private ActionBlock OnAssign(AssignActionBlock block)
{
var assign = block.AssignExpression;
var variable = assign.Target as VariableReferenceExpression;
if (variable == null)
{
CannotOptimize(assign);
}
if (HasBeenAlreadyAssignedTo(variable))
{
CannotOptimize(assign.Expression);
}
_variables.Add(GetVariableIndex(variable), assign.Expression);
return(block.Next);
}
private static Expression GetQueryExpression(ActionFlowGraph afg)
{
IDictionary <int, Expression> variables = new Dictionary <int, Expression>();
ActionBlock block = afg.Blocks[0];
while (block != null)
{
switch (block.ActionType)
{
case ActionType.Invoke:
InvokeActionBlock invokeBlock = (InvokeActionBlock)block;
MethodInvocationExpression invocation = invokeBlock.Expression;
if (IsActivateInvocation(invocation) ||
IsNoSideEffectIndirectActivationInvocation(invocation))
{
block = invokeBlock.Next;
break;
}
UnsupportedExpression(invocation);
break;
case ActionType.ConditionalBranch:
UnsupportedPredicate("Conditional blocks are not supported.");
break;
case ActionType.Branch:
block = ((BranchActionBlock)block).Target;
break;
case ActionType.Assign:
{
AssignActionBlock assignBlock = (AssignActionBlock)block;
AssignExpression assign = assignBlock.AssignExpression;
VariableReferenceExpression variable = assign.Target as VariableReferenceExpression;
if (null == variable)
{
UnsupportedExpression(assign);
}
else
{
if (variables.ContainsKey(variable.Variable.Index))
{
UnsupportedExpression(assign.Expression);
}
variables.Add(variable.Variable.Index, assign.Expression);
block = assignBlock.Next;
}
break;
}
case ActionType.Return:
{
Expression expression = ((ReturnActionBlock)block).Expression;
VariableReferenceExpression variable = expression as VariableReferenceExpression;
return(null == variable
? expression
: variables[variable.Variable.Index]);
}
}
}
return(null);
}
void WriteAssign(AssignActionBlock block)
{
WriteExpression(block.AssignExpression);
}