Typed property assign should be optimized more

Description

Classes are very often used as a simple data holding structure which is created and destroyed millions times per script lifecycle/run.

In https://3v4l.org/CMktE/rfc#vgit.master I have discovered a "class like struct" is slower than an array. This is something not fully surprising on the first sight.

However, https://3v4l.org/hSSFJ/rfc#vgit.master, same demo with propoted properties only, with empty constructor, is not (much if any) faster.

Initially I thought the interpreted code in the constructor will contribute the most to the total run time. This seems to be not true, it seems the most of the time is spent in object allocation and release. If an object has no cycles, it should be fast. I hope there is a room to optimize the object allocation/release more and make this core part of php faster.

let's focus on typed property assign performance solely here

repro: https://3v4l.org/FGeEf

从 3v4l.org/FGeEf 的复现开始，并针对当前 PHP 解释器对类型化属性赋值案例进行性能分析。在提出优化方案之前，确定哪个分配或赋值路径占主导；完成的标准是在不改变语义的情况下取得经过测量的改进，并在项目提供此类检查时由有针对性的回归或性能检查提供支持。