/// <summary>
/// Processes single merge operation - prepares all valid values and alias informations from the source indexes.
/// When the source indexes contains some array values prepares operation for every descendant index and merge the
/// array into one which will be stored in the target memory entry.
/// </summary>
/// <param name="operation">The operation.</param>
private void processMergeOperation(MergeOperation operation)
{
CollectComposedValuesVisitor visitor = new CollectComposedValuesVisitor();
ReferenceCollector references = new ReferenceCollector();
// Collect all data from source indexes
foreach (var operationData in operation.Indexes)
{
MemoryIndex index = operationData.Item1;
Snapshot snapshot = operationData.Item2;
MemoryEntry entry = snapshot.Structure.GetMemoryEntry(index);
visitor.VisitMemoryEntry(entry);
MemoryAlias aliases;
if (snapshot.Structure.TryGetAliases(index, out aliases))
{
references.CollectMust(aliases.MustAliasses, targetSnapshot.CallLevel);
references.CollectMay(aliases.MayAliasses, targetSnapshot.CallLevel);
}
else
{
references.InvalidateMust();
}
}
references.SetAliases(operation.TargetIndex, this, !operation.IsUndefined);
//repares the set of values - array values are traversed
HashSet <Value> values = getValues(operation, visitor);
// If some index in operation can be undefined add undefined value into result
if (operation.IsUndefined)
{
values.Add(targetSnapshot.UndefinedValue);
}
Structure.SetMemoryEntry(operation.TargetIndex, new MemoryEntry(values));
Structure.SetObjects(operation.TargetIndex, new ObjectValueContainer(visitor.Objects));
}
private void processMergeOperation(MergeOperation operation)
{
CollectComposedValuesVisitor visitor = new CollectComposedValuesVisitor();
ReferenceCollector references = new ReferenceCollector();
foreach (var item in operation.Indexes)
{
Snapshot snapshot = item.Item2;
MemoryIndex index = item.Item1;
MemoryEntry entry = snapshot.Structure.GetMemoryEntry(index);
visitor.VisitMemoryEntry(entry);
MemoryAlias aliases;
if (snapshot.Structure.TryGetAliases(index, out aliases))
{
references.CollectMust(aliases.MustAliasses, snapshot.CallLevel);
references.CollectMay(aliases.MayAliasses, snapshot.CallLevel);
}
else
{
references.InvalidateMust();
}
}
if (references.HasAliases && !operation.IsRoot)
{
if (!operation.IsUndefined && operation.Indexes.Count == 1 && references.HasMustAliases)
{
if (targetSnapshot == operation.Indexes.First().Item2)
{
references.AddMustAlias(operation.Indexes.First().Item1);
}
}
else
{
HashSet <MemoryIndex> referenceIndexes = new HashSet <MemoryIndex>();
foreach (var item in operation.Indexes)
{
MemoryIndex index = item.Item1;
Snapshot snapshot = item.Item2;
if (index != operation.TargetIndex && targetSnapshot == snapshot)
{
referenceIndexes.Add(index);
}
}
references.CollectMay(referenceIndexes, targetSnapshot.CallLevel);
}
}
references.SetAliases(operation.TargetIndex, targetSnapshot, !operation.IsUndefined);
HashSet <Value> values = getValues(operation.TargetIndex, visitor, operation.IsUndefined);
if (operation.IsUndefined)
{
values.Add(targetSnapshot.UndefinedValue);
}
targetSnapshot.Structure.SetMemoryEntry(operation.TargetIndex, new MemoryEntry(values));
}
