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Re: [PATCH v3] ARM: Improve armv7 memcpy performance.


On Mon, 9 Sep 2013, Will Newton wrote:

> Only enter the aligned copy loop with buffers that can be 8-byte
> aligned. This improves performance slightly on Cortex-A9 and
> Cortex-A15 cores for large copies with buffers that are 4-byte
> aligned but not 8-byte aligned.

Did you conclude that the comment about needing unaligned word access for 
ldrd/strd is still accurate after this patch (and if so, for which uses)?

There was a long discussion on benchmarking starting from this patch.  
Could you summarise the conclusions of that discussion as they relate to 
the appropriate benchmarks to apply to this patch, and give pointers to 
your before-and-after performance results?

-- 
Joseph S. Myers
joseph@codesourcery.com


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