[llvm] [VPlan] CSE ExpandSCEV recipes (PR #208953)

[Luke Lau via llvm-commits]

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@@ -2936,6 +2925,8 @@ void VPlanTransforms::optimize(VPlan &Plan) {
   RUN_VPLAN_PASS(createAndOptimizeReplicateRegions, Plan);
   RUN_VPLAN_PASS(mergeBlocksIntoPredecessors, Plan);
   RUN_VPLAN_PASS(licm, Plan);
+  RUN_VPLAN_PASS(cse, Plan);
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lukel97 wrote:

This is now running cse before costing. I might be misremembering but we tried to do this before and ran into some issue, but this was a while ago. Can this be split into its own PR so we can evaluate it separately?

https://github.com/llvm/llvm-project/pull/208953