[llvm] [Attributor][FIX] Mark "may" accesses through call sites as such (PR #107439)

[Johannes Doerfert via llvm-commits]

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@@ -192,6 +192,7 @@ define i32 @test_ncheck2(i32 %0) #0 {
 
 attributes #0 = { noinline nounwind sspstrong uwtable}
 
+;.
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jdoerfert wrote:

It's in a standalone commit. I can push it first. Look at commit #3 only.

https://github.com/llvm/llvm-project/pull/107439