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Re: [PATCH v3] aarch64: Optimized implementation of memcmp


Hi Xuelei,

> The loop body is expanded from a 16-byte comparison to a 64-byte
> comparison, and the usage of ldp is replaced by the Post-index
> mode to the Base plus offset mode. Hence, compare can faster 18%
> around > 128 bytes in all.

>> So why not use 2xCSEL rather than a branch across the moves?
>> That's going to be faster since the branch will be hard to predict.
>
> Great! This can reduce one branch prediction, and I have modified as suggested.
>
> Other problems like unused label and format is also corrected.

Thanks, this version looks good. OK to commit.

Wilco



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