// Subgraphs are given a unique incremented integer id based on when
  // they were encountered in this pass.
  const int subgraph_id_;

  const llvm::StringRef dialect_namespace_;

  Subgraph(const llvm::SetVector<Operation*> partition_ops, int num_subgraphs)
      : partition_ops_(partition_ops),
        subgraph_id_(num_subgraphs),
        func_arguments_(AccumulateOperandsDefinedAbove(partition_ops)),

      TypesFromValues(subgraph.FuncOutputs());

  FunctionType function_type =
      builder.getFunctionType(input_types, return_types);

  std::string function_name = absl::StrCat("func_", subgraph.subgraph_id_);

  func::FuncOp new_func = func::FuncOp::create(builder.getUnknownLoc(),
                                               function_name, function_type);
  new_func.setVisibility(func::FuncOp::Visibility::Private);