[llvm] [VPlan] Explicitly handle scalar pointer inductions. (PR #83068)

[via llvm-commits]

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@@ -1164,11 +1168,23 @@ class VPInstruction : public VPRecipeWithIRFlags {
   /// An optional name that can be used for the generated IR instruction.
   const std::string Name;
 
-  /// Utility method serving execute(): generates a single instance of the
-  /// modeled instruction. \returns the generated value for \p Part.
-  /// In some cases an existing value is returned rather than a generated
+  /// Returns true if this VPInstruction generates scalar values for all lanes.
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ayalz wrote:

Adding some context? E.g.,
// Most VPInstructions generate a single value per part, either vector or scalar. VPReplicateRecipe takes care of generating multiple (scalar) values per all lanes, stemming from an original ingredient. This method identifies the (rare) cases of VPInstructions that do so as well, w/o an underlying ingredient.

https://github.com/llvm/llvm-project/pull/83068