llvm/lib/Object/ELFObjectFile.cpp
2014-07-31 03:12:45 +00:00

87 lines
3.0 KiB
C++

//===- ELFObjectFile.cpp - ELF object file implementation -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Part of the ELFObjectFile class implementation.
//
//===----------------------------------------------------------------------===//
#include "llvm/Object/ELFObjectFile.h"
#include "llvm/Support/MathExtras.h"
namespace llvm {
using namespace object;
ErrorOr<std::unique_ptr<ObjectFile>>
ObjectFile::createELFObjectFile(std::unique_ptr<MemoryBuffer> &Obj) {
std::pair<unsigned char, unsigned char> Ident =
getElfArchType(Obj->getBuffer());
std::size_t MaxAlignment =
1ULL << countTrailingZeros(uintptr_t(Obj->getBufferStart()));
std::error_code EC;
std::unique_ptr<ObjectFile> R;
if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB)
#if !LLVM_IS_UNALIGNED_ACCESS_FAST
if (MaxAlignment >= 4)
R.reset(new ELFObjectFile<ELFType<support::little, 4, false>>(
std::move(Obj), EC));
else
#endif
if (MaxAlignment >= 2)
R.reset(new ELFObjectFile<ELFType<support::little, 2, false>>(
std::move(Obj), EC));
else
return object_error::parse_failed;
else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB)
#if !LLVM_IS_UNALIGNED_ACCESS_FAST
if (MaxAlignment >= 4)
R.reset(new ELFObjectFile<ELFType<support::big, 4, false>>(std::move(Obj),
EC));
else
#endif
if (MaxAlignment >= 2)
R.reset(new ELFObjectFile<ELFType<support::big, 2, false>>(std::move(Obj),
EC));
else
return object_error::parse_failed;
else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB)
#if !LLVM_IS_UNALIGNED_ACCESS_FAST
if (MaxAlignment >= 8)
R.reset(new ELFObjectFile<ELFType<support::big, 8, true>>(std::move(Obj),
EC));
else
#endif
if (MaxAlignment >= 2)
R.reset(new ELFObjectFile<ELFType<support::big, 2, true>>(std::move(Obj),
EC));
else
return object_error::parse_failed;
else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) {
#if !LLVM_IS_UNALIGNED_ACCESS_FAST
if (MaxAlignment >= 8)
R.reset(new ELFObjectFile<ELFType<support::little, 8, true>>(
std::move(Obj), EC));
else
#endif
if (MaxAlignment >= 2)
R.reset(new ELFObjectFile<ELFType<support::little, 2, true>>(
std::move(Obj), EC));
else
return object_error::parse_failed;
}
else
llvm_unreachable("Buffer is not an ELF object file!");
if (EC)
return EC;
return std::move(R);
}
} // end namespace llvm