From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2073 invoked by alias); 27 Jan 2011 17:45:55 -0000 Received: (qmail 2064 invoked by uid 22791); 27 Jan 2011 17:45:54 -0000 X-SWARE-Spam-Status: No, hits=-2.9 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 27 Jan 2011 17:45:48 +0000 From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/47477] [4.6 regression] Sub-optimal mov at end of method X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: rtl-optimization X-Bugzilla-Keywords: missed-optimization, ra 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: 4.6.0 X-Bugzilla-Changed-Fields: CC Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Date: Thu, 27 Jan 2011 17:58:00 -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 X-SW-Source: 2011-01/txt/msg03024.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47477 Jakub Jelinek changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |rth at gcc dot gnu.org --- Comment #4 from Jakub Jelinek 2011-01-27 17:45:33 UTC --- Alternatively, this narrowing of > word mode operations could as well be done during tree optimizations. I think the FE is the only place which performs them, as can be seen if you modify your testcase to do: void * add (void *a, void *b) { return (void *)(__INTPTR_TYPE__) ((long long)(__INTPTR_TYPE__) a + ((long long)(__INTPTR_TYPE__) b & ~1L)); } instead of void * add (void *a, void *b) { long long tmp = (long long)(__INTPTR_TYPE__) a + ((long long)(__INTPTR_TYPE__) b & ~1L); return (void *)(__INTPTR_TYPE__) tmp; } But unfortunately we have nothing which performs this later on (gimple-fold?).