6906727: UseCompressedOops: some card-marking fixes related to object arrays
Summary: Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17).
Reviewed-by: kvn, coleenp, jmasa
/*
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// A klassOop is the C++ equivalent of a Java class.
// Part of a klassOopDesc is a Klass which handle the
// dispatching for the C++ method calls.
// klassOop object layout:
// [header ]
// [klass_field]
// [KLASS ]
class klassOopDesc : public oopDesc {
public:
// size operation
static int header_size() { return sizeof(klassOopDesc)/HeapWordSize; }
// support for code generation
static int klass_part_offset_in_bytes() { return sizeof(klassOopDesc); }
// returns the Klass part containing dispatching behavior
Klass* klass_part() { return (Klass*)((address)this + klass_part_offset_in_bytes()); }
};