[llvm] [VPlan] Simplify before covnertToConcreteRecipes, remove SCALAR-STEPS. (PR #123655)

[David Sherwood via llvm-commits]

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@@ -7652,6 +7652,8 @@ DenseMap<const SCEV *, Value *> LoopVectorizationPlanner::executePlan(
   VPlanTransforms::unrollByUF(BestVPlan, BestUF,
                               OrigLoop->getHeader()->getContext());
   VPlanTransforms::optimizeForVFAndUF(BestVPlan, BestVF, BestUF, PSE);
+  VPlanTransforms::simplifyRecipes(BestVPlan, Legal->getWidestInductionType());
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david-arm wrote:

It looks like the code to refactor simplifyRecipes could actually be its own NFC patch, right?

https://github.com/llvm/llvm-project/pull/123655