From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from forward501b.mail.yandex.net (forward501b.mail.yandex.net [178.154.239.145]) (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 835303A7F7E for ; Fri, 3 Jul 2026 10:44:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.154.239.145 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783075470; cv=none; b=nvMcURUuuF3NdO7Ck9fMkJG8x8VsC2lHjkHYXHZHV4IEcNTci0NzB+Gq9YrMkEmSJriuA7roiLORAYHprxHK5REFQEUMO4ckad3nRSYyiha4KMaGgkD35v+GMbEn1woNnZoo6UubbCUVwnSkvunLL9kTtYA8zs2F4Mou/Cyzjww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783075470; c=relaxed/simple; bh=81KiIUfjR4jMhbE91DSsLXC7s7yBYWqes/C11Row2Rc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=bNhrlF6lXEYcJOL/HSbq5UhLKW6Tm207+xJelmvQG0DzIrax5ertDLd2Kw+QPYtQgiFEWHFtYQZSGCBe1vOc4HCGztdkwBOWPnPaS/NwoLNSTKhH46/R75aNsDHsY+sxEz+s149xlgRk4qS8yntLBZzJbvn9lB3/ZdAH3PrKI2E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=yandex.ru; spf=pass smtp.mailfrom=yandex.ru; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b=PbAMbFjX; arc=none smtp.client-ip=178.154.239.145 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=yandex.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=yandex.ru Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b="PbAMbFjX" Received: from mail-nwsmtp-smtp-production-main-85.iva.yp-c.yandex.net (mail-nwsmtp-smtp-production-main-85.iva.yp-c.yandex.net [IPv6:2a02:6b8:c0c:89a3:0:640:7aad:0]) by forward501b.mail.yandex.net (postfix) with ESMTPS id B5E9781503; Fri, 03 Jul 2026 13:36:31 +0300 (MSK) Received: by mail-nwsmtp-smtp-production-main-85.iva.yp-c.yandex.net (smtp) with ESMTPSA id UaeLACIfDuQ0-m0uFPYkt; Fri, 03 Jul 2026 13:36:31 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1783074991; bh=vfKyZEnQUQWW5hY6zkCiHl4Bc3JmwHUqXN9k+cslFAc=; h=From:In-Reply-To:Cc:Date:References:To:Subject:Message-ID; b=PbAMbFjXoC4I5qF9nC4tAwZWaypwoaIsNnLQRHVUUwJrYMQZbBBjiRz8ykkjSuebL 0lR2mTpddkHGadXWdo8nCEIX3MtLQF4kI7H9DN4UvhKVRT5RblwroH6mrL7EwWvtp6 srGUwyGc3yAbineoBKJH25JQ75+btRnaDCRrsMhs= Authentication-Results: mail-nwsmtp-smtp-production-main-85.iva.yp-c.yandex.net; dkim=pass header.i=@yandex.ru Message-ID: <7d763f00-b394-4467-b4cd-5b0d994d794f@yandex.ru> Date: Fri, 3 Jul 2026 13:34:16 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH -mm] kstrtox: delete division from inner parsing loop To: Alexey Dobriyan , akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, andriy.shevchenko@intel.com References: <20260703102550.501490-1-adobriyan@gmail.com> Content-Language: en-US From: Dmitry Antipov In-Reply-To: <20260703102550.501490-1-adobriyan@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 7/3/26 1:25 PM, Alexey Dobriyan wrote: > Overflow conditions can be checked on the fly resulting in at most > 2 very predictable branches and zero division instructions: > > _parse_integer_limit: > ... > mov rax, rdx > mul rsi > seto bl > add rax, rcx > mov rdx, rax > setb al Trust my word, there is a huge world beyond x86. Dmitry