Comparison between call by reference and call by value part 2

gistfile1.cpp

The Code:
 
int add_ref(const int& a, const int& b)
{
  return a + b;
}
 
int add_value(const int a, const int b)
{
  return a + b;
}
----------------------------------------------------------------------------
Compile with: gcc 4.7.1
arm-none-eabi-g++ -O3 -S hoge.cpp -o hoge.generic_arm.s
----------------------------------------------------------------------------
The Result (simpilified):
_Z7add_refRKiS0_:
	ldr	r3, [r0, #0]
	ldr	r0, [r1, #0]
	adds	r0, r3, r0
	bx	lr

_Z9add_valueii:
	adds	r0, r0, r1
	bx	lr