Implementation of unpack op.

PiperOrigin-RevId: 210051131

1 files changed, 29 insertions, 0 deletions

diff --git a/tensorflow/contrib/lite/toco/graph_transformations/propagate_fixed_sizes.cc b/tensorflow/contrib/lite/toco/graph_transformations/propagate_fixed_sizes.cc
index 91e290439a..fa2be961f5 100644
--- a/tensorflow/contrib/lite/toco/graph_transformations/propagate_fixed_sizes.cc
+++ b/tensorflow/contrib/lite/toco/graph_transformations/propagate_fixed_sizes.cc
@@ -1629,6 +1629,32 @@ void ProcessOneHotOperator(Model* model, OneHotOperator* op) {
   }
 }
 
+void ProcessUnpackOperator(Model* model, UnpackOperator* op) {
+  CHECK_EQ(op->inputs.size(), 1);
+  const auto& input_array = model->GetArray(op->inputs[0]);
+  // Yield until input dims have been resolved.
+  if (!input_array.has_shape()) {
+    return;
+  }
+
+  const std::vector<int>& input_dims = input_array.shape().dims();
+  std::vector<int> output_dims;
+
+  output_dims.reserve(input_dims.size() - 1);
+  for (int i = 0; i < input_dims.size(); ++i) {
+    if (i != op->axis) {
+      output_dims.push_back(input_dims[i]);
+    }
+  }
+  for (const string& output_name : op->outputs) {
+    auto& output_array = model->GetArray(output_name);
+    if (output_array.has_shape()) {
+      return;
+    }
+    *output_array.mutable_shape()->mutable_dims() = output_dims;
+  }
+}
+
 }  // namespace
 
 bool PropagateFixedSizes::Run(Model* model, std::size_t op_index) {
@@ -1880,6 +1906,9 @@ bool PropagateFixedSizes::Run(Model* model, std::size_t op_index) {
     case OperatorType::kOneHot:
       ProcessOneHotOperator(model, static_cast<OneHotOperator*>(op));
       break;
+    case OperatorType::kUnpack:
+      ProcessUnpackOperator(model, static_cast<UnpackOperator*>(op));
+      break;
     default:
       // Unimplemented, another graph transformation should drop it.
       LOG(FATAL) << "Unhandled operator type " << OperatorTypeName(op->type);