Corrected code in base class and removed duplicate code

Author: thk123

src/analyses/ai.cpp

@@ -57,29 +57,31 @@ bool ai_domain_baset::ai_simplify_lhs(
   if(condition.id()==ID_index)
   {
     index_exprt ie=to_index_expr(condition);
-    bool changed=ai_simplify(ie.index(), ns);
-    if(changed)
+    bool no_simplification=ai_simplify(ie.index(), ns);
+    if(!no_simplification)
       condition=simplify_expr(ie, ns);
 
-    return !changed;
+    return no_simplification;
   }
   else if(condition.id()==ID_dereference)
   {
     dereference_exprt de=to_dereference_expr(condition);
-    bool changed=ai_simplify(de.pointer(), ns);
-    if(changed)
+    bool no_simplification=ai_simplify(de.pointer(), ns);
+    if(!no_simplification)
       condition=simplify_expr(de, ns);  // So *(&x) -> x
 
-    return !changed;
+    return no_simplification;
   }
   else if(condition.id()==ID_member)
   {
     member_exprt me=to_member_expr(condition);
-    bool changed=ai_simplify_lhs(me.compound(), ns); // <-- lhs!
-    if(changed)
+    // Carry on the RHS since we still require an addressable object for the
+    // struct
+    bool no_simplification=ai_simplify_lhs(me.compound(), ns);
+    if(!no_simplification)
       condition=simplify_expr(me, ns);
 
-    return !changed;
+    return no_simplification;
   }
   else
     return true;

src/analyses/variable-sensitivity/variable_sensitivity_domain.cpp

@@ -350,73 +350,6 @@ bool variable_sensitivity_domaint::is_top() const
 
 /*******************************************************************\
 
-Function: variable_sensitivity_domaint::ai_simplify_lhs
-
-  Inputs:
-   condition - the expression to simplify
-   ns - the namespace
-
- Outputs: True if condition did not change. False otherwise. condition
-          will be updated with the simplified condition if it has worked
-
- Purpose: Use the information in the domain to simplify the expression
-          on the LHS of an assignment. This for example won't simplify symbols
-          to their values, but does simplify indices in arrays, members of
-          structs and dereferencing of pointers
-
-\*******************************************************************/
-
-bool variable_sensitivity_domaint::ai_simplify_lhs(
-  exprt &condition, const namespacet &ns) const
-{
-  // Care must be taken here to give something that is still writable
-  if(condition.id()==ID_index)
-  {
-    index_exprt ie = to_index_expr(condition);
-    exprt index = ie.index();
-    bool no_simplification=ai_simplify(index, ns);
-    if(!no_simplification)
-    {
-      ie.index() = index;
-      condition = simplify_expr(ie, ns);
-    }
-
-    return no_simplification;
-  }
-  else if(condition.id()==ID_dereference)
-  {
-    dereference_exprt de = to_dereference_expr(condition);
-    exprt pointer = de.pointer();
-    bool no_simplification = ai_simplify(pointer, ns);
-    if(!no_simplification)
-    {
-      de.pointer() = pointer;
-      condition = simplify_expr(de, ns);  // So *(&x) -> x
-    }
-
-    return no_simplification;
-  }
-  else if(condition.id()==ID_member)
-  {
-    member_exprt me = to_member_expr(condition);
-    exprt compound = me.compound();
-    // Carry on the RHS since we still require an addressable object for the
-    // struct
-    bool no_simplification = ai_simplify_lhs(compound, ns);
-    if(!no_simplification)
-    {
-      me.compound() = compound;
-      condition = simplify_expr(me, ns);
-    }
-
-    return no_simplification;
-  }
-  else
-    return true;
-}
-
-/*******************************************************************\
-
 Function: variable_sensitivity_domaint::transform_function_call
 
   Inputs:

src/analyses/variable-sensitivity/variable_sensitivity_domain.h

@@ -104,10 +104,6 @@ class variable_sensitivity_domaint:public ai_domain_baset
   bool is_bottom() const override;
   bool is_top() const override;
 
-  bool ai_simplify_lhs(
-    exprt &condition,
-    const namespacet &ns) const override;
-
 private:
   void transform_function_call(
     locationt from,