Index: llvm/lib/CodeGen/MachineScheduler.cpp
===================================================================
--- llvm/lib/CodeGen/MachineScheduler.cpp
+++ llvm/lib/CodeGen/MachineScheduler.cpp
@@ -2969,6 +2969,33 @@
     return;
 
   if (SameBoundary) {
+    // Choose in priority instructions with lower latencies.
+    if (Zone->isTop()) {
+      // Top-down scheduling.
+      unsigned TryDepth = TryCand.SU->getDepth();
+      unsigned Depth = Cand.SU->getDepth();
+
+      // Prefer lowest depth.
+      if (TryDepth > Depth)
+        return;
+
+      // For equal depth, prefer higher height.
+      if (TryDepth == Depth && TryCand.SU->getHeight() < Cand.SU->getHeight())
+        return;
+    } else {
+      // Bottom-up scheduling.
+      unsigned TryHeight = TryCand.SU->getHeight();
+      unsigned Height = Cand.SU->getHeight();
+
+      // Prefer lowest height.
+      if (TryHeight > Height)
+        return;
+
+      // For equal height, prefer higher depth.
+      if (TryHeight == Height && TryCand.SU->getDepth() < Cand.SU->getDepth())
+        return;
+    }
+
     // Avoid critical resource consumption and balance the schedule.
     TryCand.initResourceDelta(DAG, SchedModel);
     if (tryLess(TryCand.ResDelta.CritResources, Cand.ResDelta.CritResources,
@@ -3273,6 +3300,10 @@
                  TryCand, Cand, Cluster))
     return;
 
+  // Choose in priority instructions with lower latencies.
+  if (TryCand.SU->getDepth() > Cand.SU->getDepth())
+    return;
+
   // Avoid critical resource consumption and balance the schedule.
   if (tryLess(TryCand.ResDelta.CritResources, Cand.ResDelta.CritResources,
               TryCand, Cand, ResourceReduce))