1 /* AddressSanitizer, a fast memory error detector.
2 Copyright (C) 2011-2014 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_function_start (void);
25 extern void asan_finish_file (void);
26 extern rtx asan_emit_stack_protection (rtx, rtx, unsigned int, HOST_WIDE_INT *,
27 tree *, int);
28 extern bool asan_protect_global (tree);
29 extern void initialize_sanitizer_builtins (void);
30 extern tree asan_dynamic_init_call (bool);
31
32 extern gimple_stmt_iterator create_cond_insert_point
33 (gimple_stmt_iterator *, bool, bool, bool, basic_block *, basic_block *);
34
35 /* Alias set for accessing the shadow memory. */
36 extern alias_set_type asan_shadow_set;
37
38 /* Shadow memory is found at
39 (address >> ASAN_SHADOW_SHIFT) + targetm.asan_shadow_offset (). */
40 #define ASAN_SHADOW_SHIFT 3
41
42 /* Red zone size, stack and global variables are padded by ASAN_RED_ZONE_SIZE
43 up to 2 * ASAN_RED_ZONE_SIZE - 1 bytes. */
44 #define ASAN_RED_ZONE_SIZE 32
45
46 /* Shadow memory values for stack protection. Left is below protected vars,
47 the first pointer in stack corresponding to that offset contains
48 ASAN_STACK_FRAME_MAGIC word, the second pointer to a string describing
49 the frame. Middle is for padding in between variables, right is
50 above the last protected variable and partial immediately after variables
51 up to ASAN_RED_ZONE_SIZE alignment. */
52 #define ASAN_STACK_MAGIC_LEFT 0xf1
53 #define ASAN_STACK_MAGIC_MIDDLE 0xf2
54 #define ASAN_STACK_MAGIC_RIGHT 0xf3
55 #define ASAN_STACK_MAGIC_PARTIAL 0xf4
56 #define ASAN_STACK_MAGIC_USE_AFTER_RET 0xf5
57
58 #define ASAN_STACK_FRAME_MAGIC 0x41b58ab3
59 #define ASAN_STACK_RETIRED_MAGIC 0x45e0360e
60
61 /* Return true if DECL should be guarded on the stack. */
62
63 static inline bool
asan_protect_stack_decl(tree decl)64 asan_protect_stack_decl (tree decl)
65 {
66 return DECL_P (decl) && !DECL_ARTIFICIAL (decl);
67 }
68
69 /* Return the size of padding needed to insert after a protected
70 decl of SIZE. */
71
72 static inline unsigned int
asan_red_zone_size(unsigned int size)73 asan_red_zone_size (unsigned int size)
74 {
75 unsigned int c = size & (ASAN_RED_ZONE_SIZE - 1);
76 return c ? 2 * ASAN_RED_ZONE_SIZE - c : ASAN_RED_ZONE_SIZE;
77 }
78
79 #endif /* TREE_ASAN */
80