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 #define private static
  59
  60 \f
  61 /* Find offsets to thread states at compile time.
  62  * If your compiler does not grok this, calculate offsets
  63  * offsets yourself and use them (or get a compatible compiler :-)
  64  */
  65
  66 #define  REG_OFFSET(reg) (int)(&((struct i386_thread_state *)0)->reg)
  67
  68 /* at reg_offset[i] is the offset to the i386_thread_state
  69  * location where the gdb registers[i] is stored.
  70  */
  71
  72 static int reg_offset[] =
  73 {
  74   REG_OFFSET(eax),  REG_OFFSET(ecx), REG_OFFSET(edx), REG_OFFSET(ebx),
  75   REG_OFFSET(uesp), REG_OFFSET(ebp), REG_OFFSET(esi), REG_OFFSET(edi),
  76   REG_OFFSET(eip),  REG_OFFSET(efl), REG_OFFSET(cs),  REG_OFFSET(ss),
  77   REG_OFFSET(ds),   REG_OFFSET(es),  REG_OFFSET(fs),  REG_OFFSET(gs)
  78 };
  79
  80 #define REG_ADDRESS(state,regnum) ((char *)(state)+reg_offset[regnum])
  81
  82 /* Fetch COUNT contiguous registers from thread STATE starting from REGNUM
  83  * Caller knows that the regs handled in one transaction are of same size.
  84  */
  85 #define FETCH_REGS(state, regnum, count) \
  86   memcpy (&registers[REGISTER_BYTE (regnum)], \
  87           REG_ADDRESS (state, regnum), \
  88           count*REGISTER_SIZE)
  89
  90 /* Store COUNT contiguous registers to thread STATE starting from REGNUM */
  91 #define STORE_REGS(state, regnum, count) \
  92   memcpy (REG_ADDRESS (state, regnum), \
  93           &registers[REGISTER_BYTE (regnum)], \
  94           count*REGISTER_SIZE)
  95 \f
  96 /*
  97  * Fetch inferiors registers for gdb.
  98  * REGNO specifies which (as gdb views it) register, -1 for all.
  99  */
 100
 101 void
 102 fetch_inferior_registers (regno)
 103      int regno;
 104 {
 105   kern_return_t ret;
 106   thread_state_data_t state;
 107   unsigned int stateCnt = i386_THREAD_STATE_COUNT;
 108   int index;
 109
 110   if (! MACH_PORT_VALID (current_thread))
 111     error ("fetch inferior registers: Invalid thread");
 112
 113   if (must_suspend_thread)
 114     setup_thread (current_thread, 1);
 115
 116   ret = thread_get_state (current_thread,
 117                           i386_THREAD_STATE,
 118                           state,
 119                           &stateCnt);
 120
 121   if (ret != KERN_SUCCESS)
 122     message ("fetch_inferior_registers: %s ",
 123              mach_error_string (ret));
 124 #if 0
 125   /* It may be more effective to store validate all of them,
 126    * since we fetched them all anyway
 127    */
 128   else if (regno != -1)
 129     supply_register (regno, (char *)state+reg_offset[regno]);
 130 #endif
 131   else
 132     {
 133       for (index = 0; index < NUM_REGS; index++)
 134         supply_register (index, (char *)state+reg_offset[index]);
 135     }
 136
 137   if (must_suspend_thread)
 138     setup_thread (current_thread, 0);
 139 }
 140 \f
 141 /* Store our register values back into the inferior.
 142  * If REGNO is -1, do this for all registers.
 143  * Otherwise, REGNO specifies which register
 144  *
 145  * On mach3 all registers are always saved in one call.
 146  */
 147 void
 148 store_inferior_registers (regno)
 149      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       message ("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     message ("store_inferior_registers (set): %s",
 202              mach_error_string (ret));
 203
 204   if (must_suspend_thread)
 205     setup_thread (current_thread, 0);
 206 }
 207
 208 \f
 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 coredep.c(fetch_core_registers)
 219  */
 220
 221 unsigned int
 222 register_addr (regno, blockend)
 223      int regno;
 224      int blockend;
 225 {
 226   unsigned int 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 (status, ep)
 263      unsigned short status;
 264      struct env387 *ep;
 265 {
 266   int i;
 267   int bothstatus;
 268   int top;
 269   int fpreg;
 270   unsigned char *p;
 271
 272   bothstatus = ((status != 0) && (ep->status != 0));
 273   if (status != 0)
 274     {
 275       if (bothstatus)
 276         printf_unfiltered ("u: ");
 277       print_387_status_word (status);
 278     }
 279
 280   if (ep->status != 0)
 281     {
 282       if (bothstatus)
 283         printf_unfiltered ("e: ");
 284       print_387_status_word (ep->status);
 285     }
 286
 287   print_387_control_word (ep->control);
 288   printf_unfiltered ("last exception: ");
 289   printf_unfiltered ("opcode %s; ", local_hex_string(ep->opcode));
 290   printf_unfiltered ("pc %s:", local_hex_string(ep->code_seg));
 291   printf_unfiltered ("%s; ", local_hex_string(ep->eip));
 292   printf_unfiltered ("operand %s", local_hex_string(ep->operand_seg));
 293   printf_unfiltered (":%s\n", local_hex_string(ep->operand));
 294
 295   top = (ep->status >> 11) & 7;
 296
 297   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 298   for (fpreg = 7; fpreg >= 0; fpreg--)
 299     {
 300       double val;
 301
 302       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 303
 304       switch ((ep->tag >> (fpreg * 2)) & 3)
 305         {
 306         case 0: printf_unfiltered ("valid "); break;
 307         case 1: printf_unfiltered ("zero  "); break;
 308         case 2: printf_unfiltered ("trap  "); break;
 309         case 3: printf_unfiltered ("empty "); break;
 310         }
 311       for (i = 9; i >= 0; i--)
 312         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 313
 314       floatformat_to_double (&floatformat_i387_ext, (char *)ep->regs[fpreg],
 315                                &val);
 316       printf_unfiltered ("  %g\n", val);
 317     }
 318   if (ep->r0)
 319     printf_unfiltered ("warning: reserved0 is %s\n", local_hex_string(ep->r0));
 320   if (ep->r1)
 321     printf_unfiltered ("warning: reserved1 is %s\n", local_hex_string(ep->r1));
 322   if (ep->r2)
 323     printf_unfiltered ("warning: reserved2 is %s\n", local_hex_string(ep->r2));
 324   if (ep->r3)
 325     printf_unfiltered ("warning: reserved3 is %s\n", local_hex_string(ep->r3));
 326 }
 327
 328 /*
 329  * values that go into fp_kind (from <i386/fpreg.h>)
 330  */
 331 #define FP_NO   0       /* no fp chip, no emulator (no fp support)      */
 332 #define FP_SW   1       /* no fp chip, using software emulator          */
 333 #define FP_HW   2       /* chip present bit                             */
 334 #define FP_287  2       /* 80287 chip present                           */
 335 #define FP_387  3       /* 80387 chip present                           */
 336
 337 typedef struct fpstate {
 338 #if 1
 339   unsigned char state[FP_STATE_BYTES]; /* "hardware" state */
 340 #else
 341   struct env387 state;  /* Actually this */
 342 #endif
 343   int status;           /* Duplicate status */
 344 } *fpstate_t;
 345
 346 /* Mach 3 specific routines.
 347  */
 348 private boolean_t
 349 get_i387_state (fstate)
 350      struct fpstate *fstate;
 351 {
 352   kern_return_t ret;
 353   thread_state_data_t state;
 354   unsigned int fsCnt = i386_FLOAT_STATE_COUNT;
 355   struct i386_float_state *fsp;
 356
 357   ret = thread_get_state (current_thread,
 358                           i386_FLOAT_STATE,
 359                           state,
 360                           &fsCnt);
 361
 362   if (ret != KERN_SUCCESS)
 363     {
 364       message ("Can not get live floating point state: %s",
 365                mach_error_string (ret));
 366       return FALSE;
 367     }
 368
 369   fsp = (struct i386_float_state *)state;
 370   /* The 387 chip (also 486 counts) or a software emulator? */
 371   if (!fsp->initialized || (fsp->fpkind != FP_387 && fsp->fpkind != FP_SW))
 372     return FALSE;
 373
 374   /* Clear the target then copy thread's float state there.
 375      Make a copy of the status word, for some reason?
 376    */
 377   bzero (fstate, sizeof(struct fpstate));
 378
 379   fstate->status = fsp->exc_status;
 380
 381   memcpy (fstate->state, (char *)&fsp->hw_state, FP_STATE_BYTES);
 382
 383   return TRUE;
 384 }
 385
 386 private boolean_t
 387 get_i387_core_state (fstate)
 388      struct fpstate *fstate;
 389 {
 390   /* Not implemented yet. Core files do not contain float state. */
 391   return FALSE;
 392 }
 393
 394 /*
 395  * This is called by "info float" command
 396  */
 397 void
 398 i386_mach3_float_info()
 399 {
 400   char buf [sizeof (struct fpstate) + 2 * sizeof (int)];
 401   boolean_t valid = FALSE;
 402   fpstate_t fps;
 403
 404   if (target_has_execution)
 405     valid = get_i387_state (buf);
 406 #if 0
 407   else if (WE HAVE CORE FILE)  /* @@@@ Core files not supported */
 408     valid = get_i387_core_state (buf);
 409 #endif
 410
 411   if (!valid)
 412     {
 413       message("no floating point status saved");
 414       return;
 415     }
 416
 417   fps = (fpstate_t) buf;
 418
 419   print_387_status (fps->status, (struct env387 *)fps->state);
 420 }