we do not expect a major difference in normal cirumstances. That said, there might be cases when IPP functions from Intel64libraries demonstrate slower performance comparing with the same functions from IA32 libraries.In some casesit indicatesissues we may met at develpment stage and have to reduce optimization level for these particular functions, in other cases it might be a indication of particular algorithm optimization specific. Normally, we fix that difference within a subsequent product releases.
Also there are cases when performance on Intel64 is better comparing with IA32 due to more processor registers available on Intel64 architecture.
I'd expect a little bit better performance for Intel64 libraries.