Ternary select operator:
            name = cond ? lhs : rhs

def select(self, cond, lhs, rhs, name=''):
        """
        Ternary select operator:
            name = cond ? lhs : rhs
        """
        instr = instructions.SelectInstr(self.block, cond, lhs, rhs, name=name)
        self._insert(instr)
        return instr