[clang] [llvm] [RISCV] Support version 0.9 of Zvabd (PR #218576)

[Pengcheng Wang via llvm-commits]

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@@ -836,6 +836,29 @@ let TargetPrefix = "riscv" in {
     let ScalarOperand = 1;
     let VLOperand = 4;
   }
+  // UnMasked Widening Vector Absolute-Difference-Accumulate operations,
+  // its first operand can not be undef.
+  // Input: (vector_in, vector_in, vector_in/scalar, vl, policy)
+  class RISCVTernaryWideVS2FirstUnMasked
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wangpc-pp wrote:

Reuse RISCVVDOT4AUnMasked/RISCVVDOT4AMasked?
https://github.com/riscv/riscv-isa-manual/pull/3279#issuecomment-5427592170

https://github.com/llvm/llvm-project/pull/218576