lib/Frontend/ChainedIncludesSource.cpp

   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/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:
  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.
  42   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 {
  58   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:
  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 *
  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.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
 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().ImplicitPTHInclude.clear();
 133     CInvok->getPreprocessorOpts().DisablePCHValidation = true;
 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(CInvok.release());
 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<llvm::IntrusiveRefCntPtr<ModuleFileExtension>> Extensions;
 163     auto consumer = llvm::make_unique<PCHGenerator>(
 164         Clang->getPreprocessor(), "-", /*isysroot=*/"", Buffer,
 165         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->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     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 }