RFR: 8279856: Parallel: Use PreservedMarks to record promotion-failed objects

[Stefan Johansson]

On Tue, 11 Jan 2022 14:02:20 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Simple change of using `PreservedMarks` to skip young-gen walking in finding promotion-failed objs.
> 
> Test: tier1-6

src/hotspot/share/gc/parallel/psScavenge.cpp line 708:

> 706:   RemoveForwardedPointerClosure remove_fwd_ptr_closure;
> 707:   young_gen->object_iterate(&remove_fwd_ptr_closure);
> 708: 

Since these are removed, there is no longer any need to get `heap` and `young_gen` above either. I think the cleanest would be do directly use `ParallelScavengeHeap::heap()` in: 

NOT_PRODUCT(heap->reset_promotion_should_fail();)

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PR: https://git.openjdk.java.net/jdk/pull/7028