Index: lib/Target/AMDGPU/SIMachineScheduler.cpp
===================================================================
--- lib/Target/AMDGPU/SIMachineScheduler.cpp
+++ lib/Target/AMDGPU/SIMachineScheduler.cpp
@@ -974,12 +974,7 @@
   for (unsigned SUNum : DAG->BottomUpIndex2SU) {
     SUnit *SU = &DAG->SUnits[SUNum];
     unsigned color = CurrentColoring[SU->NodeNum];
-    std::map<unsigned, unsigned>::iterator Pos = ColorCount.find(color);
-      if (Pos != ColorCount.end()) {
-        ++ColorCount[color];
-      } else {
-        ColorCount[color] = 1;
-      }
+     ++ColorCount[color];
   }
 
   for (unsigned SUNum : DAG->BottomUpIndex2SU) {
@@ -1331,13 +1326,7 @@
         continue;
 
       int PredID = BlocksStruct.TopDownIndex2Block[topoInd];
-      std::map<unsigned, unsigned>::iterator RegPos =
-        LiveOutRegsNumUsages[PredID].find(Reg);
-      if (RegPos != LiveOutRegsNumUsages[PredID].end()) {
-        ++LiveOutRegsNumUsages[PredID][Reg];
-      } else {
-        LiveOutRegsNumUsages[PredID][Reg] = 1;
-      }
+      ++LiveOutRegsNumUsages[PredID][Reg];
     }
   }
 
@@ -1377,12 +1366,8 @@
         }
       }
 
-      if (!Found) {
-        if (LiveRegsConsumers.find(Reg) == LiveRegsConsumers.end())
-          LiveRegsConsumers[Reg] = 1;
-        else
-          ++LiveRegsConsumers[Reg];
-      }
+      if (!Found)
+        ++LiveRegsConsumers[Reg];
     }
   }
 
@@ -1578,12 +1563,10 @@
        LiveOutRegsNumUsages[Block->getID()].begin(),
        E = LiveOutRegsNumUsages[Block->getID()].end(); RegI != E; ++RegI) {
     std::pair<unsigned, unsigned> RegP = *RegI;
-    if (LiveRegsConsumers.find(RegP.first) == LiveRegsConsumers.end())
-      LiveRegsConsumers[RegP.first] = RegP.second;
-    else {
-      assert(LiveRegsConsumers[RegP.first] == 0);
-      LiveRegsConsumers[RegP.first] += RegP.second;
-    }
+    // We produce this register, thus it must not be previously alive.
+    assert(LiveRegsConsumers.find(RegP.first) == LiveRegsConsumers.end() ||
+           LiveRegsConsumers[RegP.first] == 0);
+    LiveRegsConsumers[RegP.first] += RegP.second;
   }
   if (LastPosHighLatencyParentScheduled[Block->getID()] >
         (unsigned)LastPosWaitedHighLatency)