internal override void Accept(OperationVisitor visitor)
{
visitor.Visit(this);
}
public FlowReachability(FlowPoint entry, ControlFlowGraph graph, OperationVisitor <None, bool> suspensionPoint)
{
this.graph = graph;
if (!Belongs(entry))
{
throw new ArgumentException("Entry not belongs to graph");
}
reachable = new Lazy <HashSet <FlowPoint> >(
() =>
{
var visited = new HashSet <FlowPoint>();
var visitedRegions = new HashSet <ControlFlowRegion>();
var stack = new Stack <FlowPoint>();
stack.Push(entry);
while (stack.Count > 0)
{
var point = stack.Pop();
if (!visited.Add(point))
{
continue;
}
var region = point.Block.EnclosingRegion;
if (visitedRegions.Add(region))
{
var tries = region.Containing(ControlFlowRegionKind.Try).Take(1);
foreach (var @try in tries)
{
var parent = @try.EnclosingRegion;
if (parent.Kind == ControlFlowRegionKind.TryAndCatch)
{
if (visitedRegions.Add(parent))
{
var catchRegion = parent.NestedRegions[1];
var @catch = new FlowPoint(graph.Blocks[catchRegion.FirstBlockOrdinal]);
stack.Push(@catch);
}
}
else if (parent.Kind == ControlFlowRegionKind.TryAndFinally)
{
if (visitedRegions.Add(parent))
{
var finallyRegion = parent.NestedRegions[1];
var @finally = new FlowPoint(graph.Blocks[finallyRegion.FirstBlockOrdinal]);
stack.Push(@finally);
}
}
}
}
if (point.AtOperation)
{
var operation = point.Operation;
if (!suspensionPoint.Visit(operation))
{
stack.Push(point.Next);
}
continue;
}
if (point.Block.FallThroughSuccessor is { Destination: { } fallThrough })
{
stack.Push(new FlowPoint(fallThrough));
}
if (point.Block.ConditionalSuccessor is { Destination: { } conditional })
