private void LabelAssign()
{
if (Tokens.Count < 3)
{
return;
}
bool isSuccess = false;
Token t1 = Tokens.Pop();
Token t2 = Tokens.Pop();
Token t3 = Tokens.Pop();
if (t1.Type == TokenType.Register &&
t2.Type == TokenType.Operator &&
t2.Value == ":=" &&
t3.Type == TokenType.String)
{
if (Tokens.Peek().Type != TokenType.Semicolon)
{
Error("No semicolon in operation", t3);
}
else
{
Tokens.Pop();
byte r1 = Convert.ToByte(t1.Value);
BinaryCommand prevCmd = new AssignConstCommand(0, r1);
Program.Add(prevCmd);
BinaryCommand cmd = new AddNextConstCommand(r1, r1);
Program.Add(cmd);
Label label = Mapper.Labels.Contains(t3.Value) ? (Label)Mapper.Labels[t3.Value] : null;
LabelAddress address = new LabelAddress(label);
if (label == null)
{
Mapper.Unreferenced.Add(new KeyValuePair <string, LabelAddress>(t3.Value, address));
}
Program.Add(address);
isSuccess = true;
}
}
if (isSuccess)
{
return;
}
Tokens.Push(t3);
Tokens.Push(t2);
Tokens.Push(t1);
}
private void ConstantAssign()
{
if (Tokens.Count < 3)
{
return;
}
bool isSuccess = false;
Token t1 = Tokens.Pop();
Token t2 = Tokens.Pop();
Token t3 = Tokens.Pop();
if (t1.Type == TokenType.Register &&
t2.Type == TokenType.Operator &&
t2.Value == ":=" &&
t3.Type == TokenType.Literal)
{
if (Tokens.Peek().Type != TokenType.Semicolon)
{
Error("No semicolon in operation", t3);
}
else
{
Tokens.Pop();
byte r2 = Convert.ToByte(t1.Value);
byte r1 = Convert.ToByte(t3.Value);
BinaryCommand cmd = new AssignConstCommand(r1, r2);
Program.Add(cmd);
isSuccess = true;
}
}
if (isSuccess)
{
return;
}
Tokens.Push(t3);
Tokens.Push(t2);
Tokens.Push(t1);
}
