[llvm] [BranchFolding] Fix assertion failure in HoistCommonCodeInSuccs (PR #141028)

[Jeremy Morse via llvm-commits]

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@@ -0,0 +1,80 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=armv7-apple-ios --run-pass=branch-folder %s -o - | FileCheck %s
+
+## Don't crash in branch-folder's HoistCommonCodeInSuccs when TBB and FBB are
+## the same block.
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jmorse wrote:

I think this comment needs to be detached from the implementation details and made broader -- "We hoist code from successor blocks, and in abnormal circumstances we can have control flow that branches to the same block -- test that we handle this correctly". Or something.

https://github.com/llvm/llvm-project/pull/141028