Date:	Mon, 10 May 1999 21:54:55 +0200
To:	pgcc AT delorie DOT com
Subject:	Re: Optimization question
Message-ID:	<19990510215455.E22062@cerebro.laendle>
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In-Reply-To:	<14135.5025.220697.966833@lrz.de>; from Eugene Leitl on Mon, May 10, 1999 at 10:14:14AM -0700
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From:	Marc Lehmann <pcg AT goof DOT com>
Reply-To:	pgcc AT delorie DOT com
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On Mon, May 10, 1999 at 10:14:14AM -0700, Eugene Leitl wrote:
>  > good compilers should optimize such expressions by itself, the method is
>  > called "common subexpression optimization".
> 
> Historically, this has never worked very well.

?????

> Also, I'm wary of software which attempts to act intelligently but
> isn't.

This has nothing to do with intellgence - the language (C in this example)
defines which rules are ok and which are a no-no. Fortran allows much more
freedom for example.

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