From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4492 invoked by alias); 2 Apr 2013 08:08:42 -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 4392 invoked by uid 48); 2 Apr 2013 08:08:34 -0000 From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/56766] Fails to combine (vec_select (vec_concat ...)) to (vec_merge ...) Date: Tue, 02 Apr 2013 08:08:00 -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-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: 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 X-SW-Source: 2013-04/txt/msg00076.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56766 --- Comment #1 from Richard Biener 2013-04-02 08:08:34 UTC --- Btw, vec_merge is a special-case of a non-existing vec_shuffle2. vec_merge (and a vec_suffle2) as opposed to a vec_select (vec_concat (...)) combination has the advantage that we don't need intermediate vector modes of double size. So in the long run it might be most profitable to remove vec_merge and instead introduce vec_shuffle to catch almost all vec_select (vec_concat ()) cases.