1//===- LTO.h ----------------------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file provides a way to combine bitcode files into one ELF
10// file by compiling them using LLVM.
11//
12// If LTO is in use, your input files are not in regular ELF files
13// but instead LLVM bitcode files. In that case, the linker has to
14// convert bitcode files into the native format so that we can create
15// an ELF file that contains native code. This file provides that
16// functionality.
17//
18//===----------------------------------------------------------------------===//
19
20#ifndef LLD_ELF_LTO_H
21#define LLD_ELF_LTO_H
22
23#include "lld/Common/LLVM.h"
24#include "llvm/ADT/DenseSet.h"
25#include "llvm/ADT/SmallString.h"
26#include "llvm/Support/raw_ostream.h"
27#include <memory>
28#include <vector>
29
30namespace llvm::lto {
31class LTO;
32}
33
34namespace lld::elf {
35
36class BitcodeFile;
37class InputFile;
38
39class BitcodeCompiler {
40public:
41  BitcodeCompiler();
42  ~BitcodeCompiler();
43
44  void add(BitcodeFile &f);
45  std::vector<InputFile *> compile();
46
47private:
48  std::unique_ptr<llvm::lto::LTO> ltoObj;
49  std::vector<SmallString<0>> buf;
50  std::vector<std::unique_ptr<MemoryBuffer>> files;
51  llvm::DenseSet<StringRef> usedStartStop;
52  std::unique_ptr<llvm::raw_fd_ostream> indexFile;
53  llvm::DenseSet<StringRef> thinIndices;
54};
55} // namespace lld::elf
56
57#endif
58