func gentext() {
if !ld.DynlinkingGo() && ld.Buildmode != ld.BuildmodePIE {
return
}
thunkfunc := ld.Linklookup(ld.Ctxt, "__x86.get_pc_thunk.cx", 0)
thunkfunc.Type = obj.STEXT
thunkfunc.Local = true
thunkfunc.Reachable = true
o := func(op ...uint8) {
for _, op1 := range op {
ld.Adduint8(ld.Ctxt, thunkfunc, op1)
}
}
// 8b 0c 24 mov (%esp),%ecx
o(0x8b, 0x0c, 0x24)
// c3 ret
o(0xc3)
if ld.Ctxt.Etextp != nil {
ld.Ctxt.Etextp.Next = thunkfunc
} else {
ld.Ctxt.Textp = thunkfunc
}
ld.Ctxt.Etextp = thunkfunc
}
func archinit(ctxt *ld.Link) {
// 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.Buildmode == ld.BuildmodeCArchive || ld.Buildmode == ld.BuildmodeCShared || ld.DynlinkingGo() {
ld.Linkmode = ld.LinkExternal
}
switch ld.HEADTYPE {
default:
ld.Exitf("unknown -H option: %v", ld.HEADTYPE)
case obj.Hlinux: // s390x ELF
ld.Elfinit(ctxt)
ld.HEADR = ld.ELFRESERVE
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 0x10000 + int64(ld.HEADR)
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 0x10000
}
}
if *ld.FlagDataAddr != 0 && *ld.FlagRound != 0 {
fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(*ld.FlagDataAddr), uint32(*ld.FlagRound))
}
}
func gentext() {
if ld.DynlinkingGo() {
genaddmoduledata()
}
if ld.Linkmode == ld.LinkInternal {
genplt()
}
}
func gentext() {
if !ld.DynlinkingGo() {
return
}
addmoduledata := ld.Linklookup(ld.Ctxt, "runtime.addmoduledata", 0)
if addmoduledata.Type == obj.STEXT {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Attr |= ld.AttrReachable
initfunc := ld.Linklookup(ld.Ctxt, "go.link.addmoduledata", 0)
initfunc.Type = obj.STEXT
initfunc.Attr |= ld.AttrLocal
initfunc.Attr |= ld.AttrReachable
o := func(op uint32) {
ld.Adduint32(ld.Ctxt, initfunc, op)
}
// 0000000000000000 <local.dso_init>:
// 0: 90000000 adrp x0, 0 <runtime.firstmoduledata>
// 0: R_AARCH64_ADR_PREL_PG_HI21 local.moduledata
// 4: 91000000 add x0, x0, #0x0
// 4: R_AARCH64_ADD_ABS_LO12_NC local.moduledata
o(0x90000000)
o(0x91000000)
rel := ld.Addrel(initfunc)
rel.Off = 0
rel.Siz = 8
rel.Sym = ld.Ctxt.Moduledata
rel.Type = obj.R_ADDRARM64
// 8: 14000000 bl 0 <runtime.addmoduledata>
// 8: R_AARCH64_CALL26 runtime.addmoduledata
o(0x14000000)
rel = ld.Addrel(initfunc)
rel.Off = 8
rel.Siz = 4
rel.Sym = ld.Linklookup(ld.Ctxt, "runtime.addmoduledata", 0)
rel.Type = obj.R_CALLARM64 // Really should be R_AARCH64_JUMP26 but doesn't seem to make any difference
if ld.Ctxt.Etextp != nil {
ld.Ctxt.Etextp.Next = initfunc
} else {
ld.Ctxt.Textp = initfunc
}
ld.Ctxt.Etextp = initfunc
initarray_entry := ld.Linklookup(ld.Ctxt, "go.link.addmoduledatainit", 0)
initarray_entry.Attr |= ld.AttrReachable
initarray_entry.Attr |= ld.AttrLocal
initarray_entry.Type = obj.SINITARR
ld.Addaddr(ld.Ctxt, initarray_entry, initfunc)
}
// gentext generates assembly to append the local moduledata to the global
// moduledata linked list at initialization time. This is only done if the runtime
// is in a different module.
//
// <go.link.addmoduledata>:
// larl %r2, <local.moduledata>
// jg <runtime.addmoduledata@plt>
// undef
//
// The job of appending the moduledata is delegated to runtime.addmoduledata.
func gentext(ctxt *ld.Link) {
if !ld.DynlinkingGo() {
return
}
addmoduledata := ld.Linklookup(ctxt, "runtime.addmoduledata", 0)
if addmoduledata.Type == obj.STEXT {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Attr |= ld.AttrReachable
initfunc := ld.Linklookup(ctxt, "go.link.addmoduledata", 0)
initfunc.Type = obj.STEXT
initfunc.Attr |= ld.AttrLocal
initfunc.Attr |= ld.AttrReachable
// larl %r2, <local.moduledata>
ld.Adduint8(ctxt, initfunc, 0xc0)
ld.Adduint8(ctxt, initfunc, 0x20)
lmd := ld.Addrel(initfunc)
lmd.Off = int32(initfunc.Size)
lmd.Siz = 4
lmd.Sym = ctxt.Moduledata
lmd.Type = obj.R_PCREL
lmd.Variant = ld.RV_390_DBL
lmd.Add = 2 + int64(lmd.Siz)
ld.Adduint32(ctxt, initfunc, 0)
// jg <runtime.addmoduledata[@plt]>
ld.Adduint8(ctxt, initfunc, 0xc0)
ld.Adduint8(ctxt, initfunc, 0xf4)
rel := ld.Addrel(initfunc)
rel.Off = int32(initfunc.Size)
rel.Siz = 4
rel.Sym = ld.Linklookup(ctxt, "runtime.addmoduledata", 0)
rel.Type = obj.R_CALL
rel.Variant = ld.RV_390_DBL
rel.Add = 2 + int64(rel.Siz)
ld.Adduint32(ctxt, initfunc, 0)
// undef (for debugging)
ld.Adduint32(ctxt, initfunc, 0)
ctxt.Textp = append(ctxt.Textp, initfunc)
initarray_entry := ld.Linklookup(ctxt, "go.link.addmoduledatainit", 0)
initarray_entry.Attr |= ld.AttrLocal
initarray_entry.Attr |= ld.AttrReachable
initarray_entry.Type = obj.SINITARR
ld.Addaddr(ctxt, initarray_entry, initfunc)
}
func gentext() {
if !ld.DynlinkingGo() {
return
}
addmoduledata := ld.Linklookup(ld.Ctxt, "runtime.addmoduledata", 0)
if addmoduledata.Type == obj.STEXT {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Reachable = true
initfunc := ld.Linklookup(ld.Ctxt, "go.link.addmoduledata", 0)
initfunc.Type = obj.STEXT
initfunc.Local = true
initfunc.Reachable = true
o := func(op uint32) {
ld.Adduint32(ld.Ctxt, initfunc, op)
}
o(0xe59f0004)
o(0xe08f0000)
o(0xeafffffe)
rel := ld.Addrel(initfunc)
rel.Off = 8
rel.Siz = 4
rel.Sym = ld.Linklookup(ld.Ctxt, "runtime.addmoduledata", 0)
rel.Type = obj.R_CALLARM
rel.Add = 0xeafffffe // vomit
o(0x00000000)
rel = ld.Addrel(initfunc)
rel.Off = 12
rel.Siz = 4
rel.Sym = ld.Ctxt.Moduledata
rel.Type = obj.R_PCREL
rel.Add = 4
if ld.Ctxt.Etextp != nil {
ld.Ctxt.Etextp.Next = initfunc
} else {
ld.Ctxt.Textp = initfunc
}
ld.Ctxt.Etextp = initfunc
initarray_entry := ld.Linklookup(ld.Ctxt, "go.link.addmoduledatainit", 0)
initarray_entry.Reachable = true
initarray_entry.Local = true
initarray_entry.Type = obj.SINITARR
ld.Addaddr(ld.Ctxt, initarray_entry, initfunc)
}
func gentext(ctxt *ld.Link) {
if !ld.DynlinkingGo() {
return
}
addmoduledata := ld.Linklookup(ctxt, "runtime.addmoduledata", 0)
if addmoduledata.Type == obj.STEXT {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Attr |= ld.AttrReachable
initfunc := ld.Linklookup(ctxt, "go.link.addmoduledata", 0)
initfunc.Type = obj.STEXT
initfunc.Attr |= ld.AttrLocal
initfunc.Attr |= ld.AttrReachable
o := func(op uint32) {
ld.Adduint32(ctxt, initfunc, op)
}
o(0xe59f0004)
o(0xe08f0000)
o(0xeafffffe)
rel := ld.Addrel(initfunc)
rel.Off = 8
rel.Siz = 4
rel.Sym = ld.Linklookup(ctxt, "runtime.addmoduledata", 0)
rel.Type = obj.R_CALLARM
rel.Add = 0xeafffffe // vomit
o(0x00000000)
rel = ld.Addrel(initfunc)
rel.Off = 12
rel.Siz = 4
rel.Sym = ctxt.Moduledata
rel.Type = obj.R_PCREL
rel.Add = 4
ctxt.Textp = append(ctxt.Textp, initfunc)
initarray_entry := ld.Linklookup(ctxt, "go.link.addmoduledatainit", 0)
initarray_entry.Attr |= ld.AttrReachable
initarray_entry.Attr |= ld.AttrLocal
initarray_entry.Type = obj.SINITARR
ld.Addaddr(ctxt, initarray_entry, initfunc)
}
func gentext() {
if !ld.DynlinkingGo() {
return
}
addmoduledata := ld.Linklookup(ld.Ctxt, "runtime.addmoduledata", 0)
if addmoduledata.Type == obj.STEXT {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Reachable = true
initfunc := ld.Linklookup(ld.Ctxt, "go.link.addmoduledata", 0)
initfunc.Type = obj.STEXT
initfunc.Local = true
initfunc.Reachable = true
o := func(op ...uint8) {
for _, op1 := range op {
ld.Adduint8(ld.Ctxt, initfunc, op1)
}
}
// 0000000000000000 <local.dso_init>:
// 0: 48 8d 3d 00 00 00 00 lea 0x0(%rip),%rdi # 7 <local.dso_init+0x7>
// 3: R_X86_64_PC32 runtime.firstmoduledata-0x4
o(0x48, 0x8d, 0x3d)
ld.Addpcrelplus(ld.Ctxt, initfunc, ld.Ctxt.Moduledata, 0)
// 7: e8 00 00 00 00 callq c <local.dso_init+0xc>
// 8: R_X86_64_PLT32 runtime.addmoduledata-0x4
o(0xe8)
Addcall(ld.Ctxt, initfunc, addmoduledata)
// c: c3 retq
o(0xc3)
if ld.Ctxt.Etextp != nil {
ld.Ctxt.Etextp.Next = initfunc
} else {
ld.Ctxt.Textp = initfunc
}
ld.Ctxt.Etextp = initfunc
initarray_entry := ld.Linklookup(ld.Ctxt, "go.link.addmoduledatainit", 0)
initarray_entry.Reachable = true
initarray_entry.Local = true
initarray_entry.Type = obj.SINITARR
ld.Addaddr(ld.Ctxt, initarray_entry, initfunc)
}
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.Buildmode == ld.BuildmodeCArchive || ld.Buildmode == ld.BuildmodeCShared || ld.DynlinkingGo() {
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 obj.Hlinux,
obj.Hfreebsd,
obj.Hnacl,
obj.Hdarwin:
break
}
switch ld.HEADTYPE {
default:
ld.Exitf("unknown -H option: %v", ld.HEADTYPE)
case obj.Hplan9: /* plan 9 */
ld.HEADR = 32
if ld.INITTEXT == -1 {
ld.INITTEXT = 4128
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 4096
}
case obj.Hlinux, /* arm elf */
obj.Hfreebsd,
obj.Hnetbsd,
obj.Hopenbsd:
ld.Debug['d'] = 0
// with dynamic linking
ld.Elfinit()
ld.HEADR = ld.ELFRESERVE
if ld.INITTEXT == -1 {
ld.INITTEXT = 0x10000 + int64(ld.HEADR)
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 4096
}
case obj.Hnacl:
ld.Elfinit()
ld.HEADR = 0x10000
ld.Funcalign = 16
if ld.INITTEXT == -1 {
ld.INITTEXT = 0x20000
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 0x10000
}
case obj.Hdarwin: /* apple MACH */
ld.Debug['w'] = 1 // disable DWARF generation
ld.Machoinit()
ld.HEADR = ld.INITIAL_MACHO_HEADR
if ld.INITTEXT == -1 {
ld.INITTEXT = 4096 + int64(ld.HEADR)
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 4096
}
}
if ld.INITDAT != 0 && ld.INITRND != 0 {
fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(ld.INITDAT), uint32(ld.INITRND))
}
}
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int {
if ld.Linkmode == ld.LinkExternal {
switch r.Type {
default:
return -1
case obj.R_ARM64_GOTPCREL:
var o1, o2 uint32
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
o1 = uint32(*val >> 32)
o2 = uint32(*val)
} else {
o1 = uint32(*val)
o2 = uint32(*val >> 32)
}
// Any relocation against a function symbol is redirected to
// be against a local symbol instead (see putelfsym in
// symtab.go) but unfortunately the system linker was buggy
// when confronted with a R_AARCH64_ADR_GOT_PAGE relocation
// against a local symbol until May 2015
// (https://sourceware.org/bugzilla/show_bug.cgi?id=18270). So
// we convert the adrp; ld64 + R_ARM64_GOTPCREL into adrp;
// add + R_ADDRARM64.
if !(r.Sym.Version != 0 || (r.Sym.Type&obj.SHIDDEN != 0) || r.Sym.Attr.Local()) && r.Sym.Type == obj.STEXT && ld.DynlinkingGo() {
if o2&0xffc00000 != 0xf9400000 {
ld.Ctxt.Diag("R_ARM64_GOTPCREL against unexpected instruction %x", o2)
}
o2 = 0x91000000 | (o2 & 0x000003ff)
r.Type = obj.R_ADDRARM64
}
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
*val = int64(o1)<<32 | int64(o2)
} else {
*val = int64(o2)<<32 | int64(o1)
}
fallthrough
case obj.R_ADDRARM64:
r.Done = 0
// set up addend for eventual relocation via outer symbol.
rs := r.Sym
r.Xadd = r.Add
for rs.Outer != nil {
r.Xadd += ld.Symaddr(rs) - ld.Symaddr(rs.Outer)
rs = rs.Outer
}
if rs.Type != obj.SHOSTOBJ && rs.Type != obj.SDYNIMPORT && rs.Sect == nil {
ld.Diag("missing section for %s", rs.Name)
}
r.Xsym = rs
// Note: ld64 currently has a bug that any non-zero addend for BR26 relocation
// will make the linking fail because it thinks the code is not PIC even though
// the BR26 relocation should be fully resolved at link time.
// That is the reason why the next if block is disabled. When the bug in ld64
// is fixed, we can enable this block and also enable duff's device in cmd/7g.
if false && ld.HEADTYPE == obj.Hdarwin {
var o0, o1 uint32
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
o0 = uint32(*val >> 32)
o1 = uint32(*val)
} else {
o0 = uint32(*val)
o1 = uint32(*val >> 32)
}
// Mach-O wants the addend to be encoded in the instruction
// Note that although Mach-O supports ARM64_RELOC_ADDEND, it
// can only encode 24-bit of signed addend, but the instructions
// supports 33-bit of signed addend, so we always encode the
// addend in place.
o0 |= (uint32((r.Xadd>>12)&3) << 29) | (uint32((r.Xadd>>12>>2)&0x7ffff) << 5)
o1 |= uint32(r.Xadd&0xfff) << 10
r.Xadd = 0
// when laid out, the instruction order must always be o1, o2.
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
*val = int64(o0)<<32 | int64(o1)
} else {
*val = int64(o1)<<32 | int64(o0)
}
}
return 0
case obj.R_CALLARM64,
obj.R_ARM64_TLS_LE,
obj.R_ARM64_TLS_IE:
r.Done = 0
r.Xsym = r.Sym
r.Xadd = r.Add
return 0
}
}
switch r.Type {
case obj.R_CONST:
*val = r.Add
return 0
case obj.R_GOTOFF:
*val = ld.Symaddr(r.Sym) + r.Add - ld.Symaddr(ld.Linklookup(ld.Ctxt, ".got", 0))
return 0
case obj.R_ADDRARM64:
t := ld.Symaddr(r.Sym) + r.Add - ((s.Value + int64(r.Off)) &^ 0xfff)
if t >= 1<<32 || t < -1<<32 {
ld.Diag("program too large, address relocation distance = %d", t)
}
var o0, o1 uint32
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
o0 = uint32(*val >> 32)
o1 = uint32(*val)
} else {
o0 = uint32(*val)
o1 = uint32(*val >> 32)
}
o0 |= (uint32((t>>12)&3) << 29) | (uint32((t>>12>>2)&0x7ffff) << 5)
o1 |= uint32(t&0xfff) << 10
// when laid out, the instruction order must always be o1, o2.
if ld.Ctxt.Arch.ByteOrder == binary.BigEndian {
*val = int64(o0)<<32 | int64(o1)
} else {
*val = int64(o1)<<32 | int64(o0)
}
return 0
case obj.R_ARM64_TLS_LE:
r.Done = 0
if ld.HEADTYPE != obj.Hlinux {
ld.Diag("TLS reloc on unsupported OS %s", ld.Headstr(int(ld.HEADTYPE)))
}
// The TCB is two pointers. This is not documented anywhere, but is
// de facto part of the ABI.
v := r.Sym.Value + int64(2*ld.Thearch.Ptrsize)
if v < 0 || v >= 32678 {
ld.Diag("TLS offset out of range %d", v)
}
*val |= v << 5
return 0
case obj.R_CALLARM64:
t := (ld.Symaddr(r.Sym) + r.Add) - (s.Value + int64(r.Off))
if t >= 1<<27 || t < -1<<27 {
ld.Diag("program too large, call relocation distance = %d", t)
}
*val |= (t >> 2) & 0x03ffffff
return 0
}
return -1
}
func elfreloc1(r *ld.Reloc, sectoff int64) int {
ld.Thearch.Vput(uint64(sectoff))
elfsym := r.Xsym.ElfsymForReloc()
switch r.Type {
default:
return -1
case obj.R_ADDR:
if r.Siz == 4 {
ld.Thearch.Vput(ld.R_X86_64_32 | uint64(elfsym)<<32)
} else if r.Siz == 8 {
ld.Thearch.Vput(ld.R_X86_64_64 | uint64(elfsym)<<32)
} else {
return -1
}
case obj.R_TLS_LE:
if r.Siz == 4 {
ld.Thearch.Vput(ld.R_X86_64_TPOFF32 | uint64(elfsym)<<32)
} else {
return -1
}
case obj.R_TLS_IE:
if r.Siz == 4 {
ld.Thearch.Vput(ld.R_X86_64_GOTTPOFF | uint64(elfsym)<<32)
} else {
return -1
}
case obj.R_CALL:
if r.Siz == 4 {
if r.Xsym.Type == obj.SDYNIMPORT {
if ld.DynlinkingGo() {
ld.Thearch.Vput(ld.R_X86_64_PLT32 | uint64(elfsym)<<32)
} else {
ld.Thearch.Vput(ld.R_X86_64_GOTPCREL | uint64(elfsym)<<32)
}
} else {
ld.Thearch.Vput(ld.R_X86_64_PC32 | uint64(elfsym)<<32)
}
} else {
return -1
}
case obj.R_PCREL:
if r.Siz == 4 {
if r.Xsym.Type == obj.SDYNIMPORT && r.Xsym.ElfType == elf.STT_FUNC {
ld.Thearch.Vput(ld.R_X86_64_PLT32 | uint64(elfsym)<<32)
} else {
ld.Thearch.Vput(ld.R_X86_64_PC32 | uint64(elfsym)<<32)
}
} else {
return -1
}
case obj.R_GOTPCREL:
if r.Siz == 4 {
ld.Thearch.Vput(ld.R_X86_64_GOTPCREL | uint64(elfsym)<<32)
} else {
return -1
}
}
ld.Thearch.Vput(uint64(r.Xadd))
return 0
}
func gentext() {
if !ld.DynlinkingGo() && ld.Buildmode != ld.BuildmodePIE && ld.Buildmode != ld.BuildmodeCShared {
return
}
thunkfunc := ld.Linklookup(ld.Ctxt, "__x86.get_pc_thunk.cx", 0)
thunkfunc.Type = obj.STEXT
thunkfunc.Local = true
thunkfunc.Reachable = true
o := func(op ...uint8) {
for _, op1 := range op {
ld.Adduint8(ld.Ctxt, thunkfunc, op1)
}
}
// 8b 0c 24 mov (%esp),%ecx
o(0x8b, 0x0c, 0x24)
// c3 ret
o(0xc3)
if ld.Ctxt.Etextp != nil {
ld.Ctxt.Etextp.Next = thunkfunc
} else {
ld.Ctxt.Textp = thunkfunc
}
ld.Ctxt.Etextp = thunkfunc
addmoduledata := ld.Linklookup(ld.Ctxt, "runtime.addmoduledata", 0)
if addmoduledata.Type == obj.STEXT {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Reachable = true
initfunc := ld.Linklookup(ld.Ctxt, "go.link.addmoduledata", 0)
initfunc.Type = obj.STEXT
initfunc.Local = true
initfunc.Reachable = true
o = func(op ...uint8) {
for _, op1 := range op {
ld.Adduint8(ld.Ctxt, initfunc, op1)
}
}
// go.link.addmoduledata:
// 53 push %ebx
// e8 00 00 00 00 call __x86.get_pc_thunk.cx + R_CALL __x86.get_pc_thunk.cx
// 8d 81 00 00 00 00 lea 0x0(%ecx), %eax + R_PCREL ld.Ctxt.Moduledata
// 8d 99 00 00 00 00 lea 0x0(%ecx), %ebx + R_GOTPC _GLOBAL_OFFSET_TABLE_
// e8 00 00 00 00 call runtime.addmoduledata@plt + R_CALL runtime.addmoduledata
// 5b pop %ebx
// c3 ret
o(0x53)
o(0xe8)
addcall(ld.Ctxt, initfunc, ld.Linklookup(ld.Ctxt, "__x86.get_pc_thunk.cx", 0))
o(0x8d, 0x81)
ld.Addpcrelplus(ld.Ctxt, initfunc, ld.Ctxt.Moduledata, 6)
o(0x8d, 0x99)
i := initfunc.Size
initfunc.Size += 4
ld.Symgrow(ld.Ctxt, initfunc, initfunc.Size)
r := ld.Addrel(initfunc)
r.Sym = ld.Linklookup(ld.Ctxt, "_GLOBAL_OFFSET_TABLE_", 0)
r.Off = int32(i)
r.Type = obj.R_PCREL
r.Add = 12
r.Siz = 4
o(0xe8)
addcall(ld.Ctxt, initfunc, addmoduledata)
o(0x5b)
o(0xc3)
ld.Ctxt.Etextp.Next = initfunc
ld.Ctxt.Etextp = initfunc
initarray_entry := ld.Linklookup(ld.Ctxt, "go.link.addmoduledatainit", 0)
initarray_entry.Reachable = true
initarray_entry.Local = true
initarray_entry.Type = obj.SINITARR
ld.Addaddr(ld.Ctxt, initarray_entry, initfunc)
}
func gentext(ctxt *ld.Link) {
if !ld.DynlinkingGo() && ld.Buildmode != ld.BuildmodePIE && ld.Buildmode != ld.BuildmodeCShared {
return
}
// Generate little thunks that load the PC of the next instruction into a register.
for _, r := range [...]struct {
name string
num uint8
}{
{"ax", 0},
{"cx", 1},
{"dx", 2},
{"bx", 3},
// sp
{"bp", 5},
{"si", 6},
{"di", 7},
} {
thunkfunc := ld.Linklookup(ctxt, "__x86.get_pc_thunk."+r.name, 0)
thunkfunc.Type = obj.STEXT
thunkfunc.Attr |= ld.AttrLocal
thunkfunc.Attr |= ld.AttrReachable //TODO: remove?
o := func(op ...uint8) {
for _, op1 := range op {
ld.Adduint8(ctxt, thunkfunc, op1)
}
}
// 8b 04 24 mov (%esp),%eax
// Destination register is in bits 3-5 of the middle byte, so add that in.
o(0x8b, 0x04+r.num<<3, 0x24)
// c3 ret
o(0xc3)
ctxt.Textp = append(ctxt.Textp, thunkfunc)
}
addmoduledata := ld.Linklookup(ctxt, "runtime.addmoduledata", 0)
if addmoduledata.Type == obj.STEXT {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Attr |= ld.AttrReachable
initfunc := ld.Linklookup(ctxt, "go.link.addmoduledata", 0)
initfunc.Type = obj.STEXT
initfunc.Attr |= ld.AttrLocal
initfunc.Attr |= ld.AttrReachable
o := func(op ...uint8) {
for _, op1 := range op {
ld.Adduint8(ctxt, initfunc, op1)
}
}
// go.link.addmoduledata:
// 53 push %ebx
// e8 00 00 00 00 call __x86.get_pc_thunk.cx + R_CALL __x86.get_pc_thunk.cx
// 8d 81 00 00 00 00 lea 0x0(%ecx), %eax + R_PCREL ctxt.Moduledata
// 8d 99 00 00 00 00 lea 0x0(%ecx), %ebx + R_GOTPC _GLOBAL_OFFSET_TABLE_
// e8 00 00 00 00 call runtime.addmoduledata@plt + R_CALL runtime.addmoduledata
// 5b pop %ebx
// c3 ret
o(0x53)
o(0xe8)
addcall(ctxt, initfunc, ld.Linklookup(ctxt, "__x86.get_pc_thunk.cx", 0))
o(0x8d, 0x81)
ld.Addpcrelplus(ctxt, initfunc, ctxt.Moduledata, 6)
o(0x8d, 0x99)
i := initfunc.Size
initfunc.Size += 4
ld.Symgrow(ctxt, initfunc, initfunc.Size)
r := ld.Addrel(initfunc)
r.Sym = ld.Linklookup(ctxt, "_GLOBAL_OFFSET_TABLE_", 0)
r.Off = int32(i)
r.Type = obj.R_PCREL
r.Add = 12
r.Siz = 4
o(0xe8)
addcall(ctxt, initfunc, addmoduledata)
o(0x5b)
o(0xc3)
ctxt.Textp = append(ctxt.Textp, initfunc)
initarray_entry := ld.Linklookup(ctxt, "go.link.addmoduledatainit", 0)
initarray_entry.Attr |= ld.AttrReachable
initarray_entry.Attr |= ld.AttrLocal
initarray_entry.Type = obj.SINITARR
ld.Addaddr(ctxt, initarray_entry, initfunc)
}
func archinit(ctxt *ld.Link) {
// 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.Buildmode == ld.BuildmodeCShared || ld.Buildmode == ld.BuildmodePIE || ld.DynlinkingGo() {
ld.Linkmode = ld.LinkExternal
got := ld.Linklookup(ctxt, "_GLOBAL_OFFSET_TABLE_", 0)
got.Type = obj.SDYNIMPORT
got.Attr |= ld.AttrReachable
}
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 obj.Hdarwin,
obj.Hfreebsd,
obj.Hlinux,
obj.Hnetbsd,
obj.Hopenbsd,
obj.Hwindows:
break
}
switch ld.HEADTYPE {
default:
ld.Exitf("unknown -H option: %v", ld.HEADTYPE)
case obj.Hplan9: /* plan 9 */
ld.HEADR = 32
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 4096 + 32
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 4096
}
case obj.Hdarwin: /* apple MACH */
ld.Machoinit()
ld.HEADR = ld.INITIAL_MACHO_HEADR
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 4096 + int64(ld.HEADR)
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 4096
}
case obj.Hlinux, /* elf32 executable */
obj.Hfreebsd,
obj.Hnetbsd,
obj.Hopenbsd:
ld.Elfinit(ctxt)
ld.HEADR = ld.ELFRESERVE
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 0x08048000 + int64(ld.HEADR)
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 4096
}
case obj.Hnacl:
ld.Elfinit(ctxt)
ld.HEADR = 0x10000
ld.Funcalign = 32
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 0x20000
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 0x10000
}
case obj.Hwindows: /* PE executable */
ld.Peinit(ctxt)
ld.HEADR = ld.PEFILEHEADR
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = ld.PEBASE + int64(ld.PESECTHEADR)
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = ld.PESECTALIGN
}
}
if *ld.FlagDataAddr != 0 && *ld.FlagRound != 0 {
fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(*ld.FlagDataAddr), uint32(*ld.FlagRound))
}
}
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.Buildmode == ld.BuildmodeCArchive || ld.Buildmode == ld.BuildmodeCShared || ld.DynlinkingGo() {
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 obj.Hdarwin,
obj.Hdragonfly,
obj.Hhaiku,
obj.Hfreebsd,
obj.Hlinux,
obj.Hnacl,
obj.Hnetbsd,
obj.Hopenbsd,
obj.Hsolaris,
obj.Hwindows:
break
}
switch ld.HEADTYPE {
default:
ld.Exitf("unknown -H option: %v", ld.HEADTYPE)
case obj.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 obj.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 obj.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 obj.Hlinux, /* elf64 executable */
obj.Hfreebsd, /* freebsd */
obj.Hhaiku, /* haiku */
obj.Hnetbsd, /* netbsd */
obj.Hopenbsd, /* openbsd */
obj.Hdragonfly, /* dragonfly */
obj.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 obj.Hnacl:
ld.Elfinit()
ld.Debug['w']++ // disable dwarf, which gets confused and is useless anyway
ld.HEADR = 0x10000
ld.Funcalign = 32
if ld.INITTEXT == -1 {
ld.INITTEXT = 0x20000
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = 0x10000
}
case obj.Hwindows: /* PE executable */
ld.Peinit()
ld.HEADR = ld.PEFILEHEADR
if ld.INITTEXT == -1 {
ld.INITTEXT = ld.PEBASE + int64(ld.PESECTHEADR)
}
if ld.INITDAT == -1 {
ld.INITDAT = 0
}
if ld.INITRND == -1 {
ld.INITRND = ld.PESECTALIGN
}
}
if ld.INITDAT != 0 && ld.INITRND != 0 {
fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(ld.INITDAT), uint32(ld.INITRND))
}
}
func archinit(ctxt *ld.Link) {
// 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
}
// Darwin/arm64 only supports external linking
if ld.HEADTYPE == obj.Hdarwin {
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 obj.Hlinux, obj.Hdarwin:
break
}
if ld.Buildmode == ld.BuildmodeCShared || ld.DynlinkingGo() {
ld.Linkmode = ld.LinkExternal
}
switch ld.HEADTYPE {
default:
ld.Exitf("unknown -H option: %v", ld.HEADTYPE)
case obj.Hplan9: /* plan 9 */
ld.HEADR = 32
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 4128
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 4096
}
case obj.Hlinux: /* arm64 elf */
ld.Elfinit(ctxt)
ld.HEADR = ld.ELFRESERVE
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 0x10000 + int64(ld.HEADR)
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 0x10000
}
case obj.Hdarwin: /* apple MACH */
*ld.FlagW = true // disable DWARF generation
ld.Machoinit()
ld.HEADR = ld.INITIAL_MACHO_HEADR
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 4096 + int64(ld.HEADR)
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 4096
}
case obj.Hnacl:
ld.Elfinit(ctxt)
ld.HEADR = 0x10000
ld.Funcalign = 16
if *ld.FlagTextAddr == -1 {
*ld.FlagTextAddr = 0x20000
}
if *ld.FlagDataAddr == -1 {
*ld.FlagDataAddr = 0
}
if *ld.FlagRound == -1 {
*ld.FlagRound = 0x10000
}
}
if *ld.FlagDataAddr != 0 && *ld.FlagRound != 0 {
fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(*ld.FlagDataAddr), uint32(*ld.FlagRound))
}
}