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Re: FP negation optimization

From: Robert Dewar <dewar at gnat dot com>
To: Robert Dewar <dewar at gnat dot com>
Cc: Andrew Pinski <pinskia at physics dot uc dot edu>,Chris Lattner <sabre at nondot dot org>, gcc at gcc dot gnu dot org,Richard Henderson <rth at redhat dot com>
Date: Sun, 01 Feb 2004 21:11:49 -0500
Subject: Re: FP negation optimization
References: <Pine.LNX.4.44.0402011705550.31630-100000@nondot.org> <12EEF394-550B-11D8-8AEA-000393A6D2F2@physics.uc.edu> <401D9F31.40609@gnat.com>

I agree that this optimization is "wrong" if you expect IEEE
semantics to be observed. Interestingly, Ada requires that this
be done right, to be checked!


I checked, and Ada gets it right at -O2, not sure what the
story is, to be investigated.

References:
- Re: FP negation optimization
  - From: Chris Lattner
- Re: FP negation optimization
  - From: Andrew Pinski
- Re: FP negation optimization
  - From: Robert Dewar

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