gdb/i386gnu-nat.c

   1 /* Low level interface to i386 running the GNU Hurd.
   2    Copyright 1992, 1995, 1996, 1998, 2000, 2001
   3    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., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "inferior.h"
  24 #include "floatformat.h"
  25 #include "regcache.h"
  26
  27 #include "gdb_assert.h"
  28 #include <errno.h>
  29 #include <stdio.h>
  30
  31 #include <mach.h>
  32 #include <mach_error.h>
  33 #include <mach/message.h>
  34 #include <mach/exception.h>
  35
  36 #include "gnu-nat.h"
  37 #include "i387-nat.h"
  38
  39
  40 /* Offset to the thread_state_t location where REG is stored.  */
  41 #define REG_OFFSET(reg) offsetof (struct i386_thread_state, reg)
  42
  43 /* At REG_OFFSET[N] is the offset to the thread_state_t location where
  44    the GDB register N is stored.  */
  45 static int reg_offset[] =
  46 {
  47   REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx),
  48   REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi),
  49   REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss),
  50   REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs)
  51 };
  52
  53 #define REG_ADDR(state, regnum) ((char *)(state) + reg_offset[regnum])
  54
  55 \f
  56 /* Get the whole floating-point state of THREAD and record the
  57    values of the corresponding (pseudo) registers.  */
  58 static void
  59 fetch_fpregs (struct proc *thread)
  60 {
  61   mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT;
  62   struct i386_float_state state;
  63   error_t err;
  64
  65   err = thread_get_state (thread->port, i386_FLOAT_STATE,
  66                           (thread_state_t) &state, &count);
  67   if (err)
  68     {
  69       warning ("Couldn't fetch floating-point state from %s",
  70                proc_string (thread));
  71       return;
  72     }
  73
  74   if (!state.initialized)
  75     /* The floating-point state isn't initialized.  */
  76     {
  77       int i;
  78
  79       for (i = FP0_REGNUM; i <= FP7_REGNUM; i++)
  80         supply_register (i, NULL);
  81       for (i = FCTRL_REGNUM; i <= FOP_REGNUM; i++)
  82         supply_register (i, NULL);
  83
  84       return;
  85     }
  86
  87   /* Supply the floating-point registers.  */
  88   i387_supply_fsave (state.hw_state);
  89 }
  90
  91 /* Fetch register REGNO, or all regs if REGNO is -1.  */
  92 void
  93 gnu_fetch_registers (int regno)
  94 {
  95   struct proc *thread;
  96
  97   /* Make sure we know about new threads.  */
  98   inf_update_procs (current_inferior);
  99
 100   thread = inf_tid_to_thread (current_inferior, PIDGET (inferior_ptid));
 101   if (!thread)
 102     error ("Can't fetch registers from thread %d: No such thread",
 103            PIDGET (inferior_ptid));
 104
 105   if (regno < NUM_GREGS || regno == -1)
 106     {
 107       thread_state_t state;
 108
 109       /* This does the dirty work for us.  */
 110       state = proc_get_state (thread, 0);
 111       if (!state)
 112         {
 113           warning ("Couldn't fetch registers from %s",
 114                    proc_string (thread));
 115           return;
 116         }
 117
 118       if (regno == -1)
 119         {
 120           int i;
 121
 122           proc_debug (thread, "fetching all register");
 123
 124           for (i = 0; i < NUM_GREGS; i++)
 125             supply_register (i, REG_ADDR (state, i));
 126           thread->fetched_regs = ~0;
 127         }
 128       else
 129         {
 130           proc_debug (thread, "fetching register %s", REGISTER_NAME (regno));
 131
 132           supply_register (regno, REG_ADDR (state, regno));
 133           thread->fetched_regs |= (1 << regno);
 134         }
 135     }
 136
 137   if (regno >= NUM_GREGS || regno == -1)
 138     {
 139       proc_debug (thread, "fetching floating-point registers");
 140
 141       fetch_fpregs (thread);
 142     }
 143 }
 144 \f
 145
 146 /* Store the whole floating-point state into THREAD using information
 147    from the corresponding (pseudo) registers.  */
 148 static void
 149 store_fpregs (struct proc *thread, int regno)
 150 {
 151   mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT;
 152   struct i386_float_state state;
 153   error_t err;
 154
 155   err = thread_get_state (thread->port, i386_FLOAT_STATE,
 156                           (thread_state_t) &state, &count);
 157   if (err)
 158     {
 159       warning ("Couldn't fetch floating-point state from %s",
 160                proc_string (thread));
 161       return;
 162     }
 163
 164   /* FIXME: kettenis/2001-07-15: Is this right?  Should we somehow
 165      take into account REGISTER_VALID like the old code did?  */
 166   i387_fill_fsave (state.hw_state, regno);
 167
 168   err = thread_set_state (thread->port, i386_FLOAT_STATE,
 169                           (thread_state_t) &state, i386_FLOAT_STATE_COUNT);
 170   if (err)
 171     {
 172       warning ("Couldn't store floating-point state into %s",
 173                proc_string (thread));
 174       return;
 175     }
 176 }
 177
 178 /* Store at least register REGNO, or all regs if REGNO == -1.  */
 179 void
 180 gnu_store_registers (int regno)
 181 {
 182   struct proc *thread;
 183
 184   /* Make sure we know about new threads.  */
 185   inf_update_procs (current_inferior);
 186
 187   thread = inf_tid_to_thread (current_inferior, PIDGET (inferior_ptid));
 188   if (!thread)
 189     error ("Couldn't store registers into thread %d: No such thread",
 190            PIDGET (inferior_ptid));
 191
 192   if (regno < NUM_GREGS || regno == -1)
 193     {
 194       thread_state_t state;
 195       thread_state_data_t old_state;
 196       int was_aborted = thread->aborted;
 197       int was_valid = thread->state_valid;
 198       int trace;
 199
 200       if (!was_aborted && was_valid)
 201         memcpy (&old_state, &thread->state, sizeof (old_state));
 202
 203       state = proc_get_state (thread, 1);
 204       if (!state)
 205         {
 206           warning ("Couldn't store registers into %s", proc_string (thread));
 207           return;
 208         }
 209
 210       /* Save the T bit.  We might try to restore the %eflags register
 211          below, but changing the T bit would seriously confuse GDB.  */
 212       trace = ((struct i386_thread_state *)state)->efl & 0x100;
 213
 214       if (!was_aborted && was_valid)
 215         /* See which registers have changed after aborting the thread.  */
 216         {
 217           int check_regno;
 218
 219           for (check_regno = 0; check_regno < NUM_GREGS; check_regno++)
 220             if ((thread->fetched_regs & (1 << check_regno))
 221                 && memcpy (REG_ADDR (&old_state, check_regno),
 222                            REG_ADDR (state, check_regno),
 223                            REGISTER_RAW_SIZE (check_regno)))
 224               /* Register CHECK_REGNO has changed!  Ack!  */
 225               {
 226                 warning ("Register %s changed after the thread was aborted",
 227                          REGISTER_NAME (check_regno));
 228                 if (regno >= 0 && regno != check_regno)
 229                   /* Update GDB's copy of the register.  */
 230                   supply_register (check_regno, REG_ADDR (state, check_regno));
 231                 else
 232                   warning ("... also writing this register!  Suspicious...");
 233               }
 234         }
 235
 236 #define fill(state, regno)                                               \
 237   memcpy (REG_ADDR(state, regno), &registers[REGISTER_BYTE (regno)],     \
 238           REGISTER_RAW_SIZE (regno))
 239
 240       if (regno == -1)
 241         {
 242           int i;
 243
 244           proc_debug (thread, "storing all registers");
 245
 246           for (i = 0; i < NUM_GREGS; i++)
 247             if (register_valid[i])
 248               fill (state, i);
 249         }
 250       else
 251         {
 252           proc_debug (thread, "storing register %s", REGISTER_NAME (regno));
 253
 254           gdb_assert (register_valid[regno]);
 255           fill (state, regno);
 256         }
 257
 258       /* Restore the T bit.  */
 259       ((struct i386_thread_state *)state)->efl &= ~0x100;
 260       ((struct i386_thread_state *)state)->efl |= trace;
 261     }
 262
 263 #undef fill
 264
 265   if (regno >= NUM_GREGS || regno == -1)
 266     {
 267       proc_debug (thread, "storing floating-point registers");
 268
 269       store_fpregs (thread, regno);
 270     }
 271 }