From owner-freebsd-current@freebsd.org Tue Feb 9 23:15:38 2021 Return-Path: Delivered-To: freebsd-current@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 063FB52ECB2 for ; Tue, 9 Feb 2021 23:15:38 +0000 (UTC) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu [128.95.76.21]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "troutmask", Issuer "troutmask" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4DZzJm7384z4W1J; Tue, 9 Feb 2021 23:15:36 +0000 (UTC) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (localhost [127.0.0.1]) by troutmask.apl.washington.edu (8.16.1/8.16.1) with ESMTPS id 119NFTmZ059909 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Tue, 9 Feb 2021 15:15:29 -0800 (PST) (envelope-from sgk@troutmask.apl.washington.edu) Received: (from sgk@localhost) by troutmask.apl.washington.edu (8.16.1/8.16.1/Submit) id 119NFTH8059908; Tue, 9 Feb 2021 15:15:29 -0800 (PST) (envelope-from sgk) Date: Tue, 9 Feb 2021 15:15:29 -0800 From: Steve Kargl To: Dimitry Andric Cc: FreeBSD Current Subject: [PACTH,libm] hypothl(x) mishandles subnormal numbers. Message-ID: <20210209231529.GA59891@troutmask.apl.washington.edu> References: <20210206203929.GA45801@troutmask.apl.washington.edu> <20210206210448.GC45801@troutmask.apl.washington.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 4DZzJm7384z4W1J X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=washington.edu (policy=none); spf=none (mx1.freebsd.org: domain of sgk@troutmask.apl.washington.edu has no SPF policy when checking 128.95.76.21) smtp.mailfrom=sgk@troutmask.apl.washington.edu X-Spamd-Result: default: False [-2.76 / 15.00]; RCVD_TLS_ALL(0.00)[]; ARC_NA(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; FROM_HAS_DN(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[128.95.76.21:from]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; SPAMHAUS_ZRD(0.00)[128.95.76.21:from:127.0.2.255]; TO_DN_ALL(0.00)[]; NEURAL_HAM_SHORT(-0.76)[-0.757]; RCPT_COUNT_TWO(0.00)[2]; R_SPF_NA(0.00)[no SPF record]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:73, ipnet:128.95.0.0/16, country:US]; RCVD_COUNT_TWO(0.00)[2]; MAILMAN_DEST(0.00)[freebsd-current]; DMARC_POLICY_SOFTFAIL(0.10)[washington.edu : No valid SPF, No valid DKIM, none] X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Feb 2021 23:15:38 -0000 On Sat, Feb 06, 2021 at 10:32:33PM +0100, Dimitry Andric wrote: > On 6 Feb 2021, at 22:04, Steve Kargl wrote: > > > > On Sat, Feb 06, 2021 at 12:39:29PM -0800, Steve Kargl wrote: > >> I've long forgotten by freebsd bugzilla password. > >> So, if someone would like to submit a bug report, > >> here's a test program. > >> > > Forgot to include that issue was identified from > > a bug report in the OpenLibm bug mailing list. > > > > https://github.com/JuliaMath/openlibm/issues/224 > > I put this in . Now the trick is to > figure out what is going on in e_hypotl.c... :) > This patch fixes the issue. t1 is used to scale the subnormal numbers. It is generated by scaling the exponent, but that only works if t1 is 1 not 0. Index: src/e_hypotl.c =================================================================== --- src/e_hypotl.c (revision 2342) +++ src/e_hypotl.c (working copy) @@ -82,7 +82,7 @@ hypotl(long double x, long double y) man_t manh, manl; GET_LDBL_MAN(manh,manl,b); if((manh|manl)==0) return a; - t1=0; + t1=1; SET_HIGH_WORD(t1,ESW(MAX_EXP-2)); /* t1=2^(MAX_EXP-2) */ b *= t1; a *= t1; -- Steve