> set_max_delay 4 -through [get_pins inst0/I0]
> set_max_delay 5 -through [get_pins inst0/I0] -through [get_pins inst1/I3]
Both exceptions are kept by the timing engine. The more challenging constraint is used for timing analysis. In this example, the 4 ns max delay constraint will be used even for paths going through the pin inst1/I3.