[llvm] [VPlan] Create epilogue minimum iteration check in VPlan. (PR #157545)

[via llvm-commits]

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@@ -9766,6 +9701,98 @@ static void fixScalarResumeValuesFromBypass(BasicBlock *BypassBlock, Loop *L,
   }
 }
 
+/// Connect the epilogue vector loop generated for \p Plan to the main vector
+/// loop, updating branches from the iteration and runtime checks, as well as
+/// updating various phis.
+static void connectEpilogueVectorLoop(
+    VPlan &Plan, Loop *L, EpilogueLoopVectorizationInfo &EPI, DominatorTree *DT,
+    LoopVectorizationLegality &LVL,
+    DenseMap<const SCEV *, Value *> &ExpandedSCEVs, GeneratedRTChecks &Checks,
+    ArrayRef<Instruction *> InstsToMove) {
+  BasicBlock *AdditionalBypassBlock =
+      cast<VPIRBasicBlock>(Plan.getEntry())->getIRBasicBlock();
+  BasicBlock *VecEpilogueIterationCountCheck =
+      cast<VPIRBasicBlock>(Plan.getEntry())->getIRBasicBlock();
----------------
ayalz wrote:

```suggestion
  BasicBlock *VecEpilogueIterationCountCheck = AdditionalBypassBlock;
```
?

https://github.com/llvm/llvm-project/pull/157545