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__anon5597dd6d0111::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(PP, CI.getModuleCache(), &CI.getASTContext(),
87 CI.getPCHContainerReader(),
88 /*Extensions=*/{},
89 /*isysroot=*/"", /*DisableValidation=*/true));
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().DisablePCHValidation = true;
133 CInvok->getPreprocessorOpts().Includes.clear();
134 CInvok->getPreprocessorOpts().MacroIncludes.clear();
135 CInvok->getPreprocessorOpts().Macros.clear();
136
137 CInvok->getFrontendOpts().Inputs.clear();
138 FrontendInputFile InputFile(includes[i], IK);
139 CInvok->getFrontendOpts().Inputs.push_back(InputFile);
140
141 TextDiagnosticPrinter *DiagClient =
142 new TextDiagnosticPrinter(llvm::errs(), new DiagnosticOptions());
143 IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
144 IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
145 new DiagnosticsEngine(DiagID, &CI.getDiagnosticOpts(), DiagClient));
146
147 std::unique_ptr<CompilerInstance> Clang(
148 new CompilerInstance(CI.getPCHContainerOperations()));
149 Clang->setInvocation(std::move(CInvok));
150 Clang->setDiagnostics(Diags.get());
151 Clang->setTarget(TargetInfo::CreateTargetInfo(
152 Clang->getDiagnostics(), Clang->getInvocation().TargetOpts));
153 Clang->createFileManager();
154 Clang->createSourceManager(Clang->getFileManager());
155 Clang->createPreprocessor(TU_Prefix);
156 Clang->getDiagnosticClient().BeginSourceFile(Clang->getLangOpts(),
157 &Clang->getPreprocessor());
158 Clang->createASTContext();
159
160 auto Buffer = std::make_shared<PCHBuffer>();
161 ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions;
162 auto consumer = std::make_unique<PCHGenerator>(
163 Clang->getPreprocessor(), Clang->getModuleCache(), "-", /*isysroot=*/"",
164 Buffer, Extensions, /*AllowASTWithErrors=*/true);
165 Clang->getASTContext().setASTMutationListener(
166 consumer->GetASTMutationListener());
167 Clang->setASTConsumer(std::move(consumer));
168 Clang->createSema(TU_Prefix, nullptr);
169
170 if (firstInclude) {
171 Preprocessor &PP = Clang->getPreprocessor();
172 PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
173 PP.getLangOpts());
174 } else {
175 assert(!SerialBufs.empty());
176 SmallVector<std::unique_ptr<llvm::MemoryBuffer>, 4> Bufs;
177 // TODO: Pass through the existing MemoryBuffer instances instead of
178 // allocating new ones.
179 for (auto &SB : SerialBufs)
180 Bufs.push_back(llvm::MemoryBuffer::getMemBuffer(SB->getBuffer()));
181 std::string pchName = includes[i-1];
182 llvm::raw_string_ostream os(pchName);
183 os << ".pch" << i-1;
184 serialBufNames.push_back(os.str());
185
186 IntrusiveRefCntPtr<ASTReader> Reader;
187 Reader = createASTReader(
188 *Clang, pchName, Bufs, serialBufNames,
189 Clang->getASTConsumer().GetASTDeserializationListener());
190 if (!Reader)
191 return nullptr;
192 Clang->setASTReader(Reader);
193 Clang->getASTContext().setExternalSource(Reader);
194 }
195
196 if (!Clang->InitializeSourceManager(InputFile))
197 return nullptr;
198
199 ParseAST(Clang->getSema());
200 Clang->getDiagnosticClient().EndSourceFile();
201 assert(Buffer->IsComplete && "serialization did not complete");
202 auto &serialAST = Buffer->Data;
203 SerialBufs.push_back(llvm::MemoryBuffer::getMemBufferCopy(
204 StringRef(serialAST.data(), serialAST.size())));
205 serialAST.clear();
206 CIs.push_back(std::move(Clang));
207 }
208
209 assert(!SerialBufs.empty());
210 std::string pchName = includes.back() + ".pch-final";
211 serialBufNames.push_back(pchName);
212 Reader = createASTReader(CI, pchName, SerialBufs, serialBufNames);
213 if (!Reader)
214 return nullptr;
215
216 return IntrusiveRefCntPtr<ChainedIncludesSource>(
217 new ChainedIncludesSource(std::move(CIs), Reader));
218 }
219