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

[Joerg Sonnenberger]

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Comment at: lib/Analysis/LazyValueInfo.cpp:41
@@ -39,1 +40,3 @@
 
+// This threshold is purticularly tuned with some special cases exposing
+// regression of compile time and memory consumption.
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Typo. Maybe with the changes suggsted by Hal use just:

// Experimentally derived threshold for additional lowering lattice values per block

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Comment at: lib/Analysis/LazyValueInfo.cpp:556
@@ -542,1 +555,3 @@
+  // complexity. Therefore, we introduce OverdefinedThreshold to control
+  // the maximum times of further lowering lattice value 'overdefined'.
 
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Maybe just:

// Limit the number of additional lowering lattice value to avoid unjustified memory grows.

http://reviews.llvm.org/D5322