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, 2008
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "server.h"
  22 #include "linux-low.h"
  23 #include "i387-fp.h"
  24
  25 #include "gdb_proc_service.h"
  26
  27 #include <sys/reg.h>
  28 #include <sys/procfs.h>
  29 #include <sys/ptrace.h>
  30
  31 /* This definition comes from prctl.h, but some kernels may not have it.  */
  32 #ifndef PTRACE_ARCH_PRCTL
  33 #define PTRACE_ARCH_PRCTL      30
  34 #endif
  35
  36 /* The following definitions come from prctl.h, but may be absent
  37    for certain configurations.  */
  38 #ifndef ARCH_GET_FS
  39 #define ARCH_SET_GS 0x1001
  40 #define ARCH_SET_FS 0x1002
  41 #define ARCH_GET_FS 0x1003
  42 #define ARCH_GET_GS 0x1004
  43 #endif
  44
  45 static int x86_64_regmap[] = {
  46   RAX * 8, RBX * 8, RCX * 8, RDX * 8,
  47   RSI * 8, RDI * 8, RBP * 8, RSP * 8,
  48   R8 * 8, R9 * 8, R10 * 8, R11 * 8,
  49   R12 * 8, R13 * 8, R14 * 8, R15 * 8,
  50   RIP * 8, EFLAGS * 8, CS * 8, SS * 8,
  51   DS * 8, ES * 8, FS * 8, GS * 8,
  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,
  55   -1, -1, -1, -1, -1, -1, -1, -1, -1,
  56   ORIG_RAX * 8
  57 };
  58
  59 #define X86_64_NUM_GREGS (sizeof(x86_64_regmap)/sizeof(int))
  60
  61 /* Called by libthread_db.  */
  62
  63 ps_err_e
  64 ps_get_thread_area (const struct ps_prochandle *ph,
  65                     lwpid_t lwpid, int idx, void **base)
  66 {
  67   switch (idx)
  68     {
  69     case FS:
  70       if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_FS) == 0)
  71         return PS_OK;
  72       break;
  73     case GS:
  74       if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_GS) == 0)
  75         return PS_OK;
  76       break;
  77     default:
  78       return PS_BADADDR;
  79     }
  80   return PS_ERR;
  81 }
  82
  83 static void
  84 x86_64_fill_gregset (void *buf)
  85 {
  86   int i;
  87
  88   for (i = 0; i < X86_64_NUM_GREGS; i++)
  89     if (x86_64_regmap[i] != -1)
  90       collect_register (i, ((char *) buf) + x86_64_regmap[i]);
  91 }
  92
  93 static void
  94 x86_64_store_gregset (const void *buf)
  95 {
  96   int i;
  97
  98   for (i = 0; i < X86_64_NUM_GREGS; i++)
  99     if (x86_64_regmap[i] != -1)
 100       supply_register (i, ((char *) buf) + x86_64_regmap[i]);
 101 }
 102
 103 static void
 104 x86_64_fill_fpregset (void *buf)
 105 {
 106   i387_cache_to_fxsave (buf);
 107 }
 108
 109 static void
 110 x86_64_store_fpregset (const void *buf)
 111 {
 112   i387_fxsave_to_cache (buf);
 113 }
 114
 115 struct regset_info target_regsets[] = {
 116   { PTRACE_GETREGS, PTRACE_SETREGS, sizeof (elf_gregset_t),
 117     GENERAL_REGS,
 118     x86_64_fill_gregset, x86_64_store_gregset },
 119   { PTRACE_GETFPREGS, PTRACE_SETFPREGS, sizeof (elf_fpregset_t),
 120     FP_REGS,
 121     x86_64_fill_fpregset, x86_64_store_fpregset },
 122   { 0, 0, -1, -1, NULL, NULL }
 123 };
 124
 125 static const unsigned char x86_64_breakpoint[] = { 0xCC };
 126 #define x86_64_breakpoint_len 1
 127
 128 extern int debug_threads;
 129
 130 static CORE_ADDR
 131 x86_64_get_pc ()
 132 {
 133   unsigned long pc;
 134
 135   collect_register_by_name ("rip", &pc);
 136
 137   if (debug_threads)
 138     fprintf (stderr, "stop pc (before any decrement) is %08lx\n", pc);
 139   return pc;
 140 }
 141
 142 static void
 143 x86_64_set_pc (CORE_ADDR newpc)
 144 {
 145   if (debug_threads)
 146     fprintf (stderr, "set pc to %08lx\n", (long) newpc);
 147   supply_register_by_name ("rip", &newpc);
 148 }
 149
 150 static int
 151 x86_64_breakpoint_at (CORE_ADDR pc)
 152 {
 153   unsigned char c;
 154
 155   read_inferior_memory (pc, &c, 1);
 156   if (c == 0xCC)
 157     return 1;
 158
 159   return 0;
 160 }
 161
 162 struct linux_target_ops the_low_target = {
 163   -1,
 164   NULL,
 165   NULL,
 166   NULL,
 167   x86_64_get_pc,
 168   x86_64_set_pc,
 169   x86_64_breakpoint,
 170   x86_64_breakpoint_len,
 171   NULL,
 172   1,
 173   x86_64_breakpoint_at,
 174   NULL,
 175   NULL,
 176   NULL,
 177   NULL,
 178   0,
 179   "i386:x86-64",
 180 };