[llvm] [VPlan] Add helper to run VPlan passes, verify after run (NFC). (PR #123640)

[Luke Lau via llvm-commits]

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@@ -9817,10 +9833,10 @@ void LoopVectorizationPlanner::adjustRecipesForReductions(
       PhiR->setOperand(0, Plan->getOrAddLiveIn(RdxDesc.getSentinelValue()));
     }
   }
-
-  VPlanTransforms::clearReductionWrapFlags(*Plan);
   for (VPRecipeBase *R : ToDelete)
     R->eraseFromParent();
+
+  VPlanTransforms::runPass(VPlanTransforms::clearReductionWrapFlags, *Plan);
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lukel97 wrote:

I presume we needed to move `clearReductionWrapFlags` after the dead recipes were deleted to satisfy the verifier?

https://github.com/llvm/llvm-project/pull/123640