From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail From: "J-P. Rosen" Newsgroups: comp.lang.ada Subject: Re: 64-bit unsigned integer? Date: Wed, 28 Feb 2018 07:41:28 +0100 Organization: Adalog Message-ID: References: <001e93f1-b645-4312-8a29-caca3860b560@googlegroups.com> <444f2814-d377-4c0b-8def-aee59034ee35@googlegroups.com> NNTP-Posting-Host: TKk5kT01+2w6guVcOjcsiQ.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 X-Notice: Filtered by postfilter v. 0.8.3 Content-Language: fr Xref: reader02.eternal-september.org comp.lang.ada:50699 Date: 2018-02-28T07:41:28+01:00 List-Id: Le 27/02/2018 à 19:17, Dan'l Miller a écrit : > If you are concerned about the rounding down toward negative infinity > instead of up toward zero for negative numbers, perhaps ROR and the > carry flag are more for you to fix up the rounding via the carry flag > as output (after using the CF to shift in the 0 or 1 to maintain the > 2s-complement), which is RRX on ARM. All the while avoiding the more > expensive subtraction-comparison operations. Yes, that's what I was refering to. I just took this opportunity to remind that dividing is not equivalent to a "simple" shift operation. Of course there are ways to generate correct code to fix the difference. -- J-P. Rosen Adalog 2 rue du Docteur Lombard, 92441 Issy-les-Moulineaux CEDEX Tel: +33 1 45 29 21 52, Fax: +33 1 45 29 25 00 http://www.adalog.fr