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Date: Mon, 05 Sep 2022 16:39:02 +0200
Message-Id: <mwzgfdansp.fsf@tomate.loria.fr>
From: Paul Zimmermann <Paul.Zimmermann@inria.fr>
To: Szabolcs Nagy <nsz@port70.net>
Cc: dalias@libc.org, musl@lists.openwall.com
In-Reply-To: <20220905130859.GO1320090@port70.net> (message from Szabolcs Nagy
	on Mon, 5 Sep 2022 15:08:59 +0200)
References: <mwv8q6ccj9.fsf@tomate.loria.fr>
 <20220902121755.GS7074@brightrain.aerifal.cx>
 <mw5yi2chn3.fsf@tomate.loria.fr> <20220905130859.GO1320090@port70.net>
Subject: Re: [musl] Re: integration of CORE-MATH routines into Musl?

       Dear Szabolcs,

> when i worked on exp and log i noticed that for single prec it is
> easy to do correct rounding with only minor overhead, but it required
> either a bit bigger lookup table or a bit bigger polynomial vs going
> for < 1 ulp error only.

please have a look at https://gitlab.inria.fr/core-math/core-math/-/blob/master/src/binary32/exp/expf.c: no big lookup table, degree 5 only.

Paul