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From: FX <fxcoudert@gmail.com>
To: Thomas Koenig <tkoenig@netcologne.de>
Cc: gcc-patches@gcc.gnu.org, fortran@gcc.gnu.org
Subject: Re: [PATCH] Make integer output faster in libgfortran
Date: Sun, 26 Dec 2021 12:14:57 +0100	[thread overview]
Message-ID: <91272BC5-B108-4DB0-929C-EE437703F10B@gmail.com> (raw)
In-Reply-To: <43c60a0b-06b5-162b-bd5f-a7177cd76172@netcologne.de>

Hi,

> I tested this on x86_64-pc-linux-gnu with
> make -k -j8 check-fortran RUNTESTFLAGS="--target_board=unix'{-m32,-m64}'"
> and didn't see any problems.

Thanks Thomas! Pushed.


> (We could also do something like that for a 32-bit system, but
> that is another kettle of fish).

We probably wouldn’t get a speed-up that big. Even on 32-bit targets (at least common ones), the 64-bit type and its operations (notably division) are implemented via CPU instructions, not library calls.

At this point, the output of integers is probably bound by the many layers of indirection of libgfortran's I/O system (which are necessary because of the rich I/O formatting allowed by the standard).

Best,
FX

  reply	other threads:[~2021-12-26 13:14 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-25 13:03 FX
2021-12-25 14:35 ` Thomas Koenig
2021-12-25 14:50   ` FX
2021-12-25 22:07     ` Thomas Koenig
2021-12-26 11:14       ` FX [this message]
2021-12-26 16:15         ` Thomas Koenig
2021-12-27 21:01           ` FX

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