diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 861e5056bb..e0f0ece9cd 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -855,7 +855,9 @@ SDOperand DAGCombiner::visitADD(SDNode *N) { if (FoldedVOp.Val) return FoldedVOp; // fold (add x, undef) -> undef - if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) + if (N0.getOpcode() == ISD::UNDEF) + return N0; + if (N1.getOpcode() == ISD::UNDEF) return N1; // fold (add c1, c2) -> c1+c2 if (N0C && N1C) @@ -1029,8 +1031,10 @@ SDOperand DAGCombiner::visitSUB(SDNode *N) { if (Result.Val) return Result; } // If either operand of a sub is undef, the result is undef - if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) - return DAG.getNode(ISD::UNDEF, VT); + if (N0.getOpcode() == ISD::UNDEF) + return N0; + if (N1.getOpcode() == ISD::UNDEF) + return N1; return SDOperand(); } @@ -1890,7 +1894,9 @@ SDOperand DAGCombiner::visitXOR(SDNode *N) { if (FoldedVOp.Val) return FoldedVOp; // fold (xor x, undef) -> undef - if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) + if (N0.getOpcode() == ISD::UNDEF) + return N0; + if (N1.getOpcode() == ISD::UNDEF) return N1; // fold (xor c1, c2) -> c1^c2 if (N0C && N1C) |