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