[llvm] [VPlan] Make canonical IV part of the region (PR #156262)

[via llvm-commits]

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@@ -395,7 +395,7 @@ static bool canonicalHeaderAndLatch(VPBlockBase *HeaderVPB,
 /// Create a new VPRegionBlock for the loop starting at \p HeaderVPB.
 static void createLoopRegion(VPlan &Plan, VPBlockBase *HeaderVPB) {
   auto *PreheaderVPBB = HeaderVPB->getPredecessors()[0];
-  auto *LatchVPBB = HeaderVPB->getPredecessors()[1];
+  auto *LatchVPBB = cast<VPBasicBlock>(HeaderVPB->getPredecessors()[1]);
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ayalz wrote:

Why/Is this needed?

https://github.com/llvm/llvm-project/pull/156262