[llvm] [VPlan] Replicate VPScalarIVStepsRecipe by VF outside replicate regions. (PR #170053)

[via llvm-commits]

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@@ -4049,6 +4052,14 @@ class LLVM_ABI_FOR_TEST VPScalarIVStepsRecipe : public VPRecipeWithIRFlags {
     return getNumOperands() == 4 ? getOperand(3) : nullptr;
   }
 
+  /// Set or add the StartIndex operand.
+  void resetStartIndex(VPValue *StartIndex) {
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ayalz wrote:

```suggestion
  void setStartIndex(VPValue *StartIndex) {
```
as this takes care of both initial setting and subsequent resetting?

https://github.com/llvm/llvm-project/pull/170053