[llvm] [VPlan] Run narrowInterleaveGroups during general VPlan optimizations. (PR #149706)

[via llvm-commits]

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@@ -3960,6 +3960,9 @@ void VPlanTransforms::materializeVFAndVFxUF(VPlan &Plan, VPBasicBlock *VectorPH,
   // used.
   // TODO: Assert that they aren't used.
 
+  VPValue *UF = Plan.getOrAddLiveIn(ConstantInt::get(TCTy, Plan.getUF()));
+  Plan.getSymbolicUF().replaceAllUsesWith(UF);
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ayalz wrote:

Better rename `materializeVFAndVFxUF()` now to, say, `materializeVFAndUF()` or `materializeFactors()`?

https://github.com/llvm/llvm-project/pull/149706