Re: [Altivec Newbie] optimizing current code?

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From: Ian Ollmann
Date: Thu, 18 Jan 2001 01:36

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On Wed, 17 Jan 2001, Darrin Cardani wrote:

> It's not that bad, really. You can even do crazy things like:
>
> v1 = vec_add (vec_sub(v1,v2), vec_add (v3,v4));
>
> That's equivalent to
>
> v1 = (v1 - v2) + (v3 + v4);
>
> Personally, I try to keep things to one AltiVec instruction per line.
> It helps me optimize later, but there's no reason you have to do it
> that way.

CodeWarrior does a reasonable job at scheduling if you write in C, so I am
curious how keeping things one per line helps you optimize.

Ian

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   Ian Ollmann, Ph.D.       iano@cco.caltech.edu
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From: Ian Ollmann <iano@cco.caltech.edu>
Newsgroups: comp.sys.mac.programmer.help,comp.sys.mac.programmer.codewarrior,codewarrior.mac
Subject: Re: [Altivec Newbie] optimizing current code?
Date: Wed, 17 Jan 2001 17:36:26 -0800
Organization: California Institute of Technology, Pasadena
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