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diff --git a/compiler/utils/array_ref.h b/compiler/utils/array_ref.h
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+/*
+ * Copyright (C) 2014 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_ARRAY_REF_H_
+#define ART_COMPILER_UTILS_ARRAY_REF_H_
+
+#include <type_traits>
+#include <vector>
+
+#include "base/logging.h"
+
+namespace art {
+
+template <typename T, bool ok> struct ArrayRefHelper;
+
+/**
+ * @brief A container that references an array.
+ *
+ * @details The template class ArrayRef provides a container that references
+ * an external array. This external array must remain alive while the ArrayRef
+ * object is in use. The external array may be a std::vector<>-backed storage
+ * or any other contiguous chunk of memory but that memory must remain valid,
+ * i.e. the std::vector<> must not be resized for example.
+ *
+ * Except for copy/assign and insert/erase/capacity functions, the interface
+ * is essentially the same as std::vector<>. Since we don't want to throw
+ * exceptions, at() is also excluded.
+ */
+template <typename T>
+class ArrayRef {
+ public:
+  typedef T value_type;
+  typedef T& reference;
+  typedef const T& const_reference;
+  typedef T* pointer;
+  typedef const T* const_pointer;
+  typedef T* iterator;
+  typedef const T* const_iterator;
+  typedef std::reverse_iterator<iterator> reverse_iterator;
+  typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+  typedef ptrdiff_t difference_type;
+  typedef size_t size_type;
+
+  // Constructors.
+
+  constexpr ArrayRef()
+      : array_(nullptr), size_(0u) {
+  }
+
+  template <size_t size>
+  constexpr ArrayRef(T (&array)[size])
+    : array_(array), size_(size) {
+  }
+
+  template <typename U, size_t size>
+  constexpr ArrayRef(U (&array)[size],
+                     typename ArrayRefHelper<T, std::is_same<T, const U>::value>::tag t = tag())
+    : array_(array), size_(size) {
+  }
+
+  constexpr ArrayRef(T* array, size_t size)
+      : array_(array), size_(size) {
+  }
+
+  template <typename U>
+  constexpr ArrayRef(U* array, size_t size,
+                     typename ArrayRefHelper<T, std::is_same<T, const U>::value>::tag t = tag())
+      : array_(array), size_(size) {
+  }
+
+  explicit ArrayRef(std::vector<T>& v)
+      : array_(v.data()), size_(v.size()) {
+  }
+
+  template <typename U>
+  ArrayRef(const std::vector<U>& v,
+           typename ArrayRefHelper<T, std::is_same<T, const U>::value>::tag t = tag())
+      : array_(v.data()), size_(v.size()) {
+  }
+
+  // Assignment operators.
+
+  ArrayRef& operator=(const ArrayRef& other) {
+    array_ = other.array_;
+    size_ = other.size_;
+    return *this;
+  }
+
+  template <typename U>
+  typename ArrayRefHelper<T, std::is_same<T, const U>::value>::type&
+  operator=(const ArrayRef<U>& other) {
+    return *this = ArrayRef(other);
+  }
+
+  // Destructor.
+  ~ArrayRef() = default;
+
+  // Iterators.
+  iterator begin() { return array_; }
+  const_iterator begin() const { return array_; }
+  const_iterator cbegin() const { return array_; }
+  iterator end() { return array_ + size_; }
+  const_iterator end() const { return array_ + size_; }
+  const_iterator cend() const { return array_ + size_; }
+  reverse_iterator rbegin() { return reverse_iterator(end()); }
+  const_reverse_iterator rbegin() const { return const_reverse_iterator(end()); }
+  const_reverse_iterator crbegin() const { return const_reverse_iterator(cend()); }
+  reverse_iterator rend() { return reverse_iterator(begin()); }
+  const_reverse_iterator rend() const { return const_reverse_iterator(begin()); }
+  const_reverse_iterator crend() const { return const_reverse_iterator(cbegin()); }
+
+  // Size.
+  size_type size() const { return size_; }
+  bool empty() const { return size() == 0u; }
+
+  // Element access. NOTE: Not providing at().
+
+  reference operator[](size_type n) {
+    DCHECK_LT(n, size_);
+    return array_[n];
+  }
+
+  const_reference operator[](size_type n) const {
+    DCHECK_LT(n, size_);
+    return array_[n];
+  }
+
+  reference front() {
+    DCHECK_NE(size_, 0u);
+    return array_[0];
+  }
+
+  const_reference front() const {
+    DCHECK_NE(size_, 0u);
+    return array_[0];
+  }
+
+  reference back() {
+    DCHECK_NE(size_, 0u);
+    return array_[size_ - 1u];
+  }
+
+  const_reference back() const {
+    DCHECK_NE(size_, 0u);
+    return array_[size_ - 1u];
+  }
+
+  value_type* data() { return array_; }
+  const value_type* data() const { return array_; }
+
+ private:
+  struct tag { };
+  friend struct ArrayRefHelper<T, true>;
+
+  T* array_;
+  size_t size_;
+};
+
+template <typename T> struct ArrayRefHelper<T, true> {
+  typedef typename ArrayRef<T>::tag tag;
+  typedef ArrayRef<T> type;
+};
+
+template <typename T> struct ArrayRefHelper<T, false> {
+  // SFINAE: No "tag" or "type" typedef.
+};
+
+}  // namespace art
+
+
+#endif  // ART_COMPILER_UTILS_ARRAY_REF_H_