vget_low_s8 behind feature flag on beta

[dragostis]

While using the aarch64 intrinsics that are stable on beta I've noticed that vget_low_s8 still complains about not being given the stdsimd feature.

use std::arch::aarch64::*;

fn main() {
    [
        unsafe { vmovl_s8(vget_low_s8(val.0)) },
        unsafe { vmovl_s8(vget_high_s8(val.0)) },
    ];
}

Meta

rustc --version --verbose:

rustc 1.59.0-beta.8 (1945ce657 2022-02-12)
binary: rustc
commit-hash: 1945ce6579506787e0b18f0a2ea03fdb4dfc81c7
commit-date: 2022-02-12
host: x86_64-apple-darwin
release: 1.59.0-beta.8
LLVM version: 13.0.0

Backtrace

error[E0658]: use of unstable library feature 'stdsimd'

[dragostis]

cc #91951

[Mark-Simulacrum]

cc @Amanieu

It looks like this may have gotten overlooked during stabilization? It likely does not block a release, though, and I'm not inclined to do fairly last minute backports of some subset of intrinsics

[dragostis]

Most likely overlooked since its cognate, vget_high_s8, was stabilized.

[Amanieu]

Yes, it seems this was overlooked in the stabilization. It's an easy fix, but probably not worth backporting at the last minute. In the meantime it should be possible to work around using some of the other intrinsics.

[jieyouxu]

Triage: stabilization fixed in stdarch submodule bump inside #94529.