private void Use(Expression expr, Statement stm)
{
ExpressionUseAdder eua = new ExpressionUseAdder(stm, ssaIds);
expr.Accept(eua);
}
public void UseExpression(Expression exp)
{
if (Statement == null)
return;
var xu = new ExpressionUseAdder(Statement, ssaIds);
exp.Accept(xu);
}