Add merge_location parameter to abstract_environment::merge

Author: jezhiggins

src/analyses/variable-sensitivity/abstract_environment.cpp

@@ -345,6 +345,7 @@ abstract_object_pointert abstract_environmentt::add_object_context(
 
 bool abstract_environmentt::merge(
   const abstract_environmentt &env,
+  const goto_programt::const_targett &merge_location,
   widen_modet widen_mode)
 {
   // for each entry in the incoming environment we need to either add it

src/analyses/variable-sensitivity/abstract_environment.h

@@ -190,10 +190,14 @@ class abstract_environmentt
   /// Computes the join between "this" and "b"
   ///
   /// \param env: the other environment
+  /// \param merge_location: when the merge is happening
   /// \param widen_mode: indicates if this is a widening merge
   ///
   /// \return A Boolean, true when the merge has changed something
-  virtual bool merge(const abstract_environmentt &env, widen_modet widen_mode);
+  virtual bool merge(
+    const abstract_environmentt &env,
+    const goto_programt::const_targett &merge_location,
+    widen_modet widen_mode);
 
   /// This should be used as a default case / everything else has failed
   /// The string is so that I can easily find and diagnose cases where this

src/analyses/variable-sensitivity/variable_sensitivity_domain.cpp

@@ -232,7 +232,8 @@ bool variable_sensitivity_domaint::merge(
   auto widen_mode =
     from->should_widen(*to) ? widen_modet::could_widen : widen_modet::no;
   // Use the abstract_environment merge
-  bool any_changes = abstract_state.merge(b.abstract_state, widen_mode);
+  bool any_changes =
+    abstract_state.merge(b.abstract_state, to->current_location(), widen_mode);
 
   DATA_INVARIANT(abstract_state.verify(), "Structural invariant");
   return any_changes;