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

[hfinkel at anl.gov]

I'd really prefer that we keep this count per block, instead of a global count. Is that possible?

Also, please upload full-context diffs in the future (see: http://llvm.org/docs/Phabricator.html).

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Comment at: lib/Analysis/LazyValueInfo.cpp:360
@@ -351,1 +359,3 @@
+    /// lowered.
+    unsigned LoweringOverdefinedTimes;
     
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Could you make this a DenseMap<BasicBlock *, unsigned>, and keep a count per block?

http://reviews.llvm.org/D5322