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diff --git a/compiler/utils/dedupe_set.h b/compiler/utils/dedupe_set.h
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+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_COMPILER_UTILS_DEDUPE_SET_H_
+#define ART_COMPILER_UTILS_DEDUPE_SET_H_
+
+#include <set>
+
+#include "base/mutex.h"
+#include "base/stl_util.h"
+
+namespace art {
+
+// A simple data structure to handle hashed deduplication. Add is thread safe.
+template <typename Key, typename HashType, typename HashFunc>
+class DedupeSet {
+  typedef std::pair<HashType, Key*> HashedKey;
+
+  class Comparator {
+   public:
+    bool operator()(const HashedKey& a, const HashedKey& b) const {
+      if (a.first < b.first) return true;
+      if (a.first > b.first) return true;
+      return *a.second < *b.second;
+    }
+  };
+
+  typedef std::set<HashedKey, Comparator> Keys;
+
+ public:
+  typedef typename Keys::iterator iterator;
+  typedef typename Keys::const_iterator const_iterator;
+  typedef typename Keys::size_type size_type;
+  typedef typename Keys::value_type value_type;
+
+  iterator begin() { return keys_.begin(); }
+  const_iterator begin() const { return keys_.begin(); }
+  iterator end() { return keys_.end(); }
+  const_iterator end() const { return keys_.end(); }
+
+  Key* Add(Thread* self, const Key& key) {
+    HashType hash = HashFunc()(key);
+    HashedKey hashed_key(hash, const_cast<Key*>(&key));
+    MutexLock lock(self, lock_);
+    auto it = keys_.find(hashed_key);
+    if (it != keys_.end()) {
+      return it->second;
+    }
+    hashed_key.second = new Key(key);
+    keys_.insert(hashed_key);
+    return hashed_key.second;
+  }
+
+  DedupeSet() : lock_("dedupe lock") {
+  }
+
+  ~DedupeSet() {
+    STLDeleteValues(&keys_);
+  }
+
+ private:
+  Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
+  Keys keys_;
+  DISALLOW_COPY_AND_ASSIGN(DedupeSet);
+};
+
+}  // namespace art
+
+#endif  // ART_COMPILER_UTILS_DEDUPE_SET_H_