diff options
Diffstat (limited to 'llvm/lib/CodeGen/MachineSink.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MachineSink.cpp | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp index 54c478645dcf..0dbbc218e946 100644 --- a/llvm/lib/CodeGen/MachineSink.cpp +++ b/llvm/lib/CodeGen/MachineSink.cpp @@ -796,9 +796,14 @@ bool MachineSinking::isProfitableToSinkTo(Register Reg, MachineInstr &MI, if (Reg == 0) continue; - // Don't handle physical register. - if (Register::isPhysicalRegister(Reg)) + if (Register::isPhysicalRegister(Reg)) { + if (MO.isUse() && + (MRI->isConstantPhysReg(Reg) || TII->isIgnorableUse(MO))) + continue; + + // Don't handle non-constant and non-ignorable physical register. return false; + } // Users for the defs are all dominated by SuccToSinkTo. if (MO.isDef()) { @@ -898,7 +903,7 @@ MachineSinking::FindSuccToSinkTo(MachineInstr &MI, MachineBasicBlock *MBB, // If the physreg has no defs anywhere, it's just an ambient register // and we can freely move its uses. Alternatively, if it's allocatable, // it could get allocated to something with a def during allocation. - if (!MRI->isConstantPhysReg(Reg)) + if (!MRI->isConstantPhysReg(Reg) && !TII->isIgnorableUse(MO)) return nullptr; } else if (!MO.isDead()) { // A def that isn't dead. We can't move it. |