bug#64391: buffer narrowing slowdown regression in emacs 29

[Eli Zaretskii]

> Date: Fri, 07 Jul 2023 10:00:48 +0000
> From: Gregory Heytings <gregory@heytings.org>
> cc: acohen@ust.hk, 64391@debbugs.gnu.org, Eli Zaretskii <eliz@gnu.org>, 
>     monnier@iro.umontreal.ca, bugs@gnus.org
> 
> > I have one question about the new `with-restriction` macro: if it is 
> > intended as a convenience macro for unlabelled narrowing as well, 
> > shouldn't it then expand to the obvious
> >
> >  (save-restriction
> >    (narrow-to-region BEG END)
> >    BODY)
> >
> > instead the much more expensive call to a helper function?
> 
> Yes.  In fact now that we have a separate function for the labeled case, 
> we can remove the funcall in both cases.  Patch attached.

You are killing me.