#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/Support/Dwarf.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetAsmBackend.h"
+#include "llvm/Target/TargetAsmInfo.h"
using namespace llvm;
class MCMachOStreamer : public MCObjectStreamer {
private:
- /// Track the current atom for each section.
- DenseMap<const MCSectionData*, MCSymbolData*> CurrentAtomMap;
-
-private:
- MCFragment *getCurrentFragment() const {
- assert(getCurrentSectionData() && "No current section!");
-
- if (!getCurrentSectionData()->empty())
- return &getCurrentSectionData()->getFragmentList().back();
-
- return 0;
- }
-
- /// Get a data fragment to write into, creating a new one if the current
- /// fragment is not a data fragment.
- MCDataFragment *getOrCreateDataFragment() const {
- MCDataFragment *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
- if (!F)
- F = createDataFragment();
- return F;
- }
-
- /// Create a new data fragment in the current section.
- MCDataFragment *createDataFragment() const {
- MCDataFragment *DF = new MCDataFragment(getCurrentSectionData());
- DF->setAtom(CurrentAtomMap.lookup(getCurrentSectionData()));
- return DF;
- }
-
- void EmitInstToFragment(const MCInst &Inst);
- void EmitInstToData(const MCInst &Inst);
+ virtual void EmitInstToData(const MCInst &Inst);
public:
MCMachOStreamer(MCContext &Context, TargetAsmBackend &TAB,
raw_ostream &OS, MCCodeEmitter *Emitter)
: MCObjectStreamer(Context, TAB, OS, Emitter) {}
- const MCExpr *AddValueSymbols(const MCExpr *Value) {
- switch (Value->getKind()) {
- case MCExpr::Target: assert(0 && "Can't handle target exprs yet!");
- case MCExpr::Constant:
- break;
-
- case MCExpr::Binary: {
- const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
- AddValueSymbols(BE->getLHS());
- AddValueSymbols(BE->getRHS());
- break;
- }
-
- case MCExpr::SymbolRef:
- getAssembler().getOrCreateSymbolData(
- cast<MCSymbolRefExpr>(Value)->getSymbol());
- break;
-
- case MCExpr::Unary:
- AddValueSymbols(cast<MCUnaryExpr>(Value)->getSubExpr());
- break;
- }
-
- return Value;
- }
-
/// @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 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 EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment = 0);
virtual void EmitBytes(StringRef Data, unsigned AddrSpace);
- virtual void EmitValue(const MCExpr *Value, unsigned Size,unsigned AddrSpace);
- virtual void EmitGPRel32Value(const MCExpr *Value) {
- assert(0 && "macho doesn't support this directive");
- }
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 EmitValueToOffset(const MCExpr *Offset,
- unsigned char Value = 0);
virtual void EmitFileDirective(StringRef Filename) {
- report_fatal_error("unsupported directive: '.file'");
- }
- virtual void EmitDwarfFileDirective(unsigned FileNo, StringRef Filename) {
- report_fatal_error("unsupported directive: '.file'");
+ // 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);
+ virtual void Finish();
/// @}
};
} // end anonymous namespace.
-void MCMachOStreamer::EmitLabel(MCSymbol *Symbol) {
- assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
- assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
- assert(CurSection && "Cannot emit before setting section!");
+void MCMachOStreamer::InitSections() {
+ SwitchSection(getContext().getMachOSection("__TEXT", "__text",
+ MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
+ 0, SectionKind::getText()));
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+}
- // Update the current atom map, if necessary.
- bool MustCreateFragment = false;
- if (getAssembler().isSymbolLinkerVisible(&SD)) {
- CurrentAtomMap[getCurrentSectionData()] = &SD;
+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);
+}
- // We have to create a new fragment, fragments cannot span atoms.
- MustCreateFragment = true;
- }
+void MCMachOStreamer::EmitLabel(MCSymbol *Symbol) {
+ assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
- // FIXME: This is wasteful, we don't necessarily need to create a data
- // fragment. Instead, we should mark the symbol as pointing into the data
- // fragment if it exists, otherwise we should just queue the label and set its
- // fragment pointer when we emit the next fragment.
- MCDataFragment *F =
- MustCreateFragment ? createDataFragment() : getOrCreateDataFragment();
- assert(!SD.getFragment() && "Unexpected fragment on symbol data!");
- SD.setFragment(F);
- SD.setOffset(F->getContents().size());
+ // isSymbolLinkerVisible uses the section.
+ Symbol->setSection(*getCurrentSection());
+ // 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());
+ MCObjectStreamer::EmitLabel(Symbol);
+
+ 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
// 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);
-
- Symbol->setSection(*CurSection);
}
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; // no-op here.
+ case MCAF_Code32: return; // no-op here.
case MCAF_SubsectionsViaSymbols:
getAssembler().setSubsectionsViaSymbols(true);
return;
+ default:
+ llvm_unreachable("invalid assembler flag!");
}
+}
+
+void MCMachOStreamer::EmitThumbFunc(MCSymbol *Symbol) {
+ // FIXME: Flag the function ISA as thumb with DW_AT_APPLE_isa.
- assert(0 && "invalid assembler flag!");
+ // 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));
case MCSA_ELF_TypeTLS:
case MCSA_ELF_TypeCommon:
case MCSA_ELF_TypeNoType:
+ case MCSA_ELF_TypeGnuUniqueObject:
case MCSA_IndirectSymbol:
case MCSA_Hidden:
case MCSA_Internal:
SD.setFlags(SD.getFlags() | SF_NoDeadStrip);
break;
+ case MCSA_SymbolResolver:
+ SD.setFlags(SD.getFlags() | SF_SymbolResolver);
+ break;
+
case MCSA_PrivateExtern:
SD.setExternal(true);
SD.setPrivateExtern(true);
// 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;
}
}
MCFragment *F = new MCFillFragment(0, 0, Size, &SectData);
SD.setFragment(F);
- if (getAssembler().isSymbolLinkerVisible(&SD))
- F->setAtom(&SD);
Symbol->setSection(*Section);
}
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::EmitValue(const MCExpr *Value, unsigned Size,
- unsigned AddrSpace) {
- MCDataFragment *DF = getOrCreateDataFragment();
-
- // Avoid fixups when possible.
- int64_t AbsValue;
- if (AddValueSymbols(Value)->EvaluateAsAbsolute(AbsValue)) {
- // FIXME: Endianness assumption.
- for (unsigned i = 0; i != Size; ++i)
- DF->getContents().push_back(uint8_t(AbsValue >> (i * 8)));
- } else {
- DF->addFixup(MCFixup::Create(DF->getContents().size(),
- AddValueSymbols(Value),
- MCFixup::getKindForSize(Size)));
- DF->getContents().resize(DF->getContents().size() + Size, 0);
- }
-}
-
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;
- MCFragment *F = new MCAlignFragment(ByteAlignment, Value, ValueSize,
- MaxBytesToEmit, getCurrentSectionData());
- F->setAtom(CurrentAtomMap.lookup(getCurrentSectionData()));
+ new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit,
+ getCurrentSectionData());
// Update the maximum alignment on the current section if necessary.
if (ByteAlignment > getCurrentSectionData()->getAlignment())
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);
- F->setAtom(CurrentAtomMap.lookup(getCurrentSectionData()));
// Update the maximum alignment on the current section if necessary.
if (ByteAlignment > getCurrentSectionData()->getAlignment())
getCurrentSectionData()->setAlignment(ByteAlignment);
}
-void MCMachOStreamer::EmitValueToOffset(const MCExpr *Offset,
- unsigned char Value) {
- MCFragment *F = new MCOrgFragment(*Offset, Value, getCurrentSectionData());
- F->setAtom(CurrentAtomMap.lookup(getCurrentSectionData()));
-}
-
-void MCMachOStreamer::EmitInstToFragment(const MCInst &Inst) {
- MCInstFragment *IF = new MCInstFragment(Inst, getCurrentSectionData());
- IF->setAtom(CurrentAtomMap.lookup(getCurrentSectionData()));
-
- // Add the fixups and data.
- //
- // FIXME: Revisit this design decision when relaxation is done, we may be
- // able to get away with not storing any extra data in the MCInst.
- SmallVector<MCFixup, 4> Fixups;
- SmallString<256> Code;
- raw_svector_ostream VecOS(Code);
- getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, Fixups);
- VecOS.flush();
-
- IF->getCode() = Code;
- IF->getFixups() = Fixups;
-}
-
void MCMachOStreamer::EmitInstToData(const MCInst &Inst) {
MCDataFragment *DF = getOrCreateDataFragment();
DF->getContents().append(Code.begin(), Code.end());
}
-void MCMachOStreamer::EmitInstruction(const MCInst &Inst) {
- // Scan for values.
- for (unsigned i = Inst.getNumOperands(); i--; )
- if (Inst.getOperand(i).isExpr())
- AddValueSymbols(Inst.getOperand(i).getExpr());
-
- getCurrentSectionData()->setHasInstructions(true);
-
- // If this instruction doesn't need relaxation, just emit it as data.
- if (!getAssembler().getBackend().MayNeedRelaxation(Inst)) {
- EmitInstToData(Inst);
- return;
+void MCMachOStreamer::Finish() {
+ if (getNumFrameInfos())
+ MCDwarfFrameEmitter::Emit(*this, true);
+
+ // 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 (MCAssembler::symbol_iterator it = getAssembler().symbol_begin(),
+ ie = getAssembler().symbol_end(); it != ie; ++it) {
+ if (getAssembler().isSymbolLinkerVisible(it->getSymbol()) &&
+ it->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;
+ }
}
- // Otherwise, if we are relaxing everything, relax the instruction as much as
- // possible and emit it as data.
- if (getAssembler().getRelaxAll()) {
- MCInst Relaxed;
- getAssembler().getBackend().RelaxInstruction(Inst, Relaxed);
- while (getAssembler().getBackend().MayNeedRelaxation(Relaxed))
- getAssembler().getBackend().RelaxInstruction(Relaxed, Relaxed);
- EmitInstToData(Relaxed);
- return;
+ // 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 = 0;
+ for (MCSectionData::iterator it2 = it->begin(),
+ ie2 = it->end(); it2 != ie2; ++it2) {
+ if (MCSymbolData *SD = DefiningSymbolMap.lookup(it2))
+ CurrentAtom = SD;
+ it2->setAtom(CurrentAtom);
+ }
}
- // Otherwise emit to a separate fragment.
- EmitInstToFragment(Inst);
+ this->MCObjectStreamer::Finish();
}
MCStreamer *llvm::createMachOStreamer(MCContext &Context, TargetAsmBackend &TAB,