lib/MC/MCNullStreamer.cpp

   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
  17 using namespace llvm;
  18
  19 namespace {
  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 SwitchSection(const MCSection *Section) {
  32       PrevSection = CurSection;
  33       CurSection = Section;
  34     }
  35
  36     virtual void EmitLabel(MCSymbol *Symbol) {
  37       assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
  38       assert(CurSection && "Cannot emit before setting section!");
  39       Symbol->setSection(*CurSection);
  40     }
  41
  42     virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) {}
  43
  44     virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {}
  45     virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol){}
  46
  47     virtual void EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute){}
  48
  49     virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
  50
  51     virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol) {}
  52     virtual void EmitCOFFSymbolStorageClass(int StorageClass) {}
  53     virtual void EmitCOFFSymbolType(int Type) {}
  54     virtual void EndCOFFSymbolDef() {}
  55
  56     virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
  57     virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
  58                                   unsigned ByteAlignment) {}
  59     virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size) {}
  60
  61     virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
  62                               unsigned Size = 0, unsigned ByteAlignment = 0) {}
  63     virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
  64                                 uint64_t Size, unsigned ByteAlignment) {}
  65     virtual void EmitBytes(StringRef Data, unsigned AddrSpace) {}
  66
  67     virtual void EmitValue(const MCExpr *Value, unsigned Size,
  68                            unsigned AddrSpace) {}
  69     virtual void EmitULEB128Value(const MCExpr *Value,
  70                                   unsigned AddrSpace = 0) {}
  71     virtual void EmitSLEB128Value(const MCExpr *Value,
  72                                   unsigned AddrSpace = 0) {}
  73     virtual void EmitGPRel32Value(const MCExpr *Value) {}
  74     virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
  75                                       unsigned ValueSize = 1,
  76                                       unsigned MaxBytesToEmit = 0) {}
  77
  78     virtual void EmitCodeAlignment(unsigned ByteAlignment,
  79                                    unsigned MaxBytesToEmit = 0) {}
  80
  81     virtual void EmitValueToOffset(const MCExpr *Offset,
  82                                    unsigned char Value = 0) {}
  83
  84     virtual void EmitFileDirective(StringRef Filename) {}
  85     virtual void EmitDwarfFileDirective(unsigned FileNo,StringRef Filename) {}
  86     virtual void EmitInstruction(const MCInst &Inst) {}
  87
  88     virtual void Finish() {}
  89
  90     /// @}
  91   };
  92
  93 }
  94
  95 MCStreamer *llvm::createNullStreamer(MCContext &Context) {
  96   return new MCNullStreamer(Context);
  97 }