fanin                                              Assigns to an output port
                                                   a value equal to the sum
                                                   of the fanin of the
                                                   devices connected to that
                                                   port. To specify
                                                   bidirectional I/Os,
                                                   specify the same port
                                                   name for both fanin and
                                                   fanout values.
 fanin_value                                         floating-point value
 [ -g | port_list ]                                  Applies constraint
                                                     globally or to output
                                                     ports in a design unitor
                                                     instance/all outputs at
                                                     the current scope
