auto opcode_index = GetOpcodeIndex("if", tflite::BuiltinOperator_IF);
  int then_subgraph_index = subgraph_index_map_.at(op.getThenBranch().str());
  int else_subgraph_index = subgraph_index_map_.at(op.getElseBranch().str());
  auto builtin_options = tflite::CreateIfOptions(builder_, then_subgraph_index,
                                                 else_subgraph_index)
                             .Union();

}

bool ShapeInference::InferShapeForIfRegion(IfRegionOp op) {
  bool changed = false;

  Operation* then_yield = op.getThenBranch().front().getTerminator();
  Operation* else_yield = op.getElseBranch().front().getTerminator();
  for (auto result : zip(op.getResults(), then_yield->getOperandTypes(),
                         else_yield->getOperandTypes())) {