From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25812 invoked by alias); 22 Apr 2009 20:37:23 -0000 Received: (qmail 25764 invoked by uid 48); 22 Apr 2009 20:37:11 -0000 Date: Wed, 22 Apr 2009 20:37:00 -0000 Message-ID: <20090422203711.25763.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug tree-optimization/39839] [4.3/4.4/4.5 regression] loop invariant motion causes stack spill In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "vmakarov at redhat dot com" 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: 2009-04/txt/msg02036.txt.bz2 ------- Comment #3 from vmakarov at redhat dot com 2009-04-22 20:37 ------- Actually YARA did not have a rematerialization as IRA. Reload has a primitive rematerialization of constant values. Although about 5 years I did implemented a register pressure relief through rematerialization which is close to Simpson's thesis. It was reported on the 2nd GCC summit. I had a mixed feeling about this: wrong register pressure calculation (because we have not cover classes at that time), small improvement but a few additional percents to compilation time. Probably it is time to return to this and make it optional or default which will eat a chunk of your recent 5% compilation time improvement :) I'll try to include this in my plans. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39839