updated imports

This commit is contained in:
Artur Meski
2016-12-28 15:55:30 +01:00
parent daadf33d02
commit e62638fd7b
6 changed files with 4 additions and 1728 deletions

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@@ -1,11 +1,7 @@
#!/usr/bin/env python #!/usr/bin/env python
from rctsys import * from rs import *
from distrib_rctsys import * from smt import *
from smtchecker import SmtChecker
from smtcheckerpgrs import SmtCheckerPGRS
from smtcheckerdistribrs import SmtCheckerDistribRS
from smtcheckerrsc import SmtCheckerRSC
import sys import sys
import resource import resource

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@@ -6,11 +6,8 @@
""" """
from rctsys import * from rs import *
from smtchecker import SmtChecker from smt import *
from smtcheckerpgrs import SmtCheckerPGRS
from smtcheckerdistribrs import SmtCheckerDistribRS
from smtcheckerrsc import SmtCheckerRSC
import sys import sys
import rs_examples import rs_examples

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@@ -1,530 +0,0 @@
"""
SMT-based Model Checking Module for RS
"""
from z3 import *
from time import time
from sys import stdout
class SmtChecker(object):
def __init__(self, rs):
##############################################################
# Encoded RS
##############################################################
rs.sanity_check()
self.reaction_system = rs
##############################################################
# SMT variables
##############################################################
self.v = []
self.v_init = []
#self.vSucc = []
#self.vSuccInit = []
self.v_ctx = []
self.next_level_to_encode = 0
##############################################################
# SMT solver instance
##############################################################
self.solver = Solver()
#def smtVar(self, level, entityID, primed=False):
# return "?"
def prepare_context_variables(self):
"""Encodes all the context variables"""
level = self.next_level_to_encode
variables = []
for entity in self.reaction_system.background_set:
variables.append(Bool("C"+str(level)+"_"+entity))
self.v_ctx.append(variables)
def prepare_state_variables(self):
"""Encodes all the state variables (including successors)"""
level = self.next_level_to_encode
variables = []
#variablesSucc = []
for entity in self.reaction_system.background_set:
variables.append(Bool("L"+str(level)+"_"+entity))
#variablesSucc.append(Bool("R"+str(level)+"_"+entity))
self.v.append(variables)
#self.vSucc.append(variablesSucc)
self.v_init.append(Bool("L"+str(level)+"_Init"))
#self.vSuccInit.append(Bool("R"+str(level)+"_Init"))
def prepare_all_variables(self):
"""Encodes all the variables"""
self.prepare_state_variables()
self.prepare_context_variables()
self.next_level_to_encode += 1
def enc_init_state(self, level):
"""Encodes the initial state at the given level"""
init_state_enc = self.v_init[level]
for v in self.v[level]:
init_state_enc = simplify(And(init_state_enc, Not(v)))
return init_state_enc
def enc_init_contexts(self, level):
"""Encodes the initial contexts set at the given level"""
init_contexts_set_enc = False # Or
for ctx in self.reaction_system.init_contexts:
single_ctx_enc = True # And
not_ctx_entities = list(range(0, len(self.reaction_system.background_set)))
for entity in ctx:
single_ctx_enc = simplify(And(single_ctx_enc, self.v_ctx[level][entity]))
not_ctx_entities.remove(entity)
for entity in not_ctx_entities:
single_ctx_enc = simplify(And(single_ctx_enc, Not(self.v_ctx[level][entity])))
init_contexts_set_enc = simplify(Or(init_contexts_set_enc, single_ctx_enc))
#print("initContextSetEnc: " + repr(initContextsSetEnc))
return init_contexts_set_enc
def enc_not_allowed_contexts(self, level):
"""Encodes all the context entities that are not allowed in the context sets"""
bg_set = set(range(0,len(self.reaction_system.background_set)))
ctx_ent_set = set(self.reaction_system.context_entities)
not_ctx_ent_set = bg_set.difference(ctx_ent_set)
enc = True
for entity in not_ctx_ent_set:
enc = simplify(And(enc, Not(self.v_ctx[level][entity])))
return enc
def enc_enabledness(self, level, prod_entity):
"""Encodes the enabledness condition for a given level and a given entity"""
rcts_for_prod_entity = self.reaction_system.get_reactions_by_product()[prod_entity]
if rcts_for_prod_entity == []:
return False
#encInitEnab = simplify(Or(And(self.vInit[level], self.encInitContexts(level)),
# And(Not(self.vInit[level]), self.encNotAllowedContexts(level))))
enc_rct_prod = False
for ri_pair in rcts_for_prod_entity: # reactants-inhibitors pair
enc_reactants = True
enc_inhibitors = True
for reactant in ri_pair[0]:
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][reactant], self.v_ctx[level][reactant])))
for inhibitor in ri_pair[1]:
enc_inhibitors = simplify(And(enc_inhibitors,
Not(Or(self.v[level][inhibitor], self.v_ctx[level][inhibitor]))))
enc_rct_prod = simplify(Or(enc_rct_prod, And(enc_reactants, enc_inhibitors)))
#print("encEnabledness(" + repr(prodEntity) + "): " + repr(simplify(And(encInitEnab, encRctProd))))
#return simplify(And(encInitEnab, encRctProd))
return enc_rct_prod
def enc_entity_production(self, level, prod_entity):
"""Encodes the production of a given entity from a given level at level+1"""
enc_enab_cond = self.enc_enabledness(level, prod_entity)
enc_ent_prod = Or(And(enc_enab_cond, self.v[level+1][prod_entity]),
And(Not(enc_enab_cond), Not(self.v[level+1][prod_entity])))
return enc_ent_prod
def enc_transition_relation(self, level):
"""Encodes the transition relation"""
unused_entities = list(range(0,len(self.reaction_system.background_set)))
enc_trans = True
for prod_entity in self.reaction_system.get_reactions_by_product():
unused_entities.remove(prod_entity)
enc_trans = simplify(And(enc_trans, self.enc_entity_production(level, prod_entity)))
enc_trans = simplify(And(enc_trans, Not(self.v_init[level+1])))
for prod_entity in unused_entities:
enc_trans = simplify(And(enc_trans, Not(self.v[level+1][prod_entity])))
if level == 0:
enc_init_enab = self.enc_init_contexts(level)
else: # level > 0:
enc_init_enab = self.enc_not_allowed_contexts(level)
#encInitEnab = simplify(Or(And(self.vInit[level], self.encInitContexts(level)),
# And(Not(self.vInit[level]), self.encNotAllowedContexts(level))))
enc_trans = simplify(And(enc_trans, enc_init_enab))
return enc_trans
def enc_state(self, level, state):
"""Encodes the state at the given level"""
enc = Not(self.v_init[level])
state_ids = self.reaction_system.get_state_ids(state)
for entity in state_ids:
enc = And(enc, self.v[level][entity])
not_in_state = set(range(0, len(self.reaction_system.background_set)))
not_in_state = not_in_state.difference(set(state_ids))
for entity in not_in_state:
enc = And(enc, Not(self.v[level][entity]))
return enc
def decode_witness(self, max_level):
m = self.solver.model()
for level in range(0,max_level+1):
print("\n[Level=" + repr(level) + "]")
if repr(m[self.v_init[level]]) == "True":
print("** Initial state")
print("State:\n{"),
for var_id in range(0, len(self.v[level])):
if repr(m[self.v[level][var_id]]) == "True":
print("\t" + self.reaction_system.get_entity_name(var_id)),
print("}")
if level != max_level:
print("Context set:"),
print("{"),
for var_id in range(0, len(self.v[level])):
if repr(m[self.v_ctx[level][var_id]]) == "True":
print("\t" + self.reaction_system.get_entity_name(var_id)),
print("}")
def check_reachability(self, state, print_witness=True, print_time=False):
"""Main testing function"""
if print_time:
start = time()
self.prepare_all_variables()
self.solver.add(self.enc_init_state(0))
current_level = 0
while True:
#print("Level: " + str(current_level))
print("\rLevel: " + str(current_level)),
stdout.flush()
self.prepare_all_variables()
# reachability test:
self.solver.push()
self.solver.add(self.enc_state(current_level,state))
result = self.solver.check()
print(result)
if result == sat:
print("\nSAT")
if print_witness:
self.decode_witness(current_level)
break
else:
self.solver.pop()
self.solver.add(self.enc_transition_relation(current_level))
current_level += 1
if print_time:
stop = time()
print("Time: " + repr(stop-start))
class SmtCheckerPGRS(object):
def __init__(self, rs):
##############################################################
# Encoded RS
##############################################################
rs.sanity_check()
self.reaction_system = rs
##############################################################
# SMT variables
##############################################################
self.v = []
self.v_init = []
#self.vSucc = []
#self.vSuccInit = []
self.v_ctx = []
self.next_level_to_encode = 0
##############################################################
# SMT solver instance
##############################################################
self.solver = Solver()
#def smtVar(self, level, entityID, primed=False):
# return "?"
def prepare_context_variables(self):
"""Encodes all the context variables"""
level = self.next_level_to_encode
variables = []
for entity in self.reaction_system.background_set:
variables.append(Bool("C"+str(level)+"_"+entity))
self.v_ctx.append(variables)
def prepare_state_variables(self):
"""Encodes all the state variables (including successors)"""
level = self.next_level_to_encode
variables = []
#variablesSucc = []
for entity in self.reaction_system.background_set:
variables.append(Bool("L"+str(level)+"_"+entity))
#variablesSucc.append(Bool("R"+str(level)+"_"+entity))
self.v.append(variables)
#self.vSucc.append(variablesSucc)
self.v_init.append(Bool("L"+str(level)+"_Init"))
#self.vSuccInit.append(Bool("R"+str(level)+"_Init"))
def prepare_all_variables(self):
"""Encodes all the variables"""
self.prepare_state_variables()
self.prepare_context_variables()
self.next_level_to_encode += 1
def enc_init_state(self, level):
"""Encodes the initial state at the given level"""
init_state_enc = self.v_init[level]
for v in self.v[level]:
init_state_enc = simplify(And(init_state_enc, Not(v)))
return init_state_enc
def enc_init_contexts(self, level):
"""Encodes the initial contexts set at the given level"""
init_contexts_set_enc = False # Or
for ctx in self.reaction_system.init_contexts:
single_ctx_enc = True # And
not_ctx_entities = list(range(0, len(self.reaction_system.background_set)))
for entity in ctx:
single_ctx_enc = simplify(And(single_ctx_enc, self.v_ctx[level][entity]))
not_ctx_entities.remove(entity)
for entity in not_ctx_entities:
single_ctx_enc = simplify(And(single_ctx_enc, Not(self.v_ctx[level][entity])))
init_contexts_set_enc = simplify(Or(init_contexts_set_enc, single_ctx_enc))
#print("initContextSetEnc: " + repr(initContextsSetEnc))
return init_contexts_set_enc
def enc_not_allowed_contexts(self, level):
"""Encodes all the context entities that are not allowed in the context sets"""
bg_set = set(range(0,len(self.reaction_system.background_set)))
ctx_ent_set = set(self.reaction_system.context_entities)
not_ctx_ent_set = bg_set.difference(ctx_ent_set)
enc = True
for entity in not_ctx_ent_set:
enc = simplify(And(enc, Not(self.v_ctx[level][entity])))
return enc
def enc_enabledness(self, level, prod_entity):
"""Encodes the enabledness condition for a given level and a given entity"""
rcts_for_prod_entity = self.reaction_system.get_reactions_by_product()[prod_entity]
if rcts_for_prod_entity == []:
return False
#encInitEnab = simplify(Or(And(self.vInit[level], self.encInitContexts(level)),
# And(Not(self.vInit[level]), self.encNotAllowedContexts(level))))
enc_rct_prod = False
for ri_pair in rcts_for_prod_entity: # reactants-inhibitors pair
enc_reactants = True
enc_inhibitors = True
for reactant in ri_pair[0]:
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][reactant], self.v_ctx[level][reactant])))
for inhibitor in ri_pair[1]:
enc_inhibitors = simplify(And(enc_inhibitors,
Not(Or(self.v[level][inhibitor], self.v_ctx[level][inhibitor]))))
enc_rct_prod = simplify(Or(enc_rct_prod, And(enc_reactants, enc_inhibitors)))
#print("encEnabledness(" + repr(prodEntity) + "): " + repr(simplify(And(encInitEnab, encRctProd))))
#return simplify(And(encInitEnab, encRctProd))
return enc_rct_prod
def enc_entity_production(self, level, prod_entity):
"""Encodes the production of a given entity from a given level at level+1"""
enc_enab_cond = self.enc_enabledness(level, prod_entity)
enc_ent_prod = Or(And(enc_enab_cond, self.v[level+1][prod_entity]),
And(Not(enc_enab_cond), Not(self.v[level+1][prod_entity])))
return enc_ent_prod
def enc_transition_relation(self, level):
"""Encodes the transition relation"""
unused_entities = list(range(0,len(self.reaction_system.background_set)))
enc_trans = True
for prod_entity in self.reaction_system.get_reactions_by_product():
unused_entities.remove(prod_entity)
enc_trans = simplify(And(enc_trans, self.enc_entity_production(level, prod_entity)))
enc_trans = simplify(And(enc_trans, Not(self.v_init[level+1])))
for prod_entity in unused_entities:
enc_trans = simplify(And(enc_trans, Not(self.v[level+1][prod_entity])))
if level == 0:
enc_init_enab = self.enc_init_contexts(level)
else: # level > 0:
enc_init_enab = self.enc_not_allowed_contexts(level)
#encInitEnab = simplify(Or(And(self.vInit[level], self.encInitContexts(level)),
# And(Not(self.vInit[level]), self.encNotAllowedContexts(level))))
enc_trans = simplify(And(enc_trans, enc_init_enab))
return enc_trans
def enc_state(self, level, state):
"""Encodes the state at the given level"""
enc = Not(self.v_init[level])
state_ids = self.reaction_system.get_state_ids(state)
for entity in state_ids:
enc = And(enc, self.v[level][entity])
not_in_state = set(range(0, len(self.reaction_system.background_set)))
not_in_state = not_in_state.difference(set(state_ids))
for entity in not_in_state:
enc = And(enc, Not(self.v[level][entity]))
return enc
def decode_witness(self, max_level):
m = self.solver.model()
for level in range(0,max_level+1):
print("\n[Level=" + repr(level) + "]")
if repr(m[self.v_init[level]]) == "True":
print("** Initial state")
print("State:\n{"),
for var_id in range(0, len(self.v[level])):
if repr(m[self.v[level][var_id]]) == "True":
print("\t" + self.reaction_system.get_entity_name(var_id)),
print("}")
if level != max_level:
print("Context set:"),
print("{"),
for var_id in range(0, len(self.v[level])):
if repr(m[self.v_ctx[level][var_id]]) == "True":
print("\t" + self.reaction_system.get_entity_name(var_id)),
print("}")
def check_reachability(self, state, print_witness=True, print_time=False):
"""Main testing function"""
if print_time:
start = time()
self.prepare_all_variables()
self.solver.add(self.enc_init_state(0))
current_level = 0
while True:
#print("Level: " + str(current_level))
print("\rLevel: " + str(current_level)),
stdout.flush()
self.prepare_all_variables()
# reachability test:
self.solver.push()
self.solver.add(self.enc_state(current_level,state))
result = self.solver.check()
print(result)
if result == sat:
print("\nSAT")
if print_witness:
self.decode_witness(current_level)
break
else:
self.solver.pop()
self.solver.add(self.enc_transition_relation(current_level))
current_level += 1
if print_time:
stop = time()
print("Time: " + repr(stop-start))

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@@ -1,432 +0,0 @@
"""
SMT-based Model Checking Module for RS with Context Automaton
"""
from z3 import *
from time import time,sleep
from sys import stdout
import resource
# def simplify(x):
# return x
class SmtCheckerDistribRS(object):
def __init__(self, drs, debug_level=1):
print("[i] Initialising the SMT module")
drs.sanity_check()
self.solver = Solver()
self.debug_level = debug_level
self.drs = drs
self.n_components = self.drs.components_count
# encoding variables
self.v = [] # level -> component -> variables
self.v_ctx = []
self.v_act = [] # indicators of which component is active
self.ca_state = []
self.level_to_encode = 0
def prepare_all_variables(self):
"""Encodes the required variables"""
self.prepare_state_variables()
self.prepare_context_variables()
self.prepare_activity_variables()
self.level_to_encode += 1 # prepare for the next invocation
def prepare_context_variables(self):
"""Encodes the context variables"""
level = self.level_to_encode
if self.debug_level > 1:
print("[ii] Preparing context variables for level=" + str(level))
level_variables = []
for i in range(self.n_components):
comp_variables = []
for entity in self.drs.background_set:
comp_variables.append(Bool("Ctx"+str(level)+"V"+str(i)+"_"+entity))
level_variables.append(comp_variables)
self.v_ctx.append(level_variables)
def prepare_activity_variables(self):
"""Encodes the activity variables"""
level = self.level_to_encode
if self.debug_level > 1:
print("[ii] Preparing activity variables for level=" + str(level))
level_variables = []
for i in range(self.n_components):
# L - level, A - activity indicator
level_variables.append(Bool("L"+str(level)+"A"+str(i)))
self.v_act.append(level_variables)
def prepare_state_variables(self):
"""Encodes all the state variables"""
level = self.level_to_encode
if self.debug_level > 1:
print("[ii] Preparing state variables for level=" + str(level))
level_variables = [] # level vars
for i in range(self.n_components):
comp_variables = []
for entity in self.drs.background_set:
# L - level, V - component
comp_variables.append(Bool("L"+str(level)+"V"+str(i)+"_"+entity))
level_variables.append(comp_variables)
self.v.append(level_variables)
# single state variable for CA
self.ca_state.append(Int("CA"+str(level)+"_state"))
def enc_init_state(self, level):
"""Encodes the initial state at the given level"""
if self.debug_level > 1:
print("[ii] Encoding the initial state for level=" + str(level))
rs_init_state_enc = True
for i in range(self.n_components):
for v in self.v[level][i]:
rs_init_state_enc = simplify(And(rs_init_state_enc, Not(v))) # the initial state is empty
ca_init_state_enc = self.ca_state[level] == self.drs.get_init_state_id()
init_state_enc = simplify(And(rs_init_state_enc, ca_init_state_enc))
# print ("init_state_enc:\n", init_state_enc)
return init_state_enc
def enc_enabledness(self, level, prod_entity, component_id):
"""Encodes the enabledness condition for a given level and a given entity"""
rcts_for_prod_entity = self.drs.get_reactions_by_product(component_id)[prod_entity]
if rcts_for_prod_entity == []:
return False
enc_rct_prod = False
for reactants,inhibitors in rcts_for_prod_entity:
enc_reactants = True
for reactant in reactants:
enc_active_reactants = False
for i in range(self.n_components):
enc_active_reactants = simplify(Or(enc_active_reactants,
And( Or(self.v[level][i][reactant], self.v_ctx[level][i][reactant]), self.v_act[level][i] )))
enc_reactants = And(enc_reactants, enc_active_reactants)
enc_inhibitors = True
for inhibitor in inhibitors:
enc_active_inhibitors = True
for i in range(self.n_components):
enc_active_inhibitors = simplify(And(enc_active_inhibitors,
And(
Or( And(Not(self.v[level][i][inhibitor]), Not(self.v_ctx[level][i][inhibitor])), Not(self.v_act[level][i]) )
)))
enc_inhibitors = simplify(And(enc_inhibitors, enc_active_inhibitors))
# print("--> enc_inhibitors\n", enc_inhibitors)
enc_rct_prod = Or(enc_rct_prod, And(enc_reactants, enc_inhibitors))
# print("enc_rct_prod:\n", enc_rct_prod)
enc_rct_prod = simplify(enc_rct_prod)
return enc_rct_prod
def enc_entity_production(self, level, prod_entity, component_id):
"""Encodes the production of a given entity at level+1 from a given level"""
enc_enab_cond = self.enc_enabledness(level, prod_entity, component_id)
enc_base_ent_prod = simplify(Or(And(enc_enab_cond, self.v[level+1][component_id][prod_entity]),
And(Not(enc_enab_cond), Not(self.v[level+1][component_id][prod_entity]))))
enc_active_ent_prod = simplify(And(self.v_act[level][component_id], enc_base_ent_prod))
enc_inactive_ent_prod = simplify(And(
Not(self.v_act[level][component_id]),
self.v[level][component_id][prod_entity] == self.v[level+1][component_id][prod_entity]))
enc_ent_prod = Or(enc_active_ent_prod, enc_inactive_ent_prod)
# print("enc_ent_prod:\n", enc_ent_prod)
return simplify(enc_ent_prod)
def enc_rs_trans(self, level):
"""Encodes the transition relation"""
enc_trans = True
for component_id in range(self.n_components):
print("\rEncoding for reactions: %d/%d" % (component_id,self.n_components-1), flush=True, end="")
unused_entities = list(range(len(self.drs.background_set)))
for prod_entity in self.drs.get_reactions_by_product(component_id):
unused_entities.remove(prod_entity)
enc_trans = simplify(And(enc_trans, self.enc_entity_production(level, prod_entity, component_id)))
for prod_entity in unused_entities:
enc_trans = simplify(And(enc_trans, Not(self.v[level+1][component_id][prod_entity])))
print()
# print("enc_rs_trans:\n", enc_trans)
enc_trans = simplify(enc_trans)
return enc_trans
def enc_automaton_trans(self, level):
"""Encodes the transition relation for the context automaton"""
enc_trans = False
i = 0
for src,(components,ctx_set),dst in self.drs.transitions:
src_enc = self.ca_state[level] == src
dst_enc = self.ca_state[level+1] == dst
print("\rEncoding for context automaton: %d/%d" % (i,len(self.drs.transitions)-1), flush=True, end="")
i = i + 1
# contexts {
ctx_set_enc = True
for comp_id in range(self.n_components):
all_ent = set(range(len(self.drs.background_set)))
incl_ctx = ctx_set[comp_id]
excl_ctx = all_ent - incl_ctx
ctx_enc = True
for c in incl_ctx:
ctx_enc = And(ctx_enc, self.v_ctx[level][comp_id][c])
for c in excl_ctx:
ctx_enc = And(ctx_enc, Not(self.v_ctx[level][comp_id][c]))
ctx_set_enc = And(ctx_set_enc, ctx_enc)
# } contexts
# active components {
all_active = set(range(self.n_components))
incl_comp = components
excl_comp = all_active - incl_comp
active_components_enc = True
for comp_id in incl_comp:
active_components_enc = And(active_components_enc, self.v_act[level][comp_id])
for comp_id in excl_comp:
active_components_enc = And(active_components_enc, Not(self.v_act[level][comp_id]))
# } active components
cur_trans = And(src_enc, ctx_set_enc, active_components_enc, dst_enc)
enc_trans = Or(enc_trans, cur_trans)
print()
enc_trans = simplify(enc_trans)
# print("enc_automaton_trans:\n", enc_trans)
return enc_trans
def enc_transition_relation(self, level):
rs_enc = self.enc_rs_trans(level)
aut_enc = self.enc_automaton_trans(level)
print("Conjunction...", flush=True, end="")
c = simplify(And(rs_enc, aut_enc))
print("done.")
return c
def enc_state(self, level, global_state):
"""Encodes the state at the given level"""
if len(global_state) != self.n_components:
print("EEE: Wrong size of the global state! " + "(is " + str(len(global_state)) + ", should be " + str(self.n_components) + ")")
exit(1)
enc = True
if self.debug_level > 2:
print("[iii] Encoding exclusive/exact global state " + str(global_state) + " for level=" + str(level))
for i in range(self.n_components):
local_state = global_state[i]
local_state_ids = self.drs.get_state_ids(local_state)
for entity in local_state_ids:
enc = And(enc, self.v[level][i][entity])
not_in_state = self.drs.set_of_background_ids - set(local_state_ids)
for e_id in not_in_state:
enc = simplify(And(enc, Not(self.v[level][i][e_id])))
simplify(enc)
# print("state:\n", enc)
return enc
def enc_inclusive_state(self, level, global_state):
"""Encodes the state at the given level"""
if len(global_state) != self.n_components:
print("EEE: Wrong size of the global state! " + "(is " + str(len(global_state)) + ", should be " + str(self.n_components) + ")")
exit(1)
enc = True
if self.debug_level > 2:
print("[iii] Encoding inclusive/general global state " + str(global_state) + " for level=" + str(level))
for i in range(self.n_components):
local_state = global_state[i]
local_state_ids = self.drs.get_state_ids(local_state)
for entity in local_state_ids:
enc = And(enc, self.v[level][i][entity])
simplify(enc)
return enc
def decode_witness(self, max_level, print_model=False):
m = self.solver.model()
print("\nWitness:")
if print_model:
print(m)
for level in range(max_level+1):
print("\n[Level=" + repr(level) + "]")
#print(m)
#print(self.v[level][0][2])
#print(m[self.v[level][0][2]])
print(" State: {", end=""),
for c in range(self.n_components):
print(" <", end="")
for var_id in range(len(self.v[level][c])):
if repr(m[self.v[level][c][var_id]]) == "True":
print(" " + self.drs.get_entity_name(var_id), end="")
print(" >", end="")
print(" }")
if level != max_level:
print(" Context set: ", end="")
print("{", end="")
for c in range(self.n_components):
print(" <", end="")
for var_id in range(len(self.v[level][c])):
if repr(m[self.v_ctx[level][c][var_id]]) == "True":
print(" " + self.drs.get_entity_name(var_id), end="")
print(" >", end="")
print(" }")
print(" Active components:", end="")
for c in range(self.n_components):
if repr(m[self.v_act[level][c]]) == "True":
print(" " + str(c), end="")
print()
def check_reachability(self, state, exclusive_state=False, print_witness=True, print_time=False, print_mem=False, max_level=100):
"""Reachability checking"""
print("[i] Checking reachability...")
if print_time:
start = time()
self.prepare_all_variables()
self.solver.add(self.enc_init_state(0))
current_level = 0
while True:
self.prepare_all_variables()
print("-----[ Working at level=" + str(current_level) + " ]-----")
stdout.flush()
# reachability test:
self.solver.push()
print("[i] Adding the reachability test...")
if exclusive_state == False:
self.solver.add(self.enc_inclusive_state(current_level,state))
else:
self.solver.add(self.enc_state(current_level,state))
result = self.solver.check()
if result == sat:
print("\n[+] SAT at level=" + str(current_level))
if print_witness:
self.decode_witness(current_level)
break
else:
self.solver.pop()
print("[i] Unrolling the transition relation")
self.solver.add(self.enc_transition_relation(current_level))
print("-----[ level=" + str(current_level) + " done ]")
current_level += 1
if current_level > max_level:
print("Stopping at level=" + str(max_level))
break
if print_time:
stop = time()
print()
print("==== Time: " + repr(stop-start))
if print_mem:
usage=resource.getrusage(resource.RUSAGE_SELF)
print("MEM: usertime=%s systime=%s mem=%sMB" % (usage[0],usage[1], (resource.getrusage(resource.RUSAGE_SELF).ru_maxrss / 1024**2)))

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@@ -1,275 +0,0 @@
"""
SMT-based Model Checking Module for RS with Context Automaton
"""
from z3 import *
from time import time
from sys import stdout
import resource
class SmtCheckerPGRS(object):
def __init__(self, rsca):
rsca.sanity_check()
self.rs = rsca.rs
self.ca = rsca.ca
self.v = []
self.v_ctx = []
self.ca_state = []
self.next_level_to_encode = 0
self.solver = Solver()
self.verification_time = None
def prepare_all_variables(self):
"""Encodes all the variables"""
self.prepare_state_variables()
self.prepare_context_variables()
self.next_level_to_encode += 1
def prepare_context_variables(self):
"""Encodes all the context variables"""
level = self.next_level_to_encode
variables = []
for entity in self.rs.background_set:
variables.append(Bool("C"+str(level)+"_"+entity))
self.v_ctx.append(variables)
def prepare_state_variables(self):
"""Encodes all the state variables"""
level = self.next_level_to_encode
variables = []
for entity in self.rs.background_set:
variables.append(Bool("L"+str(level)+"_"+entity))
self.v.append(variables)
self.ca_state.append(Int("CA"+str(level)+"_state"))
def enc_init_state(self, level):
"""Encodes the initial state at the given level"""
rs_init_state_enc = True
for v in self.v[level]:
rs_init_state_enc = simplify(And(rs_init_state_enc, Not(v))) # the initial state is empty
ca_init_state_enc = self.ca_state[level] == self.ca.get_init_state_id()
init_state_enc = simplify(And(rs_init_state_enc, ca_init_state_enc))
return init_state_enc
def enc_enabledness(self, level, prod_entity):
"""Encodes the enabledness condition for a given level and a given entity"""
rcts_for_prod_entity = self.rs.get_reactions_by_product()[prod_entity]
if rcts_for_prod_entity == []:
return False
enc_rct_prod = False
for reactants,inhibitors in rcts_for_prod_entity:
enc_reactants = True
enc_inhibitors = True
for reactant in reactants:
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][reactant], self.v_ctx[level][reactant])))
for inhibitor in inhibitors:
enc_inhibitors = simplify(And(enc_inhibitors,
Not(Or(self.v[level][inhibitor], self.v_ctx[level][inhibitor]))))
enc_rct_prod = simplify(Or(enc_rct_prod, And(enc_reactants, enc_inhibitors)))
return enc_rct_prod
def enc_entity_production(self, level, prod_entity):
"""Encodes the production of a given entity from a given level at level+1"""
enc_enab_cond = self.enc_enabledness(level, prod_entity)
enc_ent_prod = Or(And(enc_enab_cond, self.v[level+1][prod_entity]),
And(Not(enc_enab_cond), Not(self.v[level+1][prod_entity])))
return simplify(enc_ent_prod)
def enc_transition_relation(self, level):
return simplify(And(self.enc_rs_trans(level), self.enc_automaton_trans(level)))
def enc_rs_trans(self, level):
"""Encodes the transition relation"""
unused_entities = list(range(len(self.rs.background_set)))
enc_trans = True
for prod_entity in self.rs.get_reactions_by_product():
unused_entities.remove(prod_entity)
enc_trans = simplify(And(enc_trans, self.enc_entity_production(level, prod_entity)))
for prod_entity in unused_entities:
enc_trans = simplify(And(enc_trans, Not(self.v[level+1][prod_entity])))
return enc_trans
def enc_automaton_trans(self, level):
"""Encodes the transition relation for the context automaton"""
enc_trans = False
for src,ctx,dst in self.ca.transitions:
src_enc = self.ca_state[level] == src
dst_enc = self.ca_state[level+1] == dst
all_ent = set(range(len(self.rs.background_set)))
incl_ctx = ctx
excl_ctx = all_ent - incl_ctx
ctx_enc = True
for c in incl_ctx:
ctx_enc = simplify(And(ctx_enc, self.v_ctx[level][c]))
for c in excl_ctx:
ctx_enc = simplify(And(ctx_enc, Not(self.v_ctx[level][c])))
cur_trans = simplify(And(src_enc, ctx_enc, dst_enc))
enc_trans = simplify(Or(enc_trans, cur_trans))
return enc_trans
def enc_state(self, level, state):
"""Encodes the state at the given level"""
enc = True
state_ids = self.rs.get_state_ids(state)
for entity in state_ids:
enc = And(enc, self.v[level][entity])
not_in_state = set(range(len(self.rs.background_set)))
not_in_state = not_in_state.difference(set(state_ids))
for entity in not_in_state:
enc = And(enc, Not(self.v[level][entity]))
return enc
def enc_non_exclusive_state(self, level, state):
"""Encodes the state at the given level"""
enc = True
state_ids = self.rs.get_state_ids(state)
for entity in state_ids:
enc = And(enc, self.v[level][entity])
return enc
def enc_state_with_blocking(self, level, prop):
"""Encodes the state at the given level with blocking certain concentrations"""
required,blocked = prop
enc = True
required_ids = self.rs.get_state_ids(required)
blocked_ids = self.rs.get_state_ids(blocked)
for e in required_ids:
enc = And(enc, self.v[level][e])
for e in blocked_ids:
enc = And(enc, Not(self.v[level][e]))
return simplify(enc)
def decode_witness(self, max_level, print_model=False):
m = self.solver.model()
if print_model:
print(m)
for level in range(max_level+1):
print("\n[Level=" + repr(level) + "]")
print(" State: {", end=""),
for var_id in range(len(self.v[level])):
if repr(m[self.v[level][var_id]]) == "True":
print(" " + self.rs.get_entity_name(var_id), end="")
print(" }")
if level != max_level:
print(" Context set: ", end="")
print("{", end="")
for var_id in range(len(self.v[level])):
if repr(m[self.v_ctx[level][var_id]]) == "True":
print(" " + self.rs.get_entity_name(var_id), end="")
print(" }")
def check_reachability(self, state, print_witness=True, print_time=True, print_mem=True):
"""Main testing function"""
if not type(state) is tuple:
state = (state,[])
if print_time:
# start = time()
start = resource.getrusage(resource.RUSAGE_SELF).ru_utime
self.prepare_all_variables()
self.solver.add(self.enc_init_state(0))
current_level = 0
while True:
print("-----[ Working at level=" + str(current_level) + " ]-----")
stdout.flush()
self.prepare_all_variables()
# reachability test:
print("[i] Adding the reachability test...")
self.solver.push()
self.solver.add(self.enc_state_with_blocking(current_level,state))
result = self.solver.check()
if result == sat:
print("\n[+] SAT at level=" + str(current_level))
if print_witness:
self.decode_witness(current_level)
break
else:
self.solver.pop()
print("[i] Unrolling the transition relation")
self.solver.add(self.enc_transition_relation(current_level))
print("-----[ level=" + str(current_level) + " done ]")
current_level += 1
if print_time:
# stop = time()
stop = resource.getrusage(resource.RUSAGE_SELF).ru_utime
self.verification_time = stop-start
print()
print("[i] Time: " + repr(self.verification_time))
if print_mem:
print("[i] Memory: " + repr(resource.getrusage(resource.RUSAGE_SELF).ru_maxrss/(1024*1024)) + " MB")
def get_verification_time(self):
return self.verification_time

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@@ -1,480 +0,0 @@
"""
SMT-based Model Checking Module for RS with Concentrations and Context Automaton
"""
from z3 import *
from time import time
from sys import stdout
from itertools import chain
import resource
from colour import *
# def simplify(x):
# return x
class SmtCheckerRSC(object):
def __init__(self, rsca):
rsca.sanity_check()
if not rsca.is_with_concentrations():
raise RuntimeError("RS and CA with concentrations expected")
self.rs = rsca.rs
self.ca = rsca.ca
self.v = []
self.v_ctx = []
self.ca_state = []
self.next_level_to_encode = 0
self.solver = Solver()
self.verification_time = None
def prepare_all_variables(self):
"""Encodes all the variables"""
self.prepare_state_variables()
self.prepare_context_variables()
self.next_level_to_encode += 1
def prepare_context_variables(self):
"""Encodes all the context variables"""
level = self.next_level_to_encode
variables = []
for entity in self.rs.background_set:
variables.append(Int("C"+str(level)+"_"+entity))
self.v_ctx.append(variables)
def prepare_state_variables(self):
"""Encodes all the state variables"""
level = self.next_level_to_encode
variables = []
for entity in self.rs.background_set:
variables.append(Int("L"+str(level)+"_"+entity))
self.v.append(variables)
self.ca_state.append(Int("CA"+str(level)+"_state"))
def enc_concentration_levels_assertion(self, level):
"""Encodes assertions that (some) variables need to be >0
We do not need to actually control all the variables,
only those that can possibly go below 0.
"""
enc_nz = True
for e_i in range(len(self.rs.background_set)):
v = self.v[level][e_i]
v_ctx = self.v_ctx[level][e_i]
e_max = self.rs.get_max_concentration_level(e_i)
enc_nz = simplify(And(enc_nz, v >= 0, v_ctx >= 0, v <= e_max, v_ctx <= e_max))
return enc_nz
def enc_init_state(self, level):
"""Encodes the initial state at the given level"""
rs_init_state_enc = True
for v in self.v[level]:
rs_init_state_enc = simplify(And(rs_init_state_enc, v == 0)) # the initial concentration levels are zeroed
ca_init_state_enc = self.ca_state[level] == self.ca.get_init_state_id()
init_state_enc = simplify(And(rs_init_state_enc, ca_init_state_enc))
return init_state_enc
def enc_produced_concentration(self, level, prod_entity):
"""Encodes the produced concentrations for the given level and entity"""
rcts_for_prod_entity = []
if prod_entity in self.rs.get_reactions_by_product():
rcts_for_prod_entity = self.rs.get_reactions_by_product()[prod_entity]
meta_reactions = []
if prod_entity in self.rs.meta_reactions:
meta_reactions = self.rs.meta_reactions[prod_entity]
permanency_inhibition = None
if prod_entity in self.rs.permanent_entities:
permanency_inhibition = self.rs.permanent_entities[prod_entity]
if rcts_for_prod_entity == [] and meta_reactions == []:
return simplify(self.v[level+1][prod_entity] == 0) # this should never happen
enc_enabledness = False
# ----------- ordinary reactions --------------------------------------------
enc_rct_prod = False
enc_ordinary_reactions_enabledness = False
for reactants,inhibitors,products in rcts_for_prod_entity:
enc_reactants = True
for reactant,concentration in reactants:
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][reactant] >= concentration, self.v_ctx[level][reactant] >= concentration)))
enc_inhibitors = True
for inhibitor,concentration in inhibitors:
enc_inhibitors = simplify(And(enc_inhibitors,
And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
enc_rct_enabled = And(enc_reactants, enc_inhibitors)
enc_products = self.v[level+1][products[0][0]] == products[0][1]
enc_rct_prod = simplify(If(enc_rct_enabled, enc_products, enc_rct_prod))
enc_enabledness = simplify(Or(enc_enabledness, enc_rct_enabled))
enc_ordinary_reactions_enabledness = simplify(Or(enc_ordinary_reactions_enabledness,enc_rct_enabled))
# for reactants,inhibitors,products in rcts_for_prod_entity:
# enc_reactants = True
# enc_inhibitors = True
# # enc_products -- below
#
# for reactant,concentration in reactants:
# enc_reactants = simplify(And(enc_reactants,
# Or(self.v[level][reactant] >= concentration, self.v_ctx[level][reactant] >= concentration)))
# for inhibitor,concentration in inhibitors:
# enc_inhibitors = simplify(And(enc_inhibitors,
# And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
#
# enc_products = self.v[level+1][products[0][0]] == products[0][1]
#
# enc_enabledness = simplify(Or(enc_enabledness, And(enc_reactants, enc_inhibitors)))
# enc_rct_prod = simplify(Or(enc_rct_prod, And(enc_reactants, enc_inhibitors, enc_products)))
# -------- meta reactions ---------------------------------------------------
for r_type,command_entity,reactants,inhibitors in meta_reactions:
# command entity is e.g. 'inc' for incrementation operation
# (inc,W) gives us the value W by which the given entity's value should be incremented
enc_reactants = True
enc_inhibitors = True
for reactant,concentration in reactants:
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][reactant] >= concentration, self.v_ctx[level][reactant] >= concentration)))
# command entity needs to be present (with concentration level > 0) in order to perform the operation
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][command_entity] > 0, self.v_ctx[level][command_entity] > 0)))
for inhibitor,concentration in inhibitors:
enc_inhibitors = simplify(And(enc_inhibitors,
And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
if r_type == "inc":
value_after_inc = If(self.v[level][prod_entity]>self.v_ctx[level][prod_entity],self.v[level][prod_entity],self.v_ctx[level][prod_entity]) + \
If(self.v[level][command_entity]>self.v_ctx[level][command_entity],self.v[level][command_entity],self.v_ctx[level][command_entity])
enc_products = self.v[level+1][prod_entity] == value_after_inc
elif r_type == "dec":
value_after_dec = simplify(If(self.v[level][prod_entity]>self.v_ctx[level][prod_entity],self.v[level][prod_entity],self.v_ctx[level][prod_entity]) - \
If(self.v[level][command_entity]>self.v_ctx[level][command_entity],self.v[level][command_entity],self.v_ctx[level][command_entity]))
enc_products = self.v[level+1][prod_entity] == If(value_after_dec < 0, 0, value_after_dec)
else:
raise RuntimeError("Unknown meta-reaction type: " + repr(r_type))
enc_meta_reaction_enabledness = And(enc_reactants, enc_inhibitors, Not(enc_ordinary_reactions_enabledness))
enc_enabledness = simplify(Or(enc_enabledness, enc_meta_reaction_enabledness))
enc_rct_prod = simplify(Or(enc_rct_prod, And(enc_meta_reaction_enabledness, enc_products)))
# -----------------------------------------------------------------------------
if not permanency_inhibition == None:
enc_reactants = Or(self.v[level][prod_entity] >= concentration, self.v_ctx[level][prod_entity] >= concentration)
enc_inhibitors = True
for inhibitor,concentration in permanency_inhibition:
enc_inhibitors = simplify(And(enc_inhibitors,
And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
enc_products = simplify(self.v[level+1][prod_entity] == \
If(self.v[level][prod_entity] > self.v_ctx[level][prod_entity],self.v[level][prod_entity],self.v_ctx[level][prod_entity]))
enc_permanency_enabledness = And(enc_reactants, enc_inhibitors, Not(enc_ordinary_reactions_enabledness))
enc_enabledness = simplify(Or(enc_enabledness, enc_permanency_enabledness))
enc_permanency = And(enc_permanency_enabledness, enc_products)
enc_rct_prod = simplify(Or(enc_rct_prod, enc_permanency))
# -----------------------------------------------------------------------------
enc_when_to_produce_zero_conc = simplify(And(Not(enc_enabledness), self.v[level+1][prod_entity] == 0))
enc_rct_prod = Or(enc_rct_prod, enc_when_to_produce_zero_conc)
return enc_rct_prod
# def enc_entity_production(self, level, prod_entity):
# """Encodes the production of a given entity from a given level at level+1"""
#
# enc_enab_cond = self.enc_enabledness(level, prod_entity)
#
# enc_ent_prod = Or(And(enc_enab_cond, self.v[level+1][prod_entity]),
# And(Not(enc_enab_cond), Not(self.v[level+1][prod_entity])))
#
# return simplify(enc_ent_prod)
def enc_transition_relation(self, level):
return simplify(And(self.enc_rs_trans(level), self.enc_automaton_trans(level)))
def enc_rs_trans(self, level):
"""Encodes the transition relation"""
unused_entities = set(range(len(self.rs.background_set)))
enc_trans = True
reactions = self.rs.get_reactions_by_product()
meta_reactions = self.rs.meta_reactions
for prod_entity in chain(reactions, meta_reactions):
unused_entities.discard(prod_entity)
enc_trans = simplify(And(enc_trans, self.enc_produced_concentration(level, prod_entity)))
for prod_entity in unused_entities:
enc_trans = simplify(And(enc_trans, self.v[level+1][prod_entity] == 0))
return enc_trans
def enc_automaton_trans(self, level):
"""Encodes the transition relation for the context automaton"""
enc_trans = False
for src,ctx,dst in self.ca.transitions:
src_enc = self.ca_state[level] == src
dst_enc = self.ca_state[level+1] == dst
all_ent = set(range(len(self.rs.background_set)))
incl_ctx = set([e for e,c in ctx])
excl_ctx = all_ent - incl_ctx
ctx_enc = True
for e,c in ctx:
ctx_enc = simplify(And(ctx_enc, self.v_ctx[level][e] == c))
for e in excl_ctx:
ctx_enc = simplify(And(ctx_enc, self.v_ctx[level][e] == 0))
cur_trans = simplify(And(src_enc, ctx_enc, dst_enc))
enc_trans = simplify(Or(enc_trans, cur_trans))
return enc_trans
def enc_exact_state(self, level, state):
"""Encodes the state at the given level with the exact concentration values"""
raise RuntimeError("Should not be used with RSC")
# enc = True
# used_entities_ids = self.rs.get_state_ids(state)
#
# for ent,conc in state:
# e_id = self.rs.get_entity_id(ent)
# enc = And(enc, self.v[level][e_id] == conc)
#
# not_in_state = set(range(len(self.rs.background_set)))
# not_in_state = not_in_state.difference(set(used_entities_ids))
#
# for entity in not_in_state:
# enc = And(enc, self.v[level][entity] == 0)
#
# return simplify(enc)
def enc_min_state(self, level, state):
"""Encodes the state at the given level with the minimal required concentration levels"""
enc = True
for ent,conc in state:
e_id = self.rs.get_entity_id(ent)
enc = And(enc, self.v[level][e_id] >= conc)
# state_ids = self.rs.get_state_ids(state)
#
# for entity in state_ids:
# enc = And(enc, self.v[level][entity])
return simplify(enc)
def enc_state_with_blocking(self, level, prop):
"""Encodes the state at the given level with blocking certain concentrations"""
required,blocked = prop
enc = True
for ent,conc in required:
e_id = self.rs.get_entity_id(ent)
enc = And(enc, self.v[level][e_id] >= conc)
for ent,conc in blocked:
e_id = self.rs.get_entity_id(ent)
enc = And(enc, self.v[level][e_id] < conc)
return simplify(enc)
def decode_witness(self, max_level, print_model=False):
m = self.solver.model()
if print_model:
print(m)
for level in range(max_level+1):
print("\n{: >70}".format("[ level=" + repr(level) + " ]"))
print(" State: {", end=""),
for var_id in range(len(self.v[level])):
var_rep = repr(m[self.v[level][var_id]])
if not var_rep.isdigit():
raise RuntimeError("unexpected: representation is not a positive integer")
if int(var_rep) > 0:
print(" " + self.rs.get_entity_name(var_id) + "=" + var_rep, end="")
# print(" " + repr(m[self.v[level][var_id]]), end="")
print(" }")
if level != max_level:
print(" Context set: ", end="")
print("{", end="")
for var_id in range(len(self.v[level])):
var_rep = repr(m[self.v_ctx[level][var_id]])
if not var_rep.isdigit():
raise RuntimeError("unexpected: representation is not a positive integer")
if int(var_rep) > 0:
print(" " + self.rs.get_entity_name(var_id) + "=" + var_rep, end="")
print(" }")
def check_reachability(self, state, print_witness=True,
print_time=True, print_mem=True, max_level=100):
"""Main testing function"""
if print_time:
# start = time()
start = resource.getrusage(resource.RUSAGE_SELF).ru_utime
self.prepare_all_variables()
self.solver.add(self.enc_init_state(0))
current_level = 0
self.prepare_all_variables()
self.solver.add(self.enc_concentration_levels_assertion(0))
while True:
self.prepare_all_variables()
self.solver.add(self.enc_concentration_levels_assertion(current_level+1))
print("\n{:-^70}".format("[ Working at level=" + str(current_level) + " ]"))
stdout.flush()
# reachability test:
print("[" + colour_str(C_BOLD, "i") + "] Adding the reachability test...")
self.solver.push()
self.solver.add(self.enc_state_with_blocking(current_level,state))
result = self.solver.check()
if result == sat:
print("[" + colour_str(C_BOLD, "+") + "] " + colour_str(C_GREEN, "SAT at level=" + str(current_level)))
if print_witness:
print("\n{:=^70}".format("[ WITNESS ]"))
self.decode_witness(current_level)
break
else:
self.solver.pop()
print("[" + colour_str(C_BOLD, "i") + "] Unrolling the transition relation")
self.solver.add(self.enc_transition_relation(current_level))
print("{:->70}".format("[ level=" + str(current_level) + " done ]"))
current_level += 1
if current_level > max_level:
print("Stopping at level=" + str(max_level))
break
if print_time:
# stop = time()
stop = resource.getrusage(resource.RUSAGE_SELF).ru_utime
self.verification_time = stop-start
print()
print("\n[i] {: >60}".format(" Time: " + repr(self.verification_time) + " s"))
if print_mem:
print("[i] {: >60}".format(" Memory: " + repr(resource.getrusage(resource.RUSAGE_SELF).ru_maxrss/(1024*1024)) + " MB"))
def get_verification_time(self):
return self.verification_time
def show_encoding(self, state, print_witness=True,
print_time=False, print_mem=False, max_level=100):
"""Encoding debug function"""
self.prepare_all_variables()
init_s = self.enc_init_state(0)
print(init_s)
self.solver.add(init_s)
current_level = 0
self.prepare_all_variables()
while True:
self.prepare_all_variables()
print("-----[ Working at level=" + str(current_level) + " ]-----")
stdout.flush()
# reachability test:
print("[i] Adding the reachability test...")
self.solver.push()
s = self.enc_min_state(current_level,state)
print("Test: ", s)
self.solver.add(s)
result = self.solver.check()
if result == sat:
print("\n[+] " + colour_str(C_RED, "SAT at level=" + str(current_level)))
if print_witness:
self.decode_witness(current_level)
break
else:
self.solver.pop()
print("[i] Unrolling the transition relation")
t = self.enc_transition_relation(current_level)
print(t)
self.solver.add(t)
print("-----[ level=" + str(current_level) + " done ]")
current_level += 1
if current_level > max_level:
print("Stopping at level=" + str(max_level))
break
else:
x=input("Next level? ")
x=x.lower()
if not (x == "y" or x == "yes"):
break