[llvm] [AMDGPU] Remove setcc by using add/sub carryout (PR #155255)

[Matt Arsenault via llvm-commits]

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@@ -5944,6 +5944,9 @@ SITargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
     return lowerWaveReduce(MI, *BB, *getSubtarget(), AMDGPU::S_XOR_B64);
   case AMDGPU::S_UADDO_PSEUDO:
   case AMDGPU::S_USUBO_PSEUDO: {
+    MachineRegisterInfo &MRI = BB->getParent()->getRegInfo();
+    const GCNSubtarget &ST = MF->getSubtarget<GCNSubtarget>();
+    const SIRegisterInfo *TRI = ST.getRegisterInfo();
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arsenm wrote:

```suggestion
    MachineRegisterInfo &MRI = BB->getParent()->getRegInfo();
    const SIRegisterInfo *TRI = Subtarget->getRegisterInfo();
```

https://github.com/llvm/llvm-project/pull/155255