From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: USE_LSB_TAG and MS-DOS Date: 18 May 2004 11:13:47 -0400 Sender: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Message-ID: References: <2719-Sat15May2004150718+0300-eliz@gnu.org> <2914-Tue18May2004170058+0300-eliz@gnu.org> NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1084899675 31170 80.91.224.253 (18 May 2004 17:01:15 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 18 May 2004 17:01:15 +0000 (UTC) Cc: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Tue May 18 19:01:09 2004 Return-path: Original-Received: from quimby.gnus.org ([80.91.224.244]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1BQ7xl-0005CJ-00 for ; Tue, 18 May 2004 19:01:09 +0200 Original-Received: from monty-python.gnu.org ([199.232.76.173]) by quimby.gnus.org with esmtp (Exim 3.35 #1 (Debian)) id 1BQ7xk-0007Sk-00 for ; Tue, 18 May 2004 19:01:08 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.34) id 1BQ7dg-0007SL-HK for emacs-devel@quimby.gnus.org; Tue, 18 May 2004 12:40:24 -0400 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.34) id 1BQ7d0-0007Pk-U3 for emacs-devel@gnu.org; Tue, 18 May 2004 12:39:43 -0400 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.34) id 1BQ7F4-0004Bp-E5 for emacs-devel@gnu.org; Tue, 18 May 2004 12:15:37 -0400 Original-Received: from [206.47.199.141] (helo=simmts12-srv.bellnexxia.net) by monty-python.gnu.org with esmtp (Exim 4.34) id 1BQ6Hz-0001Gx-6B; Tue, 18 May 2004 11:13:55 -0400 Original-Received: from empanada.local ([67.71.116.83]) by simmts12-srv.bellnexxia.net (InterMail vM.5.01.06.05 201-253-122-130-105-20030824) with ESMTP id <20040518151352.FCIQ15788.simmts12-srv.bellnexxia.net@empanada.local>; Tue, 18 May 2004 11:13:52 -0400 Original-Received: by empanada.local (Postfix, from userid 502) id AEAEC19275A; Tue, 18 May 2004 11:13:48 -0400 (EDT) Original-To: Eli Zaretskii In-Reply-To: <2914-Tue18May2004170058+0300-eliz@gnu.org> Original-Lines: 26 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.4 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Xref: main.gmane.org gmane.emacs.devel:23637 X-Report-Spam: http://spam.gmane.org/gmane.emacs.devel:23637 > I found the villain: dos-unsupported-char-glyph was being initialized > with a literal numerical value instead of going thru make_number. >>From the ChangeLog text it seems that cmpiling with USE_LISP_UNION_TYPE would have caught that eons ago. > Btw, is pure[] usage supposed to go up when USE_LSB_TAG is in effect? > AFAICS, it went from 977KB to 1019KB with almost no changes in Lisp > files since the previous build. There is likely to be an increase of about "2bytes * nb objects" due to the additional alignment constraint. Actually, most objects have a size that's a multiple of 8, so the extra alignment should only happen after allocating an array or a string, so it's probably more like "2b * nb arrays-or-strings". Stefan PS: Reminds me I have a local hack to save space for small strings and pure strings where the string data is placed at the end of the string object rather than going through an indirection. This saves 4bytes per pure string (about 70KB in my case IIRC). And it saves 8 bytes per string of 3bytes or less (on 32bit machines) and of 7bytes or less (on 64 machines). Strings of 3bytes or less account for almost half of all the strings ever allocated, IIRC.