695 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			695 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
//===--- MacroExpander.cpp - Lex from a macro expansion -------------------===//
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//
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//                     The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the MacroExpander interface.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/Lex/MacroExpander.h"
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#include "clang/Lex/MacroInfo.h"
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#include "clang/Lex/Preprocessor.h"
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#include "clang/Basic/SourceManager.h"
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#include "clang/Basic/Diagnostic.h"
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#include "llvm/ADT/SmallVector.h"
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using namespace clang;
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//===----------------------------------------------------------------------===//
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// MacroArgs Implementation
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//===----------------------------------------------------------------------===//
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/// MacroArgs ctor function - This destroys the vector passed in.
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MacroArgs *MacroArgs::create(const MacroInfo *MI,
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                             const Token *UnexpArgTokens,
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                             unsigned NumToks, bool VarargsElided) {
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  assert(MI->isFunctionLike() &&
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         "Can't have args for an object-like macro!");
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  // Allocate memory for the MacroArgs object with the lexer tokens at the end.
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  MacroArgs *Result = (MacroArgs*)malloc(sizeof(MacroArgs) +
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                                         NumToks*sizeof(Token));
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  // Construct the macroargs object.
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  new (Result) MacroArgs(NumToks, VarargsElided);
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  // Copy the actual unexpanded tokens to immediately after the result ptr.
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  if (NumToks)
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    memcpy(const_cast<Token*>(Result->getUnexpArgument(0)),
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           UnexpArgTokens, NumToks*sizeof(Token));
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  return Result;
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}
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/// destroy - Destroy and deallocate the memory for this object.
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///
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void MacroArgs::destroy() {
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  // Run the dtor to deallocate the vectors.
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  this->~MacroArgs();
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  // Release the memory for the object.
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  free(this);
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}
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/// getArgLength - Given a pointer to an expanded or unexpanded argument,
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/// return the number of tokens, not counting the EOF, that make up the
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/// argument.
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unsigned MacroArgs::getArgLength(const Token *ArgPtr) {
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  unsigned NumArgTokens = 0;
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  for (; ArgPtr->isNot(tok::eof); ++ArgPtr)
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    ++NumArgTokens;
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  return NumArgTokens;
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}
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/// getUnexpArgument - Return the unexpanded tokens for the specified formal.
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///
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const Token *MacroArgs::getUnexpArgument(unsigned Arg) const {
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  // The unexpanded argument tokens start immediately after the MacroArgs object
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  // in memory.
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  const Token *Start = (const Token *)(this+1);
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  const Token *Result = Start;
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  // Scan to find Arg.
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  for (; Arg; ++Result) {
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    assert(Result < Start+NumUnexpArgTokens && "Invalid arg #");
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    if (Result->is(tok::eof))
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      --Arg;
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  }
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  return Result;
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}
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/// ArgNeedsPreexpansion - If we can prove that the argument won't be affected
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/// by pre-expansion, return false.  Otherwise, conservatively return true.
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bool MacroArgs::ArgNeedsPreexpansion(const Token *ArgTok,
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                                     Preprocessor &PP) const {
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  // If there are no identifiers in the argument list, or if the identifiers are
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  // known to not be macros, pre-expansion won't modify it.
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  for (; ArgTok->isNot(tok::eof); ++ArgTok)
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    if (IdentifierInfo *II = ArgTok->getIdentifierInfo()) {
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      if (II->hasMacroDefinition() && PP.getMacroInfo(II)->isEnabled())
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        // Return true even though the macro could be a function-like macro
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        // without a following '(' token.
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        return true;
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    }
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  return false;
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}
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/// getPreExpArgument - Return the pre-expanded form of the specified
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/// argument.
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const std::vector<Token> &
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MacroArgs::getPreExpArgument(unsigned Arg, Preprocessor &PP) {
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  assert(Arg < NumUnexpArgTokens && "Invalid argument number!");
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  // If we have already computed this, return it.
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  if (PreExpArgTokens.empty())
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    PreExpArgTokens.resize(NumUnexpArgTokens);
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  std::vector<Token> &Result = PreExpArgTokens[Arg];
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  if (!Result.empty()) return Result;
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  const Token *AT = getUnexpArgument(Arg);
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  unsigned NumToks = getArgLength(AT)+1;  // Include the EOF.
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  // Otherwise, we have to pre-expand this argument, populating Result.  To do
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  // this, we set up a fake MacroExpander to lex from the unexpanded argument
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  // list.  With this installed, we lex expanded tokens until we hit the EOF
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  // token at the end of the unexp list.
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  PP.EnterTokenStream(AT, NumToks);
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  // Lex all of the macro-expanded tokens into Result.
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  do {
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    Result.push_back(Token());
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    PP.Lex(Result.back());
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  } while (Result.back().isNot(tok::eof));
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  // Pop the token stream off the top of the stack.  We know that the internal
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  // pointer inside of it is to the "end" of the token stream, but the stack
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  // will not otherwise be popped until the next token is lexed.  The problem is
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  // that the token may be lexed sometime after the vector of tokens itself is
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  // destroyed, which would be badness.
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  PP.RemoveTopOfLexerStack();
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  return Result;
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}
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/// StringifyArgument - Implement C99 6.10.3.2p2, converting a sequence of
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/// tokens into the literal string token that should be produced by the C #
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/// preprocessor operator.
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///
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static Token StringifyArgument(const Token *ArgToks,
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                                    Preprocessor &PP, bool Charify = false) {
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  Token Tok;
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  Tok.startToken();
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  Tok.setKind(tok::string_literal);
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  const Token *ArgTokStart = ArgToks;
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  // Stringify all the tokens.
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  std::string Result = "\"";
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  // FIXME: Optimize this loop to not use std::strings.
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  bool isFirst = true;
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  for (; ArgToks->isNot(tok::eof); ++ArgToks) {
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    const Token &Tok = *ArgToks;
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    if (!isFirst && (Tok.hasLeadingSpace() || Tok.isAtStartOfLine()))
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      Result += ' ';
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    isFirst = false;
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    // If this is a string or character constant, escape the token as specified
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    // by 6.10.3.2p2.
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    if (Tok.is(tok::string_literal) ||       // "foo"
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        Tok.is(tok::wide_string_literal) ||  // L"foo"
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        Tok.is(tok::char_constant)) {        // 'x' and L'x'.
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      Result += Lexer::Stringify(PP.getSpelling(Tok));
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    } else {
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      // Otherwise, just append the token.
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      Result += PP.getSpelling(Tok);
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    }
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  }
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  // If the last character of the string is a \, and if it isn't escaped, this
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  // is an invalid string literal, diagnose it as specified in C99.
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  if (Result[Result.size()-1] == '\\') {
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    // Count the number of consequtive \ characters.  If even, then they are
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    // just escaped backslashes, otherwise it's an error.
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    unsigned FirstNonSlash = Result.size()-2;
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    // Guaranteed to find the starting " if nothing else.
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    while (Result[FirstNonSlash] == '\\')
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      --FirstNonSlash;
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    if ((Result.size()-1-FirstNonSlash) & 1) {
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      // Diagnose errors for things like: #define F(X) #X   /   F(\)
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      PP.Diag(ArgToks[-1], diag::pp_invalid_string_literal);
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      Result.erase(Result.end()-1);  // remove one of the \'s.
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    }
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  }
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  Result += '"';
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  // If this is the charify operation and the result is not a legal character
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  // constant, diagnose it.
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  if (Charify) {
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    // First step, turn double quotes into single quotes:
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    Result[0] = '\'';
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    Result[Result.size()-1] = '\'';
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    // Check for bogus character.
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    bool isBad = false;
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    if (Result.size() == 3) {
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      isBad = Result[1] == '\'';   // ''' is not legal. '\' already fixed above.
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    } else {
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      isBad = (Result.size() != 4 || Result[1] != '\\');  // Not '\x'
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    }
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    if (isBad) {
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      PP.Diag(ArgTokStart[0], diag::err_invalid_character_to_charify);
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      Result = "' '";  // Use something arbitrary, but legal.
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    }
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  }
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  Tok.setLength(Result.size());
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  Tok.setLocation(PP.CreateString(&Result[0], Result.size()));
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  return Tok;
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}
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/// getStringifiedArgument - Compute, cache, and return the specified argument
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/// that has been 'stringified' as required by the # operator.
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const Token &MacroArgs::getStringifiedArgument(unsigned ArgNo,
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                                                    Preprocessor &PP) {
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  assert(ArgNo < NumUnexpArgTokens && "Invalid argument number!");
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  if (StringifiedArgs.empty()) {
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    StringifiedArgs.resize(getNumArguments());
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    memset(&StringifiedArgs[0], 0,
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           sizeof(StringifiedArgs[0])*getNumArguments());
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  }
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  if (StringifiedArgs[ArgNo].isNot(tok::string_literal))
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    StringifiedArgs[ArgNo] = StringifyArgument(getUnexpArgument(ArgNo), PP);
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  return StringifiedArgs[ArgNo];
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}
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//===----------------------------------------------------------------------===//
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// MacroExpander Implementation
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//===----------------------------------------------------------------------===//
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/// Create a macro expander for the specified macro with the specified actual
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/// arguments.  Note that this ctor takes ownership of the ActualArgs pointer.
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void MacroExpander::Init(Token &Tok, MacroArgs *Actuals) {
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  // If the client is reusing a macro expander, make sure to free any memory
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  // associated with it.
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  destroy();
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  Macro = PP.getMacroInfo(Tok.getIdentifierInfo());
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  ActualArgs = Actuals;
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  CurToken = 0;
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  InstantiateLoc = Tok.getLocation();
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  AtStartOfLine = Tok.isAtStartOfLine();
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  HasLeadingSpace = Tok.hasLeadingSpace();
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  MacroTokens = &*Macro->tokens_begin();
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  OwnsMacroTokens = false;
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  NumMacroTokens = Macro->tokens_end()-Macro->tokens_begin();
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  // If this is a function-like macro, expand the arguments and change
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  // MacroTokens to point to the expanded tokens.
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  if (Macro->isFunctionLike() && Macro->getNumArgs())
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    ExpandFunctionArguments();
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  // Mark the macro as currently disabled, so that it is not recursively
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  // expanded.  The macro must be disabled only after argument pre-expansion of
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  // function-like macro arguments occurs.
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  Macro->DisableMacro();
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}
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/// Create a macro expander for the specified token stream.  This does not
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/// take ownership of the specified token vector.
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void MacroExpander::Init(const Token *TokArray, unsigned NumToks) {
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  // If the client is reusing a macro expander, make sure to free any memory
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  // associated with it.
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  destroy();
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  Macro = 0;
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  ActualArgs = 0;
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  MacroTokens = TokArray;
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  OwnsMacroTokens = false;
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  NumMacroTokens = NumToks;
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  CurToken = 0;
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  InstantiateLoc = SourceLocation();
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  AtStartOfLine = false;
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  HasLeadingSpace = false;
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  // Set HasLeadingSpace/AtStartOfLine so that the first token will be
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  // returned unmodified.
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  if (NumToks != 0) {
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    AtStartOfLine   = TokArray[0].isAtStartOfLine();
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    HasLeadingSpace = TokArray[0].hasLeadingSpace();
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  }
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}
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void MacroExpander::destroy() {
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  // If this was a function-like macro that actually uses its arguments, delete
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  // the expanded tokens.
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  if (OwnsMacroTokens) {
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    delete [] MacroTokens;
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    MacroTokens = 0;
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  }
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  // MacroExpander owns its formal arguments.
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  if (ActualArgs) ActualArgs->destroy();
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}
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/// Expand the arguments of a function-like macro so that we can quickly
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/// return preexpanded tokens from MacroTokens.
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void MacroExpander::ExpandFunctionArguments() {
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  llvm::SmallVector<Token, 128> ResultToks;
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  // Loop through the MacroTokens tokens, expanding them into ResultToks.  Keep
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  // track of whether we change anything.  If not, no need to keep them.  If so,
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  // we install the newly expanded sequence as MacroTokens.
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  bool MadeChange = false;
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  // NextTokGetsSpace - When this is true, the next token appended to the
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  // output list will get a leading space, regardless of whether it had one to
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  // begin with or not.  This is used for placemarker support.
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  bool NextTokGetsSpace = false;
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  for (unsigned i = 0, e = NumMacroTokens; i != e; ++i) {
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    // If we found the stringify operator, get the argument stringified.  The
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    // preprocessor already verified that the following token is a macro name
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    // when the #define was parsed.
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    const Token &CurTok = MacroTokens[i];
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    if (CurTok.is(tok::hash) || CurTok.is(tok::hashat)) {
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      int ArgNo = Macro->getArgumentNum(MacroTokens[i+1].getIdentifierInfo());
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      assert(ArgNo != -1 && "Token following # is not an argument?");
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      Token Res;
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      if (CurTok.is(tok::hash))  // Stringify
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        Res = ActualArgs->getStringifiedArgument(ArgNo, PP);
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      else {
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        // 'charify': don't bother caching these.
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        Res = StringifyArgument(ActualArgs->getUnexpArgument(ArgNo), PP, true);
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      }
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      // The stringified/charified string leading space flag gets set to match
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      // the #/#@ operator.
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      if (CurTok.hasLeadingSpace() || NextTokGetsSpace)
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        Res.setFlag(Token::LeadingSpace);
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      ResultToks.push_back(Res);
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      MadeChange = true;
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      ++i;  // Skip arg name.
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      NextTokGetsSpace = false;
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      continue;
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    }
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    // Otherwise, if this is not an argument token, just add the token to the
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    // output buffer.
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    IdentifierInfo *II = CurTok.getIdentifierInfo();
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    int ArgNo = II ? Macro->getArgumentNum(II) : -1;
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    if (ArgNo == -1) {
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      // This isn't an argument, just add it.
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      ResultToks.push_back(CurTok);
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      if (NextTokGetsSpace) {
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        ResultToks.back().setFlag(Token::LeadingSpace);
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        NextTokGetsSpace = false;
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      }
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      continue;
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    }
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    // An argument is expanded somehow, the result is different than the
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    // input.
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    MadeChange = true;
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    // Otherwise, this is a use of the argument.  Find out if there is a paste
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    // (##) operator before or after the argument.
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    bool PasteBefore = 
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      !ResultToks.empty() && ResultToks.back().is(tok::hashhash);
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    bool PasteAfter = i+1 != e && MacroTokens[i+1].is(tok::hashhash);
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    // If it is not the LHS/RHS of a ## operator, we must pre-expand the
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    // argument and substitute the expanded tokens into the result.  This is
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    // C99 6.10.3.1p1.
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    if (!PasteBefore && !PasteAfter) {
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      const Token *ResultArgToks;
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      // Only preexpand the argument if it could possibly need it.  This
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      // avoids some work in common cases.
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      const Token *ArgTok = ActualArgs->getUnexpArgument(ArgNo);
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      if (ActualArgs->ArgNeedsPreexpansion(ArgTok, PP))
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        ResultArgToks = &ActualArgs->getPreExpArgument(ArgNo, PP)[0];
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      else
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        ResultArgToks = ArgTok;  // Use non-preexpanded tokens.
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      // If the arg token expanded into anything, append it.
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      if (ResultArgToks->isNot(tok::eof)) {
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        unsigned FirstResult = ResultToks.size();
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        unsigned NumToks = MacroArgs::getArgLength(ResultArgToks);
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        ResultToks.append(ResultArgToks, ResultArgToks+NumToks);
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        // If any tokens were substituted from the argument, the whitespace
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        // before the first token should match the whitespace of the arg
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        // identifier.
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        ResultToks[FirstResult].setFlagValue(Token::LeadingSpace,
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                                             CurTok.hasLeadingSpace() ||
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                                             NextTokGetsSpace);
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        NextTokGetsSpace = false;
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      } else {
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        // If this is an empty argument, and if there was whitespace before the
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        // formal token, make sure the next token gets whitespace before it.
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        NextTokGetsSpace = CurTok.hasLeadingSpace();
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      }
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      continue;
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    }
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    // Okay, we have a token that is either the LHS or RHS of a paste (##)
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    // argument.  It gets substituted as its non-pre-expanded tokens.
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    const Token *ArgToks = ActualArgs->getUnexpArgument(ArgNo);
 | 
						|
    unsigned NumToks = MacroArgs::getArgLength(ArgToks);
 | 
						|
    if (NumToks) {  // Not an empty argument?
 | 
						|
      // If this is the GNU ", ## __VA_ARG__" extension, and we just learned
 | 
						|
      // that __VA_ARG__ expands to multiple tokens, avoid a pasting error when
 | 
						|
      // the expander trys to paste ',' with the first token of the __VA_ARG__
 | 
						|
      // 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 next token was supposed to get leading whitespace, ensure it has
 | 
						|
      // it now.
 | 
						|
      if (NextTokGetsSpace) {
 | 
						|
        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 |= MacroTokens[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();
 | 
						|
    }
 | 
						|
    continue;
 | 
						|
  }
 | 
						|
  
 | 
						|
  // If anything changed, install this as the new MacroTokens list.
 | 
						|
  if (MadeChange) {
 | 
						|
    // This is deleted in the dtor.
 | 
						|
    NumMacroTokens = ResultToks.size();
 | 
						|
    Token *Res = new Token[ResultToks.size()];
 | 
						|
    if (NumMacroTokens)
 | 
						|
      memcpy(Res, &ResultToks[0], NumMacroTokens*sizeof(Token));
 | 
						|
    MacroTokens = Res;
 | 
						|
    OwnsMacroTokens = true;
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
/// Lex - Lex and return a token from this macro stream.
 | 
						|
///
 | 
						|
void MacroExpander::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.HandleEndOfMacro(Tok))
 | 
						|
      return;
 | 
						|
 | 
						|
    // HandleEndOfMacro may not return a token.  If it doesn't, lex whatever is
 | 
						|
    // next.
 | 
						|
    return PPCache.Lex(Tok);
 | 
						|
  }
 | 
						|
  
 | 
						|
  // 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 = MacroTokens[CurToken++];
 | 
						|
  
 | 
						|
  // If this token is followed by a token paste (##) operator, paste the tokens!
 | 
						|
  if (!isAtEnd() && MacroTokens[CurToken].is(tok::hashhash))
 | 
						|
    if (PasteTokens(Tok)) {
 | 
						|
      // When handling the microsoft /##/ extension, the final token is
 | 
						|
      // returned by PasteTokens, not the pasted token.
 | 
						|
      return;
 | 
						|
    }
 | 
						|
 | 
						|
  // 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
 | 
						|
  // InstantiationLoc.  Pull this information together into a new SourceLocation
 | 
						|
  // that captures all of this.
 | 
						|
  if (InstantiateLoc.isValid()) {   // Don't do this for token streams.
 | 
						|
    SourceManager &SrcMgr = PP.getSourceManager();
 | 
						|
    Tok.setLocation(SrcMgr.getInstantiationLoc(Tok.getLocation(), 
 | 
						|
                                               InstantiateLoc));
 | 
						|
  }
 | 
						|
  
 | 
						|
  // 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.getIdentifierInfo())
 | 
						|
    return 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 is another ## after it, chomp it iteratively.  Return the result as Tok.
 | 
						|
/// If this returns true, the caller should immediately return the token.
 | 
						|
bool MacroExpander::PasteTokens(Token &Tok) {
 | 
						|
  llvm::SmallVector<char, 128> Buffer;
 | 
						|
  do {
 | 
						|
    // Consume the ## operator.
 | 
						|
    SourceLocation PasteOpLoc = MacroTokens[CurToken].getLocation();
 | 
						|
    ++CurToken;
 | 
						|
    assert(!isAtEnd() && "No token on the RHS of a paste operator!");
 | 
						|
  
 | 
						|
    // Get the RHS token.
 | 
						|
    const Token &RHS = MacroTokens[CurToken];
 | 
						|
  
 | 
						|
    bool isInvalid = false;
 | 
						|
 | 
						|
    // Allocate space for the result token.  This is guaranteed to be enough for
 | 
						|
    // the two tokens and a null terminator.
 | 
						|
    Buffer.resize(Tok.getLength() + RHS.getLength() + 1);
 | 
						|
    
 | 
						|
    // Get the spelling of the LHS token in Buffer.
 | 
						|
    const char *BufPtr = &Buffer[0];
 | 
						|
    unsigned LHSLen = PP.getSpelling(Tok, BufPtr);
 | 
						|
    if (BufPtr != &Buffer[0])   // Really, we want the chars in Buffer!
 | 
						|
      memcpy(&Buffer[0], BufPtr, LHSLen);
 | 
						|
    
 | 
						|
    BufPtr = &Buffer[LHSLen];
 | 
						|
    unsigned RHSLen = PP.getSpelling(RHS, BufPtr);
 | 
						|
    if (BufPtr != &Buffer[LHSLen])   // Really, we want the chars in Buffer!
 | 
						|
      memcpy(&Buffer[LHSLen], BufPtr, RHSLen);
 | 
						|
    
 | 
						|
    // Add null terminator.
 | 
						|
    Buffer[LHSLen+RHSLen] = '\0';
 | 
						|
    
 | 
						|
    // Trim excess space.
 | 
						|
    Buffer.resize(LHSLen+RHSLen+1);
 | 
						|
    
 | 
						|
    // Plop the pasted result (including the trailing newline and null) into a
 | 
						|
    // scratch buffer where we can lex it.
 | 
						|
    SourceLocation ResultTokLoc = PP.CreateString(&Buffer[0], Buffer.size());
 | 
						|
    
 | 
						|
    // Lex the resultant pasted token into Result.
 | 
						|
    Token Result;
 | 
						|
    
 | 
						|
    // Avoid testing /*, as the lexer would think it is the start of a comment
 | 
						|
    // and emit an error that it is unterminated.
 | 
						|
    if (Tok.is(tok::slash) && RHS.is(tok::star)) {
 | 
						|
      isInvalid = true;
 | 
						|
    } else if (Tok.is(tok::identifier) && RHS.is(tok::identifier)) {
 | 
						|
      // Common paste case: identifier+identifier = identifier.  Avoid creating
 | 
						|
      // a lexer and other overhead.
 | 
						|
      PP.IncrementPasteCounter(true);
 | 
						|
      Result.startToken();
 | 
						|
      Result.setKind(tok::identifier);
 | 
						|
      Result.setLocation(ResultTokLoc);
 | 
						|
      Result.setLength(LHSLen+RHSLen);
 | 
						|
    } else {
 | 
						|
      PP.IncrementPasteCounter(false);
 | 
						|
      
 | 
						|
      // Make a lexer to lex this string from.
 | 
						|
      SourceManager &SourceMgr = PP.getSourceManager();
 | 
						|
      const char *ResultStrData = SourceMgr.getCharacterData(ResultTokLoc);
 | 
						|
      
 | 
						|
      // Make a lexer object so that we lex and expand the paste result.
 | 
						|
      Lexer *TL = new Lexer(ResultTokLoc, PP, ResultStrData, 
 | 
						|
                            ResultStrData+LHSLen+RHSLen /*don't include null*/);
 | 
						|
      
 | 
						|
      // 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 IsComplete = TL->LexRawToken(Result);
 | 
						|
      
 | 
						|
      // If we got an EOF token, we didn't form even ONE token.  For example, we
 | 
						|
      // did "/ ## /" to get "//".
 | 
						|
      IsComplete &= Result.isNot(tok::eof);
 | 
						|
      isInvalid = !IsComplete;
 | 
						|
      
 | 
						|
      // We're now done with the temporary lexer.
 | 
						|
      delete TL;
 | 
						|
    }
 | 
						|
    
 | 
						|
    // 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.getLangOptions().Microsoft && Tok.is(tok::slash) && 
 | 
						|
          RHS.is(tok::slash)) {
 | 
						|
        HandleMicrosoftCommentPaste(Tok);
 | 
						|
        return true;
 | 
						|
      } else {
 | 
						|
        // TODO: If not in assembler language mode.
 | 
						|
        PP.Diag(PasteOpLoc, diag::err_pp_bad_paste, 
 | 
						|
                std::string(Buffer.begin(), Buffer.end()-1));
 | 
						|
        return false;
 | 
						|
      }
 | 
						|
    }
 | 
						|
    
 | 
						|
    // Turn ## into 'other' to avoid # ## # from looking like a paste operator.
 | 
						|
    if (Result.is(tok::hashhash))
 | 
						|
      Result.setKind(tok::unknown);
 | 
						|
    // FIXME: Turn __VA_ARGS__ into "not a token"?
 | 
						|
    
 | 
						|
    // Transfer properties of the LHS over the 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() && MacroTokens[CurToken].is(tok::hashhash));
 | 
						|
  
 | 
						|
  // 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::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.
 | 
						|
    Tok.setIdentifierInfo(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 MacroExpander::isNextTokenLParen() const {
 | 
						|
  // Out of tokens?
 | 
						|
  if (isAtEnd())
 | 
						|
    return 2;
 | 
						|
  return MacroTokens[CurToken].is(tok::l_paren);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// 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 instantiated buffer.  Handle this by returning the
 | 
						|
/// first token on the next line.
 | 
						|
void MacroExpander::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);
 | 
						|
}
 |