1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "IndexedShapeWrapper"
18 
19 #include "IndexedShapeWrapper.h"
20 
21 #include <vector>
22 
23 #include "LegacyUtils.h"
24 
25 namespace android {
26 namespace nn {
27 
IndexedShapeWrapper(const Shape & wrapped_shape)28 IndexedShapeWrapper::IndexedShapeWrapper(const Shape& wrapped_shape) : shape(&wrapped_shape) {
29     strides.resize(shape->dimensions.size());
30     strides.back() = 1;
31     for (int i = strides.size() - 2; i >= 0; --i) {
32         strides[i] = shape->dimensions[i + 1] * strides[i + 1];
33     }
34 }
35 
nextIndexInplace(std::vector<uint32_t> * index,bool * lastIndex) const36 bool IndexedShapeWrapper::nextIndexInplace(std::vector<uint32_t>* index, bool* lastIndex) const {
37     NN_CHECK(isValid(*index));
38 
39     bool anyIndicesLeft = false;
40     for (size_t i = 0; i < index->size(); ++i) {
41         if (index->at(i) < shape->dimensions[i] - 1) {
42             anyIndicesLeft = true;
43             break;
44         }
45     }
46     if (!anyIndicesLeft) {
47         *lastIndex = true;
48         return true;
49     }
50     for (int i = index->size() - 1; i >= 0; --i) {
51         ++index->at(i);
52         if (index->at(i) == shape->dimensions[i]) {
53             index->at(i) = 0;
54         } else {
55             break;
56         }
57     }
58     return true;
59 }
60 
indexToFlatIndex(const std::vector<uint32_t> & index,uint32_t * flatIndex) const61 bool IndexedShapeWrapper::indexToFlatIndex(const std::vector<uint32_t>& index,
62                                            uint32_t* flatIndex) const {
63     NN_CHECK(isValid(index));
64 
65     *flatIndex = 0;
66     for (size_t i = 0; i < index.size(); ++i) {
67         *flatIndex += strides[i] * index[i];
68     }
69     return true;
70 }
71 
broadcastedIndexToFlatIndex(const std::vector<uint32_t> & index,uint32_t * flatIndex) const72 bool IndexedShapeWrapper::broadcastedIndexToFlatIndex(const std::vector<uint32_t>& index,
73                                                       uint32_t* flatIndex) const {
74     NN_CHECK(index.size() >= strides.size());
75 
76     *flatIndex = 0;
77     for (size_t i = 1; i <= strides.size(); ++i) {
78         uint32_t currentIndex = index[index.size() - i];
79         uint32_t currentDimSize = shape->dimensions[shape->dimensions.size() - i];
80         NN_CHECK(currentIndex < currentDimSize || currentDimSize == 1);
81         if (currentDimSize != 1) {
82             *flatIndex += strides[strides.size() - i] * index[index.size() - i];
83         }
84     }
85     return true;
86 }
87 
isValid(const std::vector<uint32_t> & index) const88 bool IndexedShapeWrapper::isValid(const std::vector<uint32_t>& index) const {
89     if (index.size() != shape->dimensions.size()) {
90         LOG(ERROR) << "Index: " << toString(index)
91                    << " has a different number of dimensions from shape: "
92                    << toString(shape->dimensions);
93         return false;
94     }
95     for (size_t i = 0; i < index.size(); ++i) {
96         if (index[i] >= shape->dimensions[i]) {
97             LOG(ERROR) << "Invalid index: " << toString(index)
98                        << " is out of range for shape: " << toString(shape->dimensions);
99             return false;
100         }
101     }
102     return true;
103 }
104 
105 }  // namespace nn
106 }  // namespace android
107