From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 122730 invoked by alias); 20 Mar 2017 14:54:43 -0000 Mailing-List: contact newlib-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: newlib-owner@sourceware.org Received: (qmail 122719 invoked by uid 89); 20 Mar 2017 14:54:42 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: Yes, score=6.3 required=5.0 tests=AWL,BAYES_50,FOREIGN_BODY,RCVD_IN_DNSWL_NONE,SPF_PASS,T_FILL_THIS_FORM_SHORT autolearn=no version=3.3.2 spammy=diese, brains, Nachricht, nachricht X-HELO: dedi548.your-server.de Received: from dedi548.your-server.de (HELO dedi548.your-server.de) (85.10.215.148) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 20 Mar 2017 14:54:40 +0000 Received: from [88.198.220.130] (helo=sslproxy01.your-server.de) by dedi548.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.85_2) (envelope-from ) id 1cpyhj-0005Ig-6A; Mon, 20 Mar 2017 15:54:39 +0100 Received: from [82.135.62.35] (helo=mail.embedded-brains.de) by sslproxy01.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.84_2) (envelope-from ) id 1cpyhi-0005H3-Ts; Mon, 20 Mar 2017 15:54:39 +0100 Received: from localhost (localhost.localhost [127.0.0.1]) by mail.embedded-brains.de (Postfix) with ESMTP id 5F6842A1663; Mon, 20 Mar 2017 15:55:03 +0100 (CET) Received: from mail.embedded-brains.de ([127.0.0.1]) by localhost (zimbra.eb.localhost [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id YiJn4LL2pICW; Mon, 20 Mar 2017 15:55:01 +0100 (CET) Received: from localhost (localhost.localhost [127.0.0.1]) by mail.embedded-brains.de (Postfix) with ESMTP id 0A7412A1664; Mon, 20 Mar 2017 15:55:01 +0100 (CET) Received: from mail.embedded-brains.de ([127.0.0.1]) by localhost (zimbra.eb.localhost [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id iE1WffIHfEhb; Mon, 20 Mar 2017 15:55:00 +0100 (CET) Received: from [192.168.96.129] (unknown [192.168.96.129]) by mail.embedded-brains.de (Postfix) with ESMTPSA id E7AE42A1663; Mon, 20 Mar 2017 15:55:00 +0100 (CET) Subject: Re: libm support for ARMv7 and VSQRT? To: "Richard Earnshaw (lists)" , "newlib@sourceware.org" References: <58CF7C40.3060609@embedded-brains.de> <29ebecaa-287d-57e9-cffe-d1b5a05a6a7b@arm.com> From: Sebastian Huber Message-ID: <58CFED2B.7040809@embedded-brains.de> Date: Mon, 20 Mar 2017 14:54:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <29ebecaa-287d-57e9-cffe-d1b5a05a6a7b@arm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: quoted-printable X-IsSubscribed: yes X-SW-Source: 2017/txt/msg00197.txt.bz2 On 20/03/17 14:31, Richard Earnshaw (lists) wrote: > On 20/03/17 06:52, Sebastian Huber wrote: >> Hello, >> >> there is some ARM-specific libm support for ARMv8: >> >> https://sourceware.org/git/gitweb.cgi?p=3Dnewlib-cygwin.git;a=3Dtree;f= =3Dnewlib/libm/machine/arm;h=3D5457f11619b2d67e8f56f352afb404c06a12c2bb;hb= =3DHEAD >> >> >> The VFPv2+ supports a VSQRT instruction. Would it make sense to use it >> for the sqrt() implementation, similar to >> >> https://sourceware.org/git/gitweb.cgi?p=3Dnewlib-cygwin.git;a=3Dblob;f= =3Dnewlib/libm/machine/aarch64/e_sqrt.c;h=3De4b7554ac1811bf04f726da198b913c= 0c30595ca;hb=3DHEAD >> >> https://sourceware.org/git/gitweb.cgi?p=3Dnewlib-cygwin.git;a=3Dblob;f= =3Dnewlib/libm/machine/aarch64/ef_sqrt.c;h=3D19fec952517769ad3851efef3b11dc= 6c02fb7582;hb=3DHEAD >> >> >> ? >> > I'm sure a patch would be welcome :-) The ARMv7-AR reference manual is quite verbose if it comes to the=20 floating-point square root implementation of VSQRT. Is it IEEE 754=20 compatible? --=20 Sebastian Huber, embedded brains GmbH Address : Dornierstr. 4, D-82178 Puchheim, Germany Phone : +49 89 189 47 41-16 Fax : +49 89 189 47 41-09 E-Mail : sebastian.huber@embedded-brains.de PGP : Public key available on request. Diese Nachricht ist keine gesch=E4ftliche Mitteilung im Sinne des EHUG.