PHPCfg\Op::addReadRef PHP Method

    protected function addReadRef($op)
    {
        if (is_array($op)) {
            $new = [];
            foreach ($op as $key => $o) {
                $new[$key] = $this->addReadRef($o);
            }
            return $new;
        } elseif (!$op instanceof Operand) {
            return $op;
        }
        return $op->addUsage($this);
    }