[llvm] [VPlan] zext canonical IV in convertToStridedAccesses (PR #212291)

[Florian Hahn via llvm-commits]

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@@ -5815,7 +5815,7 @@ void VPlanTransforms::convertToStridedAccesses(VPlan &Plan,
       Type *IndexTy = Plan.getDataLayout().getIndexType(Ptr->getScalarType());
       assert(IndexTy == StrideInBytes->getScalarType() &&
              "Stride type from SCEV must match the index type");
-      VPValue *CanIV = Builder.createScalarSExtOrTrunc(
+      VPValue *CanIV = Builder.createScalarZExtOrTrunc(
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fhahn wrote:

Ah yes, right.

Another thing , it looks like `sext` for the cases in `llvm/test/Transforms/LoopVectorize/RISCV/strided-accesses-narrow-iv.ll` is only correct because the narrow IV does not signed wrap. It looks like we don't vectorize with strided loads if it would wrap, but this may be something to keep an eye out for

https://github.com/llvm/llvm-project/pull/212291