>> As I said, my tests are performed on a fresly cloned copy of the Emacs 
>> repository (~5000 files).  It's not a huge project, but it's not a 
>> small one either.
>
> Hmm, both 'find' and 'git ls-files' take a little more than that on the 
> Emacs repository.
>

Not on my (not recent) development laptop...

>
> And it wouldn't be necessary of Grep had an option to limit the 
> displayed context around the match without us mucking with the regexp. 
> It would solve the issue of incorrect byte position, too.
>

I just submitted a feature request for GNU grep: 
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=47001 .  If it's accepted / 
implemented, I'll do the same for ripgrep.