/* * Copyright (C) 2018 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 FRAMEWORKS_ML_NN_INDEXED_SHAPE_WRAPPER_H #define FRAMEWORKS_ML_NN_INDEXED_SHAPE_WRAPPER_H #include "OperationsUtils.h" namespace android { namespace nn { // A wrapper over a Shape class implementing some indexing logic for a wrapped // shape. // To get an offset for an element in a tensor from vector index, one needs to // calculate strides first. This class removes the need to recalculate strides // for every indexing and also provides some utility functions. class IndexedShapeWrapper { public: IndexedShapeWrapper(const Shape& wrapped_shape); // Calculates the next index in a lexicograpical order for a wrapped shape // inplace. Only accepts valid index for a given shape as an input. // Sets lastIndex to true if the received index was the last in a // lexicographical order for a given shape. In this case, index stays the // same. bool nextIndexInplace(std::vector<uint32_t>* index, bool* lastIndex) const; // Given an index as a vector with per-dimension indices, calculates an // offset of the element in a flattened tensor. bool indexToFlatIndex(const std::vector<uint32_t>& index, uint32_t* flatIndex) const; // Same as indexToFlatIndex, only ignores first dimensions of an index if // they are not present in the shape. Also ignores dimensions of a shape of // size 1. // For example: // for shape: [3, 1, 2] // and index: [4, 2, 5, 1] // the function will ignore dimensions with indices 4 and 5 and set // flatIndex to 5 as a result. bool broadcastedIndexToFlatIndex(const std::vector<uint32_t>& index, uint32_t* flatIndex) const; private: const Shape* const shape; std::vector<uint32_t> strides; bool isValid(const std::vector<uint32_t>& index) const; }; } // namespace nn } // namespace android #endif // FRAMEWORKS_ML_NN_INDEXED_SHAPE_WRAPPER_H