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Re: [PATCH] Rename __memcmp_sse4_2 to __memcmp_sse4_1.


On Tue, Jul 9, 2013 at 9:37 PM, Andreas Jaeger <aj@suse.com> wrote:
> On 07/10/2013 03:17 AM, Matt Turner wrote:
>> It uses SSE 4.1 instructions (ptest) but no SSE 4.2 instructions.
>
> There are two parts to this: It should only run on cpus with those
> instructions but we also need to ensure that it gives a better
> performance on such cpus. HJ, Matt, please do run performance tests on a
> variety of affected cpus to show that this change really helps in all cases,
>
> Andreas

Only Penryn has SSE4.1 without SSE4.2.  Liubov, can
you compare performance of memcmp-sse4.S vs
memcmp-ssse3.S on Penryn?

Thanks.


--
H.J.


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