--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/collectionSetChooser.hpp	Thu Jun 05 15:57:56 2008 -0700
@@ -0,0 +1,138 @@
+/*
+ * Copyright 2001-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+// We need to sort heap regions by collection desirability.
+
+class CSetChooserCache {
+private:
+  enum {
+    CacheLength = 16
+  } PrivateConstants;
+
+  HeapRegion*  _cache[CacheLength];
+  int          _occupancy; // number of region in cache
+  int          _first; // "first" region in the cache
+
+  // adding CacheLength to deal with negative values
+  inline int trim_index(int index) {
+    return (index + CacheLength) % CacheLength;
+  }
+
+  inline int get_sort_index(int index) {
+    return -index-2;
+  }
+  inline int get_index(int sort_index) {
+    return -sort_index-2;
+  }
+
+public:
+  CSetChooserCache(void);
+
+  inline int occupancy(void) { return _occupancy; }
+  inline bool is_full()      { return _occupancy == CacheLength; }
+  inline bool is_empty()     { return _occupancy == 0; }
+
+  void clear(void);
+  void insert(HeapRegion *hr);
+  HeapRegion *remove_first(void);
+  void remove (HeapRegion *hr);
+  inline HeapRegion *get_first(void) {
+    return _cache[_first];
+  }
+
+#ifndef PRODUCT
+  bool verify (void);
+  bool region_in_cache(HeapRegion *hr) {
+    int sort_index = hr->sort_index();
+    if (sort_index < -1) {
+      int index = get_index(sort_index);
+      guarantee(index < CacheLength, "should be within bounds");
+      return _cache[index] == hr;
+    } else
+      return 0;
+  }
+#endif // PRODUCT
+};
+
+class CollectionSetChooser: public CHeapObj {
+
+  GrowableArray<HeapRegion*> _markedRegions;
+  int _curMarkedIndex;
+  int _numMarkedRegions;
+  CSetChooserCache _cache;
+
+  // True iff last collection pause ran of out new "age 0" regions, and
+  // returned an "age 1" region.
+  bool _unmarked_age_1_returned_as_new;
+
+  jint _first_par_unreserved_idx;
+
+public:
+
+  HeapRegion* getNextMarkedRegion(double time_so_far, double avg_prediction);
+
+  CollectionSetChooser();
+
+  void printSortedHeapRegions();
+
+  void sortMarkedHeapRegions();
+  void fillCache();
+  bool addRegionToCache(void);
+  void addMarkedHeapRegion(HeapRegion *hr);
+
+  // Must be called before calls to getParMarkedHeapRegionChunk.
+  // "n_regions" is the number of regions, "chunkSize" the chunk size.
+  void prepareForAddMarkedHeapRegionsPar(size_t n_regions, size_t chunkSize);
+  // Returns the first index in a contiguous chunk of "n_regions" indexes
+  // that the calling thread has reserved.  These must be set by the
+  // calling thread using "setMarkedHeapRegion" (to NULL if necessary).
+  jint getParMarkedHeapRegionChunk(jint n_regions);
+  // Set the marked array entry at index to hr.  Careful to claim the index
+  // first if in parallel.
+  void setMarkedHeapRegion(jint index, HeapRegion* hr);
+  // Atomically increment the number of claimed regions by "inc_by".
+  void incNumMarkedHeapRegions(jint inc_by);
+
+  void clearMarkedHeapRegions();
+
+  void updateAfterFullCollection();
+
+  // Ensure that "hr" is not a member of the marked region array or the cache
+  void removeRegion(HeapRegion* hr);
+
+  bool unmarked_age_1_returned_as_new() { return _unmarked_age_1_returned_as_new; }
+
+  // Returns true if the used portion of "_markedRegions" is properly
+  // sorted, otherwise asserts false.
+#ifndef PRODUCT
+  bool verify(void);
+  bool regionProperlyOrdered(HeapRegion* r) {
+    int si = r->sort_index();
+    return (si == -1) ||
+      (si > -1 && _markedRegions.at(si) == r) ||
+      (si < -1 && _cache.region_in_cache(r));
+  }
+#endif
+
+};