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Re: [PATCH] Faster strchr implementation.

On Fri, Aug 09, 2013 at 06:05:43PM +0400, Liubov Dmitrieva wrote:
Yes, thanks. I updated with them pages:

As you can see graphs strcmp is 10% faster on haswell, atom and

As avx2 implementation goes on haswell it is around 20% faster on large
inputs, but problem there is that most of time inputs are small. Using
avx is around 3% slower than strcmp_new on gcc test. One possible cause is
bigger latency of avx2, it may be worth to add avx2 ifunc.

As strchr is concerned a no_bsf version is still faster on atom and
silvermont. My implementation win for larger sizes but I pays heavy penalty 
for switching to 64 byte loop while strchr_no_bsf loop is cheap.

A strrchr a new implementation is faster than current ones both
practically and asymptotically on haswell,atom and silvermont.

As haswell I fixed strchr and strrchr benchmarks to call correct avx2
implementation. New version is here:

It was bug in implementation, now fixed.
They are tested automatically.


endothermal recalibration

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