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Date: Tue, 10 Nov 2015 13:02:00 -0000
Message-ID: <CAMbmDYa7pnw53Rr4QWctKOz=MAC-6kiBmDS7W29LzN35QWq9wg@mail.gmail.com>
Subject: Re: [RFC] Combine vectorized loops with its scalar remainder.
From: Ilya Enkovich <enkovich.gnu@gmail.com>
To: Richard Biener <richard.guenther@gmail.com>
Cc: Yuri Rumyantsev <ysrumyan@gmail.com>, gcc-patches <gcc-patches@gcc.gnu.org>, 	Jeff Law <law@redhat.com>, Igor Zamyatin <izamyatin@gmail.com>
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2015-11-10 15:30 GMT+03:00 Richard Biener <richard.guenther@gmail.com>:
> On Tue, Nov 3, 2015 at 1:08 PM, Yuri Rumyantsev <ysrumyan@gmail.com> wrote:
>> Richard,
>>
>> It looks like misunderstanding - we assume that for GCCv6 the simple
>> scheme of remainder will be used through introducing new IV :
>> https://gcc.gnu.org/ml/gcc-patches/2015-09/msg01435.html
>>
>> Is it true or we missed something?
>
> <quote>
>> > Do you have an idea how "masking" is better be organized to be usable
>> > for both 4b and 4c?
>>
>> Do 2a ...
> Okay.
> </quote>

2a was 'transform already vectorized loop as a separate
post-processing'. Isn't it what this prototype patch implements?
Current version only masks loop body which is in practice applicable
for AVX-512 only in the most cases.  With AVX-512 it's easier to see
how profitable masking might be and it is a main target for the first
masking version.  Extending it to prologues/epilogues and thus making
it more profitable for other targets is the next step and is out of
the scope of this patch.

Thanks,
Ilya

>
> Richard.
>