gdb/gdbserver/linux-x86-64-low.c

   1 /* GNU/Linux/x86-64 specific low level interface, for the remote server
   2    for GDB.
   3    Copyright (C) 2002, 2004, 2005, 2006, 2007 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., 51 Franklin Street, Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 #include "server.h"
  23 #include "linux-low.h"
  24 #include "i387-fp.h"
  25
  26 #include "gdb_proc_service.h"
  27
  28 #include <sys/reg.h>
  29 #include <sys/procfs.h>
  30 #include <sys/ptrace.h>
  31
  32 /* This definition comes from prctl.h, but some kernels may not have it.  */
  33 #ifndef PTRACE_ARCH_PRCTL
  34 #define PTRACE_ARCH_PRCTL      30
  35 #endif
  36
  37 /* The following definitions come from prctl.h, but may be absent
  38    for certain configurations.  */
  39 #ifndef ARCH_GET_FS
  40 #define ARCH_SET_GS 0x1001
  41 #define ARCH_SET_FS 0x1002
  42 #define ARCH_GET_FS 0x1003
  43 #define ARCH_GET_GS 0x1004
  44 #endif
  45
  46 static int x86_64_regmap[] = {
  47   RAX * 8, RBX * 8, RCX * 8, RDX * 8,
  48   RSI * 8, RDI * 8, RBP * 8, RSP * 8,
  49   R8 * 8, R9 * 8, R10 * 8, R11 * 8,
  50   R12 * 8, R13 * 8, R14 * 8, R15 * 8,
  51   RIP * 8, EFLAGS * 8, CS * 8, SS * 8,
  52   DS * 8, ES * 8, FS * 8, GS * 8,
  53   -1, -1, -1, -1, -1, -1, -1, -1,
  54   -1, -1, -1, -1, -1, -1, -1, -1,
  55   -1, -1, -1, -1, -1, -1, -1, -1,
  56   -1, -1, -1, -1, -1, -1, -1, -1, -1,
  57   ORIG_RAX * 8
  58 };
  59
  60 #define X86_64_NUM_GREGS (sizeof(x86_64_regmap)/sizeof(int))
  61
  62 /* Called by libthread_db.  */
  63
  64 ps_err_e
  65 ps_get_thread_area (const struct ps_prochandle *ph,
  66                     lwpid_t lwpid, int idx, void **base)
  67 {
  68   switch (idx)
  69     {
  70     case FS:
  71       if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_FS) == 0)
  72         return PS_OK;
  73       break;
  74     case GS:
  75       if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_GS) == 0)
  76         return PS_OK;
  77       break;
  78     default:
  79       return PS_BADADDR;
  80     }
  81   return PS_ERR;
  82 }
  83
  84 static void
  85 x86_64_fill_gregset (void *buf)
  86 {
  87   int i;
  88
  89   for (i = 0; i < X86_64_NUM_GREGS; i++)
  90     if (x86_64_regmap[i] != -1)
  91       collect_register (i, ((char *) buf) + x86_64_regmap[i]);
  92 }
  93
  94 static void
  95 x86_64_store_gregset (const void *buf)
  96 {
  97   int i;
  98
  99   for (i = 0; i < X86_64_NUM_GREGS; i++)
 100     if (x86_64_regmap[i] != -1)
 101       supply_register (i, ((char *) buf) + x86_64_regmap[i]);
 102 }
 103
 104 static void
 105 x86_64_fill_fpregset (void *buf)
 106 {
 107   i387_cache_to_fxsave (buf);
 108 }
 109
 110 static void
 111 x86_64_store_fpregset (const void *buf)
 112 {
 113   i387_fxsave_to_cache (buf);
 114 }
 115
 116 struct regset_info target_regsets[] = {
 117   { PTRACE_GETREGS, PTRACE_SETREGS, sizeof (elf_gregset_t),
 118     GENERAL_REGS,
 119     x86_64_fill_gregset, x86_64_store_gregset },
 120   { PTRACE_GETFPREGS, PTRACE_SETFPREGS, sizeof (elf_fpregset_t),
 121     FP_REGS,
 122     x86_64_fill_fpregset, x86_64_store_fpregset },
 123   { 0, 0, -1, -1, NULL, NULL }
 124 };
 125
 126 static const unsigned char x86_64_breakpoint[] = { 0xCC };
 127 #define x86_64_breakpoint_len 1
 128
 129 extern int debug_threads;
 130
 131 static CORE_ADDR
 132 x86_64_get_pc ()
 133 {
 134   unsigned long pc;
 135
 136   collect_register_by_name ("rip", &pc);
 137
 138   if (debug_threads)
 139     fprintf (stderr, "stop pc (before any decrement) is %08lx\n", pc);
 140   return pc;
 141 }
 142
 143 static void
 144 x86_64_set_pc (CORE_ADDR newpc)
 145 {
 146   if (debug_threads)
 147     fprintf (stderr, "set pc to %08lx\n", (long) newpc);
 148   supply_register_by_name ("rip", &newpc);
 149 }
 150
 151 static int
 152 x86_64_breakpoint_at (CORE_ADDR pc)
 153 {
 154   unsigned char c;
 155
 156   read_inferior_memory (pc, &c, 1);
 157   if (c == 0xCC)
 158     return 1;
 159
 160   return 0;
 161 }
 162
 163 struct linux_target_ops the_low_target = {
 164   -1,
 165   NULL,
 166   NULL,
 167   NULL,
 168   x86_64_get_pc,
 169   x86_64_set_pc,
 170   x86_64_breakpoint,
 171   x86_64_breakpoint_len,
 172   NULL,
 173   1,
 174   x86_64_breakpoint_at,
 175   NULL,
 176   NULL,
 177   NULL,
 178   NULL,
 179   0,
 180   "i386:x86-64",
 181 };