lld/lib/ReaderWriter/ELF/Writer.cpp

//===- lib/ReaderWriter/ELF/Writer.cpp ------------------------------------===//
//
//                             The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "ExecutableWriter.h"
#include "DynamicLibraryWriter.h"

using namespace llvm;
using namespace llvm::object;

namespace lld {

std::unique_ptr<Writer> createWriterELF(const ELFTargetInfo &TI) {
  using llvm::object::ELFType;
  // Set the default layout to be the static executable layout
  // We would set the layout to a dynamic executable layout
  // if we came across any shared libraries in the process

  const LinkerOptions &options = TI.getLinkerOptions();

  if ((options._outputKind == OutputKind::StaticExecutable) ||
      (options._outputKind == OutputKind::DynamicExecutable)) {
    if (!TI.is64Bits() && TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::ExecutableWriter<ELFType<support::little, 4, false>>(TI));
    else if (TI.is64Bits() && TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::ExecutableWriter<ELFType<support::little, 8, true>>(TI));
    else if (!TI.is64Bits() && !TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::ExecutableWriter<ELFType<support::big, 4, false>>(TI));
    else if (TI.is64Bits() && !TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::ExecutableWriter<ELFType<support::big, 8, true>>(TI));
    llvm_unreachable("Invalid Options!");
  } else if (options._outputKind == OutputKind::Shared) {
    if (!TI.is64Bits() && TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::DynamicLibraryWriter<ELFType<support::little, 4, false>>(TI));
    else if (TI.is64Bits() && TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::DynamicLibraryWriter<ELFType<support::little, 8, true>>(TI));
    else if (!TI.is64Bits() && !TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::DynamicLibraryWriter<ELFType<support::big, 4, false>>(TI));
    else if (TI.is64Bits() && !TI.isLittleEndian())
      return std::unique_ptr<Writer>(new
          elf::DynamicLibraryWriter<ELFType<support::big, 8, true>>(TI));
    llvm_unreachable("Invalid Options!");
  }
  else
    llvm_unreachable("unsupported options");
}
}