outputs->emplace_back(ops::Subtract(scope, inputs[0], 1));
    return scope.status();
  };

  string frame_name = BackPropFrameName(while_ctx->frame_name());
  std::vector<Output> outputs;
  TF_RETURN_IF_ERROR(BuildWhileLoop(
      scope, {loop_count}, cond_fn, body_fn, frame_name, &outputs,
      /* create_while_ctx */ false, backprop_execution_pred));
  return absl::OkStatus();
}

        // does not affect the result after pattern-matching into the
        // AndRecurrence form.
        absl::string_view frame_name = control_flow_info_[n->id()].frame_name;
        auto insert_result = frame_to_merge_node_.insert({frame_name, n});
        Node* representative = insert_result.first->second;
        TF_RETURN_IF_ERROR(predicate_factory_.MakeSymbolPredicate(

        const string& frame_name =
            control_flow_info[edge->dst()->id()].frame_name;
        dst = GetOrAddFrameNodeId(frame_name);
        dst_type = "frame";
      }

      if (edge->src()->IsExit()) {
        // Lift edges from an "Exit" node to the corresponding frame node.
        const string& frame_name =
            control_flow_info[edge->src()->id()].frame_name;

//     indicating whether the loop should continue.
// * body: a function that builds the body graph of the loop. Takes the current
//     loop variables as inputs and returns the updated loop variables.
// * frame_name: the frame name to use for this while loop. This should be a
//     unique name. This will be used as a prefix for created operations.
// * outputs: output param that returns final loop variable outputs in non-error

Status BuildWhileLoop(const Scope& scope, const std::vector<Output>& inputs,
                      const CondGraphBuilderFn& cond,
                      const BodyGraphBuilderFn& body, const string& frame_name,
                      OutputList* outputs, bool create_while_ctx,
                      Output* cond_output) {
  DCHECK(!inputs.empty());
  DCHECK(outputs != nullptr);
  DCHECK(outputs->empty());

    // CHECK: tf_executor.Exit
    %Const, %ctl = Const name("Const") {dtype = i32, value = dense<0> : tensor<i32>} : () -> (tensor<i32>)
    %Enter, %ctl_0 = Enter(%Const) name("while/Enter") {T = i32, frame_name = "while/while_context", is_constant = false, parallel_iterations = 10 : i64} : (tensor<i32>) -> (tensor<*xi32>)
    %NextIteration, %ctl_1 = NextIteration(%Add) name("while/NextIteration") {T = i32} : (tensor<*xi32>) -> (tensor<*xi32>)

        int_val: 0
      }
    }
  }
}
node {
  name: "Enter"
  op: "Enter"
  input: "Const"
  attr {
    key: "T"
    value {
      type: DT_INT32
    }
  }
  attr {
    key: "frame_name"
    value {
      s: "while_context"
    }
  }
  attr {
    key: "is_constant"
    value {
      b: false
    }
  }
  attr {
    key: "parallel_iterations"
    value {
      i: 10

      }
    }
  }
}
node {
  name: "while/Enter"
  op: "Enter"
  input: "Const"
  attr {
    key: "T"
    value {
      type: DT_INT32
    }
  }
  attr {
    key: "frame_name"
    value {
      s: "while/while_context"
    }
  }
  attr {
    key: "is_constant"
    value {
      b: false
    }
  }
  attr {
    key: "parallel_iterations"
    value {
      i: 10

    %Const, %ctl = Const [%arg.ctl] name("test") {dtype = i32, value = dense<0> : tensor<i32>} : () -> (tensor<i32>)
    %Enter, %ctl_0 = Enter(%Const) [%arg.ctl] name("while/Enter") {T = i32, frame_name = "while/while_context", is_constant = false, parallel_iterations = 10 : i64} : (tensor<i32>) -> (tensor<*xi32>)

                                         const string& prefix,
                                         const string& frame_name,
                                         const Output& initial_value) {
  Output enter_initial_value = ops::internal::Enter(
      root.WithOpName(prefix + "/enter"), initial_value, frame_name);

  ops::Merge iv(root.WithOpName(prefix + "/iv"),
                {enter_initial_value, enter_initial_value});