[PATCH] D154522: [DAG] Improve combineCarryDiamond to accept (uaddo_carry X, 0, Carry)

[Paweł Bylica via Phabricator via llvm-commits]

chfast added a comment.

Are you able to add any tests supporting this?



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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:3550
+  SDValue X, Y;
+  bool IsAdd;
+  if (!matchCarry(Carry0, X, Y, IsAdd))
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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:3579
   // Verify that the carry/borrow in is plausibly a carry/borrow bit.
+  // TODO: make getAsCarry() aware of how partial carries are merged.
+  SDValue CarryIn = Carry1.getValue(0) == X ? Y : X;
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This is a came back for this TODO? What exactly does it mean?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D154522/new/

https://reviews.llvm.org/D154522