1/*
2 * Copyright (C) 2017 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#ifndef FRAMEWORKS_ML_NN_LSTMCELL_H
18#define FRAMEWORKS_ML_NN_LSTMCELL_H
19
20#include "ActivationFunctor.h"
21#include "tensorflow/contrib/lite/kernels/internal/tensor_utils.h"
22
23#include <algorithm>
24#include <cmath>
25
26namespace android {
27namespace hardware {
28namespace neuralnetworks {
29namespace V1_1 {
30struct Operation;
31}
32}  // namespace neuralnetworks
33}  // namespace hardware
34}  // namespace android
35
36namespace android {
37namespace nn {
38
39struct LSTMParams {
40  TfLiteFusedActivation activation_;
41  float cell_clip_;
42  float proj_clip_;
43};
44
45struct RunTimeOperandInfo;
46struct Shape;
47
48class LSTMCell {
49 public:
50  LSTMCell(const android::hardware::neuralnetworks::V1_1::Operation &operation,
51           std::vector<RunTimeOperandInfo> &operands);
52
53  static bool Prepare(const android::hardware::neuralnetworks::V1_1::Operation &operation,
54                      std::vector<RunTimeOperandInfo> &operands,
55                      Shape *scratchShape,
56                      Shape *outputStateShape,
57                      Shape *cellStateShape,
58                      Shape *outputShape);
59  bool Eval();
60
61  // Input Tensors of size {n_batch, n_input}
62  static constexpr int kInputTensor = 0;
63
64  // Input weight tensors of size: {n_cell, n_input}
65  static constexpr int kInputToInputWeightsTensor = 1;  // Optional
66  static constexpr int kInputToForgetWeightsTensor = 2;
67  static constexpr int kInputToCellWeightsTensor = 3;
68  static constexpr int kInputToOutputWeightsTensor = 4;
69
70  // Recurrent weight tensors of size {n_cell, n_output}
71  static constexpr int kRecurrentToInputWeightsTensor = 5;  // Optional
72  static constexpr int kRecurrentToForgetWeightsTensor = 6;
73  static constexpr int kRecurrentToCellWeightsTensor = 7;
74  static constexpr int kRecurrentToOutputWeightsTensor = 8;
75
76  // Peephole weights tensors of size {n_cell}, representing a diagonal matrix.
77  static constexpr int kCellToInputWeightsTensor = 9;    // Optional
78  static constexpr int kCellToForgetWeightsTensor = 10;  // Optional
79  static constexpr int kCellToOutputWeightsTensor = 11;  // Optional
80
81  // Gates bias tensors of size {n_cell}
82  static constexpr int kInputGateBiasTensor = 12;  // Optional
83  static constexpr int kForgetGateBiasTensor = 13;
84  static constexpr int kCellGateBiasTensor = 14;
85  static constexpr int kOutputGateBiasTensor = 15;
86
87  // Projection weight tensor of size {n_output, n_cell}
88  static constexpr int kProjectionWeightsTensor = 16;  // Optional
89  // Projection bias tensor of size {n_output}
90  static constexpr int kProjectionBiasTensor = 17;  // Optional
91
92  static constexpr int kOutputStateInTensor = 18;
93  static constexpr int kCellStateInTensor = 19;
94
95  static constexpr int kActivationParam = 20;
96  static constexpr int kCellClipParam = 21;
97  static constexpr int kProjClipParam = 22;
98
99  // Output tensors.
100  static constexpr int kScratchBufferTensor = 0;
101  static constexpr int kOutputStateOutTensor = 1;
102  static constexpr int kCellStateOutTensor = 2;
103  static constexpr int kOutputTensor = 3;
104
105 private:
106  static bool CheckInputTensorDimensions(
107      const android::hardware::neuralnetworks::V1_1::Operation &operation,
108      std::vector<RunTimeOperandInfo> &operands, uint32_t n_input,
109      uint32_t n_output, uint32_t n_cell);
110  LSTMParams params_;
111
112  const RunTimeOperandInfo *input_;
113
114  const RunTimeOperandInfo *input_to_input_weights_;
115  const RunTimeOperandInfo *input_to_forget_weights_;
116  const RunTimeOperandInfo *input_to_cell_weights_;
117  const RunTimeOperandInfo *input_to_output_weights_;
118
119  const RunTimeOperandInfo *recurrent_to_input_weights_;
120  const RunTimeOperandInfo *recurrent_to_forget_weights_;
121  const RunTimeOperandInfo *recurrent_to_cell_weights_;
122  const RunTimeOperandInfo *recurrent_to_output_weights_;
123
124  const RunTimeOperandInfo *cell_to_input_weights_;
125  const RunTimeOperandInfo *cell_to_forget_weights_;
126  const RunTimeOperandInfo *cell_to_output_weights_;
127
128  const RunTimeOperandInfo *input_gate_bias_;
129  const RunTimeOperandInfo *forget_gate_bias_;
130  const RunTimeOperandInfo *cell_bias_;
131  const RunTimeOperandInfo *output_gate_bias_;
132
133  const RunTimeOperandInfo *projection_weights_;
134  const RunTimeOperandInfo *projection_bias_;
135
136  const RunTimeOperandInfo *output_state_in_;
137  const RunTimeOperandInfo *cell_state_in_;
138
139  RunTimeOperandInfo *output_state_out_;
140  RunTimeOperandInfo *cell_state_out_;
141  RunTimeOperandInfo *output_;
142
143  RunTimeOperandInfo *scratch_buffer_;
144};
145
146}  // namespace nn
147}  // namespace android
148
149#endif  // FRAMEWORKS_ML_NN_LSTMCELL_H
150