def test_context(self):
     cfg = Config()
     ctx = Context(cfg)
     stat = ctx.status()
     ret = ctx.push()
     ret = ctx.pop()
     ctx.reset_context()
     ret = ctx.enable_option("arith-elim")
     ret = ctx.disable_option("arith-elim")
     stat = ctx.status()
     self.assertEqual(stat, 0)
     ctx.reset_context()
     bool_t = Types.bool_type()
     bvar1 = Terms.new_variable(bool_t)
     with assertRaisesRegex(self, YicesException,
                            'assertion contains a free variable'):
         ctx.assert_formula(bvar1)
     bv_t = Types.bv_type(3)
     bvvar1 = Terms.new_uninterpreted_term(bv_t, 'x')
     bvvar2 = Terms.new_uninterpreted_term(bv_t, 'y')
     bvvar3 = Terms.new_uninterpreted_term(bv_t, 'z')
     fmla1 = Terms.parse_term('(= x (bv-add y z))')
     fmla2 = Terms.parse_term('(bv-gt y 0b000)')
     fmla3 = Terms.parse_term('(bv-gt z 0b000)')
     ctx.assert_formula(fmla1)
     ctx.assert_formulas([fmla1, fmla2, fmla3])
     smt_stat = ctx.check_context(None)
     self.assertEqual(smt_stat, Status.SAT)
     ctx.assert_blocking_clause()
     ctx.stop_search()
     param = Parameters()
     param.default_params_for_context(ctx)
     param.set_param("dyn-ack", "true")
     with assertRaisesRegex(self, YicesException, 'invalid parameter'):
         param.set_param("foo", "bar")
     with assertRaisesRegex(self, YicesException,
                            'value not valid for parameter'):
         param.set_param("dyn-ack", "bar")
     param.dispose()
     ctx.dispose()
示例#2
0
class Solver(object):

    def __init__(self, diagram, protocol, verbose):
        self.diagram = diagram
        self.protocol = protocol
        self.verbose = verbose
        self.maxTimeStamp = diagram.max_timestamp
        print('Maximum time = {0}'.format(self.maxTimeStamp))
        self.context = Context()
        # assert that (b i) = b_i and (pt x y) = pt_x_y
        yassert_formulas(self, YicesSignature.toYicesTerms())


    def addFacts(self):
        if not self.addModel():
            return False
        self.protocol.constrainVariablesAPI(self.context)
        if not self.addProtocol():
            return False
        return True

    def addModel(self):
        # The last argument indicates that the theory should be completed.
        # Anything not asserted is asserted to be False.
        assertions = self.diagram.toYicesTerms(point=None, completeMe=True)
        if assertions is None:
            assertions = []
        retval =  yassert_formulas(self, assertions)
        if not retval:
            sys.stderr.write('addModel() failed\n')
        return retval

    def addProtocol(self):
        assertions = self.protocol.toYicesTerms(None, None, self.maxTimeStamp)
        if assertions is None:
            assertions = []
        retval = yassert_formulas(self, assertions)
        if not retval:
            sys.stderr.write('addProtocol() failed\n')
        return retval


    def getProtocolIncrementally(self, level):
        return self.protocol.toYicesTermsIncrementally(level)

    def writeTheory(self, theory_file):
        sb = StringBuffer()
        SymbolTable.toYices(sb)
        self.diagram.toYices(sb, None, True)
        self.protocol.toYices(sb, self.maxTimeStamp, False)
        theory = str(sb)
        string2File(theory, theory_file, False)
        string2File("(check)\n(show-model)\n", theory_file, True)



    def consistency_check(self):
        assertions = self.diagram.toYicesTerms(point=None, completeMe=True)
        alen = len(assertions)
        if alen:
            smt_stat = self.context.check_context_with_assumptions(None, assertions)
            sys.stderr.write('context.check_context_with_assumptions returned {0}\n'.format(Status.name(smt_stat)))
            if smt_stat == Status.SAT:
                #sys.stderr.write('Calling unsat_core on a satisfiable theory is user error\n')
                retcode = 0
            elif smt_stat == Status.UNSAT:
                unsat_core = self.context.get_unsat_core()
                if not unsat_core:
                    sys.stderr.write('unsat_core is empty\n')
                else:
                    print("\nUnsat core:\n")
                    for term in unsat_core:
                        Terms.print_to_fd(1, term, 80, 100, 0)
                    print("\n")
            else:
                retcode = 1
            retcode = 0
        self._cleanUp()
        return retcode


    # a retcode of 0 means the problem is SAT
    # a retcode of 1 means the problem is UNSAT
    # a retcode of 2 means there was an error somewhere
    def solve(self, theory_file):
        retcode = 2
        if not self.addFacts():
            return retcode
        if theory_file is not None:
            self.writeTheory(theory_file)
        smt_stat = self.context.check_context()
        if smt_stat != Status.SAT:
            print('No solution: smt_stat = {0}\n'.format(smt_stat))
            retcode = 1
        else:
            print('\nSatisfiable.')
            #get the model
            model = Model.from_context(self.context, 1)
            self.print_solution(model)
            model.dispose()
            retcode = 0
        self._cleanUp()
        return retcode




    def incrementally_solve(self):
        retcode = 2
        if not self.addModel():
            return retcode
        self.protocol.constrainVariablesAPI(self.context)
        if self.context.status() == Status.UNSAT:
            print('The model appears to be UNSAT: smt_stat = {}\n'.format(self.context.status()))
            print('For more information use the --consistency option.\n')
            return retcode
        # The meaning of the levels:
        #
        # 0.  Just the events
        # 1.  The events plus the distinctness of each timeline:  distinct(varlist) for timeline(bot, varlist) in facts.
        # 2.  The events plus the ascendingness of each timeline
        for level in range(0, 4):
            #print('context status: ', Status.name(self.context.status()))
            self.context.push()
            assertions = self.getProtocolIncrementally(level)
            alen = len(assertions)
            if alen:
                smt_stat = self.context.check_context_with_assumptions(None, assertions)
                sys.stderr.write('Level {0}: context.check_context_with_assumptions returned {1}\n'.format(level, Status.name(smt_stat)))
                if smt_stat == Status.SAT:
                    #get the model
                    model = Model.from_context(self.context, 1)
                    print('Level {0} has a solution: smt_stat = {1}\n'.format(level, smt_stat))
                    self.print_solution(model)
                    model.dispose()
                elif smt_stat == Status.UNSAT:
                    unsat_core = self.context.get_unsat_core()
                    if not unsat_core:
                        sys.stderr.write('unsat_core is empty\n')
                    else:
                        print('Level {0} unsat core is:\n'.format(level))
                        for term in unsat_core:
                            Terms.print_to_fd(1, term, 80, 100, 0)
                        print('')
                    return 0
                else:
                    sys.stderr.write('context.check_context_with_assumptions returned {0}\n'.format(Status.name(smt_stat)))
            self.context.pop()
        self._cleanUp()
        return 0


    def exhaust(self):
        result = 0
        self.context.push()
        if not self.addFacts():
            print('Bummer')
            return 2
        # BD says: this is complete but crude
        # another way would be to use 'yices_assert_blocking_clause'
        while  self.context.check_context() == Status.SAT:
            model = Model.from_context(self.context, 1)
            self.print_solution(model, 'Model #{0}:'.format(result))
            diagram = YicesSignature.model2term(model)
            self.context.assert_formula(Terms.ynot(diagram))
            model.dispose()
            result += 1
            if result == Configuration.aleph_nought:
                break
        self.context.pop()
        print("I found {1} distinct model{2} (using an upper limit of {0})".format(Configuration.aleph_nought, result, "" if result == 1 else "s"))
        return result



    def unsat_core(self):
        retcode = 2
        if not self.addModel():
            sys.stderr.write('addModel failed\n')
            return retcode
        self.protocol.constrainVariablesAPI(self.context)
        smt_stat = self.context.check_context()
        #sys.stderr.write('context.check_context returned {0}\n'.format(Status.name(smt_stat)))
        if smt_stat == Status.UNSAT:
            sys.stderr.write('The model is UNSAT: something is rotten in the State\n')
            retcode = 1
            return retcode
        assertions = self.protocol.toYicesTerms()
        alen = len(assertions)
        if alen:
            smt_stat = self.context.check_context_with_assumptions(None, assertions)
            sys.stderr.write('context.check_context_with_assumptions returned {0}\n'.format(Status.name(smt_stat)))
            if smt_stat == Status.SAT:
                sys.stderr.write('Calling unsat_core on a satisfiable theory is user error\n')
                retcode = 1
            elif smt_stat == Status.UNSAT:
                unsat_core = self.context.get_unsat_core()
                if not unsat_core:
                    sys.stderr.write('unsat_core is empty\n')
                else:
                    for term in unsat_core:
                        Terms.print_to_fd(1, term, 80, 100, 0)
            else:
                retcode = 1
            retcode = 0
        self._cleanUp()
        return retcode


    def missing(self):
        retcode = 2
        if not self.addModel():
            sys.stderr.write('addModel failed\n')
            return retcode
        self.protocol.constrainVariablesAPI(self.context)
        timelines = self.protocol.timelines
        tlen = len(timelines)
        interpretation = Configuration.timeline_interpretation
        tint_text = Configuration.INTERPRETATIONS[interpretation]
        print('There are {0} timelines ({1})\n'.format(tlen, tint_text))
        if not timelines:
            return retcode
        for timeline in timelines:
            formula = timeline.toYicesTerm(interpretation)
            yassert_formula(self, formula)
        smt_stat = self.context.check_context()
        if smt_stat == Status.UNSAT:
            sys.stderr.write('The model is UNSAT: something is rotten in the State\n')
            retcode = 1
            return retcode
        for timeline in timelines:
            satisfiable = True
            yevents = [ ]
            for eindex, timevar in enumerate(timeline.varlist):
                events = self.protocol.event_map[timevar]
                for e in events:
                    yevents.append(e.yices_term)
                smt_stat = self.context.check_context_with_assumptions(None, yevents)
                if smt_stat == Status.UNSAT:
                    satisfiable = False
                    print('UNSAT at level {0}, i.e. timestamp {1}'.format(eindex, timevar))
                    unsat_core = self.context.get_unsat_core()
                    print("\nUnsat core :\n")
                    for term in unsat_core:
                        Terms.print_to_fd(1, term, 80, 100, 0)
                    print("\n")
                    break
                elif self.verbose and smt_stat == Status.SAT:
                    print('SAT at level {0}, i.e. timestamp {1}'.format(eindex, timevar))
                    model = Model.from_context(self.context, 1)
                    self.print_solution(model, header=None, frees=timeline.fv)
                    model.dispose()
            if satisfiable:
                print('Timeline of {0} OK ({1}):\n'.format(timeline.term, tint_text))  #print a model
                model = Model.from_context(self.context, 1)
                self.print_solution(model, header=None, frees=timeline.fv)
                model.dispose()
        retcode = 0
        self._cleanUp()
        return retcode



    def print_solution(self, model, header=None, frees=None):

        def print_int(v):
            ytvar = v.yices_term
            ytval = model.get_value(ytvar)
            print('\t{0} is {1}'.format(v.name, ytval))


        if header is not None:
            print(header)

        if frees is None:
            nv = YicesSignature.get_vars(SymbolTable.NAT)
            for nvar in nv:
                print_int(nvar)
            tv = YicesSignature.get_vars(SymbolTable.TIME)
            for tvar in tv:
                if tvar.name == SymbolTable.MAXTIME:
                    continue
                print_int(tvar)
            pv = YicesSignature.get_vars(SymbolTable.PT2)
            for ptvar in pv:
                if ptvar.name == SymbolTable.NOLOC:
                    continue
                ytvar = ptvar.yices_term
                ytval = model.get_value(ytvar)
                val = YicesSignature.pt2_invmap[ytval]
                print('\t{0} is {1}'.format(ptvar.name, val))
        else:
            frees = list(frees)
            frees.sort()
            for var in frees:
                ytvar = var.yices_term
                ytval = model.get_value(ytvar)
                if var.vartype.name == 'Pt2':
                    ytval = YicesSignature.pt2_invmap[ytval]
                print('\t{0} is {1}'.format(var.name, ytval))


    def frontier(self):
        retcode = 2
        if not self.addModel():
            return retcode
        self.protocol.constrainVariablesAPI(self.context)
        searchSpace = Frontier(self.protocol)
        interpretation = Configuration.timeline_interpretation
        tint_text = Configuration.INTERPRETATIONS[interpretation]
        print('The timeline interpretation is: {0}\n'.format(tint_text))
        while not searchSpace.finished():
            point = searchSpace.nextElement()
            if point is None:
                break
            if self.verbose:
                print(point)
            assertions = self.protocol.toYicesTerms(point)
            alen = len(assertions)
            if alen:
                smt_stat = self.context.check_context_with_assumptions(None, assertions)
                if smt_stat == Status.SAT:
                    if self.verbose:
                        print('SAT')
                        #get the model
                        model = Model.from_context(self.context, 1)
                        self.print_solution(model, header=None, frees=self.protocol.FV(point))
                        model.dispose()
                elif smt_stat == Status.UNSAT:
                    searchSpace.addUnsat(point)
                    if self.verbose:
                        print('UNSAT')
                        unsat_core = self.context.get_unsat_core()
                        print("\nUnsat core:\n")
                        for term in unsat_core:
                            Terms.print_to_fd(1, term, 80, 100, 0)
                        print("\n")
            else:
                sys.stderr.write('context.check_context_with_assumptions returned {0}\n', smt_stat)
        print('Frontier: {0}'.format(searchSpace.frontier))
        self._cleanUp()
        return retcode


    def entire(self):
        retcode = 2
        if not self.addModel():
            return retcode
        self.protocol.constrainVariablesAPI(self.context)
        searchSpace = Frontier(self.protocol)
        tower = list(searchSpace.tower())
        tower.sort()
        for point in tower:
            print(point)
            assertions = self.protocol.toYicesTerms(point)
            alen = len(assertions)
            if alen:
                smt_stat = self.context.check_context_with_assumptions(None, assertions)
                if smt_stat == Status.SAT:
                    print('SAT')
                    #get the model
                    model = Model.from_context(self.context, 1)
                    self.print_solution(model, header=None, frees=self.protocol.FV(point))
                    model.dispose()
                elif smt_stat == Status.UNSAT:
                    print('UNSAT')
                    unsat_core = self.context.get_unsat_core()
                    print("\nUnsat core:\n")
                    for term in unsat_core:
                        Terms.print_to_fd(1, term, 80, 100, 0)
                    print("\n")
                else:
                    sys.stderr.write('context.check_context_with_assumptions returned {0}\n', smt_stat)
        self._cleanUp()
        return retcode




    def _cleanUp(self):
        self.context.dispose()
        Yices.exit()