1 //===- ChainedIncludesSource.cpp - Chained PCHs in Memory -------*- 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 ChainedIncludesSource class, which converts headers
11 //  to chained PCHs in memory, mainly used for testing.
12 //
13 //===----------------------------------------------------------------------===//
14 
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/Parse/ParseAST.h"
21 #include "clang/Serialization/ASTReader.h"
22 #include "clang/Serialization/ASTWriter.h"
23 #include "llvm/Support/MemoryBuffer.h"
24 
25 using namespace clang;
26 
27 namespace {
28 class ChainedIncludesSource : public ExternalSemaSource {
29 public:
30   ~ChainedIncludesSource() override;
31 
32   ExternalSemaSource &getFinalReader() const { return *FinalReader; }
33 
34   std::vector<CompilerInstance *> CIs;
35   IntrusiveRefCntPtr<ExternalSemaSource> FinalReader;
36 
37 protected:
38   //===----------------------------------------------------------------------===//
39   // ExternalASTSource interface.
40   //===----------------------------------------------------------------------===//
41 
42   Decl *GetExternalDecl(uint32_t ID) override;
43   Selector GetExternalSelector(uint32_t ID) override;
44   uint32_t GetNumExternalSelectors() override;
45   Stmt *GetExternalDeclStmt(uint64_t Offset) override;
46   CXXCtorInitializer **GetExternalCXXCtorInitializers(uint64_t Offset) override;
47   CXXBaseSpecifier *GetExternalCXXBaseSpecifiers(uint64_t Offset) override;
48   bool FindExternalVisibleDeclsByName(const DeclContext *DC,
49                                       DeclarationName Name) override;
50   void
51   FindExternalLexicalDecls(const DeclContext *DC,
52                            llvm::function_ref<bool(Decl::Kind)> IsKindWeWant,
53                            SmallVectorImpl<Decl *> &Result) override;
54   void CompleteType(TagDecl *Tag) override;
55   void CompleteType(ObjCInterfaceDecl *Class) override;
56   void StartedDeserializing() override;
57   void FinishedDeserializing() override;
58   void StartTranslationUnit(ASTConsumer *Consumer) override;
59   void PrintStats() override;
60 
61   /// Return the amount of memory used by memory buffers, breaking down
62   /// by heap-backed versus mmap'ed memory.
63   void getMemoryBufferSizes(MemoryBufferSizes &sizes) const override;
64 
65   //===----------------------------------------------------------------------===//
66   // ExternalSemaSource interface.
67   //===----------------------------------------------------------------------===//
68 
69   void InitializeSema(Sema &S) override;
70   void ForgetSema() override;
71   void ReadMethodPool(Selector Sel) override;
72   bool LookupUnqualified(LookupResult &R, Scope *S) override;
73 };
74 }
75 
76 static ASTReader *
77 createASTReader(CompilerInstance &CI, StringRef pchFile,
78                 SmallVectorImpl<std::unique_ptr<llvm::MemoryBuffer>> &MemBufs,
79                 SmallVectorImpl<std::string> &bufNames,
80                 ASTDeserializationListener *deserialListener = nullptr) {
81   Preprocessor &PP = CI.getPreprocessor();
82   std::unique_ptr<ASTReader> Reader;
83   Reader.reset(new ASTReader(PP, CI.getASTContext(),
84                              CI.getPCHContainerReader(),
85                              /*isysroot=*/"", /*DisableValidation=*/true));
86   for (unsigned ti = 0; ti < bufNames.size(); ++ti) {
87     StringRef sr(bufNames[ti]);
88     Reader->addInMemoryBuffer(sr, std::move(MemBufs[ti]));
89   }
90   Reader->setDeserializationListener(deserialListener);
91   switch (Reader->ReadAST(pchFile, serialization::MK_PCH, SourceLocation(),
92                           ASTReader::ARR_None)) {
93   case ASTReader::Success:
94     // Set the predefines buffer as suggested by the PCH reader.
95     PP.setPredefines(Reader->getSuggestedPredefines());
96     return Reader.release();
97 
98   case ASTReader::Failure:
99   case ASTReader::Missing:
100   case ASTReader::OutOfDate:
101   case ASTReader::VersionMismatch:
102   case ASTReader::ConfigurationMismatch:
103   case ASTReader::HadErrors:
104     break;
105   }
106   return nullptr;
107 }
108 
109 ChainedIncludesSource::~ChainedIncludesSource() {
110   for (unsigned i = 0, e = CIs.size(); i != e; ++i)
111     delete CIs[i];
112 }
113 
114 IntrusiveRefCntPtr<ExternalSemaSource> clang::createChainedIncludesSource(
115     CompilerInstance &CI, IntrusiveRefCntPtr<ExternalSemaSource> &Reader) {
116 
117   std::vector<std::string> &includes = CI.getPreprocessorOpts().ChainedIncludes;
118   assert(!includes.empty() && "No '-chain-include' in options!");
119 
120   IntrusiveRefCntPtr<ChainedIncludesSource> source(new ChainedIncludesSource());
121   InputKind IK = CI.getFrontendOpts().Inputs[0].getKind();
122 
123   SmallVector<std::unique_ptr<llvm::MemoryBuffer>, 4> SerialBufs;
124   SmallVector<std::string, 4> serialBufNames;
125 
126   for (unsigned i = 0, e = includes.size(); i != e; ++i) {
127     bool firstInclude = (i == 0);
128     std::unique_ptr<CompilerInvocation> CInvok;
129     CInvok.reset(new CompilerInvocation(CI.getInvocation()));
130 
131     CInvok->getPreprocessorOpts().ChainedIncludes.clear();
132     CInvok->getPreprocessorOpts().ImplicitPCHInclude.clear();
133     CInvok->getPreprocessorOpts().ImplicitPTHInclude.clear();
134     CInvok->getPreprocessorOpts().DisablePCHValidation = true;
135     CInvok->getPreprocessorOpts().Includes.clear();
136     CInvok->getPreprocessorOpts().MacroIncludes.clear();
137     CInvok->getPreprocessorOpts().Macros.clear();
138 
139     CInvok->getFrontendOpts().Inputs.clear();
140     FrontendInputFile InputFile(includes[i], IK);
141     CInvok->getFrontendOpts().Inputs.push_back(InputFile);
142 
143     TextDiagnosticPrinter *DiagClient =
144       new TextDiagnosticPrinter(llvm::errs(), new DiagnosticOptions());
145     IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
146     IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
147         new DiagnosticsEngine(DiagID, &CI.getDiagnosticOpts(), DiagClient));
148 
149     std::unique_ptr<CompilerInstance> Clang(
150         new CompilerInstance(CI.getPCHContainerOperations()));
151     Clang->setInvocation(CInvok.release());
152     Clang->setDiagnostics(Diags.get());
153     Clang->setTarget(TargetInfo::CreateTargetInfo(
154         Clang->getDiagnostics(), Clang->getInvocation().TargetOpts));
155     Clang->createFileManager();
156     Clang->createSourceManager(Clang->getFileManager());
157     Clang->createPreprocessor(TU_Prefix);
158     Clang->getDiagnosticClient().BeginSourceFile(Clang->getLangOpts(),
159                                                  &Clang->getPreprocessor());
160     Clang->createASTContext();
161 
162     auto Buffer = std::make_shared<PCHBuffer>();
163     auto consumer = llvm::make_unique<PCHGenerator>(
164         Clang->getPreprocessor(), "-", nullptr, /*isysroot=*/"", Buffer);
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->setModuleManager(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     source->CIs.push_back(Clang.release());
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   source->FinalReader = Reader;
217   return source;
218 }
219 
220 //===----------------------------------------------------------------------===//
221 // ExternalASTSource interface.
222 //===----------------------------------------------------------------------===//
223 
224 Decl *ChainedIncludesSource::GetExternalDecl(uint32_t ID) {
225   return getFinalReader().GetExternalDecl(ID);
226 }
227 Selector ChainedIncludesSource::GetExternalSelector(uint32_t ID) {
228   return getFinalReader().GetExternalSelector(ID);
229 }
230 uint32_t ChainedIncludesSource::GetNumExternalSelectors() {
231   return getFinalReader().GetNumExternalSelectors();
232 }
233 Stmt *ChainedIncludesSource::GetExternalDeclStmt(uint64_t Offset) {
234   return getFinalReader().GetExternalDeclStmt(Offset);
235 }
236 CXXBaseSpecifier *
237 ChainedIncludesSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
238   return getFinalReader().GetExternalCXXBaseSpecifiers(Offset);
239 }
240 CXXCtorInitializer **
241 ChainedIncludesSource::GetExternalCXXCtorInitializers(uint64_t Offset) {
242   return getFinalReader().GetExternalCXXCtorInitializers(Offset);
243 }
244 bool
245 ChainedIncludesSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
246                                                       DeclarationName Name) {
247   return getFinalReader().FindExternalVisibleDeclsByName(DC, Name);
248 }
249 void ChainedIncludesSource::FindExternalLexicalDecls(
250     const DeclContext *DC, llvm::function_ref<bool(Decl::Kind)> IsKindWeWant,
251     SmallVectorImpl<Decl *> &Result) {
252   return getFinalReader().FindExternalLexicalDecls(DC, IsKindWeWant, Result);
253 }
254 void ChainedIncludesSource::CompleteType(TagDecl *Tag) {
255   return getFinalReader().CompleteType(Tag);
256 }
257 void ChainedIncludesSource::CompleteType(ObjCInterfaceDecl *Class) {
258   return getFinalReader().CompleteType(Class);
259 }
260 void ChainedIncludesSource::StartedDeserializing() {
261   return getFinalReader().StartedDeserializing();
262 }
263 void ChainedIncludesSource::FinishedDeserializing() {
264   return getFinalReader().FinishedDeserializing();
265 }
266 void ChainedIncludesSource::StartTranslationUnit(ASTConsumer *Consumer) {
267   return getFinalReader().StartTranslationUnit(Consumer);
268 }
269 void ChainedIncludesSource::PrintStats() {
270   return getFinalReader().PrintStats();
271 }
272 void ChainedIncludesSource::getMemoryBufferSizes(MemoryBufferSizes &sizes)const{
273   for (unsigned i = 0, e = CIs.size(); i != e; ++i) {
274     if (const ExternalASTSource *eSrc =
275         CIs[i]->getASTContext().getExternalSource()) {
276       eSrc->getMemoryBufferSizes(sizes);
277     }
278   }
279 
280   getFinalReader().getMemoryBufferSizes(sizes);
281 }
282 
283 void ChainedIncludesSource::InitializeSema(Sema &S) {
284   return getFinalReader().InitializeSema(S);
285 }
286 void ChainedIncludesSource::ForgetSema() {
287   return getFinalReader().ForgetSema();
288 }
289 void ChainedIncludesSource::ReadMethodPool(Selector Sel) {
290   getFinalReader().ReadMethodPool(Sel);
291 }
292 bool ChainedIncludesSource::LookupUnqualified(LookupResult &R, Scope *S) {
293   return getFinalReader().LookupUnqualified(R, S);
294 }
295 
296