1 //===- MCObjectStreamer.h - MCStreamer Object File Interface ----*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef LLVM_MC_MCOBJECTSTREAMER_H 11 #define LLVM_MC_MCOBJECTSTREAMER_H 12 13 #include "llvm/MC/MCStreamer.h" 14 15 namespace llvm { 16 class MCAssembler; 17 class MCCodeEmitter; 18 class MCSectionData; 19 class MCExpr; 20 class MCFragment; 21 class MCDataFragment; 22 class MCAsmBackend; 23 class raw_ostream; 24 25 /// \brief Streaming object file generation interface. 26 /// 27 /// This class provides an implementation of the MCStreamer interface which is 28 /// suitable for use with the assembler backend. Specific object file formats 29 /// are expected to subclass this interface to implement directives specific 30 /// to that file format or custom semantics expected by the object writer 31 /// implementation. 32 class MCObjectStreamer : public MCStreamer { 33 MCAssembler *Assembler; 34 MCSectionData *CurSectionData; 35 36 virtual void EmitInstToData(const MCInst &Inst) = 0; 37 virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame); 38 virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame); 39 40 protected: 41 MCObjectStreamer(StreamerKind Kind, MCContext &Context, MCAsmBackend &TAB, 42 raw_ostream &_OS, MCCodeEmitter *_Emitter); 43 MCObjectStreamer(StreamerKind Kind, MCContext &Context, MCAsmBackend &TAB, 44 raw_ostream &_OS, MCCodeEmitter *_Emitter, 45 MCAssembler *_Assembler); 46 ~MCObjectStreamer(); 47 48 public: 49 /// state management 50 virtual void reset(); 51 52 protected: 53 MCSectionData *getCurrentSectionData() const { 54 return CurSectionData; 55 } 56 57 MCFragment *getCurrentFragment() const; 58 59 /// Get a data fragment to write into, creating a new one if the current 60 /// fragment is not a data fragment. 61 MCDataFragment *getOrCreateDataFragment() const; 62 63 const MCExpr *AddValueSymbols(const MCExpr *Value); 64 65 public: 66 MCAssembler &getAssembler() { return *Assembler; } 67 68 /// @name MCStreamer Interface 69 /// @{ 70 71 virtual void EmitLabel(MCSymbol *Symbol); 72 virtual void EmitDebugLabel(MCSymbol *Symbol); 73 virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value); 74 virtual void EmitValueImpl(const MCExpr *Value, unsigned Size, 75 unsigned AddrSpace); 76 virtual void EmitULEB128Value(const MCExpr *Value); 77 virtual void EmitSLEB128Value(const MCExpr *Value); 78 virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol); 79 virtual void ChangeSection(const MCSection *Section); 80 virtual void EmitInstruction(const MCInst &Inst); 81 82 /// \brief Emit an instruction to a special fragment, because this instruction 83 /// can change its size during relaxation. 84 virtual void EmitInstToFragment(const MCInst &Inst); 85 86 virtual void EmitBundleAlignMode(unsigned AlignPow2); 87 virtual void EmitBundleLock(bool AlignToEnd); 88 virtual void EmitBundleUnlock(); 89 virtual void EmitBytes(StringRef Data, unsigned AddrSpace = 0); 90 virtual void EmitValueToAlignment(unsigned ByteAlignment, 91 int64_t Value = 0, 92 unsigned ValueSize = 1, 93 unsigned MaxBytesToEmit = 0); 94 virtual void EmitCodeAlignment(unsigned ByteAlignment, 95 unsigned MaxBytesToEmit = 0); 96 virtual bool EmitValueToOffset(const MCExpr *Offset, unsigned char Value); 97 virtual void EmitDwarfAdvanceLineAddr(int64_t LineDelta, 98 const MCSymbol *LastLabel, 99 const MCSymbol *Label, 100 unsigned PointerSize); 101 virtual void EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel, 102 const MCSymbol *Label); 103 virtual void EmitGPRel32Value(const MCExpr *Value); 104 virtual void EmitGPRel64Value(const MCExpr *Value); 105 virtual void EmitFill(uint64_t NumBytes, uint8_t FillValue, 106 unsigned AddrSpace = 0); 107 virtual void FinishImpl(); 108 109 /// @} 110 111 static bool classof(const MCStreamer *S) { 112 return S->getKind() >= SK_ELFStreamer && S->getKind() <= SK_WinCOFFStreamer; 113 } 114 }; 115 116 } // end namespace llvm 117 118 #endif 119