From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2609 invoked by alias); 27 Oct 2008 16:11:12 -0000 Received: (qmail 2212 invoked by uid 48); 27 Oct 2008 16:09:50 -0000 Date: Mon, 27 Oct 2008 16:11:00 -0000 Message-ID: <20081027160950.2211.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug tree-optimization/37916] [4.2/4.3/4.4 Regression] SSA names causing register pressure; unnecessarily many simultaneously "live" names. In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "hp at gcc dot gnu dot org" 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: 2008-10/txt/msg01757.txt.bz2 ------- Comment #12 from hp at gcc dot gnu dot org 2008-10-27 16:09 ------- I had an "old" native x86_64-unknown-linux-gnu tree around from [trunk revision 139963], and I see the corresponding effect there. Of all four combinations of {,-fno-tree-reassoc} {,-fschedule-insns -fschedule-insns2}, together with -fno-ivopts -fno-reorder-blocks -fno-gcse, it was plain -fno-tree-reassoc (no scheduling) that produces the smallest stack-frame and *at a glance* smaller, faster code. (FWIW, I'm a bit surprised to see that -fschedule-insns -fschedule-insns2 is not the default for this arch.) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37916