[llvm] [Attributor][FIX] Ensure nonnull IR deduction is not optimistic (PR #93322)

[via llvm-commits]

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@@ -1609,6 +1612,33 @@ define void @multi_ret_caller(ptr %p) {
   ret void
 }
 
+; From https://github.com/llvm/llvm-project/pull/85810
+ at G = internal global i64 1, align 8
+define dso_local ptr @update_global_in_alive_bb() {
+; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn
+; CHECK-LABEL: define {{[^@]+}}@update_global_in_alive_bb
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lcvon007 wrote:

I think this MR has solved the problem I find,  but this testcase actually is not meaningful for this PR, because it will pass even if nonnull attribute is added by mistake again. what's your opinion about this? @jdoerfert 

https://github.com/llvm/llvm-project/pull/93322