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   virtual ~ChainedIncludesSource();
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   CXXBaseSpecifier *GetExternalCXXBaseSpecifiers(uint64_t Offset) override;
47   bool FindExternalVisibleDeclsByName(const DeclContext *DC,
48                                       DeclarationName Name) override;
49   ExternalLoadResult
50   FindExternalLexicalDecls(const DeclContext *DC,
51                            bool (*isKindWeWant)(Decl::Kind),
52                            SmallVectorImpl<Decl *> &Result) override;
53   void CompleteType(TagDecl *Tag) override;
54   void CompleteType(ObjCInterfaceDecl *Class) override;
55   void StartedDeserializing() override;
56   void FinishedDeserializing() override;
57   void StartTranslationUnit(ASTConsumer *Consumer) override;
58   void PrintStats() override;
59 
60   /// Return the amount of memory used by memory buffers, breaking down
61   /// by heap-backed versus mmap'ed memory.
62   void getMemoryBufferSizes(MemoryBufferSizes &sizes) const override;
63 
64   //===----------------------------------------------------------------------===//
65   // ExternalSemaSource interface.
66   //===----------------------------------------------------------------------===//
67 
68   void InitializeSema(Sema &S) override;
69   void ForgetSema() override;
70   void ReadMethodPool(Selector Sel) override;
71   bool LookupUnqualified(LookupResult &R, Scope *S) override;
72 };
73 }
74 
75 static ASTReader *
76 createASTReader(CompilerInstance &CI, StringRef pchFile,
77                 SmallVectorImpl<std::unique_ptr<llvm::MemoryBuffer>> &MemBufs,
78                 SmallVectorImpl<std::string> &bufNames,
79                 ASTDeserializationListener *deserialListener = nullptr) {
80   Preprocessor &PP = CI.getPreprocessor();
81   std::unique_ptr<ASTReader> Reader;
82   Reader.reset(new ASTReader(PP, CI.getASTContext(), /*isysroot=*/"",
83                              /*DisableValidation=*/true));
84   for (unsigned ti = 0; ti < bufNames.size(); ++ti) {
85     StringRef sr(bufNames[ti]);
86     Reader->addInMemoryBuffer(sr, std::move(MemBufs[ti]));
87   }
88   Reader->setDeserializationListener(deserialListener);
89   switch (Reader->ReadAST(pchFile, serialization::MK_PCH, SourceLocation(),
90                           ASTReader::ARR_None)) {
91   case ASTReader::Success:
92     // Set the predefines buffer as suggested by the PCH reader.
93     PP.setPredefines(Reader->getSuggestedPredefines());
94     return Reader.release();
95 
96   case ASTReader::Failure:
97   case ASTReader::Missing:
98   case ASTReader::OutOfDate:
99   case ASTReader::VersionMismatch:
100   case ASTReader::ConfigurationMismatch:
101   case ASTReader::HadErrors:
102     break;
103   }
104   return nullptr;
105 }
106 
107 ChainedIncludesSource::~ChainedIncludesSource() {
108   for (unsigned i = 0, e = CIs.size(); i != e; ++i)
109     delete CIs[i];
110 }
111 
112 IntrusiveRefCntPtr<ExternalSemaSource> clang::createChainedIncludesSource(
113     CompilerInstance &CI, IntrusiveRefCntPtr<ExternalSemaSource> &Reader) {
114 
115   std::vector<std::string> &includes = CI.getPreprocessorOpts().ChainedIncludes;
116   assert(!includes.empty() && "No '-chain-include' in options!");
117 
118   IntrusiveRefCntPtr<ChainedIncludesSource> source(new ChainedIncludesSource());
119   InputKind IK = CI.getFrontendOpts().Inputs[0].getKind();
120 
121   SmallVector<std::unique_ptr<llvm::MemoryBuffer>, 4> SerialBufs;
122   SmallVector<std::string, 4> serialBufNames;
123 
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()));
128 
129     CInvok->getPreprocessorOpts().ChainedIncludes.clear();
130     CInvok->getPreprocessorOpts().ImplicitPCHInclude.clear();
131     CInvok->getPreprocessorOpts().ImplicitPTHInclude.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(new CompilerInstance());
148     Clang->setInvocation(CInvok.release());
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();
158 
159     auto consumer = llvm::make_unique<PCHGenerator>(Clang->getPreprocessor(),
160                                        "-", nullptr, /*isysroot=*/"");
161     SmallVectorImpl<char> *serialAST;
162     consumer->RegisterSerializationFinishedCallback(
163       [&](SmallVectorImpl<char> *Buf){
164         serialAST = Buf;
165       });
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->setModuleManager(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     SerialBufs.push_back(llvm::MemoryBuffer::
203         getMemBufferCopy(StringRef(serialAST->data(), serialAST->size())));
204     serialAST->clear();
205     source->CIs.push_back(Clang.release());
206   }
207 
208   assert(!SerialBufs.empty());
209   std::string pchName = includes.back() + ".pch-final";
210   serialBufNames.push_back(pchName);
211   Reader = createASTReader(CI, pchName, SerialBufs, serialBufNames);
212   if (!Reader)
213     return nullptr;
214 
215   source->FinalReader = Reader;
216   return source;
217 }
218 
219 //===----------------------------------------------------------------------===//
220 // ExternalASTSource interface.
221 //===----------------------------------------------------------------------===//
222 
223 Decl *ChainedIncludesSource::GetExternalDecl(uint32_t ID) {
224   return getFinalReader().GetExternalDecl(ID);
225 }
226 Selector ChainedIncludesSource::GetExternalSelector(uint32_t ID) {
227   return getFinalReader().GetExternalSelector(ID);
228 }
229 uint32_t ChainedIncludesSource::GetNumExternalSelectors() {
230   return getFinalReader().GetNumExternalSelectors();
231 }
232 Stmt *ChainedIncludesSource::GetExternalDeclStmt(uint64_t Offset) {
233   return getFinalReader().GetExternalDeclStmt(Offset);
234 }
235 CXXBaseSpecifier *
236 ChainedIncludesSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
237   return getFinalReader().GetExternalCXXBaseSpecifiers(Offset);
238 }
239 bool
240 ChainedIncludesSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
241                                                       DeclarationName Name) {
242   return getFinalReader().FindExternalVisibleDeclsByName(DC, Name);
243 }
244 ExternalLoadResult
245 ChainedIncludesSource::FindExternalLexicalDecls(const DeclContext *DC,
246                                       bool (*isKindWeWant)(Decl::Kind),
247                                       SmallVectorImpl<Decl*> &Result) {
248   return getFinalReader().FindExternalLexicalDecls(DC, isKindWeWant, Result);
249 }
250 void ChainedIncludesSource::CompleteType(TagDecl *Tag) {
251   return getFinalReader().CompleteType(Tag);
252 }
253 void ChainedIncludesSource::CompleteType(ObjCInterfaceDecl *Class) {
254   return getFinalReader().CompleteType(Class);
255 }
256 void ChainedIncludesSource::StartedDeserializing() {
257   return getFinalReader().StartedDeserializing();
258 }
259 void ChainedIncludesSource::FinishedDeserializing() {
260   return getFinalReader().FinishedDeserializing();
261 }
262 void ChainedIncludesSource::StartTranslationUnit(ASTConsumer *Consumer) {
263   return getFinalReader().StartTranslationUnit(Consumer);
264 }
265 void ChainedIncludesSource::PrintStats() {
266   return getFinalReader().PrintStats();
267 }
268 void ChainedIncludesSource::getMemoryBufferSizes(MemoryBufferSizes &sizes)const{
269   for (unsigned i = 0, e = CIs.size(); i != e; ++i) {
270     if (const ExternalASTSource *eSrc =
271         CIs[i]->getASTContext().getExternalSource()) {
272       eSrc->getMemoryBufferSizes(sizes);
273     }
274   }
275 
276   getFinalReader().getMemoryBufferSizes(sizes);
277 }
278 
279 void ChainedIncludesSource::InitializeSema(Sema &S) {
280   return getFinalReader().InitializeSema(S);
281 }
282 void ChainedIncludesSource::ForgetSema() {
283   return getFinalReader().ForgetSema();
284 }
285 void ChainedIncludesSource::ReadMethodPool(Selector Sel) {
286   getFinalReader().ReadMethodPool(Sel);
287 }
288 bool ChainedIncludesSource::LookupUnqualified(LookupResult &R, Scope *S) {
289   return getFinalReader().LookupUnqualified(R, S);
290 }
291 
292