From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 306AD3857C54; Mon, 21 Sep 2020 07:14:23 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 306AD3857C54 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1600672463; bh=xRq+8CLtKnbmK7qLyabOkxQ2hm9btroHJKnpOOuzBEs=; h=From:To:Subject:Date:In-Reply-To:References:From; b=ZfLymP/K+x9cBoovaxH//5YuKPKMm73hYuyEqfoI9FmjrSDeA9OcXLVfuK/u2xbcQ QNs30qyEeZ14pUGA/ogqlFL0QnnNQt9bmMikFWL/eYxvsAKlYuOXgUEbsZdUuq2/mO xvrvM2G2dydbzn6XDbNqPwDTg4D7nZeZ38ianeiE= From: "rguenther at suse dot de" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/96789] x264: sub4x4_dct() improves when vectorization is disabled Date: Mon, 21 Sep 2020 07:14:22 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Version: 11.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenther at suse dot de X-Bugzilla-Status: ASSIGNED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: linkw 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: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 Sep 2020 07:14:23 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96789 --- Comment #17 from rguenther at suse dot de --- On Fri, 18 Sep 2020, linkw at gcc dot gnu.org wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96789 >=20 > --- Comment #15 from Kewen Lin --- > (In reply to rguenther@suse.de from comment #14) > > On Fri, 18 Sep 2020, linkw at gcc dot gnu.org wrote: > >=20 > > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96789 > > >=20 > > > --- Comment #13 from Kewen Lin --- > > > > 2) on Power, the conversion from unsigned char to unsigned short = is nop > > > > conversion, when we counting scalar cost, it's counted, then add co= sts 32 > > > > totally onto scalar cost. Meanwhile, the conversion from unsigned s= hort to > > > > signed short should be counted but it's not (need to check why furt= her).=20 > > >=20 > > > UH to SH conversion is true when calling vect_nop_conversion_p, so it= 's not > > > even put into the cost vector.=20 > > >=20 > > > tree_nop_conversion_p's comments saying: > > >=20 > > > /* Return true iff conversion from INNER_TYPE to OUTER_TYPE generates > > > no instruction. */ > > >=20 > > > I may miss something here, but UH to SH conversion does need one expl= icit > > > extend instruction *extsh*, the precision/mode equality check looks w= rong for > > > this conversion. > >=20 > > Well, it isn't a RTL predicate and it only needs extension because > > there's never a HImode pseudo but always SImode subregs. >=20 > Thanks Richi! Should we take care of this case? or neglect this kind of > extension as "no instruction"? I was intent to handle it in target specif= ic > code, but it isn't recorded into cost vector while it seems too heavy to = do the > bb_info slp_instances revisits in finish_cost. I think it's not something we should handle on GIMPLE.=