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 <string>
23 
24 using namespace clang;
25 
26 PCHGenerator::PCHGenerator(const Preprocessor &PP,
27                            StringRef OutputFile,
28                            clang::Module *Module,
29                            StringRef isysroot,
30                            bool AllowASTWithErrors)
31   : PP(PP), OutputFile(OutputFile), Module(Module),
32     isysroot(isysroot.str()),
33     SemaPtr(nullptr), Stream(Buffer),
34     Writer(Stream),
35     AllowASTWithErrors(AllowASTWithErrors),
36     HasEmittedPCH(false) {
37 }
38 
39 PCHGenerator::~PCHGenerator() {
40 }
41 
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   if (SerializationFinishedCallback)
56     SerializationFinishedCallback(&Buffer);
57 
58   HasEmittedPCH = true;
59 }
60 
61 ASTMutationListener *PCHGenerator::GetASTMutationListener() {
62   return &Writer;
63 }
64 
65 ASTDeserializationListener *PCHGenerator::GetASTDeserializationListener() {
66   return &Writer;
67 }
68