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/Analysis/LazyValueInfo.cpp b/lib/Analysis/LazyValueInfo.cpp
index 9140786..c2306b4 100644
--- a/lib/Analysis/LazyValueInfo.cpp
+++ b/lib/Analysis/LazyValueInfo.cpp
@@ -470,8 +470,10 @@
     return true;
 
   LVIValueHandle ValHandle(Val, this);
-  if (!ValueCache.count(ValHandle)) return false;
-  return ValueCache[ValHandle].count(BB);
+  std::map<LVIValueHandle, ValueCacheEntryTy>::iterator I =
+    ValueCache.find(ValHandle);
+  if (I == ValueCache.end()) return false;
+  return I->second.count(BB);
 }
 
 LVILatticeVal LazyValueInfoCache::getBlockValue(Value *Val, BasicBlock *BB) {