[llvm] [VPlan] Replace VPRegionBlock with explicit CFG before execute (NFCI). (PR #117506)

[via llvm-commits]

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@@ -437,14 +441,18 @@ void VPBasicBlock::connectToPredecessors(VPTransformState &State) {
   for (VPBlockBase *PredVPBlock : getHierarchicalPredecessors()) {
     VPBasicBlock *PredVPBB = PredVPBlock->getExitingBasicBlock();
     auto &PredVPSuccessors = PredVPBB->getHierarchicalSuccessors();
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ayalz wrote:

Note: getHierarchical*() are still needed due to replicate regions, when VF>1 (but removed when unrolling only, with UF>1, VF=1?)

https://github.com/llvm/llvm-project/pull/117506