Constrains for ArraycopySrcPrefetchDistance and ArraycopyDstPrefetchDistance XX options were added in the JDK 9 to the hotspot/src/share/vm/runtime/commandLineFlagConstraintsCompiler.cpp file.

Accoring to the added constraints the only possible value for ArraycopySrcPrefetchDistance and ArraycopyDstPrefetchDistance options is 0. All other values are rejected.

So, it seems that these options can be deprecated and removed in the future release. Also, corresponding code for these options also can be removed.

zmajo: Instead of deprecating the two options, I'll change the constraints to allow a range for the flags.