| // Copyright 2016 Google Inc. All Rights Reserved. |
| // |
| // 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. |
| |
| // iterator.h: Const forward iterators for VectorMap and VectorDup that help |
| // access data in architecture specific way, e.g. 4 elements at a time for NEON. |
| |
| #ifndef GEMMLOWP_INTERNAL_ITERATOR_H_ |
| #define GEMMLOWP_INTERNAL_ITERATOR_H_ |
| |
| namespace gemmlowp { |
| |
| enum class VectorShape; |
| |
| // ConstIterator is a forward only constant iterator that can be made |
| // architecture specific e.g. to return 4 values at once for NEON. |
| template <typename VectorType> class ConstIterator { |
| // Unused default case. |
| }; |
| |
| template <typename tScalar, VectorShape tShape> class VectorMap; |
| |
| template <typename tScalar, VectorShape tShape> |
| class ConstIterator<VectorMap<tScalar, tShape>> { |
| public: |
| typedef tScalar Scalar; |
| ConstIterator(const VectorMap<tScalar, tShape>& vector_map) |
| : pointer_(vector_map.data()) {} |
| const Scalar operator*() const { return *pointer_; } |
| const Scalar* get() const { return pointer_; } |
| ConstIterator& operator+=(int inc) { pointer_ += inc; return *this; } |
| private: |
| const Scalar* pointer_; |
| }; |
| |
| template <typename tScalar, VectorShape tShape> |
| ConstIterator<VectorMap<tScalar, tShape>> const_iterator( |
| const VectorMap<tScalar, tShape>& vector_map) { |
| return ConstIterator<VectorMap<tScalar, tShape>>(vector_map); |
| } |
| |
| template <typename tScalar, VectorShape tShape> class VectorDup; |
| |
| template <typename tScalar, VectorShape tShape> |
| class ConstIterator<VectorDup<tScalar, tShape>> { |
| public: |
| typedef tScalar Scalar; |
| ConstIterator(const VectorDup<tScalar, tShape>& vector_dup) |
| : data_(vector_dup(0)) {} |
| const Scalar operator*() const { return data_; } |
| const Scalar* get() const { return &data_; } |
| ConstIterator& operator+=(int inc) { return *this; } |
| private: |
| Scalar data_; |
| }; |
| |
| template <typename tScalar, VectorShape tShape> |
| ConstIterator<VectorDup<tScalar, tShape>> const_iterator( |
| const VectorDup<tScalar, tShape>& vector_map) { |
| return ConstIterator<VectorDup<tScalar, tShape>>(vector_map); |
| } |
| |
| } // namespace gemmlowp |
| |
| #endif // GEMMLOWP_INTERNAL_ITERATOR_H_ |