Match either of cmp/xor in mask_reduce_all

Author: jhorstmann

tests/assembly/simd-intrinsic-mask-reduce.rs

@@ -32,7 +32,8 @@ extern "rust-intrinsic" {
 pub unsafe extern "C" fn mask_reduce_all(m: mask8x16) -> bool {
     // x86: psllw xmm0, 7
     // x86-NEXT: pmovmskb eax, xmm0
-    // cmp/xor followed by sete, depending on llvm version
+    // x86-NEXT: {{cmp ax, -1|xor eax, 65535}}
+    // x86-NEXT: sete al
     //
     // aarch64: shl v0.16b, v0.16b, #7
     // aarch64-NEXT: cmlt v0.16b, v0.16b, #0