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Re: [PATCH] Make strcmp optimized for SSE2 with unaligned load/store as default


On Tue, Aug 25, 2015 at 11:59 AM, Roland McGrath <roland@hack.frob.com> wrote:
> Making ld.so use the same code as libc should be a separate change from
> anything changing anything about the strcmp implementation itself.  The
> latter is billed as a performance improvement and so needs a report about
> the benchmarks or other performance analysis that justify it.

Here is a patch to make strcmp_sse2_unaligned the default.  The actual
change isn't very big:

 rename sysdeps/x86_64/{strcmp.S => strcmp-sse2-aligned.S} (99%)
 rename sysdeps/x86_64/{multiarch/strcmp-sse2-unaligned.S => strcmp.S} (98%)

Although I don't have any benchmarks nor performance analysis, given
that unaligned load/store is fast on recent Intel and AMD processors,
it should be the default.

OK for master?

-- 
H.J.

Attachment: 0001-Make-strcmp-with-unaligned-load-store-the-default.patch.xz
Description: application/xz


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