Exemplo n.º 1
0
    def applyRestrictUp(self, u, literal):
        if u.isLeaf():
            return (u, resolver.tautologyId)
        rvar = literal.variable
        nvar = u.variable
        phase1 = literal.high == self.leaf1
        if rvar < nvar:
            return (u, resolver.tautologyId)
        elif rvar == nvar:
            result = u.high if phase1 else u.low
            just = u.inferTrueUp if phase1 else u.inferFalseUp
            return (result, just)
        
        key = ("resup", u.id, literal.id)
        if key in self.operationCache:
            return self.operationCache[key][:2]

        ruleIndex = { }
        uhigh = u.high
        ruleIndex["UHX"] = u.inferTrueUp
        ulow = u.low
        ruleIndex["ULX"] = u.inferFalseUp

        (vhigh, resHigh) = self.applyRestrictUp(uhigh, literal)
        ruleIndex["RESH"] = resHigh
        (vlow, resLow)   = self.applyRestrictUp(ulow, literal)
        ruleIndex["RESL"] = resLow
        
        if vhigh == vlow:
            v = vhigh
        else:
            v = self.findOrMake(nvar, vhigh, vlow)
            ruleIndex["VHX"] = v.inferTrueDown
            ruleIndex["VLX"] = v.inferFalseDown
        
        targetClause = resolver.cleanClause([-rvar.id if phase1 else rvar.id, u.id, -v.id])
        if targetClause == resolver.tautologyId:
            justification, clauseList = resolver.tautologyId, []
        else:
            try:
                comment = "Justification that %s%s & %s ==> %s" % ("" if phase1 else "!", rvar.name, v.label(), u.label())
                justification, clauseList = self.restrictResolver.run(targetClause, ruleIndex, comment)
            except resolver.ResolveException:
                targetClause = resolver.cleanClause([u.id, -v.id])
                comment = "Degenerate restriction.  Justification that %s ==> %s" % (v.label(), u.label())
                justification, clauseList = self.restrictResolver.run(targetClause, ruleIndex, comment)
                # Record this for use by the prover
                self.prover.restrictDegeneracies.add(justification)
        self.operationCache[key] = (v, justification,clauseList)
        self.cacheJustifyAdded += 1
        return (v, justification)
Exemplo n.º 2
0
 def createClause(self, result, antecedent, comment=None, isInput=False):
     self.comment(comment)
     result = resolver.cleanClause(result)
     if result == resolver.tautologyId:
         return result
     if result == -resolver.tautologyId:
         result = []
     self.clauseCount += 1
     antecedent = list(antecedent)
     if not self.doLrat:
         antecedent.sort()
     middle = [ord('a')] if self.doBinary else []
     rest = result + [0] + antecedent + [0]
     ilist = [self.clauseCount] + middle + rest
     if self.doBinary:
         if isInput and self.doLrat:
             pass
         else:
             bytes = stream.CompressArray(ilist).bytes
             self.file.write(bytes)
     else:
         slist = [str(i) for i in ilist]
         istring = " ".join(slist)
         if isInput and self.doLrat:
             self.comment(istring)
         else:
             self.file.write(istring + '\n')
     self.clauseDict[self.clauseCount] = result
     return self.clauseCount
Exemplo n.º 3
0
 def createClause(self, result, antecedent = [], comment = None, isInput = False, isUniversal = False, ulit = None):
     self.comment(comment)
     result = resolver.cleanClause(result, nosort = isUniversal)
     if result == resolver.tautologyId:
         return result
     self.clauseCount += 1
     antecedent = list(antecedent)
     middle = ['u'] if isUniversal else []
     rest = result + [0]
     if self.mode in [ProverMode.refProof, ProverMode.dualProof] and not self.doQrat:
         rest += antecedent + [0]
     ilist = [self.clauseCount] if not self.doQrat else []
     ilist += middle + rest
     slist = [str(i) for i in ilist]
     istring = " ".join(slist)
     if isInput:
         self.comment(istring)
     else:
         self.file.write(istring + '\n')
     if isUniversal and ulit is not None:
         result = [lit for lit in result if lit != ulit]
     self.clauseDict[self.clauseCount] = result
     if len(antecedent) > 0:
         self.antecedentDict[self.clauseCount] = antecedent
     return self.clauseCount
Exemplo n.º 4
0
    def applyAndJustify(self, nodeA, nodeB):
        self.applyCount += 1
        # Constant cases.
        # No justifications required, since all return one of the arguments
        if nodeA == self.leaf0 or nodeB == self.leaf0:
            return (self.leaf0, resolver.tautologyId)
        if nodeA == self.leaf1:
            return (nodeB, resolver.tautologyId)
        if nodeB == self.leaf1:
            return (nodeA, resolver.tautologyId)
        if nodeA == nodeB:
            return (nodeA, resolver.tautologyId)

        if nodeA.id > nodeB.id:
            nodeA, nodeB = nodeB, nodeA
        key = ("and", nodeA.id, nodeB.id)
        if key in self.operationCache:
            return self.operationCache[key][:2]

        # Mapping from rule names to clause numbers
        ruleIndex = {}
        # Mapping from variable names to variable numbers
        splitVar = min(nodeA.variable, nodeB.variable)
        highA = nodeA.branchHigh(splitVar)
        lowA = nodeA.branchLow(splitVar)
        highB = nodeB.branchHigh(splitVar)
        lowB = nodeB.branchLow(splitVar)

        if highA != lowA:
            ruleIndex["UHD"] = nodeA.inferTrueDown
            ruleIndex["ULD"] = nodeA.inferFalseDown
        if highB != lowB:
            ruleIndex["VHD"] = nodeB.inferTrueDown
            ruleIndex["VLD"] = nodeB.inferFalseDown

        (newHigh, andHigh) = self.applyAndJustify(highA, highB)
        ruleIndex["ANDH"] = andHigh

        (newLow, andLow) = self.applyAndJustify(lowA, lowB)
        ruleIndex["ANDL"] = andLow

        if newHigh == newLow:
            newNode = newHigh
        else:
            newNode = self.findOrMake(splitVar, newHigh, newLow)
            ruleIndex["WHU"] = newNode.inferTrueUp
            ruleIndex["WLU"] = newNode.inferFalseUp

        targetClause = resolver.cleanClause([-nodeA.id, -nodeB.id, newNode.id])
        if targetClause == resolver.tautologyId:
            justification, clauseList = resolver.tautologyId, []
        else:
            comment = "Justification that %s & %s ==> %s" % (
                nodeA.label(), nodeB.label(), newNode.label())
            justification, clauseList = self.andResolver.run(
                targetClause, ruleIndex, comment)
        self.operationCache[key] = (newNode, justification, clauseList)
        self.cacheJustifyAdded += 1
        return (newNode, justification)
Exemplo n.º 5
0
    def justifyImply(self, nodeA, nodeB):
        self.applyCount += 1

        # Special cases
        if nodeA == nodeB:
            return (True, resolver.tautologyId)
        if nodeA == self.leaf0:
            return (True, resolver.tautologyId)
        if nodeB == self.leaf1:
            return (True, resolver.tautologyId)
        # It would be an error if implication fails
        if nodeA == self.leaf1:
            return (False, resolver.tautologyId)
        if nodeB == self.leaf0:
            return (False, resolver.tautologyId)

        key = ("imply", nodeA.id, nodeB.id)
        if key in self.operationCache:
            return self.operationCache[key][:2]

        ruleIndex = {}
        splitVar = min(nodeA.variable, nodeB.variable)
        highA = nodeA.branchHigh(splitVar)
        lowA = nodeA.branchLow(splitVar)
        highB = nodeB.branchHigh(splitVar)
        lowB = nodeB.branchLow(splitVar)

        if highA != lowA:
            ruleIndex["UHD"] = nodeA.inferTrueDown
            ruleIndex["ULD"] = nodeA.inferFalseDown
        if highB != lowB:
            ruleIndex["VHU"] = nodeB.inferTrueUp
            ruleIndex["VLU"] = nodeB.inferFalseUp

        (checkHigh, implyHigh) = self.justifyImply(highA, highB)
        if implyHigh != resolver.tautologyId:
            ruleIndex["IMH"] = implyHigh
        (checkLow, implyLow) = self.justifyImply(lowA, lowB)
        if implyLow != resolver.tautologyId:
            ruleIndex["IML"] = implyLow

        check = checkHigh and checkLow
        if check:
            targetClause = resolver.cleanClause([-nodeA.id, nodeB.id])
            comment = "Justification that %s ==> %s" % (nodeA.label(),
                                                        nodeB.label())
            justification, clauseList = self.implyResolver.run(
                targetClause, ruleIndex, comment)
        else:
            justification, clauseList = resolver.tautologyId, []

        self.operationCache[key] = (check, justification, clauseList)
        if justification != resolver.tautologyId:
            self.cacheJustifyAdded += 1
        else:
            self.cacheNoJustifyAdded += 1
        return (check, justification)
Exemplo n.º 6
0
 def proveAdd(self, result, comment = None):
     result = resolver.cleanClause(result)
     if result == resolver.tautologyId:
         self.comment(comment)
         return result
     rfields = [str(r) for r in result]
     fields = ['a'] + rfields + ['0']
     stepNumber = self.generateStepQP(fields, True, comment)
     self.clauseDict[stepNumber] = result
     if self.doQrat:
         return self.createClause(result, comment)
     return stepNumber
Exemplo n.º 7
0
 def proveAddBlocked(self, clause, blockers, comment = None):
     result = resolver.cleanClause(clause)
     if result == resolver.tautologyId:
         self.comment(comment)
         return result
     rfields = [str(r) for r in result]
     cmd =  'ab' if self.mode in [ProverMode.refProof, ProverMode.dualProof] else 'a'
     fields = [cmd] + rfields + ['0']
     if self.mode in [ProverMode.refProof, ProverMode.dualProof]:
         bfields = [str(-abs(b)) for b in blockers]
         fields += bfields + ['0']
     stepNumber = self.generateStepQP(fields, True, comment)
     self.clauseDict[stepNumber] = result
     var = abs(clause[0])
     # Record defining clause
     qlevel = self.evarQlevels[var]
     self.qlevelEvars[qlevel][var].append(stepNumber)
     if self.doQrat:
         return self.createClause(result, blockers, comment)
     return stepNumber
Exemplo n.º 8
0
 def proveAddResolution(self, result, antecedent, comment = None):
     result = resolver.cleanClause(result)
     if result == resolver.tautologyId:
         self.comment(comment)
         return result
     rfields = [str(r) for r in result]
     afields = [str(a) for a in antecedent]
     cmd =  'ar' if self.mode in [ProverMode.refProof, ProverMode.dualProof] else 'a'
     fields = [cmd] + rfields + ['0']
     if self.mode in [ProverMode.refProof, ProverMode.dualProof]:
         afields = [str(a) for a in antecedent]
         fields += afields + ['0']
     stepNumber = self.generateStepQP(fields, True, comment)
     if len(result) > 0 and self.mode in [ProverMode.satProof, ProverMode.refProof, ProverMode.dualProof]:
         qlevel = max([self.idToQlevel[abs(lit)] for lit in result])
         if qlevel in self.qlevelClauses:
             self.qlevelClauses[qlevel].append(stepNumber)
         else:
             self.qlevelClauses[qlevel] = [stepNumber]
     self.clauseDict[stepNumber] = result
     self.antecedentDict[stepNumber] = antecedent
     if self.doQrat:
         self.file.write(' '.join(rfields) + ' 0\n')
     return stepNumber
Exemplo n.º 9
0
 def createClause(self, result, antecedent, comment=None):
     result = resolver.cleanClause(result)
     if result == resolver.tautologyId:
         return result
     self.clauseCount += 1
     return self.clauseCount