diff --git a/tests/assembly/aarch64-simd-mask-reduce.rs b/tests/assembly/aarch64-simd-mask-reduce.rs
new file mode 100644
index 0000000000000..cce2c3042921b
--- /dev/null
+++ b/tests/assembly/aarch64-simd-mask-reduce.rs
@@ -0,0 +1,33 @@
+// verify that simd mask reductions do not introduce additional bit shift operations
+
+// assembly-output: emit-asm
+// compile-flags: --crate-type=lib -O --target aarch64-unknown-linux-gnu
+// needs-llvm-components: aarch64
+// only-aarch64
+// only-linux
+
+#![feature(repr_simd, platform_intrinsics)]
+#![allow(non_camel_case_types)]
+
+#[repr(simd)]
+#[derive(Copy, Clone)]
+pub struct mask8x16([i8; 16]);
+
+extern "platform-intrinsic" {
+    fn simd_reduce_all<T>(x: T) -> bool;
+    fn simd_reduce_any<T>(x: T) -> bool;
+}
+
+// CHECK-LABEL: mask_reduce_all:
+#[no_mangle]
+pub unsafe fn mask_reduce_all(m: mask8x16) -> bool {
+    // CHECK: umaxv
+    simd_reduce_all(m)
+}
+
+// CHECK-LABEL: mask_reduce_any:
+#[no_mangle]
+pub unsafe fn mask_reduce_any(m: mask8x16) -> bool {
+    // CHECK: umaxv
+    simd_reduce_any(m)
+}
diff --git a/tests/assembly/x86_64-simd-mask-reduce.rs b/tests/assembly/x86_64-simd-mask-reduce.rs
new file mode 100644
index 0000000000000..354d0d353bb73
--- /dev/null
+++ b/tests/assembly/x86_64-simd-mask-reduce.rs
@@ -0,0 +1,33 @@
+// verify that simd mask reductions do not introduce additional bit shift operations
+
+// assembly-output: emit-asm
+// compile-flags: --crate-type=lib -O -C llvm-args=-x86-asm-syntax=intel
+// only-x86_64
+
+#![feature(repr_simd, platform_intrinsics)]
+#![allow(non_camel_case_types)]
+
+#[repr(simd)]
+#[derive(Copy, Clone)]
+pub struct mask8x16([i8; 16]);
+
+extern "platform-intrinsic" {
+    fn simd_reduce_all<T>(x: T) -> bool;
+    fn simd_reduce_any<T>(x: T) -> bool;
+}
+
+// CHECK-LABEL: mask_reduce_all:
+#[no_mangle]
+pub unsafe fn mask_reduce_all(m: mask8x16) -> bool {
+    // CHECK-NOT: psllw
+    // CHECK: pmovmskb
+    simd_reduce_all(m)
+}
+
+// CHECK-LABEL: mask_reduce_any:
+#[no_mangle]
+pub unsafe fn mask_reduce_any(m: mask8x16) -> bool {
+    // CHECK-NOT: psllw
+    // CHECK: pmovmskb
+    simd_reduce_any(m)
+}