From: Toon Moene <toon@moene.org>
To: gcc@gcc.gnu.org
Subject: Re: Complex numbers support: discussions summary
Date: Tue, 26 Sep 2023 20:40:20 +0200 [thread overview]
Message-ID: <87d8389c-3ff5-45ed-bc5e-19463564d703@moene.org> (raw)
In-Reply-To: <CAFiYyc1WeP-0SCQgNv3rO0+cPSrW7ne9M8iJqd_=wEqO+0-Qdw@mail.gmail.com>
On 9/26/23 09:30, Richard Biener via Gcc wrote:
> On Mon, Sep 25, 2023 at 5:17 PM Sylvain Noiry via Gcc <gcc@gcc.gnu.org> wrote:
>> As I said at the end of the presentation, we have written a paper which
>> explains
>> our implementation in details. You can find it on the wiki page of the
>> Cauldron
>> (https://gcc.gnu.org/wiki/cauldron2023talks?action=AttachFile&do=view&target=Exposing+Complex+Numbers+to+Target+Back-ends+%28paper%29.pdf).
>
> Thanks for the detailed presentation at the Cauldron.
>
> My personal summary is that I'm less convinced delaying lowering is
> the way to go.
Thanks Sylvain for the quick summary of the discussion - it helps a
great deal now that the discussion is still fresh in our memory.
Some thought I came up with (of course, only after the end of the
conference):
In what way is the handling of the complex type different from that of
the 128 bit real (i.e., float) type ?
Both are not implemented on most architectures; on most they require two
registers (or possibly two memory location that do not necessarily have
to be adjacent) to be implemented.
Yet both are supported by the middle end - consider the clear
equivalence of the handling of variables a and b when looking at the
result of -fdump-tree-ssa (on x86_64) for:
cat 128.f90
parameter (iq=kind(1q0))
real(kind=iq) :: a, b
read*, a, b
print*, a / b
end
and:
cat complex.f90
complex a,b
read*,a,b
print*,a/b
end
Hope this helps for a continuing fruitful discussion.
Kind regards,
--
Toon Moene - e-mail: toon@moene.org - phone: +31 346 214290
Saturnushof 14, 3738 XG Maartensdijk, The Netherlands
next prev parent reply other threads:[~2023-09-26 18:40 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-25 15:15 Sylvain Noiry
2023-09-26 7:30 ` Richard Biener
2023-09-26 8:29 ` Tamar Christina
2023-09-26 10:19 ` Paul Iannetta
2023-09-26 8:53 ` Paul Iannetta
2023-09-26 9:28 ` Tamar Christina
2023-09-26 9:40 ` Paul Iannetta
2023-09-26 18:40 ` Toon Moene [this message]
2023-10-05 14:45 ` Toon Moene
2023-09-26 15:46 ` Joseph Myers
-- strict thread matches above, loose matches on Subject: below --
2023-10-16 9:14 Sylvain Noiry
2023-10-17 20:37 ` Toon Moene
2023-10-18 7:24 ` Sylvain Noiry
2023-10-09 13:29 Sylvain Noiry
2023-09-25 14:56 Sylvain Noiry
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