Hi Nikita, I performed a few other benchmarks in order to provide a little bit more insights into the performance aspect of the RFC. My latest measurement is using the same setup as the previous one, although I made a few smaller changes in the process (e.g. changing the order of the tests). So at the end, I got the following results:
- Laravel demo app: +0.1% - Symfony demo app: +0.43% - bench.php: +0.4% - custom concat bench: +3.89% The results are comparing the "literals" branch with the commit in master on which Joe's work is based. As far as I remember, the simpler variant of is_literals had a 0.1% slowdown in case of Symfony, and 2.09% in case of the custom concat benchmark. Personally, I think even the current numbers are acceptable, especially because PHP 8.1 is going to be roughly 30% faster than PHP 8.0 according to my benchmark in case of the Symfony demo app. Laravel's result is very similar, but I don't remember about the exact numbers. Regards: Máté