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 (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     warning ("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       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 (regno, blockend)
 225      int regno;
 226      CORE_ADDR blockend;
 227 {
 228   CORE_ADDR 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:
 309           printf_unfiltered ("valid ");
 310           break;
 311         case 1:
 312           printf_unfiltered ("zero  ");
 313           break;
 314         case 2:
 315           printf_unfiltered ("trap  ");
 316           break;
 317         case 3:
 318           printf_unfiltered ("empty ");
 319           break;
 320         }
 321       for (i = 9; i >= 0; i--)
 322         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 323
 324       floatformat_to_double (&floatformat_i387_ext, (char *) ep->regs[fpreg],
 325                              &val);
 326       printf_unfiltered ("  %g\n", val);
 327     }
 328   if (ep->r0)
 329     printf_unfiltered ("warning: reserved0 is %s\n", local_hex_string (ep->r0));
 330   if (ep->r1)
 331     printf_unfiltered ("warning: reserved1 is %s\n", local_hex_string (ep->r1));
 332   if (ep->r2)
 333     printf_unfiltered ("warning: reserved2 is %s\n", local_hex_string (ep->r2));
 334   if (ep->r3)
 335     printf_unfiltered ("warning: reserved3 is %s\n", local_hex_string (ep->r3));
 336 }
 337
 338 /*
 339  * values that go into fp_kind (from <i386/fpreg.h>)
 340  */
 341 #define FP_NO   0               /* no fp chip, no emulator (no fp support)      */
 342 #define FP_SW   1               /* no fp chip, using software emulator          */
 343 #define FP_HW   2               /* chip present bit                             */
 344 #define FP_287  2               /* 80287 chip present                           */
 345 #define FP_387  3               /* 80387 chip present                           */
 346
 347 typedef struct fpstate
 348 {
 349 #if 1
 350   unsigned char state[FP_STATE_BYTES];  /* "hardware" state */
 351 #else
 352   struct env387 state;          /* Actually this */
 353 #endif
 354   int status;                   /* Duplicate status */
 355 }
 356  *fpstate_t;
 357
 358 /* Mach 3 specific routines.
 359  */
 360 private boolean_t
 361 get_i387_state (fstate)
 362      struct fpstate *fstate;
 363 {
 364   kern_return_t ret;
 365   thread_state_data_t state;
 366   unsigned int fsCnt = i386_FLOAT_STATE_COUNT;
 367   struct i386_float_state *fsp;
 368
 369   ret = thread_get_state (current_thread,
 370                           i386_FLOAT_STATE,
 371                           state,
 372                           &fsCnt);
 373
 374   if (ret != KERN_SUCCESS)
 375     {
 376       warning ("Can not get live floating point state: %s",
 377                mach_error_string (ret));
 378       return FALSE;
 379     }
 380
 381   fsp = (struct i386_float_state *) state;
 382   /* The 387 chip (also 486 counts) or a software emulator? */
 383   if (!fsp->initialized || (fsp->fpkind != FP_387 && fsp->fpkind != FP_SW))
 384     return FALSE;
 385
 386   /* Clear the target then copy thread's float state there.
 387      Make a copy of the status word, for some reason?
 388    */
 389   memset (fstate, 0, sizeof (struct fpstate));
 390
 391   fstate->status = fsp->exc_status;
 392
 393   memcpy (fstate->state, (char *) &fsp->hw_state, FP_STATE_BYTES);
 394
 395   return TRUE;
 396 }
 397
 398 private boolean_t
 399 get_i387_core_state (fstate)
 400      struct fpstate *fstate;
 401 {
 402   /* Not implemented yet. Core files do not contain float state. */
 403   return FALSE;
 404 }
 405
 406 /*
 407  * This is called by "info float" command
 408  */
 409 void
 410 i386_mach3_float_info ()
 411 {
 412   char buf[sizeof (struct fpstate) + 2 * sizeof (int)];
 413   boolean_t valid = FALSE;
 414   fpstate_t fps;
 415
 416   if (target_has_execution)
 417     valid = get_i387_state (buf);
 418 #if 0
 419   else if (WE HAVE CORE FILE)   /* @@@@ Core files not supported */
 420     valid = get_i387_core_state (buf);
 421 #endif
 422
 423   if (!valid)
 424     {
 425       warning ("no floating point status saved");
 426       return;
 427     }
 428
 429   fps = (fpstate_t) buf;
 430
 431   print_387_status (fps->status, (struct env387 *) fps->state);
 432 }