Rollup merge of rust-lang#93745 - tarcieri:stabilize-adx, r=cjgillot

Stabilize ADX target feature

This is a continuation of rust-lang#60109, which noted that while the ADX intrinsics were stabilized, the corresponding target feature never was.

This PR follows the same general structure and stabilizes the ADX target feature.

See also rust-lang#44839 - tracking issue for target feature

Author: Dylan-DPC

compiler/rustc_codegen_ssa/src/target_features.rs

@@ -148,7 +148,7 @@ const AARCH64_TIED_FEATURES: &[&[&str]] = &[
 ];
 
 const X86_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
-    ("adx", Some(sym::adx_target_feature)),
+    ("adx", None),
     ("aes", None),
     ("avx", None),
     ("avx2", None),

compiler/rustc_feature/src/accepted.rs

@@ -51,6 +51,8 @@ declare_features! (
     /// Allows the sysV64 ABI to be specified on all platforms
     /// instead of just the platforms on which it is the C ABI.
     (accepted, abi_sysv64, "1.24.0", Some(36167), None),
+    /// Allows using ADX intrinsics from `core::arch::{x86, x86_64}`.
+    (accepted, adx_target_feature, "1.61.0", Some(44839), None),
     /// Allows the definition of associated constants in `trait` or `impl` blocks.
     (accepted, associated_consts, "1.20.0", Some(29646), None),
     /// Allows using associated `type`s in `trait`s.

compiler/rustc_typeck/src/collect.rs

@@ -2689,7 +2689,6 @@ fn from_target_feature(
                 Some(sym::tbm_target_feature) => rust_features.tbm_target_feature,
                 Some(sym::wasm_target_feature) => rust_features.wasm_target_feature,
                 Some(sym::cmpxchg16b_target_feature) => rust_features.cmpxchg16b_target_feature,
-                Some(sym::adx_target_feature) => rust_features.adx_target_feature,
                 Some(sym::movbe_target_feature) => rust_features.movbe_target_feature,
                 Some(sym::rtm_target_feature) => rust_features.rtm_target_feature,
                 Some(sym::f16c_target_feature) => rust_features.f16c_target_feature,

library/core/src/lib.rs

@@ -207,7 +207,6 @@
 //
 // Target features:
 #![cfg_attr(bootstrap, feature(aarch64_target_feature))]
-#![feature(adx_target_feature)]
 #![feature(arm_target_feature)]
 #![feature(avx512_target_feature)]
 #![feature(cmpxchg16b_target_feature)]
@@ -219,6 +218,7 @@
 #![feature(sse4a_target_feature)]
 #![feature(tbm_target_feature)]
 #![feature(wasm_target_feature)]
+#![cfg_attr(bootstrap, feature(adx_target_feature))]
 
 // allow using `core::` in intra-doc links
 #[allow(unused_extern_crates)]