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Re: [PATCH/RFC] Use powi as canonical form for x*x
- From: Andrew Pinski <pinskia at physics dot uc dot edu>
- To: Richard Guenther <rguenth at tat dot physik dot uni-tuebingen dot de>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Mon, 14 Mar 2005 17:02:36 -0500
- Subject: Re: [PATCH/RFC] Use powi as canonical form for x*x
- References: <423608BC.9000506@tat.physik.uni-tuebingen.de>
On Mar 14, 2005, at 4:57 PM, Richard Guenther wrote:
This patch uses powi for canonicalization of multiplication chains
rather than pow. It also moves this transformations from
unsafe-math-optimization to default. This is of course the
questionable
part of the patch. Is it f.i. ok to transform x*x*x*x to y=x*x, y*y?
I.e. with this patch we may reduce the number of multiplications.
No.
-- Pinski