1 /* Subroutines needed for unwinding stack frames for exception handling. */
2 /* Copyright (C) 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
3 Contributed by Jason Merrill <jason@cygnus.com>.
5 This file is part of GCC.
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 2, or (at your option) any later
12 In addition to the permissions in the GNU General Public License, the
13 Free Software Foundation gives you unlimited permission to link the
14 compiled version of this file into combinations with other programs,
15 and to distribute those combinations without any restriction coming
16 from the use of this file. (The General Public License restrictions
17 do apply in other respects; for example, they cover modification of
18 the file, and distribution when not linked into a combine
21 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
22 WARRANTY; without even the implied warranty of MERCHANTABILITY or
23 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
26 You should have received a copy of the GNU General Public License
27 along with GCC; see the file COPYING. If not, write to the Free
28 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
36 struct dwarf_fde
*array
[];
45 struct dwarf_fde
*single
;
46 struct dwarf_fde
**array
;
47 struct fde_vector
*sort
;
52 unsigned long sorted
: 1;
53 unsigned long from_array
: 1;
54 unsigned long mixed_encoding
: 1;
55 unsigned long encoding
: 8;
56 /* ??? Wish there was an easy way to detect a 64-bit host here;
57 we've got 32 bits left to play with... */
58 unsigned long count
: 21;
66 /* This is the original definition of struct object. While the struct
67 itself was opaque to users, they did know how large it was, and
68 allocate one statically in crtbegin for each DSO. Keep this around
69 so that we're aware of the static size limitations for the new struct. */
74 struct dwarf_fde
*fde_begin
;
75 struct dwarf_fde
**fde_array
;
77 struct old_object
*next
;
88 extern void __register_frame_info_bases (void *, struct object
*,
90 extern void __register_frame_info (void *, struct object
*);
91 extern void __register_frame (void *);
92 extern void __register_frame_info_table_bases (void *, struct object
*,
94 extern void __register_frame_info_table (void *, struct object
*);
95 extern void __register_frame_table (void *);
96 extern void *__deregister_frame_info (void *);
97 extern void *__deregister_frame_info_bases (void *);
98 extern void __deregister_frame (void *);
101 typedef int sword
__attribute__ ((mode (SI
)));
102 typedef unsigned int uword
__attribute__ ((mode (SI
)));
103 typedef unsigned int uaddr
__attribute__ ((mode (pointer
)));
104 typedef int saddr
__attribute__ ((mode (pointer
)));
105 typedef unsigned char ubyte
;
108 CIE - Common Information Element
109 FDE - Frame Descriptor Element
111 There is one per function, and it describes where the function code
112 is located, and what the register lifetimes and stack layout are
115 The data structures are defined in the DWARF specfication, although
116 not in a very readable way (see LITERATURE).
118 Every time an exception is thrown, the code needs to locate the FDE
119 for the current function, and starts to look for exception regions
120 from that FDE. This works in a two-level search:
121 a) in a linear search, find the shared image (i.e. DLL) containing
123 b) using the FDE table for that shared object, locate the FDE using
124 binary search (which requires the sorting). */
126 /* The first few fields of a CIE. The CIE_id field is 0 for a CIE,
127 to distinguish it from a valid FDE. FDEs are aligned to an addressing
128 unit boundary, but the fields within are unaligned. */
134 unsigned char augmentation
[];
135 } __attribute__ ((packed
, aligned (__alignof__ (void *))));
137 /* The first few fields of an FDE. */
142 unsigned char pc_begin
[];
143 } __attribute__ ((packed
, aligned (__alignof__ (void *))));
145 typedef struct dwarf_fde fde
;
147 /* Locate the CIE for a given FDE. */
149 static inline struct dwarf_cie
*
150 get_cie (struct dwarf_fde
*f
)
152 return (void *)&f
->CIE_delta
- f
->CIE_delta
;
158 return (fde
*)((char *)f
+ f
->length
+ sizeof (f
->length
));
161 extern fde
* _Unwind_Find_FDE (void *, struct dwarf_eh_bases
*);