Move ArrayRef to runtime/base
Will be used in upcoming CLs regarding VDEX and VerifierDeps.
Test: m test-art-host
Change-Id: I68e611a4a52246c2bdf45eab7c61f3212908afd4
diff --git a/runtime/base/array_ref.h b/runtime/base/array_ref.h
new file mode 100644
index 0000000..00b9bad
--- /dev/null
+++ b/runtime/base/array_ref.h
@@ -0,0 +1,200 @@
+/*
+ * 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:
+ 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>
+ 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_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_; }
+
+ 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_