Regexec optimizations - recursive patterns

Dear porters,

Few weeks ago I made an optimizations to regexec in case of many capture
groups and recursive calls inside the pattern.

I've found the bottleneck with Intel VTune and after my optimizations which
basically consists replacing the 2 for loops inside regcppush and regccpop
with memcpy - I got about 2x faster times with my application.

Please take a look at my pull request whenever you have time - I thought I
broke the tests last time but it turned out I was only missing the one
about adding myself as an author.


Pull-request: https://github.com/Perl/perl5/pull/19814

Github issue: https://github.com/Perl/perl5/issues/19815


Thanks for your attention,

Alexander Nikolov

• Regexec optimizations - recursive patterns by sasho648