[llvm] [LoongArch] Optimize codegen for ISD::{ROTL,ROTR} (PR #91174)

[via llvm-commits]

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@@ -1715,6 +1712,26 @@ static SDValue customLegalizeToWOp(SDNode *N, SelectionDAG &DAG, int NumOp,
   return DAG.getNode(ISD::TRUNCATE, DL, N->getValueType(0), NewRes);
 }
 
+static SDValue customLegalizeToRotateWOp(SDNode *N, SelectionDAG &DAG,
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wangleiat wrote:

Can we try to reuse  `customLegalizeToWOp`?

https://github.com/llvm/llvm-project/pull/91174