1 //===- ChainedIncludesSource.cpp - Chained PCHs in Memory -------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 // This file defines the ChainedIncludesSource class, which converts headers
10 // to chained PCHs in memory, mainly used for testing.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Basic/TargetInfo.h"
15 #include "clang/Frontend/ASTUnit.h"
16 #include "clang/Frontend/CompilerInstance.h"
17 #include "clang/Frontend/TextDiagnosticPrinter.h"
18 #include "clang/Lex/Preprocessor.h"
19 #include "clang/Lex/PreprocessorOptions.h"
20 #include "clang/Parse/ParseAST.h"
21 #include "clang/Sema/MultiplexExternalSemaSource.h"
22 #include "clang/Serialization/ASTReader.h"
23 #include "clang/Serialization/ASTWriter.h"
24 #include "llvm/Support/MemoryBuffer.h"
26 using namespace clang;
29 class ChainedIncludesSourceImpl : public ExternalSemaSource {
31 ChainedIncludesSourceImpl(std::vector<std::unique_ptr<CompilerInstance>> CIs)
32 : CIs(std::move(CIs)) {}
35 //===----------------------------------------------------------------------===//
36 // ExternalASTSource interface.
37 //===----------------------------------------------------------------------===//
39 /// Return the amount of memory used by memory buffers, breaking down
40 /// by heap-backed versus mmap'ed memory.
41 void getMemoryBufferSizes(MemoryBufferSizes &sizes) const override {
42 for (unsigned i = 0, e = CIs.size(); i != e; ++i) {
43 if (const ExternalASTSource *eSrc =
44 CIs[i]->getASTContext().getExternalSource()) {
45 eSrc->getMemoryBufferSizes(sizes);
51 std::vector<std::unique_ptr<CompilerInstance>> CIs;
54 /// Members of ChainedIncludesSource, factored out so we can initialize
55 /// them before we initialize the ExternalSemaSource base class.
56 struct ChainedIncludesSourceMembers {
57 ChainedIncludesSourceMembers(
58 std::vector<std::unique_ptr<CompilerInstance>> CIs,
59 IntrusiveRefCntPtr<ExternalSemaSource> FinalReader)
60 : Impl(std::move(CIs)), FinalReader(std::move(FinalReader)) {}
61 ChainedIncludesSourceImpl Impl;
62 IntrusiveRefCntPtr<ExternalSemaSource> FinalReader;
65 /// Use MultiplexExternalSemaSource to dispatch all ExternalSemaSource
66 /// calls to the final reader.
67 class ChainedIncludesSource
68 : private ChainedIncludesSourceMembers,
69 public MultiplexExternalSemaSource {
71 ChainedIncludesSource(std::vector<std::unique_ptr<CompilerInstance>> CIs,
72 IntrusiveRefCntPtr<ExternalSemaSource> FinalReader)
73 : ChainedIncludesSourceMembers(std::move(CIs), std::move(FinalReader)),
74 MultiplexExternalSemaSource(Impl, *this->FinalReader) {}
79 createASTReader(CompilerInstance &CI, StringRef pchFile,
80 SmallVectorImpl<std::unique_ptr<llvm::MemoryBuffer>> &MemBufs,
81 SmallVectorImpl<std::string> &bufNames,
82 ASTDeserializationListener *deserialListener = nullptr) {
83 Preprocessor &PP = CI.getPreprocessor();
84 std::unique_ptr<ASTReader> Reader;
85 Reader.reset(new ASTReader(PP, CI.getModuleCache(), &CI.getASTContext(),
86 CI.getPCHContainerReader(),
88 /*isysroot=*/"", /*DisableValidation=*/true));
89 for (unsigned ti = 0; ti < bufNames.size(); ++ti) {
90 StringRef sr(bufNames[ti]);
91 Reader->addInMemoryBuffer(sr, std::move(MemBufs[ti]));
93 Reader->setDeserializationListener(deserialListener);
94 switch (Reader->ReadAST(pchFile, serialization::MK_PCH, SourceLocation(),
95 ASTReader::ARR_None)) {
96 case ASTReader::Success:
97 // Set the predefines buffer as suggested by the PCH reader.
98 PP.setPredefines(Reader->getSuggestedPredefines());
99 return Reader.release();
101 case ASTReader::Failure:
102 case ASTReader::Missing:
103 case ASTReader::OutOfDate:
104 case ASTReader::VersionMismatch:
105 case ASTReader::ConfigurationMismatch:
106 case ASTReader::HadErrors:
112 IntrusiveRefCntPtr<ExternalSemaSource> clang::createChainedIncludesSource(
113 CompilerInstance &CI, IntrusiveRefCntPtr<ExternalSemaSource> &Reader) {
115 std::vector<std::string> &includes = CI.getPreprocessorOpts().ChainedIncludes;
116 assert(!includes.empty() && "No '-chain-include' in options!");
118 std::vector<std::unique_ptr<CompilerInstance>> CIs;
119 InputKind IK = CI.getFrontendOpts().Inputs[0].getKind();
121 SmallVector<std::unique_ptr<llvm::MemoryBuffer>, 4> SerialBufs;
122 SmallVector<std::string, 4> serialBufNames;
124 for (unsigned i = 0, e = includes.size(); i != e; ++i) {
125 bool firstInclude = (i == 0);
126 std::unique_ptr<CompilerInvocation> CInvok;
127 CInvok.reset(new CompilerInvocation(CI.getInvocation()));
129 CInvok->getPreprocessorOpts().ChainedIncludes.clear();
130 CInvok->getPreprocessorOpts().ImplicitPCHInclude.clear();
131 CInvok->getPreprocessorOpts().DisablePCHValidation = true;
132 CInvok->getPreprocessorOpts().Includes.clear();
133 CInvok->getPreprocessorOpts().MacroIncludes.clear();
134 CInvok->getPreprocessorOpts().Macros.clear();
136 CInvok->getFrontendOpts().Inputs.clear();
137 FrontendInputFile InputFile(includes[i], IK);
138 CInvok->getFrontendOpts().Inputs.push_back(InputFile);
140 TextDiagnosticPrinter *DiagClient =
141 new TextDiagnosticPrinter(llvm::errs(), new DiagnosticOptions());
142 IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
143 IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
144 new DiagnosticsEngine(DiagID, &CI.getDiagnosticOpts(), DiagClient));
146 std::unique_ptr<CompilerInstance> Clang(
147 new CompilerInstance(CI.getPCHContainerOperations()));
148 Clang->setInvocation(std::move(CInvok));
149 Clang->setDiagnostics(Diags.get());
150 Clang->setTarget(TargetInfo::CreateTargetInfo(
151 Clang->getDiagnostics(), Clang->getInvocation().TargetOpts));
152 Clang->createFileManager();
153 Clang->createSourceManager(Clang->getFileManager());
154 Clang->createPreprocessor(TU_Prefix);
155 Clang->getDiagnosticClient().BeginSourceFile(Clang->getLangOpts(),
156 &Clang->getPreprocessor());
157 Clang->createASTContext();
159 auto Buffer = std::make_shared<PCHBuffer>();
160 ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions;
161 auto consumer = llvm::make_unique<PCHGenerator>(
162 Clang->getPreprocessor(), Clang->getModuleCache(), "-", /*isysroot=*/"",
163 Buffer, Extensions, /*AllowASTWithErrors=*/true);
164 Clang->getASTContext().setASTMutationListener(
165 consumer->GetASTMutationListener());
166 Clang->setASTConsumer(std::move(consumer));
167 Clang->createSema(TU_Prefix, nullptr);
170 Preprocessor &PP = Clang->getPreprocessor();
171 PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
174 assert(!SerialBufs.empty());
175 SmallVector<std::unique_ptr<llvm::MemoryBuffer>, 4> Bufs;
176 // TODO: Pass through the existing MemoryBuffer instances instead of
177 // allocating new ones.
178 for (auto &SB : SerialBufs)
179 Bufs.push_back(llvm::MemoryBuffer::getMemBuffer(SB->getBuffer()));
180 std::string pchName = includes[i-1];
181 llvm::raw_string_ostream os(pchName);
183 serialBufNames.push_back(os.str());
185 IntrusiveRefCntPtr<ASTReader> Reader;
186 Reader = createASTReader(
187 *Clang, pchName, Bufs, serialBufNames,
188 Clang->getASTConsumer().GetASTDeserializationListener());
191 Clang->setModuleManager(Reader);
192 Clang->getASTContext().setExternalSource(Reader);
195 if (!Clang->InitializeSourceManager(InputFile))
198 ParseAST(Clang->getSema());
199 Clang->getDiagnosticClient().EndSourceFile();
200 assert(Buffer->IsComplete && "serialization did not complete");
201 auto &serialAST = Buffer->Data;
202 SerialBufs.push_back(llvm::MemoryBuffer::getMemBufferCopy(
203 StringRef(serialAST.data(), serialAST.size())));
205 CIs.push_back(std::move(Clang));
208 assert(!SerialBufs.empty());
209 std::string pchName = includes.back() + ".pch-final";
210 serialBufNames.push_back(pchName);
211 Reader = createASTReader(CI, pchName, SerialBufs, serialBufNames);
215 return IntrusiveRefCntPtr<ChainedIncludesSource>(
216 new ChainedIncludesSource(std::move(CIs), Reader));