--- /dev/null	2020-02-06 11:34:07.664987501 +0100
+++ new/src/hotspot/share/gc/shenandoah/shenandoahClosures.hpp	2020-02-06 19:19:32.663542515 +0100
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2019, 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_GC_SHENANDOAH_SHENANDOAHCLOSURES_HPP
+#define SHARE_GC_SHENANDOAH_SHENANDOAHCLOSURES_HPP
+
+#include "memory/iterator.hpp"
+
+class ShenandoahHeap;
+class ShenandoahMarkingContext;
+class Thread;
+
+class ShenandoahForwardedIsAliveClosure: public BoolObjectClosure {
+private:
+  ShenandoahMarkingContext* const _mark_context;
+public:
+  inline ShenandoahForwardedIsAliveClosure();
+  inline bool do_object_b(oop obj);
+};
+
+class ShenandoahIsAliveClosure: public BoolObjectClosure {
+private:
+  ShenandoahMarkingContext* const _mark_context;
+public:
+  inline ShenandoahIsAliveClosure();
+  inline bool do_object_b(oop obj);
+};
+
+class ShenandoahIsAliveSelector : public StackObj {
+private:
+  ShenandoahIsAliveClosure _alive_cl;
+  ShenandoahForwardedIsAliveClosure _fwd_alive_cl;
+public:
+  inline BoolObjectClosure* is_alive_closure();
+};
+
+class ShenandoahUpdateRefsClosure: public OopClosure {
+private:
+  ShenandoahHeap* _heap;
+public:
+  inline ShenandoahUpdateRefsClosure();
+  inline void do_oop(oop* p);
+  inline void do_oop(narrowOop* p);
+private:
+  template <class T>
+  inline void do_oop_work(T* p);
+};
+
+class ShenandoahEvacuateUpdateRootsClosure: public BasicOopIterateClosure {
+private:
+  ShenandoahHeap* _heap;
+  Thread* _thread;
+public:
+  inline ShenandoahEvacuateUpdateRootsClosure();
+  inline void do_oop(oop* p);
+  inline void do_oop(narrowOop* p);
+
+private:
+  template <class T>
+  inline void do_oop_work(T* p);
+};
+
+#ifdef ASSERT
+class ShenandoahAssertNotForwardedClosure : public OopClosure {
+private:
+  template <class T>
+  inline void do_oop_work(T* p);
+
+public:
+  inline void do_oop(narrowOop* p);
+  inline void do_oop(oop* p);
+};
+#endif // ASSERT
+
+#endif // SHARE_GC_SHENANDOAH_SHENANDOAHCLOSURES_HPP