]>
Commit | Line | Data |
---|---|---|
52a11cbf | 1 | /* Subroutines needed for unwinding stack frames for exception handling. */ |
748086b7 | 2 | /* Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2004, 2009 |
3ef42a0c | 3 | Free Software Foundation, Inc. |
52a11cbf RH |
4 | Contributed by Jason Merrill <jason@cygnus.com>. |
5 | ||
1322177d | 6 | This file is part of GCC. |
52a11cbf | 7 | |
1322177d LB |
8 | GCC is free software; you can redistribute it and/or modify it under |
9 | the terms of the GNU General Public License as published by the Free | |
748086b7 | 10 | Software Foundation; either version 3, or (at your option) any later |
1322177d | 11 | version. |
52a11cbf | 12 | |
1322177d LB |
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
52a11cbf | 17 | |
748086b7 JJ |
18 | Under Section 7 of GPL version 3, you are granted additional |
19 | permissions described in the GCC Runtime Library Exception, version | |
20 | 3.1, as published by the Free Software Foundation. | |
21 | ||
22 | You should have received a copy of the GNU General Public License and | |
23 | a copy of the GCC Runtime Library Exception along with this program; | |
24 | see the files COPYING3 and COPYING.RUNTIME respectively. If not, see | |
25 | <http://www.gnu.org/licenses/>. */ | |
52a11cbf | 26 | |
7ce27103 ZW |
27 | #ifndef GCC_UNWIND_DW2_FDE_H |
28 | #define GCC_UNWIND_DW2_FDE_H | |
52a11cbf | 29 | |
7370bebd | 30 | #ifndef HIDE_EXPORTS |
3fc1f660 | 31 | #pragma GCC visibility push(default) |
7370bebd | 32 | #endif |
3fc1f660 | 33 | |
e1f9550a RH |
34 | struct fde_vector |
35 | { | |
a30794da | 36 | const void *orig_data; |
e1f9550a | 37 | size_t count; |
a30794da | 38 | const struct dwarf_fde *array[]; |
e1f9550a RH |
39 | }; |
40 | ||
52a11cbf | 41 | struct object |
e1f9550a RH |
42 | { |
43 | void *pc_begin; | |
44 | void *tbase; | |
45 | void *dbase; | |
46 | union { | |
a30794da | 47 | const struct dwarf_fde *single; |
e1f9550a RH |
48 | struct dwarf_fde **array; |
49 | struct fde_vector *sort; | |
50 | } u; | |
51 | ||
52 | union { | |
53 | struct { | |
54 | unsigned long sorted : 1; | |
55 | unsigned long from_array : 1; | |
56 | unsigned long mixed_encoding : 1; | |
57 | unsigned long encoding : 8; | |
58 | /* ??? Wish there was an easy way to detect a 64-bit host here; | |
3ef42a0c | 59 | we've got 32 bits left to play with... */ |
e1f9550a RH |
60 | unsigned long count : 21; |
61 | } b; | |
62 | size_t i; | |
63 | } s; | |
64 | ||
3cfe49da GK |
65 | #ifdef DWARF2_OBJECT_END_PTR_EXTENSION |
66 | char *fde_end; | |
67 | #endif | |
68 | ||
e1f9550a RH |
69 | struct object *next; |
70 | }; | |
71 | ||
72 | /* This is the original definition of struct object. While the struct | |
73 | itself was opaque to users, they did know how large it was, and | |
74 | allocate one statically in crtbegin for each DSO. Keep this around | |
75 | so that we're aware of the static size limitations for the new struct. */ | |
76 | struct old_object | |
52a11cbf RH |
77 | { |
78 | void *pc_begin; | |
79 | void *pc_end; | |
80 | struct dwarf_fde *fde_begin; | |
81 | struct dwarf_fde **fde_array; | |
82 | size_t count; | |
e1f9550a | 83 | struct old_object *next; |
52a11cbf RH |
84 | }; |
85 | ||
86 | struct dwarf_eh_bases | |
87 | { | |
88 | void *tbase; | |
89 | void *dbase; | |
90 | void *func; | |
91 | }; | |
92 | ||
93 | ||
a30794da | 94 | extern void __register_frame_info_bases (const void *, struct object *, |
e1f9550a | 95 | void *, void *); |
a30794da | 96 | extern void __register_frame_info (const void *, struct object *); |
52a11cbf | 97 | extern void __register_frame (void *); |
e1f9550a RH |
98 | extern void __register_frame_info_table_bases (void *, struct object *, |
99 | void *, void *); | |
52a11cbf RH |
100 | extern void __register_frame_info_table (void *, struct object *); |
101 | extern void __register_frame_table (void *); | |
a30794da AJ |
102 | extern void *__deregister_frame_info (const void *); |
103 | extern void *__deregister_frame_info_bases (const void *); | |
52a11cbf RH |
104 | extern void __deregister_frame (void *); |
105 | ||
106 | \f | |
107 | typedef int sword __attribute__ ((mode (SI))); | |
108 | typedef unsigned int uword __attribute__ ((mode (SI))); | |
109 | typedef unsigned int uaddr __attribute__ ((mode (pointer))); | |
110 | typedef int saddr __attribute__ ((mode (pointer))); | |
111 | typedef unsigned char ubyte; | |
112 | ||
113 | /* Terminology: | |
114 | CIE - Common Information Element | |
115 | FDE - Frame Descriptor Element | |
116 | ||
117 | There is one per function, and it describes where the function code | |
118 | is located, and what the register lifetimes and stack layout are | |
119 | within the function. | |
120 | ||
eaec9b3d | 121 | The data structures are defined in the DWARF specification, although |
52a11cbf RH |
122 | not in a very readable way (see LITERATURE). |
123 | ||
124 | Every time an exception is thrown, the code needs to locate the FDE | |
125 | for the current function, and starts to look for exception regions | |
126 | from that FDE. This works in a two-level search: | |
127 | a) in a linear search, find the shared image (i.e. DLL) containing | |
128 | the PC | |
129 | b) using the FDE table for that shared object, locate the FDE using | |
41077ce4 | 130 | binary search (which requires the sorting). */ |
52a11cbf RH |
131 | |
132 | /* The first few fields of a CIE. The CIE_id field is 0 for a CIE, | |
133 | to distinguish it from a valid FDE. FDEs are aligned to an addressing | |
134 | unit boundary, but the fields within are unaligned. */ | |
135 | struct dwarf_cie | |
136 | { | |
137 | uword length; | |
138 | sword CIE_id; | |
139 | ubyte version; | |
140 | unsigned char augmentation[]; | |
141 | } __attribute__ ((packed, aligned (__alignof__ (void *)))); | |
142 | ||
143 | /* The first few fields of an FDE. */ | |
144 | struct dwarf_fde | |
145 | { | |
146 | uword length; | |
147 | sword CIE_delta; | |
e1f9550a | 148 | unsigned char pc_begin[]; |
52a11cbf RH |
149 | } __attribute__ ((packed, aligned (__alignof__ (void *)))); |
150 | ||
151 | typedef struct dwarf_fde fde; | |
152 | ||
153 | /* Locate the CIE for a given FDE. */ | |
154 | ||
a30794da AJ |
155 | static inline const struct dwarf_cie * |
156 | get_cie (const struct dwarf_fde *f) | |
52a11cbf | 157 | { |
5f754896 | 158 | return (const void *)&f->CIE_delta - f->CIE_delta; |
52a11cbf RH |
159 | } |
160 | ||
a30794da AJ |
161 | static inline const fde * |
162 | next_fde (const fde *f) | |
52a11cbf | 163 | { |
5f754896 | 164 | return (const fde *) ((const char *) f + f->length + sizeof (f->length)); |
52a11cbf RH |
165 | } |
166 | ||
a30794da | 167 | extern const fde * _Unwind_Find_FDE (void *, struct dwarf_eh_bases *); |
3cfe49da GK |
168 | |
169 | static inline int | |
a30794da | 170 | last_fde (struct object *obj __attribute__ ((__unused__)), const fde *f) |
3cfe49da GK |
171 | { |
172 | #ifdef DWARF2_OBJECT_END_PTR_EXTENSION | |
173 | return (char *)f == obj->fde_end || f->length == 0; | |
174 | #else | |
175 | return f->length == 0; | |
176 | #endif | |
177 | } | |
7ce27103 | 178 | |
7370bebd | 179 | #ifndef HIDE_EXPORTS |
3fc1f660 | 180 | #pragma GCC visibility pop |
7370bebd | 181 | #endif |
3fc1f660 | 182 | |
7ce27103 | 183 | #endif /* unwind-dw2-fde.h */ |