private void AddPotentialHandlerSuccessors(
ICollection <ControlFlowNode <TInstruction> > result,
ControlFlowNode <TInstruction> node)
{
var ehRegion = node.GetParentExceptionHandler();
while (ehRegion is {})
private IReadOnlyList <ControlFlowNode <TInstruction> > ChildrenLister(ControlFlowNode <TInstruction> node)
{
// NOTE: Order of the resulting list is important.
// We want to prioritize normal edges over abnormal edges and exception handlers.
var visited = new HashSet <ControlFlowNode <TInstruction> >();
var result = new List <ControlFlowNode <TInstruction> >();
// Add fallthrough.
if (node.FallThroughNeighbour is {} neighbour)
{
result.Add(neighbour);
visited.Add(neighbour);
}
// Conditional edges.
foreach (var edge in node.ConditionalEdges)
{
var target = edge.Target;
if (visited.Add(target))
{
result.Add(target);
}
}
// Abnormal edges.
foreach (var edge in node.AbnormalEdges)
{
var target = edge.Target;
if (visited.Add(target))
{
result.Add(target);
}
}
// Check if any exception handler might catch an error within this node.
var ehRegion = node.GetParentExceptionHandler();
while (ehRegion is {})
private void AddPotentialHandlerSuccessors(
ICollection <ControlFlowNode <TInstruction> > result,
ControlFlowNode <TInstruction> node)
{
// If the node is in an exception handler, here are a couple of "implicit" successors.
//
// - Any node in the protected region has an implicit successor to the start of every handler region.
//
// - Any node in a prologue/body/epilogue of a handler region has an implicit successor of the next
// embedded region. That is, a prologue node can transfer control to the body, and body to epilogue.
//
// - Any node in a handler region also implicitly can transfer control to one of the successors of any
// node in the protected region (e.g. a try-finally construct does not have explicit outgoing branches).
//
// These successors are not explicitly encoded as an edge in the input CFG, but do often matter
// when it comes to ordering these nodes (e.g. CIL requires handlers to be after the protected region).
// Therefore, we add these as "virtual" successors to the list, to ensure the topological sorting
// takes this into account.
var ehRegion = node.GetParentExceptionHandler();
while (ehRegion is { })
