From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1FBCFC433ED for ; Tue, 20 Apr 2021 10:57:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0B626139A for ; Tue, 20 Apr 2021 10:57:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231654AbhDTK5t (ORCPT ); Tue, 20 Apr 2021 06:57:49 -0400 Received: from mx0a-00069f02.pphosted.com ([205.220.165.32]:2136 "EHLO mx0a-00069f02.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231535AbhDTK5r (ORCPT ); Tue, 20 Apr 2021 06:57:47 -0400 X-Greylist: delayed 1747 seconds by postgrey-1.27 at vger.kernel.org; Tue, 20 Apr 2021 06:57:47 EDT Received: from pps.filterd (m0246629.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 13KARIRk031344; Tue, 20 Apr 2021 10:28:01 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=CBC0ziPweSVN+s576SbWo6o6RPOr+hWP6QgYWwVJdhc=; b=m42z1RaUhhvl+HnWHNt/YeF7dHLlr9NgCJSFcLpVEY/Lvi9yNq7luAIX5OEvc8Q7onvh WftN37mj6rbCfkMskYdz8kc/Jn/OG0abTEMvuMHJZBW5mhiDYeCRpuxPBrsoDHH6TJNN x0LsF635NNDIBcXRbukPIGbxIsA+WnrHou1lHiW4kWN0lqq+0NCTwAucKbhZNXmuXAOY dJRvQKomFbHq9G5DjhLwR/DJIfcI6G9DIL2mYwWgFTFiuBdjW+6r6a68GYHmW/GUSDE1 Jb4YfCZ4mraXTDhAnOsHyP/pc0D2NCcxEAZd55qpB14LNRQNOWE7FWP8b17TyiyQw0KE yQ== Received: from oracle.com (userp3020.oracle.com [156.151.31.79]) by mx0b-00069f02.pphosted.com with ESMTP id 381tw0g0u9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 20 Apr 2021 10:28:00 +0000 Received: from userp3020.oracle.com (userp3020.oracle.com [127.0.0.1]) by pps.podrdrct (8.16.0.36/8.16.0.36) with SMTP id 13KARxA3009216; Tue, 20 Apr 2021 10:27:59 GMT Received: from pps.reinject (localhost [127.0.0.1]) by userp3020.oracle.com with ESMTP id 3809esdbpt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 20 Apr 2021 10:27:59 +0000 Received: from userp3020.oracle.com (userp3020.oracle.com [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 13KARxL0009161; Tue, 20 Apr 2021 10:27:59 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userp3020.oracle.com with ESMTP id 3809esdbns-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 20 Apr 2021 10:27:59 +0000 Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 13KARtpk017675; Tue, 20 Apr 2021 10:27:56 GMT Received: from kadam (/102.36.221.92) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 20 Apr 2021 10:27:55 +0000 Date: Tue, 20 Apr 2021 13:27:47 +0300 From: Dan Carpenter To: David Laight Cc: "'Mauro Carvalho Chehab'" , Ashish Kalra , "devel@driverdev.osuosl.org" , Greg Kroah-Hartman , "linux-kernel@vger.kernel.org" , Sakari Ailus , "linux-media@vger.kernel.org" Subject: Re: [PATCH] media: atomisp: silence "dubious: !x | !y" warning Message-ID: <20210420102747.GB1981@kadam> References: <20210417153627.GA50228@ashish-NUC8i5BEH> <20210417205613.5c1aac74@coco.lan> <509f019decae433cab6cb367cdfa6fa9@AcuMS.aculab.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <509f019decae433cab6cb367cdfa6fa9@AcuMS.aculab.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-GUID: ajAyLqlxgs9JqJzgjE3NUwOO8J1tKu7X X-Proofpoint-ORIG-GUID: ajAyLqlxgs9JqJzgjE3NUwOO8J1tKu7X Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Sat, Apr 17, 2021 at 09:31:32PM +0000, David Laight wrote: > From: Mauro Carvalho Chehab > > Sent: 17 April 2021 19:56 > > > > Em Sat, 17 Apr 2021 21:06:27 +0530 > > Ashish Kalra escreveu: > > > > > Upon running sparse, "warning: dubious: !x | !y" is brought to notice > > > for this file. Logical and bitwise OR are basically the same in this > > > context so it doesn't cause a runtime bug. But let's change it to > > > logical OR to make it cleaner and silence the Sparse warning. > > The old code is very likely to by slightly more efficient. > > It may not matter here, but it might in a really hot path. > > Since !x | !y and !x || !y always have the same value > why is sparse complaining at all. > Smatch doesn't warn about | vs || if both sides are true/false. But I've occasionally asked people if they were trying to do a fast path optimization but it's always just a typo. regards, dan carpenter