From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by sourceware.org (Postfix) with ESMTPS id 92CBB3858D32 for ; Thu, 13 Apr 2023 12:21:11 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 92CBB3858D32 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=inria.fr Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=inria.fr DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=inria.fr; s=dc; h=date:message-id:from:to:cc:in-reply-to:subject: references; bh=3V90YZj4/r7IZjbTmx/01CA1NAxkvBeoqQ9v593+kro=; b=vIUbG8Id42PyE1Xm1AjaN1iSyUJh7gBjFyY9rRKCfWDFHblpb97ET98A WPOmvU4OdoChbLQcq+0HSVjihxR7EAPh+2dyA9OTUBkyvft4i31jES4K5 iWr882KV+dYVQPbd0d/ky1JyqO/V5OQxQzRkOPUm6VUAWEFGAP8Swn05d 4=; Authentication-Results: mail3-relais-sop.national.inria.fr; dkim=none (message not signed) header.i=none; spf=SoftFail smtp.mailfrom=Paul.Zimmermann@inria.fr; spf=None smtp.helo=postmaster@coriandre Received-SPF: SoftFail (mail3-relais-sop.national.inria.fr: domain of Paul.Zimmermann@inria.fr is inclined to not designate 152.81.9.227 as permitted sender) identity=mailfrom; client-ip=152.81.9.227; receiver=mail3-relais-sop.national.inria.fr; envelope-from="Paul.Zimmermann@inria.fr"; x-sender="Paul.Zimmermann@inria.fr"; x-conformance=spf_only; x-record-type="v=spf1"; x-record-text="v=spf1 ip4:128.93.142.0/24 ip4:192.134.164.0/24 ip4:128.93.162.160 ip4:89.107.174.7 mx ~all" Received-SPF: None (mail3-relais-sop.national.inria.fr: no sender authenticity information available from domain of postmaster@coriandre) identity=helo; client-ip=152.81.9.227; receiver=mail3-relais-sop.national.inria.fr; envelope-from="Paul.Zimmermann@inria.fr"; x-sender="postmaster@coriandre"; x-conformance=spf_only X-IronPort-AV: E=Sophos;i="5.99,341,1677538800"; d="scan'208";a="53258852" Received: from coriandre.loria.fr (HELO coriandre) ([152.81.9.227]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2023 14:16:32 +0200 Date: Thu, 13 Apr 2023 14:16:31 +0200 Message-Id: From: Paul Zimmermann To: Andoni Arregi Cc: newlib@sourceware.org, andoni.arregui@gtd-gmbh.de In-Reply-To: <20230412153445.161047-1-andoni.arregui@gtd-gmbh.de> (message from Andoni Arregi on Wed, 12 Apr 2023 17:34:41 +0200) Subject: Re: [PATCH 0/4] Fix huge error for pow detected by Paul Zimmermann References: <20230412153445.161047-1-andoni.arregui@gtd-gmbh.de> X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Hi Andoni, I had time to check this patch series on top of be2749c. I confirm the issue I reported is fixed. In addition, the maximal known error, which was 636 ulps apart from the above issue, has dropped to less than 1 ulp: pow 0 -1 0x1.4c3064d46aef3p-851,-0x1.cef4118ed50c2p-10 [0.893] 0.892119 0.8921192373561432 Thank you, great work! Paul > From: Andoni Arregi > Cc: Andoni Arregi > Date: Wed, 12 Apr 2023 17:34:41 +0200 > > This patch series fixes in pow the huge error detected by Paul > Zimmermann where x is negative and y is a large odd integer. > > There is also an accuracy fix for cases where x is close to 1 and y is > large. > > Andoni Arregi (4): > Fix missing sign for overflow/underflow where x is negative and y is > large odd integer > Fix x close to 1, y between 2^31 and 2^64 > Compare j as unsigned > Replace always true if with else > > newlib/libm/math/e_pow.c | 48 +++++++++++++++++++++------------------- > 1 file changed, 25 insertions(+), 23 deletions(-) > > -- > 2.40.0 > > >