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Subject: Re: GNAT Optimization of Constant Expressions
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From: Ray Blaak <rAYblaaK@STRIPCAPStelus.net>
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Date: Fri, 18 May 2007 16:25:14 GMT
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Date: 2007-05-18T16:25:14+00:00
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"Randy Brukardt" <randy@rrsoftware.com> writes:
> One example is:
>      Y := (X - 0.5) - 0.5;
> 
> You might think that replacing this with
>     Y := X - 1.0;
> would be a good idea, but actually it reduces the accuracy of the result

I don't understand this. Both 0.5 and 1.0 have "exact" binary representations
right? 

Can you give a value of X where this would hold?

-- 
Cheers,                                        The Rhythm is around me,
                                               The Rhythm has control.
Ray Blaak                                      The Rhythm is inside me,
rAYblaaK@STRIPCAPStelus.net                    The Rhythm has my soul.