}

              const bool a_is_function_exclude =
                  (a->function_filter().filter_type() ==
                   FunctionFilter::SKIP_TARGET_ANNOTATION);
              const bool b_is_function_exclude =
                  (b->function_filter().filter_type() ==
                   FunctionFilter::SKIP_TARGET_ANNOTATION);
              // Function exclude filter is applied before function include

}

// A filter can be used for an op or function.
message TacFilter {
  oneof filter {
    OpFilter op_filter = 1;
    FunctionFilter function_filter = 2;
  }
}

// Function filter is to include/exclude a function in the target annotation
// pass in the TAC tool pipeline.
message FunctionFilter {
  // Function filter types that are supported. If one function is matched for

  }
  int node = signatures_iter->second;

  auto function_iter = revived_objects_.signature_def_functions.find(node);
  if (function_iter == revived_objects_.signature_def_functions.end()) {
    return errors::Internal(
        "Unable to find SignatureDefFunction associated with key ",
        signature_def_key, " despite key being valid.");
  }

  *function = function_iter->second.get();
  return Status();
}