Rollup merge of rust-lang#137491 - jieyouxu:mango-less-likely, r=saethlin

Tighten `str-to-string-128690.rs``CHECK{,-NOT}`s to make it less likely to incorrectly fail with symbol name mangling

The `invoke` to match on to `CHECK` or `CHECK-NOT` (latest master) looks like

```llvm
  %_0.i.i.i.i.i.i.i.i.i.i.i.i.i1.i = invoke noundef zeroext i1 ``@"_ZN42_$LT$str$u20$as$u20$core..fmt..Display$GT$3fmt17ha18033e7fb4f14fcE"(ptr`` noalias noundef nonnull readonly align 1 %_3.val.i.i.i.i.i.i.i.i.i.i.i.i.i, i64 noundef %_3.val1.i.i.i.i.i.i.i.i.i.i.i.i.i, ptr noalias noundef nonnull align 8 dereferenceable(64) %formatter.i)
          to label %bb1.i unwind label %cleanup.i, !noalias !80
```

in the local `.ll` output.

This test incorrectly failed in rust-lang#137483 (comment) due to

```
// CHECK-NOT: {{(call|invoke).*}}fmt
```

matching against the unrelated call

```llvm
tail call void ``@_RNvNtCseLfmtnDCoTB_5alloc7raw_vec12handle_error``
```

It's not pretty by any means, but...

r? ``@saethlin``

Author: jhpratt

tests/codegen/issues/str-to-string-128690.rs

@@ -2,25 +2,27 @@
 #![crate_type = "lib"]
 
 //! Make sure str::to_string is specialized not to use fmt machinery.
+//!
+//! Note that the `CHECK-NOT`s here try to match on calls to functions under `core::fmt`.
 
 // CHECK-LABEL: define {{(dso_local )?}}void @one_ref
 #[no_mangle]
 pub fn one_ref(input: &str) -> String {
-    // CHECK-NOT: {{(call|invoke).*}}fmt
+    // CHECK-NOT: {{(call|invoke)}}{{.*}}@{{.*}}core{{.*}}fmt{{.*}}
     input.to_string()
 }
 
 // CHECK-LABEL: define {{(dso_local )?}}void @two_ref
 #[no_mangle]
 pub fn two_ref(input: &&str) -> String {
-    // CHECK-NOT: {{(call|invoke).*}}fmt
+    // CHECK-NOT: {{(call|invoke)}}{{.*}}@{{.*}}core{{.*}}fmt{{.*}}
     input.to_string()
 }
 
 // CHECK-LABEL: define {{(dso_local )?}}void @thirteen_ref
 #[no_mangle]
 pub fn thirteen_ref(input: &&&&&&&&&&&&&str) -> String {
-    // CHECK-NOT: {{(call|invoke).*}}fmt
+    // CHECK-NOT: {{(call|invoke)}}{{.*}}@{{.*}}core{{.*}}fmt{{.*}}
     input.to_string()
 }
 
@@ -31,6 +33,6 @@ pub fn thirteen_ref(input: &&&&&&&&&&&&&str) -> String {
 // CHECK-LABEL: define {{(dso_local )?}}void @fourteen_ref
 #[no_mangle]
 pub fn fourteen_ref(input: &&&&&&&&&&&&&&str) -> String {
-    // CHECK: {{(call|invoke).*}}fmt
+    // CHECK: {{(call|invoke)}}{{.*}}@{{.*}}core{{.*}}fmt{{.*}}
     input.to_string()
 }