From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.devel Subject: Re: [PATCH] Re: Bignum performance (was: Shrinking the C core) Date: Wed, 16 Aug 2023 07:23:11 +0200 Message-ID: <87sf8jef28.fsf@dataswamp.org> References: <87bkfartof.fsf@localhost> <175cf474-29c8-a482-072e-0de784ac59e8@gmail.com> <87o7jaqc31.fsf@localhost> <2d419e12-9239-de3e-47d0-38815a00025f@gmail.com> <87cyzqq7sx.fsf@localhost> <875y5gh075.fsf@dataswamp.org> <87zg2spcxo.fsf@localhost> <87o7j8ey0y.fsf@dataswamp.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="12405"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: emacs-devel@gnu.org Cancel-Lock: sha1:S4yW32QTNwdOmlQshtAOsovQEU4= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Wed Aug 16 13:12:36 2023 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qWES3-000312-Gb for ged-emacs-devel@m.gmane-mx.org; Wed, 16 Aug 2023 13:12:35 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qWEQy-0004E6-Jr; Wed, 16 Aug 2023 07:11:29 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qW90E-0002w2-Ra for emacs-devel@gnu.org; Wed, 16 Aug 2023 01:23:31 -0400 Original-Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qW90B-00012f-Us for emacs-devel@gnu.org; Wed, 16 Aug 2023 01:23:30 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1qW909-0009TS-I7 for emacs-devel@gnu.org; Wed, 16 Aug 2023 07:23:25 +0200 X-Injected-Via-Gmane: http://gmane.org/ Mail-Followup-To: emacs-devel@gnu.org Mail-Copies-To: never Received-SPF: pass client-ip=116.202.254.214; envelope-from=ged-emacs-devel@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -15 X-Spam_score: -1.6 X-Spam_bar: - X-Spam_report: (-1.6 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Wed, 16 Aug 2023 07:11:27 -0400 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:308810 Archived-At: tomas wrote: > Perhaps you wanted just to compute fib modulo some big power > of two? Then your program was correct, after all... So, it works for fixnums but not for bignums? The code must always work for valid indata, if it doesn't, even for a single such case, the optimization breaks the algorithm and will be removed. Maybe we can duplicate it and remove the declaration in one of them. So we would have one Fibonacci to test the speed of fixnums, and one for bignums. In the fixnums one, the declaration would still be legal. -- underground experts united https://dataswamp.org/~incal