[llvm] [VPlan] Hook IR blocks into VPlan during skeleton creation (NFC) (PR #114292)

[via llvm-commits]

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@@ -8038,6 +8051,20 @@ EpilogueVectorizerEpilogueLoop::emitMinimumVectorEpilogueIterCountCheck(
   }
   ReplaceInstWithInst(Insert->getTerminator(), &BI);
   LoopBypassBlocks.push_back(Insert);
+
+  // A new entry block has been created for the epilogue VPlan. Hook it in.
+  VPIRBasicBlock *NewEntry = VPIRBasicBlock::fromBasicBlock(Insert);
+  VPBasicBlock *OldEntry = Plan.getEntry();
+  VPBlockUtils::reassociateBlocks(OldEntry, NewEntry);
+  Plan.setEntry(NewEntry);
+  for (auto &R : make_early_inc_range(*NewEntry)) {
+    auto *VPIR = dyn_cast<VPIRInstruction>(&R);
+    if (!VPIR || !isa<PHINode>(VPIR->getInstruction()))
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ayalz wrote:

Surely VPIR isn't null, having just created NewEntry fromBasicBlock Insert.

https://github.com/llvm/llvm-project/pull/114292