diff options
Diffstat (limited to 'contrib/llvm/lib/MC/MCObjectStreamer.cpp')
-rw-r--r-- | contrib/llvm/lib/MC/MCObjectStreamer.cpp | 187 |
1 files changed, 177 insertions, 10 deletions
diff --git a/contrib/llvm/lib/MC/MCObjectStreamer.cpp b/contrib/llvm/lib/MC/MCObjectStreamer.cpp index 2b2385e..0358266 100644 --- a/contrib/llvm/lib/MC/MCObjectStreamer.cpp +++ b/contrib/llvm/lib/MC/MCObjectStreamer.cpp @@ -7,19 +7,26 @@ // //===----------------------------------------------------------------------===// +#include "llvm/MC/MCAsmInfo.h" #include "llvm/MC/MCObjectStreamer.h" #include "llvm/Support/ErrorHandling.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/MCSymbol.h" #include "llvm/Target/TargetAsmBackend.h" +#include "llvm/Target/TargetAsmInfo.h" using namespace llvm; MCObjectStreamer::MCObjectStreamer(MCContext &Context, TargetAsmBackend &TAB, - raw_ostream &_OS, MCCodeEmitter *_Emitter) - : MCStreamer(Context), Assembler(new MCAssembler(Context, TAB, - *_Emitter, _OS)), + raw_ostream &OS, MCCodeEmitter *Emitter_) + : MCStreamer(Context), + Assembler(new MCAssembler(Context, TAB, + *Emitter_, *TAB.createObjectWriter(OS), + OS)), CurSectionData(0) { } @@ -27,6 +34,7 @@ MCObjectStreamer::MCObjectStreamer(MCContext &Context, TargetAsmBackend &TAB, MCObjectStreamer::~MCObjectStreamer() { delete &Assembler->getBackend(); delete &Assembler->getEmitter(); + delete &Assembler->getWriter(); delete Assembler; } @@ -48,7 +56,10 @@ MCDataFragment *MCObjectStreamer::getOrCreateDataFragment() const { const MCExpr *MCObjectStreamer::AddValueSymbols(const MCExpr *Value) { switch (Value->getKind()) { - case MCExpr::Target: llvm_unreachable("Can't handle target exprs yet!"); + case MCExpr::Target: + cast<MCTargetExpr>(Value)->AddValueSymbols(Assembler); + break; + case MCExpr::Constant: break; @@ -71,17 +82,173 @@ const MCExpr *MCObjectStreamer::AddValueSymbols(const MCExpr *Value) { return Value; } -void MCObjectStreamer::SwitchSection(const MCSection *Section) { - assert(Section && "Cannot switch to a null section!"); +void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size, + bool isPCRel, unsigned AddrSpace) { + assert(AddrSpace == 0 && "Address space must be 0!"); + MCDataFragment *DF = getOrCreateDataFragment(); + + // Avoid fixups when possible. + int64_t AbsValue; + if (AddValueSymbols(Value)->EvaluateAsAbsolute(AbsValue, getAssembler())) { + EmitIntValue(AbsValue, Size, AddrSpace); + return; + } + DF->addFixup(MCFixup::Create(DF->getContents().size(), + Value, + MCFixup::getKindForSize(Size, isPCRel))); + DF->getContents().resize(DF->getContents().size() + Size, 0); +} + +void MCObjectStreamer::EmitLabel(MCSymbol *Symbol) { + assert(!Symbol->isVariable() && "Cannot emit a variable symbol!"); + assert(getCurrentSection() && "Cannot emit before setting section!"); + + Symbol->setSection(*getCurrentSection()); + + MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol); + + // 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 = getOrCreateDataFragment(); + assert(!SD.getFragment() && "Unexpected fragment on symbol data!"); + SD.setFragment(F); + SD.setOffset(F->getContents().size()); +} + +void MCObjectStreamer::EmitULEB128Value(const MCExpr *Value, + unsigned AddrSpace) { + int64_t IntValue; + if (Value->EvaluateAsAbsolute(IntValue, getAssembler())) { + EmitULEB128IntValue(IntValue, AddrSpace); + return; + } + new MCLEBFragment(*Value, false, getCurrentSectionData()); +} + +void MCObjectStreamer::EmitSLEB128Value(const MCExpr *Value, + unsigned AddrSpace) { + int64_t IntValue; + if (Value->EvaluateAsAbsolute(IntValue, getAssembler())) { + EmitSLEB128IntValue(IntValue, AddrSpace); + return; + } + new MCLEBFragment(*Value, true, getCurrentSectionData()); +} + +void MCObjectStreamer::EmitWeakReference(MCSymbol *Alias, + const MCSymbol *Symbol) { + report_fatal_error("This file format doesn't support weak aliases."); +} - // If already in this section, then this is a noop. - if (Section == CurSection) return; +void MCObjectStreamer::ChangeSection(const MCSection *Section) { + assert(Section && "Cannot switch to a null section!"); - PrevSection = CurSection; - CurSection = Section; CurSectionData = &getAssembler().getOrCreateSectionData(*Section); } +void MCObjectStreamer::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); + + // Now that a machine instruction has been assembled into this section, make + // a line entry for any .loc directive that has been seen. + MCLineEntry::Make(this, getCurrentSection()); + + // If this instruction doesn't need relaxation, just emit it as data. + if (!getAssembler().getBackend().MayNeedRelaxation(Inst)) { + EmitInstToData(Inst); + return; + } + + // 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; + } + + // Otherwise emit to a separate fragment. + EmitInstToFragment(Inst); +} + +void MCObjectStreamer::EmitInstToFragment(const MCInst &Inst) { + MCInstFragment *IF = new MCInstFragment(Inst, getCurrentSectionData()); + + raw_svector_ostream VecOS(IF->getCode()); + getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, IF->getFixups()); +} + +static const MCExpr *BuildSymbolDiff(MCContext &Context, + const MCSymbol *A, const MCSymbol *B) { + MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None; + const MCExpr *ARef = + MCSymbolRefExpr::Create(A, Variant, Context); + const MCExpr *BRef = + MCSymbolRefExpr::Create(B, Variant, Context); + const MCExpr *AddrDelta = + MCBinaryExpr::Create(MCBinaryExpr::Sub, ARef, BRef, Context); + return AddrDelta; +} + +static const MCExpr *ForceExpAbs(MCObjectStreamer *Streamer, + MCContext &Context, const MCExpr* Expr) { + if (Context.getAsmInfo().hasAggressiveSymbolFolding()) + return Expr; + + MCSymbol *ABS = Context.CreateTempSymbol(); + Streamer->EmitAssignment(ABS, Expr); + return MCSymbolRefExpr::Create(ABS, Context); +} + +void MCObjectStreamer::EmitDwarfAdvanceLineAddr(int64_t LineDelta, + const MCSymbol *LastLabel, + const MCSymbol *Label) { + if (!LastLabel) { + int PointerSize = getContext().getTargetAsmInfo().getPointerSize(); + EmitDwarfSetLineAddr(LineDelta, Label, PointerSize); + return; + } + const MCExpr *AddrDelta = BuildSymbolDiff(getContext(), Label, LastLabel); + int64_t Res; + if (AddrDelta->EvaluateAsAbsolute(Res, getAssembler())) { + MCDwarfLineAddr::Emit(this, LineDelta, Res); + return; + } + AddrDelta = ForceExpAbs(this, getContext(), AddrDelta); + new MCDwarfLineAddrFragment(LineDelta, *AddrDelta, getCurrentSectionData()); +} + +void MCObjectStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel, + const MCSymbol *Label) { + const MCExpr *AddrDelta = BuildSymbolDiff(getContext(), Label, LastLabel); + int64_t Res; + if (AddrDelta->EvaluateAsAbsolute(Res, getAssembler())) { + MCDwarfFrameEmitter::EmitAdvanceLoc(*this, Res); + return; + } + AddrDelta = ForceExpAbs(this, getContext(), AddrDelta); + new MCDwarfCallFrameFragment(*AddrDelta, getCurrentSectionData()); +} + +void MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset, + unsigned char Value) { + new MCOrgFragment(*Offset, Value, getCurrentSectionData()); +} + void MCObjectStreamer::Finish() { + // Dump out the dwarf file & directory tables and line tables. + if (getContext().hasDwarfFiles()) + MCDwarfFileTable::Emit(this); + getAssembler().Finish(); } |