diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Target/X86/X86ISelDAGToDAG.cpp | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp index b4c71548a2..98778c3091 100644 --- a/lib/Target/X86/X86ISelDAGToDAG.cpp +++ b/lib/Target/X86/X86ISelDAGToDAG.cpp @@ -362,7 +362,7 @@ X86DAGToDAGISel::IsProfitableToFold(SDValue N, SDNode *U, SDNode *Root) const { /// MoveBelowCallOrigChain - Replace the original chain operand of the call with /// load's chain operand and move load below the call's chain operand. static void MoveBelowOrigChain(SelectionDAG *CurDAG, SDValue Load, - SDValue Call, SDValue OrigChain) { + SDValue Call, SDValue OrigChain) { SmallVector<SDValue, 8> Ops; SDValue Chain = OrigChain.getOperand(0); if (Chain.getNode() == Load.getNode()) @@ -386,11 +386,22 @@ static void MoveBelowOrigChain(SelectionDAG *CurDAG, SDValue Load, CurDAG->UpdateNodeOperands(OrigChain.getNode(), &Ops[0], Ops.size()); CurDAG->UpdateNodeOperands(Load.getNode(), Call.getOperand(0), Load.getOperand(1), Load.getOperand(2)); + + bool IsGlued = Call.getOperand(0).getNode()->getGluedUser() == Call.getNode(); + unsigned NumOps = Call.getNode()->getNumOperands(); Ops.clear(); Ops.push_back(SDValue(Load.getNode(), 1)); - for (unsigned i = 1, e = Call.getNode()->getNumOperands(); i != e; ++i) + for (unsigned i = 1, e = NumOps; i != e; ++i) Ops.push_back(Call.getOperand(i)); - CurDAG->UpdateNodeOperands(Call.getNode(), &Ops[0], Ops.size()); + if (!IsGlued) + CurDAG->UpdateNodeOperands(Call.getNode(), &Ops[0], NumOps); + else + // If call's chain was glued to the call (tailcall), and now the load + // is moved between them. Remove the glue to avoid a cycle (where the + // call is glued to its old chain and the load is using the old chain + // as its new chain). + CurDAG->MorphNodeTo(Call.getNode(), Call.getOpcode(), + Call.getNode()->getVTList(), &Ops[0], NumOps-1); } /// isCalleeLoad - Return true if call address is a load and it can be |