[llvm] [RISCV] Add cost for @llvm.experimental.vp.splat (PR #117313)

[Luke Lau via llvm-commits]

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@@ -1155,6 +1155,11 @@ RISCVTTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
     return getCmpSelInstrCost(Instruction::Select, ICA.getReturnType(),
                               ICA.getArgTypes()[0], CmpInst::BAD_ICMP_PREDICATE,
                               CostKind);
+  case Intrinsic::experimental_vp_splat: {
+    auto LT = getTypeLegalizationCost(RetTy);
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lukel97 wrote:

Sounds good. I've made it return invalid rather than falling out of the switch since we can't scalarize scalable nor fixed versions of this intrinsic yet

https://github.com/llvm/llvm-project/pull/117313