--- /dev/null	2015-10-06 23:29:51.451421828 +0200
+++ new/src/share/vm/gc/shenandoah/shenandoahHeapRegionSet.hpp	2015-10-14 13:54:52.424965617 +0200
@@ -0,0 +1,122 @@
+/*
+ * Copyright (c) 2013, 2015, Red Hat, Inc. and/or its affiliates.
+ *
+ * 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_SHENANDOAHHEAPREGIONSET_HPP
+#define SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP
+
+#include "gc/shenandoah/shenandoahHeapRegion.hpp"
+
+
+class ShenandoahHeapRegionSet : public CHeapObj<mtGC> {
+private:
+  ShenandoahHeapRegion** _regions;
+  // current region to be returned from get_next()
+  ShenandoahHeapRegion** _current;
+  ShenandoahHeapRegion** _next;
+
+  // last inserted region.
+  ShenandoahHeapRegion** _next_free;
+  ShenandoahHeapRegion** _concurrent_next_free;
+
+  // Maximum size of the set.
+  const size_t _max_regions;
+
+  size_t _garbage_threshold;
+  size_t _free_threshold;
+
+  size_t _available;
+  size_t _used;
+
+  void choose_collection_set(ShenandoahHeapRegion** regions, size_t length);
+  void choose_collection_set_min_garbage(ShenandoahHeapRegion** regions, size_t length, size_t min_garbage);
+  void choose_free_set(ShenandoahHeapRegion** regions, size_t length);
+
+public:
+  ShenandoahHeapRegionSet(size_t max_regions);
+
+  ShenandoahHeapRegionSet(size_t max_regions, ShenandoahHeapRegion** regions, size_t num_regions);
+
+  ~ShenandoahHeapRegionSet();
+
+  void set_garbage_threshold(size_t minimum_garbage) { _garbage_threshold = minimum_garbage;}
+  void set_free_threshold(size_t minimum_free) { _free_threshold = minimum_free;}
+
+  /**
+   * Appends a region to the set. This is implemented to be concurrency-safe.
+   */
+  void append(ShenandoahHeapRegion* region);
+
+  void clear();
+
+  size_t length();
+  size_t used_regions() {
+    return _current - _regions;
+  }
+  size_t available_regions();
+  void print();
+
+  size_t garbage();
+  size_t used();
+  size_t live_data();
+  size_t reclaimed() {return _reclaimed;}
+
+  /**
+   * Returns a pointer to the current region.
+   */
+   ShenandoahHeapRegion* current();
+
+  /**
+   * Gets the next region for allocation (from free-list).
+   * If multiple threads are competing, one will succeed to
+   * increment to the next region, the others will fail and return
+   * the region that the succeeding thread got.
+   */
+  ShenandoahHeapRegion* get_next();
+
+  /**
+   * Claims next region for processing. This is implemented to be concurrency-safe.
+   */
+  ShenandoahHeapRegion* claim_next();
+
+  void choose_collection_and_free_sets(ShenandoahHeapRegionSet* col_set, ShenandoahHeapRegionSet* free_set);
+  void choose_collection_and_free_sets_min_garbage(ShenandoahHeapRegionSet* col_set, ShenandoahHeapRegionSet* free_set, size_t min_garbage);
+
+  // Check for unreachable humongous regions and reclaim them.
+  void reclaim_humongous_regions();
+
+  void set_concurrent_iteration_safe_limits();
+
+  void decrease_available(size_t num_bytes);
+
+  size_t available() const;
+  size_t used() const;
+
+private:
+  void reclaim_humongous_region_at(ShenandoahHeapRegion** r);
+
+  ShenandoahHeapRegion** limit_region(ShenandoahHeapRegion** region);
+  size_t _reclaimed;
+
+};
+
+#endif //SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP