def __init__(self, inst, code_units):
    Opcode.__init__(self, inst)
    self.reg = inst.get_A()
    self.imm = sign_extending((inst[0] >> 12), 4)
def __init__(self, inst, code_units):
    Opcode.__init__(self, inst)
    self.reg = inst.get_A()
    self.imm = sign_extending((inst[0] >> 12), 4)