[Pixman] [PATCH 0/4] More VMX enhancements

[Oded Gabbay]

On Mon, Sep 7, 2015 at 2:04 PM, Pekka Paalanen <ppaalanen at gmail.com> wrote:
> On Sun,  6 Sep 2015 18:27:07 +0300
> Oded Gabbay <oded.gabbay at gmail.com> wrote:
>
>> This patch-set contains optimizations for two existing VMX fast-paths and a new
>> VMX fast-path function.
>>
>> The optimization ideas came from Siarhei's recent implementation of over_n_8888
>> VMX fast path (see http://lists.freedesktop.org/archives/pixman/2015-September/003951.html).
>>
>> The new function I added is actually one that I already implemented a couple
>> of months ago, but it produced conflicting results regarding the performance.
>> However, I now optimized it and it now shows considerable performance
>> improvement over the non-vmx path.
>>
>> The last patch removes many helper functions that caused the less than stellar
>> performance the current fast-paths provide. I removed them as I don't want
>> anyone to try and use them, because there are much better alternatives, as
>> I've demonstrated with this patch-set.
>>
>> Thanks,
>>
>>       Oded
>>
>> Oded Gabbay (4):
>>   vmx: optimize scaled_nearest_scanline_vmx_8888_8888_OVER
>>   vmx: optimize vmx_composite_over_n_8888_8888_ca
>>   vmx: implement fast path vmx_composite_over_n_8_8888
>>   vmx: Remove unused expensive functions
>>
>>  pixman/pixman-vmx.c | 439 ++++++++++++++++++----------------------------------
>>  1 file changed, 150 insertions(+), 289 deletions(-)
>>
>
> Hi Oded,
>
> nice diffstat. :-)
>
> This series is:
> Acked-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
>
> I did notice a few minor issues. Patch 1 has a dereference before
> NULL-check, and you sometimes forget the space before an opening
> parenthesis.
>
> I suppose there is no danger of regressing operations you didn't
> touch? ;-)
>
>
> Thanks,
> pq

HI Pekka,
I run cario benchmark (trimmed) and there was *no* regression.
I don't think optimizing some fast-paths affects other, non-related,
fast-paths. And, of course, I don't think it has *any* impact on non
POWER systems.
However, if someone thinks of a specific other function I need to
check for regression, I'm open for suggestions :)

         Oded