[PATCH] Add threshold for lowering lattice value 'overdefined' in LVI

[Chad Rosier]

================
Comment at: lib/Analysis/LazyValueInfo.cpp:574
@@ -556,2 +573,3 @@
   BBLV.markOverdefined();
+  LoweringOverdefinedTimes++;
   
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Please use a preincrement.

http://llvm.org/releases/2.7/docs/CodingStandards.html#micro_preincrement

http://reviews.llvm.org/D5322