1 files changed, 14 insertions, 1 deletions
diff --git a/include/llvm/Analysis/DivergenceAnalysis.h b/include/llvm/Analysis/DivergenceAnalysis.h
index aa2de571ba1b..328c8645d3c0 100644
--- a/include/llvm/Analysis/DivergenceAnalysis.h
+++ b/include/llvm/Analysis/DivergenceAnalysis.h
@@ -13,6 +13,8 @@
 // better decisions.
 //
 //===----------------------------------------------------------------------===//
+#ifndef LLVM_ANALYSIS_DIVERGENCE_ANALYSIS_H
+#define LLVM_ANALYSIS_DIVERGENCE_ANALYSIS_H
 
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/IR/Function.h"
@@ -35,14 +37,25 @@ public:
   // Print all divergent branches in the function.
   void print(raw_ostream &OS, const Module *) const override;
 
-  // Returns true if V is divergent.
+  // Returns true if V is divergent at its definition.
+  //
+  // Even if this function returns false, V may still be divergent when used
+  // in a different basic block.
   bool isDivergent(const Value *V) const { return DivergentValues.count(V); }
 
   // Returns true if V is uniform/non-divergent.
+  //
+  // Even if this function returns true, V may still be divergent when used
+  // in a different basic block.
   bool isUniform(const Value *V) const { return !isDivergent(V); }
 
+  // Keep the analysis results uptodate by removing an erased value.
+  void removeValue(const Value *V) { DivergentValues.erase(V); }
+
 private:
   // Stores all divergent values.
   DenseSet<const Value *> DivergentValues;
 };
 } // End llvm namespace
+
+#endif //LLVM_ANALYSIS_DIVERGENCE_ANALYSIS_H
+\ No newline at end of file