private void LoopCheck()
{
var graph = new Graph <Absy>(new HashSet <Tuple <Absy, Absy> >(atomicityLabels.Keys));
graph.AddSource(initialState);
graph.ComputeLoops();
var edgeToLoopHeader = new Dictionary <Tuple <Absy, Absy>, Block>();
foreach (Block header in graph.SortHeadersByDominance())
{
foreach (var source in graph.BackEdgeNodes(header))
{
edgeToLoopHeader[new Tuple <Absy, Absy>(source, header)] = header;
foreach (var node in graph.NaturalLoops(header, source))
{
if (node == header)
{
continue;
}
foreach (var pred in graph.Predecessors(node))
{
var edge = new Tuple <Absy, Absy>(pred, node);
if (edgeToLoopHeader.ContainsKey(edge))
{
continue;
}
edgeToLoopHeader[edge] = header;
}
}
}
}
var parentLoopHeader = new Dictionary <Block, Block>();
foreach (Block header in graph.Headers)
{
foreach (var pred in graph.Predecessors(header).Except(graph.BackEdgeNodes(header)))
{
var edge = new Tuple <Absy, Absy>(pred, header);
if (edgeToLoopHeader.ContainsKey(edge))
{
parentLoopHeader[header] = edgeToLoopHeader[edge];
break;
}
}
}
var yieldingLoopHeaders = new HashSet <Block>(graph.Headers.OfType <Block>()
.Where(header => civlTypeChecker.IsYieldingLoopHeader(header, currLayerNum)));
foreach (var header in parentLoopHeader.Keys)
{
var parentHeader = parentLoopHeader[header];
if (yieldingLoopHeaders.Contains(header) && !yieldingLoopHeaders.Contains(parentHeader))
{
civlTypeChecker.Error(parentHeader,
$"Loop header must be yielding at layer {currLayerNum}");
}
}
foreach (var edge in edgeToLoopHeader.Keys)
{
var header = edgeToLoopHeader[edge];
if (yieldingLoopHeaders.Contains(header))
{
continue;
}
if (atomicityLabels[edge] == Y)
{
civlTypeChecker.Error(header,
$"Loop header must be yielding at layer {currLayerNum}");
}
}
}
