Performance optimization ideas for PHP 7.3

Hello internals, During the last months, I've been working on optimizing Symfony/Twig for PHP7. I found a few situations where the PHP engine could likely be optimized, and where it would benefit real-world apps. In each case, these might look like micro-optimizations, but they are not in hot loops. Here are the links to issues I created in the php bug tracker: - Class constants are slow: they should be inlined at runtime - https://bugs.php.net/76178 - Add array_key_exists() to the list of specialy compiled functions - https://bugs.php.net/76148 - Don't trigger copy-on-write when assigning same value - https://bugs.php.net/76150 As a bonus, I also created this one today: - Add hrtime() to zend_try_compile_special_func() - https://bugs.php.net/76241 It would be awesome if those ideas could be implemented in a future PHP version. (I'm sorry I don't have the knowledge to do it myself.) Keep up the good work! Nicolas