Faster Array#/MutableArray# copies

[Roman Leshchinskiy]

Johan Tibell wrote:
>
> * Could we use built-in compiler rules to catch array copies of known
> length and replace them with e.g. unrolled loops? My particular use case
> involves copying small arrays (size: 1-32). Ideally this should be as fast
> as copying a tuple of the corresponding size but I'm pretty sure we're far
> off that goal.

Out of idle curiousity, couldn't you use tuples instead of arrays?

FWIW, I agree that doing something cleverer than just calling memcpy could
be very worthwhile. As Max points out, you could perhaps try to do
something with the LLVM backend.

Roman