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Date: Tue, 13 Jun 2006 13:10:54 -0700
From: Arjan van de Ven <arjan@linux.intel.com>
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To: Andreas Mohr <andi@rhlx01.fht-esslingen.de>
CC: Andrew Morton <akpm@osdl.org>, Andi Kleen <ak@suse.de>,
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Subject: Re: [PATCH -mm] i386 usercopy.c opcode reordering (pipelining)
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Andreas Mohr wrote:
> Hi all,
> 
> this one wrote to register %0 and immediately right-shifted it,
> so let's andl register %3 first for better parallelism (rrright?).

have you benchmarked this?
I would actually expect no difference since a reg-reg move is basically
a thing for the register rename engine which then... well it's supposed
to be near free like this.