8198515: Extract SoftReferencePolicy code out of CollectorPolicy
Reviewed-by: pliden, sjohanss
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP
#define SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP
#include "gc/serial/defNewGeneration.hpp"
#include "gc/shared/cardTableRS.hpp"
#include "gc/shared/genCollectedHeap.hpp"
#include "gc/shared/genOopClosures.inline.hpp"
#include "gc/shared/space.hpp"
// Methods of protected closure types
template <class T>
inline void DefNewGeneration::KeepAliveClosure::do_oop_work(T* p) {
#ifdef ASSERT
{
// We never expect to see a null reference being processed
// as a weak reference.
assert (!oopDesc::is_null(*p), "expected non-null ref");
oop obj = oopDesc::load_decode_heap_oop_not_null(p);
assert (oopDesc::is_oop(obj), "expected an oop while scanning weak refs");
}
#endif // ASSERT
_cl->do_oop_nv(p);
// Card marking is trickier for weak refs.
// This oop is a 'next' field which was filled in while we
// were discovering weak references. While we might not need
// to take a special action to keep this reference alive, we
// will need to dirty a card as the field was modified.
//
// Alternatively, we could create a method which iterates through
// each generation, allowing them in turn to examine the modified
// field.
//
// We could check that p is also in the old generation, but
// dirty cards in the young gen are never scanned, so the
// extra check probably isn't worthwhile.
if (GenCollectedHeap::heap()->is_in_reserved(p)) {
oop obj = oopDesc::load_decode_heap_oop_not_null(p);
_rs->inline_write_ref_field_gc(p, obj);
}
}
template <class T>
inline void DefNewGeneration::FastKeepAliveClosure::do_oop_work(T* p) {
#ifdef ASSERT
{
// We never expect to see a null reference being processed
// as a weak reference.
assert (!oopDesc::is_null(*p), "expected non-null ref");
oop obj = oopDesc::load_decode_heap_oop_not_null(p);
assert (oopDesc::is_oop(obj), "expected an oop while scanning weak refs");
}
#endif // ASSERT
_cl->do_oop_nv(p);
// Optimized for Defnew generation if it's the youngest generation:
// we set a younger_gen card if we have an older->youngest
// generation pointer.
oop obj = oopDesc::load_decode_heap_oop_not_null(p);
if (((HeapWord*)obj < _boundary) && GenCollectedHeap::heap()->is_in_reserved(p)) {
_rs->inline_write_ref_field_gc(p, obj);
}
}
#endif // SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP