Re: Question on optimizing "abs()"

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#252

From: Paul Eggert
Date: Sat, 15 Aug 1992 00:09

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schmid@deneb.cbmvax.cbm.commodore.com (Bob Schmid) writes:

>I would like to write code for gcc 2.2 that will take the absolute
>value of a double in the fastest possible way.

Why not just use the `fabs' function?  On my machine (GCC 2.2.2 -O,
Sparc, SunOS 4.1.2) `fabs' takes just one machine instruction, e.g.
`fabss %f0,%f0'.

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Path: arc1-ca.pugleaf.net!sparky!uunet!elroy.jpl.nasa.gov!ucla-cs!twinsun!eggert
From: eggert@twinsun.com (Paul Eggert)
Subject: Re: Question on optimizing "abs()"
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Date: Sat, 15 Aug 1992 00:09:40 GMT
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