public string Visit(NExprRel nExprRel)
{
string retVal = "";
if (nExprRel.children.Count == 2)
{
string pushTrueValue = GenerateLabel();
string pushFalseValue = GenerateLabel();
string exitExpression = GenerateLabel();
if (nExprRel.AnchorToken.Lexeme == "<")
{
retVal += Visit((dynamic)nExprRel[0]);
retVal += Visit((dynamic)nExprRel[1]);
retVal += "\t\tclt\n";
retVal += "\t\tbrtrue " + pushTrueValue + "\n";
retVal += "\t\tbr " + pushFalseValue + "\n";
}
else if (nExprRel.AnchorToken.Lexeme == "<=")
{
retVal += Visit((dynamic)nExprRel[0]);
retVal += Visit((dynamic)nExprRel[1]);
retVal += "\t\tcgt\n";
retVal += "\t\tldc.i4.0\n";
retVal += "\t\tceq\n";
retVal += "\t\tbrtrue " + pushTrueValue + "\n";
retVal += "\t\tbr " + pushFalseValue + "\n";
}
else if (nExprRel.AnchorToken.Lexeme == ">")
{
retVal += Visit((dynamic)nExprRel[0]);
retVal += Visit((dynamic)nExprRel[1]);
retVal += "\t\tcgt\n";
retVal += "\t\tbrtrue " + pushTrueValue + "\n";
retVal += "\t\tbr " + pushFalseValue + "\n";
}
else if (nExprRel.AnchorToken.Lexeme == ">=")
{
retVal += Visit((dynamic)nExprRel[0]);
retVal += Visit((dynamic)nExprRel[1]);
retVal += "\t\tclt\n";
retVal += "\t\tldc.i4.0\n";
retVal += "\t\tceq\n";
retVal += "\t\tbrtrue " + pushTrueValue + "\n";
retVal += "\t\tbr " + pushFalseValue + "\n";
}
retVal += pushTrueValue + ":\n";
retVal += "\t\tldc.i8 1\n";
retVal += "\t\tbr " + exitExpression + "\n";
retVal += pushFalseValue + ":\n";
retVal += "\t\tldc.i8 0\n";
retVal += exitExpression + ":\n";
}
else
{
retVal += Visit((dynamic)nExprRel[0]);
}
return(retVal);
}
// Returns NExprRel or any of subproduction nodes
public Node ExprRel()
{
Node resultingNode = ExprBitOr();
while (CurrentToken == TokenCategory.LESS_THAN || CurrentToken == TokenCategory.LESS_OR_EQUAL_THAN || CurrentToken == TokenCategory.GREATER_THAN || CurrentToken == TokenCategory.GREATER_OR_EQUAL_THAN)
{
NExprRel tmp = new NExprRel();
tmp.Add(resultingNode);
resultingNode = tmp;
switch (CurrentToken)
{
case TokenCategory.LESS_THAN: {
resultingNode.AnchorToken = Expect(TokenCategory.LESS_THAN);
resultingNode.Add(ExprBitOr());
break;
}
case TokenCategory.LESS_OR_EQUAL_THAN: {
resultingNode.AnchorToken = Expect(TokenCategory.LESS_OR_EQUAL_THAN);
resultingNode.Add(ExprBitOr());
break;
}
case TokenCategory.GREATER_THAN: {
resultingNode.AnchorToken = Expect(TokenCategory.GREATER_THAN);
resultingNode.Add(ExprBitOr());
break;
}
case TokenCategory.GREATER_OR_EQUAL_THAN: {
resultingNode.AnchorToken = Expect(TokenCategory.GREATER_OR_EQUAL_THAN);
resultingNode.Add(ExprBitOr());
break;
}
}
}
return(resultingNode);
}
//------------------------------------------------------------
public void Visit(NExprRel node)
{
Console.WriteLine($"+++++++++++++++ NExprRel ++++++++++++++++");
//VisitChildren(node);
}
public void Visit(NExprRel nExprRel)
{
GenericChildVisitor(nExprRel);
}