[llvm] [VPlan] Add VPExpressionRecipe, replacing extended reduction recipes. (PR #144281)

[via llvm-commits]

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@@ -49,6 +49,7 @@ class VPValue {
   friend struct VPDoubleValueDef;
   friend class VPInterleaveRecipe;
   friend class VPlan;
+  friend class VPExpressionRecipe;
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ayalz wrote:

Lex order?

https://github.com/llvm/llvm-project/pull/144281