ILExpression MakeGoTo(LabelRangeMapping mapping, int state)
{
foreach (var pair in mapping)
{
if (pair.Value.Contains(state))
{
return(new ILExpression(ILCode.Br, pair.Key));
}
}
throw new SymbolicAnalysisFailedException();
}
void CreateLabelRangeMapping(List<ILNode> body, int pos, int bodyLength, LabelRangeMapping result, bool onlyInitialLabels)
{
for (int i = pos; i < bodyLength; i++) {
ILLabel label = body[i] as ILLabel;
if (label != null) {
result.Add(new KeyValuePair<ILLabel, StateRange>(label, ranges[label]));
} else {
ILTryCatchBlock tryCatchBlock = body[i] as ILTryCatchBlock;
if (tryCatchBlock != null) {
CreateLabelRangeMapping(tryCatchBlock.TryBlock.Body, 0, tryCatchBlock.TryBlock.Body.Count, result, true);
} else if (onlyInitialLabels) {
break;
}
}
}
}
List<ILNode> ConvertBody(List<ILNode> body, int startPos, int bodyLength, LabelRangeMapping mapping)
{
List<ILNode> newBody = new List<ILNode>();
// Copy all instructions from the old body to newBody.
for (int pos = startPos; pos < bodyLength; pos++) {
ILTryCatchBlock tryCatchBlock = body[pos] as ILTryCatchBlock;
ILExpression expr = body[pos] as ILExpression;
if (expr != null && expr.Code == ILCode.Leave && expr.Operand == exitLabel) {
ILVariable awaiterVar;
FieldDef awaiterField;
int targetStateID;
HandleAwait(newBody, out awaiterVar, out awaiterField, out targetStateID);
MarkAsGeneratedVariable(awaiterVar);
newBody.Add(new ILExpression(ILCode.Await, null, new ILExpression(ILCode.Ldloca, awaiterVar)));
newBody.Add(MakeGoTo(mapping, targetStateID));
} else if (tryCatchBlock != null) {
ILTryCatchBlock newTryCatchBlock = new ILTryCatchBlock();
var tryBody = tryCatchBlock.TryBlock.Body;
if (tryBody.Count == 0)
throw new SymbolicAnalysisFailedException();
StateRangeAnalysis rangeAnalysis = new StateRangeAnalysis(tryBody[0], StateRangeAnalysisMode.AsyncMoveNext, stateField, cachedStateVar);
int tryBodyLength = tryBody.Count;
int posInTryBody = rangeAnalysis.AssignStateRanges(tryBody, tryBodyLength);
rangeAnalysis.EnsureLabelAtPos(tryBody, ref posInTryBody, ref tryBodyLength);
var mappingInTryBlock = rangeAnalysis.CreateLabelRangeMapping(tryBody, posInTryBody, tryBodyLength);
var newTryBody = ConvertBody(tryBody, posInTryBody, tryBodyLength, mappingInTryBlock);
newTryBody.Insert(0, MakeGoTo(mappingInTryBlock, initialState));
// If there's a label at the beginning of the state dispatcher, copy that
if (posInTryBody > 0 && tryBody.FirstOrDefault() is ILLabel)
newTryBody.Insert(0, tryBody.First());
newTryCatchBlock.TryBlock = new ILBlock(newTryBody);
newTryCatchBlock.CatchBlocks = new List<ILTryCatchBlock.CatchBlock>(tryCatchBlock.CatchBlocks);
newTryCatchBlock.FaultBlock = tryCatchBlock.FaultBlock;
if (tryCatchBlock.FinallyBlock != null)
newTryCatchBlock.FinallyBlock = new ILBlock(ConvertFinally(tryCatchBlock.FinallyBlock.Body));
newBody.Add(newTryCatchBlock);
} else {
newBody.Add(body[pos]);
}
}
return newBody;
}
ILExpression MakeGoTo(LabelRangeMapping mapping, int state)
{
foreach (var pair in mapping) {
if (pair.Value.Contains(state))
return new ILExpression(ILCode.Br, pair.Key);
}
throw new SymbolicAnalysisFailedException();
}
List<ILNode> ConvertBody(List<ILNode> body, int startPos, int bodyLength, LabelRangeMapping mapping)
{
List<ILNode> newBody = new List<ILNode>();
// Copy all instructions from the old body to newBody.
for (int pos = startPos; pos < bodyLength; pos++) {
ILTryCatchBlock tryCatchBlock = body[pos] as ILTryCatchBlock;
ILExpression expr = body[pos] as ILExpression;
if (expr != null && expr.Code == ILCode.Leave && expr.Operand == exitLabel) {
ILVariable awaiterVar;
FieldDef awaiterField;
int targetStateID;
HandleAwait(newBody, out awaiterVar, out awaiterField, out targetStateID);
MarkAsGeneratedVariable(awaiterVar);
newBody.Add(new ILExpression(ILCode.Await, null, new ILExpression(ILCode.Ldloca, awaiterVar)));
newBody.Add(MakeGoTo(mapping, targetStateID));
} else if (tryCatchBlock != null) {
ILTryCatchBlock newTryCatchBlock = new ILTryCatchBlock();
var tryBody = tryCatchBlock.TryBlock.Body;
if (tryBody.Count == 0)
throw new SymbolicAnalysisFailedException();
StateRangeAnalysis rangeAnalysis = new StateRangeAnalysis(tryBody[0], StateRangeAnalysisMode.AsyncMoveNext, stateField, cachedStateVar);
int tryBodyLength = tryBody.Count;
int posInTryBody = rangeAnalysis.AssignStateRanges(tryBody, tryBodyLength);
rangeAnalysis.EnsureLabelAtPos(tryBody, ref posInTryBody, ref tryBodyLength);
var mappingInTryBlock = rangeAnalysis.CreateLabelRangeMapping(tryBody, posInTryBody, tryBodyLength);
var newTryBody = ConvertBody(tryBody, posInTryBody, tryBodyLength, mappingInTryBlock);
newTryBody.Insert(0, MakeGoTo(mappingInTryBlock, initialState));
// If there's a label at the beginning of the state dispatcher, copy that
if (posInTryBody > 0 && tryBody.FirstOrDefault() is ILLabel)
newTryBody.Insert(0, tryBody.First());
newTryCatchBlock.TryBlock = new ILBlock(newTryBody);
newTryCatchBlock.CatchBlocks = new List<ILTryCatchBlock.CatchBlock>(tryCatchBlock.CatchBlocks);
newTryCatchBlock.FaultBlock = tryCatchBlock.FaultBlock;
if (tryCatchBlock.FinallyBlock != null)
newTryCatchBlock.FinallyBlock = new ILBlock(ConvertFinally(tryCatchBlock.FinallyBlock.Body));
newBody.Add(newTryCatchBlock);
} else {
newBody.Add(body[pos]);
}
}
return newBody;
}
public LabelRangeMapping CreateLabelRangeMapping(List<ILNode> body, int pos, int bodyLength)
{
LabelRangeMapping result = new LabelRangeMapping();
CreateLabelRangeMapping(body, pos, bodyLength, result, false);
return result;
}
