gdb/i386fbsd-tdep.c

   1 /* Target-dependent code for FreeBSD/i386.
   2
   3    Copyright (C) 2003-2014 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 static 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 \f
 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 }