[llvm] df0c16c - [NFC][DAGCombine] Use isOperandOf() in combineCarryDiamond

[Paweł Bylica via llvm-commits]

Author: Paweł Bylica
Date: 2022-02-21T21:41:31+01:00
New Revision: df0c16ce00629dd55d85ece34403535c39c1da9d

URL: https://github.com/llvm/llvm-project/commit/df0c16ce00629dd55d85ece34403535c39c1da9d
DIFF: https://github.com/llvm/llvm-project/commit/df0c16ce00629dd55d85ece34403535c39c1da9d.diff

LOG: [NFC][DAGCombine] Use isOperandOf() in combineCarryDiamond

Pre-commit for https://reviews.llvm.org/D118362.

Added: 
    

Modified: 
    llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 3196ba9f7689d..6c5286277ba9d 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -3146,12 +3146,12 @@ static SDValue combineCarryDiamond(SelectionDAG &DAG, const TargetLowering &TLI,
   if (Opcode != ISD::UADDO && Opcode != ISD::USUBO)
     return SDValue();
 
-  // Canonicalize the add/sub of A and B as Carry0 and the add/sub of the
-  // carry/borrow in as Carry1. (The top and middle uaddo nodes respectively in
-  // the above ASCII art.)
-  if (Carry1.getOperand(0) != Carry0.getValue(0) &&
-      Carry1.getOperand(1) != Carry0.getValue(0))
+  // Canonicalize the add/sub of A and B (the top node in the above ASCII art)
+  // as Carry0 and the add/sub of the carry in as Carry1 (the middle node).
+  if (Carry1.getNode()->isOperandOf(Carry0.getNode()))
     std::swap(Carry0, Carry1);
+
+  // Check if nodes are connected in expected way.
   if (Carry1.getOperand(0) != Carry0.getValue(0) &&
       Carry1.getOperand(1) != Carry0.getValue(0))
     return SDValue();