Subject: bug#18777: [PATCH] dfa: improvement for checking of multibyte character boundary

From: Paul Eggert <[email-masked]>
Date: Wed, 17 Dec 2014 09:46:09 -0800

On 12/17/2014 09:21 AM, Norihiro Tanaka wrote:
> If WCP != NULL, all of following code will be pruned, although I think
> that it is ignorable for the performance.
>
>    if (wcp == NULL && always_character_boundary[*p])
>      return p;

Yes, and that's the point: we don't want this if-statement to be pruned 
if WCP != NULL.  We want the code to return P right away in the typical 
case where P is at a character boundary.  If MBP is way less than P, 
this will save the work of the following loop.