(*Program Definition Asm_core_sem (ge : genv) :
  @CoreSemantics regset mem :=
  @Build_CoreSemantics _ _
    (fun _ => Asm_initial_core ge)
    (Asm_at_external ge)
    (fun v q m => Asm_after_external ge v q)
    (fun _ _ => False)
    (Asm_step ge)
    _
    (Asm_corestep_not_at_external ge).*)

Definition Asm_core_sem (ge : genv) := sem2coresem (part_semantics ge) (Asm_corestep_not_halted ge).

Lemma get_extcall_arg_spec : forall r m l v, get_extcall_arg r m l = Some v <-> extcall_arg r m l v.