From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27169 invoked by alias); 14 Dec 2009 10:51:40 -0000 Received: (qmail 27108 invoked by uid 48); 14 Dec 2009 10:51:27 -0000 Date: Mon, 14 Dec 2009 10:51:00 -0000 Message-ID: <20091214105127.27107.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug tree-optimization/42108] [4.4/4.5 Regression] 50% performance regression In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "dominiq at lps dot ens dot fr" Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2009-12/txt/msg01343.txt.bz2 ------- Comment #28 from dominiq at lps dot ens dot fr 2009-12-14 10:51 ------- (In reply to comment #27) > My current collection of patches and hacks for this problem. Obviously the > "if (0)" in tree-ssa-pre.c will break pr38819 again; apart from that untested, > hence probably miscompiles everything except this testcase here :-) I have not tested the patch (yet), but it seems that replacing "if(0)" with something such as "if(!flag_trapping_math)" could make everybody happy: if you don't want to break pr38819, don't use -fno-trapping-math; if you want speed, use it or use -ffast-math. Would it be acceptable? -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42108