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From: Florian Weimer via Libc-alpha <libc-alpha@sourceware.org>
To: Paul Zimmermann <Paul.Zimmermann@inria.fr>
Cc: libc-alpha@sourceware.org
Subject: Re: fix inaccuracy of j0f for x >= 2^127 when sin(x)+cos(x) is tiny (v3)
Date: Thu, 30 Jul 2020 10:53:24 +0200	[thread overview]
Message-ID: <87lfj1jse3.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <mwy2n1tqof.fsf@tomate.loria.fr> (Paul Zimmermann's message of "Thu, 30 Jul 2020 09:20:16 +0200")

* Paul Zimmermann:

>        Dear Adhemerval,
>
> thank you again for your useful comments.
>
>> Does it require any ULP adjustment (at least on the architecture you
>> tested it)?
>
> I reset to 0 the j0/float values in sysdeps/x86_64/fpu/libm-test-ulps,
> then ran "make regen-ulps", and got:
>
> $ diff ../sysdeps/x86_64/fpu/libm-test-ulps /localdisk/zimmerma/glibc/build/math/NewUlps
> 1315c1315
> < float: 0
> ---
>> float: 8
> 1321c1321
> < float: 0
> ---
>> float: 4
> 1327c1327
> < float: 0
> ---
>> float: 5
> 1333c1333
> < float: 0
> ---
>> float: 5
>
> which were the original values except for j0_towardzero (it was 6).
> However the same applies to "master", so this is independent from my change.
> Anyway, I decreased the value from 6 to 5.

I suggest to leave it at 6, other CPU variants may still need the 6
there.

Thanks,
Florian


  reply	other threads:[~2020-07-30  8:53 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-27 17:15 fix inaccuracy of j0f for x >= 2^127 when sin(x)+cos(x) is tiny Paul Zimmermann
2020-07-27 21:35 ` Joseph Myers
2020-07-28  8:23   ` Paul Zimmermann
2020-07-28  9:19     ` Andreas Schwab
2020-07-28 10:50       ` Paul Zimmermann
2020-07-28 18:09         ` Adhemerval Zanella via Libc-alpha
2020-07-29  7:03           ` fix inaccuracy of j0f for x >= 2^127 when sin(x)+cos(x) is tiny (v2) Paul Zimmermann
2020-07-29 20:25             ` Adhemerval Zanella via Libc-alpha
2020-07-30  7:20               ` fix inaccuracy of j0f for x >= 2^127 when sin(x)+cos(x) is tiny (v3) Paul Zimmermann
2020-07-30  8:53                 ` Florian Weimer via Libc-alpha [this message]
2020-08-03 13:19                   ` fix inaccuracy of j0f for x >= 2^127 when sin(x)+cos(x) is tiny (v4) Paul Zimmermann

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