From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Dmitry Antipov Newsgroups: gmane.emacs.devel Subject: Re: [Emacs-diffs] /srv/bzr/emacs/trunk r109327: Generalize INTERNAL_FIELD between buffers, keyboards and frames. Date: Wed, 01 Aug 2012 20:52:00 +0400 Message-ID: <50195EB0.6040504@yandex.ru> References: <50191B54.2070705@yandex.ru> <50194432.8000808@cs.ucla.edu> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: dough.gmane.org 1343839946 16387 80.91.229.3 (1 Aug 2012 16:52:26 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Wed, 1 Aug 2012 16:52:26 +0000 (UTC) Cc: emacs-devel@gnu.org To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Aug 01 18:52:24 2012 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 1Swc9l-0000aq-6J for ged-emacs-devel@m.gmane.org; Wed, 01 Aug 2012 18:52:21 +0200 Original-Received: from localhost ([::1]:36659 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Swc9k-0000Ob-IG for ged-emacs-devel@m.gmane.org; Wed, 01 Aug 2012 12:52:20 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:46424) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Swc9d-0000Nw-Df for emacs-devel@gnu.org; Wed, 01 Aug 2012 12:52:19 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Swc9X-00080k-JP for emacs-devel@gnu.org; Wed, 01 Aug 2012 12:52:13 -0400 Original-Received: from forward18.mail.yandex.net ([95.108.253.143]:36987) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Swc9X-00080b-3A for emacs-devel@gnu.org; Wed, 01 Aug 2012 12:52:07 -0400 Original-Received: from smtp18.mail.yandex.net (smtp18.mail.yandex.net [95.108.252.18]) by forward18.mail.yandex.net (Yandex) with ESMTP id 8F0131781908; Wed, 1 Aug 2012 20:52:02 +0400 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1343839922; bh=3kK0zuqMpP1ch+/+vsusyDiEEkH0nk+5veEKl+IPMdI=; h=Message-ID:Date:From:MIME-Version:To:CC:Subject:References: In-Reply-To:Content-Type:Content-Transfer-Encoding; b=AGYIUM3VQ33er18IVnqhYpvGNM/nfa14XoRxNullcxuEBMmznO51Gsau43hcRhO2/ +GtlEE1G0AhtS3EljlWiaHn96BqftF618yi7PnfdUE6AwMm6dfbuOQEhH17XDwXuEr AvfK75v6HrFa5Azriw5BB0Wvy5rwLwnv+ULwWQho= Original-Received: from smtp18.mail.yandex.net (localhost [127.0.0.1]) by smtp18.mail.yandex.net (Yandex) with ESMTP id 6AB3218A01D1; Wed, 1 Aug 2012 20:52:02 +0400 (MSK) Original-Received: from 167.gprs.mts.ru (167.gprs.mts.ru [213.87.132.167]) by smtp18.mail.yandex.net (nwsmtp/Yandex) with ESMTP id q0J4lFA7-q1JSAtGO; Wed, 1 Aug 2012 20:52:01 +0400 X-Yandex-Rcpt-Suid: eggert@cs.ucla.edu X-Yandex-Rcpt-Suid: emacs-devel@gnu.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1343839922; bh=3kK0zuqMpP1ch+/+vsusyDiEEkH0nk+5veEKl+IPMdI=; h=Message-ID:Date:From:User-Agent:MIME-Version:To:CC:Subject: References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=CPuefrcKAwDfZuXLexATbwf7Jr6nnFxYUPOVJIgyv5GvlFX1MdXXyhzYnaKZ6sirR azOfdTJCs2yh9BAs22U2SCJi24/uirMhbDlY4LanVjNU0ZMmBjDgYeFAHUEMopGVWr gpmYg8Mgsvyu7YUHTGoqH2a24l8y6ob06tq1GL6U= User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:14.0) Gecko/20120713 Thunderbird/14.0 In-Reply-To: <50194432.8000808@cs.ucla.edu> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 95.108.253.143 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:152085 Archived-At: On 08/01/2012 06:58 PM, Paul Eggert wrote: > OK, but why bother to do the hugely overestimated > write barrier that FVAR implies? Surely that is not > what is wanted here, for the garbage collector. As I > understand it, what's really wanted for the GC is SET_FVAR. > FVAR itself might be useful in that it can be forced > to be an rvalue so that code doesn't use FVAR (...) = VAL > by mistake, but surely that is secondary. I agree, but see http://lists.gnu.org/archive/html/emacs-devel/2012-08/msg00001.html. > Stefan's point also, is that it'll be easy enough to > introduce SET_FVAR when the GC bits are ready, > and that there's no pressing need to introduce it now. I'm considering this much like a kind of chicken-egg problem: it's very hard to design GC bits without supporting infrastructure implemented, and no one wants to deal with obfuscated internal things in the absence of visible advantages provided by new GC :-). > While we're on the topic, the code is currently sloppy > about using ASET; sometimes it uses 'AREF (a, b) = c' > rather than 'ASET (a, b, c)'. I suppose this will > need fixing too. It probably should be fixed regardless > of any GC changes. Yes. BTW, there are few other things which are bad from GC's point of view: X = &AREF (obj, idx), memcpy and memmove directly between FOO->contents of struct Lisp_Vector, etc. Dmitry