1 /* Target-dependent code for i386 BSD's.
2
3 Copyright (C) 2001-2021 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21 #include "arch-utils.h"
22 #include "frame.h"
23 #include "gdbcore.h"
24 #include "regcache.h"
25 #include "osabi.h"
26
27 #include "i386-tdep.h"
28
29 /* Support for signal handlers. */
30
31 /* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
32 address of the associated sigcontext structure. */
33
34 static CORE_ADDR
i386bsd_sigcontext_addr(struct frame_info * this_frame)35 i386bsd_sigcontext_addr (struct frame_info *this_frame)
36 {
37 struct gdbarch *gdbarch = get_frame_arch (this_frame);
38 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
39 gdb_byte buf[4];
40 CORE_ADDR sp;
41
42 get_frame_register (this_frame, I386_ESP_REGNUM, buf);
43 sp = extract_unsigned_integer (buf, 4, byte_order);
44
45 return read_memory_unsigned_integer (sp + 8, 4, byte_order);
46 }
47
48
49 /* Support for shared libraries. */
50
51 /* Traditional BSD (4.3 BSD, still used for BSDI and 386BSD). */
52
53 /* From <machine/signal.h>. */
54 int i386bsd_sc_reg_offset[] =
55 {
56 -1, /* %eax */
57 -1, /* %ecx */
58 -1, /* %edx */
59 -1, /* %ebx */
60 8 + 0 * 4, /* %esp */
61 8 + 1 * 4, /* %ebp */
62 -1, /* %esi */
63 -1, /* %edi */
64 8 + 3 * 4, /* %eip */
65 8 + 4 * 4, /* %eflags */
66 -1, /* %cs */
67 -1, /* %ss */
68 -1, /* %ds */
69 -1, /* %es */
70 -1, /* %fs */
71 -1 /* %gs */
72 };
73
74 void
i386bsd_init_abi(struct gdbarch_info info,struct gdbarch * gdbarch)75 i386bsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
76 {
77 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
78
79 tdep->jb_pc_offset = 0;
80
81 tdep->sigtramp_start = 0xfdbfdfc0;
82 tdep->sigtramp_end = 0xfdbfe000;
83 tdep->sigcontext_addr = i386bsd_sigcontext_addr;
84 tdep->sc_reg_offset = i386bsd_sc_reg_offset;
85 tdep->sc_num_regs = ARRAY_SIZE (i386bsd_sc_reg_offset);
86 }
87
88
89