[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20220310170531.GV7074@brightrain.aerifal.cx>
Date: Thu, 10 Mar 2022 12:05:32 -0500
From: Rich Felker <dalias@...c.org>
To: Norbert Lange <nolange79@...il.com>
Cc: musl@...ts.openwall.com
Subject: Re: asinf pulls in sqrt (double version)
On Thu, Mar 10, 2022 at 04:44:37PM +0100, Norbert Lange wrote:
> Hello,
>
> pulled some of the math routines for a float-only project,
> what I found is that asinf pulls in sqrt, and I cant tell whether this
> is necessary because of precision.
>
> The line is in src/math/asinf.c:
> s = sqrt(z);
It looks like it's intentional -- s has type double and is used in an
expression where the additional precision would make a difference:
x = pio2 - 2*(s+s*R(z));
I suspect it would be more work (and slower) to get suitable precision
without the double intermediate here, but I have not done the analysis
myself.
Rich
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
