gdb/i386m3-nat.c

   1 /* Low level interface to I386 running mach 3.0.
   2    Copyright (C) 1992 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include "inferior.h"
  23 #include "floatformat.h"
  24
  25 #include <stdio.h>
  26
  27 #include <mach.h>
  28 #include <mach/message.h>
  29 #include <mach/exception.h>
  30 #include <mach_error.h>
  31
  32 /* Hmmm... Should this not be here?
  33  * Now for i386_float_info() target_has_execution
  34  */
  35 #include <target.h>
  36
  37 /* This mess is duplicated in bfd/i386mach3.h
  38
  39  * This is an ugly way to hack around the incorrect
  40  * definition of UPAGES in i386/machparam.h.
  41  *
  42  * The definition should specify the size reserved
  43  * for "struct user" in core files in PAGES,
  44  * but instead it gives it in 512-byte core-clicks
  45  * for i386 and i860.
  46  */
  47 #include <sys/param.h>
  48 #if UPAGES == 16
  49 #define UAREA_SIZE ctob(UPAGES)
  50 #elif UPAGES == 2
  51 #define UAREA_SIZE (NBPG*UPAGES)
  52 #else
  53 FIXME ! !UPAGES is neither 2 nor 16
  54 #endif
  55
  56 /* @@@ Should move print_387_status() to i387-tdep.c */
  57 extern void print_387_control_word ();          /* i387-tdep.h */
  58 extern void print_387_status_word ();
  59
  60 #define private static
  61 \f
  62
  63 /* Find offsets to thread states at compile time.
  64  * If your compiler does not grok this, calculate offsets
  65  * offsets yourself and use them (or get a compatible compiler :-)
  66  */
  67
  68 #define  REG_OFFSET(reg) (int)(&((struct i386_thread_state *)0)->reg)
  69
  70 /* at reg_offset[i] is the offset to the i386_thread_state
  71  * location where the gdb registers[i] is stored.
  72  */
  73
  74 static int reg_offset[] =
  75 {
  76   REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx),
  77   REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi),
  78   REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss),
  79   REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs)
  80 };
  81
  82 #define REG_ADDRESS(state,regnum) ((char *)(state)+reg_offset[regnum])
  83
  84 /* Fetch COUNT contiguous registers from thread STATE starting from REGNUM
  85  * Caller knows that the regs handled in one transaction are of same size.
  86  */
  87 #define FETCH_REGS(state, regnum, count) \
  88   memcpy (&registers[REGISTER_BYTE (regnum)], \
  89           REG_ADDRESS (state, regnum), \
  90           count*REGISTER_SIZE)
  91
  92 /* Store COUNT contiguous registers to thread STATE starting from REGNUM */
  93 #define STORE_REGS(state, regnum, count) \
  94   memcpy (REG_ADDRESS (state, regnum), \
  95           &registers[REGISTER_BYTE (regnum)], \
  96           count*REGISTER_SIZE)
  97 \f
  98 /*
  99  * Fetch inferiors registers for gdb.
 100  * REGNO specifies which (as gdb views it) register, -1 for all.
 101  */
 102
 103 void
 104 fetch_inferior_registers (int regno)
 105 {
 106   kern_return_t ret;
 107   thread_state_data_t state;
 108   unsigned int stateCnt = i386_THREAD_STATE_COUNT;
 109   int index;
 110
 111   if (!MACH_PORT_VALID (current_thread))
 112     error ("fetch inferior registers: Invalid thread");
 113
 114   if (must_suspend_thread)
 115     setup_thread (current_thread, 1);
 116
 117   ret = thread_get_state (current_thread,
 118                           i386_THREAD_STATE,
 119                           state,
 120                           &stateCnt);
 121
 122   if (ret != KERN_SUCCESS)
 123     warning ("fetch_inferior_registers: %s ",
 124              mach_error_string (ret));
 125 #if 0
 126   /* It may be more effective to store validate all of them,
 127    * since we fetched them all anyway
 128    */
 129   else if (regno != -1)
 130     supply_register (regno, (char *) state + reg_offset[regno]);
 131 #endif
 132   else
 133     {
 134       for (index = 0; index < NUM_REGS; index++)
 135         supply_register (index, (char *) state + reg_offset[index]);
 136     }
 137
 138   if (must_suspend_thread)
 139     setup_thread (current_thread, 0);
 140 }
 141 \f
 142 /* Store our register values back into the inferior.
 143  * If REGNO is -1, do this for all registers.
 144  * Otherwise, REGNO specifies which register
 145  *
 146  * On mach3 all registers are always saved in one call.
 147  */
 148 void
 149 store_inferior_registers (int regno)
 150 {
 151   kern_return_t ret;
 152   thread_state_data_t state;
 153   unsigned int stateCnt = i386_THREAD_STATE_COUNT;
 154   register int index;
 155
 156   if (!MACH_PORT_VALID (current_thread))
 157     error ("store inferior registers: Invalid thread");
 158
 159   if (must_suspend_thread)
 160     setup_thread (current_thread, 1);
 161
 162   /* Fetch the state of the current thread */
 163   ret = thread_get_state (current_thread,
 164                           i386_THREAD_STATE,
 165                           state,
 166                           &stateCnt);
 167
 168   if (ret != KERN_SUCCESS)
 169     {
 170       warning ("store_inferior_registers (get): %s",
 171                mach_error_string (ret));
 172       if (must_suspend_thread)
 173         setup_thread (current_thread, 0);
 174       return;
 175     }
 176
 177   /* move gdb's registers to thread's state
 178
 179    * Since we save all registers anyway, save the ones
 180    * that gdb thinks are valid (e.g. ignore the regno
 181    * parameter)
 182    */
 183 #if 0
 184   if (regno != -1)
 185     STORE_REGS (state, regno, 1);
 186   else
 187 #endif
 188     {
 189       for (index = 0; index < NUM_REGS; index++)
 190         STORE_REGS (state, index, 1);
 191     }
 192
 193   /* Write gdb's current view of register to the thread
 194    */
 195   ret = thread_set_state (current_thread,
 196                           i386_THREAD_STATE,
 197                           state,
 198                           i386_THREAD_STATE_COUNT);
 199
 200   if (ret != KERN_SUCCESS)
 201     warning ("store_inferior_registers (set): %s",
 202              mach_error_string (ret));
 203
 204   if (must_suspend_thread)
 205     setup_thread (current_thread, 0);
 206 }
 207 \f
 208
 209
 210 /* Return the address in the core dump or inferior of register REGNO.
 211  * BLOCKEND should be the address of the end of the UPAGES area read
 212  * in memory, but it's not?
 213  *
 214  * Currently our UX server dumps the whole thread state to the
 215  * core file. If your UX does something else, adapt the routine
 216  * below to return the offset to the given register.
 217  *
 218  * Called by core-aout.c(fetch_core_registers)
 219  */
 220
 221 CORE_ADDR
 222 register_addr (int regno, CORE_ADDR blockend)
 223 {
 224   CORE_ADDR addr;
 225
 226   if (regno < 0 || regno >= NUM_REGS)
 227     error ("Invalid register number %d.", regno);
 228
 229   /* UAREA_SIZE == 8 kB in i386 */
 230   addr = (unsigned int) REG_ADDRESS (UAREA_SIZE - sizeof (struct i386_thread_state), regno);
 231
 232   return addr;
 233 }
 234
 235 /* jtv@hut.fi: I copied and modified this 387 code from
 236  * gdb/i386-xdep.c. Modifications for Mach 3.0.
 237  *
 238  * i387 status dumper. See also i387-tdep.c
 239  */
 240 struct env387
 241 {
 242   unsigned short control;
 243   unsigned short r0;
 244   unsigned short status;
 245   unsigned short r1;
 246   unsigned short tag;
 247   unsigned short r2;
 248   unsigned long eip;
 249   unsigned short code_seg;
 250   unsigned short opcode;
 251   unsigned long operand;
 252   unsigned short operand_seg;
 253   unsigned short r3;
 254   unsigned char regs[8][10];
 255 };
 256 /* This routine is machine independent?
 257  * Should move it to i387-tdep.c but you need to export struct env387
 258  */
 259 private
 260 print_387_status (unsigned short status, struct env387 *ep)
 261 {
 262   int i;
 263   int bothstatus;
 264   int top;
 265   int fpreg;
 266   unsigned char *p;
 267
 268   bothstatus = ((status != 0) && (ep->status != 0));
 269   if (status != 0)
 270     {
 271       if (bothstatus)
 272         printf_unfiltered ("u: ");
 273       print_387_status_word (status);
 274     }
 275
 276   if (ep->status != 0)
 277     {
 278       if (bothstatus)
 279         printf_unfiltered ("e: ");
 280       print_387_status_word (ep->status);
 281     }
 282
 283   print_387_control_word (ep->control);
 284   printf_unfiltered ("last exception: ");
 285   printf_unfiltered ("opcode %s; ", local_hex_string (ep->opcode));
 286   printf_unfiltered ("pc %s:", local_hex_string (ep->code_seg));
 287   printf_unfiltered ("%s; ", local_hex_string (ep->eip));
 288   printf_unfiltered ("operand %s", local_hex_string (ep->operand_seg));
 289   printf_unfiltered (":%s\n", local_hex_string (ep->operand));
 290
 291   top = (ep->status >> 11) & 7;
 292
 293   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 294   for (fpreg = 7; fpreg >= 0; fpreg--)
 295     {
 296       double val;
 297
 298       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 299
 300       switch ((ep->tag >> (fpreg * 2)) & 3)
 301         {
 302         case 0:
 303           printf_unfiltered ("valid ");
 304           break;
 305         case 1:
 306           printf_unfiltered ("zero  ");
 307           break;
 308         case 2:
 309           printf_unfiltered ("trap  ");
 310           break;
 311         case 3:
 312           printf_unfiltered ("empty ");
 313           break;
 314         }
 315       for (i = 9; i >= 0; i--)
 316         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 317
 318       floatformat_to_double (&floatformat_i387_ext, (char *) ep->regs[fpreg],
 319                              &val);
 320       printf_unfiltered ("  %g\n", val);
 321     }
 322   if (ep->r0)
 323     printf_unfiltered ("warning: reserved0 is %s\n", local_hex_string (ep->r0));
 324   if (ep->r1)
 325     printf_unfiltered ("warning: reserved1 is %s\n", local_hex_string (ep->r1));
 326   if (ep->r2)
 327     printf_unfiltered ("warning: reserved2 is %s\n", local_hex_string (ep->r2));
 328   if (ep->r3)
 329     printf_unfiltered ("warning: reserved3 is %s\n", local_hex_string (ep->r3));
 330 }
 331
 332 /*
 333  * values that go into fp_kind (from <i386/fpreg.h>)
 334  */
 335 #define FP_NO   0               /* no fp chip, no emulator (no fp support)      */
 336 #define FP_SW   1               /* no fp chip, using software emulator          */
 337 #define FP_HW   2               /* chip present bit                             */
 338 #define FP_287  2               /* 80287 chip present                           */
 339 #define FP_387  3               /* 80387 chip present                           */
 340
 341 typedef struct fpstate
 342 {
 343 #if 1
 344   unsigned char state[FP_STATE_BYTES];  /* "hardware" state */
 345 #else
 346   struct env387 state;          /* Actually this */
 347 #endif
 348   int status;                   /* Duplicate status */
 349 }
 350  *fpstate_t;
 351
 352 /* Mach 3 specific routines.
 353  */
 354 private boolean_t
 355 get_i387_state (struct fpstate *fstate)
 356 {
 357   kern_return_t ret;
 358   thread_state_data_t state;
 359   unsigned int fsCnt = i386_FLOAT_STATE_COUNT;
 360   struct i386_float_state *fsp;
 361
 362   ret = thread_get_state (current_thread,
 363                           i386_FLOAT_STATE,
 364                           state,
 365                           &fsCnt);
 366
 367   if (ret != KERN_SUCCESS)
 368     {
 369       warning ("Can not get live floating point state: %s",
 370                mach_error_string (ret));
 371       return FALSE;
 372     }
 373
 374   fsp = (struct i386_float_state *) state;
 375   /* The 387 chip (also 486 counts) or a software emulator? */
 376   if (!fsp->initialized || (fsp->fpkind != FP_387 && fsp->fpkind != FP_SW))
 377     return FALSE;
 378
 379   /* Clear the target then copy thread's float state there.
 380      Make a copy of the status word, for some reason?
 381    */
 382   memset (fstate, 0, sizeof (struct fpstate));
 383
 384   fstate->status = fsp->exc_status;
 385
 386   memcpy (fstate->state, (char *) &fsp->hw_state, FP_STATE_BYTES);
 387
 388   return TRUE;
 389 }
 390
 391 private boolean_t
 392 get_i387_core_state (struct fpstate *fstate)
 393 {
 394   /* Not implemented yet. Core files do not contain float state. */
 395   return FALSE;
 396 }
 397
 398 /*
 399  * This is called by "info float" command
 400  */
 401 void
 402 i386_mach3_float_info (void)
 403 {
 404   char buf[sizeof (struct fpstate) + 2 * sizeof (int)];
 405   boolean_t valid = FALSE;
 406   fpstate_t fps;
 407
 408   if (target_has_execution)
 409     valid = get_i387_state (buf);
 410 #if 0
 411   else if (WE HAVE CORE FILE)   /* @@@@ Core files not supported */
 412     valid = get_i387_core_state (buf);
 413 #endif
 414
 415   if (!valid)
 416     {
 417       warning ("no floating point status saved");
 418       return;
 419     }
 420
 421   fps = (fpstate_t) buf;
 422
 423   print_387_status (fps->status, (struct env387 *) fps->state);
 424 }