Subject: 25.0.95; forward-comment backwards takes O(n^2)
From: Leo Liu <[email-masked]>
To: [email-masked]
Date: Sun, 17 Jul 2016 19:04:18 +0800
List-Id: <debbugs-submit.debbugs.gnu.org>

1. Use the attached file as an example, open it in emacs in ruby-mode
2. Move point to end of buffer and eval (forward-comment (- (point)))

The last step takes about 0.25 seconds on my MacBook 3 GHz Intel Core
i7. If you double the lines of comments, the time increase by 4 folds.

Any idea why forward-comment backwards is so slow?

Leo