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