From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24365 invoked by alias); 25 Jul 2009 19:31:10 -0000 Received: (qmail 24304 invoked by uid 22791); 25 Jul 2009 19:31:09 -0000 X-SWARE-Spam-Status: No, hits=-2.4 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from smtp-outbound-2.vmware.com (HELO smtp-outbound-2.vmware.com) (65.115.85.73) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sat, 25 Jul 2009 19:31:02 +0000 Received: from mailhost2.vmware.com (mailhost2.vmware.com [10.16.67.167]) by smtp-outbound-2.vmware.com (Postfix) with ESMTP id B621959012; Sat, 25 Jul 2009 12:30:59 -0700 (PDT) Received: from [10.20.94.141] (msnyder-server.eng.vmware.com [10.20.94.141]) by mailhost2.vmware.com (Postfix) with ESMTP id 95B228E854; Sat, 25 Jul 2009 12:30:59 -0700 (PDT) Message-ID: <4A6B5BDD.80602@vmware.com> Date: Sat, 25 Jul 2009 20:48:00 -0000 From: Michael Snyder User-Agent: Thunderbird 1.5.0.12 (X11/20080411) MIME-Version: 1.0 To: Eli Zaretskii CC: Ian Lance Taylor , Jim Blandy , "dj@redhat.com" , "gcc-patches@gcc.gnu.org" , "gdb-patches@sourceware.org" Subject: Re: Add crc32 function to libiberty References: <200907242331.n6ONVqSl003646@greed.delorie.com> <83fxcl4491.fsf@gnu.org> In-Reply-To: <83fxcl4491.fsf@gnu.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2009-07/txt/msg00626.txt.bz2 Eli Zaretskii wrote: >> Cc: gcc-patches@gcc.gnu.org, gdb-patches@sourceware.org >> From: Ian Lance Taylor >> Date: Fri, 24 Jul 2009 17:40:09 -0700 >> >> Does anybody on the gdb side know the polynomial or any other >> information? > > AFAICS, this was introduced by Jim Blandy. Jim, are can you help us > here? There may be some confusion here. At least I'm confused. Jim added gnu_debuglink_crc32() to utils.c in 2003 (to be used by symfile.c), but I added static ulong crc32() to remote.c some time around 1997-1998 (argh, there's no changelog entry) while working on tracepoints. Ian's new function bears a closer resemblance to the one in remote.c than to the one in utils.c, other than the fact that it uses a pre-computed table. I'm not familiar with Jim's version, and don't know whether they compute the same result. I'm not seeking credit here -- in fact, I'd prefer to avoid it, since I frankly don't remember where I came up with the algorithm. ;-( Michael