llvm/lib/MC/MCNullStreamer.cpp
Kevin Enderby 6e72048add This is the first patch to put the needed bits in place to eventually allow code
to be aligned with optimal nops.  This patch does not change any functionality
and when the compiler is changed to use EmitCodeAlignment() it should also not
change the resulting output.  Once the compiler change is made and everything
looks good the next patch with the table of optimal X86 nops will be added to
WriteNopData() changing the output.  There are many FIXMEs in this patch which
will be removed when we have better target hooks (coming soon I hear).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96963 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-23 18:26:34 +00:00

78 lines
2.6 KiB
C++

//===- lib/MC/MCNullStreamer.cpp - Dummy Streamer Implementation ----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCSymbol.h"
using namespace llvm;
namespace {
class MCNullStreamer : public MCStreamer {
public:
MCNullStreamer(MCContext &Context) : MCStreamer(Context) {}
/// @name MCStreamer Interface
/// @{
virtual void SwitchSection(const MCSection *Section) {
CurSection = Section;
}
virtual void EmitLabel(MCSymbol *Symbol) {}
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) {}
virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {}
virtual void EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute){}
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment) {}
virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size) {}
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
unsigned Size = 0, unsigned ByteAlignment = 0) {}
virtual void EmitBytes(StringRef Data, unsigned AddrSpace) {}
virtual void EmitValue(const MCExpr *Value, unsigned Size,
unsigned AddrSpace) {}
virtual void EmitGPRel32Value(const MCExpr *Value) {}
virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
unsigned ValueSize = 1,
unsigned MaxBytesToEmit = 0) {}
virtual void EmitCodeAlignment(unsigned ByteAlignment,
unsigned MaxBytesToEmit = 0) {}
virtual void EmitValueToOffset(const MCExpr *Offset,
unsigned char Value = 0) {}
virtual void EmitFileDirective(StringRef Filename) {}
virtual void EmitDwarfFileDirective(unsigned FileNo,StringRef Filename) {}
virtual void EmitInstruction(const MCInst &Inst) {}
virtual void Finish() {}
/// @}
};
}
MCStreamer *llvm::createNullStreamer(MCContext &Context) {
return new MCNullStreamer(Context);
}