bug#45248: 28.0.50; Emacs freezes with big C functions

[Ravine Var]

Scrolling through large functions freezes Emacs. For example,
the function proto_register_rrc(void) extracted from Wireshark
shows the issue.

https://gitlab.com/wireshark/wireshark/-/raw/master/epan/dissectors/packet-rrc.c

Profile report with emacs -Q:

https://gist.github.com/ravine-var/9136ed2608a08f65111bdc2fc531ccf5

In GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, cairo version 1.17.4)
 of 2020-12-15 built on ryzen-mach
Repository revision: fd4297b25a61b33340ef312355748512e702bc2c
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12010000
System Description: Arch Linux

Configured using:
 'configure --prefix=/usr/local --without-rsvg --with-x-toolkit=no
 --without-lcms2 --without-libsystemd --without-dbus --without-gsettings
 --without-selinux --with-sound=no --enable-link-time-optimization
 'CFLAGS=-O2 -march=native''

Configured features:
XPM JPEG TIFF GIF PNG CAIRO NOTIFY INOTIFY ACL GNUTLS LIBXML2 FREETYPE
HARFBUZZ ZLIB OLDXMENU X11 XDBE XIM MODULES THREADS PDUMPER

Important settings:
  value of $LANG: en_IN.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Dired by name

Minor modes in effect:
  save-place-mode: t
  savehist-mode: t
  dired-omit-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  column-number-mode: 1
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
~/packages/xcscope/xcscope hides /usr/share/emacs/site-lisp/xcscope
~/packages/dictionary-el/dictionary hides 
/usr/local/share/emacs/28.0.50/lisp/net/dictionary

Features:
(shadow face-remap emacsbug dired-aux cl-extra help-mode edmacro kmacro
emms-browser sort emms-playlist-sort emms-last-played emms-cache
emms-volume emms-volume-mixerctl emms-volume-pulse emms-volume-amixer
emms-info-libtag emms-info emms-later-do emms-player-simple
emms-playlist-mode emms-source-playlist emms-source-file locate emms
emms-compat saveplace savehist visual-fill-column mu4e-contrib eshell
esh-cmd esh-ext esh-opt esh-proc esh-io esh-arg esh-module esh-groups
esh-util bookmark pp mu4e mu4e-org mu4e-main mu4e-view thingatpt
mu4e-headers mu4e-compose mu4e-context mu4e-draft mu4e-actions ido
rfc2368 smtpmail sendmail mu4e-mark mu4e-proc mu4e-utils doc-view
jka-compr image-mode exif mu4e-lists mu4e-message shr kinsoku svg xml
dom browse-url url url-proxy url-privacy url-expand url-methods
url-history url-cookie url-domsuf url-util url-parse url-vars mailcap
flow-fill org ob ob-tangle ob-ref ob-lob ob-table ob-exp org-macro
org-footnote org-src ob-comint org-pcomplete pcomplete comint ansi-color
org-list org-faces org-entities noutline outline easy-mmode org-version
ob-emacs-lisp ob-core ob-eval org-table ol org-keys org-compat advice
org-macs org-loaddefs format-spec find-func cal-menu calendar
cal-loaddefs mule-util hl-line mu4e-vars message rmc puny rfc822 mml
mml-sec epa derived epg epg-config gnus-util rmail rmail-loaddefs
auth-source cl-seq eieio eieio-core cl-macs eieio-loaddefs
password-cache json map text-property-search time-date subr-x seq
byte-opt gv bytecomp byte-compile cconv mm-decode mm-bodies mm-encode
mail-parse rfc2231 rfc2047 rfc2045 mm-util ietf-drums mail-prsvr
mailabbrev mail-utils gmm-utils mailheader cl-loaddefs cl-lib mu4e-meta
dictionary link connection cycbuf dired-x dired dired-loaddefs xcscope
ring easymenu iso-transl tooltip eldoc electric uniquify ediff-hook
vc-hooks lisp-float-type mwheel term/x-win x-win term/common-win x-dnd
tool-bar dnd fontset image regexp-opt fringe tabulated-list replace
newcomment text-mode elisp-mode lisp-mode prog-mode register page
tab-bar menu-bar rfn-eshadow isearch timer select scroll-bar mouse
jit-lock font-lock syntax facemenu font-core term/tty-colors frame
minibuffer cl-generic 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 charscript charprop case-table epa-hook jka-cmpr-hook help
simple abbrev obarray cl-preloaded nadvice button loaddefs faces
cus-face macroexp files window text-properties overlay sha1 md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote threads inotify dynamic-setting font-render-setting cairo x
multi-tty make-network-process emacs)

Memory information:
((conses 16 145029 10616)
 (symbols 48 16107 1)
 (strings 32 54243 2983)
 (string-bytes 1 1799965)
 (vectors 16 28914)
 (vector-slots 8 327029 18380)
 (floats 8 151 158)
 (intervals 56 538 134)
 (buffers 984 12))