contrib/llvm/tools/clang/lib/Frontend/PCHContainerOperations.cpp

   1 //===--- Frontend/PCHContainerOperations.cpp - PCH Containers ---*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 //  This file defines PCHContainerOperations and RawPCHContainerOperation.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "clang/Frontend/PCHContainerOperations.h"
  15 #include "clang/AST/ASTConsumer.h"
  16 #include "llvm/Bitcode/BitstreamReader.h"
  17 #include "llvm/Support/raw_ostream.h"
  18 #include "clang/Lex/ModuleLoader.h"
  19
  20 using namespace clang;
  21
  22 namespace {
  23
  24 /// \brief A PCHContainerGenerator that writes out the PCH to a flat file.
  25 class RawPCHContainerGenerator : public ASTConsumer {
  26   std::shared_ptr<PCHBuffer> Buffer;
  27   raw_pwrite_stream *OS;
  28
  29 public:
  30   RawPCHContainerGenerator(llvm::raw_pwrite_stream *OS,
  31                            std::shared_ptr<PCHBuffer> Buffer)
  32       : Buffer(Buffer), OS(OS) {}
  33
  34   ~RawPCHContainerGenerator() override = default;
  35
  36   void HandleTranslationUnit(ASTContext &Ctx) override {
  37     if (Buffer->IsComplete) {
  38       // Make sure it hits disk now.
  39       *OS << Buffer->Data;
  40       OS->flush();
  41     }
  42     // Free the space of the temporary buffer.
  43     llvm::SmallVector<char, 0> Empty;
  44     Buffer->Data = std::move(Empty);
  45   }
  46 };
  47
  48 } // anonymous namespace
  49
  50 std::unique_ptr<ASTConsumer> RawPCHContainerWriter::CreatePCHContainerGenerator(
  51     CompilerInstance &CI, const std::string &MainFileName,
  52     const std::string &OutputFileName, llvm::raw_pwrite_stream *OS,
  53     std::shared_ptr<PCHBuffer> Buffer) const {
  54   return llvm::make_unique<RawPCHContainerGenerator>(OS, Buffer);
  55 }
  56
  57 void RawPCHContainerReader::ExtractPCH(
  58     llvm::MemoryBufferRef Buffer, llvm::BitstreamReader &StreamFile) const {
  59   StreamFile.init((const unsigned char *)Buffer.getBufferStart(),
  60                   (const unsigned char *)Buffer.getBufferEnd());
  61 }
  62
  63 PCHContainerOperations::PCHContainerOperations() {
  64   registerWriter(llvm::make_unique<RawPCHContainerWriter>());
  65   registerReader(llvm::make_unique<RawPCHContainerReader>());
  66 }