[llvm] [VPlan] Manage created blocks directly in VPlan. (NFC) (PR #120918)

[Florian Hahn via llvm-commits]

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@@ -297,8 +297,6 @@ static bool mergeReplicateRegionsIntoSuccessors(VPlan &Plan) {
     DeletedRegions.insert(Region1);
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fhahn wrote:

Left as is for now, as we still need to track regions that have been transformed. Renamed to clarify, thanks

https://github.com/llvm/llvm-project/pull/120918