They do have some sort of laws for holocaust denial, this is what I found on wikipedia,
As a result a compromise has been reached within the EU and while the EU has not prohibited Holocaust denial outright, a maximum term of three years in jail is optionally available to all member nations for “denying or grossly trivializing crimes of genocide, crimes against humanity and war crimes.”[128]](Holocaust denial - Wikipedia)[129]](Holocaust denial - Wikipedia)
Ahmedinejad actually himself denies it so obviously he’s gonna opposse this law.