gdb/python: convert gdb.Symbol to use gdbpy_registry

This commit converts gdb.Symbol to use gdbpy_registry for lifecycle
management. Since gdb.Symbol only holds on the struct symbol * (and
prev/next links) the default invalidator can be used.

Approved-By: Tom Tromey <tom@tromey.com>

diff --git a/gdb/python/py-symbol.c b/gdb/python/py-symbol.c
index 4839d5ab4ddaf59a9cc3998c135024412362bf0c..3028a307205eb9ea70dd0c5f7fcbeda01d89b96d 100644 (file)
--- a/gdb/python/py-symbol.c
+++ b/gdb/python/py-symbol.c
@@ -29,12 +29,6 @@ struct symbol_object {
   PyObject_HEAD
   /* The GDB symbol structure this object is wrapping.  */
   struct symbol *symbol;
-  /* A symbol object is associated with an objfile, so keep track with
-     doubly-linked list, rooted in the objfile.  This lets us
-     invalidate the underlying struct symbol when the objfile is
-     deleted.  */
-  symbol_object *prev;
-  symbol_object *next;
 };
 
 /* Require a valid symbol.  All access to symbol_object->symbol should be
@@ -50,28 +44,8 @@ struct symbol_object {
       }                                                        \
   } while (0)
 
-/* A deleter that is used when an objfile is about to be freed.  */
-struct symbol_object_deleter
-{
-  void operator() (symbol_object *obj)
-  {
-    while (obj)
-      {
-       symbol_object *next = obj->next;
-
-       obj->symbol = NULL;
-       obj->next = NULL;
-       obj->prev = NULL;
-
-       obj = next;
-      }
-  }
-};
-
-static const registry<objfile>::key<symbol_object, symbol_object_deleter>
-     sympy_objfile_data_key;
-static const registry<gdbarch>::key<symbol_object, symbol_object_deleter>
-     sympy_gdbarch_data_key;
+static const gdbpy_registry<gdbpy_memoizing_registry_storage<symbol_object,
+  symbol, &symbol_object::symbol>> sympy_registry;
 
 static PyObject *
 sympy_str (PyObject *self)
@@ -349,28 +323,17 @@ static void
 set_symbol (symbol_object *obj, struct symbol *symbol)
 {
   obj->symbol = symbol;
-  obj->prev = nullptr;
   if (symbol->is_objfile_owned ())
     {
       /* Can it really happen that symbol->symtab () is NULL?  */
       if (symbol->symtab () != nullptr)
        {
-         struct objfile *objfile = symbol->objfile ();
-
-         obj->next = sympy_objfile_data_key.get (objfile);
-         if (obj->next)
-           obj->next->prev = obj;
-         sympy_objfile_data_key.set (objfile, obj);
+         sympy_registry.add (symbol->objfile (), obj);
        }
     }
   else
     {
-      struct gdbarch *arch = symbol->arch ();
-
-      obj->next = sympy_gdbarch_data_key.get (arch);
-      if (obj->next)
-       obj->next->prev = obj;
-      sympy_gdbarch_data_key.set (arch, obj);
+      sympy_registry.add (symbol->arch (), obj);
     }
 }
 
@@ -384,19 +347,11 @@ symbol_to_symbol_object (struct symbol *sym)
   /* Look if there's already a gdb.Symbol object for given SYMBOL
      and if so, return it.  */
   if (sym->is_objfile_owned ())
-    sym_obj = sympy_objfile_data_key.get (sym->objfile ());
+    sym_obj = sympy_registry.lookup (sym->objfile (), sym);
   else
-    sym_obj = sympy_gdbarch_data_key.get (sym->arch ());
-
-  while (sym_obj != nullptr)
-    {
-      if (sym_obj->symbol == sym)
-       {
-         Py_INCREF (sym_obj);
-         return (PyObject*)sym_obj;
-       }
-      sym_obj = sym_obj->next;
-    }
+    sym_obj = sympy_registry.lookup (sym->arch (), sym);
+  if (sym_obj != nullptr)
+    return (PyObject*)sym_obj;
 
   sym_obj = PyObject_New (symbol_object, &symbol_object_type);
   if (sym_obj)
@@ -419,24 +374,14 @@ sympy_dealloc (PyObject *obj)
 {
   symbol_object *sym_obj = (symbol_object *) obj;
 
-  if (sym_obj->prev)
-    sym_obj->prev->next = sym_obj->next;
-  else if (sym_obj->symbol != nullptr)
+  if (sym_obj->symbol != nullptr)
     {
       if (sym_obj->symbol->is_objfile_owned ())
-       {
-         /* Can it really happen that symbol->symtab () is NULL?  */
-         if (sym_obj->symbol->symtab () != nullptr)
-           sympy_objfile_data_key.set (sym_obj->symbol->objfile (),
-                                       sym_obj->next);
-       }
+       sympy_registry.remove (sym_obj->symbol->objfile (), sym_obj);
       else
-       sympy_gdbarch_data_key.set (sym_obj->symbol->arch (),
-                                   sym_obj->next);
+       sympy_registry.remove (sym_obj->symbol->arch (), sym_obj);
     }
-  if (sym_obj->next)
-    sym_obj->next->prev = sym_obj->prev;
-  sym_obj->symbol = NULL;
+
   Py_TYPE (obj)->tp_free (obj);
 }