From unknown Fri Jun 20 20:12:16 2025 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Mailer: MIME-tools 5.509 (Entity 5.509) Content-Type: text/plain; charset=utf-8 From: bug#59787 <59787@debbugs.gnu.org> To: bug#59787 <59787@debbugs.gnu.org> Subject: Status: 29.0.60; Very slow pos-visible-in-window-p with long truncated lines Reply-To: bug#59787 <59787@debbugs.gnu.org> Date: Sat, 21 Jun 2025 03:12:16 +0000 retitle 59787 29.0.60; Very slow pos-visible-in-window-p with long truncate= d lines reassign 59787 emacs submitter 59787 Eli Zaretskii severity 59787 normal thanks From debbugs-submit-bounces@debbugs.gnu.org Fri Dec 02 15:09:38 2022 Received: (at submit) by debbugs.gnu.org; 2 Dec 2022 20:09:38 +0000 Received: from localhost ([127.0.0.1]:48601 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p1CLp-0000mX-V0 for submit@debbugs.gnu.org; Fri, 02 Dec 2022 15:09:38 -0500 Received: from lists.gnu.org ([209.51.188.17]:32872) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p1CLo-0000mR-0a for submit@debbugs.gnu.org; Fri, 02 Dec 2022 15:09:36 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p1CLn-0001HB-P4 for bug-gnu-emacs@gnu.org; Fri, 02 Dec 2022 15:09:35 -0500 Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p1CLn-0000tm-BV for bug-gnu-emacs@gnu.org; Fri, 02 Dec 2022 15:09:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=Subject:To:From:Date:mime-version:in-reply-to: references; bh=sbU9aoU6DVSbHlcASBvKc3Yt7Xj0Cjwzh37prtXJc0c=; b=CAebHZh9xjncFw rDkqh4okB8Emj7ZIQCupacFiYtBtfybj0XH+NoUTVgO274ZlbnxOt1qQZjT9/lgxE3n9KvS9t+UvS FUdlToT0W3QSGBqETz8p/J9PR4BMn6DCKteqUufQnj31rWkESBvzZwW+D7cdoKVNoPuaM/Gv+LmTR Is4lQpBEdrRyCsRZkHANJXaPMLhmn6jUWtDi7tnlv7TEGExAYfp0+YzN4jhTW92igO6bzY4OV0Vm0 /1YZKCpTPGUBDmNWq8EZ8dZfehNfDWqwDN9d/kZ0pz5H7iMqtZQ7wMPMWwlqcbDdUWJAkYx8VgB0k 88Ib+z3trqOWRA+vqOKQ==; Received: from [87.69.77.57] (helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p1CLm-0003up-A2 for bug-gnu-emacs@gnu.org; Fri, 02 Dec 2022 15:09:34 -0500 Date: Fri, 02 Dec 2022 22:09:11 +0200 Message-Id: <83v8mteffc.fsf@gnu.org> From: Eli Zaretskii To: bug-gnu-emacs@gnu.org Subject: 29.0.60; Very slow pos-visible-in-window-p with long truncated lines X-Spam-Score: -2.3 (--) X-Debbugs-Envelope-To: submit X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -3.3 (---) As reported in https://debbugs.gnu.org/cgi/bugreport.cgi?bug=56682#1977: 2. after starting Isearch at a large column number, Emacs hangs up indefinitely, e.g. with 'M-g TAB 10000000 RET C-s' then even C-g doesn't get out. Debugging shows that the problem is in 'isearch-update' where the call to 'pos-visible-in-window-group-p' doesn't return. When this call is removed, the search is instantaneous. (Optimizing lazy-highlight is a separate problem in bug#56815.) The problem is that pos-visible-in-window-p starts from window-start point and goes to the POSITION passed as argument using move_it_to, which in this case is very slow, because it has all the 10000000 columns to traverse. The solution is to introduce shortcuts into pos_visible_p in this case. In GNU Emacs 29.0.60 (build 17, i686-pc-mingw32) of 2022-12-02 built on HOME-C4E4A596F7 Repository revision: 4b3eb928fed4b236d1ae06ae7d9d51a4466554d2 Repository branch: emacs-29 Windowing system distributor 'Microsoft Corp.', version 5.1.2600 System Description: Microsoft Windows XP Service Pack 3 (v5.1.0.2600) Configured using: 'configure -C --prefix=/d/usr --with-wide-int --enable-checking=yes,glyphs 'CFLAGS=-O0 -gdwarf-4 -g3'' Configured features: ACL GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 MODULES NOTIFY W32NOTIFY PDUMPER PNG RSVG SOUND SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XPM ZLIB Important settings: value of $LANG: ENU locale-coding-system: cp1255 Major mode: Lisp Interaction Minor modes in effect: tooltip-mode: t global-eldoc-mode: t eldoc-mode: t show-paren-mode: t electric-indent-mode: t mouse-wheel-mode: t tool-bar-mode: t menu-bar-mode: t file-name-shadow-mode: t global-font-lock-mode: t font-lock-mode: t blink-cursor-mode: t line-number-mode: t indent-tabs-mode: t transient-mark-mode: t auto-composition-mode: t auto-encryption-mode: t auto-compression-mode: t Load-path shadows: None found. Features: (shadow sort mail-extr dabbrev emacsbug message mailcap yank-media puny dired dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068 epg-config gnus-util text-property-search time-date subr-x mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader cl-loaddefs cl-lib sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils rmc iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel dos-w32 ls-lisp disp-table term/w32-win w32-win w32-vars term/common-win tool-bar dnd fontset image regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu timer select scroll-bar mouse jit-lock font-lock syntax font-core term/tty-colors frame minibuffer nadvice seq simple cl-generic indonesian philippine cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech european ethiopic indian cyrillic chinese composite emoji-zwj charscript charprop case-table epa-hook jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp files window text-properties overlay sha1 md5 base64 format env code-pages mule custom widget keymap hashtable-print-readable backquote threads w32notify w32 lcms2 multi-tty make-network-process emacs) Memory information: ((conses 16 43232 13224) (symbols 48 6330 6) (strings 16 16709 3199) (string-bytes 1 406733) (vectors 16 9402) (vector-slots 8 147021 11501) (floats 8 25 28) (intervals 40 273 112) (buffers 896 10)) From debbugs-submit-bounces@debbugs.gnu.org Wed Dec 07 03:23:54 2022 Received: (at 59787) by debbugs.gnu.org; 7 Dec 2022 08:23:55 +0000 Received: from localhost ([127.0.0.1]:48459 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p2pic-0000mE-M1 for submit@debbugs.gnu.org; Wed, 07 Dec 2022 03:23:54 -0500 Received: from relay4-d.mail.gandi.net ([217.70.183.196]:55579) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p2piX-0000m7-Kx for 59787@debbugs.gnu.org; Wed, 07 Dec 2022 03:23:52 -0500 Received: (Authenticated sender: juri@linkov.net) by mail.gandi.net (Postfix) with ESMTPSA id 5BE61E001C; Wed, 7 Dec 2022 08:23:40 +0000 (UTC) From: Juri Linkov To: Eli Zaretskii Subject: Re: bug#59787: 29.0.60; Very slow pos-visible-in-window-p with long truncated lines In-Reply-To: <83v8mteffc.fsf@gnu.org> (Eli Zaretskii's message of "Fri, 02 Dec 2022 22:09:11 +0200") Organization: LINKOV.NET References: <83v8mteffc.fsf@gnu.org> Date: Wed, 07 Dec 2022 09:58:40 +0200 Message-ID: <86bkofvd0v.fsf@mail.linkov.net> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/30.0.50 (x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain X-Spam-Score: -0.7 (/) X-Debbugs-Envelope-To: 59787 Cc: 59787@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -1.7 (-) > As reported in https://debbugs.gnu.org/cgi/bugreport.cgi?bug=56682#1977: > > 2. after starting Isearch at a large column number, > Emacs hangs up indefinitely, e.g. with > 'M-g TAB 10000000 RET C-s' then even C-g doesn't get out. > Debugging shows that the problem is in 'isearch-update' > where the call to 'pos-visible-in-window-group-p' doesn't return. > When this call is removed, the search is instantaneous. > (Optimizing lazy-highlight is a separate problem in bug#56815.) > > The problem is that pos-visible-in-window-p starts from window-start point > and goes to the POSITION passed as argument using move_it_to, which in this > case is very slow, because it has all the 10000000 columns to traverse. > > The solution is to introduce shortcuts into pos_visible_p in this case. Could you explain why pos-visible-in-window-p is instantaneous at any position when long lines are not truncated. Why it doesn't need to traverse 10000000 columns in this case? From debbugs-submit-bounces@debbugs.gnu.org Wed Dec 07 09:25:47 2022 Received: (at 59787) by debbugs.gnu.org; 7 Dec 2022 14:25:47 +0000 Received: from localhost ([127.0.0.1]:50494 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p2vMo-0001Pn-SJ for submit@debbugs.gnu.org; Wed, 07 Dec 2022 09:25:47 -0500 Received: from eggs.gnu.org ([209.51.188.92]:40570) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p2vMk-0001Ph-JI for 59787@debbugs.gnu.org; Wed, 07 Dec 2022 09:25:45 -0500 Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p2vMf-0001rb-2o; Wed, 07 Dec 2022 09:25:37 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=nU6ETS0qXyvSKadXC16MUjsYfALKnApodIRHSL5JdU4=; b=hyNJXOCipTa4 pQTOyDlCk/c+LbQLNJVJycSFy7YmN09bMYsQM5sZAB85WQxkywDDqJe9WjMjaP2K5GF4kXlsiAddm gWTBFtxBo4JWdk3w9kdIkyajc3a2ZtN/ol38Dt9yqP+GdUq4UnT2dMqIkgAJm3zJdGcsRU60Qvq7o GjMzMA14XRJ3eKxzuId62B5WwR6Gj+JwIIywJMOTRR1nYOK9nNfuZ5f/rxs9Y45AuwMPD04nlWhXr qQEGiJRwezH7bPAwLDlgcBt7DfEIhCPhB9un7wRUf3yAFod6Lpq7onLGxhhJOAAY31CPR/cUFhUZz /EVyY4vP4J1AXVOT7SKRug==; Received: from [87.69.77.57] (helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p2vMb-0001hC-83; Wed, 07 Dec 2022 09:25:36 -0500 Date: Wed, 07 Dec 2022 16:25:22 +0200 Message-Id: <83o7sf47fx.fsf@gnu.org> From: Eli Zaretskii To: Juri Linkov In-Reply-To: <86bkofvd0v.fsf@mail.linkov.net> (message from Juri Linkov on Wed, 07 Dec 2022 09:58:40 +0200) Subject: Re: bug#59787: 29.0.60; Very slow pos-visible-in-window-p with long truncated lines References: <83v8mteffc.fsf@gnu.org> <86bkofvd0v.fsf@mail.linkov.net> X-Spam-Score: -2.3 (--) X-Debbugs-Envelope-To: 59787 Cc: 59787@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -3.3 (---) > From: Juri Linkov > Cc: 59787@debbugs.gnu.org > Date: Wed, 07 Dec 2022 09:58:40 +0200 > > > As reported in https://debbugs.gnu.org/cgi/bugreport.cgi?bug=56682#1977: > > > > 2. after starting Isearch at a large column number, > > Emacs hangs up indefinitely, e.g. with > > 'M-g TAB 10000000 RET C-s' then even C-g doesn't get out. > > Debugging shows that the problem is in 'isearch-update' > > where the call to 'pos-visible-in-window-group-p' doesn't return. > > When this call is removed, the search is instantaneous. > > (Optimizing lazy-highlight is a separate problem in bug#56815.) > > > > The problem is that pos-visible-in-window-p starts from window-start point > > and goes to the POSITION passed as argument using move_it_to, which in this > > case is very slow, because it has all the 10000000 columns to traverse. > > > > The solution is to introduce shortcuts into pos_visible_p in this case. > > Could you explain why pos-visible-in-window-p is instantaneous at any > position when long lines are not truncated. Why it doesn't need to > traverse 10000000 columns in this case? Because when lines are wrapped, window-start is at the first visible character in the window, which is much closer to point than 10000000 characters, even with today's huge screens. And pos-visible-in-window-p starts from window-start position, because that's where it _knows_ the exact X coordinate. (It needs the X coordinate to start from so that it could report the X coordinate of point when the 3rd argument is non-nil.) By contrast, when lines are truncated and the window is hscrolled, window-start is at the first character of the first line, which in the above case is 10000000 characters before the first visible character. So starting from window-start will need to traverse 10000000 invisible characters before it gets to point. (Which if you think about it, almost suggests the shortcut for when the lines are very long...)