Access keyword

Hi,

I'd like to know if there is performance issue using the access keyword?

for instance the following code:

package MonTest is

   type Vecteur is
     record
       x: Integer;
       y: Integer;
     end record;

   function Norme(v: in Vecteur) return integer;
   function NormeAccess(v: access Vecteur) return integer;

end MonTest;

package body MonTest is

   function Norme(v: in Vecteur) return integer is
     n: Integer := v.x*v.x + v.y*v.y;
   begin
     return n;
   end Norme;

   function NormeAccess(v: access Vecteur) return integer is
     n: Integer := v.x*v.x + v.y*v.y;
   begin
     return n;
   end NormeAccess;

end MonTest;

Is NormeAccess faster because I'm using access keyword? I read that Ada 
compiler choose if a reference or a value mode is used in the Norme 
function, so it would mean that the access keyword should be used only 
for runtime allocated variable.

Sebastien