From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: bignum branch Date: Fri, 03 Aug 2018 12:47:54 +0300 Message-ID: <831sbfvl11.fsf@gnu.org> References: <87o9fbbw1t.fsf@tromey.com> <86in5jdj49.fsf@gmail.com> <83wotxaiwi.fsf@gnu.org> <86k1pxmvmx.fsf@gmail.com> <87efg4a9xc.fsf@tromey.com> <87a7qr8cz7.fsf@tromey.com> <86tvoy3je9.fsf@gmail.com> <86bmb0vbxf.fsf@gmail.com> <87k1pnfcg1.fsf@tromey.com> <86sh4b1833.fsf@gmail.com> <861sbgz3dm.fsf@gmail.com> <83a7q4ufxp.fsf@gnu.org> <86in4resc8.fsf@gmail.com> NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1533289606 2621 195.159.176.226 (3 Aug 2018 09:46:46 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 3 Aug 2018 09:46:46 +0000 (UTC) Cc: emacs-devel@gnu.org To: Andy Moreton Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Aug 03 11:46:42 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1flWfR-0000Y6-Db for ged-emacs-devel@m.gmane.org; Fri, 03 Aug 2018 11:46:41 +0200 Original-Received: from localhost ([::1]:49917 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1flWhY-0007Dw-4d for ged-emacs-devel@m.gmane.org; Fri, 03 Aug 2018 05:48:52 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:34224) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1flWgq-0007Dp-QX for emacs-devel@gnu.org; Fri, 03 Aug 2018 05:48:10 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1flWgn-0004fE-MK for emacs-devel@gnu.org; Fri, 03 Aug 2018 05:48:08 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:35448) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1flWgn-0004eQ-IX; Fri, 03 Aug 2018 05:48:05 -0400 Original-Received: from [176.228.60.248] (port=2361 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1flWgm-0001JH-SR; Fri, 03 Aug 2018 05:48:05 -0400 In-reply-to: <86in4resc8.fsf@gmail.com> (message from Andy Moreton on Fri, 03 Aug 2018 10:01:59 +0100) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e 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:228120 Archived-At: > From: Andy Moreton > Date: Fri, 03 Aug 2018 10:01:59 +0100 > > > I believe your changes also cover the 32-bit MinGW build with wide ints. > > I expect so, but the build fails for 32bit MinGW builds on bignum branch > with gettimeofday problems. I have a feeling that this has already been > fixed on the master branch some time ago. Could be, but can you show the error messages? > > Can you tell what is the following hunk about? > > > >> @@ -3414,7 +3473,7 @@ Markers are converted to integers. */) > >> else > >> { > >> eassume (FIXNUMP (number)); > >> - if (XINT (number) > MOST_POSITIVE_FIXNUM) > >> + if (XINT (number) > MOST_NEGATIVE_FIXNUM) > >> XSETINT (number, XINT (number) - 1); > >> else > >> { > > The updated Fadd1 checks if the old value is MOST_POSITIVE_FIXNUM before > incrementing, as that would need a bignum result. > > This hunk in Fsub1 should check if the old value is MOST_NEGATIVE_FIXNUM > before decrementing, as that would need a bignum result. So the previous code in Fsub1 had a bug? > > Also, this: > > > >> +(defun ccl-fixnum (code) > >> + "Convert a CCL code word to a fixnum value." > >> + (- (logxor (logand code #x0fffffff) #x08000000) #x08000000)) > > The CCL compiled codewords are 28bits, but the CCL implementation > assumes that the codewords are sign-extended, so that data constants in > the upper part of the codeword are signed. This function truncates a > codeword to 28bits, and then sign extends the result to a fixnum. > > This ensures that the CCL compiler output is the same on master and > bignum branches. Yes, I know. I was asking for a comment to that effect, so that others won't wonder what this is about.