[llvm] LoopVectorize: guard appending InstsToScalarize; fix bug (PR #88720)

[Ramkumar Ramachandra via llvm-commits]

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@@ -5821,7 +5821,8 @@ void LoopVectorizationCostModel::collectInstsToScalarize(ElementCount VF) {
         // invalid scalarization costs.
         // Do not apply discount logic if hacked cost is needed
         // for emulated masked memrefs.
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artagnon wrote:

Sorry for the delay! See #91120.

https://github.com/llvm/llvm-project/pull/88720