diff options
Diffstat (limited to 'llvm/lib/CodeGen/MachineScheduler.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MachineScheduler.cpp | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/llvm/lib/CodeGen/MachineScheduler.cpp b/llvm/lib/CodeGen/MachineScheduler.cpp index 18933a9c2b1..9a7cae6e71f 100644 --- a/llvm/lib/CodeGen/MachineScheduler.cpp +++ b/llvm/lib/CodeGen/MachineScheduler.cpp @@ -1580,12 +1580,14 @@ void CopyConstrain::constrainLocalCopy(SUnit *CopySU, ScheduleDAGMILive *DAG) { MachineInstr *Copy = CopySU->getInstr(); // Check for pure vreg copies. - unsigned SrcReg = Copy->getOperand(1).getReg(); - if (!TargetRegisterInfo::isVirtualRegister(SrcReg)) + const MachineOperand &SrcOp = Copy->getOperand(1); + unsigned SrcReg = SrcOp.getReg(); + if (!TargetRegisterInfo::isVirtualRegister(SrcReg) || !SrcOp.readsReg()) return; - unsigned DstReg = Copy->getOperand(0).getReg(); - if (!TargetRegisterInfo::isVirtualRegister(DstReg)) + const MachineOperand &DstOp = Copy->getOperand(0); + unsigned DstReg = DstOp.getReg(); + if (!TargetRegisterInfo::isVirtualRegister(DstReg) || DstOp.isDead()) return; // Check if either the dest or source is local. If it's live across a back |
