[llvm-branch-commits] [llvm] [VPlan] Explicitly handle scalar pointer inductions. (PR #80273)

[Florian Hahn via llvm-branch-commits]

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@@ -537,6 +542,30 @@ void VPlanTransforms::optimizeInductions(VPlan &Plan, ScalarEvolution &SE) {
   bool HasOnlyVectorVFs = !Plan.hasVF(ElementCount::getFixed(1));
   VPBasicBlock::iterator InsertPt = HeaderVPBB->getFirstNonPhi();
   for (VPRecipeBase &Phi : HeaderVPBB->phis()) {
+    if (auto *PtrIV = dyn_cast<VPWidenPointerInductionRecipe>(&Phi)) {
+      if (!PtrIV->onlyScalarsGenerated(Plan.hasScalableVF()))
+        continue;
+
+      const InductionDescriptor &ID = PtrIV->getInductionDescriptor();
+      VPValue *StartV = Plan.getVPValueOrAddLiveIn(
+          ConstantInt::get(ID.getStep()->getType(), 0));
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fhahn wrote:

The start value of the pointer induction is the pointer base, but here we need the start value for the generate offsets.

https://github.com/llvm/llvm-project/pull/80273