--- /dev/null	2018-11-26 11:49:18.255023023 +0100
+++ new/src/hotspot/share/gc/shenandoah/shenandoahConcurrentMark.hpp	2018-11-26 21:28:56.579694843 +0100
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2013, 2018, Red Hat, Inc. All rights reserved.
+ *
+ * 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_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_HPP
+#define SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_HPP
+
+#include "gc/shared/taskqueue.hpp"
+#include "gc/shenandoah/shenandoahOopClosures.hpp"
+#include "gc/shenandoah/shenandoahPhaseTimings.hpp"
+#include "gc/shenandoah/shenandoahTaskqueue.hpp"
+
+class ShenandoahStrDedupQueue;
+
+class ShenandoahConcurrentMark: public CHeapObj<mtGC> {
+  friend class ShenandoahTraversalGC;
+private:
+  ShenandoahHeap* _heap;
+  ShenandoahObjToScanQueueSet* _task_queues;
+
+public:
+  void initialize(uint workers);
+  void cancel();
+
+// ---------- Marking loop and tasks
+//
+private:
+  template <class T>
+  inline void do_task(ShenandoahObjToScanQueue* q, T* cl, jushort* live_data, ShenandoahMarkTask* task);
+
+  template <class T>
+  inline void do_chunked_array_start(ShenandoahObjToScanQueue* q, T* cl, oop array);
+
+  template <class T>
+  inline void do_chunked_array(ShenandoahObjToScanQueue* q, T* cl, oop array, int chunk, int pow);
+
+  inline void count_liveness(jushort* live_data, oop obj);
+
+  template <class T, bool CANCELLABLE>
+  void mark_loop_work(T* cl, jushort* live_data, uint worker_id, ShenandoahTaskTerminator *t);
+
+  template <bool CANCELLABLE>
+  void mark_loop_prework(uint worker_id, ShenandoahTaskTerminator *terminator, ReferenceProcessor *rp, bool strdedup);
+
+public:
+  void mark_loop(uint worker_id, ShenandoahTaskTerminator* terminator, ReferenceProcessor *rp,
+                 bool cancellable, bool strdedup) {
+    if (cancellable) {
+      mark_loop_prework<true>(worker_id, terminator, rp, strdedup);
+    } else {
+      mark_loop_prework<false>(worker_id, terminator, rp, strdedup);
+    }
+  }
+
+  template<class T, UpdateRefsMode UPDATE_REFS, StringDedupMode STRING_DEDUP>
+  static inline void mark_through_ref(T* p, ShenandoahHeap* heap, ShenandoahObjToScanQueue* q, ShenandoahMarkingContext* const mark_context);
+
+  void mark_from_roots();
+  void finish_mark_from_roots(bool full_gc);
+
+  void mark_roots(ShenandoahPhaseTimings::Phase root_phase);
+  void update_roots(ShenandoahPhaseTimings::Phase root_phase);
+
+// ---------- Weak references
+//
+private:
+  void weak_refs_work(bool full_gc);
+  void weak_refs_work_doit(bool full_gc);
+
+public:
+  void preclean_weak_refs();
+
+// ---------- Concurrent code cache
+//
+private:
+  ShenandoahSharedFlag _claimed_codecache;
+
+public:
+  void concurrent_scan_code_roots(uint worker_id, ReferenceProcessor* rp);
+  bool claim_codecache();
+  void clear_claim_codecache();
+
+// ---------- Helpers
+// Used from closures, need to be public
+//
+public:
+  ShenandoahObjToScanQueue* get_queue(uint worker_id);
+  ShenandoahObjToScanQueueSet* task_queues() { return _task_queues; }
+
+};
+
+#endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_HPP