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=-2.1 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,PLING_QUERY,SPF_HELO_NONE,SPF_PASS,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 204B5C3A5A1 for ; Wed, 28 Aug 2019 12:41:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F370F2173E for ; Wed, 28 Aug 2019 12:41:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726593AbfH1Mls (ORCPT ); Wed, 28 Aug 2019 08:41:48 -0400 Received: from mail-ed1-f42.google.com ([209.85.208.42]:35621 "EHLO mail-ed1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726438AbfH1Mlr (ORCPT ); Wed, 28 Aug 2019 08:41:47 -0400 Received: by mail-ed1-f42.google.com with SMTP id t50so2882501edd.2 for ; Wed, 28 Aug 2019 05:41:45 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:subject:to:cc:references:from :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=XQb3z9P4gf099Mugft8AnZzlB0sXTeRvVgkGP0skJyk=; b=S6458ypgOU5jorIyO8hSuva+Y9SCSumx+waVFCA70BgHgcOpy/ZrCb6z/aoWy0LORL o84+uD+0zdEQ7d1zt7bLKACmiIApsFZYpZEkKWPeNt2yQwD919LgdIvt9UOMQG0tfHgF TwGQg/bGdjQywXj8VIlh4A1LPF49iehaKeoqYgB+4hPisyK6wazD3hgivofeBsch7cyx a3R/jQJ4yuU/yyrY8cNhUIt+UT9q6jAO/jfF4b9IXZ76WNZTKHKB1OksSso1WZCj65Do Z4ft2+qssjHBnGAbI4lu4xebJNpGr8fqq1pU0a4xP88KbdAbW2haBn+BHSu9kJh8Flms qGMg== X-Gm-Message-State: APjAAAUdaQwVBe1Oyn1qKThjWx9ldFXWYlB6lNTH5ZqHfCHNXL/UYGYg 4hvdyMNuDvAmWGlgELdndmE= X-Google-Smtp-Source: APXvYqz57QeeTvorHo5cXarpWRCeQpcGtAf1c3aKwtJlruwTu/+crGW/L46mB112EyJC75bvpTlxgw== X-Received: by 2002:a50:fd10:: with SMTP id i16mr3650722eds.97.1566996105050; Wed, 28 Aug 2019 05:41:45 -0700 (PDT) Received: from [10.10.2.174] (bran.ispras.ru. [83.149.199.196]) by smtp.gmail.com with ESMTPSA id 59sm440043edg.44.2019.08.28.05.41.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 28 Aug 2019 05:41:44 -0700 (PDT) Reply-To: efremov@linux.com Subject: Re: [PATCH] scripts: coccinelle: check for !(un)?likely usage To: Julia Lawall Cc: Joe Perches , cocci@systeme.lip6.fr, linux-kernel@vger.kernel.org, Gilles Muller , Nicolas Palix , Michal Marek References: <20190825130536.14683-1-efremov@linux.com> <88f6e48e-1230-9488-a973-397f4e6dfbb5@linux.com> <4E9DDF9E-C883-44F0-A3F4-CD49284DB60D@lip6.fr> From: Denis Efremov Message-ID: <496b3d09-47a2-3836-2899-d964267993d3@linux.com> Date: Wed, 28 Aug 2019 15:41:43 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <4E9DDF9E-C883-44F0-A3F4-CD49284DB60D@lip6.fr> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > As a human I am confused. Is !likely(x) equivalent to x or !x? > > Julia > As far as I could understand it: # define likely(x) __builtin_expect(!!(x), 1) !likely(x) !__builtin_expect(!!(x), 1) !((!!(x)) == 1) (!!(x)) != 1, since !! could result in 0 or 1 (!!(x)) == 0 !(!!(x)) !!!(x) !(x) Thanks, Denis