[llvm] [LoopInterchange] Constrain LI within supported loop nest depth (PR #118656)

[Michael Kruse via llvm-commits]

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@@ -0,0 +1,95 @@
+; REQUIRES: asserts
+; RUN: opt < %s -passes=loop-interchange -debug -disable-output 2>&1| FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+; For deep loop nest, delinearization should not be run.
+
+; CHECK-NOT: Delinearizing
+; CHECK-NOT: Strides:
+; CHECK-NOT: Terms:
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Meinersbur wrote:

`-NOT` checks are fragile. For instance, it will not match any of those after the "Unsupported depth of ..." line. If there is not such line, then this test will already fail because of that.

Consider adding additional `dbg() << ...` output somewhere with the reason that it has been skipped.

https://github.com/llvm/llvm-project/pull/118656