[llvm] [ARM] Enable creation of ARMISD::CMN nodes (PR #163223)

[via llvm-commits]

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@@ -250,7 +250,7 @@ def ARMBcci64        : SDNode<"ARMISD::BCC_i64", SDT_ARMBCC_i64,
 def ARMcmp           : SDNode<"ARMISD::CMP", SDT_ARMCmp>;
 
 // ARM CMN instructions.
-def ARMcmn           : SDNode<"ARMISD::CMN", SDT_ARMCmp>;
+def ARMcmn           : SDNode<"ARMISD::CMN", SDT_ARMCmp, [SDNPCommutative]>;
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SiliconA-Z wrote:

[SDNPCommutative] fits because CMN is addition, and it should stay in this patch because it’s part of defining the ARMcmn SDNode correctly, not a separate optimization.

https://github.com/llvm/llvm-project/pull/163223