gdb/amd64fbsd-tdep.c

   1 /* Target-dependent code for FreeBSD/amd64.
   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 "frame.h"
  23 #include "gdbcore.h"
  24 #include "regcache.h"
  25 #include "osabi.h"
  26
  27 #include "amd64-tdep.h"
  28 #include "bsd-uthread.h"
  29 #include "solib-svr4.h"
  30
  31 /* Support for signal handlers.  */
  32
  33 /* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
  34    address of the associated sigcontext structure.  */
  35
  36 static CORE_ADDR
  37 amd64fbsd_sigcontext_addr (struct frame_info *this_frame)
  38 {
  39   CORE_ADDR sp;
  40
  41   /* The `struct sigcontext' (which really is an `ucontext_t' on
  42      FreeBSD/amd64) lives at a fixed offset in the signal frame.  See
  43      <machine/sigframe.h>.  */
  44   sp = frame_unwind_register_unsigned (this_frame, AMD64_RSP_REGNUM);
  45   return sp + 16;
  46 }
  47 \f
  48 /* FreeBSD 5.1-RELEASE or later.  */
  49
  50 /* Mapping between the general-purpose registers in `struct reg'
  51    format and GDB's register cache layout.
  52
  53    Note that some registers are 32-bit, but since we're little-endian
  54    we get away with that.  */
  55
  56 /* From <machine/reg.h>.  */
  57 static int amd64fbsd_r_reg_offset[] =
  58 {
  59   14 * 8,                       /* %rax */
  60   11 * 8,                       /* %rbx */
  61   13 * 8,                       /* %rcx */
  62   12 * 8,                       /* %rdx */
  63   9 * 8,                        /* %rsi */
  64   8 * 8,                        /* %rdi */
  65   10 * 8,                       /* %rbp */
  66   20 * 8,                       /* %rsp */
  67   7 * 8,                        /* %r8 ...  */
  68   6 * 8,
  69   5 * 8,
  70   4 * 8,
  71   3 * 8,
  72   2 * 8,
  73   1 * 8,
  74   0 * 8,                        /* ... %r15 */
  75   17 * 8,                       /* %rip */
  76   19 * 8,                       /* %eflags */
  77   18 * 8,                       /* %cs */
  78   21 * 8,                       /* %ss */
  79   -1,                           /* %ds */
  80   -1,                           /* %es */
  81   -1,                           /* %fs */
  82   -1                            /* %gs */
  83 };
  84
  85 /* Location of the signal trampoline.  */
  86 CORE_ADDR amd64fbsd_sigtramp_start_addr = 0x7fffffffffc0ULL;
  87 CORE_ADDR amd64fbsd_sigtramp_end_addr = 0x7fffffffffe0ULL;
  88
  89 /* From <machine/signal.h>.  */
  90 int amd64fbsd_sc_reg_offset[] =
  91 {
  92   24 + 6 * 8,                   /* %rax */
  93   24 + 7 * 8,                   /* %rbx */
  94   24 + 3 * 8,                   /* %rcx */
  95   24 + 2 * 8,                   /* %rdx */
  96   24 + 1 * 8,                   /* %rsi */
  97   24 + 0 * 8,                   /* %rdi */
  98   24 + 8 * 8,                   /* %rbp */
  99   24 + 22 * 8,                  /* %rsp */
 100   24 + 4 * 8,                   /* %r8 ...  */
 101   24 + 5 * 8,
 102   24 + 9 * 8,
 103   24 + 10 * 8,
 104   24 + 11 * 8,
 105   24 + 12 * 8,
 106   24 + 13 * 8,
 107   24 + 14 * 8,                  /* ... %r15 */
 108   24 + 19 * 8,                  /* %rip */
 109   24 + 21 * 8,                  /* %eflags */
 110   24 + 20 * 8,                  /* %cs */
 111   24 + 23 * 8,                  /* %ss */
 112   -1,                           /* %ds */
 113   -1,                           /* %es */
 114   -1,                           /* %fs */
 115   -1                            /* %gs */
 116 };
 117
 118 /* From /usr/src/lib/libc/amd64/gen/_setjmp.S.  */
 119 static int amd64fbsd_jmp_buf_reg_offset[] =
 120 {
 121   -1,                           /* %rax */
 122   1 * 8,                        /* %rbx */
 123   -1,                           /* %rcx */
 124   -1,                           /* %rdx */
 125   -1,                           /* %rsi */
 126   -1,                           /* %rdi */
 127   3 * 8,                        /* %rbp */
 128   2 * 8,                        /* %rsp */
 129   -1,                           /* %r8 ...  */
 130   -1,
 131   -1,
 132   -1,                           /* ... %r11 */
 133   4 * 8,                        /* %r12 ...  */
 134   5 * 8,
 135   6 * 8,
 136   7 * 8,                        /* ... %r15 */
 137   0 * 8                         /* %rip */
 138 };
 139
 140 static void
 141 amd64fbsd_supply_uthread (struct regcache *regcache,
 142                           int regnum, CORE_ADDR addr)
 143 {
 144   gdb_byte buf[8];
 145   int i;
 146
 147   gdb_assert (regnum >= -1);
 148
 149   for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
 150     {
 151       if (amd64fbsd_jmp_buf_reg_offset[i] != -1
 152           && (regnum == -1 || regnum == i))
 153         {
 154           read_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
 155           regcache_raw_supply (regcache, i, buf);
 156         }
 157     }
 158 }
 159
 160 static void
 161 amd64fbsd_collect_uthread (const struct regcache *regcache,
 162                            int regnum, CORE_ADDR addr)
 163 {
 164   gdb_byte buf[8];
 165   int i;
 166
 167   gdb_assert (regnum >= -1);
 168
 169   for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
 170     {
 171       if (amd64fbsd_jmp_buf_reg_offset[i] != -1
 172           && (regnum == -1 || regnum == i))
 173         {
 174           regcache_raw_collect (regcache, i, buf);
 175           write_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
 176         }
 177     }
 178 }
 179
 180 static void
 181 amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 182 {
 183   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 184
 185   /* Obviously FreeBSD is BSD-based.  */
 186   i386bsd_init_abi (info, gdbarch);
 187
 188   tdep->gregset_reg_offset = amd64fbsd_r_reg_offset;
 189   tdep->gregset_num_regs = ARRAY_SIZE (amd64fbsd_r_reg_offset);
 190   tdep->sizeof_gregset = 22 * 8;
 191
 192   amd64_init_abi (info, gdbarch);
 193
 194   tdep->sigtramp_start = amd64fbsd_sigtramp_start_addr;
 195   tdep->sigtramp_end = amd64fbsd_sigtramp_end_addr;
 196   tdep->sigcontext_addr = amd64fbsd_sigcontext_addr;
 197   tdep->sc_reg_offset = amd64fbsd_sc_reg_offset;
 198   tdep->sc_num_regs = ARRAY_SIZE (amd64fbsd_sc_reg_offset);
 199
 200   /* FreeBSD provides a user-level threads implementation.  */
 201   bsd_uthread_set_supply_uthread (gdbarch, amd64fbsd_supply_uthread);
 202   bsd_uthread_set_collect_uthread (gdbarch, amd64fbsd_collect_uthread);
 203
 204   /* FreeBSD uses SVR4-style shared libraries.  */
 205   set_solib_svr4_fetch_link_map_offsets
 206     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 207 }
 208 \f
 209
 210 /* Provide a prototype to silence -Wmissing-prototypes.  */
 211 void _initialize_amd64fbsd_tdep (void);
 212
 213 void
 214 _initialize_amd64fbsd_tdep (void)
 215 {
 216   gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
 217                           GDB_OSABI_FREEBSD_ELF, amd64fbsd_init_abi);
 218 }