Re: [Altivec Newbie] optimizing current code?

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#60

From: Ian Ollmann
Date: Thu, 18 Jan 2001 21:49

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On 18 Jan 2001, Dave Howell wrote:

> > > 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, you misunderstood. He didn't say it helps CodeWarrior to optimize,
> but that it helped HIM to optimize. If your code is written one
> instruction per line, it's easier from an editing standpoint to reorder
> operations later, than if you have to edit complex vector expressions.

I understood perfectly. Reordering the instructions line by line by hand
doesn't do much if Codewarrior is doing the scheduling for you. It will
rearrange them right back the way it wants them in my experience. I guess
he could turn scheduling off, but goodness that wouldn't help the rest of
the program much.

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: Thu, 18 Jan 2001 13:49:50 -0800
Organization: California Institute of Technology, Pasadena
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