gdb/i386m3-nat.c

   1 /* Low level interface to I386 running mach 3.0.
   2    Copyright 1992, 1993, 1994, 1996, 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 <stdio.h>
  28
  29 #include <mach.h>
  30 #include <mach/message.h>
  31 #include <mach/exception.h>
  32 #include <mach_error.h>
  33
  34 /* Hmmm... Should this not be here?
  35  * Now for i386_float_info() target_has_execution
  36  */
  37 #include <target.h>
  38
  39 /* This mess is duplicated in bfd/i386mach3.h
  40
  41  * This is an ugly way to hack around the incorrect
  42  * definition of UPAGES in i386/machparam.h.
  43  *
  44  * The definition should specify the size reserved
  45  * for "struct user" in core files in PAGES,
  46  * but instead it gives it in 512-byte core-clicks
  47  * for i386 and i860.
  48  */
  49 #include <sys/param.h>
  50 #if UPAGES == 16
  51 #define UAREA_SIZE ctob(UPAGES)
  52 #elif UPAGES == 2
  53 #define UAREA_SIZE (NBPG*UPAGES)
  54 #else
  55 FIXME ! !UPAGES is neither 2 nor 16
  56 #endif
  57
  58 /* @@@ Should move print_387_status() to i387-tdep.c */
  59 extern void print_387_control_word ();          /* i387-tdep.h */
  60 extern void print_387_status_word ();
  61
  62 #define private static
  63 \f
  64
  65 /* Find offsets to thread states at compile time.
  66  * If your compiler does not grok this, calculate offsets
  67  * offsets yourself and use them (or get a compatible compiler :-)
  68  */
  69
  70 #define  REG_OFFSET(reg) (int)(&((struct i386_thread_state *)0)->reg)
  71
  72 /* at reg_offset[i] is the offset to the i386_thread_state
  73  * location where the gdb registers[i] is stored.
  74  */
  75
  76 static int reg_offset[] =
  77 {
  78   REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx),
  79   REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi),
  80   REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss),
  81   REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs)
  82 };
  83
  84 #define REG_ADDRESS(state,regnum) ((char *)(state)+reg_offset[regnum])
  85
  86 /* Fetch COUNT contiguous registers from thread STATE starting from REGNUM
  87  * Caller knows that the regs handled in one transaction are of same size.
  88  */
  89 #define FETCH_REGS(state, regnum, count) \
  90   memcpy (&registers[REGISTER_BYTE (regnum)], \
  91           REG_ADDRESS (state, regnum), \
  92           count*REGISTER_SIZE)
  93
  94 /* Store COUNT contiguous registers to thread STATE starting from REGNUM */
  95 #define STORE_REGS(state, regnum, count) \
  96   memcpy (REG_ADDRESS (state, regnum), \
  97           &registers[REGISTER_BYTE (regnum)], \
  98           count*REGISTER_SIZE)
  99 \f
 100 /*
 101  * Fetch inferiors registers for gdb.
 102  * REGNO specifies which (as gdb views it) register, -1 for all.
 103  */
 104
 105 void
 106 fetch_inferior_registers (int regno)
 107 {
 108   kern_return_t ret;
 109   thread_state_data_t state;
 110   unsigned int stateCnt = i386_THREAD_STATE_COUNT;
 111   int index;
 112
 113   if (!MACH_PORT_VALID (current_thread))
 114     error ("fetch inferior registers: Invalid thread");
 115
 116   if (must_suspend_thread)
 117     setup_thread (current_thread, 1);
 118
 119   ret = thread_get_state (current_thread,
 120                           i386_THREAD_STATE,
 121                           state,
 122                           &stateCnt);
 123
 124   if (ret != KERN_SUCCESS)
 125     warning ("fetch_inferior_registers: %s ",
 126              mach_error_string (ret));
 127 #if 0
 128   /* It may be more effective to store validate all of them,
 129    * since we fetched them all anyway
 130    */
 131   else if (regno != -1)
 132     supply_register (regno, (char *) state + reg_offset[regno]);
 133 #endif
 134   else
 135     {
 136       for (index = 0; index < NUM_REGS; index++)
 137         supply_register (index, (char *) state + reg_offset[index]);
 138     }
 139
 140   if (must_suspend_thread)
 141     setup_thread (current_thread, 0);
 142 }
 143 \f
 144 /* Store our register values back into the inferior.
 145  * If REGNO is -1, do this for all registers.
 146  * Otherwise, REGNO specifies which register
 147  *
 148  * On mach3 all registers are always saved in one call.
 149  */
 150 void
 151 store_inferior_registers (int regno)
 152 {
 153   kern_return_t ret;
 154   thread_state_data_t state;
 155   unsigned int stateCnt = i386_THREAD_STATE_COUNT;
 156   register int index;
 157
 158   if (!MACH_PORT_VALID (current_thread))
 159     error ("store inferior registers: Invalid thread");
 160
 161   if (must_suspend_thread)
 162     setup_thread (current_thread, 1);
 163
 164   /* Fetch the state of the current thread */
 165   ret = thread_get_state (current_thread,
 166                           i386_THREAD_STATE,
 167                           state,
 168                           &stateCnt);
 169
 170   if (ret != KERN_SUCCESS)
 171     {
 172       warning ("store_inferior_registers (get): %s",
 173                mach_error_string (ret));
 174       if (must_suspend_thread)
 175         setup_thread (current_thread, 0);
 176       return;
 177     }
 178
 179   /* move gdb's registers to thread's state
 180
 181    * Since we save all registers anyway, save the ones
 182    * that gdb thinks are valid (e.g. ignore the regno
 183    * parameter)
 184    */
 185 #if 0
 186   if (regno != -1)
 187     STORE_REGS (state, regno, 1);
 188   else
 189 #endif
 190     {
 191       for (index = 0; index < NUM_REGS; index++)
 192         STORE_REGS (state, index, 1);
 193     }
 194
 195   /* Write gdb's current view of register to the thread
 196    */
 197   ret = thread_set_state (current_thread,
 198                           i386_THREAD_STATE,
 199                           state,
 200                           i386_THREAD_STATE_COUNT);
 201
 202   if (ret != KERN_SUCCESS)
 203     warning ("store_inferior_registers (set): %s",
 204              mach_error_string (ret));
 205
 206   if (must_suspend_thread)
 207     setup_thread (current_thread, 0);
 208 }
 209 \f
 210
 211
 212 /* Return the address in the core dump or inferior of register REGNO.
 213  * BLOCKEND should be the address of the end of the UPAGES area read
 214  * in memory, but it's not?
 215  *
 216  * Currently our UX server dumps the whole thread state to the
 217  * core file. If your UX does something else, adapt the routine
 218  * below to return the offset to the given register.
 219  *
 220  * Called by core-aout.c(fetch_core_registers)
 221  */
 222
 223 CORE_ADDR
 224 register_addr (int regno, CORE_ADDR blockend)
 225 {
 226   CORE_ADDR addr;
 227
 228   if (regno < 0 || regno >= NUM_REGS)
 229     error ("Invalid register number %d.", regno);
 230
 231   /* UAREA_SIZE == 8 kB in i386 */
 232   addr = (unsigned int) REG_ADDRESS (UAREA_SIZE - sizeof (struct i386_thread_state), regno);
 233
 234   return addr;
 235 }
 236
 237 /* jtv@hut.fi: I copied and modified this 387 code from
 238  * gdb/i386-xdep.c. Modifications for Mach 3.0.
 239  *
 240  * i387 status dumper. See also i387-tdep.c
 241  */
 242 struct env387
 243 {
 244   unsigned short control;
 245   unsigned short r0;
 246   unsigned short status;
 247   unsigned short r1;
 248   unsigned short tag;
 249   unsigned short r2;
 250   unsigned long eip;
 251   unsigned short code_seg;
 252   unsigned short opcode;
 253   unsigned long operand;
 254   unsigned short operand_seg;
 255   unsigned short r3;
 256   unsigned char regs[8][10];
 257 };
 258 /* This routine is machine independent?
 259  * Should move it to i387-tdep.c but you need to export struct env387
 260  */
 261 private
 262 print_387_status (unsigned short status, struct env387 *ep)
 263 {
 264   int i;
 265   int bothstatus;
 266   int top;
 267   int fpreg;
 268   unsigned char *p;
 269
 270   bothstatus = ((status != 0) && (ep->status != 0));
 271   if (status != 0)
 272     {
 273       if (bothstatus)
 274         printf_unfiltered ("u: ");
 275       print_387_status_word (status);
 276     }
 277
 278   if (ep->status != 0)
 279     {
 280       if (bothstatus)
 281         printf_unfiltered ("e: ");
 282       print_387_status_word (ep->status);
 283     }
 284
 285   print_387_control_word (ep->control);
 286   printf_unfiltered ("last exception: ");
 287   printf_unfiltered ("opcode %s; ", local_hex_string (ep->opcode));
 288   printf_unfiltered ("pc %s:", local_hex_string (ep->code_seg));
 289   printf_unfiltered ("%s; ", local_hex_string (ep->eip));
 290   printf_unfiltered ("operand %s", local_hex_string (ep->operand_seg));
 291   printf_unfiltered (":%s\n", local_hex_string (ep->operand));
 292
 293   top = (ep->status >> 11) & 7;
 294
 295   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 296   for (fpreg = 7; fpreg >= 0; fpreg--)
 297     {
 298       double val;
 299
 300       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 301
 302       switch ((ep->tag >> (fpreg * 2)) & 3)
 303         {
 304         case 0:
 305           printf_unfiltered ("valid ");
 306           break;
 307         case 1:
 308           printf_unfiltered ("zero  ");
 309           break;
 310         case 2:
 311           printf_unfiltered ("trap  ");
 312           break;
 313         case 3:
 314           printf_unfiltered ("empty ");
 315           break;
 316         }
 317       for (i = 9; i >= 0; i--)
 318         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 319
 320       floatformat_to_double (&floatformat_i387_ext, (char *) ep->regs[fpreg],
 321                              &val);
 322       printf_unfiltered ("  %g\n", val);
 323     }
 324   if (ep->r0)
 325     printf_unfiltered ("warning: reserved0 is %s\n", local_hex_string (ep->r0));
 326   if (ep->r1)
 327     printf_unfiltered ("warning: reserved1 is %s\n", local_hex_string (ep->r1));
 328   if (ep->r2)
 329     printf_unfiltered ("warning: reserved2 is %s\n", local_hex_string (ep->r2));
 330   if (ep->r3)
 331     printf_unfiltered ("warning: reserved3 is %s\n", local_hex_string (ep->r3));
 332 }
 333
 334 /*
 335  * values that go into fp_kind (from <i386/fpreg.h>)
 336  */
 337 #define FP_NO   0               /* no fp chip, no emulator (no fp support)      */
 338 #define FP_SW   1               /* no fp chip, using software emulator          */
 339 #define FP_HW   2               /* chip present bit                             */
 340 #define FP_287  2               /* 80287 chip present                           */
 341 #define FP_387  3               /* 80387 chip present                           */
 342
 343 typedef struct fpstate
 344 {
 345 #if 1
 346   unsigned char state[FP_STATE_BYTES];  /* "hardware" state */
 347 #else
 348   struct env387 state;          /* Actually this */
 349 #endif
 350   int status;                   /* Duplicate status */
 351 }
 352  *fpstate_t;
 353
 354 /* Mach 3 specific routines.
 355  */
 356 private boolean_t
 357 get_i387_state (struct fpstate *fstate)
 358 {
 359   kern_return_t ret;
 360   thread_state_data_t state;
 361   unsigned int fsCnt = i386_FLOAT_STATE_COUNT;
 362   struct i386_float_state *fsp;
 363
 364   ret = thread_get_state (current_thread,
 365                           i386_FLOAT_STATE,
 366                           state,
 367                           &fsCnt);
 368
 369   if (ret != KERN_SUCCESS)
 370     {
 371       warning ("Can not get live floating point state: %s",
 372                mach_error_string (ret));
 373       return FALSE;
 374     }
 375
 376   fsp = (struct i386_float_state *) state;
 377   /* The 387 chip (also 486 counts) or a software emulator? */
 378   if (!fsp->initialized || (fsp->fpkind != FP_387 && fsp->fpkind != FP_SW))
 379     return FALSE;
 380
 381   /* Clear the target then copy thread's float state there.
 382      Make a copy of the status word, for some reason?
 383    */
 384   memset (fstate, 0, sizeof (struct fpstate));
 385
 386   fstate->status = fsp->exc_status;
 387
 388   memcpy (fstate->state, (char *) &fsp->hw_state, FP_STATE_BYTES);
 389
 390   return TRUE;
 391 }
 392
 393 private boolean_t
 394 get_i387_core_state (struct fpstate *fstate)
 395 {
 396   /* Not implemented yet. Core files do not contain float state. */
 397   return FALSE;
 398 }
 399
 400 /*
 401  * This is called by "info float" command
 402  */
 403 void
 404 i386_mach3_float_info (void)
 405 {
 406   char buf[sizeof (struct fpstate) + 2 * sizeof (int)];
 407   boolean_t valid = FALSE;
 408   fpstate_t fps;
 409
 410   if (target_has_execution)
 411     valid = get_i387_state (buf);
 412 #if 0
 413   else if (WE HAVE CORE FILE)   /* @@@@ Core files not supported */
 414     valid = get_i387_core_state (buf);
 415 #endif
 416
 417   if (!valid)
 418     {
 419       warning ("no floating point status saved");
 420       return;
 421     }
 422
 423   fps = (fpstate_t) buf;
 424
 425   print_387_status (fps->status, (struct env387 *) fps->state);
 426 }