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 "i386-tdep.h"
  37
  38 #include "gnu-nat.h"
  39 #include "i387-tdep.h"
  40
  41 #ifdef HAVE_SYS_PROCFS_H
  42 # include <sys/procfs.h>
  43 # include "gregset.h"
  44 #endif
  45
  46 /* Offset to the thread_state_t location where REG is stored.  */
  47 #define REG_OFFSET(reg) offsetof (struct i386_thread_state, reg)
  48
  49 /* At REG_OFFSET[N] is the offset to the thread_state_t location where
  50    the GDB register N is stored.  */
  51 static int reg_offset[] =
  52 {
  53   REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx),
  54   REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi),
  55   REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss),
  56   REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs)
  57 };
  58
  59 #define REG_ADDR(state, regnum) ((char *)(state) + reg_offset[regnum])
  60
  61 \f
  62 /* Get the whole floating-point state of THREAD and record the
  63    values of the corresponding (pseudo) registers.  */
  64 static void
  65 fetch_fpregs (struct proc *thread)
  66 {
  67   mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT;
  68   struct i386_float_state state;
  69   error_t err;
  70
  71   err = thread_get_state (thread->port, i386_FLOAT_STATE,
  72                           (thread_state_t) &state, &count);
  73   if (err)
  74     {
  75       warning ("Couldn't fetch floating-point state from %s",
  76                proc_string (thread));
  77       return;
  78     }
  79
  80   if (!state.initialized)
  81     /* The floating-point state isn't initialized.  */
  82     {
  83       int i;
  84
  85       for (i = FP0_REGNUM; i <= FOP_REGNUM; i++)
  86         supply_register (i, NULL);
  87
  88       return;
  89     }
  90
  91   /* Supply the floating-point registers.  */
  92   i387_supply_fsave (state.hw_state);
  93 }
  94
  95 #ifdef HAVE_SYS_PROCFS_H
  96 /* These two calls are used by the core-regset.c code for
  97    reading ELF core files.  */
  98 void
  99 supply_gregset (gdb_gregset_t *gregs)
 100 {
 101   int i;
 102   for (i = 0; i < NUM_GREGS; i++)
 103     supply_register (i, REG_ADDR (gregs, i));
 104 }
 105
 106 void
 107 supply_fpregset (gdb_fpregset_t *fpregs)
 108 {
 109   i387_supply_fsave ((char *) fpregs);
 110 }
 111 #endif
 112
 113 /* Fetch register REGNO, or all regs if REGNO is -1.  */
 114 void
 115 gnu_fetch_registers (int regno)
 116 {
 117   struct proc *thread;
 118
 119   /* Make sure we know about new threads.  */
 120   inf_update_procs (current_inferior);
 121
 122   thread = inf_tid_to_thread (current_inferior, PIDGET (inferior_ptid));
 123   if (!thread)
 124     error ("Can't fetch registers from thread %d: No such thread",
 125            PIDGET (inferior_ptid));
 126
 127   if (regno < NUM_GREGS || regno == -1)
 128     {
 129       thread_state_t state;
 130
 131       /* This does the dirty work for us.  */
 132       state = proc_get_state (thread, 0);
 133       if (!state)
 134         {
 135           warning ("Couldn't fetch registers from %s",
 136                    proc_string (thread));
 137           return;
 138         }
 139
 140       if (regno == -1)
 141         {
 142           int i;
 143
 144           proc_debug (thread, "fetching all register");
 145
 146           for (i = 0; i < NUM_GREGS; i++)
 147             supply_register (i, REG_ADDR (state, i));
 148           thread->fetched_regs = ~0;
 149         }
 150       else
 151         {
 152           proc_debug (thread, "fetching register %s", REGISTER_NAME (regno));
 153
 154           supply_register (regno, REG_ADDR (state, regno));
 155           thread->fetched_regs |= (1 << regno);
 156         }
 157     }
 158
 159   if (regno >= NUM_GREGS || regno == -1)
 160     {
 161       proc_debug (thread, "fetching floating-point registers");
 162
 163       fetch_fpregs (thread);
 164     }
 165 }
 166 \f
 167
 168 /* Store the whole floating-point state into THREAD using information
 169    from the corresponding (pseudo) registers.  */
 170 static void
 171 store_fpregs (struct proc *thread, int regno)
 172 {
 173   mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT;
 174   struct i386_float_state state;
 175   error_t err;
 176
 177   err = thread_get_state (thread->port, i386_FLOAT_STATE,
 178                           (thread_state_t) &state, &count);
 179   if (err)
 180     {
 181       warning ("Couldn't fetch floating-point state from %s",
 182                proc_string (thread));
 183       return;
 184     }
 185
 186   /* FIXME: kettenis/2001-07-15: Is this right?  Should we somehow
 187      take into account REGISTER_VALID like the old code did?  */
 188   i387_fill_fsave (state.hw_state, regno);
 189
 190   err = thread_set_state (thread->port, i386_FLOAT_STATE,
 191                           (thread_state_t) &state, i386_FLOAT_STATE_COUNT);
 192   if (err)
 193     {
 194       warning ("Couldn't store floating-point state into %s",
 195                proc_string (thread));
 196       return;
 197     }
 198 }
 199
 200 /* Store at least register REGNO, or all regs if REGNO == -1.  */
 201 void
 202 gnu_store_registers (int regno)
 203 {
 204   struct proc *thread;
 205
 206   /* Make sure we know about new threads.  */
 207   inf_update_procs (current_inferior);
 208
 209   thread = inf_tid_to_thread (current_inferior, PIDGET (inferior_ptid));
 210   if (!thread)
 211     error ("Couldn't store registers into thread %d: No such thread",
 212            PIDGET (inferior_ptid));
 213
 214   if (regno < NUM_GREGS || regno == -1)
 215     {
 216       thread_state_t state;
 217       thread_state_data_t old_state;
 218       int was_aborted = thread->aborted;
 219       int was_valid = thread->state_valid;
 220       int trace;
 221
 222       if (!was_aborted && was_valid)
 223         memcpy (&old_state, &thread->state, sizeof (old_state));
 224
 225       state = proc_get_state (thread, 1);
 226       if (!state)
 227         {
 228           warning ("Couldn't store registers into %s", proc_string (thread));
 229           return;
 230         }
 231
 232       /* Save the T bit.  We might try to restore the %eflags register
 233          below, but changing the T bit would seriously confuse GDB.  */
 234       trace = ((struct i386_thread_state *)state)->efl & 0x100;
 235
 236       if (!was_aborted && was_valid)
 237         /* See which registers have changed after aborting the thread.  */
 238         {
 239           int check_regno;
 240
 241           for (check_regno = 0; check_regno < NUM_GREGS; check_regno++)
 242             if ((thread->fetched_regs & (1 << check_regno))
 243                 && memcpy (REG_ADDR (&old_state, check_regno),
 244                            REG_ADDR (state, check_regno),
 245                            REGISTER_RAW_SIZE (check_regno)))
 246               /* Register CHECK_REGNO has changed!  Ack!  */
 247               {
 248                 warning ("Register %s changed after the thread was aborted",
 249                          REGISTER_NAME (check_regno));
 250                 if (regno >= 0 && regno != check_regno)
 251                   /* Update GDB's copy of the register.  */
 252                   supply_register (check_regno, REG_ADDR (state, check_regno));
 253                 else
 254                   warning ("... also writing this register!  Suspicious...");
 255               }
 256         }
 257
 258 #define fill(state, regno)                                               \
 259   memcpy (REG_ADDR(state, regno), &registers[REGISTER_BYTE (regno)],     \
 260           REGISTER_RAW_SIZE (regno))
 261
 262       if (regno == -1)
 263         {
 264           int i;
 265
 266           proc_debug (thread, "storing all registers");
 267
 268           for (i = 0; i < NUM_GREGS; i++)
 269             if (register_valid[i])
 270               fill (state, i);
 271         }
 272       else
 273         {
 274           proc_debug (thread, "storing register %s", REGISTER_NAME (regno));
 275
 276           gdb_assert (register_valid[regno]);
 277           fill (state, regno);
 278         }
 279
 280       /* Restore the T bit.  */
 281       ((struct i386_thread_state *)state)->efl &= ~0x100;
 282       ((struct i386_thread_state *)state)->efl |= trace;
 283     }
 284
 285 #undef fill
 286
 287   if (regno >= NUM_GREGS || regno == -1)
 288     {
 289       proc_debug (thread, "storing floating-point registers");
 290
 291       store_fpregs (thread, regno);
 292     }
 293 }