Test and reject out-of-bounds shuffle vectors

src/test/ui/simd/shuffle-not-out-of-bounds.rs

@@ -0,0 +1,23 @@
+// build-fail
+#![allow(non_camel_case_types)]
+#![feature(repr_simd, platform_intrinsics)]
+
+// Test for #73542 to verify out-of-bounds shuffle vectors do not compile.
+
+#[repr(simd)]
+#[derive(Copy, Clone)]
+struct f32x4(f32, f32, f32, f32);
+
+extern "platform-intrinsic" {
+    pub fn simd_shuffle4<T, U>(x: T, y: T, idx: [u32; 4]) -> U;
+}
+
+
+fn main() {
+    unsafe {
+        let vec1 = f32x4(1.0, 2.0, 3.0, 4.0);
+        let vec2 = f32x4(10_000.0, 20_000.0, 30_000.0, 40_000.0);
+        let shuffled: f32x4 = simd_shuffle4(vec1, vec2, [0, 4, 7, 9]);
+        //~^ ERROR: invalid monomorphization of `simd_shuffle4` intrinsic: shuffle index #3 is out
+    }
+}

src/test/ui/simd/shuffle-not-out-of-bounds.stderr

@@ -0,0 +1,9 @@
+error[E0511]: invalid monomorphization of `simd_shuffle4` intrinsic: shuffle index #3 is out of bounds (limit 8)
+  --> $DIR/shuffle-not-out-of-bounds.rs:20:31
+   |
+LL |         let shuffled: f32x4 = simd_shuffle4(vec1, vec2, [0, 4, 7, 9]);
+   |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0511`.