def add_flow_to_label(self, label_name: ScopedName, ap_change: RegChangeLike):
"""
Registers a flow from current location to a label, with some ap_change.
For example, after 'jmp label1 if [ap] != 0; ap++', we have a flow to label1 with ap_change
of 1.
"""
ap_change = RegChange.from_expr(ap_change)
new_data = self.get().add_ap(ap_change, self._group_alloc)
self.labels_data[label_name] = self.labels_data[label_name].converge(
self.reference_manager, new_data, self._group_alloc)
def test_from_expr():
assert RegChange.from_expr(5) == RegChangeKnown(5)
assert RegChange.from_expr(RegChangeKnown(6)) == RegChangeKnown(6)
assert RegChange.from_expr(ExprConst(7)) == RegChangeKnown(7)
assert RegChange.from_expr(ExprIdentifier('asd')) == RegChangeUnknown()
with pytest.raises(TypeError):
RegChange.from_expr('wrong type')
def translate_ap(expr, ap_diff: RegChangeLike):
ap: Optional[Callable]
ap_diff = RegChange.from_expr(ap_diff)
if isinstance(ap_diff, RegChangeKnown):
diff = ap_diff.value
def ap(location):
return ExprOperator(ExprReg(reg=Register.AP, location=location),
'-',
ExprConst(val=diff, location=location),
location=location)
else:
ap = None
fp = (lambda location: ExprReg(reg=Register.FP, location=location))
return SubstituteRegisterTransformer(ap, fp).visit(expr)
def add_ap(self, ap_change: RegChangeLike):
ap_change = RegChange.from_expr(ap_change)
self.data = self.get().add_ap(ap_change, self._group_alloc)