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Mail Archives: pgcc/1999/10/18/16:37:45

Date: Mon, 18 Oct 1999 21:52:03 +0200
From: Marc Lehmann <pcg AT opengroup DOT org>
To: pgcc AT delorie DOT com
Subject: Re: using cmov* not that great
Message-ID: <19991018215203.B612@cerebro.laendle>
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In-Reply-To: <380A4183.B3794352@lycosmail.com>; from Adam Schrotenboer on Sun, Oct 17, 1999 at 05:37:08PM -0400
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On Sun, Oct 17, 1999 at 05:37:08PM -0400, Adam Schrotenboer <ajschrotenboer AT lycosmail DOT com> wrote:
> I can not thing of any (intel x86 at least) cpu that can use such.

Sure it can. One can reorder code that it suits static prediction.

> Itanium (stupid name, Merced was better) however I do believe will be

even better, it can just execute the if branch speculatively and then use
the equivalent of cmov/cadd. calculating two much in many cases hurts less
than a single jump.

-- 
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      ---==---(_)__  __ ____  __       Marc Lehmann      +--
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    The choice of a GNU generation                       |
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