--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/gc_implementation/shared/liveRange.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2001-2003 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.
+ *
+ */
+
+// This is a shared helper class used during phase 3 and 4 to move all the objects
+// Dead regions in a Space are linked together to keep track of the live regions
+// so that the live data can be traversed quickly without having to look at each
+// object.
+
+class LiveRange: public MemRegion {
+public:
+  LiveRange(HeapWord* bottom, HeapWord* top): MemRegion(bottom, top) {}
+
+  void set_end(HeapWord* e) {
+    assert(e >= start(), "should be a non-zero range");
+    MemRegion::set_end(e);
+  }
+  void set_word_size(size_t ws) {
+    assert(ws >= 0, "should be a non-zero range");
+    MemRegion::set_word_size(ws);
+  }
+
+  LiveRange * next() { return (LiveRange *) end(); }
+
+  void move_to(HeapWord* destination) {
+    Copy::aligned_conjoint_words(start(), destination, word_size());
+  }
+};