Reduce duplicated hash map lookups.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162362 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/StrongPHIElimination.cpp b/lib/CodeGen/StrongPHIElimination.cpp
index 5b06195..39fd600 100644
--- a/lib/CodeGen/StrongPHIElimination.cpp
+++ b/lib/CodeGen/StrongPHIElimination.cpp
@@ -404,9 +404,9 @@
 }
 
 void StrongPHIElimination::addReg(unsigned Reg) {
-  if (RegNodeMap.count(Reg))
-    return;
-  RegNodeMap[Reg] = new (Allocator) Node(Reg);
+  Node *&N = RegNodeMap[Reg];
+  if (!N)
+    N = new (Allocator) Node(Reg);
 }
 
 StrongPHIElimination::Node*
@@ -714,8 +714,9 @@
         assert(getRegColor(CopyReg) == CopyReg);
       }
 
-      if (!InsertedSrcCopyMap.count(std::make_pair(PredBB, PHIColor)))
-        InsertedSrcCopyMap[std::make_pair(PredBB, PHIColor)] = CopyInstr;
+      // Insert into map if not already there.
+      InsertedSrcCopyMap.insert(std::make_pair(std::make_pair(PredBB, PHIColor),
+                                               CopyInstr));
     }
 
     SrcMO.setReg(CopyReg);