[llvm] [AArch64] Improve fixed vector lowering for cttz/ctlz when sve (PR #192427)

[Paul Walker via llvm-commits]

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@@ -1982,11 +1984,14 @@ AArch64TargetLowering::AArch64TargetLowering(const TargetMachine &TM,
       for (auto VT : {MVT::v8i8, MVT::v16i8, MVT::v4i16, MVT::v8i16,
                       MVT::v2i32, MVT::v4i32, MVT::v2i64}) {
         setOperationAction(ISD::BITREVERSE, VT, Custom);
-        setOperationAction(ISD::CTTZ, VT, Custom);
         setOperationAction(ISD::VECREDUCE_AND, VT, Custom);
         setOperationAction(ISD::VECREDUCE_OR, VT, Custom);
         setOperationAction(ISD::VECREDUCE_XOR, VT, Custom);
       }
+      for (auto VT : {MVT::v8i8, MVT::v16i8, MVT::v4i16, MVT::v8i16, MVT::v2i32,
+                      MVT::v4i32}) {
+        setOperationAction(ISD::CTTZ, VT, Custom);
+      }
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paulwalker-arm wrote:

After the rebase this shouldn't be necessary anymore because it is the behaviour already set by NEON.

https://github.com/llvm/llvm-project/pull/192427