1 files changed, 59 insertions, 0 deletions
diff --git a/tensorflow/contrib/lite/toco/graph_transformations/remove_final_dequantize_op.cc b/tensorflow/contrib/lite/toco/graph_transformations/remove_final_dequantize_op.cc
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index 0000000000..3992e7d1ef
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+++ b/tensorflow/contrib/lite/toco/graph_transformations/remove_final_dequantize_op.cc
@@ -0,0 +1,59 @@
+/* Copyright 2017 The TensorFlow Authors. 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.
+==============================================================================*/
+#include <memory>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include "tensorflow/contrib/lite/toco/graph_transformations/graph_transformations.h"
+#include "tensorflow/contrib/lite/toco/model.h"
+#include "tensorflow/contrib/lite/toco/model_flags.pb.h"
+#include "tensorflow/contrib/lite/toco/tooling_util.h"
+#include "tensorflow/core/platform/logging.h"
+
+namespace toco {
+
+bool RemoveFinalDequantizeOp::Run(Model* model, std::size_t op_index) {
+  const auto dequantize_it = model->operators.begin() + op_index;
+  const auto* dequantize_op = dequantize_it->get();
+  if (dequantize_op->type != OperatorType::kDequantize) {
+    return false;
+  }
+  const auto& output = dequantize_op->outputs[0];
+  // We can remove any dequantize op whose output is not consumed by
+  // any op. This is not necessarily equivalent to the output being
+  // one of the model's output arrays, as some intermediate array
+  // in the middle of the graph might be designated as an output
+  // array.
+  if (CountOpsWithInput(*model, output)) {
+    return false;
+  }
+
+  // If one of the model's output arrays was actually the Dequantize op's
+  // output, then we need to update it to point to the Dequantize op's input.
+  for (int i = 0; i < model->flags.output_arrays_size(); i++) {
+    if (output == model->flags.output_arrays(i)) {
+      model->flags.set_output_arrays(i, dequantize_op->inputs[0]);
+    }
+  }
+
+  // Remove the node and its output array.
+  AddMessageF("Removed final %s", LogName(*dequantize_op));
+  model->arrays.erase(output);
+  model->operators.erase(dequantize_it);
+  return true;
+}
+
+}  // namespace toco