public int Visit(BinaryOperationNode node)
{
var left = node.Left.Accept(this);
var right = node.Right.Accept(this);
if ("+".Equals(node.Value))
{
return(left + right);
}
else
if ("-".Equals(node.Value))
{
return(left - right);
}
else
if ("*".Equals(node.Value))
{
return(left * right);
}
else
if ("/".Equals(node.Value))
{
return(left / right);
}
return(0);
}
public string Comparator(BinaryOperationNode bnode, Dictionary <string, int> variableIndex)
{
string instructions = converter.ConvertToCode(StandardBinaryOperation(bnode, variableIndex));
string zeroFlag = converter.ConvertToCode("cmp eax, ecx", "lahf", "shr eax, 14", "and eax, 1");
string signFlag = converter.ConvertToCode("cmp eax, ecx", "lahf", "shr eax, 15", "and eax, 1");
string comb = zeroFlag + converter.ConvertToCode("mov edx, eax", "lahf", "shr eax, 14", "and eax, 1");
string op = "";
string negate = converter.ConvertToCode("not eax", "and eax, 1");
switch (bnode.operation)
{
case "==": op = zeroFlag; break;
case "<": op = signFlag; break;
case "<=": op = comb; break;
case "!=": op = zeroFlag + negate; break;
case ">=": op = signFlag + negate; break;
case ">": op = comb + negate; break;
default: throw new Exception("Comparator " + bnode.operation + " is not being converted.");
}
return(instructions + op);
}
public AbstractSyntaxTreeNode Expr()
{
var result = Term();
while ("+".Equals(currentToken.Value) || "-".Equals(currentToken.Value))
{
var token = currentToken;
result = new BinaryOperationNode(result, Term(), token);
}
return(result);
}
private AbstractSyntaxTreeNode Term()
{
var result = Factor();
currentToken = lexer.NextToken();
while ("*".Equals(currentToken.Value) || "/".Equals(currentToken.Value))
{
var token = currentToken;
result = new BinaryOperationNode(result, Factor(), token);
currentToken = lexer.NextToken();
}
return(result);
}
public string BasicBinaryOperationNode(BinaryOperationNode bnode, Dictionary <string, int> variableIndex)
{
string op = null;
if (comparators.Contains(bnode.operation))
{
return(Comparator(bnode, variableIndex));
}
switch (bnode.operation)
{
case "+": op = "add"; break;
case "-": op = "sub"; break;
case "*": op = "imul"; break;
}
return(StandardBinaryOperation(bnode, variableIndex) + converter.ConvertToCode(op + " eax, ecx"));
}
public type GetType(BinaryOperationNode bon, Environment env)
{
type t1 = GetType(bon.left, env);
type t2 = GetType(bon.right, env);
if (bon.operation == "==")
{
return(new BoolType());
}
if (ExpressionMatches(t1, t2))
{
if (t1 is FixedType && !(t2 is FixedType))
{
return(t2);
}
return(t1);
}
throw new Exception("type mismatch" + bon.ToString());
}
public string StandardBinaryOperation(BinaryOperationNode bnode, Dictionary <string, int> variableIndex)
{
return(converter.ConvertToCode(converter.Convert(bnode.right, variableIndex), "push eax"
, converter.Convert(bnode.left, variableIndex), "pop ecx"));
}
public string Print(BinaryOperationNode bnode)
{
return("(" + Print(bnode.left) + ")"
+ bnode.operation + "(" + Print(bnode.right) + ")");
}