def pop(self, index=-1) -> BitVec:
"""
:param index:index to be popped, same as the list() class.
:returns popped value
:function: same as list() class but throws StackUnderflowException for popping from an empty list
"""
try:
return super(MachineStack, self).pop(index)
except IndexError:
raise StackUnderflowException("Trying to pop from an empty stack")
def __getitem__(self, item: Union[int, slice]) -> Any:
"""
:param item:
:return:
"""
try:
return super(MachineStack, self).__getitem__(item)
except IndexError:
raise StackUnderflowException(
"Trying to access a stack element which doesn't exist")
def jump_(self, global_state):
state = global_state.mstate
disassembly = global_state.environment.code
try:
jump_addr = util.get_concrete_int(state.stack.pop())
except AttributeError:
raise InvalidJumpDestination("Invalid jump argument (symbolic address)")
except IndexError:
raise StackUnderflowException()
index = util.get_instruction_index(disassembly.instruction_list, jump_addr)
if index is None:
raise InvalidJumpDestination("JUMP to invalid address")
op_code = disassembly.instruction_list[index]['opcode']
if op_code != "JUMPDEST":
raise InvalidJumpDestination("Skipping JUMP to invalid destination (not JUMPDEST): " + str(jump_addr))
new_state = copy(global_state)
new_state.mstate.pc = index
new_state.mstate.depth += 1
return [new_state]
def __getitem__(self, item):
try:
return super(MachineStack, self).__getitem__(item)
except IndexError:
raise StackUnderflowException(
"Trying to access a stack element which doesn't exist")