Thank you for the reply. I am studying the manual you mentioned. Basic execuation environment of IA-32 shows some FPU instruction/data pointers but it is not clear if some modern intel processors use some pins to fetch code or data regarding to FPU, if not what would be the application of these pointers then.
I know that i should take a look at the date sheets of some intel processors too but it means that i stop reading Basic Architecture and start studying some other manuals while those manuals also depend on the concepts presented in the Basic Archtecture!!
It is like a loop, isn't it better to clarify such things at the first place of the intel documentation. Also if you have some knowledge it would save me lots of time.