This is a tracking issue for RFC 2325, adding SIMD support to stable Rust. There's a number of components here, including:

• #[target_feature(enable = ...)]
• Names of accepted target features - currently proposed
• #[cfg(target_feature = ...)]
• is_target_feature_detected! macro
• std::arch naming and submodules

The initial implementation of this is being added in #48513 and the next steps would be:

• Adjust documentation (see instructions on forge)
• Stabilization PR (see instructions on forge)

Known issues

• is_target_feature_detected! takes different arguments that #[target_feature]