From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: [Emacs-diffs] trunk r117464: Shrink Lisp_Sub_Char_Table by preferring C integers to Lisp_Objects. Date: Wed, 02 Jul 2014 14:27:23 -0400 Message-ID: References: <53B42194.2040003@yandex.ru> <53B42B2E.7090404@yandex.ru> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1404325672 20354 80.91.229.3 (2 Jul 2014 18:27:52 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 2 Jul 2014 18:27:52 +0000 (UTC) Cc: emacs-devel@gnu.org To: Dmitry Antipov Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Jul 02 20:27:43 2014 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1X2PFu-0004jk-3Q for ged-emacs-devel@m.gmane.org; Wed, 02 Jul 2014 20:27:42 +0200 Original-Received: from localhost ([::1]:55965 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X2PFt-0006p0-NS for ged-emacs-devel@m.gmane.org; Wed, 02 Jul 2014 14:27:41 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:50205) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X2PFk-0006oX-1E for emacs-devel@gnu.org; Wed, 02 Jul 2014 14:27:39 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X2PFc-0006GZ-Aw for emacs-devel@gnu.org; Wed, 02 Jul 2014 14:27:31 -0400 Original-Received: from ironport2-out.teksavvy.com ([206.248.154.181]:61228) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X2PFc-0006GR-6m for emacs-devel@gnu.org; Wed, 02 Jul 2014 14:27:24 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ArUGAIDvNVNLd+D9/2dsb2JhbABZgwaDSsA9gRcXdIIlAQEBAQIBViMQCw4mBwsUGA0kiAQI0hkXjnoHhDgEoyqFb4FqgXGBWyE X-IPAS-Result: ArUGAIDvNVNLd+D9/2dsb2JhbABZgwaDSsA9gRcXdIIlAQEBAQIBViMQCw4mBwsUGA0kiAQI0hkXjnoHhDgEoyqFb4FqgXGBWyE X-IronPort-AV: E=Sophos;i="4.97,753,1389762000"; d="scan'208";a="75815179" Original-Received: from 75-119-224-253.dsl.teksavvy.com (HELO ceviche.home) ([75.119.224.253]) by ironport2-out.teksavvy.com with ESMTP/TLS/ADH-AES256-SHA; 02 Jul 2014 14:27:23 -0400 Original-Received: by ceviche.home (Postfix, from userid 20848) id 1DC34660FA; Wed, 2 Jul 2014 14:27:23 -0400 (EDT) In-Reply-To: <53B42B2E.7090404@yandex.ru> (Dmitry Antipov's message of "Wed, 02 Jul 2014 19:54:22 +0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 206.248.154.181 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:172853 Archived-At: >> if/when we optimize the representation a bit more (i.e. merge `depth' >> and `min_char' into a single 32bit word, by adding ":2" and ":30" >> after each field), your code will probably fail. > I've considered this possible optimization too and rejected it exactly > for the reason you're talking about. But the problem is that the code is vulnerable to these kinds of changes. Why do we even need to treat such a Lisp_Sub_Char_Table as a Lisp_Vector at all? I don't see any real need for it. Stefan