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Date:      Wed, 26 Feb 2003 21:55:48 +0000
From:      Nuno Teixeira <nunotex@aeiou.pt>
To:        current@FreeBSD.ORG
Subject:   Re: -O2 considered harmful
Message-ID:  <20030226215547.GA5510@gw.tex.bogus>
In-Reply-To: <20030226200635.GA1368@torment.storming.org>
References:  <xzpy943xnhx.fsf@flood.ping.uio.no> <20030226113815.W5357@znfgre.tberna.bet> <20030226200635.GA1368@torment.storming.org>

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Hi,

Just a little question:

Does -march=k6-2 implies -m3dnow? Or -march=pentiumpro implies -mmmx?

I always thought that when I use -march it will enable other
porcessor specific optimizations like mmx and 3dnow (if available).


Thanks,

		Nuno Teixeira

On Wed, Feb 26, 2003 at 05:06:35PM -0300, Fred Souza wrote:
> > I was recently a participant in a thread in another forum where all sorts
> > of people, including a well respected gcc developer, said categorically
> > that the latest (stock) gcc produces correct code with -O2 in all cases on
> > ia32. If it doesn't, the gcc folks would like a bug report.
> 
>   I use -O3 -mmmx -m3dnow -march=k6-2 on nearly everything (things that
>   break with that many optimization, such as XFree86-4-libraries, I
>   "downgrade" to the highest optimization possible - usually -O2), and
>   I'm not noticing any bad impacts because of it.
> 
>   And by "nearly everything" I even meant the kernel (yes, I can respect
>   if anyone screams "NUTZ!@!" ;-)
> 
> 
>   Fred
> 
> 
> -- 
> Insulting a person's appearance:
> 
> 	That's what they mean by dark and handsome. When it's dark, you're
> 	handsome...



-- 

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