[llvm] [VPlan] Remove original loop if dead after vectorization. (PR #155497)

[Florian Hahn via llvm-commits]

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@@ -609,6 +611,66 @@ exit:
 }
 
 define void @low_trip_count_fold_tail_scalarized_store(ptr %dst) {
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fhahn wrote:

Just the common check below

https://github.com/llvm/llvm-project/pull/155497