Kyeno1,
If you are a PR who is not in compliance with their RO and you want to go to Canada you could just present your U.S. passport and the officer may ask you some simple questions, such as:
Where are you headed?
Do you have any taxable goods on you? If so what is the value?
and then wave you in.
What I have mentioned above is a probability, not a fact, you may be asked about your immigration status, how long you intend to stay, etc. You must be completely truthful.
If you say you're a PR you will be asked why you are in non-compliance, and depending on the officer you may or may not be reported for violating your RO.
Usually, the better your excuse, the less likely you are to be reported, though this is completely arbitrary unless you have an extremely valid, universally recognized H&C reason to justify your breach of RO.
The one advice I will give you is do not lie to the officer, not even a little white lie, because that is a one-way ticket to PR revocation and you may even be banned from the country. If you are reported for misrepresentation, even getting visas in the future may be an issue.