lld/wasm/LTO.h

   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 wasm
  10 // file by compiling them using LLVM.
  11 //
  12 // If LTO is in use, your input files are not in regular wasm 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 // a wasm file that contains native code. This file provides that
  16 // functionality.
  17 //
  18 //===----------------------------------------------------------------------===//
  19
  20 #ifndef LLD_WASM_LTO_H
  21 #define LLD_WASM_LTO_H
  22
  23 #include "Writer.h"
  24 #include "lld/Common/LLVM.h"
  25 #include "llvm/ADT/DenseSet.h"
  26 #include "llvm/ADT/SmallString.h"
  27 #include "llvm/Support/raw_ostream.h"
  28 #include <memory>
  29 #include <vector>
  30
  31 namespace llvm {
  32 namespace lto {
  33 class LTO;
  34 }
  35 } // namespace llvm
  36
  37 namespace lld::wasm {
  38
  39 class BitcodeFile;
  40 class InputFile;
  41
  42 class BitcodeCompiler {
  43 public:
  44   BitcodeCompiler();
  45   ~BitcodeCompiler();
  46
  47   void add(BitcodeFile &f);
  48   std::vector<StringRef> compile();
  49
  50 private:
  51   std::unique_ptr<llvm::lto::LTO> ltoObj;
  52   // An array of (module name, native relocatable file content) pairs.
  53   SmallVector<std::pair<std::string, SmallString<0>>, 0> buf;
  54   std::vector<std::unique_ptr<MemoryBuffer>> files;
  55   std::unique_ptr<llvm::raw_fd_ostream> indexFile;
  56   llvm::DenseSet<StringRef> thinIndices;
  57 };
  58 } // namespace lld::wasm
  59
  60 #endif