[llvm] [RISCV][CostModel] Updates reduction and shuffle cost (PR #77342)

[Wang Pengcheng via llvm-commits]

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@@ -84,8 +84,14 @@ RISCVTTIImpl::getRISCVInstructionCost(ArrayRef<unsigned> OpCodes, MVT VT,
       Cost += VL;
       break;
     }
+    case RISCV::VMV_X_S:
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wangpc-pp wrote:

These four cases can be merged.

https://github.com/llvm/llvm-project/pull/77342