From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.molgen.mpg.de (mx3.molgen.mpg.de [141.14.17.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EC94F3FC3 for ; Mon, 20 Sep 2021 08:47:30 +0000 (UTC) Received: from [192.168.0.3] (ip5f5aef72.dynamic.kabel-deutschland.de [95.90.239.114]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) (Authenticated sender: pmenzel) by mx.molgen.mpg.de (Postfix) with ESMTPSA id 0FB6E61E5FE00; Mon, 20 Sep 2021 10:47:29 +0200 (CEST) Subject: Re: [PATCH v2] lib/zlib_inflate/inffast: Check config in C to avoid unused function warning To: Christophe Leroy , Nathan Chancellor , Nick Desaulniers Cc: Zhen Lei , Andrew Morton , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev References: <20210920074633.13089-1-pmenzel@molgen.mpg.de> <00f8d7d7-cb13-203e-5a37-aee34a3258ff@csgroup.eu> From: Paul Menzel Message-ID: Date: Mon, 20 Sep 2021 10:47:28 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <00f8d7d7-cb13-203e-5a37-aee34a3258ff@csgroup.eu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Dear Christophe, Thank you for the review. Am 20.09.21 um 10:36 schrieb Christophe Leroy: > > > Le 20/09/2021 à 09:46, Paul Menzel a écrit : >> Building Linux for ppc64le with Ubuntu clang version 12.0.0-3ubuntu1~21.04.1 >> shows the warning below. >> >>      arch/powerpc/boot/inffast.c:20:1: warning: unused function 'get_unaligned16' [-Wunused-function] >>      get_unaligned16(const unsigned short *p) >>      ^ >>      1 warning generated. >> >> Fix it, by moving the check from the preprocessor to C, so the compiler >> sees the use. >> >> Signed-off-by: Paul Menzel >> --- >>   lib/zlib_inflate/inffast.c | 7 ++----- >>   1 file changed, 2 insertions(+), 5 deletions(-) >> >> diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c >> index f19c4fbe1be7..fb87a3120f0f 100644 >> --- a/lib/zlib_inflate/inffast.c >> +++ b/lib/zlib_inflate/inffast.c >> @@ -254,11 +254,8 @@ void inflate_fast(z_streamp strm, unsigned start) >>               sfrom = (unsigned short *)(from); >>               loops = len >> 1; >>               do >> -#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS >> -                *sout++ = *sfrom++; >> -#else >> -                *sout++ = get_unaligned16(sfrom++); >> -#endif >> +                *sout++ = >> IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ? >> +                *sfrom++ : get_unaligned16(sfrom++); > > I think it would be more readable as > > do { >         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) >                 *sout++ = *sfrom++; >         else >                 *sout++ = get_unaligned16(sfrom++); > } while (--loops); I prefer the ternary operator, as it’s less lines, and it’s clear, that only the variable assignment is affected by the condition. But as style is subjective, I sent v3. >>               while (--loops); >>               out = (unsigned char *)sout; >>               from = (unsigned char *)sfrom; Kind regards, Paul 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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 0A099C433F5 for ; Mon, 20 Sep 2021 08:48:03 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0373560E9C for ; Mon, 20 Sep 2021 08:48:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0373560E9C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=molgen.mpg.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4HCdVm3L1cz3036 for ; Mon, 20 Sep 2021 18:48:00 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=molgen.mpg.de (client-ip=141.14.17.11; helo=mx1.molgen.mpg.de; envelope-from=pmenzel@molgen.mpg.de; receiver=) Received: from mx1.molgen.mpg.de (mx3.molgen.mpg.de [141.14.17.11]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4HCdVG1CFpz2yJV for ; Mon, 20 Sep 2021 18:47:32 +1000 (AEST) Received: from [192.168.0.3] (ip5f5aef72.dynamic.kabel-deutschland.de [95.90.239.114]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) (Authenticated sender: pmenzel) by mx.molgen.mpg.de (Postfix) with ESMTPSA id 0FB6E61E5FE00; Mon, 20 Sep 2021 10:47:29 +0200 (CEST) Subject: Re: [PATCH v2] lib/zlib_inflate/inffast: Check config in C to avoid unused function warning To: Christophe Leroy , Nathan Chancellor , Nick Desaulniers References: <20210920074633.13089-1-pmenzel@molgen.mpg.de> <00f8d7d7-cb13-203e-5a37-aee34a3258ff@csgroup.eu> From: Paul Menzel Message-ID: Date: Mon, 20 Sep 2021 10:47:28 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <00f8d7d7-cb13-203e-5a37-aee34a3258ff@csgroup.eu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: llvm@lists.linux.dev, Zhen Lei , linux-kernel@vger.kernel.org, Paul Mackerras , Andrew Morton , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Dear Christophe, Thank you for the review. Am 20.09.21 um 10:36 schrieb Christophe Leroy: > > > Le 20/09/2021 à 09:46, Paul Menzel a écrit : >> Building Linux for ppc64le with Ubuntu clang version 12.0.0-3ubuntu1~21.04.1 >> shows the warning below. >> >>      arch/powerpc/boot/inffast.c:20:1: warning: unused function 'get_unaligned16' [-Wunused-function] >>      get_unaligned16(const unsigned short *p) >>      ^ >>      1 warning generated. >> >> Fix it, by moving the check from the preprocessor to C, so the compiler >> sees the use. >> >> Signed-off-by: Paul Menzel >> --- >>   lib/zlib_inflate/inffast.c | 7 ++----- >>   1 file changed, 2 insertions(+), 5 deletions(-) >> >> diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c >> index f19c4fbe1be7..fb87a3120f0f 100644 >> --- a/lib/zlib_inflate/inffast.c >> +++ b/lib/zlib_inflate/inffast.c >> @@ -254,11 +254,8 @@ void inflate_fast(z_streamp strm, unsigned start) >>               sfrom = (unsigned short *)(from); >>               loops = len >> 1; >>               do >> -#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS >> -                *sout++ = *sfrom++; >> -#else >> -                *sout++ = get_unaligned16(sfrom++); >> -#endif >> +                *sout++ = >> IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ? >> +                *sfrom++ : get_unaligned16(sfrom++); > > I think it would be more readable as > > do { >         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) >                 *sout++ = *sfrom++; >         else >                 *sout++ = get_unaligned16(sfrom++); > } while (--loops); I prefer the ternary operator, as it’s less lines, and it’s clear, that only the variable assignment is affected by the condition. But as style is subjective, I sent v3. >>               while (--loops); >>               out = (unsigned char *)sout; >>               from = (unsigned char *)sfrom; Kind regards, Paul