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