upload android base code part3

android/art/runtime/base/array_ref.h

@@ -0,0 +1,203 @@
+/*
+ * 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_RUNTIME_BASE_ARRAY_REF_H_
+#define ART_RUNTIME_BASE_ARRAY_REF_H_
+
+#include <type_traits>
+#include <vector>
+
+#include "base/logging.h"
+
+namespace art {
+
+/**
+ * @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:
+  using value_type = T;
+  using reference = T&;
+  using const_reference = const T&;
+  using pointer = T*;
+  using const_pointer = const T*;
+  using iterator = T*;
+  using const_iterator = const T*;
+  using reverse_iterator = std::reverse_iterator<iterator>;
+  using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+  using difference_type = ptrdiff_t;
+  using size_type = size_t;
+
+  // Constructors.
+
+  constexpr ArrayRef()
+      : array_(nullptr), size_(0u) {
+  }
+
+  template <size_t size>
+  explicit constexpr ArrayRef(T (&array)[size])
+      : array_(array), size_(size) {
+  }
+
+  template <typename U,
+            size_t size,
+            typename = typename std::enable_if<std::is_same<T, const U>::value>::type>
+  explicit constexpr ArrayRef(U (&array)[size])
+      : array_(array), size_(size) {
+  }
+
+  constexpr ArrayRef(T* array_in, size_t size_in)
+      : array_(array_in), size_(size_in) {
+  }
+
+  template <typename Vector,
+            typename = typename std::enable_if<
+                std::is_same<typename Vector::value_type, value_type>::value>::type>
+  explicit ArrayRef(Vector& v)
+      : array_(v.data()), size_(v.size()) {
+  }
+
+  template <typename Vector,
+            typename = typename std::enable_if<
+                std::is_same<
+                    typename std::add_const<typename Vector::value_type>::type,
+                    value_type>::value>::type>
+  explicit ArrayRef(const Vector& v)
+      : array_(v.data()), size_(v.size()) {
+  }
+
+  ArrayRef(const ArrayRef&) = default;
+
+  // Assignment operators.
+
+  ArrayRef& operator=(const ArrayRef& other) {
+    array_ = other.array_;
+    size_ = other.size_;
+    return *this;
+  }
+
+  template <typename U>
+  typename std::enable_if<std::is_same<T, const U>::value, ArrayRef>::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(!empty());
+    return array_[0];
+  }
+
+  const_reference front() const {
+    DCHECK(!empty());
+    return array_[0];
+  }
+
+  reference back() {
+    DCHECK(!empty());
+    return array_[size_ - 1u];
+  }
+
+  const_reference back() const {
+    DCHECK(!empty());
+    return array_[size_ - 1u];
+  }
+
+  value_type* data() { return array_; }
+  const value_type* data() const { return array_; }
+
+  ArrayRef SubArray(size_type pos) {
+    return SubArray(pos, size() - pos);
+  }
+
+  ArrayRef<const T> SubArray(size_type pos) const {
+    return SubArray(pos, size() - pos);
+  }
+
+  ArrayRef SubArray(size_type pos, size_type length) {
+    DCHECK_LE(pos, size());
+    DCHECK_LE(length, size() - pos);
+    return ArrayRef(data() + pos, length);
+  }
+
+  ArrayRef<const T> SubArray(size_type pos, size_type length) const {
+    DCHECK_LE(pos, size());
+    DCHECK_LE(length, size() - pos);
+    return ArrayRef<const T>(data() + pos, length);
+  }
+
+ private:
+  T* array_;
+  size_t size_;
+};
+
+template <typename T>
+bool operator==(const ArrayRef<T>& lhs, const ArrayRef<T>& rhs) {
+  return lhs.size() == rhs.size() && std::equal(lhs.begin(), lhs.end(), rhs.begin());
+}
+
+template <typename T>
+bool operator!=(const ArrayRef<T>& lhs, const ArrayRef<T>& rhs) {
+  return !(lhs == rhs);
+}
+
+}  // namespace art
+
+
+#endif  // ART_RUNTIME_BASE_ARRAY_REF_H_