1 /* Copyright 2019 The TensorFlow Authors. All Rights Reserved.
2
3 Licensed under the Apache License, Version 2.0 (the "License");
4 you may not use this file except in compliance with the License.
5 You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9 Unless required by applicable law or agreed to in writing, software
10 distributed under the License is distributed on an "AS IS" BASIS,
11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 See the License for the specific language governing permissions and
13 limitations under the License.
14 ==============================================================================*/
15 #include "tensorflow/lite/tools/optimize/quantization_wrapper_utils.h"
16
17 #include <fstream>
18 #include <memory>
19 #include <string>
20 #include <utility>
21
22 #include "tensorflow/lite/schema/schema_generated.h"
23 #include "tensorflow/lite/tools/optimize/operator_property.h"
24
25 namespace tflite {
26 namespace optimize {
27 namespace {
28
29 #ifdef TFLITE_CUSTOM_LSTM
30 constexpr bool kUseCustomLSTM = true;
31 #else
32 constexpr bool kUseCustomLSTM = false;
33 #endif
34
MakeTensor(const string & name,std::unique_ptr<TensorT> * tensor)35 void MakeTensor(const string& name, std::unique_ptr<TensorT>* tensor) {
36 TensorT* tensor_raw = new TensorT;
37 tensor_raw->name = name;
38 tensor_raw->shape = {0};
39 tensor_raw->type = TensorType_FLOAT32;
40
41 tensor->reset(tensor_raw);
42 }
43
CreateTensorName(int op_index,int tensor_index)44 string CreateTensorName(int op_index, int tensor_index) {
45 return "intermediate_" + std::to_string(op_index) + "_" +
46 std::to_string(tensor_index);
47 }
48
IntermediateTensorExists(ModelT * model)49 bool IntermediateTensorExists(ModelT* model) {
50 for (int subgraph_idx = 0; subgraph_idx < model->subgraphs.size();
51 ++subgraph_idx) {
52 SubGraphT* subgraph = model->subgraphs.at(subgraph_idx).get();
53 for (size_t op_idx = 0; op_idx < subgraph->operators.size(); op_idx++) {
54 OperatorT* op = subgraph->operators[op_idx].get();
55 if (!op->intermediates.empty()) {
56 return true;
57 }
58 }
59 }
60 return false;
61 }
62 } // namespace
63
LoadModel(const string & path,ModelT * model)64 TfLiteStatus LoadModel(const string& path, ModelT* model) {
65 auto input_model = FlatBufferModel::BuildFromFile(path.c_str());
66 if (!input_model) {
67 return kTfLiteError;
68 }
69 auto readonly_model = input_model->GetModel();
70 if (!readonly_model) {
71 return kTfLiteError;
72 }
73 readonly_model->UnPackTo(model);
74 return kTfLiteOk;
75 }
76
AddIntermediateTensorsToFusedOp(flatbuffers::FlatBufferBuilder * builder,ModelT * model)77 TfLiteStatus AddIntermediateTensorsToFusedOp(
78 flatbuffers::FlatBufferBuilder* builder, ModelT* model) {
79 // Return early when the model has no operator.
80 if (model->subgraphs.size() == 1 && model->subgraphs[0]->operators.empty()) {
81 return kTfLiteOk;
82 }
83 // Return early if the model already has intermediate tensors.
84 if (IntermediateTensorExists(model)) {
85 return kTfLiteOk;
86 }
87 // Process the model.
88 for (int subgraph_idx = 0; subgraph_idx < model->subgraphs.size();
89 ++subgraph_idx) {
90 SubGraphT* subgraph = model->subgraphs.at(subgraph_idx).get();
91 for (size_t op_idx = 0; op_idx < subgraph->operators.size(); op_idx++) {
92 // Find ops that need additional tensor.
93 OperatorT* op = subgraph->operators[op_idx].get();
94 operator_property::OperatorProperty property =
95 operator_property::GetOperatorProperty(model, subgraph_idx, op_idx);
96 if (property.intermediates.empty()) {
97 continue;
98 }
99 // Add tensors.
100 const int next_tensor_index = subgraph->tensors.size();
101 int num_intermediates = property.intermediates.size();
102 if (kUseCustomLSTM) {
103 num_intermediates = 12;
104 }
105 for (int i = 0; i < num_intermediates; ++i) {
106 std::unique_ptr<TensorT> intermediate_tensor;
107 auto name = CreateTensorName(op_idx, i);
108 MakeTensor(name, &intermediate_tensor);
109 subgraph->tensors.push_back(std::move(intermediate_tensor));
110 op->intermediates.push_back(next_tensor_index + i);
111 }
112 }
113 }
114
115 // Export the model.
116 flatbuffers::Offset<Model> output_model_location =
117 Model::Pack(*builder, model);
118 FinishModelBuffer(*builder, output_model_location);
119
120 return kTfLiteOk;
121 }
122
WriteFile(const std::string & out_file,const uint8_t * bytes,size_t num_bytes)123 bool WriteFile(const std::string& out_file, const uint8_t* bytes,
124 size_t num_bytes) {
125 std::fstream stream(out_file, std::ios::binary | std::ios::out);
126 for (size_t i = 0; i < num_bytes; i++) {
127 stream << bytes[i];
128 }
129 return (!stream.bad() && !stream.fail());
130 }
131
132 } // namespace optimize
133 } // namespace tflite
134