cmd/internal/gc: remove namebuf variable
namebuf was a global char buffer in the C version of gc, which was
useful for providing common storage for constructing symbol and file
names. However, now that it's just a global Go string and the string
data is dynamically allocated anyway, it doesn't serve any purpose
except to force extra write barriers everytime it's assigned to.
Also, introduce Lookupf(fmt, args...) as shorthand for
Lookup(fmt.Sprintf(fmt, args...)), which was a very common pattern for
using namebuf.
Passes "go build -toolexec 'toolstash -cmp' -a std".
Notably, this CL shrinks 6g's text section by ~15kB:
$ size toolstash/6g tool/linux_amd64/6g
text data bss dec hex filename
4600805 605968 342988 5549761 54aec1 toolstash/6g
4585547 605968 342956 5534471 547307 tool/linux_amd64/6g
Change-Id: I98abb44fc7f43a2e2e48425cc9f215cd0be37442
Reviewed-on: https://go-review.googlesource.com/7080
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/cmd/internal/gc/closure.go b/src/cmd/internal/gc/closure.go
index 3155b69..df89544 100644
--- a/src/cmd/internal/gc/closure.go
+++ b/src/cmd/internal/gc/closure.go
@@ -174,8 +174,7 @@
} else {
Fatal("closurename called for %v", Nconv(n, obj.FmtShort))
}
- namebuf = fmt.Sprintf("%s.%s%d", outer, prefix, gen)
- n.Sym = Lookup(namebuf)
+ n.Sym = Lookupf("%s.%s%d", outer, prefix, gen)
return n.Sym
}
@@ -333,9 +332,7 @@
// we introduce function param &v *T
// and v remains PPARAMREF with &v heapaddr
// (accesses will implicitly deref &v).
- namebuf = fmt.Sprintf("&%s", v.Sym.Name)
-
- addr = newname(Lookup(namebuf))
+ addr = newname(Lookupf("&%s", v.Sym.Name))
addr.Type = Ptrto(v.Type)
addr.Class = PPARAM
v.Heapaddr = addr
@@ -397,9 +394,7 @@
} else {
// Declare variable holding addresses taken from closure
// and initialize in entry prologue.
- namebuf = fmt.Sprintf("&%s", v.Sym.Name)
-
- addr = newname(Lookup(namebuf))
+ addr = newname(Lookupf("&%s", v.Sym.Name))
addr.Ntype = Nod(OIND, typenod(v.Type), nil)
addr.Class = PAUTO
addr.Used = true
@@ -557,9 +552,8 @@
var fld *Node
var n *Node
for t := getinargx(t0).Type; t != nil; t = t.Down {
- namebuf = fmt.Sprintf("a%d", i)
+ n = newname(Lookupf("a%d", i))
i++
- n = newname(Lookup(namebuf))
n.Class = PPARAM
xfunc.Dcl = list(xfunc.Dcl, n)
callargs = list(callargs, n)
@@ -577,9 +571,8 @@
l = nil
var retargs *NodeList
for t := getoutargx(t0).Type; t != nil; t = t.Down {
- namebuf = fmt.Sprintf("r%d", i)
+ n = newname(Lookupf("r%d", i))
i++
- n = newname(Lookup(namebuf))
n.Class = PPARAMOUT
xfunc.Dcl = list(xfunc.Dcl, n)
retargs = list(retargs, n)
diff --git a/src/cmd/internal/gc/dcl.go b/src/cmd/internal/gc/dcl.go
index 7194c12..fa955ba 100644
--- a/src/cmd/internal/gc/dcl.go
+++ b/src/cmd/internal/gc/dcl.go
@@ -645,10 +645,8 @@
if n.Left == nil {
// Name so that escape analysis can track it. ~r stands for 'result'.
- namebuf = fmt.Sprintf("~r%d", gen)
+ n.Left = newname(Lookupf("~r%d", gen))
gen++
-
- n.Left = newname(Lookup(namebuf))
}
// TODO: n->left->missing = 1;
@@ -667,9 +665,8 @@
*nn = *n.Left
nn.Orig = nn
- namebuf = fmt.Sprintf("~b%d", gen)
+ nn.Sym = Lookupf("~b%d", gen)
gen++
- nn.Sym = Lookup(namebuf)
n.Left = nn
}
diff --git a/src/cmd/internal/gc/gen.go b/src/cmd/internal/gc/gen.go
index 70c218e..3777cc3 100644
--- a/src/cmd/internal/gc/gen.go
+++ b/src/cmd/internal/gc/gen.go
@@ -590,10 +590,8 @@
// give each tmp a different name so that there
// a chance to registerizer them
- namebuf = fmt.Sprintf("autotmp_%.4d", statuniqgen)
-
+ s := Lookupf("autotmp_%.4d", statuniqgen)
statuniqgen++
- s := Lookup(namebuf)
n := Nod(ONAME, nil, nil)
n.Sym = s
s.Def = n
diff --git a/src/cmd/internal/gc/go.go b/src/cmd/internal/gc/go.go
index 348dd83..e9412d1 100644
--- a/src/cmd/internal/gc/go.go
+++ b/src/cmd/internal/gc/go.go
@@ -500,8 +500,6 @@
var nolocalimports int
-var namebuf string
-
var lexbuf bytes.Buffer
var strbuf bytes.Buffer
diff --git a/src/cmd/internal/gc/init.go b/src/cmd/internal/gc/init.go
index c57e50b..8aaed8c 100644
--- a/src/cmd/internal/gc/init.go
+++ b/src/cmd/internal/gc/init.go
@@ -4,8 +4,6 @@
package gc
-import "fmt"
-
// case OADD:
// if(n->right->op == OLITERAL) {
// v = n->right->vconst;
@@ -31,8 +29,7 @@
func renameinit() *Sym {
renameinit_initgen++
- namebuf = fmt.Sprintf("init.%d", renameinit_initgen)
- return Lookup(namebuf)
+ return Lookupf("init.%d", renameinit_initgen)
}
/*
@@ -112,18 +109,14 @@
var r *NodeList
// (1)
- namebuf = "initdone·"
-
- gatevar := newname(Lookup(namebuf))
+ gatevar := newname(Lookup("initdone·"))
addvar(gatevar, Types[TUINT8], PEXTERN)
// (2)
Maxarg = 0
- namebuf = "init"
-
fn := Nod(ODCLFUNC, nil, nil)
- initsym := Lookup(namebuf)
+ initsym := Lookup("init")
fn.Nname = newname(initsym)
fn.Nname.Defn = fn
fn.Nname.Ntype = Nod(OTFUNC, nil, nil)
@@ -169,8 +162,7 @@
// (9)
// could check that it is fn of no args/returns
for i := 1; ; i++ {
- namebuf = fmt.Sprintf("init.%d", i)
- s := Lookup(namebuf)
+ s := Lookupf("init.%d", i)
if s.Def == nil {
break
}
diff --git a/src/cmd/internal/gc/inl.go b/src/cmd/internal/gc/inl.go
index c266f7d..cdd709e 100644
--- a/src/cmd/internal/gc/inl.go
+++ b/src/cmd/internal/gc/inl.go
@@ -859,8 +859,7 @@
// Synthesize a variable to store the inlined function's results in.
func retvar(t *Type, i int) *Node {
- namebuf = fmt.Sprintf("~r%d", i)
- n := newname(Lookup(namebuf))
+ n := newname(Lookupf("~r%d", i))
n.Type = t.Type
n.Class = PAUTO
n.Used = true
@@ -872,8 +871,7 @@
// Synthesize a variable to store the inlined function's arguments
// when they come from a multiple return call.
func argvar(t *Type, i int) *Node {
- namebuf = fmt.Sprintf("~arg%d", i)
- n := newname(Lookup(namebuf))
+ n := newname(Lookupf("~arg%d", i))
n.Type = t.Type
n.Class = PAUTO
n.Used = true
@@ -886,8 +884,7 @@
func newlabel_inl() *Node {
newlabel_inl_label++
- namebuf = fmt.Sprintf(".inlret%.6d", newlabel_inl_label)
- n := newname(Lookup(namebuf))
+ n := newname(Lookupf(".inlret%.6d", newlabel_inl_label))
n.Etype = 1 // flag 'safe' for escape analysis (no backjumps)
return n
}
diff --git a/src/cmd/internal/gc/lex.go b/src/cmd/internal/gc/lex.go
index 816e67e..03e8749 100644
--- a/src/cmd/internal/gc/lex.go
+++ b/src/cmd/internal/gc/lex.go
@@ -559,25 +559,24 @@
strings.HasPrefix(name, "../") || name == ".."
}
-func findpkg(name string) bool {
+func findpkg(name string) (file string, ok bool) {
if islocalname(name) {
if safemode != 0 || nolocalimports != 0 {
- return false
+ return "", false
}
// try .a before .6. important for building libraries:
// if there is an array.6 in the array.a library,
// want to find all of array.a, not just array.6.
- namebuf = fmt.Sprintf("%s.a", name)
-
- if obj.Access(namebuf, 0) >= 0 {
- return true
+ file = fmt.Sprintf("%s.a", name)
+ if obj.Access(file, 0) >= 0 {
+ return file, true
}
- namebuf = fmt.Sprintf("%s.%c", name, Thearch.Thechar)
- if obj.Access(namebuf, 0) >= 0 {
- return true
+ file = fmt.Sprintf("%s.%c", name, Thearch.Thechar)
+ if obj.Access(file, 0) >= 0 {
+ return file, true
}
- return false
+ return "", false
}
// local imports should be canonicalized already.
@@ -587,17 +586,17 @@
_ = q
if path.Clean(name) != name {
Yyerror("non-canonical import path %q (should be %q)", name, q)
- return false
+ return "", false
}
for p := idirs; p != nil; p = p.link {
- namebuf = fmt.Sprintf("%s/%s.a", p.dir, name)
- if obj.Access(namebuf, 0) >= 0 {
- return true
+ file = fmt.Sprintf("%s/%s.a", p.dir, name)
+ if obj.Access(file, 0) >= 0 {
+ return file, true
}
- namebuf = fmt.Sprintf("%s/%s.%c", p.dir, name, Thearch.Thechar)
- if obj.Access(namebuf, 0) >= 0 {
- return true
+ file = fmt.Sprintf("%s/%s.%c", p.dir, name, Thearch.Thechar)
+ if obj.Access(file, 0) >= 0 {
+ return file, true
}
}
@@ -612,17 +611,17 @@
suffix = "race"
}
- namebuf = fmt.Sprintf("%s/pkg/%s_%s%s%s/%s.a", goroot, goos, goarch, suffixsep, suffix, name)
- if obj.Access(namebuf, 0) >= 0 {
- return true
+ file = fmt.Sprintf("%s/pkg/%s_%s%s%s/%s.a", goroot, goos, goarch, suffixsep, suffix, name)
+ if obj.Access(file, 0) >= 0 {
+ return file, true
}
- namebuf = fmt.Sprintf("%s/pkg/%s_%s%s%s/%s.%c", goroot, goos, goarch, suffixsep, suffix, name, Thearch.Thechar)
- if obj.Access(namebuf, 0) >= 0 {
- return true
+ file = fmt.Sprintf("%s/pkg/%s_%s%s%s/%s.%c", goroot, goos, goarch, suffixsep, suffix, name, Thearch.Thechar)
+ if obj.Access(file, 0) >= 0 {
+ return file, true
}
}
- return false
+ return "", false
}
func fakeimport() {
@@ -698,7 +697,8 @@
}
}
- if !findpkg(path_) {
+ file, found := findpkg(path_)
+ if !found {
Yyerror("can't find import: %q", f.U.Sval)
errorexit()
}
@@ -708,7 +708,6 @@
// If we already saw that package, feed a dummy statement
// to the lexer to avoid parsing export data twice.
if importpkg.Imported != 0 {
- file := namebuf
tag := ""
if importpkg.Safe {
tag = "safe"
@@ -723,16 +722,13 @@
var err error
var imp *obj.Biobuf
- imp, err = obj.Bopenr(namebuf)
+ imp, err = obj.Bopenr(file)
if err != nil {
Yyerror("can't open import: %q: %v", f.U.Sval, err)
errorexit()
}
- file := namebuf
-
- n := len(namebuf)
- if n > 2 && namebuf[n-2] == '.' && namebuf[n-1] == 'a' {
+ if strings.HasSuffix(file, ".a") {
if !skiptopkgdef(imp) {
Yyerror("import %s: not a package file", file)
errorexit()
@@ -757,7 +753,7 @@
// assume files move (get installed)
// so don't record the full path.
- linehist(file[n-len(path_)-2:], -1, 1) // acts as #pragma lib
+ linehist(file[len(file)-len(path_)-2:], -1, 1) // acts as #pragma lib
/*
* position the input right
@@ -3162,10 +3158,9 @@
p = p[i+1:]
}
}
- namebuf = p
- if i := strings.LastIndex(namebuf, "."); i >= 0 {
- namebuf = namebuf[:i]
+ if i := strings.LastIndex(p, "."); i >= 0 {
+ p = p[:i]
}
- outfile = fmt.Sprintf("%s.%c", namebuf, Thearch.Thechar)
+ outfile = fmt.Sprintf("%s.%c", p, Thearch.Thechar)
}
}
diff --git a/src/cmd/internal/gc/obj.go b/src/cmd/internal/gc/obj.go
index d59898f..077b89b 100644
--- a/src/cmd/internal/gc/obj.go
+++ b/src/cmd/internal/gc/obj.go
@@ -101,8 +101,8 @@
obj.Bputc(bout, 0)
}
obj.Bseek(bout, startobj-ArhdrSize, 0)
- namebuf = fmt.Sprintf("_go_.%c", Thearch.Thechar)
- formathdr(arhdr[:], namebuf, size)
+ name := fmt.Sprintf("_go_.%c", Thearch.Thechar)
+ formathdr(arhdr[:], name, size)
obj.Bwrite(bout, arhdr[:])
}
@@ -199,22 +199,23 @@
var stringsym_gen int
func stringsym(s string) *Sym {
+ var symname string
var pkg *Pkg
if len(s) > 100 {
// huge strings are made static to avoid long names
stringsym_gen++
- namebuf = fmt.Sprintf(".gostring.%d", stringsym_gen)
+ symname = fmt.Sprintf(".gostring.%d", stringsym_gen)
pkg = localpkg
} else {
// small strings get named by their contents,
// so that multiple modules using the same string
// can share it.
- namebuf = fmt.Sprintf("%q", s)
+ symname = fmt.Sprintf("%q", s)
pkg = gostringpkg
}
- sym := Pkglookup(namebuf, pkg)
+ sym := Pkglookup(symname, pkg)
// SymUniq flag indicates that data is generated already
if sym.Flags&SymUniq != 0 {
@@ -252,8 +253,8 @@
var m int
slicebytes_gen++
- namebuf = fmt.Sprintf(".gobytes.%d", slicebytes_gen)
- sym := Pkglookup(namebuf, localpkg)
+ symname := fmt.Sprintf(".gobytes.%d", slicebytes_gen)
+ sym := Pkglookup(symname, localpkg)
sym.Def = newname(sym)
off := 0
diff --git a/src/cmd/internal/gc/pgen.go b/src/cmd/internal/gc/pgen.go
index 208ecb8..0623904 100644
--- a/src/cmd/internal/gc/pgen.go
+++ b/src/cmd/internal/gc/pgen.go
@@ -18,9 +18,8 @@
func makefuncdatasym(namefmt string, funcdatakind int64) *Sym {
var nod Node
- namebuf = fmt.Sprintf(namefmt, makefuncdatasym_nsym)
+ sym := Lookupf(namefmt, makefuncdatasym_nsym)
makefuncdatasym_nsym++
- sym := Lookup(namebuf)
pnod := newname(sym)
pnod.Class = PEXTERN
Nodconst(&nod, Types[TINT32], funcdatakind)
diff --git a/src/cmd/internal/gc/sinit.go b/src/cmd/internal/gc/sinit.go
index c5e006b..2dec757 100644
--- a/src/cmd/internal/gc/sinit.go
+++ b/src/cmd/internal/gc/sinit.go
@@ -517,9 +517,8 @@
* part of the composite literal.
*/
func staticname(t *Type, ctxt int) *Node {
- namebuf = fmt.Sprintf("statictmp_%.4d", statuniqgen)
+ n := newname(Lookupf("statictmp_%.4d", statuniqgen))
statuniqgen++
- n := newname(Lookup(namebuf))
if ctxt == 0 {
n.Readonly = true
}
diff --git a/src/cmd/internal/gc/subr.go b/src/cmd/internal/gc/subr.go
index c59b7e6..f77d151 100644
--- a/src/cmd/internal/gc/subr.go
+++ b/src/cmd/internal/gc/subr.go
@@ -281,6 +281,10 @@
return localpkg.Lookup(name)
}
+func Lookupf(format string, a ...interface{}) *Sym {
+ return Lookup(fmt.Sprintf(format, a...))
+}
+
func LookupBytes(name []byte) *Sym {
return localpkg.LookupBytes(name)
}
diff --git a/src/cmd/internal/gc/walk.go b/src/cmd/internal/gc/walk.go
index e88b4c2..e4abc28 100644
--- a/src/cmd/internal/gc/walk.go
+++ b/src/cmd/internal/gc/walk.go
@@ -1109,17 +1109,18 @@
if Widthreg >= 8 || (et != TUINT64 && et != TINT64) {
goto ret
}
+ var fn string
if et == TINT64 {
- namebuf = "int64"
+ fn = "int64"
} else {
- namebuf = "uint64"
+ fn = "uint64"
}
if n.Op == ODIV {
- namebuf += "div"
+ fn += "div"
} else {
- namebuf += "mod"
+ fn += "mod"
}
- n = mkcall(namebuf, n.Type, init, conv(n.Left, Types[et]), conv(n.Right, Types[et]))
+ n = mkcall(fn, n.Type, init, conv(n.Left, Types[et]), conv(n.Right, Types[et]))
default:
break
@@ -2882,13 +2883,14 @@
args = list(args, conv(l.N, Types[TSTRING]))
}
+ var fn string
if c <= 5 {
// small numbers of strings use direct runtime helpers.
// note: orderexpr knows this cutoff too.
- namebuf = fmt.Sprintf("concatstring%d", c)
+ fn = fmt.Sprintf("concatstring%d", c)
} else {
// large numbers of strings are passed to the runtime as a slice.
- namebuf = "concatstrings"
+ fn = "concatstrings"
t := typ(TARRAY)
t.Type = Types[TSTRING]
@@ -2901,7 +2903,7 @@
slice.Esc = EscNone
}
- cat := syslook(namebuf, 1)
+ cat := syslook(fn, 1)
r := Nod(OCALL, cat, nil)
r.List = args
typecheck(&r, Erv)
