xref: /freebsd/contrib/llvm-project/clang/lib/Serialization/PCHContainerOperations.cpp (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
1 //=== Serialization/PCHContainerOperations.cpp - PCH Containers -*- 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 defines PCHContainerOperations and RawPCHContainerOperation.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/Serialization/PCHContainerOperations.h"
14 #include "clang/AST/ASTConsumer.h"
15 #include "clang/Lex/ModuleLoader.h"
16 #include "llvm/Bitstream/BitstreamReader.h"
17 #include "llvm/Support/raw_ostream.h"
18 #include <utility>
19 
20 using namespace clang;
21 
22 PCHContainerWriter::~PCHContainerWriter() {}
23 PCHContainerReader::~PCHContainerReader() {}
24 
25 namespace {
26 
27 /// A PCHContainerGenerator that writes out the PCH to a flat file.
28 class RawPCHContainerGenerator : public ASTConsumer {
29   std::shared_ptr<PCHBuffer> Buffer;
30   std::unique_ptr<raw_pwrite_stream> OS;
31 
32 public:
33   RawPCHContainerGenerator(std::unique_ptr<llvm::raw_pwrite_stream> OS,
34                            std::shared_ptr<PCHBuffer> Buffer)
35       : Buffer(std::move(Buffer)), OS(std::move(OS)) {}
36 
37   ~RawPCHContainerGenerator() override = default;
38 
39   void HandleTranslationUnit(ASTContext &Ctx) override {
40     if (Buffer->IsComplete) {
41       // Make sure it hits disk now.
42       *OS << Buffer->Data;
43       OS->flush();
44     }
45     // Free the space of the temporary buffer.
46     llvm::SmallVector<char, 0> Empty;
47     Buffer->Data = std::move(Empty);
48   }
49 };
50 
51 } // anonymous namespace
52 
53 std::unique_ptr<ASTConsumer> RawPCHContainerWriter::CreatePCHContainerGenerator(
54     CompilerInstance &CI, const std::string &MainFileName,
55     const std::string &OutputFileName, std::unique_ptr<llvm::raw_pwrite_stream> OS,
56     std::shared_ptr<PCHBuffer> Buffer) const {
57   return std::make_unique<RawPCHContainerGenerator>(std::move(OS), Buffer);
58 }
59 
60 StringRef
61 RawPCHContainerReader::ExtractPCH(llvm::MemoryBufferRef Buffer) const {
62   return Buffer.getBuffer();
63 }
64 
65 PCHContainerOperations::PCHContainerOperations() {
66   registerWriter(std::make_unique<RawPCHContainerWriter>());
67   registerReader(std::make_unique<RawPCHContainerReader>());
68 }
69