--- /dev/null	2018-04-03 12:55:20.301839954 +0200
+++ new/src/hotspot/share/gc/z/zReferenceProcessor.hpp	2018-06-06 00:42:17.663727787 +0200
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#ifndef SHARE_GC_Z_ZREFERENCEPROCESSOR_HPP
+#define SHARE_GC_Z_ZREFERENCEPROCESSOR_HPP
+
+#include "gc/shared/referenceDiscoverer.hpp"
+#include "gc/z/zValue.hpp"
+
+class ReferencePolicy;
+class ZWorkers;
+
+class ZReferenceProcessor : public ReferenceDiscoverer {
+  friend class ZReferenceProcessorTask;
+
+private:
+  static const size_t reference_type_count = REF_PHANTOM + 1;
+  typedef size_t Counters[reference_type_count];
+
+  ZWorkers* const      _workers;
+  ReferencePolicy*     _soft_reference_policy;
+  ZPerWorker<Counters> _encountered_count;
+  ZPerWorker<Counters> _discovered_count;
+  ZPerWorker<Counters> _enqueued_count;
+  ZPerWorker<oop>      _discovered_list;
+  ZContended<oop>      _pending_list;
+  oop*                 _pending_list_tail;
+
+  void update_soft_reference_clock() const;
+
+  ReferenceType reference_type(oop obj) const;
+  const char* reference_type_name(ReferenceType type) const;
+  volatile oop* reference_referent_addr(oop obj) const;
+  oop reference_referent(oop obj) const;
+  bool is_reference_inactive(oop obj) const;
+  bool is_referent_alive_or_null(oop obj, ReferenceType type) const;
+  bool is_referent_softly_alive(oop obj, ReferenceType type) const;
+  bool should_drop_reference(oop obj, ReferenceType type) const;
+  bool should_mark_referent(ReferenceType type) const;
+  bool should_clear_referent(ReferenceType type) const;
+  void keep_referent_alive(oop obj, ReferenceType type) const;
+
+  void discover(oop obj, ReferenceType type);
+  oop drop(oop obj, ReferenceType type);
+  oop* keep(oop obj, ReferenceType type);
+
+  bool is_empty() const;
+
+  void work();
+  void collect_statistics();
+
+public:
+  ZReferenceProcessor(ZWorkers* workers);
+
+  void set_soft_reference_policy(bool clear);
+  void reset_statistics();
+
+  virtual bool discover_reference(oop reference, ReferenceType type);
+  void process_references();
+  void enqueue_references();
+};
+
+#endif // SHARE_GC_Z_ZREFERENCEPROCESSOR_HPP