[llvm] [VPlan] Simplify branch on False in VPlan transform (NFC). (PR #140409)

[via llvm-commits]

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@@ -507,8 +507,12 @@ void VPlanTransforms::prepareForVectorization(
                                    cast<VPBasicBlock>(HeaderVPB),
                                    cast<VPBasicBlock>(LatchVPB), Range);
         HandledUncountableEarlyExit = true;
+      } else {
+        for (VPRecipeBase &R : cast<VPIRBasicBlock>(EB)->phis()) {
+          if (auto *PhiR = dyn_cast<VPIRPhi>(&R))
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ayalz wrote:

Can R be anything but a VPIRPhi?

https://github.com/llvm/llvm-project/pull/140409