From:	"sl" <junk AT bbs DOT darktech DOT org>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: GCC optimization
Date:	Thu, 30 Dec 1999 20:09:46 -0500 (EST)
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On Thu, 30 Dec 1999 16:39:28 GMT, Andrew Jones wrote:

>> Does GCC optimize "something*1024" into "something << 10"?
>
>Let's see.
>
>
>TEST.C
>~~~~
>int glob;
>
>int main(void)
>  {
>  return(glob * 1024);
>  }
>
>
>gcc -c -S test.c
>
>
>GLOB.S
>~~~~~
>[...]
>movl _glob,%eax
>movl %eax,%edx
>movl %edx,%ecx
>sall $10,%ecx
>movl %ecx,%eax
>[...]
>
>In a word: YES.

	Hehehe.. Thanks!

Gili

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