X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FMachObjectWriter.cpp;h=ce222b75cf4de4b7067645c4aca2c0e3101fbcc4;hb=8b9300b972745a6d89b482cbcd4206c01359f7df;hp=02a5575606dfde9451c4915ab3c44fe1dbda08fe;hpb=7070387f08f7dc797b554ed8013cba9f8b74121a;p=oota-llvm.git diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp index 02a5575606d..ce222b75cf4 100644 --- a/lib/MC/MachObjectWriter.cpp +++ b/lib/MC/MachObjectWriter.cpp @@ -7,10 +7,12 @@ // //===----------------------------------------------------------------------===// -#include "llvm/MC/MachObjectWriter.h" +#include "llvm/MC/MCMachObjectWriter.h" +#include "llvm/ADT/OwningPtr.h" #include "llvm/ADT/StringMap.h" #include "llvm/ADT/Twine.h" #include "llvm/MC/MCAssembler.h" +#include "llvm/MC/MCAsmBackend.h" #include "llvm/MC/MCAsmLayout.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCObjectWriter.h" @@ -18,50 +20,15 @@ #include "llvm/MC/MCSymbol.h" #include "llvm/MC/MCMachOSymbolFlags.h" #include "llvm/MC/MCValue.h" +#include "llvm/Object/MachOFormat.h" #include "llvm/Support/ErrorHandling.h" -#include "llvm/Support/MachO.h" -#include "llvm/Target/TargetAsmBackend.h" - -// FIXME: Gross. -#include "../Target/X86/X86FixupKinds.h" #include using namespace llvm; +using namespace llvm::object; -static unsigned getFixupKindLog2Size(unsigned Kind) { - switch (Kind) { - default: llvm_unreachable("invalid fixup kind!"); - case X86::reloc_pcrel_1byte: - case FK_Data_1: return 0; - case X86::reloc_pcrel_2byte: - case FK_Data_2: return 1; - case X86::reloc_pcrel_4byte: - case X86::reloc_riprel_4byte: - case X86::reloc_riprel_4byte_movq_load: - case FK_Data_4: return 2; - case FK_Data_8: return 3; - } -} - -static bool isFixupKindPCRel(unsigned Kind) { - switch (Kind) { - default: - return false; - case X86::reloc_pcrel_1byte: - case X86::reloc_pcrel_2byte: - case X86::reloc_pcrel_4byte: - case X86::reloc_riprel_4byte: - case X86::reloc_riprel_4byte_movq_load: - return true; - } -} - -static bool isFixupKindRIPRel(unsigned Kind) { - return Kind == X86::reloc_riprel_4byte || - Kind == X86::reloc_riprel_4byte_movq_load; -} - -static bool doesSymbolRequireExternRelocation(MCSymbolData *SD) { +bool MachObjectWriter:: +doesSymbolRequireExternRelocation(const MCSymbolData *SD) { // Undefined symbols are always extern. if (SD->Symbol->isUndefined()) return true; @@ -75,1274 +42,764 @@ static bool doesSymbolRequireExternRelocation(MCSymbolData *SD) { return false; } -static bool isScatteredFixupFullyResolved(const MCAssembler &Asm, - const MCValue Target, - const MCSymbolData *BaseSymbol) { - // The effective fixup address is - // addr(atom(A)) + offset(A) - // - addr(atom(B)) - offset(B) - // - addr(BaseSymbol) + - // and the offsets are not relocatable, so the fixup is fully resolved when - // addr(atom(A)) - addr(atom(B)) - addr(BaseSymbol) == 0. - // - // Note that "false" is almost always conservatively correct (it means we emit - // a relocation which is unnecessary), except when it would force us to emit a - // relocation which the target cannot encode. +bool MachObjectWriter:: +MachSymbolData::operator<(const MachSymbolData &RHS) const { + return SymbolData->getSymbol().getName() < + RHS.SymbolData->getSymbol().getName(); +} - const MCSymbolData *A_Base = 0, *B_Base = 0; - if (const MCSymbolRefExpr *A = Target.getSymA()) { - // Modified symbol references cannot be resolved. - if (A->getKind() != MCSymbolRefExpr::VK_None) - return false; +bool MachObjectWriter::isFixupKindPCRel(const MCAssembler &Asm, unsigned Kind) { + const MCFixupKindInfo &FKI = Asm.getBackend().getFixupKindInfo( + (MCFixupKind) Kind); - A_Base = Asm.getAtom(&Asm.getSymbolData(A->getSymbol())); - if (!A_Base) - return false; - } + return FKI.Flags & MCFixupKindInfo::FKF_IsPCRel; +} - if (const MCSymbolRefExpr *B = Target.getSymB()) { - // Modified symbol references cannot be resolved. - if (B->getKind() != MCSymbolRefExpr::VK_None) - return false; +uint64_t MachObjectWriter::getFragmentAddress(const MCFragment *Fragment, + const MCAsmLayout &Layout) const { + return getSectionAddress(Fragment->getParent()) + + Layout.getFragmentOffset(Fragment); +} - B_Base = Asm.getAtom(&Asm.getSymbolData(B->getSymbol())); - if (!B_Base) - return false; +uint64_t MachObjectWriter::getSymbolAddress(const MCSymbolData* SD, + const MCAsmLayout &Layout) const { + const MCSymbol &S = SD->getSymbol(); + + // If this is a variable, then recursively evaluate now. + if (S.isVariable()) { + MCValue Target; + if (!S.getVariableValue()->EvaluateAsRelocatable(Target, Layout)) + report_fatal_error("unable to evaluate offset for variable '" + + S.getName() + "'"); + + // Verify that any used symbols are defined. + if (Target.getSymA() && Target.getSymA()->getSymbol().isUndefined()) + report_fatal_error("unable to evaluate offset to undefined symbol '" + + Target.getSymA()->getSymbol().getName() + "'"); + if (Target.getSymB() && Target.getSymB()->getSymbol().isUndefined()) + report_fatal_error("unable to evaluate offset to undefined symbol '" + + Target.getSymB()->getSymbol().getName() + "'"); + + uint64_t Address = Target.getConstant(); + if (Target.getSymA()) + Address += getSymbolAddress(&Layout.getAssembler().getSymbolData( + Target.getSymA()->getSymbol()), Layout); + if (Target.getSymB()) + Address += getSymbolAddress(&Layout.getAssembler().getSymbolData( + Target.getSymB()->getSymbol()), Layout); + return Address; } - // If there is no base, A and B have to be the same atom for this fixup to be - // fully resolved. - if (!BaseSymbol) - return A_Base == B_Base; - - // Otherwise, B must be missing and A must be the base. - return !B_Base && BaseSymbol == A_Base; + return getSectionAddress(SD->getFragment()->getParent()) + + Layout.getSymbolOffset(SD); } -static bool isScatteredFixupFullyResolvedSimple(const MCAssembler &Asm, - const MCValue Target, - const MCSection *BaseSection) { - // The effective fixup address is - // addr(atom(A)) + offset(A) - // - addr(atom(B)) - offset(B) - // - addr() + - // and the offsets are not relocatable, so the fixup is fully resolved when - // addr(atom(A)) - addr(atom(B)) - addr()) == 0. - // - // The simple (Darwin, except on x86_64) way of dealing with this was to - // assume that any reference to a temporary symbol *must* be a temporary - // symbol in the same atom, unless the sections differ. Therefore, any PCrel - // relocation to a temporary symbol (in the same section) is fully - // resolved. This also works in conjunction with absolutized .set, which - // requires the compiler to use .set to absolutize the differences between - // symbols which the compiler knows to be assembly time constants, so we don't - // need to worry about considering symbol differences fully resolved. - - // Non-relative fixups are only resolved if constant. - if (!BaseSection) - return Target.isAbsolute(); - - // Otherwise, relative fixups are only resolved if not a difference and the - // target is a temporary in the same section. - if (Target.isAbsolute() || Target.getSymB()) - return false; - - const MCSymbol *A = &Target.getSymA()->getSymbol(); - if (!A->isTemporary() || !A->isInSection() || - &A->getSection() != BaseSection) - return false; - - return true; +uint64_t MachObjectWriter::getPaddingSize(const MCSectionData *SD, + const MCAsmLayout &Layout) const { + uint64_t EndAddr = getSectionAddress(SD) + Layout.getSectionAddressSize(SD); + unsigned Next = SD->getLayoutOrder() + 1; + if (Next >= Layout.getSectionOrder().size()) + return 0; + + const MCSectionData &NextSD = *Layout.getSectionOrder()[Next]; + if (NextSD.getSection().isVirtualSection()) + return 0; + return OffsetToAlignment(EndAddr, NextSD.getAlignment()); } -namespace { - -class MachObjectWriterImpl { - // See . - enum { - Header_Magic32 = 0xFEEDFACE, - Header_Magic64 = 0xFEEDFACF - }; - - enum { - Header32Size = 28, - Header64Size = 32, - SegmentLoadCommand32Size = 56, - SegmentLoadCommand64Size = 72, - Section32Size = 68, - Section64Size = 80, - SymtabLoadCommandSize = 24, - DysymtabLoadCommandSize = 80, - Nlist32Size = 12, - Nlist64Size = 16, - RelocationInfoSize = 8 - }; - - enum HeaderFileType { - HFT_Object = 0x1 - }; - - enum HeaderFlags { - HF_SubsectionsViaSymbols = 0x2000 - }; - - enum LoadCommandType { - LCT_Segment = 0x1, - LCT_Symtab = 0x2, - LCT_Dysymtab = 0xb, - LCT_Segment64 = 0x19 - }; - - // See . - enum SymbolTypeType { - STT_Undefined = 0x00, - STT_Absolute = 0x02, - STT_Section = 0x0e - }; - - enum SymbolTypeFlags { - // If any of these bits are set, then the entry is a stab entry number (see - // . Otherwise the other masks apply. - STF_StabsEntryMask = 0xe0, - - STF_TypeMask = 0x0e, - STF_External = 0x01, - STF_PrivateExtern = 0x10 - }; - - /// IndirectSymbolFlags - Flags for encoding special values in the indirect - /// symbol entry. - enum IndirectSymbolFlags { - ISF_Local = 0x80000000, - ISF_Absolute = 0x40000000 - }; - - /// RelocationFlags - Special flags for addresses. - enum RelocationFlags { - RF_Scattered = 0x80000000 - }; - - enum RelocationInfoType { - RIT_Vanilla = 0, - RIT_Pair = 1, - RIT_Difference = 2, - RIT_PreboundLazyPointer = 3, - RIT_LocalDifference = 4, - RIT_TLV = 5 - }; - - /// X86_64 uses its own relocation types. - enum RelocationInfoTypeX86_64 { - RIT_X86_64_Unsigned = 0, - RIT_X86_64_Signed = 1, - RIT_X86_64_Branch = 2, - RIT_X86_64_GOTLoad = 3, - RIT_X86_64_GOT = 4, - RIT_X86_64_Subtractor = 5, - RIT_X86_64_Signed1 = 6, - RIT_X86_64_Signed2 = 7, - RIT_X86_64_Signed4 = 8, - RIT_X86_64_TLV = 9 - }; - - /// MachSymbolData - Helper struct for containing some precomputed information - /// on symbols. - struct MachSymbolData { - MCSymbolData *SymbolData; - uint64_t StringIndex; - uint8_t SectionIndex; - - // Support lexicographic sorting. - bool operator<(const MachSymbolData &RHS) const { - return SymbolData->getSymbol().getName() < - RHS.SymbolData->getSymbol().getName(); - } - }; +void MachObjectWriter::WriteHeader(unsigned NumLoadCommands, + unsigned LoadCommandsSize, + bool SubsectionsViaSymbols) { + uint32_t Flags = 0; - /// @name Relocation Data - /// @{ + if (SubsectionsViaSymbols) + Flags |= macho::HF_SubsectionsViaSymbols; - struct MachRelocationEntry { - uint32_t Word0; - uint32_t Word1; - }; + // struct mach_header (28 bytes) or + // struct mach_header_64 (32 bytes) - llvm::DenseMap > Relocations; - llvm::DenseMap IndirectSymBase; + uint64_t Start = OS.tell(); + (void) Start; - /// @} - /// @name Symbol Table Data - /// @{ + Write32(is64Bit() ? macho::HM_Object64 : macho::HM_Object32); - SmallString<256> StringTable; - std::vector LocalSymbolData; - std::vector ExternalSymbolData; - std::vector UndefinedSymbolData; + Write32(TargetObjectWriter->getCPUType()); + Write32(TargetObjectWriter->getCPUSubtype()); - /// @} + Write32(macho::HFT_Object); + Write32(NumLoadCommands); + Write32(LoadCommandsSize); + Write32(Flags); + if (is64Bit()) + Write32(0); // reserved - MachObjectWriter *Writer; + assert(OS.tell() - Start == + (is64Bit() ? macho::Header64Size : macho::Header32Size)); +} - raw_ostream &OS; +/// WriteSegmentLoadCommand - Write a segment load command. +/// +/// \arg NumSections - The number of sections in this segment. +/// \arg SectionDataSize - The total size of the sections. +void MachObjectWriter::WriteSegmentLoadCommand(unsigned NumSections, + uint64_t VMSize, + uint64_t SectionDataStartOffset, + uint64_t SectionDataSize) { + // struct segment_command (56 bytes) or + // struct segment_command_64 (72 bytes) + + uint64_t Start = OS.tell(); + (void) Start; + + unsigned SegmentLoadCommandSize = + is64Bit() ? macho::SegmentLoadCommand64Size: + macho::SegmentLoadCommand32Size; + Write32(is64Bit() ? macho::LCT_Segment64 : macho::LCT_Segment); + Write32(SegmentLoadCommandSize + + NumSections * (is64Bit() ? macho::Section64Size : + macho::Section32Size)); + + WriteBytes("", 16); + if (is64Bit()) { + Write64(0); // vmaddr + Write64(VMSize); // vmsize + Write64(SectionDataStartOffset); // file offset + Write64(SectionDataSize); // file size + } else { + Write32(0); // vmaddr + Write32(VMSize); // vmsize + Write32(SectionDataStartOffset); // file offset + Write32(SectionDataSize); // file size + } + Write32(0x7); // maxprot + Write32(0x7); // initprot + Write32(NumSections); + Write32(0); // flags - unsigned Is64Bit : 1; + assert(OS.tell() - Start == SegmentLoadCommandSize); +} -public: - MachObjectWriterImpl(MachObjectWriter *_Writer, bool _Is64Bit) - : Writer(_Writer), OS(Writer->getStream()), Is64Bit(_Is64Bit) { +void MachObjectWriter::WriteSection(const MCAssembler &Asm, + const MCAsmLayout &Layout, + const MCSectionData &SD, + uint64_t FileOffset, + uint64_t RelocationsStart, + unsigned NumRelocations) { + uint64_t SectionSize = Layout.getSectionAddressSize(&SD); + + // The offset is unused for virtual sections. + if (SD.getSection().isVirtualSection()) { + assert(Layout.getSectionFileSize(&SD) == 0 && "Invalid file size!"); + FileOffset = 0; } - void Write8(uint8_t Value) { Writer->Write8(Value); } - void Write16(uint16_t Value) { Writer->Write16(Value); } - void Write32(uint32_t Value) { Writer->Write32(Value); } - void Write64(uint64_t Value) { Writer->Write64(Value); } - void WriteZeros(unsigned N) { Writer->WriteZeros(N); } - void WriteBytes(StringRef Str, unsigned ZeroFillSize = 0) { - Writer->WriteBytes(Str, ZeroFillSize); + // struct section (68 bytes) or + // struct section_64 (80 bytes) + + uint64_t Start = OS.tell(); + (void) Start; + + const MCSectionMachO &Section = cast(SD.getSection()); + WriteBytes(Section.getSectionName(), 16); + WriteBytes(Section.getSegmentName(), 16); + if (is64Bit()) { + Write64(getSectionAddress(&SD)); // address + Write64(SectionSize); // size + } else { + Write32(getSectionAddress(&SD)); // address + Write32(SectionSize); // size } + Write32(FileOffset); + + unsigned Flags = Section.getTypeAndAttributes(); + if (SD.hasInstructions()) + Flags |= MCSectionMachO::S_ATTR_SOME_INSTRUCTIONS; + + assert(isPowerOf2_32(SD.getAlignment()) && "Invalid alignment!"); + Write32(Log2_32(SD.getAlignment())); + Write32(NumRelocations ? RelocationsStart : 0); + Write32(NumRelocations); + Write32(Flags); + Write32(IndirectSymBase.lookup(&SD)); // reserved1 + Write32(Section.getStubSize()); // reserved2 + if (is64Bit()) + Write32(0); // reserved3 + + assert(OS.tell() - Start == (is64Bit() ? macho::Section64Size : + macho::Section32Size)); +} - void WriteHeader(unsigned NumLoadCommands, unsigned LoadCommandsSize, - bool SubsectionsViaSymbols) { - uint32_t Flags = 0; - - if (SubsectionsViaSymbols) - Flags |= HF_SubsectionsViaSymbols; +void MachObjectWriter::WriteSymtabLoadCommand(uint32_t SymbolOffset, + uint32_t NumSymbols, + uint32_t StringTableOffset, + uint32_t StringTableSize) { + // struct symtab_command (24 bytes) - // struct mach_header (28 bytes) or - // struct mach_header_64 (32 bytes) + uint64_t Start = OS.tell(); + (void) Start; - uint64_t Start = OS.tell(); - (void) Start; + Write32(macho::LCT_Symtab); + Write32(macho::SymtabLoadCommandSize); + Write32(SymbolOffset); + Write32(NumSymbols); + Write32(StringTableOffset); + Write32(StringTableSize); - Write32(Is64Bit ? Header_Magic64 : Header_Magic32); + assert(OS.tell() - Start == macho::SymtabLoadCommandSize); +} - // FIXME: Support cputype. - Write32(Is64Bit ? MachO::CPUTypeX86_64 : MachO::CPUTypeI386); - // FIXME: Support cpusubtype. - Write32(MachO::CPUSubType_I386_ALL); - Write32(HFT_Object); - Write32(NumLoadCommands); // Object files have a single load command, the - // segment. - Write32(LoadCommandsSize); - Write32(Flags); - if (Is64Bit) - Write32(0); // reserved +void MachObjectWriter::WriteDysymtabLoadCommand(uint32_t FirstLocalSymbol, + uint32_t NumLocalSymbols, + uint32_t FirstExternalSymbol, + uint32_t NumExternalSymbols, + uint32_t FirstUndefinedSymbol, + uint32_t NumUndefinedSymbols, + uint32_t IndirectSymbolOffset, + uint32_t NumIndirectSymbols) { + // struct dysymtab_command (80 bytes) + + uint64_t Start = OS.tell(); + (void) Start; + + Write32(macho::LCT_Dysymtab); + Write32(macho::DysymtabLoadCommandSize); + Write32(FirstLocalSymbol); + Write32(NumLocalSymbols); + Write32(FirstExternalSymbol); + Write32(NumExternalSymbols); + Write32(FirstUndefinedSymbol); + Write32(NumUndefinedSymbols); + Write32(0); // tocoff + Write32(0); // ntoc + Write32(0); // modtaboff + Write32(0); // nmodtab + Write32(0); // extrefsymoff + Write32(0); // nextrefsyms + Write32(IndirectSymbolOffset); + Write32(NumIndirectSymbols); + Write32(0); // extreloff + Write32(0); // nextrel + Write32(0); // locreloff + Write32(0); // nlocrel + + assert(OS.tell() - Start == macho::DysymtabLoadCommandSize); +} - assert(OS.tell() - Start == Is64Bit ? Header64Size : Header32Size); - } +void MachObjectWriter::WriteNlist(MachSymbolData &MSD, + const MCAsmLayout &Layout) { + MCSymbolData &Data = *MSD.SymbolData; + const MCSymbol &Symbol = Data.getSymbol(); + uint8_t Type = 0; + uint16_t Flags = Data.getFlags(); + uint64_t Address = 0; - /// WriteSegmentLoadCommand - Write a segment load command. - /// - /// \arg NumSections - The number of sections in this segment. - /// \arg SectionDataSize - The total size of the sections. - void WriteSegmentLoadCommand(unsigned NumSections, - uint64_t VMSize, - uint64_t SectionDataStartOffset, - uint64_t SectionDataSize) { - // struct segment_command (56 bytes) or - // struct segment_command_64 (72 bytes) - - uint64_t Start = OS.tell(); - (void) Start; - - unsigned SegmentLoadCommandSize = Is64Bit ? SegmentLoadCommand64Size : - SegmentLoadCommand32Size; - Write32(Is64Bit ? LCT_Segment64 : LCT_Segment); - Write32(SegmentLoadCommandSize + - NumSections * (Is64Bit ? Section64Size : Section32Size)); - - WriteBytes("", 16); - if (Is64Bit) { - Write64(0); // vmaddr - Write64(VMSize); // vmsize - Write64(SectionDataStartOffset); // file offset - Write64(SectionDataSize); // file size + // Set the N_TYPE bits. See . + // + // FIXME: Are the prebound or indirect fields possible here? + if (Symbol.isUndefined()) + Type = macho::STT_Undefined; + else if (Symbol.isAbsolute()) + Type = macho::STT_Absolute; + else + Type = macho::STT_Section; + + // FIXME: Set STAB bits. + + if (Data.isPrivateExtern()) + Type |= macho::STF_PrivateExtern; + + // Set external bit. + if (Data.isExternal() || Symbol.isUndefined()) + Type |= macho::STF_External; + + // Compute the symbol address. + if (Symbol.isDefined()) { + if (Symbol.isAbsolute()) { + Address = cast(Symbol.getVariableValue())->getValue(); } else { - Write32(0); // vmaddr - Write32(VMSize); // vmsize - Write32(SectionDataStartOffset); // file offset - Write32(SectionDataSize); // file size + Address = getSymbolAddress(&Data, Layout); + } + } else if (Data.isCommon()) { + // Common symbols are encoded with the size in the address + // field, and their alignment in the flags. + Address = Data.getCommonSize(); + + // Common alignment is packed into the 'desc' bits. + if (unsigned Align = Data.getCommonAlignment()) { + unsigned Log2Size = Log2_32(Align); + assert((1U << Log2Size) == Align && "Invalid 'common' alignment!"); + if (Log2Size > 15) + report_fatal_error("invalid 'common' alignment '" + + Twine(Align) + "'"); + // FIXME: Keep this mask with the SymbolFlags enumeration. + Flags = (Flags & 0xF0FF) | (Log2Size << 8); } - Write32(0x7); // maxprot - Write32(0x7); // initprot - Write32(NumSections); - Write32(0); // flags - - assert(OS.tell() - Start == SegmentLoadCommandSize); } - void WriteSection(const MCAssembler &Asm, const MCAsmLayout &Layout, - const MCSectionData &SD, uint64_t FileOffset, - uint64_t RelocationsStart, unsigned NumRelocations) { - uint64_t SectionSize = Layout.getSectionSize(&SD); + // struct nlist (12 bytes) - // The offset is unused for virtual sections. - if (Asm.getBackend().isVirtualSection(SD.getSection())) { - assert(Layout.getSectionFileSize(&SD) == 0 && "Invalid file size!"); - FileOffset = 0; - } - - // struct section (68 bytes) or - // struct section_64 (80 bytes) + Write32(MSD.StringIndex); + Write8(Type); + Write8(MSD.SectionIndex); - uint64_t Start = OS.tell(); - (void) Start; + // The Mach-O streamer uses the lowest 16-bits of the flags for the 'desc' + // value. + Write16(Flags); + if (is64Bit()) + Write64(Address); + else + Write32(Address); +} - const MCSectionMachO &Section = cast(SD.getSection()); - WriteBytes(Section.getSectionName(), 16); - WriteBytes(Section.getSegmentName(), 16); - if (Is64Bit) { - Write64(Layout.getSectionAddress(&SD)); // address - Write64(SectionSize); // size - } else { - Write32(Layout.getSectionAddress(&SD)); // address - Write32(SectionSize); // size - } - Write32(FileOffset); - - unsigned Flags = Section.getTypeAndAttributes(); - if (SD.hasInstructions()) - Flags |= MCSectionMachO::S_ATTR_SOME_INSTRUCTIONS; - - assert(isPowerOf2_32(SD.getAlignment()) && "Invalid alignment!"); - Write32(Log2_32(SD.getAlignment())); - Write32(NumRelocations ? RelocationsStart : 0); - Write32(NumRelocations); - Write32(Flags); - Write32(IndirectSymBase.lookup(&SD)); // reserved1 - Write32(Section.getStubSize()); // reserved2 - if (Is64Bit) - Write32(0); // reserved3 - - assert(OS.tell() - Start == Is64Bit ? Section64Size : Section32Size); - } +void MachObjectWriter::RecordRelocation(const MCAssembler &Asm, + const MCAsmLayout &Layout, + const MCFragment *Fragment, + const MCFixup &Fixup, + MCValue Target, + uint64_t &FixedValue) { + TargetObjectWriter->RecordRelocation(this, Asm, Layout, Fragment, Fixup, + Target, FixedValue); +} - void WriteSymtabLoadCommand(uint32_t SymbolOffset, uint32_t NumSymbols, - uint32_t StringTableOffset, - uint32_t StringTableSize) { - // struct symtab_command (24 bytes) +void MachObjectWriter::BindIndirectSymbols(MCAssembler &Asm) { + // This is the point where 'as' creates actual symbols for indirect symbols + // (in the following two passes). It would be easier for us to do this sooner + // when we see the attribute, but that makes getting the order in the symbol + // table much more complicated than it is worth. + // + // FIXME: Revisit this when the dust settles. - uint64_t Start = OS.tell(); - (void) Start; + // Bind non lazy symbol pointers first. + unsigned IndirectIndex = 0; + for (MCAssembler::indirect_symbol_iterator it = Asm.indirect_symbol_begin(), + ie = Asm.indirect_symbol_end(); it != ie; ++it, ++IndirectIndex) { + const MCSectionMachO &Section = + cast(it->SectionData->getSection()); - Write32(LCT_Symtab); - Write32(SymtabLoadCommandSize); - Write32(SymbolOffset); - Write32(NumSymbols); - Write32(StringTableOffset); - Write32(StringTableSize); + if (Section.getType() != MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS) + continue; - assert(OS.tell() - Start == SymtabLoadCommandSize); - } + // Initialize the section indirect symbol base, if necessary. + if (!IndirectSymBase.count(it->SectionData)) + IndirectSymBase[it->SectionData] = IndirectIndex; - void WriteDysymtabLoadCommand(uint32_t FirstLocalSymbol, - uint32_t NumLocalSymbols, - uint32_t FirstExternalSymbol, - uint32_t NumExternalSymbols, - uint32_t FirstUndefinedSymbol, - uint32_t NumUndefinedSymbols, - uint32_t IndirectSymbolOffset, - uint32_t NumIndirectSymbols) { - // struct dysymtab_command (80 bytes) - - uint64_t Start = OS.tell(); - (void) Start; - - Write32(LCT_Dysymtab); - Write32(DysymtabLoadCommandSize); - Write32(FirstLocalSymbol); - Write32(NumLocalSymbols); - Write32(FirstExternalSymbol); - Write32(NumExternalSymbols); - Write32(FirstUndefinedSymbol); - Write32(NumUndefinedSymbols); - Write32(0); // tocoff - Write32(0); // ntoc - Write32(0); // modtaboff - Write32(0); // nmodtab - Write32(0); // extrefsymoff - Write32(0); // nextrefsyms - Write32(IndirectSymbolOffset); - Write32(NumIndirectSymbols); - Write32(0); // extreloff - Write32(0); // nextrel - Write32(0); // locreloff - Write32(0); // nlocrel - - assert(OS.tell() - Start == DysymtabLoadCommandSize); + Asm.getOrCreateSymbolData(*it->Symbol); } - void WriteNlist(MachSymbolData &MSD, const MCAsmLayout &Layout) { - MCSymbolData &Data = *MSD.SymbolData; - const MCSymbol &Symbol = Data.getSymbol(); - uint8_t Type = 0; - uint16_t Flags = Data.getFlags(); - uint32_t Address = 0; - - // Set the N_TYPE bits. See . - // - // FIXME: Are the prebound or indirect fields possible here? - if (Symbol.isUndefined()) - Type = STT_Undefined; - else if (Symbol.isAbsolute()) - Type = STT_Absolute; - else - Type = STT_Section; - - // FIXME: Set STAB bits. - - if (Data.isPrivateExtern()) - Type |= STF_PrivateExtern; - - // Set external bit. - if (Data.isExternal() || Symbol.isUndefined()) - Type |= STF_External; - - // Compute the symbol address. - if (Symbol.isDefined()) { - if (Symbol.isAbsolute()) { - Address = cast(Symbol.getVariableValue())->getValue(); - } else { - Address = Layout.getSymbolAddress(&Data); - } - } else if (Data.isCommon()) { - // Common symbols are encoded with the size in the address - // field, and their alignment in the flags. - Address = Data.getCommonSize(); - - // Common alignment is packed into the 'desc' bits. - if (unsigned Align = Data.getCommonAlignment()) { - unsigned Log2Size = Log2_32(Align); - assert((1U << Log2Size) == Align && "Invalid 'common' alignment!"); - if (Log2Size > 15) - report_fatal_error("invalid 'common' alignment '" + - Twine(Align) + "'"); - // FIXME: Keep this mask with the SymbolFlags enumeration. - Flags = (Flags & 0xF0FF) | (Log2Size << 8); - } - } + // Then lazy symbol pointers and symbol stubs. + IndirectIndex = 0; + for (MCAssembler::indirect_symbol_iterator it = Asm.indirect_symbol_begin(), + ie = Asm.indirect_symbol_end(); it != ie; ++it, ++IndirectIndex) { + const MCSectionMachO &Section = + cast(it->SectionData->getSection()); - // struct nlist (12 bytes) + if (Section.getType() != MCSectionMachO::S_LAZY_SYMBOL_POINTERS && + Section.getType() != MCSectionMachO::S_SYMBOL_STUBS) + continue; - Write32(MSD.StringIndex); - Write8(Type); - Write8(MSD.SectionIndex); + // Initialize the section indirect symbol base, if necessary. + if (!IndirectSymBase.count(it->SectionData)) + IndirectSymBase[it->SectionData] = IndirectIndex; - // The Mach-O streamer uses the lowest 16-bits of the flags for the 'desc' - // value. - Write16(Flags); - if (Is64Bit) - Write64(Address); - else - Write32(Address); + // Set the symbol type to undefined lazy, but only on construction. + // + // FIXME: Do not hardcode. + bool Created; + MCSymbolData &Entry = Asm.getOrCreateSymbolData(*it->Symbol, &Created); + if (Created) + Entry.setFlags(Entry.getFlags() | 0x0001); } +} - // FIXME: We really need to improve the relocation validation. Basically, we - // want to implement a separate computation which evaluates the relocation - // entry as the linker would, and verifies that the resultant fixup value is - // exactly what the encoder wanted. This will catch several classes of - // problems: - // - // - Relocation entry bugs, the two algorithms are unlikely to have the same - // exact bug. +/// ComputeSymbolTable - Compute the symbol table data +/// +/// \param StringTable [out] - The string table data. +/// \param StringIndexMap [out] - Map from symbol names to offsets in the +/// string table. +void MachObjectWriter:: +ComputeSymbolTable(MCAssembler &Asm, SmallString<256> &StringTable, + std::vector &LocalSymbolData, + std::vector &ExternalSymbolData, + std::vector &UndefinedSymbolData) { + // Build section lookup table. + DenseMap SectionIndexMap; + unsigned Index = 1; + for (MCAssembler::iterator it = Asm.begin(), + ie = Asm.end(); it != ie; ++it, ++Index) + SectionIndexMap[&it->getSection()] = Index; + assert(Index <= 256 && "Too many sections!"); + + // Index 0 is always the empty string. + StringMap StringIndexMap; + StringTable += '\x00'; + + // Build the symbol arrays and the string table, but only for non-local + // symbols. // - // - Relaxation issues, where we forget to relax something. - // - // - Input errors, where something cannot be correctly encoded. 'as' allows - // these through in many cases. - - void RecordX86_64Relocation(const MCAssembler &Asm, const MCAsmLayout &Layout, - const MCFragment *Fragment, - const MCFixup &Fixup, MCValue Target, - uint64_t &FixedValue) { - unsigned IsPCRel = isFixupKindPCRel(Fixup.getKind()); - unsigned IsRIPRel = isFixupKindRIPRel(Fixup.getKind()); - unsigned Log2Size = getFixupKindLog2Size(Fixup.getKind()); - - // See . - uint32_t FixupOffset = - Layout.getFragmentOffset(Fragment) + Fixup.getOffset(); - uint32_t FixupAddress = - Layout.getFragmentAddress(Fragment) + Fixup.getOffset(); - int64_t Value = 0; - unsigned Index = 0; - unsigned IsExtern = 0; - unsigned Type = 0; - - Value = Target.getConstant(); - - if (IsPCRel) { - // Compensate for the relocation offset, Darwin x86_64 relocations only - // have the addend and appear to have attempted to define it to be the - // actual expression addend without the PCrel bias. However, instructions - // with data following the relocation are not accomodated for (see comment - // below regarding SIGNED{1,2,4}), so it isn't exactly that either. - Value += 1LL << Log2Size; + // The particular order that we collect the symbols and create the string + // table, then sort the symbols is chosen to match 'as'. Even though it + // doesn't matter for correctness, this is important for letting us diff .o + // files. + for (MCAssembler::symbol_iterator it = Asm.symbol_begin(), + ie = Asm.symbol_end(); it != ie; ++it) { + const MCSymbol &Symbol = it->getSymbol(); + + // Ignore non-linker visible symbols. + if (!Asm.isSymbolLinkerVisible(it->getSymbol())) + continue; + + if (!it->isExternal() && !Symbol.isUndefined()) + continue; + + uint64_t &Entry = StringIndexMap[Symbol.getName()]; + if (!Entry) { + Entry = StringTable.size(); + StringTable += Symbol.getName(); + StringTable += '\x00'; } - if (Target.isAbsolute()) { // constant - // SymbolNum of 0 indicates the absolute section. - Type = RIT_X86_64_Unsigned; - Index = 0; - - // FIXME: I believe this is broken, I don't think the linker can - // understand it. I think it would require a local relocation, but I'm not - // sure if that would work either. The official way to get an absolute - // PCrel relocation is to use an absolute symbol (which we don't support - // yet). - if (IsPCRel) { - IsExtern = 1; - Type = RIT_X86_64_Branch; - } - } else if (Target.getSymB()) { // A - B + constant - const MCSymbol *A = &Target.getSymA()->getSymbol(); - MCSymbolData &A_SD = Asm.getSymbolData(*A); - const MCSymbolData *A_Base = Asm.getAtom(&A_SD); - - const MCSymbol *B = &Target.getSymB()->getSymbol(); - MCSymbolData &B_SD = Asm.getSymbolData(*B); - const MCSymbolData *B_Base = Asm.getAtom(&B_SD); - - // Neither symbol can be modified. - if (Target.getSymA()->getKind() != MCSymbolRefExpr::VK_None || - Target.getSymB()->getKind() != MCSymbolRefExpr::VK_None) - report_fatal_error("unsupported relocation of modified symbol"); - - // We don't support PCrel relocations of differences. Darwin 'as' doesn't - // implement most of these correctly. - if (IsPCRel) - report_fatal_error("unsupported pc-relative relocation of difference"); - - // We don't currently support any situation where one or both of the - // symbols would require a local relocation. This is almost certainly - // unused and may not be possible to encode correctly. - if (!A_Base || !B_Base) - report_fatal_error("unsupported local relocations in difference"); - - // Darwin 'as' doesn't emit correct relocations for this (it ends up with - // a single SIGNED relocation); reject it for now. - if (A_Base == B_Base) - report_fatal_error("unsupported relocation with identical base"); - - Value += Layout.getSymbolAddress(&A_SD) - Layout.getSymbolAddress(A_Base); - Value -= Layout.getSymbolAddress(&B_SD) - Layout.getSymbolAddress(B_Base); - - Index = A_Base->getIndex(); - IsExtern = 1; - Type = RIT_X86_64_Unsigned; - - MachRelocationEntry MRE; - MRE.Word0 = FixupOffset; - MRE.Word1 = ((Index << 0) | - (IsPCRel << 24) | - (Log2Size << 25) | - (IsExtern << 27) | - (Type << 28)); - Relocations[Fragment->getParent()].push_back(MRE); - - Index = B_Base->getIndex(); - IsExtern = 1; - Type = RIT_X86_64_Subtractor; - } else { - const MCSymbol *Symbol = &Target.getSymA()->getSymbol(); - MCSymbolData &SD = Asm.getSymbolData(*Symbol); - const MCSymbolData *Base = Asm.getAtom(&SD); - - // Relocations inside debug sections always use local relocations when - // possible. This seems to be done because the debugger doesn't fully - // understand x86_64 relocation entries, and expects to find values that - // have already been fixed up. - if (Symbol->isInSection()) { - const MCSectionMachO &Section = static_cast( - Fragment->getParent()->getSection()); - if (Section.hasAttribute(MCSectionMachO::S_ATTR_DEBUG)) - Base = 0; - } + MachSymbolData MSD; + MSD.SymbolData = it; + MSD.StringIndex = Entry; - // x86_64 almost always uses external relocations, except when there is no - // symbol to use as a base address (a local symbol with no preceeding - // non-local symbol). - if (Base) { - Index = Base->getIndex(); - IsExtern = 1; - - // Add the local offset, if needed. - if (Base != &SD) - Value += Layout.getSymbolAddress(&SD) - Layout.getSymbolAddress(Base); - } else if (Symbol->isInSection()) { - // The index is the section ordinal (1-based). - Index = SD.getFragment()->getParent()->getOrdinal() + 1; - IsExtern = 0; - Value += Layout.getSymbolAddress(&SD); - - if (IsPCRel) - Value -= FixupAddress + (1 << Log2Size); - } else { - report_fatal_error("unsupported relocation of undefined symbol '" + - Symbol->getName() + "'"); - } - - MCSymbolRefExpr::VariantKind Modifier = Target.getSymA()->getKind(); - if (IsPCRel) { - if (IsRIPRel) { - if (Modifier == MCSymbolRefExpr::VK_GOTPCREL) { - // x86_64 distinguishes movq foo@GOTPCREL so that the linker can - // rewrite the movq to an leaq at link time if the symbol ends up in - // the same linkage unit. - if (unsigned(Fixup.getKind()) == X86::reloc_riprel_4byte_movq_load) - Type = RIT_X86_64_GOTLoad; - else - Type = RIT_X86_64_GOT; - } else if (Modifier == MCSymbolRefExpr::VK_TLVP) { - Type = RIT_X86_64_TLV; - } else if (Modifier != MCSymbolRefExpr::VK_None) { - report_fatal_error("unsupported symbol modifier in relocation"); - } else { - Type = RIT_X86_64_Signed; - - // The Darwin x86_64 relocation format has a problem where it cannot - // encode an address (L + ) which is outside the atom - // containing L. Generally, this shouldn't occur but it does - // happen when we have a RIPrel instruction with data following the - // relocation entry (e.g., movb $012, L0(%rip)). Even with the PCrel - // adjustment Darwin x86_64 uses, the offset is still negative and - // the linker has no way to recognize this. - // - // To work around this, Darwin uses several special relocation types - // to indicate the offsets. However, the specification or - // implementation of these seems to also be incomplete; they should - // adjust the addend as well based on the actual encoded instruction - // (the additional bias), but instead appear to just look at the - // final offset. - switch (-(Target.getConstant() + (1LL << Log2Size))) { - case 1: Type = RIT_X86_64_Signed1; break; - case 2: Type = RIT_X86_64_Signed2; break; - case 4: Type = RIT_X86_64_Signed4; break; - } - } - } else { - if (Modifier != MCSymbolRefExpr::VK_None) - report_fatal_error("unsupported symbol modifier in branch " - "relocation"); - - Type = RIT_X86_64_Branch; - } - } else { - if (Modifier == MCSymbolRefExpr::VK_GOT) { - Type = RIT_X86_64_GOT; - } else if (Modifier == MCSymbolRefExpr::VK_GOTPCREL) { - // GOTPCREL is allowed as a modifier on non-PCrel instructions, in - // which case all we do is set the PCrel bit in the relocation entry; - // this is used with exception handling, for example. The source is - // required to include any necessary offset directly. - Type = RIT_X86_64_GOT; - IsPCRel = 1; - } else if (Modifier == MCSymbolRefExpr::VK_TLVP) { - report_fatal_error("TLVP symbol modifier should have been rip-rel"); - } else if (Modifier != MCSymbolRefExpr::VK_None) - report_fatal_error("unsupported symbol modifier in relocation"); - else - Type = RIT_X86_64_Unsigned; - } + if (Symbol.isUndefined()) { + MSD.SectionIndex = 0; + UndefinedSymbolData.push_back(MSD); + } else if (Symbol.isAbsolute()) { + MSD.SectionIndex = 0; + ExternalSymbolData.push_back(MSD); + } else { + MSD.SectionIndex = SectionIndexMap.lookup(&Symbol.getSection()); + assert(MSD.SectionIndex && "Invalid section index!"); + ExternalSymbolData.push_back(MSD); } - - // x86_64 always writes custom values into the fixups. - FixedValue = Value; - - // struct relocation_info (8 bytes) - MachRelocationEntry MRE; - MRE.Word0 = FixupOffset; - MRE.Word1 = ((Index << 0) | - (IsPCRel << 24) | - (Log2Size << 25) | - (IsExtern << 27) | - (Type << 28)); - Relocations[Fragment->getParent()].push_back(MRE); } - void RecordScatteredRelocation(const MCAssembler &Asm, - const MCAsmLayout &Layout, - const MCFragment *Fragment, - const MCFixup &Fixup, MCValue Target, - uint64_t &FixedValue) { - uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset(); - unsigned IsPCRel = isFixupKindPCRel(Fixup.getKind()); - unsigned Log2Size = getFixupKindLog2Size(Fixup.getKind()); - unsigned Type = RIT_Vanilla; - - // See . - const MCSymbol *A = &Target.getSymA()->getSymbol(); - MCSymbolData *A_SD = &Asm.getSymbolData(*A); - - if (!A_SD->getFragment()) - report_fatal_error("symbol '" + A->getName() + - "' can not be undefined in a subtraction expression"); - - uint32_t Value = Layout.getSymbolAddress(A_SD); - uint32_t Value2 = 0; - - if (const MCSymbolRefExpr *B = Target.getSymB()) { - MCSymbolData *B_SD = &Asm.getSymbolData(B->getSymbol()); - - if (!B_SD->getFragment()) - report_fatal_error("symbol '" + B->getSymbol().getName() + - "' can not be undefined in a subtraction expression"); - - // Select the appropriate difference relocation type. - // - // Note that there is no longer any semantic difference between these two - // relocation types from the linkers point of view, this is done solely - // for pedantic compatibility with 'as'. - Type = A_SD->isExternal() ? RIT_Difference : RIT_LocalDifference; - Value2 = Layout.getSymbolAddress(B_SD); - } - - // Relocations are written out in reverse order, so the PAIR comes first. - if (Type == RIT_Difference || Type == RIT_LocalDifference) { - MachRelocationEntry MRE; - MRE.Word0 = ((0 << 0) | - (RIT_Pair << 24) | - (Log2Size << 28) | - (IsPCRel << 30) | - RF_Scattered); - MRE.Word1 = Value2; - Relocations[Fragment->getParent()].push_back(MRE); - } + // Now add the data for local symbols. + for (MCAssembler::symbol_iterator it = Asm.symbol_begin(), + ie = Asm.symbol_end(); it != ie; ++it) { + const MCSymbol &Symbol = it->getSymbol(); - MachRelocationEntry MRE; - MRE.Word0 = ((FixupOffset << 0) | - (Type << 24) | - (Log2Size << 28) | - (IsPCRel << 30) | - RF_Scattered); - MRE.Word1 = Value; - Relocations[Fragment->getParent()].push_back(MRE); - } - - void RecordTLVPRelocation(const MCAssembler &Asm, - const MCAsmLayout &Layout, - const MCFragment *Fragment, - const MCFixup &Fixup, MCValue Target, - uint64_t &FixedValue) { - assert(Target.getSymA()->getKind() == MCSymbolRefExpr::VK_TLVP && - !Is64Bit && - "Should only be called with a 32-bit TLVP relocation!"); - - unsigned Log2Size = getFixupKindLog2Size(Fixup.getKind()); - uint32_t Value = Layout.getFragmentOffset(Fragment)+Fixup.getOffset(); - unsigned IsPCRel = 0; - - // Get the symbol data. - MCSymbolData *SD_A = &Asm.getSymbolData(Target.getSymA()->getSymbol()); - unsigned Index = SD_A->getIndex(); - - // We're only going to have a second symbol in pic mode and it'll be a - // subtraction from the picbase. For 32-bit pic the addend is the difference - // between the picbase and the next address. For 32-bit static the addend - // is zero. - if (Target.getSymB()) { - // If this is a subtraction then we're pcrel. - uint32_t FixupAddress = - Layout.getFragmentAddress(Fragment) + Fixup.getOffset(); - MCSymbolData *SD_B = &Asm.getSymbolData(Target.getSymB()->getSymbol()); - IsPCRel = 1; - FixedValue = (FixupAddress - Layout.getSymbolAddress(SD_B) + - Target.getConstant()); - FixedValue += 1ULL << Log2Size; - } else { - FixedValue = 0; - } - - // struct relocation_info (8 bytes) - MachRelocationEntry MRE; - MRE.Word0 = Value; - MRE.Word1 = ((Index << 0) | - (IsPCRel << 24) | - (Log2Size << 25) | - (1 << 27) | // Extern - (RIT_TLV << 28)); // Type - Relocations[Fragment->getParent()].push_back(MRE); - } - - void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout, - const MCFragment *Fragment, const MCFixup &Fixup, - MCValue Target, uint64_t &FixedValue) { - if (Is64Bit) { - RecordX86_64Relocation(Asm, Layout, Fragment, Fixup, Target, FixedValue); - return; - } + // Ignore non-linker visible symbols. + if (!Asm.isSymbolLinkerVisible(it->getSymbol())) + continue; - unsigned IsPCRel = isFixupKindPCRel(Fixup.getKind()); - unsigned Log2Size = getFixupKindLog2Size(Fixup.getKind()); + if (it->isExternal() || Symbol.isUndefined()) + continue; - // If this is a 32-bit TLVP reloc it's handled a bit differently. - if (Target.getSymA() && - Target.getSymA()->getKind() == MCSymbolRefExpr::VK_TLVP) { - RecordTLVPRelocation(Asm, Layout, Fragment, Fixup, Target, FixedValue); - return; + uint64_t &Entry = StringIndexMap[Symbol.getName()]; + if (!Entry) { + Entry = StringTable.size(); + StringTable += Symbol.getName(); + StringTable += '\x00'; } - - // If this is a difference or a defined symbol plus an offset, then we need - // a scattered relocation entry. - // Differences always require scattered relocations. - if (Target.getSymB()) - return RecordScatteredRelocation(Asm, Layout, Fragment, Fixup, - Target, FixedValue); - // Get the symbol data, if any. - MCSymbolData *SD = 0; - if (Target.getSymA()) - SD = &Asm.getSymbolData(Target.getSymA()->getSymbol()); - - // If this is an internal relocation with an offset, it also needs a - // scattered relocation entry. - uint32_t Offset = Target.getConstant(); - if (IsPCRel) - Offset += 1 << Log2Size; - if (Offset && SD && !doesSymbolRequireExternRelocation(SD)) - return RecordScatteredRelocation(Asm, Layout, Fragment, Fixup, - Target, FixedValue); + MachSymbolData MSD; + MSD.SymbolData = it; + MSD.StringIndex = Entry; - // See . - uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset(); - unsigned Index = 0; - unsigned IsExtern = 0; - unsigned Type = 0; - - if (Target.isAbsolute()) { // constant - // SymbolNum of 0 indicates the absolute section. - // - // FIXME: Currently, these are never generated (see code below). I cannot - // find a case where they are actually emitted. - Type = RIT_Vanilla; + if (Symbol.isAbsolute()) { + MSD.SectionIndex = 0; + LocalSymbolData.push_back(MSD); } else { - // Check whether we need an external or internal relocation. - if (doesSymbolRequireExternRelocation(SD)) { - IsExtern = 1; - Index = SD->getIndex(); - // For external relocations, make sure to offset the fixup value to - // compensate for the addend of the symbol address, if it was - // undefined. This occurs with weak definitions, for example. - if (!SD->Symbol->isUndefined()) - FixedValue -= Layout.getSymbolAddress(SD); - } else { - // The index is the section ordinal (1-based). - Index = SD->getFragment()->getParent()->getOrdinal() + 1; - } - - Type = RIT_Vanilla; + MSD.SectionIndex = SectionIndexMap.lookup(&Symbol.getSection()); + assert(MSD.SectionIndex && "Invalid section index!"); + LocalSymbolData.push_back(MSD); } - - // struct relocation_info (8 bytes) - MachRelocationEntry MRE; - MRE.Word0 = FixupOffset; - MRE.Word1 = ((Index << 0) | - (IsPCRel << 24) | - (Log2Size << 25) | - (IsExtern << 27) | - (Type << 28)); - Relocations[Fragment->getParent()].push_back(MRE); } - void BindIndirectSymbols(MCAssembler &Asm) { - // This is the point where 'as' creates actual symbols for indirect symbols - // (in the following two passes). It would be easier for us to do this - // sooner when we see the attribute, but that makes getting the order in the - // symbol table much more complicated than it is worth. - // - // FIXME: Revisit this when the dust settles. + // External and undefined symbols are required to be in lexicographic order. + std::sort(ExternalSymbolData.begin(), ExternalSymbolData.end()); + std::sort(UndefinedSymbolData.begin(), UndefinedSymbolData.end()); + + // Set the symbol indices. + Index = 0; + for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i) + LocalSymbolData[i].SymbolData->setIndex(Index++); + for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i) + ExternalSymbolData[i].SymbolData->setIndex(Index++); + for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i) + UndefinedSymbolData[i].SymbolData->setIndex(Index++); + + // The string table is padded to a multiple of 4. + while (StringTable.size() % 4) + StringTable += '\x00'; +} - // Bind non lazy symbol pointers first. - unsigned IndirectIndex = 0; - for (MCAssembler::indirect_symbol_iterator it = Asm.indirect_symbol_begin(), - ie = Asm.indirect_symbol_end(); it != ie; ++it, ++IndirectIndex) { - const MCSectionMachO &Section = - cast(it->SectionData->getSection()); +void MachObjectWriter::computeSectionAddresses(const MCAssembler &Asm, + const MCAsmLayout &Layout) { + uint64_t StartAddress = 0; + const SmallVectorImpl &Order = Layout.getSectionOrder(); + for (int i = 0, n = Order.size(); i != n ; ++i) { + const MCSectionData *SD = Order[i]; + StartAddress = RoundUpToAlignment(StartAddress, SD->getAlignment()); + SectionAddress[SD] = StartAddress; + StartAddress += Layout.getSectionAddressSize(SD); + + // Explicitly pad the section to match the alignment requirements of the + // following one. This is for 'gas' compatibility, it shouldn't + /// strictly be necessary. + StartAddress += getPaddingSize(SD, Layout); + } +} - if (Section.getType() != MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS) - continue; +void MachObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm, + const MCAsmLayout &Layout) { + computeSectionAddresses(Asm, Layout); - // Initialize the section indirect symbol base, if necessary. - if (!IndirectSymBase.count(it->SectionData)) - IndirectSymBase[it->SectionData] = IndirectIndex; - - Asm.getOrCreateSymbolData(*it->Symbol); - } + // Create symbol data for any indirect symbols. + BindIndirectSymbols(Asm); - // Then lazy symbol pointers and symbol stubs. - IndirectIndex = 0; - for (MCAssembler::indirect_symbol_iterator it = Asm.indirect_symbol_begin(), - ie = Asm.indirect_symbol_end(); it != ie; ++it, ++IndirectIndex) { - const MCSectionMachO &Section = - cast(it->SectionData->getSection()); - - if (Section.getType() != MCSectionMachO::S_LAZY_SYMBOL_POINTERS && - Section.getType() != MCSectionMachO::S_SYMBOL_STUBS) - continue; - - // Initialize the section indirect symbol base, if necessary. - if (!IndirectSymBase.count(it->SectionData)) - IndirectSymBase[it->SectionData] = IndirectIndex; - - // Set the symbol type to undefined lazy, but only on construction. - // - // FIXME: Do not hardcode. - bool Created; - MCSymbolData &Entry = Asm.getOrCreateSymbolData(*it->Symbol, &Created); - if (Created) - Entry.setFlags(Entry.getFlags() | 0x0001); - } - } + // Compute symbol table information and bind symbol indices. + ComputeSymbolTable(Asm, StringTable, LocalSymbolData, ExternalSymbolData, + UndefinedSymbolData); +} - /// ComputeSymbolTable - Compute the symbol table data - /// - /// \param StringTable [out] - The string table data. - /// \param StringIndexMap [out] - Map from symbol names to offsets in the - /// string table. - void ComputeSymbolTable(MCAssembler &Asm, SmallString<256> &StringTable, - std::vector &LocalSymbolData, - std::vector &ExternalSymbolData, - std::vector &UndefinedSymbolData) { - // Build section lookup table. - DenseMap SectionIndexMap; - unsigned Index = 1; - for (MCAssembler::iterator it = Asm.begin(), - ie = Asm.end(); it != ie; ++it, ++Index) - SectionIndexMap[&it->getSection()] = Index; - assert(Index <= 256 && "Too many sections!"); - - // Index 0 is always the empty string. - StringMap StringIndexMap; - StringTable += '\x00'; +bool MachObjectWriter:: +IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, + const MCSymbolData &DataA, + const MCFragment &FB, + bool InSet, + bool IsPCRel) const { + if (InSet) + return true; - // Build the symbol arrays and the string table, but only for non-local - // symbols. - // - // The particular order that we collect the symbols and create the string - // table, then sort the symbols is chosen to match 'as'. Even though it - // doesn't matter for correctness, this is important for letting us diff .o - // files. - for (MCAssembler::symbol_iterator it = Asm.symbol_begin(), - ie = Asm.symbol_end(); it != ie; ++it) { - const MCSymbol &Symbol = it->getSymbol(); - - // Ignore non-linker visible symbols. - if (!Asm.isSymbolLinkerVisible(it->getSymbol())) - continue; - - if (!it->isExternal() && !Symbol.isUndefined()) - continue; - - uint64_t &Entry = StringIndexMap[Symbol.getName()]; - if (!Entry) { - Entry = StringTable.size(); - StringTable += Symbol.getName(); - StringTable += '\x00'; - } + // The effective address is + // addr(atom(A)) + offset(A) + // - addr(atom(B)) - offset(B) + // and the offsets are not relocatable, so the fixup is fully resolved when + // addr(atom(A)) - addr(atom(B)) == 0. + const MCSymbolData *A_Base = 0, *B_Base = 0; - MachSymbolData MSD; - MSD.SymbolData = it; - MSD.StringIndex = Entry; - - if (Symbol.isUndefined()) { - MSD.SectionIndex = 0; - UndefinedSymbolData.push_back(MSD); - } else if (Symbol.isAbsolute()) { - MSD.SectionIndex = 0; - ExternalSymbolData.push_back(MSD); - } else { - MSD.SectionIndex = SectionIndexMap.lookup(&Symbol.getSection()); - assert(MSD.SectionIndex && "Invalid section index!"); - ExternalSymbolData.push_back(MSD); - } + const MCSymbol &SA = DataA.getSymbol().AliasedSymbol(); + const MCSection &SecA = SA.getSection(); + const MCSection &SecB = FB.getParent()->getSection(); + + if (IsPCRel) { + // The simple (Darwin, except on x86_64) way of dealing with this was to + // assume that any reference to a temporary symbol *must* be a temporary + // symbol in the same atom, unless the sections differ. Therefore, any PCrel + // relocation to a temporary symbol (in the same section) is fully + // resolved. This also works in conjunction with absolutized .set, which + // requires the compiler to use .set to absolutize the differences between + // symbols which the compiler knows to be assembly time constants, so we + // don't need to worry about considering symbol differences fully resolved. + // + // If the file isn't using sub-sections-via-symbols, we can make the + // same assumptions about any symbol that we normally make about + // assembler locals. + + if (!Asm.getBackend().hasReliableSymbolDifference()) { + if (!SA.isInSection() || &SecA != &SecB || + (!SA.isTemporary() && &FB != Asm.getSymbolData(SA).getFragment())) + return false; + return true; } + // For Darwin x86_64, there is one special case when the reference IsPCRel. + // If the fragment with the reference does not have a base symbol but meets + // the simple way of dealing with this, in that it is a temporary symbol in + // the same atom then it is assumed to be fully resolved. This is needed so + // a relocation entry is not created and so the static linker does not + // mess up the reference later. + else if(!FB.getAtom() && + SA.isTemporary() && SA.isInSection() && &SecA == &SecB){ + return true; + } + } else { + if (!TargetObjectWriter->useAggressiveSymbolFolding()) + return false; + } - // Now add the data for local symbols. - for (MCAssembler::symbol_iterator it = Asm.symbol_begin(), - ie = Asm.symbol_end(); it != ie; ++it) { - const MCSymbol &Symbol = it->getSymbol(); - - // Ignore non-linker visible symbols. - if (!Asm.isSymbolLinkerVisible(it->getSymbol())) - continue; + const MCFragment *FA = Asm.getSymbolData(SA).getFragment(); - if (it->isExternal() || Symbol.isUndefined()) - continue; + // Bail if the symbol has no fragment. + if (!FA) + return false; - uint64_t &Entry = StringIndexMap[Symbol.getName()]; - if (!Entry) { - Entry = StringTable.size(); - StringTable += Symbol.getName(); - StringTable += '\x00'; - } + A_Base = FA->getAtom(); + if (!A_Base) + return false; - MachSymbolData MSD; - MSD.SymbolData = it; - MSD.StringIndex = Entry; - - if (Symbol.isAbsolute()) { - MSD.SectionIndex = 0; - LocalSymbolData.push_back(MSD); - } else { - MSD.SectionIndex = SectionIndexMap.lookup(&Symbol.getSection()); - assert(MSD.SectionIndex && "Invalid section index!"); - LocalSymbolData.push_back(MSD); - } - } + B_Base = FB.getAtom(); + if (!B_Base) + return false; - // External and undefined symbols are required to be in lexicographic order. - std::sort(ExternalSymbolData.begin(), ExternalSymbolData.end()); - std::sort(UndefinedSymbolData.begin(), UndefinedSymbolData.end()); + // If the atoms are the same, they are guaranteed to have the same address. + if (A_Base == B_Base) + return true; - // Set the symbol indices. - Index = 0; - for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i) - LocalSymbolData[i].SymbolData->setIndex(Index++); - for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i) - ExternalSymbolData[i].SymbolData->setIndex(Index++); - for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i) - UndefinedSymbolData[i].SymbolData->setIndex(Index++); + // Otherwise, we can't prove this is fully resolved. + return false; +} - // The string table is padded to a multiple of 4. - while (StringTable.size() % 4) - StringTable += '\x00'; +void MachObjectWriter::WriteObject(MCAssembler &Asm, + const MCAsmLayout &Layout) { + unsigned NumSections = Asm.size(); + + // The section data starts after the header, the segment load command (and + // section headers) and the symbol table. + unsigned NumLoadCommands = 1; + uint64_t LoadCommandsSize = is64Bit() ? + macho::SegmentLoadCommand64Size + NumSections * macho::Section64Size : + macho::SegmentLoadCommand32Size + NumSections * macho::Section32Size; + + // Add the symbol table load command sizes, if used. + unsigned NumSymbols = LocalSymbolData.size() + ExternalSymbolData.size() + + UndefinedSymbolData.size(); + if (NumSymbols) { + NumLoadCommands += 2; + LoadCommandsSize += (macho::SymtabLoadCommandSize + + macho::DysymtabLoadCommandSize); } - void ExecutePostLayoutBinding(MCAssembler &Asm) { - // Create symbol data for any indirect symbols. - BindIndirectSymbols(Asm); - - // Compute symbol table information and bind symbol indices. - ComputeSymbolTable(Asm, StringTable, LocalSymbolData, ExternalSymbolData, - UndefinedSymbolData); + // Compute the total size of the section data, as well as its file size and vm + // size. + uint64_t SectionDataStart = (is64Bit() ? macho::Header64Size : + macho::Header32Size) + LoadCommandsSize; + uint64_t SectionDataSize = 0; + uint64_t SectionDataFileSize = 0; + uint64_t VMSize = 0; + for (MCAssembler::const_iterator it = Asm.begin(), + ie = Asm.end(); it != ie; ++it) { + const MCSectionData &SD = *it; + uint64_t Address = getSectionAddress(&SD); + uint64_t Size = Layout.getSectionAddressSize(&SD); + uint64_t FileSize = Layout.getSectionFileSize(&SD); + FileSize += getPaddingSize(&SD, Layout); + + VMSize = std::max(VMSize, Address + Size); + + if (SD.getSection().isVirtualSection()) + continue; + + SectionDataSize = std::max(SectionDataSize, Address + Size); + SectionDataFileSize = std::max(SectionDataFileSize, Address + FileSize); } - - bool IsFixupFullyResolved(const MCAssembler &Asm, - const MCValue Target, - bool IsPCRel, - const MCFragment *DF) const { - // If we are using scattered symbols, determine whether this value is - // actually resolved; scattering may cause atoms to move. - if (Asm.getBackend().hasScatteredSymbols()) { - if (Asm.getBackend().hasReliableSymbolDifference()) { - // If this is a PCrel relocation, find the base atom (identified by its - // symbol) that the fixup value is relative to. - const MCSymbolData *BaseSymbol = 0; - if (IsPCRel) { - BaseSymbol = DF->getAtom(); - if (!BaseSymbol) - return false; - } - - return isScatteredFixupFullyResolved(Asm, Target, BaseSymbol); - } else { - const MCSection *BaseSection = 0; - if (IsPCRel) - BaseSection = &DF->getParent()->getSection(); - - return isScatteredFixupFullyResolvedSimple(Asm, Target, BaseSection); - } - } - return true; + // The section data is padded to 4 bytes. + // + // FIXME: Is this machine dependent? + unsigned SectionDataPadding = OffsetToAlignment(SectionDataFileSize, 4); + SectionDataFileSize += SectionDataPadding; + + // Write the prolog, starting with the header and load command... + WriteHeader(NumLoadCommands, LoadCommandsSize, + Asm.getSubsectionsViaSymbols()); + WriteSegmentLoadCommand(NumSections, VMSize, + SectionDataStart, SectionDataSize); + + // ... and then the section headers. + uint64_t RelocTableEnd = SectionDataStart + SectionDataFileSize; + for (MCAssembler::const_iterator it = Asm.begin(), + ie = Asm.end(); it != ie; ++it) { + std::vector &Relocs = Relocations[it]; + unsigned NumRelocs = Relocs.size(); + uint64_t SectionStart = SectionDataStart + getSectionAddress(it); + WriteSection(Asm, Layout, *it, SectionStart, RelocTableEnd, NumRelocs); + RelocTableEnd += NumRelocs * macho::RelocationInfoSize; } - void WriteObject(const MCAssembler &Asm, const MCAsmLayout &Layout) { - unsigned NumSections = Asm.size(); - - // The section data starts after the header, the segment load command (and - // section headers) and the symbol table. - unsigned NumLoadCommands = 1; - uint64_t LoadCommandsSize = Is64Bit ? - SegmentLoadCommand64Size + NumSections * Section64Size : - SegmentLoadCommand32Size + NumSections * Section32Size; - - // Add the symbol table load command sizes, if used. - unsigned NumSymbols = LocalSymbolData.size() + ExternalSymbolData.size() + - UndefinedSymbolData.size(); - if (NumSymbols) { - NumLoadCommands += 2; - LoadCommandsSize += SymtabLoadCommandSize + DysymtabLoadCommandSize; - } + // Write the symbol table load command, if used. + if (NumSymbols) { + unsigned FirstLocalSymbol = 0; + unsigned NumLocalSymbols = LocalSymbolData.size(); + unsigned FirstExternalSymbol = FirstLocalSymbol + NumLocalSymbols; + unsigned NumExternalSymbols = ExternalSymbolData.size(); + unsigned FirstUndefinedSymbol = FirstExternalSymbol + NumExternalSymbols; + unsigned NumUndefinedSymbols = UndefinedSymbolData.size(); + unsigned NumIndirectSymbols = Asm.indirect_symbol_size(); + unsigned NumSymTabSymbols = + NumLocalSymbols + NumExternalSymbols + NumUndefinedSymbols; + uint64_t IndirectSymbolSize = NumIndirectSymbols * 4; + uint64_t IndirectSymbolOffset = 0; + + // If used, the indirect symbols are written after the section data. + if (NumIndirectSymbols) + IndirectSymbolOffset = RelocTableEnd; + + // The symbol table is written after the indirect symbol data. + uint64_t SymbolTableOffset = RelocTableEnd + IndirectSymbolSize; + + // The string table is written after symbol table. + uint64_t StringTableOffset = + SymbolTableOffset + NumSymTabSymbols * (is64Bit() ? macho::Nlist64Size : + macho::Nlist32Size); + WriteSymtabLoadCommand(SymbolTableOffset, NumSymTabSymbols, + StringTableOffset, StringTable.size()); + + WriteDysymtabLoadCommand(FirstLocalSymbol, NumLocalSymbols, + FirstExternalSymbol, NumExternalSymbols, + FirstUndefinedSymbol, NumUndefinedSymbols, + IndirectSymbolOffset, NumIndirectSymbols); + } - // Compute the total size of the section data, as well as its file size and - // vm size. - uint64_t SectionDataStart = (Is64Bit ? Header64Size : Header32Size) - + LoadCommandsSize; - uint64_t SectionDataSize = 0; - uint64_t SectionDataFileSize = 0; - uint64_t VMSize = 0; - for (MCAssembler::const_iterator it = Asm.begin(), - ie = Asm.end(); it != ie; ++it) { - const MCSectionData &SD = *it; - uint64_t Address = Layout.getSectionAddress(&SD); - uint64_t Size = Layout.getSectionSize(&SD); - uint64_t FileSize = Layout.getSectionFileSize(&SD); - - VMSize = std::max(VMSize, Address + Size); - - if (Asm.getBackend().isVirtualSection(SD.getSection())) - continue; - - SectionDataSize = std::max(SectionDataSize, Address + Size); - SectionDataFileSize = std::max(SectionDataFileSize, Address + FileSize); - } + // Write the actual section data. + for (MCAssembler::const_iterator it = Asm.begin(), + ie = Asm.end(); it != ie; ++it) { + Asm.writeSectionData(it, Layout); - // The section data is padded to 4 bytes. - // - // FIXME: Is this machine dependent? - unsigned SectionDataPadding = OffsetToAlignment(SectionDataFileSize, 4); - SectionDataFileSize += SectionDataPadding; - - // Write the prolog, starting with the header and load command... - WriteHeader(NumLoadCommands, LoadCommandsSize, - Asm.getSubsectionsViaSymbols()); - WriteSegmentLoadCommand(NumSections, VMSize, - SectionDataStart, SectionDataSize); - - // ... and then the section headers. - uint64_t RelocTableEnd = SectionDataStart + SectionDataFileSize; - for (MCAssembler::const_iterator it = Asm.begin(), - ie = Asm.end(); it != ie; ++it) { - std::vector &Relocs = Relocations[it]; - unsigned NumRelocs = Relocs.size(); - uint64_t SectionStart = SectionDataStart + Layout.getSectionAddress(it); - WriteSection(Asm, Layout, *it, SectionStart, RelocTableEnd, NumRelocs); - RelocTableEnd += NumRelocs * RelocationInfoSize; - } + uint64_t Pad = getPaddingSize(it, Layout); + for (unsigned int i = 0; i < Pad; ++i) + Write8(0); + } - // Write the symbol table load command, if used. - if (NumSymbols) { - unsigned FirstLocalSymbol = 0; - unsigned NumLocalSymbols = LocalSymbolData.size(); - unsigned FirstExternalSymbol = FirstLocalSymbol + NumLocalSymbols; - unsigned NumExternalSymbols = ExternalSymbolData.size(); - unsigned FirstUndefinedSymbol = FirstExternalSymbol + NumExternalSymbols; - unsigned NumUndefinedSymbols = UndefinedSymbolData.size(); - unsigned NumIndirectSymbols = Asm.indirect_symbol_size(); - unsigned NumSymTabSymbols = - NumLocalSymbols + NumExternalSymbols + NumUndefinedSymbols; - uint64_t IndirectSymbolSize = NumIndirectSymbols * 4; - uint64_t IndirectSymbolOffset = 0; - - // If used, the indirect symbols are written after the section data. - if (NumIndirectSymbols) - IndirectSymbolOffset = RelocTableEnd; - - // The symbol table is written after the indirect symbol data. - uint64_t SymbolTableOffset = RelocTableEnd + IndirectSymbolSize; - - // The string table is written after symbol table. - uint64_t StringTableOffset = - SymbolTableOffset + NumSymTabSymbols * (Is64Bit ? Nlist64Size : - Nlist32Size); - WriteSymtabLoadCommand(SymbolTableOffset, NumSymTabSymbols, - StringTableOffset, StringTable.size()); - - WriteDysymtabLoadCommand(FirstLocalSymbol, NumLocalSymbols, - FirstExternalSymbol, NumExternalSymbols, - FirstUndefinedSymbol, NumUndefinedSymbols, - IndirectSymbolOffset, NumIndirectSymbols); - } - - // Write the actual section data. - for (MCAssembler::const_iterator it = Asm.begin(), - ie = Asm.end(); it != ie; ++it) - Asm.WriteSectionData(it, Layout, Writer); - - // Write the extra padding. - WriteZeros(SectionDataPadding); - - // Write the relocation entries. - for (MCAssembler::const_iterator it = Asm.begin(), - ie = Asm.end(); it != ie; ++it) { - // Write the section relocation entries, in reverse order to match 'as' - // (approximately, the exact algorithm is more complicated than this). - std::vector &Relocs = Relocations[it]; - for (unsigned i = 0, e = Relocs.size(); i != e; ++i) { - Write32(Relocs[e - i - 1].Word0); - Write32(Relocs[e - i - 1].Word1); - } + // Write the extra padding. + WriteZeros(SectionDataPadding); + + // Write the relocation entries. + for (MCAssembler::const_iterator it = Asm.begin(), + ie = Asm.end(); it != ie; ++it) { + // Write the section relocation entries, in reverse order to match 'as' + // (approximately, the exact algorithm is more complicated than this). + std::vector &Relocs = Relocations[it]; + for (unsigned i = 0, e = Relocs.size(); i != e; ++i) { + Write32(Relocs[e - i - 1].Word0); + Write32(Relocs[e - i - 1].Word1); } + } - // Write the symbol table data, if used. - if (NumSymbols) { - // Write the indirect symbol entries. - for (MCAssembler::const_indirect_symbol_iterator - it = Asm.indirect_symbol_begin(), - ie = Asm.indirect_symbol_end(); it != ie; ++it) { - // Indirect symbols in the non lazy symbol pointer section have some - // special handling. - const MCSectionMachO &Section = - static_cast(it->SectionData->getSection()); - if (Section.getType() == MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS) { - // If this symbol is defined and internal, mark it as such. - if (it->Symbol->isDefined() && - !Asm.getSymbolData(*it->Symbol).isExternal()) { - uint32_t Flags = ISF_Local; - if (it->Symbol->isAbsolute()) - Flags |= ISF_Absolute; - Write32(Flags); - continue; - } + // Write the symbol table data, if used. + if (NumSymbols) { + // Write the indirect symbol entries. + for (MCAssembler::const_indirect_symbol_iterator + it = Asm.indirect_symbol_begin(), + ie = Asm.indirect_symbol_end(); it != ie; ++it) { + // Indirect symbols in the non lazy symbol pointer section have some + // special handling. + const MCSectionMachO &Section = + static_cast(it->SectionData->getSection()); + if (Section.getType() == MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS) { + // If this symbol is defined and internal, mark it as such. + if (it->Symbol->isDefined() && + !Asm.getSymbolData(*it->Symbol).isExternal()) { + uint32_t Flags = macho::ISF_Local; + if (it->Symbol->isAbsolute()) + Flags |= macho::ISF_Absolute; + Write32(Flags); + continue; } - - Write32(Asm.getSymbolData(*it->Symbol).getIndex()); } - // FIXME: Check that offsets match computed ones. - - // Write the symbol table entries. - for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i) - WriteNlist(LocalSymbolData[i], Layout); - for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i) - WriteNlist(ExternalSymbolData[i], Layout); - for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i) - WriteNlist(UndefinedSymbolData[i], Layout); - - // Write the string table. - OS << StringTable.str(); + Write32(Asm.getSymbolData(*it->Symbol).getIndex()); } - } -}; - -} - -MachObjectWriter::MachObjectWriter(raw_ostream &OS, - bool Is64Bit, - bool IsLittleEndian) - : MCObjectWriter(OS, IsLittleEndian) -{ - Impl = new MachObjectWriterImpl(this, Is64Bit); -} - -MachObjectWriter::~MachObjectWriter() { - delete (MachObjectWriterImpl*) Impl; -} -void MachObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm) { - ((MachObjectWriterImpl*) Impl)->ExecutePostLayoutBinding(Asm); -} + // FIXME: Check that offsets match computed ones. -void MachObjectWriter::RecordRelocation(const MCAssembler &Asm, - const MCAsmLayout &Layout, - const MCFragment *Fragment, - const MCFixup &Fixup, MCValue Target, - uint64_t &FixedValue) { - ((MachObjectWriterImpl*) Impl)->RecordRelocation(Asm, Layout, Fragment, Fixup, - Target, FixedValue); -} + // Write the symbol table entries. + for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i) + WriteNlist(LocalSymbolData[i], Layout); + for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i) + WriteNlist(ExternalSymbolData[i], Layout); + for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i) + WriteNlist(UndefinedSymbolData[i], Layout); -bool MachObjectWriter::IsFixupFullyResolved(const MCAssembler &Asm, - const MCValue Target, - bool IsPCRel, - const MCFragment *DF) const { - return ((MachObjectWriterImpl*) Impl)->IsFixupFullyResolved(Asm, Target, - IsPCRel, DF); + // Write the string table. + OS << StringTable.str(); + } } -void MachObjectWriter::WriteObject(const MCAssembler &Asm, - const MCAsmLayout &Layout) { - ((MachObjectWriterImpl*) Impl)->WriteObject(Asm, Layout); +MCObjectWriter *llvm::createMachObjectWriter(MCMachObjectTargetWriter *MOTW, + raw_ostream &OS, + bool IsLittleEndian) { + return new MachObjectWriter(MOTW, OS, IsLittleEndian); }