From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30964 invoked by alias); 25 Mar 2003 18:13:53 -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 30942 invoked from network); 25 Mar 2003 18:13:53 -0000 Received: from unknown (HELO igw2.watson.ibm.com) (129.34.20.6) by sources.redhat.com with SMTP; 25 Mar 2003 18:13:53 -0000 Received: from sp1n293en1.watson.ibm.com (sp1n293en1.watson.ibm.com [9.2.112.57]) by igw2.watson.ibm.com (8.11.6/8.11.4) with ESMTP id h2PIDmT257874; Tue, 25 Mar 2003 13:13:48 -0500 Received: from makai.watson.ibm.com (makai.watson.ibm.com [9.2.216.144]) by sp1n293en1.watson.ibm.com (8.11.6/8.11.4) with ESMTP id h2PIDml96302; Tue, 25 Mar 2003 13:13:48 -0500 Received: from watson.ibm.com (localhost [127.0.0.1]) by makai.watson.ibm.com (AIX4.3/8.9.3/8.9.3/09-18-2002) with ESMTP id NAA30690; Tue, 25 Mar 2003 13:13:48 -0500 Message-Id: <200303251813.NAA30690@makai.watson.ibm.com> To: Alan Modra cc: gcc@gcc.gnu.org Subject: Re: REQ_EQUAL and mems hoisted out of loops In-Reply-To: Message from Alan Modra of "Tue, 25 Mar 2003 22:42:16 +1030." <20030325121216.GL931@bubble.sa.bigpond.net.au> Date: Tue, 25 Mar 2003 18:27:00 -0000 From: David Edelsohn X-SW-Source: 2003-03/txt/msg01547.txt.bz2 >>>>> Alan Modra writes: Alan> Oops, reg 145 has changed in the meantime at insn 41. From what I can Alan> tell, the REG_EQUAL notes in combination with the fact that the store Alan> to "y" has been moved out of the loop by loop optimization, is the cause Alan> of cse confusion. Alan> So it seems a possible fix would be to delete all REG_EQUAL notes Alan> that mention any mem hoisted out of a loop. Before I try to do that, Alan> I thought I'd solicit comments on the approach. Reasonable? Sounds similar to a previous unroller bug I tracked down where a REG_EQUAL note no longer was valid: http://gcc.gnu.org/ml/gcc-patches/2002-10/msg00269.html David