f7669ba3d9
Port COFF's https://reviews.llvm.org/D78221 and https://reviews.llvm.org/D137217 to ELF. For the in-process ThinLTO link, `ld.lld --save-temps a.o d/b.o -o out` will create ELF relocatable files `out.lto.a.o`/`d/out.lto.b.o` instead of `out1.lto.o`/`out2.lto.o`. Deriving the LTO-generated relocatable file name from bitcode file names helps debugging. The relocatable file name from the first regular LTO partition does not change: `out.lto.o`. The second, if present due to `--lto-partition=`, changes from `out1.lto.o` to `lto.1.o`. For an archive member, e.g. `d/a.a(coll.o at 8)`, the relocatable file is `d/out.lto.a.a(coll.o at 8).o`. `--lto-emit-asm` file names are changed similarly. `--lto-emit-asm -o out` now creates `out.lto.s` instead of `out`, therefore the `--lto-emit-asm -o -` idiom no longer works. However, I think this new behavior (which matches COFF) is better since keeping or removing `--lto-emit-asm` will dump different files, instead of overwriting the `-o` output file from an executable/shared object to an assembly file. Reviewers: rnk, igorkudrin, xur-llvm, teresajohnson, ZequanWu Reviewed By: teresajohnson Pull Request: https://github.com/llvm/llvm-project/pull/78835
60 lines
1.7 KiB
C++
60 lines
1.7 KiB
C++
//===- LTO.h ----------------------------------------------------*- C++ -*-===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file provides a way to combine bitcode files into one ELF
|
|
// file by compiling them using LLVM.
|
|
//
|
|
// If LTO is in use, your input files are not in regular ELF files
|
|
// but instead LLVM bitcode files. In that case, the linker has to
|
|
// convert bitcode files into the native format so that we can create
|
|
// an ELF file that contains native code. This file provides that
|
|
// functionality.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLD_ELF_LTO_H
|
|
#define LLD_ELF_LTO_H
|
|
|
|
#include "lld/Common/LLVM.h"
|
|
#include "llvm/ADT/DenseSet.h"
|
|
#include "llvm/ADT/SmallString.h"
|
|
#include "llvm/Support/raw_ostream.h"
|
|
#include <memory>
|
|
#include <vector>
|
|
|
|
namespace llvm::lto {
|
|
class LTO;
|
|
}
|
|
|
|
namespace lld::elf {
|
|
|
|
class BitcodeFile;
|
|
class InputFile;
|
|
|
|
class BitcodeCompiler {
|
|
public:
|
|
BitcodeCompiler();
|
|
~BitcodeCompiler();
|
|
|
|
void add(BitcodeFile &f);
|
|
std::vector<InputFile *> compile();
|
|
|
|
private:
|
|
std::unique_ptr<llvm::lto::LTO> ltoObj;
|
|
// An array of (module name, native relocatable file content) pairs.
|
|
SmallVector<std::pair<std::string, SmallString<0>>, 0> buf;
|
|
std::vector<std::unique_ptr<MemoryBuffer>> files;
|
|
SmallVector<std::string, 0> filenames;
|
|
llvm::DenseSet<StringRef> usedStartStop;
|
|
std::unique_ptr<llvm::raw_fd_ostream> indexFile;
|
|
llvm::DenseSet<StringRef> thinIndices;
|
|
};
|
|
} // namespace lld::elf
|
|
|
|
#endif
|