Reuse the input / output in the state flow chart and customize the internal state

The code generated from the model shown below has the following function prototype:

void diagnosis_detection_unit(boolean_T rtu_cond, boolean_T rtu_onread, const Fault_T *rtu_f_in, Fault_T *rty_f_out, DW_detection_unit_diagnosis_T *localDW)

Question 1: I would like to use the variables rtu_f_in/rty_f_out as only one, like references, is possible to optimize this code?

Question 2: Taking into account this model is used inside a For Each Subsystem, Is possible to customize the variable localDW ( where is defined the internal state) as part of the input/output?