156   BlockInterference *BI = &Blocks[MBBNum];  in update()  local
160     BI->Tag = Tag;  in update()
161     BI->First = BI->Last = SlotIndex();  in update()
171       if (!BI->First.isValid() || StartI < BI->First)  in update()
172         BI->First = StartI;  in update()
184       if (!BI->First.isValid() || StartI < BI->First)  in update()
185         BI->First = StartI;  in update()
191     SlotIndex Limit = BI->First.isValid() ? BI->First : Stop;  in update()
196         BI->First = RegMaskSlots[i];  in update()
201     if (BI->First.isValid())  in update()
208     BI = &Blocks[MBBNum];  in update()
209     if (BI->Tag == Tag)  in update()
224     if (!BI->Last.isValid() || StopI > BI->Last)  in update()
225       BI->Last = StopI;  in update()
241     if (!BI->Last.isValid() || StopI > BI->Last)  in update()
242       BI->Last = StopI;  in update()
248   SlotIndex Limit = BI->Last.isValid() ? BI->Last : Start;  in update()
254       BI->Last = RegMaskSlots[i-1].getDeadSlot();  in update()