Merge pull request #2050 from folkertdev/aarch64-rand

add ACLE random number generation intrinsics

Author: sayantn

crates/core_arch/src/aarch64/mod.rs

@@ -17,6 +17,10 @@ mod mte;
 #[unstable(feature = "stdarch_aarch64_mte", issue = "129010")]
 pub use self::mte::*;
 
+mod rand;
+#[unstable(feature = "stdarch_aarch64_rand", issue = "153514")]
+pub use self::rand::*;
+
 mod neon;
 #[stable(feature = "neon_intrinsics", since = "1.59.0")]
 pub use self::neon::*;

crates/core_arch/src/aarch64/mte.rs

@@ -3,35 +3,17 @@
 //! [ACLE documentation](https://arm-software.github.io/acle/main/acle.html#markdown-toc-mte-intrinsics)
 
 unsafe extern "unadjusted" {
-    #[cfg_attr(
-        any(target_arch = "aarch64", target_arch = "arm64ec"),
-        link_name = "llvm.aarch64.irg"
-    )]
+    #[link_name = "llvm.aarch64.irg"]
     fn irg_(ptr: *const (), exclude: i64) -> *const ();
-    #[cfg_attr(
-        any(target_arch = "aarch64", target_arch = "arm64ec"),
-        link_name = "llvm.aarch64.gmi"
-    )]
+    #[link_name = "llvm.aarch64.gmi"]
     fn gmi_(ptr: *const (), exclude: i64) -> i64;
-    #[cfg_attr(
-        any(target_arch = "aarch64", target_arch = "arm64ec"),
-        link_name = "llvm.aarch64.ldg"
-    )]
+    #[link_name = "llvm.aarch64.ldg"]
     fn ldg_(ptr: *const (), tag_ptr: *const ()) -> *const ();
-    #[cfg_attr(
-        any(target_arch = "aarch64", target_arch = "arm64ec"),
-        link_name = "llvm.aarch64.stg"
-    )]
+    #[link_name = "llvm.aarch64.stg"]
     fn stg_(tagged_ptr: *const (), addr_to_tag: *const ());
-    #[cfg_attr(
-        any(target_arch = "aarch64", target_arch = "arm64ec"),
-        link_name = "llvm.aarch64.addg"
-    )]
+    #[link_name = "llvm.aarch64.addg"]
     fn addg_(ptr: *const (), value: i64) -> *const ();
-    #[cfg_attr(
-        any(target_arch = "aarch64", target_arch = "arm64ec"),
-        link_name = "llvm.aarch64.subp"
-    )]
+    #[link_name = "llvm.aarch64.subp"]
     fn subp_(ptr_a: *const (), ptr_b: *const ()) -> i64;
 }
 
@@ -127,42 +109,46 @@ mod test {
     use super::*;
     use stdarch_test::assert_instr;
 
-    #[cfg_attr(all(test, not(target_env = "msvc")), assert_instr(irg))] // FIXME: MSVC  `dumpbin` doesn't support MTE
+    // Instruction tests are separate because the functions use generics.
+    //
+    // FIXME: As of 2026 MSVC  `dumpbin` doesn't support MTE.
+
+    #[cfg_attr(not(target_env = "msvc"), assert_instr(irg))]
     #[allow(dead_code)]
     #[target_feature(enable = "mte")]
     unsafe fn test_arm_mte_create_random_tag(src: *const (), mask: u64) -> *const () {
         __arm_mte_create_random_tag(src, mask)
     }
 
-    #[cfg_attr(all(test, not(target_env = "msvc")), assert_instr(addg))]
+    #[cfg_attr(not(target_env = "msvc"), assert_instr(addg))]
     #[allow(dead_code)]
     #[target_feature(enable = "mte")]
     unsafe fn test_arm_mte_increment_tag(src: *const ()) -> *const () {
         __arm_mte_increment_tag::<1, _>(src)
     }
 
-    #[cfg_attr(all(test, not(target_env = "msvc")), assert_instr(gmi))]
+    #[cfg_attr(not(target_env = "msvc"), assert_instr(gmi))]
     #[allow(dead_code)]
     #[target_feature(enable = "mte")]
     unsafe fn test_arm_mte_exclude_tag(src: *const (), excluded: u64) -> u64 {
         __arm_mte_exclude_tag(src, excluded)
     }
 
-    #[cfg_attr(all(test, not(target_env = "msvc")), assert_instr(stg))]
+    #[cfg_attr(not(target_env = "msvc"), assert_instr(stg))]
     #[allow(dead_code)]
     #[target_feature(enable = "mte")]
     unsafe fn test_arm_mte_set_tag(src: *const ()) {
         __arm_mte_set_tag(src)
     }
 
-    #[cfg_attr(all(test, not(target_env = "msvc")), assert_instr(ldg))]
+    #[cfg_attr(not(target_env = "msvc"), assert_instr(ldg))]
     #[allow(dead_code)]
     #[target_feature(enable = "mte")]
     unsafe fn test_arm_mte_get_tag(src: *const ()) -> *const () {
         __arm_mte_get_tag(src)
     }
 
-    #[cfg_attr(all(test, not(target_env = "msvc")), assert_instr(subp))]
+    #[cfg_attr(not(target_env = "msvc"), assert_instr(subp))]
     #[allow(dead_code)]
     #[target_feature(enable = "mte")]
     unsafe fn test_arm_mte_ptrdiff(a: *const (), b: *const ()) -> i64 {

crates/core_arch/src/aarch64/rand.rs

@@ -0,0 +1,48 @@
+//! AArch64 Random Number intrinsics
+//!
+//! [ACLE documentation](https://arm-software.github.io/acle/main/acle.html#random-number-generation-intrinsics)
+
+#[cfg(test)]
+use stdarch_test::assert_instr;
+
+unsafe extern "unadjusted" {
+    #[link_name = "llvm.aarch64.rndr"]
+    fn rndr_() -> Tuple;
+
+    #[link_name = "llvm.aarch64.rndrrs"]
+    fn rndrrs_() -> Tuple;
+}
+
+#[repr(C)]
+struct Tuple {
+    bits: u64,
+    status: bool,
+}
+
+/// Stores a 64-bit random number into the object pointed to by the argument and returns
+/// zero. If the implementation could not generate a random number within a reasonable
+/// period of time the object pointed to by the input is set to zero and a non-zero value
+/// is returned.
+#[inline]
+#[target_feature(enable = "rand")]
+#[cfg_attr(test, assert_instr(mrs))]
+#[unstable(feature = "stdarch_aarch64_rand", issue = "153514")]
+pub unsafe fn __rndr(value: *mut u64) -> i32 {
+    let Tuple { bits, status } = rndr_();
+    unsafe { *value = bits };
+    status as i32
+}
+
+/// Reseeds the random number generator. After that stores a 64-bit random number into
+/// the object pointed to by the argument and returns zero. If the implementation could
+/// not generate a random number within a reasonable period of time the object pointed
+/// to by the input is set to zero and a non-zero value is returned.
+#[inline]
+#[target_feature(enable = "rand")]
+#[cfg_attr(test, assert_instr(mrs))]
+#[unstable(feature = "stdarch_aarch64_rand", issue = "153514")]
+pub unsafe fn __rndrrs(value: *mut u64) -> i32 {
+    let Tuple { bits, status } = rndrrs_();
+    unsafe { *value = bits };
+    status as i32
+}

crates/stdarch-verify/tests/arm.rs

@@ -445,6 +445,7 @@ fn verify_all_signatures() {
                     && !rust.file.ends_with("v7.rs\"")
                     && !rust.file.ends_with("v8.rs\"")
                     && !rust.file.ends_with("mte.rs\"")
+                    && !rust.file.ends_with("rand.rs\"")
                     && !rust.file.ends_with("ex.rs\"")
                     && !skip_intrinsic_verify.contains(&rust.name)
                 {