private bool Solve_Brtrue(CflowStack stack)
{
var val1 = stack.Pop();
if (val1 is BitVecExpr)
{
FinalExpr = ctx.MkEq(val1 as BitVecExpr, ctx.MkBV(0, 32));
if ((val1 as BitVecExpr).Simplify().IsNumeral)
{
Microsoft.Z3.Solver s = ctx.MkSolver();
s.Assert(FinalExpr);
if (s.Check() == Status.UNSATISFIABLE)
{
this.PopPushedArgs(1);
block.ReplaceBccWithBranch(true);
return(true);
}
else
{
this.PopPushedArgs(1);
block.ReplaceBccWithBranch(false);
return(true);
}
}
}
return(false);
}
/// <summary>
/// Try to find a configuration with low weight.
/// </summary>
/// <param name="sortedRanking">A list of binary options and their weight ordered by their weight.</param>
/// <param name="cache">A sat solver cache instance that already contains the constraints of
/// size and disallowed features.</param>
/// <param name="vm">The variability model of the given system.</param>
/// <returns>A configuration that has a small weight.</returns>
public static List <BinaryOption> getSmallWeightConfig(List <KeyValuePair <List <BinaryOption>, int> > sortedRanking,
Z3Cache cache, VariabilityModel vm)
{
KeyValuePair <List <BinaryOption>, int>[] ranking = sortedRanking.ToArray();
Microsoft.Z3.Solver solver = cache.GetSolver();
Context z3Context = cache.GetContext();
for (int i = 0; i < ranking.Length; i++)
{
List <BinaryOption> candidates = ranking[i].Key;
solver.Push();
solver.Assert(forceFeatures(candidates, z3Context, cache.GetOptionToTermMapping()));
if (solver.Check() == Status.SATISFIABLE)
{
Model model = solver.Model;
solver.Pop();
return(Z3VariantGenerator.RetrieveConfiguration(cache.GetVariables(), model,
cache.GetTermToOptionMapping()));
}
solver.Pop();
}
return(null);
}
private bool CheckBranch(Microsoft.Z3.Solver s1, Microsoft.Z3.Solver s2)
{
if (s1.Check() == Status.UNSATISFIABLE)
{
// opaque predicate not taken
this.PopPushedArgs(2);
block.ReplaceBccWithBranch(false);
return(true);
}
else if (s2.Check() == Status.UNSATISFIABLE)
{
// opaque predicate taken
this.PopPushedArgs(2);
block.ReplaceBccWithBranch(true);
return(true);
}
else
{
return(false);
}
}
protected override void AddControllerOverflow(Microsoft.Z3.Context ctx, Microsoft.Z3.Solver solver, string varName)
{
FixedPointNumber var = discreteVariablesByName[varName];
FixedPointNumber expr = assigns[varName];
solver.Assert(expr.overflow);
}
/// <summary>
/// This constructor creates a new <see cref="ConstraintSystemCache"/> with the given parameters.
/// </summary>
/// <param name="context">The <see cref="Context"/> to store.</param>
/// <param name="solver">The <see cref="Microsoft.Z3.Solver"/>-object to use.</param>
/// <param name="variables">The variables used in the <see cref="Context"/>.</param>
/// <param name="optionToTerm">The mapping from <see cref="BinaryOption"/> to <see cref="BoolExpr"/>.</param>
/// <param name="termToOption">The mapping from <see cref="BoolExpr"/> to <see cref="BinaryOption"/>.</param>
public Z3Cache(Context context, Microsoft.Z3.Solver solver, List <BoolExpr> variables, Dictionary <BinaryOption, BoolExpr> optionToTerm, Dictionary <BoolExpr, BinaryOption> termToOption)
{
this._context = context;
this._solver = solver;
this._variables = variables;
this._optionToTerm = optionToTerm;
this._termToOption = termToOption;
}
/// <summary>
/// Add controller code for output/memory variable 'var'
/// </summary>
/// <param name="ctx"></param>
/// <param name="solver"></param>
/// <param name="variable"></param>
protected override void AddController(Microsoft.Z3.Context ctx, Microsoft.Z3.Solver solver, string varName)
{
FixedPointNumber var = discreteVariablesByName[varName];
FixedPointNumber expr = assigns[varName];
BoolExprWithOverflow assert = ctx.MkFPEq(var, expr);
solver.Assert(assert.bv);
}
public bool SolveBranchAssisted(Context ctx, BoolExpr expr)
{
Instruction instr = block.LastInstr.Instruction;
if (instr.OpCode.Code == Code.Brfalse || instr.OpCode.Code == Code.Brfalse_S)
{
Microsoft.Z3.Solver s = ctx.MkSolver();
s.Assert(expr);
if (s.Check() == Status.SATISFIABLE)
{
this.PopPushedArgs(1);
block.ReplaceBccWithBranch(true);
return(true);
}
else
{
this.PopPushedArgs(1);
block.ReplaceBccWithBranch(false);
return(true);
}
}
else if (instr.OpCode.Code == Code.Brtrue || instr.OpCode.Code == Code.Brtrue_S)
{
Microsoft.Z3.Solver s = ctx.MkSolver();
s.Assert(expr);
if (s.Check() == Status.UNSATISFIABLE)
{
this.PopPushedArgs(1);
block.ReplaceBccWithBranch(true);
return(true);
}
else
{
this.PopPushedArgs(1);
block.ReplaceBccWithBranch(false);
return(true);
}
}
else
{
Microsoft.Z3.Solver s1 = ctx.MkSolver();
Microsoft.Z3.Solver s2 = ctx.MkSolver();
s1.Add(expr);
s2.Add(ctx.MkNot(expr));
return(this.CheckBranch(s1, s2));
}
}
// Constructor
public SolverContext(Modelling.BLOs.Model model)
{
// Create an empty z3 context
Dictionary <string, string> configSettings = new Dictionary <string, string>();
configSettings["MODEL"] = "true";
configSettings["MACRO_FINDER"] = "true";
_context = new Context(configSettings);
_context.PrintMode = Z3_ast_print_mode.Z3_PRINT_SMTLIB2_COMPLIANT;
// Setup the z3 context and solver
_solver = _context.MkSolver();
// Setup custom conversion method BoolToInt (boolean -> integer)
FuncDecl boolToInt = _context.MkFuncDecl("BoolToInt", _context.MkBoolSort(), _context.MkIntSort());
Expr i = _context.MkConst("i", _context.MkBoolSort());
Expr fDef = _context.MkITE(_context.MkEq(i, _context.MkTrue()), _context.MkInt(1), _context.MkInt(0)); // x == true => 1, x == false => 0
Expr fStatement = _context.MkForall(new Expr[] { i }, _context.MkEq(_context.MkApp(boolToInt, i), fDef));
_solver.Assert(fStatement as BoolExpr);
_functions.Add("BoolToInt", new Function(boolToInt));
// Create the static part (constants and constraints)
model.Features.ForEach(feature =>
{
string featureSID = GenerateFeatureSID(feature.Identifier);
AddFeature_Constant(feature.Identifier);
feature.Attributes.ForEach(attribute => AddAttribute_Constant(attribute.Identifier, feature.Identifier, attribute.AttributeDataType));
});
model.Relations.ForEach(relation =>
{
AddRelation_Constraint(relation.RelationType, relation.ParentFeature.Identifier, relation.ChildFeature.Identifier);
});
model.GroupRelations.ForEach(groupRelation =>
{
string[] childFeatureIDs = groupRelation.ChildFeatures.Select(feature => feature.Identifier).ToArray();
AddGroupRelation_Constraint(groupRelation.GroupRelationType, groupRelation.ParentFeature.Identifier, childFeatureIDs,
groupRelation.UpperBound ?? default(int), groupRelation.LowerBound ?? default(int));
});
model.CompositionRules.ForEach(compRule =>
{
AddCompositionRule_Constraint(compRule.CompositionRuleType, compRule.FirstFeature.Identifier, compRule.SecondFeature.Identifier);
});
// Create initial point
_solver.Push();
}
/// <summary>
/// Generates all valid combinations of all configuration options in the given model.
/// </summary>
/// <param name="vm">the variability model containing the binary options and their constraints</param>
/// <param name="optionsToConsider">the options that should be considered. All other options are ignored</param>
/// <returns>Returns a list of <see cref="Configuration"/></returns>
public List <Configuration> GenerateAllVariants(VariabilityModel vm, List <ConfigurationOption> optionsToConsider)
{
List <Configuration> allConfigurations = new List <Configuration>();
List <BoolExpr> variables;
Dictionary <BoolExpr, BinaryOption> termToOption;
Dictionary <BinaryOption, BoolExpr> optionToTerm;
Tuple <Context, BoolExpr> z3Tuple = Z3Solver.GetInitializedBooleanSolverSystem(out variables, out optionToTerm, out termToOption, vm, this.henard);
Context z3Context = z3Tuple.Item1;
BoolExpr z3Constraints = z3Tuple.Item2;
Microsoft.Z3.Solver solver = z3Context.MkSolver();
// TODO: The following line works for z3Solver version >= 4.6.0
//solver.Set (RANDOM_SEED, z3RandomSeed);
Params solverParameter = z3Context.MkParams();
solverParameter.Add(RANDOM_SEED, z3RandomSeed);
solver.Parameters = solverParameter;
solver.Assert(z3Constraints);
while (solver.Check() == Status.SATISFIABLE)
{
Model model = solver.Model;
List <BinaryOption> binOpts = RetrieveConfiguration(variables, model, termToOption, optionsToConsider);
Configuration c = new Configuration(binOpts);
// Check if the non-boolean constraints are satisfied
if (vm.configurationIsValid(c) && !VariantGenerator.IsInConfigurationFile(c, allConfigurations) && VariantGenerator.FulfillsMixedConstraints(c, vm))
{
allConfigurations.Add(c);
}
solver.Push();
solver.Assert(Z3Solver.NegateExpr(z3Context, Z3Solver.ConvertConfiguration(z3Context, binOpts, optionToTerm, vm)));
}
solver.Push();
solver.Pop(Convert.ToUInt32(allConfigurations.Count() + 1));
return(allConfigurations);
}
public bool checkConfigurationSAT(List <BinaryOption> config, VariabilityModel vm, bool partialConfiguration)
{
List <BoolExpr> variables;
Dictionary <BoolExpr, BinaryOption> termToOption;
Dictionary <BinaryOption, BoolExpr> optionToTerm;
Tuple <Context, BoolExpr> z3Tuple = Z3Solver.GetInitializedBooleanSolverSystem(out variables, out optionToTerm, out termToOption, vm, false);
Context z3Context = z3Tuple.Item1;
BoolExpr z3Constraints = z3Tuple.Item2;
List <BoolExpr> constraints = new List <BoolExpr>();
Microsoft.Z3.Solver solver = z3Context.MkSolver();
solver.Assert(z3Constraints);
solver.Assert(Z3Solver.ConvertConfiguration(z3Context, config, optionToTerm, vm, partialConfiguration));
if (solver.Check() == Status.SATISFIABLE)
{
return(true);
}
return(false);
}
public bool checkConfigurationSAT(Configuration c, VariabilityModel vm, bool partialConfiguration = false)
{
List <Expr> variables;
Dictionary <Expr, ConfigurationOption> termToOption;
Dictionary <ConfigurationOption, Expr> optionToTerm;
Tuple <Context, BoolExpr> z3Tuple = Z3Solver.GetInitializedSolverSystem(out variables, out optionToTerm, out termToOption, vm);
Context z3Context = z3Tuple.Item1;
BoolExpr z3Constraints = z3Tuple.Item2;
List <Expr> constraints = new List <Expr>();
Microsoft.Z3.Solver solver = z3Context.MkSolver();
solver.Assert(z3Constraints);
solver.Assert(Z3Solver.ConvertConfiguration(z3Context, c.getBinaryOptions(BinaryOption.BinaryValue.Selected), optionToTerm, vm, partialConfiguration, c.NumericOptions));
if (solver.Check() == Status.SATISFIABLE)
{
return(true);
}
return(false);
}
/// <summary>
/// Generates all valid combinations of all configuration options in the given model.
/// </summary>
/// <param name="vm">the variability model containing the binary options and their constraints</param>
/// <param name="optionsToConsider">the options that should be considered. All other options are ignored</param>
/// <returns>Returns a list of <see cref="Configuration"/></returns>
public List <Configuration> GenerateAllVariants(VariabilityModel vm, List <ConfigurationOption> optionsToConsider)
{
List <Configuration> allConfigurations = new List <Configuration>();
List <Expr> variables;
Dictionary <Expr, ConfigurationOption> termToOption;
Dictionary <ConfigurationOption, Expr> optionToTerm;
Tuple <Context, BoolExpr> z3Tuple = Z3Solver.GetInitializedSolverSystem(out variables, out optionToTerm, out termToOption, vm);
Context z3Context = z3Tuple.Item1;
BoolExpr z3Constraints = z3Tuple.Item2;
Microsoft.Z3.Solver solver = z3Context.MkSolver();
solver.Set(RANDOM_SEED, z3RandomSeed);
solver.Assert(z3Constraints);
while (solver.Check() == Status.SATISFIABLE)
{
Model model = solver.Model;
Tuple <List <BinaryOption>, Dictionary <NumericOption, double> > confOpts = RetrieveConfiguration(variables, model, termToOption, optionsToConsider);
Configuration c = new Configuration(confOpts.Item1, confOpts.Item2);
// Check if the non-boolean constraints are satisfied
bool configIsValid = vm.configurationIsValid(c);
bool isInConfigurationFile = !VariantGenerator.IsInConfigurationFile(c, allConfigurations);
bool fulfillsMixedConstraintrs = VariantGenerator.FulfillsMixedConstraints(c, vm);
if (configIsValid && isInConfigurationFile && fulfillsMixedConstraintrs)
{
allConfigurations.Add(c);
}
solver.Push();
solver.Assert(Z3Solver.NegateExpr(z3Context, Z3Solver.ConvertConfiguration(z3Context, confOpts.Item1, optionToTerm, vm, numericValues: confOpts.Item2)));
}
solver.Push();
solver.Pop(Convert.ToUInt32(allConfigurations.Count() + 1));
return(allConfigurations);
}
private bool Solve_Bne_Un(CflowStack stack)
{
var val2 = stack.Pop();
var val1 = stack.Pop();
if (val1 is BitVecExpr && val2 is BitVecExpr)
{
FinalExpr = ctx.MkNot(ctx.MkEq(val1 as BitVecExpr, val2 as BitVecExpr));
if ((val1 as BitVecExpr).Simplify().IsNumeral&& (val2 as BitVecExpr).Simplify().IsNumeral)
{
Microsoft.Z3.Solver s1 = ctx.MkSolver();
Microsoft.Z3.Solver s2 = ctx.MkSolver();
s1.Add(FinalExpr);
s2.Add(ctx.MkNot(FinalExpr));
return(this.CheckBranch(s1, s2));
}
}
return(false);
}
/// <summary>
/// Generates up to n solutions of the given variability model.
/// Note that this method could also generate less than n solutions if the variability model does not contain sufficient solutions.
/// Moreover, in the case that <code>n < 0</code>, all solutions are generated.
/// </summary>
/// <param name="vm">The <see cref="VariabilityModel"/> to obtain solutions for.</param>
/// <param name="n">The number of solutions to obtain.</param>
/// <returns>A list of configurations, in which a configuration is a list of SELECTED binary options.</returns>
public List <List <BinaryOption> > GenerateUpToNFast(VariabilityModel vm, int n)
{
// Use the random seed to produce new random seeds
Random random = new Random(Convert.ToInt32(z3RandomSeed));
List <BoolExpr> variables;
Dictionary <BoolExpr, BinaryOption> termToOption;
Dictionary <BinaryOption, BoolExpr> optionToTerm;
Tuple <Context, BoolExpr> z3Tuple = Z3Solver.GetInitializedBooleanSolverSystem(out variables, out optionToTerm, out termToOption, vm, this.henard, random.Next());
Context z3Context = z3Tuple.Item1;
BoolExpr z3Constraints = z3Tuple.Item2;
List <BoolExpr> excludedConfigurations = new List <BoolExpr>();
List <BoolExpr> constraints = Z3Solver.lastConstraints;
List <List <BinaryOption> > configurations = new List <List <BinaryOption> >();
Microsoft.Z3.Solver s = z3Context.MkSolver();
// TODO: The following line works for z3Solver version >= 4.6.0
//solver.Set (RANDOM_SEED, z3RandomSeed);
Params solverParameter = z3Context.MkParams();
if (henard)
{
solverParameter.Add(RANDOM_SEED, NextUInt(random));
}
else
{
solverParameter.Add(RANDOM_SEED, z3RandomSeed);
}
s.Parameters = solverParameter;
s.Assert(z3Constraints);
s.Push();
Model model = null;
while (s.Check() == Status.SATISFIABLE && (configurations.Count < n || n < 0))
{
model = s.Model;
List <BinaryOption> config = RetrieveConfiguration(variables, model, termToOption);
configurations.Add(config);
if (henard)
{
BoolExpr newConstraint = Z3Solver.NegateExpr(z3Context, Z3Solver.ConvertConfiguration(z3Context, config, optionToTerm, vm));
excludedConfigurations.Add(newConstraint);
Dictionary <BoolExpr, BinaryOption> oldTermToOption = termToOption;
// Now, initialize a new one for the next configuration
z3Tuple = Z3Solver.GetInitializedBooleanSolverSystem(out variables, out optionToTerm, out termToOption, vm, this.henard, random.Next());
z3Context = z3Tuple.Item1;
z3Constraints = z3Tuple.Item2;
s = z3Context.MkSolver();
//s.Set (RANDOM_SEED, NextUInt (random));
solverParameter = z3Context.MkParams();
solverParameter.Add(RANDOM_SEED, NextUInt(random));
s.Parameters = solverParameter;
constraints = Z3Solver.lastConstraints;
excludedConfigurations = Z3Solver.ConvertConstraintsToNewContext(oldTermToOption, optionToTerm, excludedConfigurations, z3Context);
constraints.AddRange(excludedConfigurations);
s.Assert(z3Context.MkAnd(Z3Solver.Shuffle(constraints, new Random(random.Next()))));
s.Push();
}
else
{
s.Add(Z3Solver.NegateExpr(z3Context, Z3Solver.ConvertConfiguration(z3Context, config, optionToTerm, vm)));
}
}
return(configurations);
}
/// <summary>
/// This method searches for a corresponding methods in the dynamically loaded assemblies and calls it if found. It prefers due to performance reasons the Microsoft Solver Foundation implementation.
/// </summary>
/// <param name="config">The (partial) configuration which needs to be expaned to be valid.</param>
/// <param name="vm">Variability model containing all options and their constraints.</param>
/// <param name="minimize">If true, we search for the smallest (in terms of selected options) valid configuration. If false, we search for the largest one.</param>
/// <param name="unWantedOptions">Binary options that we do not want to become part of the configuration. Might be part if there is no other valid configuration without them.</param>
/// <returns>The valid configuration (or null if there is none) that satisfies the VM and the goal.</returns>
public List <BinaryOption> MinimizeConfig(List <BinaryOption> config, VariabilityModel vm, bool minimize, List <BinaryOption> unWantedOptions)
{
List <BoolExpr> variables;
Dictionary <BoolExpr, BinaryOption> termToOption;
Dictionary <BinaryOption, BoolExpr> optionToTerm;
Tuple <Context, BoolExpr> z3Tuple = Z3Solver.GetInitializedBooleanSolverSystem(out variables, out optionToTerm, out termToOption, vm, this.henard);
Context z3Context = z3Tuple.Item1;
BoolExpr z3Constraints = z3Tuple.Item2;
List <BoolExpr> constraints = new List <BoolExpr>();
constraints.Add(z3Constraints);
//Feature Selection
foreach (BinaryOption binOpt in config)
{
BoolExpr term = optionToTerm[binOpt];
constraints.Add(term);
}
Model model = null;
if (minimize == true)
{
//Defining Goals
ArithExpr[] optimizationGoals = new ArithExpr[variables.Count];
for (int r = 0; r < variables.Count; r++)
{
BinaryOption currOption = termToOption[variables[r]];
ArithExpr numericVariable = z3Context.MkIntConst(currOption.Name);
int weight = 1;
if (unWantedOptions != null && (unWantedOptions.Contains(termToOption[variables[r]]) && !config.Contains(termToOption[variables[r]])))
{
weight = 1000;
}
constraints.Add(z3Context.MkEq(numericVariable, z3Context.MkITE(variables[r], z3Context.MkInt(weight), z3Context.MkInt(0))));
optimizationGoals[r] = numericVariable;
}
// For minimization, we need the class 'Optimize'
Optimize optimizer = z3Context.MkOptimize();
optimizer.Assert(constraints.ToArray());
optimizer.MkMinimize(z3Context.MkAdd(optimizationGoals));
if (optimizer.Check() != Status.SATISFIABLE)
{
return(new List <BinaryOption>());
}
else
{
model = optimizer.Model;
}
}
else
{
// Return the first configuration returned by the solver
Microsoft.Z3.Solver solver = z3Context.MkSolver();
// TODO: The following line works for z3Solver version >= 4.6.0
//solver.Set (RANDOM_SEED, z3RandomSeed);
Params solverParameter = z3Context.MkParams();
solverParameter.Add(RANDOM_SEED, z3RandomSeed);
solver.Parameters = solverParameter;
solver.Assert(constraints.ToArray());
if (solver.Check() != Status.SATISFIABLE)
{
return(new List <BinaryOption>());
}
else
{
model = solver.Model;
}
}
List <BinaryOption> result = RetrieveConfiguration(variables, model, termToOption);
return(result);
}
public void ToSMTConstraints(Context z3Context, Solver z3Solver, int alphabetSize, VariableCache variableGenerator)
{
this.constraintVariable = variableGenerator.GetCharChoiceVariable(this.originalValue);
ArithExpr myVariable = z3Context.MkIntConst(this.constraintVariable);
z3Solver.Assert(z3Context.MkLe(z3Context.MkInt(0), myVariable));
z3Solver.Assert(z3Context.MkLe(myVariable, z3Context.MkInt(alphabetSize - 1)));
}
public void ToSMTConstraints(Context z3Context, Solver z3Solver, int alphabetSize, VariableCache variableGenerator)
{
this.constraintVariable = variableGenerator.GetIntegerChoiceVariable(this.originalValue);
ArithExpr myVariable = z3Context.MkIntConst(this.constraintVariable);
// For now, just concretize in the range [floor(origVal / 2), ceil(origVal * 1.5)]
z3Solver.Assert(z3Context.MkLe(z3Context.MkInt((int)(this.originalValue * 0.5)), myVariable));
z3Solver.Assert(z3Context.MkLe(myVariable, z3Context.MkInt((int)(this.originalValue * 1.5))));
if (this.includeZero == false)
{
z3Solver.Assert(z3Context.MkNot(z3Context.MkEq(z3Context.MkInt(0), myVariable)));
}
}
private static void GenerateConstraints(CPDLPred choicePred, HashSet<char> alphabet, VariableCache.ConstraintMode constraintMode, Context z3Context, Solver z3Solver)
{
VariableCache variableGenerator = VariableCache.Create(constraintMode);
choicePred.ToSMTConstraints(z3Context, z3Solver, alphabet.Count, variableGenerator);
variableGenerator.GenerateAdditionalConstraints(z3Context, z3Solver);
}
/// <summary>
/// Import model converter from other solver.
/// </summary>
public void ImportModelConverter(Solver src)
{
Native.Z3_solver_import_model_converter(Context.nCtx, src.NativeObject, NativeObject);
}
public override void ToSMTConstraints(Context z3Context, Solver z3Solver, int alphabetSize, VariableCache variableGenerator)
{
// Take a constraint variable just for good measure
this.constraintVariable = variableGenerator.GetFreshVariableName();
ArithExpr myVariable = z3Context.MkIntConst(this.constraintVariable);
z3Solver.Assert(z3Context.MkEq(myVariable, z3Context.MkInt(0)));
}
public abstract void GenerateVariableConstraints(Context z3Context, Solver z3Solver);
public void ToSMTConstraints(Context z3Context, Solver z3Solver, int alphabetSize, VariableCache variableGenerator)
{
this.constraintVariable = variableGenerator.GetStringChoiceVariable(this.originalValue);
ArithExpr myVariable = z3Context.MkIntConst(this.constraintVariable);
z3Solver.Assert(z3Context.MkLe(z3Context.MkInt(0), myVariable));
/* We have |s| * |\Sigma| options for concretizing this string
* Thus, since we are 0-based: originalValue.Length * alphabet - 1 */
z3Solver.Assert(z3Context.MkLe(myVariable, z3Context.MkInt(this.originalValue.Length * alphabetSize - 1)));
}
public abstract void ToSMTConstraints(Context z3Context, Solver z3Solver, int alphabetSize, VariableCache variableGenerator);
private static void ExcludeLastModel(IEnumerable<string> choiceVariables, Context z3Context, Solver z3Solver)
{
Model lastModel = z3Solver.Model;
BoolExpr characteristicFormula = CreateCharacteristicFormula(choiceVariables, z3Context, lastModel);
z3Solver.Assert(z3Context.MkNot(characteristicFormula));
}
internal Solver(Context context, Microsoft.Z3.Solver z3solver)
{
this.context = context;
this.solver = z3solver;
}
public override void GenerateVariableConstraints(Context z3Context, Solver z3Solver)
{
// Since we do not need any constraints, just do nothing. Basically a null-object
return;
}
/// <summary>
/// Demonstrate how to use <code>Push</code>and <code>Pop</code>to
/// control the size of models.
/// </summary>
/// <remarks>Note: this test is specialized to 32-bit bitvectors.</remarks>
public static void CheckSmall(Context ctx, Solver solver, BitVecExpr[] to_minimize)
{
Sort bv32 = ctx.MkBitVecSort(32);
int num_Exprs = to_minimize.Length;
UInt32[] upper = new UInt32[num_Exprs];
UInt32[] lower = new UInt32[num_Exprs];
BitVecExpr[] values = new BitVecExpr[num_Exprs];
for (int i = 0; i < upper.Length; ++i)
{
upper[i] = UInt32.MaxValue;
lower[i] = 0;
}
bool some_work = true;
int last_index = -1;
UInt32 last_upper = 0;
while (some_work)
{
solver.Push();
bool check_is_sat = true;
while (check_is_sat && some_work)
{
// Assert all feasible bounds.
for (int i = 0; i < num_Exprs; ++i)
{
solver.Assert(ctx.MkBVULE(to_minimize[i], ctx.MkBV(upper[i], 32)));
}
check_is_sat = Status.SATISFIABLE == solver.Check();
if (!check_is_sat)
{
if (last_index != -1)
{
lower[last_index] = last_upper + 1;
}
break;
}
Console.WriteLine("{0}", solver.Model);
// narrow the bounds based on the current model.
for (int i = 0; i < num_Exprs; ++i)
{
Expr v = solver.Model.Evaluate(to_minimize[i]);
UInt64 ui = ((BitVecNum)v).UInt64;
if (ui < upper[i])
{
upper[i] = (UInt32)ui;
}
Console.WriteLine("{0} {1} {2}", i, lower[i], upper[i]);
}
// find a new bound to add
some_work = false;
last_index = 0;
for (int i = 0; i < num_Exprs; ++i)
{
if (lower[i] < upper[i])
{
last_upper = (upper[i] + lower[i]) / 2;
last_index = i;
solver.Assert(ctx.MkBVULE(to_minimize[i], ctx.MkBV(last_upper, 32)));
some_work = true;
break;
}
}
}
solver.Pop();
}
}
public override void ToSMTConstraints(Context z3Context, Solver z3Solver, int alphabetSize, VariableCache variableGenerator)
{
this.constraintVariable = variableGenerator.GetFreshVariableName();
ArithExpr myVariable = z3Context.MkIntConst(this.constraintVariable);
z3Solver.Assert(z3Context.MkLe(z3Context.MkInt(0), myVariable));
z3Solver.Assert(z3Context.MkLe(myVariable, z3Context.MkInt(1)));
}
public override void ToSMTConstraints(Context z3Context, Solver z3Solver, int alphabetSize, VariableCache variableGenerator)
{
this.constraintVariable = variableGenerator.GetFreshVariableName();
ArithExpr myVariable = z3Context.MkIntConst(this.constraintVariable);
z3Solver.Assert(z3Context.MkEq(myVariable, z3Context.MkInt(0)));
this.originalPosition.ToSMTConstraints(z3Context, z3Solver, alphabetSize, variableGenerator);
this.originalSet.ToSMTConstraints(z3Context, z3Solver, alphabetSize, variableGenerator);
}
public void GenerateAdditionalConstraints(Context z3Context, Solver z3Solver)
{
this.constraintGenerator.GenerateVariableConstraints(z3Context, z3Solver);
}
public override void GenerateVariableConstraints(Context z3Context, Solver z3Solver)
{
this.GenerateInequalityConstraints(this.variableCache.GetIntegerVariables(), z3Context, z3Solver);
this.GenerateInequalityConstraints(this.variableCache.GetStringVariables(), z3Context, z3Solver);
this.GenerateInequalityConstraints(this.variableCache.GetCharVariables(), z3Context, z3Solver);
}
private void GenerateInequalityConstraints(ICollection<string> vars, Context z3Context, Solver z3Solver)
{
List<string> varList = new List<string>(vars);
for (int i = 0; i < varList.Count; ++i)
{
for (int j = i + 1; j < varList.Count; ++j)
{
// Assert vars[i] != vars[j]
z3Solver.Assert(
z3Context.MkNot(
z3Context.MkEq(
z3Context.MkIntConst(varList[i]),
z3Context.MkIntConst(varList[j])
)
)
);
}
}
}
