--- /dev/null	2016-05-31 09:42:47.975716356 -0700
+++ new/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.debug/src/org/graalvm/compiler/debug/internal/DebugHistogramImpl.java	2016-12-07 13:49:04.728357803 -0800
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package org.graalvm.compiler.debug.internal;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+
+import org.graalvm.compiler.debug.DebugHistogram;
+
+public class DebugHistogramImpl implements DebugHistogram {
+
+    private final String name;
+    private HashMap<Object, CountedValue> map = new HashMap<>();
+
+    public DebugHistogramImpl(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public void add(Object value) {
+        CountedValue cv = map.get(value);
+        if (cv == null) {
+            map.put(value, new CountedValue(1, value));
+        } else {
+            cv.inc();
+        }
+    }
+
+    @Override
+    public void add(Object value, long count) {
+        CountedValue cv = map.get(value);
+        if (cv == null) {
+            map.put(value, new CountedValue(count, value));
+        } else {
+            cv.add(count);
+        }
+    }
+
+    @Override
+    public String getName() {
+        return name;
+    }
+
+    @Override
+    public List<CountedValue> getValues() {
+        ArrayList<CountedValue> res = new ArrayList<>(map.values());
+        Collections.sort(res);
+        return res;
+    }
+}