[dev.link] cmd/link: remove elf sym fields from sym.Symbol

Remove the "ElfSym" and "LocalElfSym" fields from sym.Symbol,
replacing uses with loader method calls as needed.

Change-Id: I3828f13203ece2bdc03eeb09ab37a5c94e21a726
Reviewed-on: https://go-review.googlesource.com/c/go/+/230462
Reviewed-by: Cherry Zhang <cherryyz@google.com>

src/cmd/link/internal/amd64/asm.go

@@ -396,7 +396,7 @@ func adddynrel2(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s load
 func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 	ctxt.Out.Write64(uint64(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	switch r.Type {
 	default:
 		return false

src/cmd/link/internal/arm/asm.go

@@ -252,7 +252,7 @@ func adddynrel2(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s load
 func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 	ctxt.Out.Write32(uint32(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	switch r.Type {
 	default:
 		return false

src/cmd/link/internal/arm64/asm.go

@@ -328,7 +328,7 @@ func adddynrel2(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s load
 func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 	ctxt.Out.Write64(uint64(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	switch r.Type {
 	default:
 		return false

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

@@ -1411,7 +1411,8 @@ func elfrelocsect(ctxt *Link, sect *sym.Section, syms []*sym.Symbol) {
 				Errorf(s, "missing xsym in relocation %#v %#v", r.Sym.Name, s)
 				continue
 			}
-			if r.Xsym.ElfsymForReloc() == 0 {
+			esr := ElfSymForReloc(ctxt, r.Xsym)
+			if esr == 0 {
 				Errorf(s, "reloc %d (%s) to non-elf symbol %s (outer=%s) %d (%s)", r.Type, sym.RelocName(ctxt.Arch, r.Type), r.Sym.Name, r.Xsym.Name, r.Sym.Type, r.Sym.Type)
 			}
 			if !r.Xsym.Attr.Reachable() {

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

@@ -2918,6 +2918,17 @@ func symPkg(ctxt *Link, s *sym.Symbol) string {
 	return ctxt.loader.SymPkg(loader.Sym(s.SymIdx))
 }
 
+func ElfSymForReloc(ctxt *Link, s *sym.Symbol) int32 {
+	// If putelfsym created a local version of this symbol, use that in all
+	// relocations.
+	les := ctxt.loader.SymLocalElfSym(loader.Sym(s.SymIdx))
+	if les != 0 {
+		return les
+	} else {
+		return ctxt.loader.SymElfSym(loader.Sym(s.SymIdx))
+	}
+}
+
 func (ctxt *Link) dumpsyms() {
 	for _, s := range ctxt.loader.Syms {
 		if s == nil {

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

@@ -185,7 +185,7 @@ func putelfsym(ctxt *Link, x *sym.Symbol, s string, t SymbolType, addr int64) {
 		// ELF linker -Bsymbolic-functions option, but that is buggy on
 		// several platforms.
 		putelfsyment(ctxt.Out, putelfstr("local."+s), addr, size, STB_LOCAL<<4|typ&0xf, elfshnum, other)
-		x.LocalElfsym = int32(ctxt.numelfsym)
+		ctxt.loader.SetSymLocalElfSym(loader.Sym(x.SymIdx), int32(ctxt.numelfsym))
 		ctxt.numelfsym++
 		return
 	} else if bind != ctxt.elfbind {
@@ -193,13 +193,13 @@ func putelfsym(ctxt *Link, x *sym.Symbol, s string, t SymbolType, addr int64) {
 	}
 
 	putelfsyment(ctxt.Out, putelfstr(s), addr, size, bind<<4|typ&0xf, elfshnum, other)
-	x.Elfsym = int32(ctxt.numelfsym)
+	ctxt.loader.SetSymElfSym(loader.Sym(x.SymIdx), int32(ctxt.numelfsym))
 	ctxt.numelfsym++
 }
 
 func putelfsectionsym(ctxt *Link, out *OutBuf, s *sym.Symbol, shndx int) {
 	putelfsyment(out, 0, 0, 0, STB_LOCAL<<4|STT_SECTION, shndx, 0)
-	s.Elfsym = int32(ctxt.numelfsym)
+	ctxt.loader.SetSymElfSym(loader.Sym(s.SymIdx), int32(ctxt.numelfsym))
 	ctxt.numelfsym++
 }
 

src/cmd/link/internal/mips/asm.go

@@ -54,7 +54,7 @@ func adddynrel(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s *sym.
 func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 	ctxt.Out.Write32(uint32(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	switch r.Type {
 	default:
 		return false

src/cmd/link/internal/mips64/asm.go

@@ -61,7 +61,7 @@ func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 
 	ctxt.Out.Write64(uint64(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	ctxt.Out.Write32(uint32(elfsym))
 	ctxt.Out.Write8(0)
 	ctxt.Out.Write8(0)

src/cmd/link/internal/ppc64/asm.go

@@ -453,7 +453,7 @@ func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 	}
 	ctxt.Out.Write64(uint64(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	switch r.Type {
 	default:
 		return false

src/cmd/link/internal/s390x/asm.go

@@ -224,7 +224,7 @@ func adddynrel2(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s load
 func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 	ctxt.Out.Write64(uint64(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	switch r.Type {
 	default:
 		return false

src/cmd/link/internal/sym/sizeof_test.go

@@ -21,7 +21,7 @@ func TestSizeof(t *testing.T) {
 		_32bit uintptr     // size on 32bit platforms
 		_64bit uintptr     // size on 64bit platforms
 	}{
-		{Symbol{}, 92, 144},
+		{Symbol{}, 84, 136},
 	}
 
 	for _, tt := range tests {

src/cmd/link/internal/sym/symbol.go

@@ -15,21 +15,19 @@ import (
 
 // Symbol is an entry in the symbol table.
 type Symbol struct {
-	Name        string
+	Name    string
-	Type        SymKind
+	Type    SymKind
-	Version     int16
+	Version int16
-	Attr        Attribute
+	Attr    Attribute
-	Dynid       int32
+	Dynid   int32
-	Align       int32
+	Align   int32
-	Elfsym      int32
+	Value   int64
-	LocalElfsym int32
+	Size    int64
-	Value       int64
+	Sub     *Symbol
-	Size        int64
+	Outer   *Symbol
-	Sub         *Symbol
+	SymIdx  LoaderSym
-	Outer       *Symbol
+	auxinfo *AuxSymbol
-	SymIdx      LoaderSym
+	Sect    *Section
-	auxinfo     *AuxSymbol
-	Sect        *Section
 	// P contains the raw symbol data.
 	P []byte
 	R []Reloc
@@ -86,16 +84,6 @@ func (s *Symbol) IsFileLocal() bool {
 	return s.Version >= SymVerStatic
 }
 
-func (s *Symbol) ElfsymForReloc() int32 {
-	// If putelfsym created a local version of this symbol, use that in all
-	// relocations.
-	if s.LocalElfsym != 0 {
-		return s.LocalElfsym
-	} else {
-		return s.Elfsym
-	}
-}
-
 func (s *Symbol) Len() int64 {
 	return s.Size
 }

src/cmd/link/internal/x86/asm.go

@@ -343,7 +343,7 @@ func adddynrel2(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s load
 func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
 	ctxt.Out.Write32(uint32(sectoff))
 
-	elfsym := r.Xsym.ElfsymForReloc()
+	elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
 	switch r.Type {
 	default:
 		return false