[llvm] [VPlan] Materialize Build(Struct)Vectors for VPReplicateRecipes. (NFCI) (PR #151487)

[via llvm-commits]

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@@ -524,36 +536,45 @@ void VPlanTransforms::replicateByVF(VPlan &Plan, ElementCount VF) {
         if (isa<StoreInst>(RepR->getUnderlyingInstr()) &&
             vputils::isSingleScalar(RepR->getOperand(1))) {
           // Stores to invariant addresses need to store the last lane only.
-          cloneForLane(Plan, Builder, IdxTy, RepR,
-                       VPLane::getLastLaneForVF(VF));
+          cloneForLane(Plan, Builder, IdxTy, RepR, VPLane::getLastLaneForVF(VF),
+                       Def2LaneDefs);
         } else {
           // Create single-scalar version of RepR for all lanes.
           for (unsigned I = 0; I != VF.getKnownMinValue(); ++I)
-            cloneForLane(Plan, Builder, IdxTy, RepR, VPLane(I));
+            cloneForLane(Plan, Builder, IdxTy, RepR, VPLane(I), Def2LaneDefs);
         }
         RepR->eraseFromParent();
         continue;
       }
       /// Create single-scalar version of RepR for all lanes.
       SmallVector<VPValue *> LaneDefs;
       for (unsigned I = 0; I != VF.getKnownMinValue(); ++I)
-        LaneDefs.push_back(cloneForLane(Plan, Builder, IdxTy, RepR, VPLane(I)));
+        LaneDefs.push_back(
+            cloneForLane(Plan, Builder, IdxTy, RepR, VPLane(I), Def2LaneDefs));
 
+      Def2LaneDefs[RepR] = LaneDefs;
       /// Users that only demand the first lane can use the definition for lane
       /// 0.
       RepR->replaceUsesWithIf(LaneDefs[0], [RepR](VPUser &U, unsigned) {
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ayalz wrote:

Note that the RUWI of removes users of RepR that use only its first lane.

https://github.com/llvm/llvm-project/pull/151487