[llvm] [VPlan] Model branch cond to enter scalar epilogue in VPlan. (PR #92651)

[via llvm-commits]

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@@ -815,6 +819,42 @@ VPlanPtr VPlan::createInitialVPlan(const SCEV *TripCount, ScalarEvolution &SE,
   VPBlockUtils::insertBlockAfter(TopRegion, VecPreheader);
   VPBasicBlock *MiddleVPBB = new VPBasicBlock("middle.block");
   VPBlockUtils::insertBlockAfter(MiddleVPBB, TopRegion);
+
+  // Add a check in the middle block to see if we have completed
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ayalz wrote:

```suggestion
  VPBasicBlock *ScalarPH = new VPBasicBlock("scalar.ph");
  
  // If needed, add a check in the middle block to see if we have completed
```

https://github.com/llvm/llvm-project/pull/92651