Index: lld/ELF/CMakeLists.txt =================================================================== --- lld/ELF/CMakeLists.txt +++ lld/ELF/CMakeLists.txt @@ -7,6 +7,14 @@ endif() add_lld_library(lldELF + arch/AArch64.cpp + arch/AMDGPU.cpp + arch/ARM.cpp + arch/Mips.cpp + arch/PPC.cpp + arch/PPC64.cpp + arch/X86.cpp + arch/X86_64.cpp Driver.cpp DriverUtils.cpp EhFrame.cpp Index: lld/ELF/Target.h =================================================================== --- lld/ELF/Target.h +++ lld/ELF/Target.h @@ -10,6 +10,7 @@ #ifndef LLD_ELF_TARGET_H #define LLD_ELF_TARGET_H +#include "Error.h" #include "InputSection.h" #include "llvm/ADT/StringRef.h" #include "llvm/Object/ELF.h" @@ -17,6 +18,8 @@ #include namespace lld { +std::string toString(uint32_t RelType); + namespace elf { class InputFile; class SymbolBody; @@ -102,14 +105,52 @@ virtual void relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const; }; +TargetInfo *createAArch64TargetInfo(); +TargetInfo *createAMDGPUTargetInfo(); +TargetInfo *createARMTargetInfo(); +TargetInfo *createPPC64TargetInfo(); +TargetInfo *createPPCTargetInfo(); +TargetInfo *createX32TargetInfo(); +TargetInfo *createX86TargetInfo(); +TargetInfo *createX86_64TargetInfo(); +template TargetInfo *createMipsTargetInfo(); + +std::string getErrorLocation(const uint8_t *Loc); + uint64_t getPPC64TocBase(); uint64_t getAArch64Page(uint64_t Expr); extern TargetInfo *Target; TargetInfo *createTarget(); + +template +static void checkInt(uint8_t *Loc, int64_t V, uint32_t Type) { + if (!llvm::isInt(V)) + error(getErrorLocation(Loc) + "relocation " + lld::toString(Type) + + " out of range"); } -std::string toString(uint32_t RelType); +template +static void checkUInt(uint8_t *Loc, uint64_t V, uint32_t Type) { + if (!llvm::isUInt(V)) + error(getErrorLocation(Loc) + "relocation " + lld::toString(Type) + + " out of range"); +} + +template +static void checkIntUInt(uint8_t *Loc, uint64_t V, uint32_t Type) { + if (!llvm::isInt(V) && !llvm::isUInt(V)) + error(getErrorLocation(Loc) + "relocation " + lld::toString(Type) + + " out of range"); +} + +template +static void checkAlignment(uint8_t *Loc, uint64_t V, uint32_t Type) { + if ((V & (N - 1)) != 0) + error(getErrorLocation(Loc) + "improper alignment for relocation " + + lld::toString(Type)); +} +} // namespace elf } #endif Index: lld/ELF/Target.cpp =================================================================== --- lld/ELF/Target.cpp +++ lld/ELF/Target.cpp @@ -27,22 +27,18 @@ #include "Target.h" #include "Error.h" #include "InputFiles.h" -#include "Memory.h" #include "OutputSections.h" #include "SymbolTable.h" #include "Symbols.h" -#include "SyntheticSections.h" -#include "Thunks.h" -#include "Writer.h" -#include "llvm/ADT/ArrayRef.h" -#include "llvm/BinaryFormat/ELF.h" #include "llvm/Object/ELF.h" -#include "llvm/Support/Endian.h" using namespace llvm; using namespace llvm::object; -using namespace llvm::support::endian; using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +TargetInfo *elf::Target; std::string lld::toString(uint32_t Type) { StringRef S = getELFRelocationTypeName(elf::Config->EMachine, Type); @@ -51,13 +47,41 @@ return S; } -namespace lld { -namespace elf { - -TargetInfo *Target; - -static void or32le(uint8_t *P, int32_t V) { write32le(P, read32le(P) | V); } -static void or32be(uint8_t *P, int32_t V) { write32be(P, read32be(P) | V); } +TargetInfo *elf::createTarget() { + switch (Config->EMachine) { + case EM_386: + case EM_IAMCU: + return createX86TargetInfo(); + case EM_AARCH64: + return createAArch64TargetInfo(); + case EM_AMDGPU: + return createAMDGPUTargetInfo(); + case EM_ARM: + return createARMTargetInfo(); + case EM_MIPS: + switch (Config->EKind) { + case ELF32LEKind: + return createMipsTargetInfo(); + case ELF32BEKind: + return createMipsTargetInfo(); + case ELF64LEKind: + return createMipsTargetInfo(); + case ELF64BEKind: + return createMipsTargetInfo(); + default: + fatal("unsupported MIPS target"); + } + case EM_PPC: + return createPPCTargetInfo(); + case EM_PPC64: + return createPPC64TargetInfo(); + case EM_X86_64: + if (Config->EKind == ELF32LEKind) + return createX32TargetInfo(); + return createX86_64TargetInfo(); + } + fatal("unknown target machine"); +} template static std::string getErrorLoc(const uint8_t *Loc) { for (InputSectionBase *D : InputSections) { @@ -72,7 +96,7 @@ return ""; } -static std::string getErrorLocation(const uint8_t *Loc) { +std::string elf::getErrorLocation(const uint8_t *Loc) { switch (Config->EKind) { case ELF32LEKind: return getErrorLoc(Loc); @@ -87,204 +111,6 @@ } } -template -static void checkInt(uint8_t *Loc, int64_t V, uint32_t Type) { - if (!isInt(V)) - error(getErrorLocation(Loc) + "relocation " + toString(Type) + - " out of range"); -} - -template -static void checkUInt(uint8_t *Loc, uint64_t V, uint32_t Type) { - if (!isUInt(V)) - error(getErrorLocation(Loc) + "relocation " + toString(Type) + - " out of range"); -} - -template -static void checkIntUInt(uint8_t *Loc, uint64_t V, uint32_t Type) { - if (!isInt(V) && !isUInt(V)) - error(getErrorLocation(Loc) + "relocation " + toString(Type) + - " out of range"); -} - -template -static void checkAlignment(uint8_t *Loc, uint64_t V, uint32_t Type) { - if ((V & (N - 1)) != 0) - error(getErrorLocation(Loc) + "improper alignment for relocation " + - toString(Type)); -} - -namespace { -class X86TargetInfo final : public TargetInfo { -public: - X86TargetInfo(); - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; - int64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const override; - void writeGotPltHeader(uint8_t *Buf) const override; - uint32_t getDynRel(uint32_t Type) const override; - void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; - void writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const override; - void writePltHeader(uint8_t *Buf) const override; - void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, - int32_t Index, unsigned RelOff) const override; - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - - RelExpr adjustRelaxExpr(uint32_t Type, const uint8_t *Data, - RelExpr Expr) const override; - void relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; -}; - -template class X86_64TargetInfo final : public TargetInfo { -public: - X86_64TargetInfo(); - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; - bool isPicRel(uint32_t Type) const override; - void writeGotPltHeader(uint8_t *Buf) const override; - void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; - void writePltHeader(uint8_t *Buf) const override; - void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, - int32_t Index, unsigned RelOff) const override; - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - - RelExpr adjustRelaxExpr(uint32_t Type, const uint8_t *Data, - RelExpr Expr) const override; - void relaxGot(uint8_t *Loc, uint64_t Val) const override; - void relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - -private: - void relaxGotNoPic(uint8_t *Loc, uint64_t Val, uint8_t Op, - uint8_t ModRm) const; -}; - -class PPCTargetInfo final : public TargetInfo { -public: - PPCTargetInfo(); - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; -}; - -class PPC64TargetInfo final : public TargetInfo { -public: - PPC64TargetInfo(); - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; - void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, - int32_t Index, unsigned RelOff) const override; - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; -}; - -class AArch64TargetInfo final : public TargetInfo { -public: - AArch64TargetInfo(); - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; - bool isPicRel(uint32_t Type) const override; - void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; - void writePltHeader(uint8_t *Buf) const override; - void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, - int32_t Index, unsigned RelOff) const override; - bool usesOnlyLowPageBits(uint32_t Type) const override; - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - RelExpr adjustRelaxExpr(uint32_t Type, const uint8_t *Data, - RelExpr Expr) const override; - void relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - void relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; -}; - -class AMDGPUTargetInfo final : public TargetInfo { -public: - AMDGPUTargetInfo(); - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; -}; - -class ARMTargetInfo final : public TargetInfo { -public: - ARMTargetInfo(); - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; - bool isPicRel(uint32_t Type) const override; - uint32_t getDynRel(uint32_t Type) const override; - int64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const override; - void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; - void writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const override; - void writePltHeader(uint8_t *Buf) const override; - void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, - int32_t Index, unsigned RelOff) const override; - void addPltSymbols(InputSectionBase *IS, uint64_t Off) const override; - void addPltHeaderSymbols(InputSectionBase *ISD) const override; - bool needsThunk(RelExpr Expr, uint32_t RelocType, const InputFile *File, - const SymbolBody &S) const override; - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; -}; - -template class MipsTargetInfo final : public TargetInfo { -public: - MipsTargetInfo(); - RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const override; - int64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const override; - bool isPicRel(uint32_t Type) const override; - uint32_t getDynRel(uint32_t Type) const override; - void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; - void writePltHeader(uint8_t *Buf) const override; - void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, - int32_t Index, unsigned RelOff) const override; - bool needsThunk(RelExpr Expr, uint32_t RelocType, const InputFile *File, - const SymbolBody &S) const override; - void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; - bool usesOnlyLowPageBits(uint32_t Type) const override; -}; -} // anonymous namespace - -TargetInfo *createTarget() { - switch (Config->EMachine) { - case EM_386: - case EM_IAMCU: - return make(); - case EM_AARCH64: - return make(); - case EM_AMDGPU: - return make(); - case EM_ARM: - return make(); - case EM_MIPS: - switch (Config->EKind) { - case ELF32LEKind: - return make>(); - case ELF32BEKind: - return make>(); - case ELF64LEKind: - return make>(); - case ELF64BEKind: - return make>(); - default: - fatal("unsupported MIPS target"); - } - case EM_PPC: - return make(); - case EM_PPC64: - return make(); - case EM_X86_64: - if (Config->EKind == ELF32LEKind) - return make>(); - return make>(); - } - fatal("unknown target machine"); -} - TargetInfo::~TargetInfo() {} int64_t TargetInfo::getImplicitAddend(const uint8_t *Buf, uint32_t Type) const { @@ -330,2091 +156,3 @@ uint64_t Val) const { llvm_unreachable("Should not have claimed to be relaxable"); } - -X86TargetInfo::X86TargetInfo() { - CopyRel = R_386_COPY; - GotRel = R_386_GLOB_DAT; - PltRel = R_386_JUMP_SLOT; - IRelativeRel = R_386_IRELATIVE; - RelativeRel = R_386_RELATIVE; - TlsGotRel = R_386_TLS_TPOFF; - TlsModuleIndexRel = R_386_TLS_DTPMOD32; - TlsOffsetRel = R_386_TLS_DTPOFF32; - GotEntrySize = 4; - GotPltEntrySize = 4; - PltEntrySize = 16; - PltHeaderSize = 16; - TlsGdRelaxSkip = 2; - // 0xCC is the "int3" (call debug exception handler) instruction. - TrapInstr = 0xcccccccc; -} - -RelExpr X86TargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - switch (Type) { - case R_386_8: - case R_386_16: - case R_386_32: - case R_386_TLS_LDO_32: - return R_ABS; - case R_386_TLS_GD: - return R_TLSGD; - case R_386_TLS_LDM: - return R_TLSLD; - case R_386_PLT32: - return R_PLT_PC; - case R_386_PC8: - case R_386_PC16: - case R_386_PC32: - return R_PC; - case R_386_GOTPC: - return R_GOTONLY_PC_FROM_END; - case R_386_TLS_IE: - return R_GOT; - case R_386_GOT32: - case R_386_GOT32X: - // These relocations can be calculated in two different ways. - // Usual calculation is G + A - GOT what means an offset in GOT table - // (R_GOT_FROM_END). When instruction pointed by relocation has no base - // register, then relocations can be used when PIC code is disabled. In that - // case calculation is G + A, it resolves to an address of entry in GOT - // (R_GOT) and not an offset. - // - // To check that instruction has no base register we scan ModR/M byte. - // See "Table 2-2. 32-Bit Addressing Forms with the ModR/M Byte" - // (http://www.intel.com/content/dam/www/public/us/en/documents/manuals/ - // 64-ia-32-architectures-software-developer-instruction-set-reference-manual-325383.pdf) - if ((Loc[-1] & 0xc7) != 0x5) - return R_GOT_FROM_END; - if (Config->Pic) - error(toString(S.File) + ": relocation " + toString(Type) + " against '" + - S.getName() + - "' without base register can not be used when PIC enabled"); - return R_GOT; - case R_386_TLS_GOTIE: - return R_GOT_FROM_END; - case R_386_GOTOFF: - return R_GOTREL_FROM_END; - case R_386_TLS_LE: - return R_TLS; - case R_386_TLS_LE_32: - return R_NEG_TLS; - case R_386_NONE: - return R_NONE; - default: - error(toString(S.File) + ": unknown relocation type: " + toString(Type)); - return R_HINT; - } -} - -RelExpr X86TargetInfo::adjustRelaxExpr(uint32_t Type, const uint8_t *Data, - RelExpr Expr) const { - switch (Expr) { - default: - return Expr; - case R_RELAX_TLS_GD_TO_IE: - return R_RELAX_TLS_GD_TO_IE_END; - case R_RELAX_TLS_GD_TO_LE: - return R_RELAX_TLS_GD_TO_LE_NEG; - } -} - -void X86TargetInfo::writeGotPltHeader(uint8_t *Buf) const { - write32le(Buf, InX::Dynamic->getVA()); -} - -void X86TargetInfo::writeGotPlt(uint8_t *Buf, const SymbolBody &S) const { - // Entries in .got.plt initially points back to the corresponding - // PLT entries with a fixed offset to skip the first instruction. - write32le(Buf, S.getPltVA() + 6); -} - -void X86TargetInfo::writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const { - // An x86 entry is the address of the ifunc resolver function. - write32le(Buf, S.getVA()); -} - -uint32_t X86TargetInfo::getDynRel(uint32_t Type) const { - if (Type == R_386_TLS_LE) - return R_386_TLS_TPOFF; - if (Type == R_386_TLS_LE_32) - return R_386_TLS_TPOFF32; - return Type; -} - -void X86TargetInfo::writePltHeader(uint8_t *Buf) const { - if (Config->Pic) { - const uint8_t V[] = { - 0xff, 0xb3, 0x04, 0x00, 0x00, 0x00, // pushl GOTPLT+4(%ebx) - 0xff, 0xa3, 0x08, 0x00, 0x00, 0x00, // jmp *GOTPLT+8(%ebx) - 0x90, 0x90, 0x90, 0x90 // nop - }; - memcpy(Buf, V, sizeof(V)); - - uint32_t Ebx = InX::Got->getVA() + InX::Got->getSize(); - uint32_t GotPlt = InX::GotPlt->getVA() - Ebx; - write32le(Buf + 2, GotPlt + 4); - write32le(Buf + 8, GotPlt + 8); - return; - } - - const uint8_t PltData[] = { - 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, // pushl (GOTPLT+4) - 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp *(GOTPLT+8) - 0x90, 0x90, 0x90, 0x90 // nop - }; - memcpy(Buf, PltData, sizeof(PltData)); - uint32_t GotPlt = InX::GotPlt->getVA(); - write32le(Buf + 2, GotPlt + 4); - write32le(Buf + 8, GotPlt + 8); -} - -void X86TargetInfo::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, - 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)); - - if (Config->Pic) { - // jmp *foo@GOT(%ebx) - uint32_t Ebx = InX::Got->getVA() + InX::Got->getSize(); - Buf[1] = 0xa3; - write32le(Buf + 2, GotPltEntryAddr - Ebx); - } else { - // jmp *foo_in_GOT - Buf[1] = 0x25; - write32le(Buf + 2, GotPltEntryAddr); - } - - write32le(Buf + 7, RelOff); - write32le(Buf + 12, -Index * PltEntrySize - PltHeaderSize - 16); -} - -int64_t X86TargetInfo::getImplicitAddend(const uint8_t *Buf, - uint32_t Type) const { - switch (Type) { - default: - return 0; - case R_386_8: - case R_386_PC8: - return SignExtend64<8>(*Buf); - case R_386_16: - case R_386_PC16: - return SignExtend64<16>(read16le(Buf)); - case R_386_32: - case R_386_GOT32: - case R_386_GOT32X: - case R_386_GOTOFF: - case R_386_GOTPC: - case R_386_PC32: - case R_386_PLT32: - case R_386_TLS_LDO_32: - case R_386_TLS_LE: - return SignExtend64<32>(read32le(Buf)); - } -} - -void X86TargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // R_386_{PC,}{8,16} are not part of the i386 psABI, but they are - // being used for some 16-bit programs such as boot loaders, so - // we want to support them. - switch (Type) { - case R_386_8: - checkUInt<8>(Loc, Val, Type); - *Loc = Val; - break; - case R_386_PC8: - checkInt<8>(Loc, Val, Type); - *Loc = Val; - break; - case R_386_16: - checkUInt<16>(Loc, Val, Type); - write16le(Loc, Val); - break; - case R_386_PC16: - // R_386_PC16 is normally used with 16 bit code. In that situation - // the PC is 16 bits, just like the addend. This means that it can - // point from any 16 bit address to any other if the possibility - // of wrapping is included. - // The only restriction we have to check then is that the destination - // address fits in 16 bits. That is impossible to do here. The problem is - // that we are passed the final value, which already had the - // current location subtracted from it. - // We just check that Val fits in 17 bits. This misses some cases, but - // should have no false positives. - checkInt<17>(Loc, Val, Type); - write16le(Loc, Val); - break; - default: - checkInt<32>(Loc, Val, Type); - write32le(Loc, Val); - } -} - -void X86TargetInfo::relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // Convert - // leal x@tlsgd(, %ebx, 1), - // call __tls_get_addr@plt - // to - // movl %gs:0,%eax - // subl $x@ntpoff,%eax - const uint8_t Inst[] = { - 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, // movl %gs:0, %eax - 0x81, 0xe8, 0x00, 0x00, 0x00, 0x00 // subl 0(%ebx), %eax - }; - memcpy(Loc - 3, Inst, sizeof(Inst)); - write32le(Loc + 5, Val); -} - -void X86TargetInfo::relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // Convert - // leal x@tlsgd(, %ebx, 1), - // call __tls_get_addr@plt - // to - // movl %gs:0, %eax - // addl x@gotntpoff(%ebx), %eax - const uint8_t Inst[] = { - 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, // movl %gs:0, %eax - 0x03, 0x83, 0x00, 0x00, 0x00, 0x00 // addl 0(%ebx), %eax - }; - memcpy(Loc - 3, Inst, sizeof(Inst)); - write32le(Loc + 5, Val); -} - -// In some conditions, relocations can be optimized to avoid using GOT. -// This function does that for Initial Exec to Local Exec case. -void X86TargetInfo::relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // Ulrich's document section 6.2 says that @gotntpoff can - // be used with MOVL or ADDL instructions. - // @indntpoff is similar to @gotntpoff, but for use in - // position dependent code. - uint8_t Reg = (Loc[-1] >> 3) & 7; - - if (Type == R_386_TLS_IE) { - if (Loc[-1] == 0xa1) { - // "movl foo@indntpoff,%eax" -> "movl $foo,%eax" - // This case is different from the generic case below because - // this is a 5 byte instruction while below is 6 bytes. - Loc[-1] = 0xb8; - } else if (Loc[-2] == 0x8b) { - // "movl foo@indntpoff,%reg" -> "movl $foo,%reg" - Loc[-2] = 0xc7; - Loc[-1] = 0xc0 | Reg; - } else { - // "addl foo@indntpoff,%reg" -> "addl $foo,%reg" - Loc[-2] = 0x81; - Loc[-1] = 0xc0 | Reg; - } - } else { - assert(Type == R_386_TLS_GOTIE); - if (Loc[-2] == 0x8b) { - // "movl foo@gottpoff(%rip),%reg" -> "movl $foo,%reg" - Loc[-2] = 0xc7; - Loc[-1] = 0xc0 | Reg; - } else { - // "addl foo@gotntpoff(%rip),%reg" -> "leal foo(%reg),%reg" - Loc[-2] = 0x8d; - Loc[-1] = 0x80 | (Reg << 3) | Reg; - } - } - write32le(Loc, Val); -} - -void X86TargetInfo::relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - if (Type == R_386_TLS_LDO_32) { - write32le(Loc, Val); - return; - } - - // Convert - // leal foo(%reg),%eax - // call ___tls_get_addr - // to - // movl %gs:0,%eax - // nop - // leal 0(%esi,1),%esi - const uint8_t Inst[] = { - 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, // movl %gs:0,%eax - 0x90, // nop - 0x8d, 0x74, 0x26, 0x00 // leal 0(%esi,1),%esi - }; - memcpy(Loc - 2, Inst, sizeof(Inst)); -} - -template X86_64TargetInfo::X86_64TargetInfo() { - CopyRel = R_X86_64_COPY; - GotRel = R_X86_64_GLOB_DAT; - PltRel = R_X86_64_JUMP_SLOT; - RelativeRel = R_X86_64_RELATIVE; - IRelativeRel = R_X86_64_IRELATIVE; - TlsGotRel = R_X86_64_TPOFF64; - TlsModuleIndexRel = R_X86_64_DTPMOD64; - TlsOffsetRel = R_X86_64_DTPOFF64; - GotEntrySize = 8; - GotPltEntrySize = 8; - PltEntrySize = 16; - PltHeaderSize = 16; - TlsGdRelaxSkip = 2; - // Align to the large page size (known as a superpage or huge page). - // FreeBSD automatically promotes large, superpage-aligned allocations. - DefaultImageBase = 0x200000; - // 0xCC is the "int3" (call debug exception handler) instruction. - TrapInstr = 0xcccccccc; -} - -template -RelExpr X86_64TargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - switch (Type) { - case R_X86_64_8: - case R_X86_64_16: - case R_X86_64_32: - case R_X86_64_32S: - case R_X86_64_64: - case R_X86_64_DTPOFF32: - case R_X86_64_DTPOFF64: - return R_ABS; - case R_X86_64_TPOFF32: - return R_TLS; - case R_X86_64_TLSLD: - return R_TLSLD_PC; - case R_X86_64_TLSGD: - return R_TLSGD_PC; - case R_X86_64_SIZE32: - case R_X86_64_SIZE64: - return R_SIZE; - case R_X86_64_PLT32: - return R_PLT_PC; - case R_X86_64_PC32: - case R_X86_64_PC64: - return R_PC; - case R_X86_64_GOT32: - case R_X86_64_GOT64: - return R_GOT_FROM_END; - case R_X86_64_GOTPCREL: - case R_X86_64_GOTPCRELX: - case R_X86_64_REX_GOTPCRELX: - case R_X86_64_GOTTPOFF: - return R_GOT_PC; - case R_X86_64_NONE: - return R_NONE; - default: - error(toString(S.File) + ": unknown relocation type: " + toString(Type)); - return R_HINT; - } -} - -template -void X86_64TargetInfo::writeGotPltHeader(uint8_t *Buf) const { - // The first entry holds the value of _DYNAMIC. It is not clear why that is - // required, but it is documented in the psabi and the glibc dynamic linker - // seems to use it (note that this is relevant for linking ld.so, not any - // other program). - write64le(Buf, InX::Dynamic->getVA()); -} - -template -void X86_64TargetInfo::writeGotPlt(uint8_t *Buf, - const SymbolBody &S) const { - // See comments in X86TargetInfo::writeGotPlt. - write32le(Buf, S.getPltVA() + 6); -} - -template -void X86_64TargetInfo::writePltHeader(uint8_t *Buf) const { - const uint8_t PltData[] = { - 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, // pushq GOTPLT+8(%rip) - 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp *GOTPLT+16(%rip) - 0x0f, 0x1f, 0x40, 0x00 // nop - }; - memcpy(Buf, PltData, sizeof(PltData)); - uint64_t GotPlt = InX::GotPlt->getVA(); - uint64_t Plt = InX::Plt->getVA(); - write32le(Buf + 2, GotPlt - Plt + 2); // GOTPLT+8 - write32le(Buf + 8, GotPlt - Plt + 4); // GOTPLT+16 -} - -template -void X86_64TargetInfo::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, - 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 - 0xe9, 0x00, 0x00, 0x00, 0x00 // jmpq plt[0] - }; - memcpy(Buf, Inst, sizeof(Inst)); - - write32le(Buf + 2, GotPltEntryAddr - PltEntryAddr - 6); - write32le(Buf + 7, Index); - write32le(Buf + 12, -Index * PltEntrySize - PltHeaderSize - 16); -} - -template -bool X86_64TargetInfo::isPicRel(uint32_t Type) const { - return Type != R_X86_64_PC32 && Type != R_X86_64_32 && - Type != R_X86_64_TPOFF32; -} - -template -void X86_64TargetInfo::relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // Convert - // .byte 0x66 - // leaq x@tlsgd(%rip), %rdi - // .word 0x6666 - // rex64 - // call __tls_get_addr@plt - // to - // mov %fs:0x0,%rax - // lea x@tpoff,%rax - const uint8_t Inst[] = { - 0x64, 0x48, 0x8b, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00, // mov %fs:0x0,%rax - 0x48, 0x8d, 0x80, 0x00, 0x00, 0x00, 0x00 // lea x@tpoff,%rax - }; - memcpy(Loc - 4, Inst, sizeof(Inst)); - - // The original code used a pc relative relocation and so we have to - // compensate for the -4 in had in the addend. - write32le(Loc + 8, Val + 4); -} - -template -void X86_64TargetInfo::relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // Convert - // .byte 0x66 - // leaq x@tlsgd(%rip), %rdi - // .word 0x6666 - // rex64 - // call __tls_get_addr@plt - // to - // mov %fs:0x0,%rax - // addq x@tpoff,%rax - const uint8_t Inst[] = { - 0x64, 0x48, 0x8b, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00, // mov %fs:0x0,%rax - 0x48, 0x03, 0x05, 0x00, 0x00, 0x00, 0x00 // addq x@tpoff,%rax - }; - memcpy(Loc - 4, Inst, sizeof(Inst)); - - // Both code sequences are PC relatives, but since we are moving the constant - // forward by 8 bytes we have to subtract the value by 8. - write32le(Loc + 8, Val - 8); -} - -// In some conditions, R_X86_64_GOTTPOFF relocation can be optimized to -// R_X86_64_TPOFF32 so that it does not use GOT. -template -void X86_64TargetInfo::relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - uint8_t *Inst = Loc - 3; - uint8_t Reg = Loc[-1] >> 3; - uint8_t *RegSlot = Loc - 1; - - // Note that ADD with RSP or R12 is converted to ADD instead of LEA - // because LEA with these registers needs 4 bytes to encode and thus - // wouldn't fit the space. - - if (memcmp(Inst, "\x48\x03\x25", 3) == 0) { - // "addq foo@gottpoff(%rip),%rsp" -> "addq $foo,%rsp" - memcpy(Inst, "\x48\x81\xc4", 3); - } else if (memcmp(Inst, "\x4c\x03\x25", 3) == 0) { - // "addq foo@gottpoff(%rip),%r12" -> "addq $foo,%r12" - memcpy(Inst, "\x49\x81\xc4", 3); - } else if (memcmp(Inst, "\x4c\x03", 2) == 0) { - // "addq foo@gottpoff(%rip),%r[8-15]" -> "leaq foo(%r[8-15]),%r[8-15]" - memcpy(Inst, "\x4d\x8d", 2); - *RegSlot = 0x80 | (Reg << 3) | Reg; - } else if (memcmp(Inst, "\x48\x03", 2) == 0) { - // "addq foo@gottpoff(%rip),%reg -> "leaq foo(%reg),%reg" - memcpy(Inst, "\x48\x8d", 2); - *RegSlot = 0x80 | (Reg << 3) | Reg; - } else if (memcmp(Inst, "\x4c\x8b", 2) == 0) { - // "movq foo@gottpoff(%rip),%r[8-15]" -> "movq $foo,%r[8-15]" - memcpy(Inst, "\x49\xc7", 2); - *RegSlot = 0xc0 | Reg; - } else if (memcmp(Inst, "\x48\x8b", 2) == 0) { - // "movq foo@gottpoff(%rip),%reg" -> "movq $foo,%reg" - memcpy(Inst, "\x48\xc7", 2); - *RegSlot = 0xc0 | Reg; - } else { - error(getErrorLocation(Loc - 3) + - "R_X86_64_GOTTPOFF must be used in MOVQ or ADDQ instructions only"); - } - - // The original code used a PC relative relocation. - // Need to compensate for the -4 it had in the addend. - write32le(Loc, Val + 4); -} - -template -void X86_64TargetInfo::relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // Convert - // leaq bar@tlsld(%rip), %rdi - // callq __tls_get_addr@PLT - // leaq bar@dtpoff(%rax), %rcx - // to - // .word 0x6666 - // .byte 0x66 - // mov %fs:0,%rax - // leaq bar@tpoff(%rax), %rcx - if (Type == R_X86_64_DTPOFF64) { - write64le(Loc, Val); - return; - } - if (Type == R_X86_64_DTPOFF32) { - write32le(Loc, Val); - return; - } - - const uint8_t Inst[] = { - 0x66, 0x66, // .word 0x6666 - 0x66, // .byte 0x66 - 0x64, 0x48, 0x8b, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00 // mov %fs:0,%rax - }; - memcpy(Loc - 3, Inst, sizeof(Inst)); -} - -template -void X86_64TargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - switch (Type) { - case R_X86_64_8: - checkUInt<8>(Loc, Val, Type); - *Loc = Val; - break; - case R_X86_64_16: - checkUInt<16>(Loc, Val, Type); - write16le(Loc, Val); - break; - case R_X86_64_32: - checkUInt<32>(Loc, Val, Type); - write32le(Loc, Val); - break; - case R_X86_64_32S: - case R_X86_64_TPOFF32: - case R_X86_64_GOT32: - case R_X86_64_GOTPCREL: - case R_X86_64_GOTPCRELX: - case R_X86_64_REX_GOTPCRELX: - case R_X86_64_PC32: - case R_X86_64_GOTTPOFF: - case R_X86_64_PLT32: - case R_X86_64_TLSGD: - case R_X86_64_TLSLD: - case R_X86_64_DTPOFF32: - case R_X86_64_SIZE32: - checkInt<32>(Loc, Val, Type); - write32le(Loc, Val); - break; - case R_X86_64_64: - case R_X86_64_DTPOFF64: - case R_X86_64_GLOB_DAT: - case R_X86_64_PC64: - case R_X86_64_SIZE64: - case R_X86_64_GOT64: - write64le(Loc, Val); - break; - default: - llvm_unreachable("unexpected relocation"); - } -} - -template -RelExpr X86_64TargetInfo::adjustRelaxExpr(uint32_t Type, - const uint8_t *Data, - RelExpr RelExpr) const { - if (Type != R_X86_64_GOTPCRELX && Type != R_X86_64_REX_GOTPCRELX) - return RelExpr; - const uint8_t Op = Data[-2]; - const uint8_t ModRm = Data[-1]; - - // FIXME: When PIC is disabled and foo is defined locally in the - // lower 32 bit address space, memory operand in mov can be converted into - // immediate operand. Otherwise, mov must be changed to lea. We support only - // latter relaxation at this moment. - if (Op == 0x8b) - return R_RELAX_GOT_PC; - - // Relax call and jmp. - if (Op == 0xff && (ModRm == 0x15 || ModRm == 0x25)) - return R_RELAX_GOT_PC; - - // Relaxation of test, adc, add, and, cmp, or, sbb, sub, xor. - // If PIC then no relaxation is available. - // We also don't relax test/binop instructions without REX byte, - // they are 32bit operations and not common to have. - assert(Type == R_X86_64_REX_GOTPCRELX); - return Config->Pic ? RelExpr : R_RELAX_GOT_PC_NOPIC; -} - -// A subset of relaxations can only be applied for no-PIC. This method -// handles such relaxations. Instructions encoding information was taken from: -// "Intel 64 and IA-32 Architectures Software Developer's Manual V2" -// (http://www.intel.com/content/dam/www/public/us/en/documents/manuals/ -// 64-ia-32-architectures-software-developer-instruction-set-reference-manual-325383.pdf) -template -void X86_64TargetInfo::relaxGotNoPic(uint8_t *Loc, uint64_t Val, - uint8_t Op, uint8_t ModRm) const { - const uint8_t Rex = Loc[-3]; - // Convert "test %reg, foo@GOTPCREL(%rip)" to "test $foo, %reg". - if (Op == 0x85) { - // See "TEST-Logical Compare" (4-428 Vol. 2B), - // TEST r/m64, r64 uses "full" ModR / M byte (no opcode extension). - - // ModR/M byte has form XX YYY ZZZ, where - // YYY is MODRM.reg(register 2), ZZZ is MODRM.rm(register 1). - // XX has different meanings: - // 00: The operand's memory address is in reg1. - // 01: The operand's memory address is reg1 + a byte-sized displacement. - // 10: The operand's memory address is reg1 + a word-sized displacement. - // 11: The operand is reg1 itself. - // If an instruction requires only one operand, the unused reg2 field - // holds extra opcode bits rather than a register code - // 0xC0 == 11 000 000 binary. - // 0x38 == 00 111 000 binary. - // We transfer reg2 to reg1 here as operand. - // See "2.1.3 ModR/M and SIB Bytes" (Vol. 2A 2-3). - Loc[-1] = 0xc0 | (ModRm & 0x38) >> 3; // ModR/M byte. - - // Change opcode from TEST r/m64, r64 to TEST r/m64, imm32 - // See "TEST-Logical Compare" (4-428 Vol. 2B). - Loc[-2] = 0xf7; - - // Move R bit to the B bit in REX byte. - // REX byte is encoded as 0100WRXB, where - // 0100 is 4bit fixed pattern. - // REX.W When 1, a 64-bit operand size is used. Otherwise, when 0, the - // default operand size is used (which is 32-bit for most but not all - // instructions). - // REX.R This 1-bit value is an extension to the MODRM.reg field. - // REX.X This 1-bit value is an extension to the SIB.index field. - // REX.B This 1-bit value is an extension to the MODRM.rm field or the - // SIB.base field. - // See "2.2.1.2 More on REX Prefix Fields " (2-8 Vol. 2A). - Loc[-3] = (Rex & ~0x4) | (Rex & 0x4) >> 2; - write32le(Loc, Val); - return; - } - - // If we are here then we need to relax the adc, add, and, cmp, or, sbb, sub - // or xor operations. - - // Convert "binop foo@GOTPCREL(%rip), %reg" to "binop $foo, %reg". - // Logic is close to one for test instruction above, but we also - // write opcode extension here, see below for details. - Loc[-1] = 0xc0 | (ModRm & 0x38) >> 3 | (Op & 0x3c); // ModR/M byte. - - // Primary opcode is 0x81, opcode extension is one of: - // 000b = ADD, 001b is OR, 010b is ADC, 011b is SBB, - // 100b is AND, 101b is SUB, 110b is XOR, 111b is CMP. - // This value was wrote to MODRM.reg in a line above. - // See "3.2 INSTRUCTIONS (A-M)" (Vol. 2A 3-15), - // "INSTRUCTION SET REFERENCE, N-Z" (Vol. 2B 4-1) for - // descriptions about each operation. - Loc[-2] = 0x81; - Loc[-3] = (Rex & ~0x4) | (Rex & 0x4) >> 2; - write32le(Loc, Val); -} - -template -void X86_64TargetInfo::relaxGot(uint8_t *Loc, uint64_t Val) const { - const uint8_t Op = Loc[-2]; - const uint8_t ModRm = Loc[-1]; - - // Convert "mov foo@GOTPCREL(%rip),%reg" to "lea foo(%rip),%reg". - if (Op == 0x8b) { - Loc[-2] = 0x8d; - write32le(Loc, Val); - return; - } - - if (Op != 0xff) { - // We are relaxing a rip relative to an absolute, so compensate - // for the old -4 addend. - assert(!Config->Pic); - relaxGotNoPic(Loc, Val + 4, Op, ModRm); - return; - } - - // Convert call/jmp instructions. - if (ModRm == 0x15) { - // ABI says we can convert "call *foo@GOTPCREL(%rip)" to "nop; call foo". - // Instead we convert to "addr32 call foo" where addr32 is an instruction - // prefix. That makes result expression to be a single instruction. - Loc[-2] = 0x67; // addr32 prefix - Loc[-1] = 0xe8; // call - write32le(Loc, Val); - return; - } - - // Convert "jmp *foo@GOTPCREL(%rip)" to "jmp foo; nop". - // jmp doesn't return, so it is fine to use nop here, it is just a stub. - assert(ModRm == 0x25); - Loc[-2] = 0xe9; // jmp - Loc[3] = 0x90; // nop - write32le(Loc - 1, Val + 1); -} - -// Relocation masks following the #lo(value), #hi(value), #ha(value), -// #higher(value), #highera(value), #highest(value), and #highesta(value) -// macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi -// document. -static uint16_t applyPPCLo(uint64_t V) { return V; } -static uint16_t applyPPCHi(uint64_t V) { return V >> 16; } -static uint16_t applyPPCHa(uint64_t V) { return (V + 0x8000) >> 16; } -static uint16_t applyPPCHigher(uint64_t V) { return V >> 32; } -static uint16_t applyPPCHighera(uint64_t V) { return (V + 0x8000) >> 32; } -static uint16_t applyPPCHighest(uint64_t V) { return V >> 48; } -static uint16_t applyPPCHighesta(uint64_t V) { return (V + 0x8000) >> 48; } - -PPCTargetInfo::PPCTargetInfo() {} - -void PPCTargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - switch (Type) { - case R_PPC_ADDR16_HA: - write16be(Loc, applyPPCHa(Val)); - break; - case R_PPC_ADDR16_LO: - write16be(Loc, applyPPCLo(Val)); - break; - case R_PPC_ADDR32: - case R_PPC_REL32: - write32be(Loc, Val); - break; - case R_PPC_REL24: - or32be(Loc, Val & 0x3FFFFFC); - break; - default: - error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); - } -} - -RelExpr PPCTargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - switch (Type) { - case R_PPC_REL24: - case R_PPC_REL32: - return R_PC; - default: - return R_ABS; - } -} - -PPC64TargetInfo::PPC64TargetInfo() { - PltRel = GotRel = R_PPC64_GLOB_DAT; - RelativeRel = R_PPC64_RELATIVE; - GotEntrySize = 8; - GotPltEntrySize = 8; - PltEntrySize = 32; - PltHeaderSize = 0; - - // We need 64K pages (at least under glibc/Linux, the loader won't - // set different permissions on a finer granularity than that). - DefaultMaxPageSize = 65536; - - // The PPC64 ELF ABI v1 spec, says: - // - // It is normally desirable to put segments with different characteristics - // in separate 256 Mbyte portions of the address space, to give the - // operating system full paging flexibility in the 64-bit address space. - // - // And because the lowest non-zero 256M boundary is 0x10000000, PPC64 linkers - // use 0x10000000 as the starting address. - DefaultImageBase = 0x10000000; -} - -static uint64_t PPC64TocOffset = 0x8000; - -uint64_t getPPC64TocBase() { - // The TOC consists of sections .got, .toc, .tocbss, .plt in that order. The - // TOC starts where the first of these sections starts. We always create a - // .got when we see a relocation that uses it, so for us the start is always - // the .got. - uint64_t TocVA = InX::Got->getVA(); - - // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000 - // thus permitting a full 64 Kbytes segment. Note that the glibc startup - // code (crt1.o) assumes that you can get from the TOC base to the - // start of the .toc section with only a single (signed) 16-bit relocation. - return TocVA + PPC64TocOffset; -} - -RelExpr PPC64TargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - switch (Type) { - default: - return R_ABS; - case R_PPC64_TOC16: - case R_PPC64_TOC16_DS: - case R_PPC64_TOC16_HA: - case R_PPC64_TOC16_HI: - case R_PPC64_TOC16_LO: - case R_PPC64_TOC16_LO_DS: - return R_GOTREL; - case R_PPC64_TOC: - return R_PPC_TOC; - case R_PPC64_REL24: - return R_PPC_PLT_OPD; - } -} - -void PPC64TargetInfo::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, - uint64_t PltEntryAddr, int32_t Index, - unsigned RelOff) const { - uint64_t Off = GotPltEntryAddr - getPPC64TocBase(); - - // FIXME: What we should do, in theory, is get the offset of the function - // descriptor in the .opd section, and use that as the offset from %r2 (the - // TOC-base pointer). Instead, we have the GOT-entry offset, and that will - // be a pointer to the function descriptor in the .opd section. Using - // this scheme is simpler, but requires an extra indirection per PLT dispatch. - - write32be(Buf, 0xf8410028); // std %r2, 40(%r1) - write32be(Buf + 4, 0x3d620000 | applyPPCHa(Off)); // addis %r11, %r2, X@ha - write32be(Buf + 8, 0xe98b0000 | applyPPCLo(Off)); // ld %r12, X@l(%r11) - write32be(Buf + 12, 0xe96c0000); // ld %r11,0(%r12) - write32be(Buf + 16, 0x7d6903a6); // mtctr %r11 - write32be(Buf + 20, 0xe84c0008); // ld %r2,8(%r12) - write32be(Buf + 24, 0xe96c0010); // ld %r11,16(%r12) - write32be(Buf + 28, 0x4e800420); // bctr -} - -static std::pair toAddr16Rel(uint32_t Type, uint64_t Val) { - uint64_t V = Val - PPC64TocOffset; - switch (Type) { - case R_PPC64_TOC16: - return {R_PPC64_ADDR16, V}; - case R_PPC64_TOC16_DS: - return {R_PPC64_ADDR16_DS, V}; - case R_PPC64_TOC16_HA: - return {R_PPC64_ADDR16_HA, V}; - case R_PPC64_TOC16_HI: - return {R_PPC64_ADDR16_HI, V}; - case R_PPC64_TOC16_LO: - return {R_PPC64_ADDR16_LO, V}; - case R_PPC64_TOC16_LO_DS: - return {R_PPC64_ADDR16_LO_DS, V}; - default: - return {Type, Val}; - } -} - -void PPC64TargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // For a TOC-relative relocation, proceed in terms of the corresponding - // ADDR16 relocation type. - std::tie(Type, Val) = toAddr16Rel(Type, Val); - - switch (Type) { - case R_PPC64_ADDR14: { - checkAlignment<4>(Loc, Val, Type); - // Preserve the AA/LK bits in the branch instruction - uint8_t AALK = Loc[3]; - write16be(Loc + 2, (AALK & 3) | (Val & 0xfffc)); - break; - } - case R_PPC64_ADDR16: - checkInt<16>(Loc, Val, Type); - write16be(Loc, Val); - break; - case R_PPC64_ADDR16_DS: - checkInt<16>(Loc, Val, Type); - write16be(Loc, (read16be(Loc) & 3) | (Val & ~3)); - break; - case R_PPC64_ADDR16_HA: - case R_PPC64_REL16_HA: - write16be(Loc, applyPPCHa(Val)); - break; - case R_PPC64_ADDR16_HI: - case R_PPC64_REL16_HI: - write16be(Loc, applyPPCHi(Val)); - break; - case R_PPC64_ADDR16_HIGHER: - write16be(Loc, applyPPCHigher(Val)); - break; - case R_PPC64_ADDR16_HIGHERA: - write16be(Loc, applyPPCHighera(Val)); - break; - case R_PPC64_ADDR16_HIGHEST: - write16be(Loc, applyPPCHighest(Val)); - break; - case R_PPC64_ADDR16_HIGHESTA: - write16be(Loc, applyPPCHighesta(Val)); - break; - case R_PPC64_ADDR16_LO: - write16be(Loc, applyPPCLo(Val)); - break; - case R_PPC64_ADDR16_LO_DS: - case R_PPC64_REL16_LO: - write16be(Loc, (read16be(Loc) & 3) | (applyPPCLo(Val) & ~3)); - break; - case R_PPC64_ADDR32: - case R_PPC64_REL32: - checkInt<32>(Loc, Val, Type); - write32be(Loc, Val); - break; - case R_PPC64_ADDR64: - case R_PPC64_REL64: - case R_PPC64_TOC: - write64be(Loc, Val); - break; - case R_PPC64_REL24: { - uint32_t Mask = 0x03FFFFFC; - checkInt<24>(Loc, Val, Type); - write32be(Loc, (read32be(Loc) & ~Mask) | (Val & Mask)); - break; - } - default: - error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); - } -} - -AArch64TargetInfo::AArch64TargetInfo() { - CopyRel = R_AARCH64_COPY; - RelativeRel = R_AARCH64_RELATIVE; - IRelativeRel = R_AARCH64_IRELATIVE; - GotRel = R_AARCH64_GLOB_DAT; - PltRel = R_AARCH64_JUMP_SLOT; - TlsDescRel = R_AARCH64_TLSDESC; - TlsGotRel = R_AARCH64_TLS_TPREL64; - GotEntrySize = 8; - GotPltEntrySize = 8; - PltEntrySize = 16; - PltHeaderSize = 32; - DefaultMaxPageSize = 65536; - - // It doesn't seem to be documented anywhere, but tls on aarch64 uses variant - // 1 of the tls structures and the tcb size is 16. - TcbSize = 16; -} - -RelExpr AArch64TargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - switch (Type) { - default: - return R_ABS; - case R_AARCH64_TLSDESC_ADR_PAGE21: - return R_TLSDESC_PAGE; - case R_AARCH64_TLSDESC_LD64_LO12: - case R_AARCH64_TLSDESC_ADD_LO12: - return R_TLSDESC; - case R_AARCH64_TLSDESC_CALL: - return R_TLSDESC_CALL; - case R_AARCH64_TLSLE_ADD_TPREL_HI12: - case R_AARCH64_TLSLE_ADD_TPREL_LO12_NC: - return R_TLS; - case R_AARCH64_CALL26: - case R_AARCH64_CONDBR19: - case R_AARCH64_JUMP26: - case R_AARCH64_TSTBR14: - return R_PLT_PC; - case R_AARCH64_PREL16: - case R_AARCH64_PREL32: - case R_AARCH64_PREL64: - case R_AARCH64_ADR_PREL_LO21: - return R_PC; - case R_AARCH64_ADR_PREL_PG_HI21: - return R_PAGE_PC; - case R_AARCH64_LD64_GOT_LO12_NC: - case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: - return R_GOT; - case R_AARCH64_ADR_GOT_PAGE: - case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21: - return R_GOT_PAGE_PC; - case R_AARCH64_NONE: - return R_NONE; - } -} - -RelExpr AArch64TargetInfo::adjustRelaxExpr(uint32_t Type, const uint8_t *Data, - RelExpr Expr) const { - if (Expr == R_RELAX_TLS_GD_TO_IE) { - if (Type == R_AARCH64_TLSDESC_ADR_PAGE21) - return R_RELAX_TLS_GD_TO_IE_PAGE_PC; - return R_RELAX_TLS_GD_TO_IE_ABS; - } - return Expr; -} - -bool AArch64TargetInfo::usesOnlyLowPageBits(uint32_t Type) const { - switch (Type) { - default: - return false; - case R_AARCH64_ADD_ABS_LO12_NC: - case R_AARCH64_LD64_GOT_LO12_NC: - case R_AARCH64_LDST128_ABS_LO12_NC: - case R_AARCH64_LDST16_ABS_LO12_NC: - case R_AARCH64_LDST32_ABS_LO12_NC: - case R_AARCH64_LDST64_ABS_LO12_NC: - case R_AARCH64_LDST8_ABS_LO12_NC: - case R_AARCH64_TLSDESC_ADD_LO12: - case R_AARCH64_TLSDESC_LD64_LO12: - case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: - return true; - } -} - -bool AArch64TargetInfo::isPicRel(uint32_t Type) const { - return Type == R_AARCH64_ABS32 || Type == R_AARCH64_ABS64; -} - -void AArch64TargetInfo::writeGotPlt(uint8_t *Buf, const SymbolBody &) const { - write64le(Buf, InX::Plt->getVA()); -} - -// Page(Expr) is the page address of the expression Expr, defined -// as (Expr & ~0xFFF). (This applies even if the machine page size -// supported by the platform has a different value.) -uint64_t getAArch64Page(uint64_t Expr) { - return Expr & (~static_cast(0xFFF)); -} - -void AArch64TargetInfo::writePltHeader(uint8_t *Buf) const { - const uint8_t PltData[] = { - 0xf0, 0x7b, 0xbf, 0xa9, // stp x16, x30, [sp,#-16]! - 0x10, 0x00, 0x00, 0x90, // adrp x16, Page(&(.plt.got[2])) - 0x11, 0x02, 0x40, 0xf9, // ldr x17, [x16, Offset(&(.plt.got[2]))] - 0x10, 0x02, 0x00, 0x91, // add x16, x16, Offset(&(.plt.got[2])) - 0x20, 0x02, 0x1f, 0xd6, // br x17 - 0x1f, 0x20, 0x03, 0xd5, // nop - 0x1f, 0x20, 0x03, 0xd5, // nop - 0x1f, 0x20, 0x03, 0xd5 // nop - }; - memcpy(Buf, PltData, sizeof(PltData)); - - uint64_t Got = InX::GotPlt->getVA(); - uint64_t Plt = InX::Plt->getVA(); - relocateOne(Buf + 4, R_AARCH64_ADR_PREL_PG_HI21, - getAArch64Page(Got + 16) - getAArch64Page(Plt + 4)); - relocateOne(Buf + 8, R_AARCH64_LDST64_ABS_LO12_NC, Got + 16); - relocateOne(Buf + 12, R_AARCH64_ADD_ABS_LO12_NC, Got + 16); -} - -void AArch64TargetInfo::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, - 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]))] - 0x10, 0x02, 0x00, 0x91, // add x16, x16, Offset(&(.plt.got[n])) - 0x20, 0x02, 0x1f, 0xd6 // br x17 - }; - memcpy(Buf, Inst, sizeof(Inst)); - - relocateOne(Buf, R_AARCH64_ADR_PREL_PG_HI21, - getAArch64Page(GotPltEntryAddr) - getAArch64Page(PltEntryAddr)); - relocateOne(Buf + 4, R_AARCH64_LDST64_ABS_LO12_NC, GotPltEntryAddr); - relocateOne(Buf + 8, R_AARCH64_ADD_ABS_LO12_NC, GotPltEntryAddr); -} - -static void write32AArch64Addr(uint8_t *L, uint64_t Imm) { - uint32_t ImmLo = (Imm & 0x3) << 29; - uint32_t ImmHi = (Imm & 0x1FFFFC) << 3; - uint64_t Mask = (0x3 << 29) | (0x1FFFFC << 3); - write32le(L, (read32le(L) & ~Mask) | ImmLo | ImmHi); -} - -// Return the bits [Start, End] from Val shifted Start bits. -// For instance, getBits(0xF0, 4, 8) returns 0xF. -static uint64_t getBits(uint64_t Val, int Start, int End) { - uint64_t Mask = ((uint64_t)1 << (End + 1 - Start)) - 1; - return (Val >> Start) & Mask; -} - -// Update the immediate field in a AARCH64 ldr, str, and add instruction. -static void or32AArch64Imm(uint8_t *L, uint64_t Imm) { - or32le(L, (Imm & 0xFFF) << 10); -} - -void AArch64TargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - switch (Type) { - case R_AARCH64_ABS16: - case R_AARCH64_PREL16: - checkIntUInt<16>(Loc, Val, Type); - write16le(Loc, Val); - break; - case R_AARCH64_ABS32: - case R_AARCH64_PREL32: - checkIntUInt<32>(Loc, Val, Type); - write32le(Loc, Val); - break; - case R_AARCH64_ABS64: - case R_AARCH64_GLOB_DAT: - case R_AARCH64_PREL64: - write64le(Loc, Val); - break; - case R_AARCH64_ADD_ABS_LO12_NC: - or32AArch64Imm(Loc, Val); - break; - case R_AARCH64_ADR_GOT_PAGE: - case R_AARCH64_ADR_PREL_PG_HI21: - case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21: - case R_AARCH64_TLSDESC_ADR_PAGE21: - checkInt<33>(Loc, Val, Type); - write32AArch64Addr(Loc, Val >> 12); - break; - case R_AARCH64_ADR_PREL_LO21: - checkInt<21>(Loc, Val, Type); - write32AArch64Addr(Loc, Val); - break; - case R_AARCH64_CALL26: - case R_AARCH64_JUMP26: - checkInt<28>(Loc, Val, Type); - or32le(Loc, (Val & 0x0FFFFFFC) >> 2); - break; - case R_AARCH64_CONDBR19: - checkInt<21>(Loc, Val, Type); - or32le(Loc, (Val & 0x1FFFFC) << 3); - break; - case R_AARCH64_LD64_GOT_LO12_NC: - case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: - case R_AARCH64_TLSDESC_LD64_LO12: - checkAlignment<8>(Loc, Val, Type); - or32le(Loc, (Val & 0xFF8) << 7); - break; - case R_AARCH64_LDST8_ABS_LO12_NC: - or32AArch64Imm(Loc, getBits(Val, 0, 11)); - break; - case R_AARCH64_LDST16_ABS_LO12_NC: - or32AArch64Imm(Loc, getBits(Val, 1, 11)); - break; - case R_AARCH64_LDST32_ABS_LO12_NC: - or32AArch64Imm(Loc, getBits(Val, 2, 11)); - break; - case R_AARCH64_LDST64_ABS_LO12_NC: - or32AArch64Imm(Loc, getBits(Val, 3, 11)); - break; - case R_AARCH64_LDST128_ABS_LO12_NC: - or32AArch64Imm(Loc, getBits(Val, 4, 11)); - break; - case R_AARCH64_MOVW_UABS_G0_NC: - or32le(Loc, (Val & 0xFFFF) << 5); - break; - case R_AARCH64_MOVW_UABS_G1_NC: - or32le(Loc, (Val & 0xFFFF0000) >> 11); - break; - case R_AARCH64_MOVW_UABS_G2_NC: - or32le(Loc, (Val & 0xFFFF00000000) >> 27); - break; - case R_AARCH64_MOVW_UABS_G3: - or32le(Loc, (Val & 0xFFFF000000000000) >> 43); - break; - case R_AARCH64_TSTBR14: - checkInt<16>(Loc, Val, Type); - or32le(Loc, (Val & 0xFFFC) << 3); - break; - case R_AARCH64_TLSLE_ADD_TPREL_HI12: - checkInt<24>(Loc, Val, Type); - or32AArch64Imm(Loc, Val >> 12); - break; - case R_AARCH64_TLSLE_ADD_TPREL_LO12_NC: - case R_AARCH64_TLSDESC_ADD_LO12: - or32AArch64Imm(Loc, Val); - break; - default: - error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); - } -} - -void AArch64TargetInfo::relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // TLSDESC Global-Dynamic relocation are in the form: - // adrp x0, :tlsdesc:v [R_AARCH64_TLSDESC_ADR_PAGE21] - // ldr x1, [x0, #:tlsdesc_lo12:v [R_AARCH64_TLSDESC_LD64_LO12] - // add x0, x0, :tlsdesc_los:v [R_AARCH64_TLSDESC_ADD_LO12] - // .tlsdesccall [R_AARCH64_TLSDESC_CALL] - // blr x1 - // And it can optimized to: - // movz x0, #0x0, lsl #16 - // movk x0, #0x10 - // nop - // nop - checkUInt<32>(Loc, Val, Type); - - switch (Type) { - case R_AARCH64_TLSDESC_ADD_LO12: - case R_AARCH64_TLSDESC_CALL: - write32le(Loc, 0xd503201f); // nop - return; - case R_AARCH64_TLSDESC_ADR_PAGE21: - write32le(Loc, 0xd2a00000 | (((Val >> 16) & 0xffff) << 5)); // movz - return; - case R_AARCH64_TLSDESC_LD64_LO12: - write32le(Loc, 0xf2800000 | ((Val & 0xffff) << 5)); // movk - return; - default: - llvm_unreachable("unsupported relocation for TLS GD to LE relaxation"); - } -} - -void AArch64TargetInfo::relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - // TLSDESC Global-Dynamic relocation are in the form: - // adrp x0, :tlsdesc:v [R_AARCH64_TLSDESC_ADR_PAGE21] - // ldr x1, [x0, #:tlsdesc_lo12:v [R_AARCH64_TLSDESC_LD64_LO12] - // add x0, x0, :tlsdesc_los:v [R_AARCH64_TLSDESC_ADD_LO12] - // .tlsdesccall [R_AARCH64_TLSDESC_CALL] - // blr x1 - // And it can optimized to: - // adrp x0, :gottprel:v - // ldr x0, [x0, :gottprel_lo12:v] - // nop - // nop - - switch (Type) { - case R_AARCH64_TLSDESC_ADD_LO12: - case R_AARCH64_TLSDESC_CALL: - write32le(Loc, 0xd503201f); // nop - break; - case R_AARCH64_TLSDESC_ADR_PAGE21: - write32le(Loc, 0x90000000); // adrp - relocateOne(Loc, R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21, Val); - break; - case R_AARCH64_TLSDESC_LD64_LO12: - write32le(Loc, 0xf9400000); // ldr - relocateOne(Loc, R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC, Val); - break; - default: - llvm_unreachable("unsupported relocation for TLS GD to LE relaxation"); - } -} - -void AArch64TargetInfo::relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - checkUInt<32>(Loc, Val, Type); - - if (Type == R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21) { - // Generate MOVZ. - uint32_t RegNo = read32le(Loc) & 0x1f; - write32le(Loc, (0xd2a00000 | RegNo) | (((Val >> 16) & 0xffff) << 5)); - return; - } - if (Type == R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC) { - // Generate MOVK. - uint32_t RegNo = read32le(Loc) & 0x1f; - write32le(Loc, (0xf2800000 | RegNo) | ((Val & 0xffff) << 5)); - return; - } - llvm_unreachable("invalid relocation for TLS IE to LE relaxation"); -} - -AMDGPUTargetInfo::AMDGPUTargetInfo() { - RelativeRel = R_AMDGPU_REL64; - GotRel = R_AMDGPU_ABS64; - GotEntrySize = 8; -} - -void AMDGPUTargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - switch (Type) { - case R_AMDGPU_ABS32: - case R_AMDGPU_GOTPCREL: - case R_AMDGPU_GOTPCREL32_LO: - case R_AMDGPU_REL32: - case R_AMDGPU_REL32_LO: - write32le(Loc, Val); - break; - case R_AMDGPU_ABS64: - write64le(Loc, Val); - break; - case R_AMDGPU_GOTPCREL32_HI: - case R_AMDGPU_REL32_HI: - write32le(Loc, Val >> 32); - break; - default: - error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); - } -} - -RelExpr AMDGPUTargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - switch (Type) { - case R_AMDGPU_ABS32: - case R_AMDGPU_ABS64: - return R_ABS; - case R_AMDGPU_REL32: - case R_AMDGPU_REL32_LO: - case R_AMDGPU_REL32_HI: - return R_PC; - case R_AMDGPU_GOTPCREL: - case R_AMDGPU_GOTPCREL32_LO: - case R_AMDGPU_GOTPCREL32_HI: - return R_GOT_PC; - default: - error(toString(S.File) + ": unknown relocation type: " + toString(Type)); - return R_HINT; - } -} - -ARMTargetInfo::ARMTargetInfo() { - CopyRel = R_ARM_COPY; - RelativeRel = R_ARM_RELATIVE; - IRelativeRel = R_ARM_IRELATIVE; - GotRel = R_ARM_GLOB_DAT; - PltRel = R_ARM_JUMP_SLOT; - TlsGotRel = R_ARM_TLS_TPOFF32; - TlsModuleIndexRel = R_ARM_TLS_DTPMOD32; - TlsOffsetRel = R_ARM_TLS_DTPOFF32; - GotEntrySize = 4; - GotPltEntrySize = 4; - PltEntrySize = 16; - PltHeaderSize = 20; - // ARM uses Variant 1 TLS - TcbSize = 8; - NeedsThunks = true; -} - -RelExpr ARMTargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - switch (Type) { - default: - return R_ABS; - case R_ARM_THM_JUMP11: - return R_PC; - case R_ARM_CALL: - case R_ARM_JUMP24: - case R_ARM_PC24: - case R_ARM_PLT32: - case R_ARM_PREL31: - case R_ARM_THM_JUMP19: - case R_ARM_THM_JUMP24: - case R_ARM_THM_CALL: - return R_PLT_PC; - case R_ARM_GOTOFF32: - // (S + A) - GOT_ORG - return R_GOTREL; - case R_ARM_GOT_BREL: - // GOT(S) + A - GOT_ORG - return R_GOT_OFF; - case R_ARM_GOT_PREL: - case R_ARM_TLS_IE32: - // GOT(S) + A - P - return R_GOT_PC; - case R_ARM_SBREL32: - return R_ARM_SBREL; - case R_ARM_TARGET1: - return Config->Target1Rel ? R_PC : R_ABS; - case R_ARM_TARGET2: - if (Config->Target2 == Target2Policy::Rel) - return R_PC; - if (Config->Target2 == Target2Policy::Abs) - return R_ABS; - return R_GOT_PC; - case R_ARM_TLS_GD32: - return R_TLSGD_PC; - case R_ARM_TLS_LDM32: - return R_TLSLD_PC; - case R_ARM_BASE_PREL: - // B(S) + A - P - // FIXME: currently B(S) assumed to be .got, this may not hold for all - // platforms. - return R_GOTONLY_PC; - case R_ARM_MOVW_PREL_NC: - case R_ARM_MOVT_PREL: - case R_ARM_REL32: - case R_ARM_THM_MOVW_PREL_NC: - case R_ARM_THM_MOVT_PREL: - return R_PC; - case R_ARM_NONE: - return R_NONE; - case R_ARM_TLS_LE32: - return R_TLS; - } -} - -bool ARMTargetInfo::isPicRel(uint32_t Type) const { - return (Type == R_ARM_TARGET1 && !Config->Target1Rel) || - (Type == R_ARM_ABS32); -} - -uint32_t ARMTargetInfo::getDynRel(uint32_t Type) const { - if (Type == R_ARM_TARGET1 && !Config->Target1Rel) - return R_ARM_ABS32; - if (Type == R_ARM_ABS32) - return Type; - // Keep it going with a dummy value so that we can find more reloc errors. - return R_ARM_ABS32; -} - -void ARMTargetInfo::writeGotPlt(uint8_t *Buf, const SymbolBody &) const { - write32le(Buf, InX::Plt->getVA()); -} - -void ARMTargetInfo::writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const { - // An ARM entry is the address of the ifunc resolver function. - write32le(Buf, S.getVA()); -} - -void ARMTargetInfo::writePltHeader(uint8_t *Buf) const { - const uint8_t PltData[] = { - 0x04, 0xe0, 0x2d, 0xe5, // str lr, [sp,#-4]! - 0x04, 0xe0, 0x9f, 0xe5, // ldr lr, L2 - 0x0e, 0xe0, 0x8f, 0xe0, // L1: add lr, pc, lr - 0x08, 0xf0, 0xbe, 0xe5, // ldr pc, [lr, #8] - 0x00, 0x00, 0x00, 0x00, // L2: .word &(.got.plt) - L1 - 8 - }; - memcpy(Buf, PltData, sizeof(PltData)); - uint64_t GotPlt = InX::GotPlt->getVA(); - uint64_t L1 = InX::Plt->getVA() + 8; - write32le(Buf + 16, GotPlt - L1 - 8); -} - -void ARMTargetInfo::addPltHeaderSymbols(InputSectionBase *ISD) const { - auto *IS = cast(ISD); - addSyntheticLocal("$a", STT_NOTYPE, 0, 0, IS); - addSyntheticLocal("$d", STT_NOTYPE, 16, 0, IS); -} - -void ARMTargetInfo::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, - uint64_t PltEntryAddr, int32_t Index, - unsigned RelOff) const { - // FIXME: Using simple code sequence with simple relocations. - // There is a more optimal sequence but it requires support for the group - // relocations. See ELF for the ARM Architecture Appendix A.3 - const uint8_t PltData[] = { - 0x04, 0xc0, 0x9f, 0xe5, // ldr ip, L2 - 0x0f, 0xc0, 0x8c, 0xe0, // L1: add ip, ip, pc - 0x00, 0xf0, 0x9c, 0xe5, // ldr pc, [ip] - 0x00, 0x00, 0x00, 0x00, // L2: .word Offset(&(.plt.got) - L1 - 8 - }; - memcpy(Buf, PltData, sizeof(PltData)); - uint64_t L1 = PltEntryAddr + 4; - write32le(Buf + 12, GotPltEntryAddr - L1 - 8); -} - -void ARMTargetInfo::addPltSymbols(InputSectionBase *ISD, uint64_t Off) const { - auto *IS = cast(ISD); - addSyntheticLocal("$a", STT_NOTYPE, Off, 0, IS); - addSyntheticLocal("$d", STT_NOTYPE, Off + 12, 0, IS); -} - -bool ARMTargetInfo::needsThunk(RelExpr Expr, uint32_t RelocType, - const InputFile *File, - const SymbolBody &S) const { - // If S is an undefined weak symbol in an executable we don't need a Thunk. - // In a DSO calls to undefined symbols, including weak ones get PLT entries - // which may need a thunk. - if (S.isUndefined() && !S.isLocal() && S.symbol()->isWeak() && - !Config->Shared) - return false; - // A state change from ARM to Thumb and vice versa must go through an - // interworking thunk if the relocation type is not R_ARM_CALL or - // R_ARM_THM_CALL. - switch (RelocType) { - case R_ARM_PC24: - case R_ARM_PLT32: - case R_ARM_JUMP24: - // Source is ARM, all PLT entries are ARM so no interworking required. - // Otherwise we need to interwork if Symbol has bit 0 set (Thumb). - if (Expr == R_PC && ((S.getVA() & 1) == 1)) - return true; - break; - case R_ARM_THM_JUMP19: - case R_ARM_THM_JUMP24: - // Source is Thumb, all PLT entries are ARM so interworking is required. - // Otherwise we need to interwork if Symbol has bit 0 clear (ARM). - if (Expr == R_PLT_PC || ((S.getVA() & 1) == 0)) - return true; - break; - } - return false; -} - -void ARMTargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - switch (Type) { - case R_ARM_ABS32: - case R_ARM_BASE_PREL: - case R_ARM_GLOB_DAT: - case R_ARM_GOTOFF32: - case R_ARM_GOT_BREL: - case R_ARM_GOT_PREL: - case R_ARM_REL32: - case R_ARM_RELATIVE: - case R_ARM_SBREL32: - case R_ARM_TARGET1: - case R_ARM_TARGET2: - case R_ARM_TLS_GD32: - case R_ARM_TLS_IE32: - case R_ARM_TLS_LDM32: - case R_ARM_TLS_LDO32: - case R_ARM_TLS_LE32: - case R_ARM_TLS_TPOFF32: - case R_ARM_TLS_DTPOFF32: - write32le(Loc, Val); - break; - case R_ARM_TLS_DTPMOD32: - write32le(Loc, 1); - break; - case R_ARM_PREL31: - checkInt<31>(Loc, Val, Type); - write32le(Loc, (read32le(Loc) & 0x80000000) | (Val & ~0x80000000)); - break; - case R_ARM_CALL: - // R_ARM_CALL is used for BL and BLX instructions, depending on the - // value of bit 0 of Val, we must select a BL or BLX instruction - if (Val & 1) { - // If bit 0 of Val is 1 the target is Thumb, we must select a BLX. - // The BLX encoding is 0xfa:H:imm24 where Val = imm24:H:'1' - checkInt<26>(Loc, Val, Type); - write32le(Loc, 0xfa000000 | // opcode - ((Val & 2) << 23) | // H - ((Val >> 2) & 0x00ffffff)); // imm24 - break; - } - if ((read32le(Loc) & 0xfe000000) == 0xfa000000) - // BLX (always unconditional) instruction to an ARM Target, select an - // unconditional BL. - write32le(Loc, 0xeb000000 | (read32le(Loc) & 0x00ffffff)); - // fall through as BL encoding is shared with B - LLVM_FALLTHROUGH; - case R_ARM_JUMP24: - case R_ARM_PC24: - case R_ARM_PLT32: - checkInt<26>(Loc, Val, Type); - write32le(Loc, (read32le(Loc) & ~0x00ffffff) | ((Val >> 2) & 0x00ffffff)); - break; - case R_ARM_THM_JUMP11: - checkInt<12>(Loc, Val, Type); - write16le(Loc, (read32le(Loc) & 0xf800) | ((Val >> 1) & 0x07ff)); - break; - case R_ARM_THM_JUMP19: - // Encoding T3: Val = S:J2:J1:imm6:imm11:0 - checkInt<21>(Loc, Val, Type); - write16le(Loc, - (read16le(Loc) & 0xfbc0) | // opcode cond - ((Val >> 10) & 0x0400) | // S - ((Val >> 12) & 0x003f)); // imm6 - write16le(Loc + 2, - 0x8000 | // opcode - ((Val >> 8) & 0x0800) | // J2 - ((Val >> 5) & 0x2000) | // J1 - ((Val >> 1) & 0x07ff)); // imm11 - break; - case R_ARM_THM_CALL: - // R_ARM_THM_CALL is used for BL and BLX instructions, depending on the - // value of bit 0 of Val, we must select a BL or BLX instruction - if ((Val & 1) == 0) { - // Ensure BLX destination is 4-byte aligned. As BLX instruction may - // only be two byte aligned. This must be done before overflow check - Val = alignTo(Val, 4); - } - // Bit 12 is 0 for BLX, 1 for BL - write16le(Loc + 2, (read16le(Loc + 2) & ~0x1000) | (Val & 1) << 12); - // Fall through as rest of encoding is the same as B.W - LLVM_FALLTHROUGH; - case R_ARM_THM_JUMP24: - // Encoding B T4, BL T1, BLX T2: Val = S:I1:I2:imm10:imm11:0 - // FIXME: Use of I1 and I2 require v6T2ops - checkInt<25>(Loc, Val, Type); - write16le(Loc, - 0xf000 | // opcode - ((Val >> 14) & 0x0400) | // S - ((Val >> 12) & 0x03ff)); // imm10 - write16le(Loc + 2, - (read16le(Loc + 2) & 0xd000) | // opcode - (((~(Val >> 10)) ^ (Val >> 11)) & 0x2000) | // J1 - (((~(Val >> 11)) ^ (Val >> 13)) & 0x0800) | // J2 - ((Val >> 1) & 0x07ff)); // imm11 - break; - case R_ARM_MOVW_ABS_NC: - case R_ARM_MOVW_PREL_NC: - write32le(Loc, (read32le(Loc) & ~0x000f0fff) | ((Val & 0xf000) << 4) | - (Val & 0x0fff)); - break; - case R_ARM_MOVT_ABS: - case R_ARM_MOVT_PREL: - checkInt<32>(Loc, Val, Type); - write32le(Loc, (read32le(Loc) & ~0x000f0fff) | - (((Val >> 16) & 0xf000) << 4) | ((Val >> 16) & 0xfff)); - break; - case R_ARM_THM_MOVT_ABS: - case R_ARM_THM_MOVT_PREL: - // Encoding T1: A = imm4:i:imm3:imm8 - checkInt<32>(Loc, Val, Type); - write16le(Loc, - 0xf2c0 | // opcode - ((Val >> 17) & 0x0400) | // i - ((Val >> 28) & 0x000f)); // imm4 - write16le(Loc + 2, - (read16le(Loc + 2) & 0x8f00) | // opcode - ((Val >> 12) & 0x7000) | // imm3 - ((Val >> 16) & 0x00ff)); // imm8 - break; - case R_ARM_THM_MOVW_ABS_NC: - case R_ARM_THM_MOVW_PREL_NC: - // Encoding T3: A = imm4:i:imm3:imm8 - write16le(Loc, - 0xf240 | // opcode - ((Val >> 1) & 0x0400) | // i - ((Val >> 12) & 0x000f)); // imm4 - write16le(Loc + 2, - (read16le(Loc + 2) & 0x8f00) | // opcode - ((Val << 4) & 0x7000) | // imm3 - (Val & 0x00ff)); // imm8 - break; - default: - error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); - } -} - -int64_t ARMTargetInfo::getImplicitAddend(const uint8_t *Buf, - uint32_t Type) const { - switch (Type) { - default: - return 0; - case R_ARM_ABS32: - case R_ARM_BASE_PREL: - case R_ARM_GOTOFF32: - case R_ARM_GOT_BREL: - case R_ARM_GOT_PREL: - case R_ARM_REL32: - case R_ARM_TARGET1: - case R_ARM_TARGET2: - case R_ARM_TLS_GD32: - case R_ARM_TLS_LDM32: - case R_ARM_TLS_LDO32: - case R_ARM_TLS_IE32: - case R_ARM_TLS_LE32: - return SignExtend64<32>(read32le(Buf)); - case R_ARM_PREL31: - return SignExtend64<31>(read32le(Buf)); - case R_ARM_CALL: - case R_ARM_JUMP24: - case R_ARM_PC24: - case R_ARM_PLT32: - return SignExtend64<26>(read32le(Buf) << 2); - case R_ARM_THM_JUMP11: - return SignExtend64<12>(read16le(Buf) << 1); - case R_ARM_THM_JUMP19: { - // Encoding T3: A = S:J2:J1:imm10:imm6:0 - uint16_t Hi = read16le(Buf); - uint16_t Lo = read16le(Buf + 2); - return SignExtend64<20>(((Hi & 0x0400) << 10) | // S - ((Lo & 0x0800) << 8) | // J2 - ((Lo & 0x2000) << 5) | // J1 - ((Hi & 0x003f) << 12) | // imm6 - ((Lo & 0x07ff) << 1)); // imm11:0 - } - case R_ARM_THM_CALL: - case R_ARM_THM_JUMP24: { - // Encoding B T4, BL T1, BLX T2: A = S:I1:I2:imm10:imm11:0 - // I1 = NOT(J1 EOR S), I2 = NOT(J2 EOR S) - // FIXME: I1 and I2 require v6T2ops - uint16_t Hi = read16le(Buf); - uint16_t Lo = read16le(Buf + 2); - return SignExtend64<24>(((Hi & 0x0400) << 14) | // S - (~((Lo ^ (Hi << 3)) << 10) & 0x00800000) | // I1 - (~((Lo ^ (Hi << 1)) << 11) & 0x00400000) | // I2 - ((Hi & 0x003ff) << 12) | // imm0 - ((Lo & 0x007ff) << 1)); // imm11:0 - } - // ELF for the ARM Architecture 4.6.1.1 the implicit addend for MOVW and - // MOVT is in the range -32768 <= A < 32768 - case R_ARM_MOVW_ABS_NC: - case R_ARM_MOVT_ABS: - case R_ARM_MOVW_PREL_NC: - case R_ARM_MOVT_PREL: { - uint64_t Val = read32le(Buf) & 0x000f0fff; - return SignExtend64<16>(((Val & 0x000f0000) >> 4) | (Val & 0x00fff)); - } - case R_ARM_THM_MOVW_ABS_NC: - case R_ARM_THM_MOVT_ABS: - case R_ARM_THM_MOVW_PREL_NC: - case R_ARM_THM_MOVT_PREL: { - // Encoding T3: A = imm4:i:imm3:imm8 - uint16_t Hi = read16le(Buf); - uint16_t Lo = read16le(Buf + 2); - return SignExtend64<16>(((Hi & 0x000f) << 12) | // imm4 - ((Hi & 0x0400) << 1) | // i - ((Lo & 0x7000) >> 4) | // imm3 - (Lo & 0x00ff)); // imm8 - } - } -} - -template MipsTargetInfo::MipsTargetInfo() { - GotPltHeaderEntriesNum = 2; - DefaultMaxPageSize = 65536; - GotEntrySize = sizeof(typename ELFT::uint); - GotPltEntrySize = sizeof(typename ELFT::uint); - PltEntrySize = 16; - PltHeaderSize = 32; - CopyRel = R_MIPS_COPY; - PltRel = R_MIPS_JUMP_SLOT; - NeedsThunks = true; - if (ELFT::Is64Bits) { - RelativeRel = (R_MIPS_64 << 8) | R_MIPS_REL32; - TlsGotRel = R_MIPS_TLS_TPREL64; - TlsModuleIndexRel = R_MIPS_TLS_DTPMOD64; - TlsOffsetRel = R_MIPS_TLS_DTPREL64; - } else { - RelativeRel = R_MIPS_REL32; - TlsGotRel = R_MIPS_TLS_TPREL32; - TlsModuleIndexRel = R_MIPS_TLS_DTPMOD32; - TlsOffsetRel = R_MIPS_TLS_DTPREL32; - } -} - -template -RelExpr MipsTargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S, - const uint8_t *Loc) const { - // See comment in the calculateMipsRelChain. - if (ELFT::Is64Bits || Config->MipsN32Abi) - Type &= 0xff; - switch (Type) { - default: - return R_ABS; - case R_MIPS_JALR: - return R_HINT; - case R_MIPS_GPREL16: - case R_MIPS_GPREL32: - return R_MIPS_GOTREL; - case R_MIPS_26: - return R_PLT; - case R_MIPS_HI16: - case R_MIPS_LO16: - // R_MIPS_HI16/R_MIPS_LO16 relocations against _gp_disp calculate - // offset between start of function and 'gp' value which by default - // equal to the start of .got section. In that case we consider these - // relocations as relative. - if (&S == ElfSym::MipsGpDisp) - return R_MIPS_GOT_GP_PC; - if (&S == ElfSym::MipsLocalGp) - return R_MIPS_GOT_GP; - LLVM_FALLTHROUGH; - case R_MIPS_GOT_OFST: - return R_ABS; - case R_MIPS_PC32: - case R_MIPS_PC16: - case R_MIPS_PC19_S2: - case R_MIPS_PC21_S2: - case R_MIPS_PC26_S2: - case R_MIPS_PCHI16: - case R_MIPS_PCLO16: - return R_PC; - case R_MIPS_GOT16: - if (S.isLocal()) - return R_MIPS_GOT_LOCAL_PAGE; - LLVM_FALLTHROUGH; - case R_MIPS_CALL16: - case R_MIPS_GOT_DISP: - case R_MIPS_TLS_GOTTPREL: - return R_MIPS_GOT_OFF; - case R_MIPS_CALL_HI16: - case R_MIPS_CALL_LO16: - case R_MIPS_GOT_HI16: - case R_MIPS_GOT_LO16: - return R_MIPS_GOT_OFF32; - case R_MIPS_GOT_PAGE: - return R_MIPS_GOT_LOCAL_PAGE; - case R_MIPS_TLS_GD: - return R_MIPS_TLSGD; - case R_MIPS_TLS_LDM: - return R_MIPS_TLSLD; - } -} - -template bool MipsTargetInfo::isPicRel(uint32_t Type) const { - return Type == R_MIPS_32 || Type == R_MIPS_64; -} - -template -uint32_t MipsTargetInfo::getDynRel(uint32_t Type) const { - return RelativeRel; -} - -template -void MipsTargetInfo::writeGotPlt(uint8_t *Buf, const SymbolBody &) const { - write32(Buf, InX::Plt->getVA()); -} - -template -static int64_t getPcRelocAddend(const uint8_t *Loc) { - uint32_t Instr = read32(Loc); - uint32_t Mask = 0xffffffff >> (32 - BSIZE); - return SignExtend64((Instr & Mask) << SHIFT); -} - -template -static void applyMipsPcReloc(uint8_t *Loc, uint32_t Type, uint64_t V) { - uint32_t Mask = 0xffffffff >> (32 - BSIZE); - uint32_t Instr = read32(Loc); - if (SHIFT > 0) - checkAlignment<(1 << SHIFT)>(Loc, V, Type); - checkInt(Loc, V, Type); - write32(Loc, (Instr & ~Mask) | ((V >> SHIFT) & Mask)); -} - -template static void writeMipsHi16(uint8_t *Loc, uint64_t V) { - uint32_t Instr = read32(Loc); - uint16_t Res = ((V + 0x8000) >> 16) & 0xffff; - write32(Loc, (Instr & 0xffff0000) | Res); -} - -template static void writeMipsHigher(uint8_t *Loc, uint64_t V) { - uint32_t Instr = read32(Loc); - uint16_t Res = ((V + 0x80008000) >> 32) & 0xffff; - write32(Loc, (Instr & 0xffff0000) | Res); -} - -template static void writeMipsHighest(uint8_t *Loc, uint64_t V) { - uint32_t Instr = read32(Loc); - uint16_t Res = ((V + 0x800080008000) >> 48) & 0xffff; - write32(Loc, (Instr & 0xffff0000) | Res); -} - -template static void writeMipsLo16(uint8_t *Loc, uint64_t V) { - uint32_t Instr = read32(Loc); - write32(Loc, (Instr & 0xffff0000) | (V & 0xffff)); -} - -template static bool isMipsR6() { - const auto &FirstObj = cast>(*Config->FirstElf); - uint32_t Arch = FirstObj.getObj().getHeader()->e_flags & EF_MIPS_ARCH; - return Arch == EF_MIPS_ARCH_32R6 || Arch == EF_MIPS_ARCH_64R6; -} - -template -void MipsTargetInfo::writePltHeader(uint8_t *Buf) const { - const endianness E = ELFT::TargetEndianness; - if (Config->MipsN32Abi) { - write32(Buf, 0x3c0e0000); // lui $14, %hi(&GOTPLT[0]) - write32(Buf + 4, 0x8dd90000); // lw $25, %lo(&GOTPLT[0])($14) - write32(Buf + 8, 0x25ce0000); // addiu $14, $14, %lo(&GOTPLT[0]) - write32(Buf + 12, 0x030ec023); // subu $24, $24, $14 - } else { - write32(Buf, 0x3c1c0000); // lui $28, %hi(&GOTPLT[0]) - write32(Buf + 4, 0x8f990000); // lw $25, %lo(&GOTPLT[0])($28) - write32(Buf + 8, 0x279c0000); // addiu $28, $28, %lo(&GOTPLT[0]) - write32(Buf + 12, 0x031cc023); // subu $24, $24, $28 - } - - write32(Buf + 16, 0x03e07825); // move $15, $31 - write32(Buf + 20, 0x0018c082); // srl $24, $24, 2 - write32(Buf + 24, 0x0320f809); // jalr $25 - write32(Buf + 28, 0x2718fffe); // subu $24, $24, 2 - - uint64_t GotPlt = InX::GotPlt->getVA(); - writeMipsHi16(Buf, GotPlt); - writeMipsLo16(Buf + 4, GotPlt); - writeMipsLo16(Buf + 8, GotPlt); -} - -template -void MipsTargetInfo::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, - uint64_t PltEntryAddr, int32_t Index, - unsigned RelOff) const { - const endianness E = ELFT::TargetEndianness; - write32(Buf, 0x3c0f0000); // lui $15, %hi(.got.plt entry) - write32(Buf + 4, 0x8df90000); // l[wd] $25, %lo(.got.plt entry)($15) - // jr $25 - write32(Buf + 8, isMipsR6() ? 0x03200009 : 0x03200008); - write32(Buf + 12, 0x25f80000); // addiu $24, $15, %lo(.got.plt entry) - writeMipsHi16(Buf, GotPltEntryAddr); - writeMipsLo16(Buf + 4, GotPltEntryAddr); - writeMipsLo16(Buf + 12, GotPltEntryAddr); -} - -template -bool MipsTargetInfo::needsThunk(RelExpr Expr, uint32_t Type, - const InputFile *File, - const SymbolBody &S) const { - // Any MIPS PIC code function is invoked with its address in register $t9. - // So if we have a branch instruction from non-PIC code to the PIC one - // we cannot make the jump directly and need to create a small stubs - // to save the target function address. - // See page 3-38 ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf - if (Type != R_MIPS_26) - return false; - auto *F = dyn_cast_or_null>(File); - if (!F) - return false; - // If current file has PIC code, LA25 stub is not required. - if (F->getObj().getHeader()->e_flags & EF_MIPS_PIC) - return false; - auto *D = dyn_cast(&S); - // LA25 is required if target file has PIC code - // or target symbol is a PIC symbol. - return D && D->isMipsPIC(); -} - -template -int64_t MipsTargetInfo::getImplicitAddend(const uint8_t *Buf, - uint32_t Type) const { - const endianness E = ELFT::TargetEndianness; - switch (Type) { - default: - return 0; - case R_MIPS_32: - case R_MIPS_GPREL32: - case R_MIPS_TLS_DTPREL32: - case R_MIPS_TLS_TPREL32: - return SignExtend64<32>(read32(Buf)); - case R_MIPS_26: - // FIXME (simon): If the relocation target symbol is not a PLT entry - // we should use another expression for calculation: - // ((A << 2) | (P & 0xf0000000)) >> 2 - return SignExtend64<28>((read32(Buf) & 0x3ffffff) << 2); - case R_MIPS_GPREL16: - case R_MIPS_LO16: - case R_MIPS_PCLO16: - case R_MIPS_TLS_DTPREL_HI16: - case R_MIPS_TLS_DTPREL_LO16: - case R_MIPS_TLS_TPREL_HI16: - case R_MIPS_TLS_TPREL_LO16: - return SignExtend64<16>(read32(Buf)); - case R_MIPS_PC16: - return getPcRelocAddend(Buf); - case R_MIPS_PC19_S2: - return getPcRelocAddend(Buf); - case R_MIPS_PC21_S2: - return getPcRelocAddend(Buf); - case R_MIPS_PC26_S2: - return getPcRelocAddend(Buf); - case R_MIPS_PC32: - return getPcRelocAddend(Buf); - } -} - -static std::pair -calculateMipsRelChain(uint8_t *Loc, uint32_t Type, uint64_t Val) { - // MIPS N64 ABI packs multiple relocations into the single relocation - // record. In general, all up to three relocations can have arbitrary - // types. In fact, Clang and GCC uses only a few combinations. For now, - // we support two of them. That is allow to pass at least all LLVM - // test suite cases. - // / R_MIPS_SUB / R_MIPS_HI16 | R_MIPS_LO16 - // / R_MIPS_64 / R_MIPS_NONE - // The first relocation is a 'real' relocation which is calculated - // using the corresponding symbol's value. The second and the third - // relocations used to modify result of the first one: extend it to - // 64-bit, extract high or low part etc. For details, see part 2.9 Relocation - // at the https://dmz-portal.mips.com/mw/images/8/82/007-4658-001.pdf - uint32_t Type2 = (Type >> 8) & 0xff; - uint32_t Type3 = (Type >> 16) & 0xff; - if (Type2 == R_MIPS_NONE && Type3 == R_MIPS_NONE) - return std::make_pair(Type, Val); - if (Type2 == R_MIPS_64 && Type3 == R_MIPS_NONE) - return std::make_pair(Type2, Val); - if (Type2 == R_MIPS_SUB && (Type3 == R_MIPS_HI16 || Type3 == R_MIPS_LO16)) - return std::make_pair(Type3, -Val); - error(getErrorLocation(Loc) + "unsupported relocations combination " + - Twine(Type)); - return std::make_pair(Type & 0xff, Val); -} - -template -void MipsTargetInfo::relocateOne(uint8_t *Loc, uint32_t Type, - uint64_t Val) const { - const endianness E = ELFT::TargetEndianness; - // Thread pointer and DRP offsets from the start of TLS data area. - // https://www.linux-mips.org/wiki/NPTL - if (Type == R_MIPS_TLS_DTPREL_HI16 || Type == R_MIPS_TLS_DTPREL_LO16 || - Type == R_MIPS_TLS_DTPREL32 || Type == R_MIPS_TLS_DTPREL64) - Val -= 0x8000; - else if (Type == R_MIPS_TLS_TPREL_HI16 || Type == R_MIPS_TLS_TPREL_LO16 || - Type == R_MIPS_TLS_TPREL32 || Type == R_MIPS_TLS_TPREL64) - Val -= 0x7000; - if (ELFT::Is64Bits || Config->MipsN32Abi) - std::tie(Type, Val) = calculateMipsRelChain(Loc, Type, Val); - switch (Type) { - case R_MIPS_32: - case R_MIPS_GPREL32: - case R_MIPS_TLS_DTPREL32: - case R_MIPS_TLS_TPREL32: - write32(Loc, Val); - break; - case R_MIPS_64: - case R_MIPS_TLS_DTPREL64: - case R_MIPS_TLS_TPREL64: - write64(Loc, Val); - break; - case R_MIPS_26: - write32(Loc, (read32(Loc) & ~0x3ffffff) | ((Val >> 2) & 0x3ffffff)); - break; - case R_MIPS_GOT16: - // The R_MIPS_GOT16 relocation's value in "relocatable" linking mode - // is updated addend (not a GOT index). In that case write high 16 bits - // to store a correct addend value. - if (Config->Relocatable) - writeMipsHi16(Loc, Val); - else { - checkInt<16>(Loc, Val, Type); - writeMipsLo16(Loc, Val); - } - break; - case R_MIPS_GOT_DISP: - case R_MIPS_GOT_PAGE: - case R_MIPS_GPREL16: - case R_MIPS_TLS_GD: - case R_MIPS_TLS_LDM: - checkInt<16>(Loc, Val, Type); - LLVM_FALLTHROUGH; - case R_MIPS_CALL16: - case R_MIPS_CALL_LO16: - case R_MIPS_GOT_LO16: - case R_MIPS_GOT_OFST: - case R_MIPS_LO16: - case R_MIPS_PCLO16: - case R_MIPS_TLS_DTPREL_LO16: - case R_MIPS_TLS_GOTTPREL: - case R_MIPS_TLS_TPREL_LO16: - writeMipsLo16(Loc, Val); - break; - case R_MIPS_CALL_HI16: - case R_MIPS_GOT_HI16: - case R_MIPS_HI16: - case R_MIPS_PCHI16: - case R_MIPS_TLS_DTPREL_HI16: - case R_MIPS_TLS_TPREL_HI16: - writeMipsHi16(Loc, Val); - break; - case R_MIPS_HIGHER: - writeMipsHigher(Loc, Val); - break; - case R_MIPS_HIGHEST: - writeMipsHighest(Loc, Val); - break; - case R_MIPS_JALR: - // Ignore this optimization relocation for now - break; - case R_MIPS_PC16: - applyMipsPcReloc(Loc, Type, Val); - break; - case R_MIPS_PC19_S2: - applyMipsPcReloc(Loc, Type, Val); - break; - case R_MIPS_PC21_S2: - applyMipsPcReloc(Loc, Type, Val); - break; - case R_MIPS_PC26_S2: - applyMipsPcReloc(Loc, Type, Val); - break; - case R_MIPS_PC32: - applyMipsPcReloc(Loc, Type, Val); - break; - default: - error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); - } -} - -template -bool MipsTargetInfo::usesOnlyLowPageBits(uint32_t Type) const { - return Type == R_MIPS_LO16 || Type == R_MIPS_GOT_OFST; -} -} -} Index: lld/ELF/arch/AArch64.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/AArch64.cpp @@ -0,0 +1,374 @@ +//===- AArch64.cpp --------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "Memory.h" +#include "Symbols.h" +#include "SyntheticSections.h" +#include "Target.h" +#include "Thunks.h" +#include "llvm/Object/ELF.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +// Page(Expr) is the page address of the expression Expr, defined +// as (Expr & ~0xFFF). (This applies even if the machine page size +// supported by the platform has a different value.) +uint64_t elf::getAArch64Page(uint64_t Expr) { + return Expr & ~static_cast(0xFFF); +} + +namespace { +class AArch64 final : public TargetInfo { +public: + AArch64(); + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; + bool isPicRel(uint32_t Type) const override; + void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; + void writePltHeader(uint8_t *Buf) const override; + void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, + int32_t Index, unsigned RelOff) const override; + bool usesOnlyLowPageBits(uint32_t Type) const override; + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + RelExpr adjustRelaxExpr(uint32_t Type, const uint8_t *Data, + RelExpr Expr) const override; + void relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; +}; +} // namespace + +AArch64::AArch64() { + CopyRel = R_AARCH64_COPY; + RelativeRel = R_AARCH64_RELATIVE; + IRelativeRel = R_AARCH64_IRELATIVE; + GotRel = R_AARCH64_GLOB_DAT; + PltRel = R_AARCH64_JUMP_SLOT; + TlsDescRel = R_AARCH64_TLSDESC; + TlsGotRel = R_AARCH64_TLS_TPREL64; + GotEntrySize = 8; + GotPltEntrySize = 8; + PltEntrySize = 16; + PltHeaderSize = 32; + DefaultMaxPageSize = 65536; + + // It doesn't seem to be documented anywhere, but tls on aarch64 uses variant + // 1 of the tls structures and the tcb size is 16. + TcbSize = 16; +} + +RelExpr AArch64::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + switch (Type) { + default: + return R_ABS; + case R_AARCH64_TLSDESC_ADR_PAGE21: + return R_TLSDESC_PAGE; + case R_AARCH64_TLSDESC_LD64_LO12: + case R_AARCH64_TLSDESC_ADD_LO12: + return R_TLSDESC; + case R_AARCH64_TLSDESC_CALL: + return R_TLSDESC_CALL; + case R_AARCH64_TLSLE_ADD_TPREL_HI12: + case R_AARCH64_TLSLE_ADD_TPREL_LO12_NC: + return R_TLS; + case R_AARCH64_CALL26: + case R_AARCH64_CONDBR19: + case R_AARCH64_JUMP26: + case R_AARCH64_TSTBR14: + return R_PLT_PC; + case R_AARCH64_PREL16: + case R_AARCH64_PREL32: + case R_AARCH64_PREL64: + case R_AARCH64_ADR_PREL_LO21: + return R_PC; + case R_AARCH64_ADR_PREL_PG_HI21: + return R_PAGE_PC; + case R_AARCH64_LD64_GOT_LO12_NC: + case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: + return R_GOT; + case R_AARCH64_ADR_GOT_PAGE: + case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21: + return R_GOT_PAGE_PC; + case R_AARCH64_NONE: + return R_NONE; + } +} + +RelExpr AArch64::adjustRelaxExpr(uint32_t Type, const uint8_t *Data, + RelExpr Expr) const { + if (Expr == R_RELAX_TLS_GD_TO_IE) { + if (Type == R_AARCH64_TLSDESC_ADR_PAGE21) + return R_RELAX_TLS_GD_TO_IE_PAGE_PC; + return R_RELAX_TLS_GD_TO_IE_ABS; + } + return Expr; +} + +bool AArch64::usesOnlyLowPageBits(uint32_t Type) const { + switch (Type) { + default: + return false; + case R_AARCH64_ADD_ABS_LO12_NC: + case R_AARCH64_LD64_GOT_LO12_NC: + case R_AARCH64_LDST128_ABS_LO12_NC: + case R_AARCH64_LDST16_ABS_LO12_NC: + case R_AARCH64_LDST32_ABS_LO12_NC: + case R_AARCH64_LDST64_ABS_LO12_NC: + case R_AARCH64_LDST8_ABS_LO12_NC: + case R_AARCH64_TLSDESC_ADD_LO12: + case R_AARCH64_TLSDESC_LD64_LO12: + case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: + return true; + } +} + +bool AArch64::isPicRel(uint32_t Type) const { + return Type == R_AARCH64_ABS32 || Type == R_AARCH64_ABS64; +} + +void AArch64::writeGotPlt(uint8_t *Buf, const SymbolBody &) const { + write64le(Buf, InX::Plt->getVA()); +} + +void AArch64::writePltHeader(uint8_t *Buf) const { + const uint8_t PltData[] = { + 0xf0, 0x7b, 0xbf, 0xa9, // stp x16, x30, [sp,#-16]! + 0x10, 0x00, 0x00, 0x90, // adrp x16, Page(&(.plt.got[2])) + 0x11, 0x02, 0x40, 0xf9, // ldr x17, [x16, Offset(&(.plt.got[2]))] + 0x10, 0x02, 0x00, 0x91, // add x16, x16, Offset(&(.plt.got[2])) + 0x20, 0x02, 0x1f, 0xd6, // br x17 + 0x1f, 0x20, 0x03, 0xd5, // nop + 0x1f, 0x20, 0x03, 0xd5, // nop + 0x1f, 0x20, 0x03, 0xd5 // nop + }; + memcpy(Buf, PltData, sizeof(PltData)); + + uint64_t Got = InX::GotPlt->getVA(); + uint64_t Plt = InX::Plt->getVA(); + relocateOne(Buf + 4, R_AARCH64_ADR_PREL_PG_HI21, + getAArch64Page(Got + 16) - getAArch64Page(Plt + 4)); + relocateOne(Buf + 8, R_AARCH64_LDST64_ABS_LO12_NC, Got + 16); + relocateOne(Buf + 12, R_AARCH64_ADD_ABS_LO12_NC, Got + 16); +} + +void AArch64::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, + 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]))] + 0x10, 0x02, 0x00, 0x91, // add x16, x16, Offset(&(.plt.got[n])) + 0x20, 0x02, 0x1f, 0xd6 // br x17 + }; + memcpy(Buf, Inst, sizeof(Inst)); + + relocateOne(Buf, R_AARCH64_ADR_PREL_PG_HI21, + getAArch64Page(GotPltEntryAddr) - getAArch64Page(PltEntryAddr)); + relocateOne(Buf + 4, R_AARCH64_LDST64_ABS_LO12_NC, GotPltEntryAddr); + relocateOne(Buf + 8, R_AARCH64_ADD_ABS_LO12_NC, GotPltEntryAddr); +} + +static void write32AArch64Addr(uint8_t *L, uint64_t Imm) { + uint32_t ImmLo = (Imm & 0x3) << 29; + uint32_t ImmHi = (Imm & 0x1FFFFC) << 3; + uint64_t Mask = (0x3 << 29) | (0x1FFFFC << 3); + write32le(L, (read32le(L) & ~Mask) | ImmLo | ImmHi); +} + +// Return the bits [Start, End] from Val shifted Start bits. +// For instance, getBits(0xF0, 4, 8) returns 0xF. +static uint64_t getBits(uint64_t Val, int Start, int End) { + uint64_t Mask = ((uint64_t)1 << (End + 1 - Start)) - 1; + return (Val >> Start) & Mask; +} + +static void or32le(uint8_t *P, int32_t V) { write32le(P, read32le(P) | V); } + +// Update the immediate field in a AARCH64 ldr, str, and add instruction. +static void or32AArch64Imm(uint8_t *L, uint64_t Imm) { + or32le(L, (Imm & 0xFFF) << 10); +} + +void AArch64::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + switch (Type) { + case R_AARCH64_ABS16: + case R_AARCH64_PREL16: + checkIntUInt<16>(Loc, Val, Type); + write16le(Loc, Val); + break; + case R_AARCH64_ABS32: + case R_AARCH64_PREL32: + checkIntUInt<32>(Loc, Val, Type); + write32le(Loc, Val); + break; + case R_AARCH64_ABS64: + case R_AARCH64_GLOB_DAT: + case R_AARCH64_PREL64: + write64le(Loc, Val); + break; + case R_AARCH64_ADD_ABS_LO12_NC: + or32AArch64Imm(Loc, Val); + break; + case R_AARCH64_ADR_GOT_PAGE: + case R_AARCH64_ADR_PREL_PG_HI21: + case R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21: + case R_AARCH64_TLSDESC_ADR_PAGE21: + checkInt<33>(Loc, Val, Type); + write32AArch64Addr(Loc, Val >> 12); + break; + case R_AARCH64_ADR_PREL_LO21: + checkInt<21>(Loc, Val, Type); + write32AArch64Addr(Loc, Val); + break; + case R_AARCH64_CALL26: + case R_AARCH64_JUMP26: + checkInt<28>(Loc, Val, Type); + or32le(Loc, (Val & 0x0FFFFFFC) >> 2); + break; + case R_AARCH64_CONDBR19: + checkInt<21>(Loc, Val, Type); + or32le(Loc, (Val & 0x1FFFFC) << 3); + break; + case R_AARCH64_LD64_GOT_LO12_NC: + case R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: + case R_AARCH64_TLSDESC_LD64_LO12: + checkAlignment<8>(Loc, Val, Type); + or32le(Loc, (Val & 0xFF8) << 7); + break; + case R_AARCH64_LDST8_ABS_LO12_NC: + or32AArch64Imm(Loc, getBits(Val, 0, 11)); + break; + case R_AARCH64_LDST16_ABS_LO12_NC: + or32AArch64Imm(Loc, getBits(Val, 1, 11)); + break; + case R_AARCH64_LDST32_ABS_LO12_NC: + or32AArch64Imm(Loc, getBits(Val, 2, 11)); + break; + case R_AARCH64_LDST64_ABS_LO12_NC: + or32AArch64Imm(Loc, getBits(Val, 3, 11)); + break; + case R_AARCH64_LDST128_ABS_LO12_NC: + or32AArch64Imm(Loc, getBits(Val, 4, 11)); + break; + case R_AARCH64_MOVW_UABS_G0_NC: + or32le(Loc, (Val & 0xFFFF) << 5); + break; + case R_AARCH64_MOVW_UABS_G1_NC: + or32le(Loc, (Val & 0xFFFF0000) >> 11); + break; + case R_AARCH64_MOVW_UABS_G2_NC: + or32le(Loc, (Val & 0xFFFF00000000) >> 27); + break; + case R_AARCH64_MOVW_UABS_G3: + or32le(Loc, (Val & 0xFFFF000000000000) >> 43); + break; + case R_AARCH64_TSTBR14: + checkInt<16>(Loc, Val, Type); + or32le(Loc, (Val & 0xFFFC) << 3); + break; + case R_AARCH64_TLSLE_ADD_TPREL_HI12: + checkInt<24>(Loc, Val, Type); + or32AArch64Imm(Loc, Val >> 12); + break; + case R_AARCH64_TLSLE_ADD_TPREL_LO12_NC: + case R_AARCH64_TLSDESC_ADD_LO12: + or32AArch64Imm(Loc, Val); + break; + default: + error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); + } +} + +void AArch64::relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + // TLSDESC Global-Dynamic relocation are in the form: + // adrp x0, :tlsdesc:v [R_AARCH64_TLSDESC_ADR_PAGE21] + // ldr x1, [x0, #:tlsdesc_lo12:v [R_AARCH64_TLSDESC_LD64_LO12] + // add x0, x0, :tlsdesc_los:v [R_AARCH64_TLSDESC_ADD_LO12] + // .tlsdesccall [R_AARCH64_TLSDESC_CALL] + // blr x1 + // And it can optimized to: + // movz x0, #0x0, lsl #16 + // movk x0, #0x10 + // nop + // nop + checkUInt<32>(Loc, Val, Type); + + switch (Type) { + case R_AARCH64_TLSDESC_ADD_LO12: + case R_AARCH64_TLSDESC_CALL: + write32le(Loc, 0xd503201f); // nop + return; + case R_AARCH64_TLSDESC_ADR_PAGE21: + write32le(Loc, 0xd2a00000 | (((Val >> 16) & 0xffff) << 5)); // movz + return; + case R_AARCH64_TLSDESC_LD64_LO12: + write32le(Loc, 0xf2800000 | ((Val & 0xffff) << 5)); // movk + return; + default: + llvm_unreachable("unsupported relocation for TLS GD to LE relaxation"); + } +} + +void AArch64::relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + // TLSDESC Global-Dynamic relocation are in the form: + // adrp x0, :tlsdesc:v [R_AARCH64_TLSDESC_ADR_PAGE21] + // ldr x1, [x0, #:tlsdesc_lo12:v [R_AARCH64_TLSDESC_LD64_LO12] + // add x0, x0, :tlsdesc_los:v [R_AARCH64_TLSDESC_ADD_LO12] + // .tlsdesccall [R_AARCH64_TLSDESC_CALL] + // blr x1 + // And it can optimized to: + // adrp x0, :gottprel:v + // ldr x0, [x0, :gottprel_lo12:v] + // nop + // nop + + switch (Type) { + case R_AARCH64_TLSDESC_ADD_LO12: + case R_AARCH64_TLSDESC_CALL: + write32le(Loc, 0xd503201f); // nop + break; + case R_AARCH64_TLSDESC_ADR_PAGE21: + write32le(Loc, 0x90000000); // adrp + relocateOne(Loc, R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21, Val); + break; + case R_AARCH64_TLSDESC_LD64_LO12: + write32le(Loc, 0xf9400000); // ldr + relocateOne(Loc, R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC, Val); + break; + default: + llvm_unreachable("unsupported relocation for TLS GD to LE relaxation"); + } +} + +void AArch64::relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + checkUInt<32>(Loc, Val, Type); + + if (Type == R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21) { + // Generate MOVZ. + uint32_t RegNo = read32le(Loc) & 0x1f; + write32le(Loc, (0xd2a00000 | RegNo) | (((Val >> 16) & 0xffff) << 5)); + return; + } + if (Type == R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC) { + // Generate MOVK. + uint32_t RegNo = read32le(Loc) & 0x1f; + write32le(Loc, (0xf2800000 | RegNo) | ((Val & 0xffff) << 5)); + return; + } + llvm_unreachable("invalid relocation for TLS IE to LE relaxation"); +} + +TargetInfo *elf::createAArch64TargetInfo() { return make(); } Index: lld/ELF/arch/AMDGPU.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/AMDGPU.cpp @@ -0,0 +1,82 @@ +//===- AMDGPU.cpp ---------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "InputFiles.h" +#include "Memory.h" +#include "Symbols.h" +#include "Target.h" +#include "llvm/Object/ELF.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::object; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +namespace { +class AMDGPU final : public TargetInfo { +public: + AMDGPU(); + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; +}; +} // namespace + +AMDGPU::AMDGPU() { + RelativeRel = R_AMDGPU_REL64; + GotRel = R_AMDGPU_ABS64; + GotEntrySize = 8; +} + +void AMDGPU::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + switch (Type) { + case R_AMDGPU_ABS32: + case R_AMDGPU_GOTPCREL: + case R_AMDGPU_GOTPCREL32_LO: + case R_AMDGPU_REL32: + case R_AMDGPU_REL32_LO: + write32le(Loc, Val); + break; + case R_AMDGPU_ABS64: + write64le(Loc, Val); + break; + case R_AMDGPU_GOTPCREL32_HI: + case R_AMDGPU_REL32_HI: + write32le(Loc, Val >> 32); + break; + default: + error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); + } +} + +RelExpr AMDGPU::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + switch (Type) { + case R_AMDGPU_ABS32: + case R_AMDGPU_ABS64: + return R_ABS; + case R_AMDGPU_REL32: + case R_AMDGPU_REL32_LO: + case R_AMDGPU_REL32_HI: + return R_PC; + case R_AMDGPU_GOTPCREL: + case R_AMDGPU_GOTPCREL32_LO: + case R_AMDGPU_GOTPCREL32_HI: + return R_GOT_PC; + default: + error(toString(S.File) + ": unknown relocation type: " + toString(Type)); + return R_HINT; + } +} + +TargetInfo *elf::createAMDGPUTargetInfo() { return make(); } Index: lld/ELF/arch/ARM.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/ARM.cpp @@ -0,0 +1,432 @@ +//===- ARM.cpp ------------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "InputFiles.h" +#include "Memory.h" +#include "Symbols.h" +#include "SyntheticSections.h" +#include "Target.h" +#include "Thunks.h" +#include "llvm/Object/ELF.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +namespace { +class ARM final : public TargetInfo { +public: + ARM(); + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; + bool isPicRel(uint32_t Type) const override; + uint32_t getDynRel(uint32_t Type) const override; + int64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const override; + void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; + void writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const override; + void writePltHeader(uint8_t *Buf) const override; + void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, + int32_t Index, unsigned RelOff) const override; + void addPltSymbols(InputSectionBase *IS, uint64_t Off) const override; + void addPltHeaderSymbols(InputSectionBase *ISD) const override; + bool needsThunk(RelExpr Expr, uint32_t RelocType, const InputFile *File, + const SymbolBody &S) const override; + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; +}; +} // namespace + +ARM::ARM() { + CopyRel = R_ARM_COPY; + RelativeRel = R_ARM_RELATIVE; + IRelativeRel = R_ARM_IRELATIVE; + GotRel = R_ARM_GLOB_DAT; + PltRel = R_ARM_JUMP_SLOT; + TlsGotRel = R_ARM_TLS_TPOFF32; + TlsModuleIndexRel = R_ARM_TLS_DTPMOD32; + TlsOffsetRel = R_ARM_TLS_DTPOFF32; + GotEntrySize = 4; + GotPltEntrySize = 4; + PltEntrySize = 16; + PltHeaderSize = 20; + // ARM uses Variant 1 TLS + TcbSize = 8; + NeedsThunks = true; +} + +RelExpr ARM::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + switch (Type) { + default: + return R_ABS; + case R_ARM_THM_JUMP11: + return R_PC; + case R_ARM_CALL: + case R_ARM_JUMP24: + case R_ARM_PC24: + case R_ARM_PLT32: + case R_ARM_PREL31: + case R_ARM_THM_JUMP19: + case R_ARM_THM_JUMP24: + case R_ARM_THM_CALL: + return R_PLT_PC; + case R_ARM_GOTOFF32: + // (S + A) - GOT_ORG + return R_GOTREL; + case R_ARM_GOT_BREL: + // GOT(S) + A - GOT_ORG + return R_GOT_OFF; + case R_ARM_GOT_PREL: + case R_ARM_TLS_IE32: + // GOT(S) + A - P + return R_GOT_PC; + case R_ARM_SBREL32: + return R_ARM_SBREL; + case R_ARM_TARGET1: + return Config->Target1Rel ? R_PC : R_ABS; + case R_ARM_TARGET2: + if (Config->Target2 == Target2Policy::Rel) + return R_PC; + if (Config->Target2 == Target2Policy::Abs) + return R_ABS; + return R_GOT_PC; + case R_ARM_TLS_GD32: + return R_TLSGD_PC; + case R_ARM_TLS_LDM32: + return R_TLSLD_PC; + case R_ARM_BASE_PREL: + // B(S) + A - P + // FIXME: currently B(S) assumed to be .got, this may not hold for all + // platforms. + return R_GOTONLY_PC; + case R_ARM_MOVW_PREL_NC: + case R_ARM_MOVT_PREL: + case R_ARM_REL32: + case R_ARM_THM_MOVW_PREL_NC: + case R_ARM_THM_MOVT_PREL: + return R_PC; + case R_ARM_NONE: + return R_NONE; + case R_ARM_TLS_LE32: + return R_TLS; + } +} + +bool ARM::isPicRel(uint32_t Type) const { + return (Type == R_ARM_TARGET1 && !Config->Target1Rel) || + (Type == R_ARM_ABS32); +} + +uint32_t ARM::getDynRel(uint32_t Type) const { + if (Type == R_ARM_TARGET1 && !Config->Target1Rel) + return R_ARM_ABS32; + if (Type == R_ARM_ABS32) + return Type; + // Keep it going with a dummy value so that we can find more reloc errors. + return R_ARM_ABS32; +} + +void ARM::writeGotPlt(uint8_t *Buf, const SymbolBody &) const { + write32le(Buf, InX::Plt->getVA()); +} + +void ARM::writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const { + // An ARM entry is the address of the ifunc resolver function. + write32le(Buf, S.getVA()); +} + +void ARM::writePltHeader(uint8_t *Buf) const { + const uint8_t PltData[] = { + 0x04, 0xe0, 0x2d, 0xe5, // str lr, [sp,#-4]! + 0x04, 0xe0, 0x9f, 0xe5, // ldr lr, L2 + 0x0e, 0xe0, 0x8f, 0xe0, // L1: add lr, pc, lr + 0x08, 0xf0, 0xbe, 0xe5, // ldr pc, [lr, #8] + 0x00, 0x00, 0x00, 0x00, // L2: .word &(.got.plt) - L1 - 8 + }; + memcpy(Buf, PltData, sizeof(PltData)); + uint64_t GotPlt = InX::GotPlt->getVA(); + uint64_t L1 = InX::Plt->getVA() + 8; + write32le(Buf + 16, GotPlt - L1 - 8); +} + +void ARM::addPltHeaderSymbols(InputSectionBase *ISD) const { + auto *IS = cast(ISD); + addSyntheticLocal("$a", STT_NOTYPE, 0, 0, IS); + addSyntheticLocal("$d", STT_NOTYPE, 16, 0, IS); +} + +void ARM::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const { + // FIXME: Using simple code sequence with simple relocations. + // There is a more optimal sequence but it requires support for the group + // relocations. See ELF for the ARM Architecture Appendix A.3 + const uint8_t PltData[] = { + 0x04, 0xc0, 0x9f, 0xe5, // ldr ip, L2 + 0x0f, 0xc0, 0x8c, 0xe0, // L1: add ip, ip, pc + 0x00, 0xf0, 0x9c, 0xe5, // ldr pc, [ip] + 0x00, 0x00, 0x00, 0x00, // L2: .word Offset(&(.plt.got) - L1 - 8 + }; + memcpy(Buf, PltData, sizeof(PltData)); + uint64_t L1 = PltEntryAddr + 4; + write32le(Buf + 12, GotPltEntryAddr - L1 - 8); +} + +void ARM::addPltSymbols(InputSectionBase *ISD, uint64_t Off) const { + auto *IS = cast(ISD); + addSyntheticLocal("$a", STT_NOTYPE, Off, 0, IS); + addSyntheticLocal("$d", STT_NOTYPE, Off + 12, 0, IS); +} + +bool ARM::needsThunk(RelExpr Expr, uint32_t RelocType, const InputFile *File, + const SymbolBody &S) const { + // If S is an undefined weak symbol in an executable we don't need a Thunk. + // In a DSO calls to undefined symbols, including weak ones get PLT entries + // which may need a thunk. + if (S.isUndefined() && !S.isLocal() && S.symbol()->isWeak() && + !Config->Shared) + return false; + // A state change from ARM to Thumb and vice versa must go through an + // interworking thunk if the relocation type is not R_ARM_CALL or + // R_ARM_THM_CALL. + switch (RelocType) { + case R_ARM_PC24: + case R_ARM_PLT32: + case R_ARM_JUMP24: + // Source is ARM, all PLT entries are ARM so no interworking required. + // Otherwise we need to interwork if Symbol has bit 0 set (Thumb). + if (Expr == R_PC && ((S.getVA() & 1) == 1)) + return true; + break; + case R_ARM_THM_JUMP19: + case R_ARM_THM_JUMP24: + // Source is Thumb, all PLT entries are ARM so interworking is required. + // Otherwise we need to interwork if Symbol has bit 0 clear (ARM). + if (Expr == R_PLT_PC || ((S.getVA() & 1) == 0)) + return true; + break; + } + return false; +} + +void ARM::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + switch (Type) { + case R_ARM_ABS32: + case R_ARM_BASE_PREL: + case R_ARM_GLOB_DAT: + case R_ARM_GOTOFF32: + case R_ARM_GOT_BREL: + case R_ARM_GOT_PREL: + case R_ARM_REL32: + case R_ARM_RELATIVE: + case R_ARM_SBREL32: + case R_ARM_TARGET1: + case R_ARM_TARGET2: + case R_ARM_TLS_GD32: + case R_ARM_TLS_IE32: + case R_ARM_TLS_LDM32: + case R_ARM_TLS_LDO32: + case R_ARM_TLS_LE32: + case R_ARM_TLS_TPOFF32: + case R_ARM_TLS_DTPOFF32: + write32le(Loc, Val); + break; + case R_ARM_TLS_DTPMOD32: + write32le(Loc, 1); + break; + case R_ARM_PREL31: + checkInt<31>(Loc, Val, Type); + write32le(Loc, (read32le(Loc) & 0x80000000) | (Val & ~0x80000000)); + break; + case R_ARM_CALL: + // R_ARM_CALL is used for BL and BLX instructions, depending on the + // value of bit 0 of Val, we must select a BL or BLX instruction + if (Val & 1) { + // If bit 0 of Val is 1 the target is Thumb, we must select a BLX. + // The BLX encoding is 0xfa:H:imm24 where Val = imm24:H:'1' + checkInt<26>(Loc, Val, Type); + write32le(Loc, 0xfa000000 | // opcode + ((Val & 2) << 23) | // H + ((Val >> 2) & 0x00ffffff)); // imm24 + break; + } + if ((read32le(Loc) & 0xfe000000) == 0xfa000000) + // BLX (always unconditional) instruction to an ARM Target, select an + // unconditional BL. + write32le(Loc, 0xeb000000 | (read32le(Loc) & 0x00ffffff)); + // fall through as BL encoding is shared with B + LLVM_FALLTHROUGH; + case R_ARM_JUMP24: + case R_ARM_PC24: + case R_ARM_PLT32: + checkInt<26>(Loc, Val, Type); + write32le(Loc, (read32le(Loc) & ~0x00ffffff) | ((Val >> 2) & 0x00ffffff)); + break; + case R_ARM_THM_JUMP11: + checkInt<12>(Loc, Val, Type); + write16le(Loc, (read32le(Loc) & 0xf800) | ((Val >> 1) & 0x07ff)); + break; + case R_ARM_THM_JUMP19: + // Encoding T3: Val = S:J2:J1:imm6:imm11:0 + checkInt<21>(Loc, Val, Type); + write16le(Loc, + (read16le(Loc) & 0xfbc0) | // opcode cond + ((Val >> 10) & 0x0400) | // S + ((Val >> 12) & 0x003f)); // imm6 + write16le(Loc + 2, + 0x8000 | // opcode + ((Val >> 8) & 0x0800) | // J2 + ((Val >> 5) & 0x2000) | // J1 + ((Val >> 1) & 0x07ff)); // imm11 + break; + case R_ARM_THM_CALL: + // R_ARM_THM_CALL is used for BL and BLX instructions, depending on the + // value of bit 0 of Val, we must select a BL or BLX instruction + if ((Val & 1) == 0) { + // Ensure BLX destination is 4-byte aligned. As BLX instruction may + // only be two byte aligned. This must be done before overflow check + Val = alignTo(Val, 4); + } + // Bit 12 is 0 for BLX, 1 for BL + write16le(Loc + 2, (read16le(Loc + 2) & ~0x1000) | (Val & 1) << 12); + // Fall through as rest of encoding is the same as B.W + LLVM_FALLTHROUGH; + case R_ARM_THM_JUMP24: + // Encoding B T4, BL T1, BLX T2: Val = S:I1:I2:imm10:imm11:0 + // FIXME: Use of I1 and I2 require v6T2ops + checkInt<25>(Loc, Val, Type); + write16le(Loc, + 0xf000 | // opcode + ((Val >> 14) & 0x0400) | // S + ((Val >> 12) & 0x03ff)); // imm10 + write16le(Loc + 2, + (read16le(Loc + 2) & 0xd000) | // opcode + (((~(Val >> 10)) ^ (Val >> 11)) & 0x2000) | // J1 + (((~(Val >> 11)) ^ (Val >> 13)) & 0x0800) | // J2 + ((Val >> 1) & 0x07ff)); // imm11 + break; + case R_ARM_MOVW_ABS_NC: + case R_ARM_MOVW_PREL_NC: + write32le(Loc, (read32le(Loc) & ~0x000f0fff) | ((Val & 0xf000) << 4) | + (Val & 0x0fff)); + break; + case R_ARM_MOVT_ABS: + case R_ARM_MOVT_PREL: + checkInt<32>(Loc, Val, Type); + write32le(Loc, (read32le(Loc) & ~0x000f0fff) | + (((Val >> 16) & 0xf000) << 4) | ((Val >> 16) & 0xfff)); + break; + case R_ARM_THM_MOVT_ABS: + case R_ARM_THM_MOVT_PREL: + // Encoding T1: A = imm4:i:imm3:imm8 + checkInt<32>(Loc, Val, Type); + write16le(Loc, + 0xf2c0 | // opcode + ((Val >> 17) & 0x0400) | // i + ((Val >> 28) & 0x000f)); // imm4 + write16le(Loc + 2, + (read16le(Loc + 2) & 0x8f00) | // opcode + ((Val >> 12) & 0x7000) | // imm3 + ((Val >> 16) & 0x00ff)); // imm8 + break; + case R_ARM_THM_MOVW_ABS_NC: + case R_ARM_THM_MOVW_PREL_NC: + // Encoding T3: A = imm4:i:imm3:imm8 + write16le(Loc, + 0xf240 | // opcode + ((Val >> 1) & 0x0400) | // i + ((Val >> 12) & 0x000f)); // imm4 + write16le(Loc + 2, + (read16le(Loc + 2) & 0x8f00) | // opcode + ((Val << 4) & 0x7000) | // imm3 + (Val & 0x00ff)); // imm8 + break; + default: + error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); + } +} + +int64_t ARM::getImplicitAddend(const uint8_t *Buf, uint32_t Type) const { + switch (Type) { + default: + return 0; + case R_ARM_ABS32: + case R_ARM_BASE_PREL: + case R_ARM_GOTOFF32: + case R_ARM_GOT_BREL: + case R_ARM_GOT_PREL: + case R_ARM_REL32: + case R_ARM_TARGET1: + case R_ARM_TARGET2: + case R_ARM_TLS_GD32: + case R_ARM_TLS_LDM32: + case R_ARM_TLS_LDO32: + case R_ARM_TLS_IE32: + case R_ARM_TLS_LE32: + return SignExtend64<32>(read32le(Buf)); + case R_ARM_PREL31: + return SignExtend64<31>(read32le(Buf)); + case R_ARM_CALL: + case R_ARM_JUMP24: + case R_ARM_PC24: + case R_ARM_PLT32: + return SignExtend64<26>(read32le(Buf) << 2); + case R_ARM_THM_JUMP11: + return SignExtend64<12>(read16le(Buf) << 1); + case R_ARM_THM_JUMP19: { + // Encoding T3: A = S:J2:J1:imm10:imm6:0 + uint16_t Hi = read16le(Buf); + uint16_t Lo = read16le(Buf + 2); + return SignExtend64<20>(((Hi & 0x0400) << 10) | // S + ((Lo & 0x0800) << 8) | // J2 + ((Lo & 0x2000) << 5) | // J1 + ((Hi & 0x003f) << 12) | // imm6 + ((Lo & 0x07ff) << 1)); // imm11:0 + } + case R_ARM_THM_CALL: + case R_ARM_THM_JUMP24: { + // Encoding B T4, BL T1, BLX T2: A = S:I1:I2:imm10:imm11:0 + // I1 = NOT(J1 EOR S), I2 = NOT(J2 EOR S) + // FIXME: I1 and I2 require v6T2ops + uint16_t Hi = read16le(Buf); + uint16_t Lo = read16le(Buf + 2); + return SignExtend64<24>(((Hi & 0x0400) << 14) | // S + (~((Lo ^ (Hi << 3)) << 10) & 0x00800000) | // I1 + (~((Lo ^ (Hi << 1)) << 11) & 0x00400000) | // I2 + ((Hi & 0x003ff) << 12) | // imm0 + ((Lo & 0x007ff) << 1)); // imm11:0 + } + // ELF for the ARM Architecture 4.6.1.1 the implicit addend for MOVW and + // MOVT is in the range -32768 <= A < 32768 + case R_ARM_MOVW_ABS_NC: + case R_ARM_MOVT_ABS: + case R_ARM_MOVW_PREL_NC: + case R_ARM_MOVT_PREL: { + uint64_t Val = read32le(Buf) & 0x000f0fff; + return SignExtend64<16>(((Val & 0x000f0000) >> 4) | (Val & 0x00fff)); + } + case R_ARM_THM_MOVW_ABS_NC: + case R_ARM_THM_MOVT_ABS: + case R_ARM_THM_MOVW_PREL_NC: + case R_ARM_THM_MOVT_PREL: { + // Encoding T3: A = imm4:i:imm3:imm8 + uint16_t Hi = read16le(Buf); + uint16_t Lo = read16le(Buf + 2); + return SignExtend64<16>(((Hi & 0x000f) << 12) | // imm4 + ((Hi & 0x0400) << 1) | // i + ((Lo & 0x7000) >> 4) | // imm3 + (Lo & 0x00ff)); // imm8 + } + } +} + +TargetInfo *elf::createARMTargetInfo() { return make(); } Index: lld/ELF/arch/Mips.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/Mips.cpp @@ -0,0 +1,422 @@ +//===- MIPS.cpp -----------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "InputFiles.h" +#include "Memory.h" +#include "OutputSections.h" +#include "Symbols.h" +#include "SyntheticSections.h" +#include "Target.h" +#include "Thunks.h" +#include "llvm/Object/ELF.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::object; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +namespace { +template class MIPS final : public TargetInfo { +public: + MIPS(); + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; + int64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const override; + bool isPicRel(uint32_t Type) const override; + uint32_t getDynRel(uint32_t Type) const override; + void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; + void writePltHeader(uint8_t *Buf) const override; + void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, + int32_t Index, unsigned RelOff) const override; + bool needsThunk(RelExpr Expr, uint32_t RelocType, const InputFile *File, + const SymbolBody &S) const override; + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + bool usesOnlyLowPageBits(uint32_t Type) const override; +}; +} // namespace + +template MIPS::MIPS() { + GotPltHeaderEntriesNum = 2; + DefaultMaxPageSize = 65536; + GotEntrySize = sizeof(typename ELFT::uint); + GotPltEntrySize = sizeof(typename ELFT::uint); + PltEntrySize = 16; + PltHeaderSize = 32; + CopyRel = R_MIPS_COPY; + PltRel = R_MIPS_JUMP_SLOT; + NeedsThunks = true; + + if (ELFT::Is64Bits) { + RelativeRel = (R_MIPS_64 << 8) | R_MIPS_REL32; + TlsGotRel = R_MIPS_TLS_TPREL64; + TlsModuleIndexRel = R_MIPS_TLS_DTPMOD64; + TlsOffsetRel = R_MIPS_TLS_DTPREL64; + } else { + RelativeRel = R_MIPS_REL32; + TlsGotRel = R_MIPS_TLS_TPREL32; + TlsModuleIndexRel = R_MIPS_TLS_DTPMOD32; + TlsOffsetRel = R_MIPS_TLS_DTPREL32; + } +} + +template +RelExpr MIPS::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + // See comment in the calculateMipsRelChain. + if (ELFT::Is64Bits || Config->MipsN32Abi) + Type &= 0xff; + switch (Type) { + default: + return R_ABS; + case R_MIPS_JALR: + return R_HINT; + case R_MIPS_GPREL16: + case R_MIPS_GPREL32: + return R_MIPS_GOTREL; + case R_MIPS_26: + return R_PLT; + case R_MIPS_HI16: + case R_MIPS_LO16: + // R_MIPS_HI16/R_MIPS_LO16 relocations against _gp_disp calculate + // offset between start of function and 'gp' value which by default + // equal to the start of .got section. In that case we consider these + // relocations as relative. + if (&S == ElfSym::MipsGpDisp) + return R_MIPS_GOT_GP_PC; + if (&S == ElfSym::MipsLocalGp) + return R_MIPS_GOT_GP; + LLVM_FALLTHROUGH; + case R_MIPS_GOT_OFST: + return R_ABS; + case R_MIPS_PC32: + case R_MIPS_PC16: + case R_MIPS_PC19_S2: + case R_MIPS_PC21_S2: + case R_MIPS_PC26_S2: + case R_MIPS_PCHI16: + case R_MIPS_PCLO16: + return R_PC; + case R_MIPS_GOT16: + if (S.isLocal()) + return R_MIPS_GOT_LOCAL_PAGE; + LLVM_FALLTHROUGH; + case R_MIPS_CALL16: + case R_MIPS_GOT_DISP: + case R_MIPS_TLS_GOTTPREL: + return R_MIPS_GOT_OFF; + case R_MIPS_CALL_HI16: + case R_MIPS_CALL_LO16: + case R_MIPS_GOT_HI16: + case R_MIPS_GOT_LO16: + return R_MIPS_GOT_OFF32; + case R_MIPS_GOT_PAGE: + return R_MIPS_GOT_LOCAL_PAGE; + case R_MIPS_TLS_GD: + return R_MIPS_TLSGD; + case R_MIPS_TLS_LDM: + return R_MIPS_TLSLD; + } +} + +template bool MIPS::isPicRel(uint32_t Type) const { + return Type == R_MIPS_32 || Type == R_MIPS_64; +} + +template uint32_t MIPS::getDynRel(uint32_t Type) const { + return RelativeRel; +} + +template +void MIPS::writeGotPlt(uint8_t *Buf, const SymbolBody &) const { + write32(Buf, InX::Plt->getVA()); +} + +template +static int64_t getPcRelocAddend(const uint8_t *Loc) { + uint32_t Instr = read32(Loc); + uint32_t Mask = 0xffffffff >> (32 - BSIZE); + return SignExtend64((Instr & Mask) << SHIFT); +} + +template +static void applyMipsPcReloc(uint8_t *Loc, uint32_t Type, uint64_t V) { + uint32_t Mask = 0xffffffff >> (32 - BSIZE); + uint32_t Instr = read32(Loc); + if (SHIFT > 0) + checkAlignment<(1 << SHIFT)>(Loc, V, Type); + checkInt(Loc, V, Type); + write32(Loc, (Instr & ~Mask) | ((V >> SHIFT) & Mask)); +} + +template static void writeMipsHi16(uint8_t *Loc, uint64_t V) { + uint32_t Instr = read32(Loc); + uint16_t Res = ((V + 0x8000) >> 16) & 0xffff; + write32(Loc, (Instr & 0xffff0000) | Res); +} + +template static void writeMipsHigher(uint8_t *Loc, uint64_t V) { + uint32_t Instr = read32(Loc); + uint16_t Res = ((V + 0x80008000) >> 32) & 0xffff; + write32(Loc, (Instr & 0xffff0000) | Res); +} + +template static void writeMipsHighest(uint8_t *Loc, uint64_t V) { + uint32_t Instr = read32(Loc); + uint16_t Res = ((V + 0x800080008000) >> 48) & 0xffff; + write32(Loc, (Instr & 0xffff0000) | Res); +} + +template static void writeMipsLo16(uint8_t *Loc, uint64_t V) { + uint32_t Instr = read32(Loc); + write32(Loc, (Instr & 0xffff0000) | (V & 0xffff)); +} + +template static bool isMipsR6() { + const auto &FirstObj = cast>(*Config->FirstElf); + uint32_t Arch = FirstObj.getObj().getHeader()->e_flags & EF_MIPS_ARCH; + return Arch == EF_MIPS_ARCH_32R6 || Arch == EF_MIPS_ARCH_64R6; +} + +template void MIPS::writePltHeader(uint8_t *Buf) const { + const endianness E = ELFT::TargetEndianness; + if (Config->MipsN32Abi) { + write32(Buf, 0x3c0e0000); // lui $14, %hi(&GOTPLT[0]) + write32(Buf + 4, 0x8dd90000); // lw $25, %lo(&GOTPLT[0])($14) + write32(Buf + 8, 0x25ce0000); // addiu $14, $14, %lo(&GOTPLT[0]) + write32(Buf + 12, 0x030ec023); // subu $24, $24, $14 + } else { + write32(Buf, 0x3c1c0000); // lui $28, %hi(&GOTPLT[0]) + write32(Buf + 4, 0x8f990000); // lw $25, %lo(&GOTPLT[0])($28) + write32(Buf + 8, 0x279c0000); // addiu $28, $28, %lo(&GOTPLT[0]) + write32(Buf + 12, 0x031cc023); // subu $24, $24, $28 + } + + write32(Buf + 16, 0x03e07825); // move $15, $31 + write32(Buf + 20, 0x0018c082); // srl $24, $24, 2 + write32(Buf + 24, 0x0320f809); // jalr $25 + write32(Buf + 28, 0x2718fffe); // subu $24, $24, 2 + + uint64_t GotPlt = InX::GotPlt->getVA(); + writeMipsHi16(Buf, GotPlt); + writeMipsLo16(Buf + 4, GotPlt); + writeMipsLo16(Buf + 8, GotPlt); +} + +template +void MIPS::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const { + const endianness E = ELFT::TargetEndianness; + write32(Buf, 0x3c0f0000); // lui $15, %hi(.got.plt entry) + write32(Buf + 4, 0x8df90000); // l[wd] $25, %lo(.got.plt entry)($15) + // jr $25 + write32(Buf + 8, isMipsR6() ? 0x03200009 : 0x03200008); + write32(Buf + 12, 0x25f80000); // addiu $24, $15, %lo(.got.plt entry) + writeMipsHi16(Buf, GotPltEntryAddr); + writeMipsLo16(Buf + 4, GotPltEntryAddr); + writeMipsLo16(Buf + 12, GotPltEntryAddr); +} + +template +bool MIPS::needsThunk(RelExpr Expr, uint32_t Type, const InputFile *File, + const SymbolBody &S) const { + // Any MIPS PIC code function is invoked with its address in register $t9. + // So if we have a branch instruction from non-PIC code to the PIC one + // we cannot make the jump directly and need to create a small stubs + // to save the target function address. + // See page 3-38 ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf + if (Type != R_MIPS_26) + return false; + auto *F = dyn_cast_or_null>(File); + if (!F) + return false; + // If current file has PIC code, LA25 stub is not required. + if (F->getObj().getHeader()->e_flags & EF_MIPS_PIC) + return false; + auto *D = dyn_cast(&S); + // LA25 is required if target file has PIC code + // or target symbol is a PIC symbol. + return D && D->isMipsPIC(); +} + +template +int64_t MIPS::getImplicitAddend(const uint8_t *Buf, uint32_t Type) const { + const endianness E = ELFT::TargetEndianness; + switch (Type) { + default: + return 0; + case R_MIPS_32: + case R_MIPS_GPREL32: + case R_MIPS_TLS_DTPREL32: + case R_MIPS_TLS_TPREL32: + return SignExtend64<32>(read32(Buf)); + case R_MIPS_26: + // FIXME (simon): If the relocation target symbol is not a PLT entry + // we should use another expression for calculation: + // ((A << 2) | (P & 0xf0000000)) >> 2 + return SignExtend64<28>((read32(Buf) & 0x3ffffff) << 2); + case R_MIPS_GPREL16: + case R_MIPS_LO16: + case R_MIPS_PCLO16: + case R_MIPS_TLS_DTPREL_HI16: + case R_MIPS_TLS_DTPREL_LO16: + case R_MIPS_TLS_TPREL_HI16: + case R_MIPS_TLS_TPREL_LO16: + return SignExtend64<16>(read32(Buf)); + case R_MIPS_PC16: + return getPcRelocAddend(Buf); + case R_MIPS_PC19_S2: + return getPcRelocAddend(Buf); + case R_MIPS_PC21_S2: + return getPcRelocAddend(Buf); + case R_MIPS_PC26_S2: + return getPcRelocAddend(Buf); + case R_MIPS_PC32: + return getPcRelocAddend(Buf); + } +} + +static std::pair +calculateMipsRelChain(uint8_t *Loc, uint32_t Type, uint64_t Val) { + // MIPS N64 ABI packs multiple relocations into the single relocation + // record. In general, all up to three relocations can have arbitrary + // types. In fact, Clang and GCC uses only a few combinations. For now, + // we support two of them. That is allow to pass at least all LLVM + // test suite cases. + // / R_MIPS_SUB / R_MIPS_HI16 | R_MIPS_LO16 + // / R_MIPS_64 / R_MIPS_NONE + // The first relocation is a 'real' relocation which is calculated + // using the corresponding symbol's value. The second and the third + // relocations used to modify result of the first one: extend it to + // 64-bit, extract high or low part etc. For details, see part 2.9 Relocation + // at the https://dmz-portal.mips.com/mw/images/8/82/007-4658-001.pdf + uint32_t Type2 = (Type >> 8) & 0xff; + uint32_t Type3 = (Type >> 16) & 0xff; + if (Type2 == R_MIPS_NONE && Type3 == R_MIPS_NONE) + return std::make_pair(Type, Val); + if (Type2 == R_MIPS_64 && Type3 == R_MIPS_NONE) + return std::make_pair(Type2, Val); + if (Type2 == R_MIPS_SUB && (Type3 == R_MIPS_HI16 || Type3 == R_MIPS_LO16)) + return std::make_pair(Type3, -Val); + error(getErrorLocation(Loc) + "unsupported relocations combination " + + Twine(Type)); + return std::make_pair(Type & 0xff, Val); +} + +template +void MIPS::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + const endianness E = ELFT::TargetEndianness; + // Thread pointer and DRP offsets from the start of TLS data area. + // https://www.linux-mips.org/wiki/NPTL + if (Type == R_MIPS_TLS_DTPREL_HI16 || Type == R_MIPS_TLS_DTPREL_LO16 || + Type == R_MIPS_TLS_DTPREL32 || Type == R_MIPS_TLS_DTPREL64) + Val -= 0x8000; + else if (Type == R_MIPS_TLS_TPREL_HI16 || Type == R_MIPS_TLS_TPREL_LO16 || + Type == R_MIPS_TLS_TPREL32 || Type == R_MIPS_TLS_TPREL64) + Val -= 0x7000; + if (ELFT::Is64Bits || Config->MipsN32Abi) + std::tie(Type, Val) = calculateMipsRelChain(Loc, Type, Val); + switch (Type) { + case R_MIPS_32: + case R_MIPS_GPREL32: + case R_MIPS_TLS_DTPREL32: + case R_MIPS_TLS_TPREL32: + write32(Loc, Val); + break; + case R_MIPS_64: + case R_MIPS_TLS_DTPREL64: + case R_MIPS_TLS_TPREL64: + write64(Loc, Val); + break; + case R_MIPS_26: + write32(Loc, (read32(Loc) & ~0x3ffffff) | ((Val >> 2) & 0x3ffffff)); + break; + case R_MIPS_GOT16: + // The R_MIPS_GOT16 relocation's value in "relocatable" linking mode + // is updated addend (not a GOT index). In that case write high 16 bits + // to store a correct addend value. + if (Config->Relocatable) + writeMipsHi16(Loc, Val); + else { + checkInt<16>(Loc, Val, Type); + writeMipsLo16(Loc, Val); + } + break; + case R_MIPS_GOT_DISP: + case R_MIPS_GOT_PAGE: + case R_MIPS_GPREL16: + case R_MIPS_TLS_GD: + case R_MIPS_TLS_LDM: + checkInt<16>(Loc, Val, Type); + LLVM_FALLTHROUGH; + case R_MIPS_CALL16: + case R_MIPS_CALL_LO16: + case R_MIPS_GOT_LO16: + case R_MIPS_GOT_OFST: + case R_MIPS_LO16: + case R_MIPS_PCLO16: + case R_MIPS_TLS_DTPREL_LO16: + case R_MIPS_TLS_GOTTPREL: + case R_MIPS_TLS_TPREL_LO16: + writeMipsLo16(Loc, Val); + break; + case R_MIPS_CALL_HI16: + case R_MIPS_GOT_HI16: + case R_MIPS_HI16: + case R_MIPS_PCHI16: + case R_MIPS_TLS_DTPREL_HI16: + case R_MIPS_TLS_TPREL_HI16: + writeMipsHi16(Loc, Val); + break; + case R_MIPS_HIGHER: + writeMipsHigher(Loc, Val); + break; + case R_MIPS_HIGHEST: + writeMipsHighest(Loc, Val); + break; + case R_MIPS_JALR: + // Ignore this optimization relocation for now + break; + case R_MIPS_PC16: + applyMipsPcReloc(Loc, Type, Val); + break; + case R_MIPS_PC19_S2: + applyMipsPcReloc(Loc, Type, Val); + break; + case R_MIPS_PC21_S2: + applyMipsPcReloc(Loc, Type, Val); + break; + case R_MIPS_PC26_S2: + applyMipsPcReloc(Loc, Type, Val); + break; + case R_MIPS_PC32: + applyMipsPcReloc(Loc, Type, Val); + break; + default: + error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); + } +} + +template +bool MIPS::usesOnlyLowPageBits(uint32_t Type) const { + return Type == R_MIPS_LO16 || Type == R_MIPS_GOT_OFST; +} + +template TargetInfo *elf::createMipsTargetInfo() { + return make>(); +} + +template TargetInfo *elf::createMipsTargetInfo(); +template TargetInfo *elf::createMipsTargetInfo(); +template TargetInfo *elf::createMipsTargetInfo(); +template TargetInfo *elf::createMipsTargetInfo(); Index: lld/ELF/arch/PPC.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/PPC.cpp @@ -0,0 +1,61 @@ +//===- PPC.cpp ------------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "Memory.h" +#include "Symbols.h" +#include "Target.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +class PPC final : public TargetInfo { +public: + PPC() {} + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; +}; + +void PPC::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + switch (Type) { + case R_PPC_ADDR16_HA: + write16be(Loc, (Val + 0x8000) >> 16); + break; + case R_PPC_ADDR16_LO: + write16be(Loc, Val); + break; + case R_PPC_ADDR32: + case R_PPC_REL32: + write32be(Loc, Val); + break; + case R_PPC_REL24: + write32be(Loc, read32be(Loc) | (Val & 0x3FFFFFC)); + break; + default: + error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); + } +} + +RelExpr PPC::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + switch (Type) { + case R_PPC_REL24: + case R_PPC_REL32: + return R_PC; + default: + return R_ABS; + } +} + +TargetInfo *elf::createPPCTargetInfo() { return make(); } Index: lld/ELF/arch/PPC64.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/PPC64.cpp @@ -0,0 +1,215 @@ +//===- PPC64.cpp ----------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "Memory.h" +#include "Symbols.h" +#include "SyntheticSections.h" +#include "Target.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +static uint64_t PPC64TocOffset = 0x8000; + +uint64_t elf::getPPC64TocBase() { + // The TOC consists of sections .got, .toc, .tocbss, .plt in that order. The + // TOC starts where the first of these sections starts. We always create a + // .got when we see a relocation that uses it, so for us the start is always + // the .got. + uint64_t TocVA = InX::Got->getVA(); + + // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000 + // thus permitting a full 64 Kbytes segment. Note that the glibc startup + // code (crt1.o) assumes that you can get from the TOC base to the + // start of the .toc section with only a single (signed) 16-bit relocation. + return TocVA + PPC64TocOffset; +} + +namespace { +class PPC64 final : public TargetInfo { +public: + PPC64(); + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; + void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, + int32_t Index, unsigned RelOff) const override; + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; +}; +} // namespace + +// Relocation masks following the #lo(value), #hi(value), #ha(value), +// #higher(value), #highera(value), #highest(value), and #highesta(value) +// macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi +// document. +static uint16_t applyPPCLo(uint64_t V) { return V; } +static uint16_t applyPPCHi(uint64_t V) { return V >> 16; } +static uint16_t applyPPCHa(uint64_t V) { return (V + 0x8000) >> 16; } +static uint16_t applyPPCHigher(uint64_t V) { return V >> 32; } +static uint16_t applyPPCHighera(uint64_t V) { return (V + 0x8000) >> 32; } +static uint16_t applyPPCHighest(uint64_t V) { return V >> 48; } +static uint16_t applyPPCHighesta(uint64_t V) { return (V + 0x8000) >> 48; } + +PPC64::PPC64() { + PltRel = GotRel = R_PPC64_GLOB_DAT; + RelativeRel = R_PPC64_RELATIVE; + GotEntrySize = 8; + GotPltEntrySize = 8; + PltEntrySize = 32; + PltHeaderSize = 0; + + // We need 64K pages (at least under glibc/Linux, the loader won't + // set different permissions on a finer granularity than that). + DefaultMaxPageSize = 65536; + + // The PPC64 ELF ABI v1 spec, says: + // + // It is normally desirable to put segments with different characteristics + // in separate 256 Mbyte portions of the address space, to give the + // operating system full paging flexibility in the 64-bit address space. + // + // And because the lowest non-zero 256M boundary is 0x10000000, PPC64 linkers + // use 0x10000000 as the starting address. + DefaultImageBase = 0x10000000; +} + +RelExpr PPC64::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + switch (Type) { + default: + return R_ABS; + case R_PPC64_TOC16: + case R_PPC64_TOC16_DS: + case R_PPC64_TOC16_HA: + case R_PPC64_TOC16_HI: + case R_PPC64_TOC16_LO: + case R_PPC64_TOC16_LO_DS: + return R_GOTREL; + case R_PPC64_TOC: + return R_PPC_TOC; + case R_PPC64_REL24: + return R_PPC_PLT_OPD; + } +} + +void PPC64::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, + uint64_t PltEntryAddr, int32_t Index, + unsigned RelOff) const { + uint64_t Off = GotPltEntryAddr - getPPC64TocBase(); + + // FIXME: What we should do, in theory, is get the offset of the function + // descriptor in the .opd section, and use that as the offset from %r2 (the + // TOC-base pointer). Instead, we have the GOT-entry offset, and that will + // be a pointer to the function descriptor in the .opd section. Using + // this scheme is simpler, but requires an extra indirection per PLT dispatch. + + write32be(Buf, 0xf8410028); // std %r2, 40(%r1) + write32be(Buf + 4, 0x3d620000 | applyPPCHa(Off)); // addis %r11, %r2, X@ha + write32be(Buf + 8, 0xe98b0000 | applyPPCLo(Off)); // ld %r12, X@l(%r11) + write32be(Buf + 12, 0xe96c0000); // ld %r11,0(%r12) + write32be(Buf + 16, 0x7d6903a6); // mtctr %r11 + write32be(Buf + 20, 0xe84c0008); // ld %r2,8(%r12) + write32be(Buf + 24, 0xe96c0010); // ld %r11,16(%r12) + write32be(Buf + 28, 0x4e800420); // bctr +} + +static std::pair toAddr16Rel(uint32_t Type, uint64_t Val) { + uint64_t V = Val - PPC64TocOffset; + switch (Type) { + case R_PPC64_TOC16: + return {R_PPC64_ADDR16, V}; + case R_PPC64_TOC16_DS: + return {R_PPC64_ADDR16_DS, V}; + case R_PPC64_TOC16_HA: + return {R_PPC64_ADDR16_HA, V}; + case R_PPC64_TOC16_HI: + return {R_PPC64_ADDR16_HI, V}; + case R_PPC64_TOC16_LO: + return {R_PPC64_ADDR16_LO, V}; + case R_PPC64_TOC16_LO_DS: + return {R_PPC64_ADDR16_LO_DS, V}; + default: + return {Type, Val}; + } +} + +void PPC64::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + // For a TOC-relative relocation, proceed in terms of the corresponding + // ADDR16 relocation type. + std::tie(Type, Val) = toAddr16Rel(Type, Val); + + switch (Type) { + case R_PPC64_ADDR14: { + checkAlignment<4>(Loc, Val, Type); + // Preserve the AA/LK bits in the branch instruction + uint8_t AALK = Loc[3]; + write16be(Loc + 2, (AALK & 3) | (Val & 0xfffc)); + break; + } + case R_PPC64_ADDR16: + checkInt<16>(Loc, Val, Type); + write16be(Loc, Val); + break; + case R_PPC64_ADDR16_DS: + checkInt<16>(Loc, Val, Type); + write16be(Loc, (read16be(Loc) & 3) | (Val & ~3)); + break; + case R_PPC64_ADDR16_HA: + case R_PPC64_REL16_HA: + write16be(Loc, applyPPCHa(Val)); + break; + case R_PPC64_ADDR16_HI: + case R_PPC64_REL16_HI: + write16be(Loc, applyPPCHi(Val)); + break; + case R_PPC64_ADDR16_HIGHER: + write16be(Loc, applyPPCHigher(Val)); + break; + case R_PPC64_ADDR16_HIGHERA: + write16be(Loc, applyPPCHighera(Val)); + break; + case R_PPC64_ADDR16_HIGHEST: + write16be(Loc, applyPPCHighest(Val)); + break; + case R_PPC64_ADDR16_HIGHESTA: + write16be(Loc, applyPPCHighesta(Val)); + break; + case R_PPC64_ADDR16_LO: + write16be(Loc, applyPPCLo(Val)); + break; + case R_PPC64_ADDR16_LO_DS: + case R_PPC64_REL16_LO: + write16be(Loc, (read16be(Loc) & 3) | (applyPPCLo(Val) & ~3)); + break; + case R_PPC64_ADDR32: + case R_PPC64_REL32: + checkInt<32>(Loc, Val, Type); + write32be(Loc, Val); + break; + case R_PPC64_ADDR64: + case R_PPC64_REL64: + case R_PPC64_TOC: + write64be(Loc, Val); + break; + case R_PPC64_REL24: { + uint32_t Mask = 0x03FFFFFC; + checkInt<24>(Loc, Val, Type); + write32be(Loc, (read32be(Loc) & ~Mask) | (Val & Mask)); + break; + } + default: + error(getErrorLocation(Loc) + "unrecognized reloc " + Twine(Type)); + } +} + +TargetInfo *elf::createPPC64TargetInfo() { return make(); } Index: lld/ELF/arch/X86.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/X86.cpp @@ -0,0 +1,362 @@ +//===- X86.cpp ------------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "InputFiles.h" +#include "Memory.h" +#include "Symbols.h" +#include "SyntheticSections.h" +#include "Target.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +namespace { +class X86 final : public TargetInfo { +public: + X86(); + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; + int64_t getImplicitAddend(const uint8_t *Buf, uint32_t Type) const override; + void writeGotPltHeader(uint8_t *Buf) const override; + uint32_t getDynRel(uint32_t Type) const override; + void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; + void writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const override; + void writePltHeader(uint8_t *Buf) const override; + void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, + int32_t Index, unsigned RelOff) const override; + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + + RelExpr adjustRelaxExpr(uint32_t Type, const uint8_t *Data, + RelExpr Expr) const override; + void relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; +}; +} // namespace + +X86::X86() { + CopyRel = R_386_COPY; + GotRel = R_386_GLOB_DAT; + PltRel = R_386_JUMP_SLOT; + IRelativeRel = R_386_IRELATIVE; + RelativeRel = R_386_RELATIVE; + TlsGotRel = R_386_TLS_TPOFF; + TlsModuleIndexRel = R_386_TLS_DTPMOD32; + TlsOffsetRel = R_386_TLS_DTPOFF32; + GotEntrySize = 4; + GotPltEntrySize = 4; + PltEntrySize = 16; + PltHeaderSize = 16; + TlsGdRelaxSkip = 2; + // 0xCC is the "int3" (call debug exception handler) instruction. + TrapInstr = 0xcccccccc; +} + +RelExpr X86::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + switch (Type) { + case R_386_8: + case R_386_16: + case R_386_32: + case R_386_TLS_LDO_32: + return R_ABS; + case R_386_TLS_GD: + return R_TLSGD; + case R_386_TLS_LDM: + return R_TLSLD; + case R_386_PLT32: + return R_PLT_PC; + case R_386_PC8: + case R_386_PC16: + case R_386_PC32: + return R_PC; + case R_386_GOTPC: + return R_GOTONLY_PC_FROM_END; + case R_386_TLS_IE: + return R_GOT; + case R_386_GOT32: + case R_386_GOT32X: + // These relocations can be calculated in two different ways. + // Usual calculation is G + A - GOT what means an offset in GOT table + // (R_GOT_FROM_END). When instruction pointed by relocation has no base + // register, then relocations can be used when PIC code is disabled. In that + // case calculation is G + A, it resolves to an address of entry in GOT + // (R_GOT) and not an offset. + // + // To check that instruction has no base register we scan ModR/M byte. + // See "Table 2-2. 32-Bit Addressing Forms with the ModR/M Byte" + // (http://www.intel.com/content/dam/www/public/us/en/documents/manuals/ + // 64-ia-32-architectures-software-developer-instruction-set-reference-manual-325383.pdf) + if ((Loc[-1] & 0xc7) != 0x5) + return R_GOT_FROM_END; + if (Config->Pic) + error(toString(S.File) + ": relocation " + toString(Type) + " against '" + + S.getName() + + "' without base register can not be used when PIC enabled"); + return R_GOT; + case R_386_TLS_GOTIE: + return R_GOT_FROM_END; + case R_386_GOTOFF: + return R_GOTREL_FROM_END; + case R_386_TLS_LE: + return R_TLS; + case R_386_TLS_LE_32: + return R_NEG_TLS; + case R_386_NONE: + return R_NONE; + default: + error(toString(S.File) + ": unknown relocation type: " + toString(Type)); + return R_HINT; + } +} + +RelExpr X86::adjustRelaxExpr(uint32_t Type, const uint8_t *Data, + RelExpr Expr) const { + switch (Expr) { + default: + return Expr; + case R_RELAX_TLS_GD_TO_IE: + return R_RELAX_TLS_GD_TO_IE_END; + case R_RELAX_TLS_GD_TO_LE: + return R_RELAX_TLS_GD_TO_LE_NEG; + } +} + +void X86::writeGotPltHeader(uint8_t *Buf) const { + write32le(Buf, InX::Dynamic->getVA()); +} + +void X86::writeGotPlt(uint8_t *Buf, const SymbolBody &S) const { + // Entries in .got.plt initially points back to the corresponding + // PLT entries with a fixed offset to skip the first instruction. + write32le(Buf, S.getPltVA() + 6); +} + +void X86::writeIgotPlt(uint8_t *Buf, const SymbolBody &S) const { + // An x86 entry is the address of the ifunc resolver function. + write32le(Buf, S.getVA()); +} + +uint32_t X86::getDynRel(uint32_t Type) const { + if (Type == R_386_TLS_LE) + return R_386_TLS_TPOFF; + if (Type == R_386_TLS_LE_32) + return R_386_TLS_TPOFF32; + return Type; +} + +void X86::writePltHeader(uint8_t *Buf) const { + if (Config->Pic) { + const uint8_t V[] = { + 0xff, 0xb3, 0x04, 0x00, 0x00, 0x00, // pushl GOTPLT+4(%ebx) + 0xff, 0xa3, 0x08, 0x00, 0x00, 0x00, // jmp *GOTPLT+8(%ebx) + 0x90, 0x90, 0x90, 0x90 // nop + }; + memcpy(Buf, V, sizeof(V)); + + uint32_t Ebx = InX::Got->getVA() + InX::Got->getSize(); + uint32_t GotPlt = InX::GotPlt->getVA() - Ebx; + write32le(Buf + 2, GotPlt + 4); + write32le(Buf + 8, GotPlt + 8); + return; + } + + const uint8_t PltData[] = { + 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, // pushl (GOTPLT+4) + 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp *(GOTPLT+8) + 0x90, 0x90, 0x90, 0x90 // nop + }; + memcpy(Buf, PltData, sizeof(PltData)); + uint32_t GotPlt = InX::GotPlt->getVA(); + write32le(Buf + 2, GotPlt + 4); + write32le(Buf + 8, GotPlt + 8); +} + +void X86::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, + 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)); + + if (Config->Pic) { + // jmp *foo@GOT(%ebx) + uint32_t Ebx = InX::Got->getVA() + InX::Got->getSize(); + Buf[1] = 0xa3; + write32le(Buf + 2, GotPltEntryAddr - Ebx); + } else { + // jmp *foo_in_GOT + Buf[1] = 0x25; + write32le(Buf + 2, GotPltEntryAddr); + } + + write32le(Buf + 7, RelOff); + write32le(Buf + 12, -Index * PltEntrySize - PltHeaderSize - 16); +} + +int64_t X86::getImplicitAddend(const uint8_t *Buf, uint32_t Type) const { + switch (Type) { + default: + return 0; + case R_386_8: + case R_386_PC8: + return SignExtend64<8>(*Buf); + case R_386_16: + case R_386_PC16: + return SignExtend64<16>(read16le(Buf)); + case R_386_32: + case R_386_GOT32: + case R_386_GOT32X: + case R_386_GOTOFF: + case R_386_GOTPC: + case R_386_PC32: + case R_386_PLT32: + case R_386_TLS_LDO_32: + case R_386_TLS_LE: + return SignExtend64<32>(read32le(Buf)); + } +} + +void X86::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + // R_386_{PC,}{8,16} are not part of the i386 psABI, but they are + // being used for some 16-bit programs such as boot loaders, so + // we want to support them. + switch (Type) { + case R_386_8: + checkUInt<8>(Loc, Val, Type); + *Loc = Val; + break; + case R_386_PC8: + checkInt<8>(Loc, Val, Type); + *Loc = Val; + break; + case R_386_16: + checkUInt<16>(Loc, Val, Type); + write16le(Loc, Val); + break; + case R_386_PC16: + // R_386_PC16 is normally used with 16 bit code. In that situation + // the PC is 16 bits, just like the addend. This means that it can + // point from any 16 bit address to any other if the possibility + // of wrapping is included. + // The only restriction we have to check then is that the destination + // address fits in 16 bits. That is impossible to do here. The problem is + // that we are passed the final value, which already had the + // current location subtracted from it. + // We just check that Val fits in 17 bits. This misses some cases, but + // should have no false positives. + checkInt<17>(Loc, Val, Type); + write16le(Loc, Val); + break; + default: + checkInt<32>(Loc, Val, Type); + write32le(Loc, Val); + } +} + +void X86::relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + // Convert + // leal x@tlsgd(, %ebx, 1), + // call __tls_get_addr@plt + // to + // movl %gs:0,%eax + // subl $x@ntpoff,%eax + const uint8_t Inst[] = { + 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, // movl %gs:0, %eax + 0x81, 0xe8, 0x00, 0x00, 0x00, 0x00 // subl 0(%ebx), %eax + }; + memcpy(Loc - 3, Inst, sizeof(Inst)); + write32le(Loc + 5, Val); +} + +void X86::relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + // Convert + // leal x@tlsgd(, %ebx, 1), + // call __tls_get_addr@plt + // to + // movl %gs:0, %eax + // addl x@gotntpoff(%ebx), %eax + const uint8_t Inst[] = { + 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, // movl %gs:0, %eax + 0x03, 0x83, 0x00, 0x00, 0x00, 0x00 // addl 0(%ebx), %eax + }; + memcpy(Loc - 3, Inst, sizeof(Inst)); + write32le(Loc + 5, Val); +} + +// In some conditions, relocations can be optimized to avoid using GOT. +// This function does that for Initial Exec to Local Exec case. +void X86::relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + // Ulrich's document section 6.2 says that @gotntpoff can + // be used with MOVL or ADDL instructions. + // @indntpoff is similar to @gotntpoff, but for use in + // position dependent code. + uint8_t Reg = (Loc[-1] >> 3) & 7; + + if (Type == R_386_TLS_IE) { + if (Loc[-1] == 0xa1) { + // "movl foo@indntpoff,%eax" -> "movl $foo,%eax" + // This case is different from the generic case below because + // this is a 5 byte instruction while below is 6 bytes. + Loc[-1] = 0xb8; + } else if (Loc[-2] == 0x8b) { + // "movl foo@indntpoff,%reg" -> "movl $foo,%reg" + Loc[-2] = 0xc7; + Loc[-1] = 0xc0 | Reg; + } else { + // "addl foo@indntpoff,%reg" -> "addl $foo,%reg" + Loc[-2] = 0x81; + Loc[-1] = 0xc0 | Reg; + } + } else { + assert(Type == R_386_TLS_GOTIE); + if (Loc[-2] == 0x8b) { + // "movl foo@gottpoff(%rip),%reg" -> "movl $foo,%reg" + Loc[-2] = 0xc7; + Loc[-1] = 0xc0 | Reg; + } else { + // "addl foo@gotntpoff(%rip),%reg" -> "leal foo(%reg),%reg" + Loc[-2] = 0x8d; + Loc[-1] = 0x80 | (Reg << 3) | Reg; + } + } + write32le(Loc, Val); +} + +void X86::relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const { + if (Type == R_386_TLS_LDO_32) { + write32le(Loc, Val); + return; + } + + // Convert + // leal foo(%reg),%eax + // call ___tls_get_addr + // to + // movl %gs:0,%eax + // nop + // leal 0(%esi,1),%esi + const uint8_t Inst[] = { + 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, // movl %gs:0,%eax + 0x90, // nop + 0x8d, 0x74, 0x26, 0x00 // leal 0(%esi,1),%esi + }; + memcpy(Loc - 2, Inst, sizeof(Inst)); +} + +TargetInfo *elf::createX86TargetInfo() { return make(); } Index: lld/ELF/arch/X86_64.cpp =================================================================== --- /dev/null +++ lld/ELF/arch/X86_64.cpp @@ -0,0 +1,466 @@ +//===- X86_64.cpp ---------------------------------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "Error.h" +#include "InputFiles.h" +#include "Memory.h" +#include "Symbols.h" +#include "SyntheticSections.h" +#include "Target.h" +#include "llvm/Object/ELF.h" +#include "llvm/Support/Endian.h" + +using namespace llvm; +using namespace llvm::object; +using namespace llvm::support::endian; +using namespace llvm::ELF; +using namespace lld; +using namespace lld::elf; + +namespace { +template class X86_64 final : public TargetInfo { +public: + X86_64(); + RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const override; + bool isPicRel(uint32_t Type) const override; + void writeGotPltHeader(uint8_t *Buf) const override; + void writeGotPlt(uint8_t *Buf, const SymbolBody &S) const override; + void writePltHeader(uint8_t *Buf) const override; + void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, + int32_t Index, unsigned RelOff) const override; + void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + + RelExpr adjustRelaxExpr(uint32_t Type, const uint8_t *Data, + RelExpr Expr) const override; + void relaxGot(uint8_t *Loc, uint64_t Val) const override; + void relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + void relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const override; + +private: + void relaxGotNoPic(uint8_t *Loc, uint64_t Val, uint8_t Op, + uint8_t ModRm) const; +}; +} // namespace + +template X86_64::X86_64() { + CopyRel = R_X86_64_COPY; + GotRel = R_X86_64_GLOB_DAT; + PltRel = R_X86_64_JUMP_SLOT; + RelativeRel = R_X86_64_RELATIVE; + IRelativeRel = R_X86_64_IRELATIVE; + TlsGotRel = R_X86_64_TPOFF64; + TlsModuleIndexRel = R_X86_64_DTPMOD64; + TlsOffsetRel = R_X86_64_DTPOFF64; + GotEntrySize = 8; + GotPltEntrySize = 8; + PltEntrySize = 16; + PltHeaderSize = 16; + TlsGdRelaxSkip = 2; + // Align to the large page size (known as a superpage or huge page). + // FreeBSD automatically promotes large, superpage-aligned allocations. + DefaultImageBase = 0x200000; + // 0xCC is the "int3" (call debug exception handler) instruction. + TrapInstr = 0xcccccccc; +} + +template +RelExpr X86_64::getRelExpr(uint32_t Type, const SymbolBody &S, + const uint8_t *Loc) const { + switch (Type) { + case R_X86_64_8: + case R_X86_64_16: + case R_X86_64_32: + case R_X86_64_32S: + case R_X86_64_64: + case R_X86_64_DTPOFF32: + case R_X86_64_DTPOFF64: + return R_ABS; + case R_X86_64_TPOFF32: + return R_TLS; + case R_X86_64_TLSLD: + return R_TLSLD_PC; + case R_X86_64_TLSGD: + return R_TLSGD_PC; + case R_X86_64_SIZE32: + case R_X86_64_SIZE64: + return R_SIZE; + case R_X86_64_PLT32: + return R_PLT_PC; + case R_X86_64_PC32: + case R_X86_64_PC64: + return R_PC; + case R_X86_64_GOT32: + case R_X86_64_GOT64: + return R_GOT_FROM_END; + case R_X86_64_GOTPCREL: + case R_X86_64_GOTPCRELX: + case R_X86_64_REX_GOTPCRELX: + case R_X86_64_GOTTPOFF: + return R_GOT_PC; + case R_X86_64_NONE: + return R_NONE; + default: + error(toString(S.File) + ": unknown relocation type: " + toString(Type)); + return R_HINT; + } +} + +template void X86_64::writeGotPltHeader(uint8_t *Buf) const { + // The first entry holds the value of _DYNAMIC. It is not clear why that is + // required, but it is documented in the psabi and the glibc dynamic linker + // seems to use it (note that this is relevant for linking ld.so, not any + // other program). + write64le(Buf, InX::Dynamic->getVA()); +} + +template +void X86_64::writeGotPlt(uint8_t *Buf, const SymbolBody &S) const { + // See comments in X86TargetInfo::writeGotPlt. + write32le(Buf, S.getPltVA() + 6); +} + +template void X86_64::writePltHeader(uint8_t *Buf) const { + const uint8_t PltData[] = { + 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, // pushq GOTPLT+8(%rip) + 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp *GOTPLT+16(%rip) + 0x0f, 0x1f, 0x40, 0x00 // nop + }; + memcpy(Buf, PltData, sizeof(PltData)); + uint64_t GotPlt = InX::GotPlt->getVA(); + uint64_t Plt = InX::Plt->getVA(); + write32le(Buf + 2, GotPlt - Plt + 2); // GOTPLT+8 + write32le(Buf + 8, GotPlt - Plt + 4); // GOTPLT+16 +} + +template +void X86_64::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, + 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 + 0xe9, 0x00, 0x00, 0x00, 0x00 // jmpq plt[0] + }; + memcpy(Buf, Inst, sizeof(Inst)); + + write32le(Buf + 2, GotPltEntryAddr - PltEntryAddr - 6); + write32le(Buf + 7, Index); + write32le(Buf + 12, -Index * PltEntrySize - PltHeaderSize - 16); +} + +template bool X86_64::isPicRel(uint32_t Type) const { + return Type != R_X86_64_PC32 && Type != R_X86_64_32 && + Type != R_X86_64_TPOFF32; +} + +template +void X86_64::relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, + uint64_t Val) const { + // Convert + // .byte 0x66 + // leaq x@tlsgd(%rip), %rdi + // .word 0x6666 + // rex64 + // call __tls_get_addr@plt + // to + // mov %fs:0x0,%rax + // lea x@tpoff,%rax + const uint8_t Inst[] = { + 0x64, 0x48, 0x8b, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00, // mov %fs:0x0,%rax + 0x48, 0x8d, 0x80, 0x00, 0x00, 0x00, 0x00 // lea x@tpoff,%rax + }; + memcpy(Loc - 4, Inst, sizeof(Inst)); + + // The original code used a pc relative relocation and so we have to + // compensate for the -4 in had in the addend. + write32le(Loc + 8, Val + 4); +} + +template +void X86_64::relaxTlsGdToIe(uint8_t *Loc, uint32_t Type, + uint64_t Val) const { + // Convert + // .byte 0x66 + // leaq x@tlsgd(%rip), %rdi + // .word 0x6666 + // rex64 + // call __tls_get_addr@plt + // to + // mov %fs:0x0,%rax + // addq x@tpoff,%rax + const uint8_t Inst[] = { + 0x64, 0x48, 0x8b, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00, // mov %fs:0x0,%rax + 0x48, 0x03, 0x05, 0x00, 0x00, 0x00, 0x00 // addq x@tpoff,%rax + }; + memcpy(Loc - 4, Inst, sizeof(Inst)); + + // Both code sequences are PC relatives, but since we are moving the constant + // forward by 8 bytes we have to subtract the value by 8. + write32le(Loc + 8, Val - 8); +} + +// In some conditions, R_X86_64_GOTTPOFF relocation can be optimized to +// R_X86_64_TPOFF32 so that it does not use GOT. +template +void X86_64::relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, + uint64_t Val) const { + uint8_t *Inst = Loc - 3; + uint8_t Reg = Loc[-1] >> 3; + uint8_t *RegSlot = Loc - 1; + + // Note that ADD with RSP or R12 is converted to ADD instead of LEA + // because LEA with these registers needs 4 bytes to encode and thus + // wouldn't fit the space. + + if (memcmp(Inst, "\x48\x03\x25", 3) == 0) { + // "addq foo@gottpoff(%rip),%rsp" -> "addq $foo,%rsp" + memcpy(Inst, "\x48\x81\xc4", 3); + } else if (memcmp(Inst, "\x4c\x03\x25", 3) == 0) { + // "addq foo@gottpoff(%rip),%r12" -> "addq $foo,%r12" + memcpy(Inst, "\x49\x81\xc4", 3); + } else if (memcmp(Inst, "\x4c\x03", 2) == 0) { + // "addq foo@gottpoff(%rip),%r[8-15]" -> "leaq foo(%r[8-15]),%r[8-15]" + memcpy(Inst, "\x4d\x8d", 2); + *RegSlot = 0x80 | (Reg << 3) | Reg; + } else if (memcmp(Inst, "\x48\x03", 2) == 0) { + // "addq foo@gottpoff(%rip),%reg -> "leaq foo(%reg),%reg" + memcpy(Inst, "\x48\x8d", 2); + *RegSlot = 0x80 | (Reg << 3) | Reg; + } else if (memcmp(Inst, "\x4c\x8b", 2) == 0) { + // "movq foo@gottpoff(%rip),%r[8-15]" -> "movq $foo,%r[8-15]" + memcpy(Inst, "\x49\xc7", 2); + *RegSlot = 0xc0 | Reg; + } else if (memcmp(Inst, "\x48\x8b", 2) == 0) { + // "movq foo@gottpoff(%rip),%reg" -> "movq $foo,%reg" + memcpy(Inst, "\x48\xc7", 2); + *RegSlot = 0xc0 | Reg; + } else { + error(getErrorLocation(Loc - 3) + + "R_X86_64_GOTTPOFF must be used in MOVQ or ADDQ instructions only"); + } + + // The original code used a PC relative relocation. + // Need to compensate for the -4 it had in the addend. + write32le(Loc, Val + 4); +} + +template +void X86_64::relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, + uint64_t Val) const { + // Convert + // leaq bar@tlsld(%rip), %rdi + // callq __tls_get_addr@PLT + // leaq bar@dtpoff(%rax), %rcx + // to + // .word 0x6666 + // .byte 0x66 + // mov %fs:0,%rax + // leaq bar@tpoff(%rax), %rcx + if (Type == R_X86_64_DTPOFF64) { + write64le(Loc, Val); + return; + } + if (Type == R_X86_64_DTPOFF32) { + write32le(Loc, Val); + return; + } + + const uint8_t Inst[] = { + 0x66, 0x66, // .word 0x6666 + 0x66, // .byte 0x66 + 0x64, 0x48, 0x8b, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00 // mov %fs:0,%rax + }; + memcpy(Loc - 3, Inst, sizeof(Inst)); +} + +template +void X86_64::relocateOne(uint8_t *Loc, uint32_t Type, + uint64_t Val) const { + switch (Type) { + case R_X86_64_8: + checkUInt<8>(Loc, Val, Type); + *Loc = Val; + break; + case R_X86_64_16: + checkUInt<16>(Loc, Val, Type); + write16le(Loc, Val); + break; + case R_X86_64_32: + checkUInt<32>(Loc, Val, Type); + write32le(Loc, Val); + break; + case R_X86_64_32S: + case R_X86_64_TPOFF32: + case R_X86_64_GOT32: + case R_X86_64_GOTPCREL: + case R_X86_64_GOTPCRELX: + case R_X86_64_REX_GOTPCRELX: + case R_X86_64_PC32: + case R_X86_64_GOTTPOFF: + case R_X86_64_PLT32: + case R_X86_64_TLSGD: + case R_X86_64_TLSLD: + case R_X86_64_DTPOFF32: + case R_X86_64_SIZE32: + checkInt<32>(Loc, Val, Type); + write32le(Loc, Val); + break; + case R_X86_64_64: + case R_X86_64_DTPOFF64: + case R_X86_64_GLOB_DAT: + case R_X86_64_PC64: + case R_X86_64_SIZE64: + case R_X86_64_GOT64: + write64le(Loc, Val); + break; + default: + llvm_unreachable("unexpected relocation"); + } +} + +template +RelExpr X86_64::adjustRelaxExpr(uint32_t Type, const uint8_t *Data, + RelExpr RelExpr) const { + if (Type != R_X86_64_GOTPCRELX && Type != R_X86_64_REX_GOTPCRELX) + return RelExpr; + const uint8_t Op = Data[-2]; + const uint8_t ModRm = Data[-1]; + + // FIXME: When PIC is disabled and foo is defined locally in the + // lower 32 bit address space, memory operand in mov can be converted into + // immediate operand. Otherwise, mov must be changed to lea. We support only + // latter relaxation at this moment. + if (Op == 0x8b) + return R_RELAX_GOT_PC; + + // Relax call and jmp. + if (Op == 0xff && (ModRm == 0x15 || ModRm == 0x25)) + return R_RELAX_GOT_PC; + + // Relaxation of test, adc, add, and, cmp, or, sbb, sub, xor. + // If PIC then no relaxation is available. + // We also don't relax test/binop instructions without REX byte, + // they are 32bit operations and not common to have. + assert(Type == R_X86_64_REX_GOTPCRELX); + return Config->Pic ? RelExpr : R_RELAX_GOT_PC_NOPIC; +} + +// A subset of relaxations can only be applied for no-PIC. This method +// handles such relaxations. Instructions encoding information was taken from: +// "Intel 64 and IA-32 Architectures Software Developer's Manual V2" +// (http://www.intel.com/content/dam/www/public/us/en/documents/manuals/ +// 64-ia-32-architectures-software-developer-instruction-set-reference-manual-325383.pdf) +template +void X86_64::relaxGotNoPic(uint8_t *Loc, uint64_t Val, uint8_t Op, + uint8_t ModRm) const { + const uint8_t Rex = Loc[-3]; + // Convert "test %reg, foo@GOTPCREL(%rip)" to "test $foo, %reg". + if (Op == 0x85) { + // See "TEST-Logical Compare" (4-428 Vol. 2B), + // TEST r/m64, r64 uses "full" ModR / M byte (no opcode extension). + + // ModR/M byte has form XX YYY ZZZ, where + // YYY is MODRM.reg(register 2), ZZZ is MODRM.rm(register 1). + // XX has different meanings: + // 00: The operand's memory address is in reg1. + // 01: The operand's memory address is reg1 + a byte-sized displacement. + // 10: The operand's memory address is reg1 + a word-sized displacement. + // 11: The operand is reg1 itself. + // If an instruction requires only one operand, the unused reg2 field + // holds extra opcode bits rather than a register code + // 0xC0 == 11 000 000 binary. + // 0x38 == 00 111 000 binary. + // We transfer reg2 to reg1 here as operand. + // See "2.1.3 ModR/M and SIB Bytes" (Vol. 2A 2-3). + Loc[-1] = 0xc0 | (ModRm & 0x38) >> 3; // ModR/M byte. + + // Change opcode from TEST r/m64, r64 to TEST r/m64, imm32 + // See "TEST-Logical Compare" (4-428 Vol. 2B). + Loc[-2] = 0xf7; + + // Move R bit to the B bit in REX byte. + // REX byte is encoded as 0100WRXB, where + // 0100 is 4bit fixed pattern. + // REX.W When 1, a 64-bit operand size is used. Otherwise, when 0, the + // default operand size is used (which is 32-bit for most but not all + // instructions). + // REX.R This 1-bit value is an extension to the MODRM.reg field. + // REX.X This 1-bit value is an extension to the SIB.index field. + // REX.B This 1-bit value is an extension to the MODRM.rm field or the + // SIB.base field. + // See "2.2.1.2 More on REX Prefix Fields " (2-8 Vol. 2A). + Loc[-3] = (Rex & ~0x4) | (Rex & 0x4) >> 2; + write32le(Loc, Val); + return; + } + + // If we are here then we need to relax the adc, add, and, cmp, or, sbb, sub + // or xor operations. + + // Convert "binop foo@GOTPCREL(%rip), %reg" to "binop $foo, %reg". + // Logic is close to one for test instruction above, but we also + // write opcode extension here, see below for details. + Loc[-1] = 0xc0 | (ModRm & 0x38) >> 3 | (Op & 0x3c); // ModR/M byte. + + // Primary opcode is 0x81, opcode extension is one of: + // 000b = ADD, 001b is OR, 010b is ADC, 011b is SBB, + // 100b is AND, 101b is SUB, 110b is XOR, 111b is CMP. + // This value was wrote to MODRM.reg in a line above. + // See "3.2 INSTRUCTIONS (A-M)" (Vol. 2A 3-15), + // "INSTRUCTION SET REFERENCE, N-Z" (Vol. 2B 4-1) for + // descriptions about each operation. + Loc[-2] = 0x81; + Loc[-3] = (Rex & ~0x4) | (Rex & 0x4) >> 2; + write32le(Loc, Val); +} + +template +void X86_64::relaxGot(uint8_t *Loc, uint64_t Val) const { + const uint8_t Op = Loc[-2]; + const uint8_t ModRm = Loc[-1]; + + // Convert "mov foo@GOTPCREL(%rip),%reg" to "lea foo(%rip),%reg". + if (Op == 0x8b) { + Loc[-2] = 0x8d; + write32le(Loc, Val); + return; + } + + if (Op != 0xff) { + // We are relaxing a rip relative to an absolute, so compensate + // for the old -4 addend. + assert(!Config->Pic); + relaxGotNoPic(Loc, Val + 4, Op, ModRm); + return; + } + + // Convert call/jmp instructions. + if (ModRm == 0x15) { + // ABI says we can convert "call *foo@GOTPCREL(%rip)" to "nop; call foo". + // Instead we convert to "addr32 call foo" where addr32 is an instruction + // prefix. That makes result expression to be a single instruction. + Loc[-2] = 0x67; // addr32 prefix + Loc[-1] = 0xe8; // call + write32le(Loc, Val); + return; + } + + // Convert "jmp *foo@GOTPCREL(%rip)" to "jmp foo; nop". + // jmp doesn't return, so it is fine to use nop here, it is just a stub. + assert(ModRm == 0x25); + Loc[-2] = 0xe9; // jmp + Loc[3] = 0x90; // nop + write32le(Loc - 1, Val + 1); +} + +TargetInfo *elf::createX32TargetInfo() { return make>(); } +TargetInfo *elf::createX86_64TargetInfo() { return make>(); }