]>
Commit | Line | Data |
---|---|---|
52a11cbf | 1 | /* Subroutines needed for unwinding stack frames for exception handling. */ |
711d8c91 | 2 | /* Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2004 |
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 | |
10 | Software Foundation; either version 2, or (at your option) any later | |
11 | version. | |
52a11cbf RH |
12 | |
13 | In addition to the permissions in the GNU General Public License, the | |
14 | Free Software Foundation gives you unlimited permission to link the | |
15 | compiled version of this file into combinations with other programs, | |
16 | and to distribute those combinations without any restriction coming | |
17 | from the use of this file. (The General Public License restrictions | |
18 | do apply in other respects; for example, they cover modification of | |
19 | the file, and distribution when not linked into a combine | |
20 | executable.) | |
21 | ||
1322177d LB |
22 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
23 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
24 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
25 | for more details. | |
52a11cbf RH |
26 | |
27 | You should have received a copy of the GNU General Public License | |
1322177d LB |
28 | along with GCC; see the file COPYING. If not, write to the Free |
29 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
30 | 02111-1307, USA. */ | |
52a11cbf | 31 | |
7ce27103 ZW |
32 | #ifndef GCC_UNWIND_DW2_FDE_H |
33 | #define GCC_UNWIND_DW2_FDE_H | |
52a11cbf | 34 | |
e1f9550a RH |
35 | struct fde_vector |
36 | { | |
a30794da | 37 | const void *orig_data; |
e1f9550a | 38 | size_t count; |
a30794da | 39 | const struct dwarf_fde *array[]; |
e1f9550a RH |
40 | }; |
41 | ||
52a11cbf | 42 | struct object |
e1f9550a RH |
43 | { |
44 | void *pc_begin; | |
45 | void *tbase; | |
46 | void *dbase; | |
47 | union { | |
a30794da | 48 | const struct dwarf_fde *single; |
e1f9550a RH |
49 | struct dwarf_fde **array; |
50 | struct fde_vector *sort; | |
51 | } u; | |
52 | ||
53 | union { | |
54 | struct { | |
55 | unsigned long sorted : 1; | |
56 | unsigned long from_array : 1; | |
57 | unsigned long mixed_encoding : 1; | |
58 | unsigned long encoding : 8; | |
59 | /* ??? Wish there was an easy way to detect a 64-bit host here; | |
3ef42a0c | 60 | we've got 32 bits left to play with... */ |
e1f9550a RH |
61 | unsigned long count : 21; |
62 | } b; | |
63 | size_t i; | |
64 | } s; | |
65 | ||
3cfe49da GK |
66 | #ifdef DWARF2_OBJECT_END_PTR_EXTENSION |
67 | char *fde_end; | |
68 | #endif | |
69 | ||
e1f9550a RH |
70 | struct object *next; |
71 | }; | |
72 | ||
73 | /* This is the original definition of struct object. While the struct | |
74 | itself was opaque to users, they did know how large it was, and | |
75 | allocate one statically in crtbegin for each DSO. Keep this around | |
76 | so that we're aware of the static size limitations for the new struct. */ | |
77 | struct old_object | |
52a11cbf RH |
78 | { |
79 | void *pc_begin; | |
80 | void *pc_end; | |
81 | struct dwarf_fde *fde_begin; | |
82 | struct dwarf_fde **fde_array; | |
83 | size_t count; | |
e1f9550a | 84 | struct old_object *next; |
52a11cbf RH |
85 | }; |
86 | ||
87 | struct dwarf_eh_bases | |
88 | { | |
89 | void *tbase; | |
90 | void *dbase; | |
91 | void *func; | |
92 | }; | |
93 | ||
94 | ||
a30794da | 95 | extern void __register_frame_info_bases (const void *, struct object *, |
e1f9550a | 96 | void *, void *); |
a30794da | 97 | extern void __register_frame_info (const void *, struct object *); |
52a11cbf | 98 | extern void __register_frame (void *); |
e1f9550a RH |
99 | extern void __register_frame_info_table_bases (void *, struct object *, |
100 | void *, void *); | |
52a11cbf RH |
101 | extern void __register_frame_info_table (void *, struct object *); |
102 | extern void __register_frame_table (void *); | |
a30794da AJ |
103 | extern void *__deregister_frame_info (const void *); |
104 | extern void *__deregister_frame_info_bases (const void *); | |
52a11cbf RH |
105 | extern void __deregister_frame (void *); |
106 | ||
107 | \f | |
108 | typedef int sword __attribute__ ((mode (SI))); | |
109 | typedef unsigned int uword __attribute__ ((mode (SI))); | |
110 | typedef unsigned int uaddr __attribute__ ((mode (pointer))); | |
111 | typedef int saddr __attribute__ ((mode (pointer))); | |
112 | typedef unsigned char ubyte; | |
113 | ||
114 | /* Terminology: | |
115 | CIE - Common Information Element | |
116 | FDE - Frame Descriptor Element | |
117 | ||
118 | There is one per function, and it describes where the function code | |
119 | is located, and what the register lifetimes and stack layout are | |
120 | within the function. | |
121 | ||
eaec9b3d | 122 | The data structures are defined in the DWARF specification, although |
52a11cbf RH |
123 | not in a very readable way (see LITERATURE). |
124 | ||
125 | Every time an exception is thrown, the code needs to locate the FDE | |
126 | for the current function, and starts to look for exception regions | |
127 | from that FDE. This works in a two-level search: | |
128 | a) in a linear search, find the shared image (i.e. DLL) containing | |
129 | the PC | |
130 | b) using the FDE table for that shared object, locate the FDE using | |
41077ce4 | 131 | binary search (which requires the sorting). */ |
52a11cbf RH |
132 | |
133 | /* The first few fields of a CIE. The CIE_id field is 0 for a CIE, | |
134 | to distinguish it from a valid FDE. FDEs are aligned to an addressing | |
135 | unit boundary, but the fields within are unaligned. */ | |
136 | struct dwarf_cie | |
137 | { | |
138 | uword length; | |
139 | sword CIE_id; | |
140 | ubyte version; | |
141 | unsigned char augmentation[]; | |
142 | } __attribute__ ((packed, aligned (__alignof__ (void *)))); | |
143 | ||
144 | /* The first few fields of an FDE. */ | |
145 | struct dwarf_fde | |
146 | { | |
147 | uword length; | |
148 | sword CIE_delta; | |
e1f9550a | 149 | unsigned char pc_begin[]; |
52a11cbf RH |
150 | } __attribute__ ((packed, aligned (__alignof__ (void *)))); |
151 | ||
152 | typedef struct dwarf_fde fde; | |
153 | ||
154 | /* Locate the CIE for a given FDE. */ | |
155 | ||
a30794da AJ |
156 | static inline const struct dwarf_cie * |
157 | get_cie (const struct dwarf_fde *f) | |
52a11cbf RH |
158 | { |
159 | return (void *)&f->CIE_delta - f->CIE_delta; | |
160 | } | |
161 | ||
a30794da AJ |
162 | static inline const fde * |
163 | next_fde (const fde *f) | |
52a11cbf | 164 | { |
a30794da | 165 | return (const fde *) ((char *) f + f->length + sizeof (f->length)); |
52a11cbf RH |
166 | } |
167 | ||
a30794da | 168 | extern const fde * _Unwind_Find_FDE (void *, struct dwarf_eh_bases *); |
3cfe49da GK |
169 | |
170 | static inline int | |
a30794da | 171 | last_fde (struct object *obj __attribute__ ((__unused__)), const fde *f) |
3cfe49da GK |
172 | { |
173 | #ifdef DWARF2_OBJECT_END_PTR_EXTENSION | |
174 | return (char *)f == obj->fde_end || f->length == 0; | |
175 | #else | |
176 | return f->length == 0; | |
177 | #endif | |
178 | } | |
7ce27103 ZW |
179 | |
180 | #endif /* unwind-dw2-fde.h */ |