MCObjectStreamer.h revision ca1dd05c3c12e857614ae6837f90894396225dd6 
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
15namespace llvm {
16class MCAssembler;
17class MCCodeEmitter;
18class MCSectionData;
19class MCExpr;
20class MCFragment;
21class MCDataFragment;
22class MCAsmBackend;
23class 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.
32class 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
40protected:
41  MCObjectStreamer(MCContext &Context, MCAsmBackend &TAB,
42                   raw_ostream &_OS, MCCodeEmitter *_Emitter);
43  MCObjectStreamer(MCContext &Context, MCAsmBackend &TAB,
44                   raw_ostream &_OS, MCCodeEmitter *_Emitter,
45                   MCAssembler *_Assembler);
46  ~MCObjectStreamer();
47
48public:
49  /// state management
50  virtual void reset();
51
52protected:
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
65public:
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
112} // end namespace llvm
113
114#endif
115