From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28991 invoked by alias); 29 Jul 2011 07:13:40 -0000 Received: (qmail 28979 invoked by uid 22791); 29 Jul 2011 07:13:39 -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; Fri, 29 Jul 2011 07:13:25 +0000 From: "burnus at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug fortran/31067] MINLOC should sometimes be inlined (gas_dyn is sooooo sloooow) X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: fortran X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: burnus 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-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 Date: Fri, 29 Jul 2011 07:13:00 -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: 2011-07/txt/msg02518.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31067 --- Comment #46 from Tobias Burnus 2011-07-29 07:12:47 UTC --- (In reply to comment #45) [Commit to inline MINLOC/MAXLOC for a rank-1 array, which returns a single-element rank-1 array.] On my ~5 year old Athlon64 x2, I get with "-Ofast -march=native" (and with or without -fwhole-program) a performance improvement of 3% (10.72s -> 10.41s). The performance should further improve, if one fuses the loops (cf. comment 42, but also comment 34 ff.) - and if one could move the memory allocation/freeing of the automatic-array DTEMP out of the loop (after inlining). (Recall that with -fstack-arrays/-Ofast, automatic arrays are allocated on the stack.) As already mentioned indirectly in comment 0 (via PR31066): If one uses reciprocal approximation instructions and a Newton-Rhapson step (namely: -mrecip), the performance improves a lot: 6.895s. By comparison, with ifort (11.1) -xHost -O3 the run time is 7.319s.