Daily bump.
[official-gcc.git] / gcc / vtable-verify.h
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1 /* Copyright (C) 2013-2014 Free Software Foundation, Inc.
3 This file is part of GCC.
5 GCC is free software; you can redistribute it and/or modify it under
6 the terms of the GNU General Public License as published by the Free
7 Software Foundation; either version 3, or (at your option) any later
8 version.
10 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
11 WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 for more details.
15 You should have received a copy of the GNU General Public License
16 along with GCC; see the file COPYING3. If not see
17 <http://www.gnu.org/licenses/>. */
19 /* Virtual Table Pointer Security. */
21 #ifndef VTABLE_VERIFY_H
22 #define VTABLE_VERIFY_H
24 #include "sbitmap.h"
25 #include "hash-table.h"
27 /* The function decl used to create calls to __VLTVtableVerify. It must
28 be global because it needs to be initialized in the C++ front end, but
29 used in the middle end (in the vtable verification pass). */
31 extern tree verify_vtbl_ptr_fndecl;
33 /* Global variable keeping track of how many vtable map variables we
34 have created. */
35 extern unsigned num_vtable_map_nodes;
37 /* Keep track of how many virtual calls we are actually verifying. */
38 extern int total_num_virtual_calls;
39 extern int total_num_verified_vcalls;
41 /* Each vtable map variable corresponds to a virtual class. Each
42 vtable map variable has a hash table associated with it, that keeps
43 track of the vtable pointers for which we have generated a call to
44 __VLTRegisterPair (with the current vtable map variable). This is
45 the hash table node that is used for each entry in this hash table
46 of vtable pointers.
48 Sometimes there are multiple valid vtable pointer entries that use
49 the same vtable pointer decl with different offsets. Therefore,
50 for each vtable pointer in the hash table, there is also an array
51 of offsets used with that vtable. */
53 struct vtable_registration
55 tree vtable_decl; /* The var decl of the vtable. */
56 vec<unsigned> offsets; /* The offsets array. */
59 struct registration_hasher : typed_noop_remove <struct vtable_registration>
61 typedef struct vtable_registration value_type;
62 typedef struct vtable_registration compare_type;
63 static inline hashval_t hash (const value_type *);
64 static inline bool equal (const value_type *, const compare_type *);
67 typedef hash_table<registration_hasher> register_table_type;
68 typedef register_table_type::iterator registration_iterator_type;
70 /* This struct is used to represent the class hierarchy information
71 that we need. Each vtable map variable has an associated class
72 hierarchy node (struct vtv_graph_node). Note: In this struct,
73 'children' means immediate descendants in the class hierarchy;
74 'descendant' means any descendant however many levels deep. */
76 struct vtv_graph_node {
77 tree class_type; /* The record_type of the class. */
78 unsigned class_uid; /* A unique, monotonically
79 ascending id for class node.
80 Each vtable map node also has
81 an id. The class uid is the
82 same as the vtable map node id
83 for nodes corresponding to the
84 same class. */
85 unsigned num_processed_children; /* # of children for whom we have
86 computed the class hierarchy
87 transitive closure. */
88 vec<struct vtv_graph_node *> parents; /* Vector of parents in the graph. */
89 vec<struct vtv_graph_node *> children; /* Vector of children in the graph.*/
90 sbitmap descendants; /* Bitmap representing all this node's
91 descendants in the graph. */
94 /* This is the node used for our hashtable of vtable map variable
95 information. When we create a vtable map variable (var decl) we
96 put it into one of these nodes; create a corresponding
97 vtv_graph_node for our class hierarchy info and store that in this
98 node; generate a unique (monotonically ascending) id for both the
99 vtbl_map_node and the vtv_graph_node; and insert the node into two
100 data structures (to make it easy to find in several different
101 ways): 1). A hash table ("vtbl_map_hash" in vtable-verify.c).
102 This gives us an easy way to check to see if we already have a node
103 for the vtable map variable or not; and 2). An array (vector) of
104 vtbl_map_nodes, where the array index corresponds to the unique id
105 of the vtbl_map_node, which gives us an easy way to use bitmaps to
106 represent and find the vtable map nodes. */
108 struct vtbl_map_node {
109 tree vtbl_map_decl; /* The var decl for the vtable map
110 variable. */
111 tree class_name; /* The DECL_ASSEMBLER_NAME of the
112 class. */
113 struct vtv_graph_node *class_info; /* Our class hierarchy info for the
114 class. */
115 unsigned uid; /* The unique id for the vtable map
116 variable. */
117 struct vtbl_map_node *next, *prev; /* Pointers for the linked list
118 structure. */
119 register_table_type *registered; /* Hashtable of vtable pointers for which
120 we have generated a _VLTRegisterPair
121 call with this vtable map variable. */
122 bool is_used; /* Boolean indicating if we used this vtable map
123 variable in a call to __VLTVerifyVtablePointer. */
126 /* Controls debugging for vtable verification. */
127 extern bool vtv_debug;
129 /* The global vector of vtbl_map_nodes. */
130 extern vec<struct vtbl_map_node *> vtbl_map_nodes_vec;
132 extern struct vtbl_map_node *vtbl_map_get_node (tree);
133 extern struct vtbl_map_node *find_or_create_vtbl_map_node (tree);
134 extern void vtbl_map_node_class_insert (struct vtbl_map_node *, unsigned);
135 extern bool vtbl_map_node_registration_find (struct vtbl_map_node *,
136 tree, unsigned);
137 extern bool vtbl_map_node_registration_insert (struct vtbl_map_node *,
138 tree, unsigned);
140 #endif /* VTABLE_VERIFY_H */