Re: [PATCH -mm] i386 usercopy.c opcode reordering (pipelining)

From: Arjan van de Ven
Date: Tue Jun 13 2006 - 16:10:48 EST


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.
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