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Re: GCC beaten by ICC in stupid trig test!

From: Bradley Lucier <lucier at math dot purdue dot edu>
To: joe dot buck at synopsys dot com
Cc: roger at eyesopen dot com, gdr at integrable-solutions dot net, gcc at gcc dot gnu dot org, abraham at dina dot kvl dot dk, Bradley Lucier <lucier at math dot purdue dot edu>, gcc-patches at gcc dot gnu dot org, toon at moene dot indiv dot nluug dot nl, laurent at guerby dot net, fjahanian at apple dot com
Date: Wed, 24 Mar 2004 13:21:32 -0500
Subject: Re: GCC beaten by ICC in stupid trig test!

Re:

On Tue, Mar 23, 2004 at 10:32:13PM -0500, Robert Dewar wrote:
> For example, if -ffast-math is so sloppy as to consider
> that (a+b)+c can be replaced by a+(b+c), then all bets are off.

That's why -ffast-math doesn't do that; such a transformation would be
massively brain-damaged.

Well, -ffast-math (or more specifically, -funsafe-math-optimizations) is about to do this, at least in some cases on tree-ssa, see

http://gcc.gnu.org/ml/gcc-patches/2004-03/msg01891.html

If you think that this transformation shouldn't be done, then I guess now is the time to speak up.

Brad

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- Re: GCC beaten by ICC in stupid trig test!
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