bug#52593: 28.0.90; (thing-at-point thing) has so much overhead since commit 7db376e560448e61485ba054def8c82b21f33d6a

[Kang Niu <isgniuk@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 2462 bytes --]

Seems now the let clause undertake the overhead:
     Samples    %   Function


        7230  77% - symbol-overlay-post-command
        7227  77%  - if
        7183  77%   - string=
        7180  77%    - symbol-overlay-get-symbol
        7180  77%     - or
        7176  77%      - thing-at-point
        7163  77%       - save-restriction
        7138  76%        - let
         221   2%         - cond
         206   2%          + let
           2   0%            let*
           7   0%         + if
          40   0%   + symbol-overlay-remove-temp
        1234  13% - command-execute
        1215  13%  - call-interactively
        1205  12%   - funcall-interactively
         783   8%    + next-line
         415   4%    + previous-line
           7   0%    + execute-extended-command
           3   0%   + byte-code
         358   3% + ...
         255   2% + redisplay_internal (C function)
         156   1% + timer-event-handler
          25   0% + undo-auto--add-boundary
          18   0% + jit-lock--antiblink-post-command
          17   0% + internal-timer-start-idle
           8   0% + clear-minibuffer-message

Lars Ingebrigtsen <larsi@gnus.org> 于2021年12月19日周日 22:44写道：

> Kang Niu <isgniuk@gmail.com> writes:
>
> > There are no fields in the buffer. (field-beginning) (field-end) return
> the same value
> > as (point-min) (point-max).
>
> Odd.  Does the following fix the performance problem?  I'm wondering
> whether it's the field functions that are slow or whether the
> narrow-to-region is the thing that somehow triggers the slowness.
>
> diff --git a/lisp/thingatpt.el b/lisp/thingatpt.el
> index 2d1bf2013e..e746d94080 100644
> --- a/lisp/thingatpt.el
> +++ b/lisp/thingatpt.el
> @@ -178,7 +178,11 @@ thing-at-point
>  See the file `thingatpt.el' for documentation on how to define
>  a symbol as a valid THING."
>    (save-restriction
> -    (narrow-to-region (field-beginning) (field-end))
> +    (let ((beg (field-beginning))
> +          (end (field-end)))
> +      (when (or (not (= beg (point-min)))
> +                (not (= end (point-max))))
> +        (narrow-to-region (field-beginning) (field-end))))
>      (let ((text
>             (cond
>              ((cl-loop for (pthing . function) in
> thing-at-point-provider-alist
>
>
> --
> (domestic pets only, the antidote for overdose, milk.)
>    bloggy blog: http://lars.ingebrigtsen.no
>

[-- Attachment #2: Type: text/html, Size: 3499 bytes --]