[llvm] [LoopInterchange] Add test for IR modification stops partway (PR #205562)

[Ryotaro Kasuga via llvm-commits]

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@@ -0,0 +1,88 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -passes=loop-interchange -loop-interchange-profitabilities=ignore -debug-only=loop-interchange -S 2>&1 | FileCheck %s
+; REQUIRES: asserts
+
+; This test shows a case where the IR‑transformation phase of loop interchange
+; can fail partway. As a result, the final output becomes a partially
+; transformed IR. The IR‑transformation phase must not stop partway; in such
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kasuga-fj wrote:

Added, thanks

https://github.com/llvm/llvm-project/pull/205562