Enable outline-atomics by default on aarch64 Apple targets

compiler/rustc_target/src/spec/targets/aarch64_apple_darwin.rs

@@ -19,6 +19,7 @@ pub(crate) fn target() -> Target {
             mcount: "\u{1}mcount".into(),
             cpu: "apple-m1".into(),
             max_atomic_width: Some(128),
+            features: "+outline-atomics,-lse".into(),
             // FIXME: The leak sanitizer currently fails the tests, see #88132.
             supported_sanitizers: SanitizerSet::ADDRESS
                 | SanitizerSet::CFI

compiler/rustc_target/src/spec/targets/aarch64_apple_ios.rs

@@ -16,7 +16,7 @@ pub(crate) fn target() -> Target {
             .into(),
         arch,
         options: TargetOptions {
-            features: "+neon,+apple-a7".into(),
+            features: "+neon,+apple-a7,+outline-atomics".into(),
             max_atomic_width: Some(128),
             supported_sanitizers: SanitizerSet::ADDRESS
                 | SanitizerSet::THREAD

compiler/rustc_target/src/spec/targets/aarch64_apple_tvos.rs

@@ -16,7 +16,7 @@ pub(crate) fn target() -> Target {
             .into(),
         arch,
         options: TargetOptions {
-            features: "+neon,+apple-a7".into(),
+            features: "+neon,+apple-a7,+outline-atomics".into(),
             max_atomic_width: Some(128),
             ..opts
         },

compiler/rustc_target/src/spec/targets/aarch64_apple_visionos.rs

@@ -16,7 +16,7 @@ pub(crate) fn target() -> Target {
             .into(),
         arch,
         options: TargetOptions {
-            features: "+neon,+apple-a16".into(),
+            features: "+neon,+apple-a16,+outline-atomics".into(),
             max_atomic_width: Some(128),
             supported_sanitizers: SanitizerSet::ADDRESS | SanitizerSet::THREAD,
             ..opts

compiler/rustc_target/src/spec/targets/aarch64_apple_watchos.rs

@@ -16,7 +16,7 @@ pub(crate) fn target() -> Target {
             .into(),
         arch,
         options: TargetOptions {
-            features: "+v8a,+neon,+apple-a7".into(),
+            features: "+v8a,+neon,+apple-a7,+outline-atomics".into(),
             max_atomic_width: Some(128),
             dynamic_linking: false,
             position_independent_executables: true,

library/compiler-builtins/builtins-test/tests/lse.rs

@@ -1,6 +1,6 @@
 #![feature(decl_macro)] // so we can use pub(super)
 #![feature(macro_metavar_expr_concat)]
-#![cfg(all(target_arch = "aarch64", target_os = "linux"))]
+#![cfg(all(target_arch = "aarch64"))]
 
 /// Translate a byte size to a Rust type.
 macro int_ty {

library/compiler-builtins/compiler-builtins/src/aarch64_outline_atomics.rs

@@ -135,18 +135,44 @@ macro_rules! stxp {
     };
 }
 
+// Apple and Elf have different symbol access syntax
+#[cfg(not(target_vendor = "apple"))]
+macro_rules! sym {
+    ($sym:literal) => {
+        $sym
+    };
+}
+#[cfg(target_vendor = "apple")]
+macro_rules! sym {
+    ($sym:literal) => {
+        concat!($sym, "@PAGE")
+    };
+}
+#[cfg(not(target_vendor = "apple"))]
+macro_rules! sym_off {
+    ($sym:literal) => {
+        concat!(":lo12:", $sym)
+    };
+}
+#[cfg(target_vendor = "apple")]
+macro_rules! sym_off {
+    ($sym:literal) => {
+        concat!($sym, "@PAGEOFF")
+    };
+}
+
 // If supported, perform the requested LSE op and return, or fallthrough.
 macro_rules! try_lse_op {
     ($op: literal, $ordering:ident, $bytes:tt, $($reg:literal,)* [ $mem:ident ] ) => {
         concat!(
-            ".arch_extension lse; ",
-            "adrp    x16, {have_lse}; ",
-            "ldrb    w16, [x16, :lo12:{have_lse}]; ",
-            "cbz     w16, 8f; ",
+            ".arch_extension lse\n",
+            concat!("adrp    x16, ", sym!("{have_lse}"), "\n"),
+            concat!("ldrb    w16, [x16, ", sym_off!("{have_lse}"), "]\n"),
+            "cbz     w16, 8f\n",
             // LSE_OP  s(reg),* [$mem]
-            concat!(lse!($op, $ordering, $bytes), $( " ", reg!($bytes, $reg), ", " ,)* "[", stringify!($mem), "]; ",),
-            "ret; ",
-            "8:"
+            concat!(lse!($op, $ordering, $bytes), $( " ", reg!($bytes, $reg), ", " ,)* "[", stringify!($mem), "]\n",),
+            "ret
+            8:"
         )
     };
 }