Merge pull request #2110 from compnerd/2100-20200714

[ScheduleDAGRRList] Pacify overload mismatch in std::min.

Author: compnerd

llvm/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp

@@ -1841,7 +1841,8 @@ static SUnit *popFromQueueImpl(std::vector<SUnit *> &Q, SF &Picker) {
   unsigned BestIdx = 0;
   // Only compute the cost for the first 1000 items in the queue, to avoid
   // excessive compile-times for very large queues.
-  for (unsigned I = 1, E = std::min(Q.size(), 1000ul); I != E; I++)
+  for (unsigned I = 1, E = std::min(Q.size(), (decltype(Q.size()))1000); I != E;
+       I++)
     if (Picker(Q[BestIdx], Q[I]))
       BestIdx = I;
   SUnit *V = Q[BestIdx];