public PredictionContext getCachedContext(PredictionContext context)
{
if (sharedContextCache == null)
{
return(context);
}
lock (sharedContextCache)
{
PredictionContext.IdentityHashMap visited =
new PredictionContext.IdentityHashMap();
return(PredictionContext.GetCachedContext(context,
sharedContextCache,
visited));
}
}
private static PredictionContext AppendContext(PredictionContext context, PredictionContext suffix, PredictionContext.IdentityHashMap visited)
{
if (suffix.IsEmpty)
{
if (IsEmptyLocal(suffix))
{
if (context.HasEmpty)
{
return(EmptyLocal);
}
throw new NotSupportedException("what to do here?");
}
return(context);
}
if (suffix.Size != 1)
{
throw new NotSupportedException("Appending a tree suffix is not yet supported.");
}
PredictionContext result;
if (!visited.TryGetValue(context, out result))
{
if (context.IsEmpty)
{
result = suffix;
}
else
{
int parentCount = context.Size;
if (context.HasEmpty)
{
parentCount--;
}
PredictionContext[] updatedParents = new PredictionContext[parentCount];
int[] updatedReturnStates = new int[parentCount];
for (int i = 0; i < parentCount; i++)
{
updatedReturnStates[i] = context.GetReturnState(i);
}
for (int i_1 = 0; i_1 < parentCount; i_1++)
{
updatedParents[i_1] = AppendContext(context.GetParent(i_1), suffix, visited);
}
if (updatedParents.Length == 1)
{
result = new SingletonPredictionContext(updatedParents[0], updatedReturnStates[0]);
}
else
{
System.Diagnostics.Debug.Assert(updatedParents.Length > 1);
result = new Antlr4.Runtime.Atn.ArrayPredictionContext(updatedParents, updatedReturnStates);
}
if (context.HasEmpty)
{
result = PredictionContext.Join(result, suffix);
}
}
visited[context] = result;
}
return(result);
}
public static Antlr4.Runtime.Atn.PredictionContext GetCachedContext(Antlr4.Runtime.Atn.PredictionContext
context, ConcurrentDictionary <Antlr4.Runtime.Atn.PredictionContext, Antlr4.Runtime.Atn.PredictionContext
> contextCache, PredictionContext.IdentityHashMap visited)
{
if (context.IsEmpty)
{
return(context);
}
Antlr4.Runtime.Atn.PredictionContext existing;
if (visited.TryGetValue(context, out existing))
{
return(existing);
}
if (contextCache.TryGetValue(context, out existing))
{
visited[context] = existing;
return(existing);
}
bool changed = false;
Antlr4.Runtime.Atn.PredictionContext[] parents = new Antlr4.Runtime.Atn.PredictionContext
[context.Size];
for (int i = 0; i < parents.Length; i++)
{
Antlr4.Runtime.Atn.PredictionContext parent = GetCachedContext(context.GetParent(
i), contextCache, visited);
if (changed || parent != context.GetParent(i))
{
if (!changed)
{
parents = new Antlr4.Runtime.Atn.PredictionContext[context.Size];
for (int j = 0; j < context.Size; j++)
{
parents[j] = context.GetParent(j);
}
changed = true;
}
parents[i] = parent;
}
}
if (!changed)
{
existing = contextCache.GetOrAdd(context, context);
visited[context] = existing;
return(context);
}
// We know parents.length>0 because context.isEmpty() is checked at the beginning of the method.
Antlr4.Runtime.Atn.PredictionContext updated;
if (parents.Length == 1)
{
updated = new SingletonPredictionContext(parents[0], context.GetReturnState(0));
}
else
{
ArrayPredictionContext arrayPredictionContext = (ArrayPredictionContext)context;
updated = new ArrayPredictionContext(parents, arrayPredictionContext.returnStates
, context.cachedHashCode);
}
existing = contextCache.GetOrAdd(updated, updated);
visited[updated] = existing;
visited[context] = existing;
return(updated);
}
public static PredictionContext GetCachedContext(PredictionContext context, PredictionContextCache contextCache, PredictionContext.IdentityHashMap visited)
{
if (context.IsEmpty)
{
return(context);
}
PredictionContext existing = visited.Get(context);
if (existing != null)
{
return(existing);
}
existing = contextCache.Get(context);
if (existing != null)
{
visited.Put(context, existing);
return(existing);
}
bool changed = false;
PredictionContext[] parents = new PredictionContext[context.Size];
for (int i = 0; i < parents.Length; i++)
{
PredictionContext parent = GetCachedContext(context.GetParent(i), contextCache, visited);
if (changed || parent != context.GetParent(i))
{
if (!changed)
{
parents = new PredictionContext[context.Size];
for (int j = 0; j < context.Size; j++)
{
parents[j] = context.GetParent(j);
}
changed = true;
}
parents[i] = parent;
}
}
if (!changed)
{
contextCache.Add(context);
visited.Put(context, context);
return(context);
}
PredictionContext updated;
if (parents.Length == 0)
{
updated = EMPTY;
}
else if (parents.Length == 1)
{
updated = SingletonPredictionContext.Create(parents[0], context.GetReturnState(0));
}
else
{
ArrayPredictionContext arrayPredictionContext = (ArrayPredictionContext)context;
updated = new ArrayPredictionContext(parents, arrayPredictionContext.returnStates);
}
contextCache.Add(updated);
visited.Put(updated, updated);
visited.Put(context, updated);
return(updated);
}