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
25 using namespace clang;
26
PCHGenerator(const Preprocessor & PP,StringRef OutputFile,clang::Module * Module,StringRef isysroot,raw_ostream * OS,bool AllowASTWithErrors)27 PCHGenerator::PCHGenerator(const Preprocessor &PP,
28 StringRef OutputFile,
29 clang::Module *Module,
30 StringRef isysroot,
31 raw_ostream *OS, bool AllowASTWithErrors)
32 : PP(PP), OutputFile(OutputFile), Module(Module),
33 isysroot(isysroot.str()), Out(OS),
34 SemaPtr(nullptr), Stream(Buffer), Writer(Stream),
35 AllowASTWithErrors(AllowASTWithErrors),
36 HasEmittedPCH(false) {
37 }
38
~PCHGenerator()39 PCHGenerator::~PCHGenerator() {
40 }
41
HandleTranslationUnit(ASTContext & Ctx)42 void PCHGenerator::HandleTranslationUnit(ASTContext &Ctx) {
43 // Don't create a PCH if there were fatal failures during module loading.
44 if (PP.getModuleLoader().HadFatalFailure)
45 return;
46
47 bool hasErrors = PP.getDiagnostics().hasErrorOccurred();
48 if (hasErrors && !AllowASTWithErrors)
49 return;
50
51 // Emit the PCH file
52 assert(SemaPtr && "No Sema?");
53 Writer.WriteAST(*SemaPtr, OutputFile, Module, isysroot, hasErrors);
54
55 // Write the generated bitstream to "Out".
56 Out->write((char *)&Buffer.front(), Buffer.size());
57
58 // Make sure it hits disk now.
59 Out->flush();
60
61 // Free up some memory, in case the process is kept alive.
62 Buffer.clear();
63
64 HasEmittedPCH = true;
65 }
66
GetASTMutationListener()67 ASTMutationListener *PCHGenerator::GetASTMutationListener() {
68 return &Writer;
69 }
70
GetASTDeserializationListener()71 ASTDeserializationListener *PCHGenerator::GetASTDeserializationListener() {
72 return &Writer;
73 }
74