Auto merge of rust-lang#123167 - DianQK:test-simd-wide-sum, r=scottmcm

Restore the test checks for `wider_reduce_into_iter`

The current minimum support is for LLVM 17. Context: rust-lang#116018 (comment).

r? scottmcm

tests/codegen/simd/simd-wide-sum.rs

@@ -51,8 +51,8 @@ pub fn wider_reduce_iter(x: Simd<u8, N>) -> u16 {
 #[no_mangle]
 // CHECK-LABEL: @wider_reduce_into_iter
 pub fn wider_reduce_into_iter(x: Simd<u8, N>) -> u16 {
-    // FIXME: It would be nice if this was exactly the same as the above tests,
-    // but at the time of writing this comment, that didn't happen on LLVM main.
-    // CHECK: call i16 @llvm.vector.reduce.add
+    // CHECK: zext <16 x i8>
+    // CHECK-SAME: to <16 x i16>
+    // CHECK: call i16 @llvm.vector.reduce.add.v16i16(<16 x i16>
     x.to_array().into_iter().map(u16::from).sum()
 }