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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>
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Subject: Re: FreeBSD 5.2 v/s FreeBSD 4.9 MFLOPS performance (gcc3.3.3 v/s
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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