Definition globalfunction_ptr_inject (j:meminj):=
forall b f, Genv.find_funct_ptr ge b = Some f ->
j b = Some(b,0) /\ isGlobalBlock ge b = true.

Lemma restrict_GFP_vis: forall mu
(GFP : globalfunction_ptr_inject (as_inj mu))
(Glob : forall b, isGlobalBlock ge b = true ->
frgnBlocksSrc mu b = true),
globalfunction_ptr_inject (restrict (as_inj mu) (vis mu)).