From 382b44eb7c4357cd17be403addfd0ca46bfa2e79 Mon Sep 17 00:00:00 2001 From: Russ Cox Date: Mon, 23 Feb 2015 16:07:24 -0500 Subject: [dev.cc] cmd/5g etc: code cleanup: delay var decls and eliminate dead code Ran rsc.io/grind rev 6f0e601 on the source files. The cleanups move var declarations as close to the use as possible, splitting disjoint uses of the var into separate variables. They also remove dead code (especially in func sudoaddable), which helps with the var moving. There's more cleanup to come, but this alone cuts the time spent compiling html/template on my 2013 MacBook Pro from 3.1 seconds to 2.3 seconds. Change-Id: I4de499f47b1dd47a560c310bbcde6b08d425cfd6 Reviewed-on: https://go-review.googlesource.com/5637 Reviewed-by: Rob Pike --- src/cmd/internal/obj/objfile.go | 76 +++++++++++++++++------------------------ 1 file changed, 31 insertions(+), 45 deletions(-) (limited to 'src/cmd/internal/obj/objfile.go') diff --git a/src/cmd/internal/obj/objfile.go b/src/cmd/internal/obj/objfile.go index b15bd007af..6e76a39c53 100644 --- a/src/cmd/internal/obj/objfile.go +++ b/src/cmd/internal/obj/objfile.go @@ -18,15 +18,7 @@ var outfile string // does not write out object files. func Writeobjdirect(ctxt *Link, b *Biobuf) { var flag int - var found int - var h *Hist var s *LSym - var text *LSym - var etext *LSym - var curtext *LSym - var data *LSym - var edata *LSym - var pl *Plist var p *Prog var plink *Prog var a *Auto @@ -34,13 +26,13 @@ func Writeobjdirect(ctxt *Link, b *Biobuf) { // Build list of symbols, and assign instructions to lists. // Ignore ctxt->plist boundaries. There are no guarantees there, // and the C compilers and assemblers just use one big list. - text = nil + text := (*LSym)(nil) - curtext = nil - data = nil - etext = nil - edata = nil - for pl = ctxt.Plist; pl != nil; pl = pl.Link { + curtext := (*LSym)(nil) + data := (*LSym)(nil) + etext := (*LSym)(nil) + edata := (*LSym)(nil) + for pl := ctxt.Plist; pl != nil; pl = pl.Link { for p = pl.Firstpc; p != nil; p = plink { if ctxt.Debugasm != 0 && ctxt.Debugvlog != 0 { fmt.Printf("obj: %v\n", p) @@ -176,7 +168,8 @@ func Writeobjdirect(ctxt *Link, b *Biobuf) { } // Add reference to Go arguments for C or assembly functions without them. - for s = text; s != nil; s = s.Next { + var found int + for s := text; s != nil; s = s.Next { if !strings.HasPrefix(s.Name, "\"\".") { continue } @@ -200,7 +193,7 @@ func Writeobjdirect(ctxt *Link, b *Biobuf) { } // Turn functions into machine code images. - for s = text; s != nil; s = s.Next { + for s := text; s != nil; s = s.Next { mkfwd(s) linkpatch(ctxt, s) ctxt.Arch.Follow(ctxt, s) @@ -217,7 +210,7 @@ func Writeobjdirect(ctxt *Link, b *Biobuf) { Bputc(b, 1) // version // Emit autolib. - for h = ctxt.Hist; h != nil; h = h.Link { + for h := ctxt.Hist; h != nil; h = h.Link { if h.Offset < 0 { wrstring(b, h.Name) } @@ -225,10 +218,10 @@ func Writeobjdirect(ctxt *Link, b *Biobuf) { wrstring(b, "") // Emit symbols. - for s = text; s != nil; s = s.Next { + for s := text; s != nil; s = s.Next { writesym(ctxt, b, s) } - for s = data; s != nil; s = s.Next { + for s := data; s != nil; s = s.Next { writesym(ctxt, b, s) } @@ -240,16 +233,6 @@ func Writeobjdirect(ctxt *Link, b *Biobuf) { } func writesym(ctxt *Link, b *Biobuf, s *LSym) { - var r *Reloc - var i int - var j int - var c int - var n int - var pc *Pcln - var p *Prog - var a *Auto - var name string - if ctxt.Debugasm != 0 { fmt.Fprintf(ctxt.Bso, "%s ", s.Name) if s.Version != 0 { @@ -276,10 +259,12 @@ func writesym(ctxt *Link, b *Biobuf, s *LSym) { } fmt.Fprintf(ctxt.Bso, "\n") - for p = s.Text; p != nil; p = p.Link { + for p := s.Text; p != nil; p = p.Link { fmt.Fprintf(ctxt.Bso, "\t%#04x %v\n", uint(int(p.Pc)), p) } - for i = 0; i < len(s.P); { + var c int + var j int + for i := 0; i < len(s.P); { fmt.Fprintf(ctxt.Bso, "\t%#04x", uint(i)) for j = i; j < i+16 && j < len(s.P); j++ { fmt.Fprintf(ctxt.Bso, " %02x", s.P[j]) @@ -301,7 +286,9 @@ func writesym(ctxt *Link, b *Biobuf, s *LSym) { i += 16 } - for i = 0; i < len(s.R); i++ { + var r *Reloc + var name string + for i := 0; i < len(s.R); i++ { r = &s.R[i] name = "" if r.Sym != nil { @@ -325,7 +312,8 @@ func writesym(ctxt *Link, b *Biobuf, s *LSym) { wrdata(b, s.P) wrint(b, int64(len(s.R))) - for i = 0; i < len(s.R); i++ { + var r *Reloc + for i := 0; i < len(s.R); i++ { r = &s.R[i] wrint(b, int64(r.Off)) wrint(b, int64(r.Siz)) @@ -341,12 +329,12 @@ func writesym(ctxt *Link, b *Biobuf, s *LSym) { wrint(b, int64(s.Locals)) wrint(b, int64(s.Nosplit)) wrint(b, int64(s.Leaf)|int64(s.Cfunc)<<1) - n = 0 - for a = s.Autom; a != nil; a = a.Link { + n := 0 + for a := s.Autom; a != nil; a = a.Link { n++ } wrint(b, int64(n)) - for a = s.Autom; a != nil; a = a.Link { + for a := s.Autom; a != nil; a = a.Link { wrsym(b, a.Asym) wrint(b, int64(a.Aoffset)) if a.Name == NAME_AUTO { @@ -359,35 +347,33 @@ func writesym(ctxt *Link, b *Biobuf, s *LSym) { wrsym(b, a.Gotype) } - pc = s.Pcln + pc := s.Pcln wrdata(b, pc.Pcsp.P) wrdata(b, pc.Pcfile.P) wrdata(b, pc.Pcline.P) wrint(b, int64(len(pc.Pcdata))) - for i = 0; i < len(pc.Pcdata); i++ { + for i := 0; i < len(pc.Pcdata); i++ { wrdata(b, pc.Pcdata[i].P) } wrint(b, int64(len(pc.Funcdataoff))) - for i = 0; i < len(pc.Funcdataoff); i++ { + for i := 0; i < len(pc.Funcdataoff); i++ { wrsym(b, pc.Funcdata[i]) } - for i = 0; i < len(pc.Funcdataoff); i++ { + for i := 0; i < len(pc.Funcdataoff); i++ { wrint(b, pc.Funcdataoff[i]) } wrint(b, int64(len(pc.File))) - for i = 0; i < len(pc.File); i++ { + for i := 0; i < len(pc.File); i++ { wrpathsym(ctxt, b, pc.File[i]) } } } func wrint(b *Biobuf, sval int64) { - var uv uint64 var v uint64 var buf [10]uint8 - var p []uint8 - uv = (uint64(sval) << 1) ^ uint64(int64(sval>>63)) - p = buf[:] + uv := (uint64(sval) << 1) ^ uint64(int64(sval>>63)) + p := buf[:] for v = uv; v >= 0x80; v >>= 7 { p[0] = uint8(v | 0x80) p = p[1:] -- cgit v1.3