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diff --git a/contrib/llvm/lib/MC/MCMachOStreamer.cpp b/contrib/llvm/lib/MC/MCMachOStreamer.cpp
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+//===-- MCMachOStreamer.cpp - MachO Streamer ------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#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/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/MCObjectFileInfo.h"
+#include "llvm/MC/MCObjectStreamer.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCSectionMachO.h"
+#include "llvm/MC/MCSymbolMachO.h"
+#include "llvm/MC/MCValue.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;
+
+namespace {
+
+class MCMachOStreamer : public MCObjectStreamer {
+private:
+ /// 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<const MCSection*, bool> HasSectionLabel;
+
+ void EmitInstToData(const MCInst &Inst, const MCSubtargetInfo &STI) override;
+
+ void EmitDataRegion(DataRegionData::KindTy Kind);
+ void EmitDataRegionEnd();
+
+public:
+ MCMachOStreamer(MCContext &Context, MCAsmBackend &MAB, raw_pwrite_stream &OS,
+ MCCodeEmitter *Emitter, bool DWARFMustBeAtTheEnd, bool label)
+ : MCObjectStreamer(Context, MAB, OS, Emitter), LabelSections(label),
+ DWARFMustBeAtTheEnd(DWARFMustBeAtTheEnd), CreatedADWARFSection(false) {}
+
+ /// state management
+ void reset() override {
+ CreatedADWARFSection = false;
+ HasSectionLabel.clear();
+ MCObjectStreamer::reset();
+ }
+
+ /// @name MCStreamer Interface
+ /// @{
+
+ void ChangeSection(MCSection *Sect, const MCExpr *Subsect) override;
+ void EmitLabel(MCSymbol *Symbol) override;
+ void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override;
+ void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol) override;
+ void EmitAssemblerFlag(MCAssemblerFlag Flag) override;
+ void EmitLinkerOptions(ArrayRef<std::string> 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");
+ }
+ void EmitCOFFSymbolStorageClass(int StorageClass) override {
+ llvm_unreachable("macho doesn't support this directive");
+ }
+ void EmitCOFFSymbolType(int Type) override {
+ llvm_unreachable("macho doesn't support this directive");
+ }
+ void EndCOFFSymbolDef() override {
+ llvm_unreachable("macho doesn't support this directive");
+ }
+ void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+ unsigned ByteAlignment) override;
+ void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
+ uint64_t Size = 0, unsigned ByteAlignment = 0) override;
+ void EmitTBSSSymbol(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'");
+ }
+
+ 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.
+
+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(MCSection *Section,
+ const MCExpr *Subsection) {
+ // Change the section normally.
+ bool Created = MCObjectStreamer::changeSectionImpl(Section, Subsection);
+ const MCSectionMachO &MSec = *cast<MCSectionMachO>(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] &&
+ !Section->getBeginSymbol()) {
+ MCSymbol *Label = getContext().createLinkerPrivateTempSymbol();
+ Section->setBeginSymbol(Label);
+ HasSectionLabel[Section] = true;
+ }
+}
+
+void MCMachOStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
+ MCSymbol *EHSymbol) {
+ getAssembler().registerSymbol(*Symbol);
+ if (Symbol->isExternal())
+ EmitSymbolAttribute(EHSymbol, MCSA_Global);
+ if (cast<MCSymbolMachO>(Symbol)->isWeakDefinition())
+ EmitSymbolAttribute(EHSymbol, MCSA_WeakDefinition);
+ if (Symbol->isPrivateExtern())
+ EmitSymbolAttribute(EHSymbol, MCSA_PrivateExtern);
+}
+
+void MCMachOStreamer::EmitLabel(MCSymbol *Symbol) {
+ assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
+
+ // We have to create a new fragment if this is an atom defining symbol,
+ // fragments cannot span atoms.
+ if (getAssembler().isSymbolLinkerVisible(*Symbol))
+ insert(new MCDataFragment());
+
+ MCObjectStreamer::EmitLabel(Symbol);
+
+ // This causes the reference type flag to be cleared. Darwin 'as' was "trying"
+ // to clear the weak reference and weak definition bits too, but the
+ // implementation was buggy. For now we just try to match 'as', for
+ // diffability.
+ //
+ // FIXME: Cleanup this code, these bits should be emitted based on semantic
+ // properties, not on the order of definition, etc.
+ cast<MCSymbolMachO>(Symbol)->clearReferenceType();
+}
+
+void MCMachOStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
+ MCValue Res;
+
+ if (Value->evaluateAsRelocatable(Res, nullptr, nullptr)) {
+ if (const MCSymbolRefExpr *SymAExpr = Res.getSymA()) {
+ const MCSymbol &SymA = SymAExpr->getSymbol();
+ if (!Res.getSymB() && (SymA.getName() == "" || Res.getConstant() != 0))
+ cast<MCSymbolMachO>(Symbol)->setAltEntry();
+ }
+ }
+ MCObjectStreamer::EmitAssignment(Symbol, Value);
+}
+
+void MCMachOStreamer::EmitDataRegion(DataRegionData::KindTy Kind) {
+ // Create a temporary label to mark the start of the data region.
+ MCSymbol *Start = getContext().createTempSymbol();
+ EmitLabel(Start);
+ // Record the region for the object writer to use.
+ DataRegionData Data = { Kind, Start, nullptr };
+ std::vector<DataRegionData> &Regions = getAssembler().getDataRegions();
+ Regions.push_back(Data);
+}
+
+void MCMachOStreamer::EmitDataRegionEnd() {
+ std::vector<DataRegionData> &Regions = getAssembler().getDataRegions();
+ assert(!Regions.empty() && "Mismatched .end_data_region!");
+ DataRegionData &Data = Regions.back();
+ 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);
+}
+
+void MCMachOStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
+ // Let the target do whatever target specific stuff it needs to do.
+ getAssembler().getBackend().handleAssemblerFlag(Flag);
+ // Do any generic stuff we need to do.
+ switch (Flag) {
+ case MCAF_SyntaxUnified: return; // no-op here.
+ case MCAF_Code16: return; // Change parsing mode; no-op here.
+ case MCAF_Code32: return; // Change parsing mode; no-op here.
+ case MCAF_Code64: return; // Change parsing mode; no-op here.
+ case MCAF_SubsectionsViaSymbols:
+ getAssembler().setSubsectionsViaSymbols(true);
+ return;
+ }
+}
+
+void MCMachOStreamer::EmitLinkerOptions(ArrayRef<std::string> Options) {
+ getAssembler().getLinkerOptions().push_back(Options);
+}
+
+void MCMachOStreamer::EmitDataRegion(MCDataRegionType Kind) {
+ switch (Kind) {
+ case MCDR_DataRegion:
+ EmitDataRegion(DataRegionData::Data);
+ return;
+ case MCDR_DataRegionJT8:
+ EmitDataRegion(DataRegionData::JumpTable8);
+ return;
+ case MCDR_DataRegionJT16:
+ EmitDataRegion(DataRegionData::JumpTable16);
+ return;
+ case MCDR_DataRegionJT32:
+ EmitDataRegion(DataRegionData::JumpTable32);
+ return;
+ case MCDR_DataRegionEnd:
+ EmitDataRegionEnd();
+ return;
+ }
+}
+
+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);
+ cast<MCSymbolMachO>(Symbol)->setThumbFunc();
+}
+
+bool MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Sym,
+ MCSymbolAttr Attribute) {
+ MCSymbolMachO *Symbol = cast<MCSymbolMachO>(Sym);
+
+ // Indirect symbols are handled differently, to match how 'as' handles
+ // them. This makes writing matching .o files easier.
+ if (Attribute == MCSA_IndirectSymbol) {
+ // Note that we intentionally cannot use the symbol data here; this is
+ // important for matching the string table that 'as' generates.
+ IndirectSymbolData ISD;
+ ISD.Symbol = Symbol;
+ ISD.Section = getCurrentSectionOnly();
+ getAssembler().getIndirectSymbols().push_back(ISD);
+ return true;
+ }
+
+ // Adding a symbol attribute always introduces the symbol, note that an
+ // important side effect of calling registerSymbol here is to register
+ // the symbol with the assembler.
+ getAssembler().registerSymbol(*Symbol);
+
+ // The implementation of symbol attributes is designed to match 'as', but it
+ // leaves much to desired. It doesn't really make sense to arbitrarily add and
+ // remove flags, but 'as' allows this (in particular, see .desc).
+ //
+ // In the future it might be worth trying to make these operations more well
+ // defined.
+ switch (Attribute) {
+ case MCSA_Invalid:
+ case MCSA_ELF_TypeFunction:
+ case MCSA_ELF_TypeIndFunction:
+ case MCSA_ELF_TypeObject:
+ case MCSA_ELF_TypeTLS:
+ case MCSA_ELF_TypeCommon:
+ case MCSA_ELF_TypeNoType:
+ case MCSA_ELF_TypeGnuUniqueObject:
+ case MCSA_Hidden:
+ case MCSA_IndirectSymbol:
+ case MCSA_Internal:
+ case MCSA_Protected:
+ case MCSA_Weak:
+ case MCSA_Local:
+ return false;
+
+ case MCSA_Global:
+ Symbol->setExternal(true);
+ // This effectively clears the undefined lazy bit, in Darwin 'as', although
+ // it isn't very consistent because it implements this as part of symbol
+ // lookup.
+ //
+ // FIXME: Cleanup this code, these bits should be emitted based on semantic
+ // properties, not on the order of definition, etc.
+ Symbol->setReferenceTypeUndefinedLazy(false);
+ break;
+
+ case MCSA_LazyReference:
+ // FIXME: This requires -dynamic.
+ Symbol->setNoDeadStrip();
+ if (Symbol->isUndefined())
+ Symbol->setReferenceTypeUndefinedLazy(true);
+ break;
+
+ // Since .reference sets the no dead strip bit, it is equivalent to
+ // .no_dead_strip in practice.
+ case MCSA_Reference:
+ case MCSA_NoDeadStrip:
+ Symbol->setNoDeadStrip();
+ break;
+
+ case MCSA_SymbolResolver:
+ Symbol->setSymbolResolver();
+ break;
+
+ case MCSA_AltEntry:
+ Symbol->setAltEntry();
+ break;
+
+ case MCSA_PrivateExtern:
+ Symbol->setExternal(true);
+ Symbol->setPrivateExtern(true);
+ break;
+
+ case MCSA_WeakReference:
+ // FIXME: This requires -dynamic.
+ if (Symbol->isUndefined())
+ Symbol->setWeakReference();
+ break;
+
+ case MCSA_WeakDefinition:
+ // FIXME: 'as' enforces that this is defined and global. The manual claims
+ // it has to be in a coalesced section, but this isn't enforced.
+ Symbol->setWeakDefinition();
+ break;
+
+ case MCSA_WeakDefAutoPrivate:
+ Symbol->setWeakDefinition();
+ Symbol->setWeakReference();
+ break;
+ }
+
+ return true;
+}
+
+void MCMachOStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
+ // Encode the 'desc' value into the lowest implementation defined bits.
+ getAssembler().registerSymbol(*Symbol);
+ cast<MCSymbolMachO>(Symbol)->setDesc(DescValue);
+}
+
+void MCMachOStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+ unsigned ByteAlignment) {
+ // FIXME: Darwin 'as' does appear to allow redef of a .comm by itself.
+ assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
+
+ getAssembler().registerSymbol(*Symbol);
+ Symbol->setExternal(true);
+ Symbol->setCommon(Size, ByteAlignment);
+}
+
+void MCMachOStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+ unsigned ByteAlignment) {
+ // '.lcomm' is equivalent to '.zerofill'.
+ return EmitZerofill(getContext().getObjectFileInfo()->getDataBSSSection(),
+ Symbol, Size, ByteAlignment);
+}
+
+void MCMachOStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
+ uint64_t Size, unsigned ByteAlignment) {
+ getAssembler().registerSection(*Section);
+
+ // The symbol may not be present, which only creates the section.
+ if (!Symbol)
+ return;
+
+ // 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!");
+
+ getAssembler().registerSymbol(*Symbol);
+
+ // Emit an align fragment if necessary.
+ if (ByteAlignment != 1)
+ new MCAlignFragment(ByteAlignment, 0, 0, ByteAlignment, Section);
+
+ MCFragment *F = new MCFillFragment(0, Size, Section);
+ Symbol->setFragment(F);
+
+ // Update the maximum alignment on the zero fill section if necessary.
+ if (ByteAlignment > Section->getAlignment())
+ Section->setAlignment(ByteAlignment);
+}
+
+// This should always be called with the thread local bss section. Like the
+// .zerofill directive this doesn't actually switch sections on us.
+void MCMachOStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
+ uint64_t Size, unsigned ByteAlignment) {
+ EmitZerofill(Section, Symbol, Size, ByteAlignment);
+}
+
+void MCMachOStreamer::EmitInstToData(const MCInst &Inst,
+ const MCSubtargetInfo &STI) {
+ MCDataFragment *DF = getOrCreateDataFragment();
+
+ SmallVector<MCFixup, 4> Fixups;
+ SmallString<256> Code;
+ raw_svector_ostream VecOS(Code);
+ getAssembler().getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
+
+ // Add the fixups and data.
+ for (MCFixup &Fixup : Fixups) {
+ Fixup.setOffset(Fixup.getOffset() + DF->getContents().size());
+ DF->getFixups().push_back(Fixup);
+ }
+ DF->getContents().append(Code.begin(), Code.end());
+}
+
+void MCMachOStreamer::FinishImpl() {
+ EmitFrames(&getAssembler().getBackend());
+
+ // We have to set the fragment atom associations so we can relax properly for
+ // Mach-O.
+
+ // First, scan the symbol table to build a lookup table from fragments to
+ // defining symbols.
+ DenseMap<const MCFragment *, const MCSymbol *> DefiningSymbolMap;
+ for (const MCSymbol &Symbol : getAssembler().symbols()) {
+ if (getAssembler().isSymbolLinkerVisible(Symbol) && Symbol.isInSection() &&
+ !Symbol.isVariable()) {
+ // An atom defining symbol should never be internal to a fragment.
+ assert(Symbol.getOffset() == 0 &&
+ "Invalid offset in atom defining symbol!");
+ DefiningSymbolMap[Symbol.getFragment()] = &Symbol;
+ }
+ }
+
+ // Set the fragment atom associations by tracking the last seen atom defining
+ // symbol.
+ for (MCSection &Sec : getAssembler()) {
+ const MCSymbol *CurrentAtom = nullptr;
+ for (MCFragment &Frag : Sec) {
+ if (const MCSymbol *Symbol = DefiningSymbolMap.lookup(&Frag))
+ CurrentAtom = Symbol;
+ Frag.setAtom(CurrentAtom);
+ }
+ }
+
+ this->MCObjectStreamer::FinishImpl();
+}
+
+MCStreamer *llvm::createMachOStreamer(MCContext &Context, MCAsmBackend &MAB,
+ raw_pwrite_stream &OS, MCCodeEmitter *CE,
+ bool RelaxAll, bool DWARFMustBeAtTheEnd,
+ bool LabelSections) {
+ MCMachOStreamer *S = new MCMachOStreamer(Context, MAB, OS, CE,
+ DWARFMustBeAtTheEnd, LabelSections);
+ const Triple &TT = Context.getObjectFileInfo()->getTargetTriple();
+ if (TT.isOSDarwin()) {
+ unsigned Major, Minor, Update;
+ TT.getOSVersion(Major, Minor, Update);
+ // If there is a version specified, Major will be non-zero.
+ if (Major) {
+ MCVersionMinType VersionType;
+ if (TT.isWatchOS())
+ VersionType = MCVM_WatchOSVersionMin;
+ else if (TT.isTvOS())
+ VersionType = MCVM_TvOSVersionMin;
+ else if (TT.isMacOSX())
+ VersionType = MCVM_OSXVersionMin;
+ else {
+ assert(TT.isiOS() && "Must only be iOS platform left");
+ VersionType = MCVM_IOSVersionMin;
+ }
+ S->EmitVersionMin(VersionType, Major, Minor, Update);
+ }
+ }
+ if (RelaxAll)
+ S->getAssembler().setRelaxAll(true);
+ return S;
+}
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