Enable xray support for Mac

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

@@ -22,6 +22,7 @@ pub(crate) fn target() -> Target {
             max_atomic_width: Some(128),
             // FIXME: The leak sanitizer currently fails the tests, see #88132.
             supported_sanitizers: SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::THREAD,
+            supports_xray: true,
             ..opts
         },
     }

compiler/rustc_target/src/spec/targets/x86_64_apple_darwin.rs

@@ -23,6 +23,7 @@ pub(crate) fn target() -> Target {
                 | SanitizerSet::CFI
                 | SanitizerSet::LEAK
                 | SanitizerSet::THREAD,
+            supports_xray: true,
             ..opts
         },
     }

tests/assembly/x86_64-xray.rs

@@ -0,0 +1,16 @@
+//@ assembly-output: emit-asm
+//@ compile-flags: --crate-type lib -Zinstrument-xray=always -C llvm-args=-x86-asm-syntax=intel --target x86_64-unknown-linux-gnu
+//@ needs-llvm-components: x86
+//@ only-x86_64
+//@ ignore-sgx
+
+// CHECK-LABEL: xray_func:
+#[no_mangle]
+pub fn xray_func() {
+    // CHECK: nop word ptr [rax + rax + 512]
+
+    std::hint::black_box(());
+
+    // CHECK: ret
+    // CHECK-NEXT: nop word ptr cs:[rax + rax + 512]
+}

tests/ui/instrument-xray/platform-support.rs

@@ -0,0 +1,27 @@
+//@ only-nightly (flag is still unstable)
+//@ needs-xray
+
+//@ revisions: unsupported
+//@[unsupported] needs-llvm-components: x86
+//@[unsupported] compile-flags: -Z instrument-xray --target=x86_64-pc-windows-msvc
+
+//@ revisions: x86_64-linux
+//@[x86_64-linux] needs-llvm-components: x86
+//@[x86_64-linux] compile-flags: -Z instrument-xray --target=x86_64-unknown-linux-gnu
+//@[x86_64-linux] check-pass
+
+//@ revisions: x86_64-darwin
+//@[x86_64-darwin] needs-llvm-components: x86
+//@[x86_64-darwin] compile-flags: -Z instrument-xray --target=x86_64-apple-darwin
+//@[x86_64-darwin] check-pass
+
+//@ revisions: aarch64-darwin
+//@[aarch64-darwin] needs-llvm-components: aarch64
+//@[aarch64-darwin] compile-flags: -Z instrument-xray --target=aarch64-apple-darwin
+//@[aarch64-darwin] check-pass
+
+#![feature(no_core)]
+#![no_core]
+#![no_main]
+
+//[unsupported]~? ERROR XRay instrumentation is not supported for this target