RFR: 8306833: Change CardTable::_covered to static array [v3]

[Kim Barrett]

On Tue, 25 Apr 2023 14:16:14 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

>> Simple refactoring to remove unused declaration in `vmStructs_gc.hpp`, which then enables more cleanup in `CardTable`.
>> 
>> Test: hotspot_gc
>
> Albert Mingkun Yang has updated the pull request incrementally with one additional commit since the last revision:
> 
>   review

Changes requested by kbarrett (Reviewer).

src/hotspot/share/gc/shared/cardTableBarrierSet.hpp line 65:

> 63:   ~CardTableBarrierSet();
> 64: 
> 65: public:

The destructor should remain public - this class is directly instantiated.
It should also be virtual, since this class is also used as a base class.  This is a small but typical example
of why classes shouldn't do such double duty.

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PR Review: https://git.openjdk.org/jdk/pull/13636#pullrequestreview-1401100561
PR Review Comment: https://git.openjdk.org/jdk/pull/13636#discussion_r1177299711