Revert "Revert "Combine direct_methods_ and virtual_methods_ fields of mirror::Class""
This reverts commit ae358c1d5cef227b44d6f4971b79e1ab91aa26eb.
Bug: 24618811
Change-Id: I8becf9bae3258450b90cfef5e79589db7c535a4d
diff --git a/runtime/base/array_slice.h b/runtime/base/array_slice.h
new file mode 100644
index 0000000..19ad302
--- /dev/null
+++ b/runtime/base/array_slice.h
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2015 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_SLICE_H_
+#define ART_RUNTIME_BASE_ARRAY_SLICE_H_
+
+#include "length_prefixed_array.h"
+#include "stride_iterator.h"
+#include "base/bit_utils.h"
+#include "base/casts.h"
+#include "base/iteration_range.h"
+
+namespace art {
+
+// An ArraySlice is an abstraction over an array or a part of an array of a particular type. It does
+// bounds checking and can be made from several common array-like structures in Art.
+template<typename T>
+class ArraySlice {
+ public:
+ // Create an empty array slice.
+ ArraySlice() : array_(nullptr), size_(0), element_size_(0) {}
+
+ // Create an array slice of the first 'length' elements of the array, with each element being
+ // element_size bytes long.
+ ArraySlice(T* array,
+ size_t length,
+ size_t element_size = sizeof(T))
+ : array_(array),
+ size_(dchecked_integral_cast<uint32_t>(length)),
+ element_size_(element_size) {
+ DCHECK(array_ != nullptr || length == 0);
+ }
+
+ // Create an array slice of the elements between start_offset and end_offset of the array with
+ // each element being element_size bytes long. Both start_offset and end_offset are in
+ // element_size units.
+ ArraySlice(T* array,
+ uint32_t start_offset,
+ uint32_t end_offset,
+ size_t element_size = sizeof(T))
+ : array_(nullptr),
+ size_(end_offset - start_offset),
+ element_size_(element_size) {
+ DCHECK(array_ != nullptr || size_ == 0);
+ DCHECK_LE(start_offset, end_offset);
+ if (size_ != 0) {
+ uintptr_t offset = start_offset * element_size_;
+ array_ = *reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(array) + offset);
+ }
+ }
+
+ // Create an array slice of the elements between start_offset and end_offset of the array with
+ // each element being element_size bytes long and having the given alignment. Both start_offset
+ // and end_offset are in element_size units.
+ ArraySlice(LengthPrefixedArray<T>* array,
+ uint32_t start_offset,
+ uint32_t end_offset,
+ size_t element_size = sizeof(T),
+ size_t alignment = alignof(T))
+ : array_(nullptr),
+ size_(end_offset - start_offset),
+ element_size_(element_size) {
+ DCHECK(array != nullptr || size_ == 0);
+ if (size_ != 0) {
+ DCHECK_LE(start_offset, end_offset);
+ DCHECK_LE(start_offset, array->size());
+ DCHECK_LE(end_offset, array->size());
+ array_ = &array->At(start_offset, element_size_, alignment);
+ }
+ }
+
+ T& At(size_t index) {
+ DCHECK_LT(index, size_);
+ return AtUnchecked(index);
+ }
+
+ const T& At(size_t index) const {
+ DCHECK_LT(index, size_);
+ return AtUnchecked(index);
+ }
+
+ T& operator[](size_t index) {
+ return At(index);
+ }
+
+ const T& operator[](size_t index) const {
+ return At(index);
+ }
+
+ StrideIterator<T> begin() {
+ return StrideIterator<T>(&AtUnchecked(0), element_size_);
+ }
+
+ StrideIterator<const T> begin() const {
+ return StrideIterator<const T>(&AtUnchecked(0), element_size_);
+ }
+
+ StrideIterator<T> end() {
+ return StrideIterator<T>(&AtUnchecked(size_), element_size_);
+ }
+
+ StrideIterator<const T> end() const {
+ return StrideIterator<const T>(&AtUnchecked(size_), element_size_);
+ }
+
+ IterationRange<StrideIterator<T>> AsRange() {
+ return size() != 0 ? MakeIterationRange(begin(), end())
+ : MakeEmptyIterationRange(StrideIterator<T>(nullptr, 0));
+ }
+
+ size_t size() const {
+ return size_;
+ }
+
+ size_t ElementSize() const {
+ return element_size_;
+ }
+
+ private:
+ T& AtUnchecked(size_t index) {
+ return *reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(array_) + index * element_size_);
+ }
+
+ const T& AtUnchecked(size_t index) const {
+ return *reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(array_) + index * element_size_);
+ }
+
+ T* array_;
+ size_t size_;
+ size_t element_size_;
+};
+
+} // namespace art
+
+#endif // ART_RUNTIME_BASE_ARRAY_SLICE_H_