[gdb/DWARF] Introduce linked list for dynamic attributes

This patch introduces a linked list for dynamic attributes of a type.
This is a pre-work for the Fortran dynamic array support. The Fortran
dynamic array support will add more dynamic attributes to a type.
As only a few types will have such dynamic attributes set, a linked
list is more efficient in terms of memory consumption than adding
multiple attributes to main_type.

gdb/ChangeLog:

        * gdbtypes.c (resolve_dynamic_type_internal): Adapt
        data_location usage to linked list.
        (resolve_dynamic_type_internal): Adapt data_location to
        linked list.
        (get_dyn_prop, add_dyn_prop, copy_dynamic_prop_list): New function.
        (copy_type_recursive, copy_type): Add copy of linked list.
        * gdbtypes.h (enum dynamic_prop_node_kind): New enum.
        (struct dynamic_prop_list): New struct.
        * dwarf2read.c (set_die_type): Set data_location data.

1 files changed, 49 insertions, 6 deletions

diff --git a/gdb/gdbtypes.h b/gdb/gdbtypes.h
index 2c5ccf4272..79d72dfeef 100644
--- a/gdb/gdbtypes.h
+++ b/gdb/gdbtypes.h
@@ -434,6 +434,26 @@ struct dynamic_prop
   union dynamic_prop_data data;
 };
 
+/* * Define a type's dynamic property node kind.  */
+enum dynamic_prop_node_kind
+{
+  /* A property providing a type's data location.
+     Evaluating this field yields to the location of an object's data.  */
+  DYN_ATTR_DATA_LOCATION,
+};
+
+/* * List for dynamic type attributes.  */
+struct dynamic_prop_list
+{
+  /* The kind of dynamic prop in this node.  */
+  enum dynamic_prop_node_kind prop_kind;
+
+  /* The dynamic property itself.  */
+  struct dynamic_prop *prop;
+
+  /* A pointer to the next dynamic property.  */
+  struct dynamic_prop_list *next;
+};
 
 /* * Determine which field of the union main_type.fields[x].loc is
    used.  */
@@ -719,10 +739,8 @@ struct main_type
 
   union type_specific type_specific;
 
-  /* * Contains a location description value for the current type. Evaluating
-     this field yields to the location of the data for an object.  */
-
-  struct dynamic_prop *data_location;
+  /* * Contains all dynamic type properties.  */
+  struct dynamic_prop_list *dyn_prop_list;
 };
 
 /* * A ``struct type'' describes a particular instance of a type, with
@@ -1238,9 +1256,9 @@ extern void allocate_gnat_aux_type (struct type *);
 #define TYPE_LOW_BOUND_KIND(range_type) \
   TYPE_RANGE_DATA(range_type)->low.kind
 
-/* Attribute accessors for the type data location.  */
+/* Property accessors for the type data location.  */
 #define TYPE_DATA_LOCATION(thistype) \
-  TYPE_MAIN_TYPE(thistype)->data_location
+  get_dyn_prop (DYN_ATTR_DATA_LOCATION, thistype)
 #define TYPE_DATA_LOCATION_BATON(thistype) \
   TYPE_DATA_LOCATION (thistype)->data.baton
 #define TYPE_DATA_LOCATION_ADDR(thistype) \
@@ -1248,6 +1266,17 @@ extern void allocate_gnat_aux_type (struct type *);
 #define TYPE_DATA_LOCATION_KIND(thistype) \
   TYPE_DATA_LOCATION (thistype)->kind
 
+/* Attribute accessors for dynamic properties.  */
+#define TYPE_DYN_PROP_LIST(thistype) \
+  TYPE_MAIN_TYPE(thistype)->dyn_prop_list
+#define TYPE_DYN_PROP_BATON(dynprop) \
+  dynprop->data.baton
+#define TYPE_DYN_PROP_ADDR(dynprop) \
+  dynprop->data.const_val
+#define TYPE_DYN_PROP_KIND(dynprop) \
+  dynprop->kind
+
+
 /* Moto-specific stuff for FORTRAN arrays.  */
 
 #define TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED(arraytype) \
@@ -1767,6 +1796,20 @@ extern struct type *resolve_dynamic_type (struct type *type, CORE_ADDR addr);
 /* * Predicate if the type has dynamic values, which are not resolved yet.  */
 extern int is_dynamic_type (struct type *type);
 
+/* * Return the dynamic property of the requested KIND from TYPE's
+   list of dynamic properties.  */
+extern struct dynamic_prop *get_dyn_prop
+  (enum dynamic_prop_node_kind kind, const struct type *type);
+
+/* * Given a dynamic property PROP of a given KIND, add this dynamic
+   property to the given TYPE.
+
+   This function assumes that TYPE is objfile-owned, and that OBJFILE
+   is the TYPE's objfile.  */
+extern void add_dyn_prop
+  (enum dynamic_prop_node_kind kind, struct dynamic_prop prop,
+   struct type *type, struct objfile *objfile);
+
 extern struct type *check_typedef (struct type *);
 
 #define CHECK_TYPEDEF(TYPE)			\