gdb/amd64fbsd-tdep.c

   1 /* Target-dependent code for FreeBSD/amd64.
   2
   3    Copyright (C) 2003-2015 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 "fbsd-tdep.h"
  30 #include "solib-svr4.h"
  31
  32 /* Support for signal handlers.  */
  33
  34 /* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
  35    address of the associated sigcontext structure.  */
  36
  37 static CORE_ADDR
  38 amd64fbsd_sigcontext_addr (struct frame_info *this_frame)
  39 {
  40   CORE_ADDR sp;
  41
  42   /* The `struct sigcontext' (which really is an `ucontext_t' on
  43      FreeBSD/amd64) lives at a fixed offset in the signal frame.  See
  44      <machine/sigframe.h>.  */
  45   sp = frame_unwind_register_unsigned (this_frame, AMD64_RSP_REGNUM);
  46   return sp + 16;
  47 }
  48 \f
  49 /* FreeBSD 5.1-RELEASE or later.  */
  50
  51 /* Mapping between the general-purpose registers in `struct reg'
  52    format and GDB's register cache layout.
  53
  54    Note that some registers are 32-bit, but since we're little-endian
  55    we get away with that.  */
  56
  57 /* From <machine/reg.h>.  */
  58 static int amd64fbsd_r_reg_offset[] =
  59 {
  60   14 * 8,                       /* %rax */
  61   11 * 8,                       /* %rbx */
  62   13 * 8,                       /* %rcx */
  63   12 * 8,                       /* %rdx */
  64   9 * 8,                        /* %rsi */
  65   8 * 8,                        /* %rdi */
  66   10 * 8,                       /* %rbp */
  67   20 * 8,                       /* %rsp */
  68   7 * 8,                        /* %r8 ...  */
  69   6 * 8,
  70   5 * 8,
  71   4 * 8,
  72   3 * 8,
  73   2 * 8,
  74   1 * 8,
  75   0 * 8,                        /* ... %r15 */
  76   17 * 8,                       /* %rip */
  77   19 * 8,                       /* %eflags */
  78   18 * 8,                       /* %cs */
  79   21 * 8,                       /* %ss */
  80   -1,                           /* %ds */
  81   -1,                           /* %es */
  82   -1,                           /* %fs */
  83   -1                            /* %gs */
  84 };
  85
  86 /* Location of the signal trampoline.  */
  87 CORE_ADDR amd64fbsd_sigtramp_start_addr = 0x7fffffffffc0ULL;
  88 CORE_ADDR amd64fbsd_sigtramp_end_addr = 0x7fffffffffe0ULL;
  89
  90 /* From <machine/signal.h>.  */
  91 int amd64fbsd_sc_reg_offset[] =
  92 {
  93   24 + 6 * 8,                   /* %rax */
  94   24 + 7 * 8,                   /* %rbx */
  95   24 + 3 * 8,                   /* %rcx */
  96   24 + 2 * 8,                   /* %rdx */
  97   24 + 1 * 8,                   /* %rsi */
  98   24 + 0 * 8,                   /* %rdi */
  99   24 + 8 * 8,                   /* %rbp */
 100   24 + 22 * 8,                  /* %rsp */
 101   24 + 4 * 8,                   /* %r8 ...  */
 102   24 + 5 * 8,
 103   24 + 9 * 8,
 104   24 + 10 * 8,
 105   24 + 11 * 8,
 106   24 + 12 * 8,
 107   24 + 13 * 8,
 108   24 + 14 * 8,                  /* ... %r15 */
 109   24 + 19 * 8,                  /* %rip */
 110   24 + 21 * 8,                  /* %eflags */
 111   24 + 20 * 8,                  /* %cs */
 112   24 + 23 * 8,                  /* %ss */
 113   -1,                           /* %ds */
 114   -1,                           /* %es */
 115   -1,                           /* %fs */
 116   -1                            /* %gs */
 117 };
 118
 119 /* From /usr/src/lib/libc/amd64/gen/_setjmp.S.  */
 120 static int amd64fbsd_jmp_buf_reg_offset[] =
 121 {
 122   -1,                           /* %rax */
 123   1 * 8,                        /* %rbx */
 124   -1,                           /* %rcx */
 125   -1,                           /* %rdx */
 126   -1,                           /* %rsi */
 127   -1,                           /* %rdi */
 128   3 * 8,                        /* %rbp */
 129   2 * 8,                        /* %rsp */
 130   -1,                           /* %r8 ...  */
 131   -1,
 132   -1,
 133   -1,                           /* ... %r11 */
 134   4 * 8,                        /* %r12 ...  */
 135   5 * 8,
 136   6 * 8,
 137   7 * 8,                        /* ... %r15 */
 138   0 * 8                         /* %rip */
 139 };
 140
 141 static void
 142 amd64fbsd_supply_uthread (struct regcache *regcache,
 143                           int regnum, CORE_ADDR addr)
 144 {
 145   gdb_byte buf[8];
 146   int i;
 147
 148   gdb_assert (regnum >= -1);
 149
 150   for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
 151     {
 152       if (amd64fbsd_jmp_buf_reg_offset[i] != -1
 153           && (regnum == -1 || regnum == i))
 154         {
 155           read_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
 156           regcache_raw_supply (regcache, i, buf);
 157         }
 158     }
 159 }
 160
 161 static void
 162 amd64fbsd_collect_uthread (const struct regcache *regcache,
 163                            int regnum, CORE_ADDR addr)
 164 {
 165   gdb_byte buf[8];
 166   int i;
 167
 168   gdb_assert (regnum >= -1);
 169
 170   for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
 171     {
 172       if (amd64fbsd_jmp_buf_reg_offset[i] != -1
 173           && (regnum == -1 || regnum == i))
 174         {
 175           regcache_raw_collect (regcache, i, buf);
 176           write_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
 177         }
 178     }
 179 }
 180
 181 static void
 182 amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 183 {
 184   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 185
 186   /* Generic FreeBSD support. */
 187   fbsd_init_abi (info, gdbarch);
 188
 189   /* Obviously FreeBSD is BSD-based.  */
 190   i386bsd_init_abi (info, gdbarch);
 191
 192   tdep->gregset_reg_offset = amd64fbsd_r_reg_offset;
 193   tdep->gregset_num_regs = ARRAY_SIZE (amd64fbsd_r_reg_offset);
 194   tdep->sizeof_gregset = 22 * 8;
 195
 196   amd64_init_abi (info, gdbarch);
 197
 198   tdep->sigtramp_start = amd64fbsd_sigtramp_start_addr;
 199   tdep->sigtramp_end = amd64fbsd_sigtramp_end_addr;
 200   tdep->sigcontext_addr = amd64fbsd_sigcontext_addr;
 201   tdep->sc_reg_offset = amd64fbsd_sc_reg_offset;
 202   tdep->sc_num_regs = ARRAY_SIZE (amd64fbsd_sc_reg_offset);
 203
 204   /* FreeBSD provides a user-level threads implementation.  */
 205   bsd_uthread_set_supply_uthread (gdbarch, amd64fbsd_supply_uthread);
 206   bsd_uthread_set_collect_uthread (gdbarch, amd64fbsd_collect_uthread);
 207
 208   /* FreeBSD uses SVR4-style shared libraries.  */
 209   set_solib_svr4_fetch_link_map_offsets
 210     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 211 }
 212 \f
 213
 214 /* Provide a prototype to silence -Wmissing-prototypes.  */
 215 void _initialize_amd64fbsd_tdep (void);
 216
 217 void
 218 _initialize_amd64fbsd_tdep (void)
 219 {
 220   gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
 221                           GDB_OSABI_FREEBSD_ELF, amd64fbsd_init_abi);
 222 }