[TTI] Move vp.{select,merge} costing from RISCV to BasicTTIImpl. NFC (#147870)

Move the costing to the generic implementation in BasicTTIImpl since it
just falls back to the non-vp costing.

Also pass through the OperandValueInfo if using value based costing, but
I don't believe this affects the result for any in-tree target
currently.

Author: lukel97

llvm/include/llvm/CodeGen/BasicTTIImpl.h

@@ -1773,6 +1773,18 @@ class BasicTTIImplBase : public TargetTransformInfoImplCRTPBase<T> {
         }
       }
 
+      if (ICA.getID() == Intrinsic::vp_select ||
+          ICA.getID() == Intrinsic::vp_merge) {
+        TTI::OperandValueInfo OpInfoX, OpInfoY;
+        if (!ICA.isTypeBasedOnly()) {
+          OpInfoX = TTI::getOperandInfo(ICA.getArgs()[0]);
+          OpInfoY = TTI::getOperandInfo(ICA.getArgs()[1]);
+        }
+        return getCmpSelInstrCost(
+            Instruction::Select, ICA.getReturnType(), ICA.getArgTypes()[0],
+            CmpInst::BAD_ICMP_PREDICATE, CostKind, OpInfoX, OpInfoY);
+      }
+
       std::optional<Intrinsic::ID> FID =
           VPIntrinsic::getFunctionalIntrinsicIDForVP(ICA.getID());
       if (FID) {

llvm/lib/Target/RISCV/RISCVTargetTransformInfo.cpp

@@ -1512,17 +1512,6 @@ RISCVTTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
       return Cost * LT.first;
     break;
   }
-  case Intrinsic::vp_select: {
-    Intrinsic::ID IID = ICA.getID();
-    std::optional<unsigned> FOp = VPIntrinsic::getFunctionalOpcodeForVP(IID);
-    assert(FOp.has_value());
-    return getCmpSelInstrCost(*FOp, ICA.getReturnType(), ICA.getArgTypes()[0],
-                              CmpInst::BAD_ICMP_PREDICATE, CostKind);
-  }
-  case Intrinsic::vp_merge:
-    return getCmpSelInstrCost(Instruction::Select, ICA.getReturnType(),
-                              ICA.getArgTypes()[0], CmpInst::BAD_ICMP_PREDICATE,
-                              CostKind);
   case Intrinsic::experimental_vp_splat: {
     auto LT = getTypeLegalizationCost(RetTy);
     // TODO: Lower i1 experimental_vp_splat