From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11189 invoked by alias); 2 May 2014 16:03:49 -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 11127 invoked by uid 48); 2 May 2014 16:03:46 -0000 From: "ktietz at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/59429] Missed optimization opportunity in qsort-style comparison functions Date: Fri, 02 May 2014 16:03:00 -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: 4.8.1 X-Bugzilla-Keywords: X-Bugzilla-Severity: minor X-Bugzilla-Who: ktietz 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: --- 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: 2014-05/txt/msg00080.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59429 --- Comment #7 from Kai Tietz --- Yeah, that was my initial idea here too. But this transformation is just an improvement for underlying unsigned one-bit values, as here the negate is indeed an nop.