cmd/link: move ElfType field in sym.Symbol to cold section

The sym.Symbol 'ElfType' field is used only for symbols corresponding
to things in imported shared libraries, hence is not needed in the
common case. Relocate it to sym.AuxSymbol so as to shrink the main
Symbol struct.

Updates #26186

Change-Id: I803efc561c31a0ca1d93eca434fda1c862a7b2c5
Reviewed-on: https://go-review.googlesource.com/125479
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/cmd/link/internal/amd64/asm.go b/src/cmd/link/internal/amd64/asm.go
index 829635d219763efb7b736984cc63e05da04ac0b3..e922fe2db94ee5982fdb05a3f563ce4038b86438 100644 (file)
--- a/src/cmd/link/internal/amd64/asm.go
+++ b/src/cmd/link/internal/amd64/asm.go
@@ -410,7 +410,7 @@ func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
                }
        case objabi.R_PCREL:
                if r.Siz == 4 {
-                       if r.Xsym.Type == sym.SDYNIMPORT && r.Xsym.ElfType == elf.STT_FUNC {
+                       if r.Xsym.Type == sym.SDYNIMPORT && r.Xsym.ElfType() == elf.STT_FUNC {
                                ctxt.Out.Write64(uint64(elf.R_X86_64_PLT32) | uint64(elfsym)<<32)
                        } else {
                                ctxt.Out.Write64(uint64(elf.R_X86_64_PC32) | uint64(elfsym)<<32)

diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index 511cdd891a283e42d40d982ed7d4391059cab883..331b6ca6145edd971e76f02cfacc47f5ed483bf7 100644 (file)
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -1706,7 +1706,7 @@ func ldshlibsyms(ctxt *Link, shlib string) {
                        continue
                }
                lsym.Type = sym.SDYNIMPORT
-               lsym.ElfType = elf.ST_TYPE(elfsym.Info)
+               lsym.SetElfType(elf.ST_TYPE(elfsym.Info))
                lsym.Size = int64(elfsym.Size)
                if elfsym.Section != elf.SHN_UNDEF {
                        // Set .File for the library that actually defines the symbol.

diff --git a/src/cmd/link/internal/ld/symtab.go b/src/cmd/link/internal/ld/symtab.go
index 88d476710b93795df4b1549adc6e6d514055237a..2a04ef3824eba87345371e515a32c35f4691daf9 100644 (file)
--- a/src/cmd/link/internal/ld/symtab.go
+++ b/src/cmd/link/internal/ld/symtab.go
@@ -93,7 +93,7 @@ func putelfsym(ctxt *Link, x *sym.Symbol, s string, t SymbolType, addr int64, go
        case UndefinedSym:
                // ElfType is only set for symbols read from Go shared libraries, but
                // for other symbols it is left as STT_NOTYPE which is fine.
-               typ = int(x.ElfType)
+               typ = int(x.ElfType())
 
        case TLSSym:
                typ = STT_TLS

diff --git a/src/cmd/link/internal/s390x/asm.go b/src/cmd/link/internal/s390x/asm.go
index 245da19d9d86187520a9f3000299c6b6b3448080..88199f3a562c751bc51dd4c37dec3c4c35434e90 100644 (file)
--- a/src/cmd/link/internal/s390x/asm.go
+++ b/src/cmd/link/internal/s390x/asm.go
@@ -285,7 +285,7 @@ func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
                case objabi.R_PCRELDBL, objabi.R_CALL:
                        isdbl = true
                }
-               if r.Xsym.Type == sym.SDYNIMPORT && (r.Xsym.ElfType == elf.STT_FUNC || r.Type == objabi.R_CALL) {
+               if r.Xsym.Type == sym.SDYNIMPORT && (r.Xsym.ElfType() == elf.STT_FUNC || r.Type == objabi.R_CALL) {
                        if isdbl {
                                switch r.Siz {
                                case 2:

diff --git a/src/cmd/link/internal/sym/sizeof_test.go b/src/cmd/link/internal/sym/sizeof_test.go
index a9bc174d59f9d504decd7bf2958dbd01de5d1019..da4602a1619e7aea7786d05a6f8c0cf694c3b839 100644 (file)
--- a/src/cmd/link/internal/sym/sizeof_test.go
+++ b/src/cmd/link/internal/sym/sizeof_test.go
@@ -23,7 +23,7 @@ func TestSizeof(t *testing.T) {
                _32bit uintptr     // size on 32bit platforms
                _64bit uintptr     // size on 64bit platforms
        }{
-               {Symbol{}, 112, 184},
+               {Symbol{}, 108, 176},
        }
 
        for _, tt := range tests {

diff --git a/src/cmd/link/internal/sym/symbol.go b/src/cmd/link/internal/sym/symbol.go
index c05b82a6657787e52bc0130320864639022eec30..95ad8654b5cef1d39a6a51720af08a4147747358 100644 (file)
--- a/src/cmd/link/internal/sym/symbol.go
+++ b/src/cmd/link/internal/sym/symbol.go
@@ -24,18 +24,14 @@ type Symbol struct {
        LocalElfsym int32
        Value       int64
        Size        int64
-       // ElfType is set for symbols read from shared libraries by ldshlibsyms. It
-       // is not set for symbols defined by the packages being linked or by symbols
-       // read by ldelf (and so is left as elf.STT_NOTYPE).
-       ElfType  elf.SymType
-       Sub      *Symbol
-       Outer    *Symbol
-       Gotype   *Symbol
-       File     string
-       auxinfo  *AuxSymbol
-       Sect     *Section
-       FuncInfo *FuncInfo
-       Lib      *Library // Package defining this symbol
+       Sub         *Symbol
+       Outer       *Symbol
+       Gotype      *Symbol
+       File        string
+       auxinfo     *AuxSymbol
+       Sect        *Section
+       FuncInfo    *FuncInfo
+       Lib         *Library // Package defining this symbol
        // P contains the raw symbol data.
        P []byte
        R []Reloc
@@ -49,6 +45,10 @@ type AuxSymbol struct {
        localentry uint8
        plt        int32
        got        int32
+       // ElfType is set for symbols read from shared libraries by ldshlibsyms. It
+       // is not set for symbols defined by the packages being linked or by symbols
+       // read by ldelf (and so is left as elf.STT_NOTYPE).
+       elftype elf.SymType
 }
 
 func (s *Symbol) String() string {
@@ -378,6 +378,23 @@ func (s *Symbol) SetGot(val int32) {
        s.auxinfo.got = val
 }
 
+func (s *Symbol) ElfType() elf.SymType {
+       if s.auxinfo == nil {
+               return elf.STT_NOTYPE
+       }
+       return s.auxinfo.elftype
+}
+
+func (s *Symbol) SetElfType(val elf.SymType) {
+       if s.auxinfo == nil {
+               if val == elf.STT_NOTYPE {
+                       return
+               }
+               s.makeAuxInfo()
+       }
+       s.auxinfo.elftype = val
+}
+
 // SortSub sorts a linked-list (by Sub) of *Symbol by Value.
 // Used for sub-symbols when loading host objects (see e.g. ldelf.go).
 func SortSub(l *Symbol) *Symbol {