-//===- lib/MC/MCMachOStreamer.cpp - Mach-O Object Output ------------===//
+//===-- MCMachOStreamer.cpp - MachO Streamer ------------------------------===//
//
// The LLVM Compiler Infrastructure
//
//===----------------------------------------------------------------------===//
#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/MCSectionMachO.h"
#include "llvm/MC/MCSymbol.h"
-#include "llvm/MC/MCValue.h"
+#include "llvm/Support/Dwarf.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
+
using namespace llvm;
namespace {
-class MCMachOStreamer : public MCStreamer {
- /// SymbolFlags - We store the value for the 'desc' symbol field in the lowest
- /// 16 bits of the implementation defined flags.
- enum SymbolFlags { // See <mach-o/nlist.h>.
- SF_DescFlagsMask = 0xFFFF,
-
- // Reference type flags.
- SF_ReferenceTypeMask = 0x0007,
- SF_ReferenceTypeUndefinedNonLazy = 0x0000,
- SF_ReferenceTypeUndefinedLazy = 0x0001,
- SF_ReferenceTypeDefined = 0x0002,
- SF_ReferenceTypePrivateDefined = 0x0003,
- SF_ReferenceTypePrivateUndefinedNonLazy = 0x0004,
- SF_ReferenceTypePrivateUndefinedLazy = 0x0005,
-
- // Other 'desc' flags.
- SF_NoDeadStrip = 0x0020,
- SF_WeakReference = 0x0040,
- SF_WeakDefinition = 0x0080
- };
-
-private:
- MCAssembler Assembler;
-
- MCCodeEmitter *Emitter;
-
- MCSectionData *CurSectionData;
-
- DenseMap<const MCSection*, MCSectionData*> SectionMap;
-
- DenseMap<const MCSymbol*, MCSymbolData*> SymbolMap;
-
+class MCMachOStreamer : public MCObjectStreamer {
private:
- MCFragment *getCurrentFragment() const {
- assert(CurSectionData && "No current section!");
-
- if (!CurSectionData->empty())
- return &CurSectionData->getFragmentList().back();
+ /// 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;
- return 0;
- }
+ /// 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;
- MCSectionData &getSectionData(const MCSection &Section) {
- MCSectionData *&Entry = SectionMap[&Section];
+ void EmitInstToData(const MCInst &Inst, const MCSubtargetInfo &STI) override;
- if (!Entry)
- Entry = new MCSectionData(Section, &Assembler);
-
- return *Entry;
- }
-
- MCSymbolData &getSymbolData(const MCSymbol &Symbol) {
- MCSymbolData *&Entry = SymbolMap[&Symbol];
-
- if (!Entry)
- Entry = new MCSymbolData(Symbol, 0, 0, &Assembler);
-
- return *Entry;
- }
+ void EmitDataRegion(DataRegionData::KindTy Kind);
+ void EmitDataRegionEnd();
public:
- MCMachOStreamer(MCContext &Context, raw_ostream &_OS, MCCodeEmitter *_Emitter)
- : MCStreamer(Context), Assembler(Context, _OS), Emitter(_Emitter),
- CurSectionData(0) {}
- ~MCMachOStreamer() {}
-
- const MCExpr *AddValueSymbols(const MCExpr *Value) {
- switch (Value->getKind()) {
- case MCExpr::Constant:
- break;
-
- case MCExpr::Binary: {
- const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
- AddValueSymbols(BE->getLHS());
- AddValueSymbols(BE->getRHS());
- break;
- }
-
- case MCExpr::SymbolRef:
- getSymbolData(cast<MCSymbolRefExpr>(Value)->getSymbol());
- break;
-
- case MCExpr::Unary:
- AddValueSymbols(cast<MCUnaryExpr>(Value)->getSubExpr());
- break;
- }
-
- return Value;
+ MCMachOStreamer(MCContext &Context, MCAsmBackend &MAB, raw_ostream &OS,
+ MCCodeEmitter *Emitter, bool label)
+ : MCObjectStreamer(Context, MAB, OS, Emitter),
+ LabelSections(label) {}
+
+ /// state management
+ void reset() override {
+ HasSectionLabel.clear();
+ MCObjectStreamer::reset();
}
/// @name MCStreamer Interface
/// @{
- virtual void SwitchSection(const MCSection *Section);
-
- virtual void EmitLabel(MCSymbol *Symbol);
-
- virtual void EmitAssemblerFlag(AssemblerFlag Flag);
-
- virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
-
- virtual void EmitSymbolAttribute(MCSymbol *Symbol, SymbolAttr Attribute);
-
- virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
-
- virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
- unsigned ByteAlignment);
-
- virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
- unsigned Size = 0, unsigned ByteAlignment = 0);
-
- virtual void EmitBytes(const StringRef &Data);
-
- virtual void EmitValue(const MCExpr *Value, unsigned Size);
-
- virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
- unsigned ValueSize = 1,
- unsigned MaxBytesToEmit = 0);
-
- virtual void EmitValueToOffset(const MCExpr *Offset,
- unsigned char Value = 0);
+ 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<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 EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) override {
+ llvm_unreachable("macho doesn't support this directive");
+ }
+ 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'");
+ }
- virtual void EmitInstruction(const MCInst &Inst);
+ void EmitIdent(StringRef IdentString) override {
+ llvm_unreachable("macho doesn't support this directive");
+ }
- virtual void Finish();
+ void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) override {
+ getAssembler().getLOHContainer().addDirective(Kind, Args);
+ }
- /// @}
+ void FinishImpl() override;
};
} // end anonymous namespace.
-void MCMachOStreamer::SwitchSection(const MCSection *Section) {
- assert(Section && "Cannot switch to a null section!");
-
- // If already in this section, then this is a noop.
- if (Section == CurSection) return;
+void MCMachOStreamer::ChangeSection(const MCSection *Section,
+ const MCExpr *Subsection) {
+ // Change the section normally.
+ MCObjectStreamer::ChangeSection(Section, Subsection);
+ // 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;
+ }
+}
- CurSection = Section;
- CurSectionData = &getSectionData(*Section);
+void MCMachOStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
+ MCSymbol *EHSymbol) {
+ MCSymbolData &SD =
+ getAssembler().getOrCreateSymbolData(*Symbol);
+ if (SD.isExternal())
+ EmitSymbolAttribute(EHSymbol, MCSA_Global);
+ if (SD.getFlags() & SF_WeakDefinition)
+ EmitSymbolAttribute(EHSymbol, MCSA_WeakDefinition);
+ if (SD.isPrivateExtern())
+ EmitSymbolAttribute(EHSymbol, MCSA_PrivateExtern);
}
void MCMachOStreamer::EmitLabel(MCSymbol *Symbol) {
assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
- // FIXME: We should also use offsets into Fill fragments.
- MCDataFragment *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
- if (!F)
- F = new MCDataFragment(CurSectionData);
+ // isSymbolLinkerVisible uses the section.
+ 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))
+ insert(new MCDataFragment());
- MCSymbolData &SD = getSymbolData(*Symbol);
- assert(!SD.getFragment() && "Unexpected fragment on symbol data!");
- SD.setFragment(F);
- SD.setOffset(F->getContents().size());
+ MCObjectStreamer::EmitLabel(Symbol);
- // This causes the reference type and weak reference flags to be cleared.
- SD.setFlags(SD.getFlags() & ~(SF_WeakReference | SF_ReferenceTypeMask));
-
- Symbol->setSection(*CurSection);
+ MCSymbolData &SD = getAssembler().getSymbolData(*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.
+ SD.setFlags(SD.getFlags() & ~SF_ReferenceTypeMask);
}
-void MCMachOStreamer::EmitAssemblerFlag(AssemblerFlag Flag) {
+void MCMachOStreamer::EmitDataRegion(DataRegionData::KindTy Kind) {
+ if (!getAssembler().getBackend().hasDataInCodeSupport())
+ return;
+ // 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() {
+ if (!getAssembler().getBackend().hasDataInCodeSupport())
+ return;
+ 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 SubsectionsViaSymbols:
- Assembler.setSubsectionsViaSymbols(true);
+ 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;
}
+}
- assert(0 && "invalid assembler flag!");
+void MCMachOStreamer::EmitLinkerOptions(ArrayRef<std::string> Options) {
+ getAssembler().getLinkerOptions().push_back(Options);
}
-void MCMachOStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
- // Only absolute symbols can be redefined.
- assert((Symbol->isUndefined() || Symbol->isAbsolute()) &&
- "Cannot define a symbol twice!");
+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);
+}
- llvm_unreachable("FIXME: Not yet implemented!");
+void MCMachOStreamer::EmitThumbFunc(MCSymbol *Symbol) {
+ // Remember that the function is a thumb function. Fixup and relocation
+ // values will need adjusted.
+ getAssembler().setIsThumbFunc(Symbol);
}
-void MCMachOStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
- SymbolAttr Attribute) {
+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.
- if (Attribute == MCStreamer::IndirectSymbol) {
+ 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.SectionData = CurSectionData;
- Assembler.getIndirectSymbols().push_back(ISD);
- return;
+ ISD.SectionData = getCurrentSectionData();
+ getAssembler().getIndirectSymbols().push_back(ISD);
+ return true;
}
// Adding a symbol attribute always introduces the symbol, note that an
- // important side effect of calling getSymbolData here is to register the
- // symbol with the assembler.
- MCSymbolData &SD = getSymbolData(*Symbol);
+ // important side effect of calling getOrCreateSymbolData here is to register
+ // the symbol with the assembler.
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*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
// In the future it might be worth trying to make these operations more well
// defined.
switch (Attribute) {
- case MCStreamer::IndirectSymbol:
- case MCStreamer::Hidden:
- case MCStreamer::Internal:
- case MCStreamer::Protected:
- case MCStreamer::Weak:
- assert(0 && "Invalid symbol attribute for Mach-O!");
- break;
-
- case MCStreamer::Global:
+ 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:
SD.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.
+ SD.setFlags(SD.getFlags() & ~SF_ReferenceTypeUndefinedLazy);
break;
- case MCStreamer::LazyReference:
+ case MCSA_LazyReference:
// FIXME: This requires -dynamic.
SD.setFlags(SD.getFlags() | SF_NoDeadStrip);
if (Symbol->isUndefined())
// Since .reference sets the no dead strip bit, it is equivalent to
// .no_dead_strip in practice.
- case MCStreamer::Reference:
- case MCStreamer::NoDeadStrip:
+ case MCSA_Reference:
+ case MCSA_NoDeadStrip:
SD.setFlags(SD.getFlags() | SF_NoDeadStrip);
break;
- case MCStreamer::PrivateExtern:
+ case MCSA_SymbolResolver:
+ SD.setFlags(SD.getFlags() | SF_SymbolResolver);
+ break;
+
+ case MCSA_PrivateExtern:
SD.setExternal(true);
SD.setPrivateExtern(true);
break;
- case MCStreamer::WeakReference:
+ case MCSA_WeakReference:
// FIXME: This requires -dynamic.
if (Symbol->isUndefined())
SD.setFlags(SD.getFlags() | SF_WeakReference);
break;
- case MCStreamer::WeakDefinition:
+ 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.
SD.setFlags(SD.getFlags() | SF_WeakDefinition);
break;
+
+ case MCSA_WeakDefAutoPrivate:
+ SD.setFlags(SD.getFlags() | SF_WeakDefinition | SF_WeakReference);
+ break;
}
+
+ return true;
}
void MCMachOStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
// Encode the 'desc' value into the lowest implementation defined bits.
- assert(DescValue == (DescValue & SF_DescFlagsMask) &&
+ assert(DescValue == (DescValue & SF_DescFlagsMask) &&
"Invalid .desc value!");
- getSymbolData(*Symbol).setFlags(DescValue & SF_DescFlagsMask);
+ getAssembler().getOrCreateSymbolData(*Symbol).setFlags(
+ DescValue & SF_DescFlagsMask);
}
-void MCMachOStreamer::EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
+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!");
- MCSymbolData &SD = getSymbolData(*Symbol);
+ AssignSection(Symbol, nullptr);
+
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
SD.setExternal(true);
SD.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(const MCSection *Section, MCSymbol *Symbol,
- unsigned Size, unsigned ByteAlignment) {
- MCSectionData &SectData = getSectionData(*Section);
+ uint64_t Size, unsigned ByteAlignment) {
+ MCSectionData &SectData = getAssembler().getOrCreateSectionData(*Section);
// The symbol may not be present, which only creates the section.
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!");
- MCSymbolData &SD = getSymbolData(*Symbol);
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+
+ // Emit an align fragment if necessary.
+ if (ByteAlignment != 1)
+ new MCAlignFragment(ByteAlignment, 0, 0, ByteAlignment, &SectData);
- MCFragment *F = new MCZeroFillFragment(Size, ByteAlignment, &SectData);
+ 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())
SectData.setAlignment(ByteAlignment);
}
-void MCMachOStreamer::EmitBytes(const StringRef &Data) {
- MCDataFragment *DF = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
- if (!DF)
- DF = new MCDataFragment(CurSectionData);
- DF->getContents().append(Data.begin(), Data.end());
-}
-
-void MCMachOStreamer::EmitValue(const MCExpr *Value, unsigned Size) {
- MCValue RelocValue;
-
- if (!AddValueSymbols(Value)->EvaluateAsRelocatable(getContext(), RelocValue))
- return llvm_report_error("expected relocatable expression");
-
- new MCFillFragment(RelocValue, Size, 1, CurSectionData);
-}
-
-void MCMachOStreamer::EmitValueToAlignment(unsigned ByteAlignment,
- int64_t Value, unsigned ValueSize,
- unsigned MaxBytesToEmit) {
- if (MaxBytesToEmit == 0)
- MaxBytesToEmit = ByteAlignment;
- new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit,
- CurSectionData);
-
- // Update the maximum alignment on the current section if necessary.
- if (ByteAlignment > CurSectionData->getAlignment())
- CurSectionData->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(const MCSection *Section, MCSymbol *Symbol,
+ uint64_t Size, unsigned ByteAlignment) {
+ EmitZerofill(Section, Symbol, Size, ByteAlignment);
+ return;
}
-void MCMachOStreamer::EmitValueToOffset(const MCExpr *Offset,
- unsigned char Value) {
- MCValue RelocOffset;
+void MCMachOStreamer::EmitInstToData(const MCInst &Inst,
+ const MCSubtargetInfo &STI) {
+ MCDataFragment *DF = getOrCreateDataFragment();
- if (!AddValueSymbols(Offset)->EvaluateAsRelocatable(RelocOffset))
- return llvm_report_error("expected relocatable expression");
+ SmallVector<MCFixup, 4> Fixups;
+ SmallString<256> Code;
+ raw_svector_ostream VecOS(Code);
+ getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, Fixups, STI);
+ VecOS.flush();
- new MCOrgFragment(RelocOffset, Value, CurSectionData);
+ // 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->getFixups().push_back(Fixups[i]);
+ }
+ DF->getContents().append(Code.begin(), Code.end());
}
-void MCMachOStreamer::EmitInstruction(const MCInst &Inst) {
- // Scan for values.
- for (unsigned i = 0; i != Inst.getNumOperands(); ++i)
- if (Inst.getOperand(i).isExpr())
- AddValueSymbols(Inst.getOperand(i).getExpr());
-
- if (!Emitter)
- llvm_unreachable("no code emitter available!");
+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*, MCSymbolData*> DefiningSymbolMap;
+ for (MCSymbolData &SD : getAssembler().symbols()) {
+ if (getAssembler().isSymbolLinkerVisible(SD.getSymbol()) &&
+ SD.getFragment()) {
+ // An atom defining symbol should never be internal to a fragment.
+ assert(SD.getOffset() == 0 && "Invalid offset in atom defining symbol!");
+ DefiningSymbolMap[SD.getFragment()] = &SD;
+ }
+ }
- // FIXME: Relocations!
- SmallString<256> Code;
- raw_svector_ostream VecOS(Code);
- Emitter->EncodeInstruction(Inst, VecOS);
- EmitBytes(VecOS.str());
-}
+ // Set the fragment atom associations by tracking the last seen atom defining
+ // symbol.
+ for (MCAssembler::iterator it = getAssembler().begin(),
+ ie = getAssembler().end(); it != ie; ++it) {
+ MCSymbolData *CurrentAtom = nullptr;
+ for (MCSectionData::iterator it2 = it->begin(),
+ ie2 = it->end(); it2 != ie2; ++it2) {
+ if (MCSymbolData *SD = DefiningSymbolMap.lookup(it2))
+ CurrentAtom = SD;
+ it2->setAtom(CurrentAtom);
+ }
+ }
-void MCMachOStreamer::Finish() {
- Assembler.Finish();
+ this->MCObjectStreamer::FinishImpl();
}
-MCStreamer *llvm::createMachOStreamer(MCContext &Context, raw_ostream &OS,
- MCCodeEmitter *CE) {
- return new MCMachOStreamer(Context, OS, CE);
+MCStreamer *llvm::createMachOStreamer(MCContext &Context, MCAsmBackend &MAB,
+ raw_ostream &OS, MCCodeEmitter *CE,
+ bool RelaxAll,
+ bool LabelSections) {
+ MCMachOStreamer *S = new MCMachOStreamer(Context, MAB, OS, CE, LabelSections);
+ if (RelaxAll)
+ S->getAssembler().setRelaxAll(true);
+ return S;
}