From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Fabrice Popineau Newsgroups: gmane.emacs.devel Subject: Re: C and Emacs Lisp code parts Date: Sat, 2 Jul 2016 16:41:05 +0000 (UTC) Message-ID: References: <624c3d37-c829-7187-a699-7d7bbc211a20@online.de> <83ziq1u668.fsf@gnu.org> <83y45lu2up.fsf@gnu.org> <54f5d80c-f20b-31aa-b438-401984fcb5b8@online.de> <874m89crw3.fsf@red-bean.com> <58c6fa18-d636-1498-8d37-b435c4ee8ec9@online.de> <83r3bdth7f.fsf@gnu.org> <06dfdf82-c469-8abe-15ab-22a96e64070b@online.de> <83mvm1tg0g.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1467477741 2573 80.91.229.3 (2 Jul 2016 16:42:21 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 2 Jul 2016 16:42:21 +0000 (UTC) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Jul 02 18:42:12 2016 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 1bJNzf-0005Wh-4S for ged-emacs-devel@m.gmane.org; Sat, 02 Jul 2016 18:42:11 +0200 Original-Received: from localhost ([::1]:39319 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bJNze-0004M6-7N for ged-emacs-devel@m.gmane.org; Sat, 02 Jul 2016 12:42:10 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:41192) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bJNyr-00040G-BH for emacs-devel@gnu.org; Sat, 02 Jul 2016 12:41:23 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bJNyn-0006JB-7j for emacs-devel@gnu.org; Sat, 02 Jul 2016 12:41:20 -0400 Original-Received: from plane.gmane.org ([80.91.229.3]:42060) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bJNyn-0006J6-0n for emacs-devel@gnu.org; Sat, 02 Jul 2016 12:41:17 -0400 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1bJNyh-0005Aq-K1 for emacs-devel@gnu.org; Sat, 02 Jul 2016 18:41:11 +0200 Original-Received: from 131.233.29.93.rev.sfr.net ([93.29.233.131]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sat, 02 Jul 2016 18:41:11 +0200 Original-Received: from fabrice.popineau by 131.233.29.93.rev.sfr.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sat, 02 Jul 2016 18:41:11 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 24 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: sea.gmane.org User-Agent: Loom/3.14 (http://gmane.org/) X-Loom-IP: 93.29.233.131 (Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 80.91.229.3 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 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" Xref: news.gmane.org gmane.emacs.devel:205088 Archived-At: Eli Zaretskii gnu.org> writes: > As for font-lock, its features are based on regular expression and > syntax tables, both of which are implemented in C as well. The fact that regexp are implemented in C is not a guarantee of the best speed. Some years ago, when the Common Lisp CL-PPCRE library appeared, it was benchmarked 5-20 times faster than C regexp libraries, because the automaton was compiled directly to machine code, whereas the C counterpart had to do lookups into the table that describes the automaton. I am no specialist of the the current variants of regexp libraries but some of them seem to make use of jit compiler. (See http://sljit.sourceforge.net/regex_perf.html for example) So isnt't there some response time to gain around regexps? Because I don't see that src/regex.c is using a jit. Fabrice