[llvm] [VPlan] Add transformation to narrow interleave groups. (PR #106441)

[Florian Hahn via llvm-commits]

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@@ -954,7 +954,6 @@ void VPlan::prepareToExecute(Value *TripCountV, Value *VectorTripCountV,
 
   IRBuilder<> Builder(State.CFG.PrevBB->getTerminator());
   // FIXME: Model VF * UF computation completely in VPlan.
-  assert(VFxUF.getNumUsers() && "VFxUF expected to always have users");
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fhahn wrote:

The narrowing changes the loop from stepping by VFxUF to stepping by 1, removing the user of VFxUF. Could only conditionally create it, but I don't think it would cause any test changes, as there only would be a difference for scalable vectors, which isn't supported for narrowing.

https://github.com/llvm/llvm-project/pull/106441