/// <summary>
/// Main method of merge algorithm.
///
/// in first phase prepares new empty structure and data collections. Then collects all root memory locations
/// and prepares their operations. As the final step process all merge operations which traverses the memory tree
/// and creates new memory locations in target structure with the data from all source indexes.
/// </summary>
internal void Merge()
{
ContainerOperations[] collectVariables = new ContainerOperations[targetSnapshot.CallLevel + 1];
ContainerOperations[] collectControl = new ContainerOperations[targetSnapshot.CallLevel + 1];
MergeOperation returnOperation = new MergeOperation();
// Prepares empty structure for target snapshot
for (int x = 0; x <= targetSnapshot.CallLevel; x++)
{
IndexContainer variables = new IndexContainer(VariableIndex.CreateUnknown(x));
Structure.Variables[x] = variables;
collectVariables[x] = new ContainerOperations(this, variables, variables.UnknownIndex, variables.UnknownIndex);
IndexContainer control = new IndexContainer(ControlIndex.CreateUnknown(x));
Structure.ContolVariables[x] = control;
collectControl[x] = new ContainerOperations(this, control, control.UnknownIndex, control.UnknownIndex);
Structure.Temporary[x] = new IndexSet <TemporaryIndex>();
Structure.Arrays[x] = new IndexSet <AssociativeArray>();
}
// Collects all objects and root locations from the source objects
foreach (Snapshot snapshot in sourceSnapshots)
{
collectObjects(snapshot);
for (int sourceLevel = 0, targetLevel = 0; targetLevel <= targetSnapshot.CallLevel; sourceLevel++, targetLevel++)
{
// Local levels of snaphot has to be merged together no matter to call level of each snapshot.
if (sourceLevel == snapshot.CallLevel && snapshot.CallLevel != targetSnapshot.CallLevel)
{
if (isCallMerge)
{
// When this is the call merge the local level is forgotten
break;
}
else
{
targetLevel = targetSnapshot.CallLevel;
}
}
// Gets all root locations
collectVariables[targetLevel].CollectIndexes(snapshot, Structure.Variables[targetLevel].UnknownIndex, snapshot.Structure.Variables[sourceLevel]);
collectControl[targetLevel].CollectIndexes(snapshot, Structure.ContolVariables[targetLevel].UnknownIndex, snapshot.Structure.ContolVariables[sourceLevel]);
collectTemporary(snapshot, sourceLevel, targetLevel);
}
mergeDeclarations(Structure.FunctionDecl, snapshot.Structure.FunctionDecl);
mergeDeclarations(Structure.ClassDecl, snapshot.Structure.ClassDecl);
// When is it call merge remember which arrays was forgotten in order to support arrays in returns
if (isCallMerge)
{
foreach (AssociativeArray array in snapshot.Structure.Arrays.Local)
{
Structure.AddCallArray(array, snapshot);
}
}
}
mergeObjects();
// Prepares operations for all root locations
for (int x = 0; x <= targetSnapshot.CallLevel; x++)
{
collectVariables[x].MergeContainers();
collectControl[x].MergeContainers();
mergeTemporary(x);
}
processMerge();
// Build aliases
foreach (var alias in memoryAliases)
{
Structure.SetAlias(alias.Key, alias.Value.Build());
}
}