[llvm] [VPlan] Replace ExtractLast(Elem|LanePerPart) with ExtractLast(Lane/Part) (PR #164124)

[via llvm-commits]

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@@ -491,12 +496,10 @@ cloneForLane(VPlan &Plan, VPBuilder &Builder, Type *IdxTy,
       continue;
     }
     if (Lane.getKind() == VPLane::Kind::ScalableLast) {
-      // Look through mandatory Unpack.
-      [[maybe_unused]] bool Matched =
-          match(Op, m_VPInstruction<VPInstruction::Unpack>(m_VPValue(Op)));
-      assert(Matched && "original op must have been Unpack");
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ayalz wrote:

Why is the assert dropped?

https://github.com/llvm/llvm-project/pull/164124