From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13859 invoked by alias); 13 Jan 2012 19:39:19 -0000 Received: (qmail 13850 invoked by uid 22791); 13 Jan 2012 19:39:17 -0000 X-SWARE-Spam-Status: No, hits=-1.9 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from tirion.supremecenter202.com (HELO tirion.supremecenter202.com) (209.25.195.243) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 13 Jan 2012 19:39:04 +0000 Received: from c-e01ee155.46-4-64736c11.cust.bredbandsbolaget.se ([85.225.30.224]:64925 helo=[192.168.0.197]) by tirion.supremecenter202.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.69) (envelope-from ) id 1Rlmxs-000274-1G for ecos-devel@ecos.sourceware.org; Fri, 13 Jan 2012 19:39:04 +0000 Message-ID: <4F108853.4070903@siva.com.mk> Date: Fri, 13 Jan 2012 19:39:00 -0000 From: Ilija Kocho User-Agent: Mozilla/5.0 (X11; Linux i686; rv:9.0) Gecko/20111220 Thunderbird/9.0 MIME-Version: 1.0 To: ecos-devel@ecos.sourceware.org Subject: Re: Gnutools: consideration for upgrade to GCC 4.6 References: <4F106345.4080902@siva.com.mk> <4F107DE4.7080706@kuantic.com> In-Reply-To: <4F107DE4.7080706@kuantic.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-IsSubscribed: yes Mailing-List: contact ecos-devel-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-devel-owner@ecos.sourceware.org X-SW-Source: 2012-01/txt/msg00006.txt.bz2 On 13.01.2012 19:54, Bernard Fouché wrote: > > Le 13/01/2012 18:00, Ilija Kocho a écrit : >> >> Our GCC 4.3.2 is ageing and perhaps we should consider an upgrade. >> My motive is it's lacking of support for Cortex-M4 SIMD (aka DSP) and >> FPU instructions, but I think that other architectures shall gain >> from newer compiler too. I have made some signal processing tests >> with GCC 4.6.2 against current eCos compiler and they show >> performance gain even with Cortex-M3 setting, though moderate. >> Performance is considerable when Cortex-M4 setting is selected and is >> tremendous, as expected, when SIMD are used. Recently introduced >> Cortex-M products with FPU (Kinetis K70, K61, STM32F4) will further >> emphasise the benefit. >> > That sounds good! Did you try link time optimization ? I haven't changed any option except -mcpu=cortex-m4. My objective were SIMD instructions (now with K70 FPU). > I'm curious what kind of gain it could bring with a real world app. > eCos seems to fit perfectly for such an optimization, there is no > shared lib and at link time everythink is visible to the linker. Worth to try. Ilija