[llvm] [PowerPC] Deprecate uses of ISD::ADDC/ISD::ADDE/ISD::SUBC/ISD::SUBE (PR #116984)

[Maryam Moghadas via llvm-commits]

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@@ -196,7 +196,11 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
     }
   }
 
+  // PowerPC uses addo,addo_carry,subo,subo_carry to propagate carry.
   setOperationAction(ISD::UADDO, RegVT, Custom);
+  setOperationAction(ISD::USUBO, RegVT, Custom);
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maryammo wrote:

Why using PPCISD::ADDC/ PPCISD::SUBC to lower UADDO/USUBO, instead of using the replacement nodes; ISD::UADDO_CARRY/USUBO_CARRY? (these new nodes are themselves lowered using PPCISD::ADDC/ PPCISD::SUBC) 

https://github.com/llvm/llvm-project/pull/116984