[llvm] [VPlan] Model FOR extract of exit value in VPlan. (PR #93395)

[via llvm-commits]

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@@ -558,6 +560,27 @@ Value *VPInstruction::generatePerPart(VPTransformState &State, unsigned Part) {
 
     return ReducedPartRdx;
   }
+  case VPInstruction::ExtractRecurrenceResult: {
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ayalz wrote:

Such a VPInstruction seems independent of Recurrence Result, and could hopefully be used elsewhere if generalized(?).
How about calling it `ExtractPenultimateElement`? Or ExtractElementFromEnd with another operand conveying which element to extract, from the end...
Admittedly hard to see reuse opportunities atm, but better focus on what it does than what it's used for?

https://github.com/llvm/llvm-project/pull/93395