From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from esa1.mentor.iphmx.com (esa1.mentor.iphmx.com [68.232.129.153]) by sourceware.org (Postfix) with ESMTPS id 7B43A3858D37 for ; Mon, 29 Jun 2020 22:39:57 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 7B43A3858D37 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=codesourcery.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=joseph_myers@mentor.com IronPort-SDR: vE1sVQmZoTfWhpfduPKUvdY8JE9a2h7DBSTXsfR6JnL2wu8Vcpr4+8P0TZOym55ZO5q9UGWd8X 52nV7bQMgZkX/uFmv1s7ShDEVWAc+p/FBGmsBdURKnUX4E1qWA+TIWc5ez/pz3BcFJnJaPmgbL bXQThp1qqyflEqMn3hgwEMiHiR+m3Lq4PHMRCYPVaKmv4jJ8evdm80tGA8DVSR4IPI8anAhP43 4iTnPYROj/2hykMUq3tE5XncNWF3RAmu60jFXc7o4I0zWpYtmZkmORz6LIjvJ5lKWW3tPm2e6a xoo= X-IronPort-AV: E=Sophos;i="5.75,296,1589270400"; d="scan'208";a="52571076" Received: from orw-gwy-01-in.mentorg.com ([192.94.38.165]) by esa1.mentor.iphmx.com with ESMTP; 29 Jun 2020 14:39:55 -0800 IronPort-SDR: dytj6fC7IrQU873zKNrvXNv/vI3OunZdhPI0RX5/gJmQuWI9VLv+34UeuLMkfOanFlHQcP5HTQ qS3E+25ndyTd0VOA1Ppl5JKIky6/4SvG8wzebvJH0SL0Ru6c6s35nDZ/8l5lEdkiqrjR814xYs 2gkbXLTb/fkEpWe0Tx4UZDTLiHlb/v1mbcQA37yAZgpIAtnsGY4aHsDJ5MlaCqG+z0l8+s07x2 5/J99XDBZp/4lZKJY3IdQZE2C2o2gwifncOlT1a7TWvnh6muvnAdIrCqdDw9+SJyGRCDGQXrMr Nlc= Date: Mon, 29 Jun 2020 22:39:50 +0000 From: Joseph Myers X-X-Sender: jsm28@digraph.polyomino.org.uk To: Szabolcs Nagy CC: Paul E Murphy , Subject: Re: faster expf128 In-Reply-To: <20200626100915.GN16726@arm.com> Message-ID: References: <20200626100915.GN16726@arm.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-Originating-IP: [137.202.0.90] X-ClientProxiedBy: svr-ies-mbx-06.mgc.mentorg.com (139.181.222.6) To SVR-IES-MBX-03.mgc.mentorg.com (139.181.222.3) X-Spam-Status: No, score=-3129.6 required=5.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, KAM_NUMSUBJECT, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=no autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 29 Jun 2020 22:39:58 -0000 On Fri, 26 Jun 2020, Szabolcs Nagy wrote: > > There is no expectation that most libm functions (other than those such as > > fma and sqrt that are fully defined by the corresponding IEEE operations) > > set inexact correctly. (It is necessary to set other exceptions > > correctly, and the glibc testsuite verifies that; for expf128, that's > > invalid (for signaling NaNs), overflow and underflow.) > > and presumably target specific exceptions are not considered. > (e.g. input denormal on x86) Indeed, there are no expectations that libm functions do anything in particular with those. (Those functions that manipulate the whole environment, such as fegetenv and fesetenv, should still save and restore such architecture-specific state.) -- Joseph S. Myers joseph@codesourcery.com