Add ExplodedNode utility methods 'getLocationAs()' and 'getFirstPred()'


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71699 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Analysis/PathSensitive/ExplodedGraph.h b/include/clang/Analysis/PathSensitive/ExplodedGraph.h
index f00e488..8494d93 100644
--- a/include/clang/Analysis/PathSensitive/ExplodedGraph.h
+++ b/include/clang/Analysis/PathSensitive/ExplodedGraph.h
@@ -123,6 +123,9 @@
   /// getLocation - Returns the edge associated with the given node.
   ProgramPoint getLocation() const { return Location; }
   
+  template <typename T>
+  const T* getLocationAs() const { return llvm::dyn_cast<T>(&Location); }
+  
   unsigned succ_size() const { return Succs.size(); }
   unsigned pred_size() const { return Preds.size(); }
   bool succ_empty() const { return Succs.empty(); }
@@ -183,6 +186,14 @@
     ExplodedNodeImpl::addPredecessor(V);
   }
   
+  ExplodedNode* getFirstPred() {
+    return pred_empty() ? NULL : *(pred_begin());
+  }
+  
+  const ExplodedNode* getFirstPred() const {
+    return const_cast<ExplodedNode*>(this)->getFirstPred();
+  }
+  
   // Iterators over successor and predecessor vertices.
   typedef ExplodedNode**       succ_iterator;
   typedef const ExplodedNode* const * const_succ_iterator;