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 "gdb_assert.h"
  28 #include <string.h>
  29
  30 #include "amd64-tdep.h"
  31 #include "bsd-uthread.h"
  32 #include "solib-svr4.h"
  33
  34 /* Support for signal handlers.  */
  35
  36 /* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
  37    address of the associated sigcontext structure.  */
  38
  39 static CORE_ADDR
  40 amd64fbsd_sigcontext_addr (struct frame_info *this_frame)
  41 {
  42   CORE_ADDR sp;
  43
  44   /* The `struct sigcontext' (which really is an `ucontext_t' on
  45      FreeBSD/amd64) lives at a fixed offset in the signal frame.  See
  46      <machine/sigframe.h>.  */
  47   sp = frame_unwind_register_unsigned (this_frame, AMD64_RSP_REGNUM);
  48   return sp + 16;
  49 }
  50 \f
  51 /* FreeBSD 5.1-RELEASE or later.  */
  52
  53 /* Mapping between the general-purpose registers in `struct reg'
  54    format and GDB's register cache layout.
  55
  56    Note that some registers are 32-bit, but since we're little-endian
  57    we get away with that.  */
  58
  59 /* From <machine/reg.h>.  */
  60 static int amd64fbsd_r_reg_offset[] =
  61 {
  62   14 * 8,                       /* %rax */
  63   11 * 8,                       /* %rbx */
  64   13 * 8,                       /* %rcx */
  65   12 * 8,                       /* %rdx */
  66   9 * 8,                        /* %rsi */
  67   8 * 8,                        /* %rdi */
  68   10 * 8,                       /* %rbp */
  69   20 * 8,                       /* %rsp */
  70   7 * 8,                        /* %r8 ...  */
  71   6 * 8,
  72   5 * 8,
  73   4 * 8,
  74   3 * 8,
  75   2 * 8,
  76   1 * 8,
  77   0 * 8,                        /* ... %r15 */
  78   17 * 8,                       /* %rip */
  79   19 * 8,                       /* %eflags */
  80   18 * 8,                       /* %cs */
  81   21 * 8,                       /* %ss */
  82   -1,                           /* %ds */
  83   -1,                           /* %es */
  84   -1,                           /* %fs */
  85   -1                            /* %gs */
  86 };
  87
  88 /* Location of the signal trampoline.  */
  89 CORE_ADDR amd64fbsd_sigtramp_start_addr = 0x7fffffffffc0ULL;
  90 CORE_ADDR amd64fbsd_sigtramp_end_addr = 0x7fffffffffe0ULL;
  91
  92 /* From <machine/signal.h>.  */
  93 int amd64fbsd_sc_reg_offset[] =
  94 {
  95   24 + 6 * 8,                   /* %rax */
  96   24 + 7 * 8,                   /* %rbx */
  97   24 + 3 * 8,                   /* %rcx */
  98   24 + 2 * 8,                   /* %rdx */
  99   24 + 1 * 8,                   /* %rsi */
 100   24 + 0 * 8,                   /* %rdi */
 101   24 + 8 * 8,                   /* %rbp */
 102   24 + 22 * 8,                  /* %rsp */
 103   24 + 4 * 8,                   /* %r8 ...  */
 104   24 + 5 * 8,
 105   24 + 9 * 8,
 106   24 + 10 * 8,
 107   24 + 11 * 8,
 108   24 + 12 * 8,
 109   24 + 13 * 8,
 110   24 + 14 * 8,                  /* ... %r15 */
 111   24 + 19 * 8,                  /* %rip */
 112   24 + 21 * 8,                  /* %eflags */
 113   24 + 20 * 8,                  /* %cs */
 114   24 + 23 * 8,                  /* %ss */
 115   -1,                           /* %ds */
 116   -1,                           /* %es */
 117   -1,                           /* %fs */
 118   -1                            /* %gs */
 119 };
 120
 121 /* From /usr/src/lib/libc/amd64/gen/_setjmp.S.  */
 122 static int amd64fbsd_jmp_buf_reg_offset[] =
 123 {
 124   -1,                           /* %rax */
 125   1 * 8,                        /* %rbx */
 126   -1,                           /* %rcx */
 127   -1,                           /* %rdx */
 128   -1,                           /* %rsi */
 129   -1,                           /* %rdi */
 130   3 * 8,                        /* %rbp */
 131   2 * 8,                        /* %rsp */
 132   -1,                           /* %r8 ...  */
 133   -1,
 134   -1,
 135   -1,                           /* ... %r11 */
 136   4 * 8,                        /* %r12 ...  */
 137   5 * 8,
 138   6 * 8,
 139   7 * 8,                        /* ... %r15 */
 140   0 * 8                         /* %rip */
 141 };
 142
 143 static void
 144 amd64fbsd_supply_uthread (struct regcache *regcache,
 145                           int regnum, CORE_ADDR addr)
 146 {
 147   gdb_byte buf[8];
 148   int i;
 149
 150   gdb_assert (regnum >= -1);
 151
 152   for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
 153     {
 154       if (amd64fbsd_jmp_buf_reg_offset[i] != -1
 155           && (regnum == -1 || regnum == i))
 156         {
 157           read_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
 158           regcache_raw_supply (regcache, i, buf);
 159         }
 160     }
 161 }
 162
 163 static void
 164 amd64fbsd_collect_uthread (const struct regcache *regcache,
 165                            int regnum, CORE_ADDR addr)
 166 {
 167   gdb_byte buf[8];
 168   int i;
 169
 170   gdb_assert (regnum >= -1);
 171
 172   for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
 173     {
 174       if (amd64fbsd_jmp_buf_reg_offset[i] != -1
 175           && (regnum == -1 || regnum == i))
 176         {
 177           regcache_raw_collect (regcache, i, buf);
 178           write_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
 179         }
 180     }
 181 }
 182
 183 static void
 184 amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 185 {
 186   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 187
 188   /* Obviously FreeBSD is BSD-based.  */
 189   i386bsd_init_abi (info, gdbarch);
 190
 191   tdep->gregset_reg_offset = amd64fbsd_r_reg_offset;
 192   tdep->gregset_num_regs = ARRAY_SIZE (amd64fbsd_r_reg_offset);
 193   tdep->sizeof_gregset = 22 * 8;
 194
 195   amd64_init_abi (info, gdbarch);
 196
 197   tdep->sigtramp_start = amd64fbsd_sigtramp_start_addr;
 198   tdep->sigtramp_end = amd64fbsd_sigtramp_end_addr;
 199   tdep->sigcontext_addr = amd64fbsd_sigcontext_addr;
 200   tdep->sc_reg_offset = amd64fbsd_sc_reg_offset;
 201   tdep->sc_num_regs = ARRAY_SIZE (amd64fbsd_sc_reg_offset);
 202
 203   /* FreeBSD provides a user-level threads implementation.  */
 204   bsd_uthread_set_supply_uthread (gdbarch, amd64fbsd_supply_uthread);
 205   bsd_uthread_set_collect_uthread (gdbarch, amd64fbsd_collect_uthread);
 206
 207   /* FreeBSD uses SVR4-style shared libraries.  */
 208   set_solib_svr4_fetch_link_map_offsets
 209     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 210 }
 211 \f
 212
 213 /* Provide a prototype to silence -Wmissing-prototypes.  */
 214 void _initialize_amd64fbsd_tdep (void);
 215
 216 void
 217 _initialize_amd64fbsd_tdep (void)
 218 {
 219   gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
 220                           GDB_OSABI_FREEBSD_ELF, amd64fbsd_init_abi);
 221 }