Add alternate version of LiveVariables analysis that does not kill liveness at assignments. This 'relaxed' liveness is useful in path sensitive analysis for situations where the resulting extended liveness allows us to find some bugs.

- Added killAtAssign flag to LiveVariables
- Added relaxed LiveVariables to AnalysisContext with an accessor

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@112306 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 2 deletions

diff --git a/include/clang/Analysis/Analyses/LiveVariables.h b/include/clang/Analysis/Analyses/LiveVariables.h
index 44ab080acb..237fe14aed 100644
--- a/include/clang/Analysis/Analyses/LiveVariables.h
+++ b/include/clang/Analysis/Analyses/LiveVariables.h
@@ -41,8 +41,9 @@ struct LiveVariables_ValueTypes {
     ObserverTy* Observer;
     ValTy AlwaysLive;
     AnalysisContext *AC;
+    bool killAtAssign;
 
-    AnalysisDataTy() : Observer(NULL), AC(NULL) {}
+    AnalysisDataTy() : Observer(NULL), AC(NULL), killAtAssign(true) {}
   };
 
   //===-----------------------------------------------------===//
@@ -68,7 +69,7 @@ class LiveVariables : public DataflowValues<LiveVariables_ValueTypes,
 public:
   typedef LiveVariables_ValueTypes::ObserverTy ObserverTy;
 
-  LiveVariables(AnalysisContext &AC);
+  LiveVariables(AnalysisContext &AC, bool killAtAssign = true);
 
   /// IsLive - Return true if a variable is live at the end of a
   /// specified block.