RFR (S) 8250589: Move Universe::_reference_pending_list into OopHandle

[coleen.phillimore at oracle.com]

On 7/27/20 1:08 PM, Kim Barrett wrote:
>> On Jul 27, 2020, at 10:10 AM, coleen.phillimore at oracle.com wrote:
>> On 7/27/20 9:21 AM, Aleksey Shipilev wrote:
>>> On 7/27/20 3:05 PM, coleen.phillimore at oracle.com wrote:
>>> *) The change below implicitly tests for NULL now? Seems like _reference_pending_list.peek() would
>>> be more efficient here, as it would not ask GC to keep the oop alive (especially when it is
>>> guaranteed to be already alive, right?).
>>>
>>>   bool Universe::has_reference_pending_list() {
>>>     assert_pll_ownership();
>>> -  return _reference_pending_list != NULL;
>>> +  return _reference_pending_list.resolve();
>>>   }
>>>
>> This can be peek().  I'll change it.
> HotSpot Style Guide says not to use implicit conversions to bool.
> The “!= NULL” was intentional and should be retained.
>
Yes, thanks for catching that.
Coleen