private Expression VisitVariable(ParameterExpression node, ExpressionAccess access)
{
ParameterExpression boxStorage;
if (!this._loopLocals.Contains(node))
{
LoopVariable variable;
LocalVariable variable2;
if (this._loopVariables.TryGetValue(node, out variable))
{
boxStorage = variable.BoxStorage;
this._loopVariables[node] = new LoopVariable(variable.Access | access, boxStorage);
goto Label_00A5;
}
if (this._outerVariables.TryGetValue(node, out variable2) || ((this._closureVariables != null) && this._closureVariables.TryGetValue(node, out variable2)))
{
boxStorage = variable2.InClosureOrBoxed ? Expression.Parameter(typeof(StrongBox <object>), node.Name) : null;
this._loopVariables[node] = new LoopVariable(access, boxStorage);
goto Label_00A5;
}
}
return(node);
Label_00A5:
if (boxStorage == null)
{
return(node);
}
if ((access & ExpressionAccess.Write) != ExpressionAccess.None)
{
return(LightCompiler.Unbox(boxStorage));
}
return(Expression.Convert(LightCompiler.Unbox(boxStorage), node.Type));
}
private Expression VisitVariable(ParameterExpression node, ExpressionAccess access)
{
ParameterExpression box;
LoopVariable existing;
LocalVariable loc;
if (_loopLocals.Contains(node))
{
// local to the loop - not propagated in or out
return(node);
}
else if (_loopVariables.TryGetValue(node, out existing))
{
// existing outer variable that we are already tracking
box = existing.BoxStorage;
_loopVariables[node] = new LoopVariable(existing.Access | access, box);
}
else if (_outerVariables.TryGetValue(node, out loc) ||
(_closureVariables != null && _closureVariables.TryGetValue(node, out loc)))
{
// not tracking this variable yet, but defined in outer scope and seen for the 1st time
box = loc.InClosureOrBoxed ? Expression.Parameter(typeof(StrongBox <object>), node.Name) : null;
_loopVariables[node] = new LoopVariable(access, box);
}
else
{
// node is a variable defined in a nested lambda -> skip
return(node);
}
if (box != null)
{
if ((access & ExpressionAccess.Write) != 0)
{
// compound assignments were reduced:
Debug.Assert((access & ExpressionAccess.Read) == 0);
// box.Value = (object)rhs
return(LightCompiler.Unbox(box));
}
else
{
// (T)box.Value
return(Expression.Convert(LightCompiler.Unbox(box), node.Type));
}
}
return(node);
}
private Expression VisitVariable(ParameterExpression node, ExpressionAccess access)
{
ParameterExpression box;
LoopVariable existing;
LocalVariable loc;
if (_loopVariables.TryGetValue(node, out existing))
{
box = existing.BoxStorage;
_loopVariables[node] = new LoopVariable(existing.Access | access, box);
}
else if (_locals.TryGetLocal(node, out loc))
{
box = loc.InClosureOrBoxed ? Expression.Parameter(typeof(StrongBox <object>), node.Name) : null;
_loopVariables[node] = new LoopVariable(access, box);
}
else
{
// node is a variable defined in a nested lambda -> skip
return(node);
}
if (box != null)
{
if ((access & ExpressionAccess.Write) != 0)
{
// compound assignments were reduced:
Debug.Assert((access & ExpressionAccess.Read) == 0);
// box.Value = (object)rhs
return(LightCompiler.Unbox(box));
}
else
{
// (T)box.Value
return(Expression.Convert(LightCompiler.Unbox(box), node.Type));
}
}
return(node);
}
public LoopVariable(ExpressionAccess access, ParameterExpression box)
{
Access = access;
BoxStorage = box;
}
