src/800_c.c:func_800384A8: score 2 (REG-caller; mine 70 ins, target 70) — not yet
  register pairs (mine -> target, count): v1->a0 x2
  replace mine[1:3] target[1:3]
        1  sll	v0,v1,0x7                      | sll	v0,a0,0x7
        2  subu	v0,v0,v1                      | subu	v0,v0,a0
