private void PushComparison(Expression lhs, Expression rhs, ComparisonOperator op)
{
Visit(lhs);
object left = Pop();
Visit(rhs);
object right = Pop();
bool areOperandsSwapped = IsCandidateFieldValue(right);
if (areOperandsSwapped)
{
object temp = left;
left = right;
right = temp;
}
AssertType(left, typeof(FieldValue), lhs);
AssertType(right, typeof(IComparisonOperand), rhs);
Push(new ComparisonExpression((FieldValue)left, (IComparisonOperand)right, op));
if (areOperandsSwapped && !op.IsSymmetric())
{
Negate();
}
}