cmd/link: convert Link.Filesyms into a slice

Change-Id: I6490de325b0f4ba962c679503102d30d41dcc384
Reviewed-on: https://go-review.googlesource.com/22359
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/link/internal/ld/dwarf.go

@@ -1469,14 +1469,8 @@ func writelines(prev *LSym) *LSym {
 	Adduint8(Ctxt, ls, 1)              // standard_opcode_lengths[9]
 	Adduint8(Ctxt, ls, 0)              // include_directories  (empty)
 
-	files := make([]*LSym, Ctxt.Nhistfile)
-
-	for f := Ctxt.Filesyms; f != nil; f = f.Next {
-		files[f.Value-1] = f
-	}
-
-	for i := 0; int32(i) < Ctxt.Nhistfile; i++ {
-		Addstring(ls, files[i].Name)
+	for _, f := range Ctxt.Filesyms {
+		Addstring(ls, f.Name)
 		Adduint8(Ctxt, ls, 0)
 		Adduint8(Ctxt, ls, 0)
 		Adduint8(Ctxt, ls, 0)

src/cmd/link/internal/ld/link.go

@@ -179,8 +179,7 @@ type Link struct {
 	Cursym     *LSym
 	Version    int
 	Textp      []*LSym
-	Nhistfile  int32
-	Filesyms   *LSym
+	Filesyms   []*LSym
 	Moduledata *LSym
 	LSymBatch  []LSym
 }

src/cmd/link/internal/ld/pcln.go

@@ -147,12 +147,10 @@ func renumberfiles(ctxt *Link, files []*LSym, d *Pcdata) {
 	for i := 0; i < len(files); i++ {
 		f = files[i]
 		if f.Type != obj.SFILEPATH {
-			ctxt.Nhistfile++
-			f.Value = int64(ctxt.Nhistfile)
+			ctxt.Filesyms = append(ctxt.Filesyms, f)
+			f.Value = int64(len(ctxt.Filesyms))
 			f.Type = obj.SFILEPATH
-			f.Next = ctxt.Filesyms
 			f.Name = expandGoroot(f.Name)
-			ctxt.Filesyms = f
 		}
 	}
 
@@ -302,8 +300,8 @@ func pclntab() {
 				// Sanity check the new numbering
 				var it Pciter
 				for pciterinit(Ctxt, &it, &pcln.Pcfile); it.done == 0; pciternext(&it) {
-					if it.value < 1 || it.value > Ctxt.Nhistfile {
-						Diag("bad file number in pcfile: %d not in range [1, %d]\n", it.value, Ctxt.Nhistfile)
+					if it.value < 1 || it.value > int32(len(Ctxt.Filesyms)) {
+						Diag("bad file number in pcfile: %d not in range [1, %d]\n", it.value, len(Ctxt.Filesyms))
 						errorexit()
 					}
 				}
@@ -360,9 +358,10 @@ func pclntab() {
 	pclntabFiletabOffset = start
 	setuint32(Ctxt, ftab, 8+int64(SysArch.PtrSize)+int64(nfunc)*2*int64(SysArch.PtrSize)+int64(SysArch.PtrSize), uint32(start))
 
-	Symgrow(Ctxt, ftab, int64(start)+(int64(Ctxt.Nhistfile)+1)*4)
-	setuint32(Ctxt, ftab, int64(start), uint32(Ctxt.Nhistfile))
-	for s := Ctxt.Filesyms; s != nil; s = s.Next {
+	Symgrow(Ctxt, ftab, int64(start)+(int64(len(Ctxt.Filesyms))+1)*4)
+	setuint32(Ctxt, ftab, int64(start), uint32(len(Ctxt.Filesyms)))
+	for i := len(Ctxt.Filesyms) - 1; i >= 0; i-- {
+		s := Ctxt.Filesyms[i]
 		setuint32(Ctxt, ftab, int64(start)+s.Value*4, uint32(ftabaddstring(ftab, s.Name)))
 	}
 

src/cmd/link/internal/ld/symtab.go

@@ -499,8 +499,8 @@ func symtab() {
 	adduint(Ctxt, moduledata, uint64(pclntabNfunc+1))
 	// The filetab slice
 	Addaddrplus(Ctxt, moduledata, Linklookup(Ctxt, "runtime.pclntab", 0), int64(pclntabFiletabOffset))
-	adduint(Ctxt, moduledata, uint64(Ctxt.Nhistfile)+1)
-	adduint(Ctxt, moduledata, uint64(Ctxt.Nhistfile)+1)
+	adduint(Ctxt, moduledata, uint64(len(Ctxt.Filesyms))+1)
+	adduint(Ctxt, moduledata, uint64(len(Ctxt.Filesyms))+1)
 	// findfunctab
 	Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.findfunctab", 0))
 	// minpc, maxpc