public override AstNode Visit(GotoCaseStatement node)
{
// Begin the node.
builder.BeginNode(node);
// Get the constant expression.
Expression constant = node.GetLabel();
// Expand it.
if(constant != null)
{
// Get the constant value.
IChelaType coercionType = node.GetCoercionType();
ConstantValue constantValue = (ConstantValue)constant.GetNodeValue();
constantValue = constantValue.Cast(coercionType);
// Make sure the case is in the current switch.
IDictionary<ConstantValue, CaseLabel> caseDict = node.GetSwitch().CaseDictionary;
CaseLabel targetLabel;
if(!caseDict.TryGetValue(constantValue, out targetLabel))
Error(node, "current switch doesn't contain a case for [{1}]{0}.", constantValue.ToString(), constantValue.GetHashCode());
node.SetTargetLabel(targetLabel);
}
// Jump to the target case.
CaseLabel targetCase = node.GetTargetLabel();
builder.CreateJmp(targetCase.GetBlock());
// End the node.
return builder.EndNode();
}
public override AstNode Visit(GotoCaseStatement node)
{
// Store the current switch in the node.
node.SetSwitch(currentSwitch);
// Get the constant expression.
Expression constant = node.GetLabel();
// Expand it.
CaseLabel targetLabel;
if(constant != null)
{
constant = (Expression)constant.Accept(this);
node.SetLabel(constant);
// Get the constant value.
IChelaType coercionType = currentSwitch.GetCoercionType();
node.SetCoercionType(coercionType);
}
else
{
// Make sure the current switch contains a default case.
targetLabel = currentSwitch.GetDefaultCase();
if(targetLabel == null)
Error(node, "current switch doesn't contain a default case.");
node.SetTargetLabel(targetLabel);
}
return node;
}
public override AstNode Visit(GotoCaseStatement node)
{
Expression labelConstant = node.GetLabel();
// This statement only can be used inside of a switch.
if(currentSwitch == null)
Error(node, "goto {0} only can be used inside of a switch.",
labelConstant == null ? "default" : "case");
// Coerce the label constant.
if(labelConstant != null)
{
// Visit the label expression.
labelConstant.Accept(this);
// Coerce the label expression.
IChelaType labelType = labelConstant.GetNodeType();
IChelaType coercionType = currentSwitch.GetCoercionType();
if(Coerce(node, coercionType, labelType, labelConstant.GetNodeValue()) != coercionType)
Error(node, "cannot implicitly cast a label of type {0} into {1}",
labelType.GetDisplayName(), coercionType.GetDisplayName());
// Not all of the cases have been registered yet, so perform the
// existence checks in generation pass.
}
// Remove dead code.
AstNode dead= node.GetNext();
if(dead != null)
Warning(dead, "detected unreachable code.");
node.SetNext(null);
return node;
}
