protected DataElement.Ctrl CreateOperator(string operation)
{
// try to re-use existing operator symbol
if (_usedOperators.ContainsKey(operation))
{
return(_usedOperators[operation]);
}
var op = new DataElement.Ctrl(_dataSet.CreateScriptValue(operation));
_usedOperators[operation] = op;
return(op);
}
public void Visit(BlockStmt stmt)
{
var start = EmitBlockStart();
foreach (var statement in stmt.Statements)
{
// emit instructions for this statement
statement.Accept(this);
// all locals should be freed at the end of each statement
Debug.Assert(!_usedLocals.ContainsValue(true), "Local not freed after statement evaluation");
}
EmitBlockEnd(start);
BlockStart = start;
}
public DataElement.Ctrl CreateLabel(string name, string idString = null, string linkString = null)
{
if (!int.TryParse(idString, out int id))
{
id = -1;
}
if (!int.TryParse(linkString, out int link))
{
link = -1;
}
if (Format.Yks.BlockLabels.Contains(name))
{
// create new label
var label = new DataElement.Ctrl(CreateScriptValue(name))
{
Id = id
};
if (id == -1 || link == -1)
{
throw new FormatException($"Block label must specify an id and a link: ':{id}:{name} [{link}]'");
}
// register label
Debug.Assert(!BlockLabels.ContainsKey(id), $"Duplicate label id: ':{id}:{name} [{link}]'");
BlockLabels[id] = label;
// try to link block start and end
if (BlockLabels.ContainsKey(link))
{
LinkLabels(BlockLabels[link], label);
}
return(label);
}
else
{
DataElement.Ctrl label;
if (!UniqueLabels.ContainsKey(name))
{
// register new unique label
// may be caused by a reference instead of the
// label declaration (-> don't set id here)
label = new DataElement.Ctrl(CreateScriptValue(name));
UniqueLabels[name] = label;
}
else
{
label = UniqueLabels[name];
}
// set id on label declaration only
if (id != -1)
{
label.Id = id;
}
if (link == -1)
{
return(label);
}
// link the label to itself
Debug.Assert(link == id, $"Unique label must link to itself: ':{id}:{name} [{link}]'");
label.LinkedElement = label;
return(label);
}
}
public void LinkLabels(DataElement.Ctrl a, DataElement.Ctrl b)
{
a.LinkedElement = b;
b.LinkedElement = a;
}
protected void EmitBlockEnd(DataElement.Ctrl start)
{
var end = EmitLabel("}");
LinkLabels(start, end);
}
protected void LinkLabels(DataElement.Ctrl a, DataElement.Ctrl b)
{
a.LinkedElement = b;
b.LinkedElement = a;
}
public LabelInstruction(DataElement.Ctrl label, InstructionList instructionList) : base(instructionList)
{
Label = label;
}
