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

[Florian Hahn via llvm-commits]

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@@ -936,8 +936,6 @@ void VPlan::prepareToExecute(Value *TripCountV, Value *VectorTripCountV,
 
   IRBuilder<> Builder(State.CFG.PrevBB->getTerminator());
   // FIXME: Model VF * UF computation completely in VPlan.
-  assert((!getVectorLoopRegion() || VFxUF.getNumUsers()) &&
-         "VFxUF expected to always have users");
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fhahn wrote:

It will become `UF` , original version had a bug of always setting it to 1, which is incorrect when interleaving.

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