From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1564 invoked by alias); 12 Apr 2009 23:46:34 -0000 Received: (qmail 1532 invoked by uid 48); 12 Apr 2009 23:46:22 -0000 Date: Sun, 12 Apr 2009 23:46:00 -0000 Message-ID: <20090412234622.1531.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug rtl-optimization/39077] [4.3/4.4/4.5 Regression] GCSE-optimization causes enormous binary size increase (~20 times !) In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "steven 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: 2009-04/txt/msg01069.txt.bz2 ------- Comment #13 from steven at gcc dot gnu dot org 2009-04-12 23:46 ------- The real bug is that somehow MEM_ATTRS are not shared anymore. We have lots and lots of exactly the same expression in the table, e.g.: Index 3 (hash value 4232) (mem/s/f/c:SI (plus:SI (reg/f:SI 20 frame) (const_int -3828 [0xfffffffffffff10c])) [32 cpy.d+0 S4 A32]) Index 6 (hash value 4232) (mem/s/f/c:SI (plus:SI (reg/f:SI 20 frame) (const_int -3828 [0xfffffffffffff10c])) [32 cpy.d+0 S4 A32]) Index 10 (hash value 4232) (mem/s/f/c:SI (plus:SI (reg/f:SI 20 frame) (const_int -3828 [0xfffffffffffff10c])) [32 cpy.d+0 S4 A32]) but exp_equiv_p() thinks these are not equivalent, because the MEM_ATTRS pointers are not the same. We should have MEM_ATTRS(x)==MEM_ATTRS(y) for two MEMs with the same memory attributes, but here the pointers are not the same. So we're allocating MEM_ATTRS somewhere without going via the table, or we're adjusting MEM_ATTRS somewhere wvia an incorrect interface. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39077