1 //===- ChainedIncludesSource.cpp - Chained PCHs in Memory -------*- 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 the ChainedIncludesSource class, which converts headers 10 // to chained PCHs in memory, mainly used for testing. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "clang/Basic/Builtins.h" 15 #include "clang/Basic/TargetInfo.h" 16 #include "clang/Frontend/ASTUnit.h" 17 #include "clang/Frontend/CompilerInstance.h" 18 #include "clang/Frontend/TextDiagnosticPrinter.h" 19 #include "clang/Lex/Preprocessor.h" 20 #include "clang/Lex/PreprocessorOptions.h" 21 #include "clang/Parse/ParseAST.h" 22 #include "clang/Sema/MultiplexExternalSemaSource.h" 23 #include "clang/Serialization/ASTReader.h" 24 #include "clang/Serialization/ASTWriter.h" 25 #include "llvm/Support/MemoryBuffer.h" 26 27 using namespace clang; 28 29 namespace { 30 class ChainedIncludesSourceImpl : public ExternalSemaSource { 31 public: 32 ChainedIncludesSourceImpl(std::vector<std::unique_ptr<CompilerInstance>> CIs) 33 : CIs(std::move(CIs)) {} 34 35 protected: 36 //===----------------------------------------------------------------------===// 37 // ExternalASTSource interface. 38 //===----------------------------------------------------------------------===// 39 40 /// Return the amount of memory used by memory buffers, breaking down 41 /// by heap-backed versus mmap'ed memory. 42 void getMemoryBufferSizes(MemoryBufferSizes &sizes) const override { 43 for (unsigned i = 0, e = CIs.size(); i != e; ++i) { 44 if (const ExternalASTSource *eSrc = 45 CIs[i]->getASTContext().getExternalSource()) { 46 eSrc->getMemoryBufferSizes(sizes); 47 } 48 } 49 } 50 51 private: 52 std::vector<std::unique_ptr<CompilerInstance>> CIs; 53 }; 54 55 /// Members of ChainedIncludesSource, factored out so we can initialize 56 /// them before we initialize the ExternalSemaSource base class. 57 struct ChainedIncludesSourceMembers { 58 ChainedIncludesSourceMembers( 59 std::vector<std::unique_ptr<CompilerInstance>> CIs, 60 IntrusiveRefCntPtr<ExternalSemaSource> FinalReader) 61 : Impl(std::move(CIs)), FinalReader(std::move(FinalReader)) {} 62 ChainedIncludesSourceImpl Impl; 63 IntrusiveRefCntPtr<ExternalSemaSource> FinalReader; 64 }; 65 66 /// Use MultiplexExternalSemaSource to dispatch all ExternalSemaSource 67 /// calls to the final reader. 68 class ChainedIncludesSource 69 : private ChainedIncludesSourceMembers, 70 public MultiplexExternalSemaSource { 71 public: 72 ChainedIncludesSource(std::vector<std::unique_ptr<CompilerInstance>> CIs, 73 IntrusiveRefCntPtr<ExternalSemaSource> FinalReader) 74 : ChainedIncludesSourceMembers(std::move(CIs), std::move(FinalReader)), 75 MultiplexExternalSemaSource(Impl, *this->FinalReader) {} 76 }; 77 } 78 79 static ASTReader * 80 createASTReader(CompilerInstance &CI, StringRef pchFile, 81 SmallVectorImpl<std::unique_ptr<llvm::MemoryBuffer>> &MemBufs, 82 SmallVectorImpl<std::string> &bufNames, 83 ASTDeserializationListener *deserialListener = nullptr) { 84 Preprocessor &PP = CI.getPreprocessor(); 85 std::unique_ptr<ASTReader> Reader; 86 Reader.reset(new ASTReader( 87 PP, CI.getModuleCache(), &CI.getASTContext(), CI.getPCHContainerReader(), 88 /*Extensions=*/{}, 89 /*isysroot=*/"", DisableValidationForModuleKind::PCH)); 90 for (unsigned ti = 0; ti < bufNames.size(); ++ti) { 91 StringRef sr(bufNames[ti]); 92 Reader->addInMemoryBuffer(sr, std::move(MemBufs[ti])); 93 } 94 Reader->setDeserializationListener(deserialListener); 95 switch (Reader->ReadAST(pchFile, serialization::MK_PCH, SourceLocation(), 96 ASTReader::ARR_None)) { 97 case ASTReader::Success: 98 // Set the predefines buffer as suggested by the PCH reader. 99 PP.setPredefines(Reader->getSuggestedPredefines()); 100 return Reader.release(); 101 102 case ASTReader::Failure: 103 case ASTReader::Missing: 104 case ASTReader::OutOfDate: 105 case ASTReader::VersionMismatch: 106 case ASTReader::ConfigurationMismatch: 107 case ASTReader::HadErrors: 108 break; 109 } 110 return nullptr; 111 } 112 113 IntrusiveRefCntPtr<ExternalSemaSource> clang::createChainedIncludesSource( 114 CompilerInstance &CI, IntrusiveRefCntPtr<ExternalSemaSource> &Reader) { 115 116 std::vector<std::string> &includes = CI.getPreprocessorOpts().ChainedIncludes; 117 assert(!includes.empty() && "No '-chain-include' in options!"); 118 119 std::vector<std::unique_ptr<CompilerInstance>> CIs; 120 InputKind IK = CI.getFrontendOpts().Inputs[0].getKind(); 121 122 SmallVector<std::unique_ptr<llvm::MemoryBuffer>, 4> SerialBufs; 123 SmallVector<std::string, 4> serialBufNames; 124 125 for (unsigned i = 0, e = includes.size(); i != e; ++i) { 126 bool firstInclude = (i == 0); 127 std::unique_ptr<CompilerInvocation> CInvok; 128 CInvok.reset(new CompilerInvocation(CI.getInvocation())); 129 130 CInvok->getPreprocessorOpts().ChainedIncludes.clear(); 131 CInvok->getPreprocessorOpts().ImplicitPCHInclude.clear(); 132 CInvok->getPreprocessorOpts().DisablePCHOrModuleValidation = 133 DisableValidationForModuleKind::PCH; 134 CInvok->getPreprocessorOpts().Includes.clear(); 135 CInvok->getPreprocessorOpts().MacroIncludes.clear(); 136 CInvok->getPreprocessorOpts().Macros.clear(); 137 138 CInvok->getFrontendOpts().Inputs.clear(); 139 FrontendInputFile InputFile(includes[i], IK); 140 CInvok->getFrontendOpts().Inputs.push_back(InputFile); 141 142 TextDiagnosticPrinter *DiagClient = 143 new TextDiagnosticPrinter(llvm::errs(), new DiagnosticOptions()); 144 IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs()); 145 IntrusiveRefCntPtr<DiagnosticsEngine> Diags( 146 new DiagnosticsEngine(DiagID, &CI.getDiagnosticOpts(), DiagClient)); 147 148 std::unique_ptr<CompilerInstance> Clang( 149 new CompilerInstance(CI.getPCHContainerOperations())); 150 Clang->setInvocation(std::move(CInvok)); 151 Clang->setDiagnostics(Diags.get()); 152 Clang->setTarget(TargetInfo::CreateTargetInfo( 153 Clang->getDiagnostics(), Clang->getInvocation().TargetOpts)); 154 Clang->createFileManager(); 155 Clang->createSourceManager(Clang->getFileManager()); 156 Clang->createPreprocessor(TU_Prefix); 157 Clang->getDiagnosticClient().BeginSourceFile(Clang->getLangOpts(), 158 &Clang->getPreprocessor()); 159 Clang->createASTContext(); 160 161 auto Buffer = std::make_shared<PCHBuffer>(); 162 ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions; 163 auto consumer = std::make_unique<PCHGenerator>( 164 Clang->getPreprocessor(), Clang->getModuleCache(), "-", /*isysroot=*/"", 165 Buffer, Extensions, /*AllowASTWithErrors=*/true); 166 Clang->getASTContext().setASTMutationListener( 167 consumer->GetASTMutationListener()); 168 Clang->setASTConsumer(std::move(consumer)); 169 Clang->createSema(TU_Prefix, nullptr); 170 171 if (firstInclude) { 172 Preprocessor &PP = Clang->getPreprocessor(); 173 PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(), 174 PP.getLangOpts()); 175 } else { 176 assert(!SerialBufs.empty()); 177 SmallVector<std::unique_ptr<llvm::MemoryBuffer>, 4> Bufs; 178 // TODO: Pass through the existing MemoryBuffer instances instead of 179 // allocating new ones. 180 for (auto &SB : SerialBufs) 181 Bufs.push_back(llvm::MemoryBuffer::getMemBuffer(SB->getBuffer())); 182 std::string pchName = includes[i-1]; 183 llvm::raw_string_ostream os(pchName); 184 os << ".pch" << i-1; 185 serialBufNames.push_back(os.str()); 186 187 IntrusiveRefCntPtr<ASTReader> Reader; 188 Reader = createASTReader( 189 *Clang, pchName, Bufs, serialBufNames, 190 Clang->getASTConsumer().GetASTDeserializationListener()); 191 if (!Reader) 192 return nullptr; 193 Clang->setASTReader(Reader); 194 Clang->getASTContext().setExternalSource(Reader); 195 } 196 197 if (!Clang->InitializeSourceManager(InputFile)) 198 return nullptr; 199 200 ParseAST(Clang->getSema()); 201 Clang->getDiagnosticClient().EndSourceFile(); 202 assert(Buffer->IsComplete && "serialization did not complete"); 203 auto &serialAST = Buffer->Data; 204 SerialBufs.push_back(llvm::MemoryBuffer::getMemBufferCopy( 205 StringRef(serialAST.data(), serialAST.size()))); 206 serialAST.clear(); 207 CIs.push_back(std::move(Clang)); 208 } 209 210 assert(!SerialBufs.empty()); 211 std::string pchName = includes.back() + ".pch-final"; 212 serialBufNames.push_back(pchName); 213 Reader = createASTReader(CI, pchName, SerialBufs, serialBufNames); 214 if (!Reader) 215 return nullptr; 216 217 return IntrusiveRefCntPtr<ChainedIncludesSource>( 218 new ChainedIncludesSource(std::move(CIs), Reader)); 219 } 220
Indexes created Tue Feb 24 08:35:24 UTC 2026