exact add_eq_xor (m:=m >>> 1) (n:=n >>> 1) (by rw [←land_shiftRight, disjoint]; rfl)
case right.hdiv
m n : Nat
disjoint : m &&& n = 0
hm : m > 0
this✝ : getBit (m &&& n) 0 = false
this : m >>> 1 < m
⊢ m >>> 1 + n >>> 1 = m >>> 1 ^^^ n >>> 1
no goals