xref: /dragonfly/contrib/gdb-7/gdb/i386fbsd-tdep.c (revision d4ef6694)
1 /* Target-dependent code for FreeBSD/i386.
2 
3    Copyright (C) 2003-2013 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 "gdbcore.h"
23 #include "osabi.h"
24 #include "regcache.h"
25 
26 #include "gdb_assert.h"
27 
28 #include "i386-tdep.h"
29 #include "i387-tdep.h"
30 #include "bsd-uthread.h"
31 #include "solib-svr4.h"
32 
33 /* FreeBSD 3.0-RELEASE or later.  */
34 
35 /* From <machine/reg.h>.  */
36 static int i386fbsd_r_reg_offset[] =
37 {
38   9 * 4, 8 * 4, 7 * 4, 6 * 4,	/* %eax, %ecx, %edx, %ebx */
39   15 * 4, 4 * 4,		/* %esp, %ebp */
40   3 * 4, 2 * 4,			/* %esi, %edi */
41   12 * 4, 14 * 4,		/* %eip, %eflags */
42   13 * 4, 16 * 4,		/* %cs, %ss */
43   1 * 4, 0 * 4, -1, -1		/* %ds, %es, %fs, %gs */
44 };
45 
46 /* Sigtramp routine location.  */
47 CORE_ADDR i386fbsd_sigtramp_start_addr = 0xbfbfdf20;
48 CORE_ADDR i386fbsd_sigtramp_end_addr = 0xbfbfdff0;
49 
50 /* From <machine/signal.h>.  */
51 int i386fbsd_sc_reg_offset[] =
52 {
53   8 + 14 * 4,			/* %eax */
54   8 + 13 * 4,			/* %ecx */
55   8 + 12 * 4,			/* %edx */
56   8 + 11 * 4,			/* %ebx */
57   8 + 0 * 4,                    /* %esp */
58   8 + 1 * 4,                    /* %ebp */
59   8 + 10 * 4,                   /* %esi */
60   8 + 9 * 4,                    /* %edi */
61   8 + 3 * 4,                    /* %eip */
62   8 + 4 * 4,                    /* %eflags */
63   8 + 7 * 4,                    /* %cs */
64   8 + 8 * 4,                    /* %ss */
65   8 + 6 * 4,                    /* %ds */
66   8 + 5 * 4,                    /* %es */
67   8 + 15 * 4,			/* %fs */
68   8 + 16 * 4			/* %gs */
69 };
70 
71 /* From /usr/src/lib/libc/i386/gen/_setjmp.S.  */
72 static int i386fbsd_jmp_buf_reg_offset[] =
73 {
74   -1,				/* %eax */
75   -1,				/* %ecx */
76   -1,				/* %edx */
77   1 * 4,			/* %ebx */
78   2 * 4,			/* %esp */
79   3 * 4,			/* %ebp */
80   4 * 4,			/* %esi */
81   5 * 4,			/* %edi */
82   0 * 4				/* %eip */
83 };
84 
85 static void
86 i386fbsd_supply_uthread (struct regcache *regcache,
87 			 int regnum, CORE_ADDR addr)
88 {
89   gdb_byte buf[4];
90   int i;
91 
92   gdb_assert (regnum >= -1);
93 
94   for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
95     {
96       if (i386fbsd_jmp_buf_reg_offset[i] != -1
97 	  && (regnum == -1 || regnum == i))
98 	{
99 	  read_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
100 	  regcache_raw_supply (regcache, i, buf);
101 	}
102     }
103 }
104 
105 static void
106 i386fbsd_collect_uthread (const struct regcache *regcache,
107 			  int regnum, CORE_ADDR addr)
108 {
109   gdb_byte buf[4];
110   int i;
111 
112   gdb_assert (regnum >= -1);
113 
114   for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
115     {
116       if (i386fbsd_jmp_buf_reg_offset[i] != -1
117 	  && (regnum == -1 || regnum == i))
118 	{
119 	  regcache_raw_collect (regcache, i, buf);
120 	  write_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
121 	}
122     }
123 }
124 
125 static void
126 i386fbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
127 {
128   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
129 
130   /* Obviously FreeBSD is BSD-based.  */
131   i386bsd_init_abi (info, gdbarch);
132 
133   /* FreeBSD has a different `struct reg', and reserves some space for
134      its FPU emulator in `struct fpreg'.  */
135   tdep->gregset_reg_offset = i386fbsd_r_reg_offset;
136   tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd_r_reg_offset);
137   tdep->sizeof_gregset = 18 * 4;
138   tdep->sizeof_fpregset = 176;
139 
140   /* FreeBSD uses -freg-struct-return by default.  */
141   tdep->struct_return = reg_struct_return;
142 
143   /* FreeBSD uses a different memory layout.  */
144   tdep->sigtramp_start = i386fbsd_sigtramp_start_addr;
145   tdep->sigtramp_end = i386fbsd_sigtramp_end_addr;
146 
147   /* FreeBSD has a more complete `struct sigcontext'.  */
148   tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
149   tdep->sc_num_regs = ARRAY_SIZE (i386fbsd_sc_reg_offset);
150 
151   /* FreeBSD provides a user-level threads implementation.  */
152   bsd_uthread_set_supply_uthread (gdbarch, i386fbsd_supply_uthread);
153   bsd_uthread_set_collect_uthread (gdbarch, i386fbsd_collect_uthread);
154 }
155 
156 static void
157 i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
158 {
159   /* It's almost identical to FreeBSD a.out.  */
160   i386fbsdaout_init_abi (info, gdbarch);
161 
162   /* Except that it uses ELF.  */
163   i386_elf_init_abi (info, gdbarch);
164 
165   /* FreeBSD ELF uses SVR4-style shared libraries.  */
166   set_solib_svr4_fetch_link_map_offsets
167     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
168 }
169 
170 /* FreeBSD 4.0-RELEASE or later.  */
171 
172 /* From <machine/reg.h>.  */
173 static int i386fbsd4_r_reg_offset[] =
174 {
175   10 * 4, 9 * 4, 8 * 4, 7 * 4,	/* %eax, %ecx, %edx, %ebx */
176   16 * 4, 5 * 4,		/* %esp, %ebp */
177   4 * 4, 3 * 4,			/* %esi, %edi */
178   13 * 4, 15 * 4,		/* %eip, %eflags */
179   14 * 4, 17 * 4,		/* %cs, %ss */
180   2 * 4, 1 * 4, 0 * 4, 18 * 4	/* %ds, %es, %fs, %gs */
181 };
182 
183 /* From <machine/signal.h>.  */
184 int i386fbsd4_sc_reg_offset[] =
185 {
186   20 + 11 * 4,			/* %eax */
187   20 + 10 * 4,			/* %ecx */
188   20 + 9 * 4,			/* %edx */
189   20 + 8 * 4,			/* %ebx */
190   20 + 17 * 4,			/* %esp */
191   20 + 6 * 4,			/* %ebp */
192   20 + 5 * 4,			/* %esi */
193   20 + 4 * 4,			/* %edi */
194   20 + 14 * 4,			/* %eip */
195   20 + 16 * 4,			/* %eflags */
196   20 + 15 * 4,			/* %cs */
197   20 + 18 * 4,			/* %ss */
198   20 + 3 * 4,			/* %ds */
199   20 + 2 * 4,			/* %es */
200   20 + 1 * 4,			/* %fs */
201   20 + 0 * 4			/* %gs */
202 };
203 
204 void
205 i386fbsd4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
206 {
207   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
208 
209   /* Inherit stuff from older releases.  We assume that FreeBSD
210      4.0-RELEASE always uses ELF.  */
211   i386fbsd_init_abi (info, gdbarch);
212 
213   /* FreeBSD 4.0 introduced a new `struct reg'.  */
214   tdep->gregset_reg_offset = i386fbsd4_r_reg_offset;
215   tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd4_r_reg_offset);
216   tdep->sizeof_gregset = 19 * 4;
217 
218   /* FreeBSD 4.0 introduced a new `struct sigcontext'.  */
219   tdep->sc_reg_offset = i386fbsd4_sc_reg_offset;
220   tdep->sc_num_regs = ARRAY_SIZE (i386fbsd4_sc_reg_offset);
221 }
222 
223 
224 /* Provide a prototype to silence -Wmissing-prototypes.  */
225 void _initialize_i386fbsd_tdep (void);
226 
227 void
228 _initialize_i386fbsd_tdep (void)
229 {
230   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_AOUT,
231 			  i386fbsdaout_init_abi);
232   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_ELF,
233 			  i386fbsd4_init_abi);
234 }
235