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| author | Dan Gohman <gohman@apple.com> | 2007-07-10 15:19:29 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2007-07-10 15:19:29 +0000 |
| commit | adb3d37c07bf4c7911498301af122a260c6da89f (patch) | |
| tree | 5c5037280d3056a5e7b1375734890b7126d138e3 /llvm/lib | |
| parent | bca08114624a046f3c67652d1361121614bce347 (diff) | |
| download | bcm5719-llvm-adb3d37c07bf4c7911498301af122a260c6da89f.tar.gz bcm5719-llvm-adb3d37c07bf4c7911498301af122a260c6da89f.zip | |
Fix a bug in the folding of binary operators to undef.
Thanks to Lauro for spotting this!
llvm-svn: 38491
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 861e5056bb4..e0f0ece9cd5 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/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) |
