From owner-freebsd-alpha@FreeBSD.ORG  Thu Aug  7 19:05:56 2003
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Date: Thu, 7 Aug 2003 22:05:54 -0400 (EDT)
From: Daniel Eischen <eischen@vigrid.com>
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To: "David O'Brien" <obrien@freebsd.org>
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cc: "Portante, Peter" <peter.portante@hp.com>
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Subject: Re: Atomic swap
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On Thu, 7 Aug 2003, David O'Brien wrote:

> On Thu, Aug 07, 2003 at 01:44:18PM -0400, Daniel Eischen wrote:
> > 		"beq %1, 2f\n\t"	/* if the store failed, spin */
> 
> It is worth explaining why this is "beq" since it wasn't obvious to all
> readers. :-)

Well, when you catch up on you're reading, you'll see the
forward branch is no longer there.  But FYI, it was
supposedly there because it was thought that Alpha's
always predicted a backwards branch, so the common
case of the store succeeding wasn't optimized.

-- 
Dan Eischen