X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FMC%2FMCMachOStreamer.cpp;h=d5c7101d0d554da05fca859546c323b67d6a3fdc;hp=b152a8c85e24eb4ad58fbc070afff20e20136b42;hb=e93f977e8d84407de9aec402473487737ad1339b;hpb=b4316028b3978e65cc2b97042292637857dfad49 diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp index b152a8c85e2..d5c7101d0d5 100644 --- a/lib/MC/MCMachOStreamer.cpp +++ b/lib/MC/MCMachOStreamer.cpp @@ -1,3 +1,4 @@ +//===-- MCMachOStreamer.cpp - MachO Streamer ------------------------------===// // // The LLVM Compiler Infrastructure // @@ -7,21 +8,25 @@ //===----------------------------------------------------------------------===// #include "llvm/MC/MCStreamer.h" - +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/MC/MCAsmBackend.h" #include "llvm/MC/MCAssembler.h" -#include "llvm/MC/MCContext.h" #include "llvm/MC/MCCodeEmitter.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCDwarf.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCInst.h" +#include "llvm/MC/MCLinkerOptimizationHint.h" +#include "llvm/MC/MCMachOSymbolFlags.h" +#include "llvm/MC/MCObjectFileInfo.h" #include "llvm/MC/MCObjectStreamer.h" #include "llvm/MC/MCSection.h" -#include "llvm/MC/MCSymbol.h" -#include "llvm/MC/MCMachOSymbolFlags.h" #include "llvm/MC/MCSectionMachO.h" -#include "llvm/MC/MCDwarf.h" -#include "llvm/MC/MCAsmBackend.h" +#include "llvm/MC/MCSymbol.h" #include "llvm/Support/Dwarf.h" #include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/TargetRegistry.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; @@ -30,77 +35,138 @@ namespace { class MCMachOStreamer : public MCObjectStreamer { private: - virtual void EmitInstToData(const MCInst &Inst); + /// LabelSections - true if each section change should emit a linker local + /// label for use in relocations for assembler local references. Obviates the + /// need for local relocations. False by default. + bool LabelSections; + + bool DWARFMustBeAtTheEnd; + bool CreatedADWARFSection; + + /// HasSectionLabel - map of which sections have already had a non-local + /// label emitted to them. Used so we don't emit extraneous linker local + /// labels in the middle of the section. + DenseMap HasSectionLabel; + + void EmitInstToData(const MCInst &Inst, const MCSubtargetInfo &STI) override; void EmitDataRegion(DataRegionData::KindTy Kind); void EmitDataRegionEnd(); + public: - MCMachOStreamer(MCContext &Context, MCAsmBackend &MAB, - raw_ostream &OS, MCCodeEmitter *Emitter) - : MCObjectStreamer(Context, MAB, OS, Emitter) {} + MCMachOStreamer(MCContext &Context, MCAsmBackend &MAB, raw_ostream &OS, + MCCodeEmitter *Emitter, bool DWARFMustBeAtTheEnd, bool label) + : MCObjectStreamer(Context, MAB, OS, Emitter), LabelSections(label), + DWARFMustBeAtTheEnd(DWARFMustBeAtTheEnd), CreatedADWARFSection(false) {} + + /// state management + void reset() override { + HasSectionLabel.clear(); + MCObjectStreamer::reset(); + } /// @name MCStreamer Interface /// @{ - virtual void InitSections(); - virtual void EmitLabel(MCSymbol *Symbol); - virtual void EmitEHSymAttributes(const MCSymbol *Symbol, - MCSymbol *EHSymbol); - virtual void EmitAssemblerFlag(MCAssemblerFlag Flag); - virtual void EmitDataRegion(MCDataRegionType Kind); - virtual void EmitThumbFunc(MCSymbol *Func); - virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value); - virtual void EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute); - virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue); - virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, - unsigned ByteAlignment); - virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol) { + void ChangeSection(const MCSection *Sect, const MCExpr *Subsect) override; + void EmitLabel(MCSymbol *Symbol) override; + void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol) override; + void EmitAssemblerFlag(MCAssemblerFlag Flag) override; + void EmitLinkerOptions(ArrayRef Options) override; + void EmitDataRegion(MCDataRegionType Kind) override; + void EmitVersionMin(MCVersionMinType Kind, unsigned Major, + unsigned Minor, unsigned Update) override; + void EmitThumbFunc(MCSymbol *Func) override; + bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override; + void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override; + void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, + unsigned ByteAlignment) override; + void BeginCOFFSymbolDef(const MCSymbol *Symbol) override { llvm_unreachable("macho doesn't support this directive"); } - virtual void EmitCOFFSymbolStorageClass(int StorageClass) { + void EmitCOFFSymbolStorageClass(int StorageClass) override { llvm_unreachable("macho doesn't support this directive"); } - virtual void EmitCOFFSymbolType(int Type) { + void EmitCOFFSymbolType(int Type) override { llvm_unreachable("macho doesn't support this directive"); } - virtual void EndCOFFSymbolDef() { + void EndCOFFSymbolDef() override { llvm_unreachable("macho doesn't support this directive"); } - virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) { + void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) override { llvm_unreachable("macho doesn't support this directive"); } - virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size, - unsigned ByteAlignment); - virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0, - uint64_t Size = 0, unsigned ByteAlignment = 0); - virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol, - uint64_t Size, unsigned ByteAlignment = 0); - virtual void EmitBytes(StringRef Data, unsigned AddrSpace); - virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0, - unsigned ValueSize = 1, - unsigned MaxBytesToEmit = 0); - virtual void EmitCodeAlignment(unsigned ByteAlignment, - unsigned MaxBytesToEmit = 0); - - virtual void EmitFileDirective(StringRef Filename) { + void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size, + unsigned ByteAlignment) override; + void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = nullptr, + uint64_t Size = 0, unsigned ByteAlignment = 0) override; + void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol, uint64_t Size, + unsigned ByteAlignment = 0) override; + + void EmitFileDirective(StringRef Filename) override { // FIXME: Just ignore the .file; it isn't important enough to fail the // entire assembly. - //report_fatal_error("unsupported directive: '.file'"); + // report_fatal_error("unsupported directive: '.file'"); } - virtual void FinishImpl(); + void EmitIdent(StringRef IdentString) override { + llvm_unreachable("macho doesn't support this directive"); + } - /// @} + void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) override { + getAssembler().getLOHContainer().addDirective(Kind, Args); + } + + void FinishImpl() override; }; } // end anonymous namespace. -void MCMachOStreamer::InitSections() { - SwitchSection(getContext().getMachOSection("__TEXT", "__text", - MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS, - 0, SectionKind::getText())); +static bool canGoAfterDWARF(const MCSectionMachO &MSec) { + // These sections are created by the assembler itself after the end of + // the .s file. + StringRef SegName = MSec.getSegmentName(); + StringRef SecName = MSec.getSectionName(); + + if (SegName == "__LD" && SecName == "__compact_unwind") + return true; + + if (SegName == "__IMPORT") { + if (SecName == "__jump_table") + return true; + + if (SecName == "__pointers") + return true; + } + + if (SegName == "__TEXT" && SecName == "__eh_frame") + return true; + + if (SegName == "__DATA" && SecName == "__nl_symbol_ptr") + return true; + return false; +} + +void MCMachOStreamer::ChangeSection(const MCSection *Section, + const MCExpr *Subsection) { + // Change the section normally. + bool Created = MCObjectStreamer::changeSectionImpl(Section, Subsection); + const MCSectionMachO &MSec = *cast(Section); + StringRef SegName = MSec.getSegmentName(); + if (SegName == "__DWARF") + CreatedADWARFSection = true; + else if (Created && DWARFMustBeAtTheEnd && !canGoAfterDWARF(MSec)) + assert(!CreatedADWARFSection && "Creating regular section after DWARF"); + + // Output a linker-local symbol so we don't need section-relative local + // relocations. The linker hates us when we do that. + if (LabelSections && !HasSectionLabel[Section]) { + MCSymbol *Label = getContext().CreateLinkerPrivateTempSymbol(); + EmitLabel(Label); + HasSectionLabel[Section] = true; + } } void MCMachOStreamer::EmitEHSymAttributes(const MCSymbol *Symbol, @@ -119,11 +185,11 @@ void MCMachOStreamer::EmitLabel(MCSymbol *Symbol) { assert(Symbol->isUndefined() && "Cannot define a symbol twice!"); // isSymbolLinkerVisible uses the section. - Symbol->setSection(*getCurrentSection()); + AssignSection(Symbol, getCurrentSection().first); // We have to create a new fragment if this is an atom defining symbol, // fragments cannot span atoms. if (getAssembler().isSymbolLinkerVisible(*Symbol)) - new MCDataFragment(getCurrentSectionData()); + insert(new MCDataFragment()); MCObjectStreamer::EmitLabel(Symbol); @@ -145,7 +211,7 @@ void MCMachOStreamer::EmitDataRegion(DataRegionData::KindTy Kind) { MCSymbol *Start = getContext().CreateTempSymbol(); EmitLabel(Start); // Record the region for the object writer to use. - DataRegionData Data = { Kind, Start, NULL }; + DataRegionData Data = { Kind, Start, nullptr }; std::vector &Regions = getAssembler().getDataRegions(); Regions.push_back(Data); } @@ -154,9 +220,9 @@ void MCMachOStreamer::EmitDataRegionEnd() { if (!getAssembler().getBackend().hasDataInCodeSupport()) return; std::vector &Regions = getAssembler().getDataRegions(); - assert(Regions.size() && "Mismatched .end_data_region!"); + assert(!Regions.empty() && "Mismatched .end_data_region!"); DataRegionData &Data = Regions.back(); - assert(Data.End == NULL && "Mismatched .end_data_region!"); + assert(!Data.End && "Mismatched .end_data_region!"); // Create a temporary label to mark the end of the data region. Data.End = getContext().CreateTempSymbol(); EmitLabel(Data.End); @@ -177,6 +243,10 @@ void MCMachOStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) { } } +void MCMachOStreamer::EmitLinkerOptions(ArrayRef Options) { + getAssembler().getLinkerOptions().push_back(Options); +} + void MCMachOStreamer::EmitDataRegion(MCDataRegionType Kind) { switch (Kind) { case MCDR_DataRegion: @@ -197,25 +267,18 @@ void MCMachOStreamer::EmitDataRegion(MCDataRegionType Kind) { } } +void MCMachOStreamer::EmitVersionMin(MCVersionMinType Kind, unsigned Major, + unsigned Minor, unsigned Update) { + getAssembler().setVersionMinInfo(Kind, Major, Minor, Update); +} + void MCMachOStreamer::EmitThumbFunc(MCSymbol *Symbol) { // Remember that the function is a thumb function. Fixup and relocation // values will need adjusted. getAssembler().setIsThumbFunc(Symbol); - - // Mark the thumb bit on the symbol. - MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol); - SD.setFlags(SD.getFlags() | SF_ThumbFunc); } -void MCMachOStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) { - // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into - // MCObjectStreamer. - // FIXME: Lift context changes into super class. - getAssembler().getOrCreateSymbolData(*Symbol); - Symbol->setVariableValue(AddValueSymbols(Value)); -} - -void MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Symbol, +bool MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) { // Indirect symbols are handled differently, to match how 'as' handles // them. This makes writing matching .o files easier. @@ -226,7 +289,7 @@ void MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Symbol, ISD.Symbol = Symbol; ISD.SectionData = getCurrentSectionData(); getAssembler().getIndirectSymbols().push_back(ISD); - return; + return true; } // Adding a symbol attribute always introduces the symbol, note that an @@ -255,7 +318,7 @@ void MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Symbol, case MCSA_Protected: case MCSA_Weak: case MCSA_Local: - llvm_unreachable("Invalid symbol attribute for Mach-O!"); + return false; case MCSA_Global: SD.setExternal(true); @@ -307,6 +370,8 @@ void MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Symbol, SD.setFlags(SD.getFlags() | SF_WeakDefinition | SF_WeakReference); break; } + + return true; } void MCMachOStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) { @@ -322,6 +387,8 @@ void MCMachOStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, // FIXME: Darwin 'as' does appear to allow redef of a .comm by itself. assert(Symbol->isUndefined() && "Cannot define a symbol twice!"); + AssignSection(Symbol, nullptr); + MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol); SD.setExternal(true); SD.setCommon(Size, ByteAlignment); @@ -330,9 +397,7 @@ void MCMachOStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, void MCMachOStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment) { // '.lcomm' is equivalent to '.zerofill'. - return EmitZerofill(getContext().getMachOSection("__DATA", "__bss", - MCSectionMachO::S_ZEROFILL, - 0, SectionKind::getBSS()), + return EmitZerofill(getContext().getObjectFileInfo()->getDataBSSSection(), Symbol, Size, ByteAlignment); } @@ -344,7 +409,8 @@ void MCMachOStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol, if (!Symbol) return; - // FIXME: Assert that this section has the zerofill type. + // On darwin all virtual sections have zerofill type. + assert(Section->isVirtualSection() && "Section does not have zerofill type!"); assert(Symbol->isUndefined() && "Cannot define a symbol twice!"); @@ -357,7 +423,7 @@ void MCMachOStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol, MCFragment *F = new MCFillFragment(0, 0, Size, &SectData); SD.setFragment(F); - Symbol->setSection(*Section); + AssignSection(Symbol, Section); // Update the maximum alignment on the zero fill section if necessary. if (ByteAlignment > SectData.getAlignment()) @@ -372,61 +438,26 @@ void MCMachOStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol, return; } -void MCMachOStreamer::EmitBytes(StringRef Data, unsigned AddrSpace) { - // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into - // MCObjectStreamer. - getOrCreateDataFragment()->getContents().append(Data.begin(), Data.end()); -} - -void MCMachOStreamer::EmitValueToAlignment(unsigned ByteAlignment, - int64_t Value, unsigned ValueSize, - unsigned MaxBytesToEmit) { - // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into - // MCObjectStreamer. - if (MaxBytesToEmit == 0) - MaxBytesToEmit = ByteAlignment; - new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit, - getCurrentSectionData()); - - // Update the maximum alignment on the current section if necessary. - if (ByteAlignment > getCurrentSectionData()->getAlignment()) - getCurrentSectionData()->setAlignment(ByteAlignment); -} - -void MCMachOStreamer::EmitCodeAlignment(unsigned ByteAlignment, - unsigned MaxBytesToEmit) { - // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into - // MCObjectStreamer. - if (MaxBytesToEmit == 0) - MaxBytesToEmit = ByteAlignment; - MCAlignFragment *F = new MCAlignFragment(ByteAlignment, 0, 1, MaxBytesToEmit, - getCurrentSectionData()); - F->setEmitNops(true); - - // Update the maximum alignment on the current section if necessary. - if (ByteAlignment > getCurrentSectionData()->getAlignment()) - getCurrentSectionData()->setAlignment(ByteAlignment); -} - -void MCMachOStreamer::EmitInstToData(const MCInst &Inst) { +void MCMachOStreamer::EmitInstToData(const MCInst &Inst, + const MCSubtargetInfo &STI) { MCDataFragment *DF = getOrCreateDataFragment(); SmallVector Fixups; SmallString<256> Code; raw_svector_ostream VecOS(Code); - getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, Fixups); + getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, Fixups, STI); VecOS.flush(); // Add the fixups and data. for (unsigned i = 0, e = Fixups.size(); i != e; ++i) { Fixups[i].setOffset(Fixups[i].getOffset() + DF->getContents().size()); - DF->addFixup(Fixups[i]); + DF->getFixups().push_back(Fixups[i]); } DF->getContents().append(Code.begin(), Code.end()); } void MCMachOStreamer::FinishImpl() { - EmitFrames(true); + EmitFrames(&getAssembler().getBackend()); // We have to set the fragment atom associations so we can relax properly for // Mach-O. @@ -434,13 +465,12 @@ void MCMachOStreamer::FinishImpl() { // First, scan the symbol table to build a lookup table from fragments to // defining symbols. DenseMap DefiningSymbolMap; - for (MCAssembler::symbol_iterator it = getAssembler().symbol_begin(), - ie = getAssembler().symbol_end(); it != ie; ++it) { - if (getAssembler().isSymbolLinkerVisible(it->getSymbol()) && - it->getFragment()) { + for (MCSymbolData &SD : getAssembler().symbols()) { + if (getAssembler().isSymbolLinkerVisible(SD.getSymbol()) && + SD.getFragment()) { // An atom defining symbol should never be internal to a fragment. - assert(it->getOffset() == 0 && "Invalid offset in atom defining symbol!"); - DefiningSymbolMap[it->getFragment()] = it; + assert(SD.getOffset() == 0 && "Invalid offset in atom defining symbol!"); + DefiningSymbolMap[SD.getFragment()] = &SD; } } @@ -448,7 +478,7 @@ void MCMachOStreamer::FinishImpl() { // symbol. for (MCAssembler::iterator it = getAssembler().begin(), ie = getAssembler().end(); it != ie; ++it) { - MCSymbolData *CurrentAtom = 0; + MCSymbolData *CurrentAtom = nullptr; for (MCSectionData::iterator it2 = it->begin(), ie2 = it->end(); it2 != ie2; ++it2) { if (MCSymbolData *SD = DefiningSymbolMap.lookup(it2)) @@ -462,8 +492,10 @@ void MCMachOStreamer::FinishImpl() { MCStreamer *llvm::createMachOStreamer(MCContext &Context, MCAsmBackend &MAB, raw_ostream &OS, MCCodeEmitter *CE, - bool RelaxAll) { - MCMachOStreamer *S = new MCMachOStreamer(Context, MAB, OS, CE); + bool RelaxAll, bool DWARFMustBeAtTheEnd, + bool LabelSections) { + MCMachOStreamer *S = new MCMachOStreamer(Context, MAB, OS, CE, + DWARFMustBeAtTheEnd, LabelSections); if (RelaxAll) S->getAssembler().setRelaxAll(true); return S;