class MachProgram:
    pass


class MachFunction:
    def __init__(self, name):
        self.name = name
        self.entry = None


class MachBlock:
    def __init__(self):
        self.instructions = []


class AbstractInstruction:
    """ Absract machine instruction """
    def __init__(self, assem, src=(), dst=(), jumps=()):
        self.assem = assem
        self.src = tuple(src)
        self.dst = tuple(dst)
        self.jumps = tuple(jumps)

    def __repr__(self):
        return self.assem + str(self.src) + str(self.dst)