+ bool DeadDef = false;
+ if (RequireIntervals) {
+ const LiveRange *LR = getLiveRange(Reg);
+ if (LR) {
+ LiveQueryResult LRQ = LR->Query(SlotIdx);
+ DeadDef = LRQ.isDeadDef();
+ }
+ }
+ if (DeadDef) {
+ // LiveIntervals knows this is a dead even though it's MachineOperand is
+ // not flagged as such. Since this register will not be recorded as
+ // live-out, increase its PDiff value to avoid underflowing pressure.
+ if (PDiff)
+ PDiff->addPressureChange(Reg, false, MRI);
+ } else {
+ if (LiveRegs.erase(Reg))
+ decreaseRegPressure(Reg);
+ else
+ discoverLiveOut(Reg);
+ }