[llvm] [LoopFlatten] Invalidate SCEV on each widening (PR #211819)

[Ryotaro Kasuga via llvm-commits]

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@@ -0,0 +1,94 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -passes='loop(loop-flatten),print<scalar-evolution>' -disable-output 2>&1 | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
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kasuga-fj wrote:

```suggestion
```

Probably unnecessary.

https://github.com/llvm/llvm-project/pull/211819