[llvm] [MemCpyOpt] Fix the invalid code modification for GEP (PR #68479)

[Yingwei Zheng via llvm-commits]

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@@ -0,0 +1,51 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
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dtcxzyw wrote:

I cannot reproduce the crash `LLVM ERROR: Function @test_gep_modified changed by MemCpyOptPass without invalidating analyses` on the trunk build.


https://github.com/llvm/llvm-project/pull/68479