The UK sets out the limitations of autopilot use during revalidation/renewal IRTs in Standards Document 14. It can be used in any mode throughout the flight except:
1. For the 3D approach (although the flight director may be used)
2. During the airwork
3. Any time when asymmetric, if the autopilot is not cleared for use in asymmetric flight.
The rules for EASA-land are less clear but there are some hints in FCL Appendix 6 and Appendix 9 as well as the new Flight Examiners' Manual.
1. Use of automatics should be discussed as part of the initial IR briefing.
2. For revalidation/renewal it says '3D operations to DA (autopilot may be used to GS/GP intercept)' and it also requires that use of the autopilot (if fitted) is tested, and states that this may be done in Section 3 (the IR section).
No idea of rules in USA or Canada.