Identify Analysis pass.

Do not run analysis pass again if analysis info is still available.
This fixes PR1441.

llvm-svn: 48476

1 files changed, 3 insertions, 0 deletions

diff --git a/llvm/lib/Analysis/AliasAnalysisEvaluator.cpp b/llvm/lib/Analysis/AliasAnalysisEvaluator.cpp
index 1ed06805fa6..51fdec49432 100644
--- a/llvm/lib/Analysis/AliasAnalysisEvaluator.cpp
+++ b/llvm/lib/Analysis/AliasAnalysisEvaluator.cpp
@@ -70,6 +70,9 @@ namespace {
       return false;
     }
 
+    /// isAnalysis - Return true if this pass is  implementing an analysis pass.
+    virtual bool isAnalysis() const { return true; }
+
     bool runOnFunction(Function &F);
     bool doFinalization(Module &M);
   };