From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 101267 invoked by alias); 9 Mar 2018 16:17:16 -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 101258 invoked by uid 89); 9 Mar 2018 16:17:16 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.2 spammy=H*M:9925, claim X-HELO: homiemail-a82.g.dreamhost.com Subject: Re: [PATCH 2/6] Remove slow paths from sin/cos To: Wilco Dijkstra , "libc-alpha@sourceware.org" Cc: nd References: From: Siddhesh Poyarekar Message-ID: <8065ca77-ec8f-9925-7e9c-52266cd1e4c6@gotplt.org> Date: Fri, 09 Mar 2018 16:17:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-SW-Source: 2018-03/txt/msg00237.txt.bz2 On Friday 09 March 2018 09:16 PM, Wilco Dijkstra wrote: > This patch removes 2nd of the 3 range reduction cases and defer to the fi= nal one. > Input values above 2^27 are extremely rare, so this case doesn't need to = as be > optimized as smaller inputs. Please elaborate on two more points: - The basis for your claim that values above 2^27 are extremely rare, i.e. papers that you may have referred that conclude this and/or applications you may have profiled - The quantum of performance loss due to dropping the 2nd case. Thanks, Siddhesh