[llvm] [VPlan] Extend getSCEVForVPV, use to compute VPReplicateRecipe cost. (PR #161276)

[Florian Hahn via llvm-commits]

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@@ -3257,9 +3253,12 @@ InstructionCost VPReplicateRecipe::computeCost(ElementCount VF,
 
     Type *PtrTy = isSingleScalar() ? ScalarPtrTy : toVectorTy(ScalarPtrTy, VF);
 
+    const SCEV *PtrSCEV = getAddressAccessSCEV(PtrOp, Ctx.SE, Ctx.L);
+    if (PtrSCEV && isa<SCEVCouldNotCompute>(PtrSCEV))
+      break;
     InstructionCost ScalarCost =
         ScalarMemOpCost + Ctx.TTI.getAddressComputationCost(
-                              PtrTy, &Ctx.SE, nullptr, Ctx.CostKind);
+                              PtrTy, &Ctx.SE, PtrSCEV, Ctx.CostKind);
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fhahn wrote:

This should be covered by a number of tests with replicating stores and the assertion that legacy & VPlan cost model agree

https://github.com/llvm/llvm-project/pull/161276