[llvm] [VPlan] Introduce child regions as VPlan transform. (PR #129402)

[Florian Hahn via llvm-commits]

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@@ -376,23 +311,21 @@ void PlainCFGBuilder::buildPlainCFG(
   for (BasicBlock *BB : RPO) {
     // Create or retrieve the VPBasicBlock for this BB.
     VPBasicBlock *VPBB = getOrCreateVPBB(BB);
-    VPRegionBlock *Region = VPBB->getParent();
     Loop *LoopForBB = LI->getLoopFor(BB);
     // Set VPBB predecessors in the same order as they are in the incoming BB.
     if (!isHeaderBB(BB, LoopForBB)) {
       setVPBBPredsFromBB(VPBB, BB);
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fhahn wrote:

I just pushed an update to not rely on the predecessor order (see cc818012a9683fd4d1fe4dceb3a5e2fb32d91a44 for this change in isolation)

https://github.com/llvm/llvm-project/pull/129402