Re: [PATCH 10/27] S390: Optimize stpcpy and wcpcpy.

[Stefan Liebler <stli at linux dot vnet dot ibm dot com>]

On 07/03/2015 10:11 PM, OndÅej BÃlka wrote:
> Here you could improve performance by using different ends so you could
> increase src and dest by 64 at end. That will allow simpler addressing
> which may help with ooo execution. If space is concern then following
> pattern looks promising:
>
> while (1)
> {
> if (has_zero(src))
>    goto add0;
> if (has_zero(src+16))
>    goto add16;
> if (has_zero(src+32))
>    goto add32;
> if (has_zero(src+48))
>    goto add48;
>    x+=64;
>    n+=64;
> }
>
> add48:
> src+=16;
> dest+=16;
>
> add32:
> src+=16;
> dest+=16;
>
> add16:
> src+=16;
> dest+=16;
>
> add0:
Ok. Thanks. I've changed it for stp/wcpcpy with this patch
and for str/wcscpy, strcat/wcscat and the variants with given maxlen 
with separate ones.

The changelog remains the same.
Bye Stefan

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