diff options
Diffstat (limited to 'lib/MC/MCAsmStreamer.cpp')
| -rw-r--r-- | lib/MC/MCAsmStreamer.cpp | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp new file mode 100644 index 0000000..e38f2b3 --- /dev/null +++ b/lib/MC/MCAsmStreamer.cpp @@ -0,0 +1,206 @@ +//===- lib/MC/MCAsmStreamer.cpp - Text Assembly Output --------------------===// +// +// 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/MC/MCContext.h" +#include "llvm/MC/MCSection.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/MC/MCValue.h" +#include "llvm/Support/raw_ostream.h" +using namespace llvm; + +namespace { + + class MCAsmStreamer : public MCStreamer { + raw_ostream &OS; + + MCSection *CurSection; + + public: + MCAsmStreamer(MCContext &Context, raw_ostream &_OS) + : MCStreamer(Context), OS(_OS) {} + ~MCAsmStreamer() {} + + /// @name MCStreamer Interface + /// @{ + + virtual void SwitchSection(MCSection *Section); + + virtual void EmitLabel(MCSymbol *Symbol); + + virtual void EmitAssignment(MCSymbol *Symbol, const MCValue &Value, + bool MakeAbsolute = false); + + virtual void EmitSymbolAttribute(MCSymbol *Symbol, SymbolAttr Attribute); + + virtual void EmitBytes(const char *Data, unsigned Length); + + virtual void EmitValue(const MCValue &Value, unsigned Size); + + virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0, + unsigned ValueSize = 1, + unsigned MaxBytesToEmit = 0); + + virtual void EmitValueToOffset(const MCValue &Offset, + unsigned char Value = 0); + + virtual void EmitInstruction(const MCInst &Inst); + + virtual void Finish(); + + /// @} + }; + +} + +/// Allow printing values directly to a raw_ostream. +static inline raw_ostream &operator<<(raw_ostream &os, const MCValue &Value) { + if (Value.getSymA()) { + os << Value.getSymA()->getName(); + if (Value.getSymB()) + os << " - " << Value.getSymB()->getName(); + if (Value.getCst()) + os << " + " << Value.getCst(); + } else { + assert(!Value.getSymB() && "Invalid machine code value!"); + os << Value.getCst(); + } + + return os; +} + +static inline int64_t truncateToSize(int64_t Value, unsigned Bytes) { + assert(Bytes && "Invalid size!"); + return Value & ((uint64_t) (int64_t) -1 >> (64 - Bytes * 8)); +} + +static inline MCValue truncateToSize(const MCValue &Value, unsigned Bytes) { + return MCValue::get(Value.getSymA(), Value.getSymB(), + truncateToSize(Value.getCst(), Bytes)); +} + +void MCAsmStreamer::SwitchSection(MCSection *Section) { + if (Section != CurSection) { + CurSection = Section; + + // FIXME: Really we would like the segment, flags, etc. to be separate + // values instead of embedded in the name. Not all assemblers understand all + // this stuff though. + OS << ".section " << Section->getName() << "\n"; + } +} + +void MCAsmStreamer::EmitLabel(MCSymbol *Symbol) { + assert(Symbol->getSection() == 0 && "Cannot emit a symbol twice!"); + assert(CurSection && "Cannot emit before setting section!"); + assert(!getContext().GetSymbolValue(Symbol) && + "Cannot emit symbol which was directly assigned to!"); + + OS << Symbol->getName() << ":\n"; + Symbol->setSection(CurSection); +} + +void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCValue &Value, + bool MakeAbsolute) { + assert(!Symbol->getSection() && "Cannot assign to a label!"); + + if (MakeAbsolute) { + OS << ".set " << Symbol->getName() << ", " << Value << '\n'; + } else { + OS << Symbol->getName() << " = " << Value << '\n'; + } + + getContext().SetSymbolValue(Symbol, Value); +} + +void MCAsmStreamer::EmitSymbolAttribute(MCSymbol *Symbol, + SymbolAttr Attribute) { + switch (Attribute) { + case Global: OS << ".globl"; break; + case Hidden: OS << ".hidden"; break; + case IndirectSymbol: OS << ".indirect_symbol"; break; + case Internal: OS << ".internal"; break; + case LazyReference: OS << ".lazy_reference"; break; + case NoDeadStrip: OS << ".no_dead_strip"; break; + case PrivateExtern: OS << ".private_extern"; break; + case Protected: OS << ".protected"; break; + case Reference: OS << ".reference"; break; + case Weak: OS << ".weak"; break; + case WeakDefinition: OS << ".weak_definition"; break; + case WeakReference: OS << ".weak_reference"; break; + } + + OS << ' ' << Symbol->getName() << '\n'; +} + +void MCAsmStreamer::EmitBytes(const char *Data, unsigned Length) { + assert(CurSection && "Cannot emit contents before setting section!"); + for (unsigned i = 0; i != Length; ++i) + OS << ".byte " << (unsigned) Data[i] << '\n'; +} + +void MCAsmStreamer::EmitValue(const MCValue &Value, unsigned Size) { + assert(CurSection && "Cannot emit contents before setting section!"); + // Need target hooks to know how to print this. + switch (Size) { + default: + assert(0 && "Invalid size for machine code value!"); + case 1: OS << ".byte"; break; + case 2: OS << ".short"; break; + case 4: OS << ".long"; break; + case 8: OS << ".quad"; break; + } + + OS << ' ' << truncateToSize(Value, Size) << '\n'; +} + +void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value, + unsigned ValueSize, + unsigned MaxBytesToEmit) { + unsigned Pow2 = Log2_32(ByteAlignment); + assert((1U << Pow2) == ByteAlignment && "Invalid alignment!"); + + switch (ValueSize) { + default: + assert(0 && "Invalid size for machine code value!"); + case 8: + assert(0 && "Unsupported alignment size!"); + case 1: OS << ".p2align"; break; + case 2: OS << ".p2alignw"; break; + case 4: OS << ".p2alignl"; break; + } + + OS << ' ' << Pow2; + + OS << ", " << truncateToSize(Value, ValueSize); + if (MaxBytesToEmit) + OS << ", " << MaxBytesToEmit; + OS << '\n'; +} + +void MCAsmStreamer::EmitValueToOffset(const MCValue &Offset, + unsigned char Value) { + // FIXME: Verify that Offset is associated with the current section. + OS << ".org " << Offset << ", " << (unsigned) Value << '\n'; +} + +void MCAsmStreamer::EmitInstruction(const MCInst &Inst) { + assert(CurSection && "Cannot emit contents before setting section!"); + // FIXME: Implement. + OS << "# FIXME: Implement instruction printing!\n"; +} + +void MCAsmStreamer::Finish() { + OS.flush(); +} + +MCStreamer *llvm::createAsmStreamer(MCContext &Context, raw_ostream &OS) { + return new MCAsmStreamer(Context, OS); +} |
