Static Analyzer: Add a convinience API. Add comment.

llvm-svn: 137000

clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h

@@ -90,6 +90,10 @@ public:
     return Eng.getSValBuilder();
   }
 
+  SymbolManager &getSymbolManager() {
+    return getSValBuilder().getSymbolManager();
+  }
+
   ExplodedNode *generateNode(bool autoTransition = true) {
     assert(statement && "Only transitions with statements currently supported");
     ExplodedNode *N = generateNodeImpl(statement, getState(), false,

clang/include/clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h

@@ -389,6 +389,9 @@ public:
 
   const SymbolExtent *getExtentSymbol(const SubRegion *R);
 
+  /// Creates a metadata symbol associated with a specific region.
+  /// VisitCount can be used to differentiate regions corresponding to
+  /// different loop iterations, thus, making the symbol path-dependent.
   const SymbolMetadata* getMetadataSymbol(const MemRegion* R, const Stmt* S,
                                           QualType T, unsigned VisitCount,
                                           const void* SymbolTag = 0);