[llvm] [RISCV][TTI] Implement cost for vp min/max intrinsics (PR #107567)

[Shih-Po Hung via llvm-commits]

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@@ -989,6 +989,14 @@ RISCVTTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
       return Cost * LT.first;
     break;
   }
+  case Intrinsic::vp_smax:
+  case Intrinsic::vp_smin:
+  case Intrinsic::vp_umax:
+  case Intrinsic::vp_umin: {
+    auto LT = getTypeLegalizationCost(RetTy);
+    return LT.first *
+           getRISCVInstructionCost(RISCV::VMAXU_VV, LT.second, CostKind);
----------------
arcbbb wrote:

Do you suggest extending the RISCV opcode list like this?
```diff
+enum RVVOpcode {
+  VMIN_MAX_VV = RISCV::INSTRUCTION_LIST_END+1,
+};
+
```

https://github.com/llvm/llvm-project/pull/107567