From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Andrea Corallo via "Emacs development discussions." Newsgroups: gmane.emacs.devel Subject: Re: [feature/native-comp] breakage on build Date: Thu, 11 Feb 2021 14:51:53 +0000 Message-ID: References: <87lfca7lsb.fsf@russet.org.uk> <83lfc2px16.fsf@gnu.org> <87czxe45f8.fsf@russet.org.uk> <8335yap6p8.fsf@gnu.org> <87wnvm2nhb.fsf@russet.org.uk> <83wnvlod0k.fsf@gnu.org> <87wnvlmjxo.fsf@russet.org.uk> <83ft29nwc0.fsf@gnu.org> <87y2fzr8ve.fsf@russet.org.uk> <87ft26pxra.fsf@russet.org.uk> <877dnipqfh.fsf@russet.org.uk> <877dng988w.fsf@russet.org.uk> <83zh0chs13.fsf@gnu.org> <83zh0ahexe.fsf@gnu.org> Reply-To: Andrea Corallo Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="4440"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: phillip.lord@russet.org.uk, monnier@iro.umontreal.ca, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Feb 11 15:52:34 2021 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 1lADKc-00011E-3r for ged-emacs-devel@m.gmane-mx.org; Thu, 11 Feb 2021 15:52:34 +0100 Original-Received: from localhost ([::1]:35732 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lADKb-00088q-6I for ged-emacs-devel@m.gmane-mx.org; Thu, 11 Feb 2021 09:52:33 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:38194) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lADK4-0007iC-BW for emacs-devel@gnu.org; Thu, 11 Feb 2021 09:52:00 -0500 Original-Received: from mx.sdf.org ([205.166.94.24]:52156) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lADK0-0006hs-1h; Thu, 11 Feb 2021 09:52:00 -0500 Original-Received: from mab (ma.sdf.org [205.166.94.33]) by mx.sdf.org (8.15.2/8.14.5) with ESMTPS id 11BEprkA013074 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits) verified NO); Thu, 11 Feb 2021 14:51:53 GMT In-Reply-To: <83zh0ahexe.fsf@gnu.org> (Eli Zaretskii's message of "Thu, 11 Feb 2021 16:11:57 +0200") Received-SPF: pass client-ip=205.166.94.24; envelope-from=akrl@sdf.org; helo=mx.sdf.org X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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" Xref: news.gmane.io gmane.emacs.devel:264388 Archived-At: Eli Zaretskii writes: >> From: Andrea Corallo >> Cc: phillip.lord@russet.org.uk, monnier@iro.umontreal.ca, emacs-devel@gnu.org >> Date: Wed, 10 Feb 2021 20:41:07 +0000 >> >> > 4.5 min out of how much? Isn't building Emacs with native-comp take a >> > long time anyway? >> >> IIRC the full AOT build on my dev machine (8 core 16 threads) is ~19mins. > > That's 20%, not too bad. Agreed, we could also improve this with some parallelism later on, BTW I think most people will not build these AOT. >> > How about if we make the necessary assembly snippet part of the DEFUN >> > macro? Then compiling each .c file will produce those trampolines >> > ready to be used, no? (I admit that I don't really understand the >> > details of those trampolines, so maybe the above makes no sense.) >> >> Yes, that would be equivalent for a primitve foo to expand also >> something like. >> >> Lisp_Object >> Ffoo_trampoline (Lisp_Object arg1, Lisp_Object arg2) >> { >> return CALLN (Ffuncall, Qfoo, arg1, arg2); >> } >> >> At this point one need also a mechanism set the Ffoo_trampoline address >> in our link table when foo is redefined. >> >> One downside of this approach is that the binary is statically bloated >> by rarely used code. > > How many bytes is the trampoline? With 1500 primitives, we are > talking perhaps about 20KB bloat? That's not very significant, IMO. On my system each trampoline is 45K, this translates in ~65M bloat that is probably more problematic. OTOH this should be measured on Windows as it really depends on the object format I guess. Andrea