src/hotspot/share/gc/z/zReferenceProcessor.hpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
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#ifndef SHARE_GC_Z_ZREFERENCEPROCESSOR_HPP
#define SHARE_GC_Z_ZREFERENCEPROCESSOR_HPP

#include "gc/shared/referenceDiscoverer.hpp"
#include "gc/z/zAddress.hpp"
#include "gc/z/zValue.hpp"

class ConcurrentGCTimer;
class ReferencePolicy;
class ZWorkers;

class ZReferenceProcessor : public ReferenceDiscoverer {
  friend class ZReferenceProcessorTask;

private:
  static const size_t ReferenceTypeCount = REF_PHANTOM + 1;
  typedef size_t Counters[ReferenceTypeCount];

  ZWorkers* const      _workers;
  ReferencePolicy*     _soft_reference_policy;
  bool                 _uses_clear_all_soft_reference_policy;
  ZPerWorker<Counters> _encountered_count;
  ZPerWorker<Counters> _discovered_count;
  ZPerWorker<Counters> _enqueued_count;
  ZPerWorker<zaddress> _discovered_list;
  ZContended<zaddress> _pending_list;
  zaddress             _pending_list_tail;

  bool is_inactive(zaddress reference, oop referent, ReferenceType type) const;
  bool is_strongly_live(oop referent) const;
  bool is_softly_live(zaddress reference, ReferenceType type) const;

  bool should_discover(zaddress reference, ReferenceType type) const;
  bool try_make_inactive(zaddress reference, ReferenceType type) const;

  void discover(zaddress reference, ReferenceType type);

  void verify_empty() const;

  void process_worker_discovered_list(zaddress discovered_list);
  void work();
  void collect_statistics();

  zaddress swap_pending_list(zaddress pending_list);

public:
  ZReferenceProcessor(ZWorkers* workers);

  void set_soft_reference_policy(bool clear_all_soft_references);
  bool uses_clear_all_soft_reference_policy() const;

  void reset_statistics();

  virtual bool discover_reference(oop reference, ReferenceType type);
  void process_references();
  void enqueue_references();

  void verify_pending_references();
};

#endif // SHARE_GC_Z_ZREFERENCEPROCESSOR_HPP