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Re: [Patch] Adjust diag-scans in vect-tests to fix fails on AVX/AVX2
> Why? SSSE3 *really can* do arbitrary permutation. If you say that
> isn't enough, then there's something wrong in the back end, and all
> you're doing is papering over a bug.
Yes, sure, SSSE3 is enough for that. I checked for AVX in vect_perm
just because there is no check for SSSE3 and no tests currently
require exactly SSSE3 (without AVX) - that's not absolutely correct
and I suggest it as a temporary solution - we can weaken this check
when a real case will be met (in which SSSE3 is needed without AVX).
On 16 December 2011 20:42, Richard Henderson <rth@redhat.com> wrote:
> On 12/15/2011 11:21 PM, Michael Zolotukhin wrote:
>> E.g., in vect-114.c we need permutation only for reversing vector
>> elements, even ssse3 isn't required for it ...
>
> Sure.
>
>> while in slp-perm-9 such permutation isn't enough.
>
> Why? ?SSSE3 *really can* do arbitrary permutation. ?If you say that
> isn't enough, then there's something wrong in the back end, and all
> you're doing is papering over a bug.
>
> Changing vect_perm to require AVX is wrong.
>
>
> r~
--
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Best regards,
Michael V. Zolotukhin,
Software Engineer
Intel Corporation.