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: Shrinking the C core Date: Sun, 27 Aug 2023 05:48:20 +0200 Message-ID: <87msyd403f.fsf@dataswamp.org> References: <20230809094655.793FC18A4654@snark.thyrsus.com> <87zg2uqdmv.fsf@localhost> <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> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="33196"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: emacs-devel@gnu.org Cancel-Lock: sha1:hp1cO4UrOx4hUsQKwcXinQ8zr3c= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Aug 27 06:20:33 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 1qa7GK-0008P1-SU for ged-emacs-devel@m.gmane-mx.org; Sun, 27 Aug 2023 06:20:32 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qa7Fa-0004oP-St; Sun, 27 Aug 2023 00:19:47 -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 1qa6lN-0007FX-DX for emacs-devel@gnu.org; Sat, 26 Aug 2023 23:48:33 -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 1qa6lK-0002KK-NZ for emacs-devel@gnu.org; Sat, 26 Aug 2023 23:48:33 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1qa6lI-0002Ba-8J for emacs-devel@gnu.org; Sun, 27 Aug 2023 05:48:28 +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: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Sun, 27 Aug 2023 00:19:46 -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:309298 Archived-At: Alfred M. Szmidt wrote: >> For example, when I write >> >> (when (> x y) (when (> x y) x)) >> >> I expect GCC JIT to throw away the duplicate comparison. > > Why do you expect that? Why do you think it is duplicate? > Where are the guarantees that > or WHEN don't have > side-effects? Do you know the exact type of X and Y so you > can skip a cascade of type checks to pick the right > comparison operator? Can you use fixnum comparison of > a specific bit width? Do you need to use bignum comparison? > > That is the type of information SBCL knows about, or allows > the user to specify. Emacs does not have that today [...] Why can SBCL answer those questions based on the sample code, and not Emacs? What is it that they have, and we don't? And why can't we have it as well? -- underground experts united https://dataswamp.org/~incal