作者：tidatid
项目：g
func machoreloc1(r *ld.Reloc, sectoff int64) int {
var v uint32
rs := r.Xsym
if rs.Type == ld.SHOSTOBJ || r.Type == ld.R_PCREL {
if rs.Dynid < 0 {
ld.Diag("reloc %d to non-macho symbol %s type=%d", r.Type, rs.Name, rs.Type)
return -1
}
v = uint32(rs.Dynid)
v |= 1 << 27 // external relocation
} else {
v = uint32((rs.Sect.(*ld.Section)).Extnum)
if v == 0 {
ld.Diag("reloc %d to symbol %s in non-macho section %s type=%d", r.Type, rs.Name, (rs.Sect.(*ld.Section)).Name, rs.Type)
return -1
}
}
switch r.Type {
default:
return -1
case ld.R_ADDR:
v |= ld.MACHO_X86_64_RELOC_UNSIGNED << 28
case ld.R_CALL:
v |= 1 << 24 // pc-relative bit
v |= ld.MACHO_X86_64_RELOC_BRANCH << 28
// NOTE: Only works with 'external' relocation. Forced above.
case ld.R_PCREL:
v |= 1 << 24 // pc-relative bit
v |= ld.MACHO_X86_64_RELOC_SIGNED << 28
}
switch r.Siz {
default:
return -1
case 1:
v |= 0 << 25
case 2:
v |= 1 << 25
case 4:
v |= 2 << 25
case 8:
v |= 3 << 25
}
ld.Thearch.Lput(uint32(sectoff))
ld.Thearch.Lput(v)
return 0
}
作者：xslonepiec
项目：goio
func machoreloc1(r *ld.Reloc, sectoff int64) int {
var v uint32
rs := r.Xsym
if rs.Type == ld.SHOSTOBJ {
if rs.Dynid < 0 {
ld.Diag("reloc %d to non-macho symbol %s type=%d", r.Type, rs.Name, rs.Type)
return -1
}
v = uint32(rs.Dynid)
v |= 1 << 27 // external relocation
} else {
v = uint32((rs.Sect.(*ld.Section)).Extnum)
if v == 0 {
ld.Diag("reloc %d to symbol %s in non-macho section %s type=%d", r.Type, rs.Name, (rs.Sect.(*ld.Section)).Name, rs.Type)
return -1
}
}
switch r.Type {
default:
return -1
case ld.R_ADDR:
v |= ld.MACHO_GENERIC_RELOC_VANILLA << 28
case ld.R_CALL,
ld.R_PCREL:
v |= 1 << 24 // pc-relative bit
v |= ld.MACHO_GENERIC_RELOC_VANILLA << 28
}
switch r.Siz {
default:
return -1
case 1:
v |= 0 << 25
case 2:
v |= 1 << 25
case 4:
v |= 2 << 25
case 8:
v |= 3 << 25
}
ld.Thearch.Lput(uint32(sectoff))
ld.Thearch.Lput(v)
return 0
}
作者：tidatid
项目：g
func adddynsym(ctxt *ld.Link, s *ld.LSym) {
if s.Dynid >= 0 {
return
}
if ld.Iself {
s.Dynid = int32(ld.Nelfsym)
ld.Nelfsym++
d := ld.Linklookup(ctxt, ".dynsym", 0)
name := s.Extname
ld.Adduint32(ctxt, d, uint32(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), name)))
/* type */
t := ld.STB_GLOBAL << 4
if s.Cgoexport != 0 && s.Type&ld.SMASK == ld.STEXT {
t |= ld.STT_FUNC
} else {
t |= ld.STT_OBJECT
}
ld.Adduint8(ctxt, d, uint8(t))
/* reserved */
ld.Adduint8(ctxt, d, 0)
/* section where symbol is defined */
if s.Type == ld.SDYNIMPORT {
ld.Adduint16(ctxt, d, ld.SHN_UNDEF)
} else {
ld.Adduint16(ctxt, d, 1)
}
/* value */
if s.Type == ld.SDYNIMPORT {
ld.Adduint64(ctxt, d, 0)
} else {
ld.Addaddr(ctxt, d, s)
}
/* size of object */
ld.Adduint64(ctxt, d, uint64(s.Size))
if s.Cgoexport&ld.CgoExportDynamic == 0 && s.Dynimplib != "" && needlib(s.Dynimplib) != 0 {
ld.Elfwritedynent(ld.Linklookup(ctxt, ".dynamic", 0), ld.DT_NEEDED, uint64(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), s.Dynimplib)))
}
} else if ld.HEADTYPE == ld.Hdarwin {
ld.Diag("adddynsym: missed symbol %s (%s)", s.Name, s.Extname)
} else if ld.HEADTYPE == ld.Hwindows {
} else // already taken care of
{
ld.Diag("adddynsym: unsupported binary format")
}
}
作者：xslonepiec
项目：goio
func adddynsym(ctxt *ld.Link, s *ld.LSym) {
if s.Dynid >= 0 {
return
}
if ld.Iself {
s.Dynid = int32(ld.Nelfsym)
ld.Nelfsym++
d := ld.Linklookup(ctxt, ".dynsym", 0)
/* name */
name := s.Extname
ld.Adduint32(ctxt, d, uint32(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), name)))
/* value */
if s.Type == ld.SDYNIMPORT {
ld.Adduint32(ctxt, d, 0)
} else {
ld.Addaddr(ctxt, d, s)
}
/* size */
ld.Adduint32(ctxt, d, 0)
/* type */
t := ld.STB_GLOBAL << 4
if s.Cgoexport != 0 && s.Type&ld.SMASK == ld.STEXT {
t |= ld.STT_FUNC
} else {
t |= ld.STT_OBJECT
}
ld.Adduint8(ctxt, d, uint8(t))
ld.Adduint8(ctxt, d, 0)
/* shndx */
if s.Type == ld.SDYNIMPORT {
ld.Adduint16(ctxt, d, ld.SHN_UNDEF)
} else {
ld.Adduint16(ctxt, d, 1)
}
} else if ld.HEADTYPE == ld.Hdarwin {
ld.Diag("adddynsym: missed symbol %s (%s)", s.Name, s.Extname)
} else if ld.HEADTYPE == ld.Hwindows {
} else // already taken care of
{
ld.Diag("adddynsym: unsupported binary format")
}
}
作者：tidatid
项目：g
func pereloc1(r *ld.Reloc, sectoff int64) bool {
var v uint32
rs := r.Xsym
if rs.Dynid < 0 {
ld.Diag("reloc %d to non-coff symbol %s type=%d", r.Type, rs.Name, rs.Type)
return false
}
ld.Thearch.Lput(uint32(sectoff))
ld.Thearch.Lput(uint32(rs.Dynid))
switch r.Type {
default:
return false
case ld.R_ADDR:
if r.Siz == 8 {
v = ld.IMAGE_REL_AMD64_ADDR64
} else {
v = ld.IMAGE_REL_AMD64_ADDR32
}
case ld.R_CALL,
ld.R_PCREL:
v = ld.IMAGE_REL_AMD64_REL32
}
ld.Thearch.Wput(uint16(v))
return true
}
作者：xslonepiec
项目：goio
func addpltsym(ctxt *ld.Link, s *ld.LSym) {
if s.Plt >= 0 {
return
}
adddynsym(ctxt, s)
if ld.Iself {
plt := ld.Linklookup(ctxt, ".plt", 0)
got := ld.Linklookup(ctxt, ".got.plt", 0)
rel := ld.Linklookup(ctxt, ".rel.plt", 0)
if plt.Size == 0 {
elfsetupplt()
}
// jmpq *got+size
ld.Adduint8(ctxt, plt, 0xff)
ld.Adduint8(ctxt, plt, 0x25)
ld.Addaddrplus(ctxt, plt, got, got.Size)
// add to got: pointer to current pos in plt
ld.Addaddrplus(ctxt, got, plt, plt.Size)
// pushl $x
ld.Adduint8(ctxt, plt, 0x68)
ld.Adduint32(ctxt, plt, uint32(rel.Size))
// jmp .plt
ld.Adduint8(ctxt, plt, 0xe9)
ld.Adduint32(ctxt, plt, uint32(-(plt.Size + 4)))
// rel
ld.Addaddrplus(ctxt, rel, got, got.Size-4)
ld.Adduint32(ctxt, rel, ld.ELF32_R_INFO(uint32(s.Dynid), ld.R_386_JMP_SLOT))
s.Plt = int32(plt.Size - 16)
} else if ld.HEADTYPE == ld.Hdarwin {
// Same laziness as in 6l.
plt := ld.Linklookup(ctxt, ".plt", 0)
addgotsym(ctxt, s)
ld.Adduint32(ctxt, ld.Linklookup(ctxt, ".linkedit.plt", 0), uint32(s.Dynid))
// jmpq *got+size(IP)
s.Plt = int32(plt.Size)
ld.Adduint8(ctxt, plt, 0xff)
ld.Adduint8(ctxt, plt, 0x25)
ld.Addaddrplus(ctxt, plt, ld.Linklookup(ctxt, ".got", 0), int64(s.Got))
} else {
ld.Diag("addpltsym: unsupported binary format")
}
}
作者：xslonepiec
项目：goio
func addgotsyminternal(ctxt *ld.Link, s *ld.LSym) {
if s.Got >= 0 {
return
}
got := ld.Linklookup(ctxt, ".got", 0)
s.Got = int32(got.Size)
ld.Addaddrplus(ctxt, got, s, 0)
if ld.Iself {
} else {
ld.Diag("addgotsyminternal: unsupported binary format")
}
}
作者：kluesk
项目：go-akaro
func adddynlib(lib string) {
if needlib(lib) == 0 {
return
}
if ld.Iself {
s := ld.Linklookup(ld.Ctxt, ".dynstr", 0)
if s.Size == 0 {
ld.Addstring(s, "")
}
ld.Elfwritedynent(ld.Linklookup(ld.Ctxt, ".dynamic", 0), ld.DT_NEEDED, uint64(ld.Addstring(s, lib)))
} else {
ld.Diag("adddynlib: unsupported binary format")
}
}
作者：kluesk
项目：go-akaro
// Return the value of .TOC. for symbol s
func symtoc(s *ld.LSym) int64 {
var toc *ld.LSym
if s.Outer != nil {
toc = ld.Linkrlookup(ld.Ctxt, ".TOC.", int(s.Outer.Version))
} else {
toc = ld.Linkrlookup(ld.Ctxt, ".TOC.", int(s.Version))
}
if toc == nil {
ld.Diag("TOC-relative relocation in object without .TOC.")
return 0
}
return toc.Value
}
作者：kluesk
项目：go-akaro
func adddynsym(ctxt *ld.Link, s *ld.LSym) {
if s.Dynid >= 0 {
return
}
if ld.Iself {
s.Dynid = int32(ld.Nelfsym)
ld.Nelfsym++
d := ld.Linklookup(ctxt, ".dynsym", 0)
name := s.Extname
ld.Adduint32(ctxt, d, uint32(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), name)))
/* type */
t := ld.STB_GLOBAL << 4
if s.Cgoexport != 0 && s.Type&ld.SMASK == ld.STEXT {
t |= ld.STT_FUNC
} else {
t |= ld.STT_OBJECT
}
ld.Adduint8(ctxt, d, uint8(t))
/* reserved */
ld.Adduint8(ctxt, d, 0)
/* section where symbol is defined */
if s.Type == ld.SDYNIMPORT {
ld.Adduint16(ctxt, d, ld.SHN_UNDEF)
} else {
ld.Adduint16(ctxt, d, 1)
}
/* value */
if s.Type == ld.SDYNIMPORT {
ld.Adduint64(ctxt, d, 0)
} else {
ld.Addaddr(ctxt, d, s)
}
/* size of object */
ld.Adduint64(ctxt, d, uint64(s.Size))
} else {
ld.Diag("adddynsym: unsupported binary format")
}
}
作者：xslonepiec
项目：goio
func addgotsym(ctxt *ld.Link, s *ld.LSym) {
if s.Got >= 0 {
return
}
adddynsym(ctxt, s)
got := ld.Linklookup(ctxt, ".got", 0)
s.Got = int32(got.Size)
ld.Adduint32(ctxt, got, 0)
if ld.Iself {
rel := ld.Linklookup(ctxt, ".rel", 0)
ld.Addaddrplus(ctxt, rel, got, int64(s.Got))
ld.Adduint32(ctxt, rel, ld.ELF32_R_INFO(uint32(s.Dynid), ld.R_ARM_GLOB_DAT))
} else {
ld.Diag("addgotsym: unsupported binary format")
}
}
作者：kluesk
项目：go-akaro
func addpltsym(ctxt *ld.Link, s *ld.LSym) {
if s.Plt >= 0 {
return
}
adddynsym(ctxt, s)
if ld.Iself {
plt := ld.Linklookup(ctxt, ".plt", 0)
rela := ld.Linklookup(ctxt, ".rela.plt", 0)
if plt.Size == 0 {
elfsetupplt()
}
// Create the glink resolver if necessary
glink := ensureglinkresolver()
// Write symbol resolver stub (just a branch to the
// glink resolver stub)
r := ld.Addrel(glink)
r.Sym = glink
r.Off = int32(glink.Size)
r.Siz = 4
r.Type = ld.R_CALLPOWER
ld.Adduint32(ctxt, glink, 0x48000000) // b .glink
// In the ppc64 ABI, the dynamic linker is responsible
// for writing the entire PLT. We just need to
// reserve 8 bytes for each PLT entry and generate a
// JMP_SLOT dynamic relocation for it.
//
// TODO(austin): ABI v1 is different
s.Plt = int32(plt.Size)
plt.Size += 8
ld.Addaddrplus(ctxt, rela, plt, int64(s.Plt))
ld.Adduint64(ctxt, rela, ld.ELF64_R_INFO(uint32(s.Dynid), ld.R_PPC64_JMP_SLOT))
ld.Adduint64(ctxt, rela, 0)
} else {
ld.Diag("addpltsym: unsupported binary format")
}
}
作者：tidatid
项目：g
func addgotsym(s *ld.LSym) {
if s.Got >= 0 {
return
}
adddynsym(ld.Ctxt, s)
got := ld.Linklookup(ld.Ctxt, ".got", 0)
s.Got = int32(got.Size)
ld.Adduint64(ld.Ctxt, got, 0)
if ld.Iself {
rela := ld.Linklookup(ld.Ctxt, ".rela", 0)
ld.Addaddrplus(ld.Ctxt, rela, got, int64(s.Got))
ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(s.Dynid), ld.R_X86_64_GLOB_DAT))
ld.Adduint64(ld.Ctxt, rela, 0)
} else if ld.HEADTYPE == ld.Hdarwin {
ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.got", 0), uint32(s.Dynid))
} else {
ld.Diag("addgotsym: unsupported binary format")
}
}
作者：kluesk
项目：go-akaro
func adddynrel(s *ld.LSym, r *ld.Reloc) {
targ := r.Sym
ld.Ctxt.Cursym = s
switch r.Type {
default:
if r.Type >= 256 {
ld.Diag("unexpected relocation type %d", r.Type)
return
}
// Handle relocations found in ELF object files.
case 256 + ld.R_PPC64_REL24:
r.Type = ld.R_CALLPOWER
// This is a local call, so the caller isn't setting
// up r12 and r2 is the same for the caller and
// callee. Hence, we need to go to the local entry
// point. (If we don't do this, the callee will try
// to use r12 to compute r2.)
r.Add += int64(r.Sym.Localentry) * 4
if targ.Type == ld.SDYNIMPORT {
// Should have been handled in elfsetupplt
ld.Diag("unexpected R_PPC64_REL24 for dyn import")
}
return
case 256 + ld.R_PPC64_ADDR64:
r.Type = ld.R_ADDR
if targ.Type == ld.SDYNIMPORT {
// These happen in .toc sections
adddynsym(ld.Ctxt, targ)
rela := ld.Linklookup(ld.Ctxt, ".rela", 0)
ld.Addaddrplus(ld.Ctxt, rela, s, int64(r.Off))
ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(targ.Dynid), ld.R_PPC64_ADDR64))
ld.Adduint64(ld.Ctxt, rela, uint64(r.Add))
r.Type = 256 // ignore during relocsym
}
return
case 256 + ld.R_PPC64_TOC16:
r.Type = ld.R_POWER_TOC
r.Variant = ld.RV_POWER_LO | ld.RV_CHECK_OVERFLOW
return
case 256 + ld.R_PPC64_TOC16_LO:
r.Type = ld.R_POWER_TOC
r.Variant = ld.RV_POWER_LO
return
case 256 + ld.R_PPC64_TOC16_HA:
r.Type = ld.R_POWER_TOC
r.Variant = ld.RV_POWER_HA | ld.RV_CHECK_OVERFLOW
return
case 256 + ld.R_PPC64_TOC16_HI:
r.Type = ld.R_POWER_TOC
r.Variant = ld.RV_POWER_HI | ld.RV_CHECK_OVERFLOW
return
case 256 + ld.R_PPC64_TOC16_DS:
r.Type = ld.R_POWER_TOC
r.Variant = ld.RV_POWER_DS | ld.RV_CHECK_OVERFLOW
return
case 256 + ld.R_PPC64_TOC16_LO_DS:
r.Type = ld.R_POWER_TOC
r.Variant = ld.RV_POWER_DS
return
case 256 + ld.R_PPC64_REL16_LO:
r.Type = ld.R_PCREL
r.Variant = ld.RV_POWER_LO
r.Add += 2 // Compensate for relocation size of 2
return
case 256 + ld.R_PPC64_REL16_HI:
r.Type = ld.R_PCREL
r.Variant = ld.RV_POWER_HI | ld.RV_CHECK_OVERFLOW
r.Add += 2
return
case 256 + ld.R_PPC64_REL16_HA:
r.Type = ld.R_PCREL
r.Variant = ld.RV_POWER_HA | ld.RV_CHECK_OVERFLOW
r.Add += 2
return
}
// Handle references to ELF symbols from our own object files.
if targ.Type != ld.SDYNIMPORT {
return
}
// TODO(austin): Translate our relocations to ELF
//.........这里部分代码省略.........
作者：kluesk
项目：go-akaro
func archrelocvariant(r *ld.Reloc, s *ld.LSym, t int64) int64 {
switch r.Variant & ld.RV_TYPE_MASK {
default:
ld.Diag("unexpected relocation variant %d", r.Variant)
fallthrough
case ld.RV_NONE:
return t
case ld.RV_POWER_LO:
if r.Variant&ld.RV_CHECK_OVERFLOW != 0 {
// Whether to check for signed or unsigned
// overflow depends on the instruction
var o1 uint32
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
o1 = ld.Be32(s.P[r.Off-2:])
} else {
o1 = ld.Le32(s.P[r.Off:])
}
switch o1 >> 26 {
case 24, // ori
26, // xori
28: // andi
if t>>16 != 0 {
goto overflow
}
default:
if int64(int16(t)) != t {
goto overflow
}
}
}
return int64(int16(t))
case ld.RV_POWER_HA:
t += 0x8000
fallthrough
// Fallthrough
case ld.RV_POWER_HI:
t >>= 16
if r.Variant&ld.RV_CHECK_OVERFLOW != 0 {
// Whether to check for signed or unsigned
// overflow depends on the instruction
var o1 uint32
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
o1 = ld.Be32(s.P[r.Off-2:])
} else {
o1 = ld.Le32(s.P[r.Off:])
}
switch o1 >> 26 {
case 25, // oris
27, // xoris
29: // andis
if t>>16 != 0 {
goto overflow
}
default:
if int64(int16(t)) != t {
goto overflow
}
}
}
return int64(int16(t))
case ld.RV_POWER_DS:
var o1 uint32
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
o1 = uint32(ld.Be16(s.P[r.Off:]))
} else {
o1 = uint32(ld.Le16(s.P[r.Off:]))
}
if t&3 != 0 {
ld.Diag("relocation for %s+%d is not aligned: %d", r.Sym.Name, r.Off, t)
}
if (r.Variant&ld.RV_CHECK_OVERFLOW != 0) && int64(int16(t)) != t {
goto overflow
}
return int64(o1)&0x3 | int64(int16(t))
}
overflow:
ld.Diag("relocation for %s+%d is too big: %d", r.Sym.Name, r.Off, t)
return t
}
作者：bibbyflyawa
项目：g
func machoreloc1(r *ld.Reloc, sectoff int64) int {
var v uint32
rs := r.Xsym
// ld64 has a bug handling MACHO_ARM64_RELOC_UNSIGNED with !extern relocation.
// see cmd/internal/ld/data.go for details. The workarond is that don't use !extern
// UNSIGNED relocation at all.
if rs.Type == obj.SHOSTOBJ || r.Type == obj.R_CALLARM64 || r.Type == obj.R_ADDRARM64 || r.Type == obj.R_ADDR {
if rs.Dynid < 0 {
ld.Diag("reloc %d to non-macho symbol %s type=%d", r.Type, rs.Name, rs.Type)
return -1
}
v = uint32(rs.Dynid)
v |= 1 << 27 // external relocation
} else {
v = uint32((rs.Sect.(*ld.Section)).Extnum)
if v == 0 {
ld.Diag("reloc %d to symbol %s in non-macho section %s type=%d", r.Type, rs.Name, (rs.Sect.(*ld.Section)).Name, rs.Type)
return -1
}
}
switch r.Type {
default:
return -1
case obj.R_ADDR:
v |= ld.MACHO_ARM64_RELOC_UNSIGNED << 28
case obj.R_CALLARM64:
if r.Xadd != 0 {
ld.Diag("ld64 doesn't allow BR26 reloc with non-zero addend: %s+%d", rs.Name, r.Xadd)
}
v |= 1 << 24 // pc-relative bit
v |= ld.MACHO_ARM64_RELOC_BRANCH26 << 28
case obj.R_ADDRARM64:
r.Siz = 4
// Two relocation entries: MACHO_ARM64_RELOC_PAGEOFF12 MACHO_ARM64_RELOC_PAGE21
// if r.Xadd is non-zero, add two MACHO_ARM64_RELOC_ADDEND.
if r.Xadd != 0 {
ld.Thearch.Lput(uint32(sectoff + 4))
ld.Thearch.Lput((ld.MACHO_ARM64_RELOC_ADDEND << 28) | (2 << 25) | uint32(r.Xadd&0xffffff))
}
ld.Thearch.Lput(uint32(sectoff + 4))
ld.Thearch.Lput(v | (ld.MACHO_ARM64_RELOC_PAGEOFF12 << 28) | (2 << 25))
if r.Xadd != 0 {
ld.Thearch.Lput(uint32(sectoff))
ld.Thearch.Lput((ld.MACHO_ARM64_RELOC_ADDEND << 28) | (2 << 25) | uint32(r.Xadd&0xffffff))
}
v |= 1 << 24 // pc-relative bit
v |= ld.MACHO_ARM64_RELOC_PAGE21 << 28
}
switch r.Siz {
default:
return -1
case 1:
v |= 0 << 25
case 2:
v |= 1 << 25
case 4:
v |= 2 << 25
case 8:
v |= 3 << 25
}
ld.Thearch.Lput(uint32(sectoff))
ld.Thearch.Lput(v)
return 0
}
作者：xslonepiec
项目：goio
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int {
if ld.Linkmode == ld.LinkExternal {
switch r.Type {
case ld.R_CALLARM:
r.Done = 0
// set up addend for eventual relocation via outer symbol.
rs := r.Sym
r.Xadd = r.Add
if r.Xadd&0x800000 != 0 {
r.Xadd |= ^0xffffff
}
r.Xadd *= 4
for rs.Outer != nil {
r.Xadd += ld.Symaddr(rs) - ld.Symaddr(rs.Outer)
rs = rs.Outer
}
if rs.Type != ld.SHOSTOBJ && rs.Sect == nil {
ld.Diag("missing section for %s", rs.Name)
}
r.Xsym = rs
// ld64 for arm seems to want the symbol table to contain offset
// into the section rather than pseudo virtual address that contains
// the section load address.
// we need to compensate that by removing the instruction's address
// from addend.
if ld.HEADTYPE == ld.Hdarwin {
r.Xadd -= ld.Symaddr(s) + int64(r.Off)
}
*val = int64(braddoff(int32(0xff000000&uint32(r.Add)), int32(0xffffff&uint32(r.Xadd/4))))
return 0
}
return -1
}
switch r.Type {
case ld.R_CONST:
*val = r.Add
return 0
case ld.R_GOTOFF:
*val = ld.Symaddr(r.Sym) + r.Add - ld.Symaddr(ld.Linklookup(ld.Ctxt, ".got", 0))
return 0
// The following three arch specific relocations are only for generation of
// Linux/ARM ELF's PLT entry (3 assembler instruction)
case ld.R_PLT0: // add ip, pc, #0xXX00000
if ld.Symaddr(ld.Linklookup(ld.Ctxt, ".got.plt", 0)) < ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0)) {
ld.Diag(".got.plt should be placed after .plt section.")
}
*val = 0xe28fc600 + (0xff & (int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0))+int64(r.Off))+r.Add)) >> 20))
return 0
case ld.R_PLT1: // add ip, ip, #0xYY000
*val = 0xe28cca00 + (0xff & (int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0))+int64(r.Off))+r.Add+4)) >> 12))
return 0
case ld.R_PLT2: // ldr pc, [ip, #0xZZZ]!
*val = 0xe5bcf000 + (0xfff & int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0))+int64(r.Off))+r.Add+8)))
return 0
case ld.R_CALLARM: // bl XXXXXX or b YYYYYY
*val = int64(braddoff(int32(0xff000000&uint32(r.Add)), int32(0xffffff&uint32((ld.Symaddr(r.Sym)+int64((uint32(r.Add))*4)-(s.Value+int64(r.Off)))/4))))
return 0
}
return -1
}
作者：tidatid
项目：g
func asmb() {
if ld.Debug['v'] != 0 {
fmt.Fprintf(&ld.Bso, "%5.2f asmb\n", obj.Cputime())
}
ld.Bflush(&ld.Bso)
if ld.Debug['v'] != 0 {
fmt.Fprintf(&ld.Bso, "%5.2f codeblk\n", obj.Cputime())
}
ld.Bflush(&ld.Bso)
if ld.Iself {
ld.Asmbelfsetup()
}
sect := ld.Segtext.Sect
ld.Cseek(int64(sect.Vaddr - ld.Segtext.Vaddr + ld.Segtext.Fileoff))
ld.Codeblk(int64(sect.Vaddr), int64(sect.Length))
for sect = sect.Next; sect != nil; sect = sect.Next {
ld.Cseek(int64(sect.Vaddr - ld.Segtext.Vaddr + ld.Segtext.Fileoff))
ld.Datblk(int64(sect.Vaddr), int64(sect.Length))
}
if ld.Segrodata.Filelen > 0 {
if ld.Debug['v'] != 0 {
fmt.Fprintf(&ld.Bso, "%5.2f rodatblk\n", obj.Cputime())
}
ld.Bflush(&ld.Bso)
ld.Cseek(int64(ld.Segrodata.Fileoff))
ld.Datblk(int64(ld.Segrodata.Vaddr), int64(ld.Segrodata.Filelen))
}
if ld.Debug['v'] != 0 {
fmt.Fprintf(&ld.Bso, "%5.2f datblk\n", obj.Cputime())
}
ld.Bflush(&ld.Bso)
ld.Cseek(int64(ld.Segdata.Fileoff))
ld.Datblk(int64(ld.Segdata.Vaddr), int64(ld.Segdata.Filelen))
machlink := int64(0)
if ld.HEADTYPE == ld.Hdarwin {
if ld.Debug['v'] != 0 {
fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime())
}
dwarfoff := ld.Rnd(int64(uint64(ld.HEADR)+ld.Segtext.Length), int64(ld.INITRND)) + ld.Rnd(int64(ld.Segdata.Filelen), int64(ld.INITRND))
ld.Cseek(dwarfoff)
ld.Segdwarf.Fileoff = uint64(ld.Cpos())
ld.Dwarfemitdebugsections()
ld.Segdwarf.Filelen = uint64(ld.Cpos()) - ld.Segdwarf.Fileoff
machlink = ld.Domacholink()
}
switch ld.HEADTYPE {
default:
ld.Diag("unknown header type %d", ld.HEADTYPE)
fallthrough
case ld.Hplan9,
ld.Helf:
break
case ld.Hdarwin:
ld.Debug['8'] = 1 /* 64-bit addresses */
case ld.Hlinux,
ld.Hfreebsd,
ld.Hnetbsd,
ld.Hopenbsd,
ld.Hdragonfly,
ld.Hsolaris:
ld.Debug['8'] = 1 /* 64-bit addresses */
case ld.Hnacl,
ld.Hwindows:
break
}
ld.Symsize = 0
ld.Spsize = 0
ld.Lcsize = 0
symo := int64(0)
if ld.Debug['s'] == 0 {
if ld.Debug['v'] != 0 {
fmt.Fprintf(&ld.Bso, "%5.2f sym\n", obj.Cputime())
}
ld.Bflush(&ld.Bso)
switch ld.HEADTYPE {
default:
case ld.Hplan9,
ld.Helf:
ld.Debug['s'] = 1
symo = int64(ld.Segdata.Fileoff + ld.Segdata.Filelen)
case ld.Hdarwin:
symo = int64(ld.Segdata.Fileoff + uint64(ld.Rnd(int64(ld.Segdata.Filelen), int64(ld.INITRND))) + uint64(machlink))
//.........这里部分代码省略.........
作者：tidatid
项目：g
func adddynrel(s *ld.LSym, r *ld.Reloc) {
targ := r.Sym
ld.Ctxt.Cursym = s
switch r.Type {
default:
if r.Type >= 256 {
ld.Diag("unexpected relocation type %d", r.Type)
return
}
// Handle relocations found in ELF object files.
case 256 + ld.R_X86_64_PC32:
if targ.Type == ld.SDYNIMPORT {
ld.Diag("unexpected R_X86_64_PC32 relocation for dynamic symbol %s", targ.Name)
}
if targ.Type == 0 || targ.Type == ld.SXREF {
ld.Diag("unknown symbol %s in pcrel", targ.Name)
}
r.Type = ld.R_PCREL
r.Add += 4
return
case 256 + ld.R_X86_64_PLT32:
r.Type = ld.R_PCREL
r.Add += 4
if targ.Type == ld.SDYNIMPORT {
addpltsym(targ)
r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0)
r.Add += int64(targ.Plt)
}
return
case 256 + ld.R_X86_64_GOTPCREL:
if targ.Type != ld.SDYNIMPORT {
// have symbol
if r.Off >= 2 && s.P[r.Off-2] == 0x8b {
// turn MOVQ of GOT entry into LEAQ of symbol itself
s.P[r.Off-2] = 0x8d
r.Type = ld.R_PCREL
r.Add += 4
return
}
}
// fall back to using GOT and hope for the best (CMOV*)
// TODO: just needs relocation, no need to put in .dynsym
addgotsym(targ)
r.Type = ld.R_PCREL
r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0)
r.Add += 4
r.Add += int64(targ.Got)
return
case 256 + ld.R_X86_64_64:
if targ.Type == ld.SDYNIMPORT {
ld.Diag("unexpected R_X86_64_64 relocation for dynamic symbol %s", targ.Name)
}
r.Type = ld.R_ADDR
return
// Handle relocations found in Mach-O object files.
case 512 + ld.MACHO_X86_64_RELOC_UNSIGNED*2 + 0,
512 + ld.MACHO_X86_64_RELOC_SIGNED*2 + 0,
512 + ld.MACHO_X86_64_RELOC_BRANCH*2 + 0:
// TODO: What is the difference between all these?
r.Type = ld.R_ADDR
if targ.Type == ld.SDYNIMPORT {
ld.Diag("unexpected reloc for dynamic symbol %s", targ.Name)
}
return
case 512 + ld.MACHO_X86_64_RELOC_BRANCH*2 + 1:
if targ.Type == ld.SDYNIMPORT {
addpltsym(targ)
r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0)
r.Add = int64(targ.Plt)
r.Type = ld.R_PCREL
return
}
fallthrough
// fall through
case 512 + ld.MACHO_X86_64_RELOC_UNSIGNED*2 + 1,
512 + ld.MACHO_X86_64_RELOC_SIGNED*2 + 1,
512 + ld.MACHO_X86_64_RELOC_SIGNED_1*2 + 1,
512 + ld.MACHO_X86_64_RELOC_SIGNED_2*2 + 1,
512 + ld.MACHO_X86_64_RELOC_SIGNED_4*2 + 1:
r.Type = ld.R_PCREL
if targ.Type == ld.SDYNIMPORT {
ld.Diag("unexpected pc-relative reloc for dynamic symbol %s", targ.Name)
}
return
case 512 + ld.MACHO_X86_64_RELOC_GOT_LOAD*2 + 1:
//.........这里部分代码省略.........
作者：tidatid
项目：g
func archinit() {
// getgoextlinkenabled is based on GO_EXTLINK_ENABLED when
// Go was built; see ../../make.bash.
if ld.Linkmode == ld.LinkAuto && obj.Getgoextlinkenabled() == "0" {
ld.Linkmode = ld.LinkInternal
}
if ld.Flag_shared != 0 {
ld.Linkmode = ld.LinkExternal
}
switch ld.HEADTYPE {
default:
if ld.Linkmode == ld.LinkAuto {
ld.Linkmode = ld.LinkInternal
}
if ld.Linkmode == ld.LinkExternal && obj.Getgoextlinkenabled() != "1" {
log.Fatalf("cannot use -linkmode=external with -H %s", ld.Headstr(int(ld.HEADTYPE)))
}
case ld.Hdarwin,
ld.Hdragonfly,
ld.Hfreebsd,
ld.Hlinux,
ld.Hnacl,
ld.Hnetbsd,
ld.Hopenbsd,
ld.Hsolaris,
ld.Hwindows:
break
}
switch ld.HEADTYPE {
default:
ld.Diag("unknown -H option")
ld.Errorexit()
fallthrough
case ld.Hplan9: /* plan 9 */
ld.HEADR = 32 + 8
if ld.INITTEXT == -1 {
ld.INITTEXT = 0x200000 + int64(ld.HEADR)
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 0x200000
}
case ld.Helf: /* elf32 executable */
ld.HEADR = int32(ld.Rnd(52+3*32, 16))
if ld.INITTEXT == -1 {
ld.INITTEXT = 0x80110000
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 4096
}
case ld.Hdarwin: /* apple MACH */
ld.Machoinit()
ld.HEADR = ld.INITIAL_MACHO_HEADR
if ld.INITRND == -1 {
ld.INITRND = 4096
}
if ld.INITTEXT == -1 {
ld.INITTEXT = 4096 + int64(ld.HEADR)
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
case ld.Hlinux, /* elf64 executable */
ld.Hfreebsd, /* freebsd */
ld.Hnetbsd, /* netbsd */
ld.Hopenbsd, /* openbsd */
ld.Hdragonfly, /* dragonfly */
ld.Hsolaris: /* solaris */
ld.Elfinit()
ld.HEADR = ld.ELFRESERVE
if ld.INITTEXT == -1 {
ld.INITTEXT = (1 << 22) + int64(ld.HEADR)
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 4096
}
case ld.Hnacl:
ld.Elfinit()
ld.Debug['w']++ // disable dwarf, which gets confused and is useless anyway
//.........这里部分代码省略.........
