`const fn` specialization

I've been re-reading Tracking Issue for const_eval_select · Issue #124625 · rust-lang/rust · GitHub today because I wanted to make a function that currently uses intrinsics const fn. There is Tracking Issue for constifying x86 intrinsics in stdarch · Issue #149298 · rust-lang/rust · GitHub for x86-64, but nothing like for aarch64 or RISC-V. Since specialization exists on nightly in some form, I'm wondering if a similar mechanism could be used for this purpose. Essentially, having two functions...