[PATCH RFC] Imporve 64bit memset performance for Haswell CPU with AVX2 instruction

[H.J. Lu]

On Tue, Jun 10, 2014 at 6:52 AM, Ling Ma <ling.ma.program@gmail.com> wrote:
> In this patch as gziped attachment, we take advantage of HSW memory
> bandwidth, manage to reduce miss branch prediction by avoiding using
> branch instructions and
> force destination to be aligned with avx & avx2 instruction.
>
> The CPU2006 403.gcc benchmark indicates this patch improves performance
> from 26% to 59%.
>
> This version accept Ondra's comments and avoid branch instruction to
> cross 16byte-aligned code.

Any feedback?  I'd like to check it in before 2.20 code freeze.

Thanks.

-- 
H.J.