//===--- TokenLexer.cpp - Lex from a token stream -------------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements the TokenLexer interface. // //===----------------------------------------------------------------------===// #include "clang/Lex/TokenLexer.h" #include "MacroArgs.h" #include "clang/Lex/MacroInfo.h" #include "clang/Lex/Preprocessor.h" #include "clang/Basic/SourceManager.h" #include "clang/Lex/LexDiagnostic.h" #include "llvm/ADT/SmallString.h" using namespace clang; /// Create a TokenLexer for the specified macro with the specified actual /// arguments. Note that this ctor takes ownership of the ActualArgs pointer. void TokenLexer::Init(Token &Tok, SourceLocation ELEnd, MacroInfo *MI, MacroArgs *Actuals) { // If the client is reusing a TokenLexer, make sure to free any memory // associated with it. destroy(); Macro = MI; ActualArgs = Actuals; CurToken = 0; ExpandLocStart = Tok.getLocation(); ExpandLocEnd = ELEnd; AtStartOfLine = Tok.isAtStartOfLine(); HasLeadingSpace = Tok.hasLeadingSpace(); Tokens = &*Macro->tokens_begin(); OwnsTokens = false; DisableMacroExpansion = false; NumTokens = Macro->tokens_end()-Macro->tokens_begin(); MacroExpansionStart = SourceLocation(); SourceManager &SM = PP.getSourceManager(); MacroStartSLocOffset = SM.getNextLocalOffset(); if (NumTokens > 0) { assert(Tokens[0].getLocation().isValid()); assert((Tokens[0].getLocation().isFileID() || Tokens[0].is(tok::comment)) && "Macro defined in macro?"); assert(ExpandLocStart.isValid()); // Reserve a source location entry chunk for the length of the macro // definition. Tokens that get lexed directly from the definition will // have their locations pointing inside this chunk. This is to avoid // creating separate source location entries for each token. MacroDefStart = SM.getExpansionLoc(Tokens[0].getLocation()); MacroDefLength = Macro->getDefinitionLength(SM); MacroExpansionStart = SM.createExpansionLoc(MacroDefStart, ExpandLocStart, ExpandLocEnd, MacroDefLength); } // If this is a function-like macro, expand the arguments and change // Tokens to point to the expanded tokens. if (Macro->isFunctionLike() && Macro->getNumArgs()) ExpandFunctionArguments(); // Mark the macro as currently disabled, so that it is not recursively // expanded. The macro must be disabled only after argument pre-expansion of // function-like macro arguments occurs. Macro->DisableMacro(); } /// Create a TokenLexer for the specified token stream. This does not /// take ownership of the specified token vector. void TokenLexer::Init(const Token *TokArray, unsigned NumToks, bool disableMacroExpansion, bool ownsTokens) { // If the client is reusing a TokenLexer, make sure to free any memory // associated with it. destroy(); Macro = 0; ActualArgs = 0; Tokens = TokArray; OwnsTokens = ownsTokens; DisableMacroExpansion = disableMacroExpansion; NumTokens = NumToks; CurToken = 0; ExpandLocStart = ExpandLocEnd = SourceLocation(); AtStartOfLine = false; HasLeadingSpace = false; MacroExpansionStart = SourceLocation(); // Set HasLeadingSpace/AtStartOfLine so that the first token will be // returned unmodified. if (NumToks != 0) { AtStartOfLine = TokArray[0].isAtStartOfLine(); HasLeadingSpace = TokArray[0].hasLeadingSpace(); } } void TokenLexer::destroy() { // If this was a function-like macro that actually uses its arguments, delete // the expanded tokens. if (OwnsTokens) { delete [] Tokens; Tokens = 0; OwnsTokens = false; } // TokenLexer owns its formal arguments. if (ActualArgs) ActualArgs->destroy(PP); } /// Expand the arguments of a function-like macro so that we can quickly /// return preexpanded tokens from Tokens. void TokenLexer::ExpandFunctionArguments() { SmallVector<Token, 128> ResultToks; // Loop through 'Tokens', expanding them into ResultToks. Keep // track of whether we change anything. If not, no need to keep them. If so, // we install the newly expanded sequence as the new 'Tokens' list. bool MadeChange = false; // NextTokGetsSpace - When this is true, the next token appended to the // output list will get a leading space, regardless of whether it had one to // begin with or not. This is used for placemarker support. bool NextTokGetsSpace = false; for (unsigned i = 0, e = NumTokens; i != e; ++i) { // If we found the stringify operator, get the argument stringified. The // preprocessor already verified that the following token is a macro name // when the #define was parsed. const Token &CurTok = Tokens[i]; if (CurTok.is(tok::hash) || CurTok.is(tok::hashat)) { int ArgNo = Macro->getArgumentNum(Tokens[i+1].getIdentifierInfo()); assert(ArgNo != -1 && "Token following # is not an argument?"); SourceLocation ExpansionLocStart = getExpansionLocForMacroDefLoc(CurTok.getLocation()); SourceLocation ExpansionLocEnd = getExpansionLocForMacroDefLoc(Tokens[i+1].getLocation()); Token Res; if (CurTok.is(tok::hash)) // Stringify Res = ActualArgs->getStringifiedArgument(ArgNo, PP, ExpansionLocStart, ExpansionLocEnd); else { // 'charify': don't bother caching these. Res = MacroArgs::StringifyArgument(ActualArgs->getUnexpArgument(ArgNo), PP, true, ExpansionLocStart, ExpansionLocEnd); } // The stringified/charified string leading space flag gets set to match // the #/#@ operator. if (CurTok.hasLeadingSpace() || NextTokGetsSpace) Res.setFlag(Token::LeadingSpace); ResultToks.push_back(Res); MadeChange = true; ++i; // Skip arg name. NextTokGetsSpace = false; continue; } // Otherwise, if this is not an argument token, just add the token to the // output buffer. IdentifierInfo *II = CurTok.getIdentifierInfo(); int ArgNo = II ? Macro->getArgumentNum(II) : -1; if (ArgNo == -1) { // This isn't an argument, just add it. ResultToks.push_back(CurTok); if (NextTokGetsSpace) { ResultToks.back().setFlag(Token::LeadingSpace); NextTokGetsSpace = false; } continue; } // An argument is expanded somehow, the result is different than the // input. MadeChange = true; // Otherwise, this is a use of the argument. Find out if there is a paste // (##) operator before or after the argument. bool PasteBefore = !ResultToks.empty() && ResultToks.back().is(tok::hashhash); bool PasteAfter = i+1 != e && Tokens[i+1].is(tok::hashhash); // If it is not the LHS/RHS of a ## operator, we must pre-expand the // argument and substitute the expanded tokens into the result. This is // C99 6.10.3.1p1. if (!PasteBefore && !PasteAfter) { const Token *ResultArgToks; // Only preexpand the argument if it could possibly need it. This // avoids some work in common cases. const Token *ArgTok = ActualArgs->getUnexpArgument(ArgNo); if (ActualArgs->ArgNeedsPreexpansion(ArgTok, PP)) ResultArgToks = &ActualArgs->getPreExpArgument(ArgNo, Macro, PP)[0]; else ResultArgToks = ArgTok; // Use non-preexpanded tokens. // If the arg token expanded into anything, append it. if (ResultArgToks->isNot(tok::eof)) { unsigned FirstResult = ResultToks.size(); unsigned NumToks = MacroArgs::getArgLength(ResultArgToks); ResultToks.append(ResultArgToks, ResultArgToks+NumToks); // If the '##' came from expanding an argument, turn it into 'unknown' // to avoid pasting. for (unsigned i = FirstResult, e = ResultToks.size(); i != e; ++i) { Token &Tok = ResultToks[i]; if (Tok.is(tok::hashhash)) Tok.setKind(tok::unknown); } if(ExpandLocStart.isValid()) { updateLocForMacroArgTokens(CurTok.getLocation(), ResultToks.begin()+FirstResult, ResultToks.end()); } // If any tokens were substituted from the argument, the whitespace // before the first token should match the whitespace of the arg // identifier. ResultToks[FirstResult].setFlagValue(Token::LeadingSpace, CurTok.hasLeadingSpace() || NextTokGetsSpace); NextTokGetsSpace = false; } else { // If this is an empty argument, and if there was whitespace before the // formal token, make sure the next token gets whitespace before it. NextTokGetsSpace = CurTok.hasLeadingSpace(); } continue; } // Okay, we have a token that is either the LHS or RHS of a paste (##) // argument. It gets substituted as its non-pre-expanded tokens. const Token *ArgToks = ActualArgs->getUnexpArgument(ArgNo); unsigned NumToks = MacroArgs::getArgLength(ArgToks); if (NumToks) { // Not an empty argument? // If this is the GNU ", ## __VA_ARGS__" extension, and we just learned // that __VA_ARGS__ expands to multiple tokens, avoid a pasting error when // the expander trys to paste ',' with the first token of the __VA_ARGS__ // expansion. if (PasteBefore && ResultToks.size() >= 2 && ResultToks[ResultToks.size()-2].is(tok::comma) && (unsigned)ArgNo == Macro->getNumArgs()-1 && Macro->isVariadic()) { // Remove the paste operator, report use of the extension. PP.Diag(ResultToks.back().getLocation(), diag::ext_paste_comma); ResultToks.pop_back(); } ResultToks.append(ArgToks, ArgToks+NumToks); // If the '##' came from expanding an argument, turn it into 'unknown' // to avoid pasting. for (unsigned i = ResultToks.size() - NumToks, e = ResultToks.size(); i != e; ++i) { Token &Tok = ResultToks[i]; if (Tok.is(tok::hashhash)) Tok.setKind(tok::unknown); } if (ExpandLocStart.isValid()) { updateLocForMacroArgTokens(CurTok.getLocation(), ResultToks.end()-NumToks, ResultToks.end()); } // If this token (the macro argument) was supposed to get leading // whitespace, transfer this information onto the first token of the // expansion. // // Do not do this if the paste operator occurs before the macro argument, // as in "A ## MACROARG". In valid code, the first token will get // smooshed onto the preceding one anyway (forming AMACROARG). In // assembler-with-cpp mode, invalid pastes are allowed through: in this // case, we do not want the extra whitespace to be added. For example, // we want ". ## foo" -> ".foo" not ". foo". if ((CurTok.hasLeadingSpace() || NextTokGetsSpace) && !PasteBefore) ResultToks[ResultToks.size()-NumToks].setFlag(Token::LeadingSpace); NextTokGetsSpace = false; continue; } // If an empty argument is on the LHS or RHS of a paste, the standard (C99 // 6.10.3.3p2,3) calls for a bunch of placemarker stuff to occur. We // implement this by eating ## operators when a LHS or RHS expands to // empty. NextTokGetsSpace |= CurTok.hasLeadingSpace(); if (PasteAfter) { // Discard the argument token and skip (don't copy to the expansion // buffer) the paste operator after it. NextTokGetsSpace |= Tokens[i+1].hasLeadingSpace(); ++i; continue; } // If this is on the RHS of a paste operator, we've already copied the // paste operator to the ResultToks list. Remove it. assert(PasteBefore && ResultToks.back().is(tok::hashhash)); NextTokGetsSpace |= ResultToks.back().hasLeadingSpace(); ResultToks.pop_back(); // If this is the __VA_ARGS__ token, and if the argument wasn't provided, // and if the macro had at least one real argument, and if the token before // the ## was a comma, remove the comma. if ((unsigned)ArgNo == Macro->getNumArgs()-1 && // is __VA_ARGS__ ActualArgs->isVarargsElidedUse() && // Argument elided. !ResultToks.empty() && ResultToks.back().is(tok::comma)) { // Never add a space, even if the comma, ##, or arg had a space. NextTokGetsSpace = false; // Remove the paste operator, report use of the extension. PP.Diag(ResultToks.back().getLocation(), diag::ext_paste_comma); ResultToks.pop_back(); // If the comma was right after another paste (e.g. "X##,##__VA_ARGS__"), // then removal of the comma should produce a placemarker token (in C99 // terms) which we model by popping off the previous ##, giving us a plain // "X" when __VA_ARGS__ is empty. if (!ResultToks.empty() && ResultToks.back().is(tok::hashhash)) ResultToks.pop_back(); } continue; } // If anything changed, install this as the new Tokens list. if (MadeChange) { assert(!OwnsTokens && "This would leak if we already own the token list"); // This is deleted in the dtor. NumTokens = ResultToks.size(); // The tokens will be added to Preprocessor's cache and will be removed // when this TokenLexer finishes lexing them. Tokens = PP.cacheMacroExpandedTokens(this, ResultToks); // The preprocessor cache of macro expanded tokens owns these tokens,not us. OwnsTokens = false; } } /// Lex - Lex and return a token from this macro stream. /// void TokenLexer::Lex(Token &Tok) { // Lexing off the end of the macro, pop this macro off the expansion stack. if (isAtEnd()) { // If this is a macro (not a token stream), mark the macro enabled now // that it is no longer being expanded. if (Macro) Macro->EnableMacro(); // Pop this context off the preprocessors lexer stack and get the next // token. This will delete "this" so remember the PP instance var. Preprocessor &PPCache = PP; if (PP.HandleEndOfTokenLexer(Tok)) return; // HandleEndOfTokenLexer may not return a token. If it doesn't, lex // whatever is next. return PPCache.Lex(Tok); } SourceManager &SM = PP.getSourceManager(); // If this is the first token of the expanded result, we inherit spacing // properties later. bool isFirstToken = CurToken == 0; // Get the next token to return. Tok = Tokens[CurToken++]; bool TokenIsFromPaste = false; // If this token is followed by a token paste (##) operator, paste the tokens! // Note that ## is a normal token when not expanding a macro. if (!isAtEnd() && Tokens[CurToken].is(tok::hashhash) && Macro) { // When handling the microsoft /##/ extension, the final token is // returned by PasteTokens, not the pasted token. if (PasteTokens(Tok)) return; TokenIsFromPaste = true; } // The token's current location indicate where the token was lexed from. We // need this information to compute the spelling of the token, but any // diagnostics for the expanded token should appear as if they came from // ExpansionLoc. Pull this information together into a new SourceLocation // that captures all of this. if (ExpandLocStart.isValid() && // Don't do this for token streams. // Check that the token's location was not already set properly. SM.isBeforeInSLocAddrSpace(Tok.getLocation(), MacroStartSLocOffset)) { SourceLocation instLoc; if (Tok.is(tok::comment)) { instLoc = SM.createExpansionLoc(Tok.getLocation(), ExpandLocStart, ExpandLocEnd, Tok.getLength()); } else { instLoc = getExpansionLocForMacroDefLoc(Tok.getLocation()); } Tok.setLocation(instLoc); } // If this is the first token, set the lexical properties of the token to // match the lexical properties of the macro identifier. if (isFirstToken) { Tok.setFlagValue(Token::StartOfLine , AtStartOfLine); Tok.setFlagValue(Token::LeadingSpace, HasLeadingSpace); } // Handle recursive expansion! if (!Tok.isAnnotation() && Tok.getIdentifierInfo() != 0) { // Change the kind of this identifier to the appropriate token kind, e.g. // turning "for" into a keyword. IdentifierInfo *II = Tok.getIdentifierInfo(); Tok.setKind(II->getTokenID()); // If this identifier was poisoned and from a paste, emit an error. This // won't be handled by Preprocessor::HandleIdentifier because this is coming // from a macro expansion. if (II->isPoisoned() && TokenIsFromPaste) { PP.HandlePoisonedIdentifier(Tok); } if (!DisableMacroExpansion && II->isHandleIdentifierCase()) PP.HandleIdentifier(Tok); } // Otherwise, return a normal token. } /// PasteTokens - Tok is the LHS of a ## operator, and CurToken is the ## /// operator. Read the ## and RHS, and paste the LHS/RHS together. If there /// are more ## after it, chomp them iteratively. Return the result as Tok. /// If this returns true, the caller should immediately return the token. bool TokenLexer::PasteTokens(Token &Tok) { SmallString<128> Buffer; const char *ResultTokStrPtr = 0; SourceLocation StartLoc = Tok.getLocation(); SourceLocation PasteOpLoc; do { // Consume the ## operator. PasteOpLoc = Tokens[CurToken].getLocation(); ++CurToken; assert(!isAtEnd() && "No token on the RHS of a paste operator!"); // Get the RHS token. const Token &RHS = Tokens[CurToken]; // Allocate space for the result token. This is guaranteed to be enough for // the two tokens. Buffer.resize(Tok.getLength() + RHS.getLength()); // Get the spelling of the LHS token in Buffer. const char *BufPtr = &Buffer[0]; bool Invalid = false; unsigned LHSLen = PP.getSpelling(Tok, BufPtr, &Invalid); if (BufPtr != &Buffer[0]) // Really, we want the chars in Buffer! memcpy(&Buffer[0], BufPtr, LHSLen); if (Invalid) return true; BufPtr = &Buffer[LHSLen]; unsigned RHSLen = PP.getSpelling(RHS, BufPtr, &Invalid); if (Invalid) return true; if (BufPtr != &Buffer[LHSLen]) // Really, we want the chars in Buffer! memcpy(&Buffer[LHSLen], BufPtr, RHSLen); // Trim excess space. Buffer.resize(LHSLen+RHSLen); // Plop the pasted result (including the trailing newline and null) into a // scratch buffer where we can lex it. Token ResultTokTmp; ResultTokTmp.startToken(); // Claim that the tmp token is a string_literal so that we can get the // character pointer back from CreateString in getLiteralData(). ResultTokTmp.setKind(tok::string_literal); PP.CreateString(Buffer, ResultTokTmp); SourceLocation ResultTokLoc = ResultTokTmp.getLocation(); ResultTokStrPtr = ResultTokTmp.getLiteralData(); // Lex the resultant pasted token into Result. Token Result; if (Tok.isAnyIdentifier() && RHS.isAnyIdentifier()) { // Common paste case: identifier+identifier = identifier. Avoid creating // a lexer and other overhead. PP.IncrementPasteCounter(true); Result.startToken(); Result.setKind(tok::raw_identifier); Result.setRawIdentifierData(ResultTokStrPtr); Result.setLocation(ResultTokLoc); Result.setLength(LHSLen+RHSLen); } else { PP.IncrementPasteCounter(false); assert(ResultTokLoc.isFileID() && "Should be a raw location into scratch buffer"); SourceManager &SourceMgr = PP.getSourceManager(); FileID LocFileID = SourceMgr.getFileID(ResultTokLoc); bool Invalid = false; const char *ScratchBufStart = SourceMgr.getBufferData(LocFileID, &Invalid).data(); if (Invalid) return false; // Make a lexer to lex this string from. Lex just this one token. // Make a lexer object so that we lex and expand the paste result. Lexer TL(SourceMgr.getLocForStartOfFile(LocFileID), PP.getLangOpts(), ScratchBufStart, ResultTokStrPtr, ResultTokStrPtr+LHSLen+RHSLen); // Lex a token in raw mode. This way it won't look up identifiers // automatically, lexing off the end will return an eof token, and // warnings are disabled. This returns true if the result token is the // entire buffer. bool isInvalid = !TL.LexFromRawLexer(Result); // If we got an EOF token, we didn't form even ONE token. For example, we // did "/ ## /" to get "//". isInvalid |= Result.is(tok::eof); // If pasting the two tokens didn't form a full new token, this is an // error. This occurs with "x ## +" and other stuff. Return with Tok // unmodified and with RHS as the next token to lex. if (isInvalid) { // Test for the Microsoft extension of /##/ turning into // here on the // error path. if (PP.getLangOpts().MicrosoftExt && Tok.is(tok::slash) && RHS.is(tok::slash)) { HandleMicrosoftCommentPaste(Tok); return true; } // Do not emit the error when preprocessing assembler code. if (!PP.getLangOpts().AsmPreprocessor) { // Explicitly convert the token location to have proper expansion // information so that the user knows where it came from. SourceManager &SM = PP.getSourceManager(); SourceLocation Loc = SM.createExpansionLoc(PasteOpLoc, ExpandLocStart, ExpandLocEnd, 2); // If we're in microsoft extensions mode, downgrade this from a hard // error to a warning that defaults to an error. This allows // disabling it. PP.Diag(Loc, PP.getLangOpts().MicrosoftExt ? diag::err_pp_bad_paste_ms : diag::err_pp_bad_paste) << Buffer.str(); } // An error has occurred so exit loop. break; } // Turn ## into 'unknown' to avoid # ## # from looking like a paste // operator. if (Result.is(tok::hashhash)) Result.setKind(tok::unknown); } // Transfer properties of the LHS over the Result. Result.setFlagValue(Token::StartOfLine , Tok.isAtStartOfLine()); Result.setFlagValue(Token::LeadingSpace, Tok.hasLeadingSpace()); // Finally, replace LHS with the result, consume the RHS, and iterate. ++CurToken; Tok = Result; } while (!isAtEnd() && Tokens[CurToken].is(tok::hashhash)); SourceLocation EndLoc = Tokens[CurToken - 1].getLocation(); // The token's current location indicate where the token was lexed from. We // need this information to compute the spelling of the token, but any // diagnostics for the expanded token should appear as if the token was // expanded from the full ## expression. Pull this information together into // a new SourceLocation that captures all of this. SourceManager &SM = PP.getSourceManager(); if (StartLoc.isFileID()) StartLoc = getExpansionLocForMacroDefLoc(StartLoc); if (EndLoc.isFileID()) EndLoc = getExpansionLocForMacroDefLoc(EndLoc); Tok.setLocation(SM.createExpansionLoc(Tok.getLocation(), StartLoc, EndLoc, Tok.getLength())); // Now that we got the result token, it will be subject to expansion. Since // token pasting re-lexes the result token in raw mode, identifier information // isn't looked up. As such, if the result is an identifier, look up id info. if (Tok.is(tok::raw_identifier)) { // Look up the identifier info for the token. We disabled identifier lookup // by saying we're skipping contents, so we need to do this manually. PP.LookUpIdentifierInfo(Tok); } return false; } /// isNextTokenLParen - If the next token lexed will pop this macro off the /// expansion stack, return 2. If the next unexpanded token is a '(', return /// 1, otherwise return 0. unsigned TokenLexer::isNextTokenLParen() const { // Out of tokens? if (isAtEnd()) return 2; return Tokens[CurToken].is(tok::l_paren); } /// isParsingPreprocessorDirective - Return true if we are in the middle of a /// preprocessor directive. bool TokenLexer::isParsingPreprocessorDirective() const { return Tokens[NumTokens-1].is(tok::eod) && !isAtEnd(); } /// HandleMicrosoftCommentPaste - In microsoft compatibility mode, /##/ pastes /// together to form a comment that comments out everything in the current /// macro, other active macros, and anything left on the current physical /// source line of the expanded buffer. Handle this by returning the /// first token on the next line. void TokenLexer::HandleMicrosoftCommentPaste(Token &Tok) { // We 'comment out' the rest of this macro by just ignoring the rest of the // tokens that have not been lexed yet, if any. // Since this must be a macro, mark the macro enabled now that it is no longer // being expanded. assert(Macro && "Token streams can't paste comments"); Macro->EnableMacro(); PP.HandleMicrosoftCommentPaste(Tok); } /// \brief If \arg loc is a file ID and points inside the current macro /// definition, returns the appropriate source location pointing at the /// macro expansion source location entry, otherwise it returns an invalid /// SourceLocation. SourceLocation TokenLexer::getExpansionLocForMacroDefLoc(SourceLocation loc) const { assert(ExpandLocStart.isValid() && MacroExpansionStart.isValid() && "Not appropriate for token streams"); assert(loc.isValid() && loc.isFileID()); SourceManager &SM = PP.getSourceManager(); assert(SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength) && "Expected loc to come from the macro definition"); unsigned relativeOffset = 0; SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength, &relativeOffset); return MacroExpansionStart.getLocWithOffset(relativeOffset); } /// \brief Finds the tokens that are consecutive (from the same FileID) /// creates a single SLocEntry, and assigns SourceLocations to each token that /// point to that SLocEntry. e.g for /// assert(foo == bar); /// There will be a single SLocEntry for the "foo == bar" chunk and locations /// for the 'foo', '==', 'bar' tokens will point inside that chunk. /// /// \arg begin_tokens will be updated to a position past all the found /// consecutive tokens. static void updateConsecutiveMacroArgTokens(SourceManager &SM, SourceLocation InstLoc, Token *&begin_tokens, Token * end_tokens) { assert(begin_tokens < end_tokens); SourceLocation FirstLoc = begin_tokens->getLocation(); SourceLocation CurLoc = FirstLoc; // Compare the source location offset of tokens and group together tokens that // are close, even if their locations point to different FileIDs. e.g. // // |bar | foo | cake | (3 tokens from 3 consecutive FileIDs) // ^ ^ // |bar foo cake| (one SLocEntry chunk for all tokens) // // we can perform this "merge" since the token's spelling location depends // on the relative offset. Token *NextTok = begin_tokens + 1; for (; NextTok < end_tokens; ++NextTok) { int RelOffs; if (!SM.isInSameSLocAddrSpace(CurLoc, NextTok->getLocation(), &RelOffs)) break; // Token from different local/loaded location. // Check that token is not before the previous token or more than 50 // "characters" away. if (RelOffs < 0 || RelOffs > 50) break; CurLoc = NextTok->getLocation(); } // For the consecutive tokens, find the length of the SLocEntry to contain // all of them. Token &LastConsecutiveTok = *(NextTok-1); int LastRelOffs = 0; SM.isInSameSLocAddrSpace(FirstLoc, LastConsecutiveTok.getLocation(), &LastRelOffs); unsigned FullLength = LastRelOffs + LastConsecutiveTok.getLength(); // Create a macro expansion SLocEntry that will "contain" all of the tokens. SourceLocation Expansion = SM.createMacroArgExpansionLoc(FirstLoc, InstLoc,FullLength); // Change the location of the tokens from the spelling location to the new // expanded location. for (; begin_tokens < NextTok; ++begin_tokens) { Token &Tok = *begin_tokens; int RelOffs = 0; SM.isInSameSLocAddrSpace(FirstLoc, Tok.getLocation(), &RelOffs); Tok.setLocation(Expansion.getLocWithOffset(RelOffs)); } } /// \brief Creates SLocEntries and updates the locations of macro argument /// tokens to their new expanded locations. /// /// \param ArgIdDefLoc the location of the macro argument id inside the macro /// definition. /// \param Tokens the macro argument tokens to update. void TokenLexer::updateLocForMacroArgTokens(SourceLocation ArgIdSpellLoc, Token *begin_tokens, Token *end_tokens) { SourceManager &SM = PP.getSourceManager(); SourceLocation InstLoc = getExpansionLocForMacroDefLoc(ArgIdSpellLoc); while (begin_tokens < end_tokens) { // If there's only one token just create a SLocEntry for it. if (end_tokens - begin_tokens == 1) { Token &Tok = *begin_tokens; Tok.setLocation(SM.createMacroArgExpansionLoc(Tok.getLocation(), InstLoc, Tok.getLength())); return; } updateConsecutiveMacroArgTokens(SM, InstLoc, begin_tokens, end_tokens); } }