Atomic swap
Daniel Eischen
eischen at vigrid.com
Thu Aug 7 19:05:56 PDT 2003
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
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