`#[inline]` functions now that we no longer have any generics

[billythedummy]

https://matklad.github.io/2021/07/09/inline-in-rust.html:

That’s where the main usage of #[inline] comes from — it enables cross-crate inlining. Without #[inline], even the most trivial of functions can’t be inlined across the crate boundary. The benefit is not without a cost — the compiler implements this by compiling a separate copy of the #[inline] function with every crate it is used in, significantly increasing compile times.