1 //===--- TokenLexer.cpp - Lex from a token stream -------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the TokenLexer interface.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Lex/TokenLexer.h"
15 #include "clang/Lex/MacroArgs.h"
16 #include "clang/Basic/SourceManager.h"
17 #include "clang/Lex/LexDiagnostic.h"
18 #include "clang/Lex/MacroInfo.h"
19 #include "clang/Lex/Preprocessor.h"
20 #include "llvm/ADT/SmallString.h"
21 using namespace clang;
24 /// Create a TokenLexer for the specified macro with the specified actual
25 /// arguments. Note that this ctor takes ownership of the ActualArgs pointer.
26 void TokenLexer::Init(Token &Tok, SourceLocation ELEnd, MacroInfo *MI,
28 // If the client is reusing a TokenLexer, make sure to free any memory
29 // associated with it.
36 ExpandLocStart = Tok.getLocation();
38 AtStartOfLine = Tok.isAtStartOfLine();
39 HasLeadingSpace = Tok.hasLeadingSpace();
40 Tokens = &*Macro->tokens_begin();
42 DisableMacroExpansion = false;
43 NumTokens = Macro->tokens_end()-Macro->tokens_begin();
44 MacroExpansionStart = SourceLocation();
46 SourceManager &SM = PP.getSourceManager();
47 MacroStartSLocOffset = SM.getNextLocalOffset();
50 assert(Tokens[0].getLocation().isValid());
51 assert((Tokens[0].getLocation().isFileID() || Tokens[0].is(tok::comment)) &&
52 "Macro defined in macro?");
53 assert(ExpandLocStart.isValid());
55 // Reserve a source location entry chunk for the length of the macro
56 // definition. Tokens that get lexed directly from the definition will
57 // have their locations pointing inside this chunk. This is to avoid
58 // creating separate source location entries for each token.
59 MacroDefStart = SM.getExpansionLoc(Tokens[0].getLocation());
60 MacroDefLength = Macro->getDefinitionLength(SM);
61 MacroExpansionStart = SM.createExpansionLoc(MacroDefStart,
67 // If this is a function-like macro, expand the arguments and change
68 // Tokens to point to the expanded tokens.
69 if (Macro->isFunctionLike() && Macro->getNumArgs())
70 ExpandFunctionArguments();
72 // Mark the macro as currently disabled, so that it is not recursively
73 // expanded. The macro must be disabled only after argument pre-expansion of
74 // function-like macro arguments occurs.
75 Macro->DisableMacro();
80 /// Create a TokenLexer for the specified token stream. This does not
81 /// take ownership of the specified token vector.
82 void TokenLexer::Init(const Token *TokArray, unsigned NumToks,
83 bool disableMacroExpansion, bool ownsTokens) {
84 // If the client is reusing a TokenLexer, make sure to free any memory
85 // associated with it.
91 OwnsTokens = ownsTokens;
92 DisableMacroExpansion = disableMacroExpansion;
95 ExpandLocStart = ExpandLocEnd = SourceLocation();
96 AtStartOfLine = false;
97 HasLeadingSpace = false;
98 MacroExpansionStart = SourceLocation();
100 // Set HasLeadingSpace/AtStartOfLine so that the first token will be
101 // returned unmodified.
103 AtStartOfLine = TokArray[0].isAtStartOfLine();
104 HasLeadingSpace = TokArray[0].hasLeadingSpace();
109 void TokenLexer::destroy() {
110 // If this was a function-like macro that actually uses its arguments, delete
111 // the expanded tokens.
118 // TokenLexer owns its formal arguments.
119 if (ActualArgs) ActualArgs->destroy(PP);
122 /// Remove comma ahead of __VA_ARGS__, if present, according to compiler dialect
123 /// settings. Returns true if the comma is removed.
124 static bool MaybeRemoveCommaBeforeVaArgs(SmallVectorImpl<Token> &ResultToks,
125 bool &NextTokGetsSpace,
126 bool HasPasteOperator,
127 MacroInfo *Macro, unsigned MacroArgNo,
129 // Is the macro argument __VA_ARGS__?
130 if (!Macro->isVariadic() || MacroArgNo != Macro->getNumArgs()-1)
133 // In Microsoft-compatibility mode, a comma is removed in the expansion
134 // of " ... , __VA_ARGS__ " if __VA_ARGS__ is empty. This extension is
135 // not supported by gcc.
136 if (!HasPasteOperator && !PP.getLangOpts().MicrosoftMode)
139 // GCC removes the comma in the expansion of " ... , ## __VA_ARGS__ " if
140 // __VA_ARGS__ is empty, but not in strict C99 mode where there are no
141 // named arguments, where it remains. In all other modes, including C99
142 // with GNU extensions, it is removed regardless of named arguments.
143 // Microsoft also appears to support this extension, unofficially.
144 if (PP.getLangOpts().C99 && !PP.getLangOpts().GNUMode
145 && Macro->getNumArgs() < 2)
148 // Is a comma available to be removed?
149 if (ResultToks.empty() || !ResultToks.back().is(tok::comma))
152 // Issue an extension diagnostic for the paste operator.
153 if (HasPasteOperator)
154 PP.Diag(ResultToks.back().getLocation(), diag::ext_paste_comma);
157 ResultToks.pop_back();
159 // If the comma was right after another paste (e.g. "X##,##__VA_ARGS__"),
160 // then removal of the comma should produce a placemarker token (in C99
161 // terms) which we model by popping off the previous ##, giving us a plain
162 // "X" when __VA_ARGS__ is empty.
163 if (!ResultToks.empty() && ResultToks.back().is(tok::hashhash))
164 ResultToks.pop_back();
166 // Never add a space, even if the comma, ##, or arg had a space.
167 NextTokGetsSpace = false;
171 /// Expand the arguments of a function-like macro so that we can quickly
172 /// return preexpanded tokens from Tokens.
173 void TokenLexer::ExpandFunctionArguments() {
175 SmallVector<Token, 128> ResultToks;
177 // Loop through 'Tokens', expanding them into ResultToks. Keep
178 // track of whether we change anything. If not, no need to keep them. If so,
179 // we install the newly expanded sequence as the new 'Tokens' list.
180 bool MadeChange = false;
182 // NextTokGetsSpace - When this is true, the next token appended to the
183 // output list will get a leading space, regardless of whether it had one to
184 // begin with or not. This is used for placemarker support.
185 bool NextTokGetsSpace = false;
187 for (unsigned i = 0, e = NumTokens; i != e; ++i) {
188 // If we found the stringify operator, get the argument stringified. The
189 // preprocessor already verified that the following token is a macro name
190 // when the #define was parsed.
191 const Token &CurTok = Tokens[i];
192 if (CurTok.is(tok::hash) || CurTok.is(tok::hashat)) {
193 int ArgNo = Macro->getArgumentNum(Tokens[i+1].getIdentifierInfo());
194 assert(ArgNo != -1 && "Token following # is not an argument?");
196 SourceLocation ExpansionLocStart =
197 getExpansionLocForMacroDefLoc(CurTok.getLocation());
198 SourceLocation ExpansionLocEnd =
199 getExpansionLocForMacroDefLoc(Tokens[i+1].getLocation());
202 if (CurTok.is(tok::hash)) // Stringify
203 Res = ActualArgs->getStringifiedArgument(ArgNo, PP,
207 // 'charify': don't bother caching these.
208 Res = MacroArgs::StringifyArgument(ActualArgs->getUnexpArgument(ArgNo),
214 // The stringified/charified string leading space flag gets set to match
215 // the #/#@ operator.
216 if (CurTok.hasLeadingSpace() || NextTokGetsSpace)
217 Res.setFlag(Token::LeadingSpace);
219 ResultToks.push_back(Res);
221 ++i; // Skip arg name.
222 NextTokGetsSpace = false;
226 // Otherwise, if this is not an argument token, just add the token to the
228 IdentifierInfo *II = CurTok.getIdentifierInfo();
229 int ArgNo = II ? Macro->getArgumentNum(II) : -1;
231 // This isn't an argument, just add it.
232 ResultToks.push_back(CurTok);
234 if (NextTokGetsSpace) {
235 ResultToks.back().setFlag(Token::LeadingSpace);
236 NextTokGetsSpace = false;
241 // An argument is expanded somehow, the result is different than the
245 // Otherwise, this is a use of the argument. Find out if there is a paste
246 // (##) operator before or after the argument.
247 bool NonEmptyPasteBefore =
248 !ResultToks.empty() && ResultToks.back().is(tok::hashhash);
249 bool PasteBefore = i != 0 && Tokens[i-1].is(tok::hashhash);
250 bool PasteAfter = i+1 != e && Tokens[i+1].is(tok::hashhash);
251 assert(!NonEmptyPasteBefore || PasteBefore);
253 // In Microsoft mode, remove the comma before __VA_ARGS__ to ensure there
254 // are no trailing commas if __VA_ARGS__ is empty.
255 if (!PasteBefore && ActualArgs->isVarargsElidedUse() &&
256 MaybeRemoveCommaBeforeVaArgs(ResultToks, NextTokGetsSpace,
257 /*HasPasteOperator=*/false,
261 // If it is not the LHS/RHS of a ## operator, we must pre-expand the
262 // argument and substitute the expanded tokens into the result. This is
264 if (!PasteBefore && !PasteAfter) {
265 const Token *ResultArgToks;
267 // Only preexpand the argument if it could possibly need it. This
268 // avoids some work in common cases.
269 const Token *ArgTok = ActualArgs->getUnexpArgument(ArgNo);
270 if (ActualArgs->ArgNeedsPreexpansion(ArgTok, PP))
271 ResultArgToks = &ActualArgs->getPreExpArgument(ArgNo, Macro, PP)[0];
273 ResultArgToks = ArgTok; // Use non-preexpanded tokens.
275 // If the arg token expanded into anything, append it.
276 if (ResultArgToks->isNot(tok::eof)) {
277 unsigned FirstResult = ResultToks.size();
278 unsigned NumToks = MacroArgs::getArgLength(ResultArgToks);
279 ResultToks.append(ResultArgToks, ResultArgToks+NumToks);
281 // In Microsoft-compatibility mode, we follow MSVC's preprocessing
282 // behavior by not considering single commas from nested macro
283 // expansions as argument separators. Set a flag on the token so we can
284 // test for this later when the macro expansion is processed.
285 if (PP.getLangOpts().MicrosoftMode && NumToks == 1 &&
286 ResultToks.back().is(tok::comma))
287 ResultToks.back().setFlag(Token::IgnoredComma);
289 // If the '##' came from expanding an argument, turn it into 'unknown'
291 for (unsigned i = FirstResult, e = ResultToks.size(); i != e; ++i) {
292 Token &Tok = ResultToks[i];
293 if (Tok.is(tok::hashhash))
294 Tok.setKind(tok::unknown);
297 if(ExpandLocStart.isValid()) {
298 updateLocForMacroArgTokens(CurTok.getLocation(),
299 ResultToks.begin()+FirstResult,
303 // If any tokens were substituted from the argument, the whitespace
304 // before the first token should match the whitespace of the arg
306 ResultToks[FirstResult].setFlagValue(Token::LeadingSpace,
307 CurTok.hasLeadingSpace() ||
309 NextTokGetsSpace = false;
311 // If this is an empty argument, and if there was whitespace before the
312 // formal token, make sure the next token gets whitespace before it.
313 NextTokGetsSpace = CurTok.hasLeadingSpace();
318 // Okay, we have a token that is either the LHS or RHS of a paste (##)
319 // argument. It gets substituted as its non-pre-expanded tokens.
320 const Token *ArgToks = ActualArgs->getUnexpArgument(ArgNo);
321 unsigned NumToks = MacroArgs::getArgLength(ArgToks);
322 if (NumToks) { // Not an empty argument?
323 // If this is the GNU ", ## __VA_ARGS__" extension, and we just learned
324 // that __VA_ARGS__ expands to multiple tokens, avoid a pasting error when
325 // the expander trys to paste ',' with the first token of the __VA_ARGS__
327 if (NonEmptyPasteBefore && ResultToks.size() >= 2 &&
328 ResultToks[ResultToks.size()-2].is(tok::comma) &&
329 (unsigned)ArgNo == Macro->getNumArgs()-1 &&
330 Macro->isVariadic()) {
331 // Remove the paste operator, report use of the extension.
332 PP.Diag(ResultToks.pop_back_val().getLocation(), diag::ext_paste_comma);
335 ResultToks.append(ArgToks, ArgToks+NumToks);
337 // If the '##' came from expanding an argument, turn it into 'unknown'
339 for (unsigned i = ResultToks.size() - NumToks, e = ResultToks.size();
341 Token &Tok = ResultToks[i];
342 if (Tok.is(tok::hashhash))
343 Tok.setKind(tok::unknown);
346 if (ExpandLocStart.isValid()) {
347 updateLocForMacroArgTokens(CurTok.getLocation(),
348 ResultToks.end()-NumToks, ResultToks.end());
351 // If this token (the macro argument) was supposed to get leading
352 // whitespace, transfer this information onto the first token of the
355 // Do not do this if the paste operator occurs before the macro argument,
356 // as in "A ## MACROARG". In valid code, the first token will get
357 // smooshed onto the preceding one anyway (forming AMACROARG). In
358 // assembler-with-cpp mode, invalid pastes are allowed through: in this
359 // case, we do not want the extra whitespace to be added. For example,
360 // we want ". ## foo" -> ".foo" not ". foo".
361 if ((CurTok.hasLeadingSpace() || NextTokGetsSpace) &&
362 !NonEmptyPasteBefore)
363 ResultToks[ResultToks.size()-NumToks].setFlag(Token::LeadingSpace);
365 NextTokGetsSpace = false;
369 // If an empty argument is on the LHS or RHS of a paste, the standard (C99
370 // 6.10.3.3p2,3) calls for a bunch of placemarker stuff to occur. We
371 // implement this by eating ## operators when a LHS or RHS expands to
373 NextTokGetsSpace |= CurTok.hasLeadingSpace();
375 // Discard the argument token and skip (don't copy to the expansion
376 // buffer) the paste operator after it.
377 NextTokGetsSpace |= Tokens[i+1].hasLeadingSpace();
382 // If this is on the RHS of a paste operator, we've already copied the
383 // paste operator to the ResultToks list, unless the LHS was empty too.
386 if (NonEmptyPasteBefore) {
387 assert(ResultToks.back().is(tok::hashhash));
388 NextTokGetsSpace |= ResultToks.pop_back_val().hasLeadingSpace();
391 // If this is the __VA_ARGS__ token, and if the argument wasn't provided,
392 // and if the macro had at least one real argument, and if the token before
393 // the ## was a comma, remove the comma. This is a GCC extension which is
394 // disabled when using -std=c99.
395 if (ActualArgs->isVarargsElidedUse())
396 MaybeRemoveCommaBeforeVaArgs(ResultToks, NextTokGetsSpace,
397 /*HasPasteOperator=*/true,
403 // If anything changed, install this as the new Tokens list.
405 assert(!OwnsTokens && "This would leak if we already own the token list");
406 // This is deleted in the dtor.
407 NumTokens = ResultToks.size();
408 // The tokens will be added to Preprocessor's cache and will be removed
409 // when this TokenLexer finishes lexing them.
410 Tokens = PP.cacheMacroExpandedTokens(this, ResultToks);
412 // The preprocessor cache of macro expanded tokens owns these tokens,not us.
417 /// Lex - Lex and return a token from this macro stream.
419 bool TokenLexer::Lex(Token &Tok) {
420 // Lexing off the end of the macro, pop this macro off the expansion stack.
422 // If this is a macro (not a token stream), mark the macro enabled now
423 // that it is no longer being expanded.
424 if (Macro) Macro->EnableMacro();
427 Tok.setFlagValue(Token::StartOfLine , AtStartOfLine);
428 Tok.setFlagValue(Token::LeadingSpace, HasLeadingSpace);
430 Tok.setFlag(Token::LeadingEmptyMacro);
431 return PP.HandleEndOfTokenLexer(Tok);
434 SourceManager &SM = PP.getSourceManager();
436 // If this is the first token of the expanded result, we inherit spacing
438 bool isFirstToken = CurToken == 0;
440 // Get the next token to return.
441 Tok = Tokens[CurToken++];
443 bool TokenIsFromPaste = false;
445 // If this token is followed by a token paste (##) operator, paste the tokens!
446 // Note that ## is a normal token when not expanding a macro.
447 if (!isAtEnd() && Tokens[CurToken].is(tok::hashhash) && Macro) {
448 // When handling the microsoft /##/ extension, the final token is
449 // returned by PasteTokens, not the pasted token.
450 if (PasteTokens(Tok))
453 TokenIsFromPaste = true;
456 // The token's current location indicate where the token was lexed from. We
457 // need this information to compute the spelling of the token, but any
458 // diagnostics for the expanded token should appear as if they came from
459 // ExpansionLoc. Pull this information together into a new SourceLocation
460 // that captures all of this.
461 if (ExpandLocStart.isValid() && // Don't do this for token streams.
462 // Check that the token's location was not already set properly.
463 SM.isBeforeInSLocAddrSpace(Tok.getLocation(), MacroStartSLocOffset)) {
464 SourceLocation instLoc;
465 if (Tok.is(tok::comment)) {
466 instLoc = SM.createExpansionLoc(Tok.getLocation(),
471 instLoc = getExpansionLocForMacroDefLoc(Tok.getLocation());
474 Tok.setLocation(instLoc);
477 // If this is the first token, set the lexical properties of the token to
478 // match the lexical properties of the macro identifier.
480 Tok.setFlagValue(Token::StartOfLine , AtStartOfLine);
481 Tok.setFlagValue(Token::LeadingSpace, HasLeadingSpace);
482 AtStartOfLine = false;
483 HasLeadingSpace = false;
486 // Handle recursive expansion!
487 if (!Tok.isAnnotation() && Tok.getIdentifierInfo() != 0) {
488 // Change the kind of this identifier to the appropriate token kind, e.g.
489 // turning "for" into a keyword.
490 IdentifierInfo *II = Tok.getIdentifierInfo();
491 Tok.setKind(II->getTokenID());
493 // If this identifier was poisoned and from a paste, emit an error. This
494 // won't be handled by Preprocessor::HandleIdentifier because this is coming
495 // from a macro expansion.
496 if (II->isPoisoned() && TokenIsFromPaste) {
497 PP.HandlePoisonedIdentifier(Tok);
500 if (!DisableMacroExpansion && II->isHandleIdentifierCase())
501 return PP.HandleIdentifier(Tok);
504 // Otherwise, return a normal token.
508 /// PasteTokens - Tok is the LHS of a ## operator, and CurToken is the ##
509 /// operator. Read the ## and RHS, and paste the LHS/RHS together. If there
510 /// are more ## after it, chomp them iteratively. Return the result as Tok.
511 /// If this returns true, the caller should immediately return the token.
512 bool TokenLexer::PasteTokens(Token &Tok) {
513 SmallString<128> Buffer;
514 const char *ResultTokStrPtr = 0;
515 SourceLocation StartLoc = Tok.getLocation();
516 SourceLocation PasteOpLoc;
518 // Consume the ## operator.
519 PasteOpLoc = Tokens[CurToken].getLocation();
521 assert(!isAtEnd() && "No token on the RHS of a paste operator!");
523 // Get the RHS token.
524 const Token &RHS = Tokens[CurToken];
526 // Allocate space for the result token. This is guaranteed to be enough for
528 Buffer.resize(Tok.getLength() + RHS.getLength());
530 // Get the spelling of the LHS token in Buffer.
531 const char *BufPtr = &Buffer[0];
532 bool Invalid = false;
533 unsigned LHSLen = PP.getSpelling(Tok, BufPtr, &Invalid);
534 if (BufPtr != &Buffer[0]) // Really, we want the chars in Buffer!
535 memcpy(&Buffer[0], BufPtr, LHSLen);
539 BufPtr = &Buffer[LHSLen];
540 unsigned RHSLen = PP.getSpelling(RHS, BufPtr, &Invalid);
543 if (BufPtr != &Buffer[LHSLen]) // Really, we want the chars in Buffer!
544 memcpy(&Buffer[LHSLen], BufPtr, RHSLen);
546 // Trim excess space.
547 Buffer.resize(LHSLen+RHSLen);
549 // Plop the pasted result (including the trailing newline and null) into a
550 // scratch buffer where we can lex it.
552 ResultTokTmp.startToken();
554 // Claim that the tmp token is a string_literal so that we can get the
555 // character pointer back from CreateString in getLiteralData().
556 ResultTokTmp.setKind(tok::string_literal);
557 PP.CreateString(Buffer, ResultTokTmp);
558 SourceLocation ResultTokLoc = ResultTokTmp.getLocation();
559 ResultTokStrPtr = ResultTokTmp.getLiteralData();
561 // Lex the resultant pasted token into Result.
564 if (Tok.isAnyIdentifier() && RHS.isAnyIdentifier()) {
565 // Common paste case: identifier+identifier = identifier. Avoid creating
566 // a lexer and other overhead.
567 PP.IncrementPasteCounter(true);
569 Result.setKind(tok::raw_identifier);
570 Result.setRawIdentifierData(ResultTokStrPtr);
571 Result.setLocation(ResultTokLoc);
572 Result.setLength(LHSLen+RHSLen);
574 PP.IncrementPasteCounter(false);
576 assert(ResultTokLoc.isFileID() &&
577 "Should be a raw location into scratch buffer");
578 SourceManager &SourceMgr = PP.getSourceManager();
579 FileID LocFileID = SourceMgr.getFileID(ResultTokLoc);
581 bool Invalid = false;
582 const char *ScratchBufStart
583 = SourceMgr.getBufferData(LocFileID, &Invalid).data();
587 // Make a lexer to lex this string from. Lex just this one token.
588 // Make a lexer object so that we lex and expand the paste result.
589 Lexer TL(SourceMgr.getLocForStartOfFile(LocFileID),
590 PP.getLangOpts(), ScratchBufStart,
591 ResultTokStrPtr, ResultTokStrPtr+LHSLen+RHSLen);
593 // Lex a token in raw mode. This way it won't look up identifiers
594 // automatically, lexing off the end will return an eof token, and
595 // warnings are disabled. This returns true if the result token is the
597 bool isInvalid = !TL.LexFromRawLexer(Result);
599 // If we got an EOF token, we didn't form even ONE token. For example, we
600 // did "/ ## /" to get "//".
601 isInvalid |= Result.is(tok::eof);
603 // If pasting the two tokens didn't form a full new token, this is an
604 // error. This occurs with "x ## +" and other stuff. Return with Tok
605 // unmodified and with RHS as the next token to lex.
607 // Test for the Microsoft extension of /##/ turning into // here on the
609 if (PP.getLangOpts().MicrosoftExt && Tok.is(tok::slash) &&
610 RHS.is(tok::slash)) {
611 HandleMicrosoftCommentPaste(Tok);
615 // Do not emit the error when preprocessing assembler code.
616 if (!PP.getLangOpts().AsmPreprocessor) {
617 // Explicitly convert the token location to have proper expansion
618 // information so that the user knows where it came from.
619 SourceManager &SM = PP.getSourceManager();
621 SM.createExpansionLoc(PasteOpLoc, ExpandLocStart, ExpandLocEnd, 2);
622 // If we're in microsoft extensions mode, downgrade this from a hard
623 // error to a warning that defaults to an error. This allows
626 PP.getLangOpts().MicrosoftExt ? diag::err_pp_bad_paste_ms
627 : diag::err_pp_bad_paste)
631 // An error has occurred so exit loop.
635 // Turn ## into 'unknown' to avoid # ## # from looking like a paste
637 if (Result.is(tok::hashhash))
638 Result.setKind(tok::unknown);
641 // Transfer properties of the LHS over the Result.
642 Result.setFlagValue(Token::StartOfLine , Tok.isAtStartOfLine());
643 Result.setFlagValue(Token::LeadingSpace, Tok.hasLeadingSpace());
645 // Finally, replace LHS with the result, consume the RHS, and iterate.
648 } while (!isAtEnd() && Tokens[CurToken].is(tok::hashhash));
650 SourceLocation EndLoc = Tokens[CurToken - 1].getLocation();
652 // The token's current location indicate where the token was lexed from. We
653 // need this information to compute the spelling of the token, but any
654 // diagnostics for the expanded token should appear as if the token was
655 // expanded from the full ## expression. Pull this information together into
656 // a new SourceLocation that captures all of this.
657 SourceManager &SM = PP.getSourceManager();
658 if (StartLoc.isFileID())
659 StartLoc = getExpansionLocForMacroDefLoc(StartLoc);
660 if (EndLoc.isFileID())
661 EndLoc = getExpansionLocForMacroDefLoc(EndLoc);
662 FileID MacroFID = SM.getFileID(MacroExpansionStart);
663 while (SM.getFileID(StartLoc) != MacroFID)
664 StartLoc = SM.getImmediateExpansionRange(StartLoc).first;
665 while (SM.getFileID(EndLoc) != MacroFID)
666 EndLoc = SM.getImmediateExpansionRange(EndLoc).second;
668 Tok.setLocation(SM.createExpansionLoc(Tok.getLocation(), StartLoc, EndLoc,
671 // Now that we got the result token, it will be subject to expansion. Since
672 // token pasting re-lexes the result token in raw mode, identifier information
673 // isn't looked up. As such, if the result is an identifier, look up id info.
674 if (Tok.is(tok::raw_identifier)) {
675 // Look up the identifier info for the token. We disabled identifier lookup
676 // by saying we're skipping contents, so we need to do this manually.
677 PP.LookUpIdentifierInfo(Tok);
682 /// isNextTokenLParen - If the next token lexed will pop this macro off the
683 /// expansion stack, return 2. If the next unexpanded token is a '(', return
684 /// 1, otherwise return 0.
685 unsigned TokenLexer::isNextTokenLParen() const {
689 return Tokens[CurToken].is(tok::l_paren);
692 /// isParsingPreprocessorDirective - Return true if we are in the middle of a
693 /// preprocessor directive.
694 bool TokenLexer::isParsingPreprocessorDirective() const {
695 return Tokens[NumTokens-1].is(tok::eod) && !isAtEnd();
698 /// HandleMicrosoftCommentPaste - In microsoft compatibility mode, /##/ pastes
699 /// together to form a comment that comments out everything in the current
700 /// macro, other active macros, and anything left on the current physical
701 /// source line of the expanded buffer. Handle this by returning the
702 /// first token on the next line.
703 void TokenLexer::HandleMicrosoftCommentPaste(Token &Tok) {
704 // We 'comment out' the rest of this macro by just ignoring the rest of the
705 // tokens that have not been lexed yet, if any.
707 // Since this must be a macro, mark the macro enabled now that it is no longer
709 assert(Macro && "Token streams can't paste comments");
710 Macro->EnableMacro();
712 PP.HandleMicrosoftCommentPaste(Tok);
715 /// \brief If \arg loc is a file ID and points inside the current macro
716 /// definition, returns the appropriate source location pointing at the
717 /// macro expansion source location entry, otherwise it returns an invalid
720 TokenLexer::getExpansionLocForMacroDefLoc(SourceLocation loc) const {
721 assert(ExpandLocStart.isValid() && MacroExpansionStart.isValid() &&
722 "Not appropriate for token streams");
723 assert(loc.isValid() && loc.isFileID());
725 SourceManager &SM = PP.getSourceManager();
726 assert(SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength) &&
727 "Expected loc to come from the macro definition");
729 unsigned relativeOffset = 0;
730 SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength, &relativeOffset);
731 return MacroExpansionStart.getLocWithOffset(relativeOffset);
734 /// \brief Finds the tokens that are consecutive (from the same FileID)
735 /// creates a single SLocEntry, and assigns SourceLocations to each token that
736 /// point to that SLocEntry. e.g for
737 /// assert(foo == bar);
738 /// There will be a single SLocEntry for the "foo == bar" chunk and locations
739 /// for the 'foo', '==', 'bar' tokens will point inside that chunk.
741 /// \arg begin_tokens will be updated to a position past all the found
742 /// consecutive tokens.
743 static void updateConsecutiveMacroArgTokens(SourceManager &SM,
744 SourceLocation InstLoc,
745 Token *&begin_tokens,
746 Token * end_tokens) {
747 assert(begin_tokens < end_tokens);
749 SourceLocation FirstLoc = begin_tokens->getLocation();
750 SourceLocation CurLoc = FirstLoc;
752 // Compare the source location offset of tokens and group together tokens that
753 // are close, even if their locations point to different FileIDs. e.g.
755 // |bar | foo | cake | (3 tokens from 3 consecutive FileIDs)
757 // |bar foo cake| (one SLocEntry chunk for all tokens)
759 // we can perform this "merge" since the token's spelling location depends
760 // on the relative offset.
762 Token *NextTok = begin_tokens + 1;
763 for (; NextTok < end_tokens; ++NextTok) {
764 SourceLocation NextLoc = NextTok->getLocation();
765 if (CurLoc.isFileID() != NextLoc.isFileID())
766 break; // Token from different kind of FileID.
769 if (!SM.isInSameSLocAddrSpace(CurLoc, NextLoc, &RelOffs))
770 break; // Token from different local/loaded location.
771 // Check that token is not before the previous token or more than 50
772 // "characters" away.
773 if (RelOffs < 0 || RelOffs > 50)
778 // For the consecutive tokens, find the length of the SLocEntry to contain
780 Token &LastConsecutiveTok = *(NextTok-1);
782 SM.isInSameSLocAddrSpace(FirstLoc, LastConsecutiveTok.getLocation(),
784 unsigned FullLength = LastRelOffs + LastConsecutiveTok.getLength();
786 // Create a macro expansion SLocEntry that will "contain" all of the tokens.
787 SourceLocation Expansion =
788 SM.createMacroArgExpansionLoc(FirstLoc, InstLoc,FullLength);
790 // Change the location of the tokens from the spelling location to the new
791 // expanded location.
792 for (; begin_tokens < NextTok; ++begin_tokens) {
793 Token &Tok = *begin_tokens;
795 SM.isInSameSLocAddrSpace(FirstLoc, Tok.getLocation(), &RelOffs);
796 Tok.setLocation(Expansion.getLocWithOffset(RelOffs));
800 /// \brief Creates SLocEntries and updates the locations of macro argument
801 /// tokens to their new expanded locations.
803 /// \param ArgIdDefLoc the location of the macro argument id inside the macro
805 /// \param Tokens the macro argument tokens to update.
806 void TokenLexer::updateLocForMacroArgTokens(SourceLocation ArgIdSpellLoc,
809 SourceManager &SM = PP.getSourceManager();
811 SourceLocation InstLoc =
812 getExpansionLocForMacroDefLoc(ArgIdSpellLoc);
814 while (begin_tokens < end_tokens) {
815 // If there's only one token just create a SLocEntry for it.
816 if (end_tokens - begin_tokens == 1) {
817 Token &Tok = *begin_tokens;
818 Tok.setLocation(SM.createMacroArgExpansionLoc(Tok.getLocation(),
824 updateConsecutiveMacroArgTokens(SM, InstLoc, begin_tokens, end_tokens);
828 void TokenLexer::PropagateLineStartLeadingSpaceInfo(Token &Result) {
829 AtStartOfLine = Result.isAtStartOfLine();
830 HasLeadingSpace = Result.hasLeadingSpace();