From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1586 invoked by alias); 15 Oct 2004 19:24:53 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 1578 invoked from network); 15 Oct 2004 19:24:52 -0000 Received: from unknown (HELO atrey.karlin.mff.cuni.cz) (195.113.31.123) by sourceware.org with SMTP; 15 Oct 2004 19:24:52 -0000 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 29025) id 6DBAF4B45C4; Fri, 15 Oct 2004 21:24:52 +0200 (CEST) Date: Fri, 15 Oct 2004 19:24:00 -0000 From: Zdenek Dvorak To: Jakub Jelinek Cc: dnovillo@redhat.com, rth@redhat.com, gcc-patches@gcc.gnu.org Subject: Re: [PATCH] Fix PR tree-optimization/17724 (take 2) Message-ID: <20041015192452.GA6480@atrey.karlin.mff.cuni.cz> References: <20041009082440.GB22455@atrey.karlin.mff.cuni.cz> <20041009090000.GA24787@atrey.karlin.mff.cuni.cz> <20041010145645.GZ31909@devserv.devel.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20041010145645.GZ31909@devserv.devel.redhat.com> User-Agent: Mutt/1.5.6i X-SW-Source: 2004-10/txt/msg01298.txt.bz2 Hello, > On Sat, Oct 09, 2004 at 11:00:00AM +0200, Zdenek Dvorak wrote: > > this does not seem to be the right fix to me: > > > > 1) Change to delete_unreachable_blocks is not necessary. As long as > > dominators are set correctly before delete_unreachable_blocks, > > they are also set correctly after it (since removal of unreachable > > blocks cannot affect any path from entry to basic block bb, and > > immediate dominator is determined from exactly these paths). > > Are you sure that in all other cases where some basic blocks become > unreachable code that removes the edge ensures that dominators are freed > or recomputed for all basic blocks where idom(bb) could change? not completely, of course. Verify_dominators that is able to catch such problems is run on several places, so I am fairly sure we update dominators correctly most of the time, but of course there may be some more buggy places. Zdenek