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:
ChainedIncludesSourceImpl(std::vector<std::unique_ptr<CompilerInstance>> CIs)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.
getMemoryBufferSizes(MemoryBufferSizes & sizes) const42 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 {
ChainedIncludesSourceMembers__anonea9ec8030111::ChainedIncludesSourceMembers58 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:
ChainedIncludesSource(std::vector<std::unique_ptr<CompilerInstance>> CIs,IntrusiveRefCntPtr<ExternalSemaSource> FinalReader)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 *
createASTReader(CompilerInstance & CI,StringRef pchFile,SmallVectorImpl<std::unique_ptr<llvm::MemoryBuffer>> & MemBufs,SmallVectorImpl<std::string> & bufNames,ASTDeserializationListener * deserialListener=nullptr)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
createChainedIncludesSource(CompilerInstance & CI,IntrusiveRefCntPtr<ExternalSemaSource> & Reader)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