llvm-project

863e17a5 - [VPlan] Make Phi operand for VPReductionPHIRecipe optional (NFC).

[VPlan] Make Phi operand for VPReductionPHIRecipe optional (NFC). VPReductionPHIRecipe doesn't rely on the underlying phi any longer, allow empty underlying values when cloning. NFC at the moment but will enable follow-up patches.