Index: include/clang-c/Index.h =================================================================== --- include/clang-c/Index.h +++ include/clang-c/Index.h @@ -1200,7 +1200,15 @@ * included into the set of code completions returned from this translation * unit. */ - CXTranslationUnit_IncludeBriefCommentsInCodeCompletion = 0x80 + CXTranslationUnit_IncludeBriefCommentsInCodeCompletion = 0x80, + + /** + * \brief Used to indicate that the precompiled preamble should be created on + * the first parse. Otherwise it will be created on the first reparse. This + * trades runtime on the first parse (serializing the preamble takes time) for + * reduced runtime on the second parse (can now reuse the preamble). + */ + CXTranslationUnit_CreatePreambleOnFirstParse = 0x100 }; /** Index: include/clang/Frontend/ASTUnit.h =================================================================== --- include/clang/Frontend/ASTUnit.h +++ include/clang/Frontend/ASTUnit.h @@ -737,14 +737,15 @@ /// \brief Helper function for \c LoadFromCompilerInvocation() and /// \c LoadFromCommandLine(), which loads an AST from a compiler invocation. /// - /// \param PrecompilePreamble Whether to precompile the preamble of this - /// translation unit, to improve the performance of reparsing. + /// \param PrecompilePreambleAfterNParses After how many parses the preamble + /// of this translation unit should be precompiled, to improve the performance + /// of reparsing. Set to zero to disable preambles. /// /// \returns \c true if a catastrophic failure occurred (which means that the /// \c ASTUnit itself is invalid), or \c false otherwise. bool LoadFromCompilerInvocation( std::shared_ptr PCHContainerOps, - bool PrecompilePreamble); + unsigned PrecompilePreambleAfterNParses); public: @@ -783,7 +784,8 @@ ASTFrontendAction *Action = nullptr, ASTUnit *Unit = nullptr, bool Persistent = true, StringRef ResourceFilesPath = StringRef(), bool OnlyLocalDecls = false, bool CaptureDiagnostics = false, - bool PrecompilePreamble = false, bool CacheCodeCompletionResults = false, + unsigned PrecompilePreambleAfterNParses = 0, + bool CacheCodeCompletionResults = false, bool IncludeBriefCommentsInCodeCompletion = false, bool UserFilesAreVolatile = false, std::unique_ptr *ErrAST = nullptr); @@ -807,7 +809,8 @@ std::shared_ptr PCHContainerOps, IntrusiveRefCntPtr Diags, FileManager *FileMgr, bool OnlyLocalDecls = false, bool CaptureDiagnostics = false, - bool PrecompilePreamble = false, TranslationUnitKind TUKind = TU_Complete, + unsigned PrecompilePreambleAfterNParses = 0, + TranslationUnitKind TUKind = TU_Complete, bool CacheCodeCompletionResults = false, bool IncludeBriefCommentsInCodeCompletion = false, bool UserFilesAreVolatile = false); @@ -842,7 +845,8 @@ bool OnlyLocalDecls = false, bool CaptureDiagnostics = false, ArrayRef RemappedFiles = None, bool RemappedFilesKeepOriginalName = true, - bool PrecompilePreamble = false, TranslationUnitKind TUKind = TU_Complete, + unsigned PrecompilePreambleAfterNParses = 0, + TranslationUnitKind TUKind = TU_Complete, bool CacheCodeCompletionResults = false, bool IncludeBriefCommentsInCodeCompletion = false, bool AllowPCHWithCompilerErrors = false, bool SkipFunctionBodies = false, Index: lib/Frontend/ASTUnit.cpp =================================================================== --- lib/Frontend/ASTUnit.cpp +++ lib/Frontend/ASTUnit.cpp @@ -1725,9 +1725,10 @@ std::shared_ptr PCHContainerOps, IntrusiveRefCntPtr Diags, ASTFrontendAction *Action, ASTUnit *Unit, bool Persistent, StringRef ResourceFilesPath, - bool OnlyLocalDecls, bool CaptureDiagnostics, bool PrecompilePreamble, - bool CacheCodeCompletionResults, bool IncludeBriefCommentsInCodeCompletion, - bool UserFilesAreVolatile, std::unique_ptr *ErrAST) { + bool OnlyLocalDecls, bool CaptureDiagnostics, + unsigned PrecompilePreambleAfterNParses, bool CacheCodeCompletionResults, + bool IncludeBriefCommentsInCodeCompletion, bool UserFilesAreVolatile, + std::unique_ptr *ErrAST) { assert(CI && "A CompilerInvocation is required"); std::unique_ptr OwnAST; @@ -1746,8 +1747,8 @@ } AST->OnlyLocalDecls = OnlyLocalDecls; AST->CaptureDiagnostics = CaptureDiagnostics; - if (PrecompilePreamble) - AST->PreambleRebuildCounter = 2; + if (PrecompilePreambleAfterNParses > 0) + AST->PreambleRebuildCounter = PrecompilePreambleAfterNParses; AST->TUKind = Action ? Action->getTranslationUnitKind() : TU_Complete; AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults; AST->IncludeBriefCommentsInCodeCompletion @@ -1864,7 +1865,7 @@ bool ASTUnit::LoadFromCompilerInvocation( std::shared_ptr PCHContainerOps, - bool PrecompilePreamble) { + unsigned PrecompilePreambleAfterNParses) { if (!Invocation) return true; @@ -1874,8 +1875,8 @@ ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts()); std::unique_ptr OverrideMainBuffer; - if (PrecompilePreamble) { - PreambleRebuildCounter = 2; + if (PrecompilePreambleAfterNParses > 0) { + PreambleRebuildCounter = PrecompilePreambleAfterNParses; OverrideMainBuffer = getMainBufferWithPrecompiledPreamble(PCHContainerOps, *Invocation); } @@ -1894,9 +1895,10 @@ CompilerInvocation *CI, std::shared_ptr PCHContainerOps, IntrusiveRefCntPtr Diags, FileManager *FileMgr, - bool OnlyLocalDecls, bool CaptureDiagnostics, bool PrecompilePreamble, - TranslationUnitKind TUKind, bool CacheCodeCompletionResults, - bool IncludeBriefCommentsInCodeCompletion, bool UserFilesAreVolatile) { + bool OnlyLocalDecls, bool CaptureDiagnostics, + unsigned PrecompilePreambleAfterNParses, TranslationUnitKind TUKind, + bool CacheCodeCompletionResults, bool IncludeBriefCommentsInCodeCompletion, + bool UserFilesAreVolatile) { // Create the AST unit. std::unique_ptr AST(new ASTUnit(false)); ConfigureDiags(Diags, *AST, CaptureDiagnostics); @@ -1919,7 +1921,8 @@ llvm::CrashRecoveryContextReleaseRefCleanup > DiagCleanup(Diags.get()); - if (AST->LoadFromCompilerInvocation(PCHContainerOps, PrecompilePreamble)) + if (AST->LoadFromCompilerInvocation(PCHContainerOps, + PrecompilePreambleAfterNParses)) return nullptr; return AST; } @@ -1930,12 +1933,11 @@ IntrusiveRefCntPtr Diags, StringRef ResourceFilesPath, bool OnlyLocalDecls, bool CaptureDiagnostics, ArrayRef RemappedFiles, bool RemappedFilesKeepOriginalName, - bool PrecompilePreamble, TranslationUnitKind TUKind, + unsigned PrecompilePreambleAfterNParses, TranslationUnitKind TUKind, bool CacheCodeCompletionResults, bool IncludeBriefCommentsInCodeCompletion, bool AllowPCHWithCompilerErrors, bool SkipFunctionBodies, bool UserFilesAreVolatile, bool ForSerialization, - llvm::Optional ModuleFormat, - std::unique_ptr *ErrAST) { + llvm::Optional ModuleFormat, std::unique_ptr *ErrAST) { assert(Diags.get() && "no DiagnosticsEngine was provided"); SmallVector StoredDiagnostics; @@ -2002,7 +2004,8 @@ llvm::CrashRecoveryContextCleanupRegistrar ASTUnitCleanup(AST.get()); - if (AST->LoadFromCompilerInvocation(PCHContainerOps, PrecompilePreamble)) { + if (AST->LoadFromCompilerInvocation(PCHContainerOps, + PrecompilePreambleAfterNParses)) { // Some error occurred, if caller wants to examine diagnostics, pass it the // ASTUnit. if (ErrAST) { Index: tools/libclang/CIndex.cpp =================================================================== --- tools/libclang/CIndex.cpp +++ tools/libclang/CIndex.cpp @@ -3073,6 +3073,8 @@ setThreadBackgroundPriority(); bool PrecompilePreamble = options & CXTranslationUnit_PrecompiledPreamble; + bool CreatePreambleOnFirstParse = + options & CXTranslationUnit_CreatePreambleOnFirstParse; // FIXME: Add a flag for modules. TranslationUnitKind TUKind = (options & CXTranslationUnit_Incomplete)? TU_Prefix : TU_Complete; @@ -3147,13 +3149,18 @@ unsigned NumErrors = Diags->getClient()->getNumErrors(); std::unique_ptr ErrUnit; + // Unless the user specified that they want the preamble on the first parse + // set it up to be created on the first reparse. This makes the first parse + // faster, trading for a slower (first) reparse. + unsigned PrecompilePreambleAfterNParses = + !PrecompilePreamble ? 0 : 2 - CreatePreambleOnFirstParse; std::unique_ptr Unit(ASTUnit::LoadFromCommandLine( Args->data(), Args->data() + Args->size(), CXXIdx->getPCHContainerOperations(), Diags, CXXIdx->getClangResourcesPath(), CXXIdx->getOnlyLocalDecls(), /*CaptureDiagnostics=*/true, *RemappedFiles.get(), - /*RemappedFilesKeepOriginalName=*/true, PrecompilePreamble, TUKind, - CacheCodeCompletionResults, IncludeBriefCommentsInCodeCompletion, + /*RemappedFilesKeepOriginalName=*/true, PrecompilePreambleAfterNParses, + TUKind, CacheCodeCompletionResults, IncludeBriefCommentsInCodeCompletion, /*AllowPCHWithCompilerErrors=*/true, SkipFunctionBodies, /*UserFilesAreVolatile=*/true, ForSerialization, CXXIdx->getPCHContainerOperations()->getRawReader().getFormat(), Index: tools/libclang/Indexing.cpp =================================================================== --- tools/libclang/Indexing.cpp +++ tools/libclang/Indexing.cpp @@ -601,6 +601,7 @@ bool Persistent = requestedToGetTU; bool OnlyLocalDecls = false; bool PrecompilePreamble = false; + bool CreatePreambleOnFirstParse = false; bool CacheCodeCompletionResults = false; PreprocessorOptions &PPOpts = CInvok->getPreprocessorOpts(); PPOpts.AllowPCHWithCompilerErrors = true; @@ -608,6 +609,8 @@ if (requestedToGetTU) { OnlyLocalDecls = CXXIdx->getOnlyLocalDecls(); PrecompilePreamble = TU_options & CXTranslationUnit_PrecompiledPreamble; + CreatePreambleOnFirstParse = + TU_options & CXTranslationUnit_CreatePreambleOnFirstParse; // FIXME: Add a flag for modules. CacheCodeCompletionResults = TU_options & CXTranslationUnit_CacheCompletionResults; @@ -620,11 +623,16 @@ if (!requestedToGetTU && !CInvok->getLangOpts()->Modules) PPOpts.DetailedRecord = false; + // Unless the user specified that they want the preamble on the first parse + // set it up to be created on the first reparse. This makes the first parse + // faster, trading for a slower (first) reparse. + unsigned PrecompilePreambleAfterNParses = + !PrecompilePreamble ? 0 : 2 - CreatePreambleOnFirstParse; DiagnosticErrorTrap DiagTrap(*Diags); bool Success = ASTUnit::LoadFromCompilerInvocationAction( CInvok.get(), CXXIdx->getPCHContainerOperations(), Diags, IndexAction.get(), Unit, Persistent, CXXIdx->getClangResourcesPath(), - OnlyLocalDecls, CaptureDiagnostics, PrecompilePreamble, + OnlyLocalDecls, CaptureDiagnostics, PrecompilePreambleAfterNParses, CacheCodeCompletionResults, /*IncludeBriefCommentsInCodeCompletion=*/false, /*UserFilesAreVolatile=*/true);