[clang] [llvm] security check cookie execute only when needed (PR #95904)

[Eli Friedman via cfe-commits]

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@@ -5,9 +5,20 @@ declare void @h(ptr, i64, ptr)
 
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efriedma-quic wrote:

Can we use update_llc_test_checks.py for this test?

https://github.com/llvm/llvm-project/pull/95904