[16] RFR(XS): 8252037: Optimized build is broken

[Vladimir Ivanov]

> I think the changes to parallelgc are contrary to the intent of the optimized build [1].  I think the
> bug here is that these counters are being conditionally printed under PRODUCT, but should
> be printed under ASSERT.  That is, 8232686 wasn’t quite right.  I guess nobody has done an
> optimized build in a while.
> 
> [1] Quoting myself from a different recent review thread:
> The purpose of "optimized" builds (as explained to me by one of its
> long-time proponents) is to have the performance characteristics of a
> release build (so no extra checks that affect performance or timing),
> but provide additional tools and data (printers, names, &etc) that we
> want to exclude from a release build for reasons of saving space or
> whatever. There's certainly lots of confusion around it though.

Ultimately it's GC team call, but counters are extensively used in 
optimized build. It this respect, it's perfectly fine to expose 
add_obj_count and add_obj_bytes in optimized build.

Best regards,
Vladimir Ivanov