From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30041 invoked by alias); 6 Jul 2005 14:06:00 -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 29952 invoked by alias); 6 Jul 2005 14:05:42 -0000 Date: Wed, 06 Jul 2005 14:06:00 -0000 Message-ID: <20050706140542.29951.qmail@sourceware.org> From: "dberlin at dberlin dot org" To: gcc-bugs@gcc.gnu.org In-Reply-To: <20050503114028.21356.loki@gcc.gnu.org> References: <20050503114028.21356.loki@gcc.gnu.org> Reply-To: gcc-bugzilla@gcc.gnu.org Subject: [Bug tree-optimization/21356] [4.1 Regression] Dominance error after aggressive dead code elimination (cd_dce) X-Bugzilla-Reason: CC X-SW-Source: 2005-07/txt/msg00554.txt.bz2 List-Id: ------- Additional Comments From dberlin at gcc dot gnu dot org 2005-07-06 14:05 ------- Subject: Re: [4.1 Regression] Dominance error after aggressive dead code elimination (cd_dce) On Tue, 2005-07-05 at 23:29 -0600, Jeffrey A Law wrote: > DCE in aggressive mode sometimes is able to remove control structures > and thus edge from the CFG. Sometimes removal of edges from the CFG > changes the dominator tree, but we make no attempt to actually keep > the dominators up-to-date. > > In this testcase failure to keep the dominators up-to-date leads to > a checking failure. This is trivially addressed by arranging for the > dominators to be recomputed if we remove edges from the CFG. An > enterprising individual might be able to incrementally update the > dominators, Uh, we have code to incrementally update the dominators. Just use iterate_fix_dominators -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21356