public static Dictionary <Function, HashSet <List <VCExpr> > > CollectInstances(QuantifierInstantiationEngine qiEngine, VCExpr vcExpr)
{
var lambdaInstanceCollector = new LambdaInstanceCollector(qiEngine);
lambdaInstanceCollector.Traverse(vcExpr, true);
var lambdaFunctionToInstances =
lambdaInstanceCollector.lambdaFunctions.ToDictionary(
x => x, x => new HashSet <List <VCExpr> >(new ListComparer <VCExpr>()));
foreach (var instance in lambdaInstanceCollector.instances)
{
var function = (instance.Op as VCExprBoogieFunctionOp).Func;
lambdaFunctionToInstances[function].Add(instance.UniformArguments.ToList());
}
return(lambdaFunctionToInstances);
}
private VCExpr Execute(Implementation impl, VCExpr vcExpr)
{
impl.Blocks.ForEach(block => block.Cmds.OfType <PredicateCmd>().Iter(predicateCmd =>
{
AddDictionary(FindInstantiationSources(predicateCmd, "add_to_pool", exprTranslator), labelToInstances);
}));
vcExpr = Skolemizer.Skolemize(this, Polarity.Negative, vcExpr);
lambdaToInstances = LambdaInstanceCollector.CollectInstances(this, vcExpr);
while (labelToInstances.Count > 0)
{
var currLabelToInstances = labelToInstances;
labelToInstances = new Dictionary <string, HashSet <VCExpr> >();
AddDictionary(currLabelToInstances, accLabelToInstances);
var currLambdaToInstances = lambdaToInstances;
lambdaToInstances = new Dictionary <Function, HashSet <List <VCExpr> > >();
AddDictionary(currLambdaToInstances, accLambdaToInstances);
var visitedQuantifierBindings = new HashSet <VCExprVar>();
while (visitedQuantifierBindings.Count < quantifierBinding.Count)
{
foreach (var v in quantifierBinding.Keys)
{
if (visitedQuantifierBindings.Contains(v))
{
continue;
}
visitedQuantifierBindings.Add(v);
var quantifierExpr = quantifierBinding[v];
var quantifierInfo = quantifierInstantiationInfo[quantifierExpr];
if (quantifierInfo.relevantLabels.Overlaps(currLabelToInstances.Keys))
{
InstantiateQuantifier(quantifierExpr);
}
}
}
var visitedLambdaFunctions = new HashSet <Function>();
while (visitedLambdaFunctions.Count < lambdaDefinition.Count)
{
foreach (var lambdaFunction in lambdaDefinition.Keys)
{
if (visitedLambdaFunctions.Contains(lambdaFunction))
{
continue;
}
visitedLambdaFunctions.Add(lambdaFunction);
var quantifierExpr = lambdaDefinition[lambdaFunction];
var quantifierInfo = quantifierInstantiationInfo[quantifierExpr];
if (quantifierInfo.relevantLabels.Overlaps(currLabelToInstances.Keys) ||
currLambdaToInstances[lambdaFunction].Count > 0)
{
InstantiateLambdaDefinition(lambdaFunction);
}
}
}
}
var lambdaAxioms = vcExprGen.NAry(VCExpressionGenerator.AndOp, lambdaDefinition.Values
.SelectMany(quantifierExpr =>
quantifierInstantiationInfo[quantifierExpr].instances.Values.ToList()).ToList());
return(vcExprGen.Implies(lambdaAxioms, LetConvert(vcExpr)));
}
