Auxiliary function to check if the ssa has enough data to build an id…

…entifier

src/util/ssa_expr.cpp

@@ -78,6 +78,19 @@ static void build_ssa_identifier_rec(
     assert(false);
 }
 
+/* Used to determine whether or not an identifier can be built
+   * before trying and getting an exception */
+bool ssa_exprt::can_build_identifier(const exprt &expr)
+{
+  if(expr.id()==ID_symbol)
+    return true;
+  else if(expr.id()==ID_member ||
+          expr.id()==ID_index)
+    return can_build_identifier(expr.op0());
+  else
+    return false;
+}
+
 /*******************************************************************\
 
 Function: ssa_exprt::build_identifier

src/util/ssa_expr.h

@@ -64,7 +64,7 @@ class ssa_exprt:public symbol_exprt
 
   const irep_idt get_l1_object_identifier() const
   {
-    #if 0
+    #if 1
     return get_l1_object().get_identifier();
     #else
     // the above is the clean version, this is the fast one, using
@@ -134,6 +134,10 @@ class ssa_exprt:public symbol_exprt
     const irep_idt &l0,
     const irep_idt &l1,
     const irep_idt &l2);
+
+  /* Used to determine whether or not an identifier can be built
+   * before trying and getting an exception */
+  static bool can_build_identifier(const exprt &src);
 };
 
 /*! \brief Cast a generic exprt to an \ref ssa_exprt