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Date:      Mon, 16 Feb 2004 20:16:58 +0000
From:      Bruce M Simpson <bms@spc.org>
To:        Dag-Erling =?iso-8859-1?Q?Sm=F8rgrav?= <des@des.no>
Cc:        Kris Kennaway <kris@obsecurity.org>
Subject:   Re: FreeBSD 5.2 v/s FreeBSD 4.9 MFLOPS performance (gcc3.3.3 v/s gcc2.9.5)
Message-ID:  <20040216201658.GE3791@saboteur.dek.spc.org>
In-Reply-To: <xzpn07i28u3.fsf@dwp.des.no>
References:  <BAY12-F37zmBUw7MurD00010899@hotmail.com> <20040214082420.GB77411@nevermind.kiev.ua> <xzpvfm8yssm.fsf@dwp.des.no> <200402160352.16477.wes@softweyr.com> <20040216035412.GA70593@xor.obsecurity.org> <xzpn07i28u3.fsf@dwp.des.no>

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On Mon, Feb 16, 2004 at 07:11:16PM +0100, Dag-Erling Smørgrav wrote:
> It can't possibly hurt.  If the stack is already aligned on a "better"
> boundary (64 or 128 bytes), it is also aligned on a 32-byte boundary
> since 64 and 128 are multiples of 32, and the patch is a no-op.  If
> only a 16-byte alignment is required, a 32-byte alignment wastes a
> small amount of memory but does not hurt performance.  I believe that
> less-than-16 (and possibly even less-than-32) alignment is pessimal on
> all platforms we support.

I'm not happy with the patch as-is and would be happier if a cleaner
MI-way of expressing this were found.

BMS



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