diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 6fb5e3996e2..7a34179ad32 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -5273,6 +5273,10 @@ SDValue DAGCombiner::visitRotate(SDNode *N) { SDValue N1 = N->getOperand(1); EVT VT = N->getValueType(0); + // fold (rot x, 0) -> x + if (isNullConstantOrNullSplatConstant(N1)) + return N0; + // fold (rot* x, (trunc (and y, c))) -> (rot* x, (and (trunc y), (trunc c))). if (N1.getOpcode() == ISD::TRUNCATE && N1.getOperand(0).getOpcode() == ISD::AND) { |
