> I do not understand your argument about branches, how would it hinder the jump instructions?
Extra set of logic for handling NaN cases? I don't think it's impossible, just kind of less intuitive. Jump instruction using integer w/o NaN always valid, while NaN-able integer sometimes invalid (ignoring whether the memory address can be accessed).
For absolute jumps you don't need extra logic, since CPUs could declare the last page always unmapped, so such jumps would always result in a page fault (similarly to the null page on most systems).
For relative non-immediate jumps the added logic is extremely simple (hardware exception on NaN) and should not (AFAIK) hinder performance of jumps in any way.
