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[92.21.58.28]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3b5e8e2747fsm1472931f8f.100.2025.07.10.03.35.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Jul 2025 03:35:07 -0700 (PDT) Date: Thu, 10 Jul 2025 11:35:04 +0100 From: David Laight To: "Li,Rongqing" Cc: Andrew Morton , "linux-kernel@vger.kernel.org" , "u.kleine-koenig@baylibre.com" , "Nicolas Pitre" , Oleg Nesterov , Peter Zijlstra , Biju Das , "rostedt@goodmis.org" Subject: Re: [????] Re: [PATCH v3 next 09/10] lib: mul_u64_u64_div_u64() Optimise the divide code Message-ID: <20250710113504.583a3721@pumpkin> In-Reply-To: <08a4b591e9ee41ca8cec888772a0fc43@baidu.com> References: <20250614095346.69130-1-david.laight.linux@gmail.com> <20250614095346.69130-10-david.laight.linux@gmail.com> <20250709152420.4c95c22d@pumpkin> <08a4b591e9ee41ca8cec888772a0fc43@baidu.com> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 10 Jul 2025 09:39:51 +0000 "Li,Rongqing" wrote: ... > Nice work! > > Is it necessary to add an exception test case, such as a case for division result overflowing 64bit? Not if the code traps :-) David