[PATCH] D70079: [SelectionDAG] Combine U{ADD,SUB}O diamonds into {ADD,SUB}CARRY

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


================
Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:2831
+// a single path for carry/borrow out propagation:
+static SDValue combineCarryDiamond(DAGCombiner &Combiner, SelectionDAG &DAG,
+                                   const TargetLowering &TLI, SDValue Carry0,
----------------
Just make it a member function?


================
Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:2839-2840
+    return SDValue();
+  if (Opcode != ISD::UADDO && Opcode != ISD::USUBO)
+    return SDValue();
+
----------------
Very last note, i think it would be best to also
```
  if (N->getOpcode() != ISD::AND && N->getOpcode() != ISD::OR && N->getOpcode() != ISD::XOR)
    return SDValue();
```
(or maybe that should be an assert)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D70079/new/

https://reviews.llvm.org/D70079