[llvm] [AArch64] Use sve instructions for fixed-width smulh/umulh. (PR #166168)

[David Sherwood via llvm-commits]

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@@ -1880,10 +1882,6 @@ AArch64TargetLowering::AArch64TargetLowering(const TargetMachine &TM,
       setOperationAction(ISD::CTLZ, MVT::v1i64, Custom);
       setOperationAction(ISD::CTLZ, MVT::v2i64, Custom);
       setOperationAction(ISD::CTTZ, MVT::v1i64, Custom);
-      setOperationAction(ISD::MULHS, MVT::v1i64, Custom);
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david-arm wrote:

Do we need to delete similar code below on lines 1906-1907?

https://github.com/llvm/llvm-project/pull/166168