def ggetr(name):
    return int(gdb.parse_and_eval(name))

def ggeta(addr):
    return int(gdb.parse_and_eval('*(unsigned long long *){}'.format(addr)))

def gseta(name, value):
    gdb.execute('set *(unsigned long long *){} = {}'.format(name, value))

def gsetr(name, value):
    gdb.execute('set {} = {}'.format(name, value))

def gst():
    return int(gdb.parse_and_eval('*(unsigned long long*)$rsp'))

def ret():
    rsp = ggetr('$rsp')
    ret_addr = gst()
    gsetr('$rip', ret_addr)
    gsetr('$rsp', rsp + 8)

cache = {}
states = []

class BrB(gdb.Breakpoint):
    def __init__(self, location):
        super(BrB, self).__init__(spec=location, type=gdb.BP_BREAKPOINT, internal=False, temporary=False)

    def stop(self):

        rdi, rsi, rdx, rcx = ggetr('$rdi'), ggetr('$rsi'), ggetr('$rdx'), ggetr('$rcx')

        state = (rsi, rdx, rcx)
        states.append((rdi, state))

        print('in', state)

        if state in cache:
            print('!!!!')
            a, b, c = cache[state]
            gseta(rdi, a)
            gseta(rdi + 8, b)
            gseta(rdi + 16, c)
            ret()

        return False

class BrE(gdb.Breakpoint):
    def __init__(self, location):
        super(BrE, self).__init__(spec=location, type=gdb.BP_BREAKPOINT, internal=False, temporary=False)

    def stop(self):

        rdi, state = states[-1]
        states.pop()

        a, b, c = ggeta(rdi), ggeta(rdi + 8), ggeta(rdi + 16)

        print('out', state)
        cache[state] = (a, b, c)

        return False

BrB('*0x00005555555553b0')
BrE('*0x0000555555555424')

gdb.execute('run')