From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7376 invoked by alias); 22 Jan 2014 15:16:36 -0000 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 Received: (qmail 7338 invoked by uid 48); 22 Jan 2014 15:16:32 -0000 From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/59811] [4.8/4.9 Regression] Huge increase in memory usage and compile time in combine Date: Wed, 22 Jan 2014 15:16:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: rtl-optimization X-Bugzilla-Version: 4.8.2 X-Bugzilla-Keywords: compile-time-hog, memory-hog X-Bugzilla-Severity: normal X-Bugzilla-Who: jakub at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.8.3 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2014-01/txt/msg02352.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59811 --- Comment #4 from Jakub Jelinek --- With -O2 -fno-automatic -ffixed-line-length-none --param sccvn-max-alias-queries-per-access=1300 the combiner completely disappears out of the picture, supposedly because then FRE/PRE doesn't give up, with 1200 the combiner already takes 17% of compile time and 77% of memory, with the default 1000 it takes 58% of compile time and 96% of memory.