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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 329B0C433FE for ; Wed, 19 Oct 2022 08:01:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229572AbiJSIBY convert rfc822-to-8bit (ORCPT ); Wed, 19 Oct 2022 04:01:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229864AbiJSIBU (ORCPT ); Wed, 19 Oct 2022 04:01:20 -0400 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.86.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9739E7A52F for ; Wed, 19 Oct 2022 01:01:18 -0700 (PDT) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-241-WaNyEYqdNq6hso3JXfeYOA-1; Wed, 19 Oct 2022 09:01:15 +0100 X-MC-Unique: WaNyEYqdNq6hso3JXfeYOA-1 Received: from AcuMS.Aculab.com (10.202.163.4) by AcuMS.aculab.com (10.202.163.4) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Wed, 19 Oct 2022 09:01:13 +0100 Received: from AcuMS.Aculab.com ([::1]) by AcuMS.aculab.com ([::1]) with mapi id 15.00.1497.042; Wed, 19 Oct 2022 09:01:13 +0100 From: David Laight To: 'Andy Shevchenko' , "Jason A. Donenfeld" CC: "linux-wireless@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Andrew Morton , Stanislaw Gruszka , Helmut Schaa , Kalle Valo Subject: RE: [PATCH] wifi: rt2x00: use explicitly signed type for clamping Thread-Topic: [PATCH] wifi: rt2x00: use explicitly signed type for clamping Thread-Index: AQHY4zYIcJpfOcwDCEuT6Ou0/5HWoa4VWgQQ Date: Wed, 19 Oct 2022 08:01:13 +0000 Message-ID: <0ca418f756a94859a6d32325c063f2a5@AcuMS.aculab.com> References: <202210190108.ESC3pc3D-lkp@intel.com> <20221018202734.140489-1-Jason@zx2c4.com> In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andy Shevchenko > Sent: 18 October 2022 22:10 .... > It's not a hot path as far as I understand and keeping data types aligned seems > to me worth it even if codegen is changed. IS it so awful with short? (without looking at the generated code) Why is it even short, what is wrong with int? It is extremely unlikely that the code requires any calculation results be masked to 8 (or 16) bits, but using s8 or s16 requires the compiler emit code to mask any calculated values. Remember, all C arithmetic requires promoting the values to (at least) int. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)