gdb/i386fbsd-tdep.c

   1 /* Target-dependent code for FreeBSD/i386.
   2
   3    Copyright 2003, 2004, 2005 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 2 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, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "arch-utils.h"
  24 #include "gdbcore.h"
  25 #include "osabi.h"
  26 #include "regcache.h"
  27
  28 #include "gdb_assert.h"
  29
  30 #include "i386-tdep.h"
  31 #include "i387-tdep.h"
  32 #include "bsd-uthread.h"
  33 #include "solib-svr4.h"
  34
  35 /* FreeBSD 3.0-RELEASE or later.  */
  36
  37 /* From <machine/reg.h>.  */
  38 static int i386fbsd_r_reg_offset[] =
  39 {
  40   9 * 4, 8 * 4, 7 * 4, 6 * 4,   /* %eax, %ecx, %edx, %ebx */
  41   15 * 4, 4 * 4,                /* %esp, %ebp */
  42   3 * 4, 2 * 4,                 /* %esi, %edi */
  43   12 * 4, 14 * 4,               /* %eip, %eflags */
  44   13 * 4, 16 * 4,               /* %cs, %ss */
  45   1 * 4, 0 * 4, -1, -1          /* %ds, %es, %fs, %gs */
  46 };
  47
  48 /* Sigtramp routine location.  */
  49 CORE_ADDR i386fbsd_sigtramp_start_addr = 0xbfbfdf20;
  50 CORE_ADDR i386fbsd_sigtramp_end_addr = 0xbfbfdff0;
  51
  52 /* From <machine/signal.h>.  */
  53 static int i386fbsd_sc_reg_offset[] =
  54 {
  55   8 + 14 * 4,                   /* %eax */
  56   8 + 13 * 4,                   /* %ecx */
  57   8 + 12 * 4,                   /* %edx */
  58   8 + 11 * 4,                   /* %ebx */
  59   8 + 0 * 4,                    /* %esp */
  60   8 + 1 * 4,                    /* %ebp */
  61   8 + 10 * 4,                   /* %esi */
  62   8 + 9 * 4,                    /* %edi */
  63   8 + 3 * 4,                    /* %eip */
  64   8 + 4 * 4,                    /* %eflags */
  65   8 + 7 * 4,                    /* %cs */
  66   8 + 8 * 4,                    /* %ss */
  67   8 + 6 * 4,                    /* %ds */
  68   8 + 5 * 4,                    /* %es */
  69   8 + 15 * 4,                   /* %fs */
  70   8 + 16 * 4                    /* %gs */
  71 };
  72
  73 /* From /usr/src/lib/libc/i386/gen/_setjmp.S.  */
  74 static int i386fbsd_jmp_buf_reg_offset[] =
  75 {
  76   -1,                           /* %eax */
  77   -1,                           /* %ecx */
  78   -1,                           /* %edx */
  79   1 * 4,                        /* %ebx */
  80   2 * 4,                        /* %esp */
  81   3 * 4,                        /* %ebp */
  82   4 * 4,                        /* %esi */
  83   5 * 4,                        /* %edi */
  84   0 * 4                         /* %eip */
  85 };
  86
  87 static void
  88 i386fbsd_supply_uthread (struct regcache *regcache,
  89                          int regnum, CORE_ADDR addr)
  90 {
  91   char buf[4];
  92   int i;
  93
  94   gdb_assert (regnum >= -1);
  95
  96   for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
  97     {
  98       if (i386fbsd_jmp_buf_reg_offset[i] != -1
  99           && (regnum == -1 || regnum == i))
 100         {
 101           read_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
 102           regcache_raw_supply (regcache, i, buf);
 103         }
 104     }
 105 }
 106
 107 static void
 108 i386fbsd_collect_uthread (const struct regcache *regcache,
 109                           int regnum, CORE_ADDR addr)
 110 {
 111   char buf[4];
 112   int i;
 113
 114   gdb_assert (regnum >= -1);
 115
 116   for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
 117     {
 118       if (i386fbsd_jmp_buf_reg_offset[i] != -1
 119           && (regnum == -1 || regnum == i))
 120         {
 121           regcache_raw_collect (regcache, i, buf);
 122           write_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
 123         }
 124     }
 125 }
 126
 127 static void
 128 i386fbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 129 {
 130   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 131
 132   /* Obviously FreeBSD is BSD-based.  */
 133   i386bsd_init_abi (info, gdbarch);
 134
 135   /* FreeBSD has a different `struct reg', and reserves some space for
 136      its FPU emulator in `struct fpreg'.  */
 137   tdep->gregset_reg_offset = i386fbsd_r_reg_offset;
 138   tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd_r_reg_offset);
 139   tdep->sizeof_gregset = 18 * 4;
 140   tdep->sizeof_fpregset = 176;
 141
 142   /* FreeBSD uses -freg-struct-return by default.  */
 143   tdep->struct_return = reg_struct_return;
 144
 145   /* FreeBSD uses a different memory layout.  */
 146   tdep->sigtramp_start = i386fbsd_sigtramp_start_addr;
 147   tdep->sigtramp_end = i386fbsd_sigtramp_end_addr;
 148
 149   /* FreeBSD has a more complete `struct sigcontext'.  */
 150   tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
 151   tdep->sc_num_regs = ARRAY_SIZE (i386fbsd_sc_reg_offset);
 152
 153   /* FreeBSD provides a user-level threads implementation.  */
 154   bsd_uthread_set_supply_uthread (gdbarch, i386fbsd_supply_uthread);
 155   bsd_uthread_set_collect_uthread (gdbarch, i386fbsd_collect_uthread);
 156 }
 157
 158 static void
 159 i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 160 {
 161   /* It's almost identical to FreeBSD a.out.  */
 162   i386fbsdaout_init_abi (info, gdbarch);
 163
 164   /* Except that it uses ELF.  */
 165   i386_elf_init_abi (info, gdbarch);
 166
 167   /* FreeBSD ELF uses SVR4-style shared libraries.  */
 168   set_solib_svr4_fetch_link_map_offsets
 169     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
 170 }
 171
 172 /* FreeBSD 4.0-RELEASE or later.  */
 173
 174 /* From <machine/reg.h>.  */
 175 static int i386fbsd4_r_reg_offset[] =
 176 {
 177   10 * 4, 9 * 4, 8 * 4, 7 * 4,  /* %eax, %ecx, %edx, %ebx */
 178   16 * 4, 5 * 4,                /* %esp, %ebp */
 179   4 * 4, 3 * 4,                 /* %esi, %edi */
 180   13 * 4, 15 * 4,               /* %eip, %eflags */
 181   14 * 4, 17 * 4,               /* %cs, %ss */
 182   2 * 4, 1 * 4, 0 * 4, 18 * 4   /* %ds, %es, %fs, %gs */
 183 };
 184
 185 /* From <machine/signal.h>.  */
 186 int i386fbsd4_sc_reg_offset[] =
 187 {
 188   20 + 11 * 4,                  /* %eax */
 189   20 + 10 * 4,                  /* %ecx */
 190   20 + 9 * 4,                   /* %edx */
 191   20 + 8 * 4,                   /* %ebx */
 192   20 + 17 * 4,                  /* %esp */
 193   20 + 6 * 4,                   /* %ebp */
 194   20 + 5 * 4,                   /* %esi */
 195   20 + 4 * 4,                   /* %edi */
 196   20 + 14 * 4,                  /* %eip */
 197   20 + 16 * 4,                  /* %eflags */
 198   20 + 15 * 4,                  /* %cs */
 199   20 + 18 * 4,                  /* %ss */
 200   20 + 3 * 4,                   /* %ds */
 201   20 + 2 * 4,                   /* %es */
 202   20 + 1 * 4,                   /* %fs */
 203   20 + 0 * 4                    /* %gs */
 204 };
 205
 206 static void
 207 i386fbsd4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 208 {
 209   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 210
 211   /* Inherit stuff from older releases.  We assume that FreeBSD
 212      4.0-RELEASE always uses ELF.  */
 213   i386fbsd_init_abi (info, gdbarch);
 214
 215   /* FreeBSD 4.0 introduced a new `struct reg'.  */
 216   tdep->gregset_reg_offset = i386fbsd4_r_reg_offset;
 217   tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd4_r_reg_offset);
 218   tdep->sizeof_gregset = 19 * 4;
 219
 220   /* FreeBSD 4.0 introduced a new `struct sigcontext'.  */
 221   tdep->sc_reg_offset = i386fbsd4_sc_reg_offset;
 222   tdep->sc_num_regs = ARRAY_SIZE (i386fbsd4_sc_reg_offset);
 223 }
 224
 225 \f
 226 /* Provide a prototype to silence -Wmissing-prototypes.  */
 227 void _initialize_i386fbsd_tdep (void);
 228
 229 void
 230 _initialize_i386fbsd_tdep (void)
 231 {
 232   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_AOUT,
 233                           i386fbsdaout_init_abi);
 234   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_ELF,
 235                           i386fbsd4_init_abi);
 236 }