[llvm] [LoopVectorize] Check for vector-to-scalar casts in legalizer (PR #106244)

[Ramkumar Ramachandra via llvm-commits]

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@@ -0,0 +1,32 @@
+; RUN: opt --force-widen-divrem-via-safe-divisor=false -passes=loop-vectorize -S --debug-only=loop-vectorize < %s 2>&1 | FileCheck %s
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artagnon wrote:

> I was able to reproduce it without this flag on some targets, but it seemed more robust to just force the code path that triggers the assert rather than depend on the target specific heuristics which I assume could be changed at any time.

Sounds good. +1 for making it target-independent.

https://github.com/llvm/llvm-project/pull/106244