RFR(M): 8244504: C2: refactor counted loop code in preparation for long counted loop

[Roland Westrelin]

Thanks reviewing this.

> addnode.hpp
> - Now that you've introduced these helper methods, shouldn't you also replace other usages (not only
> loop opts)? For example, in ModINode::Ideal

That would make sense but:

int hack_res = (i >= 0) ? divisor : 1;

is not a min, right?

I don't see any other in the C2 code base.

> loopPredicate.cpp:
> - "kind predicates" -> "kinds of predicates"
> - change in line 136 was already fixed as part of 8245714, right?

Right.

Roland.