[llvm] [LV] Vectorize selecting last IV of min/max element. (PR #141431)

[via llvm-commits]

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@@ -214,6 +214,40 @@ static bool checkOrderedReduction(RecurKind Kind, Instruction *ExactFPMathInst,
   return true;
 }
 
+static std::optional<RecurrenceDescriptor>
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ayalz wrote:

Good to document what it's optionally returning.

https://github.com/llvm/llvm-project/pull/141431