This will actually be (a little) slower, because you're going through another level of indirection. As
japhy and
TGI have already pointed out, copying a large data structure to the stack for a subroutine is often more expensive.
What you gain in this case is nothing. You're also using a few bytes more memory in your snippet than you would be using without the reference -- just not enough to count.
However, when you want to pass two arrays into a function, you'll be very glad you know how to take a reference to an array.
In general, unless you need to use them, don't.