The page "Command Line Interface" contains all of the parameters as far as I know. Some AddOns have additional parameters but the online help only contains them if the AddOn is installed.
Oh, i did not see the sub parameters. Maybe because other options like "ignorewhitespace","ignorecomments" and "ignoreproperties" are also no sub parameter of "compare".
Maybe there are more options to get codesys start or open projects faster? Like without loading libraries or without checking for errors in the Project.
Why would you want to do that? We always keep an eye on the performance but sometimes you can't have a feature without losing some performance.
I have build a workaround to use missing script commands in SP7, which are only available in SP9. Therefore i run a script which opens another codesys instance with SP9, opens the project, does some work and saves and closes it again. But i found out this is really slow. Even without UI my script runs like more than 3 minutes.
As my "work" are really simple tasks like embedding an extern obejct, i dont need all codesys features in the temporary second isntance.