From dcc86d5bb60baf79d8875a4b0b0d36902d542fc3 Mon Sep 17 00:00:00 2001 From: Elena Demikhovsky Date: Wed, 7 Sep 2016 20:54:33 +0000 Subject: Shift-left (ISD::SHL) operation crashes on "DAG Legalization" phase. https://llvm.org/bugs/show_bug.cgi?id=29058. While node legalization we tried to legalize its operands. If an operand node is replaced during legalization the user node may be destroyed. Differential Revision: https://reviews.llvm.org/D24244 llvm-svn: 280862 --- llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 48 +++++++++++++++------------ 1 file changed, 27 insertions(+), 21 deletions(-) (limited to 'llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp') diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp index 71e9197b41c..9c560541d13 100644 --- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -1067,35 +1067,41 @@ void SelectionDAGLegalize::LegalizeOp(SDNode *Node) { case ISD::SRL: case ISD::SRA: case ISD::ROTL: - case ISD::ROTR: + case ISD::ROTR: { // Legalizing shifts/rotates requires adjusting the shift amount // to the appropriate width. - if (!Node->getOperand(1).getValueType().isVector()) { - SDValue SAO = - DAG.getShiftAmountOperand(Node->getOperand(0).getValueType(), - Node->getOperand(1)); - HandleSDNode Handle(SAO); - LegalizeOp(SAO.getNode()); - NewNode = DAG.UpdateNodeOperands(Node, Node->getOperand(0), - Handle.getValue()); + SDValue Op0 = Node->getOperand(0); + SDValue Op1 = Node->getOperand(1); + if (!Op1.getValueType().isVector()) { + SDValue SAO = DAG.getShiftAmountOperand(Op0.getValueType(), Op1); + // The getShiftAmountOperand() may create a new operand node or + // return the existing one. If new operand is created we need + // to update the parent node. + // Do not try to legalize SAO here! It will be automatically legalized + // in the next round. + if (SAO != Op1) + NewNode = DAG.UpdateNodeOperands(Node, Op0, SAO); } - break; + } + break; case ISD::SRL_PARTS: case ISD::SRA_PARTS: - case ISD::SHL_PARTS: + case ISD::SHL_PARTS: { // Legalizing shifts/rotates requires adjusting the shift amount // to the appropriate width. - if (!Node->getOperand(2).getValueType().isVector()) { - SDValue SAO = - DAG.getShiftAmountOperand(Node->getOperand(0).getValueType(), - Node->getOperand(2)); - HandleSDNode Handle(SAO); - LegalizeOp(SAO.getNode()); - NewNode = DAG.UpdateNodeOperands(Node, Node->getOperand(0), - Node->getOperand(1), - Handle.getValue()); + SDValue Op0 = Node->getOperand(0); + SDValue Op1 = Node->getOperand(1); + SDValue Op2 = Node->getOperand(2); + if (!Op2.getValueType().isVector()) { + SDValue SAO = DAG.getShiftAmountOperand(Op0.getValueType(), Op2); + // The getShiftAmountOperand() may create a new operand node or + // return the existing one. If new operand is created we need + // to update the parent node. + if (SAO != Op2) + NewNode = DAG.UpdateNodeOperands(Node, Op0, Op1, SAO); } - break; + } + break; } if (NewNode != Node) { -- cgit v1.2.3