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 
27 PCHGenerator::PCHGenerator(const Preprocessor &PP, StringRef OutputFile,
28                            clang::Module *Module, StringRef isysroot,
29                            std::shared_ptr<PCHBuffer> Buffer,
30                            bool AllowASTWithErrors)
31     : PP(PP), OutputFile(OutputFile), Module(Module), isysroot(isysroot.str()),
32       SemaPtr(nullptr), Buffer(Buffer), Stream(Buffer->Data), Writer(Stream),
33       AllowASTWithErrors(AllowASTWithErrors) {
34   Buffer->IsComplete = false;
35 }
36 
37 PCHGenerator::~PCHGenerator() {
38 }
39 
40 void PCHGenerator::HandleTranslationUnit(ASTContext &Ctx) {
41   // Don't create a PCH if there were fatal failures during module loading.
42   if (PP.getModuleLoader().HadFatalFailure)
43     return;
44 
45   bool hasErrors = PP.getDiagnostics().hasErrorOccurred();
46   if (hasErrors && !AllowASTWithErrors)
47     return;
48 
49   // Emit the PCH file to the Buffer.
50   assert(SemaPtr && "No Sema?");
51   Writer.WriteAST(*SemaPtr, OutputFile, Module, isysroot, hasErrors);
52 
53   Buffer->IsComplete = true;
54 }
55 
56 ASTMutationListener *PCHGenerator::GetASTMutationListener() {
57   return &Writer;
58 }
59 
60 ASTDeserializationListener *PCHGenerator::GetASTDeserializationListener() {
61   return &Writer;
62 }
63