Index: lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
+++ lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
@@ -745,7 +745,7 @@
                   SmallVectorImpl<std::pair<unsigned, MachineInstr*> > &Orders,
                   SmallSet<unsigned, 8> &Seen) {
   unsigned Order = N->getIROrder();
-  if (!Order || !Seen.insert(Order).second) {
+  if (!Order || Seen.count(Order) != 0) {
     // Process any valid SDDbgValues even if node does not have any order
     // assigned.
     ProcessSDDbgValues(N, DAG, Emitter, Orders, VRBaseMap, 0);
@@ -759,10 +759,11 @@
       // BB->back().isPHI() test will not fire when we want it to.
       std::prev(IP)->isPHI()) {
     // Did not insert any instruction.
-    Orders.push_back({Order, (MachineInstr *)nullptr});
+    //Orders.push_back({Order, (MachineInstr *)nullptr});
     return;
   }
 
+  Seen.insert(Order);
   Orders.push_back({Order, &*std::prev(IP)});
   ProcessSDDbgValues(N, DAG, Emitter, Orders, VRBaseMap, Order);
 }
Index: test/DebugInfo/X86/sdag-dbgvalue-phi-use-2.ll
===================================================================
--- test/DebugInfo/X86/sdag-dbgvalue-phi-use-2.ll
+++ test/DebugInfo/X86/sdag-dbgvalue-phi-use-2.ll
@@ -44,14 +44,17 @@
 ; CHECK-NEXT: [[REG4:%[0-9]+]]:gr32 = PHI
 ; CHECK-NEXT: DBG_VALUE [[REG3]], $noreg, !16
 ; CHECK-NEXT: DBG_VALUE 555, $noreg, !17
-; XXX: Shouldn't the following DBG_VALUE be placed after the add (ADD32rr).
+; CHECK-NEXT: [[ADDREG:%[0-9]+]]:gr32 = nuw nsw ADD32rr
 ; CHECK-NEXT: DBG_VALUE [[REG2]], $noreg, !17
-; CHECK-NEXT: ADD32rr
-; XXX: Shouldn't the following DBG_VALUE be placed after the mul (LEA etc).
+; CHECK:      [[MULREG:%[0-9]+]]:gr32 = LEA64_32r
 ; CHECK-NEXT: DBG_VALUE 777, $noreg, !17
-; CHECK:      INC32r
+; XXX: The following DBG_VALUE should have stayed below the INC32r
+; CHECK-NEXT: DBG_VALUE [[MULREG]], $noreg, !16
+; CHECK-NEXT: [[INCREG:%[0-9]+]]:gr32 = nuw nsw INC32r
+; CHECK-NEXT: DBG_VALUE [[ADDREG]], $noreg, !15
+; CHECK-NEXT: DBG_VALUE [[INCREG]], $noreg, !17
 ; XXX: Shouldn't the following DBG_VALUE be placed after the icmp (the non-dead implicit def of $eflags)
-; CHECK:      DBG_VALUE [[REG4]]
+; CHECK-NEXT: DBG_VALUE [[REG4]]
 ; CHECK-NEXT: implicit-def $eflags
   %u.023 = phi i32 [ 0, %for.body.lr.ph ], [ %inc, %for.body ]
   %y.022 = phi i32 [ 13, %for.body.lr.ph ], [ %mul, %for.body ]