/// <summary>
/// Connect outgoing condition edges from parentBlock with belonging children point blocks via assume blocks
/// </summary>
/// <param name="parentBlock">Parent point block which children point blocks will be connected</param>
/// <param name="pendingBlocks">Point blocks which children hasn't been processed yet</param>
private void connectConditionEdges(PointsBlock parentBlock, Queue <PointsBlock> pendingBlocks)
{
//collected expression values - because of sharing with default branch
var expressionValues = new List <ValuePoint>();
//collected expression parts - because of default assumption condition creation
var expressionParts = new List <Expression>();
//collected expression blocks - because of connecting default assumption
var expressionBlocks = new List <PointsBlock>();
//process all outgoing conditional edges
// For each conditional edge, create block and append it as a child of parrent block
// TODO: in current CFG, there should be always at most one conditional edge
foreach (var edge in parentBlock.ConditionalEdges)
{
Expression expression;
if (edge.EdgeType == BasicBlockEdgeTypes.CONDITIONAL)
{
expression = edge.Condition;
}
else if (edge.EdgeType == BasicBlockEdgeTypes.FOREACH)
{
//now is foreach handled without condition processing (edge is added as non conditional)
connectConditionLessEdge(parentBlock, edge.To, pendingBlocks);
continue;
}
else
{
throw new NotSupportedException("Not supported CFG edge of type: " + edge.GetType());
}
var conditionExpressionBlock = _context.CreateFromExpression(expression);
var expressionValue = conditionExpressionBlock.LastPoint as ValuePoint;
//collect info for default branch
expressionValues.Add(expressionValue);
expressionParts.Add(expression);
expressionBlocks.Add(conditionExpressionBlock);
var condition = new AssumptionCondition(ConditionForm.All, expression);
parentBlock.AddChild(conditionExpressionBlock);
//connect edge.To through assume block
var assumeBlock = _context.CreateAssumeBlock(condition, edge.To, expressionValue);
conditionExpressionBlock.AddChild(assumeBlock);
//assume block needs processing of its children
pendingBlocks.Enqueue(assumeBlock);
}
//if there is default branch
if (parentBlock.Default != null)
{
if (expressionValues.Count == 0)
{
//there is default branch without any condition - connect without assume block
// connect default branch to parent
var defaultBlock = getChildBlock(parentBlock.Default, pendingBlocks);
//default block needs processing of its children
parentBlock.AddChild(defaultBlock);
}
else
{
//there has to be assumption condition on default branch
// connect default branch to conditional blocks
var values = expressionValues.ToArray();
var condition = new AssumptionCondition(ConditionForm.None, expressionParts.ToArray());
var defaultAssumeBlock = _context.CreateAssumeBlock(condition, parentBlock.Default, values);
//default Assume has to be added as child of all expression blocks
foreach (var conditionExpression in expressionBlocks)
{
conditionExpression.AddChild(defaultAssumeBlock);
}
pendingBlocks.Enqueue(defaultAssumeBlock);
}
}
}
/// <summary>
/// Connect outgoing condition less edge from parentBlock with given child
/// </summary>
/// <param name="parentBlock">Parent point block which child block will be connected</param>
/// <param name="child">Block connected as child of parent block</param>
/// <param name="pendingBlocks">Point blocks which children hasn't been processed yet</param>
private void connectConditionLessEdge(PointsBlock parentBlock, BasicBlock child, Queue <PointsBlock> pendingBlocks)
{
var childBlock = getChildBlock(child, pendingBlocks);
parentBlock.AddChild(childBlock);
}