[llvm] [LV] Support EVL for partial reduction and VPExpressionRecipe. (PR #205741)

[Mel Chen via llvm-commits]

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@@ -3655,10 +3656,13 @@ class VPExpressionRecipe : public VPSingleDefRecipe {
     return getOperand(getNumOperands() - OpIdx);
   }
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Mel-Chen wrote:

This function should be affected. However, since it currently has no users, maybe we could consider removing it?

https://github.com/llvm/llvm-project/pull/205741