[llvm] [AArch64][SVE] Mark AES instructions commutable. (PR #142919)

[Paul Walker via llvm-commits]

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@@ -9254,7 +9254,9 @@ class sve2_crypto_des_bin_op<bits<2> opc, string asm, ZPRRegOp zprty>
 }
 
 multiclass sve2_crypto_des_bin_op<bits<2> opc, string asm, ZPRRegOp zprty,
-                                  SDPatternOperator op, ValueType vt> {
+                                  SDPatternOperator op, ValueType vt,
+                                  bit commutable = 0> {
+  let isCommutable = commutable in
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paulwalker-arm wrote:

No, worst come to worst I'll be happy with the current approach.

Just before that though... The multiclass only has a single pattern and we're unlikely to add more so I think you can remove the multiclass and change the main class's DAG from `[]` to  `[(set (vt zprty:$Zdn), (op (vt zprty:$_Zdn), (vt zprty:$Zm)))]` and then you'll be able to wrap the relevant definitions with `isCommutable`.

https://github.com/llvm/llvm-project/pull/142919