Making the loop combinator fast !

[Remi Forax]

One idea i've got during the JVM Summit,
here is a code that implements the Stream.filter/map/reduce operations using the new loop method handle,
  https://gist.github.com/forax/b5257dfac85e74335e02b5a6b95c9182

Currently, the code that use method handles is far slower than the java.util.stream.Stream equivalent,
so the challenge is how to make it perform better.

Maybe, it means we should introduce a special method handle combiner/something else that explicit ask for compiling to bytecode + JITing a method handle.

cheers,
Rémi