assert(!hoist_params->lhs_args[kv.second]);
      assert(!hoist_params->rhs_args[kv.second]);

      if (hoist_params->scalar_operand_idx == 1) {
        hoist_params->lhs_args[kv.second] = kv.first;
        hoist_params->rhs_args[kv.second] = identity_const;
      } else {
        assert(hoist_params->scalar_operand_idx == 0);
        hoist_params->lhs_args[kv.second] = identity_const;

  // CHECK-DAG: %[[LHS_AXIS:.*]] = "tf.Const"() <{value = dense<1> : tensor<i32>}>

  // CHECK: %[[ADD_LHS_CONCAT:.*]] = "tf.Pack"(%arg2, %arg3) <{axis = 0 : i64}> {device = "/job:localhost/replica:0/task:0/device:GPU:0"}
  // CHECK: %[[MUL_LHS_CONCAT:.*]] = "tf.ConcatV2"(%arg0, %arg1, %[[LHS_AXIS]]) {device = "/job:localhost/replica:0/task:0/device:GPU:0"}