Java JIT loop unrolling policy?

Question

What is the loop unrolling policy for JIT? Or if there is no simple answer to that, then is there some way i can check where/when loop unrolling is being performed in a loop

Answer 1

If the JVM unrolls the loop is probably best answered by actually printing the generated assembly. Note that this requires your code to actually be executed as a hot spot (i.e. the JVM considers it worthy of the expensive optimizations).

Why the JVM decides one way or another is a much harder question and probably requires in-depth analysis of the JIT code.