On my 4-year-old Macbook Pro PHP 7.1 parses a 19Mb log file with the regex "\b\w{15}\b" 5 times faster than Python and Ruby. It's even 3 times faster than Perl which is hard to believe given Perl's insanely fast startup time.
Regex engine for all of those languages are coded in C, so that's probably not a good benchmark. That said CPython and Ruby MRI are slower than PHP5, so yeah PHP7 should be even faster.