GeneratePCH.cpp revision 256281 
1//===--- GeneratePCH.cpp - Sema Consumer for PCH Generation -----*- 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 the PCHGenerator, which as a SemaConsumer that generates
11//  a PCH file.
12//
13//===----------------------------------------------------------------------===//
14
15#include "clang/Serialization/ASTWriter.h"
16#include "clang/AST/ASTConsumer.h"
17#include "clang/AST/ASTContext.h"
18#include "clang/Basic/FileManager.h"
19#include "clang/Lex/Preprocessor.h"
20#include "clang/Sema/SemaConsumer.h"
21#include "llvm/Bitcode/BitstreamWriter.h"
22#include "llvm/Support/raw_ostream.h"
23#include <string>
24
25using namespace clang;
26
27PCHGenerator::PCHGenerator(const Preprocessor &PP,
28                           StringRef OutputFile,
29                           clang::Module *Module,
30                           StringRef isysroot,
31                           raw_ostream *OS)
32  : PP(PP), OutputFile(OutputFile), Module(Module),
33    isysroot(isysroot.str()), Out(OS),
34    SemaPtr(0), Stream(Buffer), Writer(Stream) {
35}
36
37PCHGenerator::~PCHGenerator() {
38}
39
40void PCHGenerator::HandleTranslationUnit(ASTContext &Ctx) {
41  if (PP.getDiagnostics().hasErrorOccurred())
42    return;
43
44  // Emit the PCH file
45  assert(SemaPtr && "No Sema?");
46  Writer.WriteAST(*SemaPtr, OutputFile, Module, isysroot);
47
48  // Write the generated bitstream to "Out".
49  Out->write((char *)&Buffer.front(), Buffer.size());
50
51  // Make sure it hits disk now.
52  Out->flush();
53
54  // Free up some memory, in case the process is kept alive.
55  Buffer.clear();
56}
57
58ASTMutationListener *PCHGenerator::GetASTMutationListener() {
59  return &Writer;
60}
61
62ASTDeserializationListener *PCHGenerator::GetASTDeserializationListener() {
63  return &Writer;
64}
65