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-rw-r--r--lib/Lex/MacroArgs.cpp240
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diff --git a/lib/Lex/MacroArgs.cpp b/lib/Lex/MacroArgs.cpp
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+//===--- TokenLexer.cpp - Lex from a token stream -------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the TokenLexer interface.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MacroArgs.h"
+#include "clang/Lex/MacroInfo.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Lex/LexDiagnostic.h"
+using namespace clang;
+
+/// MacroArgs ctor function - This destroys the vector passed in.
+MacroArgs *MacroArgs::create(const MacroInfo *MI,
+ const Token *UnexpArgTokens,
+ unsigned NumToks, bool VarargsElided) {
+ assert(MI->isFunctionLike() &&
+ "Can't have args for an object-like macro!");
+
+ // Allocate memory for the MacroArgs object with the lexer tokens at the end.
+ MacroArgs *Result = (MacroArgs*)malloc(sizeof(MacroArgs) +
+ NumToks*sizeof(Token));
+ // Construct the macroargs object.
+ new (Result) MacroArgs(NumToks, VarargsElided);
+
+ // Copy the actual unexpanded tokens to immediately after the result ptr.
+ if (NumToks)
+ memcpy(const_cast<Token*>(Result->getUnexpArgument(0)),
+ UnexpArgTokens, NumToks*sizeof(Token));
+
+ return Result;
+}
+
+/// destroy - Destroy and deallocate the memory for this object.
+///
+void MacroArgs::destroy() {
+ // Run the dtor to deallocate the vectors.
+ this->~MacroArgs();
+ // Release the memory for the object.
+ free(this);
+}
+
+
+/// getArgLength - Given a pointer to an expanded or unexpanded argument,
+/// return the number of tokens, not counting the EOF, that make up the
+/// argument.
+unsigned MacroArgs::getArgLength(const Token *ArgPtr) {
+ unsigned NumArgTokens = 0;
+ for (; ArgPtr->isNot(tok::eof); ++ArgPtr)
+ ++NumArgTokens;
+ return NumArgTokens;
+}
+
+
+/// getUnexpArgument - Return the unexpanded tokens for the specified formal.
+///
+const Token *MacroArgs::getUnexpArgument(unsigned Arg) const {
+ // The unexpanded argument tokens start immediately after the MacroArgs object
+ // in memory.
+ const Token *Start = (const Token *)(this+1);
+ const Token *Result = Start;
+ // Scan to find Arg.
+ for (; Arg; ++Result) {
+ assert(Result < Start+NumUnexpArgTokens && "Invalid arg #");
+ if (Result->is(tok::eof))
+ --Arg;
+ }
+ assert(Result < Start+NumUnexpArgTokens && "Invalid arg #");
+ return Result;
+}
+
+
+/// ArgNeedsPreexpansion - If we can prove that the argument won't be affected
+/// by pre-expansion, return false. Otherwise, conservatively return true.
+bool MacroArgs::ArgNeedsPreexpansion(const Token *ArgTok,
+ Preprocessor &PP) const {
+ // If there are no identifiers in the argument list, or if the identifiers are
+ // known to not be macros, pre-expansion won't modify it.
+ for (; ArgTok->isNot(tok::eof); ++ArgTok)
+ if (IdentifierInfo *II = ArgTok->getIdentifierInfo()) {
+ if (II->hasMacroDefinition() && PP.getMacroInfo(II)->isEnabled())
+ // Return true even though the macro could be a function-like macro
+ // without a following '(' token.
+ return true;
+ }
+ return false;
+}
+
+/// getPreExpArgument - Return the pre-expanded form of the specified
+/// argument.
+const std::vector<Token> &
+MacroArgs::getPreExpArgument(unsigned Arg, Preprocessor &PP) {
+ assert(Arg < NumUnexpArgTokens && "Invalid argument number!");
+
+ // If we have already computed this, return it.
+ if (PreExpArgTokens.empty())
+ PreExpArgTokens.resize(NumUnexpArgTokens);
+
+ std::vector<Token> &Result = PreExpArgTokens[Arg];
+ if (!Result.empty()) return Result;
+
+ const Token *AT = getUnexpArgument(Arg);
+ unsigned NumToks = getArgLength(AT)+1; // Include the EOF.
+
+ // Otherwise, we have to pre-expand this argument, populating Result. To do
+ // this, we set up a fake TokenLexer to lex from the unexpanded argument
+ // list. With this installed, we lex expanded tokens until we hit the EOF
+ // token at the end of the unexp list.
+ PP.EnterTokenStream(AT, NumToks, false /*disable expand*/,
+ false /*owns tokens*/);
+
+ // Lex all of the macro-expanded tokens into Result.
+ do {
+ Result.push_back(Token());
+ Token &Tok = Result.back();
+ PP.Lex(Tok);
+ } while (Result.back().isNot(tok::eof));
+
+ // Pop the token stream off the top of the stack. We know that the internal
+ // pointer inside of it is to the "end" of the token stream, but the stack
+ // will not otherwise be popped until the next token is lexed. The problem is
+ // that the token may be lexed sometime after the vector of tokens itself is
+ // destroyed, which would be badness.
+ PP.RemoveTopOfLexerStack();
+ return Result;
+}
+
+
+/// StringifyArgument - Implement C99 6.10.3.2p2, converting a sequence of
+/// tokens into the literal string token that should be produced by the C #
+/// preprocessor operator. If Charify is true, then it should be turned into
+/// a character literal for the Microsoft charize (#@) extension.
+///
+Token MacroArgs::StringifyArgument(const Token *ArgToks,
+ Preprocessor &PP, bool Charify) {
+ Token Tok;
+ Tok.startToken();
+ Tok.setKind(tok::string_literal);
+
+ const Token *ArgTokStart = ArgToks;
+
+ // Stringify all the tokens.
+ llvm::SmallString<128> Result;
+ Result += "\"";
+
+ bool isFirst = true;
+ for (; ArgToks->isNot(tok::eof); ++ArgToks) {
+ const Token &Tok = *ArgToks;
+ if (!isFirst && (Tok.hasLeadingSpace() || Tok.isAtStartOfLine()))
+ Result += ' ';
+ isFirst = false;
+
+ // If this is a string or character constant, escape the token as specified
+ // by 6.10.3.2p2.
+ if (Tok.is(tok::string_literal) || // "foo"
+ Tok.is(tok::wide_string_literal) || // L"foo"
+ Tok.is(tok::char_constant)) { // 'x' and L'x'.
+ std::string Str = Lexer::Stringify(PP.getSpelling(Tok));
+ Result.append(Str.begin(), Str.end());
+ } else {
+ // Otherwise, just append the token. Do some gymnastics to get the token
+ // in place and avoid copies where possible.
+ unsigned CurStrLen = Result.size();
+ Result.resize(CurStrLen+Tok.getLength());
+ const char *BufPtr = &Result[CurStrLen];
+ unsigned ActualTokLen = PP.getSpelling(Tok, BufPtr);
+
+ // If getSpelling returned a pointer to an already uniqued version of the
+ // string instead of filling in BufPtr, memcpy it onto our string.
+ if (BufPtr != &Result[CurStrLen])
+ memcpy(&Result[CurStrLen], BufPtr, ActualTokLen);
+
+ // If the token was dirty, the spelling may be shorter than the token.
+ if (ActualTokLen != Tok.getLength())
+ Result.resize(CurStrLen+ActualTokLen);
+ }
+ }
+
+ // If the last character of the string is a \, and if it isn't escaped, this
+ // is an invalid string literal, diagnose it as specified in C99.
+ if (Result.back() == '\\') {
+ // Count the number of consequtive \ characters. If even, then they are
+ // just escaped backslashes, otherwise it's an error.
+ unsigned FirstNonSlash = Result.size()-2;
+ // Guaranteed to find the starting " if nothing else.
+ while (Result[FirstNonSlash] == '\\')
+ --FirstNonSlash;
+ if ((Result.size()-1-FirstNonSlash) & 1) {
+ // Diagnose errors for things like: #define F(X) #X / F(\)
+ PP.Diag(ArgToks[-1], diag::pp_invalid_string_literal);
+ Result.pop_back(); // remove one of the \'s.
+ }
+ }
+ Result += '"';
+
+ // If this is the charify operation and the result is not a legal character
+ // constant, diagnose it.
+ if (Charify) {
+ // First step, turn double quotes into single quotes:
+ Result[0] = '\'';
+ Result[Result.size()-1] = '\'';
+
+ // Check for bogus character.
+ bool isBad = false;
+ if (Result.size() == 3)
+ isBad = Result[1] == '\''; // ''' is not legal. '\' already fixed above.
+ else
+ isBad = (Result.size() != 4 || Result[1] != '\\'); // Not '\x'
+
+ if (isBad) {
+ PP.Diag(ArgTokStart[0], diag::err_invalid_character_to_charify);
+ Result = "' '"; // Use something arbitrary, but legal.
+ }
+ }
+
+ PP.CreateString(&Result[0], Result.size(), Tok);
+ return Tok;
+}
+
+/// getStringifiedArgument - Compute, cache, and return the specified argument
+/// that has been 'stringified' as required by the # operator.
+const Token &MacroArgs::getStringifiedArgument(unsigned ArgNo,
+ Preprocessor &PP) {
+ assert(ArgNo < NumUnexpArgTokens && "Invalid argument number!");
+ if (StringifiedArgs.empty()) {
+ StringifiedArgs.resize(getNumArguments());
+ memset(&StringifiedArgs[0], 0,
+ sizeof(StringifiedArgs[0])*getNumArguments());
+ }
+ if (StringifiedArgs[ArgNo].isNot(tok::string_literal))
+ StringifiedArgs[ArgNo] = StringifyArgument(getUnexpArgument(ArgNo), PP);
+ return StringifiedArgs[ArgNo];
+}
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