def z3_expression_to_nusmv(expression, tables=None, other_tables=None):
z3_to_nusmv = {
z3p.Z3_OP_AND: ' & ',
z3p.Z3_OP_ADD: ' + ',
z3p.Z3_OP_MOD: ' mod ',
z3p.Z3_OP_EQ: ' = ',
z3p.Z3_OP_LT: ' < ',
z3p.Z3_OP_GT: ' > '
}
kind = expression.decl().kind()
if (z3p.is_const(expression)
and expression.decl().name().startswith('table_')):
assert tables is not None
table_name = expression.decl().name()
assert table_name in tables or table_name in other_tables
table_expression = tables[
table_name] if table_name in tables else other_tables[table_name]
case_expression = 'case '
for condition, result in table_expression:
c = z3_expression_to_nusmv(condition, tables)
r = z3_expression_to_nusmv(result, tables)
case_expression += '{} : {}; '.format(c, r)
case_expression += 'esac'
return case_expression
elif kind in z3_to_nusmv:
children = [
z3_expression_to_nusmv(c, tables) for c in expression.children()
]
return '({})'.format(z3_to_nusmv[kind].join(children))
elif expression == z3p.BoolVal(True):
return 'TRUE'
elif expression == z3p.BoolVal(False):
return 'FALSE'
elif kind == z3p.Z3_OP_NOT:
e = z3_expression_to_nusmv(expression.arg(0))
return '!({})'.format(e)
elif z3p.is_const(expression):
return str(expression)
elif kind == z3p.Z3_OP_ITE:
guard = z3_expression_to_nusmv(expression.arg(0))
then_branch = z3_expression_to_nusmv(expression.arg(1))
else_branch = z3_expression_to_nusmv(expression.arg(2))
return '(case {} : {}; TRUE : {}; esac)'.format(
guard, then_branch, else_branch)
else:
raise NotImplementedError(
'Cannot translate expression {} to nusmv.'.format(expression))
def translate_expression(self, e):
if e == z3p.BoolVal(True):
return 'TheLTS->MakeTrue()'
elif e == z3p.BoolVal(False):
return 'TheLTS->MakeFalse()'
elif z3p.is_int_value(e):
return 'TheLTS->MakeVal("{i}", TheLTS->MakeRangeType({i}, {i}))'.format(i=e)
elif z3p.is_const(e) and e in self.channels:
return self.translate_channel_reference(e)
elif z3p.is_const(e):
return '{}Exp'.format(to_camel_case(e.decl().name()))
elif e.num_args() == 1:
return self.translate_unary_expression(e)
elif e.num_args() == 2 and e.decl().kind() == z3p.Z3_OP_SELECT:
return self.translate_channel_reference(e)
elif e.num_args() == 2:
return self.translate_binary_expression(e)
elif e.num_args() == 3:
return self.translate_ternary_expreession(e)
else:
raise NotImplementedError("can't translate expression {} with {}".format(e, e.num_args()))
def z3_expression_to_nusmv(expression, tables=None, other_tables=None):
z3_to_nusmv = {z3p.Z3_OP_AND: ' & ',
z3p.Z3_OP_ADD: ' + ',
z3p.Z3_OP_MOD: ' mod ',
z3p.Z3_OP_EQ: ' = ',
z3p.Z3_OP_LT: ' < ',
z3p.Z3_OP_GT: ' > '}
kind = expression.decl().kind()
if (z3p.is_const(expression) and
expression.decl().name().startswith('table_')):
assert tables is not None
table_name = expression.decl().name()
assert table_name in tables or table_name in other_tables
table_expression = tables[table_name] if table_name in tables else other_tables[table_name]
case_expression = 'case '
for condition, result in table_expression:
c = z3_expression_to_nusmv(condition, tables)
r = z3_expression_to_nusmv(result, tables)
case_expression += '{} : {}; '.format(c, r)
case_expression += 'esac'
return case_expression
elif kind in z3_to_nusmv:
children = [z3_expression_to_nusmv(c, tables) for c in expression.children()]
return '({})'.format(z3_to_nusmv[kind].join(children))
elif expression == z3p.BoolVal(True):
return 'TRUE'
elif expression == z3p.BoolVal(False):
return 'FALSE'
elif kind == z3p.Z3_OP_NOT:
e = z3_expression_to_nusmv(expression.arg(0))
return '!({})'.format(e)
elif z3p.is_const(expression):
return str(expression)
elif kind == z3p.Z3_OP_ITE:
guard = z3_expression_to_nusmv(expression.arg(0))
then_branch = z3_expression_to_nusmv(expression.arg(1))
else_branch = z3_expression_to_nusmv(expression.arg(2))
return '(case {} : {}; TRUE : {}; esac)'.format(guard, then_branch, else_branch)
else:
raise NotImplementedError('Cannot translate expression {} to nusmv.'.format(expression))
def inputs_in_constraints_for_function(self, function_name, table):
retval = []
for constraint in self.constraints:
expressions = [constraint]
while len(expressions) > 0:
expression = expressions.pop()
if not z3p.is_const(expression):
if expression.decl().name() == function_name:
retval.append(expression)
else:
for i in range(expression.num_args()):
expressions.append(expression.arg(i))
return retval
def inputs_in_constraints_for_function(self, function_name, table):
retval = []
for constraint in self.constraints:
expressions = [constraint]
while len(expressions) > 0:
expression = expressions.pop()
if not z3p.is_const(expression):
if expression.decl().name() == function_name:
retval.append(expression)
else:
for i in range(expression.num_args()):
expressions.append(expression.arg(i))
return retval
def selects_in_expression(expression):
expressions = [expression]
selects = []
while len(expressions) > 0:
expression = expressions.pop(0)
if z3p.is_const(expression):
continue
elif z3p.is_app(expression):
if expression.decl().kind() == z3p.Z3_OP_SELECT:
selects.append(expression)
else:
for i in range(expression.num_args()):
expressions.append(expression.arg(i))
return selects
def selects_in_expression(expression):
expressions = [expression]
selects = []
while len(expressions) > 0:
expression = expressions.pop(0)
if z3p.is_const(expression):
continue
elif z3p.is_app(expression):
if expression.decl().kind() == z3p.Z3_OP_SELECT:
selects.append(expression)
else:
for i in range(expression.num_args()):
expressions.append(expression.arg(i))
return selects
def evaluate_expression(expression,
symbolic_memory,
concrete_memory,
tables=None):
if isinstance(expression, int):
return expression
if isinstance(expression, tuple):
return expression
if z3p.is_const(expression):
if z3p.is_bool_or_int_value(expression):
return expression
if expression in symbolic_memory:
return symbolic_memory[expression]
elif expression.decl().name().startswith('table_'):
assert expression.decl().name() in tables
table_expression = tables[expression.decl().name()]
first_value = table_expression[0][1]
if first_value.sort() == z3p.IntSort():
last_else = z3p.IntVal(0)
else:
last_else = z3p.BoolVal(False)
if_expression = None
for conditional, value in table_expression:
guard = evaluate_expression(conditional, symbolic_memory,
concrete_memory)
last_else = z3p.If(guard, value, last_else)
return z3p.simplify(last_else)
else:
return concrete_memory[expression]
elif expression.decl().kind() == z3p.Z3_OP_SELECT:
if expression in symbolic_memory:
return symbolic_memory[expression]
else:
return concrete_memory[expression]
else:
new_args = [
evaluate_expression(expression.arg(i), symbolic_memory,
concrete_memory, tables)
for i in range(expression.num_args())
]
if expression.decl().kind() == z3p.Z3_OP_AND:
return z3p.And(*new_args)
else:
return expression.decl()(*new_args)
def evaluate_expression(expression, symbolic_memory, concrete_memory, tables=None):
if isinstance(expression, int):
return expression
if isinstance(expression, tuple):
return expression
if z3p.is_const(expression):
if z3p.is_bool_or_int_value(expression):
return expression
if expression in symbolic_memory:
return symbolic_memory[expression]
elif expression.decl().name().startswith('table_'):
assert expression.decl().name() in tables
table_expression = tables[expression.decl().name()]
first_value = table_expression[0][1]
if first_value.sort() == z3p.IntSort():
last_else = z3p.IntVal(0)
else:
last_else = z3p.BoolVal(False)
if_expression = None
for conditional, value in table_expression:
guard = evaluate_expression(conditional, symbolic_memory, concrete_memory)
last_else = z3p.If(guard, value, last_else)
return z3p.simplify(last_else)
else:
return concrete_memory[expression]
elif expression.decl().kind() == z3p.Z3_OP_SELECT:
if expression in symbolic_memory:
return symbolic_memory[expression]
else:
return concrete_memory[expression]
else:
new_args = [evaluate_expression(expression.arg(i), symbolic_memory, concrete_memory, tables)
for i in range(expression.num_args())]
if expression.decl().kind() == z3p.Z3_OP_AND:
return z3p.And(*new_args)
else:
return expression.decl()(*new_args)
def __init__(self, name, locations, initial_location, transitions, variables=None, initial_values=None, input_channels=None, output_channels=None, tables=None, variable_ranges=None, output_channel_ranges=None, compassion=None, justice=None):
""" Every node represents a control location and has a unique name.
Transitions are of the form (soruce, channel[, channel expression], guard, update, target)
where source and target must be automaton control locations,
channel an input or output channel,
channel expression is there if the channel is an output one,
guard is a z3 boolean expression,
update is a pair (variable, expression).
"""
super(SymbolicAutomaton, self).__init__()
self.name = name
self.variables = variables if variables is not None else []
self.transitions = transitions
self.initial_values = initial_values if initial_values is not None else []
self.initials = {}
for v, value in zip(self.variables, self.initial_values):
self.initials[v] = value
assert len(self.variables) == len(self.initial_values), "# of initial values should match # of variables: variables {}, initials: {}".format(self.variables, self.initial_values)
self.variable_initial_value = dict(zip([str(v) for v in self.variables],
self.initial_values))
# TODO change this to work with uninitialized variables
# change variables input to include initial values
self.input_channels = input_channels if input_channels is not None else []
self.output_channels = output_channels if output_channels is not None else []
# add channel with unit type unit can be an mtype with just one symbol
for l in locations:
self.add_node(l)
for transition in transitions:
channel_expression = []
# if it is an input transition, there is no expression for the message to send
if len(transition) == 6:
name, source, channel, guard, update, target = transition
assert channel not in self.output_channels, "Output channel {} used in input transition {}".format(channel, transition)
kind = 'input'
# output transitions
elif len(transition) == 7:
name, source, channel, channel_expression, guard, update, target = transition
assert channel not in self.input_channels, "Input channel {} used in output transition {}".format(channel, transition)
kind = 'output'
# internal transitios
elif len(transition) == 5:
name, source, guard, update, target = transition
channel = None
assert source in locations and target in locations, transition
assert (channel in self.input_channels or
channel in self.output_channels or
channel is None), transition
if channel is None:
kind = 'internal'
if name is None:
name = 't_{}'.format(self.number_of_edges())
self.add_edge(source, target,
channel=channel,
channel_expression=channel_expression,
guard=guard,
update=update,
name=name,
kind=kind,
automaton=self)
assert initial_location in self.nodes()
self.initial_location = initial_location
self.tables = {} if tables is None else tables
self.channel_edges = {}
self.update_channel_edges()
self.changes = []
self.transition_variables = {}
self.update_transition_variables()
self.variable_ranges = {} if variable_ranges is None else variable_ranges
self.output_channel_ranges = {} if output_channel_ranges is None else output_channel_ranges
for v in self.variables:
if v.sort() == z3p.IntSort():
assert v in self.variable_ranges, "No range declared for {}".format(v)
for variable, variable_range in self.variable_ranges.items():
assert variable in self.variables, "Variable {} was not declared".format(variable)
assert variable.sort() == z3p.IntSort()
assert isinstance(variable_range, tuple) and len(variable_range) == 2
assert isinstance(variable_range[0], int)
assert isinstance(variable_range[1], int)
assert variable_range[0] <= variable_range[1]
for output_channel_or_field, output_channel_range in self.output_channel_ranges.items():
if not z3p.is_const(output_channel_or_field) and output_channel_or_field.decl().kind() == z3p.Z3_OP_SELECT:
assert output_channel_or_field.arg(0) in self.output_channels
else:
assert output_channel_or_field in self.output_channels
# assert output_channel.sort() == z3p.IntSort()
assert isinstance(output_channel_range, tuple) and len(output_channel_range) == 2
assert isinstance(output_channel_range[0], int)
assert isinstance(output_channel_range[1], int)
assert output_channel_range[0] < output_channel_range[1]
if compassion is not None:
self.compassion = compassion
else:
self.compassion = []
if justice is not None:
self.justice = justice
else:
self.justice = []
