[llvm] [VPlan] Impl VPlan-based pattern match for ExtendedRed and MulAccRed (NFCI) (PR #113903)

[Elvis Wang via llvm-commits]

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@@ -2653,6 +2657,260 @@ class VPReductionEVLRecipe : public VPReductionRecipe {
   }
 };
 
+/// A recipe to represent inloop extended reduction operations, performing a
+/// reduction on a vector operand into a scalar value, and adding the result to
+/// a chain. This recipe is high level abstract which will generate
+/// VPReductionRecipe and VPWidenCastRecipe before execution. The Operands are
+/// {ChainOp, VecOp, [Condition]}.
+class VPExtendedReductionRecipe : public VPSingleDefRecipe {
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ElvisWang123 wrote:

Inherited from VPReductionRecipe, thanks.

https://github.com/llvm/llvm-project/pull/113903