1463     SchedDAGReverseDFS DFS;  in compute()  local
1465     DFS.follow(&SU);  in compute()
1468       while (DFS.getPred() != DFS.getPredEnd()) {  in compute()
1469         const SDep &PredDep = *DFS.getPred();  in compute()
1470         DFS.advance();  in compute()
1478           Impl.visitCrossEdge(PredDep, DFS.getCurr());  in compute()
1482         DFS.follow(PredDep.getSUnit());  in compute()
1485       const SUnit *Child = DFS.getCurr();  in compute()
1486       const SDep *PredDep = DFS.backtrack();  in compute()
1489         Impl.visitPostorderEdge(*PredDep, DFS.getCurr());  in compute()
1490       if (DFS.isComplete())  in compute()