From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30495 invoked by alias); 30 Nov 2004 02:56:31 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 30472 invoked from network); 30 Nov 2004 02:56:28 -0000 Received: from unknown (HELO relay01.pair.com) (209.68.5.15) by sourceware.org with SMTP; 30 Nov 2004 02:56:28 -0000 Received: (qmail 52981 invoked from network); 30 Nov 2004 02:56:27 -0000 Received: from unknown (HELO ?192.168.123.1?) (unknown) by unknown with SMTP; 30 Nov 2004 02:56:27 -0000 X-pair-Authenticated: 24.126.73.164 Message-ID: <41ABD330.8090200@kegel.com> Date: Tue, 30 Nov 2004 03:24:00 -0000 From: Dan Kegel User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.3) Gecko/20040913 MIME-Version: 1.0 To: Will Cohen CC: law@redhat.com, GCC Mailing List Subject: Re: profile-driven optimization and the linker? References: <41A620F5.5040209@kegel.com> <1101412168.13475.19.camel@localhost.localdomain> <41AB4954.4090705@redhat.com> In-Reply-To: <41AB4954.4090705@redhat.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2004-11/txt/msg01186.txt.bz2 Will Cohen wrote: >>> http://gcc.gnu.org/news/profiledriven.html doesn't mention >>> having ld reorder sections to improve locality of reference >>> of frequently called functions. Has that technique >>> been tried with gcc and binutils? >> >> Yes. I had some success with it a while back. ... >> We had some hacks to gprof which would take profile data >> and build a linker map. That's the code that really needs >> to be improved. I never understood the gprof code well >> enough to do it right. ... > > There are a couple of students doing a ECE senior design project at > North Carolina Statue University using valgrind/callgrind to collect > call-graph information. The information is feed into a program to > generate a link script. It should do something similar to ROPE assuming > that the code is compiled with -ffunction-section. There should be some > information available on it in the near future, the NCSU semester is > wrapping up. Excellent. I'm trying to put together a similar project for a course at UCLA, and it'd be nice to be able to build on what the NCSU project did. - Dan -- Trying to get a job as a c++ developer? See http://kegel.com/academy/getting-hired.html