[VPlan] Don't assign slots for external defs (NFCI).

External defs are VPValues wrapping an IR value and hence will get
printed as ir<>. We don't need to assign a slot for a VPValue number.

diff --git a/llvm/lib/Transforms/Vectorize/VPlan.cpp b/llvm/lib/Transforms/Vectorize/VPlan.cpp
index 84f577f..4655399 100644 (file)
--- a/llvm/lib/Transforms/Vectorize/VPlan.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlan.cpp
@@ -1108,10 +1108,6 @@ void VPSlotTracker::assignSlot(const VPValue *V) {
 }
 
 void VPSlotTracker::assignSlots(const VPlan &Plan) {
-
-  for (const auto &P : Plan.VPExternalDefs)
-    assignSlot(P.second);
-
   assignSlot(&Plan.VectorTripCount);
   if (Plan.BackedgeTakenCount)
     assignSlot(Plan.BackedgeTakenCount);