diff options
Diffstat (limited to 'lld/ELF/Target.cpp')
| -rw-r--r-- | lld/ELF/Target.cpp | 107 |
1 files changed, 79 insertions, 28 deletions
diff --git a/lld/ELF/Target.cpp b/lld/ELF/Target.cpp index 78e5df6561b..bad344b0bc3 100644 --- a/lld/ELF/Target.cpp +++ b/lld/ELF/Target.cpp @@ -46,13 +46,15 @@ namespace { class X86TargetInfo final : public TargetInfo { public: X86TargetInfo(); + void writeGotPltHeaderEntries(uint8_t *Buf) const override; unsigned getDynReloc(unsigned Type) const override; bool isTlsDynReloc(unsigned Type) const override; void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override; void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr) const override; - void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const override; + void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const override; bool relocNeedsCopy(uint32_t Type, const SymbolBody &S) const override; bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override; bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override; @@ -69,8 +71,9 @@ public: void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override; void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr) const override; - void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const override; + void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const override; bool relocNeedsCopy(uint32_t Type, const SymbolBody &S) const override; bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override; bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override; @@ -96,8 +99,9 @@ public: void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override; void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr) const override; - void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const override; + void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const override; bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override; bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override; void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type, uint64_t P, @@ -113,8 +117,9 @@ public: void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override; void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr) const override; - void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const override; + void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const override; bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override; bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override; void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type, uint64_t P, @@ -129,8 +134,9 @@ public: void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override; void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr) const override; - void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const override; + void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const override; bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override; bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override; void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type, uint64_t P, @@ -195,6 +201,18 @@ X86TargetInfo::X86TargetInfo() { GotReloc = R_386_GLOB_DAT; GotRefReloc = R_386_GOT32; PltReloc = R_386_JUMP_SLOT; + LazyRelocations = true; + PltEntrySize = 16; + PltZeroEntrySize = 16; +} + +void X86TargetInfo::writeGotPltHeaderEntries(uint8_t *Buf) const { + write32le(Buf, Out<ELF32LE>::Dynamic->getVA()); +} + +void X86TargetInfo::writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const { + // Skip 6 bytes of "pushl (GOT+4)" + write32le(Buf, Plt + 6); } unsigned X86TargetInfo::getDynReloc(unsigned Type) const { @@ -211,17 +229,44 @@ bool X86TargetInfo::isTlsDynReloc(unsigned Type) const { return false; } -void X86TargetInfo::writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const {} void X86TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr) const {} + uint64_t PltEntryAddr) const { + // Executable files and shared object files have + // separate procedure linkage tables. + if (Config->Shared) { + const uint8_t V[] = { + 0xff, 0xb3, 0x04, 0x00, 0x00, 0x00, // pushl 4(%ebx + 0xff, 0xa3, 0x08, 0x00, 0x00, 0x00, // jmp *8(%ebx) + 0x90, 0x90, 0x90, 0x90 // nop;nop;nop;nop + }; + memcpy(Buf, V, sizeof(V)); + return; + } -void X86TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const { - // jmpl *val; nop; nop - const uint8_t Inst[] = {0xff, 0x25, 0, 0, 0, 0, 0x90, 0x90}; + const uint8_t PltData[] = { + 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, // pushl (GOT+4) + 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp *(GOT+8) + 0x90, 0x90, 0x90, 0x90 // nop;nop;nop;nop + }; + memcpy(Buf, PltData, sizeof(PltData)); + write32le(Buf + 2, GotEntryAddr + 4); // GOT+4 + write32le(Buf + 8, GotEntryAddr + 8); // GOT+8 +} + +void X86TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr, + uint64_t GotEntryAddr, uint64_t PltEntryAddr, + int32_t Index, unsigned RelOff) const { + const uint8_t Inst[] = { + 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, // jmp *foo_in_GOT|*foo@GOT(%ebx) + 0x68, 0x00, 0x00, 0x00, 0x00, // pushl $reloc_offset + 0xe9, 0x00, 0x00, 0x00, 0x00 // jmp .PLT0@PC + }; memcpy(Buf, Inst, sizeof(Inst)); - assert(isUInt<32>(GotEntryAddr)); - write32le(Buf + 2, GotEntryAddr); + // jmp *foo@GOT(%ebx) or jmp *foo_in_GOT + Buf[1] = Config->Shared ? 0xa3 : 0x25; + write32le(Buf + 2, Config->Shared ? (GotEntryAddr - GotAddr) : GotEntryAddr); + write32le(Buf + 7, RelOff); + write32le(Buf + 12, -Index * PltEntrySize - PltZeroEntrySize - 16); } bool X86TargetInfo::relocNeedsCopy(uint32_t Type, const SymbolBody &S) const { @@ -303,9 +348,10 @@ void X86_64TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, write32le(Buf + 8, GotEntryAddr - PltEntryAddr + 4); // GOT+16 } -void X86_64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, - int32_t Index) const { +void X86_64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr, + uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const { const uint8_t Inst[] = { 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmpq *got(%rip) 0x68, 0x00, 0x00, 0x00, 0x00, // pushq <relocation index> @@ -604,8 +650,10 @@ uint64_t getPPC64TocBase() { void PPC64TargetInfo::writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const {} void PPC64TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr) const {} -void PPC64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const { +void PPC64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr, + uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const { uint64_t Off = GotEntryAddr - getPPC64TocBase(); // FIXME: What we should do, in theory, is get the offset of the function @@ -816,9 +864,10 @@ void AArch64TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, GotEntryAddr + 16); } -void AArch64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, - int32_t Index) const { +void AArch64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr, + uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const { const uint8_t Inst[] = { 0x10, 0x00, 0x00, 0x90, // adrp x16, Page(&(.plt.got[n])) 0x11, 0x02, 0x40, 0xf9, // ldr x17, [x16, Offset(&(.plt.got[n]))] @@ -977,8 +1026,10 @@ template <class ELFT> void MipsTargetInfo<ELFT>::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr, uint64_t PltEntryAddr) const {} template <class ELFT> -void MipsTargetInfo<ELFT>::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index) const {} +void MipsTargetInfo<ELFT>::writePltEntry(uint8_t *Buf, uint64_t GotAddr, + uint64_t GotEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const {} template <class ELFT> bool MipsTargetInfo<ELFT>::relocNeedsGot(uint32_t Type, |
