Implement protection of stack variables
[gcc.git] / gcc / asan.h
1 /* AddressSanitizer, a fast memory error detector.
2 Copyright (C) 2011, 2012 Free Software Foundation, Inc.
3 Contributed by Kostya Serebryany <kcc@google.com>
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
11
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
20
21 #ifndef TREE_ASAN
22 #define TREE_ASAN
23
24 extern void asan_finish_file (void);
25 extern rtx asan_emit_stack_protection (rtx, HOST_WIDE_INT *, tree *, int);
26
27 /* Alias set for accessing the shadow memory. */
28 extern alias_set_type asan_shadow_set;
29
30 /* Shadow memory is found at
31 (address >> ASAN_SHADOW_SHIFT) + targetm.asan_shadow_offset (). */
32 #define ASAN_SHADOW_SHIFT 3
33
34 /* Red zone size, stack and global variables are padded by ASAN_RED_ZONE_SIZE
35 up to 2 * ASAN_RED_ZONE_SIZE - 1 bytes. */
36 #define ASAN_RED_ZONE_SIZE 32
37
38 /* Shadow memory values for stack protection. Left is below protected vars,
39 the first pointer in stack corresponding to that offset contains
40 ASAN_STACK_FRAME_MAGIC word, the second pointer to a string describing
41 the frame. Middle is for padding in between variables, right is
42 above the last protected variable and partial immediately after variables
43 up to ASAN_RED_ZONE_SIZE alignment. */
44 #define ASAN_STACK_MAGIC_LEFT 0xf1
45 #define ASAN_STACK_MAGIC_MIDDLE 0xf2
46 #define ASAN_STACK_MAGIC_RIGHT 0xf3
47 #define ASAN_STACK_MAGIC_PARTIAL 0xf4
48
49 #define ASAN_STACK_FRAME_MAGIC 0x41b58ab3
50
51 /* Return true if DECL should be guarded on the stack. */
52
53 static inline bool
54 asan_protect_stack_decl (tree decl)
55 {
56 return DECL_P (decl) && !DECL_ARTIFICIAL (decl);
57 }
58
59 #endif /* TREE_ASAN */