From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31711 invoked by alias); 9 Sep 2013 13:39:16 -0000 Mailing-List: contact libc-ports-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: libc-ports-owner@sourceware.org Received: (qmail 31701 invoked by uid 89); 9 Sep 2013 13:39:16 -0000 Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 09 Sep 2013 13:39:16 +0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.7 required=5.0 tests=AWL,BAYES_00,KHOP_THREADED,RDNS_NONE,SPF_HELO_FAIL autolearn=no version=3.3.2 X-HELO: relay1.mentorg.com Received: from svr-orw-fem-01.mgc.mentorg.com ([147.34.98.93]) by relay1.mentorg.com with esmtp id 1VJ1gL-00049I-Ca from joseph_myers@mentor.com ; Mon, 09 Sep 2013 06:39:09 -0700 Received: from SVR-IES-FEM-02.mgc.mentorg.com ([137.202.0.106]) by svr-orw-fem-01.mgc.mentorg.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.4675); Mon, 9 Sep 2013 06:39:09 -0700 Received: from digraph.polyomino.org.uk (137.202.0.76) by SVR-IES-FEM-02.mgc.mentorg.com (137.202.0.106) with Microsoft SMTP Server id 14.2.247.3; Mon, 9 Sep 2013 14:39:08 +0100 Received: from jsm28 (helo=localhost) by digraph.polyomino.org.uk with local-esmtp (Exim 4.76) (envelope-from ) id 1VJ1gI-0007Am-RI; Mon, 09 Sep 2013 13:39:06 +0000 Date: Mon, 09 Sep 2013 13:39:00 -0000 From: "Joseph S. Myers" To: Will Newton CC: , Subject: Re: [PATCH v3] ARM: Improve armv7 memcpy performance. In-Reply-To: <522D977E.2000906@linaro.org> Message-ID: References: <522D977E.2000906@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-SW-Source: 2013-09/txt/msg00070.txt.bz2 On Mon, 9 Sep 2013, Will Newton wrote: > Only enter the aligned copy loop with buffers that can be 8-byte > aligned. This improves performance slightly on Cortex-A9 and > Cortex-A15 cores for large copies with buffers that are 4-byte > aligned but not 8-byte aligned. Did you conclude that the comment about needing unaligned word access for ldrd/strd is still accurate after this patch (and if so, for which uses)? There was a long discussion on benchmarking starting from this patch. Could you summarise the conclusions of that discussion as they relate to the appropriate benchmarks to apply to this patch, and give pointers to your before-and-after performance results? -- Joseph S. Myers joseph@codesourcery.com