From owner-freebsd-hackers  Thu Jan 15 10:10:09 1998
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Date: Thu, 15 Jan 1998 12:34:54 -0500 (EST)
From: John D Duncan <jddst19+@pitt.edu>
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To: Archie Cobbs <archie@whistle.com>
cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: what does MMX mean?
In-Reply-To: <199801142355.PAA05051@bubba.whistle.com>
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The MMX instructions, as far as I can gather, are a new set of
instructions to provide parallel-style computation on packed registers
of 64-bit words. These instructions are intended to speed up repetative
computation such as a binary xor of a constant against four 16-bit
words by performing the computation simultaneously on all four rather
than looping through the computations.

The normal integer and floating-point datapaths are, i believe,
unaffected.

-John


       ==============

jddst19+@pitt.edu   John Duncan
		    Freshman, University of Pittsburgh

"I'm not a doctor, but I ate one at the UPMC..."


On Wed, 14 Jan 1998, Archie Cobbs wrote:

> 
> What, exactly, does MMX mean?
> 
> Does it mean the processor has NEW instructions for DSP type operations?
> Does it speed up EXISTING instructions? Integer or floating point (or both)?
> 
> Thanks,
> -Archie
> 
> ___________________________________________________________________________
> Archie Cobbs   *   Whistle Communications, Inc.  *   http://www.whistle.com
>