diff --git a/clang/lib/Tooling/Syntax/Tokens.cpp b/clang/lib/Tooling/Syntax/Tokens.cpp --- a/clang/lib/Tooling/Syntax/Tokens.cpp +++ b/clang/lib/Tooling/Syntax/Tokens.cpp @@ -500,196 +500,150 @@ } TokenBuffer build() && { - buildSpelledTokens(); - - // Walk over expanded tokens and spelled tokens in parallel, building the - // mappings between those using source locations. - // To correctly recover empty macro expansions, we also take locations - // reported to PPCallbacks::MacroExpands into account as we do not have any - // expanded tokens with source locations to guide us. - - // The 'eof' token is special, it is not part of spelled token stream. We - // handle it separately at the end. assert(!Result.ExpandedTokens.empty()); assert(Result.ExpandedTokens.back().kind() == tok::eof); - for (unsigned I = 0; I < Result.ExpandedTokens.size() - 1; ++I) { - // (!) I might be updated by the following call. - processExpandedToken(I); - } - // 'eof' not handled in the loop, do it here. - assert(SM.getMainFileID() == - SM.getFileID(Result.ExpandedTokens.back().location())); - fillGapUntil(Result.Files[SM.getMainFileID()], - Result.ExpandedTokens.back().location(), - Result.ExpandedTokens.size() - 1); - Result.Files[SM.getMainFileID()].EndExpanded = Result.ExpandedTokens.size(); + // Tokenize every file that contributed tokens to the expanded stream. + buildSpelledTokens(); - // Some files might have unaccounted spelled tokens at the end, add an empty - // mapping for those as they did not have expanded counterparts. - fillGapsAtEndOfFiles(); + // The expanded token stream consists of runs of tokens that came from + // the same source (a macro expansion, part of a file etc). + // Between these runs are the logical positions of spelled tokens that + // didn't expand to anything. + while (NextExpanded < Result.ExpandedTokens.size() - 1 /* eof */) { + // Create empty mappings for spelled tokens that expanded to nothing here. + // Advances NextSpelled, but NextExpanded is unchanged. + discard(); + // Create mapping for a contiguous run of expanded tokens. + // Advances NextExpanded past the run, and NextSpelled accordingly. + advance(); + } + // If any tokens remain in any of the files, they didn't expand to anything. + // Create empty mappings up until the end of the file. + for (const auto& File : Result.Files) + discard(File.first); return std::move(Result); } private: - /// Process the next token in an expanded stream and move corresponding - /// spelled tokens, record any mapping if needed. - /// (!) \p I will be updated if this had to skip tokens, e.g. for macros. - void processExpandedToken(unsigned &I) { - auto L = Result.ExpandedTokens[I].location(); - if (L.isMacroID()) { - processMacroExpansion(SM.getExpansionRange(L), I); - return; - } - if (L.isFileID()) { - auto FID = SM.getFileID(L); - TokenBuffer::MarkedFile &File = Result.Files[FID]; - - fillGapUntil(File, L, I); - - // Skip the token. - assert(File.SpelledTokens[NextSpelled[FID]].location() == L && - "no corresponding token in the spelled stream"); - ++NextSpelled[FID]; - return; + // Consume a sequence of spelled tokens that didn't expand to anything. + // In the simplest case, skips spelled tokens until finding one that produced + // the NextExpanded token, and creates an empty mapping for them. + // If Drain is provided, skips remaining tokens from that file instead. + void discard(llvm::Optional Drain = llvm::None) { + SourceLocation Target = + Drain ? SM.getLocForEndOfFile(*Drain) + : SM.getExpansionLoc( + Result.ExpandedTokens[NextExpanded].location()); + FileID File = SM.getFileID(Target); + const auto &SpelledTokens = Result.Files[File].SpelledTokens; + auto &NextSpelled = this->NextSpelled[File]; + + TokenBuffer::Mapping Mapping; + Mapping.BeginSpelled = NextSpelled; + // When dropping trailing tokens from a file, the empty mapping should + // be positioned within the file's expanded-token range (at the end). + Mapping.BeginExpanded = Mapping.EndExpanded = + Drain ? Result.Files[*Drain].EndExpanded : NextExpanded; + // We may want to split into several adjacent empty mappings. + // FlushMapping() emits the current mapping and starts a new one. + auto FlushMapping = [&, this] { + Mapping.EndSpelled = NextSpelled; + if (Mapping.BeginSpelled != Mapping.EndSpelled) + Result.Files[File].Mappings.push_back(Mapping); + Mapping.BeginSpelled = NextSpelled; + }; + + while (NextSpelled < SpelledTokens.size() && + SpelledTokens[NextSpelled].location() < Target) { + // If we know of mapping bounds at [Next, KnownEnd] (e.g. macro expansion) + // then we want to partition our (empty) mapping. + // [Start, Next) [Next, KnownEnd] (KnownEnd, Target) + SourceLocation KnownEnd = CollectedExpansions.lookup( + SpelledTokens[NextSpelled].location().getRawEncoding()); + if (KnownEnd.isValid()) { + FlushMapping(); // Emits [Start, NextSpelled) + while (NextSpelled < SpelledTokens.size() && + SpelledTokens[NextSpelled].location() <= KnownEnd) + ++NextSpelled; + FlushMapping(); // Emits [NextSpelled, KnownEnd] + // Now the loop contitues and will emit (KnownEnd, Target). + } else { + ++NextSpelled; + } } + FlushMapping(); } - /// Skipped expanded and spelled tokens of a macro expansion that covers \p - /// SpelledRange. Add a corresponding mapping. - /// (!) \p I will be the index of the last token in an expansion after this - /// function returns. - void processMacroExpansion(CharSourceRange SpelledRange, unsigned &I) { - auto FID = SM.getFileID(SpelledRange.getBegin()); - assert(FID == SM.getFileID(SpelledRange.getEnd())); - TokenBuffer::MarkedFile &File = Result.Files[FID]; - - fillGapUntil(File, SpelledRange.getBegin(), I); - - // Skip all expanded tokens from the same macro expansion. - unsigned BeginExpanded = I; - for (; I + 1 < Result.ExpandedTokens.size(); ++I) { - auto NextL = Result.ExpandedTokens[I + 1].location(); - if (!NextL.isMacroID() || - SM.getExpansionLoc(NextL) != SpelledRange.getBegin()) - break; + // Consumes the NextExpanded token and others that are part of the same run. + // Increases NextExpanded and NextSpelled by at least one, and adds a mapping + // (unless this is a run of file tokens, which we represent with no mapping). + void advance() { + const syntax::Token &Tok = Result.ExpandedTokens[NextExpanded]; + SourceLocation Expansion = SM.getExpansionLoc(Tok.location()); + FileID File = SM.getFileID(Expansion); + const auto &SpelledTokens = Result.Files[File].SpelledTokens; + auto &NextSpelled = this->NextSpelled[File]; + + if (Tok.location().isFileID()) { + // A run of file tokens continues while the expanded/spelled tokens match. + while (NextSpelled < SpelledTokens.size() && + NextExpanded < Result.ExpandedTokens.size() && + SpelledTokens[NextSpelled].location() == + Result.ExpandedTokens[NextExpanded].location()) { + ++NextSpelled; + ++NextExpanded; + } + // We need no mapping for file tokens copied to the expanded stream. + } else { + // We found a new macro expansion. We should have its spelling bounds. + auto End = CollectedExpansions.lookup(Expansion.getRawEncoding()); + assert(End.isValid() && "Macro expansion wasn't captured?"); + + // Mapping starts here... + TokenBuffer::Mapping Mapping; + Mapping.BeginExpanded = NextExpanded; + Mapping.BeginSpelled = NextSpelled; + // ... consumes spelled tokens within bounds we captured ... + while (NextSpelled < SpelledTokens.size() && + SpelledTokens[NextSpelled].location() <= End) + ++NextSpelled; + // ... consumes expanded tokens rooted at the same expansion ... + while (NextExpanded < Result.ExpandedTokens.size() && + SM.getExpansionLoc( + Result.ExpandedTokens[NextExpanded].location()) == Expansion) + ++NextExpanded; + // ... and ends here. + Mapping.EndExpanded = NextExpanded; + Mapping.EndSpelled = NextSpelled; + Result.Files[File].Mappings.push_back(Mapping); } - unsigned EndExpanded = I + 1; - consumeMapping(File, SM.getFileOffset(SpelledRange.getEnd()), BeginExpanded, - EndExpanded, NextSpelled[FID]); } /// Initializes TokenBuffer::Files and fills spelled tokens and expanded /// ranges for each of the files. void buildSpelledTokens() { for (unsigned I = 0; I < Result.ExpandedTokens.size(); ++I) { - auto FID = - SM.getFileID(SM.getExpansionLoc(Result.ExpandedTokens[I].location())); + const auto &Tok = Result.ExpandedTokens[I]; + auto FID = SM.getFileID(SM.getExpansionLoc(Tok.location())); auto It = Result.Files.try_emplace(FID); TokenBuffer::MarkedFile &File = It.first->second; - File.EndExpanded = I + 1; + // The eof token should not be considered part of the main-file's range. + File.EndExpanded = Tok.kind() == tok::eof ? I : I + 1; + if (!It.second) continue; // we have seen this file before. - // This is the first time we see this file. File.BeginExpanded = I; File.SpelledTokens = tokenize(FID, SM, LangOpts); } } - void consumeEmptyMapping(TokenBuffer::MarkedFile &File, unsigned EndOffset, - unsigned ExpandedIndex, unsigned &SpelledIndex) { - consumeMapping(File, EndOffset, ExpandedIndex, ExpandedIndex, SpelledIndex); - } - - /// Consumes spelled tokens that form a macro expansion and adds a entry to - /// the resulting token buffer. - /// (!) SpelledIndex is updated in-place. - void consumeMapping(TokenBuffer::MarkedFile &File, unsigned EndOffset, - unsigned BeginExpanded, unsigned EndExpanded, - unsigned &SpelledIndex) { - // We need to record this mapping before continuing. - unsigned MappingBegin = SpelledIndex; - ++SpelledIndex; - - bool HitMapping = - tryConsumeSpelledUntil(File, EndOffset + 1, SpelledIndex).hasValue(); - (void)HitMapping; - assert(!HitMapping && "recursive macro expansion?"); - - TokenBuffer::Mapping M; - M.BeginExpanded = BeginExpanded; - M.EndExpanded = EndExpanded; - M.BeginSpelled = MappingBegin; - M.EndSpelled = SpelledIndex; - - File.Mappings.push_back(M); - } - - /// Consumes spelled tokens until location \p L is reached and adds a mapping - /// covering the consumed tokens. The mapping will point to an empty expanded - /// range at position \p ExpandedIndex. - void fillGapUntil(TokenBuffer::MarkedFile &File, SourceLocation L, - unsigned ExpandedIndex) { - assert(L.isFileID()); - FileID FID; - unsigned Offset; - std::tie(FID, Offset) = SM.getDecomposedLoc(L); - - unsigned &SpelledIndex = NextSpelled[FID]; - unsigned MappingBegin = SpelledIndex; - while (true) { - auto EndLoc = tryConsumeSpelledUntil(File, Offset, SpelledIndex); - if (SpelledIndex != MappingBegin) { - TokenBuffer::Mapping M; - M.BeginSpelled = MappingBegin; - M.EndSpelled = SpelledIndex; - M.BeginExpanded = M.EndExpanded = ExpandedIndex; - File.Mappings.push_back(M); - } - if (!EndLoc) - break; - consumeEmptyMapping(File, SM.getFileOffset(*EndLoc), ExpandedIndex, - SpelledIndex); - - MappingBegin = SpelledIndex; - } - }; - - /// Consumes spelled tokens until it reaches Offset or a mapping boundary, - /// i.e. a name of a macro expansion or the start '#' token of a PP directive. - /// (!) NextSpelled is updated in place. - /// - /// returns None if \p Offset was reached, otherwise returns the end location - /// of a mapping that starts at \p NextSpelled. - llvm::Optional - tryConsumeSpelledUntil(TokenBuffer::MarkedFile &File, unsigned Offset, - unsigned &NextSpelled) { - for (; NextSpelled < File.SpelledTokens.size(); ++NextSpelled) { - auto L = File.SpelledTokens[NextSpelled].location(); - if (Offset <= SM.getFileOffset(L)) - return llvm::None; // reached the offset we are looking for. - auto Mapping = CollectedExpansions.find(L.getRawEncoding()); - if (Mapping != CollectedExpansions.end()) - return Mapping->second; // found a mapping before the offset. - } - return llvm::None; // no more tokens, we "reached" the offset. - } - - /// Adds empty mappings for unconsumed spelled tokens at the end of each file. - void fillGapsAtEndOfFiles() { - for (auto &F : Result.Files) { - if (F.second.SpelledTokens.empty()) - continue; - fillGapUntil(F.second, F.second.SpelledTokens.back().endLocation(), - F.second.EndExpanded); - } - } - TokenBuffer Result; - /// For each file, a position of the next spelled token we will consume. + // Cursor within the expanded token stream, and each file. + unsigned NextExpanded = 0; llvm::DenseMap NextSpelled; PPExpansions CollectedExpansions; const SourceManager &SM;