[llvm] [AMDGPU][Attributor] Check the validity of a dependent AA before using its value (PR #114165)

[Shilei Tian via llvm-commits]

shiltian wrote:

* **#114165** <a href="https://app.graphite.dev/github/pr/llvm/llvm-project/114165?utm_source=stack-comment-icon" target="_blank"><img src="https://static.graphite.dev/graphite-32x32-black.png" alt="Graphite" width="10px" height="10px"/></a> 👈
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https://github.com/llvm/llvm-project/pull/114165