[llvm] [LoopUnroll] Remove redundant debug instructions after blocks have been merged (PR #91246)

[Arthur Eubanks via llvm-commits]

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@@ -0,0 +1,45 @@
+; RUN: opt < %s -S -passes=loop-unroll | FileCheck %s
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aeubanks wrote:

this isn't properly using update_test_checks.py, see the comments in that file. I believe the CHECK lines below need to be removed first. as the comments in update_test_checks.py say, please verify that there is a difference in IR with and without the loop unroll cleanup change

https://github.com/llvm/llvm-project/pull/91246