64 bit lsh, sub, and/or/eor. some placeholder files in syscall and os.

R=rsc
APPROVED=rsc
DELTA=204  (139 added, 0 deleted, 65 changed)
OCL=34009
CL=34025
diff --git a/src/cmd/5g/cgen64.c b/src/cmd/5g/cgen64.c
index 9c42a49..05e49fa 100644
--- a/src/cmd/5g/cgen64.c
+++ b/src/cmd/5g/cgen64.c
@@ -98,13 +98,13 @@
 		regfree(&bh);
 		break;
 
-//	case OSUB:
-//		// TODO: Constants.
-//		gins(AMOVL, &lo1, &ax);
-//		gins(AMOVL, &hi1, &dx);
-//		gins(ASUBL, &lo2, &ax);
-//		gins(ASBBL, &hi2, &dx);
-//		break;
+	case OSUB:
+		// TODO: Constants.
+		gins(AMOVW, &lo1, &al);
+		gins(AMOVW, &hi1, &ah);
+		gins(ASUB, &lo2, &al);
+		gins(ASBC, &hi2, &ah);
+		break;
 
 	case OMUL:
 		// TODO(kaib): this can be done with 4 regs and does not need 6
@@ -156,40 +156,53 @@
 
 		break;
 
-//	case OLSH:
-		// TODO(kaib): optimize for OLITERAL
-//		regalloc(&s1, types[TPTR32], N);
-//		regalloc(&s2, types[TPTR32], N);
+	case OLSH:
+		if(r->op == OLITERAL) {
+			v = mpgetfix(r->val.u.xval);
+			if(v >= 64) {
+				// TODO(kaib): replace with gins(AMOVW, nodintconst(0), &al)
+				// here and below (verify it optimizes to EOR)
+				gins(AEOR, &al, &al);
+				gins(AEOR, &ah, &ah);
+				break;
+			}
+			if(v >= 32) {
+				gins(AEOR, &al, &al);
+				//	MOVW	lo1<<(v-32), ah
+				p1 = gins(AMOVW, &lo1, &ah);
+				p1->from.type = D_SHIFT;
+				p1->from.offset = SHIFT_LL | (v-32)<<7 | lo1.val.u.reg;
+				p1->from.reg = NREG;
+				break;
+			}
 
-//		gins(AMOVW, &lo1, &al);
-//		gins(AMOVW, &hi1, &ah);
-//		if(is64(r->type)) {
-//			gins(AMOVW, &lo2, &s1);
-//			gins(AMOVW, &hi2, &s2);
-//			p1 = gins(AOR, &s2, &s1);
-//			p1->from.type = D_SHIFT;
-//			p1->from.offset = 5 << 7 | s2.val.u.reg; // s2<<7
-//			p1->from.reg = NREG;
-//		} else
-//			gins(AMOVW, r, &s1
-//		p1 = gins(AMOVW, &s1, &s2);
-//		p1->from.offset = -32;
+			// general literal left shift
 
-//		//	MOVW	ah<<s1, ah
-//		p1 = gins(AMOVW, &ah, &ah);
-//		p1->from.offset = ah.val.u.reg | 1<<4 | s1.val.u.reg <<8;
+			//	MOVW	lo1<<v, al
+			p1 = gins(AMOVW, &lo1, &al);
+			p1->from.type = D_SHIFT;
+			p1->from.offset = SHIFT_LL | v<<7 | lo1.val.u.reg;
+			p1->from.reg = NREG;
+			break;
 
-		//	OR		al<<s2, ah
-//		p1 = gins(AOR, &al, &ah);
-//		p1->from.offset = al.val.u.reg | 1<<4 | s2.val.u.reg << 8;
+			//	MOVW	hi1<<v, ah
+			p1 = gins(AMOVW, &hi1, &ah);
+			p1->from.type = D_SHIFT;
+			p1->from.offset = SHIFT_LL | v<<7 | hi1.val.u.reg;
+			p1->from.reg = NREG;
+			break;
 
-		//	MOVW	al<<s1, al
-//		p1 = gins(AMOVW, &al, &al);
-//		p1->from.offset = al.val.u.reg | 1<<4 | s1.val.u.reg <<8;
+			//	OR		lo1>>(32-v), ah
+			p1 = gins(AORR, &lo1, &ah);
+			p1->from.type = D_SHIFT;
+			p1->from.offset = SHIFT_LR | (32-v)<<7 | lo1.val.u.reg;
+			p1->from.reg = NREG;
+			break;
+		}
 
-//		regfree(&s1);
-//		regfree(&s2);
-//		break;
+		fatal("cgen64 OLSH, !OLITERAL not implemented");
+		break;
+
 
 	case ORSH:
 		if(r->op == OLITERAL) {
@@ -237,7 +250,7 @@
 				break;
 			}
 
-			// general shift
+			// general literal right shift
 
 			//	MOVW	lo1>>v, al
 			p1 = gins(AMOVW, &lo1, &al);
@@ -319,10 +332,11 @@
 //		patch(p2, pc);
 //		break;
 
-//	case OXOR:
-//	case OAND:
-//	case OOR:
-//		// make constant the right side (it usually is anyway).
+	case OXOR:
+	case OAND:
+	case OOR:
+		// TODO(kaib): literal optimizations
+		// make constant the right side (it usually is anyway).
 //		if(lo1.op == OLITERAL) {
 //			nswap(&lo1, &lo2);
 //			nswap(&hi1, &hi2);
@@ -413,11 +427,11 @@
 //			splitclean();
 //			goto out;
 //		}
-//		gins(AMOVL, &lo1, &ax);
-//		gins(AMOVL, &hi1, &dx);
-//		gins(optoas(n->op, lo1.type), &lo2, &ax);
-//		gins(optoas(n->op, lo1.type), &hi2, &dx);
-//		break;
+		gins(AMOVW, &lo1, &al);
+		gins(AMOVW, &hi1, &ah);
+		gins(optoas(n->op, lo1.type), &lo2, &al);
+		gins(optoas(n->op, lo1.type), &hi2, &ah);
+		break;
 	}
 	if(is64(r->type))
 		splitclean();
diff --git a/src/pkg/os/dir_linux_arm.go b/src/pkg/os/dir_linux_arm.go
new file mode 100644
index 0000000..0e70f0b
--- /dev/null
+++ b/src/pkg/os/dir_linux_arm.go
@@ -0,0 +1,81 @@
+// 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.
+
+// TODO(rsc): Once the porting dust settles, consider
+// whether this file should be dir_linux.go (and similarly
+// dir_darwin.go) instead of having one copy per architecture.
+
+package os
+
+import (
+	"syscall";
+	"unsafe";
+)
+
+const (
+	blockSize = 4096	// TODO(r): use statfs
+)
+
+func clen(n []byte) int {
+	for i := 0; i < len(n); i++ {
+		if n[i] == 0 {
+			return i
+		}
+	}
+	return len(n)
+}
+
+func (file *File) Readdirnames(count int) (names []string, err Error) {
+	// If this file has no dirinfo, create one.
+	if file.dirinfo == nil {
+		file.dirinfo = new(dirInfo);
+		// The buffer must be at least a block long.
+		// TODO(r): use fstatfs to find fs block size.
+		file.dirinfo.buf = make([]byte, blockSize);
+	}
+	d := file.dirinfo;
+	size := count;
+	if size < 0 {
+		size = 100
+	}
+	names = make([]string, 0, size);	// Empty with room to grow.
+	for count != 0 {
+		// Refill the buffer if necessary
+		if d.bufp >= d.nbuf {
+			var errno int;
+			d.nbuf, errno = syscall.Getdents(file.fd, d.buf);
+			if errno != 0 {
+				return names, NewSyscallError("getdents", errno)
+			}
+			if d.nbuf <= 0 {
+				break	// EOF
+			}
+			d.bufp = 0;
+		}
+		// Drain the buffer
+		for count != 0 && d.bufp < d.nbuf {
+			dirent := (*syscall.Dirent)(unsafe.Pointer(&d.buf[d.bufp]));
+			d.bufp += int(dirent.Reclen);
+			if dirent.Ino == 0 {	// File absent in directory.
+				continue
+			}
+			bytes := (*[len(dirent.Name)]byte)(unsafe.Pointer(&dirent.Name[0]));
+			var name = string(bytes[0:clen(bytes)]);
+			if name == "." || name == ".." {	// Useless names
+				continue
+			}
+			count--;
+			if len(names) == cap(names) {
+				nnames := make([]string, len(names), 2*len(names));
+				for i := 0; i < len(names); i++ {
+					nnames[i] = names[i]
+				}
+				names = nnames;
+			}
+			names = names[0:len(names)+1];
+			names[len(names)-1] = name;
+		}
+	}
+	return names, nil;
+}
diff --git a/src/pkg/os/stat_linux_arm.go b/src/pkg/os/stat_linux_arm.go
new file mode 100644
index 0000000..d08fabc
--- /dev/null
+++ b/src/pkg/os/stat_linux_arm.go
@@ -0,0 +1,44 @@
+// 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.
+
+// TODO(rsc): Once the porting dust settles, consider
+// whether this file should be stat_linux.go (and similarly
+// stat_darwin.go) instead of having one copy per architecture.
+
+// 386, Linux
+
+package os
+
+import "syscall"
+
+func isSymlink(stat *syscall.Stat_t) bool {
+	return stat.Mode & syscall.S_IFMT == syscall.S_IFLNK
+}
+
+func dirFromStat(name string, dir *Dir, lstat, stat *syscall.Stat_t) *Dir {
+	dir.Dev = stat.Dev;
+	dir.Ino = uint64(stat.Ino);
+	dir.Nlink = uint64(stat.Nlink);
+	dir.Mode = stat.Mode;
+	dir.Uid = stat.Uid;
+	dir.Gid = stat.Gid;
+	dir.Rdev = stat.Rdev;
+	dir.Size = uint64(stat.Size);
+	dir.Blksize = uint64(stat.Blksize);
+	dir.Blocks = uint64(stat.Blocks);
+	dir.Atime_ns = uint64(syscall.TimespecToNsec(stat.Atim));
+	dir.Mtime_ns = uint64(syscall.TimespecToNsec(stat.Mtim));
+	dir.Ctime_ns = uint64(syscall.TimespecToNsec(stat.Ctim));
+	for i := len(name) - 1; i >= 0; i-- {
+		if name[i] == '/' {
+			name = name[i+1:len(name)];
+			break;
+		}
+	}
+	dir.Name = name;
+	if isSymlink(lstat) && !isSymlink(stat) {
+		dir.FollowedSymlink = true;
+	}
+	return dir;
+}
diff --git a/src/pkg/syscall/asm_linux_arm.s b/src/pkg/syscall/asm_linux_arm.s
new file mode 100644
index 0000000..024018d
--- /dev/null
+++ b/src/pkg/syscall/asm_linux_arm.s
@@ -0,0 +1,4 @@
+// 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.
+
diff --git a/src/pkg/syscall/ztypes_linux_arm.go b/src/pkg/syscall/ztypes_linux_arm.go
index a3b1e6b..c038e02 100644
--- a/src/pkg/syscall/ztypes_linux_arm.go
+++ b/src/pkg/syscall/ztypes_linux_arm.go
@@ -1,4 +1,4 @@
-// godefs -gsyscall -f-m32 types_linux.c types_linux_386.c
+// godefs -gsyscall -f-m32 types_linux.c
 
 // MACHINE GENERATED - DO NOT EDIT.
 
@@ -163,18 +163,18 @@
 	Calcnt int32;
 	Errcnt int32;
 	Stbcnt int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
-	 int32;
+	Pad0 int32;
+	Pad1 int32;
+	Pad2 int32;
+	Pad3 int32;
+	Pad4 int32;
+	Pad5 int32;
+	Pad6 int32;
+	Pad7 int32;
+	Pad8 int32;
+	Pad9 int32;
+	Pad10 int32;
+	Pad11 int32;
 }
 
 type Time_t int32
@@ -314,7 +314,7 @@
 	__fs uint16;
 	Gs uint16;
 	__gs uint16;
-	Eax int32;
+	Orig_eax int32;
 	Eip int32;
 	Cs uint16;
 	__cs uint16;