[flang] [llvm] Reland [VPlan] Expand WidenInt inductions with nuw/nsw (PR #168354)

[Ramkumar Ramachandra via llvm-commits]

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@@ -0,0 +1,64 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 6
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artagnon wrote:

The crash is a very particular case of two identical muls being produced, one by expanding WidenIntOrFp, and the other one by expanding PtrInduction: the identical muls are necessary for cse to crash. I'm not able to replicate the crash in any other way.

https://github.com/llvm/llvm-project/pull/168354