Author: ibiryukov Date: Mon Jul 9 04:33:31 2018 New Revision: 336540 URL: http://llvm.org/viewvc/llvm-project?rev=336540&view=rev Log: [clangd] Do not write comments into Preamble PCH
Summary: To avoid wasting time deserializing them on code completion and further reparses. We do not use the comments anyway, because we cannot rely on the file contents staying the same for reparses that reuse the prebuilt preamble PCH. Reviewers: sammccall Reviewed By: sammccall Subscribers: ioeric, MaskRay, jkorous, cfe-commits Differential Revision: https://reviews.llvm.org/D48943 Modified: clang-tools-extra/trunk/clangd/ClangdUnit.cpp clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp Modified: clang-tools-extra/trunk/clangd/ClangdUnit.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clangd/ClangdUnit.cpp?rev=336540&r1=336539&r2=336540&view=diff ============================================================================== --- clang-tools-extra/trunk/clangd/ClangdUnit.cpp (original) +++ clang-tools-extra/trunk/clangd/ClangdUnit.cpp Mon Jul 9 04:33:31 2018 @@ -24,6 +24,7 @@ #include "clang/Lex/Lexer.h" #include "clang/Lex/MacroInfo.h" #include "clang/Lex/Preprocessor.h" +#include "clang/Lex/PreprocessorOptions.h" #include "clang/Sema/Sema.h" #include "clang/Serialization/ASTWriter.h" #include "clang/Tooling/CompilationDatabase.h" @@ -323,6 +324,9 @@ std::shared_ptr<const PreambleData> clan // the preamble and make it smaller. assert(!CI.getFrontendOpts().SkipFunctionBodies); CI.getFrontendOpts().SkipFunctionBodies = true; + // We don't want to write comment locations into PCH. They are racy and slow + // to read back. We rely on dynamic index for the comments instead. + CI.getPreprocessorOpts().WriteCommentListToPCH = false; CppFilePreambleCallbacks SerializedDeclsCollector(FileName, PreambleCallback); if (Inputs.FS->setCurrentWorkingDirectory(Inputs.CompileCommand.Directory)) { Modified: clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp?rev=336540&r1=336539&r2=336540&view=diff ============================================================================== --- clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp (original) +++ clang-tools-extra/trunk/clangd/CodeCompletionStrings.cpp Mon Jul 9 04:33:31 2018 @@ -32,34 +32,6 @@ void appendEscapeSnippet(const llvm::Str } } -bool canRequestComment(const ASTContext &Ctx, const NamedDecl &D, - bool CommentsFromHeaders) { - if (CommentsFromHeaders) - return true; - auto &SourceMgr = Ctx.getSourceManager(); - // Accessing comments for decls from invalid preamble can lead to crashes. - // So we only return comments from the main file when doing code completion. - // For indexing, we still read all the comments. - // FIXME: find a better fix, e.g. store file contents in the preamble or get - // doc comments from the index. - auto canRequestForDecl = [&](const NamedDecl &D) -> bool { - for (auto *Redecl : D.redecls()) { - auto Loc = SourceMgr.getSpellingLoc(Redecl->getLocation()); - if (!SourceMgr.isWrittenInMainFile(Loc)) - return false; - } - return true; - }; - // First, check the decl itself. - if (!canRequestForDecl(D)) - return false; - // Completion also returns comments for properties, corresponding to ObjC - // methods. - const ObjCMethodDecl *M = dyn_cast<ObjCMethodDecl>(&D); - const ObjCPropertyDecl *PDecl = M ? M->findPropertyDecl() : nullptr; - return !PDecl || canRequestForDecl(*PDecl); -} - bool LooksLikeDocComment(llvm::StringRef CommentText) { // We don't report comments that only contain "special" chars. // This avoids reporting various delimiters, like: @@ -87,12 +59,13 @@ std::string getDocComment(const ASTConte // the comments for namespaces. return ""; } - if (!canRequestComment(Ctx, *Decl, CommentsFromHeaders)) - return ""; - const RawComment *RC = getCompletionComment(Ctx, Decl); if (!RC) return ""; + + // Sanity check that the comment does not come from the PCH. We choose to not + // write them into PCH, because they are racy and slow to load. + assert(!Ctx.getSourceManager().isLoadedSourceLocation(RC->getLocStart())); std::string Doc = RC->getFormattedText(Ctx.getSourceManager(), Ctx.getDiagnostics()); if (!LooksLikeDocComment(Doc)) return ""; @@ -104,11 +77,14 @@ getParameterDocComment(const ASTContext const CodeCompleteConsumer::OverloadCandidate &Result, unsigned ArgIndex, bool CommentsFromHeaders) { auto *Func = Result.getFunction(); - if (!Func || !canRequestComment(Ctx, *Func, CommentsFromHeaders)) + if (!Func) return ""; const RawComment *RC = getParameterComment(Ctx, Result, ArgIndex); if (!RC) return ""; + // Sanity check that the comment does not come from the PCH. We choose to not + // write them into PCH, because they are racy and slow to load. + assert(!Ctx.getSourceManager().isLoadedSourceLocation(RC->getLocStart())); std::string Doc = RC->getFormattedText(Ctx.getSourceManager(), Ctx.getDiagnostics()); if (!LooksLikeDocComment(Doc)) return ""; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
