From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3520 invoked by alias); 8 Jun 2012 14:01:03 -0000 Received: (qmail 3329 invoked by uid 22791); 8 Jun 2012 14:01:01 -0000 X-SWARE-Spam-Status: No, hits=-4.6 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_HOSTKARMA_W,RCVD_IN_HOSTKARMA_WL,TW_HW,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from e06smtp10.uk.ibm.com (HELO e06smtp10.uk.ibm.com) (195.75.94.106) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 08 Jun 2012 14:00:45 +0000 Received: from /spool/local by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 8 Jun 2012 15:00:42 +0100 Received: from d06nrmr1507.portsmouth.uk.ibm.com (9.149.38.233) by e06smtp10.uk.ibm.com (192.168.101.140) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Fri, 8 Jun 2012 15:00:16 +0100 Received: from d06av03.portsmouth.uk.ibm.com (d06av03.portsmouth.uk.ibm.com [9.149.37.213]) by d06nrmr1507.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q58E0FR92232360; Fri, 8 Jun 2012 15:00:15 +0100 Received: from d06av03.portsmouth.uk.ibm.com (localhost.localdomain [127.0.0.1]) by d06av03.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q58E0FO4027230; Fri, 8 Jun 2012 08:00:15 -0600 Received: from [9.164.149.95] (icon-9-164-149-95.megacenter.de.ibm.com [9.164.149.95]) by d06av03.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id q58E0ERv027196; Fri, 8 Jun 2012 08:00:14 -0600 Message-ID: <4FD2056E.3060704@linux.vnet.ibm.com> Date: Fri, 08 Jun 2012 14:01:00 -0000 From: Andreas Krebbel User-Agent: Mozilla/5.0 (X11; Linux i686; rv:11.0) Gecko/20120412 Thunderbird/11.0.1 MIME-Version: 1.0 To: Richard Henderson CC: "Ryan S. Arnold" , libc-alpha@sourceware.org, libc-ports@sourceware.org Subject: Re: Include hwcap as ifunc argument References: <4FBA744A.6000702@twiddle.net> <4FBFC4EC.1060209@twiddle.net> <4FCD333E.3090107@twiddle.net> In-Reply-To: <4FCD333E.3090107@twiddle.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit x-cbid: 12060814-4966-0000-0000-00000291999F 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 X-SW-Source: 2012-06/txt/msg00019.txt.bz2 On 06/05/2012 12:14 AM, Richard Henderson wrote: > On 06/04/2012 02:21 PM, Ryan S. Arnold wrote: >> Peter Bergner reminded me today that on PowerPC the IFUNC resolver >> will most likely/often use the value in AT_PLATFORM rather than >> AT_HWCAP to determine which optimized function to use. I suppose this >> would diminish the necessity of passing the hwcap to the ifunc >> resolver. > > It depends on what's being tested, I suppose. > > Within glibc itself you've got lots of platform-specific tuning, so > you may well use AT_PLATFORM more. > > Outside glibc, it might just be a test for Altivec or VDX or whatever. >From a S/390 perspective AT_PLATFORM would also be more helpful. We do not add every new machine feature to the hwcaps vector so it is not possible to deduce the cpu level just from the hwcaps vector. I'm working on the S/390 ifunc support and hope to be able to come up with a patch soon. Bye, -Andreas-