X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FMCAssembler.cpp;h=7d8455492780caef76a3cc5ded58c37b6ab8e21d;hb=6d8cf082f643a585b82e8dd136641ee4638b8c7a;hp=dae2d9336cbb5f99f9e9b6d5198aecad6158257b;hpb=ee0d89245eabf93d89b5fef7ac8707680796826d;p=oota-llvm.git diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp index dae2d9336cb..7d845549278 100644 --- a/lib/MC/MCAssembler.cpp +++ b/lib/MC/MCAssembler.cpp @@ -10,945 +10,168 @@ #define DEBUG_TYPE "assembler" #include "llvm/MC/MCAssembler.h" #include "llvm/MC/MCAsmLayout.h" +#include "llvm/MC/MCCodeEmitter.h" #include "llvm/MC/MCExpr.h" -#include "llvm/MC/MCSectionMachO.h" +#include "llvm/MC/MCObjectWriter.h" #include "llvm/MC/MCSymbol.h" #include "llvm/MC/MCValue.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/OwningPtr.h" #include "llvm/ADT/Statistic.h" #include "llvm/ADT/StringExtras.h" -#include "llvm/ADT/StringMap.h" #include "llvm/ADT/Twine.h" +#include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" -#include "llvm/Support/MachO.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/Support/Debug.h" #include "llvm/Target/TargetRegistry.h" #include "llvm/Target/TargetAsmBackend.h" -// FIXME: Gross. -#include "../Target/X86/X86FixupKinds.h" - #include using namespace llvm; -class MachObjectWriter; - +namespace { +namespace stats { STATISTIC(EmittedFragments, "Number of emitted assembler fragments"); +STATISTIC(EvaluateFixup, "Number of evaluated fixups"); +STATISTIC(FragmentLayouts, "Number of fragment layouts"); +STATISTIC(ObjectBytes, "Number of emitted object file bytes"); +STATISTIC(RelaxationSteps, "Number of assembler layout and relaxation steps"); +STATISTIC(RelaxedInstructions, "Number of relaxed instructions"); +STATISTIC(SectionLayouts, "Number of section layouts"); +} +} // FIXME FIXME FIXME: There are number of places in this file where we convert // what is a 64-bit assembler value used for computation into a value in the // object file, which may truncate it. We should detect that truncation where // invalid and report errors back. -static void WriteFileData(raw_ostream &OS, const MCSectionData &SD, - MachObjectWriter &MOW); - -static uint64_t WriteNopData(uint64_t Count, MachObjectWriter &MOW); - -/// isVirtualSection - Check if this is a section which does not actually exist -/// in the object file. -static bool isVirtualSection(const MCSection &Section) { - // FIXME: Lame. - const MCSectionMachO &SMO = static_cast(Section); - unsigned Type = SMO.getTypeAndAttributes() & MCSectionMachO::SECTION_TYPE; - return (Type == MCSectionMachO::S_ZEROFILL); -} +/* *** */ -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 FK_Data_2: return 1; - case X86::reloc_pcrel_4byte: - case X86::reloc_riprel_4byte: - case FK_Data_4: return 2; - case FK_Data_8: return 3; - } +MCAsmLayout::MCAsmLayout(MCAssembler &Asm) + : Assembler(Asm), LastValidFragment(0) + { + // Compute the section layout order. Virtual sections must go last. + for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) + if (!Asm.getBackend().isVirtualSection(it->getSection())) + SectionOrder.push_back(&*it); + for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) + if (Asm.getBackend().isVirtualSection(it->getSection())) + SectionOrder.push_back(&*it); } -static bool isFixupKindPCRel(unsigned Kind) { - switch (Kind) { - default: - return false; - case X86::reloc_pcrel_1byte: - case X86::reloc_pcrel_4byte: - case X86::reloc_riprel_4byte: +bool MCAsmLayout::isSectionUpToDate(const MCSectionData *SD) const { + // The first section is always up-to-date. + unsigned Index = SD->getLayoutOrder(); + if (!Index) return true; - } -} - -class MachObjectWriter { - // 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 - }; - - /// 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 { - const std::string &Name = SymbolData->getSymbol().getName(); - return Name < RHS.SymbolData->getSymbol().getName(); - } - }; - - raw_ostream &OS; - unsigned Is64Bit : 1; - unsigned IsLSB : 1; - -public: - MachObjectWriter(raw_ostream &_OS, bool _Is64Bit, bool _IsLSB = true) - : OS(_OS), Is64Bit(_Is64Bit), IsLSB(_IsLSB) { - } - - /// @name Helper Methods - /// @{ - - void Write8(uint8_t Value) { - OS << char(Value); - } - - void Write16(uint16_t Value) { - if (IsLSB) { - Write8(uint8_t(Value >> 0)); - Write8(uint8_t(Value >> 8)); - } else { - Write8(uint8_t(Value >> 8)); - Write8(uint8_t(Value >> 0)); - } - } - - void Write32(uint32_t Value) { - if (IsLSB) { - Write16(uint16_t(Value >> 0)); - Write16(uint16_t(Value >> 16)); - } else { - Write16(uint16_t(Value >> 16)); - Write16(uint16_t(Value >> 0)); - } - } - - void Write64(uint64_t Value) { - if (IsLSB) { - Write32(uint32_t(Value >> 0)); - Write32(uint32_t(Value >> 32)); - } else { - Write32(uint32_t(Value >> 32)); - Write32(uint32_t(Value >> 0)); - } - } - - void WriteZeros(unsigned N) { - const char Zeros[16] = { 0 }; - - for (unsigned i = 0, e = N / 16; i != e; ++i) - OS << StringRef(Zeros, 16); - - OS << StringRef(Zeros, N % 16); - } - - void WriteString(StringRef Str, unsigned ZeroFillSize = 0) { - OS << Str; - if (ZeroFillSize) - WriteZeros(ZeroFillSize - Str.size()); - } - - /// @} - - void WriteHeader(unsigned NumLoadCommands, unsigned LoadCommandsSize, - bool SubsectionsViaSymbols) { - uint32_t Flags = 0; - - if (SubsectionsViaSymbols) - Flags |= HF_SubsectionsViaSymbols; - - // struct mach_header (28 bytes) or - // struct mach_header_64 (32 bytes) - - uint64_t Start = OS.tell(); - (void) Start; - - Write32(Is64Bit ? Header_Magic64 : Header_Magic32); - - // 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 - - assert(OS.tell() - Start == Is64Bit ? Header64Size : Header32Size); - } - - /// 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)); - - WriteString("", 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 - - assert(OS.tell() - Start == SegmentLoadCommandSize); - } - - void WriteSection(const MCSectionData &SD, uint64_t FileOffset, - uint64_t RelocationsStart, unsigned NumRelocations) { - // The offset is unused for virtual sections. - if (isVirtualSection(SD.getSection())) { - assert(SD.getFileSize() == 0 && "Invalid file size!"); - FileOffset = 0; - } - - // struct section (68 bytes) or - // struct section_64 (80 bytes) - - uint64_t Start = OS.tell(); - (void) Start; - - // FIXME: cast<> support! - const MCSectionMachO &Section = - static_cast(SD.getSection()); - WriteString(Section.getSectionName(), 16); - WriteString(Section.getSegmentName(), 16); - if (Is64Bit) { - Write64(SD.getAddress()); // address - Write64(SD.getSize()); // size - } else { - Write32(SD.getAddress()); // address - Write32(SD.getSize()); // 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(0); // reserved1 - Write32(Section.getStubSize()); // reserved2 - if (Is64Bit) - Write32(0); // reserved3 - - assert(OS.tell() - Start == Is64Bit ? Section64Size : Section32Size); - } - - void WriteSymtabLoadCommand(uint32_t SymbolOffset, uint32_t NumSymbols, - uint32_t StringTableOffset, - uint32_t StringTableSize) { - // struct symtab_command (24 bytes) - - uint64_t Start = OS.tell(); - (void) Start; - - Write32(LCT_Symtab); - Write32(SymtabLoadCommandSize); - Write32(SymbolOffset); - Write32(NumSymbols); - Write32(StringTableOffset); - Write32(StringTableSize); - - assert(OS.tell() - Start == SymtabLoadCommandSize); - } - - 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); - } - - void WriteNlist32(MachSymbolData &MSD) { - 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()) { - llvm_unreachable("FIXME: Not yet implemented!"); - } else { - Address = Data.getAddress(); - } - } 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) - llvm_report_error("invalid 'common' alignment '" + - Twine(Align) + "'"); - // FIXME: Keep this mask with the SymbolFlags enumeration. - Flags = (Flags & 0xF0FF) | (Log2Size << 8); - } - } - - // struct nlist (12 bytes) - - Write32(MSD.StringIndex); - Write8(Type); - Write8(MSD.SectionIndex); - - // The Mach-O streamer uses the lowest 16-bits of the flags for the 'desc' - // value. - Write16(Flags); - Write32(Address); - } - - struct MachRelocationEntry { - uint32_t Word0; - uint32_t Word1; - }; - void ComputeScatteredRelocationInfo(MCAssembler &Asm, MCFragment &Fragment, - MCAsmFixup &Fixup, - const MCValue &Target, - std::vector &Relocs) { - uint32_t Address = Fragment.getOffset() + Fixup.Offset; - unsigned IsPCRel = isFixupKindPCRel(Fixup.Kind); - unsigned Log2Size = getFixupKindLog2Size(Fixup.Kind); - unsigned Type = RIT_Vanilla; - - // See . - const MCSymbol *A = Target.getSymA(); - MCSymbolData *A_SD = &Asm.getSymbolData(*A); - - if (!A_SD->getFragment()) - llvm_report_error("symbol '" + A->getName() + - "' can not be undefined in a subtraction expression"); - - uint32_t Value = A_SD->getAddress(); - uint32_t Value2 = 0; - - if (const MCSymbol *B = Target.getSymB()) { - MCSymbolData *B_SD = &Asm.getSymbolData(*B); - - if (!B_SD->getFragment()) - llvm_report_error("symbol '" + B->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 = B_SD->getAddress(); - } - MachRelocationEntry MRE; - MRE.Word0 = ((Address << 0) | - (Type << 24) | - (Log2Size << 28) | - (IsPCRel << 30) | - RF_Scattered); - MRE.Word1 = Value; - Relocs.push_back(MRE); - - 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; - Relocs.push_back(MRE); - } - } - - void ComputeRelocationInfo(MCAssembler &Asm, MCDataFragment &Fragment, - MCAsmFixup &Fixup, - std::vector &Relocs) { - unsigned IsPCRel = isFixupKindPCRel(Fixup.Kind); - unsigned Log2Size = getFixupKindLog2Size(Fixup.Kind); - - // FIXME: Share layout object. - MCAsmLayout Layout(Asm); - - // Evaluate the fixup; if the value was resolved, no relocation is needed. - MCValue Target; - if (Asm.EvaluateFixup(Layout, Fixup, &Fragment, Target, Fixup.FixedValue)) - return; - - // If this is a difference or a defined symbol plus an offset, then we need - // a scattered relocation entry. - uint32_t Offset = Target.getConstant(); - if (IsPCRel) - Offset += 1 << Log2Size; - if (Target.getSymB() || - (Target.getSymA() && !Target.getSymA()->isUndefined() && - Offset)) - return ComputeScatteredRelocationInfo(Asm, Fragment, Fixup, Target, - Relocs); - - // See . - uint32_t Address = Fragment.getOffset() + Fixup.Offset; - uint32_t Value = 0; - 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; - Value = 0; - } else { - const MCSymbol *Symbol = Target.getSymA(); - MCSymbolData *SD = &Asm.getSymbolData(*Symbol); - - if (Symbol->isUndefined()) { - IsExtern = 1; - Index = SD->getIndex(); - Value = 0; - } else { - // The index is the section ordinal. - // - // FIXME: O(N) - Index = 1; - MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); - for (; it != ie; ++it, ++Index) - if (&*it == SD->getFragment()->getParent()) - break; - assert(it != ie && "Unable to find section index!"); - Value = SD->getAddress(); - } - - Type = RIT_Vanilla; - } - - // struct relocation_info (8 bytes) - MachRelocationEntry MRE; - MRE.Word0 = Address; - MRE.Word1 = ((Index << 0) | - (IsPCRel << 24) | - (Log2Size << 25) | - (IsExtern << 27) | - (Type << 28)); - Relocs.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. - - // Bind non lazy symbol pointers first. - for (MCAssembler::indirect_symbol_iterator it = Asm.indirect_symbol_begin(), - ie = Asm.indirect_symbol_end(); it != ie; ++it) { - // FIXME: cast<> support! - const MCSectionMachO &Section = - static_cast(it->SectionData->getSection()); - - unsigned Type = - Section.getTypeAndAttributes() & MCSectionMachO::SECTION_TYPE; - if (Type != MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS) - continue; + // Otherwise, sections are always implicitly computed when the preceeding + // fragment is layed out. + const MCSectionData *Prev = getSectionOrder()[Index - 1]; + return isFragmentUpToDate(&(Prev->getFragmentList().back())); +} - Asm.getOrCreateSymbolData(*it->Symbol); - } +bool MCAsmLayout::isFragmentUpToDate(const MCFragment *F) const { + return (LastValidFragment && + F->getLayoutOrder() <= LastValidFragment->getLayoutOrder()); +} - // Then lazy symbol pointers and symbol stubs. - for (MCAssembler::indirect_symbol_iterator it = Asm.indirect_symbol_begin(), - ie = Asm.indirect_symbol_end(); it != ie; ++it) { - // FIXME: cast<> support! - const MCSectionMachO &Section = - static_cast(it->SectionData->getSection()); - - unsigned Type = - Section.getTypeAndAttributes() & MCSectionMachO::SECTION_TYPE; - if (Type != MCSectionMachO::S_LAZY_SYMBOL_POINTERS && - Type != MCSectionMachO::S_SYMBOL_STUBS) - continue; +void MCAsmLayout::UpdateForSlide(MCFragment *F, int SlideAmount) { + // If this fragment wasn't already up-to-date, we don't need to do anything. + if (!isFragmentUpToDate(F)) + return; - // 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); + // Otherwise, reset the last valid fragment to the predecessor of the + // invalidated fragment. + LastValidFragment = F->getPrevNode(); + if (!LastValidFragment) { + unsigned Index = F->getParent()->getLayoutOrder(); + if (Index != 0) { + MCSectionData *Prev = getSectionOrder()[Index - 1]; + LastValidFragment = &(Prev->getFragmentList().back()); } } +} - /// 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'; - - // 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 assembler temporaries. - if (it->getSymbol().isTemporary()) - continue; - - if (!it->isExternal() && !Symbol.isUndefined()) - continue; - - uint64_t &Entry = StringIndexMap[Symbol.getName()]; - if (!Entry) { - Entry = StringTable.size(); - StringTable += Symbol.getName(); - StringTable += '\x00'; - } - - 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); - } - } - - // 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 assembler temporaries. - if (it->getSymbol().isTemporary()) - continue; - - if (it->isExternal() || Symbol.isUndefined()) - continue; - - uint64_t &Entry = StringIndexMap[Symbol.getName()]; - if (!Entry) { - Entry = StringTable.size(); - StringTable += Symbol.getName(); - StringTable += '\x00'; - } - - 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); - } +void MCAsmLayout::EnsureValid(const MCFragment *F) const { + // Advance the layout position until the fragment is up-to-date. + while (!isFragmentUpToDate(F)) { + // Advance to the next fragment. + MCFragment *Cur = LastValidFragment; + if (Cur) + Cur = Cur->getNextNode(); + if (!Cur) { + unsigned NextIndex = 0; + if (LastValidFragment) + NextIndex = LastValidFragment->getParent()->getLayoutOrder() + 1; + Cur = SectionOrder[NextIndex]->begin(); } - // 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'; + const_cast(this)->LayoutFragment(Cur); } +} - void WriteObject(MCAssembler &Asm) { - unsigned NumSections = Asm.size(); - - // Create symbol data for any indirect symbols. - BindIndirectSymbols(Asm); - - // Compute symbol table information. - SmallString<256> StringTable; - std::vector LocalSymbolData; - std::vector ExternalSymbolData; - std::vector UndefinedSymbolData; - unsigned NumSymbols = Asm.symbol_size(); - - // No symbol table command is written if there are no symbols. - if (NumSymbols) - ComputeSymbolTable(Asm, StringTable, LocalSymbolData, ExternalSymbolData, - UndefinedSymbolData); - - // 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. - if (NumSymbols) { - NumLoadCommands += 2; - LoadCommandsSize += SymtabLoadCommandSize + DysymtabLoadCommandSize; - } - - // 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::iterator it = Asm.begin(), - ie = Asm.end(); it != ie; ++it) { - MCSectionData &SD = *it; - - VMSize = std::max(VMSize, SD.getAddress() + SD.getSize()); - - if (isVirtualSection(SD.getSection())) - continue; - - SectionDataSize = std::max(SectionDataSize, - SD.getAddress() + SD.getSize()); - SectionDataFileSize = std::max(SectionDataFileSize, - SD.getAddress() + SD.getFileSize()); - } - - // 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. - // - // We also compute the section relocations while we do this. Note that - // computing relocation info will also update the fixup to have the correct - // value; this will overwrite the appropriate data in the fragment when it - // is written. - std::vector RelocInfos; - uint64_t RelocTableEnd = SectionDataStart + SectionDataFileSize; - for (MCAssembler::iterator it = Asm.begin(), - ie = Asm.end(); it != ie; ++it) { - MCSectionData &SD = *it; - - // The assembler writes relocations in the reverse order they were seen. - // - // FIXME: It is probably more complicated than this. - unsigned NumRelocsStart = RelocInfos.size(); - for (MCSectionData::reverse_iterator it2 = SD.rbegin(), - ie2 = SD.rend(); it2 != ie2; ++it2) - if (MCDataFragment *DF = dyn_cast(&*it2)) - for (unsigned i = 0, e = DF->fixup_size(); i != e; ++i) - ComputeRelocationInfo(Asm, *DF, DF->getFixups()[e - i - 1], - RelocInfos); - - unsigned NumRelocs = RelocInfos.size() - NumRelocsStart; - uint64_t SectionStart = SectionDataStart + SD.getAddress(); - WriteSection(SD, SectionStart, RelocTableEnd, NumRelocs); - RelocTableEnd += NumRelocs * RelocationInfoSize; - } +void MCAsmLayout::FragmentReplaced(MCFragment *Src, MCFragment *Dst) { + if (LastValidFragment == Src) + LastValidFragment = Dst; - // 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 * Nlist32Size; - WriteSymtabLoadCommand(SymbolTableOffset, NumSymTabSymbols, - StringTableOffset, StringTable.size()); - - WriteDysymtabLoadCommand(FirstLocalSymbol, NumLocalSymbols, - FirstExternalSymbol, NumExternalSymbols, - FirstUndefinedSymbol, NumUndefinedSymbols, - IndirectSymbolOffset, NumIndirectSymbols); - } + Dst->Offset = Src->Offset; + Dst->EffectiveSize = Src->EffectiveSize; +} - // Write the actual section data. - for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) - WriteFileData(OS, *it, *this); +uint64_t MCAsmLayout::getFragmentAddress(const MCFragment *F) const { + assert(F->getParent() && "Missing section()!"); + return getSectionAddress(F->getParent()) + getFragmentOffset(F); +} - // Write the extra padding. - WriteZeros(SectionDataPadding); +uint64_t MCAsmLayout::getFragmentEffectiveSize(const MCFragment *F) const { + EnsureValid(F); + assert(F->EffectiveSize != ~UINT64_C(0) && "Address not set!"); + return F->EffectiveSize; +} - // Write the relocation entries. - for (unsigned i = 0, e = RelocInfos.size(); i != e; ++i) { - Write32(RelocInfos[i].Word0); - Write32(RelocInfos[i].Word1); - } +uint64_t MCAsmLayout::getFragmentOffset(const MCFragment *F) const { + EnsureValid(F); + assert(F->Offset != ~UINT64_C(0) && "Address not set!"); + return F->Offset; +} - // Write the symbol table data, if used. - if (NumSymbols) { - // Write the indirect symbol entries. - for (MCAssembler::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()); - unsigned Type = - Section.getTypeAndAttributes() & MCSectionMachO::SECTION_TYPE; - if (Type == 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; - } - } +uint64_t MCAsmLayout::getSymbolAddress(const MCSymbolData *SD) const { + assert(SD->getFragment() && "Invalid getAddress() on undefined symbol!"); + return getFragmentAddress(SD->getFragment()) + SD->getOffset(); +} - Write32(Asm.getSymbolData(*it->Symbol).getIndex()); - } +uint64_t MCAsmLayout::getSectionAddress(const MCSectionData *SD) const { + EnsureValid(SD->begin()); + assert(SD->Address != ~UINT64_C(0) && "Address not set!"); + return SD->Address; +} - // FIXME: Check that offsets match computed ones. +uint64_t MCAsmLayout::getSectionAddressSize(const MCSectionData *SD) const { + // The size is the last fragment's end offset. + const MCFragment &F = SD->getFragmentList().back(); + return getFragmentOffset(&F) + getFragmentEffectiveSize(&F); +} - // Write the symbol table entries. - for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i) - WriteNlist32(LocalSymbolData[i]); - for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i) - WriteNlist32(ExternalSymbolData[i]); - for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i) - WriteNlist32(UndefinedSymbolData[i]); +uint64_t MCAsmLayout::getSectionFileSize(const MCSectionData *SD) const { + // Virtual sections have no file size. + if (getAssembler().getBackend().isVirtualSection(SD->getSection())) + return 0; - // Write the string table. - OS << StringTable.str(); - } - } + // Otherwise, the file size is the same as the address space size. + return getSectionAddressSize(SD); +} - void ApplyFixup(const MCAsmFixup &Fixup, MCDataFragment &DF) { - unsigned Size = 1 << getFixupKindLog2Size(Fixup.Kind); +uint64_t MCAsmLayout::getSectionSize(const MCSectionData *SD) const { + // The logical size is the address space size minus any tail padding. + uint64_t Size = getSectionAddressSize(SD); + const MCAlignFragment *AF = + dyn_cast(&(SD->getFragmentList().back())); + if (AF && AF->hasOnlyAlignAddress()) + Size -= getFragmentEffectiveSize(AF); - // FIXME: Endianness assumption. - assert(Fixup.Offset + Size <= DF.getContents().size() && - "Invalid fixup offset!"); - for (unsigned i = 0; i != Size; ++i) - DF.getContents()[Fixup.Offset + i] = uint8_t(Fixup.FixedValue >> (i * 8)); - } -}; + return Size; +} /* *** */ @@ -956,22 +179,12 @@ MCFragment::MCFragment() : Kind(FragmentType(~0)) { } MCFragment::MCFragment(FragmentType _Kind, MCSectionData *_Parent) - : Kind(_Kind), - Parent(_Parent), - FileSize(~UINT64_C(0)) + : Kind(_Kind), Parent(_Parent), Atom(0), EffectiveSize(~UINT64_C(0)) { if (Parent) Parent->getFragmentList().push_back(this); } -MCFragment::~MCFragment() { -} - -uint64_t MCFragment::getAddress() const { - assert(getParent() && "Missing Section!"); - return getParent()->getAddress() + Offset; -} - /* *** */ MCSectionData::MCSectionData() : Section(0) {} @@ -980,8 +193,6 @@ MCSectionData::MCSectionData(const MCSection &_Section, MCAssembler *A) : Section(&_Section), Alignment(1), Address(~UINT64_C(0)), - Size(~UINT64_C(0)), - FileSize(~UINT64_C(0)), HasInstructions(false) { if (A) @@ -1005,19 +216,138 @@ MCSymbolData::MCSymbolData(const MCSymbol &_Symbol, MCFragment *_Fragment, /* *** */ MCAssembler::MCAssembler(MCContext &_Context, TargetAsmBackend &_Backend, - raw_ostream &_OS) - : Context(_Context), Backend(_Backend), OS(_OS), SubsectionsViaSymbols(false) + MCCodeEmitter &_Emitter, raw_ostream &_OS) + : Context(_Context), Backend(_Backend), Emitter(_Emitter), + OS(_OS), RelaxAll(false), SubsectionsViaSymbols(false) { } MCAssembler::~MCAssembler() { } -bool MCAssembler::EvaluateFixup(const MCAsmLayout &Layout, MCAsmFixup &Fixup, - MCDataFragment *DF, +static bool isScatteredFixupFullyResolvedSimple(const MCAssembler &Asm, + const MCFixup &Fixup, + 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; +} + +static bool isScatteredFixupFullyResolved(const MCAssembler &Asm, + const MCAsmLayout &Layout, + const MCFixup &Fixup, + 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. + + 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; + + A_Base = Asm.getAtom(Layout, &Asm.getSymbolData(A->getSymbol())); + if (!A_Base) + return false; + } + + if (const MCSymbolRefExpr *B = Target.getSymB()) { + // Modified symbol references cannot be resolved. + if (B->getKind() != MCSymbolRefExpr::VK_None) + return false; + + B_Base = Asm.getAtom(Layout, &Asm.getSymbolData(B->getSymbol())); + if (!B_Base) + return false; + } + + // 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; +} + +bool MCAssembler::isSymbolLinkerVisible(const MCSymbol &Symbol) const { + // Non-temporary labels should always be visible to the linker. + if (!Symbol.isTemporary()) + return true; + + // Absolute temporary labels are never visible. + if (!Symbol.isInSection()) + return false; + + // Otherwise, check if the section requires symbols even for temporary labels. + return getBackend().doesSectionRequireSymbols(Symbol.getSection()); +} + +const MCSymbolData *MCAssembler::getAtom(const MCAsmLayout &Layout, + const MCSymbolData *SD) const { + // Linker visible symbols define atoms. + if (isSymbolLinkerVisible(SD->getSymbol())) + return SD; + + // Absolute and undefined symbols have no defining atom. + if (!SD->getFragment()) + return 0; + + // Non-linker visible symbols in sections which can't be atomized have no + // defining atom. + if (!getBackend().isSectionAtomizable( + SD->getFragment()->getParent()->getSection())) + return 0; + + // Otherwise, return the atom for the containing fragment. + return SD->getFragment()->getAtom(); +} + +bool MCAssembler::EvaluateFixup(const MCAsmLayout &Layout, + const MCFixup &Fixup, const MCFragment *DF, MCValue &Target, uint64_t &Value) const { - if (!Fixup.Value->EvaluateAsRelocatable(Target, &Layout)) - llvm_report_error("expected relocatable expression"); + ++stats::EvaluateFixup; + + if (!Fixup.getValue()->EvaluateAsRelocatable(Target, &Layout)) + report_fatal_error("expected relocatable expression"); // FIXME: How do non-scattered symbols work in ELF? I presume the linker // doesn't support small relocations, but then under what criteria does the @@ -1025,208 +355,214 @@ bool MCAssembler::EvaluateFixup(const MCAsmLayout &Layout, MCAsmFixup &Fixup, Value = Target.getConstant(); - // FIXME: This "resolved" check isn't quite right. The assumption is that if - // we have a PCrel access to a temporary, then that temporary is in the same - // atom, and so the value is resolved. We need explicit atom's to implement - // this more precisely. - bool IsResolved = true, IsPCRel = isFixupKindPCRel(Fixup.Kind); - if (const MCSymbol *Symbol = Target.getSymA()) { - if (Symbol->isDefined()) - Value += getSymbolData(*Symbol).getAddress(); + bool IsPCRel = Emitter.getFixupKindInfo( + Fixup.getKind()).Flags & MCFixupKindInfo::FKF_IsPCRel; + bool IsResolved = true; + if (const MCSymbolRefExpr *A = Target.getSymA()) { + if (A->getSymbol().isDefined()) + Value += Layout.getSymbolAddress(&getSymbolData(A->getSymbol())); else IsResolved = false; - - // With scattered symbols, we assume anything that isn't a PCrel temporary - // access can have an arbitrary value. - if (getBackend().hasScatteredSymbols() && - (!IsPCRel || !Symbol->isTemporary())) - IsResolved = false; } - if (const MCSymbol *Symbol = Target.getSymB()) { - if (Symbol->isDefined()) - Value -= getSymbolData(*Symbol).getAddress(); + if (const MCSymbolRefExpr *B = Target.getSymB()) { + if (B->getSymbol().isDefined()) + Value -= Layout.getSymbolAddress(&getSymbolData(B->getSymbol())); else IsResolved = false; + } - // With scattered symbols, we assume anything that isn't a PCrel temporary - // access can have an arbitrary value. - if (getBackend().hasScatteredSymbols() && - (!IsPCRel || !Symbol->isTemporary())) - IsResolved = false; + // If we are using scattered symbols, determine whether this value is actually + // resolved; scattering may cause atoms to move. + if (IsResolved && getBackend().hasScatteredSymbols()) { + if (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) + IsResolved = false; + } + + if (IsResolved) + IsResolved = isScatteredFixupFullyResolved(*this, Layout, Fixup, Target, + BaseSymbol); + } else { + const MCSection *BaseSection = 0; + if (IsPCRel) + BaseSection = &DF->getParent()->getSection(); + + IsResolved = isScatteredFixupFullyResolvedSimple(*this, Fixup, Target, + BaseSection); + } } if (IsPCRel) - Value -= DF->getAddress() + Fixup.Offset; + Value -= Layout.getFragmentAddress(DF) + Fixup.getOffset(); return IsResolved; } -void MCAssembler::LayoutSection(MCSectionData &SD) { - MCAsmLayout Layout(*this); - uint64_t Address = SD.getAddress(); +uint64_t MCAssembler::ComputeFragmentSize(MCAsmLayout &Layout, + const MCFragment &F, + uint64_t SectionAddress, + uint64_t FragmentOffset) const { + switch (F.getKind()) { + case MCFragment::FT_Data: + return cast(F).getContents().size(); + case MCFragment::FT_Fill: + return cast(F).getSize(); + case MCFragment::FT_Inst: + return cast(F).getInstSize(); - for (MCSectionData::iterator it = SD.begin(), ie = SD.end(); it != ie; ++it) { - MCFragment &F = *it; + case MCFragment::FT_Align: { + const MCAlignFragment &AF = cast(F); - F.setOffset(Address - SD.getAddress()); + assert((!AF.hasOnlyAlignAddress() || !AF.getNextNode()) && + "Invalid OnlyAlignAddress bit, not the last fragment!"); - // Evaluate fragment size. - switch (F.getKind()) { - case MCFragment::FT_Align: { - MCAlignFragment &AF = cast(F); + uint64_t Size = OffsetToAlignment(SectionAddress + FragmentOffset, + AF.getAlignment()); - uint64_t Size = OffsetToAlignment(Address, AF.getAlignment()); - if (Size > AF.getMaxBytesToEmit()) - AF.setFileSize(0); - else - AF.setFileSize(Size); - break; - } + // Honor MaxBytesToEmit. + if (Size > AF.getMaxBytesToEmit()) + return 0; - case MCFragment::FT_Data: - case MCFragment::FT_Fill: - F.setFileSize(F.getMaxFileSize()); - break; - - case MCFragment::FT_Org: { - MCOrgFragment &OF = cast(F); + return Size; + } - int64_t TargetLocation; - if (!OF.getOffset().EvaluateAsAbsolute(TargetLocation, &Layout)) - llvm_report_error("expected assembly-time absolute expression"); + case MCFragment::FT_Org: { + const MCOrgFragment &OF = cast(F); - // FIXME: We need a way to communicate this error. - int64_t Offset = TargetLocation - F.getOffset(); - if (Offset < 0) - llvm_report_error("invalid .org offset '" + Twine(TargetLocation) + - "' (at offset '" + Twine(F.getOffset()) + "'"); + // FIXME: We should compute this sooner, we don't want to recurse here, and + // we would like to be more functional. + int64_t TargetLocation; + if (!OF.getOffset().EvaluateAsAbsolute(TargetLocation, &Layout)) + report_fatal_error("expected assembly-time absolute expression"); - F.setFileSize(Offset); - break; - } + // FIXME: We need a way to communicate this error. + int64_t Offset = TargetLocation - FragmentOffset; + if (Offset < 0) + report_fatal_error("invalid .org offset '" + Twine(TargetLocation) + + "' (at offset '" + Twine(FragmentOffset) + "'"); - case MCFragment::FT_ZeroFill: { - MCZeroFillFragment &ZFF = cast(F); + return Offset; + } + } - // Align the fragment offset; it is safe to adjust the offset freely since - // this is only in virtual sections. - Address = RoundUpToAlignment(Address, ZFF.getAlignment()); - F.setOffset(Address - SD.getAddress()); + assert(0 && "invalid fragment kind"); + return 0; +} - // FIXME: This is misnamed. - F.setFileSize(ZFF.getSize()); - break; - } - } +void MCAsmLayout::LayoutFile() { + // Initialize the first section and set the valid fragment layout point. All + // actual layout computations are done lazily. + LastValidFragment = 0; + if (!getSectionOrder().empty()) + getSectionOrder().front()->Address = 0; +} - Address += F.getFileSize(); +void MCAsmLayout::LayoutFragment(MCFragment *F) { + MCFragment *Prev = F->getPrevNode(); + + // We should never try to recompute something which is up-to-date. + assert(!isFragmentUpToDate(F) && "Attempt to recompute up-to-date fragment!"); + // We should never try to compute the fragment layout if the section isn't + // up-to-date. + assert(isSectionUpToDate(F->getParent()) && + "Attempt to compute fragment before it's section!"); + // We should never try to compute the fragment layout if it's predecessor + // isn't up-to-date. + assert((!Prev || isFragmentUpToDate(Prev)) && + "Attempt to compute fragment before it's predecessor!"); + + ++stats::FragmentLayouts; + + // Compute the fragment start address. + uint64_t StartAddress = F->getParent()->Address; + uint64_t Address = StartAddress; + if (Prev) + Address += Prev->Offset + Prev->EffectiveSize; + + // Compute fragment offset and size. + F->Offset = Address - StartAddress; + F->EffectiveSize = getAssembler().ComputeFragmentSize(*this, *F, StartAddress, + F->Offset); + LastValidFragment = F; + + // If this is the last fragment in a section, update the next section address. + if (!F->getNextNode()) { + unsigned NextIndex = F->getParent()->getLayoutOrder() + 1; + if (NextIndex != getSectionOrder().size()) + LayoutSection(getSectionOrder()[NextIndex]); } - - // Set the section sizes. - SD.setSize(Address - SD.getAddress()); - if (isVirtualSection(SD.getSection())) - SD.setFileSize(0); - else - SD.setFileSize(Address - SD.getAddress()); } -/// WriteNopData - Write optimal nops to the output file for the \arg Count -/// bytes. This returns the number of bytes written. It may return 0 if -/// the \arg Count is more than the maximum optimal nops. -/// -/// FIXME this is X86 32-bit specific and should move to a better place. -static uint64_t WriteNopData(uint64_t Count, MachObjectWriter &MOW) { - static const uint8_t Nops[16][16] = { - // nop - {0x90}, - // xchg %ax,%ax - {0x66, 0x90}, - // nopl (%[re]ax) - {0x0f, 0x1f, 0x00}, - // nopl 0(%[re]ax) - {0x0f, 0x1f, 0x40, 0x00}, - // nopl 0(%[re]ax,%[re]ax,1) - {0x0f, 0x1f, 0x44, 0x00, 0x00}, - // nopw 0(%[re]ax,%[re]ax,1) - {0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00}, - // nopl 0L(%[re]ax) - {0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00}, - // nopl 0L(%[re]ax,%[re]ax,1) - {0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00}, - // nopw 0L(%[re]ax,%[re]ax,1) - {0x66, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00}, - // nopw %cs:0L(%[re]ax,%[re]ax,1) - {0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00}, - // nopl 0(%[re]ax,%[re]ax,1) - // nopw 0(%[re]ax,%[re]ax,1) - {0x0f, 0x1f, 0x44, 0x00, 0x00, - 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00}, - // nopw 0(%[re]ax,%[re]ax,1) - // nopw 0(%[re]ax,%[re]ax,1) - {0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00, - 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00}, - // nopw 0(%[re]ax,%[re]ax,1) - // nopl 0L(%[re]ax) */ - {0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00, - 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00}, - // nopl 0L(%[re]ax) - // nopl 0L(%[re]ax) - {0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00, - 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00}, - // nopl 0L(%[re]ax) - // nopl 0L(%[re]ax,%[re]ax,1) - {0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00, - 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00} - }; - - if (Count > 15) - return 0; +void MCAsmLayout::LayoutSection(MCSectionData *SD) { + unsigned SectionOrderIndex = SD->getLayoutOrder(); - for (uint64_t i = 0; i < Count; i++) - MOW.Write8 (uint8_t(Nops[Count - 1][i])); + ++stats::SectionLayouts; - return Count; + // Compute the section start address. + uint64_t StartAddress = 0; + if (SectionOrderIndex) { + MCSectionData *Prev = getSectionOrder()[SectionOrderIndex - 1]; + StartAddress = getSectionAddress(Prev) + getSectionAddressSize(Prev); + } + + // Honor the section alignment requirements. + StartAddress = RoundUpToAlignment(StartAddress, SD->getAlignment()); + + // Set the section address. + SD->Address = StartAddress; } -/// WriteFileData - Write the \arg F data to the output file. -static void WriteFileData(raw_ostream &OS, const MCFragment &F, - MachObjectWriter &MOW) { - uint64_t Start = OS.tell(); +/// WriteFragmentData - Write the \arg F data to the output file. +static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, + const MCFragment &F, MCObjectWriter *OW) { + uint64_t Start = OW->getStream().tell(); (void) Start; - ++EmittedFragments; + ++stats::EmittedFragments; // FIXME: Embed in fragments instead? + uint64_t FragmentSize = Layout.getFragmentEffectiveSize(&F); switch (F.getKind()) { case MCFragment::FT_Align: { MCAlignFragment &AF = cast(F); - uint64_t Count = AF.getFileSize() / AF.getValueSize(); + uint64_t Count = FragmentSize / AF.getValueSize(); + + assert(AF.getValueSize() && "Invalid virtual align in concrete fragment!"); // FIXME: This error shouldn't actually occur (the front end should emit // multiple .align directives to enforce the semantics it wants), but is // severe enough that we want to report it. How to handle this? - if (Count * AF.getValueSize() != AF.getFileSize()) - llvm_report_error("undefined .align directive, value size '" + + if (Count * AF.getValueSize() != FragmentSize) + report_fatal_error("undefined .align directive, value size '" + Twine(AF.getValueSize()) + "' is not a divisor of padding size '" + - Twine(AF.getFileSize()) + "'"); + Twine(FragmentSize) + "'"); // See if we are aligning with nops, and if so do that first to try to fill // the Count bytes. Then if that did not fill any bytes or there are any // bytes left to fill use the the Value and ValueSize to fill the rest. - if (AF.getEmitNops()) { - uint64_t NopByteCount = WriteNopData(Count, MOW); - Count -= NopByteCount; + // If we are aligning with nops, ask that target to emit the right data. + if (AF.hasEmitNops()) { + if (!Asm.getBackend().WriteNopData(Count, OW)) + report_fatal_error("unable to write nop sequence of " + + Twine(Count) + " bytes"); + break; } + // Otherwise, write out in multiples of the value size. for (uint64_t i = 0; i != Count; ++i) { switch (AF.getValueSize()) { default: assert(0 && "Invalid size!"); - case 1: MOW.Write8 (uint8_t (AF.getValue())); break; - case 2: MOW.Write16(uint16_t(AF.getValue())); break; - case 4: MOW.Write32(uint32_t(AF.getValue())); break; - case 8: MOW.Write64(uint64_t(AF.getValue())); break; + case 1: OW->Write8 (uint8_t (AF.getValue())); break; + case 2: OW->Write16(uint16_t(AF.getValue())); break; + case 4: OW->Write32(uint32_t(AF.getValue())); break; + case 8: OW->Write64(uint64_t(AF.getValue())); break; } } break; @@ -1234,72 +570,81 @@ static void WriteFileData(raw_ostream &OS, const MCFragment &F, case MCFragment::FT_Data: { MCDataFragment &DF = cast(F); - - // Apply the fixups. - // - // FIXME: Move elsewhere. - for (MCDataFragment::const_fixup_iterator it = DF.fixup_begin(), - ie = DF.fixup_end(); it != ie; ++it) - MOW.ApplyFixup(*it, DF); - - OS << cast(F).getContents().str(); + assert(FragmentSize == DF.getContents().size() && "Invalid size!"); + OW->WriteBytes(DF.getContents().str()); break; } case MCFragment::FT_Fill: { MCFillFragment &FF = cast(F); - for (uint64_t i = 0, e = FF.getCount(); i != e; ++i) { + + assert(FF.getValueSize() && "Invalid virtual align in concrete fragment!"); + + for (uint64_t i = 0, e = FF.getSize() / FF.getValueSize(); i != e; ++i) { switch (FF.getValueSize()) { default: assert(0 && "Invalid size!"); - case 1: MOW.Write8 (uint8_t (FF.getValue())); break; - case 2: MOW.Write16(uint16_t(FF.getValue())); break; - case 4: MOW.Write32(uint32_t(FF.getValue())); break; - case 8: MOW.Write64(uint64_t(FF.getValue())); break; + case 1: OW->Write8 (uint8_t (FF.getValue())); break; + case 2: OW->Write16(uint16_t(FF.getValue())); break; + case 4: OW->Write32(uint32_t(FF.getValue())); break; + case 8: OW->Write64(uint64_t(FF.getValue())); break; } } break; } + case MCFragment::FT_Inst: + llvm_unreachable("unexpected inst fragment after lowering"); + break; + case MCFragment::FT_Org: { MCOrgFragment &OF = cast(F); - for (uint64_t i = 0, e = OF.getFileSize(); i != e; ++i) - MOW.Write8(uint8_t(OF.getValue())); + for (uint64_t i = 0, e = FragmentSize; i != e; ++i) + OW->Write8(uint8_t(OF.getValue())); break; } - - case MCFragment::FT_ZeroFill: { - assert(0 && "Invalid zero fill fragment in concrete section!"); - break; - } } - assert(OS.tell() - Start == F.getFileSize()); + assert(OW->getStream().tell() - Start == FragmentSize); } -/// WriteFileData - Write the \arg SD data to the output file. -static void WriteFileData(raw_ostream &OS, const MCSectionData &SD, - MachObjectWriter &MOW) { +void MCAssembler::WriteSectionData(const MCSectionData *SD, + const MCAsmLayout &Layout, + MCObjectWriter *OW) const { // Ignore virtual sections. - if (isVirtualSection(SD.getSection())) { - assert(SD.getFileSize() == 0); + if (getBackend().isVirtualSection(SD->getSection())) { + assert(Layout.getSectionFileSize(SD) == 0 && "Invalid size for section!"); + + // Check that contents are only things legal inside a virtual section. + for (MCSectionData::const_iterator it = SD->begin(), + ie = SD->end(); it != ie; ++it) { + switch (it->getKind()) { + default: + assert(0 && "Invalid fragment in virtual section!"); + case MCFragment::FT_Align: + assert(!cast(it)->getValueSize() && + "Invalid align in virtual section!"); + break; + case MCFragment::FT_Fill: + assert(!cast(it)->getValueSize() && + "Invalid fill in virtual section!"); + break; + } + } + return; } - uint64_t Start = OS.tell(); + uint64_t Start = OW->getStream().tell(); (void) Start; - for (MCSectionData::const_iterator it = SD.begin(), - ie = SD.end(); it != ie; ++it) - WriteFileData(OS, *it, MOW); - - // Add section padding. - assert(SD.getFileSize() >= SD.getSize() && "Invalid section sizes!"); - MOW.WriteZeros(SD.getFileSize() - SD.getSize()); + for (MCSectionData::const_iterator it = SD->begin(), + ie = SD->end(); it != ie; ++it) + WriteFragmentData(*this, Layout, *it, OW); - assert(OS.tell() - Start == SD.getFileSize()); + assert(OW->getStream().tell() - Start == Layout.getSectionFileSize(SD)); } void MCAssembler::Finish() { @@ -1307,31 +652,117 @@ void MCAssembler::Finish() { llvm::errs() << "assembler backend - pre-layout\n--\n"; dump(); }); + // Create the layout object. + MCAsmLayout Layout(*this); + + // Insert additional align fragments for concrete sections to explicitly pad + // the previous section to match their alignment requirements. This is for + // 'gas' compatibility, it shouldn't strictly be necessary. + // + // FIXME: This may be Mach-O specific. + for (unsigned i = 1, e = Layout.getSectionOrder().size(); i < e; ++i) { + MCSectionData *SD = Layout.getSectionOrder()[i]; + + // Ignore sections without alignment requirements. + unsigned Align = SD->getAlignment(); + if (Align <= 1) + continue; + + // Ignore virtual sections, they don't cause file size modifications. + if (getBackend().isVirtualSection(SD->getSection())) + continue; + + // Otherwise, create a new align fragment at the end of the previous + // section. + MCAlignFragment *AF = new MCAlignFragment(Align, 0, 1, Align, + Layout.getSectionOrder()[i - 1]); + AF->setOnlyAlignAddress(true); + } + + // Create dummy fragments and assign section ordinals. + unsigned SectionIndex = 0; + for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) { + // Create dummy fragments to eliminate any empty sections, this simplifies + // layout. + if (it->getFragmentList().empty()) + new MCFillFragment(0, 1, 0, it); + + it->setOrdinal(SectionIndex++); + } + + // Assign layout order indices to sections and fragments. + unsigned FragmentIndex = 0; + for (unsigned i = 0, e = Layout.getSectionOrder().size(); i != e; ++i) { + MCSectionData *SD = Layout.getSectionOrder()[i]; + SD->setLayoutOrder(i); + + for (MCSectionData::iterator it2 = SD->begin(), + ie2 = SD->end(); it2 != ie2; ++it2) + it2->setLayoutOrder(FragmentIndex++); + } + // Layout until everything fits. - while (LayoutOnce()) + while (LayoutOnce(Layout)) continue; DEBUG_WITH_TYPE("mc-dump", { - llvm::errs() << "assembler backend - post-layout\n--\n"; + llvm::errs() << "assembler backend - post-relaxation\n--\n"; + dump(); }); + + // Finalize the layout, including fragment lowering. + FinishLayout(Layout); + + DEBUG_WITH_TYPE("mc-dump", { + llvm::errs() << "assembler backend - final-layout\n--\n"; dump(); }); + uint64_t StartOffset = OS.tell(); + llvm::OwningPtr Writer(getBackend().createObjectWriter(OS)); + if (!Writer) + report_fatal_error("unable to create object writer!"); + + // Allow the object writer a chance to perform post-layout binding (for + // example, to set the index fields in the symbol data). + Writer->ExecutePostLayoutBinding(*this); + + // Evaluate and apply the fixups, generating relocation entries as necessary. + for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) { + for (MCSectionData::iterator it2 = it->begin(), + ie2 = it->end(); it2 != ie2; ++it2) { + MCDataFragment *DF = dyn_cast(it2); + if (!DF) + continue; + + for (MCDataFragment::fixup_iterator it3 = DF->fixup_begin(), + ie3 = DF->fixup_end(); it3 != ie3; ++it3) { + MCFixup &Fixup = *it3; + + // Evaluate the fixup. + MCValue Target; + uint64_t FixedValue; + if (!EvaluateFixup(Layout, Fixup, DF, Target, FixedValue)) { + // The fixup was unresolved, we need a relocation. Inform the object + // writer of the relocation, and give it an opportunity to adjust the + // fixup value if need be. + Writer->RecordRelocation(*this, Layout, DF, Fixup, Target,FixedValue); + } + + getBackend().ApplyFixup(Fixup, *DF, FixedValue); + } + } + } + // Write the object file. - // - // FIXME: Factor out MCObjectWriter. - bool Is64Bit = StringRef(getBackend().getTarget().getName()) == "x86-64"; - MachObjectWriter MOW(OS, Is64Bit); - MOW.WriteObject(*this); + Writer->WriteObject(*this, Layout); - OS.flush(); + stats::ObjectBytes += OS.tell() - StartOffset; } -bool MCAssembler::FixupNeedsRelaxation(MCAsmFixup &Fixup, MCDataFragment *DF) { - // FIXME: Share layout object. - MCAsmLayout Layout(*this); - - // Currently we only need to relax X86::reloc_pcrel_1byte. - if (unsigned(Fixup.Kind) != X86::reloc_pcrel_1byte) - return false; +bool MCAssembler::FixupNeedsRelaxation(const MCFixup &Fixup, + const MCFragment *DF, + const MCAsmLayout &Layout) const { + if (getRelaxAll()) + return true; // If we cannot resolve the fixup value, it requires relaxation. MCValue Target; @@ -1340,147 +771,132 @@ bool MCAssembler::FixupNeedsRelaxation(MCAsmFixup &Fixup, MCDataFragment *DF) { return true; // Otherwise, relax if the value is too big for a (signed) i8. + // + // FIXME: This is target dependent! return int64_t(Value) != int64_t(int8_t(Value)); } -bool MCAssembler::LayoutOnce() { - // Layout the concrete sections and fragments. - uint64_t Address = 0; - MCSectionData *Prev = 0; - for (iterator it = begin(), ie = end(); it != ie; ++it) { - MCSectionData &SD = *it; +bool MCAssembler::FragmentNeedsRelaxation(const MCInstFragment *IF, + const MCAsmLayout &Layout) const { + // If this inst doesn't ever need relaxation, ignore it. This occurs when we + // are intentionally pushing out inst fragments, or because we relaxed a + // previous instruction to one that doesn't need relaxation. + if (!getBackend().MayNeedRelaxation(IF->getInst())) + return false; - // Skip virtual sections. - if (isVirtualSection(SD.getSection())) - continue; + for (MCInstFragment::const_fixup_iterator it = IF->fixup_begin(), + ie = IF->fixup_end(); it != ie; ++it) + if (FixupNeedsRelaxation(*it, IF, Layout)) + return true; - // Align this section if necessary by adding padding bytes to the previous - // section. - if (uint64_t Pad = OffsetToAlignment(Address, it->getAlignment())) { - assert(Prev && "Missing prev section!"); - Prev->setFileSize(Prev->getFileSize() + Pad); - Address += Pad; - } + return false; +} - // Layout the section fragments and its size. - SD.setAddress(Address); - LayoutSection(SD); - Address += SD.getFileSize(); +bool MCAssembler::LayoutOnce(MCAsmLayout &Layout) { + ++stats::RelaxationSteps; - Prev = &SD; - } + // Layout the sections in order. + Layout.LayoutFile(); - // Layout the virtual sections. + // Scan for fragments that need relaxation. + bool WasRelaxed = false; for (iterator it = begin(), ie = end(); it != ie; ++it) { MCSectionData &SD = *it; - if (!isVirtualSection(SD.getSection())) - continue; + for (MCSectionData::iterator it2 = SD.begin(), + ie2 = SD.end(); it2 != ie2; ++it2) { + // Check if this is an instruction fragment that needs relaxation. + MCInstFragment *IF = dyn_cast(it2); + if (!IF || !FragmentNeedsRelaxation(IF, Layout)) + continue; - // Align this section if necessary by adding padding bytes to the previous - // section. - if (uint64_t Pad = OffsetToAlignment(Address, it->getAlignment())) - Address += Pad; + ++stats::RelaxedInstructions; - SD.setAddress(Address); - LayoutSection(SD); - Address += SD.getSize(); + // FIXME-PERF: We could immediately lower out instructions if we can tell + // they are fully resolved, to avoid retesting on later passes. + + // Relax the fragment. + + MCInst Relaxed; + getBackend().RelaxInstruction(IF->getInst(), Relaxed); + + // Encode the new instruction. + // + // FIXME-PERF: If it matters, we could let the target do this. It can + // probably do so more efficiently in many cases. + SmallVector Fixups; + SmallString<256> Code; + raw_svector_ostream VecOS(Code); + getEmitter().EncodeInstruction(Relaxed, VecOS, Fixups); + VecOS.flush(); + + // Update the instruction fragment. + int SlideAmount = Code.size() - IF->getInstSize(); + IF->setInst(Relaxed); + IF->getCode() = Code; + IF->getFixups().clear(); + // FIXME: Eliminate copy. + for (unsigned i = 0, e = Fixups.size(); i != e; ++i) + IF->getFixups().push_back(Fixups[i]); + + // Update the layout, and remember that we relaxed. + Layout.UpdateForSlide(IF, SlideAmount); + WasRelaxed = true; + } } - // Scan the fixups in order and relax any that don't fit. + return WasRelaxed; +} + +void MCAssembler::FinishLayout(MCAsmLayout &Layout) { + // Lower out any instruction fragments, to simplify the fixup application and + // output. + // + // FIXME-PERF: We don't have to do this, but the assumption is that it is + // cheap (we will mostly end up eliminating fragments and appending on to data + // fragments), so the extra complexity downstream isn't worth it. Evaluate + // this assumption. for (iterator it = begin(), ie = end(); it != ie; ++it) { MCSectionData &SD = *it; for (MCSectionData::iterator it2 = SD.begin(), ie2 = SD.end(); it2 != ie2; ++it2) { - MCDataFragment *DF = dyn_cast(it2); - if (!DF) + MCInstFragment *IF = dyn_cast(it2); + if (!IF) continue; - for (MCDataFragment::fixup_iterator it3 = DF->fixup_begin(), - ie3 = DF->fixup_end(); it3 != ie3; ++it3) { - MCAsmFixup &Fixup = *it3; - - // Check whether we need to relax this fixup. - if (!FixupNeedsRelaxation(Fixup, DF)) - continue; - - // Relax the instruction. - // - // FIXME: This is a huge temporary hack which just looks for x86 - // branches; the only thing we need to relax on x86 is - // 'X86::reloc_pcrel_1byte'. Once we have MCInst fragments, this will be - // replaced by a TargetAsmBackend hook (most likely tblgen'd) to relax - // an individual MCInst. - SmallVectorImpl &C = DF->getContents(); - uint64_t PrevOffset = Fixup.Offset; - unsigned Amt = 0; - - // jcc instructions - if (unsigned(C[Fixup.Offset-1]) >= 0x70 && - unsigned(C[Fixup.Offset-1]) <= 0x7f) { - C[Fixup.Offset] = C[Fixup.Offset-1] + 0x10; - C[Fixup.Offset-1] = char(0x0f); - ++Fixup.Offset; - Amt = 4; - - // jmp rel8 - } else if (C[Fixup.Offset-1] == char(0xeb)) { - C[Fixup.Offset-1] = char(0xe9); - Amt = 3; - - } else - llvm_unreachable("unknown 1 byte pcrel instruction!"); - - Fixup.Value = MCBinaryExpr::Create( - MCBinaryExpr::Sub, Fixup.Value, - MCConstantExpr::Create(3, getContext()), - getContext()); - C.insert(C.begin() + Fixup.Offset, Amt, char(0)); - Fixup.Kind = MCFixupKind(X86::reloc_pcrel_4byte); - - // Update the remaining fixups, which have slid. - // - // FIXME: This is bad for performance, but will be eliminated by the - // move to MCInst specific fragments. - ++it3; - for (; it3 != ie3; ++it3) - it3->Offset += Amt; - - // Update all the symbols for this fragment, which may have slid. - // - // FIXME: This is really really bad for performance, but will be - // eliminated by the move to MCInst specific fragments. - for (MCAssembler::symbol_iterator it = symbol_begin(), - ie = symbol_end(); it != ie; ++it) { - MCSymbolData &SD = *it; - - if (it->getFragment() != DF) - continue; - - if (SD.getOffset() > PrevOffset) - SD.setOffset(SD.getOffset() + Amt); - } - - // Restart layout. - // - // FIXME: This is O(N^2), but will be eliminated once we have a smart - // MCAsmLayout object. - return true; - } + // Create a new data fragment for the instruction. + // + // FIXME-PERF: Reuse previous data fragment if possible. + MCDataFragment *DF = new MCDataFragment(); + SD.getFragmentList().insert(it2, DF); + + // Update the data fragments layout data. + DF->setParent(IF->getParent()); + DF->setAtom(IF->getAtom()); + DF->setLayoutOrder(IF->getLayoutOrder()); + Layout.FragmentReplaced(IF, DF); + + // Copy in the data and the fixups. + DF->getContents().append(IF->getCode().begin(), IF->getCode().end()); + for (unsigned i = 0, e = IF->getFixups().size(); i != e; ++i) + DF->getFixups().push_back(IF->getFixups()[i]); + + // Delete the instruction fragment and update the iterator. + SD.getFragmentList().erase(IF); + it2 = DF; } } - - return false; } // Debugging methods namespace llvm { -raw_ostream &operator<<(raw_ostream &OS, const MCAsmFixup &AF) { - OS << ""; +raw_ostream &operator<<(raw_ostream &OS, const MCFixup &AF) { + OS << ""; return OS; } @@ -1489,83 +905,82 @@ raw_ostream &operator<<(raw_ostream &OS, const MCAsmFixup &AF) { void MCFragment::dump() { raw_ostream &OS = llvm::errs(); - OS << ""; -} - -void MCAlignFragment::dump() { - raw_ostream &OS = llvm::errs(); - - OS << "MCFragment::dump(); - OS << "\n "; - OS << " Alignment:" << getAlignment() - << " Value:" << getValue() << " ValueSize:" << getValueSize() - << " MaxBytesToEmit:" << getMaxBytesToEmit() << ">"; -} + OS << "<"; + switch (getKind()) { + case MCFragment::FT_Align: OS << "MCAlignFragment"; break; + case MCFragment::FT_Data: OS << "MCDataFragment"; break; + case MCFragment::FT_Fill: OS << "MCFillFragment"; break; + case MCFragment::FT_Inst: OS << "MCInstFragment"; break; + case MCFragment::FT_Org: OS << "MCOrgFragment"; break; + } -void MCDataFragment::dump() { - raw_ostream &OS = llvm::errs(); + OS << ""; - OS << "MCFragment::dump(); - OS << "\n "; - OS << " Contents:["; - for (unsigned i = 0, e = getContents().size(); i != e; ++i) { - if (i) OS << ","; - OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF); + switch (getKind()) { + case MCFragment::FT_Align: { + const MCAlignFragment *AF = cast(this); + if (AF->hasEmitNops()) + OS << " (emit nops)"; + if (AF->hasOnlyAlignAddress()) + OS << " (only align section)"; + OS << "\n "; + OS << " Alignment:" << AF->getAlignment() + << " Value:" << AF->getValue() << " ValueSize:" << AF->getValueSize() + << " MaxBytesToEmit:" << AF->getMaxBytesToEmit() << ">"; + break; } - OS << "] (" << getContents().size() << " bytes)"; - - if (!getFixups().empty()) { - OS << ",\n "; - OS << " Fixups:["; - for (fixup_iterator it = fixup_begin(), ie = fixup_end(); it != ie; ++it) { - if (it != fixup_begin()) OS << ",\n "; - OS << *it; + case MCFragment::FT_Data: { + const MCDataFragment *DF = cast(this); + OS << "\n "; + OS << " Contents:["; + const SmallVectorImpl &Contents = DF->getContents(); + for (unsigned i = 0, e = Contents.size(); i != e; ++i) { + if (i) OS << ","; + OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF); + } + OS << "] (" << Contents.size() << " bytes)"; + + if (!DF->getFixups().empty()) { + OS << ",\n "; + OS << " Fixups:["; + for (MCDataFragment::const_fixup_iterator it = DF->fixup_begin(), + ie = DF->fixup_end(); it != ie; ++it) { + if (it != DF->fixup_begin()) OS << ",\n "; + OS << *it; + } + OS << "]"; } - OS << "]"; + break; + } + case MCFragment::FT_Fill: { + const MCFillFragment *FF = cast(this); + OS << " Value:" << FF->getValue() << " ValueSize:" << FF->getValueSize() + << " Size:" << FF->getSize(); + break; + } + case MCFragment::FT_Inst: { + const MCInstFragment *IF = cast(this); + OS << "\n "; + OS << " Inst:"; + IF->getInst().dump_pretty(OS); + break; + } + case MCFragment::FT_Org: { + const MCOrgFragment *OF = cast(this); + OS << "\n "; + OS << " Offset:" << OF->getOffset() << " Value:" << OF->getValue(); + break; + } } - OS << ">"; } -void MCFillFragment::dump() { - raw_ostream &OS = llvm::errs(); - - OS << "MCFragment::dump(); - OS << "\n "; - OS << " Value:" << getValue() << " ValueSize:" << getValueSize() - << " Count:" << getCount() << ">"; -} - -void MCOrgFragment::dump() { - raw_ostream &OS = llvm::errs(); - - OS << "MCFragment::dump(); - OS << "\n "; - OS << " Offset:" << getOffset() << " Value:" << getValue() << ">"; -} - -void MCZeroFillFragment::dump() { - raw_ostream &OS = llvm::errs(); - - OS << "MCFragment::dump(); - OS << "\n "; - OS << " Size:" << getSize() << " Alignment:" << getAlignment() << ">"; -} - void MCSectionData::dump() { raw_ostream &OS = llvm::errs(); OS << "