[llvm] [RISCV][ISel] Fold trunc (lshr (add (zext X), (zext Y)), 1) -> vaaddu X, Y (PR #76550)

[via llvm-commits]

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@@ -115,6 +124,7 @@ def riscv_saddsat_vl   : SDNode<"RISCVISD::SADDSAT_VL", SDT_RISCVIntBinOp_VL, [S
 def riscv_uaddsat_vl   : SDNode<"RISCVISD::UADDSAT_VL", SDT_RISCVIntBinOp_VL, [SDNPCommutative]>;
 def riscv_ssubsat_vl   : SDNode<"RISCVISD::SSUBSAT_VL", SDT_RISCVIntBinOp_VL>;
 def riscv_usubsat_vl   : SDNode<"RISCVISD::USUBSAT_VL", SDT_RISCVIntBinOp_VL>;
+def riscv_uavgadd_vl   : SDNode<"RISCVISD::UAVGADD_VL", SDT_RISCVIntBinOp_RM_VL, [SDNPCommutative]>;
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sun-jacobi wrote:

Thank for your detailed advice. I will try this way.

https://github.com/llvm/llvm-project/pull/76550