func elfsetupplt() { plt := ld.Linklookup(ld.Ctxt, ".plt", 0) got := ld.Linklookup(ld.Ctxt, ".got.plt", 0) if plt.Size == 0 { // pushl got+4 ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x35) ld.Addaddrplus(ld.Ctxt, plt, got, 4) // jmp *got+8 ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x25) ld.Addaddrplus(ld.Ctxt, plt, got, 8) // zero pad ld.Adduint32(ld.Ctxt, plt, 0) // assume got->size == 0 too ld.Addaddrplus(ld.Ctxt, got, ld.Linklookup(ld.Ctxt, ".dynamic", 0), 0) ld.Adduint32(ld.Ctxt, got, 0) ld.Adduint32(ld.Ctxt, got, 0) } }
func elfsetupplt() { plt := ld.Linklookup(ld.Ctxt, ".plt", 0) got := ld.Linklookup(ld.Ctxt, ".got.plt", 0) if plt.Size == 0 { // str lr, [sp, #-4]! ld.Adduint32(ld.Ctxt, plt, 0xe52de004) // ldr lr, [pc, #4] ld.Adduint32(ld.Ctxt, plt, 0xe59fe004) // add lr, pc, lr ld.Adduint32(ld.Ctxt, plt, 0xe08fe00e) // ldr pc, [lr, #8]! ld.Adduint32(ld.Ctxt, plt, 0xe5bef008) // .word &GLOBAL_OFFSET_TABLE[0] - . ld.Addpcrelplus(ld.Ctxt, plt, got, 4) // the first .plt entry requires 3 .plt.got entries ld.Adduint32(ld.Ctxt, got, 0) ld.Adduint32(ld.Ctxt, got, 0) ld.Adduint32(ld.Ctxt, got, 0) } }
func elfsetupplt() { plt := ld.Linklookup(ld.Ctxt, ".plt", 0) got := ld.Linklookup(ld.Ctxt, ".got.plt", 0) if plt.Size == 0 { // pushq got+8(IP) ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x35) ld.Addpcrelplus(ld.Ctxt, plt, got, 8) // jmpq got+16(IP) ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x25) ld.Addpcrelplus(ld.Ctxt, plt, got, 16) // nopl 0(AX) ld.Adduint32(ld.Ctxt, plt, 0x00401f0f) // assume got->size == 0 too ld.Addaddrplus(ld.Ctxt, got, ld.Linklookup(ld.Ctxt, ".dynamic", 0), 0) ld.Adduint64(ld.Ctxt, got, 0) ld.Adduint64(ld.Ctxt, got, 0) } }
// Generate the glink resolver stub if necessary and return the .glink section func ensureglinkresolver() *ld.LSym { glink := ld.Linklookup(ld.Ctxt, ".glink", 0) if glink.Size != 0 { return glink } // This is essentially the resolver from the ppc64 ELF ABI. // At entry, r12 holds the address of the symbol resolver stub // for the target routine and the argument registers hold the // arguments for the target routine. // // This stub is PIC, so first get the PC of label 1 into r11. // Other things will be relative to this. ld.Adduint32(ld.Ctxt, glink, 0x7c0802a6) // mflr r0 ld.Adduint32(ld.Ctxt, glink, 0x429f0005) // bcl 20,31,1f ld.Adduint32(ld.Ctxt, glink, 0x7d6802a6) // 1: mflr r11 ld.Adduint32(ld.Ctxt, glink, 0x7c0803a6) // mtlf r0 // Compute the .plt array index from the entry point address. // Because this is PIC, everything is relative to label 1b (in // r11): // r0 = ((r12 - r11) - (res_0 - r11)) / 4 = (r12 - res_0) / 4 ld.Adduint32(ld.Ctxt, glink, 0x3800ffd0) // li r0,-(res_0-1b)=-48 ld.Adduint32(ld.Ctxt, glink, 0x7c006214) // add r0,r0,r12 ld.Adduint32(ld.Ctxt, glink, 0x7c0b0050) // sub r0,r0,r11 ld.Adduint32(ld.Ctxt, glink, 0x7800f082) // srdi r0,r0,2 // r11 = address of the first byte of the PLT r := ld.Addrel(glink) r.Off = int32(glink.Size) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Siz = 8 r.Type = obj.R_ADDRPOWER ld.Adduint32(ld.Ctxt, glink, 0x3d600000) // addis r11,0,.plt@ha ld.Adduint32(ld.Ctxt, glink, 0x396b0000) // addi r11,r11,.plt@l // Load r12 = dynamic resolver address and r11 = DSO // identifier from the first two doublewords of the PLT. ld.Adduint32(ld.Ctxt, glink, 0xe98b0000) // ld r12,0(r11) ld.Adduint32(ld.Ctxt, glink, 0xe96b0008) // ld r11,8(r11) // Jump to the dynamic resolver ld.Adduint32(ld.Ctxt, glink, 0x7d8903a6) // mtctr r12 ld.Adduint32(ld.Ctxt, glink, 0x4e800420) // bctr // The symbol resolvers must immediately follow. // res_0: // Add DT_PPC64_GLINK .dynamic entry, which points to 32 bytes // before the first symbol resolver stub. s := ld.Linklookup(ld.Ctxt, ".dynamic", 0) ld.Elfwritedynentsymplus(s, ld.DT_PPC64_GLINK, glink, glink.Size-32) return glink }
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) } // 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.Reachable = true initarray_entry.Local = true initarray_entry.Type = obj.SINITARR ld.Addaddr(ld.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 addgotsym(ctxt *ld.Link, s *ld.LSym) { if s.Got >= 0 { return } ld.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") } }
func addpltsym(ctxt *ld.Link, s *ld.LSym) { if s.Plt >= 0 { return } ld.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 = obj.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") } }
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 elfsetupplt() { plt := ld.Linklookup(ld.Ctxt, ".plt", 0) if plt.Size == 0 { // The dynamic linker stores the address of the // dynamic resolver and the DSO identifier in the two // doublewords at the beginning of the .plt section // before the PLT array. Reserve space for these. plt.Size = 16 } }
func addgotsym(s *ld.LSym) { if s.Got >= 0 { return } ld.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 == obj.Hdarwin { ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.got", 0), uint32(s.Dynid)) } else { ld.Diag("addgotsym: unsupported binary format") } }
func addpltsym(ctxt *ld.Link, s *ld.LSym) { if s.Plt >= 0 { return } ld.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 == obj.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") } }
func addpltsym(ctxt *ld.Link, s *ld.LSym) { if s.Plt >= 0 { return } ld.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() } // .got entry s.Got = int32(got.Size) // In theory, all GOT should point to the first PLT entry, // Linux/ARM's dynamic linker will do that for us, but FreeBSD/ARM's // dynamic linker won't, so we'd better do it ourselves. ld.Addaddrplus(ctxt, got, plt, 0) // .plt entry, this depends on the .got entry s.Plt = int32(plt.Size) addpltreloc(ctxt, plt, got, s, obj.R_PLT0) // add lr, pc, #0xXX00000 addpltreloc(ctxt, plt, got, s, obj.R_PLT1) // add lr, lr, #0xYY000 addpltreloc(ctxt, plt, got, s, obj.R_PLT2) // ldr pc, [lr, #0xZZZ]! // rel ld.Addaddrplus(ctxt, rel, got, int64(s.Got)) ld.Adduint32(ctxt, rel, ld.ELF32_R_INFO(uint32(s.Dynid), ld.R_ARM_JUMP_SLOT)) } else { ld.Diag("addpltsym: unsupported binary format") } }
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") } }
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int { if ld.Linkmode == ld.LinkExternal { return -1 } 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 } return -1 }
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int { if ld.Linkmode == ld.LinkExternal { return -1 } 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_ADDRMIPS: t := ld.Symaddr(r.Sym) + r.Add if t >= 1<<32 || t < -1<<32 { ld.Diag("program too large, address relocation = %v", t) } // the first instruction is always at the lower address, this is endian neutral; // but note that o1 and o2 should still use the target endian. o1 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off:]) o2 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off+4:]) o1 = o1&0xffff0000 | uint32(t>>16)&0xffff o2 = o2&0xffff0000 | uint32(t)&0xffff // when laid out, the instruction order must always be o1, o2. if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { *val = int64(o1)<<32 | int64(o2) } else { *val = int64(o2)<<32 | int64(o1) } return 0 case obj.R_CALLMIPS, obj.R_JMPMIPS: // Low 26 bits = (S + A) >> 2 t := ld.Symaddr(r.Sym) + r.Add o1 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off:]) *val = int64(o1&0xfc000000 | uint32(t>>2)&^0xfc000000) return 0 } return -1 }
// Construct a call stub in stub that calls symbol targ via its PLT // entry. func gencallstub(abicase int, stub *ld.LSym, targ *ld.LSym) { if abicase != 1 { // If we see R_PPC64_TOCSAVE or R_PPC64_REL24_NOTOC // relocations, we'll need to implement cases 2 and 3. log.Fatalf("gencallstub only implements case 1 calls") } plt := ld.Linklookup(ld.Ctxt, ".plt", 0) stub.Type = obj.STEXT // Save TOC pointer in TOC save slot ld.Adduint32(ld.Ctxt, stub, 0xf8410018) // std r2,24(r1) // Load the function pointer from the PLT. r := ld.Addrel(stub) r.Off = int32(stub.Size) r.Sym = plt r.Add = int64(targ.Plt) r.Siz = 2 if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { r.Off += int32(r.Siz) } r.Type = obj.R_POWER_TOC r.Variant = ld.RV_POWER_HA ld.Adduint32(ld.Ctxt, stub, 0x3d820000) // addis r12,r2,targ@plt@toc@ha r = ld.Addrel(stub) r.Off = int32(stub.Size) r.Sym = plt r.Add = int64(targ.Plt) r.Siz = 2 if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { r.Off += int32(r.Siz) } r.Type = obj.R_POWER_TOC r.Variant = ld.RV_POWER_LO ld.Adduint32(ld.Ctxt, stub, 0xe98c0000) // ld r12,targ@plt@toc@l(r12) // Jump to the loaded pointer ld.Adduint32(ld.Ctxt, stub, 0x7d8903a6) // mtctr r12 ld.Adduint32(ld.Ctxt, stub, 0x4e800420) // bctr }
func addpltsym(s *ld.LSym) { if s.Plt >= 0 { return } ld.Adddynsym(ld.Ctxt, s) if ld.Iself { plt := ld.Linklookup(ld.Ctxt, ".plt", 0) got := ld.Linklookup(ld.Ctxt, ".got.plt", 0) rela := ld.Linklookup(ld.Ctxt, ".rela.plt", 0) if plt.Size == 0 { elfsetupplt() } // jmpq *got+size(IP) ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x25) ld.Addpcrelplus(ld.Ctxt, plt, got, got.Size) // add to got: pointer to current pos in plt ld.Addaddrplus(ld.Ctxt, got, plt, plt.Size) // pushq $x ld.Adduint8(ld.Ctxt, plt, 0x68) ld.Adduint32(ld.Ctxt, plt, uint32((got.Size-24-8)/8)) // jmpq .plt ld.Adduint8(ld.Ctxt, plt, 0xe9) ld.Adduint32(ld.Ctxt, plt, uint32(-(plt.Size + 4))) // rela ld.Addaddrplus(ld.Ctxt, rela, got, got.Size-8) ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(s.Dynid), ld.R_X86_64_JMP_SLOT)) ld.Adduint64(ld.Ctxt, rela, 0) s.Plt = int32(plt.Size - 16) } else if ld.HEADTYPE == obj.Hdarwin { // To do lazy symbol lookup right, we're supposed // to tell the dynamic loader which library each // symbol comes from and format the link info // section just so. I'm too lazy (ha!) to do that // so for now we'll just use non-lazy pointers, // which don't need to be told which library to use. // // http://networkpx.blogspot.com/2009/09/about-lcdyldinfoonly-command.html // has details about what we're avoiding. addgotsym(s) plt := ld.Linklookup(ld.Ctxt, ".plt", 0) ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.plt", 0), uint32(s.Dynid)) // jmpq *got+size(IP) s.Plt = int32(plt.Size) ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x25) ld.Addpcrelplus(ld.Ctxt, plt, ld.Linklookup(ld.Ctxt, ".got", 0), int64(s.Got)) } else { ld.Diag("addpltsym: unsupported binary format") } }
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_POWER_TLS, obj.R_POWER_TLS_LE, obj.R_POWER_TLS_IE: r.Done = 0 // check Outer is nil, Type is TLSBSS? r.Xadd = r.Add r.Xsym = r.Sym return 0 case obj.R_ADDRPOWER, obj.R_ADDRPOWER_DS, obj.R_ADDRPOWER_TOCREL, obj.R_ADDRPOWER_TOCREL_DS, obj.R_ADDRPOWER_GOT, obj.R_ADDRPOWER_PCREL: 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 return 0 case obj.R_CALLPOWER: 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_ADDRPOWER, obj.R_ADDRPOWER_DS: return archrelocaddr(r, s, val) case obj.R_CALLPOWER: // Bits 6 through 29 = (S + A - P) >> 2 t := ld.Symaddr(r.Sym) + r.Add - (s.Value + int64(r.Off)) if t&3 != 0 { ld.Ctxt.Diag("relocation for %s+%d is not aligned: %d", r.Sym.Name, r.Off, t) } if int64(int32(t<<6)>>6) != t { // TODO(austin) This can happen if text > 32M. // Add a call trampoline to .text in that case. ld.Ctxt.Diag("relocation for %s+%d is too big: %d", r.Sym.Name, r.Off, t) } *val |= int64(uint32(t) &^ 0xfc000003) return 0 case obj.R_POWER_TOC: // S + A - .TOC. *val = ld.Symaddr(r.Sym) + r.Add - symtoc(s) return 0 case obj.R_POWER_TLS_LE: // The thread pointer points 0x7000 bytes after the start of the the // thread local storage area as documented in section "3.7.2 TLS // Runtime Handling" of "Power Architecture 64-Bit ELF V2 ABI // Specification". v := r.Sym.Value - 0x7000 if int64(int16(v)) != v { ld.Diag("TLS offset out of range %d", v) } *val = (*val &^ 0xffff) | (v & 0xffff) return 0 } return -1 }
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 == obj.SDYNIMPORT { ld.Diag("unexpected R_X86_64_PC32 relocation for dynamic symbol %s", targ.Name) } if targ.Type == 0 || targ.Type == obj.SXREF { ld.Diag("unknown symbol %s in pcrel", targ.Name) } r.Type = obj.R_PCREL r.Add += 4 return case 256 + ld.R_X86_64_PLT32: r.Type = obj.R_PCREL r.Add += 4 if targ.Type == obj.SDYNIMPORT { addpltsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add += int64(targ.Plt) } return case 256 + ld.R_X86_64_GOTPCREL, 256 + ld.R_X86_64_GOTPCRELX, 256 + ld.R_X86_64_REX_GOTPCRELX: if targ.Type != obj.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 = obj.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 = obj.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 == obj.SDYNIMPORT { ld.Diag("unexpected R_X86_64_64 relocation for dynamic symbol %s", targ.Name) } r.Type = obj.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 = obj.R_ADDR if targ.Type == obj.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 == obj.SDYNIMPORT { addpltsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) r.Type = obj.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 = obj.R_PCREL if targ.Type == obj.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: if targ.Type != obj.SDYNIMPORT { // have symbol // turn MOVQ of GOT entry into LEAQ of symbol itself if r.Off < 2 || s.P[r.Off-2] != 0x8b { ld.Diag("unexpected GOT_LOAD reloc for non-dynamic symbol %s", targ.Name) return } s.P[r.Off-2] = 0x8d r.Type = obj.R_PCREL return } fallthrough // fall through case 512 + ld.MACHO_X86_64_RELOC_GOT*2 + 1: if targ.Type != obj.SDYNIMPORT { ld.Diag("unexpected GOT reloc for non-dynamic symbol %s", targ.Name) } addgotsym(targ) r.Type = obj.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) return } // Handle references to ELF symbols from our own object files. if targ.Type != obj.SDYNIMPORT { return } switch r.Type { case obj.R_CALL, obj.R_PCREL: if ld.HEADTYPE == obj.Hwindows { // nothing to do, the relocation will be laid out in pereloc1 return } else { // for both ELF and Mach-O addpltsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) return } case obj.R_ADDR: if s.Type == obj.STEXT && ld.Iself { if ld.HEADTYPE == obj.Hsolaris { addpltsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add += int64(targ.Plt) return } // The code is asking for the address of an external // function. We provide it with the address of the // correspondent GOT symbol. addgotsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) return } if s.Type != obj.SDATA { break } if ld.Iself { ld.Adddynsym(ld.Ctxt, targ) rela := ld.Linklookup(ld.Ctxt, ".rela", 0) ld.Addaddrplus(ld.Ctxt, rela, s, int64(r.Off)) if r.Siz == 8 { ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(targ.Dynid), ld.R_X86_64_64)) } else { ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(targ.Dynid), ld.R_X86_64_32)) } ld.Adduint64(ld.Ctxt, rela, uint64(r.Add)) r.Type = 256 // ignore during relocsym return } if ld.HEADTYPE == obj.Hdarwin && s.Size == int64(ld.Thearch.Ptrsize) && r.Off == 0 { // Mach-O relocations are a royal pain to lay out. // They use a compact stateful bytecode representation // that is too much bother to deal with. // Instead, interpret the C declaration // void *_Cvar_stderr = &stderr; // as making _Cvar_stderr the name of a GOT entry // for stderr. This is separate from the usual GOT entry, // just in case the C code assigns to the variable, // and of course it only works for single pointers, // but we only need to support cgo and that's all it needs. ld.Adddynsym(ld.Ctxt, targ) got := ld.Linklookup(ld.Ctxt, ".got", 0) s.Type = got.Type | obj.SSUB s.Outer = got s.Sub = got.Sub got.Sub = s s.Value = got.Size ld.Adduint64(ld.Ctxt, got, 0) ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.got", 0), uint32(targ.Dynid)) r.Type = 256 // ignore during relocsym return } if ld.HEADTYPE == obj.Hwindows { // nothing to do, the relocation will be laid out in pereloc1 return } } ld.Ctxt.Cursym = s ld.Diag("unsupported relocation for dynamic symbol %s (type=%d stype=%d)", targ.Name, r.Type, targ.Type) }
func asmb() { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f asmb\n", obj.Cputime()) } ld.Bso.Flush() 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.Bso.Flush() 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.Bso.Flush() ld.Cseek(int64(ld.Segdata.Fileoff)) ld.Datblk(int64(ld.Segdata.Vaddr), int64(ld.Segdata.Filelen)) machlink := uint32(0) if ld.HEADTYPE == obj.Hdarwin { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } dwarfoff := uint32(ld.Rnd(int64(uint64(ld.HEADR)+ld.Segtext.Length), int64(ld.INITRND)) + ld.Rnd(int64(ld.Segdata.Filelen), int64(ld.INITRND))) ld.Cseek(int64(dwarfoff)) ld.Segdwarf.Fileoff = uint64(ld.Cpos()) ld.Dwarfemitdebugsections() ld.Segdwarf.Filelen = uint64(ld.Cpos()) - ld.Segdwarf.Fileoff machlink = uint32(ld.Domacholink()) } ld.Symsize = 0 ld.Spsize = 0 ld.Lcsize = 0 symo := uint32(0) if ld.Debug['s'] == 0 { // TODO: rationalize if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f sym\n", obj.Cputime()) } ld.Bso.Flush() switch ld.HEADTYPE { default: if ld.Iself { symo = uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen) symo = uint32(ld.Rnd(int64(symo), int64(ld.INITRND))) } case obj.Hplan9: symo = uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen) case obj.Hdarwin: symo = uint32(ld.Segdwarf.Fileoff + uint64(ld.Rnd(int64(ld.Segdwarf.Filelen), int64(ld.INITRND))) + uint64(machlink)) case obj.Hwindows: symo = uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen) symo = uint32(ld.Rnd(int64(symo), ld.PEFILEALIGN)) } ld.Cseek(int64(symo)) switch ld.HEADTYPE { default: if ld.Iself { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f elfsym\n", obj.Cputime()) } ld.Asmelfsym() ld.Cflush() ld.Cwrite(ld.Elfstrdat) if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } ld.Dwarfemitdebugsections() if ld.Linkmode == ld.LinkExternal { ld.Elfemitreloc() } } case obj.Hplan9: ld.Asmplan9sym() ld.Cflush() sym := ld.Linklookup(ld.Ctxt, "pclntab", 0) if sym != nil { ld.Lcsize = int32(len(sym.P)) for i := 0; int32(i) < ld.Lcsize; i++ { ld.Cput(uint8(sym.P[i])) } ld.Cflush() } case obj.Hwindows: if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } ld.Dwarfemitdebugsections() case obj.Hdarwin: if ld.Linkmode == ld.LinkExternal { ld.Machoemitreloc() } } } if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f headr\n", obj.Cputime()) } ld.Bso.Flush() ld.Cseek(0) switch ld.HEADTYPE { default: case obj.Hplan9: /* plan9 */ magic := int32(4*11*11 + 7) ld.Lputb(uint32(magic)) /* magic */ ld.Lputb(uint32(ld.Segtext.Filelen)) /* sizes */ ld.Lputb(uint32(ld.Segdata.Filelen)) ld.Lputb(uint32(ld.Segdata.Length - ld.Segdata.Filelen)) ld.Lputb(uint32(ld.Symsize)) /* nsyms */ ld.Lputb(uint32(ld.Entryvalue())) /* va of entry */ ld.Lputb(uint32(ld.Spsize)) /* sp offsets */ ld.Lputb(uint32(ld.Lcsize)) /* line offsets */ case obj.Hdarwin: ld.Asmbmacho() case obj.Hlinux, obj.Hfreebsd, obj.Hnetbsd, obj.Hopenbsd, obj.Hnacl: ld.Asmbelf(int64(symo)) case obj.Hwindows: ld.Asmbpe() } ld.Cflush() }
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 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.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 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_ARM_PLT32: r.Type = obj.R_CALLARM if targ.Type == obj.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(braddoff(int32(r.Add), targ.Plt/4)) } return case 256 + ld.R_ARM_THM_PC22: // R_ARM_THM_CALL ld.Exitf("R_ARM_THM_CALL, are you using -marm?") return case 256 + ld.R_ARM_GOT32: // R_ARM_GOT_BREL if targ.Type != obj.SDYNIMPORT { addgotsyminternal(ld.Ctxt, targ) } else { addgotsym(ld.Ctxt, targ) } r.Type = obj.R_CONST // write r->add during relocsym r.Sym = nil r.Add += int64(targ.Got) return case 256 + ld.R_ARM_GOT_PREL: // GOT(nil) + A - nil if targ.Type != obj.SDYNIMPORT { addgotsyminternal(ld.Ctxt, targ) } else { addgotsym(ld.Ctxt, targ) } r.Type = obj.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) + 4 return case 256 + ld.R_ARM_GOTOFF: // R_ARM_GOTOFF32 r.Type = obj.R_GOTOFF return case 256 + ld.R_ARM_GOTPC: // R_ARM_BASE_PREL r.Type = obj.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += 4 return case 256 + ld.R_ARM_CALL: r.Type = obj.R_CALLARM if targ.Type == obj.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(braddoff(int32(r.Add), targ.Plt/4)) } return case 256 + ld.R_ARM_REL32: // R_ARM_REL32 r.Type = obj.R_PCREL r.Add += 4 return case 256 + ld.R_ARM_ABS32: if targ.Type == obj.SDYNIMPORT { ld.Diag("unexpected R_ARM_ABS32 relocation for dynamic symbol %s", targ.Name) } r.Type = obj.R_ADDR return // we can just ignore this, because we are targeting ARM V5+ anyway case 256 + ld.R_ARM_V4BX: if r.Sym != nil { // R_ARM_V4BX is ABS relocation, so this symbol is a dummy symbol, ignore it r.Sym.Type = 0 } r.Sym = nil return case 256 + ld.R_ARM_PC24, 256 + ld.R_ARM_JUMP24: r.Type = obj.R_CALLARM if targ.Type == obj.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(braddoff(int32(r.Add), targ.Plt/4)) } return } // Handle references to ELF symbols from our own object files. if targ.Type != obj.SDYNIMPORT { return } switch r.Type { case obj.R_CALLARM: addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) return case obj.R_ADDR: if s.Type != obj.SDATA { break } if ld.Iself { ld.Adddynsym(ld.Ctxt, targ) rel := ld.Linklookup(ld.Ctxt, ".rel", 0) ld.Addaddrplus(ld.Ctxt, rel, s, int64(r.Off)) ld.Adduint32(ld.Ctxt, rel, ld.ELF32_R_INFO(uint32(targ.Dynid), ld.R_ARM_GLOB_DAT)) // we need a nil + A dynamic reloc r.Type = obj.R_CONST // write r->add during relocsym r.Sym = nil return } } ld.Ctxt.Cursym = s ld.Diag("unsupported relocation for dynamic symbol %s (type=%d stype=%d)", targ.Name, r.Type, targ.Type) }
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.BuildmodeCShared || ld.Buildmode == ld.BuildmodePIE || ld.DynlinkingGo() { ld.Linkmode = ld.LinkExternal got := ld.Linklookup(ld.Ctxt, "_GLOBAL_OFFSET_TABLE_", 0) got.Type = obj.SDYNIMPORT got.Reachable = true } 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.INITTEXT == -1 { ld.INITTEXT = 4096 + 32 } 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.INITTEXT == -1 { ld.INITTEXT = 4096 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case obj.Hlinux, /* elf32 executable */ obj.Hfreebsd, obj.Hnetbsd, obj.Hopenbsd: ld.Elfinit() ld.HEADR = ld.ELFRESERVE if ld.INITTEXT == -1 { ld.INITTEXT = 0x08048000 + 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 = 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 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_386_PC32: if targ.Type == obj.SDYNIMPORT { ld.Diag("unexpected R_386_PC32 relocation for dynamic symbol %s", targ.Name) } if targ.Type == 0 || targ.Type == obj.SXREF { ld.Diag("unknown symbol %s in pcrel", targ.Name) } r.Type = obj.R_PCREL r.Add += 4 return case 256 + ld.R_386_PLT32: r.Type = obj.R_PCREL r.Add += 4 if targ.Type == obj.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add += int64(targ.Plt) } return case 256 + ld.R_386_GOT32, 256 + ld.R_386_GOT32X: if targ.Type != obj.SDYNIMPORT { // have symbol if r.Off >= 2 && s.P[r.Off-2] == 0x8b { // turn MOVL of GOT entry into LEAL of symbol address, relative to GOT. s.P[r.Off-2] = 0x8d r.Type = obj.R_GOTOFF return } if r.Off >= 2 && s.P[r.Off-2] == 0xff && s.P[r.Off-1] == 0xb3 { // turn PUSHL of GOT entry into PUSHL of symbol itself. // use unnecessary SS prefix to keep instruction same length. s.P[r.Off-2] = 0x36 s.P[r.Off-1] = 0x68 r.Type = obj.R_ADDR return } ld.Diag("unexpected GOT reloc for non-dynamic symbol %s", targ.Name) return } addgotsym(ld.Ctxt, targ) r.Type = obj.R_CONST // write r->add during relocsym r.Sym = nil r.Add += int64(targ.Got) return case 256 + ld.R_386_GOTOFF: r.Type = obj.R_GOTOFF return case 256 + ld.R_386_GOTPC: r.Type = obj.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += 4 return case 256 + ld.R_386_32: if targ.Type == obj.SDYNIMPORT { ld.Diag("unexpected R_386_32 relocation for dynamic symbol %s", targ.Name) } r.Type = obj.R_ADDR return case 512 + ld.MACHO_GENERIC_RELOC_VANILLA*2 + 0: r.Type = obj.R_ADDR if targ.Type == obj.SDYNIMPORT { ld.Diag("unexpected reloc for dynamic symbol %s", targ.Name) } return case 512 + ld.MACHO_GENERIC_RELOC_VANILLA*2 + 1: if targ.Type == obj.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) r.Type = obj.R_PCREL return } r.Type = obj.R_PCREL return case 512 + ld.MACHO_FAKE_GOTPCREL: if targ.Type != obj.SDYNIMPORT { // have symbol // turn MOVL of GOT entry into LEAL of symbol itself if r.Off < 2 || s.P[r.Off-2] != 0x8b { ld.Diag("unexpected GOT reloc for non-dynamic symbol %s", targ.Name) return } s.P[r.Off-2] = 0x8d r.Type = obj.R_PCREL return } addgotsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) r.Type = obj.R_PCREL return } // Handle references to ELF symbols from our own object files. if targ.Type != obj.SDYNIMPORT { return } switch r.Type { case obj.R_CALL, obj.R_PCREL: addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) return case obj.R_ADDR: if s.Type != obj.SDATA { break } if ld.Iself { ld.Adddynsym(ld.Ctxt, targ) rel := ld.Linklookup(ld.Ctxt, ".rel", 0) ld.Addaddrplus(ld.Ctxt, rel, s, int64(r.Off)) ld.Adduint32(ld.Ctxt, rel, ld.ELF32_R_INFO(uint32(targ.Dynid), ld.R_386_32)) r.Type = obj.R_CONST // write r->add during relocsym r.Sym = nil return } if ld.HEADTYPE == obj.Hdarwin && s.Size == PtrSize && r.Off == 0 { // Mach-O relocations are a royal pain to lay out. // They use a compact stateful bytecode representation // that is too much bother to deal with. // Instead, interpret the C declaration // void *_Cvar_stderr = &stderr; // as making _Cvar_stderr the name of a GOT entry // for stderr. This is separate from the usual GOT entry, // just in case the C code assigns to the variable, // and of course it only works for single pointers, // but we only need to support cgo and that's all it needs. ld.Adddynsym(ld.Ctxt, targ) got := ld.Linklookup(ld.Ctxt, ".got", 0) s.Type = got.Type | obj.SSUB s.Outer = got s.Sub = got.Sub got.Sub = s s.Value = got.Size ld.Adduint32(ld.Ctxt, got, 0) ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.got", 0), uint32(targ.Dynid)) r.Type = 256 // ignore during relocsym return } if ld.HEADTYPE == obj.Hwindows && s.Size == PtrSize { // nothing to do, the relocation will be laid out in pereloc1 return } } ld.Ctxt.Cursym = s ld.Diag("unsupported relocation for dynamic symbol %s (type=%d stype=%d)", targ.Name, r.Type, targ.Type) }
func asmb() { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f asmb\n", obj.Cputime()) } ld.Bso.Flush() 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.Bso.Flush() 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.Bso.Flush() ld.Cseek(int64(ld.Segdata.Fileoff)) ld.Datblk(int64(ld.Segdata.Vaddr), int64(ld.Segdata.Filelen)) /* output symbol table */ ld.Symsize = 0 ld.Lcsize = 0 symo := uint32(0) if ld.Debug['s'] == 0 { // TODO: rationalize if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f sym\n", obj.Cputime()) } ld.Bso.Flush() switch ld.HEADTYPE { default: if ld.Iself { symo = uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen) symo = uint32(ld.Rnd(int64(symo), int64(ld.INITRND))) } case obj.Hplan9: symo = uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen) } ld.Cseek(int64(symo)) switch ld.HEADTYPE { default: if ld.Iself { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f elfsym\n", obj.Cputime()) } ld.Asmelfsym() ld.Cflush() ld.Cwrite(ld.Elfstrdat) if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } ld.Dwarfemitdebugsections() if ld.Linkmode == ld.LinkExternal { ld.Elfemitreloc() } } case obj.Hplan9: ld.Asmplan9sym() ld.Cflush() sym := ld.Linklookup(ld.Ctxt, "pclntab", 0) if sym != nil { ld.Lcsize = int32(len(sym.P)) for i := 0; int32(i) < ld.Lcsize; i++ { ld.Cput(uint8(sym.P[i])) } ld.Cflush() } } } ld.Ctxt.Cursym = nil if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f header\n", obj.Cputime()) } ld.Bso.Flush() ld.Cseek(0) switch ld.HEADTYPE { default: case obj.Hplan9: /* plan 9 */ magic := uint32(4*18*18 + 7) if ld.Thestring == "mips64le" { magic = uint32(4*26*26 + 7) } ld.Thearch.Lput(uint32(magic)) /* magic */ ld.Thearch.Lput(uint32(ld.Segtext.Filelen)) /* sizes */ ld.Thearch.Lput(uint32(ld.Segdata.Filelen)) ld.Thearch.Lput(uint32(ld.Segdata.Length - ld.Segdata.Filelen)) ld.Thearch.Lput(uint32(ld.Symsize)) /* nsyms */ ld.Thearch.Lput(uint32(ld.Entryvalue())) /* va of entry */ ld.Thearch.Lput(0) ld.Thearch.Lput(uint32(ld.Lcsize)) case obj.Hlinux, obj.Hfreebsd, obj.Hnetbsd, obj.Hopenbsd, obj.Hnacl: ld.Asmbelf(int64(symo)) } ld.Cflush() if ld.Debug['c'] != 0 { fmt.Printf("textsize=%d\n", ld.Segtext.Filelen) fmt.Printf("datsize=%d\n", ld.Segdata.Filelen) fmt.Printf("bsssize=%d\n", ld.Segdata.Length-ld.Segdata.Filelen) fmt.Printf("symsize=%d\n", ld.Symsize) fmt.Printf("lcsize=%d\n", ld.Lcsize) fmt.Printf("total=%d\n", ld.Segtext.Filelen+ld.Segdata.Length+uint64(ld.Symsize)+uint64(ld.Lcsize)) } }
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int { if ld.Linkmode == ld.LinkExternal { switch r.Type { case obj.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 != obj.SHOSTOBJ && rs.Type != obj.SDYNIMPORT && 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 == obj.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 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 // The following three arch specific relocations are only for generation of // Linux/ARM ELF's PLT entry (3 assembler instruction) case obj.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 obj.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 obj.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 obj.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 }
func asmb() { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f asmb\n", obj.Cputime()) } ld.Bso.Flush() if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f codeblk\n", obj.Cputime()) } ld.Bso.Flush() 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.Bso.Flush() 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.Bso.Flush() ld.Cseek(int64(ld.Segdata.Fileoff)) ld.Datblk(int64(ld.Segdata.Vaddr), int64(ld.Segdata.Filelen)) machlink := int64(0) if ld.HEADTYPE == obj.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 obj.Hplan9, obj.Helf: break case obj.Hdarwin: ld.Debug['8'] = 1 /* 64-bit addresses */ case obj.Hlinux, obj.Hfreebsd, obj.Hnetbsd, obj.Hopenbsd, obj.Hdragonfly, obj.Hsolaris: ld.Debug['8'] = 1 /* 64-bit addresses */ case obj.Hnacl, obj.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.Bso.Flush() switch ld.HEADTYPE { default: case obj.Hplan9, obj.Helf: ld.Debug['s'] = 1 symo = int64(ld.Segdata.Fileoff + ld.Segdata.Filelen) case obj.Hdarwin: symo = int64(ld.Segdwarf.Fileoff + uint64(ld.Rnd(int64(ld.Segdwarf.Filelen), int64(ld.INITRND))) + uint64(machlink)) case obj.Hlinux, obj.Hfreebsd, obj.Hnetbsd, obj.Hopenbsd, obj.Hdragonfly, obj.Hsolaris, obj.Hnacl: symo = int64(ld.Segdata.Fileoff + ld.Segdata.Filelen) symo = ld.Rnd(symo, int64(ld.INITRND)) case obj.Hwindows: symo = int64(ld.Segdata.Fileoff + ld.Segdata.Filelen) symo = ld.Rnd(symo, ld.PEFILEALIGN) } ld.Cseek(symo) switch ld.HEADTYPE { default: if ld.Iself { ld.Cseek(symo) ld.Asmelfsym() ld.Cflush() ld.Cwrite(ld.Elfstrdat) if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } ld.Dwarfemitdebugsections() if ld.Linkmode == ld.LinkExternal { ld.Elfemitreloc() } } case obj.Hplan9: ld.Asmplan9sym() ld.Cflush() sym := ld.Linklookup(ld.Ctxt, "pclntab", 0) if sym != nil { ld.Lcsize = int32(len(sym.P)) for i := 0; int32(i) < ld.Lcsize; i++ { ld.Cput(uint8(sym.P[i])) } ld.Cflush() } case obj.Hwindows: if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } ld.Dwarfemitdebugsections() case obj.Hdarwin: if ld.Linkmode == ld.LinkExternal { ld.Machoemitreloc() } } } if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f headr\n", obj.Cputime()) } ld.Bso.Flush() ld.Cseek(0) switch ld.HEADTYPE { default: case obj.Hplan9: /* plan9 */ magic := int32(4*26*26 + 7) magic |= 0x00008000 /* fat header */ ld.Lputb(uint32(magic)) /* magic */ ld.Lputb(uint32(ld.Segtext.Filelen)) /* sizes */ ld.Lputb(uint32(ld.Segdata.Filelen)) ld.Lputb(uint32(ld.Segdata.Length - ld.Segdata.Filelen)) ld.Lputb(uint32(ld.Symsize)) /* nsyms */ vl := ld.Entryvalue() ld.Lputb(PADDR(uint32(vl))) /* va of entry */ ld.Lputb(uint32(ld.Spsize)) /* sp offsets */ ld.Lputb(uint32(ld.Lcsize)) /* line offsets */ ld.Vputb(uint64(vl)) /* va of entry */ case obj.Hdarwin: ld.Asmbmacho() case obj.Hlinux, obj.Hfreebsd, obj.Hnetbsd, obj.Hopenbsd, obj.Hdragonfly, obj.Hsolaris, obj.Hnacl: ld.Asmbelf(symo) case obj.Hwindows: ld.Asmbpe() } ld.Cflush() }
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 } switch ld.Buildmode { case ld.BuildmodePIE, ld.BuildmodeShared: ld.Linkmode = ld.LinkExternal } if ld.Linkshared { ld.Linkmode = ld.LinkExternal } if ld.Linkmode == ld.LinkExternal { toc := ld.Linklookup(ld.Ctxt, ".TOC.", 0) toc.Type = obj.SDYNIMPORT } 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: 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: /* ppc64 elf */ if ld.Thestring == "ppc64" { ld.Debug['d'] = 1 // TODO(austin): ELF ABI v1 not supported yet } 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 = 0x10000 } 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 } } 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)) } }