llvm-6502/lib/Target/X86/X86ELFWriterInfo.cpp

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//===-- X86ELFWriterInfo.cpp - ELF Writer Info for the X86 backend --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements ELF writer information for the X86 backend.
//
//===----------------------------------------------------------------------===//
#include "X86ELFWriterInfo.h"
#include "X86Relocations.h"
#include "llvm/Function.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
//===----------------------------------------------------------------------===//
// Implementation of the X86ELFWriterInfo class
//===----------------------------------------------------------------------===//
X86ELFWriterInfo::X86ELFWriterInfo(TargetMachine &TM)
: TargetELFWriterInfo(TM) {
bool is64Bit = TM.getTargetData()->getPointerSizeInBits() == 64;
EMachine = is64Bit ? EM_X86_64 : EM_386;
}
X86ELFWriterInfo::~X86ELFWriterInfo() {}
unsigned X86ELFWriterInfo::getRelocationType(unsigned MachineRelTy) const {
if (is64Bit) {
switch(MachineRelTy) {
case X86::reloc_pcrel_word:
return R_X86_64_PC32;
case X86::reloc_absolute_word:
return R_X86_64_32;
case X86::reloc_absolute_dword:
return R_X86_64_64;
case X86::reloc_picrel_word:
default:
assert(0 && "unknown relocation type");
}
} else {
switch(MachineRelTy) {
case X86::reloc_pcrel_word:
return R_386_PC32;
case X86::reloc_absolute_word:
return R_386_32;
case X86::reloc_absolute_dword:
case X86::reloc_picrel_word:
default:
assert(0 && "unknown relocation type");
}
}
return 0;
}
unsigned X86ELFWriterInfo::getFunctionAlignment(const Function *F) const {
unsigned FnAlign = 4;
if (F->hasFnAttr(Attribute::OptimizeForSize))
FnAlign = 1;
if (F->getAlignment())
FnAlign = Log2_32(F->getAlignment());
return (1 << FnAlign);
}
long int X86ELFWriterInfo::getAddendForRelTy(unsigned RelTy) const {
if (is64Bit) {
switch(RelTy) {
case R_X86_64_PC32: return -4;
break;
default:
assert(0 && "unknown x86 relocation type");
}
}
return 0;
}