[PATCH] Optimize SSE 4.1 x86_64 memcmp

[Florian Weimer]

On 02/04/2014 01:30 PM, Florian Weimer wrote:
> On 02/03/2014 10:30 PM, Carlos O'Donell wrote:
>
>>> Unaligned loads overlapping with data previously compared as equal.
>>> This data cannot affect the outcome of the final comparison.  (This
>>> trick was already used before, but it's not entirely obvious.)
>>>
>>> The SETNE/CMOVAE sequence for the branchless sign function.
>
> (It turns out that this part is not actually present anymore.)
>
>> No, that looks good from a commenting perspective.
>
> I have incorporated the comment updates.

And here's the patch.

-- 
Florian Weimer / Red Hat Product Security Team
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