From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16430 invoked by alias); 8 Oct 2004 12:39:41 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org Received: (qmail 16406 invoked by alias); 8 Oct 2004 12:39:38 -0000 Date: Fri, 08 Oct 2004 12:39:00 -0000 Message-ID: <20041008123938.16405.qmail@sourceware.org> From: "dnovillo at redhat dot com" To: gcc-bugs@gcc.gnu.org In-Reply-To: <20040919165202.17560.kherron+gcc@fmailbox.com> References: <20040919165202.17560.kherron+gcc@fmailbox.com> Reply-To: gcc-bugzilla@gcc.gnu.org Subject: [Bug tree-optimization/17560] [4.0 Regression] Infinite recursion in tree-scalar-evolution with -Os X-Bugzilla-Reason: CC X-SW-Source: 2004-10/txt/msg01031.txt.bz2 List-Id: ------- Additional Comments From dnovillo at redhat dot com 2004-10-08 12:39 ------- Subject: Re: [4.0 Regression] Infinite recursion in tree-scalar-evolution with -Os On Fri, 2004-10-08 at 08:07, sebastian dot pop at cri dot ensmp dot fr wrote: > The problem is that we have a cycle "i_1 -> i_2 -> i_1" outside any > loop, and I'm not sure about the semantics of this representation. > By the way, is this a valid SSA form? > It is, but this graph is irreducible. Block #3 is only reachable via a back edge. Or put it another way, block #4 is the entry block for two different loops. Diego. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17560