From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 109131 invoked by alias); 13 Mar 2018 08:46:02 -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 108849 invoked by uid 89); 13 Mar 2018 08:45:48 -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,TIME_LIMIT_EXCEEDED autolearn=unavailable version=3.3.2 spammy= X-HELO: homiemail-a56.g.dreamhost.com Subject: Re: [PATCH 6/6] Remove slow paths from sin/cos To: Wilco Dijkstra , "libc-alpha@sourceware.org" Cc: nd References: <37a3d699-e7aa-a411-f9bf-54aa1491a154@gotplt.org> From: Siddhesh Poyarekar Message-ID: <2a4f8559-9978-42ee-2b8a-df5d7335b425@gotplt.org> Date: Tue, 13 Mar 2018 08:46:00 -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: 7bit X-SW-Source: 2018-03/txt/msg00302.txt.bz2 On Monday 12 March 2018 11:01 PM, Wilco Dijkstra wrote: > I had lots of issues due to parts of functions being included in sincos.c, so I had to > disable sincos during development. The new version is much easier to maintain. That's subjective; someone half a decade down the line might differ when they see bits of code duplicated across files :) > This patch on its own gives a 16-20% speedup between 0 and 8*PI (this speedup > continues up to 2^27). The overall speedup of sincos is 48% over this range, and > between 0 and PI it is 66% faster. So I'd say specializing the small cases in sincos > gives a significant gain. That's a good rationale, please include it in your commit log. Siddhesh