From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 94416 invoked by alias); 22 Mar 2018 22:28:14 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 94404 invoked by uid 89); 22 Mar 2018 22:28:13 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,SPF_PASS,URIBL_RED autolearn=ham version=3.3.2 spammy=Hx-languages-length:587 X-HELO: relay1.mentorg.com Date: Thu, 22 Mar 2018 22:28:00 -0000 From: Joseph Myers To: Wilco Dijkstra CC: "libc-alpha@sourceware.org" , nd Subject: Re: [PATCH 3/7] sin/cos slow paths: remove slow paths from small range reduction In-Reply-To: Message-ID: References: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-ClientProxiedBy: svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) To svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) X-SW-Source: 2018-03/txt/msg00524.txt.bz2 On Wed, 21 Mar 2018, Wilco Dijkstra wrote: > This patch improves the accuracy of the range reduction. When the input is > large (2^27) and very close to a multiple of PI/2, using 110 bits of PI is not > enough. Improve range reduction accuracy to 136 bits. As a result the special > checks for results close to zero can be removed. The ULP of the polynomials is > at worst 0.55ULP, so there is no reason for the slow functions, and they can be > removed. OK. -- Joseph S. Myers joseph@codesourcery.com