b []byte) (Message, error) {
 	if len(b) < w.bodyOff {
 		return nil, errMessageTooShort
@@ -19,9 +49,15 @@
 		Type:    int(b[3]),
 		Flags:   int(nativeEndian.Uint32(b[8:12])),
 		Index:   int(nativeEndian.Uint16(b[4:6])),
+		ID:      uintptr(nativeEndian.Uint32(b[16:20])),
+		Seq:     int(nativeEndian.Uint32(b[20:24])),
 		extOff:  w.extOff,
 		raw:     b[:l],
 	}
+	errno := syscall.Errno(nativeEndian.Uint32(b[28:32]))
+	if errno != 0 {
+		m.Err = errno
+	}
 	var err error
 	m.Addrs, err = parseAddrs(uint(nativeEndian.Uint32(b[12:16])), parseKernelInetAddr, b[w.bodyOff:])
 	if err != nil {
diff --git a/libgo/go/golang_org/x/net/route/route_openbsd.go b/libgo/go/golang_org/x/net/route/route_openbsd.go
index 76eae40..daf2e90 100644
--- a/libgo/go/golang_org/x/net/route/route_openbsd.go
+++ b/libgo/go/golang_org/x/net/route/route_openbsd.go
@@ -4,8 +4,35 @@
 
 package route
 
+import "syscall"
+
+func (m *RouteMessage) marshal() ([]byte, error) {
+	l := sizeofRtMsghdr + addrsSpace(m.Addrs)
+	b := make([]byte, l)
+	nativeEndian.PutUint16(b[:2], uint16(l))
+	if m.Version == 0 {
+		b[2] = sysRTM_VERSION
+	} else {
+		b[2] = byte(m.Version)
+	}
+	b[3] = byte(m.Type)
+	nativeEndian.PutUint16(b[4:6], uint16(sizeofRtMsghdr))
+	nativeEndian.PutUint32(b[16:20], uint32(m.Flags))
+	nativeEndian.PutUint16(b[6:8], uint16(m.Index))
+	nativeEndian.PutUint32(b[24:28], uint32(m.ID))
+	nativeEndian.PutUint32(b[28:32], uint32(m.Seq))
+	attrs, err := marshalAddrs(b[sizeofRtMsghdr:], m.Addrs)
+	if err != nil {
+		return nil, err
+	}
+	if attrs > 0 {
+		nativeEndian.PutUint32(b[12:16], uint32(attrs))
+	}
+	return b, nil
+}
+
 func (*wireFormat) parseRouteMessage(_ RIBType, b []byte) (Message, error) {
-	if len(b) < 40 {
+	if len(b) < sizeofRtMsghdr {
 		return nil, errMessageTooShort
 	}
 	l := int(nativeEndian.Uint16(b[:2]))
@@ -17,12 +44,18 @@
 		Type:    int(b[3]),
 		Flags:   int(nativeEndian.Uint32(b[16:20])),
 		Index:   int(nativeEndian.Uint16(b[6:8])),
+		ID:      uintptr(nativeEndian.Uint32(b[24:28])),
+		Seq:     int(nativeEndian.Uint32(b[28:32])),
 		raw:     b[:l],
 	}
 	ll := int(nativeEndian.Uint16(b[4:6]))
 	if len(b) < ll {
 		return nil, errInvalidMessage
 	}
+	errno := syscall.Errno(nativeEndian.Uint32(b[32:36]))
+	if errno != 0 {
+		m.Err = errno
+	}
 	as, err := parseAddrs(uint(nativeEndian.Uint32(b[12:16])), parseKernelInetAddr, b[ll:])
 	if err != nil {
 		return nil, err
diff --git a/libgo/go/golang_org/x/net/route/sys.go b/libgo/go/golang_org/x/net/route/sys.go
index 80ca83a..3d0ee9b 100644
--- a/libgo/go/golang_org/x/net/route/sys.go
+++ b/libgo/go/golang_org/x/net/route/sys.go
@@ -11,7 +11,7 @@
 var (
 	nativeEndian binaryByteOrder
 	kernelAlign  int
-	parseFns     map[int]parseFn
+	wireFormats  map[int]*wireFormat
 )
 
 func init() {
@@ -22,7 +22,7 @@
 	} else {
 		nativeEndian = bigEndian
 	}
-	kernelAlign, parseFns = probeRoutingStack()
+	kernelAlign, wireFormats = probeRoutingStack()
 }
 
 func roundup(l int) int {
@@ -32,9 +32,8 @@
 	return (l + kernelAlign - 1) & ^(kernelAlign - 1)
 }
 
-type parseFn func(RIBType, []byte) (Message, error)
-
 type wireFormat struct {
 	extOff  int // offset of header extension
 	bodyOff int // offset of message body
+	parse   func(RIBType, []byte) (Message, error)
 }
diff --git a/libgo/go/golang_org/x/net/route/sys_darwin.go b/libgo/go/golang_org/x/net/route/sys_darwin.go
index fff3a0f..e742c91 100644
--- a/libgo/go/golang_org/x/net/route/sys_darwin.go
+++ b/libgo/go/golang_org/x/net/route/sys_darwin.go
@@ -49,32 +49,39 @@
 	}
 }
 
-func probeRoutingStack() (int, map[int]parseFn) {
+func probeRoutingStack() (int, map[int]*wireFormat) {
 	rtm := &wireFormat{extOff: 36, bodyOff: sizeofRtMsghdrDarwin15}
+	rtm.parse = rtm.parseRouteMessage
 	rtm2 := &wireFormat{extOff: 36, bodyOff: sizeofRtMsghdr2Darwin15}
+	rtm2.parse = rtm2.parseRouteMessage
 	ifm := &wireFormat{extOff: 16, bodyOff: sizeofIfMsghdrDarwin15}
+	ifm.parse = ifm.parseInterfaceMessage
 	ifm2 := &wireFormat{extOff: 32, bodyOff: sizeofIfMsghdr2Darwin15}
+	ifm2.parse = ifm2.parseInterfaceMessage
 	ifam := &wireFormat{extOff: sizeofIfaMsghdrDarwin15, bodyOff: sizeofIfaMsghdrDarwin15}
+	ifam.parse = ifam.parseInterfaceAddrMessage
 	ifmam := &wireFormat{extOff: sizeofIfmaMsghdrDarwin15, bodyOff: sizeofIfmaMsghdrDarwin15}
+	ifmam.parse = ifmam.parseInterfaceMulticastAddrMessage
 	ifmam2 := &wireFormat{extOff: sizeofIfmaMsghdr2Darwin15, bodyOff: sizeofIfmaMsghdr2Darwin15}
+	ifmam2.parse = ifmam2.parseInterfaceMulticastAddrMessage
 	// Darwin kernels require 32-bit aligned access to routing facilities.
-	return 4, map[int]parseFn{
-		sysRTM_ADD:       rtm.parseRouteMessage,
-		sysRTM_DELETE:    rtm.parseRouteMessage,
-		sysRTM_CHANGE:    rtm.parseRouteMessage,
-		sysRTM_GET:       rtm.parseRouteMessage,
-		sysRTM_LOSING:    rtm.parseRouteMessage,
-		sysRTM_REDIRECT:  rtm.parseRouteMessage,
-		sysRTM_MISS:      rtm.parseRouteMessage,
-		sysRTM_LOCK:      rtm.parseRouteMessage,
-		sysRTM_RESOLVE:   rtm.parseRouteMessage,
-		sysRTM_NEWADDR:   ifam.parseInterfaceAddrMessage,
-		sysRTM_DELADDR:   ifam.parseInterfaceAddrMessage,
-		sysRTM_IFINFO:    ifm.parseInterfaceMessage,
-		sysRTM_NEWMADDR:  ifmam.parseInterfaceMulticastAddrMessage,
-		sysRTM_DELMADDR:  ifmam.parseInterfaceMulticastAddrMessage,
-		sysRTM_IFINFO2:   ifm2.parseInterfaceMessage,
-		sysRTM_NEWMADDR2: ifmam2.parseInterfaceMulticastAddrMessage,
-		sysRTM_GET2:      rtm2.parseRouteMessage,
+	return 4, map[int]*wireFormat{
+		sysRTM_ADD:       rtm,
+		sysRTM_DELETE:    rtm,
+		sysRTM_CHANGE:    rtm,
+		sysRTM_GET:       rtm,
+		sysRTM_LOSING:    rtm,
+		sysRTM_REDIRECT:  rtm,
+		sysRTM_MISS:      rtm,
+		sysRTM_LOCK:      rtm,
+		sysRTM_RESOLVE:   rtm,
+		sysRTM_NEWADDR:   ifam,
+		sysRTM_DELADDR:   ifam,
+		sysRTM_IFINFO:    ifm,
+		sysRTM_NEWMADDR:  ifmam,
+		sysRTM_DELMADDR:  ifmam,
+		sysRTM_IFINFO2:   ifm2,
+		sysRTM_NEWMADDR2: ifmam2,
+		sysRTM_GET2:      rtm2,
 	}
 }
diff --git a/libgo/go/golang_org/x/net/route/sys_dragonfly.go b/libgo/go/golang_org/x/net/route/sys_dragonfly.go
index da848b3..b175cb1 100644
--- a/libgo/go/golang_org/x/net/route/sys_dragonfly.go
+++ b/libgo/go/golang_org/x/net/route/sys_dragonfly.go
@@ -44,28 +44,33 @@
 	}
 }
 
-func probeRoutingStack() (int, map[int]parseFn) {
+func probeRoutingStack() (int, map[int]*wireFormat) {
 	var p uintptr
 	rtm := &wireFormat{extOff: 40, bodyOff: sizeofRtMsghdrDragonFlyBSD4}
+	rtm.parse = rtm.parseRouteMessage
 	ifm := &wireFormat{extOff: 16, bodyOff: sizeofIfMsghdrDragonFlyBSD4}
+	ifm.parse = ifm.parseInterfaceMessage
 	ifam := &wireFormat{extOff: sizeofIfaMsghdrDragonFlyBSD4, bodyOff: sizeofIfaMsghdrDragonFlyBSD4}
+	ifam.parse = ifam.parseInterfaceAddrMessage
 	ifmam := &wireFormat{extOff: sizeofIfmaMsghdrDragonFlyBSD4, bodyOff: sizeofIfmaMsghdrDragonFlyBSD4}
+	ifmam.parse = ifmam.parseInterfaceMulticastAddrMessage
 	ifanm := &wireFormat{extOff: sizeofIfAnnouncemsghdrDragonFlyBSD4, bodyOff: sizeofIfAnnouncemsghdrDragonFlyBSD4}
-	return int(unsafe.Sizeof(p)), map[int]parseFn{
-		sysRTM_ADD:        rtm.parseRouteMessage,
-		sysRTM_DELETE:     rtm.parseRouteMessage,
-		sysRTM_CHANGE:     rtm.parseRouteMessage,
-		sysRTM_GET:        rtm.parseRouteMessage,
-		sysRTM_LOSING:     rtm.parseRouteMessage,
-		sysRTM_REDIRECT:   rtm.parseRouteMessage,
-		sysRTM_MISS:       rtm.parseRouteMessage,
-		sysRTM_LOCK:       rtm.parseRouteMessage,
-		sysRTM_RESOLVE:    rtm.parseRouteMessage,
-		sysRTM_NEWADDR:    ifam.parseInterfaceAddrMessage,
-		sysRTM_DELADDR:    ifam.parseInterfaceAddrMessage,
-		sysRTM_IFINFO:     ifm.parseInterfaceMessage,
-		sysRTM_NEWMADDR:   ifmam.parseInterfaceMulticastAddrMessage,
-		sysRTM_DELMADDR:   ifmam.parseInterfaceMulticastAddrMessage,
-		sysRTM_IFANNOUNCE: ifanm.parseInterfaceAnnounceMessage,
+	ifanm.parse = ifanm.parseInterfaceAnnounceMessage
+	return int(unsafe.Sizeof(p)), map[int]*wireFormat{
+		sysRTM_ADD:        rtm,
+		sysRTM_DELETE:     rtm,
+		sysRTM_CHANGE:     rtm,
+		sysRTM_GET:        rtm,
+		sysRTM_LOSING:     rtm,
+		sysRTM_REDIRECT:   rtm,
+		sysRTM_MISS:       rtm,
+		sysRTM_LOCK:       rtm,
+		sysRTM_RESOLVE:    rtm,
+		sysRTM_NEWADDR:    ifam,
+		sysRTM_DELADDR:    ifam,
+		sysRTM_IFINFO:     ifm,
+		sysRTM_NEWMADDR:   ifmam,
+		sysRTM_DELMADDR:   ifmam,
+		sysRTM_IFANNOUNCE: ifanm,
 	}
 }
diff --git a/libgo/go/golang_org/x/net/route/sys_freebsd.go b/libgo/go/golang_org/x/net/route/sys_freebsd.go
index 7b05c1a..010d4ae 100644
--- a/libgo/go/golang_org/x/net/route/sys_freebsd.go
+++ b/libgo/go/golang_org/x/net/route/sys_freebsd.go
@@ -54,7 +54,7 @@
 	}
 }
 
-func probeRoutingStack() (int, map[int]parseFn) {
+func probeRoutingStack() (int, map[int]*wireFormat) {
 	var p uintptr
 	wordSize := int(unsafe.Sizeof(p))
 	align := int(unsafe.Sizeof(p))
@@ -130,21 +130,26 @@
 			ifm.bodyOff = sizeofIfMsghdrFreeBSD11
 		}
 	}
-	return align, map[int]parseFn{
-		sysRTM_ADD:        rtm.parseRouteMessage,
-		sysRTM_DELETE:     rtm.parseRouteMessage,
-		sysRTM_CHANGE:     rtm.parseRouteMessage,
-		sysRTM_GET:        rtm.parseRouteMessage,
-		sysRTM_LOSING:     rtm.parseRouteMessage,
-		sysRTM_REDIRECT:   rtm.parseRouteMessage,
-		sysRTM_MISS:       rtm.parseRouteMessage,
-		sysRTM_LOCK:       rtm.parseRouteMessage,
-		sysRTM_RESOLVE:    rtm.parseRouteMessage,
-		sysRTM_NEWADDR:    ifam.parseInterfaceAddrMessage,
-		sysRTM_DELADDR:    ifam.parseInterfaceAddrMessage,
-		sysRTM_IFINFO:     ifm.parseInterfaceMessage,
-		sysRTM_NEWMADDR:   ifmam.parseInterfaceMulticastAddrMessage,
-		sysRTM_DELMADDR:   ifmam.parseInterfaceMulticastAddrMessage,
-		sysRTM_IFANNOUNCE: ifanm.parseInterfaceAnnounceMessage,
+	rtm.parse = rtm.parseRouteMessage
+	ifm.parse = ifm.parseInterfaceMessage
+	ifam.parse = ifam.parseInterfaceAddrMessage
+	ifmam.parse = ifmam.parseInterfaceMulticastAddrMessage
+	ifanm.parse = ifanm.parseInterfaceAnnounceMessage
+	return align, map[int]*wireFormat{
+		sysRTM_ADD:        rtm,
+		sysRTM_DELETE:     rtm,
+		sysRTM_CHANGE:     rtm,
+		sysRTM_GET:        rtm,
+		sysRTM_LOSING:     rtm,
+		sysRTM_REDIRECT:   rtm,
+		sysRTM_MISS:       rtm,
+		sysRTM_LOCK:       rtm,
+		sysRTM_RESOLVE:    rtm,
+		sysRTM_NEWADDR:    ifam,
+		sysRTM_DELADDR:    ifam,
+		sysRTM_IFINFO:     ifm,
+		sysRTM_NEWMADDR:   ifmam,
+		sysRTM_DELMADDR:   ifmam,
+		sysRTM_IFANNOUNCE: ifanm,
 	}
 }
diff --git a/libgo/go/golang_org/x/net/route/sys_netbsd.go b/libgo/go/golang_org/x/net/route/sys_netbsd.go
index 4d8076b..b4e3301 100644
--- a/libgo/go/golang_org/x/net/route/sys_netbsd.go
+++ b/libgo/go/golang_org/x/net/route/sys_netbsd.go
@@ -42,26 +42,30 @@
 	}
 }
 
-func probeRoutingStack() (int, map[int]parseFn) {
+func probeRoutingStack() (int, map[int]*wireFormat) {
 	rtm := &wireFormat{extOff: 40, bodyOff: sizeofRtMsghdrNetBSD7}
+	rtm.parse = rtm.parseRouteMessage
 	ifm := &wireFormat{extOff: 16, bodyOff: sizeofIfMsghdrNetBSD7}
+	ifm.parse = ifm.parseInterfaceMessage
 	ifam := &wireFormat{extOff: sizeofIfaMsghdrNetBSD7, bodyOff: sizeofIfaMsghdrNetBSD7}
+	ifam.parse = ifam.parseInterfaceAddrMessage
 	ifanm := &wireFormat{extOff: sizeofIfAnnouncemsghdrNetBSD7, bodyOff: sizeofIfAnnouncemsghdrNetBSD7}
+	ifanm.parse = ifanm.parseInterfaceAnnounceMessage
 	// NetBSD 6 and above kernels require 64-bit aligned access to
 	// routing facilities.
-	return 8, map[int]parseFn{
-		sysRTM_ADD:        rtm.parseRouteMessage,
-		sysRTM_DELETE:     rtm.parseRouteMessage,
-		sysRTM_CHANGE:     rtm.parseRouteMessage,
-		sysRTM_GET:        rtm.parseRouteMessage,
-		sysRTM_LOSING:     rtm.parseRouteMessage,
-		sysRTM_REDIRECT:   rtm.parseRouteMessage,
-		sysRTM_MISS:       rtm.parseRouteMessage,
-		sysRTM_LOCK:       rtm.parseRouteMessage,
-		sysRTM_RESOLVE:    rtm.parseRouteMessage,
-		sysRTM_NEWADDR:    ifam.parseInterfaceAddrMessage,
-		sysRTM_DELADDR:    ifam.parseInterfaceAddrMessage,
-		sysRTM_IFANNOUNCE: ifanm.parseInterfaceAnnounceMessage,
-		sysRTM_IFINFO:     ifm.parseInterfaceMessage,
+	return 8, map[int]*wireFormat{
+		sysRTM_ADD:        rtm,
+		sysRTM_DELETE:     rtm,
+		sysRTM_CHANGE:     rtm,
+		sysRTM_GET:        rtm,
+		sysRTM_LOSING:     rtm,
+		sysRTM_REDIRECT:   rtm,
+		sysRTM_MISS:       rtm,
+		sysRTM_LOCK:       rtm,
+		sysRTM_RESOLVE:    rtm,
+		sysRTM_NEWADDR:    ifam,
+		sysRTM_DELADDR:    ifam,
+		sysRTM_IFANNOUNCE: ifanm,
+		sysRTM_IFINFO:     ifm,
 	}
 }
diff --git a/libgo/go/golang_org/x/net/route/sys_openbsd.go b/libgo/go/golang_org/x/net/route/sys_openbsd.go
index 26d0438..8798dc4 100644
--- a/libgo/go/golang_org/x/net/route/sys_openbsd.go
+++ b/libgo/go/golang_org/x/net/route/sys_openbsd.go
@@ -51,22 +51,29 @@
 	}
 }
 
-func probeRoutingStack() (int, map[int]parseFn) {
+func probeRoutingStack() (int, map[int]*wireFormat) {
 	var p uintptr
-	nooff := &wireFormat{extOff: -1, bodyOff: -1}
-	return int(unsafe.Sizeof(p)), map[int]parseFn{
-		sysRTM_ADD:        nooff.parseRouteMessage,
-		sysRTM_DELETE:     nooff.parseRouteMessage,
-		sysRTM_CHANGE:     nooff.parseRouteMessage,
-		sysRTM_GET:        nooff.parseRouteMessage,
-		sysRTM_LOSING:     nooff.parseRouteMessage,
-		sysRTM_REDIRECT:   nooff.parseRouteMessage,
-		sysRTM_MISS:       nooff.parseRouteMessage,
-		sysRTM_LOCK:       nooff.parseRouteMessage,
-		sysRTM_RESOLVE:    nooff.parseRouteMessage,
-		sysRTM_NEWADDR:    nooff.parseInterfaceAddrMessage,
-		sysRTM_DELADDR:    nooff.parseInterfaceAddrMessage,
-		sysRTM_IFINFO:     nooff.parseInterfaceMessage,
-		sysRTM_IFANNOUNCE: nooff.parseInterfaceAnnounceMessage,
+	rtm := &wireFormat{extOff: -1, bodyOff: -1}
+	rtm.parse = rtm.parseRouteMessage
+	ifm := &wireFormat{extOff: -1, bodyOff: -1}
+	ifm.parse = ifm.parseInterfaceMessage
+	ifam := &wireFormat{extOff: -1, bodyOff: -1}
+	ifam.parse = ifam.parseInterfaceAddrMessage
+	ifanm := &wireFormat{extOff: -1, bodyOff: -1}
+	ifanm.parse = ifanm.parseInterfaceAnnounceMessage
+	return int(unsafe.Sizeof(p)), map[int]*wireFormat{
+		sysRTM_ADD:        rtm,
+		sysRTM_DELETE:     rtm,
+		sysRTM_CHANGE:     rtm,
+		sysRTM_GET:        rtm,
+		sysRTM_LOSING:     rtm,
+		sysRTM_REDIRECT:   rtm,
+		sysRTM_MISS:       rtm,
+		sysRTM_LOCK:       rtm,
+		sysRTM_RESOLVE:    rtm,
+		sysRTM_NEWADDR:    ifam,
+		sysRTM_DELADDR:    ifam,
+		sysRTM_IFINFO:     ifm,
+		sysRTM_IFANNOUNCE: ifanm,
 	}
 }
diff --git a/libgo/go/golang_org/x/net/route/syscall.go b/libgo/go/golang_org/x/net/route/syscall.go
index d136325..c211188 100644
--- a/libgo/go/golang_org/x/net/route/syscall.go
+++ b/libgo/go/golang_org/x/net/route/syscall.go
@@ -11,10 +11,6 @@
 	"unsafe"
 )
 
-// TODO: replace with runtime.KeepAlive when available
-//go:noescape
-func keepAlive(p unsafe.Pointer)
-
 var zero uintptr
 
 func sysctl(mib []int32, old *byte, oldlen *uintptr, new *byte, newlen uintptr) error {
@@ -25,7 +21,6 @@
 		p = unsafe.Pointer(&zero)
 	}
 	_, _, errno := syscall.Syscall6(syscall.SYS___SYSCTL, uintptr(p), uintptr(len(mib)), uintptr(unsafe.Pointer(old)), uintptr(unsafe.Pointer(oldlen)), uintptr(unsafe.Pointer(new)), uintptr(newlen))
-	keepAlive(p)
 	if errno != 0 {
 		return error(errno)
 	}
diff --git a/libgo/go/golang_org/x/net/route/zsys_darwin.go b/libgo/go/golang_org/x/net/route/zsys_darwin.go
index 265b81c..4e2e1ab 100644
--- a/libgo/go/golang_org/x/net/route/zsys_darwin.go
+++ b/libgo/go/golang_org/x/net/route/zsys_darwin.go
@@ -10,6 +10,8 @@
 	sysAF_LINK   = 0x12
 	sysAF_INET6  = 0x1e
 
+	sysSOCK_RAW = 0x3
+
 	sysNET_RT_DUMP    = 0x1
 	sysNET_RT_FLAGS   = 0x2
 	sysNET_RT_IFLIST  = 0x3
@@ -90,4 +92,8 @@
 	sizeofRtMsghdrDarwin15  = 0x5c
 	sizeofRtMsghdr2Darwin15 = 0x5c
 	sizeofRtMetricsDarwin15 = 0x38
+
+	sizeofSockaddrStorage = 0x80
+	sizeofSockaddrInet    = 0x10
+	sizeofSockaddrInet6   = 0x1c
 )
diff --git a/libgo/go/golang_org/x/net/route/zsys_dragonfly.go b/libgo/go/golang_org/x/net/route/zsys_dragonfly.go
index dd36dec..719c88d 100644
--- a/libgo/go/golang_org/x/net/route/zsys_dragonfly.go
+++ b/libgo/go/golang_org/x/net/route/zsys_dragonfly.go
@@ -10,6 +10,8 @@
 	sysAF_LINK   = 0x12
 	sysAF_INET6  = 0x1c
 
+	sysSOCK_RAW = 0x3
+
 	sysNET_RT_DUMP   = 0x1
 	sysNET_RT_FLAGS  = 0x2
 	sysNET_RT_IFLIST = 0x3
@@ -89,4 +91,8 @@
 
 	sizeofRtMsghdrDragonFlyBSD4  = 0x98
 	sizeofRtMetricsDragonFlyBSD4 = 0x70
+
+	sizeofSockaddrStorage = 0x80
+	sizeofSockaddrInet    = 0x10
+	sizeofSockaddrInet6   = 0x1c
 )
diff --git a/libgo/go/golang_org/x/net/route/zsys_freebsd_386.go b/libgo/go/golang_org/x/net/route/zsys_freebsd_386.go
index 9bac2e3..b03bc01 100644
--- a/libgo/go/golang_org/x/net/route/zsys_freebsd_386.go
+++ b/libgo/go/golang_org/x/net/route/zsys_freebsd_386.go
@@ -10,6 +10,8 @@
 	sysAF_LINK   = 0x12
 	sysAF_INET6  = 0x1c
 
+	sysSOCK_RAW = 0x3
+
 	sysNET_RT_DUMP     = 0x1
 	sysNET_RT_FLAGS    = 0x2
 	sysNET_RT_IFLIST   = 0x3
@@ -117,4 +119,8 @@
 	sizeofIfDataFreeBSD9Emu  = 0x98
 	sizeofIfDataFreeBSD10Emu = 0x98
 	sizeofIfDataFreeBSD11Emu = 0x98
+
+	sizeofSockaddrStorage = 0x80
+	sizeofSockaddrInet    = 0x10
+	sizeofSockaddrInet6   = 0x1c
 )
diff --git a/libgo/go/golang_org/x/net/route/zsys_freebsd_amd64.go b/libgo/go/golang_org/x/net/route/zsys_freebsd_amd64.go
index b1920d7..0b675b3 100644
--- a/libgo/go/golang_org/x/net/route/zsys_freebsd_amd64.go
+++ b/libgo/go/golang_org/x/net/route/zsys_freebsd_amd64.go
@@ -10,6 +10,8 @@
 	sysAF_LINK   = 0x12
 	sysAF_INET6  = 0x1c
 
+	sysSOCK_RAW = 0x3
+
 	sysNET_RT_DUMP     = 0x1
 	sysNET_RT_FLAGS    = 0x2
 	sysNET_RT_IFLIST   = 0x3
@@ -114,4 +116,8 @@
 	sizeofIfDataFreeBSD9Emu  = 0x98
 	sizeofIfDataFreeBSD10Emu = 0x98
 	sizeofIfDataFreeBSD11Emu = 0x98
+
+	sizeofSockaddrStorage = 0x80
+	sizeofSockaddrInet    = 0x10
+	sizeofSockaddrInet6   = 0x1c
 )
diff --git a/libgo/go/golang_org/x/net/route/zsys_freebsd_arm.go b/libgo/go/golang_org/x/net/route/zsys_freebsd_arm.go
index a034d6f..58f8ea1 100644
--- a/libgo/go/golang_org/x/net/route/zsys_freebsd_arm.go
+++ b/libgo/go/golang_org/x/net/route/zsys_freebsd_arm.go
@@ -10,6 +10,8 @@
 	sysAF_LINK   = 0x12
 	sysAF_INET6  = 0x1c
 
+	sysSOCK_RAW = 0x3
+
 	sysNET_RT_DUMP     = 0x1
 	sysNET_RT_FLAGS    = 0x2
 	sysNET_RT_IFLIST   = 0x3
@@ -114,4 +116,8 @@
 	sizeofIfDataFreeBSD9Emu  = 0x60
 	sizeofIfDataFreeBSD10Emu = 0x60
 	sizeofIfDataFreeBSD11Emu = 0x98
+
+	sizeofSockaddrStorage = 0x80
+	sizeofSockaddrInet    = 0x10
+	sizeofSockaddrInet6   = 0x1c
 )
diff --git a/libgo/go/golang_org/x/net/route/zsys_netbsd.go b/libgo/go/golang_org/x/net/route/zsys_netbsd.go
index aa4aad1..e0df45e 100644
--- a/libgo/go/golang_org/x/net/route/zsys_netbsd.go
+++ b/libgo/go/golang_org/x/net/route/zsys_netbsd.go
@@ -10,6 +10,8 @@
 	sysAF_LINK   = 0x12
 	sysAF_INET6  = 0x18
 
+	sysSOCK_RAW = 0x3
+
 	sysNET_RT_DUMP   = 0x1
 	sysNET_RT_FLAGS  = 0x2
 	sysNET_RT_IFLIST = 0x5
@@ -88,4 +90,8 @@
 
 	sizeofRtMsghdrNetBSD7  = 0x78
 	sizeofRtMetricsNetBSD7 = 0x50
+
+	sizeofSockaddrStorage = 0x80
+	sizeofSockaddrInet    = 0x10
+	sizeofSockaddrInet6   = 0x1c
 )
diff --git a/libgo/go/golang_org/x/net/route/zsys_openbsd.go b/libgo/go/golang_org/x/net/route/zsys_openbsd.go
index 4fadc4e..f5a1ff9 100644
--- a/libgo/go/golang_org/x/net/route/zsys_openbsd.go
+++ b/libgo/go/golang_org/x/net/route/zsys_openbsd.go
@@ -10,6 +10,8 @@
 	sysAF_LINK   = 0x12
 	sysAF_INET6  = 0x18
 
+	sysSOCK_RAW = 0x3
+
 	sysNET_RT_DUMP    = 0x1
 	sysNET_RT_FLAGS   = 0x2
 	sysNET_RT_IFLIST  = 0x3
@@ -78,3 +80,11 @@
 	sysRTAX_LABEL   = 0xa
 	sysRTAX_MAX     = 0xb
 )
+
+const (
+	sizeofRtMsghdr = 0x60
+
+	sizeofSockaddrStorage = 0x100
+	sizeofSockaddrInet    = 0x10
+	sizeofSockaddrInet6   = 0x1c
+)
diff --git a/libgo/go/golang_org/x/text/secure/bidirule/bidirule.go b/libgo/go/golang_org/x/text/secure/bidirule/bidirule.go
new file mode 100644
index 0000000..9f9594e
--- /dev/null
+++ b/libgo/go/golang_org/x/text/secure/bidirule/bidirule.go
@@ -0,0 +1,344 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bidirule implements the Bidi Rule defined by RFC 5893.
+//
+// This package is under development. The API may change without notice and
+// without preserving backward compatibility.
+package bidirule
+
+import (
+	"errors"
+	"unicode/utf8"
+
+	"golang_org/x/text/transform"
+	"golang_org/x/text/unicode/bidi"
+)
+
+// This file contains an implementation of RFC 5893: Right-to-Left Scripts for
+// Internationalized Domain Names for Applications (IDNA)
+//
+// A label is an individual component of a domain name.  Labels are usually
+// shown separated by dots; for example, the domain name "www.example.com" is
+// composed of three labels: "www", "example", and "com".
+//
+// An RTL label is a label that contains at least one character of class R, AL,
+// or AN. An LTR label is any label that is not an RTL label.
+//
+// A "Bidi domain name" is a domain name that contains at least one RTL label.
+//
+//  The following guarantees can be made based on the above:
+//
+//  o  In a domain name consisting of only labels that satisfy the rule,
+//     the requirements of Section 3 are satisfied.  Note that even LTR
+//     labels and pure ASCII labels have to be tested.
+//
+//  o  In a domain name consisting of only LDH labels (as defined in the
+//     Definitions document [RFC5890]) and labels that satisfy the rule,
+//     the requirements of Section 3 are satisfied as long as a label
+//     that starts with an ASCII digit does not come after a
+//     right-to-left label.
+//
+//  No guarantee is given for other combinations.
+
+// ErrInvalid indicates a label is invalid according to the Bidi Rule.
+var ErrInvalid = errors.New("bidirule: failed Bidi Rule")
+
+type ruleState uint8
+
+const (
+	ruleInitial ruleState = iota
+	ruleLTR
+	ruleLTRFinal
+	ruleRTL
+	ruleRTLFinal
+	ruleInvalid
+)
+
+type ruleTransition struct {
+	next ruleState
+	mask uint16
+}
+
+var transitions = [...][2]ruleTransition{
+	// [2.1] The first character must be a character with Bidi property L, R, or
+	// AL. If it has the R or AL property, it is an RTL label; if it has the L
+	// property, it is an LTR label.
+	ruleInitial: {
+		{ruleLTRFinal, 1 << bidi.L},
+		{ruleRTLFinal, 1<<bidi.R | 1<<bidi.AL},
+	},
+	ruleRTL: {
+		// [2.3] In an RTL label, the end of the label must be a character with
+		// Bidi property R, AL, EN, or AN, followed by zero or more characters
+		// with Bidi property NSM.
+		{ruleRTLFinal, 1<<bidi.R | 1<<bidi.AL | 1<<bidi.EN | 1<<bidi.AN},
+
+		// [2.2] In an RTL label, only characters with the Bidi properties R,
+		// AL, AN, EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.3]
+		{ruleRTL, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN | 1<<bidi.NSM},
+	},
+	ruleRTLFinal: {
+		// [2.3] In an RTL label, the end of the label must be a character with
+		// Bidi property R, AL, EN, or AN, followed by zero or more characters
+		// with Bidi property NSM.
+		{ruleRTLFinal, 1<<bidi.R | 1<<bidi.AL | 1<<bidi.EN | 1<<bidi.AN | 1<<bidi.NSM},
+
+		// [2.2] In an RTL label, only characters with the Bidi properties R,
+		// AL, AN, EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.3] and NSM.
+		{ruleRTL, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN},
+	},
+	ruleLTR: {
+		// [2.6] In an LTR label, the end of the label must be a character with
+		// Bidi property L or EN, followed by zero or more characters with Bidi
+		// property NSM.
+		{ruleLTRFinal, 1<<bidi.L | 1<<bidi.EN},
+
+		// [2.5] In an LTR label, only characters with the Bidi properties L,
+		// EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.6].
+		{ruleLTR, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN | 1<<bidi.NSM},
+	},
+	ruleLTRFinal: {
+		// [2.6] In an LTR label, the end of the label must be a character with
+		// Bidi property L or EN, followed by zero or more characters with Bidi
+		// property NSM.
+		{ruleLTRFinal, 1<<bidi.L | 1<<bidi.EN | 1<<bidi.NSM},
+
+		// [2.5] In an LTR label, only characters with the Bidi properties L,
+		// EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.6].
+		{ruleLTR, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN},
+	},
+	ruleInvalid: {
+		{ruleInvalid, 0},
+		{ruleInvalid, 0},
+	},
+}
+
+// [2.4] In an RTL label, if an EN is present, no AN may be present, and
+// vice versa.
+const exclusiveRTL = uint16(1<<bidi.EN | 1<<bidi.AN)
+
+// From RFC 5893
+// An RTL label is a label that contains at least one character of type
+// R, AL, or AN.
+//
+// An LTR label is any label that is not an RTL label.
+
+// Direction reports the direction of the given label as defined by RFC 5893.
+// The Bidi Rule does not have to be applied to labels of the category
+// LeftToRight.
+func Direction(b []byte) bidi.Direction {
+	for i := 0; i < len(b); {
+		e, sz := bidi.Lookup(b[i:])
+		if sz == 0 {
+			i++
+		}
+		c := e.Class()
+		if c == bidi.R || c == bidi.AL || c == bidi.AN {
+			return bidi.RightToLeft
+		}
+		i += sz
+	}
+	return bidi.LeftToRight
+}
+
+// DirectionString reports the direction of the given label as defined by RFC
+// 5893. The Bidi Rule does not have to be applied to labels of the category
+// LeftToRight.
+func DirectionString(s string) bidi.Direction {
+	for i := 0; i < len(s); {
+		e, sz := bidi.LookupString(s[i:])
+		if sz == 0 {
+			i++
+		}
+		c := e.Class()
+		if c == bidi.R || c == bidi.AL || c == bidi.AN {
+			return bidi.RightToLeft
+		}
+		i += sz
+	}
+	return bidi.LeftToRight
+}
+
+// Valid reports whether b conforms to the BiDi rule.
+func Valid(b []byte) bool {
+	var t Transformer
+	if n, ok := t.advance(b); !ok || n < len(b) {
+		return false
+	}
+	return t.isFinal()
+}
+
+// ValidString reports whether s conforms to the BiDi rule.
+func ValidString(s string) bool {
+	var t Transformer
+	if n, ok := t.advanceString(s); !ok || n < len(s) {
+		return false
+	}
+	return t.isFinal()
+}
+
+// New returns a Transformer that verifies that input adheres to the Bidi Rule.
+func New() *Transformer {
+	return &Transformer{}
+}
+
+// Transformer implements transform.Transform.
+type Transformer struct {
+	state  ruleState
+	hasRTL bool
+	seen   uint16
+}
+
+// A rule can only be violated for "Bidi Domain names", meaning if one of the
+// following categories has been observed.
+func (t *Transformer) isRTL() bool {
+	const isRTL = 1<<bidi.R | 1<<bidi.AL | 1<<bidi.AN
+	return t.seen&isRTL != 0
+}
+
+func (t *Transformer) isFinal() bool {
+	if !t.isRTL() {
+		return true
+	}
+	return t.state == ruleLTRFinal || t.state == ruleRTLFinal || t.state == ruleInitial
+}
+
+// Reset implements transform.Transformer.
+func (t *Transformer) Reset() { *t = Transformer{} }
+
+// Transform implements transform.Transformer. This Transformer has state and
+// needs to be reset between uses.
+func (t *Transformer) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	if len(dst) < len(src) {
+		src = src[:len(dst)]
+		atEOF = false
+		err = transform.ErrShortDst
+	}
+	n, err1 := t.Span(src, atEOF)
+	copy(dst, src[:n])
+	if err == nil || err1 != nil && err1 != transform.ErrShortSrc {
+		err = err1
+	}
+	return n, n, err
+}
+
+// Span returns the first n bytes of src that conform to the Bidi rule.
+func (t *Transformer) Span(src []byte, atEOF bool) (n int, err error) {
+	if t.state == ruleInvalid && t.isRTL() {
+		return 0, ErrInvalid
+	}
+	n, ok := t.advance(src)
+	switch {
+	case !ok:
+		err = ErrInvalid
+	case n < len(src):
+		if !atEOF {
+			err = transform.ErrShortSrc
+			break
+		}
+		err = ErrInvalid
+	case !t.isFinal():
+		err = ErrInvalid
+	}
+	return n, err
+}
+
+// Precomputing the ASCII values decreases running time for the ASCII fast path
+// by about 30%.
+var asciiTable [128]bidi.Properties
+
+func init() {
+	for i := range asciiTable {
+		p, _ := bidi.LookupRune(rune(i))
+		asciiTable[i] = p
+	}
+}
+
+func (t *Transformer) advance(s []byte) (n int, ok bool) {
+	var e bidi.Properties
+	var sz int
+	for n < len(s) {
+		if s[n] < utf8.RuneSelf {
+			e, sz = asciiTable[s[n]], 1
+		} else {
+			e, sz = bidi.Lookup(s[n:])
+			if sz <= 1 {
+				if sz == 1 {
+					// We always consider invalid UTF-8 to be invalid, even if
+					// the string has not yet been determined to be RTL.
+					// TODO: is this correct?
+					return n, false
+				}
+				return n, true // incomplete UTF-8 encoding
+			}
+		}
+		// TODO: using CompactClass would result in noticeable speedup.
+		// See unicode/bidi/prop.go:Properties.CompactClass.
+		c := uint16(1 << e.Class())
+		t.seen |= c
+		if t.seen&exclusiveRTL == exclusiveRTL {
+			t.state = ruleInvalid
+			return n, false
+		}
+		switch tr := transitions[t.state]; {
+		case tr[0].mask&c != 0:
+			t.state = tr[0].next
+		case tr[1].mask&c != 0:
+			t.state = tr[1].next
+		default:
+			t.state = ruleInvalid
+			if t.isRTL() {
+				return n, false
+			}
+		}
+		n += sz
+	}
+	return n, true
+}
+
+func (t *Transformer) advanceString(s string) (n int, ok bool) {
+	var e bidi.Properties
+	var sz int
+	for n < len(s) {
+		if s[n] < utf8.RuneSelf {
+			e, sz = asciiTable[s[n]], 1
+		} else {
+			e, sz = bidi.LookupString(s[n:])
+			if sz <= 1 {
+				if sz == 1 {
+					return n, false // invalid UTF-8
+				}
+				return n, true // incomplete UTF-8 encoding
+			}
+		}
+		// TODO: using CompactClass results in noticeable speedup.
+		// See unicode/bidi/prop.go:Properties.CompactClass.
+		c := uint16(1 << e.Class())
+		t.seen |= c
+		if t.seen&exclusiveRTL == exclusiveRTL {
+			t.state = ruleInvalid
+			return n, false
+		}
+		switch tr := transitions[t.state]; {
+		case tr[0].mask&c != 0:
+			t.state = tr[0].next
+		case tr[1].mask&c != 0:
+			t.state = tr[1].next
+		default:
+			t.state = ruleInvalid
+			if t.isRTL() {
+				return n, false
+			}
+		}
+		n += sz
+	}
+	return n, true
+}
diff --git a/libgo/go/golang_org/x/text/secure/doc.go b/libgo/go/golang_org/x/text/secure/doc.go
new file mode 100644
index 0000000..4912b9b
--- /dev/null
+++ b/libgo/go/golang_org/x/text/secure/doc.go
@@ -0,0 +1,8 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// secure is a repository of text security related packages.
+package secure // import "golang_org/x/text/secure"
diff --git a/libgo/go/golang_org/x/text/transform/examples_test.go b/libgo/go/golang_org/x/text/transform/examples_test.go
new file mode 100644
index 0000000..1323d9b
--- /dev/null
+++ b/libgo/go/golang_org/x/text/transform/examples_test.go
@@ -0,0 +1,39 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package transform_test
+
+import (
+	"fmt"
+	"unicode"
+
+	"golang_org/x/text/transform"
+	"golang_org/x/text/unicode/norm"
+)
+
+func ExampleRemoveFunc() {
+	input := []byte(`tschüß; до свидания`)
+
+	b := make([]byte, len(input))
+
+	t := transform.RemoveFunc(unicode.IsSpace)
+	n, _, _ := t.Transform(b, input, true)
+	fmt.Println(string(b[:n]))
+
+	t = transform.RemoveFunc(func(r rune) bool {
+		return !unicode.Is(unicode.Latin, r)
+	})
+	n, _, _ = t.Transform(b, input, true)
+	fmt.Println(string(b[:n]))
+
+	n, _, _ = t.Transform(b, norm.NFD.Bytes(input), true)
+	fmt.Println(string(b[:n]))
+
+	// Output:
+	// tschüß;досвидания
+	// tschüß
+	// tschuß
+}
diff --git a/libgo/go/golang_org/x/text/transform/transform.go b/libgo/go/golang_org/x/text/transform/transform.go
index fe47b9b..2a1b190 100644
--- a/libgo/go/golang_org/x/text/transform/transform.go
+++ b/libgo/go/golang_org/x/text/transform/transform.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2013 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
@@ -6,7 +8,7 @@
 // bytes passing through as well as various transformations. Example
 // transformations provided by other packages include normalization and
 // conversion between character sets.
-package transform // import "golang.org/x/text/transform"
+package transform // import "golang_org/x/text/transform"
 
 import (
 	"bytes"
diff --git a/libgo/go/golang_org/x/text/unicode/bidi/bidi.go b/libgo/go/golang_org/x/text/unicode/bidi/bidi.go
new file mode 100644
index 0000000..4c9735e
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/bidi/bidi.go
@@ -0,0 +1,198 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bidi contains functionality for bidirectional text support.
+//
+// See http://www.unicode.org/reports/tr9.
+//
+// NOTE: UNDER CONSTRUCTION. This API may change in backwards incompatible ways
+// and without notice.
+package bidi // import "golang_org/x/text/unicode/bidi"
+
+// TODO:
+// The following functionality would not be hard to implement, but hinges on
+// the definition of a Segmenter interface. For now this is up to the user.
+// - Iterate over paragraphs
+// - Segmenter to iterate over runs directly from a given text.
+// Also:
+// - Transformer for reordering?
+// - Transformer (validator, really) for Bidi Rule.
+
+// This API tries to avoid dealing with embedding levels for now. Under the hood
+// these will be computed, but the question is to which extent the user should
+// know they exist. We should at some point allow the user to specify an
+// embedding hierarchy, though.
+
+// A Direction indicates the overall flow of text.
+type Direction int
+
+const (
+	// LeftToRight indicates the text contains no right-to-left characters and
+	// that either there are some left-to-right characters or the option
+	// DefaultDirection(LeftToRight) was passed.
+	LeftToRight Direction = iota
+
+	// RightToLeft indicates the text contains no left-to-right characters and
+	// that either there are some right-to-left characters or the option
+	// DefaultDirection(RightToLeft) was passed.
+	RightToLeft
+
+	// Mixed indicates text contains both left-to-right and right-to-left
+	// characters.
+	Mixed
+
+	// Neutral means that text contains no left-to-right and right-to-left
+	// characters and that no default direction has been set.
+	Neutral
+)
+
+type options struct{}
+
+// An Option is an option for Bidi processing.
+type Option func(*options)
+
+// ICU allows the user to define embedding levels. This may be used, for example,
+// to use hierarchical structure of markup languages to define embeddings.
+// The following option may be a way to expose this functionality in this API.
+// // LevelFunc sets a function that associates nesting levels with the given text.
+// // The levels function will be called with monotonically increasing values for p.
+// func LevelFunc(levels func(p int) int) Option {
+// 	panic("unimplemented")
+// }
+
+// DefaultDirection sets the default direction for a Paragraph. The direction is
+// overridden if the text contains directional characters.
+func DefaultDirection(d Direction) Option {
+	panic("unimplemented")
+}
+
+// A Paragraph holds a single Paragraph for Bidi processing.
+type Paragraph struct {
+	// buffers
+}
+
+// SetBytes configures p for the given paragraph text. It replaces text
+// previously set by SetBytes or SetString. If b contains a paragraph separator
+// it will only process the first paragraph and report the number of bytes
+// consumed from b including this separator. Error may be non-nil if options are
+// given.
+func (p *Paragraph) SetBytes(b []byte, opts ...Option) (n int, err error) {
+	panic("unimplemented")
+}
+
+// SetString configures p for the given paragraph text. It replaces text
+// previously set by SetBytes or SetString. If b contains a paragraph separator
+// it will only process the first paragraph and report the number of bytes
+// consumed from b including this separator. Error may be non-nil if options are
+// given.
+func (p *Paragraph) SetString(s string, opts ...Option) (n int, err error) {
+	panic("unimplemented")
+}
+
+// IsLeftToRight reports whether the principle direction of rendering for this
+// paragraphs is left-to-right. If this returns false, the principle direction
+// of rendering is right-to-left.
+func (p *Paragraph) IsLeftToRight() bool {
+	panic("unimplemented")
+}
+
+// Direction returns the direction of the text of this paragraph.
+//
+// The direction may be LeftToRight, RightToLeft, Mixed, or Neutral.
+func (p *Paragraph) Direction() Direction {
+	panic("unimplemented")
+}
+
+// RunAt reports the Run at the given position of the input text.
+//
+// This method can be used for computing line breaks on paragraphs.
+func (p *Paragraph) RunAt(pos int) Run {
+	panic("unimplemented")
+}
+
+// Order computes the visual ordering of all the runs in a Paragraph.
+func (p *Paragraph) Order() (Ordering, error) {
+	panic("unimplemented")
+}
+
+// Line computes the visual ordering of runs for a single line starting and
+// ending at the given positions in the original text.
+func (p *Paragraph) Line(start, end int) (Ordering, error) {
+	panic("unimplemented")
+}
+
+// An Ordering holds the computed visual order of runs of a Paragraph. Calling
+// SetBytes or SetString on the originating Paragraph invalidates an Ordering.
+// The methods of an Ordering should only be called by one goroutine at a time.
+type Ordering struct{}
+
+// Direction reports the directionality of the runs.
+//
+// The direction may be LeftToRight, RightToLeft, Mixed, or Neutral.
+func (o *Ordering) Direction() Direction {
+	panic("unimplemented")
+}
+
+// NumRuns returns the number of runs.
+func (o *Ordering) NumRuns() int {
+	panic("unimplemented")
+}
+
+// Run returns the ith run within the ordering.
+func (o *Ordering) Run(i int) Run {
+	panic("unimplemented")
+}
+
+// TODO: perhaps with options.
+// // Reorder creates a reader that reads the runes in visual order per character.
+// // Modifiers remain after the runes they modify.
+// func (l *Runs) Reorder() io.Reader {
+// 	panic("unimplemented")
+// }
+
+// A Run is a continuous sequence of characters of a single direction.
+type Run struct {
+}
+
+// String returns the text of the run in its original order.
+func (r *Run) String() string {
+	panic("unimplemented")
+}
+
+// Bytes returns the text of the run in its original order.
+func (r *Run) Bytes() []byte {
+	panic("unimplemented")
+}
+
+// TODO: methods for
+// - Display order
+// - headers and footers
+// - bracket replacement.
+
+// Direction reports the direction of the run.
+func (r *Run) Direction() Direction {
+	panic("unimplemented")
+}
+
+// Position of the Run within the text passed to SetBytes or SetString of the
+// originating Paragraph value.
+func (r *Run) Pos() (start, end int) {
+	panic("unimplemented")
+}
+
+// AppendReverse reverses the order of characters of in, appends them to out,
+// and returns the result. Modifiers will still follow the runes they modify.
+// Brackets are replaced with their counterparts.
+func AppendReverse(out, in []byte) []byte {
+	panic("unimplemented")
+}
+
+// ReverseString reverses the order of characters in s and returns a new string.
+// Modifiers will still follow the runes they modify. Brackets are replaced with
+// their counterparts.
+func ReverseString(s string) string {
+	panic("unimplemented")
+}
diff --git a/libgo/go/golang_org/x/text/unicode/bidi/bracket.go b/libgo/go/golang_org/x/text/unicode/bidi/bracket.go
new file mode 100644
index 0000000..f08a93d
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/bidi/bracket.go
@@ -0,0 +1,337 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bidi
+
+import (
+	"container/list"
+	"fmt"
+	"sort"
+)
+
+// This file contains a port of the reference implementation of the
+// Bidi Parentheses Algorithm:
+// http://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/BidiPBAReference.java
+//
+// The implementation in this file covers definitions BD14-BD16 and rule N0
+// of UAX#9.
+//
+// Some preprocessing is done for each rune before data is passed to this
+// algorithm:
+//  - opening and closing brackets are identified
+//  - a bracket pair type, like '(' and ')' is assigned a unique identifier that
+//    is identical for the opening and closing bracket. It is left to do these
+//    mappings.
+//  - The BPA algorithm requires that bracket characters that are canonical
+//    equivalents of each other be able to be substituted for each other.
+//    It is the responsibility of the caller to do this canonicalization.
+//
+// In implementing BD16, this implementation departs slightly from the "logical"
+// algorithm defined in UAX#9. In particular, the stack referenced there
+// supports operations that go beyond a "basic" stack. An equivalent
+// implementation based on a linked list is used here.
+
+// Bidi_Paired_Bracket_Type
+// BD14. An opening paired bracket is a character whose
+// Bidi_Paired_Bracket_Type property value is Open.
+//
+// BD15. A closing paired bracket is a character whose
+// Bidi_Paired_Bracket_Type property value is Close.
+type bracketType byte
+
+const (
+	bpNone bracketType = iota
+	bpOpen
+	bpClose
+)
+
+// bracketPair holds a pair of index values for opening and closing bracket
+// location of a bracket pair.
+type bracketPair struct {
+	opener int
+	closer int
+}
+
+func (b *bracketPair) String() string {
+	return fmt.Sprintf("(%v, %v)", b.opener, b.closer)
+}
+
+// bracketPairs is a slice of bracketPairs with a sort.Interface implementation.
+type bracketPairs []bracketPair
+
+func (b bracketPairs) Len() int           { return len(b) }
+func (b bracketPairs) Swap(i, j int)      { b[i], b[j] = b[j], b[i] }
+func (b bracketPairs) Less(i, j int) bool { return b[i].opener < b[j].opener }
+
+// resolvePairedBrackets runs the paired bracket part of the UBA algorithm.
+//
+// For each rune, it takes the indexes into the original string, the class the
+// bracket type (in pairTypes) and the bracket identifier (pairValues). It also
+// takes the direction type for the start-of-sentence and the embedding level.
+//
+// The identifiers for bracket types are the rune of the canonicalized opening
+// bracket for brackets (open or close) or 0 for runes that are not brackets.
+func resolvePairedBrackets(s *isolatingRunSequence) {
+	p := bracketPairer{
+		sos:              s.sos,
+		openers:          list.New(),
+		codesIsolatedRun: s.types,
+		indexes:          s.indexes,
+	}
+	dirEmbed := L
+	if s.level&1 != 0 {
+		dirEmbed = R
+	}
+	p.locateBrackets(s.p.pairTypes, s.p.pairValues)
+	p.resolveBrackets(dirEmbed, s.p.initialTypes)
+}
+
+type bracketPairer struct {
+	sos Class // direction corresponding to start of sequence
+
+	// The following is a restatement of BD 16 using non-algorithmic language.
+	//
+	// A bracket pair is a pair of characters consisting of an opening
+	// paired bracket and a closing paired bracket such that the
+	// Bidi_Paired_Bracket property value of the former equals the latter,
+	// subject to the following constraints.
+	// - both characters of a pair occur in the same isolating run sequence
+	// - the closing character of a pair follows the opening character
+	// - any bracket character can belong at most to one pair, the earliest possible one
+	// - any bracket character not part of a pair is treated like an ordinary character
+	// - pairs may nest properly, but their spans may not overlap otherwise
+
+	// Bracket characters with canonical decompositions are supposed to be
+	// treated as if they had been normalized, to allow normalized and non-
+	// normalized text to give the same result. In this implementation that step
+	// is pushed out to the caller. The caller has to ensure that the pairValue
+	// slices contain the rune of the opening bracket after normalization for
+	// any opening or closing bracket.
+
+	openers *list.List // list of positions for opening brackets
+
+	// bracket pair positions sorted by location of opening bracket
+	pairPositions bracketPairs
+
+	codesIsolatedRun []Class // directional bidi codes for an isolated run
+	indexes          []int   // array of index values into the original string
+
+}
+
+// matchOpener reports whether characters at given positions form a matching
+// bracket pair.
+func (p *bracketPairer) matchOpener(pairValues []rune, opener, closer int) bool {
+	return pairValues[p.indexes[opener]] == pairValues[p.indexes[closer]]
+}
+
+const maxPairingDepth = 63
+
+// locateBrackets locates matching bracket pairs according to BD16.
+//
+// This implementation uses a linked list instead of a stack, because, while
+// elements are added at the front (like a push) they are not generally removed
+// in atomic 'pop' operations, reducing the benefit of the stack archetype.
+func (p *bracketPairer) locateBrackets(pairTypes []bracketType, pairValues []rune) {
+	// traverse the run
+	// do that explicitly (not in a for-each) so we can record position
+	for i, index := range p.indexes {
+
+		// look at the bracket type for each character
+		if pairTypes[index] == bpNone || p.codesIsolatedRun[i] != ON {
+			// continue scanning
+			continue
+		}
+		switch pairTypes[index] {
+		case bpOpen:
+			// check if maximum pairing depth reached
+			if p.openers.Len() == maxPairingDepth {
+				p.openers.Init()
+				return
+			}
+			// remember opener location, most recent first
+			p.openers.PushFront(i)
+
+		case bpClose:
+			// see if there is a match
+			count := 0
+			for elem := p.openers.Front(); elem != nil; elem = elem.Next() {
+				count++
+				opener := elem.Value.(int)
+				if p.matchOpener(pairValues, opener, i) {
+					// if the opener matches, add nested pair to the ordered list
+					p.pairPositions = append(p.pairPositions, bracketPair{opener, i})
+					// remove up to and including matched opener
+					for ; count > 0; count-- {
+						p.openers.Remove(p.openers.Front())
+					}
+					break
+				}
+			}
+			sort.Sort(p.pairPositions)
+			// if we get here, the closing bracket matched no openers
+			// and gets ignored
+		}
+	}
+}
+
+// Bracket pairs within an isolating run sequence are processed as units so
+// that both the opening and the closing paired bracket in a pair resolve to
+// the same direction.
+//
+// N0. Process bracket pairs in an isolating run sequence sequentially in
+// the logical order of the text positions of the opening paired brackets
+// using the logic given below. Within this scope, bidirectional types EN
+// and AN are treated as R.
+//
+// Identify the bracket pairs in the current isolating run sequence
+// according to BD16. For each bracket-pair element in the list of pairs of
+// text positions:
+//
+// a Inspect the bidirectional types of the characters enclosed within the
+// bracket pair.
+//
+// b If any strong type (either L or R) matching the embedding direction is
+// found, set the type for both brackets in the pair to match the embedding
+// direction.
+//
+// o [ e ] o -> o e e e o
+//
+// o [ o e ] -> o e o e e
+//
+// o [ NI e ] -> o e NI e e
+//
+// c Otherwise, if a strong type (opposite the embedding direction) is
+// found, test for adjacent strong types as follows: 1 First, check
+// backwards before the opening paired bracket until the first strong type
+// (L, R, or sos) is found. If that first preceding strong type is opposite
+// the embedding direction, then set the type for both brackets in the pair
+// to that type. 2 Otherwise, set the type for both brackets in the pair to
+// the embedding direction.
+//
+// o [ o ] e -> o o o o e
+//
+// o [ o NI ] o -> o o o NI o o
+//
+// e [ o ] o -> e e o e o
+//
+// e [ o ] e -> e e o e e
+//
+// e ( o [ o ] NI ) e -> e e o o o o NI e e
+//
+// d Otherwise, do not set the type for the current bracket pair. Note that
+// if the enclosed text contains no strong types the paired brackets will
+// both resolve to the same level when resolved individually using rules N1
+// and N2.
+//
+// e ( NI ) o -> e ( NI ) o
+
+// getStrongTypeN0 maps character's directional code to strong type as required
+// by rule N0.
+//
+// TODO: have separate type for "strong" directionality.
+func (p *bracketPairer) getStrongTypeN0(index int) Class {
+	switch p.codesIsolatedRun[index] {
+	// in the scope of N0, number types are treated as R
+	case EN, AN, AL, R:
+		return R
+	case L:
+		return L
+	default:
+		return ON
+	}
+}
+
+// classifyPairContent reports the strong types contained inside a Bracket Pair,
+// assuming the given embedding direction.
+//
+// It returns ON if no strong type is found. If a single strong type is found,
+// it returns this this type. Otherwise it returns the embedding direction.
+//
+// TODO: use separate type for "strong" directionality.
+func (p *bracketPairer) classifyPairContent(loc bracketPair, dirEmbed Class) Class {
+	dirOpposite := ON
+	for i := loc.opener + 1; i < loc.closer; i++ {
+		dir := p.getStrongTypeN0(i)
+		if dir == ON {
+			continue
+		}
+		if dir == dirEmbed {
+			return dir // type matching embedding direction found
+		}
+		dirOpposite = dir
+	}
+	// return ON if no strong type found, or class opposite to dirEmbed
+	return dirOpposite
+}
+
+// classBeforePair determines which strong types are present before a Bracket
+// Pair. Return R or L if strong type found, otherwise ON.
+func (p *bracketPairer) classBeforePair(loc bracketPair) Class {
+	for i := loc.opener - 1; i >= 0; i-- {
+		if dir := p.getStrongTypeN0(i); dir != ON {
+			return dir
+		}
+	}
+	// no strong types found, return sos
+	return p.sos
+}
+
+// assignBracketType implements rule N0 for a single bracket pair.
+func (p *bracketPairer) assignBracketType(loc bracketPair, dirEmbed Class, initialTypes []Class) {
+	// rule "N0, a", inspect contents of pair
+	dirPair := p.classifyPairContent(loc, dirEmbed)
+
+	// dirPair is now L, R, or N (no strong type found)
+
+	// the following logical tests are performed out of order compared to
+	// the statement of the rules but yield the same results
+	if dirPair == ON {
+		return // case "d" - nothing to do
+	}
+
+	if dirPair != dirEmbed {
+		// case "c": strong type found, opposite - check before (c.1)
+		dirPair = p.classBeforePair(loc)
+		if dirPair == dirEmbed || dirPair == ON {
+			// no strong opposite type found before - use embedding (c.2)
+			dirPair = dirEmbed
+		}
+	}
+	// else: case "b", strong type found matching embedding,
+	// no explicit action needed, as dirPair is already set to embedding
+	// direction
+
+	// set the bracket types to the type found
+	p.setBracketsToType(loc, dirPair, initialTypes)
+}
+
+func (p *bracketPairer) setBracketsToType(loc bracketPair, dirPair Class, initialTypes []Class) {
+	p.codesIsolatedRun[loc.opener] = dirPair
+	p.codesIsolatedRun[loc.closer] = dirPair
+
+	for i := loc.opener + 1; i < loc.closer; i++ {
+		index := p.indexes[i]
+		if initialTypes[index] != NSM {
+			break
+		}
+		p.codesIsolatedRun[i] = dirPair
+	}
+
+	for i := loc.closer + 1; i < len(p.indexes); i++ {
+		index := p.indexes[i]
+		if initialTypes[index] != NSM {
+			break
+		}
+		p.codesIsolatedRun[i] = dirPair
+	}
+}
+
+// resolveBrackets implements rule N0 for a list of pairs.
+func (p *bracketPairer) resolveBrackets(dirEmbed Class, initialTypes []Class) {
+	for _, loc := range p.pairPositions {
+		p.assignBracketType(loc, dirEmbed, initialTypes)
+	}
+}
diff --git a/libgo/go/golang_org/x/text/unicode/bidi/core.go b/libgo/go/golang_org/x/text/unicode/bidi/core.go
new file mode 100644
index 0000000..a352ad6
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/bidi/core.go
@@ -0,0 +1,1060 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bidi
+
+import "log"
+
+// This implementation is a port based on the reference implementation found at:
+// http://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/
+//
+// described in Unicode Bidirectional Algorithm (UAX #9).
+//
+// Input:
+// There are two levels of input to the algorithm, since clients may prefer to
+// supply some information from out-of-band sources rather than relying on the
+// default behavior.
+//
+// - Bidi class array
+// - Bidi class array, with externally supplied base line direction
+//
+// Output:
+// Output is separated into several stages:
+//
+//  - levels array over entire paragraph
+//  - reordering array over entire paragraph
+//  - levels array over line
+//  - reordering array over line
+//
+// Note that for conformance to the Unicode Bidirectional Algorithm,
+// implementations are only required to generate correct reordering and
+// character directionality (odd or even levels) over a line. Generating
+// identical level arrays over a line is not required. Bidi explicit format
+// codes (LRE, RLE, LRO, RLO, PDF) and BN can be assigned arbitrary levels and
+// positions as long as the rest of the input is properly reordered.
+//
+// As the algorithm is defined to operate on a single paragraph at a time, this
+// implementation is written to handle single paragraphs. Thus rule P1 is
+// presumed by this implementation-- the data provided to the implementation is
+// assumed to be a single paragraph, and either contains no 'B' codes, or a
+// single 'B' code at the end of the input. 'B' is allowed as input to
+// illustrate how the algorithm assigns it a level.
+//
+// Also note that rules L3 and L4 depend on the rendering engine that uses the
+// result of the bidi algorithm. This implementation assumes that the rendering
+// engine expects combining marks in visual order (e.g. to the left of their
+// base character in RTL runs) and that it adjusts the glyphs used to render
+// mirrored characters that are in RTL runs so that they render appropriately.
+
+// level is the embedding level of a character. Even embedding levels indicate
+// left-to-right order and odd levels indicate right-to-left order. The special
+// level of -1 is reserved for undefined order.
+type level int8
+
+const implicitLevel level = -1
+
+// in returns if x is equal to any of the values in set.
+func (c Class) in(set ...Class) bool {
+	for _, s := range set {
+		if c == s {
+			return true
+		}
+	}
+	return false
+}
+
+// A paragraph contains the state of a paragraph.
+type paragraph struct {
+	initialTypes []Class
+
+	// Arrays of properties needed for paired bracket evaluation in N0
+	pairTypes  []bracketType // paired Bracket types for paragraph
+	pairValues []rune        // rune for opening bracket or pbOpen and pbClose; 0 for pbNone
+
+	embeddingLevel level // default: = implicitLevel;
+
+	// at the paragraph levels
+	resultTypes  []Class
+	resultLevels []level
+
+	// Index of matching PDI for isolate initiator characters. For other
+	// characters, the value of matchingPDI will be set to -1. For isolate
+	// initiators with no matching PDI, matchingPDI will be set to the length of
+	// the input string.
+	matchingPDI []int
+
+	// Index of matching isolate initiator for PDI characters. For other
+	// characters, and for PDIs with no matching isolate initiator, the value of
+	// matchingIsolateInitiator will be set to -1.
+	matchingIsolateInitiator []int
+}
+
+// newParagraph initializes a paragraph. The user needs to supply a few arrays
+// corresponding to the preprocessed text input. The types correspond to the
+// Unicode BiDi classes for each rune. pairTypes indicates the bracket type for
+// each rune. pairValues provides a unique bracket class identifier for each
+// rune (suggested is the rune of the open bracket for opening and matching
+// close brackets, after normalization). The embedding levels are optional, but
+// may be supplied to encode embedding levels of styled text.
+//
+// TODO: return an error.
+func newParagraph(types []Class, pairTypes []bracketType, pairValues []rune, levels level) *paragraph {
+	validateTypes(types)
+	validatePbTypes(pairTypes)
+	validatePbValues(pairValues, pairTypes)
+	validateParagraphEmbeddingLevel(levels)
+
+	p := &paragraph{
+		initialTypes:   append([]Class(nil), types...),
+		embeddingLevel: levels,
+
+		pairTypes:  pairTypes,
+		pairValues: pairValues,
+
+		resultTypes: append([]Class(nil), types...),
+	}
+	p.run()
+	return p
+}
+
+func (p *paragraph) Len() int { return len(p.initialTypes) }
+
+// The algorithm. Does not include line-based processing (Rules L1, L2).
+// These are applied later in the line-based phase of the algorithm.
+func (p *paragraph) run() {
+	p.determineMatchingIsolates()
+
+	// 1) determining the paragraph level
+	// Rule P1 is the requirement for entering this algorithm.
+	// Rules P2, P3.
+	// If no externally supplied paragraph embedding level, use default.
+	if p.embeddingLevel == implicitLevel {
+		p.embeddingLevel = p.determineParagraphEmbeddingLevel(0, p.Len())
+	}
+
+	// Initialize result levels to paragraph embedding level.
+	p.resultLevels = make([]level, p.Len())
+	setLevels(p.resultLevels, p.embeddingLevel)
+
+	// 2) Explicit levels and directions
+	// Rules X1-X8.
+	p.determineExplicitEmbeddingLevels()
+
+	// Rule X9.
+	// We do not remove the embeddings, the overrides, the PDFs, and the BNs
+	// from the string explicitly. But they are not copied into isolating run
+	// sequences when they are created, so they are removed for all
+	// practical purposes.
+
+	// Rule X10.
+	// Run remainder of algorithm one isolating run sequence at a time
+	for _, seq := range p.determineIsolatingRunSequences() {
+		// 3) resolving weak types
+		// Rules W1-W7.
+		seq.resolveWeakTypes()
+
+		// 4a) resolving paired brackets
+		// Rule N0
+		resolvePairedBrackets(seq)
+
+		// 4b) resolving neutral types
+		// Rules N1-N3.
+		seq.resolveNeutralTypes()
+
+		// 5) resolving implicit embedding levels
+		// Rules I1, I2.
+		seq.resolveImplicitLevels()
+
+		// Apply the computed levels and types
+		seq.applyLevelsAndTypes()
+	}
+
+	// Assign appropriate levels to 'hide' LREs, RLEs, LROs, RLOs, PDFs, and
+	// BNs. This is for convenience, so the resulting level array will have
+	// a value for every character.
+	p.assignLevelsToCharactersRemovedByX9()
+}
+
+// determineMatchingIsolates determines the matching PDI for each isolate
+// initiator and vice versa.
+//
+// Definition BD9.
+//
+// At the end of this function:
+//
+//  - The member variable matchingPDI is set to point to the index of the
+//    matching PDI character for each isolate initiator character. If there is
+//    no matching PDI, it is set to the length of the input text. For other
+//    characters, it is set to -1.
+//  - The member variable matchingIsolateInitiator is set to point to the
+//    index of the matching isolate initiator character for each PDI character.
+//    If there is no matching isolate initiator, or the character is not a PDI,
+//    it is set to -1.
+func (p *paragraph) determineMatchingIsolates() {
+	p.matchingPDI = make([]int, p.Len())
+	p.matchingIsolateInitiator = make([]int, p.Len())
+
+	for i := range p.matchingIsolateInitiator {
+		p.matchingIsolateInitiator[i] = -1
+	}
+
+	for i := range p.matchingPDI {
+		p.matchingPDI[i] = -1
+
+		if t := p.resultTypes[i]; t.in(LRI, RLI, FSI) {
+			depthCounter := 1
+			for j := i + 1; j < p.Len(); j++ {
+				if u := p.resultTypes[j]; u.in(LRI, RLI, FSI) {
+					depthCounter++
+				} else if u == PDI {
+					if depthCounter--; depthCounter == 0 {
+						p.matchingPDI[i] = j
+						p.matchingIsolateInitiator[j] = i
+						break
+					}
+				}
+			}
+			if p.matchingPDI[i] == -1 {
+				p.matchingPDI[i] = p.Len()
+			}
+		}
+	}
+}
+
+// determineParagraphEmbeddingLevel reports the resolved paragraph direction of
+// the substring limited by the given range [start, end).
+//
+// Determines the paragraph level based on rules P2, P3. This is also used
+// in rule X5c to find if an FSI should resolve to LRI or RLI.
+func (p *paragraph) determineParagraphEmbeddingLevel(start, end int) level {
+	var strongType Class = unknownClass
+
+	// Rule P2.
+	for i := start; i < end; i++ {
+		if t := p.resultTypes[i]; t.in(L, AL, R) {
+			strongType = t
+			break
+		} else if t.in(FSI, LRI, RLI) {
+			i = p.matchingPDI[i] // skip over to the matching PDI
+			if i > end {
+				log.Panic("assert (i <= end)")
+			}
+		}
+	}
+	// Rule P3.
+	switch strongType {
+	case unknownClass: // none found
+		// default embedding level when no strong types found is 0.
+		return 0
+	case L:
+		return 0
+	default: // AL, R
+		return 1
+	}
+}
+
+const maxDepth = 125
+
+// This stack will store the embedding levels and override and isolated
+// statuses
+type directionalStatusStack struct {
+	stackCounter        int
+	embeddingLevelStack [maxDepth + 1]level
+	overrideStatusStack [maxDepth + 1]Class
+	isolateStatusStack  [maxDepth + 1]bool
+}
+
+func (s *directionalStatusStack) empty()     { s.stackCounter = 0 }
+func (s *directionalStatusStack) pop()       { s.stackCounter-- }
+func (s *directionalStatusStack) depth() int { return s.stackCounter }
+
+func (s *directionalStatusStack) push(level level, overrideStatus Class, isolateStatus bool) {
+	s.embeddingLevelStack[s.stackCounter] = level
+	s.overrideStatusStack[s.stackCounter] = overrideStatus
+	s.isolateStatusStack[s.stackCounter] = isolateStatus
+	s.stackCounter++
+}
+
+func (s *directionalStatusStack) lastEmbeddingLevel() level {
+	return s.embeddingLevelStack[s.stackCounter-1]
+}
+
+func (s *directionalStatusStack) lastDirectionalOverrideStatus() Class {
+	return s.overrideStatusStack[s.stackCounter-1]
+}
+
+func (s *directionalStatusStack) lastDirectionalIsolateStatus() bool {
+	return s.isolateStatusStack[s.stackCounter-1]
+}
+
+// Determine explicit levels using rules X1 - X8
+func (p *paragraph) determineExplicitEmbeddingLevels() {
+	var stack directionalStatusStack
+	var overflowIsolateCount, overflowEmbeddingCount, validIsolateCount int
+
+	// Rule X1.
+	stack.push(p.embeddingLevel, ON, false)
+
+	for i, t := range p.resultTypes {
+		// Rules X2, X3, X4, X5, X5a, X5b, X5c
+		switch t {
+		case RLE, LRE, RLO, LRO, RLI, LRI, FSI:
+			isIsolate := t.in(RLI, LRI, FSI)
+			isRTL := t.in(RLE, RLO, RLI)
+
+			// override if this is an FSI that resolves to RLI
+			if t == FSI {
+				isRTL = (p.determineParagraphEmbeddingLevel(i+1, p.matchingPDI[i]) == 1)
+			}
+			if isIsolate {
+				p.resultLevels[i] = stack.lastEmbeddingLevel()
+				if stack.lastDirectionalOverrideStatus() != ON {
+					p.resultTypes[i] = stack.lastDirectionalOverrideStatus()
+				}
+			}
+
+			var newLevel level
+			if isRTL {
+				// least greater odd
+				newLevel = (stack.lastEmbeddingLevel() + 1) | 1
+			} else {
+				// least greater even
+				newLevel = (stack.lastEmbeddingLevel() + 2) &^ 1
+			}
+
+			if newLevel <= maxDepth && overflowIsolateCount == 0 && overflowEmbeddingCount == 0 {
+				if isIsolate {
+					validIsolateCount++
+				}
+				// Push new embedding level, override status, and isolated
+				// status.
+				// No check for valid stack counter, since the level check
+				// suffices.
+				switch t {
+				case LRO:
+					stack.push(newLevel, L, isIsolate)
+				case RLO:
+					stack.push(newLevel, R, isIsolate)
+				default:
+					stack.push(newLevel, ON, isIsolate)
+				}
+				// Not really part of the spec
+				if !isIsolate {
+					p.resultLevels[i] = newLevel
+				}
+			} else {
+				// This is an invalid explicit formatting character,
+				// so apply the "Otherwise" part of rules X2-X5b.
+				if isIsolate {
+					overflowIsolateCount++
+				} else { // !isIsolate
+					if overflowIsolateCount == 0 {
+						overflowEmbeddingCount++
+					}
+				}
+			}
+
+		// Rule X6a
+		case PDI:
+			if overflowIsolateCount > 0 {
+				overflowIsolateCount--
+			} else if validIsolateCount == 0 {
+				// do nothing
+			} else {
+				overflowEmbeddingCount = 0
+				for !stack.lastDirectionalIsolateStatus() {
+					stack.pop()
+				}
+				stack.pop()
+				validIsolateCount--
+			}
+			p.resultLevels[i] = stack.lastEmbeddingLevel()
+
+		// Rule X7
+		case PDF:
+			// Not really part of the spec
+			p.resultLevels[i] = stack.lastEmbeddingLevel()
+
+			if overflowIsolateCount > 0 {
+				// do nothing
+			} else if overflowEmbeddingCount > 0 {
+				overflowEmbeddingCount--
+			} else if !stack.lastDirectionalIsolateStatus() && stack.depth() >= 2 {
+				stack.pop()
+			}
+
+		case B: // paragraph separator.
+			// Rule X8.
+
+			// These values are reset for clarity, in this implementation B
+			// can only occur as the last code in the array.
+			stack.empty()
+			overflowIsolateCount = 0
+			overflowEmbeddingCount = 0
+			validIsolateCount = 0
+			p.resultLevels[i] = p.embeddingLevel
+
+		default:
+			p.resultLevels[i] = stack.lastEmbeddingLevel()
+			if stack.lastDirectionalOverrideStatus() != ON {
+				p.resultTypes[i] = stack.lastDirectionalOverrideStatus()
+			}
+		}
+	}
+}
+
+type isolatingRunSequence struct {
+	p *paragraph
+
+	indexes []int // indexes to the original string
+
+	types          []Class // type of each character using the index
+	resolvedLevels []level // resolved levels after application of rules
+	level          level
+	sos, eos       Class
+}
+
+func (i *isolatingRunSequence) Len() int { return len(i.indexes) }
+
+func maxLevel(a, b level) level {
+	if a > b {
+		return a
+	}
+	return b
+}
+
+// Rule X10, second bullet: Determine the start-of-sequence (sos) and end-of-sequence (eos) types,
+// 			 either L or R, for each isolating run sequence.
+func (p *paragraph) isolatingRunSequence(indexes []int) *isolatingRunSequence {
+	length := len(indexes)
+	types := make([]Class, length)
+	for i, x := range indexes {
+		types[i] = p.resultTypes[x]
+	}
+
+	// assign level, sos and eos
+	prevChar := indexes[0] - 1
+	for prevChar >= 0 && isRemovedByX9(p.initialTypes[prevChar]) {
+		prevChar--
+	}
+	prevLevel := p.embeddingLevel
+	if prevChar >= 0 {
+		prevLevel = p.resultLevels[prevChar]
+	}
+
+	var succLevel level
+	lastType := types[length-1]
+	if lastType.in(LRI, RLI, FSI) {
+		succLevel = p.embeddingLevel
+	} else {
+		// the first character after the end of run sequence
+		limit := indexes[length-1] + 1
+		for ; limit < p.Len() && isRemovedByX9(p.initialTypes[limit]); limit++ {
+
+		}
+		succLevel = p.embeddingLevel
+		if limit < p.Len() {
+			succLevel = p.resultLevels[limit]
+		}
+	}
+	level := p.resultLevels[indexes[0]]
+	return &isolatingRunSequence{
+		p:       p,
+		indexes: indexes,
+		types:   types,
+		level:   level,
+		sos:     typeForLevel(maxLevel(prevLevel, level)),
+		eos:     typeForLevel(maxLevel(succLevel, level)),
+	}
+}
+
+// Resolving weak types Rules W1-W7.
+//
+// Note that some weak types (EN, AN) remain after this processing is
+// complete.
+func (s *isolatingRunSequence) resolveWeakTypes() {
+
+	// on entry, only these types remain
+	s.assertOnly(L, R, AL, EN, ES, ET, AN, CS, B, S, WS, ON, NSM, LRI, RLI, FSI, PDI)
+
+	// Rule W1.
+	// Changes all NSMs.
+	preceedingCharacterType := s.sos
+	for i, t := range s.types {
+		if t == NSM {
+			s.types[i] = preceedingCharacterType
+		} else {
+			if t.in(LRI, RLI, FSI, PDI) {
+				preceedingCharacterType = ON
+			}
+			preceedingCharacterType = t
+		}
+	}
+
+	// Rule W2.
+	// EN does not change at the start of the run, because sos != AL.
+	for i, t := range s.types {
+		if t == EN {
+			for j := i - 1; j >= 0; j-- {
+				if t := s.types[j]; t.in(L, R, AL) {
+					if t == AL {
+						s.types[i] = AN
+					}
+					break
+				}
+			}
+		}
+	}
+
+	// Rule W3.
+	for i, t := range s.types {
+		if t == AL {
+			s.types[i] = R
+		}
+	}
+
+	// Rule W4.
+	// Since there must be values on both sides for this rule to have an
+	// effect, the scan skips the first and last value.
+	//
+	// Although the scan proceeds left to right, and changes the type
+	// values in a way that would appear to affect the computations
+	// later in the scan, there is actually no problem. A change in the
+	// current value can only affect the value to its immediate right,
+	// and only affect it if it is ES or CS. But the current value can
+	// only change if the value to its right is not ES or CS. Thus
+	// either the current value will not change, or its change will have
+	// no effect on the remainder of the analysis.
+
+	for i := 1; i < s.Len()-1; i++ {
+		t := s.types[i]
+		if t == ES || t == CS {
+			prevSepType := s.types[i-1]
+			succSepType := s.types[i+1]
+			if prevSepType == EN && succSepType == EN {
+				s.types[i] = EN
+			} else if s.types[i] == CS && prevSepType == AN && succSepType == AN {
+				s.types[i] = AN
+			}
+		}
+	}
+
+	// Rule W5.
+	for i, t := range s.types {
+		if t == ET {
+			// locate end of sequence
+			runStart := i
+			runEnd := s.findRunLimit(runStart, ET)
+
+			// check values at ends of sequence
+			t := s.sos
+			if runStart > 0 {
+				t = s.types[runStart-1]
+			}
+			if t != EN {
+				t = s.eos
+				if runEnd < len(s.types) {
+					t = s.types[runEnd]
+				}
+			}
+			if t == EN {
+				setTypes(s.types[runStart:runEnd], EN)
+			}
+			// continue at end of sequence
+			i = runEnd
+		}
+	}
+
+	// Rule W6.
+	for i, t := range s.types {
+		if t.in(ES, ET, CS) {
+			s.types[i] = ON
+		}
+	}
+
+	// Rule W7.
+	for i, t := range s.types {
+		if t == EN {
+			// set default if we reach start of run
+			prevStrongType := s.sos
+			for j := i - 1; j >= 0; j-- {
+				t = s.types[j]
+				if t == L || t == R { // AL's have been changed to R
+					prevStrongType = t
+					break
+				}
+			}
+			if prevStrongType == L {
+				s.types[i] = L
+			}
+		}
+	}
+}
+
+// 6) resolving neutral types Rules N1-N2.
+func (s *isolatingRunSequence) resolveNeutralTypes() {
+
+	// on entry, only these types can be in resultTypes
+	s.assertOnly(L, R, EN, AN, B, S, WS, ON, RLI, LRI, FSI, PDI)
+
+	for i, t := range s.types {
+		switch t {
+		case WS, ON, B, S, RLI, LRI, FSI, PDI:
+			// find bounds of run of neutrals
+			runStart := i
+			runEnd := s.findRunLimit(runStart, B, S, WS, ON, RLI, LRI, FSI, PDI)
+
+			// determine effective types at ends of run
+			var leadType, trailType Class
+
+			// Note that the character found can only be L, R, AN, or
+			// EN.
+			if runStart == 0 {
+				leadType = s.sos
+			} else {
+				leadType = s.types[runStart-1]
+				if leadType.in(AN, EN) {
+					leadType = R
+				}
+			}
+			if runEnd == len(s.types) {
+				trailType = s.eos
+			} else {
+				trailType = s.types[runEnd]
+				if trailType.in(AN, EN) {
+					trailType = R
+				}
+			}
+
+			var resolvedType Class
+			if leadType == trailType {
+				// Rule N1.
+				resolvedType = leadType
+			} else {
+				// Rule N2.
+				// Notice the embedding level of the run is used, not
+				// the paragraph embedding level.
+				resolvedType = typeForLevel(s.level)
+			}
+
+			setTypes(s.types[runStart:runEnd], resolvedType)
+
+			// skip over run of (former) neutrals
+			i = runEnd
+		}
+	}
+}
+
+func setLevels(levels []level, newLevel level) {
+	for i := range levels {
+		levels[i] = newLevel
+	}
+}
+
+func setTypes(types []Class, newType Class) {
+	for i := range types {
+		types[i] = newType
+	}
+}
+
+// 7) resolving implicit embedding levels Rules I1, I2.
+func (s *isolatingRunSequence) resolveImplicitLevels() {
+
+	// on entry, only these types can be in resultTypes
+	s.assertOnly(L, R, EN, AN)
+
+	s.resolvedLevels = make([]level, len(s.types))
+	setLevels(s.resolvedLevels, s.level)
+
+	if (s.level & 1) == 0 { // even level
+		for i, t := range s.types {
+			// Rule I1.
+			if t == L {
+				// no change
+			} else if t == R {
+				s.resolvedLevels[i] += 1
+			} else { // t == AN || t == EN
+				s.resolvedLevels[i] += 2
+			}
+		}
+	} else { // odd level
+		for i, t := range s.types {
+			// Rule I2.
+			if t == R {
+				// no change
+			} else { // t == L || t == AN || t == EN
+				s.resolvedLevels[i] += 1
+			}
+		}
+	}
+}
+
+// Applies the levels and types resolved in rules W1-I2 to the
+// resultLevels array.
+func (s *isolatingRunSequence) applyLevelsAndTypes() {
+	for i, x := range s.indexes {
+		s.p.resultTypes[x] = s.types[i]
+		s.p.resultLevels[x] = s.resolvedLevels[i]
+	}
+}
+
+// Return the limit of the run consisting only of the types in validSet
+// starting at index. This checks the value at index, and will return
+// index if that value is not in validSet.
+func (s *isolatingRunSequence) findRunLimit(index int, validSet ...Class) int {
+loop:
+	for ; index < len(s.types); index++ {
+		t := s.types[index]
+		for _, valid := range validSet {
+			if t == valid {
+				continue loop
+			}
+		}
+		return index // didn't find a match in validSet
+	}
+	return len(s.types)
+}
+
+// Algorithm validation. Assert that all values in types are in the
+// provided set.
+func (s *isolatingRunSequence) assertOnly(codes ...Class) {
+loop:
+	for i, t := range s.types {
+		for _, c := range codes {
+			if t == c {
+				continue loop
+			}
+		}
+		log.Panicf("invalid bidi code %v present in assertOnly at position %d", t, s.indexes[i])
+	}
+}
+
+// determineLevelRuns returns an array of level runs. Each level run is
+// described as an array of indexes into the input string.
+//
+// Determines the level runs. Rule X9 will be applied in determining the
+// runs, in the way that makes sure the characters that are supposed to be
+// removed are not included in the runs.
+func (p *paragraph) determineLevelRuns() [][]int {
+	run := []int{}
+	allRuns := [][]int{}
+	currentLevel := implicitLevel
+
+	for i := range p.initialTypes {
+		if !isRemovedByX9(p.initialTypes[i]) {
+			if p.resultLevels[i] != currentLevel {
+				// we just encountered a new run; wrap up last run
+				if currentLevel >= 0 { // only wrap it up if there was a run
+					allRuns = append(allRuns, run)
+					run = nil
+				}
+				// Start new run
+				currentLevel = p.resultLevels[i]
+			}
+			run = append(run, i)
+		}
+	}
+	// Wrap up the final run, if any
+	if len(run) > 0 {
+		allRuns = append(allRuns, run)
+	}
+	return allRuns
+}
+
+// Definition BD13. Determine isolating run sequences.
+func (p *paragraph) determineIsolatingRunSequences() []*isolatingRunSequence {
+	levelRuns := p.determineLevelRuns()
+
+	// Compute the run that each character belongs to
+	runForCharacter := make([]int, p.Len())
+	for i, run := range levelRuns {
+		for _, index := range run {
+			runForCharacter[index] = i
+		}
+	}
+
+	sequences := []*isolatingRunSequence{}
+
+	var currentRunSequence []int
+
+	for _, run := range levelRuns {
+		first := run[0]
+		if p.initialTypes[first] != PDI || p.matchingIsolateInitiator[first] == -1 {
+			currentRunSequence = nil
+			// int run = i;
+			for {
+				// Copy this level run into currentRunSequence
+				currentRunSequence = append(currentRunSequence, run...)
+
+				last := currentRunSequence[len(currentRunSequence)-1]
+				lastT := p.initialTypes[last]
+				if lastT.in(LRI, RLI, FSI) && p.matchingPDI[last] != p.Len() {
+					run = levelRuns[runForCharacter[p.matchingPDI[last]]]
+				} else {
+					break
+				}
+			}
+			sequences = append(sequences, p.isolatingRunSequence(currentRunSequence))
+		}
+	}
+	return sequences
+}
+
+// Assign level information to characters removed by rule X9. This is for
+// ease of relating the level information to the original input data. Note
+// that the levels assigned to these codes are arbitrary, they're chosen so
+// as to avoid breaking level runs.
+func (p *paragraph) assignLevelsToCharactersRemovedByX9() {
+	for i, t := range p.initialTypes {
+		if t.in(LRE, RLE, LRO, RLO, PDF, BN) {
+			p.resultTypes[i] = t
+			p.resultLevels[i] = -1
+		}
+	}
+	// now propagate forward the levels information (could have
+	// propagated backward, the main thing is not to introduce a level
+	// break where one doesn't already exist).
+
+	if p.resultLevels[0] == -1 {
+		p.resultLevels[0] = p.embeddingLevel
+	}
+	for i := 1; i < len(p.initialTypes); i++ {
+		if p.resultLevels[i] == -1 {
+			p.resultLevels[i] = p.resultLevels[i-1]
+		}
+	}
+	// Embedding information is for informational purposes only so need not be
+	// adjusted.
+}
+
+//
+// Output
+//
+
+// getLevels computes levels array breaking lines at offsets in linebreaks.
+// Rule L1.
+//
+// The linebreaks array must include at least one value. The values must be
+// in strictly increasing order (no duplicates) between 1 and the length of
+// the text, inclusive. The last value must be the length of the text.
+func (p *paragraph) getLevels(linebreaks []int) []level {
+	// Note that since the previous processing has removed all
+	// P, S, and WS values from resultTypes, the values referred to
+	// in these rules are the initial types, before any processing
+	// has been applied (including processing of overrides).
+	//
+	// This example implementation has reinserted explicit format codes
+	// and BN, in order that the levels array correspond to the
+	// initial text. Their final placement is not normative.
+	// These codes are treated like WS in this implementation,
+	// so they don't interrupt sequences of WS.
+
+	validateLineBreaks(linebreaks, p.Len())
+
+	result := append([]level(nil), p.resultLevels...)
+
+	// don't worry about linebreaks since if there is a break within
+	// a series of WS values preceding S, the linebreak itself
+	// causes the reset.
+	for i, t := range p.initialTypes {
+		if t.in(B, S) {
+			// Rule L1, clauses one and two.
+			result[i] = p.embeddingLevel
+
+			// Rule L1, clause three.
+			for j := i - 1; j >= 0; j-- {
+				if isWhitespace(p.initialTypes[j]) { // including format codes
+					result[j] = p.embeddingLevel
+				} else {
+					break
+				}
+			}
+		}
+	}
+
+	// Rule L1, clause four.
+	start := 0
+	for _, limit := range linebreaks {
+		for j := limit - 1; j >= start; j-- {
+			if isWhitespace(p.initialTypes[j]) { // including format codes
+				result[j] = p.embeddingLevel
+			} else {
+				break
+			}
+		}
+		start = limit
+	}
+
+	return result
+}
+
+// getReordering returns the reordering of lines from a visual index to a
+// logical index for line breaks at the given offsets.
+//
+// Lines are concatenated from left to right. So for example, the fifth
+// character from the left on the third line is
+//
+// 		getReordering(linebreaks)[linebreaks[1] + 4]
+//
+// (linebreaks[1] is the position after the last character of the second
+// line, which is also the index of the first character on the third line,
+// and adding four gets the fifth character from the left).
+//
+// The linebreaks array must include at least one value. The values must be
+// in strictly increasing order (no duplicates) between 1 and the length of
+// the text, inclusive. The last value must be the length of the text.
+func (p *paragraph) getReordering(linebreaks []int) []int {
+	validateLineBreaks(linebreaks, p.Len())
+
+	return computeMultilineReordering(p.getLevels(linebreaks), linebreaks)
+}
+
+// Return multiline reordering array for a given level array. Reordering
+// does not occur across a line break.
+func computeMultilineReordering(levels []level, linebreaks []int) []int {
+	result := make([]int, len(levels))
+
+	start := 0
+	for _, limit := range linebreaks {
+		tempLevels := make([]level, limit-start)
+		copy(tempLevels, levels[start:])
+
+		for j, order := range computeReordering(tempLevels) {
+			result[start+j] = order + start
+		}
+		start = limit
+	}
+	return result
+}
+
+// Return reordering array for a given level array. This reorders a single
+// line. The reordering is a visual to logical map. For example, the
+// leftmost char is string.charAt(order[0]). Rule L2.
+func computeReordering(levels []level) []int {
+	result := make([]int, len(levels))
+	// initialize order
+	for i := range result {
+		result[i] = i
+	}
+
+	// locate highest level found on line.
+	// Note the rules say text, but no reordering across line bounds is
+	// performed, so this is sufficient.
+	highestLevel := level(0)
+	lowestOddLevel := level(maxDepth + 2)
+	for _, level := range levels {
+		if level > highestLevel {
+			highestLevel = level
+		}
+		if level&1 != 0 && level < lowestOddLevel {
+			lowestOddLevel = level
+		}
+	}
+
+	for level := highestLevel; level >= lowestOddLevel; level-- {
+		for i := 0; i < len(levels); i++ {
+			if levels[i] >= level {
+				// find range of text at or above this level
+				start := i
+				limit := i + 1
+				for limit < len(levels) && levels[limit] >= level {
+					limit++
+				}
+
+				for j, k := start, limit-1; j < k; j, k = j+1, k-1 {
+					result[j], result[k] = result[k], result[j]
+				}
+				// skip to end of level run
+				i = limit
+			}
+		}
+	}
+
+	return result
+}
+
+// isWhitespace reports whether the type is considered a whitespace type for the
+// line break rules.
+func isWhitespace(c Class) bool {
+	switch c {
+	case LRE, RLE, LRO, RLO, PDF, LRI, RLI, FSI, PDI, BN, WS:
+		return true
+	}
+	return false
+}
+
+// isRemovedByX9 reports whether the type is one of the types removed in X9.
+func isRemovedByX9(c Class) bool {
+	switch c {
+	case LRE, RLE, LRO, RLO, PDF, BN:
+		return true
+	}
+	return false
+}
+
+// typeForLevel reports the strong type (L or R) corresponding to the level.
+func typeForLevel(level level) Class {
+	if (level & 0x1) == 0 {
+		return L
+	}
+	return R
+}
+
+// TODO: change validation to not panic
+
+func validateTypes(types []Class) {
+	if len(types) == 0 {
+		log.Panic("types is null")
+	}
+	for i, t := range types[:len(types)-1] {
+		if t == B {
+			log.Panicf("B type before end of paragraph at index: %d", i)
+		}
+	}
+}
+
+func validateParagraphEmbeddingLevel(embeddingLevel level) {
+	if embeddingLevel != implicitLevel &&
+		embeddingLevel != 0 &&
+		embeddingLevel != 1 {
+		log.Panicf("illegal paragraph embedding level: %d", embeddingLevel)
+	}
+}
+
+func validateLineBreaks(linebreaks []int, textLength int) {
+	prev := 0
+	for i, next := range linebreaks {
+		if next <= prev {
+			log.Panicf("bad linebreak: %d at index: %d", next, i)
+		}
+		prev = next
+	}
+	if prev != textLength {
+		log.Panicf("last linebreak was %d, want %d", prev, textLength)
+	}
+}
+
+func validatePbTypes(pairTypes []bracketType) {
+	if len(pairTypes) == 0 {
+		log.Panic("pairTypes is null")
+	}
+	for i, pt := range pairTypes {
+		switch pt {
+		case bpNone, bpOpen, bpClose:
+		default:
+			log.Panicf("illegal pairType value at %d: %v", i, pairTypes[i])
+		}
+	}
+}
+
+func validatePbValues(pairValues []rune, pairTypes []bracketType) {
+	if pairValues == nil {
+		log.Panic("pairValues is null")
+	}
+	if len(pairTypes) != len(pairValues) {
+		log.Panic("pairTypes is different length from pairValues")
+	}
+}
diff --git a/libgo/go/golang_org/x/text/unicode/bidi/example_test.go b/libgo/go/golang_org/x/text/unicode/bidi/example_test.go
new file mode 100644
index 0000000..e173959
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/bidi/example_test.go
@@ -0,0 +1,185 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// +build ignore
+
+package bidi_test
+
+import (
+	"fmt"
+	"log"
+
+	"golang_org/x/text/bidi"
+)
+
+func foo() {
+	var sa StringAttributes
+	var p Paragraph
+	n, _ := p.SetString(s)
+	for i, o := 0, p.Ordering(); i < o.NumRuns(); i++ {
+		b := o.Run(i).Bytes()
+
+		start, end := o.Run(i).Pos()
+		for p := start; p < end; {
+			style, n := sa.StyleAt(start)
+			render()
+			p += n
+		}
+
+	}
+}
+
+type style int
+
+const (
+	styleNormal   = 0
+	styleSelected = 1 << (iota - 1)
+	styleBold
+	styleItalics
+)
+
+type styleRun struct {
+	end   int
+	style style
+}
+
+func getTextWidth(text string, styleRuns []styleRun) int {
+	// simplistic way to compute the width
+	return len([]rune(text))
+}
+
+// set limit and StyleRun limit for a line
+// from text[start] and from styleRuns[styleRunStart]
+// using Bidi.getLogicalRun(...)
+// returns line width
+func getLineBreak(p *bidi.Paragraph, start int, styles []styleRun) (n int) {
+	// dummy return
+	return 0
+}
+
+// render runs on a line sequentially, always from left to right
+
+// prepare rendering a new line
+func startLine(d bidi.Direction, lineWidth int) {
+	fmt.Println()
+}
+
+// render a run of text and advance to the right by the run width
+// the text[start..limit-1] is always in logical order
+func renderRun(text string, d bidi.Direction, styl style) {
+}
+
+// We could compute a cross-product
+// from the style runs with the directional runs
+// and then reorder it.
+// Instead, here we iterate over each run type
+// and render the intersections -
+// with shortcuts in simple (and common) cases.
+// renderParagraph() is the main function.
+
+// render a directional run with
+// (possibly) multiple style runs intersecting with it
+func renderDirectionalRun(text string, offset int, d bidi.Direction, styles []styleRun) {
+	start, end := offset, len(text)+offset
+	// iterate over style runs
+	if run.Direction() == bidi.LeftToRight {
+		styleEnd := 0
+		for _, sr := range styles {
+			styleEnd = styleRuns[i].end
+			if start < styleEnd {
+				if styleEnd > end {
+					styleEnd = end
+				}
+				renderRun(text[start-offset:styleEnd-offset], run.Direction(), styles[i].style)
+				if styleEnd == end {
+					break
+				}
+				start = styleEnd
+			}
+		}
+	} else {
+		styleStart := 0
+		for i := len(styles) - 1; i >= 0; i-- {
+			if i > 0 {
+				styleStart = styles[i-1].end
+			} else {
+				styleStart = 0
+			}
+			if end >= styleStart {
+				if styleStart < start {
+					styleStart = start
+				}
+				renderRun(text[styleStart-offset:end-offset], run.Direction(), styles[i].style)
+				if styleStart == start {
+					break
+				}
+				end = styleStart
+			}
+		}
+	}
+}
+
+// the line object represents text[start..limit-1]
+func renderLine(line *bidi.Runs, text string, offset int, styles []styleRun) {
+	if dir := line.Direction(); dir != bidi.Mixed {
+		if len(styles) == 1 {
+			renderRun(text, dir, styles[0].style)
+		} else {
+			for i := 0; i < line.NumRuns(); i++ {
+				renderDirectionalRun(text, offset, dir, styles)
+			}
+		}
+	} else {
+		// iterate over both directional and style runs
+		for i := 0; i < line.Len(); i++ {
+			run := line.Run(i)
+			start, _ := run.Pos()
+			renderDirectionalRun(text[start-offset:], start, run.Direction(), styles)
+		}
+	}
+}
+
+func renderParagraph(text string, d bidi.Direction, styles []styleRun, int lineWidth) {
+	var p bidi.Paragraph
+	if err := p.SetString(text, bidi.DefaultDirection(d)); err != nil {
+		log.Fatal(err)
+	}
+
+	if len(styles) == 0 {
+		styles = append(styles, []styleRun{len(text), styleNormal})
+	}
+
+	if width := getTextWidth(text, styles); width <= lineWidth {
+		// everything fits onto one line
+
+		runs, err := p.Runs()
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		// prepare rendering a new line from either left or right
+		startLine(p.Direction(), width)
+		renderLine(&runs, text, styles)
+	} else {
+		// we need to render several lines
+
+		for start, end := 0, 0; start < len(text); start = end {
+			for start >= styles[0].end {
+				styles = styles[1:]
+			}
+			end = getLineBreak(p, start, styles[startStyles:])
+
+			runs, err := p.Line(start, end)
+			if err != nil {
+				log.Fatal(err)
+			}
+
+			startLine(p.Direction(), end-start)
+			renderLine(&runs, text[start:end], styles[startStyles:])
+		}
+	}
+}
+
+func main() {
+	renderParagraph("Some Latin text...", bidi.LeftToRight, nil, 80)
+	renderParagraph("Some Hebrew text...", bidi.RightToLeft, nil, 60)
+}
diff --git a/libgo/go/golang_org/x/text/unicode/bidi/prop.go b/libgo/go/golang_org/x/text/unicode/bidi/prop.go
new file mode 100644
index 0000000..ed191c2
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/bidi/prop.go
@@ -0,0 +1,208 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bidi
+
+import "unicode/utf8"
+
+// Properties provides access to BiDi properties of runes.
+type Properties struct {
+	entry uint8
+	last  uint8
+}
+
+var trie = newBidiTrie(0)
+
+// TODO: using this for bidirule reduces the running time by about 5%. Consider
+// if this is worth exposing or if we can find a way to speed up the Class
+// method.
+//
+// // CompactClass is like Class, but maps all of the BiDi control classes
+// // (LRO, RLO, LRE, RLE, PDF, LRI, RLI, FSI, PDI) to the class Control.
+// func (p Properties) CompactClass() Class {
+// 	return Class(p.entry & 0x0F)
+// }
+
+// Class returns the Bidi class for p.
+func (p Properties) Class() Class {
+	c := Class(p.entry & 0x0F)
+	if c == Control {
+		c = controlByteToClass[p.last&0xF]
+	}
+	return c
+}
+
+// IsBracket reports whether the rune is a bracket.
+func (p Properties) IsBracket() bool { return p.entry&0xF0 != 0 }
+
+// IsOpeningBracket reports whether the rune is an opening bracket.
+// IsBracket must return true.
+func (p Properties) IsOpeningBracket() bool { return p.entry&openMask != 0 }
+
+// TODO: find a better API and expose.
+func (p Properties) reverseBracket(r rune) rune {
+	return xorMasks[p.entry>>xorMaskShift] ^ r
+}
+
+var controlByteToClass = [16]Class{
+	0xD: LRO, // U+202D LeftToRightOverride,
+	0xE: RLO, // U+202E RightToLeftOverride,
+	0xA: LRE, // U+202A LeftToRightEmbedding,
+	0xB: RLE, // U+202B RightToLeftEmbedding,
+	0xC: PDF, // U+202C PopDirectionalFormat,
+	0x6: LRI, // U+2066 LeftToRightIsolate,
+	0x7: RLI, // U+2067 RightToLeftIsolate,
+	0x8: FSI, // U+2068 FirstStrongIsolate,
+	0x9: PDI, // U+2069 PopDirectionalIsolate,
+}
+
+// LookupRune returns properties for r.
+func LookupRune(r rune) (p Properties, size int) {
+	var buf [4]byte
+	n := utf8.EncodeRune(buf[:], r)
+	return Lookup(buf[:n])
+}
+
+// TODO: these lookup methods are based on the generated trie code. The returned
+// sizes have slightly different semantics from the generated code, in that it
+// always returns size==1 for an illegal UTF-8 byte (instead of the length
+// of the maximum invalid subsequence). Most Transformers, like unicode/norm,
+// leave invalid UTF-8 untouched, in which case it has performance benefits to
+// do so (without changing the semantics). Bidi requires the semantics used here
+// for the bidirule implementation to be compatible with the Go semantics.
+//  They ultimately should perhaps be adopted by all trie implementations, for
+// convenience sake.
+// This unrolled code also boosts performance of the secure/bidirule package by
+// about 30%.
+// So, to remove this code:
+//   - add option to trie generator to define return type.
+//   - always return 1 byte size for ill-formed UTF-8 runes.
+
+// Lookup returns properties for the first rune in s and the width in bytes of
+// its encoding. The size will be 0 if s does not hold enough bytes to complete
+// the encoding.
+func Lookup(s []byte) (p Properties, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return Properties{entry: bidiValues[c0]}, 1
+	case c0 < 0xC2:
+		return Properties{}, 1
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c1)}, 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c2), last: c2}, 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = bidiIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c3)}, 4
+	}
+	// Illegal rune
+	return Properties{}, 1
+}
+
+// LookupString returns properties for the first rune in s and the width in
+// bytes of its encoding. The size will be 0 if s does not hold enough bytes to
+// complete the encoding.
+func LookupString(s string) (p Properties, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return Properties{entry: bidiValues[c0]}, 1
+	case c0 < 0xC2:
+		return Properties{}, 1
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c1)}, 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c2), last: c2}, 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = bidiIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c3)}, 4
+	}
+	// Illegal rune
+	return Properties{}, 1
+}
diff --git a/libgo/go/golang_org/x/text/unicode/bidi/tables.go b/libgo/go/golang_org/x/text/unicode/bidi/tables.go
new file mode 100644
index 0000000..1245315
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/bidi/tables.go
@@ -0,0 +1,1781 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Code generated by running "go generate" in golang_org/x/text. DO NOT EDIT.
+
+package bidi
+
+// UnicodeVersion is the Unicode version from which the tables in this package are derived.
+const UnicodeVersion = "9.0.0"
+
+// xorMasks contains masks to be xor-ed with brackets to get the reverse
+// version.
+var xorMasks = []int32{ // 8 elements
+	0, 1, 6, 7, 3, 15, 29, 63,
+} // Size: 56 bytes
+
+// lookup returns the trie value for the first UTF-8 encoding in s and
+// the width in bytes of this encoding. The size will be 0 if s does not
+// hold enough bytes to complete the encoding. len(s) must be greater than 0.
+func (t *bidiTrie) lookup(s []byte) (v uint8, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return bidiValues[c0], 1
+	case c0 < 0xC2:
+		return 0, 1 // Illegal UTF-8: not a starter, not ASCII.
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return 0, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c1), 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return 0, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c2), 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return 0, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = bidiIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return 0, 3 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c3), 4
+	}
+	// Illegal rune
+	return 0, 1
+}
+
+// lookupUnsafe returns the trie value for the first UTF-8 encoding in s.
+// s must start with a full and valid UTF-8 encoded rune.
+func (t *bidiTrie) lookupUnsafe(s []byte) uint8 {
+	c0 := s[0]
+	if c0 < 0x80 { // is ASCII
+		return bidiValues[c0]
+	}
+	i := bidiIndex[c0]
+	if c0 < 0xE0 { // 2-byte UTF-8
+		return t.lookupValue(uint32(i), s[1])
+	}
+	i = bidiIndex[uint32(i)<<6+uint32(s[1])]
+	if c0 < 0xF0 { // 3-byte UTF-8
+		return t.lookupValue(uint32(i), s[2])
+	}
+	i = bidiIndex[uint32(i)<<6+uint32(s[2])]
+	if c0 < 0xF8 { // 4-byte UTF-8
+		return t.lookupValue(uint32(i), s[3])
+	}
+	return 0
+}
+
+// lookupString returns the trie value for the first UTF-8 encoding in s and
+// the width in bytes of this encoding. The size will be 0 if s does not
+// hold enough bytes to complete the encoding. len(s) must be greater than 0.
+func (t *bidiTrie) lookupString(s string) (v uint8, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return bidiValues[c0], 1
+	case c0 < 0xC2:
+		return 0, 1 // Illegal UTF-8: not a starter, not ASCII.
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return 0, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c1), 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return 0, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c2), 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return 0, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return 0, 1 // Illegal UTF-8: not a continuation byte.
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return 0, 2 // Illegal UTF-8: not a continuation byte.
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = bidiIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return 0, 3 // Illegal UTF-8: not a continuation byte.
+		}
+		return t.lookupValue(uint32(i), c3), 4
+	}
+	// Illegal rune
+	return 0, 1
+}
+
+// lookupStringUnsafe returns the trie value for the first UTF-8 encoding in s.
+// s must start with a full and valid UTF-8 encoded rune.
+func (t *bidiTrie) lookupStringUnsafe(s string) uint8 {
+	c0 := s[0]
+	if c0 < 0x80 { // is ASCII
+		return bidiValues[c0]
+	}
+	i := bidiIndex[c0]
+	if c0 < 0xE0 { // 2-byte UTF-8
+		return t.lookupValue(uint32(i), s[1])
+	}
+	i = bidiIndex[uint32(i)<<6+uint32(s[1])]
+	if c0 < 0xF0 { // 3-byte UTF-8
+		return t.lookupValue(uint32(i), s[2])
+	}
+	i = bidiIndex[uint32(i)<<6+uint32(s[2])]
+	if c0 < 0xF8 { // 4-byte UTF-8
+		return t.lookupValue(uint32(i), s[3])
+	}
+	return 0
+}
+
+// bidiTrie. Total size: 15744 bytes (15.38 KiB). Checksum: b4c3b70954803b86.
+type bidiTrie struct{}
+
+func newBidiTrie(i int) *bidiTrie {
+	return &bidiTrie{}
+}
+
+// lookupValue determines the type of block n and looks up the value for b.
+func (t *bidiTrie) lookupValue(n uint32, b byte) uint8 {
+	switch {
+	default:
+		return uint8(bidiValues[n<<6+uint32(b)])
+	}
+}
+
+// bidiValues: 222 blocks, 14208 entries, 14208 bytes
+// The third block is the zero block.
+var bidiValues = [14208]uint8{
+	// Block 0x0, offset 0x0
+	0x00: 0x000b, 0x01: 0x000b, 0x02: 0x000b, 0x03: 0x000b, 0x04: 0x000b, 0x05: 0x000b,
+	0x06: 0x000b, 0x07: 0x000b, 0x08: 0x000b, 0x09: 0x0008, 0x0a: 0x0007, 0x0b: 0x0008,
+	0x0c: 0x0009, 0x0d: 0x0007, 0x0e: 0x000b, 0x0f: 0x000b, 0x10: 0x000b, 0x11: 0x000b,
+	0x12: 0x000b, 0x13: 0x000b, 0x14: 0x000b, 0x15: 0x000b, 0x16: 0x000b, 0x17: 0x000b,
+	0x18: 0x000b, 0x19: 0x000b, 0x1a: 0x000b, 0x1b: 0x000b, 0x1c: 0x0007, 0x1d: 0x0007,
+	0x1e: 0x0007, 0x1f: 0x0008, 0x20: 0x0009, 0x21: 0x000a, 0x22: 0x000a, 0x23: 0x0004,
+	0x24: 0x0004, 0x25: 0x0004, 0x26: 0x000a, 0x27: 0x000a, 0x28: 0x003a, 0x29: 0x002a,
+	0x2a: 0x000a, 0x2b: 0x0003, 0x2c: 0x0006, 0x2d: 0x0003, 0x2e: 0x0006, 0x2f: 0x0006,
+	0x30: 0x0002, 0x31: 0x0002, 0x32: 0x0002, 0x33: 0x0002, 0x34: 0x0002, 0x35: 0x0002,
+	0x36: 0x0002, 0x37: 0x0002, 0x38: 0x0002, 0x39: 0x0002, 0x3a: 0x0006, 0x3b: 0x000a,
+	0x3c: 0x000a, 0x3d: 0x000a, 0x3e: 0x000a, 0x3f: 0x000a,
+	// Block 0x1, offset 0x40
+	0x40: 0x000a,
+	0x5b: 0x005a, 0x5c: 0x000a, 0x5d: 0x004a,
+	0x5e: 0x000a, 0x5f: 0x000a, 0x60: 0x000a,
+	0x7b: 0x005a,
+	0x7c: 0x000a, 0x7d: 0x004a, 0x7e: 0x000a, 0x7f: 0x000b,
+	// Block 0x2, offset 0x80
+	// Block 0x3, offset 0xc0
+	0xc0: 0x000b, 0xc1: 0x000b, 0xc2: 0x000b, 0xc3: 0x000b, 0xc4: 0x000b, 0xc5: 0x0007,
+	0xc6: 0x000b, 0xc7: 0x000b, 0xc8: 0x000b, 0xc9: 0x000b, 0xca: 0x000b, 0xcb: 0x000b,
+	0xcc: 0x000b, 0xcd: 0x000b, 0xce: 0x000b, 0xcf: 0x000b, 0xd0: 0x000b, 0xd1: 0x000b,
+	0xd2: 0x000b, 0xd3: 0x000b, 0xd4: 0x000b, 0xd5: 0x000b, 0xd6: 0x000b, 0xd7: 0x000b,
+	0xd8: 0x000b, 0xd9: 0x000b, 0xda: 0x000b, 0xdb: 0x000b, 0xdc: 0x000b, 0xdd: 0x000b,
+	0xde: 0x000b, 0xdf: 0x000b, 0xe0: 0x0006, 0xe1: 0x000a, 0xe2: 0x0004, 0xe3: 0x0004,
+	0xe4: 0x0004, 0xe5: 0x0004, 0xe6: 0x000a, 0xe7: 0x000a, 0xe8: 0x000a, 0xe9: 0x000a,
+	0xeb: 0x000a, 0xec: 0x000a, 0xed: 0x000b, 0xee: 0x000a, 0xef: 0x000a,
+	0xf0: 0x0004, 0xf1: 0x0004, 0xf2: 0x0002, 0xf3: 0x0002, 0xf4: 0x000a,
+	0xf6: 0x000a, 0xf7: 0x000a, 0xf8: 0x000a, 0xf9: 0x0002, 0xfb: 0x000a,
+	0xfc: 0x000a, 0xfd: 0x000a, 0xfe: 0x000a, 0xff: 0x000a,
+	// Block 0x4, offset 0x100
+	0x117: 0x000a,
+	0x137: 0x000a,
+	// Block 0x5, offset 0x140
+	0x179: 0x000a, 0x17a: 0x000a,
+	// Block 0x6, offset 0x180
+	0x182: 0x000a, 0x183: 0x000a, 0x184: 0x000a, 0x185: 0x000a,
+	0x186: 0x000a, 0x187: 0x000a, 0x188: 0x000a, 0x189: 0x000a, 0x18a: 0x000a, 0x18b: 0x000a,
+	0x18c: 0x000a, 0x18d: 0x000a, 0x18e: 0x000a, 0x18f: 0x000a,
+	0x192: 0x000a, 0x193: 0x000a, 0x194: 0x000a, 0x195: 0x000a, 0x196: 0x000a, 0x197: 0x000a,
+	0x198: 0x000a, 0x199: 0x000a, 0x19a: 0x000a, 0x19b: 0x000a, 0x19c: 0x000a, 0x19d: 0x000a,
+	0x19e: 0x000a, 0x19f: 0x000a,
+	0x1a5: 0x000a, 0x1a6: 0x000a, 0x1a7: 0x000a, 0x1a8: 0x000a, 0x1a9: 0x000a,
+	0x1aa: 0x000a, 0x1ab: 0x000a, 0x1ac: 0x000a, 0x1ad: 0x000a, 0x1af: 0x000a,
+	0x1b0: 0x000a, 0x1b1: 0x000a, 0x1b2: 0x000a, 0x1b3: 0x000a, 0x1b4: 0x000a, 0x1b5: 0x000a,
+	0x1b6: 0x000a, 0x1b7: 0x000a, 0x1b8: 0x000a, 0x1b9: 0x000a, 0x1ba: 0x000a, 0x1bb: 0x000a,
+	0x1bc: 0x000a, 0x1bd: 0x000a, 0x1be: 0x000a, 0x1bf: 0x000a,
+	// Block 0x7, offset 0x1c0
+	0x1c0: 0x000c, 0x1c1: 0x000c, 0x1c2: 0x000c, 0x1c3: 0x000c, 0x1c4: 0x000c, 0x1c5: 0x000c,
+	0x1c6: 0x000c, 0x1c7: 0x000c, 0x1c8: 0x000c, 0x1c9: 0x000c, 0x1ca: 0x000c, 0x1cb: 0x000c,
+	0x1cc: 0x000c, 0x1cd: 0x000c, 0x1ce: 0x000c, 0x1cf: 0x000c, 0x1d0: 0x000c, 0x1d1: 0x000c,
+	0x1d2: 0x000c, 0x1d3: 0x000c, 0x1d4: 0x000c, 0x1d5: 0x000c, 0x1d6: 0x000c, 0x1d7: 0x000c,
+	0x1d8: 0x000c, 0x1d9: 0x000c, 0x1da: 0x000c, 0x1db: 0x000c, 0x1dc: 0x000c, 0x1dd: 0x000c,
+	0x1de: 0x000c, 0x1df: 0x000c, 0x1e0: 0x000c, 0x1e1: 0x000c, 0x1e2: 0x000c, 0x1e3: 0x000c,
+	0x1e4: 0x000c, 0x1e5: 0x000c, 0x1e6: 0x000c, 0x1e7: 0x000c, 0x1e8: 0x000c, 0x1e9: 0x000c,
+	0x1ea: 0x000c, 0x1eb: 0x000c, 0x1ec: 0x000c, 0x1ed: 0x000c, 0x1ee: 0x000c, 0x1ef: 0x000c,
+	0x1f0: 0x000c, 0x1f1: 0x000c, 0x1f2: 0x000c, 0x1f3: 0x000c, 0x1f4: 0x000c, 0x1f5: 0x000c,
+	0x1f6: 0x000c, 0x1f7: 0x000c, 0x1f8: 0x000c, 0x1f9: 0x000c, 0x1fa: 0x000c, 0x1fb: 0x000c,
+	0x1fc: 0x000c, 0x1fd: 0x000c, 0x1fe: 0x000c, 0x1ff: 0x000c,
+	// Block 0x8, offset 0x200
+	0x200: 0x000c, 0x201: 0x000c, 0x202: 0x000c, 0x203: 0x000c, 0x204: 0x000c, 0x205: 0x000c,
+	0x206: 0x000c, 0x207: 0x000c, 0x208: 0x000c, 0x209: 0x000c, 0x20a: 0x000c, 0x20b: 0x000c,
+	0x20c: 0x000c, 0x20d: 0x000c, 0x20e: 0x000c, 0x20f: 0x000c, 0x210: 0x000c, 0x211: 0x000c,
+	0x212: 0x000c, 0x213: 0x000c, 0x214: 0x000c, 0x215: 0x000c, 0x216: 0x000c, 0x217: 0x000c,
+	0x218: 0x000c, 0x219: 0x000c, 0x21a: 0x000c, 0x21b: 0x000c, 0x21c: 0x000c, 0x21d: 0x000c,
+	0x21e: 0x000c, 0x21f: 0x000c, 0x220: 0x000c, 0x221: 0x000c, 0x222: 0x000c, 0x223: 0x000c,
+	0x224: 0x000c, 0x225: 0x000c, 0x226: 0x000c, 0x227: 0x000c, 0x228: 0x000c, 0x229: 0x000c,
+	0x22a: 0x000c, 0x22b: 0x000c, 0x22c: 0x000c, 0x22d: 0x000c, 0x22e: 0x000c, 0x22f: 0x000c,
+	0x234: 0x000a, 0x235: 0x000a,
+	0x23e: 0x000a,
+	// Block 0x9, offset 0x240
+	0x244: 0x000a, 0x245: 0x000a,
+	0x247: 0x000a,
+	// Block 0xa, offset 0x280
+	0x2b6: 0x000a,
+	// Block 0xb, offset 0x2c0
+	0x2c3: 0x000c, 0x2c4: 0x000c, 0x2c5: 0x000c,
+	0x2c6: 0x000c, 0x2c7: 0x000c, 0x2c8: 0x000c, 0x2c9: 0x000c,
+	// Block 0xc, offset 0x300
+	0x30a: 0x000a,
+	0x30d: 0x000a, 0x30e: 0x000a, 0x30f: 0x0004, 0x310: 0x0001, 0x311: 0x000c,
+	0x312: 0x000c, 0x313: 0x000c, 0x314: 0x000c, 0x315: 0x000c, 0x316: 0x000c, 0x317: 0x000c,
+	0x318: 0x000c, 0x319: 0x000c, 0x31a: 0x000c, 0x31b: 0x000c, 0x31c: 0x000c, 0x31d: 0x000c,
+	0x31e: 0x000c, 0x31f: 0x000c, 0x320: 0x000c, 0x321: 0x000c, 0x322: 0x000c, 0x323: 0x000c,
+	0x324: 0x000c, 0x325: 0x000c, 0x326: 0x000c, 0x327: 0x000c, 0x328: 0x000c, 0x329: 0x000c,
+	0x32a: 0x000c, 0x32b: 0x000c, 0x32c: 0x000c, 0x32d: 0x000c, 0x32e: 0x000c, 0x32f: 0x000c,
+	0x330: 0x000c, 0x331: 0x000c, 0x332: 0x000c, 0x333: 0x000c, 0x334: 0x000c, 0x335: 0x000c,
+	0x336: 0x000c, 0x337: 0x000c, 0x338: 0x000c, 0x339: 0x000c, 0x33a: 0x000c, 0x33b: 0x000c,
+	0x33c: 0x000c, 0x33d: 0x000c, 0x33e: 0x0001, 0x33f: 0x000c,
+	// Block 0xd, offset 0x340
+	0x340: 0x0001, 0x341: 0x000c, 0x342: 0x000c, 0x343: 0x0001, 0x344: 0x000c, 0x345: 0x000c,
+	0x346: 0x0001, 0x347: 0x000c, 0x348: 0x0001, 0x349: 0x0001, 0x34a: 0x0001, 0x34b: 0x0001,
+	0x34c: 0x0001, 0x34d: 0x0001, 0x34e: 0x0001, 0x34f: 0x0001, 0x350: 0x0001, 0x351: 0x0001,
+	0x352: 0x0001, 0x353: 0x0001, 0x354: 0x0001, 0x355: 0x0001, 0x356: 0x0001, 0x357: 0x0001,
+	0x358: 0x0001, 0x359: 0x0001, 0x35a: 0x0001, 0x35b: 0x0001, 0x35c: 0x0001, 0x35d: 0x0001,
+	0x35e: 0x0001, 0x35f: 0x0001, 0x360: 0x0001, 0x361: 0x0001, 0x362: 0x0001, 0x363: 0x0001,
+	0x364: 0x0001, 0x365: 0x0001, 0x366: 0x0001, 0x367: 0x0001, 0x368: 0x0001, 0x369: 0x0001,
+	0x36a: 0x0001, 0x36b: 0x0001, 0x36c: 0x0001, 0x36d: 0x0001, 0x36e: 0x0001, 0x36f: 0x0001,
+	0x370: 0x0001, 0x371: 0x0001, 0x372: 0x0001, 0x373: 0x0001, 0x374: 0x0001, 0x375: 0x0001,
+	0x376: 0x0001, 0x377: 0x0001, 0x378: 0x0001, 0x379: 0x0001, 0x37a: 0x0001, 0x37b: 0x0001,
+	0x37c: 0x0001, 0x37d: 0x0001, 0x37e: 0x0001, 0x37f: 0x0001,
+	// Block 0xe, offset 0x380
+	0x380: 0x0005, 0x381: 0x0005, 0x382: 0x0005, 0x383: 0x0005, 0x384: 0x0005, 0x385: 0x0005,
+	0x386: 0x000a, 0x387: 0x000a, 0x388: 0x000d, 0x389: 0x0004, 0x38a: 0x0004, 0x38b: 0x000d,
+	0x38c: 0x0006, 0x38d: 0x000d, 0x38e: 0x000a, 0x38f: 0x000a, 0x390: 0x000c, 0x391: 0x000c,
+	0x392: 0x000c, 0x393: 0x000c, 0x394: 0x000c, 0x395: 0x000c, 0x396: 0x000c, 0x397: 0x000c,
+	0x398: 0x000c, 0x399: 0x000c, 0x39a: 0x000c, 0x39b: 0x000d, 0x39c: 0x000d, 0x39d: 0x000d,
+	0x39e: 0x000d, 0x39f: 0x000d, 0x3a0: 0x000d, 0x3a1: 0x000d, 0x3a2: 0x000d, 0x3a3: 0x000d,
+	0x3a4: 0x000d, 0x3a5: 0x000d, 0x3a6: 0x000d, 0x3a7: 0x000d, 0x3a8: 0x000d, 0x3a9: 0x000d,
+	0x3aa: 0x000d, 0x3ab: 0x000d, 0x3ac: 0x000d, 0x3ad: 0x000d, 0x3ae: 0x000d, 0x3af: 0x000d,
+	0x3b0: 0x000d, 0x3b1: 0x000d, 0x3b2: 0x000d, 0x3b3: 0x000d, 0x3b4: 0x000d, 0x3b5: 0x000d,
+	0x3b6: 0x000d, 0x3b7: 0x000d, 0x3b8: 0x000d, 0x3b9: 0x000d, 0x3ba: 0x000d, 0x3bb: 0x000d,
+	0x3bc: 0x000d, 0x3bd: 0x000d, 0x3be: 0x000d, 0x3bf: 0x000d,
+	// Block 0xf, offset 0x3c0
+	0x3c0: 0x000d, 0x3c1: 0x000d, 0x3c2: 0x000d, 0x3c3: 0x000d, 0x3c4: 0x000d, 0x3c5: 0x000d,
+	0x3c6: 0x000d, 0x3c7: 0x000d, 0x3c8: 0x000d, 0x3c9: 0x000d, 0x3ca: 0x000d, 0x3cb: 0x000c,
+	0x3cc: 0x000c, 0x3cd: 0x000c, 0x3ce: 0x000c, 0x3cf: 0x000c, 0x3d0: 0x000c, 0x3d1: 0x000c,
+	0x3d2: 0x000c, 0x3d3: 0x000c, 0x3d4: 0x000c, 0x3d5: 0x000c, 0x3d6: 0x000c, 0x3d7: 0x000c,
+	0x3d8: 0x000c, 0x3d9: 0x000c, 0x3da: 0x000c, 0x3db: 0x000c, 0x3dc: 0x000c, 0x3dd: 0x000c,
+	0x3de: 0x000c, 0x3df: 0x000c, 0x3e0: 0x0005, 0x3e1: 0x0005, 0x3e2: 0x0005, 0x3e3: 0x0005,
+	0x3e4: 0x0005, 0x3e5: 0x0005, 0x3e6: 0x0005, 0x3e7: 0x0005, 0x3e8: 0x0005, 0x3e9: 0x0005,
+	0x3ea: 0x0004, 0x3eb: 0x0005, 0x3ec: 0x0005, 0x3ed: 0x000d, 0x3ee: 0x000d, 0x3ef: 0x000d,
+	0x3f0: 0x000c, 0x3f1: 0x000d, 0x3f2: 0x000d, 0x3f3: 0x000d, 0x3f4: 0x000d, 0x3f5: 0x000d,
+	0x3f6: 0x000d, 0x3f7: 0x000d, 0x3f8: 0x000d, 0x3f9: 0x000d, 0x3fa: 0x000d, 0x3fb: 0x000d,
+	0x3fc: 0x000d, 0x3fd: 0x000d, 0x3fe: 0x000d, 0x3ff: 0x000d,
+	// Block 0x10, offset 0x400
+	0x400: 0x000d, 0x401: 0x000d, 0x402: 0x000d, 0x403: 0x000d, 0x404: 0x000d, 0x405: 0x000d,
+	0x406: 0x000d, 0x407: 0x000d, 0x408: 0x000d, 0x409: 0x000d, 0x40a: 0x000d, 0x40b: 0x000d,
+	0x40c: 0x000d, 0x40d: 0x000d, 0x40e: 0x000d, 0x40f: 0x000d, 0x410: 0x000d, 0x411: 0x000d,
+	0x412: 0x000d, 0x413: 0x000d, 0x414: 0x000d, 0x415: 0x000d, 0x416: 0x000d, 0x417: 0x000d,
+	0x418: 0x000d, 0x419: 0x000d, 0x41a: 0x000d, 0x41b: 0x000d, 0x41c: 0x000d, 0x41d: 0x000d,
+	0x41e: 0x000d, 0x41f: 0x000d, 0x420: 0x000d, 0x421: 0x000d, 0x422: 0x000d, 0x423: 0x000d,
+	0x424: 0x000d, 0x425: 0x000d, 0x426: 0x000d, 0x427: 0x000d, 0x428: 0x000d, 0x429: 0x000d,
+	0x42a: 0x000d, 0x42b: 0x000d, 0x42c: 0x000d, 0x42d: 0x000d, 0x42e: 0x000d, 0x42f: 0x000d,
+	0x430: 0x000d, 0x431: 0x000d, 0x432: 0x000d, 0x433: 0x000d, 0x434: 0x000d, 0x435: 0x000d,
+	0x436: 0x000d, 0x437: 0x000d, 0x438: 0x000d, 0x439: 0x000d, 0x43a: 0x000d, 0x43b: 0x000d,
+	0x43c: 0x000d, 0x43d: 0x000d, 0x43e: 0x000d, 0x43f: 0x000d,
+	// Block 0x11, offset 0x440
+	0x440: 0x000d, 0x441: 0x000d, 0x442: 0x000d, 0x443: 0x000d, 0x444: 0x000d, 0x445: 0x000d,
+	0x446: 0x000d, 0x447: 0x000d, 0x448: 0x000d, 0x449: 0x000d, 0x44a: 0x000d, 0x44b: 0x000d,
+	0x44c: 0x000d, 0x44d: 0x000d, 0x44e: 0x000d, 0x44f: 0x000d, 0x450: 0x000d, 0x451: 0x000d,
+	0x452: 0x000d, 0x453: 0x000d, 0x454: 0x000d, 0x455: 0x000d, 0x456: 0x000c, 0x457: 0x000c,
+	0x458: 0x000c, 0x459: 0x000c, 0x45a: 0x000c, 0x45b: 0x000c, 0x45c: 0x000c, 0x45d: 0x0005,
+	0x45e: 0x000a, 0x45f: 0x000c, 0x460: 0x000c, 0x461: 0x000c, 0x462: 0x000c, 0x463: 0x000c,
+	0x464: 0x000c, 0x465: 0x000d, 0x466: 0x000d, 0x467: 0x000c, 0x468: 0x000c, 0x469: 0x000a,
+	0x46a: 0x000c, 0x46b: 0x000c, 0x46c: 0x000c, 0x46d: 0x000c, 0x46e: 0x000d, 0x46f: 0x000d,
+	0x470: 0x0002, 0x471: 0x0002, 0x472: 0x0002, 0x473: 0x0002, 0x474: 0x0002, 0x475: 0x0002,
+	0x476: 0x0002, 0x477: 0x0002, 0x478: 0x0002, 0x479: 0x0002, 0x47a: 0x000d, 0x47b: 0x000d,
+	0x47c: 0x000d, 0x47d: 0x000d, 0x47e: 0x000d, 0x47f: 0x000d,
+	// Block 0x12, offset 0x480
+	0x480: 0x000d, 0x481: 0x000d, 0x482: 0x000d, 0x483: 0x000d, 0x484: 0x000d, 0x485: 0x000d,
+	0x486: 0x000d, 0x487: 0x000d, 0x488: 0x000d, 0x489: 0x000d, 0x48a: 0x000d, 0x48b: 0x000d,
+	0x48c: 0x000d, 0x48d: 0x000d, 0x48e: 0x000d, 0x48f: 0x000d, 0x490: 0x000d, 0x491: 0x000c,
+	0x492: 0x000d, 0x493: 0x000d, 0x494: 0x000d, 0x495: 0x000d, 0x496: 0x000d, 0x497: 0x000d,
+	0x498: 0x000d, 0x499: 0x000d, 0x49a: 0x000d, 0x49b: 0x000d, 0x49c: 0x000d, 0x49d: 0x000d,
+	0x49e: 0x000d, 0x49f: 0x000d, 0x4a0: 0x000d, 0x4a1: 0x000d, 0x4a2: 0x000d, 0x4a3: 0x000d,
+	0x4a4: 0x000d, 0x4a5: 0x000d, 0x4a6: 0x000d, 0x4a7: 0x000d, 0x4a8: 0x000d, 0x4a9: 0x000d,
+	0x4aa: 0x000d, 0x4ab: 0x000d, 0x4ac: 0x000d, 0x4ad: 0x000d, 0x4ae: 0x000d, 0x4af: 0x000d,
+	0x4b0: 0x000c, 0x4b1: 0x000c, 0x4b2: 0x000c, 0x4b3: 0x000c, 0x4b4: 0x000c, 0x4b5: 0x000c,
+	0x4b6: 0x000c, 0x4b7: 0x000c, 0x4b8: 0x000c, 0x4b9: 0x000c, 0x4ba: 0x000c, 0x4bb: 0x000c,
+	0x4bc: 0x000c, 0x4bd: 0x000c, 0x4be: 0x000c, 0x4bf: 0x000c,
+	// Block 0x13, offset 0x4c0
+	0x4c0: 0x000c, 0x4c1: 0x000c, 0x4c2: 0x000c, 0x4c3: 0x000c, 0x4c4: 0x000c, 0x4c5: 0x000c,
+	0x4c6: 0x000c, 0x4c7: 0x000c, 0x4c8: 0x000c, 0x4c9: 0x000c, 0x4ca: 0x000c, 0x4cb: 0x000d,
+	0x4cc: 0x000d, 0x4cd: 0x000d, 0x4ce: 0x000d, 0x4cf: 0x000d, 0x4d0: 0x000d, 0x4d1: 0x000d,
+	0x4d2: 0x000d, 0x4d3: 0x000d, 0x4d4: 0x000d, 0x4d5: 0x000d, 0x4d6: 0x000d, 0x4d7: 0x000d,
+	0x4d8: 0x000d, 0x4d9: 0x000d, 0x4da: 0x000d, 0x4db: 0x000d, 0x4dc: 0x000d, 0x4dd: 0x000d,
+	0x4de: 0x000d, 0x4df: 0x000d, 0x4e0: 0x000d, 0x4e1: 0x000d, 0x4e2: 0x000d, 0x4e3: 0x000d,
+	0x4e4: 0x000d, 0x4e5: 0x000d, 0x4e6: 0x000d, 0x4e7: 0x000d, 0x4e8: 0x000d, 0x4e9: 0x000d,
+	0x4ea: 0x000d, 0x4eb: 0x000d, 0x4ec: 0x000d, 0x4ed: 0x000d, 0x4ee: 0x000d, 0x4ef: 0x000d,
+	0x4f0: 0x000d, 0x4f1: 0x000d, 0x4f2: 0x000d, 0x4f3: 0x000d, 0x4f4: 0x000d, 0x4f5: 0x000d,
+	0x4f6: 0x000d, 0x4f7: 0x000d, 0x4f8: 0x000d, 0x4f9: 0x000d, 0x4fa: 0x000d, 0x4fb: 0x000d,
+	0x4fc: 0x000d, 0x4fd: 0x000d, 0x4fe: 0x000d, 0x4ff: 0x000d,
+	// Block 0x14, offset 0x500
+	0x500: 0x000d, 0x501: 0x000d, 0x502: 0x000d, 0x503: 0x000d, 0x504: 0x000d, 0x505: 0x000d,
+	0x506: 0x000d, 0x507: 0x000d, 0x508: 0x000d, 0x509: 0x000d, 0x50a: 0x000d, 0x50b: 0x000d,
+	0x50c: 0x000d, 0x50d: 0x000d, 0x50e: 0x000d, 0x50f: 0x000d, 0x510: 0x000d, 0x511: 0x000d,
+	0x512: 0x000d, 0x513: 0x000d, 0x514: 0x000d, 0x515: 0x000d, 0x516: 0x000d, 0x517: 0x000d,
+	0x518: 0x000d, 0x519: 0x000d, 0x51a: 0x000d, 0x51b: 0x000d, 0x51c: 0x000d, 0x51d: 0x000d,
+	0x51e: 0x000d, 0x51f: 0x000d, 0x520: 0x000d, 0x521: 0x000d, 0x522: 0x000d, 0x523: 0x000d,
+	0x524: 0x000d, 0x525: 0x000d, 0x526: 0x000c, 0x527: 0x000c, 0x528: 0x000c, 0x529: 0x000c,
+	0x52a: 0x000c, 0x52b: 0x000c, 0x52c: 0x000c, 0x52d: 0x000c, 0x52e: 0x000c, 0x52f: 0x000c,
+	0x530: 0x000c, 0x531: 0x000d, 0x532: 0x000d, 0x533: 0x000d, 0x534: 0x000d, 0x535: 0x000d,
+	0x536: 0x000d, 0x537: 0x000d, 0x538: 0x000d, 0x539: 0x000d, 0x53a: 0x000d, 0x53b: 0x000d,
+	0x53c: 0x000d, 0x53d: 0x000d, 0x53e: 0x000d, 0x53f: 0x000d,
+	// Block 0x15, offset 0x540
+	0x540: 0x0001, 0x541: 0x0001, 0x542: 0x0001, 0x543: 0x0001, 0x544: 0x0001, 0x545: 0x0001,
+	0x546: 0x0001, 0x547: 0x0001, 0x548: 0x0001, 0x549: 0x0001, 0x54a: 0x0001, 0x54b: 0x0001,
+	0x54c: 0x0001, 0x54d: 0x0001, 0x54e: 0x0001, 0x54f: 0x0001, 0x550: 0x0001, 0x551: 0x0001,
+	0x552: 0x0001, 0x553: 0x0001, 0x554: 0x0001, 0x555: 0x0001, 0x556: 0x0001, 0x557: 0x0001,
+	0x558: 0x0001, 0x559: 0x0001, 0x55a: 0x0001, 0x55b: 0x0001, 0x55c: 0x0001, 0x55d: 0x0001,
+	0x55e: 0x0001, 0x55f: 0x0001, 0x560: 0x0001, 0x561: 0x0001, 0x562: 0x0001, 0x563: 0x0001,
+	0x564: 0x0001, 0x565: 0x0001, 0x566: 0x0001, 0x567: 0x0001, 0x568: 0x0001, 0x569: 0x0001,
+	0x56a: 0x0001, 0x56b: 0x000c, 0x56c: 0x000c, 0x56d: 0x000c, 0x56e: 0x000c, 0x56f: 0x000c,
+	0x570: 0x000c, 0x571: 0x000c, 0x572: 0x000c, 0x573: 0x000c, 0x574: 0x0001, 0x575: 0x0001,
+	0x576: 0x000a, 0x577: 0x000a, 0x578: 0x000a, 0x579: 0x000a, 0x57a: 0x0001, 0x57b: 0x0001,
+	0x57c: 0x0001, 0x57d: 0x0001, 0x57e: 0x0001, 0x57f: 0x0001,
+	// Block 0x16, offset 0x580
+	0x580: 0x0001, 0x581: 0x0001, 0x582: 0x0001, 0x583: 0x0001, 0x584: 0x0001, 0x585: 0x0001,
+	0x586: 0x0001, 0x587: 0x0001, 0x588: 0x0001, 0x589: 0x0001, 0x58a: 0x0001, 0x58b: 0x0001,
+	0x58c: 0x0001, 0x58d: 0x0001, 0x58e: 0x0001, 0x58f: 0x0001, 0x590: 0x0001, 0x591: 0x0001,
+	0x592: 0x0001, 0x593: 0x0001, 0x594: 0x0001, 0x595: 0x0001, 0x596: 0x000c, 0x597: 0x000c,
+	0x598: 0x000c, 0x599: 0x000c, 0x59a: 0x0001, 0x59b: 0x000c, 0x59c: 0x000c, 0x59d: 0x000c,
+	0x59e: 0x000c, 0x59f: 0x000c, 0x5a0: 0x000c, 0x5a1: 0x000c, 0x5a2: 0x000c, 0x5a3: 0x000c,
+	0x5a4: 0x0001, 0x5a5: 0x000c, 0x5a6: 0x000c, 0x5a7: 0x000c, 0x5a8: 0x0001, 0x5a9: 0x000c,
+	0x5aa: 0x000c, 0x5ab: 0x000c, 0x5ac: 0x000c, 0x5ad: 0x000c, 0x5ae: 0x0001, 0x5af: 0x0001,
+	0x5b0: 0x0001, 0x5b1: 0x0001, 0x5b2: 0x0001, 0x5b3: 0x0001, 0x5b4: 0x0001, 0x5b5: 0x0001,
+	0x5b6: 0x0001, 0x5b7: 0x0001, 0x5b8: 0x0001, 0x5b9: 0x0001, 0x5ba: 0x0001, 0x5bb: 0x0001,
+	0x5bc: 0x0001, 0x5bd: 0x0001, 0x5be: 0x0001, 0x5bf: 0x0001,
+	// Block 0x17, offset 0x5c0
+	0x5c0: 0x0001, 0x5c1: 0x0001, 0x5c2: 0x0001, 0x5c3: 0x0001, 0x5c4: 0x0001, 0x5c5: 0x0001,
+	0x5c6: 0x0001, 0x5c7: 0x0001, 0x5c8: 0x0001, 0x5c9: 0x0001, 0x5ca: 0x0001, 0x5cb: 0x0001,
+	0x5cc: 0x0001, 0x5cd: 0x0001, 0x5ce: 0x0001, 0x5cf: 0x0001, 0x5d0: 0x0001, 0x5d1: 0x0001,
+	0x5d2: 0x0001, 0x5d3: 0x0001, 0x5d4: 0x0001, 0x5d5: 0x0001, 0x5d6: 0x0001, 0x5d7: 0x0001,
+	0x5d8: 0x0001, 0x5d9: 0x000c, 0x5da: 0x000c, 0x5db: 0x000c, 0x5dc: 0x0001, 0x5dd: 0x0001,
+	0x5de: 0x0001, 0x5df: 0x0001, 0x5e0: 0x0001, 0x5e1: 0x0001, 0x5e2: 0x0001, 0x5e3: 0x0001,
+	0x5e4: 0x0001, 0x5e5: 0x0001, 0x5e6: 0x0001, 0x5e7: 0x0001, 0x5e8: 0x0001, 0x5e9: 0x0001,
+	0x5ea: 0x0001, 0x5eb: 0x0001, 0x5ec: 0x0001, 0x5ed: 0x0001, 0x5ee: 0x0001, 0x5ef: 0x0001,
+	0x5f0: 0x0001, 0x5f1: 0x0001, 0x5f2: 0x0001, 0x5f3: 0x0001, 0x5f4: 0x0001, 0x5f5: 0x0001,
+	0x5f6: 0x0001, 0x5f7: 0x0001, 0x5f8: 0x0001, 0x5f9: 0x0001, 0x5fa: 0x0001, 0x5fb: 0x0001,
+	0x5fc: 0x0001, 0x5fd: 0x0001, 0x5fe: 0x0001, 0x5ff: 0x0001,
+	// Block 0x18, offset 0x600
+	0x600: 0x0001, 0x601: 0x0001, 0x602: 0x0001, 0x603: 0x0001, 0x604: 0x0001, 0x605: 0x0001,
+	0x606: 0x0001, 0x607: 0x0001, 0x608: 0x0001, 0x609: 0x0001, 0x60a: 0x0001, 0x60b: 0x0001,
+	0x60c: 0x0001, 0x60d: 0x0001, 0x60e: 0x0001, 0x60f: 0x0001, 0x610: 0x0001, 0x611: 0x0001,
+	0x612: 0x0001, 0x613: 0x0001, 0x614: 0x0001, 0x615: 0x0001, 0x616: 0x0001, 0x617: 0x0001,
+	0x618: 0x0001, 0x619: 0x0001, 0x61a: 0x0001, 0x61b: 0x0001, 0x61c: 0x0001, 0x61d: 0x0001,
+	0x61e: 0x0001, 0x61f: 0x0001, 0x620: 0x000d, 0x621: 0x000d, 0x622: 0x000d, 0x623: 0x000d,
+	0x624: 0x000d, 0x625: 0x000d, 0x626: 0x000d, 0x627: 0x000d, 0x628: 0x000d, 0x629: 0x000d,
+	0x62a: 0x000d, 0x62b: 0x000d, 0x62c: 0x000d, 0x62d: 0x000d, 0x62e: 0x000d, 0x62f: 0x000d,
+	0x630: 0x000d, 0x631: 0x000d, 0x632: 0x000d, 0x633: 0x000d, 0x634: 0x000d, 0x635: 0x000d,
+	0x636: 0x000d, 0x637: 0x000d, 0x638: 0x000d, 0x639: 0x000d, 0x63a: 0x000d, 0x63b: 0x000d,
+	0x63c: 0x000d, 0x63d: 0x000d, 0x63e: 0x000d, 0x63f: 0x000d,
+	// Block 0x19, offset 0x640
+	0x640: 0x000d, 0x641: 0x000d, 0x642: 0x000d, 0x643: 0x000d, 0x644: 0x000d, 0x645: 0x000d,
+	0x646: 0x000d, 0x647: 0x000d, 0x648: 0x000d, 0x649: 0x000d, 0x64a: 0x000d, 0x64b: 0x000d,
+	0x64c: 0x000d, 0x64d: 0x000d, 0x64e: 0x000d, 0x64f: 0x000d, 0x650: 0x000d, 0x651: 0x000d,
+	0x652: 0x000d, 0x653: 0x000d, 0x654: 0x000c, 0x655: 0x000c, 0x656: 0x000c, 0x657: 0x000c,
+	0x658: 0x000c, 0x659: 0x000c, 0x65a: 0x000c, 0x65b: 0x000c, 0x65c: 0x000c, 0x65d: 0x000c,
+	0x65e: 0x000c, 0x65f: 0x000c, 0x660: 0x000c, 0x661: 0x000c, 0x662: 0x0005, 0x663: 0x000c,
+	0x664: 0x000c, 0x665: 0x000c, 0x666: 0x000c, 0x667: 0x000c, 0x668: 0x000c, 0x669: 0x000c,
+	0x66a: 0x000c, 0x66b: 0x000c, 0x66c: 0x000c, 0x66d: 0x000c, 0x66e: 0x000c, 0x66f: 0x000c,
+	0x670: 0x000c, 0x671: 0x000c, 0x672: 0x000c, 0x673: 0x000c, 0x674: 0x000c, 0x675: 0x000c,
+	0x676: 0x000c, 0x677: 0x000c, 0x678: 0x000c, 0x679: 0x000c, 0x67a: 0x000c, 0x67b: 0x000c,
+	0x67c: 0x000c, 0x67d: 0x000c, 0x67e: 0x000c, 0x67f: 0x000c,
+	// Block 0x1a, offset 0x680
+	0x680: 0x000c, 0x681: 0x000c, 0x682: 0x000c,
+	0x6ba: 0x000c,
+	0x6bc: 0x000c,
+	// Block 0x1b, offset 0x6c0
+	0x6c1: 0x000c, 0x6c2: 0x000c, 0x6c3: 0x000c, 0x6c4: 0x000c, 0x6c5: 0x000c,
+	0x6c6: 0x000c, 0x6c7: 0x000c, 0x6c8: 0x000c,
+	0x6cd: 0x000c, 0x6d1: 0x000c,
+	0x6d2: 0x000c, 0x6d3: 0x000c, 0x6d4: 0x000c, 0x6d5: 0x000c, 0x6d6: 0x000c, 0x6d7: 0x000c,
+	0x6e2: 0x000c, 0x6e3: 0x000c,
+	// Block 0x1c, offset 0x700
+	0x701: 0x000c,
+	0x73c: 0x000c,
+	// Block 0x1d, offset 0x740
+	0x741: 0x000c, 0x742: 0x000c, 0x743: 0x000c, 0x744: 0x000c,
+	0x74d: 0x000c,
+	0x762: 0x000c, 0x763: 0x000c,
+	0x772: 0x0004, 0x773: 0x0004,
+	0x77b: 0x0004,
+	// Block 0x1e, offset 0x780
+	0x781: 0x000c, 0x782: 0x000c,
+	0x7bc: 0x000c,
+	// Block 0x1f, offset 0x7c0
+	0x7c1: 0x000c, 0x7c2: 0x000c,
+	0x7c7: 0x000c, 0x7c8: 0x000c, 0x7cb: 0x000c,
+	0x7cc: 0x000c, 0x7cd: 0x000c, 0x7d1: 0x000c,
+	0x7f0: 0x000c, 0x7f1: 0x000c, 0x7f5: 0x000c,
+	// Block 0x20, offset 0x800
+	0x801: 0x000c, 0x802: 0x000c, 0x803: 0x000c, 0x804: 0x000c, 0x805: 0x000c,
+	0x807: 0x000c, 0x808: 0x000c,
+	0x80d: 0x000c,
+	0x822: 0x000c, 0x823: 0x000c,
+	0x831: 0x0004,
+	// Block 0x21, offset 0x840
+	0x841: 0x000c,
+	0x87c: 0x000c, 0x87f: 0x000c,
+	// Block 0x22, offset 0x880
+	0x881: 0x000c, 0x882: 0x000c, 0x883: 0x000c, 0x884: 0x000c,
+	0x88d: 0x000c,
+	0x896: 0x000c,
+	0x8a2: 0x000c, 0x8a3: 0x000c,
+	// Block 0x23, offset 0x8c0
+	0x8c2: 0x000c,
+	// Block 0x24, offset 0x900
+	0x900: 0x000c,
+	0x90d: 0x000c,
+	0x933: 0x000a, 0x934: 0x000a, 0x935: 0x000a,
+	0x936: 0x000a, 0x937: 0x000a, 0x938: 0x000a, 0x939: 0x0004, 0x93a: 0x000a,
+	// Block 0x25, offset 0x940
+	0x940: 0x000c,
+	0x97e: 0x000c, 0x97f: 0x000c,
+	// Block 0x26, offset 0x980
+	0x980: 0x000c,
+	0x986: 0x000c, 0x987: 0x000c, 0x988: 0x000c, 0x98a: 0x000c, 0x98b: 0x000c,
+	0x98c: 0x000c, 0x98d: 0x000c,
+	0x995: 0x000c, 0x996: 0x000c,
+	0x9a2: 0x000c, 0x9a3: 0x000c,
+	0x9b8: 0x000a, 0x9b9: 0x000a, 0x9ba: 0x000a, 0x9bb: 0x000a,
+	0x9bc: 0x000a, 0x9bd: 0x000a, 0x9be: 0x000a,
+	// Block 0x27, offset 0x9c0
+	0x9cc: 0x000c, 0x9cd: 0x000c,
+	0x9e2: 0x000c, 0x9e3: 0x000c,
+	// Block 0x28, offset 0xa00
+	0xa01: 0x000c,
+	// Block 0x29, offset 0xa40
+	0xa41: 0x000c, 0xa42: 0x000c, 0xa43: 0x000c, 0xa44: 0x000c,
+	0xa4d: 0x000c,
+	0xa62: 0x000c, 0xa63: 0x000c,
+	// Block 0x2a, offset 0xa80
+	0xa8a: 0x000c,
+	0xa92: 0x000c, 0xa93: 0x000c, 0xa94: 0x000c, 0xa96: 0x000c,
+	// Block 0x2b, offset 0xac0
+	0xaf1: 0x000c, 0xaf4: 0x000c, 0xaf5: 0x000c,
+	0xaf6: 0x000c, 0xaf7: 0x000c, 0xaf8: 0x000c, 0xaf9: 0x000c, 0xafa: 0x000c,
+	0xaff: 0x0004,
+	// Block 0x2c, offset 0xb00
+	0xb07: 0x000c, 0xb08: 0x000c, 0xb09: 0x000c, 0xb0a: 0x000c, 0xb0b: 0x000c,
+	0xb0c: 0x000c, 0xb0d: 0x000c, 0xb0e: 0x000c,
+	// Block 0x2d, offset 0xb40
+	0xb71: 0x000c, 0xb74: 0x000c, 0xb75: 0x000c,
+	0xb76: 0x000c, 0xb77: 0x000c, 0xb78: 0x000c, 0xb79: 0x000c, 0xb7b: 0x000c,
+	0xb7c: 0x000c,
+	// Block 0x2e, offset 0xb80
+	0xb88: 0x000c, 0xb89: 0x000c, 0xb8a: 0x000c, 0xb8b: 0x000c,
+	0xb8c: 0x000c, 0xb8d: 0x000c,
+	// Block 0x2f, offset 0xbc0
+	0xbd8: 0x000c, 0xbd9: 0x000c,
+	0xbf5: 0x000c,
+	0xbf7: 0x000c, 0xbf9: 0x000c, 0xbfa: 0x003a, 0xbfb: 0x002a,
+	0xbfc: 0x003a, 0xbfd: 0x002a,
+	// Block 0x30, offset 0xc00
+	0xc31: 0x000c, 0xc32: 0x000c, 0xc33: 0x000c, 0xc34: 0x000c, 0xc35: 0x000c,
+	0xc36: 0x000c, 0xc37: 0x000c, 0xc38: 0x000c, 0xc39: 0x000c, 0xc3a: 0x000c, 0xc3b: 0x000c,
+	0xc3c: 0x000c, 0xc3d: 0x000c, 0xc3e: 0x000c,
+	// Block 0x31, offset 0xc40
+	0xc40: 0x000c, 0xc41: 0x000c, 0xc42: 0x000c, 0xc43: 0x000c, 0xc44: 0x000c,
+	0xc46: 0x000c, 0xc47: 0x000c,
+	0xc4d: 0x000c, 0xc4e: 0x000c, 0xc4f: 0x000c, 0xc50: 0x000c, 0xc51: 0x000c,
+	0xc52: 0x000c, 0xc53: 0x000c, 0xc54: 0x000c, 0xc55: 0x000c, 0xc56: 0x000c, 0xc57: 0x000c,
+	0xc59: 0x000c, 0xc5a: 0x000c, 0xc5b: 0x000c, 0xc5c: 0x000c, 0xc5d: 0x000c,
+	0xc5e: 0x000c, 0xc5f: 0x000c, 0xc60: 0x000c, 0xc61: 0x000c, 0xc62: 0x000c, 0xc63: 0x000c,
+	0xc64: 0x000c, 0xc65: 0x000c, 0xc66: 0x000c, 0xc67: 0x000c, 0xc68: 0x000c, 0xc69: 0x000c,
+	0xc6a: 0x000c, 0xc6b: 0x000c, 0xc6c: 0x000c, 0xc6d: 0x000c, 0xc6e: 0x000c, 0xc6f: 0x000c,
+	0xc70: 0x000c, 0xc71: 0x000c, 0xc72: 0x000c, 0xc73: 0x000c, 0xc74: 0x000c, 0xc75: 0x000c,
+	0xc76: 0x000c, 0xc77: 0x000c, 0xc78: 0x000c, 0xc79: 0x000c, 0xc7a: 0x000c, 0xc7b: 0x000c,
+	0xc7c: 0x000c,
+	// Block 0x32, offset 0xc80
+	0xc86: 0x000c,
+	// Block 0x33, offset 0xcc0
+	0xced: 0x000c, 0xcee: 0x000c, 0xcef: 0x000c,
+	0xcf0: 0x000c, 0xcf2: 0x000c, 0xcf3: 0x000c, 0xcf4: 0x000c, 0xcf5: 0x000c,
+	0xcf6: 0x000c, 0xcf7: 0x000c, 0xcf9: 0x000c, 0xcfa: 0x000c,
+	0xcfd: 0x000c, 0xcfe: 0x000c,
+	// Block 0x34, offset 0xd00
+	0xd18: 0x000c, 0xd19: 0x000c,
+	0xd1e: 0x000c, 0xd1f: 0x000c, 0xd20: 0x000c,
+	0xd31: 0x000c, 0xd32: 0x000c, 0xd33: 0x000c, 0xd34: 0x000c,
+	// Block 0x35, offset 0xd40
+	0xd42: 0x000c, 0xd45: 0x000c,
+	0xd46: 0x000c,
+	0xd4d: 0x000c,
+	0xd5d: 0x000c,
+	// Block 0x36, offset 0xd80
+	0xd9d: 0x000c,
+	0xd9e: 0x000c, 0xd9f: 0x000c,
+	// Block 0x37, offset 0xdc0
+	0xdd0: 0x000a, 0xdd1: 0x000a,
+	0xdd2: 0x000a, 0xdd3: 0x000a, 0xdd4: 0x000a, 0xdd5: 0x000a, 0xdd6: 0x000a, 0xdd7: 0x000a,
+	0xdd8: 0x000a, 0xdd9: 0x000a,
+	// Block 0x38, offset 0xe00
+	0xe00: 0x000a,
+	// Block 0x39, offset 0xe40
+	0xe40: 0x0009,
+	0xe5b: 0x007a, 0xe5c: 0x006a,
+	// Block 0x3a, offset 0xe80
+	0xe92: 0x000c, 0xe93: 0x000c, 0xe94: 0x000c,
+	0xeb2: 0x000c, 0xeb3: 0x000c, 0xeb4: 0x000c,
+	// Block 0x3b, offset 0xec0
+	0xed2: 0x000c, 0xed3: 0x000c,
+	0xef2: 0x000c, 0xef3: 0x000c,
+	// Block 0x3c, offset 0xf00
+	0xf34: 0x000c, 0xf35: 0x000c,
+	0xf37: 0x000c, 0xf38: 0x000c, 0xf39: 0x000c, 0xf3a: 0x000c, 0xf3b: 0x000c,
+	0xf3c: 0x000c, 0xf3d: 0x000c,
+	// Block 0x3d, offset 0xf40
+	0xf46: 0x000c, 0xf49: 0x000c, 0xf4a: 0x000c, 0xf4b: 0x000c,
+	0xf4c: 0x000c, 0xf4d: 0x000c, 0xf4e: 0x000c, 0xf4f: 0x000c, 0xf50: 0x000c, 0xf51: 0x000c,
+	0xf52: 0x000c, 0xf53: 0x000c,
+	0xf5b: 0x0004, 0xf5d: 0x000c,
+	0xf70: 0x000a, 0xf71: 0x000a, 0xf72: 0x000a, 0xf73: 0x000a, 0xf74: 0x000a, 0xf75: 0x000a,
+	0xf76: 0x000a, 0xf77: 0x000a, 0xf78: 0x000a, 0xf79: 0x000a,
+	// Block 0x3e, offset 0xf80
+	0xf80: 0x000a, 0xf81: 0x000a, 0xf82: 0x000a, 0xf83: 0x000a, 0xf84: 0x000a, 0xf85: 0x000a,
+	0xf86: 0x000a, 0xf87: 0x000a, 0xf88: 0x000a, 0xf89: 0x000a, 0xf8a: 0x000a, 0xf8b: 0x000c,
+	0xf8c: 0x000c, 0xf8d: 0x000c, 0xf8e: 0x000b,
+	// Block 0x3f, offset 0xfc0
+	0xfc5: 0x000c,
+	0xfc6: 0x000c,
+	0xfe9: 0x000c,
+	// Block 0x40, offset 0x1000
+	0x1020: 0x000c, 0x1021: 0x000c, 0x1022: 0x000c,
+	0x1027: 0x000c, 0x1028: 0x000c,
+	0x1032: 0x000c,
+	0x1039: 0x000c, 0x103a: 0x000c, 0x103b: 0x000c,
+	// Block 0x41, offset 0x1040
+	0x1040: 0x000a, 0x1044: 0x000a, 0x1045: 0x000a,
+	// Block 0x42, offset 0x1080
+	0x109e: 0x000a, 0x109f: 0x000a, 0x10a0: 0x000a, 0x10a1: 0x000a, 0x10a2: 0x000a, 0x10a3: 0x000a,
+	0x10a4: 0x000a, 0x10a5: 0x000a, 0x10a6: 0x000a, 0x10a7: 0x000a, 0x10a8: 0x000a, 0x10a9: 0x000a,
+	0x10aa: 0x000a, 0x10ab: 0x000a, 0x10ac: 0x000a, 0x10ad: 0x000a, 0x10ae: 0x000a, 0x10af: 0x000a,
+	0x10b0: 0x000a, 0x10b1: 0x000a, 0x10b2: 0x000a, 0x10b3: 0x000a, 0x10b4: 0x000a, 0x10b5: 0x000a,
+	0x10b6: 0x000a, 0x10b7: 0x000a, 0x10b8: 0x000a, 0x10b9: 0x000a, 0x10ba: 0x000a, 0x10bb: 0x000a,
+	0x10bc: 0x000a, 0x10bd: 0x000a, 0x10be: 0x000a, 0x10bf: 0x000a,
+	// Block 0x43, offset 0x10c0
+	0x10d7: 0x000c,
+	0x10d8: 0x000c, 0x10db: 0x000c,
+	// Block 0x44, offset 0x1100
+	0x1116: 0x000c,
+	0x1118: 0x000c, 0x1119: 0x000c, 0x111a: 0x000c, 0x111b: 0x000c, 0x111c: 0x000c, 0x111d: 0x000c,
+	0x111e: 0x000c, 0x1120: 0x000c, 0x1122: 0x000c,
+	0x1125: 0x000c, 0x1126: 0x000c, 0x1127: 0x000c, 0x1128: 0x000c, 0x1129: 0x000c,
+	0x112a: 0x000c, 0x112b: 0x000c, 0x112c: 0x000c,
+	0x1133: 0x000c, 0x1134: 0x000c, 0x1135: 0x000c,
+	0x1136: 0x000c, 0x1137: 0x000c, 0x1138: 0x000c, 0x1139: 0x000c, 0x113a: 0x000c, 0x113b: 0x000c,
+	0x113c: 0x000c, 0x113f: 0x000c,
+	// Block 0x45, offset 0x1140
+	0x1170: 0x000c, 0x1171: 0x000c, 0x1172: 0x000c, 0x1173: 0x000c, 0x1174: 0x000c, 0x1175: 0x000c,
+	0x1176: 0x000c, 0x1177: 0x000c, 0x1178: 0x000c, 0x1179: 0x000c, 0x117a: 0x000c, 0x117b: 0x000c,
+	0x117c: 0x000c, 0x117d: 0x000c, 0x117e: 0x000c,
+	// Block 0x46, offset 0x1180
+	0x1180: 0x000c, 0x1181: 0x000c, 0x1182: 0x000c, 0x1183: 0x000c,
+	0x11b4: 0x000c,
+	0x11b6: 0x000c, 0x11b7: 0x000c, 0x11b8: 0x000c, 0x11b9: 0x000c, 0x11ba: 0x000c,
+	0x11bc: 0x000c,
+	// Block 0x47, offset 0x11c0
+	0x11c2: 0x000c,
+	0x11eb: 0x000c, 0x11ec: 0x000c, 0x11ed: 0x000c, 0x11ee: 0x000c, 0x11ef: 0x000c,
+	0x11f0: 0x000c, 0x11f1: 0x000c, 0x11f2: 0x000c, 0x11f3: 0x000c,
+	// Block 0x48, offset 0x1200
+	0x1200: 0x000c, 0x1201: 0x000c,
+	0x1222: 0x000c, 0x1223: 0x000c,
+	0x1224: 0x000c, 0x1225: 0x000c, 0x1228: 0x000c, 0x1229: 0x000c,
+	0x122b: 0x000c, 0x122c: 0x000c, 0x122d: 0x000c,
+	// Block 0x49, offset 0x1240
+	0x1266: 0x000c, 0x1268: 0x000c, 0x1269: 0x000c,
+	0x126d: 0x000c, 0x126f: 0x000c,
+	0x1270: 0x000c, 0x1271: 0x000c,
+	// Block 0x4a, offset 0x1280
+	0x12ac: 0x000c, 0x12ad: 0x000c, 0x12ae: 0x000c, 0x12af: 0x000c,
+	0x12b0: 0x000c, 0x12b1: 0x000c, 0x12b2: 0x000c, 0x12b3: 0x000c,
+	0x12b6: 0x000c, 0x12b7: 0x000c,
+	// Block 0x4b, offset 0x12c0
+	0x12d0: 0x000c, 0x12d1: 0x000c,
+	0x12d2: 0x000c, 0x12d4: 0x000c, 0x12d5: 0x000c, 0x12d6: 0x000c, 0x12d7: 0x000c,
+	0x12d8: 0x000c, 0x12d9: 0x000c, 0x12da: 0x000c, 0x12db: 0x000c, 0x12dc: 0x000c, 0x12dd: 0x000c,
+	0x12de: 0x000c, 0x12df: 0x000c, 0x12e0: 0x000c, 0x12e2: 0x000c, 0x12e3: 0x000c,
+	0x12e4: 0x000c, 0x12e5: 0x000c, 0x12e6: 0x000c, 0x12e7: 0x000c, 0x12e8: 0x000c,
+	0x12ed: 0x000c,
+	0x12f4: 0x000c,
+	0x12f8: 0x000c, 0x12f9: 0x000c,
+	// Block 0x4c, offset 0x1300
+	0x1300: 0x000c, 0x1301: 0x000c, 0x1302: 0x000c, 0x1303: 0x000c, 0x1304: 0x000c, 0x1305: 0x000c,
+	0x1306: 0x000c, 0x1307: 0x000c, 0x1308: 0x000c, 0x1309: 0x000c, 0x130a: 0x000c, 0x130b: 0x000c,
+	0x130c: 0x000c, 0x130d: 0x000c, 0x130e: 0x000c, 0x130f: 0x000c, 0x1310: 0x000c, 0x1311: 0x000c,
+	0x1312: 0x000c, 0x1313: 0x000c, 0x1314: 0x000c, 0x1315: 0x000c, 0x1316: 0x000c, 0x1317: 0x000c,
+	0x1318: 0x000c, 0x1319: 0x000c, 0x131a: 0x000c, 0x131b: 0x000c, 0x131c: 0x000c, 0x131d: 0x000c,
+	0x131e: 0x000c, 0x131f: 0x000c, 0x1320: 0x000c, 0x1321: 0x000c, 0x1322: 0x000c, 0x1323: 0x000c,
+	0x1324: 0x000c, 0x1325: 0x000c, 0x1326: 0x000c, 0x1327: 0x000c, 0x1328: 0x000c, 0x1329: 0x000c,
+	0x132a: 0x000c, 0x132b: 0x000c, 0x132c: 0x000c, 0x132d: 0x000c, 0x132e: 0x000c, 0x132f: 0x000c,
+	0x1330: 0x000c, 0x1331: 0x000c, 0x1332: 0x000c, 0x1333: 0x000c, 0x1334: 0x000c, 0x1335: 0x000c,
+	0x133b: 0x000c,
+	0x133c: 0x000c, 0x133d: 0x000c, 0x133e: 0x000c, 0x133f: 0x000c,
+	// Block 0x4d, offset 0x1340
+	0x137d: 0x000a, 0x137f: 0x000a,
+	// Block 0x4e, offset 0x1380
+	0x1380: 0x000a, 0x1381: 0x000a,
+	0x138d: 0x000a, 0x138e: 0x000a, 0x138f: 0x000a,
+	0x139d: 0x000a,
+	0x139e: 0x000a, 0x139f: 0x000a,
+	0x13ad: 0x000a, 0x13ae: 0x000a, 0x13af: 0x000a,
+	0x13bd: 0x000a, 0x13be: 0x000a,
+	// Block 0x4f, offset 0x13c0
+	0x13c0: 0x0009, 0x13c1: 0x0009, 0x13c2: 0x0009, 0x13c3: 0x0009, 0x13c4: 0x0009, 0x13c5: 0x0009,
+	0x13c6: 0x0009, 0x13c7: 0x0009, 0x13c8: 0x0009, 0x13c9: 0x0009, 0x13ca: 0x0009, 0x13cb: 0x000b,
+	0x13cc: 0x000b, 0x13cd: 0x000b, 0x13cf: 0x0001, 0x13d0: 0x000a, 0x13d1: 0x000a,
+	0x13d2: 0x000a, 0x13d3: 0x000a, 0x13d4: 0x000a, 0x13d5: 0x000a, 0x13d6: 0x000a, 0x13d7: 0x000a,
+	0x13d8: 0x000a, 0x13d9: 0x000a, 0x13da: 0x000a, 0x13db: 0x000a, 0x13dc: 0x000a, 0x13dd: 0x000a,
+	0x13de: 0x000a, 0x13df: 0x000a, 0x13e0: 0x000a, 0x13e1: 0x000a, 0x13e2: 0x000a, 0x13e3: 0x000a,
+	0x13e4: 0x000a, 0x13e5: 0x000a, 0x13e6: 0x000a, 0x13e7: 0x000a, 0x13e8: 0x0009, 0x13e9: 0x0007,
+	0x13ea: 0x000e, 0x13eb: 0x000e, 0x13ec: 0x000e, 0x13ed: 0x000e, 0x13ee: 0x000e, 0x13ef: 0x0006,
+	0x13f0: 0x0004, 0x13f1: 0x0004, 0x13f2: 0x0004, 0x13f3: 0x0004, 0x13f4: 0x0004, 0x13f5: 0x000a,
+	0x13f6: 0x000a, 0x13f7: 0x000a, 0x13f8: 0x000a, 0x13f9: 0x000a, 0x13fa: 0x000a, 0x13fb: 0x000a,
+	0x13fc: 0x000a, 0x13fd: 0x000a, 0x13fe: 0x000a, 0x13ff: 0x000a,
+	// Block 0x50, offset 0x1400
+	0x1400: 0x000a, 0x1401: 0x000a, 0x1402: 0x000a, 0x1403: 0x000a, 0x1404: 0x0006, 0x1405: 0x009a,
+	0x1406: 0x008a, 0x1407: 0x000a, 0x1408: 0x000a, 0x1409: 0x000a, 0x140a: 0x000a, 0x140b: 0x000a,
+	0x140c: 0x000a, 0x140d: 0x000a, 0x140e: 0x000a, 0x140f: 0x000a, 0x1410: 0x000a, 0x1411: 0x000a,
+	0x1412: 0x000a, 0x1413: 0x000a, 0x1414: 0x000a, 0x1415: 0x000a, 0x1416: 0x000a, 0x1417: 0x000a,
+	0x1418: 0x000a, 0x1419: 0x000a, 0x141a: 0x000a, 0x141b: 0x000a, 0x141c: 0x000a, 0x141d: 0x000a,
+	0x141e: 0x000a, 0x141f: 0x0009, 0x1420: 0x000b, 0x1421: 0x000b, 0x1422: 0x000b, 0x1423: 0x000b,
+	0x1424: 0x000b, 0x1425: 0x000b, 0x1426: 0x000e, 0x1427: 0x000e, 0x1428: 0x000e, 0x1429: 0x000e,
+	0x142a: 0x000b, 0x142b: 0x000b, 0x142c: 0x000b, 0x142d: 0x000b, 0x142e: 0x000b, 0x142f: 0x000b,
+	0x1430: 0x0002, 0x1434: 0x0002, 0x1435: 0x0002,
+	0x1436: 0x0002, 0x1437: 0x0002, 0x1438: 0x0002, 0x1439: 0x0002, 0x143a: 0x0003, 0x143b: 0x0003,
+	0x143c: 0x000a, 0x143d: 0x009a, 0x143e: 0x008a,
+	// Block 0x51, offset 0x1440
+	0x1440: 0x0002, 0x1441: 0x0002, 0x1442: 0x0002, 0x1443: 0x0002, 0x1444: 0x0002, 0x1445: 0x0002,
+	0x1446: 0x0002, 0x1447: 0x0002, 0x1448: 0x0002, 0x1449: 0x0002, 0x144a: 0x0003, 0x144b: 0x0003,
+	0x144c: 0x000a, 0x144d: 0x009a, 0x144e: 0x008a,
+	0x1460: 0x0004, 0x1461: 0x0004, 0x1462: 0x0004, 0x1463: 0x0004,
+	0x1464: 0x0004, 0x1465: 0x0004, 0x1466: 0x0004, 0x1467: 0x0004, 0x1468: 0x0004, 0x1469: 0x0004,
+	0x146a: 0x0004, 0x146b: 0x0004, 0x146c: 0x0004, 0x146d: 0x0004, 0x146e: 0x0004, 0x146f: 0x0004,
+	0x1470: 0x0004, 0x1471: 0x0004, 0x1472: 0x0004, 0x1473: 0x0004, 0x1474: 0x0004, 0x1475: 0x0004,
+	0x1476: 0x0004, 0x1477: 0x0004, 0x1478: 0x0004, 0x1479: 0x0004, 0x147a: 0x0004, 0x147b: 0x0004,
+	0x147c: 0x0004, 0x147d: 0x0004, 0x147e: 0x0004, 0x147f: 0x0004,
+	// Block 0x52, offset 0x1480
+	0x1480: 0x0004, 0x1481: 0x0004, 0x1482: 0x0004, 0x1483: 0x0004, 0x1484: 0x0004, 0x1485: 0x0004,
+	0x1486: 0x0004, 0x1487: 0x0004, 0x1488: 0x0004, 0x1489: 0x0004, 0x148a: 0x0004, 0x148b: 0x0004,
+	0x148c: 0x0004, 0x148d: 0x0004, 0x148e: 0x0004, 0x148f: 0x0004, 0x1490: 0x000c, 0x1491: 0x000c,
+	0x1492: 0x000c, 0x1493: 0x000c, 0x1494: 0x000c, 0x1495: 0x000c, 0x1496: 0x000c, 0x1497: 0x000c,
+	0x1498: 0x000c, 0x1499: 0x000c, 0x149a: 0x000c, 0x149b: 0x000c, 0x149c: 0x000c, 0x149d: 0x000c,
+	0x149e: 0x000c, 0x149f: 0x000c, 0x14a0: 0x000c, 0x14a1: 0x000c, 0x14a2: 0x000c, 0x14a3: 0x000c,
+	0x14a4: 0x000c, 0x14a5: 0x000c, 0x14a6: 0x000c, 0x14a7: 0x000c, 0x14a8: 0x000c, 0x14a9: 0x000c,
+	0x14aa: 0x000c, 0x14ab: 0x000c, 0x14ac: 0x000c, 0x14ad: 0x000c, 0x14ae: 0x000c, 0x14af: 0x000c,
+	0x14b0: 0x000c,
+	// Block 0x53, offset 0x14c0
+	0x14c0: 0x000a, 0x14c1: 0x000a, 0x14c3: 0x000a, 0x14c4: 0x000a, 0x14c5: 0x000a,
+	0x14c6: 0x000a, 0x14c8: 0x000a, 0x14c9: 0x000a,
+	0x14d4: 0x000a, 0x14d6: 0x000a, 0x14d7: 0x000a,
+	0x14d8: 0x000a,
+	0x14de: 0x000a, 0x14df: 0x000a, 0x14e0: 0x000a, 0x14e1: 0x000a, 0x14e2: 0x000a, 0x14e3: 0x000a,
+	0x14e5: 0x000a, 0x14e7: 0x000a, 0x14e9: 0x000a,
+	0x14ee: 0x0004,
+	0x14fa: 0x000a, 0x14fb: 0x000a,
+	// Block 0x54, offset 0x1500
+	0x1500: 0x000a, 0x1501: 0x000a, 0x1502: 0x000a, 0x1503: 0x000a, 0x1504: 0x000a,
+	0x150a: 0x000a, 0x150b: 0x000a,
+	0x150c: 0x000a, 0x150d: 0x000a, 0x1510: 0x000a, 0x1511: 0x000a,
+	0x1512: 0x000a, 0x1513: 0x000a, 0x1514: 0x000a, 0x1515: 0x000a, 0x1516: 0x000a, 0x1517: 0x000a,
+	0x1518: 0x000a, 0x1519: 0x000a, 0x151a: 0x000a, 0x151b: 0x000a, 0x151c: 0x000a, 0x151d: 0x000a,
+	0x151e: 0x000a, 0x151f: 0x000a,
+	// Block 0x55, offset 0x1540
+	0x1549: 0x000a, 0x154a: 0x000a, 0x154b: 0x000a,
+	0x1550: 0x000a, 0x1551: 0x000a,
+	0x1552: 0x000a, 0x1553: 0x000a, 0x1554: 0x000a, 0x1555: 0x000a, 0x1556: 0x000a, 0x1557: 0x000a,
+	0x1558: 0x000a, 0x1559: 0x000a, 0x155a: 0x000a, 0x155b: 0x000a, 0x155c: 0x000a, 0x155d: 0x000a,
+	0x155e: 0x000a, 0x155f: 0x000a, 0x1560: 0x000a, 0x1561: 0x000a, 0x1562: 0x000a, 0x1563: 0x000a,
+	0x1564: 0x000a, 0x1565: 0x000a, 0x1566: 0x000a, 0x1567: 0x000a, 0x1568: 0x000a, 0x1569: 0x000a,
+	0x156a: 0x000a, 0x156b: 0x000a, 0x156c: 0x000a, 0x156d: 0x000a, 0x156e: 0x000a, 0x156f: 0x000a,
+	0x1570: 0x000a, 0x1571: 0x000a, 0x1572: 0x000a, 0x1573: 0x000a, 0x1574: 0x000a, 0x1575: 0x000a,
+	0x1576: 0x000a, 0x1577: 0x000a, 0x1578: 0x000a, 0x1579: 0x000a, 0x157a: 0x000a, 0x157b: 0x000a,
+	0x157c: 0x000a, 0x157d: 0x000a, 0x157e: 0x000a, 0x157f: 0x000a,
+	// Block 0x56, offset 0x1580
+	0x1580: 0x000a, 0x1581: 0x000a, 0x1582: 0x000a, 0x1583: 0x000a, 0x1584: 0x000a, 0x1585: 0x000a,
+	0x1586: 0x000a, 0x1587: 0x000a, 0x1588: 0x000a, 0x1589: 0x000a, 0x158a: 0x000a, 0x158b: 0x000a,
+	0x158c: 0x000a, 0x158d: 0x000a, 0x158e: 0x000a, 0x158f: 0x000a, 0x1590: 0x000a, 0x1591: 0x000a,
+	0x1592: 0x000a, 0x1593: 0x000a, 0x1594: 0x000a, 0x1595: 0x000a, 0x1596: 0x000a, 0x1597: 0x000a,
+	0x1598: 0x000a, 0x1599: 0x000a, 0x159a: 0x000a, 0x159b: 0x000a, 0x159c: 0x000a, 0x159d: 0x000a,
+	0x159e: 0x000a, 0x159f: 0x000a, 0x15a0: 0x000a, 0x15a1: 0x000a, 0x15a2: 0x000a, 0x15a3: 0x000a,
+	0x15a4: 0x000a, 0x15a5: 0x000a, 0x15a6: 0x000a, 0x15a7: 0x000a, 0x15a8: 0x000a, 0x15a9: 0x000a,
+	0x15aa: 0x000a, 0x15ab: 0x000a, 0x15ac: 0x000a, 0x15ad: 0x000a, 0x15ae: 0x000a, 0x15af: 0x000a,
+	0x15b0: 0x000a, 0x15b1: 0x000a, 0x15b2: 0x000a, 0x15b3: 0x000a, 0x15b4: 0x000a, 0x15b5: 0x000a,
+	0x15b6: 0x000a, 0x15b7: 0x000a, 0x15b8: 0x000a, 0x15b9: 0x000a, 0x15ba: 0x000a, 0x15bb: 0x000a,
+	0x15bc: 0x000a, 0x15bd: 0x000a, 0x15be: 0x000a, 0x15bf: 0x000a,
+	// Block 0x57, offset 0x15c0
+	0x15c0: 0x000a, 0x15c1: 0x000a, 0x15c2: 0x000a, 0x15c3: 0x000a, 0x15c4: 0x000a, 0x15c5: 0x000a,
+	0x15c6: 0x000a, 0x15c7: 0x000a, 0x15c8: 0x000a, 0x15c9: 0x000a, 0x15ca: 0x000a, 0x15cb: 0x000a,
+	0x15cc: 0x000a, 0x15cd: 0x000a, 0x15ce: 0x000a, 0x15cf: 0x000a, 0x15d0: 0x000a, 0x15d1: 0x000a,
+	0x15d2: 0x0003, 0x15d3: 0x0004, 0x15d4: 0x000a, 0x15d5: 0x000a, 0x15d6: 0x000a, 0x15d7: 0x000a,
+	0x15d8: 0x000a, 0x15d9: 0x000a, 0x15da: 0x000a, 0x15db: 0x000a, 0x15dc: 0x000a, 0x15dd: 0x000a,
+	0x15de: 0x000a, 0x15df: 0x000a, 0x15e0: 0x000a, 0x15e1: 0x000a, 0x15e2: 0x000a, 0x15e3: 0x000a,
+	0x15e4: 0x000a, 0x15e5: 0x000a, 0x15e6: 0x000a, 0x15e7: 0x000a, 0x15e8: 0x000a, 0x15e9: 0x000a,
+	0x15ea: 0x000a, 0x15eb: 0x000a, 0x15ec: 0x000a, 0x15ed: 0x000a, 0x15ee: 0x000a, 0x15ef: 0x000a,
+	0x15f0: 0x000a, 0x15f1: 0x000a, 0x15f2: 0x000a, 0x15f3: 0x000a, 0x15f4: 0x000a, 0x15f5: 0x000a,
+	0x15f6: 0x000a, 0x15f7: 0x000a, 0x15f8: 0x000a, 0x15f9: 0x000a, 0x15fa: 0x000a, 0x15fb: 0x000a,
+	0x15fc: 0x000a, 0x15fd: 0x000a, 0x15fe: 0x000a, 0x15ff: 0x000a,
+	// Block 0x58, offset 0x1600
+	0x1600: 0x000a, 0x1601: 0x000a, 0x1602: 0x000a, 0x1603: 0x000a, 0x1604: 0x000a, 0x1605: 0x000a,
+	0x1606: 0x000a, 0x1607: 0x000a, 0x1608: 0x003a, 0x1609: 0x002a, 0x160a: 0x003a, 0x160b: 0x002a,
+	0x160c: 0x000a, 0x160d: 0x000a, 0x160e: 0x000a, 0x160f: 0x000a, 0x1610: 0x000a, 0x1611: 0x000a,
+	0x1612: 0x000a, 0x1613: 0x000a, 0x1614: 0x000a, 0x1615: 0x000a, 0x1616: 0x000a, 0x1617: 0x000a,
+	0x1618: 0x000a, 0x1619: 0x000a, 0x161a: 0x000a, 0x161b: 0x000a, 0x161c: 0x000a, 0x161d: 0x000a,
+	0x161e: 0x000a, 0x161f: 0x000a, 0x1620: 0x000a, 0x1621: 0x000a, 0x1622: 0x000a, 0x1623: 0x000a,
+	0x1624: 0x000a, 0x1625: 0x000a, 0x1626: 0x000a, 0x1627: 0x000a, 0x1628: 0x000a, 0x1629: 0x009a,
+	0x162a: 0x008a, 0x162b: 0x000a, 0x162c: 0x000a, 0x162d: 0x000a, 0x162e: 0x000a, 0x162f: 0x000a,
+	0x1630: 0x000a, 0x1631: 0x000a, 0x1632: 0x000a, 0x1633: 0x000a, 0x1634: 0x000a, 0x1635: 0x000a,
+	// Block 0x59, offset 0x1640
+	0x167b: 0x000a,
+	0x167c: 0x000a, 0x167d: 0x000a, 0x167e: 0x000a, 0x167f: 0x000a,
+	// Block 0x5a, offset 0x1680
+	0x1680: 0x000a, 0x1681: 0x000a, 0x1682: 0x000a, 0x1683: 0x000a, 0x1684: 0x000a, 0x1685: 0x000a,
+	0x1686: 0x000a, 0x1687: 0x000a, 0x1688: 0x000a, 0x1689: 0x000a, 0x168a: 0x000a, 0x168b: 0x000a,
+	0x168c: 0x000a, 0x168d: 0x000a, 0x168e: 0x000a, 0x168f: 0x000a, 0x1690: 0x000a, 0x1691: 0x000a,
+	0x1692: 0x000a, 0x1693: 0x000a, 0x1694: 0x000a, 0x1696: 0x000a, 0x1697: 0x000a,
+	0x1698: 0x000a, 0x1699: 0x000a, 0x169a: 0x000a, 0x169b: 0x000a, 0x169c: 0x000a, 0x169d: 0x000a,
+	0x169e: 0x000a, 0x169f: 0x000a, 0x16a0: 0x000a, 0x16a1: 0x000a, 0x16a2: 0x000a, 0x16a3: 0x000a,
+	0x16a4: 0x000a, 0x16a5: 0x000a, 0x16a6: 0x000a, 0x16a7: 0x000a, 0x16a8: 0x000a, 0x16a9: 0x000a,
+	0x16aa: 0x000a, 0x16ab: 0x000a, 0x16ac: 0x000a, 0x16ad: 0x000a, 0x16ae: 0x000a, 0x16af: 0x000a,
+	0x16b0: 0x000a, 0x16b1: 0x000a, 0x16b2: 0x000a, 0x16b3: 0x000a, 0x16b4: 0x000a, 0x16b5: 0x000a,
+	0x16b6: 0x000a, 0x16b7: 0x000a, 0x16b8: 0x000a, 0x16b9: 0x000a, 0x16ba: 0x000a, 0x16bb: 0x000a,
+	0x16bc: 0x000a, 0x16bd: 0x000a, 0x16be: 0x000a, 0x16bf: 0x000a,
+	// Block 0x5b, offset 0x16c0
+	0x16c0: 0x000a, 0x16c1: 0x000a, 0x16c2: 0x000a, 0x16c3: 0x000a, 0x16c4: 0x000a, 0x16c5: 0x000a,
+	0x16c6: 0x000a, 0x16c7: 0x000a, 0x16c8: 0x000a, 0x16c9: 0x000a, 0x16ca: 0x000a, 0x16cb: 0x000a,
+	0x16cc: 0x000a, 0x16cd: 0x000a, 0x16ce: 0x000a, 0x16cf: 0x000a, 0x16d0: 0x000a, 0x16d1: 0x000a,
+	0x16d2: 0x000a, 0x16d3: 0x000a, 0x16d4: 0x000a, 0x16d5: 0x000a, 0x16d6: 0x000a, 0x16d7: 0x000a,
+	0x16d8: 0x000a, 0x16d9: 0x000a, 0x16da: 0x000a, 0x16db: 0x000a, 0x16dc: 0x000a, 0x16dd: 0x000a,
+	0x16de: 0x000a, 0x16df: 0x000a, 0x16e0: 0x000a, 0x16e1: 0x000a, 0x16e2: 0x000a, 0x16e3: 0x000a,
+	0x16e4: 0x000a, 0x16e5: 0x000a, 0x16e6: 0x000a, 0x16e7: 0x000a, 0x16e8: 0x000a, 0x16e9: 0x000a,
+	0x16ea: 0x000a, 0x16eb: 0x000a, 0x16ec: 0x000a, 0x16ed: 0x000a, 0x16ee: 0x000a, 0x16ef: 0x000a,
+	0x16f0: 0x000a, 0x16f1: 0x000a, 0x16f2: 0x000a, 0x16f3: 0x000a, 0x16f4: 0x000a, 0x16f5: 0x000a,
+	0x16f6: 0x000a, 0x16f7: 0x000a, 0x16f8: 0x000a, 0x16f9: 0x000a, 0x16fa: 0x000a, 0x16fb: 0x000a,
+	0x16fc: 0x000a, 0x16fd: 0x000a, 0x16fe: 0x000a,
+	// Block 0x5c, offset 0x1700
+	0x1700: 0x000a, 0x1701: 0x000a, 0x1702: 0x000a, 0x1703: 0x000a, 0x1704: 0x000a, 0x1705: 0x000a,
+	0x1706: 0x000a, 0x1707: 0x000a, 0x1708: 0x000a, 0x1709: 0x000a, 0x170a: 0x000a, 0x170b: 0x000a,
+	0x170c: 0x000a, 0x170d: 0x000a, 0x170e: 0x000a, 0x170f: 0x000a, 0x1710: 0x000a, 0x1711: 0x000a,
+	0x1712: 0x000a, 0x1713: 0x000a, 0x1714: 0x000a, 0x1715: 0x000a, 0x1716: 0x000a, 0x1717: 0x000a,
+	0x1718: 0x000a, 0x1719: 0x000a, 0x171a: 0x000a, 0x171b: 0x000a, 0x171c: 0x000a, 0x171d: 0x000a,
+	0x171e: 0x000a, 0x171f: 0x000a, 0x1720: 0x000a, 0x1721: 0x000a, 0x1722: 0x000a, 0x1723: 0x000a,
+	0x1724: 0x000a, 0x1725: 0x000a, 0x1726: 0x000a,
+	// Block 0x5d, offset 0x1740
+	0x1740: 0x000a, 0x1741: 0x000a, 0x1742: 0x000a, 0x1743: 0x000a, 0x1744: 0x000a, 0x1745: 0x000a,
+	0x1746: 0x000a, 0x1747: 0x000a, 0x1748: 0x000a, 0x1749: 0x000a, 0x174a: 0x000a,
+	0x1760: 0x000a, 0x1761: 0x000a, 0x1762: 0x000a, 0x1763: 0x000a,
+	0x1764: 0x000a, 0x1765: 0x000a, 0x1766: 0x000a, 0x1767: 0x000a, 0x1768: 0x000a, 0x1769: 0x000a,
+	0x176a: 0x000a, 0x176b: 0x000a, 0x176c: 0x000a, 0x176d: 0x000a, 0x176e: 0x000a, 0x176f: 0x000a,
+	0x1770: 0x000a, 0x1771: 0x000a, 0x1772: 0x000a, 0x1773: 0x000a, 0x1774: 0x000a, 0x1775: 0x000a,
+	0x1776: 0x000a, 0x1777: 0x000a, 0x1778: 0x000a, 0x1779: 0x000a, 0x177a: 0x000a, 0x177b: 0x000a,
+	0x177c: 0x000a, 0x177d: 0x000a, 0x177e: 0x000a, 0x177f: 0x000a,
+	// Block 0x5e, offset 0x1780
+	0x1780: 0x000a, 0x1781: 0x000a, 0x1782: 0x000a, 0x1783: 0x000a, 0x1784: 0x000a, 0x1785: 0x000a,
+	0x1786: 0x000a, 0x1787: 0x000a, 0x1788: 0x0002, 0x1789: 0x0002, 0x178a: 0x0002, 0x178b: 0x0002,
+	0x178c: 0x0002, 0x178d: 0x0002, 0x178e: 0x0002, 0x178f: 0x0002, 0x1790: 0x0002, 0x1791: 0x0002,
+	0x1792: 0x0002, 0x1793: 0x0002, 0x1794: 0x0002, 0x1795: 0x0002, 0x1796: 0x0002, 0x1797: 0x0002,
+	0x1798: 0x0002, 0x1799: 0x0002, 0x179a: 0x0002, 0x179b: 0x0002,
+	// Block 0x5f, offset 0x17c0
+	0x17ea: 0x000a, 0x17eb: 0x000a, 0x17ec: 0x000a, 0x17ed: 0x000a, 0x17ee: 0x000a, 0x17ef: 0x000a,
+	0x17f0: 0x000a, 0x17f1: 0x000a, 0x17f2: 0x000a, 0x17f3: 0x000a, 0x17f4: 0x000a, 0x17f5: 0x000a,
+	0x17f6: 0x000a, 0x17f7: 0x000a, 0x17f8: 0x000a, 0x17f9: 0x000a, 0x17fa: 0x000a, 0x17fb: 0x000a,
+	0x17fc: 0x000a, 0x17fd: 0x000a, 0x17fe: 0x000a, 0x17ff: 0x000a,
+	// Block 0x60, offset 0x1800
+	0x1800: 0x000a, 0x1801: 0x000a, 0x1802: 0x000a, 0x1803: 0x000a, 0x1804: 0x000a, 0x1805: 0x000a,
+	0x1806: 0x000a, 0x1807: 0x000a, 0x1808: 0x000a, 0x1809: 0x000a, 0x180a: 0x000a, 0x180b: 0x000a,
+	0x180c: 0x000a, 0x180d: 0x000a, 0x180e: 0x000a, 0x180f: 0x000a, 0x1810: 0x000a, 0x1811: 0x000a,
+	0x1812: 0x000a, 0x1813: 0x000a, 0x1814: 0x000a, 0x1815: 0x000a, 0x1816: 0x000a, 0x1817: 0x000a,
+	0x1818: 0x000a, 0x1819: 0x000a, 0x181a: 0x000a, 0x181b: 0x000a, 0x181c: 0x000a, 0x181d: 0x000a,
+	0x181e: 0x000a, 0x181f: 0x000a, 0x1820: 0x000a, 0x1821: 0x000a, 0x1822: 0x000a, 0x1823: 0x000a,
+	0x1824: 0x000a, 0x1825: 0x000a, 0x1826: 0x000a, 0x1827: 0x000a, 0x1828: 0x000a, 0x1829: 0x000a,
+	0x182a: 0x000a, 0x182b: 0x000a, 0x182d: 0x000a, 0x182e: 0x000a, 0x182f: 0x000a,
+	0x1830: 0x000a, 0x1831: 0x000a, 0x1832: 0x000a, 0x1833: 0x000a, 0x1834: 0x000a, 0x1835: 0x000a,
+	0x1836: 0x000a, 0x1837: 0x000a, 0x1838: 0x000a, 0x1839: 0x000a, 0x183a: 0x000a, 0x183b: 0x000a,
+	0x183c: 0x000a, 0x183d: 0x000a, 0x183e: 0x000a, 0x183f: 0x000a,
+	// Block 0x61, offset 0x1840
+	0x1840: 0x000a, 0x1841: 0x000a, 0x1842: 0x000a, 0x1843: 0x000a, 0x1844: 0x000a, 0x1845: 0x000a,
+	0x1846: 0x000a, 0x1847: 0x000a, 0x1848: 0x000a, 0x1849: 0x000a, 0x184a: 0x000a, 0x184b: 0x000a,
+	0x184c: 0x000a, 0x184d: 0x000a, 0x184e: 0x000a, 0x184f: 0x000a, 0x1850: 0x000a, 0x1851: 0x000a,
+	0x1852: 0x000a, 0x1853: 0x000a, 0x1854: 0x000a, 0x1855: 0x000a, 0x1856: 0x000a, 0x1857: 0x000a,
+	0x1858: 0x000a, 0x1859: 0x000a, 0x185a: 0x000a, 0x185b: 0x000a, 0x185c: 0x000a, 0x185d: 0x000a,
+	0x185e: 0x000a, 0x185f: 0x000a, 0x1860: 0x000a, 0x1861: 0x000a, 0x1862: 0x000a, 0x1863: 0x000a,
+	0x1864: 0x000a, 0x1865: 0x000a, 0x1866: 0x000a, 0x1867: 0x000a, 0x1868: 0x003a, 0x1869: 0x002a,
+	0x186a: 0x003a, 0x186b: 0x002a, 0x186c: 0x003a, 0x186d: 0x002a, 0x186e: 0x003a, 0x186f: 0x002a,
+	0x1870: 0x003a, 0x1871: 0x002a, 0x1872: 0x003a, 0x1873: 0x002a, 0x1874: 0x003a, 0x1875: 0x002a,
+	0x1876: 0x000a, 0x1877: 0x000a, 0x1878: 0x000a, 0x1879: 0x000a, 0x187a: 0x000a, 0x187b: 0x000a,
+	0x187c: 0x000a, 0x187d: 0x000a, 0x187e: 0x000a, 0x187f: 0x000a,
+	// Block 0x62, offset 0x1880
+	0x1880: 0x000a, 0x1881: 0x000a, 0x1882: 0x000a, 0x1883: 0x000a, 0x1884: 0x000a, 0x1885: 0x009a,
+	0x1886: 0x008a, 0x1887: 0x000a, 0x1888: 0x000a, 0x1889: 0x000a, 0x188a: 0x000a, 0x188b: 0x000a,
+	0x188c: 0x000a, 0x188d: 0x000a, 0x188e: 0x000a, 0x188f: 0x000a, 0x1890: 0x000a, 0x1891: 0x000a,
+	0x1892: 0x000a, 0x1893: 0x000a, 0x1894: 0x000a, 0x1895: 0x000a, 0x1896: 0x000a, 0x1897: 0x000a,
+	0x1898: 0x000a, 0x1899: 0x000a, 0x189a: 0x000a, 0x189b: 0x000a, 0x189c: 0x000a, 0x189d: 0x000a,
+	0x189e: 0x000a, 0x189f: 0x000a, 0x18a0: 0x000a, 0x18a1: 0x000a, 0x18a2: 0x000a, 0x18a3: 0x000a,
+	0x18a4: 0x000a, 0x18a5: 0x000a, 0x18a6: 0x003a, 0x18a7: 0x002a, 0x18a8: 0x003a, 0x18a9: 0x002a,
+	0x18aa: 0x003a, 0x18ab: 0x002a, 0x18ac: 0x003a, 0x18ad: 0x002a, 0x18ae: 0x003a, 0x18af: 0x002a,
+	0x18b0: 0x000a, 0x18b1: 0x000a, 0x18b2: 0x000a, 0x18b3: 0x000a, 0x18b4: 0x000a, 0x18b5: 0x000a,
+	0x18b6: 0x000a, 0x18b7: 0x000a, 0x18b8: 0x000a, 0x18b9: 0x000a, 0x18ba: 0x000a, 0x18bb: 0x000a,
+	0x18bc: 0x000a, 0x18bd: 0x000a, 0x18be: 0x000a, 0x18bf: 0x000a,
+	// Block 0x63, offset 0x18c0
+	0x18c0: 0x000a, 0x18c1: 0x000a, 0x18c2: 0x000a, 0x18c3: 0x007a, 0x18c4: 0x006a, 0x18c5: 0x009a,
+	0x18c6: 0x008a, 0x18c7: 0x00ba, 0x18c8: 0x00aa, 0x18c9: 0x009a, 0x18ca: 0x008a, 0x18cb: 0x007a,
+	0x18cc: 0x006a, 0x18cd: 0x00da, 0x18ce: 0x002a, 0x18cf: 0x003a, 0x18d0: 0x00ca, 0x18d1: 0x009a,
+	0x18d2: 0x008a, 0x18d3: 0x007a, 0x18d4: 0x006a, 0x18d5: 0x009a, 0x18d6: 0x008a, 0x18d7: 0x00ba,
+	0x18d8: 0x00aa, 0x18d9: 0x000a, 0x18da: 0x000a, 0x18db: 0x000a, 0x18dc: 0x000a, 0x18dd: 0x000a,
+	0x18de: 0x000a, 0x18df: 0x000a, 0x18e0: 0x000a, 0x18e1: 0x000a, 0x18e2: 0x000a, 0x18e3: 0x000a,
+	0x18e4: 0x000a, 0x18e5: 0x000a, 0x18e6: 0x000a, 0x18e7: 0x000a, 0x18e8: 0x000a, 0x18e9: 0x000a,
+	0x18ea: 0x000a, 0x18eb: 0x000a, 0x18ec: 0x000a, 0x18ed: 0x000a, 0x18ee: 0x000a, 0x18ef: 0x000a,
+	0x18f0: 0x000a, 0x18f1: 0x000a, 0x18f2: 0x000a, 0x18f3: 0x000a, 0x18f4: 0x000a, 0x18f5: 0x000a,
+	0x18f6: 0x000a, 0x18f7: 0x000a, 0x18f8: 0x000a, 0x18f9: 0x000a, 0x18fa: 0x000a, 0x18fb: 0x000a,
+	0x18fc: 0x000a, 0x18fd: 0x000a, 0x18fe: 0x000a, 0x18ff: 0x000a,
+	// Block 0x64, offset 0x1900
+	0x1900: 0x000a, 0x1901: 0x000a, 0x1902: 0x000a, 0x1903: 0x000a, 0x1904: 0x000a, 0x1905: 0x000a,
+	0x1906: 0x000a, 0x1907: 0x000a, 0x1908: 0x000a, 0x1909: 0x000a, 0x190a: 0x000a, 0x190b: 0x000a,
+	0x190c: 0x000a, 0x190d: 0x000a, 0x190e: 0x000a, 0x190f: 0x000a, 0x1910: 0x000a, 0x1911: 0x000a,
+	0x1912: 0x000a, 0x1913: 0x000a, 0x1914: 0x000a, 0x1915: 0x000a, 0x1916: 0x000a, 0x1917: 0x000a,
+	0x1918: 0x003a, 0x1919: 0x002a, 0x191a: 0x003a, 0x191b: 0x002a, 0x191c: 0x000a, 0x191d: 0x000a,
+	0x191e: 0x000a, 0x191f: 0x000a, 0x1920: 0x000a, 0x1921: 0x000a, 0x1922: 0x000a, 0x1923: 0x000a,
+	0x1924: 0x000a, 0x1925: 0x000a, 0x1926: 0x000a, 0x1927: 0x000a, 0x1928: 0x000a, 0x1929: 0x000a,
+	0x192a: 0x000a, 0x192b: 0x000a, 0x192c: 0x000a, 0x192d: 0x000a, 0x192e: 0x000a, 0x192f: 0x000a,
+	0x1930: 0x000a, 0x1931: 0x000a, 0x1932: 0x000a, 0x1933: 0x000a, 0x1934: 0x000a, 0x1935: 0x000a,
+	0x1936: 0x000a, 0x1937: 0x000a, 0x1938: 0x000a, 0x1939: 0x000a, 0x193a: 0x000a, 0x193b: 0x000a,
+	0x193c: 0x003a, 0x193d: 0x002a, 0x193e: 0x000a, 0x193f: 0x000a,
+	// Block 0x65, offset 0x1940
+	0x1940: 0x000a, 0x1941: 0x000a, 0x1942: 0x000a, 0x1943: 0x000a, 0x1944: 0x000a, 0x1945: 0x000a,
+	0x1946: 0x000a, 0x1947: 0x000a, 0x1948: 0x000a, 0x1949: 0x000a, 0x194a: 0x000a, 0x194b: 0x000a,
+	0x194c: 0x000a, 0x194d: 0x000a, 0x194e: 0x000a, 0x194f: 0x000a, 0x1950: 0x000a, 0x1951: 0x000a,
+	0x1952: 0x000a, 0x1953: 0x000a, 0x1954: 0x000a, 0x1955: 0x000a, 0x1956: 0x000a, 0x1957: 0x000a,
+	0x1958: 0x000a, 0x1959: 0x000a, 0x195a: 0x000a, 0x195b: 0x000a, 0x195c: 0x000a, 0x195d: 0x000a,
+	0x195e: 0x000a, 0x195f: 0x000a, 0x1960: 0x000a, 0x1961: 0x000a, 0x1962: 0x000a, 0x1963: 0x000a,
+	0x1964: 0x000a, 0x1965: 0x000a, 0x1966: 0x000a, 0x1967: 0x000a, 0x1968: 0x000a, 0x1969: 0x000a,
+	0x196a: 0x000a, 0x196b: 0x000a, 0x196c: 0x000a, 0x196d: 0x000a, 0x196e: 0x000a, 0x196f: 0x000a,
+	0x1970: 0x000a, 0x1971: 0x000a, 0x1972: 0x000a, 0x1973: 0x000a,
+	0x1976: 0x000a, 0x1977: 0x000a, 0x1978: 0x000a, 0x1979: 0x000a, 0x197a: 0x000a, 0x197b: 0x000a,
+	0x197c: 0x000a, 0x197d: 0x000a, 0x197e: 0x000a, 0x197f: 0x000a,
+	// Block 0x66, offset 0x1980
+	0x1980: 0x000a, 0x1981: 0x000a, 0x1982: 0x000a, 0x1983: 0x000a, 0x1984: 0x000a, 0x1985: 0x000a,
+	0x1986: 0x000a, 0x1987: 0x000a, 0x1988: 0x000a, 0x1989: 0x000a, 0x198a: 0x000a, 0x198b: 0x000a,
+	0x198c: 0x000a, 0x198d: 0x000a, 0x198e: 0x000a, 0x198f: 0x000a, 0x1990: 0x000a, 0x1991: 0x000a,
+	0x1992: 0x000a, 0x1993: 0x000a, 0x1994: 0x000a, 0x1995: 0x000a,
+	0x1998: 0x000a, 0x1999: 0x000a, 0x199a: 0x000a, 0x199b: 0x000a, 0x199c: 0x000a, 0x199d: 0x000a,
+	0x199e: 0x000a, 0x199f: 0x000a, 0x19a0: 0x000a, 0x19a1: 0x000a, 0x19a2: 0x000a, 0x19a3: 0x000a,
+	0x19a4: 0x000a, 0x19a5: 0x000a, 0x19a6: 0x000a, 0x19a7: 0x000a, 0x19a8: 0x000a, 0x19a9: 0x000a,
+	0x19aa: 0x000a, 0x19ab: 0x000a, 0x19ac: 0x000a, 0x19ad: 0x000a, 0x19ae: 0x000a, 0x19af: 0x000a,
+	0x19b0: 0x000a, 0x19b1: 0x000a, 0x19b2: 0x000a, 0x19b3: 0x000a, 0x19b4: 0x000a, 0x19b5: 0x000a,
+	0x19b6: 0x000a, 0x19b7: 0x000a, 0x19b8: 0x000a, 0x19b9: 0x000a,
+	0x19bd: 0x000a, 0x19be: 0x000a, 0x19bf: 0x000a,
+	// Block 0x67, offset 0x19c0
+	0x19c0: 0x000a, 0x19c1: 0x000a, 0x19c2: 0x000a, 0x19c3: 0x000a, 0x19c4: 0x000a, 0x19c5: 0x000a,
+	0x19c6: 0x000a, 0x19c7: 0x000a, 0x19c8: 0x000a, 0x19ca: 0x000a, 0x19cb: 0x000a,
+	0x19cc: 0x000a, 0x19cd: 0x000a, 0x19ce: 0x000a, 0x19cf: 0x000a, 0x19d0: 0x000a, 0x19d1: 0x000a,
+	0x19ec: 0x000a, 0x19ed: 0x000a, 0x19ee: 0x000a, 0x19ef: 0x000a,
+	// Block 0x68, offset 0x1a00
+	0x1a25: 0x000a, 0x1a26: 0x000a, 0x1a27: 0x000a, 0x1a28: 0x000a, 0x1a29: 0x000a,
+	0x1a2a: 0x000a, 0x1a2f: 0x000c,
+	0x1a30: 0x000c, 0x1a31: 0x000c,
+	0x1a39: 0x000a, 0x1a3a: 0x000a, 0x1a3b: 0x000a,
+	0x1a3c: 0x000a, 0x1a3d: 0x000a, 0x1a3e: 0x000a, 0x1a3f: 0x000a,
+	// Block 0x69, offset 0x1a40
+	0x1a7f: 0x000c,
+	// Block 0x6a, offset 0x1a80
+	0x1aa0: 0x000c, 0x1aa1: 0x000c, 0x1aa2: 0x000c, 0x1aa3: 0x000c,
+	0x1aa4: 0x000c, 0x1aa5: 0x000c, 0x1aa6: 0x000c, 0x1aa7: 0x000c, 0x1aa8: 0x000c, 0x1aa9: 0x000c,
+	0x1aaa: 0x000c, 0x1aab: 0x000c, 0x1aac: 0x000c, 0x1aad: 0x000c, 0x1aae: 0x000c, 0x1aaf: 0x000c,
+	0x1ab0: 0x000c, 0x1ab1: 0x000c, 0x1ab2: 0x000c, 0x1ab3: 0x000c, 0x1ab4: 0x000c, 0x1ab5: 0x000c,
+	0x1ab6: 0x000c, 0x1ab7: 0x000c, 0x1ab8: 0x000c, 0x1ab9: 0x000c, 0x1aba: 0x000c, 0x1abb: 0x000c,
+	0x1abc: 0x000c, 0x1abd: 0x000c, 0x1abe: 0x000c, 0x1abf: 0x000c,
+	// Block 0x6b, offset 0x1ac0
+	0x1ac0: 0x000a, 0x1ac1: 0x000a, 0x1ac2: 0x000a, 0x1ac3: 0x000a, 0x1ac4: 0x000a, 0x1ac5: 0x000a,
+	0x1ac6: 0x000a, 0x1ac7: 0x000a, 0x1ac8: 0x000a, 0x1ac9: 0x000a, 0x1aca: 0x000a, 0x1acb: 0x000a,
+	0x1acc: 0x000a, 0x1acd: 0x000a, 0x1ace: 0x000a, 0x1acf: 0x000a, 0x1ad0: 0x000a, 0x1ad1: 0x000a,
+	0x1ad2: 0x000a, 0x1ad3: 0x000a, 0x1ad4: 0x000a, 0x1ad5: 0x000a, 0x1ad6: 0x000a, 0x1ad7: 0x000a,
+	0x1ad8: 0x000a, 0x1ad9: 0x000a, 0x1ada: 0x000a, 0x1adb: 0x000a, 0x1adc: 0x000a, 0x1add: 0x000a,
+	0x1ade: 0x000a, 0x1adf: 0x000a, 0x1ae0: 0x000a, 0x1ae1: 0x000a, 0x1ae2: 0x003a, 0x1ae3: 0x002a,
+	0x1ae4: 0x003a, 0x1ae5: 0x002a, 0x1ae6: 0x003a, 0x1ae7: 0x002a, 0x1ae8: 0x003a, 0x1ae9: 0x002a,
+	0x1aea: 0x000a, 0x1aeb: 0x000a, 0x1aec: 0x000a, 0x1aed: 0x000a, 0x1aee: 0x000a, 0x1aef: 0x000a,
+	0x1af0: 0x000a, 0x1af1: 0x000a, 0x1af2: 0x000a, 0x1af3: 0x000a, 0x1af4: 0x000a, 0x1af5: 0x000a,
+	0x1af6: 0x000a, 0x1af7: 0x000a, 0x1af8: 0x000a, 0x1af9: 0x000a, 0x1afa: 0x000a, 0x1afb: 0x000a,
+	0x1afc: 0x000a, 0x1afd: 0x000a, 0x1afe: 0x000a, 0x1aff: 0x000a,
+	// Block 0x6c, offset 0x1b00
+	0x1b00: 0x000a, 0x1b01: 0x000a, 0x1b02: 0x000a, 0x1b03: 0x000a, 0x1b04: 0x000a,
+	// Block 0x6d, offset 0x1b40
+	0x1b40: 0x000a, 0x1b41: 0x000a, 0x1b42: 0x000a, 0x1b43: 0x000a, 0x1b44: 0x000a, 0x1b45: 0x000a,
+	0x1b46: 0x000a, 0x1b47: 0x000a, 0x1b48: 0x000a, 0x1b49: 0x000a, 0x1b4a: 0x000a, 0x1b4b: 0x000a,
+	0x1b4c: 0x000a, 0x1b4d: 0x000a, 0x1b4e: 0x000a, 0x1b4f: 0x000a, 0x1b50: 0x000a, 0x1b51: 0x000a,
+	0x1b52: 0x000a, 0x1b53: 0x000a, 0x1b54: 0x000a, 0x1b55: 0x000a, 0x1b56: 0x000a, 0x1b57: 0x000a,
+	0x1b58: 0x000a, 0x1b59: 0x000a, 0x1b5b: 0x000a, 0x1b5c: 0x000a, 0x1b5d: 0x000a,
+	0x1b5e: 0x000a, 0x1b5f: 0x000a, 0x1b60: 0x000a, 0x1b61: 0x000a, 0x1b62: 0x000a, 0x1b63: 0x000a,
+	0x1b64: 0x000a, 0x1b65: 0x000a, 0x1b66: 0x000a, 0x1b67: 0x000a, 0x1b68: 0x000a, 0x1b69: 0x000a,
+	0x1b6a: 0x000a, 0x1b6b: 0x000a, 0x1b6c: 0x000a, 0x1b6d: 0x000a, 0x1b6e: 0x000a, 0x1b6f: 0x000a,
+	0x1b70: 0x000a, 0x1b71: 0x000a, 0x1b72: 0x000a, 0x1b73: 0x000a, 0x1b74: 0x000a, 0x1b75: 0x000a,
+	0x1b76: 0x000a, 0x1b77: 0x000a, 0x1b78: 0x000a, 0x1b79: 0x000a, 0x1b7a: 0x000a, 0x1b7b: 0x000a,
+	0x1b7c: 0x000a, 0x1b7d: 0x000a, 0x1b7e: 0x000a, 0x1b7f: 0x000a,
+	// Block 0x6e, offset 0x1b80
+	0x1b80: 0x000a, 0x1b81: 0x000a, 0x1b82: 0x000a, 0x1b83: 0x000a, 0x1b84: 0x000a, 0x1b85: 0x000a,
+	0x1b86: 0x000a, 0x1b87: 0x000a, 0x1b88: 0x000a, 0x1b89: 0x000a, 0x1b8a: 0x000a, 0x1b8b: 0x000a,
+	0x1b8c: 0x000a, 0x1b8d: 0x000a, 0x1b8e: 0x000a, 0x1b8f: 0x000a, 0x1b90: 0x000a, 0x1b91: 0x000a,
+	0x1b92: 0x000a, 0x1b93: 0x000a, 0x1b94: 0x000a, 0x1b95: 0x000a, 0x1b96: 0x000a, 0x1b97: 0x000a,
+	0x1b98: 0x000a, 0x1b99: 0x000a, 0x1b9a: 0x000a, 0x1b9b: 0x000a, 0x1b9c: 0x000a, 0x1b9d: 0x000a,
+	0x1b9e: 0x000a, 0x1b9f: 0x000a, 0x1ba0: 0x000a, 0x1ba1: 0x000a, 0x1ba2: 0x000a, 0x1ba3: 0x000a,
+	0x1ba4: 0x000a, 0x1ba5: 0x000a, 0x1ba6: 0x000a, 0x1ba7: 0x000a, 0x1ba8: 0x000a, 0x1ba9: 0x000a,
+	0x1baa: 0x000a, 0x1bab: 0x000a, 0x1bac: 0x000a, 0x1bad: 0x000a, 0x1bae: 0x000a, 0x1baf: 0x000a,
+	0x1bb0: 0x000a, 0x1bb1: 0x000a, 0x1bb2: 0x000a, 0x1bb3: 0x000a,
+	// Block 0x6f, offset 0x1bc0
+	0x1bc0: 0x000a, 0x1bc1: 0x000a, 0x1bc2: 0x000a, 0x1bc3: 0x000a, 0x1bc4: 0x000a, 0x1bc5: 0x000a,
+	0x1bc6: 0x000a, 0x1bc7: 0x000a, 0x1bc8: 0x000a, 0x1bc9: 0x000a, 0x1bca: 0x000a, 0x1bcb: 0x000a,
+	0x1bcc: 0x000a, 0x1bcd: 0x000a, 0x1bce: 0x000a, 0x1bcf: 0x000a, 0x1bd0: 0x000a, 0x1bd1: 0x000a,
+	0x1bd2: 0x000a, 0x1bd3: 0x000a, 0x1bd4: 0x000a, 0x1bd5: 0x000a,
+	0x1bf0: 0x000a, 0x1bf1: 0x000a, 0x1bf2: 0x000a, 0x1bf3: 0x000a, 0x1bf4: 0x000a, 0x1bf5: 0x000a,
+	0x1bf6: 0x000a, 0x1bf7: 0x000a, 0x1bf8: 0x000a, 0x1bf9: 0x000a, 0x1bfa: 0x000a, 0x1bfb: 0x000a,
+	// Block 0x70, offset 0x1c00
+	0x1c00: 0x0009, 0x1c01: 0x000a, 0x1c02: 0x000a, 0x1c03: 0x000a, 0x1c04: 0x000a,
+	0x1c08: 0x003a, 0x1c09: 0x002a, 0x1c0a: 0x003a, 0x1c0b: 0x002a,
+	0x1c0c: 0x003a, 0x1c0d: 0x002a, 0x1c0e: 0x003a, 0x1c0f: 0x002a, 0x1c10: 0x003a, 0x1c11: 0x002a,
+	0x1c12: 0x000a, 0x1c13: 0x000a, 0x1c14: 0x003a, 0x1c15: 0x002a, 0x1c16: 0x003a, 0x1c17: 0x002a,
+	0x1c18: 0x003a, 0x1c19: 0x002a, 0x1c1a: 0x003a, 0x1c1b: 0x002a, 0x1c1c: 0x000a, 0x1c1d: 0x000a,
+	0x1c1e: 0x000a, 0x1c1f: 0x000a, 0x1c20: 0x000a,
+	0x1c2a: 0x000c, 0x1c2b: 0x000c, 0x1c2c: 0x000c, 0x1c2d: 0x000c,
+	0x1c30: 0x000a,
+	0x1c36: 0x000a, 0x1c37: 0x000a,
+	0x1c3d: 0x000a, 0x1c3e: 0x000a, 0x1c3f: 0x000a,
+	// Block 0x71, offset 0x1c40
+	0x1c59: 0x000c, 0x1c5a: 0x000c, 0x1c5b: 0x000a, 0x1c5c: 0x000a,
+	0x1c60: 0x000a,
+	// Block 0x72, offset 0x1c80
+	0x1cbb: 0x000a,
+	// Block 0x73, offset 0x1cc0
+	0x1cc0: 0x000a, 0x1cc1: 0x000a, 0x1cc2: 0x000a, 0x1cc3: 0x000a, 0x1cc4: 0x000a, 0x1cc5: 0x000a,
+	0x1cc6: 0x000a, 0x1cc7: 0x000a, 0x1cc8: 0x000a, 0x1cc9: 0x000a, 0x1cca: 0x000a, 0x1ccb: 0x000a,
+	0x1ccc: 0x000a, 0x1ccd: 0x000a, 0x1cce: 0x000a, 0x1ccf: 0x000a, 0x1cd0: 0x000a, 0x1cd1: 0x000a,
+	0x1cd2: 0x000a, 0x1cd3: 0x000a, 0x1cd4: 0x000a, 0x1cd5: 0x000a, 0x1cd6: 0x000a, 0x1cd7: 0x000a,
+	0x1cd8: 0x000a, 0x1cd9: 0x000a, 0x1cda: 0x000a, 0x1cdb: 0x000a, 0x1cdc: 0x000a, 0x1cdd: 0x000a,
+	0x1cde: 0x000a, 0x1cdf: 0x000a, 0x1ce0: 0x000a, 0x1ce1: 0x000a, 0x1ce2: 0x000a, 0x1ce3: 0x000a,
+	// Block 0x74, offset 0x1d00
+	0x1d1d: 0x000a,
+	0x1d1e: 0x000a,
+	// Block 0x75, offset 0x1d40
+	0x1d50: 0x000a, 0x1d51: 0x000a,
+	0x1d52: 0x000a, 0x1d53: 0x000a, 0x1d54: 0x000a, 0x1d55: 0x000a, 0x1d56: 0x000a, 0x1d57: 0x000a,
+	0x1d58: 0x000a, 0x1d59: 0x000a, 0x1d5a: 0x000a, 0x1d5b: 0x000a, 0x1d5c: 0x000a, 0x1d5d: 0x000a,
+	0x1d5e: 0x000a, 0x1d5f: 0x000a,
+	0x1d7c: 0x000a, 0x1d7d: 0x000a, 0x1d7e: 0x000a,
+	// Block 0x76, offset 0x1d80
+	0x1db1: 0x000a, 0x1db2: 0x000a, 0x1db3: 0x000a, 0x1db4: 0x000a, 0x1db5: 0x000a,
+	0x1db6: 0x000a, 0x1db7: 0x000a, 0x1db8: 0x000a, 0x1db9: 0x000a, 0x1dba: 0x000a, 0x1dbb: 0x000a,
+	0x1dbc: 0x000a, 0x1dbd: 0x000a, 0x1dbe: 0x000a, 0x1dbf: 0x000a,
+	// Block 0x77, offset 0x1dc0
+	0x1dcc: 0x000a, 0x1dcd: 0x000a, 0x1dce: 0x000a, 0x1dcf: 0x000a,
+	// Block 0x78, offset 0x1e00
+	0x1e37: 0x000a, 0x1e38: 0x000a, 0x1e39: 0x000a, 0x1e3a: 0x000a,
+	// Block 0x79, offset 0x1e40
+	0x1e5e: 0x000a, 0x1e5f: 0x000a,
+	0x1e7f: 0x000a,
+	// Block 0x7a, offset 0x1e80
+	0x1e90: 0x000a, 0x1e91: 0x000a,
+	0x1e92: 0x000a, 0x1e93: 0x000a, 0x1e94: 0x000a, 0x1e95: 0x000a, 0x1e96: 0x000a, 0x1e97: 0x000a,
+	0x1e98: 0x000a, 0x1e99: 0x000a, 0x1e9a: 0x000a, 0x1e9b: 0x000a, 0x1e9c: 0x000a, 0x1e9d: 0x000a,
+	0x1e9e: 0x000a, 0x1e9f: 0x000a, 0x1ea0: 0x000a, 0x1ea1: 0x000a, 0x1ea2: 0x000a, 0x1ea3: 0x000a,
+	0x1ea4: 0x000a, 0x1ea5: 0x000a, 0x1ea6: 0x000a, 0x1ea7: 0x000a, 0x1ea8: 0x000a, 0x1ea9: 0x000a,
+	0x1eaa: 0x000a, 0x1eab: 0x000a, 0x1eac: 0x000a, 0x1ead: 0x000a, 0x1eae: 0x000a, 0x1eaf: 0x000a,
+	0x1eb0: 0x000a, 0x1eb1: 0x000a, 0x1eb2: 0x000a, 0x1eb3: 0x000a, 0x1eb4: 0x000a, 0x1eb5: 0x000a,
+	0x1eb6: 0x000a, 0x1eb7: 0x000a, 0x1eb8: 0x000a, 0x1eb9: 0x000a, 0x1eba: 0x000a, 0x1ebb: 0x000a,
+	0x1ebc: 0x000a, 0x1ebd: 0x000a, 0x1ebe: 0x000a, 0x1ebf: 0x000a,
+	// Block 0x7b, offset 0x1ec0
+	0x1ec0: 0x000a, 0x1ec1: 0x000a, 0x1ec2: 0x000a, 0x1ec3: 0x000a, 0x1ec4: 0x000a, 0x1ec5: 0x000a,
+	0x1ec6: 0x000a,
+	// Block 0x7c, offset 0x1f00
+	0x1f0d: 0x000a, 0x1f0e: 0x000a, 0x1f0f: 0x000a,
+	// Block 0x7d, offset 0x1f40
+	0x1f6f: 0x000c,
+	0x1f70: 0x000c, 0x1f71: 0x000c, 0x1f72: 0x000c, 0x1f73: 0x000a, 0x1f74: 0x000c, 0x1f75: 0x000c,
+	0x1f76: 0x000c, 0x1f77: 0x000c, 0x1f78: 0x000c, 0x1f79: 0x000c, 0x1f7a: 0x000c, 0x1f7b: 0x000c,
+	0x1f7c: 0x000c, 0x1f7d: 0x000c, 0x1f7e: 0x000a, 0x1f7f: 0x000a,
+	// Block 0x7e, offset 0x1f80
+	0x1f9e: 0x000c, 0x1f9f: 0x000c,
+	// Block 0x7f, offset 0x1fc0
+	0x1ff0: 0x000c, 0x1ff1: 0x000c,
+	// Block 0x80, offset 0x2000
+	0x2000: 0x000a, 0x2001: 0x000a, 0x2002: 0x000a, 0x2003: 0x000a, 0x2004: 0x000a, 0x2005: 0x000a,
+	0x2006: 0x000a, 0x2007: 0x000a, 0x2008: 0x000a, 0x2009: 0x000a, 0x200a: 0x000a, 0x200b: 0x000a,
+	0x200c: 0x000a, 0x200d: 0x000a, 0x200e: 0x000a, 0x200f: 0x000a, 0x2010: 0x000a, 0x2011: 0x000a,
+	0x2012: 0x000a, 0x2013: 0x000a, 0x2014: 0x000a, 0x2015: 0x000a, 0x2016: 0x000a, 0x2017: 0x000a,
+	0x2018: 0x000a, 0x2019: 0x000a, 0x201a: 0x000a, 0x201b: 0x000a, 0x201c: 0x000a, 0x201d: 0x000a,
+	0x201e: 0x000a, 0x201f: 0x000a, 0x2020: 0x000a, 0x2021: 0x000a,
+	// Block 0x81, offset 0x2040
+	0x2048: 0x000a,
+	// Block 0x82, offset 0x2080
+	0x2082: 0x000c,
+	0x2086: 0x000c, 0x208b: 0x000c,
+	0x20a5: 0x000c, 0x20a6: 0x000c, 0x20a8: 0x000a, 0x20a9: 0x000a,
+	0x20aa: 0x000a, 0x20ab: 0x000a,
+	0x20b8: 0x0004, 0x20b9: 0x0004,
+	// Block 0x83, offset 0x20c0
+	0x20f4: 0x000a, 0x20f5: 0x000a,
+	0x20f6: 0x000a, 0x20f7: 0x000a,
+	// Block 0x84, offset 0x2100
+	0x2104: 0x000c, 0x2105: 0x000c,
+	0x2120: 0x000c, 0x2121: 0x000c, 0x2122: 0x000c, 0x2123: 0x000c,
+	0x2124: 0x000c, 0x2125: 0x000c, 0x2126: 0x000c, 0x2127: 0x000c, 0x2128: 0x000c, 0x2129: 0x000c,
+	0x212a: 0x000c, 0x212b: 0x000c, 0x212c: 0x000c, 0x212d: 0x000c, 0x212e: 0x000c, 0x212f: 0x000c,
+	0x2130: 0x000c, 0x2131: 0x000c,
+	// Block 0x85, offset 0x2140
+	0x2166: 0x000c, 0x2167: 0x000c, 0x2168: 0x000c, 0x2169: 0x000c,
+	0x216a: 0x000c, 0x216b: 0x000c, 0x216c: 0x000c, 0x216d: 0x000c,
+	// Block 0x86, offset 0x2180
+	0x2187: 0x000c, 0x2188: 0x000c, 0x2189: 0x000c, 0x218a: 0x000c, 0x218b: 0x000c,
+	0x218c: 0x000c, 0x218d: 0x000c, 0x218e: 0x000c, 0x218f: 0x000c, 0x2190: 0x000c, 0x2191: 0x000c,
+	// Block 0x87, offset 0x21c0
+	0x21c0: 0x000c, 0x21c1: 0x000c, 0x21c2: 0x000c,
+	0x21f3: 0x000c,
+	0x21f6: 0x000c, 0x21f7: 0x000c, 0x21f8: 0x000c, 0x21f9: 0x000c,
+	0x21fc: 0x000c,
+	// Block 0x88, offset 0x2200
+	0x2225: 0x000c,
+	// Block 0x89, offset 0x2240
+	0x2269: 0x000c,
+	0x226a: 0x000c, 0x226b: 0x000c, 0x226c: 0x000c, 0x226d: 0x000c, 0x226e: 0x000c,
+	0x2271: 0x000c, 0x2272: 0x000c, 0x2275: 0x000c,
+	0x2276: 0x000c,
+	// Block 0x8a, offset 0x2280
+	0x2283: 0x000c,
+	0x228c: 0x000c,
+	0x22bc: 0x000c,
+	// Block 0x8b, offset 0x22c0
+	0x22f0: 0x000c, 0x22f2: 0x000c, 0x22f3: 0x000c, 0x22f4: 0x000c,
+	0x22f7: 0x000c, 0x22f8: 0x000c,
+	0x22fe: 0x000c, 0x22ff: 0x000c,
+	// Block 0x8c, offset 0x2300
+	0x2301: 0x000c,
+	0x232c: 0x000c, 0x232d: 0x000c,
+	0x2336: 0x000c,
+	// Block 0x8d, offset 0x2340
+	0x2365: 0x000c, 0x2368: 0x000c,
+	0x236d: 0x000c,
+	// Block 0x8e, offset 0x2380
+	0x239d: 0x0001,
+	0x239e: 0x000c, 0x239f: 0x0001, 0x23a0: 0x0001, 0x23a1: 0x0001, 0x23a2: 0x0001, 0x23a3: 0x0001,
+	0x23a4: 0x0001, 0x23a5: 0x0001, 0x23a6: 0x0001, 0x23a7: 0x0001, 0x23a8: 0x0001, 0x23a9: 0x0003,
+	0x23aa: 0x0001, 0x23ab: 0x0001, 0x23ac: 0x0001, 0x23ad: 0x0001, 0x23ae: 0x0001, 0x23af: 0x0001,
+	0x23b0: 0x0001, 0x23b1: 0x0001, 0x23b2: 0x0001, 0x23b3: 0x0001, 0x23b4: 0x0001, 0x23b5: 0x0001,
+	0x23b6: 0x0001, 0x23b7: 0x0001, 0x23b8: 0x0001, 0x23b9: 0x0001, 0x23ba: 0x0001, 0x23bb: 0x0001,
+	0x23bc: 0x0001, 0x23bd: 0x0001, 0x23be: 0x0001, 0x23bf: 0x0001,
+	// Block 0x8f, offset 0x23c0
+	0x23c0: 0x0001, 0x23c1: 0x0001, 0x23c2: 0x0001, 0x23c3: 0x0001, 0x23c4: 0x0001, 0x23c5: 0x0001,
+	0x23c6: 0x0001, 0x23c7: 0x0001, 0x23c8: 0x0001, 0x23c9: 0x0001, 0x23ca: 0x0001, 0x23cb: 0x0001,
+	0x23cc: 0x0001, 0x23cd: 0x0001, 0x23ce: 0x0001, 0x23cf: 0x0001, 0x23d0: 0x000d, 0x23d1: 0x000d,
+	0x23d2: 0x000d, 0x23d3: 0x000d, 0x23d4: 0x000d, 0x23d5: 0x000d, 0x23d6: 0x000d, 0x23d7: 0x000d,
+	0x23d8: 0x000d, 0x23d9: 0x000d, 0x23da: 0x000d, 0x23db: 0x000d, 0x23dc: 0x000d, 0x23dd: 0x000d,
+	0x23de: 0x000d, 0x23df: 0x000d, 0x23e0: 0x000d, 0x23e1: 0x000d, 0x23e2: 0x000d, 0x23e3: 0x000d,
+	0x23e4: 0x000d, 0x23e5: 0x000d, 0x23e6: 0x000d, 0x23e7: 0x000d, 0x23e8: 0x000d, 0x23e9: 0x000d,
+	0x23ea: 0x000d, 0x23eb: 0x000d, 0x23ec: 0x000d, 0x23ed: 0x000d, 0x23ee: 0x000d, 0x23ef: 0x000d,
+	0x23f0: 0x000d, 0x23f1: 0x000d, 0x23f2: 0x000d, 0x23f3: 0x000d, 0x23f4: 0x000d, 0x23f5: 0x000d,
+	0x23f6: 0x000d, 0x23f7: 0x000d, 0x23f8: 0x000d, 0x23f9: 0x000d, 0x23fa: 0x000d, 0x23fb: 0x000d,
+	0x23fc: 0x000d, 0x23fd: 0x000d, 0x23fe: 0x000d, 0x23ff: 0x000d,
+	// Block 0x90, offset 0x2400
+	0x2400: 0x000d, 0x2401: 0x000d, 0x2402: 0x000d, 0x2403: 0x000d, 0x2404: 0x000d, 0x2405: 0x000d,
+	0x2406: 0x000d, 0x2407: 0x000d, 0x2408: 0x000d, 0x2409: 0x000d, 0x240a: 0x000d, 0x240b: 0x000d,
+	0x240c: 0x000d, 0x240d: 0x000d, 0x240e: 0x000d, 0x240f: 0x000d, 0x2410: 0x000d, 0x2411: 0x000d,
+	0x2412: 0x000d, 0x2413: 0x000d, 0x2414: 0x000d, 0x2415: 0x000d, 0x2416: 0x000d, 0x2417: 0x000d,
+	0x2418: 0x000d, 0x2419: 0x000d, 0x241a: 0x000d, 0x241b: 0x000d, 0x241c: 0x000d, 0x241d: 0x000d,
+	0x241e: 0x000d, 0x241f: 0x000d, 0x2420: 0x000d, 0x2421: 0x000d, 0x2422: 0x000d, 0x2423: 0x000d,
+	0x2424: 0x000d, 0x2425: 0x000d, 0x2426: 0x000d, 0x2427: 0x000d, 0x2428: 0x000d, 0x2429: 0x000d,
+	0x242a: 0x000d, 0x242b: 0x000d, 0x242c: 0x000d, 0x242d: 0x000d, 0x242e: 0x000d, 0x242f: 0x000d,
+	0x2430: 0x000d, 0x2431: 0x000d, 0x2432: 0x000d, 0x2433: 0x000d, 0x2434: 0x000d, 0x2435: 0x000d,
+	0x2436: 0x000d, 0x2437: 0x000d, 0x2438: 0x000d, 0x2439: 0x000d, 0x243a: 0x000d, 0x243b: 0x000d,
+	0x243c: 0x000d, 0x243d: 0x000d, 0x243e: 0x000a, 0x243f: 0x000a,
+	// Block 0x91, offset 0x2440
+	0x2440: 0x000d, 0x2441: 0x000d, 0x2442: 0x000d, 0x2443: 0x000d, 0x2444: 0x000d, 0x2445: 0x000d,
+	0x2446: 0x000d, 0x2447: 0x000d, 0x2448: 0x000d, 0x2449: 0x000d, 0x244a: 0x000d, 0x244b: 0x000d,
+	0x244c: 0x000d, 0x244d: 0x000d, 0x244e: 0x000d, 0x244f: 0x000d, 0x2450: 0x000b, 0x2451: 0x000b,
+	0x2452: 0x000b, 0x2453: 0x000b, 0x2454: 0x000b, 0x2455: 0x000b, 0x2456: 0x000b, 0x2457: 0x000b,
+	0x2458: 0x000b, 0x2459: 0x000b, 0x245a: 0x000b, 0x245b: 0x000b, 0x245c: 0x000b, 0x245d: 0x000b,
+	0x245e: 0x000b, 0x245f: 0x000b, 0x2460: 0x000b, 0x2461: 0x000b, 0x2462: 0x000b, 0x2463: 0x000b,
+	0x2464: 0x000b, 0x2465: 0x000b, 0x2466: 0x000b, 0x2467: 0x000b, 0x2468: 0x000b, 0x2469: 0x000b,
+	0x246a: 0x000b, 0x246b: 0x000b, 0x246c: 0x000b, 0x246d: 0x000b, 0x246e: 0x000b, 0x246f: 0x000b,
+	0x2470: 0x000d, 0x2471: 0x000d, 0x2472: 0x000d, 0x2473: 0x000d, 0x2474: 0x000d, 0x2475: 0x000d,
+	0x2476: 0x000d, 0x2477: 0x000d, 0x2478: 0x000d, 0x2479: 0x000d, 0x247a: 0x000d, 0x247b: 0x000d,
+	0x247c: 0x000d, 0x247d: 0x000a, 0x247e: 0x000d, 0x247f: 0x000d,
+	// Block 0x92, offset 0x2480
+	0x2480: 0x000c, 0x2481: 0x000c, 0x2482: 0x000c, 0x2483: 0x000c, 0x2484: 0x000c, 0x2485: 0x000c,
+	0x2486: 0x000c, 0x2487: 0x000c, 0x2488: 0x000c, 0x2489: 0x000c, 0x248a: 0x000c, 0x248b: 0x000c,
+	0x248c: 0x000c, 0x248d: 0x000c, 0x248e: 0x000c, 0x248f: 0x000c, 0x2490: 0x000a, 0x2491: 0x000a,
+	0x2492: 0x000a, 0x2493: 0x000a, 0x2494: 0x000a, 0x2495: 0x000a, 0x2496: 0x000a, 0x2497: 0x000a,
+	0x2498: 0x000a, 0x2499: 0x000a,
+	0x24a0: 0x000c, 0x24a1: 0x000c, 0x24a2: 0x000c, 0x24a3: 0x000c,
+	0x24a4: 0x000c, 0x24a5: 0x000c, 0x24a6: 0x000c, 0x24a7: 0x000c, 0x24a8: 0x000c, 0x24a9: 0x000c,
+	0x24aa: 0x000c, 0x24ab: 0x000c, 0x24ac: 0x000c, 0x24ad: 0x000c, 0x24ae: 0x000c, 0x24af: 0x000c,
+	0x24b0: 0x000a, 0x24b1: 0x000a, 0x24b2: 0x000a, 0x24b3: 0x000a, 0x24b4: 0x000a, 0x24b5: 0x000a,
+	0x24b6: 0x000a, 0x24b7: 0x000a, 0x24b8: 0x000a, 0x24b9: 0x000a, 0x24ba: 0x000a, 0x24bb: 0x000a,
+	0x24bc: 0x000a, 0x24bd: 0x000a, 0x24be: 0x000a, 0x24bf: 0x000a,
+	// Block 0x93, offset 0x24c0
+	0x24c0: 0x000a, 0x24c1: 0x000a, 0x24c2: 0x000a, 0x24c3: 0x000a, 0x24c4: 0x000a, 0x24c5: 0x000a,
+	0x24c6: 0x000a, 0x24c7: 0x000a, 0x24c8: 0x000a, 0x24c9: 0x000a, 0x24ca: 0x000a, 0x24cb: 0x000a,
+	0x24cc: 0x000a, 0x24cd: 0x000a, 0x24ce: 0x000a, 0x24cf: 0x000a, 0x24d0: 0x0006, 0x24d1: 0x000a,
+	0x24d2: 0x0006, 0x24d4: 0x000a, 0x24d5: 0x0006, 0x24d6: 0x000a, 0x24d7: 0x000a,
+	0x24d8: 0x000a, 0x24d9: 0x009a, 0x24da: 0x008a, 0x24db: 0x007a, 0x24dc: 0x006a, 0x24dd: 0x009a,
+	0x24de: 0x008a, 0x24df: 0x0004, 0x24e0: 0x000a, 0x24e1: 0x000a, 0x24e2: 0x0003, 0x24e3: 0x0003,
+	0x24e4: 0x000a, 0x24e5: 0x000a, 0x24e6: 0x000a, 0x24e8: 0x000a, 0x24e9: 0x0004,
+	0x24ea: 0x0004, 0x24eb: 0x000a,
+	0x24f0: 0x000d, 0x24f1: 0x000d, 0x24f2: 0x000d, 0x24f3: 0x000d, 0x24f4: 0x000d, 0x24f5: 0x000d,
+	0x24f6: 0x000d, 0x24f7: 0x000d, 0x24f8: 0x000d, 0x24f9: 0x000d, 0x24fa: 0x000d, 0x24fb: 0x000d,
+	0x24fc: 0x000d, 0x24fd: 0x000d, 0x24fe: 0x000d, 0x24ff: 0x000d,
+	// Block 0x94, offset 0x2500
+	0x2500: 0x000d, 0x2501: 0x000d, 0x2502: 0x000d, 0x2503: 0x000d, 0x2504: 0x000d, 0x2505: 0x000d,
+	0x2506: 0x000d, 0x2507: 0x000d, 0x2508: 0x000d, 0x2509: 0x000d, 0x250a: 0x000d, 0x250b: 0x000d,
+	0x250c: 0x000d, 0x250d: 0x000d, 0x250e: 0x000d, 0x250f: 0x000d, 0x2510: 0x000d, 0x2511: 0x000d,
+	0x2512: 0x000d, 0x2513: 0x000d, 0x2514: 0x000d, 0x2515: 0x000d, 0x2516: 0x000d, 0x2517: 0x000d,
+	0x2518: 0x000d, 0x2519: 0x000d, 0x251a: 0x000d, 0x251b: 0x000d, 0x251c: 0x000d, 0x251d: 0x000d,
+	0x251e: 0x000d, 0x251f: 0x000d, 0x2520: 0x000d, 0x2521: 0x000d, 0x2522: 0x000d, 0x2523: 0x000d,
+	0x2524: 0x000d, 0x2525: 0x000d, 0x2526: 0x000d, 0x2527: 0x000d, 0x2528: 0x000d, 0x2529: 0x000d,
+	0x252a: 0x000d, 0x252b: 0x000d, 0x252c: 0x000d, 0x252d: 0x000d, 0x252e: 0x000d, 0x252f: 0x000d,
+	0x2530: 0x000d, 0x2531: 0x000d, 0x2532: 0x000d, 0x2533: 0x000d, 0x2534: 0x000d, 0x2535: 0x000d,
+	0x2536: 0x000d, 0x2537: 0x000d, 0x2538: 0x000d, 0x2539: 0x000d, 0x253a: 0x000d, 0x253b: 0x000d,
+	0x253c: 0x000d, 0x253d: 0x000d, 0x253e: 0x000d, 0x253f: 0x000b,
+	// Block 0x95, offset 0x2540
+	0x2541: 0x000a, 0x2542: 0x000a, 0x2543: 0x0004, 0x2544: 0x0004, 0x2545: 0x0004,
+	0x2546: 0x000a, 0x2547: 0x000a, 0x2548: 0x003a, 0x2549: 0x002a, 0x254a: 0x000a, 0x254b: 0x0003,
+	0x254c: 0x0006, 0x254d: 0x0003, 0x254e: 0x0006, 0x254f: 0x0006, 0x2550: 0x0002, 0x2551: 0x0002,
+	0x2552: 0x0002, 0x2553: 0x0002, 0x2554: 0x0002, 0x2555: 0x0002, 0x2556: 0x0002, 0x2557: 0x0002,
+	0x2558: 0x0002, 0x2559: 0x0002, 0x255a: 0x0006, 0x255b: 0x000a, 0x255c: 0x000a, 0x255d: 0x000a,
+	0x255e: 0x000a, 0x255f: 0x000a, 0x2560: 0x000a,
+	0x257b: 0x005a,
+	0x257c: 0x000a, 0x257d: 0x004a, 0x257e: 0x000a, 0x257f: 0x000a,
+	// Block 0x96, offset 0x2580
+	0x2580: 0x000a,
+	0x259b: 0x005a, 0x259c: 0x000a, 0x259d: 0x004a,
+	0x259e: 0x000a, 0x259f: 0x00fa, 0x25a0: 0x00ea, 0x25a1: 0x000a, 0x25a2: 0x003a, 0x25a3: 0x002a,
+	0x25a4: 0x000a, 0x25a5: 0x000a,
+	// Block 0x97, offset 0x25c0
+	0x25e0: 0x0004, 0x25e1: 0x0004, 0x25e2: 0x000a, 0x25e3: 0x000a,
+	0x25e4: 0x000a, 0x25e5: 0x0004, 0x25e6: 0x0004, 0x25e8: 0x000a, 0x25e9: 0x000a,
+	0x25ea: 0x000a, 0x25eb: 0x000a, 0x25ec: 0x000a, 0x25ed: 0x000a, 0x25ee: 0x000a,
+	0x25f0: 0x000b, 0x25f1: 0x000b, 0x25f2: 0x000b, 0x25f3: 0x000b, 0x25f4: 0x000b, 0x25f5: 0x000b,
+	0x25f6: 0x000b, 0x25f7: 0x000b, 0x25f8: 0x000b, 0x25f9: 0x000a, 0x25fa: 0x000a, 0x25fb: 0x000a,
+	0x25fc: 0x000a, 0x25fd: 0x000a, 0x25fe: 0x000b, 0x25ff: 0x000b,
+	// Block 0x98, offset 0x2600
+	0x2601: 0x000a,
+	// Block 0x99, offset 0x2640
+	0x2640: 0x000a, 0x2641: 0x000a, 0x2642: 0x000a, 0x2643: 0x000a, 0x2644: 0x000a, 0x2645: 0x000a,
+	0x2646: 0x000a, 0x2647: 0x000a, 0x2648: 0x000a, 0x2649: 0x000a, 0x264a: 0x000a, 0x264b: 0x000a,
+	0x264c: 0x000a, 0x2650: 0x000a, 0x2651: 0x000a,
+	0x2652: 0x000a, 0x2653: 0x000a, 0x2654: 0x000a, 0x2655: 0x000a, 0x2656: 0x000a, 0x2657: 0x000a,
+	0x2658: 0x000a, 0x2659: 0x000a, 0x265a: 0x000a, 0x265b: 0x000a,
+	0x2660: 0x000a,
+	// Block 0x9a, offset 0x2680
+	0x26bd: 0x000c,
+	// Block 0x9b, offset 0x26c0
+	0x26e0: 0x000c, 0x26e1: 0x0002, 0x26e2: 0x0002, 0x26e3: 0x0002,
+	0x26e4: 0x0002, 0x26e5: 0x0002, 0x26e6: 0x0002, 0x26e7: 0x0002, 0x26e8: 0x0002, 0x26e9: 0x0002,
+	0x26ea: 0x0002, 0x26eb: 0x0002, 0x26ec: 0x0002, 0x26ed: 0x0002, 0x26ee: 0x0002, 0x26ef: 0x0002,
+	0x26f0: 0x0002, 0x26f1: 0x0002, 0x26f2: 0x0002, 0x26f3: 0x0002, 0x26f4: 0x0002, 0x26f5: 0x0002,
+	0x26f6: 0x0002, 0x26f7: 0x0002, 0x26f8: 0x0002, 0x26f9: 0x0002, 0x26fa: 0x0002, 0x26fb: 0x0002,
+	// Block 0x9c, offset 0x2700
+	0x2736: 0x000c, 0x2737: 0x000c, 0x2738: 0x000c, 0x2739: 0x000c, 0x273a: 0x000c,
+	// Block 0x9d, offset 0x2740
+	0x2740: 0x0001, 0x2741: 0x0001, 0x2742: 0x0001, 0x2743: 0x0001, 0x2744: 0x0001, 0x2745: 0x0001,
+	0x2746: 0x0001, 0x2747: 0x0001, 0x2748: 0x0001, 0x2749: 0x0001, 0x274a: 0x0001, 0x274b: 0x0001,
+	0x274c: 0x0001, 0x274d: 0x0001, 0x274e: 0x0001, 0x274f: 0x0001, 0x2750: 0x0001, 0x2751: 0x0001,
+	0x2752: 0x0001, 0x2753: 0x0001, 0x2754: 0x0001, 0x2755: 0x0001, 0x2756: 0x0001, 0x2757: 0x0001,
+	0x2758: 0x0001, 0x2759: 0x0001, 0x275a: 0x0001, 0x275b: 0x0001, 0x275c: 0x0001, 0x275d: 0x0001,
+	0x275e: 0x0001, 0x275f: 0x0001, 0x2760: 0x0001, 0x2761: 0x0001, 0x2762: 0x0001, 0x2763: 0x0001,
+	0x2764: 0x0001, 0x2765: 0x0001, 0x2766: 0x0001, 0x2767: 0x0001, 0x2768: 0x0001, 0x2769: 0x0001,
+	0x276a: 0x0001, 0x276b: 0x0001, 0x276c: 0x0001, 0x276d: 0x0001, 0x276e: 0x0001, 0x276f: 0x0001,
+	0x2770: 0x0001, 0x2771: 0x0001, 0x2772: 0x0001, 0x2773: 0x0001, 0x2774: 0x0001, 0x2775: 0x0001,
+	0x2776: 0x0001, 0x2777: 0x0001, 0x2778: 0x0001, 0x2779: 0x0001, 0x277a: 0x0001, 0x277b: 0x0001,
+	0x277c: 0x0001, 0x277d: 0x0001, 0x277e: 0x0001, 0x277f: 0x0001,
+	// Block 0x9e, offset 0x2780
+	0x2780: 0x0001, 0x2781: 0x0001, 0x2782: 0x0001, 0x2783: 0x0001, 0x2784: 0x0001, 0x2785: 0x0001,
+	0x2786: 0x0001, 0x2787: 0x0001, 0x2788: 0x0001, 0x2789: 0x0001, 0x278a: 0x0001, 0x278b: 0x0001,
+	0x278c: 0x0001, 0x278d: 0x0001, 0x278e: 0x0001, 0x278f: 0x0001, 0x2790: 0x0001, 0x2791: 0x0001,
+	0x2792: 0x0001, 0x2793: 0x0001, 0x2794: 0x0001, 0x2795: 0x0001, 0x2796: 0x0001, 0x2797: 0x0001,
+	0x2798: 0x0001, 0x2799: 0x0001, 0x279a: 0x0001, 0x279b: 0x0001, 0x279c: 0x0001, 0x279d: 0x0001,
+	0x279e: 0x0001, 0x279f: 0x000a, 0x27a0: 0x0001, 0x27a1: 0x0001, 0x27a2: 0x0001, 0x27a3: 0x0001,
+	0x27a4: 0x0001, 0x27a5: 0x0001, 0x27a6: 0x0001, 0x27a7: 0x0001, 0x27a8: 0x0001, 0x27a9: 0x0001,
+	0x27aa: 0x0001, 0x27ab: 0x0001, 0x27ac: 0x0001, 0x27ad: 0x0001, 0x27ae: 0x0001, 0x27af: 0x0001,
+	0x27b0: 0x0001, 0x27b1: 0x0001, 0x27b2: 0x0001, 0x27b3: 0x0001, 0x27b4: 0x0001, 0x27b5: 0x0001,
+	0x27b6: 0x0001, 0x27b7: 0x0001, 0x27b8: 0x0001, 0x27b9: 0x0001, 0x27ba: 0x0001, 0x27bb: 0x0001,
+	0x27bc: 0x0001, 0x27bd: 0x0001, 0x27be: 0x0001, 0x27bf: 0x0001,
+	// Block 0x9f, offset 0x27c0
+	0x27c0: 0x0001, 0x27c1: 0x000c, 0x27c2: 0x000c, 0x27c3: 0x000c, 0x27c4: 0x0001, 0x27c5: 0x000c,
+	0x27c6: 0x000c, 0x27c7: 0x0001, 0x27c8: 0x0001, 0x27c9: 0x0001, 0x27ca: 0x0001, 0x27cb: 0x0001,
+	0x27cc: 0x000c, 0x27cd: 0x000c, 0x27ce: 0x000c, 0x27cf: 0x000c, 0x27d0: 0x0001, 0x27d1: 0x0001,
+	0x27d2: 0x0001, 0x27d3: 0x0001, 0x27d4: 0x0001, 0x27d5: 0x0001, 0x27d6: 0x0001, 0x27d7: 0x0001,
+	0x27d8: 0x0001, 0x27d9: 0x0001, 0x27da: 0x0001, 0x27db: 0x0001, 0x27dc: 0x0001, 0x27dd: 0x0001,
+	0x27de: 0x0001, 0x27df: 0x0001, 0x27e0: 0x0001, 0x27e1: 0x0001, 0x27e2: 0x0001, 0x27e3: 0x0001,
+	0x27e4: 0x0001, 0x27e5: 0x0001, 0x27e6: 0x0001, 0x27e7: 0x0001, 0x27e8: 0x0001, 0x27e9: 0x0001,
+	0x27ea: 0x0001, 0x27eb: 0x0001, 0x27ec: 0x0001, 0x27ed: 0x0001, 0x27ee: 0x0001, 0x27ef: 0x0001,
+	0x27f0: 0x0001, 0x27f1: 0x0001, 0x27f2: 0x0001, 0x27f3: 0x0001, 0x27f4: 0x0001, 0x27f5: 0x0001,
+	0x27f6: 0x0001, 0x27f7: 0x0001, 0x27f8: 0x000c, 0x27f9: 0x000c, 0x27fa: 0x000c, 0x27fb: 0x0001,
+	0x27fc: 0x0001, 0x27fd: 0x0001, 0x27fe: 0x0001, 0x27ff: 0x000c,
+	// Block 0xa0, offset 0x2800
+	0x2800: 0x0001, 0x2801: 0x0001, 0x2802: 0x0001, 0x2803: 0x0001, 0x2804: 0x0001, 0x2805: 0x0001,
+	0x2806: 0x0001, 0x2807: 0x0001, 0x2808: 0x0001, 0x2809: 0x0001, 0x280a: 0x0001, 0x280b: 0x0001,
+	0x280c: 0x0001, 0x280d: 0x0001, 0x280e: 0x0001, 0x280f: 0x0001, 0x2810: 0x0001, 0x2811: 0x0001,
+	0x2812: 0x0001, 0x2813: 0x0001, 0x2814: 0x0001, 0x2815: 0x0001, 0x2816: 0x0001, 0x2817: 0x0001,
+	0x2818: 0x0001, 0x2819: 0x0001, 0x281a: 0x0001, 0x281b: 0x0001, 0x281c: 0x0001, 0x281d: 0x0001,
+	0x281e: 0x0001, 0x281f: 0x0001, 0x2820: 0x0001, 0x2821: 0x0001, 0x2822: 0x0001, 0x2823: 0x0001,
+	0x2824: 0x0001, 0x2825: 0x000c, 0x2826: 0x000c, 0x2827: 0x0001, 0x2828: 0x0001, 0x2829: 0x0001,
+	0x282a: 0x0001, 0x282b: 0x0001, 0x282c: 0x0001, 0x282d: 0x0001, 0x282e: 0x0001, 0x282f: 0x0001,
+	0x2830: 0x0001, 0x2831: 0x0001, 0x2832: 0x0001, 0x2833: 0x0001, 0x2834: 0x0001, 0x2835: 0x0001,
+	0x2836: 0x0001, 0x2837: 0x0001, 0x2838: 0x0001, 0x2839: 0x0001, 0x283a: 0x0001, 0x283b: 0x0001,
+	0x283c: 0x0001, 0x283d: 0x0001, 0x283e: 0x0001, 0x283f: 0x0001,
+	// Block 0xa1, offset 0x2840
+	0x2840: 0x0001, 0x2841: 0x0001, 0x2842: 0x0001, 0x2843: 0x0001, 0x2844: 0x0001, 0x2845: 0x0001,
+	0x2846: 0x0001, 0x2847: 0x0001, 0x2848: 0x0001, 0x2849: 0x0001, 0x284a: 0x0001, 0x284b: 0x0001,
+	0x284c: 0x0001, 0x284d: 0x0001, 0x284e: 0x0001, 0x284f: 0x0001, 0x2850: 0x0001, 0x2851: 0x0001,
+	0x2852: 0x0001, 0x2853: 0x0001, 0x2854: 0x0001, 0x2855: 0x0001, 0x2856: 0x0001, 0x2857: 0x0001,
+	0x2858: 0x0001, 0x2859: 0x0001, 0x285a: 0x0001, 0x285b: 0x0001, 0x285c: 0x0001, 0x285d: 0x0001,
+	0x285e: 0x0001, 0x285f: 0x0001, 0x2860: 0x0001, 0x2861: 0x0001, 0x2862: 0x0001, 0x2863: 0x0001,
+	0x2864: 0x0001, 0x2865: 0x0001, 0x2866: 0x0001, 0x2867: 0x0001, 0x2868: 0x0001, 0x2869: 0x0001,
+	0x286a: 0x0001, 0x286b: 0x0001, 0x286c: 0x0001, 0x286d: 0x0001, 0x286e: 0x0001, 0x286f: 0x0001,
+	0x2870: 0x0001, 0x2871: 0x0001, 0x2872: 0x0001, 0x2873: 0x0001, 0x2874: 0x0001, 0x2875: 0x0001,
+	0x2876: 0x0001, 0x2877: 0x0001, 0x2878: 0x0001, 0x2879: 0x000a, 0x287a: 0x000a, 0x287b: 0x000a,
+	0x287c: 0x000a, 0x287d: 0x000a, 0x287e: 0x000a, 0x287f: 0x000a,
+	// Block 0xa2, offset 0x2880
+	0x2880: 0x0001, 0x2881: 0x0001, 0x2882: 0x0001, 0x2883: 0x0001, 0x2884: 0x0001, 0x2885: 0x0001,
+	0x2886: 0x0001, 0x2887: 0x0001, 0x2888: 0x0001, 0x2889: 0x0001, 0x288a: 0x0001, 0x288b: 0x0001,
+	0x288c: 0x0001, 0x288d: 0x0001, 0x288e: 0x0001, 0x288f: 0x0001, 0x2890: 0x0001, 0x2891: 0x0001,
+	0x2892: 0x0001, 0x2893: 0x0001, 0x2894: 0x0001, 0x2895: 0x0001, 0x2896: 0x0001, 0x2897: 0x0001,
+	0x2898: 0x0001, 0x2899: 0x0001, 0x289a: 0x0001, 0x289b: 0x0001, 0x289c: 0x0001, 0x289d: 0x0001,
+	0x289e: 0x0001, 0x289f: 0x0001, 0x28a0: 0x0005, 0x28a1: 0x0005, 0x28a2: 0x0005, 0x28a3: 0x0005,
+	0x28a4: 0x0005, 0x28a5: 0x0005, 0x28a6: 0x0005, 0x28a7: 0x0005, 0x28a8: 0x0005, 0x28a9: 0x0005,
+	0x28aa: 0x0005, 0x28ab: 0x0005, 0x28ac: 0x0005, 0x28ad: 0x0005, 0x28ae: 0x0005, 0x28af: 0x0005,
+	0x28b0: 0x0005, 0x28b1: 0x0005, 0x28b2: 0x0005, 0x28b3: 0x0005, 0x28b4: 0x0005, 0x28b5: 0x0005,
+	0x28b6: 0x0005, 0x28b7: 0x0005, 0x28b8: 0x0005, 0x28b9: 0x0005, 0x28ba: 0x0005, 0x28bb: 0x0005,
+	0x28bc: 0x0005, 0x28bd: 0x0005, 0x28be: 0x0005, 0x28bf: 0x0001,
+	// Block 0xa3, offset 0x28c0
+	0x28c1: 0x000c,
+	0x28f8: 0x000c, 0x28f9: 0x000c, 0x28fa: 0x000c, 0x28fb: 0x000c,
+	0x28fc: 0x000c, 0x28fd: 0x000c, 0x28fe: 0x000c, 0x28ff: 0x000c,
+	// Block 0xa4, offset 0x2900
+	0x2900: 0x000c, 0x2901: 0x000c, 0x2902: 0x000c, 0x2903: 0x000c, 0x2904: 0x000c, 0x2905: 0x000c,
+	0x2906: 0x000c,
+	0x2912: 0x000a, 0x2913: 0x000a, 0x2914: 0x000a, 0x2915: 0x000a, 0x2916: 0x000a, 0x2917: 0x000a,
+	0x2918: 0x000a, 0x2919: 0x000a, 0x291a: 0x000a, 0x291b: 0x000a, 0x291c: 0x000a, 0x291d: 0x000a,
+	0x291e: 0x000a, 0x291f: 0x000a, 0x2920: 0x000a, 0x2921: 0x000a, 0x2922: 0x000a, 0x2923: 0x000a,
+	0x2924: 0x000a, 0x2925: 0x000a,
+	0x293f: 0x000c,
+	// Block 0xa5, offset 0x2940
+	0x2940: 0x000c, 0x2941: 0x000c,
+	0x2973: 0x000c, 0x2974: 0x000c, 0x2975: 0x000c,
+	0x2976: 0x000c, 0x2979: 0x000c, 0x297a: 0x000c,
+	// Block 0xa6, offset 0x2980
+	0x2980: 0x000c, 0x2981: 0x000c, 0x2982: 0x000c,
+	0x29a7: 0x000c, 0x29a8: 0x000c, 0x29a9: 0x000c,
+	0x29aa: 0x000c, 0x29ab: 0x000c, 0x29ad: 0x000c, 0x29ae: 0x000c, 0x29af: 0x000c,
+	0x29b0: 0x000c, 0x29b1: 0x000c, 0x29b2: 0x000c, 0x29b3: 0x000c, 0x29b4: 0x000c,
+	// Block 0xa7, offset 0x29c0
+	0x29f3: 0x000c,
+	// Block 0xa8, offset 0x2a00
+	0x2a00: 0x000c, 0x2a01: 0x000c,
+	0x2a36: 0x000c, 0x2a37: 0x000c, 0x2a38: 0x000c, 0x2a39: 0x000c, 0x2a3a: 0x000c, 0x2a3b: 0x000c,
+	0x2a3c: 0x000c, 0x2a3d: 0x000c, 0x2a3e: 0x000c,
+	// Block 0xa9, offset 0x2a40
+	0x2a4a: 0x000c, 0x2a4b: 0x000c,
+	0x2a4c: 0x000c,
+	// Block 0xaa, offset 0x2a80
+	0x2aaf: 0x000c,
+	0x2ab0: 0x000c, 0x2ab1: 0x000c, 0x2ab4: 0x000c,
+	0x2ab6: 0x000c, 0x2ab7: 0x000c,
+	0x2abe: 0x000c,
+	// Block 0xab, offset 0x2ac0
+	0x2adf: 0x000c, 0x2ae3: 0x000c,
+	0x2ae4: 0x000c, 0x2ae5: 0x000c, 0x2ae6: 0x000c, 0x2ae7: 0x000c, 0x2ae8: 0x000c, 0x2ae9: 0x000c,
+	0x2aea: 0x000c,
+	// Block 0xac, offset 0x2b00
+	0x2b00: 0x000c, 0x2b01: 0x000c,
+	0x2b3c: 0x000c,
+	// Block 0xad, offset 0x2b40
+	0x2b40: 0x000c,
+	0x2b66: 0x000c, 0x2b67: 0x000c, 0x2b68: 0x000c, 0x2b69: 0x000c,
+	0x2b6a: 0x000c, 0x2b6b: 0x000c, 0x2b6c: 0x000c,
+	0x2b70: 0x000c, 0x2b71: 0x000c, 0x2b72: 0x000c, 0x2b73: 0x000c, 0x2b74: 0x000c,
+	// Block 0xae, offset 0x2b80
+	0x2bb8: 0x000c, 0x2bb9: 0x000c, 0x2bba: 0x000c, 0x2bbb: 0x000c,
+	0x2bbc: 0x000c, 0x2bbd: 0x000c, 0x2bbe: 0x000c, 0x2bbf: 0x000c,
+	// Block 0xaf, offset 0x2bc0
+	0x2bc2: 0x000c, 0x2bc3: 0x000c, 0x2bc4: 0x000c,
+	0x2bc6: 0x000c,
+	// Block 0xb0, offset 0x2c00
+	0x2c33: 0x000c, 0x2c34: 0x000c, 0x2c35: 0x000c,
+	0x2c36: 0x000c, 0x2c37: 0x000c, 0x2c38: 0x000c, 0x2c3a: 0x000c,
+	0x2c3f: 0x000c,
+	// Block 0xb1, offset 0x2c40
+	0x2c40: 0x000c, 0x2c42: 0x000c, 0x2c43: 0x000c,
+	// Block 0xb2, offset 0x2c80
+	0x2cb2: 0x000c, 0x2cb3: 0x000c, 0x2cb4: 0x000c, 0x2cb5: 0x000c,
+	0x2cbc: 0x000c, 0x2cbd: 0x000c, 0x2cbf: 0x000c,
+	// Block 0xb3, offset 0x2cc0
+	0x2cc0: 0x000c,
+	0x2cdc: 0x000c, 0x2cdd: 0x000c,
+	// Block 0xb4, offset 0x2d00
+	0x2d33: 0x000c, 0x2d34: 0x000c, 0x2d35: 0x000c,
+	0x2d36: 0x000c, 0x2d37: 0x000c, 0x2d38: 0x000c, 0x2d39: 0x000c, 0x2d3a: 0x000c,
+	0x2d3d: 0x000c, 0x2d3f: 0x000c,
+	// Block 0xb5, offset 0x2d40
+	0x2d40: 0x000c,
+	0x2d60: 0x000a, 0x2d61: 0x000a, 0x2d62: 0x000a, 0x2d63: 0x000a,
+	0x2d64: 0x000a, 0x2d65: 0x000a, 0x2d66: 0x000a, 0x2d67: 0x000a, 0x2d68: 0x000a, 0x2d69: 0x000a,
+	0x2d6a: 0x000a, 0x2d6b: 0x000a, 0x2d6c: 0x000a,
+	// Block 0xb6, offset 0x2d80
+	0x2dab: 0x000c, 0x2dad: 0x000c,
+	0x2db0: 0x000c, 0x2db1: 0x000c, 0x2db2: 0x000c, 0x2db3: 0x000c, 0x2db4: 0x000c, 0x2db5: 0x000c,
+	0x2db7: 0x000c,
+	// Block 0xb7, offset 0x2dc0
+	0x2ddd: 0x000c,
+	0x2dde: 0x000c, 0x2ddf: 0x000c, 0x2de2: 0x000c, 0x2de3: 0x000c,
+	0x2de4: 0x000c, 0x2de5: 0x000c, 0x2de7: 0x000c, 0x2de8: 0x000c, 0x2de9: 0x000c,
+	0x2dea: 0x000c, 0x2deb: 0x000c,
+	// Block 0xb8, offset 0x2e00
+	0x2e30: 0x000c, 0x2e31: 0x000c, 0x2e32: 0x000c, 0x2e33: 0x000c, 0x2e34: 0x000c, 0x2e35: 0x000c,
+	0x2e36: 0x000c, 0x2e38: 0x000c, 0x2e39: 0x000c, 0x2e3a: 0x000c, 0x2e3b: 0x000c,
+	0x2e3c: 0x000c, 0x2e3d: 0x000c,
+	// Block 0xb9, offset 0x2e40
+	0x2e52: 0x000c, 0x2e53: 0x000c, 0x2e54: 0x000c, 0x2e55: 0x000c, 0x2e56: 0x000c, 0x2e57: 0x000c,
+	0x2e58: 0x000c, 0x2e59: 0x000c, 0x2e5a: 0x000c, 0x2e5b: 0x000c, 0x2e5c: 0x000c, 0x2e5d: 0x000c,
+	0x2e5e: 0x000c, 0x2e5f: 0x000c, 0x2e60: 0x000c, 0x2e61: 0x000c, 0x2e62: 0x000c, 0x2e63: 0x000c,
+	0x2e64: 0x000c, 0x2e65: 0x000c, 0x2e66: 0x000c, 0x2e67: 0x000c,
+	0x2e6a: 0x000c, 0x2e6b: 0x000c, 0x2e6c: 0x000c, 0x2e6d: 0x000c, 0x2e6e: 0x000c, 0x2e6f: 0x000c,
+	0x2e70: 0x000c, 0x2e72: 0x000c, 0x2e73: 0x000c, 0x2e75: 0x000c,
+	0x2e76: 0x000c,
+	// Block 0xba, offset 0x2e80
+	0x2eb0: 0x000c, 0x2eb1: 0x000c, 0x2eb2: 0x000c, 0x2eb3: 0x000c, 0x2eb4: 0x000c,
+	// Block 0xbb, offset 0x2ec0
+	0x2ef0: 0x000c, 0x2ef1: 0x000c, 0x2ef2: 0x000c, 0x2ef3: 0x000c, 0x2ef4: 0x000c, 0x2ef5: 0x000c,
+	0x2ef6: 0x000c,
+	// Block 0xbc, offset 0x2f00
+	0x2f0f: 0x000c, 0x2f10: 0x000c, 0x2f11: 0x000c,
+	0x2f12: 0x000c,
+	// Block 0xbd, offset 0x2f40
+	0x2f5d: 0x000c,
+	0x2f5e: 0x000c, 0x2f60: 0x000b, 0x2f61: 0x000b, 0x2f62: 0x000b, 0x2f63: 0x000b,
+	// Block 0xbe, offset 0x2f80
+	0x2fa7: 0x000c, 0x2fa8: 0x000c, 0x2fa9: 0x000c,
+	0x2fb3: 0x000b, 0x2fb4: 0x000b, 0x2fb5: 0x000b,
+	0x2fb6: 0x000b, 0x2fb7: 0x000b, 0x2fb8: 0x000b, 0x2fb9: 0x000b, 0x2fba: 0x000b, 0x2fbb: 0x000c,
+	0x2fbc: 0x000c, 0x2fbd: 0x000c, 0x2fbe: 0x000c, 0x2fbf: 0x000c,
+	// Block 0xbf, offset 0x2fc0
+	0x2fc0: 0x000c, 0x2fc1: 0x000c, 0x2fc2: 0x000c, 0x2fc5: 0x000c,
+	0x2fc6: 0x000c, 0x2fc7: 0x000c, 0x2fc8: 0x000c, 0x2fc9: 0x000c, 0x2fca: 0x000c, 0x2fcb: 0x000c,
+	0x2fea: 0x000c, 0x2feb: 0x000c, 0x2fec: 0x000c, 0x2fed: 0x000c,
+	// Block 0xc0, offset 0x3000
+	0x3000: 0x000a, 0x3001: 0x000a, 0x3002: 0x000c, 0x3003: 0x000c, 0x3004: 0x000c, 0x3005: 0x000a,
+	// Block 0xc1, offset 0x3040
+	0x3040: 0x000a, 0x3041: 0x000a, 0x3042: 0x000a, 0x3043: 0x000a, 0x3044: 0x000a, 0x3045: 0x000a,
+	0x3046: 0x000a, 0x3047: 0x000a, 0x3048: 0x000a, 0x3049: 0x000a, 0x304a: 0x000a, 0x304b: 0x000a,
+	0x304c: 0x000a, 0x304d: 0x000a, 0x304e: 0x000a, 0x304f: 0x000a, 0x3050: 0x000a, 0x3051: 0x000a,
+	0x3052: 0x000a, 0x3053: 0x000a, 0x3054: 0x000a, 0x3055: 0x000a, 0x3056: 0x000a,
+	// Block 0xc2, offset 0x3080
+	0x309b: 0x000a,
+	// Block 0xc3, offset 0x30c0
+	0x30d5: 0x000a,
+	// Block 0xc4, offset 0x3100
+	0x310f: 0x000a,
+	// Block 0xc5, offset 0x3140
+	0x3149: 0x000a,
+	// Block 0xc6, offset 0x3180
+	0x3183: 0x000a,
+	0x318e: 0x0002, 0x318f: 0x0002, 0x3190: 0x0002, 0x3191: 0x0002,
+	0x3192: 0x0002, 0x3193: 0x0002, 0x3194: 0x0002, 0x3195: 0x0002, 0x3196: 0x0002, 0x3197: 0x0002,
+	0x3198: 0x0002, 0x3199: 0x0002, 0x319a: 0x0002, 0x319b: 0x0002, 0x319c: 0x0002, 0x319d: 0x0002,
+	0x319e: 0x0002, 0x319f: 0x0002, 0x31a0: 0x0002, 0x31a1: 0x0002, 0x31a2: 0x0002, 0x31a3: 0x0002,
+	0x31a4: 0x0002, 0x31a5: 0x0002, 0x31a6: 0x0002, 0x31a7: 0x0002, 0x31a8: 0x0002, 0x31a9: 0x0002,
+	0x31aa: 0x0002, 0x31ab: 0x0002, 0x31ac: 0x0002, 0x31ad: 0x0002, 0x31ae: 0x0002, 0x31af: 0x0002,
+	0x31b0: 0x0002, 0x31b1: 0x0002, 0x31b2: 0x0002, 0x31b3: 0x0002, 0x31b4: 0x0002, 0x31b5: 0x0002,
+	0x31b6: 0x0002, 0x31b7: 0x0002, 0x31b8: 0x0002, 0x31b9: 0x0002, 0x31ba: 0x0002, 0x31bb: 0x0002,
+	0x31bc: 0x0002, 0x31bd: 0x0002, 0x31be: 0x0002, 0x31bf: 0x0002,
+	// Block 0xc7, offset 0x31c0
+	0x31c0: 0x000c, 0x31c1: 0x000c, 0x31c2: 0x000c, 0x31c3: 0x000c, 0x31c4: 0x000c, 0x31c5: 0x000c,
+	0x31c6: 0x000c, 0x31c7: 0x000c, 0x31c8: 0x000c, 0x31c9: 0x000c, 0x31ca: 0x000c, 0x31cb: 0x000c,
+	0x31cc: 0x000c, 0x31cd: 0x000c, 0x31ce: 0x000c, 0x31cf: 0x000c, 0x31d0: 0x000c, 0x31d1: 0x000c,
+	0x31d2: 0x000c, 0x31d3: 0x000c, 0x31d4: 0x000c, 0x31d5: 0x000c, 0x31d6: 0x000c, 0x31d7: 0x000c,
+	0x31d8: 0x000c, 0x31d9: 0x000c, 0x31da: 0x000c, 0x31db: 0x000c, 0x31dc: 0x000c, 0x31dd: 0x000c,
+	0x31de: 0x000c, 0x31df: 0x000c, 0x31e0: 0x000c, 0x31e1: 0x000c, 0x31e2: 0x000c, 0x31e3: 0x000c,
+	0x31e4: 0x000c, 0x31e5: 0x000c, 0x31e6: 0x000c, 0x31e7: 0x000c, 0x31e8: 0x000c, 0x31e9: 0x000c,
+	0x31ea: 0x000c, 0x31eb: 0x000c, 0x31ec: 0x000c, 0x31ed: 0x000c, 0x31ee: 0x000c, 0x31ef: 0x000c,
+	0x31f0: 0x000c, 0x31f1: 0x000c, 0x31f2: 0x000c, 0x31f3: 0x000c, 0x31f4: 0x000c, 0x31f5: 0x000c,
+	0x31f6: 0x000c, 0x31fb: 0x000c,
+	0x31fc: 0x000c, 0x31fd: 0x000c, 0x31fe: 0x000c, 0x31ff: 0x000c,
+	// Block 0xc8, offset 0x3200
+	0x3200: 0x000c, 0x3201: 0x000c, 0x3202: 0x000c, 0x3203: 0x000c, 0x3204: 0x000c, 0x3205: 0x000c,
+	0x3206: 0x000c, 0x3207: 0x000c, 0x3208: 0x000c, 0x3209: 0x000c, 0x320a: 0x000c, 0x320b: 0x000c,
+	0x320c: 0x000c, 0x320d: 0x000c, 0x320e: 0x000c, 0x320f: 0x000c, 0x3210: 0x000c, 0x3211: 0x000c,
+	0x3212: 0x000c, 0x3213: 0x000c, 0x3214: 0x000c, 0x3215: 0x000c, 0x3216: 0x000c, 0x3217: 0x000c,
+	0x3218: 0x000c, 0x3219: 0x000c, 0x321a: 0x000c, 0x321b: 0x000c, 0x321c: 0x000c, 0x321d: 0x000c,
+	0x321e: 0x000c, 0x321f: 0x000c, 0x3220: 0x000c, 0x3221: 0x000c, 0x3222: 0x000c, 0x3223: 0x000c,
+	0x3224: 0x000c, 0x3225: 0x000c, 0x3226: 0x000c, 0x3227: 0x000c, 0x3228: 0x000c, 0x3229: 0x000c,
+	0x322a: 0x000c, 0x322b: 0x000c, 0x322c: 0x000c,
+	0x3235: 0x000c,
+	// Block 0xc9, offset 0x3240
+	0x3244: 0x000c,
+	0x325b: 0x000c, 0x325c: 0x000c, 0x325d: 0x000c,
+	0x325e: 0x000c, 0x325f: 0x000c, 0x3261: 0x000c, 0x3262: 0x000c, 0x3263: 0x000c,
+	0x3264: 0x000c, 0x3265: 0x000c, 0x3266: 0x000c, 0x3267: 0x000c, 0x3268: 0x000c, 0x3269: 0x000c,
+	0x326a: 0x000c, 0x326b: 0x000c, 0x326c: 0x000c, 0x326d: 0x000c, 0x326e: 0x000c, 0x326f: 0x000c,
+	// Block 0xca, offset 0x3280
+	0x3280: 0x000c, 0x3281: 0x000c, 0x3282: 0x000c, 0x3283: 0x000c, 0x3284: 0x000c, 0x3285: 0x000c,
+	0x3286: 0x000c, 0x3288: 0x000c, 0x3289: 0x000c, 0x328a: 0x000c, 0x328b: 0x000c,
+	0x328c: 0x000c, 0x328d: 0x000c, 0x328e: 0x000c, 0x328f: 0x000c, 0x3290: 0x000c, 0x3291: 0x000c,
+	0x3292: 0x000c, 0x3293: 0x000c, 0x3294: 0x000c, 0x3295: 0x000c, 0x3296: 0x000c, 0x3297: 0x000c,
+	0x3298: 0x000c, 0x329b: 0x000c, 0x329c: 0x000c, 0x329d: 0x000c,
+	0x329e: 0x000c, 0x329f: 0x000c, 0x32a0: 0x000c, 0x32a1: 0x000c, 0x32a3: 0x000c,
+	0x32a4: 0x000c, 0x32a6: 0x000c, 0x32a7: 0x000c, 0x32a8: 0x000c, 0x32a9: 0x000c,
+	0x32aa: 0x000c,
+	// Block 0xcb, offset 0x32c0
+	0x32c0: 0x0001, 0x32c1: 0x0001, 0x32c2: 0x0001, 0x32c3: 0x0001, 0x32c4: 0x0001, 0x32c5: 0x0001,
+	0x32c6: 0x0001, 0x32c7: 0x0001, 0x32c8: 0x0001, 0x32c9: 0x0001, 0x32ca: 0x0001, 0x32cb: 0x0001,
+	0x32cc: 0x0001, 0x32cd: 0x0001, 0x32ce: 0x0001, 0x32cf: 0x0001, 0x32d0: 0x000c, 0x32d1: 0x000c,
+	0x32d2: 0x000c, 0x32d3: 0x000c, 0x32d4: 0x000c, 0x32d5: 0x000c, 0x32d6: 0x000c, 0x32d7: 0x0001,
+	0x32d8: 0x0001, 0x32d9: 0x0001, 0x32da: 0x0001, 0x32db: 0x0001, 0x32dc: 0x0001, 0x32dd: 0x0001,
+	0x32de: 0x0001, 0x32df: 0x0001, 0x32e0: 0x0001, 0x32e1: 0x0001, 0x32e2: 0x0001, 0x32e3: 0x0001,
+	0x32e4: 0x0001, 0x32e5: 0x0001, 0x32e6: 0x0001, 0x32e7: 0x0001, 0x32e8: 0x0001, 0x32e9: 0x0001,
+	0x32ea: 0x0001, 0x32eb: 0x0001, 0x32ec: 0x0001, 0x32ed: 0x0001, 0x32ee: 0x0001, 0x32ef: 0x0001,
+	0x32f0: 0x0001, 0x32f1: 0x0001, 0x32f2: 0x0001, 0x32f3: 0x0001, 0x32f4: 0x0001, 0x32f5: 0x0001,
+	0x32f6: 0x0001, 0x32f7: 0x0001, 0x32f8: 0x0001, 0x32f9: 0x0001, 0x32fa: 0x0001, 0x32fb: 0x0001,
+	0x32fc: 0x0001, 0x32fd: 0x0001, 0x32fe: 0x0001, 0x32ff: 0x0001,
+	// Block 0xcc, offset 0x3300
+	0x3300: 0x0001, 0x3301: 0x0001, 0x3302: 0x0001, 0x3303: 0x0001, 0x3304: 0x000c, 0x3305: 0x000c,
+	0x3306: 0x000c, 0x3307: 0x000c, 0x3308: 0x000c, 0x3309: 0x000c, 0x330a: 0x000c, 0x330b: 0x0001,
+	0x330c: 0x0001, 0x330d: 0x0001, 0x330e: 0x0001, 0x330f: 0x0001, 0x3310: 0x0001, 0x3311: 0x0001,
+	0x3312: 0x0001, 0x3313: 0x0001, 0x3314: 0x0001, 0x3315: 0x0001, 0x3316: 0x0001, 0x3317: 0x0001,
+	0x3318: 0x0001, 0x3319: 0x0001, 0x331a: 0x0001, 0x331b: 0x0001, 0x331c: 0x0001, 0x331d: 0x0001,
+	0x331e: 0x0001, 0x331f: 0x0001, 0x3320: 0x0001, 0x3321: 0x0001, 0x3322: 0x0001, 0x3323: 0x0001,
+	0x3324: 0x0001, 0x3325: 0x0001, 0x3326: 0x0001, 0x3327: 0x0001, 0x3328: 0x0001, 0x3329: 0x0001,
+	0x332a: 0x0001, 0x332b: 0x0001, 0x332c: 0x0001, 0x332d: 0x0001, 0x332e: 0x0001, 0x332f: 0x0001,
+	0x3330: 0x0001, 0x3331: 0x0001, 0x3332: 0x0001, 0x3333: 0x0001, 0x3334: 0x0001, 0x3335: 0x0001,
+	0x3336: 0x0001, 0x3337: 0x0001, 0x3338: 0x0001, 0x3339: 0x0001, 0x333a: 0x0001, 0x333b: 0x0001,
+	0x333c: 0x0001, 0x333d: 0x0001, 0x333e: 0x0001, 0x333f: 0x0001,
+	// Block 0xcd, offset 0x3340
+	0x3340: 0x000d, 0x3341: 0x000d, 0x3342: 0x000d, 0x3343: 0x000d, 0x3344: 0x000d, 0x3345: 0x000d,
+	0x3346: 0x000d, 0x3347: 0x000d, 0x3348: 0x000d, 0x3349: 0x000d, 0x334a: 0x000d, 0x334b: 0x000d,
+	0x334c: 0x000d, 0x334d: 0x000d, 0x334e: 0x000d, 0x334f: 0x000d, 0x3350: 0x000d, 0x3351: 0x000d,
+	0x3352: 0x000d, 0x3353: 0x000d, 0x3354: 0x000d, 0x3355: 0x000d, 0x3356: 0x000d, 0x3357: 0x000d,
+	0x3358: 0x000d, 0x3359: 0x000d, 0x335a: 0x000d, 0x335b: 0x000d, 0x335c: 0x000d, 0x335d: 0x000d,
+	0x335e: 0x000d, 0x335f: 0x000d, 0x3360: 0x000d, 0x3361: 0x000d, 0x3362: 0x000d, 0x3363: 0x000d,
+	0x3364: 0x000d, 0x3365: 0x000d, 0x3366: 0x000d, 0x3367: 0x000d, 0x3368: 0x000d, 0x3369: 0x000d,
+	0x336a: 0x000d, 0x336b: 0x000d, 0x336c: 0x000d, 0x336d: 0x000d, 0x336e: 0x000d, 0x336f: 0x000d,
+	0x3370: 0x000a, 0x3371: 0x000a, 0x3372: 0x000d, 0x3373: 0x000d, 0x3374: 0x000d, 0x3375: 0x000d,
+	0x3376: 0x000d, 0x3377: 0x000d, 0x3378: 0x000d, 0x3379: 0x000d, 0x337a: 0x000d, 0x337b: 0x000d,
+	0x337c: 0x000d, 0x337d: 0x000d, 0x337e: 0x000d, 0x337f: 0x000d,
+	// Block 0xce, offset 0x3380
+	0x3380: 0x000a, 0x3381: 0x000a, 0x3382: 0x000a, 0x3383: 0x000a, 0x3384: 0x000a, 0x3385: 0x000a,
+	0x3386: 0x000a, 0x3387: 0x000a, 0x3388: 0x000a, 0x3389: 0x000a, 0x338a: 0x000a, 0x338b: 0x000a,
+	0x338c: 0x000a, 0x338d: 0x000a, 0x338e: 0x000a, 0x338f: 0x000a, 0x3390: 0x000a, 0x3391: 0x000a,
+	0x3392: 0x000a, 0x3393: 0x000a, 0x3394: 0x000a, 0x3395: 0x000a, 0x3396: 0x000a, 0x3397: 0x000a,
+	0x3398: 0x000a, 0x3399: 0x000a, 0x339a: 0x000a, 0x339b: 0x000a, 0x339c: 0x000a, 0x339d: 0x000a,
+	0x339e: 0x000a, 0x339f: 0x000a, 0x33a0: 0x000a, 0x33a1: 0x000a, 0x33a2: 0x000a, 0x33a3: 0x000a,
+	0x33a4: 0x000a, 0x33a5: 0x000a, 0x33a6: 0x000a, 0x33a7: 0x000a, 0x33a8: 0x000a, 0x33a9: 0x000a,
+	0x33aa: 0x000a, 0x33ab: 0x000a,
+	0x33b0: 0x000a, 0x33b1: 0x000a, 0x33b2: 0x000a, 0x33b3: 0x000a, 0x33b4: 0x000a, 0x33b5: 0x000a,
+	0x33b6: 0x000a, 0x33b7: 0x000a, 0x33b8: 0x000a, 0x33b9: 0x000a, 0x33ba: 0x000a, 0x33bb: 0x000a,
+	0x33bc: 0x000a, 0x33bd: 0x000a, 0x33be: 0x000a, 0x33bf: 0x000a,
+	// Block 0xcf, offset 0x33c0
+	0x33c0: 0x000a, 0x33c1: 0x000a, 0x33c2: 0x000a, 0x33c3: 0x000a, 0x33c4: 0x000a, 0x33c5: 0x000a,
+	0x33c6: 0x000a, 0x33c7: 0x000a, 0x33c8: 0x000a, 0x33c9: 0x000a, 0x33ca: 0x000a, 0x33cb: 0x000a,
+	0x33cc: 0x000a, 0x33cd: 0x000a, 0x33ce: 0x000a, 0x33cf: 0x000a, 0x33d0: 0x000a, 0x33d1: 0x000a,
+	0x33d2: 0x000a, 0x33d3: 0x000a,
+	0x33e0: 0x000a, 0x33e1: 0x000a, 0x33e2: 0x000a, 0x33e3: 0x000a,
+	0x33e4: 0x000a, 0x33e5: 0x000a, 0x33e6: 0x000a, 0x33e7: 0x000a, 0x33e8: 0x000a, 0x33e9: 0x000a,
+	0x33ea: 0x000a, 0x33eb: 0x000a, 0x33ec: 0x000a, 0x33ed: 0x000a, 0x33ee: 0x000a,
+	0x33f1: 0x000a, 0x33f2: 0x000a, 0x33f3: 0x000a, 0x33f4: 0x000a, 0x33f5: 0x000a,
+	0x33f6: 0x000a, 0x33f7: 0x000a, 0x33f8: 0x000a, 0x33f9: 0x000a, 0x33fa: 0x000a, 0x33fb: 0x000a,
+	0x33fc: 0x000a, 0x33fd: 0x000a, 0x33fe: 0x000a, 0x33ff: 0x000a,
+	// Block 0xd0, offset 0x3400
+	0x3401: 0x000a, 0x3402: 0x000a, 0x3403: 0x000a, 0x3404: 0x000a, 0x3405: 0x000a,
+	0x3406: 0x000a, 0x3407: 0x000a, 0x3408: 0x000a, 0x3409: 0x000a, 0x340a: 0x000a, 0x340b: 0x000a,
+	0x340c: 0x000a, 0x340d: 0x000a, 0x340e: 0x000a, 0x340f: 0x000a, 0x3411: 0x000a,
+	0x3412: 0x000a, 0x3413: 0x000a, 0x3414: 0x000a, 0x3415: 0x000a, 0x3416: 0x000a, 0x3417: 0x000a,
+	0x3418: 0x000a, 0x3419: 0x000a, 0x341a: 0x000a, 0x341b: 0x000a, 0x341c: 0x000a, 0x341d: 0x000a,
+	0x341e: 0x000a, 0x341f: 0x000a, 0x3420: 0x000a, 0x3421: 0x000a, 0x3422: 0x000a, 0x3423: 0x000a,
+	0x3424: 0x000a, 0x3425: 0x000a, 0x3426: 0x000a, 0x3427: 0x000a, 0x3428: 0x000a, 0x3429: 0x000a,
+	0x342a: 0x000a, 0x342b: 0x000a, 0x342c: 0x000a, 0x342d: 0x000a, 0x342e: 0x000a, 0x342f: 0x000a,
+	0x3430: 0x000a, 0x3431: 0x000a, 0x3432: 0x000a, 0x3433: 0x000a, 0x3434: 0x000a, 0x3435: 0x000a,
+	// Block 0xd1, offset 0x3440
+	0x3440: 0x0002, 0x3441: 0x0002, 0x3442: 0x0002, 0x3443: 0x0002, 0x3444: 0x0002, 0x3445: 0x0002,
+	0x3446: 0x0002, 0x3447: 0x0002, 0x3448: 0x0002, 0x3449: 0x0002, 0x344a: 0x0002, 0x344b: 0x000a,
+	0x344c: 0x000a,
+	// Block 0xd2, offset 0x3480
+	0x34aa: 0x000a, 0x34ab: 0x000a,
+	// Block 0xd3, offset 0x34c0
+	0x34c0: 0x000a, 0x34c1: 0x000a, 0x34c2: 0x000a, 0x34c3: 0x000a, 0x34c4: 0x000a, 0x34c5: 0x000a,
+	0x34c6: 0x000a, 0x34c7: 0x000a, 0x34c8: 0x000a, 0x34c9: 0x000a, 0x34ca: 0x000a, 0x34cb: 0x000a,
+	0x34cc: 0x000a, 0x34cd: 0x000a, 0x34ce: 0x000a, 0x34cf: 0x000a, 0x34d0: 0x000a, 0x34d1: 0x000a,
+	0x34d2: 0x000a,
+	0x34e0: 0x000a, 0x34e1: 0x000a, 0x34e2: 0x000a, 0x34e3: 0x000a,
+	0x34e4: 0x000a, 0x34e5: 0x000a, 0x34e6: 0x000a, 0x34e7: 0x000a, 0x34e8: 0x000a, 0x34e9: 0x000a,
+	0x34ea: 0x000a, 0x34eb: 0x000a, 0x34ec: 0x000a,
+	0x34f0: 0x000a, 0x34f1: 0x000a, 0x34f2: 0x000a, 0x34f3: 0x000a, 0x34f4: 0x000a, 0x34f5: 0x000a,
+	0x34f6: 0x000a,
+	// Block 0xd4, offset 0x3500
+	0x3500: 0x000a, 0x3501: 0x000a, 0x3502: 0x000a, 0x3503: 0x000a, 0x3504: 0x000a, 0x3505: 0x000a,
+	0x3506: 0x000a, 0x3507: 0x000a, 0x3508: 0x000a, 0x3509: 0x000a, 0x350a: 0x000a, 0x350b: 0x000a,
+	0x350c: 0x000a, 0x350d: 0x000a, 0x350e: 0x000a, 0x350f: 0x000a, 0x3510: 0x000a, 0x3511: 0x000a,
+	0x3512: 0x000a, 0x3513: 0x000a, 0x3514: 0x000a,
+	// Block 0xd5, offset 0x3540
+	0x3540: 0x000a, 0x3541: 0x000a, 0x3542: 0x000a, 0x3543: 0x000a, 0x3544: 0x000a, 0x3545: 0x000a,
+	0x3546: 0x000a, 0x3547: 0x000a, 0x3548: 0x000a, 0x3549: 0x000a, 0x354a: 0x000a, 0x354b: 0x000a,
+	0x3550: 0x000a, 0x3551: 0x000a,
+	0x3552: 0x000a, 0x3553: 0x000a, 0x3554: 0x000a, 0x3555: 0x000a, 0x3556: 0x000a, 0x3557: 0x000a,
+	0x3558: 0x000a, 0x3559: 0x000a, 0x355a: 0x000a, 0x355b: 0x000a, 0x355c: 0x000a, 0x355d: 0x000a,
+	0x355e: 0x000a, 0x355f: 0x000a, 0x3560: 0x000a, 0x3561: 0x000a, 0x3562: 0x000a, 0x3563: 0x000a,
+	0x3564: 0x000a, 0x3565: 0x000a, 0x3566: 0x000a, 0x3567: 0x000a, 0x3568: 0x000a, 0x3569: 0x000a,
+	0x356a: 0x000a, 0x356b: 0x000a, 0x356c: 0x000a, 0x356d: 0x000a, 0x356e: 0x000a, 0x356f: 0x000a,
+	0x3570: 0x000a, 0x3571: 0x000a, 0x3572: 0x000a, 0x3573: 0x000a, 0x3574: 0x000a, 0x3575: 0x000a,
+	0x3576: 0x000a, 0x3577: 0x000a, 0x3578: 0x000a, 0x3579: 0x000a, 0x357a: 0x000a, 0x357b: 0x000a,
+	0x357c: 0x000a, 0x357d: 0x000a, 0x357e: 0x000a, 0x357f: 0x000a,
+	// Block 0xd6, offset 0x3580
+	0x3580: 0x000a, 0x3581: 0x000a, 0x3582: 0x000a, 0x3583: 0x000a, 0x3584: 0x000a, 0x3585: 0x000a,
+	0x3586: 0x000a, 0x3587: 0x000a,
+	0x3590: 0x000a, 0x3591: 0x000a,
+	0x3592: 0x000a, 0x3593: 0x000a, 0x3594: 0x000a, 0x3595: 0x000a, 0x3596: 0x000a, 0x3597: 0x000a,
+	0x3598: 0x000a, 0x3599: 0x000a,
+	0x35a0: 0x000a, 0x35a1: 0x000a, 0x35a2: 0x000a, 0x35a3: 0x000a,
+	0x35a4: 0x000a, 0x35a5: 0x000a, 0x35a6: 0x000a, 0x35a7: 0x000a, 0x35a8: 0x000a, 0x35a9: 0x000a,
+	0x35aa: 0x000a, 0x35ab: 0x000a, 0x35ac: 0x000a, 0x35ad: 0x000a, 0x35ae: 0x000a, 0x35af: 0x000a,
+	0x35b0: 0x000a, 0x35b1: 0x000a, 0x35b2: 0x000a, 0x35b3: 0x000a, 0x35b4: 0x000a, 0x35b5: 0x000a,
+	0x35b6: 0x000a, 0x35b7: 0x000a, 0x35b8: 0x000a, 0x35b9: 0x000a, 0x35ba: 0x000a, 0x35bb: 0x000a,
+	0x35bc: 0x000a, 0x35bd: 0x000a, 0x35be: 0x000a, 0x35bf: 0x000a,
+	// Block 0xd7, offset 0x35c0
+	0x35c0: 0x000a, 0x35c1: 0x000a, 0x35c2: 0x000a, 0x35c3: 0x000a, 0x35c4: 0x000a, 0x35c5: 0x000a,
+	0x35c6: 0x000a, 0x35c7: 0x000a,
+	0x35d0: 0x000a, 0x35d1: 0x000a,
+	0x35d2: 0x000a, 0x35d3: 0x000a, 0x35d4: 0x000a, 0x35d5: 0x000a, 0x35d6: 0x000a, 0x35d7: 0x000a,
+	0x35d8: 0x000a, 0x35d9: 0x000a, 0x35da: 0x000a, 0x35db: 0x000a, 0x35dc: 0x000a, 0x35dd: 0x000a,
+	0x35de: 0x000a, 0x35df: 0x000a, 0x35e0: 0x000a, 0x35e1: 0x000a, 0x35e2: 0x000a, 0x35e3: 0x000a,
+	0x35e4: 0x000a, 0x35e5: 0x000a, 0x35e6: 0x000a, 0x35e7: 0x000a, 0x35e8: 0x000a, 0x35e9: 0x000a,
+	0x35ea: 0x000a, 0x35eb: 0x000a, 0x35ec: 0x000a, 0x35ed: 0x000a,
+	// Block 0xd8, offset 0x3600
+	0x3610: 0x000a, 0x3611: 0x000a,
+	0x3612: 0x000a, 0x3613: 0x000a, 0x3614: 0x000a, 0x3615: 0x000a, 0x3616: 0x000a, 0x3617: 0x000a,
+	0x3618: 0x000a, 0x3619: 0x000a, 0x361a: 0x000a, 0x361b: 0x000a, 0x361c: 0x000a, 0x361d: 0x000a,
+	0x361e: 0x000a, 0x3620: 0x000a, 0x3621: 0x000a, 0x3622: 0x000a, 0x3623: 0x000a,
+	0x3624: 0x000a, 0x3625: 0x000a, 0x3626: 0x000a, 0x3627: 0x000a,
+	0x3630: 0x000a, 0x3633: 0x000a, 0x3634: 0x000a, 0x3635: 0x000a,
+	0x3636: 0x000a, 0x3637: 0x000a, 0x3638: 0x000a, 0x3639: 0x000a, 0x363a: 0x000a, 0x363b: 0x000a,
+	0x363c: 0x000a, 0x363d: 0x000a, 0x363e: 0x000a,
+	// Block 0xd9, offset 0x3640
+	0x3640: 0x000a, 0x3641: 0x000a, 0x3642: 0x000a, 0x3643: 0x000a, 0x3644: 0x000a, 0x3645: 0x000a,
+	0x3646: 0x000a, 0x3647: 0x000a, 0x3648: 0x000a, 0x3649: 0x000a, 0x364a: 0x000a, 0x364b: 0x000a,
+	0x3650: 0x000a, 0x3651: 0x000a,
+	0x3652: 0x000a, 0x3653: 0x000a, 0x3654: 0x000a, 0x3655: 0x000a, 0x3656: 0x000a, 0x3657: 0x000a,
+	0x3658: 0x000a, 0x3659: 0x000a, 0x365a: 0x000a, 0x365b: 0x000a, 0x365c: 0x000a, 0x365d: 0x000a,
+	0x365e: 0x000a,
+	// Block 0xda, offset 0x3680
+	0x3680: 0x000a, 0x3681: 0x000a, 0x3682: 0x000a, 0x3683: 0x000a, 0x3684: 0x000a, 0x3685: 0x000a,
+	0x3686: 0x000a, 0x3687: 0x000a, 0x3688: 0x000a, 0x3689: 0x000a, 0x368a: 0x000a, 0x368b: 0x000a,
+	0x368c: 0x000a, 0x368d: 0x000a, 0x368e: 0x000a, 0x368f: 0x000a, 0x3690: 0x000a, 0x3691: 0x000a,
+	// Block 0xdb, offset 0x36c0
+	0x36fe: 0x000b, 0x36ff: 0x000b,
+	// Block 0xdc, offset 0x3700
+	0x3700: 0x000b, 0x3701: 0x000b, 0x3702: 0x000b, 0x3703: 0x000b, 0x3704: 0x000b, 0x3705: 0x000b,
+	0x3706: 0x000b, 0x3707: 0x000b, 0x3708: 0x000b, 0x3709: 0x000b, 0x370a: 0x000b, 0x370b: 0x000b,
+	0x370c: 0x000b, 0x370d: 0x000b, 0x370e: 0x000b, 0x370f: 0x000b, 0x3710: 0x000b, 0x3711: 0x000b,
+	0x3712: 0x000b, 0x3713: 0x000b, 0x3714: 0x000b, 0x3715: 0x000b, 0x3716: 0x000b, 0x3717: 0x000b,
+	0x3718: 0x000b, 0x3719: 0x000b, 0x371a: 0x000b, 0x371b: 0x000b, 0x371c: 0x000b, 0x371d: 0x000b,
+	0x371e: 0x000b, 0x371f: 0x000b, 0x3720: 0x000b, 0x3721: 0x000b, 0x3722: 0x000b, 0x3723: 0x000b,
+	0x3724: 0x000b, 0x3725: 0x000b, 0x3726: 0x000b, 0x3727: 0x000b, 0x3728: 0x000b, 0x3729: 0x000b,
+	0x372a: 0x000b, 0x372b: 0x000b, 0x372c: 0x000b, 0x372d: 0x000b, 0x372e: 0x000b, 0x372f: 0x000b,
+	0x3730: 0x000b, 0x3731: 0x000b, 0x3732: 0x000b, 0x3733: 0x000b, 0x3734: 0x000b, 0x3735: 0x000b,
+	0x3736: 0x000b, 0x3737: 0x000b, 0x3738: 0x000b, 0x3739: 0x000b, 0x373a: 0x000b, 0x373b: 0x000b,
+	0x373c: 0x000b, 0x373d: 0x000b, 0x373e: 0x000b, 0x373f: 0x000b,
+	// Block 0xdd, offset 0x3740
+	0x3740: 0x000c, 0x3741: 0x000c, 0x3742: 0x000c, 0x3743: 0x000c, 0x3744: 0x000c, 0x3745: 0x000c,
+	0x3746: 0x000c, 0x3747: 0x000c, 0x3748: 0x000c, 0x3749: 0x000c, 0x374a: 0x000c, 0x374b: 0x000c,
+	0x374c: 0x000c, 0x374d: 0x000c, 0x374e: 0x000c, 0x374f: 0x000c, 0x3750: 0x000c, 0x3751: 0x000c,
+	0x3752: 0x000c, 0x3753: 0x000c, 0x3754: 0x000c, 0x3755: 0x000c, 0x3756: 0x000c, 0x3757: 0x000c,
+	0x3758: 0x000c, 0x3759: 0x000c, 0x375a: 0x000c, 0x375b: 0x000c, 0x375c: 0x000c, 0x375d: 0x000c,
+	0x375e: 0x000c, 0x375f: 0x000c, 0x3760: 0x000c, 0x3761: 0x000c, 0x3762: 0x000c, 0x3763: 0x000c,
+	0x3764: 0x000c, 0x3765: 0x000c, 0x3766: 0x000c, 0x3767: 0x000c, 0x3768: 0x000c, 0x3769: 0x000c,
+	0x376a: 0x000c, 0x376b: 0x000c, 0x376c: 0x000c, 0x376d: 0x000c, 0x376e: 0x000c, 0x376f: 0x000c,
+	0x3770: 0x000b, 0x3771: 0x000b, 0x3772: 0x000b, 0x3773: 0x000b, 0x3774: 0x000b, 0x3775: 0x000b,
+	0x3776: 0x000b, 0x3777: 0x000b, 0x3778: 0x000b, 0x3779: 0x000b, 0x377a: 0x000b, 0x377b: 0x000b,
+	0x377c: 0x000b, 0x377d: 0x000b, 0x377e: 0x000b, 0x377f: 0x000b,
+}
+
+// bidiIndex: 24 blocks, 1536 entries, 1536 bytes
+// Block 0 is the zero block.
+var bidiIndex = [1536]uint8{
+	// Block 0x0, offset 0x0
+	// Block 0x1, offset 0x40
+	// Block 0x2, offset 0x80
+	// Block 0x3, offset 0xc0
+	0xc2: 0x01, 0xc3: 0x02,
+	0xca: 0x03, 0xcb: 0x04, 0xcc: 0x05, 0xcd: 0x06, 0xce: 0x07, 0xcf: 0x08,
+	0xd2: 0x09, 0xd6: 0x0a, 0xd7: 0x0b,
+	0xd8: 0x0c, 0xd9: 0x0d, 0xda: 0x0e, 0xdb: 0x0f, 0xdc: 0x10, 0xdd: 0x11, 0xde: 0x12, 0xdf: 0x13,
+	0xe0: 0x02, 0xe1: 0x03, 0xe2: 0x04, 0xe3: 0x05, 0xe4: 0x06,
+	0xea: 0x07, 0xef: 0x08,
+	0xf0: 0x11, 0xf1: 0x12, 0xf2: 0x12, 0xf3: 0x14, 0xf4: 0x15,
+	// Block 0x4, offset 0x100
+	0x120: 0x14, 0x121: 0x15, 0x122: 0x16, 0x123: 0x17, 0x124: 0x18, 0x125: 0x19, 0x126: 0x1a, 0x127: 0x1b,
+	0x128: 0x1c, 0x129: 0x1d, 0x12a: 0x1c, 0x12b: 0x1e, 0x12c: 0x1f, 0x12d: 0x20, 0x12e: 0x21, 0x12f: 0x22,
+	0x130: 0x23, 0x131: 0x24, 0x132: 0x1a, 0x133: 0x25, 0x134: 0x26, 0x135: 0x27, 0x137: 0x28,
+	0x138: 0x29, 0x139: 0x2a, 0x13a: 0x2b, 0x13b: 0x2c, 0x13c: 0x2d, 0x13d: 0x2e, 0x13e: 0x2f, 0x13f: 0x30,
+	// Block 0x5, offset 0x140
+	0x140: 0x31, 0x141: 0x32, 0x142: 0x33,
+	0x14d: 0x34, 0x14e: 0x35,
+	0x150: 0x36,
+	0x15a: 0x37, 0x15c: 0x38, 0x15d: 0x39, 0x15e: 0x3a, 0x15f: 0x3b,
+	0x160: 0x3c, 0x162: 0x3d, 0x164: 0x3e, 0x165: 0x3f, 0x167: 0x40,
+	0x168: 0x41, 0x169: 0x42, 0x16a: 0x43, 0x16c: 0x44, 0x16d: 0x45, 0x16e: 0x46, 0x16f: 0x47,
+	0x170: 0x48, 0x173: 0x49, 0x177: 0x4a,
+	0x17e: 0x4b, 0x17f: 0x4c,
+	// Block 0x6, offset 0x180
+	0x180: 0x4d, 0x181: 0x4e, 0x182: 0x4f, 0x183: 0x50, 0x184: 0x51, 0x185: 0x52, 0x186: 0x53, 0x187: 0x54,
+	0x188: 0x55, 0x189: 0x54, 0x18a: 0x54, 0x18b: 0x54, 0x18c: 0x56, 0x18d: 0x57, 0x18e: 0x58, 0x18f: 0x59,
+	0x190: 0x5a, 0x191: 0x5b, 0x192: 0x5c, 0x193: 0x5d, 0x194: 0x54, 0x195: 0x54, 0x196: 0x54, 0x197: 0x54,
+	0x198: 0x54, 0x199: 0x54, 0x19a: 0x5e, 0x19b: 0x54, 0x19c: 0x54, 0x19d: 0x5f, 0x19e: 0x54, 0x19f: 0x60,
+	0x1a4: 0x54, 0x1a5: 0x54, 0x1a6: 0x61, 0x1a7: 0x62,
+	0x1a8: 0x54, 0x1a9: 0x54, 0x1aa: 0x54, 0x1ab: 0x54, 0x1ac: 0x54, 0x1ad: 0x63, 0x1ae: 0x64, 0x1af: 0x65,
+	0x1b3: 0x66, 0x1b5: 0x67, 0x1b7: 0x68,
+	0x1b8: 0x69, 0x1b9: 0x6a, 0x1ba: 0x6b, 0x1bb: 0x6c, 0x1bc: 0x54, 0x1bd: 0x54, 0x1be: 0x54, 0x1bf: 0x6d,
+	// Block 0x7, offset 0x1c0
+	0x1c0: 0x6e, 0x1c2: 0x6f, 0x1c3: 0x70, 0x1c7: 0x71,
+	0x1c8: 0x72, 0x1c9: 0x73, 0x1ca: 0x74, 0x1cb: 0x75, 0x1cd: 0x76, 0x1cf: 0x77,
+	// Block 0x8, offset 0x200
+	0x237: 0x54,
+	// Block 0x9, offset 0x240
+	0x252: 0x78, 0x253: 0x79,
+	0x258: 0x7a, 0x259: 0x7b, 0x25a: 0x7c, 0x25b: 0x7d, 0x25c: 0x7e, 0x25e: 0x7f,
+	0x260: 0x80, 0x261: 0x81, 0x263: 0x82, 0x264: 0x83, 0x265: 0x84, 0x266: 0x85, 0x267: 0x86,
+	0x268: 0x87, 0x269: 0x88, 0x26a: 0x89, 0x26b: 0x8a, 0x26f: 0x8b,
+	// Block 0xa, offset 0x280
+	0x2ac: 0x8c, 0x2ad: 0x8d, 0x2ae: 0x0e, 0x2af: 0x0e,
+	0x2b0: 0x0e, 0x2b1: 0x0e, 0x2b2: 0x0e, 0x2b3: 0x0e, 0x2b4: 0x8e, 0x2b5: 0x0e, 0x2b6: 0x0e, 0x2b7: 0x8f,
+	0x2b8: 0x90, 0x2b9: 0x91, 0x2ba: 0x0e, 0x2bb: 0x92, 0x2bc: 0x93, 0x2bd: 0x94, 0x2bf: 0x95,
+	// Block 0xb, offset 0x2c0
+	0x2c4: 0x96, 0x2c5: 0x54, 0x2c6: 0x97, 0x2c7: 0x98,
+	0x2cb: 0x99, 0x2cd: 0x9a,
+	0x2e0: 0x9b, 0x2e1: 0x9b, 0x2e2: 0x9b, 0x2e3: 0x9b, 0x2e4: 0x9c, 0x2e5: 0x9b, 0x2e6: 0x9b, 0x2e7: 0x9b,
+	0x2e8: 0x9d, 0x2e9: 0x9b, 0x2ea: 0x9b, 0x2eb: 0x9e, 0x2ec: 0x9f, 0x2ed: 0x9b, 0x2ee: 0x9b, 0x2ef: 0x9b,
+	0x2f0: 0x9b, 0x2f1: 0x9b, 0x2f2: 0x9b, 0x2f3: 0x9b, 0x2f4: 0x9b, 0x2f5: 0x9b, 0x2f6: 0x9b, 0x2f7: 0x9b,
+	0x2f8: 0x9b, 0x2f9: 0xa0, 0x2fa: 0x9b, 0x2fb: 0x9b, 0x2fc: 0x9b, 0x2fd: 0x9b, 0x2fe: 0x9b, 0x2ff: 0x9b,
+	// Block 0xc, offset 0x300
+	0x300: 0xa1, 0x301: 0xa2, 0x302: 0xa3, 0x304: 0xa4, 0x305: 0xa5, 0x306: 0xa6, 0x307: 0xa7,
+	0x308: 0xa8, 0x30b: 0xa9, 0x30c: 0xaa, 0x30d: 0xab,
+	0x310: 0xac, 0x311: 0xad, 0x312: 0xae, 0x313: 0xaf, 0x316: 0xb0, 0x317: 0xb1,
+	0x318: 0xb2, 0x319: 0xb3, 0x31a: 0xb4, 0x31c: 0xb5,
+	0x330: 0xb6, 0x332: 0xb7,
+	// Block 0xd, offset 0x340
+	0x36b: 0xb8, 0x36c: 0xb9,
+	0x37e: 0xba,
+	// Block 0xe, offset 0x380
+	0x3b2: 0xbb,
+	// Block 0xf, offset 0x3c0
+	0x3c5: 0xbc, 0x3c6: 0xbd,
+	0x3c8: 0x54, 0x3c9: 0xbe, 0x3cc: 0x54, 0x3cd: 0xbf,
+	0x3db: 0xc0, 0x3dc: 0xc1, 0x3dd: 0xc2, 0x3de: 0xc3, 0x3df: 0xc4,
+	0x3e8: 0xc5, 0x3e9: 0xc6, 0x3ea: 0xc7,
+	// Block 0x10, offset 0x400
+	0x400: 0xc8,
+	0x420: 0x9b, 0x421: 0x9b, 0x422: 0x9b, 0x423: 0xc9, 0x424: 0x9b, 0x425: 0xca, 0x426: 0x9b, 0x427: 0x9b,
+	0x428: 0x9b, 0x429: 0x9b, 0x42a: 0x9b, 0x42b: 0x9b, 0x42c: 0x9b, 0x42d: 0x9b, 0x42e: 0x9b, 0x42f: 0x9b,
+	0x430: 0x9b, 0x431: 0x9b, 0x432: 0x9b, 0x433: 0x9b, 0x434: 0x9b, 0x435: 0x9b, 0x436: 0x9b, 0x437: 0x9b,
+	0x438: 0x0e, 0x439: 0x0e, 0x43a: 0x0e, 0x43b: 0xcb, 0x43c: 0x9b, 0x43d: 0x9b, 0x43e: 0x9b, 0x43f: 0x9b,
+	// Block 0x11, offset 0x440
+	0x440: 0xcc, 0x441: 0x54, 0x442: 0xcd, 0x443: 0xce, 0x444: 0xcf, 0x445: 0xd0,
+	0x44c: 0x54, 0x44d: 0x54, 0x44e: 0x54, 0x44f: 0x54,
+	0x450: 0x54, 0x451: 0x54, 0x452: 0x54, 0x453: 0x54, 0x454: 0x54, 0x455: 0x54, 0x456: 0x54, 0x457: 0x54,
+	0x458: 0x54, 0x459: 0x54, 0x45a: 0x54, 0x45b: 0xd1, 0x45c: 0x54, 0x45d: 0x6c, 0x45e: 0x54, 0x45f: 0xd2,
+	0x460: 0xd3, 0x461: 0xd4, 0x462: 0xd5, 0x464: 0xd6, 0x465: 0xd7, 0x466: 0xd8, 0x467: 0x36,
+	0x47f: 0xd9,
+	// Block 0x12, offset 0x480
+	0x4bf: 0xd9,
+	// Block 0x13, offset 0x4c0
+	0x4d0: 0x09, 0x4d1: 0x0a, 0x4d6: 0x0b,
+	0x4db: 0x0c, 0x4dd: 0x0d, 0x4de: 0x0e, 0x4df: 0x0f,
+	0x4ef: 0x10,
+	0x4ff: 0x10,
+	// Block 0x14, offset 0x500
+	0x50f: 0x10,
+	0x51f: 0x10,
+	0x52f: 0x10,
+	0x53f: 0x10,
+	// Block 0x15, offset 0x540
+	0x540: 0xda, 0x541: 0xda, 0x542: 0xda, 0x543: 0xda, 0x544: 0x05, 0x545: 0x05, 0x546: 0x05, 0x547: 0xdb,
+	0x548: 0xda, 0x549: 0xda, 0x54a: 0xda, 0x54b: 0xda, 0x54c: 0xda, 0x54d: 0xda, 0x54e: 0xda, 0x54f: 0xda,
+	0x550: 0xda, 0x551: 0xda, 0x552: 0xda, 0x553: 0xda, 0x554: 0xda, 0x555: 0xda, 0x556: 0xda, 0x557: 0xda,
+	0x558: 0xda, 0x559: 0xda, 0x55a: 0xda, 0x55b: 0xda, 0x55c: 0xda, 0x55d: 0xda, 0x55e: 0xda, 0x55f: 0xda,
+	0x560: 0xda, 0x561: 0xda, 0x562: 0xda, 0x563: 0xda, 0x564: 0xda, 0x565: 0xda, 0x566: 0xda, 0x567: 0xda,
+	0x568: 0xda, 0x569: 0xda, 0x56a: 0xda, 0x56b: 0xda, 0x56c: 0xda, 0x56d: 0xda, 0x56e: 0xda, 0x56f: 0xda,
+	0x570: 0xda, 0x571: 0xda, 0x572: 0xda, 0x573: 0xda, 0x574: 0xda, 0x575: 0xda, 0x576: 0xda, 0x577: 0xda,
+	0x578: 0xda, 0x579: 0xda, 0x57a: 0xda, 0x57b: 0xda, 0x57c: 0xda, 0x57d: 0xda, 0x57e: 0xda, 0x57f: 0xda,
+	// Block 0x16, offset 0x580
+	0x58f: 0x10,
+	0x59f: 0x10,
+	0x5a0: 0x13,
+	0x5af: 0x10,
+	0x5bf: 0x10,
+	// Block 0x17, offset 0x5c0
+	0x5cf: 0x10,
+}
+
+// Total table size 15800 bytes (15KiB); checksum: F50EF68C
diff --git a/libgo/go/golang_org/x/text/unicode/bidi/trieval.go b/libgo/go/golang_org/x/text/unicode/bidi/trieval.go
new file mode 100644
index 0000000..a825fde
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/bidi/trieval.go
@@ -0,0 +1,62 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Code generated by running "go generate" in golang_org/x/text. DO NOT EDIT.
+
+package bidi
+
+// Class is the Unicode BiDi class. Each rune has a single class.
+type Class uint
+
+const (
+	L       Class = iota // LeftToRight
+	R                    // RightToLeft
+	EN                   // EuropeanNumber
+	ES                   // EuropeanSeparator
+	ET                   // EuropeanTerminator
+	AN                   // ArabicNumber
+	CS                   // CommonSeparator
+	B                    // ParagraphSeparator
+	S                    // SegmentSeparator
+	WS                   // WhiteSpace
+	ON                   // OtherNeutral
+	BN                   // BoundaryNeutral
+	NSM                  // NonspacingMark
+	AL                   // ArabicLetter
+	Control              // Control LRO - PDI
+
+	numClass
+
+	LRO // LeftToRightOverride
+	RLO // RightToLeftOverride
+	LRE // LeftToRightEmbedding
+	RLE // RightToLeftEmbedding
+	PDF // PopDirectionalFormat
+	LRI // LeftToRightIsolate
+	RLI // RightToLeftIsolate
+	FSI // FirstStrongIsolate
+	PDI // PopDirectionalIsolate
+
+	unknownClass = ^Class(0)
+)
+
+var controlToClass = map[rune]Class{
+	0x202D: LRO, // LeftToRightOverride,
+	0x202E: RLO, // RightToLeftOverride,
+	0x202A: LRE, // LeftToRightEmbedding,
+	0x202B: RLE, // RightToLeftEmbedding,
+	0x202C: PDF, // PopDirectionalFormat,
+	0x2066: LRI, // LeftToRightIsolate,
+	0x2067: RLI, // RightToLeftIsolate,
+	0x2068: FSI, // FirstStrongIsolate,
+	0x2069: PDI, // PopDirectionalIsolate,
+}
+
+// A trie entry has the following bits:
+// 7..5  XOR mask for brackets
+// 4     1: Bracket open, 0: Bracket close
+// 3..0  Class type
+
+const (
+	openMask     = 0x10
+	xorMaskShift = 5
+)
diff --git a/libgo/go/golang_org/x/text/unicode/doc.go b/libgo/go/golang_org/x/text/unicode/doc.go
new file mode 100644
index 0000000..36b462a
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/doc.go
@@ -0,0 +1,10 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// unicode holds packages with implementations of Unicode standards that are
+// mostly used as building blocks for other packages in golang_org/x/text,
+// layout engines, or are otherwise more low-level in nature.
+package unicode
diff --git a/libgo/go/golang_org/x/text/unicode/norm/composition.go b/libgo/go/golang_org/x/text/unicode/norm/composition.go
index d17b278..7380b05 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/composition.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/composition.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
diff --git a/libgo/go/golang_org/x/text/unicode/norm/example_iter_test.go b/libgo/go/golang_org/x/text/unicode/norm/example_iter_test.go
new file mode 100644
index 0000000..aed6c16
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/norm/example_iter_test.go
@@ -0,0 +1,84 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm_test
+
+import (
+	"bytes"
+	"fmt"
+	"unicode/utf8"
+
+	"golang_org/x/text/unicode/norm"
+)
+
+// EqualSimple uses a norm.Iter to compare two non-normalized
+// strings for equivalence.
+func EqualSimple(a, b string) bool {
+	var ia, ib norm.Iter
+	ia.InitString(norm.NFKD, a)
+	ib.InitString(norm.NFKD, b)
+	for !ia.Done() && !ib.Done() {
+		if !bytes.Equal(ia.Next(), ib.Next()) {
+			return false
+		}
+	}
+	return ia.Done() && ib.Done()
+}
+
+// FindPrefix finds the longest common prefix of ASCII characters
+// of a and b.
+func FindPrefix(a, b string) int {
+	i := 0
+	for ; i < len(a) && i < len(b) && a[i] < utf8.RuneSelf && a[i] == b[i]; i++ {
+	}
+	return i
+}
+
+// EqualOpt is like EqualSimple, but optimizes the special
+// case for ASCII characters.
+func EqualOpt(a, b string) bool {
+	n := FindPrefix(a, b)
+	a, b = a[n:], b[n:]
+	var ia, ib norm.Iter
+	ia.InitString(norm.NFKD, a)
+	ib.InitString(norm.NFKD, b)
+	for !ia.Done() && !ib.Done() {
+		if !bytes.Equal(ia.Next(), ib.Next()) {
+			return false
+		}
+		if n := int64(FindPrefix(a[ia.Pos():], b[ib.Pos():])); n != 0 {
+			ia.Seek(n, 1)
+			ib.Seek(n, 1)
+		}
+	}
+	return ia.Done() && ib.Done()
+}
+
+var compareTests = []struct{ a, b string }{
+	{"aaa", "aaa"},
+	{"aaa", "aab"},
+	{"a\u0300a", "\u00E0a"},
+	{"a\u0300\u0320b", "a\u0320\u0300b"},
+	{"\u1E0A\u0323", "\x44\u0323\u0307"},
+	// A character that decomposes into multiple segments
+	// spans several iterations.
+	{"\u3304", "\u30A4\u30CB\u30F3\u30AF\u3099"},
+}
+
+func ExampleIter() {
+	for i, t := range compareTests {
+		r0 := EqualSimple(t.a, t.b)
+		r1 := EqualOpt(t.a, t.b)
+		fmt.Printf("%d: %v %v\n", i, r0, r1)
+	}
+	// Output:
+	// 0: true true
+	// 1: false false
+	// 2: true true
+	// 3: true true
+	// 4: true true
+	// 5: true true
+}
diff --git a/libgo/go/golang_org/x/text/unicode/norm/example_test.go b/libgo/go/golang_org/x/text/unicode/norm/example_test.go
new file mode 100644
index 0000000..72e72c9
--- /dev/null
+++ b/libgo/go/golang_org/x/text/unicode/norm/example_test.go
@@ -0,0 +1,29 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm_test
+
+import (
+	"fmt"
+
+	"golang_org/x/text/unicode/norm"
+)
+
+func ExampleForm_NextBoundary() {
+	s := norm.NFD.String("Mêlée")
+
+	for i := 0; i < len(s); {
+		d := norm.NFC.NextBoundaryInString(s[i:], true)
+		fmt.Printf("%[1]s: %+[1]q\n", s[i:i+d])
+		i += d
+	}
+	// Output:
+	// M: "M"
+	// ê: "e\u0302"
+	// l: "l"
+	// é: "e\u0301"
+	// e: "e"
+}
diff --git a/libgo/go/golang_org/x/text/unicode/norm/forminfo.go b/libgo/go/golang_org/x/text/unicode/norm/forminfo.go
index 15a67c6..f3e2930 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/forminfo.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/forminfo.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
@@ -10,7 +12,7 @@
 // and its corresponding decomposing form share the same trie.  Each trie maps
 // a rune to a uint16. The values take two forms.  For v >= 0x8000:
 //   bits
-//   15:    1 (inverse of NFD_QD bit of qcInfo)
+//   15:    1 (inverse of NFD_QC bit of qcInfo)
 //   13..7: qcInfo (see below). isYesD is always true (no decompostion).
 //    6..0: ccc (compressed CCC value).
 // For v < 0x8000, the respective rune has a decomposition and v is an index
@@ -56,28 +58,31 @@
 	nextMain                 iterFunc
 }
 
-var formTable []*formInfo
-
-func init() {
-	formTable = make([]*formInfo, 4)
-
-	for i := range formTable {
-		f := &formInfo{}
-		formTable[i] = f
-		f.form = Form(i)
-		if Form(i) == NFKD || Form(i) == NFKC {
-			f.compatibility = true
-			f.info = lookupInfoNFKC
-		} else {
-			f.info = lookupInfoNFC
-		}
-		f.nextMain = nextDecomposed
-		if Form(i) == NFC || Form(i) == NFKC {
-			f.nextMain = nextComposed
-			f.composing = true
-		}
-	}
-}
+var formTable = []*formInfo{{
+	form:          NFC,
+	composing:     true,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFD,
+	composing:     false,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextDecomposed,
+}, {
+	form:          NFKC,
+	composing:     true,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFKD,
+	composing:     false,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextDecomposed,
+}}
 
 // We do not distinguish between boundaries for NFC, NFD, etc. to avoid
 // unexpected behavior for the user.  For example, in NFD, there is a boundary
diff --git a/libgo/go/golang_org/x/text/unicode/norm/input.go b/libgo/go/golang_org/x/text/unicode/norm/input.go
index 045d4cc..202bde1 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/input.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/input.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
diff --git a/libgo/go/golang_org/x/text/unicode/norm/iter.go b/libgo/go/golang_org/x/text/unicode/norm/iter.go
index 0a42a72..c0cf949 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/iter.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/iter.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
diff --git a/libgo/go/golang_org/x/text/unicode/norm/normalize.go b/libgo/go/golang_org/x/text/unicode/norm/normalize.go
index 15c962e..4427ee3 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/normalize.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/normalize.go
@@ -1,12 +1,13 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:generate go run maketables.go triegen.go
-//go:generate go run maketables.go triegen.go -test
+// Note: the file data_test.go that is generated should not be checked in.
 
 // Package norm contains types and functions for normalizing Unicode strings.
-package norm // import "golang.org/x/text/unicode/norm"
+package norm // import "golang_org/x/text/unicode/norm"
 
 import (
 	"unicode/utf8"
diff --git a/libgo/go/golang_org/x/text/unicode/norm/readwriter.go b/libgo/go/golang_org/x/text/unicode/norm/readwriter.go
index d926ee9..482ac85 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/readwriter.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/readwriter.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
diff --git a/libgo/go/golang_org/x/text/unicode/norm/tables.go b/libgo/go/golang_org/x/text/unicode/norm/tables.go
index a56697b..ac99519 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/tables.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/tables.go
@@ -1,4 +1,6 @@
-// This file was generated by go generate; DO NOT EDIT
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
+// Code generated by running "go generate" in golang_org/x/text. DO NOT EDIT.
 
 package norm
 
@@ -27,14 +29,14 @@
 	firstMulti            = 0x186D
 	firstCCC              = 0x2C9E
 	endMulti              = 0x2F60
-	firstLeadingCCC       = 0x4A44
-	firstCCCZeroExcept    = 0x4A5A
-	firstStarterWithNLead = 0x4A81
-	lastDecomp            = 0x4A83
+	firstLeadingCCC       = 0x49AE
+	firstCCCZeroExcept    = 0x4A78
+	firstStarterWithNLead = 0x4A9F
+	lastDecomp            = 0x4AA1
 	maxDecomp             = 0x8000
 )
 
-// decomps: 19075 bytes
+// decomps: 19105 bytes
 var decomps = [...]byte{
 	// Bytes 0 - 3f
 	0x00, 0x41, 0x20, 0x41, 0x21, 0x41, 0x22, 0x41,
@@ -2443,283 +2445,287 @@
 	0xD9, 0x8F, 0x69, 0x43, 0x20, 0xD9, 0x90, 0x6D,
 	0x43, 0x20, 0xD9, 0x91, 0x71, 0x43, 0x20, 0xD9,
 	0x92, 0x75, 0x43, 0x41, 0xCC, 0x8A, 0xC9, 0x43,
-	0x73, 0xCC, 0x87, 0xC9, 0x43, 0xE1, 0x85, 0xA1,
-	0x01, 0x43, 0xE1, 0x85, 0xA2, 0x01, 0x43, 0xE1,
-	0x85, 0xA3, 0x01, 0x43, 0xE1, 0x85, 0xA4, 0x01,
-	0x43, 0xE1, 0x85, 0xA5, 0x01, 0x43, 0xE1, 0x85,
-	0xA6, 0x01, 0x43, 0xE1, 0x85, 0xA7, 0x01, 0x43,
+	0x73, 0xCC, 0x87, 0xC9, 0x44, 0x20, 0xE3, 0x82,
+	0x99, 0x0D, 0x44, 0x20, 0xE3, 0x82, 0x9A, 0x0D,
+	0x44, 0xC2, 0xA8, 0xCC, 0x81, 0xCA, 0x44, 0xCE,
+	0x91, 0xCC, 0x81, 0xC9, 0x44, 0xCE, 0x95, 0xCC,
+	0x81, 0xC9, 0x44, 0xCE, 0x97, 0xCC, 0x81, 0xC9,
 	// Bytes 4300 - 433f
-	0xE1, 0x85, 0xA8, 0x01, 0x43, 0xE1, 0x85, 0xA9,
-	0x01, 0x43, 0xE1, 0x85, 0xAA, 0x01, 0x43, 0xE1,
-	0x85, 0xAB, 0x01, 0x43, 0xE1, 0x85, 0xAC, 0x01,
-	0x43, 0xE1, 0x85, 0xAD, 0x01, 0x43, 0xE1, 0x85,
-	0xAE, 0x01, 0x43, 0xE1, 0x85, 0xAF, 0x01, 0x43,
-	0xE1, 0x85, 0xB0, 0x01, 0x43, 0xE1, 0x85, 0xB1,
-	0x01, 0x43, 0xE1, 0x85, 0xB2, 0x01, 0x43, 0xE1,
-	0x85, 0xB3, 0x01, 0x43, 0xE1, 0x85, 0xB4, 0x01,
+	0x44, 0xCE, 0x99, 0xCC, 0x81, 0xC9, 0x44, 0xCE,
+	0x9F, 0xCC, 0x81, 0xC9, 0x44, 0xCE, 0xA5, 0xCC,
+	0x81, 0xC9, 0x44, 0xCE, 0xA5, 0xCC, 0x88, 0xC9,
+	0x44, 0xCE, 0xA9, 0xCC, 0x81, 0xC9, 0x44, 0xCE,
+	0xB1, 0xCC, 0x81, 0xC9, 0x44, 0xCE, 0xB5, 0xCC,
+	0x81, 0xC9, 0x44, 0xCE, 0xB7, 0xCC, 0x81, 0xC9,
+	0x44, 0xCE, 0xB9, 0xCC, 0x81, 0xC9, 0x44, 0xCE,
+	0xBF, 0xCC, 0x81, 0xC9, 0x44, 0xCF, 0x85, 0xCC,
 	// Bytes 4340 - 437f
-	0x43, 0xE1, 0x85, 0xB5, 0x01, 0x43, 0xE1, 0x86,
-	0xAA, 0x01, 0x43, 0xE1, 0x86, 0xAC, 0x01, 0x43,
-	0xE1, 0x86, 0xAD, 0x01, 0x43, 0xE1, 0x86, 0xB0,
-	0x01, 0x43, 0xE1, 0x86, 0xB1, 0x01, 0x43, 0xE1,
-	0x86, 0xB2, 0x01, 0x43, 0xE1, 0x86, 0xB3, 0x01,
-	0x43, 0xE1, 0x86, 0xB4, 0x01, 0x43, 0xE1, 0x86,
-	0xB5, 0x01, 0x44, 0x20, 0xE3, 0x82, 0x99, 0x0D,
-	0x44, 0x20, 0xE3, 0x82, 0x9A, 0x0D, 0x44, 0xC2,
+	0x81, 0xC9, 0x44, 0xCF, 0x89, 0xCC, 0x81, 0xC9,
+	0x44, 0xD7, 0x90, 0xD6, 0xB7, 0x31, 0x44, 0xD7,
+	0x90, 0xD6, 0xB8, 0x35, 0x44, 0xD7, 0x90, 0xD6,
+	0xBC, 0x41, 0x44, 0xD7, 0x91, 0xD6, 0xBC, 0x41,
+	0x44, 0xD7, 0x91, 0xD6, 0xBF, 0x49, 0x44, 0xD7,
+	0x92, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0x93, 0xD6,
+	0xBC, 0x41, 0x44, 0xD7, 0x94, 0xD6, 0xBC, 0x41,
+	0x44, 0xD7, 0x95, 0xD6, 0xB9, 0x39, 0x44, 0xD7,
 	// Bytes 4380 - 43bf
-	0xA8, 0xCC, 0x81, 0xCA, 0x44, 0xCE, 0x91, 0xCC,
-	0x81, 0xC9, 0x44, 0xCE, 0x95, 0xCC, 0x81, 0xC9,
-	0x44, 0xCE, 0x97, 0xCC, 0x81, 0xC9, 0x44, 0xCE,
-	0x99, 0xCC, 0x81, 0xC9, 0x44, 0xCE, 0x9F, 0xCC,
-	0x81, 0xC9, 0x44, 0xCE, 0xA5, 0xCC, 0x81, 0xC9,
-	0x44, 0xCE, 0xA5, 0xCC, 0x88, 0xC9, 0x44, 0xCE,
-	0xA9, 0xCC, 0x81, 0xC9, 0x44, 0xCE, 0xB1, 0xCC,
-	0x81, 0xC9, 0x44, 0xCE, 0xB5, 0xCC, 0x81, 0xC9,
+	0x95, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0x96, 0xD6,
+	0xBC, 0x41, 0x44, 0xD7, 0x98, 0xD6, 0xBC, 0x41,
+	0x44, 0xD7, 0x99, 0xD6, 0xB4, 0x25, 0x44, 0xD7,
+	0x99, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0x9A, 0xD6,
+	0xBC, 0x41, 0x44, 0xD7, 0x9B, 0xD6, 0xBC, 0x41,
+	0x44, 0xD7, 0x9B, 0xD6, 0xBF, 0x49, 0x44, 0xD7,
+	0x9C, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0x9E, 0xD6,
+	0xBC, 0x41, 0x44, 0xD7, 0xA0, 0xD6, 0xBC, 0x41,
 	// Bytes 43c0 - 43ff
-	0x44, 0xCE, 0xB7, 0xCC, 0x81, 0xC9, 0x44, 0xCE,
-	0xB9, 0xCC, 0x81, 0xC9, 0x44, 0xCE, 0xBF, 0xCC,
-	0x81, 0xC9, 0x44, 0xCF, 0x85, 0xCC, 0x81, 0xC9,
-	0x44, 0xCF, 0x89, 0xCC, 0x81, 0xC9, 0x44, 0xD7,
-	0x90, 0xD6, 0xB7, 0x31, 0x44, 0xD7, 0x90, 0xD6,
-	0xB8, 0x35, 0x44, 0xD7, 0x90, 0xD6, 0xBC, 0x41,
-	0x44, 0xD7, 0x91, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
-	0x91, 0xD6, 0xBF, 0x49, 0x44, 0xD7, 0x92, 0xD6,
+	0x44, 0xD7, 0xA1, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
+	0xA3, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0xA4, 0xD6,
+	0xBC, 0x41, 0x44, 0xD7, 0xA4, 0xD6, 0xBF, 0x49,
+	0x44, 0xD7, 0xA6, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
+	0xA7, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0xA8, 0xD6,
+	0xBC, 0x41, 0x44, 0xD7, 0xA9, 0xD6, 0xBC, 0x41,
+	0x44, 0xD7, 0xA9, 0xD7, 0x81, 0x4D, 0x44, 0xD7,
+	0xA9, 0xD7, 0x82, 0x51, 0x44, 0xD7, 0xAA, 0xD6,
 	// Bytes 4400 - 443f
-	0xBC, 0x41, 0x44, 0xD7, 0x93, 0xD6, 0xBC, 0x41,
-	0x44, 0xD7, 0x94, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
-	0x95, 0xD6, 0xB9, 0x39, 0x44, 0xD7, 0x95, 0xD6,
-	0xBC, 0x41, 0x44, 0xD7, 0x96, 0xD6, 0xBC, 0x41,
-	0x44, 0xD7, 0x98, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
-	0x99, 0xD6, 0xB4, 0x25, 0x44, 0xD7, 0x99, 0xD6,
-	0xBC, 0x41, 0x44, 0xD7, 0x9A, 0xD6, 0xBC, 0x41,
-	0x44, 0xD7, 0x9B, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
+	0xBC, 0x41, 0x44, 0xD7, 0xB2, 0xD6, 0xB7, 0x31,
+	0x44, 0xD8, 0xA7, 0xD9, 0x8B, 0x59, 0x44, 0xD8,
+	0xA7, 0xD9, 0x93, 0xC9, 0x44, 0xD8, 0xA7, 0xD9,
+	0x94, 0xC9, 0x44, 0xD8, 0xA7, 0xD9, 0x95, 0xB5,
+	0x44, 0xD8, 0xB0, 0xD9, 0xB0, 0x79, 0x44, 0xD8,
+	0xB1, 0xD9, 0xB0, 0x79, 0x44, 0xD9, 0x80, 0xD9,
+	0x8B, 0x59, 0x44, 0xD9, 0x80, 0xD9, 0x8E, 0x65,
+	0x44, 0xD9, 0x80, 0xD9, 0x8F, 0x69, 0x44, 0xD9,
 	// Bytes 4440 - 447f
-	0x9B, 0xD6, 0xBF, 0x49, 0x44, 0xD7, 0x9C, 0xD6,
-	0xBC, 0x41, 0x44, 0xD7, 0x9E, 0xD6, 0xBC, 0x41,
-	0x44, 0xD7, 0xA0, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
-	0xA1, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0xA3, 0xD6,
-	0xBC, 0x41, 0x44, 0xD7, 0xA4, 0xD6, 0xBC, 0x41,
-	0x44, 0xD7, 0xA4, 0xD6, 0xBF, 0x49, 0x44, 0xD7,
-	0xA6, 0xD6, 0xBC, 0x41, 0x44, 0xD7, 0xA7, 0xD6,
-	0xBC, 0x41, 0x44, 0xD7, 0xA8, 0xD6, 0xBC, 0x41,
+	0x80, 0xD9, 0x90, 0x6D, 0x44, 0xD9, 0x80, 0xD9,
+	0x91, 0x71, 0x44, 0xD9, 0x80, 0xD9, 0x92, 0x75,
+	0x44, 0xD9, 0x87, 0xD9, 0xB0, 0x79, 0x44, 0xD9,
+	0x88, 0xD9, 0x94, 0xC9, 0x44, 0xD9, 0x89, 0xD9,
+	0xB0, 0x79, 0x44, 0xD9, 0x8A, 0xD9, 0x94, 0xC9,
+	0x44, 0xDB, 0x92, 0xD9, 0x94, 0xC9, 0x44, 0xDB,
+	0x95, 0xD9, 0x94, 0xC9, 0x45, 0x20, 0xCC, 0x88,
+	0xCC, 0x80, 0xCA, 0x45, 0x20, 0xCC, 0x88, 0xCC,
 	// Bytes 4480 - 44bf
-	0x44, 0xD7, 0xA9, 0xD6, 0xBC, 0x41, 0x44, 0xD7,
-	0xA9, 0xD7, 0x81, 0x4D, 0x44, 0xD7, 0xA9, 0xD7,
-	0x82, 0x51, 0x44, 0xD7, 0xAA, 0xD6, 0xBC, 0x41,
-	0x44, 0xD7, 0xB2, 0xD6, 0xB7, 0x31, 0x44, 0xD8,
-	0xA7, 0xD9, 0x8B, 0x59, 0x44, 0xD8, 0xA7, 0xD9,
-	0x93, 0xC9, 0x44, 0xD8, 0xA7, 0xD9, 0x94, 0xC9,
-	0x44, 0xD8, 0xA7, 0xD9, 0x95, 0xB5, 0x44, 0xD8,
-	0xB0, 0xD9, 0xB0, 0x79, 0x44, 0xD8, 0xB1, 0xD9,
+	0x81, 0xCA, 0x45, 0x20, 0xCC, 0x88, 0xCD, 0x82,
+	0xCA, 0x45, 0x20, 0xCC, 0x93, 0xCC, 0x80, 0xCA,
+	0x45, 0x20, 0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x45,
+	0x20, 0xCC, 0x93, 0xCD, 0x82, 0xCA, 0x45, 0x20,
+	0xCC, 0x94, 0xCC, 0x80, 0xCA, 0x45, 0x20, 0xCC,
+	0x94, 0xCC, 0x81, 0xCA, 0x45, 0x20, 0xCC, 0x94,
+	0xCD, 0x82, 0xCA, 0x45, 0x20, 0xD9, 0x8C, 0xD9,
+	0x91, 0x72, 0x45, 0x20, 0xD9, 0x8D, 0xD9, 0x91,
 	// Bytes 44c0 - 44ff
-	0xB0, 0x79, 0x44, 0xD9, 0x80, 0xD9, 0x8B, 0x59,
-	0x44, 0xD9, 0x80, 0xD9, 0x8E, 0x65, 0x44, 0xD9,
-	0x80, 0xD9, 0x8F, 0x69, 0x44, 0xD9, 0x80, 0xD9,
-	0x90, 0x6D, 0x44, 0xD9, 0x80, 0xD9, 0x91, 0x71,
-	0x44, 0xD9, 0x80, 0xD9, 0x92, 0x75, 0x44, 0xD9,
-	0x87, 0xD9, 0xB0, 0x79, 0x44, 0xD9, 0x88, 0xD9,
-	0x94, 0xC9, 0x44, 0xD9, 0x89, 0xD9, 0xB0, 0x79,
-	0x44, 0xD9, 0x8A, 0xD9, 0x94, 0xC9, 0x44, 0xDB,
+	0x72, 0x45, 0x20, 0xD9, 0x8E, 0xD9, 0x91, 0x72,
+	0x45, 0x20, 0xD9, 0x8F, 0xD9, 0x91, 0x72, 0x45,
+	0x20, 0xD9, 0x90, 0xD9, 0x91, 0x72, 0x45, 0x20,
+	0xD9, 0x91, 0xD9, 0xB0, 0x7A, 0x45, 0xE2, 0xAB,
+	0x9D, 0xCC, 0xB8, 0x05, 0x46, 0xCE, 0xB9, 0xCC,
+	0x88, 0xCC, 0x81, 0xCA, 0x46, 0xCF, 0x85, 0xCC,
+	0x88, 0xCC, 0x81, 0xCA, 0x46, 0xD7, 0xA9, 0xD6,
+	0xBC, 0xD7, 0x81, 0x4E, 0x46, 0xD7, 0xA9, 0xD6,
 	// Bytes 4500 - 453f
-	0x92, 0xD9, 0x94, 0xC9, 0x44, 0xDB, 0x95, 0xD9,
-	0x94, 0xC9, 0x45, 0x20, 0xCC, 0x88, 0xCC, 0x80,
-	0xCA, 0x45, 0x20, 0xCC, 0x88, 0xCC, 0x81, 0xCA,
-	0x45, 0x20, 0xCC, 0x88, 0xCD, 0x82, 0xCA, 0x45,
-	0x20, 0xCC, 0x93, 0xCC, 0x80, 0xCA, 0x45, 0x20,
-	0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x45, 0x20, 0xCC,
-	0x93, 0xCD, 0x82, 0xCA, 0x45, 0x20, 0xCC, 0x94,
-	0xCC, 0x80, 0xCA, 0x45, 0x20, 0xCC, 0x94, 0xCC,
+	0xBC, 0xD7, 0x82, 0x52, 0x46, 0xD9, 0x80, 0xD9,
+	0x8E, 0xD9, 0x91, 0x72, 0x46, 0xD9, 0x80, 0xD9,
+	0x8F, 0xD9, 0x91, 0x72, 0x46, 0xD9, 0x80, 0xD9,
+	0x90, 0xD9, 0x91, 0x72, 0x46, 0xE0, 0xA4, 0x95,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA4, 0x96,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA4, 0x97,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA4, 0x9C,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xA1,
 	// Bytes 4540 - 457f
-	0x81, 0xCA, 0x45, 0x20, 0xCC, 0x94, 0xCD, 0x82,
-	0xCA, 0x45, 0x20, 0xD9, 0x8C, 0xD9, 0x91, 0x72,
-	0x45, 0x20, 0xD9, 0x8D, 0xD9, 0x91, 0x72, 0x45,
-	0x20, 0xD9, 0x8E, 0xD9, 0x91, 0x72, 0x45, 0x20,
-	0xD9, 0x8F, 0xD9, 0x91, 0x72, 0x45, 0x20, 0xD9,
-	0x90, 0xD9, 0x91, 0x72, 0x45, 0x20, 0xD9, 0x91,
-	0xD9, 0xB0, 0x7A, 0x45, 0xE2, 0xAB, 0x9D, 0xCC,
-	0xB8, 0x05, 0x46, 0xCE, 0xB9, 0xCC, 0x88, 0xCC,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xA2,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xAB,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xAF,
+	0xE0, 0xA4, 0xBC, 0x09, 0x46, 0xE0, 0xA6, 0xA1,
+	0xE0, 0xA6, 0xBC, 0x09, 0x46, 0xE0, 0xA6, 0xA2,
+	0xE0, 0xA6, 0xBC, 0x09, 0x46, 0xE0, 0xA6, 0xAF,
+	0xE0, 0xA6, 0xBC, 0x09, 0x46, 0xE0, 0xA8, 0x96,
+	0xE0, 0xA8, 0xBC, 0x09, 0x46, 0xE0, 0xA8, 0x97,
 	// Bytes 4580 - 45bf
-	0x81, 0xCA, 0x46, 0xCF, 0x85, 0xCC, 0x88, 0xCC,
-	0x81, 0xCA, 0x46, 0xD7, 0xA9, 0xD6, 0xBC, 0xD7,
-	0x81, 0x4E, 0x46, 0xD7, 0xA9, 0xD6, 0xBC, 0xD7,
-	0x82, 0x52, 0x46, 0xD9, 0x80, 0xD9, 0x8E, 0xD9,
-	0x91, 0x72, 0x46, 0xD9, 0x80, 0xD9, 0x8F, 0xD9,
-	0x91, 0x72, 0x46, 0xD9, 0x80, 0xD9, 0x90, 0xD9,
-	0x91, 0x72, 0x46, 0xE0, 0xA4, 0x95, 0xE0, 0xA4,
-	0xBC, 0x09, 0x46, 0xE0, 0xA4, 0x96, 0xE0, 0xA4,
+	0xE0, 0xA8, 0xBC, 0x09, 0x46, 0xE0, 0xA8, 0x9C,
+	0xE0, 0xA8, 0xBC, 0x09, 0x46, 0xE0, 0xA8, 0xAB,
+	0xE0, 0xA8, 0xBC, 0x09, 0x46, 0xE0, 0xA8, 0xB2,
+	0xE0, 0xA8, 0xBC, 0x09, 0x46, 0xE0, 0xA8, 0xB8,
+	0xE0, 0xA8, 0xBC, 0x09, 0x46, 0xE0, 0xAC, 0xA1,
+	0xE0, 0xAC, 0xBC, 0x09, 0x46, 0xE0, 0xAC, 0xA2,
+	0xE0, 0xAC, 0xBC, 0x09, 0x46, 0xE0, 0xBE, 0xB2,
+	0xE0, 0xBE, 0x80, 0x9D, 0x46, 0xE0, 0xBE, 0xB3,
 	// Bytes 45c0 - 45ff
-	0xBC, 0x09, 0x46, 0xE0, 0xA4, 0x97, 0xE0, 0xA4,
-	0xBC, 0x09, 0x46, 0xE0, 0xA4, 0x9C, 0xE0, 0xA4,
-	0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xA1, 0xE0, 0xA4,
-	0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xA2, 0xE0, 0xA4,
-	0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xAB, 0xE0, 0xA4,
-	0xBC, 0x09, 0x46, 0xE0, 0xA4, 0xAF, 0xE0, 0xA4,
-	0xBC, 0x09, 0x46, 0xE0, 0xA6, 0xA1, 0xE0, 0xA6,
-	0xBC, 0x09, 0x46, 0xE0, 0xA6, 0xA2, 0xE0, 0xA6,
+	0xE0, 0xBE, 0x80, 0x9D, 0x46, 0xE3, 0x83, 0x86,
+	0xE3, 0x82, 0x99, 0x0D, 0x48, 0xF0, 0x9D, 0x85,
+	0x97, 0xF0, 0x9D, 0x85, 0xA5, 0xAD, 0x48, 0xF0,
+	0x9D, 0x85, 0x98, 0xF0, 0x9D, 0x85, 0xA5, 0xAD,
+	0x48, 0xF0, 0x9D, 0x86, 0xB9, 0xF0, 0x9D, 0x85,
+	0xA5, 0xAD, 0x48, 0xF0, 0x9D, 0x86, 0xBA, 0xF0,
+	0x9D, 0x85, 0xA5, 0xAD, 0x49, 0xE0, 0xBE, 0xB2,
+	0xE0, 0xBD, 0xB1, 0xE0, 0xBE, 0x80, 0x9E, 0x49,
 	// Bytes 4600 - 463f
-	0xBC, 0x09, 0x46, 0xE0, 0xA6, 0xAF, 0xE0, 0xA6,
-	0xBC, 0x09, 0x46, 0xE0, 0xA8, 0x96, 0xE0, 0xA8,
-	0xBC, 0x09, 0x46, 0xE0, 0xA8, 0x97, 0xE0, 0xA8,
-	0xBC, 0x09, 0x46, 0xE0, 0xA8, 0x9C, 0xE0, 0xA8,
-	0xBC, 0x09, 0x46, 0xE0, 0xA8, 0xAB, 0xE0, 0xA8,
-	0xBC, 0x09, 0x46, 0xE0, 0xA8, 0xB2, 0xE0, 0xA8,
-	0xBC, 0x09, 0x46, 0xE0, 0xA8, 0xB8, 0xE0, 0xA8,
-	0xBC, 0x09, 0x46, 0xE0, 0xAC, 0xA1, 0xE0, 0xAC,
-	// Bytes 4640 - 467f
-	0xBC, 0x09, 0x46, 0xE0, 0xAC, 0xA2, 0xE0, 0xAC,
-	0xBC, 0x09, 0x46, 0xE0, 0xBE, 0xB2, 0xE0, 0xBE,
-	0x80, 0x9D, 0x46, 0xE0, 0xBE, 0xB3, 0xE0, 0xBE,
-	0x80, 0x9D, 0x46, 0xE3, 0x83, 0x86, 0xE3, 0x82,
-	0x99, 0x0D, 0x48, 0xF0, 0x9D, 0x85, 0x97, 0xF0,
-	0x9D, 0x85, 0xA5, 0xAD, 0x48, 0xF0, 0x9D, 0x85,
-	0x98, 0xF0, 0x9D, 0x85, 0xA5, 0xAD, 0x48, 0xF0,
-	0x9D, 0x86, 0xB9, 0xF0, 0x9D, 0x85, 0xA5, 0xAD,
-	// Bytes 4680 - 46bf
-	0x48, 0xF0, 0x9D, 0x86, 0xBA, 0xF0, 0x9D, 0x85,
-	0xA5, 0xAD, 0x49, 0xE0, 0xBE, 0xB2, 0xE0, 0xBD,
-	0xB1, 0xE0, 0xBE, 0x80, 0x9E, 0x49, 0xE0, 0xBE,
-	0xB3, 0xE0, 0xBD, 0xB1, 0xE0, 0xBE, 0x80, 0x9E,
-	0x4C, 0xF0, 0x9D, 0x85, 0x98, 0xF0, 0x9D, 0x85,
-	0xA5, 0xF0, 0x9D, 0x85, 0xAE, 0xAE, 0x4C, 0xF0,
-	0x9D, 0x85, 0x98, 0xF0, 0x9D, 0x85, 0xA5, 0xF0,
-	0x9D, 0x85, 0xAF, 0xAE, 0x4C, 0xF0, 0x9D, 0x85,
-	// Bytes 46c0 - 46ff
-	0x98, 0xF0, 0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85,
-	0xB0, 0xAE, 0x4C, 0xF0, 0x9D, 0x85, 0x98, 0xF0,
-	0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85, 0xB1, 0xAE,
-	0x4C, 0xF0, 0x9D, 0x85, 0x98, 0xF0, 0x9D, 0x85,
-	0xA5, 0xF0, 0x9D, 0x85, 0xB2, 0xAE, 0x4C, 0xF0,
-	0x9D, 0x86, 0xB9, 0xF0, 0x9D, 0x85, 0xA5, 0xF0,
-	0x9D, 0x85, 0xAE, 0xAE, 0x4C, 0xF0, 0x9D, 0x86,
-	0xB9, 0xF0, 0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85,
-	// Bytes 4700 - 473f
-	0xAF, 0xAE, 0x4C, 0xF0, 0x9D, 0x86, 0xBA, 0xF0,
+	0xE0, 0xBE, 0xB3, 0xE0, 0xBD, 0xB1, 0xE0, 0xBE,
+	0x80, 0x9E, 0x4C, 0xF0, 0x9D, 0x85, 0x98, 0xF0,
 	0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85, 0xAE, 0xAE,
-	0x4C, 0xF0, 0x9D, 0x86, 0xBA, 0xF0, 0x9D, 0x85,
-	0xA5, 0xF0, 0x9D, 0x85, 0xAF, 0xAE, 0x83, 0x41,
-	0xCC, 0x82, 0xC9, 0x83, 0x41, 0xCC, 0x86, 0xC9,
-	0x83, 0x41, 0xCC, 0x87, 0xC9, 0x83, 0x41, 0xCC,
-	0x88, 0xC9, 0x83, 0x41, 0xCC, 0x8A, 0xC9, 0x83,
-	0x41, 0xCC, 0xA3, 0xB5, 0x83, 0x43, 0xCC, 0xA7,
+	0x4C, 0xF0, 0x9D, 0x85, 0x98, 0xF0, 0x9D, 0x85,
+	0xA5, 0xF0, 0x9D, 0x85, 0xAF, 0xAE, 0x4C, 0xF0,
+	0x9D, 0x85, 0x98, 0xF0, 0x9D, 0x85, 0xA5, 0xF0,
+	0x9D, 0x85, 0xB0, 0xAE, 0x4C, 0xF0, 0x9D, 0x85,
+	0x98, 0xF0, 0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85,
+	// Bytes 4640 - 467f
+	0xB1, 0xAE, 0x4C, 0xF0, 0x9D, 0x85, 0x98, 0xF0,
+	0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85, 0xB2, 0xAE,
+	0x4C, 0xF0, 0x9D, 0x86, 0xB9, 0xF0, 0x9D, 0x85,
+	0xA5, 0xF0, 0x9D, 0x85, 0xAE, 0xAE, 0x4C, 0xF0,
+	0x9D, 0x86, 0xB9, 0xF0, 0x9D, 0x85, 0xA5, 0xF0,
+	0x9D, 0x85, 0xAF, 0xAE, 0x4C, 0xF0, 0x9D, 0x86,
+	0xBA, 0xF0, 0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85,
+	0xAE, 0xAE, 0x4C, 0xF0, 0x9D, 0x86, 0xBA, 0xF0,
+	// Bytes 4680 - 46bf
+	0x9D, 0x85, 0xA5, 0xF0, 0x9D, 0x85, 0xAF, 0xAE,
+	0x83, 0x41, 0xCC, 0x82, 0xC9, 0x83, 0x41, 0xCC,
+	0x86, 0xC9, 0x83, 0x41, 0xCC, 0x87, 0xC9, 0x83,
+	0x41, 0xCC, 0x88, 0xC9, 0x83, 0x41, 0xCC, 0x8A,
+	0xC9, 0x83, 0x41, 0xCC, 0xA3, 0xB5, 0x83, 0x43,
+	0xCC, 0xA7, 0xA5, 0x83, 0x45, 0xCC, 0x82, 0xC9,
+	0x83, 0x45, 0xCC, 0x84, 0xC9, 0x83, 0x45, 0xCC,
+	0xA3, 0xB5, 0x83, 0x45, 0xCC, 0xA7, 0xA5, 0x83,
+	// Bytes 46c0 - 46ff
+	0x49, 0xCC, 0x88, 0xC9, 0x83, 0x4C, 0xCC, 0xA3,
+	0xB5, 0x83, 0x4F, 0xCC, 0x82, 0xC9, 0x83, 0x4F,
+	0xCC, 0x83, 0xC9, 0x83, 0x4F, 0xCC, 0x84, 0xC9,
+	0x83, 0x4F, 0xCC, 0x87, 0xC9, 0x83, 0x4F, 0xCC,
+	0x88, 0xC9, 0x83, 0x4F, 0xCC, 0x9B, 0xAD, 0x83,
+	0x4F, 0xCC, 0xA3, 0xB5, 0x83, 0x4F, 0xCC, 0xA8,
+	0xA5, 0x83, 0x52, 0xCC, 0xA3, 0xB5, 0x83, 0x53,
+	0xCC, 0x81, 0xC9, 0x83, 0x53, 0xCC, 0x8C, 0xC9,
+	// Bytes 4700 - 473f
+	0x83, 0x53, 0xCC, 0xA3, 0xB5, 0x83, 0x55, 0xCC,
+	0x83, 0xC9, 0x83, 0x55, 0xCC, 0x84, 0xC9, 0x83,
+	0x55, 0xCC, 0x88, 0xC9, 0x83, 0x55, 0xCC, 0x9B,
+	0xAD, 0x83, 0x61, 0xCC, 0x82, 0xC9, 0x83, 0x61,
+	0xCC, 0x86, 0xC9, 0x83, 0x61, 0xCC, 0x87, 0xC9,
+	0x83, 0x61, 0xCC, 0x88, 0xC9, 0x83, 0x61, 0xCC,
+	0x8A, 0xC9, 0x83, 0x61, 0xCC, 0xA3, 0xB5, 0x83,
+	0x63, 0xCC, 0xA7, 0xA5, 0x83, 0x65, 0xCC, 0x82,
 	// Bytes 4740 - 477f
-	0xA5, 0x83, 0x45, 0xCC, 0x82, 0xC9, 0x83, 0x45,
-	0xCC, 0x84, 0xC9, 0x83, 0x45, 0xCC, 0xA3, 0xB5,
-	0x83, 0x45, 0xCC, 0xA7, 0xA5, 0x83, 0x49, 0xCC,
-	0x88, 0xC9, 0x83, 0x4C, 0xCC, 0xA3, 0xB5, 0x83,
-	0x4F, 0xCC, 0x82, 0xC9, 0x83, 0x4F, 0xCC, 0x83,
-	0xC9, 0x83, 0x4F, 0xCC, 0x84, 0xC9, 0x83, 0x4F,
-	0xCC, 0x87, 0xC9, 0x83, 0x4F, 0xCC, 0x88, 0xC9,
-	0x83, 0x4F, 0xCC, 0x9B, 0xAD, 0x83, 0x4F, 0xCC,
+	0xC9, 0x83, 0x65, 0xCC, 0x84, 0xC9, 0x83, 0x65,
+	0xCC, 0xA3, 0xB5, 0x83, 0x65, 0xCC, 0xA7, 0xA5,
+	0x83, 0x69, 0xCC, 0x88, 0xC9, 0x83, 0x6C, 0xCC,
+	0xA3, 0xB5, 0x83, 0x6F, 0xCC, 0x82, 0xC9, 0x83,
+	0x6F, 0xCC, 0x83, 0xC9, 0x83, 0x6F, 0xCC, 0x84,
+	0xC9, 0x83, 0x6F, 0xCC, 0x87, 0xC9, 0x83, 0x6F,
+	0xCC, 0x88, 0xC9, 0x83, 0x6F, 0xCC, 0x9B, 0xAD,
+	0x83, 0x6F, 0xCC, 0xA3, 0xB5, 0x83, 0x6F, 0xCC,
 	// Bytes 4780 - 47bf
-	0xA3, 0xB5, 0x83, 0x4F, 0xCC, 0xA8, 0xA5, 0x83,
-	0x52, 0xCC, 0xA3, 0xB5, 0x83, 0x53, 0xCC, 0x81,
-	0xC9, 0x83, 0x53, 0xCC, 0x8C, 0xC9, 0x83, 0x53,
-	0xCC, 0xA3, 0xB5, 0x83, 0x55, 0xCC, 0x83, 0xC9,
-	0x83, 0x55, 0xCC, 0x84, 0xC9, 0x83, 0x55, 0xCC,
-	0x88, 0xC9, 0x83, 0x55, 0xCC, 0x9B, 0xAD, 0x83,
-	0x61, 0xCC, 0x82, 0xC9, 0x83, 0x61, 0xCC, 0x86,
-	0xC9, 0x83, 0x61, 0xCC, 0x87, 0xC9, 0x83, 0x61,
+	0xA8, 0xA5, 0x83, 0x72, 0xCC, 0xA3, 0xB5, 0x83,
+	0x73, 0xCC, 0x81, 0xC9, 0x83, 0x73, 0xCC, 0x8C,
+	0xC9, 0x83, 0x73, 0xCC, 0xA3, 0xB5, 0x83, 0x75,
+	0xCC, 0x83, 0xC9, 0x83, 0x75, 0xCC, 0x84, 0xC9,
+	0x83, 0x75, 0xCC, 0x88, 0xC9, 0x83, 0x75, 0xCC,
+	0x9B, 0xAD, 0x84, 0xCE, 0x91, 0xCC, 0x93, 0xC9,
+	0x84, 0xCE, 0x91, 0xCC, 0x94, 0xC9, 0x84, 0xCE,
+	0x95, 0xCC, 0x93, 0xC9, 0x84, 0xCE, 0x95, 0xCC,
 	// Bytes 47c0 - 47ff
-	0xCC, 0x88, 0xC9, 0x83, 0x61, 0xCC, 0x8A, 0xC9,
-	0x83, 0x61, 0xCC, 0xA3, 0xB5, 0x83, 0x63, 0xCC,
-	0xA7, 0xA5, 0x83, 0x65, 0xCC, 0x82, 0xC9, 0x83,
-	0x65, 0xCC, 0x84, 0xC9, 0x83, 0x65, 0xCC, 0xA3,
-	0xB5, 0x83, 0x65, 0xCC, 0xA7, 0xA5, 0x83, 0x69,
-	0xCC, 0x88, 0xC9, 0x83, 0x6C, 0xCC, 0xA3, 0xB5,
-	0x83, 0x6F, 0xCC, 0x82, 0xC9, 0x83, 0x6F, 0xCC,
-	0x83, 0xC9, 0x83, 0x6F, 0xCC, 0x84, 0xC9, 0x83,
+	0x94, 0xC9, 0x84, 0xCE, 0x97, 0xCC, 0x93, 0xC9,
+	0x84, 0xCE, 0x97, 0xCC, 0x94, 0xC9, 0x84, 0xCE,
+	0x99, 0xCC, 0x93, 0xC9, 0x84, 0xCE, 0x99, 0xCC,
+	0x94, 0xC9, 0x84, 0xCE, 0x9F, 0xCC, 0x93, 0xC9,
+	0x84, 0xCE, 0x9F, 0xCC, 0x94, 0xC9, 0x84, 0xCE,
+	0xA5, 0xCC, 0x94, 0xC9, 0x84, 0xCE, 0xA9, 0xCC,
+	0x93, 0xC9, 0x84, 0xCE, 0xA9, 0xCC, 0x94, 0xC9,
+	0x84, 0xCE, 0xB1, 0xCC, 0x80, 0xC9, 0x84, 0xCE,
 	// Bytes 4800 - 483f
-	0x6F, 0xCC, 0x87, 0xC9, 0x83, 0x6F, 0xCC, 0x88,
-	0xC9, 0x83, 0x6F, 0xCC, 0x9B, 0xAD, 0x83, 0x6F,
-	0xCC, 0xA3, 0xB5, 0x83, 0x6F, 0xCC, 0xA8, 0xA5,
-	0x83, 0x72, 0xCC, 0xA3, 0xB5, 0x83, 0x73, 0xCC,
-	0x81, 0xC9, 0x83, 0x73, 0xCC, 0x8C, 0xC9, 0x83,
-	0x73, 0xCC, 0xA3, 0xB5, 0x83, 0x75, 0xCC, 0x83,
-	0xC9, 0x83, 0x75, 0xCC, 0x84, 0xC9, 0x83, 0x75,
-	0xCC, 0x88, 0xC9, 0x83, 0x75, 0xCC, 0x9B, 0xAD,
+	0xB1, 0xCC, 0x81, 0xC9, 0x84, 0xCE, 0xB1, 0xCC,
+	0x93, 0xC9, 0x84, 0xCE, 0xB1, 0xCC, 0x94, 0xC9,
+	0x84, 0xCE, 0xB1, 0xCD, 0x82, 0xC9, 0x84, 0xCE,
+	0xB5, 0xCC, 0x93, 0xC9, 0x84, 0xCE, 0xB5, 0xCC,
+	0x94, 0xC9, 0x84, 0xCE, 0xB7, 0xCC, 0x80, 0xC9,
+	0x84, 0xCE, 0xB7, 0xCC, 0x81, 0xC9, 0x84, 0xCE,
+	0xB7, 0xCC, 0x93, 0xC9, 0x84, 0xCE, 0xB7, 0xCC,
+	0x94, 0xC9, 0x84, 0xCE, 0xB7, 0xCD, 0x82, 0xC9,
 	// Bytes 4840 - 487f
-	0x84, 0xCE, 0x91, 0xCC, 0x93, 0xC9, 0x84, 0xCE,
-	0x91, 0xCC, 0x94, 0xC9, 0x84, 0xCE, 0x95, 0xCC,
-	0x93, 0xC9, 0x84, 0xCE, 0x95, 0xCC, 0x94, 0xC9,
-	0x84, 0xCE, 0x97, 0xCC, 0x93, 0xC9, 0x84, 0xCE,
-	0x97, 0xCC, 0x94, 0xC9, 0x84, 0xCE, 0x99, 0xCC,
-	0x93, 0xC9, 0x84, 0xCE, 0x99, 0xCC, 0x94, 0xC9,
-	0x84, 0xCE, 0x9F, 0xCC, 0x93, 0xC9, 0x84, 0xCE,
-	0x9F, 0xCC, 0x94, 0xC9, 0x84, 0xCE, 0xA5, 0xCC,
+	0x84, 0xCE, 0xB9, 0xCC, 0x88, 0xC9, 0x84, 0xCE,
+	0xB9, 0xCC, 0x93, 0xC9, 0x84, 0xCE, 0xB9, 0xCC,
+	0x94, 0xC9, 0x84, 0xCE, 0xBF, 0xCC, 0x93, 0xC9,
+	0x84, 0xCE, 0xBF, 0xCC, 0x94, 0xC9, 0x84, 0xCF,
+	0x85, 0xCC, 0x88, 0xC9, 0x84, 0xCF, 0x85, 0xCC,
+	0x93, 0xC9, 0x84, 0xCF, 0x85, 0xCC, 0x94, 0xC9,
+	0x84, 0xCF, 0x89, 0xCC, 0x80, 0xC9, 0x84, 0xCF,
+	0x89, 0xCC, 0x81, 0xC9, 0x84, 0xCF, 0x89, 0xCC,
 	// Bytes 4880 - 48bf
-	0x94, 0xC9, 0x84, 0xCE, 0xA9, 0xCC, 0x93, 0xC9,
-	0x84, 0xCE, 0xA9, 0xCC, 0x94, 0xC9, 0x84, 0xCE,
-	0xB1, 0xCC, 0x80, 0xC9, 0x84, 0xCE, 0xB1, 0xCC,
-	0x81, 0xC9, 0x84, 0xCE, 0xB1, 0xCC, 0x93, 0xC9,
-	0x84, 0xCE, 0xB1, 0xCC, 0x94, 0xC9, 0x84, 0xCE,
-	0xB1, 0xCD, 0x82, 0xC9, 0x84, 0xCE, 0xB5, 0xCC,
-	0x93, 0xC9, 0x84, 0xCE, 0xB5, 0xCC, 0x94, 0xC9,
-	0x84, 0xCE, 0xB7, 0xCC, 0x80, 0xC9, 0x84, 0xCE,
+	0x93, 0xC9, 0x84, 0xCF, 0x89, 0xCC, 0x94, 0xC9,
+	0x84, 0xCF, 0x89, 0xCD, 0x82, 0xC9, 0x86, 0xCE,
+	0x91, 0xCC, 0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0x91, 0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0x91, 0xCC, 0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0x91, 0xCC, 0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0x91, 0xCC, 0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0x91, 0xCC, 0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
 	// Bytes 48c0 - 48ff
-	0xB7, 0xCC, 0x81, 0xC9, 0x84, 0xCE, 0xB7, 0xCC,
-	0x93, 0xC9, 0x84, 0xCE, 0xB7, 0xCC, 0x94, 0xC9,
-	0x84, 0xCE, 0xB7, 0xCD, 0x82, 0xC9, 0x84, 0xCE,
-	0xB9, 0xCC, 0x88, 0xC9, 0x84, 0xCE, 0xB9, 0xCC,
-	0x93, 0xC9, 0x84, 0xCE, 0xB9, 0xCC, 0x94, 0xC9,
-	0x84, 0xCE, 0xBF, 0xCC, 0x93, 0xC9, 0x84, 0xCE,
-	0xBF, 0xCC, 0x94, 0xC9, 0x84, 0xCF, 0x85, 0xCC,
-	0x88, 0xC9, 0x84, 0xCF, 0x85, 0xCC, 0x93, 0xC9,
+	0x97, 0xCC, 0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0x97, 0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0x97, 0xCC, 0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0x97, 0xCC, 0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0x97, 0xCC, 0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0x97, 0xCC, 0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0xA9, 0xCC, 0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0xA9, 0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
 	// Bytes 4900 - 493f
-	0x84, 0xCF, 0x85, 0xCC, 0x94, 0xC9, 0x84, 0xCF,
-	0x89, 0xCC, 0x80, 0xC9, 0x84, 0xCF, 0x89, 0xCC,
-	0x81, 0xC9, 0x84, 0xCF, 0x89, 0xCC, 0x93, 0xC9,
-	0x84, 0xCF, 0x89, 0xCC, 0x94, 0xC9, 0x84, 0xCF,
-	0x89, 0xCD, 0x82, 0xC9, 0x86, 0xCE, 0x91, 0xCC,
-	0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0x91, 0xCC,
-	0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0x91, 0xCC,
-	0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0x91, 0xCC,
+	0xA9, 0xCC, 0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0xA9, 0xCC, 0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0xA9, 0xCC, 0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0xA9, 0xCC, 0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0xB1, 0xCC, 0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0xB1, 0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0xB1, 0xCC, 0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0xB1, 0xCC, 0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
 	// Bytes 4940 - 497f
-	0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0x91, 0xCC,
-	0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0x91, 0xCC,
-	0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0x97, 0xCC,
-	0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0x97, 0xCC,
-	0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0x97, 0xCC,
-	0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0x97, 0xCC,
-	0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0x97, 0xCC,
-	0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0x97, 0xCC,
+	0xB1, 0xCC, 0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0xB1, 0xCC, 0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0xB7, 0xCC, 0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0xB7, 0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0xB7, 0xCC, 0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE,
+	0xB7, 0xCC, 0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE,
+	0xB7, 0xCC, 0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE,
+	0xB7, 0xCC, 0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCF,
 	// Bytes 4980 - 49bf
-	0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0xA9, 0xCC,
-	0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0xA9, 0xCC,
-	0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0xA9, 0xCC,
-	0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0xA9, 0xCC,
-	0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0xA9, 0xCC,
-	0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0xA9, 0xCC,
-	0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0xB1, 0xCC,
-	0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0xB1, 0xCC,
+	0x89, 0xCC, 0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCF,
+	0x89, 0xCC, 0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCF,
+	0x89, 0xCC, 0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCF,
+	0x89, 0xCC, 0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCF,
+	0x89, 0xCC, 0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCF,
+	0x89, 0xCC, 0x94, 0xCD, 0x82, 0xCA, 0x42, 0xCC,
+	0x80, 0xC9, 0x32, 0x42, 0xCC, 0x81, 0xC9, 0x32,
+	0x42, 0xCC, 0x93, 0xC9, 0x32, 0x43, 0xE1, 0x85,
 	// Bytes 49c0 - 49ff
-	0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0xB1, 0xCC,
-	0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0xB1, 0xCC,
-	0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0xB1, 0xCC,
-	0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0xB1, 0xCC,
-	0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0xB7, 0xCC,
-	0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0xB7, 0xCC,
-	0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0xB7, 0xCC,
-	0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCE, 0xB7, 0xCC,
+	0xA1, 0x01, 0x00, 0x43, 0xE1, 0x85, 0xA2, 0x01,
+	0x00, 0x43, 0xE1, 0x85, 0xA3, 0x01, 0x00, 0x43,
+	0xE1, 0x85, 0xA4, 0x01, 0x00, 0x43, 0xE1, 0x85,
+	0xA5, 0x01, 0x00, 0x43, 0xE1, 0x85, 0xA6, 0x01,
+	0x00, 0x43, 0xE1, 0x85, 0xA7, 0x01, 0x00, 0x43,
+	0xE1, 0x85, 0xA8, 0x01, 0x00, 0x43, 0xE1, 0x85,
+	0xA9, 0x01, 0x00, 0x43, 0xE1, 0x85, 0xAA, 0x01,
+	0x00, 0x43, 0xE1, 0x85, 0xAB, 0x01, 0x00, 0x43,
 	// Bytes 4a00 - 4a3f
-	0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCE, 0xB7, 0xCC,
-	0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCE, 0xB7, 0xCC,
-	0x94, 0xCD, 0x82, 0xCA, 0x86, 0xCF, 0x89, 0xCC,
-	0x93, 0xCC, 0x80, 0xCA, 0x86, 0xCF, 0x89, 0xCC,
-	0x93, 0xCC, 0x81, 0xCA, 0x86, 0xCF, 0x89, 0xCC,
-	0x93, 0xCD, 0x82, 0xCA, 0x86, 0xCF, 0x89, 0xCC,
-	0x94, 0xCC, 0x80, 0xCA, 0x86, 0xCF, 0x89, 0xCC,
-	0x94, 0xCC, 0x81, 0xCA, 0x86, 0xCF, 0x89, 0xCC,
+	0xE1, 0x85, 0xAC, 0x01, 0x00, 0x43, 0xE1, 0x85,
+	0xAD, 0x01, 0x00, 0x43, 0xE1, 0x85, 0xAE, 0x01,
+	0x00, 0x43, 0xE1, 0x85, 0xAF, 0x01, 0x00, 0x43,
+	0xE1, 0x85, 0xB0, 0x01, 0x00, 0x43, 0xE1, 0x85,
+	0xB1, 0x01, 0x00, 0x43, 0xE1, 0x85, 0xB2, 0x01,
+	0x00, 0x43, 0xE1, 0x85, 0xB3, 0x01, 0x00, 0x43,
+	0xE1, 0x85, 0xB4, 0x01, 0x00, 0x43, 0xE1, 0x85,
+	0xB5, 0x01, 0x00, 0x43, 0xE1, 0x86, 0xAA, 0x01,
 	// Bytes 4a40 - 4a7f
-	0x94, 0xCD, 0x82, 0xCA, 0x42, 0xCC, 0x80, 0xC9,
-	0x32, 0x42, 0xCC, 0x81, 0xC9, 0x32, 0x42, 0xCC,
-	0x93, 0xC9, 0x32, 0x44, 0xCC, 0x88, 0xCC, 0x81,
-	0xCA, 0x32, 0x43, 0xE3, 0x82, 0x99, 0x0D, 0x03,
-	0x43, 0xE3, 0x82, 0x9A, 0x0D, 0x03, 0x46, 0xE0,
-	0xBD, 0xB1, 0xE0, 0xBD, 0xB2, 0x9E, 0x26, 0x46,
-	0xE0, 0xBD, 0xB1, 0xE0, 0xBD, 0xB4, 0xA2, 0x26,
-	0x46, 0xE0, 0xBD, 0xB1, 0xE0, 0xBE, 0x80, 0x9E,
+	0x00, 0x43, 0xE1, 0x86, 0xAC, 0x01, 0x00, 0x43,
+	0xE1, 0x86, 0xAD, 0x01, 0x00, 0x43, 0xE1, 0x86,
+	0xB0, 0x01, 0x00, 0x43, 0xE1, 0x86, 0xB1, 0x01,
+	0x00, 0x43, 0xE1, 0x86, 0xB2, 0x01, 0x00, 0x43,
+	0xE1, 0x86, 0xB3, 0x01, 0x00, 0x43, 0xE1, 0x86,
+	0xB4, 0x01, 0x00, 0x43, 0xE1, 0x86, 0xB5, 0x01,
+	0x00, 0x44, 0xCC, 0x88, 0xCC, 0x81, 0xCA, 0x32,
+	0x43, 0xE3, 0x82, 0x99, 0x0D, 0x03, 0x43, 0xE3,
 	// Bytes 4a80 - 4abf
-	0x26, 0x00, 0x01,
+	0x82, 0x9A, 0x0D, 0x03, 0x46, 0xE0, 0xBD, 0xB1,
+	0xE0, 0xBD, 0xB2, 0x9E, 0x26, 0x46, 0xE0, 0xBD,
+	0xB1, 0xE0, 0xBD, 0xB4, 0xA2, 0x26, 0x46, 0xE0,
+	0xBD, 0xB1, 0xE0, 0xBE, 0x80, 0x9E, 0x26, 0x00,
+	0x01,
 }
 
 // lookup returns the trie value for the first UTF-8 encoding in s and
@@ -2892,7 +2898,7 @@
 	return 0
 }
 
-// nfcTrie. Total size: 10332 bytes (10.09 KiB). Checksum: ad355b768fddb1b6.
+// nfcTrie. Total size: 10332 bytes (10.09 KiB). Checksum: 51cc525b297fc970.
 type nfcTrie struct{}
 
 func newNfcTrie(i int) *nfcTrie {
@@ -2928,22 +2934,22 @@
 	0x76: 0xa000, 0x77: 0xa000, 0x78: 0xa000, 0x79: 0xa000, 0x7a: 0xa000,
 	// Block 0x2, offset 0x80
 	// Block 0x3, offset 0xc0
-	0xc0: 0x2f6f, 0xc1: 0x2f74, 0xc2: 0x471e, 0xc3: 0x2f79, 0xc4: 0x472d, 0xc5: 0x4732,
-	0xc6: 0xa000, 0xc7: 0x473c, 0xc8: 0x2fe2, 0xc9: 0x2fe7, 0xca: 0x4741, 0xcb: 0x2ffb,
-	0xcc: 0x306e, 0xcd: 0x3073, 0xce: 0x3078, 0xcf: 0x4755, 0xd1: 0x3104,
-	0xd2: 0x3127, 0xd3: 0x312c, 0xd4: 0x475f, 0xd5: 0x4764, 0xd6: 0x4773,
-	0xd8: 0xa000, 0xd9: 0x31b3, 0xda: 0x31b8, 0xdb: 0x31bd, 0xdc: 0x47a5, 0xdd: 0x3235,
-	0xe0: 0x327b, 0xe1: 0x3280, 0xe2: 0x47af, 0xe3: 0x3285,
-	0xe4: 0x47be, 0xe5: 0x47c3, 0xe6: 0xa000, 0xe7: 0x47cd, 0xe8: 0x32ee, 0xe9: 0x32f3,
-	0xea: 0x47d2, 0xeb: 0x3307, 0xec: 0x337f, 0xed: 0x3384, 0xee: 0x3389, 0xef: 0x47e6,
-	0xf1: 0x3415, 0xf2: 0x3438, 0xf3: 0x343d, 0xf4: 0x47f0, 0xf5: 0x47f5,
-	0xf6: 0x4804, 0xf8: 0xa000, 0xf9: 0x34c9, 0xfa: 0x34ce, 0xfb: 0x34d3,
-	0xfc: 0x4836, 0xfd: 0x3550, 0xff: 0x3569,
+	0xc0: 0x2f6f, 0xc1: 0x2f74, 0xc2: 0x4688, 0xc3: 0x2f79, 0xc4: 0x4697, 0xc5: 0x469c,
+	0xc6: 0xa000, 0xc7: 0x46a6, 0xc8: 0x2fe2, 0xc9: 0x2fe7, 0xca: 0x46ab, 0xcb: 0x2ffb,
+	0xcc: 0x306e, 0xcd: 0x3073, 0xce: 0x3078, 0xcf: 0x46bf, 0xd1: 0x3104,
+	0xd2: 0x3127, 0xd3: 0x312c, 0xd4: 0x46c9, 0xd5: 0x46ce, 0xd6: 0x46dd,
+	0xd8: 0xa000, 0xd9: 0x31b3, 0xda: 0x31b8, 0xdb: 0x31bd, 0xdc: 0x470f, 0xdd: 0x3235,
+	0xe0: 0x327b, 0xe1: 0x3280, 0xe2: 0x4719, 0xe3: 0x3285,
+	0xe4: 0x4728, 0xe5: 0x472d, 0xe6: 0xa000, 0xe7: 0x4737, 0xe8: 0x32ee, 0xe9: 0x32f3,
+	0xea: 0x473c, 0xeb: 0x3307, 0xec: 0x337f, 0xed: 0x3384, 0xee: 0x3389, 0xef: 0x4750,
+	0xf1: 0x3415, 0xf2: 0x3438, 0xf3: 0x343d, 0xf4: 0x475a, 0xf5: 0x475f,
+	0xf6: 0x476e, 0xf8: 0xa000, 0xf9: 0x34c9, 0xfa: 0x34ce, 0xfb: 0x34d3,
+	0xfc: 0x47a0, 0xfd: 0x3550, 0xff: 0x3569,
 	// Block 0x4, offset 0x100
-	0x100: 0x2f7e, 0x101: 0x328a, 0x102: 0x4723, 0x103: 0x47b4, 0x104: 0x2f9c, 0x105: 0x32a8,
+	0x100: 0x2f7e, 0x101: 0x328a, 0x102: 0x468d, 0x103: 0x471e, 0x104: 0x2f9c, 0x105: 0x32a8,
 	0x106: 0x2fb0, 0x107: 0x32bc, 0x108: 0x2fb5, 0x109: 0x32c1, 0x10a: 0x2fba, 0x10b: 0x32c6,
 	0x10c: 0x2fbf, 0x10d: 0x32cb, 0x10e: 0x2fc9, 0x10f: 0x32d5,
-	0x112: 0x4746, 0x113: 0x47d7, 0x114: 0x2ff1, 0x115: 0x32fd, 0x116: 0x2ff6, 0x117: 0x3302,
+	0x112: 0x46b0, 0x113: 0x4741, 0x114: 0x2ff1, 0x115: 0x32fd, 0x116: 0x2ff6, 0x117: 0x3302,
 	0x118: 0x3014, 0x119: 0x3320, 0x11a: 0x3005, 0x11b: 0x3311, 0x11c: 0x302d, 0x11d: 0x3339,
 	0x11e: 0x3037, 0x11f: 0x3343, 0x120: 0x303c, 0x121: 0x3348, 0x122: 0x3046, 0x123: 0x3352,
 	0x124: 0x304b, 0x125: 0x3357, 0x128: 0x307d, 0x129: 0x338e,
@@ -2954,12 +2960,12 @@
 	// Block 0x5, offset 0x140
 	0x143: 0x30ff, 0x144: 0x3410, 0x145: 0x3118,
 	0x146: 0x3429, 0x147: 0x310e, 0x148: 0x341f,
-	0x14c: 0x4769, 0x14d: 0x47fa, 0x14e: 0x3131, 0x14f: 0x3442, 0x150: 0x313b, 0x151: 0x344c,
+	0x14c: 0x46d3, 0x14d: 0x4764, 0x14e: 0x3131, 0x14f: 0x3442, 0x150: 0x313b, 0x151: 0x344c,
 	0x154: 0x3159, 0x155: 0x346a, 0x156: 0x3172, 0x157: 0x3483,
-	0x158: 0x3163, 0x159: 0x3474, 0x15a: 0x478c, 0x15b: 0x481d, 0x15c: 0x317c, 0x15d: 0x348d,
-	0x15e: 0x318b, 0x15f: 0x349c, 0x160: 0x4791, 0x161: 0x4822, 0x162: 0x31a4, 0x163: 0x34ba,
-	0x164: 0x3195, 0x165: 0x34ab, 0x168: 0x479b, 0x169: 0x482c,
-	0x16a: 0x47a0, 0x16b: 0x4831, 0x16c: 0x31c2, 0x16d: 0x34d8, 0x16e: 0x31cc, 0x16f: 0x34e2,
+	0x158: 0x3163, 0x159: 0x3474, 0x15a: 0x46f6, 0x15b: 0x4787, 0x15c: 0x317c, 0x15d: 0x348d,
+	0x15e: 0x318b, 0x15f: 0x349c, 0x160: 0x46fb, 0x161: 0x478c, 0x162: 0x31a4, 0x163: 0x34ba,
+	0x164: 0x3195, 0x165: 0x34ab, 0x168: 0x4705, 0x169: 0x4796,
+	0x16a: 0x470a, 0x16b: 0x479b, 0x16c: 0x31c2, 0x16d: 0x34d8, 0x16e: 0x31cc, 0x16f: 0x34e2,
 	0x170: 0x31d1, 0x171: 0x34e7, 0x172: 0x31ef, 0x173: 0x3505, 0x174: 0x3212, 0x175: 0x3528,
 	0x176: 0x323a, 0x177: 0x3555, 0x178: 0x324e, 0x179: 0x325d, 0x17a: 0x357d, 0x17b: 0x3267,
 	0x17c: 0x3587, 0x17d: 0x326c, 0x17e: 0x358c, 0x17f: 0xa000,
@@ -2971,7 +2977,7 @@
 	0x198: 0x3b57, 0x199: 0x39d6, 0x19a: 0x3b65, 0x19b: 0x39c1, 0x19c: 0x3b50,
 	0x19e: 0x38b0, 0x19f: 0x3a3f, 0x1a0: 0x38a9, 0x1a1: 0x3a38, 0x1a2: 0x35b3, 0x1a3: 0x35c5,
 	0x1a6: 0x3041, 0x1a7: 0x334d, 0x1a8: 0x30be, 0x1a9: 0x33cf,
-	0x1aa: 0x4782, 0x1ab: 0x4813, 0x1ac: 0x3990, 0x1ad: 0x3b1f, 0x1ae: 0x35d7, 0x1af: 0x35dd,
+	0x1aa: 0x46ec, 0x1ab: 0x477d, 0x1ac: 0x3990, 0x1ad: 0x3b1f, 0x1ae: 0x35d7, 0x1af: 0x35dd,
 	0x1b0: 0x33c5, 0x1b4: 0x3028, 0x1b5: 0x3334,
 	0x1b8: 0x30fa, 0x1b9: 0x340b, 0x1ba: 0x38b7, 0x1bb: 0x3a46,
 	0x1bc: 0x35ad, 0x1bd: 0x35bf, 0x1be: 0x35b9, 0x1bf: 0x35cb,
@@ -2982,8 +2988,8 @@
 	0x1d2: 0x316d, 0x1d3: 0x347e, 0x1d4: 0x31db, 0x1d5: 0x34f1, 0x1d6: 0x31e0, 0x1d7: 0x34f6,
 	0x1d8: 0x3186, 0x1d9: 0x3497, 0x1da: 0x319f, 0x1db: 0x34b5,
 	0x1de: 0x305a, 0x1df: 0x3366,
-	0x1e6: 0x4728, 0x1e7: 0x47b9, 0x1e8: 0x4750, 0x1e9: 0x47e1,
-	0x1ea: 0x395f, 0x1eb: 0x3aee, 0x1ec: 0x393c, 0x1ed: 0x3acb, 0x1ee: 0x476e, 0x1ef: 0x47ff,
+	0x1e6: 0x4692, 0x1e7: 0x4723, 0x1e8: 0x46ba, 0x1e9: 0x474b,
+	0x1ea: 0x395f, 0x1eb: 0x3aee, 0x1ec: 0x393c, 0x1ed: 0x3acb, 0x1ee: 0x46d8, 0x1ef: 0x4769,
 	0x1f0: 0x3958, 0x1f1: 0x3ae7, 0x1f2: 0x3244, 0x1f3: 0x355f,
 	// Block 0x8, offset 0x200
 	0x200: 0x9932, 0x201: 0x9932, 0x202: 0x9932, 0x203: 0x9932, 0x204: 0x9932, 0x205: 0x8132,
@@ -2998,7 +3004,7 @@
 	0x236: 0x8101, 0x237: 0x8101, 0x238: 0x9901, 0x239: 0x812d, 0x23a: 0x812d, 0x23b: 0x812d,
 	0x23c: 0x812d, 0x23d: 0x8132, 0x23e: 0x8132, 0x23f: 0x8132,
 	// Block 0x9, offset 0x240
-	0x240: 0x4a44, 0x241: 0x4a49, 0x242: 0x9932, 0x243: 0x4a4e, 0x244: 0x4a53, 0x245: 0x9936,
+	0x240: 0x49ae, 0x241: 0x49b3, 0x242: 0x9932, 0x243: 0x49b8, 0x244: 0x4a71, 0x245: 0x9936,
 	0x246: 0x8132, 0x247: 0x812d, 0x248: 0x812d, 0x249: 0x812d, 0x24a: 0x8132, 0x24b: 0x8132,
 	0x24c: 0x8132, 0x24d: 0x812d, 0x24e: 0x812d, 0x250: 0x8132, 0x251: 0x8132,
 	0x252: 0x8132, 0x253: 0x812d, 0x254: 0x812d, 0x255: 0x812d, 0x256: 0x812d, 0x257: 0x8132,
@@ -3017,7 +3023,7 @@
 	0x299: 0xa000,
 	0x29f: 0xa000, 0x2a1: 0xa000,
 	0x2a5: 0xa000, 0x2a9: 0xa000,
-	0x2aa: 0x3637, 0x2ab: 0x3667, 0x2ac: 0x4894, 0x2ad: 0x3697, 0x2ae: 0x48be, 0x2af: 0x36a9,
+	0x2aa: 0x3637, 0x2ab: 0x3667, 0x2ac: 0x47fe, 0x2ad: 0x3697, 0x2ae: 0x4828, 0x2af: 0x36a9,
 	0x2b0: 0x3e70, 0x2b1: 0xa000, 0x2b5: 0xa000,
 	0x2b7: 0xa000, 0x2b9: 0xa000,
 	0x2bf: 0xa000,
@@ -3078,15 +3084,15 @@
 	0x424: 0x305f, 0x425: 0x336b, 0x426: 0x3055, 0x427: 0x3361, 0x428: 0x3064, 0x429: 0x3370,
 	0x42a: 0x3069, 0x42b: 0x3375, 0x42c: 0x30af, 0x42d: 0x33bb, 0x42e: 0x390b, 0x42f: 0x3a9a,
 	0x430: 0x30b9, 0x431: 0x33ca, 0x432: 0x30c3, 0x433: 0x33d4, 0x434: 0x30cd, 0x435: 0x33de,
-	0x436: 0x475a, 0x437: 0x47eb, 0x438: 0x3912, 0x439: 0x3aa1, 0x43a: 0x30e6, 0x43b: 0x33f7,
+	0x436: 0x46c4, 0x437: 0x4755, 0x438: 0x3912, 0x439: 0x3aa1, 0x43a: 0x30e6, 0x43b: 0x33f7,
 	0x43c: 0x30e1, 0x43d: 0x33f2, 0x43e: 0x30eb, 0x43f: 0x33fc,
 	// Block 0x11, offset 0x440
 	0x440: 0x30f0, 0x441: 0x3401, 0x442: 0x30f5, 0x443: 0x3406, 0x444: 0x3109, 0x445: 0x341a,
 	0x446: 0x3113, 0x447: 0x3424, 0x448: 0x3122, 0x449: 0x3433, 0x44a: 0x311d, 0x44b: 0x342e,
 	0x44c: 0x3935, 0x44d: 0x3ac4, 0x44e: 0x3943, 0x44f: 0x3ad2, 0x450: 0x394a, 0x451: 0x3ad9,
 	0x452: 0x3951, 0x453: 0x3ae0, 0x454: 0x314f, 0x455: 0x3460, 0x456: 0x3154, 0x457: 0x3465,
-	0x458: 0x315e, 0x459: 0x346f, 0x45a: 0x4787, 0x45b: 0x4818, 0x45c: 0x3997, 0x45d: 0x3b26,
-	0x45e: 0x3177, 0x45f: 0x3488, 0x460: 0x3181, 0x461: 0x3492, 0x462: 0x4796, 0x463: 0x4827,
+	0x458: 0x315e, 0x459: 0x346f, 0x45a: 0x46f1, 0x45b: 0x4782, 0x45c: 0x3997, 0x45d: 0x3b26,
+	0x45e: 0x3177, 0x45f: 0x3488, 0x460: 0x3181, 0x461: 0x3492, 0x462: 0x4700, 0x463: 0x4791,
 	0x464: 0x399e, 0x465: 0x3b2d, 0x466: 0x39a5, 0x467: 0x3b34, 0x468: 0x39ac, 0x469: 0x3b3b,
 	0x46a: 0x3190, 0x46b: 0x34a1, 0x46c: 0x319a, 0x46d: 0x34b0, 0x46e: 0x31ae, 0x46f: 0x34c4,
 	0x470: 0x31a9, 0x471: 0x34bf, 0x472: 0x31ea, 0x473: 0x3500, 0x474: 0x31f9, 0x475: 0x350f,
@@ -3098,16 +3104,16 @@
 	0x48c: 0x322b, 0x48d: 0x3546, 0x48e: 0x3249, 0x48f: 0x3564, 0x490: 0x3262, 0x491: 0x3582,
 	0x492: 0x3271, 0x493: 0x3591, 0x494: 0x3276, 0x495: 0x3596, 0x496: 0x337a, 0x497: 0x34a6,
 	0x498: 0x3537, 0x499: 0x3573, 0x49b: 0x35d1,
-	0x4a0: 0x4737, 0x4a1: 0x47c8, 0x4a2: 0x2f83, 0x4a3: 0x328f,
+	0x4a0: 0x46a1, 0x4a1: 0x4732, 0x4a2: 0x2f83, 0x4a3: 0x328f,
 	0x4a4: 0x3878, 0x4a5: 0x3a07, 0x4a6: 0x3871, 0x4a7: 0x3a00, 0x4a8: 0x3886, 0x4a9: 0x3a15,
 	0x4aa: 0x387f, 0x4ab: 0x3a0e, 0x4ac: 0x38be, 0x4ad: 0x3a4d, 0x4ae: 0x3894, 0x4af: 0x3a23,
 	0x4b0: 0x388d, 0x4b1: 0x3a1c, 0x4b2: 0x38a2, 0x4b3: 0x3a31, 0x4b4: 0x389b, 0x4b5: 0x3a2a,
-	0x4b6: 0x38c5, 0x4b7: 0x3a54, 0x4b8: 0x474b, 0x4b9: 0x47dc, 0x4ba: 0x3000, 0x4bb: 0x330c,
+	0x4b6: 0x38c5, 0x4b7: 0x3a54, 0x4b8: 0x46b5, 0x4b9: 0x4746, 0x4ba: 0x3000, 0x4bb: 0x330c,
 	0x4bc: 0x2fec, 0x4bd: 0x32f8, 0x4be: 0x38da, 0x4bf: 0x3a69,
 	// Block 0x13, offset 0x4c0
 	0x4c0: 0x38d3, 0x4c1: 0x3a62, 0x4c2: 0x38e8, 0x4c3: 0x3a77, 0x4c4: 0x38e1, 0x4c5: 0x3a70,
 	0x4c6: 0x38fd, 0x4c7: 0x3a8c, 0x4c8: 0x3091, 0x4c9: 0x339d, 0x4ca: 0x30a5, 0x4cb: 0x33b1,
-	0x4cc: 0x477d, 0x4cd: 0x480e, 0x4ce: 0x3136, 0x4cf: 0x3447, 0x4d0: 0x3920, 0x4d1: 0x3aaf,
+	0x4cc: 0x46e7, 0x4cd: 0x4778, 0x4ce: 0x3136, 0x4cf: 0x3447, 0x4d0: 0x3920, 0x4d1: 0x3aaf,
 	0x4d2: 0x3919, 0x4d3: 0x3aa8, 0x4d4: 0x392e, 0x4d5: 0x3abd, 0x4d6: 0x3927, 0x4d7: 0x3ab6,
 	0x4d8: 0x3989, 0x4d9: 0x3b18, 0x4da: 0x396d, 0x4db: 0x3afc, 0x4dc: 0x3966, 0x4dd: 0x3af5,
 	0x4de: 0x397b, 0x4df: 0x3b0a, 0x4e0: 0x3974, 0x4e1: 0x3b03, 0x4e2: 0x3982, 0x4e3: 0x3b11,
@@ -3116,29 +3122,29 @@
 	0x4f0: 0x39f9, 0x4f1: 0x3b88, 0x4f2: 0x3230, 0x4f3: 0x354b, 0x4f4: 0x3258, 0x4f5: 0x3578,
 	0x4f6: 0x3253, 0x4f7: 0x356e, 0x4f8: 0x323f, 0x4f9: 0x355a,
 	// Block 0x14, offset 0x500
-	0x500: 0x489a, 0x501: 0x48a0, 0x502: 0x49b4, 0x503: 0x49cc, 0x504: 0x49bc, 0x505: 0x49d4,
-	0x506: 0x49c4, 0x507: 0x49dc, 0x508: 0x4840, 0x509: 0x4846, 0x50a: 0x4924, 0x50b: 0x493c,
-	0x50c: 0x492c, 0x50d: 0x4944, 0x50e: 0x4934, 0x50f: 0x494c, 0x510: 0x48ac, 0x511: 0x48b2,
+	0x500: 0x4804, 0x501: 0x480a, 0x502: 0x491e, 0x503: 0x4936, 0x504: 0x4926, 0x505: 0x493e,
+	0x506: 0x492e, 0x507: 0x4946, 0x508: 0x47aa, 0x509: 0x47b0, 0x50a: 0x488e, 0x50b: 0x48a6,
+	0x50c: 0x4896, 0x50d: 0x48ae, 0x50e: 0x489e, 0x50f: 0x48b6, 0x510: 0x4816, 0x511: 0x481c,
 	0x512: 0x3db8, 0x513: 0x3dc8, 0x514: 0x3dc0, 0x515: 0x3dd0,
-	0x518: 0x484c, 0x519: 0x4852, 0x51a: 0x3ce8, 0x51b: 0x3cf8, 0x51c: 0x3cf0, 0x51d: 0x3d00,
-	0x520: 0x48c4, 0x521: 0x48ca, 0x522: 0x49e4, 0x523: 0x49fc,
-	0x524: 0x49ec, 0x525: 0x4a04, 0x526: 0x49f4, 0x527: 0x4a0c, 0x528: 0x4858, 0x529: 0x485e,
-	0x52a: 0x4954, 0x52b: 0x496c, 0x52c: 0x495c, 0x52d: 0x4974, 0x52e: 0x4964, 0x52f: 0x497c,
-	0x530: 0x48dc, 0x531: 0x48e2, 0x532: 0x3e18, 0x533: 0x3e30, 0x534: 0x3e20, 0x535: 0x3e38,
-	0x536: 0x3e28, 0x537: 0x3e40, 0x538: 0x4864, 0x539: 0x486a, 0x53a: 0x3d18, 0x53b: 0x3d30,
+	0x518: 0x47b6, 0x519: 0x47bc, 0x51a: 0x3ce8, 0x51b: 0x3cf8, 0x51c: 0x3cf0, 0x51d: 0x3d00,
+	0x520: 0x482e, 0x521: 0x4834, 0x522: 0x494e, 0x523: 0x4966,
+	0x524: 0x4956, 0x525: 0x496e, 0x526: 0x495e, 0x527: 0x4976, 0x528: 0x47c2, 0x529: 0x47c8,
+	0x52a: 0x48be, 0x52b: 0x48d6, 0x52c: 0x48c6, 0x52d: 0x48de, 0x52e: 0x48ce, 0x52f: 0x48e6,
+	0x530: 0x4846, 0x531: 0x484c, 0x532: 0x3e18, 0x533: 0x3e30, 0x534: 0x3e20, 0x535: 0x3e38,
+	0x536: 0x3e28, 0x537: 0x3e40, 0x538: 0x47ce, 0x539: 0x47d4, 0x53a: 0x3d18, 0x53b: 0x3d30,
 	0x53c: 0x3d20, 0x53d: 0x3d38, 0x53e: 0x3d28, 0x53f: 0x3d40,
 	// Block 0x15, offset 0x540
-	0x540: 0x48e8, 0x541: 0x48ee, 0x542: 0x3e48, 0x543: 0x3e58, 0x544: 0x3e50, 0x545: 0x3e60,
-	0x548: 0x4870, 0x549: 0x4876, 0x54a: 0x3d48, 0x54b: 0x3d58,
-	0x54c: 0x3d50, 0x54d: 0x3d60, 0x550: 0x48fa, 0x551: 0x4900,
+	0x540: 0x4852, 0x541: 0x4858, 0x542: 0x3e48, 0x543: 0x3e58, 0x544: 0x3e50, 0x545: 0x3e60,
+	0x548: 0x47da, 0x549: 0x47e0, 0x54a: 0x3d48, 0x54b: 0x3d58,
+	0x54c: 0x3d50, 0x54d: 0x3d60, 0x550: 0x4864, 0x551: 0x486a,
 	0x552: 0x3e80, 0x553: 0x3e98, 0x554: 0x3e88, 0x555: 0x3ea0, 0x556: 0x3e90, 0x557: 0x3ea8,
-	0x559: 0x487c, 0x55b: 0x3d68, 0x55d: 0x3d70,
-	0x55f: 0x3d78, 0x560: 0x4912, 0x561: 0x4918, 0x562: 0x4a14, 0x563: 0x4a2c,
-	0x564: 0x4a1c, 0x565: 0x4a34, 0x566: 0x4a24, 0x567: 0x4a3c, 0x568: 0x4882, 0x569: 0x4888,
-	0x56a: 0x4984, 0x56b: 0x499c, 0x56c: 0x498c, 0x56d: 0x49a4, 0x56e: 0x4994, 0x56f: 0x49ac,
-	0x570: 0x488e, 0x571: 0x43b4, 0x572: 0x3691, 0x573: 0x43ba, 0x574: 0x48b8, 0x575: 0x43c0,
-	0x576: 0x36a3, 0x577: 0x43c6, 0x578: 0x36c1, 0x579: 0x43cc, 0x57a: 0x36d9, 0x57b: 0x43d2,
-	0x57c: 0x4906, 0x57d: 0x43d8,
+	0x559: 0x47e6, 0x55b: 0x3d68, 0x55d: 0x3d70,
+	0x55f: 0x3d78, 0x560: 0x487c, 0x561: 0x4882, 0x562: 0x497e, 0x563: 0x4996,
+	0x564: 0x4986, 0x565: 0x499e, 0x566: 0x498e, 0x567: 0x49a6, 0x568: 0x47ec, 0x569: 0x47f2,
+	0x56a: 0x48ee, 0x56b: 0x4906, 0x56c: 0x48f6, 0x56d: 0x490e, 0x56e: 0x48fe, 0x56f: 0x4916,
+	0x570: 0x47f8, 0x571: 0x431e, 0x572: 0x3691, 0x573: 0x4324, 0x574: 0x4822, 0x575: 0x432a,
+	0x576: 0x36a3, 0x577: 0x4330, 0x578: 0x36c1, 0x579: 0x4336, 0x57a: 0x36d9, 0x57b: 0x433c,
+	0x57c: 0x4870, 0x57d: 0x4342,
 	// Block 0x16, offset 0x580
 	0x580: 0x3da0, 0x581: 0x3da8, 0x582: 0x4184, 0x583: 0x41a2, 0x584: 0x418e, 0x585: 0x41ac,
 	0x586: 0x4198, 0x587: 0x41b6, 0x588: 0x3cd8, 0x589: 0x3ce0, 0x58a: 0x40d0, 0x58b: 0x40ee,
@@ -3149,19 +3155,19 @@
 	0x5a4: 0x4206, 0x5a5: 0x4224, 0x5a6: 0x4210, 0x5a7: 0x422e, 0x5a8: 0x3d80, 0x5a9: 0x3d88,
 	0x5aa: 0x4148, 0x5ab: 0x4166, 0x5ac: 0x4152, 0x5ad: 0x4170, 0x5ae: 0x415c, 0x5af: 0x417a,
 	0x5b0: 0x3685, 0x5b1: 0x367f, 0x5b2: 0x3d90, 0x5b3: 0x368b, 0x5b4: 0x3d98,
-	0x5b6: 0x48a6, 0x5b7: 0x3db0, 0x5b8: 0x35f5, 0x5b9: 0x35ef, 0x5ba: 0x35e3, 0x5bb: 0x4384,
+	0x5b6: 0x4810, 0x5b7: 0x3db0, 0x5b8: 0x35f5, 0x5b9: 0x35ef, 0x5ba: 0x35e3, 0x5bb: 0x42ee,
 	0x5bc: 0x35fb, 0x5bd: 0x8100, 0x5be: 0x01d3, 0x5bf: 0xa100,
 	// Block 0x17, offset 0x5c0
 	0x5c0: 0x8100, 0x5c1: 0x35a7, 0x5c2: 0x3dd8, 0x5c3: 0x369d, 0x5c4: 0x3de0,
-	0x5c6: 0x48d0, 0x5c7: 0x3df8, 0x5c8: 0x3601, 0x5c9: 0x438a, 0x5ca: 0x360d, 0x5cb: 0x4390,
+	0x5c6: 0x483a, 0x5c7: 0x3df8, 0x5c8: 0x3601, 0x5c9: 0x42f4, 0x5ca: 0x360d, 0x5cb: 0x42fa,
 	0x5cc: 0x3619, 0x5cd: 0x3b8f, 0x5ce: 0x3b96, 0x5cf: 0x3b9d, 0x5d0: 0x36b5, 0x5d1: 0x36af,
-	0x5d2: 0x3e00, 0x5d3: 0x457a, 0x5d6: 0x36bb, 0x5d7: 0x3e10,
-	0x5d8: 0x3631, 0x5d9: 0x362b, 0x5da: 0x361f, 0x5db: 0x4396, 0x5dd: 0x3ba4,
-	0x5de: 0x3bab, 0x5df: 0x3bb2, 0x5e0: 0x36eb, 0x5e1: 0x36e5, 0x5e2: 0x3e68, 0x5e3: 0x4582,
+	0x5d2: 0x3e00, 0x5d3: 0x44e4, 0x5d6: 0x36bb, 0x5d7: 0x3e10,
+	0x5d8: 0x3631, 0x5d9: 0x362b, 0x5da: 0x361f, 0x5db: 0x4300, 0x5dd: 0x3ba4,
+	0x5de: 0x3bab, 0x5df: 0x3bb2, 0x5e0: 0x36eb, 0x5e1: 0x36e5, 0x5e2: 0x3e68, 0x5e3: 0x44ec,
 	0x5e4: 0x36cd, 0x5e5: 0x36d3, 0x5e6: 0x36f1, 0x5e7: 0x3e78, 0x5e8: 0x3661, 0x5e9: 0x365b,
-	0x5ea: 0x364f, 0x5eb: 0x43a2, 0x5ec: 0x3649, 0x5ed: 0x359b, 0x5ee: 0x437e, 0x5ef: 0x0081,
+	0x5ea: 0x364f, 0x5eb: 0x430c, 0x5ec: 0x3649, 0x5ed: 0x359b, 0x5ee: 0x42e8, 0x5ef: 0x0081,
 	0x5f2: 0x3eb0, 0x5f3: 0x36f7, 0x5f4: 0x3eb8,
-	0x5f6: 0x491e, 0x5f7: 0x3ed0, 0x5f8: 0x363d, 0x5f9: 0x439c, 0x5fa: 0x366d, 0x5fb: 0x43ae,
+	0x5f6: 0x4888, 0x5f7: 0x3ed0, 0x5f8: 0x363d, 0x5f9: 0x4306, 0x5fa: 0x366d, 0x5fb: 0x4318,
 	0x5fc: 0x3679, 0x5fd: 0x4256, 0x5fe: 0xa100,
 	// Block 0x18, offset 0x600
 	0x601: 0x3c06, 0x603: 0xa000, 0x604: 0x3c0d, 0x605: 0xa000,
@@ -3519,8 +3525,8 @@
 	{value: 0x8100, lo: 0xb8, hi: 0xb8},
 	// Block 0x1, offset 0x5
 	{value: 0x0091, lo: 0x03},
-	{value: 0x4778, lo: 0xa0, hi: 0xa1},
-	{value: 0x47aa, lo: 0xaf, hi: 0xb0},
+	{value: 0x46e2, lo: 0xa0, hi: 0xa1},
+	{value: 0x4714, lo: 0xaf, hi: 0xb0},
 	{value: 0xa000, lo: 0xb7, hi: 0xb7},
 	// Block 0x2, offset 0x9
 	{value: 0x0000, lo: 0x01},
@@ -3533,11 +3539,11 @@
 	{value: 0xa000, lo: 0x81, hi: 0x81},
 	{value: 0xa000, lo: 0x85, hi: 0x85},
 	{value: 0xa000, lo: 0x89, hi: 0x89},
-	{value: 0x48d6, lo: 0x8a, hi: 0x8a},
-	{value: 0x48f4, lo: 0x8b, hi: 0x8b},
+	{value: 0x4840, lo: 0x8a, hi: 0x8a},
+	{value: 0x485e, lo: 0x8b, hi: 0x8b},
 	{value: 0x36c7, lo: 0x8c, hi: 0x8c},
 	{value: 0x36df, lo: 0x8d, hi: 0x8d},
-	{value: 0x490c, lo: 0x8e, hi: 0x8e},
+	{value: 0x4876, lo: 0x8e, hi: 0x8e},
 	{value: 0xa000, lo: 0x92, hi: 0x92},
 	{value: 0x36fd, lo: 0x93, hi: 0x94},
 	// Block 0x5, offset 0x18
@@ -3665,7 +3671,7 @@
 	{value: 0x812d, lo: 0x92, hi: 0x92},
 	{value: 0x8132, lo: 0x93, hi: 0x93},
 	{value: 0x8132, lo: 0x94, hi: 0x94},
-	{value: 0x45b2, lo: 0x98, hi: 0x9f},
+	{value: 0x451c, lo: 0x98, hi: 0x9f},
 	// Block 0x12, offset 0x89
 	{value: 0x0000, lo: 0x02},
 	{value: 0x8102, lo: 0xbc, hi: 0xbc},
@@ -3676,18 +3682,18 @@
 	{value: 0x2c9e, lo: 0x8b, hi: 0x8c},
 	{value: 0x8104, lo: 0x8d, hi: 0x8d},
 	{value: 0x9900, lo: 0x97, hi: 0x97},
-	{value: 0x45f2, lo: 0x9c, hi: 0x9d},
-	{value: 0x4602, lo: 0x9f, hi: 0x9f},
+	{value: 0x455c, lo: 0x9c, hi: 0x9d},
+	{value: 0x456c, lo: 0x9f, hi: 0x9f},
 	// Block 0x14, offset 0x93
 	{value: 0x0000, lo: 0x03},
-	{value: 0x462a, lo: 0xb3, hi: 0xb3},
-	{value: 0x4632, lo: 0xb6, hi: 0xb6},
+	{value: 0x4594, lo: 0xb3, hi: 0xb3},
+	{value: 0x459c, lo: 0xb6, hi: 0xb6},
 	{value: 0x8102, lo: 0xbc, hi: 0xbc},
 	// Block 0x15, offset 0x97
 	{value: 0x0008, lo: 0x03},
 	{value: 0x8104, lo: 0x8d, hi: 0x8d},
-	{value: 0x460a, lo: 0x99, hi: 0x9b},
-	{value: 0x4622, lo: 0x9e, hi: 0x9e},
+	{value: 0x4574, lo: 0x99, hi: 0x9b},
+	{value: 0x458c, lo: 0x9e, hi: 0x9e},
 	// Block 0x16, offset 0x9b
 	{value: 0x0000, lo: 0x01},
 	{value: 0x8102, lo: 0xbc, hi: 0xbc},
@@ -3702,8 +3708,8 @@
 	{value: 0x2cbe, lo: 0x8c, hi: 0x8c},
 	{value: 0x8104, lo: 0x8d, hi: 0x8d},
 	{value: 0x9900, lo: 0x96, hi: 0x97},
-	{value: 0x463a, lo: 0x9c, hi: 0x9c},
-	{value: 0x4642, lo: 0x9d, hi: 0x9d},
+	{value: 0x45a4, lo: 0x9c, hi: 0x9c},
+	{value: 0x45ac, lo: 0x9d, hi: 0x9d},
 	// Block 0x19, offset 0xa8
 	{value: 0x0000, lo: 0x03},
 	{value: 0xa000, lo: 0x92, hi: 0x92},
@@ -3787,18 +3793,18 @@
 	{value: 0x263d, lo: 0xa9, hi: 0xa9},
 	{value: 0x8126, lo: 0xb1, hi: 0xb1},
 	{value: 0x8127, lo: 0xb2, hi: 0xb2},
-	{value: 0x4a66, lo: 0xb3, hi: 0xb3},
+	{value: 0x4a84, lo: 0xb3, hi: 0xb3},
 	{value: 0x8128, lo: 0xb4, hi: 0xb4},
-	{value: 0x4a6f, lo: 0xb5, hi: 0xb5},
-	{value: 0x464a, lo: 0xb6, hi: 0xb6},
+	{value: 0x4a8d, lo: 0xb5, hi: 0xb5},
+	{value: 0x45b4, lo: 0xb6, hi: 0xb6},
 	{value: 0x8200, lo: 0xb7, hi: 0xb7},
-	{value: 0x4652, lo: 0xb8, hi: 0xb8},
+	{value: 0x45bc, lo: 0xb8, hi: 0xb8},
 	{value: 0x8200, lo: 0xb9, hi: 0xb9},
 	{value: 0x8127, lo: 0xba, hi: 0xbd},
 	// Block 0x27, offset 0xf5
 	{value: 0x0000, lo: 0x0b},
 	{value: 0x8127, lo: 0x80, hi: 0x80},
-	{value: 0x4a78, lo: 0x81, hi: 0x81},
+	{value: 0x4a96, lo: 0x81, hi: 0x81},
 	{value: 0x8132, lo: 0x82, hi: 0x83},
 	{value: 0x8104, lo: 0x84, hi: 0x84},
 	{value: 0x8132, lo: 0x86, hi: 0x87},
@@ -3975,7 +3981,7 @@
 	{value: 0x048b, lo: 0xa9, hi: 0xaa},
 	// Block 0x45, offset 0x189
 	{value: 0x0000, lo: 0x01},
-	{value: 0x4573, lo: 0x9c, hi: 0x9c},
+	{value: 0x44dd, lo: 0x9c, hi: 0x9c},
 	// Block 0x46, offset 0x18b
 	{value: 0x0000, lo: 0x01},
 	{value: 0x8132, lo: 0xaf, hi: 0xb1},
@@ -3994,12 +4000,12 @@
 	{value: 0x812f, lo: 0xae, hi: 0xaf},
 	// Block 0x4a, offset 0x197
 	{value: 0x0000, lo: 0x03},
-	{value: 0x4a81, lo: 0xb3, hi: 0xb3},
-	{value: 0x4a81, lo: 0xb5, hi: 0xb6},
-	{value: 0x4a81, lo: 0xba, hi: 0xbf},
+	{value: 0x4a9f, lo: 0xb3, hi: 0xb3},
+	{value: 0x4a9f, lo: 0xb5, hi: 0xb6},
+	{value: 0x4a9f, lo: 0xba, hi: 0xbf},
 	// Block 0x4b, offset 0x19b
 	{value: 0x0000, lo: 0x01},
-	{value: 0x4a81, lo: 0x8f, hi: 0xa3},
+	{value: 0x4a9f, lo: 0x8f, hi: 0xa3},
 	// Block 0x4c, offset 0x19d
 	{value: 0x0000, lo: 0x01},
 	{value: 0x8100, lo: 0xae, hi: 0xbe},
@@ -4119,29 +4125,29 @@
 	{value: 0xc600, lo: 0x89, hi: 0xa3},
 	// Block 0x63, offset 0x1fb
 	{value: 0x0006, lo: 0x0d},
-	{value: 0x4426, lo: 0x9d, hi: 0x9d},
+	{value: 0x4390, lo: 0x9d, hi: 0x9d},
 	{value: 0x8115, lo: 0x9e, hi: 0x9e},
-	{value: 0x4498, lo: 0x9f, hi: 0x9f},
-	{value: 0x4486, lo: 0xaa, hi: 0xab},
-	{value: 0x458a, lo: 0xac, hi: 0xac},
-	{value: 0x4592, lo: 0xad, hi: 0xad},
-	{value: 0x43de, lo: 0xae, hi: 0xb1},
-	{value: 0x43fc, lo: 0xb2, hi: 0xb4},
-	{value: 0x4414, lo: 0xb5, hi: 0xb6},
-	{value: 0x4420, lo: 0xb8, hi: 0xb8},
-	{value: 0x442c, lo: 0xb9, hi: 0xbb},
-	{value: 0x4444, lo: 0xbc, hi: 0xbc},
-	{value: 0x444a, lo: 0xbe, hi: 0xbe},
+	{value: 0x4402, lo: 0x9f, hi: 0x9f},
+	{value: 0x43f0, lo: 0xaa, hi: 0xab},
+	{value: 0x44f4, lo: 0xac, hi: 0xac},
+	{value: 0x44fc, lo: 0xad, hi: 0xad},
+	{value: 0x4348, lo: 0xae, hi: 0xb1},
+	{value: 0x4366, lo: 0xb2, hi: 0xb4},
+	{value: 0x437e, lo: 0xb5, hi: 0xb6},
+	{value: 0x438a, lo: 0xb8, hi: 0xb8},
+	{value: 0x4396, lo: 0xb9, hi: 0xbb},
+	{value: 0x43ae, lo: 0xbc, hi: 0xbc},
+	{value: 0x43b4, lo: 0xbe, hi: 0xbe},
 	// Block 0x64, offset 0x209
 	{value: 0x0006, lo: 0x08},
-	{value: 0x4450, lo: 0x80, hi: 0x81},
-	{value: 0x445c, lo: 0x83, hi: 0x84},
-	{value: 0x446e, lo: 0x86, hi: 0x89},
-	{value: 0x4492, lo: 0x8a, hi: 0x8a},
-	{value: 0x440e, lo: 0x8b, hi: 0x8b},
-	{value: 0x43f6, lo: 0x8c, hi: 0x8c},
-	{value: 0x443e, lo: 0x8d, hi: 0x8d},
-	{value: 0x4468, lo: 0x8e, hi: 0x8e},
+	{value: 0x43ba, lo: 0x80, hi: 0x81},
+	{value: 0x43c6, lo: 0x83, hi: 0x84},
+	{value: 0x43d8, lo: 0x86, hi: 0x89},
+	{value: 0x43fc, lo: 0x8a, hi: 0x8a},
+	{value: 0x4378, lo: 0x8b, hi: 0x8b},
+	{value: 0x4360, lo: 0x8c, hi: 0x8c},
+	{value: 0x43a8, lo: 0x8d, hi: 0x8d},
+	{value: 0x43d2, lo: 0x8e, hi: 0x8e},
 	// Block 0x65, offset 0x212
 	{value: 0x0000, lo: 0x02},
 	{value: 0x8100, lo: 0xa4, hi: 0xa5},
@@ -4179,16 +4185,16 @@
 	{value: 0x8100, lo: 0xb5, hi: 0xba},
 	// Block 0x6e, offset 0x22c
 	{value: 0x0000, lo: 0x04},
-	{value: 0x4a81, lo: 0x9e, hi: 0x9f},
-	{value: 0x4a81, lo: 0xa3, hi: 0xa3},
-	{value: 0x4a81, lo: 0xa5, hi: 0xa6},
-	{value: 0x4a81, lo: 0xaa, hi: 0xaf},
+	{value: 0x4a9f, lo: 0x9e, hi: 0x9f},
+	{value: 0x4a9f, lo: 0xa3, hi: 0xa3},
+	{value: 0x4a9f, lo: 0xa5, hi: 0xa6},
+	{value: 0x4a9f, lo: 0xaa, hi: 0xaf},
 	// Block 0x6f, offset 0x231
 	{value: 0x0000, lo: 0x05},
-	{value: 0x4a81, lo: 0x82, hi: 0x87},
-	{value: 0x4a81, lo: 0x8a, hi: 0x8f},
-	{value: 0x4a81, lo: 0x92, hi: 0x97},
-	{value: 0x4a81, lo: 0x9a, hi: 0x9c},
+	{value: 0x4a9f, lo: 0x82, hi: 0x87},
+	{value: 0x4a9f, lo: 0x8a, hi: 0x8f},
+	{value: 0x4a9f, lo: 0x92, hi: 0x97},
+	{value: 0x4a9f, lo: 0x9a, hi: 0x9c},
 	{value: 0x8100, lo: 0xa3, hi: 0xa3},
 	// Block 0x70, offset 0x237
 	{value: 0x0000, lo: 0x01},
@@ -4295,13 +4301,13 @@
 	{value: 0x8101, lo: 0x9e, hi: 0x9e},
 	// Block 0x86, offset 0x288
 	{value: 0x0000, lo: 0x0c},
-	{value: 0x4662, lo: 0x9e, hi: 0x9e},
-	{value: 0x466c, lo: 0x9f, hi: 0x9f},
-	{value: 0x46a0, lo: 0xa0, hi: 0xa0},
-	{value: 0x46ae, lo: 0xa1, hi: 0xa1},
-	{value: 0x46bc, lo: 0xa2, hi: 0xa2},
-	{value: 0x46ca, lo: 0xa3, hi: 0xa3},
-	{value: 0x46d8, lo: 0xa4, hi: 0xa4},
+	{value: 0x45cc, lo: 0x9e, hi: 0x9e},
+	{value: 0x45d6, lo: 0x9f, hi: 0x9f},
+	{value: 0x460a, lo: 0xa0, hi: 0xa0},
+	{value: 0x4618, lo: 0xa1, hi: 0xa1},
+	{value: 0x4626, lo: 0xa2, hi: 0xa2},
+	{value: 0x4634, lo: 0xa3, hi: 0xa3},
+	{value: 0x4642, lo: 0xa4, hi: 0xa4},
 	{value: 0x812b, lo: 0xa5, hi: 0xa6},
 	{value: 0x8101, lo: 0xa7, hi: 0xa9},
 	{value: 0x8130, lo: 0xad, hi: 0xad},
@@ -4313,14 +4319,14 @@
 	{value: 0x8132, lo: 0x85, hi: 0x89},
 	{value: 0x812d, lo: 0x8a, hi: 0x8b},
 	{value: 0x8132, lo: 0xaa, hi: 0xad},
-	{value: 0x4676, lo: 0xbb, hi: 0xbb},
-	{value: 0x4680, lo: 0xbc, hi: 0xbc},
-	{value: 0x46e6, lo: 0xbd, hi: 0xbd},
-	{value: 0x4702, lo: 0xbe, hi: 0xbe},
-	{value: 0x46f4, lo: 0xbf, hi: 0xbf},
+	{value: 0x45e0, lo: 0xbb, hi: 0xbb},
+	{value: 0x45ea, lo: 0xbc, hi: 0xbc},
+	{value: 0x4650, lo: 0xbd, hi: 0xbd},
+	{value: 0x466c, lo: 0xbe, hi: 0xbe},
+	{value: 0x465e, lo: 0xbf, hi: 0xbf},
 	// Block 0x88, offset 0x29f
 	{value: 0x0000, lo: 0x01},
-	{value: 0x4710, lo: 0x80, hi: 0x80},
+	{value: 0x467a, lo: 0x80, hi: 0x80},
 	// Block 0x89, offset 0x2a1
 	{value: 0x0000, lo: 0x01},
 	{value: 0x8132, lo: 0x82, hi: 0x84},
@@ -4513,7 +4519,7 @@
 	return 0
 }
 
-// nfkcTrie. Total size: 16994 bytes (16.60 KiB). Checksum: 146925fc21092b17.
+// nfkcTrie. Total size: 16994 bytes (16.60 KiB). Checksum: c3ed54ee046f3c46.
 type nfkcTrie struct{}
 
 func newNfkcTrie(i int) *nfkcTrie {
@@ -4549,22 +4555,22 @@
 	0x76: 0xa000, 0x77: 0xa000, 0x78: 0xa000, 0x79: 0xa000, 0x7a: 0xa000,
 	// Block 0x2, offset 0x80
 	// Block 0x3, offset 0xc0
-	0xc0: 0x2f6f, 0xc1: 0x2f74, 0xc2: 0x471e, 0xc3: 0x2f79, 0xc4: 0x472d, 0xc5: 0x4732,
-	0xc6: 0xa000, 0xc7: 0x473c, 0xc8: 0x2fe2, 0xc9: 0x2fe7, 0xca: 0x4741, 0xcb: 0x2ffb,
-	0xcc: 0x306e, 0xcd: 0x3073, 0xce: 0x3078, 0xcf: 0x4755, 0xd1: 0x3104,
-	0xd2: 0x3127, 0xd3: 0x312c, 0xd4: 0x475f, 0xd5: 0x4764, 0xd6: 0x4773,
-	0xd8: 0xa000, 0xd9: 0x31b3, 0xda: 0x31b8, 0xdb: 0x31bd, 0xdc: 0x47a5, 0xdd: 0x3235,
-	0xe0: 0x327b, 0xe1: 0x3280, 0xe2: 0x47af, 0xe3: 0x3285,
-	0xe4: 0x47be, 0xe5: 0x47c3, 0xe6: 0xa000, 0xe7: 0x47cd, 0xe8: 0x32ee, 0xe9: 0x32f3,
-	0xea: 0x47d2, 0xeb: 0x3307, 0xec: 0x337f, 0xed: 0x3384, 0xee: 0x3389, 0xef: 0x47e6,
-	0xf1: 0x3415, 0xf2: 0x3438, 0xf3: 0x343d, 0xf4: 0x47f0, 0xf5: 0x47f5,
-	0xf6: 0x4804, 0xf8: 0xa000, 0xf9: 0x34c9, 0xfa: 0x34ce, 0xfb: 0x34d3,
-	0xfc: 0x4836, 0xfd: 0x3550, 0xff: 0x3569,
+	0xc0: 0x2f6f, 0xc1: 0x2f74, 0xc2: 0x4688, 0xc3: 0x2f79, 0xc4: 0x4697, 0xc5: 0x469c,
+	0xc6: 0xa000, 0xc7: 0x46a6, 0xc8: 0x2fe2, 0xc9: 0x2fe7, 0xca: 0x46ab, 0xcb: 0x2ffb,
+	0xcc: 0x306e, 0xcd: 0x3073, 0xce: 0x3078, 0xcf: 0x46bf, 0xd1: 0x3104,
+	0xd2: 0x3127, 0xd3: 0x312c, 0xd4: 0x46c9, 0xd5: 0x46ce, 0xd6: 0x46dd,
+	0xd8: 0xa000, 0xd9: 0x31b3, 0xda: 0x31b8, 0xdb: 0x31bd, 0xdc: 0x470f, 0xdd: 0x3235,
+	0xe0: 0x327b, 0xe1: 0x3280, 0xe2: 0x4719, 0xe3: 0x3285,
+	0xe4: 0x4728, 0xe5: 0x472d, 0xe6: 0xa000, 0xe7: 0x4737, 0xe8: 0x32ee, 0xe9: 0x32f3,
+	0xea: 0x473c, 0xeb: 0x3307, 0xec: 0x337f, 0xed: 0x3384, 0xee: 0x3389, 0xef: 0x4750,
+	0xf1: 0x3415, 0xf2: 0x3438, 0xf3: 0x343d, 0xf4: 0x475a, 0xf5: 0x475f,
+	0xf6: 0x476e, 0xf8: 0xa000, 0xf9: 0x34c9, 0xfa: 0x34ce, 0xfb: 0x34d3,
+	0xfc: 0x47a0, 0xfd: 0x3550, 0xff: 0x3569,
 	// Block 0x4, offset 0x100
-	0x100: 0x2f7e, 0x101: 0x328a, 0x102: 0x4723, 0x103: 0x47b4, 0x104: 0x2f9c, 0x105: 0x32a8,
+	0x100: 0x2f7e, 0x101: 0x328a, 0x102: 0x468d, 0x103: 0x471e, 0x104: 0x2f9c, 0x105: 0x32a8,
 	0x106: 0x2fb0, 0x107: 0x32bc, 0x108: 0x2fb5, 0x109: 0x32c1, 0x10a: 0x2fba, 0x10b: 0x32c6,
 	0x10c: 0x2fbf, 0x10d: 0x32cb, 0x10e: 0x2fc9, 0x10f: 0x32d5,
-	0x112: 0x4746, 0x113: 0x47d7, 0x114: 0x2ff1, 0x115: 0x32fd, 0x116: 0x2ff6, 0x117: 0x3302,
+	0x112: 0x46b0, 0x113: 0x4741, 0x114: 0x2ff1, 0x115: 0x32fd, 0x116: 0x2ff6, 0x117: 0x3302,
 	0x118: 0x3014, 0x119: 0x3320, 0x11a: 0x3005, 0x11b: 0x3311, 0x11c: 0x302d, 0x11d: 0x3339,
 	0x11e: 0x3037, 0x11f: 0x3343, 0x120: 0x303c, 0x121: 0x3348, 0x122: 0x3046, 0x123: 0x3352,
 	0x124: 0x304b, 0x125: 0x3357, 0x128: 0x307d, 0x129: 0x338e,
@@ -4575,12 +4581,12 @@
 	// Block 0x5, offset 0x140
 	0x140: 0x1c34, 0x143: 0x30ff, 0x144: 0x3410, 0x145: 0x3118,
 	0x146: 0x3429, 0x147: 0x310e, 0x148: 0x341f, 0x149: 0x1c5c,
-	0x14c: 0x4769, 0x14d: 0x47fa, 0x14e: 0x3131, 0x14f: 0x3442, 0x150: 0x313b, 0x151: 0x344c,
+	0x14c: 0x46d3, 0x14d: 0x4764, 0x14e: 0x3131, 0x14f: 0x3442, 0x150: 0x313b, 0x151: 0x344c,
 	0x154: 0x3159, 0x155: 0x346a, 0x156: 0x3172, 0x157: 0x3483,
-	0x158: 0x3163, 0x159: 0x3474, 0x15a: 0x478c, 0x15b: 0x481d, 0x15c: 0x317c, 0x15d: 0x348d,
-	0x15e: 0x318b, 0x15f: 0x349c, 0x160: 0x4791, 0x161: 0x4822, 0x162: 0x31a4, 0x163: 0x34ba,
-	0x164: 0x3195, 0x165: 0x34ab, 0x168: 0x479b, 0x169: 0x482c,
-	0x16a: 0x47a0, 0x16b: 0x4831, 0x16c: 0x31c2, 0x16d: 0x34d8, 0x16e: 0x31cc, 0x16f: 0x34e2,
+	0x158: 0x3163, 0x159: 0x3474, 0x15a: 0x46f6, 0x15b: 0x4787, 0x15c: 0x317c, 0x15d: 0x348d,
+	0x15e: 0x318b, 0x15f: 0x349c, 0x160: 0x46fb, 0x161: 0x478c, 0x162: 0x31a4, 0x163: 0x34ba,
+	0x164: 0x3195, 0x165: 0x34ab, 0x168: 0x4705, 0x169: 0x4796,
+	0x16a: 0x470a, 0x16b: 0x479b, 0x16c: 0x31c2, 0x16d: 0x34d8, 0x16e: 0x31cc, 0x16f: 0x34e2,
 	0x170: 0x31d1, 0x171: 0x34e7, 0x172: 0x31ef, 0x173: 0x3505, 0x174: 0x3212, 0x175: 0x3528,
 	0x176: 0x323a, 0x177: 0x3555, 0x178: 0x324e, 0x179: 0x325d, 0x17a: 0x357d, 0x17b: 0x3267,
 	0x17c: 0x3587, 0x17d: 0x326c, 0x17e: 0x358c, 0x17f: 0x00a7,
@@ -4592,7 +4598,7 @@
 	0x198: 0x3b57, 0x199: 0x39d6, 0x19a: 0x3b65, 0x19b: 0x39c1, 0x19c: 0x3b50,
 	0x19e: 0x38b0, 0x19f: 0x3a3f, 0x1a0: 0x38a9, 0x1a1: 0x3a38, 0x1a2: 0x35b3, 0x1a3: 0x35c5,
 	0x1a6: 0x3041, 0x1a7: 0x334d, 0x1a8: 0x30be, 0x1a9: 0x33cf,
-	0x1aa: 0x4782, 0x1ab: 0x4813, 0x1ac: 0x3990, 0x1ad: 0x3b1f, 0x1ae: 0x35d7, 0x1af: 0x35dd,
+	0x1aa: 0x46ec, 0x1ab: 0x477d, 0x1ac: 0x3990, 0x1ad: 0x3b1f, 0x1ae: 0x35d7, 0x1af: 0x35dd,
 	0x1b0: 0x33c5, 0x1b1: 0x1942, 0x1b2: 0x1945, 0x1b3: 0x19cf, 0x1b4: 0x3028, 0x1b5: 0x3334,
 	0x1b8: 0x30fa, 0x1b9: 0x340b, 0x1ba: 0x38b7, 0x1bb: 0x3a46,
 	0x1bc: 0x35ad, 0x1bd: 0x35bf, 0x1be: 0x35b9, 0x1bf: 0x35cb,
@@ -4603,8 +4609,8 @@
 	0x1d2: 0x316d, 0x1d3: 0x347e, 0x1d4: 0x31db, 0x1d5: 0x34f1, 0x1d6: 0x31e0, 0x1d7: 0x34f6,
 	0x1d8: 0x3186, 0x1d9: 0x3497, 0x1da: 0x319f, 0x1db: 0x34b5,
 	0x1de: 0x305a, 0x1df: 0x3366,
-	0x1e6: 0x4728, 0x1e7: 0x47b9, 0x1e8: 0x4750, 0x1e9: 0x47e1,
-	0x1ea: 0x395f, 0x1eb: 0x3aee, 0x1ec: 0x393c, 0x1ed: 0x3acb, 0x1ee: 0x476e, 0x1ef: 0x47ff,
+	0x1e6: 0x4692, 0x1e7: 0x4723, 0x1e8: 0x46ba, 0x1e9: 0x474b,
+	0x1ea: 0x395f, 0x1eb: 0x3aee, 0x1ec: 0x393c, 0x1ed: 0x3acb, 0x1ee: 0x46d8, 0x1ef: 0x4769,
 	0x1f0: 0x3958, 0x1f1: 0x3ae7, 0x1f2: 0x3244, 0x1f3: 0x355f,
 	// Block 0x8, offset 0x200
 	0x200: 0x9932, 0x201: 0x9932, 0x202: 0x9932, 0x203: 0x9932, 0x204: 0x9932, 0x205: 0x8132,
@@ -4619,7 +4625,7 @@
 	0x236: 0x8101, 0x237: 0x8101, 0x238: 0x9901, 0x239: 0x812d, 0x23a: 0x812d, 0x23b: 0x812d,
 	0x23c: 0x812d, 0x23d: 0x8132, 0x23e: 0x8132, 0x23f: 0x8132,
 	// Block 0x9, offset 0x240
-	0x240: 0x4a44, 0x241: 0x4a49, 0x242: 0x9932, 0x243: 0x4a4e, 0x244: 0x4a53, 0x245: 0x9936,
+	0x240: 0x49ae, 0x241: 0x49b3, 0x242: 0x9932, 0x243: 0x49b8, 0x244: 0x4a71, 0x245: 0x9936,
 	0x246: 0x8132, 0x247: 0x812d, 0x248: 0x812d, 0x249: 0x812d, 0x24a: 0x8132, 0x24b: 0x8132,
 	0x24c: 0x8132, 0x24d: 0x812d, 0x24e: 0x812d, 0x250: 0x8132, 0x251: 0x8132,
 	0x252: 0x8132, 0x253: 0x812d, 0x254: 0x812d, 0x255: 0x812d, 0x256: 0x812d, 0x257: 0x8132,
@@ -4631,22 +4637,22 @@
 	0x27a: 0x42a5,
 	0x27e: 0x0037,
 	// Block 0xa, offset 0x280
-	0x284: 0x425a, 0x285: 0x4511,
+	0x284: 0x425a, 0x285: 0x447b,
 	0x286: 0x35e9, 0x287: 0x00ce, 0x288: 0x3607, 0x289: 0x3613, 0x28a: 0x3625,
 	0x28c: 0x3643, 0x28e: 0x3655, 0x28f: 0x3673, 0x290: 0x3e08, 0x291: 0xa000,
 	0x295: 0xa000, 0x297: 0xa000,
 	0x299: 0xa000,
 	0x29f: 0xa000, 0x2a1: 0xa000,
 	0x2a5: 0xa000, 0x2a9: 0xa000,
-	0x2aa: 0x3637, 0x2ab: 0x3667, 0x2ac: 0x4894, 0x2ad: 0x3697, 0x2ae: 0x48be, 0x2af: 0x36a9,
+	0x2aa: 0x3637, 0x2ab: 0x3667, 0x2ac: 0x47fe, 0x2ad: 0x3697, 0x2ae: 0x4828, 0x2af: 0x36a9,
 	0x2b0: 0x3e70, 0x2b1: 0xa000, 0x2b5: 0xa000,
 	0x2b7: 0xa000, 0x2b9: 0xa000,
 	0x2bf: 0xa000,
 	// Block 0xb, offset 0x2c0
 	0x2c1: 0xa000, 0x2c5: 0xa000,
-	0x2c9: 0xa000, 0x2ca: 0x48d6, 0x2cb: 0x48f4,
-	0x2cc: 0x36c7, 0x2cd: 0x36df, 0x2ce: 0x490c, 0x2d0: 0x01be, 0x2d1: 0x01d0,
-	0x2d2: 0x01ac, 0x2d3: 0x43a2, 0x2d4: 0x43a8, 0x2d5: 0x01fa, 0x2d6: 0x01e8,
+	0x2c9: 0xa000, 0x2ca: 0x4840, 0x2cb: 0x485e,
+	0x2cc: 0x36c7, 0x2cd: 0x36df, 0x2ce: 0x4876, 0x2d0: 0x01be, 0x2d1: 0x01d0,
+	0x2d2: 0x01ac, 0x2d3: 0x430c, 0x2d4: 0x4312, 0x2d5: 0x01fa, 0x2d6: 0x01e8,
 	0x2f0: 0x01d6, 0x2f1: 0x01eb, 0x2f2: 0x01ee, 0x2f4: 0x0188, 0x2f5: 0x01c7,
 	0x2f9: 0x01a6,
 	// Block 0xc, offset 0x300
@@ -4726,15 +4732,15 @@
 	0x4e4: 0x305f, 0x4e5: 0x336b, 0x4e6: 0x3055, 0x4e7: 0x3361, 0x4e8: 0x3064, 0x4e9: 0x3370,
 	0x4ea: 0x3069, 0x4eb: 0x3375, 0x4ec: 0x30af, 0x4ed: 0x33bb, 0x4ee: 0x390b, 0x4ef: 0x3a9a,
 	0x4f0: 0x30b9, 0x4f1: 0x33ca, 0x4f2: 0x30c3, 0x4f3: 0x33d4, 0x4f4: 0x30cd, 0x4f5: 0x33de,
-	0x4f6: 0x475a, 0x4f7: 0x47eb, 0x4f8: 0x3912, 0x4f9: 0x3aa1, 0x4fa: 0x30e6, 0x4fb: 0x33f7,
+	0x4f6: 0x46c4, 0x4f7: 0x4755, 0x4f8: 0x3912, 0x4f9: 0x3aa1, 0x4fa: 0x30e6, 0x4fb: 0x33f7,
 	0x4fc: 0x30e1, 0x4fd: 0x33f2, 0x4fe: 0x30eb, 0x4ff: 0x33fc,
 	// Block 0x14, offset 0x500
 	0x500: 0x30f0, 0x501: 0x3401, 0x502: 0x30f5, 0x503: 0x3406, 0x504: 0x3109, 0x505: 0x341a,
 	0x506: 0x3113, 0x507: 0x3424, 0x508: 0x3122, 0x509: 0x3433, 0x50a: 0x311d, 0x50b: 0x342e,
 	0x50c: 0x3935, 0x50d: 0x3ac4, 0x50e: 0x3943, 0x50f: 0x3ad2, 0x510: 0x394a, 0x511: 0x3ad9,
 	0x512: 0x3951, 0x513: 0x3ae0, 0x514: 0x314f, 0x515: 0x3460, 0x516: 0x3154, 0x517: 0x3465,
-	0x518: 0x315e, 0x519: 0x346f, 0x51a: 0x4787, 0x51b: 0x4818, 0x51c: 0x3997, 0x51d: 0x3b26,
-	0x51e: 0x3177, 0x51f: 0x3488, 0x520: 0x3181, 0x521: 0x3492, 0x522: 0x4796, 0x523: 0x4827,
+	0x518: 0x315e, 0x519: 0x346f, 0x51a: 0x46f1, 0x51b: 0x4782, 0x51c: 0x3997, 0x51d: 0x3b26,
+	0x51e: 0x3177, 0x51f: 0x3488, 0x520: 0x3181, 0x521: 0x3492, 0x522: 0x4700, 0x523: 0x4791,
 	0x524: 0x399e, 0x525: 0x3b2d, 0x526: 0x39a5, 0x527: 0x3b34, 0x528: 0x39ac, 0x529: 0x3b3b,
 	0x52a: 0x3190, 0x52b: 0x34a1, 0x52c: 0x319a, 0x52d: 0x34b0, 0x52e: 0x31ae, 0x52f: 0x34c4,
 	0x530: 0x31a9, 0x531: 0x34bf, 0x532: 0x31ea, 0x533: 0x3500, 0x534: 0x31f9, 0x535: 0x350f,
@@ -4746,16 +4752,16 @@
 	0x54c: 0x322b, 0x54d: 0x3546, 0x54e: 0x3249, 0x54f: 0x3564, 0x550: 0x3262, 0x551: 0x3582,
 	0x552: 0x3271, 0x553: 0x3591, 0x554: 0x3276, 0x555: 0x3596, 0x556: 0x337a, 0x557: 0x34a6,
 	0x558: 0x3537, 0x559: 0x3573, 0x55a: 0x1be0, 0x55b: 0x42d7,
-	0x560: 0x4737, 0x561: 0x47c8, 0x562: 0x2f83, 0x563: 0x328f,
+	0x560: 0x46a1, 0x561: 0x4732, 0x562: 0x2f83, 0x563: 0x328f,
 	0x564: 0x3878, 0x565: 0x3a07, 0x566: 0x3871, 0x567: 0x3a00, 0x568: 0x3886, 0x569: 0x3a15,
 	0x56a: 0x387f, 0x56b: 0x3a0e, 0x56c: 0x38be, 0x56d: 0x3a4d, 0x56e: 0x3894, 0x56f: 0x3a23,
 	0x570: 0x388d, 0x571: 0x3a1c, 0x572: 0x38a2, 0x573: 0x3a31, 0x574: 0x389b, 0x575: 0x3a2a,
-	0x576: 0x38c5, 0x577: 0x3a54, 0x578: 0x474b, 0x579: 0x47dc, 0x57a: 0x3000, 0x57b: 0x330c,
+	0x576: 0x38c5, 0x577: 0x3a54, 0x578: 0x46b5, 0x579: 0x4746, 0x57a: 0x3000, 0x57b: 0x330c,
 	0x57c: 0x2fec, 0x57d: 0x32f8, 0x57e: 0x38da, 0x57f: 0x3a69,
 	// Block 0x16, offset 0x580
 	0x580: 0x38d3, 0x581: 0x3a62, 0x582: 0x38e8, 0x583: 0x3a77, 0x584: 0x38e1, 0x585: 0x3a70,
 	0x586: 0x38fd, 0x587: 0x3a8c, 0x588: 0x3091, 0x589: 0x339d, 0x58a: 0x30a5, 0x58b: 0x33b1,
-	0x58c: 0x477d, 0x58d: 0x480e, 0x58e: 0x3136, 0x58f: 0x3447, 0x590: 0x3920, 0x591: 0x3aaf,
+	0x58c: 0x46e7, 0x58d: 0x4778, 0x58e: 0x3136, 0x58f: 0x3447, 0x590: 0x3920, 0x591: 0x3aaf,
 	0x592: 0x3919, 0x593: 0x3aa8, 0x594: 0x392e, 0x595: 0x3abd, 0x596: 0x3927, 0x597: 0x3ab6,
 	0x598: 0x3989, 0x599: 0x3b18, 0x59a: 0x396d, 0x59b: 0x3afc, 0x59c: 0x3966, 0x59d: 0x3af5,
 	0x59e: 0x397b, 0x59f: 0x3b0a, 0x5a0: 0x3974, 0x5a1: 0x3b03, 0x5a2: 0x3982, 0x5a3: 0x3b11,
@@ -4764,29 +4770,29 @@
 	0x5b0: 0x39f9, 0x5b1: 0x3b88, 0x5b2: 0x3230, 0x5b3: 0x354b, 0x5b4: 0x3258, 0x5b5: 0x3578,
 	0x5b6: 0x3253, 0x5b7: 0x356e, 0x5b8: 0x323f, 0x5b9: 0x355a,
 	// Block 0x17, offset 0x5c0
-	0x5c0: 0x489a, 0x5c1: 0x48a0, 0x5c2: 0x49b4, 0x5c3: 0x49cc, 0x5c4: 0x49bc, 0x5c5: 0x49d4,
-	0x5c6: 0x49c4, 0x5c7: 0x49dc, 0x5c8: 0x4840, 0x5c9: 0x4846, 0x5ca: 0x4924, 0x5cb: 0x493c,
-	0x5cc: 0x492c, 0x5cd: 0x4944, 0x5ce: 0x4934, 0x5cf: 0x494c, 0x5d0: 0x48ac, 0x5d1: 0x48b2,
+	0x5c0: 0x4804, 0x5c1: 0x480a, 0x5c2: 0x491e, 0x5c3: 0x4936, 0x5c4: 0x4926, 0x5c5: 0x493e,
+	0x5c6: 0x492e, 0x5c7: 0x4946, 0x5c8: 0x47aa, 0x5c9: 0x47b0, 0x5ca: 0x488e, 0x5cb: 0x48a6,
+	0x5cc: 0x4896, 0x5cd: 0x48ae, 0x5ce: 0x489e, 0x5cf: 0x48b6, 0x5d0: 0x4816, 0x5d1: 0x481c,
 	0x5d2: 0x3db8, 0x5d3: 0x3dc8, 0x5d4: 0x3dc0, 0x5d5: 0x3dd0,
-	0x5d8: 0x484c, 0x5d9: 0x4852, 0x5da: 0x3ce8, 0x5db: 0x3cf8, 0x5dc: 0x3cf0, 0x5dd: 0x3d00,
-	0x5e0: 0x48c4, 0x5e1: 0x48ca, 0x5e2: 0x49e4, 0x5e3: 0x49fc,
-	0x5e4: 0x49ec, 0x5e5: 0x4a04, 0x5e6: 0x49f4, 0x5e7: 0x4a0c, 0x5e8: 0x4858, 0x5e9: 0x485e,
-	0x5ea: 0x4954, 0x5eb: 0x496c, 0x5ec: 0x495c, 0x5ed: 0x4974, 0x5ee: 0x4964, 0x5ef: 0x497c,
-	0x5f0: 0x48dc, 0x5f1: 0x48e2, 0x5f2: 0x3e18, 0x5f3: 0x3e30, 0x5f4: 0x3e20, 0x5f5: 0x3e38,
-	0x5f6: 0x3e28, 0x5f7: 0x3e40, 0x5f8: 0x4864, 0x5f9: 0x486a, 0x5fa: 0x3d18, 0x5fb: 0x3d30,
+	0x5d8: 0x47b6, 0x5d9: 0x47bc, 0x5da: 0x3ce8, 0x5db: 0x3cf8, 0x5dc: 0x3cf0, 0x5dd: 0x3d00,
+	0x5e0: 0x482e, 0x5e1: 0x4834, 0x5e2: 0x494e, 0x5e3: 0x4966,
+	0x5e4: 0x4956, 0x5e5: 0x496e, 0x5e6: 0x495e, 0x5e7: 0x4976, 0x5e8: 0x47c2, 0x5e9: 0x47c8,
+	0x5ea: 0x48be, 0x5eb: 0x48d6, 0x5ec: 0x48c6, 0x5ed: 0x48de, 0x5ee: 0x48ce, 0x5ef: 0x48e6,
+	0x5f0: 0x4846, 0x5f1: 0x484c, 0x5f2: 0x3e18, 0x5f3: 0x3e30, 0x5f4: 0x3e20, 0x5f5: 0x3e38,
+	0x5f6: 0x3e28, 0x5f7: 0x3e40, 0x5f8: 0x47ce, 0x5f9: 0x47d4, 0x5fa: 0x3d18, 0x5fb: 0x3d30,
 	0x5fc: 0x3d20, 0x5fd: 0x3d38, 0x5fe: 0x3d28, 0x5ff: 0x3d40,
 	// Block 0x18, offset 0x600
-	0x600: 0x48e8, 0x601: 0x48ee, 0x602: 0x3e48, 0x603: 0x3e58, 0x604: 0x3e50, 0x605: 0x3e60,
-	0x608: 0x4870, 0x609: 0x4876, 0x60a: 0x3d48, 0x60b: 0x3d58,
-	0x60c: 0x3d50, 0x60d: 0x3d60, 0x610: 0x48fa, 0x611: 0x4900,
+	0x600: 0x4852, 0x601: 0x4858, 0x602: 0x3e48, 0x603: 0x3e58, 0x604: 0x3e50, 0x605: 0x3e60,
+	0x608: 0x47da, 0x609: 0x47e0, 0x60a: 0x3d48, 0x60b: 0x3d58,
+	0x60c: 0x3d50, 0x60d: 0x3d60, 0x610: 0x4864, 0x611: 0x486a,
 	0x612: 0x3e80, 0x613: 0x3e98, 0x614: 0x3e88, 0x615: 0x3ea0, 0x616: 0x3e90, 0x617: 0x3ea8,
-	0x619: 0x487c, 0x61b: 0x3d68, 0x61d: 0x3d70,
-	0x61f: 0x3d78, 0x620: 0x4912, 0x621: 0x4918, 0x622: 0x4a14, 0x623: 0x4a2c,
-	0x624: 0x4a1c, 0x625: 0x4a34, 0x626: 0x4a24, 0x627: 0x4a3c, 0x628: 0x4882, 0x629: 0x4888,
-	0x62a: 0x4984, 0x62b: 0x499c, 0x62c: 0x498c, 0x62d: 0x49a4, 0x62e: 0x4994, 0x62f: 0x49ac,
-	0x630: 0x488e, 0x631: 0x43b4, 0x632: 0x3691, 0x633: 0x43ba, 0x634: 0x48b8, 0x635: 0x43c0,
-	0x636: 0x36a3, 0x637: 0x43c6, 0x638: 0x36c1, 0x639: 0x43cc, 0x63a: 0x36d9, 0x63b: 0x43d2,
-	0x63c: 0x4906, 0x63d: 0x43d8,
+	0x619: 0x47e6, 0x61b: 0x3d68, 0x61d: 0x3d70,
+	0x61f: 0x3d78, 0x620: 0x487c, 0x621: 0x4882, 0x622: 0x497e, 0x623: 0x4996,
+	0x624: 0x4986, 0x625: 0x499e, 0x626: 0x498e, 0x627: 0x49a6, 0x628: 0x47ec, 0x629: 0x47f2,
+	0x62a: 0x48ee, 0x62b: 0x4906, 0x62c: 0x48f6, 0x62d: 0x490e, 0x62e: 0x48fe, 0x62f: 0x4916,
+	0x630: 0x47f8, 0x631: 0x431e, 0x632: 0x3691, 0x633: 0x4324, 0x634: 0x4822, 0x635: 0x432a,
+	0x636: 0x36a3, 0x637: 0x4330, 0x638: 0x36c1, 0x639: 0x4336, 0x63a: 0x36d9, 0x63b: 0x433c,
+	0x63c: 0x4870, 0x63d: 0x4342,
 	// Block 0x19, offset 0x640
 	0x640: 0x3da0, 0x641: 0x3da8, 0x642: 0x4184, 0x643: 0x41a2, 0x644: 0x418e, 0x645: 0x41ac,
 	0x646: 0x4198, 0x647: 0x41b6, 0x648: 0x3cd8, 0x649: 0x3ce0, 0x64a: 0x40d0, 0x64b: 0x40ee,
@@ -4797,19 +4803,19 @@
 	0x664: 0x4206, 0x665: 0x4224, 0x666: 0x4210, 0x667: 0x422e, 0x668: 0x3d80, 0x669: 0x3d88,
 	0x66a: 0x4148, 0x66b: 0x4166, 0x66c: 0x4152, 0x66d: 0x4170, 0x66e: 0x415c, 0x66f: 0x417a,
 	0x670: 0x3685, 0x671: 0x367f, 0x672: 0x3d90, 0x673: 0x368b, 0x674: 0x3d98,
-	0x676: 0x48a6, 0x677: 0x3db0, 0x678: 0x35f5, 0x679: 0x35ef, 0x67a: 0x35e3, 0x67b: 0x4384,
+	0x676: 0x4810, 0x677: 0x3db0, 0x678: 0x35f5, 0x679: 0x35ef, 0x67a: 0x35e3, 0x67b: 0x42ee,
 	0x67c: 0x35fb, 0x67d: 0x4287, 0x67e: 0x01d3, 0x67f: 0x4287,
 	// Block 0x1a, offset 0x680
-	0x680: 0x42a0, 0x681: 0x4518, 0x682: 0x3dd8, 0x683: 0x369d, 0x684: 0x3de0,
-	0x686: 0x48d0, 0x687: 0x3df8, 0x688: 0x3601, 0x689: 0x438a, 0x68a: 0x360d, 0x68b: 0x4390,
-	0x68c: 0x3619, 0x68d: 0x451f, 0x68e: 0x4526, 0x68f: 0x452d, 0x690: 0x36b5, 0x691: 0x36af,
-	0x692: 0x3e00, 0x693: 0x457a, 0x696: 0x36bb, 0x697: 0x3e10,
-	0x698: 0x3631, 0x699: 0x362b, 0x69a: 0x361f, 0x69b: 0x4396, 0x69d: 0x4534,
-	0x69e: 0x453b, 0x69f: 0x4542, 0x6a0: 0x36eb, 0x6a1: 0x36e5, 0x6a2: 0x3e68, 0x6a3: 0x4582,
+	0x680: 0x42a0, 0x681: 0x4482, 0x682: 0x3dd8, 0x683: 0x369d, 0x684: 0x3de0,
+	0x686: 0x483a, 0x687: 0x3df8, 0x688: 0x3601, 0x689: 0x42f4, 0x68a: 0x360d, 0x68b: 0x42fa,
+	0x68c: 0x3619, 0x68d: 0x4489, 0x68e: 0x4490, 0x68f: 0x4497, 0x690: 0x36b5, 0x691: 0x36af,
+	0x692: 0x3e00, 0x693: 0x44e4, 0x696: 0x36bb, 0x697: 0x3e10,
+	0x698: 0x3631, 0x699: 0x362b, 0x69a: 0x361f, 0x69b: 0x4300, 0x69d: 0x449e,
+	0x69e: 0x44a5, 0x69f: 0x44ac, 0x6a0: 0x36eb, 0x6a1: 0x36e5, 0x6a2: 0x3e68, 0x6a3: 0x44ec,
 	0x6a4: 0x36cd, 0x6a5: 0x36d3, 0x6a6: 0x36f1, 0x6a7: 0x3e78, 0x6a8: 0x3661, 0x6a9: 0x365b,
-	0x6aa: 0x364f, 0x6ab: 0x43a2, 0x6ac: 0x3649, 0x6ad: 0x450a, 0x6ae: 0x4511, 0x6af: 0x0081,
+	0x6aa: 0x364f, 0x6ab: 0x430c, 0x6ac: 0x3649, 0x6ad: 0x4474, 0x6ae: 0x447b, 0x6af: 0x0081,
 	0x6b2: 0x3eb0, 0x6b3: 0x36f7, 0x6b4: 0x3eb8,
-	0x6b6: 0x491e, 0x6b7: 0x3ed0, 0x6b8: 0x363d, 0x6b9: 0x439c, 0x6ba: 0x366d, 0x6bb: 0x43ae,
+	0x6b6: 0x4888, 0x6b7: 0x3ed0, 0x6b8: 0x363d, 0x6b9: 0x4306, 0x6ba: 0x366d, 0x6bb: 0x4318,
 	0x6bc: 0x3679, 0x6bd: 0x425a, 0x6be: 0x428c,
 	// Block 0x1b, offset 0x6c0
 	0x6c0: 0x1bd8, 0x6c1: 0x1bdc, 0x6c2: 0x0047, 0x6c3: 0x1c54, 0x6c5: 0x1be8,
@@ -4922,7 +4928,7 @@
 	0x93c: 0x3fc0, 0x93d: 0x3fc8,
 	// Block 0x25, offset 0x940
 	0x954: 0x3f00,
-	0x959: 0x9903, 0x95a: 0x9903, 0x95b: 0x4372, 0x95c: 0x4378, 0x95d: 0xa000,
+	0x959: 0x9903, 0x95a: 0x9903, 0x95b: 0x42dc, 0x95c: 0x42e2, 0x95d: 0xa000,
 	0x95e: 0x3fd0, 0x95f: 0x26b4,
 	0x966: 0xa000,
 	0x96b: 0xa000, 0x96c: 0x3fe0, 0x96d: 0xa000, 0x96e: 0x3fe8, 0x96f: 0xa000,
@@ -4942,10 +4948,10 @@
 	// Block 0x27, offset 0x9c0
 	0x9c0: 0x0367, 0x9c1: 0x032b, 0x9c2: 0x032f, 0x9c3: 0x0333, 0x9c4: 0x037b, 0x9c5: 0x0337,
 	0x9c6: 0x033b, 0x9c7: 0x033f, 0x9c8: 0x0343, 0x9c9: 0x0347, 0x9ca: 0x034b, 0x9cb: 0x034f,
-	0x9cc: 0x0353, 0x9cd: 0x0357, 0x9ce: 0x035b, 0x9cf: 0x42dc, 0x9d0: 0x42e1, 0x9d1: 0x42e6,
-	0x9d2: 0x42eb, 0x9d3: 0x42f0, 0x9d4: 0x42f5, 0x9d5: 0x42fa, 0x9d6: 0x42ff, 0x9d7: 0x4304,
-	0x9d8: 0x4309, 0x9d9: 0x430e, 0x9da: 0x4313, 0x9db: 0x4318, 0x9dc: 0x431d, 0x9dd: 0x4322,
-	0x9de: 0x4327, 0x9df: 0x432c, 0x9e0: 0x4331, 0x9e1: 0x4336, 0x9e2: 0x433b, 0x9e3: 0x4340,
+	0x9cc: 0x0353, 0x9cd: 0x0357, 0x9ce: 0x035b, 0x9cf: 0x49bd, 0x9d0: 0x49c3, 0x9d1: 0x49c9,
+	0x9d2: 0x49cf, 0x9d3: 0x49d5, 0x9d4: 0x49db, 0x9d5: 0x49e1, 0x9d6: 0x49e7, 0x9d7: 0x49ed,
+	0x9d8: 0x49f3, 0x9d9: 0x49f9, 0x9da: 0x49ff, 0x9db: 0x4a05, 0x9dc: 0x4a0b, 0x9dd: 0x4a11,
+	0x9de: 0x4a17, 0x9df: 0x4a1d, 0x9e0: 0x4a23, 0x9e1: 0x4a29, 0x9e2: 0x4a2f, 0x9e3: 0x4a35,
 	0x9e4: 0x03c3, 0x9e5: 0x035f, 0x9e6: 0x0363, 0x9e7: 0x03e7, 0x9e8: 0x03eb, 0x9e9: 0x03ef,
 	0x9ea: 0x03f3, 0x9eb: 0x03f7, 0x9ec: 0x03fb, 0x9ed: 0x03ff, 0x9ee: 0x036b, 0x9ef: 0x0403,
 	0x9f0: 0x0407, 0x9f1: 0x036f, 0x9f2: 0x0373, 0x9f3: 0x0377, 0x9f4: 0x037f, 0x9f5: 0x0383,
@@ -5148,17 +5154,17 @@
 	0xe40: 0x19d5, 0xe41: 0x19d8, 0xe42: 0x19db, 0xe43: 0x1c08, 0xe44: 0x1c0c, 0xe45: 0x1a5f,
 	0xe46: 0x1a5f,
 	0xe53: 0x1d75, 0xe54: 0x1d66, 0xe55: 0x1d6b, 0xe56: 0x1d7a, 0xe57: 0x1d70,
-	0xe5d: 0x4426,
-	0xe5e: 0x8115, 0xe5f: 0x4498, 0xe60: 0x022d, 0xe61: 0x0215, 0xe62: 0x021e, 0xe63: 0x0221,
+	0xe5d: 0x4390,
+	0xe5e: 0x8115, 0xe5f: 0x4402, 0xe60: 0x022d, 0xe61: 0x0215, 0xe62: 0x021e, 0xe63: 0x0221,
 	0xe64: 0x0224, 0xe65: 0x0227, 0xe66: 0x022a, 0xe67: 0x0230, 0xe68: 0x0233, 0xe69: 0x0017,
-	0xe6a: 0x4486, 0xe6b: 0x448c, 0xe6c: 0x458a, 0xe6d: 0x4592, 0xe6e: 0x43de, 0xe6f: 0x43e4,
-	0xe70: 0x43ea, 0xe71: 0x43f0, 0xe72: 0x43fc, 0xe73: 0x4402, 0xe74: 0x4408, 0xe75: 0x4414,
-	0xe76: 0x441a, 0xe78: 0x4420, 0xe79: 0x442c, 0xe7a: 0x4432, 0xe7b: 0x4438,
-	0xe7c: 0x4444, 0xe7e: 0x444a,
+	0xe6a: 0x43f0, 0xe6b: 0x43f6, 0xe6c: 0x44f4, 0xe6d: 0x44fc, 0xe6e: 0x4348, 0xe6f: 0x434e,
+	0xe70: 0x4354, 0xe71: 0x435a, 0xe72: 0x4366, 0xe73: 0x436c, 0xe74: 0x4372, 0xe75: 0x437e,
+	0xe76: 0x4384, 0xe78: 0x438a, 0xe79: 0x4396, 0xe7a: 0x439c, 0xe7b: 0x43a2,
+	0xe7c: 0x43ae, 0xe7e: 0x43b4,
 	// Block 0x3a, offset 0xe80
-	0xe80: 0x4450, 0xe81: 0x4456, 0xe83: 0x445c, 0xe84: 0x4462,
-	0xe86: 0x446e, 0xe87: 0x4474, 0xe88: 0x447a, 0xe89: 0x4480, 0xe8a: 0x4492, 0xe8b: 0x440e,
-	0xe8c: 0x43f6, 0xe8d: 0x443e, 0xe8e: 0x4468, 0xe8f: 0x1d7f, 0xe90: 0x0299, 0xe91: 0x0299,
+	0xe80: 0x43ba, 0xe81: 0x43c0, 0xe83: 0x43c6, 0xe84: 0x43cc,
+	0xe86: 0x43d8, 0xe87: 0x43de, 0xe88: 0x43e4, 0xe89: 0x43ea, 0xe8a: 0x43fc, 0xe8b: 0x4378,
+	0xe8c: 0x4360, 0xe8d: 0x43a8, 0xe8e: 0x43d2, 0xe8f: 0x1d7f, 0xe90: 0x0299, 0xe91: 0x0299,
 	0xe92: 0x02a2, 0xe93: 0x02a2, 0xe94: 0x02a2, 0xe95: 0x02a2, 0xe96: 0x02a5, 0xe97: 0x02a5,
 	0xe98: 0x02a5, 0xe99: 0x02a5, 0xe9a: 0x02ab, 0xe9b: 0x02ab, 0xe9c: 0x02ab, 0xe9d: 0x02ab,
 	0xe9e: 0x029f, 0xe9f: 0x029f, 0xea0: 0x029f, 0xea1: 0x029f, 0xea2: 0x02a8, 0xea3: 0x02a8,
@@ -5174,9 +5180,9 @@
 	0xed2: 0x02db, 0xed3: 0x02db, 0xed4: 0x02db, 0xed5: 0x02db, 0xed6: 0x02e1, 0xed7: 0x02e1,
 	0xed8: 0x02e1, 0xed9: 0x02e1, 0xeda: 0x02de, 0xedb: 0x02de, 0xedc: 0x02de, 0xedd: 0x02de,
 	0xede: 0x02e4, 0xedf: 0x02e4, 0xee0: 0x02e7, 0xee1: 0x02e7, 0xee2: 0x02e7, 0xee3: 0x02e7,
-	0xee4: 0x4504, 0xee5: 0x4504, 0xee6: 0x02ed, 0xee7: 0x02ed, 0xee8: 0x02ed, 0xee9: 0x02ed,
+	0xee4: 0x446e, 0xee5: 0x446e, 0xee6: 0x02ed, 0xee7: 0x02ed, 0xee8: 0x02ed, 0xee9: 0x02ed,
 	0xeea: 0x02ea, 0xeeb: 0x02ea, 0xeec: 0x02ea, 0xeed: 0x02ea, 0xeee: 0x0308, 0xeef: 0x0308,
-	0xef0: 0x44fe, 0xef1: 0x44fe,
+	0xef0: 0x4468, 0xef1: 0x4468,
 	// Block 0x3c, offset 0xf00
 	0xf13: 0x02d8, 0xf14: 0x02d8, 0xf15: 0x02d8, 0xf16: 0x02d8, 0xf17: 0x02f6,
 	0xf18: 0x02f6, 0xf19: 0x02f3, 0xf1a: 0x02f3, 0xf1b: 0x02f9, 0xf1c: 0x02f9, 0xf1d: 0x204f,
@@ -5203,8 +5209,8 @@
 	0xf86: 0x1fb4, 0xf87: 0x1fb9, 0xf88: 0x1fbe, 0xf89: 0x1fc3, 0xf8a: 0x1fc8, 0xf8b: 0x1fcd,
 	0xf8c: 0x1fd2, 0xf8d: 0x1fd7, 0xf8e: 0x1fe6, 0xf8f: 0x1ff5, 0xf90: 0x1ffa, 0xf91: 0x1fff,
 	0xf92: 0x2004, 0xf93: 0x2009, 0xf94: 0x200e, 0xf95: 0x2018, 0xf96: 0x201d, 0xf97: 0x2022,
-	0xf98: 0x2031, 0xf99: 0x2040, 0xf9a: 0x2045, 0xf9b: 0x44b6, 0xf9c: 0x44bc, 0xf9d: 0x44f2,
-	0xf9e: 0x4549, 0xf9f: 0x4550, 0xfa0: 0x4557, 0xfa1: 0x455e, 0xfa2: 0x4565, 0xfa3: 0x456c,
+	0xf98: 0x2031, 0xf99: 0x2040, 0xf9a: 0x2045, 0xf9b: 0x4420, 0xf9c: 0x4426, 0xf9d: 0x445c,
+	0xf9e: 0x44b3, 0xf9f: 0x44ba, 0xfa0: 0x44c1, 0xfa1: 0x44c8, 0xfa2: 0x44cf, 0xfa3: 0x44d6,
 	0xfa4: 0x25c6, 0xfa5: 0x25cd, 0xfa6: 0x25d4, 0xfa7: 0x25db, 0xfa8: 0x25f0, 0xfa9: 0x25f7,
 	0xfaa: 0x1d98, 0xfab: 0x1d9d, 0xfac: 0x1da2, 0xfad: 0x1da7, 0xfae: 0x1db1, 0xfaf: 0x1db6,
 	0xfb0: 0x1dca, 0xfb1: 0x1dcf, 0xfb2: 0x1dd4, 0xfb3: 0x1dd9, 0xfb4: 0x1de3, 0xfb5: 0x1de8,
@@ -5213,7 +5219,7 @@
 	// Block 0x3f, offset 0xfc0
 	0xfc0: 0x1f5a, 0xfc1: 0x1f6e, 0xfc2: 0x1f73, 0xfc3: 0x1f78, 0xfc4: 0x1f7d, 0xfc5: 0x1f96,
 	0xfc6: 0x1fa0, 0xfc7: 0x1fa5, 0xfc8: 0x1faa, 0xfc9: 0x1fbe, 0xfca: 0x1fdc, 0xfcb: 0x1fe1,
-	0xfcc: 0x1fe6, 0xfcd: 0x1feb, 0xfce: 0x1ff5, 0xfcf: 0x1ffa, 0xfd0: 0x44f2, 0xfd1: 0x2027,
+	0xfcc: 0x1fe6, 0xfcd: 0x1feb, 0xfce: 0x1ff5, 0xfcf: 0x1ffa, 0xfd0: 0x445c, 0xfd1: 0x2027,
 	0xfd2: 0x202c, 0xfd3: 0x2031, 0xfd4: 0x2036, 0xfd5: 0x2040, 0xfd6: 0x2045, 0xfd7: 0x25b1,
 	0xfd8: 0x25b8, 0xfd9: 0x25bf, 0xfda: 0x25d4, 0xfdb: 0x25e2, 0xfdc: 0x1d89, 0xfdd: 0x1d8e,
 	0xfde: 0x1d93, 0xfdf: 0x1da2, 0xfe0: 0x1dac, 0xfe1: 0x1dbb, 0xfe2: 0x1dc0, 0xfe3: 0x1dc5,
@@ -5227,11 +5233,11 @@
 	0x1006: 0x1f69, 0x1007: 0x1f6e, 0x1008: 0x1f73, 0x1009: 0x1f87, 0x100a: 0x1f8c, 0x100b: 0x1f91,
 	0x100c: 0x1f96, 0x100d: 0x1f9b, 0x100e: 0x1faf, 0x100f: 0x1fb4, 0x1010: 0x1fb9, 0x1011: 0x1fbe,
 	0x1012: 0x1fcd, 0x1013: 0x1fd2, 0x1014: 0x1fd7, 0x1015: 0x1fe6, 0x1016: 0x1ff0, 0x1017: 0x1fff,
-	0x1018: 0x2004, 0x1019: 0x44e6, 0x101a: 0x2018, 0x101b: 0x201d, 0x101c: 0x2022, 0x101d: 0x2031,
+	0x1018: 0x2004, 0x1019: 0x4450, 0x101a: 0x2018, 0x101b: 0x201d, 0x101c: 0x2022, 0x101d: 0x2031,
 	0x101e: 0x203b, 0x101f: 0x25d4, 0x1020: 0x25e2, 0x1021: 0x1da2, 0x1022: 0x1dac, 0x1023: 0x1dd4,
 	0x1024: 0x1dde, 0x1025: 0x1dfc, 0x1026: 0x1e06, 0x1027: 0x1e6a, 0x1028: 0x1e6f, 0x1029: 0x1e92,
 	0x102a: 0x1e97, 0x102b: 0x1f6e, 0x102c: 0x1f73, 0x102d: 0x1f96, 0x102e: 0x1fe6, 0x102f: 0x1ff0,
-	0x1030: 0x2031, 0x1031: 0x203b, 0x1032: 0x459a, 0x1033: 0x45a2, 0x1034: 0x45aa, 0x1035: 0x1ef1,
+	0x1030: 0x2031, 0x1031: 0x203b, 0x1032: 0x4504, 0x1033: 0x450c, 0x1034: 0x4514, 0x1035: 0x1ef1,
 	0x1036: 0x1ef6, 0x1037: 0x1f0a, 0x1038: 0x1f0f, 0x1039: 0x1f1e, 0x103a: 0x1f23, 0x103b: 0x1e74,
 	0x103c: 0x1e79, 0x103d: 0x1e9c, 0x103e: 0x1ea1, 0x103f: 0x1e33,
 	// Block 0x41, offset 0x1040
@@ -5245,7 +5251,7 @@
 	0x106a: 0x1e65, 0x106b: 0x1eb0, 0x106c: 0x1ed3, 0x106d: 0x1e7e, 0x106e: 0x1e83, 0x106f: 0x1e88,
 	0x1070: 0x1e92, 0x1071: 0x1e6f, 0x1072: 0x1e97, 0x1073: 0x1eec, 0x1074: 0x1e56, 0x1075: 0x1e5b,
 	0x1076: 0x1e60, 0x1077: 0x1e7e, 0x1078: 0x1e83, 0x1079: 0x1e88, 0x107a: 0x1eec, 0x107b: 0x1efb,
-	0x107c: 0x449e, 0x107d: 0x449e,
+	0x107c: 0x4408, 0x107d: 0x4408,
 	// Block 0x42, offset 0x1080
 	0x1090: 0x2311, 0x1091: 0x2326,
 	0x1092: 0x2326, 0x1093: 0x232d, 0x1094: 0x2334, 0x1095: 0x2349, 0x1096: 0x2350, 0x1097: 0x2357,
@@ -5293,13 +5299,13 @@
 	0x119e: 0x04bb, 0x119f: 0x0007, 0x11a0: 0x000d, 0x11a1: 0x0015, 0x11a2: 0x0017, 0x11a3: 0x001b,
 	0x11a4: 0x0039, 0x11a5: 0x003d, 0x11a6: 0x003b, 0x11a8: 0x0079, 0x11a9: 0x0009,
 	0x11aa: 0x000b, 0x11ab: 0x0041,
-	0x11b0: 0x42aa, 0x11b1: 0x44c2, 0x11b2: 0x42af, 0x11b4: 0x42b4,
-	0x11b6: 0x42b9, 0x11b7: 0x44c8, 0x11b8: 0x42be, 0x11b9: 0x44ce, 0x11ba: 0x42c3, 0x11bb: 0x44d4,
-	0x11bc: 0x42c8, 0x11bd: 0x44da, 0x11be: 0x42cd, 0x11bf: 0x44e0,
+	0x11b0: 0x42aa, 0x11b1: 0x442c, 0x11b2: 0x42af, 0x11b4: 0x42b4,
+	0x11b6: 0x42b9, 0x11b7: 0x4432, 0x11b8: 0x42be, 0x11b9: 0x4438, 0x11ba: 0x42c3, 0x11bb: 0x443e,
+	0x11bc: 0x42c8, 0x11bd: 0x4444, 0x11be: 0x42cd, 0x11bf: 0x444a,
 	// Block 0x47, offset 0x11c0
-	0x11c0: 0x0236, 0x11c1: 0x44a4, 0x11c2: 0x44a4, 0x11c3: 0x44aa, 0x11c4: 0x44aa, 0x11c5: 0x44ec,
-	0x11c6: 0x44ec, 0x11c7: 0x44b0, 0x11c8: 0x44b0, 0x11c9: 0x44f8, 0x11ca: 0x44f8, 0x11cb: 0x44f8,
-	0x11cc: 0x44f8, 0x11cd: 0x0239, 0x11ce: 0x0239, 0x11cf: 0x023c, 0x11d0: 0x023c, 0x11d1: 0x023c,
+	0x11c0: 0x0236, 0x11c1: 0x440e, 0x11c2: 0x440e, 0x11c3: 0x4414, 0x11c4: 0x4414, 0x11c5: 0x4456,
+	0x11c6: 0x4456, 0x11c7: 0x441a, 0x11c8: 0x441a, 0x11c9: 0x4462, 0x11ca: 0x4462, 0x11cb: 0x4462,
+	0x11cc: 0x4462, 0x11cd: 0x0239, 0x11ce: 0x0239, 0x11cf: 0x023c, 0x11d0: 0x023c, 0x11d1: 0x023c,
 	0x11d2: 0x023c, 0x11d3: 0x023f, 0x11d4: 0x023f, 0x11d5: 0x0242, 0x11d6: 0x0242, 0x11d7: 0x0242,
 	0x11d8: 0x0242, 0x11d9: 0x0245, 0x11da: 0x0245, 0x11db: 0x0245, 0x11dc: 0x0245, 0x11dd: 0x0248,
 	0x11de: 0x0248, 0x11df: 0x0248, 0x11e0: 0x0248, 0x11e1: 0x024b, 0x11e2: 0x024b, 0x11e3: 0x024b,
@@ -5338,18 +5344,18 @@
 	0x128c: 0x054b, 0x128d: 0x054f, 0x128e: 0x0553, 0x128f: 0x0557, 0x1290: 0x055b, 0x1291: 0x055f,
 	0x1292: 0x0563, 0x1293: 0x0567, 0x1294: 0x056f, 0x1295: 0x0577, 0x1296: 0x057f, 0x1297: 0x0583,
 	0x1298: 0x0587, 0x1299: 0x058b, 0x129a: 0x058f, 0x129b: 0x0593, 0x129c: 0x0597, 0x129d: 0x05a7,
-	0x129e: 0x4a5a, 0x129f: 0x4a60, 0x12a0: 0x03c3, 0x12a1: 0x0313, 0x12a2: 0x0317, 0x12a3: 0x4345,
-	0x12a4: 0x031b, 0x12a5: 0x434a, 0x12a6: 0x434f, 0x12a7: 0x031f, 0x12a8: 0x0323, 0x12a9: 0x0327,
-	0x12aa: 0x4354, 0x12ab: 0x4359, 0x12ac: 0x435e, 0x12ad: 0x4363, 0x12ae: 0x4368, 0x12af: 0x436d,
+	0x129e: 0x4a78, 0x129f: 0x4a7e, 0x12a0: 0x03c3, 0x12a1: 0x0313, 0x12a2: 0x0317, 0x12a3: 0x4a3b,
+	0x12a4: 0x031b, 0x12a5: 0x4a41, 0x12a6: 0x4a47, 0x12a7: 0x031f, 0x12a8: 0x0323, 0x12a9: 0x0327,
+	0x12aa: 0x4a4d, 0x12ab: 0x4a53, 0x12ac: 0x4a59, 0x12ad: 0x4a5f, 0x12ae: 0x4a65, 0x12af: 0x4a6b,
 	0x12b0: 0x0367, 0x12b1: 0x032b, 0x12b2: 0x032f, 0x12b3: 0x0333, 0x12b4: 0x037b, 0x12b5: 0x0337,
 	0x12b6: 0x033b, 0x12b7: 0x033f, 0x12b8: 0x0343, 0x12b9: 0x0347, 0x12ba: 0x034b, 0x12bb: 0x034f,
 	0x12bc: 0x0353, 0x12bd: 0x0357, 0x12be: 0x035b,
 	// Block 0x4b, offset 0x12c0
-	0x12c2: 0x42dc, 0x12c3: 0x42e1, 0x12c4: 0x42e6, 0x12c5: 0x42eb,
-	0x12c6: 0x42f0, 0x12c7: 0x42f5, 0x12ca: 0x42fa, 0x12cb: 0x42ff,
-	0x12cc: 0x4304, 0x12cd: 0x4309, 0x12ce: 0x430e, 0x12cf: 0x4313,
-	0x12d2: 0x4318, 0x12d3: 0x431d, 0x12d4: 0x4322, 0x12d5: 0x4327, 0x12d6: 0x432c, 0x12d7: 0x4331,
-	0x12da: 0x4336, 0x12db: 0x433b, 0x12dc: 0x4340,
+	0x12c2: 0x49bd, 0x12c3: 0x49c3, 0x12c4: 0x49c9, 0x12c5: 0x49cf,
+	0x12c6: 0x49d5, 0x12c7: 0x49db, 0x12ca: 0x49e1, 0x12cb: 0x49e7,
+	0x12cc: 0x49ed, 0x12cd: 0x49f3, 0x12ce: 0x49f9, 0x12cf: 0x49ff,
+	0x12d2: 0x4a05, 0x12d3: 0x4a0b, 0x12d4: 0x4a11, 0x12d5: 0x4a17, 0x12d6: 0x4a1d, 0x12d7: 0x4a23,
+	0x12da: 0x4a29, 0x12db: 0x4a2f, 0x12dc: 0x4a35,
 	0x12e0: 0x00bf, 0x12e1: 0x00c2, 0x12e2: 0x00cb, 0x12e3: 0x4264,
 	0x12e4: 0x00c8, 0x12e5: 0x00c5, 0x12e6: 0x0447, 0x12e8: 0x046b, 0x12e9: 0x044b,
 	0x12ea: 0x044f, 0x12eb: 0x0453, 0x12ec: 0x0457, 0x12ed: 0x046f, 0x12ee: 0x0473,
@@ -5426,7 +5432,7 @@
 	// Block 0x52, offset 0x1480
 	0x1480: 0x26ad, 0x1481: 0x26c2, 0x1482: 0x0503,
 	0x1490: 0x0c0f, 0x1491: 0x0a47,
-	0x1492: 0x08d3, 0x1493: 0x465a, 0x1494: 0x071b, 0x1495: 0x09ef, 0x1496: 0x132f, 0x1497: 0x09ff,
+	0x1492: 0x08d3, 0x1493: 0x45c4, 0x1494: 0x071b, 0x1495: 0x09ef, 0x1496: 0x132f, 0x1497: 0x09ff,
 	0x1498: 0x0727, 0x1499: 0x0cd7, 0x149a: 0x0eaf, 0x149b: 0x0caf, 0x149c: 0x0827, 0x149d: 0x0b6b,
 	0x149e: 0x07bf, 0x149f: 0x0cb7, 0x14a0: 0x0813, 0x14a1: 0x1117, 0x14a2: 0x0f83, 0x14a3: 0x138b,
 	0x14a4: 0x09d3, 0x14a5: 0x090b, 0x14a6: 0x0e63, 0x14a7: 0x0c1b, 0x14a8: 0x0c47, 0x14a9: 0x06bf,
@@ -5665,8 +5671,8 @@
 	{value: 0x22b2, lo: 0xbe, hi: 0xbe},
 	// Block 0x1, offset 0xe
 	{value: 0x0091, lo: 0x03},
-	{value: 0x4778, lo: 0xa0, hi: 0xa1},
-	{value: 0x47aa, lo: 0xaf, hi: 0xb0},
+	{value: 0x46e2, lo: 0xa0, hi: 0xa1},
+	{value: 0x4714, lo: 0xaf, hi: 0xb0},
 	{value: 0xa000, lo: 0xb7, hi: 0xb7},
 	// Block 0x2, offset 0x12
 	{value: 0x0003, lo: 0x08},
@@ -5814,7 +5820,7 @@
 	{value: 0x812d, lo: 0x92, hi: 0x92},
 	{value: 0x8132, lo: 0x93, hi: 0x93},
 	{value: 0x8132, lo: 0x94, hi: 0x94},
-	{value: 0x45b2, lo: 0x98, hi: 0x9f},
+	{value: 0x451c, lo: 0x98, hi: 0x9f},
 	// Block 0x11, offset 0x96
 	{value: 0x0000, lo: 0x02},
 	{value: 0x8102, lo: 0xbc, hi: 0xbc},
@@ -5825,18 +5831,18 @@
 	{value: 0x2c9e, lo: 0x8b, hi: 0x8c},
 	{value: 0x8104, lo: 0x8d, hi: 0x8d},
 	{value: 0x9900, lo: 0x97, hi: 0x97},
-	{value: 0x45f2, lo: 0x9c, hi: 0x9d},
-	{value: 0x4602, lo: 0x9f, hi: 0x9f},
+	{value: 0x455c, lo: 0x9c, hi: 0x9d},
+	{value: 0x456c, lo: 0x9f, hi: 0x9f},
 	// Block 0x13, offset 0xa0
 	{value: 0x0000, lo: 0x03},
-	{value: 0x462a, lo: 0xb3, hi: 0xb3},
-	{value: 0x4632, lo: 0xb6, hi: 0xb6},
+	{value: 0x4594, lo: 0xb3, hi: 0xb3},
+	{value: 0x459c, lo: 0xb6, hi: 0xb6},
 	{value: 0x8102, lo: 0xbc, hi: 0xbc},
 	// Block 0x14, offset 0xa4
 	{value: 0x0008, lo: 0x03},
 	{value: 0x8104, lo: 0x8d, hi: 0x8d},
-	{value: 0x460a, lo: 0x99, hi: 0x9b},
-	{value: 0x4622, lo: 0x9e, hi: 0x9e},
+	{value: 0x4574, lo: 0x99, hi: 0x9b},
+	{value: 0x458c, lo: 0x9e, hi: 0x9e},
 	// Block 0x15, offset 0xa8
 	{value: 0x0000, lo: 0x01},
 	{value: 0x8102, lo: 0xbc, hi: 0xbc},
@@ -5851,8 +5857,8 @@
 	{value: 0x2cbe, lo: 0x8c, hi: 0x8c},
 	{value: 0x8104, lo: 0x8d, hi: 0x8d},
 	{value: 0x9900, lo: 0x96, hi: 0x97},
-	{value: 0x463a, lo: 0x9c, hi: 0x9c},
-	{value: 0x4642, lo: 0x9d, hi: 0x9d},
+	{value: 0x45a4, lo: 0x9c, hi: 0x9c},
+	{value: 0x45ac, lo: 0x9d, hi: 0x9d},
 	// Block 0x18, offset 0xb5
 	{value: 0x0000, lo: 0x03},
 	{value: 0xa000, lo: 0x92, hi: 0x92},
@@ -5941,18 +5947,18 @@
 	{value: 0x263d, lo: 0xa9, hi: 0xa9},
 	{value: 0x8126, lo: 0xb1, hi: 0xb1},
 	{value: 0x8127, lo: 0xb2, hi: 0xb2},
-	{value: 0x4a66, lo: 0xb3, hi: 0xb3},
+	{value: 0x4a84, lo: 0xb3, hi: 0xb3},
 	{value: 0x8128, lo: 0xb4, hi: 0xb4},
-	{value: 0x4a6f, lo: 0xb5, hi: 0xb5},
-	{value: 0x464a, lo: 0xb6, hi: 0xb6},
-	{value: 0x468a, lo: 0xb7, hi: 0xb7},
-	{value: 0x4652, lo: 0xb8, hi: 0xb8},
-	{value: 0x4695, lo: 0xb9, hi: 0xb9},
+	{value: 0x4a8d, lo: 0xb5, hi: 0xb5},
+	{value: 0x45b4, lo: 0xb6, hi: 0xb6},
+	{value: 0x45f4, lo: 0xb7, hi: 0xb7},
+	{value: 0x45bc, lo: 0xb8, hi: 0xb8},
+	{value: 0x45ff, lo: 0xb9, hi: 0xb9},
 	{value: 0x8127, lo: 0xba, hi: 0xbd},
 	// Block 0x26, offset 0x107
 	{value: 0x0000, lo: 0x0b},
 	{value: 0x8127, lo: 0x80, hi: 0x80},
-	{value: 0x4a78, lo: 0x81, hi: 0x81},
+	{value: 0x4a96, lo: 0x81, hi: 0x81},
 	{value: 0x8132, lo: 0x82, hi: 0x83},
 	{value: 0x8104, lo: 0x84, hi: 0x84},
 	{value: 0x8132, lo: 0x86, hi: 0x87},
@@ -6199,7 +6205,7 @@
 	{value: 0x192d, lo: 0xb5, hi: 0xb6},
 	// Block 0x4a, offset 0x1db
 	{value: 0x0000, lo: 0x01},
-	{value: 0x4573, lo: 0x9c, hi: 0x9c},
+	{value: 0x44dd, lo: 0x9c, hi: 0x9c},
 	// Block 0x4b, offset 0x1dd
 	{value: 0x0000, lo: 0x02},
 	{value: 0x0095, lo: 0xbc, hi: 0xbc},
@@ -6245,16 +6251,16 @@
 	{value: 0x04b3, lo: 0xb6, hi: 0xb6},
 	{value: 0x0887, lo: 0xb8, hi: 0xba},
 	// Block 0x53, offset 0x201
-	{value: 0x0005, lo: 0x09},
+	{value: 0x0006, lo: 0x09},
 	{value: 0x0313, lo: 0xb1, hi: 0xb1},
 	{value: 0x0317, lo: 0xb2, hi: 0xb2},
-	{value: 0x4345, lo: 0xb3, hi: 0xb3},
+	{value: 0x4a3b, lo: 0xb3, hi: 0xb3},
 	{value: 0x031b, lo: 0xb4, hi: 0xb4},
-	{value: 0x434a, lo: 0xb5, hi: 0xb6},
+	{value: 0x4a41, lo: 0xb5, hi: 0xb6},
 	{value: 0x031f, lo: 0xb7, hi: 0xb7},
 	{value: 0x0323, lo: 0xb8, hi: 0xb8},
 	{value: 0x0327, lo: 0xb9, hi: 0xb9},
-	{value: 0x4354, lo: 0xba, hi: 0xbf},
+	{value: 0x4a4d, lo: 0xba, hi: 0xbf},
 	// Block 0x54, offset 0x20b
 	{value: 0x0000, lo: 0x02},
 	{value: 0x8132, lo: 0xaf, hi: 0xaf},
@@ -6479,13 +6485,13 @@
 	{value: 0x8101, lo: 0x9e, hi: 0x9e},
 	// Block 0x83, offset 0x2ba
 	{value: 0x0000, lo: 0x0c},
-	{value: 0x4662, lo: 0x9e, hi: 0x9e},
-	{value: 0x466c, lo: 0x9f, hi: 0x9f},
-	{value: 0x46a0, lo: 0xa0, hi: 0xa0},
-	{value: 0x46ae, lo: 0xa1, hi: 0xa1},
-	{value: 0x46bc, lo: 0xa2, hi: 0xa2},
-	{value: 0x46ca, lo: 0xa3, hi: 0xa3},
-	{value: 0x46d8, lo: 0xa4, hi: 0xa4},
+	{value: 0x45cc, lo: 0x9e, hi: 0x9e},
+	{value: 0x45d6, lo: 0x9f, hi: 0x9f},
+	{value: 0x460a, lo: 0xa0, hi: 0xa0},
+	{value: 0x4618, lo: 0xa1, hi: 0xa1},
+	{value: 0x4626, lo: 0xa2, hi: 0xa2},
+	{value: 0x4634, lo: 0xa3, hi: 0xa3},
+	{value: 0x4642, lo: 0xa4, hi: 0xa4},
 	{value: 0x812b, lo: 0xa5, hi: 0xa6},
 	{value: 0x8101, lo: 0xa7, hi: 0xa9},
 	{value: 0x8130, lo: 0xad, hi: 0xad},
@@ -6497,14 +6503,14 @@
 	{value: 0x8132, lo: 0x85, hi: 0x89},
 	{value: 0x812d, lo: 0x8a, hi: 0x8b},
 	{value: 0x8132, lo: 0xaa, hi: 0xad},
-	{value: 0x4676, lo: 0xbb, hi: 0xbb},
-	{value: 0x4680, lo: 0xbc, hi: 0xbc},
-	{value: 0x46e6, lo: 0xbd, hi: 0xbd},
-	{value: 0x4702, lo: 0xbe, hi: 0xbe},
-	{value: 0x46f4, lo: 0xbf, hi: 0xbf},
+	{value: 0x45e0, lo: 0xbb, hi: 0xbb},
+	{value: 0x45ea, lo: 0xbc, hi: 0xbc},
+	{value: 0x4650, lo: 0xbd, hi: 0xbd},
+	{value: 0x466c, lo: 0xbe, hi: 0xbe},
+	{value: 0x465e, lo: 0xbf, hi: 0xbf},
 	// Block 0x85, offset 0x2d1
 	{value: 0x0000, lo: 0x01},
-	{value: 0x4710, lo: 0x80, hi: 0x80},
+	{value: 0x467a, lo: 0x80, hi: 0x80},
 	// Block 0x86, offset 0x2d3
 	{value: 0x0000, lo: 0x01},
 	{value: 0x8132, lo: 0x82, hi: 0x84},
@@ -7624,4 +7630,4 @@
 	0x15B915AF: 0x115BB,
 }
 
-// Total size of tables: 53KB (53976 bytes)
+// Total size of tables: 53KB (54006 bytes)
diff --git a/libgo/go/golang_org/x/text/unicode/norm/transform.go b/libgo/go/golang_org/x/text/unicode/norm/transform.go
index b341789..4dec306 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/transform.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/transform.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2013 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
diff --git a/libgo/go/golang_org/x/text/unicode/norm/trie.go b/libgo/go/golang_org/x/text/unicode/norm/trie.go
index 423386b..4cbea64 100644
--- a/libgo/go/golang_org/x/text/unicode/norm/trie.go
+++ b/libgo/go/golang_org/x/text/unicode/norm/trie.go
@@ -1,3 +1,5 @@
+// Code generated by running "go run gen.go -core" in golang.org/x/text. DO NOT EDIT.
+
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
diff --git a/libgo/go/hash/crc32/crc32_amd64.go b/libgo/go/hash/crc32/crc32_amd64.go
index 72844f0..b394fc0 100644
--- a/libgo/go/hash/crc32/crc32_amd64.go
+++ b/libgo/go/hash/crc32/crc32_amd64.go
@@ -10,23 +10,20 @@
 
 package crc32
 
-import "unsafe"
+import (
+	"internal/cpu"
+	"unsafe"
+)
 
 // This file contains the code to call the SSE 4.2 version of the Castagnoli
 // and IEEE CRC.
 
-// haveSSE41/haveSSE42/haveCLMUL are defined in crc_amd64.s and use
-// CPUID to test for SSE 4.1, 4.2 and CLMUL support.
-func haveSSE41() bool
-func haveSSE42() bool
-func haveCLMUL() bool
-
-// castagnoliSSE42 is defined in crc32_amd64.s and uses the SSE4.2 CRC32
+// castagnoliSSE42 is defined in crc32_amd64.s and uses the SSE 4.2 CRC32
 // instruction.
 //go:noescape
 func castagnoliSSE42(crc uint32, p []byte) uint32
 
-// castagnoliSSE42Triple is defined in crc32_amd64.s and uses the SSE4.2 CRC32
+// castagnoliSSE42Triple is defined in crc32_amd64.s and uses the SSE 4.2 CRC32
 // instruction.
 //go:noescape
 func castagnoliSSE42Triple(
@@ -40,9 +37,6 @@
 //go:noescape
 func ieeeCLMUL(crc uint32, p []byte) uint32
 
-var sse42 = haveSSE42()
-var useFastIEEE = haveCLMUL() && haveSSE41()
-
 const castagnoliK1 = 168
 const castagnoliK2 = 1344
 
@@ -52,11 +46,11 @@
 var castagnoliSSE42TableK2 *sse42Table
 
 func archAvailableCastagnoli() bool {
-	return sse42
+	return cpu.X86.HasSSE42
 }
 
 func archInitCastagnoli() {
-	if !sse42 {
+	if !cpu.X86.HasSSE42 {
 		panic("arch-specific Castagnoli not available")
 	}
 	castagnoliSSE42TableK1 = new(sse42Table)
@@ -88,7 +82,7 @@
 }
 
 func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
-	if !sse42 {
+	if !cpu.X86.HasSSE42 {
 		panic("not available")
 	}
 
@@ -199,13 +193,13 @@
 }
 
 func archAvailableIEEE() bool {
-	return useFastIEEE
+	return cpu.X86.HasPCLMULQDQ && cpu.X86.HasSSE41
 }
 
 var archIeeeTable8 *slicing8Table
 
 func archInitIEEE() {
-	if !useFastIEEE {
+	if !cpu.X86.HasPCLMULQDQ || !cpu.X86.HasSSE41 {
 		panic("not available")
 	}
 	// We still use slicing-by-8 for small buffers.
@@ -213,7 +207,7 @@
 }
 
 func archUpdateIEEE(crc uint32, p []byte) uint32 {
-	if !useFastIEEE {
+	if !cpu.X86.HasPCLMULQDQ || !cpu.X86.HasSSE41 {
 		panic("not available")
 	}
 
diff --git a/libgo/go/hash/crc32/crc32_amd64p32.go b/libgo/go/hash/crc32/crc32_amd64p32.go
index 9d728fc..1ec44cb 100644
--- a/libgo/go/hash/crc32/crc32_amd64p32.go
+++ b/libgo/go/hash/crc32/crc32_amd64p32.go
@@ -4,33 +4,29 @@
 
 package crc32
 
+import "internal/cpu"
+
 // This file contains the code to call the SSE 4.2 version of the Castagnoli
 // CRC.
 
-// haveSSE42 is defined in crc32_amd64p32.s and uses CPUID to test for SSE 4.2
-// support.
-func haveSSE42() bool
-
 // castagnoliSSE42 is defined in crc32_amd64p32.s and uses the SSE4.2 CRC32
 // instruction.
 //go:noescape
 func castagnoliSSE42(crc uint32, p []byte) uint32
 
-var sse42 = haveSSE42()
-
 func archAvailableCastagnoli() bool {
-	return sse42
+	return cpu.X86.HasSSE42
 }
 
 func archInitCastagnoli() {
-	if !sse42 {
+	if !cpu.X86.HasSSE42 {
 		panic("not available")
 	}
 	// No initialization necessary.
 }
 
 func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
-	if !sse42 {
+	if !cpu.X86.HasSSE42 {
 		panic("not available")
 	}
 	return castagnoliSSE42(crc, p)
diff --git a/libgo/go/hash/crc32/crc32_arm64.go b/libgo/go/hash/crc32/crc32_arm64.go
new file mode 100644
index 0000000..4c5cad1
--- /dev/null
+++ b/libgo/go/hash/crc32/crc32_arm64.go
@@ -0,0 +1,53 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// ARM64-specific hardware-assisted CRC32 algorithms. See crc32.go for a
+// description of the interface that each architecture-specific file
+// implements.
+
+package crc32
+
+func supportsCRC32() bool
+func castagnoliUpdate(crc uint32, p []byte) uint32
+func ieeeUpdate(crc uint32, p []byte) uint32
+
+var hasCRC32 = supportsCRC32()
+
+func archAvailableCastagnoli() bool {
+	return hasCRC32
+}
+
+func archInitCastagnoli() {
+	if !hasCRC32 {
+		panic("arch-specific crc32 instruction for Catagnoli not available")
+	}
+}
+
+func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
+	if !hasCRC32 {
+		panic("arch-specific crc32 instruction for Castagnoli not available")
+	}
+
+	return ^castagnoliUpdate(^crc, p)
+}
+
+func archAvailableIEEE() bool {
+	return hasCRC32
+}
+
+func archInitIEEE() {
+	if !hasCRC32 {
+		panic("arch-specific crc32 instruction for IEEE not available")
+	}
+}
+
+func archUpdateIEEE(crc uint32, p []byte) uint32 {
+	if !hasCRC32 {
+		panic("arch-specific crc32 instruction for IEEE not available")
+	}
+
+	return ^ieeeUpdate(^crc, p)
+}
diff --git a/libgo/go/hash/crc32/crc32_otherarch.go b/libgo/go/hash/crc32/crc32_otherarch.go
index 09c3389..c3acd25 100644
--- a/libgo/go/hash/crc32/crc32_otherarch.go
+++ b/libgo/go/hash/crc32/crc32_otherarch.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// -build !amd64,!amd64p32,!s390x
+// -build !amd64,!amd64p32,!s390x,!ppc64le,!arm64
 
 package crc32
 
diff --git a/libgo/go/hash/crc32/crc32_ppc64le.go b/libgo/go/hash/crc32/crc32_ppc64le.go
new file mode 100644
index 0000000..4211b5b
--- /dev/null
+++ b/libgo/go/hash/crc32/crc32_ppc64le.go
@@ -0,0 +1,89 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package crc32
+
+import (
+	"unsafe"
+)
+
+const (
+	vecMinLen    = 16
+	vecAlignMask = 15 // align to 16 bytes
+	crcIEEE      = 1
+	crcCast      = 2
+)
+
+//go:noescape
+func ppc64SlicingUpdateBy8(crc uint32, table8 *slicing8Table, p []byte) uint32
+
+// this function requires the buffer to be 16 byte aligned and > 16 bytes long
+//go:noescape
+func vectorCrc32(crc uint32, poly uint32, p []byte) uint32
+
+var archCastagnoliTable8 *slicing8Table
+
+func archInitCastagnoli() {
+	archCastagnoliTable8 = slicingMakeTable(Castagnoli)
+}
+
+func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
+	if len(p) >= 4*vecMinLen {
+		// If not aligned then process the initial unaligned bytes
+
+		if uint64(uintptr(unsafe.Pointer(&p[0])))&uint64(vecAlignMask) != 0 {
+			align := uint64(uintptr(unsafe.Pointer(&p[0]))) & uint64(vecAlignMask)
+			newlen := vecMinLen - align
+			crc = ppc64SlicingUpdateBy8(crc, archCastagnoliTable8, p[:newlen])
+			p = p[newlen:]
+		}
+		// p should be aligned now
+		aligned := len(p) & ^vecAlignMask
+		crc = vectorCrc32(crc, crcCast, p[:aligned])
+		p = p[aligned:]
+	}
+	if len(p) == 0 {
+		return crc
+	}
+	return ppc64SlicingUpdateBy8(crc, archCastagnoliTable8, p)
+}
+
+func archAvailableIEEE() bool {
+	return true
+}
+func archAvailableCastagnoli() bool {
+	return true
+}
+
+var archIeeeTable8 *slicing8Table
+
+func archInitIEEE() {
+	// We still use slicing-by-8 for small buffers.
+	archIeeeTable8 = slicingMakeTable(IEEE)
+}
+
+// archUpdateIEEE calculates the checksum of p using vectorizedIEEE.
+func archUpdateIEEE(crc uint32, p []byte) uint32 {
+
+	// Check if vector code should be used.  If not aligned, then handle those
+	// first up to the aligned bytes.
+
+	if len(p) >= 4*vecMinLen {
+		if uint64(uintptr(unsafe.Pointer(&p[0])))&uint64(vecAlignMask) != 0 {
+			align := uint64(uintptr(unsafe.Pointer(&p[0]))) & uint64(vecAlignMask)
+			newlen := vecMinLen - align
+			crc = ppc64SlicingUpdateBy8(crc, archIeeeTable8, p[:newlen])
+			p = p[newlen:]
+		}
+		aligned := len(p) & ^vecAlignMask
+		crc = vectorCrc32(crc, crcIEEE, p[:aligned])
+		p = p[aligned:]
+	}
+	if len(p) == 0 {
+		return crc
+	}
+	return ppc64SlicingUpdateBy8(crc, archIeeeTable8, p)
+}
diff --git a/libgo/go/hash/crc32/crc32_test.go b/libgo/go/hash/crc32/crc32_test.go
index 1356734..0492f46 100644
--- a/libgo/go/hash/crc32/crc32_test.go
+++ b/libgo/go/hash/crc32/crc32_test.go
@@ -5,6 +5,7 @@
 package crc32
 
 import (
+	"fmt"
 	"hash"
 	"math/rand"
 	"testing"
@@ -75,8 +76,9 @@
 	// The AMD64 implementation has some cutoffs at lengths 168*3=504 and
 	// 1344*3=4032. We should make sure lengths around these values are in the
 	// list.
-	lengths := []int{0, 1, 2, 3, 4, 5, 10, 16, 50, 100, 128,
-		500, 501, 502, 503, 504, 505, 512, 1000, 1024, 2000,
+	lengths := []int{0, 1, 2, 3, 4, 5, 10, 16, 50, 63, 64, 65, 100,
+		127, 128, 129, 255, 256, 257, 300, 312, 384, 416, 448, 480,
+		500, 501, 502, 503, 504, 505, 512, 513, 1000, 1024, 2000,
 		4030, 4031, 4032, 4033, 4036, 4040, 4048, 4096, 5000, 10000}
 	for _, length := range lengths {
 		p := make([]byte, length)
@@ -196,68 +198,28 @@
 	}
 }
 
-func BenchmarkIEEECrc40B(b *testing.B) {
-	benchmark(b, NewIEEE(), 40, 0)
+func BenchmarkCRC32(b *testing.B) {
+	b.Run("poly=IEEE", benchmarkAll(NewIEEE()))
+	b.Run("poly=Castagnoli", benchmarkAll(New(MakeTable(Castagnoli))))
+	b.Run("poly=Koopman", benchmarkAll(New(MakeTable(Koopman))))
 }
 
-func BenchmarkIEEECrc1KB(b *testing.B) {
-	benchmark(b, NewIEEE(), 1<<10, 0)
-}
-
-func BenchmarkIEEECrc4KB(b *testing.B) {
-	benchmark(b, NewIEEE(), 4<<10, 0)
-}
-
-func BenchmarkIEEECrc32KB(b *testing.B) {
-	benchmark(b, NewIEEE(), 32<<10, 0)
-}
-
-func BenchmarkCastagnoliCrc15B(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 15, 0)
-}
-
-func BenchmarkCastagnoliCrc15BMisaligned(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 15, 1)
-}
-
-func BenchmarkCastagnoliCrc40B(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 40, 0)
-}
-
-func BenchmarkCastagnoliCrc40BMisaligned(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 40, 1)
-}
-
-func BenchmarkCastagnoliCrc512(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 512, 0)
-}
-
-func BenchmarkCastagnoliCrc512Misaligned(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 512, 1)
-}
-
-func BenchmarkCastagnoliCrc1KB(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 1<<10, 0)
-}
-
-func BenchmarkCastagnoliCrc1KBMisaligned(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 1<<10, 1)
-}
-
-func BenchmarkCastagnoliCrc4KB(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 4<<10, 0)
-}
-
-func BenchmarkCastagnoliCrc4KBMisaligned(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 4<<10, 1)
-}
-
-func BenchmarkCastagnoliCrc32KB(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 32<<10, 0)
-}
-
-func BenchmarkCastagnoliCrc32KBMisaligned(b *testing.B) {
-	benchmark(b, New(MakeTable(Castagnoli)), 32<<10, 1)
+func benchmarkAll(h hash.Hash32) func(b *testing.B) {
+	return func(b *testing.B) {
+		for _, size := range []int{15, 40, 512, 1 << 10, 4 << 10, 32 << 10} {
+			name := fmt.Sprint(size)
+			if size >= 1024 {
+				name = fmt.Sprintf("%dkB", size/1024)
+			}
+			b.Run("size="+name, func(b *testing.B) {
+				for align := 0; align <= 1; align++ {
+					b.Run(fmt.Sprintf("align=%d", align), func(b *testing.B) {
+						benchmark(b, h, int64(size), int64(align))
+					})
+				}
+			})
+		}
+	}
 }
 
 func benchmark(b *testing.B, h hash.Hash32, n, alignment int64) {
diff --git a/libgo/go/hash/crc32/gen_const_ppc64le.go b/libgo/go/hash/crc32/gen_const_ppc64le.go
new file mode 100644
index 0000000..bfb3b3a
--- /dev/null
+++ b/libgo/go/hash/crc32/gen_const_ppc64le.go
@@ -0,0 +1,150 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// Generate the constant table associated with the poly used by the
+// vpmsumd crc32 algorithm.
+//
+// go run gen_const_ppc64le.go
+//
+// generates crc32_table_ppc64le.s
+
+// The following is derived from code written by Anton Blanchard
+// <anton@au.ibm.com> found at https://github.com/antonblanchard/crc32-vpmsum.
+// The original is dual licensed under GPL and Apache 2.  As the copyright holder
+// for the work, IBM has contributed this new work under the golang license.
+
+// This code was written in Go based on the original C implementation.
+
+// This is a tool needed to generate the appropriate constants needed for
+// the vpmsum algorithm.  It is included to generate new constant tables if
+// new polynomial values are included in the future.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+)
+
+var blocking = 32 * 1024
+
+func reflect_bits(b uint64, nr uint) uint64 {
+	var ref uint64
+
+	for bit := uint64(0); bit < uint64(nr); bit++ {
+		if (b & uint64(1)) == 1 {
+			ref |= (1 << (uint64(nr-1) - bit))
+		}
+		b = (b >> 1)
+	}
+	return ref
+}
+
+func get_remainder(poly uint64, deg uint, n uint) uint64 {
+
+	rem, _ := xnmodp(n, poly, deg)
+	return rem
+}
+
+func get_quotient(poly uint64, bits, n uint) uint64 {
+
+	_, div := xnmodp(n, poly, bits)
+	return div
+}
+
+// xnmodp returns two values, p and div:
+// p is the representation of the binary polynomial x**n mod (x ** deg + "poly")
+// That is p is the binary representation of the modulus polynomial except for its highest-order term.
+// div is the binary representation of the polynomial x**n / (x ** deg + "poly")
+func xnmodp(n uint, poly uint64, deg uint) (uint64, uint64) {
+
+	var mod, mask, high, div uint64
+
+	if n < deg {
+		div = 0
+		return poly, div
+	}
+	mask = 1<<deg - 1
+	poly &= mask
+	mod = poly
+	div = 1
+	deg--
+	n--
+	for n > deg {
+		high = (mod >> deg) & 1
+		div = (div << 1) | high
+		mod <<= 1
+		if high != 0 {
+			mod ^= poly
+		}
+		n--
+	}
+	return mod & mask, div
+}
+
+func main() {
+	w := new(bytes.Buffer)
+
+	fmt.Fprintf(w, "// autogenerated: do not edit!\n")
+	fmt.Fprintf(w, "// generated from crc32/gen_const_ppc64le.go\n")
+	fmt.Fprintln(w)
+	fmt.Fprintf(w, "#include \"textflag.h\"\n")
+
+	// These are the polynomials supported in vector now.
+	// If adding others, include the polynomial and a name
+	// to identify it.
+
+	genCrc32ConstTable(w, 0xedb88320, "IEEE")
+	genCrc32ConstTable(w, 0x82f63b78, "Cast")
+	genCrc32ConstTable(w, 0xeb31d82e, "Koop")
+	b := w.Bytes()
+
+	err := ioutil.WriteFile("crc32_table_ppc64le.s", b, 0666)
+	if err != nil {
+		fmt.Printf("can't write output: %s\n", err)
+	}
+}
+
+func genCrc32ConstTable(w *bytes.Buffer, poly uint32, polyid string) {
+
+	ref_poly := reflect_bits(uint64(poly), 32)
+	fmt.Fprintf(w, "\n\t/* Reduce %d kbits to 1024 bits */\n", blocking*8)
+	j := 0
+	for i := (blocking * 8) - 1024; i > 0; i -= 1024 {
+		a := reflect_bits(get_remainder(ref_poly, 32, uint(i)), 32) << 1
+		b := reflect_bits(get_remainder(ref_poly, 32, uint(i+64)), 32) << 1
+
+		fmt.Fprintf(w, "\t/* x^%d mod p(x)%s, x^%d mod p(x)%s */\n", uint(i+64), "", uint(i), "")
+		fmt.Fprintf(w, "DATA ·%sConst+%d(SB)/8,$0x%016x\n", polyid, j*8, b)
+		fmt.Fprintf(w, "DATA ·%sConst+%d(SB)/8,$0x%016x\n", polyid, (j+1)*8, a)
+
+		j += 2
+		fmt.Fprintf(w, "\n")
+	}
+
+	for i := (1024 * 2) - 128; i >= 0; i -= 128 {
+		a := reflect_bits(get_remainder(ref_poly, 32, uint(i+32)), 32)
+		b := reflect_bits(get_remainder(ref_poly, 32, uint(i+64)), 32)
+		c := reflect_bits(get_remainder(ref_poly, 32, uint(i+96)), 32)
+		d := reflect_bits(get_remainder(ref_poly, 32, uint(i+128)), 32)
+
+		fmt.Fprintf(w, "\t/* x^%d mod p(x)%s, x^%d mod p(x)%s, x^%d mod p(x)%s, x^%d mod p(x)%s */\n", i+128, "", i+96, "", i+64, "", i+32, "")
+		fmt.Fprintf(w, "DATA ·%sConst+%d(SB)/8,$0x%08x%08x\n", polyid, j*8, c, d)
+		fmt.Fprintf(w, "DATA ·%sConst+%d(SB)/8,$0x%08x%08x\n", polyid, (j+1)*8, a, b)
+
+		j += 2
+		fmt.Fprintf(w, "\n")
+	}
+
+	fmt.Fprintf(w, "GLOBL ·%sConst(SB),RODATA,$4336\n", polyid)
+	fmt.Fprintf(w, "\n /* Barrett constant m - (4^32)/n */\n")
+	fmt.Fprintf(w, "DATA ·%sBarConst(SB)/8,$0x%016x\n", polyid, reflect_bits(get_quotient(ref_poly, 32, 64), 33))
+	fmt.Fprintf(w, "DATA ·%sBarConst+8(SB)/8,$0x0000000000000000\n", polyid)
+	fmt.Fprintf(w, "DATA ·%sBarConst+16(SB)/8,$0x%016x\n", polyid, reflect_bits((uint64(1)<<32)|ref_poly, 33)) // reflected?
+	fmt.Fprintf(w, "DATA ·%sBarConst+24(SB)/8,$0x0000000000000000\n", polyid)
+	fmt.Fprintf(w, "GLOBL ·%sBarConst(SB),RODATA,$32\n", polyid)
+}
diff --git a/libgo/go/hash/fnv/fnv.go b/libgo/go/hash/fnv/fnv.go
index f1fbb25..3d2df73 100644
--- a/libgo/go/hash/fnv/fnv.go
+++ b/libgo/go/hash/fnv/fnv.go
@@ -13,17 +13,23 @@
 )
 
 type (
-	sum32  uint32
-	sum32a uint32
-	sum64  uint64
-	sum64a uint64
+	sum32   uint32
+	sum32a  uint32
+	sum64   uint64
+	sum64a  uint64
+	sum128  [2]uint64
+	sum128a [2]uint64
 )
 
 const (
-	offset32 = 2166136261
-	offset64 = 14695981039346656037
-	prime32  = 16777619
-	prime64  = 1099511628211
+	offset32        = 2166136261
+	offset64        = 14695981039346656037
+	offset128Lower  = 0x62b821756295c58d
+	offset128Higher = 0x6c62272e07bb0142
+	prime32         = 16777619
+	prime64         = 1099511628211
+	prime128Lower   = 0x13b
+	prime128Shift   = 24
 )
 
 // New32 returns a new 32-bit FNV-1 hash.Hash.
@@ -54,10 +60,30 @@
 	return &s
 }
 
-func (s *sum32) Reset()  { *s = offset32 }
-func (s *sum32a) Reset() { *s = offset32 }
-func (s *sum64) Reset()  { *s = offset64 }
-func (s *sum64a) Reset() { *s = offset64 }
+// New128 returns a new 128-bit FNV-1 hash.Hash.
+// Its Sum method will lay the value out in big-endian byte order.
+func New128() hash.Hash {
+	var s sum128
+	s[0] = offset128Higher
+	s[1] = offset128Lower
+	return &s
+}
+
+// New128a returns a new 128-bit FNV-1a hash.Hash.
+// Its Sum method will lay the value out in big-endian byte order.
+func New128a() hash.Hash {
+	var s sum128a
+	s[0] = offset128Higher
+	s[1] = offset128Lower
+	return &s
+}
+
+func (s *sum32) Reset()   { *s = offset32 }
+func (s *sum32a) Reset()  { *s = offset32 }
+func (s *sum64) Reset()   { *s = offset64 }
+func (s *sum64a) Reset()  { *s = offset64 }
+func (s *sum128) Reset()  { s[0] = offset128Higher; s[1] = offset128Lower }
+func (s *sum128a) Reset() { s[0] = offset128Higher; s[1] = offset128Lower }
 
 func (s *sum32) Sum32() uint32  { return uint32(*s) }
 func (s *sum32a) Sum32() uint32 { return uint32(*s) }
@@ -104,15 +130,57 @@
 	return len(data), nil
 }
 
-func (s *sum32) Size() int  { return 4 }
-func (s *sum32a) Size() int { return 4 }
-func (s *sum64) Size() int  { return 8 }
-func (s *sum64a) Size() int { return 8 }
+func (s *sum128) Write(data []byte) (int, error) {
+	for _, c := range data {
+		// Compute the multiplication in 4 parts to simplify carrying
+		s1l := (s[1] & 0xffffffff) * prime128Lower
+		s1h := (s[1] >> 32) * prime128Lower
+		s0l := (s[0]&0xffffffff)*prime128Lower + (s[1]&0xffffffff)<<prime128Shift
+		s0h := (s[0]>>32)*prime128Lower + (s[1]>>32)<<prime128Shift
+		// Carries
+		s1h += s1l >> 32
+		s0l += s1h >> 32
+		s0h += s0l >> 32
+		// Update the values
+		s[1] = (s1l & 0xffffffff) + (s1h << 32)
+		s[0] = (s0l & 0xffffffff) + (s0h << 32)
+		s[1] ^= uint64(c)
+	}
+	return len(data), nil
+}
 
-func (s *sum32) BlockSize() int  { return 1 }
-func (s *sum32a) BlockSize() int { return 1 }
-func (s *sum64) BlockSize() int  { return 1 }
-func (s *sum64a) BlockSize() int { return 1 }
+func (s *sum128a) Write(data []byte) (int, error) {
+	for _, c := range data {
+		s[1] ^= uint64(c)
+		// Compute the multiplication in 4 parts to simplify carrying
+		s1l := (s[1] & 0xffffffff) * prime128Lower
+		s1h := (s[1] >> 32) * prime128Lower
+		s0l := (s[0]&0xffffffff)*prime128Lower + (s[1]&0xffffffff)<<prime128Shift
+		s0h := (s[0]>>32)*prime128Lower + (s[1]>>32)<<prime128Shift
+		// Carries
+		s1h += s1l >> 32
+		s0l += s1h >> 32
+		s0h += s0l >> 32
+		// Update the values
+		s[1] = (s1l & 0xffffffff) + (s1h << 32)
+		s[0] = (s0l & 0xffffffff) + (s0h << 32)
+	}
+	return len(data), nil
+}
+
+func (s *sum32) Size() int   { return 4 }
+func (s *sum32a) Size() int  { return 4 }
+func (s *sum64) Size() int   { return 8 }
+func (s *sum64a) Size() int  { return 8 }
+func (s *sum128) Size() int  { return 16 }
+func (s *sum128a) Size() int { return 16 }
+
+func (s *sum32) BlockSize() int   { return 1 }
+func (s *sum32a) BlockSize() int  { return 1 }
+func (s *sum64) BlockSize() int   { return 1 }
+func (s *sum64a) BlockSize() int  { return 1 }
+func (s *sum128) BlockSize() int  { return 1 }
+func (s *sum128a) BlockSize() int { return 1 }
 
 func (s *sum32) Sum(in []byte) []byte {
 	v := uint32(*s)
@@ -133,3 +201,17 @@
 	v := uint64(*s)
 	return append(in, byte(v>>56), byte(v>>48), byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
 }
+
+func (s *sum128) Sum(in []byte) []byte {
+	return append(in,
+		byte(s[0]>>56), byte(s[0]>>48), byte(s[0]>>40), byte(s[0]>>32), byte(s[0]>>24), byte(s[0]>>16), byte(s[0]>>8), byte(s[0]),
+		byte(s[1]>>56), byte(s[1]>>48), byte(s[1]>>40), byte(s[1]>>32), byte(s[1]>>24), byte(s[1]>>16), byte(s[1]>>8), byte(s[1]),
+	)
+}
+
+func (s *sum128a) Sum(in []byte) []byte {
+	return append(in,
+		byte(s[0]>>56), byte(s[0]>>48), byte(s[0]>>40), byte(s[0]>>32), byte(s[0]>>24), byte(s[0]>>16), byte(s[0]>>8), byte(s[0]),
+		byte(s[1]>>56), byte(s[1]>>48), byte(s[1]>>40), byte(s[1]>>32), byte(s[1]>>24), byte(s[1]>>16), byte(s[1]>>8), byte(s[1]),
+	)
+}
diff --git a/libgo/go/hash/fnv/fnv_test.go b/libgo/go/hash/fnv/fnv_test.go
index 89d39b3..7da15ba 100644
--- a/libgo/go/hash/fnv/fnv_test.go
+++ b/libgo/go/hash/fnv/fnv_test.go
@@ -44,6 +44,20 @@
 	{[]byte{0xe7, 0x1f, 0xa2, 0x19, 0x05, 0x41, 0x57, 0x4b}, "abc"},
 }
 
+var golden128 = []golden{
+	{[]byte{0x6c, 0x62, 0x27, 0x2e, 0x07, 0xbb, 0x01, 0x42, 0x62, 0xb8, 0x21, 0x75, 0x62, 0x95, 0xc5, 0x8d}, ""},
+	{[]byte{0xd2, 0x28, 0xcb, 0x69, 0x10, 0x1a, 0x8c, 0xaf, 0x78, 0x91, 0x2b, 0x70, 0x4e, 0x4a, 0x14, 0x1e}, "a"},
+	{[]byte{0x8, 0x80, 0x94, 0x5a, 0xee, 0xab, 0x1b, 0xe9, 0x5a, 0xa0, 0x73, 0x30, 0x55, 0x26, 0xc0, 0x88}, "ab"},
+	{[]byte{0xa6, 0x8b, 0xb2, 0xa4, 0x34, 0x8b, 0x58, 0x22, 0x83, 0x6d, 0xbc, 0x78, 0xc6, 0xae, 0xe7, 0x3b}, "abc"},
+}
+
+var golden128a = []golden{
+	{[]byte{0x6c, 0x62, 0x27, 0x2e, 0x07, 0xbb, 0x01, 0x42, 0x62, 0xb8, 0x21, 0x75, 0x62, 0x95, 0xc5, 0x8d}, ""},
+	{[]byte{0xd2, 0x28, 0xcb, 0x69, 0x6f, 0x1a, 0x8c, 0xaf, 0x78, 0x91, 0x2b, 0x70, 0x4e, 0x4a, 0x89, 0x64}, "a"},
+	{[]byte{0x08, 0x80, 0x95, 0x44, 0xbb, 0xab, 0x1b, 0xe9, 0x5a, 0xa0, 0x73, 0x30, 0x55, 0xb6, 0x9a, 0x62}, "ab"},
+	{[]byte{0xa6, 0x8d, 0x62, 0x2c, 0xec, 0x8b, 0x58, 0x22, 0x83, 0x6d, 0xbc, 0x79, 0x77, 0xaf, 0x7f, 0x3b}, "abc"},
+}
+
 func TestGolden32(t *testing.T) {
 	testGolden(t, New32(), golden32)
 }
@@ -60,6 +74,14 @@
 	testGolden(t, New64a(), golden64a)
 }
 
+func TestGolden128(t *testing.T) {
+	testGolden(t, New128(), golden128)
+}
+
+func TestGolden128a(t *testing.T) {
+	testGolden(t, New128a(), golden128a)
+}
+
 func testGolden(t *testing.T, hash hash.Hash, gold []golden) {
 	for _, g := range gold {
 		hash.Reset()
@@ -91,6 +113,13 @@
 func TestIntegrity64a(t *testing.T) {
 	testIntegrity(t, New64a())
 }
+func TestIntegrity128(t *testing.T) {
+	testIntegrity(t, New128())
+}
+
+func TestIntegrity128a(t *testing.T) {
+	testIntegrity(t, New128a())
+}
 
 func testIntegrity(t *testing.T, h hash.Hash) {
 	data := []byte{'1', '2', 3, 4, 5}
@@ -129,6 +158,8 @@
 		if sum64 != binary.BigEndian.Uint64(sum) {
 			t.Fatalf("Sum()=0x%x, but Sum64()=0x%x", sum, sum64)
 		}
+	case 16:
+		// There's no Sum128 function, so we don't need to test anything here.
 	}
 }
 
@@ -148,6 +179,14 @@
 	benchmarkKB(b, New64a())
 }
 
+func BenchmarkFnv128KB(b *testing.B) {
+	benchmarkKB(b, New128())
+}
+
+func BenchmarkFnv128aKB(b *testing.B) {
+	benchmarkKB(b, New128a())
+}
+
 func benchmarkKB(b *testing.B, h hash.Hash) {
 	b.SetBytes(1024)
 	data := make([]byte, 1024)
diff --git a/libgo/go/html/template/attr.go b/libgo/go/html/template/attr.go
index d65d340..7438f51 100644
--- a/libgo/go/html/template/attr.go
+++ b/libgo/go/html/template/attr.go
@@ -135,9 +135,8 @@
 }
 
 // attrType returns a conservative (upper-bound on authority) guess at the
-// type of the named attribute.
+// type of the lowercase named attribute.
 func attrType(name string) contentType {
-	name = strings.ToLower(name)
 	if strings.HasPrefix(name, "data-") {
 		// Strip data- so that custom attribute heuristics below are
 		// widely applied.
diff --git a/libgo/go/html/template/doc.go b/libgo/go/html/template/doc.go
index cb89812..35d171c 100644
--- a/libgo/go/html/template/doc.go
+++ b/libgo/go/html/template/doc.go
@@ -65,8 +65,10 @@
 At parse time each {{.}} is overwritten to add escaping functions as necessary.
 In this case it becomes
 
-  <a href="/search?q={{. | urlquery}}">{{. | html}}</a>
+  <a href="/search?q={{. | urlescaper | attrescaper}}">{{. | htmlescaper}}</a>
 
+where urlescaper, attrescaper, and htmlescaper are aliases for internal escaping
+functions.
 
 Errors
 
diff --git a/libgo/go/html/template/error.go b/libgo/go/html/template/error.go
index cbcaf92..0e52706 100644
--- a/libgo/go/html/template/error.go
+++ b/libgo/go/html/template/error.go
@@ -183,6 +183,34 @@
 	//   Look for missing semicolons inside branches, and maybe add
 	//   parentheses to make it clear which interpretation you intend.
 	ErrSlashAmbig
+
+	// ErrPredefinedEscaper: "predefined escaper ... disallowed in template"
+	// Example:
+	//   <div class={{. | html}}>Hello<div>
+	// Discussion:
+	//   Package html/template already contextually escapes all pipelines to
+	//   produce HTML output safe against code injection. Manually escaping
+	//   pipeline output using the predefined escapers "html" or "urlquery" is
+	//   unnecessary, and may affect the correctness or safety of the escaped
+	//   pipeline output in Go 1.8 and earlier.
+	//
+	//   In most cases, such as the given example, this error can be resolved by
+	//   simply removing the predefined escaper from the pipeline and letting the
+	//   contextual autoescaper handle the escaping of the pipeline. In other
+	//   instances, where the predefined escaper occurs in the middle of a
+	//   pipeline where subsequent commands expect escaped input, e.g.
+	//     {{.X | html | makeALink}}
+	//   where makeALink does
+	//     return `<a href="`+input+`">link</a>`
+	//   consider refactoring the surrounding template to make use of the
+	//   contextual autoescaper, i.e.
+	//     <a href="{{.X}}">link</a>
+	//
+	//   To ease migration to Go 1.9 and beyond, "html" and "urlquery" will
+	//   continue to be allowed as the last command in a pipeline. However, if the
+	//   pipeline occurs in an unquoted attribute value context, "html" is
+	//   disallowed. Avoid using "html" and "urlquery" entirely in new templates.
+	ErrPredefinedEscaper
 )
 
 func (e *Error) Error() string {
diff --git a/libgo/go/html/template/escape.go b/libgo/go/html/template/escape.go
index 0e7d2be..b51a370 100644
--- a/libgo/go/html/template/escape.go
+++ b/libgo/go/html/template/escape.go
@@ -19,8 +19,7 @@
 // been modified. Otherwise the named templates have been rendered
 // unusable.
 func escapeTemplate(tmpl *Template, node parse.Node, name string) error {
-	e := newEscaper(tmpl)
-	c, _ := e.escapeTree(context{}, node, name, 0)
+	c, _ := tmpl.esc.escapeTree(context{}, node, name, 0)
 	var err error
 	if c.err != nil {
 		err, c.err.Name = c.err, name
@@ -36,7 +35,7 @@
 		}
 		return err
 	}
-	e.commit()
+	tmpl.esc.commit()
 	if t := tmpl.set[name]; t != nil {
 		t.escapeErr = escapeOK
 		t.Tree = t.text.Tree
@@ -44,6 +43,21 @@
 	return nil
 }
 
+// evalArgs formats the list of arguments into a string. It is equivalent to
+// fmt.Sprint(args...), except that it deferences all pointers.
+func evalArgs(args ...interface{}) string {
+	// Optimization for simple common case of a single string argument.
+	if len(args) == 1 {
+		if s, ok := args[0].(string); ok {
+			return s
+		}
+	}
+	for i, arg := range args {
+		args[i] = indirectToStringerOrError(arg)
+	}
+	return fmt.Sprint(args...)
+}
+
 // funcMap maps command names to functions that render their inputs safe.
 var funcMap = template.FuncMap{
 	"_html_template_attrescaper":     attrEscaper,
@@ -60,22 +74,14 @@
 	"_html_template_urlescaper":      urlEscaper,
 	"_html_template_urlfilter":       urlFilter,
 	"_html_template_urlnormalizer":   urlNormalizer,
-}
-
-// equivEscapers matches contextual escapers to equivalent template builtins.
-var equivEscapers = map[string]string{
-	"_html_template_attrescaper":    "html",
-	"_html_template_htmlescaper":    "html",
-	"_html_template_nospaceescaper": "html",
-	"_html_template_rcdataescaper":  "html",
-	"_html_template_urlescaper":     "urlquery",
-	"_html_template_urlnormalizer":  "urlquery",
+	"_eval_args_":                    evalArgs,
 }
 
 // escaper collects type inferences about templates and changes needed to make
 // templates injection safe.
 type escaper struct {
-	tmpl *Template
+	// ns is the nameSpace that this escaper is associated with.
+	ns *nameSpace
 	// output[templateName] is the output context for a templateName that
 	// has been mangled to include its input context.
 	output map[string]context
@@ -92,10 +98,10 @@
 	textNodeEdits     map[*parse.TextNode][]byte
 }
 
-// newEscaper creates a blank escaper for the given set.
-func newEscaper(t *Template) *escaper {
-	return &escaper{
-		t,
+// makeEscaper creates a blank escaper for the given set.
+func makeEscaper(n *nameSpace) escaper {
+	return escaper{
+		n,
 		map[string]context{},
 		map[string]*template.Template{},
 		map[string]bool{},
@@ -140,6 +146,30 @@
 		return c
 	}
 	c = nudge(c)
+	// Check for disallowed use of predefined escapers in the pipeline.
+	for pos, idNode := range n.Pipe.Cmds {
+		node, ok := idNode.Args[0].(*parse.IdentifierNode)
+		if !ok {
+			// A predefined escaper "esc" will never be found as an identifier in a
+			// Chain or Field node, since:
+			// - "esc.x ..." is invalid, since predefined escapers return strings, and
+			//   strings do not have methods, keys or fields.
+			// - "... .esc" is invalid, since predefined escapers are global functions,
+			//   not methods or fields of any types.
+			// Therefore, it is safe to ignore these two node types.
+			continue
+		}
+		ident := node.Ident
+		if _, ok := predefinedEscapers[ident]; ok {
+			if pos < len(n.Pipe.Cmds)-1 ||
+				c.state == stateAttr && c.delim == delimSpaceOrTagEnd && ident == "html" {
+				return context{
+					state: stateError,
+					err:   errorf(ErrPredefinedEscaper, n, n.Line, "predefined escaper %q disallowed in template", ident),
+				}
+			}
+		}
+	}
 	s := make([]string, 0, 3)
 	switch c.state {
 	case stateError:
@@ -204,75 +234,98 @@
 	return c
 }
 
-// allIdents returns the names of the identifiers under the Ident field of the node,
-// which might be a singleton (Identifier) or a slice (Field or Chain).
-func allIdents(node parse.Node) []string {
-	switch node := node.(type) {
-	case *parse.IdentifierNode:
-		return []string{node.Ident}
-	case *parse.FieldNode:
-		return node.Ident
-	case *parse.ChainNode:
-		return node.Field
-	}
-	return nil
-}
-
-// ensurePipelineContains ensures that the pipeline has commands with
-// the identifiers in s in order.
-// If the pipeline already has some of the sanitizers, do not interfere.
-// For example, if p is (.X | html) and s is ["escapeJSVal", "html"] then it
-// has one matching, "html", and one to insert, "escapeJSVal", to produce
-// (.X | escapeJSVal | html).
+// ensurePipelineContains ensures that the pipeline ends with the commands with
+// the identifiers in s in order. If the pipeline ends with a predefined escaper
+// (i.e. "html" or "urlquery"), merge it with the identifiers in s.
 func ensurePipelineContains(p *parse.PipeNode, s []string) {
 	if len(s) == 0 {
+		// Do not rewrite pipeline if we have no escapers to insert.
 		return
 	}
-	n := len(p.Cmds)
-	// Find the identifiers at the end of the command chain.
-	idents := p.Cmds
-	for i := n - 1; i >= 0; i-- {
-		if cmd := p.Cmds[i]; len(cmd.Args) != 0 {
-			if _, ok := cmd.Args[0].(*parse.IdentifierNode); ok {
-				continue
-			}
-		}
-		idents = p.Cmds[i+1:]
-	}
-	dups := 0
-	for _, idNode := range idents {
-		for _, ident := range allIdents(idNode.Args[0]) {
-			if escFnsEq(s[dups], ident) {
-				dups++
-				if dups == len(s) {
-					return
+	// Precondition: p.Cmds contains at most one predefined escaper and the
+	// escaper will be present at p.Cmds[len(p.Cmds)-1]. This precondition is
+	// always true because of the checks in escapeAction.
+	pipelineLen := len(p.Cmds)
+	if pipelineLen > 0 {
+		lastCmd := p.Cmds[pipelineLen-1]
+		if idNode, ok := lastCmd.Args[0].(*parse.IdentifierNode); ok {
+			if esc := idNode.Ident; predefinedEscapers[esc] {
+				// Pipeline ends with a predefined escaper.
+				if len(p.Cmds) == 1 && len(lastCmd.Args) > 1 {
+					// Special case: pipeline is of the form {{ esc arg1 arg2 ... argN }},
+					// where esc is the predefined escaper, and arg1...argN are its arguments.
+					// Convert this into the equivalent form
+					// {{ _eval_args_ arg1 arg2 ... argN | esc }}, so that esc can be easily
+					// merged with the escapers in s.
+					lastCmd.Args[0] = parse.NewIdentifier("_eval_args_").SetTree(nil).SetPos(lastCmd.Args[0].Position())
+					p.Cmds = appendCmd(p.Cmds, newIdentCmd(esc, p.Position()))
+					pipelineLen++
+				}
+				// If any of the commands in s that we are about to insert is equivalent
+				// to the predefined escaper, use the predefined escaper instead.
+				dup := false
+				for i, escaper := range s {
+					if escFnsEq(esc, escaper) {
+						s[i] = idNode.Ident
+						dup = true
+					}
+				}
+				if dup {
+					// The predefined escaper will already be inserted along with the
+					// escapers in s, so do not copy it to the rewritten pipeline.
+					pipelineLen--
 				}
 			}
 		}
 	}
-	newCmds := make([]*parse.CommandNode, n-len(idents), n+len(s)-dups)
+	// Rewrite the pipeline, creating the escapers in s at the end of the pipeline.
+	newCmds := make([]*parse.CommandNode, pipelineLen, pipelineLen+len(s))
 	copy(newCmds, p.Cmds)
-	// Merge existing identifier commands with the sanitizers needed.
-	for _, idNode := range idents {
-		pos := idNode.Args[0].Position()
-		for _, ident := range allIdents(idNode.Args[0]) {
-			i := indexOfStr(ident, s, escFnsEq)
-			if i != -1 {
-				for _, name := range s[:i] {
-					newCmds = appendCmd(newCmds, newIdentCmd(name, pos))
-				}
-				s = s[i+1:]
-			}
-		}
-		newCmds = appendCmd(newCmds, idNode)
-	}
-	// Create any remaining sanitizers.
 	for _, name := range s {
 		newCmds = appendCmd(newCmds, newIdentCmd(name, p.Position()))
 	}
 	p.Cmds = newCmds
 }
 
+// predefinedEscapers contains template predefined escapers that are equivalent
+// to some contextual escapers. Keep in sync with equivEscapers.
+var predefinedEscapers = map[string]bool{
+	"html":     true,
+	"urlquery": true,
+}
+
+// equivEscapers matches contextual escapers to equivalent predefined
+// template escapers.
+var equivEscapers = map[string]string{
+	// The following pairs of HTML escapers provide equivalent security
+	// guarantees, since they all escape '\000', '\'', '"', '&', '<', and '>'.
+	"_html_template_attrescaper":   "html",
+	"_html_template_htmlescaper":   "html",
+	"_html_template_rcdataescaper": "html",
+	// These two URL escapers produce URLs safe for embedding in a URL query by
+	// percent-encoding all the reserved characters specified in RFC 3986 Section
+	// 2.2
+	"_html_template_urlescaper": "urlquery",
+	// These two functions are not actually equivalent; urlquery is stricter as it
+	// escapes reserved characters (e.g. '#'), while _html_template_urlnormalizer
+	// does not. It is therefore only safe to replace _html_template_urlnormalizer
+	// with urlquery (this happens in ensurePipelineContains), but not the otherI've
+	// way around. We keep this entry around to preserve the behavior of templates
+	// written before Go 1.9, which might depend on this substitution taking place.
+	"_html_template_urlnormalizer": "urlquery",
+}
+
+// escFnsEq reports whether the two escaping functions are equivalent.
+func escFnsEq(a, b string) bool {
+	if e := equivEscapers[a]; e != "" {
+		a = e
+	}
+	if e := equivEscapers[b]; e != "" {
+		b = e
+	}
+	return a == b
+}
+
 // redundantFuncs[a][b] implies that funcMap[b](funcMap[a](x)) == funcMap[a](x)
 // for all x.
 var redundantFuncs = map[string]map[string]bool{
@@ -318,17 +371,6 @@
 	return -1
 }
 
-// escFnsEq reports whether the two escaping functions are equivalent.
-func escFnsEq(a, b string) bool {
-	if e := equivEscapers[a]; e != "" {
-		a = e
-	}
-	if e := equivEscapers[b]; e != "" {
-		b = e
-	}
-	return a == b
-}
-
 // newIdentCmd produces a command containing a single identifier node.
 func newIdentCmd(identifier string, pos parse.Pos) *parse.CommandNode {
 	return &parse.CommandNode{
@@ -449,13 +491,13 @@
 // It returns the best guess at an output context, and the result of the filter
 // which is the same as whether e was updated.
 func (e *escaper) escapeListConditionally(c context, n *parse.ListNode, filter func(*escaper, context) bool) (context, bool) {
-	e1 := newEscaper(e.tmpl)
+	e1 := makeEscaper(e.ns)
 	// Make type inferences available to f.
 	for k, v := range e.output {
 		e1.output[k] = v
 	}
 	c = e1.escapeList(c, n)
-	ok := filter != nil && filter(e1, c)
+	ok := filter != nil && filter(&e1, c)
 	if ok {
 		// Copy inferences and edits from e1 back into e.
 		for k, v := range e1.output {
@@ -504,7 +546,7 @@
 	if t == nil {
 		// Two cases: The template exists but is empty, or has never been mentioned at
 		// all. Distinguish the cases in the error messages.
-		if e.tmpl.set[name] != nil {
+		if e.ns.set[name] != nil {
 			return context{
 				state: stateError,
 				err:   errorf(ErrNoSuchTemplate, node, line, "%q is an incomplete or empty template", name),
@@ -624,7 +666,7 @@
 				// the entire comment is considered to be a
 				// LineTerminator for purposes of parsing by
 				// the syntactic grammar."
-				if bytes.IndexAny(s[written:i1], "\n\r\u2028\u2029") != -1 {
+				if bytes.ContainsAny(s[written:i1], "\n\r\u2028\u2029") {
 					b.WriteByte('\n')
 				} else {
 					b.WriteByte(' ')
@@ -752,8 +794,11 @@
 	for name := range e.output {
 		e.template(name).Funcs(funcMap)
 	}
+	// Any template from the name space associated with this escaper can be used
+	// to add derived templates to the underlying text/template name space.
+	tmpl := e.arbitraryTemplate()
 	for _, t := range e.derived {
-		if _, err := e.tmpl.text.AddParseTree(t.Name(), t.Tree); err != nil {
+		if _, err := tmpl.text.AddParseTree(t.Name(), t.Tree); err != nil {
 			panic("error adding derived template")
 		}
 	}
@@ -766,17 +811,34 @@
 	for n, s := range e.textNodeEdits {
 		n.Text = s
 	}
+	// Reset state that is specific to this commit so that the same changes are
+	// not re-applied to the template on subsequent calls to commit.
+	e.called = make(map[string]bool)
+	e.actionNodeEdits = make(map[*parse.ActionNode][]string)
+	e.templateNodeEdits = make(map[*parse.TemplateNode]string)
+	e.textNodeEdits = make(map[*parse.TextNode][]byte)
 }
 
 // template returns the named template given a mangled template name.
 func (e *escaper) template(name string) *template.Template {
-	t := e.tmpl.text.Lookup(name)
+	// Any template from the name space associated with this escaper can be used
+	// to look up templates in the underlying text/template name space.
+	t := e.arbitraryTemplate().text.Lookup(name)
 	if t == nil {
 		t = e.derived[name]
 	}
 	return t
 }
 
+// arbitraryTemplate returns an arbitrary template from the name space
+// associated with e and panics if no templates are found.
+func (e *escaper) arbitraryTemplate() *Template {
+	for _, t := range e.ns.set {
+		return t
+	}
+	panic("no templates in name space")
+}
+
 // Forwarding functions so that clients need only import this package
 // to reach the general escaping functions of text/template.
 
diff --git a/libgo/go/html/template/escape_test.go b/libgo/go/html/template/escape_test.go
index f6ace49..f5a4ce1 100644
--- a/libgo/go/html/template/escape_test.go
+++ b/libgo/go/html/template/escape_test.go
@@ -359,7 +359,7 @@
 		{
 			"styleStrEncodedProtocolEncoded",
 			`<a style="background: '{{"javascript\\3a alert(1337)"}}'">`,
-			// The CSS string 'javascript\\3a alert(1337)' does not contains a colon.
+			// The CSS string 'javascript\\3a alert(1337)' does not contain a colon.
 			`<a style="background: 'javascript\\3a alert\28 1337\29 '">`,
 		},
 		{
@@ -685,6 +685,40 @@
 	}
 }
 
+func TestEscapeMap(t *testing.T) {
+	data := map[string]string{
+		"html":     `<h1>Hi!</h1>`,
+		"urlquery": `http://www.foo.com/index.html?title=main`,
+	}
+	for _, test := range [...]struct {
+		desc, input, output string
+	}{
+		// covering issue 20323
+		{
+			"field with predefined escaper name 1",
+			`{{.html | print}}`,
+			`&lt;h1&gt;Hi!&lt;/h1&gt;`,
+		},
+		// covering issue 20323
+		{
+			"field with predefined escaper name 2",
+			`{{.urlquery | print}}`,
+			`http://www.foo.com/index.html?title=main`,
+		},
+	} {
+		tmpl := Must(New("").Parse(test.input))
+		b := new(bytes.Buffer)
+		if err := tmpl.Execute(b, data); err != nil {
+			t.Errorf("%s: template execution failed: %s", test.desc, err)
+			continue
+		}
+		if w, g := test.output, b.String(); w != g {
+			t.Errorf("%s: escaped output: want\n\t%q\ngot\n\t%q", test.desc, w, g)
+			continue
+		}
+	}
+}
+
 func TestEscapeSet(t *testing.T) {
 	type dataItem struct {
 		Children []*dataItem
@@ -970,8 +1004,33 @@
 			`<a=foo>`,
 			`: expected space, attr name, or end of tag, but got "=foo>"`,
 		},
+		{
+			`Hello, {{. | urlquery | print}}!`,
+			// urlquery is disallowed if it is not the last command in the pipeline.
+			`predefined escaper "urlquery" disallowed in template`,
+		},
+		{
+			`Hello, {{. | html | print}}!`,
+			// html is disallowed if it is not the last command in the pipeline.
+			`predefined escaper "html" disallowed in template`,
+		},
+		{
+			`Hello, {{html . | print}}!`,
+			// A direct call to html is disallowed if it is not the last command in the pipeline.
+			`predefined escaper "html" disallowed in template`,
+		},
+		{
+			`<div class={{. | html}}>Hello<div>`,
+			// html is disallowed in a pipeline that is in an unquoted attribute context,
+			// even if it is the last command in the pipeline.
+			`predefined escaper "html" disallowed in template`,
+		},
+		{
+			`Hello, {{. | urlquery | html}}!`,
+			// html is allowed since it is the last command in the pipeline, but urlquery is not.
+			`predefined escaper "urlquery" disallowed in template`,
+		},
 	}
-
 	for _, test := range tests {
 		buf := new(bytes.Buffer)
 		tmpl, err := New("z").Parse(test.input)
@@ -1396,6 +1455,16 @@
 			`<script type="text/template">`,
 			context{state: stateText},
 		},
+		// covering issue 19968
+		{
+			`<script type="TEXT/JAVASCRIPT">`,
+			context{state: stateJS, element: elementScript},
+		},
+		// covering issue 19965
+		{
+			`<script TYPE="text/template">`,
+			context{state: stateText},
+		},
 		{
 			`<script type="notjs">`,
 			context{state: stateText},
@@ -1495,7 +1564,7 @@
 	}
 
 	for _, test := range tests {
-		b, e := []byte(test.input), newEscaper(nil)
+		b, e := []byte(test.input), makeEscaper(nil)
 		c := e.escapeText(context{}, &parse.TextNode{NodeType: parse.NodeText, Text: b})
 		if !test.output.eq(c) {
 			t.Errorf("input %q: want context\n\t%v\ngot\n\t%v", test.input, test.output, c)
@@ -1529,24 +1598,24 @@
 			[]string{"html"},
 		},
 		{
-			"{{.X | html}}",
-			".X | html | urlquery",
-			[]string{"urlquery"},
-		},
-		{
-			"{{.X | html | urlquery}}",
-			".X | html | urlquery",
-			[]string{"urlquery"},
-		},
-		{
-			"{{.X | html | urlquery}}",
-			".X | html | urlquery",
+			"{{html .X}}",
+			"_eval_args_ .X | html | urlquery",
 			[]string{"html", "urlquery"},
 		},
 		{
-			"{{.X | html | urlquery}}",
-			".X | html | urlquery",
-			[]string{"html"},
+			"{{html .X .Y .Z}}",
+			"_eval_args_ .X .Y .Z | html | urlquery",
+			[]string{"html", "urlquery"},
+		},
+		{
+			"{{.X | print}}",
+			".X | print | urlquery",
+			[]string{"urlquery"},
+		},
+		{
+			"{{.X | print | urlquery}}",
+			".X | print | urlquery",
+			[]string{"urlquery"},
 		},
 		{
 			"{{.X | urlquery}}",
@@ -1554,50 +1623,69 @@
 			[]string{"html", "urlquery"},
 		},
 		{
-			"{{.X | html | print}}",
-			".X | urlquery | html | print",
-			[]string{"urlquery", "html"},
-		},
-		{
-			"{{($).X | html | print}}",
-			"($).X | urlquery | html | print",
-			[]string{"urlquery", "html"},
-		},
-		{
 			"{{.X | print 2 | .f 3}}",
 			".X | print 2 | .f 3 | urlquery | html",
 			[]string{"urlquery", "html"},
 		},
 		{
-			"{{.X | html | print 2 | .f 3}}",
-			".X | urlquery | html | print 2 | .f 3",
+			// covering issue 10801
+			"{{.X | println.x }}",
+			".X | println.x | urlquery | html",
 			[]string{"urlquery", "html"},
 		},
 		{
 			// covering issue 10801
-			"{{.X | js.x }}",
-			".X | js.x | urlquery | html",
+			"{{.X | (print 12 | println).x }}",
+			".X | (print 12 | println).x | urlquery | html",
 			[]string{"urlquery", "html"},
 		},
+		// The following test cases ensure that the merging of internal escapers
+		// with the predefined "html" and "urlquery" escapers is correct.
 		{
-			// covering issue 10801
-			"{{.X | (print 12 | js).x }}",
-			".X | (print 12 | js).x | urlquery | html",
-			[]string{"urlquery", "html"},
+			"{{.X | urlquery}}",
+			".X | _html_template_urlfilter | urlquery",
+			[]string{"_html_template_urlfilter", "_html_template_urlnormalizer"},
+		},
+		{
+			"{{.X | urlquery}}",
+			".X | urlquery | _html_template_urlfilter | _html_template_cssescaper",
+			[]string{"_html_template_urlfilter", "_html_template_cssescaper"},
+		},
+		{
+			"{{.X | urlquery}}",
+			".X | urlquery",
+			[]string{"_html_template_urlnormalizer"},
+		},
+		{
+			"{{.X | urlquery}}",
+			".X | urlquery",
+			[]string{"_html_template_urlescaper"},
+		},
+		{
+			"{{.X | html}}",
+			".X | html",
+			[]string{"_html_template_htmlescaper"},
+		},
+		{
+			"{{.X | html}}",
+			".X | html",
+			[]string{"_html_template_rcdataescaper"},
 		},
 	}
 	for i, test := range tests {
 		tmpl := template.Must(template.New("test").Parse(test.input))
 		action, ok := (tmpl.Tree.Root.Nodes[0].(*parse.ActionNode))
 		if !ok {
-			t.Errorf("#%d: First node is not an action: %s", i, test.input)
+			t.Errorf("First node is not an action: %s", test.input)
 			continue
 		}
 		pipe := action.Pipe
+		originalIDs := make([]string, len(test.ids))
+		copy(originalIDs, test.ids)
 		ensurePipelineContains(pipe, test.ids)
 		got := pipe.String()
 		if got != test.output {
-			t.Errorf("#%d: %s, %v: want\n\t%s\ngot\n\t%s", i, test.input, test.ids, test.output, got)
+			t.Errorf("#%d: %s, %v: want\n\t%s\ngot\n\t%s", i, test.input, originalIDs, test.output, got)
 		}
 	}
 }
@@ -1606,10 +1694,8 @@
 	tests := []string{
 		"{{ 0 | $ }}",
 		"{{ 0 | $ | urlquery }}",
-		"{{ 0 | $ | urlquery | html }}",
 		"{{ 0 | (nil) }}",
 		"{{ 0 | (nil) | html }}",
-		"{{ 0 | (nil) | html | urlquery }}",
 	}
 	for _, test := range tests {
 		var b bytes.Buffer
@@ -1761,6 +1847,40 @@
 	}
 }
 
+// This covers issue #20842.
+func TestIdempotentExecute(t *testing.T) {
+	tmpl := Must(New("").
+		Parse(`{{define "main"}}<body>{{template "hello"}}</body>{{end}}`))
+	Must(tmpl.
+		Parse(`{{define "hello"}}Hello, {{"Ladies & Gentlemen!"}}{{end}}`))
+	got := new(bytes.Buffer)
+	var err error
+	// Ensure that "hello" produces the same output when executed twice.
+	want := "Hello, Ladies &amp; Gentlemen!"
+	for i := 0; i < 2; i++ {
+		err = tmpl.ExecuteTemplate(got, "hello", nil)
+		if err != nil {
+			t.Errorf("unexpected error: %s", err)
+		}
+		if got.String() != want {
+			t.Errorf("after executing template \"hello\", got:\n\t%q\nwant:\n\t%q\n", got.String(), want)
+		}
+		got.Reset()
+	}
+	// Ensure that the implicit re-execution of "hello" during the execution of
+	// "main" does not cause the output of "hello" to change.
+	err = tmpl.ExecuteTemplate(got, "main", nil)
+	if err != nil {
+		t.Errorf("unexpected error: %s", err)
+	}
+	// If the HTML escaper is added again to the action {{"Ladies & Gentlemen!"}},
+	// we would expected to see the ampersand overescaped to "&amp;amp;".
+	want = "<body>Hello, Ladies &amp; Gentlemen!</body>"
+	if got.String() != want {
+		t.Errorf("after executing template \"main\", got:\n\t%q\nwant:\n\t%q\n", got.String(), want)
+	}
+}
+
 func BenchmarkEscapedExecute(b *testing.B) {
 	tmpl := Must(New("t").Parse(`<a onclick="alert('{{.}}')">{{.}}</a>`))
 	var buf bytes.Buffer
diff --git a/libgo/go/html/template/js.go b/libgo/go/html/template/js.go
index 6434fa3..239395f 100644
--- a/libgo/go/html/template/js.go
+++ b/libgo/go/html/template/js.go
@@ -372,7 +372,7 @@
 	//   https://tools.ietf.org/html/rfc7231#section-3.1.1
 	//   https://tools.ietf.org/html/rfc4329#section-3
 	//   https://www.ietf.org/rfc/rfc4627.txt
-
+	mimeType = strings.ToLower(mimeType)
 	// discard parameters
 	if i := strings.Index(mimeType, ";"); i >= 0 {
 		mimeType = mimeType[:i]
diff --git a/libgo/go/html/template/template.go b/libgo/go/html/template/template.go
index b313a6b..6a661bf 100644
--- a/libgo/go/html/template/template.go
+++ b/libgo/go/html/template/template.go
@@ -36,6 +36,7 @@
 	mu      sync.Mutex
 	set     map[string]*Template
 	escaped bool
+	esc     escaper
 }
 
 // Templates returns a slice of the templates associated with t, including t
@@ -112,7 +113,8 @@
 // If an error occurs executing the template or writing its output,
 // execution stops, but partial results may already have been written to
 // the output writer.
-// A template may be executed safely in parallel.
+// A template may be executed safely in parallel, although if parallel
+// executions share a Writer the output may be interleaved.
 func (t *Template) Execute(wr io.Writer, data interface{}) error {
 	if err := t.escape(); err != nil {
 		return err
@@ -125,7 +127,8 @@
 // If an error occurs executing the template or writing its output,
 // execution stops, but partial results may already have been written to
 // the output writer.
-// A template may be executed safely in parallel.
+// A template may be executed safely in parallel, although if parallel
+// executions share a Writer the output may be interleaved.
 func (t *Template) ExecuteTemplate(wr io.Writer, name string, data interface{}) error {
 	tmpl, err := t.lookupAndEscapeTemplate(name)
 	if err != nil {
@@ -248,13 +251,13 @@
 	if err != nil {
 		return nil, err
 	}
+	ns := &nameSpace{set: make(map[string]*Template)}
+	ns.esc = makeEscaper(ns)
 	ret := &Template{
 		nil,
 		textClone,
 		textClone.Tree,
-		&nameSpace{
-			set: make(map[string]*Template),
-		},
+		ns,
 	}
 	ret.set[ret.Name()] = ret
 	for _, x := range textClone.Templates() {
@@ -277,13 +280,13 @@
 
 // New allocates a new HTML template with the given name.
 func New(name string) *Template {
+	ns := &nameSpace{set: make(map[string]*Template)}
+	ns.esc = makeEscaper(ns)
 	tmpl := &Template{
 		nil,
 		template.New(name),
 		nil,
-		&nameSpace{
-			set: make(map[string]*Template),
-		},
+		ns,
 	}
 	tmpl.set[name] = tmpl
 	return tmpl
@@ -325,6 +328,7 @@
 type FuncMap map[string]interface{}
 
 // Funcs adds the elements of the argument map to the template's function map.
+// It must be called before the template is parsed.
 // It panics if a value in the map is not a function with appropriate return
 // type. However, it is legal to overwrite elements of the map. The return
 // value is the template, so calls can be chained.
diff --git a/libgo/go/html/template/transition.go b/libgo/go/html/template/transition.go
index 4a4716d..df7ac22 100644
--- a/libgo/go/html/template/transition.go
+++ b/libgo/go/html/template/transition.go
@@ -106,7 +106,7 @@
 		}, len(s)
 	}
 
-	attrName := string(s[i:j])
+	attrName := strings.ToLower(string(s[i:j]))
 	if c.element == elementScript && attrName == "type" {
 		attr = attrScriptType
 	} else {
@@ -246,7 +246,7 @@
 
 // tURL is the context transition function for the URL state.
 func tURL(c context, s []byte) (context, int) {
-	if bytes.IndexAny(s, "#?") >= 0 {
+	if bytes.ContainsAny(s, "#?") {
 		c.urlPart = urlPartQueryOrFrag
 	} else if len(s) != eatWhiteSpace(s, 0) && c.urlPart == urlPartNone {
 		// HTML5 uses "Valid URL potentially surrounded by spaces" for
diff --git a/libgo/go/image/color/ycbcr.go b/libgo/go/image/color/ycbcr.go
index 18d1a56..fd24430 100644
--- a/libgo/go/image/color/ycbcr.go
+++ b/libgo/go/image/color/ycbcr.go
@@ -61,8 +61,58 @@
 	//	G = Y' - 0.34414*(Cb-128) - 0.71414*(Cr-128)
 	//	B = Y' + 1.77200*(Cb-128)
 	// http://www.w3.org/Graphics/JPEG/jfif3.pdf says Y but means Y'.
-
-	yy1 := int32(y) * 0x010100 // Convert 0x12 to 0x121200.
+	//
+	// Those formulae use non-integer multiplication factors. When computing,
+	// integer math is generally faster than floating point math. We multiply
+	// all of those factors by 1<<16 and round to the nearest integer:
+	//	 91881 = roundToNearestInteger(1.40200 * 65536).
+	//	 22554 = roundToNearestInteger(0.34414 * 65536).
+	//	 46802 = roundToNearestInteger(0.71414 * 65536).
+	//	116130 = roundToNearestInteger(1.77200 * 65536).
+	//
+	// Adding a rounding adjustment in the range [0, 1<<16-1] and then shifting
+	// right by 16 gives us an integer math version of the original formulae.
+	//	R = (65536*Y' +  91881 *(Cr-128)                  + adjustment) >> 16
+	//	G = (65536*Y' -  22554 *(Cb-128) - 46802*(Cr-128) + adjustment) >> 16
+	//	B = (65536*Y' + 116130 *(Cb-128)                  + adjustment) >> 16
+	// A constant rounding adjustment of 1<<15, one half of 1<<16, would mean
+	// round-to-nearest when dividing by 65536 (shifting right by 16).
+	// Similarly, a constant rounding adjustment of 0 would mean round-down.
+	//
+	// Defining YY1 = 65536*Y' + adjustment simplifies the formulae and
+	// requires fewer CPU operations:
+	//	R = (YY1 +  91881 *(Cr-128)                 ) >> 16
+	//	G = (YY1 -  22554 *(Cb-128) - 46802*(Cr-128)) >> 16
+	//	B = (YY1 + 116130 *(Cb-128)                 ) >> 16
+	//
+	// The inputs (y, cb, cr) are 8 bit color, ranging in [0x00, 0xff]. In this
+	// function, the output is also 8 bit color, but in the related YCbCr.RGBA
+	// method, below, the output is 16 bit color, ranging in [0x0000, 0xffff].
+	// Outputting 16 bit color simply requires changing the 16 to 8 in the "R =
+	// etc >> 16" equation, and likewise for G and B.
+	//
+	// As mentioned above, a constant rounding adjustment of 1<<15 is a natural
+	// choice, but there is an additional constraint: if c0 := YCbCr{Y: y, Cb:
+	// 0x80, Cr: 0x80} and c1 := Gray{Y: y} then c0.RGBA() should equal
+	// c1.RGBA(). Specifically, if y == 0 then "R = etc >> 8" should yield
+	// 0x0000 and if y == 0xff then "R = etc >> 8" should yield 0xffff. If we
+	// used a constant rounding adjustment of 1<<15, then it would yield 0x0080
+	// and 0xff80 respectively.
+	//
+	// Note that when cb == 0x80 and cr == 0x80 then the formulae collapse to:
+	//	R = YY1 >> n
+	//	G = YY1 >> n
+	//	B = YY1 >> n
+	// where n is 16 for this function (8 bit color output) and 8 for the
+	// YCbCr.RGBA method (16 bit color output).
+	//
+	// The solution is to make the rounding adjustment non-constant, and equal
+	// to 257*Y', which ranges over [0, 1<<16-1] as Y' ranges over [0, 255].
+	// YY1 is then defined as:
+	//	YY1 = 65536*Y' + 257*Y'
+	// or equivalently:
+	//	YY1 = Y' * 0x10101
+	yy1 := int32(y) * 0x10101
 	cb1 := int32(cb) - 128
 	cr1 := int32(cr) - 128
 
@@ -136,7 +186,7 @@
 	//	0x7e18 0x808d 0x7db9
 	//	0x7e7e 0x8080 0x7d7d
 
-	yy1 := int32(c.Y) * 0x10100 // Convert 0x12 to 0x121200.
+	yy1 := int32(c.Y) * 0x10101
 	cb1 := int32(c.Cb) - 128
 	cr1 := int32(c.Cr) - 128
 
@@ -196,7 +246,7 @@
 
 func (c NYCbCrA) RGBA() (uint32, uint32, uint32, uint32) {
 	// The first part of this method is the same as YCbCr.RGBA.
-	yy1 := int32(c.Y) * 0x10100 // Convert 0x12 to 0x121200.
+	yy1 := int32(c.Y) * 0x10101
 	cb1 := int32(c.Cb) - 128
 	cr1 := int32(c.Cr) - 128
 
diff --git a/libgo/go/image/geom.go b/libgo/go/image/geom.go
index e1cd4dc..ed7dde2 100644
--- a/libgo/go/image/geom.go
+++ b/libgo/go/image/geom.go
@@ -161,7 +161,11 @@
 	if r.Max.Y > s.Max.Y {
 		r.Max.Y = s.Max.Y
 	}
-	if r.Min.X > r.Max.X || r.Min.Y > r.Max.Y {
+	// Letting r0 and s0 be the values of r and s at the time that the method
+	// is called, this next line is equivalent to:
+	//
+	// if max(r0.Min.X, s0.Min.X) >= min(r0.Max.X, s0.Max.X) || likewiseForY { etc }
+	if r.Empty() {
 		return ZR
 	}
 	return r
diff --git a/libgo/go/image/geom_test.go b/libgo/go/image/geom_test.go
index 6e9c6a1..9fede02 100644
--- a/libgo/go/image/geom_test.go
+++ b/libgo/go/image/geom_test.go
@@ -28,6 +28,7 @@
 
 	rects := []Rectangle{
 		Rect(0, 0, 10, 10),
+		Rect(10, 0, 20, 10),
 		Rect(1, 2, 3, 4),
 		Rect(4, 6, 10, 10),
 		Rect(2, 3, 12, 5),
@@ -62,9 +63,9 @@
 			if err := in(a, s); err != nil {
 				t.Errorf("Intersect: r=%s, s=%s, a=%s, a not in s: %v", r, s, a, err)
 			}
-			if a.Empty() == r.Overlaps(s) {
-				t.Errorf("Intersect: r=%s, s=%s, a=%s: empty=%t same as overlaps=%t",
-					r, s, a, a.Empty(), r.Overlaps(s))
+			if isZero, overlaps := a == (Rectangle{}), r.Overlaps(s); isZero == overlaps {
+				t.Errorf("Intersect: r=%s, s=%s, a=%s: isZero=%t same as overlaps=%t",
+					r, s, a, isZero, overlaps)
 			}
 			largerThanA := [4]Rectangle{a, a, a, a}
 			largerThanA[0].Min.X--
diff --git a/libgo/go/image/gif/reader.go b/libgo/go/image/gif/reader.go
index e611128..b1335e6 100644
--- a/libgo/go/image/gif/reader.go
+++ b/libgo/go/image/gif/reader.go
@@ -231,8 +231,8 @@
 				}
 				return errNotEnough
 			}
-			// Both lzwr and br should be exhausted. Reading from them should
-			// yield (0, io.EOF).
+			// In theory, both lzwr and br should be exhausted. Reading from them
+			// should yield (0, io.EOF).
 			//
 			// The spec (Appendix F - Compression), says that "An End of
 			// Information code... must be the last code output by the encoder
@@ -248,11 +248,21 @@
 				}
 				return errTooMuch
 			}
-			if n, err := br.Read(d.tmp[:1]); n != 0 || err != io.EOF {
+
+			// In practice, some GIFs have an extra byte in the data sub-block
+			// stream, which we ignore. See https://golang.org/issue/16146.
+			for nExtraBytes := 0; ; {
+				n, err := br.Read(d.tmp[:2])
+				nExtraBytes += n
+				if nExtraBytes > 1 {
+					return errTooMuch
+				}
+				if err == io.EOF {
+					break
+				}
 				if err != nil {
 					return fmt.Errorf("gif: reading image data: %v", err)
 				}
-				return errTooMuch
 			}
 
 			// Check that the color indexes are inside the palette.
@@ -410,14 +420,29 @@
 	height := int(d.tmp[6]) + int(d.tmp[7])<<8
 	d.imageFields = d.tmp[8]
 
-	// The GIF89a spec, Section 20 (Image Descriptor) says:
-	// "Each image must fit within the boundaries of the Logical
-	// Screen, as defined in the Logical Screen Descriptor."
-	bounds := image.Rect(left, top, left+width, top+height)
-	if bounds != bounds.Intersect(image.Rect(0, 0, d.width, d.height)) {
+	// The GIF89a spec, Section 20 (Image Descriptor) says: "Each image must
+	// fit within the boundaries of the Logical Screen, as defined in the
+	// Logical Screen Descriptor."
+	//
+	// This is conceptually similar to testing
+	//	frameBounds := image.Rect(left, top, left+width, top+height)
+	//	imageBounds := image.Rect(0, 0, d.width, d.height)
+	//	if !frameBounds.In(imageBounds) { etc }
+	// but the semantics of the Go image.Rectangle type is that r.In(s) is true
+	// whenever r is an empty rectangle, even if r.Min.X > s.Max.X. Here, we
+	// want something stricter.
+	//
+	// Note that, by construction, left >= 0 && top >= 0, so we only have to
+	// explicitly compare frameBounds.Max (left+width, top+height) against
+	// imageBounds.Max (d.width, d.height) and not frameBounds.Min (left, top)
+	// against imageBounds.Min (0, 0).
+	if left+width > d.width || top+height > d.height {
 		return nil, errors.New("gif: frame bounds larger than image bounds")
 	}
-	return image.NewPaletted(bounds, nil), nil
+	return image.NewPaletted(image.Rectangle{
+		Min: image.Point{left, top},
+		Max: image.Point{left + width, top + height},
+	}, nil), nil
 }
 
 func (d *decoder) readBlock() (int, error) {
diff --git a/libgo/go/image/gif/reader_test.go b/libgo/go/image/gif/reader_test.go
index 1267ba0..51c64b7 100644
--- a/libgo/go/image/gif/reader_test.go
+++ b/libgo/go/image/gif/reader_test.go
@@ -37,16 +37,35 @@
 }
 
 func TestDecode(t *testing.T) {
+	// extra contains superfluous bytes to inject into the GIF, either at the end
+	// of an existing data sub-block (past the LZW End of Information code) or in
+	// a separate data sub-block. The 0x02 values are arbitrary.
+	const extra = "\x02\x02\x02\x02"
+
 	testCases := []struct {
-		nPix    int  // The number of pixels in the image data.
-		extra   bool // Whether to write an extra block after the LZW-encoded data.
-		wantErr error
+		nPix int // The number of pixels in the image data.
+		// If non-zero, write this many extra bytes inside the data sub-block
+		// containing the LZW end code.
+		extraExisting int
+		// If non-zero, write an extra block of this many bytes.
+		extraSeparate int
+		wantErr       error
 	}{
-		{0, false, errNotEnough},
-		{1, false, errNotEnough},
-		{2, false, nil},
-		{2, true, errTooMuch},
-		{3, false, errTooMuch},
+		{0, 0, 0, errNotEnough},
+		{1, 0, 0, errNotEnough},
+		{2, 0, 0, nil},
+		// An extra data sub-block after the compressed section with 1 byte which we
+		// silently skip.
+		{2, 0, 1, nil},
+		// An extra data sub-block after the compressed section with 2 bytes. In
+		// this case we complain that there is too much data.
+		{2, 0, 2, errTooMuch},
+		// Too much pixel data.
+		{3, 0, 0, errTooMuch},
+		// An extra byte after LZW data, but inside the same data sub-block.
+		{2, 1, 0, nil},
+		// Two extra bytes after LZW data, but inside the same data sub-block.
+		{2, 2, 0, nil},
 	}
 	for _, tc := range testCases {
 		b := &bytes.Buffer{}
@@ -59,22 +78,35 @@
 		b.WriteString("\x2c\x00\x00\x00\x00\x02\x00\x01\x00\x00\x02")
 		if tc.nPix > 0 {
 			enc := lzwEncode(make([]byte, tc.nPix))
-			if len(enc) > 0xff {
-				t.Errorf("nPix=%d, extra=%t: compressed length %d is too large", tc.nPix, tc.extra, len(enc))
+			if len(enc)+tc.extraExisting > 0xff {
+				t.Errorf("nPix=%d, extraExisting=%d, extraSeparate=%d: compressed length %d is too large",
+					tc.nPix, tc.extraExisting, tc.extraSeparate, len(enc))
 				continue
 			}
-			b.WriteByte(byte(len(enc)))
+
+			// Write the size of the data sub-block containing the LZW data.
+			b.WriteByte(byte(len(enc) + tc.extraExisting))
+
+			// Write the LZW data.
 			b.Write(enc)
+
+			// Write extra bytes inside the same data sub-block where LZW data
+			// ended. Each arbitrarily 0x02.
+			b.WriteString(extra[:tc.extraExisting])
 		}
-		if tc.extra {
-			b.WriteString("\x01\x02") // A 1-byte payload with an 0x02 byte.
+
+		if tc.extraSeparate > 0 {
+			// Data sub-block size. This indicates how many extra bytes follow.
+			b.WriteByte(byte(tc.extraSeparate))
+			b.WriteString(extra[:tc.extraSeparate])
 		}
 		b.WriteByte(0x00) // An empty block signifies the end of the image data.
 		b.WriteString(trailerStr)
 
 		got, err := Decode(b)
 		if err != tc.wantErr {
-			t.Errorf("nPix=%d, extra=%t\ngot  %v\nwant %v", tc.nPix, tc.extra, err, tc.wantErr)
+			t.Errorf("nPix=%d, extraExisting=%d, extraSeparate=%d\ngot  %v\nwant %v",
+				tc.nPix, tc.extraExisting, tc.extraSeparate, err, tc.wantErr)
 		}
 
 		if tc.wantErr != nil {
@@ -90,7 +122,8 @@
 			},
 		}
 		if !reflect.DeepEqual(got, want) {
-			t.Errorf("nPix=%d, extra=%t\ngot  %v\nwant %v", tc.nPix, tc.extra, got, want)
+			t.Errorf("nPix=%d, extraExisting=%d, extraSeparate=%d\ngot  %v\nwant %v",
+				tc.nPix, tc.extraExisting, tc.extraSeparate, got, want)
 		}
 	}
 }
diff --git a/libgo/go/image/gif/writer.go b/libgo/go/image/gif/writer.go
index 1918196..493c754 100644
--- a/libgo/go/image/gif/writer.go
+++ b/libgo/go/image/gif/writer.go
@@ -132,7 +132,12 @@
 		e.buf[1] = e.g.BackgroundIndex
 		e.buf[2] = 0x00 // Pixel Aspect Ratio.
 		e.write(e.buf[:3])
-		e.globalCT = encodeColorTable(e.globalColorTable[:], p, paddedSize)
+		var err error
+		e.globalCT, err = encodeColorTable(e.globalColorTable[:], p, paddedSize)
+		if err != nil && e.err == nil {
+			e.err = err
+			return
+		}
 		e.write(e.globalColorTable[:e.globalCT])
 	} else {
 		// All frames have a local color table, so a global color table
@@ -149,8 +154,9 @@
 		e.buf[1] = 0xff // Application Label.
 		e.buf[2] = 0x0b // Block Size.
 		e.write(e.buf[:3])
-		_, e.err = io.WriteString(e.w, "NETSCAPE2.0") // Application Identifier.
-		if e.err != nil {
+		_, err := io.WriteString(e.w, "NETSCAPE2.0") // Application Identifier.
+		if err != nil && e.err == nil {
+			e.err = err
 			return
 		}
 		e.buf[0] = 0x03 // Block Size.
@@ -161,11 +167,18 @@
 	}
 }
 
-func encodeColorTable(dst []byte, p color.Palette, size int) int {
+func encodeColorTable(dst []byte, p color.Palette, size int) (int, error) {
+	if uint(size) >= uint(len(log2Lookup)) {
+		return 0, errors.New("gif: cannot encode color table with more than 256 entries")
+	}
 	n := log2Lookup[size]
 	for i := 0; i < n; i++ {
 		if i < len(p) {
-			r, g, b, _ := p[i].RGBA()
+			c := p[i]
+			if c == nil {
+				return 0, errors.New("gif: cannot encode color table with nil entries")
+			}
+			r, g, b, _ := c.RGBA()
 			dst[3*i+0] = uint8(r >> 8)
 			dst[3*i+1] = uint8(g >> 8)
 			dst[3*i+2] = uint8(b >> 8)
@@ -176,7 +189,7 @@
 			dst[3*i+2] = 0x00
 		}
 	}
-	return 3 * n
+	return 3 * n, nil
 }
 
 func (e *encoder) writeImageBlock(pm *image.Paletted, delay int, disposal byte) {
@@ -201,6 +214,10 @@
 
 	transparentIndex := -1
 	for i, c := range pm.Palette {
+		if c == nil {
+			e.err = errors.New("gif: cannot encode color table with nil entries")
+			return
+		}
 		if _, _, _, a := c.RGBA(); a == 0 {
 			transparentIndex = i
 			break
@@ -235,8 +252,12 @@
 	e.write(e.buf[:9])
 
 	paddedSize := log2(len(pm.Palette)) // Size of Local Color Table: 2^(1+n).
-	ct := encodeColorTable(e.localColorTable[:], pm.Palette, paddedSize)
-	if ct != e.globalCT || !bytes.Equal(e.globalColorTable[:ct], e.localColorTable[:ct]) {
+	if ct, err := encodeColorTable(e.localColorTable[:], pm.Palette, paddedSize); err != nil {
+		if e.err == nil {
+			e.err = err
+		}
+		return
+	} else if ct != e.globalCT || !bytes.Equal(e.globalColorTable[:ct], e.localColorTable[:ct]) {
 		// Use a local color table.
 		e.writeByte(fColorTable | uint8(paddedSize))
 		e.write(e.localColorTable[:ct])
@@ -253,7 +274,7 @@
 
 	lzww := lzw.NewWriter(blockWriter{e: e}, lzw.LSB, litWidth)
 	if dx := b.Dx(); dx == pm.Stride {
-		_, e.err = lzww.Write(pm.Pix)
+		_, e.err = lzww.Write(pm.Pix[:dx*b.Dy()])
 		if e.err != nil {
 			lzww.Close()
 			return
diff --git a/libgo/go/image/gif/writer_test.go b/libgo/go/image/gif/writer_test.go
index 775ccea..1bba9b8 100644
--- a/libgo/go/image/gif/writer_test.go
+++ b/libgo/go/image/gif/writer_test.go
@@ -438,6 +438,67 @@
 	}
 }
 
+func TestEncodeBadPalettes(t *testing.T) {
+	const w, h = 5, 5
+	for _, n := range []int{256, 257} {
+		for _, nilColors := range []bool{false, true} {
+			pal := make(color.Palette, n)
+			if !nilColors {
+				for i := range pal {
+					pal[i] = color.Black
+				}
+			}
+
+			err := EncodeAll(ioutil.Discard, &GIF{
+				Image: []*image.Paletted{
+					image.NewPaletted(image.Rect(0, 0, w, h), pal),
+				},
+				Delay:    make([]int, 1),
+				Disposal: make([]byte, 1),
+				Config: image.Config{
+					ColorModel: pal,
+					Width:      w,
+					Height:     h,
+				},
+			})
+
+			got := err != nil
+			want := n > 256 || nilColors
+			if got != want {
+				t.Errorf("n=%d, nilColors=%t: err != nil: got %t, want %t", n, nilColors, got, want)
+			}
+		}
+	}
+}
+
+func TestEncodeCroppedSubImages(t *testing.T) {
+	// This test means to ensure that Encode honors the Bounds and Strides of
+	// images correctly when encoding.
+	whole := image.NewPaletted(image.Rect(0, 0, 100, 100), palette.Plan9)
+	subImages := []image.Rectangle{
+		image.Rect(0, 0, 50, 50),
+		image.Rect(50, 0, 100, 50),
+		image.Rect(0, 50, 50, 50),
+		image.Rect(50, 50, 100, 100),
+		image.Rect(25, 25, 75, 75),
+		image.Rect(0, 0, 100, 50),
+		image.Rect(0, 50, 100, 100),
+		image.Rect(0, 0, 50, 100),
+		image.Rect(50, 0, 100, 100),
+	}
+	for _, sr := range subImages {
+		si := whole.SubImage(sr)
+		buf := bytes.NewBuffer(nil)
+		if err := Encode(buf, si, nil); err != nil {
+			t.Errorf("Encode: sr=%v: %v", sr, err)
+			continue
+		}
+		if _, err := Decode(buf); err != nil {
+			t.Errorf("Decode: sr=%v: %v", sr, err)
+		}
+	}
+}
+
 func BenchmarkEncode(b *testing.B) {
 	b.StopTimer()
 
diff --git a/libgo/go/image/image_test.go b/libgo/go/image/image_test.go
index 799c1a7..08ba61e 100644
--- a/libgo/go/image/image_test.go
+++ b/libgo/go/image/image_test.go
@@ -16,7 +16,7 @@
 	SubImage(Rectangle) Image
 }
 
-func cmp(t *testing.T, cm color.Model, c0, c1 color.Color) bool {
+func cmp(cm color.Model, c0, c1 color.Color) bool {
 	r0, g0, b0, a0 := cm.Convert(c0).RGBA()
 	r1, g1, b1, a1 := cm.Convert(c1).RGBA()
 	return r0 == r1 && g0 == g1 && b0 == b1 && a0 == a1
@@ -42,12 +42,12 @@
 			t.Errorf("%T: want bounds %v, got %v", m, Rect(0, 0, 10, 10), m.Bounds())
 			continue
 		}
-		if !cmp(t, m.ColorModel(), Transparent, m.At(6, 3)) {
+		if !cmp(m.ColorModel(), Transparent, m.At(6, 3)) {
 			t.Errorf("%T: at (6, 3), want a zero color, got %v", m, m.At(6, 3))
 			continue
 		}
 		m.Set(6, 3, Opaque)
-		if !cmp(t, m.ColorModel(), Opaque, m.At(6, 3)) {
+		if !cmp(m.ColorModel(), Opaque, m.At(6, 3)) {
 			t.Errorf("%T: at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
 			continue
 		}
@@ -60,16 +60,16 @@
 			t.Errorf("%T: sub-image want bounds %v, got %v", m, Rect(3, 2, 9, 8), m.Bounds())
 			continue
 		}
-		if !cmp(t, m.ColorModel(), Opaque, m.At(6, 3)) {
+		if !cmp(m.ColorModel(), Opaque, m.At(6, 3)) {
 			t.Errorf("%T: sub-image at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
 			continue
 		}
-		if !cmp(t, m.ColorModel(), Transparent, m.At(3, 3)) {
+		if !cmp(m.ColorModel(), Transparent, m.At(3, 3)) {
 			t.Errorf("%T: sub-image at (3, 3), want a zero color, got %v", m, m.At(3, 3))
 			continue
 		}
 		m.Set(3, 3, Opaque)
-		if !cmp(t, m.ColorModel(), Opaque, m.At(3, 3)) {
+		if !cmp(m.ColorModel(), Opaque, m.At(3, 3)) {
 			t.Errorf("%T: sub-image at (3, 3), want a non-zero color, got %v", m, m.At(3, 3))
 			continue
 		}
diff --git a/libgo/go/image/internal/imageutil/gen.go b/libgo/go/image/internal/imageutil/gen.go
index 6792b28..8b2c427 100644
--- a/libgo/go/image/internal/imageutil/gen.go
+++ b/libgo/go/image/internal/imageutil/gen.go
@@ -95,7 +95,7 @@
 			%s
 
 				// This is an inline version of image/color/ycbcr.go's func YCbCrToRGB.
-				yy1 := int32(src.Y[yi]) * 0x010100 // Convert 0x12 to 0x121200.
+				yy1 := int32(src.Y[yi]) * 0x10101
 				cb1 := int32(src.Cb[ci]) - 128
 				cr1 := int32(src.Cr[ci]) - 128
 
diff --git a/libgo/go/image/internal/imageutil/impl.go b/libgo/go/image/internal/imageutil/impl.go
index 3696b08..cfd5047 100644
--- a/libgo/go/image/internal/imageutil/impl.go
+++ b/libgo/go/image/internal/imageutil/impl.go
@@ -44,7 +44,7 @@
 			for x := x0; x != x1; x, yi, ci = x+4, yi+1, ci+1 {
 
 				// This is an inline version of image/color/ycbcr.go's func YCbCrToRGB.
-				yy1 := int32(src.Y[yi]) * 0x010100 // Convert 0x12 to 0x121200.
+				yy1 := int32(src.Y[yi]) * 0x10101
 				cb1 := int32(src.Cb[ci]) - 128
 				cr1 := int32(src.Cr[ci]) - 128
 
@@ -101,7 +101,7 @@
 				ci := ciBase + sx/2
 
 				// This is an inline version of image/color/ycbcr.go's func YCbCrToRGB.
-				yy1 := int32(src.Y[yi]) * 0x010100 // Convert 0x12 to 0x121200.
+				yy1 := int32(src.Y[yi]) * 0x10101
 				cb1 := int32(src.Cb[ci]) - 128
 				cr1 := int32(src.Cr[ci]) - 128
 
@@ -158,7 +158,7 @@
 				ci := ciBase + sx/2
 
 				// This is an inline version of image/color/ycbcr.go's func YCbCrToRGB.
-				yy1 := int32(src.Y[yi]) * 0x010100 // Convert 0x12 to 0x121200.
+				yy1 := int32(src.Y[yi]) * 0x10101
 				cb1 := int32(src.Cb[ci]) - 128
 				cr1 := int32(src.Cr[ci]) - 128
 
@@ -214,7 +214,7 @@
 			for x := x0; x != x1; x, yi, ci = x+4, yi+1, ci+1 {
 
 				// This is an inline version of image/color/ycbcr.go's func YCbCrToRGB.
-				yy1 := int32(src.Y[yi]) * 0x010100 // Convert 0x12 to 0x121200.
+				yy1 := int32(src.Y[yi]) * 0x10101
 				cb1 := int32(src.Cb[ci]) - 128
 				cr1 := int32(src.Cr[ci]) - 128
 
diff --git a/libgo/go/image/jpeg/huffman.go b/libgo/go/image/jpeg/huffman.go
index 4f8fe8e..95aaf71 100644
--- a/libgo/go/image/jpeg/huffman.go
+++ b/libgo/go/image/jpeg/huffman.go
@@ -101,7 +101,8 @@
 			return FormatError("bad Tc value")
 		}
 		th := d.tmp[0] & 0x0f
-		if th > maxTh || !d.progressive && th > 1 {
+		// The baseline th <= 1 restriction is specified in table B.5.
+		if th > maxTh || (d.baseline && th > 1) {
 			return FormatError("bad Th value")
 		}
 		h := &d.huff[tc][th]
diff --git a/libgo/go/image/jpeg/reader.go b/libgo/go/image/jpeg/reader.go
index c583421..a915e96 100644
--- a/libgo/go/image/jpeg/reader.go
+++ b/libgo/go/image/jpeg/reader.go
@@ -48,7 +48,7 @@
 )
 
 const (
-	sof0Marker = 0xc0 // Start Of Frame (Baseline).
+	sof0Marker = 0xc0 // Start Of Frame (Baseline Sequential).
 	sof1Marker = 0xc1 // Start Of Frame (Extended Sequential).
 	sof2Marker = 0xc2 // Start Of Frame (Progressive).
 	dhtMarker  = 0xc4 // Define Huffman Table.
@@ -126,9 +126,17 @@
 	blackPix    []byte
 	blackStride int
 
-	ri                  int // Restart Interval.
-	nComp               int
-	progressive         bool
+	ri    int // Restart Interval.
+	nComp int
+
+	// As per section 4.5, there are four modes of operation (selected by the
+	// SOF? markers): sequential DCT, progressive DCT, lossless and
+	// hierarchical, although this implementation does not support the latter
+	// two non-DCT modes. Sequential DCT is further split into baseline and
+	// extended, as per section 4.11.
+	baseline    bool
+	progressive bool
+
 	jfif                bool
 	adobeTransformValid bool
 	adobeTransform      uint8
@@ -596,6 +604,7 @@
 
 		switch marker {
 		case sof0Marker, sof1Marker, sof2Marker:
+			d.baseline = marker == sof0Marker
 			d.progressive = marker == sof2Marker
 			err = d.processSOF(n)
 			if configOnly && d.jfif {
diff --git a/libgo/go/image/jpeg/scan.go b/libgo/go/image/jpeg/scan.go
index e1104d2..712e7e3 100644
--- a/libgo/go/image/jpeg/scan.go
+++ b/libgo/go/image/jpeg/scan.go
@@ -92,12 +92,13 @@
 		}
 		totalHV += d.comp[compIndex].h * d.comp[compIndex].v
 
+		// The baseline t <= 1 restriction is specified in table B.3.
 		scan[i].td = d.tmp[2+2*i] >> 4
-		if scan[i].td > maxTh {
+		if t := scan[i].td; t > maxTh || (d.baseline && t > 1) {
 			return FormatError("bad Td value")
 		}
 		scan[i].ta = d.tmp[2+2*i] & 0x0f
-		if scan[i].ta > maxTh {
+		if t := scan[i].ta; t > maxTh || (d.baseline && t > 1) {
 			return FormatError("bad Ta value")
 		}
 	}
@@ -122,7 +123,8 @@
 	// by the second-least significant bit, followed by the least
 	// significant bit.
 	//
-	// For baseline JPEGs, these parameters are hard-coded to 0/63/0/0.
+	// For sequential JPEGs, these parameters are hard-coded to 0/63/0/0, as
+	// per table B.3.
 	zigStart, zigEnd, ah, al := int32(0), int32(blockSize-1), uint32(0), uint32(0)
 	if d.progressive {
 		zigStart = int32(d.tmp[1+2*nComp])
@@ -177,7 +179,7 @@
 					// The blocks are traversed one MCU at a time. For 4:2:0 chroma
 					// subsampling, there are four Y 8x8 blocks in every 16x16 MCU.
 					//
-					// For a baseline 32x16 pixel image, the Y blocks visiting order is:
+					// For a sequential 32x16 pixel image, the Y blocks visiting order is:
 					//	0 1 4 5
 					//	2 3 6 7
 					//
diff --git a/libgo/go/image/jpeg/writer.go b/libgo/go/image/jpeg/writer.go
index 91bbde3..a600499 100644
--- a/libgo/go/image/jpeg/writer.go
+++ b/libgo/go/image/jpeg/writer.go
@@ -311,7 +311,7 @@
 	}
 }
 
-// writeSOF0 writes the Start Of Frame (Baseline) marker.
+// writeSOF0 writes the Start Of Frame (Baseline Sequential) marker.
 func (e *encoder) writeSOF0(size image.Point, nComponent int) {
 	markerlen := 8 + 3*nComponent
 	e.writeMarkerHeader(sof0Marker, markerlen)
@@ -441,6 +441,30 @@
 	}
 }
 
+// yCbCrToYCbCr is a specialized version of toYCbCr for image.YCbCr images.
+func yCbCrToYCbCr(m *image.YCbCr, p image.Point, yBlock, cbBlock, crBlock *block) {
+	b := m.Bounds()
+	xmax := b.Max.X - 1
+	ymax := b.Max.Y - 1
+	for j := 0; j < 8; j++ {
+		sy := p.Y + j
+		if sy > ymax {
+			sy = ymax
+		}
+		for i := 0; i < 8; i++ {
+			sx := p.X + i
+			if sx > xmax {
+				sx = xmax
+			}
+			yi := m.YOffset(sx, sy)
+			ci := m.COffset(sx, sy)
+			yBlock[8*j+i] = int32(m.Y[yi])
+			cbBlock[8*j+i] = int32(m.Cb[ci])
+			crBlock[8*j+i] = int32(m.Cr[ci])
+		}
+	}
+}
+
 // scale scales the 16x16 region represented by the 4 src blocks to the 8x8
 // dst block.
 func scale(dst *block, src *[4]block) {
@@ -510,6 +534,7 @@
 		}
 	default:
 		rgba, _ := m.(*image.RGBA)
+		ycbcr, _ := m.(*image.YCbCr)
 		for y := bounds.Min.Y; y < bounds.Max.Y; y += 16 {
 			for x := bounds.Min.X; x < bounds.Max.X; x += 16 {
 				for i := 0; i < 4; i++ {
@@ -518,6 +543,8 @@
 					p := image.Pt(x+xOff, y+yOff)
 					if rgba != nil {
 						rgbaToYCbCr(rgba, p, &b, &cb[i], &cr[i])
+					} else if ycbcr != nil {
+						yCbCrToYCbCr(ycbcr, p, &b, &cb[i], &cr[i])
 					} else {
 						toYCbCr(m, p, &b, &cb[i], &cr[i])
 					}
diff --git a/libgo/go/image/jpeg/writer_test.go b/libgo/go/image/jpeg/writer_test.go
index 3df3cfc..a6c0561 100644
--- a/libgo/go/image/jpeg/writer_test.go
+++ b/libgo/go/image/jpeg/writer_test.go
@@ -208,7 +208,41 @@
 	return sum / n
 }
 
-func BenchmarkEncode(b *testing.B) {
+func TestEncodeYCbCr(t *testing.T) {
+	bo := image.Rect(0, 0, 640, 480)
+	imgRGBA := image.NewRGBA(bo)
+	// Must use 444 subsampling to avoid lossy RGBA to YCbCr conversion.
+	imgYCbCr := image.NewYCbCr(bo, image.YCbCrSubsampleRatio444)
+	rnd := rand.New(rand.NewSource(123))
+	// Create identical rgba and ycbcr images.
+	for y := bo.Min.Y; y < bo.Max.Y; y++ {
+		for x := bo.Min.X; x < bo.Max.X; x++ {
+			col := color.RGBA{
+				uint8(rnd.Intn(256)),
+				uint8(rnd.Intn(256)),
+				uint8(rnd.Intn(256)),
+				255,
+			}
+			imgRGBA.SetRGBA(x, y, col)
+			yo := imgYCbCr.YOffset(x, y)
+			co := imgYCbCr.COffset(x, y)
+			cy, ccr, ccb := color.RGBToYCbCr(col.R, col.G, col.B)
+			imgYCbCr.Y[yo] = cy
+			imgYCbCr.Cb[co] = ccr
+			imgYCbCr.Cr[co] = ccb
+		}
+	}
+
+	// Now check that both images are identical after an encode.
+	var bufRGBA, bufYCbCr bytes.Buffer
+	Encode(&bufRGBA, imgRGBA, nil)
+	Encode(&bufYCbCr, imgYCbCr, nil)
+	if !bytes.Equal(bufRGBA.Bytes(), bufYCbCr.Bytes()) {
+		t.Errorf("RGBA and YCbCr encoded bytes differ")
+	}
+}
+
+func BenchmarkEncodeRGBA(b *testing.B) {
 	b.StopTimer()
 	img := image.NewRGBA(image.Rect(0, 0, 640, 480))
 	bo := img.Bounds()
@@ -230,3 +264,25 @@
 		Encode(ioutil.Discard, img, options)
 	}
 }
+
+func BenchmarkEncodeYCbCr(b *testing.B) {
+	b.StopTimer()
+	img := image.NewYCbCr(image.Rect(0, 0, 640, 480), image.YCbCrSubsampleRatio420)
+	bo := img.Bounds()
+	rnd := rand.New(rand.NewSource(123))
+	for y := bo.Min.Y; y < bo.Max.Y; y++ {
+		for x := bo.Min.X; x < bo.Max.X; x++ {
+			cy := img.YOffset(x, y)
+			ci := img.COffset(x, y)
+			img.Y[cy] = uint8(rnd.Intn(256))
+			img.Cb[ci] = uint8(rnd.Intn(256))
+			img.Cr[ci] = uint8(rnd.Intn(256))
+		}
+	}
+	b.SetBytes(640 * 480 * 3)
+	b.StartTimer()
+	options := &Options{Quality: 90}
+	for i := 0; i < b.N; i++ {
+		Encode(ioutil.Discard, img, options)
+	}
+}
diff --git a/libgo/go/image/png/reader.go b/libgo/go/image/png/reader.go
index 8299df5..4f043a0 100644
--- a/libgo/go/image/png/reader.go
+++ b/libgo/go/image/png/reader.go
@@ -613,12 +613,19 @@
 			}
 		case cbG8:
 			if d.useTransparent {
-				// Match error from Go 1.7 and earlier.
-				// Go 1.9 will decode this properly.
-				return nil, chunkOrderError
+				ty := d.transparent[1]
+				for x := 0; x < width; x++ {
+					ycol := cdat[x]
+					acol := uint8(0xff)
+					if ycol == ty {
+						acol = 0x00
+					}
+					nrgba.SetNRGBA(x, y, color.NRGBA{ycol, ycol, ycol, acol})
+				}
+			} else {
+				copy(gray.Pix[pixOffset:], cdat)
+				pixOffset += gray.Stride
 			}
-			copy(gray.Pix[pixOffset:], cdat)
-			pixOffset += gray.Stride
 		case cbGA8:
 			for x := 0; x < width; x++ {
 				ycol := cdat[2*x+0]
diff --git a/libgo/go/image/png/reader_test.go b/libgo/go/image/png/reader_test.go
index 503b5dc..cabf533 100644
--- a/libgo/go/image/png/reader_test.go
+++ b/libgo/go/image/png/reader_test.go
@@ -588,6 +588,67 @@
 	}
 }
 
+func TestGray8Transparent(t *testing.T) {
+	// These bytes come from https://github.com/golang/go/issues/19553
+	m, err := Decode(bytes.NewReader([]byte{
+		0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a, 0x00, 0x00, 0x00, 0x0d, 0x49, 0x48, 0x44, 0x52,
+		0x00, 0x00, 0x00, 0x0f, 0x00, 0x00, 0x00, 0x0b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x85, 0x2c, 0x88,
+		0x80, 0x00, 0x00, 0x00, 0x02, 0x74, 0x52, 0x4e, 0x53, 0x00, 0xff, 0x5b, 0x91, 0x22, 0xb5, 0x00,
+		0x00, 0x00, 0x02, 0x62, 0x4b, 0x47, 0x44, 0x00, 0xff, 0x87, 0x8f, 0xcc, 0xbf, 0x00, 0x00, 0x00,
+		0x09, 0x70, 0x48, 0x59, 0x73, 0x00, 0x00, 0x0a, 0xf0, 0x00, 0x00, 0x0a, 0xf0, 0x01, 0x42, 0xac,
+		0x34, 0x98, 0x00, 0x00, 0x00, 0x07, 0x74, 0x49, 0x4d, 0x45, 0x07, 0xd5, 0x04, 0x02, 0x12, 0x11,
+		0x11, 0xf7, 0x65, 0x3d, 0x8b, 0x00, 0x00, 0x00, 0x4f, 0x49, 0x44, 0x41, 0x54, 0x08, 0xd7, 0x63,
+		0xf8, 0xff, 0xff, 0xff, 0xb9, 0xbd, 0x70, 0xf0, 0x8c, 0x01, 0xc8, 0xaf, 0x6e, 0x99, 0x02, 0x05,
+		0xd9, 0x7b, 0xc1, 0xfc, 0x6b, 0xff, 0xa1, 0xa0, 0x87, 0x30, 0xff, 0xd9, 0xde, 0xbd, 0xd5, 0x4b,
+		0xf7, 0xee, 0xfd, 0x0e, 0xe3, 0xef, 0xcd, 0x06, 0x19, 0x14, 0xf5, 0x1e, 0xce, 0xef, 0x01, 0x31,
+		0x92, 0xd7, 0x82, 0x41, 0x31, 0x9c, 0x3f, 0x07, 0x02, 0xee, 0xa1, 0xaa, 0xff, 0xff, 0x9f, 0xe1,
+		0xd9, 0x56, 0x30, 0xf8, 0x0e, 0xe5, 0x03, 0x00, 0xa9, 0x42, 0x84, 0x3d, 0xdf, 0x8f, 0xa6, 0x8f,
+		0x00, 0x00, 0x00, 0x00, 0x49, 0x45, 0x4e, 0x44, 0xae, 0x42, 0x60, 0x82,
+	}))
+	if err != nil {
+		t.Fatalf("Decode: %v", err)
+	}
+
+	const hex = "0123456789abcdef"
+	var got []byte
+	bounds := m.Bounds()
+	for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
+		for x := bounds.Min.X; x < bounds.Max.X; x++ {
+			if r, _, _, a := m.At(x, y).RGBA(); a != 0 {
+				got = append(got,
+					hex[0x0f&(r>>12)],
+					hex[0x0f&(r>>8)],
+					' ',
+				)
+			} else {
+				got = append(got,
+					'.',
+					'.',
+					' ',
+				)
+			}
+		}
+		got = append(got, '\n')
+	}
+
+	const want = "" +
+		".. .. .. ce bd bd bd bd bd bd bd bd bd bd e6 \n" +
+		".. .. .. 7b 84 94 94 94 94 94 94 94 94 6b bd \n" +
+		".. .. .. 7b d6 .. .. .. .. .. .. .. .. 8c bd \n" +
+		".. .. .. 7b d6 .. .. .. .. .. .. .. .. 8c bd \n" +
+		".. .. .. 7b d6 .. .. .. .. .. .. .. .. 8c bd \n" +
+		"e6 bd bd 7b a5 bd bd f7 .. .. .. .. .. 8c bd \n" +
+		"bd 6b 94 94 94 94 5a ef .. .. .. .. .. 8c bd \n" +
+		"bd 8c .. .. .. .. 63 ad ad ad ad ad ad 73 bd \n" +
+		"bd 8c .. .. .. .. 63 9c 9c 9c 9c 9c 9c 9c de \n" +
+		"bd 6b 94 94 94 94 5a ef .. .. .. .. .. .. .. \n" +
+		"e6 b5 b5 b5 b5 b5 b5 f7 .. .. .. .. .. .. .. \n"
+
+	if string(got) != want {
+		t.Errorf("got:\n%swant:\n%s", got, want)
+	}
+}
+
 func benchmarkDecode(b *testing.B, filename string, bytesPerPixel int) {
 	b.StopTimer()
 	data, err := ioutil.ReadFile(filename)
@@ -629,13 +690,3 @@
 func BenchmarkDecodeInterlacing(b *testing.B) {
 	benchmarkDecode(b, "testdata/benchRGB-interlace.png", 4)
 }
-
-func TestIssue19553(t *testing.T) {
-	var buf = []byte{
-		0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a, 0x00, 0x00, 0x00, 0x0d, 0x49, 0x48, 0x44, 0x52, 0x00, 0x00, 0x00, 0x0f, 0x00, 0x00, 0x00, 0x0b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x85, 0x2c, 0x88, 0x80, 0x00, 0x00, 0x00, 0x02, 0x74, 0x52, 0x4e, 0x53, 0x00, 0xff, 0x5b, 0x91, 0x22, 0xb5, 0x00, 0x00, 0x00, 0x02, 0x62, 0x4b, 0x47, 0x44, 0x00, 0xff, 0x87, 0x8f, 0xcc, 0xbf, 0x00, 0x00, 0x00, 0x09, 0x70, 0x48, 0x59, 0x73, 0x00, 0x00, 0x0a, 0xf0, 0x00, 0x00, 0x0a, 0xf0, 0x01, 0x42, 0xac, 0x34, 0x98, 0x00, 0x00, 0x00, 0x07, 0x74, 0x49, 0x4d, 0x45, 0x07, 0xd5, 0x04, 0x02, 0x12, 0x11, 0x11, 0xf7, 0x65, 0x3d, 0x8b, 0x00, 0x00, 0x00, 0x4f, 0x49, 0x44, 0x41, 0x54, 0x08, 0xd7, 0x63, 0xf8, 0xff, 0xff, 0xff, 0xb9, 0xbd, 0x70, 0xf0, 0x8c, 0x01, 0xc8, 0xaf, 0x6e, 0x99, 0x02, 0x05, 0xd9, 0x7b, 0xc1, 0xfc, 0x6b, 0xff, 0xa1, 0xa0, 0x87, 0x30, 0xff, 0xd9, 0xde, 0xbd, 0xd5, 0x4b, 0xf7, 0xee, 0xfd, 0x0e, 0xe3, 0xef, 0xcd, 0x06, 0x19, 0x14, 0xf5, 0x1e, 0xce, 0xef, 0x01, 0x31, 0x92, 0xd7, 0x82, 0x41, 0x31, 0x9c, 0x3f, 0x07, 0x02, 0xee, 0xa1, 0xaa, 0xff, 0xff, 0x9f, 0xe1, 0xd9, 0x56, 0x30, 0xf8, 0x0e, 0xe5, 0x03, 0x00, 0xa9, 0x42, 0x84, 0x3d, 0xdf, 0x8f, 0xa6, 0x8f, 0x00, 0x00, 0x00, 0x00, 0x49, 0x45, 0x4e, 0x44, 0xae, 0x42, 0x60, 0x82,
-	}
-	_, err := Decode(bytes.NewReader(buf))
-	if err != chunkOrderError {
-		t.Errorf("Decode: expected chunkOrderError for transparent gray8, got %v", err)
-	}
-}
diff --git a/libgo/go/image/png/writer.go b/libgo/go/image/png/writer.go
index dd87d81..49f1ad2 100644
--- a/libgo/go/image/png/writer.go
+++ b/libgo/go/image/png/writer.go
@@ -17,17 +17,37 @@
 // Encoder configures encoding PNG images.
 type Encoder struct {
 	CompressionLevel CompressionLevel
+
+	// BufferPool optionally specifies a buffer pool to get temporary
+	// EncoderBuffers when encoding an image.
+	BufferPool EncoderBufferPool
 }
 
+// EncoderBufferPool is an interface for getting and returning temporary
+// instances of the EncoderBuffer struct. This can be used to reuse buffers
+// when encoding multiple images.
+type EncoderBufferPool interface {
+	Get() *EncoderBuffer
+	Put(*EncoderBuffer)
+}
+
+// EncoderBuffer holds the buffers used for encoding PNG images.
+type EncoderBuffer encoder
+
 type encoder struct {
-	enc    *Encoder
-	w      io.Writer
-	m      image.Image
-	cb     int
-	err    error
-	header [8]byte
-	footer [4]byte
-	tmp    [4 * 256]byte
+	enc     *Encoder
+	w       io.Writer
+	m       image.Image
+	cb      int
+	err     error
+	header  [8]byte
+	footer  [4]byte
+	tmp     [4 * 256]byte
+	cr      [nFilter][]uint8
+	pr      []uint8
+	zw      *zlib.Writer
+	zwLevel int
+	bw      *bufio.Writer
 }
 
 type CompressionLevel int
@@ -273,12 +293,24 @@
 	return filter
 }
 
-func writeImage(w io.Writer, m image.Image, cb int, level int) error {
-	zw, err := zlib.NewWriterLevel(w, level)
-	if err != nil {
-		return err
+func zeroMemory(v []uint8) {
+	for i := range v {
+		v[i] = 0
 	}
-	defer zw.Close()
+}
+
+func (e *encoder) writeImage(w io.Writer, m image.Image, cb int, level int) error {
+	if e.zw == nil || e.zwLevel != level {
+		zw, err := zlib.NewWriterLevel(w, level)
+		if err != nil {
+			return err
+		}
+		e.zw = zw
+		e.zwLevel = level
+	} else {
+		e.zw.Reset(w)
+	}
+	defer e.zw.Close()
 
 	bpp := 0 // Bytes per pixel.
 
@@ -304,12 +336,23 @@
 	// other PNG filter types. These buffers are allocated once and re-used for each row.
 	// The +1 is for the per-row filter type, which is at cr[*][0].
 	b := m.Bounds()
-	var cr [nFilter][]uint8
-	for i := range cr {
-		cr[i] = make([]uint8, 1+bpp*b.Dx())
-		cr[i][0] = uint8(i)
+	sz := 1 + bpp*b.Dx()
+	for i := range e.cr {
+		if cap(e.cr[i]) < sz {
+			e.cr[i] = make([]uint8, sz)
+		} else {
+			e.cr[i] = e.cr[i][:sz]
+		}
+		e.cr[i][0] = uint8(i)
 	}
-	pr := make([]uint8, 1+bpp*b.Dx())
+	cr := e.cr
+	if cap(e.pr) < sz {
+		e.pr = make([]uint8, sz)
+	} else {
+		e.pr = e.pr[:sz]
+		zeroMemory(e.pr)
+	}
+	pr := e.pr
 
 	gray, _ := m.(*image.Gray)
 	rgba, _ := m.(*image.RGBA)
@@ -429,7 +472,7 @@
 		}
 
 		// Write the compressed bytes.
-		if _, err := zw.Write(cr[f]); err != nil {
+		if _, err := e.zw.Write(cr[f]); err != nil {
 			return err
 		}
 
@@ -444,13 +487,16 @@
 	if e.err != nil {
 		return
 	}
-	var bw *bufio.Writer
-	bw = bufio.NewWriterSize(e, 1<<15)
-	e.err = writeImage(bw, e.m, e.cb, levelToZlib(e.enc.CompressionLevel))
+	if e.bw == nil {
+		e.bw = bufio.NewWriterSize(e, 1<<15)
+	} else {
+		e.bw.Reset(e)
+	}
+	e.err = e.writeImage(e.bw, e.m, e.cb, levelToZlib(e.enc.CompressionLevel))
 	if e.err != nil {
 		return
 	}
-	e.err = bw.Flush()
+	e.err = e.bw.Flush()
 }
 
 // This function is required because we want the zero value of
@@ -489,7 +535,19 @@
 		return FormatError("invalid image size: " + strconv.FormatInt(mw, 10) + "x" + strconv.FormatInt(mh, 10))
 	}
 
-	var e encoder
+	var e *encoder
+	if enc.BufferPool != nil {
+		buffer := enc.BufferPool.Get()
+		e = (*encoder)(buffer)
+
+	}
+	if e == nil {
+		e = &encoder{}
+	}
+	if enc.BufferPool != nil {
+		defer enc.BufferPool.Put((*EncoderBuffer)(e))
+	}
+
 	e.enc = enc
 	e.w = w
 	e.m = m
diff --git a/libgo/go/image/png/writer_test.go b/libgo/go/image/png/writer_test.go
index d67a815..b1f97b1 100644
--- a/libgo/go/image/png/writer_test.go
+++ b/libgo/go/image/png/writer_test.go
@@ -130,6 +130,31 @@
 	}
 }
 
+type pool struct {
+	b *EncoderBuffer
+}
+
+func (p *pool) Get() *EncoderBuffer {
+	return p.b
+}
+
+func (p *pool) Put(b *EncoderBuffer) {
+	p.b = b
+}
+
+func BenchmarkEncodeGrayWithBufferPool(b *testing.B) {
+	b.StopTimer()
+	img := image.NewGray(image.Rect(0, 0, 640, 480))
+	e := Encoder{
+		BufferPool: &pool{},
+	}
+	b.SetBytes(640 * 480 * 1)
+	b.StartTimer()
+	for i := 0; i < b.N; i++ {
+		e.Encode(ioutil.Discard, img)
+	}
+}
+
 func BenchmarkEncodeNRGBOpaque(b *testing.B) {
 	b.StopTimer()
 	img := image.NewNRGBA(image.Rect(0, 0, 640, 480))
diff --git a/libgo/go/internal/cpu/cpu.go b/libgo/go/internal/cpu/cpu.go
new file mode 100644
index 0000000..2226b77
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu.go
@@ -0,0 +1,32 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cpu implements processor feature detection
+// used by the Go standard libary.
+package cpu
+
+var X86 x86
+
+// The booleans in x86 contain the correspondingly named cpuid feature bit.
+// HasAVX and HasAVX2 are only set if the OS does support XMM and YMM registers
+// in addition to the cpuid feature bit being set.
+// The struct is padded to avoid false sharing.
+type x86 struct {
+	_            [CacheLineSize]byte
+	HasAES       bool
+	HasAVX       bool
+	HasAVX2      bool
+	HasBMI1      bool
+	HasBMI2      bool
+	HasERMS      bool
+	HasOSXSAVE   bool
+	HasPCLMULQDQ bool
+	HasPOPCNT    bool
+	HasSSE2      bool
+	HasSSE3      bool
+	HasSSSE3     bool
+	HasSSE41     bool
+	HasSSE42     bool
+	_            [CacheLineSize]byte
+}
diff --git a/libgo/go/internal/cpu/cpu_arm.go b/libgo/go/internal/cpu/cpu_arm.go
new file mode 100644
index 0000000..078a6c3
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_arm.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 32
diff --git a/libgo/go/internal/cpu/cpu_arm64.go b/libgo/go/internal/cpu/cpu_arm64.go
new file mode 100644
index 0000000..078a6c3
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_arm64.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 32
diff --git a/libgo/go/internal/cpu/cpu_mips.go b/libgo/go/internal/cpu/cpu_mips.go
new file mode 100644
index 0000000..078a6c3
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_mips.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 32
diff --git a/libgo/go/internal/cpu/cpu_mips64.go b/libgo/go/internal/cpu/cpu_mips64.go
new file mode 100644
index 0000000..078a6c3
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_mips64.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 32
diff --git a/libgo/go/internal/cpu/cpu_mips64le.go b/libgo/go/internal/cpu/cpu_mips64le.go
new file mode 100644
index 0000000..078a6c3
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_mips64le.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 32
diff --git a/libgo/go/internal/cpu/cpu_mipsle.go b/libgo/go/internal/cpu/cpu_mipsle.go
new file mode 100644
index 0000000..078a6c3
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_mipsle.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 32
diff --git a/libgo/go/internal/cpu/cpu_ppc64.go b/libgo/go/internal/cpu/cpu_ppc64.go
new file mode 100644
index 0000000..5b15150
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_ppc64.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 128
diff --git a/libgo/go/internal/cpu/cpu_ppc64le.go b/libgo/go/internal/cpu/cpu_ppc64le.go
new file mode 100644
index 0000000..5b15150
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_ppc64le.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 128
diff --git a/libgo/go/internal/cpu/cpu_s390x.go b/libgo/go/internal/cpu/cpu_s390x.go
new file mode 100644
index 0000000..4455809
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_s390x.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+const CacheLineSize = 256
diff --git a/libgo/go/internal/cpu/cpu_test.go b/libgo/go/internal/cpu/cpu_test.go
new file mode 100644
index 0000000..ab9836a
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_test.go
@@ -0,0 +1,27 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu_test
+
+import (
+	"internal/cpu"
+	"runtime"
+	"testing"
+)
+
+func TestAMD64minimalFeatures(t *testing.T) {
+	if runtime.GOARCH == "amd64" {
+		if !cpu.X86.HasSSE2 {
+			t.Fatalf("HasSSE2 expected true, got false")
+		}
+	}
+}
+
+func TestAVX2hasAVX(t *testing.T) {
+	if runtime.GOARCH == "amd64" {
+		if cpu.X86.HasAVX2 && !cpu.X86.HasAVX {
+			t.Fatalf("HasAVX expected true, got false")
+		}
+	}
+}
diff --git a/libgo/go/internal/cpu/cpu_x86.go b/libgo/go/internal/cpu/cpu_x86.go
new file mode 100644
index 0000000..31e7084
--- /dev/null
+++ b/libgo/go/internal/cpu/cpu_x86.go
@@ -0,0 +1,59 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build 386 amd64 amd64p32
+
+package cpu
+
+const CacheLineSize = 64
+
+// cpuid is implemented in cpu_x86.s.
+func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
+
+// xgetbv with ecx = 0 is implemented in cpu_x86.s.
+func xgetbv() (eax, edx uint32)
+
+func init() {
+	maxId, _, _, _ := cpuid(0, 0)
+
+	if maxId < 1 {
+		return
+	}
+
+	_, _, ecx1, edx1 := cpuid(1, 0)
+	X86.HasSSE2 = isSet(26, edx1)
+
+	X86.HasSSE3 = isSet(0, ecx1)
+	X86.HasPCLMULQDQ = isSet(1, ecx1)
+	X86.HasSSSE3 = isSet(9, ecx1)
+	X86.HasSSE41 = isSet(19, ecx1)
+	X86.HasSSE42 = isSet(20, ecx1)
+	X86.HasPOPCNT = isSet(23, ecx1)
+	X86.HasAES = isSet(25, ecx1)
+	X86.HasOSXSAVE = isSet(27, ecx1)
+
+	osSupportsAVX := false
+	// For XGETBV, OSXSAVE bit is required and sufficient.
+	if X86.HasOSXSAVE {
+		eax, _ := xgetbv()
+		// Check if XMM and YMM registers have OS support.
+		osSupportsAVX = isSet(1, eax) && isSet(2, eax)
+	}
+
+	X86.HasAVX = isSet(28, ecx1) && osSupportsAVX
+
+	if maxId < 7 {
+		return
+	}
+
+	_, ebx7, _, _ := cpuid(7, 0)
+	X86.HasBMI1 = isSet(3, ebx7)
+	X86.HasAVX2 = isSet(5, ebx7) && osSupportsAVX
+	X86.HasBMI2 = isSet(8, ebx7)
+	X86.HasERMS = isSet(9, ebx7)
+}
+
+func isSet(bitpos uint, value uint32) bool {
+	return value&(1<<bitpos) != 0
+}
diff --git a/libgo/go/internal/poll/export_posix_test.go b/libgo/go/internal/poll/export_posix_test.go
new file mode 100644
index 0000000..73b2c11
--- /dev/null
+++ b/libgo/go/internal/poll/export_posix_test.go
@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
+
+// Export guts for testing on posix.
+// Since testing imports os and os imports internal/poll,
+// the internal/poll tests can not be in package poll.
+
+package poll
+
+func (fd *FD) EOFError(n int, err error) error {
+	return fd.eofError(n, err)
+}
diff --git a/libgo/go/internal/poll/export_test.go b/libgo/go/internal/poll/export_test.go
new file mode 100644
index 0000000..02664d9
--- /dev/null
+++ b/libgo/go/internal/poll/export_test.go
@@ -0,0 +1,35 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Export guts for testing.
+// Since testing imports os and os imports internal/poll,
+// the internal/poll tests can not be in package poll.
+
+package poll
+
+var Consume = consume
+
+type FDMutex struct {
+	fdMutex
+}
+
+func (mu *FDMutex) Incref() bool {
+	return mu.incref()
+}
+
+func (mu *FDMutex) IncrefAndClose() bool {
+	return mu.increfAndClose()
+}
+
+func (mu *FDMutex) Decref() bool {
+	return mu.decref()
+}
+
+func (mu *FDMutex) RWLock(read bool) bool {
+	return mu.rwlock(read)
+}
+
+func (mu *FDMutex) RWUnlock(read bool) bool {
+	return mu.rwunlock(read)
+}
diff --git a/libgo/go/internal/poll/fd.go b/libgo/go/internal/poll/fd.go
new file mode 100644
index 0000000..f1454db
--- /dev/null
+++ b/libgo/go/internal/poll/fd.go
@@ -0,0 +1,57 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package poll supports non-blocking I/O on file descriptors with polling.
+// This supports I/O operations that block only a goroutine, not a thread.
+// This is used by the net and os packages.
+// It uses a poller built into the runtime, with support from the
+// runtime scheduler.
+package poll
+
+import "errors"
+
+// ErrNetClosing is returned when a network descriptor is used after
+// it has been closed. Keep this string consistent because of issue
+// #4373: since historically programs have not been able to detect
+// this error, they look for the string.
+var ErrNetClosing = errors.New("use of closed network connection")
+
+// ErrFileClosing is returned when a file descriptor is used after it
+// has been closed.
+var ErrFileClosing = errors.New("use of closed file")
+
+// Return the appropriate closing error based on isFile.
+func errClosing(isFile bool) error {
+	if isFile {
+		return ErrFileClosing
+	}
+	return ErrNetClosing
+}
+
+// ErrTimeout is returned for an expired deadline.
+var ErrTimeout error = &TimeoutError{}
+
+// TimeoutError is returned for an expired deadline.
+type TimeoutError struct{}
+
+// Implement the net.Error interface.
+func (e *TimeoutError) Error() string   { return "i/o timeout" }
+func (e *TimeoutError) Timeout() bool   { return true }
+func (e *TimeoutError) Temporary() bool { return true }
+
+// consume removes data from a slice of byte slices, for writev.
+func consume(v *[][]byte, n int64) {
+	for len(*v) > 0 {
+		ln0 := int64(len((*v)[0]))
+		if ln0 > n {
+			(*v)[0] = (*v)[0][n:]
+			return
+		}
+		n -= ln0
+		*v = (*v)[1:]
+	}
+}
+
+// TestHookDidWritev is a hook for testing writev.
+var TestHookDidWritev = func(wrote int) {}
diff --git a/libgo/go/net/fd_io_plan9.go b/libgo/go/internal/poll/fd_io_plan9.go
similarity index 91%
rename from libgo/go/net/fd_io_plan9.go
rename to libgo/go/internal/poll/fd_io_plan9.go
index 76da0c5..287d11b 100644
--- a/libgo/go/net/fd_io_plan9.go
+++ b/libgo/go/internal/poll/fd_io_plan9.go
@@ -2,10 +2,9 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package net
+package poll
 
 import (
-	"os"
 	"runtime"
 	"sync"
 	"syscall"
@@ -49,7 +48,7 @@
 		// Go runtime.
 		runtime.LockOSThread()
 		runtime_ignoreHangup()
-		aio.pid = os.Getpid()
+		aio.pid = syscall.Getpid()
 		aio.mu.Unlock()
 
 		n, err := fn(b)
@@ -64,8 +63,6 @@
 	return aio
 }
 
-var hangupNote os.Signal = syscall.Note("hangup")
-
 // Cancel interrupts the I/O operation, causing
 // the Wait function to return.
 func (aio *asyncIO) Cancel() {
@@ -74,11 +71,12 @@
 	if aio.pid == -1 {
 		return
 	}
-	proc, err := os.FindProcess(aio.pid)
-	if err != nil {
+	f, e := syscall.Open("/proc/"+itoa(aio.pid)+"/note", syscall.O_WRONLY)
+	if e != nil {
 		return
 	}
-	proc.Signal(hangupNote)
+	syscall.Write(f, []byte("hangup"))
+	syscall.Close(f)
 }
 
 // Wait for the I/O operation to complete.
diff --git a/libgo/go/net/fd_mutex.go b/libgo/go/internal/poll/fd_mutex.go
similarity index 89%
rename from libgo/go/net/fd_mutex.go
rename to libgo/go/internal/poll/fd_mutex.go
index 4591fd1..76174e5 100644
--- a/libgo/go/net/fd_mutex.go
+++ b/libgo/go/internal/poll/fd_mutex.go
@@ -2,13 +2,13 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package net
+package poll
 
 import "sync/atomic"
 
 // fdMutex is a specialized synchronization primitive that manages
 // lifetime of an fd and serializes access to Read, Write and Close
-// methods on netFD.
+// methods on FD.
 type fdMutex struct {
 	state uint64
 	rsema uint32
@@ -16,7 +16,7 @@
 }
 
 // fdMutex.state is organized as follows:
-// 1 bit - whether netFD is closed, if set all subsequent lock operations will fail.
+// 1 bit - whether FD is closed, if set all subsequent lock operations will fail.
 // 1 bit - lock for read operations.
 // 1 bit - lock for write operations.
 // 20 bits - total number of references (read+write+misc).
@@ -56,7 +56,7 @@
 		}
 		new := old + mutexRef
 		if new&mutexRefMask == 0 {
-			panic("net: inconsistent fdMutex")
+			panic("inconsistent poll.fdMutex")
 		}
 		if atomic.CompareAndSwapUint64(&mu.state, old, new) {
 			return true
@@ -75,7 +75,7 @@
 		// Mark as closed and acquire a reference.
 		new := (old | mutexClosed) + mutexRef
 		if new&mutexRefMask == 0 {
-			panic("net: inconsistent fdMutex")
+			panic("inconsistent poll.fdMutex")
 		}
 		// Remove all read and write waiters.
 		new &^= mutexRMask | mutexWMask
@@ -101,7 +101,7 @@
 	for {
 		old := atomic.LoadUint64(&mu.state)
 		if old&mutexRefMask == 0 {
-			panic("net: inconsistent fdMutex")
+			panic("inconsistent poll.fdMutex")
 		}
 		new := old - mutexRef
 		if atomic.CompareAndSwapUint64(&mu.state, old, new) {
@@ -136,13 +136,13 @@
 			// Lock is free, acquire it.
 			new = (old | mutexBit) + mutexRef
 			if new&mutexRefMask == 0 {
-				panic("net: inconsistent fdMutex")
+				panic("inconsistent poll.fdMutex")
 			}
 		} else {
 			// Wait for lock.
 			new = old + mutexWait
 			if new&mutexMask == 0 {
-				panic("net: inconsistent fdMutex")
+				panic("inconsistent poll.fdMutex")
 			}
 		}
 		if atomic.CompareAndSwapUint64(&mu.state, old, new) {
@@ -174,7 +174,7 @@
 	for {
 		old := atomic.LoadUint64(&mu.state)
 		if old&mutexBit == 0 || old&mutexRefMask == 0 {
-			panic("net: inconsistent fdMutex")
+			panic("inconsistent poll.fdMutex")
 		}
 		// Drop lock, drop reference and wake read waiter if present.
 		new := (old &^ mutexBit) - mutexRef
@@ -196,9 +196,9 @@
 
 // incref adds a reference to fd.
 // It returns an error when fd cannot be used.
-func (fd *netFD) incref() error {
+func (fd *FD) incref() error {
 	if !fd.fdmu.incref() {
-		return errClosing
+		return errClosing(fd.isFile)
 	}
 	return nil
 }
@@ -206,17 +206,18 @@
 // decref removes a reference from fd.
 // It also closes fd when the state of fd is set to closed and there
 // is no remaining reference.
-func (fd *netFD) decref() {
+func (fd *FD) decref() error {
 	if fd.fdmu.decref() {
-		fd.destroy()
+		return fd.destroy()
 	}
+	return nil
 }
 
 // readLock adds a reference to fd and locks fd for reading.
 // It returns an error when fd cannot be used for reading.
-func (fd *netFD) readLock() error {
+func (fd *FD) readLock() error {
 	if !fd.fdmu.rwlock(true) {
-		return errClosing
+		return errClosing(fd.isFile)
 	}
 	return nil
 }
@@ -224,7 +225,7 @@
 // readUnlock removes a reference from fd and unlocks fd for reading.
 // It also closes fd when the state of fd is set to closed and there
 // is no remaining reference.
-func (fd *netFD) readUnlock() {
+func (fd *FD) readUnlock() {
 	if fd.fdmu.rwunlock(true) {
 		fd.destroy()
 	}
@@ -232,9 +233,9 @@
 
 // writeLock adds a reference to fd and locks fd for writing.
 // It returns an error when fd cannot be used for writing.
-func (fd *netFD) writeLock() error {
+func (fd *FD) writeLock() error {
 	if !fd.fdmu.rwlock(false) {
-		return errClosing
+		return errClosing(fd.isFile)
 	}
 	return nil
 }
@@ -242,7 +243,7 @@
 // writeUnlock removes a reference from fd and unlocks fd for writing.
 // It also closes fd when the state of fd is set to closed and there
 // is no remaining reference.
-func (fd *netFD) writeUnlock() {
+func (fd *FD) writeUnlock() {
 	if fd.fdmu.rwunlock(false) {
 		fd.destroy()
 	}
diff --git a/libgo/go/net/fd_mutex_test.go b/libgo/go/internal/poll/fd_mutex_test.go
similarity index 67%
rename from libgo/go/net/fd_mutex_test.go
rename to libgo/go/internal/poll/fd_mutex_test.go
index 3542c70..bab81c6 100644
--- a/libgo/go/net/fd_mutex_test.go
+++ b/libgo/go/internal/poll/fd_mutex_test.go
@@ -2,9 +2,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package net
+package poll_test
 
 import (
+	. "internal/poll"
 	"math/rand"
 	"runtime"
 	"testing"
@@ -12,57 +13,57 @@
 )
 
 func TestMutexLock(t *testing.T) {
-	var mu fdMutex
+	var mu FDMutex
 
-	if !mu.incref() {
+	if !mu.Incref() {
 		t.Fatal("broken")
 	}
-	if mu.decref() {
+	if mu.Decref() {
 		t.Fatal("broken")
 	}
 
-	if !mu.rwlock(true) {
+	if !mu.RWLock(true) {
 		t.Fatal("broken")
 	}
-	if mu.rwunlock(true) {
+	if mu.RWUnlock(true) {
 		t.Fatal("broken")
 	}
 
-	if !mu.rwlock(false) {
+	if !mu.RWLock(false) {
 		t.Fatal("broken")
 	}
-	if mu.rwunlock(false) {
+	if mu.RWUnlock(false) {
 		t.Fatal("broken")
 	}
 }
 
 func TestMutexClose(t *testing.T) {
-	var mu fdMutex
-	if !mu.increfAndClose() {
+	var mu FDMutex
+	if !mu.IncrefAndClose() {
 		t.Fatal("broken")
 	}
 
-	if mu.incref() {
+	if mu.Incref() {
 		t.Fatal("broken")
 	}
-	if mu.rwlock(true) {
+	if mu.RWLock(true) {
 		t.Fatal("broken")
 	}
-	if mu.rwlock(false) {
+	if mu.RWLock(false) {
 		t.Fatal("broken")
 	}
-	if mu.increfAndClose() {
+	if mu.IncrefAndClose() {
 		t.Fatal("broken")
 	}
 }
 
 func TestMutexCloseUnblock(t *testing.T) {
 	c := make(chan bool)
-	var mu fdMutex
-	mu.rwlock(true)
+	var mu FDMutex
+	mu.RWLock(true)
 	for i := 0; i < 4; i++ {
 		go func() {
-			if mu.rwlock(true) {
+			if mu.RWLock(true) {
 				t.Error("broken")
 				return
 			}
@@ -76,7 +77,7 @@
 		t.Fatal("broken")
 	default:
 	}
-	mu.increfAndClose() // Must unblock the readers.
+	mu.IncrefAndClose() // Must unblock the readers.
 	for i := 0; i < 4; i++ {
 		select {
 		case <-c:
@@ -84,10 +85,10 @@
 			t.Fatal("broken")
 		}
 	}
-	if mu.decref() {
+	if mu.Decref() {
 		t.Fatal("broken")
 	}
-	if !mu.rwunlock(true) {
+	if !mu.RWUnlock(true) {
 		t.Fatal("broken")
 	}
 }
@@ -102,22 +103,22 @@
 		f()
 	}
 
-	var mu fdMutex
-	ensurePanics(func() { mu.decref() })
-	ensurePanics(func() { mu.rwunlock(true) })
-	ensurePanics(func() { mu.rwunlock(false) })
+	var mu FDMutex
+	ensurePanics(func() { mu.Decref() })
+	ensurePanics(func() { mu.RWUnlock(true) })
+	ensurePanics(func() { mu.RWUnlock(false) })
 
-	ensurePanics(func() { mu.incref(); mu.decref(); mu.decref() })
-	ensurePanics(func() { mu.rwlock(true); mu.rwunlock(true); mu.rwunlock(true) })
-	ensurePanics(func() { mu.rwlock(false); mu.rwunlock(false); mu.rwunlock(false) })
+	ensurePanics(func() { mu.Incref(); mu.Decref(); mu.Decref() })
+	ensurePanics(func() { mu.RWLock(true); mu.RWUnlock(true); mu.RWUnlock(true) })
+	ensurePanics(func() { mu.RWLock(false); mu.RWUnlock(false); mu.RWUnlock(false) })
 
 	// ensure that it's still not broken
-	mu.incref()
-	mu.decref()
-	mu.rwlock(true)
-	mu.rwunlock(true)
-	mu.rwlock(false)
-	mu.rwunlock(false)
+	mu.Incref()
+	mu.Decref()
+	mu.RWLock(true)
+	mu.RWUnlock(true)
+	mu.RWLock(false)
+	mu.RWUnlock(false)
 }
 
 func TestMutexStress(t *testing.T) {
@@ -129,7 +130,7 @@
 	}
 	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(P))
 	done := make(chan bool)
-	var mu fdMutex
+	var mu FDMutex
 	var readState [2]uint64
 	var writeState [2]uint64
 	for p := 0; p < P; p++ {
@@ -138,16 +139,16 @@
 			for i := 0; i < N; i++ {
 				switch r.Intn(3) {
 				case 0:
-					if !mu.incref() {
+					if !mu.Incref() {
 						t.Error("broken")
 						return
 					}
-					if mu.decref() {
+					if mu.Decref() {
 						t.Error("broken")
 						return
 					}
 				case 1:
-					if !mu.rwlock(true) {
+					if !mu.RWLock(true) {
 						t.Error("broken")
 						return
 					}
@@ -158,12 +159,12 @@
 					}
 					readState[0]++
 					readState[1]++
-					if mu.rwunlock(true) {
+					if mu.RWUnlock(true) {
 						t.Error("broken")
 						return
 					}
 				case 2:
-					if !mu.rwlock(false) {
+					if !mu.RWLock(false) {
 						t.Error("broken")
 						return
 					}
@@ -174,7 +175,7 @@
 					}
 					writeState[0]++
 					writeState[1]++
-					if mu.rwunlock(false) {
+					if mu.RWUnlock(false) {
 						t.Error("broken")
 						return
 					}
@@ -186,10 +187,10 @@
 	for p := 0; p < P; p++ {
 		<-done
 	}
-	if !mu.increfAndClose() {
+	if !mu.IncrefAndClose() {
 		t.Fatal("broken")
 	}
-	if !mu.decref() {
+	if !mu.Decref() {
 		t.Fatal("broken")
 	}
 }
diff --git a/libgo/go/internal/poll/fd_plan9.go b/libgo/go/internal/poll/fd_plan9.go
new file mode 100644
index 0000000..107f454
--- /dev/null
+++ b/libgo/go/internal/poll/fd_plan9.go
@@ -0,0 +1,216 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import (
+	"errors"
+	"io"
+	"sync/atomic"
+	"time"
+)
+
+type atomicBool int32
+
+func (b *atomicBool) isSet() bool { return atomic.LoadInt32((*int32)(b)) != 0 }
+func (b *atomicBool) setFalse()   { atomic.StoreInt32((*int32)(b), 0) }
+func (b *atomicBool) setTrue()    { atomic.StoreInt32((*int32)(b), 1) }
+
+type FD struct {
+	// Lock sysfd and serialize access to Read and Write methods.
+	fdmu fdMutex
+
+	Destroy func()
+
+	// deadlines
+	raio      *asyncIO
+	waio      *asyncIO
+	rtimer    *time.Timer
+	wtimer    *time.Timer
+	rtimedout atomicBool // set true when read deadline has been reached
+	wtimedout atomicBool // set true when write deadline has been reached
+
+	// Whether this is a normal file.
+	// On Plan 9 we do not use this package for ordinary files,
+	// so this is always false, but the field is present because
+	// shared code in fd_mutex.go checks it.
+	isFile bool
+}
+
+// We need this to close out a file descriptor when it is unlocked,
+// but the real implementation has to live in the net package because
+// it uses os.File's.
+func (fd *FD) destroy() error {
+	if fd.Destroy != nil {
+		fd.Destroy()
+	}
+	return nil
+}
+
+// Close handles the locking for closing an FD. The real operation
+// is in the net package.
+func (fd *FD) Close() error {
+	if !fd.fdmu.increfAndClose() {
+		return errClosing(fd.isFile)
+	}
+	return nil
+}
+
+// Read implements io.Reader.
+func (fd *FD) Read(fn func([]byte) (int, error), b []byte) (int, error) {
+	if fd.rtimedout.isSet() {
+		return 0, ErrTimeout
+	}
+	if err := fd.readLock(); err != nil {
+		return 0, err
+	}
+	defer fd.readUnlock()
+	if len(b) == 0 {
+		return 0, nil
+	}
+	fd.raio = newAsyncIO(fn, b)
+	n, err := fd.raio.Wait()
+	fd.raio = nil
+	if isHangup(err) {
+		err = io.EOF
+	}
+	if isInterrupted(err) {
+		err = ErrTimeout
+	}
+	return n, err
+}
+
+// Write implements io.Writer.
+func (fd *FD) Write(fn func([]byte) (int, error), b []byte) (int, error) {
+	if fd.wtimedout.isSet() {
+		return 0, ErrTimeout
+	}
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	fd.waio = newAsyncIO(fn, b)
+	n, err := fd.waio.Wait()
+	fd.waio = nil
+	if isInterrupted(err) {
+		err = ErrTimeout
+	}
+	return n, err
+}
+
+// SetDeadline sets the read and write deadlines associated with fd.
+func (fd *FD) SetDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r'+'w')
+}
+
+// SetReadDeadline sets the read deadline associated with fd.
+func (fd *FD) SetReadDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r')
+}
+
+// SetWriteDeadline sets the write deadline associated with fd.
+func (fd *FD) SetWriteDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'w')
+}
+
+func setDeadlineImpl(fd *FD, t time.Time, mode int) error {
+	d := t.Sub(time.Now())
+	if mode == 'r' || mode == 'r'+'w' {
+		fd.rtimedout.setFalse()
+	}
+	if mode == 'w' || mode == 'r'+'w' {
+		fd.wtimedout.setFalse()
+	}
+	if t.IsZero() || d < 0 {
+		// Stop timer
+		if mode == 'r' || mode == 'r'+'w' {
+			if fd.rtimer != nil {
+				fd.rtimer.Stop()
+			}
+			fd.rtimer = nil
+		}
+		if mode == 'w' || mode == 'r'+'w' {
+			if fd.wtimer != nil {
+				fd.wtimer.Stop()
+			}
+			fd.wtimer = nil
+		}
+	} else {
+		// Interrupt I/O operation once timer has expired
+		if mode == 'r' || mode == 'r'+'w' {
+			fd.rtimer = time.AfterFunc(d, func() {
+				fd.rtimedout.setTrue()
+				if fd.raio != nil {
+					fd.raio.Cancel()
+				}
+			})
+		}
+		if mode == 'w' || mode == 'r'+'w' {
+			fd.wtimer = time.AfterFunc(d, func() {
+				fd.wtimedout.setTrue()
+				if fd.waio != nil {
+					fd.waio.Cancel()
+				}
+			})
+		}
+	}
+	if !t.IsZero() && d < 0 {
+		// Interrupt current I/O operation
+		if mode == 'r' || mode == 'r'+'w' {
+			fd.rtimedout.setTrue()
+			if fd.raio != nil {
+				fd.raio.Cancel()
+			}
+		}
+		if mode == 'w' || mode == 'r'+'w' {
+			fd.wtimedout.setTrue()
+			if fd.waio != nil {
+				fd.waio.Cancel()
+			}
+		}
+	}
+	return nil
+}
+
+// On Plan 9 only, expose the locking for the net code.
+
+// ReadLock wraps FD.readLock.
+func (fd *FD) ReadLock() error {
+	return fd.readLock()
+}
+
+// ReadUnlock wraps FD.readUnlock.
+func (fd *FD) ReadUnlock() {
+	fd.readUnlock()
+}
+
+func isHangup(err error) bool {
+	return err != nil && stringsHasSuffix(err.Error(), "Hangup")
+}
+
+func isInterrupted(err error) bool {
+	return err != nil && stringsHasSuffix(err.Error(), "interrupted")
+}
+
+// PollDescriptor returns the descriptor being used by the poller,
+// or ^uintptr(0) if there isn't one. This is only used for testing.
+func PollDescriptor() uintptr {
+	return ^uintptr(0)
+}
+
+// RawControl invokes the user-defined function f for a non-IO
+// operation.
+func (fd *FD) RawControl(f func(uintptr)) error {
+	return errors.New("not implemented")
+}
+
+// RawRead invokes the user-defined function f for a read operation.
+func (fd *FD) RawRead(f func(uintptr) bool) error {
+	return errors.New("not implemented")
+}
+
+// RawWrite invokes the user-defined function f for a write operation.
+func (fd *FD) RawWrite(f func(uintptr) bool) error {
+	return errors.New("not implemented")
+}
diff --git a/libgo/go/internal/poll/fd_poll_nacl.go b/libgo/go/internal/poll/fd_poll_nacl.go
new file mode 100644
index 0000000..2df3003
--- /dev/null
+++ b/libgo/go/internal/poll/fd_poll_nacl.go
@@ -0,0 +1,94 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import (
+	"syscall"
+	"time"
+)
+
+type pollDesc struct {
+	fd      *FD
+	closing bool
+}
+
+func (pd *pollDesc) init(fd *FD) error { pd.fd = fd; return nil }
+
+func (pd *pollDesc) close() {}
+
+func (pd *pollDesc) evict() {
+	pd.closing = true
+	if pd.fd != nil {
+		syscall.StopIO(pd.fd.Sysfd)
+	}
+}
+
+func (pd *pollDesc) prepare(mode int, isFile bool) error {
+	if pd.closing {
+		return errClosing(isFile)
+	}
+	return nil
+}
+
+func (pd *pollDesc) prepareRead(isFile bool) error { return pd.prepare('r', isFile) }
+
+func (pd *pollDesc) prepareWrite(isFile bool) error { return pd.prepare('w', isFile) }
+
+func (pd *pollDesc) wait(mode int, isFile bool) error {
+	if pd.closing {
+		return errClosing(isFile)
+	}
+	return ErrTimeout
+}
+
+func (pd *pollDesc) waitRead(isFile bool) error { return pd.wait('r', isFile) }
+
+func (pd *pollDesc) waitWrite(isFile bool) error { return pd.wait('w', isFile) }
+
+func (pd *pollDesc) waitCanceled(mode int) {}
+
+func (pd *pollDesc) pollable() bool { return true }
+
+// SetDeadline sets the read and write deadlines associated with fd.
+func (fd *FD) SetDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r'+'w')
+}
+
+// SetReadDeadline sets the read deadline associated with fd.
+func (fd *FD) SetReadDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r')
+}
+
+// SetWriteDeadline sets the write deadline associated with fd.
+func (fd *FD) SetWriteDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'w')
+}
+
+func setDeadlineImpl(fd *FD, t time.Time, mode int) error {
+	d := t.UnixNano()
+	if t.IsZero() {
+		d = 0
+	}
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	switch mode {
+	case 'r':
+		syscall.SetReadDeadline(fd.Sysfd, d)
+	case 'w':
+		syscall.SetWriteDeadline(fd.Sysfd, d)
+	case 'r' + 'w':
+		syscall.SetReadDeadline(fd.Sysfd, d)
+		syscall.SetWriteDeadline(fd.Sysfd, d)
+	}
+	fd.decref()
+	return nil
+}
+
+// PollDescriptor returns the descriptor being used by the poller,
+// or ^uintptr(0) if there isn't one. This is only used for testing.
+func PollDescriptor() uintptr {
+	return ^uintptr(0)
+}
diff --git a/libgo/go/internal/poll/fd_poll_runtime.go b/libgo/go/internal/poll/fd_poll_runtime.go
new file mode 100644
index 0000000..bfbe3c7
--- /dev/null
+++ b/libgo/go/internal/poll/fd_poll_runtime.go
@@ -0,0 +1,162 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd windows solaris
+
+package poll
+
+import (
+	"errors"
+	"sync"
+	"syscall"
+	"time"
+)
+
+// runtimeNano returns the current value of the runtime clock in nanoseconds.
+func runtimeNano() int64
+
+func runtime_pollServerInit()
+func runtime_pollServerDescriptor() uintptr
+func runtime_pollOpen(fd uintptr) (uintptr, int)
+func runtime_pollClose(ctx uintptr)
+func runtime_pollWait(ctx uintptr, mode int) int
+func runtime_pollWaitCanceled(ctx uintptr, mode int) int
+func runtime_pollReset(ctx uintptr, mode int) int
+func runtime_pollSetDeadline(ctx uintptr, d int64, mode int)
+func runtime_pollUnblock(ctx uintptr)
+
+type pollDesc struct {
+	runtimeCtx uintptr
+}
+
+var serverInit sync.Once
+
+func (pd *pollDesc) init(fd *FD) error {
+	serverInit.Do(runtime_pollServerInit)
+	ctx, errno := runtime_pollOpen(uintptr(fd.Sysfd))
+	if errno != 0 {
+		if ctx != 0 {
+			runtime_pollUnblock(ctx)
+			runtime_pollClose(ctx)
+		}
+		return syscall.Errno(errno)
+	}
+	pd.runtimeCtx = ctx
+	return nil
+}
+
+func (pd *pollDesc) close() {
+	if pd.runtimeCtx == 0 {
+		return
+	}
+	runtime_pollClose(pd.runtimeCtx)
+	pd.runtimeCtx = 0
+}
+
+// Evict evicts fd from the pending list, unblocking any I/O running on fd.
+func (pd *pollDesc) evict() {
+	if pd.runtimeCtx == 0 {
+		return
+	}
+	runtime_pollUnblock(pd.runtimeCtx)
+}
+
+func (pd *pollDesc) prepare(mode int, isFile bool) error {
+	if pd.runtimeCtx == 0 {
+		return nil
+	}
+	res := runtime_pollReset(pd.runtimeCtx, mode)
+	return convertErr(res, isFile)
+}
+
+func (pd *pollDesc) prepareRead(isFile bool) error {
+	return pd.prepare('r', isFile)
+}
+
+func (pd *pollDesc) prepareWrite(isFile bool) error {
+	return pd.prepare('w', isFile)
+}
+
+func (pd *pollDesc) wait(mode int, isFile bool) error {
+	if pd.runtimeCtx == 0 {
+		return errors.New("waiting for unsupported file type")
+	}
+	res := runtime_pollWait(pd.runtimeCtx, mode)
+	return convertErr(res, isFile)
+}
+
+func (pd *pollDesc) waitRead(isFile bool) error {
+	return pd.wait('r', isFile)
+}
+
+func (pd *pollDesc) waitWrite(isFile bool) error {
+	return pd.wait('w', isFile)
+}
+
+func (pd *pollDesc) waitCanceled(mode int) {
+	if pd.runtimeCtx == 0 {
+		return
+	}
+	runtime_pollWaitCanceled(pd.runtimeCtx, mode)
+}
+
+func (pd *pollDesc) pollable() bool {
+	return pd.runtimeCtx != 0
+}
+
+func convertErr(res int, isFile bool) error {
+	switch res {
+	case 0:
+		return nil
+	case 1:
+		return errClosing(isFile)
+	case 2:
+		return ErrTimeout
+	}
+	println("unreachable: ", res)
+	panic("unreachable")
+}
+
+// SetDeadline sets the read and write deadlines associated with fd.
+func (fd *FD) SetDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r'+'w')
+}
+
+// SetReadDeadline sets the read deadline associated with fd.
+func (fd *FD) SetReadDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r')
+}
+
+// SetWriteDeadline sets the write deadline associated with fd.
+func (fd *FD) SetWriteDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'w')
+}
+
+func setDeadlineImpl(fd *FD, t time.Time, mode int) error {
+	diff := int64(time.Until(t))
+	d := runtimeNano() + diff
+	if d <= 0 && diff > 0 {
+		// If the user has a deadline in the future, but the delay calculation
+		// overflows, then set the deadline to the maximum possible value.
+		d = 1<<63 - 1
+	}
+	if t.IsZero() {
+		d = 0
+	}
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	if fd.pd.runtimeCtx == 0 {
+		return errors.New("file type does not support deadlines")
+	}
+	runtime_pollSetDeadline(fd.pd.runtimeCtx, d, mode)
+	fd.decref()
+	return nil
+}
+
+// PollDescriptor returns the descriptor being used by the poller,
+// or ^uintptr(0) if there isn't one. This is only used for testing.
+func PollDescriptor() uintptr {
+	return runtime_pollServerDescriptor()
+}
diff --git a/libgo/go/internal/poll/fd_posix.go b/libgo/go/internal/poll/fd_posix.go
new file mode 100644
index 0000000..e0e634c
--- /dev/null
+++ b/libgo/go/internal/poll/fd_posix.go
@@ -0,0 +1,57 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
+
+package poll
+
+import (
+	"io"
+	"syscall"
+)
+
+// eofError returns io.EOF when fd is available for reading end of
+// file.
+func (fd *FD) eofError(n int, err error) error {
+	if n == 0 && err == nil && fd.ZeroReadIsEOF {
+		return io.EOF
+	}
+	return err
+}
+
+// Fchmod wraps syscall.Fchmod.
+func (fd *FD) Fchmod(mode uint32) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Fchmod(fd.Sysfd, mode)
+}
+
+// Fchown wraps syscall.Fchown.
+func (fd *FD) Fchown(uid, gid int) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Fchown(fd.Sysfd, uid, gid)
+}
+
+// Ftruncate wraps syscall.Ftruncate.
+func (fd *FD) Ftruncate(size int64) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Ftruncate(fd.Sysfd, size)
+}
+
+// Fsync wraps syscall.Fsync.
+func (fd *FD) Fsync() error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Fsync(fd.Sysfd)
+}
diff --git a/libgo/go/internal/poll/fd_posix_test.go b/libgo/go/internal/poll/fd_posix_test.go
new file mode 100644
index 0000000..cbe015e
--- /dev/null
+++ b/libgo/go/internal/poll/fd_posix_test.go
@@ -0,0 +1,43 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
+
+package poll_test
+
+import (
+	. "internal/poll"
+	"io"
+	"testing"
+)
+
+var eofErrorTests = []struct {
+	n        int
+	err      error
+	fd       *FD
+	expected error
+}{
+	{100, nil, &FD{ZeroReadIsEOF: true}, nil},
+	{100, io.EOF, &FD{ZeroReadIsEOF: true}, io.EOF},
+	{100, ErrNetClosing, &FD{ZeroReadIsEOF: true}, ErrNetClosing},
+	{0, nil, &FD{ZeroReadIsEOF: true}, io.EOF},
+	{0, io.EOF, &FD{ZeroReadIsEOF: true}, io.EOF},
+	{0, ErrNetClosing, &FD{ZeroReadIsEOF: true}, ErrNetClosing},
+
+	{100, nil, &FD{ZeroReadIsEOF: false}, nil},
+	{100, io.EOF, &FD{ZeroReadIsEOF: false}, io.EOF},
+	{100, ErrNetClosing, &FD{ZeroReadIsEOF: false}, ErrNetClosing},
+	{0, nil, &FD{ZeroReadIsEOF: false}, nil},
+	{0, io.EOF, &FD{ZeroReadIsEOF: false}, io.EOF},
+	{0, ErrNetClosing, &FD{ZeroReadIsEOF: false}, ErrNetClosing},
+}
+
+func TestEOFError(t *testing.T) {
+	for _, tt := range eofErrorTests {
+		actual := tt.fd.EOFError(tt.n, tt.err)
+		if actual != tt.expected {
+			t.Errorf("eofError(%v, %v, %v): expected %v, actual %v", tt.n, tt.err, tt.fd.ZeroReadIsEOF, tt.expected, actual)
+		}
+	}
+}
diff --git a/libgo/go/internal/poll/fd_unix.go b/libgo/go/internal/poll/fd_unix.go
new file mode 100644
index 0000000..c40c701
--- /dev/null
+++ b/libgo/go/internal/poll/fd_unix.go
@@ -0,0 +1,452 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+package poll
+
+import (
+	"io"
+	"syscall"
+)
+
+// FD is a file descriptor. The net and os packages use this type as a
+// field of a larger type representing a network connection or OS file.
+type FD struct {
+	// Lock sysfd and serialize access to Read and Write methods.
+	fdmu fdMutex
+
+	// System file descriptor. Immutable until Close.
+	Sysfd int
+
+	// I/O poller.
+	pd pollDesc
+
+	// Writev cache.
+	iovecs *[]syscall.Iovec
+
+	// Whether this is a streaming descriptor, as opposed to a
+	// packet-based descriptor like a UDP socket. Immutable.
+	IsStream bool
+
+	// Whether a zero byte read indicates EOF. This is false for a
+	// message based socket connection.
+	ZeroReadIsEOF bool
+
+	// Whether this is a file rather than a network socket.
+	isFile bool
+}
+
+// Init initializes the FD. The Sysfd field should already be set.
+// This can be called multiple times on a single FD.
+// The net argument is a network name from the net package (e.g., "tcp"),
+// or "file".
+func (fd *FD) Init(net string, pollable bool) error {
+	// We don't actually care about the various network types.
+	if net == "file" {
+		fd.isFile = true
+	}
+	if !pollable {
+		return nil
+	}
+	return fd.pd.init(fd)
+}
+
+// Destroy closes the file descriptor. This is called when there are
+// no remaining references.
+func (fd *FD) destroy() error {
+	// Poller may want to unregister fd in readiness notification mechanism,
+	// so this must be executed before CloseFunc.
+	fd.pd.close()
+	err := CloseFunc(fd.Sysfd)
+	fd.Sysfd = -1
+	return err
+}
+
+// Close closes the FD. The underlying file descriptor is closed by the
+// destroy method when there are no remaining references.
+func (fd *FD) Close() error {
+	if !fd.fdmu.increfAndClose() {
+		return errClosing(fd.isFile)
+	}
+	// Unblock any I/O.  Once it all unblocks and returns,
+	// so that it cannot be referring to fd.sysfd anymore,
+	// the final decref will close fd.sysfd. This should happen
+	// fairly quickly, since all the I/O is non-blocking, and any
+	// attempts to block in the pollDesc will return errClosing(fd.isFile).
+	fd.pd.evict()
+	// The call to decref will call destroy if there are no other
+	// references.
+	return fd.decref()
+}
+
+// Shutdown wraps the shutdown network call.
+func (fd *FD) Shutdown(how int) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Shutdown(fd.Sysfd, how)
+}
+
+// Darwin and FreeBSD can't read or write 2GB+ files at a time,
+// even on 64-bit systems.
+// The same is true of socket implementations on many systems.
+// See golang.org/issue/7812 and golang.org/issue/16266.
+// Use 1GB instead of, say, 2GB-1, to keep subsequent reads aligned.
+const maxRW = 1 << 30
+
+// Read implements io.Reader.
+func (fd *FD) Read(p []byte) (int, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, err
+	}
+	defer fd.readUnlock()
+	if len(p) == 0 {
+		// If the caller wanted a zero byte read, return immediately
+		// without trying (but after acquiring the readLock).
+		// Otherwise syscall.Read returns 0, nil which looks like
+		// io.EOF.
+		// TODO(bradfitz): make it wait for readability? (Issue 15735)
+		return 0, nil
+	}
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, err
+	}
+	if fd.IsStream && len(p) > maxRW {
+		p = p[:maxRW]
+	}
+	for {
+		n, err := syscall.Read(fd.Sysfd, p)
+		if err != nil {
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, err
+	}
+}
+
+// Pread wraps the pread system call.
+func (fd *FD) Pread(p []byte, off int64) (int, error) {
+	// Call incref, not readLock, because since pread specifies the
+	// offset it is independent from other reads.
+	// Similarly, using the poller doesn't make sense for pread.
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	if fd.IsStream && len(p) > maxRW {
+		p = p[:maxRW]
+	}
+	n, err := syscall.Pread(fd.Sysfd, p, off)
+	if err != nil {
+		n = 0
+	}
+	fd.decref()
+	err = fd.eofError(n, err)
+	return n, err
+}
+
+// ReadFrom wraps the recvfrom network call.
+func (fd *FD) ReadFrom(p []byte) (int, syscall.Sockaddr, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, nil, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, nil, err
+	}
+	for {
+		n, sa, err := syscall.Recvfrom(fd.Sysfd, p, 0)
+		if err != nil {
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, sa, err
+	}
+}
+
+// ReadMsg wraps the recvmsg network call.
+func (fd *FD) ReadMsg(p []byte, oob []byte) (int, int, int, syscall.Sockaddr, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, 0, 0, nil, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, 0, 0, nil, err
+	}
+	for {
+		n, oobn, flags, sa, err := syscall.Recvmsg(fd.Sysfd, p, oob, 0)
+		if err != nil {
+			// TODO(dfc) should n and oobn be set to 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, oobn, flags, sa, err
+	}
+}
+
+// Write implements io.Writer.
+func (fd *FD) Write(p []byte) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, err
+	}
+	var nn int
+	for {
+		max := len(p)
+		if fd.IsStream && max-nn > maxRW {
+			max = nn + maxRW
+		}
+		n, err := syscall.Write(fd.Sysfd, p[nn:max])
+		if n > 0 {
+			nn += n
+		}
+		if nn == len(p) {
+			return nn, err
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return nn, err
+		}
+		if n == 0 {
+			return nn, io.ErrUnexpectedEOF
+		}
+	}
+}
+
+// Pwrite wraps the pwrite system call.
+func (fd *FD) Pwrite(p []byte, off int64) (int, error) {
+	// Call incref, not writeLock, because since pwrite specifies the
+	// offset it is independent from other writes.
+	// Similarly, using the poller doesn't make sense for pwrite.
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+	var nn int
+	for {
+		max := len(p)
+		if fd.IsStream && max-nn > maxRW {
+			max = nn + maxRW
+		}
+		n, err := syscall.Pwrite(fd.Sysfd, p[nn:max], off+int64(nn))
+		if n > 0 {
+			nn += n
+		}
+		if nn == len(p) {
+			return nn, err
+		}
+		if err != nil {
+			return nn, err
+		}
+		if n == 0 {
+			return nn, io.ErrUnexpectedEOF
+		}
+	}
+}
+
+// WriteTo wraps the sendto network call.
+func (fd *FD) WriteTo(p []byte, sa syscall.Sockaddr) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, err
+	}
+	for {
+		err := syscall.Sendto(fd.Sysfd, p, 0, sa)
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return 0, err
+		}
+		return len(p), nil
+	}
+}
+
+// WriteMsg wraps the sendmsg network call.
+func (fd *FD) WriteMsg(p []byte, oob []byte, sa syscall.Sockaddr) (int, int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, 0, err
+	}
+	for {
+		n, err := syscall.SendmsgN(fd.Sysfd, p, oob, sa, 0)
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return n, 0, err
+		}
+		return n, len(oob), err
+	}
+}
+
+// Accept wraps the accept network call.
+func (fd *FD) Accept() (int, syscall.Sockaddr, string, error) {
+	if err := fd.readLock(); err != nil {
+		return -1, nil, "", err
+	}
+	defer fd.readUnlock()
+
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return -1, nil, "", err
+	}
+	for {
+		s, rsa, errcall, err := accept(fd.Sysfd)
+		if err == nil {
+			return s, rsa, "", err
+		}
+		switch err {
+		case syscall.EAGAIN:
+			if fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		case syscall.ECONNABORTED:
+			// This means that a socket on the listen
+			// queue was closed before we Accept()ed it;
+			// it's a silly error, so try again.
+			continue
+		}
+		return -1, nil, errcall, err
+	}
+}
+
+// Seek wraps syscall.Seek.
+func (fd *FD) Seek(offset int64, whence int) (int64, error) {
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+	return syscall.Seek(fd.Sysfd, offset, whence)
+}
+
+// ReadDirent wraps syscall.ReadDirent.
+// We treat this like an ordinary system call rather than a call
+// that tries to fill the buffer.
+func (fd *FD) ReadDirent(buf []byte) (int, error) {
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+	for {
+		n, err := syscall.ReadDirent(fd.Sysfd, buf)
+		if err != nil {
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		// Do not call eofError; caller does not expect to see io.EOF.
+		return n, err
+	}
+}
+
+// Fchdir wraps syscall.Fchdir.
+func (fd *FD) Fchdir() error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Fchdir(fd.Sysfd)
+}
+
+// Fstat wraps syscall.Fstat
+func (fd *FD) Fstat(s *syscall.Stat_t) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Fstat(fd.Sysfd, s)
+}
+
+// On Unix variants only, expose the IO event for the net code.
+
+// WaitWrite waits until data can be read from fd.
+func (fd *FD) WaitWrite() error {
+	return fd.pd.waitWrite(fd.isFile)
+}
+
+// RawControl invokes the user-defined function f for a non-IO
+// operation.
+func (fd *FD) RawControl(f func(uintptr)) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	f(uintptr(fd.Sysfd))
+	return nil
+}
+
+// RawRead invokes the user-defined function f for a read operation.
+func (fd *FD) RawRead(f func(uintptr) bool) error {
+	if err := fd.readLock(); err != nil {
+		return err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return err
+	}
+	for {
+		if f(uintptr(fd.Sysfd)) {
+			return nil
+		}
+		if err := fd.pd.waitRead(fd.isFile); err != nil {
+			return err
+		}
+	}
+}
+
+// RawWrite invokes the user-defined function f for a write operation.
+func (fd *FD) RawWrite(f func(uintptr) bool) error {
+	if err := fd.writeLock(); err != nil {
+		return err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return err
+	}
+	for {
+		if f(uintptr(fd.Sysfd)) {
+			return nil
+		}
+		if err := fd.pd.waitWrite(fd.isFile); err != nil {
+			return err
+		}
+	}
+}
diff --git a/libgo/go/internal/poll/fd_windows.go b/libgo/go/internal/poll/fd_windows.go
new file mode 100644
index 0000000..655f934
--- /dev/null
+++ b/libgo/go/internal/poll/fd_windows.go
@@ -0,0 +1,873 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import (
+	"errors"
+	"internal/race"
+	"io"
+	"runtime"
+	"sync"
+	"syscall"
+	"unicode/utf16"
+	"unicode/utf8"
+	"unsafe"
+)
+
+var (
+	initErr error
+	ioSync  uint64
+)
+
+// CancelIo Windows API cancels all outstanding IO for a particular
+// socket on current thread. To overcome that limitation, we run
+// special goroutine, locked to OS single thread, that both starts
+// and cancels IO. It means, there are 2 unavoidable thread switches
+// for every IO.
+// Some newer versions of Windows has new CancelIoEx API, that does
+// not have that limitation and can be used from any thread. This
+// package uses CancelIoEx API, if present, otherwise it fallback
+// to CancelIo.
+
+var (
+	canCancelIO                               bool // determines if CancelIoEx API is present
+	skipSyncNotif                             bool
+	hasLoadSetFileCompletionNotificationModes bool
+)
+
+func init() {
+	var d syscall.WSAData
+	e := syscall.WSAStartup(uint32(0x202), &d)
+	if e != nil {
+		initErr = e
+	}
+	canCancelIO = syscall.LoadCancelIoEx() == nil
+	hasLoadSetFileCompletionNotificationModes = syscall.LoadSetFileCompletionNotificationModes() == nil
+	if hasLoadSetFileCompletionNotificationModes {
+		// It's not safe to use FILE_SKIP_COMPLETION_PORT_ON_SUCCESS if non IFS providers are installed:
+		// http://support.microsoft.com/kb/2568167
+		skipSyncNotif = true
+		protos := [2]int32{syscall.IPPROTO_TCP, 0}
+		var buf [32]syscall.WSAProtocolInfo
+		len := uint32(unsafe.Sizeof(buf))
+		n, err := syscall.WSAEnumProtocols(&protos[0], &buf[0], &len)
+		if err != nil {
+			skipSyncNotif = false
+		} else {
+			for i := int32(0); i < n; i++ {
+				if buf[i].ServiceFlags1&syscall.XP1_IFS_HANDLES == 0 {
+					skipSyncNotif = false
+					break
+				}
+			}
+		}
+	}
+}
+
+// operation contains superset of data necessary to perform all async IO.
+type operation struct {
+	// Used by IOCP interface, it must be first field
+	// of the struct, as our code rely on it.
+	o syscall.Overlapped
+
+	// fields used by runtime.netpoll
+	runtimeCtx uintptr
+	mode       int32
+	errno      int32
+	qty        uint32
+
+	// fields used only by net package
+	fd     *FD
+	errc   chan error
+	buf    syscall.WSABuf
+	sa     syscall.Sockaddr
+	rsa    *syscall.RawSockaddrAny
+	rsan   int32
+	handle syscall.Handle
+	flags  uint32
+	bufs   []syscall.WSABuf
+}
+
+func (o *operation) InitBuf(buf []byte) {
+	o.buf.Len = uint32(len(buf))
+	o.buf.Buf = nil
+	if len(buf) != 0 {
+		o.buf.Buf = &buf[0]
+	}
+}
+
+func (o *operation) InitBufs(buf *[][]byte) {
+	if o.bufs == nil {
+		o.bufs = make([]syscall.WSABuf, 0, len(*buf))
+	} else {
+		o.bufs = o.bufs[:0]
+	}
+	for _, b := range *buf {
+		var p *byte
+		if len(b) > 0 {
+			p = &b[0]
+		}
+		o.bufs = append(o.bufs, syscall.WSABuf{Len: uint32(len(b)), Buf: p})
+	}
+}
+
+// ClearBufs clears all pointers to Buffers parameter captured
+// by InitBufs, so it can be released by garbage collector.
+func (o *operation) ClearBufs() {
+	for i := range o.bufs {
+		o.bufs[i].Buf = nil
+	}
+	o.bufs = o.bufs[:0]
+}
+
+// ioSrv executes net IO requests.
+type ioSrv struct {
+	req chan ioSrvReq
+}
+
+type ioSrvReq struct {
+	o      *operation
+	submit func(o *operation) error // if nil, cancel the operation
+}
+
+// ProcessRemoteIO will execute submit IO requests on behalf
+// of other goroutines, all on a single os thread, so it can
+// cancel them later. Results of all operations will be sent
+// back to their requesters via channel supplied in request.
+// It is used only when the CancelIoEx API is unavailable.
+func (s *ioSrv) ProcessRemoteIO() {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+	for r := range s.req {
+		if r.submit != nil {
+			r.o.errc <- r.submit(r.o)
+		} else {
+			r.o.errc <- syscall.CancelIo(r.o.fd.Sysfd)
+		}
+	}
+}
+
+// ExecIO executes a single IO operation o. It submits and cancels
+// IO in the current thread for systems where Windows CancelIoEx API
+// is available. Alternatively, it passes the request onto
+// runtime netpoll and waits for completion or cancels request.
+func (s *ioSrv) ExecIO(o *operation, submit func(o *operation) error) (int, error) {
+	if o.fd.pd.runtimeCtx == 0 {
+		return 0, errors.New("internal error: polling on unsupported descriptor type")
+	}
+
+	if !canCancelIO {
+		onceStartServer.Do(startServer)
+	}
+
+	fd := o.fd
+	// Notify runtime netpoll about starting IO.
+	err := fd.pd.prepare(int(o.mode), fd.isFile)
+	if err != nil {
+		return 0, err
+	}
+	// Start IO.
+	if canCancelIO {
+		err = submit(o)
+	} else {
+		// Send request to a special dedicated thread,
+		// so it can stop the IO with CancelIO later.
+		s.req <- ioSrvReq{o, submit}
+		err = <-o.errc
+	}
+	switch err {
+	case nil:
+		// IO completed immediately
+		if o.fd.skipSyncNotif {
+			// No completion message will follow, so return immediately.
+			return int(o.qty), nil
+		}
+		// Need to get our completion message anyway.
+	case syscall.ERROR_IO_PENDING:
+		// IO started, and we have to wait for its completion.
+		err = nil
+	default:
+		return 0, err
+	}
+	// Wait for our request to complete.
+	err = fd.pd.wait(int(o.mode), fd.isFile)
+	if err == nil {
+		// All is good. Extract our IO results and return.
+		if o.errno != 0 {
+			err = syscall.Errno(o.errno)
+			return 0, err
+		}
+		return int(o.qty), nil
+	}
+	// IO is interrupted by "close" or "timeout"
+	netpollErr := err
+	switch netpollErr {
+	case ErrNetClosing, ErrFileClosing, ErrTimeout:
+		// will deal with those.
+	default:
+		panic("unexpected runtime.netpoll error: " + netpollErr.Error())
+	}
+	// Cancel our request.
+	if canCancelIO {
+		err := syscall.CancelIoEx(fd.Sysfd, &o.o)
+		// Assuming ERROR_NOT_FOUND is returned, if IO is completed.
+		if err != nil && err != syscall.ERROR_NOT_FOUND {
+			// TODO(brainman): maybe do something else, but panic.
+			panic(err)
+		}
+	} else {
+		s.req <- ioSrvReq{o, nil}
+		<-o.errc
+	}
+	// Wait for cancelation to complete.
+	fd.pd.waitCanceled(int(o.mode))
+	if o.errno != 0 {
+		err = syscall.Errno(o.errno)
+		if err == syscall.ERROR_OPERATION_ABORTED { // IO Canceled
+			err = netpollErr
+		}
+		return 0, err
+	}
+	// We issued a cancelation request. But, it seems, IO operation succeeded
+	// before the cancelation request run. We need to treat the IO operation as
+	// succeeded (the bytes are actually sent/recv from network).
+	return int(o.qty), nil
+}
+
+// Start helper goroutines.
+var rsrv, wsrv ioSrv
+var onceStartServer sync.Once
+
+func startServer() {
+	// This is called, once, when only the CancelIo API is available.
+	// Start two special goroutines, both locked to an OS thread,
+	// that start and cancel IO requests.
+	// One will process read requests, while the other will do writes.
+	rsrv.req = make(chan ioSrvReq)
+	go rsrv.ProcessRemoteIO()
+	wsrv.req = make(chan ioSrvReq)
+	go wsrv.ProcessRemoteIO()
+}
+
+// FD is a file descriptor. The net and os packages embed this type in
+// a larger type representing a network connection or OS file.
+type FD struct {
+	// Lock sysfd and serialize access to Read and Write methods.
+	fdmu fdMutex
+
+	// System file descriptor. Immutable until Close.
+	Sysfd syscall.Handle
+
+	// Read operation.
+	rop operation
+	// Write operation.
+	wop operation
+
+	// I/O poller.
+	pd pollDesc
+
+	// Used to implement pread/pwrite.
+	l sync.Mutex
+
+	// For console I/O.
+	isConsole      bool
+	lastbits       []byte   // first few bytes of the last incomplete rune in last write
+	readuint16     []uint16 // buffer to hold uint16s obtained with ReadConsole
+	readbyte       []byte   // buffer to hold decoding of readuint16 from utf16 to utf8
+	readbyteOffset int      // readbyte[readOffset:] is yet to be consumed with file.Read
+
+	skipSyncNotif bool
+
+	// Whether this is a streaming descriptor, as opposed to a
+	// packet-based descriptor like a UDP socket.
+	IsStream bool
+
+	// Whether a zero byte read indicates EOF. This is false for a
+	// message based socket connection.
+	ZeroReadIsEOF bool
+
+	// Whether this is a normal file.
+	isFile bool
+
+	// Whether this is a directory.
+	isDir bool
+}
+
+// Init initializes the FD. The Sysfd field should already be set.
+// This can be called multiple times on a single FD.
+// The net argument is a network name from the net package (e.g., "tcp"),
+// or "file" or "console" or "dir".
+func (fd *FD) Init(net string) (string, error) {
+	if initErr != nil {
+		return "", initErr
+	}
+
+	switch net {
+	case "file":
+		fd.isFile = true
+	case "console":
+		fd.isConsole = true
+	case "dir":
+		fd.isDir = true
+	case "tcp", "tcp4", "tcp6":
+	case "udp", "udp4", "udp6":
+	case "ip", "ip4", "ip6":
+	case "unix", "unixgram", "unixpacket":
+	default:
+		return "", errors.New("internal error: unknown network type " + net)
+	}
+
+	if !fd.isFile && !fd.isConsole && !fd.isDir {
+		// Only call init for a network socket.
+		// This means that we don't add files to the runtime poller.
+		// Adding files to the runtime poller can confuse matters
+		// if the user is doing their own overlapped I/O.
+		// See issue #21172.
+		//
+		// In general the code below avoids calling the ExecIO
+		// method for non-network sockets. If some method does
+		// somehow call ExecIO, then ExecIO, and therefore the
+		// calling method, will return an error, because
+		// fd.pd.runtimeCtx will be 0.
+		if err := fd.pd.init(fd); err != nil {
+			return "", err
+		}
+	}
+	if hasLoadSetFileCompletionNotificationModes {
+		// We do not use events, so we can skip them always.
+		flags := uint8(syscall.FILE_SKIP_SET_EVENT_ON_HANDLE)
+		// It's not safe to skip completion notifications for UDP:
+		// http://blogs.technet.com/b/winserverperformance/archive/2008/06/26/designing-applications-for-high-performance-part-iii.aspx
+		if skipSyncNotif && (net == "tcp" || net == "file") {
+			flags |= syscall.FILE_SKIP_COMPLETION_PORT_ON_SUCCESS
+		}
+		err := syscall.SetFileCompletionNotificationModes(fd.Sysfd, flags)
+		if err == nil && flags&syscall.FILE_SKIP_COMPLETION_PORT_ON_SUCCESS != 0 {
+			fd.skipSyncNotif = true
+		}
+	}
+	// Disable SIO_UDP_CONNRESET behavior.
+	// http://support.microsoft.com/kb/263823
+	switch net {
+	case "udp", "udp4", "udp6":
+		ret := uint32(0)
+		flag := uint32(0)
+		size := uint32(unsafe.Sizeof(flag))
+		err := syscall.WSAIoctl(fd.Sysfd, syscall.SIO_UDP_CONNRESET, (*byte)(unsafe.Pointer(&flag)), size, nil, 0, &ret, nil, 0)
+		if err != nil {
+			return "wsaioctl", err
+		}
+	}
+	fd.rop.mode = 'r'
+	fd.wop.mode = 'w'
+	fd.rop.fd = fd
+	fd.wop.fd = fd
+	fd.rop.runtimeCtx = fd.pd.runtimeCtx
+	fd.wop.runtimeCtx = fd.pd.runtimeCtx
+	if !canCancelIO {
+		fd.rop.errc = make(chan error)
+		fd.wop.errc = make(chan error)
+	}
+	return "", nil
+}
+
+func (fd *FD) destroy() error {
+	if fd.Sysfd == syscall.InvalidHandle {
+		return syscall.EINVAL
+	}
+	// Poller may want to unregister fd in readiness notification mechanism,
+	// so this must be executed before fd.CloseFunc.
+	fd.pd.close()
+	var err error
+	if fd.isFile || fd.isConsole {
+		err = syscall.CloseHandle(fd.Sysfd)
+	} else if fd.isDir {
+		err = syscall.FindClose(fd.Sysfd)
+	} else {
+		// The net package uses the CloseFunc variable for testing.
+		err = CloseFunc(fd.Sysfd)
+	}
+	fd.Sysfd = syscall.InvalidHandle
+	return err
+}
+
+// Close closes the FD. The underlying file descriptor is closed by
+// the destroy method when there are no remaining references.
+func (fd *FD) Close() error {
+	if !fd.fdmu.increfAndClose() {
+		return errClosing(fd.isFile)
+	}
+	// unblock pending reader and writer
+	fd.pd.evict()
+	return fd.decref()
+}
+
+// Shutdown wraps the shutdown network call.
+func (fd *FD) Shutdown(how int) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Shutdown(fd.Sysfd, how)
+}
+
+// Read implements io.Reader.
+func (fd *FD) Read(buf []byte) (int, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, err
+	}
+	defer fd.readUnlock()
+
+	var n int
+	var err error
+	if fd.isFile || fd.isDir || fd.isConsole {
+		fd.l.Lock()
+		defer fd.l.Unlock()
+		if fd.isConsole {
+			n, err = fd.readConsole(buf)
+		} else {
+			n, err = syscall.Read(fd.Sysfd, buf)
+		}
+		if err != nil {
+			n = 0
+		}
+	} else {
+		o := &fd.rop
+		o.InitBuf(buf)
+		n, err = rsrv.ExecIO(o, func(o *operation) error {
+			return syscall.WSARecv(o.fd.Sysfd, &o.buf, 1, &o.qty, &o.flags, &o.o, nil)
+		})
+		if race.Enabled {
+			race.Acquire(unsafe.Pointer(&ioSync))
+		}
+	}
+	if len(buf) != 0 {
+		err = fd.eofError(n, err)
+	}
+	return n, err
+}
+
+var ReadConsole = syscall.ReadConsole // changed for testing
+
+// readConsole reads utf16 characters from console File,
+// encodes them into utf8 and stores them in buffer b.
+// It returns the number of utf8 bytes read and an error, if any.
+func (fd *FD) readConsole(b []byte) (int, error) {
+	if len(b) == 0 {
+		return 0, nil
+	}
+
+	if fd.readuint16 == nil {
+		// Note: syscall.ReadConsole fails for very large buffers.
+		// The limit is somewhere around (but not exactly) 16384.
+		// Stay well below.
+		fd.readuint16 = make([]uint16, 0, 10000)
+		fd.readbyte = make([]byte, 0, 4*cap(fd.readuint16))
+	}
+
+	for fd.readbyteOffset >= len(fd.readbyte) {
+		n := cap(fd.readuint16) - len(fd.readuint16)
+		if n > len(b) {
+			n = len(b)
+		}
+		var nw uint32
+		err := ReadConsole(fd.Sysfd, &fd.readuint16[:len(fd.readuint16)+1][len(fd.readuint16)], uint32(n), &nw, nil)
+		if err != nil {
+			return 0, err
+		}
+		uint16s := fd.readuint16[:len(fd.readuint16)+int(nw)]
+		fd.readuint16 = fd.readuint16[:0]
+		buf := fd.readbyte[:0]
+		for i := 0; i < len(uint16s); i++ {
+			r := rune(uint16s[i])
+			if utf16.IsSurrogate(r) {
+				if i+1 == len(uint16s) {
+					if nw > 0 {
+						// Save half surrogate pair for next time.
+						fd.readuint16 = fd.readuint16[:1]
+						fd.readuint16[0] = uint16(r)
+						break
+					}
+					r = utf8.RuneError
+				} else {
+					r = utf16.DecodeRune(r, rune(uint16s[i+1]))
+					if r != utf8.RuneError {
+						i++
+					}
+				}
+			}
+			n := utf8.EncodeRune(buf[len(buf):cap(buf)], r)
+			buf = buf[:len(buf)+n]
+		}
+		fd.readbyte = buf
+		fd.readbyteOffset = 0
+		if nw == 0 {
+			break
+		}
+	}
+
+	src := fd.readbyte[fd.readbyteOffset:]
+	var i int
+	for i = 0; i < len(src) && i < len(b); i++ {
+		x := src[i]
+		if x == 0x1A { // Ctrl-Z
+			if i == 0 {
+				fd.readbyteOffset++
+			}
+			break
+		}
+		b[i] = x
+	}
+	fd.readbyteOffset += i
+	return i, nil
+}
+
+// Pread emulates the Unix pread system call.
+func (fd *FD) Pread(b []byte, off int64) (int, error) {
+	// Call incref, not readLock, because since pread specifies the
+	// offset it is independent from other reads.
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+
+	fd.l.Lock()
+	defer fd.l.Unlock()
+	curoffset, e := syscall.Seek(fd.Sysfd, 0, io.SeekCurrent)
+	if e != nil {
+		return 0, e
+	}
+	defer syscall.Seek(fd.Sysfd, curoffset, io.SeekStart)
+	o := syscall.Overlapped{
+		OffsetHigh: uint32(off >> 32),
+		Offset:     uint32(off),
+	}
+	var done uint32
+	e = syscall.ReadFile(fd.Sysfd, b, &done, &o)
+	if e != nil {
+		done = 0
+		if e == syscall.ERROR_HANDLE_EOF {
+			e = io.EOF
+		}
+	}
+	if len(b) != 0 {
+		e = fd.eofError(int(done), e)
+	}
+	return int(done), e
+}
+
+// ReadFrom wraps the recvfrom network call.
+func (fd *FD) ReadFrom(buf []byte) (int, syscall.Sockaddr, error) {
+	if len(buf) == 0 {
+		return 0, nil, nil
+	}
+	if err := fd.readLock(); err != nil {
+		return 0, nil, err
+	}
+	defer fd.readUnlock()
+	o := &fd.rop
+	o.InitBuf(buf)
+	n, err := rsrv.ExecIO(o, func(o *operation) error {
+		if o.rsa == nil {
+			o.rsa = new(syscall.RawSockaddrAny)
+		}
+		o.rsan = int32(unsafe.Sizeof(*o.rsa))
+		return syscall.WSARecvFrom(o.fd.Sysfd, &o.buf, 1, &o.qty, &o.flags, o.rsa, &o.rsan, &o.o, nil)
+	})
+	err = fd.eofError(n, err)
+	if err != nil {
+		return n, nil, err
+	}
+	sa, _ := o.rsa.Sockaddr()
+	return n, sa, nil
+}
+
+// Write implements io.Writer.
+func (fd *FD) Write(buf []byte) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+
+	var n int
+	var err error
+	if fd.isFile || fd.isDir || fd.isConsole {
+		fd.l.Lock()
+		defer fd.l.Unlock()
+		if fd.isConsole {
+			n, err = fd.writeConsole(buf)
+		} else {
+			n, err = syscall.Write(fd.Sysfd, buf)
+		}
+		if err != nil {
+			n = 0
+		}
+	} else {
+		if race.Enabled {
+			race.ReleaseMerge(unsafe.Pointer(&ioSync))
+		}
+		o := &fd.wop
+		o.InitBuf(buf)
+		n, err = wsrv.ExecIO(o, func(o *operation) error {
+			return syscall.WSASend(o.fd.Sysfd, &o.buf, 1, &o.qty, 0, &o.o, nil)
+		})
+	}
+	return n, err
+}
+
+// writeConsole writes len(b) bytes to the console File.
+// It returns the number of bytes written and an error, if any.
+func (fd *FD) writeConsole(b []byte) (int, error) {
+	n := len(b)
+	runes := make([]rune, 0, 256)
+	if len(fd.lastbits) > 0 {
+		b = append(fd.lastbits, b...)
+		fd.lastbits = nil
+
+	}
+	for len(b) >= utf8.UTFMax || utf8.FullRune(b) {
+		r, l := utf8.DecodeRune(b)
+		runes = append(runes, r)
+		b = b[l:]
+	}
+	if len(b) > 0 {
+		fd.lastbits = make([]byte, len(b))
+		copy(fd.lastbits, b)
+	}
+	// syscall.WriteConsole seems to fail, if given large buffer.
+	// So limit the buffer to 16000 characters. This number was
+	// discovered by experimenting with syscall.WriteConsole.
+	const maxWrite = 16000
+	for len(runes) > 0 {
+		m := len(runes)
+		if m > maxWrite {
+			m = maxWrite
+		}
+		chunk := runes[:m]
+		runes = runes[m:]
+		uint16s := utf16.Encode(chunk)
+		for len(uint16s) > 0 {
+			var written uint32
+			err := syscall.WriteConsole(fd.Sysfd, &uint16s[0], uint32(len(uint16s)), &written, nil)
+			if err != nil {
+				return 0, err
+			}
+			uint16s = uint16s[written:]
+		}
+	}
+	return n, nil
+}
+
+// Pwrite emulates the Unix pwrite system call.
+func (fd *FD) Pwrite(b []byte, off int64) (int, error) {
+	// Call incref, not writeLock, because since pwrite specifies the
+	// offset it is independent from other writes.
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+
+	fd.l.Lock()
+	defer fd.l.Unlock()
+	curoffset, e := syscall.Seek(fd.Sysfd, 0, io.SeekCurrent)
+	if e != nil {
+		return 0, e
+	}
+	defer syscall.Seek(fd.Sysfd, curoffset, io.SeekStart)
+	o := syscall.Overlapped{
+		OffsetHigh: uint32(off >> 32),
+		Offset:     uint32(off),
+	}
+	var done uint32
+	e = syscall.WriteFile(fd.Sysfd, b, &done, &o)
+	if e != nil {
+		return 0, e
+	}
+	return int(done), nil
+}
+
+// Writev emulates the Unix writev system call.
+func (fd *FD) Writev(buf *[][]byte) (int64, error) {
+	if len(*buf) == 0 {
+		return 0, nil
+	}
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if race.Enabled {
+		race.ReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	o := &fd.wop
+	o.InitBufs(buf)
+	n, err := wsrv.ExecIO(o, func(o *operation) error {
+		return syscall.WSASend(o.fd.Sysfd, &o.bufs[0], uint32(len(o.bufs)), &o.qty, 0, &o.o, nil)
+	})
+	o.ClearBufs()
+	TestHookDidWritev(n)
+	consume(buf, int64(n))
+	return int64(n), err
+}
+
+// WriteTo wraps the sendto network call.
+func (fd *FD) WriteTo(buf []byte, sa syscall.Sockaddr) (int, error) {
+	if len(buf) == 0 {
+		return 0, nil
+	}
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	o := &fd.wop
+	o.InitBuf(buf)
+	o.sa = sa
+	n, err := wsrv.ExecIO(o, func(o *operation) error {
+		return syscall.WSASendto(o.fd.Sysfd, &o.buf, 1, &o.qty, 0, o.sa, &o.o, nil)
+	})
+	return n, err
+}
+
+// Call ConnectEx. This doesn't need any locking, since it is only
+// called when the descriptor is first created. This is here rather
+// than in the net package so that it can use fd.wop.
+func (fd *FD) ConnectEx(ra syscall.Sockaddr) error {
+	o := &fd.wop
+	o.sa = ra
+	_, err := wsrv.ExecIO(o, func(o *operation) error {
+		return ConnectExFunc(o.fd.Sysfd, o.sa, nil, 0, nil, &o.o)
+	})
+	return err
+}
+
+func (fd *FD) acceptOne(s syscall.Handle, rawsa []syscall.RawSockaddrAny, o *operation) (string, error) {
+	// Submit accept request.
+	o.handle = s
+	o.rsan = int32(unsafe.Sizeof(rawsa[0]))
+	_, err := rsrv.ExecIO(o, func(o *operation) error {
+		return AcceptFunc(o.fd.Sysfd, o.handle, (*byte)(unsafe.Pointer(&rawsa[0])), 0, uint32(o.rsan), uint32(o.rsan), &o.qty, &o.o)
+	})
+	if err != nil {
+		CloseFunc(s)
+		return "acceptex", err
+	}
+
+	// Inherit properties of the listening socket.
+	err = syscall.Setsockopt(s, syscall.SOL_SOCKET, syscall.SO_UPDATE_ACCEPT_CONTEXT, (*byte)(unsafe.Pointer(&fd.Sysfd)), int32(unsafe.Sizeof(fd.Sysfd)))
+	if err != nil {
+		CloseFunc(s)
+		return "setsockopt", err
+	}
+
+	return "", nil
+}
+
+// Accept handles accepting a socket. The sysSocket parameter is used
+// to allocate the net socket.
+func (fd *FD) Accept(sysSocket func() (syscall.Handle, error)) (syscall.Handle, []syscall.RawSockaddrAny, uint32, string, error) {
+	if err := fd.readLock(); err != nil {
+		return syscall.InvalidHandle, nil, 0, "", err
+	}
+	defer fd.readUnlock()
+
+	o := &fd.rop
+	var rawsa [2]syscall.RawSockaddrAny
+	for {
+		s, err := sysSocket()
+		if err != nil {
+			return syscall.InvalidHandle, nil, 0, "", err
+		}
+
+		errcall, err := fd.acceptOne(s, rawsa[:], o)
+		if err == nil {
+			return s, rawsa[:], uint32(o.rsan), "", nil
+		}
+
+		// Sometimes we see WSAECONNRESET and ERROR_NETNAME_DELETED is
+		// returned here. These happen if connection reset is received
+		// before AcceptEx could complete. These errors relate to new
+		// connection, not to AcceptEx, so ignore broken connection and
+		// try AcceptEx again for more connections.
+		errno, ok := err.(syscall.Errno)
+		if !ok {
+			return syscall.InvalidHandle, nil, 0, errcall, err
+		}
+		switch errno {
+		case syscall.ERROR_NETNAME_DELETED, syscall.WSAECONNRESET:
+			// ignore these and try again
+		default:
+			return syscall.InvalidHandle, nil, 0, errcall, err
+		}
+	}
+}
+
+// Seek wraps syscall.Seek.
+func (fd *FD) Seek(offset int64, whence int) (int64, error) {
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+
+	fd.l.Lock()
+	defer fd.l.Unlock()
+
+	return syscall.Seek(fd.Sysfd, offset, whence)
+}
+
+// FindNextFile wraps syscall.FindNextFile.
+func (fd *FD) FindNextFile(data *syscall.Win32finddata) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.FindNextFile(fd.Sysfd, data)
+}
+
+// Fchdir wraps syscall.Fchdir.
+func (fd *FD) Fchdir() error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Fchdir(fd.Sysfd)
+}
+
+// GetFileType wraps syscall.GetFileType.
+func (fd *FD) GetFileType() (uint32, error) {
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+	return syscall.GetFileType(fd.Sysfd)
+}
+
+// GetFileInformationByHandle wraps GetFileInformationByHandle.
+func (fd *FD) GetFileInformationByHandle(data *syscall.ByHandleFileInformation) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.GetFileInformationByHandle(fd.Sysfd, data)
+}
+
+// RawControl invokes the user-defined function f for a non-IO
+// operation.
+func (fd *FD) RawControl(f func(uintptr)) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	f(uintptr(fd.Sysfd))
+	return nil
+}
+
+// RawRead invokes the user-defined function f for a read operation.
+func (fd *FD) RawRead(f func(uintptr) bool) error {
+	return errors.New("not implemented")
+}
+
+// RawWrite invokes the user-defined function f for a write operation.
+func (fd *FD) RawWrite(f func(uintptr) bool) error {
+	return errors.New("not implemented")
+}
diff --git a/libgo/go/internal/poll/hook_cloexec.go b/libgo/go/internal/poll/hook_cloexec.go
new file mode 100644
index 0000000..73df6ed
--- /dev/null
+++ b/libgo/go/internal/poll/hook_cloexec.go
@@ -0,0 +1,12 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build dragonfly freebsd linux
+
+package poll
+
+import "syscall"
+
+// Accept4Func is used to hook the accept4 call.
+var Accept4Func func(int, int) (int, syscall.Sockaddr, error) = syscall.Accept4
diff --git a/libgo/go/internal/poll/hook_unix.go b/libgo/go/internal/poll/hook_unix.go
new file mode 100644
index 0000000..85e102d
--- /dev/null
+++ b/libgo/go/internal/poll/hook_unix.go
@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+package poll
+
+import "syscall"
+
+// CloseFunc is used to hook the close call.
+var CloseFunc func(int) error = syscall.Close
+
+// AcceptFunc is used to hook the accept call.
+var AcceptFunc func(int) (int, syscall.Sockaddr, error) = syscall.Accept
diff --git a/libgo/go/internal/poll/hook_windows.go b/libgo/go/internal/poll/hook_windows.go
new file mode 100644
index 0000000..0bd950e
--- /dev/null
+++ b/libgo/go/internal/poll/hook_windows.go
@@ -0,0 +1,16 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import "syscall"
+
+// CloseFunc is used to hook the close call.
+var CloseFunc func(syscall.Handle) error = syscall.Closesocket
+
+// AcceptFunc is used to hook the accept call.
+var AcceptFunc func(syscall.Handle, syscall.Handle, *byte, uint32, uint32, uint32, *uint32, *syscall.Overlapped) error = syscall.AcceptEx
+
+// ConnectExFunc is used to hook the ConnectEx call.
+var ConnectExFunc func(syscall.Handle, syscall.Sockaddr, *byte, uint32, *uint32, *syscall.Overlapped) error = syscall.ConnectEx
diff --git a/libgo/go/internal/poll/sendfile_bsd.go b/libgo/go/internal/poll/sendfile_bsd.go
new file mode 100644
index 0000000..980a75a
--- /dev/null
+++ b/libgo/go/internal/poll/sendfile_bsd.go
@@ -0,0 +1,53 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build dragonfly freebsd
+
+package poll
+
+import "syscall"
+
+// maxSendfileSize is the largest chunk size we ask the kernel to copy
+// at a time.
+const maxSendfileSize int = 4 << 20
+
+// SendFile wraps the sendfile system call.
+func SendFile(dstFD *FD, src int, pos, remain int64) (int64, error) {
+	if err := dstFD.writeLock(); err != nil {
+		return 0, err
+	}
+	defer dstFD.writeUnlock()
+	dst := int(dstFD.Sysfd)
+	var written int64
+	var err error
+	for remain > 0 {
+		n := maxSendfileSize
+		if int64(n) > remain {
+			n = int(remain)
+		}
+		pos1 := pos
+		n, err1 := syscall.Sendfile(dst, src, &pos1, n)
+		if n > 0 {
+			pos += int64(n)
+			written += int64(n)
+			remain -= int64(n)
+		}
+		if n == 0 && err1 == nil {
+			break
+		}
+		if err1 == syscall.EAGAIN {
+			if err1 = dstFD.pd.waitWrite(dstFD.isFile); err1 == nil {
+				continue
+			}
+		}
+		if err1 != nil {
+			// This includes syscall.ENOSYS (no kernel
+			// support) and syscall.EINVAL (fd types which
+			// don't implement sendfile)
+			err = err1
+			break
+		}
+	}
+	return written, err
+}
diff --git a/libgo/go/internal/poll/sendfile_linux.go b/libgo/go/internal/poll/sendfile_linux.go
new file mode 100644
index 0000000..52955a1
--- /dev/null
+++ b/libgo/go/internal/poll/sendfile_linux.go
@@ -0,0 +1,50 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import "syscall"
+
+// maxSendfileSize is the largest chunk size we ask the kernel to copy
+// at a time.
+const maxSendfileSize int = 4 << 20
+
+// SendFile wraps the sendfile system call.
+func SendFile(dstFD *FD, src int, remain int64) (int64, error) {
+	if err := dstFD.writeLock(); err != nil {
+		return 0, err
+	}
+	defer dstFD.writeUnlock()
+
+	dst := int(dstFD.Sysfd)
+	var written int64
+	var err error
+	for remain > 0 {
+		n := maxSendfileSize
+		if int64(n) > remain {
+			n = int(remain)
+		}
+		n, err1 := syscall.Sendfile(dst, src, nil, n)
+		if n > 0 {
+			written += int64(n)
+			remain -= int64(n)
+		}
+		if n == 0 && err1 == nil {
+			break
+		}
+		if err1 == syscall.EAGAIN {
+			if err1 = dstFD.pd.waitWrite(dstFD.isFile); err1 == nil {
+				continue
+			}
+		}
+		if err1 != nil {
+			// This includes syscall.ENOSYS (no kernel
+			// support) and syscall.EINVAL (fd types which
+			// don't implement sendfile)
+			err = err1
+			break
+		}
+	}
+	return written, err
+}
diff --git a/libgo/go/internal/poll/sendfile_solaris.go b/libgo/go/internal/poll/sendfile_solaris.go
new file mode 100644
index 0000000..9093d46
--- /dev/null
+++ b/libgo/go/internal/poll/sendfile_solaris.go
@@ -0,0 +1,63 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import "syscall"
+
+// Not strictly needed, but very helpful for debugging, see issue #10221.
+//go:cgo_import_dynamic _ _ "libsendfile.so"
+//go:cgo_import_dynamic _ _ "libsocket.so"
+
+// maxSendfileSize is the largest chunk size we ask the kernel to copy
+// at a time.
+const maxSendfileSize int = 4 << 20
+
+// SendFile wraps the sendfile system call.
+func SendFile(dstFD *FD, src int, pos, remain int64) (int64, error) {
+	if err := dstFD.writeLock(); err != nil {
+		return 0, err
+	}
+	defer dstFD.writeUnlock()
+
+	dst := int(dstFD.Sysfd)
+	var written int64
+	var err error
+	for remain > 0 {
+		n := maxSendfileSize
+		if int64(n) > remain {
+			n = int(remain)
+		}
+		pos1 := pos
+		n, err1 := syscall.Sendfile(dst, src, &pos1, n)
+		if err1 == syscall.EAGAIN || err1 == syscall.EINTR {
+			// partial write may have occurred
+			n = int(pos1 - pos)
+		}
+		if n > 0 {
+			pos += int64(n)
+			written += int64(n)
+			remain -= int64(n)
+		}
+		if n == 0 && err1 == nil {
+			break
+		}
+		if err1 == syscall.EAGAIN {
+			if err1 = dstFD.pd.waitWrite(dstFD.isFile); err1 == nil {
+				continue
+			}
+		}
+		if err1 == syscall.EINTR {
+			continue
+		}
+		if err1 != nil {
+			// This includes syscall.ENOSYS (no kernel
+			// support) and syscall.EINVAL (fd types which
+			// don't implement sendfile)
+			err = err1
+			break
+		}
+	}
+	return written, err
+}
diff --git a/libgo/go/internal/poll/sendfile_windows.go b/libgo/go/internal/poll/sendfile_windows.go
new file mode 100644
index 0000000..c1a2d6d
--- /dev/null
+++ b/libgo/go/internal/poll/sendfile_windows.go
@@ -0,0 +1,23 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import "syscall"
+
+// SendFile wraps the TransmitFile call.
+func SendFile(fd *FD, src syscall.Handle, n int64) (int64, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+
+	o := &fd.wop
+	o.qty = uint32(n)
+	o.handle = src
+	done, err := wsrv.ExecIO(o, func(o *operation) error {
+		return syscall.TransmitFile(o.fd.Sysfd, o.handle, o.qty, 0, &o.o, nil, syscall.TF_WRITE_BEHIND)
+	})
+	return int64(done), err
+}
diff --git a/libgo/go/internal/poll/sock_cloexec.go b/libgo/go/internal/poll/sock_cloexec.go
new file mode 100644
index 0000000..0d5c8bd
--- /dev/null
+++ b/libgo/go/internal/poll/sock_cloexec.go
@@ -0,0 +1,50 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements sysSocket and accept for platforms that
+// provide a fast path for setting SetNonblock and CloseOnExec.
+
+// +build dragonfly freebsd linux
+
+package poll
+
+import "syscall"
+
+// Wrapper around the accept system call that marks the returned file
+// descriptor as nonblocking and close-on-exec.
+func accept(s int) (int, syscall.Sockaddr, string, error) {
+	ns, sa, err := Accept4Func(s, syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC)
+	// On Linux the accept4 system call was introduced in 2.6.28
+	// kernel and on FreeBSD it was introduced in 10 kernel. If we
+	// get an ENOSYS error on both Linux and FreeBSD, or EINVAL
+	// error on Linux, fall back to using accept.
+	switch err {
+	case nil:
+		return ns, sa, "", nil
+	default: // errors other than the ones listed
+		return -1, sa, "accept4", err
+	case syscall.ENOSYS: // syscall missing
+	case syscall.EINVAL: // some Linux use this instead of ENOSYS
+	case syscall.EACCES: // some Linux use this instead of ENOSYS
+	case syscall.EFAULT: // some Linux use this instead of ENOSYS
+	}
+
+	// See ../syscall/exec_unix.go for description of ForkLock.
+	// It is probably okay to hold the lock across syscall.Accept
+	// because we have put fd.sysfd into non-blocking mode.
+	// However, a call to the File method will put it back into
+	// blocking mode. We can't take that risk, so no use of ForkLock here.
+	ns, sa, err = AcceptFunc(s)
+	if err == nil {
+		syscall.CloseOnExec(ns)
+	}
+	if err != nil {
+		return -1, nil, "accept", err
+	}
+	if err = syscall.SetNonblock(ns, true); err != nil {
+		CloseFunc(ns)
+		return -1, nil, "setnonblock", err
+	}
+	return ns, sa, "", nil
+}
diff --git a/libgo/go/internal/poll/sockopt.go b/libgo/go/internal/poll/sockopt.go
new file mode 100644
index 0000000..f86ce70
--- /dev/null
+++ b/libgo/go/internal/poll/sockopt.go
@@ -0,0 +1,36 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris windows
+
+package poll
+
+import "syscall"
+
+// SetsockoptInt wraps the setsockopt network call with an int argument.
+func (fd *FD) SetsockoptInt(level, name, arg int) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptInt(fd.Sysfd, level, name, arg)
+}
+
+// SetsockoptInet4Addr wraps the setsockopt network call with an IPv4 address.
+func (fd *FD) SetsockoptInet4Addr(level, name int, arg [4]byte) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptInet4Addr(fd.Sysfd, level, name, arg)
+}
+
+// SetsockoptLinger wraps the setsockopt network call with a Linger argument.
+func (fd *FD) SetsockoptLinger(level, name int, l *syscall.Linger) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptLinger(fd.Sysfd, level, name, l)
+}
diff --git a/libgo/go/internal/poll/sockopt_linux.go b/libgo/go/internal/poll/sockopt_linux.go
new file mode 100644
index 0000000..bc79c35
--- /dev/null
+++ b/libgo/go/internal/poll/sockopt_linux.go
@@ -0,0 +1,16 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import "syscall"
+
+// SetsockoptIPMreqn wraps the setsockopt network call with an IPMreqn argument.
+func (fd *FD) SetsockoptIPMreqn(level, name int, mreq *syscall.IPMreqn) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptIPMreqn(fd.Sysfd, level, name, mreq)
+}
diff --git a/libgo/go/internal/poll/sockopt_unix.go b/libgo/go/internal/poll/sockopt_unix.go
new file mode 100644
index 0000000..b33644d
--- /dev/null
+++ b/libgo/go/internal/poll/sockopt_unix.go
@@ -0,0 +1,18 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package poll
+
+import "syscall"
+
+// SetsockoptByte wraps the setsockopt network call with a byte argument.
+func (fd *FD) SetsockoptByte(level, name int, arg byte) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptByte(fd.Sysfd, level, name, arg)
+}
diff --git a/libgo/go/internal/poll/sockopt_windows.go b/libgo/go/internal/poll/sockopt_windows.go
new file mode 100644
index 0000000..dd5fb70
--- /dev/null
+++ b/libgo/go/internal/poll/sockopt_windows.go
@@ -0,0 +1,25 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import "syscall"
+
+// Setsockopt wraps the setsockopt network call.
+func (fd *FD) Setsockopt(level, optname int32, optval *byte, optlen int32) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Setsockopt(fd.Sysfd, level, optname, optval, optlen)
+}
+
+// WSAIoctl wraps the WSAIoctl network call.
+func (fd *FD) WSAIoctl(iocc uint32, inbuf *byte, cbif uint32, outbuf *byte, cbob uint32, cbbr *uint32, overlapped *syscall.Overlapped, completionRoutine uintptr) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.WSAIoctl(fd.Sysfd, iocc, inbuf, cbif, outbuf, cbob, cbbr, overlapped, completionRoutine)
+}
diff --git a/libgo/go/internal/poll/sockoptip.go b/libgo/go/internal/poll/sockoptip.go
new file mode 100644
index 0000000..5d5dff6
--- /dev/null
+++ b/libgo/go/internal/poll/sockoptip.go
@@ -0,0 +1,27 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd windows
+
+package poll
+
+import "syscall"
+
+// SetsockoptIPMreq wraps the setsockopt network call with an IPMreq argument.
+func (fd *FD) SetsockoptIPMreq(level, name int, mreq *syscall.IPMreq) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptIPMreq(fd.Sysfd, level, name, mreq)
+}
+
+// SetsockoptIPv6Mreq wraps the setsockopt network call with an IPv6Mreq argument.
+func (fd *FD) SetsockoptIPv6Mreq(level, name int, mreq *syscall.IPv6Mreq) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptIPv6Mreq(fd.Sysfd, level, name, mreq)
+}
diff --git a/libgo/go/internal/poll/strconv.go b/libgo/go/internal/poll/strconv.go
new file mode 100644
index 0000000..21cb40d
--- /dev/null
+++ b/libgo/go/internal/poll/strconv.go
@@ -0,0 +1,41 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build plan9
+
+// Simple conversions to avoid depending on strconv.
+
+package poll
+
+// Convert integer to decimal string
+func itoa(val int) string {
+	if val < 0 {
+		return "-" + uitoa(uint(-val))
+	}
+	return uitoa(uint(val))
+}
+
+// Convert unsigned integer to decimal string
+func uitoa(val uint) string {
+	if val == 0 { // avoid string allocation
+		return "0"
+	}
+	var buf [20]byte // big enough for 64bit value base 10
+	i := len(buf) - 1
+	for val >= 10 {
+		q := val / 10
+		buf[i] = byte('0' + val - q*10)
+		i--
+		val = q
+	}
+	// val < 10
+	buf[i] = byte('0' + val)
+	return string(buf[i:])
+}
+
+// stringsHasSuffix is strings.HasSuffix. It reports whether s ends in
+// suffix.
+func stringsHasSuffix(s, suffix string) bool {
+	return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
+}
diff --git a/libgo/go/internal/poll/sys_cloexec.go b/libgo/go/internal/poll/sys_cloexec.go
new file mode 100644
index 0000000..9ed35bd
--- /dev/null
+++ b/libgo/go/internal/poll/sys_cloexec.go
@@ -0,0 +1,36 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements sysSocket and accept for platforms that do not
+// provide a fast path for setting SetNonblock and CloseOnExec.
+
+// +build darwin nacl netbsd openbsd solaris
+
+package poll
+
+import (
+	"syscall"
+)
+
+// Wrapper around the accept system call that marks the returned file
+// descriptor as nonblocking and close-on-exec.
+func accept(s int) (int, syscall.Sockaddr, string, error) {
+	// See ../syscall/exec_unix.go for description of ForkLock.
+	// It is probably okay to hold the lock across syscall.Accept
+	// because we have put fd.sysfd into non-blocking mode.
+	// However, a call to the File method will put it back into
+	// blocking mode. We can't take that risk, so no use of ForkLock here.
+	ns, sa, err := AcceptFunc(s)
+	if err == nil {
+		syscall.CloseOnExec(ns)
+	}
+	if err != nil {
+		return -1, nil, "accept", err
+	}
+	if err = syscall.SetNonblock(ns, true); err != nil {
+		CloseFunc(ns)
+		return -1, nil, "setnonblock", err
+	}
+	return ns, sa, "", nil
+}
diff --git a/libgo/go/internal/poll/writev.go b/libgo/go/internal/poll/writev.go
new file mode 100644
index 0000000..4bf8804
--- /dev/null
+++ b/libgo/go/internal/poll/writev.go
@@ -0,0 +1,83 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd
+
+package poll
+
+import (
+	"io"
+	"syscall"
+	"unsafe"
+)
+
+// Writev wraps the writev system call.
+func (fd *FD) Writev(v *[][]byte) (int64, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, err
+	}
+
+	var iovecs []syscall.Iovec
+	if fd.iovecs != nil {
+		iovecs = *fd.iovecs
+	}
+	// TODO: read from sysconf(_SC_IOV_MAX)? The Linux default is
+	// 1024 and this seems conservative enough for now. Darwin's
+	// UIO_MAXIOV also seems to be 1024.
+	maxVec := 1024
+
+	var n int64
+	var err error
+	for len(*v) > 0 {
+		iovecs = iovecs[:0]
+		for _, chunk := range *v {
+			if len(chunk) == 0 {
+				continue
+			}
+			iovecs = append(iovecs, syscall.Iovec{Base: &chunk[0]})
+			if fd.IsStream && len(chunk) > 1<<30 {
+				iovecs[len(iovecs)-1].SetLen(1 << 30)
+				break // continue chunk on next writev
+			}
+			iovecs[len(iovecs)-1].SetLen(len(chunk))
+			if len(iovecs) == maxVec {
+				break
+			}
+		}
+		if len(iovecs) == 0 {
+			break
+		}
+		fd.iovecs = &iovecs // cache
+
+		wrote, _, e0 := syscall.Syscall(syscall.SYS_WRITEV,
+			uintptr(fd.Sysfd),
+			uintptr(unsafe.Pointer(&iovecs[0])),
+			uintptr(len(iovecs)))
+		if wrote == ^uintptr(0) {
+			wrote = 0
+		}
+		TestHookDidWritev(int(wrote))
+		n += int64(wrote)
+		consume(v, int64(wrote))
+		if e0 == syscall.EAGAIN {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		} else if e0 != 0 {
+			err = syscall.Errno(e0)
+		}
+		if err != nil {
+			break
+		}
+		if n == 0 {
+			err = io.ErrUnexpectedEOF
+			break
+		}
+	}
+	return n, err
+}
diff --git a/libgo/go/internal/poll/writev_test.go b/libgo/go/internal/poll/writev_test.go
new file mode 100644
index 0000000..b46657c
--- /dev/null
+++ b/libgo/go/internal/poll/writev_test.go
@@ -0,0 +1,62 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll_test
+
+import (
+	"internal/poll"
+	"reflect"
+	"testing"
+)
+
+func TestConsume(t *testing.T) {
+	tests := []struct {
+		in      [][]byte
+		consume int64
+		want    [][]byte
+	}{
+		{
+			in:      [][]byte{[]byte("foo"), []byte("bar")},
+			consume: 0,
+			want:    [][]byte{[]byte("foo"), []byte("bar")},
+		},
+		{
+			in:      [][]byte{[]byte("foo"), []byte("bar")},
+			consume: 2,
+			want:    [][]byte{[]byte("o"), []byte("bar")},
+		},
+		{
+			in:      [][]byte{[]byte("foo"), []byte("bar")},
+			consume: 3,
+			want:    [][]byte{[]byte("bar")},
+		},
+		{
+			in:      [][]byte{[]byte("foo"), []byte("bar")},
+			consume: 4,
+			want:    [][]byte{[]byte("ar")},
+		},
+		{
+			in:      [][]byte{nil, nil, nil, []byte("bar")},
+			consume: 1,
+			want:    [][]byte{[]byte("ar")},
+		},
+		{
+			in:      [][]byte{nil, nil, nil, []byte("foo")},
+			consume: 0,
+			want:    [][]byte{[]byte("foo")},
+		},
+		{
+			in:      [][]byte{nil, nil, nil},
+			consume: 0,
+			want:    [][]byte{},
+		},
+	}
+	for i, tt := range tests {
+		in := tt.in
+		poll.Consume(&in, tt.consume)
+		if !reflect.DeepEqual(in, tt.want) {
+			t.Errorf("%d. after consume(%d) = %+v, want %+v", i, tt.consume, in, tt.want)
+		}
+	}
+}
diff --git a/libgo/go/internal/testenv/testenv.go b/libgo/go/internal/testenv/testenv.go
index 8d41638..999080b 100644
--- a/libgo/go/internal/testenv/testenv.go
+++ b/libgo/go/internal/testenv/testenv.go
@@ -128,6 +128,22 @@
 	return true
 }
 
+// HasSrc reports whether the entire source tree is available under GOROOT.
+func HasSrc() bool {
+	switch runtime.GOOS {
+	case "nacl":
+		return false
+	case "darwin":
+		if strings.HasPrefix(runtime.GOARCH, "arm") {
+			return false
+		}
+	}
+	if runtime.Compiler == "gccgo" {
+		return false
+	}
+	return true
+}
+
 // MustHaveExec checks that the current system can start new processes
 // using os.StartProcess or (more commonly) exec.Command.
 // If not, MustHaveExec calls t.Skip with an explanation.
diff --git a/libgo/go/internal/testenv/testenv_windows.go b/libgo/go/internal/testenv/testenv_windows.go
index e593f64..eb8d6ac 100644
--- a/libgo/go/internal/testenv/testenv_windows.go
+++ b/libgo/go/internal/testenv/testenv_windows.go
@@ -30,7 +30,6 @@
 			winSymlinkErr = err
 		}
 	}
-	os.Remove("target")
 }
 
 func hasSymlink() (ok bool, reason string) {
diff --git a/libgo/go/internal/trace/parser.go b/libgo/go/internal/trace/parser.go
index efa8540..1dd3ef1 100644
--- a/libgo/go/internal/trace/parser.go
+++ b/libgo/go/internal/trace/parser.go
@@ -40,6 +40,7 @@
 	// for GoUnblock: the associated GoStart
 	// for blocking GoSysCall: the associated GoSysExit
 	// for GoSysExit: the next GoStart
+	// for GCMarkAssistStart: the associated GCMarkAssistDone
 	Link *Event
 }
 
@@ -127,7 +128,7 @@
 		return
 	}
 	switch ver {
-	case 1005, 1007, 1008:
+	case 1005, 1007, 1008, 1009:
 		// Note: When adding a new version, add canned traces
 		// from the old version to the test suite using mkcanned.bash.
 		break
@@ -501,10 +502,11 @@
 		gWaiting
 	)
 	type gdesc struct {
-		state    int
-		ev       *Event
-		evStart  *Event
-		evCreate *Event
+		state        int
+		ev           *Event
+		evStart      *Event
+		evCreate     *Event
+		evMarkAssist *Event
 	}
 	type pdesc struct {
 		running bool
@@ -579,6 +581,18 @@
 				return fmt.Errorf("previous sweeping is not ended before a new one (offset %v, time %v)", ev.Off, ev.Ts)
 			}
 			p.evSweep = ev
+		case EvGCMarkAssistStart:
+			if g.evMarkAssist != nil {
+				return fmt.Errorf("previous mark assist is not ended before a new one (offset %v, time %v)", ev.Off, ev.Ts)
+			}
+			g.evMarkAssist = ev
+		case EvGCMarkAssistDone:
+			// Unlike most events, mark assists can be in progress when a
+			// goroutine starts tracing, so we can't report an error here.
+			if g.evMarkAssist != nil {
+				g.evMarkAssist.Link = ev
+				g.evMarkAssist = nil
+			}
 		case EvGCSweepDone:
 			if p.evSweep == nil {
 				return fmt.Errorf("bogus sweeping end (offset %v, time %v)", ev.Off, ev.Ts)
@@ -835,16 +849,21 @@
 		if ver < 1007 {
 			narg++ // there was an unused arg before 1.7
 		}
+		return narg
+	}
+	narg++ // timestamp
+	if ver < 1007 {
+		narg++ // sequence
+	}
+	switch raw.typ {
+	case EvGCSweepDone:
+		if ver < 1009 {
+			narg -= 2 // 1.9 added two arguments
+		}
 	case EvGCStart, EvGoStart, EvGoUnblock:
 		if ver < 1007 {
 			narg-- // 1.7 added an additional seq arg
 		}
-		fallthrough
-	default:
-		narg++ // timestamp
-		if ver < 1007 {
-			narg++ // sequence
-		}
 	}
 	return narg
 }
@@ -853,52 +872,54 @@
 var BreakTimestampsForTesting bool
 
 // Event types in the trace.
-// Verbatim copy from src/runtime/trace.go.
+// Verbatim copy from src/runtime/trace.go with the "trace" prefix removed.
 const (
-	EvNone           = 0  // unused
-	EvBatch          = 1  // start of per-P batch of events [pid, timestamp]
-	EvFrequency      = 2  // contains tracer timer frequency [frequency (ticks per second)]
-	EvStack          = 3  // stack [stack id, number of PCs, array of {PC, func string ID, file string ID, line}]
-	EvGomaxprocs     = 4  // current value of GOMAXPROCS [timestamp, GOMAXPROCS, stack id]
-	EvProcStart      = 5  // start of P [timestamp, thread id]
-	EvProcStop       = 6  // stop of P [timestamp]
-	EvGCStart        = 7  // GC start [timestamp, seq, stack id]
-	EvGCDone         = 8  // GC done [timestamp]
-	EvGCScanStart    = 9  // GC mark termination start [timestamp]
-	EvGCScanDone     = 10 // GC mark termination done [timestamp]
-	EvGCSweepStart   = 11 // GC sweep start [timestamp, stack id]
-	EvGCSweepDone    = 12 // GC sweep done [timestamp]
-	EvGoCreate       = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]
-	EvGoStart        = 14 // goroutine starts running [timestamp, goroutine id, seq]
-	EvGoEnd          = 15 // goroutine ends [timestamp]
-	EvGoStop         = 16 // goroutine stops (like in select{}) [timestamp, stack]
-	EvGoSched        = 17 // goroutine calls Gosched [timestamp, stack]
-	EvGoPreempt      = 18 // goroutine is preempted [timestamp, stack]
-	EvGoSleep        = 19 // goroutine calls Sleep [timestamp, stack]
-	EvGoBlock        = 20 // goroutine blocks [timestamp, stack]
-	EvGoUnblock      = 21 // goroutine is unblocked [timestamp, goroutine id, seq, stack]
-	EvGoBlockSend    = 22 // goroutine blocks on chan send [timestamp, stack]
-	EvGoBlockRecv    = 23 // goroutine blocks on chan recv [timestamp, stack]
-	EvGoBlockSelect  = 24 // goroutine blocks on select [timestamp, stack]
-	EvGoBlockSync    = 25 // goroutine blocks on Mutex/RWMutex [timestamp, stack]
-	EvGoBlockCond    = 26 // goroutine blocks on Cond [timestamp, stack]
-	EvGoBlockNet     = 27 // goroutine blocks on network [timestamp, stack]
-	EvGoSysCall      = 28 // syscall enter [timestamp, stack]
-	EvGoSysExit      = 29 // syscall exit [timestamp, goroutine id, seq, real timestamp]
-	EvGoSysBlock     = 30 // syscall blocks [timestamp]
-	EvGoWaiting      = 31 // denotes that goroutine is blocked when tracing starts [timestamp, goroutine id]
-	EvGoInSyscall    = 32 // denotes that goroutine is in syscall when tracing starts [timestamp, goroutine id]
-	EvHeapAlloc      = 33 // memstats.heap_live change [timestamp, heap_alloc]
-	EvNextGC         = 34 // memstats.next_gc change [timestamp, next_gc]
-	EvTimerGoroutine = 35 // denotes timer goroutine [timer goroutine id]
-	EvFutileWakeup   = 36 // denotes that the previous wakeup of this goroutine was futile [timestamp]
-	EvString         = 37 // string dictionary entry [ID, length, string]
-	EvGoStartLocal   = 38 // goroutine starts running on the same P as the last event [timestamp, goroutine id]
-	EvGoUnblockLocal = 39 // goroutine is unblocked on the same P as the last event [timestamp, goroutine id, stack]
-	EvGoSysExitLocal = 40 // syscall exit on the same P as the last event [timestamp, goroutine id, real timestamp]
-	EvGoStartLabel   = 41 // goroutine starts running with label [timestamp, goroutine id, seq, label string id]
-	EvGoBlockGC      = 42 // goroutine blocks on GC assist [timestamp, stack]
-	EvCount          = 43
+	EvNone              = 0  // unused
+	EvBatch             = 1  // start of per-P batch of events [pid, timestamp]
+	EvFrequency         = 2  // contains tracer timer frequency [frequency (ticks per second)]
+	EvStack             = 3  // stack [stack id, number of PCs, array of {PC, func string ID, file string ID, line}]
+	EvGomaxprocs        = 4  // current value of GOMAXPROCS [timestamp, GOMAXPROCS, stack id]
+	EvProcStart         = 5  // start of P [timestamp, thread id]
+	EvProcStop          = 6  // stop of P [timestamp]
+	EvGCStart           = 7  // GC start [timestamp, seq, stack id]
+	EvGCDone            = 8  // GC done [timestamp]
+	EvGCScanStart       = 9  // GC mark termination start [timestamp]
+	EvGCScanDone        = 10 // GC mark termination done [timestamp]
+	EvGCSweepStart      = 11 // GC sweep start [timestamp, stack id]
+	EvGCSweepDone       = 12 // GC sweep done [timestamp, swept, reclaimed]
+	EvGoCreate          = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]
+	EvGoStart           = 14 // goroutine starts running [timestamp, goroutine id, seq]
+	EvGoEnd             = 15 // goroutine ends [timestamp]
+	EvGoStop            = 16 // goroutine stops (like in select{}) [timestamp, stack]
+	EvGoSched           = 17 // goroutine calls Gosched [timestamp, stack]
+	EvGoPreempt         = 18 // goroutine is preempted [timestamp, stack]
+	EvGoSleep           = 19 // goroutine calls Sleep [timestamp, stack]
+	EvGoBlock           = 20 // goroutine blocks [timestamp, stack]
+	EvGoUnblock         = 21 // goroutine is unblocked [timestamp, goroutine id, seq, stack]
+	EvGoBlockSend       = 22 // goroutine blocks on chan send [timestamp, stack]
+	EvGoBlockRecv       = 23 // goroutine blocks on chan recv [timestamp, stack]
+	EvGoBlockSelect     = 24 // goroutine blocks on select [timestamp, stack]
+	EvGoBlockSync       = 25 // goroutine blocks on Mutex/RWMutex [timestamp, stack]
+	EvGoBlockCond       = 26 // goroutine blocks on Cond [timestamp, stack]
+	EvGoBlockNet        = 27 // goroutine blocks on network [timestamp, stack]
+	EvGoSysCall         = 28 // syscall enter [timestamp, stack]
+	EvGoSysExit         = 29 // syscall exit [timestamp, goroutine id, seq, real timestamp]
+	EvGoSysBlock        = 30 // syscall blocks [timestamp]
+	EvGoWaiting         = 31 // denotes that goroutine is blocked when tracing starts [timestamp, goroutine id]
+	EvGoInSyscall       = 32 // denotes that goroutine is in syscall when tracing starts [timestamp, goroutine id]
+	EvHeapAlloc         = 33 // memstats.heap_live change [timestamp, heap_alloc]
+	EvNextGC            = 34 // memstats.next_gc change [timestamp, next_gc]
+	EvTimerGoroutine    = 35 // denotes timer goroutine [timer goroutine id]
+	EvFutileWakeup      = 36 // denotes that the previous wakeup of this goroutine was futile [timestamp]
+	EvString            = 37 // string dictionary entry [ID, length, string]
+	EvGoStartLocal      = 38 // goroutine starts running on the same P as the last event [timestamp, goroutine id]
+	EvGoUnblockLocal    = 39 // goroutine is unblocked on the same P as the last event [timestamp, goroutine id, stack]
+	EvGoSysExitLocal    = 40 // syscall exit on the same P as the last event [timestamp, goroutine id, real timestamp]
+	EvGoStartLabel      = 41 // goroutine starts running with label [timestamp, goroutine id, seq, label string id]
+	EvGoBlockGC         = 42 // goroutine blocks on GC assist [timestamp, stack]
+	EvGCMarkAssistStart = 43 // GC mark assist start [timestamp, stack]
+	EvGCMarkAssistDone  = 44 // GC mark assist done [timestamp]
+	EvCount             = 45
 )
 
 var EventDescriptions = [EvCount]struct {
@@ -907,47 +928,49 @@
 	Stack      bool
 	Args       []string
 }{
-	EvNone:           {"None", 1005, false, []string{}},
-	EvBatch:          {"Batch", 1005, false, []string{"p", "ticks"}}, // in 1.5 format it was {"p", "seq", "ticks"}
-	EvFrequency:      {"Frequency", 1005, false, []string{"freq"}},   // in 1.5 format it was {"freq", "unused"}
-	EvStack:          {"Stack", 1005, false, []string{"id", "siz"}},
-	EvGomaxprocs:     {"Gomaxprocs", 1005, true, []string{"procs"}},
-	EvProcStart:      {"ProcStart", 1005, false, []string{"thread"}},
-	EvProcStop:       {"ProcStop", 1005, false, []string{}},
-	EvGCStart:        {"GCStart", 1005, true, []string{"seq"}}, // in 1.5 format it was {}
-	EvGCDone:         {"GCDone", 1005, false, []string{}},
-	EvGCScanStart:    {"GCScanStart", 1005, false, []string{}},
-	EvGCScanDone:     {"GCScanDone", 1005, false, []string{}},
-	EvGCSweepStart:   {"GCSweepStart", 1005, true, []string{}},
-	EvGCSweepDone:    {"GCSweepDone", 1005, false, []string{}},
-	EvGoCreate:       {"GoCreate", 1005, true, []string{"g", "stack"}},
-	EvGoStart:        {"GoStart", 1005, false, []string{"g", "seq"}}, // in 1.5 format it was {"g"}
-	EvGoEnd:          {"GoEnd", 1005, false, []string{}},
-	EvGoStop:         {"GoStop", 1005, true, []string{}},
-	EvGoSched:        {"GoSched", 1005, true, []string{}},
-	EvGoPreempt:      {"GoPreempt", 1005, true, []string{}},
-	EvGoSleep:        {"GoSleep", 1005, true, []string{}},
-	EvGoBlock:        {"GoBlock", 1005, true, []string{}},
-	EvGoUnblock:      {"GoUnblock", 1005, true, []string{"g", "seq"}}, // in 1.5 format it was {"g"}
-	EvGoBlockSend:    {"GoBlockSend", 1005, true, []string{}},
-	EvGoBlockRecv:    {"GoBlockRecv", 1005, true, []string{}},
-	EvGoBlockSelect:  {"GoBlockSelect", 1005, true, []string{}},
-	EvGoBlockSync:    {"GoBlockSync", 1005, true, []string{}},
-	EvGoBlockCond:    {"GoBlockCond", 1005, true, []string{}},
-	EvGoBlockNet:     {"GoBlockNet", 1005, true, []string{}},
-	EvGoSysCall:      {"GoSysCall", 1005, true, []string{}},
-	EvGoSysExit:      {"GoSysExit", 1005, false, []string{"g", "seq", "ts"}},
-	EvGoSysBlock:     {"GoSysBlock", 1005, false, []string{}},
-	EvGoWaiting:      {"GoWaiting", 1005, false, []string{"g"}},
-	EvGoInSyscall:    {"GoInSyscall", 1005, false, []string{"g"}},
-	EvHeapAlloc:      {"HeapAlloc", 1005, false, []string{"mem"}},
-	EvNextGC:         {"NextGC", 1005, false, []string{"mem"}},
-	EvTimerGoroutine: {"TimerGoroutine", 1005, false, []string{"g"}}, // in 1.5 format it was {"g", "unused"}
-	EvFutileWakeup:   {"FutileWakeup", 1005, false, []string{}},
-	EvString:         {"String", 1007, false, []string{}},
-	EvGoStartLocal:   {"GoStartLocal", 1007, false, []string{"g"}},
-	EvGoUnblockLocal: {"GoUnblockLocal", 1007, true, []string{"g"}},
-	EvGoSysExitLocal: {"GoSysExitLocal", 1007, false, []string{"g", "ts"}},
-	EvGoStartLabel:   {"GoStartLabel", 1008, false, []string{"g", "seq", "label"}},
-	EvGoBlockGC:      {"GoBlockGC", 1008, true, []string{}},
+	EvNone:              {"None", 1005, false, []string{}},
+	EvBatch:             {"Batch", 1005, false, []string{"p", "ticks"}}, // in 1.5 format it was {"p", "seq", "ticks"}
+	EvFrequency:         {"Frequency", 1005, false, []string{"freq"}},   // in 1.5 format it was {"freq", "unused"}
+	EvStack:             {"Stack", 1005, false, []string{"id", "siz"}},
+	EvGomaxprocs:        {"Gomaxprocs", 1005, true, []string{"procs"}},
+	EvProcStart:         {"ProcStart", 1005, false, []string{"thread"}},
+	EvProcStop:          {"ProcStop", 1005, false, []string{}},
+	EvGCStart:           {"GCStart", 1005, true, []string{"seq"}}, // in 1.5 format it was {}
+	EvGCDone:            {"GCDone", 1005, false, []string{}},
+	EvGCScanStart:       {"GCScanStart", 1005, false, []string{}},
+	EvGCScanDone:        {"GCScanDone", 1005, false, []string{}},
+	EvGCSweepStart:      {"GCSweepStart", 1005, true, []string{}},
+	EvGCSweepDone:       {"GCSweepDone", 1005, false, []string{"swept", "reclaimed"}}, // before 1.9, format was {}
+	EvGoCreate:          {"GoCreate", 1005, true, []string{"g", "stack"}},
+	EvGoStart:           {"GoStart", 1005, false, []string{"g", "seq"}}, // in 1.5 format it was {"g"}
+	EvGoEnd:             {"GoEnd", 1005, false, []string{}},
+	EvGoStop:            {"GoStop", 1005, true, []string{}},
+	EvGoSched:           {"GoSched", 1005, true, []string{}},
+	EvGoPreempt:         {"GoPreempt", 1005, true, []string{}},
+	EvGoSleep:           {"GoSleep", 1005, true, []string{}},
+	EvGoBlock:           {"GoBlock", 1005, true, []string{}},
+	EvGoUnblock:         {"GoUnblock", 1005, true, []string{"g", "seq"}}, // in 1.5 format it was {"g"}
+	EvGoBlockSend:       {"GoBlockSend", 1005, true, []string{}},
+	EvGoBlockRecv:       {"GoBlockRecv", 1005, true, []string{}},
+	EvGoBlockSelect:     {"GoBlockSelect", 1005, true, []string{}},
+	EvGoBlockSync:       {"GoBlockSync", 1005, true, []string{}},
+	EvGoBlockCond:       {"GoBlockCond", 1005, true, []string{}},
+	EvGoBlockNet:        {"GoBlockNet", 1005, true, []string{}},
+	EvGoSysCall:         {"GoSysCall", 1005, true, []string{}},
+	EvGoSysExit:         {"GoSysExit", 1005, false, []string{"g", "seq", "ts"}},
+	EvGoSysBlock:        {"GoSysBlock", 1005, false, []string{}},
+	EvGoWaiting:         {"GoWaiting", 1005, false, []string{"g"}},
+	EvGoInSyscall:       {"GoInSyscall", 1005, false, []string{"g"}},
+	EvHeapAlloc:         {"HeapAlloc", 1005, false, []string{"mem"}},
+	EvNextGC:            {"NextGC", 1005, false, []string{"mem"}},
+	EvTimerGoroutine:    {"TimerGoroutine", 1005, false, []string{"g"}}, // in 1.5 format it was {"g", "unused"}
+	EvFutileWakeup:      {"FutileWakeup", 1005, false, []string{}},
+	EvString:            {"String", 1007, false, []string{}},
+	EvGoStartLocal:      {"GoStartLocal", 1007, false, []string{"g"}},
+	EvGoUnblockLocal:    {"GoUnblockLocal", 1007, true, []string{"g"}},
+	EvGoSysExitLocal:    {"GoSysExitLocal", 1007, false, []string{"g", "ts"}},
+	EvGoStartLabel:      {"GoStartLabel", 1008, false, []string{"g", "seq", "label"}},
+	EvGoBlockGC:         {"GoBlockGC", 1008, true, []string{}},
+	EvGCMarkAssistStart: {"GCMarkAssistStart", 1009, true, []string{}},
+	EvGCMarkAssistDone:  {"GCMarkAssistDone", 1009, false, []string{}},
 }
diff --git a/libgo/go/internal/trace/writer.go b/libgo/go/internal/trace/writer.go
index a481f50..af5fec8 100644
--- a/libgo/go/internal/trace/writer.go
+++ b/libgo/go/internal/trace/writer.go
@@ -9,7 +9,7 @@
 
 func NewWriter() *Writer {
 	w := new(Writer)
-	w.Write([]byte("go 1.7 trace\x00\x00\x00\x00"))
+	w.Write([]byte("go 1.9 trace\x00\x00\x00\x00"))
 	return w
 }
 
diff --git a/libgo/go/io/example_test.go b/libgo/go/io/example_test.go
index bf16de8..af47853 100644
--- a/libgo/go/io/example_test.go
+++ b/libgo/go/io/example_test.go
@@ -204,6 +204,28 @@
 	// stream
 }
 
+func ExampleSeeker_Seek() {
+	r := strings.NewReader("some io.Reader stream to be read\n")
+	if _, err := io.Copy(os.Stdout, r); err != nil {
+		log.Fatal(err)
+	}
+
+	r.Seek(15, io.SeekStart)
+	if _, err := io.Copy(os.Stdout, r); err != nil {
+		log.Fatal(err)
+	}
+
+	r.Seek(-5, io.SeekEnd)
+	if _, err := io.Copy(os.Stdout, r); err != nil {
+		log.Fatal(err)
+	}
+
+	// Output:
+	// some io.Reader stream to be read
+	// stream to be read
+	// read
+}
+
 func ExampleMultiWriter() {
 	r := strings.NewReader("some io.Reader stream to be read\n")
 
diff --git a/libgo/go/io/io.go b/libgo/go/io/io.go
index 9e4b865..28dab08 100644
--- a/libgo/go/io/io.go
+++ b/libgo/go/io/io.go
@@ -233,7 +233,9 @@
 
 // ByteReader is the interface that wraps the ReadByte method.
 //
-// ReadByte reads and returns the next byte from the input.
+// ReadByte reads and returns the next byte from the input or
+// any error encountered. If ReadByte returns an error, no input
+// byte was consumed, and the returned byte value is undefined.
 type ByteReader interface {
 	ReadByte() (byte, error)
 }
diff --git a/libgo/go/io/ioutil/example_test.go b/libgo/go/io/ioutil/example_test.go
index 74a7791..6edfec1 100644
--- a/libgo/go/io/ioutil/example_test.go
+++ b/libgo/go/io/ioutil/example_test.go
@@ -71,3 +71,15 @@
 		log.Fatal(err)
 	}
 }
+
+func ExampleReadFile() {
+	content, err := ioutil.ReadFile("testdata/hello")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Printf("File contents: %s", content)
+
+	// Output:
+	// File contents: Hello, Gophers!
+}
diff --git a/libgo/go/io/ioutil/tempfile_test.go b/libgo/go/io/ioutil/tempfile_test.go
index 6a70aed..9d54bad 100644
--- a/libgo/go/io/ioutil/tempfile_test.go
+++ b/libgo/go/io/ioutil/tempfile_test.go
@@ -12,12 +12,19 @@
 )
 
 func TestTempFile(t *testing.T) {
-	f, err := TempFile("/_not_exists_", "foo")
+	dir, err := TempDir("", "TestTempFile_BadDir")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	nonexistentDir := filepath.Join(dir, "_not_exists_")
+	f, err := TempFile(nonexistentDir, "foo")
 	if f != nil || err == nil {
-		t.Errorf("TempFile(`/_not_exists_`, `foo`) = %v, %v", f, err)
+		t.Errorf("TempFile(%q, `foo`) = %v, %v", nonexistentDir, f, err)
 	}
 
-	dir := os.TempDir()
+	dir = os.TempDir()
 	f, err = TempFile(dir, "ioutil_test")
 	if f == nil || err != nil {
 		t.Errorf("TempFile(dir, `ioutil_test`) = %v, %v", f, err)
diff --git a/libgo/go/io/multi_test.go b/libgo/go/io/multi_test.go
index 70f2a48..fef3e00 100644
--- a/libgo/go/io/multi_test.go
+++ b/libgo/go/io/multi_test.go
@@ -176,13 +176,26 @@
 	return f(p)
 }
 
+// callDepth returns the logical call depth for the given PCs.
+func callDepth(callers []uintptr) (depth int) {
+	frames := runtime.CallersFrames(callers)
+	more := true
+	for more {
+		_, more = frames.Next()
+		depth++
+	}
+	return
+}
+
 // Test that MultiReader properly flattens chained multiReaders when Read is called
 func TestMultiReaderFlatten(t *testing.T) {
 	pc := make([]uintptr, 1000) // 1000 should fit the full stack
-	var myDepth = runtime.Callers(0, pc)
+	n := runtime.Callers(0, pc)
+	var myDepth = callDepth(pc[:n])
 	var readDepth int // will contain the depth from which fakeReader.Read was called
 	var r Reader = MultiReader(readerFunc(func(p []byte) (int, error) {
-		readDepth = runtime.Callers(1, pc)
+		n := runtime.Callers(1, pc)
+		readDepth = callDepth(pc[:n])
 		return 0, errors.New("irrelevant")
 	}))
 
@@ -244,14 +257,17 @@
 
 	var mr Reader
 	closed := make(chan struct{})
-	{
+	// The closure ensures that we don't have a live reference to buf1
+	// on our stack after MultiReader is inlined (Issue 18819).  This
+	// is a work around for a limitation in liveness analysis.
+	func() {
 		buf1 := bytes.NewReader([]byte("foo"))
 		buf2 := bytes.NewReader([]byte("bar"))
 		mr = MultiReader(buf1, buf2)
 		runtime.SetFinalizer(buf1, func(*bytes.Reader) {
 			close(closed)
 		})
-	}
+	}()
 
 	buf := make([]byte, 4)
 	if n, err := ReadFull(mr, buf); err != nil || string(buf) != "foob" {
diff --git a/libgo/go/log/log.go b/libgo/go/log/log.go
index 58b8788..587904b 100644
--- a/libgo/go/log/log.go
+++ b/libgo/go/log/log.go
@@ -72,7 +72,7 @@
 
 var std = New(os.Stderr, "", LstdFlags)
 
-// Cheap integer to fixed-width decimal ASCII.  Give a negative width to avoid zero-padding.
+// Cheap integer to fixed-width decimal ASCII. Give a negative width to avoid zero-padding.
 func itoa(buf *[]byte, i int, wid int) {
 	// Assemble decimal in reverse order.
 	var b [20]byte
@@ -89,12 +89,16 @@
 	*buf = append(*buf, b[bp:]...)
 }
 
+// formatHeader writes log header to buf in following order:
+//   * l.prefix (if it's not blank),
+//   * date and/or time (if corresponding flags are provided),
+//   * file and line number (if corresponding flags are provided).
 func (l *Logger) formatHeader(buf *[]byte, t time.Time, file string, line int) {
 	*buf = append(*buf, l.prefix...)
-	if l.flag&LUTC != 0 {
-		t = t.UTC()
-	}
 	if l.flag&(Ldate|Ltime|Lmicroseconds) != 0 {
+		if l.flag&LUTC != 0 {
+			t = t.UTC()
+		}
 		if l.flag&Ldate != 0 {
 			year, month, day := t.Date()
 			itoa(buf, year, 4)
@@ -143,13 +147,17 @@
 // provided for generality, although at the moment on all pre-defined
 // paths it will be 2.
 func (l *Logger) Output(calldepth int, s string) error {
-	now := time.Now() // get this early.
+	// Get time early if we need it.
+	var now time.Time
+	if l.flag&(Ldate|Ltime|Lmicroseconds) != 0 {
+		now = time.Now()
+	}
 	var file string
 	var line int
 	l.mu.Lock()
 	defer l.mu.Unlock()
 	if l.flag&(Lshortfile|Llongfile) != 0 {
-		// release lock while getting caller info - it's expensive.
+		// Release lock while getting caller info - it's expensive.
 		l.mu.Unlock()
 		var ok bool
 		_, file, line, ok = runtime.Caller(calldepth)
diff --git a/libgo/go/log/log_test.go b/libgo/go/log/log_test.go
index dd16c9d..966fdf3 100644
--- a/libgo/go/log/log_test.go
+++ b/libgo/go/log/log_test.go
@@ -182,3 +182,13 @@
 		l.Println(testString)
 	}
 }
+
+func BenchmarkPrintlnNoFlags(b *testing.B) {
+	const testString = "test"
+	var buf bytes.Buffer
+	l := New(&buf, "", 0)
+	for i := 0; i < b.N; i++ {
+		buf.Reset()
+		l.Println(testString)
+	}
+}
diff --git a/libgo/go/log/syslog/syslog.go b/libgo/go/log/syslog/syslog.go
index df9ffb8..dfd0028 100644
--- a/libgo/go/log/syslog/syslog.go
+++ b/libgo/go/log/syslog/syslog.go
@@ -102,15 +102,16 @@
 
 // New establishes a new connection to the system log daemon. Each
 // write to the returned writer sends a log message with the given
-// priority and prefix.
+// priority (a combination of the syslog facility and severity) and
+// prefix tag. If tag is empty, the os.Args[0] is used.
 func New(priority Priority, tag string) (*Writer, error) {
 	return Dial("", "", priority, tag)
 }
 
 // Dial establishes a connection to a log daemon by connecting to
 // address raddr on the specified network. Each write to the returned
-// writer sends a log message with the given facility, severity and
-// tag.
+// writer sends a log message with the facility and severity
+// (from priority) and tag. If tag is empty, the os.Args[0] is used.
 // If network is empty, Dial will connect to the local syslog server.
 // Otherwise, see the documentation for net.Dial for valid values
 // of network and raddr.
@@ -301,10 +302,10 @@
 	return n.conn.Close()
 }
 
-// NewLogger creates a log.Logger whose output is written to
-// the system log service with the specified priority. The logFlag
-// argument is the flag set passed through to log.New to create
-// the Logger.
+// NewLogger creates a log.Logger whose output is written to the
+// system log service with the specified priority, a combination of
+// the syslog facility and severity. The logFlag argument is the flag
+// set passed through to log.New to create the Logger.
 func NewLogger(p Priority, logFlag int) (*log.Logger, error) {
 	s, err := New(p, "")
 	if err != nil {
diff --git a/libgo/go/math/acosh.go b/libgo/go/math/acosh.go
index dce21b2..97e84d0 100644
--- a/libgo/go/math/acosh.go
+++ b/libgo/go/math/acosh.go
@@ -40,6 +40,13 @@
 //	Acosh(x) = NaN if x < 1
 //	Acosh(NaN) = NaN
 func Acosh(x float64) float64 {
+	return libc_acosh(x)
+}
+
+//extern acosh
+func libc_acosh(float64) float64
+
+func acosh(x float64) float64 {
 	const (
 		Ln2   = 6.93147180559945286227e-01 // 0x3FE62E42FEFA39EF
 		Large = 1 << 28                    // 2**28
diff --git a/libgo/go/math/all_test.go b/libgo/go/math/all_test.go
index 3d8cd72..39a3a49 100644
--- a/libgo/go/math/all_test.go
+++ b/libgo/go/math/all_test.go
@@ -947,6 +947,11 @@
 	2000,
 	Inf(1),
 	NaN(),
+	// smallest float64 that overflows Exp(x)
+	7.097827128933841e+02,
+	// Issue 18912
+	1.48852223e+09,
+	1.4885222e+09,
 }
 var expSC = []float64{
 	0,
@@ -954,6 +959,27 @@
 	Inf(1),
 	Inf(1),
 	NaN(),
+	Inf(1),
+	Inf(1),
+	Inf(1),
+}
+
+var vfexp2SC = []float64{
+	Inf(-1),
+	-2000,
+	2000,
+	Inf(1),
+	NaN(),
+	// smallest float64 that overflows Exp2(x)
+	1024,
+}
+var exp2SC = []float64{
+	0,
+	0,
+	Inf(1),
+	Inf(1),
+	NaN(),
+	Inf(1),
 }
 
 var vfexpm1SC = []float64{
@@ -1620,16 +1646,38 @@
 
 var vfpow10SC = []int{
 	MinInt32,
-	MaxInt32,
-	-325,
+	-324,
+	-323,
+	-50,
+	-22,
+	-1,
+	0,
+	1,
+	22,
+	50,
+	100,
+	200,
+	308,
 	309,
+	MaxInt32,
 }
 
 var pow10SC = []float64{
-	0,      // pow10(MinInt32)
-	Inf(1), // pow10(MaxInt32)
-	0,      // pow10(-325)
-	Inf(1), // pow10(309)
+	0,        // pow10(MinInt32)
+	0,        // pow10(-324)
+	1.0e-323, // pow10(-323)
+	1.0e-50,  // pow10(-50)
+	1.0e-22,  // pow10(-22)
+	1.0e-1,   // pow10(-1)
+	1.0e0,    // pow10(0)
+	1.0e1,    // pow10(1)
+	1.0e22,   // pow10(22)
+	1.0e50,   // pow10(50)
+	1.0e100,  // pow10(100)
+	1.0e200,  // pow10(200)
+	1.0e308,  // pow10(308)
+	Inf(1),   // pow10(309)
+	Inf(1),   // pow10(MaxInt32)
 }
 
 var vfsignbitSC = []float64{
@@ -1716,30 +1764,35 @@
 	0,
 	Inf(1),
 	NaN(),
+	-1,
 }
 var y0SC = []float64{
 	NaN(),
 	Inf(-1),
 	0,
 	NaN(),
+	NaN(),
 }
 var y1SC = []float64{
 	NaN(),
 	Inf(-1),
 	0,
 	NaN(),
+	NaN(),
 }
 var y2SC = []float64{
 	NaN(),
 	Inf(-1),
 	0,
 	NaN(),
+	NaN(),
 }
 var yM3SC = []float64{
 	NaN(),
 	Inf(1),
 	0,
 	NaN(),
+	NaN(),
 }
 
 // arguments and expected results for boundary cases
@@ -2089,8 +2142,8 @@
 			t.Errorf("%s(%g) = %g, want %g", name, vf[i], f, exp2[i])
 		}
 	}
-	for i := 0; i < len(vfexpSC); i++ {
-		if f := Exp2(vfexpSC[i]); !alike(expSC[i], f) {
+	for i := 0; i < len(vfexp2SC); i++ {
+		if f := Exp2(vfexp2SC[i]); !alike(exp2SC[i], f) {
 			t.Errorf("%s(%g) = %g, want %g", name, vfexpSC[i], f, expSC[i])
 		}
 	}
@@ -2690,6 +2743,9 @@
 			t.Errorf("Yn(-3, %g) = %g, want %g", vfy0SC[i], f, yM3SC[i])
 		}
 	}
+	if f := Yn(0, 0); !alike(Inf(-1), f) {
+		t.Errorf("Yn(0, 0) = %g, want %g", f, Inf(-1))
+	}
 }
 
 // Check that math functions of high angle values
@@ -2768,327 +2824,452 @@
 
 // Benchmarks
 
+// Global exported variables are used to store the
+// return values of functions measured in the benchmarks.
+// Storing the results in these variables prevents the compiler
+// from completely optimizing the benchmarked functions away.
+var (
+	GlobalI int
+	GlobalB bool
+	GlobalF float64
+)
+
 func BenchmarkAcos(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Acos(.5)
+		x = Acos(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkAcosh(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Acosh(1.5)
+		x = Acosh(1.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkAsin(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Asin(.5)
+		x = Asin(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkAsinh(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Asinh(.5)
+		x = Asinh(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkAtan(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Atan(.5)
+		x = Atan(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkAtanh(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Atanh(.5)
+		x = Atanh(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkAtan2(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Atan2(.5, 1)
+		x = Atan2(.5, 1)
 	}
+	GlobalF = x
 }
 
 func BenchmarkCbrt(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Cbrt(10)
+		x = Cbrt(10)
 	}
+	GlobalF = x
 }
 
 func BenchmarkCeil(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Ceil(.5)
+		x = Ceil(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkCopysign(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Copysign(.5, -1)
+		x = Copysign(.5, -1)
 	}
+	GlobalF = x
 }
 
 func BenchmarkCos(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Cos(.5)
+		x = Cos(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkCosh(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Cosh(2.5)
+		x = Cosh(2.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkErf(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Erf(.5)
+		x = Erf(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkErfc(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Erfc(.5)
+		x = Erfc(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkExp(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Exp(.5)
+		x = Exp(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkExpGo(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		ExpGo(.5)
+		x = ExpGo(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkExpm1(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Expm1(.5)
+		x = Expm1(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkExp2(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Exp2(.5)
+		x = Exp2(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkExp2Go(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Exp2Go(.5)
+		x = Exp2Go(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkAbs(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Abs(.5)
+		x = Abs(.5)
 	}
+	GlobalF = x
+
 }
 
 func BenchmarkDim(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Dim(10, 3)
+		x = Dim(10, 3)
 	}
+	GlobalF = x
 }
 
 func BenchmarkFloor(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Floor(.5)
+		x = Floor(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkMax(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Max(10, 3)
+		x = Max(10, 3)
 	}
+	GlobalF = x
 }
 
 func BenchmarkMin(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Min(10, 3)
+		x = Min(10, 3)
 	}
+	GlobalF = x
 }
 
 func BenchmarkMod(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Mod(10, 3)
+		x = Mod(10, 3)
 	}
+	GlobalF = x
 }
 
 func BenchmarkFrexp(b *testing.B) {
+	x := 0.0
+	y := 0
 	for i := 0; i < b.N; i++ {
-		Frexp(8)
+		x, y = Frexp(8)
 	}
+	GlobalF = x
+	GlobalI = y
 }
 
 func BenchmarkGamma(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Gamma(2.5)
+		x = Gamma(2.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkHypot(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Hypot(3, 4)
+		x = Hypot(3, 4)
 	}
+	GlobalF = x
 }
 
 func BenchmarkHypotGo(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		HypotGo(3, 4)
+		x = HypotGo(3, 4)
 	}
+	GlobalF = x
 }
 
 func BenchmarkIlogb(b *testing.B) {
+	x := 0
 	for i := 0; i < b.N; i++ {
-		Ilogb(.5)
+		x = Ilogb(.5)
 	}
+	GlobalI = x
 }
 
 func BenchmarkJ0(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		J0(2.5)
+		x = J0(2.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkJ1(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		J1(2.5)
+		x = J1(2.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkJn(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Jn(2, 2.5)
+		x = Jn(2, 2.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkLdexp(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Ldexp(.5, 2)
+		x = Ldexp(.5, 2)
 	}
+	GlobalF = x
 }
 
 func BenchmarkLgamma(b *testing.B) {
+	x := 0.0
+	y := 0
 	for i := 0; i < b.N; i++ {
-		Lgamma(2.5)
+		x, y = Lgamma(2.5)
 	}
+	GlobalF = x
+	GlobalI = y
 }
 
 func BenchmarkLog(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Log(.5)
+		x = Log(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkLogb(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Logb(.5)
+		x = Logb(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkLog1p(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Log1p(.5)
+		x = Log1p(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkLog10(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Log10(.5)
+		x = Log10(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkLog2(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Log2(.5)
+		x = Log2(.5)
 	}
+	GlobalF += x
 }
 
 func BenchmarkModf(b *testing.B) {
+	x := 0.0
+	y := 0.0
 	for i := 0; i < b.N; i++ {
-		Modf(1.5)
+		x, y = Modf(1.5)
 	}
+	GlobalF += x
+	GlobalF += y
 }
 
 func BenchmarkNextafter32(b *testing.B) {
+	x := float32(0.0)
 	for i := 0; i < b.N; i++ {
-		Nextafter32(.5, 1)
+		x = Nextafter32(.5, 1)
 	}
+	GlobalF = float64(x)
 }
 
 func BenchmarkNextafter64(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Nextafter(.5, 1)
+		x = Nextafter(.5, 1)
 	}
+	GlobalF = x
 }
 
 func BenchmarkPowInt(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Pow(2, 2)
+		x = Pow(2, 2)
 	}
+	GlobalF = x
 }
 
 func BenchmarkPowFrac(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Pow(2.5, 1.5)
+		x = Pow(2.5, 1.5)
 	}
+	GlobalF = x
 }
 
+var pow10pos = int(300)
+
 func BenchmarkPow10Pos(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Pow10(300)
+		x = Pow10(pow10pos)
 	}
+	GlobalF = x
 }
 
+var pow10neg = int(-300)
+
 func BenchmarkPow10Neg(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Pow10(-300)
+		x = Pow10(pow10neg)
 	}
+	GlobalF = x
 }
 
 func BenchmarkRemainder(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Remainder(10, 3)
+		x = Remainder(10, 3)
 	}
+	GlobalF = x
 }
 
 func BenchmarkSignbit(b *testing.B) {
+	x := false
 	for i := 0; i < b.N; i++ {
-		Signbit(2.5)
+		x = Signbit(2.5)
 	}
+	GlobalB = x
 }
 
 func BenchmarkSin(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Sin(.5)
+		x = Sin(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkSincos(b *testing.B) {
+	x := 0.0
+	y := 0.0
 	for i := 0; i < b.N; i++ {
-		Sincos(.5)
+		x, y = Sincos(.5)
 	}
+	GlobalF += x
+	GlobalF += y
 }
 
 func BenchmarkSinh(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Sinh(2.5)
+		x = Sinh(2.5)
 	}
+	GlobalF = x
 }
 
-var Global float64
-
 func BenchmarkSqrtIndirect(b *testing.B) {
 	x, y := 0.0, 10.0
 	f := Sqrt
 	for i := 0; i < b.N; i++ {
 		x += f(y)
 	}
-	Global = x
+	GlobalF = x
 }
 
 func BenchmarkSqrtLatency(b *testing.B) {
@@ -3096,7 +3277,7 @@
 	for i := 0; i < b.N; i++ {
 		x = Sqrt(x)
 	}
-	Global = x
+	GlobalF = x
 }
 
 func BenchmarkSqrtIndirectLatency(b *testing.B) {
@@ -3105,7 +3286,7 @@
 	for i := 0; i < b.N; i++ {
 		x = f(x)
 	}
-	Global = x
+	GlobalF = x
 }
 
 func BenchmarkSqrtGoLatency(b *testing.B) {
@@ -3113,7 +3294,7 @@
 	for i := 0; i < b.N; i++ {
 		x = SqrtGo(x)
 	}
-	Global = x
+	GlobalF = x
 }
 
 func isPrime(i int) bool {
@@ -3131,48 +3312,56 @@
 }
 
 func BenchmarkSqrtPrime(b *testing.B) {
-	any := false
+	x := false
 	for i := 0; i < b.N; i++ {
-		if isPrime(100003) {
-			any = true
-		}
+		x = isPrime(100003)
 	}
-	if any {
-		Global = 1
-	}
+	GlobalB = x
 }
 
 func BenchmarkTan(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Tan(.5)
+		x = Tan(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkTanh(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Tanh(2.5)
+		x = Tanh(2.5)
 	}
+	GlobalF = x
 }
 func BenchmarkTrunc(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Trunc(.5)
+		x = Trunc(.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkY0(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Y0(2.5)
+		x = Y0(2.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkY1(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Y1(2.5)
+		x = Y1(2.5)
 	}
+	GlobalF = x
 }
 
 func BenchmarkYn(b *testing.B) {
+	x := 0.0
 	for i := 0; i < b.N; i++ {
-		Yn(2, 2.5)
+		x = Yn(2, 2.5)
 	}
+	GlobalF = x
 }
diff --git a/libgo/go/math/arith_s390x.go b/libgo/go/math/arith_s390x.go
index 937f25f..8d1fa6a 100644
--- a/libgo/go/math/arith_s390x.go
+++ b/libgo/go/math/arith_s390x.go
@@ -24,6 +24,54 @@
 func tanhTrampolineSetup(x float64) float64
 func tanhAsm(x float64) float64
 
+func log1pTrampolineSetup(x float64) float64
+func log1pAsm(x float64) float64
+
+func atanhTrampolineSetup(x float64) float64
+func atanhAsm(x float64) float64
+
+func acosTrampolineSetup(x float64) float64
+func acosAsm(x float64) float64
+
+func acoshTrampolineSetup(x float64) float64
+func acoshAsm(x float64) float64
+
+func asinTrampolineSetup(x float64) float64
+func asinAsm(x float64) float64
+
+func asinhTrampolineSetup(x float64) float64
+func asinhAsm(x float64) float64
+
+func erfTrampolineSetup(x float64) float64
+func erfAsm(x float64) float64
+
+func erfcTrampolineSetup(x float64) float64
+func erfcAsm(x float64) float64
+
+func atanTrampolineSetup(x float64) float64
+func atanAsm(x float64) float64
+
+func atan2TrampolineSetup(x, y float64) float64
+func atan2Asm(x, y float64) float64
+
+func cbrtTrampolineSetup(x float64) float64
+func cbrtAsm(x float64) float64
+
+func logTrampolineSetup(x float64) float64
+func logAsm(x float64) float64
+
+func tanTrampolineSetup(x float64) float64
+func tanAsm(x float64) float64
+
+func expTrampolineSetup(x float64) float64
+func expAsm(x float64) float64
+
+func expm1TrampolineSetup(x float64) float64
+func expm1Asm(x float64) float64
+
+func powTrampolineSetup(x, y float64) float64
+func powAsm(x, y float64) float64
+
 // hasVectorFacility reports whether the machine has the z/Architecture
 // vector facility installed and enabled.
 func hasVectorFacility() bool
diff --git a/libgo/go/math/arith_s390x_test.go b/libgo/go/math/arith_s390x_test.go
index fd3e8ca..23e5245 100644
--- a/libgo/go/math/arith_s390x_test.go
+++ b/libgo/go/math/arith_s390x_test.go
@@ -108,6 +108,37 @@
 	}
 }
 
+func TestLargeTanNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	large := float64(100000 * Pi)
+	for i := 0; i < len(vf); i++ {
+		f1 := tanLarge[i]
+		f2 := TanNovec(vf[i] + large)
+		if !close(f1, f2) {
+			t.Errorf("Tan(%g) = %g, want %g", vf[i]+large, f2, f1)
+		}
+	}
+}
+
+func TestTanNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		if f := TanNovec(vf[i]); !veryclose(tan[i], f) {
+			t.Errorf("Tan(%g) = %g, want %g", vf[i], f, tan[i])
+		}
+	}
+	// same special cases as Sin
+	for i := 0; i < len(vfsinSC); i++ {
+		if f := TanNovec(vfsinSC[i]); !alike(sinSC[i], f) {
+			t.Errorf("Tan(%g) = %g, want %g", vfsinSC[i], f, sinSC[i])
+		}
+	}
+}
+
 func TestTanhNovec(t *testing.T) {
 	if !HasVX {
 		t.Skipf("no vector support")
@@ -144,3 +175,270 @@
 		}
 	}
 }
+
+func TestLog1pNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] / 100
+		if f := Log1pNovec(a); !veryclose(log1p[i], f) {
+			t.Errorf("Log1p(%g) = %g, want %g", a, f, log1p[i])
+		}
+	}
+	a := 9.0
+	if f := Log1pNovec(a); f != Ln10 {
+		t.Errorf("Log1p(%g) = %g, want %g", a, f, Ln10)
+	}
+	for i := 0; i < len(vflogSC); i++ {
+		if f := Log1pNovec(vflog1pSC[i]); !alike(log1pSC[i], f) {
+			t.Errorf("Log1p(%g) = %g, want %g", vflog1pSC[i], f, log1pSC[i])
+		}
+	}
+}
+
+func TestAtanhNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] / 10
+		if f := AtanhNovec(a); !veryclose(atanh[i], f) {
+			t.Errorf("Atanh(%g) = %g, want %g", a, f, atanh[i])
+		}
+	}
+	for i := 0; i < len(vfatanhSC); i++ {
+		if f := AtanhNovec(vfatanhSC[i]); !alike(atanhSC[i], f) {
+			t.Errorf("Atanh(%g) = %g, want %g", vfatanhSC[i], f, atanhSC[i])
+		}
+	}
+}
+
+func TestAcosNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] / 10
+		if f := AcosNovec(a); !close(acos[i], f) {
+			t.Errorf("Acos(%g) = %g, want %g", a, f, acos[i])
+		}
+	}
+	for i := 0; i < len(vfacosSC); i++ {
+		if f := AcosNovec(vfacosSC[i]); !alike(acosSC[i], f) {
+			t.Errorf("Acos(%g) = %g, want %g", vfacosSC[i], f, acosSC[i])
+		}
+	}
+}
+
+func TestAsinNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] / 10
+		if f := AsinNovec(a); !veryclose(asin[i], f) {
+			t.Errorf("Asin(%g) = %g, want %g", a, f, asin[i])
+		}
+	}
+	for i := 0; i < len(vfasinSC); i++ {
+		if f := AsinNovec(vfasinSC[i]); !alike(asinSC[i], f) {
+			t.Errorf("Asin(%g) = %g, want %g", vfasinSC[i], f, asinSC[i])
+		}
+	}
+}
+
+func TestAcoshNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := 1 + Abs(vf[i])
+		if f := AcoshNovec(a); !veryclose(acosh[i], f) {
+			t.Errorf("Acosh(%g) = %g, want %g", a, f, acosh[i])
+		}
+	}
+	for i := 0; i < len(vfacoshSC); i++ {
+		if f := AcoshNovec(vfacoshSC[i]); !alike(acoshSC[i], f) {
+			t.Errorf("Acosh(%g) = %g, want %g", vfacoshSC[i], f, acoshSC[i])
+		}
+	}
+}
+
+func TestAsinhNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		if f := AsinhNovec(vf[i]); !veryclose(asinh[i], f) {
+			t.Errorf("Asinh(%g) = %g, want %g", vf[i], f, asinh[i])
+		}
+	}
+	for i := 0; i < len(vfasinhSC); i++ {
+		if f := AsinhNovec(vfasinhSC[i]); !alike(asinhSC[i], f) {
+			t.Errorf("Asinh(%g) = %g, want %g", vfasinhSC[i], f, asinhSC[i])
+		}
+	}
+}
+
+func TestErfNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] / 10
+		if f := ErfNovec(a); !veryclose(erf[i], f) {
+			t.Errorf("Erf(%g) = %g, want %g", a, f, erf[i])
+		}
+	}
+	for i := 0; i < len(vferfSC); i++ {
+		if f := ErfNovec(vferfSC[i]); !alike(erfSC[i], f) {
+			t.Errorf("Erf(%g) = %g, want %g", vferfSC[i], f, erfSC[i])
+		}
+	}
+}
+
+func TestErfcNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] / 10
+		if f := ErfcNovec(a); !veryclose(erfc[i], f) {
+			t.Errorf("Erfc(%g) = %g, want %g", a, f, erfc[i])
+		}
+	}
+	for i := 0; i < len(vferfcSC); i++ {
+		if f := ErfcNovec(vferfcSC[i]); !alike(erfcSC[i], f) {
+			t.Errorf("Erfc(%g) = %g, want %g", vferfcSC[i], f, erfcSC[i])
+		}
+	}
+}
+
+func TestAtanNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		if f := AtanNovec(vf[i]); !veryclose(atan[i], f) {
+			t.Errorf("Atan(%g) = %g, want %g", vf[i], f, atan[i])
+		}
+	}
+	for i := 0; i < len(vfatanSC); i++ {
+		if f := AtanNovec(vfatanSC[i]); !alike(atanSC[i], f) {
+			t.Errorf("Atan(%g) = %g, want %g", vfatanSC[i], f, atanSC[i])
+		}
+	}
+}
+
+func TestAtan2Novec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		if f := Atan2Novec(10, vf[i]); !veryclose(atan2[i], f) {
+			t.Errorf("Atan2(10, %g) = %g, want %g", vf[i], f, atan2[i])
+		}
+	}
+	for i := 0; i < len(vfatan2SC); i++ {
+		if f := Atan2Novec(vfatan2SC[i][0], vfatan2SC[i][1]); !alike(atan2SC[i], f) {
+			t.Errorf("Atan2(%g, %g) = %g, want %g", vfatan2SC[i][0], vfatan2SC[i][1], f, atan2SC[i])
+		}
+	}
+}
+
+func TestCbrtNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		if f := CbrtNovec(vf[i]); !veryclose(cbrt[i], f) {
+			t.Errorf("Cbrt(%g) = %g, want %g", vf[i], f, cbrt[i])
+		}
+	}
+	for i := 0; i < len(vfcbrtSC); i++ {
+		if f := CbrtNovec(vfcbrtSC[i]); !alike(cbrtSC[i], f) {
+			t.Errorf("Cbrt(%g) = %g, want %g", vfcbrtSC[i], f, cbrtSC[i])
+		}
+	}
+}
+
+func TestLogNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := Abs(vf[i])
+		if f := LogNovec(a); log[i] != f {
+			t.Errorf("Log(%g) = %g, want %g", a, f, log[i])
+		}
+	}
+	if f := LogNovec(10); f != Ln10 {
+		t.Errorf("Log(%g) = %g, want %g", 10.0, f, Ln10)
+	}
+	for i := 0; i < len(vflogSC); i++ {
+		if f := LogNovec(vflogSC[i]); !alike(logSC[i], f) {
+			t.Errorf("Log(%g) = %g, want %g", vflogSC[i], f, logSC[i])
+		}
+	}
+}
+
+func TestExpNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	testExpNovec(t, Exp, "Exp")
+	testExpNovec(t, ExpGo, "ExpGo")
+}
+
+func testExpNovec(t *testing.T, Exp func(float64) float64, name string) {
+	for i := 0; i < len(vf); i++ {
+		if f := ExpNovec(vf[i]); !veryclose(exp[i], f) {
+			t.Errorf("%s(%g) = %g, want %g", name, vf[i], f, exp[i])
+		}
+	}
+	for i := 0; i < len(vfexpSC); i++ {
+		if f := ExpNovec(vfexpSC[i]); !alike(expSC[i], f) {
+			t.Errorf("%s(%g) = %g, want %g", name, vfexpSC[i], f, expSC[i])
+		}
+	}
+}
+
+func TestExpm1Novec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] / 100
+		if f := Expm1Novec(a); !veryclose(expm1[i], f) {
+			t.Errorf("Expm1(%g) = %g, want %g", a, f, expm1[i])
+		}
+	}
+	for i := 0; i < len(vf); i++ {
+		a := vf[i] * 10
+		if f := Expm1Novec(a); !close(expm1Large[i], f) {
+			t.Errorf("Expm1(%g) = %g, want %g", a, f, expm1Large[i])
+		}
+	}
+	for i := 0; i < len(vfexpm1SC); i++ {
+		if f := Expm1Novec(vfexpm1SC[i]); !alike(expm1SC[i], f) {
+			t.Errorf("Expm1(%g) = %g, want %g", vfexpm1SC[i], f, expm1SC[i])
+		}
+	}
+}
+
+func TestPowNovec(t *testing.T) {
+	if !HasVX {
+		t.Skipf("no vector support")
+	}
+	for i := 0; i < len(vf); i++ {
+		if f := PowNovec(10, vf[i]); !close(pow[i], f) {
+			t.Errorf("Pow(10, %g) = %g, want %g", vf[i], f, pow[i])
+		}
+	}
+	for i := 0; i < len(vfpowSC); i++ {
+		if f := PowNovec(vfpowSC[i][0], vfpowSC[i][1]); !alike(powSC[i], f) {
+			t.Errorf("Pow(%g, %g) = %g, want %g", vfpowSC[i][0], vfpowSC[i][1], f, powSC[i])
+		}
+	}
+}
diff --git a/libgo/go/math/asinh.go b/libgo/go/math/asinh.go
index 3b793b0..d5e6512 100644
--- a/libgo/go/math/asinh.go
+++ b/libgo/go/math/asinh.go
@@ -37,6 +37,13 @@
 //	Asinh(±Inf) = ±Inf
 //	Asinh(NaN) = NaN
 func Asinh(x float64) float64 {
+	return libc_asinh(x)
+}
+
+//extern asinh
+func libc_asinh(float64) float64
+
+func asinh(x float64) float64 {
 	const (
 		Ln2      = 6.93147180559945286227e-01 // 0x3FE62E42FEFA39EF
 		NearZero = 1.0 / (1 << 28)            // 2**-28
diff --git a/libgo/go/math/atanh.go b/libgo/go/math/atanh.go
index d59a847..c62c1c0 100644
--- a/libgo/go/math/atanh.go
+++ b/libgo/go/math/atanh.go
@@ -45,6 +45,13 @@
 //	Atanh(x) = NaN if x < -1 or x > 1
 //	Atanh(NaN) = NaN
 func Atanh(x float64) float64 {
+	return libc_atanh(x)
+}
+
+//extern atanh
+func libc_atanh(float64) float64
+
+func atanh(x float64) float64 {
 	const NearZero = 1.0 / (1 << 28) // 2**-28
 	// special cases
 	switch {
diff --git a/libgo/go/math/big/arith.go b/libgo/go/math/big/arith.go
index d7ea838..ad35240 100644
--- a/libgo/go/math/big/arith.go
+++ b/libgo/go/math/big/arith.go
@@ -8,18 +8,17 @@
 
 package big
 
+import "math/bits"
+
 // A Word represents a single digit of a multi-precision unsigned integer.
-type Word uintptr
+type Word uint
 
 const (
-	// Compute the size _S of a Word in bytes.
-	_m    = ^Word(0)
-	_logS = _m>>8&1 + _m>>16&1 + _m>>32&1
-	_S    = 1 << _logS
+	_S = _W / 8 // word size in bytes
 
-	_W = _S << 3 // word size in bits
-	_B = 1 << _W // digit base
-	_M = _B - 1  // digit mask
+	_W = bits.UintSize // word size in bits
+	_B = 1 << _W       // digit base
+	_M = _B - 1        // digit mask
 
 	_W2 = _W / 2   // half word size in bits
 	_B2 = 1 << _W2 // half digit base
@@ -77,54 +76,10 @@
 	return
 }
 
-// Length of x in bits.
-func bitLen_g(x Word) (n int) {
-	for ; x >= 0x8000; x >>= 16 {
-		n += 16
-	}
-	if x >= 0x80 {
-		x >>= 8
-		n += 8
-	}
-	if x >= 0x8 {
-		x >>= 4
-		n += 4
-	}
-	if x >= 0x2 {
-		x >>= 2
-		n += 2
-	}
-	if x >= 0x1 {
-		n++
-	}
-	return
-}
-
-// log2 computes the integer binary logarithm of x.
-// The result is the integer n for which 2^n <= x < 2^(n+1).
-// If x == 0, the result is -1.
-func log2(x Word) int {
-	return bitLen(x) - 1
-}
-
 // nlz returns the number of leading zeros in x.
+// Wraps bits.LeadingZeros call for convenience.
 func nlz(x Word) uint {
-	return uint(_W - bitLen(x))
-}
-
-// nlz64 returns the number of leading zeros in x.
-func nlz64(x uint64) uint {
-	switch _W {
-	case 32:
-		w := x >> 32
-		if w == 0 {
-			return 32 + nlz(Word(x))
-		}
-		return nlz(Word(w))
-	case 64:
-		return nlz(Word(x))
-	}
-	panic("unreachable")
+	return uint(bits.LeadingZeros(uint(x)))
 }
 
 // q = (u1<<_W + u0 - r)/y
diff --git a/libgo/go/math/big/arith_decl.go b/libgo/go/math/big/arith_decl.go
index 5538833..61df0df 100644
--- a/libgo/go/math/big/arith_decl.go
+++ b/libgo/go/math/big/arith_decl.go
@@ -19,4 +19,3 @@
 func mulAddVWW(z, x []Word, y, r Word) (c Word)
 func addMulVVW(z, x []Word, y Word) (c Word)
 func divWVW(z []Word, xn Word, x []Word, y Word) (r Word)
-func bitLen(x Word) (n int)
diff --git a/libgo/go/math/big/arith_decl_pure.go b/libgo/go/math/big/arith_decl_pure.go
index 5c04414..0988419 100644
--- a/libgo/go/math/big/arith_decl_pure.go
+++ b/libgo/go/math/big/arith_decl_pure.go
@@ -49,7 +49,3 @@
 func divWVW(z []Word, xn Word, x []Word, y Word) (r Word) {
 	return divWVW_g(z, xn, x, y)
 }
-
-func bitLen(x Word) (n int) {
-	return bitLen_g(x)
-}
diff --git a/libgo/go/math/big/arith_s390x_test.go b/libgo/go/math/big/arith_s390x_test.go
index ee127a4..0e8ac85 100644
--- a/libgo/go/math/big/arith_s390x_test.go
+++ b/libgo/go/math/big/arith_s390x_test.go
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build ignore
-// +build s390x !math_big_pure_go
+// +build s390x,!math_big_pure_go
 
 package big
 
diff --git a/libgo/go/math/big/arith_test.go b/libgo/go/math/big/arith_test.go
index f2b3083..13b0436 100644
--- a/libgo/go/math/big/arith_test.go
+++ b/libgo/go/math/big/arith_test.go
@@ -395,32 +395,3 @@
 		})
 	}
 }
-
-func testWordBitLen(t *testing.T, fname string, f func(Word) int) {
-	for i := 0; i <= _W; i++ {
-		x := Word(1) << uint(i-1) // i == 0 => x == 0
-		n := f(x)
-		if n != i {
-			t.Errorf("got %d; want %d for %s(%#x)", n, i, fname, x)
-		}
-	}
-}
-
-func TestWordBitLen(t *testing.T) {
-	testWordBitLen(t, "bitLen", bitLen)
-	testWordBitLen(t, "bitLen_g", bitLen_g)
-}
-
-// runs b.N iterations of bitLen called on a Word containing (1 << nbits)-1.
-func BenchmarkBitLen(b *testing.B) {
-	// Individual bitLen tests. Numbers chosen to examine both sides
-	// of powers-of-two boundaries.
-	for _, nbits := range []uint{0, 1, 2, 3, 4, 5, 8, 9, 16, 17, 31} {
-		testword := Word((uint64(1) << nbits) - 1)
-		b.Run(fmt.Sprint(nbits), func(b *testing.B) {
-			for i := 0; i < b.N; i++ {
-				bitLen(testword)
-			}
-		})
-	}
-}
diff --git a/libgo/go/math/big/float.go b/libgo/go/math/big/float.go
index aabd7b4..7e11f1a 100644
--- a/libgo/go/math/big/float.go
+++ b/libgo/go/math/big/float.go
@@ -14,6 +14,7 @@
 import (
 	"fmt"
 	"math"
+	"math/bits"
 )
 
 const debugFloat = false // enable for debugging
@@ -97,7 +98,7 @@
 // the slice may (but doesn't have to) be shorter if the mantissa contains
 // trailing 0 bits. x.mant is normalized if the msb of x.mant == 1 (i.e.,
 // the msb is shifted all the way "to the left"). Thus, if the mantissa has
-// trailing 0 bits or x.prec is not a multiple of the the Word size _W,
+// trailing 0 bits or x.prec is not a multiple of the Word size _W,
 // x.mant[0] has trailing zero bits. The msb of the mantissa corresponds
 // to the value 0.5; the exponent x.exp shifts the binary point as needed.
 //
@@ -498,8 +499,8 @@
 	}
 	// x != 0
 	z.form = finite
-	s := nlz64(x)
-	z.mant = z.mant.setUint64(x << s)
+	s := bits.LeadingZeros64(x)
+	z.mant = z.mant.setUint64(x << uint(s))
 	z.exp = int32(64 - s) // always fits
 	if z.prec < 64 {
 		z.round(0)
@@ -1438,8 +1439,16 @@
 
 	if x.form == finite && y.form == finite {
 		// x + y (common case)
+
+		// Below we set z.neg = x.neg, and when z aliases y this will
+		// change the y operand's sign. This is fine, because if an
+		// operand aliases the receiver it'll be overwritten, but we still
+		// want the original x.neg and y.neg values when we evaluate
+		// x.neg != y.neg, so we need to save y.neg before setting z.neg.
+		yneg := y.neg
+
 		z.neg = x.neg
-		if x.neg == y.neg {
+		if x.neg == yneg {
 			// x + y == x + y
 			// (-x) + (-y) == -(x + y)
 			z.uadd(x, y)
@@ -1501,8 +1510,9 @@
 
 	if x.form == finite && y.form == finite {
 		// x - y (common case)
+		yneg := y.neg
 		z.neg = x.neg
-		if x.neg != y.neg {
+		if x.neg != yneg {
 			// x - (-y) == x + y
 			// (-x) - y == -(x + y)
 			z.uadd(x, y)
diff --git a/libgo/go/math/big/float_test.go b/libgo/go/math/big/float_test.go
index 7d4bd31..5fd49bb 100644
--- a/libgo/go/math/big/float_test.go
+++ b/libgo/go/math/big/float_test.go
@@ -1325,6 +1325,34 @@
 	}
 }
 
+func TestIssue20490(t *testing.T) {
+	var tests = []struct {
+		a, b float64
+	}{
+		{4, 1},
+		{-4, 1},
+		{4, -1},
+		{-4, -1},
+	}
+
+	for _, test := range tests {
+		a, b := NewFloat(test.a), NewFloat(test.b)
+		diff := new(Float).Sub(a, b)
+		b.Sub(a, b)
+		if b.Cmp(diff) != 0 {
+			t.Errorf("got %g - %g = %g; want %g\n", a, NewFloat(test.b), b, diff)
+		}
+
+		b = NewFloat(test.b)
+		sum := new(Float).Add(a, b)
+		b.Add(a, b)
+		if b.Cmp(sum) != 0 {
+			t.Errorf("got %g + %g = %g; want %g\n", a, NewFloat(test.b), b, sum)
+		}
+
+	}
+}
+
 // TestFloatMul tests Float.Mul/Quo by comparing the result of a "manual"
 // multiplication/division of arguments represented by Bits values with the
 // respective Float multiplication/division for a variety of precisions
diff --git a/libgo/go/math/big/floatconv_test.go b/libgo/go/math/big/floatconv_test.go
index edcb2eb..6d0f17d 100644
--- a/libgo/go/math/big/floatconv_test.go
+++ b/libgo/go/math/big/floatconv_test.go
@@ -8,10 +8,13 @@
 	"bytes"
 	"fmt"
 	"math"
+	"math/bits"
 	"strconv"
 	"testing"
 )
 
+var zero_ float64
+
 func TestFloatSetFloat64String(t *testing.T) {
 	inf := math.Inf(0)
 	nan := math.NaN()
@@ -22,7 +25,7 @@
 	}{
 		// basics
 		{"0", 0},
-		{"-0", -0},
+		{"-0", -zero_},
 		{"+0", 0},
 		{"1", 1},
 		{"-1", -1},
@@ -36,10 +39,10 @@
 
 		// various zeros
 		{"0e100", 0},
-		{"-0e+100", 0},
+		{"-0e+100", -zero_},
 		{"+0e-100", 0},
 		{"0E100", 0},
-		{"-0E+100", 0},
+		{"-0E+100", -zero_},
 		{"+0E-100", 0},
 
 		// various decimal exponent formats
@@ -78,7 +81,7 @@
 
 		// decimal mantissa, binary exponent
 		{"0p0", 0},
-		{"-0p0", -0},
+		{"-0p0", -zero_},
 		{"1p10", 1 << 10},
 		{"1p+10", 1 << 10},
 		{"+1p-10", 1.0 / (1 << 10)},
@@ -88,9 +91,9 @@
 
 		// binary mantissa, decimal exponent
 		{"0b0", 0},
-		{"-0b0", -0},
+		{"-0b0", -zero_},
 		{"0b0e+10", 0},
-		{"-0b0e-10", -0},
+		{"-0b0e-10", -zero_},
 		{"0b1010", 10},
 		{"0B1010E2", 1000},
 		{"0b.1", 0.5},
@@ -99,7 +102,7 @@
 
 		// binary mantissa, binary exponent
 		{"0b0p+10", 0},
-		{"-0b0p-10", -0},
+		{"-0b0p-10", -zero_},
 		{"0b.1010p4", 10},
 		{"0b1p-1", 0.5},
 		{"0b001p-3", 0.125},
@@ -108,9 +111,9 @@
 
 		// hexadecimal mantissa and exponent
 		{"0x0", 0},
-		{"-0x0", -0},
+		{"-0x0", -zero_},
 		{"0x0p+10", 0},
-		{"-0x0p-10", -0},
+		{"-0x0p-10", -zero_},
 		{"0xff", 255},
 		{"0X.8p1", 1},
 		{"-0X0.00008p16", -0.5},
@@ -134,8 +137,8 @@
 		}
 		f, _ := x.Float64()
 		want := new(Float).SetFloat64(test.x)
-		if x.Cmp(want) != 0 {
-			t.Errorf("%s: got %s (%v); want %v", test.s, &x, f, test.x)
+		if x.Cmp(want) != 0 || x.Signbit() != want.Signbit() {
+			t.Errorf("%s: got %v (%v); want %v", test.s, &x, f, test.x)
 		}
 	}
 }
@@ -326,9 +329,9 @@
 
 // actualPrec returns the number of actually used mantissa bits.
 func actualPrec(x float64) uint {
-	if bits := math.Float64bits(x); x != 0 && bits&(0x7ff<<52) == 0 {
+	if mant := math.Float64bits(x); x != 0 && mant&(0x7ff<<52) == 0 {
 		// x is denormalized
-		return 64 - nlz64(bits&(1<<52-1))
+		return 64 - uint(bits.LeadingZeros64(mant&(1<<52-1)))
 	}
 	return 53
 }
diff --git a/libgo/go/math/big/int.go b/libgo/go/math/big/int.go
index 1d8dabc..62f7fc5 100644
--- a/libgo/go/math/big/int.go
+++ b/libgo/go/math/big/int.go
@@ -324,22 +324,22 @@
 	return
 }
 
-// low32 returns the least significant 32 bits of z.
-func low32(z nat) uint32 {
-	if len(z) == 0 {
+// low32 returns the least significant 32 bits of x.
+func low32(x nat) uint32 {
+	if len(x) == 0 {
 		return 0
 	}
-	return uint32(z[0])
+	return uint32(x[0])
 }
 
-// low64 returns the least significant 64 bits of z.
-func low64(z nat) uint64 {
-	if len(z) == 0 {
+// low64 returns the least significant 64 bits of x.
+func low64(x nat) uint64 {
+	if len(x) == 0 {
 		return 0
 	}
-	v := uint64(z[0])
-	if _W == 32 && len(z) > 1 {
-		v |= uint64(z[1]) << 32
+	v := uint64(x[0])
+	if _W == 32 && len(x) > 1 {
+		return uint64(x[1])<<32 | v
 	}
 	return v
 }
@@ -360,6 +360,20 @@
 	return low64(x.abs)
 }
 
+// IsInt64 reports whether x can be represented as an int64.
+func (x *Int) IsInt64() bool {
+	if len(x.abs) <= 64/_W {
+		w := int64(low64(x.abs))
+		return w >= 0 || x.neg && w == -w
+	}
+	return false
+}
+
+// IsUint64 reports whether x can be represented as a uint64.
+func (x *Int) IsUint64() bool {
+	return !x.neg && len(x.abs) <= 64/_W
+}
+
 // SetString sets z to the value of s, interpreted in the given base,
 // and returns z and a boolean indicating success. The entire string
 // (not just a prefix) must be valid for success. If SetString fails,
@@ -556,7 +570,7 @@
 // Rand sets z to a pseudo-random number in [0, n) and returns z.
 func (z *Int) Rand(rnd *rand.Rand, n *Int) *Int {
 	z.neg = false
-	if n.neg == true || len(n.abs) == 0 {
+	if n.neg || len(n.abs) == 0 {
 		z.abs = nil
 		return z
 	}
diff --git a/libgo/go/math/big/int_test.go b/libgo/go/math/big/int_test.go
index b8e0778..42e810b 100644
--- a/libgo/go/math/big/int_test.go
+++ b/libgo/go/math/big/int_test.go
@@ -7,8 +7,8 @@
 import (
 	"bytes"
 	"encoding/hex"
-	"fmt"
 	"math/rand"
+	"strconv"
 	"strings"
 	"testing"
 	"testing/quick"
@@ -260,7 +260,7 @@
 var divisionSignsTests = []struct {
 	x, y int64
 	q, r int64 // T-division
-	d, m int64 // Euclidian division
+	d, m int64 // Euclidean division
 }{
 	{5, 3, 1, 2, 1, 2},
 	{-5, 3, -1, -2, -2, 1},
@@ -903,56 +903,105 @@
 	}
 }
 
-var int64Tests = []int64{
-	0,
-	1,
-	-1,
-	4294967295,
-	-4294967295,
-	4294967296,
-	-4294967296,
-	9223372036854775807,
-	-9223372036854775807,
-	-9223372036854775808,
+var int64Tests = []string{
+	// int64
+	"0",
+	"1",
+	"-1",
+	"4294967295",
+	"-4294967295",
+	"4294967296",
+	"-4294967296",
+	"9223372036854775807",
+	"-9223372036854775807",
+	"-9223372036854775808",
+
+	// not int64
+	"0x8000000000000000",
+	"-0x8000000000000001",
+	"38579843757496759476987459679745",
+	"-38579843757496759476987459679745",
 }
 
 func TestInt64(t *testing.T) {
-	for i, testVal := range int64Tests {
-		in := NewInt(testVal)
-		out := in.Int64()
+	for _, s := range int64Tests {
+		var x Int
+		_, ok := x.SetString(s, 0)
+		if !ok {
+			t.Errorf("SetString(%s, 0) failed", s)
+			continue
+		}
 
-		if out != testVal {
-			t.Errorf("#%d got %d want %d", i, out, testVal)
+		want, err := strconv.ParseInt(s, 0, 64)
+		if err != nil {
+			if err.(*strconv.NumError).Err == strconv.ErrRange {
+				if x.IsInt64() {
+					t.Errorf("IsInt64(%s) succeeded unexpectedly", s)
+				}
+			} else {
+				t.Errorf("ParseInt(%s) failed", s)
+			}
+			continue
+		}
+
+		if !x.IsInt64() {
+			t.Errorf("IsInt64(%s) failed unexpectedly", s)
+		}
+
+		got := x.Int64()
+		if got != want {
+			t.Errorf("Int64(%s) = %d; want %d", s, got, want)
 		}
 	}
 }
 
-var uint64Tests = []uint64{
-	0,
-	1,
-	4294967295,
-	4294967296,
-	8589934591,
-	8589934592,
-	9223372036854775807,
-	9223372036854775808,
-	18446744073709551615, // 1<<64 - 1
+var uint64Tests = []string{
+	// uint64
+	"0",
+	"1",
+	"4294967295",
+	"4294967296",
+	"8589934591",
+	"8589934592",
+	"9223372036854775807",
+	"9223372036854775808",
+	"0x08000000000000000",
+
+	// not uint64
+	"0x10000000000000000",
+	"-0x08000000000000000",
+	"-1",
 }
 
 func TestUint64(t *testing.T) {
-	in := new(Int)
-	for i, testVal := range uint64Tests {
-		in.SetUint64(testVal)
-		out := in.Uint64()
-
-		if out != testVal {
-			t.Errorf("#%d got %d want %d", i, out, testVal)
+	for _, s := range uint64Tests {
+		var x Int
+		_, ok := x.SetString(s, 0)
+		if !ok {
+			t.Errorf("SetString(%s, 0) failed", s)
+			continue
 		}
 
-		str := fmt.Sprint(testVal)
-		strOut := in.String()
-		if strOut != str {
-			t.Errorf("#%d.String got %s want %s", i, strOut, str)
+		want, err := strconv.ParseUint(s, 0, 64)
+		if err != nil {
+			// check for sign explicitly (ErrRange doesn't cover signed input)
+			if s[0] == '-' || err.(*strconv.NumError).Err == strconv.ErrRange {
+				if x.IsUint64() {
+					t.Errorf("IsUint64(%s) succeeded unexpectedly", s)
+				}
+			} else {
+				t.Errorf("ParseUint(%s) failed", s)
+			}
+			continue
+		}
+
+		if !x.IsUint64() {
+			t.Errorf("IsUint64(%s) failed unexpectedly", s)
+		}
+
+		got := x.Uint64()
+		if got != want {
+			t.Errorf("Uint64(%s) = %d; want %d", s, got, want)
 		}
 	}
 }
diff --git a/libgo/go/math/big/nat.go b/libgo/go/math/big/nat.go
index 9b1a626..889eacb 100644
--- a/libgo/go/math/big/nat.go
+++ b/libgo/go/math/big/nat.go
@@ -9,6 +9,7 @@
 package big
 
 import (
+	"math/bits"
 	"math/rand"
 	"sync"
 )
@@ -67,24 +68,14 @@
 }
 
 func (z nat) setUint64(x uint64) nat {
-	// single-digit values
+	// single-word value
 	if w := Word(x); uint64(w) == x {
 		return z.setWord(w)
 	}
-
-	// compute number of words n required to represent x
-	n := 0
-	for t := x; t > 0; t >>= _W {
-		n++
-	}
-
-	// split x into n words
-	z = z.make(n)
-	for i := range z {
-		z[i] = Word(x & _M)
-		x >>= _W
-	}
-
+	// 2-word value
+	z = z.make(2)
+	z[1] = Word(x >> 32)
+	z[0] = Word(x)
 	return z
 }
 
@@ -653,49 +644,11 @@
 // Length of x in bits. x must be normalized.
 func (x nat) bitLen() int {
 	if i := len(x) - 1; i >= 0 {
-		return i*_W + bitLen(x[i])
+		return i*_W + bits.Len(uint(x[i]))
 	}
 	return 0
 }
 
-const deBruijn32 = 0x077CB531
-
-var deBruijn32Lookup = [...]byte{
-	0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8,
-	31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9,
-}
-
-const deBruijn64 = 0x03f79d71b4ca8b09
-
-var deBruijn64Lookup = [...]byte{
-	0, 1, 56, 2, 57, 49, 28, 3, 61, 58, 42, 50, 38, 29, 17, 4,
-	62, 47, 59, 36, 45, 43, 51, 22, 53, 39, 33, 30, 24, 18, 12, 5,
-	63, 55, 48, 27, 60, 41, 37, 16, 46, 35, 44, 21, 52, 32, 23, 11,
-	54, 26, 40, 15, 34, 20, 31, 10, 25, 14, 19, 9, 13, 8, 7, 6,
-}
-
-// trailingZeroBits returns the number of consecutive least significant zero
-// bits of x.
-func trailingZeroBits(x Word) uint {
-	// x & -x leaves only the right-most bit set in the word. Let k be the
-	// index of that bit. Since only a single bit is set, the value is two
-	// to the power of k. Multiplying by a power of two is equivalent to
-	// left shifting, in this case by k bits. The de Bruijn constant is
-	// such that all six bit, consecutive substrings are distinct.
-	// Therefore, if we have a left shifted version of this constant we can
-	// find by how many bits it was shifted by looking at which six bit
-	// substring ended up at the top of the word.
-	// (Knuth, volume 4, section 7.3.1)
-	switch _W {
-	case 32:
-		return uint(deBruijn32Lookup[((x&-x)*deBruijn32)>>27])
-	case 64:
-		return uint(deBruijn64Lookup[((x&-x)*(deBruijn64&_M))>>58])
-	default:
-		panic("unknown word size")
-	}
-}
-
 // trailingZeroBits returns the number of consecutive least significant zero
 // bits of x.
 func (x nat) trailingZeroBits() uint {
@@ -707,7 +660,7 @@
 		i++
 	}
 	// x[i] != 0
-	return i*_W + trailingZeroBits(x[i])
+	return i*_W + uint(bits.TrailingZeros(uint(x[i])))
 }
 
 // z = x << s
diff --git a/libgo/go/math/big/nat_test.go b/libgo/go/math/big/nat_test.go
index ebb2985..200a247 100644
--- a/libgo/go/math/big/nat_test.go
+++ b/libgo/go/math/big/nat_test.go
@@ -303,36 +303,6 @@
 	}
 }
 
-func TestTrailingZeroBits(t *testing.T) {
-	// test 0 case explicitly
-	if n := trailingZeroBits(0); n != 0 {
-		t.Errorf("got trailingZeroBits(0) = %d; want 0", n)
-	}
-
-	x := Word(1)
-	for i := uint(0); i < _W; i++ {
-		n := trailingZeroBits(x)
-		if n != i {
-			t.Errorf("got trailingZeroBits(%#x) = %d; want %d", x, n, i%_W)
-		}
-		x <<= 1
-	}
-
-	// test 0 case explicitly
-	if n := nat(nil).trailingZeroBits(); n != 0 {
-		t.Errorf("got nat(nil).trailingZeroBits() = %d; want 0", n)
-	}
-
-	y := nat(nil).set(natOne)
-	for i := uint(0); i <= 3*_W; i++ {
-		n := y.trailingZeroBits()
-		if n != i {
-			t.Errorf("got 0x%s.trailingZeroBits() = %d; want %d", y.utoa(16), n, i)
-		}
-		y = y.shl(y, 1)
-	}
-}
-
 var montgomeryTests = []struct {
 	x, y, m      string
 	k0           uint64
diff --git a/libgo/go/math/big/natconv.go b/libgo/go/math/big/natconv.go
index 4454784..25a345e 100644
--- a/libgo/go/math/big/natconv.go
+++ b/libgo/go/math/big/natconv.go
@@ -11,6 +11,7 @@
 	"fmt"
 	"io"
 	"math"
+	"math/bits"
 	"sync"
 )
 
@@ -262,7 +263,7 @@
 	// convert power of two and non power of two bases separately
 	if b := Word(base); b == b&-b {
 		// shift is base b digit size in bits
-		shift := trailingZeroBits(b) // shift > 0 because b >= 2
+		shift := uint(bits.TrailingZeros(uint(b))) // shift > 0 because b >= 2
 		mask := Word(1<<shift - 1)
 		w := x[0]         // current word
 		nbits := uint(_W) // number of unprocessed bits in w
diff --git a/libgo/go/math/big/natconv_test.go b/libgo/go/math/big/natconv_test.go
index bdb60e6..898a39f 100644
--- a/libgo/go/math/big/natconv_test.go
+++ b/libgo/go/math/big/natconv_test.go
@@ -8,10 +8,18 @@
 	"bytes"
 	"fmt"
 	"io"
+	"math/bits"
 	"strings"
 	"testing"
 )
 
+// log2 computes the integer binary logarithm of x.
+// The result is the integer n for which 2^n <= x < 2^(n+1).
+// If x == 0, the result is -1.
+func log2(x Word) int {
+	return bits.Len(uint(x)) - 1
+}
+
 func itoa(x nat, base int) []byte {
 	// special cases
 	switch {
diff --git a/libgo/go/math/big/prime_test.go b/libgo/go/math/big/prime_test.go
index a2d3d18..7760519 100644
--- a/libgo/go/math/big/prime_test.go
+++ b/libgo/go/math/big/prime_test.go
@@ -200,7 +200,7 @@
 		n[0] = Word(i)
 		pseudo := cond(n)
 		if pseudo && (len(want) == 0 || i != want[0]) {
-			t.Errorf("%s(%v, base=2) = %v, want false", name, i)
+			t.Errorf("%s(%v, base=2) = true, want false", name, i)
 		} else if !pseudo && len(want) >= 1 && i == want[0] {
 			t.Errorf("%s(%v, base=2) = false, want true", name, i)
 		}
diff --git a/libgo/go/math/big/ratconv.go b/libgo/go/math/big/ratconv.go
index a6a401c..4bc6ef7 100644
--- a/libgo/go/math/big/ratconv.go
+++ b/libgo/go/math/big/ratconv.go
@@ -40,8 +40,8 @@
 // SetString sets z to the value of s and returns z and a boolean indicating
 // success. s can be given as a fraction "a/b" or as a floating-point number
 // optionally followed by an exponent. The entire string (not just a prefix)
-// must be valid for success. If the operation failed, the value of z is un-
-// defined but the returned value is nil.
+// must be valid for success. If the operation failed, the value of z is
+// undefined but the returned value is nil.
 func (z *Rat) SetString(s string) (*Rat, bool) {
 	if len(s) == 0 {
 		return nil, false
diff --git a/libgo/go/math/bits/bits.go b/libgo/go/math/bits/bits.go
new file mode 100644
index 0000000..989baac
--- /dev/null
+++ b/libgo/go/math/bits/bits.go
@@ -0,0 +1,330 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run make_tables.go
+
+// Package bits implements bit counting and manipulation
+// functions for the predeclared unsigned integer types.
+package bits
+
+const uintSize = 32 << (^uint(0) >> 32 & 1) // 32 or 64
+
+// UintSize is the size of a uint in bits.
+const UintSize = uintSize
+
+// --- LeadingZeros ---
+
+// LeadingZeros returns the number of leading zero bits in x; the result is UintSize for x == 0.
+func LeadingZeros(x uint) int { return UintSize - Len(x) }
+
+// LeadingZeros8 returns the number of leading zero bits in x; the result is 8 for x == 0.
+func LeadingZeros8(x uint8) int { return 8 - Len8(x) }
+
+// LeadingZeros16 returns the number of leading zero bits in x; the result is 16 for x == 0.
+func LeadingZeros16(x uint16) int { return 16 - Len16(x) }
+
+// LeadingZeros32 returns the number of leading zero bits in x; the result is 32 for x == 0.
+func LeadingZeros32(x uint32) int { return 32 - Len32(x) }
+
+// LeadingZeros64 returns the number of leading zero bits in x; the result is 64 for x == 0.
+func LeadingZeros64(x uint64) int { return 64 - Len64(x) }
+
+// --- TrailingZeros ---
+
+// See http://supertech.csail.mit.edu/papers/debruijn.pdf
+const deBruijn32 = 0x077CB531
+
+var deBruijn32tab = [32]byte{
+	0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8,
+	31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9,
+}
+
+const deBruijn64 = 0x03f79d71b4ca8b09
+
+var deBruijn64tab = [64]byte{
+	0, 1, 56, 2, 57, 49, 28, 3, 61, 58, 42, 50, 38, 29, 17, 4,
+	62, 47, 59, 36, 45, 43, 51, 22, 53, 39, 33, 30, 24, 18, 12, 5,
+	63, 55, 48, 27, 60, 41, 37, 16, 46, 35, 44, 21, 52, 32, 23, 11,
+	54, 26, 40, 15, 34, 20, 31, 10, 25, 14, 19, 9, 13, 8, 7, 6,
+}
+
+// TrailingZeros returns the number of trailing zero bits in x; the result is UintSize for x == 0.
+func TrailingZeros(x uint) int {
+	if UintSize == 32 {
+		return TrailingZeros32(uint32(x))
+	}
+	return TrailingZeros64(uint64(x))
+}
+
+// TrailingZeros8 returns the number of trailing zero bits in x; the result is 8 for x == 0.
+func TrailingZeros8(x uint8) int {
+	return int(ntz8tab[x])
+}
+
+// TrailingZeros16 returns the number of trailing zero bits in x; the result is 16 for x == 0.
+func TrailingZeros16(x uint16) (n int) {
+	if x == 0 {
+		return 16
+	}
+	// see comment in TrailingZeros64
+	return int(deBruijn32tab[uint32(x&-x)*deBruijn32>>(32-5)])
+}
+
+// TrailingZeros32 returns the number of trailing zero bits in x; the result is 32 for x == 0.
+func TrailingZeros32(x uint32) int {
+	if x == 0 {
+		return 32
+	}
+	// see comment in TrailingZeros64
+	return int(deBruijn32tab[(x&-x)*deBruijn32>>(32-5)])
+}
+
+// TrailingZeros64 returns the number of trailing zero bits in x; the result is 64 for x == 0.
+func TrailingZeros64(x uint64) int {
+	if x == 0 {
+		return 64
+	}
+	// If popcount is fast, replace code below with return popcount(^x & (x - 1)).
+	//
+	// x & -x leaves only the right-most bit set in the word. Let k be the
+	// index of that bit. Since only a single bit is set, the value is two
+	// to the power of k. Multiplying by a power of two is equivalent to
+	// left shifting, in this case by k bits. The de Bruijn (64 bit) constant
+	// is such that all six bit, consecutive substrings are distinct.
+	// Therefore, if we have a left shifted version of this constant we can
+	// find by how many bits it was shifted by looking at which six bit
+	// substring ended up at the top of the word.
+	// (Knuth, volume 4, section 7.3.1)
+	return int(deBruijn64tab[(x&-x)*deBruijn64>>(64-6)])
+}
+
+// --- OnesCount ---
+
+const m0 = 0x5555555555555555 // 01010101 ...
+const m1 = 0x3333333333333333 // 00110011 ...
+const m2 = 0x0f0f0f0f0f0f0f0f // 00001111 ...
+const m3 = 0x00ff00ff00ff00ff // etc.
+const m4 = 0x0000ffff0000ffff
+
+// OnesCount returns the number of one bits ("population count") in x.
+func OnesCount(x uint) int {
+	if UintSize == 32 {
+		return OnesCount32(uint32(x))
+	}
+	return OnesCount64(uint64(x))
+}
+
+// OnesCount8 returns the number of one bits ("population count") in x.
+func OnesCount8(x uint8) int {
+	return int(pop8tab[x])
+}
+
+// OnesCount16 returns the number of one bits ("population count") in x.
+func OnesCount16(x uint16) int {
+	return int(pop8tab[x>>8] + pop8tab[x&0xff])
+}
+
+// OnesCount32 returns the number of one bits ("population count") in x.
+func OnesCount32(x uint32) int {
+	return int(pop8tab[x>>24] + pop8tab[x>>16&0xff] + pop8tab[x>>8&0xff] + pop8tab[x&0xff])
+}
+
+// OnesCount64 returns the number of one bits ("population count") in x.
+func OnesCount64(x uint64) int {
+	// Implementation: Parallel summing of adjacent bits.
+	// See "Hacker's Delight", Chap. 5: Counting Bits.
+	// The following pattern shows the general approach:
+	//
+	//   x = x>>1&(m0&m) + x&(m0&m)
+	//   x = x>>2&(m1&m) + x&(m1&m)
+	//   x = x>>4&(m2&m) + x&(m2&m)
+	//   x = x>>8&(m3&m) + x&(m3&m)
+	//   x = x>>16&(m4&m) + x&(m4&m)
+	//   x = x>>32&(m5&m) + x&(m5&m)
+	//   return int(x)
+	//
+	// Masking (& operations) can be left away when there's no
+	// danger that a field's sum will carry over into the next
+	// field: Since the result cannot be > 64, 8 bits is enough
+	// and we can ignore the masks for the shifts by 8 and up.
+	// Per "Hacker's Delight", the first line can be simplified
+	// more, but it saves at best one instruction, so we leave
+	// it alone for clarity.
+	const m = 1<<64 - 1
+	x = x>>1&(m0&m) + x&(m0&m)
+	x = x>>2&(m1&m) + x&(m1&m)
+	x = (x>>4 + x) & (m2 & m)
+	x += x >> 8
+	x += x >> 16
+	x += x >> 32
+	return int(x) & (1<<7 - 1)
+}
+
+// --- RotateLeft ---
+
+// RotateLeft returns the value of x rotated left by (k mod UintSize) bits.
+// To rotate x right by k bits, call RotateLeft(x, -k).
+func RotateLeft(x uint, k int) uint {
+	if UintSize == 32 {
+		return uint(RotateLeft32(uint32(x), k))
+	}
+	return uint(RotateLeft64(uint64(x), k))
+}
+
+// RotateLeft8 returns the value of x rotated left by (k mod 8) bits.
+// To rotate x right by k bits, call RotateLeft8(x, -k).
+func RotateLeft8(x uint8, k int) uint8 {
+	const n = 8
+	s := uint(k) & (n - 1)
+	return x<<s | x>>(n-s)
+}
+
+// RotateLeft16 returns the value of x rotated left by (k mod 16) bits.
+// To rotate x right by k bits, call RotateLeft16(x, -k).
+func RotateLeft16(x uint16, k int) uint16 {
+	const n = 16
+	s := uint(k) & (n - 1)
+	return x<<s | x>>(n-s)
+}
+
+// RotateLeft32 returns the value of x rotated left by (k mod 32) bits.
+// To rotate x right by k bits, call RotateLeft32(x, -k).
+func RotateLeft32(x uint32, k int) uint32 {
+	const n = 32
+	s := uint(k) & (n - 1)
+	return x<<s | x>>(n-s)
+}
+
+// RotateLeft64 returns the value of x rotated left by (k mod 64) bits.
+// To rotate x right by k bits, call RotateLeft64(x, -k).
+func RotateLeft64(x uint64, k int) uint64 {
+	const n = 64
+	s := uint(k) & (n - 1)
+	return x<<s | x>>(n-s)
+}
+
+// --- Reverse ---
+
+// Reverse returns the value of x with its bits in reversed order.
+func Reverse(x uint) uint {
+	if UintSize == 32 {
+		return uint(Reverse32(uint32(x)))
+	}
+	return uint(Reverse64(uint64(x)))
+}
+
+// Reverse8 returns the value of x with its bits in reversed order.
+func Reverse8(x uint8) uint8 {
+	return rev8tab[x]
+}
+
+// Reverse16 returns the value of x with its bits in reversed order.
+func Reverse16(x uint16) uint16 {
+	return uint16(rev8tab[x>>8]) | uint16(rev8tab[x&0xff])<<8
+}
+
+// Reverse32 returns the value of x with its bits in reversed order.
+func Reverse32(x uint32) uint32 {
+	const m = 1<<32 - 1
+	x = x>>1&(m0&m) | x&(m0&m)<<1
+	x = x>>2&(m1&m) | x&(m1&m)<<2
+	x = x>>4&(m2&m) | x&(m2&m)<<4
+	x = x>>8&(m3&m) | x&(m3&m)<<8
+	return x>>16 | x<<16
+}
+
+// Reverse64 returns the value of x with its bits in reversed order.
+func Reverse64(x uint64) uint64 {
+	const m = 1<<64 - 1
+	x = x>>1&(m0&m) | x&(m0&m)<<1
+	x = x>>2&(m1&m) | x&(m1&m)<<2
+	x = x>>4&(m2&m) | x&(m2&m)<<4
+	x = x>>8&(m3&m) | x&(m3&m)<<8
+	x = x>>16&(m4&m) | x&(m4&m)<<16
+	return x>>32 | x<<32
+}
+
+// --- ReverseBytes ---
+
+// ReverseBytes returns the value of x with its bytes in reversed order.
+func ReverseBytes(x uint) uint {
+	if UintSize == 32 {
+		return uint(ReverseBytes32(uint32(x)))
+	}
+	return uint(ReverseBytes64(uint64(x)))
+}
+
+// ReverseBytes16 returns the value of x with its bytes in reversed order.
+func ReverseBytes16(x uint16) uint16 {
+	return x>>8 | x<<8
+}
+
+// ReverseBytes32 returns the value of x with its bytes in reversed order.
+func ReverseBytes32(x uint32) uint32 {
+	const m = 1<<32 - 1
+	x = x>>8&(m3&m) | x&(m3&m)<<8
+	return x>>16 | x<<16
+}
+
+// ReverseBytes64 returns the value of x with its bytes in reversed order.
+func ReverseBytes64(x uint64) uint64 {
+	const m = 1<<64 - 1
+	x = x>>8&(m3&m) | x&(m3&m)<<8
+	x = x>>16&(m4&m) | x&(m4&m)<<16
+	return x>>32 | x<<32
+}
+
+// --- Len ---
+
+// Len returns the minimum number of bits required to represent x; the result is 0 for x == 0.
+func Len(x uint) int {
+	if UintSize == 32 {
+		return Len32(uint32(x))
+	}
+	return Len64(uint64(x))
+}
+
+// Len8 returns the minimum number of bits required to represent x; the result is 0 for x == 0.
+func Len8(x uint8) int {
+	return int(len8tab[x])
+}
+
+// Len16 returns the minimum number of bits required to represent x; the result is 0 for x == 0.
+func Len16(x uint16) (n int) {
+	if x >= 1<<8 {
+		x >>= 8
+		n = 8
+	}
+	return n + int(len8tab[x])
+}
+
+// Len32 returns the minimum number of bits required to represent x; the result is 0 for x == 0.
+func Len32(x uint32) (n int) {
+	if x >= 1<<16 {
+		x >>= 16
+		n = 16
+	}
+	if x >= 1<<8 {
+		x >>= 8
+		n += 8
+	}
+	return n + int(len8tab[x])
+}
+
+// Len64 returns the minimum number of bits required to represent x; the result is 0 for x == 0.
+func Len64(x uint64) (n int) {
+	if x >= 1<<32 {
+		x >>= 32
+		n = 32
+	}
+	if x >= 1<<16 {
+		x >>= 16
+		n += 16
+	}
+	if x >= 1<<8 {
+		x >>= 8
+		n += 8
+	}
+	return n + int(len8tab[x])
+}
diff --git a/libgo/go/math/bits/bits_tables.go b/libgo/go/math/bits/bits_tables.go
new file mode 100644
index 0000000..f1e15a0
--- /dev/null
+++ b/libgo/go/math/bits/bits_tables.go
@@ -0,0 +1,83 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by go run make_tables.go. DO NOT EDIT.
+
+package bits
+
+var ntz8tab = [256]uint8{
+	0x08, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x05, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x06, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x05, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x07, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x05, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x06, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x05, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+	0x04, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00,
+}
+
+var pop8tab = [256]uint8{
+	0x00, 0x01, 0x01, 0x02, 0x01, 0x02, 0x02, 0x03, 0x01, 0x02, 0x02, 0x03, 0x02, 0x03, 0x03, 0x04,
+	0x01, 0x02, 0x02, 0x03, 0x02, 0x03, 0x03, 0x04, 0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05,
+	0x01, 0x02, 0x02, 0x03, 0x02, 0x03, 0x03, 0x04, 0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05,
+	0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05, 0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06,
+	0x01, 0x02, 0x02, 0x03, 0x02, 0x03, 0x03, 0x04, 0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05,
+	0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05, 0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06,
+	0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05, 0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06,
+	0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x06, 0x05, 0x06, 0x06, 0x07,
+	0x01, 0x02, 0x02, 0x03, 0x02, 0x03, 0x03, 0x04, 0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05,
+	0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05, 0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06,
+	0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05, 0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06,
+	0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x06, 0x05, 0x06, 0x06, 0x07,
+	0x02, 0x03, 0x03, 0x04, 0x03, 0x04, 0x04, 0x05, 0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06,
+	0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x06, 0x05, 0x06, 0x06, 0x07,
+	0x03, 0x04, 0x04, 0x05, 0x04, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x06, 0x05, 0x06, 0x06, 0x07,
+	0x04, 0x05, 0x05, 0x06, 0x05, 0x06, 0x06, 0x07, 0x05, 0x06, 0x06, 0x07, 0x06, 0x07, 0x07, 0x08,
+}
+
+var rev8tab = [256]uint8{
+	0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
+	0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
+	0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
+	0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
+	0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
+	0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
+	0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
+	0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
+	0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
+	0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
+	0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
+	0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
+	0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
+	0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
+	0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
+	0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
+}
+
+var len8tab = [256]uint8{
+	0x00, 0x01, 0x02, 0x02, 0x03, 0x03, 0x03, 0x03, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+	0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+	0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+	0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+}
diff --git a/libgo/go/math/bits/bits_test.go b/libgo/go/math/bits/bits_test.go
new file mode 100644
index 0000000..ba05210
--- /dev/null
+++ b/libgo/go/math/bits/bits_test.go
@@ -0,0 +1,747 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bits
+
+import (
+	"testing"
+	"unsafe"
+)
+
+func TestUintSize(t *testing.T) {
+	var x uint
+	if want := unsafe.Sizeof(x) * 8; UintSize != want {
+		t.Fatalf("UintSize = %d; want %d", UintSize, want)
+	}
+}
+
+func TestLeadingZeros(t *testing.T) {
+	for i := 0; i < 256; i++ {
+		nlz := tab[i].nlz
+		for k := 0; k < 64-8; k++ {
+			x := uint64(i) << uint(k)
+			if x <= 1<<8-1 {
+				got := LeadingZeros8(uint8(x))
+				want := nlz - k + (8 - 8)
+				if x == 0 {
+					want = 8
+				}
+				if got != want {
+					t.Fatalf("LeadingZeros8(%#02x) == %d; want %d", x, got, want)
+				}
+			}
+
+			if x <= 1<<16-1 {
+				got := LeadingZeros16(uint16(x))
+				want := nlz - k + (16 - 8)
+				if x == 0 {
+					want = 16
+				}
+				if got != want {
+					t.Fatalf("LeadingZeros16(%#04x) == %d; want %d", x, got, want)
+				}
+			}
+
+			if x <= 1<<32-1 {
+				got := LeadingZeros32(uint32(x))
+				want := nlz - k + (32 - 8)
+				if x == 0 {
+					want = 32
+				}
+				if got != want {
+					t.Fatalf("LeadingZeros32(%#08x) == %d; want %d", x, got, want)
+				}
+				if UintSize == 32 {
+					got = LeadingZeros(uint(x))
+					if got != want {
+						t.Fatalf("LeadingZeros(%#08x) == %d; want %d", x, got, want)
+					}
+				}
+			}
+
+			if x <= 1<<64-1 {
+				got := LeadingZeros64(uint64(x))
+				want := nlz - k + (64 - 8)
+				if x == 0 {
+					want = 64
+				}
+				if got != want {
+					t.Fatalf("LeadingZeros64(%#016x) == %d; want %d", x, got, want)
+				}
+				if UintSize == 64 {
+					got = LeadingZeros(uint(x))
+					if got != want {
+						t.Fatalf("LeadingZeros(%#016x) == %d; want %d", x, got, want)
+					}
+				}
+			}
+		}
+	}
+}
+
+// Exported (global) variable serving as input for some
+// of the benchmarks to ensure side-effect free calls
+// are not optimized away.
+var Input uint64 = deBruijn64
+
+// Exported (global) variable to store function results
+// during benchmarking to ensure side-effect free calls
+// are not optimized away.
+var Output int
+
+func BenchmarkLeadingZeros(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += LeadingZeros(uint(Input) >> (uint(i) % UintSize))
+	}
+	Output = s
+}
+
+func BenchmarkLeadingZeros8(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += LeadingZeros8(uint8(Input) >> (uint(i) % 8))
+	}
+	Output = s
+}
+
+func BenchmarkLeadingZeros16(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += LeadingZeros16(uint16(Input) >> (uint(i) % 16))
+	}
+	Output = s
+}
+
+func BenchmarkLeadingZeros32(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += LeadingZeros32(uint32(Input) >> (uint(i) % 32))
+	}
+	Output = s
+}
+
+func BenchmarkLeadingZeros64(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += LeadingZeros64(uint64(Input) >> (uint(i) % 64))
+	}
+	Output = s
+}
+
+func TestTrailingZeros(t *testing.T) {
+	for i := 0; i < 256; i++ {
+		ntz := tab[i].ntz
+		for k := 0; k < 64-8; k++ {
+			x := uint64(i) << uint(k)
+			want := ntz + k
+			if x <= 1<<8-1 {
+				got := TrailingZeros8(uint8(x))
+				if x == 0 {
+					want = 8
+				}
+				if got != want {
+					t.Fatalf("TrailingZeros8(%#02x) == %d; want %d", x, got, want)
+				}
+			}
+
+			if x <= 1<<16-1 {
+				got := TrailingZeros16(uint16(x))
+				if x == 0 {
+					want = 16
+				}
+				if got != want {
+					t.Fatalf("TrailingZeros16(%#04x) == %d; want %d", x, got, want)
+				}
+			}
+
+			if x <= 1<<32-1 {
+				got := TrailingZeros32(uint32(x))
+				if x == 0 {
+					want = 32
+				}
+				if got != want {
+					t.Fatalf("TrailingZeros32(%#08x) == %d; want %d", x, got, want)
+				}
+				if UintSize == 32 {
+					got = TrailingZeros(uint(x))
+					if got != want {
+						t.Fatalf("TrailingZeros(%#08x) == %d; want %d", x, got, want)
+					}
+				}
+			}
+
+			if x <= 1<<64-1 {
+				got := TrailingZeros64(uint64(x))
+				if x == 0 {
+					want = 64
+				}
+				if got != want {
+					t.Fatalf("TrailingZeros64(%#016x) == %d; want %d", x, got, want)
+				}
+				if UintSize == 64 {
+					got = TrailingZeros(uint(x))
+					if got != want {
+						t.Fatalf("TrailingZeros(%#016x) == %d; want %d", x, got, want)
+					}
+				}
+			}
+		}
+	}
+}
+
+func BenchmarkTrailingZeros(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += TrailingZeros(uint(Input) << (uint(i) % UintSize))
+	}
+	Output = s
+}
+
+func BenchmarkTrailingZeros8(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += TrailingZeros8(uint8(Input) << (uint(i) % 8))
+	}
+	Output = s
+}
+
+func BenchmarkTrailingZeros16(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += TrailingZeros16(uint16(Input) << (uint(i) % 16))
+	}
+	Output = s
+}
+
+func BenchmarkTrailingZeros32(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += TrailingZeros32(uint32(Input) << (uint(i) % 32))
+	}
+	Output = s
+}
+
+func BenchmarkTrailingZeros64(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += TrailingZeros64(uint64(Input) << (uint(i) % 64))
+	}
+	Output = s
+}
+
+func TestOnesCount(t *testing.T) {
+	var x uint64
+	for i := 0; i <= 64; i++ {
+		testOnesCount(t, x, i)
+		x = x<<1 | 1
+	}
+
+	for i := 64; i >= 0; i-- {
+		testOnesCount(t, x, i)
+		x = x << 1
+	}
+
+	for i := 0; i < 256; i++ {
+		for k := 0; k < 64-8; k++ {
+			testOnesCount(t, uint64(i)<<uint(k), tab[i].pop)
+		}
+	}
+}
+
+func testOnesCount(t *testing.T, x uint64, want int) {
+	if x <= 1<<8-1 {
+		got := OnesCount8(uint8(x))
+		if got != want {
+			t.Fatalf("OnesCount8(%#02x) == %d; want %d", uint8(x), got, want)
+		}
+	}
+
+	if x <= 1<<16-1 {
+		got := OnesCount16(uint16(x))
+		if got != want {
+			t.Fatalf("OnesCount16(%#04x) == %d; want %d", uint16(x), got, want)
+		}
+	}
+
+	if x <= 1<<32-1 {
+		got := OnesCount32(uint32(x))
+		if got != want {
+			t.Fatalf("OnesCount32(%#08x) == %d; want %d", uint32(x), got, want)
+		}
+		if UintSize == 32 {
+			got = OnesCount(uint(x))
+			if got != want {
+				t.Fatalf("OnesCount(%#08x) == %d; want %d", uint32(x), got, want)
+			}
+		}
+	}
+
+	if x <= 1<<64-1 {
+		got := OnesCount64(uint64(x))
+		if got != want {
+			t.Fatalf("OnesCount64(%#016x) == %d; want %d", x, got, want)
+		}
+		if UintSize == 64 {
+			got = OnesCount(uint(x))
+			if got != want {
+				t.Fatalf("OnesCount(%#016x) == %d; want %d", x, got, want)
+			}
+		}
+	}
+}
+
+func BenchmarkOnesCount(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += OnesCount(uint(Input))
+	}
+	Output = s
+}
+
+func BenchmarkOnesCount8(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += OnesCount8(uint8(Input))
+	}
+	Output = s
+}
+
+func BenchmarkOnesCount16(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += OnesCount16(uint16(Input))
+	}
+	Output = s
+}
+
+func BenchmarkOnesCount32(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += OnesCount32(uint32(Input))
+	}
+	Output = s
+}
+
+func BenchmarkOnesCount64(b *testing.B) {
+	var s int
+	for i := 0; i < b.N; i++ {
+		s += OnesCount64(uint64(Input))
+	}
+	Output = s
+}
+
+func TestRotateLeft(t *testing.T) {
+	var m uint64 = deBruijn64
+
+	for k := uint(0); k < 128; k++ {
+		x8 := uint8(m)
+		got8 := RotateLeft8(x8, int(k))
+		want8 := x8<<(k&0x7) | x8>>(8-k&0x7)
+		if got8 != want8 {
+			t.Fatalf("RotateLeft8(%#02x, %d) == %#02x; want %#02x", x8, k, got8, want8)
+		}
+		got8 = RotateLeft8(want8, -int(k))
+		if got8 != x8 {
+			t.Fatalf("RotateLeft8(%#02x, -%d) == %#02x; want %#02x", want8, k, got8, x8)
+		}
+
+		x16 := uint16(m)
+		got16 := RotateLeft16(x16, int(k))
+		want16 := x16<<(k&0xf) | x16>>(16-k&0xf)
+		if got16 != want16 {
+			t.Fatalf("RotateLeft16(%#04x, %d) == %#04x; want %#04x", x16, k, got16, want16)
+		}
+		got16 = RotateLeft16(want16, -int(k))
+		if got16 != x16 {
+			t.Fatalf("RotateLeft16(%#04x, -%d) == %#04x; want %#04x", want16, k, got16, x16)
+		}
+
+		x32 := uint32(m)
+		got32 := RotateLeft32(x32, int(k))
+		want32 := x32<<(k&0x1f) | x32>>(32-k&0x1f)
+		if got32 != want32 {
+			t.Fatalf("RotateLeft32(%#08x, %d) == %#08x; want %#08x", x32, k, got32, want32)
+		}
+		got32 = RotateLeft32(want32, -int(k))
+		if got32 != x32 {
+			t.Fatalf("RotateLeft32(%#08x, -%d) == %#08x; want %#08x", want32, k, got32, x32)
+		}
+		if UintSize == 32 {
+			x := uint(m)
+			got := RotateLeft(x, int(k))
+			want := x<<(k&0x1f) | x>>(32-k&0x1f)
+			if got != want {
+				t.Fatalf("RotateLeft(%#08x, %d) == %#08x; want %#08x", x, k, got, want)
+			}
+			got = RotateLeft(want, -int(k))
+			if got != x {
+				t.Fatalf("RotateLeft(%#08x, -%d) == %#08x; want %#08x", want, k, got, x)
+			}
+		}
+
+		x64 := uint64(m)
+		got64 := RotateLeft64(x64, int(k))
+		want64 := x64<<(k&0x3f) | x64>>(64-k&0x3f)
+		if got64 != want64 {
+			t.Fatalf("RotateLeft64(%#016x, %d) == %#016x; want %#016x", x64, k, got64, want64)
+		}
+		got64 = RotateLeft64(want64, -int(k))
+		if got64 != x64 {
+			t.Fatalf("RotateLeft64(%#016x, -%d) == %#016x; want %#016x", want64, k, got64, x64)
+		}
+		if UintSize == 64 {
+			x := uint(m)
+			got := RotateLeft(x, int(k))
+			want := x<<(k&0x3f) | x>>(64-k&0x3f)
+			if got != want {
+				t.Fatalf("RotateLeft(%#016x, %d) == %#016x; want %#016x", x, k, got, want)
+			}
+			got = RotateLeft(want, -int(k))
+			if got != x {
+				t.Fatalf("RotateLeft(%#08x, -%d) == %#08x; want %#08x", want, k, got, x)
+			}
+		}
+	}
+}
+
+func BenchmarkRotateLeft(b *testing.B) {
+	var s uint
+	for i := 0; i < b.N; i++ {
+		s += RotateLeft(uint(Input), i)
+	}
+	Output = int(s)
+}
+
+func BenchmarkRotateLeft8(b *testing.B) {
+	var s uint8
+	for i := 0; i < b.N; i++ {
+		s += RotateLeft8(uint8(Input), i)
+	}
+	Output = int(s)
+}
+
+func BenchmarkRotateLeft16(b *testing.B) {
+	var s uint16
+	for i := 0; i < b.N; i++ {
+		s += RotateLeft16(uint16(Input), i)
+	}
+	Output = int(s)
+}
+
+func BenchmarkRotateLeft32(b *testing.B) {
+	var s uint32
+	for i := 0; i < b.N; i++ {
+		s += RotateLeft32(uint32(Input), i)
+	}
+	Output = int(s)
+}
+
+func BenchmarkRotateLeft64(b *testing.B) {
+	var s uint64
+	for i := 0; i < b.N; i++ {
+		s += RotateLeft64(uint64(Input), i)
+	}
+	Output = int(s)
+}
+
+func TestReverse(t *testing.T) {
+	// test each bit
+	for i := uint(0); i < 64; i++ {
+		testReverse(t, uint64(1)<<i, uint64(1)<<(63-i))
+	}
+
+	// test a few patterns
+	for _, test := range []struct {
+		x, r uint64
+	}{
+		{0, 0},
+		{0x1, 0x8 << 60},
+		{0x2, 0x4 << 60},
+		{0x3, 0xc << 60},
+		{0x4, 0x2 << 60},
+		{0x5, 0xa << 60},
+		{0x6, 0x6 << 60},
+		{0x7, 0xe << 60},
+		{0x8, 0x1 << 60},
+		{0x9, 0x9 << 60},
+		{0xa, 0x5 << 60},
+		{0xb, 0xd << 60},
+		{0xc, 0x3 << 60},
+		{0xd, 0xb << 60},
+		{0xe, 0x7 << 60},
+		{0xf, 0xf << 60},
+		{0x5686487, 0xe12616a000000000},
+		{0x0123456789abcdef, 0xf7b3d591e6a2c480},
+	} {
+		testReverse(t, test.x, test.r)
+		testReverse(t, test.r, test.x)
+	}
+}
+
+func testReverse(t *testing.T, x64, want64 uint64) {
+	x8 := uint8(x64)
+	got8 := Reverse8(x8)
+	want8 := uint8(want64 >> (64 - 8))
+	if got8 != want8 {
+		t.Fatalf("Reverse8(%#02x) == %#02x; want %#02x", x8, got8, want8)
+	}
+
+	x16 := uint16(x64)
+	got16 := Reverse16(x16)
+	want16 := uint16(want64 >> (64 - 16))
+	if got16 != want16 {
+		t.Fatalf("Reverse16(%#04x) == %#04x; want %#04x", x16, got16, want16)
+	}
+
+	x32 := uint32(x64)
+	got32 := Reverse32(x32)
+	want32 := uint32(want64 >> (64 - 32))
+	if got32 != want32 {
+		t.Fatalf("Reverse32(%#08x) == %#08x; want %#08x", x32, got32, want32)
+	}
+	if UintSize == 32 {
+		x := uint(x32)
+		got := Reverse(x)
+		want := uint(want32)
+		if got != want {
+			t.Fatalf("Reverse(%#08x) == %#08x; want %#08x", x, got, want)
+		}
+	}
+
+	got64 := Reverse64(x64)
+	if got64 != want64 {
+		t.Fatalf("Reverse64(%#016x) == %#016x; want %#016x", x64, got64, want64)
+	}
+	if UintSize == 64 {
+		x := uint(x64)
+		got := Reverse(x)
+		want := uint(want64)
+		if got != want {
+			t.Fatalf("Reverse(%#08x) == %#016x; want %#016x", x, got, want)
+		}
+	}
+}
+
+func BenchmarkReverse(b *testing.B) {
+	var s uint
+	for i := 0; i < b.N; i++ {
+		s += Reverse(uint(i))
+	}
+	Output = int(s)
+}
+
+func BenchmarkReverse8(b *testing.B) {
+	var s uint8
+	for i := 0; i < b.N; i++ {
+		s += Reverse8(uint8(i))
+	}
+	Output = int(s)
+}
+
+func BenchmarkReverse16(b *testing.B) {
+	var s uint16
+	for i := 0; i < b.N; i++ {
+		s += Reverse16(uint16(i))
+	}
+	Output = int(s)
+}
+
+func BenchmarkReverse32(b *testing.B) {
+	var s uint32
+	for i := 0; i < b.N; i++ {
+		s += Reverse32(uint32(i))
+	}
+	Output = int(s)
+}
+
+func BenchmarkReverse64(b *testing.B) {
+	var s uint64
+	for i := 0; i < b.N; i++ {
+		s += Reverse64(uint64(i))
+	}
+	Output = int(s)
+}
+
+func TestReverseBytes(t *testing.T) {
+	for _, test := range []struct {
+		x, r uint64
+	}{
+		{0, 0},
+		{0x01, 0x01 << 56},
+		{0x0123, 0x2301 << 48},
+		{0x012345, 0x452301 << 40},
+		{0x01234567, 0x67452301 << 32},
+		{0x0123456789, 0x8967452301 << 24},
+		{0x0123456789ab, 0xab8967452301 << 16},
+		{0x0123456789abcd, 0xcdab8967452301 << 8},
+		{0x0123456789abcdef, 0xefcdab8967452301 << 0},
+	} {
+		testReverseBytes(t, test.x, test.r)
+		testReverseBytes(t, test.r, test.x)
+	}
+}
+
+func testReverseBytes(t *testing.T, x64, want64 uint64) {
+	x16 := uint16(x64)
+	got16 := ReverseBytes16(x16)
+	want16 := uint16(want64 >> (64 - 16))
+	if got16 != want16 {
+		t.Fatalf("ReverseBytes16(%#04x) == %#04x; want %#04x", x16, got16, want16)
+	}
+
+	x32 := uint32(x64)
+	got32 := ReverseBytes32(x32)
+	want32 := uint32(want64 >> (64 - 32))
+	if got32 != want32 {
+		t.Fatalf("ReverseBytes32(%#08x) == %#08x; want %#08x", x32, got32, want32)
+	}
+	if UintSize == 32 {
+		x := uint(x32)
+		got := ReverseBytes(x)
+		want := uint(want32)
+		if got != want {
+			t.Fatalf("ReverseBytes(%#08x) == %#08x; want %#08x", x, got, want)
+		}
+	}
+
+	got64 := ReverseBytes64(x64)
+	if got64 != want64 {
+		t.Fatalf("ReverseBytes64(%#016x) == %#016x; want %#016x", x64, got64, want64)
+	}
+	if UintSize == 64 {
+		x := uint(x64)
+		got := ReverseBytes(x)
+		want := uint(want64)
+		if got != want {
+			t.Fatalf("ReverseBytes(%#016x) == %#016x; want %#016x", x, got, want)
+		}
+	}
+}
+
+func BenchmarkReverseBytes(b *testing.B) {
+	var s uint
+	for i := 0; i < b.N; i++ {
+		s += ReverseBytes(uint(i))
+	}
+	Output = int(s)
+}
+
+func BenchmarkReverseBytes16(b *testing.B) {
+	var s uint16
+	for i := 0; i < b.N; i++ {
+		s += ReverseBytes16(uint16(i))
+	}
+	Output = int(s)
+}
+
+func BenchmarkReverseBytes32(b *testing.B) {
+	var s uint32
+	for i := 0; i < b.N; i++ {
+		s += ReverseBytes32(uint32(i))
+	}
+	Output = int(s)
+}
+
+func BenchmarkReverseBytes64(b *testing.B) {
+	var s uint64
+	for i := 0; i < b.N; i++ {
+		s += ReverseBytes64(uint64(i))
+	}
+	Output = int(s)
+}
+
+func TestLen(t *testing.T) {
+	for i := 0; i < 256; i++ {
+		len := 8 - tab[i].nlz
+		for k := 0; k < 64-8; k++ {
+			x := uint64(i) << uint(k)
+			want := 0
+			if x != 0 {
+				want = len + k
+			}
+			if x <= 1<<8-1 {
+				got := Len8(uint8(x))
+				if got != want {
+					t.Fatalf("Len8(%#02x) == %d; want %d", x, got, want)
+				}
+			}
+
+			if x <= 1<<16-1 {
+				got := Len16(uint16(x))
+				if got != want {
+					t.Fatalf("Len16(%#04x) == %d; want %d", x, got, want)
+				}
+			}
+
+			if x <= 1<<32-1 {
+				got := Len32(uint32(x))
+				if got != want {
+					t.Fatalf("Len32(%#08x) == %d; want %d", x, got, want)
+				}
+				if UintSize == 32 {
+					got := Len(uint(x))
+					if got != want {
+						t.Fatalf("Len(%#08x) == %d; want %d", x, got, want)
+					}
+				}
+			}
+
+			if x <= 1<<64-1 {
+				got := Len64(uint64(x))
+				if got != want {
+					t.Fatalf("Len64(%#016x) == %d; want %d", x, got, want)
+				}
+				if UintSize == 64 {
+					got := Len(uint(x))
+					if got != want {
+						t.Fatalf("Len(%#016x) == %d; want %d", x, got, want)
+					}
+				}
+			}
+		}
+	}
+}
+
+// ----------------------------------------------------------------------------
+// Testing support
+
+type entry = struct {
+	nlz, ntz, pop int
+}
+
+// tab contains results for all uint8 values
+var tab [256]entry
+
+func init() {
+	tab[0] = entry{8, 8, 0}
+	for i := 1; i < len(tab); i++ {
+		// nlz
+		x := i // x != 0
+		n := 0
+		for x&0x80 == 0 {
+			n++
+			x <<= 1
+		}
+		tab[i].nlz = n
+
+		// ntz
+		x = i // x != 0
+		n = 0
+		for x&1 == 0 {
+			n++
+			x >>= 1
+		}
+		tab[i].ntz = n
+
+		// pop
+		x = i // x != 0
+		n = 0
+		for x != 0 {
+			n += int(x & 1)
+			x >>= 1
+		}
+		tab[i].pop = n
+	}
+}
diff --git a/libgo/go/math/bits/example_test.go b/libgo/go/math/bits/example_test.go
new file mode 100644
index 0000000..78750da
--- /dev/null
+++ b/libgo/go/math/bits/example_test.go
@@ -0,0 +1,80 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package bits_test
+
+import (
+	"fmt"
+	"math/bits"
+)
+
+func ExampleLeadingZeros16() {
+	fmt.Println(bits.LeadingZeros16(0))
+	fmt.Println(bits.LeadingZeros16(1))
+	fmt.Println(bits.LeadingZeros16(256))
+	fmt.Println(bits.LeadingZeros16(65535))
+	// Output:
+	// 16
+	// 15
+	// 7
+	// 0
+}
+
+func ExampleLeadingZeros32() {
+	fmt.Println(bits.LeadingZeros32(0))
+	fmt.Println(bits.LeadingZeros32(1))
+	// Output:
+	// 32
+	// 31
+}
+
+func ExampleLeadingZeros64() {
+	fmt.Println(bits.LeadingZeros64(0))
+	fmt.Println(bits.LeadingZeros64(1))
+	// Output:
+	// 64
+	// 63
+}
+
+func ExampleOnesCount() {
+	fmt.Printf("%b\n", 14)
+	fmt.Println(bits.OnesCount(14))
+	// Output:
+	// 1110
+	// 3
+}
+
+func ExampleOnesCount8() {
+	fmt.Printf("%b\n", 14)
+	fmt.Println(bits.OnesCount8(14))
+	// Output:
+	// 1110
+	// 3
+}
+
+func ExampleOnesCount16() {
+	fmt.Printf("%b\n", 14)
+	fmt.Println(bits.OnesCount16(14))
+	// Output:
+	// 1110
+	// 3
+}
+
+func ExampleOnesCount32() {
+	fmt.Printf("%b\n", 14)
+	fmt.Println(bits.OnesCount32(14))
+	// Output:
+	// 1110
+	// 3
+}
+
+func ExampleOnesCount64() {
+	fmt.Printf("%b\n", 14)
+	fmt.Println(bits.OnesCount64(14))
+	// Output:
+	// 1110
+	// 3
+}
diff --git a/libgo/go/math/bits/make_tables.go b/libgo/go/math/bits/make_tables.go
new file mode 100644
index 0000000..ff2fe2e
--- /dev/null
+++ b/libgo/go/math/bits/make_tables.go
@@ -0,0 +1,92 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// This program generates bits_tables.go.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"go/format"
+	"io"
+	"io/ioutil"
+	"log"
+)
+
+var header = []byte(`// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by go run make_tables.go. DO NOT EDIT.
+
+package bits
+
+`)
+
+func main() {
+	buf := bytes.NewBuffer(header)
+
+	gen(buf, "ntz8tab", ntz8)
+	gen(buf, "pop8tab", pop8)
+	gen(buf, "rev8tab", rev8)
+	gen(buf, "len8tab", len8)
+
+	out, err := format.Source(buf.Bytes())
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = ioutil.WriteFile("bits_tables.go", out, 0666)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func gen(w io.Writer, name string, f func(uint8) uint8) {
+	fmt.Fprintf(w, "var %s = [256]uint8{", name)
+	for i := 0; i < 256; i++ {
+		if i%16 == 0 {
+			fmt.Fprint(w, "\n\t")
+		} else {
+			fmt.Fprint(w, " ")
+		}
+		fmt.Fprintf(w, "%#02x,", f(uint8(i)))
+	}
+	fmt.Fprint(w, "\n}\n\n")
+}
+
+func ntz8(x uint8) (n uint8) {
+	for x&1 == 0 && n < 8 {
+		x >>= 1
+		n++
+	}
+	return
+}
+
+func pop8(x uint8) (n uint8) {
+	for x != 0 {
+		x &= x - 1
+		n++
+	}
+	return
+}
+
+func rev8(x uint8) (r uint8) {
+	for i := 8; i > 0; i-- {
+		r = r<<1 | x&1
+		x >>= 1
+	}
+	return
+}
+
+func len8(x uint8) (n uint8) {
+	for x != 0 {
+		x >>= 1
+		n++
+	}
+	return
+}
diff --git a/libgo/go/math/cbrt.go b/libgo/go/math/cbrt.go
index f009faf..374ab6d 100644
--- a/libgo/go/math/cbrt.go
+++ b/libgo/go/math/cbrt.go
@@ -23,6 +23,13 @@
 //	Cbrt(±Inf) = ±Inf
 //	Cbrt(NaN) = NaN
 func Cbrt(x float64) float64 {
+	return libc_cbrt(x)
+}
+
+//extern cbrt
+func libc_cbrt(float64) float64
+
+func cbrt(x float64) float64 {
 	const (
 		B1             = 715094163                   // (682-0.03306235651)*2**20
 		B2             = 696219795                   // (664-0.03306235651)*2**20
diff --git a/libgo/go/math/const.go b/libgo/go/math/const.go
index b440538..20b7065 100644
--- a/libgo/go/math/const.go
+++ b/libgo/go/math/const.go
@@ -3,6 +3,8 @@
 // license that can be found in the LICENSE file.
 
 // Package math provides basic constants and mathematical functions.
+//
+// This package does not guarantee bit-identical results across architectures.
 package math
 
 // Mathematical constants.
diff --git a/libgo/go/math/erf.go b/libgo/go/math/erf.go
index 8ddd5f9..e2a0422 100644
--- a/libgo/go/math/erf.go
+++ b/libgo/go/math/erf.go
@@ -186,6 +186,13 @@
 //	Erf(-Inf) = -1
 //	Erf(NaN) = NaN
 func Erf(x float64) float64 {
+	return libc_erf(x)
+}
+
+//extern erf
+func libc_erf(float64) float64
+
+func erf(x float64) float64 {
 	const (
 		VeryTiny = 2.848094538889218e-306 // 0x0080000000000000
 		Small    = 1.0 / (1 << 28)        // 2**-28
@@ -263,6 +270,13 @@
 //	Erfc(-Inf) = 2
 //	Erfc(NaN) = NaN
 func Erfc(x float64) float64 {
+	return libc_erfc(x)
+}
+
+//extern erfc
+func libc_erfc(float64) float64
+
+func erfc(x float64) float64 {
 	const Tiny = 1.0 / (1 << 56) // 2**-56
 	// special cases
 	switch {
diff --git a/libgo/go/math/example_test.go b/libgo/go/math/example_test.go
new file mode 100644
index 0000000..12e9876
--- /dev/null
+++ b/libgo/go/math/example_test.go
@@ -0,0 +1,20 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math_test
+
+import (
+	"fmt"
+	"math"
+)
+
+func ExampleSqrt() {
+	const (
+		a = 3
+		b = 4
+	)
+	c := math.Sqrt(a*a + b*b)
+	fmt.Printf("%.1f", c)
+	// Output: 5.0
+}
diff --git a/libgo/go/math/export_s390x_test.go b/libgo/go/math/export_s390x_test.go
index 2e7f584..3a52d6b 100644
--- a/libgo/go/math/export_s390x_test.go
+++ b/libgo/go/math/export_s390x_test.go
@@ -13,4 +13,21 @@
 var SinNoVec = sin
 var SinhNoVec = sinh
 var TanhNoVec = tanh
+var Log1pNovec = log1p
+var AtanhNovec = atanh
+var AcosNovec = acos
+var AcoshNovec = acosh
+var AsinNovec = asin
+var AsinhNovec = asinh
+var ErfNovec = erf
+var ErfcNovec = erfc
+var AtanNovec = atan
+var Atan2Novec = atan2
+var CbrtNovec = cbrt
+var LogNovec = log
+var TanNovec = tan
+var ExpNovec = exp
+var Expm1Novec = expm1
+var PowNovec = pow
+var HypotNovec = hypot
 var HasVX = hasVX
diff --git a/libgo/go/math/floor_asm.go b/libgo/go/math/floor_asm.go
index 9a2487a..761349a 100644
--- a/libgo/go/math/floor_asm.go
+++ b/libgo/go/math/floor_asm.go
@@ -7,7 +7,6 @@
 
 package math
 
-//defined in floor_amd64.s
-func hasSSE4() bool
+import "internal/cpu"
 
-var useSSE4 = hasSSE4()
+var useSSE41 = cpu.X86.HasSSE41
diff --git a/libgo/go/math/jn.go b/libgo/go/math/jn.go
index 3422782..4a8ddfa 100644
--- a/libgo/go/math/jn.go
+++ b/libgo/go/math/jn.go
@@ -226,10 +226,10 @@
 //
 // Special cases are:
 //	Yn(n, +Inf) = 0
-//	Yn(n > 0, 0) = -Inf
+//	Yn(n ≥ 0, 0) = -Inf
 //	Yn(n < 0, 0) = +Inf if n is odd, -Inf if n is even
-//	Y1(n, x < 0) = NaN
-//	Y1(n, NaN) = NaN
+//	Yn(n, x < 0) = NaN
+//	Yn(n, NaN) = NaN
 func Yn(n int, x float64) float64 {
 	const Two302 = 1 << 302 // 2**302 0x52D0000000000000
 	// special cases
diff --git a/libgo/go/math/pow.go b/libgo/go/math/pow.go
index 77af256..7ba426f4 100644
--- a/libgo/go/math/pow.go
+++ b/libgo/go/math/pow.go
@@ -36,6 +36,13 @@
 //	Pow(-Inf, y) = Pow(-0, -y)
 //	Pow(x, y) = NaN for finite x < 0 and finite non-integer y
 func Pow(x, y float64) float64 {
+	return libc_pow(x, y)
+}
+
+//extern pow
+func libc_pow(float64, float64) float64
+
+func pow(x, y float64) float64 {
 	switch {
 	case y == 0 || x == 1:
 		return 1
diff --git a/libgo/go/math/pow10.go b/libgo/go/math/pow10.go
index f5ad28b..1234e20 100644
--- a/libgo/go/math/pow10.go
+++ b/libgo/go/math/pow10.go
@@ -4,37 +4,43 @@
 
 package math
 
-// This table might overflow 127-bit exponent representations.
-// In that case, truncate it after 1.0e38.
-var pow10tab [70]float64
+// pow10tab stores the pre-computed values 10**i for i < 32.
+var pow10tab = [...]float64{
+	1e00, 1e01, 1e02, 1e03, 1e04, 1e05, 1e06, 1e07, 1e08, 1e09,
+	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
+	1e20, 1e21, 1e22, 1e23, 1e24, 1e25, 1e26, 1e27, 1e28, 1e29,
+	1e30, 1e31,
+}
 
-// Pow10 returns 10**e, the base-10 exponential of e.
+// pow10postab32 stores the pre-computed value for 10**(i*32) at index i.
+var pow10postab32 = [...]float64{
+	1e00, 1e32, 1e64, 1e96, 1e128, 1e160, 1e192, 1e224, 1e256, 1e288,
+}
+
+// pow10negtab32 stores the pre-computed value for 10**(-i*32) at index i.
+var pow10negtab32 = [...]float64{
+	1e-00, 1e-32, 1e-64, 1e-96, 1e-128, 1e-160, 1e-192, 1e-224, 1e-256, 1e-288, 1e-320,
+}
+
+// Pow10 returns 10**n, the base-10 exponential of n.
 //
 // Special cases are:
-//	Pow10(e) = +Inf for e > 309
-//	Pow10(e) = 0 for e < -324
-func Pow10(e int) float64 {
-	if e <= -325 {
-		return 0
-	} else if e > 309 {
+//	Pow10(n) =    0 for n < -323
+//	Pow10(n) = +Inf for n > 308
+func Pow10(n int) float64 {
+	if 0 <= n && n <= 308 {
+		return pow10postab32[uint(n)/32] * pow10tab[uint(n)%32]
+	}
+
+	if -323 <= n && n <= 0 {
+		return pow10negtab32[uint(-n)/32] / pow10tab[uint(-n)%32]
+	}
+
+	// n < -323 || 308 < n
+	if n > 0 {
 		return Inf(1)
 	}
 
-	if e < 0 {
-		return 1 / Pow10(-e)
-	}
-	if e < len(pow10tab) {
-		return pow10tab[e]
-	}
-	m := e / 2
-	return Pow10(m) * Pow10(e-m)
-}
-
-func init() {
-	pow10tab[0] = 1.0e0
-	pow10tab[1] = 1.0e1
-	for i := 2; i < len(pow10tab); i++ {
-		m := i / 2
-		pow10tab[i] = pow10tab[m] * pow10tab[i-m]
-	}
+	// n < -323
+	return 0
 }
diff --git a/libgo/go/math/rand/rand.go b/libgo/go/math/rand/rand.go
index 9fe1cbd..fe99c94 100644
--- a/libgo/go/math/rand/rand.go
+++ b/libgo/go/math/rand/rand.go
@@ -8,7 +8,8 @@
 // Float64 and Int, use a default shared Source that produces a deterministic
 // sequence of values each time a program is run. Use the Seed function to
 // initialize the default Source if different behavior is required for each run.
-// The default Source is safe for concurrent use by multiple goroutines.
+// The default Source is safe for concurrent use by multiple goroutines, but
+// Sources created by NewSource are not.
 //
 // For random numbers suitable for security-sensitive work, see the crypto/rand
 // package.
diff --git a/libgo/go/math/sincos.go b/libgo/go/math/sincos.go
index 89db81e..65f3790 100644
--- a/libgo/go/math/sincos.go
+++ b/libgo/go/math/sincos.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// -build !386
+
 package math
 
 // Coefficients _sin[] and _cos[] are found in pkg/math/sin.go.
@@ -13,10 +15,6 @@
 //	Sincos(±Inf) = NaN, NaN
 //	Sincos(NaN) = NaN, NaN
 func Sincos(x float64) (sin, cos float64) {
-	return sincos(x)
-}
-
-func sincos(x float64) (sin, cos float64) {
 	const (
 		PI4A = 7.85398125648498535156E-1                             // 0x3fe921fb40000000, Pi/4 split into three parts
 		PI4B = 3.77489470793079817668E-8                             // 0x3e64442d00000000,
diff --git a/libgo/go/math/sincos_386.go b/libgo/go/math/sincos_386.go
new file mode 100644
index 0000000..d5c2457
--- /dev/null
+++ b/libgo/go/math/sincos_386.go
@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package math
+
+// Sincos returns Sin(x), Cos(x).
+//
+// Special cases are:
+//	Sincos(±0) = ±0, 1
+//	Sincos(±Inf) = NaN, NaN
+//	Sincos(NaN) = NaN, NaN
+func Sincos(x float64) (sin, cos float64)
diff --git a/libgo/go/mime/encodedword.go b/libgo/go/mime/encodedword.go
index c3ca4ba..99eb432 100644
--- a/libgo/go/mime/encodedword.go
+++ b/libgo/go/mime/encodedword.go
@@ -188,27 +188,35 @@
 	// charset into UTF-8.
 	// Charsets are always lower-case. utf-8, iso-8859-1 and us-ascii charsets
 	// are handled by default.
-	// One of the the CharsetReader's result values must be non-nil.
+	// One of the CharsetReader's result values must be non-nil.
 	CharsetReader func(charset string, input io.Reader) (io.Reader, error)
 }
 
 // Decode decodes an RFC 2047 encoded-word.
 func (d *WordDecoder) Decode(word string) (string, error) {
-	if !strings.HasPrefix(word, "=?") || !strings.HasSuffix(word, "?=") || strings.Count(word, "?") != 4 {
+	// See https://tools.ietf.org/html/rfc2047#section-2 for details.
+	// Our decoder is permissive, we accept empty encoded-text.
+	if len(word) < 8 || !strings.HasPrefix(word, "=?") || !strings.HasSuffix(word, "?=") || strings.Count(word, "?") != 4 {
 		return "", errInvalidWord
 	}
 	word = word[2 : len(word)-2]
 
 	// split delimits the first 2 fields
 	split := strings.IndexByte(word, '?')
+
+	// split word "UTF-8?q?ascii" into "UTF-8", 'q', and "ascii"
+	charset := word[:split]
+	if len(charset) == 0 {
+		return "", errInvalidWord
+	}
+	if len(word) < split+3 {
+		return "", errInvalidWord
+	}
+	encoding := word[split+1]
 	// the field after split must only be one byte
 	if word[split+2] != '?' {
 		return "", errInvalidWord
 	}
-
-	// split word "UTF-8?q?ascii" into "UTF-8", 'q', and "ascii"
-	charset := word[:split]
-	encoding := word[split+1]
 	text := word[split+3:]
 
 	content, err := decode(encoding, text)
diff --git a/libgo/go/mime/encodedword_test.go b/libgo/go/mime/encodedword_test.go
index b7ca4d0..6c54e50 100644
--- a/libgo/go/mime/encodedword_test.go
+++ b/libgo/go/mime/encodedword_test.go
@@ -88,6 +88,9 @@
 		{"=?UTF-8?Q?A=B?=", "", true},
 		{"=?UTF-8?Q?=A?=", "", true},
 		{"=?UTF-8?A?A?=", "", true},
+		{"=????=", "", true},
+		{"=?UTF-8???=", "", true},
+		{"=?UTF-8?Q??=", "", false},
 	}
 
 	for _, test := range tests {
diff --git a/libgo/go/mime/mediatype.go b/libgo/go/mime/mediatype.go
index 75cc903..5557672 100644
--- a/libgo/go/mime/mediatype.go
+++ b/libgo/go/mime/mediatype.go
@@ -94,11 +94,19 @@
 	return nil
 }
 
+// ErrInvalidMediaParameter is returned by ParseMediaType if
+// the media type value was found but there was an error parsing
+// the optional parameters
+var ErrInvalidMediaParameter = errors.New("mime: invalid media parameter")
+
 // ParseMediaType parses a media type value and any optional
 // parameters, per RFC 1521.  Media types are the values in
 // Content-Type and Content-Disposition headers (RFC 2183).
 // On success, ParseMediaType returns the media type converted
 // to lowercase and trimmed of white space and a non-nil map.
+// If there is an error parsing the optional parameter,
+// the media type will be returned along with the error
+// ErrInvalidMediaParameter.
 // The returned map, params, maps from the lowercase
 // attribute to the attribute value with its case preserved.
 func ParseMediaType(v string) (mediatype string, params map[string]string, err error) {
@@ -134,7 +142,7 @@
 				return
 			}
 			// Parse error.
-			return "", nil, errors.New("mime: invalid media parameter")
+			return mediatype, nil, ErrInvalidMediaParameter
 		}
 
 		pmap := params
diff --git a/libgo/go/mime/mediatype_test.go b/libgo/go/mime/mediatype_test.go
index c5fc906..3ba8ee1 100644
--- a/libgo/go/mime/mediatype_test.go
+++ b/libgo/go/mime/mediatype_test.go
@@ -253,13 +253,18 @@
 
 type badMediaTypeTest struct {
 	in  string
+	mt  string
 	err string
 }
 
 var badMediaTypeTests = []badMediaTypeTest{
-	{"bogus ;=========", "mime: invalid media parameter"},
-	{"bogus/<script>alert</script>", "mime: expected token after slash"},
-	{"bogus/bogus<script>alert</script>", "mime: unexpected content after media subtype"},
+	{"bogus ;=========", "bogus", "mime: invalid media parameter"},
+	// The following example is from real email delivered by gmail (error: missing semicolon)
+	// and it is there to check behavior described in #19498
+	{"application/pdf; x-mac-type=\"3F3F3F3F\"; x-mac-creator=\"3F3F3F3F\" name=\"a.pdf\";",
+		"application/pdf", "mime: invalid media parameter"},
+	{"bogus/<script>alert</script>", "", "mime: expected token after slash"},
+	{"bogus/bogus<script>alert</script>", "", "mime: unexpected content after media subtype"},
 }
 
 func TestParseMediaTypeBogus(t *testing.T) {
@@ -275,8 +280,11 @@
 		if params != nil {
 			t.Errorf("ParseMediaType(%q): got non-nil params on error", tt.in)
 		}
-		if mt != "" {
-			t.Errorf("ParseMediaType(%q): got non-empty media type string on error", tt.in)
+		if err != ErrInvalidMediaParameter && mt != "" {
+			t.Errorf("ParseMediaType(%q): got unexpected non-empty media type string", tt.in)
+		}
+		if err == ErrInvalidMediaParameter && mt != tt.mt {
+			t.Errorf("ParseMediaType(%q): in case of invalid parameters: expected type %q, got %q", tt.in, tt.mt, mt)
 		}
 	}
 }
diff --git a/libgo/go/mime/multipart/formdata.go b/libgo/go/mime/multipart/formdata.go
index c9e3188..832d0ad 100644
--- a/libgo/go/mime/multipart/formdata.go
+++ b/libgo/go/mime/multipart/formdata.go
@@ -13,13 +13,20 @@
 	"os"
 )
 
+// ErrMessageTooLarge is returned by ReadForm if the message form
+// data is too large to be processed.
+var ErrMessageTooLarge = errors.New("multipart: message too large")
+
 // TODO(adg,bradfitz): find a way to unify the DoS-prevention strategy here
 // with that of the http package's ParseForm.
 
 // ReadForm parses an entire multipart message whose parts have
 // a Content-Disposition of "form-data".
-// It stores up to maxMemory bytes of the file parts in memory
-// and the remainder on disk in temporary files.
+// It stores up to maxMemory bytes + 10MB (reserved for non-file parts)
+// in memory. File parts which can't be stored in memory will be stored on
+// disk in temporary files.
+// It returns ErrMessageTooLarge if all non-file parts can't be stored in
+// memory.
 func (r *Reader) ReadForm(maxMemory int64) (*Form, error) {
 	return r.readForm(maxMemory)
 }
@@ -32,7 +39,8 @@
 		}
 	}()
 
-	maxValueBytes := int64(10 << 20) // 10 MB is a lot of text.
+	// Reserve an additional 10 MB for non-file parts.
+	maxValueBytes := maxMemory + int64(10<<20)
 	for {
 		p, err := r.NextPart()
 		if err == io.EOF {
@@ -52,13 +60,13 @@
 
 		if filename == "" {
 			// value, store as string in memory
-			n, err := io.CopyN(&b, p, maxValueBytes)
+			n, err := io.CopyN(&b, p, maxValueBytes+1)
 			if err != nil && err != io.EOF {
 				return nil, err
 			}
 			maxValueBytes -= n
-			if maxValueBytes == 0 {
-				return nil, errors.New("multipart: message too large")
+			if maxValueBytes < 0 {
+				return nil, ErrMessageTooLarge
 			}
 			form.Value[name] = append(form.Value[name], b.String())
 			continue
@@ -79,7 +87,7 @@
 			if err != nil {
 				return nil, err
 			}
-			_, err = io.Copy(file, io.MultiReader(&b, p))
+			size, err := io.Copy(file, io.MultiReader(&b, p))
 			if cerr := file.Close(); err == nil {
 				err = cerr
 			}
@@ -88,9 +96,12 @@
 				return nil, err
 			}
 			fh.tmpfile = file.Name()
+			fh.Size = size
 		} else {
 			fh.content = b.Bytes()
+			fh.Size = int64(len(fh.content))
 			maxMemory -= n
+			maxValueBytes -= n
 		}
 		form.File[name] = append(form.File[name], fh)
 	}
@@ -128,6 +139,7 @@
 type FileHeader struct {
 	Filename string
 	Header   textproto.MIMEHeader
+	Size     int64
 
 	content []byte
 	tmpfile string
diff --git a/libgo/go/mime/multipart/formdata_test.go b/libgo/go/mime/multipart/formdata_test.go
index 1deca0b..979ae5c 100644
--- a/libgo/go/mime/multipart/formdata_test.go
+++ b/libgo/go/mime/multipart/formdata_test.go
@@ -8,14 +8,12 @@
 	"bytes"
 	"io"
 	"os"
-	"regexp"
 	"strings"
 	"testing"
 )
 
 func TestReadForm(t *testing.T) {
-	testBody := regexp.MustCompile("\n").ReplaceAllString(message, "\r\n")
-	b := strings.NewReader(testBody)
+	b := strings.NewReader(strings.Replace(message, "\n", "\r\n", -1))
 	r := NewReader(b, boundary)
 	f, err := r.ReadForm(25)
 	if err != nil {
@@ -44,6 +42,9 @@
 	if fh.Filename != efn {
 		t.Errorf("filename = %q, want %q", fh.Filename, efn)
 	}
+	if fh.Size != int64(len(econtent)) {
+		t.Errorf("size = %d, want %d", fh.Size, len(econtent))
+	}
 	f, err := fh.Open()
 	if err != nil {
 		t.Fatal("opening file:", err)
@@ -124,3 +125,44 @@
 	r.sawErr = err
 	return
 }
+
+// TestReadForm_NonFileMaxMemory asserts that the ReadForm maxMemory limit is applied
+// while processing non-file form data as well as file form data.
+func TestReadForm_NonFileMaxMemory(t *testing.T) {
+	largeTextValue := strings.Repeat("1", (10<<20)+25)
+	message := `--MyBoundary
+Content-Disposition: form-data; name="largetext"
+
+` + largeTextValue + `
+--MyBoundary--
+`
+
+	testBody := strings.Replace(message, "\n", "\r\n", -1)
+	testCases := []struct {
+		name      string
+		maxMemory int64
+		err       error
+	}{
+		{"smaller", 50, nil},
+		{"exact-fit", 25, nil},
+		{"too-large", 0, ErrMessageTooLarge},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			b := strings.NewReader(testBody)
+			r := NewReader(b, boundary)
+			f, err := r.ReadForm(tc.maxMemory)
+			if err == nil {
+				defer f.RemoveAll()
+			}
+			if tc.err != err {
+				t.Fatalf("ReadForm error - got: %v; expected: %v", tc.err, err)
+			}
+			if err == nil {
+				if g := f.Value["largetext"][0]; g != largeTextValue {
+					t.Errorf("largetext mismatch: got size: %v, expected size: %v", len(g), len(largeTextValue))
+				}
+			}
+		})
+	}
+}
diff --git a/libgo/go/mime/multipart/writer.go b/libgo/go/mime/multipart/writer.go
index f82756d..3dd0c8f 100644
--- a/libgo/go/mime/multipart/writer.go
+++ b/libgo/go/mime/multipart/writer.go
@@ -41,22 +41,27 @@
 //
 // SetBoundary must be called before any parts are created, may only
 // contain certain ASCII characters, and must be non-empty and
-// at most 69 bytes long.
+// at most 70 bytes long.
 func (w *Writer) SetBoundary(boundary string) error {
 	if w.lastpart != nil {
 		return errors.New("mime: SetBoundary called after write")
 	}
 	// rfc2046#section-5.1.1
-	if len(boundary) < 1 || len(boundary) > 69 {
+	if len(boundary) < 1 || len(boundary) > 70 {
 		return errors.New("mime: invalid boundary length")
 	}
-	for _, b := range boundary {
+	end := len(boundary) - 1
+	for i, b := range boundary {
 		if 'A' <= b && b <= 'Z' || 'a' <= b && b <= 'z' || '0' <= b && b <= '9' {
 			continue
 		}
 		switch b {
 		case '\'', '(', ')', '+', '_', ',', '-', '.', '/', ':', '=', '?':
 			continue
+		case ' ':
+			if i != end {
+				continue
+			}
 		}
 		return errors.New("mime: invalid boundary character")
 	}
diff --git a/libgo/go/mime/multipart/writer_test.go b/libgo/go/mime/multipart/writer_test.go
index 9670c66..8b1bcd6 100644
--- a/libgo/go/mime/multipart/writer_test.go
+++ b/libgo/go/mime/multipart/writer_test.go
@@ -80,8 +80,6 @@
 }
 
 func TestWriterSetBoundary(t *testing.T) {
-	var b bytes.Buffer
-	w := NewWriter(&b)
 	tests := []struct {
 		b  string
 		ok bool
@@ -90,12 +88,16 @@
 		{"", false},
 		{"ungültig", false},
 		{"!", false},
-		{strings.Repeat("x", 69), true},
-		{strings.Repeat("x", 70), false},
+		{strings.Repeat("x", 70), true},
+		{strings.Repeat("x", 71), false},
 		{"bad!ascii!", false},
 		{"my-separator", true},
+		{"with space", true},
+		{"badspace ", false},
 	}
 	for i, tt := range tests {
+		var b bytes.Buffer
+		w := NewWriter(&b)
 		err := w.SetBoundary(tt.b)
 		got := err == nil
 		if got != tt.ok {
@@ -105,12 +107,13 @@
 			if got != tt.b {
 				t.Errorf("boundary = %q; want %q", got, tt.b)
 			}
+			w.Close()
+			wantSub := "\r\n--" + tt.b + "--\r\n"
+			if got := b.String(); !strings.Contains(got, wantSub) {
+				t.Errorf("expected %q in output. got: %q", wantSub, got)
+			}
 		}
 	}
-	w.Close()
-	if got := b.String(); !strings.Contains(got, "\r\n--my-separator--\r\n") {
-		t.Errorf("expected my-separator in output. got: %q", got)
-	}
 }
 
 func TestWriterBoundaryGoroutines(t *testing.T) {
diff --git a/libgo/go/mime/type.go b/libgo/go/mime/type.go
index d369259..78fc6b6 100644
--- a/libgo/go/mime/type.go
+++ b/libgo/go/mime/type.go
@@ -12,24 +12,48 @@
 )
 
 var (
-	mimeLock       sync.RWMutex      // guards following 3 maps
-	mimeTypes      map[string]string // ".Z" => "application/x-compress"
-	mimeTypesLower map[string]string // ".z" => "application/x-compress"
+	mimeTypes      sync.Map // map[string]string; ".Z" => "application/x-compress"
+	mimeTypesLower sync.Map // map[string]string; ".z" => "application/x-compress"
 
 	// extensions maps from MIME type to list of lowercase file
 	// extensions: "image/jpeg" => [".jpg", ".jpeg"]
-	extensions map[string][]string
+	extensionsMu sync.Mutex // Guards stores (but not loads) on extensions.
+	extensions   sync.Map   // map[string][]string; slice values are append-only.
 )
 
+func clearSyncMap(m *sync.Map) {
+	m.Range(func(k, _ interface{}) bool {
+		m.Delete(k)
+		return true
+	})
+}
+
 // setMimeTypes is used by initMime's non-test path, and by tests.
-// The two maps must not be the same, or nil.
 func setMimeTypes(lowerExt, mixExt map[string]string) {
-	if lowerExt == nil || mixExt == nil {
-		panic("nil map")
+	clearSyncMap(&mimeTypes)
+	clearSyncMap(&mimeTypesLower)
+	clearSyncMap(&extensions)
+
+	for k, v := range lowerExt {
+		mimeTypesLower.Store(k, v)
 	}
-	mimeTypesLower = lowerExt
-	mimeTypes = mixExt
-	extensions = invert(lowerExt)
+	for k, v := range mixExt {
+		mimeTypes.Store(k, v)
+	}
+
+	extensionsMu.Lock()
+	defer extensionsMu.Unlock()
+	for k, v := range lowerExt {
+		justType, _, err := ParseMediaType(v)
+		if err != nil {
+			panic(err)
+		}
+		var exts []string
+		if ei, ok := extensions.Load(k); ok {
+			exts = ei.([]string)
+		}
+		extensions.Store(justType, append(exts, k))
+	}
 }
 
 var builtinTypesLower = map[string]string{
@@ -45,29 +69,6 @@
 	".xml":  "text/xml; charset=utf-8",
 }
 
-func clone(m map[string]string) map[string]string {
-	m2 := make(map[string]string, len(m))
-	for k, v := range m {
-		m2[k] = v
-		if strings.ToLower(k) != k {
-			panic("keys in builtinTypesLower must be lowercase")
-		}
-	}
-	return m2
-}
-
-func invert(m map[string]string) map[string][]string {
-	m2 := make(map[string][]string, len(m))
-	for k, v := range m {
-		justType, _, err := ParseMediaType(v)
-		if err != nil {
-			panic(err)
-		}
-		m2[justType] = append(m2[justType], k)
-	}
-	return m2
-}
-
 var once sync.Once // guards initMime
 
 var testInitMime, osInitMime func()
@@ -76,7 +77,7 @@
 	if fn := testInitMime; fn != nil {
 		fn()
 	} else {
-		setMimeTypes(builtinTypesLower, clone(builtinTypesLower))
+		setMimeTypes(builtinTypesLower, builtinTypesLower)
 		osInitMime()
 	}
 }
@@ -100,12 +101,10 @@
 // Text types have the charset parameter set to "utf-8" by default.
 func TypeByExtension(ext string) string {
 	once.Do(initMime)
-	mimeLock.RLock()
-	defer mimeLock.RUnlock()
 
 	// Case-sensitive lookup.
-	if v := mimeTypes[ext]; v != "" {
-		return v
+	if v, ok := mimeTypes.Load(ext); ok {
+		return v.(string)
 	}
 
 	// Case-insensitive lookup.
@@ -118,7 +117,9 @@
 		c := ext[i]
 		if c >= utf8RuneSelf {
 			// Slow path.
-			return mimeTypesLower[strings.ToLower(ext)]
+			si, _ := mimeTypesLower.Load(strings.ToLower(ext))
+			s, _ := si.(string)
+			return s
 		}
 		if 'A' <= c && c <= 'Z' {
 			lower = append(lower, c+('a'-'A'))
@@ -126,9 +127,9 @@
 			lower = append(lower, c)
 		}
 	}
-	// The conversion from []byte to string doesn't allocate in
-	// a map lookup.
-	return mimeTypesLower[string(lower)]
+	si, _ := mimeTypesLower.Load(string(lower))
+	s, _ := si.(string)
+	return s
 }
 
 // ExtensionsByType returns the extensions known to be associated with the MIME
@@ -142,13 +143,11 @@
 	}
 
 	once.Do(initMime)
-	mimeLock.RLock()
-	defer mimeLock.RUnlock()
-	s, ok := extensions[justType]
+	s, ok := extensions.Load(justType)
 	if !ok {
 		return nil, nil
 	}
-	return append([]string{}, s...), nil
+	return append([]string{}, s.([]string)...), nil
 }
 
 // AddExtensionType sets the MIME type associated with
@@ -173,15 +172,20 @@
 	}
 	extLower := strings.ToLower(extension)
 
-	mimeLock.Lock()
-	defer mimeLock.Unlock()
-	mimeTypes[extension] = mimeType
-	mimeTypesLower[extLower] = mimeType
-	for _, v := range extensions[justType] {
+	mimeTypes.Store(extension, mimeType)
+	mimeTypesLower.Store(extLower, mimeType)
+
+	extensionsMu.Lock()
+	defer extensionsMu.Unlock()
+	var exts []string
+	if ei, ok := extensions.Load(justType); ok {
+		exts = ei.([]string)
+	}
+	for _, v := range exts {
 		if v == extLower {
 			return nil
 		}
 	}
-	extensions[justType] = append(extensions[justType], extLower)
+	extensions.Store(justType, append(exts, extLower))
 	return nil
 }
diff --git a/libgo/go/mime/type_test.go b/libgo/go/mime/type_test.go
index 48735ef..de5c700 100644
--- a/libgo/go/mime/type_test.go
+++ b/libgo/go/mime/type_test.go
@@ -149,3 +149,43 @@
 		t.Errorf("allocs = %v; want 0", n)
 	}
 }
+
+func BenchmarkTypeByExtension(b *testing.B) {
+	initMime()
+	b.ResetTimer()
+
+	for _, ext := range []string{
+		".html",
+		".HTML",
+		".unused",
+	} {
+		b.Run(ext, func(b *testing.B) {
+			b.RunParallel(func(pb *testing.PB) {
+				for pb.Next() {
+					TypeByExtension(ext)
+				}
+			})
+		})
+	}
+}
+
+func BenchmarkExtensionsByType(b *testing.B) {
+	initMime()
+	b.ResetTimer()
+
+	for _, typ := range []string{
+		"text/html",
+		"text/html; charset=utf-8",
+		"application/octet-stream",
+	} {
+		b.Run(typ, func(b *testing.B) {
+			b.RunParallel(func(pb *testing.PB) {
+				for pb.Next() {
+					if _, err := ExtensionsByType(typ); err != nil {
+						b.Fatal(err)
+					}
+				}
+			})
+		})
+	}
+}
diff --git a/libgo/go/net/cgo_unix.go b/libgo/go/net/cgo_unix.go
index 09cfb2a..0de3ff8 100644
--- a/libgo/go/net/cgo_unix.go
+++ b/libgo/go/net/cgo_unix.go
@@ -220,7 +220,7 @@
 			addrs = append(addrs, addr)
 		case syscall.AF_INET6:
 			sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.Ai_addr))
-			addr := IPAddr{IP: copyIP(sa.Addr[:]), Zone: zoneToString(int(sa.Scope_id))}
+			addr := IPAddr{IP: copyIP(sa.Addr[:]), Zone: zoneCache.name(int(sa.Scope_id))}
 			addrs = append(addrs, addr)
 		}
 	}
@@ -345,7 +345,7 @@
 		return cgoSockaddrInet4(ip4), syscall.Socklen_t(syscall.SizeofSockaddrInet4)
 	}
 	if ip6 := ip.To16(); ip6 != nil {
-		return cgoSockaddrInet6(ip6, zoneToInt(zone)), syscall.Socklen_t(syscall.SizeofSockaddrInet6)
+		return cgoSockaddrInet6(ip6, zoneCache.index(zone)), syscall.Socklen_t(syscall.SizeofSockaddrInet6)
 	}
 	return nil, 0
 }
diff --git a/libgo/go/net/dial.go b/libgo/go/net/dial.go
index 50bba5a..f8b4aa2 100644
--- a/libgo/go/net/dial.go
+++ b/libgo/go/net/dial.go
@@ -7,6 +7,7 @@
 import (
 	"context"
 	"internal/nettrace"
+	"internal/poll"
 	"time"
 )
 
@@ -22,8 +23,8 @@
 	//
 	// The default is no timeout.
 	//
-	// When dialing a name with multiple IP addresses, the timeout
-	// may be divided between them.
+	// When using TCP and dialing a host name with multiple IP
+	// addresses, the timeout may be divided between them.
 	//
 	// With or without a timeout, the operating system may impose
 	// its own earlier timeout. For instance, TCP timeouts are
@@ -42,10 +43,11 @@
 	// If nil, a local address is automatically chosen.
 	LocalAddr Addr
 
-	// DualStack enables RFC 6555-compliant "Happy Eyeballs" dialing
-	// when the network is "tcp" and the destination is a host name
-	// with both IPv4 and IPv6 addresses. This allows a client to
-	// tolerate networks where one address family is silently broken.
+	// DualStack enables RFC 6555-compliant "Happy Eyeballs"
+	// dialing when the network is "tcp" and the host in the
+	// address parameter resolves to both IPv4 and IPv6 addresses.
+	// This allows a client to tolerate networks where one address
+	// family is silently broken.
 	DualStack bool
 
 	// FallbackDelay specifies the length of time to wait before
@@ -110,7 +112,7 @@
 	}
 	timeRemaining := deadline.Sub(now)
 	if timeRemaining <= 0 {
-		return time.Time{}, errTimeout
+		return time.Time{}, poll.ErrTimeout
 	}
 	// Tentatively allocate equal time to each remaining address.
 	timeout := timeRemaining / time.Duration(addrsRemaining)
@@ -134,23 +136,26 @@
 	}
 }
 
-func parseNetwork(ctx context.Context, net string) (afnet string, proto int, err error) {
-	i := last(net, ':')
+func parseNetwork(ctx context.Context, network string, needsProto bool) (afnet string, proto int, err error) {
+	i := last(network, ':')
 	if i < 0 { // no colon
-		switch net {
+		switch network {
 		case "tcp", "tcp4", "tcp6":
 		case "udp", "udp4", "udp6":
 		case "ip", "ip4", "ip6":
+			if needsProto {
+				return "", 0, UnknownNetworkError(network)
+			}
 		case "unix", "unixgram", "unixpacket":
 		default:
-			return "", 0, UnknownNetworkError(net)
+			return "", 0, UnknownNetworkError(network)
 		}
-		return net, 0, nil
+		return network, 0, nil
 	}
-	afnet = net[:i]
+	afnet = network[:i]
 	switch afnet {
 	case "ip", "ip4", "ip6":
-		protostr := net[i+1:]
+		protostr := network[i+1:]
 		proto, i, ok := dtoi(protostr)
 		if !ok || i != len(protostr) {
 			proto, err = lookupProtocol(ctx, protostr)
@@ -160,14 +165,14 @@
 		}
 		return afnet, proto, nil
 	}
-	return "", 0, UnknownNetworkError(net)
+	return "", 0, UnknownNetworkError(network)
 }
 
 // resolveAddrList resolves addr using hint and returns a list of
 // addresses. The result contains at least one address when error is
 // nil.
 func (r *Resolver) resolveAddrList(ctx context.Context, op, network, addr string, hint Addr) (addrList, error) {
-	afnet, _, err := parseNetwork(ctx, network)
+	afnet, _, err := parseNetwork(ctx, network, true)
 	if err != nil {
 		return nil, err
 	}
@@ -242,39 +247,60 @@
 // (IPv4-only), "ip6" (IPv6-only), "unix", "unixgram" and
 // "unixpacket".
 //
-// For TCP and UDP networks, addresses have the form host:port.
-// If host is a literal IPv6 address it must be enclosed
-// in square brackets as in "[::1]:80" or "[ipv6-host%zone]:80".
-// The functions JoinHostPort and SplitHostPort manipulate addresses
-// in this form.
-// If the host is empty, as in ":80", the local system is assumed.
+// For TCP and UDP networks, the address has the form "host:port".
+// The host must be a literal IP address, or a host name that can be
+// resolved to IP addresses.
+// The port must be a literal port number or a service name.
+// If the host is a literal IPv6 address it must be enclosed in square
+// brackets, as in "[2001:db8::1]:80" or "[fe80::1%zone]:80".
+// The zone specifies the scope of the literal IPv6 address as defined
+// in RFC 4007.
+// The functions JoinHostPort and SplitHostPort manipulate a pair of
+// host and port in this form.
+// When using TCP, and the host resolves to multiple IP addresses,
+// Dial will try each IP address in order until one succeeds.
 //
 // Examples:
-//	Dial("tcp", "192.0.2.1:80")
 //	Dial("tcp", "golang.org:http")
-//	Dial("tcp", "[2001:db8::1]:http")
-//	Dial("tcp", "[fe80::1%lo0]:80")
+//	Dial("tcp", "192.0.2.1:http")
+//	Dial("tcp", "198.51.100.1:80")
+//	Dial("udp", "[2001:db8::1]:domain")
+//	Dial("udp", "[fe80::1%lo0]:53")
 //	Dial("tcp", ":80")
 //
 // For IP networks, the network must be "ip", "ip4" or "ip6" followed
-// by a colon and a protocol number or name and the addr must be a
-// literal IP address.
+// by a colon and a literal protocol number or a protocol name, and
+// the address has the form "host". The host must be a literal IP
+// address or a literal IPv6 address with zone.
+// It depends on each operating system how the operating system
+// behaves with a non-well known protocol number such as "0" or "255".
 //
 // Examples:
 //	Dial("ip4:1", "192.0.2.1")
 //	Dial("ip6:ipv6-icmp", "2001:db8::1")
+//	Dial("ip6:58", "fe80::1%lo0")
+//
+// For TCP, UDP and IP networks, if the host is empty or a literal
+// unspecified IP address, as in ":80", "0.0.0.0:80" or "[::]:80" for
+// TCP and UDP, "", "0.0.0.0" or "::" for IP, the local system is
+// assumed.
 //
 // For Unix networks, the address must be a file system path.
-//
-// If the host is resolved to multiple addresses,
-// Dial will try each address in order until one succeeds.
 func Dial(network, address string) (Conn, error) {
 	var d Dialer
 	return d.Dial(network, address)
 }
 
 // DialTimeout acts like Dial but takes a timeout.
+//
 // The timeout includes name resolution, if required.
+// When using TCP, and the host in the address parameter resolves to
+// multiple IP addresses, the timeout is spread over each consecutive
+// dial, such that each is given an appropriate fraction of the time
+// to connect.
+//
+// See func Dial for a description of the network and address
+// parameters.
 func DialTimeout(network, address string, timeout time.Duration) (Conn, error) {
 	d := Dialer{Timeout: timeout}
 	return d.Dial(network, address)
@@ -537,29 +563,37 @@
 	return c, nil
 }
 
-// Listen announces on the local network address laddr.
-// The network net must be a stream-oriented network: "tcp", "tcp4",
-// "tcp6", "unix" or "unixpacket".
-// For TCP and UDP, the syntax of laddr is "host:port", like "127.0.0.1:8080".
-// If host is omitted, as in ":8080", Listen listens on all available interfaces
-// instead of just the interface with the given host address.
-// See Dial for more details about address syntax.
+// Listen announces on the local network address.
 //
-// Listening on a hostname is not recommended because this creates a socket
-// for at most one of its IP addresses.
-func Listen(net, laddr string) (Listener, error) {
-	addrs, err := DefaultResolver.resolveAddrList(context.Background(), "listen", net, laddr, nil)
+// The network must be "tcp", "tcp4", "tcp6", "unix" or "unixpacket".
+//
+// For TCP networks, if the host in the address parameter is empty or
+// a literal unspecified IP address, Listen listens on all available
+// unicast and anycast IP addresses of the local system.
+// To only use IPv4, use network "tcp4".
+// The address can use a host name, but this is not recommended,
+// because it will create a listener for at most one of the host's IP
+// addresses.
+// If the port in the address parameter is empty or "0", as in
+// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
+// The Addr method of Listener can be used to discover the chosen
+// port.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func Listen(network, address string) (Listener, error) {
+	addrs, err := DefaultResolver.resolveAddrList(context.Background(), "listen", network, address, nil)
 	if err != nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: nil, Err: err}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
 	}
 	var l Listener
 	switch la := addrs.first(isIPv4).(type) {
 	case *TCPAddr:
-		l, err = ListenTCP(net, la)
+		l, err = ListenTCP(network, la)
 	case *UnixAddr:
-		l, err = ListenUnix(net, la)
+		l, err = ListenUnix(network, la)
 	default:
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: laddr}}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
 	}
 	if err != nil {
 		return nil, err // l is non-nil interface containing nil pointer
@@ -567,31 +601,43 @@
 	return l, nil
 }
 
-// ListenPacket announces on the local network address laddr.
-// The network net must be a packet-oriented network: "udp", "udp4",
-// "udp6", "ip", "ip4", "ip6" or "unixgram".
-// For TCP and UDP, the syntax of laddr is "host:port", like "127.0.0.1:8080".
-// If host is omitted, as in ":8080", ListenPacket listens on all available interfaces
-// instead of just the interface with the given host address.
-// See Dial for the syntax of laddr.
+// ListenPacket announces on the local network address.
 //
-// Listening on a hostname is not recommended because this creates a socket
-// for at most one of its IP addresses.
-func ListenPacket(net, laddr string) (PacketConn, error) {
-	addrs, err := DefaultResolver.resolveAddrList(context.Background(), "listen", net, laddr, nil)
+// The network must be "udp", "udp4", "udp6", "unixgram", or an IP
+// transport. The IP transports are "ip", "ip4", or "ip6" followed by
+// a colon and a literal protocol number or a protocol name, as in
+// "ip:1" or "ip:icmp".
+//
+// For UDP and IP networks, if the host in the address parameter is
+// empty or a literal unspecified IP address, ListenPacket listens on
+// all available IP addresses of the local system except multicast IP
+// addresses.
+// To only use IPv4, use network "udp4" or "ip4:proto".
+// The address can use a host name, but this is not recommended,
+// because it will create a listener for at most one of the host's IP
+// addresses.
+// If the port in the address parameter is empty or "0", as in
+// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
+// The LocalAddr method of PacketConn can be used to discover the
+// chosen port.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func ListenPacket(network, address string) (PacketConn, error) {
+	addrs, err := DefaultResolver.resolveAddrList(context.Background(), "listen", network, address, nil)
 	if err != nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: nil, Err: err}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
 	}
 	var l PacketConn
 	switch la := addrs.first(isIPv4).(type) {
 	case *UDPAddr:
-		l, err = ListenUDP(net, la)
+		l, err = ListenUDP(network, la)
 	case *IPAddr:
-		l, err = ListenIP(net, la)
+		l, err = ListenIP(network, la)
 	case *UnixAddr:
-		l, err = ListenUnixgram(net, la)
+		l, err = ListenUnixgram(network, la)
 	default:
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: laddr}}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
 	}
 	if err != nil {
 		return nil, err // l is non-nil interface containing nil pointer
diff --git a/libgo/go/net/dial_test.go b/libgo/go/net/dial_test.go
index 9919d72..a892bf1 100644
--- a/libgo/go/net/dial_test.go
+++ b/libgo/go/net/dial_test.go
@@ -7,9 +7,9 @@
 import (
 	"bufio"
 	"context"
+	"internal/poll"
 	"internal/testenv"
 	"io"
-	"net/internal/socktest"
 	"runtime"
 	"sync"
 	"testing"
@@ -31,7 +31,7 @@
 	case "plan9":
 		t.Skipf("not supported on %s", runtime.GOOS)
 	}
-	if !supportsIPv4map {
+	if !supportsIPv4map() {
 		t.Skip("mapping ipv4 address inside ipv6 address not supported")
 	}
 
@@ -72,70 +72,6 @@
 	c.Close()
 }
 
-func TestDialTimeoutFDLeak(t *testing.T) {
-	switch runtime.GOOS {
-	case "plan9":
-		t.Skipf("%s does not have full support of socktest", runtime.GOOS)
-	case "openbsd":
-		testenv.SkipFlaky(t, 15157)
-	}
-
-	const T = 100 * time.Millisecond
-
-	switch runtime.GOOS {
-	case "plan9", "windows":
-		origTestHookDialChannel := testHookDialChannel
-		testHookDialChannel = func() { time.Sleep(2 * T) }
-		defer func() { testHookDialChannel = origTestHookDialChannel }()
-		if runtime.GOOS == "plan9" {
-			break
-		}
-		fallthrough
-	default:
-		sw.Set(socktest.FilterConnect, func(so *socktest.Status) (socktest.AfterFilter, error) {
-			time.Sleep(2 * T)
-			return nil, errTimeout
-		})
-		defer sw.Set(socktest.FilterConnect, nil)
-	}
-
-	// Avoid tracking open-close jitterbugs between netFD and
-	// socket that leads to confusion of information inside
-	// socktest.Switch.
-	// It may happen when the Dial call bumps against TCP
-	// simultaneous open. See selfConnect in tcpsock_posix.go.
-	defer func() { sw.Set(socktest.FilterClose, nil) }()
-	var mu sync.Mutex
-	var attempts int
-	sw.Set(socktest.FilterClose, func(so *socktest.Status) (socktest.AfterFilter, error) {
-		mu.Lock()
-		attempts++
-		mu.Unlock()
-		return nil, nil
-	})
-
-	const N = 100
-	var wg sync.WaitGroup
-	wg.Add(N)
-	for i := 0; i < N; i++ {
-		go func() {
-			defer wg.Done()
-			// This dial never starts to send any SYN
-			// segment because of above socket filter and
-			// test hook.
-			c, err := DialTimeout("tcp", "127.0.0.1:0", T)
-			if err == nil {
-				t.Errorf("unexpectedly established: tcp:%s->%s", c.LocalAddr(), c.RemoteAddr())
-				c.Close()
-			}
-		}()
-	}
-	wg.Wait()
-	if attempts < N {
-		t.Errorf("got %d; want >= %d", attempts, N)
-	}
-}
-
 func TestDialerDualStackFDLeak(t *testing.T) {
 	switch runtime.GOOS {
 	case "plan9":
@@ -145,7 +81,7 @@
 	case "openbsd":
 		testenv.SkipFlaky(t, 15157)
 	}
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -254,7 +190,7 @@
 func TestDialParallel(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -425,7 +361,7 @@
 func TestDialerFallbackDelay(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -491,7 +427,7 @@
 }
 
 func TestDialParallelSpuriousConnection(t *testing.T) {
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -585,22 +521,22 @@
 		{now, noDeadline, 1, noDeadline, nil},
 		// Step the clock forward and cross the deadline.
 		{now.Add(-1 * time.Millisecond), now, 1, now, nil},
-		{now.Add(0 * time.Millisecond), now, 1, noDeadline, errTimeout},
-		{now.Add(1 * time.Millisecond), now, 1, noDeadline, errTimeout},
+		{now.Add(0 * time.Millisecond), now, 1, noDeadline, poll.ErrTimeout},
+		{now.Add(1 * time.Millisecond), now, 1, noDeadline, poll.ErrTimeout},
 	}
 	for i, tt := range testCases {
 		deadline, err := partialDeadline(tt.now, tt.deadline, tt.addrs)
 		if err != tt.expectErr {
 			t.Errorf("#%d: got %v; want %v", i, err, tt.expectErr)
 		}
-		if deadline != tt.expectDeadline {
+		if !deadline.Equal(tt.expectDeadline) {
 			t.Errorf("#%d: got %v; want %v", i, deadline, tt.expectDeadline)
 		}
 	}
 }
 
 func TestDialerLocalAddr(t *testing.T) {
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -654,7 +590,7 @@
 		{"tcp", "::1", &UnixAddr{}, &AddrError{Err: "some error"}},
 	}
 
-	if supportsIPv4map {
+	if supportsIPv4map() {
 		tests = append(tests, test{
 			"tcp", "127.0.0.1", &TCPAddr{IP: ParseIP("::")}, nil,
 		})
@@ -714,12 +650,9 @@
 }
 
 func TestDialerDualStack(t *testing.T) {
-	// This test is known to be flaky. Don't frighten regular
-	// users about it; only fail on the build dashboard.
-	if testenv.Builder() == "" {
-		testenv.SkipFlaky(t, 13324)
-	}
-	if !supportsIPv4 || !supportsIPv6 {
+	testenv.SkipFlaky(t, 13324)
+
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -822,7 +755,7 @@
 	}
 
 	blackholeIPPort := JoinHostPort(slowDst4, "1234")
-	if !supportsIPv4 {
+	if !supportsIPv4() {
 		blackholeIPPort = JoinHostPort(slowDst6, "1234")
 	}
 
@@ -954,3 +887,24 @@
 		try()
 	}
 }
+
+// Issue 18806: it should always be possible to net.Dial a
+// net.Listener().Addr().String when the listen address was ":n", even
+// if the machine has halfway configured IPv6 such that it can bind on
+// "::" not connect back to that same address.
+func TestDialListenerAddr(t *testing.T) {
+	if testenv.Builder() == "" {
+		testenv.MustHaveExternalNetwork(t)
+	}
+	ln, err := Listen("tcp", ":0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer ln.Close()
+	addr := ln.Addr().String()
+	c, err := Dial("tcp", addr)
+	if err != nil {
+		t.Fatalf("for addr %q, dial error: %v", addr, err)
+	}
+	c.Close()
+}
diff --git a/libgo/go/net/dnsclient_unix.go b/libgo/go/net/dnsclient_unix.go
index 0647b9c..ff6a4f6 100644
--- a/libgo/go/net/dnsclient_unix.go
+++ b/libgo/go/net/dnsclient_unix.go
@@ -25,13 +25,6 @@
 	"time"
 )
 
-// A dnsDialer provides dialing suitable for DNS queries.
-type dnsDialer interface {
-	dialDNS(ctx context.Context, network, addr string) (dnsConn, error)
-}
-
-var testHookDNSDialer = func() dnsDialer { return &Dialer{} }
-
 // A dnsConn represents a DNS transport endpoint.
 type dnsConn interface {
 	io.Closer
@@ -43,14 +36,14 @@
 	dnsRoundTrip(query *dnsMsg) (*dnsMsg, error)
 }
 
-func (c *UDPConn) dnsRoundTrip(query *dnsMsg) (*dnsMsg, error) {
-	return dnsRoundTripUDP(c, query)
+// dnsPacketConn implements the dnsConn interface for RFC 1035's
+// "UDP usage" transport mechanism. Conn is a packet-oriented connection,
+// such as a *UDPConn.
+type dnsPacketConn struct {
+	Conn
 }
 
-// dnsRoundTripUDP implements the dnsRoundTrip interface for RFC 1035's
-// "UDP usage" transport mechanism. c should be a packet-oriented connection,
-// such as a *UDPConn.
-func dnsRoundTripUDP(c io.ReadWriter, query *dnsMsg) (*dnsMsg, error) {
+func (c *dnsPacketConn) dnsRoundTrip(query *dnsMsg) (*dnsMsg, error) {
 	b, ok := query.Pack()
 	if !ok {
 		return nil, errors.New("cannot marshal DNS message")
@@ -76,14 +69,14 @@
 	}
 }
 
-func (c *TCPConn) dnsRoundTrip(out *dnsMsg) (*dnsMsg, error) {
-	return dnsRoundTripTCP(c, out)
+// dnsStreamConn implements the dnsConn interface for RFC 1035's
+// "TCP usage" transport mechanism. Conn is a stream-oriented connection,
+// such as a *TCPConn.
+type dnsStreamConn struct {
+	Conn
 }
 
-// dnsRoundTripTCP implements the dnsRoundTrip interface for RFC 1035's
-// "TCP usage" transport mechanism. c should be a stream-oriented connection,
-// such as a *TCPConn.
-func dnsRoundTripTCP(c io.ReadWriter, query *dnsMsg) (*dnsMsg, error) {
+func (c *dnsStreamConn) dnsRoundTrip(query *dnsMsg) (*dnsMsg, error) {
 	b, ok := query.Pack()
 	if !ok {
 		return nil, errors.New("cannot marshal DNS message")
@@ -116,33 +109,8 @@
 	return resp, nil
 }
 
-func (d *Dialer) dialDNS(ctx context.Context, network, server string) (dnsConn, error) {
-	switch network {
-	case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6":
-	default:
-		return nil, UnknownNetworkError(network)
-	}
-	// Calling Dial here is scary -- we have to be sure not to
-	// dial a name that will require a DNS lookup, or Dial will
-	// call back here to translate it. The DNS config parser has
-	// already checked that all the cfg.servers are IP
-	// addresses, which Dial will use without a DNS lookup.
-	c, err := d.DialContext(ctx, network, server)
-	if err != nil {
-		return nil, mapErr(err)
-	}
-	switch network {
-	case "tcp", "tcp4", "tcp6":
-		return c.(*TCPConn), nil
-	case "udp", "udp4", "udp6":
-		return c.(*UDPConn), nil
-	}
-	panic("unreachable")
-}
-
 // exchange sends a query on the connection and hopes for a response.
-func exchange(ctx context.Context, server, name string, qtype uint16, timeout time.Duration) (*dnsMsg, error) {
-	d := testHookDNSDialer()
+func (r *Resolver) exchange(ctx context.Context, server, name string, qtype uint16, timeout time.Duration) (*dnsMsg, error) {
 	out := dnsMsg{
 		dnsMsgHdr: dnsMsgHdr{
 			recursion_desired: true,
@@ -158,7 +126,7 @@
 		ctx, cancel := context.WithDeadline(ctx, time.Now().Add(timeout))
 		defer cancel()
 
-		c, err := d.dialDNS(ctx, network, server)
+		c, err := r.dial(ctx, network, server)
 		if err != nil {
 			return nil, err
 		}
@@ -181,7 +149,7 @@
 
 // Do a lookup for a single name, which must be rooted
 // (otherwise answer will not find the answers).
-func tryOneName(ctx context.Context, cfg *dnsConfig, name string, qtype uint16) (string, []dnsRR, error) {
+func (r *Resolver) tryOneName(ctx context.Context, cfg *dnsConfig, name string, qtype uint16) (string, []dnsRR, error) {
 	var lastErr error
 	serverOffset := cfg.serverOffset()
 	sLen := uint32(len(cfg.servers))
@@ -190,7 +158,7 @@
 		for j := uint32(0); j < sLen; j++ {
 			server := cfg.servers[(serverOffset+j)%sLen]
 
-			msg, err := exchange(ctx, server, name, qtype, cfg.timeout)
+			msg, err := r.exchange(ctx, server, name, qtype, cfg.timeout)
 			if err != nil {
 				lastErr = &DNSError{
 					Err:    err.Error(),
@@ -200,6 +168,11 @@
 				if nerr, ok := err.(Error); ok && nerr.Timeout() {
 					lastErr.(*DNSError).IsTimeout = true
 				}
+				// Set IsTemporary for socket-level errors. Note that this flag
+				// may also be used to indicate a SERVFAIL response.
+				if _, ok := err.(*OpError); ok {
+					lastErr.(*DNSError).IsTemporary = true
+				}
 				continue
 			}
 			// libresolv continues to the next server when it receives
@@ -314,7 +287,7 @@
 	<-conf.ch
 }
 
-func lookup(ctx context.Context, name string, qtype uint16) (cname string, rrs []dnsRR, err error) {
+func (r *Resolver) lookup(ctx context.Context, name string, qtype uint16) (cname string, rrs []dnsRR, err error) {
 	if !isDomainName(name) {
 		// We used to use "invalid domain name" as the error,
 		// but that is a detail of the specific lookup mechanism.
@@ -328,10 +301,15 @@
 	conf := resolvConf.dnsConfig
 	resolvConf.mu.RUnlock()
 	for _, fqdn := range conf.nameList(name) {
-		cname, rrs, err = tryOneName(ctx, conf, fqdn, qtype)
+		cname, rrs, err = r.tryOneName(ctx, conf, fqdn, qtype)
 		if err == nil {
 			break
 		}
+		if nerr, ok := err.(Error); ok && nerr.Temporary() && r.StrictErrors {
+			// If we hit a temporary error with StrictErrors enabled,
+			// stop immediately instead of trying more names.
+			break
+		}
 	}
 	if err, ok := err.(*DNSError); ok {
 		// Show original name passed to lookup, not suffixed one.
@@ -432,11 +410,11 @@
 // Normally we let cgo use the C library resolver instead of
 // depending on our lookup code, so that Go and C get the same
 // answers.
-func goLookupHost(ctx context.Context, name string) (addrs []string, err error) {
-	return goLookupHostOrder(ctx, name, hostLookupFilesDNS)
+func (r *Resolver) goLookupHost(ctx context.Context, name string) (addrs []string, err error) {
+	return r.goLookupHostOrder(ctx, name, hostLookupFilesDNS)
 }
 
-func goLookupHostOrder(ctx context.Context, name string, order hostLookupOrder) (addrs []string, err error) {
+func (r *Resolver) goLookupHostOrder(ctx context.Context, name string, order hostLookupOrder) (addrs []string, err error) {
 	if order == hostLookupFilesDNS || order == hostLookupFiles {
 		// Use entries from /etc/hosts if they match.
 		addrs = lookupStaticHost(name)
@@ -444,7 +422,7 @@
 			return
 		}
 	}
-	ips, _, err := goLookupIPCNAMEOrder(ctx, name, order)
+	ips, _, err := r.goLookupIPCNAMEOrder(ctx, name, order)
 	if err != nil {
 		return
 	}
@@ -470,13 +448,13 @@
 
 // goLookupIP is the native Go implementation of LookupIP.
 // The libc versions are in cgo_*.go.
-func goLookupIP(ctx context.Context, host string) (addrs []IPAddr, err error) {
+func (r *Resolver) goLookupIP(ctx context.Context, host string) (addrs []IPAddr, err error) {
 	order := systemConf().hostLookupOrder(host)
-	addrs, _, err = goLookupIPCNAMEOrder(ctx, host, order)
+	addrs, _, err = r.goLookupIPCNAMEOrder(ctx, host, order)
 	return
 }
 
-func goLookupIPCNAMEOrder(ctx context.Context, name string, order hostLookupOrder) (addrs []IPAddr, cname string, err error) {
+func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, name string, order hostLookupOrder) (addrs []IPAddr, cname string, err error) {
 	if order == hostLookupFilesDNS || order == hostLookupFiles {
 		addrs = goLookupIPFiles(name)
 		if len(addrs) > 0 || order == hostLookupFiles {
@@ -502,15 +480,20 @@
 	for _, fqdn := range conf.nameList(name) {
 		for _, qtype := range qtypes {
 			go func(qtype uint16) {
-				cname, rrs, err := tryOneName(ctx, conf, fqdn, qtype)
+				cname, rrs, err := r.tryOneName(ctx, conf, fqdn, qtype)
 				lane <- racer{cname, rrs, err}
 			}(qtype)
 		}
+		hitStrictError := false
 		for range qtypes {
 			racer := <-lane
 			if racer.error != nil {
-				// Prefer error for original name.
-				if lastErr == nil || fqdn == name+"." {
+				if nerr, ok := racer.error.(Error); ok && nerr.Temporary() && r.StrictErrors {
+					// This error will abort the nameList loop.
+					hitStrictError = true
+					lastErr = racer.error
+				} else if lastErr == nil || fqdn == name+"." {
+					// Prefer error for original name.
 					lastErr = racer.error
 				}
 				continue
@@ -520,6 +503,13 @@
 				cname = racer.cname
 			}
 		}
+		if hitStrictError {
+			// If either family hit an error with StrictErrors enabled,
+			// discard all addresses. This ensures that network flakiness
+			// cannot turn a dualstack hostname IPv4/IPv6-only.
+			addrs = nil
+			break
+		}
 		if len(addrs) > 0 {
 			break
 		}
@@ -543,9 +533,9 @@
 }
 
 // goLookupCNAME is the native Go (non-cgo) implementation of LookupCNAME.
-func goLookupCNAME(ctx context.Context, host string) (cname string, err error) {
+func (r *Resolver) goLookupCNAME(ctx context.Context, host string) (cname string, err error) {
 	order := systemConf().hostLookupOrder(host)
-	_, cname, err = goLookupIPCNAMEOrder(ctx, host, order)
+	_, cname, err = r.goLookupIPCNAMEOrder(ctx, host, order)
 	return
 }
 
@@ -554,7 +544,7 @@
 // only if cgoLookupPTR is the stub in cgo_stub.go).
 // Normally we let cgo use the C library resolver instead of depending
 // on our lookup code, so that Go and C get the same answers.
-func goLookupPTR(ctx context.Context, addr string) ([]string, error) {
+func (r *Resolver) goLookupPTR(ctx context.Context, addr string) ([]string, error) {
 	names := lookupStaticAddr(addr)
 	if len(names) > 0 {
 		return names, nil
@@ -563,7 +553,7 @@
 	if err != nil {
 		return nil, err
 	}
-	_, rrs, err := lookup(ctx, arpa, dnsTypePTR)
+	_, rrs, err := r.lookup(ctx, arpa, dnsTypePTR)
 	if err != nil {
 		return nil, err
 	}
diff --git a/libgo/go/net/dnsclient_unix_test.go b/libgo/go/net/dnsclient_unix_test.go
index c66d2d1..94811c9 100644
--- a/libgo/go/net/dnsclient_unix_test.go
+++ b/libgo/go/net/dnsclient_unix_test.go
@@ -8,8 +8,9 @@
 
 import (
 	"context"
+	"errors"
 	"fmt"
-	"internal/testenv"
+	"internal/poll"
 	"io/ioutil"
 	"os"
 	"path"
@@ -20,9 +21,14 @@
 	"time"
 )
 
+var goResolver = Resolver{PreferGo: true}
+
 // Test address from 192.0.2.0/24 block, reserved by RFC 5737 for documentation.
 const TestAddr uint32 = 0xc0000201
 
+// Test address from 2001:db8::/32 block, reserved by RFC 3849 for documentation.
+var TestAddr6 = [16]byte{0x20, 0x01, 0x0d, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
+
 var dnsTransportFallbackTests = []struct {
 	server  string
 	name    string
@@ -37,18 +43,33 @@
 }
 
 func TestDNSTransportFallback(t *testing.T) {
-	testenv.MustHaveExternalNetwork(t)
-
+	fake := fakeDNSServer{
+		rh: func(n, _ string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
+			r := &dnsMsg{
+				dnsMsgHdr: dnsMsgHdr{
+					id:       q.id,
+					response: true,
+					rcode:    dnsRcodeSuccess,
+				},
+				question: q.question,
+			}
+			if n == "udp" {
+				r.truncated = true
+			}
+			return r, nil
+		},
+	}
+	r := Resolver{PreferGo: true, Dial: fake.DialContext}
 	for _, tt := range dnsTransportFallbackTests {
 		ctx, cancel := context.WithCancel(context.Background())
 		defer cancel()
-		msg, err := exchange(ctx, tt.server, tt.name, tt.qtype, time.Second)
+		msg, err := r.exchange(ctx, tt.server, tt.name, tt.qtype, time.Second)
 		if err != nil {
 			t.Error(err)
 			continue
 		}
 		switch msg.rcode {
-		case tt.rcode, dnsRcodeServerFailure:
+		case tt.rcode:
 		default:
 			t.Errorf("got %v from %v; want %v", msg.rcode, tt.server, tt.rcode)
 			continue
@@ -78,13 +99,30 @@
 }
 
 func TestSpecialDomainName(t *testing.T) {
-	testenv.MustHaveExternalNetwork(t)
+	fake := fakeDNSServer{func(_, _ string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
+		r := &dnsMsg{
+			dnsMsgHdr: dnsMsgHdr{
+				id:       q.id,
+				response: true,
+			},
+			question: q.question,
+		}
 
+		switch q.question[0].Name {
+		case "example.com.":
+			r.rcode = dnsRcodeSuccess
+		default:
+			r.rcode = dnsRcodeNameError
+		}
+
+		return r, nil
+	}}
+	r := Resolver{PreferGo: true, Dial: fake.DialContext}
 	server := "8.8.8.8:53"
 	for _, tt := range specialDomainNameTests {
 		ctx, cancel := context.WithCancel(context.Background())
 		defer cancel()
-		msg, err := exchange(ctx, server, tt.name, tt.qtype, 3*time.Second)
+		msg, err := r.exchange(ctx, server, tt.name, tt.qtype, 3*time.Second)
 		if err != nil {
 			t.Error(err)
 			continue
@@ -139,15 +177,40 @@
 	}
 }
 
+var fakeDNSServerSuccessful = fakeDNSServer{func(_, _ string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
+	r := &dnsMsg{
+		dnsMsgHdr: dnsMsgHdr{
+			id:       q.id,
+			response: true,
+		},
+		question: q.question,
+	}
+	if len(q.question) == 1 && q.question[0].Qtype == dnsTypeA {
+		r.answer = []dnsRR{
+			&dnsRR_A{
+				Hdr: dnsRR_Header{
+					Name:     q.question[0].Name,
+					Rrtype:   dnsTypeA,
+					Class:    dnsClassINET,
+					Rdlength: 4,
+				},
+				A: TestAddr,
+			},
+		}
+	}
+	return r, nil
+}}
+
 // Issue 13705: don't try to resolve onion addresses, etc
 func TestLookupTorOnion(t *testing.T) {
-	addrs, err := goLookupIP(context.Background(), "foo.onion")
-	if len(addrs) > 0 {
-		t.Errorf("unexpected addresses: %v", addrs)
-	}
+	r := Resolver{PreferGo: true, Dial: fakeDNSServerSuccessful.DialContext}
+	addrs, err := r.LookupIPAddr(context.Background(), "foo.onion")
 	if err != nil {
 		t.Fatalf("lookup = %v; want nil", err)
 	}
+	if len(addrs) > 0 {
+		t.Errorf("unexpected addresses: %v", addrs)
+	}
 }
 
 type resolvConfTest struct {
@@ -237,7 +300,7 @@
 }
 
 func TestUpdateResolvConf(t *testing.T) {
-	testenv.MustHaveExternalNetwork(t)
+	r := Resolver{PreferGo: true, Dial: fakeDNSServerSuccessful.DialContext}
 
 	conf, err := newResolvConfTest()
 	if err != nil {
@@ -257,7 +320,7 @@
 			for j := 0; j < N; j++ {
 				go func(name string) {
 					defer wg.Done()
-					ips, err := goLookupIP(context.Background(), name)
+					ips, err := r.LookupIPAddr(context.Background(), name)
 					if err != nil {
 						t.Error(err)
 						return
@@ -392,7 +455,60 @@
 }
 
 func TestGoLookupIPWithResolverConfig(t *testing.T) {
-	testenv.MustHaveExternalNetwork(t)
+	fake := fakeDNSServer{func(n, s string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
+		switch s {
+		case "[2001:4860:4860::8888]:53", "8.8.8.8:53":
+			break
+		default:
+			time.Sleep(10 * time.Millisecond)
+			return nil, poll.ErrTimeout
+		}
+		r := &dnsMsg{
+			dnsMsgHdr: dnsMsgHdr{
+				id:       q.id,
+				response: true,
+			},
+			question: q.question,
+		}
+		for _, question := range q.question {
+			switch question.Qtype {
+			case dnsTypeA:
+				switch question.Name {
+				case "hostname.as112.net.":
+					break
+				case "ipv4.google.com.":
+					r.answer = append(r.answer, &dnsRR_A{
+						Hdr: dnsRR_Header{
+							Name:     q.question[0].Name,
+							Rrtype:   dnsTypeA,
+							Class:    dnsClassINET,
+							Rdlength: 4,
+						},
+						A: TestAddr,
+					})
+				default:
+
+				}
+			case dnsTypeAAAA:
+				switch question.Name {
+				case "hostname.as112.net.":
+					break
+				case "ipv6.google.com.":
+					r.answer = append(r.answer, &dnsRR_AAAA{
+						Hdr: dnsRR_Header{
+							Name:     q.question[0].Name,
+							Rrtype:   dnsTypeAAAA,
+							Class:    dnsClassINET,
+							Rdlength: 16,
+						},
+						AAAA: TestAddr6,
+					})
+				}
+			}
+		}
+		return r, nil
+	}}
+	r := Resolver{PreferGo: true, Dial: fake.DialContext}
 
 	conf, err := newResolvConfTest()
 	if err != nil {
@@ -405,14 +521,8 @@
 			t.Error(err)
 			continue
 		}
-		addrs, err := goLookupIP(context.Background(), tt.name)
+		addrs, err := r.LookupIPAddr(context.Background(), tt.name)
 		if err != nil {
-			// This test uses external network connectivity.
-			// We need to take care with errors on both
-			// DNS message exchange layer and DNS
-			// transport layer because goLookupIP may fail
-			// when the IP connectivity on node under test
-			// gets lost during its run.
 			if err, ok := err.(*DNSError); !ok || tt.error != nil && (err.Name != tt.error.(*DNSError).Name || err.Server != tt.error.(*DNSError).Server || err.IsTimeout != tt.error.(*DNSError).IsTimeout) {
 				t.Errorf("got %v; want %v", err, tt.error)
 			}
@@ -437,7 +547,17 @@
 
 // Test that goLookupIPOrder falls back to the host file when no DNS servers are available.
 func TestGoLookupIPOrderFallbackToFile(t *testing.T) {
-	testenv.MustHaveExternalNetwork(t)
+	fake := fakeDNSServer{func(n, s string, q *dnsMsg, tm time.Time) (*dnsMsg, error) {
+		r := &dnsMsg{
+			dnsMsgHdr: dnsMsgHdr{
+				id:       q.id,
+				response: true,
+			},
+			question: q.question,
+		}
+		return r, nil
+	}}
+	r := Resolver{PreferGo: true, Dial: fake.DialContext}
 
 	// Add a config that simulates no dns servers being available.
 	conf, err := newResolvConfTest()
@@ -455,14 +575,14 @@
 		name := fmt.Sprintf("order %v", order)
 
 		// First ensure that we get an error when contacting a non-existent host.
-		_, _, err := goLookupIPCNAMEOrder(context.Background(), "notarealhost", order)
+		_, _, err := r.goLookupIPCNAMEOrder(context.Background(), "notarealhost", order)
 		if err == nil {
 			t.Errorf("%s: expected error while looking up name not in hosts file", name)
 			continue
 		}
 
 		// Now check that we get an address when the name appears in the hosts file.
-		addrs, _, err := goLookupIPCNAMEOrder(context.Background(), "thor", order) // entry is in "testdata/hosts"
+		addrs, _, err := r.goLookupIPCNAMEOrder(context.Background(), "thor", order) // entry is in "testdata/hosts"
 		if err != nil {
 			t.Errorf("%s: expected to successfully lookup host entry", name)
 			continue
@@ -485,9 +605,6 @@
 func TestErrorForOriginalNameWhenSearching(t *testing.T) {
 	const fqdn = "doesnotexist.domain"
 
-	origTestHookDNSDialer := testHookDNSDialer
-	defer func() { testHookDNSDialer = origTestHookDNSDialer }()
-
 	conf, err := newResolvConfTest()
 	if err != nil {
 		t.Fatal(err)
@@ -498,14 +615,13 @@
 		t.Fatal(err)
 	}
 
-	d := &fakeDNSDialer{}
-	testHookDNSDialer = func() dnsDialer { return d }
-
-	d.rh = func(s string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
+	fake := fakeDNSServer{func(_, _ string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
 		r := &dnsMsg{
 			dnsMsgHdr: dnsMsgHdr{
-				id: q.id,
+				id:       q.id,
+				response: true,
 			},
+			question: q.question,
 		}
 
 		switch q.question[0].Name {
@@ -516,24 +632,31 @@
 		}
 
 		return r, nil
-	}
+	}}
 
-	_, err = goLookupIP(context.Background(), fqdn)
-	if err == nil {
-		t.Fatal("expected an error")
+	cases := []struct {
+		strictErrors bool
+		wantErr      *DNSError
+	}{
+		{true, &DNSError{Name: fqdn, Err: "server misbehaving", IsTemporary: true}},
+		{false, &DNSError{Name: fqdn, Err: errNoSuchHost.Error()}},
 	}
+	for _, tt := range cases {
+		r := Resolver{PreferGo: true, StrictErrors: tt.strictErrors, Dial: fake.DialContext}
+		_, err = r.LookupIPAddr(context.Background(), fqdn)
+		if err == nil {
+			t.Fatal("expected an error")
+		}
 
-	want := &DNSError{Name: fqdn, Err: errNoSuchHost.Error()}
-	if err, ok := err.(*DNSError); !ok || err.Name != want.Name || err.Err != want.Err {
-		t.Errorf("got %v; want %v", err, want)
+		want := tt.wantErr
+		if err, ok := err.(*DNSError); !ok || err.Name != want.Name || err.Err != want.Err || err.IsTemporary != want.IsTemporary {
+			t.Errorf("got %v; want %v", err, want)
+		}
 	}
 }
 
 // Issue 15434. If a name server gives a lame referral, continue to the next.
 func TestIgnoreLameReferrals(t *testing.T) {
-	origTestHookDNSDialer := testHookDNSDialer
-	defer func() { testHookDNSDialer = origTestHookDNSDialer }()
-
 	conf, err := newResolvConfTest()
 	if err != nil {
 		t.Fatal(err)
@@ -545,10 +668,7 @@
 		t.Fatal(err)
 	}
 
-	d := &fakeDNSDialer{}
-	testHookDNSDialer = func() dnsDialer { return d }
-
-	d.rh = func(s string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
+	fake := fakeDNSServer{func(_, s string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
 		t.Log(s, q)
 		r := &dnsMsg{
 			dnsMsgHdr: dnsMsgHdr{
@@ -576,9 +696,10 @@
 		}
 
 		return r, nil
-	}
+	}}
+	r := Resolver{PreferGo: true, Dial: fake.DialContext}
 
-	addrs, err := goLookupIP(context.Background(), "www.golang.org")
+	addrs, err := r.LookupIPAddr(context.Background(), "www.golang.org")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -597,7 +718,7 @@
 	ctx := context.Background()
 
 	for i := 0; i < b.N; i++ {
-		goLookupIP(ctx, "www.example.com")
+		goResolver.LookupIPAddr(ctx, "www.example.com")
 	}
 }
 
@@ -606,7 +727,7 @@
 	ctx := context.Background()
 
 	for i := 0; i < b.N; i++ {
-		goLookupIP(ctx, "some.nonexistent")
+		goResolver.LookupIPAddr(ctx, "some.nonexistent")
 	}
 }
 
@@ -629,38 +750,70 @@
 	ctx := context.Background()
 
 	for i := 0; i < b.N; i++ {
-		goLookupIP(ctx, "www.example.com")
+		goResolver.LookupIPAddr(ctx, "www.example.com")
 	}
 }
 
-type fakeDNSDialer struct {
-	// reply handler
-	rh func(s string, q *dnsMsg, t time.Time) (*dnsMsg, error)
+type fakeDNSServer struct {
+	rh func(n, s string, q *dnsMsg, t time.Time) (*dnsMsg, error)
 }
 
-func (f *fakeDNSDialer) dialDNS(_ context.Context, n, s string) (dnsConn, error) {
-	return &fakeDNSConn{f.rh, s, time.Time{}}, nil
+func (server *fakeDNSServer) DialContext(_ context.Context, n, s string) (Conn, error) {
+	return &fakeDNSConn{nil, server, n, s, nil, time.Time{}}, nil
 }
 
 type fakeDNSConn struct {
-	rh func(s string, q *dnsMsg, t time.Time) (*dnsMsg, error)
-	s  string
-	t  time.Time
+	Conn
+	server *fakeDNSServer
+	n      string
+	s      string
+	q      *dnsMsg
+	t      time.Time
 }
 
 func (f *fakeDNSConn) Close() error {
 	return nil
 }
 
+func (f *fakeDNSConn) Read(b []byte) (int, error) {
+	resp, err := f.server.rh(f.n, f.s, f.q, f.t)
+	if err != nil {
+		return 0, err
+	}
+
+	bb, ok := resp.Pack()
+	if !ok {
+		return 0, errors.New("cannot marshal DNS message")
+	}
+	if len(b) < len(bb) {
+		return 0, errors.New("read would fragment DNS message")
+	}
+
+	copy(b, bb)
+	return len(bb), nil
+}
+
+func (f *fakeDNSConn) ReadFrom(b []byte) (int, Addr, error) {
+	return 0, nil, nil
+}
+
+func (f *fakeDNSConn) Write(b []byte) (int, error) {
+	f.q = new(dnsMsg)
+	if !f.q.Unpack(b) {
+		return 0, errors.New("cannot unmarshal DNS message")
+	}
+	return len(b), nil
+}
+
+func (f *fakeDNSConn) WriteTo(b []byte, addr Addr) (int, error) {
+	return 0, nil
+}
+
 func (f *fakeDNSConn) SetDeadline(t time.Time) error {
 	f.t = t
 	return nil
 }
 
-func (f *fakeDNSConn) dnsRoundTrip(q *dnsMsg) (*dnsMsg, error) {
-	return f.rh(f.s, q, f.t)
-}
-
 // UDP round-tripper algorithm should ignore invalid DNS responses (issue 13281).
 func TestIgnoreDNSForgeries(t *testing.T) {
 	c, s := Pipe()
@@ -723,7 +876,8 @@
 		},
 	}
 
-	resp, err := dnsRoundTripUDP(c, msg)
+	dc := &dnsPacketConn{c}
+	resp, err := dc.dnsRoundTrip(msg)
 	if err != nil {
 		t.Fatalf("dnsRoundTripUDP failed: %v", err)
 	}
@@ -735,9 +889,6 @@
 
 // Issue 16865. If a name server times out, continue to the next.
 func TestRetryTimeout(t *testing.T) {
-	origTestHookDNSDialer := testHookDNSDialer
-	defer func() { testHookDNSDialer = origTestHookDNSDialer }()
-
 	conf, err := newResolvConfTest()
 	if err != nil {
 		t.Fatal(err)
@@ -752,12 +903,9 @@
 		t.Fatal(err)
 	}
 
-	d := &fakeDNSDialer{}
-	testHookDNSDialer = func() dnsDialer { return d }
-
 	var deadline0 time.Time
 
-	d.rh = func(s string, q *dnsMsg, deadline time.Time) (*dnsMsg, error) {
+	fake := fakeDNSServer{func(_, s string, q *dnsMsg, deadline time.Time) (*dnsMsg, error) {
 		t.Log(s, q, deadline)
 
 		if deadline.IsZero() {
@@ -767,17 +915,18 @@
 		if s == "192.0.2.1:53" {
 			deadline0 = deadline
 			time.Sleep(10 * time.Millisecond)
-			return nil, errTimeout
+			return nil, poll.ErrTimeout
 		}
 
-		if deadline == deadline0 {
+		if deadline.Equal(deadline0) {
 			t.Error("deadline didn't change")
 		}
 
 		return mockTXTResponse(q), nil
-	}
+	}}
+	r := &Resolver{PreferGo: true, Dial: fake.DialContext}
 
-	_, err = LookupTXT("www.golang.org")
+	_, err = r.LookupTXT(context.Background(), "www.golang.org")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -796,9 +945,6 @@
 }
 
 func testRotate(t *testing.T, rotate bool, nameservers, wantServers []string) {
-	origTestHookDNSDialer := testHookDNSDialer
-	defer func() { testHookDNSDialer = origTestHookDNSDialer }()
-
 	conf, err := newResolvConfTest()
 	if err != nil {
 		t.Fatal(err)
@@ -817,18 +963,16 @@
 		t.Fatal(err)
 	}
 
-	d := &fakeDNSDialer{}
-	testHookDNSDialer = func() dnsDialer { return d }
-
 	var usedServers []string
-	d.rh = func(s string, q *dnsMsg, _ time.Time) (*dnsMsg, error) {
+	fake := fakeDNSServer{func(_, s string, q *dnsMsg, deadline time.Time) (*dnsMsg, error) {
 		usedServers = append(usedServers, s)
 		return mockTXTResponse(q), nil
-	}
+	}}
+	r := Resolver{PreferGo: true, Dial: fake.DialContext}
 
 	// len(nameservers) + 1 to allow rotation to get back to start
 	for i := 0; i < len(nameservers)+1; i++ {
-		if _, err := LookupTXT("www.golang.org"); err != nil {
+		if _, err := r.LookupTXT(context.Background(), "www.golang.org"); err != nil {
 			t.Fatal(err)
 		}
 	}
@@ -860,3 +1004,311 @@
 
 	return r
 }
+
+// Issue 17448. With StrictErrors enabled, temporary errors should make
+// LookupIP fail rather than return a partial result.
+func TestStrictErrorsLookupIP(t *testing.T) {
+	conf, err := newResolvConfTest()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conf.teardown()
+
+	confData := []string{
+		"nameserver 192.0.2.53",
+		"search x.golang.org y.golang.org",
+	}
+	if err := conf.writeAndUpdate(confData); err != nil {
+		t.Fatal(err)
+	}
+
+	const name = "test-issue19592"
+	const server = "192.0.2.53:53"
+	const searchX = "test-issue19592.x.golang.org."
+	const searchY = "test-issue19592.y.golang.org."
+	const ip4 = "192.0.2.1"
+	const ip6 = "2001:db8::1"
+
+	type resolveWhichEnum int
+	const (
+		resolveOK resolveWhichEnum = iota
+		resolveOpError
+		resolveServfail
+		resolveTimeout
+	)
+
+	makeTempError := func(err string) error {
+		return &DNSError{
+			Err:         err,
+			Name:        name,
+			Server:      server,
+			IsTemporary: true,
+		}
+	}
+	makeTimeout := func() error {
+		return &DNSError{
+			Err:       poll.ErrTimeout.Error(),
+			Name:      name,
+			Server:    server,
+			IsTimeout: true,
+		}
+	}
+	makeNxDomain := func() error {
+		return &DNSError{
+			Err:    errNoSuchHost.Error(),
+			Name:   name,
+			Server: server,
+		}
+	}
+
+	cases := []struct {
+		desc          string
+		resolveWhich  func(quest *dnsQuestion) resolveWhichEnum
+		wantStrictErr error
+		wantLaxErr    error
+		wantIPs       []string
+	}{
+		{
+			desc: "No errors",
+			resolveWhich: func(quest *dnsQuestion) resolveWhichEnum {
+				return resolveOK
+			},
+			wantIPs: []string{ip4, ip6},
+		},
+		{
+			desc: "searchX error fails in strict mode",
+			resolveWhich: func(quest *dnsQuestion) resolveWhichEnum {
+				if quest.Name == searchX {
+					return resolveTimeout
+				}
+				return resolveOK
+			},
+			wantStrictErr: makeTimeout(),
+			wantIPs:       []string{ip4, ip6},
+		},
+		{
+			desc: "searchX IPv4-only timeout fails in strict mode",
+			resolveWhich: func(quest *dnsQuestion) resolveWhichEnum {
+				if quest.Name == searchX && quest.Qtype == dnsTypeA {
+					return resolveTimeout
+				}
+				return resolveOK
+			},
+			wantStrictErr: makeTimeout(),
+			wantIPs:       []string{ip4, ip6},
+		},
+		{
+			desc: "searchX IPv6-only servfail fails in strict mode",
+			resolveWhich: func(quest *dnsQuestion) resolveWhichEnum {
+				if quest.Name == searchX && quest.Qtype == dnsTypeAAAA {
+					return resolveServfail
+				}
+				return resolveOK
+			},
+			wantStrictErr: makeTempError("server misbehaving"),
+			wantIPs:       []string{ip4, ip6},
+		},
+		{
+			desc: "searchY error always fails",
+			resolveWhich: func(quest *dnsQuestion) resolveWhichEnum {
+				if quest.Name == searchY {
+					return resolveTimeout
+				}
+				return resolveOK
+			},
+			wantStrictErr: makeTimeout(),
+			wantLaxErr:    makeNxDomain(), // This one reaches the "test." FQDN.
+		},
+		{
+			desc: "searchY IPv4-only socket error fails in strict mode",
+			resolveWhich: func(quest *dnsQuestion) resolveWhichEnum {
+				if quest.Name == searchY && quest.Qtype == dnsTypeA {
+					return resolveOpError
+				}
+				return resolveOK
+			},
+			wantStrictErr: makeTempError("write: socket on fire"),
+			wantIPs:       []string{ip6},
+		},
+		{
+			desc: "searchY IPv6-only timeout fails in strict mode",
+			resolveWhich: func(quest *dnsQuestion) resolveWhichEnum {
+				if quest.Name == searchY && quest.Qtype == dnsTypeAAAA {
+					return resolveTimeout
+				}
+				return resolveOK
+			},
+			wantStrictErr: makeTimeout(),
+			wantIPs:       []string{ip4},
+		},
+	}
+
+	for i, tt := range cases {
+		fake := fakeDNSServer{func(_, s string, q *dnsMsg, deadline time.Time) (*dnsMsg, error) {
+			t.Log(s, q)
+
+			switch tt.resolveWhich(&q.question[0]) {
+			case resolveOK:
+				// Handle below.
+			case resolveOpError:
+				return nil, &OpError{Op: "write", Err: fmt.Errorf("socket on fire")}
+			case resolveServfail:
+				return &dnsMsg{
+					dnsMsgHdr: dnsMsgHdr{
+						id:       q.id,
+						response: true,
+						rcode:    dnsRcodeServerFailure,
+					},
+					question: q.question,
+				}, nil
+			case resolveTimeout:
+				return nil, poll.ErrTimeout
+			default:
+				t.Fatal("Impossible resolveWhich")
+			}
+
+			switch q.question[0].Name {
+			case searchX, name + ".":
+				// Return NXDOMAIN to utilize the search list.
+				return &dnsMsg{
+					dnsMsgHdr: dnsMsgHdr{
+						id:       q.id,
+						response: true,
+						rcode:    dnsRcodeNameError,
+					},
+					question: q.question,
+				}, nil
+			case searchY:
+				// Return records below.
+			default:
+				return nil, fmt.Errorf("Unexpected Name: %v", q.question[0].Name)
+			}
+
+			r := &dnsMsg{
+				dnsMsgHdr: dnsMsgHdr{
+					id:       q.id,
+					response: true,
+				},
+				question: q.question,
+			}
+			switch q.question[0].Qtype {
+			case dnsTypeA:
+				r.answer = []dnsRR{
+					&dnsRR_A{
+						Hdr: dnsRR_Header{
+							Name:     q.question[0].Name,
+							Rrtype:   dnsTypeA,
+							Class:    dnsClassINET,
+							Rdlength: 4,
+						},
+						A: TestAddr,
+					},
+				}
+			case dnsTypeAAAA:
+				r.answer = []dnsRR{
+					&dnsRR_AAAA{
+						Hdr: dnsRR_Header{
+							Name:     q.question[0].Name,
+							Rrtype:   dnsTypeAAAA,
+							Class:    dnsClassINET,
+							Rdlength: 16,
+						},
+						AAAA: TestAddr6,
+					},
+				}
+			default:
+				return nil, fmt.Errorf("Unexpected Qtype: %v", q.question[0].Qtype)
+			}
+			return r, nil
+		}}
+
+		for _, strict := range []bool{true, false} {
+			r := Resolver{PreferGo: true, StrictErrors: strict, Dial: fake.DialContext}
+			ips, err := r.LookupIPAddr(context.Background(), name)
+
+			var wantErr error
+			if strict {
+				wantErr = tt.wantStrictErr
+			} else {
+				wantErr = tt.wantLaxErr
+			}
+			if !reflect.DeepEqual(err, wantErr) {
+				t.Errorf("#%d (%s) strict=%v: got err %#v; want %#v", i, tt.desc, strict, err, wantErr)
+			}
+
+			gotIPs := map[string]struct{}{}
+			for _, ip := range ips {
+				gotIPs[ip.String()] = struct{}{}
+			}
+			wantIPs := map[string]struct{}{}
+			if wantErr == nil {
+				for _, ip := range tt.wantIPs {
+					wantIPs[ip] = struct{}{}
+				}
+			}
+			if !reflect.DeepEqual(gotIPs, wantIPs) {
+				t.Errorf("#%d (%s) strict=%v: got ips %v; want %v", i, tt.desc, strict, gotIPs, wantIPs)
+			}
+		}
+	}
+}
+
+// Issue 17448. With StrictErrors enabled, temporary errors should make
+// LookupTXT stop walking the search list.
+func TestStrictErrorsLookupTXT(t *testing.T) {
+	conf, err := newResolvConfTest()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conf.teardown()
+
+	confData := []string{
+		"nameserver 192.0.2.53",
+		"search x.golang.org y.golang.org",
+	}
+	if err := conf.writeAndUpdate(confData); err != nil {
+		t.Fatal(err)
+	}
+
+	const name = "test"
+	const server = "192.0.2.53:53"
+	const searchX = "test.x.golang.org."
+	const searchY = "test.y.golang.org."
+	const txt = "Hello World"
+
+	fake := fakeDNSServer{func(_, s string, q *dnsMsg, deadline time.Time) (*dnsMsg, error) {
+		t.Log(s, q)
+
+		switch q.question[0].Name {
+		case searchX:
+			return nil, poll.ErrTimeout
+		case searchY:
+			return mockTXTResponse(q), nil
+		default:
+			return nil, fmt.Errorf("Unexpected Name: %v", q.question[0].Name)
+		}
+	}}
+
+	for _, strict := range []bool{true, false} {
+		r := Resolver{StrictErrors: strict, Dial: fake.DialContext}
+		_, rrs, err := r.lookup(context.Background(), name, dnsTypeTXT)
+		var wantErr error
+		var wantRRs int
+		if strict {
+			wantErr = &DNSError{
+				Err:       poll.ErrTimeout.Error(),
+				Name:      name,
+				Server:    server,
+				IsTimeout: true,
+			}
+		} else {
+			wantRRs = 1
+		}
+		if !reflect.DeepEqual(err, wantErr) {
+			t.Errorf("strict=%v: got err %#v; want %#v", strict, err, wantErr)
+		}
+		if len(rrs) != wantRRs {
+			t.Errorf("strict=%v: got %v; want %v", strict, len(rrs), wantRRs)
+		}
+	}
+}
diff --git a/libgo/go/net/error_posix.go b/libgo/go/net/error_posix.go
new file mode 100644
index 0000000..dd9754c
--- /dev/null
+++ b/libgo/go/net/error_posix.go
@@ -0,0 +1,21 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
+
+package net
+
+import (
+	"os"
+	"syscall"
+)
+
+// wrapSyscallError takes an error and a syscall name. If the error is
+// a syscall.Errno, it wraps it in a os.SyscallError using the syscall name.
+func wrapSyscallError(name string, err error) error {
+	if _, ok := err.(syscall.Errno); ok {
+		err = os.NewSyscallError(name, err)
+	}
+	return err
+}
diff --git a/libgo/go/net/error_test.go b/libgo/go/net/error_test.go
index c23da49..9791e6f 100644
--- a/libgo/go/net/error_test.go
+++ b/libgo/go/net/error_test.go
@@ -7,11 +7,13 @@
 import (
 	"context"
 	"fmt"
+	"internal/poll"
 	"io"
 	"io/ioutil"
 	"net/internal/socktest"
 	"os"
 	"runtime"
+	"strings"
 	"testing"
 	"time"
 )
@@ -87,7 +89,7 @@
 		return nil
 	}
 	switch err := nestedErr.(type) {
-	case *AddrError, addrinfoErrno, *DNSError, InvalidAddrError, *ParseError, *timeoutError, UnknownNetworkError:
+	case *AddrError, addrinfoErrno, *DNSError, InvalidAddrError, *ParseError, *poll.TimeoutError, UnknownNetworkError:
 		return nil
 	case *os.SyscallError:
 		nestedErr = err.Err
@@ -97,7 +99,7 @@
 		goto third
 	}
 	switch nestedErr {
-	case errCanceled, errClosing, errMissingAddress, errNoSuitableAddress,
+	case errCanceled, poll.ErrNetClosing, errMissingAddress, errNoSuitableAddress,
 		context.DeadlineExceeded, context.Canceled:
 		return nil
 	}
@@ -213,7 +215,7 @@
 	case "nacl", "plan9":
 		t.Skipf("not supported on %s", runtime.GOOS)
 	}
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -432,7 +434,7 @@
 		goto third
 	}
 	switch nestedErr {
-	case errClosing, errTimeout:
+	case poll.ErrNetClosing, poll.ErrTimeout:
 		return nil
 	}
 	return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
@@ -467,14 +469,14 @@
 		return nil
 	}
 	switch err := nestedErr.(type) {
-	case *AddrError, addrinfoErrno, *DNSError, InvalidAddrError, *ParseError, *timeoutError, UnknownNetworkError:
+	case *AddrError, addrinfoErrno, *DNSError, InvalidAddrError, *ParseError, *poll.TimeoutError, UnknownNetworkError:
 		return nil
 	case *os.SyscallError:
 		nestedErr = err.Err
 		goto third
 	}
 	switch nestedErr {
-	case errCanceled, errClosing, errMissingAddress, errTimeout, ErrWriteToConnected, io.ErrUnexpectedEOF:
+	case errCanceled, poll.ErrNetClosing, errMissingAddress, poll.ErrTimeout, ErrWriteToConnected, io.ErrUnexpectedEOF:
 		return nil
 	}
 	return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
@@ -489,11 +491,21 @@
 // parseCloseError parses nestedErr and reports whether it is a valid
 // error value from Close functions.
 // It returns nil when nestedErr is valid.
-func parseCloseError(nestedErr error) error {
+func parseCloseError(nestedErr error, isShutdown bool) error {
 	if nestedErr == nil {
 		return nil
 	}
 
+	// Because historically we have not exported the error that we
+	// return for an operation on a closed network connection,
+	// there are programs that test for the exact error string.
+	// Verify that string here so that we don't break those
+	// programs unexpectedly. See issues #4373 and #19252.
+	want := "use of closed network connection"
+	if !isShutdown && !strings.Contains(nestedErr.Error(), want) {
+		return fmt.Errorf("error string %q does not contain expected string %q", nestedErr, want)
+	}
+
 	switch err := nestedErr.(type) {
 	case *OpError:
 		if err := err.isValid(); err != nil {
@@ -517,7 +529,7 @@
 		goto third
 	}
 	switch nestedErr {
-	case errClosing:
+	case poll.ErrNetClosing:
 		return nil
 	}
 	return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
@@ -547,23 +559,23 @@
 
 	for i := 0; i < 3; i++ {
 		err = c.(*TCPConn).CloseRead()
-		if perr := parseCloseError(err); perr != nil {
+		if perr := parseCloseError(err, true); perr != nil {
 			t.Errorf("#%d: %v", i, perr)
 		}
 	}
 	for i := 0; i < 3; i++ {
 		err = c.(*TCPConn).CloseWrite()
-		if perr := parseCloseError(err); perr != nil {
+		if perr := parseCloseError(err, true); perr != nil {
 			t.Errorf("#%d: %v", i, perr)
 		}
 	}
 	for i := 0; i < 3; i++ {
 		err = c.Close()
-		if perr := parseCloseError(err); perr != nil {
+		if perr := parseCloseError(err, false); perr != nil {
 			t.Errorf("#%d: %v", i, perr)
 		}
 		err = ln.Close()
-		if perr := parseCloseError(err); perr != nil {
+		if perr := parseCloseError(err, false); perr != nil {
 			t.Errorf("#%d: %v", i, perr)
 		}
 	}
@@ -576,7 +588,7 @@
 
 	for i := 0; i < 3; i++ {
 		err = pc.Close()
-		if perr := parseCloseError(err); perr != nil {
+		if perr := parseCloseError(err, false); perr != nil {
 			t.Errorf("#%d: %v", i, perr)
 		}
 	}
@@ -613,7 +625,7 @@
 		goto third
 	}
 	switch nestedErr {
-	case errClosing, errTimeout:
+	case poll.ErrNetClosing, poll.ErrTimeout:
 		return nil
 	}
 	return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
@@ -692,7 +704,7 @@
 		goto third
 	}
 	switch nestedErr {
-	case errClosing:
+	case poll.ErrNetClosing:
 		return nil
 	}
 	return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
diff --git a/libgo/go/net/external_test.go b/libgo/go/net/external_test.go
index e18b547..38788ef 100644
--- a/libgo/go/net/external_test.go
+++ b/libgo/go/net/external_test.go
@@ -15,7 +15,7 @@
 func TestResolveGoogle(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 
-	if !supportsIPv4 || !supportsIPv6 || !*testIPv4 || !*testIPv6 {
+	if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -62,7 +62,7 @@
 func TestDialGoogle(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 
-	if !supportsIPv4 || !supportsIPv6 || !*testIPv4 || !*testIPv6 {
+	if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
diff --git a/libgo/go/net/fd_plan9.go b/libgo/go/net/fd_plan9.go
index 300d8c4..46ee5d9 100644
--- a/libgo/go/net/fd_plan9.go
+++ b/libgo/go/net/fd_plan9.go
@@ -5,23 +5,15 @@
 package net
 
 import (
+	"internal/poll"
 	"io"
 	"os"
-	"sync/atomic"
 	"syscall"
-	"time"
 )
 
-type atomicBool int32
-
-func (b *atomicBool) isSet() bool { return atomic.LoadInt32((*int32)(b)) != 0 }
-func (b *atomicBool) setFalse()   { atomic.StoreInt32((*int32)(b), 0) }
-func (b *atomicBool) setTrue()    { atomic.StoreInt32((*int32)(b), 1) }
-
 // Network file descriptor.
 type netFD struct {
-	// locking/lifetime of sysfd + serialize access to Read and Write methods
-	fdmu fdMutex
+	pfd poll.FD
 
 	// immutable until Close
 	net               string
@@ -30,26 +22,12 @@
 	listen, ctl, data *os.File
 	laddr, raddr      Addr
 	isStream          bool
-
-	// deadlines
-	raio      *asyncIO
-	waio      *asyncIO
-	rtimer    *time.Timer
-	wtimer    *time.Timer
-	rtimedout atomicBool // set true when read deadline has been reached
-	wtimedout atomicBool // set true when write deadline has been reached
 }
 
-var (
-	netdir string // default network
-)
-
-func sysInit() {
-	netdir = "/net"
-}
+var netdir = "/net" // default network
 
 func newFD(net, name string, listen, ctl, data *os.File, laddr, raddr Addr) (*netFD, error) {
-	return &netFD{
+	ret := &netFD{
 		net:    net,
 		n:      name,
 		dir:    netdir + "/" + net + "/" + name,
@@ -57,7 +35,9 @@
 		ctl:    ctl, data: data,
 		laddr: laddr,
 		raddr: raddr,
-	}, nil
+	}
+	ret.pfd.Destroy = ret.destroy
+	return ret, nil
 }
 
 func (fd *netFD) init() error {
@@ -99,28 +79,10 @@
 }
 
 func (fd *netFD) Read(b []byte) (n int, err error) {
-	if fd.rtimedout.isSet() {
-		return 0, errTimeout
-	}
 	if !fd.ok() || fd.data == nil {
 		return 0, syscall.EINVAL
 	}
-	if err := fd.readLock(); err != nil {
-		return 0, err
-	}
-	defer fd.readUnlock()
-	if len(b) == 0 {
-		return 0, nil
-	}
-	fd.raio = newAsyncIO(fd.data.Read, b)
-	n, err = fd.raio.Wait()
-	fd.raio = nil
-	if isHangup(err) {
-		err = io.EOF
-	}
-	if isInterrupted(err) {
-		err = errTimeout
-	}
+	n, err = fd.pfd.Read(fd.data.Read, b)
 	if fd.net == "udp" && err == io.EOF {
 		n = 0
 		err = nil
@@ -129,23 +91,10 @@
 }
 
 func (fd *netFD) Write(b []byte) (n int, err error) {
-	if fd.wtimedout.isSet() {
-		return 0, errTimeout
-	}
 	if !fd.ok() || fd.data == nil {
 		return 0, syscall.EINVAL
 	}
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	fd.waio = newAsyncIO(fd.data.Write, b)
-	n, err = fd.waio.Wait()
-	fd.waio = nil
-	if isInterrupted(err) {
-		err = errTimeout
-	}
-	return
+	return fd.pfd.Write(fd.data.Write, b)
 }
 
 func (fd *netFD) closeRead() error {
@@ -163,8 +112,8 @@
 }
 
 func (fd *netFD) Close() error {
-	if !fd.fdmu.increfAndClose() {
-		return errClosing
+	if err := fd.pfd.Close(); err != nil {
+		return err
 	}
 	if !fd.ok() {
 		return syscall.EINVAL
@@ -216,77 +165,6 @@
 	return os.NewFile(uintptr(dfd), s), nil
 }
 
-func (fd *netFD) setDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r'+'w')
-}
-
-func (fd *netFD) setReadDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r')
-}
-
-func (fd *netFD) setWriteDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'w')
-}
-
-func setDeadlineImpl(fd *netFD, t time.Time, mode int) error {
-	d := t.Sub(time.Now())
-	if mode == 'r' || mode == 'r'+'w' {
-		fd.rtimedout.setFalse()
-	}
-	if mode == 'w' || mode == 'r'+'w' {
-		fd.wtimedout.setFalse()
-	}
-	if t.IsZero() || d < 0 {
-		// Stop timer
-		if mode == 'r' || mode == 'r'+'w' {
-			if fd.rtimer != nil {
-				fd.rtimer.Stop()
-			}
-			fd.rtimer = nil
-		}
-		if mode == 'w' || mode == 'r'+'w' {
-			if fd.wtimer != nil {
-				fd.wtimer.Stop()
-			}
-			fd.wtimer = nil
-		}
-	} else {
-		// Interrupt I/O operation once timer has expired
-		if mode == 'r' || mode == 'r'+'w' {
-			fd.rtimer = time.AfterFunc(d, func() {
-				fd.rtimedout.setTrue()
-				if fd.raio != nil {
-					fd.raio.Cancel()
-				}
-			})
-		}
-		if mode == 'w' || mode == 'r'+'w' {
-			fd.wtimer = time.AfterFunc(d, func() {
-				fd.wtimedout.setTrue()
-				if fd.waio != nil {
-					fd.waio.Cancel()
-				}
-			})
-		}
-	}
-	if !t.IsZero() && d < 0 {
-		// Interrupt current I/O operation
-		if mode == 'r' || mode == 'r'+'w' {
-			fd.rtimedout.setTrue()
-			if fd.raio != nil {
-				fd.raio.Cancel()
-			}
-		}
-		if mode == 'w' || mode == 'r'+'w' {
-			fd.wtimedout.setTrue()
-			if fd.waio != nil {
-				fd.waio.Cancel()
-			}
-		}
-	}
-	return nil
-}
-
 func setReadBuffer(fd *netFD, bytes int) error {
 	return syscall.EPLAN9
 }
@@ -294,11 +172,3 @@
 func setWriteBuffer(fd *netFD, bytes int) error {
 	return syscall.EPLAN9
 }
-
-func isHangup(err error) bool {
-	return err != nil && stringsHasSuffix(err.Error(), "Hangup")
-}
-
-func isInterrupted(err error) bool {
-	return err != nil && stringsHasSuffix(err.Error(), "interrupted")
-}
diff --git a/libgo/go/net/fd_poll_nacl.go b/libgo/go/net/fd_poll_nacl.go
deleted file mode 100644
index 8398760..0000000
--- a/libgo/go/net/fd_poll_nacl.go
+++ /dev/null
@@ -1,89 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-	"runtime"
-	"syscall"
-	"time"
-)
-
-type pollDesc struct {
-	fd      *netFD
-	closing bool
-}
-
-func (pd *pollDesc) init(fd *netFD) error { pd.fd = fd; return nil }
-
-func (pd *pollDesc) close() {}
-
-func (pd *pollDesc) evict() {
-	pd.closing = true
-	if pd.fd != nil {
-		syscall.StopIO(pd.fd.sysfd)
-		runtime.KeepAlive(pd.fd)
-	}
-}
-
-func (pd *pollDesc) prepare(mode int) error {
-	if pd.closing {
-		return errClosing
-	}
-	return nil
-}
-
-func (pd *pollDesc) prepareRead() error { return pd.prepare('r') }
-
-func (pd *pollDesc) prepareWrite() error { return pd.prepare('w') }
-
-func (pd *pollDesc) wait(mode int) error {
-	if pd.closing {
-		return errClosing
-	}
-	return errTimeout
-}
-
-func (pd *pollDesc) waitRead() error { return pd.wait('r') }
-
-func (pd *pollDesc) waitWrite() error { return pd.wait('w') }
-
-func (pd *pollDesc) waitCanceled(mode int) {}
-
-func (pd *pollDesc) waitCanceledRead() {}
-
-func (pd *pollDesc) waitCanceledWrite() {}
-
-func (fd *netFD) setDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r'+'w')
-}
-
-func (fd *netFD) setReadDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r')
-}
-
-func (fd *netFD) setWriteDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'w')
-}
-
-func setDeadlineImpl(fd *netFD, t time.Time, mode int) error {
-	d := t.UnixNano()
-	if t.IsZero() {
-		d = 0
-	}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	switch mode {
-	case 'r':
-		syscall.SetReadDeadline(fd.sysfd, d)
-	case 'w':
-		syscall.SetWriteDeadline(fd.sysfd, d)
-	case 'r' + 'w':
-		syscall.SetReadDeadline(fd.sysfd, d)
-		syscall.SetWriteDeadline(fd.sysfd, d)
-	}
-	fd.decref()
-	return nil
-}
diff --git a/libgo/go/net/fd_poll_runtime.go b/libgo/go/net/fd_poll_runtime.go
deleted file mode 100644
index 4ea92cb..0000000
--- a/libgo/go/net/fd_poll_runtime.go
+++ /dev/null
@@ -1,141 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build aix darwin dragonfly freebsd linux netbsd openbsd windows solaris
-
-package net
-
-import (
-	"runtime"
-	"sync"
-	"syscall"
-	"time"
-)
-
-// runtimeNano returns the current value of the runtime clock in nanoseconds.
-func runtimeNano() int64
-
-func runtime_pollServerInit()
-func runtime_pollOpen(fd uintptr) (uintptr, int)
-func runtime_pollClose(ctx uintptr)
-func runtime_pollWait(ctx uintptr, mode int) int
-func runtime_pollWaitCanceled(ctx uintptr, mode int) int
-func runtime_pollReset(ctx uintptr, mode int) int
-func runtime_pollSetDeadline(ctx uintptr, d int64, mode int)
-func runtime_pollUnblock(ctx uintptr)
-
-type pollDesc struct {
-	runtimeCtx uintptr
-}
-
-var serverInit sync.Once
-
-func (pd *pollDesc) init(fd *netFD) error {
-	serverInit.Do(runtime_pollServerInit)
-	ctx, errno := runtime_pollOpen(uintptr(fd.sysfd))
-	runtime.KeepAlive(fd)
-	if errno != 0 {
-		return syscall.Errno(errno)
-	}
-	pd.runtimeCtx = ctx
-	return nil
-}
-
-func (pd *pollDesc) close() {
-	if pd.runtimeCtx == 0 {
-		return
-	}
-	runtime_pollClose(pd.runtimeCtx)
-	pd.runtimeCtx = 0
-}
-
-// Evict evicts fd from the pending list, unblocking any I/O running on fd.
-func (pd *pollDesc) evict() {
-	if pd.runtimeCtx == 0 {
-		return
-	}
-	runtime_pollUnblock(pd.runtimeCtx)
-}
-
-func (pd *pollDesc) prepare(mode int) error {
-	res := runtime_pollReset(pd.runtimeCtx, mode)
-	return convertErr(res)
-}
-
-func (pd *pollDesc) prepareRead() error {
-	return pd.prepare('r')
-}
-
-func (pd *pollDesc) prepareWrite() error {
-	return pd.prepare('w')
-}
-
-func (pd *pollDesc) wait(mode int) error {
-	res := runtime_pollWait(pd.runtimeCtx, mode)
-	return convertErr(res)
-}
-
-func (pd *pollDesc) waitRead() error {
-	return pd.wait('r')
-}
-
-func (pd *pollDesc) waitWrite() error {
-	return pd.wait('w')
-}
-
-func (pd *pollDesc) waitCanceled(mode int) {
-	runtime_pollWaitCanceled(pd.runtimeCtx, mode)
-}
-
-func (pd *pollDesc) waitCanceledRead() {
-	pd.waitCanceled('r')
-}
-
-func (pd *pollDesc) waitCanceledWrite() {
-	pd.waitCanceled('w')
-}
-
-func convertErr(res int) error {
-	switch res {
-	case 0:
-		return nil
-	case 1:
-		return errClosing
-	case 2:
-		return errTimeout
-	}
-	println("unreachable: ", res)
-	panic("unreachable")
-}
-
-func (fd *netFD) setDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r'+'w')
-}
-
-func (fd *netFD) setReadDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r')
-}
-
-func (fd *netFD) setWriteDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'w')
-}
-
-func setDeadlineImpl(fd *netFD, t time.Time, mode int) error {
-	diff := int64(time.Until(t))
-	d := runtimeNano() + diff
-	if d <= 0 && diff > 0 {
-		// If the user has a deadline in the future, but the delay calculation
-		// overflows, then set the deadline to the maximum possible value.
-		d = 1<<63 - 1
-	}
-	if t.IsZero() {
-		d = 0
-	}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	runtime_pollSetDeadline(fd.pd.runtimeCtx, d, mode)
-	fd.decref()
-	return nil
-}
diff --git a/libgo/go/net/fd_posix.go b/libgo/go/net/fd_posix.go
deleted file mode 100644
index 7230479..0000000
--- a/libgo/go/net/fd_posix.go
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build aix darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
-
-package net
-
-import (
-	"io"
-	"syscall"
-)
-
-// eofError returns io.EOF when fd is available for reading end of
-// file.
-func (fd *netFD) eofError(n int, err error) error {
-	if n == 0 && err == nil && fd.sotype != syscall.SOCK_DGRAM && fd.sotype != syscall.SOCK_RAW {
-		return io.EOF
-	}
-	return err
-}
diff --git a/libgo/go/net/fd_posix_test.go b/libgo/go/net/fd_posix_test.go
deleted file mode 100644
index 85711ef..0000000
--- a/libgo/go/net/fd_posix_test.go
+++ /dev/null
@@ -1,57 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
-
-package net
-
-import (
-	"io"
-	"syscall"
-	"testing"
-)
-
-var eofErrorTests = []struct {
-	n        int
-	err      error
-	fd       *netFD
-	expected error
-}{
-	{100, nil, &netFD{sotype: syscall.SOCK_STREAM}, nil},
-	{100, io.EOF, &netFD{sotype: syscall.SOCK_STREAM}, io.EOF},
-	{100, errClosing, &netFD{sotype: syscall.SOCK_STREAM}, errClosing},
-	{0, nil, &netFD{sotype: syscall.SOCK_STREAM}, io.EOF},
-	{0, io.EOF, &netFD{sotype: syscall.SOCK_STREAM}, io.EOF},
-	{0, errClosing, &netFD{sotype: syscall.SOCK_STREAM}, errClosing},
-
-	{100, nil, &netFD{sotype: syscall.SOCK_DGRAM}, nil},
-	{100, io.EOF, &netFD{sotype: syscall.SOCK_DGRAM}, io.EOF},
-	{100, errClosing, &netFD{sotype: syscall.SOCK_DGRAM}, errClosing},
-	{0, nil, &netFD{sotype: syscall.SOCK_DGRAM}, nil},
-	{0, io.EOF, &netFD{sotype: syscall.SOCK_DGRAM}, io.EOF},
-	{0, errClosing, &netFD{sotype: syscall.SOCK_DGRAM}, errClosing},
-
-	{100, nil, &netFD{sotype: syscall.SOCK_SEQPACKET}, nil},
-	{100, io.EOF, &netFD{sotype: syscall.SOCK_SEQPACKET}, io.EOF},
-	{100, errClosing, &netFD{sotype: syscall.SOCK_SEQPACKET}, errClosing},
-	{0, nil, &netFD{sotype: syscall.SOCK_SEQPACKET}, io.EOF},
-	{0, io.EOF, &netFD{sotype: syscall.SOCK_SEQPACKET}, io.EOF},
-	{0, errClosing, &netFD{sotype: syscall.SOCK_SEQPACKET}, errClosing},
-
-	{100, nil, &netFD{sotype: syscall.SOCK_RAW}, nil},
-	{100, io.EOF, &netFD{sotype: syscall.SOCK_RAW}, io.EOF},
-	{100, errClosing, &netFD{sotype: syscall.SOCK_RAW}, errClosing},
-	{0, nil, &netFD{sotype: syscall.SOCK_RAW}, nil},
-	{0, io.EOF, &netFD{sotype: syscall.SOCK_RAW}, io.EOF},
-	{0, errClosing, &netFD{sotype: syscall.SOCK_RAW}, errClosing},
-}
-
-func TestEOFError(t *testing.T) {
-	for _, tt := range eofErrorTests {
-		actual := tt.fd.eofError(tt.n, tt.err)
-		if actual != tt.expected {
-			t.Errorf("eofError(%v, %v, %v): expected %v, actual %v", tt.n, tt.err, tt.fd.sotype, tt.expected, actual)
-		}
-	}
-}
diff --git a/libgo/go/net/fd_unix.go b/libgo/go/net/fd_unix.go
index b6ee059..e5afd1a 100644
--- a/libgo/go/net/fd_unix.go
+++ b/libgo/go/net/fd_unix.go
@@ -8,7 +8,7 @@
 
 import (
 	"context"
-	"io"
+	"internal/poll"
 	"os"
 	"runtime"
 	"sync/atomic"
@@ -17,38 +17,33 @@
 
 // Network file descriptor.
 type netFD struct {
-	// locking/lifetime of sysfd + serialize access to Read and Write methods
-	fdmu fdMutex
+	pfd poll.FD
 
 	// immutable until Close
-	sysfd       int
 	family      int
 	sotype      int
-	isStream    bool
 	isConnected bool
 	net         string
 	laddr       Addr
 	raddr       Addr
-
-	// writev cache.
-	iovecs *[]syscall.Iovec
-
-	// wait server
-	pd pollDesc
-}
-
-func sysInit() {
 }
 
 func newFD(sysfd, family, sotype int, net string) (*netFD, error) {
-	return &netFD{sysfd: sysfd, family: family, sotype: sotype, net: net, isStream: sotype == syscall.SOCK_STREAM}, nil
+	ret := &netFD{
+		pfd: poll.FD{
+			Sysfd:         sysfd,
+			IsStream:      sotype == syscall.SOCK_STREAM,
+			ZeroReadIsEOF: sotype != syscall.SOCK_DGRAM && sotype != syscall.SOCK_RAW,
+		},
+		family: family,
+		sotype: sotype,
+		net:    net,
+	}
+	return ret, nil
 }
 
 func (fd *netFD) init() error {
-	if err := fd.pd.init(fd); err != nil {
-		return err
-	}
-	return nil
+	return fd.pfd.Init(fd.net, true)
 }
 
 func (fd *netFD) setAddr(laddr, raddr Addr) {
@@ -68,22 +63,23 @@
 	return fd.net + ":" + ls + "->" + rs
 }
 
-func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (ret error) {
+func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (rsa syscall.Sockaddr, ret error) {
 	// Do not need to call fd.writeLock here,
 	// because fd is not yet accessible to user,
 	// so no concurrent operations are possible.
-	switch err := connectFunc(fd.sysfd, ra); err {
+	switch err := connectFunc(fd.pfd.Sysfd, ra); err {
 	case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
 	case nil, syscall.EISCONN:
 		select {
 		case <-ctx.Done():
-			return mapErr(ctx.Err())
+			return nil, mapErr(ctx.Err())
 		default:
 		}
-		if err := fd.init(); err != nil {
-			return err
+		if err := fd.pfd.Init(fd.net, true); err != nil {
+			return nil, err
 		}
-		return nil
+		runtime.KeepAlive(fd)
+		return nil, nil
 	case syscall.EINVAL:
 		// On Solaris we can see EINVAL if the socket has
 		// already been accepted and closed by the server.
@@ -91,18 +87,18 @@
 		// the socket will see EOF.  For details and a test
 		// case in C see https://golang.org/issue/6828.
 		if runtime.GOOS == "solaris" {
-			return nil
+			return nil, nil
 		}
 		fallthrough
 	default:
-		return os.NewSyscallError("connect", err)
+		return nil, os.NewSyscallError("connect", err)
 	}
-	if err := fd.init(); err != nil {
-		return err
+	if err := fd.pfd.Init(fd.net, true); err != nil {
+		return nil, err
 	}
 	if deadline, _ := ctx.Deadline(); !deadline.IsZero() {
-		fd.setWriteDeadline(deadline)
-		defer fd.setWriteDeadline(noDeadline)
+		fd.pfd.SetWriteDeadline(deadline)
+		defer fd.pfd.SetWriteDeadline(noDeadline)
 	}
 
 	// Start the "interrupter" goroutine, if this context might be canceled.
@@ -119,7 +115,7 @@
 		defer func() {
 			close(done)
 			if ctxErr := <-interruptRes; ctxErr != nil && ret == nil {
-				// The interrupter goroutine called setWriteDeadline,
+				// The interrupter goroutine called SetWriteDeadline,
 				// but the connect code below had returned from
 				// waitWrite already and did a successful connect (ret
 				// == nil). Because we've now poisoned the connection
@@ -135,7 +131,7 @@
 				// Force the runtime's poller to immediately give up
 				// waiting for writability, unblocking waitWrite
 				// below.
-				fd.setWriteDeadline(aLongTimeAgo)
+				fd.pfd.SetWriteDeadline(aLongTimeAgo)
 				testHookCanceledDial()
 				interruptRes <- ctx.Err()
 			case <-done:
@@ -153,66 +149,45 @@
 		// SO_ERROR socket option to see if the connection
 		// succeeded or failed. See issue 7474 for further
 		// details.
-		if err := fd.pd.waitWrite(); err != nil {
+		if err := fd.pfd.WaitWrite(); err != nil {
 			select {
 			case <-ctx.Done():
-				return mapErr(ctx.Err())
+				return nil, mapErr(ctx.Err())
 			default:
 			}
-			return err
+			return nil, err
 		}
-		nerr, err := getsockoptIntFunc(fd.sysfd, syscall.SOL_SOCKET, syscall.SO_ERROR)
+		nerr, err := getsockoptIntFunc(fd.pfd.Sysfd, syscall.SOL_SOCKET, syscall.SO_ERROR)
 		if err != nil {
-			return os.NewSyscallError("getsockopt", err)
+			return nil, os.NewSyscallError("getsockopt", err)
 		}
 		switch err := syscall.Errno(nerr); err {
 		case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
-		case syscall.Errno(0), syscall.EISCONN:
-			if runtime.GOOS != "darwin" {
-				return nil
-			}
-			// See golang.org/issue/14548.
-			// On Darwin, multiple connect system calls on
-			// a non-blocking socket never harm SO_ERROR.
-			switch err := connectFunc(fd.sysfd, ra); err {
-			case nil, syscall.EISCONN:
-				return nil
+		case syscall.EISCONN:
+			return nil, nil
+		case syscall.Errno(0):
+			// The runtime poller can wake us up spuriously;
+			// see issues 14548 and 19289. Check that we are
+			// really connected; if not, wait again.
+			if rsa, err := syscall.Getpeername(fd.pfd.Sysfd); err == nil {
+				return rsa, nil
 			}
 		default:
-			return os.NewSyscallError("getsockopt", err)
+			return nil, os.NewSyscallError("getsockopt", err)
 		}
+		runtime.KeepAlive(fd)
 	}
 }
 
-func (fd *netFD) destroy() {
-	// Poller may want to unregister fd in readiness notification mechanism,
-	// so this must be executed before closeFunc.
-	fd.pd.close()
-	closeFunc(fd.sysfd)
-	fd.sysfd = -1
-	runtime.SetFinalizer(fd, nil)
-}
-
 func (fd *netFD) Close() error {
-	if !fd.fdmu.increfAndClose() {
-		return errClosing
-	}
-	// Unblock any I/O.  Once it all unblocks and returns,
-	// so that it cannot be referring to fd.sysfd anymore,
-	// the final decref will close fd.sysfd. This should happen
-	// fairly quickly, since all the I/O is non-blocking, and any
-	// attempts to block in the pollDesc will return errClosing.
-	fd.pd.evict()
-	fd.decref()
-	return nil
+	runtime.SetFinalizer(fd, nil)
+	return fd.pfd.Close()
 }
 
 func (fd *netFD) shutdown(how int) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("shutdown", syscall.Shutdown(fd.sysfd, how))
+	err := fd.pfd.Shutdown(how)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("shutdown", err)
 }
 
 func (fd *netFD) closeRead() error {
@@ -224,233 +199,59 @@
 }
 
 func (fd *netFD) Read(p []byte) (n int, err error) {
-	if err := fd.readLock(); err != nil {
-		return 0, err
-	}
-	defer fd.readUnlock()
-	if len(p) == 0 {
-		// If the caller wanted a zero byte read, return immediately
-		// without trying. (But after acquiring the readLock.) Otherwise
-		// syscall.Read returns 0, nil and eofError turns that into
-		// io.EOF.
-		// TODO(bradfitz): make it wait for readability? (Issue 15735)
-		return 0, nil
-	}
-	if err := fd.pd.prepareRead(); err != nil {
-		return 0, err
-	}
-	if fd.isStream && len(p) > 1<<30 {
-		p = p[:1<<30]
-	}
-	for {
-		n, err = syscall.Read(fd.sysfd, p)
-		if err != nil {
-			n = 0
-			if err == syscall.EAGAIN {
-				if err = fd.pd.waitRead(); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		break
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("read", err)
-	}
-	return
+	n, err = fd.pfd.Read(p)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError("read", err)
 }
 
 func (fd *netFD) readFrom(p []byte) (n int, sa syscall.Sockaddr, err error) {
-	if err := fd.readLock(); err != nil {
-		return 0, nil, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(); err != nil {
-		return 0, nil, err
-	}
-	for {
-		n, sa, err = syscall.Recvfrom(fd.sysfd, p, 0)
-		if err != nil {
-			n = 0
-			if err == syscall.EAGAIN {
-				if err = fd.pd.waitRead(); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		break
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("recvfrom", err)
-	}
-	return
+	n, sa, err = fd.pfd.ReadFrom(p)
+	runtime.KeepAlive(fd)
+	return n, sa, wrapSyscallError("recvfrom", err)
 }
 
 func (fd *netFD) readMsg(p []byte, oob []byte) (n, oobn, flags int, sa syscall.Sockaddr, err error) {
-	if err := fd.readLock(); err != nil {
-		return 0, 0, 0, nil, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(); err != nil {
-		return 0, 0, 0, nil, err
-	}
-	for {
-		n, oobn, flags, sa, err = syscall.Recvmsg(fd.sysfd, p, oob, 0)
-		if err != nil {
-			// TODO(dfc) should n and oobn be set to 0
-			if err == syscall.EAGAIN {
-				if err = fd.pd.waitRead(); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		break
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("recvmsg", err)
-	}
-	return
+	n, oobn, flags, sa, err = fd.pfd.ReadMsg(p, oob)
+	runtime.KeepAlive(fd)
+	return n, oobn, flags, sa, wrapSyscallError("recvmsg", err)
 }
 
 func (fd *netFD) Write(p []byte) (nn int, err error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(); err != nil {
-		return 0, err
-	}
-	for {
-		var n int
-		max := len(p)
-		if fd.isStream && max-nn > 1<<30 {
-			max = nn + 1<<30
-		}
-		n, err = syscall.Write(fd.sysfd, p[nn:max])
-		if n > 0 {
-			nn += n
-		}
-		if nn == len(p) {
-			break
-		}
-		if err == syscall.EAGAIN {
-			if err = fd.pd.waitWrite(); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			break
-		}
-		if n == 0 {
-			err = io.ErrUnexpectedEOF
-			break
-		}
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("write", err)
-	}
-	return nn, err
+	nn, err = fd.pfd.Write(p)
+	runtime.KeepAlive(fd)
+	return nn, wrapSyscallError("write", err)
 }
 
 func (fd *netFD) writeTo(p []byte, sa syscall.Sockaddr) (n int, err error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(); err != nil {
-		return 0, err
-	}
-	for {
-		err = syscall.Sendto(fd.sysfd, p, 0, sa)
-		if err == syscall.EAGAIN {
-			if err = fd.pd.waitWrite(); err == nil {
-				continue
-			}
-		}
-		break
-	}
-	if err == nil {
-		n = len(p)
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("sendto", err)
-	}
-	return
+	n, err = fd.pfd.WriteTo(p, sa)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError("sendto", err)
 }
 
 func (fd *netFD) writeMsg(p []byte, oob []byte, sa syscall.Sockaddr) (n int, oobn int, err error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(); err != nil {
-		return 0, 0, err
-	}
-	for {
-		n, err = syscall.SendmsgN(fd.sysfd, p, oob, sa, 0)
-		if err == syscall.EAGAIN {
-			if err = fd.pd.waitWrite(); err == nil {
-				continue
-			}
-		}
-		break
-	}
-	if err == nil {
-		oobn = len(oob)
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("sendmsg", err)
-	}
-	return
+	n, oobn, err = fd.pfd.WriteMsg(p, oob, sa)
+	runtime.KeepAlive(fd)
+	return n, oobn, wrapSyscallError("sendmsg", err)
 }
 
 func (fd *netFD) accept() (netfd *netFD, err error) {
-	if err := fd.readLock(); err != nil {
-		return nil, err
-	}
-	defer fd.readUnlock()
-
-	var s int
-	var rsa syscall.Sockaddr
-	if err = fd.pd.prepareRead(); err != nil {
-		return nil, err
-	}
-	for {
-		s, rsa, err = accept(fd.sysfd)
-		if err != nil {
-			nerr, ok := err.(*os.SyscallError)
-			if !ok {
-				return nil, err
-			}
-			switch nerr.Err {
-			case syscall.EAGAIN:
-				if err = fd.pd.waitRead(); err == nil {
-					continue
-				}
-			case syscall.ECONNABORTED:
-				// This means that a socket on the
-				// listen queue was closed before we
-				// Accept()ed it; it's a silly error,
-				// so try again.
-				continue
-			}
-			return nil, err
+	d, rsa, errcall, err := fd.pfd.Accept()
+	if err != nil {
+		if errcall != "" {
+			err = wrapSyscallError(errcall, err)
 		}
-		break
+		return nil, err
 	}
 
-	if netfd, err = newFD(s, fd.family, fd.sotype, fd.net); err != nil {
-		closeFunc(s)
+	if netfd, err = newFD(d, fd.family, fd.sotype, fd.net); err != nil {
+		poll.CloseFunc(d)
 		return nil, err
 	}
 	if err = netfd.init(); err != nil {
 		fd.Close()
 		return nil, err
 	}
-	lsa, _ := syscall.Getsockname(netfd.sysfd)
+	lsa, _ := syscall.Getsockname(netfd.pfd.Sysfd)
 	netfd.setAddr(netfd.addrFunc()(lsa), netfd.addrFunc()(rsa))
 	return netfd, nil
 }
@@ -511,7 +312,7 @@
 }
 
 func (fd *netFD) dup() (f *os.File, err error) {
-	ns, err := dupCloseOnExec(fd.sysfd)
+	ns, err := dupCloseOnExec(fd.pfd.Sysfd)
 	if err != nil {
 		return nil, err
 	}
diff --git a/libgo/go/net/fd_windows.go b/libgo/go/net/fd_windows.go
index a976f2a..c2156b2 100644
--- a/libgo/go/net/fd_windows.go
+++ b/libgo/go/net/fd_windows.go
@@ -6,64 +6,13 @@
 
 import (
 	"context"
-	"internal/race"
+	"internal/poll"
 	"os"
 	"runtime"
-	"sync"
 	"syscall"
 	"unsafe"
 )
 
-var (
-	initErr error
-	ioSync  uint64
-)
-
-// CancelIo Windows API cancels all outstanding IO for a particular
-// socket on current thread. To overcome that limitation, we run
-// special goroutine, locked to OS single thread, that both starts
-// and cancels IO. It means, there are 2 unavoidable thread switches
-// for every IO.
-// Some newer versions of Windows has new CancelIoEx API, that does
-// not have that limitation and can be used from any thread. This
-// package uses CancelIoEx API, if present, otherwise it fallback
-// to CancelIo.
-
-var (
-	canCancelIO                               bool // determines if CancelIoEx API is present
-	skipSyncNotif                             bool
-	hasLoadSetFileCompletionNotificationModes bool
-)
-
-func sysInit() {
-	var d syscall.WSAData
-	e := syscall.WSAStartup(uint32(0x202), &d)
-	if e != nil {
-		initErr = os.NewSyscallError("wsastartup", e)
-	}
-	canCancelIO = syscall.LoadCancelIoEx() == nil
-	hasLoadSetFileCompletionNotificationModes = syscall.LoadSetFileCompletionNotificationModes() == nil
-	if hasLoadSetFileCompletionNotificationModes {
-		// It's not safe to use FILE_SKIP_COMPLETION_PORT_ON_SUCCESS if non IFS providers are installed:
-		// http://support.microsoft.com/kb/2568167
-		skipSyncNotif = true
-		protos := [2]int32{syscall.IPPROTO_TCP, 0}
-		var buf [32]syscall.WSAProtocolInfo
-		len := uint32(unsafe.Sizeof(buf))
-		n, err := syscall.WSAEnumProtocols(&protos[0], &buf[0], &len)
-		if err != nil {
-			skipSyncNotif = false
-		} else {
-			for i := int32(0); i < n; i++ {
-				if buf[i].ServiceFlags1&syscall.XP1_IFS_HANDLES == 0 {
-					skipSyncNotif = false
-					break
-				}
-			}
-		}
-	}
-}
-
 // canUseConnectEx reports whether we can use the ConnectEx Windows API call
 // for the given network type.
 func canUseConnectEx(net string) bool {
@@ -75,257 +24,39 @@
 	return false
 }
 
-// operation contains superset of data necessary to perform all async IO.
-type operation struct {
-	// Used by IOCP interface, it must be first field
-	// of the struct, as our code rely on it.
-	o syscall.Overlapped
-
-	// fields used by runtime.netpoll
-	runtimeCtx uintptr
-	mode       int32
-	errno      int32
-	qty        uint32
-
-	// fields used only by net package
-	fd     *netFD
-	errc   chan error
-	buf    syscall.WSABuf
-	sa     syscall.Sockaddr
-	rsa    *syscall.RawSockaddrAny
-	rsan   int32
-	handle syscall.Handle
-	flags  uint32
-	bufs   []syscall.WSABuf
-}
-
-func (o *operation) InitBuf(buf []byte) {
-	o.buf.Len = uint32(len(buf))
-	o.buf.Buf = nil
-	if len(buf) != 0 {
-		o.buf.Buf = &buf[0]
-	}
-}
-
-func (o *operation) InitBufs(buf *Buffers) {
-	if o.bufs == nil {
-		o.bufs = make([]syscall.WSABuf, 0, len(*buf))
-	} else {
-		o.bufs = o.bufs[:0]
-	}
-	for _, b := range *buf {
-		var p *byte
-		if len(b) > 0 {
-			p = &b[0]
-		}
-		o.bufs = append(o.bufs, syscall.WSABuf{Len: uint32(len(b)), Buf: p})
-	}
-}
-
-// ClearBufs clears all pointers to Buffers parameter captured
-// by InitBufs, so it can be released by garbage collector.
-func (o *operation) ClearBufs() {
-	for i := range o.bufs {
-		o.bufs[i].Buf = nil
-	}
-	o.bufs = o.bufs[:0]
-}
-
-// ioSrv executes net IO requests.
-type ioSrv struct {
-	req chan ioSrvReq
-}
-
-type ioSrvReq struct {
-	o      *operation
-	submit func(o *operation) error // if nil, cancel the operation
-}
-
-// ProcessRemoteIO will execute submit IO requests on behalf
-// of other goroutines, all on a single os thread, so it can
-// cancel them later. Results of all operations will be sent
-// back to their requesters via channel supplied in request.
-// It is used only when the CancelIoEx API is unavailable.
-func (s *ioSrv) ProcessRemoteIO() {
-	runtime.LockOSThread()
-	defer runtime.UnlockOSThread()
-	for r := range s.req {
-		if r.submit != nil {
-			r.o.errc <- r.submit(r.o)
-		} else {
-			r.o.errc <- syscall.CancelIo(r.o.fd.sysfd)
-		}
-	}
-}
-
-// ExecIO executes a single IO operation o. It submits and cancels
-// IO in the current thread for systems where Windows CancelIoEx API
-// is available. Alternatively, it passes the request onto
-// runtime netpoll and waits for completion or cancels request.
-func (s *ioSrv) ExecIO(o *operation, name string, submit func(o *operation) error) (int, error) {
-	fd := o.fd
-	// Notify runtime netpoll about starting IO.
-	err := fd.pd.prepare(int(o.mode))
-	if err != nil {
-		return 0, err
-	}
-	// Start IO.
-	if canCancelIO {
-		err = submit(o)
-	} else {
-		// Send request to a special dedicated thread,
-		// so it can stop the IO with CancelIO later.
-		s.req <- ioSrvReq{o, submit}
-		err = <-o.errc
-	}
-	switch err {
-	case nil:
-		// IO completed immediately
-		if o.fd.skipSyncNotif {
-			// No completion message will follow, so return immediately.
-			return int(o.qty), nil
-		}
-		// Need to get our completion message anyway.
-	case syscall.ERROR_IO_PENDING:
-		// IO started, and we have to wait for its completion.
-		err = nil
-	default:
-		return 0, err
-	}
-	// Wait for our request to complete.
-	err = fd.pd.wait(int(o.mode))
-	if err == nil {
-		// All is good. Extract our IO results and return.
-		if o.errno != 0 {
-			err = syscall.Errno(o.errno)
-			return 0, err
-		}
-		return int(o.qty), nil
-	}
-	// IO is interrupted by "close" or "timeout"
-	netpollErr := err
-	switch netpollErr {
-	case errClosing, errTimeout:
-		// will deal with those.
-	default:
-		panic("net: unexpected runtime.netpoll error: " + netpollErr.Error())
-	}
-	// Cancel our request.
-	if canCancelIO {
-		err := syscall.CancelIoEx(fd.sysfd, &o.o)
-		// Assuming ERROR_NOT_FOUND is returned, if IO is completed.
-		if err != nil && err != syscall.ERROR_NOT_FOUND {
-			// TODO(brainman): maybe do something else, but panic.
-			panic(err)
-		}
-	} else {
-		s.req <- ioSrvReq{o, nil}
-		<-o.errc
-	}
-	// Wait for cancelation to complete.
-	fd.pd.waitCanceled(int(o.mode))
-	if o.errno != 0 {
-		err = syscall.Errno(o.errno)
-		if err == syscall.ERROR_OPERATION_ABORTED { // IO Canceled
-			err = netpollErr
-		}
-		return 0, err
-	}
-	// We issued a cancelation request. But, it seems, IO operation succeeded
-	// before the cancelation request run. We need to treat the IO operation as
-	// succeeded (the bytes are actually sent/recv from network).
-	return int(o.qty), nil
-}
-
-// Start helper goroutines.
-var rsrv, wsrv *ioSrv
-var onceStartServer sync.Once
-
-func startServer() {
-	rsrv = new(ioSrv)
-	wsrv = new(ioSrv)
-	if !canCancelIO {
-		// Only CancelIo API is available. Lets start two special goroutines
-		// locked to an OS thread, that both starts and cancels IO. One will
-		// process read requests, while other will do writes.
-		rsrv.req = make(chan ioSrvReq)
-		go rsrv.ProcessRemoteIO()
-		wsrv.req = make(chan ioSrvReq)
-		go wsrv.ProcessRemoteIO()
-	}
-}
-
 // Network file descriptor.
 type netFD struct {
-	// locking/lifetime of sysfd + serialize access to Read and Write methods
-	fdmu fdMutex
+	pfd poll.FD
 
 	// immutable until Close
-	sysfd         syscall.Handle
-	family        int
-	sotype        int
-	isStream      bool
-	isConnected   bool
-	skipSyncNotif bool
-	net           string
-	laddr         Addr
-	raddr         Addr
-
-	rop operation // read operation
-	wop operation // write operation
-
-	// wait server
-	pd pollDesc
+	family      int
+	sotype      int
+	isConnected bool
+	net         string
+	laddr       Addr
+	raddr       Addr
 }
 
 func newFD(sysfd syscall.Handle, family, sotype int, net string) (*netFD, error) {
-	if initErr != nil {
-		return nil, initErr
+	ret := &netFD{
+		pfd: poll.FD{
+			Sysfd:         sysfd,
+			IsStream:      sotype == syscall.SOCK_STREAM,
+			ZeroReadIsEOF: sotype != syscall.SOCK_DGRAM && sotype != syscall.SOCK_RAW,
+		},
+		family: family,
+		sotype: sotype,
+		net:    net,
 	}
-	onceStartServer.Do(startServer)
-	return &netFD{sysfd: sysfd, family: family, sotype: sotype, net: net, isStream: sotype == syscall.SOCK_STREAM}, nil
+	return ret, nil
 }
 
 func (fd *netFD) init() error {
-	if err := fd.pd.init(fd); err != nil {
-		return err
+	errcall, err := fd.pfd.Init(fd.net)
+	if errcall != "" {
+		err = wrapSyscallError(errcall, err)
 	}
-	if hasLoadSetFileCompletionNotificationModes {
-		// We do not use events, so we can skip them always.
-		flags := uint8(syscall.FILE_SKIP_SET_EVENT_ON_HANDLE)
-		// It's not safe to skip completion notifications for UDP:
-		// http://blogs.technet.com/b/winserverperformance/archive/2008/06/26/designing-applications-for-high-performance-part-iii.aspx
-		if skipSyncNotif && fd.net == "tcp" {
-			flags |= syscall.FILE_SKIP_COMPLETION_PORT_ON_SUCCESS
-		}
-		err := syscall.SetFileCompletionNotificationModes(fd.sysfd, flags)
-		if err == nil && flags&syscall.FILE_SKIP_COMPLETION_PORT_ON_SUCCESS != 0 {
-			fd.skipSyncNotif = true
-		}
-	}
-	// Disable SIO_UDP_CONNRESET behavior.
-	// http://support.microsoft.com/kb/263823
-	switch fd.net {
-	case "udp", "udp4", "udp6":
-		ret := uint32(0)
-		flag := uint32(0)
-		size := uint32(unsafe.Sizeof(flag))
-		err := syscall.WSAIoctl(fd.sysfd, syscall.SIO_UDP_CONNRESET, (*byte)(unsafe.Pointer(&flag)), size, nil, 0, &ret, nil, 0)
-		if err != nil {
-			return os.NewSyscallError("wsaioctl", err)
-		}
-	}
-	fd.rop.mode = 'r'
-	fd.wop.mode = 'w'
-	fd.rop.fd = fd
-	fd.wop.fd = fd
-	fd.rop.runtimeCtx = fd.pd.runtimeCtx
-	fd.wop.runtimeCtx = fd.pd.runtimeCtx
-	if !canCancelIO {
-		fd.rop.errc = make(chan error)
-		fd.wop.errc = make(chan error)
-	}
-	return nil
+	return err
 }
 
 func (fd *netFD) setAddr(laddr, raddr Addr) {
@@ -334,20 +65,21 @@
 	runtime.SetFinalizer(fd, (*netFD).Close)
 }
 
-func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) error {
+// Always returns nil for connected peer address result.
+func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (syscall.Sockaddr, error) {
 	// Do not need to call fd.writeLock here,
 	// because fd is not yet accessible to user,
 	// so no concurrent operations are possible.
 	if err := fd.init(); err != nil {
-		return err
+		return nil, err
 	}
 	if deadline, ok := ctx.Deadline(); ok && !deadline.IsZero() {
-		fd.setWriteDeadline(deadline)
-		defer fd.setWriteDeadline(noDeadline)
+		fd.pfd.SetWriteDeadline(deadline)
+		defer fd.pfd.SetWriteDeadline(noDeadline)
 	}
 	if !canUseConnectEx(fd.net) {
-		err := connectFunc(fd.sysfd, ra)
-		return os.NewSyscallError("connect", err)
+		err := connectFunc(fd.pfd.Sysfd, ra)
+		return nil, os.NewSyscallError("connect", err)
 	}
 	// ConnectEx windows API requires an unconnected, previously bound socket.
 	if la == nil {
@@ -359,13 +91,10 @@
 		default:
 			panic("unexpected type in connect")
 		}
-		if err := syscall.Bind(fd.sysfd, la); err != nil {
-			return os.NewSyscallError("bind", err)
+		if err := syscall.Bind(fd.pfd.Sysfd, la); err != nil {
+			return nil, os.NewSyscallError("bind", err)
 		}
 	}
-	// Call ConnectEx API.
-	o := &fd.wop
-	o.sa = ra
 
 	// Wait for the goroutine converting context.Done into a write timeout
 	// to exist, otherwise our caller might cancel the context and
@@ -377,59 +106,37 @@
 		case <-ctx.Done():
 			// Force the runtime's poller to immediately give
 			// up waiting for writability.
-			fd.setWriteDeadline(aLongTimeAgo)
+			fd.pfd.SetWriteDeadline(aLongTimeAgo)
 			<-done
 		case <-done:
 		}
 	}()
 
-	_, err := wsrv.ExecIO(o, "ConnectEx", func(o *operation) error {
-		return connectExFunc(o.fd.sysfd, o.sa, nil, 0, nil, &o.o)
-	})
-	if err != nil {
+	// Call ConnectEx API.
+	if err := fd.pfd.ConnectEx(ra); err != nil {
 		select {
 		case <-ctx.Done():
-			return mapErr(ctx.Err())
+			return nil, mapErr(ctx.Err())
 		default:
 			if _, ok := err.(syscall.Errno); ok {
 				err = os.NewSyscallError("connectex", err)
 			}
-			return err
+			return nil, err
 		}
 	}
 	// Refresh socket properties.
-	return os.NewSyscallError("setsockopt", syscall.Setsockopt(fd.sysfd, syscall.SOL_SOCKET, syscall.SO_UPDATE_CONNECT_CONTEXT, (*byte)(unsafe.Pointer(&fd.sysfd)), int32(unsafe.Sizeof(fd.sysfd))))
-}
-
-func (fd *netFD) destroy() {
-	if fd.sysfd == syscall.InvalidHandle {
-		return
-	}
-	// Poller may want to unregister fd in readiness notification mechanism,
-	// so this must be executed before closeFunc.
-	fd.pd.close()
-	closeFunc(fd.sysfd)
-	fd.sysfd = syscall.InvalidHandle
-	// no need for a finalizer anymore
-	runtime.SetFinalizer(fd, nil)
+	return nil, os.NewSyscallError("setsockopt", syscall.Setsockopt(fd.pfd.Sysfd, syscall.SOL_SOCKET, syscall.SO_UPDATE_CONNECT_CONTEXT, (*byte)(unsafe.Pointer(&fd.pfd.Sysfd)), int32(unsafe.Sizeof(fd.pfd.Sysfd))))
 }
 
 func (fd *netFD) Close() error {
-	if !fd.fdmu.increfAndClose() {
-		return errClosing
-	}
-	// unblock pending reader and writer
-	fd.pd.evict()
-	fd.decref()
-	return nil
+	runtime.SetFinalizer(fd, nil)
+	return fd.pfd.Close()
 }
 
 func (fd *netFD) shutdown(how int) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.Shutdown(fd.sysfd, how)
+	err := fd.pfd.Shutdown(how)
+	runtime.KeepAlive(fd)
+	return err
 }
 
 func (fd *netFD) closeRead() error {
@@ -441,72 +148,21 @@
 }
 
 func (fd *netFD) Read(buf []byte) (int, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, err
-	}
-	defer fd.readUnlock()
-	o := &fd.rop
-	o.InitBuf(buf)
-	n, err := rsrv.ExecIO(o, "WSARecv", func(o *operation) error {
-		return syscall.WSARecv(o.fd.sysfd, &o.buf, 1, &o.qty, &o.flags, &o.o, nil)
-	})
-	if race.Enabled {
-		race.Acquire(unsafe.Pointer(&ioSync))
-	}
-	if len(buf) != 0 {
-		err = fd.eofError(n, err)
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("wsarecv", err)
-	}
-	return n, err
+	n, err := fd.pfd.Read(buf)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError("wsarecv", err)
 }
 
 func (fd *netFD) readFrom(buf []byte) (int, syscall.Sockaddr, error) {
-	if len(buf) == 0 {
-		return 0, nil, nil
-	}
-	if err := fd.readLock(); err != nil {
-		return 0, nil, err
-	}
-	defer fd.readUnlock()
-	o := &fd.rop
-	o.InitBuf(buf)
-	n, err := rsrv.ExecIO(o, "WSARecvFrom", func(o *operation) error {
-		if o.rsa == nil {
-			o.rsa = new(syscall.RawSockaddrAny)
-		}
-		o.rsan = int32(unsafe.Sizeof(*o.rsa))
-		return syscall.WSARecvFrom(o.fd.sysfd, &o.buf, 1, &o.qty, &o.flags, o.rsa, &o.rsan, &o.o, nil)
-	})
-	err = fd.eofError(n, err)
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("wsarecvfrom", err)
-	}
-	if err != nil {
-		return n, nil, err
-	}
-	sa, _ := o.rsa.Sockaddr()
-	return n, sa, nil
+	n, sa, err := fd.pfd.ReadFrom(buf)
+	runtime.KeepAlive(fd)
+	return n, sa, wrapSyscallError("wsarecvfrom", err)
 }
 
 func (fd *netFD) Write(buf []byte) (int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if race.Enabled {
-		race.ReleaseMerge(unsafe.Pointer(&ioSync))
-	}
-	o := &fd.wop
-	o.InitBuf(buf)
-	n, err := wsrv.ExecIO(o, "WSASend", func(o *operation) error {
-		return syscall.WSASend(o.fd.sysfd, &o.buf, 1, &o.qty, 0, &o.o, nil)
-	})
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("wsasend", err)
-	}
-	return n, err
+	n, err := fd.pfd.Write(buf)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError("wsasend", err)
 }
 
 func (c *conn) writeBuffers(v *Buffers) (int64, error) {
@@ -515,67 +171,39 @@
 	}
 	n, err := c.fd.writeBuffers(v)
 	if err != nil {
-		return n, &OpError{Op: "WSASend", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+		return n, &OpError{Op: "wsasend", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
 	}
 	return n, nil
 }
 
 func (fd *netFD) writeBuffers(buf *Buffers) (int64, error) {
-	if len(*buf) == 0 {
-		return 0, nil
-	}
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if race.Enabled {
-		race.ReleaseMerge(unsafe.Pointer(&ioSync))
-	}
-	o := &fd.wop
-	o.InitBufs(buf)
-	n, err := wsrv.ExecIO(o, "WSASend", func(o *operation) error {
-		return syscall.WSASend(o.fd.sysfd, &o.bufs[0], uint32(len(*buf)), &o.qty, 0, &o.o, nil)
-	})
-	o.ClearBufs()
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("wsasend", err)
-	}
-	testHookDidWritev(n)
-	buf.consume(int64(n))
-	return int64(n), err
+	n, err := fd.pfd.Writev((*[][]byte)(buf))
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError("wsasend", err)
 }
 
 func (fd *netFD) writeTo(buf []byte, sa syscall.Sockaddr) (int, error) {
-	if len(buf) == 0 {
-		return 0, nil
-	}
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	o := &fd.wop
-	o.InitBuf(buf)
-	o.sa = sa
-	n, err := wsrv.ExecIO(o, "WSASendto", func(o *operation) error {
-		return syscall.WSASendto(o.fd.sysfd, &o.buf, 1, &o.qty, 0, o.sa, &o.o, nil)
-	})
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("wsasendto", err)
-	}
-	return n, err
+	n, err := fd.pfd.WriteTo(buf, sa)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError("wsasendto", err)
 }
 
-func (fd *netFD) acceptOne(rawsa []syscall.RawSockaddrAny, o *operation) (*netFD, error) {
-	// Get new socket.
-	s, err := sysSocket(fd.family, fd.sotype, 0)
+func (fd *netFD) accept() (*netFD, error) {
+	s, rawsa, rsan, errcall, err := fd.pfd.Accept(func() (syscall.Handle, error) {
+		return sysSocket(fd.family, fd.sotype, 0)
+	})
+
 	if err != nil {
+		if errcall != "" {
+			err = wrapSyscallError(errcall, err)
+		}
 		return nil, err
 	}
 
 	// Associate our new socket with IOCP.
 	netfd, err := newFD(s, fd.family, fd.sotype, fd.net)
 	if err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return nil, err
 	}
 	if err := netfd.init(); err != nil {
@@ -583,71 +211,11 @@
 		return nil, err
 	}
 
-	// Submit accept request.
-	o.handle = s
-	o.rsan = int32(unsafe.Sizeof(rawsa[0]))
-	_, err = rsrv.ExecIO(o, "AcceptEx", func(o *operation) error {
-		return acceptFunc(o.fd.sysfd, o.handle, (*byte)(unsafe.Pointer(&rawsa[0])), 0, uint32(o.rsan), uint32(o.rsan), &o.qty, &o.o)
-	})
-	if err != nil {
-		netfd.Close()
-		if _, ok := err.(syscall.Errno); ok {
-			err = os.NewSyscallError("acceptex", err)
-		}
-		return nil, err
-	}
-
-	// Inherit properties of the listening socket.
-	err = syscall.Setsockopt(s, syscall.SOL_SOCKET, syscall.SO_UPDATE_ACCEPT_CONTEXT, (*byte)(unsafe.Pointer(&fd.sysfd)), int32(unsafe.Sizeof(fd.sysfd)))
-	if err != nil {
-		netfd.Close()
-		return nil, os.NewSyscallError("setsockopt", err)
-	}
-	runtime.KeepAlive(fd)
-	return netfd, nil
-}
-
-func (fd *netFD) accept() (*netFD, error) {
-	if err := fd.readLock(); err != nil {
-		return nil, err
-	}
-	defer fd.readUnlock()
-
-	o := &fd.rop
-	var netfd *netFD
-	var err error
-	var rawsa [2]syscall.RawSockaddrAny
-	for {
-		netfd, err = fd.acceptOne(rawsa[:], o)
-		if err == nil {
-			break
-		}
-		// Sometimes we see WSAECONNRESET and ERROR_NETNAME_DELETED is
-		// returned here. These happen if connection reset is received
-		// before AcceptEx could complete. These errors relate to new
-		// connection, not to AcceptEx, so ignore broken connection and
-		// try AcceptEx again for more connections.
-		nerr, ok := err.(*os.SyscallError)
-		if !ok {
-			return nil, err
-		}
-		errno, ok := nerr.Err.(syscall.Errno)
-		if !ok {
-			return nil, err
-		}
-		switch errno {
-		case syscall.ERROR_NETNAME_DELETED, syscall.WSAECONNRESET:
-			// ignore these and try again
-		default:
-			return nil, err
-		}
-	}
-
 	// Get local and peer addr out of AcceptEx buffer.
 	var lrsa, rrsa *syscall.RawSockaddrAny
 	var llen, rlen int32
 	syscall.GetAcceptExSockaddrs((*byte)(unsafe.Pointer(&rawsa[0])),
-		0, uint32(o.rsan), uint32(o.rsan), &lrsa, &llen, &rrsa, &rlen)
+		0, rsan, rsan, &lrsa, &llen, &rrsa, &rlen)
 	lsa, _ := lrsa.Sockaddr()
 	rsa, _ := rrsa.Sockaddr()
 
diff --git a/libgo/go/net/file_test.go b/libgo/go/net/file_test.go
index 6566ce2..abf8b3a 100644
--- a/libgo/go/net/file_test.go
+++ b/libgo/go/net/file_test.go
@@ -90,7 +90,7 @@
 			f, err = c1.File()
 		}
 		if err := c1.Close(); err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, false); perr != nil {
 				t.Error(perr)
 			}
 			t.Error(err)
@@ -256,7 +256,7 @@
 			f, err = c1.File()
 		}
 		if err := c1.Close(); err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, false); perr != nil {
 				t.Error(perr)
 			}
 			t.Error(err)
diff --git a/libgo/go/net/file_unix.go b/libgo/go/net/file_unix.go
index b47a614..3655a89 100644
--- a/libgo/go/net/file_unix.go
+++ b/libgo/go/net/file_unix.go
@@ -7,6 +7,7 @@
 package net
 
 import (
+	"internal/poll"
 	"os"
 	"syscall"
 )
@@ -17,7 +18,7 @@
 		return -1, err
 	}
 	if err := syscall.SetNonblock(s, true); err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return -1, os.NewSyscallError("setnonblock", err)
 	}
 	return s, nil
@@ -31,7 +32,7 @@
 	family := syscall.AF_UNSPEC
 	sotype, err := syscall.GetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_TYPE)
 	if err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return nil, os.NewSyscallError("getsockopt", err)
 	}
 	lsa, _ := syscall.Getsockname(s)
@@ -44,12 +45,12 @@
 	case *syscall.SockaddrUnix:
 		family = syscall.AF_UNIX
 	default:
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return nil, syscall.EPROTONOSUPPORT
 	}
 	fd, err := newFD(s, family, sotype, "")
 	if err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return nil, err
 	}
 	laddr := fd.addrFunc()(lsa)
diff --git a/libgo/go/net/hook_cloexec.go b/libgo/go/net/hook_cloexec.go
deleted file mode 100644
index 870f0d7..0000000
--- a/libgo/go/net/hook_cloexec.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build freebsd linux
-
-package net
-
-import "syscall"
-
-var (
-	// Placeholders for socket system calls.
-	accept4Func func(int, int) (int, syscall.Sockaddr, error) = syscall.Accept4
-)
diff --git a/libgo/go/net/hook_unix.go b/libgo/go/net/hook_unix.go
index b2522a2..7d58d0f 100644
--- a/libgo/go/net/hook_unix.go
+++ b/libgo/go/net/hook_unix.go
@@ -13,10 +13,8 @@
 	testHookCanceledDial = func() {} // for golang.org/issue/16523
 
 	// Placeholders for socket system calls.
-	socketFunc        func(int, int, int) (int, error)         = syscall.Socket
-	closeFunc         func(int) error                          = syscall.Close
-	connectFunc       func(int, syscall.Sockaddr) error        = syscall.Connect
-	listenFunc        func(int, int) error                     = syscall.Listen
-	acceptFunc        func(int) (int, syscall.Sockaddr, error) = syscall.Accept
-	getsockoptIntFunc func(int, int, int) (int, error)         = syscall.GetsockoptInt
+	socketFunc        func(int, int, int) (int, error)  = syscall.Socket
+	connectFunc       func(int, syscall.Sockaddr) error = syscall.Connect
+	listenFunc        func(int, int) error              = syscall.Listen
+	getsockoptIntFunc func(int, int, int) (int, error)  = syscall.GetsockoptInt
 )
diff --git a/libgo/go/net/hook_windows.go b/libgo/go/net/hook_windows.go
index 63ea35a..4e64dce 100644
--- a/libgo/go/net/hook_windows.go
+++ b/libgo/go/net/hook_windows.go
@@ -13,10 +13,7 @@
 	testHookDialChannel = func() { time.Sleep(time.Millisecond) } // see golang.org/issue/5349
 
 	// Placeholders for socket system calls.
-	socketFunc    func(int, int, int) (syscall.Handle, error)                                                             = syscall.Socket
-	closeFunc     func(syscall.Handle) error                                                                              = syscall.Closesocket
-	connectFunc   func(syscall.Handle, syscall.Sockaddr) error                                                            = syscall.Connect
-	connectExFunc func(syscall.Handle, syscall.Sockaddr, *byte, uint32, *uint32, *syscall.Overlapped) error               = syscall.ConnectEx
-	listenFunc    func(syscall.Handle, int) error                                                                         = syscall.Listen
-	acceptFunc    func(syscall.Handle, syscall.Handle, *byte, uint32, uint32, uint32, *uint32, *syscall.Overlapped) error = syscall.AcceptEx
+	socketFunc  func(int, int, int) (syscall.Handle, error)  = syscall.Socket
+	connectFunc func(syscall.Handle, syscall.Sockaddr) error = syscall.Connect
+	listenFunc  func(syscall.Handle, int) error              = syscall.Listen
 )
diff --git a/libgo/go/net/http/cgi/host_test.go b/libgo/go/net/http/cgi/host_test.go
index f058372..1336300 100644
--- a/libgo/go/net/http/cgi/host_test.go
+++ b/libgo/go/net/http/cgi/host_test.go
@@ -409,7 +409,7 @@
 	}
 
 	childRunning := func() bool {
-		return isProcessRunning(t, pid)
+		return isProcessRunning(pid)
 	}
 
 	if !childRunning() {
diff --git a/libgo/go/net/http/cgi/posix_test.go b/libgo/go/net/http/cgi/posix_test.go
index 5ff9e7d..9396ce0 100644
--- a/libgo/go/net/http/cgi/posix_test.go
+++ b/libgo/go/net/http/cgi/posix_test.go
@@ -9,10 +9,9 @@
 import (
 	"os"
 	"syscall"
-	"testing"
 )
 
-func isProcessRunning(t *testing.T, pid int) bool {
+func isProcessRunning(pid int) bool {
 	p, err := os.FindProcess(pid)
 	if err != nil {
 		return false
diff --git a/libgo/go/net/http/client.go b/libgo/go/net/http/client.go
index 0005538..4c9084a 100644
--- a/libgo/go/net/http/client.go
+++ b/libgo/go/net/http/client.go
@@ -38,20 +38,20 @@
 // When following redirects, the Client will forward all headers set on the
 // initial Request except:
 //
-//	* when forwarding sensitive headers like "Authorization",
-//	  "WWW-Authenticate", and "Cookie" to untrusted targets.
-//	  These headers will be ignored when following a redirect to a domain
-//	  that is not a subdomain match or exact match of the initial domain.
-//	  For example, a redirect from "foo.com" to either "foo.com" or "sub.foo.com"
-//	  will forward the sensitive headers, but a redirect to "bar.com" will not.
+// • when forwarding sensitive headers like "Authorization",
+// "WWW-Authenticate", and "Cookie" to untrusted targets.
+// These headers will be ignored when following a redirect to a domain
+// that is not a subdomain match or exact match of the initial domain.
+// For example, a redirect from "foo.com" to either "foo.com" or "sub.foo.com"
+// will forward the sensitive headers, but a redirect to "bar.com" will not.
 //
-//	* when forwarding the "Cookie" header with a non-nil cookie Jar.
-//	  Since each redirect may mutate the state of the cookie jar,
-//	  a redirect may possibly alter a cookie set in the initial request.
-//	  When forwarding the "Cookie" header, any mutated cookies will be omitted,
-//	  with the expectation that the Jar will insert those mutated cookies
-//	  with the updated values (assuming the origin matches).
-//	  If Jar is nil, the initial cookies are forwarded without change.
+// • when forwarding the "Cookie" header with a non-nil cookie Jar.
+// Since each redirect may mutate the state of the cookie jar,
+// a redirect may possibly alter a cookie set in the initial request.
+// When forwarding the "Cookie" header, any mutated cookies will be omitted,
+// with the expectation that the Jar will insert those mutated cookies
+// with the updated values (assuming the origin matches).
+// If Jar is nil, the initial cookies are forwarded without change.
 //
 type Client struct {
 	// Transport specifies the mechanism by which individual
@@ -494,17 +494,21 @@
 	}
 
 	var (
-		deadline    = c.deadline()
-		reqs        []*Request
-		resp        *Response
-		copyHeaders = c.makeHeadersCopier(req)
+		deadline      = c.deadline()
+		reqs          []*Request
+		resp          *Response
+		copyHeaders   = c.makeHeadersCopier(req)
+		reqBodyClosed = false // have we closed the current req.Body?
 
 		// Redirect behavior:
 		redirectMethod string
 		includeBody    bool
 	)
 	uerr := func(err error) error {
-		req.closeBody()
+		// the body may have been closed already by c.send()
+		if !reqBodyClosed {
+			req.closeBody()
+		}
 		method := valueOrDefault(reqs[0].Method, "GET")
 		var urlStr string
 		if resp != nil && resp.Request != nil {
@@ -524,10 +528,12 @@
 		if len(reqs) > 0 {
 			loc := resp.Header.Get("Location")
 			if loc == "" {
+				resp.closeBody()
 				return nil, uerr(fmt.Errorf("%d response missing Location header", resp.StatusCode))
 			}
 			u, err := req.URL.Parse(loc)
 			if err != nil {
+				resp.closeBody()
 				return nil, uerr(fmt.Errorf("failed to parse Location header %q: %v", loc, err))
 			}
 			ireq := reqs[0]
@@ -542,6 +548,7 @@
 			if includeBody && ireq.GetBody != nil {
 				req.Body, err = ireq.GetBody()
 				if err != nil {
+					resp.closeBody()
 					return nil, uerr(err)
 				}
 				req.ContentLength = ireq.ContentLength
@@ -593,6 +600,8 @@
 		var err error
 		var didTimeout func() bool
 		if resp, didTimeout, err = c.send(req, deadline); err != nil {
+			// c.send() always closes req.Body
+			reqBodyClosed = true
 			if !deadline.IsZero() && didTimeout() {
 				err = &httpError{
 					err:     err.Error() + " (Client.Timeout exceeded while awaiting headers)",
diff --git a/libgo/go/net/http/client_test.go b/libgo/go/net/http/client_test.go
index 4f674dd..b9a1c31 100644
--- a/libgo/go/net/http/client_test.go
+++ b/libgo/go/net/http/client_test.go
@@ -10,7 +10,6 @@
 	"bytes"
 	"context"
 	"crypto/tls"
-	"crypto/x509"
 	"encoding/base64"
 	"errors"
 	"fmt"
@@ -73,7 +72,7 @@
 	ts := httptest.NewServer(robotsTxtHandler)
 	defer ts.Close()
 
-	c := &Client{Transport: &Transport{DisableKeepAlives: true}}
+	c := ts.Client()
 	r, err := c.Get(ts.URL)
 	var b []byte
 	if err == nil {
@@ -220,10 +219,7 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	_, err := c.Get(ts.URL)
 	if e, g := "Get /?n=10: stopped after 10 redirects", fmt.Sprintf("%v", err); e != g {
 		t.Errorf("with default client Get, expected error %q, got %q", e, g)
@@ -252,13 +248,10 @@
 	var checkErr error
 	var lastVia []*Request
 	var lastReq *Request
-	c = &Client{
-		Transport: tr,
-		CheckRedirect: func(req *Request, via []*Request) error {
-			lastReq = req
-			lastVia = via
-			return checkErr
-		},
+	c.CheckRedirect = func(req *Request, via []*Request) error {
+		lastReq = req
+		lastVia = via
+		return checkErr
 	}
 	res, err := c.Get(ts.URL)
 	if err != nil {
@@ -304,6 +297,7 @@
 	}
 }
 
+// Tests that Client redirects' contexts are derived from the original request's context.
 func TestClientRedirectContext(t *testing.T) {
 	setParallel(t)
 	defer afterTest(t)
@@ -312,19 +306,16 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-
 	ctx, cancel := context.WithCancel(context.Background())
-	c := &Client{
-		Transport: tr,
-		CheckRedirect: func(req *Request, via []*Request) error {
-			cancel()
-			if len(via) > 2 {
-				return errors.New("too many redirects")
-			}
+	c := ts.Client()
+	c.CheckRedirect = func(req *Request, via []*Request) error {
+		cancel()
+		select {
+		case <-req.Context().Done():
 			return nil
-		},
+		case <-time.After(5 * time.Second):
+			return errors.New("redirected request's context never expired after root request canceled")
+		}
 	}
 	req, _ := NewRequest("GET", ts.URL, nil)
 	req = req.WithContext(ctx)
@@ -458,11 +449,12 @@
 	}))
 	defer ts.Close()
 
+	c := ts.Client()
 	for _, tt := range table {
 		content := tt.redirectBody
 		req, _ := NewRequest(method, ts.URL+tt.suffix, strings.NewReader(content))
 		req.GetBody = func() (io.ReadCloser, error) { return ioutil.NopCloser(strings.NewReader(content)), nil }
-		res, err := DefaultClient.Do(req)
+		res, err := c.Do(req)
 
 		if err != nil {
 			t.Fatal(err)
@@ -516,17 +508,12 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-
-	c := &Client{
-		Transport: tr,
-		CheckRedirect: func(req *Request, via []*Request) error {
-			if req.Response == nil {
-				t.Error("expected non-nil Request.Response")
-			}
-			return ErrUseLastResponse
-		},
+	c := ts.Client()
+	c.CheckRedirect = func(req *Request, via []*Request) error {
+		if req.Response == nil {
+			t.Error("expected non-nil Request.Response")
+		}
+		return ErrUseLastResponse
 	}
 	res, err := c.Get(ts.URL)
 	if err != nil {
@@ -555,7 +542,8 @@
 		w.WriteHeader(308)
 	}))
 	defer ts.Close()
-	res, err := Get(ts.URL)
+	c := ts.Client()
+	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -582,8 +570,9 @@
 	if err != nil {
 		t.Fatal(err)
 	}
+	c := ts.Client()
 	req.GetBody = nil // so it can't rewind.
-	res, err := DefaultClient.Do(req)
+	res, err := c.Do(req)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -673,12 +662,8 @@
 	var ts *httptest.Server
 	ts = httptest.NewServer(echoCookiesRedirectHandler)
 	defer ts.Close()
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{
-		Transport: tr,
-		Jar:       new(TestJar),
-	}
+	c := ts.Client()
+	c.Jar = new(TestJar)
 	u, _ := url.Parse(ts.URL)
 	c.Jar.SetCookies(u, []*Cookie{expectedCookies[0]})
 	resp, err := c.Get(ts.URL)
@@ -722,13 +707,10 @@
 	}))
 	defer ts.Close()
 	jar := new(RecordingJar)
-	c := &Client{
-		Jar: jar,
-		Transport: &Transport{
-			Dial: func(_ string, _ string) (net.Conn, error) {
-				return net.Dial("tcp", ts.Listener.Addr().String())
-			},
-		},
+	c := ts.Client()
+	c.Jar = jar
+	c.Transport.(*Transport).Dial = func(_ string, _ string) (net.Conn, error) {
+		return net.Dial("tcp", ts.Listener.Addr().String())
 	}
 	_, err := c.Get("http://firsthost.fake/")
 	if err != nil {
@@ -840,7 +822,8 @@
 		}
 		return c, err
 	}
-	c := &Client{Transport: &Transport{Dial: dialer}}
+	c := ts.Client()
+	c.Transport.(*Transport).Dial = dialer
 
 	_, err := c.Get(ts.URL)
 	if err != nil {
@@ -873,14 +856,11 @@
 	// TODO(bradfitz): add tests for skipping hostname checks too?
 	// would require a new cert for testing, and probably
 	// redundant with these tests.
+	c := ts.Client()
 	for _, insecure := range []bool{true, false} {
-		tr := &Transport{
-			TLSClientConfig: &tls.Config{
-				InsecureSkipVerify: insecure,
-			},
+		c.Transport.(*Transport).TLSClientConfig = &tls.Config{
+			InsecureSkipVerify: insecure,
 		}
-		defer tr.CloseIdleConnections()
-		c := &Client{Transport: tr}
 		res, err := c.Get(ts.URL)
 		if (err == nil) != insecure {
 			t.Errorf("insecure=%v: got unexpected err=%v", insecure, err)
@@ -914,22 +894,6 @@
 	}
 }
 
-func newTLSTransport(t *testing.T, ts *httptest.Server) *Transport {
-	certs := x509.NewCertPool()
-	for _, c := range ts.TLS.Certificates {
-		roots, err := x509.ParseCertificates(c.Certificate[len(c.Certificate)-1])
-		if err != nil {
-			t.Fatalf("error parsing server's root cert: %v", err)
-		}
-		for _, root := range roots {
-			certs.AddCert(root)
-		}
-	}
-	return &Transport{
-		TLSClientConfig: &tls.Config{RootCAs: certs},
-	}
-}
-
 func TestClientWithCorrectTLSServerName(t *testing.T) {
 	defer afterTest(t)
 
@@ -941,9 +905,8 @@
 	}))
 	defer ts.Close()
 
-	trans := newTLSTransport(t, ts)
-	trans.TLSClientConfig.ServerName = serverName
-	c := &Client{Transport: trans}
+	c := ts.Client()
+	c.Transport.(*Transport).TLSClientConfig.ServerName = serverName
 	if _, err := c.Get(ts.URL); err != nil {
 		t.Fatalf("expected successful TLS connection, got error: %v", err)
 	}
@@ -956,9 +919,8 @@
 	errc := make(chanWriter, 10) // but only expecting 1
 	ts.Config.ErrorLog = log.New(errc, "", 0)
 
-	trans := newTLSTransport(t, ts)
-	trans.TLSClientConfig.ServerName = "badserver"
-	c := &Client{Transport: trans}
+	c := ts.Client()
+	c.Transport.(*Transport).TLSClientConfig.ServerName = "badserver"
 	_, err := c.Get(ts.URL)
 	if err == nil {
 		t.Fatalf("expected an error")
@@ -992,13 +954,12 @@
 	}))
 	defer ts.Close()
 
-	tr := newTLSTransport(t, ts)
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 	tr.TLSClientConfig.ServerName = "example.com" // one of httptest's Server cert names
 	tr.Dial = func(netw, addr string) (net.Conn, error) {
 		return net.Dial(netw, ts.Listener.Addr().String())
 	}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
 	res, err := c.Get("https://some-other-host.tld/")
 	if err != nil {
 		t.Fatal(err)
@@ -1013,13 +974,12 @@
 	}))
 	defer ts.Close()
 
-	tr := newTLSTransport(t, ts)
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 	tr.TLSClientConfig.CipherSuites = []uint16{tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA}
 	tr.Dial = func(netw, addr string) (net.Conn, error) {
 		return net.Dial(netw, ts.Listener.Addr().String())
 	}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
 	res, err := c.Get("https://example.com/")
 	if err != nil {
 		t.Fatal(err)
@@ -1114,14 +1074,12 @@
 		}
 	}))
 	defer ts.Close()
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
 	req, err := NewRequest("GET", ts.URL, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
 	req.URL.User = url.User(gopher)
+	c := ts.Client()
 	resp, err := c.Do(req)
 	if err != nil {
 		t.Fatal(err)
@@ -1498,21 +1456,17 @@
 	defer ts2.Close()
 	ts2URL = ts2.URL
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{
-		Transport: tr,
-		CheckRedirect: func(r *Request, via []*Request) error {
-			want := Header{
-				"User-Agent": []string{ua},
-				"X-Foo":      []string{xfoo},
-				"Referer":    []string{ts2URL},
-			}
-			if !reflect.DeepEqual(r.Header, want) {
-				t.Errorf("CheckRedirect Request.Header = %#v; want %#v", r.Header, want)
-			}
-			return nil
-		},
+	c := ts1.Client()
+	c.CheckRedirect = func(r *Request, via []*Request) error {
+		want := Header{
+			"User-Agent": []string{ua},
+			"X-Foo":      []string{xfoo},
+			"Referer":    []string{ts2URL},
+		}
+		if !reflect.DeepEqual(r.Header, want) {
+			t.Errorf("CheckRedirect Request.Header = %#v; want %#v", r.Header, want)
+		}
+		return nil
 	}
 
 	req, _ := NewRequest("GET", ts2.URL, nil)
@@ -1601,13 +1555,9 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
 	jar, _ := cookiejar.New(nil)
-	c := &Client{
-		Transport: tr,
-		Jar:       jar,
-	}
+	c := ts.Client()
+	c.Jar = jar
 
 	u, _ := url.Parse(ts.URL)
 	req, _ := NewRequest("GET", ts.URL, nil)
@@ -1725,9 +1675,7 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-
+	c := ts.Client()
 	for i, tt := range tests {
 		handlerc <- func(w ResponseWriter, r *Request) {
 			w.Header().Set("Location", ts.URL)
@@ -1740,7 +1688,6 @@
 			continue
 		}
 
-		c := &Client{Transport: tr}
 		c.CheckRedirect = func(req *Request, via []*Request) error {
 			if got, want := req.Method, tt.wantMethod; got != want {
 				return fmt.Errorf("#%d: got next method %q; want %q", i, got, want)
@@ -1780,8 +1727,8 @@
 	return nil
 }
 
-// Issue 18239: make sure the Transport doesn't retry requests with bodies.
-// (Especially if Request.GetBody is not defined.)
+// Issue 18239: make sure the Transport doesn't retry requests with bodies
+// if Request.GetBody is not defined.
 func TestTransportBodyReadError(t *testing.T) {
 	setParallel(t)
 	defer afterTest(t)
@@ -1794,9 +1741,8 @@
 		w.Header().Set("X-Body-Read", fmt.Sprintf("%v, %v", n, err))
 	}))
 	defer ts.Close()
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	// Do one initial successful request to create an idle TCP connection
 	// for the subsequent request to reuse. (The Transport only retries
@@ -1816,6 +1762,7 @@
 	if err != nil {
 		t.Fatal(err)
 	}
+	req = req.WithT(t)
 	_, err = tr.RoundTrip(req)
 	if err != someErr {
 		t.Errorf("Got error: %v; want Request.Body read error: %v", err, someErr)
diff --git a/libgo/go/net/http/clientserver_test.go b/libgo/go/net/http/clientserver_test.go
index 580115c..20feaa7 100644
--- a/libgo/go/net/http/clientserver_test.go
+++ b/libgo/go/net/http/clientserver_test.go
@@ -1385,3 +1385,30 @@
 		t.Errorf("Trailer = %#v; want %#v", res.Trailer, want)
 	}
 }
+
+func TestBadResponseAfterReadingBody(t *testing.T) {
+	defer afterTest(t)
+	cst := newClientServerTest(t, false, HandlerFunc(func(w ResponseWriter, r *Request) {
+		_, err := io.Copy(ioutil.Discard, r.Body)
+		if err != nil {
+			t.Fatal(err)
+		}
+		c, _, err := w.(Hijacker).Hijack()
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer c.Close()
+		fmt.Fprintln(c, "some bogus crap")
+	}))
+	defer cst.close()
+
+	closes := 0
+	res, err := cst.c.Post(cst.ts.URL, "text/plain", countCloseReader{&closes, strings.NewReader("hello")})
+	if err == nil {
+		res.Body.Close()
+		t.Fatal("expected an error to be returned from Post")
+	}
+	if closes != 1 {
+		t.Errorf("closes = %d; want 1", closes)
+	}
+}
diff --git a/libgo/go/net/http/cookie.go b/libgo/go/net/http/cookie.go
index 5a67476..cf52248 100644
--- a/libgo/go/net/http/cookie.go
+++ b/libgo/go/net/http/cookie.go
@@ -328,7 +328,7 @@
 	if len(v) == 0 {
 		return v
 	}
-	if v[0] == ' ' || v[0] == ',' || v[len(v)-1] == ' ' || v[len(v)-1] == ',' {
+	if strings.IndexByte(v, ' ') >= 0 || strings.IndexByte(v, ',') >= 0 {
 		return `"` + v + `"`
 	}
 	return v
diff --git a/libgo/go/net/http/cookie_test.go b/libgo/go/net/http/cookie_test.go
index b3e54f8..9d199a3 100644
--- a/libgo/go/net/http/cookie_test.go
+++ b/libgo/go/net/http/cookie_test.go
@@ -69,7 +69,7 @@
 	// are disallowed by RFC 6265 but are common in the wild.
 	{
 		&Cookie{Name: "special-1", Value: "a z"},
-		`special-1=a z`,
+		`special-1="a z"`,
 	},
 	{
 		&Cookie{Name: "special-2", Value: " z"},
@@ -85,7 +85,7 @@
 	},
 	{
 		&Cookie{Name: "special-5", Value: "a,z"},
-		`special-5=a,z`,
+		`special-5="a,z"`,
 	},
 	{
 		&Cookie{Name: "special-6", Value: ",z"},
@@ -398,9 +398,12 @@
 		{"foo\"bar", "foobar"},
 		{"\x00\x7e\x7f\x80", "\x7e"},
 		{`"withquotes"`, "withquotes"},
-		{"a z", "a z"},
+		{"a z", `"a z"`},
 		{" z", `" z"`},
 		{"a ", `"a "`},
+		{"a,z", `"a,z"`},
+		{",z", `",z"`},
+		{"a,", `"a,"`},
 	}
 	for _, tt := range tests {
 		if got := sanitizeCookieValue(tt.in); got != tt.want {
diff --git a/libgo/go/net/http/cookiejar/jar.go b/libgo/go/net/http/cookiejar/jar.go
index f89abbc..ef8c35b 100644
--- a/libgo/go/net/http/cookiejar/jar.go
+++ b/libgo/go/net/http/cookiejar/jar.go
@@ -331,7 +331,7 @@
 	var i int
 	if psl == nil {
 		i = strings.LastIndex(host, ".")
-		if i == -1 {
+		if i <= 0 {
 			return host
 		}
 	} else {
@@ -345,6 +345,9 @@
 			// Storing cookies under host is a safe stopgap.
 			return host
 		}
+		// Only len(suffix) is used to determine the jar key from
+		// here on, so it is okay if psl.PublicSuffix("www.buggy.psl")
+		// returns "com" as the jar key is generated from host.
 	}
 	prevDot := strings.LastIndex(host[:i-1], ".")
 	return host[prevDot+1:]
diff --git a/libgo/go/net/http/cookiejar/jar_test.go b/libgo/go/net/http/cookiejar/jar_test.go
index 3aa6015..47fb1ab 100644
--- a/libgo/go/net/http/cookiejar/jar_test.go
+++ b/libgo/go/net/http/cookiejar/jar_test.go
@@ -19,6 +19,9 @@
 
 // testPSL implements PublicSuffixList with just two rules: "co.uk"
 // and the default rule "*".
+// The implementation has two intentional bugs:
+//    PublicSuffix("www.buggy.psl") == "xy"
+//    PublicSuffix("www2.buggy.psl") == "com"
 type testPSL struct{}
 
 func (testPSL) String() string {
@@ -28,6 +31,12 @@
 	if d == "co.uk" || strings.HasSuffix(d, ".co.uk") {
 		return "co.uk"
 	}
+	if d == "www.buggy.psl" {
+		return "xy"
+	}
+	if d == "www2.buggy.psl" {
+		return "com"
+	}
 	return d[strings.LastIndex(d, ".")+1:]
 }
 
@@ -125,6 +134,17 @@
 	"[2001:4860:0:::68]:8080": "2001:4860:0:::68",
 	"www.bücher.de":           "www.xn--bcher-kva.de",
 	"www.example.com.":        "www.example.com",
+	// TODO: Fix canonicalHost so that all of the following malformed
+	// domain names trigger an error. (This list is not exhaustive, e.g.
+	// malformed internationalized domain names are missing.)
+	".":                       "",
+	"..":                      ".",
+	"...":                     "..",
+	".net":                    ".net",
+	".net.":                   ".net",
+	"a..":                     "a.",
+	"b.a..":                   "b.a.",
+	"weird.stuff...":          "weird.stuff..",
 	"[bad.unmatched.bracket:": "error",
 }
 
@@ -133,7 +153,7 @@
 		got, err := canonicalHost(h)
 		if want == "error" {
 			if err == nil {
-				t.Errorf("%q: got nil error, want non-nil", h)
+				t.Errorf("%q: got %q and nil error, want non-nil", h, got)
 			}
 			continue
 		}
@@ -176,6 +196,17 @@
 	"co.uk":               "co.uk",
 	"uk":                  "uk",
 	"192.168.0.5":         "192.168.0.5",
+	"www.buggy.psl":       "www.buggy.psl",
+	"www2.buggy.psl":      "buggy.psl",
+	// The following are actual outputs of canonicalHost for
+	// malformed inputs to canonicalHost (see above).
+	"":              "",
+	".":             ".",
+	"..":            ".",
+	".net":          ".net",
+	"a.":            "a.",
+	"b.a.":          "a.",
+	"weird.stuff..": ".",
 }
 
 func TestJarKey(t *testing.T) {
@@ -197,6 +228,15 @@
 	"co.uk":               "co.uk",
 	"uk":                  "uk",
 	"192.168.0.5":         "192.168.0.5",
+	// The following are actual outputs of canonicalHost for
+	// malformed inputs to canonicalHost.
+	"":              "",
+	".":             ".",
+	"..":            "..",
+	".net":          ".net",
+	"a.":            "a.",
+	"b.a.":          "a.",
+	"weird.stuff..": "stuff..",
 }
 
 func TestJarKeyNilPSL(t *testing.T) {
@@ -1265,3 +1305,18 @@
 		test.run(t, jar)
 	}
 }
+
+func TestIssue19384(t *testing.T) {
+	cookies := []*http.Cookie{{Name: "name", Value: "value"}}
+	for _, host := range []string{"", ".", "..", "..."} {
+		jar, _ := New(nil)
+		u := &url.URL{Scheme: "http", Host: host, Path: "/"}
+		if got := jar.Cookies(u); len(got) != 0 {
+			t.Errorf("host %q, got %v", host, got)
+		}
+		jar.SetCookies(u, cookies)
+		if got := jar.Cookies(u); len(got) != 1 || got[0].Value != "value" {
+			t.Errorf("host %q, got %v", host, got)
+		}
+	}
+}
diff --git a/libgo/go/net/http/export_test.go b/libgo/go/net/http/export_test.go
index b61f58b..2ef145e 100644
--- a/libgo/go/net/http/export_test.go
+++ b/libgo/go/net/http/export_test.go
@@ -8,24 +8,29 @@
 package http
 
 import (
+	"context"
 	"net"
 	"sort"
 	"sync"
+	"testing"
 	"time"
 )
 
 var (
-	DefaultUserAgent             = defaultUserAgent
-	NewLoggingConn               = newLoggingConn
-	ExportAppendTime             = appendTime
-	ExportRefererForURL          = refererForURL
-	ExportServerNewConn          = (*Server).newConn
-	ExportCloseWriteAndWait      = (*conn).closeWriteAndWait
-	ExportErrRequestCanceled     = errRequestCanceled
-	ExportErrRequestCanceledConn = errRequestCanceledConn
-	ExportServeFile              = serveFile
-	ExportScanETag               = scanETag
-	ExportHttp2ConfigureServer   = http2ConfigureServer
+	DefaultUserAgent                  = defaultUserAgent
+	NewLoggingConn                    = newLoggingConn
+	ExportAppendTime                  = appendTime
+	ExportRefererForURL               = refererForURL
+	ExportServerNewConn               = (*Server).newConn
+	ExportCloseWriteAndWait           = (*conn).closeWriteAndWait
+	ExportErrRequestCanceled          = errRequestCanceled
+	ExportErrRequestCanceledConn      = errRequestCanceledConn
+	ExportErrServerClosedIdle         = errServerClosedIdle
+	ExportServeFile                   = serveFile
+	ExportScanETag                    = scanETag
+	ExportHttp2ConfigureServer        = http2ConfigureServer
+	Export_shouldCopyHeaderOnRedirect = shouldCopyHeaderOnRedirect
+	Export_writeStatusLine            = writeStatusLine
 )
 
 func init() {
@@ -186,8 +191,6 @@
 	return nil
 }
 
-var Export_shouldCopyHeaderOnRedirect = shouldCopyHeaderOnRedirect
-
 func (s *Server) ExportAllConnsIdle() bool {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -199,3 +202,7 @@
 	}
 	return true
 }
+
+func (r *Request) WithT(t *testing.T) *Request {
+	return r.WithContext(context.WithValue(r.Context(), tLogKey{}, t.Logf))
+}
diff --git a/libgo/go/net/http/fcgi/child.go b/libgo/go/net/http/fcgi/child.go
index 8870424..30a6b2c 100644
--- a/libgo/go/net/http/fcgi/child.go
+++ b/libgo/go/net/http/fcgi/child.go
@@ -7,6 +7,7 @@
 // This file implements FastCGI from the perspective of a child process.
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -31,6 +32,10 @@
 	keepConn  bool
 }
 
+// envVarsContextKey uniquely identifies a mapping of CGI
+// environment variables to their values in a request context
+type envVarsContextKey struct{}
+
 func newRequest(reqId uint16, flags uint8) *request {
 	r := &request{
 		reqId:    reqId,
@@ -259,6 +264,18 @@
 	}
 }
 
+// filterOutUsedEnvVars returns a new map of env vars without the
+// variables in the given envVars map that are read for creating each http.Request
+func filterOutUsedEnvVars(envVars map[string]string) map[string]string {
+	withoutUsedEnvVars := make(map[string]string)
+	for k, v := range envVars {
+		if addFastCGIEnvToContext(k) {
+			withoutUsedEnvVars[k] = v
+		}
+	}
+	return withoutUsedEnvVars
+}
+
 func (c *child) serveRequest(req *request, body io.ReadCloser) {
 	r := newResponse(c, req)
 	httpReq, err := cgi.RequestFromMap(req.params)
@@ -268,6 +285,9 @@
 		c.conn.writeRecord(typeStderr, req.reqId, []byte(err.Error()))
 	} else {
 		httpReq.Body = body
+		withoutUsedEnvVars := filterOutUsedEnvVars(req.params)
+		envVarCtx := context.WithValue(httpReq.Context(), envVarsContextKey{}, withoutUsedEnvVars)
+		httpReq = httpReq.WithContext(envVarCtx)
 		c.handler.ServeHTTP(r, httpReq)
 	}
 	r.Close()
@@ -329,3 +349,39 @@
 		go c.serve()
 	}
 }
+
+// ProcessEnv returns FastCGI environment variables associated with the request r
+// for which no effort was made to be included in the request itself - the data
+// is hidden in the request's context. As an example, if REMOTE_USER is set for a
+// request, it will not be found anywhere in r, but it will be included in
+// ProcessEnv's response (via r's context).
+func ProcessEnv(r *http.Request) map[string]string {
+	env, _ := r.Context().Value(envVarsContextKey{}).(map[string]string)
+	return env
+}
+
+// addFastCGIEnvToContext reports whether to include the FastCGI environment variable s
+// in the http.Request.Context, accessible via ProcessEnv.
+func addFastCGIEnvToContext(s string) bool {
+	// Exclude things supported by net/http natively:
+	switch s {
+	case "CONTENT_LENGTH", "CONTENT_TYPE", "HTTPS",
+		"PATH_INFO", "QUERY_STRING", "REMOTE_ADDR",
+		"REMOTE_HOST", "REMOTE_PORT", "REQUEST_METHOD",
+		"REQUEST_URI", "SCRIPT_NAME", "SERVER_PROTOCOL":
+		return false
+	}
+	if strings.HasPrefix(s, "HTTP_") {
+		return false
+	}
+	// Explicitly include FastCGI-specific things.
+	// This list is redundant with the default "return true" below.
+	// Consider this documentation of the sorts of things we expect
+	// to maybe see.
+	switch s {
+	case "REMOTE_USER":
+		return true
+	}
+	// Unknown, so include it to be safe.
+	return true
+}
diff --git a/libgo/go/net/http/fcgi/fcgi.go b/libgo/go/net/http/fcgi/fcgi.go
index 5057d70..8f3449a 100644
--- a/libgo/go/net/http/fcgi/fcgi.go
+++ b/libgo/go/net/http/fcgi/fcgi.go
@@ -24,7 +24,7 @@
 )
 
 // recType is a record type, as defined by
-// http://www.fastcgi.com/devkit/doc/fcgi-spec.html#S8
+// https://web.archive.org/web/20150420080736/http://www.fastcgi.com/drupal/node/6?q=node/22#S8
 type recType uint8
 
 const (
diff --git a/libgo/go/net/http/fcgi/fcgi_test.go b/libgo/go/net/http/fcgi/fcgi_test.go
index b6013bf..e9d2b34 100644
--- a/libgo/go/net/http/fcgi/fcgi_test.go
+++ b/libgo/go/net/http/fcgi/fcgi_test.go
@@ -278,3 +278,69 @@
 	c := newChild(rw, http.DefaultServeMux)
 	c.serve()
 }
+
+// a series of FastCGI records that start and end a request
+var streamFullRequestStdin = bytes.Join([][]byte{
+	// set up request
+	makeRecord(typeBeginRequest, 1,
+		[]byte{0, byte(roleResponder), 0, 0, 0, 0, 0, 0}),
+	// add required parameters
+	makeRecord(typeParams, 1, nameValuePair11("REQUEST_METHOD", "GET")),
+	makeRecord(typeParams, 1, nameValuePair11("SERVER_PROTOCOL", "HTTP/1.1")),
+	// set optional parameters
+	makeRecord(typeParams, 1, nameValuePair11("REMOTE_USER", "jane.doe")),
+	makeRecord(typeParams, 1, nameValuePair11("QUERY_STRING", "/foo/bar")),
+	makeRecord(typeParams, 1, nil),
+	// begin sending body of request
+	makeRecord(typeStdin, 1, []byte("0123456789abcdef")),
+	// end request
+	makeRecord(typeEndRequest, 1, nil),
+},
+	nil)
+
+var envVarTests = []struct {
+	input               []byte
+	envVar              string
+	expectedVal         string
+	expectedFilteredOut bool
+}{
+	{
+		streamFullRequestStdin,
+		"REMOTE_USER",
+		"jane.doe",
+		false,
+	},
+	{
+		streamFullRequestStdin,
+		"QUERY_STRING",
+		"",
+		true,
+	},
+}
+
+// Test that environment variables set for a request can be
+// read by a handler. Ensures that variables not set will not
+// be exposed to a handler.
+func TestChildServeReadsEnvVars(t *testing.T) {
+	for _, tt := range envVarTests {
+		input := make([]byte, len(tt.input))
+		copy(input, tt.input)
+		rc := nopWriteCloser{bytes.NewBuffer(input)}
+		done := make(chan bool)
+		c := newChild(rc, http.HandlerFunc(func(
+			w http.ResponseWriter,
+			r *http.Request,
+		) {
+			env := ProcessEnv(r)
+			if _, ok := env[tt.envVar]; ok && tt.expectedFilteredOut {
+				t.Errorf("Expected environment variable %s to not be set, but set to %s",
+					tt.envVar, env[tt.envVar])
+			} else if env[tt.envVar] != tt.expectedVal {
+				t.Errorf("Expected %s, got %s", tt.expectedVal, env[tt.envVar])
+			}
+			done <- true
+		}))
+		go c.serve()
+		<-done
+	}
+}
diff --git a/libgo/go/net/http/filetransport_test.go b/libgo/go/net/http/filetransport_test.go
index 6f1a537..2a2f32c 100644
--- a/libgo/go/net/http/filetransport_test.go
+++ b/libgo/go/net/http/filetransport_test.go
@@ -49,6 +49,7 @@
 			t.Fatalf("for %s, nil Body", urlstr)
 		}
 		slurp, err := ioutil.ReadAll(res.Body)
+		res.Body.Close()
 		check("ReadAll "+urlstr, err)
 		if string(slurp) != "Bar" {
 			t.Errorf("for %s, got content %q, want %q", urlstr, string(slurp), "Bar")
diff --git a/libgo/go/net/http/fs.go b/libgo/go/net/http/fs.go
index bf63bb5..5819334 100644
--- a/libgo/go/net/http/fs.go
+++ b/libgo/go/net/http/fs.go
@@ -30,21 +30,51 @@
 // value is a filename on the native file system, not a URL, so it is separated
 // by filepath.Separator, which isn't necessarily '/'.
 //
+// Note that Dir will allow access to files and directories starting with a
+// period, which could expose sensitive directories like a .git directory or
+// sensitive files like .htpasswd. To exclude files with a leading period,
+// remove the files/directories from the server or create a custom FileSystem
+// implementation.
+//
 // An empty Dir is treated as ".".
 type Dir string
 
+// mapDirOpenError maps the provided non-nil error from opening name
+// to a possibly better non-nil error. In particular, it turns OS-specific errors
+// about opening files in non-directories into os.ErrNotExist. See Issue 18984.
+func mapDirOpenError(originalErr error, name string) error {
+	if os.IsNotExist(originalErr) || os.IsPermission(originalErr) {
+		return originalErr
+	}
+
+	parts := strings.Split(name, string(filepath.Separator))
+	for i := range parts {
+		if parts[i] == "" {
+			continue
+		}
+		fi, err := os.Stat(strings.Join(parts[:i+1], string(filepath.Separator)))
+		if err != nil {
+			return originalErr
+		}
+		if !fi.IsDir() {
+			return os.ErrNotExist
+		}
+	}
+	return originalErr
+}
+
 func (d Dir) Open(name string) (File, error) {
-	if filepath.Separator != '/' && strings.ContainsRune(name, filepath.Separator) ||
-		strings.Contains(name, "\x00") {
+	if filepath.Separator != '/' && strings.ContainsRune(name, filepath.Separator) {
 		return nil, errors.New("http: invalid character in file path")
 	}
 	dir := string(d)
 	if dir == "" {
 		dir = "."
 	}
-	f, err := os.Open(filepath.Join(dir, filepath.FromSlash(path.Clean("/"+name))))
+	fullName := filepath.Join(dir, filepath.FromSlash(path.Clean("/"+name)))
+	f, err := os.Open(fullName)
 	if err != nil {
-		return nil, err
+		return nil, mapDirOpenError(err, fullName)
 	}
 	return f, nil
 }
@@ -291,7 +321,7 @@
 		case c == '"':
 			return string(s[:i+1]), s[i+1:]
 		default:
-			break
+			return "", ""
 		}
 	}
 	return "", ""
@@ -349,7 +379,7 @@
 	return condFalse
 }
 
-func checkIfUnmodifiedSince(w ResponseWriter, r *Request, modtime time.Time) condResult {
+func checkIfUnmodifiedSince(r *Request, modtime time.Time) condResult {
 	ius := r.Header.Get("If-Unmodified-Since")
 	if ius == "" || isZeroTime(modtime) {
 		return condNone
@@ -394,7 +424,7 @@
 	return condTrue
 }
 
-func checkIfModifiedSince(w ResponseWriter, r *Request, modtime time.Time) condResult {
+func checkIfModifiedSince(r *Request, modtime time.Time) condResult {
 	if r.Method != "GET" && r.Method != "HEAD" {
 		return condNone
 	}
@@ -479,7 +509,7 @@
 	// This function carefully follows RFC 7232 section 6.
 	ch := checkIfMatch(w, r)
 	if ch == condNone {
-		ch = checkIfUnmodifiedSince(w, r, modtime)
+		ch = checkIfUnmodifiedSince(r, modtime)
 	}
 	if ch == condFalse {
 		w.WriteHeader(StatusPreconditionFailed)
@@ -495,7 +525,7 @@
 			return true, ""
 		}
 	case condNone:
-		if checkIfModifiedSince(w, r, modtime) == condFalse {
+		if checkIfModifiedSince(r, modtime) == condFalse {
 			writeNotModified(w)
 			return true, ""
 		}
@@ -580,7 +610,7 @@
 
 	// Still a directory? (we didn't find an index.html file)
 	if d.IsDir() {
-		if checkIfModifiedSince(w, r, d.ModTime()) == condFalse {
+		if checkIfModifiedSince(r, d.ModTime()) == condFalse {
 			writeNotModified(w)
 			return
 		}
diff --git a/libgo/go/net/http/fs_test.go b/libgo/go/net/http/fs_test.go
index bba5682..f6eab0f 100644
--- a/libgo/go/net/http/fs_test.go
+++ b/libgo/go/net/http/fs_test.go
@@ -74,6 +74,7 @@
 		ServeFile(w, r, "testdata/file")
 	}))
 	defer ts.Close()
+	c := ts.Client()
 
 	var err error
 
@@ -91,7 +92,7 @@
 	req.Method = "GET"
 
 	// straight GET
-	_, body := getBody(t, "straight get", req)
+	_, body := getBody(t, "straight get", req, c)
 	if !bytes.Equal(body, file) {
 		t.Fatalf("body mismatch: got %q, want %q", body, file)
 	}
@@ -102,7 +103,7 @@
 		if rt.r != "" {
 			req.Header.Set("Range", rt.r)
 		}
-		resp, body := getBody(t, fmt.Sprintf("range test %q", rt.r), req)
+		resp, body := getBody(t, fmt.Sprintf("range test %q", rt.r), req, c)
 		if resp.StatusCode != rt.code {
 			t.Errorf("range=%q: StatusCode=%d, want %d", rt.r, resp.StatusCode, rt.code)
 		}
@@ -704,7 +705,8 @@
 	req, _ := NewRequest("GET", ts.URL, nil)
 	req.Header.Set("If-Modified-Since", lastMod)
 
-	res, err = DefaultClient.Do(req)
+	c := ts.Client()
+	res, err = c.Do(req)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -716,7 +718,7 @@
 	// Advance the index.html file's modtime, but not the directory's.
 	indexFile.modtime = indexFile.modtime.Add(1 * time.Hour)
 
-	res, err = DefaultClient.Do(req)
+	res, err = c.Do(req)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -995,7 +997,9 @@
 		for k, v := range tt.reqHeader {
 			req.Header.Set(k, v)
 		}
-		res, err := DefaultClient.Do(req)
+
+		c := ts.Client()
+		res, err := c.Do(req)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -1050,8 +1054,9 @@
 	}
 	ts := httptest.NewServer(FileServer(fs))
 	defer ts.Close()
+	c := ts.Client()
 	for _, code := range []int{403, 404, 500} {
-		res, err := DefaultClient.Get(fmt.Sprintf("%s/%d", ts.URL, code))
+		res, err := c.Get(fmt.Sprintf("%s/%d", ts.URL, code))
 		if err != nil {
 			t.Errorf("Error fetching /%d: %v", code, err)
 			continue
@@ -1090,8 +1095,11 @@
 		// strace on the above platforms doesn't support sendfile64
 		// and will error out if we specify that with `-e trace='.
 		syscalls = "sendfile"
-	case "mips64":
-		t.Skip("TODO: update this test to be robust against various versions of strace on mips64. See golang.org/issue/33430")
+	}
+
+	// Attempt to run strace, and skip on failure - this test requires SYS_PTRACE.
+	if err := exec.Command("strace", "-f", "-q", "-e", "trace="+syscalls, os.Args[0], "-test.run=^$").Run(); err != nil {
+		t.Skipf("skipping; failed to run strace: %v", err)
 	}
 
 	var buf bytes.Buffer
@@ -1125,8 +1133,8 @@
 	}
 }
 
-func getBody(t *testing.T, testName string, req Request) (*Response, []byte) {
-	r, err := DefaultClient.Do(&req)
+func getBody(t *testing.T, testName string, req Request, client *Client) (*Response, []byte) {
+	r, err := client.Do(&req)
 	if err != nil {
 		t.Fatalf("%s: for URL %q, send error: %v", testName, req.URL.String(), err)
 	}
@@ -1161,6 +1169,50 @@
 	}
 }
 
+// Issue 18984: tests that requests for paths beyond files return not-found errors
+func TestFileServerNotDirError(t *testing.T) {
+	defer afterTest(t)
+	ts := httptest.NewServer(FileServer(Dir("testdata")))
+	defer ts.Close()
+
+	res, err := Get(ts.URL + "/index.html/not-a-file")
+	if err != nil {
+		t.Fatal(err)
+	}
+	res.Body.Close()
+	if res.StatusCode != 404 {
+		t.Errorf("StatusCode = %v; want 404", res.StatusCode)
+	}
+
+	test := func(name string, dir Dir) {
+		t.Run(name, func(t *testing.T) {
+			_, err = dir.Open("/index.html/not-a-file")
+			if err == nil {
+				t.Fatal("err == nil; want != nil")
+			}
+			if !os.IsNotExist(err) {
+				t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
+			}
+
+			_, err = dir.Open("/index.html/not-a-dir/not-a-file")
+			if err == nil {
+				t.Fatal("err == nil; want != nil")
+			}
+			if !os.IsNotExist(err) {
+				t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
+			}
+		})
+	}
+
+	absPath, err := filepath.Abs("testdata")
+	if err != nil {
+		t.Fatal("get abs path:", err)
+	}
+
+	test("RelativePath", Dir("testdata"))
+	test("AbsolutePath", Dir(absPath))
+}
+
 func TestFileServerCleanPath(t *testing.T) {
 	tests := []struct {
 		path     string
@@ -1210,10 +1262,10 @@
 		{`"etag-2"`, `"etag-2"`, ""},
 		{`"etag-1", "etag-2"`, `"etag-1"`, `, "etag-2"`},
 		{"", "", ""},
-		{"", "", ""},
 		{"W/", "", ""},
 		{`W/"truc`, "", ""},
 		{`w/"case-sensitive"`, "", ""},
+		{`"spaced etag"`, "", ""},
 	}
 	for _, test := range tests {
 		etag, remain := ExportScanETag(test.in)
diff --git a/libgo/go/net/http/h2_bundle.go b/libgo/go/net/http/h2_bundle.go
index 6fbbcd0..373f550 100644
--- a/libgo/go/net/http/h2_bundle.go
+++ b/libgo/go/net/http/h2_bundle.go
@@ -48,6 +48,642 @@
 	"golang_org/x/net/lex/httplex"
 )
 
+// A list of the possible cipher suite ids. Taken from
+// http://www.iana.org/assignments/tls-parameters/tls-parameters.txt
+
+const (
+	http2cipher_TLS_NULL_WITH_NULL_NULL               uint16 = 0x0000
+	http2cipher_TLS_RSA_WITH_NULL_MD5                 uint16 = 0x0001
+	http2cipher_TLS_RSA_WITH_NULL_SHA                 uint16 = 0x0002
+	http2cipher_TLS_RSA_EXPORT_WITH_RC4_40_MD5        uint16 = 0x0003
+	http2cipher_TLS_RSA_WITH_RC4_128_MD5              uint16 = 0x0004
+	http2cipher_TLS_RSA_WITH_RC4_128_SHA              uint16 = 0x0005
+	http2cipher_TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5    uint16 = 0x0006
+	http2cipher_TLS_RSA_WITH_IDEA_CBC_SHA             uint16 = 0x0007
+	http2cipher_TLS_RSA_EXPORT_WITH_DES40_CBC_SHA     uint16 = 0x0008
+	http2cipher_TLS_RSA_WITH_DES_CBC_SHA              uint16 = 0x0009
+	http2cipher_TLS_RSA_WITH_3DES_EDE_CBC_SHA         uint16 = 0x000A
+	http2cipher_TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA  uint16 = 0x000B
+	http2cipher_TLS_DH_DSS_WITH_DES_CBC_SHA           uint16 = 0x000C
+	http2cipher_TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA      uint16 = 0x000D
+	http2cipher_TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA  uint16 = 0x000E
+	http2cipher_TLS_DH_RSA_WITH_DES_CBC_SHA           uint16 = 0x000F
+	http2cipher_TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA      uint16 = 0x0010
+	http2cipher_TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0011
+	http2cipher_TLS_DHE_DSS_WITH_DES_CBC_SHA          uint16 = 0x0012
+	http2cipher_TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA     uint16 = 0x0013
+	http2cipher_TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0014
+	http2cipher_TLS_DHE_RSA_WITH_DES_CBC_SHA          uint16 = 0x0015
+	http2cipher_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA     uint16 = 0x0016
+	http2cipher_TLS_DH_anon_EXPORT_WITH_RC4_40_MD5    uint16 = 0x0017
+	http2cipher_TLS_DH_anon_WITH_RC4_128_MD5          uint16 = 0x0018
+	http2cipher_TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0019
+	http2cipher_TLS_DH_anon_WITH_DES_CBC_SHA          uint16 = 0x001A
+	http2cipher_TLS_DH_anon_WITH_3DES_EDE_CBC_SHA     uint16 = 0x001B
+	// Reserved uint16 =  0x001C-1D
+	http2cipher_TLS_KRB5_WITH_DES_CBC_SHA             uint16 = 0x001E
+	http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_SHA        uint16 = 0x001F
+	http2cipher_TLS_KRB5_WITH_RC4_128_SHA             uint16 = 0x0020
+	http2cipher_TLS_KRB5_WITH_IDEA_CBC_SHA            uint16 = 0x0021
+	http2cipher_TLS_KRB5_WITH_DES_CBC_MD5             uint16 = 0x0022
+	http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_MD5        uint16 = 0x0023
+	http2cipher_TLS_KRB5_WITH_RC4_128_MD5             uint16 = 0x0024
+	http2cipher_TLS_KRB5_WITH_IDEA_CBC_MD5            uint16 = 0x0025
+	http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_SHA   uint16 = 0x0026
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_SHA   uint16 = 0x0027
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_SHA       uint16 = 0x0028
+	http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_MD5   uint16 = 0x0029
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_MD5   uint16 = 0x002A
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_MD5       uint16 = 0x002B
+	http2cipher_TLS_PSK_WITH_NULL_SHA                 uint16 = 0x002C
+	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA             uint16 = 0x002D
+	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA             uint16 = 0x002E
+	http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA          uint16 = 0x002F
+	http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA       uint16 = 0x0030
+	http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA       uint16 = 0x0031
+	http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA      uint16 = 0x0032
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA      uint16 = 0x0033
+	http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA      uint16 = 0x0034
+	http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA          uint16 = 0x0035
+	http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA       uint16 = 0x0036
+	http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA       uint16 = 0x0037
+	http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA      uint16 = 0x0038
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA      uint16 = 0x0039
+	http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA      uint16 = 0x003A
+	http2cipher_TLS_RSA_WITH_NULL_SHA256              uint16 = 0x003B
+	http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA256       uint16 = 0x003C
+	http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA256       uint16 = 0x003D
+	http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA256    uint16 = 0x003E
+	http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA256    uint16 = 0x003F
+	http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA256   uint16 = 0x0040
+	http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA     uint16 = 0x0041
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA  uint16 = 0x0042
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA  uint16 = 0x0043
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0044
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0045
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0046
+	// Reserved uint16 =  0x0047-4F
+	// Reserved uint16 =  0x0050-58
+	// Reserved uint16 =  0x0059-5C
+	// Unassigned uint16 =  0x005D-5F
+	// Reserved uint16 =  0x0060-66
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 uint16 = 0x0067
+	http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA256  uint16 = 0x0068
+	http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA256  uint16 = 0x0069
+	http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 uint16 = 0x006A
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 uint16 = 0x006B
+	http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA256 uint16 = 0x006C
+	http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA256 uint16 = 0x006D
+	// Unassigned uint16 =  0x006E-83
+	http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA        uint16 = 0x0084
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA     uint16 = 0x0085
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA     uint16 = 0x0086
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0087
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0088
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0089
+	http2cipher_TLS_PSK_WITH_RC4_128_SHA                 uint16 = 0x008A
+	http2cipher_TLS_PSK_WITH_3DES_EDE_CBC_SHA            uint16 = 0x008B
+	http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA             uint16 = 0x008C
+	http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA             uint16 = 0x008D
+	http2cipher_TLS_DHE_PSK_WITH_RC4_128_SHA             uint16 = 0x008E
+	http2cipher_TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA        uint16 = 0x008F
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA         uint16 = 0x0090
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA         uint16 = 0x0091
+	http2cipher_TLS_RSA_PSK_WITH_RC4_128_SHA             uint16 = 0x0092
+	http2cipher_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA        uint16 = 0x0093
+	http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA         uint16 = 0x0094
+	http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA         uint16 = 0x0095
+	http2cipher_TLS_RSA_WITH_SEED_CBC_SHA                uint16 = 0x0096
+	http2cipher_TLS_DH_DSS_WITH_SEED_CBC_SHA             uint16 = 0x0097
+	http2cipher_TLS_DH_RSA_WITH_SEED_CBC_SHA             uint16 = 0x0098
+	http2cipher_TLS_DHE_DSS_WITH_SEED_CBC_SHA            uint16 = 0x0099
+	http2cipher_TLS_DHE_RSA_WITH_SEED_CBC_SHA            uint16 = 0x009A
+	http2cipher_TLS_DH_anon_WITH_SEED_CBC_SHA            uint16 = 0x009B
+	http2cipher_TLS_RSA_WITH_AES_128_GCM_SHA256          uint16 = 0x009C
+	http2cipher_TLS_RSA_WITH_AES_256_GCM_SHA384          uint16 = 0x009D
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_GCM_SHA256      uint16 = 0x009E
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_GCM_SHA384      uint16 = 0x009F
+	http2cipher_TLS_DH_RSA_WITH_AES_128_GCM_SHA256       uint16 = 0x00A0
+	http2cipher_TLS_DH_RSA_WITH_AES_256_GCM_SHA384       uint16 = 0x00A1
+	http2cipher_TLS_DHE_DSS_WITH_AES_128_GCM_SHA256      uint16 = 0x00A2
+	http2cipher_TLS_DHE_DSS_WITH_AES_256_GCM_SHA384      uint16 = 0x00A3
+	http2cipher_TLS_DH_DSS_WITH_AES_128_GCM_SHA256       uint16 = 0x00A4
+	http2cipher_TLS_DH_DSS_WITH_AES_256_GCM_SHA384       uint16 = 0x00A5
+	http2cipher_TLS_DH_anon_WITH_AES_128_GCM_SHA256      uint16 = 0x00A6
+	http2cipher_TLS_DH_anon_WITH_AES_256_GCM_SHA384      uint16 = 0x00A7
+	http2cipher_TLS_PSK_WITH_AES_128_GCM_SHA256          uint16 = 0x00A8
+	http2cipher_TLS_PSK_WITH_AES_256_GCM_SHA384          uint16 = 0x00A9
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_GCM_SHA256      uint16 = 0x00AA
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_GCM_SHA384      uint16 = 0x00AB
+	http2cipher_TLS_RSA_PSK_WITH_AES_128_GCM_SHA256      uint16 = 0x00AC
+	http2cipher_TLS_RSA_PSK_WITH_AES_256_GCM_SHA384      uint16 = 0x00AD
+	http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA256          uint16 = 0x00AE
+	http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA384          uint16 = 0x00AF
+	http2cipher_TLS_PSK_WITH_NULL_SHA256                 uint16 = 0x00B0
+	http2cipher_TLS_PSK_WITH_NULL_SHA384                 uint16 = 0x00B1
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA256      uint16 = 0x00B2
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA384      uint16 = 0x00B3
+	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA256             uint16 = 0x00B4
+	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA384             uint16 = 0x00B5
+	http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA256      uint16 = 0x00B6
+	http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA384      uint16 = 0x00B7
+	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA256             uint16 = 0x00B8
+	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA384             uint16 = 0x00B9
+	http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0x00BA
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0x00BB
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0x00BC
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BD
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BE
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BF
+	http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256     uint16 = 0x00C0
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA256  uint16 = 0x00C1
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA256  uint16 = 0x00C2
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C3
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C4
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C5
+	// Unassigned uint16 =  0x00C6-FE
+	http2cipher_TLS_EMPTY_RENEGOTIATION_INFO_SCSV uint16 = 0x00FF
+	// Unassigned uint16 =  0x01-55,*
+	http2cipher_TLS_FALLBACK_SCSV uint16 = 0x5600
+	// Unassigned                                   uint16 = 0x5601 - 0xC000
+	http2cipher_TLS_ECDH_ECDSA_WITH_NULL_SHA                 uint16 = 0xC001
+	http2cipher_TLS_ECDH_ECDSA_WITH_RC4_128_SHA              uint16 = 0xC002
+	http2cipher_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA         uint16 = 0xC003
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA          uint16 = 0xC004
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA          uint16 = 0xC005
+	http2cipher_TLS_ECDHE_ECDSA_WITH_NULL_SHA                uint16 = 0xC006
+	http2cipher_TLS_ECDHE_ECDSA_WITH_RC4_128_SHA             uint16 = 0xC007
+	http2cipher_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC008
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA         uint16 = 0xC009
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA         uint16 = 0xC00A
+	http2cipher_TLS_ECDH_RSA_WITH_NULL_SHA                   uint16 = 0xC00B
+	http2cipher_TLS_ECDH_RSA_WITH_RC4_128_SHA                uint16 = 0xC00C
+	http2cipher_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA           uint16 = 0xC00D
+	http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA            uint16 = 0xC00E
+	http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA            uint16 = 0xC00F
+	http2cipher_TLS_ECDHE_RSA_WITH_NULL_SHA                  uint16 = 0xC010
+	http2cipher_TLS_ECDHE_RSA_WITH_RC4_128_SHA               uint16 = 0xC011
+	http2cipher_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC012
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA           uint16 = 0xC013
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA           uint16 = 0xC014
+	http2cipher_TLS_ECDH_anon_WITH_NULL_SHA                  uint16 = 0xC015
+	http2cipher_TLS_ECDH_anon_WITH_RC4_128_SHA               uint16 = 0xC016
+	http2cipher_TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC017
+	http2cipher_TLS_ECDH_anon_WITH_AES_128_CBC_SHA           uint16 = 0xC018
+	http2cipher_TLS_ECDH_anon_WITH_AES_256_CBC_SHA           uint16 = 0xC019
+	http2cipher_TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA            uint16 = 0xC01A
+	http2cipher_TLS_SRP_SHA_RSA_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC01B
+	http2cipher_TLS_SRP_SHA_DSS_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC01C
+	http2cipher_TLS_SRP_SHA_WITH_AES_128_CBC_SHA             uint16 = 0xC01D
+	http2cipher_TLS_SRP_SHA_RSA_WITH_AES_128_CBC_SHA         uint16 = 0xC01E
+	http2cipher_TLS_SRP_SHA_DSS_WITH_AES_128_CBC_SHA         uint16 = 0xC01F
+	http2cipher_TLS_SRP_SHA_WITH_AES_256_CBC_SHA             uint16 = 0xC020
+	http2cipher_TLS_SRP_SHA_RSA_WITH_AES_256_CBC_SHA         uint16 = 0xC021
+	http2cipher_TLS_SRP_SHA_DSS_WITH_AES_256_CBC_SHA         uint16 = 0xC022
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256      uint16 = 0xC023
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384      uint16 = 0xC024
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256       uint16 = 0xC025
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384       uint16 = 0xC026
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256        uint16 = 0xC027
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384        uint16 = 0xC028
+	http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256         uint16 = 0xC029
+	http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384         uint16 = 0xC02A
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256      uint16 = 0xC02B
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384      uint16 = 0xC02C
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256       uint16 = 0xC02D
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384       uint16 = 0xC02E
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256        uint16 = 0xC02F
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384        uint16 = 0xC030
+	http2cipher_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256         uint16 = 0xC031
+	http2cipher_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384         uint16 = 0xC032
+	http2cipher_TLS_ECDHE_PSK_WITH_RC4_128_SHA               uint16 = 0xC033
+	http2cipher_TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC034
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA           uint16 = 0xC035
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA           uint16 = 0xC036
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256        uint16 = 0xC037
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384        uint16 = 0xC038
+	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA                  uint16 = 0xC039
+	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA256               uint16 = 0xC03A
+	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA384               uint16 = 0xC03B
+	http2cipher_TLS_RSA_WITH_ARIA_128_CBC_SHA256             uint16 = 0xC03C
+	http2cipher_TLS_RSA_WITH_ARIA_256_CBC_SHA384             uint16 = 0xC03D
+	http2cipher_TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256          uint16 = 0xC03E
+	http2cipher_TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384          uint16 = 0xC03F
+	http2cipher_TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256          uint16 = 0xC040
+	http2cipher_TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384          uint16 = 0xC041
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC042
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC043
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC044
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC045
+	http2cipher_TLS_DH_anon_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC046
+	http2cipher_TLS_DH_anon_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC047
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256     uint16 = 0xC048
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384     uint16 = 0xC049
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256      uint16 = 0xC04A
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384      uint16 = 0xC04B
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256       uint16 = 0xC04C
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384       uint16 = 0xC04D
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256        uint16 = 0xC04E
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384        uint16 = 0xC04F
+	http2cipher_TLS_RSA_WITH_ARIA_128_GCM_SHA256             uint16 = 0xC050
+	http2cipher_TLS_RSA_WITH_ARIA_256_GCM_SHA384             uint16 = 0xC051
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC052
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC053
+	http2cipher_TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256          uint16 = 0xC054
+	http2cipher_TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384          uint16 = 0xC055
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC056
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC057
+	http2cipher_TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256          uint16 = 0xC058
+	http2cipher_TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384          uint16 = 0xC059
+	http2cipher_TLS_DH_anon_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC05A
+	http2cipher_TLS_DH_anon_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC05B
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_GCM_SHA256     uint16 = 0xC05C
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_GCM_SHA384     uint16 = 0xC05D
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256      uint16 = 0xC05E
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384      uint16 = 0xC05F
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_GCM_SHA256       uint16 = 0xC060
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_GCM_SHA384       uint16 = 0xC061
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256        uint16 = 0xC062
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384        uint16 = 0xC063
+	http2cipher_TLS_PSK_WITH_ARIA_128_CBC_SHA256             uint16 = 0xC064
+	http2cipher_TLS_PSK_WITH_ARIA_256_CBC_SHA384             uint16 = 0xC065
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC066
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC067
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC068
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC069
+	http2cipher_TLS_PSK_WITH_ARIA_128_GCM_SHA256             uint16 = 0xC06A
+	http2cipher_TLS_PSK_WITH_ARIA_256_GCM_SHA384             uint16 = 0xC06B
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC06C
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC06D
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC06E
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC06F
+	http2cipher_TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256       uint16 = 0xC070
+	http2cipher_TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384       uint16 = 0xC071
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0xC072
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384 uint16 = 0xC073
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0xC074
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_CBC_SHA384  uint16 = 0xC075
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256   uint16 = 0xC076
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384   uint16 = 0xC077
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_CBC_SHA256    uint16 = 0xC078
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_CBC_SHA384    uint16 = 0xC079
+	http2cipher_TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256         uint16 = 0xC07A
+	http2cipher_TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384         uint16 = 0xC07B
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC07C
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC07D
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_GCM_SHA256      uint16 = 0xC07E
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_GCM_SHA384      uint16 = 0xC07F
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC080
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC081
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_GCM_SHA256      uint16 = 0xC082
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_GCM_SHA384      uint16 = 0xC083
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC084
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC085
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_GCM_SHA256 uint16 = 0xC086
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_GCM_SHA384 uint16 = 0xC087
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_GCM_SHA256  uint16 = 0xC088
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_GCM_SHA384  uint16 = 0xC089
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_GCM_SHA256   uint16 = 0xC08A
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_GCM_SHA384   uint16 = 0xC08B
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_GCM_SHA256    uint16 = 0xC08C
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_GCM_SHA384    uint16 = 0xC08D
+	http2cipher_TLS_PSK_WITH_CAMELLIA_128_GCM_SHA256         uint16 = 0xC08E
+	http2cipher_TLS_PSK_WITH_CAMELLIA_256_GCM_SHA384         uint16 = 0xC08F
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC090
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC091
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC092
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC093
+	http2cipher_TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256         uint16 = 0xC094
+	http2cipher_TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384         uint16 = 0xC095
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0xC096
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384     uint16 = 0xC097
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0xC098
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384     uint16 = 0xC099
+	http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256   uint16 = 0xC09A
+	http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384   uint16 = 0xC09B
+	http2cipher_TLS_RSA_WITH_AES_128_CCM                     uint16 = 0xC09C
+	http2cipher_TLS_RSA_WITH_AES_256_CCM                     uint16 = 0xC09D
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CCM                 uint16 = 0xC09E
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CCM                 uint16 = 0xC09F
+	http2cipher_TLS_RSA_WITH_AES_128_CCM_8                   uint16 = 0xC0A0
+	http2cipher_TLS_RSA_WITH_AES_256_CCM_8                   uint16 = 0xC0A1
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CCM_8               uint16 = 0xC0A2
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CCM_8               uint16 = 0xC0A3
+	http2cipher_TLS_PSK_WITH_AES_128_CCM                     uint16 = 0xC0A4
+	http2cipher_TLS_PSK_WITH_AES_256_CCM                     uint16 = 0xC0A5
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_CCM                 uint16 = 0xC0A6
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_CCM                 uint16 = 0xC0A7
+	http2cipher_TLS_PSK_WITH_AES_128_CCM_8                   uint16 = 0xC0A8
+	http2cipher_TLS_PSK_WITH_AES_256_CCM_8                   uint16 = 0xC0A9
+	http2cipher_TLS_PSK_DHE_WITH_AES_128_CCM_8               uint16 = 0xC0AA
+	http2cipher_TLS_PSK_DHE_WITH_AES_256_CCM_8               uint16 = 0xC0AB
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CCM             uint16 = 0xC0AC
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CCM             uint16 = 0xC0AD
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8           uint16 = 0xC0AE
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8           uint16 = 0xC0AF
+	// Unassigned uint16 =  0xC0B0-FF
+	// Unassigned uint16 =  0xC1-CB,*
+	// Unassigned uint16 =  0xCC00-A7
+	http2cipher_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xCCA8
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 uint16 = 0xCCA9
+	http2cipher_TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAA
+	http2cipher_TLS_PSK_WITH_CHACHA20_POLY1305_SHA256         uint16 = 0xCCAB
+	http2cipher_TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xCCAC
+	http2cipher_TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAD
+	http2cipher_TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAE
+)
+
+// isBadCipher reports whether the cipher is blacklisted by the HTTP/2 spec.
+// References:
+// https://tools.ietf.org/html/rfc7540#appendix-A
+// Reject cipher suites from Appendix A.
+// "This list includes those cipher suites that do not
+// offer an ephemeral key exchange and those that are
+// based on the TLS null, stream or block cipher type"
+func http2isBadCipher(cipher uint16) bool {
+	switch cipher {
+	case http2cipher_TLS_NULL_WITH_NULL_NULL,
+		http2cipher_TLS_RSA_WITH_NULL_MD5,
+		http2cipher_TLS_RSA_WITH_NULL_SHA,
+		http2cipher_TLS_RSA_EXPORT_WITH_RC4_40_MD5,
+		http2cipher_TLS_RSA_WITH_RC4_128_MD5,
+		http2cipher_TLS_RSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5,
+		http2cipher_TLS_RSA_WITH_IDEA_CBC_SHA,
+		http2cipher_TLS_RSA_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_DES_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DH_anon_EXPORT_WITH_RC4_40_MD5,
+		http2cipher_TLS_DH_anon_WITH_RC4_128_MD5,
+		http2cipher_TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_DES_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_RC4_128_SHA,
+		http2cipher_TLS_KRB5_WITH_IDEA_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_DES_CBC_MD5,
+		http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_MD5,
+		http2cipher_TLS_KRB5_WITH_RC4_128_MD5,
+		http2cipher_TLS_KRB5_WITH_IDEA_CBC_MD5,
+		http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_SHA,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_SHA,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_SHA,
+		http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_MD5,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_MD5,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_MD5,
+		http2cipher_TLS_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_NULL_SHA256,
+		http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_RSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_DH_anon_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_DH_anon_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_PSK_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_EMPTY_RENEGOTIATION_INFO_SCSV,
+		http2cipher_TLS_ECDH_ECDSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_NULL_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_DSS_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_DSS_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_DSS_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DH_anon_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_anon_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_anon_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_PSK_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_PSK_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_WITH_AES_128_CCM,
+		http2cipher_TLS_RSA_WITH_AES_256_CCM,
+		http2cipher_TLS_RSA_WITH_AES_128_CCM_8,
+		http2cipher_TLS_RSA_WITH_AES_256_CCM_8,
+		http2cipher_TLS_PSK_WITH_AES_128_CCM,
+		http2cipher_TLS_PSK_WITH_AES_256_CCM,
+		http2cipher_TLS_PSK_WITH_AES_128_CCM_8,
+		http2cipher_TLS_PSK_WITH_AES_256_CCM_8:
+		return true
+	default:
+		return false
+	}
+}
+
 // ClientConnPool manages a pool of HTTP/2 client connections.
 type http2ClientConnPool interface {
 	GetClientConn(req *Request, addr string) (*http2ClientConn, error)
@@ -126,7 +762,7 @@
 // requires p.mu is held.
 func (p *http2clientConnPool) getStartDialLocked(addr string) *http2dialCall {
 	if call, ok := p.dialing[addr]; ok {
-
+		// A dial is already in-flight. Don't start another.
 		return call
 	}
 	call := &http2dialCall{p: p, done: make(chan struct{})}
@@ -254,7 +890,12 @@
 func (p *http2clientConnPool) closeIdleConnections() {
 	p.mu.Lock()
 	defer p.mu.Unlock()
-
+	// TODO: don't close a cc if it was just added to the pool
+	// milliseconds ago and has never been used. There's currently
+	// a small race window with the HTTP/1 Transport's integration
+	// where it can add an idle conn just before using it, and
+	// somebody else can concurrently call CloseIdleConns and
+	// break some caller's RoundTrip.
 	for _, vv := range p.conns {
 		for _, cc := range vv {
 			cc.closeIfIdle()
@@ -269,7 +910,8 @@
 			out = append(out, v)
 		}
 	}
-
+	// If we filtered it out, zero out the last item to prevent
+	// the GC from seeing it.
 	if len(in) != len(out) {
 		in[len(in)-1] = nil
 	}
@@ -277,7 +919,7 @@
 }
 
 // noDialClientConnPool is an implementation of http2.ClientConnPool
-// which never dials.  We let the HTTP/1.1 client dial and use its TLS
+// which never dials. We let the HTTP/1.1 client dial and use its TLS
 // connection instead.
 type http2noDialClientConnPool struct{ *http2clientConnPool }
 
@@ -310,7 +952,10 @@
 			go c.Close()
 			return http2erringRoundTripper{err}
 		} else if !used {
-
+			// Turns out we don't need this c.
+			// For example, two goroutines made requests to the same host
+			// at the same time, both kicking off TCP dials. (since protocol
+			// was unknown)
 			go c.Close()
 		}
 		return t2
@@ -326,7 +971,7 @@
 }
 
 // registerHTTPSProtocol calls Transport.RegisterProtocol but
-// convering panics into errors.
+// converting panics into errors.
 func http2registerHTTPSProtocol(t *Transport, rt RoundTripper) (err error) {
 	defer func() {
 		if e := recover(); e != nil {
@@ -349,6 +994,141 @@
 	return res, err
 }
 
+// Buffer chunks are allocated from a pool to reduce pressure on GC.
+// The maximum wasted space per dataBuffer is 2x the largest size class,
+// which happens when the dataBuffer has multiple chunks and there is
+// one unread byte in both the first and last chunks. We use a few size
+// classes to minimize overheads for servers that typically receive very
+// small request bodies.
+//
+// TODO: Benchmark to determine if the pools are necessary. The GC may have
+// improved enough that we can instead allocate chunks like this:
+// make([]byte, max(16<<10, expectedBytesRemaining))
+var (
+	http2dataChunkSizeClasses = []int{
+		1 << 10,
+		2 << 10,
+		4 << 10,
+		8 << 10,
+		16 << 10,
+	}
+	http2dataChunkPools = [...]sync.Pool{
+		{New: func() interface{} { return make([]byte, 1<<10) }},
+		{New: func() interface{} { return make([]byte, 2<<10) }},
+		{New: func() interface{} { return make([]byte, 4<<10) }},
+		{New: func() interface{} { return make([]byte, 8<<10) }},
+		{New: func() interface{} { return make([]byte, 16<<10) }},
+	}
+)
+
+func http2getDataBufferChunk(size int64) []byte {
+	i := 0
+	for ; i < len(http2dataChunkSizeClasses)-1; i++ {
+		if size <= int64(http2dataChunkSizeClasses[i]) {
+			break
+		}
+	}
+	return http2dataChunkPools[i].Get().([]byte)
+}
+
+func http2putDataBufferChunk(p []byte) {
+	for i, n := range http2dataChunkSizeClasses {
+		if len(p) == n {
+			http2dataChunkPools[i].Put(p)
+			return
+		}
+	}
+	panic(fmt.Sprintf("unexpected buffer len=%v", len(p)))
+}
+
+// dataBuffer is an io.ReadWriter backed by a list of data chunks.
+// Each dataBuffer is used to read DATA frames on a single stream.
+// The buffer is divided into chunks so the server can limit the
+// total memory used by a single connection without limiting the
+// request body size on any single stream.
+type http2dataBuffer struct {
+	chunks   [][]byte
+	r        int   // next byte to read is chunks[0][r]
+	w        int   // next byte to write is chunks[len(chunks)-1][w]
+	size     int   // total buffered bytes
+	expected int64 // we expect at least this many bytes in future Write calls (ignored if <= 0)
+}
+
+var http2errReadEmpty = errors.New("read from empty dataBuffer")
+
+// Read copies bytes from the buffer into p.
+// It is an error to read when no data is available.
+func (b *http2dataBuffer) Read(p []byte) (int, error) {
+	if b.size == 0 {
+		return 0, http2errReadEmpty
+	}
+	var ntotal int
+	for len(p) > 0 && b.size > 0 {
+		readFrom := b.bytesFromFirstChunk()
+		n := copy(p, readFrom)
+		p = p[n:]
+		ntotal += n
+		b.r += n
+		b.size -= n
+		// If the first chunk has been consumed, advance to the next chunk.
+		if b.r == len(b.chunks[0]) {
+			http2putDataBufferChunk(b.chunks[0])
+			end := len(b.chunks) - 1
+			copy(b.chunks[:end], b.chunks[1:])
+			b.chunks[end] = nil
+			b.chunks = b.chunks[:end]
+			b.r = 0
+		}
+	}
+	return ntotal, nil
+}
+
+func (b *http2dataBuffer) bytesFromFirstChunk() []byte {
+	if len(b.chunks) == 1 {
+		return b.chunks[0][b.r:b.w]
+	}
+	return b.chunks[0][b.r:]
+}
+
+// Len returns the number of bytes of the unread portion of the buffer.
+func (b *http2dataBuffer) Len() int {
+	return b.size
+}
+
+// Write appends p to the buffer.
+func (b *http2dataBuffer) Write(p []byte) (int, error) {
+	ntotal := len(p)
+	for len(p) > 0 {
+		// If the last chunk is empty, allocate a new chunk. Try to allocate
+		// enough to fully copy p plus any additional bytes we expect to
+		// receive. However, this may allocate less than len(p).
+		want := int64(len(p))
+		if b.expected > want {
+			want = b.expected
+		}
+		chunk := b.lastChunkOrAlloc(want)
+		n := copy(chunk[b.w:], p)
+		p = p[n:]
+		b.w += n
+		b.size += n
+		b.expected -= int64(n)
+	}
+	return ntotal, nil
+}
+
+func (b *http2dataBuffer) lastChunkOrAlloc(want int64) []byte {
+	if len(b.chunks) != 0 {
+		last := b.chunks[len(b.chunks)-1]
+		if b.w < len(last) {
+			return last
+		}
+	}
+	chunk := http2getDataBufferChunk(want)
+	b.chunks = append(b.chunks, chunk)
+	b.w = 0
+	return chunk
+}
+
 // An ErrCode is an unsigned 32-bit error code as defined in the HTTP/2 spec.
 type http2ErrCode uint32
 
@@ -429,11 +1209,16 @@
 
 func (http2goAwayFlowError) Error() string { return "connection exceeded flow control window size" }
 
+// connError represents an HTTP/2 ConnectionError error code, along
+// with a string (for debugging) explaining why.
+//
 // Errors of this type are only returned by the frame parser functions
-// and converted into ConnectionError(ErrCodeProtocol).
+// and converted into ConnectionError(Code), after stashing away
+// the Reason into the Framer's errDetail field, accessible via
+// the (*Framer).ErrorDetail method.
 type http2connError struct {
-	Code   http2ErrCode
-	Reason string
+	Code   http2ErrCode // the ConnectionError error code
+	Reason string       // additional reason
 }
 
 func (e http2connError) Error() string {
@@ -469,56 +1254,6 @@
 	http2errPseudoAfterRegular   = errors.New("pseudo header field after regular")
 )
 
-// fixedBuffer is an io.ReadWriter backed by a fixed size buffer.
-// It never allocates, but moves old data as new data is written.
-type http2fixedBuffer struct {
-	buf  []byte
-	r, w int
-}
-
-var (
-	http2errReadEmpty = errors.New("read from empty fixedBuffer")
-	http2errWriteFull = errors.New("write on full fixedBuffer")
-)
-
-// Read copies bytes from the buffer into p.
-// It is an error to read when no data is available.
-func (b *http2fixedBuffer) Read(p []byte) (n int, err error) {
-	if b.r == b.w {
-		return 0, http2errReadEmpty
-	}
-	n = copy(p, b.buf[b.r:b.w])
-	b.r += n
-	if b.r == b.w {
-		b.r = 0
-		b.w = 0
-	}
-	return n, nil
-}
-
-// Len returns the number of bytes of the unread portion of the buffer.
-func (b *http2fixedBuffer) Len() int {
-	return b.w - b.r
-}
-
-// Write copies bytes from p into the buffer.
-// It is an error to write more data than the buffer can hold.
-func (b *http2fixedBuffer) Write(p []byte) (n int, err error) {
-
-	if b.r > 0 && len(p) > len(b.buf)-b.w {
-		copy(b.buf, b.buf[b.r:b.w])
-		b.w -= b.r
-		b.r = 0
-	}
-
-	n = copy(b.buf[b.w:], p)
-	b.w += n
-	if n < len(p) {
-		err = http2errWriteFull
-	}
-	return n, err
-}
-
 // flow is the flow control window's size.
 type http2flow struct {
 	// n is the number of DATA bytes we're allowed to send.
@@ -666,7 +1401,7 @@
 // a frameParser parses a frame given its FrameHeader and payload
 // bytes. The length of payload will always equal fh.Length (which
 // might be 0).
-type http2frameParser func(fh http2FrameHeader, payload []byte) (http2Frame, error)
+type http2frameParser func(fc *http2frameCache, fh http2FrameHeader, payload []byte) (http2Frame, error)
 
 var http2frameParsers = map[http2FrameType]http2frameParser{
 	http2FrameData:         http2parseDataFrame,
@@ -855,25 +1590,33 @@
 	// If the limit is hit, MetaHeadersFrame.Truncated is set true.
 	MaxHeaderListSize uint32
 
+	// TODO: track which type of frame & with which flags was sent
+	// last. Then return an error (unless AllowIllegalWrites) if
+	// we're in the middle of a header block and a
+	// non-Continuation or Continuation on a different stream is
+	// attempted to be written.
+
 	logReads, logWrites bool
 
 	debugFramer       *http2Framer // only use for logging written writes
 	debugFramerBuf    *bytes.Buffer
 	debugReadLoggerf  func(string, ...interface{})
 	debugWriteLoggerf func(string, ...interface{})
+
+	frameCache *http2frameCache // nil if frames aren't reused (default)
 }
 
 func (fr *http2Framer) maxHeaderListSize() uint32 {
 	if fr.MaxHeaderListSize == 0 {
-		return 16 << 20
+		return 16 << 20 // sane default, per docs
 	}
 	return fr.MaxHeaderListSize
 }
 
 func (f *http2Framer) startWrite(ftype http2FrameType, flags http2Flags, streamID uint32) {
-
+	// Write the FrameHeader.
 	f.wbuf = append(f.wbuf[:0],
-		0,
+		0, // 3 bytes of length, filled in in endWrite
 		0,
 		0,
 		byte(ftype),
@@ -885,7 +1628,8 @@
 }
 
 func (f *http2Framer) endWrite() error {
-
+	// Now that we know the final size, fill in the FrameHeader in
+	// the space previously reserved for it. Abuse append.
 	length := len(f.wbuf) - http2frameHeaderLen
 	if length >= (1 << 24) {
 		return http2ErrFrameTooLarge
@@ -909,8 +1653,9 @@
 	if f.debugFramer == nil {
 		f.debugFramerBuf = new(bytes.Buffer)
 		f.debugFramer = http2NewFramer(nil, f.debugFramerBuf)
-		f.debugFramer.logReads = false
-
+		f.debugFramer.logReads = false // we log it ourselves, saying "wrote" below
+		// Let us read anything, even if we accidentally wrote it
+		// in the wrong order:
 		f.debugFramer.AllowIllegalReads = true
 	}
 	f.debugFramerBuf.Write(f.wbuf)
@@ -937,6 +1682,27 @@
 	http2maxFrameSize    = 1<<24 - 1
 )
 
+// SetReuseFrames allows the Framer to reuse Frames.
+// If called on a Framer, Frames returned by calls to ReadFrame are only
+// valid until the next call to ReadFrame.
+func (fr *http2Framer) SetReuseFrames() {
+	if fr.frameCache != nil {
+		return
+	}
+	fr.frameCache = &http2frameCache{}
+}
+
+type http2frameCache struct {
+	dataFrame http2DataFrame
+}
+
+func (fc *http2frameCache) getDataFrame() *http2DataFrame {
+	if fc == nil {
+		return &http2DataFrame{}
+	}
+	return &fc.dataFrame
+}
+
 // NewFramer returns a Framer that writes frames to w and reads them from r.
 func http2NewFramer(w io.Writer, r io.Reader) *http2Framer {
 	fr := &http2Framer{
@@ -1016,7 +1782,7 @@
 	if _, err := io.ReadFull(fr.r, payload); err != nil {
 		return nil, err
 	}
-	f, err := http2typeFrameParser(fh.Type)(fh, payload)
+	f, err := http2typeFrameParser(fh.Type)(fr.frameCache, fh, payload)
 	if err != nil {
 		if ce, ok := err.(http2connError); ok {
 			return nil, fr.connError(ce.Code, ce.Reason)
@@ -1104,14 +1870,18 @@
 	return f.data
 }
 
-func http2parseDataFrame(fh http2FrameHeader, payload []byte) (http2Frame, error) {
+func http2parseDataFrame(fc *http2frameCache, fh http2FrameHeader, payload []byte) (http2Frame, error) {
 	if fh.StreamID == 0 {
-
+		// DATA frames MUST be associated with a stream. If a
+		// DATA frame is received whose stream identifier
+		// field is 0x0, the recipient MUST respond with a
+		// connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR.
 		return nil, http2connError{http2ErrCodeProtocol, "DATA frame with stream ID 0"}
 	}
-	f := &http2DataFrame{
-		http2FrameHeader: fh,
-	}
+	f := fc.getDataFrame()
+	f.http2FrameHeader = fh
+
 	var padSize byte
 	if fh.Flags.Has(http2FlagDataPadded) {
 		var err error
@@ -1121,7 +1891,10 @@
 		}
 	}
 	if int(padSize) > len(payload) {
-
+		// If the length of the padding is greater than the
+		// length of the frame payload, the recipient MUST
+		// treat this as a connection error.
+		// Filed: https://github.com/http2/http2-spec/issues/610
 		return nil, http2connError{http2ErrCodeProtocol, "pad size larger than data payload"}
 	}
 	f.data = payload[:len(payload)-int(padSize)]
@@ -1132,6 +1905,7 @@
 	http2errStreamID    = errors.New("invalid stream ID")
 	http2errDepStreamID = errors.New("invalid dependent stream ID")
 	http2errPadLength   = errors.New("pad length too large")
+	http2errPadBytes    = errors.New("padding bytes must all be zeros unless AllowIllegalWrites is enabled")
 )
 
 func http2validStreamIDOrZero(streamID uint32) bool {
@@ -1155,6 +1929,7 @@
 //
 // If pad is nil, the padding bit is not sent.
 // The length of pad must not exceed 255 bytes.
+// The bytes of pad must all be zero, unless f.AllowIllegalWrites is set.
 //
 // It will perform exactly one Write to the underlying Writer.
 // It is the caller's responsibility not to violate the maximum frame size
@@ -1163,8 +1938,18 @@
 	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
 		return http2errStreamID
 	}
-	if len(pad) > 255 {
-		return http2errPadLength
+	if len(pad) > 0 {
+		if len(pad) > 255 {
+			return http2errPadLength
+		}
+		if !f.AllowIllegalWrites {
+			for _, b := range pad {
+				if b != 0 {
+					// "Padding octets MUST be set to zero when sending."
+					return http2errPadBytes
+				}
+			}
+		}
 	}
 	var flags http2Flags
 	if endStream {
@@ -1192,22 +1977,35 @@
 	p []byte
 }
 
-func http2parseSettingsFrame(fh http2FrameHeader, p []byte) (http2Frame, error) {
+func http2parseSettingsFrame(_ *http2frameCache, fh http2FrameHeader, p []byte) (http2Frame, error) {
 	if fh.Flags.Has(http2FlagSettingsAck) && fh.Length > 0 {
-
+		// When this (ACK 0x1) bit is set, the payload of the
+		// SETTINGS frame MUST be empty. Receipt of a
+		// SETTINGS frame with the ACK flag set and a length
+		// field value other than 0 MUST be treated as a
+		// connection error (Section 5.4.1) of type
+		// FRAME_SIZE_ERROR.
 		return nil, http2ConnectionError(http2ErrCodeFrameSize)
 	}
 	if fh.StreamID != 0 {
-
+		// SETTINGS frames always apply to a connection,
+		// never a single stream. The stream identifier for a
+		// SETTINGS frame MUST be zero (0x0).  If an endpoint
+		// receives a SETTINGS frame whose stream identifier
+		// field is anything other than 0x0, the endpoint MUST
+		// respond with a connection error (Section 5.4.1) of
+		// type PROTOCOL_ERROR.
 		return nil, http2ConnectionError(http2ErrCodeProtocol)
 	}
 	if len(p)%6 != 0 {
-
+		// Expecting even number of 6 byte settings.
 		return nil, http2ConnectionError(http2ErrCodeFrameSize)
 	}
 	f := &http2SettingsFrame{http2FrameHeader: fh, p: p}
 	if v, ok := f.Value(http2SettingInitialWindowSize); ok && v > (1<<31)-1 {
-
+		// Values above the maximum flow control window size of 2^31 - 1 MUST
+		// be treated as a connection error (Section 5.4.1) of type
+		// FLOW_CONTROL_ERROR.
 		return nil, http2ConnectionError(http2ErrCodeFlowControl)
 	}
 	return f, nil
@@ -1281,7 +2079,7 @@
 
 func (f *http2PingFrame) IsAck() bool { return f.Flags.Has(http2FlagPingAck) }
 
-func http2parsePingFrame(fh http2FrameHeader, payload []byte) (http2Frame, error) {
+func http2parsePingFrame(_ *http2frameCache, fh http2FrameHeader, payload []byte) (http2Frame, error) {
 	if len(payload) != 8 {
 		return nil, http2ConnectionError(http2ErrCodeFrameSize)
 	}
@@ -1321,7 +2119,7 @@
 	return f.debugData
 }
 
-func http2parseGoAwayFrame(fh http2FrameHeader, p []byte) (http2Frame, error) {
+func http2parseGoAwayFrame(_ *http2frameCache, fh http2FrameHeader, p []byte) (http2Frame, error) {
 	if fh.StreamID != 0 {
 		return nil, http2ConnectionError(http2ErrCodeProtocol)
 	}
@@ -1361,7 +2159,7 @@
 	return f.p
 }
 
-func http2parseUnknownFrame(fh http2FrameHeader, p []byte) (http2Frame, error) {
+func http2parseUnknownFrame(_ *http2frameCache, fh http2FrameHeader, p []byte) (http2Frame, error) {
 	return &http2UnknownFrame{fh, p}, nil
 }
 
@@ -1372,13 +2170,18 @@
 	Increment uint32 // never read with high bit set
 }
 
-func http2parseWindowUpdateFrame(fh http2FrameHeader, p []byte) (http2Frame, error) {
+func http2parseWindowUpdateFrame(_ *http2frameCache, fh http2FrameHeader, p []byte) (http2Frame, error) {
 	if len(p) != 4 {
 		return nil, http2ConnectionError(http2ErrCodeFrameSize)
 	}
-	inc := binary.BigEndian.Uint32(p[:4]) & 0x7fffffff
+	inc := binary.BigEndian.Uint32(p[:4]) & 0x7fffffff // mask off high reserved bit
 	if inc == 0 {
-
+		// A receiver MUST treat the receipt of a
+		// WINDOW_UPDATE frame with an flow control window
+		// increment of 0 as a stream error (Section 5.4.2) of
+		// type PROTOCOL_ERROR; errors on the connection flow
+		// control window MUST be treated as a connection
+		// error (Section 5.4.1).
 		if fh.StreamID == 0 {
 			return nil, http2ConnectionError(http2ErrCodeProtocol)
 		}
@@ -1395,7 +2198,7 @@
 // If the Stream ID is zero, the window update applies to the
 // connection as a whole.
 func (f *http2Framer) WriteWindowUpdate(streamID, incr uint32) error {
-
+	// "The legal range for the increment to the flow control window is 1 to 2^31-1 (2,147,483,647) octets."
 	if (incr < 1 || incr > 2147483647) && !f.AllowIllegalWrites {
 		return errors.New("illegal window increment value")
 	}
@@ -1432,12 +2235,15 @@
 	return f.http2FrameHeader.Flags.Has(http2FlagHeadersPriority)
 }
 
-func http2parseHeadersFrame(fh http2FrameHeader, p []byte) (_ http2Frame, err error) {
+func http2parseHeadersFrame(_ *http2frameCache, fh http2FrameHeader, p []byte) (_ http2Frame, err error) {
 	hf := &http2HeadersFrame{
 		http2FrameHeader: fh,
 	}
 	if fh.StreamID == 0 {
-
+		// HEADERS frames MUST be associated with a stream. If a HEADERS frame
+		// is received whose stream identifier field is 0x0, the recipient MUST
+		// respond with a connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR.
 		return nil, http2connError{http2ErrCodeProtocol, "HEADERS frame with stream ID 0"}
 	}
 	var padLength uint8
@@ -1453,7 +2259,7 @@
 			return nil, err
 		}
 		hf.Priority.StreamDep = v & 0x7fffffff
-		hf.Priority.Exclusive = (v != hf.Priority.StreamDep)
+		hf.Priority.Exclusive = (v != hf.Priority.StreamDep) // high bit was set
 		p, hf.Priority.Weight, err = http2readByte(p)
 		if err != nil {
 			return nil, err
@@ -1556,7 +2362,7 @@
 	Exclusive bool
 
 	// Weight is the stream's zero-indexed weight. It should be
-	// set together with StreamDep, or neither should be set.  Per
+	// set together with StreamDep, or neither should be set. Per
 	// the spec, "Add one to the value to obtain a weight between
 	// 1 and 256."
 	Weight uint8
@@ -1566,7 +2372,7 @@
 	return p == http2PriorityParam{}
 }
 
-func http2parsePriorityFrame(fh http2FrameHeader, payload []byte) (http2Frame, error) {
+func http2parsePriorityFrame(_ *http2frameCache, fh http2FrameHeader, payload []byte) (http2Frame, error) {
 	if fh.StreamID == 0 {
 		return nil, http2connError{http2ErrCodeProtocol, "PRIORITY frame with stream ID 0"}
 	}
@@ -1574,13 +2380,13 @@
 		return nil, http2connError{http2ErrCodeFrameSize, fmt.Sprintf("PRIORITY frame payload size was %d; want 5", len(payload))}
 	}
 	v := binary.BigEndian.Uint32(payload[:4])
-	streamID := v & 0x7fffffff
+	streamID := v & 0x7fffffff // mask off high bit
 	return &http2PriorityFrame{
 		http2FrameHeader: fh,
 		http2PriorityParam: http2PriorityParam{
 			Weight:    payload[4],
 			StreamDep: streamID,
-			Exclusive: streamID != v,
+			Exclusive: streamID != v, // was high bit set?
 		},
 	}, nil
 }
@@ -1613,7 +2419,7 @@
 	ErrCode http2ErrCode
 }
 
-func http2parseRSTStreamFrame(fh http2FrameHeader, p []byte) (http2Frame, error) {
+func http2parseRSTStreamFrame(_ *http2frameCache, fh http2FrameHeader, p []byte) (http2Frame, error) {
 	if len(p) != 4 {
 		return nil, http2ConnectionError(http2ErrCodeFrameSize)
 	}
@@ -1643,7 +2449,7 @@
 	headerFragBuf []byte
 }
 
-func http2parseContinuationFrame(fh http2FrameHeader, p []byte) (http2Frame, error) {
+func http2parseContinuationFrame(_ *http2frameCache, fh http2FrameHeader, p []byte) (http2Frame, error) {
 	if fh.StreamID == 0 {
 		return nil, http2connError{http2ErrCodeProtocol, "CONTINUATION frame with stream ID 0"}
 	}
@@ -1693,12 +2499,17 @@
 	return f.http2FrameHeader.Flags.Has(http2FlagPushPromiseEndHeaders)
 }
 
-func http2parsePushPromise(fh http2FrameHeader, p []byte) (_ http2Frame, err error) {
+func http2parsePushPromise(_ *http2frameCache, fh http2FrameHeader, p []byte) (_ http2Frame, err error) {
 	pp := &http2PushPromiseFrame{
 		http2FrameHeader: fh,
 	}
 	if pp.StreamID == 0 {
-
+		// PUSH_PROMISE frames MUST be associated with an existing,
+		// peer-initiated stream. The stream identifier of a
+		// PUSH_PROMISE frame indicates the stream it is associated
+		// with. If the stream identifier field specifies the value
+		// 0x0, a recipient MUST respond with a connection error
+		// (Section 5.4.1) of type PROTOCOL_ERROR.
 		return nil, http2ConnectionError(http2ErrCodeProtocol)
 	}
 	// The PUSH_PROMISE frame includes optional padding.
@@ -1717,7 +2528,7 @@
 	pp.PromiseID = pp.PromiseID & (1<<31 - 1)
 
 	if int(padLength) > len(p) {
-
+		// like the DATA frame, error out if padding is longer than the body.
 		return nil, http2ConnectionError(http2ErrCodeProtocol)
 	}
 	pp.headerFragBuf = p[:len(p)-int(padLength)]
@@ -1887,7 +2698,9 @@
 		default:
 			return http2pseudoHeaderError(hf.Name)
 		}
-
+		// Check for duplicates.
+		// This would be a bad algorithm, but N is 4.
+		// And this doesn't allocate.
 		for _, hf2 := range pf[:i] {
 			if hf.Name == hf2.Name {
 				return http2duplicatePseudoHeaderError(hf.Name)
@@ -1905,7 +2718,8 @@
 	if uint32(int(v)) == v {
 		return int(v)
 	}
-
+	// They had a crazy big number for MaxHeaderBytes anyway,
+	// so give them unlimited header lengths:
 	return 0
 }
 
@@ -1960,7 +2774,7 @@
 
 		mh.Fields = append(mh.Fields, hf)
 	})
-
+	// Lose reference to MetaHeadersFrame:
 	defer hdec.SetEmitFunc(func(hf hpack.HeaderField) {})
 
 	var hc http2headersOrContinuation = hf
@@ -1976,7 +2790,7 @@
 		if f, err := fr.ReadFrame(); err != nil {
 			return nil, err
 		} else {
-			hc = f.(*http2ContinuationFrame)
+			hc = f.(*http2ContinuationFrame) // guaranteed by checkFrameOrder
 		}
 	}
 
@@ -2018,7 +2832,7 @@
 			return nil
 		})
 		if n > 0 {
-			buf.Truncate(buf.Len() - 1)
+			buf.Truncate(buf.Len() - 1) // remove trailing comma
 		}
 	case *http2DataFrame:
 		data := f.Data()
@@ -2050,29 +2864,6 @@
 	return t1.ExpectContinueTimeout
 }
 
-// isBadCipher reports whether the cipher is blacklisted by the HTTP/2 spec.
-func http2isBadCipher(cipher uint16) bool {
-	switch cipher {
-	case tls.TLS_RSA_WITH_RC4_128_SHA,
-		tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA,
-		tls.TLS_RSA_WITH_AES_128_CBC_SHA,
-		tls.TLS_RSA_WITH_AES_256_CBC_SHA,
-		tls.TLS_RSA_WITH_AES_128_GCM_SHA256,
-		tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
-		tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
-		tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
-		tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
-		tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA,
-		tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
-		tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
-		tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA:
-
-		return true
-	default:
-		return false
-	}
-}
-
 type http2contextContext interface {
 	context.Context
 }
@@ -2164,7 +2955,11 @@
 	return cc.ping(ctx)
 }
 
-func http2cloneTLSConfig(c *tls.Config) *tls.Config { return c.Clone() }
+func http2cloneTLSConfig(c *tls.Config) *tls.Config {
+	c2 := c.Clone()
+	c2.GetClientCertificate = c.GetClientCertificate // golang.org/issue/19264
+	return c2
+}
 
 var _ Pusher = (*http2responseWriter)(nil)
 
@@ -2201,6 +2996,13 @@
 	return body == NoBody
 }
 
+func http2go18httpNoBody() io.ReadCloser { return NoBody } // for tests only
+
+func http2configureServer19(s *Server, conf *http2Server) error {
+	s.RegisterOnShutdown(conf.state.startGracefulShutdown)
+	return nil
+}
+
 var http2DebugGoroutines = os.Getenv("DEBUG_HTTP2_GOROUTINES") == "1"
 
 type http2goroutineLock uint64
@@ -2237,7 +3039,7 @@
 	defer http2littleBuf.Put(bp)
 	b := *bp
 	b = b[:runtime.Stack(b, false)]
-
+	// Parse the 4707 out of "goroutine 4707 ["
 	b = bytes.TrimPrefix(b, http2goroutineSpace)
 	i := bytes.IndexByte(b, ' ')
 	if i < 0 {
@@ -2273,9 +3075,10 @@
 		goto Error
 
 	case 2 <= base && base <= 36:
+		// valid base; nothing to do
 
 	case base == 0:
-
+		// Look for octal, hex prefix.
 		switch {
 		case s[0] == '0' && len(s) > 1 && (s[1] == 'x' || s[1] == 'X'):
 			base = 16
@@ -2321,7 +3124,7 @@
 		}
 
 		if n >= cutoff {
-
+			// n*base overflows
 			n = 1<<64 - 1
 			err = strconv.ErrRange
 			goto Error
@@ -2330,7 +3133,7 @@
 
 		n1 := n + uint64(v)
 		if n1 < n || n1 > maxVal {
-
+			// n+v overflows
 			n = 1<<64 - 1
 			err = strconv.ErrRange
 			goto Error
@@ -2514,7 +3317,7 @@
 
 // Valid reports whether the setting is valid.
 func (s http2Setting) Valid() error {
-
+	// Limits and error codes from 6.5.2 Defined SETTINGS Parameters
 	switch s.ID {
 	case http2SettingEnablePush:
 		if s.Val != 1 && s.Val != 0 {
@@ -2758,7 +3561,8 @@
 }
 
 func (s *http2sorter) SortStrings(ss []string) {
-
+	// Our sorter works on s.v, which sorter owns, so
+	// stash it away while we sort the user's buffer.
 	save := s.v
 	s.v = ss
 	sort.Sort(s)
@@ -2768,27 +3572,31 @@
 // validPseudoPath reports whether v is a valid :path pseudo-header
 // value. It must be either:
 //
-//     *) a non-empty string starting with '/', but not with with "//",
+//     *) a non-empty string starting with '/'
 //     *) the string '*', for OPTIONS requests.
 //
 // For now this is only used a quick check for deciding when to clean
 // up Opaque URLs before sending requests from the Transport.
 // See golang.org/issue/16847
+//
+// We used to enforce that the path also didn't start with "//", but
+// Google's GFE accepts such paths and Chrome sends them, so ignore
+// that part of the spec. See golang.org/issue/19103.
 func http2validPseudoPath(v string) bool {
-	return (len(v) > 0 && v[0] == '/' && (len(v) == 1 || v[1] != '/')) || v == "*"
+	return (len(v) > 0 && v[0] == '/') || v == "*"
 }
 
-// pipe is a goroutine-safe io.Reader/io.Writer pair.  It's like
+// pipe is a goroutine-safe io.Reader/io.Writer pair. It's like
 // io.Pipe except there are no PipeReader/PipeWriter halves, and the
 // underlying buffer is an interface. (io.Pipe is always unbuffered)
 type http2pipe struct {
 	mu       sync.Mutex
-	c        sync.Cond // c.L lazily initialized to &p.mu
-	b        http2pipeBuffer
-	err      error         // read error once empty. non-nil means closed.
-	breakErr error         // immediate read error (caller doesn't see rest of b)
-	donec    chan struct{} // closed on error
-	readFn   func()        // optional code to run in Read before error
+	c        sync.Cond       // c.L lazily initialized to &p.mu
+	b        http2pipeBuffer // nil when done reading
+	err      error           // read error once empty. non-nil means closed.
+	breakErr error           // immediate read error (caller doesn't see rest of b)
+	donec    chan struct{}   // closed on error
+	readFn   func()          // optional code to run in Read before error
 }
 
 type http2pipeBuffer interface {
@@ -2800,6 +3608,9 @@
 func (p *http2pipe) Len() int {
 	p.mu.Lock()
 	defer p.mu.Unlock()
+	if p.b == nil {
+		return 0
+	}
 	return p.b.Len()
 }
 
@@ -2815,14 +3626,15 @@
 		if p.breakErr != nil {
 			return 0, p.breakErr
 		}
-		if p.b.Len() > 0 {
+		if p.b != nil && p.b.Len() > 0 {
 			return p.b.Read(d)
 		}
 		if p.err != nil {
 			if p.readFn != nil {
-				p.readFn()
-				p.readFn = nil
+				p.readFn()     // e.g. copy trailers
+				p.readFn = nil // not sticky like p.err
 			}
+			p.b = nil
 			return 0, p.err
 		}
 		p.c.Wait()
@@ -2843,6 +3655,9 @@
 	if p.err != nil {
 		return 0, http2errClosedPipeWrite
 	}
+	if p.breakErr != nil {
+		return len(d), nil // discard when there is no reader
+	}
 	return p.b.Write(d)
 }
 
@@ -2873,10 +3688,13 @@
 	}
 	defer p.c.Signal()
 	if *dst != nil {
-
+		// Already been done.
 		return
 	}
 	p.readFn = fn
+	if dst == &p.breakErr {
+		p.b = nil
+	}
 	*dst = err
 	p.closeDoneLocked()
 }
@@ -2886,7 +3704,8 @@
 	if p.donec == nil {
 		return
 	}
-
+	// Close if unclosed. This isn't racy since we always
+	// hold p.mu while closing.
 	select {
 	case <-p.donec:
 	default:
@@ -2912,7 +3731,7 @@
 	if p.donec == nil {
 		p.donec = make(chan struct{})
 		if p.err != nil || p.breakErr != nil {
-
+			// Already hit an error.
 			p.closeDoneLocked()
 		}
 	}
@@ -2980,9 +3799,41 @@
 	// activity for the purposes of IdleTimeout.
 	IdleTimeout time.Duration
 
+	// MaxUploadBufferPerConnection is the size of the initial flow
+	// control window for each connections. The HTTP/2 spec does not
+	// allow this to be smaller than 65535 or larger than 2^32-1.
+	// If the value is outside this range, a default value will be
+	// used instead.
+	MaxUploadBufferPerConnection int32
+
+	// MaxUploadBufferPerStream is the size of the initial flow control
+	// window for each stream. The HTTP/2 spec does not allow this to
+	// be larger than 2^32-1. If the value is zero or larger than the
+	// maximum, a default value will be used instead.
+	MaxUploadBufferPerStream int32
+
 	// NewWriteScheduler constructs a write scheduler for a connection.
 	// If nil, a default scheduler is chosen.
 	NewWriteScheduler func() http2WriteScheduler
+
+	// Internal state. This is a pointer (rather than embedded directly)
+	// so that we don't embed a Mutex in this struct, which will make the
+	// struct non-copyable, which might break some callers.
+	state *http2serverInternalState
+}
+
+func (s *http2Server) initialConnRecvWindowSize() int32 {
+	if s.MaxUploadBufferPerConnection > http2initialWindowSize {
+		return s.MaxUploadBufferPerConnection
+	}
+	return 1 << 20
+}
+
+func (s *http2Server) initialStreamRecvWindowSize() int32 {
+	if s.MaxUploadBufferPerStream > 0 {
+		return s.MaxUploadBufferPerStream
+	}
+	return 1 << 20
 }
 
 func (s *http2Server) maxReadFrameSize() uint32 {
@@ -2999,6 +3850,40 @@
 	return http2defaultMaxStreams
 }
 
+type http2serverInternalState struct {
+	mu          sync.Mutex
+	activeConns map[*http2serverConn]struct{}
+}
+
+func (s *http2serverInternalState) registerConn(sc *http2serverConn) {
+	if s == nil {
+		return // if the Server was used without calling ConfigureServer
+	}
+	s.mu.Lock()
+	s.activeConns[sc] = struct{}{}
+	s.mu.Unlock()
+}
+
+func (s *http2serverInternalState) unregisterConn(sc *http2serverConn) {
+	if s == nil {
+		return // if the Server was used without calling ConfigureServer
+	}
+	s.mu.Lock()
+	delete(s.activeConns, sc)
+	s.mu.Unlock()
+}
+
+func (s *http2serverInternalState) startGracefulShutdown() {
+	if s == nil {
+		return // if the Server was used without calling ConfigureServer
+	}
+	s.mu.Lock()
+	for sc := range s.activeConns {
+		sc.startGracefulShutdown()
+	}
+	s.mu.Unlock()
+}
+
 // ConfigureServer adds HTTP/2 support to a net/http Server.
 //
 // The configuration conf may be nil.
@@ -3011,9 +3896,13 @@
 	if conf == nil {
 		conf = new(http2Server)
 	}
+	conf.state = &http2serverInternalState{activeConns: make(map[*http2serverConn]struct{})}
 	if err := http2configureServer18(s, conf); err != nil {
 		return err
 	}
+	if err := http2configureServer19(s, conf); err != nil {
+		return err
+	}
 
 	if s.TLSConfig == nil {
 		s.TLSConfig = new(tls.Config)
@@ -3039,6 +3928,13 @@
 		}
 	}
 
+	// Note: not setting MinVersion to tls.VersionTLS12,
+	// as we don't want to interfere with HTTP/1.1 traffic
+	// on the user's server. We enforce TLS 1.2 later once
+	// we accept a connection. Ideally this should be done
+	// during next-proto selection, but using TLS <1.2 with
+	// HTTP/2 is still the client's bug.
+
 	s.TLSConfig.PreferServerCipherSuites = true
 
 	haveNPN := false
@@ -3118,29 +4014,37 @@
 	defer cancel()
 
 	sc := &http2serverConn{
-		srv:               s,
-		hs:                opts.baseConfig(),
-		conn:              c,
-		baseCtx:           baseCtx,
-		remoteAddrStr:     c.RemoteAddr().String(),
-		bw:                http2newBufferedWriter(c),
-		handler:           opts.handler(),
-		streams:           make(map[uint32]*http2stream),
-		readFrameCh:       make(chan http2readFrameResult),
-		wantWriteFrameCh:  make(chan http2FrameWriteRequest, 8),
-		wantStartPushCh:   make(chan http2startPushRequest, 8),
-		wroteFrameCh:      make(chan http2frameWriteResult, 1),
-		bodyReadCh:        make(chan http2bodyReadMsg),
-		doneServing:       make(chan struct{}),
-		clientMaxStreams:  math.MaxUint32,
-		advMaxStreams:     s.maxConcurrentStreams(),
-		initialWindowSize: http2initialWindowSize,
-		maxFrameSize:      http2initialMaxFrameSize,
-		headerTableSize:   http2initialHeaderTableSize,
-		serveG:            http2newGoroutineLock(),
-		pushEnabled:       true,
+		srv:                         s,
+		hs:                          opts.baseConfig(),
+		conn:                        c,
+		baseCtx:                     baseCtx,
+		remoteAddrStr:               c.RemoteAddr().String(),
+		bw:                          http2newBufferedWriter(c),
+		handler:                     opts.handler(),
+		streams:                     make(map[uint32]*http2stream),
+		readFrameCh:                 make(chan http2readFrameResult),
+		wantWriteFrameCh:            make(chan http2FrameWriteRequest, 8),
+		serveMsgCh:                  make(chan interface{}, 8),
+		wroteFrameCh:                make(chan http2frameWriteResult, 1), // buffered; one send in writeFrameAsync
+		bodyReadCh:                  make(chan http2bodyReadMsg),         // buffering doesn't matter either way
+		doneServing:                 make(chan struct{}),
+		clientMaxStreams:            math.MaxUint32, // Section 6.5.2: "Initially, there is no limit to this value"
+		advMaxStreams:               s.maxConcurrentStreams(),
+		initialStreamSendWindowSize: http2initialWindowSize,
+		maxFrameSize:                http2initialMaxFrameSize,
+		headerTableSize:             http2initialHeaderTableSize,
+		serveG:                      http2newGoroutineLock(),
+		pushEnabled:                 true,
 	}
 
+	s.state.registerConn(sc)
+	defer s.state.unregisterConn(sc)
+
+	// The net/http package sets the write deadline from the
+	// http.Server.WriteTimeout during the TLS handshake, but then
+	// passes the connection off to us with the deadline already set.
+	// Write deadlines are set per stream in serverConn.newStream.
+	// Disarm the net.Conn write deadline here.
 	if sc.hs.WriteTimeout != 0 {
 		sc.conn.SetWriteDeadline(time.Time{})
 	}
@@ -3151,6 +4055,9 @@
 		sc.writeSched = http2NewRandomWriteScheduler()
 	}
 
+	// These start at the RFC-specified defaults. If there is a higher
+	// configured value for inflow, that will be updated when we send a
+	// WINDOW_UPDATE shortly after sending SETTINGS.
 	sc.flow.add(http2initialWindowSize)
 	sc.inflow.add(http2initialWindowSize)
 	sc.hpackEncoder = hpack.NewEncoder(&sc.headerWriteBuf)
@@ -3164,18 +4071,44 @@
 	if tc, ok := c.(http2connectionStater); ok {
 		sc.tlsState = new(tls.ConnectionState)
 		*sc.tlsState = tc.ConnectionState()
-
+		// 9.2 Use of TLS Features
+		// An implementation of HTTP/2 over TLS MUST use TLS
+		// 1.2 or higher with the restrictions on feature set
+		// and cipher suite described in this section. Due to
+		// implementation limitations, it might not be
+		// possible to fail TLS negotiation. An endpoint MUST
+		// immediately terminate an HTTP/2 connection that
+		// does not meet the TLS requirements described in
+		// this section with a connection error (Section
+		// 5.4.1) of type INADEQUATE_SECURITY.
 		if sc.tlsState.Version < tls.VersionTLS12 {
 			sc.rejectConn(http2ErrCodeInadequateSecurity, "TLS version too low")
 			return
 		}
 
 		if sc.tlsState.ServerName == "" {
-
+			// Client must use SNI, but we don't enforce that anymore,
+			// since it was causing problems when connecting to bare IP
+			// addresses during development.
+			//
+			// TODO: optionally enforce? Or enforce at the time we receive
+			// a new request, and verify the the ServerName matches the :authority?
+			// But that precludes proxy situations, perhaps.
+			//
+			// So for now, do nothing here again.
 		}
 
 		if !s.PermitProhibitedCipherSuites && http2isBadCipher(sc.tlsState.CipherSuite) {
-
+			// "Endpoints MAY choose to generate a connection error
+			// (Section 5.4.1) of type INADEQUATE_SECURITY if one of
+			// the prohibited cipher suites are negotiated."
+			//
+			// We choose that. In my opinion, the spec is weak
+			// here. It also says both parties must support at least
+			// TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 so there's no
+			// excuses here. If we really must, we could allow an
+			// "AllowInsecureWeakCiphers" option on the server later.
+			// Let's see how it plays out first.
 			sc.rejectConn(http2ErrCodeInadequateSecurity, fmt.Sprintf("Prohibited TLS 1.2 Cipher Suite: %x", sc.tlsState.CipherSuite))
 			return
 		}
@@ -3189,7 +4122,7 @@
 
 func (sc *http2serverConn) rejectConn(err http2ErrCode, debug string) {
 	sc.vlogf("http2: server rejecting conn: %v, %s", err, debug)
-
+	// ignoring errors. hanging up anyway.
 	sc.framer.WriteGoAway(0, err, []byte(debug))
 	sc.bw.Flush()
 	sc.conn.Close()
@@ -3207,10 +4140,9 @@
 	doneServing      chan struct{}               // closed when serverConn.serve ends
 	readFrameCh      chan http2readFrameResult   // written by serverConn.readFrames
 	wantWriteFrameCh chan http2FrameWriteRequest // from handlers -> serve
-	wantStartPushCh  chan http2startPushRequest  // from handlers -> serve
 	wroteFrameCh     chan http2frameWriteResult  // from writeFrameAsync -> serve, tickles more frame writes
 	bodyReadCh       chan http2bodyReadMsg       // from handlers -> serve
-	testHookCh       chan func(int)              // code to run on the serve loop
+	serveMsgCh       chan interface{}            // misc messages & code to send to / run on the serve loop
 	flow             http2flow                   // conn-wide (not stream-specific) outbound flow control
 	inflow           http2flow                   // conn-wide inbound flow control
 	tlsState         *tls.ConnectionState        // shared by all handlers, like net/http
@@ -3218,38 +4150,39 @@
 	writeSched       http2WriteScheduler
 
 	// Everything following is owned by the serve loop; use serveG.check():
-	serveG                http2goroutineLock // used to verify funcs are on serve()
-	pushEnabled           bool
-	sawFirstSettings      bool // got the initial SETTINGS frame after the preface
-	needToSendSettingsAck bool
-	unackedSettings       int    // how many SETTINGS have we sent without ACKs?
-	clientMaxStreams      uint32 // SETTINGS_MAX_CONCURRENT_STREAMS from client (our PUSH_PROMISE limit)
-	advMaxStreams         uint32 // our SETTINGS_MAX_CONCURRENT_STREAMS advertised the client
-	curClientStreams      uint32 // number of open streams initiated by the client
-	curPushedStreams      uint32 // number of open streams initiated by server push
-	maxClientStreamID     uint32 // max ever seen from client (odd), or 0 if there have been no client requests
-	maxPushPromiseID      uint32 // ID of the last push promise (even), or 0 if there have been no pushes
-	streams               map[uint32]*http2stream
-	initialWindowSize     int32
-	maxFrameSize          int32
-	headerTableSize       uint32
-	peerMaxHeaderListSize uint32            // zero means unknown (default)
-	canonHeader           map[string]string // http2-lower-case -> Go-Canonical-Case
-	writingFrame          bool              // started writing a frame (on serve goroutine or separate)
-	writingFrameAsync     bool              // started a frame on its own goroutine but haven't heard back on wroteFrameCh
-	needsFrameFlush       bool              // last frame write wasn't a flush
-	inGoAway              bool              // we've started to or sent GOAWAY
-	inFrameScheduleLoop   bool              // whether we're in the scheduleFrameWrite loop
-	needToSendGoAway      bool              // we need to schedule a GOAWAY frame write
-	goAwayCode            http2ErrCode
-	shutdownTimerCh       <-chan time.Time // nil until used
-	shutdownTimer         *time.Timer      // nil until used
-	idleTimer             *time.Timer      // nil if unused
-	idleTimerCh           <-chan time.Time // nil if unused
+	serveG                      http2goroutineLock // used to verify funcs are on serve()
+	pushEnabled                 bool
+	sawFirstSettings            bool // got the initial SETTINGS frame after the preface
+	needToSendSettingsAck       bool
+	unackedSettings             int    // how many SETTINGS have we sent without ACKs?
+	clientMaxStreams            uint32 // SETTINGS_MAX_CONCURRENT_STREAMS from client (our PUSH_PROMISE limit)
+	advMaxStreams               uint32 // our SETTINGS_MAX_CONCURRENT_STREAMS advertised the client
+	curClientStreams            uint32 // number of open streams initiated by the client
+	curPushedStreams            uint32 // number of open streams initiated by server push
+	maxClientStreamID           uint32 // max ever seen from client (odd), or 0 if there have been no client requests
+	maxPushPromiseID            uint32 // ID of the last push promise (even), or 0 if there have been no pushes
+	streams                     map[uint32]*http2stream
+	initialStreamSendWindowSize int32
+	maxFrameSize                int32
+	headerTableSize             uint32
+	peerMaxHeaderListSize       uint32            // zero means unknown (default)
+	canonHeader                 map[string]string // http2-lower-case -> Go-Canonical-Case
+	writingFrame                bool              // started writing a frame (on serve goroutine or separate)
+	writingFrameAsync           bool              // started a frame on its own goroutine but haven't heard back on wroteFrameCh
+	needsFrameFlush             bool              // last frame write wasn't a flush
+	inGoAway                    bool              // we've started to or sent GOAWAY
+	inFrameScheduleLoop         bool              // whether we're in the scheduleFrameWrite loop
+	needToSendGoAway            bool              // we need to schedule a GOAWAY frame write
+	goAwayCode                  http2ErrCode
+	shutdownTimer               *time.Timer // nil until used
+	idleTimer                   *time.Timer // nil if unused
 
 	// Owned by the writeFrameAsync goroutine:
 	headerWriteBuf bytes.Buffer
 	hpackEncoder   *hpack.Encoder
+
+	// Used by startGracefulShutdown.
+	shutdownOnce sync.Once
 }
 
 func (sc *http2serverConn) maxHeaderListSize() uint32 {
@@ -3294,10 +4227,10 @@
 	numTrailerValues int64
 	weight           uint8
 	state            http2streamState
-	resetQueued      bool   // RST_STREAM queued for write; set by sc.resetStream
-	gotTrailerHeader bool   // HEADER frame for trailers was seen
-	wroteHeaders     bool   // whether we wrote headers (not status 100)
-	reqBuf           []byte // if non-nil, body pipe buffer to return later at EOF
+	resetQueued      bool        // RST_STREAM queued for write; set by sc.resetStream
+	gotTrailerHeader bool        // HEADER frame for trailers was seen
+	wroteHeaders     bool        // whether we wrote headers (not status 100)
+	writeDeadline    *time.Timer // nil if unused
 
 	trailer    Header // accumulated trailers
 	reqTrailer Header // handler's Request.Trailer
@@ -3315,11 +4248,16 @@
 
 func (sc *http2serverConn) state(streamID uint32) (http2streamState, *http2stream) {
 	sc.serveG.check()
-
+	// http://tools.ietf.org/html/rfc7540#section-5.1
 	if st, ok := sc.streams[streamID]; ok {
 		return st.state, st
 	}
-
+	// "The first use of a new stream identifier implicitly closes all
+	// streams in the "idle" state that might have been initiated by
+	// that peer with a lower-valued stream identifier. For example, if
+	// a client sends a HEADERS frame on stream 7 without ever sending a
+	// frame on stream 5, then stream 5 transitions to the "closed"
+	// state when the first frame for stream 7 is sent or received."
 	if streamID%2 == 1 {
 		if streamID <= sc.maxClientStreamID {
 			return http2stateClosed, nil
@@ -3373,11 +4311,18 @@
 		return false
 	}
 
+	// TODO: remove this string search and be more like the Windows
+	// case below. That might involve modifying the standard library
+	// to return better error types.
 	str := err.Error()
 	if strings.Contains(str, "use of closed network connection") {
 		return true
 	}
 
+	// TODO(bradfitz): x/tools/cmd/bundle doesn't really support
+	// build tags, so I can't make an http2_windows.go file with
+	// Windows-specific stuff. Fix that and move this, once we
+	// have a way to bundle this into std's net/http somehow.
 	if runtime.GOOS == "windows" {
 		if oe, ok := err.(*net.OpError); ok && oe.Op == "read" {
 			if se, ok := oe.Err.(*os.SyscallError); ok && se.Syscall == "wsarecv" {
@@ -3397,7 +4342,7 @@
 		return
 	}
 	if err == io.EOF || err == io.ErrUnexpectedEOF || http2isClosedConnError(err) {
-
+		// Boring, expected errors.
 		sc.vlogf(format, args...)
 	} else {
 		sc.logf(format, args...)
@@ -3487,7 +4432,7 @@
 }
 
 func (sc *http2serverConn) notePanic() {
-
+	// Note: this is for serverConn.serve panicking, not http.Handler code.
 	if http2testHookOnPanicMu != nil {
 		http2testHookOnPanicMu.Lock()
 		defer http2testHookOnPanicMu.Unlock()
@@ -3507,7 +4452,7 @@
 	defer sc.conn.Close()
 	defer sc.closeAllStreamsOnConnClose()
 	defer sc.stopShutdownTimer()
-	defer close(sc.doneServing)
+	defer close(sc.doneServing) // unblocks handlers trying to send
 
 	if http2VerboseLogs {
 		sc.vlogf("http2: server connection from %v on %p", sc.conn.RemoteAddr(), sc.hs)
@@ -3518,44 +4463,48 @@
 			{http2SettingMaxFrameSize, sc.srv.maxReadFrameSize()},
 			{http2SettingMaxConcurrentStreams, sc.advMaxStreams},
 			{http2SettingMaxHeaderListSize, sc.maxHeaderListSize()},
+			{http2SettingInitialWindowSize, uint32(sc.srv.initialStreamRecvWindowSize())},
 		},
 	})
 	sc.unackedSettings++
 
+	// Each connection starts with intialWindowSize inflow tokens.
+	// If a higher value is configured, we add more tokens.
+	if diff := sc.srv.initialConnRecvWindowSize() - http2initialWindowSize; diff > 0 {
+		sc.sendWindowUpdate(nil, int(diff))
+	}
+
 	if err := sc.readPreface(); err != nil {
 		sc.condlogf(err, "http2: server: error reading preface from client %v: %v", sc.conn.RemoteAddr(), err)
 		return
 	}
-
+	// Now that we've got the preface, get us out of the
+	// "StateNew" state. We can't go directly to idle, though.
+	// Active means we read some data and anticipate a request. We'll
+	// do another Active when we get a HEADERS frame.
 	sc.setConnState(StateActive)
 	sc.setConnState(StateIdle)
 
 	if sc.srv.IdleTimeout != 0 {
-		sc.idleTimer = time.NewTimer(sc.srv.IdleTimeout)
+		sc.idleTimer = time.AfterFunc(sc.srv.IdleTimeout, sc.onIdleTimer)
 		defer sc.idleTimer.Stop()
-		sc.idleTimerCh = sc.idleTimer.C
 	}
 
-	var gracefulShutdownCh chan struct{}
-	if sc.hs != nil {
-		ch := http2h1ServerShutdownChan(sc.hs)
-		if ch != nil {
-			gracefulShutdownCh = make(chan struct{})
-			go sc.awaitGracefulShutdown(ch, gracefulShutdownCh)
-		}
-	}
+	go sc.readFrames() // closed by defer sc.conn.Close above
 
-	go sc.readFrames()
+	settingsTimer := time.AfterFunc(http2firstSettingsTimeout, sc.onSettingsTimer)
+	defer settingsTimer.Stop()
 
-	settingsTimer := time.NewTimer(http2firstSettingsTimeout)
 	loopNum := 0
 	for {
 		loopNum++
 		select {
 		case wr := <-sc.wantWriteFrameCh:
+			if se, ok := wr.write.(http2StreamError); ok {
+				sc.resetStream(se)
+				break
+			}
 			sc.writeFrame(wr)
-		case spr := <-sc.wantStartPushCh:
-			sc.startPush(spr)
 		case res := <-sc.wroteFrameCh:
 			sc.wroteFrame(res)
 		case res := <-sc.readFrameCh:
@@ -3563,26 +4512,37 @@
 				return
 			}
 			res.readMore()
-			if settingsTimer.C != nil {
+			if settingsTimer != nil {
 				settingsTimer.Stop()
-				settingsTimer.C = nil
+				settingsTimer = nil
 			}
 		case m := <-sc.bodyReadCh:
 			sc.noteBodyRead(m.st, m.n)
-		case <-settingsTimer.C:
-			sc.logf("timeout waiting for SETTINGS frames from %v", sc.conn.RemoteAddr())
-			return
-		case <-gracefulShutdownCh:
-			gracefulShutdownCh = nil
-			sc.startGracefulShutdown()
-		case <-sc.shutdownTimerCh:
-			sc.vlogf("GOAWAY close timer fired; closing conn from %v", sc.conn.RemoteAddr())
-			return
-		case <-sc.idleTimerCh:
-			sc.vlogf("connection is idle")
-			sc.goAway(http2ErrCodeNo)
-		case fn := <-sc.testHookCh:
-			fn(loopNum)
+		case msg := <-sc.serveMsgCh:
+			switch v := msg.(type) {
+			case func(int):
+				v(loopNum) // for testing
+			case *http2serverMessage:
+				switch v {
+				case http2settingsTimerMsg:
+					sc.logf("timeout waiting for SETTINGS frames from %v", sc.conn.RemoteAddr())
+					return
+				case http2idleTimerMsg:
+					sc.vlogf("connection is idle")
+					sc.goAway(http2ErrCodeNo)
+				case http2shutdownTimerMsg:
+					sc.vlogf("GOAWAY close timer fired; closing conn from %v", sc.conn.RemoteAddr())
+					return
+				case http2gracefulShutdownMsg:
+					sc.startGracefulShutdownInternal()
+				default:
+					panic("unknown timer")
+				}
+			case *http2startPushRequest:
+				sc.startPush(v)
+			default:
+				panic(fmt.Sprintf("unexpected type %T", v))
+			}
 		}
 
 		if sc.inGoAway && sc.curOpenStreams() == 0 && !sc.needToSendGoAway && !sc.writingFrame {
@@ -3599,12 +4559,36 @@
 	}
 }
 
+type http2serverMessage int
+
+// Message values sent to serveMsgCh.
+var (
+	http2settingsTimerMsg    = new(http2serverMessage)
+	http2idleTimerMsg        = new(http2serverMessage)
+	http2shutdownTimerMsg    = new(http2serverMessage)
+	http2gracefulShutdownMsg = new(http2serverMessage)
+)
+
+func (sc *http2serverConn) onSettingsTimer() { sc.sendServeMsg(http2settingsTimerMsg) }
+
+func (sc *http2serverConn) onIdleTimer() { sc.sendServeMsg(http2idleTimerMsg) }
+
+func (sc *http2serverConn) onShutdownTimer() { sc.sendServeMsg(http2shutdownTimerMsg) }
+
+func (sc *http2serverConn) sendServeMsg(msg interface{}) {
+	sc.serveG.checkNotOn() // NOT
+	select {
+	case sc.serveMsgCh <- msg:
+	case <-sc.doneServing:
+	}
+}
+
 // readPreface reads the ClientPreface greeting from the peer
 // or returns an error on timeout or an invalid greeting.
 func (sc *http2serverConn) readPreface() error {
 	errc := make(chan error, 1)
 	go func() {
-
+		// Read the client preface
 		buf := make([]byte, len(http2ClientPreface))
 		if _, err := io.ReadFull(sc.conn, buf); err != nil {
 			errc <- err
@@ -3614,7 +4598,7 @@
 			errc <- nil
 		}
 	}()
-	timer := time.NewTimer(http2prefaceTimeout)
+	timer := time.NewTimer(http2prefaceTimeout) // TODO: configurable on *Server?
 	defer timer.Stop()
 	select {
 	case <-timer.C:
@@ -3658,7 +4642,13 @@
 	case <-sc.doneServing:
 		return http2errClientDisconnected
 	case <-stream.cw:
-
+		// If both ch and stream.cw were ready (as might
+		// happen on the final Write after an http.Handler
+		// ends), prefer the write result. Otherwise this
+		// might just be us successfully closing the stream.
+		// The writeFrameAsync and serve goroutines guarantee
+		// that the ch send will happen before the stream.cw
+		// close.
 		select {
 		case err = <-ch:
 			frameWriteDone = true
@@ -3681,12 +4671,13 @@
 // buffered and is read by serve itself). If you're on the serve
 // goroutine, call writeFrame instead.
 func (sc *http2serverConn) writeFrameFromHandler(wr http2FrameWriteRequest) error {
-	sc.serveG.checkNotOn()
+	sc.serveG.checkNotOn() // NOT
 	select {
 	case sc.wantWriteFrameCh <- wr:
 		return nil
 	case <-sc.doneServing:
-
+		// Serve loop is gone.
+		// Client has closed their connection to the server.
 		return http2errClientDisconnected
 	}
 }
@@ -3705,6 +4696,24 @@
 	// If true, wr will not be written and wr.done will not be signaled.
 	var ignoreWrite bool
 
+	// We are not allowed to write frames on closed streams. RFC 7540 Section
+	// 5.1.1 says: "An endpoint MUST NOT send frames other than PRIORITY on
+	// a closed stream." Our server never sends PRIORITY, so that exception
+	// does not apply.
+	//
+	// The serverConn might close an open stream while the stream's handler
+	// is still running. For example, the server might close a stream when it
+	// receives bad data from the client. If this happens, the handler might
+	// attempt to write a frame after the stream has been closed (since the
+	// handler hasn't yet been notified of the close). In this case, we simply
+	// ignore the frame. The handler will notice that the stream is closed when
+	// it waits for the frame to be written.
+	//
+	// As an exception to this rule, we allow sending RST_STREAM after close.
+	// This allows us to immediately reject new streams without tracking any
+	// state for those streams (except for the queued RST_STREAM frame). This
+	// may result in duplicate RST_STREAMs in some cases, but the client should
+	// ignore those.
 	if wr.StreamID() != 0 {
 		_, isReset := wr.write.(http2StreamError)
 		if state, _ := sc.state(wr.StreamID()); state == http2stateClosed && !isReset {
@@ -3712,12 +4721,15 @@
 		}
 	}
 
+	// Don't send a 100-continue response if we've already sent headers.
+	// See golang.org/issue/14030.
 	switch wr.write.(type) {
 	case *http2writeResHeaders:
 		wr.stream.wroteHeaders = true
 	case http2write100ContinueHeadersFrame:
 		if wr.stream.wroteHeaders {
-
+			// We do not need to notify wr.done because this frame is
+			// never written with wr.done != nil.
 			if wr.done != nil {
 				panic("wr.done != nil for write100ContinueHeadersFrame")
 			}
@@ -3746,7 +4758,8 @@
 		case http2stateHalfClosedLocal:
 			switch wr.write.(type) {
 			case http2StreamError, http2handlerPanicRST, http2writeWindowUpdate:
-
+				// RFC 7540 Section 5.1 allows sending RST_STREAM, PRIORITY, and WINDOW_UPDATE
+				// in this state. (We never send PRIORITY from the server, so that is not checked.)
 			default:
 				panic(fmt.Sprintf("internal error: attempt to send frame on a half-closed-local stream: %v", wr))
 			}
@@ -3800,16 +4813,29 @@
 		}
 		switch st.state {
 		case http2stateOpen:
-
+			// Here we would go to stateHalfClosedLocal in
+			// theory, but since our handler is done and
+			// the net/http package provides no mechanism
+			// for closing a ResponseWriter while still
+			// reading data (see possible TODO at top of
+			// this file), we go into closed state here
+			// anyway, after telling the peer we're
+			// hanging up on them. We'll transition to
+			// stateClosed after the RST_STREAM frame is
+			// written.
 			st.state = http2stateHalfClosedLocal
-			sc.resetStream(http2streamError(st.id, http2ErrCodeCancel))
+			// Section 8.1: a server MAY request that the client abort
+			// transmission of a request without error by sending a
+			// RST_STREAM with an error code of NO_ERROR after sending
+			// a complete response.
+			sc.resetStream(http2streamError(st.id, http2ErrCodeNo))
 		case http2stateHalfClosedRemote:
 			sc.closeStream(st, http2errHandlerComplete)
 		}
 	} else {
 		switch v := wr.write.(type) {
 		case http2StreamError:
-
+			// st may be unknown if the RST_STREAM was generated to reject bad input.
 			if st, ok := sc.streams[v.StreamID]; ok {
 				sc.closeStream(st, v)
 			}
@@ -3818,6 +4844,7 @@
 		}
 	}
 
+	// Reply (if requested) to unblock the ServeHTTP goroutine.
 	wr.replyToWriter(res.err)
 
 	sc.scheduleFrameWrite()
@@ -3865,7 +4892,7 @@
 		}
 		if sc.needsFrameFlush {
 			sc.startFrameWrite(http2FrameWriteRequest{write: http2flushFrameWriter{}})
-			sc.needsFrameFlush = false
+			sc.needsFrameFlush = false // after startFrameWrite, since it sets this true
 			continue
 		}
 		break
@@ -3873,10 +4900,19 @@
 	sc.inFrameScheduleLoop = false
 }
 
-// startGracefulShutdown sends a GOAWAY with ErrCodeNo to tell the
-// client we're gracefully shutting down. The connection isn't closed
-// until all current streams are done.
+// startGracefulShutdown gracefully shuts down a connection. This
+// sends GOAWAY with ErrCodeNo to tell the client we're gracefully
+// shutting down. The connection isn't closed until all current
+// streams are done.
+//
+// startGracefulShutdown returns immediately; it does not wait until
+// the connection has shut down.
 func (sc *http2serverConn) startGracefulShutdown() {
+	sc.serveG.checkNotOn() // NOT
+	sc.shutdownOnce.Do(func() { sc.sendServeMsg(http2gracefulShutdownMsg) })
+}
+
+func (sc *http2serverConn) startGracefulShutdownInternal() {
 	sc.goAwayIn(http2ErrCodeNo, 0)
 }
 
@@ -3886,7 +4922,7 @@
 	if code != http2ErrCodeNo {
 		forceCloseIn = 250 * time.Millisecond
 	} else {
-
+		// TODO: configurable
 		forceCloseIn = 1 * time.Second
 	}
 	sc.goAwayIn(code, forceCloseIn)
@@ -3908,8 +4944,7 @@
 
 func (sc *http2serverConn) shutDownIn(d time.Duration) {
 	sc.serveG.check()
-	sc.shutdownTimer = time.NewTimer(d)
-	sc.shutdownTimerCh = sc.shutdownTimer.C
+	sc.shutdownTimer = time.AfterFunc(d, sc.onShutdownTimer)
 }
 
 func (sc *http2serverConn) resetStream(se http2StreamError) {
@@ -3929,11 +4964,18 @@
 	if err != nil {
 		if err == http2ErrFrameTooLarge {
 			sc.goAway(http2ErrCodeFrameSize)
-			return true
+			return true // goAway will close the loop
 		}
 		clientGone := err == io.EOF || err == io.ErrUnexpectedEOF || http2isClosedConnError(err)
 		if clientGone {
-
+			// TODO: could we also get into this state if
+			// the peer does a half close
+			// (e.g. CloseWrite) because they're done
+			// sending frames but they're still wanting
+			// our open replies?  Investigate.
+			// TODO: add CloseWrite to crypto/tls.Conn first
+			// so we have a way to test this? I suppose
+			// just for testing we could have a non-TLS mode.
 			return false
 		}
 	} else {
@@ -3957,7 +4999,7 @@
 	case http2ConnectionError:
 		sc.logf("http2: server connection error from %v: %v", sc.conn.RemoteAddr(), ev)
 		sc.goAway(http2ErrCode(ev))
-		return true
+		return true // goAway will handle shutdown
 	default:
 		if res.err != nil {
 			sc.vlogf("http2: server closing client connection; error reading frame from client %s: %v", sc.conn.RemoteAddr(), err)
@@ -3971,6 +5013,7 @@
 func (sc *http2serverConn) processFrame(f http2Frame) error {
 	sc.serveG.check()
 
+	// First frame received must be SETTINGS.
 	if !sc.sawFirstSettings {
 		if _, ok := f.(*http2SettingsFrame); !ok {
 			return http2ConnectionError(http2ErrCodeProtocol)
@@ -3996,7 +5039,8 @@
 	case *http2GoAwayFrame:
 		return sc.processGoAway(f)
 	case *http2PushPromiseFrame:
-
+		// A client cannot push. Thus, servers MUST treat the receipt of a PUSH_PROMISE
+		// frame as a connection error (Section 5.4.1) of type PROTOCOL_ERROR.
 		return http2ConnectionError(http2ErrCodeProtocol)
 	default:
 		sc.vlogf("http2: server ignoring frame: %v", f.Header())
@@ -4007,11 +5051,16 @@
 func (sc *http2serverConn) processPing(f *http2PingFrame) error {
 	sc.serveG.check()
 	if f.IsAck() {
-
+		// 6.7 PING: " An endpoint MUST NOT respond to PING frames
+		// containing this flag."
 		return nil
 	}
 	if f.StreamID != 0 {
-
+		// "PING frames are not associated with any individual
+		// stream. If a PING frame is received with a stream
+		// identifier field value other than 0x0, the recipient MUST
+		// respond with a connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR."
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
 	if sc.inGoAway && sc.goAwayCode != http2ErrCodeNo {
@@ -4024,20 +5073,27 @@
 func (sc *http2serverConn) processWindowUpdate(f *http2WindowUpdateFrame) error {
 	sc.serveG.check()
 	switch {
-	case f.StreamID != 0:
+	case f.StreamID != 0: // stream-level flow control
 		state, st := sc.state(f.StreamID)
 		if state == http2stateIdle {
-
+			// Section 5.1: "Receiving any frame other than HEADERS
+			// or PRIORITY on a stream in this state MUST be
+			// treated as a connection error (Section 5.4.1) of
+			// type PROTOCOL_ERROR."
 			return http2ConnectionError(http2ErrCodeProtocol)
 		}
 		if st == nil {
-
+			// "WINDOW_UPDATE can be sent by a peer that has sent a
+			// frame bearing the END_STREAM flag. This means that a
+			// receiver could receive a WINDOW_UPDATE frame on a "half
+			// closed (remote)" or "closed" stream. A receiver MUST
+			// NOT treat this as an error, see Section 5.1."
 			return nil
 		}
 		if !st.flow.add(int32(f.Increment)) {
 			return http2streamError(f.StreamID, http2ErrCodeFlowControl)
 		}
-	default:
+	default: // connection-level flow control
 		if !sc.flow.add(int32(f.Increment)) {
 			return http2goAwayFlowError{}
 		}
@@ -4051,7 +5107,11 @@
 
 	state, st := sc.state(f.StreamID)
 	if state == http2stateIdle {
-
+		// 6.4 "RST_STREAM frames MUST NOT be sent for a
+		// stream in the "idle" state. If a RST_STREAM frame
+		// identifying an idle stream is received, the
+		// recipient MUST treat this as a connection error
+		// (Section 5.4.1) of type PROTOCOL_ERROR.
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
 	if st != nil {
@@ -4067,6 +5127,9 @@
 		panic(fmt.Sprintf("invariant; can't close stream in state %v", st.state))
 	}
 	st.state = http2stateClosed
+	if st.writeDeadline != nil {
+		st.writeDeadline.Stop()
+	}
 	if st.isPushed() {
 		sc.curPushedStreams--
 	} else {
@@ -4079,16 +5142,17 @@
 			sc.idleTimer.Reset(sc.srv.IdleTimeout)
 		}
 		if http2h1ServerKeepAlivesDisabled(sc.hs) {
-			sc.startGracefulShutdown()
+			sc.startGracefulShutdownInternal()
 		}
 	}
 	if p := st.body; p != nil {
-
+		// Return any buffered unread bytes worth of conn-level flow control.
+		// See golang.org/issue/16481
 		sc.sendWindowUpdate(nil, p.Len())
 
 		p.CloseWithError(err)
 	}
-	st.cw.Close()
+	st.cw.Close() // signals Handler's CloseNotifier, unblocks writes, etc
 	sc.writeSched.CloseStream(st.id)
 }
 
@@ -4097,7 +5161,9 @@
 	if f.IsAck() {
 		sc.unackedSettings--
 		if sc.unackedSettings < 0 {
-
+			// Why is the peer ACKing settings we never sent?
+			// The spec doesn't mention this case, but
+			// hang up on them anyway.
 			return http2ConnectionError(http2ErrCodeProtocol)
 		}
 		return nil
@@ -4129,11 +5195,13 @@
 	case http2SettingInitialWindowSize:
 		return sc.processSettingInitialWindowSize(s.Val)
 	case http2SettingMaxFrameSize:
-		sc.maxFrameSize = int32(s.Val)
+		sc.maxFrameSize = int32(s.Val) // the maximum valid s.Val is < 2^31
 	case http2SettingMaxHeaderListSize:
 		sc.peerMaxHeaderListSize = s.Val
 	default:
-
+		// Unknown setting: "An endpoint that receives a SETTINGS
+		// frame with any unknown or unsupported identifier MUST
+		// ignore that setting."
 		if http2VerboseLogs {
 			sc.vlogf("http2: server ignoring unknown setting %v", s)
 		}
@@ -4143,13 +5211,26 @@
 
 func (sc *http2serverConn) processSettingInitialWindowSize(val uint32) error {
 	sc.serveG.check()
+	// Note: val already validated to be within range by
+	// processSetting's Valid call.
 
-	old := sc.initialWindowSize
-	sc.initialWindowSize = int32(val)
-	growth := sc.initialWindowSize - old
+	// "A SETTINGS frame can alter the initial flow control window
+	// size for all current streams. When the value of
+	// SETTINGS_INITIAL_WINDOW_SIZE changes, a receiver MUST
+	// adjust the size of all stream flow control windows that it
+	// maintains by the difference between the new value and the
+	// old value."
+	old := sc.initialStreamSendWindowSize
+	sc.initialStreamSendWindowSize = int32(val)
+	growth := int32(val) - old // may be negative
 	for _, st := range sc.streams {
 		if !st.flow.add(growth) {
-
+			// 6.9.2 Initial Flow Control Window Size
+			// "An endpoint MUST treat a change to
+			// SETTINGS_INITIAL_WINDOW_SIZE that causes any flow
+			// control window to exceed the maximum size as a
+			// connection error (Section 5.4.1) of type
+			// FLOW_CONTROL_ERROR."
 			return http2ConnectionError(http2ErrCodeFlowControl)
 		}
 	}
@@ -4163,23 +5244,40 @@
 	}
 	data := f.Data()
 
+	// "If a DATA frame is received whose stream is not in "open"
+	// or "half closed (local)" state, the recipient MUST respond
+	// with a stream error (Section 5.4.2) of type STREAM_CLOSED."
 	id := f.Header().StreamID
 	state, st := sc.state(id)
 	if id == 0 || state == http2stateIdle {
-
+		// Section 5.1: "Receiving any frame other than HEADERS
+		// or PRIORITY on a stream in this state MUST be
+		// treated as a connection error (Section 5.4.1) of
+		// type PROTOCOL_ERROR."
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
 	if st == nil || state != http2stateOpen || st.gotTrailerHeader || st.resetQueued {
+		// This includes sending a RST_STREAM if the stream is
+		// in stateHalfClosedLocal (which currently means that
+		// the http.Handler returned, so it's done reading &
+		// done writing). Try to stop the client from sending
+		// more DATA.
 
+		// But still enforce their connection-level flow control,
+		// and return any flow control bytes since we're not going
+		// to consume them.
 		if sc.inflow.available() < int32(f.Length) {
 			return http2streamError(id, http2ErrCodeFlowControl)
 		}
-
+		// Deduct the flow control from inflow, since we're
+		// going to immediately add it back in
+		// sendWindowUpdate, which also schedules sending the
+		// frames.
 		sc.inflow.take(int32(f.Length))
-		sc.sendWindowUpdate(nil, int(f.Length))
+		sc.sendWindowUpdate(nil, int(f.Length)) // conn-level
 
 		if st != nil && st.resetQueued {
-
+			// Already have a stream error in flight. Don't send another.
 			return nil
 		}
 		return http2streamError(id, http2ErrCodeStreamClosed)
@@ -4188,12 +5286,13 @@
 		panic("internal error: should have a body in this state")
 	}
 
+	// Sender sending more than they'd declared?
 	if st.declBodyBytes != -1 && st.bodyBytes+int64(len(data)) > st.declBodyBytes {
 		st.body.CloseWithError(fmt.Errorf("sender tried to send more than declared Content-Length of %d bytes", st.declBodyBytes))
 		return http2streamError(id, http2ErrCodeStreamClosed)
 	}
 	if f.Length > 0 {
-
+		// Check whether the client has flow control quota.
 		if st.inflow.available() < int32(f.Length) {
 			return http2streamError(id, http2ErrCodeFlowControl)
 		}
@@ -4210,6 +5309,8 @@
 			st.bodyBytes += int64(len(data))
 		}
 
+		// Return any padded flow control now, since we won't
+		// refund it later on body reads.
 		if pad := int32(f.Length) - int32(len(data)); pad > 0 {
 			sc.sendWindowUpdate32(nil, pad)
 			sc.sendWindowUpdate32(st, pad)
@@ -4228,8 +5329,9 @@
 	} else {
 		sc.vlogf("http2: received GOAWAY %+v, starting graceful shutdown", f)
 	}
-	sc.startGracefulShutdown()
-
+	sc.startGracefulShutdownInternal()
+	// http://tools.ietf.org/html/rfc7540#section-6.8
+	// We should not create any new streams, which means we should disable push.
 	sc.pushEnabled = false
 	return nil
 }
@@ -4260,32 +5362,51 @@
 func (st *http2stream) copyTrailersToHandlerRequest() {
 	for k, vv := range st.trailer {
 		if _, ok := st.reqTrailer[k]; ok {
-
+			// Only copy it over it was pre-declared.
 			st.reqTrailer[k] = vv
 		}
 	}
 }
 
+// onWriteTimeout is run on its own goroutine (from time.AfterFunc)
+// when the stream's WriteTimeout has fired.
+func (st *http2stream) onWriteTimeout() {
+	st.sc.writeFrameFromHandler(http2FrameWriteRequest{write: http2streamError(st.id, http2ErrCodeInternal)})
+}
+
 func (sc *http2serverConn) processHeaders(f *http2MetaHeadersFrame) error {
 	sc.serveG.check()
 	id := f.StreamID
 	if sc.inGoAway {
-
+		// Ignore.
 		return nil
 	}
-
+	// http://tools.ietf.org/html/rfc7540#section-5.1.1
+	// Streams initiated by a client MUST use odd-numbered stream
+	// identifiers. [...] An endpoint that receives an unexpected
+	// stream identifier MUST respond with a connection error
+	// (Section 5.4.1) of type PROTOCOL_ERROR.
 	if id%2 != 1 {
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
-
+	// A HEADERS frame can be used to create a new stream or
+	// send a trailer for an open one. If we already have a stream
+	// open, let it process its own HEADERS frame (trailers at this
+	// point, if it's valid).
 	if st := sc.streams[f.StreamID]; st != nil {
 		if st.resetQueued {
-
+			// We're sending RST_STREAM to close the stream, so don't bother
+			// processing this frame.
 			return nil
 		}
 		return st.processTrailerHeaders(f)
 	}
 
+	// [...] The identifier of a newly established stream MUST be
+	// numerically greater than all streams that the initiating
+	// endpoint has opened or reserved. [...]  An endpoint that
+	// receives an unexpected stream identifier MUST respond with
+	// a connection error (Section 5.4.1) of type PROTOCOL_ERROR.
 	if id <= sc.maxClientStreamID {
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
@@ -4295,12 +5416,22 @@
 		sc.idleTimer.Stop()
 	}
 
+	// http://tools.ietf.org/html/rfc7540#section-5.1.2
+	// [...] Endpoints MUST NOT exceed the limit set by their peer. An
+	// endpoint that receives a HEADERS frame that causes their
+	// advertised concurrent stream limit to be exceeded MUST treat
+	// this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR
+	// or REFUSED_STREAM.
 	if sc.curClientStreams+1 > sc.advMaxStreams {
 		if sc.unackedSettings == 0 {
-
+			// They should know better.
 			return http2streamError(id, http2ErrCodeProtocol)
 		}
-
+		// Assume it's a network race, where they just haven't
+		// received our last SETTINGS update. But actually
+		// this can't happen yet, because we don't yet provide
+		// a way for users to adjust server parameters at
+		// runtime.
 		return http2streamError(id, http2ErrCodeRefusedStream)
 	}
 
@@ -4325,17 +5456,24 @@
 	if st.reqTrailer != nil {
 		st.trailer = make(Header)
 	}
-	st.body = req.Body.(*http2requestBody).pipe
+	st.body = req.Body.(*http2requestBody).pipe // may be nil
 	st.declBodyBytes = req.ContentLength
 
 	handler := sc.handler.ServeHTTP
 	if f.Truncated {
-
+		// Their header list was too long. Send a 431 error.
 		handler = http2handleHeaderListTooLong
 	} else if err := http2checkValidHTTP2RequestHeaders(req.Header); err != nil {
 		handler = http2new400Handler(err)
 	}
 
+	// The net/http package sets the read deadline from the
+	// http.Server.ReadTimeout during the TLS handshake, but then
+	// passes the connection off to us with the deadline already
+	// set. Disarm it here after the request headers are read,
+	// similar to how the http1 server works. Here it's
+	// technically more like the http1 Server's ReadHeaderTimeout
+	// (in Go 1.8), though. That's a more sane option anyway.
 	if sc.hs.ReadTimeout != 0 {
 		sc.conn.SetReadDeadline(time.Time{})
 	}
@@ -4362,7 +5500,9 @@
 		for _, hf := range f.RegularFields() {
 			key := sc.canonicalHeader(hf.Name)
 			if !http2ValidTrailerHeader(key) {
-
+				// TODO: send more details to the peer somehow. But http2 has
+				// no way to send debug data at a stream level. Discuss with
+				// HTTP folk.
 				return http2streamError(st.id, http2ErrCodeProtocol)
 			}
 			st.trailer[key] = append(st.trailer[key], hf.Value)
@@ -4374,7 +5514,10 @@
 
 func http2checkPriority(streamID uint32, p http2PriorityParam) error {
 	if streamID == p.StreamDep {
-
+		// Section 5.3.1: "A stream cannot depend on itself. An endpoint MUST treat
+		// this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR."
+		// Section 5.3.3 says that a stream can depend on one of its dependencies,
+		// so it's only self-dependencies that are forbidden.
 		return http2streamError(streamID, http2ErrCodeProtocol)
 	}
 	return nil
@@ -4406,10 +5549,13 @@
 		cancelCtx: cancelCtx,
 	}
 	st.cw.Init()
-	st.flow.conn = &sc.flow
-	st.flow.add(sc.initialWindowSize)
-	st.inflow.conn = &sc.inflow
-	st.inflow.add(http2initialWindowSize)
+	st.flow.conn = &sc.flow // link to conn-level counter
+	st.flow.add(sc.initialStreamSendWindowSize)
+	st.inflow.conn = &sc.inflow // link to conn-level counter
+	st.inflow.add(sc.srv.initialStreamRecvWindowSize())
+	if sc.hs.WriteTimeout != 0 {
+		st.writeDeadline = time.AfterFunc(sc.hs.WriteTimeout, st.onWriteTimeout)
+	}
 
 	sc.streams[id] = st
 	sc.writeSched.OpenStream(st.id, http2OpenStreamOptions{PusherID: pusherID})
@@ -4441,13 +5587,22 @@
 			return nil, nil, http2streamError(f.StreamID, http2ErrCodeProtocol)
 		}
 	} else if rp.method == "" || rp.path == "" || (rp.scheme != "https" && rp.scheme != "http") {
-
+		// See 8.1.2.6 Malformed Requests and Responses:
+		//
+		// Malformed requests or responses that are detected
+		// MUST be treated as a stream error (Section 5.4.2)
+		// of type PROTOCOL_ERROR."
+		//
+		// 8.1.2.3 Request Pseudo-Header Fields
+		// "All HTTP/2 requests MUST include exactly one valid
+		// value for the :method, :scheme, and :path
+		// pseudo-header fields"
 		return nil, nil, http2streamError(f.StreamID, http2ErrCodeProtocol)
 	}
 
 	bodyOpen := !f.StreamEnded()
 	if rp.method == "HEAD" && bodyOpen {
-
+		// HEAD requests can't have bodies
 		return nil, nil, http2streamError(f.StreamID, http2ErrCodeProtocol)
 	}
 
@@ -4464,16 +5619,14 @@
 		return nil, nil, err
 	}
 	if bodyOpen {
-		st.reqBuf = http2getRequestBodyBuf()
-		req.Body.(*http2requestBody).pipe = &http2pipe{
-			b: &http2fixedBuffer{buf: st.reqBuf},
-		}
-
 		if vv, ok := rp.header["Content-Length"]; ok {
 			req.ContentLength, _ = strconv.ParseInt(vv[0], 10, 64)
 		} else {
 			req.ContentLength = -1
 		}
+		req.Body.(*http2requestBody).pipe = &http2pipe{
+			b: &http2dataBuffer{expected: req.ContentLength},
+		}
 	}
 	return rw, req, nil
 }
@@ -4496,7 +5649,7 @@
 	if needsContinue {
 		rp.header.Del("Expect")
 	}
-
+	// Merge Cookie headers into one "; "-delimited value.
 	if cookies := rp.header["Cookie"]; len(cookies) > 1 {
 		rp.header.Set("Cookie", strings.Join(cookies, "; "))
 	}
@@ -4508,7 +5661,8 @@
 			key = CanonicalHeaderKey(strings.TrimSpace(key))
 			switch key {
 			case "Transfer-Encoding", "Trailer", "Content-Length":
-
+				// Bogus. (copy of http1 rules)
+				// Ignore.
 			default:
 				if trailer == nil {
 					trailer = make(Header)
@@ -4523,7 +5677,7 @@
 	var requestURI string
 	if rp.method == "CONNECT" {
 		url_ = &url.URL{Host: rp.authority}
-		requestURI = rp.authority
+		requestURI = rp.authority // mimic HTTP/1 server behavior
 	} else {
 		var err error
 		url_, err = url.ParseRequestURI(rp.path)
@@ -4556,7 +5710,7 @@
 
 	rws := http2responseWriterStatePool.Get().(*http2responseWriterState)
 	bwSave := rws.bw
-	*rws = http2responseWriterState{}
+	*rws = http2responseWriterState{} // zero all the fields
 	rws.conn = sc
 	rws.bw = bwSave
 	rws.bw.Reset(http2chunkWriter{rws})
@@ -4568,24 +5722,6 @@
 	return rw, req, nil
 }
 
-var http2reqBodyCache = make(chan []byte, 8)
-
-func http2getRequestBodyBuf() []byte {
-	select {
-	case b := <-http2reqBodyCache:
-		return b
-	default:
-		return make([]byte, http2initialWindowSize)
-	}
-}
-
-func http2putRequestBodyBuf(b []byte) {
-	select {
-	case http2reqBodyCache <- b:
-	default:
-	}
-}
-
 // Run on its own goroutine.
 func (sc *http2serverConn) runHandler(rw *http2responseWriter, req *Request, handler func(ResponseWriter, *Request)) {
 	didPanic := true
@@ -4597,7 +5733,7 @@
 				write:  http2handlerPanicRST{rw.rws.stream.id},
 				stream: rw.rws.stream,
 			})
-
+			// Same as net/http:
 			if http2shouldLogPanic(e) {
 				const size = 64 << 10
 				buf := make([]byte, size)
@@ -4625,10 +5761,13 @@
 // called from handler goroutines.
 // h may be nil.
 func (sc *http2serverConn) writeHeaders(st *http2stream, headerData *http2writeResHeaders) error {
-	sc.serveG.checkNotOn()
+	sc.serveG.checkNotOn() // NOT on
 	var errc chan error
 	if headerData.h != nil {
-
+		// If there's a header map (which we don't own), so we have to block on
+		// waiting for this frame to be written, so an http.Flush mid-handler
+		// writes out the correct value of keys, before a handler later potentially
+		// mutates it.
 		errc = http2errChanPool.Get().(chan error)
 	}
 	if err := sc.writeFrameFromHandler(http2FrameWriteRequest{
@@ -4671,26 +5810,21 @@
 // Notes that the handler for the given stream ID read n bytes of its body
 // and schedules flow control tokens to be sent.
 func (sc *http2serverConn) noteBodyReadFromHandler(st *http2stream, n int, err error) {
-	sc.serveG.checkNotOn()
+	sc.serveG.checkNotOn() // NOT on
 	if n > 0 {
 		select {
 		case sc.bodyReadCh <- http2bodyReadMsg{st, n}:
 		case <-sc.doneServing:
 		}
 	}
-	if err == io.EOF {
-		if buf := st.reqBuf; buf != nil {
-			st.reqBuf = nil
-			http2putRequestBodyBuf(buf)
-		}
-	}
 }
 
 func (sc *http2serverConn) noteBodyRead(st *http2stream, n int) {
 	sc.serveG.check()
-	sc.sendWindowUpdate(nil, n)
+	sc.sendWindowUpdate(nil, n) // conn-level
 	if st.state != http2stateHalfClosedRemote && st.state != http2stateClosed {
-
+		// Don't send this WINDOW_UPDATE if the stream is closed
+		// remotely.
 		sc.sendWindowUpdate(st, n)
 	}
 }
@@ -4777,8 +5911,8 @@
 	return
 }
 
-// responseWriter is the http.ResponseWriter implementation.  It's
-// intentionally small (1 pointer wide) to minimize garbage.  The
+// responseWriter is the http.ResponseWriter implementation. It's
+// intentionally small (1 pointer wide) to minimize garbage. The
 // responseWriterState pointer inside is zeroed at the end of a
 // request (in handlerDone) and calls on the responseWriter thereafter
 // simply crash (caller's mistake), but the much larger responseWriterState
@@ -4812,6 +5946,7 @@
 	wroteHeader   bool     // WriteHeader called (explicitly or implicitly). Not necessarily sent to user yet.
 	sentHeader    bool     // have we sent the header frame?
 	handlerDone   bool     // handler has finished
+	dirty         bool     // a Write failed; don't reuse this responseWriterState
 
 	sentContentLen int64 // non-zero if handler set a Content-Length header
 	wroteBytes     int64
@@ -4832,7 +5967,7 @@
 func (rws *http2responseWriterState) declareTrailer(k string) {
 	k = CanonicalHeaderKey(k)
 	if !http2ValidTrailerHeader(k) {
-
+		// Forbidden by RFC 2616 14.40.
 		rws.conn.logf("ignoring invalid trailer %q", k)
 		return
 	}
@@ -4874,7 +6009,7 @@
 		}
 		var date string
 		if _, ok := rws.snapHeader["Date"]; !ok {
-
+			// TODO(bradfitz): be faster here, like net/http? measure.
 			date = time.Now().UTC().Format(TimeFormat)
 		}
 
@@ -4893,6 +6028,7 @@
 			date:          date,
 		})
 		if err != nil {
+			rws.dirty = true
 			return 0, err
 		}
 		if endStream {
@@ -4912,8 +6048,9 @@
 
 	endStream := rws.handlerDone && !rws.hasTrailers()
 	if len(p) > 0 || endStream {
-
+		// only send a 0 byte DATA frame if we're ending the stream.
 		if err := rws.conn.writeDataFromHandler(rws.stream, p, endStream); err != nil {
+			rws.dirty = true
 			return 0, err
 		}
 	}
@@ -4925,6 +6062,9 @@
 			trailers:  rws.trailers,
 			endStream: true,
 		})
+		if err != nil {
+			rws.dirty = true
+		}
 		return len(p), err
 	}
 	return len(p), nil
@@ -4952,7 +6092,7 @@
 // says you SHOULD (but not must) predeclare any trailers in the
 // header, the official ResponseWriter rules said trailers in Go must
 // be predeclared, and then we reuse the same ResponseWriter.Header()
-// map to mean both Headers and Trailers.  When it's time to write the
+// map to mean both Headers and Trailers. When it's time to write the
 // Trailers, we pick out the fields of Headers that were declared as
 // trailers. That worked for a while, until we found the first major
 // user of Trailers in the wild: gRPC (using them only over http2),
@@ -4989,11 +6129,14 @@
 	}
 	if rws.bw.Buffered() > 0 {
 		if err := rws.bw.Flush(); err != nil {
-
+			// Ignore the error. The frame writer already knows.
 			return
 		}
 	} else {
-
+		// The bufio.Writer won't call chunkWriter.Write
+		// (writeChunk with zero bytes, so we have to do it
+		// ourselves to force the HTTP response header and/or
+		// final DATA frame (with END_STREAM) to be sent.
 		rws.writeChunk(nil)
 	}
 }
@@ -5010,7 +6153,7 @@
 		rws.closeNotifierCh = ch
 		cw := rws.stream.cw
 		go func() {
-			cw.Wait()
+			cw.Wait() // wait for close
 			ch <- true
 		}()
 	}
@@ -5061,7 +6204,7 @@
 //
 // * Handler calls w.Write or w.WriteString ->
 // * -> rws.bw (*bufio.Writer) ->
-// * (Handler migth call Flush)
+// * (Handler might call Flush)
 // * -> chunkWriter{rws}
 // * -> responseWriterState.writeChunk(p []byte)
 // * -> responseWriterState.writeChunk (most of the magic; see comment there)
@@ -5085,9 +6228,9 @@
 	if !http2bodyAllowedForStatus(rws.status) {
 		return 0, ErrBodyNotAllowed
 	}
-	rws.wroteBytes += int64(len(dataB)) + int64(len(dataS))
+	rws.wroteBytes += int64(len(dataB)) + int64(len(dataS)) // only one can be set
 	if rws.sentContentLen != 0 && rws.wroteBytes > rws.sentContentLen {
-
+		// TODO: send a RST_STREAM
 		return 0, errors.New("http2: handler wrote more than declared Content-Length")
 	}
 
@@ -5100,10 +6243,19 @@
 
 func (w *http2responseWriter) handlerDone() {
 	rws := w.rws
+	dirty := rws.dirty
 	rws.handlerDone = true
 	w.Flush()
 	w.rws = nil
-	http2responseWriterStatePool.Put(rws)
+	if !dirty {
+		// Only recycle the pool if all prior Write calls to
+		// the serverConn goroutine completed successfully. If
+		// they returned earlier due to resets from the peer
+		// there might still be write goroutines outstanding
+		// from the serverConn referencing the rws memory. See
+		// issue 20704.
+		http2responseWriterStatePool.Put(rws)
+	}
 }
 
 // Push errors.
@@ -5124,10 +6276,13 @@
 	sc := st.sc
 	sc.serveG.checkNotOn()
 
+	// No recursive pushes: "PUSH_PROMISE frames MUST only be sent on a peer-initiated stream."
+	// http://tools.ietf.org/html/rfc7540#section-6.6
 	if st.isPushed() {
 		return http2ErrRecursivePush
 	}
 
+	// Default options.
 	if opts.Method == "" {
 		opts.Method = "GET"
 	}
@@ -5139,6 +6294,7 @@
 		wantScheme = "https"
 	}
 
+	// Validate the request.
 	u, err := url.Parse(target)
 	if err != nil {
 		return err
@@ -5161,7 +6317,10 @@
 		if strings.HasPrefix(k, ":") {
 			return fmt.Errorf("promised request headers cannot include pseudo header %q", k)
 		}
-
+		// These headers are meaningful only if the request has a body,
+		// but PUSH_PROMISE requests cannot have a body.
+		// http://tools.ietf.org/html/rfc7540#section-8.2
+		// Also disallow Host, since the promised URL must be absolute.
 		switch strings.ToLower(k) {
 		case "content-length", "content-encoding", "trailer", "te", "expect", "host":
 			return fmt.Errorf("promised request headers cannot include %q", k)
@@ -5171,11 +6330,14 @@
 		return err
 	}
 
+	// The RFC effectively limits promised requests to GET and HEAD:
+	// "Promised requests MUST be cacheable [GET, HEAD, or POST], and MUST be safe [GET or HEAD]"
+	// http://tools.ietf.org/html/rfc7540#section-8.2
 	if opts.Method != "GET" && opts.Method != "HEAD" {
 		return fmt.Errorf("method %q must be GET or HEAD", opts.Method)
 	}
 
-	msg := http2startPushRequest{
+	msg := &http2startPushRequest{
 		parent: st,
 		method: opts.Method,
 		url:    u,
@@ -5188,7 +6350,7 @@
 		return http2errClientDisconnected
 	case <-st.cw:
 		return http2errStreamClosed
-	case sc.wantStartPushCh <- msg:
+	case sc.serveMsgCh <- msg:
 	}
 
 	select {
@@ -5210,48 +6372,66 @@
 	done   chan error
 }
 
-func (sc *http2serverConn) startPush(msg http2startPushRequest) {
+func (sc *http2serverConn) startPush(msg *http2startPushRequest) {
 	sc.serveG.check()
 
+	// http://tools.ietf.org/html/rfc7540#section-6.6.
+	// PUSH_PROMISE frames MUST only be sent on a peer-initiated stream that
+	// is in either the "open" or "half-closed (remote)" state.
 	if msg.parent.state != http2stateOpen && msg.parent.state != http2stateHalfClosedRemote {
-
+		// responseWriter.Push checks that the stream is peer-initiaed.
 		msg.done <- http2errStreamClosed
 		return
 	}
 
+	// http://tools.ietf.org/html/rfc7540#section-6.6.
 	if !sc.pushEnabled {
 		msg.done <- ErrNotSupported
 		return
 	}
 
+	// PUSH_PROMISE frames must be sent in increasing order by stream ID, so
+	// we allocate an ID for the promised stream lazily, when the PUSH_PROMISE
+	// is written. Once the ID is allocated, we start the request handler.
 	allocatePromisedID := func() (uint32, error) {
 		sc.serveG.check()
 
+		// Check this again, just in case. Technically, we might have received
+		// an updated SETTINGS by the time we got around to writing this frame.
 		if !sc.pushEnabled {
 			return 0, ErrNotSupported
 		}
-
+		// http://tools.ietf.org/html/rfc7540#section-6.5.2.
 		if sc.curPushedStreams+1 > sc.clientMaxStreams {
 			return 0, http2ErrPushLimitReached
 		}
 
+		// http://tools.ietf.org/html/rfc7540#section-5.1.1.
+		// Streams initiated by the server MUST use even-numbered identifiers.
+		// A server that is unable to establish a new stream identifier can send a GOAWAY
+		// frame so that the client is forced to open a new connection for new streams.
 		if sc.maxPushPromiseID+2 >= 1<<31 {
-			sc.startGracefulShutdown()
+			sc.startGracefulShutdownInternal()
 			return 0, http2ErrPushLimitReached
 		}
 		sc.maxPushPromiseID += 2
 		promisedID := sc.maxPushPromiseID
 
+		// http://tools.ietf.org/html/rfc7540#section-8.2.
+		// Strictly speaking, the new stream should start in "reserved (local)", then
+		// transition to "half closed (remote)" after sending the initial HEADERS, but
+		// we start in "half closed (remote)" for simplicity.
+		// See further comments at the definition of stateHalfClosedRemote.
 		promised := sc.newStream(promisedID, msg.parent.id, http2stateHalfClosedRemote)
 		rw, req, err := sc.newWriterAndRequestNoBody(promised, http2requestParam{
 			method:    msg.method,
 			scheme:    msg.url.Scheme,
 			authority: msg.url.Host,
 			path:      msg.url.RequestURI(),
-			header:    http2cloneHeader(msg.header),
+			header:    http2cloneHeader(msg.header), // clone since handler runs concurrently with writing the PUSH_PROMISE
 		})
 		if err != nil {
-
+			// Should not happen, since we've already validated msg.url.
 			panic(fmt.Sprintf("newWriterAndRequestNoBody(%+v): %v", msg.url, err))
 		}
 
@@ -5356,31 +6536,6 @@
 	"Www-Authenticate":    true,
 }
 
-// h1ServerShutdownChan returns a channel that will be closed when the
-// provided *http.Server wants to shut down.
-//
-// This is a somewhat hacky way to get at http1 innards. It works
-// when the http2 code is bundled into the net/http package in the
-// standard library. The alternatives ended up making the cmd/go tool
-// depend on http Servers. This is the lightest option for now.
-// This is tested via the TestServeShutdown* tests in net/http.
-func http2h1ServerShutdownChan(hs *Server) <-chan struct{} {
-	if fn := http2testh1ServerShutdownChan; fn != nil {
-		return fn(hs)
-	}
-	var x interface{} = hs
-	type I interface {
-		getDoneChan() <-chan struct{}
-	}
-	if hs, ok := x.(I); ok {
-		return hs.getDoneChan()
-	}
-	return nil
-}
-
-// optional test hook for h1ServerShutdownChan.
-var http2testh1ServerShutdownChan func(hs *Server) <-chan struct{}
-
 // h1ServerKeepAlivesDisabled reports whether hs has its keep-alives
 // disabled. See comments on h1ServerShutdownChan above for why
 // the code is written this way.
@@ -5486,7 +6641,7 @@
 // It requires Go 1.6 or later and returns an error if the net/http package is too old
 // or if t1 has already been HTTP/2-enabled.
 func http2ConfigureTransport(t1 *Transport) error {
-	_, err := http2configureTransport(t1)
+	_, err := http2configureTransport(t1) // in configure_transport.go (go1.6) or not_go16.go
 	return err
 }
 
@@ -5669,7 +6824,7 @@
 // and returns a host:port. The port 443 is added if needed.
 func http2authorityAddr(scheme string, authority string) (addr string) {
 	host, port, err := net.SplitHostPort(authority)
-	if err != nil {
+	if err != nil { // authority didn't have a port
 		port = "443"
 		if scheme == "http" {
 			port = "80"
@@ -5679,7 +6834,7 @@
 	if a, err := idna.ToASCII(host); err == nil {
 		host = a
 	}
-
+	// IPv6 address literal, without a port:
 	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
 		return host + ":" + port
 	}
@@ -5742,12 +6897,14 @@
 	case http2errClientConnUnusable, http2errClientConnGotGoAway:
 		return req, nil
 	case http2errClientConnGotGoAwayAfterSomeReqBody:
-
+		// If the Body is nil (or http.NoBody), it's safe to reuse
+		// this request and its Body.
 		if req.Body == nil || http2reqBodyIsNoBody(req.Body) {
 			return req, nil
 		}
-
-		getBody := http2reqGetBody(req)
+		// Otherwise we depend on the Request having its GetBody
+		// func defined.
+		getBody := http2reqGetBody(req) // Go 1.8: getBody = req.GetBody
 		if getBody == nil {
 			return nil, errors.New("http2: Transport: peer server initiated graceful shutdown after some of Request.Body was written; define Request.GetBody to avoid this error")
 		}
@@ -5840,9 +6997,9 @@
 		tconn:                c,
 		readerDone:           make(chan struct{}),
 		nextStreamID:         1,
-		maxFrameSize:         16 << 10,
-		initialWindowSize:    65535,
-		maxConcurrentStreams: 1000,
+		maxFrameSize:         16 << 10, // spec default
+		initialWindowSize:    65535,    // spec default
+		maxConcurrentStreams: 1000,     // "infinite", per spec. 1000 seems good enough.
 		streams:              make(map[uint32]*http2clientStream),
 		singleUse:            singleUse,
 		wantSettingsAck:      true,
@@ -5859,12 +7016,16 @@
 	cc.cond = sync.NewCond(&cc.mu)
 	cc.flow.add(int32(http2initialWindowSize))
 
+	// TODO: adjust this writer size to account for frame size +
+	// MTU + crypto/tls record padding.
 	cc.bw = bufio.NewWriter(http2stickyErrWriter{c, &cc.werr})
 	cc.br = bufio.NewReader(c)
 	cc.fr = http2NewFramer(cc.bw, cc.br)
 	cc.fr.ReadMetaHeaders = hpack.NewDecoder(http2initialHeaderTableSize, nil)
 	cc.fr.MaxHeaderListSize = t.maxHeaderListSize()
 
+	// TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on
+	// henc in response to SETTINGS frames?
 	cc.henc = hpack.NewEncoder(&cc.hbuf)
 
 	if cs, ok := c.(http2connectionStater); ok {
@@ -5900,6 +7061,7 @@
 	old := cc.goAway
 	cc.goAway = f
 
+	// Merge the previous and current GoAway error frames.
 	if cc.goAwayDebug == "" {
 		cc.goAwayDebug = string(f.DebugData())
 	}
@@ -5932,7 +7094,7 @@
 		cc.nextStreamID < math.MaxInt32
 }
 
-// onIdleTimeout is called from a time.AfterFunc goroutine.  It will
+// onIdleTimeout is called from a time.AfterFunc goroutine. It will
 // only be called when we're idle, but because we're coming from a new
 // goroutine, there could be a new request coming in at the same time,
 // so this simply calls the synchronized closeIfIdle to shut down this
@@ -5950,7 +7112,7 @@
 	}
 	cc.closed = true
 	nextID := cc.nextStreamID
-
+	// TODO: do clients send GOAWAY too? maybe? Just Close:
 	cc.mu.Unlock()
 
 	if http2VerboseLogs {
@@ -5996,7 +7158,7 @@
 			return
 		}
 	}
-
+	// forget about it.
 }
 
 // errRequestCanceled is a copy of net/http's errRequestCanceled because it's not
@@ -6024,7 +7186,10 @@
 	if cc.t.t1 != nil {
 		return cc.t.t1.ResponseHeaderTimeout
 	}
-
+	// No way to do this (yet?) with just an http2.Transport. Probably
+	// no need. Request.Cancel this is the new way. We only need to support
+	// this for compatibility with the old http.Transport fields when
+	// we're doing transparent http2.
 	return 0
 }
 
@@ -6048,7 +7213,7 @@
 // req.ContentLength, where 0 actually means zero (not unknown) and -1
 // means unknown.
 func http2actualContentLength(req *Request) int64 {
-	if req.Body == nil {
+	if req.Body == nil || http2reqBodyIsNoBody(req.Body) {
 		return 0
 	}
 	if req.ContentLength != 0 {
@@ -6079,8 +7244,8 @@
 	}
 
 	body := req.Body
-	hasBody := body != nil
 	contentLen := http2actualContentLength(req)
+	hasBody := contentLen != 0
 
 	// TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere?
 	var requestedGzip bool
@@ -6088,10 +7253,24 @@
 		req.Header.Get("Accept-Encoding") == "" &&
 		req.Header.Get("Range") == "" &&
 		req.Method != "HEAD" {
-
+		// Request gzip only, not deflate. Deflate is ambiguous and
+		// not as universally supported anyway.
+		// See: http://www.gzip.org/zlib/zlib_faq.html#faq38
+		//
+		// Note that we don't request this for HEAD requests,
+		// due to a bug in nginx:
+		//   http://trac.nginx.org/nginx/ticket/358
+		//   https://golang.org/issue/5522
+		//
+		// We don't request gzip if the request is for a range, since
+		// auto-decoding a portion of a gzipped document will just fail
+		// anyway. See https://golang.org/issue/8923
 		requestedGzip = true
 	}
 
+	// we send: HEADERS{1}, CONTINUATION{0,} + DATA{0,} (DATA is
+	// sent by writeRequestBody below, along with any Trailers,
+	// again in form HEADERS{1}, CONTINUATION{0,})
 	hdrs, err := cc.encodeHeaders(req, requestedGzip, trailers, contentLen)
 	if err != nil {
 		cc.mu.Unlock()
@@ -6114,11 +7293,12 @@
 
 	if werr != nil {
 		if hasBody {
-			req.Body.Close()
+			req.Body.Close() // per RoundTripper contract
 			bodyWriter.cancel()
 		}
 		cc.forgetStreamID(cs.ID)
-
+		// Don't bother sending a RST_STREAM (our write already failed;
+		// no need to keep writing)
 		http2traceWroteRequest(cs.trace, werr)
 		return nil, werr
 	}
@@ -6142,7 +7322,15 @@
 	handleReadLoopResponse := func(re http2resAndError) (*Response, error) {
 		res := re.res
 		if re.err != nil || res.StatusCode > 299 {
-
+			// On error or status code 3xx, 4xx, 5xx, etc abort any
+			// ongoing write, assuming that the server doesn't care
+			// about our request body. If the server replied with 1xx or
+			// 2xx, however, then assume the server DOES potentially
+			// want our body (e.g. full-duplex streaming:
+			// golang.org/issue/13444). If it turns out the server
+			// doesn't, they'll RST_STREAM us soon enough. This is a
+			// heuristic to avoid adding knobs to Transport. Hopefully
+			// we can keep it.
 			bodyWriter.cancel()
 			cs.abortRequestBodyWrite(http2errStopReqBodyWrite)
 		}
@@ -6209,9 +7397,12 @@
 				return handleReadLoopResponse(re)
 			default:
 			}
+			// processResetStream already removed the
+			// stream from the streams map; no need for
+			// forgetStreamID.
 			return nil, cs.resetErr
 		case err := <-bodyWriter.resc:
-
+			// Prefer the read loop's response, if available. Issue 16102.
 			select {
 			case re := <-readLoopResCh:
 				return handleReadLoopResponse(re)
@@ -6232,7 +7423,7 @@
 
 // requires cc.wmu be held
 func (cc *http2ClientConn) writeHeaders(streamID uint32, endStream bool, hdrs []byte) error {
-	first := true
+	first := true // first frame written (HEADERS is first, then CONTINUATION)
 	frameSize := int(cc.maxFrameSize)
 	for len(hdrs) > 0 && cc.werr == nil {
 		chunk := hdrs
@@ -6253,7 +7444,10 @@
 			cc.fr.WriteContinuation(streamID, endHeaders, chunk)
 		}
 	}
-
+	// TODO(bradfitz): this Flush could potentially block (as
+	// could the WriteHeaders call(s) above), which means they
+	// wouldn't respond to Request.Cancel being readable. That's
+	// rare, but this should probably be in a goroutine.
 	cc.bw.Flush()
 	return cc.werr
 }
@@ -6269,13 +7463,16 @@
 
 func (cs *http2clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (err error) {
 	cc := cs.cc
-	sentEnd := false
+	sentEnd := false // whether we sent the final DATA frame w/ END_STREAM
 	buf := cc.frameScratchBuffer()
 	defer cc.putFrameScratchBuffer(buf)
 
 	defer func() {
 		http2traceWroteRequest(cs.trace, err)
-
+		// TODO: write h12Compare test showing whether
+		// Request.Body is closed by the Transport,
+		// and in multiple cases: server replies <=299 and >299
+		// while still writing request body
 		cerr := bodyCloser.Close()
 		if err == nil {
 			err = cerr
@@ -6314,7 +7511,12 @@
 			sentEnd = sawEOF && len(remain) == 0 && !hasTrailers
 			err = cc.fr.WriteData(cs.ID, sentEnd, data)
 			if err == nil {
-
+				// TODO(bradfitz): this flush is for latency, not bandwidth.
+				// Most requests won't need this. Make this opt-in or
+				// opt-out?  Use some heuristic on the body type? Nagel-like
+				// timers?  Based on 'n'? Only last chunk of this for loop,
+				// unless flow control tokens are low? For now, always.
+				// If we change this, see comment below.
 				err = cc.bw.Flush()
 			}
 			cc.wmu.Unlock()
@@ -6325,7 +7527,9 @@
 	}
 
 	if sentEnd {
-
+		// Already sent END_STREAM (which implies we have no
+		// trailers) and flushed, because currently all
+		// WriteData frames above get a flush. So we're done.
 		return nil
 	}
 
@@ -6339,6 +7543,8 @@
 	cc.wmu.Lock()
 	defer cc.wmu.Unlock()
 
+	// Two ways to send END_STREAM: either with trailers, or
+	// with an empty DATA frame.
 	if len(trls) > 0 {
 		err = cc.writeHeaders(cs.ID, true, trls)
 	} else {
@@ -6372,7 +7578,7 @@
 			take := a
 			if int(take) > maxBytes {
 
-				take = int32(maxBytes)
+				take = int32(maxBytes) // can't truncate int; take is int32
 			}
 			if take > int32(cc.maxFrameSize) {
 				take = int32(cc.maxFrameSize)
@@ -6420,6 +7626,9 @@
 		}
 	}
 
+	// Check for any invalid headers and return an error before we
+	// potentially pollute our hpack state. (We want to be able to
+	// continue to reuse the hpack encoder for future requests)
 	for k, vv := range req.Header {
 		if !httplex.ValidHeaderFieldName(k) {
 			return nil, fmt.Errorf("invalid HTTP header name %q", k)
@@ -6431,6 +7640,11 @@
 		}
 	}
 
+	// 8.1.2.3 Request Pseudo-Header Fields
+	// The :path pseudo-header field includes the path and query parts of the
+	// target URI (the path-absolute production and optionally a '?' character
+	// followed by the query production (see Sections 3.3 and 3.4 of
+	// [RFC3986]).
 	cc.writeHeader(":authority", host)
 	cc.writeHeader(":method", req.Method)
 	if req.Method != "CONNECT" {
@@ -6446,13 +7660,20 @@
 		lowKey := strings.ToLower(k)
 		switch lowKey {
 		case "host", "content-length":
-
+			// Host is :authority, already sent.
+			// Content-Length is automatic, set below.
 			continue
 		case "connection", "proxy-connection", "transfer-encoding", "upgrade", "keep-alive":
-
+			// Per 8.1.2.2 Connection-Specific Header
+			// Fields, don't send connection-specific
+			// fields. We have already checked if any
+			// are error-worthy so just ignore the rest.
 			continue
 		case "user-agent":
-
+			// Match Go's http1 behavior: at most one
+			// User-Agent. If set to nil or empty string,
+			// then omit it. Otherwise if not mentioned,
+			// include the default (below).
 			didUA = true
 			if len(vv) < 1 {
 				continue
@@ -6490,7 +7711,8 @@
 	if contentLength < 0 {
 		return false
 	}
-
+	// For zero bodies, whether we send a content-length depends on the method.
+	// It also kinda doesn't matter for http2 either way, with END_STREAM.
 	switch method {
 	case "POST", "PUT", "PATCH":
 		return true
@@ -6503,7 +7725,8 @@
 func (cc *http2ClientConn) encodeTrailers(req *Request) []byte {
 	cc.hbuf.Reset()
 	for k, vv := range req.Trailer {
-
+		// Transfer-Encoding, etc.. have already been filter at the
+		// start of RoundTrip
 		lowKey := strings.ToLower(k)
 		for _, v := range vv {
 			cc.writeHeader(lowKey, v)
@@ -6557,7 +7780,7 @@
 			cc.idleTimer.Reset(cc.idleTimeout)
 		}
 		close(cs.done)
-		cc.cond.Broadcast()
+		cc.cond.Broadcast() // wake up checkResetOrDone via clientStream.awaitFlowControl
 	}
 	return cs
 }
@@ -6616,6 +7839,9 @@
 		cc.idleTimer.Stop()
 	}
 
+	// Close any response bodies if the server closes prematurely.
+	// TODO: also do this if we've written the headers but not
+	// gotten a response yet.
 	err := cc.readerErr
 	cc.mu.Lock()
 	if cc.goAway != nil && http2isEOFOrNetReadError(err) {
@@ -6645,7 +7871,7 @@
 func (rl *http2clientConnReadLoop) run() error {
 	cc := rl.cc
 	rl.closeWhenIdle = cc.t.disableKeepAlives() || cc.singleUse
-	gotReply := false
+	gotReply := false // ever saw a HEADERS reply
 	gotSettings := false
 	for {
 		f, err := cc.fr.ReadFrame()
@@ -6653,7 +7879,7 @@
 			cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err)
 		}
 		if se, ok := err.(http2StreamError); ok {
-			if cs := cc.streamByID(se.StreamID, true); cs != nil {
+			if cs := cc.streamByID(se.StreamID, true /*ended; remove it*/); cs != nil {
 				cs.cc.writeStreamReset(cs.ID, se.Code, err)
 				if se.Cause == nil {
 					se.Cause = cc.fr.errDetail
@@ -6674,7 +7900,7 @@
 			}
 			gotSettings = true
 		}
-		maybeIdle := false
+		maybeIdle := false // whether frame might transition us to idle
 
 		switch f := f.(type) {
 		case *http2MetaHeadersFrame:
@@ -6717,12 +7943,17 @@
 	cc := rl.cc
 	cs := cc.streamByID(f.StreamID, f.StreamEnded())
 	if cs == nil {
-
+		// We'd get here if we canceled a request while the
+		// server had its response still in flight. So if this
+		// was just something we canceled, ignore it.
 		return nil
 	}
 	if !cs.firstByte {
 		if cs.trace != nil {
-
+			// TODO(bradfitz): move first response byte earlier,
+			// when we first read the 9 byte header, not waiting
+			// until all the HEADERS+CONTINUATION frames have been
+			// merged. This works for now.
 			http2traceFirstResponseByte(cs.trace)
 		}
 		cs.firstByte = true
@@ -6738,13 +7969,13 @@
 		if _, ok := err.(http2ConnectionError); ok {
 			return err
 		}
-
+		// Any other error type is a stream error.
 		cs.cc.writeStreamReset(f.StreamID, http2ErrCodeProtocol, err)
 		cs.resc <- http2resAndError{err: err}
-		return nil
+		return nil // return nil from process* funcs to keep conn alive
 	}
 	if res == nil {
-
+		// (nil, nil) special case. See handleResponse docs.
 		return nil
 	}
 	if res.Body != http2noBody {
@@ -6779,9 +8010,9 @@
 	if statusCode == 100 {
 		http2traceGot100Continue(cs.trace)
 		if cs.on100 != nil {
-			cs.on100()
+			cs.on100() // forces any write delay timer to fire
 		}
-		cs.pastHeaders = false
+		cs.pastHeaders = false // do it all again
 		return nil, nil
 	}
 
@@ -6817,10 +8048,12 @@
 			if clen64, err := strconv.ParseInt(clens[0], 10, 64); err == nil {
 				res.ContentLength = clen64
 			} else {
-
+				// TODO: care? unlike http/1, it won't mess up our framing, so it's
+				// more safe smuggling-wise to ignore.
 			}
 		} else if len(clens) > 1 {
-
+			// TODO: care? unlike http/1, it won't mess up our framing, so it's
+			// more safe smuggling-wise to ignore.
 		}
 	}
 
@@ -6829,8 +8062,7 @@
 		return res, nil
 	}
 
-	buf := new(bytes.Buffer)
-	cs.bufPipe = http2pipe{b: buf}
+	cs.bufPipe = http2pipe{b: &http2dataBuffer{expected: res.ContentLength}}
 	cs.bytesRemain = res.ContentLength
 	res.Body = http2transportResponseBody{cs}
 	go cs.awaitRequestCancel(cs.req)
@@ -6847,16 +8079,18 @@
 
 func (rl *http2clientConnReadLoop) processTrailers(cs *http2clientStream, f *http2MetaHeadersFrame) error {
 	if cs.pastTrailers {
-
+		// Too many HEADERS frames for this stream.
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
 	cs.pastTrailers = true
 	if !f.StreamEnded() {
-
+		// We expect that any headers for trailers also
+		// has END_STREAM.
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
 	if len(f.PseudoFields()) > 0 {
-
+		// No pseudo header fields are defined for trailers.
+		// TODO: ConnectionError might be overly harsh? Check.
 		return http2ConnectionError(http2ErrCodeProtocol)
 	}
 
@@ -6904,7 +8138,7 @@
 		}
 	}
 	if n == 0 {
-
+		// No flow control tokens to send back.
 		return
 	}
 
@@ -6912,13 +8146,15 @@
 	defer cc.mu.Unlock()
 
 	var connAdd, streamAdd int32
-
+	// Check the conn-level first, before the stream-level.
 	if v := cc.inflow.available(); v < http2transportDefaultConnFlow/2 {
 		connAdd = http2transportDefaultConnFlow - v
 		cc.inflow.add(connAdd)
 	}
-	if err == nil {
-
+	if err == nil { // No need to refresh if the stream is over or failed.
+		// Consider any buffered body data (read from the conn but not
+		// consumed by the client) when computing flow control for this
+		// stream.
 		v := int(cs.inflow.available()) + cs.bufPipe.Len()
 		if v < http2transportDefaultStreamFlow-http2transportDefaultStreamMinRefresh {
 			streamAdd = int32(http2transportDefaultStreamFlow - v)
@@ -6953,8 +8189,9 @@
 		cc.wmu.Lock()
 		if !serverSentStreamEnd {
 			cc.fr.WriteRSTStream(cs.ID, http2ErrCodeCancel)
+			cs.didReset = true
 		}
-
+		// Return connection-level flow control.
 		if unread > 0 {
 			cc.inflow.add(int32(unread))
 			cc.fr.WriteWindowUpdate(0, uint32(unread))
@@ -6977,11 +8214,16 @@
 		neverSent := cc.nextStreamID
 		cc.mu.Unlock()
 		if f.StreamID >= neverSent {
-
+			// We never asked for this.
 			cc.logf("http2: Transport received unsolicited DATA frame; closing connection")
 			return http2ConnectionError(http2ErrCodeProtocol)
 		}
+		// We probably did ask for this, but canceled. Just ignore it.
+		// TODO: be stricter here? only silently ignore things which
+		// we canceled, but not things which were closed normally
+		// by the peer? Tough without accumulating too much state.
 
+		// But at least return their flow control:
 		if f.Length > 0 {
 			cc.mu.Lock()
 			cc.inflow.add(int32(f.Length))
@@ -6995,12 +8237,7 @@
 		return nil
 	}
 	if f.Length > 0 {
-		if len(data) > 0 && cs.bufPipe.b == nil {
-
-			cc.logf("http2: Transport received DATA frame for closed stream; closing connection")
-			return http2ConnectionError(http2ErrCodeProtocol)
-		}
-
+		// Check connection-level flow control.
 		cc.mu.Lock()
 		if cs.inflow.available() >= int32(f.Length) {
 			cs.inflow.take(int32(f.Length))
@@ -7008,17 +8245,29 @@
 			cc.mu.Unlock()
 			return http2ConnectionError(http2ErrCodeFlowControl)
 		}
-
-		if pad := int32(f.Length) - int32(len(data)); pad > 0 {
-			cs.inflow.add(pad)
-			cc.inflow.add(pad)
+		// Return any padded flow control now, since we won't
+		// refund it later on body reads.
+		var refund int
+		if pad := int(f.Length) - len(data); pad > 0 {
+			refund += pad
+		}
+		// Return len(data) now if the stream is already closed,
+		// since data will never be read.
+		didReset := cs.didReset
+		if didReset {
+			refund += len(data)
+		}
+		if refund > 0 {
+			cc.inflow.add(int32(refund))
 			cc.wmu.Lock()
-			cc.fr.WriteWindowUpdate(0, uint32(pad))
-			cc.fr.WriteWindowUpdate(cs.ID, uint32(pad))
+			cc.fr.WriteWindowUpdate(0, uint32(refund))
+			if !didReset {
+				cs.inflow.add(int32(refund))
+				cc.fr.WriteWindowUpdate(cs.ID, uint32(refund))
+			}
 			cc.bw.Flush()
 			cc.wmu.Unlock()
 		}
-		didReset := cs.didReset
 		cc.mu.Unlock()
 
 		if len(data) > 0 && !didReset {
@@ -7038,7 +8287,8 @@
 var http2errInvalidTrailers = errors.New("http2: invalid trailers")
 
 func (rl *http2clientConnReadLoop) endStream(cs *http2clientStream) {
-
+	// TODO: check that any declared content-length matches, like
+	// server.go's (*stream).endStream method.
 	rl.endStreamError(cs, nil)
 }
 
@@ -7074,7 +8324,7 @@
 	cc := rl.cc
 	cc.t.connPool().MarkDead(cc)
 	if f.ErrCode != 0 {
-
+		// TODO: deal with GOAWAY more. particularly the error code
 		cc.vlogf("transport got GOAWAY with error code = %v", f.ErrCode)
 	}
 	cc.setGoAway(f)
@@ -7101,11 +8351,17 @@
 		case http2SettingMaxConcurrentStreams:
 			cc.maxConcurrentStreams = s.Val
 		case http2SettingInitialWindowSize:
-
+			// Values above the maximum flow-control
+			// window size of 2^31-1 MUST be treated as a
+			// connection error (Section 5.4.1) of type
+			// FLOW_CONTROL_ERROR.
 			if s.Val > math.MaxInt32 {
 				return http2ConnectionError(http2ErrCodeFlowControl)
 			}
 
+			// Adjust flow control of currently-open
+			// frames by the difference of the old initial
+			// window size and this one.
 			delta := int32(s.Val) - int32(cc.initialWindowSize)
 			for _, cs := range cc.streams {
 				cs.flow.add(delta)
@@ -7114,7 +8370,7 @@
 
 			cc.initialWindowSize = s.Val
 		default:
-
+			// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
 			cc.vlogf("Unhandled Setting: %v", s)
 		}
 		return nil
@@ -7155,18 +8411,21 @@
 func (rl *http2clientConnReadLoop) processResetStream(f *http2RSTStreamFrame) error {
 	cs := rl.cc.streamByID(f.StreamID, true)
 	if cs == nil {
-
+		// TODO: return error if server tries to RST_STEAM an idle stream
 		return nil
 	}
 	select {
 	case <-cs.peerReset:
-
+		// Already reset.
+		// This is the only goroutine
+		// which closes this, so there
+		// isn't a race.
 	default:
 		err := http2streamError(cs.ID, f.ErrCode)
 		cs.resetErr = err
 		close(cs.peerReset)
 		cs.bufPipe.CloseWithError(err)
-		cs.cc.cond.Broadcast()
+		cs.cc.cond.Broadcast() // wake up checkResetOrDone via clientStream.awaitFlowControl
 	}
 	delete(rl.activeRes, cs.ID)
 	return nil
@@ -7183,7 +8442,7 @@
 			return err
 		}
 		cc.mu.Lock()
-
+		// check for dup before insert
 		if _, found := cc.pings[p]; !found {
 			cc.pings[p] = c
 			cc.mu.Unlock()
@@ -7207,7 +8466,7 @@
 	case <-ctx.Done():
 		return ctx.Err()
 	case <-cc.readerDone:
-
+		// connection closed
 		return cc.readerErr
 	}
 }
@@ -7217,7 +8476,7 @@
 		cc := rl.cc
 		cc.mu.Lock()
 		defer cc.mu.Unlock()
-
+		// If ack, notify listener if any
 		if c, ok := cc.pings[f.Data]; ok {
 			close(c)
 			delete(cc.pings, f.Data)
@@ -7234,12 +8493,21 @@
 }
 
 func (rl *http2clientConnReadLoop) processPushPromise(f *http2PushPromiseFrame) error {
-
+	// We told the peer we don't want them.
+	// Spec says:
+	// "PUSH_PROMISE MUST NOT be sent if the SETTINGS_ENABLE_PUSH
+	// setting of the peer endpoint is set to 0. An endpoint that
+	// has set this setting and has received acknowledgement MUST
+	// treat the receipt of a PUSH_PROMISE frame as a connection
+	// error (Section 5.4.1) of type PROTOCOL_ERROR."
 	return http2ConnectionError(http2ErrCodeProtocol)
 }
 
 func (cc *http2ClientConn) writeStreamReset(streamID uint32, code http2ErrCode, err error) {
-
+	// TODO: map err to more interesting error codes, once the
+	// HTTP community comes up with some. But currently for
+	// RST_STREAM there's no equivalent to GOAWAY frame's debug
+	// data, and the error codes are all pretty vague ("cancel").
 	cc.wmu.Lock()
 	cc.fr.WriteRSTStream(streamID, code)
 	cc.bw.Flush()
@@ -7368,7 +8636,8 @@
 
 func (s http2bodyWriterState) on100() {
 	if s.timer == nil {
-
+		// If we didn't do a delayed write, ignore the server's
+		// bogus 100 continue response.
 		return
 	}
 	s.timer.Stop()
@@ -7380,7 +8649,9 @@
 // called until after the headers have been written.
 func (s http2bodyWriterState) scheduleBodyWrite() {
 	if s.timer == nil {
-
+		// We're not doing a delayed write (see
+		// getBodyWriterState), so just start the writing
+		// goroutine immediately.
 		go s.fn()
 		return
 	}
@@ -7435,7 +8706,9 @@
 	case *http2writeResHeaders:
 		return v.endStream
 	case nil:
-
+		// This can only happen if the caller reuses w after it's
+		// been intentionally nil'ed out to prevent use. Keep this
+		// here to catch future refactoring breaking it.
 		panic("writeEndsStream called on nil writeFramer")
 	}
 	return false
@@ -7469,14 +8742,14 @@
 func (p *http2writeGoAway) writeFrame(ctx http2writeContext) error {
 	err := ctx.Framer().WriteGoAway(p.maxStreamID, p.code, nil)
 	if p.code != 0 {
-		ctx.Flush()
+		ctx.Flush() // ignore error: we're hanging up on them anyway
 		time.Sleep(50 * time.Millisecond)
 		ctx.CloseConn()
 	}
 	return err
 }
 
-func (*http2writeGoAway) staysWithinBuffer(max int) bool { return false }
+func (*http2writeGoAway) staysWithinBuffer(max int) bool { return false } // flushes
 
 type http2writeData struct {
 	streamID  uint32
@@ -7581,7 +8854,13 @@
 }
 
 func (w *http2writeResHeaders) staysWithinBuffer(max int) bool {
-
+	// TODO: this is a common one. It'd be nice to return true
+	// here and get into the fast path if we could be clever and
+	// calculate the size fast enough, or at least a conservative
+	// uppper bound that usually fires. (Maybe if w.h and
+	// w.trailers are nil, so we don't need to enumerate it.)
+	// Otherwise I'm afraid that just calculating the length to
+	// answer this question would be slower than the ~2µs benefit.
 	return false
 }
 
@@ -7640,7 +8919,7 @@
 }
 
 func (w *http2writePushPromise) staysWithinBuffer(max int) bool {
-
+	// TODO: see writeResHeaders.staysWithinBuffer
 	return false
 }
 
@@ -7692,7 +8971,7 @@
 }
 
 func (w http2write100ContinueHeadersFrame) staysWithinBuffer(max int) bool {
-
+	// Sloppy but conservative:
 	return 9+2*(len(":status")+len("100")) <= max
 }
 
@@ -7712,7 +8991,9 @@
 func http2encodeHeaders(enc *hpack.Encoder, h Header, keys []string) {
 	if keys == nil {
 		sorter := http2sorterPool.Get().(*http2sorter)
-
+		// Using defer here, since the returned keys from the
+		// sorter.Keys method is only valid until the sorter
+		// is returned:
 		defer http2sorterPool.Put(sorter)
 		keys = sorter.Keys(h)
 	}
@@ -7720,16 +9001,19 @@
 		vv := h[k]
 		k = http2lowerHeader(k)
 		if !http2validWireHeaderFieldName(k) {
-
+			// Skip it as backup paranoia. Per
+			// golang.org/issue/14048, these should
+			// already be rejected at a higher level.
 			continue
 		}
 		isTE := k == "transfer-encoding"
 		for _, v := range vv {
 			if !httplex.ValidHeaderFieldValue(v) {
-
+				// TODO: return an error? golang.org/issue/14048
+				// For now just omit it.
 				continue
 			}
-
+			// TODO: more of "8.1.2.2 Connection-Specific Header Fields"
 			if isTE && v != "trailers" {
 				continue
 			}
@@ -7797,7 +9081,10 @@
 func (wr http2FrameWriteRequest) StreamID() uint32 {
 	if wr.stream == nil {
 		if se, ok := wr.write.(http2StreamError); ok {
-
+			// (*serverConn).resetStream doesn't set
+			// stream because it doesn't necessarily have
+			// one. So special case this type of write
+			// message.
 			return se.StreamID
 		}
 		return 0
@@ -7827,11 +9114,13 @@
 func (wr http2FrameWriteRequest) Consume(n int32) (http2FrameWriteRequest, http2FrameWriteRequest, int) {
 	var empty http2FrameWriteRequest
 
+	// Non-DATA frames are always consumed whole.
 	wd, ok := wr.write.(*http2writeData)
 	if !ok || len(wd.p) == 0 {
 		return wr, empty, 1
 	}
 
+	// Might need to split after applying limits.
 	allowed := wr.stream.flow.available()
 	if n < allowed {
 		allowed = n
@@ -7849,10 +9138,13 @@
 			write: &http2writeData{
 				streamID: wd.streamID,
 				p:        wd.p[:allowed],
-
+				// Even if the original had endStream set, there
+				// are bytes remaining because len(wd.p) > allowed,
+				// so we know endStream is false.
 				endStream: false,
 			},
-
+			// Our caller is blocking on the final DATA frame, not
+			// this intermediate frame, so no need to wait.
 			done: nil,
 		}
 		rest := http2FrameWriteRequest{
@@ -7867,6 +9159,8 @@
 		return consumed, rest, 2
 	}
 
+	// The frame is consumed whole.
+	// NB: This cast cannot overflow because allowed is <= math.MaxInt32.
 	wr.stream.flow.take(int32(len(wd.p)))
 	return wr, empty, 1
 }
@@ -7893,7 +9187,7 @@
 	default:
 		panic(fmt.Sprintf("unbuffered done channel passed in for type %T", wr.write))
 	}
-	wr.write = nil
+	wr.write = nil // prevent use (assume it's tainted after wr.done send)
 }
 
 // writeQueue is used by implementations of WriteScheduler.
@@ -7912,7 +9206,7 @@
 		panic("invalid use of queue")
 	}
 	wr := q.s[0]
-
+	// TODO: less copy-happy queue.
 	copy(q.s, q.s[1:])
 	q.s[len(q.s)-1] = http2FrameWriteRequest{}
 	q.s = q.s[:len(q.s)-1]
@@ -7942,6 +9236,8 @@
 type http2writeQueuePool []*http2writeQueue
 
 // put inserts an unused writeQueue into the pool.
+
+// put inserts an unused writeQueue into the pool.
 func (p *http2writeQueuePool) put(q *http2writeQueue) {
 	for i := range q.s {
 		q.s[i] = http2FrameWriteRequest{}
@@ -8006,11 +9302,12 @@
 }
 
 // NewPriorityWriteScheduler constructs a WriteScheduler that schedules
-// frames by following HTTP/2 priorities as described in RFC 7340 Section 5.3.
+// frames by following HTTP/2 priorities as described in RFC 7540 Section 5.3.
 // If cfg is nil, default options are used.
 func http2NewPriorityWriteScheduler(cfg *http2PriorityWriteSchedulerConfig) http2WriteScheduler {
 	if cfg == nil {
-
+		// For justification of these defaults, see:
+		// https://docs.google.com/document/d/1oLhNg1skaWD4_DtaoCxdSRN5erEXrH-KnLrMwEpOtFY
 		cfg = &http2PriorityWriteSchedulerConfig{
 			MaxClosedNodesInTree:     10,
 			MaxIdleNodesInTree:       10,
@@ -8065,7 +9362,7 @@
 	if n.parent == parent {
 		return
 	}
-
+	// Unlink from current parent.
 	if parent := n.parent; parent != nil {
 		if n.prev == nil {
 			parent.kids = n.next
@@ -8076,7 +9373,9 @@
 			n.next.prev = n.prev
 		}
 	}
-
+	// Link to new parent.
+	// If parent=nil, remove n from the tree.
+	// Always insert at the head of parent.kids (this is assumed by walkReadyInOrder).
 	n.parent = parent
 	if parent == nil {
 		n.next = nil
@@ -8112,10 +9411,15 @@
 		return false
 	}
 
+	// Don't consider the root "open" when updating openParent since
+	// we can't send data frames on the root stream (only control frames).
 	if n.id != 0 {
 		openParent = openParent || (n.state == http2priorityNodeOpen)
 	}
 
+	// Common case: only one kid or all kids have the same weight.
+	// Some clients don't use weights; other clients (like web browsers)
+	// use mostly-linear priority trees.
 	w := n.kids.weight
 	needSort := false
 	for k := n.kids.next; k != nil; k = k.next {
@@ -8133,6 +9437,8 @@
 		return false
 	}
 
+	// Uncommon case: sort the child nodes. We remove the kids from the parent,
+	// then re-insert after sorting so we can reuse tmp for future sort calls.
 	*tmp = (*tmp)[:0]
 	for n.kids != nil {
 		*tmp = append(*tmp, n.kids)
@@ -8140,7 +9446,7 @@
 	}
 	sort.Sort(http2sortPriorityNodeSiblings(*tmp))
 	for i := len(*tmp) - 1; i >= 0; i-- {
-		(*tmp)[i].setParent(n)
+		(*tmp)[i].setParent(n) // setParent inserts at the head of n.kids
 	}
 	for k := n.kids; k != nil; k = k.next {
 		if k.walkReadyInOrder(openParent, tmp, f) {
@@ -8157,7 +9463,8 @@
 func (z http2sortPriorityNodeSiblings) Swap(i, k int) { z[i], z[k] = z[k], z[i] }
 
 func (z http2sortPriorityNodeSiblings) Less(i, k int) bool {
-
+	// Prefer the subtree that has sent fewer bytes relative to its weight.
+	// See sections 5.3.2 and 5.3.4.
 	wi, bi := float64(z[i].weight+1), float64(z[i].subtreeBytes)
 	wk, bk := float64(z[k].weight+1), float64(z[k].subtreeBytes)
 	if bi == 0 && bk == 0 {
@@ -8199,7 +9506,7 @@
 }
 
 func (ws *http2priorityWriteScheduler) OpenStream(streamID uint32, options http2OpenStreamOptions) {
-
+	// The stream may be currently idle but cannot be opened or closed.
 	if curr := ws.nodes[streamID]; curr != nil {
 		if curr.state != http2priorityNodeIdle {
 			panic(fmt.Sprintf("stream %d already opened", streamID))
@@ -8208,6 +9515,10 @@
 		return
 	}
 
+	// RFC 7540, Section 5.3.5:
+	//  "All streams are initially assigned a non-exclusive dependency on stream 0x0.
+	//  Pushed streams initially depend on their associated stream. In both cases,
+	//  streams are assigned a default weight of 16."
 	parent := ws.nodes[options.PusherID]
 	if parent == nil {
 		parent = &ws.root
@@ -8255,6 +9566,9 @@
 		panic("adjustPriority on root")
 	}
 
+	// If streamID does not exist, there are two cases:
+	// - A closed stream that has been removed (this will have ID <= maxID)
+	// - An idle stream that is being used for "grouping" (this will have ID > maxID)
 	n := ws.nodes[streamID]
 	if n == nil {
 		if streamID <= ws.maxID || ws.maxIdleNodesInTree == 0 {
@@ -8272,6 +9586,8 @@
 		ws.addClosedOrIdleNode(&ws.idleNodes, ws.maxIdleNodesInTree, n)
 	}
 
+	// Section 5.3.1: A dependency on a stream that is not currently in the tree
+	// results in that stream being given a default priority (Section 5.3.5).
 	parent := ws.nodes[priority.StreamDep]
 	if parent == nil {
 		n.setParent(&ws.root)
@@ -8279,10 +9595,18 @@
 		return
 	}
 
+	// Ignore if the client tries to make a node its own parent.
 	if n == parent {
 		return
 	}
 
+	// Section 5.3.3:
+	//   "If a stream is made dependent on one of its own dependencies, the
+	//   formerly dependent stream is first moved to be dependent on the
+	//   reprioritized stream's previous parent. The moved dependency retains
+	//   its weight."
+	//
+	// That is: if parent depends on n, move parent to depend on n.parent.
 	for x := parent.parent; x != nil; x = x.parent {
 		if x == n {
 			parent.setParent(n.parent)
@@ -8290,6 +9614,9 @@
 		}
 	}
 
+	// Section 5.3.3: The exclusive flag causes the stream to become the sole
+	// dependency of its parent stream, causing other dependencies to become
+	// dependent on the exclusive stream.
 	if priority.Exclusive {
 		k := parent.kids
 		for k != nil {
@@ -8312,7 +9639,11 @@
 	} else {
 		n = ws.nodes[id]
 		if n == nil {
-
+			// id is an idle or closed stream. wr should not be a HEADERS or
+			// DATA frame. However, wr can be a RST_STREAM. In this case, we
+			// push wr onto the root, rather than creating a new priorityNode,
+			// since RST_STREAM is tiny and the stream's priority is unknown
+			// anyway. See issue #17919.
 			if wr.DataSize() > 0 {
 				panic("add DATA on non-open stream")
 			}
@@ -8333,7 +9664,9 @@
 			return false
 		}
 		n.addBytes(int64(wr.DataSize()))
-
+		// If B depends on A and B continuously has data available but A
+		// does not, gradually increase the throttling limit to allow B to
+		// steal more and more bandwidth from A.
 		if openParent {
 			ws.writeThrottleLimit += 1024
 			if ws.writeThrottleLimit < 0 {
@@ -8352,7 +9685,7 @@
 		return
 	}
 	if len(*list) == maxSize {
-
+		// Remove the oldest node, then shift left.
 		ws.removeNode((*list)[0])
 		x := (*list)[1:]
 		copy(*list, x)
@@ -8390,7 +9723,7 @@
 }
 
 func (ws *http2randomWriteScheduler) OpenStream(streamID uint32, options http2OpenStreamOptions) {
-
+	// no-op: idle streams are not tracked
 }
 
 func (ws *http2randomWriteScheduler) CloseStream(streamID uint32) {
@@ -8403,7 +9736,7 @@
 }
 
 func (ws *http2randomWriteScheduler) AdjustStream(streamID uint32, priority http2PriorityParam) {
-
+	// no-op: priorities are ignored
 }
 
 func (ws *http2randomWriteScheduler) Push(wr http2FrameWriteRequest) {
@@ -8421,11 +9754,11 @@
 }
 
 func (ws *http2randomWriteScheduler) Pop() (http2FrameWriteRequest, bool) {
-
+	// Control frames first.
 	if !ws.zero.empty() {
 		return ws.zero.shift(), true
 	}
-
+	// Iterate over all non-idle streams until finding one that can be consumed.
 	for _, q := range ws.sq {
 		if wr, ok := q.consume(math.MaxInt32); ok {
 			return wr, true
diff --git a/libgo/go/net/http/httptest/recorder.go b/libgo/go/net/http/httptest/recorder.go
index 5f1aa6a..741f076 100644
--- a/libgo/go/net/http/httptest/recorder.go
+++ b/libgo/go/net/http/httptest/recorder.go
@@ -6,6 +6,7 @@
 
 import (
 	"bytes"
+	"fmt"
 	"io/ioutil"
 	"net/http"
 	"strconv"
@@ -176,7 +177,7 @@
 	if res.StatusCode == 0 {
 		res.StatusCode = 200
 	}
-	res.Status = http.StatusText(res.StatusCode)
+	res.Status = fmt.Sprintf("%03d %s", res.StatusCode, http.StatusText(res.StatusCode))
 	if rw.Body != nil {
 		res.Body = ioutil.NopCloser(bytes.NewReader(rw.Body.Bytes()))
 	}
diff --git a/libgo/go/net/http/httptest/recorder_test.go b/libgo/go/net/http/httptest/recorder_test.go
index 9afba4e..a6259eb 100644
--- a/libgo/go/net/http/httptest/recorder_test.go
+++ b/libgo/go/net/http/httptest/recorder_test.go
@@ -23,7 +23,15 @@
 			return nil
 		}
 	}
-	hasResultStatus := func(wantCode int) checkFunc {
+	hasResultStatus := func(want string) checkFunc {
+		return func(rec *ResponseRecorder) error {
+			if rec.Result().Status != want {
+				return fmt.Errorf("Result().Status = %q; want %q", rec.Result().Status, want)
+			}
+			return nil
+		}
+	}
+	hasResultStatusCode := func(wantCode int) checkFunc {
 		return func(rec *ResponseRecorder) error {
 			if rec.Result().StatusCode != wantCode {
 				return fmt.Errorf("Result().StatusCode = %d; want %d", rec.Result().StatusCode, wantCode)
@@ -235,7 +243,8 @@
 				hasOldHeader("X-Foo", "1"),
 				hasStatus(0),
 				hasHeader("X-Foo", "1"),
-				hasResultStatus(200),
+				hasResultStatus("200 OK"),
+				hasResultStatusCode(200),
 			),
 		},
 		{
diff --git a/libgo/go/net/http/httptest/server.go b/libgo/go/net/http/httptest/server.go
index 5e9ace5..e543672 100644
--- a/libgo/go/net/http/httptest/server.go
+++ b/libgo/go/net/http/httptest/server.go
@@ -9,6 +9,7 @@
 import (
 	"bytes"
 	"crypto/tls"
+	"crypto/x509"
 	"flag"
 	"fmt"
 	"log"
@@ -35,6 +36,9 @@
 	// before Start or StartTLS.
 	Config *http.Server
 
+	// certificate is a parsed version of the TLS config certificate, if present.
+	certificate *x509.Certificate
+
 	// wg counts the number of outstanding HTTP requests on this server.
 	// Close blocks until all requests are finished.
 	wg sync.WaitGroup
@@ -42,6 +46,10 @@
 	mu     sync.Mutex // guards closed and conns
 	closed bool
 	conns  map[net.Conn]http.ConnState // except terminal states
+
+	// client is configured for use with the server.
+	// Its transport is automatically closed when Close is called.
+	client *http.Client
 }
 
 func newLocalListener() net.Listener {
@@ -93,6 +101,9 @@
 	if s.URL != "" {
 		panic("Server already started")
 	}
+	if s.client == nil {
+		s.client = &http.Client{Transport: &http.Transport{}}
+	}
 	s.URL = "http://" + s.Listener.Addr().String()
 	s.wrap()
 	s.goServe()
@@ -107,6 +118,9 @@
 	if s.URL != "" {
 		panic("Server already started")
 	}
+	if s.client == nil {
+		s.client = &http.Client{Transport: &http.Transport{}}
+	}
 	cert, err := tls.X509KeyPair(internal.LocalhostCert, internal.LocalhostKey)
 	if err != nil {
 		panic(fmt.Sprintf("httptest: NewTLSServer: %v", err))
@@ -124,6 +138,17 @@
 	if len(s.TLS.Certificates) == 0 {
 		s.TLS.Certificates = []tls.Certificate{cert}
 	}
+	s.certificate, err = x509.ParseCertificate(s.TLS.Certificates[0].Certificate[0])
+	if err != nil {
+		panic(fmt.Sprintf("httptest: NewTLSServer: %v", err))
+	}
+	certpool := x509.NewCertPool()
+	certpool.AddCert(s.certificate)
+	s.client.Transport = &http.Transport{
+		TLSClientConfig: &tls.Config{
+			RootCAs: certpool,
+		},
+	}
 	s.Listener = tls.NewListener(s.Listener, s.TLS)
 	s.URL = "https://" + s.Listener.Addr().String()
 	s.wrap()
@@ -186,6 +211,13 @@
 		t.CloseIdleConnections()
 	}
 
+	// Also close the client idle connections.
+	if s.client != nil {
+		if t, ok := s.client.Transport.(closeIdleTransport); ok {
+			t.CloseIdleConnections()
+		}
+	}
+
 	s.wg.Wait()
 }
 
@@ -206,7 +238,7 @@
 	nconn := len(s.conns)
 	ch := make(chan struct{}, nconn)
 	for c := range s.conns {
-		s.closeConnChan(c, ch)
+		go s.closeConnChan(c, ch)
 	}
 	s.mu.Unlock()
 
@@ -228,6 +260,19 @@
 	}
 }
 
+// Certificate returns the certificate used by the server, or nil if
+// the server doesn't use TLS.
+func (s *Server) Certificate() *x509.Certificate {
+	return s.certificate
+}
+
+// Client returns an HTTP client configured for making requests to the server.
+// It is configured to trust the server's TLS test certificate and will
+// close its idle connections on Server.Close.
+func (s *Server) Client() *http.Client {
+	return s.client
+}
+
 func (s *Server) goServe() {
 	s.wg.Add(1)
 	go func() {
diff --git a/libgo/go/net/http/httptest/server_test.go b/libgo/go/net/http/httptest/server_test.go
index d032c59..8ab50cd 100644
--- a/libgo/go/net/http/httptest/server_test.go
+++ b/libgo/go/net/http/httptest/server_test.go
@@ -12,8 +12,48 @@
 	"testing"
 )
 
+type newServerFunc func(http.Handler) *Server
+
+var newServers = map[string]newServerFunc{
+	"NewServer":    NewServer,
+	"NewTLSServer": NewTLSServer,
+
+	// The manual variants of newServer create a Server manually by only filling
+	// in the exported fields of Server.
+	"NewServerManual": func(h http.Handler) *Server {
+		ts := &Server{Listener: newLocalListener(), Config: &http.Server{Handler: h}}
+		ts.Start()
+		return ts
+	},
+	"NewTLSServerManual": func(h http.Handler) *Server {
+		ts := &Server{Listener: newLocalListener(), Config: &http.Server{Handler: h}}
+		ts.StartTLS()
+		return ts
+	},
+}
+
 func TestServer(t *testing.T) {
-	ts := NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	for _, name := range []string{"NewServer", "NewServerManual"} {
+		t.Run(name, func(t *testing.T) {
+			newServer := newServers[name]
+			t.Run("Server", func(t *testing.T) { testServer(t, newServer) })
+			t.Run("GetAfterClose", func(t *testing.T) { testGetAfterClose(t, newServer) })
+			t.Run("ServerCloseBlocking", func(t *testing.T) { testServerCloseBlocking(t, newServer) })
+			t.Run("ServerCloseClientConnections", func(t *testing.T) { testServerCloseClientConnections(t, newServer) })
+			t.Run("ServerClientTransportType", func(t *testing.T) { testServerClientTransportType(t, newServer) })
+		})
+	}
+	for _, name := range []string{"NewTLSServer", "NewTLSServerManual"} {
+		t.Run(name, func(t *testing.T) {
+			newServer := newServers[name]
+			t.Run("ServerClient", func(t *testing.T) { testServerClient(t, newServer) })
+			t.Run("TLSServerClientTransportType", func(t *testing.T) { testTLSServerClientTransportType(t, newServer) })
+		})
+	}
+}
+
+func testServer(t *testing.T, newServer newServerFunc) {
+	ts := newServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte("hello"))
 	}))
 	defer ts.Close()
@@ -22,6 +62,7 @@
 		t.Fatal(err)
 	}
 	got, err := ioutil.ReadAll(res.Body)
+	res.Body.Close()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -31,8 +72,8 @@
 }
 
 // Issue 12781
-func TestGetAfterClose(t *testing.T) {
-	ts := NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+func testGetAfterClose(t *testing.T, newServer newServerFunc) {
+	ts := newServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte("hello"))
 	}))
 
@@ -57,8 +98,8 @@
 	}
 }
 
-func TestServerCloseBlocking(t *testing.T) {
-	ts := NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+func testServerCloseBlocking(t *testing.T, newServer newServerFunc) {
+	ts := newServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte("hello"))
 	}))
 	dial := func() net.Conn {
@@ -86,9 +127,9 @@
 }
 
 // Issue 14290
-func TestServerCloseClientConnections(t *testing.T) {
+func testServerCloseClientConnections(t *testing.T, newServer newServerFunc) {
 	var s *Server
-	s = NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	s = newServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		s.CloseClientConnections()
 	}))
 	defer s.Close()
@@ -98,3 +139,66 @@
 		t.Fatalf("Unexpected response: %#v", res)
 	}
 }
+
+// Tests that the Server.Client method works and returns an http.Client that can hit
+// NewTLSServer without cert warnings.
+func testServerClient(t *testing.T, newTLSServer newServerFunc) {
+	ts := newTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte("hello"))
+	}))
+	defer ts.Close()
+	client := ts.Client()
+	res, err := client.Get(ts.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got, err := ioutil.ReadAll(res.Body)
+	res.Body.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(got) != "hello" {
+		t.Errorf("got %q, want hello", string(got))
+	}
+}
+
+// Tests that the Server.Client.Transport interface is implemented
+// by a *http.Transport.
+func testServerClientTransportType(t *testing.T, newServer newServerFunc) {
+	ts := newServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	}))
+	defer ts.Close()
+	client := ts.Client()
+	if _, ok := client.Transport.(*http.Transport); !ok {
+		t.Errorf("got %T, want *http.Transport", client.Transport)
+	}
+}
+
+// Tests that the TLS Server.Client.Transport interface is implemented
+// by a *http.Transport.
+func testTLSServerClientTransportType(t *testing.T, newTLSServer newServerFunc) {
+	ts := newTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	}))
+	defer ts.Close()
+	client := ts.Client()
+	if _, ok := client.Transport.(*http.Transport); !ok {
+		t.Errorf("got %T, want *http.Transport", client.Transport)
+	}
+}
+
+type onlyCloseListener struct {
+	net.Listener
+}
+
+func (onlyCloseListener) Close() error { return nil }
+
+// Issue 19729: panic in Server.Close for values created directly
+// without a constructor (so the unexported client field is nil).
+func TestServerZeroValueClose(t *testing.T) {
+	ts := &Server{
+		Listener: onlyCloseListener{},
+		Config:   &http.Server{},
+	}
+
+	ts.Close() // tests that it doesn't panic
+}
diff --git a/libgo/go/net/http/httputil/reverseproxy.go b/libgo/go/net/http/httputil/reverseproxy.go
index 79c8fe2..0d514f5 100644
--- a/libgo/go/net/http/httputil/reverseproxy.go
+++ b/libgo/go/net/http/httputil/reverseproxy.go
@@ -114,6 +114,16 @@
 	}
 }
 
+func cloneHeader(h http.Header) http.Header {
+	h2 := make(http.Header, len(h))
+	for k, vv := range h {
+		vv2 := make([]string, len(vv))
+		copy(vv2, vv)
+		h2[k] = vv2
+	}
+	return h2
+}
+
 // Hop-by-hop headers. These are removed when sent to the backend.
 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html
 var hopHeaders = []string{
@@ -149,30 +159,21 @@
 		}()
 	}
 
-	outreq := new(http.Request)
-	*outreq = *req // includes shallow copies of maps, but okay
+	outreq := req.WithContext(ctx) // includes shallow copies of maps, but okay
 	if req.ContentLength == 0 {
 		outreq.Body = nil // Issue 16036: nil Body for http.Transport retries
 	}
-	outreq = outreq.WithContext(ctx)
+
+	outreq.Header = cloneHeader(req.Header)
 
 	p.Director(outreq)
 	outreq.Close = false
 
-	// We are modifying the same underlying map from req (shallow
-	// copied above) so we only copy it if necessary.
-	copiedHeaders := false
-
 	// Remove hop-by-hop headers listed in the "Connection" header.
 	// See RFC 2616, section 14.10.
 	if c := outreq.Header.Get("Connection"); c != "" {
 		for _, f := range strings.Split(c, ",") {
 			if f = strings.TrimSpace(f); f != "" {
-				if !copiedHeaders {
-					outreq.Header = make(http.Header)
-					copyHeader(outreq.Header, req.Header)
-					copiedHeaders = true
-				}
 				outreq.Header.Del(f)
 			}
 		}
@@ -183,11 +184,6 @@
 	// connection, regardless of what the client sent to us.
 	for _, h := range hopHeaders {
 		if outreq.Header.Get(h) != "" {
-			if !copiedHeaders {
-				outreq.Header = make(http.Header)
-				copyHeader(outreq.Header, req.Header)
-				copiedHeaders = true
-			}
 			outreq.Header.Del(h)
 		}
 	}
@@ -235,7 +231,8 @@
 
 	// The "Trailer" header isn't included in the Transport's response,
 	// at least for *http.Transport. Build it up from Trailer.
-	if len(res.Trailer) > 0 {
+	announcedTrailers := len(res.Trailer)
+	if announcedTrailers > 0 {
 		trailerKeys := make([]string, 0, len(res.Trailer))
 		for k := range res.Trailer {
 			trailerKeys = append(trailerKeys, k)
@@ -254,7 +251,18 @@
 	}
 	p.copyResponse(rw, res.Body)
 	res.Body.Close() // close now, instead of defer, to populate res.Trailer
-	copyHeader(rw.Header(), res.Trailer)
+
+	if len(res.Trailer) == announcedTrailers {
+		copyHeader(rw.Header(), res.Trailer)
+		return
+	}
+
+	for k, vv := range res.Trailer {
+		k = http.TrailerPrefix + k
+		for _, v := range vv {
+			rw.Header().Add(k, v)
+		}
+	}
 }
 
 func (p *ReverseProxy) copyResponse(dst io.Writer, src io.Reader) {
@@ -288,7 +296,7 @@
 	var written int64
 	for {
 		nr, rerr := src.Read(buf)
-		if rerr != nil && rerr != io.EOF {
+		if rerr != nil && rerr != io.EOF && rerr != context.Canceled {
 			p.logf("httputil: ReverseProxy read error during body copy: %v", rerr)
 		}
 		if nr > 0 {
diff --git a/libgo/go/net/http/httputil/reverseproxy_test.go b/libgo/go/net/http/httputil/reverseproxy_test.go
index 20c4e16..37a9992 100644
--- a/libgo/go/net/http/httputil/reverseproxy_test.go
+++ b/libgo/go/net/http/httputil/reverseproxy_test.go
@@ -69,6 +69,7 @@
 		w.WriteHeader(backendStatus)
 		w.Write([]byte(backendResponse))
 		w.Header().Set("X-Trailer", "trailer_value")
+		w.Header().Set(http.TrailerPrefix+"X-Unannounced-Trailer", "unannounced_trailer_value")
 	}))
 	defer backend.Close()
 	backendURL, err := url.Parse(backend.URL)
@@ -79,6 +80,7 @@
 	proxyHandler.ErrorLog = log.New(ioutil.Discard, "", 0) // quiet for tests
 	frontend := httptest.NewServer(proxyHandler)
 	defer frontend.Close()
+	frontendClient := frontend.Client()
 
 	getReq, _ := http.NewRequest("GET", frontend.URL, nil)
 	getReq.Host = "some-name"
@@ -86,7 +88,7 @@
 	getReq.Header.Set("Proxy-Connection", "should be deleted")
 	getReq.Header.Set("Upgrade", "foo")
 	getReq.Close = true
-	res, err := http.DefaultClient.Do(getReq)
+	res, err := frontendClient.Do(getReq)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -121,12 +123,15 @@
 	if g, e := res.Trailer.Get("X-Trailer"), "trailer_value"; g != e {
 		t.Errorf("Trailer(X-Trailer) = %q ; want %q", g, e)
 	}
+	if g, e := res.Trailer.Get("X-Unannounced-Trailer"), "unannounced_trailer_value"; g != e {
+		t.Errorf("Trailer(X-Unannounced-Trailer) = %q ; want %q", g, e)
+	}
 
 	// Test that a backend failing to be reached or one which doesn't return
 	// a response results in a StatusBadGateway.
 	getReq, _ = http.NewRequest("GET", frontend.URL+"/?mode=hangup", nil)
 	getReq.Close = true
-	res, err = http.DefaultClient.Do(getReq)
+	res, err = frontendClient.Do(getReq)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -172,7 +177,7 @@
 	getReq.Header.Set("Connection", "Upgrade, "+fakeConnectionToken)
 	getReq.Header.Set("Upgrade", "original value")
 	getReq.Header.Set(fakeConnectionToken, "should be deleted")
-	res, err := http.DefaultClient.Do(getReq)
+	res, err := frontend.Client().Do(getReq)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -220,7 +225,7 @@
 	getReq.Header.Set("Connection", "close")
 	getReq.Header.Set("X-Forwarded-For", prevForwardedFor)
 	getReq.Close = true
-	res, err := http.DefaultClient.Do(getReq)
+	res, err := frontend.Client().Do(getReq)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -259,7 +264,7 @@
 		frontend := httptest.NewServer(NewSingleHostReverseProxy(backendURL))
 		req, _ := http.NewRequest("GET", frontend.URL+tt.reqSuffix, nil)
 		req.Close = true
-		res, err := http.DefaultClient.Do(req)
+		res, err := frontend.Client().Do(req)
 		if err != nil {
 			t.Fatalf("%d. Get: %v", i, err)
 		}
@@ -295,7 +300,7 @@
 
 	req, _ := http.NewRequest("GET", frontend.URL, nil)
 	req.Close = true
-	res, err := http.DefaultClient.Do(req)
+	res, err := frontend.Client().Do(req)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -349,13 +354,14 @@
 
 	frontend := httptest.NewServer(proxyHandler)
 	defer frontend.Close()
+	frontendClient := frontend.Client()
 
 	getReq, _ := http.NewRequest("GET", frontend.URL, nil)
 	go func() {
 		<-reqInFlight
-		http.DefaultTransport.(*http.Transport).CancelRequest(getReq)
+		frontendClient.Transport.(*http.Transport).CancelRequest(getReq)
 	}()
-	res, err := http.DefaultClient.Do(getReq)
+	res, err := frontendClient.Do(getReq)
 	if res != nil {
 		t.Errorf("got response %v; want nil", res.Status)
 	}
@@ -363,7 +369,7 @@
 		// This should be an error like:
 		// Get http://127.0.0.1:58079: read tcp 127.0.0.1:58079:
 		//    use of closed network connection
-		t.Error("DefaultClient.Do() returned nil error; want non-nil error")
+		t.Error("Server.Client().Do() returned nil error; want non-nil error")
 	}
 }
 
@@ -428,11 +434,12 @@
 	proxyHandler.ErrorLog = log.New(ioutil.Discard, "", 0) // quiet for tests
 	frontend := httptest.NewServer(proxyHandler)
 	defer frontend.Close()
+	frontendClient := frontend.Client()
 
 	getReq, _ := http.NewRequest("GET", frontend.URL, nil)
 	getReq.Header.Set("User-Agent", explicitUA)
 	getReq.Close = true
-	res, err := http.DefaultClient.Do(getReq)
+	res, err := frontendClient.Do(getReq)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -441,7 +448,7 @@
 	getReq, _ = http.NewRequest("GET", frontend.URL+"/noua", nil)
 	getReq.Header.Set("User-Agent", "")
 	getReq.Close = true
-	res, err = http.DefaultClient.Do(getReq)
+	res, err = frontendClient.Do(getReq)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -493,7 +500,7 @@
 
 	req, _ := http.NewRequest("GET", frontend.URL, nil)
 	req.Close = true
-	res, err := http.DefaultClient.Do(req)
+	res, err := frontend.Client().Do(req)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -540,7 +547,7 @@
 	defer frontend.Close()
 
 	postReq, _ := http.NewRequest("POST", frontend.URL, bytes.NewReader(requestBody))
-	res, err := http.DefaultClient.Do(postReq)
+	res, err := frontend.Client().Do(postReq)
 	if err != nil {
 		t.Fatalf("Do: %v", err)
 	}
@@ -573,7 +580,7 @@
 	frontend := httptest.NewServer(proxyHandler)
 	defer frontend.Close()
 
-	res, err := http.DefaultClient.Get(frontend.URL)
+	res, err := frontend.Client().Get(frontend.URL)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -664,3 +671,101 @@
 		}
 	}
 }
+
+type staticTransport struct {
+	res *http.Response
+}
+
+func (t *staticTransport) RoundTrip(r *http.Request) (*http.Response, error) {
+	return t.res, nil
+}
+
+func BenchmarkServeHTTP(b *testing.B) {
+	res := &http.Response{
+		StatusCode: 200,
+		Body:       ioutil.NopCloser(strings.NewReader("")),
+	}
+	proxy := &ReverseProxy{
+		Director:  func(*http.Request) {},
+		Transport: &staticTransport{res},
+	}
+
+	w := httptest.NewRecorder()
+	r := httptest.NewRequest("GET", "/", nil)
+
+	b.ReportAllocs()
+	for i := 0; i < b.N; i++ {
+		proxy.ServeHTTP(w, r)
+	}
+}
+
+func TestServeHTTPDeepCopy(t *testing.T) {
+	backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte("Hello Gopher!"))
+	}))
+	defer backend.Close()
+	backendURL, err := url.Parse(backend.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	type result struct {
+		before, after string
+	}
+
+	resultChan := make(chan result, 1)
+	proxyHandler := NewSingleHostReverseProxy(backendURL)
+	frontend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		before := r.URL.String()
+		proxyHandler.ServeHTTP(w, r)
+		after := r.URL.String()
+		resultChan <- result{before: before, after: after}
+	}))
+	defer frontend.Close()
+
+	want := result{before: "/", after: "/"}
+
+	res, err := frontend.Client().Get(frontend.URL)
+	if err != nil {
+		t.Fatalf("Do: %v", err)
+	}
+	res.Body.Close()
+
+	got := <-resultChan
+	if got != want {
+		t.Errorf("got = %+v; want = %+v", got, want)
+	}
+}
+
+// Issue 18327: verify we always do a deep copy of the Request.Header map
+// before any mutations.
+func TestClonesRequestHeaders(t *testing.T) {
+	req, _ := http.NewRequest("GET", "http://foo.tld/", nil)
+	req.RemoteAddr = "1.2.3.4:56789"
+	rp := &ReverseProxy{
+		Director: func(req *http.Request) {
+			req.Header.Set("From-Director", "1")
+		},
+		Transport: roundTripperFunc(func(req *http.Request) (*http.Response, error) {
+			if v := req.Header.Get("From-Director"); v != "1" {
+				t.Errorf("From-Directory value = %q; want 1", v)
+			}
+			return nil, io.EOF
+		}),
+	}
+	rp.ServeHTTP(httptest.NewRecorder(), req)
+
+	if req.Header.Get("From-Director") == "1" {
+		t.Error("Director header mutation modified caller's request")
+	}
+	if req.Header.Get("X-Forwarded-For") != "" {
+		t.Error("X-Forward-For header mutation modified caller's request")
+	}
+
+}
+
+type roundTripperFunc func(req *http.Request) (*http.Response, error)
+
+func (fn roundTripperFunc) RoundTrip(req *http.Request) (*http.Response, error) {
+	return fn(req)
+}
diff --git a/libgo/go/net/http/main_test.go b/libgo/go/net/http/main_test.go
index 438bd2e..21c8505 100644
--- a/libgo/go/net/http/main_test.go
+++ b/libgo/go/net/http/main_test.go
@@ -37,6 +37,8 @@
 		}
 		stack := strings.TrimSpace(sl[1])
 		if stack == "" ||
+			strings.Contains(stack, "testing.(*M).before.func1") ||
+			strings.Contains(stack, "os/signal.signal_recv") ||
 			strings.Contains(stack, "created by net.startServer") ||
 			strings.Contains(stack, "created by testing.RunTests") ||
 			strings.Contains(stack, "closeWriteAndWait") ||
@@ -56,8 +58,9 @@
 
 // Verify the other tests didn't leave any goroutines running.
 func goroutineLeaked() bool {
-	if testing.Short() {
-		// not counting goroutines for leakage in -short mode
+	if testing.Short() || runningBenchmarks() {
+		// Don't worry about goroutine leaks in -short mode or in
+		// benchmark mode. Too distracting when there are false positives.
 		return false
 	}
 
@@ -92,6 +95,18 @@
 	}
 }
 
+func runningBenchmarks() bool {
+	for i, arg := range os.Args {
+		if strings.HasPrefix(arg, "-test.bench=") && !strings.HasSuffix(arg, "=") {
+			return true
+		}
+		if arg == "-test.bench" && i < len(os.Args)-1 && os.Args[i+1] != "" {
+			return true
+		}
+	}
+	return false
+}
+
 func afterTest(t testing.TB) {
 	http.DefaultTransport.(*http.Transport).CloseIdleConnections()
 	if testing.Short() {
@@ -151,7 +166,3 @@
 	}
 	return err
 }
-
-func closeClient(c *http.Client) {
-	c.Transport.(*http.Transport).CloseIdleConnections()
-}
diff --git a/libgo/go/net/http/npn_test.go b/libgo/go/net/http/npn_test.go
index 4c1f6b5..618bdbe 100644
--- a/libgo/go/net/http/npn_test.go
+++ b/libgo/go/net/http/npn_test.go
@@ -8,6 +8,7 @@
 	"bufio"
 	"bytes"
 	"crypto/tls"
+	"crypto/x509"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -43,10 +44,7 @@
 
 	// Normal request, without NPN.
 	{
-		tr := newTLSTransport(t, ts)
-		defer tr.CloseIdleConnections()
-		c := &Client{Transport: tr}
-
+		c := ts.Client()
 		res, err := c.Get(ts.URL)
 		if err != nil {
 			t.Fatal(err)
@@ -63,11 +61,18 @@
 	// Request to an advertised but unhandled NPN protocol.
 	// Server will hang up.
 	{
-		tr := newTLSTransport(t, ts)
-		tr.TLSClientConfig.NextProtos = []string{"unhandled-proto"}
+		certPool := x509.NewCertPool()
+		certPool.AddCert(ts.Certificate())
+		tr := &Transport{
+			TLSClientConfig: &tls.Config{
+				RootCAs:    certPool,
+				NextProtos: []string{"unhandled-proto"},
+			},
+		}
 		defer tr.CloseIdleConnections()
-		c := &Client{Transport: tr}
-
+		c := &Client{
+			Transport: tr,
+		}
 		res, err := c.Get(ts.URL)
 		if err == nil {
 			defer res.Body.Close()
@@ -80,7 +85,8 @@
 	// Request using the "tls-0.9" protocol, which we register here.
 	// It is HTTP/0.9 over TLS.
 	{
-		tlsConfig := newTLSTransport(t, ts).TLSClientConfig
+		c := ts.Client()
+		tlsConfig := c.Transport.(*Transport).TLSClientConfig
 		tlsConfig.NextProtos = []string{"tls-0.9"}
 		conn, err := tls.Dial("tcp", ts.Listener.Addr().String(), tlsConfig)
 		if err != nil {
diff --git a/libgo/go/net/http/pprof/pprof.go b/libgo/go/net/http/pprof/pprof.go
index 05d0890..12c7599 100644
--- a/libgo/go/net/http/pprof/pprof.go
+++ b/libgo/go/net/http/pprof/pprof.go
@@ -37,6 +37,11 @@
 //
 //	wget http://localhost:6060/debug/pprof/trace?seconds=5
 //
+// Or to look at the holders of contended mutexes, after calling
+// runtime.SetMutexProfileFraction in your program:
+//
+//	go tool pprof http://localhost:6060/debug/pprof/mutex
+//
 // To view all available profiles, open http://localhost:6060/debug/pprof/
 // in your browser.
 //
@@ -57,6 +62,7 @@
 	"os"
 	"runtime"
 	"runtime/pprof"
+	"runtime/trace"
 	"strconv"
 	"strings"
 	"time"
@@ -89,6 +95,11 @@
 	}
 }
 
+func durationExceedsWriteTimeout(r *http.Request, seconds float64) bool {
+	srv, ok := r.Context().Value(http.ServerContextKey).(*http.Server)
+	return ok && srv.WriteTimeout != 0 && seconds >= srv.WriteTimeout.Seconds()
+}
+
 // Profile responds with the pprof-formatted cpu profile.
 // The package initialization registers it as /debug/pprof/profile.
 func Profile(w http.ResponseWriter, r *http.Request) {
@@ -97,6 +108,14 @@
 		sec = 30
 	}
 
+	if durationExceedsWriteTimeout(r, float64(sec)) {
+		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+		w.Header().Set("X-Go-Pprof", "1")
+		w.WriteHeader(http.StatusBadRequest)
+		fmt.Fprintln(w, "profile duration exceeds server's WriteTimeout")
+		return
+	}
+
 	// Set Content Type assuming StartCPUProfile will work,
 	// because if it does it starts writing.
 	w.Header().Set("Content-Type", "application/octet-stream")
@@ -105,6 +124,7 @@
 		// Can change header back to text content
 		// and send error code.
 		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+		w.Header().Set("X-Go-Pprof", "1")
 		w.WriteHeader(http.StatusInternalServerError)
 		fmt.Fprintf(w, "Could not enable CPU profiling: %s\n", err)
 		return
@@ -122,20 +142,28 @@
 		sec = 1
 	}
 
+	if durationExceedsWriteTimeout(r, sec) {
+		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+		w.Header().Set("X-Go-Pprof", "1")
+		w.WriteHeader(http.StatusBadRequest)
+		fmt.Fprintln(w, "profile duration exceeds server's WriteTimeout")
+		return
+	}
+
 	// Set Content Type assuming trace.Start will work,
 	// because if it does it starts writing.
 	w.Header().Set("Content-Type", "application/octet-stream")
-	w.Write([]byte("tracing not yet supported with gccgo"))
-	// if err := trace.Start(w); err != nil {
-	// 	// trace.Start failed, so no writes yet.
-	// 	// Can change header back to text content and send error code.
-	// 	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
-	// 	w.WriteHeader(http.StatusInternalServerError)
-	// 	fmt.Fprintf(w, "Could not enable tracing: %s\n", err)
-	// 	return
-	// }
-	// sleep(w, time.Duration(sec*float64(time.Second)))
-	// trace.Stop()
+	if err := trace.Start(w); err != nil {
+		// trace.Start failed, so no writes yet.
+		// Can change header back to text content and send error code.
+		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+		w.Header().Set("X-Go-Pprof", "1")
+		w.WriteHeader(http.StatusInternalServerError)
+		fmt.Fprintf(w, "Could not enable tracing: %s\n", err)
+		return
+	}
+	sleep(w, time.Duration(sec*float64(time.Second)))
+	trace.Stop()
 }
 
 // Symbol looks up the program counters listed in the request,
@@ -207,7 +235,6 @@
 		runtime.GC()
 	}
 	p.WriteTo(w, debug)
-	return
 }
 
 // Index responds with the pprof-formatted profile named by the request.
diff --git a/libgo/go/net/http/proxy_test.go b/libgo/go/net/http/proxy_test.go
index 823d144..f59a551 100644
--- a/libgo/go/net/http/proxy_test.go
+++ b/libgo/go/net/http/proxy_test.go
@@ -75,7 +75,13 @@
 
 func ResetProxyEnv() {
 	for _, v := range []string{"HTTP_PROXY", "http_proxy", "NO_PROXY", "no_proxy"} {
-		os.Setenv(v, "")
+		os.Unsetenv(v)
 	}
 	ResetCachedEnvironment()
 }
+
+func TestInvalidNoProxy(t *testing.T) {
+	ResetProxyEnv()
+	os.Setenv("NO_PROXY", ":1")
+	useProxy("example.com:80") // should not panic
+}
diff --git a/libgo/go/net/http/request.go b/libgo/go/net/http/request.go
index fb6bb0a..13f367c 100644
--- a/libgo/go/net/http/request.go
+++ b/libgo/go/net/http/request.go
@@ -27,8 +27,6 @@
 	"sync"
 
 	"golang_org/x/net/idna"
-	"golang_org/x/text/unicode/norm"
-	"golang_org/x/text/width"
 )
 
 const (
@@ -331,6 +329,16 @@
 	r2 := new(Request)
 	*r2 = *r
 	r2.ctx = ctx
+
+	// Deep copy the URL because it isn't
+	// a map and the URL is mutable by users
+	// of WithContext.
+	if r.URL != nil {
+		r2URL := new(url.URL)
+		*r2URL = *r.URL
+		r2.URL = r2URL
+	}
+
 	return r2
 }
 
@@ -341,18 +349,6 @@
 		r.ProtoMajor == major && r.ProtoMinor >= minor
 }
 
-// protoAtLeastOutgoing is like ProtoAtLeast, but is for outgoing
-// requests (see issue 18407) where these fields aren't supposed to
-// matter.  As a minor fix for Go 1.8, at least treat (0, 0) as
-// matching HTTP/1.1 or HTTP/1.0.  Only HTTP/1.1 is used.
-// TODO(bradfitz): ideally remove this whole method. It shouldn't be used.
-func (r *Request) protoAtLeastOutgoing(major, minor int) bool {
-	if r.ProtoMajor == 0 && r.ProtoMinor == 0 && major == 1 && minor <= 1 {
-		return true
-	}
-	return r.ProtoAtLeast(major, minor)
-}
-
 // UserAgent returns the client's User-Agent, if sent in the request.
 func (r *Request) UserAgent() string {
 	return r.Header.Get("User-Agent")
@@ -621,6 +617,9 @@
 	// Write body and trailer
 	err = tw.WriteBody(w)
 	if err != nil {
+		if tw.bodyReadError == err {
+			err = requestBodyReadError{err}
+		}
 		return err
 	}
 
@@ -630,17 +629,25 @@
 	return nil
 }
 
+// requestBodyReadError wraps an error from (*Request).write to indicate
+// that the error came from a Read call on the Request.Body.
+// This error type should not escape the net/http package to users.
+type requestBodyReadError struct{ error }
+
 func idnaASCII(v string) (string, error) {
+	// TODO: Consider removing this check after verifying performance is okay.
+	// Right now punycode verification, length checks, context checks, and the
+	// permissible character tests are all omitted. It also prevents the ToASCII
+	// call from salvaging an invalid IDN, when possible. As a result it may be
+	// possible to have two IDNs that appear identical to the user where the
+	// ASCII-only version causes an error downstream whereas the non-ASCII
+	// version does not.
+	// Note that for correct ASCII IDNs ToASCII will only do considerably more
+	// work, but it will not cause an allocation.
 	if isASCII(v) {
 		return v, nil
 	}
-	// The idna package doesn't do everything from
-	// https://tools.ietf.org/html/rfc5895 so we do it here.
-	// TODO(bradfitz): should the idna package do this instead?
-	v = strings.ToLower(v)
-	v = width.Fold.String(v)
-	v = norm.NFC.String(v)
-	return idna.ToASCII(v)
+	return idna.Lookup.ToASCII(v)
 }
 
 // cleanHost cleans up the host sent in request's Host header.
@@ -755,7 +762,7 @@
 // exact value (instead of -1), GetBody is populated (so 307 and 308
 // redirects can replay the body), and Body is set to NoBody if the
 // ContentLength is 0.
-func NewRequest(method, urlStr string, body io.Reader) (*Request, error) {
+func NewRequest(method, url string, body io.Reader) (*Request, error) {
 	if method == "" {
 		// We document that "" means "GET" for Request.Method, and people have
 		// relied on that from NewRequest, so keep that working.
@@ -765,7 +772,7 @@
 	if !validMethod(method) {
 		return nil, fmt.Errorf("net/http: invalid method %q", method)
 	}
-	u, err := url.Parse(urlStr)
+	u, err := parseURL(url) // Just url.Parse (url is shadowed for godoc).
 	if err != nil {
 		return nil, err
 	}
@@ -930,6 +937,9 @@
 	if !ok {
 		return nil, &badStringError{"malformed HTTP request", s}
 	}
+	if !validMethod(req.Method) {
+		return nil, &badStringError{"invalid method", req.Method}
+	}
 	rawurl := req.RequestURI
 	if req.ProtoMajor, req.ProtoMinor, ok = ParseHTTPVersion(req.Proto); !ok {
 		return nil, &badStringError{"malformed HTTP version", req.Proto}
@@ -1021,11 +1031,6 @@
 	err error         // sticky error
 }
 
-func (l *maxBytesReader) tooLarge() (n int, err error) {
-	l.err = errors.New("http: request body too large")
-	return 0, l.err
-}
-
 func (l *maxBytesReader) Read(p []byte) (n int, err error) {
 	if l.err != nil {
 		return 0, l.err
@@ -1297,7 +1302,7 @@
 }
 
 func (r *Request) isReplayable() bool {
-	if r.Body == nil {
+	if r.Body == nil || r.Body == NoBody || r.GetBody != nil {
 		switch valueOrDefault(r.Method, "GET") {
 		case "GET", "HEAD", "OPTIONS", "TRACE":
 			return true
diff --git a/libgo/go/net/http/request_test.go b/libgo/go/net/http/request_test.go
index e674837..967156b 100644
--- a/libgo/go/net/http/request_test.go
+++ b/libgo/go/net/http/request_test.go
@@ -7,6 +7,7 @@
 import (
 	"bufio"
 	"bytes"
+	"context"
 	"encoding/base64"
 	"fmt"
 	"io"
@@ -785,6 +786,28 @@
 	}
 }
 
+func TestWithContextDeepCopiesURL(t *testing.T) {
+	req, err := NewRequest("POST", "https://golang.org/", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	reqCopy := req.WithContext(context.Background())
+	reqCopy.URL.Scheme = "http"
+
+	firstURL, secondURL := req.URL.String(), reqCopy.URL.String()
+	if firstURL == secondURL {
+		t.Errorf("unexpected change to original request's URL")
+	}
+
+	// And also check we don't crash on nil (Issue 20601)
+	req.URL = nil
+	reqCopy = req.WithContext(context.Background())
+	if reqCopy.URL != nil {
+		t.Error("expected nil URL in cloned request")
+	}
+}
+
 // verify that NewRequest sets Request.GetBody and that it works
 func TestNewRequestGetBody(t *testing.T) {
 	tests := []struct {
diff --git a/libgo/go/net/http/response.go b/libgo/go/net/http/response.go
index ae118fb..0357b60 100644
--- a/libgo/go/net/http/response.go
+++ b/libgo/go/net/http/response.go
@@ -37,9 +37,10 @@
 	// Header maps header keys to values. If the response had multiple
 	// headers with the same key, they may be concatenated, with comma
 	// delimiters.  (Section 4.2 of RFC 2616 requires that multiple headers
-	// be semantically equivalent to a comma-delimited sequence.) Values
-	// duplicated by other fields in this struct (e.g., ContentLength) are
-	// omitted from Header.
+	// be semantically equivalent to a comma-delimited sequence.) When
+	// Header values are duplicated by other fields in this struct (e.g.,
+	// ContentLength, TransferEncoding, Trailer), the field values are
+	// authoritative.
 	//
 	// Keys in the map are canonicalized (see CanonicalHeaderKey).
 	Header Header
@@ -152,23 +153,23 @@
 		}
 		return nil, err
 	}
-	f := strings.SplitN(line, " ", 3)
-	if len(f) < 2 {
+	if i := strings.IndexByte(line, ' '); i == -1 {
 		return nil, &badStringError{"malformed HTTP response", line}
+	} else {
+		resp.Proto = line[:i]
+		resp.Status = strings.TrimLeft(line[i+1:], " ")
 	}
-	reasonPhrase := ""
-	if len(f) > 2 {
-		reasonPhrase = f[2]
+	statusCode := resp.Status
+	if i := strings.IndexByte(resp.Status, ' '); i != -1 {
+		statusCode = resp.Status[:i]
 	}
-	if len(f[1]) != 3 {
-		return nil, &badStringError{"malformed HTTP status code", f[1]}
+	if len(statusCode) != 3 {
+		return nil, &badStringError{"malformed HTTP status code", statusCode}
 	}
-	resp.StatusCode, err = strconv.Atoi(f[1])
+	resp.StatusCode, err = strconv.Atoi(statusCode)
 	if err != nil || resp.StatusCode < 0 {
-		return nil, &badStringError{"malformed HTTP status code", f[1]}
+		return nil, &badStringError{"malformed HTTP status code", statusCode}
 	}
-	resp.Status = f[1] + " " + reasonPhrase
-	resp.Proto = f[0]
 	var ok bool
 	if resp.ProtoMajor, resp.ProtoMinor, ok = ParseHTTPVersion(resp.Proto); !ok {
 		return nil, &badStringError{"malformed HTTP version", resp.Proto}
@@ -320,3 +321,9 @@
 	// Success
 	return nil
 }
+
+func (r *Response) closeBody() {
+	if r.Body != nil {
+		r.Body.Close()
+	}
+}
diff --git a/libgo/go/net/http/response_test.go b/libgo/go/net/http/response_test.go
index 660d517..f1a50bd 100644
--- a/libgo/go/net/http/response_test.go
+++ b/libgo/go/net/http/response_test.go
@@ -318,7 +318,7 @@
 	{
 		"HTTP/1.0 303\r\n\r\n",
 		Response{
-			Status:        "303 ",
+			Status:        "303",
 			StatusCode:    303,
 			Proto:         "HTTP/1.0",
 			ProtoMajor:    1,
@@ -532,6 +532,29 @@
 		},
 		"\x1f\x8b\b\x00\x00\x00\x00\x00\x00\x00s\xf3\xf7\a\x00\xab'\xd4\x1a\x03\x00\x00\x00",
 	},
+
+	// Issue 19989: two spaces between HTTP version and status.
+	{
+		"HTTP/1.0  401 Unauthorized\r\n" +
+			"Content-type: text/html\r\n" +
+			"WWW-Authenticate: Basic realm=\"\"\r\n\r\n" +
+			"Your Authentication failed.\r\n",
+		Response{
+			Status:     "401 Unauthorized",
+			StatusCode: 401,
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			ProtoMinor: 0,
+			Request:    dummyReq("GET"),
+			Header: Header{
+				"Content-Type":     {"text/html"},
+				"Www-Authenticate": {`Basic realm=""`},
+			},
+			Close:         true,
+			ContentLength: -1,
+		},
+		"Your Authentication failed.\r\n",
+	},
 }
 
 // tests successful calls to ReadResponse, and inspects the returned Response.
@@ -926,3 +949,29 @@
 		t.Errorf("needsSniff empty Content-Type = %t; want %t", got, want)
 	}
 }
+
+// A response should only write out single Connection: close header. Tests #19499.
+func TestResponseWritesOnlySingleConnectionClose(t *testing.T) {
+	const connectionCloseHeader = "Connection: close"
+
+	res, err := ReadResponse(bufio.NewReader(strings.NewReader("HTTP/1.0 200 OK\r\n\r\nAAAA")), nil)
+	if err != nil {
+		t.Fatalf("ReadResponse failed %v", err)
+	}
+
+	var buf1 bytes.Buffer
+	if err = res.Write(&buf1); err != nil {
+		t.Fatalf("Write failed %v", err)
+	}
+	if res, err = ReadResponse(bufio.NewReader(&buf1), nil); err != nil {
+		t.Fatalf("ReadResponse failed %v", err)
+	}
+
+	var buf2 bytes.Buffer
+	if err = res.Write(&buf2); err != nil {
+		t.Fatalf("Write failed %v", err)
+	}
+	if count := strings.Count(buf2.String(), connectionCloseHeader); count != 1 {
+		t.Errorf("Found %d %q header", count, connectionCloseHeader)
+	}
+}
diff --git a/libgo/go/net/http/serve_test.go b/libgo/go/net/http/serve_test.go
index 73dd56e..7137599 100644
--- a/libgo/go/net/http/serve_test.go
+++ b/libgo/go/net/http/serve_test.go
@@ -337,6 +337,7 @@
 	{"GET", "codesearch.google.com", "/search/", 203, "codesearch.google.com/"},
 	{"GET", "codesearch.google.com", "/search/foo", 203, "codesearch.google.com/"},
 	{"GET", "codesearch.google.com", "/", 203, "codesearch.google.com/"},
+	{"GET", "codesearch.google.com:443", "/", 203, "codesearch.google.com/"},
 	{"GET", "images.google.com", "/search", 201, "/search"},
 	{"GET", "images.google.com", "/search/", 404, ""},
 	{"GET", "images.google.com", "/search/foo", 404, ""},
@@ -460,31 +461,86 @@
 	}
 }
 
+func BenchmarkServeMux(b *testing.B) {
+
+	type test struct {
+		path string
+		code int
+		req  *Request
+	}
+
+	// Build example handlers and requests
+	var tests []test
+	endpoints := []string{"search", "dir", "file", "change", "count", "s"}
+	for _, e := range endpoints {
+		for i := 200; i < 230; i++ {
+			p := fmt.Sprintf("/%s/%d/", e, i)
+			tests = append(tests, test{
+				path: p,
+				code: i,
+				req:  &Request{Method: "GET", Host: "localhost", URL: &url.URL{Path: p}},
+			})
+		}
+	}
+	mux := NewServeMux()
+	for _, tt := range tests {
+		mux.Handle(tt.path, serve(tt.code))
+	}
+
+	rw := httptest.NewRecorder()
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		for _, tt := range tests {
+			*rw = httptest.ResponseRecorder{}
+			h, pattern := mux.Handler(tt.req)
+			h.ServeHTTP(rw, tt.req)
+			if pattern != tt.path || rw.Code != tt.code {
+				b.Fatalf("got %d, %q, want %d, %q", rw.Code, pattern, tt.code, tt.path)
+			}
+		}
+	}
+}
+
 func TestServerTimeouts(t *testing.T) {
 	setParallel(t)
 	defer afterTest(t)
+	// Try three times, with increasing timeouts.
+	tries := []time.Duration{250 * time.Millisecond, 500 * time.Millisecond, 1 * time.Second}
+	for i, timeout := range tries {
+		err := testServerTimeouts(timeout)
+		if err == nil {
+			return
+		}
+		t.Logf("failed at %v: %v", timeout, err)
+		if i != len(tries)-1 {
+			t.Logf("retrying at %v ...", tries[i+1])
+		}
+	}
+	t.Fatal("all attempts failed")
+}
+
+func testServerTimeouts(timeout time.Duration) error {
 	reqNum := 0
 	ts := httptest.NewUnstartedServer(HandlerFunc(func(res ResponseWriter, req *Request) {
 		reqNum++
 		fmt.Fprintf(res, "req=%d", reqNum)
 	}))
-	ts.Config.ReadTimeout = 250 * time.Millisecond
-	ts.Config.WriteTimeout = 250 * time.Millisecond
+	ts.Config.ReadTimeout = timeout
+	ts.Config.WriteTimeout = timeout
 	ts.Start()
 	defer ts.Close()
 
 	// Hit the HTTP server successfully.
-	tr := &Transport{DisableKeepAlives: true} // they interfere with this test
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	r, err := c.Get(ts.URL)
 	if err != nil {
-		t.Fatalf("http Get #1: %v", err)
+		return fmt.Errorf("http Get #1: %v", err)
 	}
 	got, err := ioutil.ReadAll(r.Body)
 	expected := "req=1"
 	if string(got) != expected || err != nil {
-		t.Errorf("Unexpected response for request #1; got %q ,%v; expected %q, nil",
+		return fmt.Errorf("Unexpected response for request #1; got %q ,%v; expected %q, nil",
 			string(got), err, expected)
 	}
 
@@ -492,17 +548,18 @@
 	t1 := time.Now()
 	conn, err := net.Dial("tcp", ts.Listener.Addr().String())
 	if err != nil {
-		t.Fatalf("Dial: %v", err)
+		return fmt.Errorf("Dial: %v", err)
 	}
 	buf := make([]byte, 1)
 	n, err := conn.Read(buf)
 	conn.Close()
 	latency := time.Since(t1)
 	if n != 0 || err != io.EOF {
-		t.Errorf("Read = %v, %v, wanted %v, %v", n, err, 0, io.EOF)
+		return fmt.Errorf("Read = %v, %v, wanted %v, %v", n, err, 0, io.EOF)
 	}
-	if latency < 200*time.Millisecond /* fudge from 250 ms above */ {
-		t.Errorf("got EOF after %s, want >= %s", latency, 200*time.Millisecond)
+	minLatency := timeout / 5 * 4
+	if latency < minLatency {
+		return fmt.Errorf("got EOF after %s, want >= %s", latency, minLatency)
 	}
 
 	// Hit the HTTP server successfully again, verifying that the
@@ -510,29 +567,31 @@
 	// get "req=2", not "req=3")
 	r, err = c.Get(ts.URL)
 	if err != nil {
-		t.Fatalf("http Get #2: %v", err)
+		return fmt.Errorf("http Get #2: %v", err)
 	}
 	got, err = ioutil.ReadAll(r.Body)
+	r.Body.Close()
 	expected = "req=2"
 	if string(got) != expected || err != nil {
-		t.Errorf("Get #2 got %q, %v, want %q, nil", string(got), err, expected)
+		return fmt.Errorf("Get #2 got %q, %v, want %q, nil", string(got), err, expected)
 	}
 
 	if !testing.Short() {
 		conn, err := net.Dial("tcp", ts.Listener.Addr().String())
 		if err != nil {
-			t.Fatalf("Dial: %v", err)
+			return fmt.Errorf("long Dial: %v", err)
 		}
 		defer conn.Close()
 		go io.Copy(ioutil.Discard, conn)
 		for i := 0; i < 5; i++ {
 			_, err := conn.Write([]byte("GET / HTTP/1.1\r\nHost: foo\r\n\r\n"))
 			if err != nil {
-				t.Fatalf("on write %d: %v", i, err)
+				return fmt.Errorf("on write %d: %v", i, err)
 			}
-			time.Sleep(ts.Config.ReadTimeout / 2)
+			time.Sleep(timeout / 2)
 		}
 	}
+	return nil
 }
 
 // Test that the HTTP/2 server handles Server.WriteTimeout (Issue 18437)
@@ -548,12 +607,10 @@
 	ts.StartTLS()
 	defer ts.Close()
 
-	tr := newTLSTransport(t, ts)
-	defer tr.CloseIdleConnections()
-	if err := ExportHttp2ConfigureTransport(tr); err != nil {
+	c := ts.Client()
+	if err := ExportHttp2ConfigureTransport(c.Transport.(*Transport)); err != nil {
 		t.Fatal(err)
 	}
-	c := &Client{Transport: tr}
 
 	for i := 1; i <= 3; i++ {
 		req, err := NewRequest("GET", ts.URL, nil)
@@ -585,13 +642,139 @@
 	}
 }
 
+// tryTimeouts runs testFunc with increasing timeouts. Test passes on first success,
+// and fails if all timeouts fail.
+func tryTimeouts(t *testing.T, testFunc func(timeout time.Duration) error) {
+	tries := []time.Duration{250 * time.Millisecond, 500 * time.Millisecond, 1 * time.Second}
+	for i, timeout := range tries {
+		err := testFunc(timeout)
+		if err == nil {
+			return
+		}
+		t.Logf("failed at %v: %v", timeout, err)
+		if i != len(tries)-1 {
+			t.Logf("retrying at %v ...", tries[i+1])
+		}
+	}
+	t.Fatal("all attempts failed")
+}
+
+// Test that the HTTP/2 server RSTs stream on slow write.
+func TestHTTP2WriteDeadlineEnforcedPerStream(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping in short mode")
+	}
+	setParallel(t)
+	defer afterTest(t)
+	tryTimeouts(t, testHTTP2WriteDeadlineEnforcedPerStream)
+}
+
+func testHTTP2WriteDeadlineEnforcedPerStream(timeout time.Duration) error {
+	reqNum := 0
+	ts := httptest.NewUnstartedServer(HandlerFunc(func(res ResponseWriter, req *Request) {
+		reqNum++
+		if reqNum == 1 {
+			return // first request succeeds
+		}
+		time.Sleep(timeout) // second request times out
+	}))
+	ts.Config.WriteTimeout = timeout / 2
+	ts.TLS = &tls.Config{NextProtos: []string{"h2"}}
+	ts.StartTLS()
+	defer ts.Close()
+
+	c := ts.Client()
+	if err := ExportHttp2ConfigureTransport(c.Transport.(*Transport)); err != nil {
+		return fmt.Errorf("ExportHttp2ConfigureTransport: %v", err)
+	}
+
+	req, err := NewRequest("GET", ts.URL, nil)
+	if err != nil {
+		return fmt.Errorf("NewRequest: %v", err)
+	}
+	r, err := c.Do(req)
+	if err != nil {
+		return fmt.Errorf("http2 Get #1: %v", err)
+	}
+	r.Body.Close()
+	if r.ProtoMajor != 2 {
+		return fmt.Errorf("http2 Get expected HTTP/2.0, got %q", r.Proto)
+	}
+
+	req, err = NewRequest("GET", ts.URL, nil)
+	if err != nil {
+		return fmt.Errorf("NewRequest: %v", err)
+	}
+	r, err = c.Do(req)
+	if err == nil {
+		r.Body.Close()
+		if r.ProtoMajor != 2 {
+			return fmt.Errorf("http2 Get expected HTTP/2.0, got %q", r.Proto)
+		}
+		return fmt.Errorf("http2 Get #2 expected error, got nil")
+	}
+	expected := "stream ID 3; INTERNAL_ERROR" // client IDs are odd, second stream should be 3
+	if !strings.Contains(err.Error(), expected) {
+		return fmt.Errorf("http2 Get #2: expected error to contain %q, got %q", expected, err)
+	}
+	return nil
+}
+
+// Test that the HTTP/2 server does not send RST when WriteDeadline not set.
+func TestHTTP2NoWriteDeadline(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping in short mode")
+	}
+	setParallel(t)
+	defer afterTest(t)
+	tryTimeouts(t, testHTTP2NoWriteDeadline)
+}
+
+func testHTTP2NoWriteDeadline(timeout time.Duration) error {
+	reqNum := 0
+	ts := httptest.NewUnstartedServer(HandlerFunc(func(res ResponseWriter, req *Request) {
+		reqNum++
+		if reqNum == 1 {
+			return // first request succeeds
+		}
+		time.Sleep(timeout) // second request timesout
+	}))
+	ts.TLS = &tls.Config{NextProtos: []string{"h2"}}
+	ts.StartTLS()
+	defer ts.Close()
+
+	c := ts.Client()
+	if err := ExportHttp2ConfigureTransport(c.Transport.(*Transport)); err != nil {
+		return fmt.Errorf("ExportHttp2ConfigureTransport: %v", err)
+	}
+
+	for i := 0; i < 2; i++ {
+		req, err := NewRequest("GET", ts.URL, nil)
+		if err != nil {
+			return fmt.Errorf("NewRequest: %v", err)
+		}
+		r, err := c.Do(req)
+		if err != nil {
+			return fmt.Errorf("http2 Get #%d: %v", i, err)
+		}
+		r.Body.Close()
+		if r.ProtoMajor != 2 {
+			return fmt.Errorf("http2 Get expected HTTP/2.0, got %q", r.Proto)
+		}
+	}
+	return nil
+}
+
 // golang.org/issue/4741 -- setting only a write timeout that triggers
 // shouldn't cause a handler to block forever on reads (next HTTP
 // request) that will never happen.
 func TestOnlyWriteTimeout(t *testing.T) {
 	setParallel(t)
 	defer afterTest(t)
-	var conn net.Conn
+	var (
+		mu   sync.RWMutex
+		conn net.Conn
+	)
 	var afterTimeoutErrc = make(chan error, 1)
 	ts := httptest.NewUnstartedServer(HandlerFunc(func(w ResponseWriter, req *Request) {
 		buf := make([]byte, 512<<10)
@@ -600,17 +783,21 @@
 			t.Errorf("handler Write error: %v", err)
 			return
 		}
+		mu.RLock()
+		defer mu.RUnlock()
+		if conn == nil {
+			t.Error("no established connection found")
+			return
+		}
 		conn.SetWriteDeadline(time.Now().Add(-30 * time.Second))
 		_, err = w.Write(buf)
 		afterTimeoutErrc <- err
 	}))
-	ts.Listener = trackLastConnListener{ts.Listener, &conn}
+	ts.Listener = trackLastConnListener{ts.Listener, &mu, &conn}
 	ts.Start()
 	defer ts.Close()
 
-	tr := &Transport{DisableKeepAlives: false}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 
 	errc := make(chan error)
 	go func() {
@@ -620,6 +807,7 @@
 			return
 		}
 		_, err = io.Copy(ioutil.Discard, res.Body)
+		res.Body.Close()
 		errc <- err
 	}()
 	select {
@@ -638,12 +826,18 @@
 // trackLastConnListener tracks the last net.Conn that was accepted.
 type trackLastConnListener struct {
 	net.Listener
+
+	mu   *sync.RWMutex
 	last *net.Conn // destination
 }
 
 func (l trackLastConnListener) Accept() (c net.Conn, err error) {
 	c, err = l.Listener.Accept()
-	*l.last = c
+	if err == nil {
+		l.mu.Lock()
+		*l.last = c
+		l.mu.Unlock()
+	}
 	return
 }
 
@@ -671,8 +865,7 @@
 	ts := httptest.NewServer(handler)
 	defer ts.Close()
 
-	c := &Client{Transport: new(Transport)}
-	defer closeClient(c)
+	c := ts.Client()
 
 	// Note: this relies on the assumption (which is true) that
 	// Get sends HTTP/1.1 or greater requests. Otherwise the
@@ -936,7 +1129,6 @@
 
 // Issue 12943
 func TestServerAllowsBlockingRemoteAddr(t *testing.T) {
-	setParallel(t)
 	defer afterTest(t)
 	ts := httptest.NewUnstartedServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 		fmt.Fprintf(w, "RA:%s", r.RemoteAddr)
@@ -949,21 +1141,22 @@
 	ts.Start()
 	defer ts.Close()
 
-	tr := &Transport{DisableKeepAlives: true}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr, Timeout: time.Second}
+	c := ts.Client()
+	c.Timeout = time.Second
+	// Force separate connection for each:
+	c.Transport.(*Transport).DisableKeepAlives = true
 
-	fetch := func(response chan string) {
+	fetch := func(num int, response chan<- string) {
 		resp, err := c.Get(ts.URL)
 		if err != nil {
-			t.Error(err)
+			t.Errorf("Request %d: %v", num, err)
 			response <- ""
 			return
 		}
 		defer resp.Body.Close()
 		body, err := ioutil.ReadAll(resp.Body)
 		if err != nil {
-			t.Error(err)
+			t.Errorf("Request %d: %v", num, err)
 			response <- ""
 			return
 		}
@@ -972,14 +1165,14 @@
 
 	// Start a request. The server will block on getting conn.RemoteAddr.
 	response1c := make(chan string, 1)
-	go fetch(response1c)
+	go fetch(1, response1c)
 
 	// Wait for the server to accept it; grab the connection.
 	conn1 := <-conns
 
 	// Start another request and grab its connection
 	response2c := make(chan string, 1)
-	go fetch(response2c)
+	go fetch(2, response2c)
 	var conn2 net.Conn
 
 	select {
@@ -1022,9 +1215,7 @@
 	}))
 	defer ts.Close()
 
-	c := &Client{Transport: new(Transport)}
-	defer closeClient(c)
-
+	c := ts.Client()
 	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatalf("Get error: %v", err)
@@ -1145,12 +1336,7 @@
 			t.Errorf("expected test TLS server to start with https://, got %q", ts.URL)
 			return
 		}
-		noVerifyTransport := &Transport{
-			TLSClientConfig: &tls.Config{
-				InsecureSkipVerify: true,
-			},
-		}
-		client := &Client{Transport: noVerifyTransport}
+		client := ts.Client()
 		res, err := client.Get(ts.URL)
 		if err != nil {
 			t.Error(err)
@@ -1171,6 +1357,59 @@
 	})
 }
 
+func TestServeTLS(t *testing.T) {
+	// Not parallel: uses global test hooks.
+	defer afterTest(t)
+	defer SetTestHookServerServe(nil)
+
+	cert, err := tls.X509KeyPair(internal.LocalhostCert, internal.LocalhostKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	tlsConf := &tls.Config{
+		Certificates: []tls.Certificate{cert},
+	}
+
+	ln := newLocalListener(t)
+	defer ln.Close()
+	addr := ln.Addr().String()
+
+	serving := make(chan bool, 1)
+	SetTestHookServerServe(func(s *Server, ln net.Listener) {
+		serving <- true
+	})
+	handler := HandlerFunc(func(w ResponseWriter, r *Request) {})
+	s := &Server{
+		Addr:      addr,
+		TLSConfig: tlsConf,
+		Handler:   handler,
+	}
+	errc := make(chan error, 1)
+	go func() { errc <- s.ServeTLS(ln, "", "") }()
+	select {
+	case err := <-errc:
+		t.Fatalf("ServeTLS: %v", err)
+	case <-serving:
+	case <-time.After(5 * time.Second):
+		t.Fatal("timeout")
+	}
+
+	c, err := tls.Dial("tcp", ln.Addr().String(), &tls.Config{
+		InsecureSkipVerify: true,
+		NextProtos:         []string{"h2", "http/1.1"},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Close()
+	if got, want := c.ConnectionState().NegotiatedProtocol, "h2"; got != want {
+		t.Errorf("NegotiatedProtocol = %q; want %q", got, want)
+	}
+	if got, want := c.ConnectionState().NegotiatedProtocolIsMutual, true; got != want {
+		t.Errorf("NegotiatedProtocolIsMutual = %v; want %v", got, want)
+	}
+}
+
 // Issue 15908
 func TestAutomaticHTTP2_Serve_NoTLSConfig(t *testing.T) {
 	testAutomaticHTTP2_Serve(t, nil, true)
@@ -1967,8 +2206,7 @@
 	ts := httptest.NewServer(TimeoutHandler(delayHi, 20*time.Millisecond, ""))
 	defer ts.Close()
 
-	c := &Client{Transport: new(Transport)}
-	defer closeClient(c)
+	c := ts.Client()
 
 	var wg sync.WaitGroup
 	gate := make(chan bool, 10)
@@ -2011,8 +2249,8 @@
 	if testing.Short() {
 		n = 10
 	}
-	c := &Client{Transport: new(Transport)}
-	defer closeClient(c)
+
+	c := ts.Client()
 	for i := 0; i < n; i++ {
 		gate <- true
 		wg.Add(1)
@@ -2099,8 +2337,7 @@
 	ts := httptest.NewServer(TimeoutHandler(handler, timeout, ""))
 	defer ts.Close()
 
-	c := &Client{Transport: new(Transport)}
-	defer closeClient(c)
+	c := ts.Client()
 
 	// Issue was caused by the timeout handler starting the timer when
 	// was created, not when the request. So wait for more than the timeout
@@ -2127,8 +2364,7 @@
 	ts := httptest.NewServer(TimeoutHandler(handler, timeout, ""))
 	defer ts.Close()
 
-	c := &Client{Transport: new(Transport)}
-	defer closeClient(c)
+	c := ts.Client()
 
 	res, err := c.Get(ts.URL)
 	if err != nil {
@@ -2364,9 +2600,7 @@
 	ts.Start()
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatal(err)
@@ -2411,8 +2645,7 @@
 	ts := httptest.NewServer(StripPrefix("/foo", h))
 	defer ts.Close()
 
-	c := &Client{Transport: new(Transport)}
-	defer closeClient(c)
+	c := ts.Client()
 
 	res, err := c.Get(ts.URL + "/foo/bar")
 	if err != nil {
@@ -2433,6 +2666,16 @@
 	res.Body.Close()
 }
 
+// https://golang.org/issue/18952.
+func TestStripPrefix_notModifyRequest(t *testing.T) {
+	h := StripPrefix("/foo", NotFoundHandler())
+	req := httptest.NewRequest("GET", "/foo/bar", nil)
+	h.ServeHTTP(httptest.NewRecorder(), req)
+	if req.URL.Path != "/foo/bar" {
+		t.Errorf("StripPrefix should not modify the provided Request, but it did")
+	}
+}
+
 func TestRequestLimit_h1(t *testing.T) { testRequestLimit(t, h1Mode) }
 func TestRequestLimit_h2(t *testing.T) { testRequestLimit(t, h2Mode) }
 func testRequestLimit(t *testing.T, h2 bool) {
@@ -3512,8 +3755,8 @@
 
 // Test that a hanging Request.Body.Read from another goroutine can't
 // cause the Handler goroutine's Request.Body.Close to block.
+// See issue 7121.
 func TestRequestBodyCloseDoesntBlock(t *testing.T) {
-	t.Skipf("Skipping known issue; see golang.org/issue/7121")
 	if testing.Short() {
 		t.Skip("skipping in -short mode")
 	}
@@ -3644,9 +3887,7 @@
 	}
 	ts.Start()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 
 	mustGet := func(url string, headers ...string) {
 		req, err := NewRequest("GET", url, nil)
@@ -4170,6 +4411,9 @@
 		// Make an exception for HTTP upgrade requests:
 		{"PRI * HTTP/2.0", "", 200},
 
+		// Also an exception for CONNECT requests: (Issue 18215)
+		{"CONNECT golang.org:443 HTTP/1.1", "", 200},
+
 		// But not other HTTP/2 stuff:
 		{"PRI / HTTP/2.0", "", 400},
 		{"GET / HTTP/2.0", "", 400},
@@ -4373,13 +4617,6 @@
 		if _, ok := got.(*Server); !ok {
 			t.Errorf("context value = %T; want *http.Server", got)
 		}
-
-		got = ctx.Value(LocalAddrContextKey)
-		if addr, ok := got.(net.Addr); !ok {
-			t.Errorf("local addr value = %T; want net.Addr", got)
-		} else if fmt.Sprint(addr) != r.Host {
-			t.Errorf("local addr = %v; want %v", addr, r.Host)
-		}
 	}))
 	defer cst.close()
 	res, err := cst.c.Get(cst.ts.URL)
@@ -4389,6 +4626,37 @@
 	res.Body.Close()
 }
 
+func TestServerContext_LocalAddrContextKey_h1(t *testing.T) {
+	testServerContext_LocalAddrContextKey(t, h1Mode)
+}
+func TestServerContext_LocalAddrContextKey_h2(t *testing.T) {
+	testServerContext_LocalAddrContextKey(t, h2Mode)
+}
+func testServerContext_LocalAddrContextKey(t *testing.T, h2 bool) {
+	setParallel(t)
+	defer afterTest(t)
+	ch := make(chan interface{}, 1)
+	cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
+		ch <- r.Context().Value(LocalAddrContextKey)
+	}))
+	defer cst.close()
+	if _, err := cst.c.Head(cst.ts.URL); err != nil {
+		t.Fatal(err)
+	}
+
+	host := cst.ts.Listener.Addr().String()
+	select {
+	case got := <-ch:
+		if addr, ok := got.(net.Addr); !ok {
+			t.Errorf("local addr value = %T; want net.Addr", got)
+		} else if fmt.Sprint(addr) != host {
+			t.Errorf("local addr = %v; want %v", addr, host)
+		}
+	case <-time.After(5 * time.Second):
+		t.Error("timed out")
+	}
+}
+
 // https://golang.org/issue/15960
 func TestHandlerSetTransferEncodingChunked(t *testing.T) {
 	setParallel(t)
@@ -4481,15 +4749,9 @@
 	b.ResetTimer()
 	b.SetParallelism(parallelism)
 	b.RunParallel(func(pb *testing.PB) {
-		noVerifyTransport := &Transport{
-			TLSClientConfig: &tls.Config{
-				InsecureSkipVerify: true,
-			},
-		}
-		defer noVerifyTransport.CloseIdleConnections()
-		client := &Client{Transport: noVerifyTransport}
+		c := ts.Client()
 		for pb.Next() {
-			res, err := client.Get(ts.URL)
+			res, err := c.Get(ts.URL)
 			if err != nil {
 				b.Logf("Get: %v", err)
 				continue
@@ -4924,10 +5186,7 @@
 	ts.Config.IdleTimeout = 2 * time.Second
 	ts.Start()
 	defer ts.Close()
-
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 
 	get := func() string {
 		res, err := c.Get(ts.URL)
@@ -4988,9 +5247,8 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	get := func() string { return get(t, c, ts.URL) }
 
@@ -5030,7 +5288,8 @@
 	defer afterTest(t)
 	var doShutdown func() // set later
 	var shutdownRes = make(chan error, 1)
-	cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
+	var gotOnShutdown = make(chan struct{}, 1)
+	handler := HandlerFunc(func(w ResponseWriter, r *Request) {
 		go doShutdown()
 		// Shutdown is graceful, so it should not interrupt
 		// this in-flight response. Add a tiny sleep here to
@@ -5038,7 +5297,10 @@
 		// bugs.
 		time.Sleep(20 * time.Millisecond)
 		io.WriteString(w, r.RemoteAddr)
-	}))
+	})
+	cst := newClientServerTest(t, h2, handler, func(srv *httptest.Server) {
+		srv.Config.RegisterOnShutdown(func() { gotOnShutdown <- struct{}{} })
+	})
 	defer cst.close()
 
 	doShutdown = func() {
@@ -5049,6 +5311,11 @@
 	if err := <-shutdownRes; err != nil {
 		t.Fatalf("Shutdown: %v", err)
 	}
+	select {
+	case <-gotOnShutdown:
+	case <-time.After(5 * time.Second):
+		t.Errorf("onShutdown callback not called, RegisterOnShutdown broken?")
+	}
 
 	res, err := cst.c.Get(cst.ts.URL)
 	if err == nil {
@@ -5109,9 +5376,7 @@
 	ts.Start()
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 
 	res, err := c.Get(ts.URL)
 	if err != nil {
@@ -5312,3 +5577,41 @@
 		t.Error("timeout")
 	}
 }
+
+// Issue 18319: test that the Server validates the request method.
+func TestServerValidatesMethod(t *testing.T) {
+	tests := []struct {
+		method string
+		want   int
+	}{
+		{"GET", 200},
+		{"GE(T", 400},
+	}
+	for _, tt := range tests {
+		conn := &testConn{closec: make(chan bool, 1)}
+		io.WriteString(&conn.readBuf, tt.method+" / HTTP/1.1\r\nHost: foo.example\r\n\r\n")
+
+		ln := &oneConnListener{conn}
+		go Serve(ln, serve(200))
+		<-conn.closec
+		res, err := ReadResponse(bufio.NewReader(&conn.writeBuf), nil)
+		if err != nil {
+			t.Errorf("For %s, ReadResponse: %v", tt.method, res)
+			continue
+		}
+		if res.StatusCode != tt.want {
+			t.Errorf("For %s, Status = %d; want %d", tt.method, res.StatusCode, tt.want)
+		}
+	}
+}
+
+func BenchmarkResponseStatusLine(b *testing.B) {
+	b.ReportAllocs()
+	b.RunParallel(func(pb *testing.PB) {
+		bw := bufio.NewWriter(ioutil.Discard)
+		var buf3 [3]byte
+		for pb.Next() {
+			Export_writeStatusLine(bw, true, 200, buf3[:])
+		}
+	})
+}
diff --git a/libgo/go/net/http/server.go b/libgo/go/net/http/server.go
index df70a15..2fa8ab2 100644
--- a/libgo/go/net/http/server.go
+++ b/libgo/go/net/http/server.go
@@ -75,9 +75,10 @@
 // If ServeHTTP panics, the server (the caller of ServeHTTP) assumes
 // that the effect of the panic was isolated to the active request.
 // It recovers the panic, logs a stack trace to the server error log,
-// and hangs up the connection. To abort a handler so the client sees
-// an interrupted response but the server doesn't log an error, panic
-// with the value ErrAbortHandler.
+// and either closes the network connection or sends an HTTP/2
+// RST_STREAM, depending on the HTTP protocol. To abort a handler so
+// the client sees an interrupted response but the server doesn't log
+// an error, panic with the value ErrAbortHandler.
 type Handler interface {
 	ServeHTTP(ResponseWriter, *Request)
 }
@@ -177,6 +178,9 @@
 	//
 	// The returned bufio.Reader may contain unprocessed buffered
 	// data from the client.
+	//
+	// After a call to Hijack, the original Request.Body should
+	// not be used.
 	Hijack() (net.Conn, *bufio.ReadWriter, error)
 }
 
@@ -439,9 +443,10 @@
 
 	handlerDone atomicBool // set true when the handler exits
 
-	// Buffers for Date and Content-Length
-	dateBuf [len(TimeFormat)]byte
-	clenBuf [10]byte
+	// Buffers for Date, Content-Length, and status code
+	dateBuf   [len(TimeFormat)]byte
+	clenBuf   [10]byte
+	statusBuf [3]byte
 
 	// closeNotifyCh is the channel returned by CloseNotify.
 	// TODO(bradfitz): this is currently (for Go 1.8) always
@@ -622,7 +627,6 @@
 	mu      sync.Mutex // guards following
 	hasByte bool
 	byteBuf [1]byte
-	bgErr   error // non-nil means error happened on background read
 	cond    *sync.Cond
 	inRead  bool
 	aborted bool  // set true before conn.rwc deadline is set to past
@@ -731,11 +735,6 @@
 		cr.unlock()
 		return 0, io.EOF
 	}
-	if cr.bgErr != nil {
-		err = cr.bgErr
-		cr.unlock()
-		return 0, err
-	}
 	if len(p) == 0 {
 		cr.unlock()
 		return 0, nil
@@ -839,7 +838,7 @@
 	return int64(srv.maxHeaderBytes()) + 4096 // bufio slop
 }
 
-// wrapper around io.ReaderCloser which on first read, sends an
+// wrapper around io.ReadCloser which on first read, sends an
 // HTTP/1.1 100 Continue header
 type expectContinueReader struct {
 	resp       *response
@@ -948,7 +947,7 @@
 
 	hosts, haveHost := req.Header["Host"]
 	isH2Upgrade := req.isH2Upgrade()
-	if req.ProtoAtLeast(1, 1) && (!haveHost || len(hosts) == 0) && !isH2Upgrade {
+	if req.ProtoAtLeast(1, 1) && (!haveHost || len(hosts) == 0) && !isH2Upgrade && req.Method != "CONNECT" {
 		return nil, badRequestError("missing required Host header")
 	}
 	if len(hosts) > 1 {
@@ -1379,7 +1378,7 @@
 		}
 	}
 
-	w.conn.bufw.WriteString(statusLine(w.req, code))
+	writeStatusLine(w.conn.bufw, w.req.ProtoAtLeast(1, 1), code, w.statusBuf[:])
 	cw.header.WriteSubset(w.conn.bufw, excludeHeader)
 	setHeader.Write(w.conn.bufw)
 	w.conn.bufw.Write(crlf)
@@ -1403,49 +1402,25 @@
 	}
 }
 
-// statusLines is a cache of Status-Line strings, keyed by code (for
-// HTTP/1.1) or negative code (for HTTP/1.0). This is faster than a
-// map keyed by struct of two fields. This map's max size is bounded
-// by 2*len(statusText), two protocol types for each known official
-// status code in the statusText map.
-var (
-	statusMu    sync.RWMutex
-	statusLines = make(map[int]string)
-)
-
-// statusLine returns a response Status-Line (RFC 2616 Section 6.1)
-// for the given request and response status code.
-func statusLine(req *Request, code int) string {
-	// Fast path:
-	key := code
-	proto11 := req.ProtoAtLeast(1, 1)
-	if !proto11 {
-		key = -key
+// writeStatusLine writes an HTTP/1.x Status-Line (RFC 2616 Section 6.1)
+// to bw. is11 is whether the HTTP request is HTTP/1.1. false means HTTP/1.0.
+// code is the response status code.
+// scratch is an optional scratch buffer. If it has at least capacity 3, it's used.
+func writeStatusLine(bw *bufio.Writer, is11 bool, code int, scratch []byte) {
+	if is11 {
+		bw.WriteString("HTTP/1.1 ")
+	} else {
+		bw.WriteString("HTTP/1.0 ")
 	}
-	statusMu.RLock()
-	line, ok := statusLines[key]
-	statusMu.RUnlock()
-	if ok {
-		return line
+	if text, ok := statusText[code]; ok {
+		bw.Write(strconv.AppendInt(scratch[:0], int64(code), 10))
+		bw.WriteByte(' ')
+		bw.WriteString(text)
+		bw.WriteString("\r\n")
+	} else {
+		// don't worry about performance
+		fmt.Fprintf(bw, "%03d status code %d\r\n", code, code)
 	}
-
-	// Slow path:
-	proto := "HTTP/1.0"
-	if proto11 {
-		proto = "HTTP/1.1"
-	}
-	codestring := fmt.Sprintf("%03d", code)
-	text, ok := statusText[code]
-	if !ok {
-		text = "status code " + codestring
-	}
-	line = proto + " " + codestring + " " + text + "\r\n"
-	if ok {
-		statusMu.Lock()
-		defer statusMu.Unlock()
-		statusLines[key] = line
-	}
-	return line
 }
 
 // bodyAllowed reports whether a Write is allowed for this response type.
@@ -1714,6 +1689,7 @@
 // Serve a new connection.
 func (c *conn) serve(ctx context.Context) {
 	c.remoteAddr = c.rwc.RemoteAddr().String()
+	ctx = context.WithValue(ctx, LocalAddrContextKey, c.rwc.LocalAddr())
 	defer func() {
 		if err := recover(); err != nil && err != ErrAbortHandler {
 			const size = 64 << 10
@@ -1973,8 +1949,12 @@
 	}
 	return HandlerFunc(func(w ResponseWriter, r *Request) {
 		if p := strings.TrimPrefix(r.URL.Path, prefix); len(p) < len(r.URL.Path) {
-			r.URL.Path = p
-			h.ServeHTTP(w, r)
+			r2 := new(Request)
+			*r2 = *r
+			r2.URL = new(url.URL)
+			*r2.URL = *r.URL
+			r2.URL.Path = p
+			h.ServeHTTP(w, r2)
 		} else {
 			NotFound(w, r)
 		}
@@ -1986,8 +1966,9 @@
 //
 // The provided code should be in the 3xx range and is usually
 // StatusMovedPermanently, StatusFound or StatusSeeOther.
-func Redirect(w ResponseWriter, r *Request, urlStr string, code int) {
-	if u, err := url.Parse(urlStr); err == nil {
+func Redirect(w ResponseWriter, r *Request, url string, code int) {
+	// parseURL is just url.Parse (url is shadowed for godoc).
+	if u, err := parseURL(url); err == nil {
 		// If url was relative, make absolute by
 		// combining with request path.
 		// The browser would probably do this for us,
@@ -2011,39 +1992,43 @@
 			}
 
 			// no leading http://server
-			if urlStr == "" || urlStr[0] != '/' {
+			if url == "" || url[0] != '/' {
 				// make relative path absolute
 				olddir, _ := path.Split(oldpath)
-				urlStr = olddir + urlStr
+				url = olddir + url
 			}
 
 			var query string
-			if i := strings.Index(urlStr, "?"); i != -1 {
-				urlStr, query = urlStr[:i], urlStr[i:]
+			if i := strings.Index(url, "?"); i != -1 {
+				url, query = url[:i], url[i:]
 			}
 
 			// clean up but preserve trailing slash
-			trailing := strings.HasSuffix(urlStr, "/")
-			urlStr = path.Clean(urlStr)
-			if trailing && !strings.HasSuffix(urlStr, "/") {
-				urlStr += "/"
+			trailing := strings.HasSuffix(url, "/")
+			url = path.Clean(url)
+			if trailing && !strings.HasSuffix(url, "/") {
+				url += "/"
 			}
-			urlStr += query
+			url += query
 		}
 	}
 
-	w.Header().Set("Location", hexEscapeNonASCII(urlStr))
+	w.Header().Set("Location", hexEscapeNonASCII(url))
 	w.WriteHeader(code)
 
 	// RFC 2616 recommends that a short note "SHOULD" be included in the
 	// response because older user agents may not understand 301/307.
 	// Shouldn't send the response for POST or HEAD; that leaves GET.
 	if r.Method == "GET" {
-		note := "<a href=\"" + htmlEscape(urlStr) + "\">" + statusText[code] + "</a>.\n"
+		note := "<a href=\"" + htmlEscape(url) + "\">" + statusText[code] + "</a>.\n"
 		fmt.Fprintln(w, note)
 	}
 }
 
+// parseURL is just url.Parse. It exists only so that url.Parse can be called
+// in places where url is shadowed for godoc. See https://golang.org/cl/49930.
+var parseURL = url.Parse
+
 var htmlReplacer = strings.NewReplacer(
 	"&", "&amp;",
 	"<", "&lt;",
@@ -2163,9 +2148,29 @@
 	return np
 }
 
-// Find a handler on a handler map given a path string
-// Most-specific (longest) pattern wins
+// stripHostPort returns h without any trailing ":<port>".
+func stripHostPort(h string) string {
+	// If no port on host, return unchanged
+	if strings.IndexByte(h, ':') == -1 {
+		return h
+	}
+	host, _, err := net.SplitHostPort(h)
+	if err != nil {
+		return h // on error, return unchanged
+	}
+	return host
+}
+
+// Find a handler on a handler map given a path string.
+// Most-specific (longest) pattern wins.
 func (mux *ServeMux) match(path string) (h Handler, pattern string) {
+	// Check for exact match first.
+	v, ok := mux.m[path]
+	if ok {
+		return v.h, v.pattern
+	}
+
+	// Check for longest valid match.
 	var n = 0
 	for k, v := range mux.m {
 		if !pathMatch(k, path) {
@@ -2184,7 +2189,10 @@
 // consulting r.Method, r.Host, and r.URL.Path. It always returns
 // a non-nil handler. If the path is not in its canonical form, the
 // handler will be an internally-generated handler that redirects
-// to the canonical path.
+// to the canonical path. If the host contains a port, it is ignored
+// when matching handlers.
+//
+// The path and host are used unchanged for CONNECT requests.
 //
 // Handler also returns the registered pattern that matches the
 // request or, in the case of internally-generated redirects,
@@ -2193,16 +2201,24 @@
 // If there is no registered handler that applies to the request,
 // Handler returns a ``page not found'' handler and an empty pattern.
 func (mux *ServeMux) Handler(r *Request) (h Handler, pattern string) {
-	if r.Method != "CONNECT" {
-		if p := cleanPath(r.URL.Path); p != r.URL.Path {
-			_, pattern = mux.handler(r.Host, p)
-			url := *r.URL
-			url.Path = p
-			return RedirectHandler(url.String(), StatusMovedPermanently), pattern
-		}
+
+	// CONNECT requests are not canonicalized.
+	if r.Method == "CONNECT" {
+		return mux.handler(r.Host, r.URL.Path)
 	}
 
-	return mux.handler(r.Host, r.URL.Path)
+	// All other requests have any port stripped and path cleaned
+	// before passing to mux.handler.
+	host := stripHostPort(r.Host)
+	path := cleanPath(r.URL.Path)
+	if path != r.URL.Path {
+		_, pattern = mux.handler(host, path)
+		url := *r.URL
+		url.Path = path
+		return RedirectHandler(url.String(), StatusMovedPermanently), pattern
+	}
+
+	return mux.handler(host, r.URL.Path)
 }
 
 // handler is the main implementation of Handler.
@@ -2307,12 +2323,27 @@
 	return srv.Serve(l)
 }
 
+// Serve accepts incoming HTTPS connections on the listener l,
+// creating a new service goroutine for each. The service goroutines
+// read requests and then call handler to reply to them.
+//
+// Handler is typically nil, in which case the DefaultServeMux is used.
+//
+// Additionally, files containing a certificate and matching private key
+// for the server must be provided. If the certificate is signed by a
+// certificate authority, the certFile should be the concatenation
+// of the server's certificate, any intermediates, and the CA's certificate.
+func ServeTLS(l net.Listener, handler Handler, certFile, keyFile string) error {
+	srv := &Server{Handler: handler}
+	return srv.ServeTLS(l, certFile, keyFile)
+}
+
 // A Server defines parameters for running an HTTP server.
 // The zero value for Server is a valid configuration.
 type Server struct {
 	Addr      string      // TCP address to listen on, ":http" if empty
 	Handler   Handler     // handler to invoke, http.DefaultServeMux if nil
-	TLSConfig *tls.Config // optional TLS config, used by ListenAndServeTLS
+	TLSConfig *tls.Config // optional TLS config, used by ServeTLS and ListenAndServeTLS
 
 	// ReadTimeout is the maximum duration for reading the entire
 	// request, including the body.
@@ -2338,7 +2369,7 @@
 	// IdleTimeout is the maximum amount of time to wait for the
 	// next request when keep-alives are enabled. If IdleTimeout
 	// is zero, the value of ReadTimeout is used. If both are
-	// zero, there is no timeout.
+	// zero, ReadHeaderTimeout is used.
 	IdleTimeout time.Duration
 
 	// MaxHeaderBytes controls the maximum number of bytes the
@@ -2379,6 +2410,7 @@
 	listeners  map[net.Listener]struct{}
 	activeConn map[*conn]struct{}
 	doneChan   chan struct{}
+	onShutdown []func()
 }
 
 func (s *Server) getDoneChan() <-chan struct{} {
@@ -2441,7 +2473,12 @@
 // listeners, then closing all idle connections, and then waiting
 // indefinitely for connections to return to idle and then shut down.
 // If the provided context expires before the shutdown is complete,
-// then the context's error is returned.
+// Shutdown returns the context's error, otherwise it returns any
+// error returned from closing the Server's underlying Listener(s).
+//
+// When Shutdown is called, Serve, ListenAndServe, and
+// ListenAndServeTLS immediately return ErrServerClosed. Make sure the
+// program doesn't exit and waits instead for Shutdown to return.
 //
 // Shutdown does not attempt to close nor wait for hijacked
 // connections such as WebSockets. The caller of Shutdown should
@@ -2454,6 +2491,9 @@
 	srv.mu.Lock()
 	lnerr := srv.closeListenersLocked()
 	srv.closeDoneChanLocked()
+	for _, f := range srv.onShutdown {
+		go f()
+	}
 	srv.mu.Unlock()
 
 	ticker := time.NewTicker(shutdownPollInterval)
@@ -2470,6 +2510,17 @@
 	}
 }
 
+// RegisterOnShutdown registers a function to call on Shutdown.
+// This can be used to gracefully shutdown connections that have
+// undergone NPN/ALPN protocol upgrade or that have been hijacked.
+// This function should start protocol-specific graceful shutdown,
+// but should not wait for shutdown to complete.
+func (srv *Server) RegisterOnShutdown(f func()) {
+	srv.mu.Lock()
+	srv.onShutdown = append(srv.onShutdown, f)
+	srv.mu.Unlock()
+}
+
 // closeIdleConns closes all idle connections and reports whether the
 // server is quiescent.
 func (s *Server) closeIdleConns() bool {
@@ -2609,6 +2660,8 @@
 	return strSliceContains(srv.TLSConfig.NextProtos, http2NextProtoTLS)
 }
 
+// ErrServerClosed is returned by the Server's Serve, ServeTLS, ListenAndServe,
+// and ListenAndServeTLS methods after a call to Shutdown or Close.
 var ErrServerClosed = errors.New("http: Server closed")
 
 // Serve accepts incoming connections on the Listener l, creating a
@@ -2638,7 +2691,6 @@
 
 	baseCtx := context.Background() // base is always background, per Issue 16220
 	ctx := context.WithValue(baseCtx, ServerContextKey, srv)
-	ctx = context.WithValue(ctx, LocalAddrContextKey, l.Addr())
 	for {
 		rw, e := l.Accept()
 		if e != nil {
@@ -2669,6 +2721,49 @@
 	}
 }
 
+// ServeTLS accepts incoming connections on the Listener l, creating a
+// new service goroutine for each. The service goroutines read requests and
+// then call srv.Handler to reply to them.
+//
+// Additionally, files containing a certificate and matching private key for
+// the server must be provided if neither the Server's TLSConfig.Certificates
+// nor TLSConfig.GetCertificate are populated.. If the certificate is signed by
+// a certificate authority, the certFile should be the concatenation of the
+// server's certificate, any intermediates, and the CA's certificate.
+//
+// For HTTP/2 support, srv.TLSConfig should be initialized to the
+// provided listener's TLS Config before calling Serve. If
+// srv.TLSConfig is non-nil and doesn't include the string "h2" in
+// Config.NextProtos, HTTP/2 support is not enabled.
+//
+// ServeTLS always returns a non-nil error. After Shutdown or Close, the
+// returned error is ErrServerClosed.
+func (srv *Server) ServeTLS(l net.Listener, certFile, keyFile string) error {
+	// Setup HTTP/2 before srv.Serve, to initialize srv.TLSConfig
+	// before we clone it and create the TLS Listener.
+	if err := srv.setupHTTP2_ServeTLS(); err != nil {
+		return err
+	}
+
+	config := cloneTLSConfig(srv.TLSConfig)
+	if !strSliceContains(config.NextProtos, "http/1.1") {
+		config.NextProtos = append(config.NextProtos, "http/1.1")
+	}
+
+	configHasCert := len(config.Certificates) > 0 || config.GetCertificate != nil
+	if !configHasCert || certFile != "" || keyFile != "" {
+		var err error
+		config.Certificates = make([]tls.Certificate, 1)
+		config.Certificates[0], err = tls.LoadX509KeyPair(certFile, keyFile)
+		if err != nil {
+			return err
+		}
+	}
+
+	tlsListener := tls.NewListener(l, config)
+	return srv.Serve(tlsListener)
+}
+
 func (s *Server) trackListener(ln net.Listener, add bool) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -2840,47 +2935,25 @@
 		addr = ":https"
 	}
 
-	// Setup HTTP/2 before srv.Serve, to initialize srv.TLSConfig
-	// before we clone it and create the TLS Listener.
-	if err := srv.setupHTTP2_ListenAndServeTLS(); err != nil {
-		return err
-	}
-
-	config := cloneTLSConfig(srv.TLSConfig)
-	if !strSliceContains(config.NextProtos, "http/1.1") {
-		config.NextProtos = append(config.NextProtos, "http/1.1")
-	}
-
-	configHasCert := len(config.Certificates) > 0 || config.GetCertificate != nil
-	if !configHasCert || certFile != "" || keyFile != "" {
-		var err error
-		config.Certificates = make([]tls.Certificate, 1)
-		config.Certificates[0], err = tls.LoadX509KeyPair(certFile, keyFile)
-		if err != nil {
-			return err
-		}
-	}
-
 	ln, err := net.Listen("tcp", addr)
 	if err != nil {
 		return err
 	}
 
-	tlsListener := tls.NewListener(tcpKeepAliveListener{ln.(*net.TCPListener)}, config)
-	return srv.Serve(tlsListener)
+	return srv.ServeTLS(tcpKeepAliveListener{ln.(*net.TCPListener)}, certFile, keyFile)
 }
 
-// setupHTTP2_ListenAndServeTLS conditionally configures HTTP/2 on
+// setupHTTP2_ServeTLS conditionally configures HTTP/2 on
 // srv and returns whether there was an error setting it up. If it is
 // not configured for policy reasons, nil is returned.
-func (srv *Server) setupHTTP2_ListenAndServeTLS() error {
+func (srv *Server) setupHTTP2_ServeTLS() error {
 	srv.nextProtoOnce.Do(srv.onceSetNextProtoDefaults)
 	return srv.nextProtoErr
 }
 
 // setupHTTP2_Serve is called from (*Server).Serve and conditionally
 // configures HTTP/2 on srv using a more conservative policy than
-// setupHTTP2_ListenAndServeTLS because Serve may be called
+// setupHTTP2_ServeTLS because Serve may be called
 // concurrently.
 //
 // The tests named TestTransportAutomaticHTTP2* and
@@ -2907,7 +2980,10 @@
 	// Enable HTTP/2 by default if the user hasn't otherwise
 	// configured their TLSNextProto map.
 	if srv.TLSNextProto == nil {
-		srv.nextProtoErr = http2ConfigureServer(srv, nil)
+		conf := &http2Server{
+			NewWriteScheduler: func() http2WriteScheduler { return http2NewPriorityWriteScheduler(nil) },
+		}
+		srv.nextProtoErr = http2ConfigureServer(srv, conf)
 	}
 }
 
diff --git a/libgo/go/net/http/sniff.go b/libgo/go/net/http/sniff.go
index 0d21b44..ecc65e4 100644
--- a/libgo/go/net/http/sniff.go
+++ b/libgo/go/net/http/sniff.go
@@ -107,8 +107,8 @@
 		ct:   "audio/basic",
 	},
 	&maskedSig{
-		mask: []byte("OggS\x00"),
-		pat:  []byte("\x4F\x67\x67\x53\x00"),
+		mask: []byte("\xFF\xFF\xFF\xFF\xFF"),
+		pat:  []byte("OggS\x00"),
 		ct:   "application/ogg",
 	},
 	&maskedSig{
diff --git a/libgo/go/net/http/sniff_test.go b/libgo/go/net/http/sniff_test.go
index 38f3f81..24f1298 100644
--- a/libgo/go/net/http/sniff_test.go
+++ b/libgo/go/net/http/sniff_test.go
@@ -45,7 +45,11 @@
 	{"WAV audio #1", []byte("RIFFb\xb8\x00\x00WAVEfmt \x12\x00\x00\x00\x06"), "audio/wave"},
 	{"WAV audio #2", []byte("RIFF,\x00\x00\x00WAVEfmt \x12\x00\x00\x00\x06"), "audio/wave"},
 	{"AIFF audio #1", []byte("FORM\x00\x00\x00\x00AIFFCOMM\x00\x00\x00\x12\x00\x01\x00\x00\x57\x55\x00\x10\x40\x0d\xf3\x34"), "audio/aiff"},
+
 	{"OGG audio", []byte("OggS\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x7e\x46\x00\x00\x00\x00\x00\x00\x1f\xf6\xb4\xfc\x01\x1e\x01\x76\x6f\x72"), "application/ogg"},
+	{"Must not match OGG", []byte("owow\x00"), "application/octet-stream"},
+	{"Must not match OGG", []byte("oooS\x00"), "application/octet-stream"},
+	{"Must not match OGG", []byte("oggS\x00"), "application/octet-stream"},
 
 	// Video types.
 	{"MP4 video", []byte("\x00\x00\x00\x18ftypmp42\x00\x00\x00\x00mp42isom<\x06t\xbfmdat"), "video/mp4"},
diff --git a/libgo/go/net/http/transfer.go b/libgo/go/net/http/transfer.go
index 4f47637..8faff2d 100644
--- a/libgo/go/net/http/transfer.go
+++ b/libgo/go/net/http/transfer.go
@@ -51,6 +51,19 @@
 	return 1, io.EOF
 }
 
+// transferBodyReader is an io.Reader that reads from tw.Body
+// and records any non-EOF error in tw.bodyReadError.
+// It is exactly 1 pointer wide to avoid allocations into interfaces.
+type transferBodyReader struct{ tw *transferWriter }
+
+func (br transferBodyReader) Read(p []byte) (n int, err error) {
+	n, err = br.tw.Body.Read(p)
+	if err != nil && err != io.EOF {
+		br.tw.bodyReadError = err
+	}
+	return
+}
+
 // transferWriter inspects the fields of a user-supplied Request or Response,
 // sanitizes them without changing the user object and provides methods for
 // writing the respective header, body and trailer in wire format.
@@ -62,8 +75,10 @@
 	ContentLength    int64 // -1 means unknown, 0 means exactly none
 	Close            bool
 	TransferEncoding []string
+	Header           Header
 	Trailer          Header
 	IsResponse       bool
+	bodyReadError    error // any non-EOF error from reading Body
 
 	FlushHeaders bool            // flush headers to network before body
 	ByteReadCh   chan readResult // non-nil if probeRequestBody called
@@ -82,14 +97,15 @@
 		t.Method = valueOrDefault(rr.Method, "GET")
 		t.Close = rr.Close
 		t.TransferEncoding = rr.TransferEncoding
+		t.Header = rr.Header
 		t.Trailer = rr.Trailer
-		atLeastHTTP11 = rr.protoAtLeastOutgoing(1, 1)
 		t.Body = rr.Body
 		t.BodyCloser = rr.Body
 		t.ContentLength = rr.outgoingLength()
-		if t.ContentLength < 0 && len(t.TransferEncoding) == 0 && atLeastHTTP11 && t.shouldSendChunkedRequestBody() {
+		if t.ContentLength < 0 && len(t.TransferEncoding) == 0 && t.shouldSendChunkedRequestBody() {
 			t.TransferEncoding = []string{"chunked"}
 		}
+		atLeastHTTP11 = true // Transport requests are always 1.1 or 2.0
 	case *Response:
 		t.IsResponse = true
 		if rr.Request != nil {
@@ -100,6 +116,7 @@
 		t.ContentLength = rr.ContentLength
 		t.Close = rr.Close
 		t.TransferEncoding = rr.TransferEncoding
+		t.Header = rr.Header
 		t.Trailer = rr.Trailer
 		atLeastHTTP11 = rr.ProtoAtLeast(1, 1)
 		t.ResponseToHEAD = noResponseBodyExpected(t.Method)
@@ -252,7 +269,7 @@
 }
 
 func (t *transferWriter) WriteHeader(w io.Writer) error {
-	if t.Close {
+	if t.Close && !hasToken(t.Header.get("Connection"), "close") {
 		if _, err := io.WriteString(w, "Connection: close\r\n"); err != nil {
 			return err
 		}
@@ -304,24 +321,25 @@
 
 	// Write body
 	if t.Body != nil {
+		var body = transferBodyReader{t}
 		if chunked(t.TransferEncoding) {
 			if bw, ok := w.(*bufio.Writer); ok && !t.IsResponse {
 				w = &internal.FlushAfterChunkWriter{Writer: bw}
 			}
 			cw := internal.NewChunkedWriter(w)
-			_, err = io.Copy(cw, t.Body)
+			_, err = io.Copy(cw, body)
 			if err == nil {
 				err = cw.Close()
 			}
 		} else if t.ContentLength == -1 {
-			ncopy, err = io.Copy(w, t.Body)
+			ncopy, err = io.Copy(w, body)
 		} else {
-			ncopy, err = io.Copy(w, io.LimitReader(t.Body, t.ContentLength))
+			ncopy, err = io.Copy(w, io.LimitReader(body, t.ContentLength))
 			if err != nil {
 				return err
 			}
 			var nextra int64
-			nextra, err = io.Copy(ioutil.Discard, t.Body)
+			nextra, err = io.Copy(ioutil.Discard, body)
 			ncopy += nextra
 		}
 		if err != nil {
diff --git a/libgo/go/net/http/transport.go b/libgo/go/net/http/transport.go
index 571943d..6a89392 100644
--- a/libgo/go/net/http/transport.go
+++ b/libgo/go/net/http/transport.go
@@ -29,6 +29,7 @@
 	"time"
 
 	"golang_org/x/net/lex/httplex"
+	"golang_org/x/net/proxy"
 )
 
 // DefaultTransport is the default implementation of Transport and is
@@ -88,6 +89,11 @@
 	// Proxy specifies a function to return a proxy for a given
 	// Request. If the function returns a non-nil error, the
 	// request is aborted with the provided error.
+	//
+	// The proxy type is determined by the URL scheme. "http"
+	// and "socks5" are supported. If the scheme is empty,
+	// "http" is assumed.
+	//
 	// If Proxy is nil or returns a nil *URL, no proxy is used.
 	Proxy func(*Request) (*url.URL, error)
 
@@ -275,13 +281,17 @@
 		return nil, nil
 	}
 	proxyURL, err := url.Parse(proxy)
-	if err != nil || !strings.HasPrefix(proxyURL.Scheme, "http") {
+	if err != nil ||
+		(proxyURL.Scheme != "http" &&
+			proxyURL.Scheme != "https" &&
+			proxyURL.Scheme != "socks5") {
 		// proxy was bogus. Try prepending "http://" to it and
 		// see if that parses correctly. If not, we fall
 		// through and complain about the original one.
 		if proxyURL, err := url.Parse("http://" + proxy); err == nil {
 			return proxyURL, nil
 		}
+
 	}
 	if err != nil {
 		return nil, fmt.Errorf("invalid proxy address %q: %v", proxy, err)
@@ -298,11 +308,15 @@
 }
 
 // transportRequest is a wrapper around a *Request that adds
-// optional extra headers to write.
+// optional extra headers to write and stores any error to return
+// from roundTrip.
 type transportRequest struct {
 	*Request                        // original request, not to be mutated
 	extra    Header                 // extra headers to write, or nil
 	trace    *httptrace.ClientTrace // optional
+
+	mu  sync.Mutex // guards err
+	err error      // first setError value for mapRoundTripError to consider
 }
 
 func (tr *transportRequest) extraHeaders() Header {
@@ -312,6 +326,14 @@
 	return tr.extra
 }
 
+func (tr *transportRequest) setError(err error) {
+	tr.mu.Lock()
+	if tr.err == nil {
+		tr.err = err
+	}
+	tr.mu.Unlock()
+}
+
 // RoundTrip implements the RoundTripper interface.
 //
 // For higher-level HTTP client support (such as handling of cookies
@@ -402,6 +424,18 @@
 			return nil, err
 		}
 		testHookRoundTripRetried()
+
+		// Rewind the body if we're able to.  (HTTP/2 does this itself so we only
+		// need to do it for HTTP/1.1 connections.)
+		if req.GetBody != nil && pconn.alt == nil {
+			newReq := *req
+			var err error
+			newReq.Body, err = req.GetBody()
+			if err != nil {
+				return nil, err
+			}
+			req = &newReq
+		}
 	}
 }
 
@@ -433,8 +467,9 @@
 		return false
 	}
 	if _, ok := err.(nothingWrittenError); ok {
-		// We never wrote anything, so it's safe to retry.
-		return true
+		// We never wrote anything, so it's safe to retry, if there's no body or we
+		// can "rewind" the body with GetBody.
+		return req.outgoingLength() == 0 || req.GetBody != nil
 	}
 	if !req.isReplayable() {
 		// Don't retry non-idempotent requests.
@@ -788,7 +823,7 @@
 	}
 	t.idleLRU.remove(pconn)
 	key := pconn.cacheKey
-	pconns, _ := t.idleConn[key]
+	pconns := t.idleConn[key]
 	switch len(pconns) {
 	case 0:
 		// Nothing
@@ -964,6 +999,23 @@
 	}
 }
 
+type oneConnDialer <-chan net.Conn
+
+func newOneConnDialer(c net.Conn) proxy.Dialer {
+	ch := make(chan net.Conn, 1)
+	ch <- c
+	return oneConnDialer(ch)
+}
+
+func (d oneConnDialer) Dial(network, addr string) (net.Conn, error) {
+	select {
+	case c := <-d:
+		return c, nil
+	default:
+		return nil, io.EOF
+	}
+}
+
 func (t *Transport) dialConn(ctx context.Context, cm connectMethod) (*persistConn, error) {
 	pconn := &persistConn{
 		t:             t,
@@ -1020,6 +1072,23 @@
 	switch {
 	case cm.proxyURL == nil:
 		// Do nothing. Not using a proxy.
+	case cm.proxyURL.Scheme == "socks5":
+		conn := pconn.conn
+		var auth *proxy.Auth
+		if u := cm.proxyURL.User; u != nil {
+			auth = &proxy.Auth{}
+			auth.User = u.Username()
+			auth.Password, _ = u.Password()
+		}
+		p, err := proxy.SOCKS5("", cm.addr(), auth, newOneConnDialer(conn))
+		if err != nil {
+			conn.Close()
+			return nil, err
+		}
+		if _, err := p.Dial("tcp", cm.targetAddr); err != nil {
+			conn.Close()
+			return nil, err
+		}
 	case cm.targetScheme == "http":
 		pconn.isProxy = true
 		if pa := cm.proxyAuth(); pa != "" {
@@ -1176,6 +1245,10 @@
 		if addr == p {
 			return false
 		}
+		if len(p) == 0 {
+			// There is no host part, likely the entry is malformed; ignore.
+			continue
+		}
 		if p[0] == '.' && (strings.HasSuffix(addr, p) || addr == p[1:]) {
 			// no_proxy ".foo.com" matches "bar.foo.com" or "foo.com"
 			return false
@@ -1193,19 +1266,21 @@
 //
 // A connect method may be of the following types:
 //
-// Cache key form                Description
-// -----------------             -------------------------
-// |http|foo.com                 http directly to server, no proxy
-// |https|foo.com                https directly to server, no proxy
-// http://proxy.com|https|foo.com  http to proxy, then CONNECT to foo.com
-// http://proxy.com|http           http to proxy, http to anywhere after that
+// Cache key form                    Description
+// -----------------                 -------------------------
+// |http|foo.com                     http directly to server, no proxy
+// |https|foo.com                    https directly to server, no proxy
+// http://proxy.com|https|foo.com    http to proxy, then CONNECT to foo.com
+// http://proxy.com|http             http to proxy, http to anywhere after that
+// socks5://proxy.com|http|foo.com   socks5 to proxy, then http to foo.com
+// socks5://proxy.com|https|foo.com  socks5 to proxy, then https to foo.com
 //
 // Note: no support to https to the proxy yet.
 //
 type connectMethod struct {
 	proxyURL     *url.URL // nil for no proxy, else full proxy URL
 	targetScheme string   // "http" or "https"
-	targetAddr   string   // Not used if proxy + http targetScheme (4th example in table)
+	targetAddr   string   // Not used if http proxy + http targetScheme (4th example in table)
 }
 
 func (cm *connectMethod) key() connectMethodKey {
@@ -1213,7 +1288,7 @@
 	targetAddr := cm.targetAddr
 	if cm.proxyURL != nil {
 		proxyStr = cm.proxyURL.String()
-		if cm.targetScheme == "http" {
+		if strings.HasPrefix(cm.proxyURL.Scheme, "http") && cm.targetScheme == "http" {
 			targetAddr = ""
 		}
 	}
@@ -1379,63 +1454,53 @@
 	pc.close(errIdleConnTimeout)
 }
 
-// mapRoundTripErrorFromReadLoop maps the provided readLoop error into
-// the error value that should be returned from persistConn.roundTrip.
+// mapRoundTripError returns the appropriate error value for
+// persistConn.roundTrip.
+//
+// The provided err is the first error that (*persistConn).roundTrip
+// happened to receive from its select statement.
 //
 // The startBytesWritten value should be the value of pc.nwrite before the roundTrip
 // started writing the request.
-func (pc *persistConn) mapRoundTripErrorFromReadLoop(req *Request, startBytesWritten int64, err error) (out error) {
+func (pc *persistConn) mapRoundTripError(req *transportRequest, startBytesWritten int64, err error) error {
 	if err == nil {
 		return nil
 	}
-	if err := pc.canceled(); err != nil {
-		return err
+
+	// If the request was canceled, that's better than network
+	// failures that were likely the result of tearing down the
+	// connection.
+	if cerr := pc.canceled(); cerr != nil {
+		return cerr
 	}
+
+	// See if an error was set explicitly.
+	req.mu.Lock()
+	reqErr := req.err
+	req.mu.Unlock()
+	if reqErr != nil {
+		return reqErr
+	}
+
 	if err == errServerClosedIdle {
+		// Don't decorate
 		return err
 	}
+
 	if _, ok := err.(transportReadFromServerError); ok {
+		// Don't decorate
 		return err
 	}
 	if pc.isBroken() {
 		<-pc.writeLoopDone
-		if pc.nwrite == startBytesWritten && req.outgoingLength() == 0 {
+		if pc.nwrite == startBytesWritten {
 			return nothingWrittenError{err}
 		}
+		return fmt.Errorf("net/http: HTTP/1.x transport connection broken: %v", err)
 	}
 	return err
 }
 
-// mapRoundTripErrorAfterClosed returns the error value to be propagated
-// up to Transport.RoundTrip method when persistConn.roundTrip sees
-// its pc.closech channel close, indicating the persistConn is dead.
-// (after closech is closed, pc.closed is valid).
-func (pc *persistConn) mapRoundTripErrorAfterClosed(req *Request, startBytesWritten int64) error {
-	if err := pc.canceled(); err != nil {
-		return err
-	}
-	err := pc.closed
-	if err == errServerClosedIdle {
-		// Don't decorate
-		return err
-	}
-	if _, ok := err.(transportReadFromServerError); ok {
-		// Don't decorate
-		return err
-	}
-
-	// Wait for the writeLoop goroutine to terminated, and then
-	// see if we actually managed to write anything. If not, we
-	// can retry the request.
-	<-pc.writeLoopDone
-	if pc.nwrite == startBytesWritten && req.outgoingLength() == 0 {
-		return nothingWrittenError{err}
-	}
-
-	return fmt.Errorf("net/http: HTTP/1.x transport connection broken: %v", err)
-
-}
-
 func (pc *persistConn) readLoop() {
 	closeErr := errReadLoopExiting // default value, if not changed below
 	defer func() {
@@ -1497,16 +1562,6 @@
 				err = fmt.Errorf("net/http: server response headers exceeded %d bytes; aborted", pc.maxHeaderResponseSize())
 			}
 
-			// If we won't be able to retry this request later (from the
-			// roundTrip goroutine), mark it as done now.
-			// BEFORE the send on rc.ch, as the client might re-use the
-			// same *Request pointer, and we don't want to set call
-			// t.setReqCanceler from this persistConn while the Transport
-			// potentially spins up a different persistConn for the
-			// caller's subsequent request.
-			if !pc.shouldRetryRequest(rc.req, err) {
-				pc.t.setReqCanceler(rc.req, nil)
-			}
 			select {
 			case rc.ch <- responseAndError{err: err}:
 			case <-rc.callerGone:
@@ -1579,7 +1634,7 @@
 		}
 
 		resp.Body = body
-		if rc.addedGzip && resp.Header.Get("Content-Encoding") == "gzip" {
+		if rc.addedGzip && strings.EqualFold(resp.Header.Get("Content-Encoding"), "gzip") {
 			resp.Body = &gzipReader{body: body}
 			resp.Header.Del("Content-Encoding")
 			resp.Header.Del("Content-Length")
@@ -1705,12 +1760,23 @@
 		case wr := <-pc.writech:
 			startBytesWritten := pc.nwrite
 			err := wr.req.Request.write(pc.bw, pc.isProxy, wr.req.extra, pc.waitForContinue(wr.continueCh))
+			if bre, ok := err.(requestBodyReadError); ok {
+				err = bre.error
+				// Errors reading from the user's
+				// Request.Body are high priority.
+				// Set it here before sending on the
+				// channels below or calling
+				// pc.close() which tears town
+				// connections and causes other
+				// errors.
+				wr.req.setError(err)
+			}
 			if err == nil {
 				err = pc.bw.Flush()
 			}
 			if err != nil {
 				wr.req.Request.closeBody()
-				if pc.nwrite == startBytesWritten && wr.req.outgoingLength() == 0 {
+				if pc.nwrite == startBytesWritten {
 					err = nothingWrittenError{err}
 				}
 			}
@@ -1872,6 +1938,14 @@
 	gone := make(chan struct{})
 	defer close(gone)
 
+	defer func() {
+		if err != nil {
+			pc.t.setReqCanceler(req.Request, nil)
+		}
+	}()
+
+	const debugRoundTrip = false
+
 	// Write the request concurrently with waiting for a response,
 	// in case the server decides to reply before reading our full
 	// request body.
@@ -1888,38 +1962,50 @@
 		callerGone: gone,
 	}
 
-	var re responseAndError
 	var respHeaderTimer <-chan time.Time
 	cancelChan := req.Request.Cancel
 	ctxDoneChan := req.Context().Done()
-WaitResponse:
 	for {
 		testHookWaitResLoop()
 		select {
 		case err := <-writeErrCh:
+			if debugRoundTrip {
+				req.logf("writeErrCh resv: %T/%#v", err, err)
+			}
 			if err != nil {
-				if cerr := pc.canceled(); cerr != nil {
-					err = cerr
-				}
-				re = responseAndError{err: err}
 				pc.close(fmt.Errorf("write error: %v", err))
-				break WaitResponse
+				return nil, pc.mapRoundTripError(req, startBytesWritten, err)
 			}
 			if d := pc.t.ResponseHeaderTimeout; d > 0 {
+				if debugRoundTrip {
+					req.logf("starting timer for %v", d)
+				}
 				timer := time.NewTimer(d)
 				defer timer.Stop() // prevent leaks
 				respHeaderTimer = timer.C
 			}
 		case <-pc.closech:
-			re = responseAndError{err: pc.mapRoundTripErrorAfterClosed(req.Request, startBytesWritten)}
-			break WaitResponse
+			if debugRoundTrip {
+				req.logf("closech recv: %T %#v", pc.closed, pc.closed)
+			}
+			return nil, pc.mapRoundTripError(req, startBytesWritten, pc.closed)
 		case <-respHeaderTimer:
+			if debugRoundTrip {
+				req.logf("timeout waiting for response headers.")
+			}
 			pc.close(errTimeout)
-			re = responseAndError{err: errTimeout}
-			break WaitResponse
-		case re = <-resc:
-			re.err = pc.mapRoundTripErrorFromReadLoop(req.Request, startBytesWritten, re.err)
-			break WaitResponse
+			return nil, errTimeout
+		case re := <-resc:
+			if (re.res == nil) == (re.err == nil) {
+				panic(fmt.Sprintf("internal error: exactly one of res or err should be set; nil=%v", re.res == nil))
+			}
+			if debugRoundTrip {
+				req.logf("resc recv: %p, %T/%#v", re.res, re.err, re.err)
+			}
+			if re.err != nil {
+				return nil, pc.mapRoundTripError(req, startBytesWritten, re.err)
+			}
+			return re.res, nil
 		case <-cancelChan:
 			pc.t.CancelRequest(req.Request)
 			cancelChan = nil
@@ -1929,14 +2015,16 @@
 			ctxDoneChan = nil
 		}
 	}
+}
 
-	if re.err != nil {
-		pc.t.setReqCanceler(req.Request, nil)
+// tLogKey is a context WithValue key for test debugging contexts containing
+// a t.Logf func. See export_test.go's Request.WithT method.
+type tLogKey struct{}
+
+func (r *transportRequest) logf(format string, args ...interface{}) {
+	if logf, ok := r.Request.Context().Value(tLogKey{}).(func(string, ...interface{})); ok {
+		logf(time.Now().Format(time.RFC3339Nano)+": "+format, args...)
 	}
-	if (re.res == nil) == (re.err == nil) {
-		panic("internal error: exactly one of res or err should be set")
-	}
-	return re.res, re.err
 }
 
 // markReused marks this connection as having been successfully used for a
@@ -1982,8 +2070,9 @@
 }
 
 var portMap = map[string]string{
-	"http":  "80",
-	"https": "443",
+	"http":   "80",
+	"https":  "443",
+	"socks5": "1080",
 }
 
 // canonicalAddr returns url.Host but always with a ":port" suffix
diff --git a/libgo/go/net/http/transport_internal_test.go b/libgo/go/net/http/transport_internal_test.go
index 3d24fc1..594bf6e 100644
--- a/libgo/go/net/http/transport_internal_test.go
+++ b/libgo/go/net/http/transport_internal_test.go
@@ -9,6 +9,7 @@
 import (
 	"errors"
 	"net"
+	"strings"
 	"testing"
 )
 
@@ -30,6 +31,7 @@
 
 	tr := new(Transport)
 	req, _ := NewRequest("GET", "http://"+ln.Addr().String(), nil)
+	req = req.WithT(t)
 	treq := &transportRequest{Request: req}
 	cm := connectMethod{targetScheme: "http", targetAddr: ln.Addr().String()}
 	pc, err := tr.getConn(treq, cm)
@@ -47,13 +49,13 @@
 
 	_, err = pc.roundTrip(treq)
 	if !isTransportReadFromServerError(err) && err != errServerClosedIdle {
-		t.Fatalf("roundTrip = %#v, %v; want errServerClosedConn or errServerClosedIdle", err, err)
+		t.Errorf("roundTrip = %#v, %v; want errServerClosedIdle or transportReadFromServerError", err, err)
 	}
 
 	<-pc.closech
 	err = pc.closed
 	if !isTransportReadFromServerError(err) && err != errServerClosedIdle {
-		t.Fatalf("pc.closed = %#v, %v; want errServerClosedConn or errServerClosedIdle", err, err)
+		t.Errorf("pc.closed = %#v, %v; want errServerClosedIdle or transportReadFromServerError", err, err)
 	}
 }
 
@@ -80,6 +82,19 @@
 	}
 	return req
 }
+func dummyRequestWithBody(method string) *Request {
+	req, err := NewRequest(method, "http://fake.tld/", strings.NewReader("foo"))
+	if err != nil {
+		panic(err)
+	}
+	return req
+}
+
+func dummyRequestWithBodyNoGetBody(method string) *Request {
+	req := dummyRequestWithBody(method)
+	req.GetBody = nil
+	return req
+}
 
 func TestTransportShouldRetryRequest(t *testing.T) {
 	tests := []struct {
@@ -131,6 +146,18 @@
 			err:  errServerClosedIdle,
 			want: true,
 		},
+		7: {
+			pc:   &persistConn{reused: true},
+			req:  dummyRequestWithBody("POST"),
+			err:  nothingWrittenError{},
+			want: true,
+		},
+		8: {
+			pc:   &persistConn{reused: true},
+			req:  dummyRequestWithBodyNoGetBody("POST"),
+			err:  nothingWrittenError{},
+			want: false,
+		},
 	}
 	for i, tt := range tests {
 		got := tt.pc.shouldRetryRequest(tt.req, tt.err)
diff --git a/libgo/go/net/http/transport_test.go b/libgo/go/net/http/transport_test.go
index a58b183..27b55dc 100644
--- a/libgo/go/net/http/transport_test.go
+++ b/libgo/go/net/http/transport_test.go
@@ -16,6 +16,7 @@
 	"context"
 	"crypto/rand"
 	"crypto/tls"
+	"encoding/binary"
 	"errors"
 	"fmt"
 	"internal/nettrace"
@@ -130,11 +131,9 @@
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
 
+	c := ts.Client()
 	for _, disableKeepAlive := range []bool{false, true} {
-		tr := &Transport{DisableKeepAlives: disableKeepAlive}
-		defer tr.CloseIdleConnections()
-		c := &Client{Transport: tr}
-
+		c.Transport.(*Transport).DisableKeepAlives = disableKeepAlive
 		fetch := func(n int) string {
 			res, err := c.Get(ts.URL)
 			if err != nil {
@@ -165,12 +164,11 @@
 
 	connSet, testDial := makeTestDial(t)
 
-	for _, connectionClose := range []bool{false, true} {
-		tr := &Transport{
-			Dial: testDial,
-		}
-		c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
+	tr.Dial = testDial
 
+	for _, connectionClose := range []bool{false, true} {
 		fetch := func(n int) string {
 			req := new(Request)
 			var err error
@@ -216,12 +214,10 @@
 
 	connSet, testDial := makeTestDial(t)
 
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
+	tr.Dial = testDial
 	for _, connectionClose := range []bool{false, true} {
-		tr := &Transport{
-			Dial: testDial,
-		}
-		c := &Client{Transport: tr}
-
 		fetch := func(n int) string {
 			req := new(Request)
 			var err error
@@ -272,10 +268,9 @@
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
 
-	tr := &Transport{
-		DisableKeepAlives: true,
-	}
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	c.Transport.(*Transport).DisableKeepAlives = true
+
 	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatal(err)
@@ -290,9 +285,8 @@
 	defer afterTest(t)
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
-
-	tr := &Transport{DisableKeepAlives: false}
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	if e, g := 0, len(tr.IdleConnKeysForTesting()); e != g {
 		t.Errorf("After CloseIdleConnections expected %d idle conn cache keys; got %d", e, g)
@@ -384,9 +378,11 @@
 		}
 	}))
 	defer ts.Close()
+
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 	maxIdleConnsPerHost := 2
-	tr := &Transport{DisableKeepAlives: false, MaxIdleConnsPerHost: maxIdleConnsPerHost}
-	c := &Client{Transport: tr}
+	tr.MaxIdleConnsPerHost = maxIdleConnsPerHost
 
 	// Start 3 outstanding requests and wait for the server to get them.
 	// Their responses will hang until we write to resch, though.
@@ -449,9 +445,8 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	doReq := func(name string) string {
 		// Do a POST instead of a GET to prevent the Transport's
@@ -495,9 +490,7 @@
 	defer afterTest(t)
 	ts := httptest.NewServer(hostPortHandler)
 	defer ts.Close()
-
-	tr := &Transport{}
-	c := &Client{Transport: tr}
+	c := ts.Client()
 
 	fetch := func(n, retries int) string {
 		condFatalf := func(format string, arg ...interface{}) {
@@ -563,10 +556,7 @@
 		conn.Close()
 	}))
 	defer ts.Close()
-
-	tr := &Transport{DisableKeepAlives: false}
-	c := &Client{Transport: tr}
-	defer tr.CloseIdleConnections()
+	c := ts.Client()
 
 	// Do a bunch of traffic from different goroutines. Send to activityc
 	// after each request completes, regardless of whether it failed.
@@ -619,9 +609,8 @@
 		w.WriteHeader(200)
 	}))
 	defer ts.Close()
+	c := ts.Client()
 
-	tr := &Transport{DisableKeepAlives: false}
-	c := &Client{Transport: tr}
 	for i := 0; i < 2; i++ {
 		res, err := c.Head(ts.URL)
 		if err != nil {
@@ -655,10 +644,7 @@
 		w.WriteHeader(200)
 	}))
 	defer ts.Close()
-
-	tr := &Transport{DisableKeepAlives: false}
-	c := &Client{Transport: tr}
-	defer tr.CloseIdleConnections()
+	c := ts.Client()
 
 	// Ensure that we wait for the readLoop to complete before
 	// calling Head again
@@ -719,6 +705,7 @@
 		}
 	}))
 	defer ts.Close()
+	tr := ts.Client().Transport.(*Transport)
 
 	for i, test := range roundTripTests {
 		// Test basic request (no accept-encoding)
@@ -726,7 +713,7 @@
 		if test.accept != "" {
 			req.Header.Set("Accept-Encoding", test.accept)
 		}
-		res, err := DefaultTransport.RoundTrip(req)
+		res, err := tr.RoundTrip(req)
 		var body []byte
 		if test.compressed {
 			var r *gzip.Reader
@@ -791,10 +778,9 @@
 		gz.Close()
 	}))
 	defer ts.Close()
+	c := ts.Client()
 
 	for _, chunked := range []string{"1", "0"} {
-		c := &Client{Transport: &Transport{}}
-
 		// First fetch something large, but only read some of it.
 		res, err := c.Get(ts.URL + "/?body=large&chunked=" + chunked)
 		if err != nil {
@@ -844,7 +830,6 @@
 	}
 
 	// And a HEAD request too, because they're always weird.
-	c := &Client{Transport: &Transport{}}
 	res, err := c.Head(ts.URL)
 	if err != nil {
 		t.Fatalf("Head: %v", err)
@@ -914,11 +899,13 @@
 		{path: "/timeout", body: []byte("hello"), sent: 5, status: 200},   // Timeout exceeded and entire body is sent.
 	}
 
+	c := ts.Client()
 	for i, v := range tests {
-		tr := &Transport{ExpectContinueTimeout: 2 * time.Second}
+		tr := &Transport{
+			ExpectContinueTimeout: 2 * time.Second,
+		}
 		defer tr.CloseIdleConnections()
-		c := &Client{Transport: tr}
-
+		c.Transport = tr
 		body := bytes.NewReader(v.body)
 		req, err := NewRequest("PUT", ts.URL+v.path, body)
 		if err != nil {
@@ -943,6 +930,99 @@
 	}
 }
 
+func TestSocks5Proxy(t *testing.T) {
+	defer afterTest(t)
+	ch := make(chan string, 1)
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		ch <- "real server"
+	}))
+	defer ts.Close()
+	l := newLocalListener(t)
+	defer l.Close()
+	go func() {
+		defer close(ch)
+		s, err := l.Accept()
+		if err != nil {
+			t.Errorf("socks5 proxy Accept(): %v", err)
+			return
+		}
+		defer s.Close()
+		var buf [22]byte
+		if _, err := io.ReadFull(s, buf[:3]); err != nil {
+			t.Errorf("socks5 proxy initial read: %v", err)
+			return
+		}
+		if want := []byte{5, 1, 0}; !bytes.Equal(buf[:3], want) {
+			t.Errorf("socks5 proxy initial read: got %v, want %v", buf[:3], want)
+			return
+		}
+		if _, err := s.Write([]byte{5, 0}); err != nil {
+			t.Errorf("socks5 proxy initial write: %v", err)
+			return
+		}
+		if _, err := io.ReadFull(s, buf[:4]); err != nil {
+			t.Errorf("socks5 proxy second read: %v", err)
+			return
+		}
+		if want := []byte{5, 1, 0}; !bytes.Equal(buf[:3], want) {
+			t.Errorf("socks5 proxy second read: got %v, want %v", buf[:3], want)
+			return
+		}
+		var ipLen int
+		switch buf[3] {
+		case 1:
+			ipLen = 4
+		case 4:
+			ipLen = 16
+		default:
+			t.Fatalf("socks5 proxy second read: unexpected address type %v", buf[4])
+		}
+		if _, err := io.ReadFull(s, buf[4:ipLen+6]); err != nil {
+			t.Errorf("socks5 proxy address read: %v", err)
+			return
+		}
+		ip := net.IP(buf[4 : ipLen+4])
+		port := binary.BigEndian.Uint16(buf[ipLen+4 : ipLen+6])
+		copy(buf[:3], []byte{5, 0, 0})
+		if _, err := s.Write(buf[:ipLen+6]); err != nil {
+			t.Errorf("socks5 proxy connect write: %v", err)
+			return
+		}
+		done := make(chan struct{})
+		srv := &Server{Handler: HandlerFunc(func(w ResponseWriter, r *Request) {
+			done <- struct{}{}
+		})}
+		srv.Serve(&oneConnListener{conn: s})
+		<-done
+		srv.Shutdown(context.Background())
+		ch <- fmt.Sprintf("proxy for %s:%d", ip, port)
+	}()
+
+	pu, err := url.Parse("socks5://" + l.Addr().String())
+	if err != nil {
+		t.Fatal(err)
+	}
+	c := ts.Client()
+	c.Transport.(*Transport).Proxy = ProxyURL(pu)
+	if _, err := c.Head(ts.URL); err != nil {
+		t.Error(err)
+	}
+	var got string
+	select {
+	case got = <-ch:
+	case <-time.After(5 * time.Second):
+		t.Fatal("timeout connecting to socks5 proxy")
+	}
+	tsu, err := url.Parse(ts.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := "proxy for " + tsu.Host
+	if got != want {
+		t.Errorf("got %q, want %q", got, want)
+	}
+}
+
 func TestTransportProxy(t *testing.T) {
 	defer afterTest(t)
 	ch := make(chan string, 1)
@@ -959,12 +1039,20 @@
 	if err != nil {
 		t.Fatal(err)
 	}
-	c := &Client{Transport: &Transport{Proxy: ProxyURL(pu)}}
-	c.Head(ts.URL)
-	got := <-ch
+	c := ts.Client()
+	c.Transport.(*Transport).Proxy = ProxyURL(pu)
+	if _, err := c.Head(ts.URL); err != nil {
+		t.Error(err)
+	}
+	var got string
+	select {
+	case got = <-ch:
+	case <-time.After(5 * time.Second):
+		t.Fatal("timeout connecting to http proxy")
+	}
 	want := "proxy for " + ts.URL + "/"
 	if got != want {
-		t.Errorf("want %q, got %q", want, got)
+		t.Errorf("got %q, want %q", got, want)
 	}
 }
 
@@ -1022,9 +1110,7 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatal(err)
@@ -1052,9 +1138,7 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatal(err)
@@ -1095,9 +1179,8 @@
 		w.WriteHeader(204)
 	}))
 	defer ts.Close()
-
-	tr := &Transport{}
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	n0 := runtime.NumGoroutine()
 
@@ -1160,9 +1243,8 @@
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 	}))
 	defer ts.Close()
-
-	tr := &Transport{}
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	n0 := runtime.NumGoroutine()
 	body := []byte("Hello")
@@ -1194,8 +1276,7 @@
 // This used to crash; https://golang.org/issue/3266
 func TestTransportIdleConnCrash(t *testing.T) {
 	defer afterTest(t)
-	tr := &Transport{}
-	c := &Client{Transport: tr}
+	var tr *Transport
 
 	unblockCh := make(chan bool, 1)
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
@@ -1203,6 +1284,8 @@
 		tr.CloseIdleConnections()
 	}))
 	defer ts.Close()
+	c := ts.Client()
+	tr = c.Transport.(*Transport)
 
 	didreq := make(chan bool)
 	go func() {
@@ -1232,8 +1315,7 @@
 		}
 	}))
 	defer ts.Close()
-	tr := &Transport{}
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatal(err)
@@ -1258,8 +1340,7 @@
 		Error(w, deniedMsg, StatusUnauthorized)
 	}))
 	defer ts.Close()
-	tr := &Transport{}
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	res, err := c.Post(ts.URL, "application/octet-stream", neverEnding('a'))
 	if err != nil {
 		t.Errorf("Post: %v", err)
@@ -1283,8 +1364,8 @@
 	}))
 	defer ts.Close()
 
+	c := ts.Client()
 	for _, closeBody := range []bool{true, false} {
-		c := &Client{Transport: &Transport{}}
 		const n = 4
 		for i := 1; i <= n; i++ {
 			res, err := c.Get(ts.URL)
@@ -1324,10 +1405,7 @@
 	SetPendingDialHooks(func() { wg.Add(1) }, wg.Done)
 	defer SetPendingDialHooks(nil, nil)
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-
-	c := &Client{Transport: tr}
+	c := ts.Client()
 	reqs := make(chan string)
 	defer close(reqs)
 
@@ -1369,23 +1447,20 @@
 		io.Copy(w, neverEnding('a'))
 	})
 	ts := httptest.NewServer(mux)
+	defer ts.Close()
 	timeout := 100 * time.Millisecond
 
-	client := &Client{
-		Transport: &Transport{
-			Dial: func(n, addr string) (net.Conn, error) {
-				conn, err := net.Dial(n, addr)
-				if err != nil {
-					return nil, err
-				}
-				conn.SetDeadline(time.Now().Add(timeout))
-				if debug {
-					conn = NewLoggingConn("client", conn)
-				}
-				return conn, nil
-			},
-			DisableKeepAlives: true,
-		},
+	c := ts.Client()
+	c.Transport.(*Transport).Dial = func(n, addr string) (net.Conn, error) {
+		conn, err := net.Dial(n, addr)
+		if err != nil {
+			return nil, err
+		}
+		conn.SetDeadline(time.Now().Add(timeout))
+		if debug {
+			conn = NewLoggingConn("client", conn)
+		}
+		return conn, nil
 	}
 
 	getFailed := false
@@ -1397,7 +1472,7 @@
 		if debug {
 			println("run", i+1, "of", nRuns)
 		}
-		sres, err := client.Get(ts.URL + "/get")
+		sres, err := c.Get(ts.URL + "/get")
 		if err != nil {
 			if !getFailed {
 				// Make the timeout longer, once.
@@ -1419,7 +1494,6 @@
 	if debug {
 		println("tests complete; waiting for handlers to finish")
 	}
-	ts.Close()
 }
 
 func TestIssue4191_InfiniteGetToPutTimeout(t *testing.T) {
@@ -1437,21 +1511,17 @@
 	ts := httptest.NewServer(mux)
 	timeout := 100 * time.Millisecond
 
-	client := &Client{
-		Transport: &Transport{
-			Dial: func(n, addr string) (net.Conn, error) {
-				conn, err := net.Dial(n, addr)
-				if err != nil {
-					return nil, err
-				}
-				conn.SetDeadline(time.Now().Add(timeout))
-				if debug {
-					conn = NewLoggingConn("client", conn)
-				}
-				return conn, nil
-			},
-			DisableKeepAlives: true,
-		},
+	c := ts.Client()
+	c.Transport.(*Transport).Dial = func(n, addr string) (net.Conn, error) {
+		conn, err := net.Dial(n, addr)
+		if err != nil {
+			return nil, err
+		}
+		conn.SetDeadline(time.Now().Add(timeout))
+		if debug {
+			conn = NewLoggingConn("client", conn)
+		}
+		return conn, nil
 	}
 
 	getFailed := false
@@ -1463,7 +1533,7 @@
 		if debug {
 			println("run", i+1, "of", nRuns)
 		}
-		sres, err := client.Get(ts.URL + "/get")
+		sres, err := c.Get(ts.URL + "/get")
 		if err != nil {
 			if !getFailed {
 				// Make the timeout longer, once.
@@ -1477,7 +1547,7 @@
 			break
 		}
 		req, _ := NewRequest("PUT", ts.URL+"/put", sres.Body)
-		_, err = client.Do(req)
+		_, err = c.Do(req)
 		if err == nil {
 			sres.Body.Close()
 			t.Errorf("Unexpected successful PUT")
@@ -1509,11 +1579,8 @@
 	ts := httptest.NewServer(mux)
 	defer ts.Close()
 
-	tr := &Transport{
-		ResponseHeaderTimeout: 500 * time.Millisecond,
-	}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	c.Transport.(*Transport).ResponseHeaderTimeout = 500 * time.Millisecond
 
 	tests := []struct {
 		path    string
@@ -1525,7 +1592,9 @@
 		{path: "/fast", want: 200},
 	}
 	for i, tt := range tests {
-		res, err := c.Get(ts.URL + tt.path)
+		req, _ := NewRequest("GET", ts.URL+tt.path, nil)
+		req = req.WithT(t)
+		res, err := c.Do(req)
 		select {
 		case <-inHandler:
 		case <-time.After(5 * time.Second):
@@ -1578,9 +1647,8 @@
 	defer ts.Close()
 	defer close(unblockc)
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	req, _ := NewRequest("GET", ts.URL, nil)
 	res, err := c.Do(req)
@@ -1688,9 +1756,8 @@
 	defer ts.Close()
 	defer close(unblockc)
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	req, _ := NewRequest("GET", ts.URL, nil)
 	ch := make(chan struct{})
@@ -1747,9 +1814,7 @@
 	defer ts.Close()
 	defer close(unblockc)
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
 
 	req, _ := NewRequest("GET", ts.URL, nil)
 	if withCtx {
@@ -1837,9 +1902,8 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	req, _ := NewRequest("GET", ts.URL, nil)
 	defer tr.CancelRequest(req)
@@ -1959,18 +2023,12 @@
 	defer ts.Close()
 
 	dialGate := make(chan bool, 1)
-	tr := &Transport{
-		Dial: func(n, addr string) (net.Conn, error) {
-			if <-dialGate {
-				return net.Dial(n, addr)
-			}
-			return nil, errors.New("manually closed")
-		},
-		DisableKeepAlives: false,
-	}
-	defer tr.CloseIdleConnections()
-	c := &Client{
-		Transport: tr,
+	c := ts.Client()
+	c.Transport.(*Transport).Dial = func(n, addr string) (net.Conn, error) {
+		if <-dialGate {
+			return net.Dial(n, addr)
+		}
+		return nil, errors.New("manually closed")
 	}
 
 	dialGate <- true // only allow one dial
@@ -2160,6 +2218,7 @@
 	{env: "https://cache.corp.example.com", want: "https://cache.corp.example.com"},
 	{env: "http://127.0.0.1:8080", want: "http://127.0.0.1:8080"},
 	{env: "https://127.0.0.1:8080", want: "https://127.0.0.1:8080"},
+	{env: "socks5://127.0.0.1", want: "socks5://127.0.0.1"},
 
 	// Don't use secure for http
 	{req: "http://insecure.tld/", env: "http.proxy.tld", httpsenv: "secure.proxy.tld", want: "http://http.proxy.tld"},
@@ -2184,6 +2243,7 @@
 
 func TestProxyFromEnvironment(t *testing.T) {
 	ResetProxyEnv()
+	defer ResetProxyEnv()
 	for _, tt := range proxyFromEnvTests {
 		os.Setenv("HTTP_PROXY", tt.env)
 		os.Setenv("HTTPS_PROXY", tt.httpsenv)
@@ -2223,14 +2283,11 @@
 	SetReadLoopBeforeNextReadHook(func() { didRead <- true })
 	defer SetReadLoopBeforeNextReadHook(nil)
 
-	tr := &Transport{
-		Dial: func(netw, addr string) (net.Conn, error) {
-			return net.Dial(netw, ts.Listener.Addr().String())
-		},
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
+	tr.Dial = func(netw, addr string) (net.Conn, error) {
+		return net.Dial(netw, ts.Listener.Addr().String())
 	}
-	defer tr.CloseIdleConnections()
-
-	c := &Client{Transport: tr}
 
 	// First, without keep-alives.
 	for _, disableKeep := range []bool{true, false} {
@@ -2273,13 +2330,11 @@
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	cl := &Client{Transport: tr}
+	c := ts.Client()
 
 	closes := 0
 
-	res, err := cl.Post(ts.URL, "text/plain", countCloseReader{&closes, strings.NewReader("hello")})
+	res, err := c.Post(ts.URL, "text/plain", countCloseReader{&closes, strings.NewReader("hello")})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -2365,20 +2420,16 @@
 		fmt.Fprintf(w, "hello")
 	}))
 	defer ts.Close()
-	tr := &Transport{
-		TLSClientConfig: &tls.Config{
-			InsecureSkipVerify: true,
-		},
-	}
-	defer tr.CloseIdleConnections()
-	client := &Client{Transport: tr}
+
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
 
 	var nSuccess = 0
 	var errs []error
 	const trials = 20
 	for i := 0; i < trials; i++ {
 		tr.CloseIdleConnections()
-		res, err := client.Get(ts.URL + "/keep-alive-then-die")
+		res, err := c.Get(ts.URL + "/keep-alive-then-die")
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -2393,7 +2444,7 @@
 
 		// Now try again and see if we successfully
 		// pick a new connection.
-		res, err = client.Get(ts.URL + "/")
+		res, err = c.Get(ts.URL + "/")
 		if err != nil {
 			errs = append(errs, err)
 			continue
@@ -2472,22 +2523,20 @@
 		go io.Copy(ioutil.Discard, conn)
 	}))
 	defer ts.Close()
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	client := &Client{Transport: tr}
+	c := ts.Client()
 
 	const bodySize = 256 << 10
 	finalBit := make(byteFromChanReader, 1)
 	req, _ := NewRequest("POST", ts.URL, io.MultiReader(io.LimitReader(neverEnding('x'), bodySize-1), finalBit))
 	req.ContentLength = bodySize
-	res, err := client.Do(req)
+	res, err := c.Do(req)
 	if err := wantBody(res, err, "foo"); err != nil {
 		t.Errorf("POST response: %v", err)
 	}
 	donec := make(chan bool)
 	go func() {
 		defer close(donec)
-		res, err = client.Get(ts.URL)
+		res, err = c.Get(ts.URL)
 		if err := wantBody(res, err, "bar"); err != nil {
 			t.Errorf("GET response: %v", err)
 			return
@@ -2519,10 +2568,9 @@
 		conn.Close()
 	}))
 	defer ts.Close()
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	cl := &Client{Transport: tr}
-	res, err := cl.Get(ts.URL)
+	c := ts.Client()
+
+	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatalf("Get: %v", err)
 	}
@@ -2553,89 +2601,160 @@
 
 func (c writerFuncConn) Write(p []byte) (n int, err error) { return c.write(p) }
 
-// Issue 4677. If we try to reuse a connection that the server is in the
-// process of closing, we may end up successfully writing out our request (or a
-// portion of our request) only to find a connection error when we try to read
-// from (or finish writing to) the socket.
+// Issues 4677, 18241, and 17844. If we try to reuse a connection that the
+// server is in the process of closing, we may end up successfully writing out
+// our request (or a portion of our request) only to find a connection error
+// when we try to read from (or finish writing to) the socket.
 //
-// NOTE: we resend a request only if the request is idempotent, we reused a
-// keep-alive connection, and we haven't yet received any header data. This
-// automatically prevents an infinite resend loop because we'll run out of the
-// cached keep-alive connections eventually.
-func TestRetryIdempotentRequestsOnError(t *testing.T) {
-	defer afterTest(t)
-
-	var (
-		mu     sync.Mutex
-		logbuf bytes.Buffer
-	)
-	logf := func(format string, args ...interface{}) {
-		mu.Lock()
-		defer mu.Unlock()
-		fmt.Fprintf(&logbuf, format, args...)
-		logbuf.WriteByte('\n')
+// NOTE: we resend a request only if:
+//   - we reused a keep-alive connection
+//   - we haven't yet received any header data
+//   - either we wrote no bytes to the server, or the request is idempotent
+// This automatically prevents an infinite resend loop because we'll run out of
+// the cached keep-alive connections eventually.
+func TestRetryRequestsOnError(t *testing.T) {
+	newRequest := func(method, urlStr string, body io.Reader) *Request {
+		req, err := NewRequest(method, urlStr, body)
+		if err != nil {
+			t.Fatal(err)
+		}
+		return req
 	}
 
-	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
-		logf("Handler")
-		w.Header().Set("X-Status", "ok")
-	}))
-	defer ts.Close()
-
-	var writeNumAtomic int32
-	tr := &Transport{
-		Dial: func(network, addr string) (net.Conn, error) {
-			logf("Dial")
-			c, err := net.Dial(network, ts.Listener.Addr().String())
-			if err != nil {
-				logf("Dial error: %v", err)
-				return nil, err
-			}
-			return &writerFuncConn{
-				Conn: c,
-				write: func(p []byte) (n int, err error) {
-					if atomic.AddInt32(&writeNumAtomic, 1) == 2 {
-						logf("intentional write failure")
-						return 0, errors.New("second write fails")
-					}
-					logf("Write(%q)", p)
-					return c.Write(p)
-				},
-			}, nil
+	testCases := []struct {
+		name       string
+		failureN   int
+		failureErr error
+		// Note that we can't just re-use the Request object across calls to c.Do
+		// because we need to rewind Body between calls.  (GetBody is only used to
+		// rewind Body on failure and redirects, not just because it's done.)
+		req       func() *Request
+		reqString string
+	}{
+		{
+			name: "IdempotentNoBodySomeWritten",
+			// Believe that we've written some bytes to the server, so we know we're
+			// not just in the "retry when no bytes sent" case".
+			failureN: 1,
+			// Use the specific error that shouldRetryRequest looks for with idempotent requests.
+			failureErr: ExportErrServerClosedIdle,
+			req: func() *Request {
+				return newRequest("GET", "http://fake.golang", nil)
+			},
+			reqString: `GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n`,
+		},
+		{
+			name: "IdempotentGetBodySomeWritten",
+			// Believe that we've written some bytes to the server, so we know we're
+			// not just in the "retry when no bytes sent" case".
+			failureN: 1,
+			// Use the specific error that shouldRetryRequest looks for with idempotent requests.
+			failureErr: ExportErrServerClosedIdle,
+			req: func() *Request {
+				return newRequest("GET", "http://fake.golang", strings.NewReader("foo\n"))
+			},
+			reqString: `GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nContent-Length: 4\r\nAccept-Encoding: gzip\r\n\r\nfoo\n`,
+		},
+		{
+			name: "NothingWrittenNoBody",
+			// It's key that we return 0 here -- that's what enables Transport to know
+			// that nothing was written, even though this is a non-idempotent request.
+			failureN:   0,
+			failureErr: errors.New("second write fails"),
+			req: func() *Request {
+				return newRequest("DELETE", "http://fake.golang", nil)
+			},
+			reqString: `DELETE / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n`,
+		},
+		{
+			name: "NothingWrittenGetBody",
+			// It's key that we return 0 here -- that's what enables Transport to know
+			// that nothing was written, even though this is a non-idempotent request.
+			failureN:   0,
+			failureErr: errors.New("second write fails"),
+			// Note that NewRequest will set up GetBody for strings.Reader, which is
+			// required for the retry to occur
+			req: func() *Request {
+				return newRequest("POST", "http://fake.golang", strings.NewReader("foo\n"))
+			},
+			reqString: `POST / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nContent-Length: 4\r\nAccept-Encoding: gzip\r\n\r\nfoo\n`,
 		},
 	}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
 
-	SetRoundTripRetried(func() {
-		logf("Retried.")
-	})
-	defer SetRoundTripRetried(nil)
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			defer afterTest(t)
 
-	for i := 0; i < 3; i++ {
-		res, err := c.Get("http://fake.golang/")
-		if err != nil {
-			t.Fatalf("i=%d: Get = %v", i, err)
-		}
-		res.Body.Close()
-	}
+			var (
+				mu     sync.Mutex
+				logbuf bytes.Buffer
+			)
+			logf := func(format string, args ...interface{}) {
+				mu.Lock()
+				defer mu.Unlock()
+				fmt.Fprintf(&logbuf, format, args...)
+				logbuf.WriteByte('\n')
+			}
 
-	mu.Lock()
-	got := logbuf.String()
-	mu.Unlock()
-	const want = `Dial
-Write("GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n")
+			ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+				logf("Handler")
+				w.Header().Set("X-Status", "ok")
+			}))
+			defer ts.Close()
+
+			var writeNumAtomic int32
+			c := ts.Client()
+			c.Transport.(*Transport).Dial = func(network, addr string) (net.Conn, error) {
+				logf("Dial")
+				c, err := net.Dial(network, ts.Listener.Addr().String())
+				if err != nil {
+					logf("Dial error: %v", err)
+					return nil, err
+				}
+				return &writerFuncConn{
+					Conn: c,
+					write: func(p []byte) (n int, err error) {
+						if atomic.AddInt32(&writeNumAtomic, 1) == 2 {
+							logf("intentional write failure")
+							return tc.failureN, tc.failureErr
+						}
+						logf("Write(%q)", p)
+						return c.Write(p)
+					},
+				}, nil
+			}
+
+			SetRoundTripRetried(func() {
+				logf("Retried.")
+			})
+			defer SetRoundTripRetried(nil)
+
+			for i := 0; i < 3; i++ {
+				res, err := c.Do(tc.req())
+				if err != nil {
+					t.Fatalf("i=%d: Do = %v", i, err)
+				}
+				res.Body.Close()
+			}
+
+			mu.Lock()
+			got := logbuf.String()
+			mu.Unlock()
+			want := fmt.Sprintf(`Dial
+Write("%s")
 Handler
 intentional write failure
 Retried.
 Dial
-Write("GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n")
+Write("%s")
 Handler
-Write("GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n")
+Write("%s")
 Handler
-`
-	if got != want {
-		t.Errorf("Log of events differs. Got:\n%s\nWant:\n%s", got, want)
+`, tc.reqString, tc.reqString, tc.reqString)
+			if got != want {
+				t.Errorf("Log of events differs. Got:\n%s\nWant:\n%s", got, want)
+			}
+		})
 	}
 }
 
@@ -2649,6 +2768,7 @@
 		readBody <- err
 	}))
 	defer ts.Close()
+	c := ts.Client()
 	fakeErr := errors.New("fake error")
 	didClose := make(chan bool, 1)
 	req, _ := NewRequest("POST", ts.URL, struct {
@@ -2664,7 +2784,7 @@
 			return nil
 		}),
 	})
-	res, err := DefaultClient.Do(req)
+	res, err := c.Do(req)
 	if res != nil {
 		defer res.Body.Close()
 	}
@@ -2698,23 +2818,19 @@
 		mu.Unlock()
 	}))
 	defer ts.Close()
-	tr := &Transport{
-		DialTLS: func(netw, addr string) (net.Conn, error) {
-			mu.Lock()
-			didDial = true
-			mu.Unlock()
-			c, err := tls.Dial(netw, addr, &tls.Config{
-				InsecureSkipVerify: true,
-			})
-			if err != nil {
-				return nil, err
-			}
-			return c, c.Handshake()
-		},
+	c := ts.Client()
+	c.Transport.(*Transport).DialTLS = func(netw, addr string) (net.Conn, error) {
+		mu.Lock()
+		didDial = true
+		mu.Unlock()
+		c, err := tls.Dial(netw, addr, c.Transport.(*Transport).TLSClientConfig)
+		if err != nil {
+			return nil, err
+		}
+		return c, c.Handshake()
 	}
-	defer tr.CloseIdleConnections()
-	client := &Client{Transport: tr}
-	res, err := client.Get(ts.URL)
+
+	res, err := c.Get(ts.URL)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -2796,10 +2912,11 @@
 		reqc <- r
 	}))
 	defer ts.Close()
+	c := ts.Client()
 
 	req, _ := NewRequest("GET", ts.URL, nil)
 	req.Header.Set("Range", "bytes=7-11")
-	res, err := DefaultClient.Do(req)
+	res, err := c.Do(req)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -2828,9 +2945,7 @@
 		w.Write(b[:])
 	}))
 	defer ts.Close()
-
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
+	tr := ts.Client().Transport.(*Transport)
 
 	req, err := NewRequest("GET", ts.URL, nil)
 	if err != nil {
@@ -2859,14 +2974,46 @@
 	res.Body.Close()
 }
 
+// Test for issue 19248: Content-Encoding's value is case insensitive.
+func TestTransportContentEncodingCaseInsensitive(t *testing.T) {
+	setParallel(t)
+	defer afterTest(t)
+	for _, ce := range []string{"gzip", "GZIP"} {
+		ce := ce
+		t.Run(ce, func(t *testing.T) {
+			const encodedString = "Hello Gopher"
+			ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+				w.Header().Set("Content-Encoding", ce)
+				gz := gzip.NewWriter(w)
+				gz.Write([]byte(encodedString))
+				gz.Close()
+			}))
+			defer ts.Close()
+
+			res, err := ts.Client().Get(ts.URL)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			body, err := ioutil.ReadAll(res.Body)
+			res.Body.Close()
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if string(body) != encodedString {
+				t.Fatalf("Expected body %q, got: %q\n", encodedString, string(body))
+			}
+		})
+	}
+}
+
 func TestTransportDialCancelRace(t *testing.T) {
 	defer afterTest(t)
 
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {}))
 	defer ts.Close()
-
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
+	tr := ts.Client().Transport.(*Transport)
 
 	req, err := NewRequest("GET", ts.URL, nil)
 	if err != nil {
@@ -2993,6 +3140,7 @@
 		w.WriteHeader(StatusOK)
 	}))
 	defer ts.Close()
+	c := ts.Client()
 
 	fail := 0
 	count := 100
@@ -3002,10 +3150,7 @@
 		if err != nil {
 			t.Fatal(err)
 		}
-		tr := new(Transport)
-		defer tr.CloseIdleConnections()
-		client := &Client{Transport: tr}
-		resp, err := client.Do(req)
+		resp, err := c.Do(req)
 		if err != nil {
 			fail++
 			t.Logf("%d = %#v", i, err)
@@ -3218,10 +3363,8 @@
 		w.Write(rgz) // arbitrary gzip response
 	}))
 	defer ts.Close()
+	c := ts.Client()
 
-	tr := &Transport{}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
 	for i := 0; i < 2; i++ {
 		res, err := c.Get(ts.URL)
 		if err != nil {
@@ -3250,12 +3393,9 @@
 		}
 	}))
 	defer ts.Close()
+	c := ts.Client()
+	c.Transport.(*Transport).MaxResponseHeaderBytes = 512 << 10
 
-	tr := &Transport{
-		MaxResponseHeaderBytes: 512 << 10,
-	}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
 	if res, err := c.Get(ts.URL); err != nil {
 		t.Fatal(err)
 	} else {
@@ -3426,16 +3566,26 @@
 	}
 }
 
-func TestTransportEventTraceRealDNS(t *testing.T) {
-	if testing.Short() && testenv.Builder() == "" {
-		// Skip this test in short mode (the default for
-		// all.bash), in case the user is using a shady/ISP
-		// DNS server hijacking queries.
-		// See issues 16732, 16716.
-		// Our builders use 8.8.8.8, though, which correctly
-		// returns NXDOMAIN, so still run this test there.
-		t.Skip("skipping in short mode")
+var (
+	isDNSHijackedOnce sync.Once
+	isDNSHijacked     bool
+)
+
+func skipIfDNSHijacked(t *testing.T) {
+	// Skip this test if the user is using a shady/ISP
+	// DNS server hijacking queries.
+	// See issues 16732, 16716.
+	isDNSHijackedOnce.Do(func() {
+		addrs, _ := net.LookupHost("dns-should-not-resolve.golang")
+		isDNSHijacked = len(addrs) != 0
+	})
+	if isDNSHijacked {
+		t.Skip("skipping; test requires non-hijacking DNS server")
 	}
+}
+
+func TestTransportEventTraceRealDNS(t *testing.T) {
+	skipIfDNSHijacked(t)
 	defer afterTest(t)
 	tr := &Transport{}
 	defer tr.CloseIdleConnections()
@@ -3506,8 +3656,8 @@
 // connections. The http2 test is done in TestTransportEventTrace_h2
 func TestTLSHandshakeTrace(t *testing.T) {
 	defer afterTest(t)
-	s := httptest.NewTLSServer(HandlerFunc(func(w ResponseWriter, r *Request) {}))
-	defer s.Close()
+	ts := httptest.NewTLSServer(HandlerFunc(func(w ResponseWriter, r *Request) {}))
+	defer ts.Close()
 
 	var mu sync.Mutex
 	var start, done bool
@@ -3527,10 +3677,8 @@
 		},
 	}
 
-	tr := &Transport{TLSClientConfig: &tls.Config{InsecureSkipVerify: true}}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
-	req, err := NewRequest("GET", s.URL, nil)
+	c := ts.Client()
+	req, err := NewRequest("GET", ts.URL, nil)
 	if err != nil {
 		t.Fatal("Unable to construct test request:", err)
 	}
@@ -3557,16 +3705,14 @@
 		// No body for convenience.
 	}))
 	defer ts.Close()
-	tr := &Transport{
-		MaxIdleConns: 4,
-	}
-	defer tr.CloseIdleConnections()
+	c := ts.Client()
+	tr := c.Transport.(*Transport)
+	tr.MaxIdleConns = 4
 
 	ip, port, err := net.SplitHostPort(ts.Listener.Addr().String())
 	if err != nil {
 		t.Fatal(err)
 	}
-	c := &Client{Transport: tr}
 	ctx := context.WithValue(context.Background(), nettrace.LookupIPAltResolverKey{}, func(ctx context.Context, host string) ([]net.IPAddr, error) {
 		return []net.IPAddr{{IP: net.ParseIP(ip)}}, nil
 	})
@@ -3862,17 +4008,16 @@
 		c.Close()
 	}))
 	defer ts.Close()
-	tr := &Transport{
-		ProxyConnectHeader: Header{
-			"User-Agent": {"foo"},
-			"Other":      {"bar"},
-		},
-		Proxy: func(r *Request) (*url.URL, error) {
-			return url.Parse(ts.URL)
-		},
+
+	c := ts.Client()
+	c.Transport.(*Transport).Proxy = func(r *Request) (*url.URL, error) {
+		return url.Parse(ts.URL)
 	}
-	defer tr.CloseIdleConnections()
-	c := &Client{Transport: tr}
+	c.Transport.(*Transport).ProxyConnectHeader = Header{
+		"User-Agent": {"foo"},
+		"Other":      {"bar"},
+	}
+
 	res, err := c.Get("https://dummy.tld/") // https to force a CONNECT
 	if err == nil {
 		res.Body.Close()
diff --git a/libgo/go/net/interface.go b/libgo/go/net/interface.go
index b3297f2..4036a7f 100644
--- a/libgo/go/net/interface.go
+++ b/libgo/go/net/interface.go
@@ -211,30 +211,30 @@
 	}
 }
 
-func zoneToString(zone int) string {
-	if zone == 0 {
+func (zc *ipv6ZoneCache) name(index int) string {
+	if index == 0 {
 		return ""
 	}
 	zoneCache.update(nil)
 	zoneCache.RLock()
 	defer zoneCache.RUnlock()
-	name, ok := zoneCache.toName[zone]
+	name, ok := zoneCache.toName[index]
 	if !ok {
-		name = uitoa(uint(zone))
+		name = uitoa(uint(index))
 	}
 	return name
 }
 
-func zoneToInt(zone string) int {
-	if zone == "" {
+func (zc *ipv6ZoneCache) index(name string) int {
+	if name == "" {
 		return 0
 	}
 	zoneCache.update(nil)
 	zoneCache.RLock()
 	defer zoneCache.RUnlock()
-	index, ok := zoneCache.toIndex[zone]
+	index, ok := zoneCache.toIndex[name]
 	if !ok {
-		index, _, _ = dtoi(zone)
+		index, _, _ = dtoi(name)
 	}
 	return index
 }
diff --git a/libgo/go/net/interface_linux.go b/libgo/go/net/interface_linux.go
index 5e391b2..441ab2f 100644
--- a/libgo/go/net/interface_linux.go
+++ b/libgo/go/net/interface_linux.go
@@ -162,7 +162,7 @@
 				if err != nil {
 					return nil, os.NewSyscallError("parsenetlinkrouteattr", err)
 				}
-				ifa := newAddr(ifi, ifam, attrs)
+				ifa := newAddr(ifam, attrs)
 				if ifa != nil {
 					ifat = append(ifat, ifa)
 				}
@@ -172,7 +172,7 @@
 	return ifat, nil
 }
 
-func newAddr(ifi *Interface, ifam *syscall.IfAddrmsg, attrs []syscall.NetlinkRouteAttr) Addr {
+func newAddr(ifam *syscall.IfAddrmsg, attrs []syscall.NetlinkRouteAttr) Addr {
 	var ipPointToPoint bool
 	// Seems like we need to make sure whether the IP interface
 	// stack consists of IP point-to-point numbered or unnumbered
diff --git a/libgo/go/net/interface_test.go b/libgo/go/net/interface_test.go
index 38a2ca4..534137a 100644
--- a/libgo/go/net/interface_test.go
+++ b/libgo/go/net/interface_test.go
@@ -262,13 +262,13 @@
 
 func checkUnicastStats(ifStats *ifStats, uniStats *routeStats) error {
 	// Test the existence of connected unicast routes for IPv4.
-	if supportsIPv4 && ifStats.loop+ifStats.other > 0 && uniStats.ipv4 == 0 {
+	if supportsIPv4() && ifStats.loop+ifStats.other > 0 && uniStats.ipv4 == 0 {
 		return fmt.Errorf("num IPv4 unicast routes = 0; want >0; summary: %+v, %+v", ifStats, uniStats)
 	}
 	// Test the existence of connected unicast routes for IPv6.
 	// We can assume the existence of ::1/128 when at least one
 	// loopback interface is installed.
-	if supportsIPv6 && ifStats.loop > 0 && uniStats.ipv6 == 0 {
+	if supportsIPv6() && ifStats.loop > 0 && uniStats.ipv6 == 0 {
 		return fmt.Errorf("num IPv6 unicast routes = 0; want >0; summary: %+v, %+v", ifStats, uniStats)
 	}
 	return nil
@@ -290,7 +290,7 @@
 		// We can assume the existence of connected multicast
 		// route clones when at least two connected unicast
 		// routes, ::1/128 and other, are installed.
-		if supportsIPv6 && ifStats.loop > 0 && uniStats.ipv6 > 1 && multiStats.ipv6 == 0 {
+		if supportsIPv6() && ifStats.loop > 0 && uniStats.ipv6 > 1 && multiStats.ipv6 == 0 {
 			return fmt.Errorf("num IPv6 multicast route clones = 0; want >0; summary: %+v, %+v, %+v", ifStats, uniStats, multiStats)
 		}
 	}
diff --git a/libgo/go/net/interface_windows.go b/libgo/go/net/interface_windows.go
index 8b976e5..b08d158 100644
--- a/libgo/go/net/interface_windows.go
+++ b/libgo/go/net/interface_windows.go
@@ -24,10 +24,7 @@
 	if err != nil {
 		return true // Windows 10 and above will deprecate this API
 	}
-	if byte(v) < 6 { // major version of Windows Vista is 6
-		return false
-	}
-	return true
+	return byte(v) >= 6 // major version of Windows Vista is 6
 }
 
 // adapterAddresses returns a list of IP adapter and address
diff --git a/libgo/go/net/internal/socktest/sys_cloexec.go b/libgo/go/net/internal/socktest/sys_cloexec.go
index 340ff07..d1b8f4f 100644
--- a/libgo/go/net/internal/socktest/sys_cloexec.go
+++ b/libgo/go/net/internal/socktest/sys_cloexec.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build freebsd linux
+// +build dragonfly freebsd linux
 
 package socktest
 
@@ -15,7 +15,7 @@
 		return syscall.Accept4(s, flags)
 	}
 	sw.fmu.RLock()
-	f, _ := sw.fltab[FilterAccept]
+	f := sw.fltab[FilterAccept]
 	sw.fmu.RUnlock()
 
 	af, err := f.apply(so)
diff --git a/libgo/go/net/internal/socktest/sys_unix.go b/libgo/go/net/internal/socktest/sys_unix.go
index a3d1282..397c524 100644
--- a/libgo/go/net/internal/socktest/sys_unix.go
+++ b/libgo/go/net/internal/socktest/sys_unix.go
@@ -14,7 +14,7 @@
 
 	so := &Status{Cookie: cookie(family, sotype, proto)}
 	sw.fmu.RLock()
-	f, _ := sw.fltab[FilterSocket]
+	f := sw.fltab[FilterSocket]
 	sw.fmu.RUnlock()
 
 	af, err := f.apply(so)
@@ -47,7 +47,7 @@
 		return syscall.Close(s)
 	}
 	sw.fmu.RLock()
-	f, _ := sw.fltab[FilterClose]
+	f := sw.fltab[FilterClose]
 	sw.fmu.RUnlock()
 
 	af, err := f.apply(so)
@@ -77,7 +77,7 @@
 		return syscall.Connect(s, sa)
 	}
 	sw.fmu.RLock()
-	f, _ := sw.fltab[FilterConnect]
+	f := sw.fltab[FilterConnect]
 	sw.fmu.RUnlock()
 
 	af, err := f.apply(so)
@@ -106,7 +106,7 @@
 		return syscall.Listen(s, backlog)
 	}
 	sw.fmu.RLock()
-	f, _ := sw.fltab[FilterListen]
+	f := sw.fltab[FilterListen]
 	sw.fmu.RUnlock()
 
 	af, err := f.apply(so)
@@ -135,7 +135,7 @@
 		return syscall.Accept(s)
 	}
 	sw.fmu.RLock()
-	f, _ := sw.fltab[FilterAccept]
+	f := sw.fltab[FilterAccept]
 	sw.fmu.RUnlock()
 
 	af, err := f.apply(so)
@@ -168,7 +168,7 @@
 		return syscall.GetsockoptInt(s, level, opt)
 	}
 	sw.fmu.RLock()
-	f, _ := sw.fltab[FilterGetsockoptInt]
+	f := sw.fltab[FilterGetsockoptInt]
 	sw.fmu.RUnlock()
 
 	af, err := f.apply(so)
diff --git a/libgo/go/net/ip.go b/libgo/go/net/ip.go
index db3364c..6b7ba4c 100644
--- a/libgo/go/net/ip.go
+++ b/libgo/go/net/ip.go
@@ -12,6 +12,8 @@
 
 package net
 
+import _ "unsafe" // for go:linkname
+
 // IP address lengths (bytes).
 const (
 	IPv4len = 4
@@ -106,7 +108,8 @@
 	IPv6linklocalallrouters    = IP{0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x02}
 )
 
-// IsUnspecified reports whether ip is an unspecified address.
+// IsUnspecified reports whether ip is an unspecified address, either
+// the IPv4 address "0.0.0.0" or the IPv6 address "::".
 func (ip IP) IsUnspecified() bool {
 	return ip.Equal(IPv4zero) || ip.Equal(IPv6unspecified)
 }
@@ -338,7 +341,8 @@
 }
 
 // MarshalText implements the encoding.TextMarshaler interface.
-// The encoding is the same as returned by String.
+// The encoding is the same as returned by String, with one exception:
+// When len(ip) is zero, it returns an empty slice.
 func (ip IP) MarshalText() ([]byte, error) {
 	if len(ip) == 0 {
 		return []byte(""), nil
@@ -381,17 +385,9 @@
 	return false
 }
 
-func bytesEqual(x, y []byte) bool {
-	if len(x) != len(y) {
-		return false
-	}
-	for i, b := range x {
-		if y[i] != b {
-			return false
-		}
-	}
-	return true
-}
+// bytes.Equal is implemented in runtime/asm_$goarch.s
+//go:linkname bytesEqual bytes.Equal
+func bytesEqual(x, y []byte) bool
 
 func (ip IP) matchAddrFamily(x IP) bool {
 	return ip.To4() != nil && x.To4() != nil || ip.To16() != nil && ip.To4() == nil && x.To16() != nil && x.To4() == nil
@@ -667,7 +663,7 @@
 // It returns the IP address and the network implied by the IP and
 // prefix length.
 // For example, ParseCIDR("192.0.2.1/24") returns the IP address
-// 198.0.2.1 and the network 198.0.2.0/24.
+// 192.0.2.1 and the network 192.0.2.0/24.
 func ParseCIDR(s string) (IP, *IPNet, error) {
 	i := byteIndex(s, '/')
 	if i < 0 {
diff --git a/libgo/go/net/ip_test.go b/libgo/go/net/ip_test.go
index 4655163..ad13388 100644
--- a/libgo/go/net/ip_test.go
+++ b/libgo/go/net/ip_test.go
@@ -6,6 +6,7 @@
 
 import (
 	"bytes"
+	"math/rand"
 	"reflect"
 	"runtime"
 	"testing"
@@ -468,61 +469,77 @@
 	}
 }
 
-var splitJoinTests = []struct {
-	host string
-	port string
-	join string
-}{
-	{"www.google.com", "80", "www.google.com:80"},
-	{"127.0.0.1", "1234", "127.0.0.1:1234"},
-	{"::1", "80", "[::1]:80"},
-	{"fe80::1%lo0", "80", "[fe80::1%lo0]:80"},
-	{"localhost%lo0", "80", "[localhost%lo0]:80"},
-	{"", "0", ":0"},
-
-	{"google.com", "https%foo", "google.com:https%foo"}, // Go 1.0 behavior
-	{"127.0.0.1", "", "127.0.0.1:"},                     // Go 1.0 behavior
-	{"www.google.com", "", "www.google.com:"},           // Go 1.0 behavior
-}
-
-var splitFailureTests = []struct {
-	hostPort string
-	err      string
-}{
-	{"www.google.com", "missing port in address"},
-	{"127.0.0.1", "missing port in address"},
-	{"[::1]", "missing port in address"},
-	{"[fe80::1%lo0]", "missing port in address"},
-	{"[localhost%lo0]", "missing port in address"},
-	{"localhost%lo0", "missing port in address"},
-
-	{"::1", "too many colons in address"},
-	{"fe80::1%lo0", "too many colons in address"},
-	{"fe80::1%lo0:80", "too many colons in address"},
-
-	{"localhost%lo0:80", "missing brackets in address"},
-
-	// Test cases that didn't fail in Go 1.0
-
-	{"[foo:bar]", "missing port in address"},
-	{"[foo:bar]baz", "missing port in address"},
-	{"[foo]bar:baz", "missing port in address"},
-
-	{"[foo]:[bar]:baz", "too many colons in address"},
-
-	{"[foo]:[bar]baz", "unexpected '[' in address"},
-	{"foo[bar]:baz", "unexpected '[' in address"},
-
-	{"foo]bar:baz", "unexpected ']' in address"},
-}
-
 func TestSplitHostPort(t *testing.T) {
-	for _, tt := range splitJoinTests {
-		if host, port, err := SplitHostPort(tt.join); host != tt.host || port != tt.port || err != nil {
-			t.Errorf("SplitHostPort(%q) = %q, %q, %v; want %q, %q, nil", tt.join, host, port, err, tt.host, tt.port)
+	for _, tt := range []struct {
+		hostPort string
+		host     string
+		port     string
+	}{
+		// Host name
+		{"localhost:http", "localhost", "http"},
+		{"localhost:80", "localhost", "80"},
+
+		// Go-specific host name with zone identifier
+		{"localhost%lo0:http", "localhost%lo0", "http"},
+		{"localhost%lo0:80", "localhost%lo0", "80"},
+		{"[localhost%lo0]:http", "localhost%lo0", "http"}, // Go 1 behavior
+		{"[localhost%lo0]:80", "localhost%lo0", "80"},     // Go 1 behavior
+
+		// IP literal
+		{"127.0.0.1:http", "127.0.0.1", "http"},
+		{"127.0.0.1:80", "127.0.0.1", "80"},
+		{"[::1]:http", "::1", "http"},
+		{"[::1]:80", "::1", "80"},
+
+		// IP literal with zone identifier
+		{"[::1%lo0]:http", "::1%lo0", "http"},
+		{"[::1%lo0]:80", "::1%lo0", "80"},
+
+		// Go-specific wildcard for host name
+		{":http", "", "http"}, // Go 1 behavior
+		{":80", "", "80"},     // Go 1 behavior
+
+		// Go-specific wildcard for service name or transport port number
+		{"golang.org:", "golang.org", ""}, // Go 1 behavior
+		{"127.0.0.1:", "127.0.0.1", ""},   // Go 1 behavior
+		{"[::1]:", "::1", ""},             // Go 1 behavior
+
+		// Opaque service name
+		{"golang.org:https%foo", "golang.org", "https%foo"}, // Go 1 behavior
+	} {
+		if host, port, err := SplitHostPort(tt.hostPort); host != tt.host || port != tt.port || err != nil {
+			t.Errorf("SplitHostPort(%q) = %q, %q, %v; want %q, %q, nil", tt.hostPort, host, port, err, tt.host, tt.port)
 		}
 	}
-	for _, tt := range splitFailureTests {
+
+	for _, tt := range []struct {
+		hostPort string
+		err      string
+	}{
+		{"golang.org", "missing port in address"},
+		{"127.0.0.1", "missing port in address"},
+		{"[::1]", "missing port in address"},
+		{"[fe80::1%lo0]", "missing port in address"},
+		{"[localhost%lo0]", "missing port in address"},
+		{"localhost%lo0", "missing port in address"},
+
+		{"::1", "too many colons in address"},
+		{"fe80::1%lo0", "too many colons in address"},
+		{"fe80::1%lo0:80", "too many colons in address"},
+
+		// Test cases that didn't fail in Go 1
+
+		{"[foo:bar]", "missing port in address"},
+		{"[foo:bar]baz", "missing port in address"},
+		{"[foo]bar:baz", "missing port in address"},
+
+		{"[foo]:[bar]:baz", "too many colons in address"},
+
+		{"[foo]:[bar]baz", "unexpected '[' in address"},
+		{"foo[bar]:baz", "unexpected '[' in address"},
+
+		{"foo]bar:baz", "unexpected ']' in address"},
+	} {
 		if host, port, err := SplitHostPort(tt.hostPort); err == nil {
 			t.Errorf("SplitHostPort(%q) should have failed", tt.hostPort)
 		} else {
@@ -538,9 +555,43 @@
 }
 
 func TestJoinHostPort(t *testing.T) {
-	for _, tt := range splitJoinTests {
-		if join := JoinHostPort(tt.host, tt.port); join != tt.join {
-			t.Errorf("JoinHostPort(%q, %q) = %q; want %q", tt.host, tt.port, join, tt.join)
+	for _, tt := range []struct {
+		host     string
+		port     string
+		hostPort string
+	}{
+		// Host name
+		{"localhost", "http", "localhost:http"},
+		{"localhost", "80", "localhost:80"},
+
+		// Go-specific host name with zone identifier
+		{"localhost%lo0", "http", "localhost%lo0:http"},
+		{"localhost%lo0", "80", "localhost%lo0:80"},
+
+		// IP literal
+		{"127.0.0.1", "http", "127.0.0.1:http"},
+		{"127.0.0.1", "80", "127.0.0.1:80"},
+		{"::1", "http", "[::1]:http"},
+		{"::1", "80", "[::1]:80"},
+
+		// IP literal with zone identifier
+		{"::1%lo0", "http", "[::1%lo0]:http"},
+		{"::1%lo0", "80", "[::1%lo0]:80"},
+
+		// Go-specific wildcard for host name
+		{"", "http", ":http"}, // Go 1 behavior
+		{"", "80", ":80"},     // Go 1 behavior
+
+		// Go-specific wildcard for service name or transport port number
+		{"golang.org", "", "golang.org:"}, // Go 1 behavior
+		{"127.0.0.1", "", "127.0.0.1:"},   // Go 1 behavior
+		{"::1", "", "[::1]:"},             // Go 1 behavior
+
+		// Opaque service name
+		{"golang.org", "https%foo", "golang.org:https%foo"}, // Go 1 behavior
+	} {
+		if hostPort := JoinHostPort(tt.host, tt.port); hostPort != tt.hostPort {
+			t.Errorf("JoinHostPort(%q, %q) = %q; want %q", tt.host, tt.port, hostPort, tt.hostPort)
 		}
 	}
 }
@@ -645,3 +696,32 @@
 		}
 	}
 }
+
+func BenchmarkIPEqual(b *testing.B) {
+	b.Run("IPv4", func(b *testing.B) {
+		benchmarkIPEqual(b, IPv4len)
+	})
+	b.Run("IPv6", func(b *testing.B) {
+		benchmarkIPEqual(b, IPv6len)
+	})
+}
+
+func benchmarkIPEqual(b *testing.B, size int) {
+	ips := make([]IP, 1000)
+	for i := range ips {
+		ips[i] = make(IP, size)
+		rand.Read(ips[i])
+	}
+	// Half of the N are equal.
+	for i := 0; i < b.N/2; i++ {
+		x := ips[i%len(ips)]
+		y := ips[i%len(ips)]
+		x.Equal(y)
+	}
+	// The other half are not equal.
+	for i := 0; i < b.N/2; i++ {
+		x := ips[i%len(ips)]
+		y := ips[(i+1)%len(ips)]
+		x.Equal(y)
+	}
+}
diff --git a/libgo/go/net/iprawsock.go b/libgo/go/net/iprawsock.go
index d994fc6..c4b54f0 100644
--- a/libgo/go/net/iprawsock.go
+++ b/libgo/go/net/iprawsock.go
@@ -61,30 +61,37 @@
 	return a
 }
 
-// ResolveIPAddr parses addr as an IP address of the form "host" or
-// "ipv6-host%zone" and resolves the domain name on the network net,
-// which must be "ip", "ip4" or "ip6".
+// ResolveIPAddr returns an address of IP end point.
 //
-// Resolving a hostname is not recommended because this returns at most
-// one of its IP addresses.
-func ResolveIPAddr(net, addr string) (*IPAddr, error) {
-	if net == "" { // a hint wildcard for Go 1.0 undocumented behavior
-		net = "ip"
+// The network must be an IP network name.
+//
+// If the host in the address parameter is not a literal IP address,
+// ResolveIPAddr resolves the address to an address of IP end point.
+// Otherwise, it parses the address as a literal IP address.
+// The address parameter can use a host name, but this is not
+// recommended, because it will return at most one of the host name's
+// IP addresses.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func ResolveIPAddr(network, address string) (*IPAddr, error) {
+	if network == "" { // a hint wildcard for Go 1.0 undocumented behavior
+		network = "ip"
 	}
-	afnet, _, err := parseNetwork(context.Background(), net)
+	afnet, _, err := parseNetwork(context.Background(), network, false)
 	if err != nil {
 		return nil, err
 	}
 	switch afnet {
 	case "ip", "ip4", "ip6":
 	default:
-		return nil, UnknownNetworkError(net)
+		return nil, UnknownNetworkError(network)
 	}
-	addrs, err := DefaultResolver.internetAddrList(context.Background(), afnet, addr)
+	addrs, err := DefaultResolver.internetAddrList(context.Background(), afnet, address)
 	if err != nil {
 		return nil, err
 	}
-	return addrs.first(isIPv4).(*IPAddr), nil
+	return addrs.forResolve(network, address).(*IPAddr), nil
 }
 
 // IPConn is the implementation of the Conn and PacketConn interfaces
@@ -93,13 +100,16 @@
 	conn
 }
 
-// ReadFromIP reads an IP packet from c, copying the payload into b.
-// It returns the number of bytes copied into b and the return address
-// that was on the packet.
-//
-// ReadFromIP can be made to time out and return an error with
-// Timeout() == true after a fixed time limit; see SetDeadline and
-// SetReadDeadline.
+// SyscallConn returns a raw network connection.
+// This implements the syscall.Conn interface.
+func (c *IPConn) SyscallConn() (syscall.RawConn, error) {
+	if !c.ok() {
+		return nil, syscall.EINVAL
+	}
+	return newRawConn(c.fd)
+}
+
+// ReadFromIP acts like ReadFrom but returns an IPAddr.
 func (c *IPConn) ReadFromIP(b []byte) (int, *IPAddr, error) {
 	if !c.ok() {
 		return 0, nil, syscall.EINVAL
@@ -126,10 +136,13 @@
 	return n, addr, err
 }
 
-// ReadMsgIP reads a packet from c, copying the payload into b and the
-// associated out-of-band data into oob. It returns the number of
+// ReadMsgIP reads a message from c, copying the payload into b and
+// the associated out-of-band data into oob. It returns the number of
 // bytes copied into b, the number of bytes copied into oob, the flags
-// that were set on the packet and the source address of the packet.
+// that were set on the message and the source address of the message.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
 func (c *IPConn) ReadMsgIP(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) {
 	if !c.ok() {
 		return 0, 0, 0, nil, syscall.EINVAL
@@ -141,13 +154,7 @@
 	return
 }
 
-// WriteToIP writes an IP packet to addr via c, copying the payload
-// from b.
-//
-// WriteToIP can be made to time out and return an error with
-// Timeout() == true after a fixed time limit; see SetDeadline and
-// SetWriteDeadline. On packet-oriented connections, write timeouts
-// are rare.
+// WriteToIP acts like WriteTo but takes an IPAddr.
 func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (int, error) {
 	if !c.ok() {
 		return 0, syscall.EINVAL
@@ -175,9 +182,12 @@
 	return n, err
 }
 
-// WriteMsgIP writes a packet to addr via c, copying the payload from
+// WriteMsgIP writes a message to addr via c, copying the payload from
 // b and the associated out-of-band data from oob. It returns the
 // number of payload and out-of-band bytes written.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
 func (c *IPConn) WriteMsgIP(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
 	if !c.ok() {
 		return 0, 0, syscall.EINVAL
@@ -191,25 +201,32 @@
 
 func newIPConn(fd *netFD) *IPConn { return &IPConn{conn{fd}} }
 
-// DialIP connects to the remote address raddr on the network protocol
-// netProto, which must be "ip", "ip4", or "ip6" followed by a colon
-// and a protocol number or name.
-func DialIP(netProto string, laddr, raddr *IPAddr) (*IPConn, error) {
-	c, err := dialIP(context.Background(), netProto, laddr, raddr)
+// DialIP acts like Dial for IP networks.
+//
+// The network must be an IP network name; see func Dial for details.
+//
+// If laddr is nil, a local address is automatically chosen.
+// If the IP field of raddr is nil or an unspecified IP address, the
+// local system is assumed.
+func DialIP(network string, laddr, raddr *IPAddr) (*IPConn, error) {
+	c, err := dialIP(context.Background(), network, laddr, raddr)
 	if err != nil {
-		return nil, &OpError{Op: "dial", Net: netProto, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
 	}
 	return c, nil
 }
 
-// ListenIP listens for incoming IP packets addressed to the local
-// address laddr. The returned connection's ReadFrom and WriteTo
-// methods can be used to receive and send IP packets with per-packet
-// addressing.
-func ListenIP(netProto string, laddr *IPAddr) (*IPConn, error) {
-	c, err := listenIP(context.Background(), netProto, laddr)
+// ListenIP acts like ListenPacket for IP networks.
+//
+// The network must be an IP network name; see func Dial for details.
+//
+// If the IP field of laddr is nil or an unspecified IP address,
+// ListenIP listens on all available IP addresses of the local system
+// except multicast IP addresses.
+func ListenIP(network string, laddr *IPAddr) (*IPConn, error) {
+	c, err := listenIP(context.Background(), network, laddr)
 	if err != nil {
-		return nil, &OpError{Op: "listen", Net: netProto, Source: nil, Addr: laddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
 	}
 	return c, nil
 }
diff --git a/libgo/go/net/iprawsock_posix.go b/libgo/go/net/iprawsock_posix.go
index 16e65dc..d613e6f 100644
--- a/libgo/go/net/iprawsock_posix.go
+++ b/libgo/go/net/iprawsock_posix.go
@@ -16,7 +16,7 @@
 	case *syscall.SockaddrInet4:
 		return &IPAddr{IP: sa.Addr[0:]}
 	case *syscall.SockaddrInet6:
-		return &IPAddr{IP: sa.Addr[0:], Zone: zoneToString(int(sa.ZoneId))}
+		return &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
 	}
 	return nil
 }
@@ -52,7 +52,7 @@
 		addr = &IPAddr{IP: sa.Addr[0:]}
 		n = stripIPv4Header(n, b)
 	case *syscall.SockaddrInet6:
-		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneToString(int(sa.ZoneId))}
+		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
 	}
 	return n, addr, err
 }
@@ -79,7 +79,7 @@
 	case *syscall.SockaddrInet4:
 		addr = &IPAddr{IP: sa.Addr[0:]}
 	case *syscall.SockaddrInet6:
-		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneToString(int(sa.ZoneId))}
+		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
 	}
 	return
 }
@@ -113,7 +113,7 @@
 }
 
 func dialIP(ctx context.Context, netProto string, laddr, raddr *IPAddr) (*IPConn, error) {
-	network, proto, err := parseNetwork(ctx, netProto)
+	network, proto, err := parseNetwork(ctx, netProto, true)
 	if err != nil {
 		return nil, err
 	}
@@ -133,7 +133,7 @@
 }
 
 func listenIP(ctx context.Context, netProto string, laddr *IPAddr) (*IPConn, error) {
-	network, proto, err := parseNetwork(ctx, netProto)
+	network, proto, err := parseNetwork(ctx, netProto, true)
 	if err != nil {
 		return nil, err
 	}
diff --git a/libgo/go/net/iprawsock_test.go b/libgo/go/net/iprawsock_test.go
index 5d33b26..8972051 100644
--- a/libgo/go/net/iprawsock_test.go
+++ b/libgo/go/net/iprawsock_test.go
@@ -117,3 +117,75 @@
 		t.Fatalf("got %#v; want %#v", c.RemoteAddr(), raddr)
 	}
 }
+
+func TestDialListenIPArgs(t *testing.T) {
+	type test struct {
+		argLists   [][2]string
+		shouldFail bool
+	}
+	tests := []test{
+		{
+			argLists: [][2]string{
+				{"ip", "127.0.0.1"},
+				{"ip:", "127.0.0.1"},
+				{"ip::", "127.0.0.1"},
+				{"ip", "::1"},
+				{"ip:", "::1"},
+				{"ip::", "::1"},
+				{"ip4", "127.0.0.1"},
+				{"ip4:", "127.0.0.1"},
+				{"ip4::", "127.0.0.1"},
+				{"ip6", "::1"},
+				{"ip6:", "::1"},
+				{"ip6::", "::1"},
+			},
+			shouldFail: true,
+		},
+	}
+	if testableNetwork("ip") {
+		priv := test{shouldFail: false}
+		for _, tt := range []struct {
+			network, address string
+			args             [2]string
+		}{
+			{"ip4:47", "127.0.0.1", [2]string{"ip4:47", "127.0.0.1"}},
+			{"ip6:47", "::1", [2]string{"ip6:47", "::1"}},
+		} {
+			c, err := ListenPacket(tt.network, tt.address)
+			if err != nil {
+				continue
+			}
+			c.Close()
+			priv.argLists = append(priv.argLists, tt.args)
+		}
+		if len(priv.argLists) > 0 {
+			tests = append(tests, priv)
+		}
+	}
+
+	for _, tt := range tests {
+		for _, args := range tt.argLists {
+			_, err := Dial(args[0], args[1])
+			if tt.shouldFail != (err != nil) {
+				t.Errorf("Dial(%q, %q) = %v; want (err != nil) is %t", args[0], args[1], err, tt.shouldFail)
+			}
+			_, err = ListenPacket(args[0], args[1])
+			if tt.shouldFail != (err != nil) {
+				t.Errorf("ListenPacket(%q, %q) = %v; want (err != nil) is %t", args[0], args[1], err, tt.shouldFail)
+			}
+			a, err := ResolveIPAddr("ip", args[1])
+			if err != nil {
+				t.Errorf("ResolveIPAddr(\"ip\", %q) = %v", args[1], err)
+				continue
+			}
+			_, err = DialIP(args[0], nil, a)
+			if tt.shouldFail != (err != nil) {
+				t.Errorf("DialIP(%q, %v) = %v; want (err != nil) is %t", args[0], a, err, tt.shouldFail)
+			}
+			_, err = ListenIP(args[0], a)
+			if tt.shouldFail != (err != nil) {
+				t.Errorf("ListenIP(%q, %v) = %v; want (err != nil) is %t", args[0], a, err, tt.shouldFail)
+			}
+		}
+	}
+}
diff --git a/libgo/go/net/ipsock.go b/libgo/go/net/ipsock.go
index f1394a7..947bdf3 100644
--- a/libgo/go/net/ipsock.go
+++ b/libgo/go/net/ipsock.go
@@ -2,12 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Internet protocol family sockets
-
 package net
 
 import (
 	"context"
+	"sync"
 )
 
 // BUG(rsc,mikio): On DragonFly BSD and OpenBSD, listening on the
@@ -17,25 +16,41 @@
 // both address families are to be supported.
 // See inet6(4) for details.
 
-var (
-	// supportsIPv4 reports whether the platform supports IPv4
-	// networking functionality.
-	supportsIPv4 bool
+type ipStackCapabilities struct {
+	sync.Once             // guards following
+	ipv4Enabled           bool
+	ipv6Enabled           bool
+	ipv4MappedIPv6Enabled bool
+}
 
-	// supportsIPv6 reports whether the platform supports IPv6
-	// networking functionality.
-	supportsIPv6 bool
+var ipStackCaps ipStackCapabilities
 
-	// supportsIPv4map reports whether the platform supports
-	// mapping an IPv4 address inside an IPv6 address at transport
-	// layer protocols. See RFC 4291, RFC 4038 and RFC 3493.
-	supportsIPv4map bool
-)
+// supportsIPv4 reports whether the platform supports IPv4 networking
+// functionality.
+func supportsIPv4() bool {
+	ipStackCaps.Once.Do(ipStackCaps.probe)
+	return ipStackCaps.ipv4Enabled
+}
+
+// supportsIPv6 reports whether the platform supports IPv6 networking
+// functionality.
+func supportsIPv6() bool {
+	ipStackCaps.Once.Do(ipStackCaps.probe)
+	return ipStackCaps.ipv6Enabled
+}
+
+// supportsIPv4map reports whether the platform supports mapping an
+// IPv4 address inside an IPv6 address at transport layer
+// protocols. See RFC 4291, RFC 4038 and RFC 3493.
+func supportsIPv4map() bool {
+	ipStackCaps.Once.Do(ipStackCaps.probe)
+	return ipStackCaps.ipv4MappedIPv6Enabled
+}
 
 // An addrList represents a list of network endpoint addresses.
 type addrList []Addr
 
-// isIPv4 returns true if the Addr contains an IPv4 address.
+// isIPv4 reports whether addr contains an IPv4 address.
 func isIPv4(addr Addr) bool {
 	switch addr := addr.(type) {
 	case *TCPAddr:
@@ -48,6 +63,28 @@
 	return false
 }
 
+// isNotIPv4 reports whether addr does not contain an IPv4 address.
+func isNotIPv4(addr Addr) bool { return !isIPv4(addr) }
+
+// forResolve returns the most appropriate address in address for
+// a call to ResolveTCPAddr, ResolveUDPAddr, or ResolveIPAddr.
+// IPv4 is preferred, unless addr contains an IPv6 literal.
+func (addrs addrList) forResolve(network, addr string) Addr {
+	var want6 bool
+	switch network {
+	case "ip":
+		// IPv6 literal (addr does NOT contain a port)
+		want6 = count(addr, ':') > 0
+	case "tcp", "udp":
+		// IPv6 literal. (addr contains a port, so look for '[')
+		want6 = count(addr, '[') > 0
+	}
+	if want6 {
+		return addrs.first(isNotIPv4)
+	}
+	return addrs.first(isIPv4)
+}
+
 // first returns the first address which satisfies strategy, or if
 // none do, then the first address of any kind.
 func (addrs addrList) first(strategy func(Addr) bool) Addr {
@@ -107,10 +144,14 @@
 }
 
 // SplitHostPort splits a network address of the form "host:port",
-// "[host]:port" or "[ipv6-host%zone]:port" into host or
-// ipv6-host%zone and port. A literal address or host name for IPv6
-// must be enclosed in square brackets, as in "[::1]:80",
-// "[ipv6-host]:http" or "[ipv6-host%zone]:80".
+// "host%zone:port", "[host]:port" or "[host%zone]:port" into host or
+// host%zone and port.
+//
+// A literal IPv6 address in hostport must be enclosed in square
+// brackets, as in "[::1]:80", "[::1%lo0]:80".
+//
+// See func Dial for a description of the hostport parameter, and host
+// and port results.
 func SplitHostPort(hostport string) (host, port string, err error) {
 	const (
 		missingPort   = "missing port in address"
@@ -154,9 +195,6 @@
 		if byteIndex(host, ':') >= 0 {
 			return addrErr(hostport, tooManyColons)
 		}
-		if byteIndex(host, '%') >= 0 {
-			return addrErr(hostport, "missing brackets in address")
-		}
 	}
 	if byteIndex(hostport[j:], '[') >= 0 {
 		return addrErr(hostport, "unexpected '[' in address")
@@ -181,11 +219,14 @@
 }
 
 // JoinHostPort combines host and port into a network address of the
-// form "host:port" or, if host contains a colon or a percent sign,
-// "[host]:port".
+// form "host:port". If host contains a colon, as found in literal
+// IPv6 addresses, then JoinHostPort returns "[host]:port".
+//
+// See func Dial for a description of the host and port parameters.
 func JoinHostPort(host, port string) string {
-	// If host has colons or a percent sign, have to bracket it.
-	if byteIndex(host, ':') >= 0 || byteIndex(host, '%') >= 0 {
+	// We assume that host is a literal IPv6 address if host has
+	// colons.
+	if byteIndex(host, ':') >= 0 {
 		return "[" + host + "]:" + port
 	}
 	return host + ":" + port
@@ -240,6 +281,13 @@
 		ips = []IPAddr{{IP: ip}}
 	} else if ip, zone := parseIPv6(host, true); ip != nil {
 		ips = []IPAddr{{IP: ip, Zone: zone}}
+		// Issue 18806: if the machine has halfway configured
+		// IPv6 such that it can bind on "::" (IPv6unspecified)
+		// but not connect back to that same address, fall
+		// back to dialing 0.0.0.0.
+		if ip.Equal(IPv6unspecified) {
+			ips = append(ips, IPAddr{IP: IPv4zero})
+		}
 	} else {
 		// Try as a DNS name.
 		ips, err = r.LookupIPAddr(ctx, host)
diff --git a/libgo/go/net/ipsock_plan9.go b/libgo/go/net/ipsock_plan9.go
index b7fd344..312e4ad 100644
--- a/libgo/go/net/ipsock_plan9.go
+++ b/libgo/go/net/ipsock_plan9.go
@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Internet protocol family sockets for Plan 9
-
 package net
 
 import (
@@ -12,12 +10,25 @@
 	"syscall"
 )
 
+// Probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
+// capabilities.
+//
+// Plan 9 uses IPv6 natively, see ip(3).
+func (p *ipStackCapabilities) probe() {
+	p.ipv4Enabled = probe(netdir+"/iproute", "4i")
+	p.ipv6Enabled = probe(netdir+"/iproute", "6i")
+	if p.ipv4Enabled && p.ipv6Enabled {
+		p.ipv4MappedIPv6Enabled = true
+	}
+}
+
 func probe(filename, query string) bool {
 	var file *file
 	var err error
 	if file, err = open(filename); err != nil {
 		return false
 	}
+	defer file.close()
 
 	r := false
 	for line, ok := file.readLine(); ok && !r; line, ok = file.readLine() {
@@ -32,27 +43,9 @@
 			}
 		}
 	}
-	file.close()
 	return r
 }
 
-func probeIPv4Stack() bool {
-	return probe(netdir+"/iproute", "4i")
-}
-
-// probeIPv6Stack returns two boolean values. If the first boolean
-// value is true, kernel supports basic IPv6 functionality. If the
-// second boolean value is true, kernel supports IPv6 IPv4-mapping.
-func probeIPv6Stack() (supportsIPv6, supportsIPv4map bool) {
-	// Plan 9 uses IPv6 natively, see ip(3).
-	r := probe(netdir+"/iproute", "6i")
-	v := false
-	if r {
-		v = probe(netdir+"/iproute", "4i")
-	}
-	return r, v
-}
-
 // parsePlan9Addr parses address of the form [ip!]port (e.g. 127.0.0.1!80).
 func parsePlan9Addr(s string) (ip IP, iport int, err error) {
 	addr := IPv4zero // address contains port only
@@ -249,10 +242,10 @@
 
 func (fd *netFD) acceptPlan9() (nfd *netFD, err error) {
 	defer func() { fixErr(err) }()
-	if err := fd.readLock(); err != nil {
+	if err := fd.pfd.ReadLock(); err != nil {
 		return nil, err
 	}
-	defer fd.readUnlock()
+	defer fd.pfd.ReadUnlock()
 	listen, err := os.Open(fd.dir + "/listen")
 	if err != nil {
 		return nil, err
diff --git a/libgo/go/net/ipsock_posix.go b/libgo/go/net/ipsock_posix.go
index 05bf939..4b4363a 100644
--- a/libgo/go/net/ipsock_posix.go
+++ b/libgo/go/net/ipsock_posix.go
@@ -8,35 +8,29 @@
 
 import (
 	"context"
+	"internal/poll"
 	"runtime"
 	"syscall"
 )
 
-func probeIPv4Stack() bool {
+// Probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
+// capabilities which are controlled by the IPV6_V6ONLY socket option
+// and kernel configuration.
+//
+// Should we try to use the IPv4 socket interface if we're only
+// dealing with IPv4 sockets? As long as the host system understands
+// IPv4-mapped IPv6, it's okay to pass IPv4-mapeed IPv6 addresses to
+// the IPv6 interface. That simplifies our code and is most
+// general. Unfortunately, we need to run on kernels built without
+// IPv6 support too. So probe the kernel to figure it out.
+func (p *ipStackCapabilities) probe() {
 	s, err := socketFunc(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
 	switch err {
 	case syscall.EAFNOSUPPORT, syscall.EPROTONOSUPPORT:
-		return false
 	case nil:
-		closeFunc(s)
+		poll.CloseFunc(s)
+		p.ipv4Enabled = true
 	}
-	return true
-}
-
-// Should we try to use the IPv4 socket interface if we're
-// only dealing with IPv4 sockets?  As long as the host system
-// understands IPv6, it's okay to pass IPv4 addresses to the IPv6
-// interface. That simplifies our code and is most general.
-// Unfortunately, we need to run on kernels built without IPv6
-// support too. So probe the kernel to figure it out.
-//
-// probeIPv6Stack probes both basic IPv6 capability and IPv6 IPv4-
-// mapping capability which is controlled by IPV6_V6ONLY socket
-// option and/or kernel state "net.inet6.ip6.v6only".
-// It returns two boolean values. If the first boolean value is
-// true, kernel supports basic IPv6 functionality. If the second
-// boolean value is true, kernel supports IPv6 IPv4-mapping.
-func probeIPv6Stack() (supportsIPv6, supportsIPv4map bool) {
 	var probes = []struct {
 		laddr TCPAddr
 		value int
@@ -46,29 +40,19 @@
 		// IPv4-mapped IPv6 address communication capability
 		{laddr: TCPAddr{IP: IPv4(127, 0, 0, 1)}, value: 0},
 	}
-	var supps [2]bool
 	switch runtime.GOOS {
 	case "dragonfly", "openbsd":
-		// Some released versions of DragonFly BSD pretend to
-		// accept IPV6_V6ONLY=0 successfully, but the state
-		// still stays IPV6_V6ONLY=1. Eventually DragonFly BSD
-		// stops pretending, but the transition period would
-		// cause unpredictable behavior and we need to avoid
-		// it.
-		//
-		// OpenBSD also doesn't support IPV6_V6ONLY=0 but it
-		// never pretends to accept IPV6_V6OLY=0. It always
-		// returns an error and we don't need to probe the
-		// capability.
+		// The latest DragonFly BSD and OpenBSD kernels don't
+		// support IPV6_V6ONLY=0. They always return an error
+		// and we don't need to probe the capability.
 		probes = probes[:1]
 	}
-
 	for i := range probes {
 		s, err := socketFunc(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
 		if err != nil {
 			continue
 		}
-		defer closeFunc(s)
+		defer poll.CloseFunc(s)
 		syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, probes[i].value)
 		sa, err := probes[i].laddr.sockaddr(syscall.AF_INET6)
 		if err != nil {
@@ -77,51 +61,55 @@
 		if err := syscall.Bind(s, sa); err != nil {
 			continue
 		}
-		supps[i] = true
+		if i == 0 {
+			p.ipv6Enabled = true
+		} else {
+			p.ipv4MappedIPv6Enabled = true
+		}
 	}
-
-	return supps[0], supps[1]
 }
 
-// favoriteAddrFamily returns the appropriate address family to
-// the given net, laddr, raddr and mode. At first it figures
-// address family out from the net. If mode indicates "listen"
-// and laddr is a wildcard, it assumes that the user wants to
-// make a passive connection with a wildcard address family, both
-// AF_INET and AF_INET6, and a wildcard address like following:
+// favoriteAddrFamily returns the appropriate address family for the
+// given network, laddr, raddr and mode.
 //
-//	1. A wild-wild listen, "tcp" + ""
-//	If the platform supports both IPv6 and IPv6 IPv4-mapping
-//	capabilities, or does not support IPv4, we assume that
-//	the user wants to listen on both IPv4 and IPv6 wildcard
-//	addresses over an AF_INET6 socket with IPV6_V6ONLY=0.
-//	Otherwise we prefer an IPv4 wildcard address listen over
-//	an AF_INET socket.
+// If mode indicates "listen" and laddr is a wildcard, we assume that
+// the user wants to make a passive-open connection with a wildcard
+// address family, both AF_INET and AF_INET6, and a wildcard address
+// like the following:
 //
-//	2. A wild-ipv4wild listen, "tcp" + "0.0.0.0"
-//	Same as 1.
+//	- A listen for a wildcard communication domain, "tcp" or
+//	  "udp", with a wildcard address: If the platform supports
+//	  both IPv6 and IPv4-mapped IPv6 communication capabilities,
+//	  or does not support IPv4, we use a dual stack, AF_INET6 and
+//	  IPV6_V6ONLY=0, wildcard address listen. The dual stack
+//	  wildcard address listen may fall back to an IPv6-only,
+//	  AF_INET6 and IPV6_V6ONLY=1, wildcard address listen.
+//	  Otherwise we prefer an IPv4-only, AF_INET, wildcard address
+//	  listen.
 //
-//	3. A wild-ipv6wild listen, "tcp" + "[::]"
-//	Almost same as 1 but we prefer an IPv6 wildcard address
-//	listen over an AF_INET6 socket with IPV6_V6ONLY=0 when
-//	the platform supports IPv6 capability but not IPv6 IPv4-
-//	mapping capability.
+//	- A listen for a wildcard communication domain, "tcp" or
+//	  "udp", with an IPv4 wildcard address: same as above.
 //
-//	4. A ipv4-ipv4wild listen, "tcp4" + "" or "0.0.0.0"
-//	We use an IPv4 (AF_INET) wildcard address listen.
+//	- A listen for a wildcard communication domain, "tcp" or
+//	  "udp", with an IPv6 wildcard address: same as above.
 //
-//	5. A ipv6-ipv6wild listen, "tcp6" + "" or "[::]"
-//	We use an IPv6 (AF_INET6, IPV6_V6ONLY=1) wildcard address
-//	listen.
+//	- A listen for an IPv4 communication domain, "tcp4" or "udp4",
+//	  with an IPv4 wildcard address: We use an IPv4-only, AF_INET,
+//	  wildcard address listen.
 //
-// Otherwise guess: if the addresses are IPv4 then returns AF_INET,
-// or else returns AF_INET6.  It also returns a boolean value what
+//	- A listen for an IPv6 communication domain, "tcp6" or "udp6",
+//	  with an IPv6 wildcard address: We use an IPv6-only, AF_INET6
+//	  and IPV6_V6ONLY=1, wildcard address listen.
+//
+// Otherwise guess: If the addresses are IPv4 then returns AF_INET,
+// or else returns AF_INET6. It also returns a boolean value what
 // designates IPV6_V6ONLY option.
 //
-// Note that OpenBSD allows neither "net.inet6.ip6.v6only=1" change
-// nor IPPROTO_IPV6 level IPV6_V6ONLY socket option setting.
-func favoriteAddrFamily(net string, laddr, raddr sockaddr, mode string) (family int, ipv6only bool) {
-	switch net[len(net)-1] {
+// Note that the latest DragonFly BSD and OpenBSD kernels allow
+// neither "net.inet6.ip6.v6only=1" change nor IPPROTO_IPV6 level
+// IPV6_V6ONLY socket option setting.
+func favoriteAddrFamily(network string, laddr, raddr sockaddr, mode string) (family int, ipv6only bool) {
+	switch network[len(network)-1] {
 	case '4':
 		return syscall.AF_INET, false
 	case '6':
@@ -129,7 +117,7 @@
 	}
 
 	if mode == "listen" && (laddr == nil || laddr.isWildcard()) {
-		if supportsIPv4map || !supportsIPv4 {
+		if supportsIPv4map() || !supportsIPv4() {
 			return syscall.AF_INET6, false
 		}
 		if laddr == nil {
@@ -145,7 +133,6 @@
 	return syscall.AF_INET6, false
 }
 
-// Internet sockets (TCP, UDP, IP)
 func internetSocket(ctx context.Context, net string, laddr, raddr sockaddr, sotype, proto int, mode string) (fd *netFD, err error) {
 	if (runtime.GOOS == "windows" || runtime.GOOS == "openbsd" || runtime.GOOS == "nacl") && mode == "dial" && raddr.isWildcard() {
 		raddr = raddr.toLocal(net)
@@ -187,7 +174,7 @@
 		if ip6 == nil {
 			return nil, &AddrError{Err: "non-IPv6 address", Addr: ip.String()}
 		}
-		sa := &syscall.SockaddrInet6{Port: port, ZoneId: uint32(zoneToInt(zone))}
+		sa := &syscall.SockaddrInet6{Port: port, ZoneId: uint32(zoneCache.index(zone))}
 		copy(sa.Addr[:], ip6)
 		return sa, nil
 	}
diff --git a/libgo/go/net/ipsock_test.go b/libgo/go/net/ipsock_test.go
index 1d0f00f..aede354 100644
--- a/libgo/go/net/ipsock_test.go
+++ b/libgo/go/net/ipsock_test.go
@@ -215,7 +215,7 @@
 }
 
 func TestAddrList(t *testing.T) {
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
diff --git a/libgo/go/net/listen_test.go b/libgo/go/net/listen_test.go
index 6037f36..21ad446 100644
--- a/libgo/go/net/listen_test.go
+++ b/libgo/go/net/listen_test.go
@@ -225,7 +225,7 @@
 	case "nacl", "plan9":
 		t.Skipf("not supported on %s", runtime.GOOS)
 	}
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -235,7 +235,7 @@
 			continue
 		}
 
-		if !supportsIPv4map && differentWildcardAddr(tt.address1, tt.address2) {
+		if !supportsIPv4map() && differentWildcardAddr(tt.address1, tt.address2) {
 			tt.xerr = nil
 		}
 		var firstErr, secondErr error
@@ -315,7 +315,7 @@
 	case "nacl", "plan9":
 		t.Skipf("not supported on %s", runtime.GOOS)
 	}
-	if !supportsIPv4 || !supportsIPv6 {
+	if !supportsIPv4() || !supportsIPv6() {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -325,7 +325,7 @@
 			continue
 		}
 
-		if !supportsIPv4map && differentWildcardAddr(tt.address1, tt.address2) {
+		if !supportsIPv4map() && differentWildcardAddr(tt.address1, tt.address2) {
 			tt.xerr = nil
 		}
 		var firstErr, secondErr error
@@ -454,7 +454,7 @@
 		// and IPv6 IPv4-mapping capability, we can assume
 		// that the node listens on a wildcard address with an
 		// AF_INET6 socket.
-		if supportsIPv4map && fd.laddr.(*TCPAddr).isWildcard() {
+		if supportsIPv4map() && fd.laddr.(*TCPAddr).isWildcard() {
 			if fd.family != syscall.AF_INET6 {
 				return fmt.Errorf("Listen(%s, %v) returns %v; want %v", fd.net, fd.laddr, fd.family, syscall.AF_INET6)
 			}
@@ -468,7 +468,7 @@
 		// and IPv6 IPv4-mapping capability, we can assume
 		// that the node listens on a wildcard address with an
 		// AF_INET6 socket.
-		if supportsIPv4map && fd.laddr.(*UDPAddr).isWildcard() {
+		if supportsIPv4map() && fd.laddr.(*UDPAddr).isWildcard() {
 			if fd.family != syscall.AF_INET6 {
 				return fmt.Errorf("ListenPacket(%s, %v) returns %v; want %v", fd.net, fd.laddr, fd.family, syscall.AF_INET6)
 			}
@@ -535,7 +535,7 @@
 	case "solaris":
 		t.Skipf("not supported on solaris, see golang.org/issue/7399")
 	}
-	if !supportsIPv4 {
+	if !supportsIPv4() {
 		t.Skip("IPv4 is not supported")
 	}
 
@@ -610,7 +610,7 @@
 	case "solaris":
 		t.Skipf("not supported on solaris, see issue 7399")
 	}
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		t.Skip("IPv6 is not supported")
 	}
 	if os.Getuid() != 0 {
diff --git a/libgo/go/net/lookup.go b/libgo/go/net/lookup.go
index cc2013e..c9f3270 100644
--- a/libgo/go/net/lookup.go
+++ b/libgo/go/net/lookup.go
@@ -28,6 +28,9 @@
 // services contains minimal mappings between services names and port
 // numbers for platforms that don't have a complete list of port numbers
 // (some Solaris distros, nacl, etc).
+//
+// See https://www.iana.org/assignments/service-names-port-numbers
+//
 // On Unix, this map is augmented by readServices via goLookupPort.
 var services = map[string]map[string]int{
 	"udp": {
@@ -63,7 +66,12 @@
 	return proto, nil
 }
 
-const maxServiceLength = len("mobility-header") + 10 // with room to grow
+// maxPortBufSize is the longest reasonable name of a service
+// (non-numeric port).
+// Currently the longest known IANA-unregistered name is
+// "mobility-header", so we use that length, plus some slop in case
+// something longer is added in the future.
+const maxPortBufSize = len("mobility-header") + 10
 
 func lookupPortMap(network, service string) (port int, error error) {
 	switch network {
@@ -74,7 +82,7 @@
 	}
 
 	if m, ok := services[network]; ok {
-		var lowerService [maxServiceLength]byte
+		var lowerService [maxPortBufSize]byte
 		n := copy(lowerService[:], service)
 		lowerASCIIBytes(lowerService[:n])
 		if port, ok := m[string(lowerService[:n])]; ok && n == len(service) {
@@ -97,6 +105,29 @@
 	// GODEBUG=netdns=go, but scoped to just this resolver.
 	PreferGo bool
 
+	// StrictErrors controls the behavior of temporary errors
+	// (including timeout, socket errors, and SERVFAIL) when using
+	// Go's built-in resolver. For a query composed of multiple
+	// sub-queries (such as an A+AAAA address lookup, or walking the
+	// DNS search list), this option causes such errors to abort the
+	// whole query instead of returning a partial result. This is
+	// not enabled by default because it may affect compatibility
+	// with resolvers that process AAAA queries incorrectly.
+	StrictErrors bool
+
+	// Dial optionally specifies an alternate dialer for use by
+	// Go's built-in DNS resolver to make TCP and UDP connections
+	// to DNS services. The host in the address parameter will
+	// always be a literal IP address and not a host name, and the
+	// port in the address parameter will be a literal port number
+	// and not a service name.
+	// If the Conn returned is also a PacketConn, sent and received DNS
+	// messages must adhere to RFC 1035 section 4.2.1, "UDP usage".
+	// Otherwise, DNS messages transmitted over Conn must adhere
+	// to RFC 7766 section 5, "Transport Protocol Selection".
+	// If nil, the default dialer is used.
+	Dial func(ctx context.Context, network, address string) (Conn, error)
+
 	// TODO(bradfitz): optional interface impl override hook
 	// TODO(bradfitz): Timeout time.Duration?
 }
@@ -164,12 +195,15 @@
 
 	select {
 	case <-ctx.Done():
-		// The DNS lookup timed out for some reason. Force
+		// If the DNS lookup timed out for some reason, force
 		// future requests to start the DNS lookup again
 		// rather than waiting for the current lookup to
 		// complete. See issue 8602.
-		err := mapErr(ctx.Err())
-		lookupGroup.Forget(host)
+		ctxErr := ctx.Err()
+		if ctxErr == context.DeadlineExceeded {
+			lookupGroup.Forget(host)
+		}
+		err := mapErr(ctxErr)
 		if trace != nil && trace.DNSDone != nil {
 			trace.DNSDone(nil, false, err)
 		}
diff --git a/libgo/go/net/lookup_test.go b/libgo/go/net/lookup_test.go
index 36db56a..68a7abe 100644
--- a/libgo/go/net/lookup_test.go
+++ b/libgo/go/net/lookup_test.go
@@ -63,7 +63,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -99,7 +99,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -131,7 +131,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -164,7 +164,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -199,7 +199,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !supportsIPv6 || !*testIPv4 || !*testIPv6 {
+	if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
@@ -220,7 +220,7 @@
 }
 
 func TestLookupIPv6LinkLocalAddr(t *testing.T) {
-	if !supportsIPv6 || !*testIPv6 {
+	if !supportsIPv6() || !*testIPv6 {
 		t.Skip("IPv6 is required")
 	}
 
@@ -256,7 +256,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -283,7 +283,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -315,7 +315,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -450,7 +450,7 @@
 }
 
 func TestLookupDotsWithLocalSource(t *testing.T) {
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
@@ -499,7 +499,7 @@
 		testenv.MustHaveExternalNetwork(t)
 	}
 
-	if !supportsIPv4 || !*testIPv4 {
+	if !supportsIPv4() || !*testIPv4 {
 		t.Skip("IPv4 is required")
 	}
 
diff --git a/libgo/go/net/lookup_unix.go b/libgo/go/net/lookup_unix.go
index f96c8be..2813f14 100644
--- a/libgo/go/net/lookup_unix.go
+++ b/libgo/go/net/lookup_unix.go
@@ -16,28 +16,31 @@
 // readProtocols loads contents of /etc/protocols into protocols map
 // for quick access.
 func readProtocols() {
-	if file, err := open("/etc/protocols"); err == nil {
-		for line, ok := file.readLine(); ok; line, ok = file.readLine() {
-			// tcp    6   TCP    # transmission control protocol
-			if i := byteIndex(line, '#'); i >= 0 {
-				line = line[0:i]
+	file, err := open("/etc/protocols")
+	if err != nil {
+		return
+	}
+	defer file.close()
+
+	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+		// tcp    6   TCP    # transmission control protocol
+		if i := byteIndex(line, '#'); i >= 0 {
+			line = line[0:i]
+		}
+		f := getFields(line)
+		if len(f) < 2 {
+			continue
+		}
+		if proto, _, ok := dtoi(f[1]); ok {
+			if _, ok := protocols[f[0]]; !ok {
+				protocols[f[0]] = proto
 			}
-			f := getFields(line)
-			if len(f) < 2 {
-				continue
-			}
-			if proto, _, ok := dtoi(f[1]); ok {
-				if _, ok := protocols[f[0]]; !ok {
-					protocols[f[0]] = proto
-				}
-				for _, alias := range f[2:] {
-					if _, ok := protocols[alias]; !ok {
-						protocols[alias] = proto
-					}
+			for _, alias := range f[2:] {
+				if _, ok := protocols[alias]; !ok {
+					protocols[alias] = proto
 				}
 			}
 		}
-		file.close()
 	}
 }
 
@@ -48,6 +51,29 @@
 	return lookupProtocolMap(name)
 }
 
+func (r *Resolver) dial(ctx context.Context, network, server string) (dnsConn, error) {
+	// Calling Dial here is scary -- we have to be sure not to
+	// dial a name that will require a DNS lookup, or Dial will
+	// call back here to translate it. The DNS config parser has
+	// already checked that all the cfg.servers are IP
+	// addresses, which Dial will use without a DNS lookup.
+	var c Conn
+	var err error
+	if r.Dial != nil {
+		c, err = r.Dial(ctx, network, server)
+	} else {
+		var d Dialer
+		c, err = d.DialContext(ctx, network, server)
+	}
+	if err != nil {
+		return nil, mapErr(err)
+	}
+	if _, ok := c.(PacketConn); ok {
+		return &dnsPacketConn{c}, nil
+	}
+	return &dnsStreamConn{c}, nil
+}
+
 func (r *Resolver) lookupHost(ctx context.Context, host string) (addrs []string, err error) {
 	order := systemConf().hostLookupOrder(host)
 	if !r.PreferGo && order == hostLookupCgo {
@@ -57,12 +83,12 @@
 		// cgo not available (or netgo); fall back to Go's DNS resolver
 		order = hostLookupFilesDNS
 	}
-	return goLookupHostOrder(ctx, host, order)
+	return r.goLookupHostOrder(ctx, host, order)
 }
 
 func (r *Resolver) lookupIP(ctx context.Context, host string) (addrs []IPAddr, err error) {
 	if r.PreferGo {
-		return goLookupIP(ctx, host)
+		return r.goLookupIP(ctx, host)
 	}
 	order := systemConf().hostLookupOrder(host)
 	if order == hostLookupCgo {
@@ -72,7 +98,7 @@
 		// cgo not available (or netgo); fall back to Go's DNS resolver
 		order = hostLookupFilesDNS
 	}
-	addrs, _, err = goLookupIPCNAMEOrder(ctx, host, order)
+	addrs, _, err = r.goLookupIPCNAMEOrder(ctx, host, order)
 	return
 }
 
@@ -98,17 +124,17 @@
 			return cname, err
 		}
 	}
-	return goLookupCNAME(ctx, name)
+	return r.goLookupCNAME(ctx, name)
 }
 
-func (*Resolver) lookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
+func (r *Resolver) lookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
 	var target string
 	if service == "" && proto == "" {
 		target = name
 	} else {
 		target = "_" + service + "._" + proto + "." + name
 	}
-	cname, rrs, err := lookup(ctx, target, dnsTypeSRV)
+	cname, rrs, err := r.lookup(ctx, target, dnsTypeSRV)
 	if err != nil {
 		return "", nil, err
 	}
@@ -121,8 +147,8 @@
 	return cname, srvs, nil
 }
 
-func (*Resolver) lookupMX(ctx context.Context, name string) ([]*MX, error) {
-	_, rrs, err := lookup(ctx, name, dnsTypeMX)
+func (r *Resolver) lookupMX(ctx context.Context, name string) ([]*MX, error) {
+	_, rrs, err := r.lookup(ctx, name, dnsTypeMX)
 	if err != nil {
 		return nil, err
 	}
@@ -135,8 +161,8 @@
 	return mxs, nil
 }
 
-func (*Resolver) lookupNS(ctx context.Context, name string) ([]*NS, error) {
-	_, rrs, err := lookup(ctx, name, dnsTypeNS)
+func (r *Resolver) lookupNS(ctx context.Context, name string) ([]*NS, error) {
+	_, rrs, err := r.lookup(ctx, name, dnsTypeNS)
 	if err != nil {
 		return nil, err
 	}
@@ -148,7 +174,7 @@
 }
 
 func (r *Resolver) lookupTXT(ctx context.Context, name string) ([]string, error) {
-	_, rrs, err := lookup(ctx, name, dnsTypeTXT)
+	_, rrs, err := r.lookup(ctx, name, dnsTypeTXT)
 	if err != nil {
 		return nil, err
 	}
@@ -165,5 +191,5 @@
 			return ptrs, err
 		}
 	}
-	return goLookupPTR(ctx, addr)
+	return r.goLookupPTR(ctx, addr)
 }
diff --git a/libgo/go/net/lookup_windows.go b/libgo/go/net/lookup_windows.go
index 5808293..0036d89 100644
--- a/libgo/go/net/lookup_windows.go
+++ b/libgo/go/net/lookup_windows.go
@@ -107,7 +107,7 @@
 				addrs = append(addrs, IPAddr{IP: IPv4(a[0], a[1], a[2], a[3])})
 			case syscall.AF_INET6:
 				a := (*syscall.RawSockaddrInet6)(addr).Addr
-				zone := zoneToString(int((*syscall.RawSockaddrInet6)(addr).Scope_id))
+				zone := zoneCache.name(int((*syscall.RawSockaddrInet6)(addr).Scope_id))
 				addrs = append(addrs, IPAddr{IP: IP{a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], a[10], a[11], a[12], a[13], a[14], a[15]}, Zone: zone})
 			default:
 				ch <- ret{err: &DNSError{Err: syscall.EWINDOWS.Error(), Name: name}}
diff --git a/libgo/go/net/mail/message.go b/libgo/go/net/mail/message.go
index 702b765..45a995e 100644
--- a/libgo/go/net/mail/message.go
+++ b/libgo/go/net/mail/message.go
@@ -49,7 +49,7 @@
 
 // ReadMessage reads a message from r.
 // The headers are parsed, and the body of the message will be available
-// for reading from r.
+// for reading from msg.Body.
 func ReadMessage(r io.Reader) (msg *Message, err error) {
 	tp := textproto.NewReader(bufio.NewReader(r))
 
@@ -387,13 +387,15 @@
 	debug.Printf("consumePhrase: [%s]", p.s)
 	// phrase = 1*word
 	var words []string
+	var isPrevEncoded bool
 	for {
 		// word = atom / quoted-string
 		var word string
 		p.skipSpace()
 		if p.empty() {
-			return "", errors.New("mail: missing phrase")
+			break
 		}
+		isEncoded := false
 		if p.peek() == '"' {
 			// quoted-string
 			word, err = p.consumeQuotedString()
@@ -403,7 +405,7 @@
 			// than what RFC 5322 specifies.
 			word, err = p.consumeAtom(true, true)
 			if err == nil {
-				word, err = p.decodeRFC2047Word(word)
+				word, isEncoded, err = p.decodeRFC2047Word(word)
 			}
 		}
 
@@ -411,7 +413,12 @@
 			break
 		}
 		debug.Printf("consumePhrase: consumed %q", word)
-		words = append(words, word)
+		if isPrevEncoded && isEncoded {
+			words[len(words)-1] += word
+		} else {
+			words = append(words, word)
+		}
+		isPrevEncoded = isEncoded
 	}
 	// Ignore any error if we got at least one word.
 	if err != nil && len(words) == 0 {
@@ -540,22 +547,23 @@
 	return len(p.s)
 }
 
-func (p *addrParser) decodeRFC2047Word(s string) (string, error) {
+func (p *addrParser) decodeRFC2047Word(s string) (word string, isEncoded bool, err error) {
 	if p.dec != nil {
-		return p.dec.DecodeHeader(s)
+		word, err = p.dec.Decode(s)
+	} else {
+		word, err = rfc2047Decoder.Decode(s)
 	}
 
-	dec, err := rfc2047Decoder.Decode(s)
 	if err == nil {
-		return dec, nil
+		return word, true, nil
 	}
 
 	if _, ok := err.(charsetError); ok {
-		return s, err
+		return s, true, err
 	}
 
 	// Ignore invalid RFC 2047 encoded-word errors.
-	return s, nil
+	return s, false, nil
 }
 
 var rfc2047Decoder = mime.WordDecoder{
diff --git a/libgo/go/net/mail/message_test.go b/libgo/go/net/mail/message_test.go
index f0761ab..2106a0b 100644
--- a/libgo/go/net/mail/message_test.go
+++ b/libgo/go/net/mail/message_test.go
@@ -136,6 +136,7 @@
 		4: {"\"\\" + string([]byte{0x80}) + "\" <escaped-invalid-unicode@example.net>", "invalid utf-8 in quoted-string"},
 		5: {"\"\x00\" <null@example.net>", "bad character in quoted-string"},
 		6: {"\"\\\x00\" <escaped-null@example.net>", "bad character in quoted-string"},
+		7: {"John Doe", "no angle-addr"},
 	}
 
 	for i, tc := range mustErrTestCases {
@@ -235,6 +236,16 @@
 				},
 			},
 		},
+		// RFC 2047 "Q"-encoded UTF-8 address with multiple encoded-words.
+		{
+			`=?utf-8?q?J=C3=B6rg?=  =?utf-8?q?Doe?= <joerg@example.com>`,
+			[]*Address{
+				{
+					Name:    `JörgDoe`,
+					Address: "joerg@example.com",
+				},
+			},
+		},
 		// RFC 2047, Section 8.
 		{
 			`=?ISO-8859-1?Q?Andr=E9?= Pirard <PIRARD@vm1.ulg.ac.be>`,
diff --git a/libgo/go/net/main_cloexec_test.go b/libgo/go/net/main_cloexec_test.go
index 7903819..fa1ed02 100644
--- a/libgo/go/net/main_cloexec_test.go
+++ b/libgo/go/net/main_cloexec_test.go
@@ -2,10 +2,12 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build freebsd linux
+// +build dragonfly freebsd linux
 
 package net
 
+import "internal/poll"
+
 func init() {
 	extraTestHookInstallers = append(extraTestHookInstallers, installAccept4TestHook)
 	extraTestHookUninstallers = append(extraTestHookUninstallers, uninstallAccept4TestHook)
@@ -13,13 +15,13 @@
 
 var (
 	// Placeholders for saving original socket system calls.
-	origAccept4 = accept4Func
+	origAccept4 = poll.Accept4Func
 )
 
 func installAccept4TestHook() {
-	accept4Func = sw.Accept4
+	poll.Accept4Func = sw.Accept4
 }
 
 func uninstallAccept4TestHook() {
-	accept4Func = origAccept4
+	poll.Accept4Func = origAccept4
 }
diff --git a/libgo/go/net/main_test.go b/libgo/go/net/main_test.go
index 28a8ff6..3e7a85a 100644
--- a/libgo/go/net/main_test.go
+++ b/libgo/go/net/main_test.go
@@ -70,7 +70,7 @@
 )
 
 func setupTestData() {
-	if supportsIPv4 {
+	if supportsIPv4() {
 		resolveTCPAddrTests = append(resolveTCPAddrTests, []resolveTCPAddrTest{
 			{"tcp", "localhost:1", &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 1}, nil},
 			{"tcp4", "localhost:2", &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 2}, nil},
@@ -85,25 +85,31 @@
 		}...)
 	}
 
-	if supportsIPv6 {
+	if supportsIPv6() {
 		resolveTCPAddrTests = append(resolveTCPAddrTests, resolveTCPAddrTest{"tcp6", "localhost:3", &TCPAddr{IP: IPv6loopback, Port: 3}, nil})
 		resolveUDPAddrTests = append(resolveUDPAddrTests, resolveUDPAddrTest{"udp6", "localhost:3", &UDPAddr{IP: IPv6loopback, Port: 3}, nil})
 		resolveIPAddrTests = append(resolveIPAddrTests, resolveIPAddrTest{"ip6", "localhost", &IPAddr{IP: IPv6loopback}, nil})
+
+		// Issue 20911: don't return IPv4 addresses for
+		// Resolve*Addr calls of the IPv6 unspecified address.
+		resolveTCPAddrTests = append(resolveTCPAddrTests, resolveTCPAddrTest{"tcp", "[::]:4", &TCPAddr{IP: IPv6unspecified, Port: 4}, nil})
+		resolveUDPAddrTests = append(resolveUDPAddrTests, resolveUDPAddrTest{"udp", "[::]:4", &UDPAddr{IP: IPv6unspecified, Port: 4}, nil})
+		resolveIPAddrTests = append(resolveIPAddrTests, resolveIPAddrTest{"ip", "::", &IPAddr{IP: IPv6unspecified}, nil})
 	}
 
 	ifi := loopbackInterface()
 	if ifi != nil {
 		index := fmt.Sprintf("%v", ifi.Index)
 		resolveTCPAddrTests = append(resolveTCPAddrTests, []resolveTCPAddrTest{
-			{"tcp6", "[fe80::1%" + ifi.Name + "]:1", &TCPAddr{IP: ParseIP("fe80::1"), Port: 1, Zone: zoneToString(ifi.Index)}, nil},
+			{"tcp6", "[fe80::1%" + ifi.Name + "]:1", &TCPAddr{IP: ParseIP("fe80::1"), Port: 1, Zone: zoneCache.name(ifi.Index)}, nil},
 			{"tcp6", "[fe80::1%" + index + "]:2", &TCPAddr{IP: ParseIP("fe80::1"), Port: 2, Zone: index}, nil},
 		}...)
 		resolveUDPAddrTests = append(resolveUDPAddrTests, []resolveUDPAddrTest{
-			{"udp6", "[fe80::1%" + ifi.Name + "]:1", &UDPAddr{IP: ParseIP("fe80::1"), Port: 1, Zone: zoneToString(ifi.Index)}, nil},
+			{"udp6", "[fe80::1%" + ifi.Name + "]:1", &UDPAddr{IP: ParseIP("fe80::1"), Port: 1, Zone: zoneCache.name(ifi.Index)}, nil},
 			{"udp6", "[fe80::1%" + index + "]:2", &UDPAddr{IP: ParseIP("fe80::1"), Port: 2, Zone: index}, nil},
 		}...)
 		resolveIPAddrTests = append(resolveIPAddrTests, []resolveIPAddrTest{
-			{"ip6", "fe80::1%" + ifi.Name, &IPAddr{IP: ParseIP("fe80::1"), Zone: zoneToString(ifi.Index)}, nil},
+			{"ip6", "fe80::1%" + ifi.Name, &IPAddr{IP: ParseIP("fe80::1"), Zone: zoneCache.name(ifi.Index)}, nil},
 			{"ip6", "fe80::1%" + index, &IPAddr{IP: ParseIP("fe80::1"), Zone: index}, nil},
 		}...)
 	}
diff --git a/libgo/go/net/main_unix_test.go b/libgo/go/net/main_unix_test.go
index 8c8f944..34a8a10 100644
--- a/libgo/go/net/main_unix_test.go
+++ b/libgo/go/net/main_unix_test.go
@@ -6,13 +6,15 @@
 
 package net
 
+import "internal/poll"
+
 var (
 	// Placeholders for saving original socket system calls.
 	origSocket        = socketFunc
-	origClose         = closeFunc
+	origClose         = poll.CloseFunc
 	origConnect       = connectFunc
 	origListen        = listenFunc
-	origAccept        = acceptFunc
+	origAccept        = poll.AcceptFunc
 	origGetsockoptInt = getsockoptIntFunc
 
 	extraTestHookInstallers   []func()
@@ -21,10 +23,10 @@
 
 func installTestHooks() {
 	socketFunc = sw.Socket
-	closeFunc = sw.Close
+	poll.CloseFunc = sw.Close
 	connectFunc = sw.Connect
 	listenFunc = sw.Listen
-	acceptFunc = sw.Accept
+	poll.AcceptFunc = sw.Accept
 	getsockoptIntFunc = sw.GetsockoptInt
 
 	for _, fn := range extraTestHookInstallers {
@@ -34,10 +36,10 @@
 
 func uninstallTestHooks() {
 	socketFunc = origSocket
-	closeFunc = origClose
+	poll.CloseFunc = origClose
 	connectFunc = origConnect
 	listenFunc = origListen
-	acceptFunc = origAccept
+	poll.AcceptFunc = origAccept
 	getsockoptIntFunc = origGetsockoptInt
 
 	for _, fn := range extraTestHookUninstallers {
@@ -48,6 +50,6 @@
 // forceCloseSockets must be called only from TestMain.
 func forceCloseSockets() {
 	for s := range sw.Sockets() {
-		closeFunc(s)
+		poll.CloseFunc(s)
 	}
 }
diff --git a/libgo/go/net/main_windows_test.go b/libgo/go/net/main_windows_test.go
index 6ea318c..f38a3a0 100644
--- a/libgo/go/net/main_windows_test.go
+++ b/libgo/go/net/main_windows_test.go
@@ -4,37 +4,39 @@
 
 package net
 
+import "internal/poll"
+
 var (
 	// Placeholders for saving original socket system calls.
 	origSocket      = socketFunc
-	origClosesocket = closeFunc
+	origClosesocket = poll.CloseFunc
 	origConnect     = connectFunc
-	origConnectEx   = connectExFunc
+	origConnectEx   = poll.ConnectExFunc
 	origListen      = listenFunc
-	origAccept      = acceptFunc
+	origAccept      = poll.AcceptFunc
 )
 
 func installTestHooks() {
 	socketFunc = sw.Socket
-	closeFunc = sw.Closesocket
+	poll.CloseFunc = sw.Closesocket
 	connectFunc = sw.Connect
-	connectExFunc = sw.ConnectEx
+	poll.ConnectExFunc = sw.ConnectEx
 	listenFunc = sw.Listen
-	acceptFunc = sw.AcceptEx
+	poll.AcceptFunc = sw.AcceptEx
 }
 
 func uninstallTestHooks() {
 	socketFunc = origSocket
-	closeFunc = origClosesocket
+	poll.CloseFunc = origClosesocket
 	connectFunc = origConnect
-	connectExFunc = origConnectEx
+	poll.ConnectExFunc = origConnectEx
 	listenFunc = origListen
-	acceptFunc = origAccept
+	poll.AcceptFunc = origAccept
 }
 
 // forceCloseSockets must be called only from TestMain.
 func forceCloseSockets() {
 	for s := range sw.Sockets() {
-		closeFunc(s)
+		poll.CloseFunc(s)
 	}
 }
diff --git a/libgo/go/net/mockserver_test.go b/libgo/go/net/mockserver_test.go
index 766de6a..44581d9 100644
--- a/libgo/go/net/mockserver_test.go
+++ b/libgo/go/net/mockserver_test.go
@@ -31,20 +31,20 @@
 func newLocalListener(network string) (Listener, error) {
 	switch network {
 	case "tcp":
-		if supportsIPv4 {
+		if supportsIPv4() {
 			if ln, err := Listen("tcp4", "127.0.0.1:0"); err == nil {
 				return ln, nil
 			}
 		}
-		if supportsIPv6 {
+		if supportsIPv6() {
 			return Listen("tcp6", "[::1]:0")
 		}
 	case "tcp4":
-		if supportsIPv4 {
+		if supportsIPv4() {
 			return Listen("tcp4", "127.0.0.1:0")
 		}
 	case "tcp6":
-		if supportsIPv6 {
+		if supportsIPv6() {
 			return Listen("tcp6", "[::1]:0")
 		}
 	case "unix", "unixpacket":
@@ -333,18 +333,18 @@
 func newLocalPacketListener(network string) (PacketConn, error) {
 	switch network {
 	case "udp":
-		if supportsIPv4 {
+		if supportsIPv4() {
 			return ListenPacket("udp4", "127.0.0.1:0")
 		}
-		if supportsIPv6 {
+		if supportsIPv6() {
 			return ListenPacket("udp6", "[::1]:0")
 		}
 	case "udp4":
-		if supportsIPv4 {
+		if supportsIPv4() {
 			return ListenPacket("udp4", "127.0.0.1:0")
 		}
 	case "udp6":
-		if supportsIPv6 {
+		if supportsIPv6() {
 			return ListenPacket("udp6", "[::1]:0")
 		}
 	case "unixgram":
diff --git a/libgo/go/net/net.go b/libgo/go/net/net.go
index a8b5736..91ec048 100644
--- a/libgo/go/net/net.go
+++ b/libgo/go/net/net.go
@@ -81,6 +81,7 @@
 import (
 	"context"
 	"errors"
+	"internal/poll"
 	"io"
 	"os"
 	"syscall"
@@ -95,12 +96,6 @@
 	netCgo bool // set true in conf_netcgo.go for build tag "netcgo"
 )
 
-func init() {
-	sysInit()
-	supportsIPv4 = probeIPv4Stack()
-	supportsIPv6, supportsIPv4map = probeIPv6Stack()
-}
-
 // Addr represents a network end point address.
 //
 // The two methods Network and String conventionally return strings
@@ -234,7 +229,7 @@
 	if !c.ok() {
 		return syscall.EINVAL
 	}
-	if err := c.fd.setDeadline(t); err != nil {
+	if err := c.fd.pfd.SetDeadline(t); err != nil {
 		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
 	}
 	return nil
@@ -245,7 +240,7 @@
 	if !c.ok() {
 		return syscall.EINVAL
 	}
-	if err := c.fd.setReadDeadline(t); err != nil {
+	if err := c.fd.pfd.SetReadDeadline(t); err != nil {
 		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
 	}
 	return nil
@@ -256,7 +251,7 @@
 	if !c.ok() {
 		return syscall.EINVAL
 	}
-	if err := c.fd.setWriteDeadline(t); err != nil {
+	if err := c.fd.pfd.SetWriteDeadline(t); err != nil {
 		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
 	}
 	return nil
@@ -391,10 +386,8 @@
 	errMissingAddress = errors.New("missing address")
 
 	// For both read and write operations.
-	errTimeout          error = &timeoutError{}
-	errCanceled               = errors.New("operation was canceled")
-	errClosing                = errors.New("use of closed network connection")
-	ErrWriteToConnected       = errors.New("use of WriteTo with pre-connected connection")
+	errCanceled         = errors.New("operation was canceled")
+	ErrWriteToConnected = errors.New("use of WriteTo with pre-connected connection")
 )
 
 // mapErr maps from the context errors to the historical internal net
@@ -407,7 +400,7 @@
 	case context.Canceled:
 		return errCanceled
 	case context.DeadlineExceeded:
-		return errTimeout
+		return poll.ErrTimeout
 	default:
 		return err
 	}
@@ -502,12 +495,6 @@
 	return ok && t.Temporary()
 }
 
-type timeoutError struct{}
-
-func (e *timeoutError) Error() string   { return "i/o timeout" }
-func (e *timeoutError) Timeout() bool   { return true }
-func (e *timeoutError) Temporary() bool { return true }
-
 // A ParseError is the error type of literal network address parsers.
 type ParseError struct {
 	// Type is the type of string that was expected, such as
@@ -632,8 +619,6 @@
 	writeBuffers(*Buffers) (int64, error)
 }
 
-var testHookDidWritev = func(wrote int) {}
-
 // Buffers contains zero or more runs of bytes to write.
 //
 // On certain machines, for certain types of connections, this is
diff --git a/libgo/go/net/net_test.go b/libgo/go/net/net_test.go
index 9a9a7e5..024505e 100644
--- a/libgo/go/net/net_test.go
+++ b/libgo/go/net/net_test.go
@@ -54,7 +54,7 @@
 			err = c.CloseRead()
 		}
 		if err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, true); perr != nil {
 				t.Error(perr)
 			}
 			t.Fatal(err)
@@ -94,7 +94,7 @@
 			err = c.CloseWrite()
 		}
 		if err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, true); perr != nil {
 				t.Error(perr)
 			}
 			t.Error(err)
@@ -139,7 +139,7 @@
 			err = c.CloseWrite()
 		}
 		if err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, true); perr != nil {
 				t.Error(perr)
 			}
 			t.Fatal(err)
@@ -184,7 +184,7 @@
 		defer c.Close()
 
 		if err := c.Close(); err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, false); perr != nil {
 				t.Error(perr)
 			}
 			t.Fatal(err)
@@ -215,7 +215,7 @@
 
 		dst := ln.Addr().String()
 		if err := ln.Close(); err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, false); perr != nil {
 				t.Error(perr)
 			}
 			t.Fatal(err)
@@ -269,7 +269,7 @@
 		defer c.Close()
 
 		if err := c.Close(); err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, false); perr != nil {
 				t.Error(perr)
 			}
 			t.Fatal(err)
@@ -292,7 +292,7 @@
 		}
 		addr := ln.Addr().String()
 		if err := ln.Close(); err != nil {
-			if perr := parseCloseError(err); perr != nil {
+			if perr := parseCloseError(err, false); perr != nil {
 				t.Error(perr)
 			}
 			t.Fatal(err)
diff --git a/libgo/go/net/platform_test.go b/libgo/go/net/platform_test.go
index 2a14095..5841ca3 100644
--- a/libgo/go/net/platform_test.go
+++ b/libgo/go/net/platform_test.go
@@ -50,11 +50,11 @@
 	}
 	switch ss[0] {
 	case "tcp4", "udp4", "ip4":
-		if !supportsIPv4 {
+		if !supportsIPv4() {
 			return false
 		}
 	case "tcp6", "udp6", "ip6":
-		if !supportsIPv6 {
+		if !supportsIPv6() {
 			return false
 		}
 	}
@@ -117,25 +117,25 @@
 
 	// Test functionality of IPv4 communication using AF_INET and
 	// IPv6 communication using AF_INET6 sockets.
-	if !supportsIPv4 && ip.To4() != nil {
+	if !supportsIPv4() && ip.To4() != nil {
 		return false
 	}
-	if !supportsIPv6 && ip.To16() != nil && ip.To4() == nil {
+	if !supportsIPv6() && ip.To16() != nil && ip.To4() == nil {
 		return false
 	}
 	cip := ParseIP(client)
 	if cip != nil {
-		if !supportsIPv4 && cip.To4() != nil {
+		if !supportsIPv4() && cip.To4() != nil {
 			return false
 		}
-		if !supportsIPv6 && cip.To16() != nil && cip.To4() == nil {
+		if !supportsIPv6() && cip.To16() != nil && cip.To4() == nil {
 			return false
 		}
 	}
 
 	// Test functionality of IPv4 communication using AF_INET6
 	// sockets.
-	if !supportsIPv4map && supportsIPv4 && (network == "tcp" || network == "udp" || network == "ip") && wildcard {
+	if !supportsIPv4map() && supportsIPv4() && (network == "tcp" || network == "udp" || network == "ip") && wildcard {
 		// At this point, we prefer IPv4 when ip is nil.
 		// See favoriteAddrFamily for further information.
 		if ip.To16() != nil && ip.To4() == nil && cip.To4() != nil { // a pair of IPv6 server and IPv4 client
diff --git a/libgo/go/net/port_unix.go b/libgo/go/net/port_unix.go
index 3120ba1..8dd1c32 100644
--- a/libgo/go/net/port_unix.go
+++ b/libgo/go/net/port_unix.go
@@ -17,6 +17,8 @@
 	if err != nil {
 		return
 	}
+	defer file.close()
+
 	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
 		// "http 80/tcp www www-http # World Wide Web HTTP"
 		if i := byteIndex(line, '#'); i >= 0 {
@@ -43,7 +45,6 @@
 			}
 		}
 	}
-	file.close()
 }
 
 // goLookupPort is the native Go implementation of LookupPort.
diff --git a/libgo/go/net/rawconn.go b/libgo/go/net/rawconn.go
new file mode 100644
index 0000000..d67be64
--- /dev/null
+++ b/libgo/go/net/rawconn.go
@@ -0,0 +1,62 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"runtime"
+	"syscall"
+)
+
+// BUG(mikio): On Windows, the Read and Write methods of
+// syscall.RawConn are not implemented.
+
+// BUG(mikio): On NaCl and Plan 9, the Control, Read and Write methods
+// of syscall.RawConn are not implemented.
+
+type rawConn struct {
+	fd *netFD
+}
+
+func (c *rawConn) ok() bool { return c != nil && c.fd != nil }
+
+func (c *rawConn) Control(f func(uintptr)) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	err := c.fd.pfd.RawControl(f)
+	runtime.KeepAlive(c.fd)
+	if err != nil {
+		err = &OpError{Op: "raw-control", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+	}
+	return err
+}
+
+func (c *rawConn) Read(f func(uintptr) bool) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	err := c.fd.pfd.RawRead(f)
+	runtime.KeepAlive(c.fd)
+	if err != nil {
+		err = &OpError{Op: "raw-read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return err
+}
+
+func (c *rawConn) Write(f func(uintptr) bool) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	err := c.fd.pfd.RawWrite(f)
+	runtime.KeepAlive(c.fd)
+	if err != nil {
+		err = &OpError{Op: "raw-write", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return err
+}
+
+func newRawConn(fd *netFD) (*rawConn, error) {
+	return &rawConn{fd: fd}, nil
+}
diff --git a/libgo/go/net/rawconn_unix_test.go b/libgo/go/net/rawconn_unix_test.go
new file mode 100644
index 0000000..294249b
--- /dev/null
+++ b/libgo/go/net/rawconn_unix_test.go
@@ -0,0 +1,94 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package net
+
+import (
+	"bytes"
+	"syscall"
+	"testing"
+)
+
+func TestRawConn(t *testing.T) {
+	handler := func(ls *localServer, ln Listener) {
+		c, err := ln.Accept()
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		defer c.Close()
+		var b [32]byte
+		n, err := c.Read(b[:])
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		if _, err := c.Write(b[:n]); err != nil {
+			t.Error(err)
+			return
+		}
+	}
+	ls, err := newLocalServer("tcp")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer ls.teardown()
+	if err := ls.buildup(handler); err != nil {
+		t.Fatal(err)
+	}
+
+	c, err := Dial(ls.Listener.Addr().Network(), ls.Listener.Addr().String())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Close()
+	cc, err := c.(*TCPConn).SyscallConn()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var operr error
+	data := []byte("HELLO-R-U-THERE")
+	err = cc.Write(func(s uintptr) bool {
+		_, operr = syscall.Write(int(s), data)
+		if operr == syscall.EAGAIN {
+			return false
+		}
+		return true
+	})
+	if err != nil || operr != nil {
+		t.Fatal(err, operr)
+	}
+
+	var nr int
+	var b [32]byte
+	err = cc.Read(func(s uintptr) bool {
+		nr, operr = syscall.Read(int(s), b[:])
+		if operr == syscall.EAGAIN {
+			return false
+		}
+		return true
+	})
+	if err != nil || operr != nil {
+		t.Fatal(err, operr)
+	}
+	if bytes.Compare(b[:nr], data) != 0 {
+		t.Fatalf("got %#v; want %#v", b[:nr], data)
+	}
+
+	fn := func(s uintptr) {
+		operr = syscall.SetsockoptInt(int(s), syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1)
+	}
+	err = cc.Control(fn)
+	if err != nil || operr != nil {
+		t.Fatal(err, operr)
+	}
+	c.Close()
+	err = cc.Control(fn)
+	if err == nil {
+		t.Fatal("should fail")
+	}
+}
diff --git a/libgo/go/net/rawconn_windows_test.go b/libgo/go/net/rawconn_windows_test.go
new file mode 100644
index 0000000..5fb6de7
--- /dev/null
+++ b/libgo/go/net/rawconn_windows_test.go
@@ -0,0 +1,36 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"syscall"
+	"testing"
+)
+
+func TestRawConn(t *testing.T) {
+	c, err := newLocalPacketListener("udp")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Close()
+	cc, err := c.(*UDPConn).SyscallConn()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var operr error
+	fn := func(s uintptr) {
+		operr = syscall.SetsockoptInt(syscall.Handle(s), syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1)
+	}
+	err = cc.Control(fn)
+	if err != nil || operr != nil {
+		t.Fatal(err, operr)
+	}
+	c.Close()
+	err = cc.Control(fn)
+	if err == nil {
+		t.Fatal("should fail")
+	}
+}
diff --git a/libgo/go/net/rpc/debug.go b/libgo/go/net/rpc/debug.go
index 98b2c1c..a1d799f 100644
--- a/libgo/go/net/rpc/debug.go
+++ b/libgo/go/net/rpc/debug.go
@@ -71,20 +71,17 @@
 // Runs at /debug/rpc
 func (server debugHTTP) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	// Build a sorted version of the data.
-	var services = make(serviceArray, len(server.serviceMap))
-	i := 0
-	server.mu.Lock()
-	for sname, service := range server.serviceMap {
-		services[i] = debugService{service, sname, make(methodArray, len(service.method))}
-		j := 0
-		for mname, method := range service.method {
-			services[i].Method[j] = debugMethod{method, mname}
-			j++
+	var services serviceArray
+	server.serviceMap.Range(func(snamei, svci interface{}) bool {
+		svc := svci.(*service)
+		ds := debugService{svc, snamei.(string), make(methodArray, 0, len(svc.method))}
+		for mname, method := range svc.method {
+			ds.Method = append(ds.Method, debugMethod{method, mname})
 		}
-		sort.Sort(services[i].Method)
-		i++
-	}
-	server.mu.Unlock()
+		sort.Sort(ds.Method)
+		services = append(services, ds)
+		return true
+	})
 	sort.Sort(services)
 	err := debug.Execute(w, services)
 	if err != nil {
diff --git a/libgo/go/net/rpc/jsonrpc/all_test.go b/libgo/go/net/rpc/jsonrpc/all_test.go
index b811d3c..bbb8eb0 100644
--- a/libgo/go/net/rpc/jsonrpc/all_test.go
+++ b/libgo/go/net/rpc/jsonrpc/all_test.go
@@ -13,6 +13,7 @@
 	"io/ioutil"
 	"net"
 	"net/rpc"
+	"reflect"
 	"strings"
 	"testing"
 )
@@ -55,8 +56,26 @@
 	panic("ERROR")
 }
 
+type BuiltinTypes struct{}
+
+func (BuiltinTypes) Map(i int, reply *map[int]int) error {
+	(*reply)[i] = i
+	return nil
+}
+
+func (BuiltinTypes) Slice(i int, reply *[]int) error {
+	*reply = append(*reply, i)
+	return nil
+}
+
+func (BuiltinTypes) Array(i int, reply *[1]int) error {
+	(*reply)[0] = i
+	return nil
+}
+
 func init() {
 	rpc.Register(new(Arith))
+	rpc.Register(BuiltinTypes{})
 }
 
 func TestServerNoParams(t *testing.T) {
@@ -182,6 +201,45 @@
 	}
 }
 
+func TestBuiltinTypes(t *testing.T) {
+	cli, srv := net.Pipe()
+	go ServeConn(srv)
+
+	client := NewClient(cli)
+	defer client.Close()
+
+	// Map
+	arg := 7
+	replyMap := map[int]int{}
+	err := client.Call("BuiltinTypes.Map", arg, &replyMap)
+	if err != nil {
+		t.Errorf("Map: expected no error but got string %q", err.Error())
+	}
+	if replyMap[arg] != arg {
+		t.Errorf("Map: expected %d got %d", arg, replyMap[arg])
+	}
+
+	// Slice
+	replySlice := []int{}
+	err = client.Call("BuiltinTypes.Slice", arg, &replySlice)
+	if err != nil {
+		t.Errorf("Slice: expected no error but got string %q", err.Error())
+	}
+	if e := []int{arg}; !reflect.DeepEqual(replySlice, e) {
+		t.Errorf("Slice: expected %v got %v", e, replySlice)
+	}
+
+	// Array
+	replyArray := [1]int{}
+	err = client.Call("BuiltinTypes.Array", arg, &replyArray)
+	if err != nil {
+		t.Errorf("Array: expected no error but got string %q", err.Error())
+	}
+	if e := [1]int{arg}; !reflect.DeepEqual(replyArray, e) {
+		t.Errorf("Array: expected %v got %v", e, replyArray)
+	}
+}
+
 func TestMalformedInput(t *testing.T) {
 	cli, srv := net.Pipe()
 	go cli.Write([]byte(`{id:1}`)) // invalid json
diff --git a/libgo/go/net/rpc/jsonrpc/client.go b/libgo/go/net/rpc/jsonrpc/client.go
index da1b816..e6359be 100644
--- a/libgo/go/net/rpc/jsonrpc/client.go
+++ b/libgo/go/net/rpc/jsonrpc/client.go
@@ -2,8 +2,9 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package jsonrpc implements a JSON-RPC ClientCodec and ServerCodec
+// Package jsonrpc implements a JSON-RPC 1.0 ClientCodec and ServerCodec
 // for the rpc package.
+// For JSON-RPC 2.0 support, see https://godoc.org/?q=json-rpc+2.0
 package jsonrpc
 
 import (
diff --git a/libgo/go/net/rpc/server.go b/libgo/go/net/rpc/server.go
index 18ea629..29aae7e 100644
--- a/libgo/go/net/rpc/server.go
+++ b/libgo/go/net/rpc/server.go
@@ -187,8 +187,7 @@
 
 // Server represents an RPC Server.
 type Server struct {
-	mu         sync.RWMutex // protects the serviceMap
-	serviceMap map[string]*service
+	serviceMap sync.Map   // map[string]*service
 	reqLock    sync.Mutex // protects freeReq
 	freeReq    *Request
 	respLock   sync.Mutex // protects freeResp
@@ -197,7 +196,7 @@
 
 // NewServer returns a new Server.
 func NewServer() *Server {
-	return &Server{serviceMap: make(map[string]*service)}
+	return &Server{}
 }
 
 // DefaultServer is the default instance of *Server.
@@ -240,11 +239,6 @@
 }
 
 func (server *Server) register(rcvr interface{}, name string, useName bool) error {
-	server.mu.Lock()
-	defer server.mu.Unlock()
-	if server.serviceMap == nil {
-		server.serviceMap = make(map[string]*service)
-	}
 	s := new(service)
 	s.typ = reflect.TypeOf(rcvr)
 	s.rcvr = reflect.ValueOf(rcvr)
@@ -262,9 +256,6 @@
 		log.Print(s)
 		return errors.New(s)
 	}
-	if _, present := server.serviceMap[sname]; present {
-		return errors.New("rpc: service already defined: " + sname)
-	}
 	s.name = sname
 
 	// Install the methods
@@ -283,7 +274,10 @@
 		log.Print(str)
 		return errors.New(str)
 	}
-	server.serviceMap[s.name] = s
+
+	if _, dup := server.serviceMap.LoadOrStore(sname, s); dup {
+		return errors.New("rpc: service already defined: " + sname)
+	}
 	return nil
 }
 
@@ -571,10 +565,17 @@
 	}
 
 	replyv = reflect.New(mtype.ReplyType.Elem())
+
+	switch mtype.ReplyType.Elem().Kind() {
+	case reflect.Map:
+		replyv.Elem().Set(reflect.MakeMap(mtype.ReplyType.Elem()))
+	case reflect.Slice:
+		replyv.Elem().Set(reflect.MakeSlice(mtype.ReplyType.Elem(), 0, 0))
+	}
 	return
 }
 
-func (server *Server) readRequestHeader(codec ServerCodec) (service *service, mtype *methodType, req *Request, keepReading bool, err error) {
+func (server *Server) readRequestHeader(codec ServerCodec) (svc *service, mtype *methodType, req *Request, keepReading bool, err error) {
 	// Grab the request header.
 	req = server.getRequest()
 	err = codec.ReadRequestHeader(req)
@@ -600,14 +601,13 @@
 	methodName := req.ServiceMethod[dot+1:]
 
 	// Look up the request.
-	server.mu.RLock()
-	service = server.serviceMap[serviceName]
-	server.mu.RUnlock()
-	if service == nil {
+	svci, ok := server.serviceMap.Load(serviceName)
+	if !ok {
 		err = errors.New("rpc: can't find service " + req.ServiceMethod)
 		return
 	}
-	mtype = service.method[methodName]
+	svc = svci.(*service)
+	mtype = svc.method[methodName]
 	if mtype == nil {
 		err = errors.New("rpc: can't find method " + req.ServiceMethod)
 	}
diff --git a/libgo/go/net/rpc/server_test.go b/libgo/go/net/rpc/server_test.go
index 8369c9d..fb97f82 100644
--- a/libgo/go/net/rpc/server_test.go
+++ b/libgo/go/net/rpc/server_test.go
@@ -11,6 +11,7 @@
 	"log"
 	"net"
 	"net/http/httptest"
+	"reflect"
 	"runtime"
 	"strings"
 	"sync"
@@ -85,6 +86,24 @@
 	hidden
 }
 
+type BuiltinTypes struct{}
+
+func (BuiltinTypes) Map(args *Args, reply *map[int]int) error {
+	(*reply)[args.A] = args.B
+	return nil
+}
+
+func (BuiltinTypes) Slice(args *Args, reply *[]int) error {
+	*reply = append(*reply, args.A, args.B)
+	return nil
+}
+
+func (BuiltinTypes) Array(args *Args, reply *[2]int) error {
+	(*reply)[0] = args.A
+	(*reply)[1] = args.B
+	return nil
+}
+
 func listenTCP() (net.Listener, string) {
 	l, e := net.Listen("tcp", "127.0.0.1:0") // any available address
 	if e != nil {
@@ -97,6 +116,7 @@
 	Register(new(Arith))
 	Register(new(Embed))
 	RegisterName("net.rpc.Arith", new(Arith))
+	Register(BuiltinTypes{})
 
 	var l net.Listener
 	l, serverAddr = listenTCP()
@@ -326,6 +346,49 @@
 	}
 }
 
+func TestBuiltinTypes(t *testing.T) {
+	once.Do(startServer)
+
+	client, err := DialHTTP("tcp", httpServerAddr)
+	if err != nil {
+		t.Fatal("dialing", err)
+	}
+	defer client.Close()
+
+	// Map
+	args := &Args{7, 8}
+	replyMap := map[int]int{}
+	err = client.Call("BuiltinTypes.Map", args, &replyMap)
+	if err != nil {
+		t.Errorf("Map: expected no error but got string %q", err.Error())
+	}
+	if replyMap[args.A] != args.B {
+		t.Errorf("Map: expected %d got %d", args.B, replyMap[args.A])
+	}
+
+	// Slice
+	args = &Args{7, 8}
+	replySlice := []int{}
+	err = client.Call("BuiltinTypes.Slice", args, &replySlice)
+	if err != nil {
+		t.Errorf("Slice: expected no error but got string %q", err.Error())
+	}
+	if e := []int{args.A, args.B}; !reflect.DeepEqual(replySlice, e) {
+		t.Errorf("Slice: expected %v got %v", e, replySlice)
+	}
+
+	// Array
+	args = &Args{7, 8}
+	replyArray := [2]int{}
+	err = client.Call("BuiltinTypes.Array", args, &replyArray)
+	if err != nil {
+		t.Errorf("Array: expected no error but got string %q", err.Error())
+	}
+	if e := [2]int{args.A, args.B}; !reflect.DeepEqual(replyArray, e) {
+		t.Errorf("Array: expected %v got %v", e, replyArray)
+	}
+}
+
 // CodecEmulator provides a client-like api and a ServerCodec interface.
 // Can be used to test ServeRequest.
 type CodecEmulator struct {
@@ -619,13 +682,13 @@
 
 // Tests the fix to issue 11221. Without the fix, this loops forever or crashes.
 func TestAcceptExitAfterListenerClose(t *testing.T) {
-	newServer = NewServer()
+	newServer := NewServer()
 	newServer.Register(new(Arith))
 	newServer.RegisterName("net.rpc.Arith", new(Arith))
 	newServer.RegisterName("newServer.Arith", new(Arith))
 
 	var l net.Listener
-	l, newServerAddr = listenTCP()
+	l, _ = listenTCP()
 	l.Close()
 	newServer.Accept(l)
 }
diff --git a/libgo/go/net/sendfile_bsd.go b/libgo/go/net/sendfile_bsd.go
new file mode 100644
index 0000000..7a2b48c
--- /dev/null
+++ b/libgo/go/net/sendfile_bsd.go
@@ -0,0 +1,67 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build dragonfly freebsd
+
+package net
+
+import (
+	"internal/poll"
+	"io"
+	"os"
+)
+
+// sendFile copies the contents of r to c using the sendfile
+// system call to minimize copies.
+//
+// if handled == true, sendFile returns the number of bytes copied and any
+// non-EOF error.
+//
+// if handled == false, sendFile performed no work.
+func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
+	// FreeBSD and DragonFly use 0 as the "until EOF" value.
+	// If you pass in more bytes than the file contains, it will
+	// loop back to the beginning ad nauseam until it's sent
+	// exactly the number of bytes told to. As such, we need to
+	// know exactly how many bytes to send.
+	var remain int64 = 0
+
+	lr, ok := r.(*io.LimitedReader)
+	if ok {
+		remain, r = lr.N, lr.R
+		if remain <= 0 {
+			return 0, nil, true
+		}
+	}
+	f, ok := r.(*os.File)
+	if !ok {
+		return 0, nil, false
+	}
+
+	if remain == 0 {
+		fi, err := f.Stat()
+		if err != nil {
+			return 0, err, false
+		}
+
+		remain = fi.Size()
+	}
+
+	// The other quirk with FreeBSD/DragonFly's sendfile
+	// implementation is that it doesn't use the current position
+	// of the file -- if you pass it offset 0, it starts from
+	// offset 0. There's no way to tell it "start from current
+	// position", so we have to manage that explicitly.
+	pos, err := f.Seek(0, io.SeekCurrent)
+	if err != nil {
+		return 0, err, false
+	}
+
+	written, err = poll.SendFile(&c.pfd, int(f.Fd()), pos, remain)
+
+	if lr != nil {
+		lr.N = remain - written
+	}
+	return written, wrapSyscallError("sendfile", err), written > 0
+}
diff --git a/libgo/go/net/sendfile_dragonfly.go b/libgo/go/net/sendfile_dragonfly.go
deleted file mode 100644
index d4b825c..0000000
--- a/libgo/go/net/sendfile_dragonfly.go
+++ /dev/null
@@ -1,106 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-	"io"
-	"os"
-	"syscall"
-)
-
-// maxSendfileSize is the largest chunk size we ask the kernel to copy
-// at a time.
-const maxSendfileSize int = 4 << 20
-
-// sendFile copies the contents of r to c using the sendfile
-// system call to minimize copies.
-//
-// if handled == true, sendFile returns the number of bytes copied and any
-// non-EOF error.
-//
-// if handled == false, sendFile performed no work.
-func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
-	// DragonFly uses 0 as the "until EOF" value. If you pass in more bytes than the
-	// file contains, it will loop back to the beginning ad nauseam until it's sent
-	// exactly the number of bytes told to. As such, we need to know exactly how many
-	// bytes to send.
-	var remain int64 = 0
-
-	lr, ok := r.(*io.LimitedReader)
-	if ok {
-		remain, r = lr.N, lr.R
-		if remain <= 0 {
-			return 0, nil, true
-		}
-	}
-	f, ok := r.(*os.File)
-	if !ok {
-		return 0, nil, false
-	}
-
-	if remain == 0 {
-		fi, err := f.Stat()
-		if err != nil {
-			return 0, err, false
-		}
-
-		remain = fi.Size()
-	}
-
-	// The other quirk with DragonFly's sendfile implementation is that it doesn't
-	// use the current position of the file -- if you pass it offset 0, it starts
-	// from offset 0. There's no way to tell it "start from current position", so
-	// we have to manage that explicitly.
-	pos, err := f.Seek(0, io.SeekCurrent)
-	if err != nil {
-		return 0, err, false
-	}
-
-	if err := c.writeLock(); err != nil {
-		return 0, err, true
-	}
-	defer c.writeUnlock()
-
-	dst := c.sysfd
-	src := int(f.Fd())
-	for remain > 0 {
-		n := maxSendfileSize
-		if int64(n) > remain {
-			n = int(remain)
-		}
-		pos1 := pos
-		n, err1 := syscall.Sendfile(dst, src, &pos1, n)
-		if n > 0 {
-			pos += int64(n)
-			written += int64(n)
-			remain -= int64(n)
-		}
-		if n == 0 && err1 == nil {
-			break
-		}
-		if err1 == syscall.EAGAIN {
-			if err1 = c.pd.waitWrite(); err1 == nil {
-				continue
-			}
-		}
-		if err1 == syscall.EINTR {
-			continue
-		}
-		if err1 != nil {
-			// This includes syscall.ENOSYS (no kernel
-			// support) and syscall.EINVAL (fd types which
-			// don't implement sendfile)
-			err = err1
-			break
-		}
-	}
-	if lr != nil {
-		lr.N = remain
-	}
-	if err != nil {
-		err = os.NewSyscallError("sendfile", err)
-	}
-	return written, err, written > 0
-}
diff --git a/libgo/go/net/sendfile_freebsd.go b/libgo/go/net/sendfile_freebsd.go
deleted file mode 100644
index 18cbb27..0000000
--- a/libgo/go/net/sendfile_freebsd.go
+++ /dev/null
@@ -1,106 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-	"io"
-	"os"
-	"syscall"
-)
-
-// maxSendfileSize is the largest chunk size we ask the kernel to copy
-// at a time.
-const maxSendfileSize int = 4 << 20
-
-// sendFile copies the contents of r to c using the sendfile
-// system call to minimize copies.
-//
-// if handled == true, sendFile returns the number of bytes copied and any
-// non-EOF error.
-//
-// if handled == false, sendFile performed no work.
-func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
-	// FreeBSD uses 0 as the "until EOF" value. If you pass in more bytes than the
-	// file contains, it will loop back to the beginning ad nauseam until it's sent
-	// exactly the number of bytes told to. As such, we need to know exactly how many
-	// bytes to send.
-	var remain int64 = 0
-
-	lr, ok := r.(*io.LimitedReader)
-	if ok {
-		remain, r = lr.N, lr.R
-		if remain <= 0 {
-			return 0, nil, true
-		}
-	}
-	f, ok := r.(*os.File)
-	if !ok {
-		return 0, nil, false
-	}
-
-	if remain == 0 {
-		fi, err := f.Stat()
-		if err != nil {
-			return 0, err, false
-		}
-
-		remain = fi.Size()
-	}
-
-	// The other quirk with FreeBSD's sendfile implementation is that it doesn't
-	// use the current position of the file -- if you pass it offset 0, it starts
-	// from offset 0. There's no way to tell it "start from current position", so
-	// we have to manage that explicitly.
-	pos, err := f.Seek(0, io.SeekCurrent)
-	if err != nil {
-		return 0, err, false
-	}
-
-	if err := c.writeLock(); err != nil {
-		return 0, err, true
-	}
-	defer c.writeUnlock()
-
-	dst := c.sysfd
-	src := int(f.Fd())
-	for remain > 0 {
-		n := maxSendfileSize
-		if int64(n) > remain {
-			n = int(remain)
-		}
-		pos1 := pos
-		n, err1 := syscall.Sendfile(dst, src, &pos1, n)
-		if n > 0 {
-			pos += int64(n)
-			written += int64(n)
-			remain -= int64(n)
-		}
-		if n == 0 && err1 == nil {
-			break
-		}
-		if err1 == syscall.EAGAIN {
-			if err1 = c.pd.waitWrite(); err1 == nil {
-				continue
-			}
-		}
-		if err1 == syscall.EINTR {
-			continue
-		}
-		if err1 != nil {
-			// This includes syscall.ENOSYS (no kernel
-			// support) and syscall.EINVAL (fd types which
-			// don't implement sendfile)
-			err = err1
-			break
-		}
-	}
-	if lr != nil {
-		lr.N = remain
-	}
-	if err != nil {
-		err = os.NewSyscallError("sendfile", err)
-	}
-	return written, err, written > 0
-}
diff --git a/libgo/go/net/sendfile_linux.go b/libgo/go/net/sendfile_linux.go
index 7e741f9..c537ea6 100644
--- a/libgo/go/net/sendfile_linux.go
+++ b/libgo/go/net/sendfile_linux.go
@@ -5,15 +5,11 @@
 package net
 
 import (
+	"internal/poll"
 	"io"
 	"os"
-	"syscall"
 )
 
-// maxSendfileSize is the largest chunk size we ask the kernel to copy
-// at a time.
-const maxSendfileSize int = 4 << 20
-
 // sendFile copies the contents of r to c using the sendfile
 // system call to minimize copies.
 //
@@ -36,44 +32,10 @@
 		return 0, nil, false
 	}
 
-	if err := c.writeLock(); err != nil {
-		return 0, err, true
-	}
-	defer c.writeUnlock()
+	written, err = poll.SendFile(&c.pfd, int(f.Fd()), remain)
 
-	dst := c.sysfd
-	src := int(f.Fd())
-	for remain > 0 {
-		n := maxSendfileSize
-		if int64(n) > remain {
-			n = int(remain)
-		}
-		n, err1 := syscall.Sendfile(dst, src, nil, n)
-		if n > 0 {
-			written += int64(n)
-			remain -= int64(n)
-		}
-		if n == 0 && err1 == nil {
-			break
-		}
-		if err1 == syscall.EAGAIN {
-			if err1 = c.pd.waitWrite(); err1 == nil {
-				continue
-			}
-		}
-		if err1 != nil {
-			// This includes syscall.ENOSYS (no kernel
-			// support) and syscall.EINVAL (fd types which
-			// don't implement sendfile)
-			err = err1
-			break
-		}
-	}
 	if lr != nil {
-		lr.N = remain
+		lr.N = remain - written
 	}
-	if err != nil {
-		err = os.NewSyscallError("sendfile", err)
-	}
-	return written, err, written > 0
+	return written, wrapSyscallError("sendfile", err), written > 0
 }
diff --git a/libgo/go/net/sendfile_solaris.go b/libgo/go/net/sendfile_solaris.go
index add70c3..63ca9d4 100644
--- a/libgo/go/net/sendfile_solaris.go
+++ b/libgo/go/net/sendfile_solaris.go
@@ -5,19 +5,11 @@
 package net
 
 import (
+	"internal/poll"
 	"io"
 	"os"
-	"syscall"
 )
 
-// Not strictly needed, but very helpful for debugging, see issue #10221.
-//go:cgo_import_dynamic _ _ "libsendfile.so"
-//go:cgo_import_dynamic _ _ "libsocket.so"
-
-// maxSendfileSize is the largest chunk size we ask the kernel to copy
-// at a time.
-const maxSendfileSize int = 4 << 20
-
 // sendFile copies the contents of r to c using the sendfile
 // system call to minimize copies.
 //
@@ -62,56 +54,10 @@
 		return 0, err, false
 	}
 
-	if err := c.writeLock(); err != nil {
-		return 0, err, true
-	}
-	defer c.writeUnlock()
+	written, err = poll.SendFile(&c.pfd, int(f.Fd()), pos, remain)
 
-	dst := c.sysfd
-	src := int(f.Fd())
-	for remain > 0 {
-		n := maxSendfileSize
-		if int64(n) > remain {
-			n = int(remain)
-		}
-		pos1 := pos
-		n, err1 := syscall.Sendfile(dst, src, &pos1, n)
-		if err1 == syscall.EAGAIN || err1 == syscall.EINTR {
-			// partial write may have occurred
-			if n = int(pos1 - pos); n == 0 {
-				// nothing more to write
-				err1 = nil
-			}
-		}
-		if n > 0 {
-			pos += int64(n)
-			written += int64(n)
-			remain -= int64(n)
-		}
-		if n == 0 && err1 == nil {
-			break
-		}
-		if err1 == syscall.EAGAIN {
-			if err1 = c.pd.waitWrite(); err1 == nil {
-				continue
-			}
-		}
-		if err1 == syscall.EINTR {
-			continue
-		}
-		if err1 != nil {
-			// This includes syscall.ENOSYS (no kernel
-			// support) and syscall.EINVAL (fd types which
-			// don't implement sendfile)
-			err = err1
-			break
-		}
-	}
 	if lr != nil {
-		lr.N = remain
+		lr.N = remain - written
 	}
-	if err != nil {
-		err = os.NewSyscallError("sendfile", err)
-	}
-	return written, err, written > 0
+	return written, wrapSyscallError("sendfile", err), written > 0
 }
diff --git a/libgo/go/net/sendfile_windows.go b/libgo/go/net/sendfile_windows.go
index bc0b7fb..bccd8b1 100644
--- a/libgo/go/net/sendfile_windows.go
+++ b/libgo/go/net/sendfile_windows.go
@@ -5,6 +5,7 @@
 package net
 
 import (
+	"internal/poll"
 	"io"
 	"os"
 	"syscall"
@@ -34,19 +35,10 @@
 		return 0, nil, false
 	}
 
-	if err := fd.writeLock(); err != nil {
-		return 0, err, true
-	}
-	defer fd.writeUnlock()
+	done, err := poll.SendFile(&fd.pfd, syscall.Handle(f.Fd()), n)
 
-	o := &fd.wop
-	o.qty = uint32(n)
-	o.handle = syscall.Handle(f.Fd())
-	done, err := wsrv.ExecIO(o, "TransmitFile", func(o *operation) error {
-		return syscall.TransmitFile(o.fd.sysfd, o.handle, o.qty, 0, &o.o, nil, syscall.TF_WRITE_BEHIND)
-	})
 	if err != nil {
-		return 0, os.NewSyscallError("transmitfile", err), false
+		return 0, wrapSyscallError("transmitfile", err), false
 	}
 	if lr != nil {
 		lr.N -= int64(done)
diff --git a/libgo/go/net/smtp/smtp.go b/libgo/go/net/smtp/smtp.go
index a408fa5..28472e4 100644
--- a/libgo/go/net/smtp/smtp.go
+++ b/libgo/go/net/smtp/smtp.go
@@ -298,7 +298,7 @@
 // messages is accomplished by including an email address in the to
 // parameter but not including it in the msg headers.
 //
-// The SendMail function and the the net/smtp package are low-level
+// The SendMail function and the net/smtp package are low-level
 // mechanisms and provide no support for DKIM signing, MIME
 // attachments (see the mime/multipart package), or other mail
 // functionality. Higher-level packages exist outside of the standard
diff --git a/libgo/go/net/smtp/smtp_test.go b/libgo/go/net/smtp/smtp_test.go
index c48fae6..9dbe3eb 100644
--- a/libgo/go/net/smtp/smtp_test.go
+++ b/libgo/go/net/smtp/smtp_test.go
@@ -9,9 +9,11 @@
 	"bytes"
 	"crypto/tls"
 	"crypto/x509"
+	"internal/testenv"
 	"io"
 	"net"
 	"net/textproto"
+	"runtime"
 	"strings"
 	"testing"
 	"time"
@@ -592,6 +594,9 @@
 `
 
 func TestTLSClient(t *testing.T) {
+	if runtime.GOOS == "freebsd" && runtime.GOARCH == "amd64" {
+		testenv.SkipFlaky(t, 19229)
+	}
 	ln := newLocalListener(t)
 	defer ln.Close()
 	errc := make(chan error)
diff --git a/libgo/go/net/sock_cloexec.go b/libgo/go/net/sock_cloexec.go
index 616a101..06ff10d 100644
--- a/libgo/go/net/sock_cloexec.go
+++ b/libgo/go/net/sock_cloexec.go
@@ -5,11 +5,12 @@
 // This file implements sysSocket and accept for platforms that
 // provide a fast path for setting SetNonblock and CloseOnExec.
 
-// +build freebsd linux
+// +build dragonfly freebsd linux
 
 package net
 
 import (
+	"internal/poll"
 	"os"
 	"syscall"
 )
@@ -42,46 +43,8 @@
 		return -1, os.NewSyscallError("socket", err)
 	}
 	if err = syscall.SetNonblock(s, true); err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return -1, os.NewSyscallError("setnonblock", err)
 	}
 	return s, nil
 }
-
-// Wrapper around the accept system call that marks the returned file
-// descriptor as nonblocking and close-on-exec.
-func accept(s int) (int, syscall.Sockaddr, error) {
-	ns, sa, err := accept4Func(s, syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC)
-	// On Linux the accept4 system call was introduced in 2.6.28
-	// kernel and on FreeBSD it was introduced in 10 kernel. If we
-	// get an ENOSYS error on both Linux and FreeBSD, or EINVAL
-	// error on Linux, fall back to using accept.
-	switch err {
-	case nil:
-		return ns, sa, nil
-	default: // errors other than the ones listed
-		return -1, sa, os.NewSyscallError("accept4", err)
-	case syscall.ENOSYS: // syscall missing
-	case syscall.EINVAL: // some Linux use this instead of ENOSYS
-	case syscall.EACCES: // some Linux use this instead of ENOSYS
-	case syscall.EFAULT: // some Linux use this instead of ENOSYS
-	}
-
-	// See ../syscall/exec_unix.go for description of ForkLock.
-	// It is probably okay to hold the lock across syscall.Accept
-	// because we have put fd.sysfd into non-blocking mode.
-	// However, a call to the File method will put it back into
-	// blocking mode. We can't take that risk, so no use of ForkLock here.
-	ns, sa, err = acceptFunc(s)
-	if err == nil {
-		syscall.CloseOnExec(ns)
-	}
-	if err != nil {
-		return -1, nil, os.NewSyscallError("accept", err)
-	}
-	if err = syscall.SetNonblock(ns, true); err != nil {
-		closeFunc(ns)
-		return -1, nil, os.NewSyscallError("setnonblock", err)
-	}
-	return ns, sa, nil
-}
diff --git a/libgo/go/net/sock_posix.go b/libgo/go/net/sock_posix.go
index 6bbfd12..a30efe2 100644
--- a/libgo/go/net/sock_posix.go
+++ b/libgo/go/net/sock_posix.go
@@ -8,6 +8,7 @@
 
 import (
 	"context"
+	"internal/poll"
 	"os"
 	"syscall"
 )
@@ -43,11 +44,11 @@
 		return nil, err
 	}
 	if err = setDefaultSockopts(s, family, sotype, ipv6only); err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return nil, err
 	}
 	if fd, err = newFD(s, family, sotype, net); err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return nil, err
 	}
 
@@ -127,17 +128,18 @@
 		if lsa, err = laddr.sockaddr(fd.family); err != nil {
 			return err
 		} else if lsa != nil {
-			if err := syscall.Bind(fd.sysfd, lsa); err != nil {
+			if err := syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
 				return os.NewSyscallError("bind", err)
 			}
 		}
 	}
-	var rsa syscall.Sockaddr
+	var rsa syscall.Sockaddr  // remote address from the user
+	var crsa syscall.Sockaddr // remote address we actually connected to
 	if raddr != nil {
 		if rsa, err = raddr.sockaddr(fd.family); err != nil {
 			return err
 		}
-		if err := fd.connect(ctx, lsa, rsa); err != nil {
+		if crsa, err = fd.connect(ctx, lsa, rsa); err != nil {
 			return err
 		}
 		fd.isConnected = true
@@ -146,8 +148,16 @@
 			return err
 		}
 	}
-	lsa, _ = syscall.Getsockname(fd.sysfd)
-	if rsa, _ = syscall.Getpeername(fd.sysfd); rsa != nil {
+	// Record the local and remote addresses from the actual socket.
+	// Get the local address by calling Getsockname.
+	// For the remote address, use
+	// 1) the one returned by the connect method, if any; or
+	// 2) the one from Getpeername, if it succeeds; or
+	// 3) the one passed to us as the raddr parameter.
+	lsa, _ = syscall.Getsockname(fd.pfd.Sysfd)
+	if crsa != nil {
+		fd.setAddr(fd.addrFunc()(lsa), fd.addrFunc()(crsa))
+	} else if rsa, _ = syscall.Getpeername(fd.pfd.Sysfd); rsa != nil {
 		fd.setAddr(fd.addrFunc()(lsa), fd.addrFunc()(rsa))
 	} else {
 		fd.setAddr(fd.addrFunc()(lsa), raddr)
@@ -156,23 +166,23 @@
 }
 
 func (fd *netFD) listenStream(laddr sockaddr, backlog int) error {
-	if err := setDefaultListenerSockopts(fd.sysfd); err != nil {
+	if err := setDefaultListenerSockopts(fd.pfd.Sysfd); err != nil {
 		return err
 	}
 	if lsa, err := laddr.sockaddr(fd.family); err != nil {
 		return err
 	} else if lsa != nil {
-		if err := syscall.Bind(fd.sysfd, lsa); err != nil {
+		if err := syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
 			return os.NewSyscallError("bind", err)
 		}
 	}
-	if err := listenFunc(fd.sysfd, backlog); err != nil {
+	if err := listenFunc(fd.pfd.Sysfd, backlog); err != nil {
 		return os.NewSyscallError("listen", err)
 	}
 	if err := fd.init(); err != nil {
 		return err
 	}
-	lsa, _ := syscall.Getsockname(fd.sysfd)
+	lsa, _ := syscall.Getsockname(fd.pfd.Sysfd)
 	fd.setAddr(fd.addrFunc()(lsa), nil)
 	return nil
 }
@@ -188,7 +198,7 @@
 		// multiple UDP listeners that listen on the same UDP
 		// port to join the same group address.
 		if addr.IP != nil && addr.IP.IsMulticast() {
-			if err := setDefaultMulticastSockopts(fd.sysfd); err != nil {
+			if err := setDefaultMulticastSockopts(fd.pfd.Sysfd); err != nil {
 				return err
 			}
 			addr := *addr
@@ -204,14 +214,14 @@
 	if lsa, err := laddr.sockaddr(fd.family); err != nil {
 		return err
 	} else if lsa != nil {
-		if err := syscall.Bind(fd.sysfd, lsa); err != nil {
+		if err := syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
 			return os.NewSyscallError("bind", err)
 		}
 	}
 	if err := fd.init(); err != nil {
 		return err
 	}
-	lsa, _ := syscall.Getsockname(fd.sysfd)
+	lsa, _ := syscall.Getsockname(fd.pfd.Sysfd)
 	fd.setAddr(fd.addrFunc()(lsa), nil)
 	return nil
 }
diff --git a/libgo/go/net/sockopt_bsd.go b/libgo/go/net/sockopt_bsd.go
index 734a109..1aae88a 100644
--- a/libgo/go/net/sockopt_bsd.go
+++ b/libgo/go/net/sockopt_bsd.go
@@ -25,7 +25,7 @@
 			syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_PORTRANGE, syscall.IPV6_PORTRANGE_HIGH)
 		}
 	}
-	if supportsIPv4map && family == syscall.AF_INET6 && sotype != syscall.SOCK_RAW {
+	if supportsIPv4map() && family == syscall.AF_INET6 && sotype != syscall.SOCK_RAW {
 		// Allow both IP versions even if the OS default
 		// is otherwise. Note that some operating systems
 		// never admit this option.
diff --git a/libgo/go/net/sockopt_posix.go b/libgo/go/net/sockopt_posix.go
index cacd048..29edddb 100644
--- a/libgo/go/net/sockopt_posix.go
+++ b/libgo/go/net/sockopt_posix.go
@@ -7,7 +7,7 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 )
 
@@ -101,27 +101,21 @@
 }
 
 func setReadBuffer(fd *netFD, bytes int) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.SOL_SOCKET, syscall.SO_RCVBUF, bytes))
+	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_RCVBUF, bytes)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setWriteBuffer(fd *netFD, bytes int) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.SOL_SOCKET, syscall.SO_SNDBUF, bytes))
+	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_SNDBUF, bytes)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setKeepAlive(fd *netFD, keepalive bool) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.SOL_SOCKET, syscall.SO_KEEPALIVE, boolint(keepalive)))
+	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_KEEPALIVE, boolint(keepalive))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setLinger(fd *netFD, sec int) error {
@@ -133,9 +127,7 @@
 		l.Onoff = 0
 		l.Linger = 0
 	}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptLinger(fd.sysfd, syscall.SOL_SOCKET, syscall.SO_LINGER, &l))
+	err := fd.pfd.SetsockoptLinger(syscall.SOL_SOCKET, syscall.SO_LINGER, &l)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/sockoptip_bsd.go b/libgo/go/net/sockoptip_bsd.go
index b15c639..b11f3a4 100644
--- a/libgo/go/net/sockoptip_bsd.go
+++ b/libgo/go/net/sockoptip_bsd.go
@@ -7,28 +7,24 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 )
 
 func setIPv4MulticastInterface(fd *netFD, ifi *Interface) error {
 	ip, err := interfaceToIPv4Addr(ifi)
 	if err != nil {
-		return os.NewSyscallError("setsockopt", err)
+		return wrapSyscallError("setsockopt", err)
 	}
 	var a [4]byte
 	copy(a[:], ip.To4())
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInet4Addr(fd.sysfd, syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, a))
+	err = fd.pfd.SetsockoptInet4Addr(syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, a)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setIPv4MulticastLoopback(fd *netFD, v bool) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptByte(fd.sysfd, syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, byte(boolint(v))))
+	err := fd.pfd.SetsockoptByte(syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, byte(boolint(v)))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/sockoptip_linux.go b/libgo/go/net/sockoptip_linux.go
index c1dcc91..bd7d834 100644
--- a/libgo/go/net/sockoptip_linux.go
+++ b/libgo/go/net/sockoptip_linux.go
@@ -5,7 +5,7 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 )
 
@@ -15,17 +15,13 @@
 		v = int32(ifi.Index)
 	}
 	mreq := &syscall.IPMreqn{Ifindex: v}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreqn(fd.sysfd, syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, mreq))
+	err := fd.pfd.SetsockoptIPMreqn(syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, mreq)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setIPv4MulticastLoopback(fd *netFD, v bool) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, boolint(v)))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, boolint(v))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/sockoptip_posix.go b/libgo/go/net/sockoptip_posix.go
index 4afd4c8..92af764 100644
--- a/libgo/go/net/sockoptip_posix.go
+++ b/libgo/go/net/sockoptip_posix.go
@@ -7,7 +7,7 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 )
 
@@ -16,11 +16,9 @@
 	if err := setIPv4MreqToInterface(mreq, ifi); err != nil {
 		return err
 	}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreq(fd.sysfd, syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq))
+	err := fd.pfd.SetsockoptIPMreq(syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setIPv6MulticastInterface(fd *netFD, ifi *Interface) error {
@@ -28,19 +26,15 @@
 	if ifi != nil {
 		v = ifi.Index
 	}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_IF, v))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_IF, v)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setIPv6MulticastLoopback(fd *netFD, v bool) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_LOOP, boolint(v)))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_LOOP, boolint(v))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func joinIPv6Group(fd *netFD, ifi *Interface, ip IP) error {
@@ -49,9 +43,7 @@
 	if ifi != nil {
 		mreq.Interface = uint32(ifi.Index)
 	}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptIPv6Mreq(fd.sysfd, syscall.IPPROTO_IPV6, syscall.IPV6_JOIN_GROUP, mreq))
+	err := fd.pfd.SetsockoptIPv6Mreq(syscall.IPPROTO_IPV6, syscall.IPV6_JOIN_GROUP, mreq)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/sockoptip_windows.go b/libgo/go/net/sockoptip_windows.go
index 916debe..6267603 100644
--- a/libgo/go/net/sockoptip_windows.go
+++ b/libgo/go/net/sockoptip_windows.go
@@ -6,6 +6,7 @@
 
 import (
 	"os"
+	"runtime"
 	"syscall"
 	"unsafe"
 )
@@ -17,17 +18,13 @@
 	}
 	var a [4]byte
 	copy(a[:], ip.To4())
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.Setsockopt(fd.sysfd, syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, (*byte)(unsafe.Pointer(&a[0])), 4))
+	err = fd.pfd.Setsockopt(syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, (*byte)(unsafe.Pointer(&a[0])), 4)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
 
 func setIPv4MulticastLoopback(fd *netFD, v bool) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, boolint(v)))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, boolint(v))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/sys_cloexec.go b/libgo/go/net/sys_cloexec.go
index f2ea842..def05cb 100644
--- a/libgo/go/net/sys_cloexec.go
+++ b/libgo/go/net/sys_cloexec.go
@@ -5,11 +5,12 @@
 // This file implements sysSocket and accept for platforms that do not
 // provide a fast path for setting SetNonblock and CloseOnExec.
 
-// +build aix darwin dragonfly nacl netbsd openbsd solaris
+// +build aix darwin nacl netbsd openbsd solaris
 
 package net
 
 import (
+	"internal/poll"
 	"os"
 	"syscall"
 )
@@ -28,30 +29,8 @@
 		return -1, os.NewSyscallError("socket", err)
 	}
 	if err = syscall.SetNonblock(s, true); err != nil {
-		closeFunc(s)
+		poll.CloseFunc(s)
 		return -1, os.NewSyscallError("setnonblock", err)
 	}
 	return s, nil
 }
-
-// Wrapper around the accept system call that marks the returned file
-// descriptor as nonblocking and close-on-exec.
-func accept(s int) (int, syscall.Sockaddr, error) {
-	// See ../syscall/exec_unix.go for description of ForkLock.
-	// It is probably okay to hold the lock across syscall.Accept
-	// because we have put fd.sysfd into non-blocking mode.
-	// However, a call to the File method will put it back into
-	// blocking mode. We can't take that risk, so no use of ForkLock here.
-	ns, sa, err := acceptFunc(s)
-	if err == nil {
-		syscall.CloseOnExec(ns)
-	}
-	if err != nil {
-		return -1, nil, os.NewSyscallError("accept", err)
-	}
-	if err = syscall.SetNonblock(ns, true); err != nil {
-		closeFunc(ns)
-		return -1, nil, os.NewSyscallError("setnonblock", err)
-	}
-	return ns, sa, nil
-}
diff --git a/libgo/go/net/tcpsock.go b/libgo/go/net/tcpsock.go
index 69731eb..e957aa3 100644
--- a/libgo/go/net/tcpsock.go
+++ b/libgo/go/net/tcpsock.go
@@ -50,28 +50,34 @@
 	return a
 }
 
-// ResolveTCPAddr parses addr as a TCP address of the form "host:port"
-// or "[ipv6-host%zone]:port" and resolves a pair of domain name and
-// port name on the network net, which must be "tcp", "tcp4" or
-// "tcp6".  A literal address or host name for IPv6 must be enclosed
-// in square brackets, as in "[::1]:80", "[ipv6-host]:http" or
-// "[ipv6-host%zone]:80".
+// ResolveTCPAddr returns an address of TCP end point.
 //
-// Resolving a hostname is not recommended because this returns at most
-// one of its IP addresses.
-func ResolveTCPAddr(net, addr string) (*TCPAddr, error) {
-	switch net {
+// The network must be a TCP network name.
+//
+// If the host in the address parameter is not a literal IP address or
+// the port is not a literal port number, ResolveTCPAddr resolves the
+// address to an address of TCP end point.
+// Otherwise, it parses the address as a pair of literal IP address
+// and port number.
+// The address parameter can use a host name, but this is not
+// recommended, because it will return at most one of the host name's
+// IP addresses.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func ResolveTCPAddr(network, address string) (*TCPAddr, error) {
+	switch network {
 	case "tcp", "tcp4", "tcp6":
 	case "": // a hint wildcard for Go 1.0 undocumented behavior
-		net = "tcp"
+		network = "tcp"
 	default:
-		return nil, UnknownNetworkError(net)
+		return nil, UnknownNetworkError(network)
 	}
-	addrs, err := DefaultResolver.internetAddrList(context.Background(), net, addr)
+	addrs, err := DefaultResolver.internetAddrList(context.Background(), network, address)
 	if err != nil {
 		return nil, err
 	}
-	return addrs.first(isIPv4).(*TCPAddr), nil
+	return addrs.forResolve(network, address).(*TCPAddr), nil
 }
 
 // TCPConn is an implementation of the Conn interface for TCP network
@@ -80,6 +86,15 @@
 	conn
 }
 
+// SyscallConn returns a raw network connection.
+// This implements the syscall.Conn interface.
+func (c *TCPConn) SyscallConn() (syscall.RawConn, error) {
+	if !c.ok() {
+		return nil, syscall.EINVAL
+	}
+	return newRawConn(c.fd)
+}
+
 // ReadFrom implements the io.ReaderFrom ReadFrom method.
 func (c *TCPConn) ReadFrom(r io.Reader) (int64, error) {
 	if !c.ok() {
@@ -181,21 +196,25 @@
 	return c
 }
 
-// DialTCP connects to the remote address raddr on the network net,
-// which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is
-// used as the local address for the connection.
-func DialTCP(net string, laddr, raddr *TCPAddr) (*TCPConn, error) {
-	switch net {
+// DialTCP acts like Dial for TCP networks.
+//
+// The network must be a TCP network name; see func Dial for details.
+//
+// If laddr is nil, a local address is automatically chosen.
+// If the IP field of raddr is nil or an unspecified IP address, the
+// local system is assumed.
+func DialTCP(network string, laddr, raddr *TCPAddr) (*TCPConn, error) {
+	switch network {
 	case "tcp", "tcp4", "tcp6":
 	default:
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(net)}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(network)}
 	}
 	if raddr == nil {
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
 	}
-	c, err := dialTCP(context.Background(), net, laddr, raddr)
+	c, err := dialTCP(context.Background(), network, laddr, raddr)
 	if err != nil {
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
 	}
 	return c, nil
 }
@@ -255,7 +274,7 @@
 	if !l.ok() {
 		return syscall.EINVAL
 	}
-	if err := l.fd.setDeadline(t); err != nil {
+	if err := l.fd.pfd.SetDeadline(t); err != nil {
 		return &OpError{Op: "set", Net: l.fd.net, Source: nil, Addr: l.fd.laddr, Err: err}
 	}
 	return nil
@@ -279,22 +298,27 @@
 	return
 }
 
-// ListenTCP announces on the TCP address laddr and returns a TCP
-// listener. Net must be "tcp", "tcp4", or "tcp6".  If laddr has a
-// port of 0, ListenTCP will choose an available port. The caller can
-// use the Addr method of TCPListener to retrieve the chosen address.
-func ListenTCP(net string, laddr *TCPAddr) (*TCPListener, error) {
-	switch net {
+// ListenTCP acts like Listen for TCP networks.
+//
+// The network must be a TCP network name; see func Dial for details.
+//
+// If the IP field of laddr is nil or an unspecified IP address,
+// ListenTCP listens on all available unicast and anycast IP addresses
+// of the local system.
+// If the Port field of laddr is 0, a port number is automatically
+// chosen.
+func ListenTCP(network string, laddr *TCPAddr) (*TCPListener, error) {
+	switch network {
 	case "tcp", "tcp4", "tcp6":
 	default:
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(net)}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(network)}
 	}
 	if laddr == nil {
 		laddr = &TCPAddr{}
 	}
-	ln, err := listenTCP(context.Background(), net, laddr)
+	ln, err := listenTCP(context.Background(), network, laddr)
 	if err != nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
 	}
 	return ln, nil
 }
diff --git a/libgo/go/net/tcpsock_plan9.go b/libgo/go/net/tcpsock_plan9.go
index d286060..e37f065 100644
--- a/libgo/go/net/tcpsock_plan9.go
+++ b/libgo/go/net/tcpsock_plan9.go
@@ -48,6 +48,9 @@
 }
 
 func (ln *TCPListener) close() error {
+	if err := ln.fd.pfd.Close(); err != nil {
+		return err
+	}
 	if _, err := ln.fd.ctl.WriteString("hangup"); err != nil {
 		ln.fd.ctl.Close()
 		return err
diff --git a/libgo/go/net/tcpsock_posix.go b/libgo/go/net/tcpsock_posix.go
index 7533c24..9ba199d 100644
--- a/libgo/go/net/tcpsock_posix.go
+++ b/libgo/go/net/tcpsock_posix.go
@@ -18,7 +18,7 @@
 	case *syscall.SockaddrInet4:
 		return &TCPAddr{IP: sa.Addr[0:], Port: sa.Port}
 	case *syscall.SockaddrInet6:
-		return &TCPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneToString(int(sa.ZoneId))}
+		return &TCPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
 	}
 	return nil
 }
diff --git a/libgo/go/net/tcpsock_test.go b/libgo/go/net/tcpsock_test.go
index 5115422..660f424 100644
--- a/libgo/go/net/tcpsock_test.go
+++ b/libgo/go/net/tcpsock_test.go
@@ -32,28 +32,28 @@
 }
 
 func BenchmarkTCP6OneShot(b *testing.B) {
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		b.Skip("ipv6 is not supported")
 	}
 	benchmarkTCP(b, false, false, "[::1]:0")
 }
 
 func BenchmarkTCP6OneShotTimeout(b *testing.B) {
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		b.Skip("ipv6 is not supported")
 	}
 	benchmarkTCP(b, false, true, "[::1]:0")
 }
 
 func BenchmarkTCP6Persistent(b *testing.B) {
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		b.Skip("ipv6 is not supported")
 	}
 	benchmarkTCP(b, true, false, "[::1]:0")
 }
 
 func BenchmarkTCP6PersistentTimeout(b *testing.B) {
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		b.Skip("ipv6 is not supported")
 	}
 	benchmarkTCP(b, true, true, "[::1]:0")
@@ -163,7 +163,7 @@
 }
 
 func BenchmarkTCP6ConcurrentReadWrite(b *testing.B) {
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		b.Skip("ipv6 is not supported")
 	}
 	benchmarkTCPConcurrentReadWrite(b, "[::1]:0")
@@ -372,7 +372,7 @@
 func TestIPv6LinkLocalUnicastTCP(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		t.Skip("IPv6 is not supported")
 	}
 
diff --git a/libgo/go/net/tcpsock_unix_test.go b/libgo/go/net/tcpsock_unix_test.go
index 2375fe2..3af1834 100644
--- a/libgo/go/net/tcpsock_unix_test.go
+++ b/libgo/go/net/tcpsock_unix_test.go
@@ -2,11 +2,14 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin
+// +build !plan9,!windows
 
 package net
 
 import (
+	"context"
+	"internal/testenv"
+	"math/rand"
 	"runtime"
 	"sync"
 	"syscall"
@@ -77,3 +80,37 @@
 	ln.Close()
 	wg.Wait()
 }
+
+// Issue 19289.
+// Test that a canceled Dial does not cause a subsequent Dial to succeed.
+func TestTCPSpuriousConnSetupCompletionWithCancel(t *testing.T) {
+	if testenv.Builder() == "" {
+		testenv.MustHaveExternalNetwork(t)
+	}
+	t.Parallel()
+	const tries = 10000
+	var wg sync.WaitGroup
+	wg.Add(tries * 2)
+	sem := make(chan bool, 5)
+	for i := 0; i < tries; i++ {
+		sem <- true
+		ctx, cancel := context.WithCancel(context.Background())
+		go func() {
+			defer wg.Done()
+			time.Sleep(time.Duration(rand.Int63n(int64(5 * time.Millisecond))))
+			cancel()
+		}()
+		go func(i int) {
+			defer wg.Done()
+			var dialer Dialer
+			// Try to connect to a real host on a port
+			// that it is not listening on.
+			_, err := dialer.DialContext(ctx, "tcp", "golang.org:3")
+			if err == nil {
+				t.Errorf("Dial to unbound port succeeded on attempt %d", i)
+			}
+			<-sem
+		}(i)
+	}
+	wg.Wait()
+}
diff --git a/libgo/go/net/tcpsockopt_darwin.go b/libgo/go/net/tcpsockopt_darwin.go
index 0d1310e..7415c76 100644
--- a/libgo/go/net/tcpsockopt_darwin.go
+++ b/libgo/go/net/tcpsockopt_darwin.go
@@ -5,7 +5,7 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 	"time"
 )
@@ -13,17 +13,15 @@
 const sysTCP_KEEPINTVL = 0x101
 
 func setKeepAlivePeriod(fd *netFD, d time.Duration) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
 	// The kernel expects seconds so round to next highest second.
 	d += (time.Second - time.Nanosecond)
 	secs := int(d.Seconds())
-	switch err := syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, sysTCP_KEEPINTVL, secs); err {
+	switch err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, sysTCP_KEEPINTVL, secs); err {
 	case nil, syscall.ENOPROTOOPT: // OS X 10.7 and earlier don't support this option
 	default:
-		return os.NewSyscallError("setsockopt", err)
+		return wrapSyscallError("setsockopt", err)
 	}
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, syscall.TCP_KEEPALIVE, secs))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_KEEPALIVE, secs)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/tcpsockopt_dragonfly.go b/libgo/go/net/tcpsockopt_dragonfly.go
index 7cc716b..2b018f2 100644
--- a/libgo/go/net/tcpsockopt_dragonfly.go
+++ b/libgo/go/net/tcpsockopt_dragonfly.go
@@ -5,22 +5,20 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 	"time"
 )
 
 func setKeepAlivePeriod(fd *netFD, d time.Duration) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
 	// The kernel expects milliseconds so round to next highest
 	// millisecond.
 	d += (time.Millisecond - time.Nanosecond)
 	msecs := int(d / time.Millisecond)
-	if err := syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, syscall.TCP_KEEPINTVL, msecs); err != nil {
-		return os.NewSyscallError("setsockopt", err)
+	if err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_KEEPINTVL, msecs); err != nil {
+		return wrapSyscallError("setsockopt", err)
 	}
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, syscall.TCP_KEEPIDLE, msecs))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_KEEPIDLE, msecs)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/tcpsockopt_posix.go b/libgo/go/net/tcpsockopt_posix.go
index 36866ac..5e00ba1 100644
--- a/libgo/go/net/tcpsockopt_posix.go
+++ b/libgo/go/net/tcpsockopt_posix.go
@@ -7,14 +7,12 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 )
 
 func setNoDelay(fd *netFD, noDelay bool) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, syscall.TCP_NODELAY, boolint(noDelay)))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_NODELAY, boolint(noDelay))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/tcpsockopt_solaris.go b/libgo/go/net/tcpsockopt_solaris.go
index 347c17d..aa86a29 100644
--- a/libgo/go/net/tcpsockopt_solaris.go
+++ b/libgo/go/net/tcpsockopt_solaris.go
@@ -2,26 +2,20 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// TCP socket options for solaris
-
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 	"time"
 )
 
-// Set keep alive period.
 func setKeepAlivePeriod(fd *netFD, d time.Duration) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-
 	// The kernel expects seconds so round to next highest second.
 	d += (time.Second - time.Nanosecond)
 	secs := int(d.Seconds())
 
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, syscall.SO_KEEPALIVE, secs))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.SO_KEEPALIVE, secs)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/tcpsockopt_unix.go b/libgo/go/net/tcpsockopt_unix.go
index 46e5e6d..d589258 100644
--- a/libgo/go/net/tcpsockopt_unix.go
+++ b/libgo/go/net/tcpsockopt_unix.go
@@ -7,21 +7,19 @@
 package net
 
 import (
-	"os"
+	"runtime"
 	"syscall"
 	"time"
 )
 
 func setKeepAlivePeriod(fd *netFD, d time.Duration) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
 	// The kernel expects seconds so round to next highest second.
 	d += (time.Second - time.Nanosecond)
 	secs := int(d.Seconds())
-	if err := syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, syscall.TCP_KEEPINTVL, secs); err != nil {
-		return os.NewSyscallError("setsockopt", err)
+	if err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_KEEPINTVL, secs); err != nil {
+		return wrapSyscallError("setsockopt", err)
 	}
-	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd.sysfd, syscall.IPPROTO_TCP, syscall.TCP_KEEPIDLE, secs))
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_KEEPIDLE, secs)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
 }
diff --git a/libgo/go/net/tcpsockopt_windows.go b/libgo/go/net/tcpsockopt_windows.go
index 45a4dca..73dead1 100644
--- a/libgo/go/net/tcpsockopt_windows.go
+++ b/libgo/go/net/tcpsockopt_windows.go
@@ -6,16 +6,13 @@
 
 import (
 	"os"
+	"runtime"
 	"syscall"
 	"time"
 	"unsafe"
 )
 
 func setKeepAlivePeriod(fd *netFD, d time.Duration) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
 	// The kernel expects milliseconds so round to next highest
 	// millisecond.
 	d += (time.Millisecond - time.Nanosecond)
@@ -27,6 +24,7 @@
 	}
 	ret := uint32(0)
 	size := uint32(unsafe.Sizeof(ka))
-	err := syscall.WSAIoctl(fd.sysfd, syscall.SIO_KEEPALIVE_VALS, (*byte)(unsafe.Pointer(&ka)), size, nil, 0, &ret, nil, 0)
+	err := fd.pfd.WSAIoctl(syscall.SIO_KEEPALIVE_VALS, (*byte)(unsafe.Pointer(&ka)), size, nil, 0, &ret, nil, 0)
+	runtime.KeepAlive(fd)
 	return os.NewSyscallError("wsaioctl", err)
 }
diff --git a/libgo/go/net/timeout_test.go b/libgo/go/net/timeout_test.go
index 55bbf44..9de7801 100644
--- a/libgo/go/net/timeout_test.go
+++ b/libgo/go/net/timeout_test.go
@@ -6,6 +6,7 @@
 
 import (
 	"fmt"
+	"internal/poll"
 	"internal/testenv"
 	"io"
 	"io/ioutil"
@@ -145,9 +146,9 @@
 }{
 	// Tests that accept deadlines in the past work, even if
 	// there's incoming connections available.
-	{-5 * time.Second, [2]error{errTimeout, errTimeout}},
+	{-5 * time.Second, [2]error{poll.ErrTimeout, poll.ErrTimeout}},
 
-	{50 * time.Millisecond, [2]error{nil, errTimeout}},
+	{50 * time.Millisecond, [2]error{nil, poll.ErrTimeout}},
 }
 
 func TestAcceptTimeout(t *testing.T) {
@@ -299,9 +300,9 @@
 }{
 	// Tests that read deadlines work, even if there's data ready
 	// to be read.
-	{-5 * time.Second, [2]error{errTimeout, errTimeout}},
+	{-5 * time.Second, [2]error{poll.ErrTimeout, poll.ErrTimeout}},
 
-	{50 * time.Millisecond, [2]error{nil, errTimeout}},
+	{50 * time.Millisecond, [2]error{nil, poll.ErrTimeout}},
 }
 
 func TestReadTimeout(t *testing.T) {
@@ -423,9 +424,9 @@
 }{
 	// Tests that read deadlines work, even if there's data ready
 	// to be read.
-	{-5 * time.Second, [2]error{errTimeout, errTimeout}},
+	{-5 * time.Second, [2]error{poll.ErrTimeout, poll.ErrTimeout}},
 
-	{50 * time.Millisecond, [2]error{nil, errTimeout}},
+	{50 * time.Millisecond, [2]error{nil, poll.ErrTimeout}},
 }
 
 func TestReadFromTimeout(t *testing.T) {
@@ -496,9 +497,9 @@
 }{
 	// Tests that write deadlines work, even if there's buffer
 	// space available to write.
-	{-5 * time.Second, [2]error{errTimeout, errTimeout}},
+	{-5 * time.Second, [2]error{poll.ErrTimeout, poll.ErrTimeout}},
 
-	{10 * time.Millisecond, [2]error{nil, errTimeout}},
+	{10 * time.Millisecond, [2]error{nil, poll.ErrTimeout}},
 }
 
 func TestWriteTimeout(t *testing.T) {
@@ -610,9 +611,9 @@
 }{
 	// Tests that write deadlines work, even if there's buffer
 	// space available to write.
-	{-5 * time.Second, [2]error{errTimeout, errTimeout}},
+	{-5 * time.Second, [2]error{poll.ErrTimeout, poll.ErrTimeout}},
 
-	{10 * time.Millisecond, [2]error{nil, errTimeout}},
+	{10 * time.Millisecond, [2]error{nil, poll.ErrTimeout}},
 }
 
 func TestWriteToTimeout(t *testing.T) {
diff --git a/libgo/go/net/udpsock.go b/libgo/go/net/udpsock.go
index 841ef53..2c0f74f 100644
--- a/libgo/go/net/udpsock.go
+++ b/libgo/go/net/udpsock.go
@@ -53,28 +53,34 @@
 	return a
 }
 
-// ResolveUDPAddr parses addr as a UDP address of the form "host:port"
-// or "[ipv6-host%zone]:port" and resolves a pair of domain name and
-// port name on the network net, which must be "udp", "udp4" or
-// "udp6".  A literal address or host name for IPv6 must be enclosed
-// in square brackets, as in "[::1]:80", "[ipv6-host]:http" or
-// "[ipv6-host%zone]:80".
+// ResolveUDPAddr returns an address of UDP end point.
 //
-// Resolving a hostname is not recommended because this returns at most
-// one of its IP addresses.
-func ResolveUDPAddr(net, addr string) (*UDPAddr, error) {
-	switch net {
+// The network must be a UDP network name.
+//
+// If the host in the address parameter is not a literal IP address or
+// the port is not a literal port number, ResolveUDPAddr resolves the
+// address to an address of UDP end point.
+// Otherwise, it parses the address as a pair of literal IP address
+// and port number.
+// The address parameter can use a host name, but this is not
+// recommended, because it will return at most one of the host name's
+// IP addresses.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func ResolveUDPAddr(network, address string) (*UDPAddr, error) {
+	switch network {
 	case "udp", "udp4", "udp6":
 	case "": // a hint wildcard for Go 1.0 undocumented behavior
-		net = "udp"
+		network = "udp"
 	default:
-		return nil, UnknownNetworkError(net)
+		return nil, UnknownNetworkError(network)
 	}
-	addrs, err := DefaultResolver.internetAddrList(context.Background(), net, addr)
+	addrs, err := DefaultResolver.internetAddrList(context.Background(), network, address)
 	if err != nil {
 		return nil, err
 	}
-	return addrs.first(isIPv4).(*UDPAddr), nil
+	return addrs.forResolve(network, address).(*UDPAddr), nil
 }
 
 // UDPConn is the implementation of the Conn and PacketConn interfaces
@@ -83,13 +89,16 @@
 	conn
 }
 
-// ReadFromUDP reads a UDP packet from c, copying the payload into b.
-// It returns the number of bytes copied into b and the return address
-// that was on the packet.
-//
-// ReadFromUDP can be made to time out and return an error with
-// Timeout() == true after a fixed time limit; see SetDeadline and
-// SetReadDeadline.
+// SyscallConn returns a raw network connection.
+// This implements the syscall.Conn interface.
+func (c *UDPConn) SyscallConn() (syscall.RawConn, error) {
+	if !c.ok() {
+		return nil, syscall.EINVAL
+	}
+	return newRawConn(c.fd)
+}
+
+// ReadFromUDP acts like ReadFrom but returns a UDPAddr.
 func (c *UDPConn) ReadFromUDP(b []byte) (int, *UDPAddr, error) {
 	if !c.ok() {
 		return 0, nil, syscall.EINVAL
@@ -116,11 +125,13 @@
 	return n, addr, err
 }
 
-// ReadMsgUDP reads a packet from c, copying the payload into b and
-// the associated out-of-band data into oob. It returns the number
-// of bytes copied into b, the number of bytes copied into oob, the
-// flags that were set on the packet and the source address of the
-// packet.
+// ReadMsgUDP reads a message from c, copying the payload into b and
+// the associated out-of-band data into oob. It returns the number of
+// bytes copied into b, the number of bytes copied into oob, the flags
+// that were set on the message and the source address of the message.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
 func (c *UDPConn) ReadMsgUDP(b, oob []byte) (n, oobn, flags int, addr *UDPAddr, err error) {
 	if !c.ok() {
 		return 0, 0, 0, nil, syscall.EINVAL
@@ -132,13 +143,7 @@
 	return
 }
 
-// WriteToUDP writes a UDP packet to addr via c, copying the payload
-// from b.
-//
-// WriteToUDP can be made to time out and return an error with
-// Timeout() == true after a fixed time limit; see SetDeadline and
-// SetWriteDeadline. On packet-oriented connections, write timeouts
-// are rare.
+// WriteToUDP acts like WriteTo but takes a UDPAddr.
 func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error) {
 	if !c.ok() {
 		return 0, syscall.EINVAL
@@ -166,11 +171,14 @@
 	return n, err
 }
 
-// WriteMsgUDP writes a packet to addr via c if c isn't connected, or
-// to c's remote destination address if c is connected (in which case
-// addr must be nil).  The payload is copied from b and the associated
-// out-of-band data is copied from oob. It returns the number of
-// payload and out-of-band bytes written.
+// WriteMsgUDP writes a message to addr via c if c isn't connected, or
+// to c's remote address if c is connected (in which case addr must be
+// nil). The payload is copied from b and the associated out-of-band
+// data is copied from oob. It returns the number of payload and
+// out-of-band bytes written.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
 func (c *UDPConn) WriteMsgUDP(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) {
 	if !c.ok() {
 		return 0, 0, syscall.EINVAL
@@ -184,55 +192,67 @@
 
 func newUDPConn(fd *netFD) *UDPConn { return &UDPConn{conn{fd}} }
 
-// DialUDP connects to the remote address raddr on the network net,
-// which must be "udp", "udp4", or "udp6".  If laddr is not nil, it is
-// used as the local address for the connection.
-func DialUDP(net string, laddr, raddr *UDPAddr) (*UDPConn, error) {
-	switch net {
+// DialUDP acts like Dial for UDP networks.
+//
+// The network must be a UDP network name; see func Dial for details.
+//
+// If laddr is nil, a local address is automatically chosen.
+// If the IP field of raddr is nil or an unspecified IP address, the
+// local system is assumed.
+func DialUDP(network string, laddr, raddr *UDPAddr) (*UDPConn, error) {
+	switch network {
 	case "udp", "udp4", "udp6":
 	default:
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(net)}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(network)}
 	}
 	if raddr == nil {
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
 	}
-	c, err := dialUDP(context.Background(), net, laddr, raddr)
+	c, err := dialUDP(context.Background(), network, laddr, raddr)
 	if err != nil {
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
 	}
 	return c, nil
 }
 
-// ListenUDP listens for incoming UDP packets addressed to the local
-// address laddr. Net must be "udp", "udp4", or "udp6".  If laddr has
-// a port of 0, ListenUDP will choose an available port.
-// The LocalAddr method of the returned UDPConn can be used to
-// discover the port. The returned connection's ReadFrom and WriteTo
-// methods can be used to receive and send UDP packets with per-packet
-// addressing.
-func ListenUDP(net string, laddr *UDPAddr) (*UDPConn, error) {
-	switch net {
+// ListenUDP acts like ListenPacket for UDP networks.
+//
+// The network must be a UDP network name; see func Dial for details.
+//
+// If the IP field of laddr is nil or an unspecified IP address,
+// ListenUDP listens on all available IP addresses of the local system
+// except multicast IP addresses.
+// If the Port field of laddr is 0, a port number is automatically
+// chosen.
+func ListenUDP(network string, laddr *UDPAddr) (*UDPConn, error) {
+	switch network {
 	case "udp", "udp4", "udp6":
 	default:
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(net)}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(network)}
 	}
 	if laddr == nil {
 		laddr = &UDPAddr{}
 	}
-	c, err := listenUDP(context.Background(), net, laddr)
+	c, err := listenUDP(context.Background(), network, laddr)
 	if err != nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
 	}
 	return c, nil
 }
 
-// ListenMulticastUDP listens for incoming multicast UDP packets
-// addressed to the group address gaddr on the interface ifi.
-// Network must be "udp", "udp4" or "udp6".
-// ListenMulticastUDP uses the system-assigned multicast interface
-// when ifi is nil, although this is not recommended because the
+// ListenMulticastUDP acts like ListenPacket for UDP networks but
+// takes a group address on a specific network interface.
+//
+// The network must be a UDP network name; see func Dial for details.
+//
+// ListenMulticastUDP listens on all available IP addresses of the
+// local system including the group, multicast IP address.
+// If ifi is nil, ListenMulticastUDP uses the system-assigned
+// multicast interface, although this is not recommended because the
 // assignment depends on platforms and sometimes it might require
 // routing configuration.
+// If the Port field of gaddr is 0, a port number is automatically
+// chosen.
 //
 // ListenMulticastUDP is just for convenience of simple, small
 // applications. There are golang.org/x/net/ipv4 and
diff --git a/libgo/go/net/udpsock_posix.go b/libgo/go/net/udpsock_posix.go
index 0c905af..fe552ba 100644
--- a/libgo/go/net/udpsock_posix.go
+++ b/libgo/go/net/udpsock_posix.go
@@ -16,7 +16,7 @@
 	case *syscall.SockaddrInet4:
 		return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port}
 	case *syscall.SockaddrInet6:
-		return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneToString(int(sa.ZoneId))}
+		return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
 	}
 	return nil
 }
@@ -49,7 +49,7 @@
 	case *syscall.SockaddrInet4:
 		addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port}
 	case *syscall.SockaddrInet6:
-		addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneToString(int(sa.ZoneId))}
+		addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
 	}
 	return n, addr, err
 }
@@ -61,7 +61,7 @@
 	case *syscall.SockaddrInet4:
 		addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port}
 	case *syscall.SockaddrInet6:
-		addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneToString(int(sa.ZoneId))}
+		addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
 	}
 	return
 }
diff --git a/libgo/go/net/udpsock_test.go b/libgo/go/net/udpsock_test.go
index 708cc10..6d4974e 100644
--- a/libgo/go/net/udpsock_test.go
+++ b/libgo/go/net/udpsock_test.go
@@ -15,7 +15,7 @@
 func BenchmarkUDP6LinkLocalUnicast(b *testing.B) {
 	testHookUninstaller.Do(uninstallTestHooks)
 
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		b.Skip("IPv6 is not supported")
 	}
 	ifi := loopbackInterface()
@@ -279,7 +279,7 @@
 func TestIPv6LinkLocalUnicastUDP(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 
-	if !supportsIPv6 {
+	if !supportsIPv6() {
 		t.Skip("IPv6 is not supported")
 	}
 
diff --git a/libgo/go/net/unixsock.go b/libgo/go/net/unixsock.go
index b25d492..057940a 100644
--- a/libgo/go/net/unixsock.go
+++ b/libgo/go/net/unixsock.go
@@ -42,15 +42,18 @@
 	return a
 }
 
-// ResolveUnixAddr parses addr as a Unix domain socket address.
-// The string net gives the network name, "unix", "unixgram" or
-// "unixpacket".
-func ResolveUnixAddr(net, addr string) (*UnixAddr, error) {
-	switch net {
+// ResolveUnixAddr returns an address of Unix domain socket end point.
+//
+// The network must be a Unix network name.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func ResolveUnixAddr(network, address string) (*UnixAddr, error) {
+	switch network {
 	case "unix", "unixgram", "unixpacket":
-		return &UnixAddr{Name: addr, Net: net}, nil
+		return &UnixAddr{Name: address, Net: network}, nil
 	default:
-		return nil, UnknownNetworkError(net)
+		return nil, UnknownNetworkError(network)
 	}
 }
 
@@ -60,6 +63,15 @@
 	conn
 }
 
+// SyscallConn returns a raw network connection.
+// This implements the syscall.Conn interface.
+func (c *UnixConn) SyscallConn() (syscall.RawConn, error) {
+	if !c.ok() {
+		return nil, syscall.EINVAL
+	}
+	return newRawConn(c.fd)
+}
+
 // CloseRead shuts down the reading side of the Unix domain connection.
 // Most callers should just use Close.
 func (c *UnixConn) CloseRead() error {
@@ -84,13 +96,7 @@
 	return nil
 }
 
-// ReadFromUnix reads a packet from c, copying the payload into b. It
-// returns the number of bytes copied into b and the source address of
-// the packet.
-//
-// ReadFromUnix can be made to time out and return an error with
-// Timeout() == true after a fixed time limit; see SetDeadline and
-// SetReadDeadline.
+// ReadFromUnix acts like ReadFrom but returns a UnixAddr.
 func (c *UnixConn) ReadFromUnix(b []byte) (int, *UnixAddr, error) {
 	if !c.ok() {
 		return 0, nil, syscall.EINVAL
@@ -117,10 +123,10 @@
 	return n, addr, err
 }
 
-// ReadMsgUnix reads a packet from c, copying the payload into b and
+// ReadMsgUnix reads a message from c, copying the payload into b and
 // the associated out-of-band data into oob. It returns the number of
 // bytes copied into b, the number of bytes copied into oob, the flags
-// that were set on the packet, and the source address of the packet.
+// that were set on the message and the source address of the message.
 //
 // Note that if len(b) == 0 and len(oob) > 0, this function will still
 // read (and discard) 1 byte from the connection.
@@ -135,12 +141,7 @@
 	return
 }
 
-// WriteToUnix writes a packet to addr via c, copying the payload from b.
-//
-// WriteToUnix can be made to time out and return an error with
-// Timeout() == true after a fixed time limit; see SetDeadline and
-// SetWriteDeadline. On packet-oriented connections, write timeouts
-// are rare.
+// WriteToUnix acts like WriteTo but takes a UnixAddr.
 func (c *UnixConn) WriteToUnix(b []byte, addr *UnixAddr) (int, error) {
 	if !c.ok() {
 		return 0, syscall.EINVAL
@@ -168,9 +169,9 @@
 	return n, err
 }
 
-// WriteMsgUnix writes a packet to addr via c, copying the payload
-// from b and the associated out-of-band data from oob. It returns
-// the number of payload and out-of-band bytes written.
+// WriteMsgUnix writes a message to addr via c, copying the payload
+// from b and the associated out-of-band data from oob. It returns the
+// number of payload and out-of-band bytes written.
 //
 // Note that if len(b) == 0 and len(oob) > 0, this function will still
 // write 1 byte to the connection.
@@ -187,18 +188,21 @@
 
 func newUnixConn(fd *netFD) *UnixConn { return &UnixConn{conn{fd}} }
 
-// DialUnix connects to the remote address raddr on the network net,
-// which must be "unix", "unixgram" or "unixpacket".  If laddr is not
-// nil, it is used as the local address for the connection.
-func DialUnix(net string, laddr, raddr *UnixAddr) (*UnixConn, error) {
-	switch net {
+// DialUnix acts like Dial for Unix networks.
+//
+// The network must be a Unix network name; see func Dial for details.
+//
+// If laddr is non-nil, it is used as the local address for the
+// connection.
+func DialUnix(network string, laddr, raddr *UnixAddr) (*UnixConn, error) {
+	switch network {
 	case "unix", "unixgram", "unixpacket":
 	default:
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(net)}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(network)}
 	}
-	c, err := dialUnix(context.Background(), net, laddr, raddr)
+	c, err := dialUnix(context.Background(), network, laddr, raddr)
 	if err != nil {
-		return nil, &OpError{Op: "dial", Net: net, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
 	}
 	return c, nil
 }
@@ -264,7 +268,7 @@
 	if !l.ok() {
 		return syscall.EINVAL
 	}
-	if err := l.fd.setDeadline(t); err != nil {
+	if err := l.fd.pfd.SetDeadline(t); err != nil {
 		return &OpError{Op: "set", Net: l.fd.net, Source: nil, Addr: l.fd.laddr, Err: err}
 	}
 	return nil
@@ -288,40 +292,40 @@
 	return
 }
 
-// ListenUnix announces on the Unix domain socket laddr and returns a
-// Unix listener. The network net must be "unix" or "unixpacket".
-func ListenUnix(net string, laddr *UnixAddr) (*UnixListener, error) {
-	switch net {
+// ListenUnix acts like Listen for Unix networks.
+//
+// The network must be "unix" or "unixpacket".
+func ListenUnix(network string, laddr *UnixAddr) (*UnixListener, error) {
+	switch network {
 	case "unix", "unixpacket":
 	default:
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(net)}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(network)}
 	}
 	if laddr == nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: errMissingAddress}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: errMissingAddress}
 	}
-	ln, err := listenUnix(context.Background(), net, laddr)
+	ln, err := listenUnix(context.Background(), network, laddr)
 	if err != nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
 	}
 	return ln, nil
 }
 
-// ListenUnixgram listens for incoming Unix datagram packets addressed
-// to the local address laddr. The network net must be "unixgram".
-// The returned connection's ReadFrom and WriteTo methods can be used
-// to receive and send packets with per-packet addressing.
-func ListenUnixgram(net string, laddr *UnixAddr) (*UnixConn, error) {
-	switch net {
+// ListenUnixgram acts like ListenPacket for Unix networks.
+//
+// The network must be "unixgram".
+func ListenUnixgram(network string, laddr *UnixAddr) (*UnixConn, error) {
+	switch network {
 	case "unixgram":
 	default:
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(net)}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(network)}
 	}
 	if laddr == nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: nil, Err: errMissingAddress}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: errMissingAddress}
 	}
-	c, err := listenUnixgram(context.Background(), net, laddr)
+	c, err := listenUnixgram(context.Background(), network, laddr)
 	if err != nil {
-		return nil, &OpError{Op: "listen", Net: net, Source: nil, Addr: laddr.opAddr(), Err: err}
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
 	}
 	return c, nil
 }
diff --git a/libgo/go/net/url/url.go b/libgo/go/net/url/url.go
index 42a514b..2ac2472 100644
--- a/libgo/go/net/url/url.go
+++ b/libgo/go/net/url/url.go
@@ -309,9 +309,10 @@
 }
 
 // A URL represents a parsed URL (technically, a URI reference).
+//
 // The general form represented is:
 //
-//	scheme://[userinfo@]host/path[?query][#fragment]
+//	[scheme:][//[userinfo@]host][/]path[?query][#fragment]
 //
 // URLs that do not start with a slash after the scheme are interpreted as:
 //
@@ -321,26 +322,19 @@
 // A consequence is that it is impossible to tell which slashes in the Path were
 // slashes in the raw URL and which were %2f. This distinction is rarely important,
 // but when it is, code must not use Path directly.
-//
-// Go 1.5 introduced the RawPath field to hold the encoded form of Path.
 // The Parse function sets both Path and RawPath in the URL it returns,
 // and URL's String method uses RawPath if it is a valid encoding of Path,
 // by calling the EscapedPath method.
-//
-// In earlier versions of Go, the more indirect workarounds were that an
-// HTTP server could consult req.RequestURI and an HTTP client could
-// construct a URL struct directly and set the Opaque field instead of Path.
-// These still work as well.
 type URL struct {
 	Scheme     string
 	Opaque     string    // encoded opaque data
 	User       *Userinfo // username and password information
 	Host       string    // host or host:port
-	Path       string
-	RawPath    string // encoded path hint (Go 1.5 and later only; see EscapedPath method)
-	ForceQuery bool   // append a query ('?') even if RawQuery is empty
-	RawQuery   string // encoded query values, without '?'
-	Fragment   string // fragment for references, without '#'
+	Path       string    // path (relative paths may omit leading slash)
+	RawPath    string    // encoded path hint (see EscapedPath method)
+	ForceQuery bool      // append a query ('?') even if RawQuery is empty
+	RawQuery   string    // encoded query values, without '?'
+	Fragment   string    // fragment for references, without '#'
 }
 
 // User returns a Userinfo containing the provided username
@@ -351,6 +345,7 @@
 
 // UserPassword returns a Userinfo containing the provided username
 // and password.
+//
 // This functionality should only be used with legacy web sites.
 // RFC 2396 warns that interpreting Userinfo this way
 // ``is NOT RECOMMENDED, because the passing of authentication
@@ -974,6 +969,8 @@
 }
 
 // Query parses RawQuery and returns the corresponding values.
+// It silently discards malformed value pairs.
+// To check errors use ParseQuery.
 func (u *URL) Query() Values {
 	v, _ := ParseQuery(u.RawQuery)
 	return v
diff --git a/libgo/go/net/writev_test.go b/libgo/go/net/writev_test.go
index 7160d28..4c05be4 100644
--- a/libgo/go/net/writev_test.go
+++ b/libgo/go/net/writev_test.go
@@ -7,6 +7,7 @@
 import (
 	"bytes"
 	"fmt"
+	"internal/poll"
 	"io"
 	"io/ioutil"
 	"reflect"
@@ -99,13 +100,13 @@
 }
 
 func testBuffer_writeTo(t *testing.T, chunks int, useCopy bool) {
-	oldHook := testHookDidWritev
-	defer func() { testHookDidWritev = oldHook }()
+	oldHook := poll.TestHookDidWritev
+	defer func() { poll.TestHookDidWritev = oldHook }()
 	var writeLog struct {
 		sync.Mutex
 		log []int
 	}
-	testHookDidWritev = func(size int) {
+	poll.TestHookDidWritev = func(size int) {
 		writeLog.Lock()
 		writeLog.log = append(writeLog.log, size)
 		writeLog.Unlock()
diff --git a/libgo/go/net/writev_unix.go b/libgo/go/net/writev_unix.go
index 174e6bc..bf0fbf8 100644
--- a/libgo/go/net/writev_unix.go
+++ b/libgo/go/net/writev_unix.go
@@ -7,10 +7,8 @@
 package net
 
 import (
-	"io"
-	"os"
+	"runtime"
 	"syscall"
-	"unsafe"
 )
 
 func (c *conn) writeBuffers(v *Buffers) (int64, error) {
@@ -25,71 +23,7 @@
 }
 
 func (fd *netFD) writeBuffers(v *Buffers) (n int64, err error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(); err != nil {
-		return 0, err
-	}
-
-	var iovecs []syscall.Iovec
-	if fd.iovecs != nil {
-		iovecs = *fd.iovecs
-	}
-	// TODO: read from sysconf(_SC_IOV_MAX)? The Linux default is
-	// 1024 and this seems conservative enough for now. Darwin's
-	// UIO_MAXIOV also seems to be 1024.
-	maxVec := 1024
-
-	for len(*v) > 0 {
-		iovecs = iovecs[:0]
-		for _, chunk := range *v {
-			if len(chunk) == 0 {
-				continue
-			}
-			iovecs = append(iovecs, syscall.Iovec{Base: &chunk[0]})
-			if fd.isStream && len(chunk) > 1<<30 {
-				iovecs[len(iovecs)-1].SetLen(1 << 30)
-				break // continue chunk on next writev
-			}
-			iovecs[len(iovecs)-1].SetLen(len(chunk))
-			if len(iovecs) == maxVec {
-				break
-			}
-		}
-		if len(iovecs) == 0 {
-			break
-		}
-		fd.iovecs = &iovecs // cache
-
-		wrote, _, e0 := syscall.Syscall(syscall.SYS_WRITEV,
-			uintptr(fd.sysfd),
-			uintptr(unsafe.Pointer(&iovecs[0])),
-			uintptr(len(iovecs)))
-		if wrote == ^uintptr(0) {
-			wrote = 0
-		}
-		testHookDidWritev(int(wrote))
-		n += int64(wrote)
-		v.consume(int64(wrote))
-		if e0 == syscall.EAGAIN {
-			if err = fd.pd.waitWrite(); err == nil {
-				continue
-			}
-		} else if e0 != 0 {
-			err = syscall.Errno(e0)
-		}
-		if err != nil {
-			break
-		}
-		if n == 0 {
-			err = io.ErrUnexpectedEOF
-			break
-		}
-	}
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError("writev", err)
-	}
-	return n, err
+	n, err = fd.pfd.Writev((*[][]byte)(v))
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError("writev", err)
 }
diff --git a/libgo/go/os/error_posix.go b/libgo/go/os/error_posix.go
new file mode 100644
index 0000000..2049e44
--- /dev/null
+++ b/libgo/go/os/error_posix.go
@@ -0,0 +1,18 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
+
+package os
+
+import "syscall"
+
+// wrapSyscallError takes an error and a syscall name. If the error is
+// a syscall.Errno, it wraps it in a os.SyscallError using the syscall name.
+func wrapSyscallError(name string, err error) error {
+	if _, ok := err.(syscall.Errno); ok {
+		err = NewSyscallError(name, err)
+	}
+	return err
+}
diff --git a/libgo/go/os/example_test.go b/libgo/go/os/example_test.go
index 07f9c76..5749194 100644
--- a/libgo/go/os/example_test.go
+++ b/libgo/go/os/example_test.go
@@ -21,6 +21,20 @@
 	}
 }
 
+func ExampleOpenFile_append() {
+	// If the file doesn't exist, create it, or append to the file
+	f, err := os.OpenFile("access.log", os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+	if err != nil {
+		log.Fatal(err)
+	}
+	if _, err := f.Write([]byte("appended some data\n")); err != nil {
+		log.Fatal(err)
+	}
+	if err := f.Close(); err != nil {
+		log.Fatal(err)
+	}
+}
+
 func ExampleChmod() {
 	if err := os.Chmod("some-filename", 0644); err != nil {
 		log.Fatal(err)
@@ -36,7 +50,7 @@
 }
 
 func ExampleFileMode() {
-	fi, err := os.Stat("some-filename")
+	fi, err := os.Lstat("some-filename")
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/libgo/go/os/exec/env_test.go b/libgo/go/os/exec/env_test.go
new file mode 100644
index 0000000..b5ac398
--- /dev/null
+++ b/libgo/go/os/exec/env_test.go
@@ -0,0 +1,39 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package exec
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestDedupEnv(t *testing.T) {
+	tests := []struct {
+		noCase bool
+		in     []string
+		want   []string
+	}{
+		{
+			noCase: true,
+			in:     []string{"k1=v1", "k2=v2", "K1=v3"},
+			want:   []string{"K1=v3", "k2=v2"},
+		},
+		{
+			noCase: false,
+			in:     []string{"k1=v1", "K1=V2", "k1=v3"},
+			want:   []string{"k1=v3", "K1=V2"},
+		},
+		{
+			in:   []string{"=a", "=b", "foo", "bar"},
+			want: []string{"=b", "foo", "bar"},
+		},
+	}
+	for _, tt := range tests {
+		got := dedupEnvCase(tt.noCase, tt.in)
+		if !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("Dedup(%v, %q) = %q; want %q", tt.noCase, tt.in, got, tt.want)
+		}
+	}
+}
diff --git a/libgo/go/os/exec/exec.go b/libgo/go/os/exec/exec.go
index c4c5168..893d8ee 100644
--- a/libgo/go/os/exec/exec.go
+++ b/libgo/go/os/exec/exec.go
@@ -6,6 +6,15 @@
 // easier to remap stdin and stdout, connect I/O with pipes, and do other
 // adjustments.
 //
+// Unlike the "system" library call from C and other languages, the
+// os/exec package intentionally does not invoke the system shell and
+// does not expand any glob patterns or handle other expansions,
+// pipelines, or redirections typically done by shells. The package
+// behaves more like C's "exec" family of functions. To expand glob
+// patterns, either call the shell directly, taking care to escape any
+// dangerous input, or use the path/filepath package's Glob function.
+// To expand environment variables, use package os's ExpandEnv.
+//
 // Note that the examples in this package assume a Unix system.
 // They may not run on Windows, and they do not run in the Go Playground
 // used by golang.org and godoc.org.
@@ -55,7 +64,11 @@
 	Args []string
 
 	// Env specifies the environment of the process.
-	// If Env is nil, Run uses the current process's environment.
+	// Each entry is of the form "key=value".
+	// If Env is nil, the new process uses the current process's
+	// environment.
+	// If Env contains duplicate environment keys, only the last
+	// value in the slice for each duplicate key is used.
 	Env []string
 
 	// Dir specifies the working directory of the command.
@@ -79,17 +92,14 @@
 	// If either is nil, Run connects the corresponding file descriptor
 	// to the null device (os.DevNull).
 	//
-	// If Stdout and Stderr are the same writer, at most one
-	// goroutine at a time will call Write.
+	// If Stdout and Stderr are the same writer, and have a type that can be compared with ==,
+	// at most one goroutine at a time will call Write.
 	Stdout io.Writer
 	Stderr io.Writer
 
 	// ExtraFiles specifies additional open files to be inherited by the
 	// new process. It does not include standard input, standard output, or
 	// standard error. If non-nil, entry i becomes file descriptor 3+i.
-	//
-	// BUG(rsc): On OS X 10.6, child processes may sometimes inherit unwanted fds.
-	// https://golang.org/issue/2603
 	ExtraFiles []*os.File
 
 	// SysProcAttr holds optional, operating system-specific attributes.
@@ -270,9 +280,8 @@
 // copying stdin, stdout, and stderr, and exits with a zero exit
 // status.
 //
-// If the command fails to run or doesn't complete successfully, the
-// error is of type *ExitError. Other error types may be
-// returned for I/O problems.
+// If the command starts but does not complete successfully, the error is of
+// type *ExitError. Other error types may be returned for other situations.
 func (c *Cmd) Run() error {
 	if err := c.Start(); err != nil {
 		return err
@@ -354,7 +363,7 @@
 	c.Process, err = os.StartProcess(c.Path, c.argv(), &os.ProcAttr{
 		Dir:   c.Dir,
 		Files: c.childFiles,
-		Env:   c.envv(),
+		Env:   dedupEnv(c.envv()),
 		Sys:   c.SysProcAttr,
 	})
 	if err != nil {
@@ -407,8 +416,10 @@
 	return e.ProcessState.String()
 }
 
-// Wait waits for the command to exit.
-// It must have been started by Start.
+// Wait waits for the command to exit and waits for any copying to
+// stdin or copying from stdout or stderr to complete.
+//
+// The command must have been started by Start.
 //
 // The returned error is nil if the command runs, has no problems
 // copying stdin, stdout, and stderr, and exits with a zero exit
@@ -712,3 +723,35 @@
 	}
 	return b
 }
+
+// dedupEnv returns a copy of env with any duplicates removed, in favor of
+// later values.
+// Items not of the normal environment "key=value" form are preserved unchanged.
+func dedupEnv(env []string) []string {
+	return dedupEnvCase(runtime.GOOS == "windows", env)
+}
+
+// dedupEnvCase is dedupEnv with a case option for testing.
+// If caseInsensitive is true, the case of keys is ignored.
+func dedupEnvCase(caseInsensitive bool, env []string) []string {
+	out := make([]string, 0, len(env))
+	saw := map[string]int{} // key => index into out
+	for _, kv := range env {
+		eq := strings.Index(kv, "=")
+		if eq < 0 {
+			out = append(out, kv)
+			continue
+		}
+		k := kv[:eq]
+		if caseInsensitive {
+			k = strings.ToLower(k)
+		}
+		if dupIdx, isDup := saw[k]; isDup {
+			out[dupIdx] = kv
+			continue
+		}
+		saw[k] = len(out)
+		out = append(out, kv)
+	}
+	return out
+}
diff --git a/libgo/go/os/exec/exec_posix_test.go b/libgo/go/os/exec/exec_posix_test.go
new file mode 100644
index 0000000..865b6c3
--- /dev/null
+++ b/libgo/go/os/exec/exec_posix_test.go
@@ -0,0 +1,83 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package exec_test
+
+import (
+	"os/user"
+	"strconv"
+	"syscall"
+	"testing"
+	"time"
+)
+
+func TestCredentialNoSetGroups(t *testing.T) {
+	u, err := user.Current()
+	if err != nil {
+		t.Fatalf("error getting current user: %v", err)
+	}
+
+	uid, err := strconv.Atoi(u.Uid)
+	if err != nil {
+		t.Fatalf("error converting Uid=%s to integer: %v", u.Uid, err)
+	}
+
+	gid, err := strconv.Atoi(u.Gid)
+	if err != nil {
+		t.Fatalf("error converting Gid=%s to integer: %v", u.Gid, err)
+	}
+
+	// If NoSetGroups is true, setgroups isn't called and cmd.Run should succeed
+	cmd := helperCommand(t, "echo", "foo")
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Credential: &syscall.Credential{
+			Uid:         uint32(uid),
+			Gid:         uint32(gid),
+			NoSetGroups: true,
+		},
+	}
+
+	if err = cmd.Run(); err != nil {
+		t.Errorf("Failed to run command: %v", err)
+	}
+}
+
+// For issue #19314: make sure that SIGSTOP does not cause the process
+// to appear done.
+func TestWaitid(t *testing.T) {
+	t.Parallel()
+
+	cmd := helperCommand(t, "sleep")
+	if err := cmd.Start(); err != nil {
+		t.Fatal(err)
+	}
+
+	// The sleeps here are unnecessary in the sense that the test
+	// should still pass, but they are useful to make it more
+	// likely that we are testing the expected state of the child.
+	time.Sleep(100 * time.Millisecond)
+
+	if err := cmd.Process.Signal(syscall.SIGSTOP); err != nil {
+		cmd.Process.Kill()
+		t.Fatal(err)
+	}
+
+	ch := make(chan error)
+	go func() {
+		ch <- cmd.Wait()
+	}()
+
+	time.Sleep(100 * time.Millisecond)
+
+	if err := cmd.Process.Signal(syscall.SIGCONT); err != nil {
+		t.Error(err)
+		syscall.Kill(cmd.Process.Pid, syscall.SIGCONT)
+	}
+
+	cmd.Process.Kill()
+
+	<-ch
+}
diff --git a/libgo/go/os/exec/exec_test.go b/libgo/go/os/exec/exec_test.go
index f136351..a877d8a 100644
--- a/libgo/go/os/exec/exec_test.go
+++ b/libgo/go/os/exec/exec_test.go
@@ -12,6 +12,7 @@
 	"bytes"
 	"context"
 	"fmt"
+	"internal/poll"
 	"internal/testenv"
 	"io"
 	"io/ioutil"
@@ -292,8 +293,51 @@
 
 // Issue 5071
 func TestPipeLookPathLeak(t *testing.T) {
-	fd0, lsof0 := numOpenFDS(t)
-	for i := 0; i < 4; i++ {
+	// If we are reading from /proc/self/fd we (should) get an exact result.
+	tolerance := 0
+
+	// Reading /proc/self/fd is more reliable than calling lsof, so try that
+	// first.
+	numOpenFDs := func() (int, []byte, error) {
+		fds, err := ioutil.ReadDir("/proc/self/fd")
+		if err != nil {
+			return 0, nil, err
+		}
+		return len(fds), nil, nil
+	}
+	want, before, err := numOpenFDs()
+	if err != nil {
+		// We encountered a problem reading /proc/self/fd (we might be on
+		// a platform that doesn't have it). Fall back onto lsof.
+		t.Logf("using lsof because: %v", err)
+		numOpenFDs = func() (int, []byte, error) {
+			// Android's stock lsof does not obey the -p option,
+			// so extra filtering is needed.
+			// https://golang.org/issue/10206
+			if runtime.GOOS == "android" {
+				// numOpenFDsAndroid handles errors itself and
+				// might skip or fail the test.
+				n, lsof := numOpenFDsAndroid(t)
+				return n, lsof, nil
+			}
+			lsof, err := exec.Command("lsof", "-b", "-n", "-p", strconv.Itoa(os.Getpid())).Output()
+			return bytes.Count(lsof, []byte("\n")), lsof, err
+		}
+
+		// lsof may see file descriptors associated with the fork itself,
+		// so we allow some extra margin if we have to use it.
+		// https://golang.org/issue/19243
+		tolerance = 5
+
+		// Retry reading the number of open file descriptors.
+		want, before, err = numOpenFDs()
+		if err != nil {
+			t.Log(err)
+			t.Skipf("skipping test; error finding or running lsof")
+		}
+	}
+
+	for i := 0; i < 6; i++ {
 		cmd := exec.Command("something-that-does-not-exist-binary")
 		cmd.StdoutPipe()
 		cmd.StderrPipe()
@@ -302,36 +346,20 @@
 			t.Fatal("unexpected success")
 		}
 	}
-	for triesLeft := 3; triesLeft >= 0; triesLeft-- {
-		open, lsof := numOpenFDS(t)
-		fdGrowth := open - fd0
-		if fdGrowth > 2 {
-			if triesLeft > 0 {
-				// Work around what appears to be a race with Linux's
-				// proc filesystem (as used by lsof). It seems to only
-				// be eventually consistent. Give it awhile to settle.
-				// See golang.org/issue/7808
-				time.Sleep(100 * time.Millisecond)
-				continue
-			}
-			t.Errorf("leaked %d fds; want ~0; have:\n%s\noriginally:\n%s", fdGrowth, lsof, lsof0)
-		}
-		break
-	}
-}
-
-func numOpenFDS(t *testing.T) (n int, lsof []byte) {
-	if runtime.GOOS == "android" {
-		// Android's stock lsof does not obey the -p option,
-		// so extra filtering is needed. (golang.org/issue/10206)
-		return numOpenFDsAndroid(t)
-	}
-
-	lsof, err := exec.Command("lsof", "-b", "-n", "-p", strconv.Itoa(os.Getpid())).Output()
+	got, after, err := numOpenFDs()
 	if err != nil {
-		t.Skip("skipping test; error finding or running lsof")
+		// numOpenFDs has already succeeded once, it should work here.
+		t.Errorf("unexpected failure: %v", err)
 	}
-	return bytes.Count(lsof, []byte("\n")), lsof
+	if got-want > tolerance {
+		t.Errorf("number of open file descriptors changed: got %v, want %v", got, want)
+		if before != nil {
+			t.Errorf("before:\n%v\n", before)
+		}
+		if after != nil {
+			t.Errorf("after:\n%v\n", after)
+		}
+	}
 }
 
 func numOpenFDsAndroid(t *testing.T) (n int, lsof []byte) {
@@ -377,12 +405,16 @@
 
 // basefds returns the number of expected file descriptors
 // to be present in a process at start.
+// stdin, stdout, stderr, epoll/kqueue
 func basefds() uintptr {
 	return os.Stderr.Fd() + 1
 }
 
 func closeUnexpectedFds(t *testing.T, m string) {
 	for fd := basefds(); fd <= 101; fd++ {
+		if fd == poll.PollDescriptor() {
+			continue
+		}
 		err := os.NewFile(fd, "").Close()
 		if err == nil {
 			t.Logf("%s: Something already leaked - closed fd %d", m, fd)
@@ -665,6 +697,11 @@
 			iargs = append(iargs, s)
 		}
 		fmt.Println(iargs...)
+	case "echoenv":
+		for _, s := range args {
+			fmt.Println(os.Getenv(s))
+		}
+		os.Exit(0)
 	case "cat":
 		if len(args) == 0 {
 			io.Copy(os.Stdout, os.Stdin)
@@ -740,6 +777,9 @@
 			// Now verify that there are no other open fds.
 			var files []*os.File
 			for wantfd := basefds() + 1; wantfd <= 100; wantfd++ {
+				if wantfd == poll.PollDescriptor() {
+					continue
+				}
 				f, err := os.Open(os.Args[0])
 				if err != nil {
 					fmt.Printf("error opening file with expected fd %d: %v", wantfd, err)
@@ -832,31 +872,50 @@
 	case "stderrfail":
 		fmt.Fprintf(os.Stderr, "some stderr text\n")
 		os.Exit(1)
+	case "sleep":
+		time.Sleep(3 * time.Second)
+		os.Exit(0)
 	default:
 		fmt.Fprintf(os.Stderr, "Unknown command %q\n", cmd)
 		os.Exit(2)
 	}
 }
 
+type delayedInfiniteReader struct{}
+
+func (delayedInfiniteReader) Read(b []byte) (int, error) {
+	time.Sleep(100 * time.Millisecond)
+	for i := range b {
+		b[i] = 'x'
+	}
+	return len(b), nil
+}
+
 // Issue 9173: ignore stdin pipe writes if the program completes successfully.
 func TestIgnorePipeErrorOnSuccess(t *testing.T) {
 	testenv.MustHaveExec(t)
 
-	// We really only care about testing this on Unixy things.
-	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
+	// We really only care about testing this on Unixy and Windowsy things.
+	if runtime.GOOS == "plan9" {
 		t.Skipf("skipping test on %q", runtime.GOOS)
 	}
 
-	cmd := helperCommand(t, "echo", "foo")
-	var out bytes.Buffer
-	cmd.Stdin = strings.NewReader(strings.Repeat("x", 10<<20))
-	cmd.Stdout = &out
-	if err := cmd.Run(); err != nil {
-		t.Fatal(err)
+	testWith := func(r io.Reader) func(*testing.T) {
+		return func(t *testing.T) {
+			cmd := helperCommand(t, "echo", "foo")
+			var out bytes.Buffer
+			cmd.Stdin = r
+			cmd.Stdout = &out
+			if err := cmd.Run(); err != nil {
+				t.Fatal(err)
+			}
+			if got, want := out.String(), "foo\n"; got != want {
+				t.Errorf("output = %q; want %q", got, want)
+			}
+		}
 	}
-	if got, want := out.String(), "foo\n"; got != want {
-		t.Errorf("output = %q; want %q", got, want)
-	}
+	t.Run("10MB", testWith(strings.NewReader(strings.Repeat("x", 10<<20))))
+	t.Run("Infinite", testWith(delayedInfiniteReader{}))
 }
 
 type badWriter struct{}
@@ -1012,3 +1071,18 @@
 		t.Logf("exit status: %v", err)
 	}
 }
+
+// test that environment variables are de-duped.
+func TestDedupEnvEcho(t *testing.T) {
+	testenv.MustHaveExec(t)
+
+	cmd := helperCommand(t, "echoenv", "FOO")
+	cmd.Env = append(cmd.Env, "FOO=bad", "FOO=good")
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got, want := strings.TrimSpace(string(out)), "good"; got != want {
+		t.Errorf("output = %q; want %q", got, want)
+	}
+}
diff --git a/libgo/go/os/exec/exec_posix.go b/libgo/go/os/exec/exec_unix.go
similarity index 94%
rename from libgo/go/os/exec/exec_posix.go
rename to libgo/go/os/exec/exec_unix.go
index 5e11137..9c3e17d 100644
--- a/libgo/go/os/exec/exec_posix.go
+++ b/libgo/go/os/exec/exec_unix.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !plan9
+// +build !plan9,!windows
 
 package exec
 
diff --git a/libgo/go/os/exec/exec_windows.go b/libgo/go/os/exec/exec_windows.go
new file mode 100644
index 0000000..af8cd97
--- /dev/null
+++ b/libgo/go/os/exec/exec_windows.go
@@ -0,0 +1,23 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package exec
+
+import (
+	"os"
+	"syscall"
+)
+
+func init() {
+	skipStdinCopyError = func(err error) bool {
+		// Ignore ERROR_BROKEN_PIPE and ERROR_NO_DATA errors copying
+		// to stdin if the program completed successfully otherwise.
+		// See Issue 20445.
+		const _ERROR_NO_DATA = syscall.Errno(0xe8)
+		pe, ok := err.(*os.PathError)
+		return ok &&
+			pe.Op == "write" && pe.Path == "|1" &&
+			(pe.Err == syscall.ERROR_BROKEN_PIPE || pe.Err == _ERROR_NO_DATA)
+	}
+}
diff --git a/libgo/go/os/exec_windows.go b/libgo/go/os/exec_windows.go
index d89db20..d5d553a 100644
--- a/libgo/go/os/exec_windows.go
+++ b/libgo/go/os/exec_windows.go
@@ -97,17 +97,79 @@
 }
 
 func init() {
-	var argc int32
-	cmd := syscall.GetCommandLine()
-	argv, e := syscall.CommandLineToArgv(cmd, &argc)
-	if e != nil {
-		return
+	p := syscall.GetCommandLine()
+	cmd := syscall.UTF16ToString((*[0xffff]uint16)(unsafe.Pointer(p))[:])
+	if len(cmd) == 0 {
+		arg0, _ := Executable()
+		Args = []string{arg0}
+	} else {
+		Args = commandLineToArgv(cmd)
 	}
-	defer syscall.LocalFree(syscall.Handle(uintptr(unsafe.Pointer(argv))))
-	Args = make([]string, argc)
-	for i, v := range (*argv)[:argc] {
-		Args[i] = syscall.UTF16ToString((*v)[:])
+}
+
+// appendBSBytes appends n '\\' bytes to b and returns the resulting slice.
+func appendBSBytes(b []byte, n int) []byte {
+	for ; n > 0; n-- {
+		b = append(b, '\\')
 	}
+	return b
+}
+
+// readNextArg splits command line string cmd into next
+// argument and command line remainder.
+func readNextArg(cmd string) (arg []byte, rest string) {
+	var b []byte
+	var inquote bool
+	var nslash int
+	for ; len(cmd) > 0; cmd = cmd[1:] {
+		c := cmd[0]
+		switch c {
+		case ' ', '\t':
+			if !inquote {
+				return appendBSBytes(b, nslash), cmd[1:]
+			}
+		case '"':
+			b = appendBSBytes(b, nslash/2)
+			if nslash%2 == 0 {
+				// use "Prior to 2008" rule from
+				// http://daviddeley.com/autohotkey/parameters/parameters.htm
+				// section 5.2 to deal with double double quotes
+				if inquote && len(cmd) > 1 && cmd[1] == '"' {
+					b = append(b, c)
+					cmd = cmd[1:]
+				}
+				inquote = !inquote
+			} else {
+				b = append(b, c)
+			}
+			nslash = 0
+			continue
+		case '\\':
+			nslash++
+			continue
+		}
+		b = appendBSBytes(b, nslash)
+		nslash = 0
+		b = append(b, c)
+	}
+	return appendBSBytes(b, nslash), ""
+}
+
+// commandLineToArgv splits a command line into individual argument
+// strings, following the Windows conventions documented
+// at http://daviddeley.com/autohotkey/parameters/parameters.htm#WINARGV
+func commandLineToArgv(cmd string) []string {
+	var args []string
+	for len(cmd) > 0 {
+		if cmd[0] == ' ' || cmd[0] == '\t' {
+			cmd = cmd[1:]
+			continue
+		}
+		var arg []byte
+		arg, cmd = readNextArg(cmd)
+		args = append(args, string(arg))
+	}
+	return args
 }
 
 func ftToDuration(ft *syscall.Filetime) time.Duration {
diff --git a/libgo/go/os/executable.go b/libgo/go/os/executable.go
index 8c21246..17eed10 100644
--- a/libgo/go/os/executable.go
+++ b/libgo/go/os/executable.go
@@ -16,8 +16,7 @@
 // The main use case is finding resources located relative to an
 // executable.
 //
-// Executable is not supported on nacl or OpenBSD (unless procfs is
-// mounted.)
+// Executable is not supported on nacl.
 func Executable() (string, error) {
 	return executable()
 }
diff --git a/libgo/go/os/executable_path.go b/libgo/go/os/executable_path.go
index 117320d..7b8b836 100644
--- a/libgo/go/os/executable_path.go
+++ b/libgo/go/os/executable_path.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build aix
+// +build aix openbsd
 
 package os
 
@@ -12,18 +12,19 @@
 var initWd, errWd = Getwd()
 
 func executable() (string, error) {
-	var err error
 	var exePath string
 	if len(Args) == 0 || Args[0] == "" {
 		return "", ErrNotExist
 	}
-	// Args[0] is an absolute path : this is the executable
 	if IsPathSeparator(Args[0][0]) {
+		// Args[0] is an absolute path, so it is the executable.
+		// Note that we only need to worry about Unix paths here.
 		exePath = Args[0]
 	} else {
 		for i := 1; i < len(Args[0]); i++ {
-			// Args[0] is a relative path : append current directory
 			if IsPathSeparator(Args[0][i]) {
+				// Args[0] is a relative path: prepend the
+				// initial working directory.
 				if errWd != nil {
 					return "", errWd
 				}
@@ -33,18 +34,15 @@
 		}
 	}
 	if exePath != "" {
-		err = isExecutable(exePath)
-		if err == nil {
-			return exePath, nil
+		if err := isExecutable(exePath); err != nil {
+			return "", err
 		}
-		// File does not exist or is not executable,
-		// this is an unexpected situation !
-		return "", err
+		return exePath, nil
 	}
-	// Search for executable in $PATH
+	// Search for executable in $PATH.
 	for _, dir := range splitPathList(Getenv("PATH")) {
 		if len(dir) == 0 {
-			continue
+			dir = "."
 		}
 		if !IsPathSeparator(dir[0]) {
 			if errWd != nil {
@@ -53,12 +51,11 @@
 			dir = initWd + string(PathSeparator) + dir
 		}
 		exePath = dir + string(PathSeparator) + Args[0]
-		err = isExecutable(exePath)
-		if err == nil {
+		switch isExecutable(exePath) {
+		case nil:
 			return exePath, nil
-		}
-		if err == ErrPermission {
-			return "", err
+		case ErrPermission:
+			return "", ErrPermission
 		}
 	}
 	return "", ErrNotExist
@@ -74,15 +71,18 @@
 	if !mode.IsRegular() {
 		return ErrPermission
 	}
-	if (mode & 0111) != 0 {
-		return nil
+	if (mode & 0111) == 0 {
+		return ErrPermission
 	}
-	return ErrPermission
+	return nil
 }
 
 // splitPathList splits a path list.
 // This is based on genSplit from strings/strings.go
 func splitPathList(pathList string) []string {
+	if pathList == "" {
+		return nil
+	}
 	n := 1
 	for i := 0; i < len(pathList); i++ {
 		if pathList[i] == PathListSeparator {
diff --git a/libgo/go/os/executable_procfs.go b/libgo/go/os/executable_procfs.go
index 69a70e1..b5fae59 100644
--- a/libgo/go/os/executable_procfs.go
+++ b/libgo/go/os/executable_procfs.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build linux netbsd openbsd dragonfly nacl
+// +build linux netbsd dragonfly nacl
 
 package os
 
@@ -23,8 +23,6 @@
 		procfn = "/proc/self/exe"
 	case "netbsd":
 		procfn = "/proc/curproc/exe"
-	case "openbsd":
-		procfn = "/proc/curproc/file"
 	case "dragonfly":
 		procfn = "/proc/curproc/file"
 	}
diff --git a/libgo/go/os/executable_test.go b/libgo/go/os/executable_test.go
index a4d8909..7800844 100644
--- a/libgo/go/os/executable_test.go
+++ b/libgo/go/os/executable_test.go
@@ -20,10 +20,6 @@
 	testenv.MustHaveExec(t) // will also execlude nacl, which doesn't support Executable anyway
 	ep, err := os.Executable()
 	if err != nil {
-		switch goos := runtime.GOOS; goos {
-		case "openbsd": // procfs is not mounted by default
-			t.Skipf("Executable failed on %s: %v, expected", goos, err)
-		}
 		t.Fatalf("Executable failed: %v", err)
 	}
 	// we want fn to be of the form "dir/prog"
@@ -32,6 +28,7 @@
 	if err != nil {
 		t.Fatalf("filepath.Rel: %v", err)
 	}
+
 	cmd := &osexec.Cmd{}
 	// make child start with a relative program path
 	cmd.Dir = dir
@@ -39,6 +36,10 @@
 	// forge argv[0] for child, so that we can verify we could correctly
 	// get real path of the executable without influenced by argv[0].
 	cmd.Args = []string{"-", "-test.run=XXXX"}
+	if runtime.GOOS == "openbsd" {
+		// OpenBSD relies on argv[0]
+		cmd.Args[0] = fn
+	}
 	cmd.Env = append(os.Environ(), fmt.Sprintf("%s=1", executable_EnvVar))
 	out, err := cmd.CombinedOutput()
 	if err != nil {
diff --git a/libgo/go/os/export_windows_test.go b/libgo/go/os/export_windows_test.go
index 3bb2d20..f36fadb 100644
--- a/libgo/go/os/export_windows_test.go
+++ b/libgo/go/os/export_windows_test.go
@@ -7,7 +7,7 @@
 // Export for testing.
 
 var (
-	FixLongPath     = fixLongPath
-	NewConsoleFile  = newConsoleFile
-	ReadConsoleFunc = &readConsole
+	FixLongPath       = fixLongPath
+	NewConsoleFile    = newConsoleFile
+	CommandLineToArgv = commandLineToArgv
 )
diff --git a/libgo/go/os/file.go b/libgo/go/os/file.go
index d45a00b..4b4d8fb 100644
--- a/libgo/go/os/file.go
+++ b/libgo/go/os/file.go
@@ -37,6 +37,8 @@
 package os
 
 import (
+	"errors"
+	"internal/poll"
 	"io"
 	"syscall"
 )
@@ -99,13 +101,7 @@
 		return 0, err
 	}
 	n, e := f.read(b)
-	if n == 0 && len(b) > 0 && e == nil {
-		return 0, io.EOF
-	}
-	if e != nil {
-		err = &PathError{"read", f.name, e}
-	}
-	return n, err
+	return n, f.wrapErr("read", e)
 }
 
 // ReadAt reads len(b) bytes from the File starting at byte offset off.
@@ -116,13 +112,15 @@
 	if err := f.checkValid("read"); err != nil {
 		return 0, err
 	}
+
+	if off < 0 {
+		return 0, &PathError{"readat", f.name, errors.New("negative offset")}
+	}
+
 	for len(b) > 0 {
 		m, e := f.pread(b, off)
-		if m == 0 && e == nil {
-			return n, io.EOF
-		}
 		if e != nil {
-			err = &PathError{"read", f.name, e}
+			err = f.wrapErr("read", e)
 			break
 		}
 		n += m
@@ -150,8 +148,9 @@
 	epipecheck(f, e)
 
 	if e != nil {
-		err = &PathError{"write", f.name, e}
+		err = f.wrapErr("write", e)
 	}
+
 	return n, err
 }
 
@@ -162,10 +161,15 @@
 	if err := f.checkValid("write"); err != nil {
 		return 0, err
 	}
+
+	if off < 0 {
+		return 0, &PathError{"writeat", f.name, errors.New("negative offset")}
+	}
+
 	for len(b) > 0 {
 		m, e := f.pwrite(b, off)
 		if e != nil {
-			err = &PathError{"write", f.name, e}
+			err = f.wrapErr("write", e)
 			break
 		}
 		n += m
@@ -189,7 +193,7 @@
 		e = syscall.EISDIR
 	}
 	if e != nil {
-		return 0, &PathError{"seek", f.name, e}
+		return 0, f.wrapErr("seek", e)
 	}
 	return r, nil
 }
@@ -226,19 +230,6 @@
 	return nil
 }
 
-// Chdir changes the current working directory to the file,
-// which must be a directory.
-// If there is an error, it will be of type *PathError.
-func (f *File) Chdir() error {
-	if err := f.checkValid("chdir"); err != nil {
-		return err
-	}
-	if e := syscall.Fchdir(f.fd); e != nil {
-		return &PathError{"chdir", f.name, e}
-	}
-	return nil
-}
-
 // Open opens the named file for reading. If successful, methods on
 // the returned file can be used for reading; the associated file
 // descriptor has mode O_RDONLY.
@@ -276,14 +267,52 @@
 	return n, err
 }
 
-// checkValid checks whether f is valid for use.
-// If not, it returns an appropriate error, perhaps incorporating the operation name op.
-func (f *File) checkValid(op string) error {
-	if f == nil {
-		return ErrInvalid
+// wrapErr wraps an error that occurred during an operation on an open file.
+// It passes io.EOF through unchanged, otherwise converts
+// poll.ErrFileClosing to ErrClosed and wraps the error in a PathError.
+func (f *File) wrapErr(op string, err error) error {
+	if err == nil || err == io.EOF {
+		return err
 	}
-	if f.fd == badFd {
-		return &PathError{op, f.name, ErrClosed}
+	if err == poll.ErrFileClosing {
+		err = ErrClosed
 	}
-	return nil
+	return &PathError{op, f.name, err}
 }
+
+// TempDir returns the default directory to use for temporary files.
+//
+// On Unix systems, it returns $TMPDIR if non-empty, else /tmp.
+// On Windows, it uses GetTempPath, returning the first non-empty
+// value from %TMP%, %TEMP%, %USERPROFILE%, or the Windows directory.
+// On Plan 9, it returns /tmp.
+//
+// The directory is neither guaranteed to exist nor have accessible
+// permissions.
+func TempDir() string {
+	return tempDir()
+}
+
+// Chmod changes the mode of the named file to mode.
+// If the file is a symbolic link, it changes the mode of the link's target.
+// If there is an error, it will be of type *PathError.
+//
+// A different subset of the mode bits are used, depending on the
+// operating system.
+//
+// On Unix, the mode's permission bits, ModeSetuid, ModeSetgid, and
+// ModeSticky are used.
+//
+// On Windows, the mode must be non-zero but otherwise only the 0200
+// bit (owner writable) of mode is used; it controls whether the
+// file's read-only attribute is set or cleared. attribute. The other
+// bits are currently unused. Use mode 0400 for a read-only file and
+// 0600 for a readable+writable file.
+//
+// On Plan 9, the mode's permission bits, ModeAppend, ModeExclusive,
+// and ModeTemporary are used.
+func Chmod(name string, mode FileMode) error { return chmod(name, mode) }
+
+// Chmod changes the mode of the file to mode.
+// If there is an error, it will be of type *PathError.
+func (f *File) Chmod(mode FileMode) error { return f.chmod(mode) }
diff --git a/libgo/go/os/file_plan9.go b/libgo/go/os/file_plan9.go
index 5276a7e..0f4a736 100644
--- a/libgo/go/os/file_plan9.go
+++ b/libgo/go/os/file_plan9.go
@@ -35,7 +35,9 @@
 	return uintptr(f.fd)
 }
 
-// NewFile returns a new File with the given file descriptor and name.
+// NewFile returns a new File with the given file descriptor and
+// name. The returned value will be nil if fd is not a valid file
+// descriptor.
 func NewFile(fd uintptr, name string) *File {
 	fdi := int(fd)
 	if fdi < 0 {
@@ -194,9 +196,7 @@
 
 const chmodMask = uint32(syscall.DMAPPEND | syscall.DMEXCL | syscall.DMTMP | ModePerm)
 
-// Chmod changes the mode of the file to mode.
-// If there is an error, it will be of type *PathError.
-func (f *File) Chmod(mode FileMode) error {
+func (f *File) chmod(mode FileMode) error {
 	if f == nil {
 		return ErrInvalid
 	}
@@ -244,14 +244,22 @@
 // read reads up to len(b) bytes from the File.
 // It returns the number of bytes read and an error, if any.
 func (f *File) read(b []byte) (n int, err error) {
-	return fixCount(syscall.Read(f.fd, b))
+	n, e := fixCount(syscall.Read(f.fd, b))
+	if n == 0 && len(b) > 0 && e == nil {
+		return 0, io.EOF
+	}
+	return n, e
 }
 
 // pread reads len(b) bytes from the File starting at byte offset off.
 // It returns the number of bytes read and the error, if any.
 // EOF is signaled by a zero count with err set to nil.
 func (f *File) pread(b []byte, off int64) (n int, err error) {
-	return fixCount(syscall.Pread(f.fd, b, off))
+	n, e := fixCount(syscall.Pread(f.fd, b, off))
+	if n == 0 && len(b) > 0 && e == nil {
+		return 0, io.EOF
+	}
+	return n, e
 }
 
 // write writes len(b) bytes to the File.
@@ -365,10 +373,8 @@
 	return nil
 }
 
-// Chmod changes the mode of the named file to mode.
-// If the file is a symbolic link, it changes the mode of the link's target.
-// If there is an error, it will be of type *PathError.
-func Chmod(name string, mode FileMode) error {
+// See docs in file.go:Chmod.
+func chmod(name string, mode FileMode) error {
 	var d syscall.Dir
 
 	odir, e := dirstat(name)
@@ -468,7 +474,31 @@
 	return &PathError{"chown", f.name, syscall.EPLAN9}
 }
 
-// TempDir returns the default directory to use for temporary files.
-func TempDir() string {
+func tempDir() string {
 	return "/tmp"
 }
+
+// Chdir changes the current working directory to the file,
+// which must be a directory.
+// If there is an error, it will be of type *PathError.
+func (f *File) Chdir() error {
+	if err := f.checkValid("chdir"); err != nil {
+		return err
+	}
+	if e := syscall.Fchdir(f.fd); e != nil {
+		return &PathError{"chdir", f.name, e}
+	}
+	return nil
+}
+
+// checkValid checks whether f is valid for use.
+// If not, it returns an appropriate error, perhaps incorporating the operation name op.
+func (f *File) checkValid(op string) error {
+	if f == nil {
+		return ErrInvalid
+	}
+	if f.fd == badFd {
+		return &PathError{op, f.name, ErrClosed}
+	}
+	return nil
+}
diff --git a/libgo/go/os/file_posix.go b/libgo/go/os/file_posix.go
index 6634112..51cae9d 100644
--- a/libgo/go/os/file_posix.go
+++ b/libgo/go/os/file_posix.go
@@ -48,24 +48,21 @@
 	return
 }
 
-// Chmod changes the mode of the named file to mode.
-// If the file is a symbolic link, it changes the mode of the link's target.
-// If there is an error, it will be of type *PathError.
-func Chmod(name string, mode FileMode) error {
-	if e := syscall.Chmod(name, syscallMode(mode)); e != nil {
+// See docs in file.go:Chmod.
+func chmod(name string, mode FileMode) error {
+	if e := syscall.Chmod(fixLongPath(name), syscallMode(mode)); e != nil {
 		return &PathError{"chmod", name, e}
 	}
 	return nil
 }
 
-// Chmod changes the mode of the file to mode.
-// If there is an error, it will be of type *PathError.
-func (f *File) Chmod(mode FileMode) error {
+// See docs in file.go:(*File).Chmod.
+func (f *File) chmod(mode FileMode) error {
 	if err := f.checkValid("chmod"); err != nil {
 		return err
 	}
-	if e := syscall.Fchmod(f.fd, syscallMode(mode)); e != nil {
-		return &PathError{"chmod", f.name, e}
+	if e := f.pfd.Fchmod(syscallMode(mode)); e != nil {
+		return f.wrapErr("chmod", e)
 	}
 	return nil
 }
@@ -73,6 +70,9 @@
 // Chown changes the numeric uid and gid of the named file.
 // If the file is a symbolic link, it changes the uid and gid of the link's target.
 // If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
 func Chown(name string, uid, gid int) error {
 	if e := syscall.Chown(name, uid, gid); e != nil {
 		return &PathError{"chown", name, e}
@@ -83,6 +83,9 @@
 // Lchown changes the numeric uid and gid of the named file.
 // If the file is a symbolic link, it changes the uid and gid of the link itself.
 // If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
 func Lchown(name string, uid, gid int) error {
 	if e := syscall.Lchown(name, uid, gid); e != nil {
 		return &PathError{"lchown", name, e}
@@ -92,12 +95,15 @@
 
 // Chown changes the numeric uid and gid of the named file.
 // If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
 func (f *File) Chown(uid, gid int) error {
 	if err := f.checkValid("chown"); err != nil {
 		return err
 	}
-	if e := syscall.Fchown(f.fd, uid, gid); e != nil {
-		return &PathError{"chown", f.name, e}
+	if e := f.pfd.Fchown(uid, gid); e != nil {
+		return f.wrapErr("chown", e)
 	}
 	return nil
 }
@@ -109,8 +115,8 @@
 	if err := f.checkValid("truncate"); err != nil {
 		return err
 	}
-	if e := syscall.Ftruncate(f.fd, size); e != nil {
-		return &PathError{"truncate", f.name, e}
+	if e := f.pfd.Ftruncate(size); e != nil {
+		return f.wrapErr("truncate", e)
 	}
 	return nil
 }
@@ -122,8 +128,8 @@
 	if err := f.checkValid("sync"); err != nil {
 		return err
 	}
-	if e := syscall.Fsync(f.fd); e != nil {
-		return &PathError{"sync", f.name, e}
+	if e := f.pfd.Fsync(); e != nil {
+		return f.wrapErr("sync", e)
 	}
 	return nil
 }
@@ -143,3 +149,25 @@
 	}
 	return nil
 }
+
+// Chdir changes the current working directory to the file,
+// which must be a directory.
+// If there is an error, it will be of type *PathError.
+func (f *File) Chdir() error {
+	if err := f.checkValid("chdir"); err != nil {
+		return err
+	}
+	if e := f.pfd.Fchdir(); e != nil {
+		return f.wrapErr("chdir", e)
+	}
+	return nil
+}
+
+// checkValid checks whether f is valid for use.
+// If not, it returns an appropriate error, perhaps incorporating the operation name op.
+func (f *File) checkValid(op string) error {
+	if f == nil {
+		return ErrInvalid
+	}
+	return nil
+}
diff --git a/libgo/go/os/file_unix.go b/libgo/go/os/file_unix.go
index 1bba4ed..8199994 100644
--- a/libgo/go/os/file_unix.go
+++ b/libgo/go/os/file_unix.go
@@ -7,6 +7,7 @@
 package os
 
 import (
+	"internal/poll"
 	"runtime"
 	"syscall"
 )
@@ -19,11 +20,22 @@
 func rename(oldname, newname string) error {
 	fi, err := Lstat(newname)
 	if err == nil && fi.IsDir() {
+		// There are two independent errors this function can return:
+		// one for a bad oldname, and one for a bad newname.
+		// At this point we've determined the newname is bad.
+		// But just in case oldname is also bad, prioritize returning
+		// the oldname error because that's what we did historically.
+		if _, err := Lstat(oldname); err != nil {
+			if pe, ok := err.(*PathError); ok {
+				err = pe.Err
+			}
+			return &LinkError{"rename", oldname, newname, err}
+		}
 		return &LinkError{"rename", oldname, newname, syscall.EEXIST}
 	}
-	e := syscall.Rename(oldname, newname)
-	if e != nil {
-		return &LinkError{"rename", oldname, newname, e}
+	err = syscall.Rename(oldname, newname)
+	if err != nil {
+		return &LinkError{"rename", oldname, newname, err}
 	}
 	return nil
 }
@@ -33,9 +45,10 @@
 // can overwrite this data, which could cause the finalizer
 // to close the wrong file descriptor.
 type file struct {
-	fd      int
-	name    string
-	dirinfo *dirInfo // nil unless directory being read
+	pfd      poll.FD
+	name     string
+	dirinfo  *dirInfo // nil unless directory being read
+	nonblock bool     // whether we set nonblocking mode
 }
 
 // Fd returns the integer Unix file descriptor referencing the open file.
@@ -44,16 +57,64 @@
 	if f == nil {
 		return ^(uintptr(0))
 	}
-	return uintptr(f.fd)
+
+	// If we put the file descriptor into nonblocking mode,
+	// then set it to blocking mode before we return it,
+	// because historically we have always returned a descriptor
+	// opened in blocking mode. The File will continue to work,
+	// but any blocking operation will tie up a thread.
+	if f.nonblock {
+		syscall.SetNonblock(f.pfd.Sysfd, false)
+	}
+
+	return uintptr(f.pfd.Sysfd)
 }
 
-// NewFile returns a new File with the given file descriptor and name.
+// NewFile returns a new File with the given file descriptor and
+// name. The returned value will be nil if fd is not a valid file
+// descriptor.
 func NewFile(fd uintptr, name string) *File {
+	return newFile(fd, name, false)
+}
+
+// newFile is like NewFile, but if pollable is true it tries to add the
+// file to the runtime poller.
+func newFile(fd uintptr, name string, pollable bool) *File {
 	fdi := int(fd)
 	if fdi < 0 {
 		return nil
 	}
-	f := &File{&file{fd: fdi, name: name}}
+	f := &File{&file{
+		pfd: poll.FD{
+			Sysfd:         fdi,
+			IsStream:      true,
+			ZeroReadIsEOF: true,
+		},
+		name: name,
+	}}
+
+	// Don't try to use kqueue with regular files on FreeBSD.
+	// It crashes the system unpredictably while running all.bash.
+	// Issue 19093.
+	if runtime.GOOS == "freebsd" {
+		pollable = false
+	}
+
+	if err := f.pfd.Init("file", pollable); err != nil {
+		// An error here indicates a failure to register
+		// with the netpoll system. That can happen for
+		// a file descriptor that is not supported by
+		// epoll/kqueue; for example, disk files on
+		// GNU/Linux systems. We assume that any real error
+		// will show up in later I/O.
+	} else if pollable {
+		// We successfully registered with netpoll, so put
+		// the file into nonblocking mode.
+		if err := syscall.SetNonblock(fdi, true); err == nil {
+			f.nonblock = true
+		}
+	}
+
 	runtime.SetFinalizer(f.file, (*file).close)
 	return f
 }
@@ -68,7 +129,7 @@
 // output or standard error. See the SIGPIPE docs in os/signal, and
 // issue 11845.
 func epipecheck(file *File, e error) {
-	if e == syscall.EPIPE && (file.fd == 1 || file.fd == 2) {
+	if e == syscall.EPIPE && (file.pfd.Sysfd == 1 || file.pfd.Sysfd == 2) {
 		sigpipe()
 	}
 }
@@ -119,7 +180,7 @@
 		syscall.CloseOnExec(r)
 	}
 
-	return NewFile(uintptr(r), name), nil
+	return newFile(uintptr(r), name, true), nil
 }
 
 // Close closes the File, rendering it unusable for I/O.
@@ -132,11 +193,14 @@
 }
 
 func (file *file) close() error {
-	if file == nil || file.fd == badFd {
+	if file == nil {
 		return syscall.EINVAL
 	}
 	var err error
-	if e := syscall.Close(file.fd); e != nil {
+	if e := file.pfd.Close(); e != nil {
+		if e == poll.ErrFileClosing {
+			e = ErrClosed
+		}
 		err = &PathError{"close", file.name, e}
 	}
 
@@ -151,76 +215,42 @@
 		}
 	}
 
-	file.fd = -1 // so it can't be closed again
-
 	// no need for a finalizer anymore
 	runtime.SetFinalizer(file, nil)
 	return err
 }
 
-// Darwin and FreeBSD can't read or write 2GB+ at a time,
-// even on 64-bit systems. See golang.org/issue/7812.
-// Use 1GB instead of, say, 2GB-1, to keep subsequent
-// reads aligned.
-const (
-	needsMaxRW = runtime.GOOS == "darwin" || runtime.GOOS == "freebsd"
-	maxRW      = 1 << 30
-)
-
 // read reads up to len(b) bytes from the File.
 // It returns the number of bytes read and an error, if any.
 func (f *File) read(b []byte) (n int, err error) {
-	if needsMaxRW && len(b) > maxRW {
-		b = b[:maxRW]
-	}
-	return fixCount(syscall.Read(f.fd, b))
+	n, err = f.pfd.Read(b)
+	runtime.KeepAlive(f)
+	return n, err
 }
 
 // pread reads len(b) bytes from the File starting at byte offset off.
 // It returns the number of bytes read and the error, if any.
 // EOF is signaled by a zero count with err set to nil.
 func (f *File) pread(b []byte, off int64) (n int, err error) {
-	if needsMaxRW && len(b) > maxRW {
-		b = b[:maxRW]
-	}
-	return fixCount(syscall.Pread(f.fd, b, off))
+	n, err = f.pfd.Pread(b, off)
+	runtime.KeepAlive(f)
+	return n, err
 }
 
 // write writes len(b) bytes to the File.
 // It returns the number of bytes written and an error, if any.
 func (f *File) write(b []byte) (n int, err error) {
-	for {
-		bcap := b
-		if needsMaxRW && len(bcap) > maxRW {
-			bcap = bcap[:maxRW]
-		}
-		m, err := fixCount(syscall.Write(f.fd, bcap))
-		n += m
-
-		// If the syscall wrote some data but not all (short write)
-		// or it returned EINTR, then assume it stopped early for
-		// reasons that are uninteresting to the caller, and try again.
-		if 0 < m && m < len(bcap) || err == syscall.EINTR {
-			b = b[m:]
-			continue
-		}
-
-		if needsMaxRW && len(bcap) != len(b) && err == nil {
-			b = b[m:]
-			continue
-		}
-
-		return n, err
-	}
+	n, err = f.pfd.Write(b)
+	runtime.KeepAlive(f)
+	return n, err
 }
 
 // pwrite writes len(b) bytes to the File starting at byte offset off.
 // It returns the number of bytes written and an error, if any.
 func (f *File) pwrite(b []byte, off int64) (n int, err error) {
-	if needsMaxRW && len(b) > maxRW {
-		b = b[:maxRW]
-	}
-	return fixCount(syscall.Pwrite(f.fd, b, off))
+	n, err = f.pfd.Pwrite(b, off)
+	runtime.KeepAlive(f)
+	return n, err
 }
 
 // seek sets the offset for the next Read or Write on file to offset, interpreted
@@ -228,7 +258,9 @@
 // relative to the current offset, and 2 means relative to the end.
 // It returns the new offset and an error, if any.
 func (f *File) seek(offset int64, whence int) (ret int64, err error) {
-	return syscall.Seek(f.fd, offset, whence)
+	ret, err = f.pfd.Seek(offset, whence)
+	runtime.KeepAlive(f)
+	return ret, err
 }
 
 // Truncate changes the size of the named file.
@@ -272,8 +304,7 @@
 	return &PathError{"remove", name, e}
 }
 
-// TempDir returns the default directory to use for temporary files.
-func TempDir() string {
+func tempDir() string {
 	dir := Getenv("TMPDIR")
 	if dir == "" {
 		if runtime.GOOS == "android" {
diff --git a/libgo/go/os/os_test.go b/libgo/go/os/os_test.go
index dcc8d76..0f1617a 100644
--- a/libgo/go/os/os_test.go
+++ b/libgo/go/os/os_test.go
@@ -17,6 +17,7 @@
 	"path/filepath"
 	"reflect"
 	"runtime"
+	"runtime/debug"
 	"sort"
 	"strings"
 	"sync"
@@ -52,15 +53,12 @@
 	case "darwin":
 		switch runtime.GOARCH {
 		case "arm", "arm64":
-			/// At this point the test harness has not had a chance
-			// to move us into the ./src/os directory, so the
-			// current working directory is the root of the app.
 			wd, err := syscall.Getwd()
 			if err != nil {
 				wd = err.Error()
 			}
 			return &sysDir{
-				wd,
+				filepath.Join(wd, "..", ".."),
 				[]string{
 					"ResourceRules.plist",
 					"Info.plist",
@@ -110,7 +108,7 @@
 			break
 		}
 		if e != nil {
-			t.Fatal("read failed:", err)
+			t.Fatal("read failed:", e)
 		}
 	}
 	return int64(len)
@@ -174,6 +172,45 @@
 	}
 }
 
+func TestStatError(t *testing.T) {
+	defer chtmpdir(t)()
+
+	path := "no-such-file"
+	Remove(path) // Just in case
+
+	fi, err := Stat(path)
+	if err == nil {
+		t.Fatal("got nil, want error")
+	}
+	if fi != nil {
+		t.Errorf("got %v, want nil", fi)
+	}
+	if perr, ok := err.(*PathError); !ok {
+		t.Errorf("got %T, want %T", err, perr)
+	}
+
+	testenv.MustHaveSymlink(t)
+
+	link := "symlink"
+	Remove(link) // Just in case
+	err = Symlink(path, link)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer Remove(link)
+
+	fi, err = Stat(link)
+	if err == nil {
+		t.Fatal("got nil, want error")
+	}
+	if fi != nil {
+		t.Errorf("got %v, want nil", fi)
+	}
+	if perr, ok := err.(*PathError); !ok {
+		t.Errorf("got %T, want %T", err, perr)
+	}
+}
+
 func TestFstat(t *testing.T) {
 	path := sfdir + "/" + sfname
 	file, err1 := Open(path)
@@ -359,6 +396,50 @@
 	benchmarkReaddir(".", b)
 }
 
+func benchmarkStat(b *testing.B, path string) {
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_, err := Stat(path)
+		if err != nil {
+			b.Fatalf("Stat(%q) failed: %v", path, err)
+		}
+	}
+}
+
+func benchmarkLstat(b *testing.B, path string) {
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_, err := Lstat(path)
+		if err != nil {
+			b.Fatalf("Lstat(%q) failed: %v", path, err)
+		}
+	}
+}
+
+func BenchmarkStatDot(b *testing.B) {
+	benchmarkStat(b, ".")
+}
+
+func BenchmarkStatFile(b *testing.B) {
+	benchmarkStat(b, filepath.Join(runtime.GOROOT(), "src/os/os_test.go"))
+}
+
+func BenchmarkStatDir(b *testing.B) {
+	benchmarkStat(b, filepath.Join(runtime.GOROOT(), "src/os"))
+}
+
+func BenchmarkLstatDot(b *testing.B) {
+	benchmarkLstat(b, ".")
+}
+
+func BenchmarkLstatFile(b *testing.B) {
+	benchmarkLstat(b, filepath.Join(runtime.GOROOT(), "src/os/os_test.go"))
+}
+
+func BenchmarkLstatDir(b *testing.B) {
+	benchmarkLstat(b, filepath.Join(runtime.GOROOT(), "src/os"))
+}
+
 // Read the directory one entry at a time.
 func smallReaddirnames(file *File, length int, t *testing.T) []string {
 	names := make([]string, length)
@@ -673,55 +754,58 @@
 	Remove(from) // Just in case.
 	file, err := Create(to)
 	if err != nil {
-		t.Fatalf("open %q failed: %v", to, err)
+		t.Fatalf("Create(%q) failed: %v", to, err)
 	}
 	defer Remove(to)
 	if err = file.Close(); err != nil {
-		t.Errorf("close %q failed: %v", to, err)
+		t.Errorf("Close(%q) failed: %v", to, err)
 	}
 	err = Symlink(to, from)
 	if err != nil {
-		t.Fatalf("symlink %q, %q failed: %v", to, from, err)
+		t.Fatalf("Symlink(%q, %q) failed: %v", to, from, err)
 	}
 	defer Remove(from)
 	tostat, err := Lstat(to)
 	if err != nil {
-		t.Fatalf("stat %q failed: %v", to, err)
+		t.Fatalf("Lstat(%q) failed: %v", to, err)
 	}
 	if tostat.Mode()&ModeSymlink != 0 {
-		t.Fatalf("stat %q claims to have found a symlink", to)
+		t.Fatalf("Lstat(%q).Mode()&ModeSymlink = %v, want 0", to, tostat.Mode()&ModeSymlink)
 	}
 	fromstat, err := Stat(from)
 	if err != nil {
-		t.Fatalf("stat %q failed: %v", from, err)
+		t.Fatalf("Stat(%q) failed: %v", from, err)
 	}
 	if !SameFile(tostat, fromstat) {
-		t.Errorf("symlink %q, %q did not create symlink", to, from)
+		t.Errorf("Symlink(%q, %q) did not create symlink", to, from)
 	}
 	fromstat, err = Lstat(from)
 	if err != nil {
-		t.Fatalf("lstat %q failed: %v", from, err)
+		t.Fatalf("Lstat(%q) failed: %v", from, err)
 	}
 	if fromstat.Mode()&ModeSymlink == 0 {
-		t.Fatalf("symlink %q, %q did not create symlink", to, from)
+		t.Fatalf("Lstat(%q).Mode()&ModeSymlink = 0, want %v", from, ModeSymlink)
 	}
 	fromstat, err = Stat(from)
 	if err != nil {
-		t.Fatalf("stat %q failed: %v", from, err)
+		t.Fatalf("Stat(%q) failed: %v", from, err)
+	}
+	if fromstat.Name() != from {
+		t.Errorf("Stat(%q).Name() = %q, want %q", from, fromstat.Name(), from)
 	}
 	if fromstat.Mode()&ModeSymlink != 0 {
-		t.Fatalf("stat %q did not follow symlink", from)
+		t.Fatalf("Stat(%q).Mode()&ModeSymlink = %v, want 0", from, fromstat.Mode()&ModeSymlink)
 	}
 	s, err := Readlink(from)
 	if err != nil {
-		t.Fatalf("readlink %q failed: %v", from, err)
+		t.Fatalf("Readlink(%q) failed: %v", from, err)
 	}
 	if s != to {
-		t.Fatalf("after symlink %q != %q", s, to)
+		t.Fatalf("Readlink(%q) = %q, want %q", from, s, to)
 	}
 	file, err = Open(from)
 	if err != nil {
-		t.Fatalf("open %q failed: %v", from, err)
+		t.Fatalf("Open(%q) failed: %v", from, err)
 	}
 	file.Close()
 }
@@ -844,6 +928,18 @@
 	}
 }
 
+func TestRenameNotExisting(t *testing.T) {
+	defer chtmpdir(t)()
+	from, to := "doesnt-exist", "dest"
+
+	Mkdir(to, 0777)
+	defer Remove(to)
+
+	if err := Rename(from, to); !IsNotExist(err) {
+		t.Errorf("Rename(%q, %q) = %v; want an IsNotExist error", from, to, err)
+	}
+}
+
 func TestRenameToDirFailed(t *testing.T) {
 	defer chtmpdir(t)()
 	from, to := "renamefrom", "renameto"
@@ -1054,14 +1150,22 @@
 	}
 	postStat := st
 
-	/* Plan 9, NaCl:
-		Mtime is the time of the last change of content.  Similarly, atime is set whenever the
-	    contents are accessed; also, it is set whenever mtime is set.
-	*/
 	pat := Atime(postStat)
 	pmt := postStat.ModTime()
-	if !pat.Before(at) && runtime.GOOS != "plan9" && runtime.GOOS != "nacl" {
-		t.Errorf("AccessTime didn't go backwards; was=%d, after=%d", at, pat)
+	if !pat.Before(at) {
+		switch runtime.GOOS {
+		case "plan9", "nacl":
+			// Ignore.
+			// Plan 9, NaCl:
+			// Mtime is the time of the last change of
+			// content.  Similarly, atime is set whenever
+			// the contents are accessed; also, it is set
+			// whenever mtime is set.
+		case "netbsd":
+			t.Logf("AccessTime didn't go backwards; was=%d, after=%d (Ignoring. See NetBSD issue golang.org/issue/19293)", at, pat)
+		default:
+			t.Errorf("AccessTime didn't go backwards; was=%d, after=%d", at, pat)
+		}
 	}
 
 	if !pmt.Before(mt) {
@@ -1239,6 +1343,32 @@
 	}
 }
 
+func TestSeekError(t *testing.T) {
+	switch runtime.GOOS {
+	case "plan9", "nacl":
+		t.Skipf("skipping test on %v", runtime.GOOS)
+	}
+
+	r, w, err := Pipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, err = r.Seek(0, 0)
+	if err == nil {
+		t.Fatal("Seek on pipe should fail")
+	}
+	if perr, ok := err.(*PathError); !ok || perr.Err != syscall.ESPIPE {
+		t.Errorf("Seek returned error %v, want &PathError{Err: syscall.ESPIPE}", err)
+	}
+	_, err = w.Seek(0, 0)
+	if err == nil {
+		t.Fatal("Seek on pipe should fail")
+	}
+	if perr, ok := err.(*PathError); !ok || perr.Err != syscall.ESPIPE {
+		t.Errorf("Seek returned error %v, want &PathError{Err: syscall.ESPIPE}", err)
+	}
+}
+
 type openErrorTest struct {
 	path  string
 	mode  int
@@ -1443,6 +1573,26 @@
 	}
 }
 
+// Verify that ReadAt doesn't allow negative offset.
+func TestReadAtNegativeOffset(t *testing.T) {
+	f := newFile("TestReadAtNegativeOffset", t)
+	defer Remove(f.Name())
+	defer f.Close()
+
+	const data = "hello, world\n"
+	io.WriteString(f, data)
+
+	f.Seek(0, 0)
+	b := make([]byte, 5)
+
+	n, err := f.ReadAt(b, -10)
+
+	const wantsub = "negative offset"
+	if !strings.Contains(fmt.Sprint(err), wantsub) || n != 0 {
+		t.Errorf("ReadAt(-10) = %v, %v; want 0, ...%q...", n, err, wantsub)
+	}
+}
+
 func TestWriteAt(t *testing.T) {
 	f := newFile("TestWriteAt", t)
 	defer Remove(f.Name())
@@ -1465,6 +1615,20 @@
 	}
 }
 
+// Verify that WriteAt doesn't allow negative offset.
+func TestWriteAtNegativeOffset(t *testing.T) {
+	f := newFile("TestWriteAtNegativeOffset", t)
+	defer Remove(f.Name())
+	defer f.Close()
+
+	n, err := f.WriteAt([]byte("WORLD"), -10)
+
+	const wantsub = "negative offset"
+	if !strings.Contains(fmt.Sprint(err), wantsub) || n != 0 {
+		t.Errorf("WriteAt(-10) = %v, %v; want 0, ...%q...", n, err, wantsub)
+	}
+}
+
 func writeFile(t *testing.T, fname string, flag int, text string) string {
 	f, err := OpenFile(fname, flag, 0666)
 	if err != nil {
@@ -1667,6 +1831,17 @@
 		Exit(0)
 	}
 
+	fi, err := Stdin.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+	switch mode := fi.Mode(); {
+	case mode&ModeCharDevice != 0:
+	case mode&ModeNamedPipe != 0:
+	default:
+		t.Fatalf("unexpected Stdin mode (%v), want ModeCharDevice or ModeNamedPipe", mode)
+	}
+
 	var cmd *osexec.Cmd
 	if runtime.GOOS == "windows" {
 		cmd = osexec.Command("cmd", "/c", "echo output | "+Args[0]+" -test.run=TestStatStdin")
@@ -1686,6 +1861,60 @@
 	}
 }
 
+func TestStatRelativeSymlink(t *testing.T) {
+	testenv.MustHaveSymlink(t)
+
+	tmpdir, err := ioutil.TempDir("", "TestStatRelativeSymlink")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer RemoveAll(tmpdir)
+
+	target := filepath.Join(tmpdir, "target")
+	f, err := Create(target)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+
+	st, err := f.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	link := filepath.Join(tmpdir, "link")
+	err = Symlink(filepath.Base(target), link)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	st1, err := Stat(link)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !SameFile(st, st1) {
+		t.Error("Stat doesn't follow relative symlink")
+	}
+
+	if runtime.GOOS == "windows" {
+		Remove(link)
+		err = Symlink(target[len(filepath.VolumeName(target)):], link)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		st1, err := Stat(link)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if !SameFile(st, st1) {
+			t.Error("Stat doesn't follow relative symlink")
+		}
+	}
+}
+
 func TestReadAtEOF(t *testing.T) {
 	f := newFile("TestReadAtEOF", t)
 	defer Remove(f.Name())
@@ -1759,6 +1988,10 @@
 					if dir.Size() != filesize || filesize != wantSize {
 						t.Errorf("Size(%q) is %d, len(ReadFile()) is %d, want %d", path, dir.Size(), filesize, wantSize)
 					}
+					err = Chmod(path, dir.Mode())
+					if err != nil {
+						t.Fatalf("Chmod(%q) failed: %v", path, err)
+					}
 				}
 				if err := Truncate(sizedTempDir+"/bar.txt", 0); err != nil {
 					t.Fatalf("Truncate failed: %v", err)
@@ -1927,3 +2160,99 @@
 	close(hold) // let workers race to remove root
 	wg.Wait()
 }
+
+// Test that reading from a pipe doesn't use up a thread.
+func TestPipeThreads(t *testing.T) {
+	switch runtime.GOOS {
+	case "freebsd":
+		t.Skip("skipping on FreeBSD; issue 19093")
+	case "solaris":
+		t.Skip("skipping on Solaris; issue 19111")
+	case "windows":
+		t.Skip("skipping on Windows; issue 19098")
+	case "plan9":
+		t.Skip("skipping on Plan 9; does not support runtime poller")
+	}
+
+	threads := 100
+
+	// OpenBSD has a low default for max number of files.
+	if runtime.GOOS == "openbsd" {
+		threads = 50
+	}
+
+	r := make([]*File, threads)
+	w := make([]*File, threads)
+	for i := 0; i < threads; i++ {
+		rp, wp, err := Pipe()
+		if err != nil {
+			for j := 0; j < i; j++ {
+				r[j].Close()
+				w[j].Close()
+			}
+			t.Fatal(err)
+		}
+		r[i] = rp
+		w[i] = wp
+	}
+
+	defer debug.SetMaxThreads(debug.SetMaxThreads(threads / 2))
+
+	var wg sync.WaitGroup
+	wg.Add(threads)
+	c := make(chan bool, threads)
+	for i := 0; i < threads; i++ {
+		go func(i int) {
+			defer wg.Done()
+			var b [1]byte
+			c <- true
+			if _, err := r[i].Read(b[:]); err != nil {
+				t.Error(err)
+			}
+		}(i)
+	}
+
+	for i := 0; i < threads; i++ {
+		<-c
+	}
+
+	// If we are still alive, it means that the 100 goroutines did
+	// not require 100 threads.
+
+	for i := 0; i < threads; i++ {
+		if _, err := w[i].Write([]byte{0}); err != nil {
+			t.Error(err)
+		}
+		if err := w[i].Close(); err != nil {
+			t.Error(err)
+		}
+	}
+
+	wg.Wait()
+
+	for i := 0; i < threads; i++ {
+		if err := r[i].Close(); err != nil {
+			t.Error(err)
+		}
+	}
+}
+
+func TestDoubleCloseError(t *testing.T) {
+	path := sfdir + "/" + sfname
+	file, err := Open(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := file.Close(); err != nil {
+		t.Fatalf("unexpected error from Close: %v", err)
+	}
+	if err := file.Close(); err == nil {
+		t.Error("second Close did not fail")
+	} else if pe, ok := err.(*PathError); !ok {
+		t.Errorf("second Close returned unexpected error type %T; expected os.PathError", pe)
+	} else if pe.Err != ErrClosed {
+		t.Errorf("second Close returned %q, wanted %q", err, ErrClosed)
+	} else {
+		t.Logf("second close returned expected error %q", err)
+	}
+}
diff --git a/libgo/go/os/pipe_bsd.go b/libgo/go/os/pipe_bsd.go
index ebe198b..ae153fa 100644
--- a/libgo/go/os/pipe_bsd.go
+++ b/libgo/go/os/pipe_bsd.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build aix darwin dragonfly freebsd nacl netbsd openbsd solaris
+// +build aix darwin dragonfly nacl netbsd openbsd solaris
 
 package os
 
@@ -24,5 +24,5 @@
 	syscall.CloseOnExec(p[1])
 	syscall.ForkLock.RUnlock()
 
-	return NewFile(uintptr(p[0]), "|0"), NewFile(uintptr(p[1]), "|1"), nil
+	return newFile(uintptr(p[0]), "|0", true), newFile(uintptr(p[1]), "|1", true), nil
 }
diff --git a/libgo/go/os/pipe_freebsd.go b/libgo/go/os/pipe_freebsd.go
new file mode 100644
index 0000000..ea6622c
--- /dev/null
+++ b/libgo/go/os/pipe_freebsd.go
@@ -0,0 +1,34 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package os
+
+import "syscall"
+
+// Pipe returns a connected pair of Files; reads from r return bytes written to w.
+// It returns the files and an error, if any.
+func Pipe() (r *File, w *File, err error) {
+	var p [2]int
+
+	e := syscall.Pipe2(p[0:], syscall.O_CLOEXEC)
+	if e != nil {
+		// Fallback support for FreeBSD 9, which lacks Pipe2.
+		//
+		// TODO: remove this for Go 1.10 when FreeBSD 9
+		// is removed (Issue 19072).
+
+		// See ../syscall/exec.go for description of lock.
+		syscall.ForkLock.RLock()
+		e := syscall.Pipe(p[0:])
+		if e != nil {
+			syscall.ForkLock.RUnlock()
+			return nil, nil, NewSyscallError("pipe", e)
+		}
+		syscall.CloseOnExec(p[0])
+		syscall.CloseOnExec(p[1])
+		syscall.ForkLock.RUnlock()
+	}
+
+	return newFile(uintptr(p[0]), "|0", true), newFile(uintptr(p[1]), "|1", true), nil
+}
diff --git a/libgo/go/os/pipe_linux.go b/libgo/go/os/pipe_linux.go
index 9bafad8..96f2ce9 100644
--- a/libgo/go/os/pipe_linux.go
+++ b/libgo/go/os/pipe_linux.go
@@ -29,5 +29,5 @@
 		return nil, nil, NewSyscallError("pipe2", e)
 	}
 
-	return NewFile(uintptr(p[0]), "|0"), NewFile(uintptr(p[1]), "|1"), nil
+	return newFile(uintptr(p[0]), "|0", true), newFile(uintptr(p[1]), "|1", true), nil
 }
diff --git a/libgo/go/os/pipe_test.go b/libgo/go/os/pipe_test.go
index 74cce80..9d79d84 100644
--- a/libgo/go/os/pipe_test.go
+++ b/libgo/go/os/pipe_test.go
@@ -10,11 +10,16 @@
 import (
 	"fmt"
 	"internal/testenv"
+	"io/ioutil"
 	"os"
 	osexec "os/exec"
 	"os/signal"
+	"runtime"
+	"strconv"
+	"strings"
 	"syscall"
 	"testing"
+	"time"
 )
 
 func TestEPIPE(t *testing.T) {
@@ -82,7 +87,7 @@
 					t.Errorf("unexpected SIGPIPE signal for descriptor %d sig %t", dest, sig)
 				}
 			} else {
-				t.Errorf("unexpected exit status %v for descriptor %ds sig %t", err, dest, sig)
+				t.Errorf("unexpected exit status %v for descriptor %d sig %t", err, dest, sig)
 			}
 		}
 	}
@@ -111,3 +116,107 @@
 	// For descriptor 3, a normal exit is expected.
 	os.Exit(0)
 }
+
+func testClosedPipeRace(t *testing.T, read bool) {
+	switch runtime.GOOS {
+	case "freebsd":
+		t.Skip("FreeBSD does not use the poller; issue 19093")
+	}
+
+	limit := 1
+	if !read {
+		// Get the amount we have to write to overload a pipe
+		// with no reader.
+		limit = 65537
+		if b, err := ioutil.ReadFile("/proc/sys/fs/pipe-max-size"); err == nil {
+			if i, err := strconv.Atoi(strings.TrimSpace(string(b))); err == nil {
+				limit = i + 1
+			}
+		}
+		t.Logf("using pipe write limit of %d", limit)
+	}
+
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer r.Close()
+	defer w.Close()
+
+	// Close the read end of the pipe in a goroutine while we are
+	// writing to the write end, or vice-versa.
+	go func() {
+		// Give the main goroutine a chance to enter the Read or
+		// Write call. This is sloppy but the test will pass even
+		// if we close before the read/write.
+		time.Sleep(20 * time.Millisecond)
+
+		var err error
+		if read {
+			err = r.Close()
+		} else {
+			err = w.Close()
+		}
+		if err != nil {
+			t.Error(err)
+		}
+	}()
+
+	b := make([]byte, limit)
+	if read {
+		_, err = r.Read(b[:])
+	} else {
+		_, err = w.Write(b[:])
+	}
+	if err == nil {
+		t.Error("I/O on closed pipe unexpectedly succeeded")
+	} else if pe, ok := err.(*os.PathError); !ok {
+		t.Errorf("I/O on closed pipe returned unexpected error type %T; expected os.PathError", pe)
+	} else if pe.Err != os.ErrClosed {
+		t.Errorf("got error %q but expected %q", pe.Err, os.ErrClosed)
+	} else {
+		t.Logf("I/O returned expected error %q", err)
+	}
+}
+
+func TestClosedPipeRaceRead(t *testing.T) {
+	testClosedPipeRace(t, true)
+}
+
+func TestClosedPipeRaceWrite(t *testing.T) {
+	testClosedPipeRace(t, false)
+}
+
+// Issue 20915: Reading on nonblocking fd should not return "waiting
+// for unsupported file type." Currently it returns EAGAIN; it is
+// possible that in the future it will simply wait for data.
+func TestReadNonblockingFd(t *testing.T) {
+	if os.Getenv("GO_WANT_READ_NONBLOCKING_FD") == "1" {
+		fd := int(os.Stdin.Fd())
+		syscall.SetNonblock(fd, true)
+		defer syscall.SetNonblock(fd, false)
+		_, err := os.Stdin.Read(make([]byte, 1))
+		if err != nil {
+			if perr, ok := err.(*os.PathError); !ok || perr.Err != syscall.EAGAIN {
+				t.Fatalf("read on nonblocking stdin got %q, should have gotten EAGAIN", err)
+			}
+		}
+		os.Exit(0)
+	}
+
+	testenv.MustHaveExec(t)
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer r.Close()
+	defer w.Close()
+	cmd := osexec.Command(os.Args[0], "-test.run="+t.Name())
+	cmd.Env = append(os.Environ(), "GO_WANT_READ_NONBLOCKING_FD=1")
+	cmd.Stdin = r
+	output, err := cmd.CombinedOutput()
+	t.Logf("%s", output)
+	if err != nil {
+		t.Errorf("child process failed: %v", err)
+	}
+}
diff --git a/libgo/go/os/proc.go b/libgo/go/os/proc.go
index 33a8b26..804128a 100644
--- a/libgo/go/os/proc.go
+++ b/libgo/go/os/proc.go
@@ -25,18 +25,29 @@
 func runtime_args() []string // in package runtime
 
 // Getuid returns the numeric user id of the caller.
+//
+// On Windows, it returns -1.
 func Getuid() int { return syscall.Getuid() }
 
 // Geteuid returns the numeric effective user id of the caller.
+//
+// On Windows, it returns -1.
 func Geteuid() int { return syscall.Geteuid() }
 
 // Getgid returns the numeric group id of the caller.
+//
+// On Windows, it returns -1.
 func Getgid() int { return syscall.Getgid() }
 
 // Getegid returns the numeric effective group id of the caller.
+//
+// On Windows, it returns -1.
 func Getegid() int { return syscall.Getegid() }
 
 // Getgroups returns a list of the numeric ids of groups that the caller belongs to.
+//
+// On Windows, it returns syscall.EWINDOWS. See the os/user package
+// for a possible alternative.
 func Getgroups() ([]int, error) {
 	gids, e := syscall.Getgroups()
 	return gids, NewSyscallError("getgroups", e)
diff --git a/libgo/go/os/signal/doc.go b/libgo/go/os/signal/doc.go
index 73b01a2..16f49c7 100644
--- a/libgo/go/os/signal/doc.go
+++ b/libgo/go/os/signal/doc.go
@@ -181,10 +181,11 @@
 SIGSETXID signals (which are used only on GNU/Linux), it will turn on
 the SA_ONSTACK flag and otherwise keep the signal handler.
 
-For the synchronous signals, the Go runtime will install a signal
-handler. It will save any existing signal handler. If a synchronous
-signal arrives while executing non-Go code, the Go runtime will invoke
-the existing signal handler instead of the Go signal handler.
+For the synchronous signals and SIGPIPE, the Go runtime will install a
+signal handler. It will save any existing signal handler. If a
+synchronous signal arrives while executing non-Go code, the Go runtime
+will invoke the existing signal handler instead of the Go signal
+handler.
 
 Go code built with -buildmode=c-archive or -buildmode=c-shared will
 not install any other signal handlers by default. If there is an
diff --git a/libgo/go/os/signal/signal.go b/libgo/go/os/signal/signal.go
index c1376da..e5a21e8 100644
--- a/libgo/go/os/signal/signal.go
+++ b/libgo/go/os/signal/signal.go
@@ -11,8 +11,21 @@
 
 var handlers struct {
 	sync.Mutex
-	m   map[chan<- os.Signal]*handler
+	// Map a channel to the signals that should be sent to it.
+	m map[chan<- os.Signal]*handler
+	// Map a signal to the number of channels receiving it.
 	ref [numSig]int64
+	// Map channels to signals while the channel is being stopped.
+	// Not a map because entries live here only very briefly.
+	// We need a separate container because we need m to correspond to ref
+	// at all times, and we also need to keep track of the *handler
+	// value for a channel being stopped. See the Stop function.
+	stopping []stopping
+}
+
+type stopping struct {
+	c chan<- os.Signal
+	h *handler
 }
 
 type handler struct {
@@ -142,10 +155,10 @@
 // When Stop returns, it is guaranteed that c will receive no more signals.
 func Stop(c chan<- os.Signal) {
 	handlers.Lock()
-	defer handlers.Unlock()
 
 	h := handlers.m[c]
 	if h == nil {
+		handlers.Unlock()
 		return
 	}
 	delete(handlers.m, c)
@@ -158,8 +171,40 @@
 			}
 		}
 	}
+
+	// Signals will no longer be delivered to the channel.
+	// We want to avoid a race for a signal such as SIGINT:
+	// it should be either delivered to the channel,
+	// or the program should take the default action (that is, exit).
+	// To avoid the possibility that the signal is delivered,
+	// and the signal handler invoked, and then Stop deregisters
+	// the channel before the process function below has a chance
+	// to send it on the channel, put the channel on a list of
+	// channels being stopped and wait for signal delivery to
+	// quiesce before fully removing it.
+
+	handlers.stopping = append(handlers.stopping, stopping{c, h})
+
+	handlers.Unlock()
+
+	signalWaitUntilIdle()
+
+	handlers.Lock()
+
+	for i, s := range handlers.stopping {
+		if s.c == c {
+			handlers.stopping = append(handlers.stopping[:i], handlers.stopping[i+1:]...)
+			break
+		}
+	}
+
+	handlers.Unlock()
 }
 
+// Wait until there are no more signals waiting to be delivered.
+// Defined by the runtime package.
+func signalWaitUntilIdle()
+
 func process(sig os.Signal) {
 	n := signum(sig)
 	if n < 0 {
@@ -178,4 +223,14 @@
 			}
 		}
 	}
+
+	// Avoid the race mentioned in Stop.
+	for _, d := range handlers.stopping {
+		if d.h.want(n) {
+			select {
+			case d.c <- sig:
+			default:
+			}
+		}
+	}
 }
diff --git a/libgo/go/os/signal/signal_test.go b/libgo/go/os/signal/signal_test.go
index c8409e7..10a4146 100644
--- a/libgo/go/os/signal/signal_test.go
+++ b/libgo/go/os/signal/signal_test.go
@@ -7,12 +7,16 @@
 package signal
 
 import (
+	"bytes"
 	"flag"
+	"fmt"
+	"internal/testenv"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"runtime"
 	"strconv"
+	"sync"
 	"syscall"
 	"testing"
 	"time"
@@ -301,3 +305,90 @@
 	syscall.Kill(syscall.Getpid(), syscall.SIGCONT)
 	waitSig(t, c, syscall.SIGCONT)
 }
+
+// Test race between stopping and receiving a signal (issue 14571).
+func TestAtomicStop(t *testing.T) {
+	if os.Getenv("GO_TEST_ATOMIC_STOP") != "" {
+		atomicStopTestProgram()
+		t.Fatal("atomicStopTestProgram returned")
+	}
+
+	testenv.MustHaveExec(t)
+
+	const execs = 10
+	for i := 0; i < execs; i++ {
+		cmd := exec.Command(os.Args[0], "-test.run=TestAtomicStop")
+		cmd.Env = append(os.Environ(), "GO_TEST_ATOMIC_STOP=1")
+		out, err := cmd.CombinedOutput()
+		if err == nil {
+			t.Logf("iteration %d: output %s", i, out)
+		} else {
+			t.Logf("iteration %d: exit status %q: output: %s", i, err, out)
+		}
+
+		lost := bytes.Contains(out, []byte("lost signal"))
+		if lost {
+			t.Errorf("iteration %d: lost signal", i)
+		}
+
+		// The program should either die due to SIGINT,
+		// or exit with success without printing "lost signal".
+		if err == nil {
+			if len(out) > 0 && !lost {
+				t.Errorf("iteration %d: unexpected output", i)
+			}
+		} else {
+			if ee, ok := err.(*exec.ExitError); !ok {
+				t.Errorf("iteration %d: error (%v) has type %T; expected exec.ExitError", i, err, err)
+			} else if ws, ok := ee.Sys().(syscall.WaitStatus); !ok {
+				t.Errorf("iteration %d: error.Sys (%v) has type %T; expected syscall.WaitStatus", i, ee.Sys(), ee.Sys())
+			} else if !ws.Signaled() || ws.Signal() != syscall.SIGINT {
+				t.Errorf("iteration %d: got exit status %v; expected SIGINT", i, ee)
+			}
+		}
+	}
+}
+
+// atomicStopTestProgram is run in a subprocess by TestAtomicStop.
+// It tries to trigger a signal delivery race. This function should
+// either catch a signal or die from it.
+func atomicStopTestProgram() {
+	const tries = 10
+	pid := syscall.Getpid()
+	printed := false
+	for i := 0; i < tries; i++ {
+		cs := make(chan os.Signal, 1)
+		Notify(cs, syscall.SIGINT)
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			Stop(cs)
+		}()
+
+		syscall.Kill(pid, syscall.SIGINT)
+
+		// At this point we should either die from SIGINT or
+		// get a notification on cs. If neither happens, we
+		// dropped the signal. Give it a second to deliver,
+		// which is far far longer than it should require.
+
+		select {
+		case <-cs:
+		case <-time.After(1 * time.Second):
+			if !printed {
+				fmt.Print("lost signal on iterations:")
+				printed = true
+			}
+			fmt.Printf(" %d", i)
+		}
+
+		wg.Wait()
+	}
+	if printed {
+		fmt.Print("\n")
+	}
+
+	os.Exit(0)
+}
diff --git a/libgo/go/os/stat_unix.go b/libgo/go/os/stat_unix.go
index 043aefe..7855fba 100644
--- a/libgo/go/os/stat_unix.go
+++ b/libgo/go/os/stat_unix.go
@@ -17,7 +17,7 @@
 		return nil, ErrInvalid
 	}
 	var fs fileStat
-	err := syscall.Fstat(f.fd, &fs.sys)
+	err := f.pfd.Fstat(&fs.sys)
 	if err != nil {
 		return nil, &PathError{"stat", f.name, err}
 	}
diff --git a/libgo/go/os/sys_darwin.go b/libgo/go/os/sys_darwin.go
index 7a8330a..11d678e 100644
--- a/libgo/go/os/sys_darwin.go
+++ b/libgo/go/os/sys_darwin.go
@@ -4,28 +4,8 @@
 
 package os
 
-import "syscall"
-
 // supportsCloseOnExec reports whether the platform supports the
 // O_CLOEXEC flag.
-var supportsCloseOnExec bool
-
-func init() {
-	// Seems like kern.osreldate is veiled on latest OS X. We use
-	// kern.osrelease instead.
-	osver, err := syscall.Sysctl("kern.osrelease")
-	if err != nil {
-		return
-	}
-	var i int
-	for i = range osver {
-		if osver[i] != '.' {
-			continue
-		}
-	}
-	// The O_CLOEXEC flag was introduced in OS X 10.7 (Darwin
-	// 11.0.0). See http://support.apple.com/kb/HT1633.
-	if i > 2 || i == 2 && osver[0] >= '1' && osver[1] >= '1' {
-		supportsCloseOnExec = true
-	}
-}
+// The O_CLOEXEC flag was introduced in OS X 10.7 (Darwin 11.0.0).
+// See http://support.apple.com/kb/HT1633.
+const supportsCloseOnExec = true
diff --git a/libgo/go/os/types.go b/libgo/go/os/types.go
index c565483..db78487 100644
--- a/libgo/go/os/types.go
+++ b/libgo/go/os/types.go
@@ -45,7 +45,7 @@
 	ModeDir        FileMode = 1 << (32 - 1 - iota) // d: is a directory
 	ModeAppend                                     // a: append-only
 	ModeExclusive                                  // l: exclusive use
-	ModeTemporary                                  // T: temporary file (not backed up)
+	ModeTemporary                                  // T: temporary file; Plan 9 only
 	ModeSymlink                                    // L: symbolic link
 	ModeDevice                                     // D: device file
 	ModeNamedPipe                                  // p: named pipe (FIFO)
diff --git a/libgo/go/os/types_unix.go b/libgo/go/os/types_unix.go
index 1f61481..c0259ae 100644
--- a/libgo/go/os/types_unix.go
+++ b/libgo/go/os/types_unix.go
@@ -29,5 +29,3 @@
 func sameFile(fs1, fs2 *fileStat) bool {
 	return fs1.sys.Dev == fs2.sys.Dev && fs1.sys.Ino == fs2.sys.Ino
 }
-
-const badFd = -1
diff --git a/libgo/go/os/types_windows.go b/libgo/go/os/types_windows.go
index ad4e863..01d6b62 100644
--- a/libgo/go/os/types_windows.go
+++ b/libgo/go/os/types_windows.go
@@ -12,16 +12,17 @@
 
 // A fileStat is the implementation of FileInfo returned by Stat and Lstat.
 type fileStat struct {
-	name string
-	sys  syscall.Win32FileAttributeData
-	pipe bool
+	name     string
+	sys      syscall.Win32FileAttributeData
+	filetype uint32 // what syscall.GetFileType returns
 
 	// used to implement SameFile
 	sync.Mutex
-	path  string
-	vol   uint32
-	idxhi uint32
-	idxlo uint32
+	path             string
+	vol              uint32
+	idxhi            uint32
+	idxlo            uint32
+	appendNameToPath bool
 }
 
 func (fs *fileStat) Size() int64 {
@@ -32,19 +33,22 @@
 	if fs == &devNullStat {
 		return ModeDevice | ModeCharDevice | 0666
 	}
-	if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
-		m |= ModeDir | 0111
-	}
 	if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_READONLY != 0 {
 		m |= 0444
 	} else {
 		m |= 0666
 	}
 	if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_REPARSE_POINT != 0 {
-		m |= ModeSymlink
+		return m | ModeSymlink
 	}
-	if fs.pipe {
+	if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
+		m |= ModeDir | 0111
+	}
+	switch fs.filetype {
+	case syscall.FILE_TYPE_PIPE:
 		m |= ModeNamedPipe
+	case syscall.FILE_TYPE_CHAR:
+		m |= ModeCharDevice
 	}
 	return m
 }
@@ -63,7 +67,13 @@
 		// already done
 		return nil
 	}
-	pathp, err := syscall.UTF16PtrFromString(fs.path)
+	var path string
+	if fs.appendNameToPath {
+		path = fs.path + `\` + fs.name
+	} else {
+		path = fs.path
+	}
+	pathp, err := syscall.UTF16PtrFromString(path)
 	if err != nil {
 		return err
 	}
diff --git a/libgo/go/os/user/cgo_lookup_unix.go b/libgo/go/os/user/cgo_lookup_unix.go
new file mode 100644
index 0000000..8881366
--- /dev/null
+++ b/libgo/go/os/user/cgo_lookup_unix.go
@@ -0,0 +1,266 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd !android,linux netbsd openbsd solaris
+// +build cgo
+
+package user
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+	"syscall"
+	"unsafe"
+)
+
+// bytePtrToString takes a NUL-terminated array of bytes and convert
+// it to a Go string.
+func bytePtrToString(p *byte) string {
+	a := (*[10000]byte)(unsafe.Pointer(p))
+	i := 0
+	for a[i] != 0 {
+		i++
+	}
+	return string(a[:i])
+}
+
+func current() (*User, error) {
+	return lookupUnixUid(syscall.Getuid())
+}
+
+func lookupUser(username string) (*User, error) {
+	var pwd syscall.Passwd
+	var result *syscall.Passwd
+	p := syscall.StringBytePtr(username)
+
+	buf := alloc(userBuffer)
+	defer buf.free()
+
+	err := retryWithBuffer(buf, func() syscall.Errno {
+		syscall.Entersyscall()
+		rv := libc_getpwnam_r(p,
+			&pwd,
+			buf.ptr,
+			buf.size,
+			&result)
+		syscall.Exitsyscall()
+		if rv != 0 {
+			return syscall.GetErrno()
+		}
+		return 0
+	})
+	if err != nil {
+		return nil, fmt.Errorf("user: lookup username %s: %v", username, err)
+	}
+	if result == nil {
+		return nil, UnknownUserError(username)
+	}
+	return buildUser(&pwd), err
+}
+
+func lookupUserId(uid string) (*User, error) {
+	i, e := strconv.Atoi(uid)
+	if e != nil {
+		return nil, e
+	}
+	return lookupUnixUid(i)
+}
+
+func lookupUnixUid(uid int) (*User, error) {
+	var pwd syscall.Passwd
+	var result *syscall.Passwd
+
+	buf := alloc(userBuffer)
+	defer buf.free()
+
+	err := retryWithBuffer(buf, func() syscall.Errno {
+		syscall.Entersyscall()
+		rv := libc_getpwuid_r(syscall.Uid_t(uid),
+			&pwd,
+			buf.ptr,
+			buf.size,
+			&result)
+		syscall.Exitsyscall()
+		if rv != 0 {
+			return syscall.GetErrno()
+		}
+		return 0
+	})
+	if err != nil {
+		return nil, fmt.Errorf("user: lookup userid %d: %v", uid, err)
+	}
+	if result == nil {
+		return nil, UnknownUserIdError(uid)
+	}
+	return buildUser(&pwd), nil
+}
+
+func buildUser(pwd *syscall.Passwd) *User {
+	u := &User{
+		Uid:      strconv.Itoa(int(pwd.Pw_uid)),
+		Gid:      strconv.Itoa(int(pwd.Pw_gid)),
+		Username: bytePtrToString((*byte)(unsafe.Pointer(pwd.Pw_name))),
+		Name:     bytePtrToString((*byte)(unsafe.Pointer(pwd.Pw_gecos))),
+		HomeDir:  bytePtrToString((*byte)(unsafe.Pointer(pwd.Pw_dir))),
+	}
+	// The pw_gecos field isn't quite standardized. Some docs
+	// say: "It is expected to be a comma separated list of
+	// personal data where the first item is the full name of the
+	// user."
+	if i := strings.Index(u.Name, ","); i >= 0 {
+		u.Name = u.Name[:i]
+	}
+	return u
+}
+
+func currentGroup() (*Group, error) {
+	return lookupUnixGid(syscall.Getgid())
+}
+
+func lookupGroup(groupname string) (*Group, error) {
+	var grp syscall.Group
+	var result *syscall.Group
+
+	buf := alloc(groupBuffer)
+	defer buf.free()
+	p := syscall.StringBytePtr(groupname)
+
+	err := retryWithBuffer(buf, func() syscall.Errno {
+		syscall.Entersyscall()
+		rv := libc_getgrnam_r(p,
+			&grp,
+			buf.ptr,
+			buf.size,
+			&result)
+		syscall.Exitsyscall()
+		if rv != 0 {
+			return syscall.GetErrno()
+		}
+		return 0
+	})
+	if err != nil {
+		return nil, fmt.Errorf("user: lookup groupname %s: %v", groupname, err)
+	}
+	if result == nil {
+		return nil, UnknownGroupError(groupname)
+	}
+	return buildGroup(&grp), nil
+}
+
+func lookupGroupId(gid string) (*Group, error) {
+	i, e := strconv.Atoi(gid)
+	if e != nil {
+		return nil, e
+	}
+	return lookupUnixGid(i)
+}
+
+func lookupUnixGid(gid int) (*Group, error) {
+	var grp syscall.Group
+	var result *syscall.Group
+
+	buf := alloc(groupBuffer)
+	defer buf.free()
+
+	err := retryWithBuffer(buf, func() syscall.Errno {
+		syscall.Entersyscall()
+		rv := libc_getgrgid_r(syscall.Gid_t(gid),
+			&grp,
+			buf.ptr,
+			buf.size,
+			&result)
+		syscall.Exitsyscall()
+		if rv != 0 {
+			return syscall.GetErrno()
+		}
+		return 0
+	})
+	if err != nil {
+		return nil, fmt.Errorf("user: lookup groupid %d: %v", gid, err)
+	}
+	if result == nil {
+		return nil, UnknownGroupIdError(strconv.Itoa(gid))
+	}
+	return buildGroup(&grp), nil
+}
+
+func buildGroup(grp *syscall.Group) *Group {
+	g := &Group{
+		Gid:  strconv.Itoa(int(grp.Gr_gid)),
+		Name: bytePtrToString((*byte)(unsafe.Pointer(grp.Gr_name))),
+	}
+	return g
+}
+
+type bufferKind int
+
+const (
+	userBuffer  = bufferKind(syscall.SC_GETPW_R_SIZE_MAX)
+	groupBuffer = bufferKind(syscall.SC_GETGR_R_SIZE_MAX)
+)
+
+func (k bufferKind) initialSize() syscall.Size_t {
+	sz, _ := syscall.Sysconf(int(k))
+	if sz == -1 {
+		// DragonFly and FreeBSD do not have _SC_GETPW_R_SIZE_MAX.
+		// Additionally, not all Linux systems have it, either. For
+		// example, the musl libc returns -1.
+		return 1024
+	}
+	if !isSizeReasonable(int64(sz)) {
+		// Truncate.  If this truly isn't enough, retryWithBuffer will error on the first run.
+		return maxBufferSize
+	}
+	return syscall.Size_t(sz)
+}
+
+type memBuffer struct {
+	ptr  *byte
+	size syscall.Size_t
+}
+
+func alloc(kind bufferKind) *memBuffer {
+	sz := kind.initialSize()
+	b := make([]byte, sz)
+	return &memBuffer{
+		ptr:  &b[0],
+		size: sz,
+	}
+}
+
+func (mb *memBuffer) resize(newSize syscall.Size_t) {
+	b := make([]byte, newSize)
+	mb.ptr = &b[0]
+	mb.size = newSize
+}
+
+func (mb *memBuffer) free() {
+	mb.ptr = nil
+}
+
+// retryWithBuffer repeatedly calls f(), increasing the size of the
+// buffer each time, until f succeeds, fails with a non-ERANGE error,
+// or the buffer exceeds a reasonable limit.
+func retryWithBuffer(buf *memBuffer, f func() syscall.Errno) error {
+	for {
+		errno := f()
+		if errno == 0 {
+			return nil
+		} else if errno != syscall.ERANGE {
+			return errno
+		}
+		newSize := buf.size * 2
+		if !isSizeReasonable(int64(newSize)) {
+			return fmt.Errorf("internal buffer exceeds %d bytes", maxBufferSize)
+		}
+		buf.resize(newSize)
+	}
+}
+
+const maxBufferSize = 1 << 20
+
+func isSizeReasonable(sz int64) bool {
+	return sz > 0 && sz <= maxBufferSize
+}
diff --git a/libgo/go/os/user/lookup.go b/libgo/go/os/user/lookup.go
index 3b4421b..2243a25 100644
--- a/libgo/go/os/user/lookup.go
+++ b/libgo/go/os/user/lookup.go
@@ -4,20 +4,40 @@
 
 package user
 
+import "sync"
+
 // Current returns the current user.
 func Current() (*User, error) {
-	return current()
+	cache.Do(func() { cache.u, cache.err = current() })
+	if cache.err != nil {
+		return nil, cache.err
+	}
+	u := *cache.u // copy
+	return &u, nil
+}
+
+// cache of the current user
+var cache struct {
+	sync.Once
+	u   *User
+	err error
 }
 
 // Lookup looks up a user by username. If the user cannot be found, the
 // returned error is of type UnknownUserError.
 func Lookup(username string) (*User, error) {
+	if u, err := Current(); err == nil && u.Username == username {
+		return u, err
+	}
 	return lookupUser(username)
 }
 
 // LookupId looks up a user by userid. If the user cannot be found, the
 // returned error is of type UnknownUserIdError.
 func LookupId(uid string) (*User, error) {
+	if u, err := Current(); err == nil && u.Uid == uid {
+		return u, err
+	}
 	return lookupUserId(uid)
 }
 
diff --git a/libgo/go/os/user/lookup_android.go b/libgo/go/os/user/lookup_android.go
index b1be3dc..8ca30b8 100644
--- a/libgo/go/os/user/lookup_android.go
+++ b/libgo/go/os/user/lookup_android.go
@@ -8,15 +8,6 @@
 
 import "errors"
 
-func init() {
-	userImplemented = false
-	groupImplemented = false
-}
-
-func current() (*User, error) {
-	return nil, errors.New("user: Current not implemented on android")
-}
-
 func lookupUser(string) (*User, error) {
 	return nil, errors.New("user: Lookup not implemented on android")
 }
@@ -32,7 +23,3 @@
 func lookupGroupId(string) (*Group, error) {
 	return nil, errors.New("user: LookupGroupId not implemented on android")
 }
-
-func listGroups(*User) ([]string, error) {
-	return nil, errors.New("user: GroupIds not implemented on android")
-}
diff --git a/libgo/go/os/user/lookup_stubs.go b/libgo/go/os/user/lookup_stubs.go
index ebf24f7..d23870f 100644
--- a/libgo/go/os/user/lookup_stubs.go
+++ b/libgo/go/os/user/lookup_stubs.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !cgo,!windows,!plan9,!android
+// +build !cgo,!windows,!plan9 android
 
 package user
 
@@ -15,7 +15,6 @@
 )
 
 func init() {
-	userImplemented = false
 	groupImplemented = false
 }
 
@@ -27,7 +26,9 @@
 		Name:     "", // ignored
 		HomeDir:  os.Getenv("HOME"),
 	}
-	if runtime.GOOS == "nacl" {
+	// On NaCL and Android, return a dummy user instead of failing.
+	switch runtime.GOOS {
+	case "nacl":
 		if u.Uid == "" {
 			u.Uid = "1"
 		}
@@ -35,7 +36,17 @@
 			u.Username = "nacl"
 		}
 		if u.HomeDir == "" {
-			u.HomeDir = "/home/nacl"
+			u.HomeDir = "/"
+		}
+	case "android":
+		if u.Uid == "" {
+			u.Uid = "1"
+		}
+		if u.Username == "" {
+			u.Username = "android"
+		}
+		if u.HomeDir == "" {
+			u.HomeDir = "/sdcard"
 		}
 	}
 	// cgo isn't available, but if we found the minimum information
@@ -46,23 +57,10 @@
 	return u, fmt.Errorf("user: Current not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
 }
 
-func lookupUser(username string) (*User, error) {
-	return nil, errors.New("user: Lookup requires cgo")
-}
-
-func lookupUserId(uid string) (*User, error) {
-	return nil, errors.New("user: LookupId requires cgo")
-}
-
-func lookupGroup(groupname string) (*Group, error) {
-	return nil, errors.New("user: LookupGroup requires cgo")
-}
-
-func lookupGroupId(string) (*Group, error) {
-	return nil, errors.New("user: LookupGroupId requires cgo")
-}
-
 func listGroups(*User) ([]string, error) {
+	if runtime.GOOS == "android" {
+		return nil, errors.New("user: GroupIds not implemented on Android")
+	}
 	return nil, errors.New("user: GroupIds requires cgo")
 }
 
diff --git a/libgo/go/os/user/lookup_unix.go b/libgo/go/os/user/lookup_unix.go
index 9670ada..5f34ba8 100644
--- a/libgo/go/os/user/lookup_unix.go
+++ b/libgo/go/os/user/lookup_unix.go
@@ -1,266 +1,197 @@
-// Copyright 2011 The Go Authors. All rights reserved.
+// Copyright 2016 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build aix darwin dragonfly freebsd !android,linux netbsd openbsd solaris
-// +build cgo
+// +build darwin dragonfly freebsd !android,linux nacl netbsd openbsd solaris
+// +build !cgo
 
 package user
 
 import (
-	"fmt"
+	"bufio"
+	"bytes"
+	"errors"
+	"io"
+	"os"
 	"strconv"
 	"strings"
-	"syscall"
-	"unsafe"
 )
 
-// bytePtrToString takes a NUL-terminated array of bytes and convert
-// it to a Go string.
-func bytePtrToString(p *byte) string {
-	a := (*[10000]byte)(unsafe.Pointer(p))
-	i := 0
-	for a[i] != 0 {
-		i++
-	}
-	return string(a[:i])
+const groupFile = "/etc/group"
+const userFile = "/etc/passwd"
+
+var colon = []byte{':'}
+
+func init() {
+	groupImplemented = false
 }
 
-func current() (*User, error) {
-	return lookupUnixUid(syscall.Getuid())
-}
+// lineFunc returns a value, an error, or (nil, nil) to skip the row.
+type lineFunc func(line []byte) (v interface{}, err error)
 
-func lookupUser(username string) (*User, error) {
-	var pwd syscall.Passwd
-	var result *syscall.Passwd
-	p := syscall.StringBytePtr(username)
-
-	buf := alloc(userBuffer)
-	defer buf.free()
-
-	err := retryWithBuffer(buf, func() syscall.Errno {
-		syscall.Entersyscall()
-		rv := libc_getpwnam_r(p,
-			&pwd,
-			buf.ptr,
-			buf.size,
-			&result)
-		syscall.Exitsyscall()
-		if rv != 0 {
-			return syscall.GetErrno()
+// readColonFile parses r as an /etc/group or /etc/passwd style file, running
+// fn for each row. readColonFile returns a value, an error, or (nil, nil) if
+// the end of the file is reached without a match.
+func readColonFile(r io.Reader, fn lineFunc) (v interface{}, err error) {
+	bs := bufio.NewScanner(r)
+	for bs.Scan() {
+		line := bs.Bytes()
+		// There's no spec for /etc/passwd or /etc/group, but we try to follow
+		// the same rules as the glibc parser, which allows comments and blank
+		// space at the beginning of a line.
+		line = bytes.TrimSpace(line)
+		if len(line) == 0 || line[0] == '#' {
+			continue
 		}
-		return 0
-	})
-	if err != nil {
-		return nil, fmt.Errorf("user: lookup username %s: %v", username, err)
+		v, err = fn(line)
+		if v != nil || err != nil {
+			return
+		}
 	}
-	if result == nil {
-		return nil, UnknownUserError(username)
-	}
-	return buildUser(&pwd), err
+	return nil, bs.Err()
 }
 
-func lookupUserId(uid string) (*User, error) {
+func matchGroupIndexValue(value string, idx int) lineFunc {
+	var leadColon string
+	if idx > 0 {
+		leadColon = ":"
+	}
+	substr := []byte(leadColon + value + ":")
+	return func(line []byte) (v interface{}, err error) {
+		if !bytes.Contains(line, substr) || bytes.Count(line, colon) < 3 {
+			return
+		}
+		// wheel:*:0:root
+		parts := strings.SplitN(string(line), ":", 4)
+		if len(parts) < 4 || parts[0] == "" || parts[idx] != value ||
+			// If the file contains +foo and you search for "foo", glibc
+			// returns an "invalid argument" error. Similarly, if you search
+			// for a gid for a row where the group name starts with "+" or "-",
+			// glibc fails to find the record.
+			parts[0][0] == '+' || parts[0][0] == '-' {
+			return
+		}
+		if _, err := strconv.Atoi(parts[2]); err != nil {
+			return nil, nil
+		}
+		return &Group{Name: parts[0], Gid: parts[2]}, nil
+	}
+}
+
+func findGroupId(id string, r io.Reader) (*Group, error) {
+	if v, err := readColonFile(r, matchGroupIndexValue(id, 2)); err != nil {
+		return nil, err
+	} else if v != nil {
+		return v.(*Group), nil
+	}
+	return nil, UnknownGroupIdError(id)
+}
+
+func findGroupName(name string, r io.Reader) (*Group, error) {
+	if v, err := readColonFile(r, matchGroupIndexValue(name, 0)); err != nil {
+		return nil, err
+	} else if v != nil {
+		return v.(*Group), nil
+	}
+	return nil, UnknownGroupError(name)
+}
+
+// returns a *User for a row if that row's has the given value at the
+// given index.
+func matchUserIndexValue(value string, idx int) lineFunc {
+	var leadColon string
+	if idx > 0 {
+		leadColon = ":"
+	}
+	substr := []byte(leadColon + value + ":")
+	return func(line []byte) (v interface{}, err error) {
+		if !bytes.Contains(line, substr) || bytes.Count(line, colon) < 6 {
+			return
+		}
+		// kevin:x:1005:1006::/home/kevin:/usr/bin/zsh
+		parts := strings.SplitN(string(line), ":", 7)
+		if len(parts) < 6 || parts[idx] != value || parts[0] == "" ||
+			parts[0][0] == '+' || parts[0][0] == '-' {
+			return
+		}
+		if _, err := strconv.Atoi(parts[2]); err != nil {
+			return nil, nil
+		}
+		if _, err := strconv.Atoi(parts[3]); err != nil {
+			return nil, nil
+		}
+		u := &User{
+			Username: parts[0],
+			Uid:      parts[2],
+			Gid:      parts[3],
+			Name:     parts[4],
+			HomeDir:  parts[5],
+		}
+		// The pw_gecos field isn't quite standardized. Some docs
+		// say: "It is expected to be a comma separated list of
+		// personal data where the first item is the full name of the
+		// user."
+		if i := strings.Index(u.Name, ","); i >= 0 {
+			u.Name = u.Name[:i]
+		}
+		return u, nil
+	}
+}
+
+func findUserId(uid string, r io.Reader) (*User, error) {
 	i, e := strconv.Atoi(uid)
 	if e != nil {
-		return nil, e
+		return nil, errors.New("user: invalid userid " + uid)
 	}
-	return lookupUnixUid(i)
+	if v, err := readColonFile(r, matchUserIndexValue(uid, 2)); err != nil {
+		return nil, err
+	} else if v != nil {
+		return v.(*User), nil
+	}
+	return nil, UnknownUserIdError(i)
 }
 
-func lookupUnixUid(uid int) (*User, error) {
-	var pwd syscall.Passwd
-	var result *syscall.Passwd
-
-	buf := alloc(userBuffer)
-	defer buf.free()
-
-	err := retryWithBuffer(buf, func() syscall.Errno {
-		syscall.Entersyscall()
-		rv := libc_getpwuid_r(syscall.Uid_t(uid),
-			&pwd,
-			buf.ptr,
-			buf.size,
-			&result)
-		syscall.Exitsyscall()
-		if rv != 0 {
-			return syscall.GetErrno()
-		}
-		return 0
-	})
-	if err != nil {
-		return nil, fmt.Errorf("user: lookup userid %d: %v", uid, err)
+func findUsername(name string, r io.Reader) (*User, error) {
+	if v, err := readColonFile(r, matchUserIndexValue(name, 0)); err != nil {
+		return nil, err
+	} else if v != nil {
+		return v.(*User), nil
 	}
-	if result == nil {
-		return nil, UnknownUserIdError(uid)
-	}
-	return buildUser(&pwd), nil
-}
-
-func buildUser(pwd *syscall.Passwd) *User {
-	u := &User{
-		Uid:      strconv.Itoa(int(pwd.Pw_uid)),
-		Gid:      strconv.Itoa(int(pwd.Pw_gid)),
-		Username: bytePtrToString((*byte)(unsafe.Pointer(pwd.Pw_name))),
-		Name:     bytePtrToString((*byte)(unsafe.Pointer(pwd.Pw_gecos))),
-		HomeDir:  bytePtrToString((*byte)(unsafe.Pointer(pwd.Pw_dir))),
-	}
-	// The pw_gecos field isn't quite standardized. Some docs
-	// say: "It is expected to be a comma separated list of
-	// personal data where the first item is the full name of the
-	// user."
-	if i := strings.Index(u.Name, ","); i >= 0 {
-		u.Name = u.Name[:i]
-	}
-	return u
-}
-
-func currentGroup() (*Group, error) {
-	return lookupUnixGid(syscall.Getgid())
+	return nil, UnknownUserError(name)
 }
 
 func lookupGroup(groupname string) (*Group, error) {
-	var grp syscall.Group
-	var result *syscall.Group
-
-	buf := alloc(groupBuffer)
-	defer buf.free()
-	p := syscall.StringBytePtr(groupname)
-
-	err := retryWithBuffer(buf, func() syscall.Errno {
-		syscall.Entersyscall()
-		rv := libc_getgrnam_r(p,
-			&grp,
-			buf.ptr,
-			buf.size,
-			&result)
-		syscall.Exitsyscall()
-		if rv != 0 {
-			return syscall.GetErrno()
-		}
-		return 0
-	})
+	f, err := os.Open(groupFile)
 	if err != nil {
-		return nil, fmt.Errorf("user: lookup groupname %s: %v", groupname, err)
+		return nil, err
 	}
-	if result == nil {
-		return nil, UnknownGroupError(groupname)
-	}
-	return buildGroup(&grp), nil
+	defer f.Close()
+	return findGroupName(groupname, f)
 }
 
-func lookupGroupId(gid string) (*Group, error) {
-	i, e := strconv.Atoi(gid)
-	if e != nil {
-		return nil, e
-	}
-	return lookupUnixGid(i)
-}
-
-func lookupUnixGid(gid int) (*Group, error) {
-	var grp syscall.Group
-	var result *syscall.Group
-
-	buf := alloc(groupBuffer)
-	defer buf.free()
-
-	err := retryWithBuffer(buf, func() syscall.Errno {
-		syscall.Entersyscall()
-		rv := libc_getgrgid_r(syscall.Gid_t(gid),
-			&grp,
-			buf.ptr,
-			buf.size,
-			&result)
-		syscall.Exitsyscall()
-		if rv != 0 {
-			return syscall.GetErrno()
-		}
-		return 0
-	})
+func lookupGroupId(id string) (*Group, error) {
+	f, err := os.Open(groupFile)
 	if err != nil {
-		return nil, fmt.Errorf("user: lookup groupid %d: %v", gid, err)
+		return nil, err
 	}
-	if result == nil {
-		return nil, UnknownGroupIdError(strconv.Itoa(gid))
+	defer f.Close()
+	return findGroupId(id, f)
+}
+
+func lookupUser(username string) (*User, error) {
+	f, err := os.Open(userFile)
+	if err != nil {
+		return nil, err
 	}
-	return buildGroup(&grp), nil
+	defer f.Close()
+	return findUsername(username, f)
 }
 
-func buildGroup(grp *syscall.Group) *Group {
-	g := &Group{
-		Gid:  strconv.Itoa(int(grp.Gr_gid)),
-		Name: bytePtrToString((*byte)(unsafe.Pointer(grp.Gr_name))),
+func lookupUserId(uid string) (*User, error) {
+	f, err := os.Open(userFile)
+	if err != nil {
+		return nil, err
 	}
-	return g
-}
-
-type bufferKind int
-
-const (
-	userBuffer  = bufferKind(syscall.SC_GETPW_R_SIZE_MAX)
-	groupBuffer = bufferKind(syscall.SC_GETGR_R_SIZE_MAX)
-)
-
-func (k bufferKind) initialSize() syscall.Size_t {
-	sz, _ := syscall.Sysconf(int(k))
-	if sz == -1 {
-		// DragonFly and FreeBSD do not have _SC_GETPW_R_SIZE_MAX.
-		// Additionally, not all Linux systems have it, either. For
-		// example, the musl libc returns -1.
-		return 1024
-	}
-	if !isSizeReasonable(int64(sz)) {
-		// Truncate.  If this truly isn't enough, retryWithBuffer will error on the first run.
-		return maxBufferSize
-	}
-	return syscall.Size_t(sz)
-}
-
-type memBuffer struct {
-	ptr  *byte
-	size syscall.Size_t
-}
-
-func alloc(kind bufferKind) *memBuffer {
-	sz := kind.initialSize()
-	b := make([]byte, sz)
-	return &memBuffer{
-		ptr:  &b[0],
-		size: sz,
-	}
-}
-
-func (mb *memBuffer) resize(newSize syscall.Size_t) {
-	b := make([]byte, newSize)
-	mb.ptr = &b[0]
-	mb.size = newSize
-}
-
-func (mb *memBuffer) free() {
-	mb.ptr = nil
-}
-
-// retryWithBuffer repeatedly calls f(), increasing the size of the
-// buffer each time, until f succeeds, fails with a non-ERANGE error,
-// or the buffer exceeds a reasonable limit.
-func retryWithBuffer(buf *memBuffer, f func() syscall.Errno) error {
-	for {
-		errno := f()
-		if errno == 0 {
-			return nil
-		} else if errno != syscall.ERANGE {
-			return errno
-		}
-		newSize := buf.size * 2
-		if !isSizeReasonable(int64(newSize)) {
-			return fmt.Errorf("internal buffer exceeds %d bytes", maxBufferSize)
-		}
-		buf.resize(newSize)
-	}
-}
-
-const maxBufferSize = 1 << 20
-
-func isSizeReasonable(sz int64) bool {
-	return sz > 0 && sz <= maxBufferSize
+	defer f.Close()
+	return findUserId(uid, f)
 }
diff --git a/libgo/go/os/user/lookup_unix_test.go b/libgo/go/os/user/lookup_unix_test.go
new file mode 100644
index 0000000..02c88ab
--- /dev/null
+++ b/libgo/go/os/user/lookup_unix_test.go
@@ -0,0 +1,276 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd !android,linux nacl netbsd openbsd solaris
+// +build !cgo
+
+package user
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+const testGroupFile = `# See the opendirectoryd(8) man page for additional 
+# information about Open Directory.
+##
+nobody:*:-2:
+nogroup:*:-1:
+wheel:*:0:root
+emptyid:*::root
+invalidgid:*:notanumber:root
++plussign:*:20:root
+-minussign:*:21:root
+      
+daemon:*:1:root
+    indented:*:7:
+# comment:*:4:found
+     # comment:*:4:found
+kmem:*:2:root
+`
+
+var groupTests = []struct {
+	in   string
+	name string
+	gid  string
+}{
+	{testGroupFile, "nobody", "-2"},
+	{testGroupFile, "kmem", "2"},
+	{testGroupFile, "notinthefile", ""},
+	{testGroupFile, "comment", ""},
+	{testGroupFile, "plussign", ""},
+	{testGroupFile, "+plussign", ""},
+	{testGroupFile, "-minussign", ""},
+	{testGroupFile, "minussign", ""},
+	{testGroupFile, "emptyid", ""},
+	{testGroupFile, "invalidgid", ""},
+	{testGroupFile, "indented", "7"},
+	{testGroupFile, "# comment", ""},
+	{"", "emptyfile", ""},
+}
+
+func TestFindGroupName(t *testing.T) {
+	for _, tt := range groupTests {
+		got, err := findGroupName(tt.name, strings.NewReader(tt.in))
+		if tt.gid == "" {
+			if err == nil {
+				t.Errorf("findGroupName(%s): got nil error, expected err", tt.name)
+				continue
+			}
+			switch terr := err.(type) {
+			case UnknownGroupError:
+				if terr.Error() != "group: unknown group "+tt.name {
+					t.Errorf("findGroupName(%s): got %v, want %v", tt.name, terr, tt.name)
+				}
+			default:
+				t.Errorf("findGroupName(%s): got unexpected error %v", tt.name, terr)
+			}
+		} else {
+			if err != nil {
+				t.Fatalf("findGroupName(%s): got unexpected error %v", tt.name, err)
+			}
+			if got.Gid != tt.gid {
+				t.Errorf("findGroupName(%s): got gid %v, want %s", tt.name, got.Gid, tt.gid)
+			}
+			if got.Name != tt.name {
+				t.Errorf("findGroupName(%s): got name %s, want %s", tt.name, got.Name, tt.name)
+			}
+		}
+	}
+}
+
+var groupIdTests = []struct {
+	in   string
+	gid  string
+	name string
+}{
+	{testGroupFile, "-2", "nobody"},
+	{testGroupFile, "2", "kmem"},
+	{testGroupFile, "notinthefile", ""},
+	{testGroupFile, "comment", ""},
+	{testGroupFile, "7", "indented"},
+	{testGroupFile, "4", ""},
+	{testGroupFile, "20", ""}, // row starts with a plus
+	{testGroupFile, "21", ""}, // row starts with a minus
+	{"", "emptyfile", ""},
+}
+
+func TestFindGroupId(t *testing.T) {
+	for _, tt := range groupIdTests {
+		got, err := findGroupId(tt.gid, strings.NewReader(tt.in))
+		if tt.name == "" {
+			if err == nil {
+				t.Errorf("findGroupId(%s): got nil error, expected err", tt.gid)
+				continue
+			}
+			switch terr := err.(type) {
+			case UnknownGroupIdError:
+				if terr.Error() != "group: unknown groupid "+tt.gid {
+					t.Errorf("findGroupId(%s): got %v, want %v", tt.name, terr, tt.name)
+				}
+			default:
+				t.Errorf("findGroupId(%s): got unexpected error %v", tt.name, terr)
+			}
+		} else {
+			if err != nil {
+				t.Fatalf("findGroupId(%s): got unexpected error %v", tt.name, err)
+			}
+			if got.Gid != tt.gid {
+				t.Errorf("findGroupId(%s): got gid %v, want %s", tt.name, got.Gid, tt.gid)
+			}
+			if got.Name != tt.name {
+				t.Errorf("findGroupId(%s): got name %s, want %s", tt.name, got.Name, tt.name)
+			}
+		}
+	}
+}
+
+const testUserFile = `   # Example user file
+root:x:0:0:root:/root:/bin/bash
+daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
+bin:x:2:3:bin:/bin:/usr/sbin/nologin
+     indented:x:3:3:indented:/dev:/usr/sbin/nologin
+sync:x:4:65534:sync:/bin:/bin/sync
+negative:x:-5:60:games:/usr/games:/usr/sbin/nologin
+man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
+allfields:x:6:12:mansplit,man2,man3,man4:/home/allfields:/usr/sbin/nologin
++plussign:x:8:10:man:/var/cache/man:/usr/sbin/nologin
+-minussign:x:9:10:man:/var/cache/man:/usr/sbin/nologin
+
+malformed:x:27:12 # more:colons:after:comment
+
+struid:x:notanumber:12 # more:colons:after:comment
+
+# commented:x:28:12:commented:/var/cache/man:/usr/sbin/nologin
+      # commentindented:x:29:12:commentindented:/var/cache/man:/usr/sbin/nologin
+
+struid2:x:30:badgid:struid2name:/home/struid:/usr/sbin/nologin
+`
+
+var userIdTests = []struct {
+	in   string
+	uid  string
+	name string
+}{
+	{testUserFile, "-5", "negative"},
+	{testUserFile, "2", "bin"},
+	{testUserFile, "100", ""}, // not in the file
+	{testUserFile, "8", ""},   // plus sign, glibc doesn't find it
+	{testUserFile, "9", ""},   // minus sign, glibc doesn't find it
+	{testUserFile, "27", ""},  // malformed
+	{testUserFile, "28", ""},  // commented out
+	{testUserFile, "29", ""},  // commented out, indented
+	{testUserFile, "3", "indented"},
+	{testUserFile, "30", ""}, // the Gid is not valid, shouldn't match
+	{"", "1", ""},
+}
+
+func TestInvalidUserId(t *testing.T) {
+	_, err := findUserId("notanumber", strings.NewReader(""))
+	if err == nil {
+		t.Fatalf("findUserId('notanumber'): got nil error")
+	}
+	if want := "user: invalid userid notanumber"; err.Error() != want {
+		t.Errorf("findUserId('notanumber'): got %v, want %s", err, want)
+	}
+}
+
+func TestLookupUserId(t *testing.T) {
+	for _, tt := range userIdTests {
+		got, err := findUserId(tt.uid, strings.NewReader(tt.in))
+		if tt.name == "" {
+			if err == nil {
+				t.Errorf("findUserId(%s): got nil error, expected err", tt.uid)
+				continue
+			}
+			switch terr := err.(type) {
+			case UnknownUserIdError:
+				if want := "user: unknown userid " + tt.uid; terr.Error() != want {
+					t.Errorf("findUserId(%s): got %v, want %v", tt.name, terr, want)
+				}
+			default:
+				t.Errorf("findUserId(%s): got unexpected error %v", tt.name, terr)
+			}
+		} else {
+			if err != nil {
+				t.Fatalf("findUserId(%s): got unexpected error %v", tt.name, err)
+			}
+			if got.Uid != tt.uid {
+				t.Errorf("findUserId(%s): got uid %v, want %s", tt.name, got.Uid, tt.uid)
+			}
+			if got.Username != tt.name {
+				t.Errorf("findUserId(%s): got name %s, want %s", tt.name, got.Username, tt.name)
+			}
+		}
+	}
+}
+
+func TestLookupUserPopulatesAllFields(t *testing.T) {
+	u, err := findUsername("allfields", strings.NewReader(testUserFile))
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := &User{
+		Username: "allfields",
+		Uid:      "6",
+		Gid:      "12",
+		Name:     "mansplit",
+		HomeDir:  "/home/allfields",
+	}
+	if !reflect.DeepEqual(u, want) {
+		t.Errorf("findUsername: got %#v, want %#v", u, want)
+	}
+}
+
+var userTests = []struct {
+	in   string
+	name string
+	uid  string
+}{
+	{testUserFile, "negative", "-5"},
+	{testUserFile, "bin", "2"},
+	{testUserFile, "notinthefile", ""},
+	{testUserFile, "indented", "3"},
+	{testUserFile, "plussign", ""},
+	{testUserFile, "+plussign", ""},
+	{testUserFile, "minussign", ""},
+	{testUserFile, "-minussign", ""},
+	{testUserFile, "   indented", ""},
+	{testUserFile, "commented", ""},
+	{testUserFile, "commentindented", ""},
+	{testUserFile, "malformed", ""},
+	{testUserFile, "# commented", ""},
+	{"", "emptyfile", ""},
+}
+
+func TestLookupUser(t *testing.T) {
+	for _, tt := range userTests {
+		got, err := findUsername(tt.name, strings.NewReader(tt.in))
+		if tt.uid == "" {
+			if err == nil {
+				t.Errorf("lookupUser(%s): got nil error, expected err", tt.uid)
+				continue
+			}
+			switch terr := err.(type) {
+			case UnknownUserError:
+				if want := "user: unknown user " + tt.name; terr.Error() != want {
+					t.Errorf("lookupUser(%s): got %v, want %v", tt.name, terr, want)
+				}
+			default:
+				t.Errorf("lookupUser(%s): got unexpected error %v", tt.name, terr)
+			}
+		} else {
+			if err != nil {
+				t.Fatalf("lookupUser(%s): got unexpected error %v", tt.name, err)
+			}
+			if got.Uid != tt.uid {
+				t.Errorf("lookupUser(%s): got uid %v, want %s", tt.name, got.Uid, tt.uid)
+			}
+			if got.Username != tt.name {
+				t.Errorf("lookupUser(%s): got name %s, want %s", tt.name, got.Username, tt.name)
+			}
+		}
+	}
+}
diff --git a/libgo/go/os/user/user_test.go b/libgo/go/os/user/user_test.go
index 9d8d94d..b3aeed8 100644
--- a/libgo/go/os/user/user_test.go
+++ b/libgo/go/os/user/user_test.go
@@ -16,9 +16,6 @@
 }
 
 func TestCurrent(t *testing.T) {
-	if runtime.GOOS == "android" {
-		t.Skipf("skipping on %s", runtime.GOOS)
-	}
 	u, err := Current()
 	if err != nil {
 		t.Fatalf("Current: %v (got %#v)", err, u)
@@ -31,6 +28,12 @@
 	}
 }
 
+func BenchmarkCurrent(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Current()
+	}
+}
+
 func compare(t *testing.T, want, got *User) {
 	if want.Uid != got.Uid {
 		t.Errorf("got Uid=%q; want %q", got.Uid, want.Uid)
@@ -64,6 +67,9 @@
 	if err != nil {
 		t.Fatalf("Current: %v", err)
 	}
+	// TODO: Lookup() has a fast path that calls Current() and returns if the
+	// usernames match, so this test does not exercise very much. It would be
+	// good to try and test finding a different user than the current user.
 	got, err := Lookup(want.Username)
 	if err != nil {
 		t.Fatalf("Lookup: %v", err)
diff --git a/libgo/go/os/wait_unimp.go b/libgo/go/os/wait_unimp.go
index 0378b83..98243b5 100644
--- a/libgo/go/os/wait_unimp.go
+++ b/libgo/go/os/wait_unimp.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build aix dragonfly nacl netbsd openbsd solaris
+// +build aix darwin dragonfly nacl netbsd openbsd solaris
 
 package os
 
diff --git a/libgo/go/os/wait_waitid.go b/libgo/go/os/wait_waitid.go
index 3337395..5a62b27 100644
--- a/libgo/go/os/wait_waitid.go
+++ b/libgo/go/os/wait_waitid.go
@@ -2,7 +2,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// We used to used this code for Darwin, but according to issue #19314
+// waitid returns if the process is stopped, even when using WEXITED.
+
+// +build linux
 
 package os
 
diff --git a/libgo/go/path/example_test.go b/libgo/go/path/example_test.go
index 88b7655..21ed1fb 100644
--- a/libgo/go/path/example_test.go
+++ b/libgo/go/path/example_test.go
@@ -13,7 +13,12 @@
 
 func ExampleBase() {
 	fmt.Println(path.Base("/a/b"))
-	// Output: b
+	fmt.Println(path.Base("/"))
+	fmt.Println(path.Base(""))
+	// Output:
+	// b
+	// /
+	// .
 }
 
 func ExampleClean() {
@@ -24,6 +29,7 @@
 		"a/c/b/..",
 		"/../a/c",
 		"/../a/b/../././/c",
+		"",
 	}
 
 	for _, p := range paths {
@@ -37,16 +43,29 @@
 	// Clean("a/c/b/..") = "a/c"
 	// Clean("/../a/c") = "/a/c"
 	// Clean("/../a/b/../././/c") = "/a/c"
+	// Clean("") = "."
 }
 
 func ExampleDir() {
 	fmt.Println(path.Dir("/a/b/c"))
-	// Output: /a/b
+	fmt.Println(path.Dir("a/b/c"))
+	fmt.Println(path.Dir("/"))
+	fmt.Println(path.Dir(""))
+	// Output:
+	// /a/b
+	// a/b
+	// /
+	// .
 }
 
 func ExampleExt() {
 	fmt.Println(path.Ext("/a/b/c/bar.css"))
-	// Output: .css
+	fmt.Println(path.Ext("/"))
+	fmt.Println(path.Ext(""))
+	// Output:
+	// .css
+	//
+	//
 }
 
 func ExampleIsAbs() {
@@ -58,17 +77,26 @@
 	fmt.Println(path.Join("a", "b", "c"))
 	fmt.Println(path.Join("a", "b/c"))
 	fmt.Println(path.Join("a/b", "c"))
-	fmt.Println(path.Join("a/b", "/c"))
+	fmt.Println(path.Join("", ""))
+	fmt.Println(path.Join("a", ""))
+	fmt.Println(path.Join("", "a"))
 	// Output:
 	// a/b/c
 	// a/b/c
 	// a/b/c
-	// a/b/c
+	//
+	// a
+	// a
 }
 
 func ExampleSplit() {
 	fmt.Println(path.Split("static/myfile.css"))
-	// Output: static/ myfile.css
+	fmt.Println(path.Split("myfile.css"))
+	fmt.Println(path.Split(""))
+	// Output:
+	// static/ myfile.css
+	//  myfile.css
+	//
 }
 
 */
diff --git a/libgo/go/path/filepath/match_test.go b/libgo/go/path/filepath/match_test.go
index ae7ca1c..12d922f 100644
--- a/libgo/go/path/filepath/match_test.go
+++ b/libgo/go/path/filepath/match_test.go
@@ -155,8 +155,8 @@
 }
 
 func TestGlobError(t *testing.T) {
-	_, err := Glob("[7]")
-	if err != nil {
+	_, err := Glob("[]")
+	if err == nil {
 		t.Error("expected error for bad pattern; got none")
 	}
 }
diff --git a/libgo/go/path/filepath/path.go b/libgo/go/path/filepath/path.go
index 1d8e35c..c242143 100644
--- a/libgo/go/path/filepath/path.go
+++ b/libgo/go/path/filepath/path.go
@@ -4,6 +4,11 @@
 
 // Package filepath implements utility routines for manipulating filename paths
 // in a way compatible with the target operating system-defined file paths.
+//
+// The filepath package uses either forward slashes or backslashes,
+// depending on the operating system. To process paths such as URLs
+// that always use forward slashes regardless of the operating
+// system, see the path package.
 package filepath
 
 import (
@@ -461,6 +466,10 @@
 		i--
 	}
 	dir := Clean(path[len(vol) : i+1])
+	if dir == "." && len(vol) > 2 {
+		// must be UNC
+		return vol
+	}
 	return vol + dir
 }
 
diff --git a/libgo/go/path/filepath/path_test.go b/libgo/go/path/filepath/path_test.go
index 7389ea2..f2e9252 100644
--- a/libgo/go/path/filepath/path_test.go
+++ b/libgo/go/path/filepath/path_test.go
@@ -6,12 +6,14 @@
 
 import (
 	"errors"
+	"fmt"
 	"internal/testenv"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"reflect"
 	"runtime"
+	"sort"
 	"strings"
 	"testing"
 )
@@ -389,7 +391,7 @@
 // Assumes that each node name is unique. Good enough for a test.
 // If clear is true, any incoming error is cleared before return. The errors
 // are always accumulated, though.
-func mark(path string, info os.FileInfo, err error, errors *[]error, clear bool) error {
+func mark(info os.FileInfo, err error, errors *[]error, clear bool) error {
 	if err != nil {
 		*errors = append(*errors, err)
 		if clear {
@@ -438,7 +440,7 @@
 	errors := make([]error, 0, 10)
 	clear := true
 	markFn := func(path string, info os.FileInfo, err error) error {
-		return mark(path, info, err, &errors, clear)
+		return mark(info, err, &errors, clear)
 	}
 	// Expect no errors.
 	err := filepath.Walk(tree.name, markFn)
@@ -668,6 +670,7 @@
 	{`c:\a\b`, `c:\a`},
 	{`c:a\b`, `c:a`},
 	{`c:a\b\c`, `c:a\b`},
+	{`\\host\share`, `\\host\share`},
 	{`\\host\share\`, `\\host\share\`},
 	{`\\host\share\a`, `\\host\share\`},
 	{`\\host\share\a\b`, `\\host\share\a`},
@@ -1330,3 +1333,53 @@
 		t.Fatalf("%q not seen", ken)
 	}
 }
+
+func testWalkSymlink(t *testing.T, mklink func(target, link string) error) {
+	tmpdir, err := ioutil.TempDir("", "testWalkSymlink")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(tmpdir)
+
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Chdir(wd)
+
+	err = os.Chdir(tmpdir)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = mklink(tmpdir, "link")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var visited []string
+	err = filepath.Walk(tmpdir, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			t.Fatal(err)
+		}
+		rel, err := filepath.Rel(tmpdir, path)
+		if err != nil {
+			t.Fatal(err)
+		}
+		visited = append(visited, rel)
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	sort.Strings(visited)
+	want := []string{".", "link"}
+	if fmt.Sprintf("%q", visited) != fmt.Sprintf("%q", want) {
+		t.Errorf("unexpected paths visited %q, want %q", visited, want)
+	}
+}
+
+func TestWalkSymlink(t *testing.T) {
+	testenv.MustHaveSymlink(t)
+	testWalkSymlink(t, os.Symlink)
+}
diff --git a/libgo/go/path/path.go b/libgo/go/path/path.go
index 76c7814..5c90511 100644
--- a/libgo/go/path/path.go
+++ b/libgo/go/path/path.go
@@ -5,7 +5,10 @@
 // Package path implements utility routines for manipulating slash-separated
 // paths.
 //
-// To manipulate operating system paths, use the path/filepath package.
+// The path package should only be used for paths separated by forward
+// slashes, such as the paths in URLs. This package does not deal with
+// Windows paths with drive letters or backslashes; to manipulate
+// operating system paths, use the path/filepath package.
 package path
 
 import (
diff --git a/libgo/go/plugin/plugin.go b/libgo/go/plugin/plugin.go
index b86099a..c774465 100644
--- a/libgo/go/plugin/plugin.go
+++ b/libgo/go/plugin/plugin.go
@@ -4,8 +4,6 @@
 
 // Package plugin implements loading and symbol resolution of Go plugins.
 //
-// Currently plugins only work on Linux.
-//
 // A plugin is a Go main package with exported functions and variables that
 // has been built with:
 //
@@ -14,6 +12,9 @@
 // When a plugin is first opened, the init functions of all packages not
 // already part of the program are called. The main function is not run.
 // A plugin is only initialized once, and cannot be closed.
+//
+// The plugin support is currently incomplete, only supports Linux,
+// and has known bugs. Please report any issues.
 package plugin
 
 // Plugin is a loaded Go plugin.
@@ -44,9 +45,6 @@
 //
 //	package main
 //
-//	// // No C code needed.
-//	import "C"
-//
 //	import "fmt"
 //
 //	var V int
diff --git a/libgo/go/plugin/plugin_dlopen.go b/libgo/go/plugin/plugin_dlopen.go
index c5b0a47..3237598 100644
--- a/libgo/go/plugin/plugin_dlopen.go
+++ b/libgo/go/plugin/plugin_dlopen.go
@@ -39,6 +39,47 @@
 	"unsafe"
 )
 
+// avoid a dependency on strings
+func lastIndexByte(s string, c byte) int {
+	for i := len(s) - 1; i >= 0; i-- {
+		if s[i] == c {
+			return i
+		}
+	}
+	return -1
+}
+
+// pathToPrefix converts raw string to the prefix that will be used in the symbol
+// table. If modifying, modify the version in internal/obj/sym.go as well.
+func pathToPrefix(s string) string {
+	slash := lastIndexByte(s, '/')
+	// check for chars that need escaping
+	n := 0
+	for r := 0; r < len(s); r++ {
+		if c := s[r]; c <= ' ' || (c == '.' && r > slash) || c == '%' || c == '"' || c >= 0x7F {
+			n++
+		}
+	}
+
+	// quick exit
+	if n == 0 {
+		return s
+	}
+
+	// escape
+	const hex = "0123456789abcdef"
+	p := make([]byte, 0, len(s)+2*n)
+	for r := 0; r < len(s); r++ {
+		if c := s[r]; c <= ' ' || (c == '.' && r > slash) || c == '%' || c == '"' || c >= 0x7F {
+			p = append(p, '%', hex[c>>4], hex[c&0xF])
+		} else {
+			p = append(p, c)
+		}
+	}
+
+	return string(p)
+}
+
 func open(name string) (*Plugin, error) {
 	cPath := (*C.char)(C.malloc(C.PATH_MAX + 1))
 	defer C.free(unsafe.Pointer(cPath))
@@ -82,7 +123,6 @@
 	p := &Plugin{
 		pluginpath: pluginpath,
 		loaded:     make(chan struct{}),
-		syms:       syms,
 	}
 	plugins[filepath] = p
 	pluginsMu.Unlock()
@@ -97,14 +137,14 @@
 	}
 
 	// Fill out the value of each plugin symbol.
+	updatedSyms := map[string]interface{}{}
 	for symName, sym := range syms {
 		isFunc := symName[0] == '.'
 		if isFunc {
 			delete(syms, symName)
 			symName = symName[1:]
 		}
-
-		cname := C.CString(pluginpath + "." + symName)
+		cname := C.CString(pathToPrefix(pluginpath) + "." + symName)
 		p := C.pluginLookup(h, cname, &cErr)
 		C.free(unsafe.Pointer(cname))
 		if p == nil {
@@ -116,8 +156,12 @@
 		} else {
 			(*valp)[1] = p
 		}
-		syms[symName] = sym
+		// we can't add to syms during iteration as we'll end up processing
+		// some symbols twice with the inability to tell if the symbol is a function
+		updatedSyms[symName] = sym
 	}
+	p.syms = updatedSyms
+
 	close(p.loaded)
 	return p, nil
 }
diff --git a/libgo/go/reflect/all_test.go b/libgo/go/reflect/all_test.go
index 6ac3352..7364673 100644
--- a/libgo/go/reflect/all_test.go
+++ b/libgo/go/reflect/all_test.go
@@ -1576,9 +1576,11 @@
 			args := []Value{size.arg}
 			b.SetBytes(int64(size.arg.Len()))
 			b.ResetTimer()
-			for i := 0; i < b.N; i++ {
-				size.fv.Call(args)
-			}
+			b.RunParallel(func(pb *testing.PB) {
+				for pb.Next() {
+					size.fv.Call(args)
+				}
+			})
 		}
 		name := fmt.Sprintf("size=%v", size.arg.Len())
 		b.Run(name, bench)
@@ -2559,6 +2561,28 @@
 	}
 }
 
+func BenchmarkPtrTo(b *testing.B) {
+	// Construct a type with a zero ptrToThis.
+	type T struct{ int }
+	t := SliceOf(TypeOf(T{}))
+	ptrToThis := ValueOf(t).Elem().FieldByName("ptrToThis")
+	if !ptrToThis.IsValid() {
+		b.Fatalf("%v has no ptrToThis field; was it removed from rtype?", t)
+	}
+	if ptrToThis.Int() != 0 {
+		b.Fatalf("%v.ptrToThis unexpectedly nonzero", t)
+	}
+	b.ResetTimer()
+
+	// Now benchmark calling PtrTo on it: we'll have to hit the ptrMap cache on
+	// every call.
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			PtrTo(t)
+		}
+	})
+}
+
 func TestAddr(t *testing.T) {
 	var p struct {
 		X, Y int
@@ -3738,7 +3762,7 @@
 
 func TestArrayOf(t *testing.T) {
 	// check construction and use of type not in binary
-	for _, table := range []struct {
+	tests := []struct {
 		n          int
 		value      func(i int) interface{}
 		comparable bool
@@ -3816,7 +3840,9 @@
 			comparable: true,
 			want:       "[{0 0} {1 1} {2 2} {3 3} {4 4} {5 5} {6 6} {7 7} {8 8} {9 9}]",
 		},
-	} {
+	}
+
+	for _, table := range tests {
 		at := ArrayOf(table.n, TypeOf(table.value(0)))
 		v := New(at).Elem()
 		vok := New(at).Elem()
@@ -4045,6 +4071,54 @@
 	}
 }
 
+func TestStructOfFieldName(t *testing.T) {
+	// invalid field name "1nvalid"
+	shouldPanic(func() {
+		StructOf([]StructField{
+			StructField{Name: "valid", Type: TypeOf("")},
+			StructField{Name: "1nvalid", Type: TypeOf("")},
+		})
+	})
+
+	// invalid field name "+"
+	shouldPanic(func() {
+		StructOf([]StructField{
+			StructField{Name: "val1d", Type: TypeOf("")},
+			StructField{Name: "+", Type: TypeOf("")},
+		})
+	})
+
+	// no field name
+	shouldPanic(func() {
+		StructOf([]StructField{
+			StructField{Name: "", Type: TypeOf("")},
+		})
+	})
+
+	// verify creation of a struct with valid struct fields
+	validFields := []StructField{
+		StructField{
+			Name: "φ",
+			Type: TypeOf(""),
+		},
+		StructField{
+			Name: "ValidName",
+			Type: TypeOf(""),
+		},
+		StructField{
+			Name: "Val1dNam5",
+			Type: TypeOf(""),
+		},
+	}
+
+	validStruct := StructOf(validFields)
+
+	const structStr = `struct { φ string; ValidName string; Val1dNam5 string }`
+	if got, want := validStruct.String(), structStr; got != want {
+		t.Errorf("StructOf(validFields).String()=%q, want %q", got, want)
+	}
+}
+
 func TestStructOf(t *testing.T) {
 	// check construction and use of type not in binary
 	fields := []StructField{
@@ -4392,7 +4466,7 @@
 		{Name: "S1", Type: st1},
 	})
 
-	for _, table := range []struct {
+	tests := []struct {
 		rt  Type
 		idx []int
 	}{
@@ -4473,7 +4547,9 @@
 			),
 			idx: []int{2},
 		},
-	} {
+	}
+
+	for _, table := range tests {
 		v1 := New(table.rt).Elem()
 		v2 := New(table.rt).Elem()
 
@@ -4582,18 +4658,21 @@
 	type Iface interface {
 		Get() int
 	}
-	for i, table := range []struct {
+	tests := []struct {
+		name string
 		typ  Type
 		val  Value
 		impl bool
 	}{
 		{
+			name: "StructI",
 			typ:  TypeOf(StructI(want)),
 			val:  ValueOf(StructI(want)),
 			impl: true,
 		},
 		{
-			typ: PtrTo(TypeOf(StructI(want))),
+			name: "StructI",
+			typ:  PtrTo(TypeOf(StructI(want))),
 			val: ValueOf(func() interface{} {
 				v := StructI(want)
 				return &v
@@ -4601,7 +4680,8 @@
 			impl: true,
 		},
 		{
-			typ: PtrTo(TypeOf(StructIPtr(want))),
+			name: "StructIPtr",
+			typ:  PtrTo(TypeOf(StructIPtr(want))),
 			val: ValueOf(func() interface{} {
 				v := StructIPtr(want)
 				return &v
@@ -4609,6 +4689,7 @@
 			impl: true,
 		},
 		{
+			name: "StructIPtr",
 			typ:  TypeOf(StructIPtr(want)),
 			val:  ValueOf(StructIPtr(want)),
 			impl: false,
@@ -4618,41 +4699,70 @@
 		//	val:  ValueOf(StructI(want)),
 		//	impl: true,
 		// },
-	} {
-		rt := StructOf(
-			[]StructField{
-				{
-					Name:    "",
+	}
+
+	for i, table := range tests {
+		for j := 0; j < 2; j++ {
+			var fields []StructField
+			if j == 1 {
+				fields = append(fields, StructField{
+					Name:    "Dummy",
 					PkgPath: "",
-					Type:    table.typ,
-				},
-			},
-		)
-		rv := New(rt).Elem()
-		rv.Field(0).Set(table.val)
-
-		if _, ok := rv.Interface().(Iface); ok != table.impl {
-			if table.impl {
-				t.Errorf("test-%d: type=%v fails to implement Iface.\n", i, table.typ)
-			} else {
-				t.Errorf("test-%d: type=%v should NOT implement Iface\n", i, table.typ)
+					Type:    TypeOf(int(0)),
+				})
 			}
-			continue
-		}
+			fields = append(fields, StructField{
+				Name:      table.name,
+				Anonymous: true,
+				PkgPath:   "",
+				Type:      table.typ,
+			})
 
-		if !table.impl {
-			continue
-		}
+			// We currently do not correctly implement methods
+			// for anonymous fields other than the first.
+			// Therefore, for now, we expect those methods
+			// to not exist.  See issues 15924 and 20824.
+			// When those issues are fixed, this test of panic
+			// should be removed.
+			if j == 1 && table.impl {
+				func() {
+					defer func() {
+						if err := recover(); err == nil {
+							t.Errorf("test-%d-%d did not panic", i, j)
+						}
+					}()
+					_ = StructOf(fields)
+				}()
+				continue
+			}
 
-		v := rv.Interface().(Iface).Get()
-		if v != want {
-			t.Errorf("test-%d: x.Get()=%v. want=%v\n", i, v, want)
-		}
+			rt := StructOf(fields)
+			rv := New(rt).Elem()
+			rv.Field(j).Set(table.val)
 
-		fct := rv.MethodByName("Get")
-		out := fct.Call(nil)
-		if !DeepEqual(out[0].Interface(), want) {
-			t.Errorf("test-%d: x.Get()=%v. want=%v\n", i, out[0].Interface(), want)
+			if _, ok := rv.Interface().(Iface); ok != table.impl {
+				if table.impl {
+					t.Errorf("test-%d-%d: type=%v fails to implement Iface.\n", i, j, table.typ)
+				} else {
+					t.Errorf("test-%d-%d: type=%v should NOT implement Iface\n", i, j, table.typ)
+				}
+				continue
+			}
+
+			if !table.impl {
+				continue
+			}
+
+			v := rv.Interface().(Iface).Get()
+			if v != want {
+				t.Errorf("test-%d-%d: x.Get()=%v. want=%v\n", i, j, v, want)
+			}
+
+			fct := rv.MethodByName("Get")
+			out := fct.Call(nil)
+			if !DeepEqual(out[0].Interface(), want) {
+				t.Errorf("test-%d-%d: x.Get()=%v. want=%v\n", i, j, out[0].Interface(), want)
+			}
 		}
 	}
 }
@@ -4914,16 +5024,20 @@
 
 func BenchmarkFieldByName1(b *testing.B) {
 	t := TypeOf(B1{})
-	for i := 0; i < b.N; i++ {
-		t.FieldByName("Z")
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			t.FieldByName("Z")
+		}
+	})
 }
 
 func BenchmarkFieldByName2(b *testing.B) {
 	t := TypeOf(S3{})
-	for i := 0; i < b.N; i++ {
-		t.FieldByName("B")
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			t.FieldByName("B")
+		}
+	})
 }
 
 type R0 struct {
@@ -5006,9 +5120,11 @@
 
 func BenchmarkFieldByName3(b *testing.B) {
 	t := TypeOf(R0{})
-	for i := 0; i < b.N; i++ {
-		t.FieldByName("X")
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			t.FieldByName("X")
+		}
+	})
 }
 
 type S struct {
@@ -5018,9 +5134,11 @@
 
 func BenchmarkInterfaceBig(b *testing.B) {
 	v := ValueOf(S{})
-	for i := 0; i < b.N; i++ {
-		v.Interface()
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			v.Interface()
+		}
+	})
 	b.StopTimer()
 }
 
@@ -5036,9 +5154,11 @@
 
 func BenchmarkInterfaceSmall(b *testing.B) {
 	v := ValueOf(int64(0))
-	for i := 0; i < b.N; i++ {
-		v.Interface()
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			v.Interface()
+		}
+	})
 }
 
 func TestAllocsInterfaceSmall(t *testing.T) {
@@ -5835,7 +5955,7 @@
 	check("SliceOf", SliceOf(TypeOf(T{})))
 }
 
-type XM struct{}
+type XM struct{ _ bool }
 
 func (*XM) String() string { return "" }
 
@@ -5861,6 +5981,24 @@
 	if allocs > 0.5 {
 		t.Errorf("allocs per map assignment: want 0 got %f", allocs)
 	}
+
+	const size = 1000
+	tmp := 0
+	val := ValueOf(&tmp).Elem()
+	allocs = testing.AllocsPerRun(100, func() {
+		mv := MakeMapWithSize(TypeOf(map[int]int{}), size)
+		// Only adding half of the capacity to not trigger re-allocations due too many overloaded buckets.
+		for i := 0; i < size/2; i++ {
+			val.SetInt(int64(i))
+			mv.SetMapIndex(val, val)
+		}
+	})
+	if allocs > 10 {
+		t.Errorf("allocs per map assignment: want at most 10 got %f", allocs)
+	}
+	// Empirical testing shows that with capacity hint single run will trigger 3 allocations and without 91. I set
+	// the threshold to 10, to not make it overly brittle if something changes in the initial allocation of the
+	// map, but to still catch a regression where we keep re-allocating in the hashmap as new entries are added.
 }
 
 func TestChanAlloc(t *testing.T) {
@@ -5984,6 +6122,8 @@
 		{TypeOf(new(XM)).Method(0).Type, "func(*reflect_test.XM) string"},
 		{ChanOf(3, TypeOf(XM{})), "chan reflect_test.XM"},
 		{MapOf(TypeOf(int(0)), TypeOf(XM{})), "map[int]reflect_test.XM"},
+		{ArrayOf(3, TypeOf(XM{})), "[3]reflect_test.XM"},
+		{ArrayOf(3, TypeOf(struct{}{})), "[3]struct {}"},
 	}
 
 	for i, test := range stringTests {
@@ -6014,9 +6154,11 @@
 
 func BenchmarkNew(b *testing.B) {
 	v := TypeOf(XM{})
-	for i := 0; i < b.N; i++ {
-		New(v)
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			New(v)
+		}
+	})
 }
 
 func TestSwapper(t *testing.T) {
@@ -6091,6 +6233,7 @@
 			want: []pairPtr{{5, 6, &c}, {3, 4, &b}, {1, 2, &a}},
 		},
 	}
+
 	for i, tt := range tests {
 		inStr := fmt.Sprint(tt.in)
 		Swapper(tt.in)(tt.i, tt.j)
@@ -6116,3 +6259,36 @@
 		lv.Set(rv)
 	})
 }
+
+type Tint int
+
+type Tint2 = Tint
+
+type Talias1 struct {
+	byte
+	uint8
+	int
+	int32
+	rune
+}
+
+type Talias2 struct {
+	Tint
+	Tint2
+}
+
+func TestAliasNames(t *testing.T) {
+	t1 := Talias1{byte: 1, uint8: 2, int: 3, int32: 4, rune: 5}
+	out := fmt.Sprintf("%#v", t1)
+	want := "reflect_test.Talias1{byte:0x1, uint8:0x2, int:3, int32:4, rune:5}"
+	if out != want {
+		t.Errorf("Talias1 print:\nhave: %s\nwant: %s", out, want)
+	}
+
+	t2 := Talias2{Tint: 1, Tint2: 2}
+	out = fmt.Sprintf("%#v", t2)
+	want = "reflect_test.Talias2{Tint:1, Tint2:2}"
+	if out != want {
+		t.Errorf("Talias2 print:\nhave: %s\nwant: %s", out, want)
+	}
+}
diff --git a/libgo/go/reflect/deepequal.go b/libgo/go/reflect/deepequal.go
index f3fd704..2fdd6a3 100644
--- a/libgo/go/reflect/deepequal.go
+++ b/libgo/go/reflect/deepequal.go
@@ -178,6 +178,12 @@
 // DeepEqual has been defined so that the same short-cut applies
 // to slices and maps: if x and y are the same slice or the same map,
 // they are deeply equal regardless of content.
+//
+// As DeepEqual traverses the data values it may find a cycle. The
+// second and subsequent times that DeepEqual compares two pointer
+// values that have been compared before, it treats the values as
+// equal rather than examining the values to which they point.
+// This ensures that DeepEqual terminates.
 func DeepEqual(x, y interface{}) bool {
 	if x == nil || y == nil {
 		return x == y
diff --git a/libgo/go/reflect/set_test.go b/libgo/go/reflect/set_test.go
index bc35c78..7c39623 100644
--- a/libgo/go/reflect/set_test.go
+++ b/libgo/go/reflect/set_test.go
@@ -7,6 +7,7 @@
 import (
 	"bytes"
 	"go/ast"
+	"go/token"
 	"io"
 	. "reflect"
 	"testing"
@@ -172,6 +173,23 @@
 	{new(bytes.Buffer), new(io.Reader), false},
 	{new(*bytes.Buffer), new(io.ReaderAt), false},
 	{new(*ast.Ident), new(ast.Expr), true},
+	{new(*notAnExpr), new(ast.Expr), false},
+	{new(*ast.Ident), new(notASTExpr), false},
+	{new(notASTExpr), new(ast.Expr), false},
+	{new(ast.Expr), new(notASTExpr), false},
+	{new(*notAnExpr), new(notASTExpr), true},
+}
+
+type notAnExpr struct{}
+
+func (notAnExpr) Pos() token.Pos { return token.NoPos }
+func (notAnExpr) End() token.Pos { return token.NoPos }
+func (notAnExpr) exprNode()      {}
+
+type notASTExpr interface {
+	Pos() token.Pos
+	End() token.Pos
+	exprNode()
 }
 
 func TestImplements(t *testing.T) {
diff --git a/libgo/go/reflect/type.go b/libgo/go/reflect/type.go
index 97b986a..664d971 100644
--- a/libgo/go/reflect/type.go
+++ b/libgo/go/reflect/type.go
@@ -18,6 +18,8 @@
 import (
 	"strconv"
 	"sync"
+	"unicode"
+	"unicode/utf8"
 	"unsafe"
 )
 
@@ -258,6 +260,8 @@
 // It is embedded in other, public struct types, but always
 // with a unique tag like `reflect:"array"` or `reflect:"ptr"`
 // so that code cannot convert from, say, *arrayType to *ptrType.
+//
+// rtype must be kept in sync with ../runtime/type.go:/^type._type.
 type rtype struct {
 	size       uintptr
 	ptrdata    uintptr // size of memory prefix holding all pointers
@@ -516,79 +520,52 @@
 
 func (t *rtype) common() *rtype { return t }
 
-func (t *uncommonType) Method(i int) (m Method) {
-	if t == nil || i < 0 || i >= len(t.methods) {
-		panic("reflect: Method index out of range")
+var methodCache sync.Map // map[*rtype][]method
+
+func (t *rtype) exportedMethods() []method {
+	methodsi, found := methodCache.Load(t)
+	if found {
+		return methodsi.([]method)
 	}
-	found := false
-	for mi := range t.methods {
-		if t.methods[mi].pkgPath == nil {
-			if i == 0 {
-				i = mi
-				found = true
-				break
+
+	ut := t.uncommon()
+	if ut == nil {
+		return nil
+	}
+	allm := ut.methods
+	allExported := true
+	for _, m := range allm {
+		if m.pkgPath != nil {
+			allExported = false
+			break
+		}
+	}
+	var methods []method
+	if allExported {
+		methods = allm
+	} else {
+		methods = make([]method, 0, len(allm))
+		for _, m := range allm {
+			if m.pkgPath == nil {
+				methods = append(methods, m)
 			}
-			i--
 		}
-	}
-	if !found {
-		panic("reflect: Method index out of range")
+		methods = methods[:len(methods):len(methods)]
 	}
 
-	p := &t.methods[i]
-	if p.name != nil {
-		m.Name = *p.name
-	}
-	fl := flag(Func)
-	if p.pkgPath != nil {
-		m.PkgPath = *p.pkgPath
-		fl |= flagStickyRO
-	}
-	mt := p.typ
-	m.Type = toType(mt)
-	x := new(unsafe.Pointer)
-	*x = unsafe.Pointer(&p.tfn)
-	m.Func = Value{mt, unsafe.Pointer(x), fl | flagIndir | flagMethodFn}
-	m.Index = i
-	return
+	methodsi, _ = methodCache.LoadOrStore(t, methods)
+	return methodsi.([]method)
 }
 
-func (t *uncommonType) NumMethod() int {
-	if t == nil {
-		return 0
-	}
-	c := 0
-	for i := range t.methods {
-		if t.methods[i].pkgPath == nil {
-			c++
-		}
-	}
-	return c
-}
-
-func (t *uncommonType) MethodByName(name string) (m Method, ok bool) {
-	if t == nil {
-		return
-	}
-	var p *method
-	for i := range t.methods {
-		p = &t.methods[i]
-		if p.pkgPath == nil && p.name != nil && *p.name == name {
-			return t.Method(i), true
-		}
-	}
-	return
-}
-
-// TODO(rsc): gc supplies these, but they are not
-// as efficient as they could be: they have commonType
-// as the receiver instead of *rtype.
 func (t *rtype) NumMethod() int {
 	if t.Kind() == Interface {
 		tt := (*interfaceType)(unsafe.Pointer(t))
 		return tt.NumMethod()
 	}
-	return t.uncommonType.NumMethod()
+	if t.uncommonType == nil {
+		return 0 // avoid methodCache synchronization
+	}
+	return len(t.exportedMethods())
 }
 
 func (t *rtype) Method(i int) (m Method) {
@@ -596,7 +573,22 @@
 		tt := (*interfaceType)(unsafe.Pointer(t))
 		return tt.Method(i)
 	}
-	return t.uncommonType.Method(i)
+	methods := t.exportedMethods()
+	if i < 0 || i >= len(methods) {
+		panic("reflect: Method index out of range")
+	}
+	p := methods[i]
+	if p.name != nil {
+		m.Name = *p.name
+	}
+	fl := flag(Func)
+	mt := p.typ
+	m.Type = toType(mt)
+	x := new(unsafe.Pointer)
+	*x = unsafe.Pointer(&p.tfn)
+	m.Func = Value{mt, unsafe.Pointer(x), fl | flagIndir | flagMethodFn}
+	m.Index = i
+	return m
 }
 
 func (t *rtype) MethodByName(name string) (m Method, ok bool) {
@@ -604,7 +596,17 @@
 		tt := (*interfaceType)(unsafe.Pointer(t))
 		return tt.MethodByName(name)
 	}
-	return t.uncommonType.MethodByName(name)
+	ut := t.uncommon()
+	if ut == nil {
+		return Method{}, false
+	}
+	for i := range ut.methods {
+		p := &ut.methods[i]
+		if p.pkgPath == nil && p.name != nil && *p.name == name {
+			return t.Method(i), true
+		}
+	}
+	return Method{}, false
 }
 
 func (t *rtype) PkgPath() string {
@@ -983,12 +985,11 @@
 			visited[t] = true
 			for i := range t.fields {
 				f := &t.fields[i]
-				// Find name and type for field f.
+				// Find name and (for anonymous field) type for field f.
 				fname := *f.name
 				var ntyp *rtype
 				if f.anon() {
 					// Anonymous field of type T or *T.
-					// Name taken from type.
 					ntyp = f.typ
 					if ntyp.Kind() == Ptr {
 						ntyp = ntyp.Elem().common()
@@ -1072,10 +1073,7 @@
 }
 
 // ptrMap is the cache for PtrTo.
-var ptrMap struct {
-	sync.RWMutex
-	m map[*rtype]*ptrType
-}
+var ptrMap sync.Map // map[*rtype]*ptrType
 
 // PtrTo returns the pointer type with element t.
 // For example, if t represents type Foo, PtrTo(t) represents *Foo.
@@ -1089,24 +1087,8 @@
 	}
 
 	// Check the cache.
-	ptrMap.RLock()
-	if m := ptrMap.m; m != nil {
-		if p := m[t]; p != nil {
-			ptrMap.RUnlock()
-			return &p.rtype
-		}
-	}
-	ptrMap.RUnlock()
-
-	ptrMap.Lock()
-	if ptrMap.m == nil {
-		ptrMap.m = make(map[*rtype]*ptrType)
-	}
-	p := ptrMap.m[t]
-	if p != nil {
-		// some other goroutine won the race and created it
-		ptrMap.Unlock()
-		return &p.rtype
+	if pi, ok := ptrMap.Load(t); ok {
+		return &pi.(*ptrType).rtype
 	}
 
 	s := "*" + *t.string
@@ -1115,9 +1097,9 @@
 	r, ok := canonicalType[s]
 	canonicalTypeLock.RUnlock()
 	if ok {
-		ptrMap.m[t] = (*ptrType)(unsafe.Pointer(r.(*rtype)))
-		ptrMap.Unlock()
-		return r.(*rtype)
+		p := (*ptrType)(unsafe.Pointer(r.(*rtype)))
+		pi, _ := ptrMap.LoadOrStore(t, p)
+		return &pi.(*ptrType).rtype
 	}
 
 	// Create a new ptrType starting with the description
@@ -1143,11 +1125,10 @@
 	pp.elem = t
 
 	q := canonicalize(&pp.rtype)
-	p = (*ptrType)(unsafe.Pointer(q.(*rtype)))
+	p := (*ptrType)(unsafe.Pointer(q.(*rtype)))
 
-	ptrMap.m[t] = p
-	ptrMap.Unlock()
-	return &p.rtype
+	pi, _ := ptrMap.LoadOrStore(t, p)
+	return &pi.(*ptrType).rtype
 }
 
 // fnv1 incorporates the list of bytes into the hash x using the FNV-1 hash function.
@@ -1396,11 +1377,8 @@
 	return false
 }
 
-// The lookupCache caches ChanOf, MapOf, and SliceOf lookups.
-var lookupCache struct {
-	sync.RWMutex
-	m map[cacheKey]*rtype
-}
+// The lookupCache caches ArrayOf, ChanOf, MapOf and SliceOf lookups.
+var lookupCache sync.Map // map[cacheKey]*rtype
 
 // A cacheKey is the key for use in the lookupCache.
 // Four values describe any of the types we are looking for:
@@ -1412,48 +1390,15 @@
 	extra uintptr
 }
 
-// cacheGet looks for a type under the key k in the lookupCache.
-// If it finds one, it returns that type.
-// If not, it returns nil with the cache locked.
-// The caller is expected to use cachePut to unlock the cache.
-func cacheGet(k cacheKey) Type {
-	lookupCache.RLock()
-	t := lookupCache.m[k]
-	lookupCache.RUnlock()
-	if t != nil {
-		return t
-	}
-
-	lookupCache.Lock()
-	t = lookupCache.m[k]
-	if t != nil {
-		lookupCache.Unlock()
-		return t
-	}
-
-	if lookupCache.m == nil {
-		lookupCache.m = make(map[cacheKey]*rtype)
-	}
-
-	return nil
-}
-
-// cachePut stores the given type in the cache, unlocks the cache,
-// and returns the type. It is expected that the cache is locked
-// because cacheGet returned nil.
-func cachePut(k cacheKey, t *rtype) Type {
-	t = toType(t).common()
-	lookupCache.m[k] = t
-	lookupCache.Unlock()
-	return t
-}
-
 // The funcLookupCache caches FuncOf lookups.
 // FuncOf does not share the common lookupCache since cacheKey is not
 // sufficient to represent functions unambiguously.
 var funcLookupCache struct {
-	sync.RWMutex
-	m map[uint32][]*rtype // keyed by hash calculated in FuncOf
+	sync.Mutex // Guards stores (but not loads) on m.
+
+	// m is a map[uint32][]*rtype keyed by the hash calculated in FuncOf.
+	// Elements of m are append-only and thus safe for concurrent reading.
+	m sync.Map
 }
 
 // ChanOf returns the channel type with the given direction and element type.
@@ -1466,13 +1411,12 @@
 
 	// Look in cache.
 	ckey := cacheKey{Chan, typ, nil, uintptr(dir)}
-	if ch := cacheGet(ckey); ch != nil {
-		return ch
+	if ch, ok := lookupCache.Load(ckey); ok {
+		return ch.(*rtype)
 	}
 
 	// This restriction is imposed by the gc compiler and the runtime.
 	if typ.size >= 1<<16 {
-		lookupCache.Unlock()
 		panic("reflect.ChanOf: element size too large")
 	}
 
@@ -1481,7 +1425,6 @@
 	var s string
 	switch dir {
 	default:
-		lookupCache.Unlock()
 		panic("reflect.ChanOf: invalid dir")
 	case SendDir:
 		s = "chan<- " + *typ.string
@@ -1515,7 +1458,8 @@
 	ch.uncommonType = nil
 	ch.ptrToThis = nil
 
-	return cachePut(ckey, &ch.rtype)
+	ti, _ := lookupCache.LoadOrStore(ckey, &ch.rtype)
+	return ti.(Type)
 }
 
 func ismapkey(*rtype) bool // implemented in runtime
@@ -1536,8 +1480,8 @@
 
 	// Look in cache.
 	ckey := cacheKey{Map, ktyp, etyp, 0}
-	if mt := cacheGet(ckey); mt != nil {
-		return mt
+	if mt, ok := lookupCache.Load(ckey); ok {
+		return mt.(Type)
 	}
 
 	// Look in known types.
@@ -1576,7 +1520,8 @@
 	mt.reflexivekey = isReflexive(ktyp)
 	mt.needkeyupdate = needKeyUpdate(ktyp)
 
-	return cachePut(ckey, &mt.rtype)
+	ti, _ := lookupCache.LoadOrStore(ckey, &mt.rtype)
+	return ti.(Type)
 }
 
 // FuncOf returns the function type with the given argument and result types.
@@ -1625,37 +1570,41 @@
 	ft.dotdotdot = variadic
 
 	// Look in cache.
-	funcLookupCache.RLock()
-	for _, t := range funcLookupCache.m[hash] {
-		if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
-			funcLookupCache.RUnlock()
-			return t
+	if ts, ok := funcLookupCache.m.Load(hash); ok {
+		for _, t := range ts.([]*rtype) {
+			if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
+				return t
+			}
 		}
 	}
-	funcLookupCache.RUnlock()
 
 	// Not in cache, lock and retry.
 	funcLookupCache.Lock()
 	defer funcLookupCache.Unlock()
-	if funcLookupCache.m == nil {
-		funcLookupCache.m = make(map[uint32][]*rtype)
-	}
-	for _, t := range funcLookupCache.m[hash] {
-		if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
-			return t
+	if ts, ok := funcLookupCache.m.Load(hash); ok {
+		for _, t := range ts.([]*rtype) {
+			if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
+				return t
+			}
 		}
 	}
 
+	addToCache := func(tt *rtype) Type {
+		var rts []*rtype
+		if rti, ok := funcLookupCache.m.Load(hash); ok {
+			rts = rti.([]*rtype)
+		}
+		funcLookupCache.m.Store(hash, append(rts, tt))
+		return tt
+	}
+
 	str := funcStr(ft)
 
 	// Populate the remaining fields of ft and store in cache.
 	ft.string = &str
 	ft.uncommonType = nil
 	ft.ptrToThis = nil
-
-	funcLookupCache.m[hash] = append(funcLookupCache.m[hash], &ft.rtype)
-
-	return toType(&ft.rtype)
+	return addToCache(&ft.rtype)
 }
 
 // funcStr builds a string representation of a funcType.
@@ -1771,9 +1720,6 @@
 	// Prepare GC data if any.
 	// A bucket is at most bucketSize*(1+maxKeySize+maxValSize)+2*ptrSize bytes,
 	// or 2072 bytes, or 259 pointer-size words, or 33 bytes of pointer bitmap.
-	// Normally the enforced limit on pointer maps is 16 bytes,
-	// but larger ones are acceptable, 33 bytes isn't too too big,
-	// and it's easier to generate a pointer bitmap than a GC program.
 	// Note that since the key and value are known to be <= 128 bytes,
 	// they're guaranteed to have bitmaps instead of GC programs.
 	var gcdata *byte
@@ -1812,7 +1758,7 @@
 				panic("reflect: unexpected GC program in MapOf")
 			}
 			kmask := (*[16]byte)(unsafe.Pointer(ktyp.gcdata))
-			for i := uintptr(0); i < ktyp.size/ptrSize; i++ {
+			for i := uintptr(0); i < ktyp.ptrdata/ptrSize; i++ {
 				if (kmask[i/8]>>(i%8))&1 != 0 {
 					for j := uintptr(0); j < bucketSize; j++ {
 						word := base + j*ktyp.size/ptrSize + i
@@ -1830,7 +1776,7 @@
 				panic("reflect: unexpected GC program in MapOf")
 			}
 			emask := (*[16]byte)(unsafe.Pointer(etyp.gcdata))
-			for i := uintptr(0); i < etyp.size/ptrSize; i++ {
+			for i := uintptr(0); i < etyp.ptrdata/ptrSize; i++ {
 				if (emask[i/8]>>(i%8))&1 != 0 {
 					for j := uintptr(0); j < bucketSize; j++ {
 						word := base + j*etyp.size/ptrSize + i
@@ -1871,8 +1817,8 @@
 
 	// Look in cache.
 	ckey := cacheKey{Slice, typ, nil, 0}
-	if slice := cacheGet(ckey); slice != nil {
-		return slice
+	if slice, ok := lookupCache.Load(ckey); ok {
+		return slice.(Type)
 	}
 
 	// Look in known types.
@@ -1892,17 +1838,44 @@
 	slice.uncommonType = nil
 	slice.ptrToThis = nil
 
-	return cachePut(ckey, &slice.rtype)
+	ti, _ := lookupCache.LoadOrStore(ckey, &slice.rtype)
+	return ti.(Type)
 }
 
 // The structLookupCache caches StructOf lookups.
 // StructOf does not share the common lookupCache since we need to pin
 // the memory associated with *structTypeFixedN.
 var structLookupCache struct {
-	sync.RWMutex
-	m map[uint32][]interface {
-		common() *rtype
-	} // keyed by hash calculated in StructOf
+	sync.Mutex // Guards stores (but not loads) on m.
+
+	// m is a map[uint32][]Type keyed by the hash calculated in StructOf.
+	// Elements in m are append-only and thus safe for concurrent reading.
+	m sync.Map
+}
+
+// isLetter returns true if a given 'rune' is classified as a Letter.
+func isLetter(ch rune) bool {
+	return 'a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' || ch == '_' || ch >= utf8.RuneSelf && unicode.IsLetter(ch)
+}
+
+// isValidFieldName checks if a string is a valid (struct) field name or not.
+//
+// According to the language spec, a field name should be an identifier.
+//
+// identifier = letter { letter | unicode_digit } .
+// letter = unicode_letter | "_" .
+func isValidFieldName(fieldName string) bool {
+	for i, c := range fieldName {
+		if i == 0 && !isLetter(c) {
+			return false
+		}
+
+		if !(isLetter(c) || unicode.IsDigit(c)) {
+			return false
+		}
+	}
+
+	return len(fieldName) > 0
 }
 
 // StructOf returns the struct type containing fields.
@@ -1930,6 +1903,12 @@
 	lastzero := uintptr(0)
 	repr = append(repr, "struct {"...)
 	for i, field := range fields {
+		if field.Name == "" {
+			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has no name")
+		}
+		if !isValidFieldName(field.Name) {
+			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has invalid name")
+		}
 		if field.Type == nil {
 			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has no type")
 		}
@@ -1960,30 +1939,29 @@
 			} else {
 				name = ft.String()
 			}
-			// TODO(sbinet) check for syntactically impossible type names?
 
 			switch f.typ.Kind() {
 			case Interface:
 				ift := (*interfaceType)(unsafe.Pointer(ft))
 				if len(ift.methods) > 0 {
-					panic("reflect.StructOf: embedded field with methods not supported")
+					panic("reflect.StructOf: embedded field with methods not implemented")
 				}
 			case Ptr:
 				ptr := (*ptrType)(unsafe.Pointer(ft))
 				if unt := ptr.uncommon(); unt != nil {
 					if len(unt.methods) > 0 {
-						panic("reflect.StructOf: embedded field with methods not supported")
+						panic("reflect.StructOf: embedded field with methods not implemented")
 					}
 				}
 				if unt := ptr.elem.uncommon(); unt != nil {
 					if len(unt.methods) > 0 {
-						panic("reflect.StructOf: embedded field with methods not supported")
+						panic("reflect.StructOf: embedded field with methods not implemented")
 					}
 				}
 			default:
 				if unt := ft.uncommon(); unt != nil {
 					if len(unt.methods) > 0 {
-						panic("reflect.StructOf: embedded field with methods not supported")
+						panic("reflect.StructOf: embedded field with methods not implemented")
 					}
 				}
 			}
@@ -2044,32 +2022,37 @@
 	*typ = *prototype
 	typ.fields = fs
 
-	// Look in cache
-	structLookupCache.RLock()
-	for _, st := range structLookupCache.m[hash] {
-		t := st.common()
-		if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
-			structLookupCache.RUnlock()
-			return t
+	// Look in cache.
+	if ts, ok := structLookupCache.m.Load(hash); ok {
+		for _, st := range ts.([]Type) {
+			t := st.common()
+			if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
+				return t
+			}
 		}
 	}
-	structLookupCache.RUnlock()
 
-	// not in cache, lock and retry
+	// Not in cache, lock and retry.
 	structLookupCache.Lock()
 	defer structLookupCache.Unlock()
-	if structLookupCache.m == nil {
-		structLookupCache.m = make(map[uint32][]interface {
-			common() *rtype
-		})
-	}
-	for _, st := range structLookupCache.m[hash] {
-		t := st.common()
-		if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
-			return t
+	if ts, ok := structLookupCache.m.Load(hash); ok {
+		for _, st := range ts.([]Type) {
+			t := st.common()
+			if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
+				return t
+			}
 		}
 	}
 
+	addToCache := func(t Type) Type {
+		var ts []Type
+		if ti, ok := structLookupCache.m.Load(hash); ok {
+			ts = ti.([]Type)
+		}
+		structLookupCache.m.Store(hash, append(ts, t))
+		return t
+	}
+
 	typ.string = &str
 	typ.hash = hash
 	typ.size = size
@@ -2172,24 +2155,19 @@
 	typ.uncommonType = nil
 	typ.ptrToThis = nil
 
-	structLookupCache.m[hash] = append(structLookupCache.m[hash], typ)
-	return &typ.rtype
+	return addToCache(&typ.rtype)
 }
 
 func runtimeStructField(field StructField) structField {
-	var name *string
-	if field.Name == "" {
-		t := field.Type.(*rtype)
-		if t.Kind() == Ptr {
-			t = t.Elem().(*rtype)
-		}
-	} else if field.PkgPath == "" {
-		s := field.Name
-		name = &s
-		b0 := s[0]
-		if ('a' <= b0 && b0 <= 'z') || b0 == '_' {
-			panic("reflect.StructOf: field \"" + field.Name + "\" is unexported but has no PkgPath")
-		}
+	if field.PkgPath != "" {
+		panic("reflect.StructOf: StructOf does not allow unexported fields")
+	}
+
+	// Best-effort check for misuse.
+	// Since PkgPath is empty, not much harm done if Unicode lowercase slips through.
+	c := field.Name[0]
+	if 'a' <= c && c <= 'z' || c == '_' {
+		panic("reflect.StructOf: field \"" + field.Name + "\" is unexported but missing PkgPath")
 	}
 
 	offsetAnon := uintptr(0)
@@ -2197,24 +2175,18 @@
 		offsetAnon |= 1
 	}
 
-	var pkgPath *string
-	if field.PkgPath != "" {
-		s := field.PkgPath
-		pkgPath = &s
-		// This could work with gccgo but we panic to be
-		// compatible with gc.
-		panic("reflect: creating a name with a package path is not supported")
-	}
+	s := field.Name
+	name := &s
 
 	var tag *string
 	if field.Tag != "" {
-		s := string(field.Tag)
-		tag = &s
+		st := string(field.Tag)
+		tag = &st
 	}
 
 	return structField{
 		name:       name,
-		pkgPath:    pkgPath,
+		pkgPath:    nil,
 		typ:        field.Type.common(),
 		tag:        tag,
 		offsetAnon: offsetAnon,
@@ -2257,15 +2229,11 @@
 // ArrayOf panics.
 func ArrayOf(count int, elem Type) Type {
 	typ := elem.(*rtype)
-	// call SliceOf here as it calls cacheGet/cachePut.
-	// ArrayOf also calls cacheGet/cachePut and thus may modify the state of
-	// the lookupCache mutex.
-	slice := SliceOf(elem)
 
 	// Look in cache.
 	ckey := cacheKey{Array, typ, nil, uintptr(count)}
-	if array := cacheGet(ckey); array != nil {
-		return array
+	if array, ok := lookupCache.Load(ckey); ok {
+		return array.(Type)
 	}
 
 	// Look in known types.
@@ -2287,9 +2255,11 @@
 
 	array.elem = typ
 	array.ptrToThis = nil
-	max := ^uintptr(0) / typ.size
-	if uintptr(count) > max {
-		panic("reflect.ArrayOf: array size would exceed virtual address space")
+	if typ.size > 0 {
+		max := ^uintptr(0) / typ.size
+		if uintptr(count) > max {
+			panic("reflect.ArrayOf: array size would exceed virtual address space")
+		}
 	}
 	array.size = typ.size * uintptr(count)
 	if count > 0 && typ.ptrdata != 0 {
@@ -2299,7 +2269,7 @@
 	array.fieldAlign = typ.fieldAlign
 	array.uncommonType = nil
 	array.len = uintptr(count)
-	array.slice = slice.(*rtype)
+	array.slice = SliceOf(elem).(*rtype)
 
 	array.kind &^= kindNoPointers
 	switch {
@@ -2413,7 +2383,8 @@
 		}
 	}
 
-	return cachePut(ckey, &array.rtype)
+	ti, _ := lookupCache.LoadOrStore(ckey, &array.rtype)
+	return ti.(Type)
 }
 
 func appendVarint(x []byte, v uintptr) []byte {
@@ -2466,7 +2437,7 @@
 	return t.kind&kindDirectIface == 0
 }
 
-// Layout matches runtime.BitVector (well enough).
+// Layout matches runtime.gobitvector (well enough).
 type bitVector struct {
 	n    uint32 // number of bits
 	data []byte
diff --git a/libgo/go/reflect/value.go b/libgo/go/reflect/value.go
index 8f6a93b..792699a 100644
--- a/libgo/go/reflect/value.go
+++ b/libgo/go/reflect/value.go
@@ -30,9 +30,9 @@
 // the underlying Go value can be used concurrently for the equivalent
 // direct operations.
 //
-// Using == on two Values does not compare the underlying values
-// they represent, but rather the contents of the Value structs.
 // To compare two Values, compare the results of the Interface method.
+// Using == on two Values does not compare the underlying values
+// they represent.
 type Value struct {
 	// typ holds the type of the value represented by a Value.
 	typ *rtype
@@ -1000,7 +1000,7 @@
 	return Value{v.typ, v.ptr, fl}
 }
 
-// NumMethod returns the number of methods in the value's method set.
+// NumMethod returns the number of exported methods in the value's method set.
 func (v Value) NumMethod() int {
 	if v.typ == nil {
 		panic(&ValueError{"reflect.Value.NumMethod", Invalid})
@@ -1933,12 +1933,18 @@
 	return Value{typ.common(), unsafe.Pointer(&ch), flag(Chan) | flagIndir}
 }
 
-// MakeMap creates a new map of the specified type.
+// MakeMap creates a new map with the specified type.
 func MakeMap(typ Type) Value {
+	return MakeMapWithSize(typ, 0)
+}
+
+// MakeMapWithSize creates a new map with the specified type
+// and initial space for approximately n elements.
+func MakeMapWithSize(typ Type, n int) Value {
 	if typ.Kind() != Map {
-		panic("reflect.MakeMap of non-map type")
+		panic("reflect.MakeMapWithSize of non-map type")
 	}
-	m := makemap(typ.(*rtype))
+	m := makemap(typ.(*rtype), n)
 	return Value{typ.common(), unsafe.Pointer(&m), flag(Map) | flagIndir}
 }
 
@@ -2015,7 +2021,6 @@
 	case directlyAssignable(dst, v.typ):
 		// Overwrite type so that they match.
 		// Same memory layout, so no harm done.
-		v.typ = dst
 		fl := v.flag & (flagRO | flagAddr | flagIndir)
 		fl |= flag(dst.Kind())
 		return Value{dst, v.ptr, fl}
@@ -2333,7 +2338,7 @@
 func chansend(ch unsafe.Pointer, val unsafe.Pointer, nb bool) bool
 
 func makechan(typ *rtype, size uint64) (ch unsafe.Pointer)
-func makemap(t *rtype) (m unsafe.Pointer)
+func makemap(t *rtype, cap int) (m unsafe.Pointer)
 
 //go:noescape
 func mapaccess(t *rtype, m unsafe.Pointer, key unsafe.Pointer) (val unsafe.Pointer)
diff --git a/libgo/go/regexp/all_test.go b/libgo/go/regexp/all_test.go
index beb46e7..28fe20c 100644
--- a/libgo/go/regexp/all_test.go
+++ b/libgo/go/regexp/all_test.go
@@ -9,6 +9,7 @@
 	"regexp/syntax"
 	"strings"
 	"testing"
+	"unicode/utf8"
 )
 
 var goodRe = []string{
@@ -354,6 +355,7 @@
 var metaTests = []MetaTest{
 	{``, ``, ``, true},
 	{`foo`, `foo`, `foo`, true},
+	{`日本語+`, `日本語\+`, `日本語`, false},
 	{`foo\.\$`, `foo\\\.\\\$`, `foo.$`, true}, // has meta but no operator
 	{`foo.\$`, `foo\.\\\$`, `foo`, false},     // has escaped operators and real operators
 	{`!@#$%^&*()_+-=[{]}\|,<.>/?~`, `!@#\$%\^&\*\(\)_\+-=\[\{\]\}\\\|,<\.>/\?~`, `!@#`, false},
@@ -822,7 +824,13 @@
 var sink string
 
 func BenchmarkQuoteMetaAll(b *testing.B) {
-	s := string(specialBytes)
+	specials := make([]byte, 0)
+	for i := byte(0); i < utf8.RuneSelf; i++ {
+		if special(i) {
+			specials = append(specials, i)
+		}
+	}
+	s := string(specials)
 	b.SetBytes(int64(len(s)))
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
diff --git a/libgo/go/regexp/exec.go b/libgo/go/regexp/exec.go
index 977619c..f8fe7b5 100644
--- a/libgo/go/regexp/exec.go
+++ b/libgo/go/regexp/exec.go
@@ -309,12 +309,14 @@
 // onepass runs the machine over the input starting at pos.
 // It reports whether a match was found.
 // If so, m.matchcap holds the submatch information.
-func (m *machine) onepass(i input, pos int) bool {
+// ncap is the number of captures.
+func (m *machine) onepass(i input, pos, ncap int) bool {
 	startCond := m.re.cond
 	if startCond == ^syntax.EmptyOp(0) { // impossible
 		return false
 	}
 	m.matched = false
+	m.matchcap = m.matchcap[:ncap]
 	for i := range m.matchcap {
 		m.matchcap[i] = -1
 	}
@@ -428,7 +430,7 @@
 		size = len(s)
 	}
 	if m.op != notOnePass {
-		if !m.onepass(i, pos) {
+		if !m.onepass(i, pos, ncap) {
 			re.put(m)
 			return nil
 		}
diff --git a/libgo/go/regexp/exec_test.go b/libgo/go/regexp/exec_test.go
index 766394d..5f8e747 100644
--- a/libgo/go/regexp/exec_test.go
+++ b/libgo/go/regexp/exec_test.go
@@ -681,6 +681,35 @@
 	}
 }
 
+func BenchmarkMatch_onepass_regex(b *testing.B) {
+	isRaceBuilder := strings.HasSuffix(testenv.Builder(), "-race")
+	r := MustCompile(`(?s)\A.*\z`)
+	if r.get().op == notOnePass {
+		b.Fatalf("want onepass regex, but %q is not onepass", r)
+	}
+	for _, size := range benchSizes {
+		if isRaceBuilder && size.n > 1<<10 {
+			continue
+		}
+		t := makeText(size.n)
+		bs := make([][]byte, len(t))
+		for i, s := range t {
+			bs[i] = []byte{s}
+		}
+		b.Run(size.name, func(b *testing.B) {
+			b.SetBytes(int64(size.n))
+			b.ReportAllocs()
+			for i := 0; i < b.N; i++ {
+				for _, byts := range bs {
+					if !r.Match(byts) {
+						b.Fatal("not match!")
+					}
+				}
+			}
+		})
+	}
+}
+
 var benchData = []struct{ name, re string }{
 	{"Easy0", "ABCDEFGHIJKLMNOPQRSTUVWXYZ$"},
 	{"Easy0i", "(?i)ABCDEFGHIJklmnopqrstuvwxyz$"},
diff --git a/libgo/go/regexp/onepass.go b/libgo/go/regexp/onepass.go
index 1b0564c..3ceb461 100644
--- a/libgo/go/regexp/onepass.go
+++ b/libgo/go/regexp/onepass.go
@@ -222,9 +222,10 @@
 	p := &onePassProg{
 		Start:  prog.Start,
 		NumCap: prog.NumCap,
+		Inst:   make([]onePassInst, len(prog.Inst)),
 	}
-	for _, inst := range prog.Inst {
-		p.Inst = append(p.Inst, onePassInst{Inst: inst})
+	for i, inst := range prog.Inst {
+		p.Inst[i] = onePassInst{Inst: inst}
 	}
 
 	// rewrites one or more common Prog constructs that enable some otherwise
@@ -304,13 +305,13 @@
 	var (
 		instQueue    = newQueue(len(p.Inst))
 		visitQueue   = newQueue(len(p.Inst))
-		check        func(uint32, map[uint32]bool) bool
+		check        func(uint32, []bool) bool
 		onePassRunes = make([][]rune, len(p.Inst))
 	)
 
 	// check that paths from Alt instructions are unambiguous, and rebuild the new
 	// program as a onepass program
-	check = func(pc uint32, m map[uint32]bool) (ok bool) {
+	check = func(pc uint32, m []bool) (ok bool) {
 		ok = true
 		inst := &p.Inst[pc]
 		if visitQueue.contains(pc) {
@@ -349,21 +350,20 @@
 			m[pc] = m[inst.Out]
 			// pass matching runes back through these no-ops.
 			onePassRunes[pc] = append([]rune{}, onePassRunes[inst.Out]...)
-			inst.Next = []uint32{}
-			for i := len(onePassRunes[pc]) / 2; i >= 0; i-- {
-				inst.Next = append(inst.Next, inst.Out)
+			inst.Next = make([]uint32, len(onePassRunes[pc])/2+1)
+			for i := range inst.Next {
+				inst.Next[i] = inst.Out
 			}
 		case syntax.InstEmptyWidth:
 			ok = check(inst.Out, m)
 			m[pc] = m[inst.Out]
 			onePassRunes[pc] = append([]rune{}, onePassRunes[inst.Out]...)
-			inst.Next = []uint32{}
-			for i := len(onePassRunes[pc]) / 2; i >= 0; i-- {
-				inst.Next = append(inst.Next, inst.Out)
+			inst.Next = make([]uint32, len(onePassRunes[pc])/2+1)
+			for i := range inst.Next {
+				inst.Next[i] = inst.Out
 			}
 		case syntax.InstMatch, syntax.InstFail:
 			m[pc] = inst.Op == syntax.InstMatch
-			break
 		case syntax.InstRune:
 			m[pc] = false
 			if len(inst.Next) > 0 {
@@ -387,9 +387,9 @@
 				runes = append(runes, inst.Rune...)
 			}
 			onePassRunes[pc] = runes
-			inst.Next = []uint32{}
-			for i := len(onePassRunes[pc]) / 2; i >= 0; i-- {
-				inst.Next = append(inst.Next, inst.Out)
+			inst.Next = make([]uint32, len(onePassRunes[pc])/2+1)
+			for i := range inst.Next {
+				inst.Next[i] = inst.Out
 			}
 			inst.Op = syntax.InstRune
 		case syntax.InstRune1:
@@ -411,9 +411,9 @@
 				runes = append(runes, inst.Rune[0], inst.Rune[0])
 			}
 			onePassRunes[pc] = runes
-			inst.Next = []uint32{}
-			for i := len(onePassRunes[pc]) / 2; i >= 0; i-- {
-				inst.Next = append(inst.Next, inst.Out)
+			inst.Next = make([]uint32, len(onePassRunes[pc])/2+1)
+			for i := range inst.Next {
+				inst.Next[i] = inst.Out
 			}
 			inst.Op = syntax.InstRune
 		case syntax.InstRuneAny:
@@ -431,9 +431,9 @@
 			}
 			instQueue.insert(inst.Out)
 			onePassRunes[pc] = append([]rune{}, anyRuneNotNL...)
-			inst.Next = []uint32{}
-			for i := len(onePassRunes[pc]) / 2; i >= 0; i-- {
-				inst.Next = append(inst.Next, inst.Out)
+			inst.Next = make([]uint32, len(onePassRunes[pc])/2+1)
+			for i := range inst.Next {
+				inst.Next[i] = inst.Out
 			}
 		}
 		return
@@ -441,7 +441,7 @@
 
 	instQueue.clear()
 	instQueue.insert(uint32(p.Start))
-	m := make(map[uint32]bool, len(p.Inst))
+	m := make([]bool, len(p.Inst))
 	for !instQueue.empty() {
 		visitQueue.clear()
 		pc := instQueue.next()
diff --git a/libgo/go/regexp/onepass_test.go b/libgo/go/regexp/onepass_test.go
index f4e336c..b1caa44 100644
--- a/libgo/go/regexp/onepass_test.go
+++ b/libgo/go/regexp/onepass_test.go
@@ -7,6 +7,7 @@
 import (
 	"reflect"
 	"regexp/syntax"
+	"strings"
 	"testing"
 )
 
@@ -173,6 +174,7 @@
 	{`^.bc(d|e)*$`, onePass},
 	{`^(?:(?:aa)|.)$`, notOnePass},
 	{`^(?:(?:a{1,2}){1,2})$`, notOnePass},
+	{`^l` + strings.Repeat("o", 2<<8) + `ng$`, onePass},
 }
 
 func TestCompileOnePass(t *testing.T) {
@@ -223,3 +225,23 @@
 		}
 	}
 }
+
+func BenchmarkCompileOnepass(b *testing.B) {
+	for _, test := range onePassTests {
+		if test.onePass == notOnePass {
+			continue
+		}
+		name := test.re
+		if len(name) > 20 {
+			name = name[:20] + "..."
+		}
+		b.Run(name, func(b *testing.B) {
+			b.ReportAllocs()
+			for i := 0; i < b.N; i++ {
+				if _, err := Compile(test.re); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	}
+}
diff --git a/libgo/go/regexp/regexp.go b/libgo/go/regexp/regexp.go
index 01093d4..b1af23e 100644
--- a/libgo/go/regexp/regexp.go
+++ b/libgo/go/regexp/regexp.go
@@ -76,7 +76,8 @@
 )
 
 // Regexp is the representation of a compiled regular expression.
-// A Regexp is safe for concurrent use by multiple goroutines.
+// A Regexp is safe for concurrent use by multiple goroutines,
+// except for configuration methods, such as Longest.
 type Regexp struct {
 	// read-only after Compile
 	regexpRO
@@ -159,6 +160,8 @@
 // That is, when matching against text, the regexp returns a match that
 // begins as early as possible in the input (leftmost), and among those
 // it chooses a match that is as long as possible.
+// This method modifies the Regexp and may not be called concurrently
+// with any other methods.
 func (re *Regexp) Longest() {
 	re.longest = true
 }
@@ -313,11 +316,19 @@
 
 func (i *inputString) context(pos int) syntax.EmptyOp {
 	r1, r2 := endOfText, endOfText
-	if pos > 0 && pos <= len(i.str) {
-		r1, _ = utf8.DecodeLastRuneInString(i.str[:pos])
+	// 0 < pos && pos <= len(i.str)
+	if uint(pos-1) < uint(len(i.str)) {
+		r1 = rune(i.str[pos-1])
+		if r1 >= utf8.RuneSelf {
+			r1, _ = utf8.DecodeLastRuneInString(i.str[:pos])
+		}
 	}
-	if pos < len(i.str) {
-		r2, _ = utf8.DecodeRuneInString(i.str[pos:])
+	// 0 <= pos && pos < len(i.str)
+	if uint(pos) < uint(len(i.str)) {
+		r2 = rune(i.str[pos])
+		if r2 >= utf8.RuneSelf {
+			r2, _ = utf8.DecodeRuneInString(i.str[pos:])
+		}
 	}
 	return syntax.EmptyOpContext(r1, r2)
 }
@@ -352,11 +363,19 @@
 
 func (i *inputBytes) context(pos int) syntax.EmptyOp {
 	r1, r2 := endOfText, endOfText
-	if pos > 0 && pos <= len(i.str) {
-		r1, _ = utf8.DecodeLastRune(i.str[:pos])
+	// 0 < pos && pos <= len(i.str)
+	if uint(pos-1) < uint(len(i.str)) {
+		r1 = rune(i.str[pos-1])
+		if r1 >= utf8.RuneSelf {
+			r1, _ = utf8.DecodeLastRune(i.str[:pos])
+		}
 	}
-	if pos < len(i.str) {
-		r2, _ = utf8.DecodeRune(i.str[pos:])
+	// 0 <= pos && pos < len(i.str)
+	if uint(pos) < uint(len(i.str)) {
+		r2 = rune(i.str[pos])
+		if r2 >= utf8.RuneSelf {
+			r2, _ = utf8.DecodeRune(i.str[pos:])
+		}
 	}
 	return syntax.EmptyOpContext(r1, r2)
 }
@@ -590,10 +609,18 @@
 	})
 }
 
-var specialBytes = []byte(`\.+*?()|[]{}^$`)
+// Bitmap used by func special to check whether a character needs to be escaped.
+var specialBytes [16]byte
 
+// special reports whether byte b needs to be escaped by QuoteMeta.
 func special(b byte) bool {
-	return bytes.IndexByte(specialBytes, b) >= 0
+	return b < utf8.RuneSelf && specialBytes[b%16]&(1<<(b/16)) != 0
+}
+
+func init() {
+	for _, b := range []byte(`\.+*?()|[]{}^$`) {
+		specialBytes[b%16] |= 1 << (b / 16)
+	}
 }
 
 // QuoteMeta returns a string that quotes all regular expression metacharacters
diff --git a/libgo/go/regexp/syntax/parse.go b/libgo/go/regexp/syntax/parse.go
index 7b8be55..8c6d43a 100644
--- a/libgo/go/regexp/syntax/parse.go
+++ b/libgo/go/regexp/syntax/parse.go
@@ -381,7 +381,7 @@
 		}
 	}
 	if op == OpAlternate {
-		re.Sub = p.factor(re.Sub, re.Flags)
+		re.Sub = p.factor(re.Sub)
 		if len(re.Sub) == 1 {
 			old := re
 			re = re.Sub[0]
@@ -402,7 +402,7 @@
 // which simplifies by character class introduction to
 //     A(B[CD]|EF)|BC[XY]
 //
-func (p *parser) factor(sub []*Regexp, flags Flags) []*Regexp {
+func (p *parser) factor(sub []*Regexp) []*Regexp {
 	if len(sub) < 2 {
 		return sub
 	}
diff --git a/libgo/go/runtime/cgo_gccgo.go b/libgo/go/runtime/cgo_gccgo.go
index 8236eea..c3bf955 100644
--- a/libgo/go/runtime/cgo_gccgo.go
+++ b/libgo/go/runtime/cgo_gccgo.go
@@ -6,7 +6,7 @@
 
 import (
 	"runtime/internal/atomic"
-	_ "unsafe"
+	"unsafe"
 )
 
 // For historical reasons these functions are called as though they
@@ -41,6 +41,7 @@
 	mp := getg().m
 	mp.ncgocall++
 	mp.ncgo++
+	mp.incgo = true
 	entersyscall(0)
 }
 
@@ -50,6 +51,7 @@
 	if gp == nil {
 		throw("no g in CgocallDone")
 	}
+	gp.m.incgo = false
 	gp.m.ncgo--
 
 	// If we are invoked because the C function called _cgo_panic,
@@ -68,15 +70,18 @@
 //     gofunction()
 //go:nosplit
 func CgocallBack() {
-	if getg() == nil || getg().m == nil {
+	gp := getg()
+	if gp == nil || gp.m == nil {
 		needm(0)
-		mp := getg().m
+		gp = getg()
+		mp := gp.m
 		mp.dropextram = true
 	}
 
 	exitsyscall(0)
+	gp.m.incgo = false
 
-	if getg().m.ncgo == 0 {
+	if gp.m.ncgo == 0 {
 		// The C call to Go came from a thread created by C.
 		// The C call to Go came from a thread not currently running
 		// any Go. In the case of -buildmode=c-archive or c-shared,
@@ -85,7 +90,7 @@
 		<-main_init_done
 	}
 
-	mp := getg().m
+	mp := gp.m
 	if mp.needextram || atomic.Load(&extraMWaiters) > 0 {
 		mp.needextram = false
 		newextram()
@@ -120,6 +125,7 @@
 		drop = true
 	}
 
+	gp.m.incgo = true
 	entersyscall(0)
 
 	if drop {
@@ -133,3 +139,8 @@
 	exitsyscall(0)
 	panic(gostringnocopy(p))
 }
+
+// cgo_yield exists in the gc toolchain to let TSAN deliver a signal.
+// gccgo does not need this.
+var cgo_yield = &_cgo_yield
+var _cgo_yield unsafe.Pointer
diff --git a/libgo/go/runtime/cgocheck.go b/libgo/go/runtime/cgocheck.go
index 09d444d..30f054b 100644
--- a/libgo/go/runtime/cgocheck.go
+++ b/libgo/go/runtime/cgocheck.go
@@ -125,7 +125,7 @@
 	aoff := uintptr(src) - mheap_.arena_start
 	idx := aoff >> _PageShift
 	s := mheap_.spans[idx]
-	if s.state == _MSpanStack {
+	if s.state == _MSpanManual {
 		// There are no heap bits for value stored on the stack.
 		// For a channel receive src might be on the stack of some
 		// other goroutine, so we can't unwind the stack even if
diff --git a/libgo/go/runtime/chan.go b/libgo/go/runtime/chan.go
index d2470bd..7bb919c 100644
--- a/libgo/go/runtime/chan.go
+++ b/libgo/go/runtime/chan.go
@@ -185,7 +185,7 @@
 	if sg := c.recvq.dequeue(); sg != nil {
 		// Found a waiting receiver. We pass the value we want to send
 		// directly to the receiver, bypassing the channel buffer (if any).
-		send(c, sg, ep, func() { unlock(&c.lock) })
+		send(c, sg, ep, func() { unlock(&c.lock) }, 3)
 		return true
 	}
 
@@ -256,7 +256,7 @@
 // Channel c must be empty and locked.  send unlocks c with unlockf.
 // sg must already be dequeued from c.
 // ep must be non-nil and point to the heap or the caller's stack.
-func send(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func()) {
+func send(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func(), skip int) {
 	if raceenabled {
 		if c.dataqsiz == 0 {
 			racesync(c, sg)
@@ -286,7 +286,7 @@
 	if sg.releasetime != 0 {
 		sg.releasetime = cputicks()
 	}
-	goready(gp, 4)
+	goready(gp, skip+1)
 }
 
 // Sends and receives on unbuffered or empty-buffered channels are the
@@ -466,7 +466,7 @@
 		// directly from sender. Otherwise, receive from head of queue
 		// and add sender's value to the tail of the queue (both map to
 		// the same buffer slot because the queue is full).
-		recv(c, sg, ep, func() { unlock(&c.lock) })
+		recv(c, sg, ep, func() { unlock(&c.lock) }, 3)
 		return true, true
 	}
 
@@ -542,7 +542,7 @@
 // Channel c must be full and locked. recv unlocks c with unlockf.
 // sg must already be dequeued from c.
 // A non-nil ep must point to the heap or the caller's stack.
-func recv(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func()) {
+func recv(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func(), skip int) {
 	if c.dataqsiz == 0 {
 		if raceenabled {
 			racesync(c, sg)
@@ -582,7 +582,7 @@
 	if sg.releasetime != 0 {
 		sg.releasetime = cputicks()
 	}
-	goready(gp, 4)
+	goready(gp, skip+1)
 }
 
 // compiler implements
diff --git a/libgo/go/runtime/cpuprof.go b/libgo/go/runtime/cpuprof.go
index e1206f9..b031b1a 100644
--- a/libgo/go/runtime/cpuprof.go
+++ b/libgo/go/runtime/cpuprof.go
@@ -3,118 +3,45 @@
 // license that can be found in the LICENSE file.
 
 // CPU profiling.
-// Based on algorithms and data structures used in
-// https://github.com/google/pprof.
-//
-// The main difference between this code and the google-perftools
-// code is that this code is written to allow copying the profile data
-// to an arbitrary io.Writer, while the google-perftools code always
-// writes to an operating system file.
 //
 // The signal handler for the profiling clock tick adds a new stack trace
-// to a hash table tracking counts for recent traces. Most clock ticks
-// hit in the cache. In the event of a cache miss, an entry must be
-// evicted from the hash table, copied to a log that will eventually be
-// written as profile data. The google-perftools code flushed the
-// log itself during the signal handler. This code cannot do that, because
-// the io.Writer might block or need system calls or locks that are not
-// safe to use from within the signal handler. Instead, we split the log
-// into two halves and let the signal handler fill one half while a goroutine
-// is writing out the other half. When the signal handler fills its half, it
-// offers to swap with the goroutine. If the writer is not done with its half,
-// we lose the stack trace for this clock tick (and record that loss).
-// The goroutine interacts with the signal handler by calling getprofile() to
-// get the next log piece to write, implicitly handing back the last log
-// piece it obtained.
-//
-// The state of this dance between the signal handler and the goroutine
-// is encoded in the Profile.handoff field. If handoff == 0, then the goroutine
-// is not using either log half and is waiting (or will soon be waiting) for
-// a new piece by calling notesleep(&p.wait).  If the signal handler
-// changes handoff from 0 to non-zero, it must call notewakeup(&p.wait)
-// to wake the goroutine. The value indicates the number of entries in the
-// log half being handed off. The goroutine leaves the non-zero value in
-// place until it has finished processing the log half and then flips the number
-// back to zero. Setting the high bit in handoff means that the profiling is over,
-// and the goroutine is now in charge of flushing the data left in the hash table
-// to the log and returning that data.
-//
-// The handoff field is manipulated using atomic operations.
-// For the most part, the manipulation of handoff is orderly: if handoff == 0
-// then the signal handler owns it and can change it to non-zero.
-// If handoff != 0 then the goroutine owns it and can change it to zero.
-// If that were the end of the story then we would not need to manipulate
-// handoff using atomic operations. The operations are needed, however,
-// in order to let the log closer set the high bit to indicate "EOF" safely
-// in the situation when normally the goroutine "owns" handoff.
+// to a log of recent traces. The log is read by a user goroutine that
+// turns it into formatted profile data. If the reader does not keep up
+// with the log, those writes will be recorded as a count of lost records.
+// The actual profile buffer is in profbuf.go.
 
 package runtime
 
 import (
 	"runtime/internal/atomic"
+	"runtime/internal/sys"
 	"unsafe"
 )
 
-const (
-	numBuckets      = 1 << 10
-	logSize         = 1 << 17
-	assoc           = 4
-	maxCPUProfStack = 64
-)
+const maxCPUProfStack = 64
 
-type cpuprofEntry struct {
-	count uintptr
-	depth int
-	stack [maxCPUProfStack]uintptr
-}
-
-//go:notinheap
 type cpuProfile struct {
-	on     bool    // profiling is on
-	wait   note    // goroutine waits here
-	count  uintptr // tick count
-	evicts uintptr // eviction count
-	lost   uintptr // lost ticks that need to be logged
+	lock mutex
+	on   bool     // profiling is on
+	log  *profBuf // profile events written here
 
-	// Active recent stack traces.
-	hash [numBuckets]struct {
-		entry [assoc]cpuprofEntry
-	}
-
-	// Log of traces evicted from hash.
-	// Signal handler has filled log[toggle][:nlog].
-	// Goroutine is writing log[1-toggle][:handoff].
-	log     [2][logSize / 2]uintptr
-	nlog    int
-	toggle  int32
-	handoff uint32
-
-	// Writer state.
-	// Writer maintains its own toggle to avoid races
-	// looking at signal handler's toggle.
-	wtoggle  uint32
-	wholding bool // holding & need to release a log half
-	flushing bool // flushing hash table - profile is over
-	eodSent  bool // special end-of-data record sent; => flushing
+	// extra holds extra stacks accumulated in addNonGo
+	// corresponding to profiling signals arriving on
+	// non-Go-created threads. Those stacks are written
+	// to log the next time a normal Go thread gets the
+	// signal handler.
+	// Assuming the stacks are 2 words each (we don't get
+	// a full traceback from those threads), plus one word
+	// size for framing, 100 Hz profiling would generate
+	// 300 words per second.
+	// Hopefully a normal Go thread will get the profiling
+	// signal at least once every few seconds.
+	extra     [1000]uintptr
+	numExtra  int
+	lostExtra uint64 // count of frames lost because extra is full
 }
 
-var (
-	cpuprofLock mutex
-	cpuprof     *cpuProfile
-
-	eod = [3]uintptr{0, 1, 0}
-)
-
-func setcpuprofilerate(hz int32) {
-	systemstack(func() {
-		setcpuprofilerate_m(hz)
-	})
-}
-
-// lostProfileData is a no-op function used in profiles
-// to mark the number of profiling stack traces that were
-// discarded due to slow data writers.
-func lostProfileData() {}
+var cpuprof cpuProfile
 
 // SetCPUProfileRate sets the CPU profiling rate to hz samples per second.
 // If hz <= 0, SetCPUProfileRate turns off profiling.
@@ -132,323 +59,153 @@
 		hz = 1000000
 	}
 
-	lock(&cpuprofLock)
+	lock(&cpuprof.lock)
 	if hz > 0 {
-		if cpuprof == nil {
-			cpuprof = (*cpuProfile)(sysAlloc(unsafe.Sizeof(cpuProfile{}), &memstats.other_sys))
-			if cpuprof == nil {
-				print("runtime: cpu profiling cannot allocate memory\n")
-				unlock(&cpuprofLock)
-				return
-			}
-		}
-		if cpuprof.on || cpuprof.handoff != 0 {
+		if cpuprof.on || cpuprof.log != nil {
 			print("runtime: cannot set cpu profile rate until previous profile has finished.\n")
-			unlock(&cpuprofLock)
+			unlock(&cpuprof.lock)
 			return
 		}
 
 		cpuprof.on = true
-		// pprof binary header format.
-		// https://github.com/gperftools/gperftools/blob/master/src/profiledata.cc#L119
-		p := &cpuprof.log[0]
-		p[0] = 0                 // count for header
-		p[1] = 3                 // depth for header
-		p[2] = 0                 // version number
-		p[3] = uintptr(1e6 / hz) // period (microseconds)
-		p[4] = 0
-		cpuprof.nlog = 5
-		cpuprof.toggle = 0
-		cpuprof.wholding = false
-		cpuprof.wtoggle = 0
-		cpuprof.flushing = false
-		cpuprof.eodSent = false
-		noteclear(&cpuprof.wait)
-
+		cpuprof.log = newProfBuf(1, 1<<17, 1<<14)
+		hdr := [1]uint64{uint64(hz)}
+		cpuprof.log.write(nil, nanotime(), hdr[:], nil)
 		setcpuprofilerate(int32(hz))
-	} else if cpuprof != nil && cpuprof.on {
+	} else if cpuprof.on {
 		setcpuprofilerate(0)
 		cpuprof.on = false
-
-		// Now add is not running anymore, and getprofile owns the entire log.
-		// Set the high bit in cpuprof.handoff to tell getprofile.
-		for {
-			n := cpuprof.handoff
-			if n&0x80000000 != 0 {
-				print("runtime: setcpuprofile(off) twice\n")
-			}
-			if atomic.Cas(&cpuprof.handoff, n, n|0x80000000) {
-				if n == 0 {
-					// we did the transition from 0 -> nonzero so we wake getprofile
-					notewakeup(&cpuprof.wait)
-				}
-				break
-			}
-		}
+		cpuprof.addExtra()
+		cpuprof.log.close()
 	}
-	unlock(&cpuprofLock)
+	unlock(&cpuprof.lock)
 }
 
 // add adds the stack trace to the profile.
 // It is called from signal handlers and other limited environments
 // and cannot allocate memory or acquire locks that might be
 // held at the time of the signal, nor can it use substantial amounts
-// of stack. It is allowed to call evict.
+// of stack.
 //go:nowritebarrierrec
-func (p *cpuProfile) add(pc []uintptr) {
-	p.addWithFlushlog(pc, p.flushlog)
+func (p *cpuProfile) add(gp *g, stk []uintptr) {
+	// Simple cas-lock to coordinate with setcpuprofilerate.
+	for !atomic.Cas(&prof.signalLock, 0, 1) {
+		osyield()
+	}
+
+	if prof.hz != 0 { // implies cpuprof.log != nil
+		if p.numExtra > 0 || p.lostExtra > 0 {
+			p.addExtra()
+		}
+		hdr := [1]uint64{1}
+		// Note: write "knows" that the argument is &gp.labels,
+		// because otherwise its write barrier behavior may not
+		// be correct. See the long comment there before
+		// changing the argument here.
+		cpuprof.log.write(&gp.labels, nanotime(), hdr[:], stk)
+	}
+
+	atomic.Store(&prof.signalLock, 0)
 }
 
-// addWithFlushlog implements add and addNonGo.
-// It is called from signal handlers and other limited environments
-// and cannot allocate memory or acquire locks that might be
-// held at the time of the signal, nor can it use substantial amounts
-// of stack. It may be called by a signal handler with no g or m.
-// It is allowed to call evict, passing the flushlog parameter.
+// addNonGo adds the non-Go stack trace to the profile.
+// It is called from a non-Go thread, so we cannot use much stack at all,
+// nor do anything that needs a g or an m.
+// In particular, we can't call cpuprof.log.write.
+// Instead, we copy the stack into cpuprof.extra,
+// which will be drained the next time a Go thread
+// gets the signal handling event.
 //go:nosplit
 //go:nowritebarrierrec
-func (p *cpuProfile) addWithFlushlog(pc []uintptr, flushlog func() bool) {
-	if len(pc) > maxCPUProfStack {
-		pc = pc[:maxCPUProfStack]
+func (p *cpuProfile) addNonGo(stk []uintptr) {
+	// Simple cas-lock to coordinate with SetCPUProfileRate.
+	// (Other calls to add or addNonGo should be blocked out
+	// by the fact that only one SIGPROF can be handled by the
+	// process at a time. If not, this lock will serialize those too.)
+	for !atomic.Cas(&prof.signalLock, 0, 1) {
+		osyield()
 	}
 
-	// Compute hash.
-	h := uintptr(0)
-	for _, x := range pc {
-		h = h<<8 | (h >> (8 * (unsafe.Sizeof(h) - 1)))
-		h += x * 41
-	}
-	p.count++
-
-	// Add to entry count if already present in table.
-	b := &p.hash[h%numBuckets]
-Assoc:
-	for i := range b.entry {
-		e := &b.entry[i]
-		if e.depth != len(pc) {
-			continue
-		}
-		for j := range pc {
-			if e.stack[j] != pc[j] {
-				continue Assoc
-			}
-		}
-		e.count++
-		return
+	if cpuprof.numExtra+1+len(stk) < len(cpuprof.extra) {
+		i := cpuprof.numExtra
+		cpuprof.extra[i] = uintptr(1 + len(stk))
+		copy(cpuprof.extra[i+1:], stk)
+		cpuprof.numExtra += 1 + len(stk)
+	} else {
+		cpuprof.lostExtra++
 	}
 
-	// Evict entry with smallest count.
-	var e *cpuprofEntry
-	for i := range b.entry {
-		if e == nil || b.entry[i].count < e.count {
-			e = &b.entry[i]
-		}
-	}
-	if e.count > 0 {
-		if !p.evict(e, flushlog) {
-			// Could not evict entry. Record lost stack.
-			p.lost++
-			return
-		}
-		p.evicts++
-	}
-
-	// Reuse the newly evicted entry.
-	e.depth = len(pc)
-	e.count = 1
-	copy(e.stack[:], pc)
+	atomic.Store(&prof.signalLock, 0)
 }
 
-// evict copies the given entry's data into the log, so that
-// the entry can be reused.  evict is called from add, which
-// is called from the profiling signal handler, so it must not
-// allocate memory or block, and it may be called with no g or m.
-// It is safe to call flushlog. evict returns true if the entry was
-// copied to the log, false if there was no room available.
-//go:nosplit
-//go:nowritebarrierrec
-func (p *cpuProfile) evict(e *cpuprofEntry, flushlog func() bool) bool {
-	d := e.depth
-	nslot := d + 2
-	log := &p.log[p.toggle]
-	if p.nlog+nslot > len(log) {
-		if !flushlog() {
-			return false
+// addExtra adds the "extra" profiling events,
+// queued by addNonGo, to the profile log.
+// addExtra is called either from a signal handler on a Go thread
+// or from an ordinary goroutine; either way it can use stack
+// and has a g. The world may be stopped, though.
+func (p *cpuProfile) addExtra() {
+	// Copy accumulated non-Go profile events.
+	hdr := [1]uint64{1}
+	for i := 0; i < p.numExtra; {
+		p.log.write(nil, 0, hdr[:], p.extra[i+1:i+int(p.extra[i])])
+		i += int(p.extra[i])
+	}
+	p.numExtra = 0
+
+	// Report any lost events.
+	if p.lostExtra > 0 {
+		hdr := [1]uint64{p.lostExtra}
+		lostStk := [2]uintptr{
+			funcPC(_LostExternalCode) + sys.PCQuantum,
+			funcPC(_ExternalCode) + sys.PCQuantum,
 		}
-		log = &p.log[p.toggle]
+		cpuprof.log.write(nil, 0, hdr[:], lostStk[:])
 	}
-
-	q := p.nlog
-	log[q] = e.count
-	q++
-	log[q] = uintptr(d)
-	q++
-	copy(log[q:], e.stack[:d])
-	q += d
-	p.nlog = q
-	e.count = 0
-	return true
 }
 
-// flushlog tries to flush the current log and switch to the other one.
-// flushlog is called from evict, called from add, called from the signal handler,
-// so it cannot allocate memory or block. It can try to swap logs with
-// the writing goroutine, as explained in the comment at the top of this file.
-//go:nowritebarrierrec
-func (p *cpuProfile) flushlog() bool {
-	if !atomic.Cas(&p.handoff, 0, uint32(p.nlog)) {
-		return false
+func (p *cpuProfile) addLostAtomic64(count uint64) {
+	hdr := [1]uint64{count}
+	lostStk := [2]uintptr{
+		funcPC(_LostSIGPROFDuringAtomic64) + sys.PCQuantum,
+		funcPC(_System) + sys.PCQuantum,
 	}
-	notewakeup(&p.wait)
-
-	p.toggle = 1 - p.toggle
-	log := &p.log[p.toggle]
-	q := 0
-	if p.lost > 0 {
-		lostPC := funcPC(lostProfileData)
-		log[0] = p.lost
-		log[1] = 1
-		log[2] = lostPC
-		q = 3
-		p.lost = 0
-	}
-	p.nlog = q
-	return true
+	cpuprof.log.write(nil, 0, hdr[:], lostStk[:])
 }
 
-// addNonGo is like add, but runs on a non-Go thread.
-// It can't do anything that might need a g or an m.
-// With this entry point, we don't try to flush the log when evicting an
-// old entry. Instead, we just drop the stack trace if we're out of space.
-//go:nosplit
-//go:nowritebarrierrec
-func (p *cpuProfile) addNonGo(pc []uintptr) {
-	p.addWithFlushlog(pc, func() bool { return false })
-}
-
-// getprofile blocks until the next block of profiling data is available
-// and returns it as a []byte. It is called from the writing goroutine.
-func (p *cpuProfile) getprofile() []byte {
-	if p == nil {
-		return nil
-	}
-
-	if p.wholding {
-		// Release previous log to signal handling side.
-		// Loop because we are racing against SetCPUProfileRate(0).
-		for {
-			n := p.handoff
-			if n == 0 {
-				print("runtime: phase error during cpu profile handoff\n")
-				return nil
-			}
-			if n&0x80000000 != 0 {
-				p.wtoggle = 1 - p.wtoggle
-				p.wholding = false
-				p.flushing = true
-				goto Flush
-			}
-			if atomic.Cas(&p.handoff, n, 0) {
-				break
-			}
-		}
-		p.wtoggle = 1 - p.wtoggle
-		p.wholding = false
-	}
-
-	if p.flushing {
-		goto Flush
-	}
-
-	if !p.on && p.handoff == 0 {
-		return nil
-	}
-
-	// Wait for new log.
-	notetsleepg(&p.wait, -1)
-	noteclear(&p.wait)
-
-	switch n := p.handoff; {
-	case n == 0:
-		print("runtime: phase error during cpu profile wait\n")
-		return nil
-	case n == 0x80000000:
-		p.flushing = true
-		goto Flush
-	default:
-		n &^= 0x80000000
-
-		// Return new log to caller.
-		p.wholding = true
-
-		return uintptrBytes(p.log[p.wtoggle][:n])
-	}
-
-	// In flush mode.
-	// Add is no longer being called. We own the log.
-	// Also, p.handoff is non-zero, so flushlog will return false.
-	// Evict the hash table into the log and return it.
-Flush:
-	for i := range p.hash {
-		b := &p.hash[i]
-		for j := range b.entry {
-			e := &b.entry[j]
-			if e.count > 0 && !p.evict(e, p.flushlog) {
-				// Filled the log. Stop the loop and return what we've got.
-				break Flush
-			}
-		}
-	}
-
-	// Return pending log data.
-	if p.nlog > 0 {
-		// Note that we're using toggle now, not wtoggle,
-		// because we're working on the log directly.
-		n := p.nlog
-		p.nlog = 0
-		return uintptrBytes(p.log[p.toggle][:n])
-	}
-
-	// Made it through the table without finding anything to log.
-	if !p.eodSent {
-		// We may not have space to append this to the partial log buf,
-		// so we always return a new slice for the end-of-data marker.
-		p.eodSent = true
-		return uintptrBytes(eod[:])
-	}
-
-	// Finally done. Clean up and return nil.
-	p.flushing = false
-	if !atomic.Cas(&p.handoff, p.handoff, 0) {
-		print("runtime: profile flush racing with something\n")
-	}
-	return nil
-}
-
-func uintptrBytes(p []uintptr) (ret []byte) {
-	pp := (*slice)(unsafe.Pointer(&p))
-	rp := (*slice)(unsafe.Pointer(&ret))
-
-	rp.array = pp.array
-	rp.len = pp.len * int(unsafe.Sizeof(p[0]))
-	rp.cap = rp.len
-
-	return
-}
-
-// CPUProfile returns the next chunk of binary CPU profiling stack trace data,
-// blocking until data is available. If profiling is turned off and all the profile
-// data accumulated while it was on has been returned, CPUProfile returns nil.
-// The caller must save the returned data before calling CPUProfile again.
+// CPUProfile panics.
+// It formerly provided raw access to chunks of
+// a pprof-format profile generated by the runtime.
+// The details of generating that format have changed,
+// so this functionality has been removed.
 //
-// Most clients should use the runtime/pprof package or
-// the testing package's -test.cpuprofile flag instead of calling
-// CPUProfile directly.
+// Deprecated: use the runtime/pprof package,
+// or the handlers in the net/http/pprof package,
+// or the testing package's -test.cpuprofile flag instead.
 func CPUProfile() []byte {
-	return cpuprof.getprofile()
+	panic("CPUProfile no longer available")
 }
 
 //go:linkname runtime_pprof_runtime_cyclesPerSecond runtime_pprof.runtime_cyclesPerSecond
 func runtime_pprof_runtime_cyclesPerSecond() int64 {
 	return tickspersecond()
 }
+
+// readProfile, provided to runtime/pprof, returns the next chunk of
+// binary CPU profiling stack trace data, blocking until data is available.
+// If profiling is turned off and all the profile data accumulated while it was
+// on has been returned, readProfile returns eof=true.
+// The caller must save the returned data and tags before calling readProfile again.
+//
+//go:linkname runtime_pprof_readProfile runtime_pprof.readProfile
+func runtime_pprof_readProfile() ([]uint64, []unsafe.Pointer, bool) {
+	lock(&cpuprof.lock)
+	log := cpuprof.log
+	unlock(&cpuprof.lock)
+	data, tags, eof := log.read(profBufBlocking)
+	if len(data) == 0 && eof {
+		lock(&cpuprof.lock)
+		cpuprof.log = nil
+		unlock(&cpuprof.lock)
+	}
+	return data, tags, eof
+}
diff --git a/libgo/go/runtime/crash_cgo_test.go b/libgo/go/runtime/crash_cgo_test.go
index b338df9..b798731 100644
--- a/libgo/go/runtime/crash_cgo_test.go
+++ b/libgo/go/runtime/crash_cgo_test.go
@@ -24,7 +24,10 @@
 }
 
 func TestCgoSignalDeadlock(t *testing.T) {
-	t.Parallel()
+	// Don't call t.Parallel, since too much work going on at the
+	// same time can cause the testprogcgo code to overrun its
+	// timeouts (issue #18598).
+
 	if testing.Short() && runtime.GOOS == "windows" {
 		t.Skip("Skipping in short mode") // takes up to 64 seconds
 	}
@@ -291,33 +294,43 @@
 
 	got, err := testEnv(exec.Command(exe, runArg)).CombinedOutput()
 	if err != nil {
+		if testenv.Builder() == "linux-amd64-alpine" {
+			// See Issue 18243 and Issue 19938.
+			t.Skipf("Skipping failing test on Alpine (golang.org/issue/18243). Ignoring error: %v", err)
+		}
 		t.Fatal(err)
 	}
 	fn := strings.TrimSpace(string(got))
 	defer os.Remove(fn)
 
-	cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-top", "-nodecount=1", exe, fn))
-
-	found := false
-	for i, e := range cmd.Env {
-		if strings.HasPrefix(e, "PPROF_TMPDIR=") {
-			cmd.Env[i] = "PPROF_TMPDIR=" + os.TempDir()
-			found = true
-			break
+	for try := 0; try < 2; try++ {
+		cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-top", "-nodecount=1"))
+		// Check that pprof works both with and without explicit executable on command line.
+		if try == 0 {
+			cmd.Args = append(cmd.Args, exe, fn)
+		} else {
+			cmd.Args = append(cmd.Args, fn)
 		}
-	}
-	if !found {
-		cmd.Env = append(cmd.Env, "PPROF_TMPDIR="+os.TempDir())
-	}
 
-	top, err := cmd.CombinedOutput()
-	t.Logf("%s", top)
-	if err != nil {
-		t.Fatal(err)
-	}
+		found := false
+		for i, e := range cmd.Env {
+			if strings.HasPrefix(e, "PPROF_TMPDIR=") {
+				cmd.Env[i] = "PPROF_TMPDIR=" + os.TempDir()
+				found = true
+				break
+			}
+		}
+		if !found {
+			cmd.Env = append(cmd.Env, "PPROF_TMPDIR="+os.TempDir())
+		}
 
-	if !bytes.Contains(top, []byte("cpuHog")) {
-		t.Error("missing cpuHog in pprof output")
+		top, err := cmd.CombinedOutput()
+		t.Logf("%s:\n%s", cmd.Args, top)
+		if err != nil {
+			t.Error(err)
+		} else if !bytes.Contains(top, []byte("cpuHog")) {
+			t.Error("missing cpuHog in pprof output")
+		}
 	}
 }
 
@@ -397,3 +410,16 @@
 		t.Errorf("expected %q got %s", want, got)
 	}
 }
+
+func TestCgoNumGoroutine(t *testing.T) {
+	switch runtime.GOOS {
+	case "windows", "plan9":
+		t.Skipf("skipping numgoroutine test on %s", runtime.GOOS)
+	}
+	t.Parallel()
+	got := runTestProg(t, "testprogcgo", "NumGoroutine")
+	want := "OK\n"
+	if got != want {
+		t.Errorf("expected %q got %v", want, got)
+	}
+}
diff --git a/libgo/go/runtime/crash_test.go b/libgo/go/runtime/crash_test.go
index 4ba9d44..1cde6bf 100644
--- a/libgo/go/runtime/crash_test.go
+++ b/libgo/go/runtime/crash_test.go
@@ -164,6 +164,12 @@
 			return
 		}
 		if string(out) != "false\n" {
+			t.Logf("go list -f {{.Stale}} runtime:\n%s", out)
+			out, err := testEnv(exec.Command(testenv.GoToolPath(t), "list", "-f", "{{.StaleReason}}", "runtime")).CombinedOutput()
+			if err != nil {
+				t.Logf("go list -f {{.StaleReason}} failed: %v", err)
+			}
+			t.Logf("go list -f {{.StaleReason}} runtime:\n%s", out)
 			staleRuntimeErr = fmt.Errorf("Stale runtime.a. Run 'go install runtime'.")
 		}
 	})
@@ -305,6 +311,9 @@
 
 func TestBreakpoint(t *testing.T) {
 	output := runTestProg(t, "testprog", "Breakpoint")
+	// If runtime.Breakpoint() is inlined, then the stack trace prints
+	// "runtime.Breakpoint(...)" instead of "runtime.Breakpoint()".
+	// For gccgo, no parens.
 	want := "runtime.Breakpoint"
 	if !strings.Contains(output, want) {
 		t.Fatalf("output:\n%s\n\nwant output containing: %s", output, want)
@@ -481,28 +490,33 @@
 	fn := strings.TrimSpace(string(got))
 	defer os.Remove(fn)
 
-	cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-alloc_space", "-top", exe, fn))
-
-	found := false
-	for i, e := range cmd.Env {
-		if strings.HasPrefix(e, "PPROF_TMPDIR=") {
-			cmd.Env[i] = "PPROF_TMPDIR=" + os.TempDir()
-			found = true
-			break
+	for try := 0; try < 2; try++ {
+		cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-alloc_space", "-top"))
+		// Check that pprof works both with and without explicit executable on command line.
+		if try == 0 {
+			cmd.Args = append(cmd.Args, exe, fn)
+		} else {
+			cmd.Args = append(cmd.Args, fn)
 		}
-	}
-	if !found {
-		cmd.Env = append(cmd.Env, "PPROF_TMPDIR="+os.TempDir())
-	}
+		found := false
+		for i, e := range cmd.Env {
+			if strings.HasPrefix(e, "PPROF_TMPDIR=") {
+				cmd.Env[i] = "PPROF_TMPDIR=" + os.TempDir()
+				found = true
+				break
+			}
+		}
+		if !found {
+			cmd.Env = append(cmd.Env, "PPROF_TMPDIR="+os.TempDir())
+		}
 
-	top, err := cmd.CombinedOutput()
-	t.Logf("%s", top)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if !bytes.Contains(top, []byte("MemProf")) {
-		t.Error("missing MemProf in pprof output")
+		top, err := cmd.CombinedOutput()
+		t.Logf("%s:\n%s", cmd.Args, top)
+		if err != nil {
+			t.Error(err)
+		} else if !bytes.Contains(top, []byte("MemProf")) {
+			t.Error("missing MemProf in pprof output")
+		}
 	}
 }
 
@@ -541,3 +555,87 @@
 		t.Fatalf("output does not start with %q:\n%s", want, output)
 	}
 }
+
+type point struct {
+	x, y *int
+}
+
+func (p *point) negate() {
+	*p.x = *p.x * -1
+	*p.y = *p.y * -1
+}
+
+// Test for issue #10152.
+func TestPanicInlined(t *testing.T) {
+	defer func() {
+		r := recover()
+		if r == nil {
+			t.Fatalf("recover failed")
+		}
+		buf := make([]byte, 2048)
+		n := runtime.Stack(buf, false)
+		buf = buf[:n]
+		want := []byte("(*point).negate(")
+		if runtime.Compiler == "gccgo" {
+			want = []byte("negate.pN18_runtime_test.point")
+		}
+		if !bytes.Contains(buf, want) {
+			t.Logf("%s", buf)
+			t.Fatalf("expecting stack trace to contain call to %s", want)
+		}
+	}()
+
+	pt := new(point)
+	pt.negate()
+}
+
+// Test for issues #3934 and #20018.
+// We want to delay exiting until a panic print is complete.
+func TestPanicRace(t *testing.T) {
+	testenv.MustHaveGoRun(t)
+
+	exe, err := buildTestProg(t, "testprog")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// The test is intentionally racy, and in my testing does not
+	// produce the expected output about 0.05% of the time.
+	// So run the program in a loop and only fail the test if we
+	// get the wrong output ten times in a row.
+	const tries = 10
+retry:
+	for i := 0; i < tries; i++ {
+		got, err := testEnv(exec.Command(exe, "PanicRace")).CombinedOutput()
+		if err == nil {
+			t.Logf("try %d: program exited successfully, should have failed", i+1)
+			continue
+		}
+
+		if i > 0 {
+			t.Logf("try %d:\n", i+1)
+		}
+		t.Logf("%s\n", got)
+
+		wants := []string{
+			"panic: crash",
+			"PanicRace",
+			"created by ",
+		}
+		if runtime.Compiler == "gccgo" {
+			// gccgo will dump a function name like main.$nested30.
+			// Match on the file name instead.
+			wants[1] = "panicrace"
+		}
+		for _, want := range wants {
+			if !bytes.Contains(got, []byte(want)) {
+				t.Logf("did not find expected string %q", want)
+				continue retry
+			}
+		}
+
+		// Test generated expected output.
+		return
+	}
+	t.Errorf("test ran %d times without producing expected output", tries)
+}
diff --git a/libgo/go/runtime/crash_unix_test.go b/libgo/go/runtime/crash_unix_test.go
index 7a29c1e..09c2547 100644
--- a/libgo/go/runtime/crash_unix_test.go
+++ b/libgo/go/runtime/crash_unix_test.go
@@ -24,6 +24,15 @@
 // Send SIGQUIT to get a stack trace.
 var sigquit = syscall.SIGQUIT
 
+func init() {
+	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
+		// We can't use SIGQUIT to kill subprocesses because
+		// it's blocked. Use SIGKILL instead. See issue
+		// #19196 for an example of when this happens.
+		sigquit = syscall.SIGKILL
+	}
+}
+
 func TestCrashDumpsAllThreads(t *testing.T) {
 	switch runtime.GOOS {
 	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
@@ -31,6 +40,10 @@
 		t.Skipf("skipping; not supported on %v", runtime.GOOS)
 	}
 
+	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
+		t.Skip("skipping; SIGQUIT is blocked, see golang.org/issue/19196")
+	}
+
 	// We don't use executeTest because we need to kill the
 	// program while it is running.
 
@@ -165,6 +178,10 @@
 		t.Skip("Skipping in short mode (GOTRACEBACK=crash is slow)")
 	}
 
+	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
+		t.Skip("skipping; SIGQUIT is blocked, see golang.org/issue/19196")
+	}
+
 	t.Parallel()
 	cmd := exec.Command(os.Args[0], "testPanicSystemstackInternal")
 	cmd = testEnv(cmd)
@@ -251,3 +268,16 @@
 		t.Fatalf("want %s, got %s\n", want, output)
 	}
 }
+
+func TestSignalDuringExec(t *testing.T) {
+	switch runtime.GOOS {
+	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd":
+	default:
+		t.Skipf("skipping test on %s", runtime.GOOS)
+	}
+	output := runTestProg(t, "testprognet", "SignalDuringExec")
+	want := "OK\n"
+	if output != want {
+		t.Fatalf("want %s, got %s\n", want, output)
+	}
+}
diff --git a/libgo/go/runtime/debug/garbage.go b/libgo/go/runtime/debug/garbage.go
index c82c024..785e9d4 100644
--- a/libgo/go/runtime/debug/garbage.go
+++ b/libgo/go/runtime/debug/garbage.go
@@ -89,9 +89,7 @@
 // at startup, or 100 if the variable is not set.
 // A negative percentage disables garbage collection.
 func SetGCPercent(percent int) int {
-	old := setGCPercent(int32(percent))
-	runtime.GC()
-	return int(old)
+	return int(setGCPercent(int32(percent)))
 }
 
 // FreeOSMemory forces a garbage collection followed by an
diff --git a/libgo/go/runtime/debug/garbage_test.go b/libgo/go/runtime/debug/garbage_test.go
index 04e954b..62eeb2c 100644
--- a/libgo/go/runtime/debug/garbage_test.go
+++ b/libgo/go/runtime/debug/garbage_test.go
@@ -5,6 +5,7 @@
 package debug_test
 
 import (
+	"internal/testenv"
 	"runtime"
 	. "runtime/debug"
 	"testing"
@@ -104,15 +105,78 @@
 	}
 }
 
+var (
+	setGCPercentBallast interface{}
+	setGCPercentSink    interface{}
+)
+
 func TestSetGCPercent(t *testing.T) {
+	testenv.SkipFlaky(t, 20076)
+
 	// Test that the variable is being set and returned correctly.
-	// Assume the percentage itself is implemented fine during GC,
-	// which is harder to test.
 	old := SetGCPercent(123)
 	new := SetGCPercent(old)
 	if new != 123 {
 		t.Errorf("SetGCPercent(123); SetGCPercent(x) = %d, want 123", new)
 	}
+
+	// Test that the percentage is implemented correctly.
+	defer func() {
+		SetGCPercent(old)
+		setGCPercentBallast, setGCPercentSink = nil, nil
+	}()
+	SetGCPercent(100)
+	runtime.GC()
+	// Create 100 MB of live heap as a baseline.
+	const baseline = 100 << 20
+	var ms runtime.MemStats
+	runtime.ReadMemStats(&ms)
+	setGCPercentBallast = make([]byte, baseline-ms.Alloc)
+	runtime.GC()
+	runtime.ReadMemStats(&ms)
+	if abs64(baseline-int64(ms.Alloc)) > 10<<20 {
+		t.Fatalf("failed to set up baseline live heap; got %d MB, want %d MB", ms.Alloc>>20, baseline>>20)
+	}
+	// NextGC should be ~200 MB.
+	const thresh = 20 << 20 // TODO: Figure out why this is so noisy on some builders
+	if want := int64(2 * baseline); abs64(want-int64(ms.NextGC)) > thresh {
+		t.Errorf("NextGC = %d MB, want %d±%d MB", ms.NextGC>>20, want>>20, thresh>>20)
+	}
+	// Create some garbage, but not enough to trigger another GC.
+	for i := 0; float64(i) < 1.2*baseline; i += 1 << 10 {
+		setGCPercentSink = make([]byte, 1<<10)
+	}
+	setGCPercentSink = nil
+	// Adjust GOGC to 50. NextGC should be ~150 MB.
+	SetGCPercent(50)
+	runtime.ReadMemStats(&ms)
+	if want := int64(1.5 * baseline); abs64(want-int64(ms.NextGC)) > thresh {
+		t.Errorf("NextGC = %d MB, want %d±%d MB", ms.NextGC>>20, want>>20, thresh>>20)
+	}
+
+	// Trigger a GC and get back to 100 MB live with GOGC=100.
+	SetGCPercent(100)
+	runtime.GC()
+	// Raise live to 120 MB.
+	setGCPercentSink = make([]byte, int(0.2*baseline))
+	// Lower GOGC to 10. This must force a GC.
+	runtime.ReadMemStats(&ms)
+	ngc1 := ms.NumGC
+	SetGCPercent(10)
+	// It may require an allocation to actually force the GC.
+	setGCPercentSink = make([]byte, 1<<20)
+	runtime.ReadMemStats(&ms)
+	ngc2 := ms.NumGC
+	if ngc1 == ngc2 {
+		t.Errorf("expected GC to run but it did not")
+	}
+}
+
+func abs64(a int64) int64 {
+	if a < 0 {
+		return -a
+	}
+	return a
 }
 
 func TestSetMaxThreadsOvf(t *testing.T) {
diff --git a/libgo/go/runtime/env_posix.go b/libgo/go/runtime/env_posix.go
index 9bf7ddc..ddf3c02 100644
--- a/libgo/go/runtime/env_posix.go
+++ b/libgo/go/runtime/env_posix.go
@@ -11,7 +11,7 @@
 	if env == nil {
 		throw("getenv before env init")
 	}
-	for _, s := range environ() {
+	for _, s := range env {
 		if len(s) > len(key) && s[len(key)] == '=' && s[:len(key)] == key {
 			return s[len(key)+1:]
 		}
diff --git a/libgo/go/runtime/error.go b/libgo/go/runtime/error.go
index 9cf2230..44e63d8 100644
--- a/libgo/go/runtime/error.go
+++ b/libgo/go/runtime/error.go
@@ -140,8 +140,6 @@
 
 // For calling from C.
 // Prints an argument passed to panic.
-// There's room for arbitrary complexity here, but we keep it
-// simple and handle just a few important cases: int, string, and Stringer.
 func printany(i interface{}) {
 	switch v := i.(type) {
 	case nil:
@@ -150,16 +148,41 @@
 		print(v.String())
 	case error:
 		print(v.Error())
+	case bool:
+		print(v)
 	case int:
 		print(v)
+	case int8:
+		print(v)
+	case int16:
+		print(v)
+	case int32:
+		print(v)
+	case int64:
+		print(v)
+	case uint:
+		print(v)
+	case uint8:
+		print(v)
+	case uint16:
+		print(v)
+	case uint32:
+		print(v)
+	case uint64:
+		print(v)
+	case uintptr:
+		print(v)
+	case float32:
+		print(v)
+	case float64:
+		print(v)
+	case complex64:
+		print(v)
+	case complex128:
+		print(v)
 	case string:
 		print(v)
 	default:
 		print("(", typestring(i), ") ", i)
 	}
 }
-
-// called from generated code
-func panicwrap(pkg, typ, meth string) {
-	panic(plainError("value method " + pkg + "." + typ + "." + meth + " called using nil *" + typ + " pointer"))
-}
diff --git a/libgo/go/runtime/example_test.go b/libgo/go/runtime/example_test.go
new file mode 100644
index 0000000..e4912a5
--- /dev/null
+++ b/libgo/go/runtime/example_test.go
@@ -0,0 +1,54 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime_test
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+)
+
+func ExampleFrames() {
+	c := func() {
+		// Ask runtime.Callers for up to 10 pcs, including runtime.Callers itself.
+		pc := make([]uintptr, 10)
+		n := runtime.Callers(0, pc)
+		if n == 0 {
+			// No pcs available. Stop now.
+			// This can happen if the first argument to runtime.Callers is large.
+			return
+		}
+
+		pc = pc[:n] // pass only valid pcs to runtime.CallersFrames
+		frames := runtime.CallersFrames(pc)
+
+		// Loop to get frames.
+		// A fixed number of pcs can expand to an indefinite number of Frames.
+		for {
+			frame, more := frames.Next()
+			// To keep this example's output stable
+			// even if there are changes in the testing package,
+			// stop unwinding when we leave package runtime.
+			if !strings.Contains(frame.File, "runtime/") {
+				break
+			}
+			fmt.Printf("- more:%v | %s\n", more, frame.Function)
+			if !more {
+				break
+			}
+		}
+	}
+
+	b := func() { c() }
+	a := func() { b() }
+
+	a()
+	// Output:
+	// - more:true | runtime.Callers
+	// - more:true | runtime_test.ExampleFrames.func1
+	// - more:true | runtime_test.ExampleFrames.func2
+	// - more:true | runtime_test.ExampleFrames.func3
+	// - more:true | runtime_test.ExampleFrames
+}
diff --git a/libgo/go/runtime/export_test.go b/libgo/go/runtime/export_test.go
index bf435f4..6325dcb 100644
--- a/libgo/go/runtime/export_test.go
+++ b/libgo/go/runtime/export_test.go
@@ -41,11 +41,11 @@
 }
 
 func LFStackPush(head *uint64, node *LFNode) {
-	lfstackpush(head, (*lfnode)(unsafe.Pointer(node)))
+	(*lfstack)(head).push((*lfnode)(unsafe.Pointer(node)))
 }
 
 func LFStackPop(head *uint64) *LFNode {
-	return (*LFNode)(unsafe.Pointer(lfstackpop(head)))
+	return (*LFNode)(unsafe.Pointer((*lfstack)(head).pop()))
 }
 
 func GCMask(x interface{}) (ret []byte) {
@@ -241,6 +241,97 @@
 	return
 }
 
+func Fastrand() uint32          { return fastrand() }
+func Fastrandn(n uint32) uint32 { return fastrandn(n) }
+
+type ProfBuf profBuf
+
+func NewProfBuf(hdrsize, bufwords, tags int) *ProfBuf {
+	return (*ProfBuf)(newProfBuf(hdrsize, bufwords, tags))
+}
+
+func (p *ProfBuf) Write(tag *unsafe.Pointer, now int64, hdr []uint64, stk []uintptr) {
+	(*profBuf)(p).write(tag, now, hdr, stk)
+}
+
+const (
+	ProfBufBlocking    = profBufBlocking
+	ProfBufNonBlocking = profBufNonBlocking
+)
+
+func (p *ProfBuf) Read(mode profBufReadMode) ([]uint64, []unsafe.Pointer, bool) {
+	return (*profBuf)(p).read(profBufReadMode(mode))
+}
+
+func (p *ProfBuf) Close() {
+	(*profBuf)(p).close()
+}
+
+// ReadMemStatsSlow returns both the runtime-computed MemStats and
+// MemStats accumulated by scanning the heap.
+func ReadMemStatsSlow() (base, slow MemStats) {
+	stopTheWorld("ReadMemStatsSlow")
+
+	// Run on the system stack to avoid stack growth allocation.
+	systemstack(func() {
+		// Make sure stats don't change.
+		getg().m.mallocing++
+
+		readmemstats_m(&base)
+
+		// Initialize slow from base and zero the fields we're
+		// recomputing.
+		slow = base
+		slow.Alloc = 0
+		slow.TotalAlloc = 0
+		slow.Mallocs = 0
+		slow.Frees = 0
+		var bySize [_NumSizeClasses]struct {
+			Mallocs, Frees uint64
+		}
+
+		// Add up current allocations in spans.
+		for _, s := range mheap_.allspans {
+			if s.state != mSpanInUse {
+				continue
+			}
+			if sizeclass := s.spanclass.sizeclass(); sizeclass == 0 {
+				slow.Mallocs++
+				slow.Alloc += uint64(s.elemsize)
+			} else {
+				slow.Mallocs += uint64(s.allocCount)
+				slow.Alloc += uint64(s.allocCount) * uint64(s.elemsize)
+				bySize[sizeclass].Mallocs += uint64(s.allocCount)
+			}
+		}
+
+		// Add in frees. readmemstats_m flushed the cached stats, so
+		// these are up-to-date.
+		var smallFree uint64
+		slow.Frees = mheap_.nlargefree
+		for i := range mheap_.nsmallfree {
+			slow.Frees += mheap_.nsmallfree[i]
+			bySize[i].Frees = mheap_.nsmallfree[i]
+			bySize[i].Mallocs += mheap_.nsmallfree[i]
+			smallFree += mheap_.nsmallfree[i] * uint64(class_to_size[i])
+		}
+		slow.Frees += memstats.tinyallocs
+		slow.Mallocs += slow.Frees
+
+		slow.TotalAlloc = slow.Alloc + mheap_.largefree + smallFree
+
+		for i := range slow.BySize {
+			slow.BySize[i].Mallocs = bySize[i].Mallocs
+			slow.BySize[i].Frees = bySize[i].Frees
+		}
+
+		getg().m.mallocing--
+	})
+
+	startTheWorld()
+	return
+}
+
 // BlockOnSystemStack switches to the system stack, prints "x\n" to
 // stderr, and blocks in a stack containing
 // "runtime.blockOnSystemStackInternal".
@@ -253,3 +344,23 @@
 	lock(&deadlock)
 	lock(&deadlock)
 }
+
+type RWMutex struct {
+	rw rwmutex
+}
+
+func (rw *RWMutex) RLock() {
+	rw.rw.rlock()
+}
+
+func (rw *RWMutex) RUnlock() {
+	rw.rw.runlock()
+}
+
+func (rw *RWMutex) Lock() {
+	rw.rw.lock()
+}
+
+func (rw *RWMutex) Unlock() {
+	rw.rw.unlock()
+}
diff --git a/libgo/go/runtime/export_unix_test.go b/libgo/go/runtime/export_unix_test.go
new file mode 100644
index 0000000..54d5770
--- /dev/null
+++ b/libgo/go/runtime/export_unix_test.go
@@ -0,0 +1,19 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package runtime
+
+func sigismember(mask *sigset, i int) bool {
+	clear := *mask
+	sigdelset(&clear, i)
+	return clear != *mask
+}
+
+func Sigisblocked(i int) bool {
+	var sigmask sigset
+	sigprocmask(_SIG_SETMASK, nil, &sigmask)
+	return sigismember(&sigmask, i)
+}
diff --git a/libgo/go/runtime/extern.go b/libgo/go/runtime/extern.go
index 5c50760..6ca9789 100644
--- a/libgo/go/runtime/extern.go
+++ b/libgo/go/runtime/extern.go
@@ -50,13 +50,6 @@
 	gcshrinkstackoff: setting gcshrinkstackoff=1 disables moving goroutines
 	onto smaller stacks. In this mode, a goroutine's stack can only grow.
 
-	gcstackbarrieroff: setting gcstackbarrieroff=1 disables the use of stack barriers
-	that allow the garbage collector to avoid repeating a stack scan during the
-	mark termination phase.
-
-	gcstackbarrierall: setting gcstackbarrierall=1 installs stack barriers
-	in every stack frame, rather than in exponentially-spaced frames.
-
 	gcrescanstacks: setting gcrescanstacks=1 enables stack
 	re-scanning during the STW mark termination phase. This is
 	helpful for debugging if objects are being prematurely
@@ -85,7 +78,7 @@
 	for mark/scan are broken down in to assist time (GC performed in
 	line with allocation), background GC time, and idle GC time.
 	If the line ends with "(forced)", this GC was forced by a
-	runtime.GC() call and all phases are STW.
+	runtime.GC() call.
 
 	Setting gctrace to any value > 0 also causes the garbage collector
 	to emit a summary when memory is released back to the system.
@@ -173,7 +166,7 @@
 // to ascend, with 0 identifying the caller of Caller.  (For historical reasons the
 // meaning of skip differs between Caller and Callers.) The return values report the
 // program counter, file name, and line number within the file of the corresponding
-// call.  The boolean ok is false if it was not possible to recover the information.
+// call. The boolean ok is false if it was not possible to recover the information.
 func Caller(skip int) (pc uintptr, file string, line int, ok bool)
 
 // Callers fills the slice pc with the return program counters of function invocations
@@ -181,6 +174,14 @@
 // to skip before recording in pc, with 0 identifying the frame for Callers itself and
 // 1 identifying the caller of Callers.
 // It returns the number of entries written to pc.
+//
+// To translate these PCs into symbolic information such as function
+// names and line numbers, use CallersFrames. CallersFrames accounts
+// for inlined functions and adjusts the return program counters into
+// call program counters. Iterating over the returned slice of PCs
+// directly is discouraged, as is using FuncForPC on any of the
+// returned PCs, since these cannot account for inlining or return
+// program counter adjustment.
 func Callers(skip int, pc []uintptr) int
 
 // GOROOT returns the root of the Go tree.
@@ -206,7 +207,7 @@
 const GOOS string = sys.GOOS
 
 // GOARCH is the running program's architecture target:
-// 386, amd64, arm, or s390x.
+// one of 386, amd64, arm, s390x, and so on.
 const GOARCH string = sys.GOARCH
 
 // GCCGOTOOLDIR is the Tool Dir for the gccgo build
diff --git a/libgo/go/runtime/fastlog2.go b/libgo/go/runtime/fastlog2.go
index 5f3fb53..1f251bf 100644
--- a/libgo/go/runtime/fastlog2.go
+++ b/libgo/go/runtime/fastlog2.go
@@ -4,8 +4,6 @@
 
 package runtime
 
-import "unsafe"
-
 // fastlog2 implements a fast approximation to the base 2 log of a
 // float64. This is used to compute a geometric distribution for heap
 // sampling, without introducing dependencies into package math. This
@@ -27,7 +25,3 @@
 	low, high := fastlog2Table[xManIndex], fastlog2Table[xManIndex+1]
 	return float64(xExp) + low + (high-low)*float64(xManScale)*fastlogScaleRatio
 }
-
-// float64bits returns the IEEE 754 binary representation of f.
-// Taken from math.Float64bits to avoid dependencies into package math.
-func float64bits(f float64) uint64 { return *(*uint64)(unsafe.Pointer(&f)) }
diff --git a/libgo/go/runtime/float.go b/libgo/go/runtime/float.go
new file mode 100644
index 0000000..459e58d
--- /dev/null
+++ b/libgo/go/runtime/float.go
@@ -0,0 +1,53 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+var inf = float64frombits(0x7FF0000000000000)
+
+// isNaN reports whether f is an IEEE 754 ``not-a-number'' value.
+func isNaN(f float64) (is bool) {
+	// IEEE 754 says that only NaNs satisfy f != f.
+	return f != f
+}
+
+// isFinite reports whether f is neither NaN nor an infinity.
+func isFinite(f float64) bool {
+	return !isNaN(f - f)
+}
+
+// isInf reports whether f is an infinity.
+func isInf(f float64) bool {
+	return !isNaN(f) && !isFinite(f)
+}
+
+// Abs returns the absolute value of x.
+//
+// Special cases are:
+//	Abs(±Inf) = +Inf
+//	Abs(NaN) = NaN
+func abs(x float64) float64 {
+	const sign = 1 << 63
+	return float64frombits(float64bits(x) &^ sign)
+}
+
+// copysign returns a value with the magnitude
+// of x and the sign of y.
+func copysign(x, y float64) float64 {
+	const sign = 1 << 63
+	return float64frombits(float64bits(x)&^sign | float64bits(y)&sign)
+}
+
+// Float64bits returns the IEEE 754 binary representation of f.
+func float64bits(f float64) uint64 {
+	return *(*uint64)(unsafe.Pointer(&f))
+}
+
+// Float64frombits returns the floating point number corresponding
+// the IEEE 754 binary representation b.
+func float64frombits(b uint64) float64 {
+	return *(*float64)(unsafe.Pointer(&b))
+}
diff --git a/libgo/go/runtime/gc_test.go b/libgo/go/runtime/gc_test.go
index ec043ed..f14e0d5 100644
--- a/libgo/go/runtime/gc_test.go
+++ b/libgo/go/runtime/gc_test.go
@@ -5,6 +5,7 @@
 package runtime_test
 
 import (
+	"fmt"
 	"os"
 	"reflect"
 	"runtime"
@@ -450,3 +451,53 @@
 		t.Fatalf("mheap_.pagesInUse is %d, but direct count is %d", pagesInUse, counted)
 	}
 }
+
+func TestReadMemStats(t *testing.T) {
+	base, slow := runtime.ReadMemStatsSlow()
+	if base != slow {
+		logDiff(t, "MemStats", reflect.ValueOf(base), reflect.ValueOf(slow))
+		t.Fatal("memstats mismatch")
+	}
+}
+
+func logDiff(t *testing.T, prefix string, got, want reflect.Value) {
+	typ := got.Type()
+	switch typ.Kind() {
+	case reflect.Array, reflect.Slice:
+		if got.Len() != want.Len() {
+			t.Logf("len(%s): got %v, want %v", prefix, got, want)
+			return
+		}
+		for i := 0; i < got.Len(); i++ {
+			logDiff(t, fmt.Sprintf("%s[%d]", prefix, i), got.Index(i), want.Index(i))
+		}
+	case reflect.Struct:
+		for i := 0; i < typ.NumField(); i++ {
+			gf, wf := got.Field(i), want.Field(i)
+			logDiff(t, prefix+"."+typ.Field(i).Name, gf, wf)
+		}
+	case reflect.Map:
+		t.Fatal("not implemented: logDiff for map")
+	default:
+		if got.Interface() != want.Interface() {
+			t.Logf("%s: got %v, want %v", prefix, got, want)
+		}
+	}
+}
+
+func BenchmarkReadMemStats(b *testing.B) {
+	var ms runtime.MemStats
+	const heapSize = 100 << 20
+	x := make([]*[1024]byte, heapSize/1024)
+	for i := range x {
+		x[i] = new([1024]byte)
+	}
+	hugeSink = x
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		runtime.ReadMemStats(&ms)
+	}
+
+	hugeSink = nil
+}
diff --git a/libgo/go/runtime/hashmap.go b/libgo/go/runtime/hashmap.go
index 5b191d4..a3e50cd 100644
--- a/libgo/go/runtime/hashmap.go
+++ b/libgo/go/runtime/hashmap.go
@@ -129,6 +129,11 @@
 	oldbuckets unsafe.Pointer // previous bucket array of half the size, non-nil only when growing
 	nevacuate  uintptr        // progress counter for evacuation (buckets less than this have been evacuated)
 
+	extra *mapextra // optional fields
+}
+
+// mapextra holds fields that are not present on all maps.
+type mapextra struct {
 	// If both key and value do not contain pointers and are inline, then we mark bucket
 	// type as containing no pointers. This avoids scanning such maps.
 	// However, bmap.overflow is a pointer. In order to keep overflow buckets
@@ -136,9 +141,11 @@
 	// Overflow is used only if key and value do not contain pointers.
 	// overflow[0] contains overflow buckets for hmap.buckets.
 	// overflow[1] contains overflow buckets for hmap.oldbuckets.
-	// The first indirection allows us to reduce static size of hmap.
-	// The second indirection allows to store a pointer to the slice in hiter.
-	overflow *[2]*[]*bmap
+	// The indirection allows to store a pointer to the slice in hiter.
+	overflow [2]*[]*bmap
+
+	// nextOverflow holds a pointer to a free overflow bucket.
+	nextOverflow *bmap
 }
 
 // A bucket for a Go map.
@@ -183,6 +190,10 @@
 	return *(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-sys.PtrSize))
 }
 
+func (b *bmap) setoverflow(t *maptype, ovf *bmap) {
+	*(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-sys.PtrSize)) = ovf
+}
+
 // incrnoverflow increments h.noverflow.
 // noverflow counts the number of overflow buckets.
 // This is used to trigger same-size map growth.
@@ -209,21 +220,40 @@
 	}
 }
 
-func (h *hmap) setoverflow(t *maptype, b, ovf *bmap) {
+func (h *hmap) newoverflow(t *maptype, b *bmap) *bmap {
+	var ovf *bmap
+	if h.extra != nil && h.extra.nextOverflow != nil {
+		// We have preallocated overflow buckets available.
+		// See makeBucketArray for more details.
+		ovf = h.extra.nextOverflow
+		if ovf.overflow(t) == nil {
+			// We're not at the end of the preallocated overflow buckets. Bump the pointer.
+			h.extra.nextOverflow = (*bmap)(add(unsafe.Pointer(ovf), uintptr(t.bucketsize)))
+		} else {
+			// This is the last preallocated overflow bucket.
+			// Reset the overflow pointer on this bucket,
+			// which was set to a non-nil sentinel value.
+			ovf.setoverflow(t, nil)
+			h.extra.nextOverflow = nil
+		}
+	} else {
+		ovf = (*bmap)(newobject(t.bucket))
+	}
 	h.incrnoverflow()
 	if t.bucket.kind&kindNoPointers != 0 {
 		h.createOverflow()
-		*h.overflow[0] = append(*h.overflow[0], ovf)
+		*h.extra.overflow[0] = append(*h.extra.overflow[0], ovf)
 	}
-	*(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-sys.PtrSize)) = ovf
+	b.setoverflow(t, ovf)
+	return ovf
 }
 
 func (h *hmap) createOverflow() {
-	if h.overflow == nil {
-		h.overflow = new([2]*[]*bmap)
+	if h.extra == nil {
+		h.extra = new(mapextra)
 	}
-	if h.overflow[0] == nil {
-		h.overflow[0] = new([]*bmap)
+	if h.extra.overflow[0] == nil {
+		h.extra.overflow[0] = new([]*bmap)
 	}
 }
 
@@ -238,9 +268,8 @@
 		throw("bad hmap size")
 	}
 
-	if hint < 0 || int64(int32(hint)) != hint {
-		panic(plainError("makemap: size out of range"))
-		// TODO: make hint an int, then none of this nonsense
+	if hint < 0 || hint > int64(maxSliceCap(t.bucket.size)) {
+		hint = 0
 	}
 
 	if !ismapkey(t.key) {
@@ -290,8 +319,14 @@
 	// if B == 0, the buckets field is allocated lazily later (in mapassign)
 	// If hint is large zeroing this memory could take a while.
 	buckets := bucket
+	var extra *mapextra
 	if B != 0 {
-		buckets = newarray(t.bucket, 1<<B)
+		var nextOverflow *bmap
+		buckets, nextOverflow = makeBucketArray(t, B)
+		if nextOverflow != nil {
+			extra = new(mapextra)
+			extra.nextOverflow = nextOverflow
+		}
 	}
 
 	// initialize Hmap
@@ -300,6 +335,7 @@
 	}
 	h.count = 0
 	h.B = B
+	h.extra = extra
 	h.flags = 0
 	h.hash0 = fastrand()
 	h.buckets = buckets
@@ -514,12 +550,14 @@
 	if h.flags&hashWriting != 0 {
 		throw("concurrent map writes")
 	}
-	h.flags |= hashWriting
-
 	hashfn := t.key.hashfn
 	equalfn := t.key.equalfn
 	hash := hashfn(key, uintptr(h.hash0))
 
+	// Set hashWriting after calling alg.hash, since alg.hash may panic,
+	// in which case we have not actually done a write.
+	h.flags |= hashWriting
+
 	if h.buckets == nil {
 		h.buckets = newarray(t.bucket, 1)
 	}
@@ -580,8 +618,7 @@
 
 	if inserti == nil {
 		// all current buckets are full, allocate a new one.
-		newb := (*bmap)(newobject(t.bucket))
-		h.setoverflow(t, b, newb)
+		newb := h.newoverflow(t, b)
 		inserti = &newb.tophash[0]
 		insertk = add(unsafe.Pointer(newb), dataOffset)
 		val = add(insertk, bucketCnt*uintptr(t.keysize))
@@ -628,11 +665,15 @@
 	if h.flags&hashWriting != 0 {
 		throw("concurrent map writes")
 	}
-	h.flags |= hashWriting
 
 	hashfn := t.key.hashfn
 	equalfn := t.key.equalfn
 	hash := hashfn(key, uintptr(h.hash0))
+
+	// Set hashWriting after calling alg.hash, since alg.hash may panic,
+	// in which case we have not actually done a write (delete).
+	h.flags |= hashWriting
+
 	bucket := hash & (uintptr(1)<<h.B - 1)
 	if h.growing() {
 		growWork(t, h, bucket)
@@ -720,7 +761,7 @@
 		// the table grows and/or overflow buckets are added to the table
 		// while we are iterating.
 		h.createOverflow()
-		it.overflow = *h.overflow
+		it.overflow = h.extra.overflow
 	}
 
 	// decide where to start
@@ -886,6 +927,36 @@
 	goto next
 }
 
+func makeBucketArray(t *maptype, b uint8) (buckets unsafe.Pointer, nextOverflow *bmap) {
+	base := uintptr(1 << b)
+	nbuckets := base
+	// For small b, overflow buckets are unlikely.
+	// Avoid the overhead of the calculation.
+	if b >= 4 {
+		// Add on the estimated number of overflow buckets
+		// required to insert the median number of elements
+		// used with this value of b.
+		nbuckets += 1 << (b - 4)
+		sz := t.bucket.size * nbuckets
+		up := roundupsize(sz)
+		if up != sz {
+			nbuckets = up / t.bucket.size
+		}
+	}
+	buckets = newarray(t.bucket, int(nbuckets))
+	if base != nbuckets {
+		// We preallocated some overflow buckets.
+		// To keep the overhead of tracking these overflow buckets to a minimum,
+		// we use the convention that if a preallocated overflow bucket's overflow
+		// pointer is nil, then there are more available by bumping the pointer.
+		// We need a safe non-nil pointer for the last overflow bucket; just use buckets.
+		nextOverflow = (*bmap)(add(buckets, base*uintptr(t.bucketsize)))
+		last := (*bmap)(add(buckets, (nbuckets-1)*uintptr(t.bucketsize)))
+		last.setoverflow(t, (*bmap)(buckets))
+	}
+	return buckets, nextOverflow
+}
+
 func hashGrow(t *maptype, h *hmap) {
 	// If we've hit the load factor, get bigger.
 	// Otherwise, there are too many overflow buckets,
@@ -896,7 +967,8 @@
 		h.flags |= sameSizeGrow
 	}
 	oldbuckets := h.buckets
-	newbuckets := newarray(t.bucket, 1<<(h.B+bigger))
+	newbuckets, nextOverflow := makeBucketArray(t, h.B+bigger)
+
 	flags := h.flags &^ (iterator | oldIterator)
 	if h.flags&iterator != 0 {
 		flags |= oldIterator
@@ -909,13 +981,19 @@
 	h.nevacuate = 0
 	h.noverflow = 0
 
-	if h.overflow != nil {
+	if h.extra != nil && h.extra.overflow[0] != nil {
 		// Promote current overflow buckets to the old generation.
-		if h.overflow[1] != nil {
+		if h.extra.overflow[1] != nil {
 			throw("overflow is not nil")
 		}
-		h.overflow[1] = h.overflow[0]
-		h.overflow[0] = nil
+		h.extra.overflow[1] = h.extra.overflow[0]
+		h.extra.overflow[0] = nil
+	}
+	if nextOverflow != nil {
+		if h.extra == nil {
+			h.extra = new(mapextra)
+		}
+		h.extra.nextOverflow = nextOverflow
 	}
 
 	// the actual copying of the hash table data is done incrementally
@@ -925,7 +1003,7 @@
 // overLoadFactor reports whether count items placed in 1<<B buckets is over loadFactor.
 func overLoadFactor(count int64, B uint8) bool {
 	// TODO: rewrite to use integer math and comparison?
-	return count >= bucketCnt && float32(count) >= loadFactor*float32((uintptr(1)<<B))
+	return count >= bucketCnt && float32(count) >= loadFactor*float32((uint64(1)<<B))
 }
 
 // tooManyOverflowBuckets reports whether noverflow buckets is too many for a map with 1<<B buckets.
@@ -977,6 +1055,11 @@
 	}
 }
 
+func bucketEvacuated(t *maptype, h *hmap, bucket uintptr) bool {
+	b := (*bmap)(add(h.oldbuckets, bucket*uintptr(t.bucketsize)))
+	return evacuated(b)
+}
+
 func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
 	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
 	newbit := h.noldbuckets()
@@ -1054,8 +1137,7 @@
 				if useX {
 					b.tophash[i] = evacuatedX
 					if xi == bucketCnt {
-						newx := (*bmap)(newobject(t.bucket))
-						h.setoverflow(t, x, newx)
+						newx := h.newoverflow(t, x)
 						x = newx
 						xi = 0
 						xk = add(unsafe.Pointer(x), dataOffset)
@@ -1078,8 +1160,7 @@
 				} else {
 					b.tophash[i] = evacuatedY
 					if yi == bucketCnt {
-						newy := (*bmap)(newobject(t.bucket))
-						h.setoverflow(t, y, newy)
+						newy := h.newoverflow(t, y)
 						y = newy
 						yi = 0
 						yk = add(unsafe.Pointer(y), dataOffset)
@@ -1118,14 +1199,23 @@
 	// Advance evacuation mark
 	if oldbucket == h.nevacuate {
 		h.nevacuate = oldbucket + 1
-		if oldbucket+1 == newbit { // newbit == # of oldbuckets
+		// Experiments suggest that 1024 is overkill by at least an order of magnitude.
+		// Put it in there as a safeguard anyway, to ensure O(1) behavior.
+		stop := h.nevacuate + 1024
+		if stop > newbit {
+			stop = newbit
+		}
+		for h.nevacuate != stop && bucketEvacuated(t, h, h.nevacuate) {
+			h.nevacuate++
+		}
+		if h.nevacuate == newbit { // newbit == # of oldbuckets
 			// Growing is all done. Free old main bucket array.
 			h.oldbuckets = nil
 			// Can discard old overflow buckets as well.
 			// If they are still referenced by an iterator,
 			// then the iterator holds a pointers to the slice.
-			if h.overflow != nil {
-				h.overflow[1] = nil
+			if h.extra != nil {
+				h.extra.overflow[1] = nil
 			}
 			h.flags &^= sameSizeGrow
 		}
@@ -1139,8 +1229,8 @@
 // Reflect stubs. Called from ../reflect/asm_*.s
 
 //go:linkname reflect_makemap reflect.makemap
-func reflect_makemap(t *maptype) *hmap {
-	return makemap(t, 0, nil, nil)
+func reflect_makemap(t *maptype, cap int) *hmap {
+	return makemap(t, int64(cap), nil, nil)
 }
 
 //go:linkname reflect_mapaccess reflect.mapaccess
diff --git a/libgo/go/runtime/hashmap_fast.go b/libgo/go/runtime/hashmap_fast.go
index 853da70..bec8fda 100644
--- a/libgo/go/runtime/hashmap_fast.go
+++ b/libgo/go/runtime/hashmap_fast.go
@@ -45,7 +45,7 @@
 			if k != key {
 				continue
 			}
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x == empty {
 				continue
 			}
@@ -94,7 +94,7 @@
 			if k != key {
 				continue
 			}
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x == empty {
 				continue
 			}
@@ -143,7 +143,7 @@
 			if k != key {
 				continue
 			}
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x == empty {
 				continue
 			}
@@ -192,7 +192,7 @@
 			if k != key {
 				continue
 			}
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x == empty {
 				continue
 			}
@@ -223,7 +223,7 @@
 		if key.len < 32 {
 			// short key, doing lots of comparisons is ok
 			for i := uintptr(0); i < bucketCnt; i++ {
-				x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+				x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 				if x == empty {
 					continue
 				}
@@ -240,7 +240,7 @@
 		// long key, try not to do more comparisons than necessary
 		keymaybe := uintptr(bucketCnt)
 		for i := uintptr(0); i < bucketCnt; i++ {
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x == empty {
 				continue
 			}
@@ -252,8 +252,6 @@
 				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*sys.PtrSize+i*uintptr(t.valuesize))
 			}
 			// check first 4 bytes
-			// TODO: on amd64/386 at least, make this compile to one 4-byte comparison instead of
-			// four 1-byte comparisons.
 			if *((*[4]byte)(key.str)) != *((*[4]byte)(k.str)) {
 				continue
 			}
@@ -295,7 +293,7 @@
 	}
 	for {
 		for i := uintptr(0); i < bucketCnt; i++ {
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x != top {
 				continue
 			}
@@ -332,7 +330,7 @@
 		if key.len < 32 {
 			// short key, doing lots of comparisons is ok
 			for i := uintptr(0); i < bucketCnt; i++ {
-				x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+				x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 				if x == empty {
 					continue
 				}
@@ -349,7 +347,7 @@
 		// long key, try not to do more comparisons than necessary
 		keymaybe := uintptr(bucketCnt)
 		for i := uintptr(0); i < bucketCnt; i++ {
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x == empty {
 				continue
 			}
@@ -402,7 +400,7 @@
 	}
 	for {
 		for i := uintptr(0); i < bucketCnt; i++ {
-			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.topbits[i] without the bounds check
+			x := *((*uint8)(add(unsafe.Pointer(b), i))) // b.tophash[i] without the bounds check
 			if x != top {
 				continue
 			}
@@ -420,3 +418,441 @@
 		}
 	}
 }
+
+func mapassign_fast32(t *maptype, h *hmap, key uint32) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc(unsafe.Pointer(&t))
+		racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapassign_fast32))
+	}
+	if h.flags&hashWriting != 0 {
+		throw("concurrent map writes")
+	}
+	hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling alg.hash for consistency with mapassign.
+	h.flags |= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & (uintptr(1)<<h.B - 1)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
+	top := uint8(hash >> (sys.PtrSize*8 - 8))
+	if top < minTopHash {
+		top += minTopHash
+	}
+
+	var inserti *uint8
+	var insertk unsafe.Pointer
+	var val unsafe.Pointer
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if b.tophash[i] == empty && inserti == nil {
+					inserti = &b.tophash[i]
+					insertk = add(unsafe.Pointer(b), dataOffset+i*4)
+					val = add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.valuesize))
+				}
+				continue
+			}
+			k := *((*uint32)(add(unsafe.Pointer(b), dataOffset+i*4)))
+			if k != key {
+				continue
+			}
+			val = add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.valuesize))
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(int64(h.count), h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if inserti == nil {
+		// all current buckets are full, allocate a new one.
+		newb := h.newoverflow(t, b)
+		inserti = &newb.tophash[0]
+		insertk = add(unsafe.Pointer(newb), dataOffset)
+		val = add(insertk, bucketCnt*4)
+	}
+
+	// store new key/value at insert position
+	typedmemmove(t.key, insertk, unsafe.Pointer(&key))
+	*inserti = top
+	h.count++
+
+done:
+	if h.flags&hashWriting == 0 {
+		throw("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return val
+}
+
+func mapassign_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc(unsafe.Pointer(&t))
+		racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapassign_fast64))
+	}
+	if h.flags&hashWriting != 0 {
+		throw("concurrent map writes")
+	}
+	hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling alg.hash for consistency with mapassign.
+	h.flags |= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & (uintptr(1)<<h.B - 1)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
+	top := uint8(hash >> (sys.PtrSize*8 - 8))
+	if top < minTopHash {
+		top += minTopHash
+	}
+
+	var inserti *uint8
+	var insertk unsafe.Pointer
+	var val unsafe.Pointer
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if b.tophash[i] == empty && inserti == nil {
+					inserti = &b.tophash[i]
+					insertk = add(unsafe.Pointer(b), dataOffset+i*8)
+					val = add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.valuesize))
+				}
+				continue
+			}
+			k := *((*uint64)(add(unsafe.Pointer(b), dataOffset+i*8)))
+			if k != key {
+				continue
+			}
+			val = add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.valuesize))
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(int64(h.count), h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if inserti == nil {
+		// all current buckets are full, allocate a new one.
+		newb := h.newoverflow(t, b)
+		inserti = &newb.tophash[0]
+		insertk = add(unsafe.Pointer(newb), dataOffset)
+		val = add(insertk, bucketCnt*8)
+	}
+
+	// store new key/value at insert position
+	typedmemmove(t.key, insertk, unsafe.Pointer(&key))
+	*inserti = top
+	h.count++
+
+done:
+	if h.flags&hashWriting == 0 {
+		throw("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return val
+}
+
+func mapassign_faststr(t *maptype, h *hmap, ky string) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc(unsafe.Pointer(&t))
+		racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapassign_faststr))
+	}
+	if h.flags&hashWriting != 0 {
+		throw("concurrent map writes")
+	}
+	key := stringStructOf(&ky)
+	hash := t.key.hashfn(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
+
+	// Set hashWriting after calling alg.hash for consistency with mapassign.
+	h.flags |= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & (uintptr(1)<<h.B - 1)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
+	top := uint8(hash >> (sys.PtrSize*8 - 8))
+	if top < minTopHash {
+		top += minTopHash
+	}
+
+	var inserti *uint8
+	var insertk unsafe.Pointer
+	var val unsafe.Pointer
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if b.tophash[i] == empty && inserti == nil {
+					inserti = &b.tophash[i]
+					insertk = add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
+					val = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.valuesize))
+				}
+				continue
+			}
+			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+i*2*sys.PtrSize))
+			if k.len != key.len {
+				continue
+			}
+			if k.str != key.str && !memequal(k.str, key.str, uintptr(key.len)) {
+				continue
+			}
+			// already have a mapping for key. Update it.
+			val = add(unsafe.Pointer(b), dataOffset+bucketCnt*2*sys.PtrSize+i*uintptr(t.valuesize))
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(int64(h.count), h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if inserti == nil {
+		// all current buckets are full, allocate a new one.
+		newb := h.newoverflow(t, b)
+		inserti = &newb.tophash[0]
+		insertk = add(unsafe.Pointer(newb), dataOffset)
+		val = add(insertk, bucketCnt*2*sys.PtrSize)
+	}
+
+	// store new key/value at insert position
+	*((*stringStruct)(insertk)) = *key
+	*inserti = top
+	h.count++
+
+done:
+	if h.flags&hashWriting == 0 {
+		throw("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return val
+}
+
+func mapdelete_fast32(t *maptype, h *hmap, key uint32) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc(unsafe.Pointer(&t))
+		racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapdelete_fast32))
+	}
+	if h == nil || h.count == 0 {
+		return
+	}
+	if h.flags&hashWriting != 0 {
+		throw("concurrent map writes")
+	}
+
+	hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling alg.hash for consistency with mapdelete
+	h.flags |= hashWriting
+
+	bucket := hash & (uintptr(1)<<h.B - 1)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
+	top := uint8(hash >> (sys.PtrSize*8 - 8))
+	if top < minTopHash {
+		top += minTopHash
+	}
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				continue
+			}
+			k := (*uint32)(add(unsafe.Pointer(b), dataOffset+i*4))
+			if key != *k {
+				continue
+			}
+			typedmemclr(t.key, unsafe.Pointer(k))
+			v := unsafe.Pointer(uintptr(unsafe.Pointer(b)) + dataOffset + bucketCnt*4 + i*uintptr(t.valuesize))
+			typedmemclr(t.elem, v)
+			b.tophash[i] = empty
+			h.count--
+			goto done
+		}
+		b = b.overflow(t)
+		if b == nil {
+			goto done
+		}
+	}
+
+done:
+	if h.flags&hashWriting == 0 {
+		throw("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
+
+func mapdelete_fast64(t *maptype, h *hmap, key uint64) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc(unsafe.Pointer(&t))
+		racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapdelete_fast64))
+	}
+	if h == nil || h.count == 0 {
+		return
+	}
+	if h.flags&hashWriting != 0 {
+		throw("concurrent map writes")
+	}
+
+	hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling alg.hash for consistency with mapdelete
+	h.flags |= hashWriting
+
+	bucket := hash & (uintptr(1)<<h.B - 1)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
+	top := uint8(hash >> (sys.PtrSize*8 - 8))
+	if top < minTopHash {
+		top += minTopHash
+	}
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				continue
+			}
+			k := (*uint64)(add(unsafe.Pointer(b), dataOffset+i*8))
+			if key != *k {
+				continue
+			}
+			typedmemclr(t.key, unsafe.Pointer(k))
+			v := unsafe.Pointer(uintptr(unsafe.Pointer(b)) + dataOffset + bucketCnt*8 + i*uintptr(t.valuesize))
+			typedmemclr(t.elem, v)
+			b.tophash[i] = empty
+			h.count--
+			goto done
+		}
+		b = b.overflow(t)
+		if b == nil {
+			goto done
+		}
+	}
+
+done:
+	if h.flags&hashWriting == 0 {
+		throw("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
+
+func mapdelete_faststr(t *maptype, h *hmap, ky string) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc(unsafe.Pointer(&t))
+		racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapdelete_faststr))
+	}
+	if h == nil || h.count == 0 {
+		return
+	}
+	if h.flags&hashWriting != 0 {
+		throw("concurrent map writes")
+	}
+
+	key := stringStructOf(&ky)
+	hash := t.key.hashfn(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
+
+	// Set hashWriting after calling alg.hash for consistency with mapdelete
+	h.flags |= hashWriting
+
+	bucket := hash & (uintptr(1)<<h.B - 1)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
+	top := uint8(hash >> (sys.PtrSize*8 - 8))
+	if top < minTopHash {
+		top += minTopHash
+	}
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				continue
+			}
+			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+i*2*sys.PtrSize))
+			if k.len != key.len {
+				continue
+			}
+			if k.str != key.str && !memequal(k.str, key.str, uintptr(key.len)) {
+				continue
+			}
+			typedmemclr(t.key, unsafe.Pointer(k))
+			v := unsafe.Pointer(uintptr(unsafe.Pointer(b)) + dataOffset + bucketCnt*2*sys.PtrSize + i*uintptr(t.valuesize))
+			typedmemclr(t.elem, v)
+			b.tophash[i] = empty
+			h.count--
+			goto done
+		}
+		b = b.overflow(t)
+		if b == nil {
+			goto done
+		}
+	}
+
+done:
+	if h.flags&hashWriting == 0 {
+		throw("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
diff --git a/libgo/go/runtime/heapdump.go b/libgo/go/runtime/heapdump.go
index 0db53f5..166199b 100644
--- a/libgo/go/runtime/heapdump.go
+++ b/libgo/go/runtime/heapdump.go
@@ -413,7 +413,7 @@
 	dumpint(memstats.gc_sys)
 	dumpint(memstats.other_sys)
 	dumpint(memstats.next_gc)
-	dumpint(memstats.last_gc)
+	dumpint(memstats.last_gc_unix)
 	dumpint(memstats.pause_total_ns)
 	for i := 0; i < 256; i++ {
 		dumpint(memstats.pause_ns[i])
@@ -515,7 +515,7 @@
 	// Update stats so we can dump them.
 	// As a side effect, flushes all the MCaches so the MSpan.freelist
 	// lists contain all the free objects.
-	updatememstats(nil)
+	updatememstats()
 
 	// Set dump file.
 	dumpfd = fd
diff --git a/libgo/go/runtime/iface_test.go b/libgo/go/runtime/iface_test.go
index 3744a4f..d63ea79 100644
--- a/libgo/go/runtime/iface_test.go
+++ b/libgo/go/runtime/iface_test.go
@@ -29,6 +29,20 @@
 func (TL) Method1() {}
 func (TL) Method2() {}
 
+type T8 uint8
+type T16 uint16
+type T32 uint32
+type T64 uint64
+type Tstr string
+type Tslice []byte
+
+func (T8) Method1()     {}
+func (T16) Method1()    {}
+func (T32) Method1()    {}
+func (T64) Method1()    {}
+func (Tstr) Method1()   {}
+func (Tslice) Method1() {}
+
 var (
 	e  interface{}
 	e_ interface{}
@@ -269,3 +283,133 @@
 		t.Fatalf("want 0 allocs, got %v", n)
 	}
 }
+
+func TestZeroConvT2x(t *testing.T) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("does not work on gccgo without better escape analysis")
+	}
+
+	tests := []struct {
+		name string
+		fn   func()
+	}{
+		{name: "E8", fn: func() { e = eight8 }},  // any byte-sized value does not allocate
+		{name: "E16", fn: func() { e = zero16 }}, // zero values do not allocate
+		{name: "E32", fn: func() { e = zero32 }},
+		{name: "E64", fn: func() { e = zero64 }},
+		{name: "Estr", fn: func() { e = zerostr }},
+		{name: "Eslice", fn: func() { e = zeroslice }},
+		{name: "Econstflt", fn: func() { e = 99.0 }}, // constants do not allocate
+		{name: "Econststr", fn: func() { e = "change" }},
+		{name: "I8", fn: func() { i1 = eight8I }},
+		{name: "I16", fn: func() { i1 = zero16I }},
+		{name: "I32", fn: func() { i1 = zero32I }},
+		{name: "I64", fn: func() { i1 = zero64I }},
+		{name: "Istr", fn: func() { i1 = zerostrI }},
+		{name: "Islice", fn: func() { i1 = zerosliceI }},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			n := testing.AllocsPerRun(1000, test.fn)
+			if n != 0 {
+				t.Errorf("want zero allocs, got %v", n)
+			}
+		})
+	}
+}
+
+var (
+	eight8  uint8 = 8
+	eight8I T8    = 8
+
+	zero16  uint16 = 0
+	zero16I T16    = 0
+	one16   uint16 = 1
+
+	zero32  uint32 = 0
+	zero32I T32    = 0
+	one32   uint32 = 1
+
+	zero64  uint64 = 0
+	zero64I T64    = 0
+	one64   uint64 = 1
+
+	zerostr  string = ""
+	zerostrI Tstr   = ""
+	nzstr    string = "abc"
+
+	zeroslice  []byte = nil
+	zerosliceI Tslice = nil
+	nzslice    []byte = []byte("abc")
+
+	zerobig [512]byte
+	nzbig   [512]byte = [512]byte{511: 1}
+)
+
+func BenchmarkConvT2Ezero(b *testing.B) {
+	b.Run("zero", func(b *testing.B) {
+		b.Run("16", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = zero16
+			}
+		})
+		b.Run("32", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = zero32
+			}
+		})
+		b.Run("64", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = zero64
+			}
+		})
+		b.Run("str", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = zerostr
+			}
+		})
+		b.Run("slice", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = zeroslice
+			}
+		})
+		b.Run("big", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = zerobig
+			}
+		})
+	})
+	b.Run("nonzero", func(b *testing.B) {
+		b.Run("16", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = one16
+			}
+		})
+		b.Run("32", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = one32
+			}
+		})
+		b.Run("64", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = one64
+			}
+		})
+		b.Run("str", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = nzstr
+			}
+		})
+		b.Run("slice", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = nzslice
+			}
+		})
+		b.Run("big", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				e = nzbig
+			}
+		})
+	})
+}
diff --git a/libgo/go/runtime/internal/sys/intrinsics.go b/libgo/go/runtime/internal/sys/intrinsics.go
index 43acf34..2928280 100644
--- a/libgo/go/runtime/internal/sys/intrinsics.go
+++ b/libgo/go/runtime/internal/sys/intrinsics.go
@@ -14,22 +14,22 @@
 
 // Ctz64 counts trailing (low-order) zeroes,
 // and if all are zero, then 64.
-func Ctz64(x uint64) uint64 {
+func Ctz64(x uint64) int {
 	if x == 0 {
 		return 64
 	}
-	return uint64(builtinCtz64(x))
+	return int(builtinCtz64(x))
 }
 
 //go:nosplit
 
 // Ctz32 counts trailing (low-order) zeroes,
 // and if all are zero, then 32.
-func Ctz32(x uint32) uint32 {
+func Ctz32(x uint32) int {
 	if x == 0 {
 		return 32
 	}
-	return uint32(builtinCtz32(x))
+	return int(builtinCtz32(x))
 }
 
 //extern __builtin_bswap64
diff --git a/libgo/go/runtime/internal/sys/intrinsics_test.go b/libgo/go/runtime/internal/sys/intrinsics_test.go
index 1f2c8da..0444183 100644
--- a/libgo/go/runtime/internal/sys/intrinsics_test.go
+++ b/libgo/go/runtime/internal/sys/intrinsics_test.go
@@ -6,17 +6,17 @@
 )
 
 func TestCtz64(t *testing.T) {
-	for i := uint(0); i <= 64; i++ {
-		x := uint64(5) << i
-		if got := sys.Ctz64(x); got != uint64(i) {
+	for i := 0; i <= 64; i++ {
+		x := uint64(5) << uint(i)
+		if got := sys.Ctz64(x); got != i {
 			t.Errorf("Ctz64(%d)=%d, want %d", x, got, i)
 		}
 	}
 }
 func TestCtz32(t *testing.T) {
-	for i := uint(0); i <= 32; i++ {
-		x := uint32(5) << i
-		if got := sys.Ctz32(x); got != uint32(i) {
+	for i := 0; i <= 32; i++ {
+		x := uint32(5) << uint(i)
+		if got := sys.Ctz32(x); got != i {
 			t.Errorf("Ctz32(%d)=%d, want %d", x, got, i)
 		}
 	}
diff --git a/libgo/go/runtime/lfstack.go b/libgo/go/runtime/lfstack.go
index 2f2958c..4787c5b 100644
--- a/libgo/go/runtime/lfstack.go
+++ b/libgo/go/runtime/lfstack.go
@@ -3,10 +3,6 @@
 // license that can be found in the LICENSE file.
 
 // Lock-free stack.
-// Initialize head to 0, compare with 0 to test for emptiness.
-// The stack does not keep pointers to nodes,
-// so they can be garbage collected if there are no other pointers to nodes.
-// The following code runs only in non-preemptible contexts.
 
 package runtime
 
@@ -15,36 +11,47 @@
 	"unsafe"
 )
 
-// Temporary for C code to call:
-//go:linkname lfstackpush runtime.lfstackpush
-//go:linkname lfstackpop runtime.lfstackpop
+// lfstack is the head of a lock-free stack.
+//
+// The zero value of lfstack is an empty list.
+//
+// This stack is intrusive. Nodes must embed lfnode as the first field.
+//
+// The stack does not keep GC-visible pointers to nodes, so the caller
+// is responsible for ensuring the nodes are not garbage collected
+// (typically by allocating them from manually-managed memory).
+type lfstack uint64
 
-func lfstackpush(head *uint64, node *lfnode) {
+func (head *lfstack) push(node *lfnode) {
 	node.pushcnt++
 	new := lfstackPack(node, node.pushcnt)
 	if node1 := lfstackUnpack(new); node1 != node {
-		print("runtime: lfstackpush invalid packing: node=", node, " cnt=", hex(node.pushcnt), " packed=", hex(new), " -> node=", node1, "\n")
-		throw("lfstackpush")
+		print("runtime: lfstack.push invalid packing: node=", node, " cnt=", hex(node.pushcnt), " packed=", hex(new), " -> node=", node1, "\n")
+		throw("lfstack.push")
 	}
 	for {
-		old := atomic.Load64(head)
+		old := atomic.Load64((*uint64)(head))
 		node.next = old
-		if atomic.Cas64(head, old, new) {
+		if atomic.Cas64((*uint64)(head), old, new) {
 			break
 		}
 	}
 }
 
-func lfstackpop(head *uint64) unsafe.Pointer {
+func (head *lfstack) pop() unsafe.Pointer {
 	for {
-		old := atomic.Load64(head)
+		old := atomic.Load64((*uint64)(head))
 		if old == 0 {
 			return nil
 		}
 		node := lfstackUnpack(old)
 		next := atomic.Load64(&node.next)
-		if atomic.Cas64(head, old, next) {
+		if atomic.Cas64((*uint64)(head), old, next) {
 			return unsafe.Pointer(node)
 		}
 	}
 }
+
+func (head *lfstack) empty() bool {
+	return atomic.Load64((*uint64)(head)) == 0
+}
diff --git a/libgo/go/runtime/lock_futex.go b/libgo/go/runtime/lock_futex.go
index 9877bc3..7ddd378 100644
--- a/libgo/go/runtime/lock_futex.go
+++ b/libgo/go/runtime/lock_futex.go
@@ -50,6 +50,7 @@
 // affect mutex's state.
 
 // We use the uintptr mutex.key and note.key as a uint32.
+//go:nosplit
 func key32(p *uintptr) *uint32 {
 	return (*uint32)(unsafe.Pointer(p))
 }
@@ -152,9 +153,17 @@
 	if gp != gp.m.g0 {
 		throw("notesleep not on g0")
 	}
+	ns := int64(-1)
+	if *cgo_yield != nil {
+		// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
+		ns = 10e6
+	}
 	for atomic.Load(key32(&n.key)) == 0 {
 		gp.m.blocked = true
-		futexsleep(key32(&n.key), 0, -1)
+		futexsleep(key32(&n.key), 0, ns)
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
 		gp.m.blocked = false
 	}
 }
@@ -168,9 +177,16 @@
 	gp := getg()
 
 	if ns < 0 {
+		if *cgo_yield != nil {
+			// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
+			ns = 10e6
+		}
 		for atomic.Load(key32(&n.key)) == 0 {
 			gp.m.blocked = true
-			futexsleep(key32(&n.key), 0, -1)
+			futexsleep(key32(&n.key), 0, ns)
+			if *cgo_yield != nil {
+				asmcgocall(*cgo_yield, nil)
+			}
 			gp.m.blocked = false
 		}
 		return true
@@ -182,8 +198,14 @@
 
 	deadline := nanotime() + ns
 	for {
+		if *cgo_yield != nil && ns > 10e6 {
+			ns = 10e6
+		}
 		gp.m.blocked = true
 		futexsleep(key32(&n.key), 0, ns)
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
 		gp.m.blocked = false
 		if atomic.Load(key32(&n.key)) != 0 {
 			break
diff --git a/libgo/go/runtime/lock_sema.go b/libgo/go/runtime/lock_sema.go
index 57fee19..52a2376 100644
--- a/libgo/go/runtime/lock_sema.go
+++ b/libgo/go/runtime/lock_sema.go
@@ -175,7 +175,16 @@
 	}
 	// Queued. Sleep.
 	gp.m.blocked = true
-	semasleep(-1)
+	if *cgo_yield == nil {
+		semasleep(-1)
+	} else {
+		// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
+		const ns = 10e6
+		for atomic.Loaduintptr(&n.key) == 0 {
+			semasleep(ns)
+			asmcgocall(*cgo_yield, nil)
+		}
+	}
 	gp.m.blocked = false
 }
 
@@ -198,7 +207,15 @@
 	if ns < 0 {
 		// Queued. Sleep.
 		gp.m.blocked = true
-		semasleep(-1)
+		if *cgo_yield == nil {
+			semasleep(-1)
+		} else {
+			// Sleep in arbitrary-but-moderate intervals to poll libc interceptors.
+			const ns = 10e6
+			for semasleep(ns) < 0 {
+				asmcgocall(*cgo_yield, nil)
+			}
+		}
 		gp.m.blocked = false
 		return true
 	}
@@ -207,12 +224,18 @@
 	for {
 		// Registered. Sleep.
 		gp.m.blocked = true
+		if *cgo_yield != nil && ns > 10e6 {
+			ns = 10e6
+		}
 		if semasleep(ns) >= 0 {
 			gp.m.blocked = false
 			// Acquired semaphore, semawakeup unregistered us.
 			// Done.
 			return true
 		}
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
 		gp.m.blocked = false
 		// Interrupted or timed out. Still registered. Semaphore not acquired.
 		ns = deadline - nanotime()
diff --git a/libgo/go/runtime/malloc.go b/libgo/go/runtime/malloc.go
index 3912fc2..796cd8a 100644
--- a/libgo/go/runtime/malloc.go
+++ b/libgo/go/runtime/malloc.go
@@ -122,7 +122,7 @@
 
 	// Tiny allocator parameters, see "Tiny allocator" comment in malloc.go.
 	_TinySize      = 16
-	_TinySizeClass = 2
+	_TinySizeClass = int8(2)
 
 	_FixAllocChunk  = 16 << 10               // Chunk size for FixAlloc
 	_MaxMHeapList   = 1 << (20 - _PageShift) // Maximum page length for fixed-size list in MHeap.
@@ -159,7 +159,11 @@
 	_MHeapMap_TotalBits = (_64bit*sys.GoosWindows)*35 + (_64bit*(1-sys.GoosWindows)*(1-sys.GoosDarwin*sys.GoarchArm64))*39 + sys.GoosDarwin*sys.GoarchArm64*31 + (1-_64bit)*(32-(sys.GoarchMips+sys.GoarchMipsle))
 	_MHeapMap_Bits      = _MHeapMap_TotalBits - _PageShift
 
-	_MaxMem = uintptr(1<<_MHeapMap_TotalBits - 1)
+	// _MaxMem is the maximum heap arena size minus 1.
+	//
+	// On 32-bit, this is also the maximum heap pointer value,
+	// since the arena starts at address 0.
+	_MaxMem = 1<<_MHeapMap_TotalBits - 1
 
 	// Max number of threads to run garbage collection.
 	// 2, 3, and 4 are all plausible maximums depending
@@ -167,8 +171,6 @@
 	// collector scales well to 32 cpus.
 	_MaxGcproc = 32
 
-	_MaxArena32 = 1<<32 - 1
-
 	// minLegalPointer is the smallest possible legal pointer.
 	// This is the smallest possible architectural page size,
 	// since we assume that the first page is never mapped.
@@ -250,18 +252,21 @@
 		throw("bad system page size")
 	}
 
-	var p, bitmapSize, spansSize, pSize, limit uintptr
+	// The auxiliary regions start at p and are laid out in the
+	// following order: spans, bitmap, arena.
+	var p, pSize uintptr
 	var reserved bool
 
-	// limit = runtime.memlimit();
-	// See https://golang.org/issue/5049
-	// TODO(rsc): Fix after 1.1.
-	limit = 0
+	// The spans array holds one *mspan per _PageSize of arena.
+	var spansSize uintptr = (_MaxMem + 1) / _PageSize * sys.PtrSize
+	spansSize = round(spansSize, _PageSize)
+	// The bitmap holds 2 bits per word of arena.
+	var bitmapSize uintptr = (_MaxMem + 1) / (sys.PtrSize * 8 / 2)
+	bitmapSize = round(bitmapSize, _PageSize)
 
 	// Set up the allocation arena, a contiguous area of memory where
-	// allocated data will be found. The arena begins with a bitmap large
-	// enough to hold 2 bits per allocated word.
-	if sys.PtrSize == 8 && (limit == 0 || limit > 1<<30) {
+	// allocated data will be found.
+	if sys.PtrSize == 8 {
 		// On a 64-bit machine, allocate from a single contiguous reservation.
 		// 512 GB (MaxMem) should be big enough for now.
 		//
@@ -294,9 +299,7 @@
 		// On AIX, mmap adresses range start at 0x07000000_00000000 for 64 bits
 		// processes.
 		arenaSize := round(_MaxMem, _PageSize)
-		bitmapSize = arenaSize / (sys.PtrSize * 8 / 2)
-		spansSize = arenaSize / _PageSize * sys.PtrSize
-		spansSize = round(spansSize, _PageSize)
+		pSize = bitmapSize + spansSize + arenaSize + _PageSize
 		for i := 0; i <= 0x7f; i++ {
 			switch {
 			case GOARCH == "arm64" && GOOS == "darwin":
@@ -309,7 +312,6 @@
 			default:
 				p = uintptr(i)<<40 | uintptrMask&(0x00c0<<32)
 			}
-			pSize = bitmapSize + spansSize + arenaSize + _PageSize
 			p = uintptr(sysReserve(unsafe.Pointer(p), pSize, &reserved))
 			if p != 0 || GOOS == "aix" { // Useless to loop on AIX, as i is forced to 1
 				break
@@ -327,6 +329,15 @@
 		// When that gets used up, we'll start asking the kernel
 		// for any memory anywhere.
 
+		// We want to start the arena low, but if we're linked
+		// against C code, it's possible global constructors
+		// have called malloc and adjusted the process' brk.
+		// Query the brk so we can avoid trying to map the
+		// arena over it (which will cause the kernel to put
+		// the arena somewhere else, likely at a high
+		// address).
+		procBrk := sbrk0()
+
 		// If we fail to allocate, try again with a smaller arena.
 		// This is necessary on Android L where we share a process
 		// with ART, which reserves virtual memory aggressively.
@@ -340,15 +351,6 @@
 		}
 
 		for _, arenaSize := range &arenaSizes {
-			bitmapSize = (_MaxArena32 + 1) / (sys.PtrSize * 8 / 2)
-			spansSize = (_MaxArena32 + 1) / _PageSize * sys.PtrSize
-			if limit > 0 && arenaSize+bitmapSize+spansSize > limit {
-				bitmapSize = (limit / 9) &^ ((1 << _PageShift) - 1)
-				arenaSize = bitmapSize * 8
-				spansSize = arenaSize / _PageSize * sys.PtrSize
-			}
-			spansSize = round(spansSize, _PageSize)
-
 			// SysReserve treats the address we ask for, end, as a hint,
 			// not as an absolute requirement. If we ask for the end
 			// of the data segment but the operating system requires
@@ -360,6 +362,12 @@
 			// to a MB boundary.
 			p = round(getEnd()+(1<<18), 1<<20)
 			pSize = bitmapSize + spansSize + arenaSize + _PageSize
+			if p <= procBrk && procBrk < p+pSize {
+				// Move the start above the brk,
+				// leaving some room for future brk
+				// expansion.
+				p = round(procBrk+(1<<20), 1<<20)
+			}
 			p = uintptr(sysReserve(unsafe.Pointer(p), pSize, &reserved))
 			if p != 0 {
 				break
@@ -374,18 +382,22 @@
 	// so SysReserve can give us a PageSize-unaligned pointer.
 	// To overcome this we ask for PageSize more and round up the pointer.
 	p1 := round(p, _PageSize)
+	pSize -= p1 - p
 
 	spansStart := p1
-	mheap_.bitmap = p1 + spansSize + bitmapSize
+	p1 += spansSize
+	mheap_.bitmap = p1 + bitmapSize
+	p1 += bitmapSize
 	if sys.PtrSize == 4 {
 		// Set arena_start such that we can accept memory
 		// reservations located anywhere in the 4GB virtual space.
 		mheap_.arena_start = 0
 	} else {
-		mheap_.arena_start = p1 + (spansSize + bitmapSize)
+		mheap_.arena_start = p1
 	}
 	mheap_.arena_end = p + pSize
-	mheap_.arena_used = p1 + (spansSize + bitmapSize)
+	mheap_.arena_used = p1
+	mheap_.arena_alloc = p1
 	mheap_.arena_reserved = reserved
 
 	if mheap_.arena_start&(_PageSize-1) != 0 {
@@ -404,62 +416,78 @@
 // h.arena_start and h.arena_end. sysAlloc returns nil on failure.
 // There is no corresponding free function.
 func (h *mheap) sysAlloc(n uintptr) unsafe.Pointer {
-	if n > h.arena_end-h.arena_used {
-		// We are in 32-bit mode, maybe we didn't use all possible address space yet.
-		// Reserve some more space.
+	// strandLimit is the maximum number of bytes to strand from
+	// the current arena block. If we would need to strand more
+	// than this, we fall back to sysAlloc'ing just enough for
+	// this allocation.
+	const strandLimit = 16 << 20
+
+	if n > h.arena_end-h.arena_alloc {
+		// If we haven't grown the arena to _MaxMem yet, try
+		// to reserve some more address space.
 		p_size := round(n+_PageSize, 256<<20)
 		new_end := h.arena_end + p_size // Careful: can overflow
-		if h.arena_end <= new_end && new_end-h.arena_start-1 <= _MaxArena32 {
+		if h.arena_end <= new_end && new_end-h.arena_start-1 <= _MaxMem {
 			// TODO: It would be bad if part of the arena
 			// is reserved and part is not.
 			var reserved bool
 			p := uintptr(sysReserve(unsafe.Pointer(h.arena_end), p_size, &reserved))
 			if p == 0 {
-				return nil
+				// TODO: Try smaller reservation
+				// growths in case we're in a crowded
+				// 32-bit address space.
+				goto reservationFailed
 			}
 			// p can be just about anywhere in the address
 			// space, including before arena_end.
 			if p == h.arena_end {
+				// The new block is contiguous with
+				// the current block. Extend the
+				// current arena block.
 				h.arena_end = new_end
 				h.arena_reserved = reserved
-			} else if h.arena_end < p && p+p_size-h.arena_start-1 <= _MaxArena32 {
+			} else if h.arena_start <= p && p+p_size-h.arena_start-1 <= _MaxMem && h.arena_end-h.arena_alloc < strandLimit {
+				// We were able to reserve more memory
+				// within the arena space, but it's
+				// not contiguous with our previous
+				// reservation. It could be before or
+				// after our current arena_used.
+				//
 				// Keep everything page-aligned.
 				// Our pages are bigger than hardware pages.
 				h.arena_end = p + p_size
-				used := p + (-p & (_PageSize - 1))
-				h.mapBits(used)
-				h.mapSpans(used)
-				h.arena_used = used
+				p = round(p, _PageSize)
+				h.arena_alloc = p
 				h.arena_reserved = reserved
 			} else {
-				// We got a mapping, but it's not
-				// linear with our current arena, so
-				// we can't use it.
+				// We got a mapping, but either
 				//
-				// TODO: Make it possible to allocate
-				// from this. We can't decrease
-				// arena_used, but we could introduce
-				// a new variable for the current
-				// allocation position.
-
+				// 1) It's not in the arena, so we
+				// can't use it. (This should never
+				// happen on 32-bit.)
+				//
+				// 2) We would need to discard too
+				// much of our current arena block to
+				// use it.
+				//
 				// We haven't added this allocation to
 				// the stats, so subtract it from a
 				// fake stat (but avoid underflow).
+				//
+				// We'll fall back to a small sysAlloc.
 				stat := uint64(p_size)
 				sysFree(unsafe.Pointer(p), p_size, &stat)
 			}
 		}
 	}
 
-	if n <= h.arena_end-h.arena_used {
+	if n <= h.arena_end-h.arena_alloc {
 		// Keep taking from our reservation.
-		p := h.arena_used
+		p := h.arena_alloc
 		sysMap(unsafe.Pointer(p), n, h.arena_reserved, &memstats.heap_sys)
-		h.mapBits(p + n)
-		h.mapSpans(p + n)
-		h.arena_used = p + n
-		if raceenabled {
-			racemapshadow(unsafe.Pointer(p), n)
+		h.arena_alloc += n
+		if h.arena_alloc > h.arena_used {
+			h.setArenaUsed(h.arena_alloc, true)
 		}
 
 		if p&(_PageSize-1) != 0 {
@@ -468,8 +496,9 @@
 		return unsafe.Pointer(p)
 	}
 
+reservationFailed:
 	// If using 64-bit, our reservation is all we have.
-	if h.arena_end-h.arena_start > _MaxArena32 {
+	if sys.PtrSize != 4 {
 		return nil
 	}
 
@@ -481,28 +510,18 @@
 		return nil
 	}
 
-	if p < h.arena_start || p+p_size-h.arena_start > _MaxArena32 {
-		top := ^uintptr(0)
-		if top-h.arena_start-1 > _MaxArena32 {
-			top = h.arena_start + _MaxArena32 + 1
-		}
+	if p < h.arena_start || p+p_size-h.arena_start > _MaxMem {
+		// This shouldn't be possible because _MaxMem is the
+		// whole address space on 32-bit.
+		top := uint64(h.arena_start) + _MaxMem
 		print("runtime: memory allocated by OS (", hex(p), ") not in usable range [", hex(h.arena_start), ",", hex(top), ")\n")
 		sysFree(unsafe.Pointer(p), p_size, &memstats.heap_sys)
 		return nil
 	}
 
-	p_end := p + p_size
 	p += -p & (_PageSize - 1)
 	if p+n > h.arena_used {
-		h.mapBits(p + n)
-		h.mapSpans(p + n)
-		h.arena_used = p + n
-		if p_end > h.arena_end {
-			h.arena_end = p_end
-		}
-		if raceenabled {
-			racemapshadow(unsafe.Pointer(p), n)
-		}
+		h.setArenaUsed(p+n, true)
 	}
 
 	if p&(_PageSize-1) != 0 {
@@ -525,7 +544,7 @@
 			if freeidx%64 == 0 && freeidx != s.nelems {
 				return 0
 			}
-			s.allocCache >>= (theBit + 1)
+			s.allocCache >>= uint(theBit + 1)
 			s.freeindex = freeidx
 			v := gclinkptr(result*s.elemsize + s.base())
 			s.allocCount++
@@ -541,8 +560,8 @@
 // weight allocation. If it is a heavy weight allocation the caller must
 // determine whether a new GC cycle needs to be started or if the GC is active
 // whether this goroutine needs to assist the GC.
-func (c *mcache) nextFree(sizeclass uint8) (v gclinkptr, s *mspan, shouldhelpgc bool) {
-	s = c.alloc[sizeclass]
+func (c *mcache) nextFree(spc spanClass) (v gclinkptr, s *mspan, shouldhelpgc bool) {
+	s = c.alloc[spc]
 	shouldhelpgc = false
 	freeIndex := s.nextFreeIndex()
 	if freeIndex == s.nelems {
@@ -552,10 +571,10 @@
 			throw("s.allocCount != s.nelems && freeIndex == s.nelems")
 		}
 		systemstack(func() {
-			c.refill(int32(sizeclass))
+			c.refill(spc)
 		})
 		shouldhelpgc = true
-		s = c.alloc[sizeclass]
+		s = c.alloc[spc]
 
 		freeIndex = s.nextFreeIndex()
 	}
@@ -693,10 +712,10 @@
 				return x
 			}
 			// Allocate a new maxTinySize block.
-			span := c.alloc[tinySizeClass]
+			span := c.alloc[tinySpanClass]
 			v := nextFreeFast(span)
 			if v == 0 {
-				v, _, shouldhelpgc = c.nextFree(tinySizeClass)
+				v, _, shouldhelpgc = c.nextFree(tinySpanClass)
 			}
 			x = unsafe.Pointer(v)
 			(*[2]uint64)(x)[0] = 0
@@ -716,10 +735,11 @@
 				sizeclass = size_to_class128[(size-smallSizeMax+largeSizeDiv-1)/largeSizeDiv]
 			}
 			size = uintptr(class_to_size[sizeclass])
-			span := c.alloc[sizeclass]
+			spc := makeSpanClass(sizeclass, noscan)
+			span := c.alloc[spc]
 			v := nextFreeFast(span)
 			if v == 0 {
-				v, span, shouldhelpgc = c.nextFree(sizeclass)
+				v, span, shouldhelpgc = c.nextFree(spc)
 			}
 			x = unsafe.Pointer(v)
 			if needzero && span.needzero != 0 {
@@ -730,7 +750,7 @@
 		var s *mspan
 		shouldhelpgc = true
 		systemstack(func() {
-			s = largeAlloc(size, needzero)
+			s = largeAlloc(size, needzero, noscan)
 		})
 		s.freeindex = 1
 		s.allocCount = 1
@@ -739,9 +759,7 @@
 	}
 
 	var scanSize uintptr
-	if noscan {
-		heapBitsSetTypeNoScan(uintptr(x))
-	} else {
+	if !noscan {
 		heapBitsSetType(uintptr(x), size, dataSize, typ)
 		if dataSize > typ.size {
 			// Array allocation. If there are any
@@ -803,8 +821,10 @@
 		assistG.gcAssistBytes -= int64(size - dataSize)
 	}
 
-	if shouldhelpgc && gcShouldStart(false) {
-		gcStart(gcBackgroundMode, false)
+	if shouldhelpgc {
+		if t := (gcTrigger{kind: gcTriggerHeap}); t.test() {
+			gcStart(gcBackgroundMode, t)
+		}
 	}
 
 	if getg().preempt {
@@ -818,7 +838,7 @@
 	return x
 }
 
-func largeAlloc(size uintptr, needzero bool) *mspan {
+func largeAlloc(size uintptr, needzero bool, noscan bool) *mspan {
 	// print("largeAlloc size=", size, "\n")
 
 	if size+_PageSize < size {
@@ -834,7 +854,7 @@
 	// pays the debt down to npage pages.
 	deductSweepCredit(npages*_PageSize, npages)
 
-	s := mheap_.alloc(npages, 0, true, needzero)
+	s := mheap_.alloc(npages, makeSpanClass(0, noscan), true, needzero)
 	if s == nil {
 		throw("out of memory")
 	}
@@ -924,7 +944,7 @@
 		rate = 0x3fffffff
 	}
 	if rate != 0 {
-		return int32(int(fastrand()) % (2 * rate))
+		return int32(fastrand() % uint32(2*rate))
 	}
 	return 0
 }
diff --git a/libgo/go/runtime/malloc_test.go b/libgo/go/runtime/malloc_test.go
index bc5530c..0d43cf6 100644
--- a/libgo/go/runtime/malloc_test.go
+++ b/libgo/go/runtime/malloc_test.go
@@ -6,6 +6,8 @@
 
 import (
 	"flag"
+	"fmt"
+	"reflect"
 	. "runtime"
 	"testing"
 	"time"
@@ -22,24 +24,62 @@
 	st := new(MemStats)
 	ReadMemStats(st)
 
-	// Everything except HeapReleased, HeapIdle, and NumGC,
-	// because they indeed can be 0.
-	if st.Alloc == 0 || st.TotalAlloc == 0 || st.Sys == 0 || st.Lookups == 0 ||
-		st.Mallocs == 0 || st.Frees == 0 || st.HeapAlloc == 0 || st.HeapSys == 0 ||
-		st.HeapInuse == 0 || st.HeapObjects == 0 || st.StackInuse == 0 ||
-		st.StackSys == 0 || st.MSpanInuse == 0 || st.MSpanSys == 0 || st.MCacheInuse == 0 ||
-		st.MCacheSys == 0 || st.BuckHashSys == 0 || st.GCSys == 0 || st.OtherSys == 0 ||
-		st.NextGC == 0 || st.NumForcedGC == 0 {
-		t.Fatalf("Zero value: %+v", *st)
+	nz := func(x interface{}) error {
+		if x != reflect.Zero(reflect.TypeOf(x)).Interface() {
+			return nil
+		}
+		return fmt.Errorf("zero value")
+	}
+	le := func(thresh float64) func(interface{}) error {
+		return func(x interface{}) error {
+			if reflect.ValueOf(x).Convert(reflect.TypeOf(thresh)).Float() < thresh {
+				return nil
+			}
+			return fmt.Errorf("insanely high value (overflow?); want <= %v", thresh)
+		}
+	}
+	eq := func(x interface{}) func(interface{}) error {
+		return func(y interface{}) error {
+			if x == y {
+				return nil
+			}
+			return fmt.Errorf("want %v", x)
+		}
+	}
+	// Of the uint fields, HeapReleased, HeapIdle can be 0.
+	// PauseTotalNs can be 0 if timer resolution is poor.
+	//
+	// TODO: Test that GCCPUFraction is <= 0.99. This currently
+	// fails on windows/386. (Issue #19319)
+	fields := map[string][]func(interface{}) error{
+		"Alloc": {nz, le(1e10)}, "TotalAlloc": {nz, le(1e11)}, "Sys": {nz, le(1e10)},
+		"Lookups": {nz, le(1e10)}, "Mallocs": {nz, le(1e10)}, "Frees": {nz, le(1e10)},
+		"HeapAlloc": {nz, le(1e10)}, "HeapSys": {nz, le(1e10)}, "HeapIdle": {le(1e10)},
+		"HeapInuse": {nz, le(1e10)}, "HeapReleased": {le(1e10)}, "HeapObjects": {nz, le(1e10)},
+		"StackInuse": {nz, le(1e10)}, "StackSys": {nz, le(1e10)},
+		"MSpanInuse": {nz, le(1e10)}, "MSpanSys": {nz, le(1e10)},
+		"MCacheInuse": {nz, le(1e10)}, "MCacheSys": {nz, le(1e10)},
+		"BuckHashSys": {nz, le(1e10)}, "GCSys": {nz, le(1e10)}, "OtherSys": {nz, le(1e10)},
+		"NextGC": {nz, le(1e10)}, "LastGC": {nz},
+		"PauseTotalNs": {le(1e11)}, "PauseNs": nil, "PauseEnd": nil,
+		"NumGC": {nz, le(1e9)}, "NumForcedGC": {nz, le(1e9)},
+		"GCCPUFraction": nil, "EnableGC": {eq(true)}, "DebugGC": {eq(false)},
+		"BySize": nil,
 	}
 
-	if st.Alloc > 1e10 || st.TotalAlloc > 1e11 || st.Sys > 1e10 || st.Lookups > 1e10 ||
-		st.Mallocs > 1e10 || st.Frees > 1e10 || st.HeapAlloc > 1e10 || st.HeapSys > 1e10 ||
-		st.HeapIdle > 1e10 || st.HeapInuse > 1e10 || st.HeapObjects > 1e10 || st.StackInuse > 1e10 ||
-		st.StackSys > 1e10 || st.MSpanInuse > 1e10 || st.MSpanSys > 1e10 || st.MCacheInuse > 1e10 ||
-		st.MCacheSys > 1e10 || st.BuckHashSys > 1e10 || st.GCSys > 1e10 || st.OtherSys > 1e10 ||
-		st.NextGC > 1e10 || st.NumGC > 1e9 || st.NumForcedGC > 1e9 || st.PauseTotalNs > 1e11 {
-		t.Fatalf("Insanely high value (overflow?): %+v", *st)
+	rst := reflect.ValueOf(st).Elem()
+	for i := 0; i < rst.Type().NumField(); i++ {
+		name, val := rst.Type().Field(i).Name, rst.Field(i).Interface()
+		checks, ok := fields[name]
+		if !ok {
+			t.Errorf("unknown MemStats field %s", name)
+			continue
+		}
+		for _, check := range checks {
+			if err := check(val); err != nil {
+				t.Errorf("%s = %v: %s", name, val, err)
+			}
+		}
 	}
 	if st.Sys != st.HeapSys+st.StackSys+st.MSpanSys+st.MCacheSys+
 		st.BuckHashSys+st.GCSys+st.OtherSys {
diff --git a/libgo/go/runtime/map_test.go b/libgo/go/runtime/map_test.go
index 9b5b051..37c959f 100644
--- a/libgo/go/runtime/map_test.go
+++ b/libgo/go/runtime/map_test.go
@@ -10,6 +10,7 @@
 	"reflect"
 	"runtime"
 	"sort"
+	"strconv"
 	"strings"
 	"sync"
 	"testing"
@@ -594,6 +595,14 @@
 	}
 }
 
+// Test that making a map with a large or invalid hint
+// doesn't panic. (Issue 19926).
+func TestIgnoreBogusMapHint(t *testing.T) {
+	for _, hint := range []int64{-1, 1 << 62} {
+		_ = make(map[int]int, hint)
+	}
+}
+
 func benchmarkMapPop(b *testing.B, n int) {
 	m := map[int]int{}
 	for i := 0; i < b.N; i++ {
@@ -625,3 +634,86 @@
 		t.Fatalf("want 0 allocs, got %v", n)
 	}
 }
+
+func benchmarkMapAssignInt32(b *testing.B, n int) {
+	a := make(map[int32]int)
+	for i := 0; i < b.N; i++ {
+		a[int32(i&(n-1))] = i
+	}
+}
+
+func benchmarkMapDeleteInt32(b *testing.B, n int) {
+	a := make(map[int32]int)
+	for i := 0; i < n*b.N; i++ {
+		a[int32(i)] = i
+	}
+	b.ResetTimer()
+	for i := 0; i < n*b.N; i = i + n {
+		delete(a, int32(i))
+	}
+}
+
+func benchmarkMapAssignInt64(b *testing.B, n int) {
+	a := make(map[int64]int)
+	for i := 0; i < b.N; i++ {
+		a[int64(i&(n-1))] = i
+	}
+}
+
+func benchmarkMapDeleteInt64(b *testing.B, n int) {
+	a := make(map[int64]int)
+	for i := 0; i < n*b.N; i++ {
+		a[int64(i)] = i
+	}
+	b.ResetTimer()
+	for i := 0; i < n*b.N; i = i + n {
+		delete(a, int64(i))
+	}
+}
+
+func benchmarkMapAssignStr(b *testing.B, n int) {
+	k := make([]string, n)
+	for i := 0; i < len(k); i++ {
+		k[i] = strconv.Itoa(i)
+	}
+	b.ResetTimer()
+	a := make(map[string]int)
+	for i := 0; i < b.N; i++ {
+		a[k[i&(n-1)]] = i
+	}
+}
+
+func benchmarkMapDeleteStr(b *testing.B, n int) {
+	k := make([]string, n*b.N)
+	for i := 0; i < n*b.N; i++ {
+		k[i] = strconv.Itoa(i)
+	}
+	a := make(map[string]int)
+	for i := 0; i < n*b.N; i++ {
+		a[k[i]] = i
+	}
+	b.ResetTimer()
+	for i := 0; i < n*b.N; i = i + n {
+		delete(a, k[i])
+	}
+}
+
+func runWith(f func(*testing.B, int), v ...int) func(*testing.B) {
+	return func(b *testing.B) {
+		for _, n := range v {
+			b.Run(strconv.Itoa(n), func(b *testing.B) { f(b, n) })
+		}
+	}
+}
+
+func BenchmarkMapAssign(b *testing.B) {
+	b.Run("Int32", runWith(benchmarkMapAssignInt32, 1<<8, 1<<16))
+	b.Run("Int64", runWith(benchmarkMapAssignInt64, 1<<8, 1<<16))
+	b.Run("Str", runWith(benchmarkMapAssignStr, 1<<8, 1<<16))
+}
+
+func BenchmarkMapDelete(b *testing.B) {
+	b.Run("Int32", runWith(benchmarkMapDeleteInt32, 1, 2, 4))
+	b.Run("Int64", runWith(benchmarkMapDeleteInt64, 1, 2, 4))
+	b.Run("Str", runWith(benchmarkMapDeleteStr, 1, 2, 4))
+}
diff --git a/libgo/go/runtime/mapspeed_test.go b/libgo/go/runtime/mapspeed_test.go
index ac93119..aec0c51 100644
--- a/libgo/go/runtime/mapspeed_test.go
+++ b/libgo/go/runtime/mapspeed_test.go
@@ -5,6 +5,7 @@
 
 import (
 	"fmt"
+	"strconv"
 	"strings"
 	"testing"
 )
@@ -308,6 +309,20 @@
 	}
 }
 
+func BenchmarkMapPopulate(b *testing.B) {
+	for size := 1; size < 1000000; size *= 10 {
+		b.Run(strconv.Itoa(size), func(b *testing.B) {
+			b.ReportAllocs()
+			for i := 0; i < b.N; i++ {
+				m := make(map[int]bool)
+				for j := 0; j < size; j++ {
+					m[j] = true
+				}
+			}
+		})
+	}
+}
+
 type ComplexAlgKey struct {
 	a, b, c int64
 	_       int
diff --git a/libgo/go/runtime/mbarrier.go b/libgo/go/runtime/mbarrier.go
index 3a463c8..d54016f 100644
--- a/libgo/go/runtime/mbarrier.go
+++ b/libgo/go/runtime/mbarrier.go
@@ -156,6 +156,11 @@
 		// combine the read and the write. Checking inheap is
 		// insufficient since we need to track changes to
 		// roots outside the heap.
+		//
+		// Note: profbuf.go omits a barrier during signal handler
+		// profile logging; that's safe only because this deletion barrier exists.
+		// If we remove the deletion barrier, we'll have to work out
+		// a new way to handle the profile logging.
 		if slot1 := uintptr(unsafe.Pointer(slot)); slot1 >= minPhysPageSize {
 			if optr := *slot; optr != 0 {
 				shade(optr)
@@ -238,6 +243,7 @@
 }
 
 // typedmemmove copies a value of type t to dst from src.
+// Must be nosplit, see #16026.
 //go:nosplit
 func typedmemmove(typ *_type, dst, src unsafe.Pointer) {
 	if typ.kind&kindNoPointers == 0 {
diff --git a/libgo/go/runtime/mbitmap.go b/libgo/go/runtime/mbitmap.go
index a7ccc65..d1a5820 100644
--- a/libgo/go/runtime/mbitmap.go
+++ b/libgo/go/runtime/mbitmap.go
@@ -45,6 +45,11 @@
 // not checkmarked, and is the dead encoding.
 // These properties must be preserved when modifying the encoding.
 //
+// The bitmap for noscan spans is not maintained. Code must ensure
+// that an object is scannable before consulting its bitmap by
+// checking either the noscan bit in the span or by consulting its
+// type's information.
+//
 // Checkmarks
 //
 // In a concurrent garbage collector, one worries about failing to mark
@@ -134,13 +139,9 @@
 	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) - 1))
 }
 
-// mHeap_MapBits is called each time arena_used is extended.
-// It maps any additional bitmap memory needed for the new arena memory.
-// It must be called with the expected new value of arena_used,
-// *before* h.arena_used has been updated.
-// Waiting to update arena_used until after the memory has been mapped
-// avoids faults when other threads try access the bitmap immediately
-// after observing the change to arena_used.
+// mapBits maps any additional bitmap memory needed for the new arena memory.
+//
+// Don't call this directly. Call mheap.setArenaUsed.
 //
 //go:nowritebarrier
 func (h *mheap) mapBits(arena_used uintptr) {
@@ -186,10 +187,8 @@
 
 //go:nosplit
 func (s *mspan) allocBitsForIndex(allocBitIndex uintptr) markBits {
-	whichByte := allocBitIndex / 8
-	whichBit := allocBitIndex % 8
-	bytePtr := addb(s.allocBits, whichByte)
-	return markBits{bytePtr, uint8(1 << whichBit), allocBitIndex}
+	bytep, mask := s.allocBits.bitp(allocBitIndex)
+	return markBits{bytep, mask, allocBitIndex}
 }
 
 // refillaCache takes 8 bytes s.allocBits starting at whichByte
@@ -197,7 +196,7 @@
 // can be used. It then places these 8 bytes into the cached 64 bit
 // s.allocCache.
 func (s *mspan) refillAllocCache(whichByte uintptr) {
-	bytes := (*[8]uint8)(unsafe.Pointer(addb(s.allocBits, whichByte)))
+	bytes := (*[8]uint8)(unsafe.Pointer(s.allocBits.bytep(whichByte)))
 	aCache := uint64(0)
 	aCache |= uint64(bytes[0])
 	aCache |= uint64(bytes[1]) << (1 * 8)
@@ -248,7 +247,7 @@
 		return snelems
 	}
 
-	s.allocCache >>= (bitIndex + 1)
+	s.allocCache >>= uint(bitIndex + 1)
 	sfreeindex = result + 1
 
 	if sfreeindex%64 == 0 && sfreeindex != snelems {
@@ -269,10 +268,8 @@
 	if index < s.freeindex {
 		return false
 	}
-	whichByte := index / 8
-	whichBit := index % 8
-	byteVal := *addb(s.allocBits, whichByte)
-	return byteVal&uint8(1<<whichBit) == 0
+	bytep, mask := s.allocBits.bitp(index)
+	return *bytep&mask == 0
 }
 
 func (s *mspan) objIndex(p uintptr) uintptr {
@@ -294,14 +291,12 @@
 }
 
 func (s *mspan) markBitsForIndex(objIndex uintptr) markBits {
-	whichByte := objIndex / 8
-	bitMask := uint8(1 << (objIndex % 8)) // low 3 bits hold the bit index
-	bytePtr := addb(s.gcmarkBits, whichByte)
-	return markBits{bytePtr, bitMask, objIndex}
+	bytep, mask := s.gcmarkBits.bitp(objIndex)
+	return markBits{bytep, mask, objIndex}
 }
 
 func (s *mspan) markBitsForBase() markBits {
-	return markBits{s.gcmarkBits, uint8(1), 0}
+	return markBits{(*uint8)(s.gcmarkBits), uint8(1), 0}
 }
 
 // isMarked reports whether mark bit m is set.
@@ -332,11 +327,6 @@
 	atomic.And8(m.bytep, ^m.mask)
 }
 
-// clearMarkedNonAtomic clears the marked bit non-atomically.
-func (m markBits) clearMarkedNonAtomic() {
-	*m.bytep ^= m.mask
-}
-
 // markBitsForSpan returns the markBits for the span base address base.
 func markBitsForSpan(base uintptr) (mbits markBits) {
 	if base < mheap_.arena_start || base >= mheap_.arena_used {
@@ -404,7 +394,7 @@
 	// Consult the span table to find the block beginning.
 	s = mheap_.spans[idx]
 	if s == nil || p < s.base() || p >= s.limit || s.state != mSpanInUse {
-		if s == nil || s.state == _MSpanStack || forStack {
+		if s == nil || s.state == _MSpanManual || forStack {
 			// If s is nil, the virtual address has never been part of the heap.
 			// This pointer may be to some mmap'd region, so we allow it.
 			// Pointers into stacks are also ok, the runtime manages these explicitly.
@@ -434,6 +424,7 @@
 				print("runtime: found in object at *(", hex(refBase), "+", hex(refOff), ")\n")
 				gcDumpObject("object", refBase, refOff)
 			}
+			getg().m.traceback = 2
 			throw("found bad pointer in Go heap (incorrect use of unsafe or cgo?)")
 		}
 		return
@@ -524,16 +515,6 @@
 	return h.bits()&bitPointer != 0
 }
 
-// hasPointers reports whether the given object has any pointers.
-// It must be told how large the object at h is for efficiency.
-// h must describe the initial word of the object.
-func (h heapBits) hasPointers(size uintptr) bool {
-	if size == sys.PtrSize { // 1-word objects are always pointers
-		return true
-	}
-	return (*h.bitp>>h.shift)&bitScan != 0
-}
-
 // isCheckmarked reports whether the heap bits have the checkmarked bit set.
 // It must be told how large the object at h is, because the encoding of the
 // checkmark bit varies by size.
@@ -839,23 +820,23 @@
 	4, 5, 5, 6, 5, 6, 6, 7,
 	5, 6, 6, 7, 6, 7, 7, 8}
 
-// countFree runs through the mark bits in a span and counts the number of free objects
-// in the span.
+// countAlloc returns the number of objects allocated in span s by
+// scanning the allocation bitmap.
 // TODO:(rlh) Use popcount intrinsic.
-func (s *mspan) countFree() int {
+func (s *mspan) countAlloc() int {
 	count := 0
 	maxIndex := s.nelems / 8
 	for i := uintptr(0); i < maxIndex; i++ {
-		mrkBits := *addb(s.gcmarkBits, i)
+		mrkBits := *s.gcmarkBits.bytep(i)
 		count += int(oneBitCount[mrkBits])
 	}
 	if bitsInLastByte := s.nelems % 8; bitsInLastByte != 0 {
-		mrkBits := *addb(s.gcmarkBits, maxIndex)
+		mrkBits := *s.gcmarkBits.bytep(maxIndex)
 		mask := uint8((1 << bitsInLastByte) - 1)
 		bits := mrkBits & mask
 		count += int(oneBitCount[bits])
 	}
-	return int(s.nelems) - count
+	return count
 }
 
 // heapBitsSetType records that the new allocation [x, x+size)
@@ -1076,7 +1057,9 @@
 					endnb += endnb
 				}
 				// Truncate to a multiple of original ptrmask.
-				endnb = maxBits / nb * nb
+				// Because nb+nb <= maxBits, nb fits in a byte.
+				// Byte division is cheaper than uintptr division.
+				endnb = uintptr(maxBits/byte(nb)) * nb
 				pbits &= 1<<endnb - 1
 				b = pbits
 				nb = endnb
@@ -1354,13 +1337,6 @@
 	}
 }
 
-// heapBitsSetTypeNoScan marks x as noscan by setting the first word
-// of x in the heap bitmap to scalar/dead.
-func heapBitsSetTypeNoScan(x uintptr) {
-	h := heapBitsForAddr(uintptr(x))
-	*h.bitp &^= (bitPointer | bitScan) << h.shift
-}
-
 var debugPtrmask struct {
 	lock mutex
 	data *byte
diff --git a/libgo/go/runtime/mcache.go b/libgo/go/runtime/mcache.go
index 92dabef..71a2f22 100644
--- a/libgo/go/runtime/mcache.go
+++ b/libgo/go/runtime/mcache.go
@@ -33,7 +33,8 @@
 	local_tinyallocs uintptr // number of tiny allocs not counted in other stats
 
 	// The rest is not accessed on every malloc.
-	alloc [_NumSizeClasses]*mspan // spans to allocate from
+
+	alloc [numSpanClasses]*mspan // spans to allocate from, indexed by spanClass
 
 	// Local allocator stats, flushed during GC.
 	local_nlookup    uintptr                  // number of pointer lookups
@@ -70,7 +71,7 @@
 	lock(&mheap_.lock)
 	c := (*mcache)(mheap_.cachealloc.alloc())
 	unlock(&mheap_.lock)
-	for i := 0; i < _NumSizeClasses; i++ {
+	for i := range c.alloc {
 		c.alloc[i] = &emptymspan
 	}
 	c.next_sample = nextSample()
@@ -95,12 +96,12 @@
 
 // Gets a span that has a free object in it and assigns it
 // to be the cached span for the given sizeclass. Returns this span.
-func (c *mcache) refill(sizeclass int32) *mspan {
+func (c *mcache) refill(spc spanClass) *mspan {
 	_g_ := getg()
 
 	_g_.m.locks++
 	// Return the current cached span to the central lists.
-	s := c.alloc[sizeclass]
+	s := c.alloc[spc]
 
 	if uintptr(s.allocCount) != s.nelems {
 		throw("refill of span with free space remaining")
@@ -111,7 +112,7 @@
 	}
 
 	// Get a new cached span from the central lists.
-	s = mheap_.central[sizeclass].mcentral.cacheSpan()
+	s = mheap_.central[spc].mcentral.cacheSpan()
 	if s == nil {
 		throw("out of memory")
 	}
@@ -120,13 +121,13 @@
 		throw("span has no free space")
 	}
 
-	c.alloc[sizeclass] = s
+	c.alloc[spc] = s
 	_g_.m.locks--
 	return s
 }
 
 func (c *mcache) releaseAll() {
-	for i := 0; i < _NumSizeClasses; i++ {
+	for i := range c.alloc {
 		s := c.alloc[i]
 		if s != &emptymspan {
 			mheap_.central[i].mcentral.uncacheSpan(s)
diff --git a/libgo/go/runtime/mcentral.go b/libgo/go/runtime/mcentral.go
index ddcf81e..eaabcb9 100644
--- a/libgo/go/runtime/mcentral.go
+++ b/libgo/go/runtime/mcentral.go
@@ -19,14 +19,19 @@
 //go:notinheap
 type mcentral struct {
 	lock      mutex
-	sizeclass int32
+	spanclass spanClass
 	nonempty  mSpanList // list of spans with a free object, ie a nonempty free list
 	empty     mSpanList // list of spans with no free objects (or cached in an mcache)
+
+	// nmalloc is the cumulative count of objects allocated from
+	// this mcentral, assuming all spans in mcaches are
+	// fully-allocated. Written atomically, read under STW.
+	nmalloc uint64
 }
 
 // Initialize a single central free list.
-func (c *mcentral) init(sizeclass int32) {
-	c.sizeclass = sizeclass
+func (c *mcentral) init(spc spanClass) {
+	c.spanclass = spc
 	c.nonempty.init()
 	c.empty.init()
 }
@@ -34,10 +39,14 @@
 // Allocate a span to use in an MCache.
 func (c *mcentral) cacheSpan() *mspan {
 	// Deduct credit for this span allocation and sweep if necessary.
-	spanBytes := uintptr(class_to_allocnpages[c.sizeclass]) * _PageSize
+	spanBytes := uintptr(class_to_allocnpages[c.spanclass.sizeclass()]) * _PageSize
 	deductSweepCredit(spanBytes, 0)
 
 	lock(&c.lock)
+	traceDone := false
+	if trace.enabled {
+		traceGCSweepStart()
+	}
 	sg := mheap_.sweepgen
 retry:
 	var s *mspan
@@ -87,6 +96,10 @@
 		// all subsequent ones must also be either swept or in process of sweeping
 		break
 	}
+	if trace.enabled {
+		traceGCSweepDone()
+		traceDone = true
+	}
 	unlock(&c.lock)
 
 	// Replenish central list if empty.
@@ -101,15 +114,18 @@
 	// At this point s is a non-empty span, queued at the end of the empty list,
 	// c is unlocked.
 havespan:
+	if trace.enabled && !traceDone {
+		traceGCSweepDone()
+	}
 	cap := int32((s.npages << _PageShift) / s.elemsize)
 	n := cap - int32(s.allocCount)
 	if n == 0 || s.freeindex == s.nelems || uintptr(s.allocCount) == s.nelems {
 		throw("span has no free objects")
 	}
+	// Assume all objects from this span will be allocated in the
+	// mcache. If it gets uncached, we'll adjust this.
+	atomic.Xadd64(&c.nmalloc, int64(n))
 	usedBytes := uintptr(s.allocCount) * s.elemsize
-	if usedBytes > 0 {
-		reimburseSweepCredit(usedBytes)
-	}
 	atomic.Xadd64(&memstats.heap_live, int64(spanBytes)-int64(usedBytes))
 	if trace.enabled {
 		// heap_live changed.
@@ -150,6 +166,10 @@
 		// mCentral_CacheSpan conservatively counted
 		// unallocated slots in heap_live. Undo this.
 		atomic.Xadd64(&memstats.heap_live, -int64(n)*int64(s.elemsize))
+		// cacheSpan updated alloc assuming all objects on s
+		// were going to be allocated. Adjust for any that
+		// weren't.
+		atomic.Xadd64(&c.nmalloc, -int64(n))
 	}
 	unlock(&c.lock)
 }
@@ -205,11 +225,11 @@
 
 // grow allocates a new empty span from the heap and initializes it for c's size class.
 func (c *mcentral) grow() *mspan {
-	npages := uintptr(class_to_allocnpages[c.sizeclass])
-	size := uintptr(class_to_size[c.sizeclass])
+	npages := uintptr(class_to_allocnpages[c.spanclass.sizeclass()])
+	size := uintptr(class_to_size[c.spanclass.sizeclass()])
 	n := (npages << _PageShift) / size
 
-	s := mheap_.alloc(npages, c.sizeclass, false, true)
+	s := mheap_.alloc(npages, c.spanclass, false, true)
 	if s == nil {
 		return nil
 	}
diff --git a/libgo/go/runtime/mfinal.go b/libgo/go/runtime/mfinal.go
index 229ccb5..4353ee5 100644
--- a/libgo/go/runtime/mfinal.go
+++ b/libgo/go/runtime/mfinal.go
@@ -12,8 +12,12 @@
 	"unsafe"
 )
 
+// finblock is an array of finalizers to be executed. finblocks are
+// arranged in a linked list for the finalizer queue.
+//
 // finblock is allocated from non-GC'd memory, so any heap pointers
-// must be specially handled.
+// must be specially handled. GC currently assumes that the finalizer
+// queue does not grow during marking (but it can shrink).
 //
 //go:notinheap
 type finblock struct {
@@ -42,6 +46,16 @@
 }
 
 func queuefinalizer(p unsafe.Pointer, fn *funcval, ft *functype, ot *ptrtype) {
+	if gcphase != _GCoff {
+		// Currently we assume that the finalizer queue won't
+		// grow during marking so we don't have to rescan it
+		// during mark termination. If we ever need to lift
+		// this assumption, we can do it by adding the
+		// necessary barriers to queuefinalizer (which it may
+		// have automatically).
+		throw("queuefinalizer during GC")
+	}
+
 	lock(&finlock)
 	if finq == nil || finq.cnt == uint32(len(finq.fin)) {
 		if finc == nil {
@@ -399,7 +413,7 @@
 	}
 
 	n = s.elemsize
-	if s.sizeclass != 0 {
+	if s.spanclass.sizeclass() != 0 {
 		x = add(x, (uintptr(v)-uintptr(x))/n*n)
 	}
 	return
diff --git a/libgo/go/runtime/mfixalloc.go b/libgo/go/runtime/mfixalloc.go
index fe4b0fc..7496671 100644
--- a/libgo/go/runtime/mfixalloc.go
+++ b/libgo/go/runtime/mfixalloc.go
@@ -29,7 +29,7 @@
 	first  func(arg, p unsafe.Pointer) // called first time p is returned
 	arg    unsafe.Pointer
 	list   *mlink
-	chunk  unsafe.Pointer
+	chunk  uintptr // use uintptr instead of unsafe.Pointer to avoid write barriers
 	nchunk uint32
 	inuse  uintptr // in-use bytes now
 	stat   *uint64
@@ -54,7 +54,7 @@
 	f.first = first
 	f.arg = arg
 	f.list = nil
-	f.chunk = nil
+	f.chunk = 0
 	f.nchunk = 0
 	f.inuse = 0
 	f.stat = stat
@@ -77,15 +77,15 @@
 		return v
 	}
 	if uintptr(f.nchunk) < f.size {
-		f.chunk = persistentalloc(_FixAllocChunk, 0, f.stat)
+		f.chunk = uintptr(persistentalloc(_FixAllocChunk, 0, f.stat))
 		f.nchunk = _FixAllocChunk
 	}
 
-	v := f.chunk
+	v := unsafe.Pointer(f.chunk)
 	if f.first != nil {
 		f.first(f.arg, v)
 	}
-	f.chunk = add(f.chunk, f.size)
+	f.chunk = f.chunk + f.size
 	f.nchunk -= uint32(f.size)
 	f.inuse += f.size
 	return v
diff --git a/libgo/go/runtime/mgc.go b/libgo/go/runtime/mgc.go
index a4fc2be..31c4be8 100644
--- a/libgo/go/runtime/mgc.go
+++ b/libgo/go/runtime/mgc.go
@@ -178,17 +178,21 @@
 		throw("size of Workbuf is suboptimal")
 	}
 
+	// No sweep on the first cycle.
+	mheap_.sweepdone = 1
+
+	// Set a reasonable initial GC trigger.
+	memstats.triggerRatio = 7 / 8.0
+
+	// Fake a heap_marked value so it looks like a trigger at
+	// heapminimum is the appropriate growth from heap_marked.
+	// This will go into computing the initial GC goal.
+	memstats.heap_marked = uint64(float64(heapminimum) / (1 + memstats.triggerRatio))
+
+	// Set gcpercent from the environment. This will also compute
+	// and set the GC trigger and goal.
 	_ = setGCPercent(readgogc())
-	memstats.gc_trigger = heapminimum
-	// Compute the goal heap size based on the trigger:
-	//   trigger = marked * (1 + triggerRatio)
-	//   marked = trigger / (1 + triggerRatio)
-	//   goal = marked * (1 + GOGC/100)
-	//        = trigger / (1 + triggerRatio) * (1 + GOGC/100)
-	memstats.next_gc = uint64(float64(memstats.gc_trigger) / (1 + gcController.triggerRatio) * (1 + float64(gcpercent)/100))
-	if gcpercent < 0 {
-		memstats.next_gc = ^uint64(0)
-	}
+
 	work.startSema = 1
 	work.markDoneSema = 1
 }
@@ -224,12 +228,8 @@
 	}
 	gcpercent = in
 	heapminimum = defaultHeapMinimum * uint64(gcpercent) / 100
-	if gcController.triggerRatio > float64(gcpercent)/100 {
-		gcController.triggerRatio = float64(gcpercent) / 100
-	}
-	// This is either in gcinit or followed by a STW GC, both of
-	// which will reset other stats like memstats.gc_trigger and
-	// memstats.next_gc to appropriate values.
+	// Update pacing in response to gcpercent change.
+	gcSetTriggerRatio(memstats.triggerRatio)
 	unlock(&mheap_.lock)
 	return out
 }
@@ -239,7 +239,9 @@
 var gcphase uint32
 
 // The compiler knows about this variable.
-// If you change it, you must change the compiler too.
+// If you change it, you must change builtin/runtime.go, too.
+// If you change the first four bytes, you must also change the write
+// barrier insertion code.
 var writeBarrier struct {
 	enabled bool    // compiler emits a check of this before calling write barrier
 	pad     [3]byte // compiler uses 32-bit load for "enabled" field
@@ -329,10 +331,10 @@
 // utilization between assist and background marking to be 25% of
 // GOMAXPROCS. The high-level design of this algorithm is documented
 // at https://golang.org/s/go15gcpacing.
-var gcController = gcControllerState{
-	// Initial trigger ratio guess.
-	triggerRatio: 7 / 8.0,
-}
+//
+// All fields of gcController are used only during a single mark
+// cycle.
+var gcController gcControllerState
 
 type gcControllerState struct {
 	// scanWork is the total scan work performed this cycle. This
@@ -403,14 +405,6 @@
 	// beginning of each cycle.
 	fractionalUtilizationGoal float64
 
-	// triggerRatio is the heap growth ratio at which the garbage
-	// collection cycle should start. E.g., if this is 0.6, then
-	// GC should start when the live heap has reached 1.6 times
-	// the heap size marked by the previous cycle. This should be
-	// ≤ GOGC/100 so the trigger heap size is less than the goal
-	// heap size. This is updated at the end of of each cycle.
-	triggerRatio float64
-
 	_ [sys.CacheLineSize]byte
 
 	// fractionalMarkWorkersNeeded is the number of fractional
@@ -439,7 +433,7 @@
 	// first cycle) or may be much smaller (resulting in a large
 	// error response).
 	if memstats.gc_trigger <= heapminimum {
-		memstats.heap_marked = uint64(float64(memstats.gc_trigger) / (1 + c.triggerRatio))
+		memstats.heap_marked = uint64(float64(memstats.gc_trigger) / (1 + memstats.triggerRatio))
 	}
 
 	// Re-compute the heap goal for this cycle in case something
@@ -495,17 +489,12 @@
 
 // revise updates the assist ratio during the GC cycle to account for
 // improved estimates. This should be called either under STW or
-// whenever memstats.heap_scan or memstats.heap_live is updated (with
-// mheap_.lock held).
+// whenever memstats.heap_scan, memstats.heap_live, or
+// memstats.next_gc is updated (with mheap_.lock held).
 //
 // It should only be called when gcBlackenEnabled != 0 (because this
 // is when assists are enabled and the necessary statistics are
 // available).
-//
-// TODO: Consider removing the periodic controller update altogether.
-// Since we switched to allocating black, in theory we shouldn't have
-// to change the assist ratio. However, this is still a useful hook
-// that we've found many uses for when experimenting.
 func (c *gcControllerState) revise() {
 	// Compute the expected scan work remaining.
 	//
@@ -536,7 +525,7 @@
 	}
 
 	// Compute the heap distance remaining.
-	heapDistance := int64(memstats.next_gc) - int64(memstats.heap_live)
+	heapDistance := int64(memstats.next_gc) - int64(atomic.Load64(&memstats.heap_live))
 	if heapDistance <= 0 {
 		// This shouldn't happen, but if it does, avoid
 		// dividing by zero or setting the assist negative.
@@ -550,10 +539,15 @@
 	c.assistBytesPerWork = float64(heapDistance) / float64(scanWorkExpected)
 }
 
-// endCycle updates the GC controller state at the end of the
-// concurrent part of the GC cycle.
-func (c *gcControllerState) endCycle() {
-	h_t := c.triggerRatio // For debugging
+// endCycle computes the trigger ratio for the next cycle.
+func (c *gcControllerState) endCycle() float64 {
+	if work.userForced {
+		// Forced GC means this cycle didn't start at the
+		// trigger, so where it finished isn't good
+		// information about how to adjust the trigger.
+		// Just leave it where it is.
+		return memstats.triggerRatio
+	}
 
 	// Proportional response gain for the trigger controller. Must
 	// be in [0, 1]. Lower values smooth out transient effects but
@@ -582,25 +576,17 @@
 		utilization += float64(c.assistTime) / float64(assistDuration*int64(gomaxprocs))
 	}
 
-	triggerError := goalGrowthRatio - c.triggerRatio - utilization/gcGoalUtilization*(actualGrowthRatio-c.triggerRatio)
+	triggerError := goalGrowthRatio - memstats.triggerRatio - utilization/gcGoalUtilization*(actualGrowthRatio-memstats.triggerRatio)
 
 	// Finally, we adjust the trigger for next time by this error,
 	// damped by the proportional gain.
-	c.triggerRatio += triggerGain * triggerError
-	if c.triggerRatio < 0 {
-		// This can happen if the mutator is allocating very
-		// quickly or the GC is scanning very slowly.
-		c.triggerRatio = 0
-	} else if c.triggerRatio > goalGrowthRatio*0.95 {
-		// Ensure there's always a little margin so that the
-		// mutator assist ratio isn't infinity.
-		c.triggerRatio = goalGrowthRatio * 0.95
-	}
+	triggerRatio := memstats.triggerRatio + triggerGain*triggerError
 
 	if debug.gcpacertrace > 0 {
 		// Print controller state in terms of the design
 		// document.
 		H_m_prev := memstats.heap_marked
+		h_t := memstats.triggerRatio
 		H_T := memstats.gc_trigger
 		h_a := actualGrowthRatio
 		H_a := memstats.heap_live
@@ -620,6 +606,8 @@
 			" u_a/u_g=", u_a/u_g,
 			"\n")
 	}
+
+	return triggerRatio
 }
 
 // enlistWorker encourages another dedicated mark worker to start on
@@ -651,7 +639,7 @@
 	}
 	myID := gp.m.p.ptr().id
 	for tries := 0; tries < 5; tries++ {
-		id := int32(fastrand() % uint32(gomaxprocs-1))
+		id := int32(fastrandn(uint32(gomaxprocs - 1)))
 		if id >= myID {
 			id++
 		}
@@ -701,9 +689,6 @@
 		// This P is now dedicated to marking until the end of
 		// the concurrent mark phase.
 		_p_.gcMarkWorkerMode = gcMarkWorkerDedicatedMode
-		// TODO(austin): This P isn't going to run anything
-		// else for a while, so kick everything out of its run
-		// queue.
 	} else {
 		if !decIfPositive(&c.fractionalMarkWorkersNeeded) {
 			// No more workers are need right now.
@@ -761,6 +746,120 @@
 	return gp
 }
 
+// gcSetTriggerRatio sets the trigger ratio and updates everything
+// derived from it: the absolute trigger, the heap goal, mark pacing,
+// and sweep pacing.
+//
+// This can be called any time. If GC is the in the middle of a
+// concurrent phase, it will adjust the pacing of that phase.
+//
+// This depends on gcpercent, memstats.heap_marked, and
+// memstats.heap_live. These must be up to date.
+//
+// mheap_.lock must be held or the world must be stopped.
+func gcSetTriggerRatio(triggerRatio float64) {
+	// Set the trigger ratio, capped to reasonable bounds.
+	if triggerRatio < 0 {
+		// This can happen if the mutator is allocating very
+		// quickly or the GC is scanning very slowly.
+		triggerRatio = 0
+	} else if gcpercent >= 0 {
+		// Ensure there's always a little margin so that the
+		// mutator assist ratio isn't infinity.
+		maxTriggerRatio := 0.95 * float64(gcpercent) / 100
+		if triggerRatio > maxTriggerRatio {
+			triggerRatio = maxTriggerRatio
+		}
+	}
+	memstats.triggerRatio = triggerRatio
+
+	// Compute the absolute GC trigger from the trigger ratio.
+	//
+	// We trigger the next GC cycle when the allocated heap has
+	// grown by the trigger ratio over the marked heap size.
+	trigger := ^uint64(0)
+	if gcpercent >= 0 {
+		trigger = uint64(float64(memstats.heap_marked) * (1 + triggerRatio))
+		// Don't trigger below the minimum heap size.
+		minTrigger := heapminimum
+		if !gosweepdone() {
+			// Concurrent sweep happens in the heap growth
+			// from heap_live to gc_trigger, so ensure
+			// that concurrent sweep has some heap growth
+			// in which to perform sweeping before we
+			// start the next GC cycle.
+			sweepMin := atomic.Load64(&memstats.heap_live) + sweepMinHeapDistance*uint64(gcpercent)/100
+			if sweepMin > minTrigger {
+				minTrigger = sweepMin
+			}
+		}
+		if trigger < minTrigger {
+			trigger = minTrigger
+		}
+		if int64(trigger) < 0 {
+			print("runtime: next_gc=", memstats.next_gc, " heap_marked=", memstats.heap_marked, " heap_live=", memstats.heap_live, " initialHeapLive=", work.initialHeapLive, "triggerRatio=", triggerRatio, " minTrigger=", minTrigger, "\n")
+			throw("gc_trigger underflow")
+		}
+	}
+	memstats.gc_trigger = trigger
+
+	// Compute the next GC goal, which is when the allocated heap
+	// has grown by GOGC/100 over the heap marked by the last
+	// cycle.
+	goal := ^uint64(0)
+	if gcpercent >= 0 {
+		goal = memstats.heap_marked + memstats.heap_marked*uint64(gcpercent)/100
+		if goal < trigger {
+			// The trigger ratio is always less than GOGC/100, but
+			// other bounds on the trigger may have raised it.
+			// Push up the goal, too.
+			goal = trigger
+		}
+	}
+	memstats.next_gc = goal
+	if trace.enabled {
+		traceNextGC()
+	}
+
+	// Update mark pacing.
+	if gcphase != _GCoff {
+		gcController.revise()
+	}
+
+	// Update sweep pacing.
+	if gosweepdone() {
+		mheap_.sweepPagesPerByte = 0
+	} else {
+		// Concurrent sweep needs to sweep all of the in-use
+		// pages by the time the allocated heap reaches the GC
+		// trigger. Compute the ratio of in-use pages to sweep
+		// per byte allocated, accounting for the fact that
+		// some might already be swept.
+		heapLiveBasis := atomic.Load64(&memstats.heap_live)
+		heapDistance := int64(trigger) - int64(heapLiveBasis)
+		// Add a little margin so rounding errors and
+		// concurrent sweep are less likely to leave pages
+		// unswept when GC starts.
+		heapDistance -= 1024 * 1024
+		if heapDistance < _PageSize {
+			// Avoid setting the sweep ratio extremely high
+			heapDistance = _PageSize
+		}
+		pagesSwept := atomic.Load64(&mheap_.pagesSwept)
+		sweepDistancePages := int64(mheap_.pagesInUse) - int64(pagesSwept)
+		if sweepDistancePages <= 0 {
+			mheap_.sweepPagesPerByte = 0
+		} else {
+			mheap_.sweepPagesPerByte = float64(sweepDistancePages) / float64(heapDistance)
+			mheap_.sweepHeapLiveBasis = heapLiveBasis
+			// Write pagesSweptBasis last, since this
+			// signals concurrent sweeps to recompute
+			// their debt.
+			atomic.Store64(&mheap_.pagesSweptBasis, pagesSwept)
+		}
+	}
+}
+
 // gcGoalUtilization is the goal CPU utilization for background
 // marking as a fraction of GOMAXPROCS.
 const gcGoalUtilization = 0.25
@@ -783,10 +882,23 @@
 const gcOverAssistWork = 64 << 10
 
 var work struct {
-	full  uint64                   // lock-free list of full blocks workbuf
-	empty uint64                   // lock-free list of empty blocks workbuf
+	full  lfstack                  // lock-free list of full blocks workbuf
+	empty lfstack                  // lock-free list of empty blocks workbuf
 	pad0  [sys.CacheLineSize]uint8 // prevents false-sharing between full/empty and nproc/nwait
 
+	wbufSpans struct {
+		lock mutex
+		// free is a list of spans dedicated to workbufs, but
+		// that don't currently contain any workbufs.
+		free mSpanList
+		// busy is a list of all spans containing workbufs on
+		// one of the workbuf lists.
+		busy mSpanList
+	}
+
+	// Restore 64-bit alignment on 32-bit.
+	_ uint32
+
 	// bytesMarked is the number of bytes marked this cycle. This
 	// includes bytes blackened in scanned objects, noscan objects
 	// that go straight to black, and permagrey objects scanned by
@@ -816,15 +928,13 @@
 	// should pass gcDrainBlock to gcDrain to block in the
 	// getfull() barrier. Otherwise, they should pass gcDrainNoBlock.
 	//
-	// TODO: This is a temporary fallback to support
-	// debug.gcrescanstacks > 0 and to work around some known
-	// races. Remove this when we remove the debug option and fix
-	// the races.
+	// TODO: This is a temporary fallback to work around races
+	// that cause early mark termination.
 	helperDrainBlock bool
 
 	// Number of roots of various root types. Set by gcMarkRootPrepare.
-	nFlushCacheRoots                                  int
-	nDataRoots, nSpanRoots, nStackRoots, nRescanRoots int
+	nFlushCacheRoots                    int
+	nDataRoots, nSpanRoots, nStackRoots int
 
 	// markrootDone indicates that roots have been marked at least
 	// once during the current GC cycle. This is checked by root
@@ -860,6 +970,10 @@
 	// mode is the concurrency mode of the current GC cycle.
 	mode gcMode
 
+	// userForced indicates the current GC cycle was forced by an
+	// explicit user call.
+	userForced bool
+
 	// totaltime is the CPU nanoseconds spent in GC since the
 	// program started if debug.gctrace > 0.
 	totaltime int64
@@ -876,14 +990,19 @@
 		head, tail guintptr
 	}
 
-	// rescan is a list of G's that need to be rescanned during
-	// mark termination. A G adds itself to this list when it
-	// first invalidates its stack scan.
-	rescan struct {
+	// sweepWaiters is a list of blocked goroutines to wake when
+	// we transition from mark termination to sweep.
+	sweepWaiters struct {
 		lock mutex
-		list []guintptr
+		head guintptr
 	}
 
+	// cycles is the number of completed GC cycles, where a GC
+	// cycle is sweep termination, mark, mark termination, and
+	// sweep. This differs from memstats.numgc, which is
+	// incremented at mark termination.
+	cycles uint32
+
 	// Timing/utilization stats for this cycle.
 	stwprocs, maxprocs                 int32
 	tSweepTerm, tMark, tMarkTerm, tEnd int64 // nanotime() of phase start
@@ -899,7 +1018,94 @@
 // garbage collection is complete. It may also block the entire
 // program.
 func GC() {
-	gcStart(gcForceBlockMode, false)
+	// We consider a cycle to be: sweep termination, mark, mark
+	// termination, and sweep. This function shouldn't return
+	// until a full cycle has been completed, from beginning to
+	// end. Hence, we always want to finish up the current cycle
+	// and start a new one. That means:
+	//
+	// 1. In sweep termination, mark, or mark termination of cycle
+	// N, wait until mark termination N completes and transitions
+	// to sweep N.
+	//
+	// 2. In sweep N, help with sweep N.
+	//
+	// At this point we can begin a full cycle N+1.
+	//
+	// 3. Trigger cycle N+1 by starting sweep termination N+1.
+	//
+	// 4. Wait for mark termination N+1 to complete.
+	//
+	// 5. Help with sweep N+1 until it's done.
+	//
+	// This all has to be written to deal with the fact that the
+	// GC may move ahead on its own. For example, when we block
+	// until mark termination N, we may wake up in cycle N+2.
+
+	gp := getg()
+
+	// Prevent the GC phase or cycle count from changing.
+	lock(&work.sweepWaiters.lock)
+	n := atomic.Load(&work.cycles)
+	if gcphase == _GCmark {
+		// Wait until sweep termination, mark, and mark
+		// termination of cycle N complete.
+		gp.schedlink = work.sweepWaiters.head
+		work.sweepWaiters.head.set(gp)
+		goparkunlock(&work.sweepWaiters.lock, "wait for GC cycle", traceEvGoBlock, 1)
+	} else {
+		// We're in sweep N already.
+		unlock(&work.sweepWaiters.lock)
+	}
+
+	// We're now in sweep N or later. Trigger GC cycle N+1, which
+	// will first finish sweep N if necessary and then enter sweep
+	// termination N+1.
+	gcStart(gcBackgroundMode, gcTrigger{kind: gcTriggerCycle, n: n + 1})
+
+	// Wait for mark termination N+1 to complete.
+	lock(&work.sweepWaiters.lock)
+	if gcphase == _GCmark && atomic.Load(&work.cycles) == n+1 {
+		gp.schedlink = work.sweepWaiters.head
+		work.sweepWaiters.head.set(gp)
+		goparkunlock(&work.sweepWaiters.lock, "wait for GC cycle", traceEvGoBlock, 1)
+	} else {
+		unlock(&work.sweepWaiters.lock)
+	}
+
+	// Finish sweep N+1 before returning. We do this both to
+	// complete the cycle and because runtime.GC() is often used
+	// as part of tests and benchmarks to get the system into a
+	// relatively stable and isolated state.
+	for atomic.Load(&work.cycles) == n+1 && gosweepone() != ^uintptr(0) {
+		sweep.nbgsweep++
+		Gosched()
+	}
+
+	// Callers may assume that the heap profile reflects the
+	// just-completed cycle when this returns (historically this
+	// happened because this was a STW GC), but right now the
+	// profile still reflects mark termination N, not N+1.
+	//
+	// As soon as all of the sweep frees from cycle N+1 are done,
+	// we can go ahead and publish the heap profile.
+	//
+	// First, wait for sweeping to finish. (We know there are no
+	// more spans on the sweep queue, but we may be concurrently
+	// sweeping spans, so we have to wait.)
+	for atomic.Load(&work.cycles) == n+1 && atomic.Load(&mheap_.sweepers) != 0 {
+		Gosched()
+	}
+
+	// Now we're really done with sweeping, so we can publish the
+	// stable heap profile. Only do this if we haven't already hit
+	// another mark termination.
+	mp := acquirem()
+	cycle := atomic.Load(&work.cycles)
+	if cycle == n+1 || (gcphase == _GCmark && cycle == n+2) {
+		mProf_PostSweep()
+	}
+	releasem(mp)
 }
 
 // gcMode indicates how concurrent a GC cycle should be.
@@ -911,24 +1117,75 @@
 	gcForceBlockMode               // stop-the-world GC now and STW sweep (forced by user)
 )
 
-// gcShouldStart returns true if the exit condition for the _GCoff
-// phase has been met. The exit condition should be tested when
-// allocating.
-//
-// If forceTrigger is true, it ignores the current heap size, but
-// checks all other conditions. In general this should be false.
-func gcShouldStart(forceTrigger bool) bool {
-	return gcphase == _GCoff && (forceTrigger || memstats.heap_live >= memstats.gc_trigger) && memstats.enablegc && panicking == 0 && gcpercent >= 0
+// A gcTrigger is a predicate for starting a GC cycle. Specifically,
+// it is an exit condition for the _GCoff phase.
+type gcTrigger struct {
+	kind gcTriggerKind
+	now  int64  // gcTriggerTime: current time
+	n    uint32 // gcTriggerCycle: cycle number to start
 }
 
-// gcStart transitions the GC from _GCoff to _GCmark (if mode ==
-// gcBackgroundMode) or _GCmarktermination (if mode !=
-// gcBackgroundMode) by performing sweep termination and GC
-// initialization.
+type gcTriggerKind int
+
+const (
+	// gcTriggerAlways indicates that a cycle should be started
+	// unconditionally, even if GOGC is off or we're in a cycle
+	// right now. This cannot be consolidated with other cycles.
+	gcTriggerAlways gcTriggerKind = iota
+
+	// gcTriggerHeap indicates that a cycle should be started when
+	// the heap size reaches the trigger heap size computed by the
+	// controller.
+	gcTriggerHeap
+
+	// gcTriggerTime indicates that a cycle should be started when
+	// it's been more than forcegcperiod nanoseconds since the
+	// previous GC cycle.
+	gcTriggerTime
+
+	// gcTriggerCycle indicates that a cycle should be started if
+	// we have not yet started cycle number gcTrigger.n (relative
+	// to work.cycles).
+	gcTriggerCycle
+)
+
+// test returns true if the trigger condition is satisfied, meaning
+// that the exit condition for the _GCoff phase has been met. The exit
+// condition should be tested when allocating.
+func (t gcTrigger) test() bool {
+	if !memstats.enablegc || panicking != 0 {
+		return false
+	}
+	if t.kind == gcTriggerAlways {
+		return true
+	}
+	if gcphase != _GCoff || gcpercent < 0 {
+		return false
+	}
+	switch t.kind {
+	case gcTriggerHeap:
+		// Non-atomic access to heap_live for performance. If
+		// we are going to trigger on this, this thread just
+		// atomically wrote heap_live anyway and we'll see our
+		// own write.
+		return memstats.heap_live >= memstats.gc_trigger
+	case gcTriggerTime:
+		lastgc := int64(atomic.Load64(&memstats.last_gc_nanotime))
+		return lastgc != 0 && t.now-lastgc > forcegcperiod
+	case gcTriggerCycle:
+		// t.n > work.cycles, but accounting for wraparound.
+		return int32(t.n-work.cycles) > 0
+	}
+	return true
+}
+
+// gcStart transitions the GC from _GCoff to _GCmark (if
+// !mode.stwMark) or _GCmarktermination (if mode.stwMark) by
+// performing sweep termination and GC initialization.
 //
 // This may return without performing this transition in some cases,
 // such as when called on a system stack or with locks held.
-func gcStart(mode gcMode, forceTrigger bool) {
+func gcStart(mode gcMode, trigger gcTrigger) {
 	// Since this is called from malloc and malloc is called in
 	// the guts of a number of libraries that might be holding
 	// locks, don't attempt to start GC in non-preemptible or
@@ -951,29 +1208,21 @@
 	//
 	// We check the transition condition continuously here in case
 	// this G gets delayed in to the next GC cycle.
-	for (mode != gcBackgroundMode || gcShouldStart(forceTrigger)) && gosweepone() != ^uintptr(0) {
+	for trigger.test() && gosweepone() != ^uintptr(0) {
 		sweep.nbgsweep++
 	}
 
 	// Perform GC initialization and the sweep termination
 	// transition.
-	//
-	// If this is a forced GC, don't acquire the transition lock
-	// or re-check the transition condition because we
-	// specifically *don't* want to share the transition with
-	// another thread.
-	useStartSema := mode == gcBackgroundMode
-	if useStartSema {
-		semacquire(&work.startSema, 0)
-		// Re-check transition condition under transition lock.
-		if !gcShouldStart(forceTrigger) {
-			semrelease(&work.startSema)
-			return
-		}
+	semacquire(&work.startSema)
+	// Re-check transition condition under transition lock.
+	if !trigger.test() {
+		semrelease(&work.startSema)
+		return
 	}
 
 	// For stats, check if this GC was forced by the user.
-	forced := mode != gcBackgroundMode
+	work.userForced = trigger.kind == gcTriggerAlways || trigger.kind == gcTriggerCycle
 
 	// In gcstoptheworld debug mode, upgrade the mode accordingly.
 	// We do this after re-checking the transition condition so
@@ -988,7 +1237,7 @@
 	}
 
 	// Ok, we're doing it!  Stop everybody else
-	semacquire(&worldsema, 0)
+	semacquire(&worldsema)
 
 	if trace.enabled {
 		traceGCStart()
@@ -1000,13 +1249,13 @@
 
 	gcResetMarkState()
 
-	now := nanotime()
 	work.stwprocs, work.maxprocs = gcprocs(), gomaxprocs
-	work.tSweepTerm = now
-	work.heap0 = memstats.heap_live
+	work.heap0 = atomic.Load64(&memstats.heap_live)
 	work.pauseNS = 0
 	work.mode = mode
 
+	now := nanotime()
+	work.tSweepTerm = now
 	work.pauseStart = now
 	systemstack(stopTheWorldWithSema)
 	// Finish sweep before we start concurrent scan.
@@ -1017,6 +1266,7 @@
 	// reclaimed until the next GC cycle.
 	clearpools()
 
+	work.cycles++
 	if mode == gcBackgroundMode { // Do as much work concurrently as possible
 		gcController.startCycle()
 		work.heapGoal = memstats.next_gc
@@ -1029,18 +1279,7 @@
 		// the time we start the world and begin
 		// scanning.
 		//
-		// It's necessary to enable write barriers
-		// during the scan phase for several reasons:
-		//
-		// They must be enabled for writes to higher
-		// stack frames before we scan stacks and
-		// install stack barriers because this is how
-		// we track writes to inactive stack frames.
-		// (Alternatively, we could not install stack
-		// barriers over frame boundaries with
-		// up-pointers).
-		//
-		// They must be enabled before assists are
+		// Write barriers must be enabled before assists are
 		// enabled because they must be enabled before
 		// any non-leaf heap objects are marked. Since
 		// allocations are blocked until assists can
@@ -1079,17 +1318,11 @@
 		work.tMark, work.tMarkTerm = t, t
 		work.heapGoal = work.heap0
 
-		if forced {
-			memstats.numforcedgc++
-		}
-
 		// Perform mark termination. This will restart the world.
-		gcMarkTermination()
+		gcMarkTermination(memstats.triggerRatio)
 	}
 
-	if useStartSema {
-		semrelease(&work.startSema)
-	}
+	semrelease(&work.startSema)
 }
 
 // gcMarkDone transitions the GC from mark 1 to mark 2 and from mark 2
@@ -1109,7 +1342,7 @@
 // by mark termination.
 func gcMarkDone() {
 top:
-	semacquire(&work.markDoneSema, 0)
+	semacquire(&work.markDoneSema)
 
 	// Re-check transition condition under transition lock.
 	if !(gcphase == _GCmark && work.nwait == work.nproc && !gcMarkWorkAvailable(nil)) {
@@ -1204,14 +1437,14 @@
 
 		// endCycle depends on all gcWork cache stats being
 		// flushed. This is ensured by mark 2.
-		gcController.endCycle()
+		nextTriggerRatio := gcController.endCycle()
 
 		// Perform mark termination. This will restart the world.
-		gcMarkTermination()
+		gcMarkTermination(nextTriggerRatio)
 	}
 }
 
-func gcMarkTermination() {
+func gcMarkTermination(nextTriggerRatio float64) {
 	// World is stopped.
 	// Start marktermination which includes enabling the write barrier.
 	atomic.Store(&gcBlackenEnabled, 0)
@@ -1293,11 +1526,17 @@
 		throw("gc done but gcphase != _GCoff")
 	}
 
+	// Update GC trigger and pacing for the next cycle.
+	gcSetTriggerRatio(nextTriggerRatio)
+
 	// Update timing memstats
-	now, unixNow := nanotime(), unixnanotime()
+	now := nanotime()
+	sec, nsec, _ := time_now()
+	unixNow := sec*1e9 + int64(nsec)
 	work.pauseNS += now - work.pauseStart
 	work.tEnd = now
-	atomic.Store64(&memstats.last_gc, uint64(unixNow)) // must be Unix time to make sense to user
+	atomic.Store64(&memstats.last_gc_unix, uint64(unixNow)) // must be Unix time to make sense to user
+	atomic.Store64(&memstats.last_gc_nanotime, uint64(now)) // monotonic time for us
 	memstats.pause_ns[memstats.numgc%uint32(len(memstats.pause_ns))] = uint64(work.pauseNS)
 	memstats.pause_end[memstats.numgc%uint32(len(memstats.pause_end))] = uint64(unixNow)
 	memstats.pause_total_ns += uint64(work.pauseNS)
@@ -1315,25 +1554,36 @@
 	totalCpu := sched.totaltime + (now-sched.procresizetime)*int64(gomaxprocs)
 	memstats.gc_cpu_fraction = float64(work.totaltime) / float64(totalCpu)
 
-	memstats.numgc++
-
 	// Reset sweep state.
 	sweep.nbgsweep = 0
 	sweep.npausesweep = 0
 
+	if work.userForced {
+		memstats.numforcedgc++
+	}
+
+	// Bump GC cycle count and wake goroutines waiting on sweep.
+	lock(&work.sweepWaiters.lock)
+	memstats.numgc++
+	injectglist(work.sweepWaiters.head.ptr())
+	work.sweepWaiters.head = 0
+	unlock(&work.sweepWaiters.lock)
+
+	// Finish the current heap profiling cycle and start a new
+	// heap profiling cycle. We do this before starting the world
+	// so events don't leak into the wrong cycle.
+	mProf_NextCycle()
+
 	systemstack(startTheWorldWithSema)
 
-	// Update heap profile stats if gcSweep didn't do it. This is
-	// relatively expensive, so we don't want to do it while the
-	// world is stopped, but it needs to happen ASAP after
-	// starting the world to prevent too many allocations from the
-	// next cycle leaking in. It must happen before releasing
-	// worldsema since there are applications that do a
-	// runtime.GC() to update the heap profile and then
-	// immediately collect the profile.
-	if _ConcurrentSweep && work.mode != gcForceBlockMode {
-		mProf_GC()
-	}
+	// Flush the heap profile so we can start a new cycle next GC.
+	// This is relatively expensive, so we don't do it with the
+	// world stopped.
+	mProf_Flush()
+
+	// Prepare workbufs for freeing by the sweeper. We do this
+	// asynchronously because it can take non-trivial time.
+	prepareFreeWorkbufs()
 
 	// Print gctrace before dropping worldsema. As soon as we drop
 	// worldsema another cycle could start and smash the stats
@@ -1368,7 +1618,7 @@
 			work.heap0>>20, "->", work.heap1>>20, "->", work.heap2>>20, " MB, ",
 			work.heapGoal>>20, " MB goal, ",
 			work.maxprocs, " P")
-		if work.mode != gcBackgroundMode {
+		if work.userForced {
 			print(" (forced)")
 		}
 		print("\n")
@@ -1521,6 +1771,25 @@
 			default:
 				throw("gcBgMarkWorker: unexpected gcMarkWorkerMode")
 			case gcMarkWorkerDedicatedMode:
+				gcDrain(&_p_.gcw, gcDrainUntilPreempt|gcDrainFlushBgCredit)
+				if gp.preempt {
+					// We were preempted. This is
+					// a useful signal to kick
+					// everything out of the run
+					// queue so it can run
+					// somewhere else.
+					lock(&sched.lock)
+					for {
+						gp, _ := runqget(_p_)
+						if gp == nil {
+							break
+						}
+						globrunqput(gp)
+					}
+					unlock(&sched.lock)
+				}
+				// Go back to draining, this time
+				// without preemption.
 				gcDrain(&_p_.gcw, gcDrainNoBlock|gcDrainFlushBgCredit)
 			case gcMarkWorkerFractionalMode:
 				gcDrain(&_p_.gcw, gcDrainUntilPreempt|gcDrainFlushBgCredit)
@@ -1593,7 +1862,7 @@
 	if p != nil && !p.gcw.empty() {
 		return true
 	}
-	if atomic.Load64(&work.full) != 0 {
+	if !work.full.empty() {
 		return true // global work available
 	}
 	if work.markrootNext < work.markrootJobs {
@@ -1623,24 +1892,22 @@
 	work.ndone = 0
 	work.nproc = uint32(gcprocs())
 
-	if debug.gcrescanstacks == 0 && work.full == 0 && work.nDataRoots+work.nSpanRoots+work.nStackRoots+work.nRescanRoots == 0 {
+	if work.full == 0 && work.nDataRoots+work.nSpanRoots+work.nStackRoots == 0 {
 		// There's no work on the work queue and no root jobs
 		// that can produce work, so don't bother entering the
 		// getfull() barrier.
 		//
-		// With the hybrid barrier enabled, this will be the
-		// situation the vast majority of the time after
-		// concurrent mark. However, we still need a fallback
-		// for STW GC and because there are some known races
-		// that occasionally leave work around for mark
-		// termination.
+		// This will be the situation the vast majority of the
+		// time after concurrent mark. However, we still need
+		// a fallback for STW GC and because there are some
+		// known races that occasionally leave work around for
+		// mark termination.
 		//
 		// We're still hedging our bets here: if we do
 		// accidentally produce some work, we'll still process
 		// it, just not necessarily in parallel.
 		//
-		// TODO(austin): When we eliminate
-		// debug.gcrescanstacks: fix the races, and remove
+		// TODO(austin): Fix the races and and remove
 		// work draining from mark termination so we don't
 		// need the fallback path.
 		work.helperDrainBlock = false
@@ -1704,52 +1971,14 @@
 	// Update the marked heap stat.
 	memstats.heap_marked = work.bytesMarked
 
-	// Trigger the next GC cycle when the allocated heap has grown
-	// by triggerRatio over the marked heap size. Assume that
-	// we're in steady state, so the marked heap size is the
-	// same now as it was at the beginning of the GC cycle.
-	memstats.gc_trigger = uint64(float64(memstats.heap_marked) * (1 + gcController.triggerRatio))
-	if memstats.gc_trigger < heapminimum {
-		memstats.gc_trigger = heapminimum
-	}
-	if int64(memstats.gc_trigger) < 0 {
-		print("next_gc=", memstats.next_gc, " bytesMarked=", work.bytesMarked, " heap_live=", memstats.heap_live, " initialHeapLive=", work.initialHeapLive, "\n")
-		throw("gc_trigger underflow")
-	}
-
 	// Update other GC heap size stats. This must happen after
 	// cachestats (which flushes local statistics to these) and
 	// flushallmcaches (which modifies heap_live).
 	memstats.heap_live = work.bytesMarked
 	memstats.heap_scan = uint64(gcController.scanWork)
 
-	minTrigger := memstats.heap_live + sweepMinHeapDistance*uint64(gcpercent)/100
-	if memstats.gc_trigger < minTrigger {
-		// The allocated heap is already past the trigger.
-		// This can happen if the triggerRatio is very low and
-		// the marked heap is less than the live heap size.
-		//
-		// Concurrent sweep happens in the heap growth from
-		// heap_live to gc_trigger, so bump gc_trigger up to ensure
-		// that concurrent sweep has some heap growth in which
-		// to perform sweeping before we start the next GC
-		// cycle.
-		memstats.gc_trigger = minTrigger
-	}
-
-	// The next GC cycle should finish before the allocated heap
-	// has grown by GOGC/100.
-	memstats.next_gc = memstats.heap_marked + memstats.heap_marked*uint64(gcpercent)/100
-	if gcpercent < 0 {
-		memstats.next_gc = ^uint64(0)
-	}
-	if memstats.next_gc < memstats.gc_trigger {
-		memstats.next_gc = memstats.gc_trigger
-	}
-
 	if trace.enabled {
 		traceHeapAlloc()
-		traceNextGC()
 	}
 }
 
@@ -1767,6 +1996,7 @@
 		// with an empty swept list.
 		throw("non-empty swept list")
 	}
+	mheap_.pagesSwept = 0
 	unlock(&mheap_.lock)
 
 	if !_ConcurrentSweep || mode == gcForceBlockMode {
@@ -1774,35 +2004,23 @@
 		// Record that no proportional sweeping has to happen.
 		lock(&mheap_.lock)
 		mheap_.sweepPagesPerByte = 0
-		mheap_.pagesSwept = 0
 		unlock(&mheap_.lock)
 		// Sweep all spans eagerly.
 		for sweepone() != ^uintptr(0) {
 			sweep.npausesweep++
 		}
-		// Do an additional mProf_GC, because all 'free' events are now real as well.
-		mProf_GC()
-		mProf_GC()
+		// Free workbufs eagerly.
+		prepareFreeWorkbufs()
+		for freeSomeWbufs(false) {
+		}
+		// All "free" events for this mark/sweep cycle have
+		// now happened, so we can make this profile cycle
+		// available immediately.
+		mProf_NextCycle()
+		mProf_Flush()
 		return
 	}
 
-	// Concurrent sweep needs to sweep all of the in-use pages by
-	// the time the allocated heap reaches the GC trigger. Compute
-	// the ratio of in-use pages to sweep per byte allocated.
-	heapDistance := int64(memstats.gc_trigger) - int64(memstats.heap_live)
-	// Add a little margin so rounding errors and concurrent
-	// sweep are less likely to leave pages unswept when GC starts.
-	heapDistance -= 1024 * 1024
-	if heapDistance < _PageSize {
-		// Avoid setting the sweep ratio extremely high
-		heapDistance = _PageSize
-	}
-	lock(&mheap_.lock)
-	mheap_.sweepPagesPerByte = float64(mheap_.pagesInUse) / float64(heapDistance)
-	mheap_.pagesSwept = 0
-	mheap_.spanBytesAlloc = 0
-	unlock(&mheap_.lock)
-
 	// Background sweep.
 	lock(&sweep.lock)
 	if sweep.parked {
@@ -1820,24 +2038,16 @@
 func gcResetMarkState() {
 	// This may be called during a concurrent phase, so make sure
 	// allgs doesn't change.
-	if !(gcphase == _GCoff || gcphase == _GCmarktermination) {
-		// Accessing gcRescan is unsafe.
-		throw("bad GC phase")
-	}
 	lock(&allglock)
 	for _, gp := range allgs {
 		gp.gcscandone = false  // set to true in gcphasework
 		gp.gcscanvalid = false // stack has not been scanned
-		gp.gcRescan = -1
 		gp.gcAssistBytes = 0
 	}
 	unlock(&allglock)
 
-	// Clear rescan list.
-	work.rescan.list = work.rescan.list[:0]
-
 	work.bytesMarked = 0
-	work.initialHeapLive = memstats.heap_live
+	work.initialHeapLive = atomic.Load64(&memstats.heap_live)
 	work.markrootDone = false
 }
 
diff --git a/libgo/go/runtime/mgclarge.go b/libgo/go/runtime/mgclarge.go
new file mode 100644
index 0000000..757e88d
--- /dev/null
+++ b/libgo/go/runtime/mgclarge.go
@@ -0,0 +1,326 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Page heap.
+//
+// See malloc.go for the general overview.
+//
+// Large spans are the subject of this file. Spans consisting of less than
+// _MaxMHeapLists are held in lists of like sized spans. Larger spans
+// are held in a treap. See https://en.wikipedia.org/wiki/Treap or
+// http://faculty.washington.edu/aragon/pubs/rst89.pdf for an overview.
+// sema.go also holds an implementation of a treap.
+//
+// Each treapNode holds a single span. The treap is sorted by page size
+// and for spans of the same size a secondary sort based on start address
+// is done.
+// Spans are returned based on a best fit algorithm and for spans of the same
+// size the one at the lowest address is selected.
+//
+// The primary routines are
+// insert: adds a span to the treap
+// remove: removes the span from that treap that best fits the required size
+// removeSpan: which removes a specific span from the treap
+//
+// _mheap.lock must be held when manipulating this data structure.
+
+package runtime
+
+import (
+	"unsafe"
+)
+
+//go:notinheap
+type mTreap struct {
+	treap *treapNode
+}
+
+//go:notinheap
+type treapNode struct {
+	right     *treapNode // all treapNodes > this treap node
+	left      *treapNode // all treapNodes < this treap node
+	parent    *treapNode // direct parent of this node, nil if root
+	npagesKey uintptr    // number of pages in spanKey, used as primary sort key
+	spanKey   *mspan     // span of size npagesKey, used as secondary sort key
+	priority  uint32     // random number used by treap algorithm keep tree probablistically balanced
+}
+
+func (t *treapNode) init() {
+	t.right = nil
+	t.left = nil
+	t.parent = nil
+	t.spanKey = nil
+	t.npagesKey = 0
+	t.priority = 0
+}
+
+// isSpanInTreap is handy for debugging. One should hold the heap lock, usually
+// mheap_.lock().
+func (t *treapNode) isSpanInTreap(s *mspan) bool {
+	if t == nil {
+		return false
+	}
+	return t.spanKey == s || t.left.isSpanInTreap(s) || t.right.isSpanInTreap(s)
+}
+
+// walkTreap is handy for debugging.
+// Starting at some treapnode t, for example the root, do a depth first preorder walk of
+// the tree executing fn at each treap node. One should hold the heap lock, usually
+// mheap_.lock().
+func (t *treapNode) walkTreap(fn func(tn *treapNode)) {
+	if t == nil {
+		return
+	}
+	fn(t)
+	t.left.walkTreap(fn)
+	t.right.walkTreap(fn)
+}
+
+// checkTreapNode when used in conjunction with walkTreap can usually detect a
+// poorly formed treap.
+func checkTreapNode(t *treapNode) {
+	// lessThan is used to order the treap.
+	// npagesKey and npages are the primary keys.
+	// spanKey and span are the secondary keys.
+	// span == nil (0) will always be lessThan all
+	// spans of the same size.
+	lessThan := func(npages uintptr, s *mspan) bool {
+		if t.npagesKey != npages {
+			return t.npagesKey < npages
+		}
+		// t.npagesKey == npages
+		return uintptr(unsafe.Pointer(t.spanKey)) < uintptr(unsafe.Pointer(s))
+	}
+
+	if t == nil {
+		return
+	}
+	if t.spanKey.npages != t.npagesKey || t.spanKey.next != nil {
+		println("runtime: checkTreapNode treapNode t=", t, "     t.npagesKey=", t.npagesKey,
+			"t.spanKey.npages=", t.spanKey.npages)
+		throw("why does span.npages and treap.ngagesKey do not match?")
+	}
+	if t.left != nil && lessThan(t.left.npagesKey, t.left.spanKey) {
+		throw("t.lessThan(t.left.npagesKey, t.left.spanKey) is not false")
+	}
+	if t.right != nil && !lessThan(t.right.npagesKey, t.right.spanKey) {
+		throw("!t.lessThan(t.left.npagesKey, t.left.spanKey) is not false")
+	}
+}
+
+// insert adds span to the large span treap.
+func (root *mTreap) insert(span *mspan) {
+	npages := span.npages
+	var last *treapNode
+	pt := &root.treap
+	for t := *pt; t != nil; t = *pt {
+		last = t
+		if t.npagesKey < npages {
+			pt = &t.right
+		} else if t.npagesKey > npages {
+			pt = &t.left
+		} else if uintptr(unsafe.Pointer(t.spanKey)) < uintptr(unsafe.Pointer(span)) {
+			// t.npagesKey == npages, so sort on span addresses.
+			pt = &t.right
+		} else if uintptr(unsafe.Pointer(t.spanKey)) > uintptr(unsafe.Pointer(span)) {
+			pt = &t.left
+		} else {
+			throw("inserting span already in treap")
+		}
+	}
+
+	// Add t as new leaf in tree of span size and unique addrs.
+	// The balanced tree is a treap using priority as the random heap priority.
+	// That is, it is a binary tree ordered according to the npagesKey,
+	// but then among the space of possible binary trees respecting those
+	// npagesKeys, it is kept balanced on average by maintaining a heap ordering
+	// on the priority: s.priority <= both s.right.priority and s.right.priority.
+	// https://en.wikipedia.org/wiki/Treap
+	// http://faculty.washington.edu/aragon/pubs/rst89.pdf
+
+	t := (*treapNode)(mheap_.treapalloc.alloc())
+	t.init()
+	t.npagesKey = span.npages
+	t.priority = fastrand()
+	t.spanKey = span
+	t.parent = last
+	*pt = t // t now at a leaf.
+	// Rotate up into tree according to priority.
+	for t.parent != nil && t.parent.priority > t.priority {
+		if t != nil && t.spanKey.npages != t.npagesKey {
+			println("runtime: insert t=", t, "t.npagesKey=", t.npagesKey)
+			println("runtime:      t.spanKey=", t.spanKey, "t.spanKey.npages=", t.spanKey.npages)
+			throw("span and treap sizes do not match?")
+		}
+		if t.parent.left == t {
+			root.rotateRight(t.parent)
+		} else {
+			if t.parent.right != t {
+				throw("treap insert finds a broken treap")
+			}
+			root.rotateLeft(t.parent)
+		}
+	}
+}
+
+func (root *mTreap) removeNode(t *treapNode) *mspan {
+	if t.spanKey.npages != t.npagesKey {
+		throw("span and treap node npages do not match")
+	}
+	result := t.spanKey
+
+	// Rotate t down to be leaf of tree for removal, respecting priorities.
+	for t.right != nil || t.left != nil {
+		if t.right == nil || t.left != nil && t.left.priority < t.right.priority {
+			root.rotateRight(t)
+		} else {
+			root.rotateLeft(t)
+		}
+	}
+	// Remove t, now a leaf.
+	if t.parent != nil {
+		if t.parent.left == t {
+			t.parent.left = nil
+		} else {
+			t.parent.right = nil
+		}
+	} else {
+		root.treap = nil
+	}
+	// Return the found treapNode's span after freeing the treapNode.
+	t.spanKey = nil
+	t.npagesKey = 0
+	mheap_.treapalloc.free(unsafe.Pointer(t))
+	return result
+}
+
+// remove searches for, finds, removes from the treap, and returns the smallest
+// span that can hold npages. If no span has at least npages return nil.
+// This is slightly more complicated than a simple binary tree search
+// since if an exact match is not found the next larger node is
+// returned.
+// If the last node inspected > npagesKey not holding
+// a left node (a smaller npages) is the "best fit" node.
+func (root *mTreap) remove(npages uintptr) *mspan {
+	t := root.treap
+	for t != nil {
+		if t.spanKey == nil {
+			throw("treap node with nil spanKey found")
+		}
+		if t.npagesKey < npages {
+			t = t.right
+		} else if t.left != nil && t.left.npagesKey >= npages {
+			t = t.left
+		} else {
+			result := t.spanKey
+			root.removeNode(t)
+			return result
+		}
+	}
+	return nil
+}
+
+// removeSpan searches for, finds, deletes span along with
+// the associated treap node. If the span is not in the treap
+// then t will eventually be set to nil and the t.spanKey
+// will throw.
+func (root *mTreap) removeSpan(span *mspan) {
+	npages := span.npages
+	t := root.treap
+	for t.spanKey != span {
+		if t.npagesKey < npages {
+			t = t.right
+		} else if t.npagesKey > npages {
+			t = t.left
+		} else if uintptr(unsafe.Pointer(t.spanKey)) < uintptr(unsafe.Pointer(span)) {
+			t = t.right
+		} else if uintptr(unsafe.Pointer(t.spanKey)) > uintptr(unsafe.Pointer(span)) {
+			t = t.left
+		}
+	}
+	root.removeNode(t)
+}
+
+// scavengetreap visits each node in the treap and scavenges the
+// treapNode's span.
+func scavengetreap(treap *treapNode, now, limit uint64) uintptr {
+	if treap == nil {
+		return 0
+	}
+	return scavengeTreapNode(treap, now, limit) +
+		scavengetreap(treap.left, now, limit) +
+		scavengetreap(treap.right, now, limit)
+}
+
+// rotateLeft rotates the tree rooted at node x.
+// turning (x a (y b c)) into (y (x a b) c).
+func (root *mTreap) rotateLeft(x *treapNode) {
+	// p -> (x a (y b c))
+	p := x.parent
+	a, y := x.left, x.right
+	b, c := y.left, y.right
+
+	y.left = x
+	x.parent = y
+	y.right = c
+	if c != nil {
+		c.parent = y
+	}
+	x.left = a
+	if a != nil {
+		a.parent = x
+	}
+	x.right = b
+	if b != nil {
+		b.parent = x
+	}
+
+	y.parent = p
+	if p == nil {
+		root.treap = y
+	} else if p.left == x {
+		p.left = y
+	} else {
+		if p.right != x {
+			throw("large span treap rotateLeft")
+		}
+		p.right = y
+	}
+}
+
+// rotateRight rotates the tree rooted at node y.
+// turning (y (x a b) c) into (x a (y b c)).
+func (root *mTreap) rotateRight(y *treapNode) {
+	// p -> (y (x a b) c)
+	p := y.parent
+	x, c := y.left, y.right
+	a, b := x.left, x.right
+
+	x.left = a
+	if a != nil {
+		a.parent = x
+	}
+	x.right = y
+	y.parent = x
+	y.left = b
+	if b != nil {
+		b.parent = y
+	}
+	y.right = c
+	if c != nil {
+		c.parent = y
+	}
+
+	x.parent = p
+	if p == nil {
+		root.treap = x
+	} else if p.left == y {
+		p.left = x
+	} else {
+		if p.right != y {
+			throw("large span treap rotateRight")
+		}
+		p.right = x
+	}
+}
diff --git a/libgo/go/runtime/mgcmark.go b/libgo/go/runtime/mgcmark.go
index 93252ba..998a830 100644
--- a/libgo/go/runtime/mgcmark.go
+++ b/libgo/go/runtime/mgcmark.go
@@ -93,21 +93,24 @@
 		// termination, allglen isn't changing, so we'll scan
 		// all Gs.
 		work.nStackRoots = int(atomic.Loaduintptr(&allglen))
-		work.nRescanRoots = 0
 	} else {
 		// We've already scanned span roots and kept the scan
 		// up-to-date during concurrent mark.
 		work.nSpanRoots = 0
 
-		// On the second pass of markroot, we're just scanning
-		// dirty stacks. It's safe to access rescan since the
-		// world is stopped.
+		// The hybrid barrier ensures that stacks can't
+		// contain pointers to unmarked objects, so on the
+		// second markroot, there's no need to scan stacks.
 		work.nStackRoots = 0
-		work.nRescanRoots = len(work.rescan.list)
+
+		if debug.gcrescanstacks > 0 {
+			// Scan stacks anyway for debugging.
+			work.nStackRoots = int(atomic.Loaduintptr(&allglen))
+		}
 	}
 
 	work.markrootNext = 0
-	work.markrootJobs = uint32(fixedRootCount + work.nFlushCacheRoots + work.nDataRoots + work.nSpanRoots + work.nStackRoots + work.nRescanRoots)
+	work.markrootJobs = uint32(fixedRootCount + work.nFlushCacheRoots + work.nDataRoots + work.nSpanRoots + work.nStackRoots)
 }
 
 // gcMarkRootCheck checks that all roots have been scanned. It is
@@ -165,8 +168,7 @@
 	baseData := baseFlushCache + uint32(work.nFlushCacheRoots)
 	baseSpans := baseData + uint32(work.nDataRoots)
 	baseStacks := baseSpans + uint32(work.nSpanRoots)
-	baseRescan := baseStacks + uint32(work.nStackRoots)
-	end := baseRescan + uint32(work.nRescanRoots)
+	end := baseStacks + uint32(work.nStackRoots)
 
 	// Note: if you add a case here, please also update heapdump.go:dumproots.
 	switch {
@@ -186,6 +188,11 @@
 		}
 
 	case i == fixedRootFinalizers:
+		// Only do this once per GC cycle since we don't call
+		// queuefinalizer during marking.
+		if work.markrootDone {
+			break
+		}
 		for fb := allfin; fb != nil; fb = fb.alllink {
 			cnt := uintptr(atomic.Load(&fb.cnt))
 			scanblock(uintptr(unsafe.Pointer(&fb.fin[0])), cnt*unsafe.Sizeof(fb.fin[0]), &finptrmask[0], gcw)
@@ -201,15 +208,8 @@
 	default:
 		// the rest is scanning goroutine stacks
 		var gp *g
-		if baseStacks <= i && i < baseRescan {
+		if baseStacks <= i && i < end {
 			gp = allgs[i-baseStacks]
-		} else if baseRescan <= i && i < end {
-			gp = work.rescan.list[i-baseRescan].ptr()
-			if gp.gcRescan != int32(i-baseRescan) {
-				// Looking for issue #17099.
-				println("runtime: gp", gp, "found at rescan index", i-baseRescan, "but should be at", gp.gcRescan)
-				throw("bad g rescan index")
-			}
 		} else {
 			throw("markroot: bad index")
 		}
@@ -352,6 +352,7 @@
 		return
 	}
 
+	traced := false
 retry:
 	// Compute the amount of scan work we need to do to make the
 	// balance positive. When the required amount of work is low,
@@ -387,10 +388,18 @@
 		if scanWork == 0 {
 			// We were able to steal all of the credit we
 			// needed.
+			if traced {
+				traceGCMarkAssistDone()
+			}
 			return
 		}
 	}
 
+	if trace.enabled && !traced {
+		traced = true
+		traceGCMarkAssistStart()
+	}
+
 	// Perform assist work
 	systemstack(func() {
 		gcAssistAlloc1(gp, scanWork)
@@ -433,6 +442,9 @@
 		// At this point either background GC has satisfied
 		// this G's assist debt, or the GC cycle is over.
 	}
+	if traced {
+		traceGCMarkAssistDone()
+	}
 }
 
 // gcAssistAlloc1 is the part of gcAssistAlloc that runs on the system
@@ -656,10 +668,6 @@
 
 // scanstack scans gp's stack, greying all pointers found on the stack.
 //
-// During mark phase, it also installs stack barriers while traversing
-// gp's stack. During mark termination, it stops scanning when it
-// reaches an unhit stack barrier.
-//
 // scanstack is marked go:systemstack because it must not be preempted
 // while using a workbuf.
 //
@@ -699,84 +707,9 @@
 	scanstackblock(uintptr(unsafe.Pointer(&gp.gcregs)), unsafe.Sizeof(gp.gcregs), gcw)
 	scanstackblock(uintptr(unsafe.Pointer(&gp.context)), unsafe.Sizeof(gp.context), gcw)
 
-	if gcphase == _GCmark {
-		// gp may have added itself to the rescan list between
-		// when GC started and now. It's clean now, so remove
-		// it. This isn't safe during mark termination because
-		// mark termination is consuming this list, but it's
-		// also not necessary.
-		dequeueRescan(gp)
-	}
 	gp.gcscanvalid = true
 }
 
-// queueRescan adds gp to the stack rescan list and clears
-// gp.gcscanvalid. The caller must own gp and ensure that gp isn't
-// already on the rescan list.
-func queueRescan(gp *g) {
-	if debug.gcrescanstacks == 0 {
-		// Clear gcscanvalid to keep assertions happy.
-		//
-		// TODO: Remove gcscanvalid entirely when we remove
-		// stack rescanning.
-		gp.gcscanvalid = false
-		return
-	}
-
-	if gcphase == _GCoff {
-		gp.gcscanvalid = false
-		return
-	}
-	if gp.gcRescan != -1 {
-		throw("g already on rescan list")
-	}
-
-	lock(&work.rescan.lock)
-	gp.gcscanvalid = false
-
-	// Recheck gcphase under the lock in case there was a phase change.
-	if gcphase == _GCoff {
-		unlock(&work.rescan.lock)
-		return
-	}
-	if len(work.rescan.list) == cap(work.rescan.list) {
-		throw("rescan list overflow")
-	}
-	n := len(work.rescan.list)
-	gp.gcRescan = int32(n)
-	work.rescan.list = work.rescan.list[:n+1]
-	work.rescan.list[n].set(gp)
-	unlock(&work.rescan.lock)
-}
-
-// dequeueRescan removes gp from the stack rescan list, if gp is on
-// the rescan list. The caller must own gp.
-func dequeueRescan(gp *g) {
-	if debug.gcrescanstacks == 0 {
-		return
-	}
-
-	if gp.gcRescan == -1 {
-		return
-	}
-	if gcphase == _GCoff {
-		gp.gcRescan = -1
-		return
-	}
-
-	lock(&work.rescan.lock)
-	if work.rescan.list[gp.gcRescan].ptr() != gp {
-		throw("bad dequeueRescan")
-	}
-	// Careful: gp may itself be the last G on the list.
-	last := work.rescan.list[len(work.rescan.list)-1]
-	work.rescan.list[gp.gcRescan] = last
-	last.ptr().gcRescan = gp.gcRescan
-	gp.gcRescan = -1
-	work.rescan.list = work.rescan.list[:len(work.rescan.list)-1]
-	unlock(&work.rescan.lock)
-}
-
 type gcDrainFlags int
 
 const (
@@ -1052,7 +985,7 @@
 			// paths), in which case we must *not* enqueue
 			// oblets since their bitmaps will be
 			// uninitialized.
-			if !hbits.hasPointers(n) {
+			if s.spanclass.noscan() {
 				// Bypass the whole scan.
 				gcw.bytesMarked += uint64(n)
 				return
@@ -1185,6 +1118,7 @@
 			// Dump the object
 			gcDumpObject("obj", obj, ^uintptr(0))
 
+			getg().m.traceback = 2
 			throw("checkmark found unmarked object")
 		}
 		if hbits.isCheckmarked(span.elemsize) {
@@ -1206,6 +1140,7 @@
 			print("runtime: marking free object ", hex(obj), " found at *(", hex(base), "+", hex(off), ")\n")
 			gcDumpObject("base", base, off)
 			gcDumpObject("obj", obj, ^uintptr(0))
+			getg().m.traceback = 2
 			throw("marking free object")
 		}
 
@@ -1217,7 +1152,7 @@
 		atomic.Or8(mbits.bytep, mbits.mask)
 		// If this is a noscan object, fast-track it to black
 		// instead of greying it.
-		if !hbits.hasPointers(span.elemsize) {
+		if span.spanclass.noscan() {
 			gcw.bytesMarked += uint64(span.elemsize)
 			return
 		}
@@ -1250,7 +1185,7 @@
 		print(" s=nil\n")
 		return
 	}
-	print(" s.base()=", hex(s.base()), " s.limit=", hex(s.limit), " s.sizeclass=", s.sizeclass, " s.elemsize=", s.elemsize, " s.state=")
+	print(" s.base()=", hex(s.base()), " s.limit=", hex(s.limit), " s.spanclass=", s.spanclass, " s.elemsize=", s.elemsize, " s.state=")
 	if 0 <= s.state && int(s.state) < len(mSpanStateNames) {
 		print(mSpanStateNames[s.state], "\n")
 	} else {
@@ -1259,7 +1194,7 @@
 
 	skipped := false
 	size := s.elemsize
-	if s.state == _MSpanStack && size == 0 {
+	if s.state == _MSpanManual && size == 0 {
 		// We're printing something from a stack frame. We
 		// don't know how big it is, so just show up to an
 		// including off.
diff --git a/libgo/go/runtime/mgcsweep.go b/libgo/go/runtime/mgcsweep.go
index 2b698bf..c60214c 100644
--- a/libgo/go/runtime/mgcsweep.go
+++ b/libgo/go/runtime/mgcsweep.go
@@ -22,10 +22,6 @@
 
 	nbgsweep    uint32
 	npausesweep uint32
-
-	// pacertracegen is the sweepgen at which the last pacer trace
-	// "sweep finished" message was printed.
-	pacertracegen uint32
 }
 
 // finishsweep_m ensures that all spans are swept.
@@ -62,6 +58,9 @@
 			sweep.nbgsweep++
 			Gosched()
 		}
+		for freeSomeWbufs(true) {
+			Gosched()
+		}
 		lock(&sweep.lock)
 		if !gosweepdone() {
 			// This can happen if a GC runs between
@@ -80,20 +79,24 @@
 //go:nowritebarrier
 func sweepone() uintptr {
 	_g_ := getg()
+	sweepRatio := mheap_.sweepPagesPerByte // For debugging
 
 	// increment locks to ensure that the goroutine is not preempted
 	// in the middle of sweep thus leaving the span in an inconsistent state for next GC
 	_g_.m.locks++
+	if atomic.Load(&mheap_.sweepdone) != 0 {
+		_g_.m.locks--
+		return ^uintptr(0)
+	}
+	atomic.Xadd(&mheap_.sweepers, +1)
+
+	npages := ^uintptr(0)
 	sg := mheap_.sweepgen
 	for {
 		s := mheap_.sweepSpans[1-sg/2%2].pop()
 		if s == nil {
-			mheap_.sweepdone = 1
-			_g_.m.locks--
-			if debug.gcpacertrace > 0 && atomic.Cas(&sweep.pacertracegen, sg-2, sg) {
-				print("pacer: sweep done at heap size ", memstats.heap_live>>20, "MB; allocated ", mheap_.spanBytesAlloc>>20, "MB of spans; swept ", mheap_.pagesSwept, " pages at ", mheap_.sweepPagesPerByte, " pages/byte\n")
-			}
-			return ^uintptr(0)
+			atomic.Store(&mheap_.sweepdone, 1)
+			break
 		}
 		if s.state != mSpanInUse {
 			// This can happen if direct sweeping already
@@ -108,16 +111,25 @@
 		if s.sweepgen != sg-2 || !atomic.Cas(&s.sweepgen, sg-2, sg-1) {
 			continue
 		}
-		npages := s.npages
+		npages = s.npages
 		if !s.sweep(false) {
 			// Span is still in-use, so this returned no
 			// pages to the heap and the span needs to
 			// move to the swept in-use list.
 			npages = 0
 		}
-		_g_.m.locks--
-		return npages
+		break
 	}
+
+	// Decrement the number of active sweepers and if this is the
+	// last one print trace information.
+	if atomic.Xadd(&mheap_.sweepers, -1) == 0 && atomic.Load(&mheap_.sweepdone) != 0 {
+		if debug.gcpacertrace > 0 {
+			print("pacer: sweep done at heap size ", memstats.heap_live>>20, "MB; allocated ", (memstats.heap_live-mheap_.sweepHeapLiveBasis)>>20, "MB during sweep; swept ", mheap_.pagesSwept, " pages at ", sweepRatio, " pages/byte\n")
+		}
+	}
+	_g_.m.locks--
+	return npages
 }
 
 //go:nowritebarrier
@@ -180,15 +192,14 @@
 	}
 
 	if trace.enabled {
-		traceGCSweepStart()
+		traceGCSweepSpan(s.npages * _PageSize)
 	}
 
 	atomic.Xadd64(&mheap_.pagesSwept, int64(s.npages))
 
-	cl := s.sizeclass
+	spc := s.spanclass
 	size := s.elemsize
 	res := false
-	nfree := 0
 
 	c := _g_.m.mcache
 	freeToHeap := false
@@ -278,12 +289,11 @@
 	}
 
 	// Count the number of free objects in this span.
-	nfree = s.countFree()
-	if cl == 0 && nfree != 0 {
+	nalloc := uint16(s.countAlloc())
+	if spc.sizeclass() == 0 && nalloc == 0 {
 		s.needzero = 1
 		freeToHeap = true
 	}
-	nalloc := uint16(s.nelems) - uint16(nfree)
 	nfreed := s.allocCount - nalloc
 
 	// This test is not reliable with gccgo, because of
@@ -300,13 +310,16 @@
 	// unnecessarily, but provided the pointer is not really live
 	// it is not otherwise a problem. So we disable the test for gccgo.
 	if false && nalloc > s.allocCount {
-		print("runtime: nelems=", s.nelems, " nfree=", nfree, " nalloc=", nalloc, " previous allocCount=", s.allocCount, " nfreed=", nfreed, "\n")
+		print("runtime: nelems=", s.nelems, " nalloc=", nalloc, " previous allocCount=", s.allocCount, " nfreed=", nfreed, "\n")
 		throw("sweep increased allocation count")
 	}
 
 	s.allocCount = nalloc
 	wasempty := s.nextFreeIndex() == s.nelems
 	s.freeindex = 0 // reset allocation index to start of span.
+	if trace.enabled {
+		getg().m.p.ptr().traceReclaimed += uintptr(nfreed) * s.elemsize
+	}
 
 	// gcmarkBits becomes the allocBits.
 	// get a fresh cleared gcmarkBits in preparation for next GC
@@ -334,9 +347,9 @@
 		atomic.Store(&s.sweepgen, sweepgen)
 	}
 
-	if nfreed > 0 && cl != 0 {
-		c.local_nsmallfree[cl] += uintptr(nfreed)
-		res = mheap_.central[cl].mcentral.freeSpan(s, preserve, wasempty)
+	if nfreed > 0 && spc.sizeclass() != 0 {
+		c.local_nsmallfree[spc.sizeclass()] += uintptr(nfreed)
+		res = mheap_.central[spc].mcentral.freeSpan(s, preserve, wasempty)
 		// MCentral_FreeSpan updates sweepgen
 	} else if freeToHeap {
 		// Free large span to heap
@@ -370,9 +383,6 @@
 		// it on the swept in-use list.
 		mheap_.sweepSpans[sweepgen/2%2].push(s)
 	}
-	if trace.enabled {
-		traceGCSweepDone()
-	}
 	return res
 }
 
@@ -385,8 +395,7 @@
 //
 // deductSweepCredit makes a worst-case assumption that all spanBytes
 // bytes of the ultimately allocated span will be available for object
-// allocation. The caller should call reimburseSweepCredit if that
-// turns out not to be the case once the span is allocated.
+// allocation.
 //
 // deductSweepCredit is the core of the "proportional sweep" system.
 // It uses statistics gathered by the garbage collector to perform
@@ -400,31 +409,28 @@
 		return
 	}
 
-	// Account for this span allocation.
-	spanBytesAlloc := atomic.Xadd64(&mheap_.spanBytesAlloc, int64(spanBytes))
+	if trace.enabled {
+		traceGCSweepStart()
+	}
+
+retry:
+	sweptBasis := atomic.Load64(&mheap_.pagesSweptBasis)
 
 	// Fix debt if necessary.
-	pagesOwed := int64(mheap_.sweepPagesPerByte * float64(spanBytesAlloc))
-	for pagesOwed-int64(atomic.Load64(&mheap_.pagesSwept)) > int64(callerSweepPages) {
+	newHeapLive := uintptr(atomic.Load64(&memstats.heap_live)-mheap_.sweepHeapLiveBasis) + spanBytes
+	pagesTarget := int64(mheap_.sweepPagesPerByte*float64(newHeapLive)) - int64(callerSweepPages)
+	for pagesTarget > int64(atomic.Load64(&mheap_.pagesSwept)-sweptBasis) {
 		if gosweepone() == ^uintptr(0) {
 			mheap_.sweepPagesPerByte = 0
 			break
 		}
+		if atomic.Load64(&mheap_.pagesSweptBasis) != sweptBasis {
+			// Sweep pacing changed. Recompute debt.
+			goto retry
+		}
 	}
-}
 
-// reimburseSweepCredit records that unusableBytes bytes of a
-// just-allocated span are not available for object allocation. This
-// offsets the worst-case charge performed by deductSweepCredit.
-func reimburseSweepCredit(unusableBytes uintptr) {
-	if mheap_.sweepPagesPerByte == 0 {
-		// Nobody cares about the credit. Avoid the atomic.
-		return
-	}
-	nval := atomic.Xadd64(&mheap_.spanBytesAlloc, -int64(unusableBytes))
-	if int64(nval) < 0 {
-		// Debugging for #18043.
-		print("runtime: bad spanBytesAlloc=", nval, " (was ", nval+uint64(unusableBytes), ") unusableBytes=", unusableBytes, " sweepPagesPerByte=", mheap_.sweepPagesPerByte, "\n")
-		throw("spanBytesAlloc underflow")
+	if trace.enabled {
+		traceGCSweepDone()
 	}
 }
diff --git a/libgo/go/runtime/mgcwork.go b/libgo/go/runtime/mgcwork.go
index 5eb05a7..461679b 100644
--- a/libgo/go/runtime/mgcwork.go
+++ b/libgo/go/runtime/mgcwork.go
@@ -12,8 +12,22 @@
 
 const (
 	_WorkbufSize = 2048 // in bytes; larger values result in less contention
+
+	// workbufAlloc is the number of bytes to allocate at a time
+	// for new workbufs. This must be a multiple of pageSize and
+	// should be a multiple of _WorkbufSize.
+	//
+	// Larger values reduce workbuf allocation overhead. Smaller
+	// values reduce heap fragmentation.
+	workbufAlloc = 32 << 10
 )
 
+func init() {
+	if workbufAlloc%pageSize != 0 || workbufAlloc%_WorkbufSize != 0 {
+		throw("bad workbufAlloc")
+	}
+}
+
 // Garbage collector work pool abstraction.
 //
 // This implements a producer/consumer model for pointers to grey
@@ -25,21 +39,6 @@
 // grey objects, thus blackening them, and then scans them,
 // potentially producing new pointers to grey objects.
 
-// A wbufptr holds a workbuf*, but protects it from write barriers.
-// workbufs never live on the heap, so write barriers are unnecessary.
-// Write barriers on workbuf pointers may also be dangerous in the GC.
-//
-// TODO: Since workbuf is now go:notinheap, this isn't necessary.
-type wbufptr uintptr
-
-func wbufptrOf(w *workbuf) wbufptr {
-	return wbufptr(unsafe.Pointer(w))
-}
-
-func (wp wbufptr) ptr() *workbuf {
-	return (*workbuf)(unsafe.Pointer(wp))
-}
-
 // A gcWork provides the interface to produce and consume work for the
 // garbage collector.
 //
@@ -75,7 +74,7 @@
 	// next.
 	//
 	// Invariant: Both wbuf1 and wbuf2 are nil or neither are.
-	wbuf1, wbuf2 wbufptr
+	wbuf1, wbuf2 *workbuf
 
 	// Bytes marked (blackened) on this gcWork. This is aggregated
 	// into work.bytesMarked by dispose.
@@ -87,12 +86,12 @@
 }
 
 func (w *gcWork) init() {
-	w.wbuf1 = wbufptrOf(getempty())
+	w.wbuf1 = getempty()
 	wbuf2 := trygetfull()
 	if wbuf2 == nil {
 		wbuf2 = getempty()
 	}
-	w.wbuf2 = wbufptrOf(wbuf2)
+	w.wbuf2 = wbuf2
 }
 
 // put enqueues a pointer for the garbage collector to trace.
@@ -100,18 +99,18 @@
 //go:nowritebarrier
 func (w *gcWork) put(obj uintptr) {
 	flushed := false
-	wbuf := w.wbuf1.ptr()
+	wbuf := w.wbuf1
 	if wbuf == nil {
 		w.init()
-		wbuf = w.wbuf1.ptr()
+		wbuf = w.wbuf1
 		// wbuf is empty at this point.
 	} else if wbuf.nobj == len(wbuf.obj) {
 		w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1
-		wbuf = w.wbuf1.ptr()
+		wbuf = w.wbuf1
 		if wbuf.nobj == len(wbuf.obj) {
 			putfull(wbuf)
 			wbuf = getempty()
-			w.wbuf1 = wbufptrOf(wbuf)
+			w.wbuf1 = wbuf
 			flushed = true
 		}
 	}
@@ -132,7 +131,7 @@
 // otherwise it returns false and the caller needs to call put.
 //go:nowritebarrier
 func (w *gcWork) putFast(obj uintptr) bool {
-	wbuf := w.wbuf1.ptr()
+	wbuf := w.wbuf1
 	if wbuf == nil {
 		return false
 	} else if wbuf.nobj == len(wbuf.obj) {
@@ -151,15 +150,15 @@
 // other gcWork instances or other caches.
 //go:nowritebarrier
 func (w *gcWork) tryGet() uintptr {
-	wbuf := w.wbuf1.ptr()
+	wbuf := w.wbuf1
 	if wbuf == nil {
 		w.init()
-		wbuf = w.wbuf1.ptr()
+		wbuf = w.wbuf1
 		// wbuf is empty at this point.
 	}
 	if wbuf.nobj == 0 {
 		w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1
-		wbuf = w.wbuf1.ptr()
+		wbuf = w.wbuf1
 		if wbuf.nobj == 0 {
 			owbuf := wbuf
 			wbuf = trygetfull()
@@ -167,7 +166,7 @@
 				return 0
 			}
 			putempty(owbuf)
-			w.wbuf1 = wbufptrOf(wbuf)
+			w.wbuf1 = wbuf
 		}
 	}
 
@@ -180,7 +179,7 @@
 // the caller is expected to call tryGet().
 //go:nowritebarrier
 func (w *gcWork) tryGetFast() uintptr {
-	wbuf := w.wbuf1.ptr()
+	wbuf := w.wbuf1
 	if wbuf == nil {
 		return 0
 	}
@@ -197,15 +196,15 @@
 // been retrieved.  get returns 0 if there are no pointers remaining.
 //go:nowritebarrier
 func (w *gcWork) get() uintptr {
-	wbuf := w.wbuf1.ptr()
+	wbuf := w.wbuf1
 	if wbuf == nil {
 		w.init()
-		wbuf = w.wbuf1.ptr()
+		wbuf = w.wbuf1
 		// wbuf is empty at this point.
 	}
 	if wbuf.nobj == 0 {
 		w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1
-		wbuf = w.wbuf1.ptr()
+		wbuf = w.wbuf1
 		if wbuf.nobj == 0 {
 			owbuf := wbuf
 			wbuf = getfull()
@@ -213,7 +212,7 @@
 				return 0
 			}
 			putempty(owbuf)
-			w.wbuf1 = wbufptrOf(wbuf)
+			w.wbuf1 = wbuf
 		}
 	}
 
@@ -231,21 +230,21 @@
 //
 //go:nowritebarrier
 func (w *gcWork) dispose() {
-	if wbuf := w.wbuf1.ptr(); wbuf != nil {
+	if wbuf := w.wbuf1; wbuf != nil {
 		if wbuf.nobj == 0 {
 			putempty(wbuf)
 		} else {
 			putfull(wbuf)
 		}
-		w.wbuf1 = 0
+		w.wbuf1 = nil
 
-		wbuf = w.wbuf2.ptr()
+		wbuf = w.wbuf2
 		if wbuf.nobj == 0 {
 			putempty(wbuf)
 		} else {
 			putfull(wbuf)
 		}
-		w.wbuf2 = 0
+		w.wbuf2 = nil
 	}
 	if w.bytesMarked != 0 {
 		// dispose happens relatively infrequently. If this
@@ -265,14 +264,14 @@
 // global queue.
 //go:nowritebarrier
 func (w *gcWork) balance() {
-	if w.wbuf1 == 0 {
+	if w.wbuf1 == nil {
 		return
 	}
-	if wbuf := w.wbuf2.ptr(); wbuf.nobj != 0 {
+	if wbuf := w.wbuf2; wbuf.nobj != 0 {
 		putfull(wbuf)
-		w.wbuf2 = wbufptrOf(getempty())
-	} else if wbuf := w.wbuf1.ptr(); wbuf.nobj > 4 {
-		w.wbuf1 = wbufptrOf(handoff(wbuf))
+		w.wbuf2 = getempty()
+	} else if wbuf := w.wbuf1; wbuf.nobj > 4 {
+		w.wbuf1 = handoff(wbuf)
 	} else {
 		return
 	}
@@ -285,7 +284,7 @@
 // empty returns true if w has no mark work available.
 //go:nowritebarrier
 func (w *gcWork) empty() bool {
-	return w.wbuf1 == 0 || (w.wbuf1.ptr().nobj == 0 && w.wbuf2.ptr().nobj == 0)
+	return w.wbuf1 == nil || (w.wbuf1.nobj == 0 && w.wbuf2.nobj == 0)
 }
 
 // Internally, the GC work pool is kept in arrays in work buffers.
@@ -327,23 +326,56 @@
 func getempty() *workbuf {
 	var b *workbuf
 	if work.empty != 0 {
-		b = (*workbuf)(lfstackpop(&work.empty))
+		b = (*workbuf)(work.empty.pop())
 		if b != nil {
 			b.checkempty()
 		}
 	}
 	if b == nil {
-		b = (*workbuf)(persistentalloc(unsafe.Sizeof(*b), sys.CacheLineSize, &memstats.gc_sys))
+		// Allocate more workbufs.
+		var s *mspan
+		if work.wbufSpans.free.first != nil {
+			lock(&work.wbufSpans.lock)
+			s = work.wbufSpans.free.first
+			if s != nil {
+				work.wbufSpans.free.remove(s)
+				work.wbufSpans.busy.insert(s)
+			}
+			unlock(&work.wbufSpans.lock)
+		}
+		if s == nil {
+			systemstack(func() {
+				s = mheap_.allocManual(workbufAlloc/pageSize, &memstats.gc_sys)
+			})
+			if s == nil {
+				throw("out of memory")
+			}
+			// Record the new span in the busy list.
+			lock(&work.wbufSpans.lock)
+			work.wbufSpans.busy.insert(s)
+			unlock(&work.wbufSpans.lock)
+		}
+		// Slice up the span into new workbufs. Return one and
+		// put the rest on the empty list.
+		for i := uintptr(0); i+_WorkbufSize <= workbufAlloc; i += _WorkbufSize {
+			newb := (*workbuf)(unsafe.Pointer(s.base() + i))
+			newb.nobj = 0
+			if i == 0 {
+				b = newb
+			} else {
+				putempty(newb)
+			}
+		}
 	}
 	return b
 }
 
 // putempty puts a workbuf onto the work.empty list.
-// Upon entry this go routine owns b. The lfstackpush relinquishes ownership.
+// Upon entry this go routine owns b. The lfstack.push relinquishes ownership.
 //go:nowritebarrier
 func putempty(b *workbuf) {
 	b.checkempty()
-	lfstackpush(&work.empty, &b.node)
+	work.empty.push(&b.node)
 }
 
 // putfull puts the workbuf on the work.full list for the GC.
@@ -352,14 +384,14 @@
 //go:nowritebarrier
 func putfull(b *workbuf) {
 	b.checknonempty()
-	lfstackpush(&work.full, &b.node)
+	work.full.push(&b.node)
 }
 
 // trygetfull tries to get a full or partially empty workbuffer.
 // If one is not immediately available return nil
 //go:nowritebarrier
 func trygetfull() *workbuf {
-	b := (*workbuf)(lfstackpop(&work.full))
+	b := (*workbuf)(work.full.pop())
 	if b != nil {
 		b.checknonempty()
 		return b
@@ -380,7 +412,7 @@
 // phase.
 //go:nowritebarrier
 func getfull() *workbuf {
-	b := (*workbuf)(lfstackpop(&work.full))
+	b := (*workbuf)(work.full.pop())
 	if b != nil {
 		b.checknonempty()
 		return b
@@ -398,7 +430,7 @@
 				println("runtime: work.nwait=", decnwait, "work.nproc=", work.nproc)
 				throw("work.nwait > work.nproc")
 			}
-			b = (*workbuf)(lfstackpop(&work.full))
+			b = (*workbuf)(work.full.pop())
 			if b != nil {
 				b.checknonempty()
 				return b
@@ -412,15 +444,11 @@
 		if work.nwait == work.nproc && work.markrootNext >= work.markrootJobs {
 			return nil
 		}
-		_g_ := getg()
 		if i < 10 {
-			_g_.m.gcstats.nprocyield++
 			procyield(20)
 		} else if i < 20 {
-			_g_.m.gcstats.nosyield++
 			osyield()
 		} else {
-			_g_.m.gcstats.nsleep++
 			usleep(100)
 		}
 	}
@@ -434,11 +462,49 @@
 	b.nobj -= n
 	b1.nobj = n
 	memmove(unsafe.Pointer(&b1.obj[0]), unsafe.Pointer(&b.obj[b.nobj]), uintptr(n)*unsafe.Sizeof(b1.obj[0]))
-	_g_ := getg()
-	_g_.m.gcstats.nhandoff++
-	_g_.m.gcstats.nhandoffcnt += uint64(n)
 
 	// Put b on full list - let first half of b get stolen.
 	putfull(b)
 	return b1
 }
+
+// prepareFreeWorkbufs moves busy workbuf spans to free list so they
+// can be freed to the heap. This must only be called when all
+// workbufs are on the empty list.
+func prepareFreeWorkbufs() {
+	lock(&work.wbufSpans.lock)
+	if work.full != 0 {
+		throw("cannot free workbufs when work.full != 0")
+	}
+	// Since all workbufs are on the empty list, we don't care
+	// which ones are in which spans. We can wipe the entire empty
+	// list and move all workbuf spans to the free list.
+	work.empty = 0
+	work.wbufSpans.free.takeAll(&work.wbufSpans.busy)
+	unlock(&work.wbufSpans.lock)
+}
+
+// freeSomeWbufs frees some workbufs back to the heap and returns
+// true if it should be called again to free more.
+func freeSomeWbufs(preemptible bool) bool {
+	const batchSize = 64 // ~1–2 µs per span.
+	lock(&work.wbufSpans.lock)
+	if gcphase != _GCoff || work.wbufSpans.free.isEmpty() {
+		unlock(&work.wbufSpans.lock)
+		return false
+	}
+	systemstack(func() {
+		gp := getg().m.curg
+		for i := 0; i < batchSize && !(preemptible && gp.preempt); i++ {
+			span := work.wbufSpans.free.first
+			if span == nil {
+				break
+			}
+			work.wbufSpans.free.remove(span)
+			mheap_.freeManual(span, &memstats.gc_sys)
+		}
+	})
+	more := !work.wbufSpans.free.isEmpty()
+	unlock(&work.wbufSpans.lock)
+	return more
+}
diff --git a/libgo/go/runtime/mheap.go b/libgo/go/runtime/mheap.go
index 7262748..8749f97 100644
--- a/libgo/go/runtime/mheap.go
+++ b/libgo/go/runtime/mheap.go
@@ -29,12 +29,13 @@
 //go:notinheap
 type mheap struct {
 	lock      mutex
-	free      [_MaxMHeapList]mSpanList // free lists of given length
-	freelarge mSpanList                // free lists length >= _MaxMHeapList
-	busy      [_MaxMHeapList]mSpanList // busy lists of large objects of given length
-	busylarge mSpanList                // busy lists of large objects length >= _MaxMHeapList
+	free      [_MaxMHeapList]mSpanList // free lists of given length up to _MaxMHeapList
+	freelarge mTreap                   // free treap of length >= _MaxMHeapList
+	busy      [_MaxMHeapList]mSpanList // busy lists of large spans of given length
+	busylarge mSpanList                // busy lists of large spans length >= _MaxMHeapList
 	sweepgen  uint32                   // sweep generation, see comment in mspan
 	sweepdone uint32                   // all spans are swept
+	sweepers  uint32                   // number of active sweepone calls
 
 	// allspans is a slice of all mspans ever created. Each mspan
 	// appears exactly once.
@@ -74,37 +75,82 @@
 	_ uint32 // align uint64 fields on 32-bit for atomics
 
 	// Proportional sweep
-	pagesInUse        uint64  // pages of spans in stats _MSpanInUse; R/W with mheap.lock
-	spanBytesAlloc    uint64  // bytes of spans allocated this cycle; updated atomically
-	pagesSwept        uint64  // pages swept this cycle; updated atomically
-	sweepPagesPerByte float64 // proportional sweep ratio; written with lock, read without
+	//
+	// These parameters represent a linear function from heap_live
+	// to page sweep count. The proportional sweep system works to
+	// stay in the black by keeping the current page sweep count
+	// above this line at the current heap_live.
+	//
+	// The line has slope sweepPagesPerByte and passes through a
+	// basis point at (sweepHeapLiveBasis, pagesSweptBasis). At
+	// any given time, the system is at (memstats.heap_live,
+	// pagesSwept) in this space.
+	//
+	// It's important that the line pass through a point we
+	// control rather than simply starting at a (0,0) origin
+	// because that lets us adjust sweep pacing at any time while
+	// accounting for current progress. If we could only adjust
+	// the slope, it would create a discontinuity in debt if any
+	// progress has already been made.
+	pagesInUse         uint64  // pages of spans in stats _MSpanInUse; R/W with mheap.lock
+	pagesSwept         uint64  // pages swept this cycle; updated atomically
+	pagesSweptBasis    uint64  // pagesSwept to use as the origin of the sweep ratio; updated atomically
+	sweepHeapLiveBasis uint64  // value of heap_live to use as the origin of sweep ratio; written with lock, read without
+	sweepPagesPerByte  float64 // proportional sweep ratio; written with lock, read without
 	// TODO(austin): pagesInUse should be a uintptr, but the 386
 	// compiler can't 8-byte align fields.
 
 	// Malloc stats.
-	largefree  uint64                  // bytes freed for large objects (>maxsmallsize)
-	nlargefree uint64                  // number of frees for large objects (>maxsmallsize)
-	nsmallfree [_NumSizeClasses]uint64 // number of frees for small objects (<=maxsmallsize)
+	largealloc  uint64                  // bytes allocated for large objects
+	nlargealloc uint64                  // number of large object allocations
+	largefree   uint64                  // bytes freed for large objects (>maxsmallsize)
+	nlargefree  uint64                  // number of frees for large objects (>maxsmallsize)
+	nsmallfree  [_NumSizeClasses]uint64 // number of frees for small objects (<=maxsmallsize)
 
 	// range of addresses we might see in the heap
-	bitmap         uintptr // Points to one byte past the end of the bitmap
-	bitmap_mapped  uintptr
-	arena_start    uintptr
-	arena_used     uintptr // always mHeap_Map{Bits,Spans} before updating
-	arena_end      uintptr
+	bitmap        uintptr // Points to one byte past the end of the bitmap
+	bitmap_mapped uintptr
+
+	// The arena_* fields indicate the addresses of the Go heap.
+	//
+	// The maximum range of the Go heap is
+	// [arena_start, arena_start+_MaxMem+1).
+	//
+	// The range of the current Go heap is
+	// [arena_start, arena_used). Parts of this range may not be
+	// mapped, but the metadata structures are always mapped for
+	// the full range.
+	arena_start uintptr
+	arena_used  uintptr // Set with setArenaUsed.
+
+	// The heap is grown using a linear allocator that allocates
+	// from the block [arena_alloc, arena_end). arena_alloc is
+	// often, but *not always* equal to arena_used.
+	arena_alloc uintptr
+	arena_end   uintptr
+
+	// arena_reserved indicates that the memory [arena_alloc,
+	// arena_end) is reserved (e.g., mapped PROT_NONE). If this is
+	// false, we have to be careful not to clobber existing
+	// mappings here. If this is true, then we own the mapping
+	// here and *must* clobber it to use it.
 	arena_reserved bool
 
+	_ uint32 // ensure 64-bit alignment
+
 	// central free lists for small size classes.
 	// the padding makes sure that the MCentrals are
 	// spaced CacheLineSize bytes apart, so that each MCentral.lock
 	// gets its own cache line.
-	central [_NumSizeClasses]struct {
+	// central is indexed by spanClass.
+	central [numSpanClasses]struct {
 		mcentral mcentral
-		pad      [sys.CacheLineSize]byte
+		pad      [sys.CacheLineSize - unsafe.Sizeof(mcentral{})%sys.CacheLineSize]byte
 	}
 
 	spanalloc             fixalloc // allocator for span*
 	cachealloc            fixalloc // allocator for mcache*
+	treapalloc            fixalloc // allocator for treapNodes* used by large objects
 	specialfinalizeralloc fixalloc // allocator for specialfinalizer*
 	specialprofilealloc   fixalloc // allocator for specialprofile*
 	speciallock           mutex    // lock for special record allocators.
@@ -117,7 +163,7 @@
 // When a MSpan is in the heap free list, state == MSpanFree
 // and heapmap(s->start) == span, heapmap(s->start+s->npages-1) == span.
 //
-// When a MSpan is allocated, state == MSpanInUse or MSpanStack
+// When a MSpan is allocated, state == MSpanInUse or MSpanManual
 // and heapmap(i) == span for all s->start <= i < s->start+s->npages.
 
 // Every MSpan is in one doubly-linked list,
@@ -125,25 +171,25 @@
 // MCentral's span lists.
 
 // An MSpan representing actual memory has state _MSpanInUse,
-// _MSpanStack, or _MSpanFree. Transitions between these states are
+// _MSpanManual, or _MSpanFree. Transitions between these states are
 // constrained as follows:
 //
-// * A span may transition from free to in-use or stack during any GC
+// * A span may transition from free to in-use or manual during any GC
 //   phase.
 //
 // * During sweeping (gcphase == _GCoff), a span may transition from
-//   in-use to free (as a result of sweeping) or stack to free (as a
+//   in-use to free (as a result of sweeping) or manual to free (as a
 //   result of stacks being freed).
 //
 // * During GC (gcphase != _GCoff), a span *must not* transition from
-//   stack or in-use to free. Because concurrent GC may read a pointer
+//   manual or in-use to free. Because concurrent GC may read a pointer
 //   and then look up its span, the span state must be monotonic.
 type mSpanState uint8
 
 const (
-	_MSpanDead  mSpanState = iota
-	_MSpanInUse            // allocated for garbage collected heap
-	_MSpanStack            // allocated for use by stack allocator
+	_MSpanDead   mSpanState = iota
+	_MSpanInUse             // allocated for garbage collected heap
+	_MSpanManual            // allocated for manual management (e.g., stack allocator)
 	_MSpanFree
 )
 
@@ -152,7 +198,7 @@
 var mSpanStateNames = []string{
 	"_MSpanDead",
 	"_MSpanInUse",
-	"_MSpanStack",
+	"_MSpanManual",
 	"_MSpanFree",
 }
 
@@ -170,15 +216,16 @@
 	prev *mspan     // previous span in list, or nil if none
 	list *mSpanList // For debugging. TODO: Remove.
 
-	startAddr     uintptr   // address of first byte of span aka s.base()
-	npages        uintptr   // number of pages in span
-	stackfreelist gclinkptr // list of free stacks, avoids overloading freelist
+	startAddr uintptr // address of first byte of span aka s.base()
+	npages    uintptr // number of pages in span
+
+	manualFreeList gclinkptr // list of free objects in _MSpanManual spans
 
 	// freeindex is the slot index between 0 and nelems at which to begin scanning
 	// for the next free object in this span.
 	// Each allocation scans allocBits starting at freeindex until it encounters a 0
 	// indicating a free object. freeindex is then adjusted so that subsequent scans begin
-	// just past the the newly discovered free object.
+	// just past the newly discovered free object.
 	//
 	// If freeindex == nelem, this span has no free objects.
 	//
@@ -224,8 +271,8 @@
 	// The sweep will free the old allocBits and set allocBits to the
 	// gcmarkBits. The gcmarkBits are replaced with a fresh zeroed
 	// out memory.
-	allocBits  *uint8
-	gcmarkBits *uint8
+	allocBits  *gcBits
+	gcmarkBits *gcBits
 
 	// sweep generation:
 	// if sweepgen == h->sweepgen - 2, the span needs sweeping
@@ -236,8 +283,8 @@
 	sweepgen    uint32
 	divMul      uint16     // for divide by elemsize - divMagic.mul
 	baseMask    uint16     // if non-0, elemsize is a power of 2, & this will get object allocation base
-	allocCount  uint16     // capacity - number of objects in freelist
-	sizeclass   uint8      // size class
+	allocCount  uint16     // number of allocated objects
+	spanclass   spanClass  // size class and noscan (uint8)
 	incache     bool       // being used by an mcache
 	state       mSpanState // mspaninuse etc
 	needzero    uint8      // needs to be zeroed before allocation
@@ -292,8 +339,33 @@
 	h.allspans = append(h.allspans, s)
 }
 
+// A spanClass represents the size class and noscan-ness of a span.
+//
+// Each size class has a noscan spanClass and a scan spanClass. The
+// noscan spanClass contains only noscan objects, which do not contain
+// pointers and thus do not need to be scanned by the garbage
+// collector.
+type spanClass uint8
+
+const (
+	numSpanClasses = _NumSizeClasses << 1
+	tinySpanClass  = spanClass(tinySizeClass<<1 | 1)
+)
+
+func makeSpanClass(sizeclass uint8, noscan bool) spanClass {
+	return spanClass(sizeclass<<1) | spanClass(bool2int(noscan))
+}
+
+func (sc spanClass) sizeclass() int8 {
+	return int8(sc >> 1)
+}
+
+func (sc spanClass) noscan() bool {
+	return sc&1 != 0
+}
+
 // inheap reports whether b is a pointer into a (potentially dead) heap object.
-// It returns false for pointers into stack spans.
+// It returns false for pointers into _MSpanManual spans.
 // Non-preemptible because it is used by write barriers.
 //go:nowritebarrier
 //go:nosplit
@@ -309,7 +381,9 @@
 	return true
 }
 
-// inHeapOrStack is a variant of inheap that returns true for pointers into stack spans.
+// inHeapOrStack is a variant of inheap that returns true for pointers
+// into any allocated heap span.
+//
 //go:nowritebarrier
 //go:nosplit
 func inHeapOrStack(b uintptr) bool {
@@ -322,10 +396,8 @@
 		return false
 	}
 	switch s.state {
-	case mSpanInUse:
+	case mSpanInUse, _MSpanManual:
 		return b < s.limit
-	case _MSpanStack:
-		return b < s.base()+s.npages<<_PageShift
 	default:
 		return false
 	}
@@ -376,7 +448,7 @@
 	}
 
 	p := s.base()
-	if s.sizeclass == 0 {
+	if s.spanclass.sizeclass() == 0 {
 		// Large object.
 		if base != nil {
 			*base = p
@@ -401,6 +473,7 @@
 
 // Initialize the heap.
 func (h *mheap) init(spansStart, spansBytes uintptr) {
+	h.treapalloc.init(unsafe.Sizeof(treapNode{}), nil, nil, &memstats.other_sys)
 	h.spanalloc.init(unsafe.Sizeof(mspan{}), recordspan, unsafe.Pointer(h), &memstats.mspan_sys)
 	h.cachealloc.init(unsafe.Sizeof(mcache{}), nil, nil, &memstats.mcache_sys)
 	h.specialfinalizeralloc.init(unsafe.Sizeof(specialfinalizer{}), nil, nil, &memstats.other_sys)
@@ -421,26 +494,51 @@
 		h.busy[i].init()
 	}
 
-	h.freelarge.init()
 	h.busylarge.init()
 	for i := range h.central {
-		h.central[i].mcentral.init(int32(i))
+		h.central[i].mcentral.init(spanClass(i))
 	}
 
 	sp := (*slice)(unsafe.Pointer(&h.spans))
 	sp.array = unsafe.Pointer(spansStart)
 	sp.len = 0
 	sp.cap = int(spansBytes / sys.PtrSize)
+
+	// Map metadata structures. But don't map race detector memory
+	// since we're not actually growing the arena here (and TSAN
+	// gets mad if you map 0 bytes).
+	h.setArenaUsed(h.arena_used, false)
 }
 
-// mHeap_MapSpans makes sure that the spans are mapped
+// setArenaUsed extends the usable arena to address arena_used and
+// maps auxiliary VM regions for any newly usable arena space.
+//
+// racemap indicates that this memory should be managed by the race
+// detector. racemap should be true unless this is covering a VM hole.
+func (h *mheap) setArenaUsed(arena_used uintptr, racemap bool) {
+	// Map auxiliary structures *before* h.arena_used is updated.
+	// Waiting to update arena_used until after the memory has been mapped
+	// avoids faults when other threads try access these regions immediately
+	// after observing the change to arena_used.
+
+	// Map the bitmap.
+	h.mapBits(arena_used)
+
+	// Map spans array.
+	h.mapSpans(arena_used)
+
+	// Tell the race detector about the new heap memory.
+	if racemap && raceenabled {
+		racemapshadow(unsafe.Pointer(h.arena_used), arena_used-h.arena_used)
+	}
+
+	h.arena_used = arena_used
+}
+
+// mapSpans makes sure that the spans are mapped
 // up to the new value of arena_used.
 //
-// It must be called with the expected new value of arena_used,
-// *before* h.arena_used has been updated.
-// Waiting to update arena_used until after the memory has been mapped
-// avoids faults when other threads try access the bitmap immediately
-// after observing the change to arena_used.
+// Don't call this directly. Call mheap.setArenaUsed.
 func (h *mheap) mapSpans(arena_used uintptr) {
 	// Map spans array, PageSize at a time.
 	n := arena_used
@@ -466,7 +564,7 @@
 		if s.sweepgen == sg-2 && atomic.Cas(&s.sweepgen, sg-2, sg-1) {
 			list.remove(s)
 			// swept spans are at the end of the list
-			list.insertBack(s)
+			list.insertBack(s) // Puts it back on a busy list. s is not in the treap at this point.
 			unlock(&h.lock)
 			snpages := s.npages
 			if s.sweep(false) {
@@ -533,7 +631,7 @@
 
 // Allocate a new span of npage pages from the heap for GC'd memory
 // and record its size class in the HeapMap and HeapMapCache.
-func (h *mheap) alloc_m(npage uintptr, sizeclass int32, large bool) *mspan {
+func (h *mheap) alloc_m(npage uintptr, spanclass spanClass, large bool) *mspan {
 	_g_ := getg()
 	lock(&h.lock)
 
@@ -547,7 +645,13 @@
 		// If GC kept a bit for whether there were any marks
 		// in a span, we could release these free spans
 		// at the end of GC and eliminate this entirely.
+		if trace.enabled {
+			traceGCSweepStart()
+		}
 		h.reclaim(npage)
+		if trace.enabled {
+			traceGCSweepDone()
+		}
 	}
 
 	// transfer stats from cache to global
@@ -556,7 +660,7 @@
 	memstats.tinyallocs += uint64(_g_.m.mcache.local_tinyallocs)
 	_g_.m.mcache.local_tinyallocs = 0
 
-	s := h.allocSpanLocked(npage)
+	s := h.allocSpanLocked(npage, &memstats.heap_inuse)
 	if s != nil {
 		// Record span info, because gc needs to be
 		// able to map interior pointer to containing span.
@@ -564,8 +668,8 @@
 		h.sweepSpans[h.sweepgen/2%2].push(s) // Add to swept in-use list.
 		s.state = _MSpanInUse
 		s.allocCount = 0
-		s.sizeclass = uint8(sizeclass)
-		if sizeclass == 0 {
+		s.spanclass = spanclass
+		if sizeclass := spanclass.sizeclass(); sizeclass == 0 {
 			s.elemsize = s.npages << _PageShift
 			s.divShift = 0
 			s.divMul = 0
@@ -584,9 +688,11 @@
 		h.pagesInUse += uint64(npage)
 		if large {
 			memstats.heap_objects++
+			mheap_.largealloc += uint64(s.elemsize)
+			mheap_.nlargealloc++
 			atomic.Xadd64(&memstats.heap_live, int64(npage<<_PageShift))
 			// Swept spans are at the end of lists.
-			if s.npages < uintptr(len(h.free)) {
+			if s.npages < uintptr(len(h.busy)) {
 				h.busy[s.npages].insertBack(s)
 			} else {
 				h.busylarge.insertBack(s)
@@ -615,13 +721,13 @@
 	return s
 }
 
-func (h *mheap) alloc(npage uintptr, sizeclass int32, large bool, needzero bool) *mspan {
+func (h *mheap) alloc(npage uintptr, spanclass spanClass, large bool, needzero bool) *mspan {
 	// Don't do any operations that lock the heap on the G stack.
 	// It might trigger stack growth, and the stack growth code needs
 	// to be able to allocate heap.
 	var s *mspan
 	systemstack(func() {
-		s = h.alloc_m(npage, sizeclass, large)
+		s = h.alloc_m(npage, spanclass, large)
 	})
 
 	if s != nil {
@@ -633,29 +739,46 @@
 	return s
 }
 
-func (h *mheap) allocStack(npage uintptr) *mspan {
-	_g_ := getg()
-	if _g_ != _g_.m.g0 {
-		throw("mheap_allocstack not on g0 stack")
-	}
+// allocManual allocates a manually-managed span of npage pages.
+// allocManual returns nil if allocation fails.
+//
+// allocManual adds the bytes used to *stat, which should be a
+// memstats in-use field. Unlike allocations in the GC'd heap, the
+// allocation does *not* count toward heap_inuse or heap_sys.
+//
+// The memory backing the returned span may not be zeroed if
+// span.needzero is set.
+//
+// allocManual must be called on the system stack to prevent stack
+// growth. Since this is used by the stack allocator, stack growth
+// during allocManual would self-deadlock.
+//
+//go:systemstack
+func (h *mheap) allocManual(npage uintptr, stat *uint64) *mspan {
 	lock(&h.lock)
-	s := h.allocSpanLocked(npage)
+	s := h.allocSpanLocked(npage, stat)
 	if s != nil {
-		s.state = _MSpanStack
-		s.stackfreelist = 0
+		s.state = _MSpanManual
+		s.manualFreeList = 0
 		s.allocCount = 0
-		memstats.stacks_inuse += uint64(s.npages << _PageShift)
+		s.spanclass = 0
+		s.nelems = 0
+		s.elemsize = 0
+		s.limit = s.base() + s.npages<<_PageShift
+		// Manually manged memory doesn't count toward heap_sys.
+		memstats.heap_sys -= uint64(s.npages << _PageShift)
 	}
 
-	// This unlock acts as a release barrier. See mHeap_Alloc_m.
+	// This unlock acts as a release barrier. See mheap.alloc_m.
 	unlock(&h.lock)
+
 	return s
 }
 
 // Allocates a span of the given size.  h must be locked.
 // The returned span has been removed from the
 // free list, but its state is still MSpanFree.
-func (h *mheap) allocSpanLocked(npage uintptr) *mspan {
+func (h *mheap) allocSpanLocked(npage uintptr, stat *uint64) *mspan {
 	var list *mSpanList
 	var s *mspan
 
@@ -664,13 +787,12 @@
 		list = &h.free[i]
 		if !list.isEmpty() {
 			s = list.first
+			list.remove(s)
 			goto HaveSpan
 		}
 	}
-
 	// Best fit in list of large spans.
-	list = &h.freelarge
-	s = h.allocLarge(npage)
+	s = h.allocLarge(npage) // allocLarge removed s from h.freelarge for us
 	if s == nil {
 		if !h.grow(npage) {
 			return nil
@@ -689,10 +811,6 @@
 	if s.npages < npage {
 		throw("MHeap_AllocLocked - bad npages")
 	}
-	list.remove(s)
-	if s.inList() {
-		throw("still in list")
-	}
 	if s.npreleased > 0 {
 		sysUsed(unsafe.Pointer(s.base()), s.npages<<_PageShift)
 		memstats.heap_released -= uint64(s.npreleased << _PageShift)
@@ -711,8 +829,8 @@
 		h.spans[p] = t
 		h.spans[p+t.npages-1] = t
 		t.needzero = s.needzero
-		s.state = _MSpanStack // prevent coalescing with s
-		t.state = _MSpanStack
+		s.state = _MSpanManual // prevent coalescing with s
+		t.state = _MSpanManual
 		h.freeSpanLocked(t, false, false, s.unusedsince)
 		s.state = _MSpanFree
 	}
@@ -723,7 +841,7 @@
 		h.spans[p+n] = s
 	}
 
-	memstats.heap_inuse += uint64(npage << _PageShift)
+	*stat += uint64(npage << _PageShift)
 	memstats.heap_idle -= uint64(npage << _PageShift)
 
 	//println("spanalloc", hex(s.start<<_PageShift))
@@ -733,24 +851,19 @@
 	return s
 }
 
-// Allocate a span of exactly npage pages from the list of large spans.
-func (h *mheap) allocLarge(npage uintptr) *mspan {
-	return bestFit(&h.freelarge, npage, nil)
+// Large spans have a minimum size of 1MByte. The maximum number of large spans to support
+// 1TBytes is 1 million, experimentation using random sizes indicates that the depth of
+// the tree is less that 2x that of a perfectly balanced tree. For 1TByte can be referenced
+// by a perfectly balanced tree with a a depth of 20. Twice that is an acceptable 40.
+func (h *mheap) isLargeSpan(npages uintptr) bool {
+	return npages >= uintptr(len(h.free))
 }
 
-// Search list for smallest span with >= npage pages.
-// If there are multiple smallest spans, take the one
-// with the earliest starting address.
-func bestFit(list *mSpanList, npage uintptr, best *mspan) *mspan {
-	for s := list.first; s != nil; s = s.next {
-		if s.npages < npage {
-			continue
-		}
-		if best == nil || s.npages < best.npages || (s.npages == best.npages && s.base() < best.base()) {
-			best = s
-		}
-	}
-	return best
+// allocLarge allocates a span of at least npage pages from the treap of large spans.
+// Returns nil if no such span currently exists.
+func (h *mheap) allocLarge(npage uintptr) *mspan {
+	// Search treap for smallest span with >= npage pages.
+	return h.freelarge.remove(npage)
 }
 
 // Try to add at least npage pages of memory to the heap,
@@ -849,22 +962,30 @@
 	})
 }
 
-func (h *mheap) freeStack(s *mspan) {
-	_g_ := getg()
-	if _g_ != _g_.m.g0 {
-		throw("mheap_freestack not on g0 stack")
-	}
+// freeManual frees a manually-managed span returned by allocManual.
+// stat must be the same as the stat passed to the allocManual that
+// allocated s.
+//
+// This must only be called when gcphase == _GCoff. See mSpanState for
+// an explanation.
+//
+// freeManual must be called on the system stack to prevent stack
+// growth, just like allocManual.
+//
+//go:systemstack
+func (h *mheap) freeManual(s *mspan, stat *uint64) {
 	s.needzero = 1
 	lock(&h.lock)
-	memstats.stacks_inuse -= uint64(s.npages << _PageShift)
-	h.freeSpanLocked(s, true, true, 0)
+	*stat -= uint64(s.npages << _PageShift)
+	memstats.heap_sys += uint64(s.npages << _PageShift)
+	h.freeSpanLocked(s, false, true, 0)
 	unlock(&h.lock)
 }
 
 // s must be on a busy list (h.busy or h.busylarge) or unlinked.
 func (h *mheap) freeSpanLocked(s *mspan, acctinuse, acctidle bool, unusedsince int64) {
 	switch s.state {
-	case _MSpanStack:
+	case _MSpanManual:
 		if s.allocCount != 0 {
 			throw("MHeap_FreeSpanLocked - invalid stack free")
 		}
@@ -900,50 +1021,98 @@
 	// Coalesce with earlier, later spans.
 	p := (s.base() - h.arena_start) >> _PageShift
 	if p > 0 {
-		t := h.spans[p-1]
-		if t != nil && t.state == _MSpanFree {
-			s.startAddr = t.startAddr
-			s.npages += t.npages
-			s.npreleased = t.npreleased // absorb released pages
-			s.needzero |= t.needzero
-			p -= t.npages
+		before := h.spans[p-1]
+		if before != nil && before.state == _MSpanFree {
+			// Now adjust s.
+			s.startAddr = before.startAddr
+			s.npages += before.npages
+			s.npreleased = before.npreleased // absorb released pages
+			s.needzero |= before.needzero
+			p -= before.npages
 			h.spans[p] = s
-			h.freeList(t.npages).remove(t)
-			t.state = _MSpanDead
-			h.spanalloc.free(unsafe.Pointer(t))
-		}
-	}
-	if (p + s.npages) < uintptr(len(h.spans)) {
-		t := h.spans[p+s.npages]
-		if t != nil && t.state == _MSpanFree {
-			s.npages += t.npages
-			s.npreleased += t.npreleased
-			s.needzero |= t.needzero
-			h.spans[p+s.npages-1] = s
-			h.freeList(t.npages).remove(t)
-			t.state = _MSpanDead
-			h.spanalloc.free(unsafe.Pointer(t))
+			// The size is potentially changing so the treap needs to delete adjacent nodes and
+			// insert back as a combined node.
+			if h.isLargeSpan(before.npages) {
+				// We have a t, it is large so it has to be in the treap so we can remove it.
+				h.freelarge.removeSpan(before)
+			} else {
+				h.freeList(before.npages).remove(before)
+			}
+			before.state = _MSpanDead
+			h.spanalloc.free(unsafe.Pointer(before))
 		}
 	}
 
-	// Insert s into appropriate list.
-	h.freeList(s.npages).insert(s)
+	// Now check to see if next (greater addresses) span is free and can be coalesced.
+	if (p + s.npages) < uintptr(len(h.spans)) {
+		after := h.spans[p+s.npages]
+		if after != nil && after.state == _MSpanFree {
+			s.npages += after.npages
+			s.npreleased += after.npreleased
+			s.needzero |= after.needzero
+			h.spans[p+s.npages-1] = s
+			if h.isLargeSpan(after.npages) {
+				h.freelarge.removeSpan(after)
+			} else {
+				h.freeList(after.npages).remove(after)
+			}
+			after.state = _MSpanDead
+			h.spanalloc.free(unsafe.Pointer(after))
+		}
+	}
+
+	// Insert s into appropriate list or treap.
+	if h.isLargeSpan(s.npages) {
+		h.freelarge.insert(s)
+	} else {
+		h.freeList(s.npages).insert(s)
+	}
 }
 
 func (h *mheap) freeList(npages uintptr) *mSpanList {
-	if npages < uintptr(len(h.free)) {
-		return &h.free[npages]
-	}
-	return &h.freelarge
+	return &h.free[npages]
 }
 
 func (h *mheap) busyList(npages uintptr) *mSpanList {
-	if npages < uintptr(len(h.free)) {
+	if npages < uintptr(len(h.busy)) {
 		return &h.busy[npages]
 	}
 	return &h.busylarge
 }
 
+func scavengeTreapNode(t *treapNode, now, limit uint64) uintptr {
+	s := t.spanKey
+	var sumreleased uintptr
+	if (now-uint64(s.unusedsince)) > limit && s.npreleased != s.npages {
+		start := s.base()
+		end := start + s.npages<<_PageShift
+		if physPageSize > _PageSize {
+			// We can only release pages in
+			// physPageSize blocks, so round start
+			// and end in. (Otherwise, madvise
+			// will round them *out* and release
+			// more memory than we want.)
+			start = (start + physPageSize - 1) &^ (physPageSize - 1)
+			end &^= physPageSize - 1
+			if end <= start {
+				// start and end don't span a
+				// whole physical page.
+				return sumreleased
+			}
+		}
+		len := end - start
+		released := len - (s.npreleased << _PageShift)
+		if physPageSize > _PageSize && released == 0 {
+			return sumreleased
+		}
+		memstats.heap_released += uint64(released)
+		sumreleased += released
+		s.npreleased = len >> _PageShift
+		sysUnused(unsafe.Pointer(start), len)
+	}
+	return sumreleased
+}
+
 func scavengelist(list *mSpanList, now, limit uint64) uintptr {
 	if list.isEmpty() {
 		return 0
@@ -984,27 +1153,31 @@
 }
 
 func (h *mheap) scavenge(k int32, now, limit uint64) {
+	// Disallow malloc or panic while holding the heap lock. We do
+	// this here because this is an non-mallocgc entry-point to
+	// the mheap API.
+	gp := getg()
+	gp.m.mallocing++
 	lock(&h.lock)
 	var sumreleased uintptr
 	for i := 0; i < len(h.free); i++ {
 		sumreleased += scavengelist(&h.free[i], now, limit)
 	}
-	sumreleased += scavengelist(&h.freelarge, now, limit)
+	sumreleased += scavengetreap(h.freelarge.treap, now, limit)
 	unlock(&h.lock)
+	gp.m.mallocing--
 
 	if debug.gctrace > 0 {
 		if sumreleased > 0 {
 			print("scvg", k, ": ", sumreleased>>20, " MB released\n")
 		}
-		// TODO(dvyukov): these stats are incorrect as we don't subtract stack usage from heap.
-		// But we can't call ReadMemStats on g0 holding locks.
 		print("scvg", k, ": inuse: ", memstats.heap_inuse>>20, ", idle: ", memstats.heap_idle>>20, ", sys: ", memstats.heap_sys>>20, ", released: ", memstats.heap_released>>20, ", consumed: ", (memstats.heap_sys-memstats.heap_released)>>20, " (MB)\n")
 	}
 }
 
 //go:linkname runtime_debug_freeOSMemory runtime_debug.freeOSMemory
 func runtime_debug_freeOSMemory() {
-	gcStart(gcForceBlockMode, false)
+	GC()
 	systemstack(func() { mheap_.scavenge(-1, ^uint64(0), 0) })
 }
 
@@ -1017,7 +1190,7 @@
 	span.startAddr = base
 	span.npages = npages
 	span.allocCount = 0
-	span.sizeclass = 0
+	span.spanclass = 0
 	span.incache = false
 	span.elemsize = 0
 	span.state = _MSpanDead
@@ -1043,7 +1216,8 @@
 
 func (list *mSpanList) remove(span *mspan) {
 	if span.list != list {
-		println("runtime: failed MSpanList_Remove", span, span.prev, span.list, list)
+		print("runtime: failed MSpanList_Remove span.npages=", span.npages,
+			" span=", span, " prev=", span.prev, " span.list=", span.list, " list=", list, "\n")
 		throw("MSpanList_Remove")
 	}
 	if list.first == span {
@@ -1085,7 +1259,7 @@
 
 func (list *mSpanList) insertBack(span *mspan) {
 	if span.next != nil || span.prev != nil || span.list != nil {
-		println("failed MSpanList_InsertBack", span, span.next, span.prev, span.list)
+		println("runtime: failed MSpanList_InsertBack", span, span.next, span.prev, span.list)
 		throw("MSpanList_InsertBack")
 	}
 	span.prev = list.last
@@ -1100,6 +1274,31 @@
 	span.list = list
 }
 
+// takeAll removes all spans from other and inserts them at the front
+// of list.
+func (list *mSpanList) takeAll(other *mSpanList) {
+	if other.isEmpty() {
+		return
+	}
+
+	// Reparent everything in other to list.
+	for s := other.first; s != nil; s = s.next {
+		s.list = list
+	}
+
+	// Concatenate the lists.
+	if list.isEmpty() {
+		*list = *other
+	} else {
+		// Neither list is empty. Put other before list.
+		other.last.next = list.first
+		list.first.prev = other.last
+		list.first = other.first
+	}
+
+	other.first, other.last = nil, nil
+}
+
 const (
 	_KindSpecialFinalizer = 1
 	_KindSpecialProfile   = 2
@@ -1311,6 +1510,22 @@
 	}
 }
 
+// gcBits is an alloc/mark bitmap. This is always used as *gcBits.
+//
+//go:notinheap
+type gcBits uint8
+
+// bytep returns a pointer to the n'th byte of b.
+func (b *gcBits) bytep(n uintptr) *uint8 {
+	return addb((*uint8)(b), n)
+}
+
+// bitp returns a pointer to the byte containing bit n and a mask for
+// selecting that bit from *bytep.
+func (b *gcBits) bitp(n uintptr) (bytep *uint8, mask uint8) {
+	return b.bytep(n / 8), 1 << (n % 8)
+}
+
 const gcBitsChunkBytes = uintptr(64 << 10)
 const gcBitsHeaderBytes = unsafe.Sizeof(gcBitsHeader{})
 
@@ -1320,42 +1535,87 @@
 }
 
 //go:notinheap
-type gcBits struct {
+type gcBitsArena struct {
 	// gcBitsHeader // side step recursive type bug (issue 14620) by including fields by hand.
-	free uintptr // free is the index into bits of the next free byte.
-	next *gcBits
-	bits [gcBitsChunkBytes - gcBitsHeaderBytes]uint8
+	free uintptr // free is the index into bits of the next free byte; read/write atomically
+	next *gcBitsArena
+	bits [gcBitsChunkBytes - gcBitsHeaderBytes]gcBits
 }
 
 var gcBitsArenas struct {
 	lock     mutex
-	free     *gcBits
-	next     *gcBits
-	current  *gcBits
-	previous *gcBits
+	free     *gcBitsArena
+	next     *gcBitsArena // Read atomically. Write atomically under lock.
+	current  *gcBitsArena
+	previous *gcBitsArena
+}
+
+// tryAlloc allocates from b or returns nil if b does not have enough room.
+// This is safe to call concurrently.
+func (b *gcBitsArena) tryAlloc(bytes uintptr) *gcBits {
+	if b == nil || atomic.Loaduintptr(&b.free)+bytes > uintptr(len(b.bits)) {
+		return nil
+	}
+	// Try to allocate from this block.
+	end := atomic.Xadduintptr(&b.free, bytes)
+	if end > uintptr(len(b.bits)) {
+		return nil
+	}
+	// There was enough room.
+	start := end - bytes
+	return &b.bits[start]
 }
 
 // newMarkBits returns a pointer to 8 byte aligned bytes
 // to be used for a span's mark bits.
-func newMarkBits(nelems uintptr) *uint8 {
-	lock(&gcBitsArenas.lock)
+func newMarkBits(nelems uintptr) *gcBits {
 	blocksNeeded := uintptr((nelems + 63) / 64)
 	bytesNeeded := blocksNeeded * 8
-	if gcBitsArenas.next == nil ||
-		gcBitsArenas.next.free+bytesNeeded > uintptr(len(gcBits{}.bits)) {
-		// Allocate a new arena.
-		fresh := newArena()
-		fresh.next = gcBitsArenas.next
-		gcBitsArenas.next = fresh
+
+	// Try directly allocating from the current head arena.
+	head := (*gcBitsArena)(atomic.Loadp(unsafe.Pointer(&gcBitsArenas.next)))
+	if p := head.tryAlloc(bytesNeeded); p != nil {
+		return p
 	}
-	if gcBitsArenas.next.free >= gcBitsChunkBytes {
-		println("runtime: gcBitsArenas.next.free=", gcBitsArenas.next.free, gcBitsChunkBytes)
+
+	// There's not enough room in the head arena. We may need to
+	// allocate a new arena.
+	lock(&gcBitsArenas.lock)
+	// Try the head arena again, since it may have changed. Now
+	// that we hold the lock, the list head can't change, but its
+	// free position still can.
+	if p := gcBitsArenas.next.tryAlloc(bytesNeeded); p != nil {
+		unlock(&gcBitsArenas.lock)
+		return p
+	}
+
+	// Allocate a new arena. This may temporarily drop the lock.
+	fresh := newArenaMayUnlock()
+	// If newArenaMayUnlock dropped the lock, another thread may
+	// have put a fresh arena on the "next" list. Try allocating
+	// from next again.
+	if p := gcBitsArenas.next.tryAlloc(bytesNeeded); p != nil {
+		// Put fresh back on the free list.
+		// TODO: Mark it "already zeroed"
+		fresh.next = gcBitsArenas.free
+		gcBitsArenas.free = fresh
+		unlock(&gcBitsArenas.lock)
+		return p
+	}
+
+	// Allocate from the fresh arena. We haven't linked it in yet, so
+	// this cannot race and is guaranteed to succeed.
+	p := fresh.tryAlloc(bytesNeeded)
+	if p == nil {
 		throw("markBits overflow")
 	}
-	result := &gcBitsArenas.next.bits[gcBitsArenas.next.free]
-	gcBitsArenas.next.free += bytesNeeded
+
+	// Add the fresh arena to the "next" list.
+	fresh.next = gcBitsArenas.next
+	atomic.StorepNoWB(unsafe.Pointer(&gcBitsArenas.next), unsafe.Pointer(fresh))
+
 	unlock(&gcBitsArenas.lock)
-	return result
+	return p
 }
 
 // newAllocBits returns a pointer to 8 byte aligned bytes
@@ -1364,7 +1624,7 @@
 // allocation bits. For spans not being initialized the
 // the mark bits are repurposed as allocation bits when
 // the span is swept.
-func newAllocBits(nelems uintptr) *uint8 {
+func newAllocBits(nelems uintptr) *gcBits {
 	return newMarkBits(nelems)
 }
 
@@ -1398,18 +1658,21 @@
 	}
 	gcBitsArenas.previous = gcBitsArenas.current
 	gcBitsArenas.current = gcBitsArenas.next
-	gcBitsArenas.next = nil // newMarkBits calls newArena when needed
+	atomic.StorepNoWB(unsafe.Pointer(&gcBitsArenas.next), nil) // newMarkBits calls newArena when needed
 	unlock(&gcBitsArenas.lock)
 }
 
-// newArena allocates and zeroes a gcBits arena.
-func newArena() *gcBits {
-	var result *gcBits
+// newArenaMayUnlock allocates and zeroes a gcBits arena.
+// The caller must hold gcBitsArena.lock. This may temporarily release it.
+func newArenaMayUnlock() *gcBitsArena {
+	var result *gcBitsArena
 	if gcBitsArenas.free == nil {
-		result = (*gcBits)(sysAlloc(gcBitsChunkBytes, &memstats.gc_sys))
+		unlock(&gcBitsArenas.lock)
+		result = (*gcBitsArena)(sysAlloc(gcBitsChunkBytes, &memstats.gc_sys))
 		if result == nil {
 			throw("runtime: cannot allocate memory")
 		}
+		lock(&gcBitsArenas.lock)
 	} else {
 		result = gcBitsArenas.free
 		gcBitsArenas.free = gcBitsArenas.free.next
@@ -1418,7 +1681,7 @@
 	result.next = nil
 	// If result.bits is not 8 byte aligned adjust index so
 	// that &result.bits[result.free] is 8 byte aligned.
-	if uintptr(unsafe.Offsetof(gcBits{}.bits))&7 == 0 {
+	if uintptr(unsafe.Offsetof(gcBitsArena{}.bits))&7 == 0 {
 		result.free = 0
 	} else {
 		result.free = 8 - (uintptr(unsafe.Pointer(&result.bits[0])) & 7)
diff --git a/libgo/go/runtime/mksizeclasses.go b/libgo/go/runtime/mksizeclasses.go
index 0f897ba..0cb2b33 100644
--- a/libgo/go/runtime/mksizeclasses.go
+++ b/libgo/go/runtime/mksizeclasses.go
@@ -48,7 +48,7 @@
 	flag.Parse()
 
 	var b bytes.Buffer
-	fmt.Fprintln(&b, "// AUTO-GENERATED by mksizeclasses.go; DO NOT EDIT")
+	fmt.Fprintln(&b, "// Code generated by mksizeclasses.go; DO NOT EDIT.")
 	fmt.Fprintln(&b, "//go:generate go run mksizeclasses.go")
 	fmt.Fprintln(&b)
 	fmt.Fprintln(&b, "package runtime")
diff --git a/libgo/go/runtime/mprof.go b/libgo/go/runtime/mprof.go
index 87f84a7..f31c88c 100644
--- a/libgo/go/runtime/mprof.go
+++ b/libgo/go/runtime/mprof.go
@@ -64,27 +64,70 @@
 	// come only after a GC during concurrent sweeping. So if we would
 	// naively count them, we would get a skew toward mallocs.
 	//
-	// Mallocs are accounted in recent stats.
-	// Explicit frees are accounted in recent stats.
-	// GC frees are accounted in prev stats.
-	// After GC prev stats are added to final stats and
-	// recent stats are moved into prev stats.
-	allocs      uintptr
-	frees       uintptr
-	alloc_bytes uintptr
-	free_bytes  uintptr
+	// Hence, we delay information to get consistent snapshots as
+	// of mark termination. Allocations count toward the next mark
+	// termination's snapshot, while sweep frees count toward the
+	// previous mark termination's snapshot:
+	//
+	//              MT          MT          MT          MT
+	//             .·|         .·|         .·|         .·|
+	//          .·˙  |      .·˙  |      .·˙  |      .·˙  |
+	//       .·˙     |   .·˙     |   .·˙     |   .·˙     |
+	//    .·˙        |.·˙        |.·˙        |.·˙        |
+	//
+	//       alloc → ▲ ← free
+	//               ┠┅┅┅┅┅┅┅┅┅┅┅P
+	//       C+2     →    C+1    →  C
+	//
+	//                   alloc → ▲ ← free
+	//                           ┠┅┅┅┅┅┅┅┅┅┅┅P
+	//                   C+2     →    C+1    →  C
+	//
+	// Since we can't publish a consistent snapshot until all of
+	// the sweep frees are accounted for, we wait until the next
+	// mark termination ("MT" above) to publish the previous mark
+	// termination's snapshot ("P" above). To do this, allocation
+	// and free events are accounted to *future* heap profile
+	// cycles ("C+n" above) and we only publish a cycle once all
+	// of the events from that cycle must be done. Specifically:
+	//
+	// Mallocs are accounted to cycle C+2.
+	// Explicit frees are accounted to cycle C+2.
+	// GC frees (done during sweeping) are accounted to cycle C+1.
+	//
+	// After mark termination, we increment the global heap
+	// profile cycle counter and accumulate the stats from cycle C
+	// into the active profile.
 
-	// changes between next-to-last GC and last GC
-	prev_allocs      uintptr
-	prev_frees       uintptr
-	prev_alloc_bytes uintptr
-	prev_free_bytes  uintptr
+	// active is the currently published profile. A profiling
+	// cycle can be accumulated into active once its complete.
+	active memRecordCycle
 
-	// changes since last GC
-	recent_allocs      uintptr
-	recent_frees       uintptr
-	recent_alloc_bytes uintptr
-	recent_free_bytes  uintptr
+	// future records the profile events we're counting for cycles
+	// that have not yet been published. This is ring buffer
+	// indexed by the global heap profile cycle C and stores
+	// cycles C, C+1, and C+2. Unlike active, these counts are
+	// only for a single cycle; they are not cumulative across
+	// cycles.
+	//
+	// We store cycle C here because there's a window between when
+	// C becomes the active cycle and when we've flushed it to
+	// active.
+	future [3]memRecordCycle
+}
+
+// memRecordCycle
+type memRecordCycle struct {
+	allocs, frees           uintptr
+	alloc_bytes, free_bytes uintptr
+}
+
+// add accumulates b into a. It does not zero b.
+func (a *memRecordCycle) add(b *memRecordCycle) {
+	a.allocs += b.allocs
+	a.frees += b.frees
+	a.alloc_bytes += b.alloc_bytes
+	a.free_bytes += b.free_bytes
 }
 
 // A blockRecord is the bucket data for a bucket of type blockProfile,
@@ -100,8 +143,21 @@
 	xbuckets  *bucket // mutex profile buckets
 	buckhash  *[179999]*bucket
 	bucketmem uintptr
+
+	mProf struct {
+		// All fields in mProf are protected by proflock.
+
+		// cycle is the global heap profile cycle. This wraps
+		// at mProfCycleWrap.
+		cycle uint32
+		// flushed indicates that future[cycle] in all buckets
+		// has been flushed to the active profile.
+		flushed bool
+	}
 )
 
+const mProfCycleWrap = uint32(len(memRecord{}.future)) * (2 << 24)
+
 // newBucket allocates a bucket with the given type and number of stack entries.
 func newBucket(typ bucketType, nstk int) *bucket {
 	size := unsafe.Sizeof(bucket{}) + uintptr(nstk)*unsafe.Sizeof(location{})
@@ -212,30 +268,71 @@
 	return true
 }
 
-func mprof_GC() {
+// mProf_NextCycle publishes the next heap profile cycle and creates a
+// fresh heap profile cycle. This operation is fast and can be done
+// during STW. The caller must call mProf_Flush before calling
+// mProf_NextCycle again.
+//
+// This is called by mark termination during STW so allocations and
+// frees after the world is started again count towards a new heap
+// profiling cycle.
+func mProf_NextCycle() {
+	lock(&proflock)
+	// We explicitly wrap mProf.cycle rather than depending on
+	// uint wraparound because the memRecord.future ring does not
+	// itself wrap at a power of two.
+	mProf.cycle = (mProf.cycle + 1) % mProfCycleWrap
+	mProf.flushed = false
+	unlock(&proflock)
+}
+
+// mProf_Flush flushes the events from the current heap profiling
+// cycle into the active profile. After this it is safe to start a new
+// heap profiling cycle with mProf_NextCycle.
+//
+// This is called by GC after mark termination starts the world. In
+// contrast with mProf_NextCycle, this is somewhat expensive, but safe
+// to do concurrently.
+func mProf_Flush() {
+	lock(&proflock)
+	if !mProf.flushed {
+		mProf_FlushLocked()
+		mProf.flushed = true
+	}
+	unlock(&proflock)
+}
+
+func mProf_FlushLocked() {
+	c := mProf.cycle
 	for b := mbuckets; b != nil; b = b.allnext {
 		mp := b.mp()
-		mp.allocs += mp.prev_allocs
-		mp.frees += mp.prev_frees
-		mp.alloc_bytes += mp.prev_alloc_bytes
-		mp.free_bytes += mp.prev_free_bytes
 
-		mp.prev_allocs = mp.recent_allocs
-		mp.prev_frees = mp.recent_frees
-		mp.prev_alloc_bytes = mp.recent_alloc_bytes
-		mp.prev_free_bytes = mp.recent_free_bytes
-
-		mp.recent_allocs = 0
-		mp.recent_frees = 0
-		mp.recent_alloc_bytes = 0
-		mp.recent_free_bytes = 0
+		// Flush cycle C into the published profile and clear
+		// it for reuse.
+		mpc := &mp.future[c%uint32(len(mp.future))]
+		mp.active.add(mpc)
+		*mpc = memRecordCycle{}
 	}
 }
 
-// Record that a gc just happened: all the 'recent' statistics are now real.
-func mProf_GC() {
+// mProf_PostSweep records that all sweep frees for this GC cycle have
+// completed. This has the effect of publishing the heap profile
+// snapshot as of the last mark termination without advancing the heap
+// profile cycle.
+func mProf_PostSweep() {
 	lock(&proflock)
-	mprof_GC()
+	// Flush cycle C+1 to the active profile so everything as of
+	// the last mark termination becomes visible. *Don't* advance
+	// the cycle, since we're still accumulating allocs in cycle
+	// C+2, which have to become C+1 in the next mark termination
+	// and so on.
+	c := mProf.cycle
+	for b := mbuckets; b != nil; b = b.allnext {
+		mp := b.mp()
+		mpc := &mp.future[(c+1)%uint32(len(mp.future))]
+		mp.active.add(mpc)
+		*mpc = memRecordCycle{}
+	}
 	unlock(&proflock)
 }
 
@@ -245,9 +342,11 @@
 	nstk := callers(4, stk[:])
 	lock(&proflock)
 	b := stkbucket(memProfile, size, stk[:nstk], true)
+	c := mProf.cycle
 	mp := b.mp()
-	mp.recent_allocs++
-	mp.recent_alloc_bytes += size
+	mpc := &mp.future[(c+2)%uint32(len(mp.future))]
+	mpc.allocs++
+	mpc.alloc_bytes += size
 	unlock(&proflock)
 
 	// Setprofilebucket locks a bunch of other mutexes, so we call it outside of proflock.
@@ -262,9 +361,11 @@
 // Called when freeing a profiled block.
 func mProf_Free(b *bucket, size uintptr) {
 	lock(&proflock)
+	c := mProf.cycle
 	mp := b.mp()
-	mp.prev_frees++
-	mp.prev_free_bytes += size
+	mpc := &mp.future[(c+1)%uint32(len(mp.future))]
+	mpc.frees++
+	mpc.free_bytes += size
 	unlock(&proflock)
 }
 
@@ -298,7 +399,7 @@
 		cycles = 1
 	}
 	if blocksampled(cycles) {
-		saveblockevent(cycles, skip+1, blockProfile, &blockprofilerate)
+		saveblockevent(cycles, skip+1, blockProfile)
 	}
 }
 
@@ -310,7 +411,7 @@
 	return true
 }
 
-func saveblockevent(cycles int64, skip int, which bucketType, ratep *uint64) {
+func saveblockevent(cycles int64, skip int, which bucketType) {
 	gp := getg()
 	var nstk int
 	var stk [maxStack]location
@@ -355,7 +456,7 @@
 	// TODO(pjw): measure impact of always calling fastrand vs using something
 	// like malloc.go:nextSample()
 	if rate > 0 && int64(fastrand())%rate == 0 {
-		saveblockevent(cycles, skip+1, mutexProfile, &mutexprofilerate)
+		saveblockevent(cycles, skip+1, mutexProfile)
 	}
 }
 
@@ -443,13 +544,17 @@
 // of calling MemProfile directly.
 func MemProfile(p []MemProfileRecord, inuseZero bool) (n int, ok bool) {
 	lock(&proflock)
+	// If we're between mProf_NextCycle and mProf_Flush, take care
+	// of flushing to the active profile so we only have to look
+	// at the active profile below.
+	mProf_FlushLocked()
 	clear := true
 	for b := mbuckets; b != nil; b = b.allnext {
 		mp := b.mp()
-		if inuseZero || mp.alloc_bytes != mp.free_bytes {
+		if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
 			n++
 		}
-		if mp.allocs != 0 || mp.frees != 0 {
+		if mp.active.allocs != 0 || mp.active.frees != 0 {
 			clear = false
 		}
 	}
@@ -457,13 +562,15 @@
 		// Absolutely no data, suggesting that a garbage collection
 		// has not yet happened. In order to allow profiling when
 		// garbage collection is disabled from the beginning of execution,
-		// accumulate stats as if a GC just happened, and recount buckets.
-		mprof_GC()
-		mprof_GC()
+		// accumulate all of the cycles, and recount buckets.
 		n = 0
 		for b := mbuckets; b != nil; b = b.allnext {
 			mp := b.mp()
-			if inuseZero || mp.alloc_bytes != mp.free_bytes {
+			for c := range mp.future {
+				mp.active.add(&mp.future[c])
+				mp.future[c] = memRecordCycle{}
+			}
+			if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
 				n++
 			}
 		}
@@ -473,7 +580,7 @@
 		idx := 0
 		for b := mbuckets; b != nil; b = b.allnext {
 			mp := b.mp()
-			if inuseZero || mp.alloc_bytes != mp.free_bytes {
+			if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
 				record(&p[idx], b)
 				idx++
 			}
@@ -486,10 +593,10 @@
 // Write b's data to r.
 func record(r *MemProfileRecord, b *bucket) {
 	mp := b.mp()
-	r.AllocBytes = int64(mp.alloc_bytes)
-	r.FreeBytes = int64(mp.free_bytes)
-	r.AllocObjects = int64(mp.allocs)
-	r.FreeObjects = int64(mp.frees)
+	r.AllocBytes = int64(mp.active.alloc_bytes)
+	r.FreeBytes = int64(mp.active.free_bytes)
+	r.AllocObjects = int64(mp.active.allocs)
+	r.FreeObjects = int64(mp.active.frees)
 	for i, loc := range b.stk() {
 		if i >= len(r.Stack0) {
 			break
@@ -505,7 +612,7 @@
 	lock(&proflock)
 	for b := mbuckets; b != nil; b = b.allnext {
 		mp := b.mp()
-		fn(b, b.nstk, &b.stk()[0], b.size, mp.allocs, mp.frees)
+		fn(b, b.nstk, &b.stk()[0], b.size, mp.active.allocs, mp.active.frees)
 	}
 	unlock(&proflock)
 }
diff --git a/libgo/go/runtime/msize.go b/libgo/go/runtime/msize.go
index 438c987..0accb83 100644
--- a/libgo/go/runtime/msize.go
+++ b/libgo/go/runtime/msize.go
@@ -9,28 +9,6 @@
 
 package runtime
 
-// sizeToClass(0 <= n <= MaxSmallSize) returns the size class,
-//	1 <= sizeclass < NumSizeClasses, for n.
-//	Size class 0 is reserved to mean "not small".
-//
-// The sizeToClass lookup is implemented using two arrays,
-// one mapping sizes <= 1024 to their class and one mapping
-// sizes >= 1024 and <= MaxSmallSize to their class.
-// All objects are 8-aligned, so the first array is indexed by
-// the size divided by 8 (rounded up).  Objects >= 1024 bytes
-// are 128-aligned, so the second array is indexed by the
-// size divided by 128 (rounded up).  The arrays are constants
-// in sizeclass.go generated by mksizeclass.go.
-func sizeToClass(size uint32) uint32 {
-	if size > _MaxSmallSize {
-		throw("invalid size")
-	}
-	if size > smallSizeMax-8 {
-		return uint32(size_to_class128[(size-smallSizeMax+largeSizeDiv-1)/largeSizeDiv])
-	}
-	return uint32(size_to_class8[(size+smallSizeDiv-1)/smallSizeDiv])
-}
-
 // Returns size of the memory block that mallocgc will allocate if you ask for the size.
 func roundupsize(size uintptr) uintptr {
 	if size < _MaxSmallSize {
diff --git a/libgo/go/runtime/mstats.go b/libgo/go/runtime/mstats.go
index aa3cfef..71dc223 100644
--- a/libgo/go/runtime/mstats.go
+++ b/libgo/go/runtime/mstats.go
@@ -33,13 +33,12 @@
 	// Statistics about malloc heap.
 	// Protected by mheap.lock
 	//
-	// In mstats, heap_sys and heap_inuse includes stack memory,
-	// while in MemStats stack memory is separated out from the
-	// heap stats.
+	// Like MemStats, heap_sys and heap_inuse do not count memory
+	// in manually-managed spans.
 	heap_alloc    uint64 // bytes allocated and not yet freed (same as alloc above)
-	heap_sys      uint64 // virtual address space obtained from system
+	heap_sys      uint64 // virtual address space obtained from system for GC'd heap
 	heap_idle     uint64 // bytes in idle spans
-	heap_inuse    uint64 // bytes in non-idle spans
+	heap_inuse    uint64 // bytes in _MSpanInUse spans
 	heap_released uint64 // bytes released to the os
 	heap_objects  uint64 // total number of allocated objects
 
@@ -59,7 +58,7 @@
 
 	// Statistics about allocation of low-level fixed-size structures.
 	// Protected by FixAlloc locks.
-	stacks_inuse uint64 // this number is included in heap_inuse above; differs from MemStats.StackInuse
+	stacks_inuse uint64 // bytes in manually-managed stack spans
 	stacks_sys   uint64 // only counts newosproc0 stack in mstats; differs from MemStats.StackSys
 	mspan_inuse  uint64 // mspan structures
 	mspan_sys    uint64
@@ -72,7 +71,7 @@
 	// Statistics about garbage collector.
 	// Protected by mheap or stopping the world during GC.
 	next_gc         uint64 // goal heap_live for when next GC ends; ^0 if disabled
-	last_gc         uint64 // last gc (in absolute time)
+	last_gc_unix    uint64 // last gc (in unix time)
 	pause_total_ns  uint64
 	pause_ns        [256]uint64 // circular buffer of recent gc pause lengths
 	pause_end       [256]uint64 // circular buffer of recent gc end times (nanoseconds since 1970)
@@ -92,13 +91,26 @@
 
 	// Statistics below here are not exported to MemStats directly.
 
-	tinyallocs uint64 // number of tiny allocations that didn't cause actual allocation; not exported to go directly
+	last_gc_nanotime uint64 // last gc (monotonic time)
+	tinyallocs       uint64 // number of tiny allocations that didn't cause actual allocation; not exported to go directly
+
+	// triggerRatio is the heap growth ratio that triggers marking.
+	//
+	// E.g., if this is 0.6, then GC should start when the live
+	// heap has reached 1.6 times the heap size marked by the
+	// previous cycle. This should be ≤ GOGC/100 so the trigger
+	// heap size is less than the goal heap size. This is set
+	// during mark termination for the next cycle's trigger.
+	triggerRatio float64
 
 	// gc_trigger is the heap size that triggers marking.
 	//
 	// When heap_live ≥ gc_trigger, the mark phase will start.
 	// This is also the heap size by which proportional sweeping
 	// must be complete.
+	//
+	// This is computed from triggerRatio during mark termination
+	// for the next cycle's trigger.
 	gc_trigger uint64
 
 	// heap_live is the number of bytes considered live by the GC.
@@ -121,6 +133,8 @@
 	// leads to a conservative GC rate rather than a GC rate that
 	// is potentially too low.
 	//
+	// Reads should likewise be atomic (or during STW).
+	//
 	// Whenever this is updated, call traceHeapAlloc() and
 	// gcController.revise().
 	heap_live uint64
@@ -451,22 +465,18 @@
 }
 
 func readmemstats_m(stats *MemStats) {
-	updatememstats(nil)
+	updatememstats()
 
 	// The size of the trailing by_size array differs between
 	// mstats and MemStats. NumSizeClasses was changed, but we
 	// cannot change MemStats because of backward compatibility.
 	memmove(unsafe.Pointer(stats), unsafe.Pointer(&memstats), sizeof_C_MStats)
 
-	// Stack numbers are part of the heap numbers, separate those out for user consumption
+	// memstats.stacks_sys is only memory mapped directly for OS stacks.
+	// Add in heap-allocated stack memory for user consumption.
 	stats.StackSys += stats.StackInuse
-	stats.HeapInuse -= stats.StackInuse
-	stats.HeapSys -= stats.StackInuse
 }
 
-// For gccgo this is in runtime/mgc0.c.
-func updatememstats(stats *gcstats)
-
 //go:linkname readGCStats runtime_debug.readGCStats
 func readGCStats(pauses *[]uint64) {
 	systemstack(func() {
@@ -500,7 +510,7 @@
 		p[n+i] = memstats.pause_end[j]
 	}
 
-	p[n+n] = memstats.last_gc
+	p[n+n] = memstats.last_gc_unix
 	p[n+n+1] = uint64(memstats.numgc)
 	p[n+n+2] = memstats.pause_total_ns
 	unlock(&mheap_.lock)
@@ -508,26 +518,15 @@
 }
 
 //go:nowritebarrier
-func updatememstats(stats *gcstats) {
-	if stats != nil {
-		*stats = gcstats{}
-	}
-	for mp := allm; mp != nil; mp = mp.alllink {
-		if stats != nil {
-			src := (*[unsafe.Sizeof(gcstats{}) / 8]uint64)(unsafe.Pointer(&mp.gcstats))
-			dst := (*[unsafe.Sizeof(gcstats{}) / 8]uint64)(unsafe.Pointer(stats))
-			for i, v := range src {
-				dst[i] += v
-			}
-			mp.gcstats = gcstats{}
-		}
-	}
-
+func updatememstats() {
 	memstats.mcache_inuse = uint64(mheap_.cachealloc.inuse)
 	memstats.mspan_inuse = uint64(mheap_.spanalloc.inuse)
 	memstats.sys = memstats.heap_sys + memstats.stacks_sys + memstats.mspan_sys +
 		memstats.mcache_sys + memstats.buckhash_sys + memstats.gc_sys + memstats.other_sys
 
+	// We also count stacks_inuse as sys memory.
+	memstats.sys += memstats.stacks_inuse
+
 	// Calculate memory allocator stats.
 	// During program execution we only count number of frees and amount of freed memory.
 	// Current number of alive object in the heap and amount of alive heap memory
@@ -550,45 +549,49 @@
 	// Aggregate local stats.
 	cachestats()
 
-	// Scan all spans and count number of alive objects.
-	lock(&mheap_.lock)
-	for _, s := range mheap_.allspans {
-		if s.state != mSpanInUse {
+	// Collect allocation stats. This is safe and consistent
+	// because the world is stopped.
+	var smallFree, totalAlloc, totalFree uint64
+	// Collect per-spanclass stats.
+	for spc := range mheap_.central {
+		// The mcaches are now empty, so mcentral stats are
+		// up-to-date.
+		c := &mheap_.central[spc].mcentral
+		memstats.nmalloc += c.nmalloc
+		i := spanClass(spc).sizeclass()
+		memstats.by_size[i].nmalloc += c.nmalloc
+		totalAlloc += c.nmalloc * uint64(class_to_size[i])
+	}
+	// Collect per-sizeclass stats.
+	for i := 0; i < _NumSizeClasses; i++ {
+		if i == 0 {
+			memstats.nmalloc += mheap_.nlargealloc
+			totalAlloc += mheap_.largealloc
+			totalFree += mheap_.largefree
+			memstats.nfree += mheap_.nlargefree
 			continue
 		}
-		if s.sizeclass == 0 {
-			memstats.nmalloc++
-			memstats.alloc += uint64(s.elemsize)
-		} else {
-			memstats.nmalloc += uint64(s.allocCount)
-			memstats.by_size[s.sizeclass].nmalloc += uint64(s.allocCount)
-			memstats.alloc += uint64(s.allocCount) * uint64(s.elemsize)
-		}
-	}
-	unlock(&mheap_.lock)
 
-	// Aggregate by size class.
-	smallfree := uint64(0)
-	memstats.nfree = mheap_.nlargefree
-	for i := 0; i < len(memstats.by_size); i++ {
+		// The mcache stats have been flushed to mheap_.
 		memstats.nfree += mheap_.nsmallfree[i]
 		memstats.by_size[i].nfree = mheap_.nsmallfree[i]
-		memstats.by_size[i].nmalloc += mheap_.nsmallfree[i]
-		smallfree += mheap_.nsmallfree[i] * uint64(class_to_size[i])
+		smallFree += mheap_.nsmallfree[i] * uint64(class_to_size[i])
 	}
+	totalFree += smallFree
+
 	memstats.nfree += memstats.tinyallocs
-	memstats.nmalloc += memstats.nfree
+	memstats.nmalloc += memstats.tinyallocs
 
 	// Calculate derived stats.
-	memstats.total_alloc = memstats.alloc + mheap_.largefree + smallfree
+	memstats.total_alloc = totalAlloc
+	memstats.alloc = totalAlloc - totalFree
 	memstats.heap_alloc = memstats.alloc
 	memstats.heap_objects = memstats.nmalloc - memstats.nfree
 }
 
 //go:nowritebarrier
 func cachestats() {
-	for i := 0; ; i++ {
-		p := allp[i]
+	for _, p := range &allp {
 		if p == nil {
 			break
 		}
diff --git a/libgo/go/runtime/mstkbar.go b/libgo/go/runtime/mstkbar.go
deleted file mode 100644
index 616c220..0000000
--- a/libgo/go/runtime/mstkbar.go
+++ /dev/null
@@ -1,395 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build ignore
-
-// Garbage collector: stack barriers
-//
-// Stack barriers enable the garbage collector to determine how much
-// of a gorountine stack has changed between when a stack is scanned
-// during the concurrent scan phase and when it is re-scanned during
-// the stop-the-world mark termination phase. Mark termination only
-// needs to re-scan the changed part, so for deep stacks this can
-// significantly reduce GC pause time compared to the alternative of
-// re-scanning whole stacks. The deeper the stacks, the more stack
-// barriers help.
-//
-// When stacks are scanned during the concurrent scan phase, the stack
-// scan installs stack barriers by selecting stack frames and
-// overwriting the saved return PCs (or link registers) of these
-// frames with the PC of a "stack barrier trampoline". Later, when a
-// selected frame returns, it "returns" to this trampoline instead of
-// returning to its actual caller. The trampoline records that the
-// stack has unwound past this frame and jumps to the original return
-// PC recorded when the stack barrier was installed. Mark termination
-// re-scans only as far as the first frame that hasn't hit a stack
-// barrier and then removes and un-hit stack barriers.
-//
-// This scheme is very lightweight. No special code is required in the
-// mutator to record stack unwinding and the trampoline is only a few
-// assembly instructions.
-//
-// Book-keeping
-// ------------
-//
-// The primary cost of stack barriers is book-keeping: the runtime has
-// to record the locations of all stack barriers and the original
-// return PCs in order to return to the correct caller when a stack
-// barrier is hit and so it can remove un-hit stack barriers. In order
-// to minimize this cost, the Go runtime places stack barriers in
-// exponentially-spaced frames, starting 1K past the current frame.
-// The book-keeping structure hence grows logarithmically with the
-// size of the stack and mark termination re-scans at most twice as
-// much stack as necessary.
-//
-// The runtime reserves space for this book-keeping structure at the
-// top of the stack allocation itself (just above the outermost
-// frame). This is necessary because the regular memory allocator can
-// itself grow the stack, and hence can't be used when allocating
-// stack-related structures.
-//
-// For debugging, the runtime also supports installing stack barriers
-// at every frame. However, this requires significantly more
-// book-keeping space.
-//
-// Correctness
-// -----------
-//
-// The runtime and the compiler cooperate to ensure that all objects
-// reachable from the stack as of mark termination are marked.
-// Anything unchanged since the concurrent scan phase will be marked
-// because it is marked by the concurrent scan. After the concurrent
-// scan, there are three possible classes of stack modifications that
-// must be tracked:
-//
-// 1) Mutator writes below the lowest un-hit stack barrier. This
-// includes all writes performed by an executing function to its own
-// stack frame. This part of the stack will be re-scanned by mark
-// termination, which will mark any objects made reachable from
-// modifications to this part of the stack.
-//
-// 2) Mutator writes above the lowest un-hit stack barrier. It's
-// possible for a mutator to modify the stack above the lowest un-hit
-// stack barrier if a higher frame has passed down a pointer to a
-// stack variable in its frame. This is called an "up-pointer". The
-// compiler ensures that writes through up-pointers have an
-// accompanying write barrier (it simply doesn't distinguish between
-// writes through up-pointers and writes through heap pointers). This
-// write barrier marks any object made reachable from modifications to
-// this part of the stack.
-//
-// 3) Runtime writes to the stack. Various runtime operations such as
-// sends to unbuffered channels can write to arbitrary parts of the
-// stack, including above the lowest un-hit stack barrier. We solve
-// this in two ways. In many cases, the runtime can perform an
-// explicit write barrier operation like in case 2. However, in the
-// case of bulk memory move (typedmemmove), the runtime doesn't
-// necessary have ready access to a pointer bitmap for the memory
-// being copied, so it simply unwinds any stack barriers below the
-// destination.
-//
-// Gotchas
-// -------
-//
-// Anything that inspects or manipulates the stack potentially needs
-// to understand stack barriers. The most obvious case is that
-// gentraceback needs to use the original return PC when it encounters
-// the stack barrier trampoline. Anything that unwinds the stack such
-// as panic/recover must unwind stack barriers in tandem with
-// unwinding the stack.
-//
-// Stack barriers require that any goroutine whose stack has been
-// scanned must execute write barriers. Go solves this by simply
-// enabling write barriers globally during the concurrent scan phase.
-// However, traditionally, write barriers are not enabled during this
-// phase.
-//
-// Synchronization
-// ---------------
-//
-// For the most part, accessing and modifying stack barriers is
-// synchronized around GC safe points. Installing stack barriers
-// forces the G to a safe point, while all other operations that
-// modify stack barriers run on the G and prevent it from reaching a
-// safe point.
-//
-// Subtlety arises when a G may be tracebacked when *not* at a safe
-// point. This happens during sigprof. For this, each G has a "stack
-// barrier lock" (see gcLockStackBarriers, gcUnlockStackBarriers).
-// Operations that manipulate stack barriers acquire this lock, while
-// sigprof tries to acquire it and simply skips the traceback if it
-// can't acquire it. There is one exception for performance and
-// complexity reasons: hitting a stack barrier manipulates the stack
-// barrier list without acquiring the stack barrier lock. For this,
-// gentraceback performs a special fix up if the traceback starts in
-// the stack barrier function.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const debugStackBarrier = false
-
-// firstStackBarrierOffset is the approximate byte offset at
-// which to place the first stack barrier from the current SP.
-// This is a lower bound on how much stack will have to be
-// re-scanned during mark termination. Subsequent barriers are
-// placed at firstStackBarrierOffset * 2^n offsets.
-//
-// For debugging, this can be set to 0, which will install a
-// stack barrier at every frame. If you do this, you may also
-// have to raise _StackMin, since the stack barrier
-// bookkeeping will use a large amount of each stack.
-var firstStackBarrierOffset = 1024
-
-// gcMaxStackBarriers returns the maximum number of stack barriers
-// that can be installed in a stack of stackSize bytes.
-func gcMaxStackBarriers(stackSize int) (n int) {
-	if debug.gcstackbarrieroff > 0 {
-		return 0
-	}
-
-	if firstStackBarrierOffset == 0 {
-		// Special debugging case for inserting stack barriers
-		// at every frame. Steal half of the stack for the
-		// []stkbar. Technically, if the stack were to consist
-		// solely of return PCs we would need two thirds of
-		// the stack, but stealing that much breaks things and
-		// this doesn't happen in practice.
-		return stackSize / 2 / int(unsafe.Sizeof(stkbar{}))
-	}
-
-	offset := firstStackBarrierOffset
-	for offset < stackSize {
-		n++
-		offset *= 2
-	}
-	return n + 1
-}
-
-// gcInstallStackBarrier installs a stack barrier over the return PC of frame.
-//go:nowritebarrier
-func gcInstallStackBarrier(gp *g, frame *stkframe) bool {
-	if frame.lr == 0 {
-		if debugStackBarrier {
-			print("not installing stack barrier with no LR, goid=", gp.goid, "\n")
-		}
-		return false
-	}
-
-	if frame.fn.entry == cgocallback_gofuncPC {
-		// cgocallback_gofunc doesn't return to its LR;
-		// instead, its return path puts LR in g.sched.pc and
-		// switches back to the system stack on which
-		// cgocallback_gofunc was originally called. We can't
-		// have a stack barrier in g.sched.pc, so don't
-		// install one in this frame.
-		if debugStackBarrier {
-			print("not installing stack barrier over LR of cgocallback_gofunc, goid=", gp.goid, "\n")
-		}
-		return false
-	}
-
-	// Save the return PC and overwrite it with stackBarrier.
-	var lrUintptr uintptr
-	if usesLR {
-		lrUintptr = frame.sp
-	} else {
-		lrUintptr = frame.fp - sys.RegSize
-	}
-	lrPtr := (*sys.Uintreg)(unsafe.Pointer(lrUintptr))
-	if debugStackBarrier {
-		print("install stack barrier at ", hex(lrUintptr), " over ", hex(*lrPtr), ", goid=", gp.goid, "\n")
-		if uintptr(*lrPtr) != frame.lr {
-			print("frame.lr=", hex(frame.lr))
-			throw("frame.lr differs from stack LR")
-		}
-	}
-
-	gp.stkbar = gp.stkbar[:len(gp.stkbar)+1]
-	stkbar := &gp.stkbar[len(gp.stkbar)-1]
-	stkbar.savedLRPtr = lrUintptr
-	stkbar.savedLRVal = uintptr(*lrPtr)
-	*lrPtr = sys.Uintreg(stackBarrierPC)
-	return true
-}
-
-// gcRemoveStackBarriers removes all stack barriers installed in gp's stack.
-//
-// gp's stack barriers must be locked.
-//
-//go:nowritebarrier
-func gcRemoveStackBarriers(gp *g) {
-	if debugStackBarrier && gp.stkbarPos != 0 {
-		print("hit ", gp.stkbarPos, " stack barriers, goid=", gp.goid, "\n")
-	}
-
-	// Remove stack barriers that we didn't hit.
-	for _, stkbar := range gp.stkbar[gp.stkbarPos:] {
-		gcRemoveStackBarrier(gp, stkbar)
-	}
-
-	// Clear recorded stack barriers so copystack doesn't try to
-	// adjust them.
-	gp.stkbarPos = 0
-	gp.stkbar = gp.stkbar[:0]
-}
-
-// gcRemoveStackBarrier removes a single stack barrier. It is the
-// inverse operation of gcInstallStackBarrier.
-//
-// This is nosplit to ensure gp's stack does not move.
-//
-//go:nowritebarrier
-//go:nosplit
-func gcRemoveStackBarrier(gp *g, stkbar stkbar) {
-	if debugStackBarrier {
-		print("remove stack barrier at ", hex(stkbar.savedLRPtr), " with ", hex(stkbar.savedLRVal), ", goid=", gp.goid, "\n")
-	}
-	lrPtr := (*sys.Uintreg)(unsafe.Pointer(stkbar.savedLRPtr))
-	if val := *lrPtr; val != sys.Uintreg(stackBarrierPC) {
-		printlock()
-		print("at *", hex(stkbar.savedLRPtr), " expected stack barrier PC ", hex(stackBarrierPC), ", found ", hex(val), ", goid=", gp.goid, "\n")
-		print("gp.stkbar=")
-		gcPrintStkbars(gp, -1)
-		print(", gp.stack=[", hex(gp.stack.lo), ",", hex(gp.stack.hi), ")\n")
-		throw("stack barrier lost")
-	}
-	*lrPtr = sys.Uintreg(stkbar.savedLRVal)
-}
-
-// gcTryRemoveAllStackBarriers tries to remove stack barriers from all
-// Gs in gps. It is best-effort and efficient. If it can't remove
-// barriers from a G immediately, it will simply skip it.
-func gcTryRemoveAllStackBarriers(gps []*g) {
-	for _, gp := range gps {
-	retry:
-		for {
-			switch s := readgstatus(gp); s {
-			default:
-				break retry
-
-			case _Grunnable, _Gsyscall, _Gwaiting:
-				if !castogscanstatus(gp, s, s|_Gscan) {
-					continue
-				}
-				gcLockStackBarriers(gp)
-				gcRemoveStackBarriers(gp)
-				gcUnlockStackBarriers(gp)
-				restartg(gp)
-				break retry
-			}
-		}
-	}
-}
-
-// gcPrintStkbars prints the stack barriers of gp for debugging. It
-// places a "@@@" marker at gp.stkbarPos. If marker >= 0, it will also
-// place a "==>" marker before the marker'th entry.
-func gcPrintStkbars(gp *g, marker int) {
-	print("[")
-	for i, s := range gp.stkbar {
-		if i > 0 {
-			print(" ")
-		}
-		if i == int(gp.stkbarPos) {
-			print("@@@ ")
-		}
-		if i == marker {
-			print("==> ")
-		}
-		print("*", hex(s.savedLRPtr), "=", hex(s.savedLRVal))
-	}
-	if int(gp.stkbarPos) == len(gp.stkbar) {
-		print(" @@@")
-	}
-	if marker == len(gp.stkbar) {
-		print(" ==>")
-	}
-	print("]")
-}
-
-// gcUnwindBarriers marks all stack barriers up the frame containing
-// sp as hit and removes them. This is used during stack unwinding for
-// panic/recover and by heapBitsBulkBarrier to force stack re-scanning
-// when its destination is on the stack.
-//
-// This is nosplit to ensure gp's stack does not move.
-//
-//go:nosplit
-func gcUnwindBarriers(gp *g, sp uintptr) {
-	gcLockStackBarriers(gp)
-	// On LR machines, if there is a stack barrier on the return
-	// from the frame containing sp, this will mark it as hit even
-	// though it isn't, but it's okay to be conservative.
-	before := gp.stkbarPos
-	for int(gp.stkbarPos) < len(gp.stkbar) && gp.stkbar[gp.stkbarPos].savedLRPtr < sp {
-		gcRemoveStackBarrier(gp, gp.stkbar[gp.stkbarPos])
-		gp.stkbarPos++
-	}
-	gcUnlockStackBarriers(gp)
-	if debugStackBarrier && gp.stkbarPos != before {
-		print("skip barriers below ", hex(sp), " in goid=", gp.goid, ": ")
-		// We skipped barriers between the "==>" marker
-		// (before) and the "@@@" marker (gp.stkbarPos).
-		gcPrintStkbars(gp, int(before))
-		print("\n")
-	}
-}
-
-// nextBarrierPC returns the original return PC of the next stack barrier.
-// Used by getcallerpc, so it must be nosplit.
-//go:nosplit
-func nextBarrierPC() uintptr {
-	gp := getg()
-	return gp.stkbar[gp.stkbarPos].savedLRVal
-}
-
-// setNextBarrierPC sets the return PC of the next stack barrier.
-// Used by setcallerpc, so it must be nosplit.
-//go:nosplit
-func setNextBarrierPC(pc uintptr) {
-	gp := getg()
-	gcLockStackBarriers(gp)
-	gp.stkbar[gp.stkbarPos].savedLRVal = pc
-	gcUnlockStackBarriers(gp)
-}
-
-// gcLockStackBarriers synchronizes with tracebacks of gp's stack
-// during sigprof for installation or removal of stack barriers. It
-// blocks until any current sigprof is done tracebacking gp's stack
-// and then disallows profiling tracebacks of gp's stack.
-//
-// This is necessary because a sigprof during barrier installation or
-// removal could observe inconsistencies between the stkbar array and
-// the stack itself and crash.
-//
-//go:nosplit
-func gcLockStackBarriers(gp *g) {
-	// Disable preemption so scanstack cannot run while the caller
-	// is manipulating the stack barriers.
-	acquirem()
-	for !atomic.Cas(&gp.stackLock, 0, 1) {
-		osyield()
-	}
-}
-
-//go:nosplit
-func gcTryLockStackBarriers(gp *g) bool {
-	mp := acquirem()
-	result := atomic.Cas(&gp.stackLock, 0, 1)
-	if !result {
-		releasem(mp)
-	}
-	return result
-}
-
-func gcUnlockStackBarriers(gp *g) {
-	atomic.Store(&gp.stackLock, 0)
-	releasem(getg().m)
-}
diff --git a/libgo/go/runtime/net_plan9.go b/libgo/go/runtime/net_plan9.go
index 10fd089..77ae8c6 100644
--- a/libgo/go/runtime/net_plan9.go
+++ b/libgo/go/runtime/net_plan9.go
@@ -8,12 +8,12 @@
 	_ "unsafe"
 )
 
-//go:linkname runtime_ignoreHangup net.runtime_ignoreHangup
+//go:linkname runtime_ignoreHangup internal_poll.runtime_ignoreHangup
 func runtime_ignoreHangup() {
 	getg().m.ignoreHangup = true
 }
 
-//go:linkname runtime_unignoreHangup net.runtime_unignoreHangup
+//go:linkname runtime_unignoreHangup internal_poll.runtime_unignoreHangup
 func runtime_unignoreHangup(sig string) {
 	getg().m.ignoreHangup = false
 }
diff --git a/libgo/go/runtime/netpoll.go b/libgo/go/runtime/netpoll.go
index 8932455..e9bbfec 100644
--- a/libgo/go/runtime/netpoll.go
+++ b/libgo/go/runtime/netpoll.go
@@ -80,12 +80,13 @@
 }
 
 var (
-	netpollInited uint32
-	pollcache     pollCache
+	netpollInited  uint32
+	pollcache      pollCache
+	netpollWaiters uint32
 )
 
-//go:linkname net_runtime_pollServerInit net.runtime_pollServerInit
-func net_runtime_pollServerInit() {
+//go:linkname poll_runtime_pollServerInit internal_poll.runtime_pollServerInit
+func poll_runtime_pollServerInit() {
 	netpollinit()
 	atomic.Store(&netpollInited, 1)
 }
@@ -94,15 +95,23 @@
 	return atomic.Load(&netpollInited) != 0
 }
 
-//go:linkname net_runtime_pollOpen net.runtime_pollOpen
-func net_runtime_pollOpen(fd uintptr) (*pollDesc, int) {
+//go:linkname poll_runtime_pollServerDescriptor internal_poll.runtime_pollServerDescriptor
+
+// poll_runtime_pollServerDescriptor returns the descriptor being used,
+// or ^uintptr(0) if the system does not use a poll descriptor.
+func poll_runtime_pollServerDescriptor() uintptr {
+	return netpolldescriptor()
+}
+
+//go:linkname poll_runtime_pollOpen internal_poll.runtime_pollOpen
+func poll_runtime_pollOpen(fd uintptr) (*pollDesc, int) {
 	pd := pollcache.alloc()
 	lock(&pd.lock)
 	if pd.wg != 0 && pd.wg != pdReady {
-		throw("netpollOpen: blocked write on free descriptor")
+		throw("runtime: blocked write on free polldesc")
 	}
 	if pd.rg != 0 && pd.rg != pdReady {
-		throw("netpollOpen: blocked read on free descriptor")
+		throw("runtime: blocked read on free polldesc")
 	}
 	pd.fd = fd
 	pd.closing = false
@@ -118,16 +127,16 @@
 	return pd, int(errno)
 }
 
-//go:linkname net_runtime_pollClose net.runtime_pollClose
-func net_runtime_pollClose(pd *pollDesc) {
+//go:linkname poll_runtime_pollClose internal_poll.runtime_pollClose
+func poll_runtime_pollClose(pd *pollDesc) {
 	if !pd.closing {
-		throw("netpollClose: close w/o unblock")
+		throw("runtime: close polldesc w/o unblock")
 	}
 	if pd.wg != 0 && pd.wg != pdReady {
-		throw("netpollClose: blocked write on closing descriptor")
+		throw("runtime: blocked write on closing polldesc")
 	}
 	if pd.rg != 0 && pd.rg != pdReady {
-		throw("netpollClose: blocked read on closing descriptor")
+		throw("runtime: blocked read on closing polldesc")
 	}
 	netpollclose(pd.fd)
 	pollcache.free(pd)
@@ -140,8 +149,8 @@
 	unlock(&c.lock)
 }
 
-//go:linkname net_runtime_pollReset net.runtime_pollReset
-func net_runtime_pollReset(pd *pollDesc, mode int) int {
+//go:linkname poll_runtime_pollReset internal_poll.runtime_pollReset
+func poll_runtime_pollReset(pd *pollDesc, mode int) int {
 	err := netpollcheckerr(pd, int32(mode))
 	if err != 0 {
 		return err
@@ -154,8 +163,8 @@
 	return 0
 }
 
-//go:linkname net_runtime_pollWait net.runtime_pollWait
-func net_runtime_pollWait(pd *pollDesc, mode int) int {
+//go:linkname poll_runtime_pollWait internal_poll.runtime_pollWait
+func poll_runtime_pollWait(pd *pollDesc, mode int) int {
 	err := netpollcheckerr(pd, int32(mode))
 	if err != 0 {
 		return err
@@ -176,16 +185,16 @@
 	return 0
 }
 
-//go:linkname net_runtime_pollWaitCanceled net.runtime_pollWaitCanceled
-func net_runtime_pollWaitCanceled(pd *pollDesc, mode int) {
+//go:linkname poll_runtime_pollWaitCanceled internal_poll.runtime_pollWaitCanceled
+func poll_runtime_pollWaitCanceled(pd *pollDesc, mode int) {
 	// This function is used only on windows after a failed attempt to cancel
 	// a pending async IO operation. Wait for ioready, ignore closing or timeouts.
 	for !netpollblock(pd, int32(mode), true) {
 	}
 }
 
-//go:linkname net_runtime_pollSetDeadline net.runtime_pollSetDeadline
-func net_runtime_pollSetDeadline(pd *pollDesc, d int64, mode int) {
+//go:linkname poll_runtime_pollSetDeadline internal_poll.runtime_pollSetDeadline
+func poll_runtime_pollSetDeadline(pd *pollDesc, d int64, mode int) {
 	lock(&pd.lock)
 	if pd.closing {
 		unlock(&pd.lock)
@@ -247,18 +256,18 @@
 	}
 	unlock(&pd.lock)
 	if rg != nil {
-		goready(rg, 3)
+		netpollgoready(rg, 3)
 	}
 	if wg != nil {
-		goready(wg, 3)
+		netpollgoready(wg, 3)
 	}
 }
 
-//go:linkname net_runtime_pollUnblock net.runtime_pollUnblock
-func net_runtime_pollUnblock(pd *pollDesc) {
+//go:linkname poll_runtime_pollUnblock internal_poll.runtime_pollUnblock
+func poll_runtime_pollUnblock(pd *pollDesc) {
 	lock(&pd.lock)
 	if pd.closing {
-		throw("netpollUnblock: already closing")
+		throw("runtime: unblock on closing polldesc")
 	}
 	pd.closing = true
 	pd.seq++
@@ -276,10 +285,10 @@
 	}
 	unlock(&pd.lock)
 	if rg != nil {
-		goready(rg, 3)
+		netpollgoready(rg, 3)
 	}
 	if wg != nil {
-		goready(wg, 3)
+		netpollgoready(wg, 3)
 	}
 }
 
@@ -315,7 +324,19 @@
 }
 
 func netpollblockcommit(gp *g, gpp unsafe.Pointer) bool {
-	return atomic.Casuintptr((*uintptr)(gpp), pdWait, uintptr(unsafe.Pointer(gp)))
+	r := atomic.Casuintptr((*uintptr)(gpp), pdWait, uintptr(unsafe.Pointer(gp)))
+	if r {
+		// Bump the count of goroutines waiting for the poller.
+		// The scheduler uses this to decide whether to block
+		// waiting for the poller if there is nothing else to do.
+		atomic.Xadd(&netpollWaiters, 1)
+	}
+	return r
+}
+
+func netpollgoready(gp *g, traceskip int) {
+	atomic.Xadd(&netpollWaiters, -1)
+	goready(gp, traceskip+1)
 }
 
 // returns true if IO is ready, or false if timedout or closed
@@ -334,7 +355,7 @@
 			return true
 		}
 		if old != 0 {
-			throw("netpollblock: double wait")
+			throw("runtime: double wait")
 		}
 		if atomic.Casuintptr(gpp, 0, pdWait) {
 			break
@@ -350,7 +371,7 @@
 	// be careful to not lose concurrent READY notification
 	old := atomic.Xchguintptr(gpp, 0)
 	if old > pdWait {
-		throw("netpollblock: corrupted state")
+		throw("runtime: corrupted polldesc")
 	}
 	return old == pdReady
 }
@@ -396,7 +417,7 @@
 	var rg *g
 	if read {
 		if pd.rd <= 0 || pd.rt.f == nil {
-			throw("netpolldeadlineimpl: inconsistent read deadline")
+			throw("runtime: inconsistent read deadline")
 		}
 		pd.rd = -1
 		atomicstorep(unsafe.Pointer(&pd.rt.f), nil) // full memory barrier between store to rd and load of rg in netpollunblock
@@ -405,7 +426,7 @@
 	var wg *g
 	if write {
 		if pd.wd <= 0 || pd.wt.f == nil && !read {
-			throw("netpolldeadlineimpl: inconsistent write deadline")
+			throw("runtime: inconsistent write deadline")
 		}
 		pd.wd = -1
 		atomicstorep(unsafe.Pointer(&pd.wt.f), nil) // full memory barrier between store to wd and load of wg in netpollunblock
@@ -413,10 +434,10 @@
 	}
 	unlock(&pd.lock)
 	if rg != nil {
-		goready(rg, 0)
+		netpollgoready(rg, 0)
 	}
 	if wg != nil {
-		goready(wg, 0)
+		netpollgoready(wg, 0)
 	}
 }
 
diff --git a/libgo/go/runtime/netpoll_epoll.go b/libgo/go/runtime/netpoll_epoll.go
index 247692e..ced399d 100644
--- a/libgo/go/runtime/netpoll_epoll.go
+++ b/libgo/go/runtime/netpoll_epoll.go
@@ -47,6 +47,10 @@
 	throw("netpollinit: failed to create descriptor")
 }
 
+func netpolldescriptor() uintptr {
+	return uintptr(epfd)
+}
+
 func netpollopen(fd uintptr, pd *pollDesc) int32 {
 	var ev epollevent
 	ev.events = _EPOLLIN | _EPOLLOUT | _EPOLLRDHUP | _EPOLLETpos
@@ -66,7 +70,7 @@
 }
 
 func netpollarm(pd *pollDesc, mode int) {
-	throw("unused")
+	throw("runtime: unused")
 }
 
 // polls for ready network connections
@@ -86,7 +90,7 @@
 		e := errno()
 		if e != _EINTR {
 			println("runtime: epollwait on fd", epfd, "failed with", e)
-			throw("epollwait failed")
+			throw("runtime: netpoll failed")
 		}
 		goto retry
 	}
diff --git a/libgo/go/runtime/netpoll_kqueue.go b/libgo/go/runtime/netpoll_kqueue.go
index eae4f21..47927fe 100644
--- a/libgo/go/runtime/netpoll_kqueue.go
+++ b/libgo/go/runtime/netpoll_kqueue.go
@@ -32,11 +32,15 @@
 	kq = kqueue()
 	if kq < 0 {
 		println("netpollinit: kqueue failed with", errno())
-		throw("netpollinit: kqueue failed")
+		throw("runtime: netpollinit failed")
 	}
 	closeonexec(kq)
 }
 
+func netpolldescriptor() uintptr {
+	return uintptr(kq)
+}
+
 func netpollopen(fd uintptr, pd *pollDesc) int32 {
 	// Arm both EVFILT_READ and EVFILT_WRITE in edge-triggered mode (EV_CLEAR)
 	// for the whole fd lifetime. The notifications are automatically unregistered
@@ -64,7 +68,7 @@
 }
 
 func netpollarm(pd *pollDesc, mode int) {
-	throw("unused")
+	throw("runtime: unused")
 }
 
 // Polls for ready network connections.
@@ -85,7 +89,7 @@
 		e := errno()
 		if e != _EINTR {
 			println("runtime: kevent on fd", kq, "failed with", e)
-			throw("kevent failed")
+			throw("runtime: netpoll failed")
 		}
 		goto retry
 	}
diff --git a/libgo/go/runtime/netpoll_nacl.go b/libgo/go/runtime/netpoll_nacl.go
index 5cbc300..dc5a55e 100644
--- a/libgo/go/runtime/netpoll_nacl.go
+++ b/libgo/go/runtime/netpoll_nacl.go
@@ -10,6 +10,10 @@
 func netpollinit() {
 }
 
+func netpolldescriptor() uintptr {
+	return ^uintptr(0)
+}
+
 func netpollopen(fd uintptr, pd *pollDesc) int32 {
 	return 0
 }
diff --git a/libgo/go/runtime/netpoll_solaris.go b/libgo/go/runtime/netpoll_solaris.go
index cc6754c..e1e7385 100644
--- a/libgo/go/runtime/netpoll_solaris.go
+++ b/libgo/go/runtime/netpoll_solaris.go
@@ -96,8 +96,12 @@
 		return
 	}
 
-	print("netpollinit: failed to create port (", errno(), ")\n")
-	throw("netpollinit: failed to create port")
+	print("runtime: port_create failed (errno=", errno(), ")\n")
+	throw("runtime: netpollinit failed")
+}
+
+func netpolldescriptor() uintptr {
+	return uintptr(portfd)
 }
 
 func netpollopen(fd uintptr, pd *pollDesc) int32 {
@@ -139,8 +143,8 @@
 	}
 
 	if events != 0 && port_associate(portfd, _PORT_SOURCE_FD, pd.fd, events, uintptr(unsafe.Pointer(pd))) != 0 {
-		print("netpollupdate: failed to associate (", errno(), ")\n")
-		throw("netpollupdate: failed to associate")
+		print("runtime: port_associate failed (errno=", errno(), ")\n")
+		throw("runtime: netpollupdate failed")
 	}
 	pd.user = events
 }
@@ -154,7 +158,7 @@
 	case 'w':
 		netpollupdate(pd, _POLLOUT, 0)
 	default:
-		throw("netpollarm: bad mode")
+		throw("runtime: bad mode")
 	}
 	unlock(&pd.lock)
 }
@@ -177,8 +181,8 @@
 	var n uint32 = 1
 	if port_getn(portfd, &events[0], uint32(len(events)), &n, wait) < 0 {
 		if e := errno(); e != _EINTR {
-			print("runtime: port_getn on fd ", portfd, " failed with ", e, "\n")
-			throw("port_getn failed")
+			print("runtime: port_getn on fd ", portfd, " failed (errno=", e, ")\n")
+			throw("runtime: netpoll failed")
 		}
 		goto retry
 	}
diff --git a/libgo/go/runtime/netpoll_stub.go b/libgo/go/runtime/netpoll_stub.go
index 09f64ad..a4d6b46 100644
--- a/libgo/go/runtime/netpoll_stub.go
+++ b/libgo/go/runtime/netpoll_stub.go
@@ -6,6 +6,8 @@
 
 package runtime
 
+var netpollWaiters uint32
+
 // Polls for ready network connections.
 // Returns list of goroutines that become runnable.
 func netpoll(block bool) (gp *g) {
diff --git a/libgo/go/runtime/netpoll_windows.go b/libgo/go/runtime/netpoll_windows.go
index 7ad1158..79dafb0 100644
--- a/libgo/go/runtime/netpoll_windows.go
+++ b/libgo/go/runtime/netpoll_windows.go
@@ -12,7 +12,8 @@
 
 const _INVALID_HANDLE_VALUE = ^uintptr(0)
 
-// net_op must be the same as beginning of net.operation. Keep these in sync.
+// net_op must be the same as beginning of internal/poll.operation.
+// Keep these in sync.
 type net_op struct {
 	// used by windows
 	o overlapped
@@ -35,11 +36,15 @@
 func netpollinit() {
 	iocphandle = stdcall4(_CreateIoCompletionPort, _INVALID_HANDLE_VALUE, 0, 0, _DWORD_MAX)
 	if iocphandle == 0 {
-		println("netpoll: failed to create iocp handle (errno=", getlasterror(), ")")
-		throw("netpoll: failed to create iocp handle")
+		println("runtime: CreateIoCompletionPort failed (errno=", getlasterror(), ")")
+		throw("runtime: netpollinit failed")
 	}
 }
 
+func netpolldescriptor() uintptr {
+	return iocphandle
+}
+
 func netpollopen(fd uintptr, pd *pollDesc) int32 {
 	if stdcall4(_CreateIoCompletionPort, fd, iocphandle, 0, 0) == 0 {
 		return -int32(getlasterror())
@@ -53,7 +58,7 @@
 }
 
 func netpollarm(pd *pollDesc, mode int) {
-	throw("unused")
+	throw("runtime: unused")
 }
 
 // Polls for completed network IO.
@@ -89,8 +94,8 @@
 			if !block && errno == _WAIT_TIMEOUT {
 				return nil
 			}
-			println("netpoll: GetQueuedCompletionStatusEx failed (errno=", errno, ")")
-			throw("netpoll: GetQueuedCompletionStatusEx failed")
+			println("runtime: GetQueuedCompletionStatusEx failed (errno=", errno, ")")
+			throw("runtime: netpoll failed")
 		}
 		mp.blocked = false
 		for i = 0; i < n; i++ {
@@ -116,8 +121,8 @@
 				return nil
 			}
 			if op == nil {
-				println("netpoll: GetQueuedCompletionStatus failed (errno=", errno, ")")
-				throw("netpoll: GetQueuedCompletionStatus failed")
+				println("runtime: GetQueuedCompletionStatus failed (errno=", errno, ")")
+				throw("runtime: netpoll failed")
 			}
 			// dequeued failed IO packet, so report that
 		}
@@ -132,12 +137,13 @@
 
 func handlecompletion(gpp *guintptr, op *net_op, errno int32, qty uint32) {
 	if op == nil {
-		throw("netpoll: GetQueuedCompletionStatus returned op == nil")
+		println("runtime: GetQueuedCompletionStatus returned op == nil")
+		throw("runtime: netpoll failed")
 	}
 	mode := op.mode
 	if mode != 'r' && mode != 'w' {
-		println("netpoll: GetQueuedCompletionStatus returned invalid mode=", mode)
-		throw("netpoll: GetQueuedCompletionStatus returned invalid mode")
+		println("runtime: GetQueuedCompletionStatus returned invalid mode=", mode)
+		throw("runtime: netpoll failed")
 	}
 	op.errno = errno
 	op.qty = qty
diff --git a/libgo/go/runtime/numcpu_freebsd_test.go b/libgo/go/runtime/numcpu_freebsd_test.go
new file mode 100644
index 0000000..e78890a
--- /dev/null
+++ b/libgo/go/runtime/numcpu_freebsd_test.go
@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime_test
+
+import "testing"
+
+func TestFreeBSDNumCPU(t *testing.T) {
+	got := runTestProg(t, "testprog", "FreeBSDNumCPU")
+	want := "OK\n"
+	if got != want {
+		t.Fatalf("expected %q, but got:\n%s", want, got)
+	}
+}
diff --git a/libgo/go/runtime/os_gccgo.go b/libgo/go/runtime/os_gccgo.go
index db3ea48..5709555 100644
--- a/libgo/go/runtime/os_gccgo.go
+++ b/libgo/go/runtime/os_gccgo.go
@@ -8,7 +8,7 @@
 	"unsafe"
 )
 
-// Temporary for C code to call:
+// For C code to call:
 //go:linkname minit runtime.minit
 
 func goenvs() {
diff --git a/libgo/go/runtime/panic.go b/libgo/go/runtime/panic.go
index 43d595f..2f65603 100644
--- a/libgo/go/runtime/panic.go
+++ b/libgo/go/runtime/panic.go
@@ -450,6 +450,8 @@
 	}
 	gp._panic = p
 
+	atomic.Xadd(&runningPanicDefers, 1)
+
 	for {
 		d := gp._defer
 		if d == nil {
@@ -486,8 +488,8 @@
 		d._panic = nil
 
 		if p.recovered {
-			// Some deferred function called recover.
-			// Stop running this panic.
+			atomic.Xadd(&runningPanicDefers, -1)
+
 			gp._panic = p.link
 
 			// Aborted panics are marked but remain on the g.panic list.
@@ -531,6 +533,11 @@
 	// and String methods to prepare the panic strings before startpanic.
 	preprintpanics(gp._panic)
 	startpanic()
+
+	// startpanic set panicking, which will block main from exiting,
+	// so now OK to decrement runningPanicDefers.
+	atomic.Xadd(&runningPanicDefers, -1)
+
 	printpanics(gp._panic)
 	dopanic(0)       // should not return
 	*(*int)(nil) = 0 // not reached
@@ -801,7 +808,17 @@
 	*(*int)(nil) = 0 // not reached
 }
 
-//uint32 runtime·panicking;
+// runningPanicDefers is non-zero while running deferred functions for panic.
+// runningPanicDefers is incremented and decremented atomically.
+// This is used to try hard to get a panic stack trace out when exiting.
+var runningPanicDefers uint32
+
+// panicking is non-zero when crashing the program for an unrecovered panic.
+// panicking is incremented and decremented atomically.
+var panicking uint32
+
+// paniclk is held while printing the panic information and stack trace,
+// so that two concurrent panics don't overlap their output.
 var paniclk mutex
 
 func startpanic() {
diff --git a/libgo/go/runtime/pprof/elf.go b/libgo/go/runtime/pprof/elf.go
new file mode 100644
index 0000000..a8b5ea6
--- /dev/null
+++ b/libgo/go/runtime/pprof/elf.go
@@ -0,0 +1,109 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"os"
+)
+
+var (
+	errBadELF    = errors.New("malformed ELF binary")
+	errNoBuildID = errors.New("no NT_GNU_BUILD_ID found in ELF binary")
+)
+
+// elfBuildID returns the GNU build ID of the named ELF binary,
+// without introducing a dependency on debug/elf and its dependencies.
+func elfBuildID(file string) (string, error) {
+	buf := make([]byte, 256)
+	f, err := os.Open(file)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	if _, err := f.ReadAt(buf[:64], 0); err != nil {
+		return "", err
+	}
+
+	// ELF file begins with \x7F E L F.
+	if buf[0] != 0x7F || buf[1] != 'E' || buf[2] != 'L' || buf[3] != 'F' {
+		return "", errBadELF
+	}
+
+	var byteOrder binary.ByteOrder
+	switch buf[5] {
+	default:
+		return "", errBadELF
+	case 1: // little-endian
+		byteOrder = binary.LittleEndian
+	case 2: // big-endian
+		byteOrder = binary.BigEndian
+	}
+
+	var shnum int
+	var shoff, shentsize int64
+	switch buf[4] {
+	default:
+		return "", errBadELF
+	case 1: // 32-bit file header
+		shoff = int64(byteOrder.Uint32(buf[32:]))
+		shentsize = int64(byteOrder.Uint16(buf[46:]))
+		if shentsize != 40 {
+			return "", errBadELF
+		}
+		shnum = int(byteOrder.Uint16(buf[48:]))
+	case 2: // 64-bit file header
+		shoff = int64(byteOrder.Uint64(buf[40:]))
+		shentsize = int64(byteOrder.Uint16(buf[58:]))
+		if shentsize != 64 {
+			return "", errBadELF
+		}
+		shnum = int(byteOrder.Uint16(buf[60:]))
+	}
+
+	for i := 0; i < shnum; i++ {
+		if _, err := f.ReadAt(buf[:shentsize], shoff+int64(i)*shentsize); err != nil {
+			return "", err
+		}
+		if typ := byteOrder.Uint32(buf[4:]); typ != 7 { // SHT_NOTE
+			continue
+		}
+		var off, size int64
+		if shentsize == 40 {
+			// 32-bit section header
+			off = int64(byteOrder.Uint32(buf[16:]))
+			size = int64(byteOrder.Uint32(buf[20:]))
+		} else {
+			// 64-bit section header
+			off = int64(byteOrder.Uint64(buf[24:]))
+			size = int64(byteOrder.Uint64(buf[32:]))
+		}
+		size += off
+		for off < size {
+			if _, err := f.ReadAt(buf[:16], off); err != nil { // room for header + name GNU\x00
+				return "", err
+			}
+			nameSize := int(byteOrder.Uint32(buf[0:]))
+			descSize := int(byteOrder.Uint32(buf[4:]))
+			noteType := int(byteOrder.Uint32(buf[8:]))
+			descOff := off + int64(12+(nameSize+3)&^3)
+			off = descOff + int64((descSize+3)&^3)
+			if nameSize != 4 || noteType != 3 || buf[12] != 'G' || buf[13] != 'N' || buf[14] != 'U' || buf[15] != '\x00' { // want name GNU\x00 type 3 (NT_GNU_BUILD_ID)
+				continue
+			}
+			if descSize > len(buf) {
+				return "", errBadELF
+			}
+			if _, err := f.ReadAt(buf[:descSize], descOff); err != nil {
+				return "", err
+			}
+			return fmt.Sprintf("%x", buf[:descSize]), nil
+		}
+	}
+	return "", errNoBuildID
+}
diff --git a/libgo/go/internal/pprof/profile/encode.go b/libgo/go/runtime/pprof/internal/profile/encode.go
similarity index 100%
rename from libgo/go/internal/pprof/profile/encode.go
rename to libgo/go/runtime/pprof/internal/profile/encode.go
diff --git a/libgo/go/internal/pprof/profile/filter.go b/libgo/go/runtime/pprof/internal/profile/filter.go
similarity index 100%
rename from libgo/go/internal/pprof/profile/filter.go
rename to libgo/go/runtime/pprof/internal/profile/filter.go
diff --git a/libgo/go/internal/pprof/profile/legacy_profile.go b/libgo/go/runtime/pprof/internal/profile/legacy_profile.go
similarity index 100%
rename from libgo/go/internal/pprof/profile/legacy_profile.go
rename to libgo/go/runtime/pprof/internal/profile/legacy_profile.go
diff --git a/libgo/go/internal/pprof/profile/profile.go b/libgo/go/runtime/pprof/internal/profile/profile.go
similarity index 98%
rename from libgo/go/internal/pprof/profile/profile.go
rename to libgo/go/runtime/pprof/internal/profile/profile.go
index 28e713d..9b6a6f9 100644
--- a/libgo/go/internal/pprof/profile/profile.go
+++ b/libgo/go/runtime/pprof/internal/profile/profile.go
@@ -4,6 +4,9 @@
 
 // Package profile provides a representation of profile.proto and
 // methods to encode/decode profiles in this format.
+//
+// This package is only for testing runtime/pprof.
+// It is not used by production Go programs.
 package profile
 
 import (
diff --git a/libgo/go/internal/pprof/profile/profile_test.go b/libgo/go/runtime/pprof/internal/profile/profile_test.go
similarity index 100%
rename from libgo/go/internal/pprof/profile/profile_test.go
rename to libgo/go/runtime/pprof/internal/profile/profile_test.go
diff --git a/libgo/go/internal/pprof/profile/proto.go b/libgo/go/runtime/pprof/internal/profile/proto.go
similarity index 100%
rename from libgo/go/internal/pprof/profile/proto.go
rename to libgo/go/runtime/pprof/internal/profile/proto.go
diff --git a/libgo/go/internal/pprof/profile/proto_test.go b/libgo/go/runtime/pprof/internal/profile/proto_test.go
similarity index 100%
rename from libgo/go/internal/pprof/profile/proto_test.go
rename to libgo/go/runtime/pprof/internal/profile/proto_test.go
diff --git a/libgo/go/internal/pprof/profile/prune.go b/libgo/go/runtime/pprof/internal/profile/prune.go
similarity index 100%
rename from libgo/go/internal/pprof/profile/prune.go
rename to libgo/go/runtime/pprof/internal/profile/prune.go
diff --git a/libgo/go/runtime/pprof/internal/protopprof/protomemprofile.go b/libgo/go/runtime/pprof/internal/protopprof/protomemprofile.go
deleted file mode 100644
index c2ab5b5..0000000
--- a/libgo/go/runtime/pprof/internal/protopprof/protomemprofile.go
+++ /dev/null
@@ -1,83 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package protopprof
-
-import (
-	"internal/pprof/profile"
-	"math"
-	"runtime"
-	"time"
-)
-
-// EncodeMemProfile converts MemProfileRecords to a Profile.
-func EncodeMemProfile(mr []runtime.MemProfileRecord, rate int64, t time.Time) *profile.Profile {
-	p := &profile.Profile{
-		Period:     rate,
-		PeriodType: &profile.ValueType{Type: "space", Unit: "bytes"},
-		SampleType: []*profile.ValueType{
-			{Type: "alloc_objects", Unit: "count"},
-			{Type: "alloc_space", Unit: "bytes"},
-			{Type: "inuse_objects", Unit: "count"},
-			{Type: "inuse_space", Unit: "bytes"},
-		},
-		TimeNanos: int64(t.UnixNano()),
-	}
-
-	locs := make(map[uintptr]*profile.Location)
-	for _, r := range mr {
-		stack := r.Stack()
-		sloc := make([]*profile.Location, len(stack))
-		for i, addr := range stack {
-			loc := locs[addr]
-			if loc == nil {
-				loc = &profile.Location{
-					ID:      uint64(len(p.Location) + 1),
-					Address: uint64(addr),
-				}
-				locs[addr] = loc
-				p.Location = append(p.Location, loc)
-			}
-			sloc[i] = loc
-		}
-
-		ao, ab := scaleHeapSample(r.AllocObjects, r.AllocBytes, rate)
-		uo, ub := scaleHeapSample(r.InUseObjects(), r.InUseBytes(), rate)
-
-		p.Sample = append(p.Sample, &profile.Sample{
-			Value:    []int64{ao, ab, uo, ub},
-			Location: sloc,
-		})
-	}
-	if runtime.GOOS == "linux" {
-		addMappings(p)
-	}
-	return p
-}
-
-// scaleHeapSample adjusts the data from a heap Sample to
-// account for its probability of appearing in the collected
-// data. heap profiles are a sampling of the memory allocations
-// requests in a program. We estimate the unsampled value by dividing
-// each collected sample by its probability of appearing in the
-// profile. heap profiles rely on a poisson process to determine
-// which samples to collect, based on the desired average collection
-// rate R. The probability of a sample of size S to appear in that
-// profile is 1-exp(-S/R).
-func scaleHeapSample(count, size, rate int64) (int64, int64) {
-	if count == 0 || size == 0 {
-		return 0, 0
-	}
-
-	if rate <= 1 {
-		// if rate==1 all samples were collected so no adjustment is needed.
-		// if rate<1 treat as unknown and skip scaling.
-		return count, size
-	}
-
-	avgSize := float64(size) / float64(count)
-	scale := 1 / (1 - math.Exp(-avgSize/float64(rate)))
-
-	return int64(float64(count) * scale), int64(float64(size) * scale)
-}
diff --git a/libgo/go/runtime/pprof/internal/protopprof/protomemprofile_test.go b/libgo/go/runtime/pprof/internal/protopprof/protomemprofile_test.go
deleted file mode 100644
index a10fe77..0000000
--- a/libgo/go/runtime/pprof/internal/protopprof/protomemprofile_test.go
+++ /dev/null
@@ -1,104 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package protopprof
-
-import (
-	"bytes"
-	"internal/pprof/profile"
-	"io/ioutil"
-	"reflect"
-	"runtime"
-	"testing"
-	"time"
-)
-
-// TestSampledHeapAllocProfile tests encoding of a memory profile from
-// runtime.MemProfileRecord data.
-func TestSampledHeapAllocProfile(t *testing.T) {
-	if runtime.GOOS != "linux" {
-		t.Skip("Test requires a system with /proc/self/maps")
-	}
-
-	// Figure out two addresses from /proc/self/maps.
-	mmap, err := ioutil.ReadFile("/proc/self/maps")
-	if err != nil {
-		t.Fatal("Cannot read /proc/self/maps")
-	}
-	rd := bytes.NewReader(mmap)
-	mprof := &profile.Profile{}
-	if err = mprof.ParseMemoryMap(rd); err != nil {
-		t.Fatalf("Cannot parse /proc/self/maps")
-	}
-	if len(mprof.Mapping) < 2 {
-		// It is possible for a binary to only have 1 executable
-		// region of memory.
-		t.Skipf("need 2 or more mappings, got %v", len(mprof.Mapping))
-	}
-	address1 := mprof.Mapping[0].Start
-	address2 := mprof.Mapping[1].Start
-
-	var buf bytes.Buffer
-
-	rec, rate := testMemRecords(address1, address2)
-	p := EncodeMemProfile(rec, rate, time.Now())
-	if err := p.Write(&buf); err != nil {
-		t.Fatalf("Failed to write profile: %v", err)
-	}
-
-	p, err = profile.Parse(&buf)
-	if err != nil {
-		t.Fatalf("Could not parse Profile profile: %v", err)
-	}
-
-	// Expected PeriodType, SampleType and Sample.
-	expectedPeriodType := &profile.ValueType{Type: "space", Unit: "bytes"}
-	expectedSampleType := []*profile.ValueType{
-		{Type: "alloc_objects", Unit: "count"},
-		{Type: "alloc_space", Unit: "bytes"},
-		{Type: "inuse_objects", Unit: "count"},
-		{Type: "inuse_space", Unit: "bytes"},
-	}
-	// Expected samples, with values unsampled according to the profiling rate.
-	expectedSample := []*profile.Sample{
-		{Value: []int64{2050, 2099200, 1537, 1574400}, Location: []*profile.Location{
-			{ID: 1, Mapping: mprof.Mapping[0], Address: address1},
-			{ID: 2, Mapping: mprof.Mapping[1], Address: address2},
-		}},
-		{Value: []int64{1, 829411, 1, 829411}, Location: []*profile.Location{
-			{ID: 3, Mapping: mprof.Mapping[1], Address: address2 + 1},
-			{ID: 4, Mapping: mprof.Mapping[1], Address: address2 + 2},
-		}},
-		{Value: []int64{1, 829411, 0, 0}, Location: []*profile.Location{
-			{ID: 5, Mapping: mprof.Mapping[0], Address: address1 + 1},
-			{ID: 6, Mapping: mprof.Mapping[0], Address: address1 + 2},
-			{ID: 7, Mapping: mprof.Mapping[1], Address: address2 + 3},
-		}},
-	}
-
-	if p.Period != 512*1024 {
-		t.Fatalf("Sampling periods do not match")
-	}
-	if !reflect.DeepEqual(p.PeriodType, expectedPeriodType) {
-		t.Fatalf("Period types do not match")
-	}
-	if !reflect.DeepEqual(p.SampleType, expectedSampleType) {
-		t.Fatalf("Sample types do not match")
-	}
-	if !reflect.DeepEqual(p.Sample, expectedSample) {
-		t.Fatalf("Samples do not match: Expected: %v, Got:%v", getSampleAsString(expectedSample),
-			getSampleAsString(p.Sample))
-	}
-}
-
-func testMemRecords(a1, a2 uint64) ([]runtime.MemProfileRecord, int64) {
-	addr1, addr2 := uintptr(a1), uintptr(a2)
-	rate := int64(512 * 1024)
-	rec := []runtime.MemProfileRecord{
-		{4096, 1024, 4, 1, [32]uintptr{addr1, addr2}},
-		{512 * 1024, 0, 1, 0, [32]uintptr{addr2 + 1, addr2 + 2}},
-		{512 * 1024, 512 * 1024, 1, 1, [32]uintptr{addr1 + 1, addr1 + 2, addr2 + 3}},
-	}
-	return rec, rate
-}
diff --git a/libgo/go/runtime/pprof/internal/protopprof/protopprof.go b/libgo/go/runtime/pprof/internal/protopprof/protopprof.go
deleted file mode 100644
index 5d269c4..0000000
--- a/libgo/go/runtime/pprof/internal/protopprof/protopprof.go
+++ /dev/null
@@ -1,105 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package protopprof converts the runtime's raw profile logs
-// to Profile structs containing a representation of the pprof
-// protocol buffer profile format.
-package protopprof
-
-import (
-	"fmt"
-	"os"
-	"runtime"
-	"time"
-	"unsafe"
-
-	"internal/pprof/profile"
-)
-
-// TranslateCPUProfile parses binary CPU profiling stack trace data
-// generated by runtime.CPUProfile() into a profile struct.
-func TranslateCPUProfile(b []byte, startTime time.Time) (*profile.Profile, error) {
-	const wordSize = unsafe.Sizeof(uintptr(0))
-	const minRawProfile = 5 * wordSize // Need a minimum of 5 words.
-	if uintptr(len(b)) < minRawProfile {
-		return nil, fmt.Errorf("truncated profile")
-	}
-	n := int(uintptr(len(b)) / wordSize)
-	data := ((*[1 << 28]uintptr)(unsafe.Pointer(&b[0])))[:n:n]
-	period := data[3]
-	data = data[5:] // skip header
-
-	// profile initialization taken from pprof tool
-	p := &profile.Profile{
-		Period:     int64(period) * 1000,
-		PeriodType: &profile.ValueType{Type: "cpu", Unit: "nanoseconds"},
-		SampleType: []*profile.ValueType{
-			{Type: "samples", Unit: "count"},
-			{Type: "cpu", Unit: "nanoseconds"},
-		},
-		TimeNanos:     int64(startTime.UnixNano()),
-		DurationNanos: time.Since(startTime).Nanoseconds(),
-	}
-	// Parse CPU samples from the profile.
-	locs := make(map[uint64]*profile.Location)
-	for len(b) > 0 {
-		if len(data) < 2 || uintptr(len(data)) < 2+data[1] {
-			return nil, fmt.Errorf("truncated profile")
-		}
-		count := data[0]
-		nstk := data[1]
-		if uintptr(len(data)) < 2+nstk {
-			return nil, fmt.Errorf("truncated profile")
-		}
-		stk := data[2 : 2+nstk]
-		data = data[2+nstk:]
-
-		if count == 0 && nstk == 1 && stk[0] == 0 {
-			// end of data marker
-			break
-		}
-
-		sloc := make([]*profile.Location, len(stk))
-		for i, addr := range stk {
-			addr := uint64(addr)
-			// Addresses from stack traces point to the next instruction after
-			// each call.  Adjust by -1 to land somewhere on the actual call
-			// (except for the leaf, which is not a call).
-			if i > 0 {
-				addr--
-			}
-			loc := locs[addr]
-			if loc == nil {
-				loc = &profile.Location{
-					ID:      uint64(len(p.Location) + 1),
-					Address: addr,
-				}
-				locs[addr] = loc
-				p.Location = append(p.Location, loc)
-			}
-			sloc[i] = loc
-		}
-		p.Sample = append(p.Sample, &profile.Sample{
-			Value:    []int64{int64(count), int64(count) * int64(p.Period)},
-			Location: sloc,
-		})
-	}
-
-	if runtime.GOOS == "linux" {
-		if err := addMappings(p); err != nil {
-			return nil, err
-		}
-	}
-	return p, nil
-}
-
-func addMappings(p *profile.Profile) error {
-	// Parse memory map from /proc/self/maps
-	f, err := os.Open("/proc/self/maps")
-	if err != nil {
-		return err
-	}
-	defer f.Close()
-	return p.ParseMemoryMap(f)
-}
diff --git a/libgo/go/runtime/pprof/internal/protopprof/protopprof_test.go b/libgo/go/runtime/pprof/internal/protopprof/protopprof_test.go
deleted file mode 100644
index f1937b5..0000000
--- a/libgo/go/runtime/pprof/internal/protopprof/protopprof_test.go
+++ /dev/null
@@ -1,171 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package protopprof
-
-import (
-	"bytes"
-	"fmt"
-	"internal/pprof/profile"
-	"io/ioutil"
-	"reflect"
-	"runtime"
-	"testing"
-	"time"
-	"unsafe"
-)
-
-// Helper function to initialize empty cpu profile with sampling period provided.
-func createEmptyProfileWithPeriod(t *testing.T, periodMs uint64) bytes.Buffer {
-	// Mock the sample header produced by cpu profiler. Write a sample
-	// period of 2000 microseconds, followed by no samples.
-	buf := new(bytes.Buffer)
-	// Profile header is as follows:
-	// The first, third and fifth words are 0. The second word is 3.
-	// The fourth word is the period.
-	// EOD marker:
-	// The sixth word -- count is initialized to 0 above.
-	// The code below sets the seventh word -- nstk to 1
-	// The eighth word -- addr is initialized to 0 above.
-	words := []int{0, 3, 0, int(periodMs), 0, 0, 1, 0}
-	n := int(unsafe.Sizeof(0)) * len(words)
-	data := ((*[1 << 29]byte)(unsafe.Pointer(&words[0])))[:n:n]
-	if _, err := buf.Write(data); err != nil {
-		t.Fatalf("createEmptyProfileWithPeriod failed: %v", err)
-	}
-	return *buf
-}
-
-// Helper function to initialize cpu profile with two sample values.
-func createProfileWithTwoSamples(t *testing.T, periodMs uintptr, count1 uintptr, count2 uintptr,
-	address1 uintptr, address2 uintptr) bytes.Buffer {
-	// Mock the sample header produced by cpu profiler. Write a sample
-	// period of 2000 microseconds, followed by no samples.
-	buf := new(bytes.Buffer)
-	words := []uintptr{0, 3, 0, uintptr(periodMs), 0, uintptr(count1), 2,
-		uintptr(address1), uintptr(address1 + 2),
-		uintptr(count2), 2, uintptr(address2), uintptr(address2 + 2),
-		0, 1, 0}
-	for _, n := range words {
-		var err error
-		switch unsafe.Sizeof(int(0)) {
-		case 8:
-			_, err = buf.Write((*[8]byte)(unsafe.Pointer(&n))[:8:8])
-		case 4:
-			_, err = buf.Write((*[4]byte)(unsafe.Pointer(&n))[:4:4])
-		}
-		if err != nil {
-			t.Fatalf("createProfileWithTwoSamples failed: %v", err)
-		}
-	}
-	return *buf
-}
-
-// Tests TranslateCPUProfile parses correct sampling period in an otherwise empty cpu profile.
-func TestTranlateCPUProfileSamplingPeriod(t *testing.T) {
-	// A test server with mock cpu profile data.
-	var buf bytes.Buffer
-
-	startTime := time.Now()
-	b := createEmptyProfileWithPeriod(t, 2000)
-	p, err := TranslateCPUProfile(b.Bytes(), startTime)
-	if err != nil {
-		t.Fatalf("translate failed: %v", err)
-	}
-	if err := p.Write(&buf); err != nil {
-		t.Fatalf("write failed: %v", err)
-	}
-
-	p, err = profile.Parse(&buf)
-	if err != nil {
-		t.Fatalf("Could not parse Profile profile: %v", err)
-	}
-
-	// Expected PeriodType and SampleType.
-	expectedPeriodType := &profile.ValueType{Type: "cpu", Unit: "nanoseconds"}
-	expectedSampleType := []*profile.ValueType{
-		{Type: "samples", Unit: "count"},
-		{Type: "cpu", Unit: "nanoseconds"},
-	}
-	if p.Period != 2000*1000 || !reflect.DeepEqual(p.PeriodType, expectedPeriodType) ||
-		!reflect.DeepEqual(p.SampleType, expectedSampleType) || p.Sample != nil {
-		t.Fatalf("Unexpected Profile fields")
-	}
-}
-
-func getSampleAsString(sample []*profile.Sample) string {
-	var str string
-	for _, x := range sample {
-		for _, y := range x.Location {
-			if y.Mapping != nil {
-				str += fmt.Sprintf("Mapping:%v\n", *y.Mapping)
-			}
-			str += fmt.Sprintf("Location:%v\n", y)
-		}
-		str += fmt.Sprintf("Sample:%v\n", *x)
-	}
-	return str
-}
-
-// Tests TranslateCPUProfile parses a cpu profile with sample values present.
-func TestTranslateCPUProfileWithSamples(t *testing.T) {
-	if runtime.GOOS != "linux" {
-		t.Skip("test requires a system with /proc/self/maps")
-	}
-	// Figure out two addresses from /proc/self/maps.
-	mmap, err := ioutil.ReadFile("/proc/self/maps")
-	if err != nil {
-		t.Fatal("Cannot read /proc/self/maps")
-	}
-	rd := bytes.NewReader(mmap)
-	mprof := &profile.Profile{}
-	if err = mprof.ParseMemoryMap(rd); err != nil {
-		t.Fatalf("Cannot parse /proc/self/maps")
-	}
-	if len(mprof.Mapping) < 2 {
-		// It is possible for a binary to only have 1 executable
-		// region of memory.
-		t.Skipf("need 2 or more mappings, got %v", len(mprof.Mapping))
-	}
-	address1 := mprof.Mapping[0].Start
-	address2 := mprof.Mapping[1].Start
-	// A test server with mock cpu profile data.
-
-	startTime := time.Now()
-	b := createProfileWithTwoSamples(t, 2000, 20, 40, uintptr(address1), uintptr(address2))
-	p, err := TranslateCPUProfile(b.Bytes(), startTime)
-
-	if err != nil {
-		t.Fatalf("Could not parse Profile profile: %v", err)
-	}
-	// Expected PeriodType, SampleType and Sample.
-	expectedPeriodType := &profile.ValueType{Type: "cpu", Unit: "nanoseconds"}
-	expectedSampleType := []*profile.ValueType{
-		{Type: "samples", Unit: "count"},
-		{Type: "cpu", Unit: "nanoseconds"},
-	}
-	expectedSample := []*profile.Sample{
-		{Value: []int64{20, 20 * 2000 * 1000}, Location: []*profile.Location{
-			{ID: 1, Mapping: mprof.Mapping[0], Address: address1},
-			{ID: 2, Mapping: mprof.Mapping[0], Address: address1 + 1},
-		}},
-		{Value: []int64{40, 40 * 2000 * 1000}, Location: []*profile.Location{
-			{ID: 3, Mapping: mprof.Mapping[1], Address: address2},
-			{ID: 4, Mapping: mprof.Mapping[1], Address: address2 + 1},
-		}},
-	}
-	if p.Period != 2000*1000 {
-		t.Fatalf("Sampling periods do not match")
-	}
-	if !reflect.DeepEqual(p.PeriodType, expectedPeriodType) {
-		t.Fatalf("Period types do not match")
-	}
-	if !reflect.DeepEqual(p.SampleType, expectedSampleType) {
-		t.Fatalf("Sample types do not match")
-	}
-	if !reflect.DeepEqual(p.Sample, expectedSample) {
-		t.Fatalf("Samples do not match: Expected: %v, Got:%v", getSampleAsString(expectedSample),
-			getSampleAsString(p.Sample))
-	}
-}
diff --git a/libgo/go/runtime/pprof/label.go b/libgo/go/runtime/pprof/label.go
new file mode 100644
index 0000000..35647ee
--- /dev/null
+++ b/libgo/go/runtime/pprof/label.go
@@ -0,0 +1,85 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"context"
+)
+
+type label struct {
+	key   string
+	value string
+}
+
+// LabelSet is a set of labels.
+type LabelSet struct {
+	list []label
+}
+
+// labelContextKey is the type of contextKeys used for profiler labels.
+type labelContextKey struct{}
+
+func labelValue(ctx context.Context) labelMap {
+	labels, _ := ctx.Value(labelContextKey{}).(*labelMap)
+	if labels == nil {
+		return labelMap(nil)
+	}
+	return *labels
+}
+
+// labelMap is the representation of the label set held in the context type.
+// This is an initial implementation, but it will be replaced with something
+// that admits incremental immutable modification more efficiently.
+type labelMap map[string]string
+
+// WithLabels returns a new context.Context with the given labels added.
+// A label overwrites a prior label with the same key.
+func WithLabels(ctx context.Context, labels LabelSet) context.Context {
+	childLabels := make(labelMap)
+	parentLabels := labelValue(ctx)
+	// TODO(matloob): replace the map implementation with something
+	// more efficient so creating a child context WithLabels doesn't need
+	// to clone the map.
+	for k, v := range parentLabels {
+		childLabels[k] = v
+	}
+	for _, label := range labels.list {
+		childLabels[label.key] = label.value
+	}
+	return context.WithValue(ctx, labelContextKey{}, &childLabels)
+}
+
+// Labels takes an even number of strings representing key-value pairs
+// and makes a LabelSet containing them.
+// A label overwrites a prior label with the same key.
+func Labels(args ...string) LabelSet {
+	if len(args)%2 != 0 {
+		panic("uneven number of arguments to pprof.Labels")
+	}
+	labels := LabelSet{}
+	for i := 0; i+1 < len(args); i += 2 {
+		labels.list = append(labels.list, label{key: args[i], value: args[i+1]})
+	}
+	return labels
+}
+
+// Label returns the value of the label with the given key on ctx, and a boolean indicating
+// whether that label exists.
+func Label(ctx context.Context, key string) (string, bool) {
+	ctxLabels := labelValue(ctx)
+	v, ok := ctxLabels[key]
+	return v, ok
+}
+
+// ForLabels invokes f with each label set on the context.
+// The function f should return true to continue iteration or false to stop iteration early.
+func ForLabels(ctx context.Context, f func(key, value string) bool) {
+	ctxLabels := labelValue(ctx)
+	for k, v := range ctxLabels {
+		if !f(k, v) {
+			break
+		}
+	}
+}
diff --git a/libgo/go/runtime/pprof/label_test.go b/libgo/go/runtime/pprof/label_test.go
new file mode 100644
index 0000000..240445f
--- /dev/null
+++ b/libgo/go/runtime/pprof/label_test.go
@@ -0,0 +1,82 @@
+package pprof
+
+import (
+	"context"
+	"reflect"
+	"sort"
+	"testing"
+)
+
+func labelsSorted(ctx context.Context) []label {
+	ls := []label{}
+	ForLabels(ctx, func(key, value string) bool {
+		ls = append(ls, label{key, value})
+		return true
+	})
+	sort.Sort(labelSorter(ls))
+	return ls
+}
+
+type labelSorter []label
+
+func (s labelSorter) Len() int           { return len(s) }
+func (s labelSorter) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+func (s labelSorter) Less(i, j int) bool { return s[i].key < s[j].key }
+
+func TestContextLabels(t *testing.T) {
+	// Background context starts with no lablels.
+	ctx := context.Background()
+	labels := labelsSorted(ctx)
+	if len(labels) != 0 {
+		t.Errorf("labels on background context: want [], got %v ", labels)
+	}
+
+	// Add a single label.
+	ctx = WithLabels(ctx, Labels("key", "value"))
+	// Retrieve it with Label.
+	v, ok := Label(ctx, "key")
+	if !ok || v != "value" {
+		t.Errorf(`Label(ctx, "key"): got %v, %v; want "value", ok`, v, ok)
+	}
+	gotLabels := labelsSorted(ctx)
+	wantLabels := []label{{"key", "value"}}
+	if !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("(sorted) labels on context: got %v, want %v", gotLabels, wantLabels)
+	}
+
+	// Add a label with a different key.
+	ctx = WithLabels(ctx, Labels("key2", "value2"))
+	v, ok = Label(ctx, "key2")
+	if !ok || v != "value2" {
+		t.Errorf(`Label(ctx, "key2"): got %v, %v; want "value2", ok`, v, ok)
+	}
+	gotLabels = labelsSorted(ctx)
+	wantLabels = []label{{"key", "value"}, {"key2", "value2"}}
+	if !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("(sorted) labels on context: got %v, want %v", gotLabels, wantLabels)
+	}
+
+	// Add label with first key to test label replacement.
+	ctx = WithLabels(ctx, Labels("key", "value3"))
+	v, ok = Label(ctx, "key")
+	if !ok || v != "value3" {
+		t.Errorf(`Label(ctx, "key3"): got %v, %v; want "value3", ok`, v, ok)
+	}
+	gotLabels = labelsSorted(ctx)
+	wantLabels = []label{{"key", "value3"}, {"key2", "value2"}}
+	if !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("(sorted) labels on context: got %v, want %v", gotLabels, wantLabels)
+	}
+
+	// Labels called with two labels with the same key should pick the second.
+	ctx = WithLabels(ctx, Labels("key4", "value4a", "key4", "value4b"))
+	v, ok = Label(ctx, "key4")
+	if !ok || v != "value4b" {
+		t.Errorf(`Label(ctx, "key4"): got %v, %v; want "value4b", ok`, v, ok)
+	}
+	gotLabels = labelsSorted(ctx)
+	wantLabels = []label{{"key", "value3"}, {"key2", "value2"}, {"key4", "value4b"}}
+	if !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("(sorted) labels on context: got %v, want %v", gotLabels, wantLabels)
+	}
+}
diff --git a/libgo/go/runtime/pprof/map.go b/libgo/go/runtime/pprof/map.go
new file mode 100644
index 0000000..a271ad0
--- /dev/null
+++ b/libgo/go/runtime/pprof/map.go
@@ -0,0 +1,89 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import "unsafe"
+
+// A profMap is a map from (stack, tag) to mapEntry.
+// It grows without bound, but that's assumed to be OK.
+type profMap struct {
+	hash    map[uintptr]*profMapEntry
+	all     *profMapEntry
+	last    *profMapEntry
+	free    []profMapEntry
+	freeStk []uintptr
+}
+
+// A profMapEntry is a single entry in the profMap.
+type profMapEntry struct {
+	nextHash *profMapEntry // next in hash list
+	nextAll  *profMapEntry // next in list of all entries
+	stk      []uintptr
+	tag      unsafe.Pointer
+	count    int64
+}
+
+func (m *profMap) lookup(stk []uint64, tag unsafe.Pointer) *profMapEntry {
+	// Compute hash of (stk, tag).
+	h := uintptr(0)
+	for _, x := range stk {
+		h = h<<8 | (h >> (8 * (unsafe.Sizeof(h) - 1)))
+		h += uintptr(x) * 41
+	}
+	h = h<<8 | (h >> (8 * (unsafe.Sizeof(h) - 1)))
+	h += uintptr(tag) * 41
+
+	// Find entry if present.
+	var last *profMapEntry
+Search:
+	for e := m.hash[h]; e != nil; last, e = e, e.nextHash {
+		if len(e.stk) != len(stk) || e.tag != tag {
+			continue
+		}
+		for j := range stk {
+			if e.stk[j] != uintptr(stk[j]) {
+				continue Search
+			}
+		}
+		// Move to front.
+		if last != nil {
+			last.nextHash = e.nextHash
+			e.nextHash = m.hash[h]
+			m.hash[h] = e
+		}
+		return e
+	}
+
+	// Add new entry.
+	if len(m.free) < 1 {
+		m.free = make([]profMapEntry, 128)
+	}
+	e := &m.free[0]
+	m.free = m.free[1:]
+	e.nextHash = m.hash[h]
+	e.tag = tag
+
+	if len(m.freeStk) < len(stk) {
+		m.freeStk = make([]uintptr, 1024)
+	}
+	e.stk = m.freeStk[:len(stk)]
+	m.freeStk = m.freeStk[len(stk):]
+
+	for j := range stk {
+		e.stk[j] = uintptr(stk[j])
+	}
+	if m.hash == nil {
+		m.hash = make(map[uintptr]*profMapEntry)
+	}
+	m.hash[h] = e
+	if m.all == nil {
+		m.all = e
+		m.last = e
+	} else {
+		m.last.nextAll = e
+		m.last = e
+	}
+	return e
+}
diff --git a/libgo/go/runtime/pprof/mprof_test.go b/libgo/go/runtime/pprof/mprof_test.go
index 5ebd46b..5d77a1d 100644
--- a/libgo/go/runtime/pprof/mprof_test.go
+++ b/libgo/go/runtime/pprof/mprof_test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package pprof_test
+package pprof
 
 import (
 	"bytes"
@@ -10,7 +10,6 @@
 	"reflect"
 	"regexp"
 	"runtime"
-	. "runtime/pprof"
 	"testing"
 	"unsafe"
 )
@@ -87,26 +86,26 @@
 	tests := []string{
 
 		fmt.Sprintf(`%v: %v \[%v: %v\] @ 0x[0-9,a-f x]+
-#	0x[0-9,a-f]+	pprof_test\.allocatePersistent1K\+0x[0-9,a-f]+	.*/mprof_test\.go:41
-#	0x[0-9,a-f]+	runtime_pprof_test\.TestMemoryProfiler\+0x[0-9,a-f]+	.*/mprof_test\.go:75
+#	0x[0-9,a-f]+	pprof\.allocatePersistent1K\+0x[0-9,a-f]+	.*/mprof_test\.go:40
+#	0x[0-9,a-f]+	runtime_pprof\.TestMemoryProfiler\+0x[0-9,a-f]+	.*/mprof_test\.go:74
 `, 32*memoryProfilerRun, 1024*memoryProfilerRun, 32*memoryProfilerRun, 1024*memoryProfilerRun),
 
 		fmt.Sprintf(`0: 0 \[%v: %v\] @ 0x[0-9,a-f x]+
-#	0x[0-9,a-f]+	pprof_test\.allocateTransient1M\+0x[0-9,a-f]+	.*/mprof_test.go:22
-#	0x[0-9,a-f]+	runtime_pprof_test\.TestMemoryProfiler\+0x[0-9,a-f]+	.*/mprof_test.go:73
+#	0x[0-9,a-f]+	pprof\.allocateTransient1M\+0x[0-9,a-f]+	.*/mprof_test.go:21
+#	0x[0-9,a-f]+	runtime_pprof\.TestMemoryProfiler\+0x[0-9,a-f]+	.*/mprof_test.go:72
 `, (1<<10)*memoryProfilerRun, (1<<20)*memoryProfilerRun),
 
 		// This should start with "0: 0" but gccgo's imprecise
 		// GC means that sometimes the value is not collected.
 		fmt.Sprintf(`(0|%v): (0|%v) \[%v: %v\] @ 0x[0-9,a-f x]+
-#	0x[0-9,a-f]+	pprof_test\.allocateTransient2M\+0x[0-9,a-f]+	.*/mprof_test.go:28
-#	0x[0-9,a-f]+	runtime_pprof_test\.TestMemoryProfiler\+0x[0-9,a-f]+	.*/mprof_test.go:74
+#	0x[0-9,a-f]+	pprof\.allocateTransient2M\+0x[0-9,a-f]+	.*/mprof_test.go:27
+#	0x[0-9,a-f]+	runtime_pprof\.TestMemoryProfiler\+0x[0-9,a-f]+	.*/mprof_test.go:73
 `, memoryProfilerRun, (2<<20)*memoryProfilerRun, memoryProfilerRun, (2<<20)*memoryProfilerRun),
 
 		// This should start with "0: 0" but gccgo's imprecise
 		// GC means that sometimes the value is not collected.
 		fmt.Sprintf(`(0|%v): (0|%v) \[%v: %v\] @( 0x[0-9,a-f]+)+
-#	0x[0-9,a-f]+	pprof_test\.allocateReflectTransient\+0x[0-9,a-f]+	.*/mprof_test.go:49
+#	0x[0-9,a-f]+	pprof\.allocateReflectTransient\+0x[0-9,a-f]+	.*/mprof_test.go:48
 `, memoryProfilerRun, (2<<20)*memoryProfilerRun, memoryProfilerRun, (2<<20)*memoryProfilerRun),
 	}
 
diff --git a/libgo/go/runtime/pprof/pprof.go b/libgo/go/runtime/pprof/pprof.go
index 0db1ded..a57b69d 100644
--- a/libgo/go/runtime/pprof/pprof.go
+++ b/libgo/go/runtime/pprof/pprof.go
@@ -33,7 +33,9 @@
 //            }
 //            defer pprof.StopCPUProfile()
 //        }
-//        ...
+//
+//        // ... rest of the program ...
+//
 //        if *memprofile != "" {
 //            f, err := os.Create(*memprofile)
 //            if err != nil {
@@ -73,15 +75,14 @@
 	"bufio"
 	"bytes"
 	"fmt"
-	"internal/pprof/profile"
 	"io"
 	"runtime"
-	"runtime/pprof/internal/protopprof"
 	"sort"
 	"strings"
 	"sync"
 	"text/tabwriter"
 	"time"
+	"unsafe"
 )
 
 // BUG(rsc): Profiles are only as good as the kernel support used to generate them.
@@ -183,6 +184,8 @@
 // If a profile with that name already exists, NewProfile panics.
 // The convention is to use a 'import/path.' prefix to create
 // separate name spaces for each package.
+// For compatibility with various tools that read pprof data,
+// profile names should not contain spaces.
 func NewProfile(name string) *Profile {
 	lockProfiles()
 	defer unlockProfiles()
@@ -264,13 +267,18 @@
 
 	stk := make([]uintptr, 32)
 	n := runtime.Callers(skip+1, stk[:])
+	stk = stk[:n]
+	if len(stk) == 0 {
+		// The value for skip is too large, and there's no stack trace to record.
+		stk = []uintptr{funcPC(lostProfileEvent) + 1}
+	}
 
 	p.mu.Lock()
 	defer p.mu.Unlock()
 	if p.m[value] != nil {
 		panic("pprof: Profile.Add of duplicate value")
 	}
-	p.m[value] = stk[:n]
+	p.m[value] = stk
 }
 
 // Remove removes the execution stack associated with value from the profile.
@@ -303,8 +311,8 @@
 	}
 
 	// Obtain consistent snapshot under lock; then process without lock.
-	all := make([][]uintptr, 0, len(p.m))
 	p.mu.Lock()
+	all := make([][]uintptr, 0, len(p.m))
 	for _, stk := range p.m {
 		all = append(all, stk)
 	}
@@ -380,35 +388,29 @@
 	}
 
 	// Output profile in protobuf form.
-	prof := &profile.Profile{
-		PeriodType: &profile.ValueType{Type: name, Unit: "count"},
-		Period:     1,
-		Sample:     make([]*profile.Sample, 0, len(keys)),
-		SampleType: []*profile.ValueType{{Type: name, Unit: "count"}},
-	}
-	locMap := make(map[uintptr]*profile.Location)
+	b := newProfileBuilder(w)
+	b.pbValueType(tagProfile_PeriodType, name, "count")
+	b.pb.int64Opt(tagProfile_Period, 1)
+	b.pbValueType(tagProfile_SampleType, name, "count")
+
+	values := []int64{0}
+	var locs []uint64
 	for _, k := range keys {
-		stk := p.Stack(index[k])
-		c := count[k]
-		locs := make([]*profile.Location, len(stk))
-		for i, addr := range stk {
-			loc := locMap[addr]
-			if loc == nil {
-				loc = &profile.Location{
-					ID:      uint64(len(locMap) + 1),
-					Address: uint64(addr - 1),
-				}
-				prof.Location = append(prof.Location, loc)
-				locMap[addr] = loc
+		values[0] = int64(count[k])
+		locs = locs[:0]
+		for _, addr := range p.Stack(index[k]) {
+			// For count profiles, all stack addresses are
+			// return PCs, which is what locForPC expects.
+			l := b.locForPC(addr)
+			if l == 0 { // runtime.goexit
+				continue
 			}
-			locs[i] = loc
+			locs = append(locs, l)
 		}
-		prof.Sample = append(prof.Sample, &profile.Sample{
-			Location: locs,
-			Value:    []int64{int64(c)},
-		})
+		b.pbSample(values, locs, nil)
 	}
-	return prof.Write(w)
+	b.build()
+	return nil
 }
 
 // keysByCount sorts keys with higher counts first, breaking ties by key string order.
@@ -510,8 +512,7 @@
 	}
 
 	if debug == 0 {
-		pp := protopprof.EncodeMemProfile(p, int64(runtime.MemProfileRate), time.Now())
-		return pp.Write(w)
+		return writeHeapProto(w, p, int64(runtime.MemProfileRate))
 	}
 
 	sort.Slice(p, func(i, j int) bool { return p[i].InUseBytes() > p[j].InUseBytes() })
@@ -576,8 +577,12 @@
 	fmt.Fprintf(w, "# OtherSys = %d\n", s.OtherSys)
 
 	fmt.Fprintf(w, "# NextGC = %d\n", s.NextGC)
+	fmt.Fprintf(w, "# LastGC = %d\n", s.LastGC)
 	fmt.Fprintf(w, "# PauseNs = %d\n", s.PauseNs)
+	fmt.Fprintf(w, "# PauseEnd = %d\n", s.PauseEnd)
 	fmt.Fprintf(w, "# NumGC = %d\n", s.NumGC)
+	fmt.Fprintf(w, "# NumForcedGC = %d\n", s.NumForcedGC)
+	fmt.Fprintf(w, "# GCCPUFraction = %v\n", s.GCCPUFraction)
 	fmt.Fprintf(w, "# DebugGC = %v\n", s.DebugGC)
 
 	tw.Flush()
@@ -703,30 +708,32 @@
 	return nil
 }
 
+// readProfile, provided by the runtime, returns the next chunk of
+// binary CPU profiling stack trace data, blocking until data is available.
+// If profiling is turned off and all the profile data accumulated while it was
+// on has been returned, readProfile returns eof=true.
+// The caller must save the returned data and tags before calling readProfile again.
+func readProfile() (data []uint64, tags []unsafe.Pointer, eof bool)
+
 func profileWriter(w io.Writer) {
-	startTime := time.Now()
-	// This will buffer the entire profile into buf and then
-	// translate it into a profile.Profile structure. This will
-	// create two copies of all the data in the profile in memory.
-	// TODO(matloob): Convert each chunk of the proto output and
-	// stream it out instead of converting the entire profile.
-	var buf bytes.Buffer
+	b := newProfileBuilder(w)
+	var err error
 	for {
-		data := runtime.CPUProfile()
-		if data == nil {
+		time.Sleep(100 * time.Millisecond)
+		data, tags, eof := readProfile()
+		if e := b.addCPUData(data, tags); e != nil && err == nil {
+			err = e
+		}
+		if eof {
 			break
 		}
-		buf.Write(data)
 	}
-
-	profile, err := protopprof.TranslateCPUProfile(buf.Bytes(), startTime)
 	if err != nil {
 		// The runtime should never produce an invalid or truncated profile.
 		// It drops records that can't fit into its log buffers.
-		panic(fmt.Errorf("could not translate binary profile to proto format: %v", err))
+		panic("runtime/pprof: converting profile: " + err.Error())
 	}
-
-	profile.Write(w)
+	b.build()
 	cpu.done <- true
 }
 
diff --git a/libgo/go/runtime/pprof/pprof_test.go b/libgo/go/runtime/pprof/pprof_test.go
index 6034058..9e5e403 100644
--- a/libgo/go/runtime/pprof/pprof_test.go
+++ b/libgo/go/runtime/pprof/pprof_test.go
@@ -4,13 +4,12 @@
 
 // +build !nacl
 
-package pprof_test
+package pprof
 
 import (
 	"bytes"
-	"compress/gzip"
+	"context"
 	"fmt"
-	"internal/pprof/profile"
 	"internal/testenv"
 	"io"
 	"io/ioutil"
@@ -19,14 +18,15 @@
 	"os/exec"
 	"regexp"
 	"runtime"
-	. "runtime/pprof"
+	"runtime/pprof/internal/profile"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 )
 
-func cpuHogger(f func(), dur time.Duration) {
+func cpuHogger(f func() int, dur time.Duration) {
 	// We only need to get one 100 Hz clock tick, so we've got
 	// a large safety buffer.
 	// But do at least 500 iterations (which should take about 100ms),
@@ -46,7 +46,7 @@
 // The actual CPU hogging function.
 // Must not call other functions nor access heap/globals in the loop,
 // otherwise under race detector the samples will be in the race runtime.
-func cpuHog1() {
+func cpuHog1() int {
 	foo := salt1
 	for i := 0; i < 1e5; i++ {
 		if foo > 0 {
@@ -55,10 +55,10 @@
 			foo *= foo + 1
 		}
 	}
-	salt1 = foo
+	return foo
 }
 
-func cpuHog2() {
+func cpuHog2() int {
 	foo := salt2
 	for i := 0; i < 1e5; i++ {
 		if foo > 0 {
@@ -67,18 +67,18 @@
 			foo *= foo + 2
 		}
 	}
-	salt2 = foo
+	return foo
 }
 
 func TestCPUProfile(t *testing.T) {
-	testCPUProfile(t, []string{"pprof_test.cpuHog1"}, func(dur time.Duration) {
+	testCPUProfile(t, []string{"pprof.cpuHog1"}, func(dur time.Duration) {
 		cpuHogger(cpuHog1, dur)
 	})
 }
 
 func TestCPUProfileMultithreaded(t *testing.T) {
 	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(2))
-	testCPUProfile(t, []string{"pprof_test.cpuHog1", "pprof_test.cpuHog2"}, func(dur time.Duration) {
+	testCPUProfile(t, []string{"pprof.cpuHog1", "pprof.cpuHog2"}, func(dur time.Duration) {
 		c := make(chan int)
 		go func() {
 			cpuHogger(cpuHog1, dur)
@@ -89,18 +89,42 @@
 	})
 }
 
-func parseProfile(t *testing.T, valBytes []byte, f func(uintptr, []uintptr)) {
+func TestCPUProfileInlining(t *testing.T) {
+	testCPUProfile(t, []string{"pprof.inlinedCallee", "pprof.inlinedCaller"}, func(dur time.Duration) {
+		cpuHogger(inlinedCaller, dur)
+	})
+}
+
+func inlinedCaller() int {
+	inlinedCallee()
+	return 0
+}
+
+func inlinedCallee() {
+	// We could just use cpuHog1, but for loops prevent inlining
+	// right now. :(
+	foo := salt1
+	i := 0
+loop:
+	if foo > 0 {
+		foo *= foo
+	} else {
+		foo *= foo + 1
+	}
+	if i++; i < 1e5 {
+		goto loop
+	}
+	salt1 = foo
+}
+
+func parseProfile(t *testing.T, valBytes []byte, f func(uintptr, []*profile.Location, map[string][]string)) {
 	p, err := profile.Parse(bytes.NewReader(valBytes))
 	if err != nil {
 		t.Fatal(err)
 	}
 	for _, sample := range p.Sample {
 		count := uintptr(sample.Value[0])
-		stk := make([]uintptr, len(sample.Location))
-		for i := range sample.Location {
-			stk[i] = uintptr(sample.Location[i].Address)
-		}
-		f(count, stk)
+		f(count, sample.Location, sample.Label)
 	}
 }
 
@@ -124,8 +148,7 @@
 
 	const maxDuration = 5 * time.Second
 	// If we're running a long test, start with a long duration
-	// because some of the tests (e.g., TestStackBarrierProfiling)
-	// are trying to make sure something *doesn't* happen.
+	// for tests that try to make sure something *doesn't* happen.
 	duration := 5 * time.Second
 	if testing.Short() {
 		duration = 200 * time.Millisecond
@@ -169,32 +192,45 @@
 	t.FailNow()
 }
 
+func contains(slice []string, s string) bool {
+	for i := range slice {
+		if slice[i] == s {
+			return true
+		}
+	}
+	return false
+}
+
 func profileOk(t *testing.T, need []string, prof bytes.Buffer, duration time.Duration) (ok bool) {
 	ok = true
 
 	// Check that profile is well formed and contains need.
 	have := make([]uintptr, len(need))
 	var samples uintptr
-	parseProfile(t, prof.Bytes(), func(count uintptr, stk []uintptr) {
+	var buf bytes.Buffer
+	parseProfile(t, prof.Bytes(), func(count uintptr, stk []*profile.Location, labels map[string][]string) {
+		fmt.Fprintf(&buf, "%d:", count)
+		fprintStack(&buf, stk)
 		samples += count
-		for _, pc := range stk {
-			f := runtime.FuncForPC(pc)
-			if f == nil {
-				continue
+		for i, name := range need {
+			if semi := strings.Index(name, ";"); semi > -1 {
+				kv := strings.SplitN(name[semi+1:], "=", 2)
+				if len(kv) != 2 || !contains(labels[kv[0]], kv[1]) {
+					continue
+				}
+				name = name[:semi]
 			}
-			t.Log(f.Name(), count)
-			for i, name := range need {
-				if strings.Contains(f.Name(), name) {
-					have[i] += count
+			for _, loc := range stk {
+				for _, line := range loc.Line {
+					if strings.Contains(line.Function.Name, name) {
+						have[i] += count
+					}
 				}
 			}
-			if strings.Contains(f.Name(), "stackBarrier") {
-				// The runtime should have unwound this.
-				t.Fatalf("profile includes stackBarrier")
-			}
 		}
+		fmt.Fprintf(&buf, "\n")
 	})
-	t.Logf("total %d CPU profile samples collected", samples)
+	t.Logf("total %d CPU profile samples collected:\n%s", samples, buf.String())
 
 	if samples < 10 && runtime.GOOS == "windows" {
 		// On some windows machines we end up with
@@ -301,36 +337,43 @@
 
 		// Read profile to look for entries for runtime.gogo with an attempt at a traceback.
 		// The special entry
-		parseProfile(t, prof.Bytes(), func(count uintptr, stk []uintptr) {
+		parseProfile(t, prof.Bytes(), func(count uintptr, stk []*profile.Location, _ map[string][]string) {
 			// An entry with two frames with 'System' in its top frame
 			// exists to record a PC without a traceback. Those are okay.
 			if len(stk) == 2 {
-				f := runtime.FuncForPC(stk[1])
-				if f != nil && (f.Name() == "runtime._System" || f.Name() == "runtime._ExternalCode" || f.Name() == "runtime._GC") {
+				name := stk[1].Line[0].Function.Name
+				if name == "runtime._System" || name == "runtime._ExternalCode" || name == "runtime._GC" {
 					return
 				}
 			}
 
 			// Otherwise, should not see runtime.gogo.
 			// The place we'd see it would be the inner most frame.
-			f := runtime.FuncForPC(stk[0])
-			if f != nil && f.Name() == "runtime.gogo" {
+			name := stk[0].Line[0].Function.Name
+			if name == "runtime.gogo" {
 				var buf bytes.Buffer
-				for _, pc := range stk {
-					f := runtime.FuncForPC(pc)
-					if f == nil {
-						fmt.Fprintf(&buf, "%#x ?:0\n", pc)
-					} else {
-						file, line := f.FileLine(pc)
-						fmt.Fprintf(&buf, "%#x %s:%d\n", pc, file, line)
-					}
-				}
+				fprintStack(&buf, stk)
 				t.Fatalf("found profile entry for runtime.gogo:\n%s", buf.String())
 			}
 		})
 	}
 }
 
+func fprintStack(w io.Writer, stk []*profile.Location) {
+	for _, loc := range stk {
+		fmt.Fprintf(w, " %#x", loc.Address)
+		fmt.Fprintf(w, " (")
+		for i, line := range loc.Line {
+			if i > 0 {
+				fmt.Fprintf(w, " ")
+			}
+			fmt.Fprintf(w, "%s:%d", line.Function.Name, line.Line)
+		}
+		fmt.Fprintf(w, ")")
+	}
+	fmt.Fprintf(w, "\n")
+}
+
 // Test that profiling of division operations is okay, especially on ARM. See issue 6681.
 func TestMathBigDivide(t *testing.T) {
 	testCPUProfile(t, nil, func(duration time.Duration) {
@@ -351,111 +394,6 @@
 	})
 }
 
-func slurpString(r io.Reader) string {
-	slurp, _ := ioutil.ReadAll(r)
-	return string(slurp)
-}
-
-func getLinuxKernelConfig() string {
-	if f, err := os.Open("/proc/config"); err == nil {
-		defer f.Close()
-		return slurpString(f)
-	}
-	if f, err := os.Open("/proc/config.gz"); err == nil {
-		defer f.Close()
-		r, err := gzip.NewReader(f)
-		if err != nil {
-			return ""
-		}
-		return slurpString(r)
-	}
-	if f, err := os.Open("/boot/config"); err == nil {
-		defer f.Close()
-		return slurpString(f)
-	}
-	uname, _ := exec.Command("uname", "-r").Output()
-	if len(uname) > 0 {
-		if f, err := os.Open("/boot/config-" + strings.TrimSpace(string(uname))); err == nil {
-			defer f.Close()
-			return slurpString(f)
-		}
-	}
-	return ""
-}
-
-func haveLinuxHiresTimers() bool {
-	config := getLinuxKernelConfig()
-	return strings.Contains(config, "CONFIG_HIGH_RES_TIMERS=y")
-}
-
-func TestStackBarrierProfiling(t *testing.T) {
-	if (runtime.GOOS == "linux" && runtime.GOARCH == "arm") ||
-		runtime.GOOS == "openbsd" ||
-		runtime.GOOS == "solaris" ||
-		runtime.GOOS == "dragonfly" ||
-		runtime.GOOS == "freebsd" {
-		// This test currently triggers a large number of
-		// usleep(100)s. These kernels/arches have poor
-		// resolution timers, so this gives up a whole
-		// scheduling quantum. On Linux and the BSDs (and
-		// probably Solaris), profiling signals are only
-		// generated when a process completes a whole
-		// scheduling quantum, so this test often gets zero
-		// profiling signals and fails.
-		t.Skipf("low resolution timers inhibit profiling signals (golang.org/issue/13405)")
-		return
-	}
-
-	if runtime.GOOS == "linux" && strings.HasPrefix(runtime.GOARCH, "mips") {
-		if !haveLinuxHiresTimers() {
-			t.Skipf("low resolution timers inhibit profiling signals (golang.org/issue/13405, golang.org/issue/17936)")
-		}
-	}
-
-	if !strings.Contains(os.Getenv("GODEBUG"), "gcstackbarrierall=1") {
-		// Re-execute this test with constant GC and stack
-		// barriers at every frame.
-		testenv.MustHaveExec(t)
-		if runtime.GOARCH == "ppc64" || runtime.GOARCH == "ppc64le" {
-			t.Skip("gcstackbarrierall doesn't work on ppc64")
-		}
-		args := []string{"-test.run=TestStackBarrierProfiling"}
-		if testing.Short() {
-			args = append(args, "-test.short")
-		}
-		cmd := exec.Command(os.Args[0], args...)
-		cmd.Env = append([]string{"GODEBUG=gcstackbarrierall=1", "GOGC=1", "GOTRACEBACK=system"}, os.Environ()...)
-		if out, err := cmd.CombinedOutput(); err != nil {
-			t.Fatalf("subprocess failed with %v:\n%s", err, out)
-		}
-		return
-	}
-
-	testCPUProfile(t, nil, func(duration time.Duration) {
-		// In long mode, we're likely to get one or two
-		// samples in stackBarrier.
-		t := time.After(duration)
-		for {
-			deepStack(1000)
-			select {
-			case <-t:
-				return
-			default:
-			}
-		}
-	})
-}
-
-var x []byte
-
-func deepStack(depth int) int {
-	if depth == 0 {
-		return 0
-	}
-	x = make([]byte, 1024)
-	return deepStack(depth-1) + 1
-}
-
 // Operating systems that are expected to fail the tests. See issue 13841.
 var badOS = map[string]bool{
 	"darwin":    true,
@@ -474,46 +412,46 @@
 	}
 	tests := [...]TestCase{
 		{"chan recv", blockChanRecv, `
-[0-9]+ [0-9]+ @ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+
-#	0x[0-9,a-f]+	runtime\.chanrecv1\+0x[0-9,a-f]+	.*/src/runtime/chan.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.blockChanRecv\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.TestBlockProfile\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
+#	0x[0-9a-f]+	runtime\.chanrecv1\+0x[0-9a-f]+	.*/src/runtime/chan.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.blockChanRecv\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.TestBlockProfile\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
 `},
 		{"chan send", blockChanSend, `
-[0-9]+ [0-9]+ @ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+
-#	0x[0-9,a-f]+	runtime\.chansend1\+0x[0-9,a-f]+	.*/src/runtime/chan.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.blockChanSend\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.TestBlockProfile\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
+#	0x[0-9a-f]+	runtime\.chansend1\+0x[0-9a-f]+	.*/src/runtime/chan.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.blockChanSend\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.TestBlockProfile\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
 `},
 		{"chan close", blockChanClose, `
-[0-9]+ [0-9]+ @ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+
-#	0x[0-9,a-f]+	runtime\.chanrecv1\+0x[0-9,a-f]+	.*/src/runtime/chan.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.blockChanClose\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.TestBlockProfile\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
+#	0x[0-9a-f]+	runtime\.chanrecv1\+0x[0-9a-f]+	.*/src/runtime/chan.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.blockChanClose\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.TestBlockProfile\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
 `},
 		{"select recv async", blockSelectRecvAsync, `
-[0-9]+ [0-9]+ @ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+
-#	0x[0-9,a-f]+	runtime\.selectgo\+0x[0-9,a-f]+	.*/src/runtime/select.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.blockSelectRecvAsync\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.TestBlockProfile\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
+#	0x[0-9a-f]+	runtime\.selectgo\+0x[0-9a-f]+	.*/src/runtime/select.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.blockSelectRecvAsync\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.TestBlockProfile\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
 `},
 		{"select send sync", blockSelectSendSync, `
-[0-9]+ [0-9]+ @ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+
-#	0x[0-9,a-f]+	runtime\.selectgo\+0x[0-9,a-f]+	.*/src/runtime/select.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.blockSelectSendSync\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.TestBlockProfile\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
+#	0x[0-9a-f]+	runtime\.selectgo\+0x[0-9a-f]+	.*/src/runtime/select.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.blockSelectSendSync\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.TestBlockProfile\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
 `},
 		{"mutex", blockMutex, `
-[0-9]+ [0-9]+ @ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+
-#	0x[0-9,a-f]+	sync\.\(\*Mutex\)\.Lock\+0x[0-9,a-f]+	.*/src/sync/mutex\.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.blockMutex\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.TestBlockProfile\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
+#	0x[0-9a-f]+	sync\.\(\*Mutex\)\.Lock\+0x[0-9a-f]+	.*/src/sync/mutex\.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.blockMutex\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.TestBlockProfile\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
 `},
 		{"cond", blockCond, `
-[0-9]+ [0-9]+ @ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+ 0x[0-9,a-f]+
-#	0x[0-9,a-f]+	sync\.\(\*Cond\)\.Wait\+0x[0-9,a-f]+	.*/src/sync/cond\.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.blockCond\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
-#	0x[0-9,a-f]+	runtime/pprof_test\.TestBlockProfile\+0x[0-9,a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
+#	0x[0-9a-f]+	sync\.\(\*Cond\)\.Wait\+0x[0-9a-f]+	.*/src/sync/cond\.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.blockCond\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
+#	0x[0-9a-f]+	runtime/pprof\.TestBlockProfile\+0x[0-9a-f]+	.*/src/runtime/pprof/pprof_test.go:[0-9]+
 `},
 	}
 
@@ -608,6 +546,10 @@
 		time.Sleep(blockDelay)
 		mu.Unlock()
 	}()
+	// Note: Unlock releases mu before recording the mutex event,
+	// so it's theoretically possible for this to proceed and
+	// capture the profile before the event is recorded. As long
+	// as this is blocked before the unlock happens, it's okay.
 	mu.Lock()
 }
 
@@ -656,7 +598,7 @@
 	if ok, err := regexp.MatchString(r2, lines[3]); err != nil || !ok {
 		t.Errorf("%q didn't match %q", lines[3], r2)
 	}
-	r3 := "^#.*pprof_test.\\$nested.*$"
+	r3 := "^#.*pprof.\\$nested.*$"
 	match := false
 	for _, i := range []int{5, 6} {
 		if ok, _ := regexp.MatchString(r3, lines[i]); ok {
@@ -678,22 +620,26 @@
 	if runtime.Compiler == "gccgo" {
 		t.Skip("goroutine stacks not supported on gccgo")
 	}
-	if runtime.GOOS == "openbsd" {
-		testenv.SkipFlaky(t, 15156)
-	}
+
+	// Setting GOMAXPROCS to 1 ensures we can force all goroutines to the
+	// desired blocking point.
+	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(1))
+
 	c := make(chan int)
 	for i := 0; i < 100; i++ {
-		if i%10 == 0 {
+		switch {
+		case i%10 == 0:
 			go func1(c)
-			continue
-		}
-		if i%2 == 0 {
+		case i%2 == 0:
 			go func2(c)
-			continue
+		default:
+			go func3(c)
 		}
-		go func3(c)
+		// Let goroutines block on channel
+		for j := 0; j < 5; j++ {
+			runtime.Gosched()
+		}
 	}
-	time.Sleep(10 * time.Millisecond) // let goroutines block on channel
 
 	var w bytes.Buffer
 	goroutineProf := Lookup("goroutine")
@@ -756,3 +702,81 @@
 	}
 	return true
 }
+
+// Issue 18836.
+func TestEmptyCallStack(t *testing.T) {
+	t.Parallel()
+	var buf bytes.Buffer
+	p := NewProfile("test18836")
+	p.Add("foo", 47674)
+	p.WriteTo(&buf, 1)
+	p.Remove("foo")
+	got := buf.String()
+	prefix := "test18836 profile: total 1\n"
+	if !strings.HasPrefix(got, prefix) {
+		t.Fatalf("got:\n\t%q\nwant prefix:\n\t%q\n", got, prefix)
+	}
+	lostevent := "lostProfileEvent"
+	if !strings.Contains(got, lostevent) {
+		t.Fatalf("got:\n\t%q\ndoes not contain:\n\t%q\n", got, lostevent)
+	}
+}
+
+func TestCPUProfileLabel(t *testing.T) {
+	testCPUProfile(t, []string{"pprof.cpuHogger;key=value"}, func(dur time.Duration) {
+		Do(context.Background(), Labels("key", "value"), func(context.Context) {
+			cpuHogger(cpuHog1, dur)
+		})
+	})
+}
+
+func TestLabelRace(t *testing.T) {
+	// Test the race detector annotations for synchronization
+	// between settings labels and consuming them from the
+	// profile.
+	testCPUProfile(t, []string{"pprof.cpuHogger;key=value"}, func(dur time.Duration) {
+		start := time.Now()
+		var wg sync.WaitGroup
+		for time.Since(start) < dur {
+			for i := 0; i < 10; i++ {
+				wg.Add(1)
+				go func() {
+					Do(context.Background(), Labels("key", "value"), func(context.Context) {
+						cpuHogger(cpuHog1, time.Millisecond)
+					})
+					wg.Done()
+				}()
+			}
+			wg.Wait()
+		}
+	})
+}
+
+// Check that there is no deadlock when the program receives SIGPROF while in
+// 64bit atomics' critical section. Used to happen on mips{,le}. See #20146.
+func TestAtomicLoadStore64(t *testing.T) {
+	f, err := ioutil.TempFile("", "profatomic")
+	if err != nil {
+		t.Fatalf("TempFile: %v", err)
+	}
+	defer os.Remove(f.Name())
+	defer f.Close()
+
+	if err := StartCPUProfile(f); err != nil {
+		t.Fatal(err)
+	}
+	defer StopCPUProfile()
+
+	var flag uint64
+	done := make(chan bool, 1)
+
+	go func() {
+		for atomic.LoadUint64(&flag) == 0 {
+			runtime.Gosched()
+		}
+		done <- true
+	}()
+	time.Sleep(50 * time.Millisecond)
+	atomic.StoreUint64(&flag, 1)
+	<-done
+}
diff --git a/libgo/go/runtime/pprof/proto.go b/libgo/go/runtime/pprof/proto.go
new file mode 100644
index 0000000..5e1d71c
--- /dev/null
+++ b/libgo/go/runtime/pprof/proto.go
@@ -0,0 +1,515 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"bytes"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"runtime"
+	"sort"
+	"strconv"
+	"time"
+	"unsafe"
+)
+
+// lostProfileEvent is the function to which lost profiling
+// events are attributed.
+// (The name shows up in the pprof graphs.)
+func lostProfileEvent() { lostProfileEvent() }
+
+// funcPC returns the PC for the func value f.
+func funcPC(f interface{}) uintptr {
+	type iface struct {
+		tab  unsafe.Pointer
+		data unsafe.Pointer
+	}
+	i := (*iface)(unsafe.Pointer(&f))
+	return **(**uintptr)(i.data)
+}
+
+// A profileBuilder writes a profile incrementally from a
+// stream of profile samples delivered by the runtime.
+type profileBuilder struct {
+	start      time.Time
+	end        time.Time
+	havePeriod bool
+	period     int64
+	m          profMap
+
+	// encoding state
+	w         io.Writer
+	zw        *gzip.Writer
+	pb        protobuf
+	strings   []string
+	stringMap map[string]int
+	locs      map[uintptr]int
+	funcs     map[string]int // Package path-qualified function name to Function.ID
+	mem       []memMap
+}
+
+type memMap struct {
+	start uintptr
+	end   uintptr
+}
+
+const (
+	// message Profile
+	tagProfile_SampleType    = 1  // repeated ValueType
+	tagProfile_Sample        = 2  // repeated Sample
+	tagProfile_Mapping       = 3  // repeated Mapping
+	tagProfile_Location      = 4  // repeated Location
+	tagProfile_Function      = 5  // repeated Function
+	tagProfile_StringTable   = 6  // repeated string
+	tagProfile_DropFrames    = 7  // int64 (string table index)
+	tagProfile_KeepFrames    = 8  // int64 (string table index)
+	tagProfile_TimeNanos     = 9  // int64
+	tagProfile_DurationNanos = 10 // int64
+	tagProfile_PeriodType    = 11 // ValueType (really optional string???)
+	tagProfile_Period        = 12 // int64
+
+	// message ValueType
+	tagValueType_Type = 1 // int64 (string table index)
+	tagValueType_Unit = 2 // int64 (string table index)
+
+	// message Sample
+	tagSample_Location = 1 // repeated uint64
+	tagSample_Value    = 2 // repeated int64
+	tagSample_Label    = 3 // repeated Label
+
+	// message Label
+	tagLabel_Key = 1 // int64 (string table index)
+	tagLabel_Str = 2 // int64 (string table index)
+	tagLabel_Num = 3 // int64
+
+	// message Mapping
+	tagMapping_ID              = 1  // uint64
+	tagMapping_Start           = 2  // uint64
+	tagMapping_Limit           = 3  // uint64
+	tagMapping_Offset          = 4  // uint64
+	tagMapping_Filename        = 5  // int64 (string table index)
+	tagMapping_BuildID         = 6  // int64 (string table index)
+	tagMapping_HasFunctions    = 7  // bool
+	tagMapping_HasFilenames    = 8  // bool
+	tagMapping_HasLineNumbers  = 9  // bool
+	tagMapping_HasInlineFrames = 10 // bool
+
+	// message Location
+	tagLocation_ID        = 1 // uint64
+	tagLocation_MappingID = 2 // uint64
+	tagLocation_Address   = 3 // uint64
+	tagLocation_Line      = 4 // repeated Line
+
+	// message Line
+	tagLine_FunctionID = 1 // uint64
+	tagLine_Line       = 2 // int64
+
+	// message Function
+	tagFunction_ID         = 1 // uint64
+	tagFunction_Name       = 2 // int64 (string table index)
+	tagFunction_SystemName = 3 // int64 (string table index)
+	tagFunction_Filename   = 4 // int64 (string table index)
+	tagFunction_StartLine  = 5 // int64
+)
+
+// stringIndex adds s to the string table if not already present
+// and returns the index of s in the string table.
+func (b *profileBuilder) stringIndex(s string) int64 {
+	id, ok := b.stringMap[s]
+	if !ok {
+		id = len(b.strings)
+		b.strings = append(b.strings, s)
+		b.stringMap[s] = id
+	}
+	return int64(id)
+}
+
+func (b *profileBuilder) flush() {
+	const dataFlush = 4096
+	if b.pb.nest == 0 && len(b.pb.data) > dataFlush {
+		b.zw.Write(b.pb.data)
+		b.pb.data = b.pb.data[:0]
+	}
+}
+
+// pbValueType encodes a ValueType message to b.pb.
+func (b *profileBuilder) pbValueType(tag int, typ, unit string) {
+	start := b.pb.startMessage()
+	b.pb.int64(tagValueType_Type, b.stringIndex(typ))
+	b.pb.int64(tagValueType_Unit, b.stringIndex(unit))
+	b.pb.endMessage(tag, start)
+}
+
+// pbSample encodes a Sample message to b.pb.
+func (b *profileBuilder) pbSample(values []int64, locs []uint64, labels func()) {
+	start := b.pb.startMessage()
+	b.pb.int64s(tagSample_Value, values)
+	b.pb.uint64s(tagSample_Location, locs)
+	if labels != nil {
+		labels()
+	}
+	b.pb.endMessage(tagProfile_Sample, start)
+	b.flush()
+}
+
+// pbLabel encodes a Label message to b.pb.
+func (b *profileBuilder) pbLabel(tag int, key, str string, num int64) {
+	start := b.pb.startMessage()
+	b.pb.int64Opt(tagLabel_Key, b.stringIndex(key))
+	b.pb.int64Opt(tagLabel_Str, b.stringIndex(str))
+	b.pb.int64Opt(tagLabel_Num, num)
+	b.pb.endMessage(tag, start)
+}
+
+// pbLine encodes a Line message to b.pb.
+func (b *profileBuilder) pbLine(tag int, funcID uint64, line int64) {
+	start := b.pb.startMessage()
+	b.pb.uint64Opt(tagLine_FunctionID, funcID)
+	b.pb.int64Opt(tagLine_Line, line)
+	b.pb.endMessage(tag, start)
+}
+
+// pbMapping encodes a Mapping message to b.pb.
+func (b *profileBuilder) pbMapping(tag int, id, base, limit, offset uint64, file, buildID string) {
+	start := b.pb.startMessage()
+	b.pb.uint64Opt(tagMapping_ID, id)
+	b.pb.uint64Opt(tagMapping_Start, base)
+	b.pb.uint64Opt(tagMapping_Limit, limit)
+	b.pb.uint64Opt(tagMapping_Offset, offset)
+	b.pb.int64Opt(tagMapping_Filename, b.stringIndex(file))
+	b.pb.int64Opt(tagMapping_BuildID, b.stringIndex(buildID))
+	// TODO: Set any of HasInlineFrames, HasFunctions, HasFilenames, HasLineNumbers?
+	// It seems like they should all be true, but they've never been set.
+	b.pb.endMessage(tag, start)
+}
+
+// locForPC returns the location ID for addr.
+// addr must be a return PC. This returns the location of the call.
+// It may emit to b.pb, so there must be no message encoding in progress.
+func (b *profileBuilder) locForPC(addr uintptr) uint64 {
+	id := uint64(b.locs[addr])
+	if id != 0 {
+		return id
+	}
+
+	// Expand this one address using CallersFrames so we can cache
+	// each expansion. In general, CallersFrames takes a whole
+	// stack, but in this case we know there will be no skips in
+	// the stack and we have return PCs anyway.
+	frames := runtime.CallersFrames([]uintptr{addr})
+	frame, more := frames.Next()
+	if frame.Function == "runtime.goexit" {
+		// Short-circuit if we see runtime.goexit so the loop
+		// below doesn't allocate a useless empty location.
+		return 0
+	}
+
+	if frame.PC == 0 {
+		// If we failed to resolve the frame, at least make up
+		// a reasonable call PC. This mostly happens in tests.
+		frame.PC = addr - 1
+	}
+
+	// We can't write out functions while in the middle of the
+	// Location message, so record new functions we encounter and
+	// write them out after the Location.
+	type newFunc struct {
+		id         uint64
+		name, file string
+	}
+	newFuncs := make([]newFunc, 0, 8)
+
+	id = uint64(len(b.locs)) + 1
+	b.locs[addr] = int(id)
+	start := b.pb.startMessage()
+	b.pb.uint64Opt(tagLocation_ID, id)
+	b.pb.uint64Opt(tagLocation_Address, uint64(frame.PC))
+	for frame.Function != "runtime.goexit" {
+		// Write out each line in frame expansion.
+		funcID := uint64(b.funcs[frame.Function])
+		if funcID == 0 {
+			funcID = uint64(len(b.funcs)) + 1
+			b.funcs[frame.Function] = int(funcID)
+			newFuncs = append(newFuncs, newFunc{funcID, frame.Function, frame.File})
+		}
+		b.pbLine(tagLocation_Line, funcID, int64(frame.Line))
+		if !more {
+			break
+		}
+		frame, more = frames.Next()
+	}
+	if len(b.mem) > 0 {
+		i := sort.Search(len(b.mem), func(i int) bool {
+			return b.mem[i].end > addr
+		})
+		if i < len(b.mem) && b.mem[i].start <= addr && addr < b.mem[i].end {
+			b.pb.uint64Opt(tagLocation_MappingID, uint64(i+1))
+		}
+	}
+	b.pb.endMessage(tagProfile_Location, start)
+
+	// Write out functions we found during frame expansion.
+	for _, fn := range newFuncs {
+		start := b.pb.startMessage()
+		b.pb.uint64Opt(tagFunction_ID, fn.id)
+		b.pb.int64Opt(tagFunction_Name, b.stringIndex(fn.name))
+		b.pb.int64Opt(tagFunction_SystemName, b.stringIndex(fn.name))
+		b.pb.int64Opt(tagFunction_Filename, b.stringIndex(fn.file))
+		b.pb.endMessage(tagProfile_Function, start)
+	}
+
+	b.flush()
+	return id
+}
+
+// newProfileBuilder returns a new profileBuilder.
+// CPU profiling data obtained from the runtime can be added
+// by calling b.addCPUData, and then the eventual profile
+// can be obtained by calling b.finish.
+func newProfileBuilder(w io.Writer) *profileBuilder {
+	zw, _ := gzip.NewWriterLevel(w, gzip.BestSpeed)
+	b := &profileBuilder{
+		w:         w,
+		zw:        zw,
+		start:     time.Now(),
+		strings:   []string{""},
+		stringMap: map[string]int{"": 0},
+		locs:      map[uintptr]int{},
+		funcs:     map[string]int{},
+	}
+	b.readMapping()
+	return b
+}
+
+// addCPUData adds the CPU profiling data to the profile.
+// The data must be a whole number of records,
+// as delivered by the runtime.
+func (b *profileBuilder) addCPUData(data []uint64, tags []unsafe.Pointer) error {
+	if !b.havePeriod {
+		// first record is period
+		if len(data) < 3 {
+			return fmt.Errorf("truncated profile")
+		}
+		if data[0] != 3 || data[2] == 0 {
+			return fmt.Errorf("malformed profile")
+		}
+		// data[2] is sampling rate in Hz. Convert to sampling
+		// period in nanoseconds.
+		b.period = 1e9 / int64(data[2])
+		b.havePeriod = true
+		data = data[3:]
+	}
+
+	// Parse CPU samples from the profile.
+	// Each sample is 3+n uint64s:
+	//	data[0] = 3+n
+	//	data[1] = time stamp (ignored)
+	//	data[2] = count
+	//	data[3:3+n] = stack
+	// If the count is 0 and the stack has length 1,
+	// that's an overflow record inserted by the runtime
+	// to indicate that stack[0] samples were lost.
+	// Otherwise the count is usually 1,
+	// but in a few special cases like lost non-Go samples
+	// there can be larger counts.
+	// Because many samples with the same stack arrive,
+	// we want to deduplicate immediately, which we do
+	// using the b.m profMap.
+	for len(data) > 0 {
+		if len(data) < 3 || data[0] > uint64(len(data)) {
+			return fmt.Errorf("truncated profile")
+		}
+		if data[0] < 3 || tags != nil && len(tags) < 1 {
+			return fmt.Errorf("malformed profile")
+		}
+		count := data[2]
+		stk := data[3:data[0]]
+		data = data[data[0]:]
+		var tag unsafe.Pointer
+		if tags != nil {
+			tag = tags[0]
+			tags = tags[1:]
+		}
+
+		if count == 0 && len(stk) == 1 {
+			// overflow record
+			count = uint64(stk[0])
+			stk = []uint64{
+				uint64(funcPC(lostProfileEvent)),
+			}
+		}
+		b.m.lookup(stk, tag).count += int64(count)
+	}
+	return nil
+}
+
+// build completes and returns the constructed profile.
+func (b *profileBuilder) build() error {
+	b.end = time.Now()
+
+	b.pb.int64Opt(tagProfile_TimeNanos, b.start.UnixNano())
+	if b.havePeriod { // must be CPU profile
+		b.pbValueType(tagProfile_SampleType, "samples", "count")
+		b.pbValueType(tagProfile_SampleType, "cpu", "nanoseconds")
+		b.pb.int64Opt(tagProfile_DurationNanos, b.end.Sub(b.start).Nanoseconds())
+		b.pbValueType(tagProfile_PeriodType, "cpu", "nanoseconds")
+		b.pb.int64Opt(tagProfile_Period, b.period)
+	}
+
+	values := []int64{0, 0}
+	var locs []uint64
+	for e := b.m.all; e != nil; e = e.nextAll {
+		values[0] = e.count
+		values[1] = e.count * b.period
+
+		var labels func()
+		if e.tag != nil {
+			labels = func() {
+				for k, v := range *(*labelMap)(e.tag) {
+					b.pbLabel(tagSample_Label, k, v, 0)
+				}
+			}
+		}
+
+		locs = locs[:0]
+		for i, addr := range e.stk {
+			// Addresses from stack traces point to the
+			// next instruction after each call, except
+			// for the leaf, which points to where the
+			// signal occurred. locForPC expects return
+			// PCs, so increment the leaf address to look
+			// like a return PC.
+			if i == 0 {
+				addr++
+			}
+			l := b.locForPC(addr)
+			if l == 0 { // runtime.goexit
+				continue
+			}
+			locs = append(locs, l)
+		}
+		b.pbSample(values, locs, labels)
+	}
+
+	// TODO: Anything for tagProfile_DropFrames?
+	// TODO: Anything for tagProfile_KeepFrames?
+
+	b.pb.strings(tagProfile_StringTable, b.strings)
+	b.zw.Write(b.pb.data)
+	b.zw.Close()
+	return nil
+}
+
+// readMapping reads /proc/self/maps and writes mappings to b.pb.
+// It saves the address ranges of the mappings in b.mem for use
+// when emitting locations.
+func (b *profileBuilder) readMapping() {
+	data, _ := ioutil.ReadFile("/proc/self/maps")
+	parseProcSelfMaps(data, b.addMapping)
+}
+
+func parseProcSelfMaps(data []byte, addMapping func(lo, hi, offset uint64, file, buildID string)) {
+	// $ cat /proc/self/maps
+	// 00400000-0040b000 r-xp 00000000 fc:01 787766                             /bin/cat
+	// 0060a000-0060b000 r--p 0000a000 fc:01 787766                             /bin/cat
+	// 0060b000-0060c000 rw-p 0000b000 fc:01 787766                             /bin/cat
+	// 014ab000-014cc000 rw-p 00000000 00:00 0                                  [heap]
+	// 7f7d76af8000-7f7d7797c000 r--p 00000000 fc:01 1318064                    /usr/lib/locale/locale-archive
+	// 7f7d7797c000-7f7d77b36000 r-xp 00000000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+	// 7f7d77b36000-7f7d77d36000 ---p 001ba000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+	// 7f7d77d36000-7f7d77d3a000 r--p 001ba000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+	// 7f7d77d3a000-7f7d77d3c000 rw-p 001be000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+	// 7f7d77d3c000-7f7d77d41000 rw-p 00000000 00:00 0
+	// 7f7d77d41000-7f7d77d64000 r-xp 00000000 fc:01 1180217                    /lib/x86_64-linux-gnu/ld-2.19.so
+	// 7f7d77f3f000-7f7d77f42000 rw-p 00000000 00:00 0
+	// 7f7d77f61000-7f7d77f63000 rw-p 00000000 00:00 0
+	// 7f7d77f63000-7f7d77f64000 r--p 00022000 fc:01 1180217                    /lib/x86_64-linux-gnu/ld-2.19.so
+	// 7f7d77f64000-7f7d77f65000 rw-p 00023000 fc:01 1180217                    /lib/x86_64-linux-gnu/ld-2.19.so
+	// 7f7d77f65000-7f7d77f66000 rw-p 00000000 00:00 0
+	// 7ffc342a2000-7ffc342c3000 rw-p 00000000 00:00 0                          [stack]
+	// 7ffc34343000-7ffc34345000 r-xp 00000000 00:00 0                          [vdso]
+	// ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]
+
+	var line []byte
+	// next removes and returns the next field in the line.
+	// It also removes from line any spaces following the field.
+	next := func() []byte {
+		j := bytes.IndexByte(line, ' ')
+		if j < 0 {
+			f := line
+			line = nil
+			return f
+		}
+		f := line[:j]
+		line = line[j+1:]
+		for len(line) > 0 && line[0] == ' ' {
+			line = line[1:]
+		}
+		return f
+	}
+
+	for len(data) > 0 {
+		i := bytes.IndexByte(data, '\n')
+		if i < 0 {
+			line, data = data, nil
+		} else {
+			line, data = data[:i], data[i+1:]
+		}
+		addr := next()
+		i = bytes.IndexByte(addr, '-')
+		if i < 0 {
+			continue
+		}
+		lo, err := strconv.ParseUint(string(addr[:i]), 16, 64)
+		if err != nil {
+			continue
+		}
+		hi, err := strconv.ParseUint(string(addr[i+1:]), 16, 64)
+		if err != nil {
+			continue
+		}
+		perm := next()
+		if len(perm) < 4 || perm[2] != 'x' {
+			// Only interested in executable mappings.
+			continue
+		}
+		offset, err := strconv.ParseUint(string(next()), 16, 64)
+		if err != nil {
+			continue
+		}
+		next()          // dev
+		inode := next() // inode
+		if line == nil {
+			continue
+		}
+		file := string(line)
+		if len(inode) == 1 && inode[0] == '0' && file == "" {
+			// Huge-page text mappings list the initial fragment of
+			// mapped but unpopulated memory as being inode 0.
+			// Don't report that part.
+			// But [vdso] and [vsyscall] are inode 0, so let non-empty file names through.
+			continue
+		}
+
+		// TODO: pprof's remapMappingIDs makes two adjustments:
+		// 1. If there is an /anon_hugepage mapping first and it is
+		// consecutive to a next mapping, drop the /anon_hugepage.
+		// 2. If start-offset = 0x400000, change start to 0x400000 and offset to 0.
+		// There's no indication why either of these is needed.
+		// Let's try not doing these and see what breaks.
+		// If we do need them, they would go here, before we
+		// enter the mappings into b.mem in the first place.
+
+		buildID, _ := elfBuildID(file)
+		addMapping(lo, hi, offset, file, buildID)
+	}
+}
+
+func (b *profileBuilder) addMapping(lo, hi, offset uint64, file, buildID string) {
+	b.mem = append(b.mem, memMap{uintptr(lo), uintptr(hi)})
+	b.pbMapping(tagProfile_Mapping, uint64(len(b.mem)), lo, hi, offset, file, buildID)
+}
diff --git a/libgo/go/runtime/pprof/proto_test.go b/libgo/go/runtime/pprof/proto_test.go
new file mode 100644
index 0000000..a268c3a
--- /dev/null
+++ b/libgo/go/runtime/pprof/proto_test.go
@@ -0,0 +1,224 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"reflect"
+	"runtime"
+	"runtime/pprof/internal/profile"
+	"strings"
+	"testing"
+)
+
+// translateCPUProfile parses binary CPU profiling stack trace data
+// generated by runtime.CPUProfile() into a profile struct.
+// This is only used for testing. Real conversions stream the
+// data into the profileBuilder as it becomes available.
+func translateCPUProfile(data []uint64) (*profile.Profile, error) {
+	var buf bytes.Buffer
+	b := newProfileBuilder(&buf)
+	if err := b.addCPUData(data, nil); err != nil {
+		return nil, err
+	}
+	b.build()
+	return profile.Parse(&buf)
+}
+
+// fmtJSON returns a pretty-printed JSON form for x.
+// It works reasonbly well for printing protocol-buffer
+// data structures like profile.Profile.
+func fmtJSON(x interface{}) string {
+	js, _ := json.MarshalIndent(x, "", "\t")
+	return string(js)
+}
+
+func TestConvertCPUProfileEmpty(t *testing.T) {
+	// A test server with mock cpu profile data.
+	var buf bytes.Buffer
+
+	b := []uint64{3, 0, 500} // empty profile at 500 Hz (2ms sample period)
+	p, err := translateCPUProfile(b)
+	if err != nil {
+		t.Fatalf("translateCPUProfile: %v", err)
+	}
+	if err := p.Write(&buf); err != nil {
+		t.Fatalf("writing profile: %v", err)
+	}
+
+	p, err = profile.Parse(&buf)
+	if err != nil {
+		t.Fatalf("profile.Parse: %v", err)
+	}
+
+	// Expected PeriodType and SampleType.
+	periodType := &profile.ValueType{Type: "cpu", Unit: "nanoseconds"}
+	sampleType := []*profile.ValueType{
+		{Type: "samples", Unit: "count"},
+		{Type: "cpu", Unit: "nanoseconds"},
+	}
+
+	checkProfile(t, p, 2000*1000, periodType, sampleType, nil)
+}
+
+// For gccgo make these functions different so that gccgo doesn't
+// merge them with each other and with lostProfileEvent.
+func f1(i int) { f1(i + 1) }
+func f2(i int) { f2(i + 2) }
+
+// testPCs returns two PCs and two corresponding memory mappings
+// to use in test profiles.
+func testPCs(t *testing.T) (addr1, addr2 uint64, map1, map2 *profile.Mapping) {
+	switch runtime.GOOS {
+	case "linux", "android", "netbsd":
+		// Figure out two addresses from /proc/self/maps.
+		mmap, err := ioutil.ReadFile("/proc/self/maps")
+		if err != nil {
+			t.Fatal(err)
+		}
+		mprof := &profile.Profile{}
+		if err = mprof.ParseMemoryMap(bytes.NewReader(mmap)); err != nil {
+			t.Fatalf("parsing /proc/self/maps: %v", err)
+		}
+		if len(mprof.Mapping) < 2 {
+			// It is possible for a binary to only have 1 executable
+			// region of memory.
+			t.Skipf("need 2 or more mappings, got %v", len(mprof.Mapping))
+		}
+		addr1 = mprof.Mapping[0].Start
+		map1 = mprof.Mapping[0]
+		map1.BuildID, _ = elfBuildID(map1.File)
+		addr2 = mprof.Mapping[1].Start
+		map2 = mprof.Mapping[1]
+		map2.BuildID, _ = elfBuildID(map2.File)
+	default:
+		addr1 = uint64(funcPC(f1))
+		addr2 = uint64(funcPC(f2))
+	}
+	return
+}
+
+func TestConvertCPUProfile(t *testing.T) {
+	addr1, addr2, map1, map2 := testPCs(t)
+
+	b := []uint64{
+		3, 0, 500, // hz = 500
+		5, 0, 10, uint64(addr1), uint64(addr1 + 2), // 10 samples in addr1
+		5, 0, 40, uint64(addr2), uint64(addr2 + 2), // 40 samples in addr2
+		5, 0, 10, uint64(addr1), uint64(addr1 + 2), // 10 samples in addr1
+	}
+	p, err := translateCPUProfile(b)
+	if err != nil {
+		t.Fatalf("translating profile: %v", err)
+	}
+	period := int64(2000 * 1000)
+	periodType := &profile.ValueType{Type: "cpu", Unit: "nanoseconds"}
+	sampleType := []*profile.ValueType{
+		{Type: "samples", Unit: "count"},
+		{Type: "cpu", Unit: "nanoseconds"},
+	}
+	samples := []*profile.Sample{
+		{Value: []int64{20, 20 * 2000 * 1000}, Location: []*profile.Location{
+			{ID: 1, Mapping: map1, Address: addr1},
+			{ID: 2, Mapping: map1, Address: addr1 + 1},
+		}},
+		{Value: []int64{40, 40 * 2000 * 1000}, Location: []*profile.Location{
+			{ID: 3, Mapping: map2, Address: addr2},
+			{ID: 4, Mapping: map2, Address: addr2 + 1},
+		}},
+	}
+	checkProfile(t, p, period, periodType, sampleType, samples)
+}
+
+func checkProfile(t *testing.T, p *profile.Profile, period int64, periodType *profile.ValueType, sampleType []*profile.ValueType, samples []*profile.Sample) {
+	if p.Period != period {
+		t.Fatalf("p.Period = %d, want %d", p.Period, period)
+	}
+	if !reflect.DeepEqual(p.PeriodType, periodType) {
+		t.Fatalf("p.PeriodType = %v\nwant = %v", fmtJSON(p.PeriodType), fmtJSON(periodType))
+	}
+	if !reflect.DeepEqual(p.SampleType, sampleType) {
+		t.Fatalf("p.SampleType = %v\nwant = %v", fmtJSON(p.SampleType), fmtJSON(sampleType))
+	}
+	// Clear line info since it is not in the expected samples.
+	// If we used f1 and f2 above, then the samples will have line info.
+	for _, s := range p.Sample {
+		for _, l := range s.Location {
+			l.Line = nil
+		}
+	}
+	if fmtJSON(p.Sample) != fmtJSON(samples) { // ignore unexported fields
+		if len(p.Sample) == len(samples) {
+			for i := range p.Sample {
+				if !reflect.DeepEqual(p.Sample[i], samples[i]) {
+					t.Errorf("sample %d = %v\nwant = %v\n", i, fmtJSON(p.Sample[i]), fmtJSON(samples[i]))
+				}
+			}
+			if t.Failed() {
+				t.FailNow()
+			}
+		}
+		t.Fatalf("p.Sample = %v\nwant = %v", fmtJSON(p.Sample), fmtJSON(samples))
+	}
+}
+
+var profSelfMapsTests = `
+00400000-0040b000 r-xp 00000000 fc:01 787766                             /bin/cat
+0060a000-0060b000 r--p 0000a000 fc:01 787766                             /bin/cat
+0060b000-0060c000 rw-p 0000b000 fc:01 787766                             /bin/cat
+014ab000-014cc000 rw-p 00000000 00:00 0                                  [heap]
+7f7d76af8000-7f7d7797c000 r--p 00000000 fc:01 1318064                    /usr/lib/locale/locale-archive
+7f7d7797c000-7f7d77b36000 r-xp 00000000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+7f7d77b36000-7f7d77d36000 ---p 001ba000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+7f7d77d36000-7f7d77d3a000 r--p 001ba000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+7f7d77d3a000-7f7d77d3c000 rw-p 001be000 fc:01 1180226                    /lib/x86_64-linux-gnu/libc-2.19.so
+7f7d77d3c000-7f7d77d41000 rw-p 00000000 00:00 0
+7f7d77d41000-7f7d77d64000 r-xp 00000000 fc:01 1180217                    /lib/x86_64-linux-gnu/ld-2.19.so
+7f7d77f3f000-7f7d77f42000 rw-p 00000000 00:00 0
+7f7d77f61000-7f7d77f63000 rw-p 00000000 00:00 0
+7f7d77f63000-7f7d77f64000 r--p 00022000 fc:01 1180217                    /lib/x86_64-linux-gnu/ld-2.19.so
+7f7d77f64000-7f7d77f65000 rw-p 00023000 fc:01 1180217                    /lib/x86_64-linux-gnu/ld-2.19.so
+7f7d77f65000-7f7d77f66000 rw-p 00000000 00:00 0
+7ffc342a2000-7ffc342c3000 rw-p 00000000 00:00 0                          [stack]
+7ffc34343000-7ffc34345000 r-xp 00000000 00:00 0                          [vdso]
+ffffffffff600000-ffffffffff601000 r-xp 00000090 00:00 0                  [vsyscall]
+->
+00400000 0040b000 00000000 /bin/cat
+7f7d7797c000 7f7d77b36000 00000000 /lib/x86_64-linux-gnu/libc-2.19.so
+7f7d77d41000 7f7d77d64000 00000000 /lib/x86_64-linux-gnu/ld-2.19.so
+7ffc34343000 7ffc34345000 00000000 [vdso]
+ffffffffff600000 ffffffffff601000 00000090 [vsyscall]
+
+00400000-07000000 r-xp 00000000 00:00 0 
+07000000-07093000 r-xp 06c00000 00:2e 536754                             /path/to/gobench_server_main
+07093000-0722d000 rw-p 06c92000 00:2e 536754                             /path/to/gobench_server_main
+0722d000-07b21000 rw-p 00000000 00:00 0 
+c000000000-c000036000 rw-p 00000000 00:00 0 
+->
+07000000 07093000 06c00000 /path/to/gobench_server_main
+`
+
+func TestProcSelfMaps(t *testing.T) {
+	for tx, tt := range strings.Split(profSelfMapsTests, "\n\n") {
+		i := strings.Index(tt, "->\n")
+		if i < 0 {
+			t.Fatal("malformed test case")
+		}
+		in, out := tt[:i], tt[i+len("->\n"):]
+		if len(out) > 0 && out[len(out)-1] != '\n' {
+			out += "\n"
+		}
+		var buf bytes.Buffer
+		parseProcSelfMaps([]byte(in), func(lo, hi, offset uint64, file, buildID string) {
+			fmt.Fprintf(&buf, "%08x %08x %08x %s\n", lo, hi, offset, file)
+		})
+		if buf.String() != out {
+			t.Errorf("#%d: have:\n%s\nwant:\n%s\n%q\n%q", tx, buf.String(), out, buf.String(), out)
+		}
+	}
+}
diff --git a/libgo/go/runtime/pprof/protobuf.go b/libgo/go/runtime/pprof/protobuf.go
new file mode 100644
index 0000000..7b99095
--- /dev/null
+++ b/libgo/go/runtime/pprof/protobuf.go
@@ -0,0 +1,141 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+// A protobuf is a simple protocol buffer encoder.
+type protobuf struct {
+	data []byte
+	tmp  [16]byte
+	nest int
+}
+
+func (b *protobuf) varint(x uint64) {
+	for x >= 128 {
+		b.data = append(b.data, byte(x)|0x80)
+		x >>= 7
+	}
+	b.data = append(b.data, byte(x))
+}
+
+func (b *protobuf) length(tag int, len int) {
+	b.varint(uint64(tag)<<3 | 2)
+	b.varint(uint64(len))
+}
+
+func (b *protobuf) uint64(tag int, x uint64) {
+	// append varint to b.data
+	b.varint(uint64(tag)<<3 | 0)
+	b.varint(x)
+}
+
+func (b *protobuf) uint64s(tag int, x []uint64) {
+	if len(x) > 2 {
+		// Use packed encoding
+		n1 := len(b.data)
+		for _, u := range x {
+			b.varint(u)
+		}
+		n2 := len(b.data)
+		b.length(tag, n2-n1)
+		n3 := len(b.data)
+		copy(b.tmp[:], b.data[n2:n3])
+		copy(b.data[n1+(n3-n2):], b.data[n1:n2])
+		copy(b.data[n1:], b.tmp[:n3-n2])
+		return
+	}
+	for _, u := range x {
+		b.uint64(tag, u)
+	}
+}
+
+func (b *protobuf) uint64Opt(tag int, x uint64) {
+	if x == 0 {
+		return
+	}
+	b.uint64(tag, x)
+}
+
+func (b *protobuf) int64(tag int, x int64) {
+	u := uint64(x)
+	b.uint64(tag, u)
+}
+
+func (b *protobuf) int64Opt(tag int, x int64) {
+	if x == 0 {
+		return
+	}
+	b.int64(tag, x)
+}
+
+func (b *protobuf) int64s(tag int, x []int64) {
+	if len(x) > 2 {
+		// Use packed encoding
+		n1 := len(b.data)
+		for _, u := range x {
+			b.varint(uint64(u))
+		}
+		n2 := len(b.data)
+		b.length(tag, n2-n1)
+		n3 := len(b.data)
+		copy(b.tmp[:], b.data[n2:n3])
+		copy(b.data[n1+(n3-n2):], b.data[n1:n2])
+		copy(b.data[n1:], b.tmp[:n3-n2])
+		return
+	}
+	for _, u := range x {
+		b.int64(tag, u)
+	}
+}
+
+func (b *protobuf) string(tag int, x string) {
+	b.length(tag, len(x))
+	b.data = append(b.data, x...)
+}
+
+func (b *protobuf) strings(tag int, x []string) {
+	for _, s := range x {
+		b.string(tag, s)
+	}
+}
+
+func (b *protobuf) stringOpt(tag int, x string) {
+	if x == "" {
+		return
+	}
+	b.string(tag, x)
+}
+
+func (b *protobuf) bool(tag int, x bool) {
+	if x {
+		b.uint64(tag, 1)
+	} else {
+		b.uint64(tag, 0)
+	}
+}
+
+func (b *protobuf) boolOpt(tag int, x bool) {
+	if x == false {
+		return
+	}
+	b.bool(tag, x)
+}
+
+type msgOffset int
+
+func (b *protobuf) startMessage() msgOffset {
+	b.nest++
+	return msgOffset(len(b.data))
+}
+
+func (b *protobuf) endMessage(tag int, start msgOffset) {
+	n1 := int(start)
+	n2 := len(b.data)
+	b.length(tag, n2-n1)
+	n3 := len(b.data)
+	copy(b.tmp[:], b.data[n2:n3])
+	copy(b.data[n1+(n3-n2):], b.data[n1:n2])
+	copy(b.data[n1:], b.tmp[:n3-n2])
+	b.nest--
+}
diff --git a/libgo/go/runtime/pprof/protomem.go b/libgo/go/runtime/pprof/protomem.go
new file mode 100644
index 0000000..2756cfd
--- /dev/null
+++ b/libgo/go/runtime/pprof/protomem.go
@@ -0,0 +1,93 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"io"
+	"math"
+	"runtime"
+	"strings"
+)
+
+// writeHeapProto writes the current heap profile in protobuf format to w.
+func writeHeapProto(w io.Writer, p []runtime.MemProfileRecord, rate int64) error {
+	b := newProfileBuilder(w)
+	b.pbValueType(tagProfile_PeriodType, "space", "bytes")
+	b.pb.int64Opt(tagProfile_Period, rate)
+	b.pbValueType(tagProfile_SampleType, "alloc_objects", "count")
+	b.pbValueType(tagProfile_SampleType, "alloc_space", "bytes")
+	b.pbValueType(tagProfile_SampleType, "inuse_objects", "count")
+	b.pbValueType(tagProfile_SampleType, "inuse_space", "bytes")
+
+	values := []int64{0, 0, 0, 0}
+	var locs []uint64
+	for _, r := range p {
+		locs = locs[:0]
+		hideRuntime := true
+		for tries := 0; tries < 2; tries++ {
+			for _, addr := range r.Stack() {
+				// For heap profiles, all stack
+				// addresses are return PCs, which is
+				// what locForPC expects.
+				if hideRuntime {
+					if f := runtime.FuncForPC(addr); f != nil && strings.HasPrefix(f.Name(), "runtime.") {
+						continue
+					}
+					// Found non-runtime. Show any runtime uses above it.
+					hideRuntime = false
+				}
+				l := b.locForPC(addr)
+				if l == 0 { // runtime.goexit
+					continue
+				}
+				locs = append(locs, l)
+			}
+			if len(locs) > 0 {
+				break
+			}
+			hideRuntime = false // try again, and show all frames
+		}
+
+		values[0], values[1] = scaleHeapSample(r.AllocObjects, r.AllocBytes, rate)
+		values[2], values[3] = scaleHeapSample(r.InUseObjects(), r.InUseBytes(), rate)
+		var blockSize int64
+		if values[0] > 0 {
+			blockSize = values[1] / values[0]
+		}
+		b.pbSample(values, locs, func() {
+			if blockSize != 0 {
+				b.pbLabel(tagSample_Label, "bytes", "", blockSize)
+			}
+		})
+	}
+	b.build()
+	return nil
+}
+
+// scaleHeapSample adjusts the data from a heap Sample to
+// account for its probability of appearing in the collected
+// data. heap profiles are a sampling of the memory allocations
+// requests in a program. We estimate the unsampled value by dividing
+// each collected sample by its probability of appearing in the
+// profile. heap profiles rely on a poisson process to determine
+// which samples to collect, based on the desired average collection
+// rate R. The probability of a sample of size S to appear in that
+// profile is 1-exp(-S/R).
+func scaleHeapSample(count, size, rate int64) (int64, int64) {
+	if count == 0 || size == 0 {
+		return 0, 0
+	}
+
+	if rate <= 1 {
+		// if rate==1 all samples were collected so no adjustment is needed.
+		// if rate<1 treat as unknown and skip scaling.
+		return count, size
+	}
+
+	avgSize := float64(size) / float64(count)
+	scale := 1 / (1 - math.Exp(-avgSize/float64(rate)))
+
+	return int64(float64(count) * scale), int64(float64(size) * scale)
+}
diff --git a/libgo/go/runtime/pprof/protomem_test.go b/libgo/go/runtime/pprof/protomem_test.go
new file mode 100644
index 0000000..1e30ed9
--- /dev/null
+++ b/libgo/go/runtime/pprof/protomem_test.go
@@ -0,0 +1,74 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"bytes"
+	"runtime"
+	"runtime/pprof/internal/profile"
+	"testing"
+)
+
+func TestConvertMemProfile(t *testing.T) {
+	addr1, addr2, map1, map2 := testPCs(t)
+
+	var buf bytes.Buffer
+	// MemProfileRecord stacks are return PCs, so add one to the
+	// addresses recorded in the "profile". The proto profile
+	// locations are call PCs, so conversion will subtract one
+	// from these and get back to addr1 and addr2.
+	a1, a2 := uintptr(addr1)+1, uintptr(addr2)+1
+	rate := int64(512 * 1024)
+	rec := []runtime.MemProfileRecord{
+		{AllocBytes: 4096, FreeBytes: 1024, AllocObjects: 4, FreeObjects: 1, Stack0: [32]uintptr{a1, a2}},
+		{AllocBytes: 512 * 1024, FreeBytes: 0, AllocObjects: 1, FreeObjects: 0, Stack0: [32]uintptr{a2 + 1, a2 + 2}},
+		{AllocBytes: 512 * 1024, FreeBytes: 512 * 1024, AllocObjects: 1, FreeObjects: 1, Stack0: [32]uintptr{a1 + 1, a1 + 2, a2 + 3}},
+	}
+
+	if err := writeHeapProto(&buf, rec, rate); err != nil {
+		t.Fatalf("writing profile: %v", err)
+	}
+
+	p, err := profile.Parse(&buf)
+	if err != nil {
+		t.Fatalf("profile.Parse: %v", err)
+	}
+
+	periodType := &profile.ValueType{Type: "space", Unit: "bytes"}
+	sampleType := []*profile.ValueType{
+		{Type: "alloc_objects", Unit: "count"},
+		{Type: "alloc_space", Unit: "bytes"},
+		{Type: "inuse_objects", Unit: "count"},
+		{Type: "inuse_space", Unit: "bytes"},
+	}
+	samples := []*profile.Sample{
+		{
+			Value: []int64{2050, 2099200, 1537, 1574400},
+			Location: []*profile.Location{
+				{ID: 1, Mapping: map1, Address: addr1},
+				{ID: 2, Mapping: map2, Address: addr2},
+			},
+			NumLabel: map[string][]int64{"bytes": {1024}},
+		},
+		{
+			Value: []int64{1, 829411, 1, 829411},
+			Location: []*profile.Location{
+				{ID: 3, Mapping: map2, Address: addr2 + 1},
+				{ID: 4, Mapping: map2, Address: addr2 + 2},
+			},
+			NumLabel: map[string][]int64{"bytes": {829411}},
+		},
+		{
+			Value: []int64{1, 829411, 0, 0},
+			Location: []*profile.Location{
+				{ID: 5, Mapping: map1, Address: addr1 + 1},
+				{ID: 6, Mapping: map1, Address: addr1 + 2},
+				{ID: 7, Mapping: map2, Address: addr2 + 3},
+			},
+			NumLabel: map[string][]int64{"bytes": {829411}},
+		},
+	}
+	checkProfile(t, p, rate, periodType, sampleType, samples)
+}
diff --git a/libgo/go/runtime/pprof/runtime.go b/libgo/go/runtime/pprof/runtime.go
new file mode 100644
index 0000000..e6aace8
--- /dev/null
+++ b/libgo/go/runtime/pprof/runtime.go
@@ -0,0 +1,36 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"context"
+	"unsafe"
+)
+
+// runtime_setProfLabel is defined in runtime/proflabel.go.
+func runtime_setProfLabel(labels unsafe.Pointer)
+
+// runtime_getProfLabel is defined in runtime/proflabel.go.
+func runtime_getProfLabel() unsafe.Pointer
+
+// SetGoroutineLabels sets the current goroutine's labels to match ctx.
+// This is a lower-level API than Do, which should be used instead when possible.
+func SetGoroutineLabels(ctx context.Context) {
+	ctxLabels, _ := ctx.Value(labelContextKey{}).(*labelMap)
+	runtime_setProfLabel(unsafe.Pointer(ctxLabels))
+}
+
+// Do calls f with a copy of the parent context with the
+// given labels added to the parent's label map.
+// Each key/value pair in labels is inserted into the label map in the
+// order provided, overriding any previous value for the same key.
+// The augmented label map will be set for the duration of the call to f
+// and restored once f returns.
+func Do(ctx context.Context, labels LabelSet, f func(context.Context)) {
+	defer SetGoroutineLabels(ctx)
+	ctx = WithLabels(ctx, labels)
+	SetGoroutineLabels(ctx)
+	f(ctx)
+}
diff --git a/libgo/go/runtime/pprof/runtime_test.go b/libgo/go/runtime/pprof/runtime_test.go
new file mode 100644
index 0000000..0dd5324
--- /dev/null
+++ b/libgo/go/runtime/pprof/runtime_test.go
@@ -0,0 +1,96 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pprof
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"testing"
+)
+
+func TestSetGoroutineLabels(t *testing.T) {
+	sync := make(chan struct{})
+
+	wantLabels := map[string]string{}
+	if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("Expected parent goroutine's profile labels to be empty before test, got %v", gotLabels)
+	}
+	go func() {
+		if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+			t.Errorf("Expected child goroutine's profile labels to be empty before test, got %v", gotLabels)
+		}
+		sync <- struct{}{}
+	}()
+	<-sync
+
+	wantLabels = map[string]string{"key": "value"}
+	ctx := WithLabels(context.Background(), Labels("key", "value"))
+	SetGoroutineLabels(ctx)
+	if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("parent goroutine's profile labels: got %v, want %v", gotLabels, wantLabels)
+	}
+	go func() {
+		if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+			t.Errorf("child goroutine's profile labels: got %v, want %v", gotLabels, wantLabels)
+		}
+		sync <- struct{}{}
+	}()
+	<-sync
+
+	wantLabels = map[string]string{}
+	ctx = context.Background()
+	SetGoroutineLabels(ctx)
+	if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("Expected parent goroutine's profile labels to be empty, got %v", gotLabels)
+	}
+	go func() {
+		if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+			t.Errorf("Expected child goroutine's profile labels to be empty, got %v", gotLabels)
+		}
+		sync <- struct{}{}
+	}()
+	<-sync
+}
+
+func TestDo(t *testing.T) {
+	wantLabels := map[string]string{}
+	if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+		t.Errorf("Expected parent goroutine's profile labels to be empty before Do, got %v", gotLabels)
+	}
+
+	Do(context.Background(), Labels("key1", "value1", "key2", "value2"), func(ctx context.Context) {
+		wantLabels := map[string]string{"key1": "value1", "key2": "value2"}
+		if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+			t.Errorf("parent goroutine's profile labels: got %v, want %v", gotLabels, wantLabels)
+		}
+
+		sync := make(chan struct{})
+		go func() {
+			wantLabels := map[string]string{"key1": "value1", "key2": "value2"}
+			if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+				t.Errorf("child goroutine's profile labels: got %v, want %v", gotLabels, wantLabels)
+			}
+			sync <- struct{}{}
+		}()
+		<-sync
+
+	})
+
+	wantLabels = map[string]string{}
+	if gotLabels := getProfLabel(); !reflect.DeepEqual(gotLabels, wantLabels) {
+		fmt.Printf("%#v", gotLabels)
+		fmt.Printf("%#v", wantLabels)
+		t.Errorf("Expected parent goroutine's profile labels to be empty after Do, got %v", gotLabels)
+	}
+}
+
+func getProfLabel() map[string]string {
+	l := (*labelMap)(runtime_getProfLabel())
+	if l == nil {
+		return map[string]string{}
+	}
+	return *l
+}
diff --git a/libgo/go/runtime/proc.go b/libgo/go/runtime/proc.go
index 6b6f9c9..345f57b 100644
--- a/libgo/go/runtime/proc.go
+++ b/libgo/go/runtime/proc.go
@@ -214,8 +214,17 @@
 	// Make racy client program work: if panicking on
 	// another goroutine at the same time as main returns,
 	// let the other goroutine finish printing the panic trace.
-	// Once it does, it will exit. See issue 3934.
-	if panicking != 0 {
+	// Once it does, it will exit. See issues 3934 and 20018.
+	if atomic.Load(&runningPanicDefers) != 0 {
+		// Running deferred functions should not take long.
+		for c := 0; c < 1000; c++ {
+			if atomic.Load(&runningPanicDefers) == 0 {
+				break
+			}
+			Gosched()
+		}
+	}
+	if atomic.Load(&panicking) != 0 {
 		gopark(nil, nil, "panicwait", traceEvGoStop, 1)
 	}
 
@@ -255,18 +264,25 @@
 		if debug.gctrace > 0 {
 			println("GC forced")
 		}
-		gcStart(gcBackgroundMode, true)
+		// Time-triggered, fully concurrent.
+		gcStart(gcBackgroundMode, gcTrigger{kind: gcTriggerTime, now: nanotime()})
 	}
 }
 
-//go:nosplit
-
 // Gosched yields the processor, allowing other goroutines to run. It does not
 // suspend the current goroutine, so execution resumes automatically.
+//go:nosplit
 func Gosched() {
 	mcall(gosched_m)
 }
 
+// goschedguarded yields the processor like gosched, but also checks
+// for forbidden states and opts out of the yield in those cases.
+//go:nosplit
+func goschedguarded() {
+	mcall(goschedguarded_m)
+}
+
 // Puts the current goroutine into a waiting state and calls unlockf.
 // If unlockf returns false, the goroutine is resumed.
 // unlockf must not access this G's stack, as it may be moved between
@@ -419,16 +435,6 @@
 	lock(&allglock)
 	allgs = append(allgs, gp)
 	allglen = uintptr(len(allgs))
-
-	// Grow GC rescan list if necessary.
-	if len(allgs) > cap(work.rescan.list) {
-		lock(&work.rescan.lock)
-		l := work.rescan.list
-		// Let append do the heavy lifting, but keep the
-		// length the same.
-		work.rescan.list = append(l[:cap(l)], 0)[:len(l)]
-		unlock(&work.rescan.lock)
-	}
 	unlock(&allglock)
 }
 
@@ -765,9 +771,8 @@
 			nextYield = nanotime() + yieldDelay/2
 		}
 	}
-	if newval == _Grunning && gp.gcscanvalid {
-		// Run queueRescan on the system stack so it has more space.
-		systemstack(func() { queueRescan(gp) })
+	if newval == _Grunning {
+		gp.gcscanvalid = false
 	}
 }
 
@@ -779,8 +784,6 @@
 	// Nothing is racing with us now, but gcscandone might be set to true left over
 	// from an earlier round of stack scanning (we scan twice per GC).
 	// We use gcscandone to record whether the scan has been done during this round.
-	// It is important that the scan happens exactly once: if called twice,
-	// the installation of stack barriers will detect the double scan and die.
 
 	gp.gcscandone = false
 
@@ -902,7 +905,7 @@
 // in panic or being exited, this may not reliably stop all
 // goroutines.
 func stopTheWorld(reason string) {
-	semacquire(&worldsema, 0)
+	semacquire(&worldsema)
 	getg().m.preemptoff = reason
 	systemstack(stopTheWorldWithSema)
 }
@@ -1129,10 +1132,10 @@
 	}
 
 	asminit()
-	minit()
 
 	// Install signal handlers; after minit so that minit can
 	// prepare the thread to be able to handle the signals.
+	// For gccgo minit was called by C code.
 	if _g_.m == &m0 {
 		// Create an extra M for callbacks on threads not created by Go.
 		if iscgo && !cgoHasExtraM {
@@ -1363,6 +1366,7 @@
 	// running at all (that is, there's no garbage collection
 	// running right now).
 	mp.needextram = mp.schedlink == 0
+	extraMCount--
 	unlockextra(mp.schedlink.ptr())
 
 	// Save and block signals before installing g.
@@ -1376,12 +1380,16 @@
 
 	// Install g (= m->curg).
 	setg(mp.curg)
-	atomic.Store(&mp.curg.atomicstatus, _Gsyscall)
-	setGContext()
 
 	// Initialize this thread to use the m.
 	asminit()
 	minit()
+
+	setGContext()
+
+	// mp.curg is now a real goroutine.
+	casgstatus(mp.curg, _Gdead, _Gsyscall)
+	atomic.Xadd(&sched.ngsys, -1)
 }
 
 var earlycgocallback = []byte("fatal error: cgo callback before cgo call\n")
@@ -1414,14 +1422,12 @@
 	// the goroutine stack ends.
 	mp, g0SP, g0SPSize := allocm(nil, nil, true)
 	gp := malg(true, false, nil, nil)
-	gp.gcscanvalid = true // fresh G, so no dequeueRescan necessary
+	gp.gcscanvalid = true
 	gp.gcscandone = true
-	gp.gcRescan = -1
-
-	// malg returns status as Gidle, change to Gdead before adding to allg
-	// where GC will see it.
-	// gccgo uses Gdead here, not Gsyscall, because the split
-	// stack context is not initialized.
+	// malg returns status as _Gidle. Change to _Gdead before
+	// adding to allg where GC can see it. We use _Gdead to hide
+	// this from tracebacks and stack scans since it isn't a
+	// "real" goroutine until needm grabs it.
 	casgstatus(gp, _Gidle, _Gdead)
 	gp.m = mp
 	mp.curg = gp
@@ -1436,9 +1442,16 @@
 	// Here we need to set the context for g0.
 	makeGContext(mp.g0, g0SP, g0SPSize)
 
+	// gp is now on the allg list, but we don't want it to be
+	// counted by gcount. It would be more "proper" to increment
+	// sched.ngfree, but that requires locking. Incrementing ngsys
+	// has the same effect.
+	atomic.Xadd(&sched.ngsys, +1)
+
 	// Add m to the extra list.
 	mnext := lockextra(true)
 	mp.schedlink.set(mnext)
+	extraMCount++
 	unlockextra(mp)
 }
 
@@ -1474,6 +1487,10 @@
 	// with no pointer manipulation.
 	mp := getg().m
 
+	// Return mp.curg to dead state.
+	casgstatus(mp.curg, _Gsyscall, _Gdead)
+	atomic.Xadd(&sched.ngsys, +1)
+
 	// Block signals before unminit.
 	// Unminit unregisters the signal handling stack (but needs g on some systems).
 	// Setg(nil) clears g, which is the signal handler's cue not to run Go handlers.
@@ -1489,6 +1506,7 @@
 	mp.curg.gcnextsp = 0
 
 	mnext := lockextra(true)
+	extraMCount++
 	mp.schedlink.set(mnext)
 
 	setg(nil)
@@ -1505,6 +1523,7 @@
 }
 
 var extram uintptr
+var extraMCount uint32 // Protected by lockextra
 var extraMWaiters uint32
 
 // lockextra locks the extra list and returns the list head.
@@ -1551,6 +1570,10 @@
 	atomic.Storeuintptr(&extram, uintptr(unsafe.Pointer(mp)))
 }
 
+// execLock serializes exec and clone to avoid bugs or unspecified behaviour
+// around exec'ing while creating/destroying threads.  See issue #19546.
+var execLock rwmutex
+
 // Create a new m. It will start off with a call to fn, or else the scheduler.
 // fn needs to be static and not a heap allocated closure.
 // May run with m.p==nil, so write barriers are not allowed.
@@ -1559,7 +1582,9 @@
 	mp, _, _ := allocm(_p_, fn, false)
 	mp.nextp.set(_p_)
 	mp.sigmask = initSigmask
+	execLock.rlock() // Prevent process clone.
 	newosproc(mp)
+	execLock.runlock()
 }
 
 // Stops execution of the current m until new work is available.
@@ -1812,7 +1837,7 @@
 	// Check whether the profiler needs to be turned on or off.
 	hz := sched.profilehz
 	if _g_.m.profilehz != hz {
-		resetcpuprofiler(hz)
+		setThreadCPUProfiler(hz)
 	}
 
 	if trace.enabled {
@@ -1850,6 +1875,9 @@
 			ready(gp, 0, true)
 		}
 	}
+	if *cgo_yield != nil {
+		asmcgocall(*cgo_yield, nil)
+	}
 
 	// local runq
 	if gp, inheritTime := runqget(_p_); gp != nil {
@@ -2007,7 +2035,7 @@
 	}
 
 	// poll network
-	if netpollinited() && atomic.Xchg64(&sched.lastpoll, 0) != 0 {
+	if netpollinited() && atomic.Load(&netpollWaiters) > 0 && atomic.Xchg64(&sched.lastpoll, 0) != 0 {
 		if _g_.m.p != 0 {
 			throw("findrunnable: netpoll with p")
 		}
@@ -2048,7 +2076,7 @@
 	if !runqempty(p) {
 		return true
 	}
-	if netpollinited() && sched.lastpoll != 0 {
+	if netpollinited() && atomic.Load(&netpollWaiters) > 0 && sched.lastpoll != 0 {
 		if gp := netpoll(false); gp != nil {
 			injectglist(gp)
 			return true
@@ -2211,7 +2239,7 @@
 	_g_ := getg()
 
 	if trace.enabled {
-		traceGoPark(_g_.m.waittraceev, _g_.m.waittraceskip, gp)
+		traceGoPark(_g_.m.waittraceev, _g_.m.waittraceskip)
 	}
 
 	casgstatus(gp, _Grunning, _Gwaiting)
@@ -2256,6 +2284,19 @@
 	goschedImpl(gp)
 }
 
+// goschedguarded is a forbidden-states-avoided version of gosched_m
+func goschedguarded_m(gp *g) {
+
+	if gp.m.locks != 0 || gp.m.mallocing != 0 || gp.m.preemptoff != "" || gp.m.p.ptr().status != _Prunning {
+		gogo(gp) // never return
+	}
+
+	if trace.enabled {
+		traceGoSched()
+	}
+	goschedImpl(gp)
+}
+
 func gopreempt_m(gp *g) {
 	if trace.enabled {
 		traceGoPreempt()
@@ -2290,10 +2331,11 @@
 	gp.writebuf = nil
 	gp.waitreason = ""
 	gp.param = nil
+	gp.labels = nil
+	gp.timer = nil
 
 	// Note that gp's stack scan is now "valid" because it has no
-	// stack. We could dequeueRescan, but that takes a lock and
-	// isn't really necessary.
+	// stack.
 	gp.gcscanvalid = true
 	dropg()
 
@@ -2641,12 +2683,12 @@
 func beforefork() {
 	gp := getg().m.curg
 
-	// Fork can hang if preempted with signals frequently enough (see issue 5517).
-	// Ensure that we stay on the same M where we disable profiling.
+	// Block signals during a fork, so that the child does not run
+	// a signal handler before exec if a signal is sent to the process
+	// group. See issue #18600.
 	gp.m.locks++
-	if gp.m.profilehz != 0 {
-		resetcpuprofiler(0)
-	}
+	msigsave(gp.m)
+	sigblock()
 }
 
 // Called from syscall package before fork.
@@ -2659,10 +2701,8 @@
 func afterfork() {
 	gp := getg().m.curg
 
-	hz := sched.profilehz
-	if hz != 0 {
-		resetcpuprofiler(hz)
-	}
+	msigrestore(gp.m.sigmask)
+
 	gp.m.locks--
 }
 
@@ -2673,6 +2713,50 @@
 	systemstack(afterfork)
 }
 
+// inForkedChild is true while manipulating signals in the child process.
+// This is used to avoid calling libc functions in case we are using vfork.
+var inForkedChild bool
+
+// Called from syscall package after fork in child.
+// It resets non-sigignored signals to the default handler, and
+// restores the signal mask in preparation for the exec.
+//
+// Because this might be called during a vfork, and therefore may be
+// temporarily sharing address space with the parent process, this must
+// not change any global variables or calling into C code that may do so.
+//
+//go:linkname syscall_runtime_AfterForkInChild syscall.runtime_AfterForkInChild
+//go:nosplit
+//go:nowritebarrierrec
+func syscall_runtime_AfterForkInChild() {
+	// It's OK to change the global variable inForkedChild here
+	// because we are going to change it back. There is no race here,
+	// because if we are sharing address space with the parent process,
+	// then the parent process can not be running concurrently.
+	inForkedChild = true
+
+	clearSignalHandlers()
+
+	// When we are the child we are the only thread running,
+	// so we know that nothing else has changed gp.m.sigmask.
+	msigrestore(getg().m.sigmask)
+
+	inForkedChild = false
+}
+
+// Called from syscall package before Exec.
+//go:linkname syscall_runtime_BeforeExec syscall.runtime_BeforeExec
+func syscall_runtime_BeforeExec() {
+	// Prevent thread creation during exec.
+	execLock.lock()
+}
+
+// Called from syscall package after Exec.
+//go:linkname syscall_runtime_AfterExec syscall.runtime_AfterExec
+func syscall_runtime_AfterExec() {
+	execLock.unlock()
+}
+
 // Create a new g running fn passing arg as the single argument.
 // Put it on the queue of g's waiting to run.
 // The compiler turns a go statement into a call to this.
@@ -2695,7 +2779,6 @@
 	if newg == nil {
 		newg = malg(true, false, &sp, &spsize)
 		casgstatus(newg, _Gidle, _Gdead)
-		newg.gcRescan = -1
 		allgadd(newg) // publishes with a g->status of Gdead so GC scanner doesn't look at uninitialized stack.
 	} else {
 		resetNewG(newg, &sp, &spsize)
@@ -2717,17 +2800,13 @@
 	newg.param = arg
 	newg.gopc = getcallerpc(unsafe.Pointer(&fn))
 	newg.startpc = fn
-	// The stack is dirty from the argument frame, so queue it for
-	// scanning. Do this before setting it to runnable so we still
-	// own the G. If we're recycling a G, it may already be on the
-	// rescan list.
-	if newg.gcRescan == -1 {
-		queueRescan(newg)
-	} else {
-		// The recycled G is already on the rescan list. Just
-		// mark the stack dirty.
-		newg.gcscanvalid = false
+	if _g_.m.curg != nil {
+		newg.labels = _g_.m.curg.labels
 	}
+	if isSystemGoroutine(newg) {
+		atomic.Xadd(&sched.ngsys, +1)
+	}
+	newg.gcscanvalid = false
 	casgstatus(newg, _Gdead, _Grunnable)
 
 	if _p_.goidcache == _p_.goidcacheend {
@@ -2926,8 +3005,7 @@
 
 func gcount() int32 {
 	n := int32(allglen) - sched.ngfree - int32(atomic.Load(&sched.ngsys))
-	for i := 0; ; i++ {
-		_p_ := allp[i]
+	for _, _p_ := range &allp {
 		if _p_ == nil {
 			break
 		}
@@ -2947,13 +3025,18 @@
 }
 
 var prof struct {
-	lock uint32
-	hz   int32
+	signalLock uint32
+	hz         int32
 }
 
-func _System()       { _System() }
-func _ExternalCode() { _ExternalCode() }
-func _GC()           { _GC() }
+func _System()                    { _System() }
+func _ExternalCode()              { _ExternalCode() }
+func _LostExternalCode()          { _LostExternalCode() }
+func _GC()                        { _GC() }
+func _LostSIGPROFDuringAtomic64() { _LostSIGPROFDuringAtomic64() }
+
+// Counts SIGPROFs received while in atomic64 critical section, on mips{,le}
+var lostAtomic64Count uint64
 
 var _SystemPC = funcPC(_System)
 var _ExternalCodePC = funcPC(_ExternalCode)
@@ -3009,14 +3092,11 @@
 	}
 
 	if prof.hz != 0 {
-		// Simple cas-lock to coordinate with setcpuprofilerate.
-		for !atomic.Cas(&prof.lock, 0, 1) {
-			osyield()
+		if (GOARCH == "mips" || GOARCH == "mipsle") && lostAtomic64Count > 0 {
+			cpuprof.addLostAtomic64(lostAtomic64Count)
+			lostAtomic64Count = 0
 		}
-		if prof.hz != 0 {
-			cpuprof.add(stk[:n])
-		}
-		atomic.Store(&prof.lock, 0)
+		cpuprof.add(gp, stk[:n])
 	}
 	getg().m.mallocing--
 }
@@ -3047,19 +3127,28 @@
 			nonprofGoStk[1] = _ExternalCodePC + sys.PCQuantum
 		}
 
-		// Simple cas-lock to coordinate with setcpuprofilerate.
-		for !atomic.Cas(&prof.lock, 0, 1) {
-			osyield()
-		}
-		if prof.hz != 0 {
-			cpuprof.addNonGo(nonprofGoStk[:n])
-		}
-		atomic.Store(&prof.lock, 0)
+		cpuprof.addNonGo(nonprofGoStk[:n])
 	}
 }
 
-// Arrange to call fn with a traceback hz times a second.
-func setcpuprofilerate_m(hz int32) {
+// sigprofNonGoPC is called when a profiling signal arrived on a
+// non-Go thread and we have a single PC value, not a stack trace.
+// g is nil, and what we can do is very limited.
+//go:nosplit
+//go:nowritebarrierrec
+func sigprofNonGoPC(pc uintptr) {
+	if prof.hz != 0 {
+		stk := []uintptr{
+			pc,
+			funcPC(_ExternalCode) + sys.PCQuantum,
+		}
+		cpuprof.addNonGo(stk)
+	}
+}
+
+// setcpuprofilerate sets the CPU profiling rate to hz times per second.
+// If hz <= 0, setcpuprofilerate turns off CPU profiling.
+func setcpuprofilerate(hz int32) {
 	// Force sane arguments.
 	if hz < 0 {
 		hz = 0
@@ -3073,20 +3162,23 @@
 	// Stop profiler on this thread so that it is safe to lock prof.
 	// if a profiling signal came in while we had prof locked,
 	// it would deadlock.
-	resetcpuprofiler(0)
+	setThreadCPUProfiler(0)
 
-	for !atomic.Cas(&prof.lock, 0, 1) {
+	for !atomic.Cas(&prof.signalLock, 0, 1) {
 		osyield()
 	}
-	prof.hz = hz
-	atomic.Store(&prof.lock, 0)
+	if prof.hz != hz {
+		setProcessCPUProfiler(hz)
+		prof.hz = hz
+	}
+	atomic.Store(&prof.signalLock, 0)
 
 	lock(&sched.lock)
 	sched.profilehz = hz
 	unlock(&sched.lock)
 
 	if hz != 0 {
-		resetcpuprofiler(hz)
+		setThreadCPUProfiler(hz)
 	}
 
 	_g_.m.locks--
@@ -3424,7 +3516,25 @@
 				if scavengelimit < forcegcperiod {
 					maxsleep = scavengelimit / 2
 				}
+				shouldRelax := true
+				if osRelaxMinNS > 0 {
+					lock(&timers.lock)
+					if timers.sleeping {
+						now := nanotime()
+						next := timers.sleepUntil
+						if next-now < osRelaxMinNS {
+							shouldRelax = false
+						}
+					}
+					unlock(&timers.lock)
+				}
+				if shouldRelax {
+					osRelax(true)
+				}
 				notetsleep(&sched.sysmonnote, maxsleep)
+				if shouldRelax {
+					osRelax(false)
+				}
 				lock(&sched.lock)
 				atomic.Store(&sched.sysmonwait, 0)
 				noteclear(&sched.sysmonnote)
@@ -3433,10 +3543,13 @@
 			}
 			unlock(&sched.lock)
 		}
+		// trigger libc interceptors if needed
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
 		// poll network if not polled for more than 10ms
 		lastpoll := int64(atomic.Load64(&sched.lastpoll))
 		now := nanotime()
-		unixnow := unixnanotime()
 		if lastpoll != 0 && lastpoll+10*1000*1000 < now {
 			atomic.Cas64(&sched.lastpoll, uint64(lastpoll), uint64(now))
 			gp := netpoll(false) // non-blocking - returns list of goroutines
@@ -3461,8 +3574,7 @@
 			idle++
 		}
 		// check if we need to force a GC
-		lastgc := int64(atomic.Load64(&memstats.last_gc))
-		if gcphase == _GCoff && lastgc != 0 && unixnow-lastgc > forcegcperiod && atomic.Load(&forcegc.idle) != 0 {
+		if t := (gcTrigger{kind: gcTriggerTime, now: now}); t.test() && atomic.Load(&forcegc.idle) != 0 {
 			lock(&forcegc.lock)
 			forcegc.idle = 0
 			forcegc.g.schedlink = 0
@@ -3482,7 +3594,7 @@
 	}
 }
 
-var pdesc [_MaxGomaxprocs]struct {
+type sysmontick struct {
 	schedtick   uint32
 	schedwhen   int64
 	syscalltick uint32
@@ -3500,7 +3612,7 @@
 		if _p_ == nil {
 			continue
 		}
-		pd := &pdesc[i]
+		pd := &_p_.sysmontick
 		s := _p_.status
 		if s == _Psyscall {
 			// Retake P from syscall if it's there for more than 1 sysmon tick (at least 20us).
@@ -3905,7 +4017,7 @@
 
 	if randomizeScheduler {
 		for i := uint32(1); i <= n; i++ {
-			j := fastrand() % (i + 1)
+			j := fastrandn(i + 1)
 			batch[i], batch[j] = batch[j], batch[i]
 		}
 	}
diff --git a/libgo/go/runtime/proc_test.go b/libgo/go/runtime/proc_test.go
index 813c929..313a961 100644
--- a/libgo/go/runtime/proc_test.go
+++ b/libgo/go/runtime/proc_test.go
@@ -53,14 +53,14 @@
 }
 
 func TestYieldProgress(t *testing.T) {
-	testYieldProgress(t, false)
+	testYieldProgress(false)
 }
 
 func TestYieldLockedProgress(t *testing.T) {
-	testYieldProgress(t, true)
+	testYieldProgress(true)
 }
 
-func testYieldProgress(t *testing.T, locked bool) {
+func testYieldProgress(locked bool) {
 	c := make(chan bool)
 	cack := make(chan bool)
 	go func() {
@@ -430,10 +430,13 @@
 	<-lightChan
 
 	// Check that hogCount and lightCount are within a factor of
-	// 2, which indicates that both pairs of goroutines handed off
-	// the P within a time-slice to their buddy.
-	if hogCount > lightCount*2 || lightCount > hogCount*2 {
-		t.Fatalf("want hogCount/lightCount in [0.5, 2]; got %d/%d = %g", hogCount, lightCount, float64(hogCount)/float64(lightCount))
+	// 5, which indicates that both pairs of goroutines handed off
+	// the P within a time-slice to their buddy. We can use a
+	// fairly large factor here to make this robust: if the
+	// scheduler isn't working right, the gap should be ~1000X.
+	const factor = 5
+	if hogCount > lightCount*factor || lightCount > hogCount*factor {
+		t.Fatalf("want hogCount/lightCount in [%v, %v]; got %d/%d = %g", 1.0/factor, factor, hogCount, lightCount, float64(hogCount)/float64(lightCount))
 	}
 }
 
diff --git a/libgo/go/runtime/profbuf.go b/libgo/go/runtime/profbuf.go
new file mode 100644
index 0000000..f40881a
--- /dev/null
+++ b/libgo/go/runtime/profbuf.go
@@ -0,0 +1,561 @@
+// Copyright 2017 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// A profBuf is a lock-free buffer for profiling events,
+// safe for concurrent use by one reader and one writer.
+// The writer may be a signal handler running without a user g.
+// The reader is assumed to be a user g.
+//
+// Each logged event corresponds to a fixed size header, a list of
+// uintptrs (typically a stack), and exactly one unsafe.Pointer tag.
+// The header and uintptrs are stored in the circular buffer data and the
+// tag is stored in a circular buffer tags, running in parallel.
+// In the circular buffer data, each event takes 2+hdrsize+len(stk)
+// words: the value 2+hdrsize+len(stk), then the time of the event, then
+// hdrsize words giving the fixed-size header, and then len(stk) words
+// for the stack.
+//
+// The current effective offsets into the tags and data circular buffers
+// for reading and writing are stored in the high 30 and low 32 bits of r and w.
+// The bottom bits of the high 32 are additional flag bits in w, unused in r.
+// "Effective" offsets means the total number of reads or writes, mod 2^length.
+// The offset in the buffer is the effective offset mod the length of the buffer.
+// To make wraparound mod 2^length match wraparound mod length of the buffer,
+// the length of the buffer must be a power of two.
+//
+// If the reader catches up to the writer, a flag passed to read controls
+// whether the read blocks until more data is available. A read returns a
+// pointer to the buffer data itself; the caller is assumed to be done with
+// that data at the next read. The read offset rNext tracks the next offset to
+// be returned by read. By definition, r ≤ rNext ≤ w (before wraparound),
+// and rNext is only used by the reader, so it can be accessed without atomics.
+//
+// If the writer gets ahead of the reader, so that the buffer fills,
+// future writes are discarded and replaced in the output stream by an
+// overflow entry, which has size 2+hdrsize+1, time set to the time of
+// the first discarded write, a header of all zeroed words, and a "stack"
+// containing one word, the number of discarded writes.
+//
+// Between the time the buffer fills and the buffer becomes empty enough
+// to hold more data, the overflow entry is stored as a pending overflow
+// entry in the fields overflow and overflowTime. The pending overflow
+// entry can be turned into a real record by either the writer or the
+// reader. If the writer is called to write a new record and finds that
+// the output buffer has room for both the pending overflow entry and the
+// new record, the writer emits the pending overflow entry and the new
+// record into the buffer. If the reader is called to read data and finds
+// that the output buffer is empty but that there is a pending overflow
+// entry, the reader will return a synthesized record for the pending
+// overflow entry.
+//
+// Only the writer can create or add to a pending overflow entry, but
+// either the reader or the writer can clear the pending overflow entry.
+// A pending overflow entry is indicated by the low 32 bits of 'overflow'
+// holding the number of discarded writes, and overflowTime holding the
+// time of the first discarded write. The high 32 bits of 'overflow'
+// increment each time the low 32 bits transition from zero to non-zero
+// or vice versa. This sequence number avoids ABA problems in the use of
+// compare-and-swap to coordinate between reader and writer.
+// The overflowTime is only written when the low 32 bits of overflow are
+// zero, that is, only when there is no pending overflow entry, in
+// preparation for creating a new one. The reader can therefore fetch and
+// clear the entry atomically using
+//
+//	for {
+//		overflow = load(&b.overflow)
+//		if uint32(overflow) == 0 {
+//			// no pending entry
+//			break
+//		}
+//		time = load(&b.overflowTime)
+//		if cas(&b.overflow, overflow, ((overflow>>32)+1)<<32) {
+//			// pending entry cleared
+//			break
+//		}
+//	}
+//	if uint32(overflow) > 0 {
+//		emit entry for uint32(overflow), time
+//	}
+//
+type profBuf struct {
+	// accessed atomically
+	r, w         profAtomic
+	overflow     uint64
+	overflowTime uint64
+	eof          uint32
+
+	// immutable (excluding slice content)
+	hdrsize uintptr
+	data    []uint64
+	tags    []unsafe.Pointer
+
+	// owned by reader
+	rNext       profIndex
+	overflowBuf []uint64 // for use by reader to return overflow record
+	wait        note
+}
+
+// A profAtomic is the atomically-accessed word holding a profIndex.
+type profAtomic uint64
+
+// A profIndex is the packet tag and data counts and flags bits, described above.
+type profIndex uint64
+
+const (
+	profReaderSleeping profIndex = 1 << 32 // reader is sleeping and must be woken up
+	profWriteExtra     profIndex = 1 << 33 // overflow or eof waiting
+)
+
+func (x *profAtomic) load() profIndex {
+	return profIndex(atomic.Load64((*uint64)(x)))
+}
+
+func (x *profAtomic) store(new profIndex) {
+	atomic.Store64((*uint64)(x), uint64(new))
+}
+
+func (x *profAtomic) cas(old, new profIndex) bool {
+	return atomic.Cas64((*uint64)(x), uint64(old), uint64(new))
+}
+
+func (x profIndex) dataCount() uint32 {
+	return uint32(x)
+}
+
+func (x profIndex) tagCount() uint32 {
+	return uint32(x >> 34)
+}
+
+// countSub subtracts two counts obtained from profIndex.dataCount or profIndex.tagCount,
+// assuming that they are no more than 2^29 apart (guaranteed since they are never more than
+// len(data) or len(tags) apart, respectively).
+// tagCount wraps at 2^30, while dataCount wraps at 2^32.
+// This function works for both.
+func countSub(x, y uint32) int {
+	// x-y is 32-bit signed or 30-bit signed; sign-extend to 32 bits and convert to int.
+	return int(int32(x-y) << 2 >> 2)
+}
+
+// addCountsAndClearFlags returns the packed form of "x + (data, tag) - all flags".
+func (x profIndex) addCountsAndClearFlags(data, tag int) profIndex {
+	return profIndex((uint64(x)>>34+uint64(uint32(tag)<<2>>2))<<34 | uint64(uint32(x)+uint32(data)))
+}
+
+// hasOverflow reports whether b has any overflow records pending.
+func (b *profBuf) hasOverflow() bool {
+	return uint32(atomic.Load64(&b.overflow)) > 0
+}
+
+// takeOverflow consumes the pending overflow records, returning the overflow count
+// and the time of the first overflow.
+// When called by the reader, it is racing against incrementOverflow.
+func (b *profBuf) takeOverflow() (count uint32, time uint64) {
+	overflow := atomic.Load64(&b.overflow)
+	time = atomic.Load64(&b.overflowTime)
+	for {
+		count = uint32(overflow)
+		if count == 0 {
+			time = 0
+			break
+		}
+		// Increment generation, clear overflow count in low bits.
+		if atomic.Cas64(&b.overflow, overflow, ((overflow>>32)+1)<<32) {
+			break
+		}
+		overflow = atomic.Load64(&b.overflow)
+		time = atomic.Load64(&b.overflowTime)
+	}
+	return uint32(overflow), time
+}
+
+// incrementOverflow records a single overflow at time now.
+// It is racing against a possible takeOverflow in the reader.
+func (b *profBuf) incrementOverflow(now int64) {
+	for {
+		overflow := atomic.Load64(&b.overflow)
+
+		// Once we see b.overflow reach 0, it's stable: no one else is changing it underfoot.
+		// We need to set overflowTime if we're incrementing b.overflow from 0.
+		if uint32(overflow) == 0 {
+			// Store overflowTime first so it's always available when overflow != 0.
+			atomic.Store64(&b.overflowTime, uint64(now))
+			atomic.Store64(&b.overflow, (((overflow>>32)+1)<<32)+1)
+			break
+		}
+		// Otherwise we're racing to increment against reader
+		// who wants to set b.overflow to 0.
+		// Out of paranoia, leave 2³²-1 a sticky overflow value,
+		// to avoid wrapping around. Extremely unlikely.
+		if int32(overflow) == -1 {
+			break
+		}
+		if atomic.Cas64(&b.overflow, overflow, overflow+1) {
+			break
+		}
+	}
+}
+
+// newProfBuf returns a new profiling buffer with room for
+// a header of hdrsize words and a buffer of at least bufwords words.
+func newProfBuf(hdrsize, bufwords, tags int) *profBuf {
+	if min := 2 + hdrsize + 1; bufwords < min {
+		bufwords = min
+	}
+
+	// Buffer sizes must be power of two, so that we don't have to
+	// worry about uint32 wraparound changing the effective position
+	// within the buffers. We store 30 bits of count; limiting to 28
+	// gives us some room for intermediate calculations.
+	if bufwords >= 1<<28 || tags >= 1<<28 {
+		throw("newProfBuf: buffer too large")
+	}
+	var i int
+	for i = 1; i < bufwords; i <<= 1 {
+	}
+	bufwords = i
+	for i = 1; i < tags; i <<= 1 {
+	}
+	tags = i
+
+	b := new(profBuf)
+	b.hdrsize = uintptr(hdrsize)
+	b.data = make([]uint64, bufwords)
+	b.tags = make([]unsafe.Pointer, tags)
+	b.overflowBuf = make([]uint64, 2+b.hdrsize+1)
+	return b
+}
+
+// canWriteRecord reports whether the buffer has room
+// for a single contiguous record with a stack of length nstk.
+func (b *profBuf) canWriteRecord(nstk int) bool {
+	br := b.r.load()
+	bw := b.w.load()
+
+	// room for tag?
+	if countSub(br.tagCount(), bw.tagCount())+len(b.tags) < 1 {
+		return false
+	}
+
+	// room for data?
+	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
+	want := 2 + int(b.hdrsize) + nstk
+	i := int(bw.dataCount() % uint32(len(b.data)))
+	if i+want > len(b.data) {
+		// Can't fit in trailing fragment of slice.
+		// Skip over that and start over at beginning of slice.
+		nd -= len(b.data) - i
+	}
+	return nd >= want
+}
+
+// canWriteTwoRecords reports whether the buffer has room
+// for two records with stack lengths nstk1, nstk2, in that order.
+// Each record must be contiguous on its own, but the two
+// records need not be contiguous (one can be at the end of the buffer
+// and the other can wrap around and start at the beginning of the buffer).
+func (b *profBuf) canWriteTwoRecords(nstk1, nstk2 int) bool {
+	br := b.r.load()
+	bw := b.w.load()
+
+	// room for tag?
+	if countSub(br.tagCount(), bw.tagCount())+len(b.tags) < 2 {
+		return false
+	}
+
+	// room for data?
+	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
+
+	// first record
+	want := 2 + int(b.hdrsize) + nstk1
+	i := int(bw.dataCount() % uint32(len(b.data)))
+	if i+want > len(b.data) {
+		// Can't fit in trailing fragment of slice.
+		// Skip over that and start over at beginning of slice.
+		nd -= len(b.data) - i
+		i = 0
+	}
+	i += want
+	nd -= want
+
+	// second record
+	want = 2 + int(b.hdrsize) + nstk2
+	if i+want > len(b.data) {
+		// Can't fit in trailing fragment of slice.
+		// Skip over that and start over at beginning of slice.
+		nd -= len(b.data) - i
+		i = 0
+	}
+	return nd >= want
+}
+
+// write writes an entry to the profiling buffer b.
+// The entry begins with a fixed hdr, which must have
+// length b.hdrsize, followed by a variable-sized stack
+// and a single tag pointer *tagPtr (or nil if tagPtr is nil).
+// No write barriers allowed because this might be called from a signal handler.
+func (b *profBuf) write(tagPtr *unsafe.Pointer, now int64, hdr []uint64, stk []uintptr) {
+	if b == nil {
+		return
+	}
+	if len(hdr) > int(b.hdrsize) {
+		throw("misuse of profBuf.write")
+	}
+
+	if hasOverflow := b.hasOverflow(); hasOverflow && b.canWriteTwoRecords(1, len(stk)) {
+		// Room for both an overflow record and the one being written.
+		// Write the overflow record if the reader hasn't gotten to it yet.
+		// Only racing against reader, not other writers.
+		count, time := b.takeOverflow()
+		if count > 0 {
+			var stk [1]uintptr
+			stk[0] = uintptr(count)
+			b.write(nil, int64(time), nil, stk[:])
+		}
+	} else if hasOverflow || !b.canWriteRecord(len(stk)) {
+		// Pending overflow without room to write overflow and new records
+		// or no overflow but also no room for new record.
+		b.incrementOverflow(now)
+		b.wakeupExtra()
+		return
+	}
+
+	// There's room: write the record.
+	br := b.r.load()
+	bw := b.w.load()
+
+	// Profiling tag
+	//
+	// The tag is a pointer, but we can't run a write barrier here.
+	// We have interrupted the OS-level execution of gp, but the
+	// runtime still sees gp as executing. In effect, we are running
+	// in place of the real gp. Since gp is the only goroutine that
+	// can overwrite gp.labels, the value of gp.labels is stable during
+	// this signal handler: it will still be reachable from gp when
+	// we finish executing. If a GC is in progress right now, it must
+	// keep gp.labels alive, because gp.labels is reachable from gp.
+	// If gp were to overwrite gp.labels, the deletion barrier would
+	// still shade that pointer, which would preserve it for the
+	// in-progress GC, so all is well. Any future GC will see the
+	// value we copied when scanning b.tags (heap-allocated).
+	// We arrange that the store here is always overwriting a nil,
+	// so there is no need for a deletion barrier on b.tags[wt].
+	wt := int(bw.tagCount() % uint32(len(b.tags)))
+	if tagPtr != nil {
+		*(*uintptr)(unsafe.Pointer(&b.tags[wt])) = uintptr(unsafe.Pointer(*tagPtr))
+	}
+
+	// Main record.
+	// It has to fit in a contiguous section of the slice, so if it doesn't fit at the end,
+	// leave a rewind marker (0) and start over at the beginning of the slice.
+	wd := int(bw.dataCount() % uint32(len(b.data)))
+	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
+	skip := 0
+	if wd+2+int(b.hdrsize)+len(stk) > len(b.data) {
+		b.data[wd] = 0
+		skip = len(b.data) - wd
+		nd -= skip
+		wd = 0
+	}
+	data := b.data[wd:]
+	data[0] = uint64(2 + b.hdrsize + uintptr(len(stk))) // length
+	data[1] = uint64(now)                               // time stamp
+	// header, zero-padded
+	i := uintptr(copy(data[2:2+b.hdrsize], hdr))
+	for ; i < b.hdrsize; i++ {
+		data[2+i] = 0
+	}
+	for i, pc := range stk {
+		data[2+b.hdrsize+uintptr(i)] = uint64(pc)
+	}
+
+	for {
+		// Commit write.
+		// Racing with reader setting flag bits in b.w, to avoid lost wakeups.
+		old := b.w.load()
+		new := old.addCountsAndClearFlags(skip+2+len(stk)+int(b.hdrsize), 1)
+		if !b.w.cas(old, new) {
+			continue
+		}
+		// If there was a reader, wake it up.
+		if old&profReaderSleeping != 0 {
+			notewakeup(&b.wait)
+		}
+		break
+	}
+}
+
+// close signals that there will be no more writes on the buffer.
+// Once all the data has been read from the buffer, reads will return eof=true.
+func (b *profBuf) close() {
+	if atomic.Load(&b.eof) > 0 {
+		throw("runtime: profBuf already closed")
+	}
+	atomic.Store(&b.eof, 1)
+	b.wakeupExtra()
+}
+
+// wakeupExtra must be called after setting one of the "extra"
+// atomic fields b.overflow or b.eof.
+// It records the change in b.w and wakes up the reader if needed.
+func (b *profBuf) wakeupExtra() {
+	for {
+		old := b.w.load()
+		new := old | profWriteExtra
+		if !b.w.cas(old, new) {
+			continue
+		}
+		if old&profReaderSleeping != 0 {
+			notewakeup(&b.wait)
+		}
+		break
+	}
+}
+
+// profBufReadMode specifies whether to block when no data is available to read.
+type profBufReadMode int
+
+const (
+	profBufBlocking profBufReadMode = iota
+	profBufNonBlocking
+)
+
+var overflowTag [1]unsafe.Pointer // always nil
+
+func (b *profBuf) read(mode profBufReadMode) (data []uint64, tags []unsafe.Pointer, eof bool) {
+	if b == nil {
+		return nil, nil, true
+	}
+
+	br := b.rNext
+
+	// Commit previous read, returning that part of the ring to the writer.
+	// First clear tags that have now been read, both to avoid holding
+	// up the memory they point at for longer than necessary
+	// and so that b.write can assume it is always overwriting
+	// nil tag entries (see comment in b.write).
+	rPrev := b.r.load()
+	if rPrev != br {
+		ntag := countSub(br.tagCount(), rPrev.tagCount())
+		ti := int(rPrev.tagCount() % uint32(len(b.tags)))
+		for i := 0; i < ntag; i++ {
+			b.tags[ti] = nil
+			if ti++; ti == len(b.tags) {
+				ti = 0
+			}
+		}
+		b.r.store(br)
+	}
+
+Read:
+	bw := b.w.load()
+	numData := countSub(bw.dataCount(), br.dataCount())
+	if numData == 0 {
+		if b.hasOverflow() {
+			// No data to read, but there is overflow to report.
+			// Racing with writer flushing b.overflow into a real record.
+			count, time := b.takeOverflow()
+			if count == 0 {
+				// Lost the race, go around again.
+				goto Read
+			}
+			// Won the race, report overflow.
+			dst := b.overflowBuf
+			dst[0] = uint64(2 + b.hdrsize + 1)
+			dst[1] = uint64(time)
+			for i := uintptr(0); i < b.hdrsize; i++ {
+				dst[2+i] = 0
+			}
+			dst[2+b.hdrsize] = uint64(count)
+			return dst[:2+b.hdrsize+1], overflowTag[:1], false
+		}
+		if atomic.Load(&b.eof) > 0 {
+			// No data, no overflow, EOF set: done.
+			return nil, nil, true
+		}
+		if bw&profWriteExtra != 0 {
+			// Writer claims to have published extra information (overflow or eof).
+			// Attempt to clear notification and then check again.
+			// If we fail to clear the notification it means b.w changed,
+			// so we still need to check again.
+			b.w.cas(bw, bw&^profWriteExtra)
+			goto Read
+		}
+
+		// Nothing to read right now.
+		// Return or sleep according to mode.
+		if mode == profBufNonBlocking {
+			return nil, nil, false
+		}
+		if !b.w.cas(bw, bw|profReaderSleeping) {
+			goto Read
+		}
+		// Committed to sleeping.
+		notetsleepg(&b.wait, -1)
+		noteclear(&b.wait)
+		goto Read
+	}
+	data = b.data[br.dataCount()%uint32(len(b.data)):]
+	if len(data) > numData {
+		data = data[:numData]
+	} else {
+		numData -= len(data) // available in case of wraparound
+	}
+	skip := 0
+	if data[0] == 0 {
+		// Wraparound record. Go back to the beginning of the ring.
+		skip = len(data)
+		data = b.data
+		if len(data) > numData {
+			data = data[:numData]
+		}
+	}
+
+	ntag := countSub(bw.tagCount(), br.tagCount())
+	if ntag == 0 {
+		throw("runtime: malformed profBuf buffer - tag and data out of sync")
+	}
+	tags = b.tags[br.tagCount()%uint32(len(b.tags)):]
+	if len(tags) > ntag {
+		tags = tags[:ntag]
+	}
+
+	// Count out whole data records until either data or tags is done.
+	// They are always in sync in the buffer, but due to an end-of-slice
+	// wraparound we might need to stop early and return the rest
+	// in the next call.
+	di := 0
+	ti := 0
+	for di < len(data) && data[di] != 0 && ti < len(tags) {
+		if uintptr(di)+uintptr(data[di]) > uintptr(len(data)) {
+			throw("runtime: malformed profBuf buffer - invalid size")
+		}
+		di += int(data[di])
+		ti++
+	}
+
+	// Remember how much we returned, to commit read on next call.
+	b.rNext = br.addCountsAndClearFlags(skip+di, ti)
+
+	if raceenabled {
+		// Match racereleasemerge in runtime_setProfLabel,
+		// so that the setting of the labels in runtime_setProfLabel
+		// is treated as happening before any use of the labels
+		// by our caller. The synchronization on labelSync itself is a fiction
+		// for the race detector. The actual synchronization is handled
+		// by the fact that the signal handler only reads from the current
+		// goroutine and uses atomics to write the updated queue indices,
+		// and then the read-out from the signal handler buffer uses
+		// atomics to read those queue indices.
+		raceacquire(unsafe.Pointer(&labelSync))
+	}
+
+	return data[:di], tags[:ti], false
+}
diff --git a/libgo/go/runtime/profbuf_test.go b/libgo/go/runtime/profbuf_test.go
new file mode 100644
index 0000000..d9c5264
--- /dev/null
+++ b/libgo/go/runtime/profbuf_test.go
@@ -0,0 +1,182 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime_test
+
+import (
+	"reflect"
+	. "runtime"
+	"testing"
+	"time"
+	"unsafe"
+)
+
+func TestProfBuf(t *testing.T) {
+	const hdrSize = 2
+
+	write := func(t *testing.T, b *ProfBuf, tag unsafe.Pointer, now int64, hdr []uint64, stk []uintptr) {
+		b.Write(&tag, now, hdr, stk)
+	}
+	read := func(t *testing.T, b *ProfBuf, data []uint64, tags []unsafe.Pointer) {
+		rdata, rtags, eof := b.Read(ProfBufNonBlocking)
+		if !reflect.DeepEqual(rdata, data) || !reflect.DeepEqual(rtags, tags) {
+			t.Fatalf("unexpected profile read:\nhave data %#x\nwant data %#x\nhave tags %#x\nwant tags %#x", rdata, data, rtags, tags)
+		}
+		if eof {
+			t.Fatalf("unexpected eof")
+		}
+	}
+	readBlock := func(t *testing.T, b *ProfBuf, data []uint64, tags []unsafe.Pointer) func() {
+		c := make(chan int)
+		go func() {
+			eof := data == nil
+			rdata, rtags, reof := b.Read(ProfBufBlocking)
+			if !reflect.DeepEqual(rdata, data) || !reflect.DeepEqual(rtags, tags) || reof != eof {
+				// Errorf, not Fatalf, because called in goroutine.
+				t.Errorf("unexpected profile read:\nhave data %#x\nwant data %#x\nhave tags %#x\nwant tags %#x\nhave eof=%v, want %v", rdata, data, rtags, tags, reof, eof)
+			}
+			c <- 1
+		}()
+		time.Sleep(10 * time.Millisecond) // let goroutine run and block
+		return func() {
+			select {
+			case <-c:
+			case <-time.After(1 * time.Second):
+				t.Fatalf("timeout waiting for blocked read")
+			}
+		}
+	}
+	readEOF := func(t *testing.T, b *ProfBuf) {
+		rdata, rtags, eof := b.Read(ProfBufBlocking)
+		if rdata != nil || rtags != nil || !eof {
+			t.Errorf("unexpected profile read: %#x, %#x, eof=%v; want nil, nil, eof=true", rdata, rtags, eof)
+		}
+		rdata, rtags, eof = b.Read(ProfBufNonBlocking)
+		if rdata != nil || rtags != nil || !eof {
+			t.Errorf("unexpected profile read (non-blocking): %#x, %#x, eof=%v; want nil, nil, eof=true", rdata, rtags, eof)
+		}
+	}
+
+	myTags := make([]byte, 100)
+	t.Logf("myTags is %p", &myTags[0])
+
+	t.Run("BasicWriteRead", func(t *testing.T) {
+		b := NewProfBuf(2, 11, 1)
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+		read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])})
+		read(t, b, nil, nil) // release data returned by previous read
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		read(t, b, []uint64{8, 99, 101, 102, 201, 202, 203, 204}, []unsafe.Pointer{unsafe.Pointer(&myTags[2])})
+	})
+
+	t.Run("ReadMany", func(t *testing.T) {
+		b := NewProfBuf(2, 50, 50)
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		write(t, b, unsafe.Pointer(&myTags[1]), 500, []uint64{502, 504}, []uintptr{506})
+		read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 99, 101, 102, 201, 202, 203, 204, 5, 500, 502, 504, 506}, []unsafe.Pointer{unsafe.Pointer(&myTags[0]), unsafe.Pointer(&myTags[2]), unsafe.Pointer(&myTags[1])})
+	})
+
+	t.Run("ReadManyShortData", func(t *testing.T) {
+		b := NewProfBuf(2, 50, 50)
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 99, 101, 102, 201, 202, 203, 204}, []unsafe.Pointer{unsafe.Pointer(&myTags[0]), unsafe.Pointer(&myTags[2])})
+	})
+
+	t.Run("ReadManyShortTags", func(t *testing.T) {
+		b := NewProfBuf(2, 50, 50)
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 99, 101, 102, 201, 202, 203, 204}, []unsafe.Pointer{unsafe.Pointer(&myTags[0]), unsafe.Pointer(&myTags[2])})
+	})
+
+	t.Run("ReadAfterOverflow1", func(t *testing.T) {
+		// overflow record synthesized by write
+		b := NewProfBuf(2, 16, 5)
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})           // uses 10
+		read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])}) // reads 10 but still in use until next read
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5})                       // uses 6
+		read(t, b, []uint64{6, 1, 2, 3, 4, 5}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])})              // reads 6 but still in use until next read
+		// now 10 available
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204, 205, 206, 207, 208, 209}) // no room
+		for i := 0; i < 299; i++ {
+			write(t, b, unsafe.Pointer(&myTags[3]), int64(100+i), []uint64{101, 102}, []uintptr{201, 202, 203, 204}) // no room for overflow+this record
+		}
+		write(t, b, unsafe.Pointer(&myTags[1]), 500, []uint64{502, 504}, []uintptr{506}) // room for overflow+this record
+		read(t, b, []uint64{5, 99, 0, 0, 300, 5, 500, 502, 504, 506}, []unsafe.Pointer{nil, unsafe.Pointer(&myTags[1])})
+	})
+
+	t.Run("ReadAfterOverflow2", func(t *testing.T) {
+		// overflow record synthesized by read
+		b := NewProfBuf(2, 16, 5)
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213})
+		for i := 0; i < 299; i++ {
+			write(t, b, unsafe.Pointer(&myTags[3]), 100, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		}
+		read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])}) // reads 10 but still in use until next read
+		write(t, b, unsafe.Pointer(&myTags[1]), 500, []uint64{502, 504}, []uintptr{})                     // still overflow
+		read(t, b, []uint64{5, 99, 0, 0, 301}, []unsafe.Pointer{nil})                                     // overflow synthesized by read
+		write(t, b, unsafe.Pointer(&myTags[1]), 500, []uint64{502, 505}, []uintptr{506})                  // written
+		read(t, b, []uint64{5, 500, 502, 505, 506}, []unsafe.Pointer{unsafe.Pointer(&myTags[1])})
+	})
+
+	t.Run("ReadAtEndAfterOverflow", func(t *testing.T) {
+		b := NewProfBuf(2, 12, 5)
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		for i := 0; i < 299; i++ {
+			write(t, b, unsafe.Pointer(&myTags[3]), 100, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		}
+		read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])})
+		read(t, b, []uint64{5, 99, 0, 0, 300}, []unsafe.Pointer{nil})
+		write(t, b, unsafe.Pointer(&myTags[1]), 500, []uint64{502, 504}, []uintptr{506})
+		read(t, b, []uint64{5, 500, 502, 504, 506}, []unsafe.Pointer{unsafe.Pointer(&myTags[1])})
+	})
+
+	t.Run("BlockingWriteRead", func(t *testing.T) {
+		b := NewProfBuf(2, 11, 1)
+		wait := readBlock(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])})
+		write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+		wait()
+		wait = readBlock(t, b, []uint64{8, 99, 101, 102, 201, 202, 203, 204}, []unsafe.Pointer{unsafe.Pointer(&myTags[2])})
+		time.Sleep(10 * time.Millisecond)
+		write(t, b, unsafe.Pointer(&myTags[2]), 99, []uint64{101, 102}, []uintptr{201, 202, 203, 204})
+		wait()
+		wait = readBlock(t, b, nil, nil)
+		b.Close()
+		wait()
+		wait = readBlock(t, b, nil, nil)
+		wait()
+		readEOF(t, b)
+	})
+
+	t.Run("DataWraparound", func(t *testing.T) {
+		b := NewProfBuf(2, 16, 1024)
+		for i := 0; i < 10; i++ {
+			write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+			read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])})
+			read(t, b, nil, nil) // release data returned by previous read
+		}
+	})
+
+	t.Run("TagWraparound", func(t *testing.T) {
+		b := NewProfBuf(2, 1024, 2)
+		for i := 0; i < 10; i++ {
+			write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+			read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])})
+			read(t, b, nil, nil) // release data returned by previous read
+		}
+	})
+
+	t.Run("BothWraparound", func(t *testing.T) {
+		b := NewProfBuf(2, 16, 2)
+		for i := 0; i < 10; i++ {
+			write(t, b, unsafe.Pointer(&myTags[0]), 1, []uint64{2, 3}, []uintptr{4, 5, 6, 7, 8, 9})
+			read(t, b, []uint64{10, 1, 2, 3, 4, 5, 6, 7, 8, 9}, []unsafe.Pointer{unsafe.Pointer(&myTags[0])})
+			read(t, b, nil, nil) // release data returned by previous read
+		}
+	})
+}
diff --git a/libgo/go/runtime/proflabel.go b/libgo/go/runtime/proflabel.go
new file mode 100644
index 0000000..ff73fe4
--- /dev/null
+++ b/libgo/go/runtime/proflabel.go
@@ -0,0 +1,40 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+var labelSync uintptr
+
+//go:linkname runtime_setProfLabel runtime_pprof.runtime_setProfLabel
+func runtime_setProfLabel(labels unsafe.Pointer) {
+	// Introduce race edge for read-back via profile.
+	// This would more properly use &getg().labels as the sync address,
+	// but we do the read in a signal handler and can't call the race runtime then.
+	//
+	// This uses racereleasemerge rather than just racerelease so
+	// the acquire in profBuf.read synchronizes with *all* prior
+	// setProfLabel operations, not just the most recent one. This
+	// is important because profBuf.read will observe different
+	// labels set by different setProfLabel operations on
+	// different goroutines, so it needs to synchronize with all
+	// of them (this wouldn't be an issue if we could synchronize
+	// on &getg().labels since we would synchronize with each
+	// most-recent labels write separately.)
+	//
+	// racereleasemerge is like a full read-modify-write on
+	// labelSync, rather than just a store-release, so it carries
+	// a dependency on the previous racereleasemerge, which
+	// ultimately carries forward to the acquire in profBuf.read.
+	if raceenabled {
+		racereleasemerge(unsafe.Pointer(&labelSync))
+	}
+	getg().labels = labels
+}
+
+//go:linkname runtime_getProfLabel runtime_pprof.runtime_getProfLabel
+func runtime_getProfLabel() unsafe.Pointer {
+	return getg().labels
+}
diff --git a/libgo/go/runtime/rand_test.go b/libgo/go/runtime/rand_test.go
new file mode 100644
index 0000000..f8831b0
--- /dev/null
+++ b/libgo/go/runtime/rand_test.go
@@ -0,0 +1,45 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime_test
+
+import (
+	. "runtime"
+	"strconv"
+	"testing"
+)
+
+func BenchmarkFastrand(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			Fastrand()
+		}
+	})
+}
+
+func BenchmarkFastrandHashiter(b *testing.B) {
+	var m = make(map[int]int, 10)
+	for i := 0; i < 10; i++ {
+		m[i] = i
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			for _ = range m {
+				break
+			}
+		}
+	})
+}
+
+var sink32 uint32
+
+func BenchmarkFastrandn(b *testing.B) {
+	for n := uint32(2); n <= 5; n++ {
+		b.Run(strconv.Itoa(int(n)), func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				sink32 = Fastrandn(n)
+			}
+		})
+	}
+}
diff --git a/libgo/go/runtime/relax_stub.go b/libgo/go/runtime/relax_stub.go
new file mode 100644
index 0000000..81ed129
--- /dev/null
+++ b/libgo/go/runtime/relax_stub.go
@@ -0,0 +1,17 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !windows
+
+package runtime
+
+// osRelaxMinNS is the number of nanoseconds of idleness to tolerate
+// without performing an osRelax. Since osRelax may reduce the
+// precision of timers, this should be enough larger than the relaxed
+// timer precision to keep the timer error acceptable.
+const osRelaxMinNS = 0
+
+// osRelax is called by the scheduler when transitioning to and from
+// all Ps being idle.
+func osRelax(relax bool) {}
diff --git a/libgo/go/runtime/runtime1.go b/libgo/go/runtime/runtime1.go
index dd3f7b2..627adf7 100644
--- a/libgo/go/runtime/runtime1.go
+++ b/libgo/go/runtime/runtime1.go
@@ -47,15 +47,14 @@
 //go:nosplit
 func gotraceback() (level int32, all, crash bool) {
 	_g_ := getg()
-	all = _g_.m.throwing > 0
-	if _g_.m.traceback != 0 {
-		level = int32(_g_.m.traceback)
-		return
-	}
 	t := atomic.Load(&traceback_cache)
 	crash = t&tracebackCrash != 0
-	all = all || t&tracebackAll != 0
-	level = int32(t >> tracebackShift)
+	all = _g_.m.throwing > 0 || t&tracebackAll != 0
+	if _g_.m.traceback != 0 {
+		level = int32(_g_.m.traceback)
+	} else {
+		level = int32(t >> tracebackShift)
+	}
 	return
 }
 
@@ -330,35 +329,23 @@
 // except for "memprofilerate" since there is an
 // existing int var for that value, which may
 // already have an initial value.
-
-// For gccgo we use a named type so that the C code can see the
-// definition.
-type debugVars struct {
-	allocfreetrace    int32
-	cgocheck          int32
-	efence            int32
-	gccheckmark       int32
-	gcpacertrace      int32
-	gcshrinkstackoff  int32
-	gcstackbarrieroff int32
-	gcstackbarrierall int32
-	gcrescanstacks    int32
-	gcstoptheworld    int32
-	gctrace           int32
-	invalidptr        int32
-	sbrk              int32
-	scavenge          int32
-	scheddetail       int32
-	schedtrace        int32
-	wbshadow          int32
+var debug struct {
+	allocfreetrace   int32
+	cgocheck         int32
+	efence           int32
+	gccheckmark      int32
+	gcpacertrace     int32
+	gcshrinkstackoff int32
+	gcrescanstacks   int32
+	gcstoptheworld   int32
+	gctrace          int32
+	invalidptr       int32
+	sbrk             int32
+	scavenge         int32
+	scheddetail      int32
+	schedtrace       int32
 }
 
-var debug debugVars
-
-// For gccgo's C code.
-//extern runtime_setdebug
-func runtime_setdebug(*debugVars)
-
 var dbgvars = []dbgVar{
 	{"allocfreetrace", &debug.allocfreetrace},
 	{"cgocheck", &debug.cgocheck},
@@ -366,8 +353,6 @@
 	{"gccheckmark", &debug.gccheckmark},
 	{"gcpacertrace", &debug.gcpacertrace},
 	{"gcshrinkstackoff", &debug.gcshrinkstackoff},
-	{"gcstackbarrieroff", &debug.gcstackbarrieroff},
-	{"gcstackbarrierall", &debug.gcstackbarrierall},
 	{"gcrescanstacks", &debug.gcrescanstacks},
 	{"gcstoptheworld", &debug.gcstoptheworld},
 	{"gctrace", &debug.gctrace},
@@ -376,7 +361,6 @@
 	{"scavenge", &debug.scavenge},
 	{"scheddetail", &debug.scheddetail},
 	{"schedtrace", &debug.schedtrace},
-	{"wbshadow", &debug.wbshadow},
 }
 
 func parsedebugvars() {
@@ -430,26 +414,12 @@
 	setTraceback(gogetenv("GOTRACEBACK"))
 	traceback_env = traceback_cache
 
-	if debug.gcrescanstacks == 0 {
-		// Without rescanning, there's no need for stack
-		// barriers.
-		debug.gcstackbarrieroff = 1
-		debug.gcstackbarrierall = 0
-	}
-
-	// if debug.gcstackbarrierall > 0 {
-	// 	firstStackBarrierOffset = 0
-	// }
-
 	// For cgocheck > 1, we turn on the write barrier at all times
 	// and check all pointer writes.
 	if debug.cgocheck > 1 {
 		writeBarrier.cgo = true
 		writeBarrier.enabled = true
 	}
-
-	// Tell the C code what the value is.
-	runtime_setdebug(&debug)
 }
 
 //go:linkname setTraceback runtime_debug.SetTraceback
diff --git a/libgo/go/runtime/runtime2.go b/libgo/go/runtime/runtime2.go
index cdd3fcc..045e76f 100644
--- a/libgo/go/runtime/runtime2.go
+++ b/libgo/go/runtime/runtime2.go
@@ -254,7 +254,7 @@
 type sudog struct {
 	// The following fields are protected by the hchan.lock of the
 	// channel this sudog is blocking on. shrinkstack depends on
-	// this.
+	// this for sudogs involved in channel ops.
 
 	g          *g
 	selectdone *uint32 // CAS to 1 to win select race (may point to stack)
@@ -263,25 +263,19 @@
 	elem       unsafe.Pointer // data element (may point to stack)
 
 	// The following fields are never accessed concurrently.
-	// waitlink is only accessed by g.
+	// For channels, waitlink is only accessed by g.
+	// For semaphores, all fields (including the ones above)
+	// are only accessed when holding a semaRoot lock.
 
 	acquiretime int64
 	releasetime int64
 	ticket      uint32
-	waitlink    *sudog // g.waiting list
+	parent      *sudog // semaRoot binary tree
+	waitlink    *sudog // g.waiting list or semaRoot
+	waittail    *sudog // semaRoot
 	c           *hchan // channel
 }
 
-type gcstats struct {
-	// the struct must consist of only uint64's,
-	// because it is casted to uint64[].
-	nhandoff    uint64
-	nhandoffcnt uint64
-	nprocyield  uint64
-	nosyield    uint64
-	nsleep      uint64
-}
-
 /*
 Not used by gccgo.
 
@@ -318,12 +312,6 @@
 	lo uintptr
 	hi uintptr
 }
-
-// stkbar records the state of a G's stack barrier.
-type stkbar struct {
-	savedLRPtr uintptr // location overwritten by stack barrier PC
-	savedLRVal uintptr // value overwritten at savedLRPtr
-}
 */
 
 type g struct {
@@ -341,12 +329,9 @@
 	_panic *_panic // innermost panic - offset known to liblink
 	_defer *_defer // innermost defer
 	m      *m      // current m; offset known to arm liblink
-	// Not for gccgo: stackAlloc     uintptr // stack allocation is [stack.lo,stack.lo+stackAlloc)
 	// Not for gccgo: sched          gobuf
 	syscallsp uintptr // if status==Gsyscall, syscallsp = sched.sp to use during gc
 	syscallpc uintptr // if status==Gsyscall, syscallpc = sched.pc to use during gc
-	// Not for gccgo: stkbar         []stkbar       // stack barriers, from low to high (see top of mstkbar.go)
-	// Not for gccgo: stkbarPos      uintptr        // index of lowest stack barrier not hit
 	// Not for gccgo: stktopsp       uintptr        // expected sp at top of stack, to check in traceback
 	param        unsafe.Pointer // passed parameter on wakeup
 	atomicstatus uint32
@@ -359,7 +344,7 @@
 	paniconfault   bool     // panic (instead of crash) on unexpected fault address
 	preemptscan    bool     // preempted g does scan for gc
 	gcscandone     bool     // g has scanned stack; protected by _Gscan bit in status
-	gcscanvalid    bool     // false at start of gc cycle, true if G has not run since last scan; transition from true to false by calling queueRescan and false to true by calling dequeueRescan
+	gcscanvalid    bool     // false at start of gc cycle, true if G has not run since last scan; TODO: remove?
 	throwsplit     bool     // must not split stack
 	raceignore     int8     // ignore race detection events
 	sysblocktraced bool     // StartTrace has emitted EvGoInSyscall about this goroutine
@@ -376,17 +361,12 @@
 	startpc        uintptr // pc of goroutine function
 	// Not for gccgo: racectx        uintptr
 	waiting *sudog // sudog structures this g is waiting on (that have a valid elem ptr); in lock order
-	// Not for gccgo: cgoCtxt        []uintptr // cgo traceback context
+	// Not for gccgo: cgoCtxt        []uintptr      // cgo traceback context
+	labels unsafe.Pointer // profiler labels
+	timer  *timer         // cached timer for time.Sleep
 
 	// Per-G GC state
 
-	// gcRescan is this G's index in work.rescan.list. If this is
-	// -1, this G is not on the rescan list.
-	//
-	// If gcphase != _GCoff and this G is visible to the garbage
-	// collector, writes to this are protected by work.rescan.lock.
-	gcRescan int32
-
 	// gcAssistBytes is this G's GC assist credit in terms of
 	// bytes allocated. If this is positive, then the G has credit
 	// to allocate gcAssistBytes bytes without assisting. If this
@@ -452,6 +432,7 @@
 	inwb        bool // m is executing a write barrier
 	newSigstack bool // minit on C thread called sigaltstack
 	printlock   int8
+	incgo       bool // m is executing a cgo call
 	fastrand    uint32
 	ncgocall    uint64 // number of cgo calls in total
 	ncgo        int32  // number of cgo calls currently in progress
@@ -468,7 +449,6 @@
 	// Not for gccgo: fflag         uint32      // floating point compare flags
 	locked        uint32  // tracking for lockosthread
 	nextwaitm     uintptr // next m waiting for lock
-	gcstats       gcstats
 	needextram    bool
 	traceback     uint8
 	waitunlockf   unsafe.Pointer // todo go func(*g, unsafe.pointer) bool
@@ -505,9 +485,10 @@
 	id          int32
 	status      uint32 // one of pidle/prunning/...
 	link        puintptr
-	schedtick   uint32   // incremented on every scheduler call
-	syscalltick uint32   // incremented on every system call
-	m           muintptr // back-link to associated m (nil if idle)
+	schedtick   uint32     // incremented on every scheduler call
+	syscalltick uint32     // incremented on every system call
+	sysmontick  sysmontick // last tick observed by sysmon
+	m           muintptr   // back-link to associated m (nil if idle)
 	mcache      *mcache
 	// Not for gccgo: racectx     uintptr
 
@@ -543,6 +524,14 @@
 
 	tracebuf traceBufPtr
 
+	// traceSweep indicates the sweep events should be traced.
+	// This is used to defer the sweep start event until a span
+	// has actually been swept.
+	traceSweep bool
+	// traceSwept and traceReclaimed track the number of bytes
+	// swept and reclaimed by sweeping in the current sweep loop.
+	traceSwept, traceReclaimed uintptr
+
 	palloc persistentAlloc // per-P to avoid mutex
 
 	// Per-P GC state
@@ -563,7 +552,7 @@
 const (
 	// The max value of GOMAXPROCS.
 	// There are no fundamental restrictions on the value.
-	_MaxGomaxprocs = 1 << 8
+	_MaxGomaxprocs = 1 << 10
 )
 
 type schedt struct {
@@ -639,7 +628,6 @@
 	_SigThrow                // if signal.Notify doesn't take it, exit loudly
 	_SigPanic                // if the signal is from the kernel, panic
 	_SigDefault              // if the signal isn't explicitly requested, don't monitor it
-	_SigHandling             // our signal handler is registered
 	_SigGoExit               // cause all runtime procs to exit (only used on Plan 9).
 	_SigSetStack             // add SA_ONSTACK to libc handler
 	_SigUnblock              // unblocked in minit
@@ -753,13 +741,10 @@
 const _TracebackMaxFrames = 100
 
 var (
-	//	emptystring string
-
 	allglen    uintptr
 	allm       *m
 	allp       [_MaxGomaxprocs + 1]*p
 	gomaxprocs int32
-	panicking  uint32
 	ncpu       int32
 	forcegc    forcegcstate
 	sched      schedt
@@ -767,6 +752,8 @@
 
 	// Information about what cpu features are available.
 	// Set on startup in asm_{x86,amd64}.s.
+	// Packages outside the runtime should not use these
+	// as they are not an external api.
 	cpuid_ecx   uint32
 	support_aes bool
 
diff --git a/libgo/go/runtime/runtime_test.go b/libgo/go/runtime/runtime_test.go
index 1f403a1..b8f6ac2 100644
--- a/libgo/go/runtime/runtime_test.go
+++ b/libgo/go/runtime/runtime_test.go
@@ -50,6 +50,23 @@
 	}
 }
 
+var efaceCmp1 interface{}
+var efaceCmp2 interface{}
+
+func BenchmarkEfaceCmpDiff(b *testing.B) {
+	x := 5
+	efaceCmp1 = &x
+	y := 6
+	efaceCmp2 = &y
+	for i := 0; i < b.N; i++ {
+		for j := 0; j < 100; j++ {
+			if efaceCmp1 == efaceCmp2 {
+				b.Fatal("bad comparison")
+			}
+		}
+	}
+}
+
 func BenchmarkDefer(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		defer1()
@@ -62,7 +79,6 @@
 			panic("bad recover")
 		}
 	}(1, 2, 3)
-	return
 }
 
 func BenchmarkDefer10(b *testing.B) {
diff --git a/libgo/go/runtime/rwmutex.go b/libgo/go/runtime/rwmutex.go
new file mode 100644
index 0000000..7eeb559
--- /dev/null
+++ b/libgo/go/runtime/rwmutex.go
@@ -0,0 +1,125 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+)
+
+// This is a copy of sync/rwmutex.go rewritten to work in the runtime.
+
+// An rwmutex is a reader/writer mutual exclusion lock.
+// The lock can be held by an arbitrary number of readers or a single writer.
+// This is a variant of sync.RWMutex, for the runtime package.
+// Like mutex, rwmutex blocks the calling M.
+// It does not interact with the goroutine scheduler.
+type rwmutex struct {
+	rLock      mutex    // protects readers, readerPass, writer
+	readers    muintptr // list of pending readers
+	readerPass uint32   // number of pending readers to skip readers list
+
+	wLock  mutex    // serializes writers
+	writer muintptr // pending writer waiting for completing readers
+
+	readerCount uint32 // number of pending readers
+	readerWait  uint32 // number of departing readers
+}
+
+const rwmutexMaxReaders = 1 << 30
+
+// rlock locks rw for reading.
+func (rw *rwmutex) rlock() {
+	// The reader must not be allowed to lose its P or else other
+	// things blocking on the lock may consume all of the Ps and
+	// deadlock (issue #20903). Alternatively, we could drop the P
+	// while sleeping.
+	acquirem()
+	if int32(atomic.Xadd(&rw.readerCount, 1)) < 0 {
+		// A writer is pending. Park on the reader queue.
+		systemstack(func() {
+			lock(&rw.rLock)
+			if rw.readerPass > 0 {
+				// Writer finished.
+				rw.readerPass -= 1
+				unlock(&rw.rLock)
+			} else {
+				// Queue this reader to be woken by
+				// the writer.
+				m := getg().m
+				m.schedlink = rw.readers
+				rw.readers.set(m)
+				unlock(&rw.rLock)
+				notesleep(&m.park)
+				noteclear(&m.park)
+			}
+		})
+	}
+}
+
+// runlock undoes a single rlock call on rw.
+func (rw *rwmutex) runlock() {
+	if r := int32(atomic.Xadd(&rw.readerCount, -1)); r < 0 {
+		if r+1 == 0 || r+1 == -rwmutexMaxReaders {
+			throw("runlock of unlocked rwmutex")
+		}
+		// A writer is pending.
+		if atomic.Xadd(&rw.readerWait, -1) == 0 {
+			// The last reader unblocks the writer.
+			lock(&rw.rLock)
+			w := rw.writer.ptr()
+			if w != nil {
+				notewakeup(&w.park)
+			}
+			unlock(&rw.rLock)
+		}
+	}
+	releasem(getg().m)
+}
+
+// lock locks rw for writing.
+func (rw *rwmutex) lock() {
+	// Resolve competition with other writers and stick to our P.
+	lock(&rw.wLock)
+	m := getg().m
+	// Announce that there is a pending writer.
+	r := int32(atomic.Xadd(&rw.readerCount, -rwmutexMaxReaders)) + rwmutexMaxReaders
+	// Wait for any active readers to complete.
+	lock(&rw.rLock)
+	if r != 0 && atomic.Xadd(&rw.readerWait, r) != 0 {
+		// Wait for reader to wake us up.
+		systemstack(func() {
+			rw.writer.set(m)
+			unlock(&rw.rLock)
+			notesleep(&m.park)
+			noteclear(&m.park)
+		})
+	} else {
+		unlock(&rw.rLock)
+	}
+}
+
+// unlock unlocks rw for writing.
+func (rw *rwmutex) unlock() {
+	// Announce to readers that there is no active writer.
+	r := int32(atomic.Xadd(&rw.readerCount, rwmutexMaxReaders))
+	if r >= rwmutexMaxReaders {
+		throw("unlock of unlocked rwmutex")
+	}
+	// Unblock blocked readers.
+	lock(&rw.rLock)
+	for rw.readers.ptr() != nil {
+		reader := rw.readers.ptr()
+		rw.readers = reader.schedlink
+		reader.schedlink.set(nil)
+		notewakeup(&reader.park)
+		r -= 1
+	}
+	// If r > 0, there are pending readers that aren't on the
+	// queue. Tell them to skip waiting.
+	rw.readerPass += uint32(r)
+	unlock(&rw.rLock)
+	// Allow other writers to proceed.
+	unlock(&rw.wLock)
+}
diff --git a/libgo/go/runtime/rwmutex_test.go b/libgo/go/runtime/rwmutex_test.go
new file mode 100644
index 0000000..a69eca1
--- /dev/null
+++ b/libgo/go/runtime/rwmutex_test.go
@@ -0,0 +1,178 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// GOMAXPROCS=10 go test
+
+// This is a copy of sync/rwmutex_test.go rewritten to test the
+// runtime rwmutex.
+
+package runtime_test
+
+import (
+	"fmt"
+	. "runtime"
+	"sync/atomic"
+	"testing"
+)
+
+func parallelReader(m *RWMutex, clocked chan bool, cunlock *uint32, cdone chan bool) {
+	m.RLock()
+	clocked <- true
+	for atomic.LoadUint32(cunlock) == 0 {
+	}
+	m.RUnlock()
+	cdone <- true
+}
+
+func doTestParallelReaders(numReaders int) {
+	GOMAXPROCS(numReaders + 1)
+	var m RWMutex
+	clocked := make(chan bool, numReaders)
+	var cunlock uint32
+	cdone := make(chan bool)
+	for i := 0; i < numReaders; i++ {
+		go parallelReader(&m, clocked, &cunlock, cdone)
+	}
+	// Wait for all parallel RLock()s to succeed.
+	for i := 0; i < numReaders; i++ {
+		<-clocked
+	}
+	atomic.StoreUint32(&cunlock, 1)
+	// Wait for the goroutines to finish.
+	for i := 0; i < numReaders; i++ {
+		<-cdone
+	}
+}
+
+func TestParallelRWMutexReaders(t *testing.T) {
+	defer GOMAXPROCS(GOMAXPROCS(-1))
+	doTestParallelReaders(1)
+	doTestParallelReaders(3)
+	doTestParallelReaders(4)
+}
+
+func reader(rwm *RWMutex, num_iterations int, activity *int32, cdone chan bool) {
+	for i := 0; i < num_iterations; i++ {
+		rwm.RLock()
+		n := atomic.AddInt32(activity, 1)
+		if n < 1 || n >= 10000 {
+			panic(fmt.Sprintf("wlock(%d)\n", n))
+		}
+		for i := 0; i < 100; i++ {
+		}
+		atomic.AddInt32(activity, -1)
+		rwm.RUnlock()
+	}
+	cdone <- true
+}
+
+func writer(rwm *RWMutex, num_iterations int, activity *int32, cdone chan bool) {
+	for i := 0; i < num_iterations; i++ {
+		rwm.Lock()
+		n := atomic.AddInt32(activity, 10000)
+		if n != 10000 {
+			panic(fmt.Sprintf("wlock(%d)\n", n))
+		}
+		for i := 0; i < 100; i++ {
+		}
+		atomic.AddInt32(activity, -10000)
+		rwm.Unlock()
+	}
+	cdone <- true
+}
+
+func HammerRWMutex(gomaxprocs, numReaders, num_iterations int) {
+	GOMAXPROCS(gomaxprocs)
+	// Number of active readers + 10000 * number of active writers.
+	var activity int32
+	var rwm RWMutex
+	cdone := make(chan bool)
+	go writer(&rwm, num_iterations, &activity, cdone)
+	var i int
+	for i = 0; i < numReaders/2; i++ {
+		go reader(&rwm, num_iterations, &activity, cdone)
+	}
+	go writer(&rwm, num_iterations, &activity, cdone)
+	for ; i < numReaders; i++ {
+		go reader(&rwm, num_iterations, &activity, cdone)
+	}
+	// Wait for the 2 writers and all readers to finish.
+	for i := 0; i < 2+numReaders; i++ {
+		<-cdone
+	}
+}
+
+func TestRWMutex(t *testing.T) {
+	defer GOMAXPROCS(GOMAXPROCS(-1))
+	n := 1000
+	if testing.Short() {
+		n = 5
+	}
+	HammerRWMutex(1, 1, n)
+	HammerRWMutex(1, 3, n)
+	HammerRWMutex(1, 10, n)
+	HammerRWMutex(4, 1, n)
+	HammerRWMutex(4, 3, n)
+	HammerRWMutex(4, 10, n)
+	HammerRWMutex(10, 1, n)
+	HammerRWMutex(10, 3, n)
+	HammerRWMutex(10, 10, n)
+	HammerRWMutex(10, 5, n)
+}
+
+func BenchmarkRWMutexUncontended(b *testing.B) {
+	type PaddedRWMutex struct {
+		RWMutex
+		pad [32]uint32
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		var rwm PaddedRWMutex
+		for pb.Next() {
+			rwm.RLock()
+			rwm.RLock()
+			rwm.RUnlock()
+			rwm.RUnlock()
+			rwm.Lock()
+			rwm.Unlock()
+		}
+	})
+}
+
+func benchmarkRWMutex(b *testing.B, localWork, writeRatio int) {
+	var rwm RWMutex
+	b.RunParallel(func(pb *testing.PB) {
+		foo := 0
+		for pb.Next() {
+			foo++
+			if foo%writeRatio == 0 {
+				rwm.Lock()
+				rwm.Unlock()
+			} else {
+				rwm.RLock()
+				for i := 0; i != localWork; i += 1 {
+					foo *= 2
+					foo /= 2
+				}
+				rwm.RUnlock()
+			}
+		}
+		_ = foo
+	})
+}
+
+func BenchmarkRWMutexWrite100(b *testing.B) {
+	benchmarkRWMutex(b, 0, 100)
+}
+
+func BenchmarkRWMutexWrite10(b *testing.B) {
+	benchmarkRWMutex(b, 0, 10)
+}
+
+func BenchmarkRWMutexWorkWrite100(b *testing.B) {
+	benchmarkRWMutex(b, 100, 100)
+}
+
+func BenchmarkRWMutexWorkWrite10(b *testing.B) {
+	benchmarkRWMutex(b, 100, 10)
+}
diff --git a/libgo/go/runtime/select.go b/libgo/go/runtime/select.go
index f0cad1b..9f8ac49 100644
--- a/libgo/go/runtime/select.go
+++ b/libgo/go/runtime/select.go
@@ -98,7 +98,6 @@
 		return
 	}
 	cas := (*scase)(add(unsafe.Pointer(&sel.scase), uintptr(i)*unsafe.Sizeof(sel.scase[0])))
-
 	cas.pc = pc
 	cas.c = c
 	cas.kind = caseSend
@@ -246,7 +245,7 @@
 	pollslice := slice{unsafe.Pointer(sel.pollorder), int(sel.ncase), int(sel.ncase)}
 	pollorder := *(*[]uint16)(unsafe.Pointer(&pollslice))
 	for i := 1; i < int(sel.ncase); i++ {
-		j := int(fastrand()) % (i + 1)
+		j := fastrandn(uint32(i + 1))
 		pollorder[i] = pollorder[j]
 		pollorder[j] = uint16(i)
 	}
@@ -408,7 +407,7 @@
 
 	// wait for someone to wake us up
 	gp.param = nil
-	gopark(selparkcommit, nil, "select", traceEvGoBlockSelect, 2)
+	gopark(selparkcommit, nil, "select", traceEvGoBlockSelect, 1)
 
 	// While we were asleep, some goroutine came along and completed
 	// one of the cases in the select and woke us up (called ready).
@@ -602,7 +601,7 @@
 
 recv:
 	// can receive from sleeping sender (sg)
-	recv(c, sg, cas.elem, func() { selunlock(scases, lockorder) })
+	recv(c, sg, cas.elem, func() { selunlock(scases, lockorder) }, 2)
 	if debugSelect {
 		print("syncrecv: sel=", sel, " c=", c, "\n")
 	}
@@ -633,7 +632,7 @@
 	if msanenabled {
 		msanread(cas.elem, c.elemtype.size)
 	}
-	send(c, sg, cas.elem, func() { selunlock(scases, lockorder) })
+	send(c, sg, cas.elem, func() { selunlock(scases, lockorder) }, 2)
 	if debugSelect {
 		print("syncsend: sel=", sel, " c=", c, "\n")
 	}
@@ -641,7 +640,7 @@
 
 retc:
 	if cas.releasetime > 0 {
-		blockevent(cas.releasetime-t0, 2)
+		blockevent(cas.releasetime-t0, 1)
 	}
 	return casi
 
diff --git a/libgo/go/runtime/sema.go b/libgo/go/runtime/sema.go
index 37318ff..d04e6f5 100644
--- a/libgo/go/runtime/sema.go
+++ b/libgo/go/runtime/sema.go
@@ -27,10 +27,19 @@
 
 // Asynchronous semaphore for sync.Mutex.
 
+// A semaRoot holds a balanced tree of sudog with distinct addresses (s.elem).
+// Each of those sudog may in turn point (through s.waitlink) to a list
+// of other sudogs waiting on the same address.
+// The operations on the inner lists of sudogs with the same address
+// are all O(1). The scanning of the top-level semaRoot list is O(log n),
+// where n is the number of distinct addresses with goroutines blocked
+// on them that hash to the given semaRoot.
+// See golang.org/issue/17953 for a program that worked badly
+// before we introduced the second level of list, and test/locklinear.go
+// for a test that exercises this.
 type semaRoot struct {
 	lock  mutex
-	head  *sudog
-	tail  *sudog
+	treap *sudog // root of balanced tree of unique waiters.
 	nwait uint32 // Number of waiters. Read w/o the lock.
 }
 
@@ -44,26 +53,26 @@
 
 //go:linkname sync_runtime_Semacquire sync.runtime_Semacquire
 func sync_runtime_Semacquire(addr *uint32) {
-	semacquire(addr, semaBlockProfile)
+	semacquire1(addr, false, semaBlockProfile)
 }
 
-//go:linkname net_runtime_Semacquire net.runtime_Semacquire
-func net_runtime_Semacquire(addr *uint32) {
-	semacquire(addr, semaBlockProfile)
+//go:linkname poll_runtime_Semacquire internal_poll.runtime_Semacquire
+func poll_runtime_Semacquire(addr *uint32) {
+	semacquire1(addr, false, semaBlockProfile)
 }
 
 //go:linkname sync_runtime_Semrelease sync.runtime_Semrelease
-func sync_runtime_Semrelease(addr *uint32) {
-	semrelease(addr)
+func sync_runtime_Semrelease(addr *uint32, handoff bool) {
+	semrelease1(addr, handoff)
 }
 
 //go:linkname sync_runtime_SemacquireMutex sync.runtime_SemacquireMutex
-func sync_runtime_SemacquireMutex(addr *uint32) {
-	semacquire(addr, semaBlockProfile|semaMutexProfile)
+func sync_runtime_SemacquireMutex(addr *uint32, lifo bool) {
+	semacquire1(addr, lifo, semaBlockProfile|semaMutexProfile)
 }
 
-//go:linkname net_runtime_Semrelease net.runtime_Semrelease
-func net_runtime_Semrelease(addr *uint32) {
+//go:linkname poll_runtime_Semrelease internal_poll.runtime_Semrelease
+func poll_runtime_Semrelease(addr *uint32) {
 	semrelease(addr)
 }
 
@@ -82,7 +91,11 @@
 )
 
 // Called from runtime.
-func semacquire(addr *uint32, profile semaProfileFlags) {
+func semacquire(addr *uint32) {
+	semacquire1(addr, false, 0)
+}
+
+func semacquire1(addr *uint32, lifo bool, profile semaProfileFlags) {
 	gp := getg()
 	if gp != gp.m.curg {
 		throw("semacquire not on the G stack")
@@ -104,6 +117,7 @@
 	t0 := int64(0)
 	s.releasetime = 0
 	s.acquiretime = 0
+	s.ticket = 0
 	if profile&semaBlockProfile != 0 && blockprofilerate > 0 {
 		t0 = cputicks()
 		s.releasetime = -1
@@ -126,9 +140,9 @@
 		}
 		// Any semrelease after the cansemacquire knows we're waiting
 		// (we set nwait above), so go to sleep.
-		root.queue(addr, s)
+		root.queue(addr, s, lifo)
 		goparkunlock(&root.lock, "semacquire", traceEvGoBlockSync, 4)
-		if cansemacquire(addr) {
+		if s.ticket != 0 || cansemacquire(addr) {
 			break
 		}
 	}
@@ -139,6 +153,10 @@
 }
 
 func semrelease(addr *uint32) {
+	semrelease1(addr, false)
+}
+
+func semrelease1(addr *uint32, handoff bool) {
 	root := semroot(addr)
 	atomic.Xadd(addr, 1)
 
@@ -157,28 +175,22 @@
 		unlock(&root.lock)
 		return
 	}
-	s := root.head
-	for ; s != nil; s = s.next {
-		if s.elem == unsafe.Pointer(addr) {
-			atomic.Xadd(&root.nwait, -1)
-			root.dequeue(s)
-			break
-		}
-	}
+	s, t0 := root.dequeue(addr)
 	if s != nil {
-		if s.acquiretime != 0 {
-			t0 := cputicks()
-			for x := root.head; x != nil; x = x.next {
-				if x.elem == unsafe.Pointer(addr) {
-					x.acquiretime = t0
-					break
-				}
-			}
-			mutexevent(t0-s.acquiretime, 3)
-		}
+		atomic.Xadd(&root.nwait, -1)
 	}
 	unlock(&root.lock)
 	if s != nil { // May be slow, so unlock first
+		acquiretime := s.acquiretime
+		if acquiretime != 0 {
+			mutexevent(t0-acquiretime, 3)
+		}
+		if s.ticket != 0 {
+			throw("corrupted semaphore ticket")
+		}
+		if handoff && cansemacquire(addr) {
+			s.ticket = 1
+		}
 		readyWithTime(s, 5)
 	}
 }
@@ -199,33 +211,230 @@
 	}
 }
 
-func (root *semaRoot) queue(addr *uint32, s *sudog) {
+// queue adds s to the blocked goroutines in semaRoot.
+func (root *semaRoot) queue(addr *uint32, s *sudog, lifo bool) {
 	s.g = getg()
 	s.elem = unsafe.Pointer(addr)
 	s.next = nil
-	s.prev = root.tail
-	if root.tail != nil {
-		root.tail.next = s
-	} else {
-		root.head = s
+	s.prev = nil
+
+	var last *sudog
+	pt := &root.treap
+	for t := *pt; t != nil; t = *pt {
+		if t.elem == unsafe.Pointer(addr) {
+			// Already have addr in list.
+			if lifo {
+				// Substitute s in t's place in treap.
+				*pt = s
+				s.ticket = t.ticket
+				s.acquiretime = t.acquiretime
+				s.parent = t.parent
+				s.prev = t.prev
+				s.next = t.next
+				if s.prev != nil {
+					s.prev.parent = s
+				}
+				if s.next != nil {
+					s.next.parent = s
+				}
+				// Add t first in s's wait list.
+				s.waitlink = t
+				s.waittail = t.waittail
+				if s.waittail == nil {
+					s.waittail = t
+				}
+				t.parent = nil
+				t.prev = nil
+				t.next = nil
+				t.waittail = nil
+			} else {
+				// Add s to end of t's wait list.
+				if t.waittail == nil {
+					t.waitlink = s
+				} else {
+					t.waittail.waitlink = s
+				}
+				t.waittail = s
+				s.waitlink = nil
+			}
+			return
+		}
+		last = t
+		if uintptr(unsafe.Pointer(addr)) < uintptr(t.elem) {
+			pt = &t.prev
+		} else {
+			pt = &t.next
+		}
 	}
-	root.tail = s
+
+	// Add s as new leaf in tree of unique addrs.
+	// The balanced tree is a treap using ticket as the random heap priority.
+	// That is, it is a binary tree ordered according to the elem addresses,
+	// but then among the space of possible binary trees respecting those
+	// addresses, it is kept balanced on average by maintaining a heap ordering
+	// on the ticket: s.ticket <= both s.prev.ticket and s.next.ticket.
+	// https://en.wikipedia.org/wiki/Treap
+	// http://faculty.washington.edu/aragon/pubs/rst89.pdf
+	s.ticket = fastrand()
+	s.parent = last
+	*pt = s
+
+	// Rotate up into tree according to ticket (priority).
+	for s.parent != nil && s.parent.ticket > s.ticket {
+		if s.parent.prev == s {
+			root.rotateRight(s.parent)
+		} else {
+			if s.parent.next != s {
+				panic("semaRoot queue")
+			}
+			root.rotateLeft(s.parent)
+		}
+	}
 }
 
-func (root *semaRoot) dequeue(s *sudog) {
-	if s.next != nil {
-		s.next.prev = s.prev
-	} else {
-		root.tail = s.prev
+// dequeue searches for and finds the first goroutine
+// in semaRoot blocked on addr.
+// If the sudog was being profiled, dequeue returns the time
+// at which it was woken up as now. Otherwise now is 0.
+func (root *semaRoot) dequeue(addr *uint32) (found *sudog, now int64) {
+	ps := &root.treap
+	s := *ps
+	for ; s != nil; s = *ps {
+		if s.elem == unsafe.Pointer(addr) {
+			goto Found
+		}
+		if uintptr(unsafe.Pointer(addr)) < uintptr(s.elem) {
+			ps = &s.prev
+		} else {
+			ps = &s.next
+		}
 	}
-	if s.prev != nil {
-		s.prev.next = s.next
-	} else {
-		root.head = s.next
+	return nil, 0
+
+Found:
+	now = int64(0)
+	if s.acquiretime != 0 {
+		now = cputicks()
 	}
+	if t := s.waitlink; t != nil {
+		// Substitute t, also waiting on addr, for s in root tree of unique addrs.
+		*ps = t
+		t.ticket = s.ticket
+		t.parent = s.parent
+		t.prev = s.prev
+		if t.prev != nil {
+			t.prev.parent = t
+		}
+		t.next = s.next
+		if t.next != nil {
+			t.next.parent = t
+		}
+		if t.waitlink != nil {
+			t.waittail = s.waittail
+		} else {
+			t.waittail = nil
+		}
+		t.acquiretime = now
+		s.waitlink = nil
+		s.waittail = nil
+	} else {
+		// Rotate s down to be leaf of tree for removal, respecting priorities.
+		for s.next != nil || s.prev != nil {
+			if s.next == nil || s.prev != nil && s.prev.ticket < s.next.ticket {
+				root.rotateRight(s)
+			} else {
+				root.rotateLeft(s)
+			}
+		}
+		// Remove s, now a leaf.
+		if s.parent != nil {
+			if s.parent.prev == s {
+				s.parent.prev = nil
+			} else {
+				s.parent.next = nil
+			}
+		} else {
+			root.treap = nil
+		}
+	}
+	s.parent = nil
 	s.elem = nil
 	s.next = nil
 	s.prev = nil
+	s.ticket = 0
+	return s, now
+}
+
+// rotateLeft rotates the tree rooted at node x.
+// turning (x a (y b c)) into (y (x a b) c).
+func (root *semaRoot) rotateLeft(x *sudog) {
+	// p -> (x a (y b c))
+	p := x.parent
+	a, y := x.prev, x.next
+	b, c := y.prev, y.next
+
+	y.prev = x
+	x.parent = y
+	y.next = c
+	if c != nil {
+		c.parent = y
+	}
+	x.prev = a
+	if a != nil {
+		a.parent = x
+	}
+	x.next = b
+	if b != nil {
+		b.parent = x
+	}
+
+	y.parent = p
+	if p == nil {
+		root.treap = y
+	} else if p.prev == x {
+		p.prev = y
+	} else {
+		if p.next != x {
+			throw("semaRoot rotateLeft")
+		}
+		p.next = y
+	}
+}
+
+// rotateRight rotates the tree rooted at node y.
+// turning (y (x a b) c) into (x a (y b c)).
+func (root *semaRoot) rotateRight(y *sudog) {
+	// p -> (y (x a b) c)
+	p := y.parent
+	x, c := y.prev, y.next
+	a, b := x.prev, x.next
+
+	x.prev = a
+	if a != nil {
+		a.parent = x
+	}
+	x.next = y
+	y.parent = x
+	y.prev = b
+	if b != nil {
+		b.parent = y
+	}
+	y.next = c
+	if c != nil {
+		c.parent = y
+	}
+
+	x.parent = p
+	if p == nil {
+		root.treap = x
+	} else if p.prev == y {
+		p.prev = x
+	} else {
+		if p.next != y {
+			throw("semaRoot rotateRight")
+		}
+		p.next = x
+	}
 }
 
 // notifyList is a ticket-based notification list used to implement sync.Cond.
@@ -352,10 +561,22 @@
 		return
 	}
 
-	// Update the next notify ticket number, and try to find the G that
-	// needs to be notified. If it hasn't made it to the list yet we won't
-	// find it, but it won't park itself once it sees the new notify number.
+	// Update the next notify ticket number.
 	atomic.Store(&l.notify, t+1)
+
+	// Try to find the g that needs to be notified.
+	// If it hasn't made it to the list yet we won't find it,
+	// but it won't park itself once it sees the new notify number.
+	//
+	// This scan looks linear but essentially always stops quickly.
+	// Because g's queue separately from taking numbers,
+	// there may be minor reorderings in the list, but we
+	// expect the g we're looking for to be near the front.
+	// The g has others in front of it on the list only to the
+	// extent that it lost the race, so the iteration will not
+	// be too long. This applies even when the g is missing:
+	// it hasn't yet gotten to sleep and has lost the race to
+	// the (few) other g's that we find on the list.
 	for p, s := (*sudog)(nil), l.head; s != nil; p, s = s, s.next {
 		if s.ticket == t {
 			n := s.next
@@ -383,3 +604,8 @@
 		throw("bad notifyList size")
 	}
 }
+
+//go:linkname sync_nanotime sync.runtime_nanotime
+func sync_nanotime() int64 {
+	return nanotime()
+}
diff --git a/libgo/go/runtime/signal_sighandler.go b/libgo/go/runtime/signal_sighandler.go
index b71b21e..378c68e 100644
--- a/libgo/go/runtime/signal_sighandler.go
+++ b/libgo/go/runtime/signal_sighandler.go
@@ -111,7 +111,7 @@
 
 	if docrash {
 		crashing++
-		if crashing < sched.mcount {
+		if crashing < sched.mcount-int32(extraMCount) {
 			// There are other m's that need to dump their stacks.
 			// Relay SIGQUIT to the next m by sending it to the current process.
 			// All m's that have already received SIGQUIT have signal masks blocking
diff --git a/libgo/go/runtime/signal_unix.go b/libgo/go/runtime/signal_unix.go
index e2642ee..3237e18 100644
--- a/libgo/go/runtime/signal_unix.go
+++ b/libgo/go/runtime/signal_unix.go
@@ -7,14 +7,13 @@
 package runtime
 
 import (
+	"runtime/internal/atomic"
 	"runtime/internal/sys"
 	"unsafe"
 )
 
 // For gccgo's C code to call:
 //go:linkname initsig runtime.initsig
-//go:linkname crash runtime.crash
-//go:linkname resetcpuprofiler runtime.resetcpuprofiler
 //go:linkname sigtrampgo runtime.sigtrampgo
 
 //go:linkname os_sigpipe os.sigpipe
@@ -37,11 +36,18 @@
 // Stores the signal handlers registered before Go installed its own.
 // These signal handlers will be invoked in cases where Go doesn't want to
 // handle a particular signal (e.g., signal occurred on a non-Go thread).
-// See sigfwdgo() for more information on when the signals are forwarded.
+// See sigfwdgo for more information on when the signals are forwarded.
 //
-// Signal forwarding is currently available only on Darwin and Linux.
+// This is read by the signal handler; accesses should use
+// atomic.Loaduintptr and atomic.Storeuintptr.
 var fwdSig [_NSIG]uintptr
 
+// handlingSig is indexed by signal number and is non-zero if we are
+// currently handling the signal. Or, to put it another way, whether
+// the signal handler is currently set to the Go signal handler or not.
+// This is uint32 rather than bool so that we can use atomic instructions.
+var handlingSig [_NSIG]uint32
+
 // channels for synchronizing signal mask updates with the signal mask
 // thread
 var (
@@ -87,6 +93,9 @@
 		if t.flags == 0 || t.flags&_SigDefault != 0 {
 			continue
 		}
+
+		// We don't need to use atomic operations here because
+		// there shouldn't be any other goroutines running yet.
 		fwdSig[i] = getsig(i)
 
 		if !sigInstallGoHandler(i) {
@@ -98,7 +107,7 @@
 			continue
 		}
 
-		t.flags |= _SigHandling
+		handlingSig[i] = 1
 		setsig(i, getSigtramp())
 	}
 }
@@ -111,7 +120,7 @@
 	// Even these signals can be fetched using the os/signal package.
 	switch sig {
 	case _SIGHUP, _SIGINT:
-		if fwdSig[sig] == _SIG_IGN {
+		if atomic.Loaduintptr(&fwdSig[sig]) == _SIG_IGN {
 			return false
 		}
 	}
@@ -122,37 +131,52 @@
 	}
 
 	// When built using c-archive or c-shared, only install signal
-	// handlers for synchronous signals.
-	if (isarchive || islibrary) && t.flags&_SigPanic == 0 {
+	// handlers for synchronous signals and SIGPIPE.
+	if (isarchive || islibrary) && t.flags&_SigPanic == 0 && sig != _SIGPIPE {
 		return false
 	}
 
 	return true
 }
 
+// sigenable enables the Go signal handler to catch the signal sig.
+// It is only called while holding the os/signal.handlers lock,
+// via os/signal.enableSignal and signal_enable.
 func sigenable(sig uint32) {
 	if sig >= uint32(len(sigtable)) {
 		return
 	}
 
+	// SIGPROF is handled specially for profiling.
+	if sig == _SIGPROF {
+		return
+	}
+
 	t := &sigtable[sig]
 	if t.flags&_SigNotify != 0 {
 		ensureSigM()
 		enableSigChan <- sig
 		<-maskUpdatedChan
-		if t.flags&_SigHandling == 0 {
-			t.flags |= _SigHandling
-			fwdSig[sig] = getsig(sig)
+		if atomic.Cas(&handlingSig[sig], 0, 1) {
+			atomic.Storeuintptr(&fwdSig[sig], getsig(sig))
 			setsig(sig, getSigtramp())
 		}
 	}
 }
 
+// sigdisable disables the Go signal handler for the signal sig.
+// It is only called while holding the os/signal.handlers lock,
+// via os/signal.disableSignal and signal_disable.
 func sigdisable(sig uint32) {
 	if sig >= uint32(len(sigtable)) {
 		return
 	}
 
+	// SIGPROF is handled specially for profiling.
+	if sig == _SIGPROF {
+		return
+	}
+
 	t := &sigtable[sig]
 	if t.flags&_SigNotify != 0 {
 		ensureSigM()
@@ -163,25 +187,71 @@
 		// signal, then to go back to the state before Notify
 		// we should remove the one we installed.
 		if !sigInstallGoHandler(sig) {
-			t.flags &^= _SigHandling
-			setsig(sig, fwdSig[sig])
+			atomic.Store(&handlingSig[sig], 0)
+			setsig(sig, atomic.Loaduintptr(&fwdSig[sig]))
 		}
 	}
 }
 
+// sigignore ignores the signal sig.
+// It is only called while holding the os/signal.handlers lock,
+// via os/signal.ignoreSignal and signal_ignore.
 func sigignore(sig uint32) {
 	if sig >= uint32(len(sigtable)) {
 		return
 	}
 
+	// SIGPROF is handled specially for profiling.
+	if sig == _SIGPROF {
+		return
+	}
+
 	t := &sigtable[sig]
 	if t.flags&_SigNotify != 0 {
-		t.flags &^= _SigHandling
+		atomic.Store(&handlingSig[sig], 0)
 		setsig(sig, _SIG_IGN)
 	}
 }
 
-func resetcpuprofiler(hz int32) {
+// clearSignalHandlers clears all signal handlers that are not ignored
+// back to the default. This is called by the child after a fork, so that
+// we can enable the signal mask for the exec without worrying about
+// running a signal handler in the child.
+//go:nosplit
+//go:nowritebarrierrec
+func clearSignalHandlers() {
+	for i := uint32(0); i < _NSIG; i++ {
+		if atomic.Load(&handlingSig[i]) != 0 {
+			setsig(i, _SIG_DFL)
+		}
+	}
+}
+
+// setProcessCPUProfiler is called when the profiling timer changes.
+// It is called with prof.lock held. hz is the new timer, and is 0 if
+// profiling is being disabled. Enable or disable the signal as
+// required for -buildmode=c-archive.
+func setProcessCPUProfiler(hz int32) {
+	if hz != 0 {
+		// Enable the Go signal handler if not enabled.
+		if atomic.Cas(&handlingSig[_SIGPROF], 0, 1) {
+			atomic.Storeuintptr(&fwdSig[_SIGPROF], getsig(_SIGPROF))
+			setsig(_SIGPROF, funcPC(sighandler))
+		}
+	} else {
+		// If the Go signal handler should be disabled by default,
+		// disable it if it is enabled.
+		if !sigInstallGoHandler(_SIGPROF) {
+			if atomic.Cas(&handlingSig[_SIGPROF], 1, 0) {
+				setsig(_SIGPROF, atomic.Loaduintptr(&fwdSig[_SIGPROF]))
+			}
+		}
+	}
+}
+
+// setThreadCPUProfiler makes any thread-specific changes required to
+// implement profiling at a rate of hz.
+func setThreadCPUProfiler(hz int32) {
 	var it _itimerval
 	if hz == 0 {
 		setitimer(_ITIMER_PROF, &it, nil)
@@ -315,7 +385,7 @@
 	if sig >= _NSIG {
 		handler = _SIG_DFL
 	} else {
-		handler = fwdSig[sig]
+		handler = atomic.Loaduintptr(&fwdSig[sig])
 	}
 
 	// Reset the signal handler and raise the signal.
@@ -431,6 +501,16 @@
 	throw("non-Go code set up signal handler without SA_ONSTACK flag")
 }
 
+// signalDuringFork is called if we receive a signal while doing a fork.
+// We do not want signals at that time, as a signal sent to the process
+// group may be delivered to the child process, causing confusion.
+// This should never be called, because we block signals across the fork;
+// this function is just a safety check. See issue 18600 for background.
+func signalDuringFork(sig uint32) {
+	println("signal", sig, "received during fork")
+	throw("signal received during fork")
+}
+
 // This runs on a foreign stack, without an m or a g. No stack split.
 //go:nosplit
 //go:norace
@@ -455,7 +535,7 @@
 	if sig >= uint32(len(sigtable)) {
 		return false
 	}
-	fwdFn := fwdSig[sig]
+	fwdFn := atomic.Loaduintptr(&fwdSig[sig])
 
 	if !signalsOK {
 		// The only way we can get here is if we are in a
@@ -470,35 +550,44 @@
 		return true
 	}
 
-	flags := sigtable[sig].flags
-
 	// If there is no handler to forward to, no need to forward.
 	if fwdFn == _SIG_DFL {
 		return false
 	}
 
 	// If we aren't handling the signal, forward it.
-	if flags&_SigHandling == 0 {
+	// Really if we aren't handling the signal, we shouldn't get here,
+	// but on Darwin setsigstack can lead us here because it sets
+	// the sa_tramp field. The sa_tramp field is not returned by
+	// sigaction, so the fix for that is non-obvious.
+	if atomic.Load(&handlingSig[sig]) == 0 {
 		sigfwd(fwdFn, sig, info, ctx)
 		return true
 	}
 
-	// Only forward synchronous signals.
+	flags := sigtable[sig].flags
+
 	c := sigctxt{info, ctx}
-	if c.sigcode() == _SI_USER || flags&_SigPanic == 0 {
+	// Only forward synchronous signals and SIGPIPE.
+	// Unfortunately, user generated SIGPIPEs will also be forwarded, because si_code
+	// is set to _SI_USER even for a SIGPIPE raised from a write to a closed socket
+	// or pipe.
+	if (c.sigcode() == _SI_USER || flags&_SigPanic == 0) && sig != _SIGPIPE {
 		return false
 	}
 	// Determine if the signal occurred inside Go code. We test that:
 	//   (1) we were in a goroutine (i.e., m.curg != nil), and
-	//   (2) we weren't in CGO (i.e., m.curg.syscallsp == 0).
+	//   (2) we weren't in CGO.
 	g := getg()
-	if g != nil && g.m != nil && g.m.curg != nil && g.m.curg.syscallsp == 0 {
+	if g != nil && g.m != nil && g.m.curg != nil && !g.m.incgo {
 		return false
 	}
+
 	// Signal not handled by Go, forward it.
 	if fwdFn != _SIG_IGN {
 		sigfwd(fwdFn, sig, info, ctx)
 	}
+
 	return true
 }
 
diff --git a/libgo/go/runtime/sigqueue.go b/libgo/go/runtime/sigqueue.go
index a6d498f..cd036ce 100644
--- a/libgo/go/runtime/sigqueue.go
+++ b/libgo/go/runtime/sigqueue.go
@@ -33,6 +33,17 @@
 	_ "unsafe" // for go:linkname
 )
 
+// sig handles communication between the signal handler and os/signal.
+// Other than the inuse and recv fields, the fields are accessed atomically.
+//
+// The wanted and ignored fields are only written by one goroutine at
+// a time; access is controlled by the handlers Mutex in os/signal.
+// The fields are only read by that one goroutine and by the signal handler.
+// We access them atomically to minimize the race between setting them
+// in the goroutine calling os/signal and the signal handler,
+// which may be running in a different thread. That race is unavoidable,
+// as there is no connection between handling a signal and receiving one,
+// but atomic instructions should minimize it.
 var sig struct {
 	note    note
 	mask    [(_NSIG + 31) / 32]uint32
@@ -53,7 +64,11 @@
 // Reports whether the signal was sent. If not, the caller typically crashes the program.
 func sigsend(s uint32) bool {
 	bit := uint32(1) << uint(s&31)
-	if !sig.inuse || s >= uint32(32*len(sig.wanted)) || sig.wanted[s/32]&bit == 0 {
+	if !sig.inuse || s >= uint32(32*len(sig.wanted)) {
+		return false
+	}
+
+	if w := atomic.Load(&sig.wanted[s/32]); w&bit == 0 {
 		return false
 	}
 
@@ -131,6 +146,23 @@
 	}
 }
 
+// signalWaitUntilIdle waits until the signal delivery mechanism is idle.
+// This is used to ensure that we do not drop a signal notification due
+// to a race between disabling a signal and receiving a signal.
+// This assumes that signal delivery has already been disabled for
+// the signal(s) in question, and here we are just waiting to make sure
+// that all the signals have been delivered to the user channels
+// by the os/signal package.
+//go:linkname signalWaitUntilIdle os_signal.signalWaitUntilIdle
+func signalWaitUntilIdle() {
+	// Although WaitUntilIdle seems like the right name for this
+	// function, the state we are looking for is sigReceiving, not
+	// sigIdle.  The sigIdle state is really more like sigProcessing.
+	for atomic.Load(&sig.state) != sigReceiving {
+		Gosched()
+	}
+}
+
 // Must only be called from a single goroutine at a time.
 //go:linkname signal_enable os_signal.signal_enable
 func signal_enable(s uint32) {
@@ -146,8 +178,15 @@
 	if s >= uint32(len(sig.wanted)*32) {
 		return
 	}
-	sig.wanted[s/32] |= 1 << (s & 31)
-	sig.ignored[s/32] &^= 1 << (s & 31)
+
+	w := sig.wanted[s/32]
+	w |= 1 << (s & 31)
+	atomic.Store(&sig.wanted[s/32], w)
+
+	i := sig.ignored[s/32]
+	i &^= 1 << (s & 31)
+	atomic.Store(&sig.ignored[s/32], i)
+
 	sigenable(s)
 }
 
@@ -157,8 +196,11 @@
 	if s >= uint32(len(sig.wanted)*32) {
 		return
 	}
-	sig.wanted[s/32] &^= 1 << (s & 31)
 	sigdisable(s)
+
+	w := sig.wanted[s/32]
+	w &^= 1 << (s & 31)
+	atomic.Store(&sig.wanted[s/32], w)
 }
 
 // Must only be called from a single goroutine at a time.
@@ -167,12 +209,19 @@
 	if s >= uint32(len(sig.wanted)*32) {
 		return
 	}
-	sig.wanted[s/32] &^= 1 << (s & 31)
-	sig.ignored[s/32] |= 1 << (s & 31)
 	sigignore(s)
+
+	w := sig.wanted[s/32]
+	w &^= 1 << (s & 31)
+	atomic.Store(&sig.wanted[s/32], w)
+
+	i := sig.ignored[s/32]
+	i |= 1 << (s & 31)
+	atomic.Store(&sig.ignored[s/32], i)
 }
 
 // Checked by signal handlers.
 func signal_ignored(s uint32) bool {
-	return sig.ignored[s/32]&(1<<(s&31)) != 0
+	i := atomic.Load(&sig.ignored[s/32])
+	return i&(1<<(s&31)) != 0
 }
diff --git a/libgo/go/runtime/sizeclasses.go b/libgo/go/runtime/sizeclasses.go
index e616e95..5366564 100644
--- a/libgo/go/runtime/sizeclasses.go
+++ b/libgo/go/runtime/sizeclasses.go
@@ -1,4 +1,4 @@
-// AUTO-GENERATED by mksizeclasses.go; DO NOT EDIT
+// Code generated by mksizeclasses.go; DO NOT EDIT.
 //go:generate go run mksizeclasses.go
 
 package runtime
diff --git a/libgo/go/runtime/string.go b/libgo/go/runtime/string.go
index 9cc2873..7436ddf 100644
--- a/libgo/go/runtime/string.go
+++ b/libgo/go/runtime/string.go
@@ -88,7 +88,7 @@
 
 // Buf is a fixed-size buffer for the result,
 // it is not nil if the result does not escape.
-func slicebytetostring(buf *tmpBuf, b []byte) string {
+func slicebytetostring(buf *tmpBuf, b []byte) (str string) {
 	l := len(b)
 	if l == 0 {
 		// Turns out to be a relatively common case.
@@ -96,18 +96,26 @@
 		// you find the indices and convert the subslice to string.
 		return ""
 	}
-	if raceenabled && l > 0 {
+	if raceenabled {
 		racereadrangepc(unsafe.Pointer(&b[0]),
 			uintptr(l),
 			getcallerpc(unsafe.Pointer(&buf)),
 			funcPC(slicebytetostring))
 	}
-	if msanenabled && l > 0 {
+	if msanenabled {
 		msanread(unsafe.Pointer(&b[0]), uintptr(l))
 	}
-	s, c := rawstringtmp(buf, l)
-	copy(c, b)
-	return s
+
+	var p unsafe.Pointer
+	if buf != nil && len(b) <= len(buf) {
+		p = unsafe.Pointer(buf)
+	} else {
+		p = mallocgc(uintptr(len(b)), nil, false)
+	}
+	stringStructOf(&str).str = p
+	stringStructOf(&str).len = len(b)
+	memmove(p, (*(*slice)(unsafe.Pointer(&b))).array, uintptr(len(b)))
+	return
 }
 
 func rawstringtmp(buf *tmpBuf, l int) (s string, b []byte) {
diff --git a/libgo/go/runtime/string_test.go b/libgo/go/runtime/string_test.go
index ee30699..555a7fc 100644
--- a/libgo/go/runtime/string_test.go
+++ b/libgo/go/runtime/string_test.go
@@ -6,6 +6,7 @@
 
 import (
 	"runtime"
+	"strconv"
 	"strings"
 	"testing"
 )
@@ -89,6 +90,20 @@
 	}
 }
 
+var escapeString string
+
+func BenchmarkSliceByteToString(b *testing.B) {
+	buf := []byte{'!'}
+	for n := 0; n < 8; n++ {
+		b.Run(strconv.Itoa(len(buf)), func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				escapeString = string(buf)
+			}
+		})
+		buf = append(buf, buf...)
+	}
+}
+
 var stringdata = []struct{ name, data string }{
 	{"ASCII", "01234567890"},
 	{"Japanese", "日本語日本語日本語"},
diff --git a/libgo/go/runtime/stubs.go b/libgo/go/runtime/stubs.go
index 30d87c4..84fa1c7 100644
--- a/libgo/go/runtime/stubs.go
+++ b/libgo/go/runtime/stubs.go
@@ -109,8 +109,22 @@
 // exported value for testing
 var hashLoad = loadFactor
 
-// in asm_*.s
-func fastrand() uint32
+//go:nosplit
+func fastrand() uint32 {
+	mp := getg().m
+	fr := mp.fastrand
+	mx := uint32(int32(fr)>>31) & 0xa8888eef
+	fr = fr<<1 ^ mx
+	mp.fastrand = fr
+	return fr
+}
+
+//go:nosplit
+func fastrandn(n uint32) uint32 {
+	// This is similar to fastrand() % n, but faster.
+	// See http://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction/
+	return uint32(uint64(fastrand()) * uint64(n) >> 32)
+}
 
 //go:linkname sync_fastrand sync.fastrand
 func sync_fastrand() uint32 { return fastrand() }
@@ -156,7 +170,7 @@
 // This function must never be called directly. Call goexit1 instead.
 // gentraceback assumes that goexit terminates the stack. A direct
 // call on the stack will cause gentraceback to stop walking the stack
-// prematurely and if there are leftover stack barriers it may panic.
+// prematurely and if there is leftover state it may panic.
 func goexit(neverCallThisFunction)
 
 // publicationBarrier performs a store/store barrier (a "publication"
@@ -176,9 +190,6 @@
 // data dependency ordering.
 func publicationBarrier()
 
-//go:noescape
-func setcallerpc(argp unsafe.Pointer, pc uintptr)
-
 // getcallerpc returns the program counter (PC) of its caller's caller.
 // getcallersp returns the stack pointer (SP) of its caller's caller.
 // For both, the argp must be a pointer to the caller's first function argument.
@@ -213,12 +224,14 @@
 //go:noescape
 func getcallersp(argp unsafe.Pointer) uintptr
 
+func asmcgocall(fn, arg unsafe.Pointer) int32 {
+	throw("asmcgocall")
+	return 0
+}
+
 // argp used in Defer structs when there is no argp.
 const _NoArgs = ^uintptr(0)
 
-//go:linkname time_now time.now
-func time_now() (sec int64, nsec int32)
-
 //extern __builtin_prefetch
 func prefetch(addr unsafe.Pointer, rw int32, locality int32)
 
@@ -238,13 +251,6 @@
 	prefetch(unsafe.Pointer(addr), 0, 0)
 }
 
-// For gccgo, expose this for C callers.
-//go:linkname unixnanotime runtime.unixnanotime
-func unixnanotime() int64 {
-	sec, nsec := time_now()
-	return sec*1e9 + int64(nsec)
-}
-
 // round n up to a multiple of a.  a must be a power of 2.
 func round(n, a uintptr) uintptr {
 	return (n + a - 1) &^ (a - 1)
@@ -315,18 +321,6 @@
 // Here for gccgo until we port mgc.go.
 func GC()
 
-// For gccgo to call from C code.
-//go:linkname acquireWorldsema runtime.acquireWorldsema
-func acquireWorldsema() {
-	semacquire(&worldsema, 0)
-}
-
-// For gccgo to call from C code.
-//go:linkname releaseWorldsema runtime.releaseWorldsema
-func releaseWorldsema() {
-	semrelease(&worldsema)
-}
-
 // For gccgo to call from C code, so that the C code and the Go code
 // can share the memstats variable for now.
 //go:linkname getMstats runtime.getMstats
@@ -436,10 +430,6 @@
 	}
 }
 
-// Temporary for gccgo until we port more of proc.go.
-func sigprofNonGoPC(pc uintptr) {
-}
-
 // Temporary for gccgo until we port mgc.go.
 //go:linkname runtime_m0 runtime.runtime_m0
 func runtime_m0() *m {
@@ -458,3 +448,11 @@
 	n        int32 // # of bits
 	bytedata *uint8
 }
+
+// bool2int returns 0 if x is false or 1 if x is true.
+func bool2int(x bool) int {
+	if x {
+		return 1
+	}
+	return 0
+}
diff --git a/libgo/go/runtime/stubs_linux.go b/libgo/go/runtime/stubs_linux.go
new file mode 100644
index 0000000..d10f657
--- /dev/null
+++ b/libgo/go/runtime/stubs_linux.go
@@ -0,0 +1,9 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+
+package runtime
+
+func sbrk0() uintptr
diff --git a/libgo/go/runtime/stubs_nonlinux.go b/libgo/go/runtime/stubs_nonlinux.go
new file mode 100644
index 0000000..e1ea05c
--- /dev/null
+++ b/libgo/go/runtime/stubs_nonlinux.go
@@ -0,0 +1,12 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !linux
+
+package runtime
+
+// sbrk0 returns the current process brk, or 0 if not implemented.
+func sbrk0() uintptr {
+	return 0
+}
diff --git a/libgo/go/runtime/symtab.go b/libgo/go/runtime/symtab.go
index bad0347..3d15fc8 100644
--- a/libgo/go/runtime/symtab.go
+++ b/libgo/go/runtime/symtab.go
@@ -7,6 +7,7 @@
 // Frames may be used to get function/file/line information for a
 // slice of PC values returned by Callers.
 type Frames struct {
+	// callers is a slice of PCs that have not yet been expanded.
 	callers []uintptr
 
 	// The last PC we saw.
@@ -18,23 +19,34 @@
 
 // Frame is the information returned by Frames for each call frame.
 type Frame struct {
-	// Program counter for this frame; multiple frames may have
-	// the same PC value.
+	// PC is the program counter for the location in this frame.
+	// For a frame that calls another frame, this will be the
+	// program counter of a call instruction. Because of inlining,
+	// multiple frames may have the same PC value, but different
+	// symbolic information.
 	PC uintptr
 
-	// Func for this frame; may be nil for non-Go code or fully
-	// inlined functions.
+	// Func is the Func value of this call frame. This may be nil
+	// for non-Go code or fully inlined functions.
 	Func *Func
 
-	// Function name, file name, and line number for this call frame.
-	// May be the empty string or zero if not known.
+	// Function is the package path-qualified function name of
+	// this call frame. If non-empty, this string uniquely
+	// identifies a single function in the program.
+	// This may be the empty string if not known.
 	// If Func is not nil then Function == Func.Name().
 	Function string
-	File     string
-	Line     int
 
-	// Entry point for the function; may be zero if not known.
-	// If Func is not nil then Entry == Func.Entry().
+	// File and Line are the file name and line number of the
+	// location in this frame. For non-leaf frames, this will be
+	// the location of a call. These may be the empty string and
+	// zero, respectively, if not known.
+	File string
+	Line int
+
+	// Entry point program counter for the function; may be zero
+	// if not known. If Func is not nil then Entry ==
+	// Func.Entry().
 	Entry uintptr
 }
 
@@ -94,7 +106,8 @@
 // NOTE: Func does not expose the actual unexported fields, because we return *Func
 // values to users, and we want to keep them from being able to overwrite the data
 // with (say) *f = Func{}.
-// All code operating on a *Func must call raw to get the *_func instead.
+// All code operating on a *Func must call raw() to get the *_func
+// or funcInfo() to get the funcInfo instead.
 
 // A Func represents a Go function in the running binary.
 type Func struct {
@@ -104,6 +117,9 @@
 
 // FuncForPC returns a *Func describing the function that contains the
 // given program counter address, or else nil.
+//
+// If pc represents multiple functions because of inlining, it returns
+// the *Func describing the outermost function.
 func FuncForPC(pc uintptr) *Func {
 	name, _, _ := funcfileline(pc, -1)
 	if name == "" {
diff --git a/libgo/go/runtime/symtab_test.go b/libgo/go/runtime/symtab_test.go
index 8c8281f..807b50d 100644
--- a/libgo/go/runtime/symtab_test.go
+++ b/libgo/go/runtime/symtab_test.go
@@ -31,10 +31,14 @@
 	}
 }
 
+// These are marked noinline so that we can use FuncForPC
+// in testCallerBar.
+//go:noinline
 func testCallerFoo(t *testing.T) {
 	testCallerBar(t)
 }
 
+//go:noinline
 func testCallerBar(t *testing.T) {
 	for i := 0; i < 2; i++ {
 		pc, file, line, ok := runtime.Caller(i)
@@ -94,7 +98,7 @@
 }                           // 33
 var intLit = lineNumber() + // 34
 	lineNumber() + // 35
-			lineNumber() // 36
+	lineNumber() // 36
 func trythis() { // 37
 	recordLines(lineNumber(), // 38
 		lineNumber(), // 39
@@ -156,3 +160,14 @@
 		}
 	}
 }
+
+func TestNilName(t *testing.T) {
+	defer func() {
+		if ex := recover(); ex != nil {
+			t.Fatalf("expected no nil panic, got=%v", ex)
+		}
+	}()
+	if got := (*runtime.Func)(nil).Name(); got != "" {
+		t.Errorf("Name() = %q, want %q", got, "")
+	}
+}
diff --git a/libgo/go/runtime/testdata/testprog/numcpu_freebsd.go b/libgo/go/runtime/testdata/testprog/numcpu_freebsd.go
new file mode 100644
index 0000000..035c534
--- /dev/null
+++ b/libgo/go/runtime/testdata/testprog/numcpu_freebsd.go
@@ -0,0 +1,126 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"os/exec"
+	"runtime"
+	"strconv"
+	"strings"
+	"syscall"
+)
+
+func init() {
+	register("FreeBSDNumCPU", FreeBSDNumCPU)
+	register("FreeBSDNumCPUHelper", FreeBSDNumCPUHelper)
+}
+
+func FreeBSDNumCPUHelper() {
+	fmt.Printf("%d\n", runtime.NumCPU())
+}
+
+func FreeBSDNumCPU() {
+	_, err := exec.LookPath("cpuset")
+	if err != nil {
+		// Can not test without cpuset command.
+		fmt.Println("OK")
+		return
+	}
+	_, err = exec.LookPath("sysctl")
+	if err != nil {
+		// Can not test without sysctl command.
+		fmt.Println("OK")
+		return
+	}
+	cmd := exec.Command("sysctl", "-n", "kern.smp.active")
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		fmt.Printf("fail to launch '%s', error: %s, output: %s\n", strings.Join(cmd.Args, " "), err, output)
+		return
+	}
+	if bytes.Equal(output, []byte("1\n")) == false {
+		// SMP mode deactivated in kernel.
+		fmt.Println("OK")
+		return
+	}
+
+	list, err := getList()
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	err = checkNCPU(list)
+	if err != nil {
+		fmt.Printf("%s\n", err)
+		return
+	}
+	if len(list) >= 2 {
+		err = checkNCPU(list[:len(list)-1])
+		if err != nil {
+			fmt.Printf("%s\n", err)
+			return
+		}
+	}
+	fmt.Println("OK")
+	return
+}
+
+func getList() ([]string, error) {
+	pid := syscall.Getpid()
+
+	// Launch cpuset to print a list of available CPUs: pid <PID> mask: 0, 1, 2, 3.
+	cmd := exec.Command("cpuset", "-g", "-p", strconv.Itoa(pid))
+	cmdline := strings.Join(cmd.Args, " ")
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return nil, fmt.Errorf("fail to execute '%s': %s", cmdline, err)
+	}
+	pos := bytes.IndexRune(output, ':')
+	if pos == -1 {
+		return nil, fmt.Errorf("invalid output from '%s', ':' not found: %s", cmdline, output)
+	}
+
+	var list []string
+	for _, val := range bytes.Split(output[pos+1:], []byte(",")) {
+		index := string(bytes.TrimSpace(val))
+		if len(index) == 0 {
+			continue
+		}
+		list = append(list, index)
+	}
+	if len(list) == 0 {
+		return nil, fmt.Errorf("empty CPU list from '%s': %s", cmdline, output)
+	}
+	return list, nil
+}
+
+func checkNCPU(list []string) error {
+	listString := strings.Join(list, ",")
+	if len(listString) == 0 {
+		return fmt.Errorf("could not check against an empty CPU list")
+	}
+
+	// Launch FreeBSDNumCPUHelper() with specified CPUs list.
+	cmd := exec.Command("cpuset", "-l", listString, os.Args[0], "FreeBSDNumCPUHelper")
+	cmdline := strings.Join(cmd.Args, " ")
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("fail to launch child '%s', error: %s, output: %s", cmdline, err, output)
+	}
+
+	// NumCPU from FreeBSDNumCPUHelper come with '\n'.
+	output = bytes.TrimSpace(output)
+	n, err := strconv.Atoi(string(output))
+	if err != nil {
+		return fmt.Errorf("fail to parse output from child '%s', error: %s, output: %s", cmdline, err, output)
+	}
+	if n != len(list) {
+		return fmt.Errorf("runtime.NumCPU() expected to %d, got %d when run with CPU list %s", len(list), n, listString)
+	}
+	return nil
+}
diff --git a/libgo/go/runtime/testdata/testprog/panicrace.go b/libgo/go/runtime/testdata/testprog/panicrace.go
new file mode 100644
index 0000000..f058994
--- /dev/null
+++ b/libgo/go/runtime/testdata/testprog/panicrace.go
@@ -0,0 +1,27 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"runtime"
+	"sync"
+)
+
+func init() {
+	register("PanicRace", PanicRace)
+}
+
+func PanicRace() {
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func() {
+		defer func() {
+			wg.Done()
+			runtime.Gosched()
+		}()
+		panic("crash")
+	}()
+	wg.Wait()
+}
diff --git a/libgo/go/runtime/testdata/testprogcgo/cgo.go b/libgo/go/runtime/testdata/testprogcgo/cgo.go
index 870d4ef..209524a 100644
--- a/libgo/go/runtime/testdata/testprogcgo/cgo.go
+++ b/libgo/go/runtime/testdata/testprogcgo/cgo.go
@@ -45,10 +45,13 @@
 				}()
 				var s *string
 				*s = ""
+				fmt.Printf("continued after expected panic\n")
 			}()
 		}
 	}()
 	time.Sleep(time.Millisecond)
+	start := time.Now()
+	var times []time.Duration
 	for i := 0; i < 64; i++ {
 		go func() {
 			runtime.LockOSThread()
@@ -62,8 +65,9 @@
 		ping <- false
 		select {
 		case <-ping:
+			times = append(times, time.Since(start))
 		case <-time.After(time.Second):
-			fmt.Printf("HANG\n")
+			fmt.Printf("HANG 1 %v\n", times)
 			return
 		}
 	}
@@ -71,7 +75,7 @@
 	select {
 	case <-ping:
 	case <-time.After(time.Second):
-		fmt.Printf("HANG\n")
+		fmt.Printf("HANG 2 %v\n", times)
 		return
 	}
 	fmt.Printf("OK\n")
diff --git a/libgo/go/runtime/testdata/testprogcgo/numgoroutine.go b/libgo/go/runtime/testdata/testprogcgo/numgoroutine.go
new file mode 100644
index 0000000..12fda49
--- /dev/null
+++ b/libgo/go/runtime/testdata/testprogcgo/numgoroutine.go
@@ -0,0 +1,99 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !plan9,!windows
+
+package main
+
+/*
+#include <stddef.h>
+#include <pthread.h>
+
+extern void CallbackNumGoroutine();
+
+static void* thread2(void* arg __attribute__ ((unused))) {
+	CallbackNumGoroutine();
+	return NULL;
+}
+
+static void CheckNumGoroutine() {
+	pthread_t tid;
+	pthread_create(&tid, NULL, thread2, NULL);
+	pthread_join(tid, NULL);
+}
+*/
+import "C"
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+)
+
+var baseGoroutines int
+
+func init() {
+	register("NumGoroutine", NumGoroutine)
+}
+
+func NumGoroutine() {
+	// Test that there are just the expected number of goroutines
+	// running. Specifically, test that the spare M's goroutine
+	// doesn't show up.
+	//
+	// On non-Windows platforms there's a signal handling thread
+	// started by os/signal.init in addition to the main
+	// goroutine.
+	if runtime.GOOS != "windows" {
+		baseGoroutines = 1
+	}
+	if _, ok := checkNumGoroutine("first", 1+baseGoroutines); !ok {
+		return
+	}
+
+	// Test that the goroutine for a callback from C appears.
+	if C.CheckNumGoroutine(); !callbackok {
+		return
+	}
+
+	// Make sure we're back to the initial goroutines.
+	if _, ok := checkNumGoroutine("third", 1+baseGoroutines); !ok {
+		return
+	}
+
+	fmt.Println("OK")
+}
+
+func checkNumGoroutine(label string, want int) (string, bool) {
+	n := runtime.NumGoroutine()
+	if n != want {
+		fmt.Printf("%s NumGoroutine: want %d; got %d\n", label, want, n)
+		return "", false
+	}
+
+	sbuf := make([]byte, 32<<10)
+	sbuf = sbuf[:runtime.Stack(sbuf, true)]
+	n = strings.Count(string(sbuf), "goroutine ")
+	if n != want {
+		fmt.Printf("%s Stack: want %d; got %d:\n%s\n", label, want, n, string(sbuf))
+		return "", false
+	}
+	return string(sbuf), true
+}
+
+var callbackok bool
+
+//export CallbackNumGoroutine
+func CallbackNumGoroutine() {
+	stk, ok := checkNumGoroutine("second", 2+baseGoroutines)
+	if !ok {
+		return
+	}
+	if !strings.Contains(stk, "CallbackNumGoroutine") {
+		fmt.Printf("missing CallbackNumGoroutine from stack:\n%s\n", stk)
+		return
+	}
+
+	callbackok = true
+}
diff --git a/libgo/go/runtime/testdata/testprognet/signalexec.go b/libgo/go/runtime/testdata/testprognet/signalexec.go
new file mode 100644
index 0000000..4a988ef
--- /dev/null
+++ b/libgo/go/runtime/testdata/testprognet/signalexec.go
@@ -0,0 +1,70 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd
+
+// This is in testprognet instead of testprog because testprog
+// must not import anything (like net, but also like os/signal)
+// that kicks off background goroutines during init.
+
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"os/signal"
+	"sync"
+	"syscall"
+	"time"
+)
+
+func init() {
+	register("SignalDuringExec", SignalDuringExec)
+	register("Nop", Nop)
+}
+
+func SignalDuringExec() {
+	pgrp := syscall.Getpgrp()
+
+	const tries = 10
+
+	var wg sync.WaitGroup
+	c := make(chan os.Signal, tries)
+	signal.Notify(c, syscall.SIGWINCH)
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		for range c {
+		}
+	}()
+
+	for i := 0; i < tries; i++ {
+		time.Sleep(time.Microsecond)
+		wg.Add(2)
+		go func() {
+			defer wg.Done()
+			cmd := exec.Command(os.Args[0], "Nop")
+			cmd.Stdout = os.Stdout
+			cmd.Stderr = os.Stderr
+			if err := cmd.Run(); err != nil {
+				fmt.Printf("Start failed: %v", err)
+			}
+		}()
+		go func() {
+			defer wg.Done()
+			syscall.Kill(-pgrp, syscall.SIGWINCH)
+		}()
+	}
+
+	signal.Stop(c)
+	close(c)
+	wg.Wait()
+
+	fmt.Println("OK")
+}
+
+func Nop() {
+	// This is just for SignalDuringExec.
+}
diff --git a/libgo/go/runtime/time.go b/libgo/go/runtime/time.go
index cc167a8..f204830 100644
--- a/libgo/go/runtime/time.go
+++ b/libgo/go/runtime/time.go
@@ -31,6 +31,7 @@
 	created      bool
 	sleeping     bool
 	rescheduling bool
+	sleepUntil   int64
 	waitnote     note
 	t            []*timer
 }
@@ -50,7 +51,12 @@
 		return
 	}
 
-	t := new(timer)
+	t := getg().timer
+	if t == nil {
+		t = new(timer)
+		getg().timer = t
+	}
+	*t = timer{}
 	t.when = nanotime() + ns
 	t.f = goroutineReady
 	t.arg = getg()
@@ -207,6 +213,7 @@
 		}
 		// At least one timer pending. Sleep until then.
 		timers.sleeping = true
+		timers.sleepUntil = now + delta
 		noteclear(&timers.waitnote)
 		unlock(&timers.lock)
 		notetsleepg(&timers.waitnote, delta)
@@ -295,8 +302,8 @@
 
 // Entry points for net, time to call nanotime.
 
-//go:linkname net_runtimeNano net.runtimeNano
-func net_runtimeNano() int64 {
+//go:linkname poll_runtimeNano internal_poll.runtimeNano
+func poll_runtimeNano() int64 {
 	return nanotime()
 }
 
@@ -304,3 +311,5 @@
 func time_runtimeNano() int64 {
 	return nanotime()
 }
+
+var startNano int64 = nanotime()
diff --git a/libgo/go/runtime/timeasm.go b/libgo/go/runtime/timeasm.go
new file mode 100644
index 0000000..d5f5ea3
--- /dev/null
+++ b/libgo/go/runtime/timeasm.go
@@ -0,0 +1,17 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Declarations for operating systems implementing time.now directly in assembly.
+// Those systems are also expected to have nanotime subtract startNano,
+// so that time.now and nanotime return the same monotonic clock readings.
+
+// +build ignore
+// +build darwin,amd64 darwin,386 windows
+
+package runtime
+
+import _ "unsafe"
+
+//go:linkname time_now time.now
+func time_now() (sec int64, nsec int32, mono int64)
diff --git a/libgo/go/runtime/timestub.go b/libgo/go/runtime/timestub.go
new file mode 100644
index 0000000..033734e
--- /dev/null
+++ b/libgo/go/runtime/timestub.go
@@ -0,0 +1,21 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Declarations for operating systems implementing time.now
+// indirectly, in terms of walltime and nanotime assembly.
+
+// -build !darwin !amd64,!386
+// -build !windows
+
+package runtime
+
+import _ "unsafe" // for go:linkname
+
+func walltime() (sec int64, nsec int32)
+
+//go:linkname time_now time.now
+func time_now() (sec int64, nsec int32, mono int64) {
+	sec, nsec = walltime()
+	return sec, nsec, nanotime() - startNano
+}
diff --git a/libgo/go/runtime/trace.go b/libgo/go/runtime/trace.go
index 61cfa8e..af9313b 100644
--- a/libgo/go/runtime/trace.go
+++ b/libgo/go/runtime/trace.go
@@ -19,50 +19,52 @@
 
 // Event types in the trace, args are given in square brackets.
 const (
-	traceEvNone           = 0  // unused
-	traceEvBatch          = 1  // start of per-P batch of events [pid, timestamp]
-	traceEvFrequency      = 2  // contains tracer timer frequency [frequency (ticks per second)]
-	traceEvStack          = 3  // stack [stack id, number of PCs, array of {PC, func string ID, file string ID, line}]
-	traceEvGomaxprocs     = 4  // current value of GOMAXPROCS [timestamp, GOMAXPROCS, stack id]
-	traceEvProcStart      = 5  // start of P [timestamp, thread id]
-	traceEvProcStop       = 6  // stop of P [timestamp]
-	traceEvGCStart        = 7  // GC start [timestamp, seq, stack id]
-	traceEvGCDone         = 8  // GC done [timestamp]
-	traceEvGCScanStart    = 9  // GC mark termination start [timestamp]
-	traceEvGCScanDone     = 10 // GC mark termination done [timestamp]
-	traceEvGCSweepStart   = 11 // GC sweep start [timestamp, stack id]
-	traceEvGCSweepDone    = 12 // GC sweep done [timestamp]
-	traceEvGoCreate       = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]
-	traceEvGoStart        = 14 // goroutine starts running [timestamp, goroutine id, seq]
-	traceEvGoEnd          = 15 // goroutine ends [timestamp]
-	traceEvGoStop         = 16 // goroutine stops (like in select{}) [timestamp, stack]
-	traceEvGoSched        = 17 // goroutine calls Gosched [timestamp, stack]
-	traceEvGoPreempt      = 18 // goroutine is preempted [timestamp, stack]
-	traceEvGoSleep        = 19 // goroutine calls Sleep [timestamp, stack]
-	traceEvGoBlock        = 20 // goroutine blocks [timestamp, stack]
-	traceEvGoUnblock      = 21 // goroutine is unblocked [timestamp, goroutine id, seq, stack]
-	traceEvGoBlockSend    = 22 // goroutine blocks on chan send [timestamp, stack]
-	traceEvGoBlockRecv    = 23 // goroutine blocks on chan recv [timestamp, stack]
-	traceEvGoBlockSelect  = 24 // goroutine blocks on select [timestamp, stack]
-	traceEvGoBlockSync    = 25 // goroutine blocks on Mutex/RWMutex [timestamp, stack]
-	traceEvGoBlockCond    = 26 // goroutine blocks on Cond [timestamp, stack]
-	traceEvGoBlockNet     = 27 // goroutine blocks on network [timestamp, stack]
-	traceEvGoSysCall      = 28 // syscall enter [timestamp, stack]
-	traceEvGoSysExit      = 29 // syscall exit [timestamp, goroutine id, seq, real timestamp]
-	traceEvGoSysBlock     = 30 // syscall blocks [timestamp]
-	traceEvGoWaiting      = 31 // denotes that goroutine is blocked when tracing starts [timestamp, goroutine id]
-	traceEvGoInSyscall    = 32 // denotes that goroutine is in syscall when tracing starts [timestamp, goroutine id]
-	traceEvHeapAlloc      = 33 // memstats.heap_live change [timestamp, heap_alloc]
-	traceEvNextGC         = 34 // memstats.next_gc change [timestamp, next_gc]
-	traceEvTimerGoroutine = 35 // denotes timer goroutine [timer goroutine id]
-	traceEvFutileWakeup   = 36 // denotes that the previous wakeup of this goroutine was futile [timestamp]
-	traceEvString         = 37 // string dictionary entry [ID, length, string]
-	traceEvGoStartLocal   = 38 // goroutine starts running on the same P as the last event [timestamp, goroutine id]
-	traceEvGoUnblockLocal = 39 // goroutine is unblocked on the same P as the last event [timestamp, goroutine id, stack]
-	traceEvGoSysExitLocal = 40 // syscall exit on the same P as the last event [timestamp, goroutine id, real timestamp]
-	traceEvGoStartLabel   = 41 // goroutine starts running with label [timestamp, goroutine id, seq, label string id]
-	traceEvGoBlockGC      = 42 // goroutine blocks on GC assist [timestamp, stack]
-	traceEvCount          = 43
+	traceEvNone              = 0  // unused
+	traceEvBatch             = 1  // start of per-P batch of events [pid, timestamp]
+	traceEvFrequency         = 2  // contains tracer timer frequency [frequency (ticks per second)]
+	traceEvStack             = 3  // stack [stack id, number of PCs, array of {PC, func string ID, file string ID, line}]
+	traceEvGomaxprocs        = 4  // current value of GOMAXPROCS [timestamp, GOMAXPROCS, stack id]
+	traceEvProcStart         = 5  // start of P [timestamp, thread id]
+	traceEvProcStop          = 6  // stop of P [timestamp]
+	traceEvGCStart           = 7  // GC start [timestamp, seq, stack id]
+	traceEvGCDone            = 8  // GC done [timestamp]
+	traceEvGCScanStart       = 9  // GC mark termination start [timestamp]
+	traceEvGCScanDone        = 10 // GC mark termination done [timestamp]
+	traceEvGCSweepStart      = 11 // GC sweep start [timestamp, stack id]
+	traceEvGCSweepDone       = 12 // GC sweep done [timestamp, swept, reclaimed]
+	traceEvGoCreate          = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]
+	traceEvGoStart           = 14 // goroutine starts running [timestamp, goroutine id, seq]
+	traceEvGoEnd             = 15 // goroutine ends [timestamp]
+	traceEvGoStop            = 16 // goroutine stops (like in select{}) [timestamp, stack]
+	traceEvGoSched           = 17 // goroutine calls Gosched [timestamp, stack]
+	traceEvGoPreempt         = 18 // goroutine is preempted [timestamp, stack]
+	traceEvGoSleep           = 19 // goroutine calls Sleep [timestamp, stack]
+	traceEvGoBlock           = 20 // goroutine blocks [timestamp, stack]
+	traceEvGoUnblock         = 21 // goroutine is unblocked [timestamp, goroutine id, seq, stack]
+	traceEvGoBlockSend       = 22 // goroutine blocks on chan send [timestamp, stack]
+	traceEvGoBlockRecv       = 23 // goroutine blocks on chan recv [timestamp, stack]
+	traceEvGoBlockSelect     = 24 // goroutine blocks on select [timestamp, stack]
+	traceEvGoBlockSync       = 25 // goroutine blocks on Mutex/RWMutex [timestamp, stack]
+	traceEvGoBlockCond       = 26 // goroutine blocks on Cond [timestamp, stack]
+	traceEvGoBlockNet        = 27 // goroutine blocks on network [timestamp, stack]
+	traceEvGoSysCall         = 28 // syscall enter [timestamp, stack]
+	traceEvGoSysExit         = 29 // syscall exit [timestamp, goroutine id, seq, real timestamp]
+	traceEvGoSysBlock        = 30 // syscall blocks [timestamp]
+	traceEvGoWaiting         = 31 // denotes that goroutine is blocked when tracing starts [timestamp, goroutine id]
+	traceEvGoInSyscall       = 32 // denotes that goroutine is in syscall when tracing starts [timestamp, goroutine id]
+	traceEvHeapAlloc         = 33 // memstats.heap_live change [timestamp, heap_alloc]
+	traceEvNextGC            = 34 // memstats.next_gc change [timestamp, next_gc]
+	traceEvTimerGoroutine    = 35 // denotes timer goroutine [timer goroutine id]
+	traceEvFutileWakeup      = 36 // denotes that the previous wakeup of this goroutine was futile [timestamp]
+	traceEvString            = 37 // string dictionary entry [ID, length, string]
+	traceEvGoStartLocal      = 38 // goroutine starts running on the same P as the last event [timestamp, goroutine id]
+	traceEvGoUnblockLocal    = 39 // goroutine is unblocked on the same P as the last event [timestamp, goroutine id, stack]
+	traceEvGoSysExitLocal    = 40 // syscall exit on the same P as the last event [timestamp, goroutine id, real timestamp]
+	traceEvGoStartLabel      = 41 // goroutine starts running with label [timestamp, goroutine id, seq, label string id]
+	traceEvGoBlockGC         = 42 // goroutine blocks on GC assist [timestamp, stack]
+	traceEvGCMarkAssistStart = 43 // GC mark assist start [timestamp, stack]
+	traceEvGCMarkAssistDone  = 44 // GC mark assist done [timestamp]
+	traceEvCount             = 45
 )
 
 const (
@@ -311,7 +313,7 @@
 
 	// The world is started but we've set trace.shutdown, so new tracing can't start.
 	// Wait for the trace reader to flush pending buffers and stop.
-	semacquire(&trace.shutdownSema, 0)
+	semacquire(&trace.shutdownSema)
 	if raceenabled {
 		raceacquire(unsafe.Pointer(&trace.shutdownSema))
 	}
@@ -380,7 +382,7 @@
 		trace.headerWritten = true
 		trace.lockOwner = nil
 		unlock(&trace.lock)
-		return []byte("go 1.8 trace\x00\x00\x00\x00")
+		return []byte("go 1.9 trace\x00\x00\x00\x00")
 	}
 	// Wait for new data.
 	if trace.fullHead == 0 && !trace.shutdown {
@@ -776,11 +778,12 @@
 		for ; stk != nil; stk = stk.link.ptr() {
 			tmpbuf := tmp[:0]
 			tmpbuf = traceAppend(tmpbuf, uint64(stk.id))
-			tmpbuf = traceAppend(tmpbuf, uint64(stk.n))
-			for _, pc := range stk.stack() {
+			frames := stk.stack()
+			tmpbuf = traceAppend(tmpbuf, uint64(len(frames)))
+			for _, f := range frames {
 				var frame traceFrame
-				frame, buf = traceFrameForPC(buf, pc)
-				tmpbuf = traceAppend(tmpbuf, uint64(pc.pc))
+				frame, buf = traceFrameForPC(buf, f)
+				tmpbuf = traceAppend(tmpbuf, uint64(f.pc))
 				tmpbuf = traceAppend(tmpbuf, uint64(frame.funcID))
 				tmpbuf = traceAppend(tmpbuf, uint64(frame.fileID))
 				tmpbuf = traceAppend(tmpbuf, uint64(frame.line))
@@ -810,16 +813,17 @@
 	line   uint64
 }
 
-func traceFrameForPC(buf *traceBuf, loc location) (traceFrame, *traceBuf) {
+func traceFrameForPC(buf *traceBuf, f location) (traceFrame, *traceBuf) {
 	var frame traceFrame
-	fn := loc.function
+
+	fn := f.function
 	const maxLen = 1 << 10
 	if len(fn) > maxLen {
 		fn = fn[len(fn)-maxLen:]
 	}
 	frame.funcID, buf = traceString(buf, fn)
-	file, line := loc.filename, loc.lineno
-	frame.line = uint64(line)
+	frame.line = uint64(f.lineno)
+	file := f.filename
 	if len(file) > maxLen {
 		file = file[len(file)-maxLen:]
 	}
@@ -921,12 +925,52 @@
 	traceEvent(traceEvGCScanDone, -1)
 }
 
+// traceGCSweepStart prepares to trace a sweep loop. This does not
+// emit any events until traceGCSweepSpan is called.
+//
+// traceGCSweepStart must be paired with traceGCSweepDone and there
+// must be no preemption points between these two calls.
 func traceGCSweepStart() {
-	traceEvent(traceEvGCSweepStart, 1)
+	// Delay the actual GCSweepStart event until the first span
+	// sweep. If we don't sweep anything, don't emit any events.
+	_p_ := getg().m.p.ptr()
+	if _p_.traceSweep {
+		throw("double traceGCSweepStart")
+	}
+	_p_.traceSweep, _p_.traceSwept, _p_.traceReclaimed = true, 0, 0
+}
+
+// traceGCSweepSpan traces the sweep of a single page.
+//
+// This may be called outside a traceGCSweepStart/traceGCSweepDone
+// pair; however, it will not emit any trace events in this case.
+func traceGCSweepSpan(bytesSwept uintptr) {
+	_p_ := getg().m.p.ptr()
+	if _p_.traceSweep {
+		if _p_.traceSwept == 0 {
+			traceEvent(traceEvGCSweepStart, 1)
+		}
+		_p_.traceSwept += bytesSwept
+	}
 }
 
 func traceGCSweepDone() {
-	traceEvent(traceEvGCSweepDone, -1)
+	_p_ := getg().m.p.ptr()
+	if !_p_.traceSweep {
+		throw("missing traceGCSweepStart")
+	}
+	if _p_.traceSwept != 0 {
+		traceEvent(traceEvGCSweepDone, -1, uint64(_p_.traceSwept), uint64(_p_.traceReclaimed))
+	}
+	_p_.traceSweep = false
+}
+
+func traceGCMarkAssistStart() {
+	traceEvent(traceEvGCMarkAssistStart, 1)
+}
+
+func traceGCMarkAssistDone() {
+	traceEvent(traceEvGCMarkAssistDone, -1)
 }
 
 func traceGoCreate(newg *g, pc uintptr) {
@@ -967,7 +1011,7 @@
 	traceEvent(traceEvGoPreempt, 1)
 }
 
-func traceGoPark(traceEv byte, skip int, gp *g) {
+func traceGoPark(traceEv byte, skip int) {
 	if traceEv&traceFutileWakeup != 0 {
 		traceEvent(traceEvFutileWakeup, -1)
 	}
diff --git a/libgo/go/runtime/trace/trace_stack_test.go b/libgo/go/runtime/trace/trace_stack_test.go
index c37b33d..274cdf7 100644
--- a/libgo/go/runtime/trace/trace_stack_test.go
+++ b/libgo/go/runtime/trace/trace_stack_test.go
@@ -151,7 +151,7 @@
 			{"testing.tRunner", 0},
 		}},
 		{trace.EvGoCreate, []frame{
-			{"runtime/trace_test.TestTraceSymbolize", 39},
+			{"runtime/trace_test.TestTraceSymbolize", 37},
 			{"testing.tRunner", 0},
 		}},
 		{trace.EvGoStop, []frame{
@@ -231,6 +231,7 @@
 	if runtime.GOOS != "windows" && runtime.GOOS != "plan9" {
 		want = append(want, []eventDesc{
 			{trace.EvGoBlockNet, []frame{
+				{"internal/poll.(*FD).Accept", 0},
 				{"net.(*netFD).accept", 0},
 				{"net.(*TCPListener).accept", 0},
 				{"net.(*TCPListener).Accept", 0},
@@ -239,6 +240,7 @@
 			{trace.EvGoSysCall, []frame{
 				{"syscall.read", 0},
 				{"syscall.Read", 0},
+				{"internal/poll.(*FD).Read", 0},
 				{"os.(*File).read", 0},
 				{"os.(*File).Read", 0},
 				{"runtime/trace_test.TestTraceSymbolize.func11", 102},
@@ -274,9 +276,10 @@
 				continue
 			}
 			for _, f := range ev.Stk {
-				t.Logf("  %v:%v", f.Fn, f.Line)
+				t.Logf("  %v :: %s:%v", f.Fn, f.File, f.Line)
 			}
 			t.Logf("---")
 		}
+		t.Logf("======")
 	}
 }
diff --git a/libgo/go/runtime/traceback_gccgo.go b/libgo/go/runtime/traceback_gccgo.go
index 715772e..f29ccd7 100644
--- a/libgo/go/runtime/traceback_gccgo.go
+++ b/libgo/go/runtime/traceback_gccgo.go
@@ -12,14 +12,6 @@
 	_ "unsafe" // for go:linkname
 )
 
-// For gccgo, use go:linkname to rename compiler-called functions to
-// themselves, so that the compiler will export them.
-// These are temporary for C runtime code to call.
-//go:linkname traceback runtime.traceback
-//go:linkname printtrace runtime.printtrace
-//go:linkname goroutineheader runtime.goroutineheader
-//go:linkname printcreatedby runtime.printcreatedby
-
 func printcreatedby(gp *g) {
 	// Show what created goroutine, except main goroutine (goid 1).
 	pc := gp.gopc
@@ -71,6 +63,7 @@
 	var locbuf [100]location
 	c := c_callers(skip+1, &locbuf[0], int32(len(locbuf)), false)
 	printtrace(locbuf[:c], getg())
+	printcreatedby(getg())
 }
 
 // printtrace prints a traceback from locbuf.
@@ -223,7 +216,7 @@
 			print("\tgoroutine running on other thread; stack unavailable\n")
 			printcreatedby(gp)
 		} else if readgstatus(gp)&^_Gscan == _Gsyscall {
-			print("\tgoroutine in C code; stack unavailable\n")
+			print("\tin C code; stack unavailable\n")
 			printcreatedby(gp)
 		} else {
 			gp.traceback = &tb
diff --git a/libgo/go/runtime/write_err_android.go b/libgo/go/runtime/write_err_android.go
index 748dec6..bf99b5f 100644
--- a/libgo/go/runtime/write_err_android.go
+++ b/libgo/go/runtime/write_err_android.go
@@ -144,7 +144,7 @@
 	//      hdr[3:7] sec unsigned uint32, little endian.
 	//      hdr[7:11] nsec unsigned uint32, little endian.
 	hdr[0] = 0 // LOG_ID_MAIN
-	sec, nsec := time_now()
+	sec, nsec := walltime()
 	packUint32(hdr[3:7], uint32(sec))
 	packUint32(hdr[7:11], uint32(nsec))
 
diff --git a/libgo/go/sort/example_test.go b/libgo/go/sort/example_test.go
index 980c0d0..f8d8491 100644
--- a/libgo/go/sort/example_test.go
+++ b/libgo/go/sort/example_test.go
@@ -41,3 +41,38 @@
 	// Output: By name: [{Alice 55} {Bob 75} {Gopher 7} {Vera 24}]
 	// By age: [{Gopher 7} {Vera 24} {Alice 55} {Bob 75}]
 }
+
+func ExampleSliceStable() {
+
+	people := []struct {
+		Name string
+		Age  int
+	}{
+		{"Alice", 25},
+		{"Elizabeth", 75},
+		{"Alice", 75},
+		{"Bob", 75},
+		{"Alice", 75},
+		{"Bob", 25},
+		{"Colin", 25},
+		{"Elizabeth", 25},
+	}
+
+	// Sort by name, preserving original order
+	sort.SliceStable(people, func(i, j int) bool { return people[i].Name < people[j].Name })
+	fmt.Println("By name:", people)
+
+	// Sort by age preserving name order
+	sort.SliceStable(people, func(i, j int) bool { return people[i].Age < people[j].Age })
+	fmt.Println("By age,name:", people)
+
+	// Output: By name: [{Alice 25} {Alice 75} {Alice 75} {Bob 75} {Bob 25} {Colin 25} {Elizabeth 75} {Elizabeth 25}]
+	// By age,name: [{Alice 25} {Bob 25} {Colin 25} {Elizabeth 25} {Alice 75} {Alice 75} {Bob 75} {Elizabeth 75}]
+}
+
+func ExampleStrings() {
+	s := []string{"Go", "Bravo", "Gopher", "Alpha", "Grin", "Delta"}
+	sort.Strings(s)
+	fmt.Println(s)
+	// Output: [Alpha Bravo Delta Go Gopher Grin]
+}
diff --git a/libgo/go/sort/genzfunc.go b/libgo/go/sort/genzfunc.go
index 6d2b471..3bb7691 100644
--- a/libgo/go/sort/genzfunc.go
+++ b/libgo/go/sort/genzfunc.go
@@ -115,6 +115,10 @@
 		// e.g. skip SelectorExpr (data.Less(..) calls)
 		return
 	}
+	// skip casts
+	if ident.Name == "int" || ident.Name == "uint" {
+		return
+	}
 	if len(ce.Args) < 1 {
 		return
 	}
diff --git a/libgo/go/sort/search.go b/libgo/go/sort/search.go
index b9640a4..fcff0f9 100644
--- a/libgo/go/sort/search.go
+++ b/libgo/go/sort/search.go
@@ -24,7 +24,7 @@
 //
 // For instance, given a slice data sorted in ascending order,
 // the call Search(len(data), func(i int) bool { return data[i] >= 23 })
-// returns the smallest index i such that data[i] >= 23.  If the caller
+// returns the smallest index i such that data[i] >= 23. If the caller
 // wants to find whether 23 is in the slice, it must test data[i] == 23
 // separately.
 //
@@ -61,7 +61,7 @@
 	// Invariant: f(i-1) == false, f(j) == true.
 	i, j := 0, n
 	for i < j {
-		h := i + (j-i)/2 // avoid overflow when computing h
+		h := int(uint(i+j) >> 1) // avoid overflow when computing h
 		// i ≤ h < j
 		if !f(h) {
 			i = h + 1 // preserves f(i-1) == false
diff --git a/libgo/go/sort/sort.go b/libgo/go/sort/sort.go
index 72d24ef..081b700 100644
--- a/libgo/go/sort/sort.go
+++ b/libgo/go/sort/sort.go
@@ -96,7 +96,7 @@
 }
 
 func doPivot(data Interface, lo, hi int) (midlo, midhi int) {
-	m := lo + (hi-lo)/2 // Written like this to avoid integer overflow.
+	m := int(uint(lo+hi) >> 1) // Written like this to avoid integer overflow.
 	if hi-lo > 40 {
 		// Tukey's ``Ninther,'' median of three medians of three.
 		s := (hi - lo) / 8
@@ -314,7 +314,8 @@
 // Sort is a convenience method.
 func (p IntSlice) Sort() { Sort(p) }
 
-// Float64Slice attaches the methods of Interface to []float64, sorting in increasing order.
+// Float64Slice attaches the methods of Interface to []float64, sorting in increasing order
+// (not-a-number values are treated as less than other values).
 type Float64Slice []float64
 
 func (p Float64Slice) Len() int           { return len(p) }
@@ -344,7 +345,8 @@
 // Ints sorts a slice of ints in increasing order.
 func Ints(a []int) { Sort(IntSlice(a)) }
 
-// Float64s sorts a slice of float64s in increasing order.
+// Float64s sorts a slice of float64s in increasing order
+// (not-a-number values are treated as less than other values).
 func Float64s(a []float64) { Sort(Float64Slice(a)) }
 
 // Strings sorts a slice of strings in increasing order.
@@ -353,7 +355,8 @@
 // IntsAreSorted tests whether a slice of ints is sorted in increasing order.
 func IntsAreSorted(a []int) bool { return IsSorted(IntSlice(a)) }
 
-// Float64sAreSorted tests whether a slice of float64s is sorted in increasing order.
+// Float64sAreSorted tests whether a slice of float64s is sorted in increasing order
+// (not-a-number values are treated as less than other values).
 func Float64sAreSorted(a []float64) bool { return IsSorted(Float64Slice(a)) }
 
 // StringsAreSorted tests whether a slice of strings is sorted in increasing order.
@@ -447,7 +450,7 @@
 		i := m
 		j := b
 		for i < j {
-			h := i + (j-i)/2
+			h := int(uint(i+j) >> 1)
 			if data.Less(h, a) {
 				i = h + 1
 			} else {
@@ -471,7 +474,7 @@
 		i := a
 		j := m
 		for i < j {
-			h := i + (j-i)/2
+			h := int(uint(i+j) >> 1)
 			if !data.Less(m, h) {
 				i = h + 1
 			} else {
@@ -485,7 +488,7 @@
 		return
 	}
 
-	mid := a + (b-a)/2
+	mid := int(uint(a+b) >> 1)
 	n := mid + m
 	var start, r int
 	if m > mid {
@@ -498,7 +501,7 @@
 	p := n - 1
 
 	for start < r {
-		c := start + (r-start)/2
+		c := int(uint(start+r) >> 1)
 		if !data.Less(p-c, c) {
 			start = c + 1
 		} else {
diff --git a/libgo/go/sort/zfuncversion.go b/libgo/go/sort/zfuncversion.go
index 7abb18a..99c95a2 100644
--- a/libgo/go/sort/zfuncversion.go
+++ b/libgo/go/sort/zfuncversion.go
@@ -70,7 +70,7 @@
 
 // Auto-generated variant of sort.go:doPivot
 func doPivot_func(data lessSwap, lo, hi int) (midlo, midhi int) {
-	m := lo + (hi-lo)/2
+	m := int(uint(lo+hi) >> 1)
 	if hi-lo > 40 {
 		s := (hi - lo) / 8
 		medianOfThree_func(data, lo, lo+s, lo+2*s)
@@ -189,7 +189,7 @@
 		i := m
 		j := b
 		for i < j {
-			h := i + (j-i)/2
+			h := int(uint(i+j) >> 1)
 			if data.Less(h, a) {
 				i = h + 1
 			} else {
@@ -205,7 +205,7 @@
 		i := a
 		j := m
 		for i < j {
-			h := i + (j-i)/2
+			h := int(uint(i+j) >> 1)
 			if !data.Less(m, h) {
 				i = h + 1
 			} else {
@@ -217,7 +217,7 @@
 		}
 		return
 	}
-	mid := a + (b-a)/2
+	mid := int(uint(a+b) >> 1)
 	n := mid + m
 	var start, r int
 	if m > mid {
@@ -229,7 +229,7 @@
 	}
 	p := n - 1
 	for start < r {
-		c := start + (r-start)/2
+		c := int(uint(start+r) >> 1)
 		if !data.Less(p-c, c) {
 			start = c + 1
 		} else {
diff --git a/libgo/go/strconv/atof_test.go b/libgo/go/strconv/atof_test.go
index 0a89c3e..3380b20 100644
--- a/libgo/go/strconv/atof_test.go
+++ b/libgo/go/strconv/atof_test.go
@@ -10,6 +10,7 @@
 	"reflect"
 	. "strconv"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 )
@@ -213,12 +214,17 @@
 }
 
 var (
+	atofOnce               sync.Once
 	atofRandomTests        []atofSimpleTest
 	benchmarksRandomBits   [1024]string
 	benchmarksRandomNormal [1024]string
 )
 
-func init() {
+func initAtof() {
+	atofOnce.Do(initAtofOnce)
+}
+
+func initAtofOnce() {
 	// The atof routines return NumErrors wrapping
 	// the error and the string. Convert the table above.
 	for i := range atoftests {
@@ -261,6 +267,7 @@
 }
 
 func testAtof(t *testing.T, opt bool) {
+	initAtof()
 	oldopt := SetOptimize(opt)
 	for i := 0; i < len(atoftests); i++ {
 		test := &atoftests[i]
@@ -306,6 +313,7 @@
 func TestAtofSlow(t *testing.T) { testAtof(t, false) }
 
 func TestAtofRandom(t *testing.T) {
+	initAtof()
 	for _, test := range atofRandomTests {
 		x, _ := ParseFloat(test.s, 64)
 		switch {
diff --git a/libgo/go/strconv/decimal.go b/libgo/go/strconv/decimal.go
index 957acd9..b580018 100644
--- a/libgo/go/strconv/decimal.go
+++ b/libgo/go/strconv/decimal.go
@@ -15,8 +15,8 @@
 	d     [800]byte // digits, big-endian representation
 	nd    int       // number of digits used
 	dp    int       // decimal point
-	neg   bool
-	trunc bool // discarded nonzero digits beyond d[:nd]
+	neg   bool      // negative flag
+	trunc bool      // discarded nonzero digits beyond d[:nd]
 }
 
 func (a *decimal) String() string {
diff --git a/libgo/go/strconv/itoa.go b/libgo/go/strconv/itoa.go
index f50d877..78527c8 100644
--- a/libgo/go/strconv/itoa.go
+++ b/libgo/go/strconv/itoa.go
@@ -4,10 +4,15 @@
 
 package strconv
 
+const fastSmalls = true // enable fast path for small integers
+
 // FormatUint returns the string representation of i in the given base,
 // for 2 <= base <= 36. The result uses the lower-case letters 'a' to 'z'
 // for digit values >= 10.
 func FormatUint(i uint64, base int) string {
+	if fastSmalls && i < nSmalls && base == 10 {
+		return small(int(i))
+	}
 	_, s := formatBits(nil, i, base, false, false)
 	return s
 }
@@ -16,6 +21,9 @@
 // for 2 <= base <= 36. The result uses the lower-case letters 'a' to 'z'
 // for digit values >= 10.
 func FormatInt(i int64, base int) string {
+	if fastSmalls && 0 <= i && i < nSmalls && base == 10 {
+		return small(int(i))
+	}
 	_, s := formatBits(nil, uint64(i), base, i < 0, false)
 	return s
 }
@@ -28,6 +36,9 @@
 // AppendInt appends the string form of the integer i,
 // as generated by FormatInt, to dst and returns the extended buffer.
 func AppendInt(dst []byte, i int64, base int) []byte {
+	if fastSmalls && 0 <= i && i < nSmalls && base == 10 {
+		return append(dst, small(int(i))...)
+	}
 	dst, _ = formatBits(dst, uint64(i), base, i < 0, true)
 	return dst
 }
@@ -35,13 +46,38 @@
 // AppendUint appends the string form of the unsigned integer i,
 // as generated by FormatUint, to dst and returns the extended buffer.
 func AppendUint(dst []byte, i uint64, base int) []byte {
+	if fastSmalls && i < nSmalls && base == 10 {
+		return append(dst, small(int(i))...)
+	}
 	dst, _ = formatBits(dst, i, base, false, true)
 	return dst
 }
 
-const (
-	digits = "0123456789abcdefghijklmnopqrstuvwxyz"
-)
+// small returns the string for an i with 0 <= i < nSmalls.
+func small(i int) string {
+	off := 0
+	if i < 10 {
+		off = 1
+	}
+	return smallsString[i*2+off : i*2+2]
+}
+
+const nSmalls = 100
+
+const smallsString = "00010203040506070809" +
+	"10111213141516171819" +
+	"20212223242526272829" +
+	"30313233343536373839" +
+	"40414243444546474849" +
+	"50515253545556575859" +
+	"60616263646566676869" +
+	"70717273747576777879" +
+	"80818283848586878889" +
+	"90919293949596979899"
+
+const host32bit = ^uint(0)>>32 == 0
+
+const digits = "0123456789abcdefghijklmnopqrstuvwxyz"
 
 var shifts = [len(digits) + 1]uint{
 	1 << 1: 1,
@@ -71,61 +107,84 @@
 	}
 
 	// convert bits
+	// We use uint values where we can because those will
+	// fit into a single register even on a 32bit machine.
 	if base == 10 {
 		// common case: use constants for / because
 		// the compiler can optimize it into a multiply+shift
 
-		if ^uintptr(0)>>32 == 0 {
-			for u > uint64(^uintptr(0)) {
+		if host32bit {
+			// convert the lower digits using 32bit operations
+			for u >= 1e9 {
+				// Avoid using r = a%b in addition to q = a/b
+				// since 64bit division and modulo operations
+				// are calculated by runtime functions on 32bit machines.
 				q := u / 1e9
-				us := uintptr(u - q*1e9) // us % 1e9 fits into a uintptr
-				for j := 9; j > 0; j-- {
-					i--
-					qs := us / 10
-					a[i] = byte(us - qs*10 + '0')
-					us = qs
+				us := uint(u - q*1e9) // u % 1e9 fits into a uint
+				for j := 4; j > 0; j-- {
+					is := us % 100 * 2
+					us /= 100
+					i -= 2
+					a[i+1] = smallsString[is+1]
+					a[i+0] = smallsString[is+0]
 				}
+
+				// us < 10, since it contains the last digit
+				// from the initial 9-digit us.
+				i--
+				a[i] = smallsString[us*2+1]
+
 				u = q
 			}
+			// u < 1e9
 		}
 
-		// u guaranteed to fit into a uintptr
-		us := uintptr(u)
-		for us >= 10 {
-			i--
-			q := us / 10
-			a[i] = byte(us - q*10 + '0')
-			us = q
+		// u guaranteed to fit into a uint
+		us := uint(u)
+		for us >= 100 {
+			is := us % 100 * 2
+			us /= 100
+			i -= 2
+			a[i+1] = smallsString[is+1]
+			a[i+0] = smallsString[is+0]
 		}
-		// u < 10
+
+		// us < 100
+		is := us * 2
 		i--
-		a[i] = byte(us + '0')
+		a[i] = smallsString[is+1]
+		if us >= 10 {
+			i--
+			a[i] = smallsString[is]
+		}
 
 	} else if s := shifts[base]; s > 0 {
 		// base is power of 2: use shifts and masks instead of / and %
 		b := uint64(base)
-		m := uintptr(b) - 1 // == 1<<s - 1
+		m := uint(base) - 1 // == 1<<s - 1
 		for u >= b {
 			i--
-			a[i] = digits[uintptr(u)&m]
+			a[i] = digits[uint(u)&m]
 			u >>= s
 		}
 		// u < base
 		i--
-		a[i] = digits[uintptr(u)]
-
+		a[i] = digits[uint(u)]
 	} else {
 		// general case
 		b := uint64(base)
 		for u >= b {
 			i--
+			// Avoid using r = a%b in addition to q = a/b
+			// since 64bit division and modulo operations
+			// are calculated by runtime functions on 32bit machines.
 			q := u / b
-			a[i] = digits[uintptr(u-q*b)]
+			a[i] = digits[uint(u-q*b)]
 			u = q
 		}
 		// u < base
 		i--
-		a[i] = digits[uintptr(u)]
+		a[i] = digits[uint(u)]
 	}
 
 	// add sign, if any
diff --git a/libgo/go/strconv/itoa_test.go b/libgo/go/strconv/itoa_test.go
index 48dc03e..89c2de6 100644
--- a/libgo/go/strconv/itoa_test.go
+++ b/libgo/go/strconv/itoa_test.go
@@ -126,10 +126,46 @@
 	}
 }
 
+var varlenUints = []struct {
+	in  uint64
+	out string
+}{
+	{1, "1"},
+	{12, "12"},
+	{123, "123"},
+	{1234, "1234"},
+	{12345, "12345"},
+	{123456, "123456"},
+	{1234567, "1234567"},
+	{12345678, "12345678"},
+	{123456789, "123456789"},
+	{1234567890, "1234567890"},
+	{12345678901, "12345678901"},
+	{123456789012, "123456789012"},
+	{1234567890123, "1234567890123"},
+	{12345678901234, "12345678901234"},
+	{123456789012345, "123456789012345"},
+	{1234567890123456, "1234567890123456"},
+	{12345678901234567, "12345678901234567"},
+	{123456789012345678, "123456789012345678"},
+	{1234567890123456789, "1234567890123456789"},
+	{12345678901234567890, "12345678901234567890"},
+}
+
+func TestFormatUintVarlen(t *testing.T) {
+	for _, test := range varlenUints {
+		s := FormatUint(test.in, 10)
+		if s != test.out {
+			t.Errorf("FormatUint(%v, 10) = %v want %v", test.in, s, test.out)
+		}
+	}
+}
+
 func BenchmarkFormatInt(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		for _, test := range itob64tests {
-			FormatInt(test.in, test.base)
+			s := FormatInt(test.in, test.base)
+			BenchSink += len(s)
 		}
 	}
 }
@@ -138,7 +174,8 @@
 	dst := make([]byte, 0, 30)
 	for i := 0; i < b.N; i++ {
 		for _, test := range itob64tests {
-			AppendInt(dst, test.in, test.base)
+			dst = AppendInt(dst[:0], test.in, test.base)
+			BenchSink += len(dst)
 		}
 	}
 }
@@ -146,7 +183,8 @@
 func BenchmarkFormatUint(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		for _, test := range uitob64tests {
-			FormatUint(test.in, test.base)
+			s := FormatUint(test.in, test.base)
+			BenchSink += len(s)
 		}
 	}
 }
@@ -155,7 +193,39 @@
 	dst := make([]byte, 0, 30)
 	for i := 0; i < b.N; i++ {
 		for _, test := range uitob64tests {
-			AppendUint(dst, test.in, test.base)
+			dst = AppendUint(dst[:0], test.in, test.base)
+			BenchSink += len(dst)
 		}
 	}
 }
+
+func BenchmarkFormatIntSmall(b *testing.B) {
+	const smallInt = 42
+	for i := 0; i < b.N; i++ {
+		s := FormatInt(smallInt, 10)
+		BenchSink += len(s)
+	}
+}
+
+func BenchmarkAppendIntSmall(b *testing.B) {
+	dst := make([]byte, 0, 30)
+	const smallInt = 42
+	for i := 0; i < b.N; i++ {
+		dst = AppendInt(dst[:0], smallInt, 10)
+		BenchSink += len(dst)
+	}
+}
+
+func BenchmarkAppendUintVarlen(b *testing.B) {
+	for _, test := range varlenUints {
+		b.Run(test.out, func(b *testing.B) {
+			dst := make([]byte, 0, 30)
+			for j := 0; j < b.N; j++ {
+				dst = AppendUint(dst[:0], test.in, 10)
+				BenchSink += len(dst)
+			}
+		})
+	}
+}
+
+var BenchSink int // make sure compiler cannot optimize away benchmarks
diff --git a/libgo/go/strconv/quote.go b/libgo/go/strconv/quote.go
index 76c5c2a..db57065 100644
--- a/libgo/go/strconv/quote.go
+++ b/libgo/go/strconv/quote.go
@@ -32,7 +32,7 @@
 			buf = append(buf, lowerhex[s[0]&0xF])
 			continue
 		}
-		buf = appendEscapedRune(buf, r, width, quote, ASCIIonly, graphicOnly)
+		buf = appendEscapedRune(buf, r, quote, ASCIIonly, graphicOnly)
 	}
 	buf = append(buf, quote)
 	return buf
@@ -43,12 +43,12 @@
 	if !utf8.ValidRune(r) {
 		r = utf8.RuneError
 	}
-	buf = appendEscapedRune(buf, r, utf8.RuneLen(r), quote, ASCIIonly, graphicOnly)
+	buf = appendEscapedRune(buf, r, quote, ASCIIonly, graphicOnly)
 	buf = append(buf, quote)
 	return buf
 }
 
-func appendEscapedRune(buf []byte, r rune, width int, quote byte, ASCIIonly, graphicOnly bool) []byte {
+func appendEscapedRune(buf []byte, r rune, quote byte, ASCIIonly, graphicOnly bool) []byte {
 	var runeTmp [utf8.UTFMax]byte
 	if r == rune(quote) || r == '\\' { // always backslashed
 		buf = append(buf, '\\')
diff --git a/libgo/go/strings/example_test.go b/libgo/go/strings/example_test.go
index 3f9d63b..e962152 100644
--- a/libgo/go/strings/example_test.go
+++ b/libgo/go/strings/example_test.go
@@ -23,6 +23,16 @@
 	// Output: Fields are: ["foo1" "bar2" "baz3"]
 }
 
+func ExampleCompare() {
+	fmt.Println(strings.Compare("a", "b"))
+	fmt.Println(strings.Compare("a", "a"))
+	fmt.Println(strings.Compare("b", "a"))
+	// Output:
+	// -1
+	// 0
+	// 1
+}
+
 func ExampleContains() {
 	fmt.Println(strings.Contains("seafood", "foo"))
 	fmt.Println(strings.Contains("seafood", "bar"))
@@ -47,6 +57,16 @@
 	// false
 }
 
+func ExampleContainsRune() {
+	// Finds whether a string contains a particular Unicode code point.
+	// The code point for the lowercase letter "a", for example, is 97.
+	fmt.Println(strings.ContainsRune("aardvark", 97))
+	fmt.Println(strings.ContainsRune("timeout", 97))
+	// Output:
+	// true
+	// false
+}
+
 func ExampleCount() {
 	fmt.Println(strings.Count("cheese", "e"))
 	fmt.Println(strings.Count("five", "")) // before & after each rune
@@ -109,6 +129,15 @@
 	// -1
 }
 
+func ExampleIndexByte() {
+	fmt.Println(strings.IndexByte("golang", 'g'))
+	fmt.Println(strings.IndexByte("gophers", 'h'))
+	fmt.Println(strings.IndexByte("golang", 'x'))
+	// Output:
+	// 0
+	// 3
+	// -1
+}
 func ExampleIndexRune() {
 	fmt.Println(strings.IndexRune("chicken", 'k'))
 	fmt.Println(strings.IndexRune("chicken", 'd'))
@@ -127,6 +156,16 @@
 	// -1
 }
 
+func ExampleLastIndexAny() {
+	fmt.Println(strings.LastIndexAny("go gopher", "go"))
+	fmt.Println(strings.LastIndexAny("go gopher", "rodent"))
+	fmt.Println(strings.LastIndexAny("go gopher", "fail"))
+	// Output:
+	// 4
+	// 8
+	// -1
+}
+
 func ExampleJoin() {
 	s := []string{"foo", "bar", "baz"}
 	fmt.Println(strings.Join(s, ", "))
@@ -195,6 +234,14 @@
 	// Output: ["Achtung! Achtung"]
 }
 
+func ExampleTrimFunc() {
+	f := func(c rune) bool {
+		return !unicode.IsLetter(c) && !unicode.IsNumber(c)
+	}
+	fmt.Printf("[%q]", strings.TrimFunc("  Achtung1! Achtung2,...", f))
+	// Output: ["Achtung1! Achtung2"]
+}
+
 func ExampleMap() {
 	rot13 := func(r rune) rune {
 		switch {
diff --git a/libgo/go/strings/replace_test.go b/libgo/go/strings/replace_test.go
index 77e48b9..34b5bad 100644
--- a/libgo/go/strings/replace_test.go
+++ b/libgo/go/strings/replace_test.go
@@ -540,3 +540,44 @@
 		Map(fn, str)
 	}
 }
+
+var mapdata = []struct{ name, data string }{
+	{"ASCII", "a b c d e f g h i j k l m n o p q r s t u v w x y z"},
+	{"Greek", "α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ ς σ τ υ φ χ ψ ω"},
+}
+
+func BenchmarkMap(b *testing.B) {
+	mapidentity := func(r rune) rune {
+		return r
+	}
+
+	b.Run("identity", func(b *testing.B) {
+		for _, md := range mapdata {
+			b.Run(md.name, func(b *testing.B) {
+				for i := 0; i < b.N; i++ {
+					Map(mapidentity, md.data)
+				}
+			})
+		}
+	})
+
+	mapchange := func(r rune) rune {
+		if 'a' <= r && r <= 'z' {
+			return r + 'A' - 'a'
+		}
+		if 'α' <= r && r <= 'ω' {
+			return r + 'Α' - 'α'
+		}
+		return r
+	}
+
+	b.Run("change", func(b *testing.B) {
+		for _, md := range mapdata {
+			b.Run(md.name, func(b *testing.B) {
+				for i := 0; i < b.N; i++ {
+					Map(mapchange, md.data)
+				}
+			})
+		}
+	})
+}
diff --git a/libgo/go/strings/strings.go b/libgo/go/strings/strings.go
index 60a281a..0c836c0 100644
--- a/libgo/go/strings/strings.go
+++ b/libgo/go/strings/strings.go
@@ -72,22 +72,20 @@
 	return hash, pow
 }
 
-// Count counts the number of non-overlapping instances of sep in s.
-// If sep is an empty string, Count returns 1 + the number of Unicode code points in s.
-func Count(s, sep string) int {
-	n := 0
-	// special cases
-	if len(sep) == 0 {
+// countGeneric implements Count.
+func countGeneric(s, substr string) int {
+	// special case
+	if len(substr) == 0 {
 		return utf8.RuneCountInString(s) + 1
 	}
-	offset := 0
+	n := 0
 	for {
-		i := Index(s[offset:], sep)
+		i := Index(s, substr)
 		if i == -1 {
 			return n
 		}
 		n++
-		offset += i + len(sep)
+		s = s[i+len(substr):]
 	}
 }
 
@@ -106,16 +104,16 @@
 	return IndexRune(s, r) >= 0
 }
 
-// LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
-func LastIndex(s, sep string) int {
-	n := len(sep)
+// LastIndex returns the index of the last instance of substr in s, or -1 if substr is not present in s.
+func LastIndex(s, substr string) int {
+	n := len(substr)
 	switch {
 	case n == 0:
 		return len(s)
 	case n == 1:
-		return LastIndexByte(s, sep[0])
+		return LastIndexByte(s, substr[0])
 	case n == len(s):
-		if sep == s {
+		if substr == s {
 			return 0
 		}
 		return -1
@@ -123,20 +121,20 @@
 		return -1
 	}
 	// Rabin-Karp search from the end of the string
-	hashsep, pow := hashStrRev(sep)
+	hashss, pow := hashStrRev(substr)
 	last := len(s) - n
 	var h uint32
 	for i := len(s) - 1; i >= last; i-- {
 		h = h*primeRK + uint32(s[i])
 	}
-	if h == hashsep && s[last:] == sep {
+	if h == hashss && s[last:] == substr {
 		return last
 	}
 	for i := last - 1; i >= 0; i-- {
 		h *= primeRK
 		h += uint32(s[i])
 		h -= pow * uint32(s[i+n])
-		if h == hashsep && s[i:i+n] == sep {
+		if h == hashss && s[i:i+n] == substr {
 			return i
 		}
 	}
@@ -240,61 +238,187 @@
 	if n < 0 {
 		n = Count(s, sep) + 1
 	}
-	c := sep[0]
-	start := 0
+
 	a := make([]string, n)
-	na := 0
-	for i := 0; i+len(sep) <= len(s) && na+1 < n; i++ {
-		if s[i] == c && (len(sep) == 1 || s[i:i+len(sep)] == sep) {
-			a[na] = s[start : i+sepSave]
-			na++
-			start = i + len(sep)
-			i += len(sep) - 1
+	n--
+	i := 0
+	for i < n {
+		m := Index(s, sep)
+		if m < 0 {
+			break
 		}
+		a[i] = s[:m+sepSave]
+		s = s[m+len(sep):]
+		i++
 	}
-	a[na] = s[start:]
-	return a[0 : na+1]
+	a[i] = s
+	return a[:i+1]
 }
 
 // SplitN slices s into substrings separated by sep and returns a slice of
 // the substrings between those separators.
-// If sep is empty, SplitN splits after each UTF-8 sequence.
+//
 // The count determines the number of substrings to return:
 //   n > 0: at most n substrings; the last substring will be the unsplit remainder.
 //   n == 0: the result is nil (zero substrings)
 //   n < 0: all substrings
+//
+// Edge cases for s and sep (for example, empty strings) are handled
+// as described in the documentation for Split.
 func SplitN(s, sep string, n int) []string { return genSplit(s, sep, 0, n) }
 
 // SplitAfterN slices s into substrings after each instance of sep and
 // returns a slice of those substrings.
-// If sep is empty, SplitAfterN splits after each UTF-8 sequence.
+//
 // The count determines the number of substrings to return:
 //   n > 0: at most n substrings; the last substring will be the unsplit remainder.
 //   n == 0: the result is nil (zero substrings)
 //   n < 0: all substrings
+//
+// Edge cases for s and sep (for example, empty strings) are handled
+// as described in the documentation for SplitAfter.
 func SplitAfterN(s, sep string, n int) []string {
 	return genSplit(s, sep, len(sep), n)
 }
 
 // Split slices s into all substrings separated by sep and returns a slice of
 // the substrings between those separators.
-// If sep is empty, Split splits after each UTF-8 sequence.
+//
+// If s does not contain sep and sep is not empty, Split returns a
+// slice of length 1 whose only element is s.
+//
+// If sep is empty, Split splits after each UTF-8 sequence. If both s
+// and sep are empty, Split returns an empty slice.
+//
 // It is equivalent to SplitN with a count of -1.
 func Split(s, sep string) []string { return genSplit(s, sep, 0, -1) }
 
 // SplitAfter slices s into all substrings after each instance of sep and
 // returns a slice of those substrings.
-// If sep is empty, SplitAfter splits after each UTF-8 sequence.
+//
+// If s does not contain sep and sep is not empty, SplitAfter returns
+// a slice of length 1 whose only element is s.
+//
+// If sep is empty, SplitAfter splits after each UTF-8 sequence. If
+// both s and sep are empty, SplitAfter returns an empty slice.
+//
 // It is equivalent to SplitAfterN with a count of -1.
 func SplitAfter(s, sep string) []string {
 	return genSplit(s, sep, len(sep), -1)
 }
 
+var asciiSpace = [256]uint8{'\t': 1, '\n': 1, '\v': 1, '\f': 1, '\r': 1, ' ': 1}
+
 // Fields splits the string s around each instance of one or more consecutive white space
 // characters, as defined by unicode.IsSpace, returning an array of substrings of s or an
 // empty list if s contains only white space.
 func Fields(s string) []string {
-	return FieldsFunc(s, unicode.IsSpace)
+	// First count the fields.
+	// This is an exact count if s is ASCII, otherwise it is an approximation.
+	n := 0
+	wasSpace := 1
+	// setBits is used to track which bits are set in the bytes of s.
+	setBits := uint8(0)
+	for i := 0; i < len(s); i++ {
+		r := s[i]
+		setBits |= r
+		isSpace := int(asciiSpace[r])
+		n += wasSpace & ^isSpace
+		wasSpace = isSpace
+	}
+
+	if setBits < utf8.RuneSelf { // ASCII fast path
+		a := make([]string, n)
+		na := 0
+		fieldStart := 0
+		i := 0
+		// Skip spaces in the front of the input.
+		for i < len(s) && asciiSpace[s[i]] != 0 {
+			i++
+		}
+		fieldStart = i
+		for i < len(s) {
+			if asciiSpace[s[i]] == 0 {
+				i++
+				continue
+			}
+			a[na] = s[fieldStart:i]
+			na++
+			i++
+			// Skip spaces in between fields.
+			for i < len(s) && asciiSpace[s[i]] != 0 {
+				i++
+			}
+			fieldStart = i
+		}
+		if fieldStart < len(s) { // Last field might end at EOF.
+			a[na] = s[fieldStart:]
+		}
+		return a
+	}
+
+	// Some runes in the input string are not ASCII.
+	// Same general approach as in the ASCII path but
+	// uses DecodeRuneInString and unicode.IsSpace if
+	// a non-ASCII rune needs to be decoded and checked
+	// if it corresponds to a space.
+	a := make([]string, 0, n)
+	fieldStart := 0
+	i := 0
+	// Skip spaces in the front of the input.
+	for i < len(s) {
+		if c := s[i]; c < utf8.RuneSelf {
+			if asciiSpace[c] == 0 {
+				break
+			}
+			i++
+		} else {
+			r, w := utf8.DecodeRuneInString(s[i:])
+			if !unicode.IsSpace(r) {
+				break
+			}
+			i += w
+		}
+	}
+	fieldStart = i
+	for i < len(s) {
+		if c := s[i]; c < utf8.RuneSelf {
+			if asciiSpace[c] == 0 {
+				i++
+				continue
+			}
+			a = append(a, s[fieldStart:i])
+			i++
+		} else {
+			r, w := utf8.DecodeRuneInString(s[i:])
+			if !unicode.IsSpace(r) {
+				i += w
+				continue
+			}
+			a = append(a, s[fieldStart:i])
+			i += w
+		}
+		// Skip spaces in between fields.
+		for i < len(s) {
+			if c := s[i]; c < utf8.RuneSelf {
+				if asciiSpace[c] == 0 {
+					break
+				}
+				i++
+			} else {
+				r, w := utf8.DecodeRuneInString(s[i:])
+				if !unicode.IsSpace(r) {
+					break
+				}
+				i += w
+			}
+		}
+		fieldStart = i
+	}
+	if fieldStart < len(s) { // Last field might end at EOF.
+		a = append(a, s[fieldStart:])
+	}
+	return a
 }
 
 // FieldsFunc splits the string s at each run of Unicode code points c satisfying f(c)
@@ -383,40 +507,71 @@
 	// In the worst case, the string can grow when mapped, making
 	// things unpleasant. But it's so rare we barge in assuming it's
 	// fine. It could also shrink but that falls out naturally.
-	maxbytes := len(s) // length of b
-	nbytes := 0        // number of bytes encoded in b
+
 	// The output buffer b is initialized on demand, the first
 	// time a character differs.
 	var b []byte
+	// nbytes is the number of bytes encoded in b.
+	var nbytes int
 
 	for i, c := range s {
 		r := mapping(c)
-		if b == nil {
-			if r == c {
-				continue
-			}
-			b = make([]byte, maxbytes)
-			nbytes = copy(b, s[:i])
+		if r == c {
+			continue
 		}
+
+		b = make([]byte, len(s)+utf8.UTFMax)
+		nbytes = copy(b, s[:i])
 		if r >= 0 {
-			wid := 1
-			if r >= utf8.RuneSelf {
-				wid = utf8.RuneLen(r)
+			if r <= utf8.RuneSelf {
+				b[nbytes] = byte(r)
+				nbytes++
+			} else {
+				nbytes += utf8.EncodeRune(b[nbytes:], r)
 			}
-			if nbytes+wid > maxbytes {
-				// Grow the buffer.
-				maxbytes = maxbytes*2 + utf8.UTFMax
-				nb := make([]byte, maxbytes)
-				copy(nb, b[0:nbytes])
-				b = nb
-			}
-			nbytes += utf8.EncodeRune(b[nbytes:maxbytes], r)
 		}
+
+		if c == utf8.RuneError {
+			// RuneError is the result of either decoding
+			// an invalid sequence or '\uFFFD'. Determine
+			// the correct number of bytes we need to advance.
+			_, w := utf8.DecodeRuneInString(s[i:])
+			i += w
+		} else {
+			i += utf8.RuneLen(c)
+		}
+
+		s = s[i:]
+		break
 	}
+
 	if b == nil {
 		return s
 	}
-	return string(b[0:nbytes])
+
+	for _, c := range s {
+		r := mapping(c)
+
+		// common case
+		if (0 <= r && r <= utf8.RuneSelf) && nbytes < len(b) {
+			b[nbytes] = byte(r)
+			nbytes++
+			continue
+		}
+
+		// b is not big enough or r is not a ASCII rune.
+		if r >= 0 {
+			if nbytes+utf8.UTFMax >= len(b) {
+				// Grow the buffer.
+				nb := make([]byte, 2*len(b))
+				copy(nb, b[:nbytes])
+				b = nb
+			}
+			nbytes += utf8.EncodeRune(b[nbytes:], r)
+		}
+	}
+
+	return string(b[:nbytes])
 }
 
 // Repeat returns a new string consisting of count copies of the string s.
@@ -561,17 +716,10 @@
 // truth==false, the sense of the predicate function is
 // inverted.
 func indexFunc(s string, f func(rune) bool, truth bool) int {
-	start := 0
-	for start < len(s) {
-		wid := 1
-		r := rune(s[start])
-		if r >= utf8.RuneSelf {
-			r, wid = utf8.DecodeRuneInString(s[start:])
-		}
+	for i, r := range s {
 		if f(r) == truth {
-			return start
+			return i
 		}
-		start += wid
 	}
 	return -1
 }
diff --git a/libgo/go/strings/strings_amd64.go b/libgo/go/strings/strings_amd64.go
index e55afd5..9648912 100644
--- a/libgo/go/strings/strings_amd64.go
+++ b/libgo/go/strings/strings_amd64.go
@@ -6,44 +6,46 @@
 
 package strings
 
+import "internal/cpu"
+
 //go:noescape
 
 // indexShortStr returns the index of the first instance of c in s, or -1 if c is not present in s.
 // indexShortStr requires 2 <= len(c) <= shortStringLen
-func indexShortStr(s, c string) int // ../runtime/asm_$GOARCH.s
-func supportAVX2() bool             // ../runtime/asm_$GOARCH.s
+func indexShortStr(s, c string) int  // ../runtime/asm_amd64.s
+func countByte(s string, c byte) int // ../runtime/asm_amd64.s
 
 var shortStringLen int
 
 func init() {
-	if supportAVX2() {
+	if cpu.X86.HasAVX2 {
 		shortStringLen = 63
 	} else {
 		shortStringLen = 31
 	}
 }
 
-// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
-func Index(s, sep string) int {
-	n := len(sep)
+// Index returns the index of the first instance of substr in s, or -1 if substr is not present in s.
+func Index(s, substr string) int {
+	n := len(substr)
 	switch {
 	case n == 0:
 		return 0
 	case n == 1:
-		return IndexByte(s, sep[0])
+		return IndexByte(s, substr[0])
 	case n == len(s):
-		if sep == s {
+		if substr == s {
 			return 0
 		}
 		return -1
 	case n > len(s):
 		return -1
 	case n <= shortStringLen:
-		// Use brute force when s and sep both are small
+		// Use brute force when s and substr both are small
 		if len(s) <= 64 {
-			return indexShortStr(s, sep)
+			return indexShortStr(s, substr)
 		}
-		c := sep[0]
+		c := substr[0]
 		i := 0
 		t := s[:len(s)-n+1]
 		fails := 0
@@ -57,7 +59,7 @@
 				}
 				i += o
 			}
-			if s[i:i+n] == sep {
+			if s[i:i+n] == substr {
 				return i
 			}
 			fails++
@@ -66,7 +68,7 @@
 			// Too many means more that 1 error per 8 characters.
 			// Allow some errors in the beginning.
 			if fails > (i+16)/8 {
-				r := indexShortStr(s[i:], sep)
+				r := indexShortStr(s[i:], substr)
 				if r >= 0 {
 					return r + i
 				}
@@ -76,12 +78,12 @@
 		return -1
 	}
 	// Rabin-Karp search
-	hashsep, pow := hashStr(sep)
+	hashss, pow := hashStr(substr)
 	var h uint32
 	for i := 0; i < n; i++ {
 		h = h*primeRK + uint32(s[i])
 	}
-	if h == hashsep && s[:n] == sep {
+	if h == hashss && s[:n] == substr {
 		return 0
 	}
 	for i := n; i < len(s); {
@@ -89,9 +91,18 @@
 		h += uint32(s[i])
 		h -= pow * uint32(s[i-n])
 		i++
-		if h == hashsep && s[i-n:i] == sep {
+		if h == hashss && s[i-n:i] == substr {
 			return i - n
 		}
 	}
 	return -1
 }
+
+// Count counts the number of non-overlapping instances of substr in s.
+// If substr is an empty string, Count returns 1 + the number of Unicode code points in s.
+func Count(s, substr string) int {
+	if len(substr) == 1 && cpu.X86.HasPOPCNT {
+		return countByte(s, byte(substr[0]))
+	}
+	return countGeneric(s, substr)
+}
diff --git a/libgo/go/strings/strings_generic.go b/libgo/go/strings/strings_generic.go
index a3ad515..9844201 100644
--- a/libgo/go/strings/strings_generic.go
+++ b/libgo/go/strings/strings_generic.go
@@ -9,16 +9,16 @@
 // TODO: implements short string optimization on non amd64 platforms
 // and get rid of strings_amd64.go
 
-// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
-func Index(s, sep string) int {
-	n := len(sep)
+// Index returns the index of the first instance of substr in s, or -1 if substr is not present in s.
+func Index(s, substr string) int {
+	n := len(substr)
 	switch {
 	case n == 0:
 		return 0
 	case n == 1:
-		return IndexByte(s, sep[0])
+		return IndexByte(s, substr[0])
 	case n == len(s):
-		if sep == s {
+		if substr == s {
 			return 0
 		}
 		return -1
@@ -26,12 +26,12 @@
 		return -1
 	}
 	// Rabin-Karp search
-	hashsep, pow := hashStr(sep)
+	hashss, pow := hashStr(substr)
 	var h uint32
 	for i := 0; i < n; i++ {
 		h = h*primeRK + uint32(s[i])
 	}
-	if h == hashsep && s[:n] == sep {
+	if h == hashss && s[:n] == substr {
 		return 0
 	}
 	for i := n; i < len(s); {
@@ -39,9 +39,15 @@
 		h += uint32(s[i])
 		h -= pow * uint32(s[i-n])
 		i++
-		if h == hashsep && s[i-n:i] == sep {
+		if h == hashss && s[i-n:i] == substr {
 			return i - n
 		}
 	}
 	return -1
 }
+
+// Count counts the number of non-overlapping instances of substr in s.
+// If substr is an empty string, Count returns 1 + the number of Unicode code points in s.
+func Count(s, substr string) int {
+	return countGeneric(s, substr)
+}
diff --git a/libgo/go/strings/strings_s390x.go b/libgo/go/strings/strings_s390x.go
index b47702f..b05fb2b 100644
--- a/libgo/go/strings/strings_s390x.go
+++ b/libgo/go/strings/strings_s390x.go
@@ -26,27 +26,27 @@
 	}
 }
 
-// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
-func Index(s, sep string) int {
-	n := len(sep)
+// Index returns the index of the first instance of substr in s, or -1 if substr is not present in s.
+func Index(s, substr string) int {
+	n := len(substr)
 	switch {
 	case n == 0:
 		return 0
 	case n == 1:
-		return IndexByte(s, sep[0])
+		return IndexByte(s, substr[0])
 	case n == len(s):
-		if sep == s {
+		if substr == s {
 			return 0
 		}
 		return -1
 	case n > len(s):
 		return -1
 	case n <= shortStringLen:
-		// Use brute force when s and sep both are small
+		// Use brute force when s and substr both are small
 		if len(s) <= 64 {
-			return indexShortStr(s, sep)
+			return indexShortStr(s, substr)
 		}
-		c := sep[0]
+		c := substr[0]
 		i := 0
 		t := s[:len(s)-n+1]
 		fails := 0
@@ -60,7 +60,7 @@
 				}
 				i += o
 			}
-			if s[i:i+n] == sep {
+			if s[i:i+n] == substr {
 				return i
 			}
 			fails++
@@ -69,7 +69,7 @@
 			// Too many means more that 1 error per 8 characters.
 			// Allow some errors in the beginning.
 			if fails > (i+16)/8 {
-				r := indexShortStr(s[i:], sep)
+				r := indexShortStr(s[i:], substr)
 				if r >= 0 {
 					return r + i
 				}
@@ -79,12 +79,12 @@
 		return -1
 	}
 	// Rabin-Karp search
-	hashsep, pow := hashStr(sep)
+	hashss, pow := hashStr(substr)
 	var h uint32
 	for i := 0; i < n; i++ {
 		h = h*primeRK + uint32(s[i])
 	}
-	if h == hashsep && s[:n] == sep {
+	if h == hashss && s[:n] == substr {
 		return 0
 	}
 	for i := n; i < len(s); {
@@ -92,9 +92,15 @@
 		h += uint32(s[i])
 		h -= pow * uint32(s[i-n])
 		i++
-		if h == hashsep && s[i-n:i] == sep {
+		if h == hashss && s[i-n:i] == substr {
 			return i - n
 		}
 	}
 	return -1
 }
+
+// Count counts the number of non-overlapping instances of substr in s.
+// If substr is an empty string, Count returns 1 + the number of Unicode code points in s.
+func Count(s, substr string) int {
+	return countGeneric(s, substr)
+}
diff --git a/libgo/go/strings/strings_test.go b/libgo/go/strings/strings_test.go
index 449fb50..0fddaf0 100644
--- a/libgo/go/strings/strings_test.go
+++ b/libgo/go/strings/strings_test.go
@@ -456,6 +456,7 @@
 	{"", []string{}},
 	{" ", []string{}},
 	{" \t ", []string{}},
+	{"\u2000", []string{}},
 	{"  abc  ", []string{"abc"}},
 	{"1 2 3 4", []string{"1", "2", "3", "4"}},
 	{"1  2  3  4", []string{"1", "2", "3", "4"}},
@@ -463,6 +464,9 @@
 	{"1\u20002\u20013\u20024", []string{"1", "2", "3", "4"}},
 	{"\u2000\u2001\u2002", []string{}},
 	{"\n™\t™\n", []string{"™", "™"}},
+	{"\n\u20001™2\u2000 \u2001 ™", []string{"1™2", "™"}},
+	{"\n1\uFFFD \uFFFD2\u20003\uFFFD4", []string{"1\uFFFD", "\uFFFD2", "3\uFFFD4"}},
+	{"1\xFF\u2000\xFF2\xFF \xFF", []string{"1\xFF", "\xFF2\xFF", "\xFF"}},
 	{faces, []string{faces}},
 }
 
@@ -629,6 +633,19 @@
 		(*reflect.StringHeader)(unsafe.Pointer(&m)).Data {
 		t.Error("unexpected copy during identity map")
 	}
+
+	// 7. Handle invalid UTF-8 sequence
+	replaceNotLatin := func(r rune) rune {
+		if unicode.Is(unicode.Latin, r) {
+			return r
+		}
+		return '?'
+	}
+	m = Map(replaceNotLatin, "Hello\255World")
+	expect = "Hello?World"
+	if m != expect {
+		t.Errorf("replace invalid sequence: expected %q got %q", expect, m)
+	}
 }
 
 func TestToUpper(t *testing.T) { runStringTests(t, ToUpper, "ToUpper", upperTests) }
@@ -1444,6 +1461,24 @@
 	}
 }
 
+func BenchmarkCountByte(b *testing.B) {
+	indexSizes := []int{10, 32, 4 << 10, 4 << 20, 64 << 20}
+	benchStr := Repeat(benchmarkString,
+		(indexSizes[len(indexSizes)-1]+len(benchmarkString)-1)/len(benchmarkString))
+	benchFunc := func(b *testing.B, benchStr string) {
+		b.SetBytes(int64(len(benchStr)))
+		for i := 0; i < b.N; i++ {
+			Count(benchStr, "=")
+		}
+	}
+	for _, size := range indexSizes {
+		b.Run(fmt.Sprintf("%d", size), func(b *testing.B) {
+			benchFunc(b, benchStr[:size])
+		})
+	}
+
+}
+
 var makeFieldsInput = func() string {
 	x := make([]byte, 1<<20)
 	// Input is ~10% space, ~10% 2-byte UTF-8, rest ASCII non-space.
@@ -1464,40 +1499,88 @@
 	return string(x)
 }
 
-var fieldsInput = makeFieldsInput()
+var makeFieldsInputASCII = func() string {
+	x := make([]byte, 1<<20)
+	// Input is ~10% space, rest ASCII non-space.
+	for i := range x {
+		if rand.Intn(10) == 0 {
+			x[i] = ' '
+		} else {
+			x[i] = 'x'
+		}
+	}
+	return string(x)
+}
+
+var stringdata = []struct{ name, data string }{
+	{"ASCII", makeFieldsInputASCII()},
+	{"Mixed", makeFieldsInput()},
+}
 
 func BenchmarkFields(b *testing.B) {
-	b.SetBytes(int64(len(fieldsInput)))
-	for i := 0; i < b.N; i++ {
-		Fields(fieldsInput)
+	for _, sd := range stringdata {
+		b.Run(sd.name, func(b *testing.B) {
+			for j := 1 << 4; j <= 1<<20; j <<= 4 {
+				b.Run(fmt.Sprintf("%d", j), func(b *testing.B) {
+					b.ReportAllocs()
+					b.SetBytes(int64(j))
+					data := sd.data[:j]
+					for i := 0; i < b.N; i++ {
+						Fields(data)
+					}
+				})
+			}
+		})
 	}
 }
 
 func BenchmarkFieldsFunc(b *testing.B) {
-	b.SetBytes(int64(len(fieldsInput)))
-	for i := 0; i < b.N; i++ {
-		FieldsFunc(fieldsInput, unicode.IsSpace)
+	for _, sd := range stringdata {
+		b.Run(sd.name, func(b *testing.B) {
+			for j := 1 << 4; j <= 1<<20; j <<= 4 {
+				b.Run(fmt.Sprintf("%d", j), func(b *testing.B) {
+					b.ReportAllocs()
+					b.SetBytes(int64(j))
+					data := sd.data[:j]
+					for i := 0; i < b.N; i++ {
+						FieldsFunc(data, unicode.IsSpace)
+					}
+				})
+			}
+		})
 	}
 }
 
-func BenchmarkSplit1(b *testing.B) {
+func BenchmarkSplitEmptySeparator(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		Split(benchInputHard, "")
 	}
 }
 
-func BenchmarkSplit2(b *testing.B) {
+func BenchmarkSplitSingleByteSeparator(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		Split(benchInputHard, "/")
 	}
 }
 
-func BenchmarkSplit3(b *testing.B) {
+func BenchmarkSplitMultiByteSeparator(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		Split(benchInputHard, "hello")
 	}
 }
 
+func BenchmarkSplitNSingleByteSeparator(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		SplitN(benchInputHard, "/", 10)
+	}
+}
+
+func BenchmarkSplitNMultiByteSeparator(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		SplitN(benchInputHard, "hello", 10)
+	}
+}
+
 func BenchmarkRepeat(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		Repeat("-", 80)
diff --git a/libgo/go/sync/atomic/atomic_test.go b/libgo/go/sync/atomic/atomic_test.go
index 6d0831c..17baccb 100644
--- a/libgo/go/sync/atomic/atomic_test.go
+++ b/libgo/go/sync/atomic/atomic_test.go
@@ -953,16 +953,20 @@
 	}
 }
 
+const arch32 = unsafe.Sizeof(uintptr(0)) == 4
+
 func hammerSwapUintptr64(uaddr *uint64, count int) {
 	// only safe when uintptr is 64-bit.
 	// not called on 32-bit systems.
-	addr := (*uintptr)(unsafe.Pointer(uaddr))
-	seed := int(uintptr(unsafe.Pointer(&count)))
-	for i := 0; i < count; i++ {
-		new := uintptr(seed+i)<<32 | uintptr(seed+i)<<32>>32
-		old := SwapUintptr(addr, new)
-		if old>>32 != old<<32>>32 {
-			panic(fmt.Sprintf("SwapUintptr is not atomic: %v", old))
+	if !arch32 {
+		addr := (*uintptr)(unsafe.Pointer(uaddr))
+		seed := int(uintptr(unsafe.Pointer(&count)))
+		for i := 0; i < count; i++ {
+			new := uintptr(seed+i)<<32 | uintptr(seed+i)<<32>>32
+			old := SwapUintptr(addr, new)
+			if old>>32 != old<<32>>32 {
+				panic(fmt.Sprintf("SwapUintptr is not atomic: %v", old))
+			}
 		}
 	}
 }
@@ -1116,8 +1120,6 @@
 
 func hammerStoreLoadUintptr(t *testing.T, paddr unsafe.Pointer) {
 	addr := (*uintptr)(paddr)
-	var test64 uint64 = 1 << 50
-	arch32 := uintptr(test64) == 0
 	v := LoadUintptr(addr)
 	new := v
 	if arch32 {
@@ -1144,8 +1146,6 @@
 
 func hammerStoreLoadPointer(t *testing.T, paddr unsafe.Pointer) {
 	addr := (*unsafe.Pointer)(paddr)
-	var test64 uint64 = 1 << 50
-	arch32 := uintptr(test64) == 0
 	v := uintptr(LoadPointer(addr))
 	new := v
 	if arch32 {
@@ -1398,7 +1398,7 @@
 
 	switch runtime.GOARCH {
 	default:
-		if unsafe.Sizeof(int(0)) != 4 {
+		if !arch32 {
 			t.Skip("test only runs on 32-bit systems")
 		}
 	case "amd64p32":
diff --git a/libgo/go/sync/atomic/doc.go b/libgo/go/sync/atomic/doc.go
index 302ff43..7c007d7 100644
--- a/libgo/go/sync/atomic/doc.go
+++ b/libgo/go/sync/atomic/doc.go
@@ -48,8 +48,8 @@
 // On non-Linux ARM, the 64-bit functions use instructions unavailable before the ARMv6k core.
 //
 // On both ARM and x86-32, it is the caller's responsibility to arrange for 64-bit
-// alignment of 64-bit words accessed atomically. The first word in a global
-// variable or in an allocated struct or slice can be relied upon to be
+// alignment of 64-bit words accessed atomically. The first word in a
+// variable or in an allocated struct, array, or slice can be relied upon to be
 // 64-bit aligned.
 
 // SwapInt32 atomically stores new into *addr and returns the previous *addr value.
diff --git a/libgo/go/sync/atomic/value.go b/libgo/go/sync/atomic/value.go
index 30abf72..1fc1f68 100644
--- a/libgo/go/sync/atomic/value.go
+++ b/libgo/go/sync/atomic/value.go
@@ -9,7 +9,6 @@
 )
 
 // A Value provides an atomic load and store of a consistently typed value.
-// Values can be created as part of other data structures.
 // The zero value for a Value returns nil from Load.
 // Once Store has been called, a Value must not be copied.
 //
diff --git a/libgo/go/sync/cond.go b/libgo/go/sync/cond.go
index c070d9d..14e2f6b 100644
--- a/libgo/go/sync/cond.go
+++ b/libgo/go/sync/cond.go
@@ -17,7 +17,6 @@
 // which must be held when changing the condition and
 // when calling the Wait method.
 //
-// A Cond can be created as part of other structures.
 // A Cond must not be copied after first use.
 type Cond struct {
 	noCopy noCopy
diff --git a/libgo/go/sync/export_test.go b/libgo/go/sync/export_test.go
index 6ed38da..669076e 100644
--- a/libgo/go/sync/export_test.go
+++ b/libgo/go/sync/export_test.go
@@ -7,3 +7,5 @@
 // Export for testing.
 var Runtime_Semacquire = runtime_Semacquire
 var Runtime_Semrelease = runtime_Semrelease
+var Runtime_procPin = runtime_procPin
+var Runtime_procUnpin = runtime_procUnpin
diff --git a/libgo/go/sync/map.go b/libgo/go/sync/map.go
new file mode 100644
index 0000000..083f4a5
--- /dev/null
+++ b/libgo/go/sync/map.go
@@ -0,0 +1,375 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+import (
+	"sync/atomic"
+	"unsafe"
+)
+
+// Map is a concurrent map with amortized-constant-time loads, stores, and deletes.
+// It is safe for multiple goroutines to call a Map's methods concurrently.
+//
+// It is optimized for use in concurrent loops with keys that are
+// stable over time, and either few steady-state stores, or stores
+// localized to one goroutine per key.
+//
+// For use cases that do not share these attributes, it will likely have
+// comparable or worse performance and worse type safety than an ordinary
+// map paired with a read-write mutex.
+//
+// The zero Map is valid and empty.
+//
+// A Map must not be copied after first use.
+type Map struct {
+	mu Mutex
+
+	// read contains the portion of the map's contents that are safe for
+	// concurrent access (with or without mu held).
+	//
+	// The read field itself is always safe to load, but must only be stored with
+	// mu held.
+	//
+	// Entries stored in read may be updated concurrently without mu, but updating
+	// a previously-expunged entry requires that the entry be copied to the dirty
+	// map and unexpunged with mu held.
+	read atomic.Value // readOnly
+
+	// dirty contains the portion of the map's contents that require mu to be
+	// held. To ensure that the dirty map can be promoted to the read map quickly,
+	// it also includes all of the non-expunged entries in the read map.
+	//
+	// Expunged entries are not stored in the dirty map. An expunged entry in the
+	// clean map must be unexpunged and added to the dirty map before a new value
+	// can be stored to it.
+	//
+	// If the dirty map is nil, the next write to the map will initialize it by
+	// making a shallow copy of the clean map, omitting stale entries.
+	dirty map[interface{}]*entry
+
+	// misses counts the number of loads since the read map was last updated that
+	// needed to lock mu to determine whether the key was present.
+	//
+	// Once enough misses have occurred to cover the cost of copying the dirty
+	// map, the dirty map will be promoted to the read map (in the unamended
+	// state) and the next store to the map will make a new dirty copy.
+	misses int
+}
+
+// readOnly is an immutable struct stored atomically in the Map.read field.
+type readOnly struct {
+	m       map[interface{}]*entry
+	amended bool // true if the dirty map contains some key not in m.
+}
+
+// expunged is an arbitrary pointer that marks entries which have been deleted
+// from the dirty map.
+var expunged = unsafe.Pointer(new(interface{}))
+
+// An entry is a slot in the map corresponding to a particular key.
+type entry struct {
+	// p points to the interface{} value stored for the entry.
+	//
+	// If p == nil, the entry has been deleted and m.dirty == nil.
+	//
+	// If p == expunged, the entry has been deleted, m.dirty != nil, and the entry
+	// is missing from m.dirty.
+	//
+	// Otherwise, the entry is valid and recorded in m.read.m[key] and, if m.dirty
+	// != nil, in m.dirty[key].
+	//
+	// An entry can be deleted by atomic replacement with nil: when m.dirty is
+	// next created, it will atomically replace nil with expunged and leave
+	// m.dirty[key] unset.
+	//
+	// An entry's associated value can be updated by atomic replacement, provided
+	// p != expunged. If p == expunged, an entry's associated value can be updated
+	// only after first setting m.dirty[key] = e so that lookups using the dirty
+	// map find the entry.
+	p unsafe.Pointer // *interface{}
+}
+
+func newEntry(i interface{}) *entry {
+	return &entry{p: unsafe.Pointer(&i)}
+}
+
+// Load returns the value stored in the map for a key, or nil if no
+// value is present.
+// The ok result indicates whether value was found in the map.
+func (m *Map) Load(key interface{}) (value interface{}, ok bool) {
+	read, _ := m.read.Load().(readOnly)
+	e, ok := read.m[key]
+	if !ok && read.amended {
+		m.mu.Lock()
+		// Avoid reporting a spurious miss if m.dirty got promoted while we were
+		// blocked on m.mu. (If further loads of the same key will not miss, it's
+		// not worth copying the dirty map for this key.)
+		read, _ = m.read.Load().(readOnly)
+		e, ok = read.m[key]
+		if !ok && read.amended {
+			e, ok = m.dirty[key]
+			// Regardless of whether the entry was present, record a miss: this key
+			// will take the slow path until the dirty map is promoted to the read
+			// map.
+			m.missLocked()
+		}
+		m.mu.Unlock()
+	}
+	if !ok {
+		return nil, false
+	}
+	return e.load()
+}
+
+func (e *entry) load() (value interface{}, ok bool) {
+	p := atomic.LoadPointer(&e.p)
+	if p == nil || p == expunged {
+		return nil, false
+	}
+	return *(*interface{})(p), true
+}
+
+// Store sets the value for a key.
+func (m *Map) Store(key, value interface{}) {
+	read, _ := m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok && e.tryStore(&value) {
+		return
+	}
+
+	m.mu.Lock()
+	read, _ = m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok {
+		if e.unexpungeLocked() {
+			// The entry was previously expunged, which implies that there is a
+			// non-nil dirty map and this entry is not in it.
+			m.dirty[key] = e
+		}
+		e.storeLocked(&value)
+	} else if e, ok := m.dirty[key]; ok {
+		e.storeLocked(&value)
+	} else {
+		if !read.amended {
+			// We're adding the first new key to the dirty map.
+			// Make sure it is allocated and mark the read-only map as incomplete.
+			m.dirtyLocked()
+			m.read.Store(readOnly{m: read.m, amended: true})
+		}
+		m.dirty[key] = newEntry(value)
+	}
+	m.mu.Unlock()
+}
+
+// tryStore stores a value if the entry has not been expunged.
+//
+// If the entry is expunged, tryStore returns false and leaves the entry
+// unchanged.
+func (e *entry) tryStore(i *interface{}) bool {
+	p := atomic.LoadPointer(&e.p)
+	if p == expunged {
+		return false
+	}
+	for {
+		if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) {
+			return true
+		}
+		p = atomic.LoadPointer(&e.p)
+		if p == expunged {
+			return false
+		}
+	}
+}
+
+// unexpungeLocked ensures that the entry is not marked as expunged.
+//
+// If the entry was previously expunged, it must be added to the dirty map
+// before m.mu is unlocked.
+func (e *entry) unexpungeLocked() (wasExpunged bool) {
+	return atomic.CompareAndSwapPointer(&e.p, expunged, nil)
+}
+
+// storeLocked unconditionally stores a value to the entry.
+//
+// The entry must be known not to be expunged.
+func (e *entry) storeLocked(i *interface{}) {
+	atomic.StorePointer(&e.p, unsafe.Pointer(i))
+}
+
+// LoadOrStore returns the existing value for the key if present.
+// Otherwise, it stores and returns the given value.
+// The loaded result is true if the value was loaded, false if stored.
+func (m *Map) LoadOrStore(key, value interface{}) (actual interface{}, loaded bool) {
+	// Avoid locking if it's a clean hit.
+	read, _ := m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok {
+		actual, loaded, ok := e.tryLoadOrStore(value)
+		if ok {
+			return actual, loaded
+		}
+	}
+
+	m.mu.Lock()
+	read, _ = m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok {
+		if e.unexpungeLocked() {
+			m.dirty[key] = e
+		}
+		actual, loaded, _ = e.tryLoadOrStore(value)
+	} else if e, ok := m.dirty[key]; ok {
+		actual, loaded, _ = e.tryLoadOrStore(value)
+		m.missLocked()
+	} else {
+		if !read.amended {
+			// We're adding the first new key to the dirty map.
+			// Make sure it is allocated and mark the read-only map as incomplete.
+			m.dirtyLocked()
+			m.read.Store(readOnly{m: read.m, amended: true})
+		}
+		m.dirty[key] = newEntry(value)
+		actual, loaded = value, false
+	}
+	m.mu.Unlock()
+
+	return actual, loaded
+}
+
+// tryLoadOrStore atomically loads or stores a value if the entry is not
+// expunged.
+//
+// If the entry is expunged, tryLoadOrStore leaves the entry unchanged and
+// returns with ok==false.
+func (e *entry) tryLoadOrStore(i interface{}) (actual interface{}, loaded, ok bool) {
+	p := atomic.LoadPointer(&e.p)
+	if p == expunged {
+		return nil, false, false
+	}
+	if p != nil {
+		return *(*interface{})(p), true, true
+	}
+
+	// Copy the interface after the first load to make this method more amenable
+	// to escape analysis: if we hit the "load" path or the entry is expunged, we
+	// shouldn't bother heap-allocating.
+	ic := i
+	for {
+		if atomic.CompareAndSwapPointer(&e.p, nil, unsafe.Pointer(&ic)) {
+			return i, false, true
+		}
+		p = atomic.LoadPointer(&e.p)
+		if p == expunged {
+			return nil, false, false
+		}
+		if p != nil {
+			return *(*interface{})(p), true, true
+		}
+	}
+}
+
+// Delete deletes the value for a key.
+func (m *Map) Delete(key interface{}) {
+	read, _ := m.read.Load().(readOnly)
+	e, ok := read.m[key]
+	if !ok && read.amended {
+		m.mu.Lock()
+		read, _ = m.read.Load().(readOnly)
+		e, ok = read.m[key]
+		if !ok && read.amended {
+			delete(m.dirty, key)
+		}
+		m.mu.Unlock()
+	}
+	if ok {
+		e.delete()
+	}
+}
+
+func (e *entry) delete() (hadValue bool) {
+	for {
+		p := atomic.LoadPointer(&e.p)
+		if p == nil || p == expunged {
+			return false
+		}
+		if atomic.CompareAndSwapPointer(&e.p, p, nil) {
+			return true
+		}
+	}
+}
+
+// Range calls f sequentially for each key and value present in the map.
+// If f returns false, range stops the iteration.
+//
+// Range does not necessarily correspond to any consistent snapshot of the Map's
+// contents: no key will be visited more than once, but if the value for any key
+// is stored or deleted concurrently, Range may reflect any mapping for that key
+// from any point during the Range call.
+//
+// Range may be O(N) with the number of elements in the map even if f returns
+// false after a constant number of calls.
+func (m *Map) Range(f func(key, value interface{}) bool) {
+	// We need to be able to iterate over all of the keys that were already
+	// present at the start of the call to Range.
+	// If read.amended is false, then read.m satisfies that property without
+	// requiring us to hold m.mu for a long time.
+	read, _ := m.read.Load().(readOnly)
+	if read.amended {
+		// m.dirty contains keys not in read.m. Fortunately, Range is already O(N)
+		// (assuming the caller does not break out early), so a call to Range
+		// amortizes an entire copy of the map: we can promote the dirty copy
+		// immediately!
+		m.mu.Lock()
+		read, _ = m.read.Load().(readOnly)
+		if read.amended {
+			read = readOnly{m: m.dirty}
+			m.read.Store(read)
+			m.dirty = nil
+			m.misses = 0
+		}
+		m.mu.Unlock()
+	}
+
+	for k, e := range read.m {
+		v, ok := e.load()
+		if !ok {
+			continue
+		}
+		if !f(k, v) {
+			break
+		}
+	}
+}
+
+func (m *Map) missLocked() {
+	m.misses++
+	if m.misses < len(m.dirty) {
+		return
+	}
+	m.read.Store(readOnly{m: m.dirty})
+	m.dirty = nil
+	m.misses = 0
+}
+
+func (m *Map) dirtyLocked() {
+	if m.dirty != nil {
+		return
+	}
+
+	read, _ := m.read.Load().(readOnly)
+	m.dirty = make(map[interface{}]*entry, len(read.m))
+	for k, e := range read.m {
+		if !e.tryExpungeLocked() {
+			m.dirty[k] = e
+		}
+	}
+}
+
+func (e *entry) tryExpungeLocked() (isExpunged bool) {
+	p := atomic.LoadPointer(&e.p)
+	for p == nil {
+		if atomic.CompareAndSwapPointer(&e.p, nil, expunged) {
+			return true
+		}
+		p = atomic.LoadPointer(&e.p)
+	}
+	return p == expunged
+}
diff --git a/libgo/go/sync/map_bench_test.go b/libgo/go/sync/map_bench_test.go
new file mode 100644
index 0000000..e6a8bad
--- /dev/null
+++ b/libgo/go/sync/map_bench_test.go
@@ -0,0 +1,215 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync_test
+
+import (
+	"fmt"
+	"reflect"
+	"sync"
+	"sync/atomic"
+	"testing"
+)
+
+type bench struct {
+	setup func(*testing.B, mapInterface)
+	perG  func(b *testing.B, pb *testing.PB, i int, m mapInterface)
+}
+
+func benchMap(b *testing.B, bench bench) {
+	for _, m := range [...]mapInterface{&DeepCopyMap{}, &RWMutexMap{}, &sync.Map{}} {
+		b.Run(fmt.Sprintf("%T", m), func(b *testing.B) {
+			m = reflect.New(reflect.TypeOf(m).Elem()).Interface().(mapInterface)
+			if bench.setup != nil {
+				bench.setup(b, m)
+			}
+
+			b.ResetTimer()
+
+			var i int64
+			b.RunParallel(func(pb *testing.PB) {
+				id := int(atomic.AddInt64(&i, 1) - 1)
+				bench.perG(b, pb, id*b.N, m)
+			})
+		})
+	}
+}
+
+func BenchmarkLoadMostlyHits(b *testing.B) {
+	const hits, misses = 1023, 1
+
+	benchMap(b, bench{
+		setup: func(_ *testing.B, m mapInterface) {
+			for i := 0; i < hits; i++ {
+				m.LoadOrStore(i, i)
+			}
+			// Prime the map to get it into a steady state.
+			for i := 0; i < hits*2; i++ {
+				m.Load(i % hits)
+			}
+		},
+
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			for ; pb.Next(); i++ {
+				m.Load(i % (hits + misses))
+			}
+		},
+	})
+}
+
+func BenchmarkLoadMostlyMisses(b *testing.B) {
+	const hits, misses = 1, 1023
+
+	benchMap(b, bench{
+		setup: func(_ *testing.B, m mapInterface) {
+			for i := 0; i < hits; i++ {
+				m.LoadOrStore(i, i)
+			}
+			// Prime the map to get it into a steady state.
+			for i := 0; i < hits*2; i++ {
+				m.Load(i % hits)
+			}
+		},
+
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			for ; pb.Next(); i++ {
+				m.Load(i % (hits + misses))
+			}
+		},
+	})
+}
+
+func BenchmarkLoadOrStoreBalanced(b *testing.B) {
+	const hits, misses = 128, 128
+
+	benchMap(b, bench{
+		setup: func(b *testing.B, m mapInterface) {
+			if _, ok := m.(*DeepCopyMap); ok {
+				b.Skip("DeepCopyMap has quadratic running time.")
+			}
+			for i := 0; i < hits; i++ {
+				m.LoadOrStore(i, i)
+			}
+			// Prime the map to get it into a steady state.
+			for i := 0; i < hits*2; i++ {
+				m.Load(i % hits)
+			}
+		},
+
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			for ; pb.Next(); i++ {
+				j := i % (hits + misses)
+				if j < hits {
+					if _, ok := m.LoadOrStore(j, i); !ok {
+						b.Fatalf("unexpected miss for %v", j)
+					}
+				} else {
+					if v, loaded := m.LoadOrStore(i, i); loaded {
+						b.Fatalf("failed to store %v: existing value %v", i, v)
+					}
+				}
+			}
+		},
+	})
+}
+
+func BenchmarkLoadOrStoreUnique(b *testing.B) {
+	benchMap(b, bench{
+		setup: func(b *testing.B, m mapInterface) {
+			if _, ok := m.(*DeepCopyMap); ok {
+				b.Skip("DeepCopyMap has quadratic running time.")
+			}
+		},
+
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			for ; pb.Next(); i++ {
+				m.LoadOrStore(i, i)
+			}
+		},
+	})
+}
+
+func BenchmarkLoadOrStoreCollision(b *testing.B) {
+	benchMap(b, bench{
+		setup: func(_ *testing.B, m mapInterface) {
+			m.LoadOrStore(0, 0)
+		},
+
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			for ; pb.Next(); i++ {
+				m.LoadOrStore(0, 0)
+			}
+		},
+	})
+}
+
+func BenchmarkRange(b *testing.B) {
+	const mapSize = 1 << 10
+
+	benchMap(b, bench{
+		setup: func(_ *testing.B, m mapInterface) {
+			for i := 0; i < mapSize; i++ {
+				m.Store(i, i)
+			}
+		},
+
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			for ; pb.Next(); i++ {
+				m.Range(func(_, _ interface{}) bool { return true })
+			}
+		},
+	})
+}
+
+// BenchmarkAdversarialAlloc tests performance when we store a new value
+// immediately whenever the map is promoted to clean and otherwise load a
+// unique, missing key.
+//
+// This forces the Load calls to always acquire the map's mutex.
+func BenchmarkAdversarialAlloc(b *testing.B) {
+	benchMap(b, bench{
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			var stores, loadsSinceStore int64
+			for ; pb.Next(); i++ {
+				m.Load(i)
+				if loadsSinceStore++; loadsSinceStore > stores {
+					m.LoadOrStore(i, stores)
+					loadsSinceStore = 0
+					stores++
+				}
+			}
+		},
+	})
+}
+
+// BenchmarkAdversarialDelete tests performance when we periodically delete
+// one key and add a different one in a large map.
+//
+// This forces the Load calls to always acquire the map's mutex and periodically
+// makes a full copy of the map despite changing only one entry.
+func BenchmarkAdversarialDelete(b *testing.B) {
+	const mapSize = 1 << 10
+
+	benchMap(b, bench{
+		setup: func(_ *testing.B, m mapInterface) {
+			for i := 0; i < mapSize; i++ {
+				m.Store(i, i)
+			}
+		},
+
+		perG: func(b *testing.B, pb *testing.PB, i int, m mapInterface) {
+			for ; pb.Next(); i++ {
+				m.Load(i)
+
+				if i%mapSize == 0 {
+					m.Range(func(k, _ interface{}) bool {
+						m.Delete(k)
+						return false
+					})
+					m.Store(i, i)
+				}
+			}
+		},
+	})
+}
diff --git a/libgo/go/sync/map_reference_test.go b/libgo/go/sync/map_reference_test.go
new file mode 100644
index 0000000..9f27b07
--- /dev/null
+++ b/libgo/go/sync/map_reference_test.go
@@ -0,0 +1,151 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync_test
+
+import (
+	"sync"
+	"sync/atomic"
+)
+
+// This file contains reference map implementations for unit-tests.
+
+// mapInterface is the interface Map implements.
+type mapInterface interface {
+	Load(interface{}) (interface{}, bool)
+	Store(key, value interface{})
+	LoadOrStore(key, value interface{}) (actual interface{}, loaded bool)
+	Delete(interface{})
+	Range(func(key, value interface{}) (shouldContinue bool))
+}
+
+// RWMutexMap is an implementation of mapInterface using a sync.RWMutex.
+type RWMutexMap struct {
+	mu    sync.RWMutex
+	dirty map[interface{}]interface{}
+}
+
+func (m *RWMutexMap) Load(key interface{}) (value interface{}, ok bool) {
+	m.mu.RLock()
+	value, ok = m.dirty[key]
+	m.mu.RUnlock()
+	return
+}
+
+func (m *RWMutexMap) Store(key, value interface{}) {
+	m.mu.Lock()
+	if m.dirty == nil {
+		m.dirty = make(map[interface{}]interface{})
+	}
+	m.dirty[key] = value
+	m.mu.Unlock()
+}
+
+func (m *RWMutexMap) LoadOrStore(key, value interface{}) (actual interface{}, loaded bool) {
+	m.mu.Lock()
+	actual, loaded = m.dirty[key]
+	if !loaded {
+		actual = value
+		if m.dirty == nil {
+			m.dirty = make(map[interface{}]interface{})
+		}
+		m.dirty[key] = value
+	}
+	m.mu.Unlock()
+	return actual, loaded
+}
+
+func (m *RWMutexMap) Delete(key interface{}) {
+	m.mu.Lock()
+	delete(m.dirty, key)
+	m.mu.Unlock()
+}
+
+func (m *RWMutexMap) Range(f func(key, value interface{}) (shouldContinue bool)) {
+	m.mu.RLock()
+	keys := make([]interface{}, 0, len(m.dirty))
+	for k := range m.dirty {
+		keys = append(keys, k)
+	}
+	m.mu.RUnlock()
+
+	for _, k := range keys {
+		v, ok := m.Load(k)
+		if !ok {
+			continue
+		}
+		if !f(k, v) {
+			break
+		}
+	}
+}
+
+// DeepCopyMap is an implementation of mapInterface using a Mutex and
+// atomic.Value.  It makes deep copies of the map on every write to avoid
+// acquiring the Mutex in Load.
+type DeepCopyMap struct {
+	mu    sync.Mutex
+	clean atomic.Value
+}
+
+func (m *DeepCopyMap) Load(key interface{}) (value interface{}, ok bool) {
+	clean, _ := m.clean.Load().(map[interface{}]interface{})
+	value, ok = clean[key]
+	return value, ok
+}
+
+func (m *DeepCopyMap) Store(key, value interface{}) {
+	m.mu.Lock()
+	dirty := m.dirty()
+	dirty[key] = value
+	m.clean.Store(dirty)
+	m.mu.Unlock()
+}
+
+func (m *DeepCopyMap) LoadOrStore(key, value interface{}) (actual interface{}, loaded bool) {
+	clean, _ := m.clean.Load().(map[interface{}]interface{})
+	actual, loaded = clean[key]
+	if loaded {
+		return actual, loaded
+	}
+
+	m.mu.Lock()
+	// Reload clean in case it changed while we were waiting on m.mu.
+	clean, _ = m.clean.Load().(map[interface{}]interface{})
+	actual, loaded = clean[key]
+	if !loaded {
+		dirty := m.dirty()
+		dirty[key] = value
+		actual = value
+		m.clean.Store(dirty)
+	}
+	m.mu.Unlock()
+	return actual, loaded
+}
+
+func (m *DeepCopyMap) Delete(key interface{}) {
+	m.mu.Lock()
+	dirty := m.dirty()
+	delete(dirty, key)
+	m.clean.Store(dirty)
+	m.mu.Unlock()
+}
+
+func (m *DeepCopyMap) Range(f func(key, value interface{}) (shouldContinue bool)) {
+	clean, _ := m.clean.Load().(map[interface{}]interface{})
+	for k, v := range clean {
+		if !f(k, v) {
+			break
+		}
+	}
+}
+
+func (m *DeepCopyMap) dirty() map[interface{}]interface{} {
+	clean, _ := m.clean.Load().(map[interface{}]interface{})
+	dirty := make(map[interface{}]interface{}, len(clean)+1)
+	for k, v := range clean {
+		dirty[k] = v
+	}
+	return dirty
+}
diff --git a/libgo/go/sync/map_test.go b/libgo/go/sync/map_test.go
new file mode 100644
index 0000000..b60a1c7
--- /dev/null
+++ b/libgo/go/sync/map_test.go
@@ -0,0 +1,170 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync_test
+
+import (
+	"math/rand"
+	"reflect"
+	"runtime"
+	"sync"
+	"testing"
+	"testing/quick"
+)
+
+type mapOp string
+
+const (
+	opLoad        = mapOp("Load")
+	opStore       = mapOp("Store")
+	opLoadOrStore = mapOp("LoadOrStore")
+	opDelete      = mapOp("Delete")
+)
+
+var mapOps = [...]mapOp{opLoad, opStore, opLoadOrStore, opDelete}
+
+// mapCall is a quick.Generator for calls on mapInterface.
+type mapCall struct {
+	op   mapOp
+	k, v interface{}
+}
+
+func (c mapCall) apply(m mapInterface) (interface{}, bool) {
+	switch c.op {
+	case opLoad:
+		return m.Load(c.k)
+	case opStore:
+		m.Store(c.k, c.v)
+		return nil, false
+	case opLoadOrStore:
+		return m.LoadOrStore(c.k, c.v)
+	case opDelete:
+		m.Delete(c.k)
+		return nil, false
+	default:
+		panic("invalid mapOp")
+	}
+}
+
+type mapResult struct {
+	value interface{}
+	ok    bool
+}
+
+func randValue(r *rand.Rand) interface{} {
+	b := make([]byte, r.Intn(4))
+	for i := range b {
+		b[i] = 'a' + byte(rand.Intn(26))
+	}
+	return string(b)
+}
+
+func (mapCall) Generate(r *rand.Rand, size int) reflect.Value {
+	c := mapCall{op: mapOps[rand.Intn(len(mapOps))], k: randValue(r)}
+	switch c.op {
+	case opStore, opLoadOrStore:
+		c.v = randValue(r)
+	}
+	return reflect.ValueOf(c)
+}
+
+func applyCalls(m mapInterface, calls []mapCall) (results []mapResult, final map[interface{}]interface{}) {
+	for _, c := range calls {
+		v, ok := c.apply(m)
+		results = append(results, mapResult{v, ok})
+	}
+
+	final = make(map[interface{}]interface{})
+	m.Range(func(k, v interface{}) bool {
+		final[k] = v
+		return true
+	})
+
+	return results, final
+}
+
+func applyMap(calls []mapCall) ([]mapResult, map[interface{}]interface{}) {
+	return applyCalls(new(sync.Map), calls)
+}
+
+func applyRWMutexMap(calls []mapCall) ([]mapResult, map[interface{}]interface{}) {
+	return applyCalls(new(RWMutexMap), calls)
+}
+
+func applyDeepCopyMap(calls []mapCall) ([]mapResult, map[interface{}]interface{}) {
+	return applyCalls(new(DeepCopyMap), calls)
+}
+
+func TestMapMatchesRWMutex(t *testing.T) {
+	if err := quick.CheckEqual(applyMap, applyRWMutexMap, nil); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestMapMatchesDeepCopy(t *testing.T) {
+	if err := quick.CheckEqual(applyMap, applyDeepCopyMap, nil); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestConcurrentRange(t *testing.T) {
+	const mapSize = 1 << 10
+
+	m := new(sync.Map)
+	for n := int64(1); n <= mapSize; n++ {
+		m.Store(n, int64(n))
+	}
+
+	done := make(chan struct{})
+	var wg sync.WaitGroup
+	defer func() {
+		close(done)
+		wg.Wait()
+	}()
+	for g := int64(runtime.GOMAXPROCS(0)); g > 0; g-- {
+		r := rand.New(rand.NewSource(g))
+		wg.Add(1)
+		go func(g int64) {
+			defer wg.Done()
+			for i := int64(0); ; i++ {
+				select {
+				case <-done:
+					return
+				default:
+				}
+				for n := int64(1); n < mapSize; n++ {
+					if r.Int63n(mapSize) == 0 {
+						m.Store(n, n*i*g)
+					} else {
+						m.Load(n)
+					}
+				}
+			}
+		}(g)
+	}
+
+	iters := 1 << 10
+	if testing.Short() {
+		iters = 16
+	}
+	for n := iters; n > 0; n-- {
+		seen := make(map[int64]bool, mapSize)
+
+		m.Range(func(ki, vi interface{}) bool {
+			k, v := ki.(int64), vi.(int64)
+			if v%k != 0 {
+				t.Fatalf("while Storing multiples of %v, Range saw value %v", k, v)
+			}
+			if seen[k] {
+				t.Fatalf("Range visited key %v twice", k)
+			}
+			seen[k] = true
+			return true
+		})
+
+		if len(seen) != mapSize {
+			t.Fatalf("Range visited %v elements of %v-element Map", len(seen), mapSize)
+		}
+	}
+}
diff --git a/libgo/go/sync/mutex.go b/libgo/go/sync/mutex.go
index 8c9366f..1232c62 100644
--- a/libgo/go/sync/mutex.go
+++ b/libgo/go/sync/mutex.go
@@ -19,8 +19,7 @@
 func throw(string) // provided by runtime
 
 // A Mutex is a mutual exclusion lock.
-// Mutexes can be created as part of other structures;
-// the zero value for a Mutex is an unlocked mutex.
+// The zero value for a Mutex is an unlocked mutex.
 //
 // A Mutex must not be copied after first use.
 type Mutex struct {
@@ -37,7 +36,34 @@
 const (
 	mutexLocked = 1 << iota // mutex is locked
 	mutexWoken
+	mutexStarving
 	mutexWaiterShift = iota
+
+	// Mutex fairness.
+	//
+	// Mutex can be in 2 modes of operations: normal and starvation.
+	// In normal mode waiters are queued in FIFO order, but a woken up waiter
+	// does not own the mutex and competes with new arriving goroutines over
+	// the ownership. New arriving goroutines have an advantage -- they are
+	// already running on CPU and there can be lots of them, so a woken up
+	// waiter has good chances of losing. In such case it is queued at front
+	// of the wait queue. If a waiter fails to acquire the mutex for more than 1ms,
+	// it switches mutex to the starvation mode.
+	//
+	// In starvation mode ownership of the mutex is directly handed off from
+	// the unlocking goroutine to the waiter at the front of the queue.
+	// New arriving goroutines don't try to acquire the mutex even if it appears
+	// to be unlocked, and don't try to spin. Instead they queue themselves at
+	// the tail of the wait queue.
+	//
+	// If a waiter receives ownership of the mutex and sees that either
+	// (1) it is the last waiter in the queue, or (2) it waited for less than 1 ms,
+	// it switches mutex back to normal operation mode.
+	//
+	// Normal mode has considerably better performance as a goroutine can acquire
+	// a mutex several times in a row even if there are blocked waiters.
+	// Starvation mode is important to prevent pathological cases of tail latency.
+	starvationThresholdNs = 1e6
 )
 
 // Lock locks m.
@@ -52,41 +78,86 @@
 		return
 	}
 
+	var waitStartTime int64
+	starving := false
 	awoke := false
 	iter := 0
+	old := m.state
 	for {
-		old := m.state
-		new := old | mutexLocked
-		if old&mutexLocked != 0 {
-			if runtime_canSpin(iter) {
-				// Active spinning makes sense.
-				// Try to set mutexWoken flag to inform Unlock
-				// to not wake other blocked goroutines.
-				if !awoke && old&mutexWoken == 0 && old>>mutexWaiterShift != 0 &&
-					atomic.CompareAndSwapInt32(&m.state, old, old|mutexWoken) {
-					awoke = true
-				}
-				runtime_doSpin()
-				iter++
-				continue
+		// Don't spin in starvation mode, ownership is handed off to waiters
+		// so we won't be able to acquire the mutex anyway.
+		if old&(mutexLocked|mutexStarving) == mutexLocked && runtime_canSpin(iter) {
+			// Active spinning makes sense.
+			// Try to set mutexWoken flag to inform Unlock
+			// to not wake other blocked goroutines.
+			if !awoke && old&mutexWoken == 0 && old>>mutexWaiterShift != 0 &&
+				atomic.CompareAndSwapInt32(&m.state, old, old|mutexWoken) {
+				awoke = true
 			}
-			new = old + 1<<mutexWaiterShift
+			runtime_doSpin()
+			iter++
+			old = m.state
+			continue
+		}
+		new := old
+		// Don't try to acquire starving mutex, new arriving goroutines must queue.
+		if old&mutexStarving == 0 {
+			new |= mutexLocked
+		}
+		if old&(mutexLocked|mutexStarving) != 0 {
+			new += 1 << mutexWaiterShift
+		}
+		// The current goroutine switches mutex to starvation mode.
+		// But if the mutex is currently unlocked, don't do the switch.
+		// Unlock expects that starving mutex has waiters, which will not
+		// be true in this case.
+		if starving && old&mutexLocked != 0 {
+			new |= mutexStarving
 		}
 		if awoke {
 			// The goroutine has been woken from sleep,
 			// so we need to reset the flag in either case.
 			if new&mutexWoken == 0 {
-				throw("sync: inconsistent mutex state")
+				panic("sync: inconsistent mutex state")
 			}
 			new &^= mutexWoken
 		}
 		if atomic.CompareAndSwapInt32(&m.state, old, new) {
-			if old&mutexLocked == 0 {
+			if old&(mutexLocked|mutexStarving) == 0 {
+				break // locked the mutex with CAS
+			}
+			// If we were already waiting before, queue at the front of the queue.
+			queueLifo := waitStartTime != 0
+			if waitStartTime == 0 {
+				waitStartTime = runtime_nanotime()
+			}
+			runtime_SemacquireMutex(&m.sema, queueLifo)
+			starving = starving || runtime_nanotime()-waitStartTime > starvationThresholdNs
+			old = m.state
+			if old&mutexStarving != 0 {
+				// If this goroutine was woken and mutex is in starvation mode,
+				// ownership was handed off to us but mutex is in somewhat
+				// inconsistent state: mutexLocked is not set and we are still
+				// accounted as waiter. Fix that.
+				if old&(mutexLocked|mutexWoken) != 0 || old>>mutexWaiterShift == 0 {
+					panic("sync: inconsistent mutex state")
+				}
+				delta := int32(mutexLocked - 1<<mutexWaiterShift)
+				if !starving || old>>mutexWaiterShift == 1 {
+					// Exit starvation mode.
+					// Critical to do it here and consider wait time.
+					// Starvation mode is so inefficient, that two goroutines
+					// can go lock-step infinitely once they switch mutex
+					// to starvation mode.
+					delta -= mutexStarving
+				}
+				atomic.AddInt32(&m.state, delta)
 				break
 			}
-			runtime_SemacquireMutex(&m.sema)
 			awoke = true
 			iter = 0
+		} else {
+			old = m.state
 		}
 	}
 
@@ -110,22 +181,33 @@
 	// Fast path: drop lock bit.
 	new := atomic.AddInt32(&m.state, -mutexLocked)
 	if (new+mutexLocked)&mutexLocked == 0 {
-		throw("sync: unlock of unlocked mutex")
+		panic("sync: unlock of unlocked mutex")
 	}
-
-	old := new
-	for {
-		// If there are no waiters or a goroutine has already
-		// been woken or grabbed the lock, no need to wake anyone.
-		if old>>mutexWaiterShift == 0 || old&(mutexLocked|mutexWoken) != 0 {
-			return
+	if new&mutexStarving == 0 {
+		old := new
+		for {
+			// If there are no waiters or a goroutine has already
+			// been woken or grabbed the lock, no need to wake anyone.
+			// In starvation mode ownership is directly handed off from unlocking
+			// goroutine to the next waiter. We are not part of this chain,
+			// since we did not observe mutexStarving when we unlocked the mutex above.
+			// So get off the way.
+			if old>>mutexWaiterShift == 0 || old&(mutexLocked|mutexWoken|mutexStarving) != 0 {
+				return
+			}
+			// Grab the right to wake someone.
+			new = (old - 1<<mutexWaiterShift) | mutexWoken
+			if atomic.CompareAndSwapInt32(&m.state, old, new) {
+				runtime_Semrelease(&m.sema, false)
+				return
+			}
+			old = m.state
 		}
-		// Grab the right to wake someone.
-		new = (old - 1<<mutexWaiterShift) | mutexWoken
-		if atomic.CompareAndSwapInt32(&m.state, old, new) {
-			runtime_Semrelease(&m.sema)
-			return
-		}
-		old = m.state
+	} else {
+		// Starving mode: handoff mutex ownership to the next waiter.
+		// Note: mutexLocked is not set, the waiter will set it after wakeup.
+		// But mutex is still considered locked if mutexStarving is set,
+		// so new coming goroutines won't acquire it.
+		runtime_Semrelease(&m.sema, true)
 	}
 }
diff --git a/libgo/go/sync/mutex_test.go b/libgo/go/sync/mutex_test.go
index 88dbccf..784471d 100644
--- a/libgo/go/sync/mutex_test.go
+++ b/libgo/go/sync/mutex_test.go
@@ -15,12 +15,13 @@
 	"strings"
 	. "sync"
 	"testing"
+	"time"
 )
 
 func HammerSemaphore(s *uint32, loops int, cdone chan bool) {
 	for i := 0; i < loops; i++ {
 		Runtime_Semacquire(s)
-		Runtime_Semrelease(s)
+		Runtime_Semrelease(s, false)
 	}
 	cdone <- true
 }
@@ -174,6 +175,38 @@
 	}
 }
 
+func TestMutexFairness(t *testing.T) {
+	var mu Mutex
+	stop := make(chan bool)
+	defer close(stop)
+	go func() {
+		for {
+			mu.Lock()
+			time.Sleep(100 * time.Microsecond)
+			mu.Unlock()
+			select {
+			case <-stop:
+				return
+			default:
+			}
+		}
+	}()
+	done := make(chan bool)
+	go func() {
+		for i := 0; i < 10; i++ {
+			time.Sleep(100 * time.Microsecond)
+			mu.Lock()
+			mu.Unlock()
+		}
+		done <- true
+	}()
+	select {
+	case <-done:
+	case <-time.After(10 * time.Second):
+		t.Fatalf("can't acquire Mutex in 10 seconds")
+	}
+}
+
 func BenchmarkMutexUncontended(b *testing.B) {
 	type PaddedMutex struct {
 		Mutex
diff --git a/libgo/go/sync/pool.go b/libgo/go/sync/pool.go
index 0acdbde..e54f917 100644
--- a/libgo/go/sync/pool.go
+++ b/libgo/go/sync/pool.go
@@ -54,11 +54,18 @@
 }
 
 // Local per-P Pool appendix.
-type poolLocal struct {
+type poolLocalInternal struct {
 	private interface{}   // Can be used only by the respective P.
 	shared  []interface{} // Can be used by any P.
 	Mutex                 // Protects shared.
-	pad     [128]byte     // Prevents false sharing.
+}
+
+type poolLocal struct {
+	poolLocalInternal
+
+	// Prevents false sharing on widespread platforms with
+	// 128 mod (cache line size) = 0 .
+	pad [128 - unsafe.Sizeof(poolLocalInternal{})%128]byte
 }
 
 // from runtime
@@ -241,7 +248,8 @@
 }
 
 func indexLocal(l unsafe.Pointer, i int) *poolLocal {
-	return &(*[1000000]poolLocal)(l)[i]
+	lp := unsafe.Pointer(uintptr(l) + uintptr(i)*unsafe.Sizeof(poolLocal{}))
+	return (*poolLocal)(lp)
 }
 
 // Implemented in runtime.
diff --git a/libgo/go/sync/pool_test.go b/libgo/go/sync/pool_test.go
index f92e181..dad2f99 100644
--- a/libgo/go/sync/pool_test.go
+++ b/libgo/go/sync/pool_test.go
@@ -23,6 +23,10 @@
 	if p.Get() != nil {
 		t.Fatal("expected empty")
 	}
+
+	// Make sure that the goroutine doesn't migrate to another P
+	// between Put and Get calls.
+	Runtime_procPin()
 	p.Put("a")
 	p.Put("b")
 	if g := p.Get(); g != "a" {
@@ -34,6 +38,7 @@
 	if g := p.Get(); g != nil {
 		t.Fatalf("got %#v; want nil", g)
 	}
+	Runtime_procUnpin()
 
 	p.Put("c")
 	debug.SetGCPercent(100) // to allow following GC to actually run
@@ -60,10 +65,16 @@
 	if v := p.Get(); v != 2 {
 		t.Fatalf("got %v; want 2", v)
 	}
+
+	// Make sure that the goroutine doesn't migrate to another P
+	// between Put and Get calls.
+	Runtime_procPin()
 	p.Put(42)
 	if v := p.Get(); v != 42 {
 		t.Fatalf("got %v; want 42", v)
 	}
+	Runtime_procUnpin()
+
 	if v := p.Get(); v != 3 {
 		t.Fatalf("got %v; want 3", v)
 	}
diff --git a/libgo/go/sync/runtime.go b/libgo/go/sync/runtime.go
index 4d22ce6..be16bcc 100644
--- a/libgo/go/sync/runtime.go
+++ b/libgo/go/sync/runtime.go
@@ -14,13 +14,15 @@
 func runtime_Semacquire(s *uint32)
 
 // SemacquireMutex is like Semacquire, but for profiling contended Mutexes.
-func runtime_SemacquireMutex(*uint32)
+// If lifo is true, queue waiter at the head of wait queue.
+func runtime_SemacquireMutex(s *uint32, lifo bool)
 
 // Semrelease atomically increments *s and notifies a waiting goroutine
 // if one is blocked in Semacquire.
 // It is intended as a simple wakeup primitive for use by the synchronization
 // library and should not be used directly.
-func runtime_Semrelease(s *uint32)
+// If handoff is true, pass count directly to the first waiter.
+func runtime_Semrelease(s *uint32, handoff bool)
 
 // Approximation of notifyList in runtime/sema.go. Size and alignment must
 // agree.
@@ -57,3 +59,5 @@
 
 // runtime_doSpin does active spinning.
 func runtime_doSpin()
+
+func runtime_nanotime() int64
diff --git a/libgo/go/sync/runtime_sema_test.go b/libgo/go/sync/runtime_sema_test.go
index a2382f4..a680847 100644
--- a/libgo/go/sync/runtime_sema_test.go
+++ b/libgo/go/sync/runtime_sema_test.go
@@ -18,7 +18,7 @@
 	b.RunParallel(func(pb *testing.PB) {
 		sem := new(PaddedSem)
 		for pb.Next() {
-			Runtime_Semrelease(&sem.sem)
+			Runtime_Semrelease(&sem.sem, false)
 			Runtime_Semacquire(&sem.sem)
 		}
 	})
@@ -44,7 +44,7 @@
 	b.RunParallel(func(pb *testing.PB) {
 		foo := 0
 		for pb.Next() {
-			Runtime_Semrelease(&sem)
+			Runtime_Semrelease(&sem, false)
 			if work {
 				for i := 0; i < 100; i++ {
 					foo *= 2
@@ -54,7 +54,7 @@
 			Runtime_Semacquire(&sem)
 		}
 		_ = foo
-		Runtime_Semrelease(&sem)
+		Runtime_Semrelease(&sem, false)
 	})
 }
 
diff --git a/libgo/go/sync/rwmutex.go b/libgo/go/sync/rwmutex.go
index 71064ee..cb2dfe1 100644
--- a/libgo/go/sync/rwmutex.go
+++ b/libgo/go/sync/rwmutex.go
@@ -10,18 +10,21 @@
 	"unsafe"
 )
 
+// There is a modified copy of this file in runtime/rwmutex.go.
+// If you make any changes here, see if you should make them there.
+
 // An RWMutex is a reader/writer mutual exclusion lock.
 // The lock can be held by an arbitrary number of readers or a single writer.
-// RWMutexes can be created as part of other structures;
-// the zero value for a RWMutex is an unlocked mutex.
+// The zero value for a RWMutex is an unlocked mutex.
 //
 // An RWMutex must not be copied after first use.
 //
-// If a goroutine holds a RWMutex for reading, it must not expect this or any
-// other goroutine to be able to also take the read lock until the first read
-// lock is released. In particular, this prohibits recursive read locking.
-// This is to ensure that the lock eventually becomes available;
-// a blocked Lock call excludes new readers from acquiring the lock.
+// If a goroutine holds a RWMutex for reading and another goroutine might
+// call Lock, no goroutine should expect to be able to acquire a read lock
+// until the initial read lock is released. In particular, this prohibits
+// recursive read locking. This is to ensure that the lock eventually becomes
+// available; a blocked Lock call excludes new readers from acquiring the
+// lock.
 type RWMutex struct {
 	w           Mutex  // held if there are pending writers
 	writerSem   uint32 // semaphore for writers to wait for completing readers
@@ -33,6 +36,10 @@
 const rwmutexMaxReaders = 1 << 30
 
 // RLock locks rw for reading.
+//
+// It should not be used for recursive read locking; a blocked Lock
+// call excludes new readers from acquiring the lock. See the
+// documentation on the RWMutex type.
 func (rw *RWMutex) RLock() {
 	if race.Enabled {
 		_ = rw.w.state
@@ -66,7 +73,7 @@
 		// A writer is pending.
 		if atomic.AddInt32(&rw.readerWait, -1) == 0 {
 			// The last reader unblocks the writer.
-			runtime_Semrelease(&rw.writerSem)
+			runtime_Semrelease(&rw.writerSem, false)
 		}
 	}
 	if race.Enabled {
@@ -119,7 +126,7 @@
 	}
 	// Unblock blocked readers, if any.
 	for i := 0; i < int(r); i++ {
-		runtime_Semrelease(&rw.readerSem)
+		runtime_Semrelease(&rw.readerSem, false)
 	}
 	// Allow other writers to proceed.
 	rw.w.Unlock()
diff --git a/libgo/go/sync/rwmutex_test.go b/libgo/go/sync/rwmutex_test.go
index 0436f97..9ee8864 100644
--- a/libgo/go/sync/rwmutex_test.go
+++ b/libgo/go/sync/rwmutex_test.go
@@ -14,6 +14,9 @@
 	"testing"
 )
 
+// There is a modified copy of this file in runtime/rwmutex_test.go.
+// If you make any changes here, see if you should make them there.
+
 func parallelReader(m *RWMutex, clocked, cunlock, cdone chan bool) {
 	m.RLock()
 	clocked <- true
diff --git a/libgo/go/sync/waitgroup.go b/libgo/go/sync/waitgroup.go
index b386e1f..f266f7c 100644
--- a/libgo/go/sync/waitgroup.go
+++ b/libgo/go/sync/waitgroup.go
@@ -91,11 +91,11 @@
 	// Reset waiters count to 0.
 	*statep = 0
 	for ; w != 0; w-- {
-		runtime_Semrelease(&wg.sema)
+		runtime_Semrelease(&wg.sema, false)
 	}
 }
 
-// Done decrements the WaitGroup counter.
+// Done decrements the WaitGroup counter by one.
 func (wg *WaitGroup) Done() {
 	wg.Add(-1)
 }
diff --git a/libgo/go/sync/waitgroup_test.go b/libgo/go/sync/waitgroup_test.go
index 8ec34fd..e3e3096 100644
--- a/libgo/go/sync/waitgroup_test.go
+++ b/libgo/go/sync/waitgroup_test.go
@@ -18,11 +18,11 @@
 	wg2.Add(n)
 	exited := make(chan bool, n)
 	for i := 0; i != n; i++ {
-		go func(i int) {
+		go func() {
 			wg1.Done()
 			wg2.Wait()
 			exited <- true
-		}(i)
+		}()
 	}
 	wg1.Wait()
 	for i := 0; i != n; i++ {
@@ -70,11 +70,8 @@
 
 func TestWaitGroupMisuse2(t *testing.T) {
 	knownRacy(t)
-	if testing.Short() {
-		t.Skip("skipping flaky test in short mode; see issue 11443")
-	}
-	if runtime.NumCPU() <= 2 {
-		t.Skip("NumCPU<=2, skipping: this test requires parallelism")
+	if runtime.NumCPU() <= 4 {
+		t.Skip("NumCPU<=4, skipping: this test requires parallelism")
 	}
 	defer func() {
 		err := recover()
@@ -86,24 +83,37 @@
 	}()
 	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(4))
 	done := make(chan interface{}, 2)
-	// The detection is opportunistically, so we want it to panic
+	// The detection is opportunistic, so we want it to panic
 	// at least in one run out of a million.
 	for i := 0; i < 1e6; i++ {
 		var wg WaitGroup
+		var here uint32
 		wg.Add(1)
 		go func() {
 			defer func() {
 				done <- recover()
 			}()
+			atomic.AddUint32(&here, 1)
+			for atomic.LoadUint32(&here) != 3 {
+				// spin
+			}
 			wg.Wait()
 		}()
 		go func() {
 			defer func() {
 				done <- recover()
 			}()
+			atomic.AddUint32(&here, 1)
+			for atomic.LoadUint32(&here) != 3 {
+				// spin
+			}
 			wg.Add(1) // This is the bad guy.
 			wg.Done()
 		}()
+		atomic.AddUint32(&here, 1)
+		for atomic.LoadUint32(&here) != 3 {
+			// spin
+		}
 		wg.Done()
 		for j := 0; j < 2; j++ {
 			if err := <-done; err != nil {
diff --git a/libgo/go/syscall/errors_plan9.go b/libgo/go/syscall/errors_plan9.go
index 6952562..74a5659 100644
--- a/libgo/go/syscall/errors_plan9.go
+++ b/libgo/go/syscall/errors_plan9.go
@@ -45,6 +45,7 @@
 	// what package os and others expect.
 	EACCES       = NewError("access permission denied")
 	EAFNOSUPPORT = NewError("address family not supported by protocol")
+	ESPIPE       = NewError("illegal seek")
 )
 
 // Notes
diff --git a/libgo/go/syscall/exec_bsd.go b/libgo/go/syscall/exec_bsd.go
index 80991ec..9115cf0 100644
--- a/libgo/go/syscall/exec_bsd.go
+++ b/libgo/go/syscall/exec_bsd.go
@@ -26,6 +26,7 @@
 // Implemented in runtime package.
 func runtime_BeforeFork()
 func runtime_AfterFork()
+func runtime_AfterForkInChild()
 
 // Fork, dup fd onto 0..len(fd), and exec(argv0, argvv, envv) in child.
 // If a dup or exec fails, write the errno error to pipe.
@@ -77,6 +78,8 @@
 
 	// Fork succeeded, now in child.
 
+	runtime_AfterForkInChild()
+
 	// Enable tracing if requested.
 	if sys.Ptrace {
 		err1 = raw_ptrace(_PTRACE_TRACEME, 0, nil, nil)
@@ -126,27 +129,24 @@
 	// User and groups
 	if cred := sys.Credential; cred != nil {
 		ngroups := len(cred.Groups)
-		if ngroups == 0 {
-			err2 := setgroups(0, nil)
-			if err2 == nil {
-				err1 = 0
-			} else {
-				err1 = err2.(Errno)
-			}
-		} else {
-			groups := make([]Gid_t, ngroups)
+		var groups *Gid_t
+		if ngroups > 0 {
+			gids := make([]Gid_t, ngroups)
 			for i, v := range cred.Groups {
-				groups[i] = Gid_t(v)
+				gids[i] = Gid_t(v)
 			}
-			err2 := setgroups(ngroups, &groups[0])
+			groups = &gids[0]
+		}
+		if !cred.NoSetGroups {
+			err2 := setgroups(ngroups, groups)
 			if err2 == nil {
 				err1 = 0
 			} else {
 				err1 = err2.(Errno)
 			}
-		}
-		if err1 != 0 {
-			goto childerror
+			if err1 != 0 {
+				goto childerror
+			}
 		}
 		err2 := Setgid(int(cred.Gid))
 		if err2 != nil {
@@ -255,17 +255,3 @@
 		raw_exit(253)
 	}
 }
-
-// Try to open a pipe with O_CLOEXEC set on both file descriptors.
-func forkExecPipe(p []int) error {
-	err := Pipe(p)
-	if err != nil {
-		return err
-	}
-	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
-	if err != nil {
-		return err
-	}
-	_, err = fcntl(p[1], F_SETFD, FD_CLOEXEC)
-	return err
-}
diff --git a/libgo/go/syscall/exec_freebsd.go b/libgo/go/syscall/exec_freebsd.go
new file mode 100644
index 0000000..4ed32c0
--- /dev/null
+++ b/libgo/go/syscall/exec_freebsd.go
@@ -0,0 +1,25 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+func forkExecPipe(p []int) error {
+	err := Pipe2(p, O_CLOEXEC)
+	if err == nil {
+		return nil
+	}
+
+	// FreeBSD 9 fallback.
+	// TODO: remove this for Go 1.10 per Issue 19072
+	err = Pipe(p)
+	if err != nil {
+		return err
+	}
+	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
+	if err != nil {
+		return err
+	}
+	_, err = fcntl(p[1], F_SETFD, FD_CLOEXEC)
+	return err
+}
diff --git a/libgo/go/syscall/exec_linux.go b/libgo/go/syscall/exec_linux.go
index 8d6467a..6e2f83e 100644
--- a/libgo/go/syscall/exec_linux.go
+++ b/libgo/go/syscall/exec_linux.go
@@ -13,6 +13,12 @@
 //sysnb	raw_prctl(option int, arg2 int, arg3 int, arg4 int, arg5 int) (ret int, err Errno)
 //prctl(option _C_int, arg2 _C_long, arg3 _C_long, arg4 _C_long, arg5 _C_long) _C_int
 
+//sysnb rawUnshare(flags int) (err Errno)
+//unshare(flags _C_int) _C_int
+
+//sysnb rawMount(source *byte, target *byte, fstype *byte, flags uintptr, data *byte) (err Errno)
+//mount(source *byte, target *byte, fstype *byte, flags _C_long, data *byte) _C_int
+
 // SysProcIDMap holds Container ID to Host ID mappings used for User Namespaces in Linux.
 // See user_namespaces(7).
 type SysProcIDMap struct {
@@ -42,11 +48,18 @@
 	// This parameter is no-op if GidMappings == nil. Otherwise for unprivileged
 	// users this should be set to false for mappings work.
 	GidMappingsEnableSetgroups bool
+	AmbientCaps                []uintptr // Ambient capabilities (Linux only)
 }
 
+var (
+	none  = [...]byte{'n', 'o', 'n', 'e', 0}
+	slash = [...]byte{'/', 0}
+)
+
 // Implemented in runtime package.
 func runtime_BeforeFork()
 func runtime_AfterFork()
+func runtime_AfterForkInChild()
 
 // Implemented in clone_linux.c
 func rawClone(flags _C_ulong, child_stack *byte, ptid *Pid_t, ctid *Pid_t, regs unsafe.Pointer) _C_long
@@ -62,16 +75,62 @@
 // functions that do not grow the stack.
 //go:norace
 func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (pid int, err Errno) {
+	// Set up and fork. This returns immediately in the parent or
+	// if there's an error.
+	r1, err1, p, locked := forkAndExecInChild1(argv0, argv, envv, chroot, dir, attr, sys, pipe)
+	if locked {
+		runtime_AfterFork()
+	}
+	if err1 != 0 {
+		return 0, err1
+	}
+
+	// parent; return PID
+	pid = int(r1)
+
+	if sys.UidMappings != nil || sys.GidMappings != nil {
+		Close(p[0])
+		err := writeUidGidMappings(pid, sys)
+		var err2 Errno
+		if err != nil {
+			err2 = err.(Errno)
+		}
+		RawSyscall(SYS_WRITE, uintptr(p[1]), uintptr(unsafe.Pointer(&err2)), unsafe.Sizeof(err2))
+		Close(p[1])
+	}
+
+	return pid, 0
+}
+
+// forkAndExecInChild1 implements the body of forkAndExecInChild up to
+// the parent's post-fork path. This is a separate function so we can
+// separate the child's and parent's stack frames if we're using
+// vfork.
+//
+// This is go:noinline because the point is to keep the stack frames
+// of this and forkAndExecInChild separate.
+//
+//go:noinline
+//go:norace
+func forkAndExecInChild1(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (r1 uintptr, err1 Errno, p [2]int, locked bool) {
+	// Defined in linux/prctl.h starting with Linux 4.3.
+	const (
+		PR_CAP_AMBIENT       = 0x2f
+		PR_CAP_AMBIENT_RAISE = 0x2
+	)
+
+	// vfork requires that the child not touch any of the parent's
+	// active stack frames. Hence, the child does all post-fork
+	// processing in this stack frame and never returns, while the
+	// parent returns immediately from this frame and does all
+	// post-fork processing in the outer frame.
 	// Declare all variables at top in case any
 	// declarations require heap allocation (e.g., err1).
 	var (
-		r1     uintptr
-		r2     _C_long
-		err1   Errno
 		err2   Errno
 		nextfd int
 		i      int
-		p      [2]int
+		r2     int
 	)
 
 	// Record parent PID so child can test if it has died.
@@ -94,39 +153,42 @@
 	// synchronizing writing of User ID/Group ID mappings.
 	if sys.UidMappings != nil || sys.GidMappings != nil {
 		if err := forkExecPipe(p[:]); err != nil {
-			return 0, err.(Errno)
+			err1 = err.(Errno)
+			return
 		}
 	}
 
 	// About to call fork.
 	// No more allocation or calls of non-assembly functions.
 	runtime_BeforeFork()
-	r2 = rawClone(_C_ulong(uintptr(SIGCHLD)|sys.Cloneflags), nil, nil, nil, unsafe.Pointer(nil))
+	locked = true
+	r2 = int(rawClone(_C_ulong(uintptr(SIGCHLD)|sys.Cloneflags), nil, nil, nil, unsafe.Pointer(nil)))
 	if r2 < 0 {
-		runtime_AfterFork()
-		return 0, GetErrno()
+		err1 = GetErrno()
 	}
-
 	if r2 != 0 {
-		// parent; return PID
-		runtime_AfterFork()
-		pid = int(r2)
-
-		if sys.UidMappings != nil || sys.GidMappings != nil {
-			Close(p[0])
-			err := writeUidGidMappings(pid, sys)
-			if err != nil {
-				err2 = err.(Errno)
-			}
-			RawSyscall(SYS_WRITE, uintptr(p[1]), uintptr(unsafe.Pointer(&err2)), unsafe.Sizeof(err2))
-			Close(p[1])
-		}
-
-		return pid, 0
+		// If we're in the parent, we must return immediately
+		// so we're not in the same stack frame as the child.
+		// This can at most use the return PC, which the child
+		// will not modify, and the results of
+		// rawVforkSyscall, which must have been written after
+		// the child was replaced.
+		r1 = uintptr(r2)
+		return
 	}
 
 	// Fork succeeded, now in child.
 
+	runtime_AfterForkInChild()
+
+	// Enable the "keep capabilities" flag to set ambient capabilities later.
+	if len(sys.AmbientCaps) > 0 {
+		_, _, err1 = RawSyscall6(SYS_PRCTL, PR_SET_KEEPCAPS, 1, 0, 0, 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
 	// Wait for User ID/Group ID mappings to be written.
 	if sys.UidMappings != nil || sys.GidMappings != nil {
 		if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(p[1]), 0, 0); err1 != 0 {
@@ -184,17 +246,30 @@
 		}
 	}
 
-	// Chroot
-	if chroot != nil {
-		err1 = raw_chroot(chroot)
+	// Unshare
+	if sys.Unshareflags != 0 {
+		err1 = rawUnshare(int(sys.Unshareflags))
 		if err1 != 0 {
 			goto childerror
 		}
+		// The unshare system call in Linux doesn't unshare mount points
+		// mounted with --shared. Systemd mounts / with --shared. For a
+		// long discussion of the pros and cons of this see debian bug 739593.
+		// The Go model of unsharing is more like Plan 9, where you ask
+		// to unshare and the namespaces are unconditionally unshared.
+		// To make this model work we must further mark / as MS_PRIVATE.
+		// This is what the standard unshare command does.
+		if sys.Unshareflags&CLONE_NEWNS == CLONE_NEWNS {
+			err1 = rawMount(&none[0], &slash[0], nil, MS_REC|MS_PRIVATE, nil)
+			if err1 != 0 {
+				goto childerror
+			}
+		}
 	}
 
-	// Unshare
-	if sys.Unshareflags != 0 {
-		_, _, err1 = RawSyscall(SYS_UNSHARE, sys.Unshareflags, 0, 0)
+	// Chroot
+	if chroot != nil {
+		err1 = raw_chroot(chroot)
 		if err1 != 0 {
 			goto childerror
 		}
@@ -207,10 +282,7 @@
 		if ngroups > 0 {
 			groups = unsafe.Pointer(&cred.Groups[0])
 		}
-		// Don't call setgroups in case of user namespace, gid mappings
-		// and disabled setgroups, because otherwise unprivileged user namespace
-		// will fail with any non-empty SysProcAttr.Credential.
-		if !(sys.GidMappings != nil && !sys.GidMappingsEnableSetgroups && ngroups == 0) {
+		if !(sys.GidMappings != nil && !sys.GidMappingsEnableSetgroups && ngroups == 0) && !cred.NoSetGroups {
 			err1 = raw_setgroups(ngroups, groups)
 			if err1 != 0 {
 				goto childerror
@@ -226,6 +298,13 @@
 		}
 	}
 
+	for _, c := range sys.AmbientCaps {
+		_, _, err1 = RawSyscall6(SYS_PRCTL, PR_CAP_AMBIENT, uintptr(PR_CAP_AMBIENT_RAISE), c, 0, 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
 	// Chdir
 	if dir != nil {
 		err1 = raw_chdir(dir)
@@ -321,7 +400,7 @@
 
 	// Set the controlling TTY to Ctty
 	if sys.Setctty {
-		_, err1 = raw_ioctl(sys.Ctty, TIOCSCTTY, 0)
+		_, err1 = raw_ioctl(sys.Ctty, TIOCSCTTY, sys.Ctty)
 		if err1 != 0 {
 			goto childerror
 		}
diff --git a/libgo/go/syscall/exec_linux_test.go b/libgo/go/syscall/exec_linux_test.go
index 7a4b571..114deec 100644
--- a/libgo/go/syscall/exec_linux_test.go
+++ b/libgo/go/syscall/exec_linux_test.go
@@ -7,12 +7,20 @@
 package syscall_test
 
 import (
+	"flag"
+	"fmt"
+	"internal/testenv"
+	"io"
 	"io/ioutil"
 	"os"
 	"os/exec"
+	"os/user"
+	"path/filepath"
+	"strconv"
 	"strings"
 	"syscall"
 	"testing"
+	"unsafe"
 )
 
 // Check if we are in a chroot by checking if the inode of / is
@@ -49,6 +57,14 @@
 			t.Skip("kernel prohibits user namespace in unprivileged process")
 		}
 	}
+	// On Centos 7 make sure they set the kernel parameter user_namespace=1
+	// See issue 16283 and 20796.
+	if _, err := os.Stat("/sys/module/user_namespace/parameters/enable"); err == nil {
+		buf, _ := ioutil.ReadFile("/sys/module/user_namespace/parameters/enabled")
+		if !strings.HasPrefix(string(buf), "Y") {
+			t.Skip("kernel doesn't support user namespaces")
+		}
+	}
 	// When running under the Go continuous build, skip tests for
 	// now when under Kubernetes. (where things are root but not quite)
 	// Both of these are our own environment variables.
@@ -174,6 +190,12 @@
 	}
 	out, err := cmd.CombinedOutput()
 	if err != nil {
+		if strings.Contains(err.Error(), "operation not permitted") {
+			// Issue 17206: despite all the checks above,
+			// this still reportedly fails for some users.
+			// (older kernels?). Just skip.
+			t.Skip("skipping due to permission error")
+		}
 		t.Fatalf("Cmd failed with err %v, output: %s", err, out)
 	}
 
@@ -205,9 +227,10 @@
 		t.Fatalf("Cmd failed with err %v, output: %s", err, out)
 	}
 	strOut := strings.TrimSpace(string(out))
-	expected := "uid=0(root) gid=0(root) groups=0(root)"
+	expected := "uid=0(root) gid=0(root)"
 	// Just check prefix because some distros reportedly output a
 	// context parameter; see https://golang.org/issue/16224.
+	// Alpine does not output groups; see https://golang.org/issue/19938.
 	if !strings.HasPrefix(strOut, expected) {
 		t.Errorf("id command output: %q, expected prefix: %q", strOut, expected)
 	}
@@ -245,6 +268,7 @@
 		"uid=0(root) gid=0(root) groups=0(root),65534(nobody)",
 		"uid=0(root) gid=0(root) groups=0(root),65534(nogroup)",
 		"uid=0(root) gid=0(root) groups=0(root),65534",
+		"uid=0(root) gid=0(root) groups=0(root),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody)", // Alpine; see https://golang.org/issue/19938
 	}
 	for _, e := range expected {
 		if strOut == e {
@@ -253,3 +277,282 @@
 	}
 	t.Errorf("id command output: %q, expected one of %q", strOut, expected)
 }
+
+// TestUnshareHelperProcess isn't a real test. It's used as a helper process
+// for TestUnshareMountNameSpace.
+func TestUnshareMountNameSpaceHelper(*testing.T) {
+	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
+		return
+	}
+	defer os.Exit(0)
+	if err := syscall.Mount("none", flag.Args()[0], "proc", 0, ""); err != nil {
+		fmt.Fprintf(os.Stderr, "unshare: mount %v failed: %v", os.Args, err)
+		os.Exit(2)
+	}
+}
+
+// Test for Issue 38471: unshare fails because systemd has forced / to be shared
+func TestUnshareMountNameSpace(t *testing.T) {
+	// Make sure we are running as root so we have permissions to use unshare
+	// and create a network namespace.
+	if os.Getuid() != 0 {
+		t.Skip("kernel prohibits unshare in unprivileged process, unless using user namespace")
+	}
+
+	// When running under the Go continuous build, skip tests for
+	// now when under Kubernetes. (where things are root but not quite)
+	// Both of these are our own environment variables.
+	// See Issue 12815.
+	if os.Getenv("GO_BUILDER_NAME") != "" && os.Getenv("IN_KUBERNETES") == "1" {
+		t.Skip("skipping test on Kubernetes-based builders; see Issue 12815")
+	}
+
+	d, err := ioutil.TempDir("", "unshare")
+	if err != nil {
+		t.Fatalf("tempdir: %v", err)
+	}
+
+	cmd := exec.Command(os.Args[0], "-test.run=TestUnshareMountNameSpaceHelper", d)
+	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
+	cmd.SysProcAttr = &syscall.SysProcAttr{Unshareflags: syscall.CLONE_NEWNS}
+
+	o, err := cmd.CombinedOutput()
+	if err != nil {
+		if strings.Contains(err.Error(), ": permission denied") {
+			t.Skipf("Skipping test (golang.org/issue/19698); unshare failed due to permissions: %s, %v", o, err)
+		}
+		t.Fatalf("unshare failed: %s, %v", o, err)
+	}
+
+	// How do we tell if the namespace was really unshared? It turns out
+	// to be simple: just try to remove the directory. If it's still mounted
+	// on the rm will fail with EBUSY. Then we have some cleanup to do:
+	// we must unmount it, then try to remove it again.
+
+	if err := os.Remove(d); err != nil {
+		t.Errorf("rmdir failed on %v: %v", d, err)
+		if err := syscall.Unmount(d, syscall.MNT_FORCE); err != nil {
+			t.Errorf("Can't unmount %v: %v", d, err)
+		}
+		if err := os.Remove(d); err != nil {
+			t.Errorf("rmdir after unmount failed on %v: %v", d, err)
+		}
+	}
+}
+
+// Test for Issue 20103: unshare fails when chroot is used
+func TestUnshareMountNameSpaceChroot(t *testing.T) {
+	// Make sure we are running as root so we have permissions to use unshare
+	// and create a network namespace.
+	if os.Getuid() != 0 {
+		t.Skip("kernel prohibits unshare in unprivileged process, unless using user namespace")
+	}
+
+	// When running under the Go continuous build, skip tests for
+	// now when under Kubernetes. (where things are root but not quite)
+	// Both of these are our own environment variables.
+	// See Issue 12815.
+	if os.Getenv("GO_BUILDER_NAME") != "" && os.Getenv("IN_KUBERNETES") == "1" {
+		t.Skip("skipping test on Kubernetes-based builders; see Issue 12815")
+	}
+
+	d, err := ioutil.TempDir("", "unshare")
+	if err != nil {
+		t.Fatalf("tempdir: %v", err)
+	}
+
+	// Since we are doing a chroot, we need the binary there,
+	// and it must be statically linked.
+	x := filepath.Join(d, "syscall.test")
+	cmd := exec.Command(testenv.GoToolPath(t), "test", "-c", "-o", x, "syscall")
+	cmd.Env = append(os.Environ(), "CGO_ENABLED=0")
+	if o, err := cmd.CombinedOutput(); err != nil {
+		t.Fatalf("Build of syscall in chroot failed, output %v, err %v", o, err)
+	}
+
+	cmd = exec.Command("/syscall.test", "-test.run=TestUnshareMountNameSpaceHelper", "/")
+	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
+	cmd.SysProcAttr = &syscall.SysProcAttr{Chroot: d, Unshareflags: syscall.CLONE_NEWNS}
+
+	o, err := cmd.CombinedOutput()
+	if err != nil {
+		if strings.Contains(err.Error(), ": permission denied") {
+			t.Skipf("Skipping test (golang.org/issue/19698); unshare failed due to permissions: %s, %v", o, err)
+		}
+		t.Fatalf("unshare failed: %s, %v", o, err)
+	}
+
+	// How do we tell if the namespace was really unshared? It turns out
+	// to be simple: just try to remove the executable. If it's still mounted
+	// on, the rm will fail. Then we have some cleanup to do:
+	// we must force unmount it, then try to remove it again.
+
+	if err := os.Remove(x); err != nil {
+		t.Errorf("rm failed on %v: %v", x, err)
+		if err := syscall.Unmount(d, syscall.MNT_FORCE); err != nil {
+			t.Fatalf("Can't unmount %v: %v", d, err)
+		}
+		if err := os.Remove(x); err != nil {
+			t.Fatalf("rm failed on %v: %v", x, err)
+		}
+	}
+
+	if err := os.Remove(d); err != nil {
+		t.Errorf("rmdir failed on %v: %v", d, err)
+	}
+}
+
+type capHeader struct {
+	version uint32
+	pid     int
+}
+
+type capData struct {
+	effective   uint32
+	permitted   uint32
+	inheritable uint32
+}
+
+const CAP_SYS_TIME = 25
+
+type caps struct {
+	hdr  capHeader
+	data [2]capData
+}
+
+func getCaps() (caps, error) {
+	var c caps
+
+	// Get capability version
+	if _, _, errno := syscall.Syscall(syscall.SYS_CAPGET, uintptr(unsafe.Pointer(&c.hdr)), uintptr(unsafe.Pointer(nil)), 0); errno != 0 {
+		return c, fmt.Errorf("SYS_CAPGET: %v", errno)
+	}
+
+	// Get current capabilities
+	if _, _, errno := syscall.Syscall(syscall.SYS_CAPGET, uintptr(unsafe.Pointer(&c.hdr)), uintptr(unsafe.Pointer(&c.data[0])), 0); errno != 0 {
+		return c, fmt.Errorf("SYS_CAPGET: %v", errno)
+	}
+
+	return c, nil
+}
+
+func mustSupportAmbientCaps(t *testing.T) {
+	var uname syscall.Utsname
+	if err := syscall.Uname(&uname); err != nil {
+		t.Fatalf("Uname: %v", err)
+	}
+	var buf [65]byte
+	for i, b := range uname.Release {
+		buf[i] = byte(b)
+	}
+	ver := string(buf[:])
+	if i := strings.Index(ver, "\x00"); i != -1 {
+		ver = ver[:i]
+	}
+	if strings.HasPrefix(ver, "2.") ||
+		strings.HasPrefix(ver, "3.") ||
+		strings.HasPrefix(ver, "4.1.") ||
+		strings.HasPrefix(ver, "4.2.") {
+		t.Skipf("kernel version %q predates required 4.3; skipping test", ver)
+	}
+}
+
+// TestAmbientCapsHelper isn't a real test. It's used as a helper process for
+// TestAmbientCaps.
+func TestAmbientCapsHelper(*testing.T) {
+	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
+		return
+	}
+	defer os.Exit(0)
+
+	caps, err := getCaps()
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(2)
+	}
+	if caps.data[0].effective&(1<<uint(CAP_SYS_TIME)) == 0 {
+		fmt.Fprintln(os.Stderr, "CAP_SYS_TIME unexpectedly not in the effective capability mask")
+		os.Exit(2)
+	}
+}
+
+func TestAmbientCaps(t *testing.T) {
+	// Make sure we are running as root so we have permissions to use unshare
+	// and create a network namespace.
+	if os.Getuid() != 0 {
+		t.Skip("kernel prohibits unshare in unprivileged process, unless using user namespace")
+	}
+	mustSupportAmbientCaps(t)
+
+	// When running under the Go continuous build, skip tests for
+	// now when under Kubernetes. (where things are root but not quite)
+	// Both of these are our own environment variables.
+	// See Issue 12815.
+	if os.Getenv("GO_BUILDER_NAME") != "" && os.Getenv("IN_KUBERNETES") == "1" {
+		t.Skip("skipping test on Kubernetes-based builders; see Issue 12815")
+	}
+
+	caps, err := getCaps()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Add CAP_SYS_TIME to the permitted and inheritable capability mask,
+	// otherwise we will not be able to add it to the ambient capability mask.
+	caps.data[0].permitted |= 1 << uint(CAP_SYS_TIME)
+	caps.data[0].inheritable |= 1 << uint(CAP_SYS_TIME)
+
+	if _, _, errno := syscall.Syscall(syscall.SYS_CAPSET, uintptr(unsafe.Pointer(&caps.hdr)), uintptr(unsafe.Pointer(&caps.data[0])), 0); errno != 0 {
+		t.Fatalf("SYS_CAPSET: %v", errno)
+	}
+
+	u, err := user.Lookup("nobody")
+	if err != nil {
+		t.Fatal(err)
+	}
+	uid, err := strconv.ParseInt(u.Uid, 0, 32)
+	if err != nil {
+		t.Fatal(err)
+	}
+	gid, err := strconv.ParseInt(u.Gid, 0, 32)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Copy the test binary to a temporary location which is readable by nobody.
+	f, err := ioutil.TempFile("", "gotest")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(f.Name())
+	defer f.Close()
+	e, err := os.Open(os.Args[0])
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer e.Close()
+	if _, err := io.Copy(f, e); err != nil {
+		t.Fatal(err)
+	}
+	if err := f.Chmod(0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := f.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	cmd := exec.Command(f.Name(), "-test.run=TestAmbientCapsHelper")
+	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Credential: &syscall.Credential{
+			Uid: uint32(uid),
+			Gid: uint32(gid),
+		},
+		AmbientCaps: []uintptr{CAP_SYS_TIME},
+	}
+	if err := cmd.Run(); err != nil {
+		t.Fatal(err.Error())
+	}
+}
diff --git a/libgo/go/syscall/exec_unix.go b/libgo/go/syscall/exec_unix.go
index f2bc741..8d83e91 100644
--- a/libgo/go/syscall/exec_unix.go
+++ b/libgo/go/syscall/exec_unix.go
@@ -163,9 +163,10 @@
 // Credential holds user and group identities to be assumed
 // by a child process started by StartProcess.
 type Credential struct {
-	Uid    uint32   // User ID.
-	Gid    uint32   // Group ID.
-	Groups []uint32 // Supplementary group IDs.
+	Uid         uint32   // User ID.
+	Gid         uint32   // Group ID.
+	Groups      []uint32 // Supplementary group IDs.
+	NoSetGroups bool     // If true, don't set supplementary groups
 }
 
 // ProcAttr holds attributes that will be applied to a new process started
@@ -292,6 +293,14 @@
 	return pid, 0, err
 }
 
+// Implemented in runtime package.
+func runtime_BeforeExec()
+func runtime_AfterExec()
+
+// execveSolaris is non-nil on Solaris, set to execve in exec_solaris.go; this
+// avoids a build dependency for other platforms.
+var execveSolaris func(path uintptr, argv uintptr, envp uintptr) (err Errno)
+
 // Exec invokes the execve(2) system call.
 func Exec(argv0 string, argv []string, envv []string) (err error) {
 	argv0p, err := BytePtrFromString(argv0)
@@ -306,6 +315,9 @@
 	if err != nil {
 		return err
 	}
+	runtime_BeforeExec()
+
 	err1 := raw_execve(argv0p, &argvp[0], &envvp[0])
+	runtime_AfterExec()
 	return Errno(err1)
 }
diff --git a/libgo/go/syscall/forkpipe_bsd.go b/libgo/go/syscall/forkpipe_bsd.go
new file mode 100644
index 0000000..d418072
--- /dev/null
+++ b/libgo/go/syscall/forkpipe_bsd.go
@@ -0,0 +1,20 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly netbsd openbsd
+
+package syscall
+
+func forkExecPipe(p []int) error {
+	err := Pipe(p)
+	if err != nil {
+		return err
+	}
+	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
+	if err != nil {
+		return err
+	}
+	_, err = fcntl(p[1], F_SETFD, FD_CLOEXEC)
+	return err
+}
diff --git a/libgo/go/syscall/net.go b/libgo/go/syscall/net.go
new file mode 100644
index 0000000..272d3af
--- /dev/null
+++ b/libgo/go/syscall/net.go
@@ -0,0 +1,34 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+// A RawConn is a raw network connection.
+type RawConn interface {
+	// Control invokes f on the underlying connection's file
+	// descriptor or handle.
+	// The file descriptor fd is guaranteed to remain valid while
+	// f executes but not after f returns.
+	Control(f func(fd uintptr)) error
+
+	// Read invokes f on the underlying connection's file
+	// descriptor or handle; f is expected to try to read from the
+	// file descriptor.
+	// If f returns true, Read returns. Otherwise Read blocks
+	// waiting for the connection to be ready for reading and
+	// tries again repeatedly.
+	// The file descriptor is guaranteed to remain valid while f
+	// executes but not after f returns.
+	Read(f func(fd uintptr) (done bool)) error
+
+	// Write is like Read but for writing.
+	Write(f func(fd uintptr) (done bool)) error
+}
+
+// Conn is implemented by some types in the net package to provide
+// access to the underlying file descriptor or handle.
+type Conn interface {
+	// SyscallConn returns a raw network connection.
+	SyscallConn() (RawConn, error)
+}
diff --git a/libgo/go/syscall/syscall.go b/libgo/go/syscall/syscall.go
index 91dfa9a..8415383 100644
--- a/libgo/go/syscall/syscall.go
+++ b/libgo/go/syscall/syscall.go
@@ -22,7 +22,10 @@
 // Go repository should be migrated to use the corresponding
 // package in the golang.org/x/sys repository. That is also where updates
 // required by new systems or versions should be applied.
-// See https://golang.org/s/go1.4-syscall for more information.
+// Signal, Errno and SysProcAttr are not yet available in
+// golang.org/x/sys and must still be referenced from the
+// syscall package. See https://golang.org/s/go1.4-syscall
+// for more information.
 //
 package syscall
 
@@ -102,11 +105,3 @@
 // Getpagesize is provided by the runtime.
 
 func Getpagesize() int
-
-// use is a no-op, but the compiler cannot see that it is.
-// Calling use(p) ensures that p is kept live until that point.
-// This was needed until Go 1.6 to call syscall.Syscall correctly.
-// As of Go 1.6 the compiler handles that case automatically.
-// The uses and definition of use can be removed early in the Go 1.7 cycle.
-//go:noescape
-func use(p unsafe.Pointer)
diff --git a/libgo/go/syscall/syscall_dragonfly.go b/libgo/go/syscall/syscall_dragonfly.go
index c2fc67f..3e6617c 100644
--- a/libgo/go/syscall/syscall_dragonfly.go
+++ b/libgo/go/syscall/syscall_dragonfly.go
@@ -1,4 +1,4 @@
-// Copyright 2009,2010 The Go Authors. All rights reserved.
+// Copyright 2009 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
@@ -15,7 +15,7 @@
 	if !ok {
 		return 0, false
 	}
-	return (16 + namlen + 1 + 7) & ^uint64(7), true
+	return (16 + namlen + 1 + 7) &^ 7, true
 }
 
 func direntNamlen(buf []byte) (uint64, bool) {
diff --git a/libgo/go/syscall/syscall_linux_386.go b/libgo/go/syscall/syscall_linux_386.go
index 591d3e1..9abcab9 100644
--- a/libgo/go/syscall/syscall_linux_386.go
+++ b/libgo/go/syscall/syscall_linux_386.go
@@ -22,3 +22,7 @@
 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
 	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
 }
+
+func rawVforkSyscall(trap, a1 uintptr) (r1 uintptr, err Errno) {
+	panic("not implemented")
+}
diff --git a/libgo/go/syscall/syscall_linux_amd64.go b/libgo/go/syscall/syscall_linux_amd64.go
index 609faed..8ee7cd7 100644
--- a/libgo/go/syscall/syscall_linux_amd64.go
+++ b/libgo/go/syscall/syscall_linux_amd64.go
@@ -23,3 +23,5 @@
 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
 	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
 }
+
+func rawVforkSyscall(trap, a1 uintptr) (r1 uintptr, err Errno)
diff --git a/libgo/go/syscall/syscall_linux_mipsx.go b/libgo/go/syscall/syscall_linux_mipsx.go
index 06dd1ea..1a15218 100644
--- a/libgo/go/syscall/syscall_linux_mipsx.go
+++ b/libgo/go/syscall/syscall_linux_mipsx.go
@@ -24,3 +24,7 @@
 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
 	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
 }
+
+func rawVforkSyscall(trap, a1 uintptr) (r1 uintptr, err Errno) {
+	panic("not implemented")
+}
diff --git a/libgo/go/syscall/syscall_linux_s390x.go b/libgo/go/syscall/syscall_linux_s390x.go
index 1767a6e..fa3bb30 100644
--- a/libgo/go/syscall/syscall_linux_s390x.go
+++ b/libgo/go/syscall/syscall_linux_s390x.go
@@ -46,3 +46,7 @@
 	}
 	return ptrace(PTRACE_POKEUSR_AREA, pid, uintptr(unsafe.Pointer(&parea)), 0)
 }
+
+func rawVforkSyscall(trap, a1 uintptr) (r1 uintptr, err Errno) {
+	panic("not implemented")
+}
diff --git a/libgo/go/syscall/syscall_unix_test.go b/libgo/go/syscall/syscall_unix_test.go
index 2f25d18..b1fe78d 100644
--- a/libgo/go/syscall/syscall_unix_test.go
+++ b/libgo/go/syscall/syscall_unix_test.go
@@ -78,12 +78,16 @@
 	}
 	if os.Getenv("GO_WANT_HELPER_PROCESS") == "" {
 		// parent
-		name := filepath.Join(os.TempDir(), "TestFcntlFlock")
+		tempDir, err := ioutil.TempDir("", "TestFcntlFlock")
+		if err != nil {
+			t.Fatalf("Failed to create temp dir: %v", err)
+		}
+		name := filepath.Join(tempDir, "TestFcntlFlock")
 		fd, err := syscall.Open(name, syscall.O_CREAT|syscall.O_RDWR|syscall.O_CLOEXEC, 0)
 		if err != nil {
 			t.Fatalf("Open failed: %v", err)
 		}
-		defer syscall.Unlink(name)
+		defer os.RemoveAll(tempDir)
 		defer syscall.Close(fd)
 		if err := syscall.Ftruncate(fd, 1<<20); err != nil {
 			t.Fatalf("Ftruncate(1<<20) failed: %v", err)
diff --git a/libgo/go/testing/benchmark.go b/libgo/go/testing/benchmark.go
index bcebb41..84005aa 100644
--- a/libgo/go/testing/benchmark.go
+++ b/libgo/go/testing/benchmark.go
@@ -47,6 +47,7 @@
 // affecting benchmark results.
 type B struct {
 	common
+	importPath       string // import path of the package containing the benchmark
 	context          *benchContext
 	N                int
 	previousN        int           // number of iterations in the previous run
@@ -233,9 +234,18 @@
 	return true
 }
 
+var labelsOnce sync.Once
+
 // run executes the benchmark in a separate goroutine, including all of its
 // subbenchmarks. b must not have subbenchmarks.
 func (b *B) run() BenchmarkResult {
+	labelsOnce.Do(func() {
+		fmt.Fprintf(b.w, "goos: %s\n", runtime.GOOS)
+		fmt.Fprintf(b.w, "goarch: %s\n", runtime.GOARCH)
+		if b.importPath != "" {
+			fmt.Fprintf(b.w, "pkg: %s\n", b.importPath)
+		}
+	})
 	if b.context != nil {
 		// Running go test --test.bench
 		b.context.processBench(b) // Must call doBench.
@@ -306,6 +316,7 @@
 	return (float64(r.Bytes) * float64(r.N) / 1e6) / r.T.Seconds()
 }
 
+// AllocsPerOp returns r.MemAllocs / r.N.
 func (r BenchmarkResult) AllocsPerOp() int64 {
 	if r.N <= 0 {
 		return 0
@@ -313,6 +324,7 @@
 	return int64(r.MemAllocs) / int64(r.N)
 }
 
+// AllocedBytesPerOp returns r.MemBytes / r.N.
 func (r BenchmarkResult) AllocedBytesPerOp() int64 {
 	if r.N <= 0 {
 		return 0
@@ -340,6 +352,7 @@
 	return fmt.Sprintf("%8d\t%s%s", r.N, ns, mb)
 }
 
+// MemString returns r.AllocedBytesPerOp and r.AllocsPerOp in the same format as 'go test'.
 func (r BenchmarkResult) MemString() string {
 	return fmt.Sprintf("%8d B/op\t%8d allocs/op",
 		r.AllocedBytesPerOp(), r.AllocsPerOp())
@@ -363,10 +376,10 @@
 // An internal function but exported because it is cross-package; part of the implementation
 // of the "go test" command.
 func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) {
-	runBenchmarks(matchString, benchmarks)
+	runBenchmarks("", matchString, benchmarks)
 }
 
-func runBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) bool {
+func runBenchmarks(importPath string, matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) bool {
 	// If no flag was specified, don't run benchmarks.
 	if len(*matchBenchmarks) == 0 {
 		return true
@@ -384,7 +397,7 @@
 	}
 	var bs []InternalBenchmark
 	for _, Benchmark := range benchmarks {
-		if _, matched := ctx.match.fullName(nil, Benchmark.Name); matched {
+		if _, matched, _ := ctx.match.fullName(nil, Benchmark.Name); matched {
 			bs = append(bs, Benchmark)
 			benchName := benchmarkName(Benchmark.Name, maxprocs)
 			if l := len(benchName) + ctx.extLen + 1; l > ctx.maxLen {
@@ -398,6 +411,7 @@
 			w:      os.Stdout,
 			chatty: *chatty,
 		},
+		importPath: importPath,
 		benchFunc: func(b *B) {
 			for _, Benchmark := range bs {
 				b.Run(Benchmark.Name, Benchmark.F)
@@ -462,7 +476,7 @@
 // least once will not be measured itself and will be called once with N=1.
 //
 // Run may be called simultaneously from multiple goroutines, but all such
-// calls must happen before the outer benchmark function for b returns.
+// calls must return before the outer benchmark function for b returns.
 func (b *B) Run(name string, f func(b *B)) bool {
 	// Since b has subbenchmarks, we will no longer run it as a benchmark itself.
 	// Release the lock and acquire it on exit to ensure locks stay paired.
@@ -470,9 +484,9 @@
 	benchmarkLock.Unlock()
 	defer benchmarkLock.Lock()
 
-	benchName, ok := b.name, true
+	benchName, ok, partial := b.name, true, false
 	if b.context != nil {
-		benchName, ok = b.context.match.fullName(&b.common, name)
+		benchName, ok, partial = b.context.match.fullName(&b.common, name)
 	}
 	if !ok {
 		return true
@@ -486,9 +500,15 @@
 			w:      b.w,
 			chatty: b.chatty,
 		},
-		benchFunc: f,
-		benchTime: b.benchTime,
-		context:   b.context,
+		importPath: b.importPath,
+		benchFunc:  f,
+		benchTime:  b.benchTime,
+		context:    b.context,
+	}
+	if partial {
+		// Partial name match, like -bench=X/Y matching BenchmarkX.
+		// Only process sub-benchmarks, if any.
+		atomic.StoreInt32(&sub.hasSub, 1)
 	}
 	if sub.run1() {
 		sub.run()
@@ -634,10 +654,10 @@
 		benchFunc: f,
 		benchTime: *benchTime,
 	}
-	if !b.run1() {
-		return BenchmarkResult{}
+	if b.run1() {
+		b.run()
 	}
-	return b.run()
+	return b.result
 }
 
 type discard struct{}
diff --git a/libgo/go/testing/helper_test.go b/libgo/go/testing/helper_test.go
new file mode 100644
index 0000000..f5cb27c
--- /dev/null
+++ b/libgo/go/testing/helper_test.go
@@ -0,0 +1,70 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package testing
+
+import (
+	"bytes"
+	"regexp"
+	"strings"
+)
+
+func TestTBHelper(t *T) {
+	var buf bytes.Buffer
+	ctx := newTestContext(1, newMatcher(regexp.MatchString, "", ""))
+	t1 := &T{
+		common: common{
+			signal: make(chan bool),
+			w:      &buf,
+		},
+		context: ctx,
+	}
+	t1.Run("Test", testHelper)
+
+	want := `--- FAIL: Test (?s)
+helperfuncs_test.go:12: 0
+helperfuncs_test.go:33: 1
+helperfuncs_test.go:21: 2
+helperfuncs_test.go:35: 3
+helperfuncs_test.go:42: 4
+helperfuncs_test.go:47: 5
+--- FAIL: Test/sub (?s)
+helperfuncs_test.go:50: 6
+helperfuncs_test.go:21: 7
+helperfuncs_test.go:53: 8
+`
+	lines := strings.Split(buf.String(), "\n")
+	durationRE := regexp.MustCompile(`\(.*\)$`)
+	for i, line := range lines {
+		line = strings.TrimSpace(line)
+		line = durationRE.ReplaceAllString(line, "(?s)")
+		lines[i] = line
+	}
+	got := strings.Join(lines, "\n")
+	if got != want {
+		t.Errorf("got output:\n\n%s\nwant:\n\n%s", got, want)
+	}
+}
+
+func TestTBHelperParallel(t *T) {
+	var buf bytes.Buffer
+	ctx := newTestContext(1, newMatcher(regexp.MatchString, "", ""))
+	t1 := &T{
+		common: common{
+			signal: make(chan bool),
+			w:      &buf,
+		},
+		context: ctx,
+	}
+	t1.Run("Test", parallelTestHelper)
+
+	lines := strings.Split(strings.TrimSpace(buf.String()), "\n")
+	if len(lines) != 6 {
+		t.Fatalf("parallelTestHelper gave %d lines of output; want 6", len(lines))
+	}
+	want := "helperfuncs_test.go:21: parallel"
+	if got := strings.TrimSpace(lines[1]); got != want {
+		t.Errorf("got output line %q; want %q", got, want)
+	}
+}
diff --git a/libgo/go/testing/helperfuncs_test.go b/libgo/go/testing/helperfuncs_test.go
new file mode 100644
index 0000000..7cb2e2c
--- /dev/null
+++ b/libgo/go/testing/helperfuncs_test.go
@@ -0,0 +1,67 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package testing
+
+import "sync"
+
+// The line numbering of this file is important for TestTBHelper.
+
+func notHelper(t *T, msg string) {
+	t.Error(msg)
+}
+
+func helper(t *T, msg string) {
+	t.Helper()
+	t.Error(msg)
+}
+
+func notHelperCallingHelper(t *T, msg string) {
+	helper(t, msg)
+}
+
+func helperCallingHelper(t *T, msg string) {
+	t.Helper()
+	helper(t, msg)
+}
+
+func testHelper(t *T) {
+	// Check combinations of directly and indirectly
+	// calling helper functions.
+	notHelper(t, "0")
+	helper(t, "1")
+	notHelperCallingHelper(t, "2")
+	helperCallingHelper(t, "3")
+
+	// Check a function literal closing over t that uses Helper.
+	fn := func(msg string) {
+		t.Helper()
+		t.Error(msg)
+	}
+	fn("4")
+
+	// Check that calling Helper from inside this test entry function
+	// doesn't have an effect.
+	t.Helper()
+	t.Error("5")
+
+	t.Run("sub", func(t *T) {
+		helper(t, "6")
+		notHelperCallingHelper(t, "7")
+		t.Helper()
+		t.Error("8")
+	})
+}
+
+func parallelTestHelper(t *T) {
+	var wg sync.WaitGroup
+	for i := 0; i < 5; i++ {
+		wg.Add(1)
+		go func() {
+			notHelperCallingHelper(t, "parallel")
+			wg.Done()
+		}()
+	}
+	wg.Wait()
+}
diff --git a/libgo/go/testing/internal/testdeps/deps.go b/libgo/go/testing/internal/testdeps/deps.go
index b08300b..042f696 100644
--- a/libgo/go/testing/internal/testdeps/deps.go
+++ b/libgo/go/testing/internal/testdeps/deps.go
@@ -49,3 +49,10 @@
 func (TestDeps) WriteProfileTo(name string, w io.Writer, debug int) error {
 	return pprof.Lookup(name).WriteTo(w, debug)
 }
+
+// ImportPath is the import path of the testing binary, set by the generated main function.
+var ImportPath string
+
+func (TestDeps) ImportPath() string {
+	return ImportPath
+}
diff --git a/libgo/go/testing/match.go b/libgo/go/testing/match.go
index 7751035..89e30d0 100644
--- a/libgo/go/testing/match.go
+++ b/libgo/go/testing/match.go
@@ -47,7 +47,7 @@
 	}
 }
 
-func (m *matcher) fullName(c *common, subname string) (name string, ok bool) {
+func (m *matcher) fullName(c *common, subname string) (name string, ok, partial bool) {
 	name = subname
 
 	m.mu.Lock()
@@ -62,15 +62,16 @@
 
 	// We check the full array of paths each time to allow for the case that
 	// a pattern contains a '/'.
-	for i, s := range strings.Split(name, "/") {
+	elem := strings.Split(name, "/")
+	for i, s := range elem {
 		if i >= len(m.filter) {
 			break
 		}
 		if ok, _ := m.matchFunc(m.filter[i], s); !ok {
-			return name, false
+			return name, false, false
 		}
 	}
-	return name, true
+	return name, true, len(elem) < len(m.filter)
 }
 
 func splitRegexp(s string) []string {
diff --git a/libgo/go/testing/match_test.go b/libgo/go/testing/match_test.go
index 8c1c5f4..8c09dc6 100644
--- a/libgo/go/testing/match_test.go
+++ b/libgo/go/testing/match_test.go
@@ -88,43 +88,44 @@
 		pattern     string
 		parent, sub string
 		ok          bool
+		partial     bool
 	}{
 		// Behavior without subtests.
-		{"", "", "TestFoo", true},
-		{"TestFoo", "", "TestFoo", true},
-		{"TestFoo/", "", "TestFoo", true},
-		{"TestFoo/bar/baz", "", "TestFoo", true},
-		{"TestFoo", "", "TestBar", false},
-		{"TestFoo/", "", "TestBar", false},
-		{"TestFoo/bar/baz", "", "TestBar/bar/baz", false},
+		{"", "", "TestFoo", true, false},
+		{"TestFoo", "", "TestFoo", true, false},
+		{"TestFoo/", "", "TestFoo", true, true},
+		{"TestFoo/bar/baz", "", "TestFoo", true, true},
+		{"TestFoo", "", "TestBar", false, false},
+		{"TestFoo/", "", "TestBar", false, false},
+		{"TestFoo/bar/baz", "", "TestBar/bar/baz", false, false},
 
 		// with subtests
-		{"", "TestFoo", "x", true},
-		{"TestFoo", "TestFoo", "x", true},
-		{"TestFoo/", "TestFoo", "x", true},
-		{"TestFoo/bar/baz", "TestFoo", "bar", true},
+		{"", "TestFoo", "x", true, false},
+		{"TestFoo", "TestFoo", "x", true, false},
+		{"TestFoo/", "TestFoo", "x", true, false},
+		{"TestFoo/bar/baz", "TestFoo", "bar", true, true},
 		// Subtest with a '/' in its name still allows for copy and pasted names
 		// to match.
-		{"TestFoo/bar/baz", "TestFoo", "bar/baz", true},
-		{"TestFoo/bar/baz", "TestFoo/bar", "baz", true},
-		{"TestFoo/bar/baz", "TestFoo", "x", false},
-		{"TestFoo", "TestBar", "x", false},
-		{"TestFoo/", "TestBar", "x", false},
-		{"TestFoo/bar/baz", "TestBar", "x/bar/baz", false},
+		{"TestFoo/bar/baz", "TestFoo", "bar/baz", true, false},
+		{"TestFoo/bar/baz", "TestFoo/bar", "baz", true, false},
+		{"TestFoo/bar/baz", "TestFoo", "x", false, false},
+		{"TestFoo", "TestBar", "x", false, false},
+		{"TestFoo/", "TestBar", "x", false, false},
+		{"TestFoo/bar/baz", "TestBar", "x/bar/baz", false, false},
 
 		// subtests only
-		{"", "TestFoo", "x", true},
-		{"/", "TestFoo", "x", true},
-		{"./", "TestFoo", "x", true},
-		{"./.", "TestFoo", "x", true},
-		{"/bar/baz", "TestFoo", "bar", true},
-		{"/bar/baz", "TestFoo", "bar/baz", true},
-		{"//baz", "TestFoo", "bar/baz", true},
-		{"//", "TestFoo", "bar/baz", true},
-		{"/bar/baz", "TestFoo/bar", "baz", true},
-		{"//foo", "TestFoo", "bar/baz", false},
-		{"/bar/baz", "TestFoo", "x", false},
-		{"/bar/baz", "TestBar", "x/bar/baz", false},
+		{"", "TestFoo", "x", true, false},
+		{"/", "TestFoo", "x", true, false},
+		{"./", "TestFoo", "x", true, false},
+		{"./.", "TestFoo", "x", true, false},
+		{"/bar/baz", "TestFoo", "bar", true, true},
+		{"/bar/baz", "TestFoo", "bar/baz", true, false},
+		{"//baz", "TestFoo", "bar/baz", true, false},
+		{"//", "TestFoo", "bar/baz", true, false},
+		{"/bar/baz", "TestFoo/bar", "baz", true, false},
+		{"//foo", "TestFoo", "bar/baz", false, false},
+		{"/bar/baz", "TestFoo", "x", false, false},
+		{"/bar/baz", "TestBar", "x/bar/baz", false, false},
 	}
 
 	for _, tc := range testCases {
@@ -134,9 +135,9 @@
 		if tc.parent != "" {
 			parent.level = 1
 		}
-		if n, ok := m.fullName(parent, tc.sub); ok != tc.ok {
-			t.Errorf("for pattern %q, fullName(parent=%q, sub=%q) = %q, ok %v; want ok %v",
-				tc.pattern, tc.parent, tc.sub, n, ok, tc.ok)
+		if n, ok, partial := m.fullName(parent, tc.sub); ok != tc.ok || partial != tc.partial {
+			t.Errorf("for pattern %q, fullName(parent=%q, sub=%q) = %q, ok %v partial %v; want ok %v partial %v",
+				tc.pattern, tc.parent, tc.sub, n, ok, partial, tc.ok, tc.partial)
 		}
 	}
 }
@@ -178,7 +179,7 @@
 	}
 
 	for i, tc := range testCases {
-		if got, _ := m.fullName(parent, tc.name); got != tc.want {
+		if got, _, _ := m.fullName(parent, tc.name); got != tc.want {
 			t.Errorf("%d:%s: got %q; want %q", i, tc.name, got, tc.want)
 		}
 	}
diff --git a/libgo/go/testing/quick/quick.go b/libgo/go/testing/quick/quick.go
index 95860fd..0457fc7 100644
--- a/libgo/go/testing/quick/quick.go
+++ b/libgo/go/testing/quick/quick.go
@@ -14,6 +14,7 @@
 	"math/rand"
 	"reflect"
 	"strings"
+	"time"
 )
 
 var defaultMaxCount *int = flag.Int("quickchecks", 100, "The default number of iterations for each check")
@@ -43,8 +44,10 @@
 	return f
 }
 
-// randInt64 returns a random integer taking half the range of an int64.
-func randInt64(rand *rand.Rand) int64 { return rand.Int63() - 1<<62 }
+// randInt64 returns a random int64.
+func randInt64(rand *rand.Rand) int64 {
+	return int64(rand.Uint64())
+}
 
 // complexSize is the maximum length of arbitrary values that contain other
 // values.
@@ -172,19 +175,20 @@
 
 // A Config structure contains options for running a test.
 type Config struct {
-	// MaxCount sets the maximum number of iterations. If zero,
-	// MaxCountScale is used.
+	// MaxCount sets the maximum number of iterations.
+	// If zero, MaxCountScale is used.
 	MaxCount int
-	// MaxCountScale is a non-negative scale factor applied to the default
-	// maximum. If zero, the default is unchanged.
+	// MaxCountScale is a non-negative scale factor applied to the
+	// default maximum.
+	// If zero, the default is unchanged.
 	MaxCountScale float64
-	// If non-nil, rand is a source of random numbers. Otherwise a default
-	// pseudo-random source will be used.
+	// Rand specifies a source of random numbers.
+	// If nil, a default pseudo-random source will be used.
 	Rand *rand.Rand
-	// If non-nil, the Values function generates a slice of arbitrary
-	// reflect.Values that are congruent with the arguments to the function
-	// being tested. Otherwise, the top-level Value function is used
-	// to generate them.
+	// Values specifies a function to generate a slice of
+	// arbitrary reflect.Values that are congruent with the
+	// arguments to the function being tested.
+	// If nil, the top-level Value function is used to generate them.
 	Values func([]reflect.Value, *rand.Rand)
 }
 
@@ -193,7 +197,7 @@
 // getRand returns the *rand.Rand to use for a given Config.
 func (c *Config) getRand() *rand.Rand {
 	if c.Rand == nil {
-		return rand.New(rand.NewSource(0))
+		return rand.New(rand.NewSource(time.Now().UnixNano()))
 	}
 	return c.Rand
 }
diff --git a/libgo/go/testing/quick/quick_test.go b/libgo/go/testing/quick/quick_test.go
index fe44359..4246cd1 100644
--- a/libgo/go/testing/quick/quick_test.go
+++ b/libgo/go/testing/quick/quick_test.go
@@ -307,3 +307,21 @@
 		t.Fatal(err)
 	}
 }
+
+func TestInt64(t *testing.T) {
+	var lo, hi int64
+	f := func(x int64) bool {
+		if x < lo {
+			lo = x
+		}
+		if x > hi {
+			hi = x
+		}
+		return true
+	}
+	cfg := &Config{MaxCount: 100000}
+	Check(f, cfg)
+	if uint64(lo)>>62 == 0 || uint64(hi)>>62 == 0 {
+		t.Errorf("int64 returned range %#016x,%#016x; does not look like full range", lo, hi)
+	}
+}
diff --git a/libgo/go/testing/sub_test.go b/libgo/go/testing/sub_test.go
index bb7b3e0..acf5dea 100644
--- a/libgo/go/testing/sub_test.go
+++ b/libgo/go/testing/sub_test.go
@@ -8,11 +8,18 @@
 	"bytes"
 	"fmt"
 	"regexp"
+	"runtime"
 	"strings"
+	"sync"
 	"sync/atomic"
 	"time"
 )
 
+func init() {
+	// Make benchmark tests run 10* faster.
+	*benchTime = 100 * time.Millisecond
+}
+
 func TestTestContext(t *T) {
 	const (
 		add1 = 0
@@ -455,8 +462,14 @@
 					_ = append([]byte(nil), buf[:]...)
 				}
 			}
-			b.Run("", func(b *B) { alloc(b) })
-			b.Run("", func(b *B) { alloc(b) })
+			b.Run("", func(b *B) {
+				alloc(b)
+				b.ReportAllocs()
+			})
+			b.Run("", func(b *B) {
+				alloc(b)
+				b.ReportAllocs()
+			})
 			// runtime.MemStats sometimes reports more allocations than the
 			// benchmark is responsible for. Luckily the point of this test is
 			// to ensure that the results are not underreported, so we can
@@ -517,6 +530,26 @@
 	Benchmark(func(b *B) {})
 }
 
+func TestBenchmarkStartsFrom1(t *T) {
+	var first = true
+	Benchmark(func(b *B) {
+		if first && b.N != 1 {
+			panic(fmt.Sprintf("Benchmark() first N=%v; want 1", b.N))
+		}
+		first = false
+	})
+}
+
+func TestBenchmarkReadMemStatsBeforeFirstRun(t *T) {
+	var first = true
+	Benchmark(func(b *B) {
+		if first && (b.startAllocs == 0 || b.startBytes == 0) {
+			panic(fmt.Sprintf("ReadMemStats not called before first run"))
+		}
+		first = false
+	})
+}
+
 func TestParallelSub(t *T) {
 	c := make(chan int)
 	block := make(chan int)
@@ -532,3 +565,59 @@
 		<-c
 	}
 }
+
+type funcWriter func([]byte) (int, error)
+
+func (fw funcWriter) Write(b []byte) (int, error) { return fw(b) }
+
+func TestRacyOutput(t *T) {
+	var runs int32  // The number of running Writes
+	var races int32 // Incremented for each race detected
+	raceDetector := func(b []byte) (int, error) {
+		// Check if some other goroutine is concurrently calling Write.
+		if atomic.LoadInt32(&runs) > 0 {
+			atomic.AddInt32(&races, 1) // Race detected!
+		}
+		atomic.AddInt32(&runs, 1)
+		defer atomic.AddInt32(&runs, -1)
+		runtime.Gosched() // Increase probability of a race
+		return len(b), nil
+	}
+
+	var wg sync.WaitGroup
+	root := &T{
+		common:  common{w: funcWriter(raceDetector), chatty: true},
+		context: newTestContext(1, newMatcher(regexp.MatchString, "", "")),
+	}
+	root.Run("", func(t *T) {
+		for i := 0; i < 100; i++ {
+			wg.Add(1)
+			go func(i int) {
+				defer wg.Done()
+				t.Run(fmt.Sprint(i), func(t *T) {
+					t.Logf("testing run %d", i)
+				})
+			}(i)
+		}
+	})
+	wg.Wait()
+
+	if races > 0 {
+		t.Errorf("detected %d racy Writes", races)
+	}
+}
+
+func TestBenchmark(t *T) {
+	res := Benchmark(func(b *B) {
+		for i := 0; i < 5; i++ {
+			b.Run("", func(b *B) {
+				for i := 0; i < b.N; i++ {
+					time.Sleep(time.Millisecond)
+				}
+			})
+		}
+	})
+	if res.NsPerOp() < 4000000 {
+		t.Errorf("want >5ms; got %v", time.Duration(res.NsPerOp()))
+	}
+}
diff --git a/libgo/go/testing/testing.go b/libgo/go/testing/testing.go
index b002aa0..a629742 100644
--- a/libgo/go/testing/testing.go
+++ b/libgo/go/testing/testing.go
@@ -83,16 +83,30 @@
 // ignores leading and trailing space.) These are examples of an example:
 //
 //     func ExampleHello() {
-//             fmt.Println("hello")
-//             // Output: hello
+//         fmt.Println("hello")
+//         // Output: hello
 //     }
 //
 //     func ExampleSalutations() {
-//             fmt.Println("hello, and")
-//             fmt.Println("goodbye")
-//             // Output:
-//             // hello, and
-//             // goodbye
+//         fmt.Println("hello, and")
+//         fmt.Println("goodbye")
+//         // Output:
+//         // hello, and
+//         // goodbye
+//     }
+//
+// The comment prefix "Unordered output:" is like "Output:", but matches any
+// line order:
+//
+//     func ExamplePerm() {
+//         for _, value := range Perm(4) {
+//             fmt.Println(value)
+//         }
+//         // Unordered output: 4
+//         // 2
+//         // 1
+//         // 3
+//         // 0
 //     }
 //
 // Example functions without output comments are compiled but not executed.
@@ -238,6 +252,7 @@
 	chatty               = flag.Bool("test.v", false, "verbose: print additional output")
 	count                = flag.Uint("test.count", 1, "run tests and benchmarks `n` times")
 	coverProfile         = flag.String("test.coverprofile", "", "write a coverage profile to `file`")
+	matchList            = flag.String("test.list", "", "list tests, examples, and benchmarch maching `regexp` then exit")
 	match                = flag.String("test.run", "", "run only tests and examples matching `regexp`")
 	memProfile           = flag.String("test.memprofile", "", "write a memory profile to `file`")
 	memProfileRate       = flag.Int("test.memprofilerate", 0, "set memory profiling `rate` (see runtime.MemProfileRate)")
@@ -247,7 +262,7 @@
 	mutexProfile         = flag.String("test.mutexprofile", "", "write a mutex contention profile to the named file after execution")
 	mutexProfileFraction = flag.Int("test.mutexprofilefraction", 1, "if >= 0, calls runtime.SetMutexProfileFraction()")
 	traceFile            = flag.String("test.trace", "", "write an execution trace to `file`")
-	timeout              = flag.Duration("test.timeout", 0, "fail test binary execution after duration `d` (0 means unlimited)")
+	timeout              = flag.Duration("test.timeout", 0, "panic test binary after duration `d` (0 means unlimited)")
 	cpuListStr           = flag.String("test.cpu", "", "comma-separated `list` of cpu counts to run each test with")
 	parallel             = flag.Int("test.parallel", runtime.GOMAXPROCS(0), "run at most `n` tests in parallel")
 
@@ -259,17 +274,20 @@
 // common holds the elements common between T and B and
 // captures common methods such as Errorf.
 type common struct {
-	mu         sync.RWMutex // guards output, failed, and done.
-	output     []byte       // Output generated by test or benchmark.
-	w          io.Writer    // For flushToParent.
-	chatty     bool         // A copy of the chatty flag.
-	ran        bool         // Test or benchmark (or one of its subtests) was executed.
-	failed     bool         // Test or benchmark has failed.
-	skipped    bool         // Test of benchmark has been skipped.
-	finished   bool         // Test function has completed.
-	done       bool         // Test is finished and all subtests have completed.
-	hasSub     int32        // written atomically
-	raceErrors int          // number of races detected during test
+	mu      sync.RWMutex        // guards this group of fields
+	output  []byte              // Output generated by test or benchmark.
+	w       io.Writer           // For flushToParent.
+	ran     bool                // Test or benchmark (or one of its subtests) was executed.
+	failed  bool                // Test or benchmark has failed.
+	skipped bool                // Test of benchmark has been skipped.
+	done    bool                // Test is finished and all subtests have completed.
+	helpers map[string]struct{} // functions to be skipped when writing file/line info
+
+	chatty     bool   // A copy of the chatty flag.
+	finished   bool   // Test function has completed.
+	hasSub     int32  // written atomically
+	raceErrors int    // number of races detected during test
+	runner     string // function name of tRunner running the test
 
 	parent   *common
 	level    int       // Nesting depth of test or benchmark.
@@ -298,10 +316,48 @@
 	return *chatty
 }
 
+// frameSkip searches, starting after skip frames, for the first caller frame
+// in a function not marked as a helper and returns the frames to skip
+// to reach that site. The search stops if it finds a tRunner function that
+// was the entry point into the test.
+// This function must be called with c.mu held.
+func (c *common) frameSkip(skip int) int {
+	if c.helpers == nil {
+		return skip
+	}
+	var pc [50]uintptr
+	// Skip two extra frames to account for this function
+	// and runtime.Callers itself.
+	n := runtime.Callers(skip+2, pc[:])
+	if n == 0 {
+		panic("testing: zero callers found")
+	}
+	frames := runtime.CallersFrames(pc[:n])
+	var frame runtime.Frame
+	more := true
+	for i := 0; more; i++ {
+		frame, more = frames.Next()
+		if frame.Function == c.runner {
+			// We've gone up all the way to the tRunner calling
+			// the test function (so the user must have
+			// called tb.Helper from inside that test function).
+			// Only skip up to the test function itself.
+			return skip + i - 1
+		}
+		if _, ok := c.helpers[frame.Function]; !ok {
+			// Found a frame that wasn't inside a helper function.
+			return skip + i
+		}
+	}
+	return skip
+}
+
 // decorate prefixes the string with the file and line of the call site
 // and inserts the final newline if needed and indentation tabs for formatting.
-func decorate(s string) string {
-	_, file, line, ok := runtime.Caller(3) // decorate + log + public function.
+// This function must be called with c.mu held.
+func (c *common) decorate(s string) string {
+	skip := c.frameSkip(3) // decorate + log + public function.
+	_, file, line, ok := runtime.Caller(skip)
 	if ok {
 		// Truncate file name at last file name separator.
 		if index := strings.LastIndex(file, "/"); index >= 0 {
@@ -391,6 +447,7 @@
 	SkipNow()
 	Skipf(format string, args ...interface{})
 	Skipped() bool
+	Helper()
 
 	// A private method to prevent users implementing the
 	// interface and so future additions to it will not
@@ -450,8 +507,9 @@
 // Failed reports whether the function has failed.
 func (c *common) Failed() bool {
 	c.mu.RLock()
-	defer c.mu.RUnlock()
-	return c.failed
+	failed := c.failed
+	c.mu.RUnlock()
+	return failed || c.raceErrors+race.Errors() > 0
 }
 
 // FailNow marks the function as having failed and stops its execution.
@@ -490,7 +548,7 @@
 func (c *common) log(s string) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	c.output = append(c.output, decorate(s)...)
+	c.output = append(c.output, c.decorate(s)...)
 }
 
 // Log formats its arguments using default formatting, analogous to Println,
@@ -568,8 +626,38 @@
 	return c.skipped
 }
 
+// Helper marks the calling function as a test helper function.
+// When printing file and line information, that function will be skipped.
+// Helper may be called simultaneously from multiple goroutines.
+// Helper has no effect if it is called directly from a TestXxx/BenchmarkXxx
+// function or a subtest/sub-benchmark function.
+func (c *common) Helper() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.helpers == nil {
+		c.helpers = make(map[string]struct{})
+	}
+	c.helpers[callerName(1)] = struct{}{}
+}
+
+// callerName gives the function name (qualified with a package path)
+// for the caller after skip frames (where 0 means the current function).
+func callerName(skip int) string {
+	// Make room for the skip PC.
+	var pc [2]uintptr
+	n := runtime.Callers(skip+2, pc[:]) // skip + runtime.Callers + callerName
+	if n == 0 {
+		panic("testing: zero callers found")
+	}
+	frames := runtime.CallersFrames(pc[:n])
+	frame, _ := frames.Next()
+	return frame.Function
+}
+
 // Parallel signals that this test is to be run in parallel with (and only with)
-// other parallel tests.
+// other parallel tests. When a test is run multiple times due to use of
+// -test.count or -test.cpu, multiple instances of a single test never run in
+// parallel with each other.
 func (t *T) Parallel() {
 	if t.isParallel {
 		panic("testing: t.Parallel called multiple times")
@@ -600,13 +688,14 @@
 }
 
 func tRunner(t *T, fn func(t *T)) {
+	t.runner = callerName(0)
+
 	// When this goroutine is done, either because fn(t)
 	// returned normally or because a test failure triggered
 	// a call to runtime.Goexit, record the duration and send
 	// a signal saying that the test is done.
 	defer func() {
-		t.raceErrors += race.Errors()
-		if t.raceErrors > 0 {
+		if t.raceErrors+race.Errors() > 0 {
 			t.Errorf("race detected during execution of test")
 		}
 
@@ -658,14 +747,15 @@
 	t.finished = true
 }
 
-// Run runs f as a subtest of t called name. It reports whether f succeeded.
-// Run will block until all its parallel subtests have completed.
+// Run runs f as a subtest of t called name. It reports whether f succeeded. Run
+// runs f in a separate goroutine and will block until all its parallel subtests
+// have completed.
 //
-// Run may be called simultaneously from multiple goroutines, but all such
-// calls must happen before the outer test function for t returns.
+// Run may be called simultaneously from multiple goroutines, but all such calls
+// must return before the outer test function for t returns.
 func (t *T) Run(name string, f func(t *T)) bool {
 	atomic.StoreInt32(&t.hasSub, 1)
-	testName, ok := t.context.match.fullName(&t.common, name)
+	testName, ok, _ := t.context.match.fullName(&t.common, name)
 	if !ok {
 		return true
 	}
@@ -687,7 +777,9 @@
 		root := t.parent
 		for ; root.parent != nil; root = root.parent {
 		}
+		root.mu.Lock()
 		fmt.Fprintf(root.w, "=== RUN   %s\n", t.name)
+		root.mu.Unlock()
 	}
 	// Instead of reducing the running count of this test before calling the
 	// tRunner and increasing it afterwards, we rely on tRunner keeping the
@@ -764,6 +856,7 @@
 func (f matchStringOnly) StopCPUProfile()                             {}
 func (f matchStringOnly) WriteHeapProfile(w io.Writer) error          { return errMain }
 func (f matchStringOnly) WriteProfileTo(string, io.Writer, int) error { return errMain }
+func (f matchStringOnly) ImportPath() string                          { return "" }
 
 // Main is an internal function, part of the implementation of the "go test" command.
 // It was exported because it is cross-package and predates "internal" packages.
@@ -793,6 +886,7 @@
 	StopCPUProfile()
 	WriteHeapProfile(io.Writer) error
 	WriteProfileTo(string, io.Writer, int) error
+	ImportPath() string
 }
 
 // MainStart is meant for use by tests generated by 'go test'.
@@ -814,6 +908,11 @@
 		flag.Parse()
 	}
 
+	if len(*matchList) != 0 {
+		listTests(m.deps.MatchString, m.tests, m.benchmarks, m.examples)
+		return 0
+	}
+
 	parseCpuList()
 
 	m.before()
@@ -825,7 +924,7 @@
 	if !testRan && !exampleRan && *matchBenchmarks == "" {
 		fmt.Fprintln(os.Stderr, "testing: warning: no tests to run")
 	}
-	if !testOk || !exampleOk || !runBenchmarks(m.deps.MatchString, m.benchmarks) || race.Errors() > 0 {
+	if !testOk || !exampleOk || !runBenchmarks(m.deps.ImportPath(), m.deps.MatchString, m.benchmarks) || race.Errors() > 0 {
 		fmt.Println("FAIL")
 		m.after()
 		return 1
@@ -853,6 +952,29 @@
 	}
 }
 
+func listTests(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample) {
+	if _, err := matchString(*matchList, "non-empty"); err != nil {
+		fmt.Fprintf(os.Stderr, "testing: invalid regexp in -test.list (%q): %s\n", *matchList, err)
+		os.Exit(1)
+	}
+
+	for _, test := range tests {
+		if ok, _ := matchString(*matchList, test.Name); ok {
+			fmt.Println(test.Name)
+		}
+	}
+	for _, bench := range benchmarks {
+		if ok, _ := matchString(*matchList, bench.Name); ok {
+			fmt.Println(bench.Name)
+		}
+	}
+	for _, example := range examples {
+		if ok, _ := matchString(*matchList, example.Name); ok {
+			fmt.Println(example.Name)
+		}
+	}
+}
+
 // An internal function but exported because it is cross-package; part of the implementation
 // of the "go test" command.
 func RunTests(matchString func(pat, str string) (bool, error), tests []InternalTest) (ok bool) {
diff --git a/libgo/go/text/scanner/example_test.go b/libgo/go/text/scanner/example_test.go
index f48c31d..9e2d5b7 100644
--- a/libgo/go/text/scanner/example_test.go
+++ b/libgo/go/text/scanner/example_test.go
@@ -14,28 +14,25 @@
 
 func Example() {
 	const src = `
-	// This is scanned code.
-	if a > 10 {
-		someParsable = text
-	}`
+// This is scanned code.
+if a > 10 {
+	someParsable = text
+}`
 	var s scanner.Scanner
-	s.Filename = "example"
 	s.Init(strings.NewReader(src))
-	var tok rune
-	for tok != scanner.EOF {
-		tok = s.Scan()
-		fmt.Println("At position", s.Pos(), ":", s.TokenText())
+	s.Filename = "example"
+	for tok := s.Scan(); tok != scanner.EOF; tok = s.Scan() {
+		fmt.Printf("%s: %s\n", s.Position, s.TokenText())
 	}
 
 	// Output:
-	// At position example:3:4 : if
-	// At position example:3:6 : a
-	// At position example:3:8 : >
-	// At position example:3:11 : 10
-	// At position example:3:13 : {
-	// At position example:4:15 : someParsable
-	// At position example:4:17 : =
-	// At position example:4:22 : text
-	// At position example:5:3 : }
-	// At position example:5:3 :
+	// example:3:1: if
+	// example:3:4: a
+	// example:3:6: >
+	// example:3:8: 10
+	// example:3:11: {
+	// example:4:2: someParsable
+	// example:4:15: =
+	// example:4:17: text
+	// example:5:1: }
 }
diff --git a/libgo/go/text/scanner/scanner.go b/libgo/go/text/scanner/scanner.go
index e085f8a..6fb0422 100644
--- a/libgo/go/text/scanner/scanner.go
+++ b/libgo/go/text/scanner/scanner.go
@@ -166,7 +166,8 @@
 	// The Filename field is always left untouched by the Scanner.
 	// If an error is reported (via Error) and Position is invalid,
 	// the scanner is not inside a token. Call Pos to obtain an error
-	// position in that case.
+	// position in that case, or to obtain the position immediately
+	// after the most recently scanned token.
 	Position
 }
 
@@ -637,6 +638,8 @@
 
 // Pos returns the position of the character immediately after
 // the character or token returned by the last call to Next or Scan.
+// Use the Scanner's Position field for the start position of the most
+// recently scanned token.
 func (s *Scanner) Pos() (pos Position) {
 	pos.Filename = s.Filename
 	pos.Offset = s.srcBufOffset + s.srcPos - s.lastCharLen
diff --git a/libgo/go/text/template/doc.go b/libgo/go/text/template/doc.go
index fe59e3f..d174ebd 100644
--- a/libgo/go/text/template/doc.go
+++ b/libgo/go/text/template/doc.go
@@ -20,7 +20,8 @@
 "{{" and "}}"; all text outside actions is copied to the output unchanged.
 Except for raw strings, actions may not span newlines, although comments can.
 
-Once parsed, a template may be executed safely in parallel.
+Once parsed, a template may be executed safely in parallel, although if parallel
+executions share a Writer the output may be interleaved.
 
 Here is a trivial example that prints "17 items are made of wool".
 
@@ -80,14 +81,14 @@
 
 	{{if pipeline}} T1 {{end}}
 		If the value of the pipeline is empty, no output is generated;
-		otherwise, T1 is executed.  The empty values are false, 0, any
+		otherwise, T1 is executed. The empty values are false, 0, any
 		nil pointer or interface value, and any array, slice, map, or
 		string of length zero.
 		Dot is unaffected.
 
 	{{if pipeline}} T1 {{else}} T0 {{end}}
 		If the value of the pipeline is empty, T0 is executed;
-		otherwise, T1 is executed.  Dot is unaffected.
+		otherwise, T1 is executed. Dot is unaffected.
 
 	{{if pipeline}} T1 {{else if pipeline}} T0 {{end}}
 		To simplify the appearance of if-else chains, the else action
@@ -241,19 +242,19 @@
 variable produces no output.
 
 If a "range" action initializes a variable, the variable is set to the
-successive elements of the iteration.  Also, a "range" may declare two
+successive elements of the iteration. Also, a "range" may declare two
 variables, separated by a comma:
 
 	range $index, $element := pipeline
 
 in which case $index and $element are set to the successive values of the
-array/slice index or map key and element, respectively.  Note that if there is
+array/slice index or map key and element, respectively. Note that if there is
 only one variable, it is assigned the element; this is opposite to the
 convention in Go range clauses.
 
 A variable's scope extends to the "end" action of the control structure ("if",
 "with", or "range") in which it is declared, or to the end of the template if
-there is no such control structure.  A template invocation does not inherit
+there is no such control structure. A template invocation does not inherit
 variables from the point of its invocation.
 
 When execution begins, $ is set to the data argument passed to Execute, that is,
@@ -314,7 +315,8 @@
 		or the returned error value is non-nil, execution stops.
 	html
 		Returns the escaped HTML equivalent of the textual
-		representation of its arguments.
+		representation of its arguments. This function is unavailable
+		in html/template, with a few exceptions.
 	index
 		Returns the result of indexing its first argument by the
 		following arguments. Thus "index x 1 2 3" is, in Go syntax,
@@ -340,6 +342,8 @@
 	urlquery
 		Returns the escaped value of the textual representation of
 		its arguments in a form suitable for embedding in a URL query.
+		This function is unavailable in html/template, with a few
+		exceptions.
 
 The boolean functions take any zero value to be false and a non-zero
 value to be true.
diff --git a/libgo/go/text/template/exec.go b/libgo/go/text/template/exec.go
index 89d3e37..29eb68f 100644
--- a/libgo/go/text/template/exec.go
+++ b/libgo/go/text/template/exec.go
@@ -155,7 +155,8 @@
 // If an error occurs executing the template or writing its output,
 // execution stops, but partial results may already have been written to
 // the output writer.
-// A template may be executed safely in parallel.
+// A template may be executed safely in parallel, although if parallel
+// executions share a Writer the output may be interleaved.
 func (t *Template) ExecuteTemplate(wr io.Writer, name string, data interface{}) error {
 	var tmpl *Template
 	if t.common != nil {
@@ -172,7 +173,8 @@
 // If an error occurs executing the template or writing its output,
 // execution stops, but partial results may already have been written to
 // the output writer.
-// A template may be executed safely in parallel.
+// A template may be executed safely in parallel, although if parallel
+// executions share a Writer the output may be interleaved.
 //
 // If data is a reflect.Value, the template applies to the concrete
 // value that the reflect.Value holds, as in fmt.Print.
@@ -553,7 +555,7 @@
 	// Unless it's an interface, need to get to a value of type *T to guarantee
 	// we see all methods of T and *T.
 	ptr := receiver
-	if ptr.Kind() != reflect.Interface && ptr.CanAddr() {
+	if ptr.Kind() != reflect.Interface && ptr.Kind() != reflect.Ptr && ptr.CanAddr() {
 		ptr = ptr.Addr()
 	}
 	if method := ptr.MethodByName(fieldName); method.IsValid() {
@@ -630,7 +632,7 @@
 		if numIn < numFixed {
 			s.errorf("wrong number of args for %s: want at least %d got %d", name, typ.NumIn()-1, len(args))
 		}
-	} else if numIn < typ.NumIn()-1 || !typ.IsVariadic() && numIn != typ.NumIn() {
+	} else if numIn != typ.NumIn() {
 		s.errorf("wrong number of args for %s: want %d got %d", name, typ.NumIn(), len(args))
 	}
 	if !goodFunc(typ) {
diff --git a/libgo/go/text/template/exec_test.go b/libgo/go/text/template/exec_test.go
index 5892b27..9f7e637 100644
--- a/libgo/go/text/template/exec_test.go
+++ b/libgo/go/text/template/exec_test.go
@@ -147,6 +147,8 @@
 	Tmpl:                 Must(New("x").Parse("test template")), // "x" is the value of .X
 }
 
+var tSliceOfNil = []*T{nil}
+
 // A non-empty interface.
 type I interface {
 	Method0() string
@@ -337,6 +339,7 @@
 		"true", tVal, true},
 	{".NilOKFunc not nil", "{{call .NilOKFunc .PI}}", "false", tVal, true},
 	{".NilOKFunc nil", "{{call .NilOKFunc nil}}", "true", tVal, true},
+	{"method on nil value from slice", "-{{range .}}{{.Method1 1234}}{{end}}-", "-1234-", tSliceOfNil, true},
 
 	// Function call builtin.
 	{".BinaryFunc", "{{call .BinaryFunc `1` `2`}}", "[1=2]", tVal, true},
diff --git a/libgo/go/text/template/funcs.go b/libgo/go/text/template/funcs.go
index 3047b27..9107431 100644
--- a/libgo/go/text/template/funcs.go
+++ b/libgo/go/text/template/funcs.go
@@ -489,6 +489,7 @@
 	htmlAmp  = []byte("&amp;")
 	htmlLt   = []byte("&lt;")
 	htmlGt   = []byte("&gt;")
+	htmlNull = []byte("\uFFFD")
 )
 
 // HTMLEscape writes to w the escaped HTML equivalent of the plain text data b.
@@ -497,6 +498,8 @@
 	for i, c := range b {
 		var html []byte
 		switch c {
+		case '\000':
+			html = htmlNull
 		case '"':
 			html = htmlQuot
 		case '\'':
@@ -520,7 +523,7 @@
 // HTMLEscapeString returns the escaped HTML equivalent of the plain text data s.
 func HTMLEscapeString(s string) string {
 	// Avoid allocation if we can.
-	if !strings.ContainsAny(s, `'"&<>`) {
+	if !strings.ContainsAny(s, "'\"&<>\000") {
 		return s
 	}
 	var b bytes.Buffer
diff --git a/libgo/go/text/template/parse/lex_test.go b/libgo/go/text/template/parse/lex_test.go
index d655d78..2c73bb6 100644
--- a/libgo/go/text/template/parse/lex_test.go
+++ b/libgo/go/text/template/parse/lex_test.go
@@ -498,7 +498,7 @@
 	// We need to duplicate template.Parse here to hold on to the lexer.
 	const text = "erroneous{{define}}{{else}}1234"
 	lexer := lex("foo", text, "{{", "}}")
-	_, err := New("root").parseLexer(lexer, text)
+	_, err := New("root").parseLexer(lexer)
 	if err == nil {
 		t.Fatalf("expected error")
 	}
@@ -511,7 +511,7 @@
 
 // parseLexer is a local version of parse that lets us pass in the lexer instead of building it.
 // We expect an error, so the tree set and funcs list are explicitly nil.
-func (t *Tree) parseLexer(lex *lexer, text string) (tree *Tree, err error) {
+func (t *Tree) parseLexer(lex *lexer) (tree *Tree, err error) {
 	defer t.recover(&err)
 	t.ParseName = t.Name
 	t.startParse(nil, lex, map[string]*Tree{})
diff --git a/libgo/go/text/template/parse/parse.go b/libgo/go/text/template/parse/parse.go
index 6060c6d..a91a544 100644
--- a/libgo/go/text/template/parse/parse.go
+++ b/libgo/go/text/template/parse/parse.go
@@ -202,7 +202,6 @@
 		}
 		*errp = e.(error)
 	}
-	return
 }
 
 // startParse initializes the parser, using the lexer.
diff --git a/libgo/go/text/template/template.go b/libgo/go/text/template/template.go
index 3b4f34b..2246f67 100644
--- a/libgo/go/text/template/template.go
+++ b/libgo/go/text/template/template.go
@@ -159,6 +159,7 @@
 }
 
 // Funcs adds the elements of the argument map to the template's function map.
+// It must be called before the template is parsed.
 // It panics if a value in the map is not a function with appropriate return
 // type or if the name cannot be used syntactically as a function in a template.
 // It is legal to overwrite elements of the map. The return value is the template,
diff --git a/libgo/go/time/example_test.go b/libgo/go/time/example_test.go
index 7dc2bb5..aeb63ca 100644
--- a/libgo/go/time/example_test.go
+++ b/libgo/go/time/example_test.go
@@ -256,6 +256,9 @@
 	for _, d := range trunc {
 		fmt.Printf("t.Truncate(%5s) = %s\n", d, t.Truncate(d).Format("15:04:05.999999999"))
 	}
+	// To round to the last midnight in the local timezone, create a new Date.
+	midnight := time.Date(t.Year(), t.Month(), t.Day(), 0, 0, 0, 0, time.Local)
+	_ = midnight
 
 	// Output:
 	// t.Truncate(  1ns) = 12:15:30.918273645
diff --git a/libgo/go/time/export_test.go b/libgo/go/time/export_test.go
index 6cd535f..4c08ab1 100644
--- a/libgo/go/time/export_test.go
+++ b/libgo/go/time/export_test.go
@@ -18,7 +18,20 @@
 	localOnce.Do(initTestingZone)
 }
 
+func ZoneinfoForTesting() *string {
+	return zoneinfo
+}
+
+func ResetZoneinfoForTesting() {
+	zoneinfo = nil
+	zoneinfoOnce = sync.Once{}
+}
+
 var (
 	ForceZipFileForTesting = forceZipFileForTesting
 	ParseTimeZone          = parseTimeZone
+	SetMono                = (*Time).setMono
+	GetMono                = (*Time).mono
+	ErrLocation            = errLocation
+	ReadFile               = readFile
 )
diff --git a/libgo/go/time/format.go b/libgo/go/time/format.go
index b903e14..8c16e87 100644
--- a/libgo/go/time/format.go
+++ b/libgo/go/time/format.go
@@ -61,6 +61,8 @@
 // RFC822, RFC822Z, RFC1123, and RFC1123Z are useful for formatting;
 // when used with time.Parse they do not accept all the time formats
 // permitted by the RFCs.
+// The RFC3339Nano format removes trailing zeros from the seconds field
+// and thus may not sort correctly once formatted.
 const (
 	ANSIC       = "Mon Jan _2 15:04:05 2006"
 	UnixDate    = "Mon Jan _2 15:04:05 MST 2006"
@@ -424,8 +426,41 @@
 
 // String returns the time formatted using the format string
 //	"2006-01-02 15:04:05.999999999 -0700 MST"
+//
+// If the time has a monotonic clock reading, the returned string
+// includes a final field "m=±<value>", where value is the monotonic
+// clock reading formatted as a decimal number of seconds.
+//
+// The returned string is meant for debugging; for a stable serialized
+// representation, use t.MarshalText, t.MarshalBinary, or t.Format
+// with an explicit format string.
 func (t Time) String() string {
-	return t.Format("2006-01-02 15:04:05.999999999 -0700 MST")
+	s := t.Format("2006-01-02 15:04:05.999999999 -0700 MST")
+
+	// Format monotonic clock reading as m=±ddd.nnnnnnnnn.
+	if t.wall&hasMonotonic != 0 {
+		m2 := uint64(t.ext)
+		sign := byte('+')
+		if t.ext < 0 {
+			sign = '-'
+			m2 = -m2
+		}
+		m1, m2 := m2/1e9, m2%1e9
+		m0, m1 := m1/1e9, m1%1e9
+		var buf []byte
+		buf = append(buf, " m="...)
+		buf = append(buf, sign)
+		wid := 0
+		if m0 != 0 {
+			buf = appendInt(buf, int(m0), 0)
+			wid = 9
+		}
+		buf = appendInt(buf, int(m1), wid)
+		buf = append(buf, '.')
+		buf = appendInt(buf, int(m2), 9)
+		s += string(buf)
+	}
+	return s
 }
 
 // Format returns a textual representation of the time value formatted
@@ -725,11 +760,6 @@
 // location and zone in the returned time. Otherwise it records the time as
 // being in a fabricated location with time fixed at the given zone offset.
 //
-// No checking is done that the day of the month is within the month's
-// valid dates; any one- or two-digit value is accepted. For example
-// February 31 and even February 99 are valid dates, specifying dates
-// in March and May. This behavior is consistent with time.Date.
-//
 // When parsing a time with a zone abbreviation like MST, if the zone abbreviation
 // has a defined offset in the current location, then that offset is used.
 // The zone abbreviation "UTC" is recognized as UTC regardless of location.
@@ -1022,11 +1052,11 @@
 
 	if zoneOffset != -1 {
 		t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
-		t.sec -= int64(zoneOffset)
+		t.addSec(-int64(zoneOffset))
 
 		// Look for local zone with the given offset.
 		// If that zone was in effect at the given time, use it.
-		name, offset, _, _, _ := local.lookup(t.sec + internalToUnix)
+		name, offset, _, _, _ := local.lookup(t.unixSec())
 		if offset == zoneOffset && (zoneName == "" || name == zoneName) {
 			t.setLoc(local)
 			return t, nil
@@ -1041,9 +1071,9 @@
 		t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
 		// Look for local zone with the given offset.
 		// If that zone was in effect at the given time, use it.
-		offset, _, ok := local.lookupName(zoneName, t.sec+internalToUnix)
+		offset, _, ok := local.lookupName(zoneName, t.unixSec())
 		if ok {
-			t.sec -= int64(offset)
+			t.addSec(-int64(offset))
 			t.setLoc(local)
 			return t, nil
 		}
diff --git a/libgo/go/time/format_test.go b/libgo/go/time/format_test.go
index 0e4a417..abaeb50 100644
--- a/libgo/go/time/format_test.go
+++ b/libgo/go/time/format_test.go
@@ -380,8 +380,8 @@
 func TestFormatAndParse(t *testing.T) {
 	const fmt = "Mon MST " + RFC3339 // all fields
 	f := func(sec int64) bool {
-		t1 := Unix(sec, 0)
-		if t1.Year() < 1000 || t1.Year() > 9999 {
+		t1 := Unix(sec/2, 0)
+		if t1.Year() < 1000 || t1.Year() > 9999 || t1.Unix() != sec {
 			// not required to work
 			return true
 		}
diff --git a/libgo/go/time/genzabbrs.go b/libgo/go/time/genzabbrs.go
index 6281f73..824a67f 100644
--- a/libgo/go/time/genzabbrs.go
+++ b/libgo/go/time/genzabbrs.go
@@ -142,8 +142,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// generated by genzabbrs.go from
-// {{.URL}}
+// Code generated by genzabbrs.go; DO NOT EDIT.
+// Based on information from {{.URL}}
 
 package time
 
diff --git a/libgo/go/time/mono_test.go b/libgo/go/time/mono_test.go
new file mode 100644
index 0000000..8778ab7
--- /dev/null
+++ b/libgo/go/time/mono_test.go
@@ -0,0 +1,261 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package time_test
+
+import (
+	"strings"
+	"testing"
+	. "time"
+)
+
+func TestHasMonotonicClock(t *testing.T) {
+	yes := func(expr string, tt Time) {
+		if GetMono(&tt) == 0 {
+			t.Errorf("%s: missing monotonic clock reading", expr)
+		}
+	}
+	no := func(expr string, tt Time) {
+		if GetMono(&tt) != 0 {
+			t.Errorf("%s: unexpected monotonic clock reading", expr)
+		}
+	}
+
+	yes("<-After(1)", <-After(1))
+	ticker := NewTicker(1)
+	yes("<-Tick(1)", <-ticker.C)
+	ticker.Stop()
+	no("Date(2009, 11, 23, 0, 0, 0, 0, UTC)", Date(2009, 11, 23, 0, 0, 0, 0, UTC))
+	tp, _ := Parse(UnixDate, "Sat Mar  7 11:06:39 PST 2015")
+	no(`Parse(UnixDate, "Sat Mar  7 11:06:39 PST 2015")`, tp)
+	no("Unix(1486057371, 0)", Unix(1486057371, 0))
+
+	yes("Now()", Now())
+
+	tu := Unix(1486057371, 0)
+	tm := tu
+	SetMono(&tm, 123456)
+	no("tu", tu)
+	yes("tm", tm)
+
+	no("tu.Add(1)", tu.Add(1))
+	no("tu.In(UTC)", tu.In(UTC))
+	no("tu.AddDate(1, 1, 1)", tu.AddDate(1, 1, 1))
+	no("tu.AddDate(0, 0, 0)", tu.AddDate(0, 0, 0))
+	no("tu.Local()", tu.Local())
+	no("tu.UTC()", tu.UTC())
+	no("tu.Round(2)", tu.Round(2))
+	no("tu.Truncate(2)", tu.Truncate(2))
+
+	yes("tm.Add(1)", tm.Add(1))
+	no("tm.AddDate(1, 1, 1)", tm.AddDate(1, 1, 1))
+	no("tm.AddDate(0, 0, 0)", tm.AddDate(0, 0, 0))
+	no("tm.In(UTC)", tm.In(UTC))
+	no("tm.Local()", tm.Local())
+	no("tm.UTC()", tm.UTC())
+	no("tm.Round(2)", tm.Round(2))
+	no("tm.Truncate(2)", tm.Truncate(2))
+}
+
+func TestMonotonicAdd(t *testing.T) {
+	tm := Unix(1486057371, 123456)
+	SetMono(&tm, 123456789012345)
+
+	t2 := tm.Add(1e8)
+	if t2.Nanosecond() != 100123456 {
+		t.Errorf("t2.Nanosecond() = %d, want 100123456", t2.Nanosecond())
+	}
+	if GetMono(&t2) != 123456889012345 {
+		t.Errorf("t2.mono = %d, want 123456889012345", GetMono(&t2))
+	}
+
+	t3 := tm.Add(-9e18) // wall now out of range
+	if t3.Nanosecond() != 123456 {
+		t.Errorf("t3.Nanosecond() = %d, want 123456", t3.Nanosecond())
+	}
+	if GetMono(&t3) != 0 {
+		t.Errorf("t3.mono = %d, want 0 (wall time out of range for monotonic reading)", GetMono(&t3))
+	}
+
+	t4 := tm.Add(+9e18) // wall now out of range
+	if t4.Nanosecond() != 123456 {
+		t.Errorf("t4.Nanosecond() = %d, want 123456", t4.Nanosecond())
+	}
+	if GetMono(&t4) != 0 {
+		t.Errorf("t4.mono = %d, want 0 (wall time out of range for monotonic reading)", GetMono(&t4))
+	}
+
+	tn := Now()
+	tn1 := tn.Add(1 * Hour)
+	Sleep(100 * Millisecond)
+	d := Until(tn1)
+	if d < 59*Minute {
+		t.Errorf("Until(Now().Add(1*Hour)) = %v, wanted at least 59m", d)
+	}
+	now := Now()
+	if now.After(tn1) {
+		t.Errorf("Now().After(Now().Add(1*Hour)) = true, want false")
+	}
+	if !tn1.After(now) {
+		t.Errorf("Now().Add(1*Hour).After(now) = false, want true")
+	}
+	if tn1.Before(now) {
+		t.Errorf("Now().Add(1*Hour).Before(Now()) = true, want false")
+	}
+	if !now.Before(tn1) {
+		t.Errorf("Now().Before(Now().Add(1*Hour)) = false, want true")
+	}
+}
+
+func TestMonotonicSub(t *testing.T) {
+	t1 := Unix(1483228799, 995e6)
+	SetMono(&t1, 123456789012345)
+
+	t2 := Unix(1483228799, 5e6)
+	SetMono(&t2, 123456789012345+10e6)
+
+	t3 := Unix(1483228799, 995e6)
+	SetMono(&t3, 123456789012345+1e9)
+
+	t1w := t1.AddDate(0, 0, 0)
+	if GetMono(&t1w) != 0 {
+		t.Fatalf("AddDate didn't strip monotonic clock reading")
+	}
+	t2w := t2.AddDate(0, 0, 0)
+	if GetMono(&t2w) != 0 {
+		t.Fatalf("AddDate didn't strip monotonic clock reading")
+	}
+	t3w := t3.AddDate(0, 0, 0)
+	if GetMono(&t3w) != 0 {
+		t.Fatalf("AddDate didn't strip monotonic clock reading")
+	}
+
+	sub := func(txs, tys string, tx, txw, ty, tyw Time, d, dw Duration) {
+		check := func(expr string, d, want Duration) {
+			if d != want {
+				t.Errorf("%s = %v, want %v", expr, d, want)
+			}
+		}
+		check(txs+".Sub("+tys+")", tx.Sub(ty), d)
+		check(txs+"w.Sub("+tys+")", txw.Sub(ty), dw)
+		check(txs+".Sub("+tys+"w)", tx.Sub(tyw), dw)
+		check(txs+"w.Sub("+tys+"w)", txw.Sub(tyw), dw)
+	}
+	sub("t1", "t1", t1, t1w, t1, t1w, 0, 0)
+	sub("t1", "t2", t1, t1w, t2, t2w, -10*Millisecond, 990*Millisecond)
+	sub("t1", "t3", t1, t1w, t3, t3w, -1000*Millisecond, 0)
+
+	sub("t2", "t1", t2, t2w, t1, t1w, 10*Millisecond, -990*Millisecond)
+	sub("t2", "t2", t2, t2w, t2, t2w, 0, 0)
+	sub("t2", "t3", t2, t2w, t3, t3w, -990*Millisecond, -990*Millisecond)
+
+	sub("t3", "t1", t3, t3w, t1, t1w, 1000*Millisecond, 0)
+	sub("t3", "t2", t3, t3w, t2, t2w, 990*Millisecond, 990*Millisecond)
+	sub("t3", "t3", t3, t3w, t3, t3w, 0, 0)
+
+	cmp := func(txs, tys string, tx, txw, ty, tyw Time, c, cw int) {
+		check := func(expr string, b, want bool) {
+			if b != want {
+				t.Errorf("%s = %v, want %v", expr, b, want)
+			}
+		}
+		check(txs+".After("+tys+")", tx.After(ty), c > 0)
+		check(txs+"w.After("+tys+")", txw.After(ty), cw > 0)
+		check(txs+".After("+tys+"w)", tx.After(tyw), cw > 0)
+		check(txs+"w.After("+tys+"w)", txw.After(tyw), cw > 0)
+
+		check(txs+".Before("+tys+")", tx.Before(ty), c < 0)
+		check(txs+"w.Before("+tys+")", txw.Before(ty), cw < 0)
+		check(txs+".Before("+tys+"w)", tx.Before(tyw), cw < 0)
+		check(txs+"w.Before("+tys+"w)", txw.Before(tyw), cw < 0)
+
+		check(txs+".Equal("+tys+")", tx.Equal(ty), c == 0)
+		check(txs+"w.Equal("+tys+")", txw.Equal(ty), cw == 0)
+		check(txs+".Equal("+tys+"w)", tx.Equal(tyw), cw == 0)
+		check(txs+"w.Equal("+tys+"w)", txw.Equal(tyw), cw == 0)
+	}
+
+	cmp("t1", "t1", t1, t1w, t1, t1w, 0, 0)
+	cmp("t1", "t2", t1, t1w, t2, t2w, -1, +1)
+	cmp("t1", "t3", t1, t1w, t3, t3w, -1, 0)
+
+	cmp("t2", "t1", t2, t2w, t1, t1w, +1, -1)
+	cmp("t2", "t2", t2, t2w, t2, t2w, 0, 0)
+	cmp("t2", "t3", t2, t2w, t3, t3w, -1, -1)
+
+	cmp("t3", "t1", t3, t3w, t1, t1w, +1, 0)
+	cmp("t3", "t2", t3, t3w, t2, t2w, +1, +1)
+	cmp("t3", "t3", t3, t3w, t3, t3w, 0, 0)
+}
+
+func TestMonotonicOverflow(t *testing.T) {
+	t1 := Now().Add(-30 * Second)
+	d := Until(t1)
+	if d < -35*Second || -30*Second < d {
+		t.Errorf("Until(Now().Add(-30s)) = %v, want roughly -30s (-35s to -30s)", d)
+	}
+
+	t1 = Now().Add(30 * Second)
+	d = Until(t1)
+	if d < 25*Second || 30*Second < d {
+		t.Errorf("Until(Now().Add(-30s)) = %v, want roughly 30s (25s to 30s)", d)
+	}
+
+	t0 := Now()
+	t1 = t0.Add(Duration(1<<63 - 1))
+	if GetMono(&t1) != 0 {
+		t.Errorf("Now().Add(maxDuration) has monotonic clock reading (%v => %v %d %d)", t0.String(), t1.String(), t0.Unix(), t1.Unix())
+	}
+	t2 := t1.Add(-Duration(1<<63 - 1))
+	d = Since(t2)
+	if d < -10*Second || 10*Second < d {
+		t.Errorf("Since(Now().Add(max).Add(-max)) = %v, want [-10s, 10s]", d)
+	}
+
+	t0 = Now()
+	t1 = t0.Add(1 * Hour)
+	Sleep(100 * Millisecond)
+	t2 = Now().Add(-5 * Second)
+	if !t1.After(t2) {
+		t.Errorf("Now().Add(1*Hour).After(Now().Add(-5*Second)) = false, want true\nt1=%v\nt2=%v", t1, t2)
+	}
+	if t2.After(t1) {
+		t.Errorf("Now().Add(-5*Second).After(Now().Add(1*Hour)) = true, want false\nt1=%v\nt2=%v", t1, t2)
+	}
+	if t1.Before(t2) {
+		t.Errorf("Now().Add(1*Hour).Before(Now().Add(-5*Second)) = true, want false\nt1=%v\nt2=%v", t1, t2)
+	}
+	if !t2.Before(t1) {
+		t.Errorf("Now().Add(-5*Second).Before(Now().Add(1*Hour)) = false, want true\nt1=%v\nt2=%v", t1, t2)
+	}
+}
+
+var monotonicStringTests = []struct {
+	mono int64
+	want string
+}{
+	{0, "m=+0.000000000"},
+	{123456789, "m=+0.123456789"},
+	{-123456789, "m=-0.123456789"},
+	{123456789000, "m=+123.456789000"},
+	{-123456789000, "m=-123.456789000"},
+	{9e18, "m=+9000000000.000000000"},
+	{-9e18, "m=-9000000000.000000000"},
+	{-1 << 63, "m=-9223372036.854775808"},
+}
+
+func TestMonotonicString(t *testing.T) {
+	t1 := Now()
+	t.Logf("Now() = %v", t1)
+
+	for _, tt := range monotonicStringTests {
+		t1 := Now()
+		SetMono(&t1, tt.mono)
+		s := t1.String()
+		got := s[strings.LastIndex(s, " ")+1:]
+		if got != tt.want {
+			t.Errorf("with mono=%d: got %q; want %q", tt.mono, got, tt.want)
+		}
+	}
+}
diff --git a/libgo/go/time/sleep_test.go b/libgo/go/time/sleep_test.go
index c286bd0..546b28a 100644
--- a/libgo/go/time/sleep_test.go
+++ b/libgo/go/time/sleep_test.go
@@ -227,7 +227,7 @@
 	err := errors.New("!=nil")
 	for i := 0; i < attempts && err != nil; i++ {
 		delta := Duration(20+i*50) * Millisecond
-		if err = testAfterQueuing(t, delta); err != nil {
+		if err = testAfterQueuing(delta); err != nil {
 			t.Logf("attempt %v failed: %v", i, err)
 		}
 	}
@@ -248,7 +248,7 @@
 	result <- afterResult{slot, <-ac}
 }
 
-func testAfterQueuing(t *testing.T, delta Duration) error {
+func testAfterQueuing(delta Duration) error {
 	// make the result channel buffered because we don't want
 	// to depend on channel queueing semantics that might
 	// possibly change in the future.
diff --git a/libgo/go/time/sys_plan9.go b/libgo/go/time/sys_plan9.go
index 11365a7..9086a6e 100644
--- a/libgo/go/time/sys_plan9.go
+++ b/libgo/go/time/sys_plan9.go
@@ -19,6 +19,7 @@
 // readFile reads and returns the content of the named file.
 // It is a trivial implementation of ioutil.ReadFile, reimplemented
 // here to avoid depending on io/ioutil or os.
+// It returns an error if name exceeds maxFileSize bytes.
 func readFile(name string) ([]byte, error) {
 	f, err := syscall.Open(name, syscall.O_RDONLY)
 	if err != nil {
@@ -38,6 +39,9 @@
 		if n == 0 || err != nil {
 			break
 		}
+		if len(ret) > maxFileSize {
+			return nil, fileSizeError(name)
+		}
 	}
 	return ret, err
 }
diff --git a/libgo/go/time/sys_unix.go b/libgo/go/time/sys_unix.go
index 4c68bbd..5715275 100644
--- a/libgo/go/time/sys_unix.go
+++ b/libgo/go/time/sys_unix.go
@@ -19,6 +19,7 @@
 // readFile reads and returns the content of the named file.
 // It is a trivial implementation of ioutil.ReadFile, reimplemented
 // here to avoid depending on io/ioutil or os.
+// It returns an error if name exceeds maxFileSize bytes.
 func readFile(name string) ([]byte, error) {
 	f, err := syscall.Open(name, syscall.O_RDONLY, 0)
 	if err != nil {
@@ -38,6 +39,9 @@
 		if n == 0 || err != nil {
 			break
 		}
+		if len(ret) > maxFileSize {
+			return nil, fileSizeError(name)
+		}
 	}
 	return ret, err
 }
diff --git a/libgo/go/time/sys_windows.go b/libgo/go/time/sys_windows.go
index a4a068f..9e38165 100644
--- a/libgo/go/time/sys_windows.go
+++ b/libgo/go/time/sys_windows.go
@@ -16,6 +16,7 @@
 // readFile reads and returns the content of the named file.
 // It is a trivial implementation of ioutil.ReadFile, reimplemented
 // here to avoid depending on io/ioutil or os.
+// It returns an error if name exceeds maxFileSize bytes.
 func readFile(name string) ([]byte, error) {
 	f, err := syscall.Open(name, syscall.O_RDONLY, 0)
 	if err != nil {
@@ -35,6 +36,9 @@
 		if n == 0 || err != nil {
 			break
 		}
+		if len(ret) > maxFileSize {
+			return nil, fileSizeError(name)
+		}
 	}
 	return ret, err
 }
diff --git a/libgo/go/time/time.go b/libgo/go/time/time.go
index 10b3246..8a29eef 100644
--- a/libgo/go/time/time.go
+++ b/libgo/go/time/time.go
@@ -6,6 +6,69 @@
 //
 // The calendrical calculations always assume a Gregorian calendar, with
 // no leap seconds.
+//
+// Monotonic Clocks
+//
+// Operating systems provide both a “wall clock,” which is subject to
+// changes for clock synchronization, and a “monotonic clock,” which is
+// not. The general rule is that the wall clock is for telling time and
+// the monotonic clock is for measuring time. Rather than split the API,
+// in this package the Time returned by time.Now contains both a wall
+// clock reading and a monotonic clock reading; later time-telling
+// operations use the wall clock reading, but later time-measuring
+// operations, specifically comparisons and subtractions, use the
+// monotonic clock reading.
+//
+// For example, this code always computes a positive elapsed time of
+// approximately 20 milliseconds, even if the wall clock is changed during
+// the operation being timed:
+//
+//	start := time.Now()
+//	... operation that takes 20 milliseconds ...
+//	t := time.Now()
+//	elapsed := t.Sub(start)
+//
+// Other idioms, such as time.Since(start), time.Until(deadline), and
+// time.Now().Before(deadline), are similarly robust against wall clock
+// resets.
+//
+// The rest of this section gives the precise details of how operations
+// use monotonic clocks, but understanding those details is not required
+// to use this package.
+//
+// The Time returned by time.Now contains a monotonic clock reading.
+// If Time t has a monotonic clock reading, t.Add adds the same duration to
+// both the wall clock and monotonic clock readings to compute the result.
+// Because t.AddDate(y, m, d), t.Round(d), and t.Truncate(d) are wall time
+// computations, they always strip any monotonic clock reading from their results.
+// Because t.In, t.Local, and t.UTC are used for their effect on the interpretation
+// of the wall time, they also strip any monotonic clock reading from their results.
+// The canonical way to strip a monotonic clock reading is to use t = t.Round(0).
+//
+// If Times t and u both contain monotonic clock readings, the operations
+// t.After(u), t.Before(u), t.Equal(u), and t.Sub(u) are carried out
+// using the monotonic clock readings alone, ignoring the wall clock
+// readings. If either t or u contains no monotonic clock reading, these
+// operations fall back to using the wall clock readings.
+//
+// Because the monotonic clock reading has no meaning outside
+// the current process, the serialized forms generated by t.GobEncode,
+// t.MarshalBinary, t.MarshalJSON, and t.MarshalText omit the monotonic
+// clock reading, and t.Format provides no format for it. Similarly, the
+// constructors time.Date, time.Parse, time.ParseInLocation, and time.Unix,
+// as well as the unmarshalers t.GobDecode, t.UnmarshalBinary.
+// t.UnmarshalJSON, and t.UnmarshalText always create times with
+// no monotonic clock reading.
+//
+// Note that the Go == operator compares not just the time instant but
+// also the Location and the monotonic clock reading. See the
+// documentation for the Time type for a discussion of equality
+// testing for Time values.
+//
+// For debugging, the result of t.String does include the monotonic
+// clock reading if present. If t != u because of different monotonic clock readings,
+// that difference will be visible when printing t.String() and u.String().
+//
 package time
 
 import "errors"
@@ -14,8 +77,11 @@
 //
 // Programs using times should typically store and pass them as values,
 // not pointers. That is, time variables and struct fields should be of
-// type time.Time, not *time.Time. A Time value can be used by
-// multiple goroutines simultaneously.
+// type time.Time, not *time.Time.
+//
+// A Time value can be used by multiple goroutines simultaneously except
+// that the methods GobDecode, UnmarshalBinary, UnmarshalJSON and
+// UnmarshalText are not concurrency-safe.
 //
 // Time instants can be compared using the Before, After, and Equal methods.
 // The Sub method subtracts two instants, producing a Duration.
@@ -33,19 +99,34 @@
 // computations described in earlier paragraphs.
 //
 // Note that the Go == operator compares not just the time instant but also the
-// Location. Therefore, Time values should not be used as map or database keys
-// without first guaranteeing that the identical Location has been set for all
-// values, which can be achieved through use of the UTC or Local method.
+// Location and the monotonic clock reading. Therefore, Time values should not
+// be used as map or database keys without first guaranteeing that the
+// identical Location has been set for all values, which can be achieved
+// through use of the UTC or Local method, and that the monotonic clock reading
+// has been stripped by setting t = t.Round(0). In general, prefer t.Equal(u)
+// to t == u, since t.Equal uses the most accurate comparison available and
+// correctly handles the case when only one of its arguments has a monotonic
+// clock reading.
+//
+// In addition to the required “wall clock” reading, a Time may contain an optional
+// reading of the current process's monotonic clock, to provide additional precision
+// for comparison or subtraction.
+// See the “Monotonic Clocks” section in the package documentation for details.
 //
 type Time struct {
-	// sec gives the number of seconds elapsed since
-	// January 1, year 1 00:00:00 UTC.
-	sec int64
-
-	// nsec specifies a non-negative nanosecond
-	// offset within the second named by Seconds.
-	// It must be in the range [0, 999999999].
-	nsec int32
+	// wall and ext encode the wall time seconds, wall time nanoseconds,
+	// and optional monotonic clock reading in nanoseconds.
+	//
+	// From high to low bit position, wall encodes a 1-bit flag (hasMonotonic),
+	// a 33-bit seconds field, and a 30-bit wall time nanoseconds field.
+	// The nanoseconds field is in the range [0, 999999999].
+	// If the hasMonotonic bit is 0, then the 33-bit field must be zero
+	// and the full signed 64-bit wall seconds since Jan 1 year 1 is stored in ext.
+	// If the hasMonotonic bit is 1, then the 33-bit field holds a 33-bit
+	// unsigned wall seconds since Jan 1 year 1885, and ext holds a
+	// signed 64-bit monotonic clock reading, nanoseconds since process start.
+	wall uint64
+	ext  int64
 
 	// loc specifies the Location that should be used to
 	// determine the minute, hour, month, day, and year
@@ -55,29 +136,124 @@
 	loc *Location
 }
 
+const (
+	hasMonotonic = 1 << 63
+	maxWall      = wallToInternal + (1<<33 - 1) // year 2157
+	minWall      = wallToInternal               // year 1885
+	nsecMask     = 1<<30 - 1
+	nsecShift    = 30
+)
+
+// These helpers for manipulating the wall and monotonic clock readings
+// take pointer receivers, even when they don't modify the time,
+// to make them cheaper to call.
+
+// nsec returns the time's nanoseconds.
+func (t *Time) nsec() int32 {
+	return int32(t.wall & nsecMask)
+}
+
+// sec returns the time's seconds since Jan 1 year 1.
+func (t *Time) sec() int64 {
+	if t.wall&hasMonotonic != 0 {
+		return wallToInternal + int64(t.wall<<1>>(nsecShift+1))
+	}
+	return int64(t.ext)
+}
+
+// unixSec returns the time's seconds since Jan 1 1970 (Unix time).
+func (t *Time) unixSec() int64 { return t.sec() + internalToUnix }
+
+// addSec adds d seconds to the time.
+func (t *Time) addSec(d int64) {
+	if t.wall&hasMonotonic != 0 {
+		sec := int64(t.wall << 1 >> (nsecShift + 1))
+		dsec := sec + d
+		if 0 <= dsec && dsec <= 1<<33-1 {
+			t.wall = t.wall&nsecMask | uint64(dsec)<<nsecShift | hasMonotonic
+			return
+		}
+		// Wall second now out of range for packed field.
+		// Move to ext.
+		t.stripMono()
+	}
+
+	// TODO: Check for overflow.
+	t.ext += d
+}
+
+// setLoc sets the location associated with the time.
 func (t *Time) setLoc(loc *Location) {
 	if loc == &utcLoc {
 		loc = nil
 	}
+	t.stripMono()
 	t.loc = loc
 }
 
+// stripMono strips the monotonic clock reading in t.
+func (t *Time) stripMono() {
+	if t.wall&hasMonotonic != 0 {
+		t.ext = t.sec()
+		t.wall &= nsecMask
+	}
+}
+
+// setMono sets the monotonic clock reading in t.
+// If t cannot hold a monotonic clock reading,
+// because its wall time is too large,
+// setMono is a no-op.
+func (t *Time) setMono(m int64) {
+	if t.wall&hasMonotonic == 0 {
+		sec := int64(t.ext)
+		if sec < minWall || maxWall < sec {
+			return
+		}
+		t.wall |= hasMonotonic | uint64(sec-minWall)<<nsecShift
+	}
+	t.ext = m
+}
+
+// mono returns t's monotonic clock reading.
+// It returns 0 for a missing reading.
+// This function is used only for testing,
+// so it's OK that technically 0 is a valid
+// monotonic clock reading as well.
+func (t *Time) mono() int64 {
+	if t.wall&hasMonotonic == 0 {
+		return 0
+	}
+	return t.ext
+}
+
 // After reports whether the time instant t is after u.
 func (t Time) After(u Time) bool {
-	return t.sec > u.sec || t.sec == u.sec && t.nsec > u.nsec
+	if t.wall&u.wall&hasMonotonic != 0 {
+		return t.ext > u.ext
+	}
+	ts := t.sec()
+	us := u.sec()
+	return ts > us || ts == us && t.nsec() > u.nsec()
 }
 
 // Before reports whether the time instant t is before u.
 func (t Time) Before(u Time) bool {
-	return t.sec < u.sec || t.sec == u.sec && t.nsec < u.nsec
+	if t.wall&u.wall&hasMonotonic != 0 {
+		return t.ext < u.ext
+	}
+	return t.sec() < u.sec() || t.sec() == u.sec() && t.nsec() < u.nsec()
 }
 
 // Equal reports whether t and u represent the same time instant.
 // Two times can be equal even if they are in different locations.
 // For example, 6:00 +0200 CEST and 4:00 UTC are Equal.
-// Do not use == with Time values.
+// See the documentation on the Time type for the pitfalls of using == with
+// Time values; most code should use Equal instead.
 func (t Time) Equal(u Time) bool {
-	return t.sec == u.sec && t.nsec == u.nsec
+	if t.wall&u.wall&hasMonotonic != 0 {
+		return t.ext == u.ext
+	}
+	return t.sec() == u.sec() && t.nsec() == u.nsec()
 }
 
 // A Month specifies a month of the year (January = 1, ...).
@@ -162,7 +338,7 @@
 // The zero Time value does not force a specific epoch for the time
 // representation. For example, to use the Unix epoch internally, we
 // could define that to distinguish a zero value from Jan 1 1970, that
-// time would be represented by sec=-1, nsec=1e9.  However, it does
+// time would be represented by sec=-1, nsec=1e9. However, it does
 // suggest a representation, namely using 1-1-1 00:00:00 UTC as the
 // epoch, and that's what we do.
 //
@@ -194,7 +370,7 @@
 // everywhere.
 //
 // The calendar runs on an exact 400 year cycle: a 400-year calendar
-// printed for 1970-2469 will apply as well to 2370-2769.  Even the days
+// printed for 1970-2369 will apply as well to 2370-2769. Even the days
 // of the week match up. It simplifies the computations to choose the
 // cycle boundaries so that the exceptional years are always delayed as
 // long as possible. That means choosing a year equal to 1 mod 400, so
@@ -208,7 +384,7 @@
 //
 // These three considerations—choose an epoch as early as possible, that
 // uses a year equal to 1 mod 400, and that is no more than 2⁶³ seconds
-// earlier than 1970—bring us to the year -292277022399.  We refer to
+// earlier than 1970—bring us to the year -292277022399. We refer to
 // this year as the absolute zero year, and to times measured as a uint64
 // seconds since this year as absolute times.
 //
@@ -219,9 +395,9 @@
 // times.
 //
 // It is tempting to just use the year 1 as the absolute epoch, defining
-// that the routines are only valid for years >= 1.  However, the
+// that the routines are only valid for years >= 1. However, the
 // routines would then be invalid when displaying the epoch in time zones
-// west of UTC, since it is year 0.  It doesn't seem tenable to say that
+// west of UTC, since it is year 0. It doesn't seem tenable to say that
 // printing the zero time correctly isn't supported in half the time
 // zones. By comparison, it's reasonable to mishandle some times in
 // the year -292277022399.
@@ -245,12 +421,15 @@
 
 	unixToInternal int64 = (1969*365 + 1969/4 - 1969/100 + 1969/400) * secondsPerDay
 	internalToUnix int64 = -unixToInternal
+
+	wallToInternal int64 = (1884*365 + 1884/4 - 1884/100 + 1884/400) * secondsPerDay
+	internalToWall int64 = -wallToInternal
 )
 
 // IsZero reports whether t represents the zero time instant,
 // January 1, year 1, 00:00:00 UTC.
 func (t Time) IsZero() bool {
-	return t.sec == 0 && t.nsec == 0
+	return t.sec() == 0 && t.nsec() == 0
 }
 
 // abs returns the time t as an absolute time, adjusted by the zone offset.
@@ -261,7 +440,7 @@
 	if l == nil || l == &localLoc {
 		l = l.get()
 	}
-	sec := t.sec + internalToUnix
+	sec := t.unixSec()
 	if l != &utcLoc {
 		if l.cacheZone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
 			sec += int64(l.cacheZone.offset)
@@ -281,7 +460,7 @@
 		l = l.get()
 	}
 	// Avoid function call if we hit the local time cache.
-	sec := t.sec + internalToUnix
+	sec := t.unixSec()
 	if l != &utcLoc {
 		if l.cacheZone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
 			name = l.cacheZone.name
@@ -425,7 +604,7 @@
 // Nanosecond returns the nanosecond offset within the second specified by t,
 // in the range [0, 999999999].
 func (t Time) Nanosecond() int {
-	return int(t.nsec)
+	return int(t.nsec())
 }
 
 // YearDay returns the day of the year specified by t, in the range [1,365] for non-leap years,
@@ -543,8 +722,8 @@
 }
 
 // fmtFrac formats the fraction of v/10**prec (e.g., ".12345") into the
-// tail of buf, omitting trailing zeros.  it omits the decimal
-// point too when the fraction is 0.  It returns the index where the
+// tail of buf, omitting trailing zeros. it omits the decimal
+// point too when the fraction is 0. It returns the index where the
 // output bytes begin and the value v/10**prec.
 func fmtFrac(buf []byte, v uint64, prec int) (nw int, nv uint64) {
 	// Omit trailing zeros up to and including decimal point.
@@ -616,18 +795,73 @@
 	return float64(hour) + float64(nsec)/(60*60*1e9)
 }
 
+// Truncate returns the result of rounding d toward zero to a multiple of m.
+// If m <= 0, Truncate returns d unchanged.
+func (d Duration) Truncate(m Duration) Duration {
+	if m <= 0 {
+		return d
+	}
+	return d - d%m
+}
+
+// lessThanHalf reports whether x+x < y but avoids overflow,
+// assuming x and y are both positive (Duration is signed).
+func lessThanHalf(x, y Duration) bool {
+	return uint64(x)+uint64(x) < uint64(y)
+}
+
+// Round returns the result of rounding d to the nearest multiple of m.
+// The rounding behavior for halfway values is to round away from zero.
+// If the result exceeds the maximum (or minimum)
+// value that can be stored in a Duration,
+// Round returns the maximum (or minimum) duration.
+// If m <= 0, Round returns d unchanged.
+func (d Duration) Round(m Duration) Duration {
+	if m <= 0 {
+		return d
+	}
+	r := d % m
+	if d < 0 {
+		r = -r
+		if lessThanHalf(r, m) {
+			return d + r
+		}
+		if d1 := d - m + r; d1 < d {
+			return d1
+		}
+		return minDuration // overflow
+	}
+	if lessThanHalf(r, m) {
+		return d - r
+	}
+	if d1 := d + m - r; d1 > d {
+		return d1
+	}
+	return maxDuration // overflow
+}
+
 // Add returns the time t+d.
 func (t Time) Add(d Duration) Time {
-	t.sec += int64(d / 1e9)
-	nsec := t.nsec + int32(d%1e9)
+	dsec := int64(d / 1e9)
+	nsec := t.nsec() + int32(d%1e9)
 	if nsec >= 1e9 {
-		t.sec++
+		dsec++
 		nsec -= 1e9
 	} else if nsec < 0 {
-		t.sec--
+		dsec--
 		nsec += 1e9
 	}
-	t.nsec = nsec
+	t.wall = t.wall&^nsecMask | uint64(nsec) // update nsec
+	t.addSec(dsec)
+	if t.wall&hasMonotonic != 0 {
+		te := t.ext + int64(d)
+		if d < 0 && te > int64(t.ext) || d > 0 && te < int64(t.ext) {
+			// Monotonic clock reading now out of range; degrade to wall-only.
+			t.stripMono()
+		} else {
+			t.ext = te
+		}
+	}
 	return t
 }
 
@@ -636,7 +870,19 @@
 // will be returned.
 // To compute t-d for a duration d, use t.Add(-d).
 func (t Time) Sub(u Time) Duration {
-	d := Duration(t.sec-u.sec)*Second + Duration(t.nsec-u.nsec)
+	if t.wall&u.wall&hasMonotonic != 0 {
+		te := int64(t.ext)
+		ue := int64(u.ext)
+		d := Duration(te - ue)
+		if d < 0 && te > ue {
+			return maxDuration // t - u is positive out of range
+		}
+		if d > 0 && te < ue {
+			return minDuration // t - u is negative out of range
+		}
+		return d
+	}
+	d := Duration(t.sec()-u.sec())*Second + Duration(t.nsec()-u.nsec())
 	// Check for overflow or underflow.
 	switch {
 	case u.Add(d).Equal(t):
@@ -671,7 +917,7 @@
 func (t Time) AddDate(years int, months int, days int) Time {
 	year, month, day := t.Date()
 	hour, min, sec := t.Clock()
-	return Date(year+years, month+Month(months), day+days, hour, min, sec, int(t.nsec), t.Location())
+	return Date(year+years, month+Month(months), day+days, hour, min, sec, int(t.nsec()), t.Location())
 }
 
 const (
@@ -718,7 +964,7 @@
 
 	// Cut off years within a 4-year cycle.
 	// The last year is a leap year, so on the last day of that year,
-	// day / 365 will be 4 instead of 3.  Cut it back down to 3
+	// day / 365 will be 4 instead of 3. Cut it back down to 3
 	// by subtracting n>>2.
 	n = d / 365
 	n -= n >> 2
@@ -791,12 +1037,20 @@
 }
 
 // Provided by package runtime.
-func now() (sec int64, nsec int32)
+func now() (sec int64, nsec int32, mono int64)
 
 // Now returns the current local time.
 func Now() Time {
-	sec, nsec := now()
-	return Time{sec + unixToInternal, nsec, Local}
+	sec, nsec, mono := now()
+	sec += unixToInternal - minWall
+	if uint64(sec)>>33 != 0 {
+		return Time{uint64(nsec), sec + minWall, Local}
+	}
+	return Time{hasMonotonic | uint64(sec)<<nsecShift | uint64(nsec), mono, Local}
+}
+
+func unixTime(sec int64, nsec int32) Time {
+	return Time{uint64(nsec), sec + unixToInternal, Local}
 }
 
 // UTC returns t with the location set to UTC.
@@ -834,14 +1088,14 @@
 // Zone computes the time zone in effect at time t, returning the abbreviated
 // name of the zone (such as "CET") and its offset in seconds east of UTC.
 func (t Time) Zone() (name string, offset int) {
-	name, offset, _, _, _ = t.loc.lookup(t.sec + internalToUnix)
+	name, offset, _, _, _ = t.loc.lookup(t.unixSec())
 	return
 }
 
 // Unix returns t as a Unix time, the number of seconds elapsed
 // since January 1, 1970 UTC.
 func (t Time) Unix() int64 {
-	return t.sec + internalToUnix
+	return t.unixSec()
 }
 
 // UnixNano returns t as a Unix time, the number of nanoseconds elapsed
@@ -850,7 +1104,7 @@
 // 1678 or after 2262). Note that this means the result of calling UnixNano
 // on the zero Time is undefined.
 func (t Time) UnixNano() int64 {
-	return (t.sec+internalToUnix)*1e9 + int64(t.nsec)
+	return (t.unixSec())*1e9 + int64(t.nsec())
 }
 
 const timeBinaryVersion byte = 1
@@ -873,20 +1127,22 @@
 		offsetMin = int16(offset)
 	}
 
+	sec := t.sec()
+	nsec := t.nsec()
 	enc := []byte{
 		timeBinaryVersion, // byte 0 : version
-		byte(t.sec >> 56), // bytes 1-8: seconds
-		byte(t.sec >> 48),
-		byte(t.sec >> 40),
-		byte(t.sec >> 32),
-		byte(t.sec >> 24),
-		byte(t.sec >> 16),
-		byte(t.sec >> 8),
-		byte(t.sec),
-		byte(t.nsec >> 24), // bytes 9-12: nanoseconds
-		byte(t.nsec >> 16),
-		byte(t.nsec >> 8),
-		byte(t.nsec),
+		byte(sec >> 56),   // bytes 1-8: seconds
+		byte(sec >> 48),
+		byte(sec >> 40),
+		byte(sec >> 32),
+		byte(sec >> 24),
+		byte(sec >> 16),
+		byte(sec >> 8),
+		byte(sec),
+		byte(nsec >> 24), // bytes 9-12: nanoseconds
+		byte(nsec >> 16),
+		byte(nsec >> 8),
+		byte(nsec),
 		byte(offsetMin >> 8), // bytes 13-14: zone offset in minutes
 		byte(offsetMin),
 	}
@@ -910,18 +1166,22 @@
 	}
 
 	buf = buf[1:]
-	t.sec = int64(buf[7]) | int64(buf[6])<<8 | int64(buf[5])<<16 | int64(buf[4])<<24 |
+	sec := int64(buf[7]) | int64(buf[6])<<8 | int64(buf[5])<<16 | int64(buf[4])<<24 |
 		int64(buf[3])<<32 | int64(buf[2])<<40 | int64(buf[1])<<48 | int64(buf[0])<<56
 
 	buf = buf[8:]
-	t.nsec = int32(buf[3]) | int32(buf[2])<<8 | int32(buf[1])<<16 | int32(buf[0])<<24
+	nsec := int32(buf[3]) | int32(buf[2])<<8 | int32(buf[1])<<16 | int32(buf[0])<<24
 
 	buf = buf[4:]
 	offset := int(int16(buf[1])|int16(buf[0])<<8) * 60
 
+	*t = Time{}
+	t.wall = uint64(nsec)
+	t.ext = sec
+
 	if offset == -1*60 {
 		t.setLoc(&utcLoc)
-	} else if _, localoff, _, _, _ := Local.lookup(t.sec + internalToUnix); offset == localoff {
+	} else if _, localoff, _, _, _ := Local.lookup(t.unixSec()); offset == localoff {
 		t.setLoc(Local)
 	} else {
 		t.setLoc(FixedZone("", offset))
@@ -1008,7 +1268,7 @@
 			sec--
 		}
 	}
-	return Time{sec + unixToInternal, int32(nsec), Local}
+	return unixTime(sec, int32(nsec))
 }
 
 func isLeap(year int) bool {
@@ -1117,7 +1377,7 @@
 		unix -= int64(offset)
 	}
 
-	t := Time{unix + unixToInternal, int32(nsec), nil}
+	t := unixTime(unix, int32(nsec))
 	t.setLoc(loc)
 	return t
 }
@@ -1130,6 +1390,7 @@
 // time. Thus, Truncate(Hour) may return a time with a non-zero
 // minute, depending on the time's Location.
 func (t Time) Truncate(d Duration) Time {
+	t.stripMono()
 	if d <= 0 {
 		return t
 	}
@@ -1146,11 +1407,12 @@
 // time. Thus, Round(Hour) may return a time with a non-zero
 // minute, depending on the time's Location.
 func (t Time) Round(d Duration) Time {
+	t.stripMono()
 	if d <= 0 {
 		return t
 	}
 	_, r := div(t, d)
-	if r+r < d {
+	if lessThanHalf(r, d) {
 		return t.Add(-r)
 	}
 	return t.Add(d - r)
@@ -1161,15 +1423,16 @@
 // but it's still here in case we change our minds.
 func div(t Time, d Duration) (qmod2 int, r Duration) {
 	neg := false
-	nsec := t.nsec
-	if t.sec < 0 {
+	nsec := t.nsec()
+	sec := t.sec()
+	if sec < 0 {
 		// Operate on absolute value.
 		neg = true
-		t.sec = -t.sec
+		sec = -sec
 		nsec = -nsec
 		if nsec < 0 {
 			nsec += 1e9
-			t.sec-- // t.sec >= 1 before the -- so safe
+			sec-- // sec >= 1 before the -- so safe
 		}
 	}
 
@@ -1182,8 +1445,8 @@
 	// Special case: d is a multiple of 1 second.
 	case d%Second == 0:
 		d1 := int64(d / Second)
-		qmod2 = int(t.sec/d1) & 1
-		r = Duration(t.sec%d1)*Second + Duration(nsec)
+		qmod2 = int(sec/d1) & 1
+		r = Duration(sec%d1)*Second + Duration(nsec)
 
 	// General case.
 	// This could be faster if more cleverness were applied,
@@ -1191,7 +1454,7 @@
 	// No one will care about these cases.
 	default:
 		// Compute nanoseconds as 128-bit number.
-		sec := uint64(t.sec)
+		sec := uint64(sec)
 		tmp := (sec >> 32) * 1e9
 		u1 := tmp >> 32
 		u0 := tmp << 32
diff --git a/libgo/go/time/time_test.go b/libgo/go/time/time_test.go
index 2922560..dba8e0d 100644
--- a/libgo/go/time/time_test.go
+++ b/libgo/go/time/time_test.go
@@ -11,7 +11,9 @@
 	"fmt"
 	"math/big"
 	"math/rand"
+	"os"
 	"runtime"
+	"strings"
 	"testing"
 	"testing/quick"
 	. "time"
@@ -231,6 +233,7 @@
 	{Date(-1, January, 1, 12, 15, 31, 5e8, UTC), 3},
 	{Date(2012, January, 1, 12, 15, 30, 5e8, UTC), Second},
 	{Date(2012, January, 1, 12, 15, 31, 5e8, UTC), Second},
+	{Unix(-19012425939, 649146258), 7435029458905025217}, // 5.8*d rounds to 6*d, but .8*d+.8*d < 0 < d
 }
 
 func TestTruncateRound(t *testing.T) {
@@ -1056,6 +1059,66 @@
 	}
 }
 
+var durationTruncateTests = []struct {
+	d    Duration
+	m    Duration
+	want Duration
+}{
+	{0, Second, 0},
+	{Minute, -7 * Second, Minute},
+	{Minute, 0, Minute},
+	{Minute, 1, Minute},
+	{Minute + 10*Second, 10 * Second, Minute + 10*Second},
+	{2*Minute + 10*Second, Minute, 2 * Minute},
+	{10*Minute + 10*Second, 3 * Minute, 9 * Minute},
+	{Minute + 10*Second, Minute + 10*Second + 1, 0},
+	{Minute + 10*Second, Hour, 0},
+	{-Minute, Second, -Minute},
+	{-10 * Minute, 3 * Minute, -9 * Minute},
+	{-10 * Minute, Hour, 0},
+}
+
+func TestDurationTruncate(t *testing.T) {
+	for _, tt := range durationTruncateTests {
+		if got := tt.d.Truncate(tt.m); got != tt.want {
+			t.Errorf("Duration(%s).Truncate(%s) = %s; want: %s", tt.d, tt.m, got, tt.want)
+		}
+	}
+}
+
+var durationRoundTests = []struct {
+	d    Duration
+	m    Duration
+	want Duration
+}{
+	{0, Second, 0},
+	{Minute, -11 * Second, Minute},
+	{Minute, 0, Minute},
+	{Minute, 1, Minute},
+	{2 * Minute, Minute, 2 * Minute},
+	{2*Minute + 10*Second, Minute, 2 * Minute},
+	{2*Minute + 30*Second, Minute, 3 * Minute},
+	{2*Minute + 50*Second, Minute, 3 * Minute},
+	{-Minute, 1, -Minute},
+	{-2 * Minute, Minute, -2 * Minute},
+	{-2*Minute - 10*Second, Minute, -2 * Minute},
+	{-2*Minute - 30*Second, Minute, -3 * Minute},
+	{-2*Minute - 50*Second, Minute, -3 * Minute},
+	{8e18, 3e18, 9e18},
+	{9e18, 5e18, 1<<63 - 1},
+	{-8e18, 3e18, -9e18},
+	{-9e18, 5e18, -1 << 63},
+	{3<<61 - 1, 3 << 61, 3 << 61},
+}
+
+func TestDurationRound(t *testing.T) {
+	for _, tt := range durationRoundTests {
+		if got := tt.d.Round(tt.m); got != tt.want {
+			t.Errorf("Duration(%s).Round(%s) = %s; want: %s", tt.d, tt.m, got, tt.want)
+		}
+	}
+}
+
 var defaultLocTests = []struct {
 	name string
 	f    func(t1, t2 Time) bool
@@ -1254,3 +1317,14 @@
 		t.Errorf("zero month = %q; want %q", got, want)
 	}
 }
+
+func TestReadFileLimit(t *testing.T) {
+	const zero = "/dev/zero"
+	if _, err := os.Stat(zero); err != nil {
+		t.Skip("skipping test without a /dev/zero")
+	}
+	_, err := ReadFile(zero)
+	if err == nil || !strings.Contains(err.Error(), "is too large") {
+		t.Errorf("readFile(%q) error = %v; want error containing 'is too large'", zero, err)
+	}
+}
diff --git a/libgo/go/time/zoneinfo.go b/libgo/go/time/zoneinfo.go
index fb0aa39..f4d4df9 100644
--- a/libgo/go/time/zoneinfo.go
+++ b/libgo/go/time/zoneinfo.go
@@ -5,6 +5,7 @@
 package time
 
 import (
+	"errors"
 	"sync"
 	"syscall"
 )
@@ -81,7 +82,7 @@
 }
 
 // String returns a descriptive name for the time zone information,
-// corresponding to the argument to LoadLocation.
+// corresponding to the name argument to LoadLocation or FixedZone.
 func (l *Location) String() string {
 	return l.get().name
 }
@@ -256,7 +257,10 @@
 // NOTE(rsc): Eventually we will need to accept the POSIX TZ environment
 // syntax too, but I don't feel like implementing it today.
 
-var zoneinfo, _ = syscall.Getenv("ZONEINFO")
+var errLocation = errors.New("time: invalid location name")
+
+var zoneinfo *string
+var zoneinfoOnce sync.Once
 
 // LoadLocation returns the Location with the given name.
 //
@@ -279,11 +283,33 @@
 	if name == "Local" {
 		return Local, nil
 	}
-	if zoneinfo != "" {
-		if z, err := loadZoneFile(zoneinfo, name); err == nil {
+	if containsDotDot(name) || name[0] == '/' || name[0] == '\\' {
+		// No valid IANA Time Zone name contains a single dot,
+		// much less dot dot. Likewise, none begin with a slash.
+		return nil, errLocation
+	}
+	zoneinfoOnce.Do(func() {
+		env, _ := syscall.Getenv("ZONEINFO")
+		zoneinfo = &env
+	})
+	if zoneinfo != nil && *zoneinfo != "" {
+		if z, err := loadZoneFile(*zoneinfo, name); err == nil {
 			z.name = name
 			return z, nil
 		}
 	}
 	return loadLocation(name)
 }
+
+// containsDotDot reports whether s contains "..".
+func containsDotDot(s string) bool {
+	if len(s) < 2 {
+		return false
+	}
+	for i := 0; i < len(s)-1; i++ {
+		if s[i] == '.' && s[i+1] == '.' {
+			return true
+		}
+	}
+	return false
+}
diff --git a/libgo/go/time/zoneinfo_abbrs_windows.go b/libgo/go/time/zoneinfo_abbrs_windows.go
index 9425db8..db0bbfd 100644
--- a/libgo/go/time/zoneinfo_abbrs_windows.go
+++ b/libgo/go/time/zoneinfo_abbrs_windows.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// generated by genzabbrs.go from
-// http://unicode.org/cldr/data/common/supplemental/windowsZones.xml
+// Code generated by genzabbrs.go; DO NOT EDIT.
+// Based on information from http://unicode.org/cldr/data/common/supplemental/windowsZones.xml
 
 package time
 
@@ -22,124 +22,128 @@
 	"Namibia Standard Time":           {"WAT", "WAST"},    // Africa/Windhoek
 	"Aleutian Standard Time":          {"HST", "HDT"},     // America/Adak
 	"Alaskan Standard Time":           {"AKST", "AKDT"},   // America/Anchorage
-	"Tocantins Standard Time":         {"BRT", "BRT"},     // America/Araguaina
-	"Paraguay Standard Time":          {"PYT", "PYST"},    // America/Asuncion
-	"Bahia Standard Time":             {"BRT", "BRT"},     // America/Bahia
-	"SA Pacific Standard Time":        {"COT", "COT"},     // America/Bogota
-	"Argentina Standard Time":         {"ART", "ART"},     // America/Buenos_Aires
+	"Tocantins Standard Time":         {"-03", "-03"},     // America/Araguaina
+	"Paraguay Standard Time":          {"-04", "-03"},     // America/Asuncion
+	"Bahia Standard Time":             {"-03", "-03"},     // America/Bahia
+	"SA Pacific Standard Time":        {"-05", "-05"},     // America/Bogota
+	"Argentina Standard Time":         {"-03", "-03"},     // America/Buenos_Aires
 	"Eastern Standard Time (Mexico)":  {"EST", "EST"},     // America/Cancun
-	"Venezuela Standard Time":         {"VET", "VET"},     // America/Caracas
-	"SA Eastern Standard Time":        {"GFT", "GFT"},     // America/Cayenne
+	"Venezuela Standard Time":         {"-04", "-04"},     // America/Caracas
+	"SA Eastern Standard Time":        {"-03", "-03"},     // America/Cayenne
 	"Central Standard Time":           {"CST", "CDT"},     // America/Chicago
 	"Mountain Standard Time (Mexico)": {"MST", "MDT"},     // America/Chihuahua
-	"Central Brazilian Standard Time": {"AMT", "AMST"},    // America/Cuiaba
+	"Central Brazilian Standard Time": {"-04", "-03"},     // America/Cuiaba
 	"Mountain Standard Time":          {"MST", "MDT"},     // America/Denver
-	"Greenland Standard Time":         {"WGT", "WGST"},    // America/Godthab
+	"Greenland Standard Time":         {"-03", "-02"},     // America/Godthab
 	"Turks And Caicos Standard Time":  {"AST", "AST"},     // America/Grand_Turk
 	"Central America Standard Time":   {"CST", "CST"},     // America/Guatemala
 	"Atlantic Standard Time":          {"AST", "ADT"},     // America/Halifax
 	"Cuba Standard Time":              {"CST", "CDT"},     // America/Havana
 	"US Eastern Standard Time":        {"EST", "EDT"},     // America/Indianapolis
-	"SA Western Standard Time":        {"BOT", "BOT"},     // America/La_Paz
+	"SA Western Standard Time":        {"-04", "-04"},     // America/La_Paz
 	"Pacific Standard Time":           {"PST", "PDT"},     // America/Los_Angeles
 	"Central Standard Time (Mexico)":  {"CST", "CDT"},     // America/Mexico_City
-	"Saint Pierre Standard Time":      {"PMST", "PMDT"},   // America/Miquelon
-	"Montevideo Standard Time":        {"UYT", "UYT"},     // America/Montevideo
+	"Saint Pierre Standard Time":      {"-03", "-02"},     // America/Miquelon
+	"Montevideo Standard Time":        {"-03", "-03"},     // America/Montevideo
 	"Eastern Standard Time":           {"EST", "EDT"},     // America/New_York
 	"US Mountain Standard Time":       {"MST", "MST"},     // America/Phoenix
-	"Haiti Standard Time":             {"EST", "EST"},     // America/Port-au-Prince
+	"Haiti Standard Time":             {"EST", "EDT"},     // America/Port-au-Prince
+	"Magallanes Standard Time":        {"-03", "-03"},     // America/Punta_Arenas
 	"Canada Central Standard Time":    {"CST", "CST"},     // America/Regina
-	"Pacific SA Standard Time":        {"CLT", "CLST"},    // America/Santiago
-	"E. South America Standard Time":  {"BRT", "BRST"},    // America/Sao_Paulo
+	"Pacific SA Standard Time":        {"-04", "-03"},     // America/Santiago
+	"E. South America Standard Time":  {"-03", "-02"},     // America/Sao_Paulo
 	"Newfoundland Standard Time":      {"NST", "NDT"},     // America/St_Johns
 	"Pacific Standard Time (Mexico)":  {"PST", "PDT"},     // America/Tijuana
 	"Central Asia Standard Time":      {"+06", "+06"},     // Asia/Almaty
 	"Jordan Standard Time":            {"EET", "EEST"},    // Asia/Amman
-	"Arabic Standard Time":            {"AST", "AST"},     // Asia/Baghdad
-	"Azerbaijan Standard Time":        {"AZT", "AZT"},     // Asia/Baku
-	"SE Asia Standard Time":           {"ICT", "ICT"},     // Asia/Bangkok
-	"Altai Standard Time":             {"+06", "+07"},     // Asia/Barnaul
+	"Arabic Standard Time":            {"+03", "+03"},     // Asia/Baghdad
+	"Azerbaijan Standard Time":        {"+04", "+04"},     // Asia/Baku
+	"SE Asia Standard Time":           {"+07", "+07"},     // Asia/Bangkok
+	"Altai Standard Time":             {"+07", "+07"},     // Asia/Barnaul
 	"Middle East Standard Time":       {"EET", "EEST"},    // Asia/Beirut
 	"India Standard Time":             {"IST", "IST"},     // Asia/Calcutta
-	"Transbaikal Standard Time":       {"IRKT", "YAKT"},   // Asia/Chita
-	"Sri Lanka Standard Time":         {"IST", "IST"},     // Asia/Colombo
+	"Transbaikal Standard Time":       {"+09", "+09"},     // Asia/Chita
+	"Sri Lanka Standard Time":         {"+0530", "+0530"}, // Asia/Colombo
 	"Syria Standard Time":             {"EET", "EEST"},    // Asia/Damascus
-	"Bangladesh Standard Time":        {"BDT", "BDT"},     // Asia/Dhaka
-	"Arabian Standard Time":           {"GST", "GST"},     // Asia/Dubai
+	"Bangladesh Standard Time":        {"+06", "+06"},     // Asia/Dhaka
+	"Arabian Standard Time":           {"+04", "+04"},     // Asia/Dubai
 	"West Bank Standard Time":         {"EET", "EEST"},    // Asia/Hebron
-	"W. Mongolia Standard Time":       {"HOVT", "HOVST"},  // Asia/Hovd
-	"North Asia East Standard Time":   {"IRKT", "IRKT"},   // Asia/Irkutsk
+	"W. Mongolia Standard Time":       {"+07", "+07"},     // Asia/Hovd
+	"North Asia East Standard Time":   {"+08", "+08"},     // Asia/Irkutsk
 	"Israel Standard Time":            {"IST", "IDT"},     // Asia/Jerusalem
-	"Afghanistan Standard Time":       {"AFT", "AFT"},     // Asia/Kabul
-	"Russia Time Zone 11":             {"PETT", "PETT"},   // Asia/Kamchatka
+	"Afghanistan Standard Time":       {"+0430", "+0430"}, // Asia/Kabul
+	"Russia Time Zone 11":             {"+12", "+12"},     // Asia/Kamchatka
 	"Pakistan Standard Time":          {"PKT", "PKT"},     // Asia/Karachi
-	"Nepal Standard Time":             {"NPT", "NPT"},     // Asia/Katmandu
-	"North Asia Standard Time":        {"KRAT", "KRAT"},   // Asia/Krasnoyarsk
-	"Magadan Standard Time":           {"MAGT", "MAGT"},   // Asia/Magadan
-	"N. Central Asia Standard Time":   {"+06", "+07"},     // Asia/Novosibirsk
+	"Nepal Standard Time":             {"+0545", "+0545"}, // Asia/Katmandu
+	"North Asia Standard Time":        {"+07", "+07"},     // Asia/Krasnoyarsk
+	"Magadan Standard Time":           {"+11", "+11"},     // Asia/Magadan
+	"N. Central Asia Standard Time":   {"+07", "+07"},     // Asia/Novosibirsk
+	"Omsk Standard Time":              {"+06", "+06"},     // Asia/Omsk
 	"North Korea Standard Time":       {"KST", "KST"},     // Asia/Pyongyang
-	"Myanmar Standard Time":           {"MMT", "MMT"},     // Asia/Rangoon
-	"Arab Standard Time":              {"AST", "AST"},     // Asia/Riyadh
-	"Sakhalin Standard Time":          {"SAKT", "SAKT"},   // Asia/Sakhalin
+	"Myanmar Standard Time":           {"+0630", "+0630"}, // Asia/Rangoon
+	"Arab Standard Time":              {"+03", "+03"},     // Asia/Riyadh
+	"Sakhalin Standard Time":          {"+11", "+11"},     // Asia/Sakhalin
 	"Korea Standard Time":             {"KST", "KST"},     // Asia/Seoul
 	"China Standard Time":             {"CST", "CST"},     // Asia/Shanghai
-	"Singapore Standard Time":         {"SGT", "SGT"},     // Asia/Singapore
-	"Russia Time Zone 10":             {"SRET", "SRET"},   // Asia/Srednekolymsk
+	"Singapore Standard Time":         {"+08", "+08"},     // Asia/Singapore
+	"Russia Time Zone 10":             {"+11", "+11"},     // Asia/Srednekolymsk
 	"Taipei Standard Time":            {"CST", "CST"},     // Asia/Taipei
-	"West Asia Standard Time":         {"UZT", "UZT"},     // Asia/Tashkent
-	"Georgian Standard Time":          {"GET", "GET"},     // Asia/Tbilisi
-	"Iran Standard Time":              {"IRST", "IRDT"},   // Asia/Tehran
+	"West Asia Standard Time":         {"+05", "+05"},     // Asia/Tashkent
+	"Georgian Standard Time":          {"+04", "+04"},     // Asia/Tbilisi
+	"Iran Standard Time":              {"+0330", "+0430"}, // Asia/Tehran
 	"Tokyo Standard Time":             {"JST", "JST"},     // Asia/Tokyo
-	"Tomsk Standard Time":             {"+06", "+07"},     // Asia/Tomsk
-	"Ulaanbaatar Standard Time":       {"ULAT", "ULAST"},  // Asia/Ulaanbaatar
-	"Vladivostok Standard Time":       {"VLAT", "VLAT"},   // Asia/Vladivostok
-	"Yakutsk Standard Time":           {"YAKT", "YAKT"},   // Asia/Yakutsk
-	"Ekaterinburg Standard Time":      {"YEKT", "YEKT"},   // Asia/Yekaterinburg
-	"Caucasus Standard Time":          {"AMT", "AMT"},     // Asia/Yerevan
-	"Azores Standard Time":            {"AZOT", "AZOST"},  // Atlantic/Azores
-	"Cape Verde Standard Time":        {"CVT", "CVT"},     // Atlantic/Cape_Verde
+	"Tomsk Standard Time":             {"+07", "+07"},     // Asia/Tomsk
+	"Ulaanbaatar Standard Time":       {"+08", "+08"},     // Asia/Ulaanbaatar
+	"Vladivostok Standard Time":       {"+10", "+10"},     // Asia/Vladivostok
+	"Yakutsk Standard Time":           {"+09", "+09"},     // Asia/Yakutsk
+	"Ekaterinburg Standard Time":      {"+05", "+05"},     // Asia/Yekaterinburg
+	"Caucasus Standard Time":          {"+04", "+04"},     // Asia/Yerevan
+	"Azores Standard Time":            {"-01", "+00"},     // Atlantic/Azores
+	"Cape Verde Standard Time":        {"-01", "-01"},     // Atlantic/Cape_Verde
 	"Greenwich Standard Time":         {"GMT", "GMT"},     // Atlantic/Reykjavik
 	"Cen. Australia Standard Time":    {"ACST", "ACDT"},   // Australia/Adelaide
 	"E. Australia Standard Time":      {"AEST", "AEST"},   // Australia/Brisbane
 	"AUS Central Standard Time":       {"ACST", "ACST"},   // Australia/Darwin
-	"Aus Central W. Standard Time":    {"ACWST", "ACWST"}, // Australia/Eucla
+	"Aus Central W. Standard Time":    {"+0845", "+0845"}, // Australia/Eucla
 	"Tasmania Standard Time":          {"AEST", "AEDT"},   // Australia/Hobart
-	"Lord Howe Standard Time":         {"LHST", "LHDT"},   // Australia/Lord_Howe
+	"Lord Howe Standard Time":         {"+1030", "+11"},   // Australia/Lord_Howe
 	"W. Australia Standard Time":      {"AWST", "AWST"},   // Australia/Perth
 	"AUS Eastern Standard Time":       {"AEST", "AEDT"},   // Australia/Sydney
-	"UTC":                            {"GMT", "GMT"},       // Etc/GMT
-	"UTC-11":                         {"GMT+11", "GMT+11"}, // Etc/GMT+11
-	"Dateline Standard Time":         {"GMT+12", "GMT+12"}, // Etc/GMT+12
-	"UTC-02":                         {"GMT+2", "GMT+2"},   // Etc/GMT+2
-	"UTC-08":                         {"GMT+8", "GMT+8"},   // Etc/GMT+8
-	"UTC-09":                         {"GMT+9", "GMT+9"},   // Etc/GMT+9
-	"UTC+12":                         {"GMT-12", "GMT-12"}, // Etc/GMT-12
-	"Astrakhan Standard Time":        {"+03", "+04"},       // Europe/Astrakhan
-	"W. Europe Standard Time":        {"CET", "CEST"},      // Europe/Berlin
-	"GTB Standard Time":              {"EET", "EEST"},      // Europe/Bucharest
-	"Central Europe Standard Time":   {"CET", "CEST"},      // Europe/Budapest
-	"E. Europe Standard Time":        {"EET", "EEST"},      // Europe/Chisinau
-	"Turkey Standard Time":           {"EET", "EEST"},      // Europe/Istanbul
-	"Kaliningrad Standard Time":      {"EET", "EET"},       // Europe/Kaliningrad
-	"FLE Standard Time":              {"EET", "EEST"},      // Europe/Kiev
-	"GMT Standard Time":              {"GMT", "BST"},       // Europe/London
-	"Belarus Standard Time":          {"MSK", "MSK"},       // Europe/Minsk
-	"Russian Standard Time":          {"MSK", "MSK"},       // Europe/Moscow
-	"Romance Standard Time":          {"CET", "CEST"},      // Europe/Paris
-	"Russia Time Zone 3":             {"SAMT", "SAMT"},     // Europe/Samara
-	"Central European Standard Time": {"CET", "CEST"},      // Europe/Warsaw
-	"Mauritius Standard Time":        {"MUT", "MUT"},       // Indian/Mauritius
-	"Samoa Standard Time":            {"WSST", "WSDT"},     // Pacific/Apia
-	"New Zealand Standard Time":      {"NZST", "NZDT"},     // Pacific/Auckland
-	"Bougainville Standard Time":     {"BST", "BST"},       // Pacific/Bougainville
-	"Chatham Islands Standard Time":  {"CHAST", "CHADT"},   // Pacific/Chatham
-	"Easter Island Standard Time":    {"EAST", "EASST"},    // Pacific/Easter
-	"Fiji Standard Time":             {"FJT", "FJST"},      // Pacific/Fiji
-	"Central Pacific Standard Time":  {"SBT", "SBT"},       // Pacific/Guadalcanal
-	"Hawaiian Standard Time":         {"HST", "HST"},       // Pacific/Honolulu
-	"Line Islands Standard Time":     {"LINT", "LINT"},     // Pacific/Kiritimati
-	"Marquesas Standard Time":        {"MART", "MART"},     // Pacific/Marquesas
-	"Norfolk Standard Time":          {"NFT", "NFT"},       // Pacific/Norfolk
-	"West Pacific Standard Time":     {"PGT", "PGT"},       // Pacific/Port_Moresby
-	"Tonga Standard Time":            {"TOT", "TOT"},       // Pacific/Tongatapu
+	"UTC":                            {"GMT", "GMT"},     // Etc/GMT
+	"UTC-11":                         {"-11", "-11"},     // Etc/GMT+11
+	"Dateline Standard Time":         {"-12", "-12"},     // Etc/GMT+12
+	"UTC-02":                         {"-02", "-02"},     // Etc/GMT+2
+	"UTC-08":                         {"-08", "-08"},     // Etc/GMT+8
+	"UTC-09":                         {"-09", "-09"},     // Etc/GMT+9
+	"UTC+12":                         {"+12", "+12"},     // Etc/GMT-12
+	"UTC+13":                         {"+13", "+13"},     // Etc/GMT-13
+	"Astrakhan Standard Time":        {"+04", "+04"},     // Europe/Astrakhan
+	"W. Europe Standard Time":        {"CET", "CEST"},    // Europe/Berlin
+	"GTB Standard Time":              {"EET", "EEST"},    // Europe/Bucharest
+	"Central Europe Standard Time":   {"CET", "CEST"},    // Europe/Budapest
+	"E. Europe Standard Time":        {"EET", "EEST"},    // Europe/Chisinau
+	"Turkey Standard Time":           {"+03", "+03"},     // Europe/Istanbul
+	"Kaliningrad Standard Time":      {"EET", "EET"},     // Europe/Kaliningrad
+	"FLE Standard Time":              {"EET", "EEST"},    // Europe/Kiev
+	"GMT Standard Time":              {"GMT", "BST"},     // Europe/London
+	"Belarus Standard Time":          {"+03", "+03"},     // Europe/Minsk
+	"Russian Standard Time":          {"MSK", "MSK"},     // Europe/Moscow
+	"Romance Standard Time":          {"CET", "CEST"},    // Europe/Paris
+	"Russia Time Zone 3":             {"+04", "+04"},     // Europe/Samara
+	"Saratov Standard Time":          {"+03", "+04"},     // Europe/Saratov
+	"Central European Standard Time": {"CET", "CEST"},    // Europe/Warsaw
+	"Mauritius Standard Time":        {"+04", "+04"},     // Indian/Mauritius
+	"Samoa Standard Time":            {"+13", "+14"},     // Pacific/Apia
+	"New Zealand Standard Time":      {"NZST", "NZDT"},   // Pacific/Auckland
+	"Bougainville Standard Time":     {"+11", "+11"},     // Pacific/Bougainville
+	"Chatham Islands Standard Time":  {"+1245", "+1345"}, // Pacific/Chatham
+	"Easter Island Standard Time":    {"-06", "-05"},     // Pacific/Easter
+	"Fiji Standard Time":             {"+12", "+13"},     // Pacific/Fiji
+	"Central Pacific Standard Time":  {"+11", "+11"},     // Pacific/Guadalcanal
+	"Hawaiian Standard Time":         {"HST", "HST"},     // Pacific/Honolulu
+	"Line Islands Standard Time":     {"+14", "+14"},     // Pacific/Kiritimati
+	"Marquesas Standard Time":        {"-0930", "-0930"}, // Pacific/Marquesas
+	"Norfolk Standard Time":          {"+11", "+11"},     // Pacific/Norfolk
+	"West Pacific Standard Time":     {"+10", "+10"},     // Pacific/Port_Moresby
+	"Tonga Standard Time":            {"+13", "+14"},     // Pacific/Tongatapu
 }
diff --git a/libgo/go/time/zoneinfo_plan9.go b/libgo/go/time/zoneinfo_plan9.go
index 0694f0a..26637a1 100644
--- a/libgo/go/time/zoneinfo_plan9.go
+++ b/libgo/go/time/zoneinfo_plan9.go
@@ -95,7 +95,7 @@
 
 	// Fill in the cache with information about right now,
 	// since that will be the most common lookup.
-	sec, _ := now()
+	sec, _, _ := now()
 	for i := range tx {
 		if tx[i].when <= sec && (i+1 == len(tx) || sec < tx[i+1].when) {
 			l.cacheStart = tx[i].when
diff --git a/libgo/go/time/zoneinfo_read.go b/libgo/go/time/zoneinfo_read.go
index 19cd40d..b0cd9da 100644
--- a/libgo/go/time/zoneinfo_read.go
+++ b/libgo/go/time/zoneinfo_read.go
@@ -11,6 +11,17 @@
 
 import "errors"
 
+// maxFileSize is the max permitted size of files read by readFile.
+// As reference, the zoneinfo.zip distributed by Go is ~350 KB,
+// so 10MB is overkill.
+const maxFileSize = 10 << 20
+
+type fileSizeError string
+
+func (f fileSizeError) Error() string {
+	return "time: file " + string(f) + " is too large"
+}
+
 // Copies of io.Seek* constants to avoid importing "io":
 const (
 	seekStart   = 0
@@ -188,7 +199,7 @@
 
 	// Fill in the cache with information about right now,
 	// since that will be the most common lookup.
-	sec, _ := now()
+	sec, _, _ := now()
 	for i := range tx {
 		if tx[i].when <= sec && (i+1 == len(tx) || sec < tx[i+1].when) {
 			l.cacheStart = tx[i].when
diff --git a/libgo/go/time/zoneinfo_test.go b/libgo/go/time/zoneinfo_test.go
index 5b6a4dc..8a4caa0 100644
--- a/libgo/go/time/zoneinfo_test.go
+++ b/libgo/go/time/zoneinfo_test.go
@@ -5,10 +5,56 @@
 package time_test
 
 import (
+	"fmt"
+	"os"
 	"testing"
 	"time"
 )
 
+func init() {
+	if time.ZoneinfoForTesting() != nil {
+		panic(fmt.Errorf("zoneinfo initialized before first LoadLocation"))
+	}
+}
+
+func TestEnvVarUsage(t *testing.T) {
+	time.ResetZoneinfoForTesting()
+
+	const testZoneinfo = "foo.zip"
+	const env = "ZONEINFO"
+
+	defer os.Setenv(env, os.Getenv(env))
+	os.Setenv(env, testZoneinfo)
+
+	// Result isn't important, we're testing the side effect of this command
+	time.LoadLocation("Asia/Jerusalem")
+	defer time.ResetZoneinfoForTesting()
+
+	if zoneinfo := time.ZoneinfoForTesting(); testZoneinfo != *zoneinfo {
+		t.Errorf("zoneinfo does not match env variable: got %q want %q", zoneinfo, testZoneinfo)
+	}
+}
+
+func TestLoadLocationValidatesNames(t *testing.T) {
+	time.ResetZoneinfoForTesting()
+	const env = "ZONEINFO"
+	defer os.Setenv(env, os.Getenv(env))
+	os.Setenv(env, "")
+
+	bad := []string{
+		"/usr/foo/Foo",
+		"\\UNC\foo",
+		"..",
+		"a..",
+	}
+	for _, v := range bad {
+		_, err := time.LoadLocation(v)
+		if err != time.ErrLocation {
+			t.Errorf("LoadLocation(%q) error = %v; want ErrLocation", v, err)
+		}
+	}
+}
+
 func TestVersion3(t *testing.T) {
 	t.Skip("gccgo does not use the zip file")
 	time.ForceZipFileForTesting(true)
@@ -44,8 +90,8 @@
 		{
 			"Pacific/Fakaofo",
 			1325242799,
-			"Thu, 29 Dec 2011 23:59:59 -1100 (TKT)",
-			"Sat, 31 Dec 2011 00:00:00 +1300 (TKT)",
+			"Thu, 29 Dec 2011 23:59:59 -1100 (-11)",
+			"Sat, 31 Dec 2011 00:00:00 +1300 (+13)",
 		},
 	}
 
diff --git a/libgo/go/time/zoneinfo_windows.go b/libgo/go/time/zoneinfo_windows.go
index a6e227b..c201f4b 100644
--- a/libgo/go/time/zoneinfo_windows.go
+++ b/libgo/go/time/zoneinfo_windows.go
@@ -132,7 +132,7 @@
 			day -= 7
 		}
 	}
-	return t.sec + int64(day-1)*secondsPerDay + internalToUnix
+	return t.sec() + int64(day-1)*secondsPerDay + internalToUnix
 }
 
 func initLocalFromTZI(i *syscall.Timezoneinformation) {
diff --git a/libgo/go/unicode/letter.go b/libgo/go/unicode/letter.go
index b43cc66..90b0b41 100644
--- a/libgo/go/unicode/letter.go
+++ b/libgo/go/unicode/letter.go
@@ -46,7 +46,7 @@
 
 // CaseRange represents a range of Unicode code points for simple (one
 // code point to one code point) case conversion.
-// The range runs from Lo to Hi inclusive, with a fixed stride of 1.  Deltas
+// The range runs from Lo to Hi inclusive, with a fixed stride of 1. Deltas
 // are the number to add to the code point to reach the code point for a
 // different case for that character. They may be negative. If zero, it
 // means the character is in the corresponding case. There is a special
@@ -308,7 +308,7 @@
 }
 
 // caseOrbit is defined in tables.go as []foldPair. Right now all the
-// entries fit in uint16, so use uint16.  If that changes, compilation
+// entries fit in uint16, so use uint16. If that changes, compilation
 // will fail (the constants in the composite literal will not fit in uint16)
 // and the types here can change to uint32.
 type foldPair struct {
diff --git a/libgo/go/unicode/tables.go b/libgo/go/unicode/tables.go
index 15fecd9..9032336 100644
--- a/libgo/go/unicode/tables.go
+++ b/libgo/go/unicode/tables.go
@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Generated by running
+// Code generated by maketables; DO NOT EDIT.
+// To regenerate, run:
 //	maketables --tables=all --data=http://www.unicode.org/Public/9.0.0/ucd/UnicodeData.txt --casefolding=http://www.unicode.org/Public/9.0.0/ucd/CaseFolding.txt
-// DO NOT EDIT
 
 package unicode
 
@@ -7311,34 +7311,12 @@
 // simple case folding to code points inside the category.
 // If there is no entry for a category name, there are no such points.
 var FoldCategory = map[string]*RangeTable{
-	"Common":    foldCommon,
-	"Greek":     foldGreek,
-	"Inherited": foldInherited,
-	"L":         foldL,
-	"Ll":        foldLl,
-	"Lt":        foldLt,
-	"Lu":        foldLu,
-	"M":         foldM,
-	"Mn":        foldMn,
-}
-
-var foldCommon = &RangeTable{
-	R16: []Range16{
-		{0x039c, 0x03bc, 32},
-	},
-}
-
-var foldGreek = &RangeTable{
-	R16: []Range16{
-		{0x00b5, 0x0345, 656},
-	},
-}
-
-var foldInherited = &RangeTable{
-	R16: []Range16{
-		{0x0399, 0x03b9, 32},
-		{0x1fbe, 0x1fbe, 1},
-	},
+	"L":  foldL,
+	"Ll": foldLl,
+	"Lt": foldLt,
+	"Lu": foldLu,
+	"M":  foldM,
+	"Mn": foldMn,
 }
 
 var foldL = &RangeTable{
@@ -7609,7 +7587,30 @@
 // code points outside the script that are equivalent under
 // simple case folding to code points inside the script.
 // If there is no entry for a script name, there are no such points.
-var FoldScript = map[string]*RangeTable{}
+var FoldScript = map[string]*RangeTable{
+	"Common":    foldCommon,
+	"Greek":     foldGreek,
+	"Inherited": foldInherited,
+}
+
+var foldCommon = &RangeTable{
+	R16: []Range16{
+		{0x039c, 0x03bc, 32},
+	},
+}
+
+var foldGreek = &RangeTable{
+	R16: []Range16{
+		{0x00b5, 0x0345, 656},
+	},
+}
+
+var foldInherited = &RangeTable{
+	R16: []Range16{
+		{0x0399, 0x03b9, 32},
+		{0x1fbe, 0x1fbe, 1},
+	},
+}
 
 // Range entries: 3576 16-bit, 1454 32-bit, 5030 total.
 // Range bytes: 21456 16-bit, 17448 32-bit, 38904 total.
diff --git a/libgo/godeps.sh b/libgo/godeps.sh
index 0da5d07..87cd09e 100755
--- a/libgo/godeps.sh
+++ b/libgo/godeps.sh
@@ -25,7 +25,8 @@
 files=$*
 deps=`for f in $files; do cat $f; done | 
   sed -n -e '/^import.*"/p; /^import[ 	]*(/,/^)/p' |
-  grep '"' |
+  sed -e 's/^import //' |
+  grep '^[ 	]*"' |
   grep -v '"unsafe"' |
   sed -e 's/^.*"\([^"]*\)".*$/\1/' -e 's/$/.gox/' |
   sort -u`
diff --git a/libgo/match.sh b/libgo/match.sh
index f87a51d..fac75ea 100755
--- a/libgo/match.sh
+++ b/libgo/match.sh
@@ -151,18 +151,18 @@
 		    fi
 		    match=false
 		    ;;
-		$goos | $goarch | $cgotag | $cmdlinetag | "gccgo")
+		$goos | $goarch | $cgotag | $cmdlinetag | "gccgo" | go1.[0-9])
 		    match=true
 		    ;;
-		"!"$goos | "!"$goarch | "!"$cgotag | "!"$cmdlinetag | "!gccgo")
+		"!"$goos | "!"$goarch | "!"$cgotag | "!"$cmdlinetag | "!gccgo" | "!"go1.[0-9])
 		    ;;
 		*,*)
 		    cmatch=true
 		    for ctag in `echo $tag | sed -e 's/,/ /g'`; do
 			case $ctag in
-			    $goos | $goarch | $cgotag | $cmdlinetag | "gccgo")
+			    $goos | $goarch | $cgotag | $cmdlinetag | "gccgo" | go1.[0-9])
 				;;
-			    "!"$goos | "!"$goarch | "!"$cgotag | "!"$cmdlinetag | "!gccgo")
+			    "!"$goos | "!"$goarch | "!"$cgotag | "!"$cmdlinetag | "!gccgo" | "!"go1.[0-9])
 				cmatch=false
 				;;
 			    "!"*)
diff --git a/libgo/merge.sh b/libgo/merge.sh
index bc24504..6668665 100755
--- a/libgo/merge.sh
+++ b/libgo/merge.sh
@@ -128,7 +128,7 @@
 (cd ${NEWDIR}/src && find . -name '*.go' -print) | while read f; do
   skip=false
   case "$f" in
-  ./cmd/cgo/* | ./cmd/go/* | ./cmd/gofmt/* | ./cmd/internal/browser/*)
+  ./cmd/cgo/* | ./cmd/go/* | ./cmd/gofmt/* | ./cmd/internal/browser/* | ./cmd/internal/objabi/*)
     ;;
   ./cmd/*)
     skip=true
diff --git a/libgo/misc/cgo/errors/issue18452.go b/libgo/misc/cgo/errors/issue18452.go
new file mode 100644
index 0000000..36ef7f5
--- /dev/null
+++ b/libgo/misc/cgo/errors/issue18452.go
@@ -0,0 +1,18 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 18452: show pos info in undefined name errors
+
+package p
+
+import (
+	"C"
+	"fmt"
+)
+
+func a() {
+	fmt.Println("Hello, world!")
+	C.function_that_does_not_exist() // line 16
+	C.pi                             // line 17
+}
diff --git a/libgo/misc/cgo/errors/issue18889.go b/libgo/misc/cgo/errors/issue18889.go
new file mode 100644
index 0000000..bba6b8f
--- /dev/null
+++ b/libgo/misc/cgo/errors/issue18889.go
@@ -0,0 +1,7 @@
+package main
+
+import "C"
+
+func main() {
+	_ = C.malloc // ERROR HERE
+}
diff --git a/libgo/misc/cgo/errors/ptr.go b/libgo/misc/cgo/errors/ptr.go
index 4dafbdf..3e11766 100644
--- a/libgo/misc/cgo/errors/ptr.go
+++ b/libgo/misc/cgo/errors/ptr.go
@@ -343,6 +343,14 @@
 		body:    `var b C.char; p := &b; C.f((*C.u)(unsafe.Pointer(&p)))`,
 		fail:    false,
 	},
+	{
+		// Issue #21306.
+		name:    "preempt-during-call",
+		c:       `void f() {}`,
+		imports: []string{"runtime", "sync"},
+		body:    `var wg sync.WaitGroup; wg.Add(100); for i := 0; i < 100; i++ { go func(i int) { for j := 0; j < 100; j++ { C.f(); runtime.GOMAXPROCS(i) }; wg.Done() }(i) }; wg.Wait()`,
+		fail:    false,
+	},
 }
 
 func main() {
diff --git a/libgo/misc/cgo/errors/test.bash b/libgo/misc/cgo/errors/test.bash
index 05261e9..ed0b094 100755
--- a/libgo/misc/cgo/errors/test.bash
+++ b/libgo/misc/cgo/errors/test.bash
@@ -17,7 +17,7 @@
 expect() {
 	file=$1
 	shift
-	if go build $file >errs 2>&1; then
+	if go build -gcflags=-C $file >errs 2>&1; then
 		echo 1>&2 misc/cgo/errors/test.bash: BUG: expected cgo to fail on $file but it succeeded
 		exit 1
 	fi
@@ -47,6 +47,8 @@
 check issue13830.go
 check issue16116.go
 check issue16591.go
+check issue18889.go
+expect issue18452.go issue18452.go:16 issue18452.go:17
 
 if ! go build issue14669.go; then
 	exit 1
diff --git a/libgo/misc/cgo/fortran/test.bash b/libgo/misc/cgo/fortran/test.bash
index 3d1bc9d..1e0d59e 100755
--- a/libgo/misc/cgo/fortran/test.bash
+++ b/libgo/misc/cgo/fortran/test.bash
@@ -12,7 +12,7 @@
 goos=$(go env GOOS)
 
 libext="so"
-if [ "$goos" == "darwin" ]; then
+if [ "$goos" = "darwin" ]; then
 	libext="dylib"
 fi
 
diff --git a/libgo/misc/cgo/test/cgo_test.go b/libgo/misc/cgo/test/cgo_test.go
index a6de999..f7cf6f6 100644
--- a/libgo/misc/cgo/test/cgo_test.go
+++ b/libgo/misc/cgo/test/cgo_test.go
@@ -76,5 +76,9 @@
 func TestCheckConst(t *testing.T)            { testCheckConst(t) }
 func Test17537(t *testing.T)                 { test17537(t) }
 func Test18126(t *testing.T)                 { test18126(t) }
+func Test20369(t *testing.T)                 { test20369(t) }
+func Test18720(t *testing.T)                 { test18720(t) }
+func Test20266(t *testing.T)                 { test20266(t) }
+func Test20129(t *testing.T)                 { test20129(t) }
 
 func BenchmarkCgoCall(b *testing.B) { benchCgoCall(b) }
diff --git a/libgo/misc/cgo/test/issue18720.go b/libgo/misc/cgo/test/issue18720.go
new file mode 100644
index 0000000..a933044
--- /dev/null
+++ b/libgo/misc/cgo/test/issue18720.go
@@ -0,0 +1,28 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgotest
+
+/*
+#define HELLO "hello"
+#define WORLD "world"
+#define HELLO_WORLD HELLO "\000" WORLD
+
+struct foo { char c; };
+#define SIZE_OF(x) sizeof(x)
+#define SIZE_OF_FOO SIZE_OF(struct foo)
+*/
+import "C"
+import "testing"
+
+func test18720(t *testing.T) {
+	if C.HELLO_WORLD != "hello\000world" {
+		t.Fatalf(`expected "hello\000world", but got %q`, C.HELLO_WORLD)
+	}
+
+	// Issue 20125.
+	if got, want := C.SIZE_OF_FOO, 1; got != want {
+		t.Errorf("C.SIZE_OF_FOO == %v, expected %v", got, want)
+	}
+}
diff --git a/libgo/misc/cgo/test/issue20129.go b/libgo/misc/cgo/test/issue20129.go
new file mode 100644
index 0000000..e69e0e1
--- /dev/null
+++ b/libgo/misc/cgo/test/issue20129.go
@@ -0,0 +1,33 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgotest
+
+/*
+int issue20129 = 0;
+typedef void issue20129Void;
+issue20129Void issue20129Foo() {
+	issue20129 = 1;
+}
+typedef issue20129Void issue20129Void2;
+issue20129Void2 issue20129Bar() {
+	issue20129 = 2;
+}
+*/
+import "C"
+import "testing"
+
+func test20129(t *testing.T) {
+	if C.issue20129 != 0 {
+		t.Fatal("test is broken")
+	}
+	C.issue20129Foo()
+	if C.issue20129 != 1 {
+		t.Errorf("got %v but expected %v", C.issue20129, 1)
+	}
+	C.issue20129Bar()
+	if C.issue20129 != 2 {
+		t.Errorf("got %v but expected %v", C.issue20129, 2)
+	}
+}
diff --git a/libgo/misc/cgo/test/issue20266.go b/libgo/misc/cgo/test/issue20266.go
new file mode 100644
index 0000000..9f95086
--- /dev/null
+++ b/libgo/misc/cgo/test/issue20266.go
@@ -0,0 +1,21 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 20266: use -I with a relative path.
+
+package cgotest
+
+/*
+#cgo CFLAGS: -I issue20266 -Iissue20266 -Ddef20266
+#include "issue20266.h"
+*/
+import "C"
+
+import "testing"
+
+func test20266(t *testing.T) {
+	if got, want := C.issue20266, 20266; got != want {
+		t.Errorf("got %d, want %d", got, want)
+	}
+}
diff --git a/libgo/misc/cgo/test/issue20266/issue20266.h b/libgo/misc/cgo/test/issue20266/issue20266.h
new file mode 100644
index 0000000..8d3258e
--- /dev/null
+++ b/libgo/misc/cgo/test/issue20266/issue20266.h
@@ -0,0 +1,9 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#define issue20266 20266
+
+#ifndef def20266
+#error "expected def20266 to be defined"
+#endif
diff --git a/libgo/misc/cgo/test/issue20369.go b/libgo/misc/cgo/test/issue20369.go
new file mode 100644
index 0000000..37b4b78
--- /dev/null
+++ b/libgo/misc/cgo/test/issue20369.go
@@ -0,0 +1,20 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgotest
+
+/*
+#define UINT64_MAX        18446744073709551615ULL
+*/
+import "C"
+import (
+	"math"
+	"testing"
+)
+
+func test20369(t *testing.T) {
+	if C.UINT64_MAX != math.MaxUint64 {
+		t.Fatalf("got %v, want %v", uint64(C.UINT64_MAX), uint64(math.MaxUint64))
+	}
+}
diff --git a/libgo/misc/cgo/test/issue6612.go b/libgo/misc/cgo/test/issue6612.go
index c337f91..15a12fa 100644
--- a/libgo/misc/cgo/test/issue6612.go
+++ b/libgo/misc/cgo/test/issue6612.go
@@ -74,18 +74,15 @@
 		}
 	}
 
-	// This would be nice, but it has never worked.
-	/*
-		if c := C.myfloat_def; c != 1.5 {
-			t.Errorf("C.myint_def = %v, want 1.5", c)
-		}
-		{
-			const c = C.myfloat_def
-			if c != 1.5 {
+	if c := C.myfloat_def; c != 1.5 {
+		t.Errorf("C.myint_def = %v, want 1.5", c)
+	}
+	{
+		const c = C.myfloat_def
+		if c != 1.5 {
 			t.Errorf("C.myint as const = %v, want 1.5", c)
-			}
 		}
-	*/
+	}
 
 	if s := C.mystring_def; s != "hello" {
 		t.Errorf("C.mystring_def = %q, want %q", s, "hello")
diff --git a/libgo/misc/cgo/testcarchive/carchive_test.go b/libgo/misc/cgo/testcarchive/carchive_test.go
index a2ad9c5..4865b80 100644
--- a/libgo/misc/cgo/testcarchive/carchive_test.go
+++ b/libgo/misc/cgo/testcarchive/carchive_test.go
@@ -120,8 +120,10 @@
 func goEnv(key string) string {
 	out, err := exec.Command("go", "env", key).Output()
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "go env %s failed:\n%s", key, err)
-		fmt.Fprintf(os.Stderr, "%s", err.(*exec.ExitError).Stderr)
+		fmt.Fprintf(os.Stderr, "go env %s failed:\n%s\n", key, err)
+		if ee, ok := err.(*exec.ExitError); ok {
+			fmt.Fprintf(os.Stderr, "%s", ee.Stderr)
+		}
 		os.Exit(2)
 	}
 	return strings.TrimSpace(string(out))
@@ -238,15 +240,7 @@
 }
 
 func TestSignalForwarding(t *testing.T) {
-	switch GOOS {
-	case "darwin":
-		switch GOARCH {
-		case "arm", "arm64":
-			t.Skipf("skipping on %s/%s; see https://golang.org/issue/13701", GOOS, GOARCH)
-		}
-	case "windows":
-		t.Skip("skipping signal test on Windows")
-	}
+	checkSignalForwardingTest(t)
 
 	defer func() {
 		os.Remove("libgo2.a")
@@ -274,32 +268,19 @@
 	cmd = exec.Command(bin[0], append(bin[1:], "1")...)
 
 	out, err := cmd.CombinedOutput()
+	t.Logf("%s", out)
+	expectSignal(t, err, syscall.SIGSEGV)
 
-	if err == nil {
-		t.Logf("%s", out)
-		t.Error("test program succeeded unexpectedly")
-	} else if ee, ok := err.(*exec.ExitError); !ok {
-		t.Logf("%s", out)
-		t.Errorf("error (%v) has type %T; expected exec.ExitError", err, err)
-	} else if ws, ok := ee.Sys().(syscall.WaitStatus); !ok {
-		t.Logf("%s", out)
-		t.Errorf("error.Sys (%v) has type %T; expected syscall.WaitStatus", ee.Sys(), ee.Sys())
-	} else if !ws.Signaled() || ws.Signal() != syscall.SIGSEGV {
-		t.Logf("%s", out)
-		t.Errorf("got %v; expected SIGSEGV", ee)
-	}
+	// Test SIGPIPE forwarding
+	cmd = exec.Command(bin[0], append(bin[1:], "3")...)
+
+	out, err = cmd.CombinedOutput()
+	t.Logf("%s", out)
+	expectSignal(t, err, syscall.SIGPIPE)
 }
 
 func TestSignalForwardingExternal(t *testing.T) {
-	switch GOOS {
-	case "darwin":
-		switch GOARCH {
-		case "arm", "arm64":
-			t.Skipf("skipping on %s/%s; see https://golang.org/issue/13701", GOOS, GOARCH)
-		}
-	case "windows":
-		t.Skip("skipping signal test on Windows")
-	}
+	checkSignalForwardingTest(t)
 
 	defer func() {
 		os.Remove("libgo2.a")
@@ -370,14 +351,7 @@
 			continue
 		}
 
-		if ee, ok := err.(*exec.ExitError); !ok {
-			t.Errorf("error (%v) has type %T; expected exec.ExitError", err, err)
-		} else if ws, ok := ee.Sys().(syscall.WaitStatus); !ok {
-			t.Errorf("error.Sys (%v) has type %T; expected syscall.WaitStatus", ee.Sys(), ee.Sys())
-		} else if !ws.Signaled() || ws.Signal() != syscall.SIGSEGV {
-			t.Errorf("got %v; expected SIGSEGV", ee)
-		} else {
-			// We got the error we expected.
+		if expectSignal(t, err, syscall.SIGSEGV) {
 			return
 		}
 	}
@@ -385,6 +359,38 @@
 	t.Errorf("program succeeded unexpectedly %d times", tries)
 }
 
+// checkSignalForwardingTest calls t.Skip if the SignalForwarding test
+// doesn't work on this platform.
+func checkSignalForwardingTest(t *testing.T) {
+	switch GOOS {
+	case "darwin":
+		switch GOARCH {
+		case "arm", "arm64":
+			t.Skipf("skipping on %s/%s; see https://golang.org/issue/13701", GOOS, GOARCH)
+		}
+	case "windows":
+		t.Skip("skipping signal test on Windows")
+	}
+}
+
+// expectSignal checks that err, the exit status of a test program,
+// shows a failure due to a specific signal. Returns whether we found
+// the expected signal.
+func expectSignal(t *testing.T, err error, sig syscall.Signal) bool {
+	if err == nil {
+		t.Error("test program succeeded unexpectedly")
+	} else if ee, ok := err.(*exec.ExitError); !ok {
+		t.Errorf("error (%v) has type %T; expected exec.ExitError", err, err)
+	} else if ws, ok := ee.Sys().(syscall.WaitStatus); !ok {
+		t.Errorf("error.Sys (%v) has type %T; expected syscall.WaitStatus", ee.Sys(), ee.Sys())
+	} else if !ws.Signaled() || ws.Signal() != sig {
+		t.Errorf("got %v; expected signal %v", ee, sig)
+	} else {
+		return true
+	}
+	return false
+}
+
 func TestOsSignal(t *testing.T) {
 	switch GOOS {
 	case "windows":
@@ -585,3 +591,85 @@
 	}
 	return false
 }
+
+func TestSIGPROF(t *testing.T) {
+	switch GOOS {
+	case "windows", "plan9":
+		t.Skipf("skipping SIGPROF test on %s", GOOS)
+	}
+
+	t.Parallel()
+
+	defer func() {
+		os.Remove("testp6" + exeSuffix)
+		os.Remove("libgo6.a")
+		os.Remove("libgo6.h")
+	}()
+
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo6.a", "libgo6")
+	cmd.Env = gopathEnv
+	if out, err := cmd.CombinedOutput(); err != nil {
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+
+	ccArgs := append(cc, "-o", "testp6"+exeSuffix, "main6.c", "libgo6.a")
+	if runtime.Compiler == "gccgo" {
+		ccArgs = append(ccArgs, "-lgo")
+	}
+	if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+
+	argv := cmdToRun("./testp6")
+	cmd = exec.Command(argv[0], argv[1:]...)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+}
+
+// TestCompileWithoutShared tests that if we compile code without the
+// -shared option, we can put it into an archive. When we use the go
+// tool with -buildmode=c-archive, it passes -shared to the compiler,
+// so we override that. The go tool doesn't work this way, but Bazel
+// will likely do it in the future. And it ought to work. This test
+// was added because at one time it did not work on PPC GNU/Linux.
+func TestCompileWithoutShared(t *testing.T) {
+	// For simplicity, reuse the signal forwarding test.
+	checkSignalForwardingTest(t)
+
+	defer func() {
+		os.Remove("libgo2.a")
+		os.Remove("libgo2.h")
+	}()
+
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-gcflags=-shared=false", "-o", "libgo2.a", "libgo2")
+	cmd.Env = gopathEnv
+	t.Log(cmd.Args)
+	out, err := cmd.CombinedOutput()
+	t.Logf("%s", out)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	exe := "./testnoshared" + exeSuffix
+	ccArgs := append(cc, "-o", exe, "main5.c", "libgo2.a")
+	if runtime.Compiler == "gccgo" {
+		ccArgs = append(ccArgs, "-lgo")
+	}
+	t.Log(ccArgs)
+	out, err = exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput()
+	t.Logf("%s", out)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(exe)
+
+	binArgs := append(cmdToRun(exe), "3")
+	t.Log(binArgs)
+	out, err = exec.Command(binArgs[0], binArgs[1:]...).CombinedOutput()
+	t.Logf("%s", out)
+	expectSignal(t, err, syscall.SIGPIPE)
+}
diff --git a/libgo/misc/cgo/testcarchive/main2.c b/libgo/misc/cgo/testcarchive/main2.c
index 774e014..769cd49 100644
--- a/libgo/misc/cgo/testcarchive/main2.c
+++ b/libgo/misc/cgo/testcarchive/main2.c
@@ -17,6 +17,7 @@
 #include <unistd.h>
 #include <sched.h>
 #include <time.h>
+#include <errno.h>
 
 #include "libgo2.h"
 
@@ -26,6 +27,7 @@
 }
 
 static volatile sig_atomic_t sigioSeen;
+static volatile sig_atomic_t sigpipeSeen;
 
 // Use up some stack space.
 static void recur(int i, char *p) {
@@ -37,6 +39,10 @@
 	}
 }
 
+static void pipeHandler(int signo, siginfo_t* info, void* ctxt) {
+	sigpipeSeen = 1;
+}
+
 // Signal handler that uses up more stack space than a goroutine will have.
 static void ioHandler(int signo, siginfo_t* info, void* ctxt) {
 	char a[1024];
@@ -106,6 +112,10 @@
 		die("sigaction");
 	}
 
+	sa.sa_sigaction = pipeHandler;
+	if (sigaction(SIGPIPE, &sa, NULL) < 0) {
+		die("sigaction");
+	}
 }
 
 int main(int argc, char** argv) {
@@ -167,7 +177,30 @@
 		nanosleep(&ts, NULL);
 		i++;
 		if (i > 5000) {
-			fprintf(stderr, "looping too long waiting for signal\n");
+			fprintf(stderr, "looping too long waiting for SIGIO\n");
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	if (verbose) {
+		printf("provoking SIGPIPE\n");
+	}
+
+	GoRaiseSIGPIPE();
+
+	if (verbose) {
+		printf("waiting for sigpipeSeen\n");
+	}
+
+	// Wait until the signal has been delivered.
+	i = 0;
+	while (!sigpipeSeen) {
+		ts.tv_sec = 0;
+		ts.tv_nsec = 1000000;
+		nanosleep(&ts, NULL);
+		i++;
+		if (i > 5000) {
+			fprintf(stderr, "looping too long waiting for SIGPIPE\n");
 			exit(EXIT_FAILURE);
 		}
 	}
diff --git a/libgo/misc/cgo/testcarchive/main3.c b/libgo/misc/cgo/testcarchive/main3.c
index 0a6c0d3..60a16cf 100644
--- a/libgo/misc/cgo/testcarchive/main3.c
+++ b/libgo/misc/cgo/testcarchive/main3.c
@@ -11,6 +11,7 @@
 #include <string.h>
 #include <time.h>
 #include <sched.h>
+#include <unistd.h>
 
 #include "libgo3.h"
 
@@ -25,6 +26,31 @@
 	sigioSeen = 1;
 }
 
+// Set up the SIGPIPE signal handler in a high priority constructor, so
+// that it is installed before the Go code starts.
+
+static void pipeHandler(int signo, siginfo_t* info, void* ctxt) {
+	const char *s = "unexpected SIGPIPE\n";
+	write(2, s, strlen(s));
+	exit(EXIT_FAILURE);
+}
+
+static void init(void) __attribute__ ((constructor (200)));
+
+static void init() {
+    struct sigaction sa;
+
+	memset(&sa, 0, sizeof sa);
+	sa.sa_sigaction = pipeHandler;
+	if (sigemptyset(&sa.sa_mask) < 0) {
+		die("sigemptyset");
+	}
+	sa.sa_flags = SA_SIGINFO;
+	if (sigaction(SIGPIPE, &sa, NULL) < 0) {
+		die("sigaction");
+	}
+}
+
 int main(int argc, char** argv) {
 	int verbose;
 	struct sigaction sa;
@@ -35,6 +61,14 @@
 	setvbuf(stdout, NULL, _IONBF, 0);
 
 	if (verbose) {
+		printf("raising SIGPIPE\n");
+	}
+
+	// Test that the Go runtime handles SIGPIPE, even if we installed
+	// a non-default SIGPIPE handler before the runtime initializes.
+	ProvokeSIGPIPE();
+
+	if (verbose) {
 		printf("calling sigaction\n");
 	}
 
diff --git a/libgo/misc/cgo/testcarchive/main5.c b/libgo/misc/cgo/testcarchive/main5.c
index 9fadf08..2437bf0 100644
--- a/libgo/misc/cgo/testcarchive/main5.c
+++ b/libgo/misc/cgo/testcarchive/main5.c
@@ -68,6 +68,24 @@
 
 			break;
 		}
+		case 3: {
+			if (verbose) {
+				printf("attempting SIGPIPE\n");
+			}
+
+			int fd[2];
+			if (pipe(fd) != 0) {
+				printf("pipe(2) failed\n");
+				return 0;
+			}
+			// Close the reading end.
+			close(fd[0]);
+			// Expect that write(2) fails (EPIPE)
+			if (write(fd[1], "some data", 9) != -1) {
+				printf("write(2) unexpectedly succeeded\n");
+				return 0;
+			}
+		}
 		default:
 			printf("Unknown test: %d\n", test);
 			return 0;
diff --git a/libgo/misc/cgo/testcarchive/main6.c b/libgo/misc/cgo/testcarchive/main6.c
new file mode 100644
index 0000000..2745eb9
--- /dev/null
+++ b/libgo/misc/cgo/testcarchive/main6.c
@@ -0,0 +1,34 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that using the Go profiler in a C program does not crash.
+
+#include <stddef.h>
+#include <sys/time.h>
+
+#include "libgo6.h"
+
+int main(int argc, char **argv) {
+	struct timeval tvstart, tvnow;
+	int diff;
+
+	gettimeofday(&tvstart, NULL);
+
+	go_start_profile();
+
+	// Busy wait so we have something to profile.
+	// If we just sleep the profiling signal will never fire.
+	while (1) {
+		gettimeofday(&tvnow, NULL);
+		diff = (tvnow.tv_sec - tvstart.tv_sec) * 1000 * 1000 + (tvnow.tv_usec - tvstart.tv_usec);
+
+		// Profile frequency is 100Hz so we should definitely
+		// get a signal in 50 milliseconds.
+		if (diff > 50 * 1000)
+			break;
+	}
+
+	go_stop_profile();
+	return 0;
+}
diff --git a/libgo/misc/cgo/testcarchive/src/libgo2/libgo2.go b/libgo/misc/cgo/testcarchive/src/libgo2/libgo2.go
index fbed493..19c8e1a 100644
--- a/libgo/misc/cgo/testcarchive/src/libgo2/libgo2.go
+++ b/libgo/misc/cgo/testcarchive/src/libgo2/libgo2.go
@@ -4,6 +4,30 @@
 
 package main
 
+/*
+#include <signal.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+// Raise SIGPIPE.
+static void CRaiseSIGPIPE() {
+	int fds[2];
+
+	if (pipe(fds) == -1) {
+		perror("pipe");
+		exit(EXIT_FAILURE);
+	}
+	// Close the reader end
+	close(fds[0]);
+	// Write to the writer end to provoke a SIGPIPE
+	if (write(fds[1], "some data", 9) != -1) {
+		fprintf(stderr, "write to a closed pipe succeeded\n");
+		exit(EXIT_FAILURE);
+	}
+	close(fds[1]);
+}
+*/
 import "C"
 
 import (
@@ -46,5 +70,11 @@
 func Noop() {
 }
 
+// Raise SIGPIPE.
+//export GoRaiseSIGPIPE
+func GoRaiseSIGPIPE() {
+	C.CRaiseSIGPIPE()
+}
+
 func main() {
 }
diff --git a/libgo/misc/cgo/testcarchive/src/libgo3/libgo3.go b/libgo/misc/cgo/testcarchive/src/libgo3/libgo3.go
index 94e5d21..e276a3c 100644
--- a/libgo/misc/cgo/testcarchive/src/libgo3/libgo3.go
+++ b/libgo/misc/cgo/testcarchive/src/libgo3/libgo3.go
@@ -40,5 +40,17 @@
 	}
 }
 
+// ProvokeSIGPIPE provokes a kernel-initiated SIGPIPE.
+//export ProvokeSIGPIPE
+func ProvokeSIGPIPE() {
+	r, w, err := os.Pipe()
+	if err != nil {
+		panic(err)
+	}
+	r.Close()
+	defer w.Close()
+	w.Write([]byte("some data"))
+}
+
 func main() {
 }
diff --git a/libgo/misc/cgo/testcarchive/src/libgo6/sigprof.go b/libgo/misc/cgo/testcarchive/src/libgo6/sigprof.go
new file mode 100644
index 0000000..4cb05dc
--- /dev/null
+++ b/libgo/misc/cgo/testcarchive/src/libgo6/sigprof.go
@@ -0,0 +1,25 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"io/ioutil"
+	"runtime/pprof"
+)
+
+import "C"
+
+//export go_start_profile
+func go_start_profile() {
+	pprof.StartCPUProfile(ioutil.Discard)
+}
+
+//export go_stop_profile
+func go_stop_profile() {
+	pprof.StopCPUProfile()
+}
+
+func main() {
+}
diff --git a/libgo/misc/cgo/testcshared/main0.c b/libgo/misc/cgo/testcshared/main0.c
index 1274b89..39ef7e3 100644
--- a/libgo/misc/cgo/testcshared/main0.c
+++ b/libgo/misc/cgo/testcshared/main0.c
@@ -12,6 +12,7 @@
 //   int8_t DidInitRun();
 //   int8_t DidMainRun();
 //   int32_t FromPkg();
+//   uint32_t Divu(uint32_t, uint32_t);
 int main(void) {
   int8_t ran_init = DidInitRun();
   if (!ran_init) {
@@ -30,6 +31,11 @@
     fprintf(stderr, "ERROR: FromPkg=%d, want %d\n", from_pkg, 1024);
     return 1;
   }
+  uint32_t divu = Divu(2264, 31);
+  if (divu != 73) {
+    fprintf(stderr, "ERROR: Divu(2264, 31)=%d, want %d\n", divu, 73);
+    return 1;
+  }
   // test.bash looks for "PASS" to ensure this program has reached the end. 
   printf("PASS\n");
   return 0;
diff --git a/libgo/misc/cgo/testcshared/src/p/p.go b/libgo/misc/cgo/testcshared/src/p/p.go
index 82b445c..0f02cf3 100644
--- a/libgo/misc/cgo/testcshared/src/p/p.go
+++ b/libgo/misc/cgo/testcshared/src/p/p.go
@@ -8,3 +8,6 @@
 
 //export FromPkg
 func FromPkg() int32 { return 1024 }
+
+//export Divu
+func Divu(a, b uint32) uint32 { return a / b }
diff --git a/libgo/misc/cgo/testcshared/test.bash b/libgo/misc/cgo/testcshared/test.bash
index 0315fb0..315a0d4 100755
--- a/libgo/misc/cgo/testcshared/test.bash
+++ b/libgo/misc/cgo/testcshared/test.bash
@@ -27,7 +27,7 @@
 # Directory where cgo headers and outputs will be installed.
 # The installation directory format varies depending on the platform.
 installdir=pkg/${goos}_${goarch}_testcshared_shared
-if [ "${goos}" == "darwin" ]; then
+if [ "${goos}" = "darwin" ]; then
 	installdir=pkg/${goos}_${goarch}_testcshared
 fi
 
@@ -40,13 +40,13 @@
 	rm -f testp testp2 testp3 testp4 testp5
 	rm -rf pkg "${goroot}/${installdir}"
 
-	if [ "$goos" == "android" ]; then
+	if [ "$goos" = "android" ]; then
 		adb shell rm -rf "$androidpath"
 	fi
 }
 trap cleanup EXIT
 
-if [ "$goos" == "android" ]; then
+if [ "$goos" = "android" ]; then
 	adb shell mkdir -p "$androidpath"
 fi
 
@@ -69,7 +69,7 @@
 
 function binpush() {
 	bin=${1}
-	if [ "$goos" == "android" ]; then
+	if [ "$goos" = "android" ]; then
 		adb push "$bin"  "${androidpath}/${bin}" 2>/dev/null
 	fi
 }
@@ -79,7 +79,7 @@
 suffix="-installsuffix testcshared"
 
 libext="so"
-if [ "$goos" == "darwin" ]; then
+if [ "$goos" = "darwin" ]; then
 	libext="dylib"
 fi
 
@@ -89,7 +89,7 @@
 GOPATH=$(pwd) go build -buildmode=c-shared $suffix -o libgo.$libext src/libgo/libgo.go
 binpush libgo.$libext
 
-if [ "$goos" == "linux" ] || [ "$goos" == "android" ] ; then
+if [ "$goos" = "linux" ] || [ "$goos" = "android" ] ; then
     if readelf -d libgo.$libext | grep TEXTREL >/dev/null; then
         echo "libgo.$libext has TEXTREL set"
         exit 1
@@ -97,8 +97,8 @@
 fi
 
 GOGCCFLAGS=$(go env GOGCCFLAGS)
-if [ "$goos" == "android" ]; then
-	GOGCCFLAGS="${GOGCCFLAGS} -pie"
+if [ "$goos" = "android" ]; then
+	GOGCCFLAGS="${GOGCCFLAGS} -pie -fuse-ld=gold"
 fi
 
 status=0
@@ -127,7 +127,7 @@
 GOPATH=$(pwd) go build -buildmode=c-shared $suffix -o libgo2.$libext libgo2
 binpush libgo2.$libext
 linkflags="-Wl,--no-as-needed"
-if [ "$goos" == "darwin" ]; then
+if [ "$goos" = "darwin" ]; then
 	linkflags=""
 fi
 $(go env CC) ${GOGCCFLAGS} -o testp2 main2.c $linkflags libgo2.$libext
@@ -139,7 +139,7 @@
 fi
 
 # test3: tests main.main is exported on android.
-if [ "$goos" == "android" ]; then
+if [ "$goos" = "android" ]; then
 	$(go env CC) ${GOGCCFLAGS} -o testp3 main3.c -ldl
 	binpush testp3
 	output=$(run ./testp ./libgo.so)
diff --git a/libgo/misc/cgo/testplugin/src/issue19534/main.go b/libgo/misc/cgo/testplugin/src/issue19534/main.go
new file mode 100644
index 0000000..de263b6
--- /dev/null
+++ b/libgo/misc/cgo/testplugin/src/issue19534/main.go
@@ -0,0 +1,23 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "plugin"
+
+func main() {
+	p, err := plugin.Open("plugin.so")
+	if err != nil {
+		panic(err)
+	}
+
+	sym, err := p.Lookup("Foo")
+	if err != nil {
+		panic(err)
+	}
+	f := sym.(func() int)
+	if f() != 42 {
+		panic("expected f() == 42")
+	}
+}
diff --git a/libgo/misc/cgo/testplugin/src/issue19534/plugin.go b/libgo/misc/cgo/testplugin/src/issue19534/plugin.go
new file mode 100644
index 0000000..582d333
--- /dev/null
+++ b/libgo/misc/cgo/testplugin/src/issue19534/plugin.go
@@ -0,0 +1,9 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+func Foo() int {
+	return 42
+}
diff --git a/libgo/misc/cgo/testplugin/test.bash b/libgo/misc/cgo/testplugin/test.bash
index ab7430a..69df5bd 100755
--- a/libgo/misc/cgo/testplugin/test.bash
+++ b/libgo/misc/cgo/testplugin/test.bash
@@ -16,7 +16,7 @@
 
 function cleanup() {
 	rm -f plugin*.so unnamed*.so iface*.so
-	rm -rf host pkg sub iface issue18676
+	rm -rf host pkg sub iface issue18676 issue19534
 }
 trap cleanup EXIT
 
@@ -44,3 +44,9 @@
 GOPATH=$(pwd) go build -buildmode=plugin -o plugin.so src/issue18676/plugin.go
 GOPATH=$(pwd) go build -o issue18676 src/issue18676/main.go
 timeout 10s ./issue18676
+
+# Test for issue 19534 - that we can load a plugin built in a path with non-alpha
+# characters
+GOPATH=$(pwd) go build -buildmode=plugin -ldflags='-pluginpath=issue.19534' -o plugin.so src/issue19534/plugin.go
+GOPATH=$(pwd) go build -o issue19534 src/issue19534/main.go
+./issue19534
diff --git a/libgo/misc/cgo/testplugin/unnamed1.go b/libgo/misc/cgo/testplugin/unnamed1.go
index 102edaf..5c1df08 100644
--- a/libgo/misc/cgo/testplugin/unnamed1.go
+++ b/libgo/misc/cgo/testplugin/unnamed1.go
@@ -9,4 +9,15 @@
 
 func FuncInt() int { return 1 }
 
+// Add a recursive type to to check that type equality across plugins doesn't
+// crash. See https://golang.org/issues/19258
+func FuncRecursive() X { return X{} }
+
+type Y struct {
+	X *X
+}
+type X struct {
+	Y Y
+}
+
 func main() {}
diff --git a/libgo/misc/cgo/testplugin/unnamed2.go b/libgo/misc/cgo/testplugin/unnamed2.go
index 55070d5..7ef6610 100644
--- a/libgo/misc/cgo/testplugin/unnamed2.go
+++ b/libgo/misc/cgo/testplugin/unnamed2.go
@@ -9,4 +9,13 @@
 
 func FuncInt() int { return 2 }
 
+func FuncRecursive() X { return X{} }
+
+type Y struct {
+	X *X
+}
+type X struct {
+	Y Y
+}
+
 func main() {}
diff --git a/libgo/misc/cgo/testsanitizers/test.bash b/libgo/misc/cgo/testsanitizers/test.bash
index 4da8502..9f80af6 100755
--- a/libgo/misc/cgo/testsanitizers/test.bash
+++ b/libgo/misc/cgo/testsanitizers/test.bash
@@ -72,12 +72,12 @@
   goos=$(go env GOOS)
   suffix="-installsuffix testsanitizers"
   libext="so"
-  if [ "$goos" == "darwin" ]; then
+  if [ "$goos" = "darwin" ]; then
 	  libext="dylib"
   fi
   go build -msan -buildmode=c-shared $suffix -o ${TMPDIR}/libmsanshared.$libext msan_shared.go
 
-	echo 'int main() { return 0; }' > ${TMPDIR}/testmsanshared.c
+  echo 'int main() { return 0; }' > ${TMPDIR}/testmsanshared.c
   $CC $(go env GOGCCFLAGS) -fsanitize=memory -o ${TMPDIR}/testmsanshared ${TMPDIR}/testmsanshared.c ${TMPDIR}/libmsanshared.$libext
 
   if ! LD_LIBRARY_PATH=. ${TMPDIR}/testmsanshared; then
@@ -131,21 +131,43 @@
     testmsanshared
 fi
 
+testtsanshared() {
+  goos=$(go env GOOS)
+  suffix="-installsuffix tsan"
+  libext="so"
+  if [ "$goos" = "darwin" ]; then
+	  libext="dylib"
+  fi
+  go build -buildmode=c-shared $suffix -o ${TMPDIR}/libtsanshared.$libext tsan_shared.go
+
+  echo 'int main() { return 0; }' > ${TMPDIR}/testtsanshared.c
+  $CC $(go env GOGCCFLAGS) -fsanitize=thread -o ${TMPDIR}/testtsanshared ${TMPDIR}/testtsanshared.c ${TMPDIR}/libtsanshared.$libext
+
+  if ! LD_LIBRARY_PATH=. ${TMPDIR}/testtsanshared; then
+    echo "FAIL: tsan_shared"
+    status=1
+  fi
+  rm -f ${TMPDIR}/{testtsanshared,testtsanshared.c,libtsanshared.$libext}
+}
+
 if test "$tsan" = "yes"; then
     echo 'int main() { return 0; }' > ${TMPDIR}/testsanitizers$$.c
     ok=yes
     if ! $CC -fsanitize=thread ${TMPDIR}/testsanitizers$$.c -o ${TMPDIR}/testsanitizers$$ &> ${TMPDIR}/testsanitizers$$.err; then
 	ok=no
     fi
-     if grep "unrecognized" ${TMPDIR}/testsanitizers$$.err >& /dev/null; then
+    if grep "unrecognized" ${TMPDIR}/testsanitizers$$.err >& /dev/null; then
 	echo "skipping tsan tests: -fsanitize=thread not supported"
 	tsan=no
-     elif test "$ok" != "yes"; then
-	 cat ${TMPDIR}/testsanitizers$$.err
-	 echo "skipping tsan tests: -fsanitizer=thread build failed"
-	 tsan=no
-     fi
-     rm -f ${TMPDIR}/testsanitizers$$*
+    elif test "$ok" != "yes"; then
+	cat ${TMPDIR}/testsanitizers$$.err
+	echo "skipping tsan tests: -fsanitizer=thread build failed"
+	tsan=no
+    elif ! ${TMPDIR}/testsanitizers$$ 2>&1; then
+	echo "skipping tsan tests: running tsan program failed"
+	tsan=no
+    fi
+    rm -f ${TMPDIR}/testsanitizers$$*
 fi
 
 # Run a TSAN test.
@@ -177,8 +199,10 @@
     # These tests are only reliable using clang or GCC version 7 or later.
     # Otherwise runtime/cgo/libcgo.h can't tell whether TSAN is in use.
     ok=false
+    clang=false
     if ${CC} --version | grep clang >/dev/null 2>&1; then
 	ok=true
+	clang=true
     else
 	ver=$($CC -dumpversion)
 	major=$(echo $ver | sed -e 's/\([0-9]*\).*/\1/')
@@ -190,14 +214,19 @@
     fi
 
     if test "$ok" = "true"; then
-	# This test requires rebuilding os/user with -fsanitize=thread.
+	# These tests require rebuilding os/user with -fsanitize=thread.
 	testtsan tsan5.go "CGO_CFLAGS=-fsanitize=thread CGO_LDFLAGS=-fsanitize=thread" "-installsuffix=tsan"
-
-	# This test requires rebuilding runtime/cgo with -fsanitize=thread.
 	testtsan tsan6.go "CGO_CFLAGS=-fsanitize=thread CGO_LDFLAGS=-fsanitize=thread" "-installsuffix=tsan"
-
-	# This test requires rebuilding runtime/cgo with -fsanitize=thread.
 	testtsan tsan7.go "CGO_CFLAGS=-fsanitize=thread CGO_LDFLAGS=-fsanitize=thread" "-installsuffix=tsan"
+
+	# The remaining tests reportedly hang when built with GCC; issue #21196.
+	if test "$clang" = "true"; then
+	    testtsan tsan10.go "CGO_CFLAGS=-fsanitize=thread CGO_LDFLAGS=-fsanitize=thread" "-installsuffix=tsan"
+	    testtsan tsan11.go "CGO_CFLAGS=-fsanitize=thread CGO_LDFLAGS=-fsanitize=thread" "-installsuffix=tsan"
+	    testtsan tsan12.go "CGO_CFLAGS=-fsanitize=thread CGO_LDFLAGS=-fsanitize=thread" "-installsuffix=tsan"
+	fi
+
+	testtsanshared
     fi
 fi
 
diff --git a/libgo/misc/cgo/testsanitizers/tsan10.go b/libgo/misc/cgo/testsanitizers/tsan10.go
new file mode 100644
index 0000000..a40f245
--- /dev/null
+++ b/libgo/misc/cgo/testsanitizers/tsan10.go
@@ -0,0 +1,31 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// This program hung when run under the C/C++ ThreadSanitizer.
+// TSAN defers asynchronous signals until the signaled thread calls into libc.
+// Since the Go runtime makes direct futex syscalls, Go runtime threads could
+// run for an arbitrarily long time without triggering the libc interceptors.
+// See https://golang.org/issue/18717.
+
+import (
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+/*
+#cgo CFLAGS: -g -fsanitize=thread
+#cgo LDFLAGS: -g -fsanitize=thread
+*/
+import "C"
+
+func main() {
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, syscall.SIGUSR1)
+	defer signal.Stop(c)
+	syscall.Kill(syscall.Getpid(), syscall.SIGUSR1)
+	<-c
+}
diff --git a/libgo/misc/cgo/testsanitizers/tsan11.go b/libgo/misc/cgo/testsanitizers/tsan11.go
new file mode 100644
index 0000000..70ac9c8
--- /dev/null
+++ b/libgo/misc/cgo/testsanitizers/tsan11.go
@@ -0,0 +1,55 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// This program hung when run under the C/C++ ThreadSanitizer. TSAN defers
+// asynchronous signals until the signaled thread calls into libc. The runtime's
+// sysmon goroutine idles itself using direct usleep syscalls, so it could
+// run for an arbitrarily long time without triggering the libc interceptors.
+// See https://golang.org/issue/18717.
+
+import (
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+/*
+#cgo CFLAGS: -g -fsanitize=thread
+#cgo LDFLAGS: -g -fsanitize=thread
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static void raise_usr2(int signo) {
+	raise(SIGUSR2);
+}
+
+static void register_handler(int signo) {
+	struct sigaction sa;
+	memset(&sa, 0, sizeof(sa));
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_ONSTACK;
+	sa.sa_handler = raise_usr2;
+
+	if (sigaction(SIGUSR1, &sa, NULL) != 0) {
+		perror("failed to register SIGUSR1 handler");
+		exit(EXIT_FAILURE);
+	}
+}
+*/
+import "C"
+
+func main() {
+	ch := make(chan os.Signal)
+	signal.Notify(ch, syscall.SIGUSR2)
+
+	C.register_handler(C.int(syscall.SIGUSR1))
+	syscall.Kill(syscall.Getpid(), syscall.SIGUSR1)
+
+	<-ch
+}
diff --git a/libgo/misc/cgo/testsanitizers/tsan12.go b/libgo/misc/cgo/testsanitizers/tsan12.go
new file mode 100644
index 0000000..3e767ee
--- /dev/null
+++ b/libgo/misc/cgo/testsanitizers/tsan12.go
@@ -0,0 +1,35 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// This program hung when run under the C/C++ ThreadSanitizer. TSAN installs a
+// libc interceptor that writes signal handlers to a global variable within the
+// TSAN runtime instead of making a sigaction system call. A bug in
+// syscall.runtime_AfterForkInChild corrupted TSAN's signal forwarding table
+// during calls to (*os/exec.Cmd).Run, causing the parent process to fail to
+// invoke signal handlers.
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"os/signal"
+	"syscall"
+)
+
+import "C"
+
+func main() {
+	ch := make(chan os.Signal)
+	signal.Notify(ch, syscall.SIGUSR1)
+
+	if err := exec.Command("true").Run(); err != nil {
+		fmt.Fprintf(os.Stderr, "Unexpected error from `true`: %v", err)
+		os.Exit(1)
+	}
+
+	syscall.Kill(syscall.Getpid(), syscall.SIGUSR1)
+	<-ch
+}
diff --git a/libgo/misc/cgo/testsanitizers/tsan_shared.go b/libgo/misc/cgo/testsanitizers/tsan_shared.go
new file mode 100644
index 0000000..55ff67e
--- /dev/null
+++ b/libgo/misc/cgo/testsanitizers/tsan_shared.go
@@ -0,0 +1,63 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// This program failed with SIGSEGV when run under the C/C++ ThreadSanitizer.
+// The Go runtime had re-registered the C handler with the wrong flags due to a
+// typo, resulting in null pointers being passed for the info and context
+// parameters to the handler.
+
+/*
+#cgo CFLAGS: -fsanitize=thread
+#cgo LDFLAGS: -fsanitize=thread
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ucontext.h>
+
+void check_params(int signo, siginfo_t *info, void *context) {
+	ucontext_t* uc = (ucontext_t*)(context);
+
+	if (info->si_signo != signo) {
+		fprintf(stderr, "info->si_signo does not match signo.\n");
+		abort();
+	}
+
+	if (uc->uc_stack.ss_size == 0) {
+		fprintf(stderr, "uc_stack has size 0.\n");
+		abort();
+	}
+}
+
+
+// Set up the signal handler in a high priority constructor, so
+// that it is installed before the Go code starts.
+
+static void register_handler(void) __attribute__ ((constructor (200)));
+
+static void register_handler() {
+	struct sigaction sa;
+	memset(&sa, 0, sizeof(sa));
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_SIGINFO;
+	sa.sa_sigaction = check_params;
+
+	if (sigaction(SIGUSR1, &sa, NULL) != 0) {
+		perror("failed to register SIGUSR1 handler");
+		exit(EXIT_FAILURE);
+	}
+}
+*/
+import "C"
+
+import "syscall"
+
+func init() {
+	C.raise(C.int(syscall.SIGUSR1))
+}
+
+func main() {}
diff --git a/libgo/misc/cgo/testshared/shared_test.go b/libgo/misc/cgo/testshared/shared_test.go
index f0766e5..9e682a2 100644
--- a/libgo/misc/cgo/testshared/shared_test.go
+++ b/libgo/misc/cgo/testshared/shared_test.go
@@ -10,7 +10,6 @@
 	"debug/elf"
 	"encoding/binary"
 	"errors"
-	"flag"
 	"fmt"
 	"go/build"
 	"io"
@@ -166,7 +165,6 @@
 	// That won't work if GOBIN is set.
 	os.Unsetenv("GOBIN")
 
-	flag.Parse()
 	exitCode, err := testMain(m)
 	if err != nil {
 		log.Fatal(err)
@@ -402,6 +400,12 @@
 	AssertHasRPath(t, "./trivial.pie", gorootInstallDir)
 }
 
+// Build a division test program and check it runs.
+func TestDivisionExecutable(t *testing.T) {
+	goCmd(t, "install", "-linkshared", "division")
+	run(t, "division executable", "./bin/division")
+}
+
 // Build an executable that uses cgo linked against the shared runtime and check it
 // runs.
 func TestCgoExecutable(t *testing.T) {
@@ -759,6 +763,13 @@
 	}
 }
 
+func writeFile(path, content string) {
+	err := ioutil.WriteFile(path, []byte(content), 0644)
+	if err != nil {
+		log.Fatalf("ioutil.WriteFile failed: %v", err)
+	}
+}
+
 func TestABIChecking(t *testing.T) {
 	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
 	goCmd(t, "install", "-linkshared", "exe")
@@ -797,9 +808,10 @@
 	run(t, "rebuilt exe", "./bin/exe")
 
 	// If we make a change which does not break ABI (such as adding an unexported
-	// function) and rebuild libdepBase.so, exe still works.
+	// function) and rebuild libdepBase.so, exe still works, even if new function
+	// is in a file by itself.
 	resetFileStamps()
-	appendFile("src/depBase/dep.go", "func noABIBreak() {}\n")
+	writeFile("src/depBase/dep2.go", "package depBase\nfunc noABIBreak() {}\n")
 	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
 	run(t, "after non-ABI breaking change", "./bin/exe")
 }
diff --git a/libgo/misc/cgo/testshared/src/division/division.go b/libgo/misc/cgo/testshared/src/division/division.go
new file mode 100644
index 0000000..bb5fc98
--- /dev/null
+++ b/libgo/misc/cgo/testshared/src/division/division.go
@@ -0,0 +1,17 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+//go:noinline
+func div(x, y uint32) uint32 {
+	return x / y
+}
+
+func main() {
+	a := div(97, 11)
+	if a != 8 {
+		panic("FAIL")
+	}
+}
diff --git a/libgo/runtime/go-now.c b/libgo/runtime/go-now.c
index d24e6ee..13e8f51 100644
--- a/libgo/runtime/go-now.c
+++ b/libgo/runtime/go-now.c
@@ -8,13 +8,22 @@
 
 #include "runtime.h"
 
-// Return current time.  This is the implementation of time.now().
+// Return current time.  This is the implementation of time.walltime().
 
-struct time_now_ret
+struct walltime_ret
+{
+  int64_t sec;
+  int32_t nsec;
+};
+
+struct walltime_ret now() __asm__ (GOSYM_PREFIX "runtime.walltime")
+  __attribute__ ((no_split_stack));
+
+struct walltime_ret
 now()
 {
   struct timespec ts;
-  struct time_now_ret ret;
+  struct walltime_ret ret;
 
   clock_gettime (CLOCK_REALTIME, &ts);
   ret.sec = ts.tv_sec;
diff --git a/libgo/runtime/proc.c b/libgo/runtime/proc.c
index 3e3437e..e591824 100644
--- a/libgo/runtime/proc.c
+++ b/libgo/runtime/proc.c
@@ -375,6 +375,8 @@
 
 extern void kickoff(void)
   __asm__(GOSYM_PREFIX "runtime.kickoff");
+extern void minit(void)
+  __asm__(GOSYM_PREFIX "runtime.minit");
 extern void mstart1(void)
   __asm__(GOSYM_PREFIX "runtime.mstart1");
 extern void stopm(void)
@@ -476,6 +478,10 @@
 	gp->entry = nil;
 	gp->param = nil;
 
+	// We have to call minit before we call getcontext,
+	// because getcontext will copy the signal mask.
+	minit();
+
 	initcontext();
 
 	// Record top of stack for use by mcall.
diff --git a/libgo/runtime/runtime.h b/libgo/runtime/runtime.h
index 3324038..dd5a958 100644
--- a/libgo/runtime/runtime.h
+++ b/libgo/runtime/runtime.h
@@ -193,16 +193,6 @@
 };
 void	runtime_hashinit(void);
 
-void	runtime_traceback(int32)
-  __asm__ (GOSYM_PREFIX "runtime.traceback");
-void	runtime_tracebackothers(G*)
-  __asm__ (GOSYM_PREFIX "runtime.tracebackothers");
-enum
-{
-	// The maximum number of frames we print for a traceback
-	TracebackMaxFrames = 100,
-};
-
 /*
  * external data
  */
@@ -217,7 +207,6 @@
 extern	Sched*  runtime_sched;
 extern	uint32	runtime_panicking(void)
   __asm__ (GOSYM_PREFIX "runtime.getPanicking");
-extern	struct debugVars runtime_debug;
 
 extern	bool	runtime_isstarted;
 extern	bool	runtime_isarchive;
@@ -253,10 +242,6 @@
   __asm__ (GOSYM_PREFIX "runtime.schedinit");
 void	runtime_initsig(bool)
   __asm__ (GOSYM_PREFIX "runtime.initsig");
-void	runtime_goroutineheader(G*)
-  __asm__ (GOSYM_PREFIX "runtime.goroutineheader");
-void	runtime_printtrace(Slice, G*)
-  __asm__ (GOSYM_PREFIX "runtime.printtrace");
 #define runtime_open(p, f, m) open((p), (f), (m))
 #define runtime_read(d, v, n) read((d), (v), (n))
 #define runtime_write(d, v, n) write((d), (v), (n))
@@ -327,8 +312,6 @@
 int32	runtime_callers(int32, Location*, int32, bool keep_callers);
 int64	runtime_nanotime(void)	// monotonic time
   __asm__(GOSYM_PREFIX "runtime.nanotime");
-int64	runtime_unixnanotime(void) // real time, can skip
-  __asm__ (GOSYM_PREFIX "runtime.unixnanotime");
 void	runtime_dopanic(int32) __attribute__ ((noreturn));
 void	runtime_startpanic(void)
   __asm__ (GOSYM_PREFIX "runtime.startpanic");
@@ -343,22 +326,11 @@
 extern int64 runtime_blockprofilerate;
 G*	runtime_netpoll(bool)
   __asm__ (GOSYM_PREFIX "runtime.netpoll");
-void	runtime_crash(void)
-  __asm__ (GOSYM_PREFIX "runtime.crash");
 void	runtime_parsedebugvars(void)
   __asm__(GOSYM_PREFIX "runtime.parsedebugvars");
 void	_rt0_go(void);
 G*	runtime_timejump(void);
 
-void	runtime_callStopTheWorldWithSema(void)
-  __asm__(GOSYM_PREFIX "runtime.callStopTheWorldWithSema");
-void	runtime_callStartTheWorldWithSema(void)
-  __asm__(GOSYM_PREFIX "runtime.callStartTheWorldWithSema");
-void	runtime_acquireWorldsema(void)
-  __asm__(GOSYM_PREFIX "runtime.acquireWorldsema");
-void	runtime_releaseWorldsema(void)
-  __asm__(GOSYM_PREFIX "runtime.releaseWorldsema");
-
 /*
  * mutual exclusion locks.  in the uncontended case,
  * as fast as spin locks (just a few user-level instructions),
@@ -404,17 +376,6 @@
   __asm__ (GOSYM_PREFIX "runtime.notetsleepg");
 
 /*
- * Lock-free stack.
- * Initialize uint64 head to 0, compare with 0 to test for emptiness.
- * The stack does not keep pointers to nodes,
- * so they can be garbage collected if there are no other pointers to nodes.
- */
-void	runtime_lfstackpush(uint64 *head, LFNode *node)
-  __asm__ (GOSYM_PREFIX "runtime.lfstackpush");
-void*	runtime_lfstackpop(uint64 *head)
-  __asm__ (GOSYM_PREFIX "runtime.lfstackpop");
-
-/*
  * low level C-called
  */
 #define runtime_mmap mmap
@@ -454,9 +415,6 @@
 void	runtime_osyield(void)
   __asm__(GOSYM_PREFIX "runtime.osyield");
 
-void	runtime_printcreatedby(G*)
-  __asm__(GOSYM_PREFIX "runtime.printcreatedby");
-
 uintptr	runtime_memlimit(void);
 
 #define ISNAN(f) __builtin_isnan(f)
@@ -491,15 +449,6 @@
 Defer*	runtime_newdefer(void);
 void	runtime_freedefer(Defer*);
 
-struct time_now_ret
-{
-  int64_t sec;
-  int32_t nsec;
-};
-
-struct time_now_ret now() __asm__ (GOSYM_PREFIX "time.now")
-  __attribute__ ((no_split_stack));
-
 extern void _cgo_wait_runtime_init_done (void);
 extern void _cgo_notify_runtime_init_done (void)
   __asm__ (GOSYM_PREFIX "runtime._cgo_notify_runtime_init_done");
diff --git a/libgo/runtime/runtime_c.c b/libgo/runtime/runtime_c.c
index 6da3521..9a6672d 100644
--- a/libgo/runtime/runtime_c.c
+++ b/libgo/runtime/runtime_c.c
@@ -10,6 +10,10 @@
 #include <cpuid.h>
 #endif
 
+#ifdef __linux__
+#include <syscall.h>
+#endif
+
 #include "config.h"
 
 #include "runtime.h"
@@ -81,13 +85,6 @@
 		*(int *)0xf1 = 0xf1;
 }
 
-struct debugVars	runtime_debug;
-
-void
-runtime_setdebug(struct debugVars* d) {
-  runtime_debug = *d;
-}
-
 int32 go_open(char *, int32, int32)
   __asm__ (GOSYM_PREFIX "runtime.open");
 
@@ -184,3 +181,18 @@
 {
   __atomic_thread_fence(__ATOMIC_RELEASE);
 }
+
+#ifdef __linux__
+
+/* Currently sbrk0 is only called on GNU/Linux.  */
+
+uintptr sbrk0(void)
+  __asm__ (GOSYM_PREFIX "runtime.sbrk0");
+
+uintptr
+sbrk0()
+{
+  return syscall(SYS_brk, (uintptr)(0));
+}
+
+#endif /* __linux__ */
diff --git a/libgo/testsuite/gotest b/libgo/testsuite/gotest
index ad3a485..83f78d4 100755
--- a/libgo/testsuite/gotest
+++ b/libgo/testsuite/gotest
@@ -348,18 +348,18 @@
 			fi
 			match=false
 			;;
-		    $goos | $goarch | cgo)
+		    $goos | $goarch | cgo | go1.[0-9])
 			match=true
 			;;
-		    "!"$goos | "!"$goarch | "!cgo")
+		    "!"$goos | "!"$goarch | "!cgo" | "!"go1.[0-9])
 			;;
 		    *,*)
 			cmatch=true
 			for ctag in `echo $tag | sed -e 's/,/ /g'`; do
 			    case $ctag in
-			    $goos | $goarch | cgo)
+			    $goos | $goarch | cgo | go1.[0-9])
 				;;
-			    "!"$goos | "!"$goarch | "!cgo")
+			    "!"$goos | "!"$goarch | "!cgo" | "!"go1.[0-9])
 				cmatch=false
 				;;
 			    "!"*)