From: Paul E Murphy <murphyp@linux.ibm.com>
To: Paul Zimmermann <Paul.Zimmermann@inria.fr>, libc-alpha@sourceware.org
Subject: Re: faster expf128
Date: Mon, 22 Jun 2020 08:59:08 -0500 [thread overview]
Message-ID: <a5cf1511-d1d1-39b2-ea28-fd84eb5c5361@linux.ibm.com> (raw)
In-Reply-To: <mwmu4v4b42.fsf@tomate.loria.fr>
On 6/22/20 6:02 AM, Paul Zimmermann wrote:
> I have written some expf128 for x86_64 that is more than 10 times faster than
> the current glibc/libquadmath code [1] (see slide 21 of [2]).
I would highly recommend running the benchmarks against ppc64le or s390x
before replacing the existing implementation. I think it would improve
the code to have more explicit separation between implementations
optimized for soft and hardfp if performance cannot be rectified. I
think much of the float128 support assumes the underlying machine does
not natively support binary128.
>
> Before making a proper patch for glibc, I'd like to make sure it fits the
> glibc requirements. In particular, the table size is 16kb. Is that ok?
> If too large, what table size would be ok?
I think that is acceptable. The current tables for expf128 probably
aren't much smaller, if I recall correctly.
next prev parent reply other threads:[~2020-06-22 13:59 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-22 11:02 Paul Zimmermann
2020-06-22 13:59 ` Paul E Murphy [this message]
2020-06-22 21:18 ` Joseph Myers
2020-06-24 6:22 ` Paul Zimmermann
2020-06-24 17:39 ` Joseph Myers
2020-06-26 10:09 ` Szabolcs Nagy
2020-06-29 22:39 ` Joseph Myers
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