Remove virtuals style improvements

No functional changes intended

Author: smowton

src/goto-programs/class_identifier.cpp

@@ -9,6 +9,7 @@ Author: Chris Smowton, [email protected]
 #include "class_identifier.h"
 
 #include <util/std_expr.h>
+#include <util/namespace.h>
 
 /*******************************************************************\
 
@@ -33,25 +34,24 @@ static exprt build_class_identifier(
   while(1)
   {
     const typet &type=ns.follow(e.type());
-    assert(type.id()==ID_struct);
-
     const struct_typet &struct_type=to_struct_type(type);
     const struct_typet::componentst &components=struct_type.components();
     assert(!components.empty());
 
+    const auto &first_member_name=components.front().get_name();
     member_exprt member_expr(
       e,
-      components.front().get_name(),
+      first_member_name,
       components.front().type());
 
-    if(components.front().get_name()=="@class_identifier")
+    if(first_member_name=="@class_identifier")
     {
       // found it
       return member_expr;
     }
     else
     {
-      e=member_expr;
+      e.swap(member_expr);
     }
   }
 }
@@ -70,17 +70,18 @@ Function: get_class_identifier_field
 \*******************************************************************/
 
 exprt get_class_identifier_field(
-  exprt this_expr,
+  const exprt &this_expr_in,
   const symbol_typet &suggested_type,
   const namespacet &ns)
 {
   // Get a pointer from which we can extract a clsid.
   // If it's already a pointer to an object of some sort, just use it;
   // if it's void* then use the suggested type.
 
+  exprt this_expr=this_expr_in;
   assert(this_expr.type().id()==ID_pointer &&
          "Non-pointer this-arg in remove-virtuals?");
-  const auto& points_to=this_expr.type().subtype();
+  const auto &points_to=this_expr.type().subtype();
   if(points_to==empty_typet())
     this_expr=typecast_exprt(this_expr, pointer_typet(suggested_type));
   exprt deref=dereference_exprt(this_expr, this_expr.type().subtype());

src/goto-programs/class_identifier.h

@@ -9,12 +9,12 @@ Author: Chris Smowton, [email protected]
 #ifndef CPROVER_GOTO_PROGRAMS_CLASS_IDENTIFIER_H
 #define CPROVER_GOTO_PROGRAMS_CLASS_IDENTIFIER_H
 
-#include <util/expr.h>
-#include <util/std_types.h>
-#include <util/namespace.h>
+class exprt;
+class namespacet;
+class symbol_typet;
 
 exprt get_class_identifier_field(
-  exprt this_expr,
+  const exprt &this_expr,
   const symbol_typet &suggested_type,
   const namespacet &ns);
 

src/goto-programs/remove_virtual_functions.cpp

@@ -139,9 +139,9 @@ void remove_virtual_functionst::remove_virtual_function(
   goto_programt new_code_gotos;
 
   exprt this_expr=code.arguments()[0];
-  // If necessary, cast to the last candidate function to get the object's clsid.
-  // By the structure of get_functions, this is the parent of all other classes
-  // under consideration.
+  // If necessary, cast to the last candidate function to
+  // get the object's clsid. By the structure of get_functions,
+  // this is the parent of all other classes under consideration.
   symbol_typet suggested_type(functions.back().class_id);
   exprt c_id2=get_class_identifier_field(this_expr, suggested_type, ns);
 
@@ -196,8 +196,10 @@ void remove_virtual_functionst::remove_virtual_function(
     const irep_idt comment=it->source_location.get_comment();
     it->source_location=target->source_location;
     it->function=target->function;
-    if(!property_class.empty()) it->source_location.set_property_class(property_class);
-    if(!comment.empty()) it->source_location.set_comment(comment);
+    if(!property_class.empty())
+      it->source_location.set_property_class(property_class);
+    if(!comment.empty())
+      it->source_location.set_comment(comment);
   }
 
   goto_programt::targett next_target=target;
@@ -302,7 +304,8 @@ void remove_virtual_functionst::get_functions(
     const class_hierarchyt::idst &parents=
       class_hierarchy.class_map[c].parents;
 
-    if(parents.empty()) break;
+    if(parents.empty())
+      break;
     c=parents.front();
   }
 
@@ -380,7 +383,6 @@ bool remove_virtual_functionst::remove_virtual_functions(
 
   if(did_something)
   {
-    //remove_skip(goto_program);
     goto_program.update();
   }