public OpcodeStream(ParseStream strm, ExecutionStack stack)
{
_jumpTable = new JumpTable();
opCodes = new ArrayList();
currentIP = new Stack();
Init(strm, stack);
}
public override void Execute(ExecutionEnvironment environment)
{
DemandArgs(2);
int offSet = environment.OpCodes.JumpTable.GetIndex(Arguments[0].Value.StringValue);
int argCount = Arguments[1].Value.IntegerValue;
LexicalScope ls = new LexicalScope(environment.GlobalScope);
ExecutionStack s = new ExecutionStack(ls);
if(argCount > 0)
{
ExecutionStackItem [] tmpItems = new ExecutionStackItem[argCount];
for(int i = 0; i < argCount; i++)
{
tmpItems[i] = environment.LocalStack.PopItem();
}
for(int i = argCount - 1; i >= 0; i--)
{
s.PushItem(tmpItems[i]);
}
}
environment.PushStack(s);
environment.OpCodes.PushCurrentIPAndSet(offSet);
}
private void Init(ParseStream strm, ExecutionStack stack)
{
InstructionPointer = 0;
Hashtable ocTypes = InitOpCodes();
while(true)
{
string word = null;
if(strm.ReadWord(ref word))
{
if(ocTypes.ContainsKey(word))
{
OpCode oc = OpCode.Create(ocTypes[word] as Type);
oc.Line = strm.CurrentLine;
if(oc != null)
{
bool addToOpcodes = true;
oc.ReadArguments(strm, stack.Scope);
if(oc.GetType().IsSubclassOf(typeof(LabelOpCode)))
{
string name = (oc as LabelOpCode).GetName();
JumpTable.AddIndex(name, opCodes.Count);
addToOpcodes = false;
}
if(addToOpcodes)
{
opCodes.Add(oc);
}
}
else
{
throw new ParseException( string.Format("Activate Opcode: {0}", word),
string.Format("Unable to activate Opcode: {0}", word));
}
}
else
{
throw new ParseException("Valid token", string.Format("Unexpected token found: {0}", word) );
}
}
else
{
break;
}
}
}
public void PushStack(ExecutionStack stack)
{
executionStacks.Push(stack);
}