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

[Wang Pengcheng via llvm-commits]

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@@ -279,7 +336,8 @@ InstructionCost RISCVTTIImpl::getShuffleCost(TTI::ShuffleKind Kind,
             // Example sequence:
             //   vnsrl.wi   v10, v8, 0
             if (equal(DeinterleaveMask, Mask))
-              return LT.first * TLI->getLMULCost(LT.second);
+              return LT.first * getRISCVInstructionCost({RISCV::VNSRL_WI},
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wangpc-pp wrote:

If there is only one element, we can drop the braces.

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