diff --git a/tests/assembly-llvm/slice-is-ascii.rs b/tests/assembly-llvm/slice-is-ascii.rs
index 3b782ab2cd82..00deb23e9a6c 100644
--- a/tests/assembly-llvm/slice-is-ascii.rs
+++ b/tests/assembly-llvm/slice-is-ascii.rs
@@ -1,32 +1,12 @@
-//@ revisions: X86_64 LA64
+//@ revisions: LA64
 //@ assembly-output: emit-asm
 //@ compile-flags: -C opt-level=3
 //
-//@ [X86_64] only-x86_64
-//@ [X86_64] compile-flags: -C target-cpu=znver4
-//@ [X86_64] compile-flags: -C llvm-args=-x86-asm-syntax=intel
-//
 //@ [LA64] only-loongarch64
 
 #![crate_type = "lib"]
 
-/// Verify `is_ascii` generates efficient code on different architectures:
-///
-/// - x86_64: Must NOT use `kshiftrd`/`kshiftrq` (broken AVX-512 auto-vectorization).
-///   The fix uses explicit SSE2 intrinsics (`pmovmskb`/`vpmovmskb`).
-///   See: https://github.com/llvm/llvm-project/issues/176906
-///
 /// - loongarch64: Should use `vmskltz.b` instruction for the fast-path.
-///   This architecture still relies on LLVM auto-vectorization.
-
-// X86_64-LABEL: test_is_ascii
-// X86_64-NOT: kshiftrd
-// X86_64-NOT: kshiftrq
-// Verify explicit SSE2/AVX intrinsics are used:
-// - pmovmskb/vpmovmskb: efficient mask extraction from the MSBs
-// - vpor/por: OR-combining of 4x 16-byte loads (2x unrolled, 64-byte chunks)
-// X86_64: {{vpmovmskb|pmovmskb}}
-// X86_64: {{vpor|por}}
 
 // LA64-LABEL: test_is_ascii
 // LA64: vmskltz.b