gdb/i386m3-nat.c

   1 /* Low level interface to I386 running mach 3.0.
   2    Copyright 1992, 2001 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 #include "regcache.h"
  25
  26 #include <stdio.h>
  27
  28 #include <mach.h>
  29 #include <mach/message.h>
  30 #include <mach/exception.h>
  31 #include <mach_error.h>
  32
  33 /* Hmmm... Should this not be here?
  34  * Now for i386_float_info() target_has_execution
  35  */
  36 #include <target.h>
  37
  38 /* This mess is duplicated in bfd/i386mach3.h
  39
  40  * This is an ugly way to hack around the incorrect
  41  * definition of UPAGES in i386/machparam.h.
  42  *
  43  * The definition should specify the size reserved
  44  * for "struct user" in core files in PAGES,
  45  * but instead it gives it in 512-byte core-clicks
  46  * for i386 and i860.
  47  */
  48 #include <sys/param.h>
  49 #if UPAGES == 16
  50 #define UAREA_SIZE ctob(UPAGES)
  51 #elif UPAGES == 2
  52 #define UAREA_SIZE (NBPG*UPAGES)
  53 #else
  54 FIXME ! !UPAGES is neither 2 nor 16
  55 #endif
  56
  57 /* @@@ Should move print_387_status() to i387-tdep.c */
  58 extern void print_387_control_word ();          /* i387-tdep.h */
  59 extern void print_387_status_word ();
  60
  61 #define private static
  62 \f
  63
  64 /* Find offsets to thread states at compile time.
  65  * If your compiler does not grok this, calculate offsets
  66  * offsets yourself and use them (or get a compatible compiler :-)
  67  */
  68
  69 #define  REG_OFFSET(reg) (int)(&((struct i386_thread_state *)0)->reg)
  70
  71 /* at reg_offset[i] is the offset to the i386_thread_state
  72  * location where the gdb registers[i] is stored.
  73  */
  74
  75 static int reg_offset[] =
  76 {
  77   REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx),
  78   REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi),
  79   REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss),
  80   REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs)
  81 };
  82
  83 #define REG_ADDRESS(state,regnum) ((char *)(state)+reg_offset[regnum])
  84
  85 /* Fetch COUNT contiguous registers from thread STATE starting from REGNUM
  86  * Caller knows that the regs handled in one transaction are of same size.
  87  */
  88 #define FETCH_REGS(state, regnum, count) \
  89   memcpy (&registers[REGISTER_BYTE (regnum)], \
  90           REG_ADDRESS (state, regnum), \
  91           count*REGISTER_SIZE)
  92
  93 /* Store COUNT contiguous registers to thread STATE starting from REGNUM */
  94 #define STORE_REGS(state, regnum, count) \
  95   memcpy (REG_ADDRESS (state, regnum), \
  96           &registers[REGISTER_BYTE (regnum)], \
  97           count*REGISTER_SIZE)
  98 \f
  99 /*
 100  * Fetch inferiors registers for gdb.
 101  * REGNO specifies which (as gdb views it) register, -1 for all.
 102  */
 103
 104 void
 105 fetch_inferior_registers (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 (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 \f
 209
 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 (int regno, CORE_ADDR blockend)
 224 {
 225   CORE_ADDR addr;
 226
 227   if (regno < 0 || regno >= NUM_REGS)
 228     error ("Invalid register number %d.", regno);
 229
 230   /* UAREA_SIZE == 8 kB in i386 */
 231   addr = (unsigned int) REG_ADDRESS (UAREA_SIZE - sizeof (struct i386_thread_state), regno);
 232
 233   return addr;
 234 }
 235
 236 /* jtv@hut.fi: I copied and modified this 387 code from
 237  * gdb/i386-xdep.c. Modifications for Mach 3.0.
 238  *
 239  * i387 status dumper. See also i387-tdep.c
 240  */
 241 struct env387
 242 {
 243   unsigned short control;
 244   unsigned short r0;
 245   unsigned short status;
 246   unsigned short r1;
 247   unsigned short tag;
 248   unsigned short r2;
 249   unsigned long eip;
 250   unsigned short code_seg;
 251   unsigned short opcode;
 252   unsigned long operand;
 253   unsigned short operand_seg;
 254   unsigned short r3;
 255   unsigned char regs[8][10];
 256 };
 257 /* This routine is machine independent?
 258  * Should move it to i387-tdep.c but you need to export struct env387
 259  */
 260 private
 261 print_387_status (unsigned short status, struct env387 *ep)
 262 {
 263   int i;
 264   int bothstatus;
 265   int top;
 266   int fpreg;
 267   unsigned char *p;
 268
 269   bothstatus = ((status != 0) && (ep->status != 0));
 270   if (status != 0)
 271     {
 272       if (bothstatus)
 273         printf_unfiltered ("u: ");
 274       print_387_status_word (status);
 275     }
 276
 277   if (ep->status != 0)
 278     {
 279       if (bothstatus)
 280         printf_unfiltered ("e: ");
 281       print_387_status_word (ep->status);
 282     }
 283
 284   print_387_control_word (ep->control);
 285   printf_unfiltered ("last exception: ");
 286   printf_unfiltered ("opcode %s; ", local_hex_string (ep->opcode));
 287   printf_unfiltered ("pc %s:", local_hex_string (ep->code_seg));
 288   printf_unfiltered ("%s; ", local_hex_string (ep->eip));
 289   printf_unfiltered ("operand %s", local_hex_string (ep->operand_seg));
 290   printf_unfiltered (":%s\n", local_hex_string (ep->operand));
 291
 292   top = (ep->status >> 11) & 7;
 293
 294   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 295   for (fpreg = 7; fpreg >= 0; fpreg--)
 296     {
 297       double val;
 298
 299       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 300
 301       switch ((ep->tag >> (fpreg * 2)) & 3)
 302         {
 303         case 0:
 304           printf_unfiltered ("valid ");
 305           break;
 306         case 1:
 307           printf_unfiltered ("zero  ");
 308           break;
 309         case 2:
 310           printf_unfiltered ("trap  ");
 311           break;
 312         case 3:
 313           printf_unfiltered ("empty ");
 314           break;
 315         }
 316       for (i = 9; i >= 0; i--)
 317         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 318
 319       floatformat_to_double (&floatformat_i387_ext, (char *) ep->regs[fpreg],
 320                              &val);
 321       printf_unfiltered ("  %g\n", val);
 322     }
 323   if (ep->r0)
 324     printf_unfiltered ("warning: reserved0 is %s\n", local_hex_string (ep->r0));
 325   if (ep->r1)
 326     printf_unfiltered ("warning: reserved1 is %s\n", local_hex_string (ep->r1));
 327   if (ep->r2)
 328     printf_unfiltered ("warning: reserved2 is %s\n", local_hex_string (ep->r2));
 329   if (ep->r3)
 330     printf_unfiltered ("warning: reserved3 is %s\n", local_hex_string (ep->r3));
 331 }
 332
 333 /*
 334  * values that go into fp_kind (from <i386/fpreg.h>)
 335  */
 336 #define FP_NO   0               /* no fp chip, no emulator (no fp support)      */
 337 #define FP_SW   1               /* no fp chip, using software emulator          */
 338 #define FP_HW   2               /* chip present bit                             */
 339 #define FP_287  2               /* 80287 chip present                           */
 340 #define FP_387  3               /* 80387 chip present                           */
 341
 342 typedef struct fpstate
 343 {
 344 #if 1
 345   unsigned char state[FP_STATE_BYTES];  /* "hardware" state */
 346 #else
 347   struct env387 state;          /* Actually this */
 348 #endif
 349   int status;                   /* Duplicate status */
 350 }
 351  *fpstate_t;
 352
 353 /* Mach 3 specific routines.
 354  */
 355 private boolean_t
 356 get_i387_state (struct fpstate *fstate)
 357 {
 358   kern_return_t ret;
 359   thread_state_data_t state;
 360   unsigned int fsCnt = i386_FLOAT_STATE_COUNT;
 361   struct i386_float_state *fsp;
 362
 363   ret = thread_get_state (current_thread,
 364                           i386_FLOAT_STATE,
 365                           state,
 366                           &fsCnt);
 367
 368   if (ret != KERN_SUCCESS)
 369     {
 370       warning ("Can not get live floating point state: %s",
 371                mach_error_string (ret));
 372       return FALSE;
 373     }
 374
 375   fsp = (struct i386_float_state *) state;
 376   /* The 387 chip (also 486 counts) or a software emulator? */
 377   if (!fsp->initialized || (fsp->fpkind != FP_387 && fsp->fpkind != FP_SW))
 378     return FALSE;
 379
 380   /* Clear the target then copy thread's float state there.
 381      Make a copy of the status word, for some reason?
 382    */
 383   memset (fstate, 0, sizeof (struct fpstate));
 384
 385   fstate->status = fsp->exc_status;
 386
 387   memcpy (fstate->state, (char *) &fsp->hw_state, FP_STATE_BYTES);
 388
 389   return TRUE;
 390 }
 391
 392 private boolean_t
 393 get_i387_core_state (struct fpstate *fstate)
 394 {
 395   /* Not implemented yet. Core files do not contain float state. */
 396   return FALSE;
 397 }
 398
 399 /*
 400  * This is called by "info float" command
 401  */
 402 void
 403 i386_mach3_float_info (void)
 404 {
 405   char buf[sizeof (struct fpstate) + 2 * sizeof (int)];
 406   boolean_t valid = FALSE;
 407   fpstate_t fps;
 408
 409   if (target_has_execution)
 410     valid = get_i387_state (buf);
 411 #if 0
 412   else if (WE HAVE CORE FILE)   /* @@@@ Core files not supported */
 413     valid = get_i387_core_state (buf);
 414 #endif
 415
 416   if (!valid)
 417     {
 418       warning ("no floating point status saved");
 419       return;
 420     }
 421
 422   fps = (fpstate_t) buf;
 423
 424   print_387_status (fps->status, (struct env387 *) fps->state);
 425 }