From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by sourceware.org (Postfix) with ESMTP id 7168E3846074 for ; Tue, 9 Feb 2021 13:30:51 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 7168E3846074 Received: from mail-qk1-f197.google.com (mail-qk1-f197.google.com [209.85.222.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-378-uJexbX7HPJytvgexvxYkdA-1; Tue, 09 Feb 2021 08:30:49 -0500 X-MC-Unique: uJexbX7HPJytvgexvxYkdA-1 Received: by mail-qk1-f197.google.com with SMTP id s4so15684186qkj.18 for ; Tue, 09 Feb 2021 05:30:49 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=IQKHhip73kdf1KZTH6qcunA7qUWwnuhfBklVdnJ00jo=; b=L1W6ATmhj6YzkGwFeOB1QmlR3c8WzD8n4EGVNH6rlhIoCXEeQh6I0FYoWQVsQDatCO 7T+E0JTPQRKm05BSm6GwsfozXeBz77c+DkhOWgM0kMHP0JWM4lYtIBQg+/LFDPKyKV+p 4eZpStD6b0964KW3ywVS+UBVFpLbhqHxhr/T4MDNQb1xDc80AHEerTcznNi0ORwv+gFM MsUMDt0Yx19Ue+mu1IPldjy3uJGdUPXJgUgUOEcUkWKBfTmpoVoS5drAd8Ona5GUqrvS EQ/p2zNjuUP0hWBqKH4xnSl9HyXriNjzprgAxCr6Y3V3uN1bk8Dxbspq8ToKD4ApWeSf R8Qg== X-Gm-Message-State: AOAM532sSss9EUDGrqQ4S+p4hyKMJCwKGMyq8vcJ6DtVq9Li3x6kUQdI oRsxCkY1Fa11BLVrgfUtP3ohPQWhTYrgyV/ejBVUTZ3DvvHh8U2rNL9TS9shH32/Dc1l9yAJfdc 5kyJJcT1D64ebzcJatk2N3t8VSr0SHsoAcrGo0+XylY5IxboKDHFtYkkbK1z2jqEErcdjig== X-Received: by 2002:a05:622a:248:: with SMTP id c8mr19295932qtx.122.1612877448615; Tue, 09 Feb 2021 05:30:48 -0800 (PST) X-Google-Smtp-Source: ABdhPJwjz0q2zy9cBQEwl02vDKZgv9p5Zdjj0Y9IWkkwoWdy0FljZKB/A9eW4iAm38hW/xNabz118Q== X-Received: by 2002:a05:622a:248:: with SMTP id c8mr19295911qtx.122.1612877448389; Tue, 09 Feb 2021 05:30:48 -0800 (PST) Received: from [192.168.1.16] (198-84-214-74.cpe.teksavvy.com. [198.84.214.74]) by smtp.gmail.com with ESMTPSA id d1sm14362447qtq.94.2021.02.09.05.30.47 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 09 Feb 2021 05:30:47 -0800 (PST) Subject: Re: [PATCH 1/4] Add a routine for accurate reduction mod (2pi), for j0f/j1f/y0f/y1f. To: Wilco Dijkstra , paul zimmermann Cc: 'GNU C Library' References: From: Carlos O'Donell Organization: Red Hat Message-ID: <54f13253-c99e-0400-dd48-990691aef6b8@redhat.com> Date: Tue, 9 Feb 2021 08:30:46 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-5.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham 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: Tue, 09 Feb 2021 13:30:52 -0000 On 2/9/21 6:35 AM, Wilco Dijkstra via Libc-alpha wrote: > Do we really need another range reducer here? Would it be possible to use the > much faster reduce_fast and reduce_large in sysdeps/ieee754/flt-32/s_sincosf.h? > Given that returns a 62-bit modulo of PI/4, it should be more accurate as well. Paul and I were talking about this off-list, and my opinion was that we did not need to block this patch on this issue. I believe the range reducer here is *more* accurate than the one used for sincos, so there would be a difference. Refactoring to have one range reducer with sufficient accuracy to meet the needs of both set of functions should not be a blocker for inclusion. -- Cheers, Carlos.