From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1360 invoked by alias); 10 Jan 2008 15:32:57 -0000 Received: (qmail 31319 invoked by uid 48); 10 Jan 2008 15:32:12 -0000 Date: Thu, 10 Jan 2008 16:00:00 -0000 Message-ID: <20080110153212.31318.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug tree-optimization/34683] [4.3 Regression] SSA rewriting in the loop unroller causes quadratic behavior In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "rguenth 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: 2008-01/txt/msg00932.txt.bz2 ------- Comment #40 from rguenth at gcc dot gnu dot org 2008-01-10 15:32 ------- After you fix this, we're back to SCCVN is slow with lots of virtual operands. For -O2 (which appearantly is the worst case) we now have the following profile: Each sample counts as 0.01 seconds. % cumulative self self total time seconds seconds calls s/call s/call name 10.33 3.08 3.08 313563133 0.00 0.00 VN_INFO 8.85 5.72 2.64 365 0.01 0.04 DFS 7.17 7.86 2.14 96368081 0.00 0.00 iterative_hash_expr 5.77 9.58 1.72 472085 0.00 0.00 valueize_vuses 5.43 11.20 1.62 216407 0.00 0.00 visit_reference_op_store 4.93 12.67 1.47 2093493 0.00 0.00 ggc_alloc_stat 3.15 13.61 0.94 17042636 0.00 0.00 set_bb_for_stmt 2.63 14.40 0.79 2442685 0.00 0.00 add_vars_for_offset 1.74 14.92 0.52 operand_build_cmp 1.54 15.38 0.46 226140 0.00 0.00 shared_vuses_from_stmt 1.48 15.82 0.44 245792 0.00 0.00 vn_reference_lookup 1.27 16.20 0.38 5272581 0.00 0.00 mark_all_vars_used_1 1.24 16.57 0.37 16115332 0.00 0.00 bitmap_set_bit 1.14 16.91 0.34 58 0.01 0.02 remove_unused_locals 1.14 17.25 0.34 6878571 0.00 0.00 htab_find_slot_with_hash 1.04 17.56 0.31 4286747 0.00 0.00 add_virtual_operand 1.04 17.87 0.31 255362 0.00 0.00 vec_gc_o_reserve_1 ... -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34683