Refactoring a "simple" function in dmd source

[Alexandru Ermicioi]

On Sunday, 31 December 2023 at 13:02:27 UTC, Siarhei Siamashka 
wrote:
> The listed benefits are nice and very much welcome, but it's a 
> copy-paste job from Phobos into the DMD codebase. Raising a 
> question again about the reasons why DMD itself isn't using 
> Phobos like any normal applications do.

Chicken and egg problem, should've been discussed before here a 
lot.

> Also whenever game developers are complaining in this forum 
> about poor `@nogc` support, they are being told that the GC is 
> totally fine and they are just unreasonably biased against it. 
> All of this while the DMD compiler itself is doing fancy 
> hackish stunts with memory allocation. Games are latency 
> sensitive. Compilers are not.

Imho, this PR is nowhere imbued with @nogc fanciness here, just 
the property of D arrays that, now are properly taken advantage 
of, if you're talking about PR and not how compiler itself is 
working.