[llvm] [LV] Fix for `VPValue` dump method (PR #94272)

[Kolya Panchenko via llvm-commits]

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@@ -1381,7 +1381,7 @@ void VPSlotTracker::assignNames(const VPlan &Plan) {
   if (Plan.VFxUF.getNumUsers() > 0)
     assignName(&Plan.VFxUF);
   assignName(&Plan.VectorTripCount);
-  if (Plan.BackedgeTakenCount)
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nikolaypanchenko wrote:

not related to crash we saw in downstream compiler, but related to printing and assigning numbers to VPValues as few of our tests started to fail

https://github.com/llvm/llvm-project/pull/94272