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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "defs.h"
  21 #include "inferior.h"
  22
  23 #include <stdio.h>
  24
  25 #include <mach.h>
  26 #include <mach/message.h>
  27 #include <mach/exception.h>
  28 #include <mach_error.h>
  29
  30 /* Hmmm... Should this not be here?
  31  * Now for i386_float_info() target_has_execution
  32  */
  33 #include <target.h>
  34
  35 /* This mess is duplicated in bfd/i386mach3.h
  36  *
  37  * This is an ugly way to hack around the incorrect
  38  * definition of UPAGES in i386/machparam.h.
  39  *
  40  * The definition should specify the size reserved
  41  * for "struct user" in core files in PAGES,
  42  * but instead it gives it in 512-byte core-clicks
  43  * for i386 and i860.
  44  */
  45 #include <sys/param.h>
  46 #if UPAGES == 16
  47 #define UAREA_SIZE ctob(UPAGES)
  48 #elif UPAGES == 2
  49 #define UAREA_SIZE (NBPG*UPAGES)
  50 #else
  51 FIXME!! UPAGES is neither 2 nor 16
  52 #endif
  53
  54 /* @@@ Should move print_387_status() to i387-tdep.c */
  55 extern void print_387_control_word ();          /* i387-tdep.h */
  56 extern void print_387_status_word ();
  57
  58 extern struct ext_format ext_format_i387;
  59
  60 #define private static
  61
  62 \f
  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*sizeof (REGISTER_TYPE))
  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*sizeof (REGISTER_TYPE))
  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 (regno)
 105      int regno;
 106 {
 107   kern_return_t ret;
 108   thread_state_data_t state;
 109   unsigned int stateCnt = i386_THREAD_STATE_COUNT;
 110   int index;
 111
 112   if (! MACH_PORT_VALID (current_thread))
 113     error ("fetch inferior registers: Invalid thread");
 114
 115   if (must_suspend_thread)
 116     setup_thread (current_thread, 1);
 117
 118   ret = thread_get_state (current_thread,
 119                           i386_THREAD_STATE,
 120                           state,
 121                           &stateCnt);
 122
 123   if (ret != KERN_SUCCESS)
 124     message ("fetch_inferior_registers: %s ",
 125              mach_error_string (ret));
 126 #if 0
 127   /* It may be more effective to store validate all of them,
 128    * since we fetched them all anyway
 129    */
 130   else if (regno != -1)
 131     supply_register (regno, (char *)state+reg_offset[regno]);
 132 #endif
 133   else
 134     {
 135       for (index = 0; index < NUM_REGS; index++)
 136         supply_register (index, (char *)state+reg_offset[index]);
 137     }
 138
 139   if (must_suspend_thread)
 140     setup_thread (current_thread, 0);
 141 }
 142 \f
 143 /* Store our register values back into the inferior.
 144  * If REGNO is -1, do this for all registers.
 145  * Otherwise, REGNO specifies which register
 146  *
 147  * On mach3 all registers are always saved in one call.
 148  */
 149 void
 150 store_inferior_registers (regno)
 151      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       message ("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     message ("store_inferior_registers (set): %s",
 204              mach_error_string (ret));
 205
 206   if (must_suspend_thread)
 207     setup_thread (current_thread, 0);
 208 }
 209
 210 \f
 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 coredep.c(fetch_core_registers)
 221  */
 222
 223 unsigned int
 224 register_addr (regno, blockend)
 225      int regno;
 226      int blockend;
 227 {
 228   unsigned int addr;
 229
 230   if (regno < 0 || regno >= NUM_REGS)
 231     error ("Invalid register number %d.", regno);
 232
 233   /* UAREA_SIZE == 8 kB in i386 */
 234   addr = (unsigned int)REG_ADDRESS (UAREA_SIZE - sizeof(struct i386_thread_state), regno);
 235
 236   return addr;
 237 }
 238
 239 /* jtv@hut.fi: I copied and modified this 387 code from
 240  * gdb/i386-xdep.c. Modifications for Mach 3.0.
 241  *
 242  * i387 status dumper. See also i387-tdep.c
 243  */
 244 struct env387
 245 {
 246   unsigned short control;
 247   unsigned short r0;
 248   unsigned short status;
 249   unsigned short r1;
 250   unsigned short tag;
 251   unsigned short r2;
 252   unsigned long eip;
 253   unsigned short code_seg;
 254   unsigned short opcode;
 255   unsigned long operand;
 256   unsigned short operand_seg;
 257   unsigned short r3;
 258   unsigned char regs[8][10];
 259 };
 260 /* This routine is machine independent?
 261  * Should move it to i387-tdep.c but you need to export struct env387
 262  */
 263 private
 264 print_387_status (status, ep)
 265      unsigned short status;
 266      struct env387 *ep;
 267 {
 268   int i;
 269   int bothstatus;
 270   int top;
 271   int fpreg;
 272   unsigned char *p;
 273
 274   bothstatus = ((status != 0) && (ep->status != 0));
 275   if (status != 0)
 276     {
 277       if (bothstatus)
 278         printf_unfiltered ("u: ");
 279       print_387_status_word (status);
 280     }
 281
 282   if (ep->status != 0)
 283     {
 284       if (bothstatus)
 285         printf_unfiltered ("e: ");
 286       print_387_status_word (ep->status);
 287     }
 288
 289   print_387_control_word (ep->control);
 290   printf_unfiltered ("last exception: ");
 291   printf_unfiltered ("opcode %s; ", local_hex_string(ep->opcode));
 292   printf_unfiltered ("pc %s:", local_hex_string(ep->code_seg));
 293   printf_unfiltered ("%s; ", local_hex_string(ep->eip));
 294   printf_unfiltered ("operand %s", local_hex_string(ep->operand_seg));
 295   printf_unfiltered (":%s\n", local_hex_string(ep->operand));
 296
 297   top = (ep->status >> 11) & 7;
 298
 299   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 300   for (fpreg = 7; fpreg >= 0; fpreg--)
 301     {
 302       double val;
 303
 304       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 305
 306       switch ((ep->tag >> (fpreg * 2)) & 3)
 307         {
 308         case 0: printf_unfiltered ("valid "); break;
 309         case 1: printf_unfiltered ("zero  "); break;
 310         case 2: printf_unfiltered ("trap  "); break;
 311         case 3: printf_unfiltered ("empty "); break;
 312         }
 313       for (i = 9; i >= 0; i--)
 314         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 315
 316       ieee_extended_to_double (&ext_format_i387, (char *)ep->regs[fpreg],
 317                                &val);
 318       printf_unfiltered ("  %g\n", val);
 319     }
 320   if (ep->r0)
 321     printf_unfiltered ("warning: reserved0 is %s\n", local_hex_string(ep->r0));
 322   if (ep->r1)
 323     printf_unfiltered ("warning: reserved1 is %s\n", local_hex_string(ep->r1));
 324   if (ep->r2)
 325     printf_unfiltered ("warning: reserved2 is %s\n", local_hex_string(ep->r2));
 326   if (ep->r3)
 327     printf_unfiltered ("warning: reserved3 is %s\n", local_hex_string(ep->r3));
 328 }
 329
 330 /*
 331  * values that go into fp_kind (from <i386/fpreg.h>)
 332  */
 333 #define FP_NO   0       /* no fp chip, no emulator (no fp support)      */
 334 #define FP_SW   1       /* no fp chip, using software emulator          */
 335 #define FP_HW   2       /* chip present bit                             */
 336 #define FP_287  2       /* 80287 chip present                           */
 337 #define FP_387  3       /* 80387 chip present                           */
 338
 339 typedef struct fpstate {
 340 #if 1
 341   unsigned char state[FP_STATE_BYTES]; /* "hardware" state */
 342 #else
 343   struct env387 state;  /* Actually this */
 344 #endif
 345   int status;           /* Duplicate status */
 346 } *fpstate_t;
 347
 348 /* Mach 3 specific routines.
 349  */
 350 private boolean_t
 351 get_i387_state (fstate)
 352      struct fpstate *fstate;
 353 {
 354   kern_return_t ret;
 355   thread_state_data_t state;
 356   unsigned int fsCnt = i386_FLOAT_STATE_COUNT;
 357   struct i386_float_state *fsp;
 358
 359   ret = thread_get_state (current_thread,
 360                           i386_FLOAT_STATE,
 361                           state,
 362                           &fsCnt);
 363
 364   if (ret != KERN_SUCCESS)
 365     {
 366       message ("Can not get live floating point state: %s",
 367                mach_error_string (ret));
 368       return FALSE;
 369     }
 370
 371   fsp = (struct i386_float_state *)state;
 372   /* The 387 chip (also 486 counts) or a software emulator? */
 373   if (!fsp->initialized || (fsp->fpkind != FP_387 && fsp->fpkind != FP_SW))
 374     return FALSE;
 375
 376   /* Clear the target then copy thread's float state there.
 377      Make a copy of the status word, for some reason?
 378    */
 379   bzero (fstate, sizeof(struct fpstate));
 380
 381   fstate->status = fsp->exc_status;
 382
 383   memcpy (fstate->state, (char *)&fsp->hw_state, FP_STATE_BYTES);
 384
 385   return TRUE;
 386 }
 387
 388 private boolean_t
 389 get_i387_core_state (fstate)
 390      struct fpstate *fstate;
 391 {
 392   /* Not implemented yet. Core files do not contain float state. */
 393   return FALSE;
 394 }
 395
 396 /*
 397  * This is called by "info float" command
 398  */
 399 void
 400 i386_mach3_float_info()
 401 {
 402   char buf [sizeof (struct fpstate) + 2 * sizeof (int)];
 403   boolean_t valid = FALSE;
 404   fpstate_t fps;
 405
 406   if (target_has_execution)
 407     valid = get_i387_state (buf);
 408 #if 0
 409   else if (WE HAVE CORE FILE)  /* @@@@ Core files not supported */
 410     valid = get_i387_core_state (buf);
 411 #endif
 412
 413   if (!valid)
 414     {
 415       message("no floating point status saved");
 416       return;
 417     }
 418
 419   fps = (fpstate_t) buf;
 420
 421   print_387_status (fps->status, (struct env387 *)fps->state);
 422 }