Date: Tue, 11 May 1999 00:41:13 +0200
To: David Whysong <dwhysong AT physics DOT ucsb DOT edu>
Cc: Marc Lehmann <pcg AT goof DOT com>, pgcc AT delorie DOT com
Subject: Re: Optimization question
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	Marc Lehmann <pcg AT goof DOT com>, pgcc AT delorie DOT com
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In-Reply-To: <Pine.LNX.4.04.9905101436230.15547-100000@sal.physics.ucsb.edu>; from David Whysong on Mon, May 10, 1999 at 03:34:44PM -0700
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From: Marc Lehmann <pcg AT goof DOT com>
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On Mon, May 10, 1999 at 03:34:44PM -0700, David Whysong wrote:
> Theory doesn't seem to fit the data very well then. :-) I have gained
> nearly a factor of two in speed after doing some CSE by hand. Even on the
> simple code fragment I posted, a little "hand optimizing" significantly
> reduced the number of fmul ops. As far as I can see, very little or no CSE
> was being done at all.

Have you benchmarked it? fmuls are not really slower than fadds, for
example.  However, if you can manage to get a (sensibly sized ;) example
of where cse fails I'd be happy to look into it!


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