MCNullStreamer.cpp revision dce4a407a24b04eebc6a376f8e62b41aaa7b071f 
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#include "llvm/MC/MCContext.h"
12#include "llvm/MC/MCInst.h"
13#include "llvm/MC/MCSectionMachO.h"
14#include "llvm/MC/MCSymbol.h"
15
16using namespace llvm;
17
18namespace {
19
20  class MCNullStreamer : public MCStreamer {
21  public:
22    MCNullStreamer(MCContext &Context) : MCStreamer(Context) {}
23
24    /// @name MCStreamer Interface
25    /// @{
26
27    void ChangeSection(const MCSection *Section,
28                       const MCExpr *Subsection) override {
29    }
30
31    void EmitLabel(MCSymbol *Symbol) override {
32      assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
33      assert(getCurrentSection().first &&"Cannot emit before setting section!");
34      AssignSection(Symbol, getCurrentSection().first);
35    }
36    void EmitDebugLabel(MCSymbol *Symbol) override {
37      EmitLabel(Symbol);
38    }
39    void EmitAssemblerFlag(MCAssemblerFlag Flag) override {}
40    void EmitThumbFunc(MCSymbol *Func) override {}
41
42    void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override {}
43    void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override {}
44    bool EmitSymbolAttribute(MCSymbol *Symbol,
45                             MCSymbolAttr Attribute) override {
46      return true;
47    }
48
49    void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override {}
50
51    void BeginCOFFSymbolDef(const MCSymbol *Symbol) override {}
52    void EmitCOFFSymbolStorageClass(int StorageClass) override {}
53    void EmitCOFFSymbolType(int Type) override {}
54    void EndCOFFSymbolDef() override {}
55    void EmitCOFFSecRel32(MCSymbol const *Symbol) override {}
56
57    void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) override {}
58    void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
59                          unsigned ByteAlignment) override {}
60    void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
61                               unsigned ByteAlignment) override {}
62    void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = nullptr,
63                      uint64_t Size = 0, unsigned ByteAlignment = 0) override {}
64    void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
65                        uint64_t Size, unsigned ByteAlignment) override {}
66    void EmitBytes(StringRef Data) override {}
67
68    void EmitValueImpl(const MCExpr *Value, unsigned Size,
69                       const SMLoc &Loc = SMLoc()) override {}
70    void EmitULEB128Value(const MCExpr *Value) override {}
71    void EmitSLEB128Value(const MCExpr *Value) override {}
72    void EmitGPRel32Value(const MCExpr *Value) override {}
73    void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
74                              unsigned ValueSize = 1,
75                              unsigned MaxBytesToEmit = 0) override {}
76
77    void EmitCodeAlignment(unsigned ByteAlignment,
78                           unsigned MaxBytesToEmit = 0) override {}
79
80    bool EmitValueToOffset(const MCExpr *Offset,
81                           unsigned char Value = 0) override { return false; }
82
83    void EmitFileDirective(StringRef Filename) override {}
84    unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
85                                    StringRef Filename,
86                                    unsigned CUID = 0) override {
87      return 0;
88    }
89    void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
90                               unsigned Column, unsigned Flags,
91                               unsigned Isa, unsigned Discriminator,
92                               StringRef FileName) override {}
93    void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo&) override {}
94
95    void EmitBundleAlignMode(unsigned AlignPow2) override {}
96    void EmitBundleLock(bool AlignToEnd) override {}
97    void EmitBundleUnlock() override {}
98
99    void FinishImpl() override {}
100
101    void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override {
102      RecordProcEnd(Frame);
103    }
104  };
105
106}
107
108MCStreamer *llvm::createNullStreamer(MCContext &Context) {
109  return new MCNullStreamer(Context);
110}
111