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Date: Tue, 08 Jul 2014 11:14:00 -0000
From: Kirill Yukhin <kirill.yukhin@gmail.com>
To: Marc Glisse <marc.glisse@inria.fr>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>, Uros Bizjak <ubizjak@gmail.com>
Subject: Re: [i386] Replace builtins with vector extensions
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Hello Marc.
On 04 Jul 21:11, Marc Glisse wrote:
> On Thu, 3 Jul 2014, Kirill Yukhin wrote:
> like combining 2 shuffles unless the result is the identity. And
> expanding shuffles that can be done in a single instruction works
> well.
> 
> But I am happy not doing them yet. To be very specific, could you
> list which intrinsics you would like to remove from the posted
> patch?
I am not a x86 maintainer, however while such a replacements produce
correct semantics and probably enable optimizations, I support your patch.

Probably you could try such your approach on AVX2, AVX-512 whose intrinsics
are well covered by tests?

> >On the over hand, updated in such a way intrinsic
> >may actually generate different instruction then intended (e.g. FMA case).
> 
> It is the same with scalars, we have -ffp-contract for that.
Agreed.

--
Thanks, K