Sometimes it is advantageous to iterate through a command multiple times to obtain
the best results. For example, it might be helpful to first run phys_opt_design with the force_replication_on_nets option to optimize some critical nets that
appear to have an impact on WNS during route.
Next, run phys_opt_design with any of the
directives to improve the overall WNS of the design.
In Non-Project Mode, use the following commands:
phys_opt_design -force_replication_on_nets [get_nets -hier *phy_reset*]
phys_opt_design -directive <directive name>In Project Mode, the same results can be achieved by running the first phys_opt_design command as part of a Tcl-pre script for a phys_opt_design run step which will run using the -directive option.