[llvm] [PowerPC] Add custom lowering for ssubo (PR #111748)

[Lei Huang via llvm-commits]

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@@ -12038,6 +12073,8 @@ SDValue PPCTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   case ISD::SETCC:              return LowerSETCC(Op, DAG);
   case ISD::INIT_TRAMPOLINE:    return LowerINIT_TRAMPOLINE(Op, DAG);
   case ISD::ADJUST_TRAMPOLINE:  return LowerADJUST_TRAMPOLINE(Op, DAG);
+  case ISD::SSUBO:
+    return LowerSSUBO(Op, DAG);
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lei137 wrote:

nit: should we just follow the same fmt as the other lines?  I realize it's not clang-format approved...

https://github.com/llvm/llvm-project/pull/111748