From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 71249 invoked by alias); 25 Aug 2015 09:14:13 -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 70169 invoked by uid 48); 25 Aug 2015 09:14:09 -0000 From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/67323] Use non-unit stride loads by preference when applicable Date: Tue, 25 Aug 2015 09:14:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: tree-optimization X-Bugzilla-Version: 6.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: rguenth at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_status cf_reconfirmed_on cc dependson assigned_to everconfirmed 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: 2015-08/txt/msg01742.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67323 Richard Biener changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |ASSIGNED Last reconfirmed| |2015-08-25 CC|richard.guenther at gmail dot com |rguenth at gcc dot gnu.org Depends on| |66721 Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #1 from Richard Biener --- Confirmed. We go down the SLP path here because the vectorizer thinks that SLP is always cheaper than using interleaving (which generally is true if there were not targets which can do the load plus interleave with load-lanes ...). I think this may be a regression as well because I enhanced SLP to apply to way more cases. Note that my plan is to make the vectorizer consider both (well, not really, but this bug shows I maybe should try), SLP and non-SLP, and evaluate based on costs which route to go. Referenced Bugs: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66721 [Bug 66721] [6 regression] gcc.target/i386/pr61403.c FAILs