1//===- lib/MC/MCNullStreamer.cpp - Dummy Streamer Implementation ----------===//
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#include "llvm/MC/MCStreamer.h"
11
12#include "llvm/MC/MCContext.h"
13#include "llvm/MC/MCInst.h"
14#include "llvm/MC/MCSectionMachO.h"
15#include "llvm/MC/MCSymbol.h"
16
17using namespace llvm;
18
19namespace {
20
21  class MCNullStreamer : public MCStreamer {
22  public:
23    MCNullStreamer(MCContext &Context) : MCStreamer(Context) {}
24
25    /// @name MCStreamer Interface
26    /// @{
27
28    virtual void InitSections() {
29    }
30
31    virtual void ChangeSection(const MCSection *Section) {
32    }
33
34    virtual void EmitLabel(MCSymbol *Symbol) {
35      assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
36      assert(getCurrentSection() && "Cannot emit before setting section!");
37      Symbol->setSection(*getCurrentSection());
38    }
39
40    virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) {}
41    virtual void EmitThumbFunc(MCSymbol *Func) {}
42
43    virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {}
44    virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol){}
45    virtual void EmitDwarfAdvanceLineAddr(int64_t LineDelta,
46                                          const MCSymbol *LastLabel,
47                                          const MCSymbol *Label,
48                                          unsigned PointerSize) {}
49
50    virtual void EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute){}
51
52    virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
53
54    virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol) {}
55    virtual void EmitCOFFSymbolStorageClass(int StorageClass) {}
56    virtual void EmitCOFFSymbolType(int Type) {}
57    virtual void EndCOFFSymbolDef() {}
58    virtual void EmitCOFFSecRel32(MCSymbol const *Symbol) {}
59
60    virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
61    virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
62                                  unsigned ByteAlignment) {}
63    virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
64                                       unsigned ByteAlignment) {}
65    virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
66                              uint64_t Size = 0, unsigned ByteAlignment = 0) {}
67    virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
68                                uint64_t Size, unsigned ByteAlignment) {}
69    virtual void EmitBytes(StringRef Data, unsigned AddrSpace) {}
70
71    virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
72                               unsigned AddrSpace) {}
73    virtual void EmitULEB128Value(const MCExpr *Value) {}
74    virtual void EmitSLEB128Value(const MCExpr *Value) {}
75    virtual void EmitGPRel32Value(const MCExpr *Value) {}
76    virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
77                                      unsigned ValueSize = 1,
78                                      unsigned MaxBytesToEmit = 0) {}
79
80    virtual void EmitCodeAlignment(unsigned ByteAlignment,
81                                   unsigned MaxBytesToEmit = 0) {}
82
83    virtual bool EmitValueToOffset(const MCExpr *Offset,
84                                   unsigned char Value = 0) { return false; }
85
86    virtual void EmitFileDirective(StringRef Filename) {}
87    virtual bool EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
88                                        StringRef Filename) {
89      return false;
90    }
91    virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
92                                       unsigned Column, unsigned Flags,
93                                       unsigned Isa, unsigned Discriminator,
94                                       StringRef FileName) {}
95    virtual void EmitInstruction(const MCInst &Inst) {}
96
97    virtual void FinishImpl() {}
98
99    virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
100      RecordProcEnd(Frame);
101    }
102
103    /// @}
104  };
105
106}
107
108MCStreamer *llvm::createNullStreamer(MCContext &Context) {
109  return new MCNullStreamer(Context);
110}
111