From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: Janus Weil <janus@gcc.gnu.org>
Cc: gfortran <fortran@gcc.gnu.org>, gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: [Patch, Fortran] PR 82143: add a -fdefault-real-16 flag
Date: Mon, 18 Sep 2017 14:08:00 -0000 [thread overview]
Message-ID: <20170918140823.GA83251@troutmask.apl.washington.edu> (raw)
In-Reply-To: <CAKwh3qgQKeAKzO0qSf84gQiZ5PgdLZtMBDdA7NoB-z1qAKvYSA@mail.gmail.com>
On Mon, Sep 18, 2017 at 09:02:22AM +0200, Janus Weil wrote:
> Hi Steve,
>
> >> attached is a (technically) simple patch that implements the compiler
> >> flag "-fdefault-real-16" for gfortran.
> >
> > What about -fdefault-real-10? If you're going to add bloat to the
> > compiler, then you might as well to it right.
>
> well, yeah. If my only aim was to add bloat to the compiler out of
> plain boredom and nastiness, then I might as well add
> -fdefault-real-37. But I don't think that would be very useful.
Why? One gets 11-bits of additional precision (on most platforms)
and a significant increase in the exponent range (+- ~1024 to
+- ~16384). REAL(10) maps to hardware floating point, which is
faster than software quad precision.
--
Steve
20170425 https://www.youtube.com/watch?v=VWUpyCsUKR4
20161221 https://www.youtube.com/watch?v=IbCHE-hONow
next prev parent reply other threads:[~2017-09-18 14:08 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-17 20:42 Janus Weil
2017-09-18 4:51 ` Steve Kargl
2017-09-18 7:02 ` Janus Weil
2017-09-18 14:08 ` Steve Kargl [this message]
2017-09-18 17:57 ` Janus Weil
2017-09-21 7:10 ` Janus Weil
2017-09-21 20:38 ` Steve Kargl
2017-09-22 5:03 ` Janus Weil
2017-09-22 7:12 ` Janne Blomqvist
2017-09-22 9:44 ` Janus Weil
2017-09-22 19:32 ` Janus Weil
2017-09-23 13:19 ` Janus Weil
2017-09-22 14:06 ` Steve Kargl
2017-09-18 9:31 Dominique d'Humières
2017-09-18 18:13 ` Janus Weil
2017-09-22 10:06 ` Dominique d'Humières
2017-09-22 11:21 ` Janus Weil
2017-09-22 14:37 ` Steve Kargl
2017-09-22 22:46 ` Dominique d'Humières
2017-09-22 23:47 ` Steve Kargl
2017-12-03 17:36 ` Gerald Pfeifer
2017-09-18 9:38 Dominique d'Humières
2017-09-25 15:07 David Edelsohn
2017-09-25 21:14 ` Janus Weil
2017-09-25 21:23 ` Steve Kargl
2017-09-26 8:44 ` Janus Weil
2017-09-26 9:03 ` Janus Weil
2017-09-26 9:12 ` Rainer Orth
2017-09-26 9:47 ` Janus Weil
2017-09-26 14:54 ` David Edelsohn
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