[llvm] [RISCV][CostModel][NFC] Add getRISCVInstructionCost() to TTI for Cost… (PR #73651)

[Wang Pengcheng via llvm-commits]

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@@ -34,6 +34,53 @@ static cl::opt<unsigned> SLPMaxVF(
         "exclusively by SLP vectorizer."),
     cl::Hidden);
 
+InstructionCost
+RISCVTTIImpl::getRISCVInstructionCost(RISCVInstruction Inst, MVT VT,
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wangpc-pp wrote:

What about making it `getRISCVInstructionCost(ArrayRef<RISCVInstruction> Insts, MVT VT, TTI::TargetCostKind CostKind)` and calculate the cost sum of `Insts`?

https://github.com/llvm/llvm-project/pull/73651