auto forward_res_nm2 = UnpackResults(forward_res_indexes_im2);
  auto forward_res_nm1 = UnpackResults(forward_res_indexes_im1);
  auto core_tpu_res_nm2 = UnpackResults(core_tpu_res_indexes_im2);
  auto non_tpu_res_nm1 = UnpackResults(non_tpu_res_indexes_im1);
  auto C_nm2 = new_while_op->getResult(C_index_im2);
  auto C_nm1 = new_while_op->getResult(C_index_im1);

  // Finish step n-2.