[llvm] [TBAA] Recover !tbaa for a memcpy of struct with same type fields (PR #214116)

[Abhay Kanhere via llvm-commits]

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AbhayKanhere wrote:

Here I am checking TBAA is well-formed structurally before I retain it for current node.  This is to fix the scenario identified by crash / archer. I did try putting a helper in Verifier which can be reused here -- but ultimately on review feedback kept it here.

https://github.com/llvm/llvm-project/pull/214116