[llvm] [VPlan] Implement interleaving as VPlan-to-VPlan transform. (PR #95842)

[via llvm-commits]

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@@ -9152,42 +9151,59 @@ void VPWidenPointerInductionRecipe::execute(VPTransformState &State) {
 
   auto *IVR = getParent()->getPlan()->getCanonicalIV();
   PHINode *CanonicalIV = cast<PHINode>(State.get(IVR, 0, /*IsScalar*/ true));
+  unsigned CurrentPart = 0;
+  if (getNumOperands() == 5)
+    CurrentPart =
+        cast<ConstantInt>(getOperand(4)->getLiveInIRValue())->getZExtValue();
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ayalz wrote:

Define `CurrentPart` later, closer to where it's needed?

Better record the constant Part as an unsigned field, possibly zero if needed, rather than disrupting the traditional operands?

https://github.com/llvm/llvm-project/pull/95842