From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Ihor Radchenko Newsgroups: gmane.emacs.devel Subject: Re: Shrinking the C core Date: Mon, 21 Aug 2023 04:11:47 +0000 Message-ID: <87v8d95918.fsf@localhost> References: <20230809094655.793FC18A4654@snark.thyrsus.com> <87edk3gbh3.fsf@dataswamp.org> <87jztvnuyb.fsf@localhost> <875y5bdutt.fsf@dataswamp.org> <87y1i6e1uh.fsf@localhost> <874jkub40o.fsf@dataswamp.org> <87jztqdw2l.fsf@localhost> <87msym9i4r.fsf@dataswamp.org> <877cpp914t.fsf@localhost> <83fs4dwwdo.fsf@gnu.org> <874jkt90a5.fsf@localhost> <87y1i57jqi.fsf@localhost> <87pm3h7h8k.fsf@localhost> <87h6ot7cf3.fsf@localhost> <87edjx7c0b.fsf@localhost> <831qfxw2cx.fsf@gnu.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="34276"; mail-complaints-to="usenet@ciao.gmane.io" Cc: ams@gnu.org, incal@dataswamp.org, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Aug 21 06:11:48 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 1qXwGZ-0008jc-Nr for ged-emacs-devel@m.gmane-mx.org; Mon, 21 Aug 2023 06:11:47 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qXwGK-0002bu-Of; Mon, 21 Aug 2023 00:11:33 -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 1qXwG9-0002RV-L3 for emacs-devel@gnu.org; Mon, 21 Aug 2023 00:11:23 -0400 Original-Received: from mout01.posteo.de ([185.67.36.65]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qXwG6-0006fA-UT for emacs-devel@gnu.org; Mon, 21 Aug 2023 00:11:21 -0400 Original-Received: from submission (posteo.de [185.67.36.169]) by mout01.posteo.de (Postfix) with ESMTPS id BBA94240028 for ; Mon, 21 Aug 2023 06:11:16 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.net; s=2017; t=1692591076; bh=OL01wQFXqvmCtcfzMVD+nmbI6lCnWceYzndlSSsEWjM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:From; b=nocjR3uIuC5H8XbQYoTd7Bm27pqKY9YU4txljWLyoRdAZRa0DICNwP4GYGL27wjDg TRvZoph9O5DvluRy0xAELa1HJ1nX97MSDiffmXNm3u8oVGkIZb1ynfiJv1EhWeEDac AFUoNuDNS1sYVRUsVab3FwEtGe+wJ51p7T42I+EL4swuFvIwhjDQ6MmTjUUTM1F9Gp HI0Zu/slsTe1wuZXLoXd7yw7V5UtckYr8rM3pEk/eN234SkRxsJeHoxjto/bXNCzDN cqB2XqcD0v7yeJDxzMOa4N5uquUa+2uO2sg/fBcYi7MeQ9cRGbG0RcUel67+Wiy45a A4XrAE2I1WsVQ== Original-Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4RTfDN1VXpz6twB; Mon, 21 Aug 2023 06:11:16 +0200 (CEST) In-Reply-To: <831qfxw2cx.fsf@gnu.org> Received-SPF: pass client-ip=185.67.36.65; envelope-from=yantar92@posteo.net; helo=mout01.posteo.de X-Spam_score_int: -53 X-Spam_score: -5.4 X-Spam_bar: ----- X-Spam_report: (-5.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H5=-1, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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:309015 Archived-At: Eli Zaretskii writes: >> CHECK_NUMBER (n); >> if (NILP (d)) >> return FLOATP (n) ? double_to_integer (double_round (XFLOAT_DATA (n))) : n; >> ... >> During native compilation, if type information and n and d is available, >> GCC might have a chance to cut a number of branches away from the above >> code. > > Cut them how? AFAICT, none of the tests above are redundant. Consider the following: (let ((a 10)) (setq a (+ a 100)) (floor a nil)) During compilation of the above code, the compiler will know that a is a positive integer. Therefore, CHECK_NUMBER, NILP, and FLOATP are not necessary and can be omitted in the call to `floor': (let ((a 10)) (setq a (+ a 100)) a) However, GCC JIT has no information about the internal structure of the `floor' subr. Hence, it is currently unable to perform such optimization. It could, if it were somehow given an information about `floor' implementation. -- Ihor Radchenko // yantar92, Org mode contributor, Learn more about Org mode at . Support Org development at , or support my work at