[llvm] [LoopInterchange] Ignore the cost-model, force interchange if legal (PR #148858)

[Ryotaro Kasuga via llvm-commits]

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@@ -0,0 +1,50 @@
+; RUN: opt < %s -passes=loop-interchange -pass-remarks-output=%t -disable-output -loop-interchange-profitabilities=ignore -S
+; RUN: FileCheck --input-file=%t %s
+
+; There should be no reason to interchange this, unless it is forced.
+;
+;     for (int i = 0; i<N; i++)
+;       for (int j = 0; j<N; j++)
+;         A[i][j] = 42;
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kasuga-fj wrote:

```suggestion
;     for (int i = 0; i<1024; i++)
;       for (int j = 0; j<1024; j++)
;         A[i][j] = 42;
```

https://github.com/llvm/llvm-project/pull/148858