diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index c7cc6916ab96..8077709c94ab 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1543,9 +1543,6 @@ SDOperand DAGCombiner::visitSIGN_EXTEND(SDNode *N) { // fold (sext (sext x)) -> (sext x) if (N0.getOpcode() == ISD::SIGN_EXTEND) return DAG.getNode(ISD::SIGN_EXTEND, VT, N0.getOperand(0)); - // fold (sext (sextload x)) -> (sextload x) - if (N0.getOpcode() == ISD::SEXTLOAD && VT == N0.getValueType()) - return N0; // fold (sext (truncate x)) -> (sextinreg x) iff x size == sext size. if (N0.getOpcode() == ISD::TRUNCATE && N0.getOperand(0).getValueType() == VT&& (!AfterLegalize || @@ -1562,6 +1559,20 @@ SDOperand DAGCombiner::visitSIGN_EXTEND(SDNode *N) { ExtLoad.getValue(1)); return SDOperand(); } + + // fold (sext (sextload x)) -> (sext (truncate (sextload x))) + // fold (sext ( extload x)) -> (sext (truncate (sextload x))) + if ((N0.getOpcode() == ISD::SEXTLOAD || N0.getOpcode() == ISD::EXTLOAD) && + N0.hasOneUse()) { + SDOperand ExtLoad = DAG.getNode(ISD::SEXTLOAD, VT, N0.getOperand(0), + N0.getOperand(1), N0.getOperand(2), + N0.getOperand(3)); + WorkList.push_back(N); + CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad), + ExtLoad.getValue(1)); + return SDOperand(); + } + return SDOperand(); } @@ -1576,12 +1587,9 @@ SDOperand DAGCombiner::visitZERO_EXTEND(SDNode *N) { // fold (zext (zext x)) -> (zext x) if (N0.getOpcode() == ISD::ZERO_EXTEND) return DAG.getNode(ISD::ZERO_EXTEND, VT, N0.getOperand(0)); - // fold (zext (zextload x)) -> (zextload x) - if (N0.getOpcode() == ISD::ZEXTLOAD && VT == N0.getValueType()) - return N0; // fold (zext (truncate x)) -> (zextinreg x) iff x size == zext size. if (N0.getOpcode() == ISD::TRUNCATE && N0.getOperand(0).getValueType() == VT&& - !AfterLegalize) + (!AfterLegalize || TLI.isOperationLegal(ISD::AND, N0.getValueType()))) return DAG.getZeroExtendInReg(N0.getOperand(0), N0.getValueType()); // fold (zext (load x)) -> (zext (truncate (zextload x))) if (N0.getOpcode() == ISD::LOAD && N0.hasOneUse()) { @@ -1593,6 +1601,19 @@ SDOperand DAGCombiner::visitZERO_EXTEND(SDNode *N) { ExtLoad.getValue(1)); return SDOperand(); } + + // fold (zext (zextload x)) -> (zext (truncate (zextload x))) + // fold (zext ( extload x)) -> (zext (truncate (zextload x))) + if ((N0.getOpcode() == ISD::ZEXTLOAD || N0.getOpcode() == ISD::EXTLOAD) && + N0.hasOneUse()) { + SDOperand ExtLoad = DAG.getNode(ISD::ZEXTLOAD, VT, N0.getOperand(0), + N0.getOperand(1), N0.getOperand(2), + N0.getOperand(3)); + WorkList.push_back(N); + CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad), + ExtLoad.getValue(1)); + return SDOperand(); + } return SDOperand(); }