diff options
| -rw-r--r-- | lib/CodeGen/PostRASchedulerList.cpp | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/lib/CodeGen/PostRASchedulerList.cpp b/lib/CodeGen/PostRASchedulerList.cpp index ec56feaff9..b19525cbaa 100644 --- a/lib/CodeGen/PostRASchedulerList.cpp +++ b/lib/CodeGen/PostRASchedulerList.cpp @@ -353,6 +353,13 @@ bool SchedulePostRATDList::BreakAntiDependencies() { I != E; ++I, --Count) { MachineInstr *MI = &*I; + // After regalloc, IMPLICIT_DEF instructions aren't safe to treat as + // dependence-breaking. In the case of an INSERT_SUBREG, the IMPLICIT_DEF + // is left behind appearing to clobber the super-register, while the + // subregister needs to remain live. So we just ignore them. + if (MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF) + continue; + // Check if this instruction has an anti-dependence that we're // interested in. DenseMap<MachineInstr *, unsigned>::iterator C = CriticalAntiDeps.find(MI); |