From patchwork Tue Jul 5 20:06:51 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jakub Jelinek X-Patchwork-Id: 103381 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) by ozlabs.org (Postfix) with SMTP id 7BACEB6F69 for ; Wed, 6 Jul 2011 06:07:30 +1000 (EST) Received: (qmail 30898 invoked by alias); 5 Jul 2011 20:07:28 -0000 Received: (qmail 30889 invoked by uid 22791); 5 Jul 2011 20:07:27 -0000 X-SWARE-Spam-Status: No, hits=-6.5 required=5.0 tests=AWL, BAYES_00, RCVD_IN_DNSWL_HI, SPF_HELO_PASS, T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 05 Jul 2011 20:07:05 +0000 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p65K6rkK020988 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 5 Jul 2011 16:06:53 -0400 Received: from tyan-ft48-01.lab.bos.redhat.com (tyan-ft48-01.lab.bos.redhat.com [10.16.42.4]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p65K6qWq009693 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 5 Jul 2011 16:06:53 -0400 Received: from tyan-ft48-01.lab.bos.redhat.com (localhost.localdomain [127.0.0.1]) by tyan-ft48-01.lab.bos.redhat.com (8.14.4/8.14.4) with ESMTP id p65K6qE0028661; Tue, 5 Jul 2011 22:06:52 +0200 Received: (from jakub@localhost) by tyan-ft48-01.lab.bos.redhat.com (8.14.4/8.14.4/Submit) id p65K6pkx028659; Tue, 5 Jul 2011 22:06:51 +0200 Date: Tue, 5 Jul 2011 22:06:51 +0200 From: Jakub Jelinek To: Eric Botcazou Cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] Fix dead_debug_insert_before ICE (PR debug/49522) Message-ID: <20110705200651.GG2687@tyan-ft48-01.lab.bos.redhat.com> Reply-To: Jakub Jelinek References: <20110704172938.GT16443@tyan-ft48-01.lab.bos.redhat.com> <201107051035.12061.ebotcazou@adacore.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <201107051035.12061.ebotcazou@adacore.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Delivered-To: mailing list gcc-patches@gcc.gnu.org On Tue, Jul 05, 2011 at 10:35:11AM +0200, Eric Botcazou wrote: > > There are two kinds of changes we do on the debug insns without immediate > > rescanning: > > 1) reset the debug insn > > 2) replace a reg use with DEBUG_EXPR of the same mode or > > subreg of a larger DEBUG_EXPR with the same outer mode as the reg > > > > In the attached testcase on arm a debug insn is reset, because a multi-reg > > register has been used there and as the debug insn location was that > > multi-reg register before, it is now VOIDmode after the reset - (clobber > > (const_int 0)). > > That can happen only in this case, right? Otherwise, for a single register, > the debug insn would have been removed from debug->head already. If so, how > simpler would it be to remove the other uses in dead_debug_reset instead? So you prefer something like this (untested) instead? Without the second loop I have no idea how to make it work in dead_debug_reset, the other dead_debug_use referencing the same insn might be earlier or later in the chain. Jakub --- gcc/df-problems.c 2011-07-04 19:17:50.757435754 +0200 +++ gcc/df-problems.c 2011-07-05 22:04:19.817464710 +0200 @@ -3117,6 +3117,25 @@ dead_debug_reset (struct dead_debug *deb else tailp = &(*tailp)->next; } + + /* If any other dead_debug_use structs refer to the debug insns + that have been reset above, remove them too. */ + if (debug->to_rescan != NULL) + { + tailp = &debug->head; + while ((cur = *tailp)) + { + insn = DF_REF_INSN (cur->use); + if (bitmap_bit_p (debug->to_rescan, INSN_UID (insn)) + && VAR_LOC_UNKNOWN_P (INSN_VAR_LOCATION_LOC (insn))) + { + *tailp = cur->next; + XDELETE (cur); + } + else + tailp = &(*tailp)->next; + } + } } /* Add USE to DEBUG. It must be a dead reference to UREGNO in a debug