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Diffstat (limited to 'contrib/llvm/lib/Target/X86/X86TargetObjectFile.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/X86/X86TargetObjectFile.cpp | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/X86/X86TargetObjectFile.cpp b/contrib/llvm/lib/Target/X86/X86TargetObjectFile.cpp new file mode 100644 index 000000000000..7f70829cb6c6 --- /dev/null +++ b/contrib/llvm/lib/Target/X86/X86TargetObjectFile.cpp @@ -0,0 +1,184 @@ +//===-- X86TargetObjectFile.cpp - X86 Object Info -------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "X86TargetObjectFile.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/IR/Mangler.h" +#include "llvm/IR/Operator.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCSectionCOFF.h" +#include "llvm/MC/MCSectionELF.h" +#include "llvm/MC/MCValue.h" +#include "llvm/Support/COFF.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Target/TargetLowering.h" + +using namespace llvm; +using namespace dwarf; + +const MCExpr *X86_64MachoTargetObjectFile::getTTypeGlobalReference( + const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM, + MachineModuleInfo *MMI, MCStreamer &Streamer) const { + + // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which + // is an indirect pc-relative reference. + if ((Encoding & DW_EH_PE_indirect) && (Encoding & DW_EH_PE_pcrel)) { + const MCSymbol *Sym = TM.getSymbol(GV); + const MCExpr *Res = + MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext()); + const MCExpr *Four = MCConstantExpr::create(4, getContext()); + return MCBinaryExpr::createAdd(Res, Four, getContext()); + } + + return TargetLoweringObjectFileMachO::getTTypeGlobalReference( + GV, Encoding, TM, MMI, Streamer); +} + +MCSymbol *X86_64MachoTargetObjectFile::getCFIPersonalitySymbol( + const GlobalValue *GV, const TargetMachine &TM, + MachineModuleInfo *MMI) const { + return TM.getSymbol(GV); +} + +const MCExpr *X86_64MachoTargetObjectFile::getIndirectSymViaGOTPCRel( + const MCSymbol *Sym, const MCValue &MV, int64_t Offset, + MachineModuleInfo *MMI, MCStreamer &Streamer) const { + // On Darwin/X86-64, we need to use foo@GOTPCREL+4 to access the got entry + // from a data section. In case there's an additional offset, then use + // foo@GOTPCREL+4+<offset>. + unsigned FinalOff = Offset+MV.getConstant()+4; + const MCExpr *Res = + MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext()); + const MCExpr *Off = MCConstantExpr::create(FinalOff, getContext()); + return MCBinaryExpr::createAdd(Res, Off, getContext()); +} + +const MCExpr *X86ELFTargetObjectFile::getDebugThreadLocalSymbol( + const MCSymbol *Sym) const { + return MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext()); +} + +void +X86FreeBSDTargetObjectFile::Initialize(MCContext &Ctx, + const TargetMachine &TM) { + TargetLoweringObjectFileELF::Initialize(Ctx, TM); + InitializeELF(TM.Options.UseInitArray); +} + +void +X86FuchsiaTargetObjectFile::Initialize(MCContext &Ctx, + const TargetMachine &TM) { + TargetLoweringObjectFileELF::Initialize(Ctx, TM); + InitializeELF(TM.Options.UseInitArray); +} + +void +X86LinuxNaClTargetObjectFile::Initialize(MCContext &Ctx, + const TargetMachine &TM) { + TargetLoweringObjectFileELF::Initialize(Ctx, TM); + InitializeELF(TM.Options.UseInitArray); +} + +const MCExpr *X86WindowsTargetObjectFile::lowerRelativeReference( + const GlobalValue *LHS, const GlobalValue *RHS, + const TargetMachine &TM) const { + // Our symbols should exist in address space zero, cowardly no-op if + // otherwise. + if (LHS->getType()->getPointerAddressSpace() != 0 || + RHS->getType()->getPointerAddressSpace() != 0) + return nullptr; + + // Both ptrtoint instructions must wrap global objects: + // - Only global variables are eligible for image relative relocations. + // - The subtrahend refers to the special symbol __ImageBase, a GlobalVariable. + // We expect __ImageBase to be a global variable without a section, externally + // defined. + // + // It should look something like this: @__ImageBase = external constant i8 + if (!isa<GlobalObject>(LHS) || !isa<GlobalVariable>(RHS) || + LHS->isThreadLocal() || RHS->isThreadLocal() || + RHS->getName() != "__ImageBase" || !RHS->hasExternalLinkage() || + cast<GlobalVariable>(RHS)->hasInitializer() || RHS->hasSection()) + return nullptr; + + return MCSymbolRefExpr::create(TM.getSymbol(LHS), + MCSymbolRefExpr::VK_COFF_IMGREL32, + getContext()); +} + +static std::string APIntToHexString(const APInt &AI) { + unsigned Width = (AI.getBitWidth() / 8) * 2; + std::string HexString = utohexstr(AI.getLimitedValue(), /*LowerCase=*/true); + unsigned Size = HexString.size(); + assert(Width >= Size && "hex string is too large!"); + HexString.insert(HexString.begin(), Width - Size, '0'); + + return HexString; +} + +static std::string scalarConstantToHexString(const Constant *C) { + Type *Ty = C->getType(); + if (isa<UndefValue>(C)) { + return APIntToHexString(APInt::getNullValue(Ty->getPrimitiveSizeInBits())); + } else if (const auto *CFP = dyn_cast<ConstantFP>(C)) { + return APIntToHexString(CFP->getValueAPF().bitcastToAPInt()); + } else if (const auto *CI = dyn_cast<ConstantInt>(C)) { + return APIntToHexString(CI->getValue()); + } else { + unsigned NumElements; + if (isa<VectorType>(Ty)) + NumElements = Ty->getVectorNumElements(); + else + NumElements = Ty->getArrayNumElements(); + std::string HexString; + for (int I = NumElements - 1, E = -1; I != E; --I) + HexString += scalarConstantToHexString(C->getAggregateElement(I)); + return HexString; + } +} + +MCSection *X86WindowsTargetObjectFile::getSectionForConstant( + const DataLayout &DL, SectionKind Kind, const Constant *C, + unsigned &Align) const { + if (Kind.isMergeableConst() && C) { + const unsigned Characteristics = COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | + COFF::IMAGE_SCN_MEM_READ | + COFF::IMAGE_SCN_LNK_COMDAT; + std::string COMDATSymName; + if (Kind.isMergeableConst4()) { + if (Align <= 4) { + COMDATSymName = "__real@" + scalarConstantToHexString(C); + Align = 4; + } + } else if (Kind.isMergeableConst8()) { + if (Align <= 8) { + COMDATSymName = "__real@" + scalarConstantToHexString(C); + Align = 8; + } + } else if (Kind.isMergeableConst16()) { + if (Align <= 16) { + COMDATSymName = "__xmm@" + scalarConstantToHexString(C); + Align = 16; + } + } else if (Kind.isMergeableConst32()) { + if (Align <= 32) { + COMDATSymName = "__ymm@" + scalarConstantToHexString(C); + Align = 32; + } + } + + if (!COMDATSymName.empty()) + return getContext().getCOFFSection(".rdata", Characteristics, Kind, + COMDATSymName, + COFF::IMAGE_COMDAT_SELECT_ANY); + } + + return TargetLoweringObjectFile::getSectionForConstant(DL, Kind, C, Align); +} |