The following three simx options allow the values of parameters in your source files to be overridden at compile time. These options support both absolute paths to a particular parameter and relative paths that match to all instances in the design hierarchy. If an option has an invalid value literal or wasn't found in the hierarchy, a warning message will be issued.

-gparameter_path=value

Overrides the parameter value only if it is not overridden in the source by a parameter mapping or a defparam (i.e. this option will only override the initial value of the parameter).

-Gparameter_path=value

+defparam+parameter_path=value

The above two options are equivalent. These two options always override the parameter value (and blocks other value sources such as Verilog defparams and parameter mappings).