forked from OSchip/llvm-project
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);
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unsigned NumToks = MacroArgs::getArgLength(ArgToks);
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if (NumToks) { // Not an empty argument?
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// If this is the GNU ", ## __VA_ARG__" extension, and we just learned
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// that __VA_ARG__ expands to multiple tokens, avoid a pasting error when
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// the expander trys to paste ',' with the first token of the __VA_ARG__
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// expansion.
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if (PasteBefore && ResultToks.size() >= 2 &&
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ResultToks[ResultToks.size()-2].is(tok::comma) &&
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(unsigned)ArgNo == Macro->getNumArgs()-1 &&
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Macro->isVariadic()) {
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// Remove the paste operator, report use of the extension.
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PP.Diag(ResultToks.back().getLocation(), diag::ext_paste_comma);
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ResultToks.pop_back();
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}
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ResultToks.append(ArgToks, ArgToks+NumToks);
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// If the next token was supposed to get leading whitespace, ensure it has
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// it now.
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if (NextTokGetsSpace) {
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ResultToks[ResultToks.size()-NumToks].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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// If an empty argument is on the LHS or RHS of a paste, the standard (C99
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// 6.10.3.3p2,3) calls for a bunch of placemarker stuff to occur. We
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// implement this by eating ## operators when a LHS or RHS expands to
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// empty.
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NextTokGetsSpace |= CurTok.hasLeadingSpace();
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if (PasteAfter) {
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// Discard the argument token and skip (don't copy to the expansion
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// buffer) the paste operator after it.
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NextTokGetsSpace |= MacroTokens[i+1].hasLeadingSpace();
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++i;
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continue;
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}
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// If this is on the RHS of a paste operator, we've already copied the
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// paste operator to the ResultToks list. Remove it.
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assert(PasteBefore && ResultToks.back().is(tok::hashhash));
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NextTokGetsSpace |= ResultToks.back().hasLeadingSpace();
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ResultToks.pop_back();
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// If this is the __VA_ARGS__ token, and if the argument wasn't provided,
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// and if the macro had at least one real argument, and if the token before
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// the ## was a comma, remove the comma.
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if ((unsigned)ArgNo == Macro->getNumArgs()-1 && // is __VA_ARGS__
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ActualArgs->isVarargsElidedUse() && // Argument elided.
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!ResultToks.empty() && ResultToks.back().is(tok::comma)) {
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// Never add a space, even if the comma, ##, or arg had a space.
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NextTokGetsSpace = false;
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// Remove the paste operator, report use of the extension.
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PP.Diag(ResultToks.back().getLocation(), diag::ext_paste_comma);
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ResultToks.pop_back();
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}
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continue;
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}
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// If anything changed, install this as the new MacroTokens list.
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if (MadeChange) {
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// This is deleted in the dtor.
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NumMacroTokens = ResultToks.size();
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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);
|
|
}
|