[cfe-commits] r138704 - in /cfe/trunk: include/clang/Basic/IdentifierTable.h include/clang/Lex/Preprocessor.h lib/Lex/Preprocessor.cpp test/Modules/lookup.cpp

[Argyrios Kyrtzidis]

On Aug 26, 2011, at 11:37 PM, Douglas Gregor wrote:

> Author: dgregor
> Date: Sat Aug 27 01:37:51 2011
> New Revision: 138704
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=138704&view=rev
> Log:
> Take an entirely different approach to handling the "parsing" of
> __import__ within the preprocessor, since the prior one foolishly
> assumed that Preprocessor::Lex() was re-entrant. We now handle
> __import__ at the top level (only), after macro expansion. This should
> fix the buildbot failures.
> 

[...]

>   /// Lex - To lex a token from the preprocessor, just pull a token from the
>   /// current lexer or macro object.
>   void Lex(Token &Result) {
> +    ++LexDepth;
>     if (CurLexer)
>       CurLexer->Lex(Result);
>     else if (CurPTHLexer)
> @@ -539,6 +543,11 @@
>       CurTokenLexer->Lex(Result);
>     else
>       CachingLex(Result);
> +    --LexDepth;
> +    
> +    // If we have the __import__ keyword, handle the module import now.
> +    if (Result.getKind() == tok::kw___import__ && LexDepth == 0)
> +      HandleModuleImport(Result);
>   }

Lex() is one of those super hot methods, is it possible to avoid this modification ? I get about -5.5% for -Eonly of Cocoa.h if I remove the additions in Lex().

-Argyrios