gdb/i386fbsd-tdep.c

   1 /* Target-dependent code for FreeBSD/i386.
   2
   3    Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "arch-utils.h"
  23 #include "gdbcore.h"
  24 #include "osabi.h"
  25 #include "regcache.h"
  26
  27 #include "gdb_assert.h"
  28
  29 #include "i386-tdep.h"
  30 #include "i387-tdep.h"
  31 #include "bsd-uthread.h"
  32 #include "solib-svr4.h"
  33
  34 /* FreeBSD 3.0-RELEASE or later.  */
  35
  36 /* From <machine/reg.h>.  */
  37 static int i386fbsd_r_reg_offset[] =
  38 {
  39   9 * 4, 8 * 4, 7 * 4, 6 * 4,   /* %eax, %ecx, %edx, %ebx */
  40   15 * 4, 4 * 4,                /* %esp, %ebp */
  41   3 * 4, 2 * 4,                 /* %esi, %edi */
  42   12 * 4, 14 * 4,               /* %eip, %eflags */
  43   13 * 4, 16 * 4,               /* %cs, %ss */
  44   1 * 4, 0 * 4, -1, -1          /* %ds, %es, %fs, %gs */
  45 };
  46
  47 /* Sigtramp routine location.  */
  48 CORE_ADDR i386fbsd_sigtramp_start_addr = 0xbfbfdf20;
  49 CORE_ADDR i386fbsd_sigtramp_end_addr = 0xbfbfdff0;
  50
  51 /* From <machine/signal.h>.  */
  52 int i386fbsd_sc_reg_offset[] =
  53 {
  54   8 + 14 * 4,                   /* %eax */
  55   8 + 13 * 4,                   /* %ecx */
  56   8 + 12 * 4,                   /* %edx */
  57   8 + 11 * 4,                   /* %ebx */
  58   8 + 0 * 4,                    /* %esp */
  59   8 + 1 * 4,                    /* %ebp */
  60   8 + 10 * 4,                   /* %esi */
  61   8 + 9 * 4,                    /* %edi */
  62   8 + 3 * 4,                    /* %eip */
  63   8 + 4 * 4,                    /* %eflags */
  64   8 + 7 * 4,                    /* %cs */
  65   8 + 8 * 4,                    /* %ss */
  66   8 + 6 * 4,                    /* %ds */
  67   8 + 5 * 4,                    /* %es */
  68   8 + 15 * 4,                   /* %fs */
  69   8 + 16 * 4                    /* %gs */
  70 };
  71
  72 /* From /usr/src/lib/libc/i386/gen/_setjmp.S.  */
  73 static int i386fbsd_jmp_buf_reg_offset[] =
  74 {
  75   -1,                           /* %eax */
  76   -1,                           /* %ecx */
  77   -1,                           /* %edx */
  78   1 * 4,                        /* %ebx */
  79   2 * 4,                        /* %esp */
  80   3 * 4,                        /* %ebp */
  81   4 * 4,                        /* %esi */
  82   5 * 4,                        /* %edi */
  83   0 * 4                         /* %eip */
  84 };
  85
  86 static void
  87 i386fbsd_supply_uthread (struct regcache *regcache,
  88                          int regnum, CORE_ADDR addr)
  89 {
  90   char buf[4];
  91   int i;
  92
  93   gdb_assert (regnum >= -1);
  94
  95   for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
  96     {
  97       if (i386fbsd_jmp_buf_reg_offset[i] != -1
  98           && (regnum == -1 || regnum == i))
  99         {
 100           read_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
 101           regcache_raw_supply (regcache, i, buf);
 102         }
 103     }
 104 }
 105
 106 static void
 107 i386fbsd_collect_uthread (const struct regcache *regcache,
 108                           int regnum, CORE_ADDR addr)
 109 {
 110   char buf[4];
 111   int i;
 112
 113   gdb_assert (regnum >= -1);
 114
 115   for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
 116     {
 117       if (i386fbsd_jmp_buf_reg_offset[i] != -1
 118           && (regnum == -1 || regnum == i))
 119         {
 120           regcache_raw_collect (regcache, i, buf);
 121           write_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
 122         }
 123     }
 124 }
 125
 126 static void
 127 i386fbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 128 {
 129   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 130
 131   /* Obviously FreeBSD is BSD-based.  */
 132   i386bsd_init_abi (info, gdbarch);
 133
 134   /* FreeBSD has a different `struct reg', and reserves some space for
 135      its FPU emulator in `struct fpreg'.  */
 136   tdep->gregset_reg_offset = i386fbsd_r_reg_offset;
 137   tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd_r_reg_offset);
 138   tdep->sizeof_gregset = 18 * 4;
 139   tdep->sizeof_fpregset = 176;
 140
 141   /* FreeBSD uses -freg-struct-return by default.  */
 142   tdep->struct_return = reg_struct_return;
 143
 144   /* FreeBSD uses a different memory layout.  */
 145   tdep->sigtramp_start = i386fbsd_sigtramp_start_addr;
 146   tdep->sigtramp_end = i386fbsd_sigtramp_end_addr;
 147
 148   /* FreeBSD has a more complete `struct sigcontext'.  */
 149   tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
 150   tdep->sc_num_regs = ARRAY_SIZE (i386fbsd_sc_reg_offset);
 151
 152   /* FreeBSD provides a user-level threads implementation.  */
 153   bsd_uthread_set_supply_uthread (gdbarch, i386fbsd_supply_uthread);
 154   bsd_uthread_set_collect_uthread (gdbarch, i386fbsd_collect_uthread);
 155 }
 156
 157 static void
 158 i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 159 {
 160   /* It's almost identical to FreeBSD a.out.  */
 161   i386fbsdaout_init_abi (info, gdbarch);
 162
 163   /* Except that it uses ELF.  */
 164   i386_elf_init_abi (info, gdbarch);
 165
 166   /* FreeBSD ELF uses SVR4-style shared libraries.  */
 167   set_solib_svr4_fetch_link_map_offsets
 168     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
 169 }
 170
 171 /* FreeBSD 4.0-RELEASE or later.  */
 172
 173 /* From <machine/reg.h>.  */
 174 static int i386fbsd4_r_reg_offset[] =
 175 {
 176   10 * 4, 9 * 4, 8 * 4, 7 * 4,  /* %eax, %ecx, %edx, %ebx */
 177   16 * 4, 5 * 4,                /* %esp, %ebp */
 178   4 * 4, 3 * 4,                 /* %esi, %edi */
 179   13 * 4, 15 * 4,               /* %eip, %eflags */
 180   14 * 4, 17 * 4,               /* %cs, %ss */
 181   2 * 4, 1 * 4, 0 * 4, 18 * 4   /* %ds, %es, %fs, %gs */
 182 };
 183
 184 /* From <machine/signal.h>.  */
 185 int i386fbsd4_sc_reg_offset[] =
 186 {
 187   20 + 11 * 4,                  /* %eax */
 188   20 + 10 * 4,                  /* %ecx */
 189   20 + 9 * 4,                   /* %edx */
 190   20 + 8 * 4,                   /* %ebx */
 191   20 + 17 * 4,                  /* %esp */
 192   20 + 6 * 4,                   /* %ebp */
 193   20 + 5 * 4,                   /* %esi */
 194   20 + 4 * 4,                   /* %edi */
 195   20 + 14 * 4,                  /* %eip */
 196   20 + 16 * 4,                  /* %eflags */
 197   20 + 15 * 4,                  /* %cs */
 198   20 + 18 * 4,                  /* %ss */
 199   20 + 3 * 4,                   /* %ds */
 200   20 + 2 * 4,                   /* %es */
 201   20 + 1 * 4,                   /* %fs */
 202   20 + 0 * 4                    /* %gs */
 203 };
 204
 205 static void
 206 i386fbsd4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 207 {
 208   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 209
 210   /* Inherit stuff from older releases.  We assume that FreeBSD
 211      4.0-RELEASE always uses ELF.  */
 212   i386fbsd_init_abi (info, gdbarch);
 213
 214   /* FreeBSD 4.0 introduced a new `struct reg'.  */
 215   tdep->gregset_reg_offset = i386fbsd4_r_reg_offset;
 216   tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd4_r_reg_offset);
 217   tdep->sizeof_gregset = 19 * 4;
 218
 219   /* FreeBSD 4.0 introduced a new `struct sigcontext'.  */
 220   tdep->sc_reg_offset = i386fbsd4_sc_reg_offset;
 221   tdep->sc_num_regs = ARRAY_SIZE (i386fbsd4_sc_reg_offset);
 222 }
 223
 224 \f
 225 /* Provide a prototype to silence -Wmissing-prototypes.  */
 226 void _initialize_i386fbsd_tdep (void);
 227
 228 void
 229 _initialize_i386fbsd_tdep (void)
 230 {
 231   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_AOUT,
 232                           i386fbsdaout_init_abi);
 233   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_ELF,
 234                           i386fbsd4_init_abi);
 235 }