bug#64735: 29.0.92; find invocations are ~15x slower because of ignores

[Eli Zaretskii]

> From: Ihor Radchenko <yantar92@posteo.net>
> Cc: dmitry@gutov.dev, Eli Zaretskii <eliz@gnu.org>, 64735@debbugs.gnu.org,
>  sbaugh@janestreet.com
> Date: Fri, 21 Jul 2023 12:25:29 +0000
> 
> Ihor Radchenko <yantar92@posteo.net> writes:
> 
> > The question is: what is more costly
> > (a) matching complex regexp && call function or
> > (b) call function (lambda (fn) (when (and foo (match-string- ... fn)) ...))
> 
> (benchmark-run-compiled 10000000 (string-match-p (caar 
> file-name-handler-alist) "/path/to/very/deep/file"))
> ;; => (1.495432981 0 0.0)
> (benchmark-run-compiled 10000000 (funcall (lambda (fn) (and nil 
> (string-match-p (caar file-name-handler-alist) fn))) 
> "/path/to/very/deep/file"))
> ;; => (0.42053276500000003 0 0.0)
> 
> Looks like even funcall overheads are not as bad as invoking regexp search.

But "nil" is not a faithful emulation of the real test which will have
to be put there, is it?