--- /dev/null	2018-11-30 10:10:44.238550338 +0100
+++ new/src/hotspot/share/gc/shenandoah/shenandoahMarkCompact.hpp	2018-11-30 21:08:12.540336845 +0100
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2014, 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_SHENANDOAHMARKCOMPACT_HPP
+#define SHARE_VM_GC_SHENANDOAH_SHENANDOAHMARKCOMPACT_HPP
+
+#include "gc/shared/gcTimer.hpp"
+#include "gc/shenandoah/shenandoahHeap.hpp"
+#include "gc/shenandoah/shenandoahHeapRegionSet.hpp"
+
+/**
+ * This implements Full GC (e.g. when invoking System.gc()) using a mark-compact algorithm.
+ *
+ * Current implementation is parallel sliding Lisp-2-style algorithm, based on
+ * "Parallel Garbage Collection for Shared Memory Multiprocessors", by Christine Flood et al.
+ * http://people.csail.mit.edu/shanir/publications/dfsz2001.pdf
+ *
+ * It is implemented in four phases:
+ *
+ * 1. Mark all live objects of the heap by traversing objects starting at GC roots.
+ * 2. Calculate the new location of each live object. This is done by sequentially scanning
+ *    the heap, keeping track of a next-location-pointer, which is then written to each
+ *    object's fwdptr field.
+ * 3. Update all references. This is implemented by another scan of the heap, and updates
+ *    all references in live objects by what's stored in the target object's fwdptr.
+ * 4. Compact the heap by copying all live objects to their new location.
+ *
+ * Parallelization is handled by assigning each GC worker the slice of the heap (the set of regions)
+ * where it does sliding compaction, without interfering with other threads.
+ */
+
+class ShenandoahMarkCompact : public CHeapObj<mtGC> {
+private:
+  GCTimer* _gc_timer;
+
+public:
+  void initialize(GCTimer* gc_timer);
+  void do_it(GCCause::Cause gc_cause);
+
+private:
+  void phase1_mark_heap();
+  void phase2_calculate_target_addresses(ShenandoahHeapRegionSet** worker_slices);
+  void phase3_update_references();
+  void phase4_compact_objects(ShenandoahHeapRegionSet** worker_slices);
+
+  void calculate_target_humongous_objects();
+  void compact_humongous_objects();
+
+};
+
+#endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHMARKCOMPACT_HPP