[llvm] [JumpThreading] Thread over BB with only an unconditional branch (PR #86312)

[Quentin Dian via llvm-commits]

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@@ -1,3 +1,4 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
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DianQK wrote:

Please submit this change separately.
I'm not sure if this test case is broken.

https://github.com/llvm/llvm-project/pull/86312