From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27994 invoked by alias); 9 Feb 2015 15:07:49 -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 27830 invoked by uid 48); 9 Feb 2015 15:07:40 -0000 From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/64928] [4.8/4.9/5 Regression] Inordinate cpu time and memory usage in "phase opt and generate" with -ftest-coverage -fprofile-arcs Date: Mon, 09 Feb 2015 15:07:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: middle-end X-Bugzilla-Version: 4.9.2 X-Bugzilla-Keywords: compile-time-hog, memory-hog X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth 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: 4.8.5 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_status cf_reconfirmed_on everconfirmed 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: 2015-02/txt/msg00826.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64928 Richard Biener changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2015-02-09 Ever confirmed|0 |1 --- Comment #8 from Richard Biener --- Ok, so the memory is used by out-of-SSA it seems #5 0x0000000000c9eebc in coalesce_ssa_name () at /space/rguenther/src/svn/gcc-4_9-branch/gcc/tree-ssa-coalesce.c:1330 1330 graph = build_ssa_conflict_graph (liveinfo); (gdb) p *cl->list.htab $10 = {entries = 0x2b19b30, size = 524287, n_elements = 77146, n_deleted = 0, searches = 122189, collisions = 6508, size_prime_index = 16} where we malloc(!) 77146 entries of size 12. But of course bad is the conflict graph with 76063 bitmaps eating up around 1GB of memory for the first testcase (and function ___H__23__23_u8vector_2d__3e_object). That's likely caused by the change to more aggressively coalesce anonymous SSA names.