diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 5315d9e11f5..533fd70de02 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -786,10 +786,11 @@ SDOperand DAGCombiner::visitUDIV(SDNode *N) { if (ConstantSDNode *SHC = dyn_cast(N1.getOperand(0))) { if (isPowerOf2_64(SHC->getValue())) { MVT::ValueType ADDVT = N1.getOperand(1).getValueType(); - return DAG.getNode(ISD::SRL, VT, N0, - DAG.getNode(ISD::ADD, ADDVT, N1.getOperand(1), - DAG.getConstant(Log2_64(SHC->getValue()), - ADDVT))); + SDOperand Add = DAG.getNode(ISD::ADD, ADDVT, N1.getOperand(1), + DAG.getConstant(Log2_64(SHC->getValue()), + ADDVT)); + WorkList.push_back(Add.Val); + return DAG.getNode(ISD::SRL, VT, N0, Add); } } } @@ -833,6 +834,16 @@ SDOperand DAGCombiner::visitUREM(SDNode *N) { // fold (urem x, pow2) -> (and x, pow2-1) if (N1C && !N1C->isNullValue() && isPowerOf2_64(N1C->getValue())) return DAG.getNode(ISD::AND, VT, N0, DAG.getConstant(N1C->getValue()-1,VT)); + // fold (urem x, (shl pow2, y)) -> (and x, (add (shl pow2, y), -1)) + if (N1.getOpcode() == ISD::SHL) { + if (ConstantSDNode *SHC = dyn_cast(N1.getOperand(0))) { + if (isPowerOf2_64(SHC->getValue())) { + SDOperand Add = DAG.getNode(ISD::ADD, VT, N1, DAG.getConstant(-1, VT)); + WorkList.push_back(Add.Val); + return DAG.getNode(ISD::AND, VT, N0, Add); + } + } + } return SDOperand(); }