1460     SchedDAGReverseDFS DFS;  in compute()  local
1462     DFS.follow(&SU);  in compute()
1465       while (DFS.getPred() != DFS.getPredEnd()) {  in compute()
1466         const SDep &PredDep = *DFS.getPred();  in compute()
1467         DFS.advance();  in compute()
1475           Impl.visitCrossEdge(PredDep, DFS.getCurr());  in compute()
1479         DFS.follow(PredDep.getSUnit());  in compute()
1482       const SUnit *Child = DFS.getCurr();  in compute()
1483       const SDep *PredDep = DFS.backtrack();  in compute()
1486         Impl.visitPostorderEdge(*PredDep, DFS.getCurr());  in compute()
1487       if (DFS.isComplete())  in compute()