gdb/i386gnu-nat.c

   1 /* Low level interface to I386 running the GNU Hurd
   2    Copyright (C) 1992, 1995, 1996 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 #include <errno.h>
  26
  27 #include <mach.h>
  28 #include <mach/message.h>
  29 #include <mach/exception.h>
  30 #include <mach_error.h>
  31
  32 #include "gnu-nat.h"
  33
  34 /* Hmmm... Should this not be here?
  35  * Now for i386_float_info() target_has_execution
  36  */
  37 #include <target.h>
  38
  39 /* @@@ Should move print_387_status() to i387-tdep.c */
  40 extern void print_387_control_word ();          /* i387-tdep.h */
  41 extern void print_387_status_word ();
  42 \f
  43 /* Find offsets to thread states at compile time.
  44  * If your compiler does not grok this, calculate offsets
  45  * offsets yourself and use them (or get a compatible compiler :-)
  46  */
  47
  48 #define  REG_OFFSET(reg) (int)(&((struct i386_thread_state *)0)->reg)
  49
  50 /* at reg_offset[i] is the offset to the i386_thread_state
  51  * location where the gdb registers[i] is stored.
  52  */
  53
  54 static int reg_offset[] =
  55 {
  56   REG_OFFSET(eax),  REG_OFFSET(ecx), REG_OFFSET(edx), REG_OFFSET(ebx),
  57   REG_OFFSET(uesp), REG_OFFSET(ebp), REG_OFFSET(esi), REG_OFFSET(edi),
  58   REG_OFFSET(eip),  REG_OFFSET(efl), REG_OFFSET(cs),  REG_OFFSET(ss),
  59   REG_OFFSET(ds),   REG_OFFSET(es),  REG_OFFSET(fs),  REG_OFFSET(gs)
  60 };
  61
  62 #define REG_ADDR(state,regnum) ((char *)(state)+reg_offset[regnum])
  63
  64 /* Fetch COUNT contiguous registers from thread STATE starting from REGNUM
  65  * Caller knows that the regs handled in one transaction are of same size.
  66  */
  67 #define FETCH_REGS(state, regnum, count) \
  68   memcpy (&registers[REGISTER_BYTE (regnum)], \
  69           REG_ADDR (state, regnum), \
  70           count * REGISTER_RAW_SIZE (regnum))
  71
  72 /* Store COUNT contiguous registers to thread STATE starting from REGNUM */
  73 #define STORE_REGS(state, regnum, count) \
  74   memcpy (REG_ADDR (state, regnum), \
  75           &registers[REGISTER_BYTE (regnum)], \
  76           count * REGISTER_RAW_SIZE (regnum))
  77 \f
  78 /*
  79  * Fetch inferiors registers for gdb.
  80  * REG specifies which (as gdb views it) register, -1 for all.
  81  */
  82 void
  83 gnu_fetch_registers (int reg)
  84 {
  85   struct proc *thread;
  86   thread_state_t state;
  87
  88   inf_update_procs (current_inferior); /* Make sure we know about new threads.  */
  89
  90   thread = inf_tid_to_thread (current_inferior, inferior_pid);
  91   if (! thread)
  92     error ("fetch inferior registers: %d: Invalid thread", inferior_pid);
  93
  94   state = proc_get_state (thread, 0);
  95
  96   if (! state)
  97     warning ("Couldn't fetch register %s from %s (invalid thread).",
  98              REGISTER_NAME (reg), proc_string (thread));
  99   else if (reg >= 0)
 100     {
 101       proc_debug (thread, "fetching register: %s", REGISTER_NAME (reg));
 102       supply_register (reg, REG_ADDR(state, reg));
 103       thread->fetched_regs |= (1 << reg);
 104     }
 105   else
 106     {
 107       proc_debug (thread, "fetching all registers");
 108       for (reg = 0; reg < NUM_REGS; reg++)
 109         supply_register (reg, REG_ADDR(state, reg));
 110       thread->fetched_regs = ~0;
 111     }
 112 }
 113 \f
 114 /* Store our register values back into the inferior.
 115  * If REG is -1, do this for all registers.
 116  * Otherwise, REG specifies which register
 117  *
 118  * On mach3 all registers are always saved in one call.
 119  */
 120 void
 121 gnu_store_registers (reg)
 122      int reg;
 123 {
 124   struct proc *thread;
 125   int was_aborted, was_valid;
 126   thread_state_t state;
 127   thread_state_data_t old_state;
 128
 129   inf_update_procs (current_inferior); /* Make sure we know about new threads.  */
 130
 131   thread = inf_tid_to_thread (current_inferior, inferior_pid);
 132   if (! thread)
 133     error ("store inferior registers: %d: Invalid thread", inferior_pid);
 134
 135   proc_debug (thread, "storing register %s.", REGISTER_NAME (reg));
 136
 137   was_aborted = thread->aborted;
 138   was_valid = thread->state_valid;
 139   if (! was_aborted && was_valid)
 140     bcopy (&thread->state, &old_state, sizeof (old_state));
 141
 142   state = proc_get_state (thread, 1);
 143
 144   if (! state)
 145     warning ("Couldn't store register %s from %s (invalid thread).",
 146              REGISTER_NAME (reg), proc_string (thread));
 147   else
 148     {
 149       if (! was_aborted && was_valid)
 150         /* See which registers have changed after aborting the thread.  */
 151         {
 152           int check_reg;
 153           for (check_reg = 0; check_reg < NUM_REGS; check_reg++)
 154             if ((thread->fetched_regs & (1 << check_reg))
 155                 && bcmp (REG_ADDR (&old_state, check_reg),
 156                          REG_ADDR (state, check_reg),
 157                          REGISTER_RAW_SIZE (check_reg)))
 158               /* Register CHECK_REG has changed!  Ack!  */
 159               {
 160                 warning ("Register %s changed after thread was aborted.",
 161                          REGISTER_NAME (check_reg));
 162                 if (reg >= 0 && reg != check_reg)
 163                   /* Update gdb's copy of the register.  */
 164                   supply_register (check_reg, REG_ADDR (state, check_reg));
 165                 else
 166                   warning ("... also writing this register!  Suspicious...");
 167               }
 168         }
 169
 170       if (reg >= 0)
 171         {
 172           proc_debug (thread, "storing register: %s", REGISTER_NAME (reg));
 173           STORE_REGS (state, reg, 1);
 174         }
 175       else
 176         {
 177           proc_debug (thread, "storing all registers");
 178           for (reg = 0; reg < NUM_REGS; reg++)
 179             STORE_REGS (state, reg, 1);
 180         }
 181     }
 182 }
 183 \f
 184 /* jtv@hut.fi: I copied and modified this 387 code from
 185  * gdb/i386-xdep.c. Modifications for Mach 3.0.
 186  *
 187  * i387 status dumper. See also i387-tdep.c
 188  */
 189 struct env387
 190 {
 191   unsigned short control;
 192   unsigned short r0;
 193   unsigned short status;
 194   unsigned short r1;
 195   unsigned short tag;
 196   unsigned short r2;
 197   unsigned long eip;
 198   unsigned short code_seg;
 199   unsigned short opcode;
 200   unsigned long operand;
 201   unsigned short operand_seg;
 202   unsigned short r3;
 203   unsigned char regs[8][10];
 204 };
 205 /* This routine is machine independent?
 206  * Should move it to i387-tdep.c but you need to export struct env387
 207  */
 208 static
 209 print_387_status (status, ep)
 210      unsigned short status;
 211      struct env387 *ep;
 212 {
 213   int i;
 214   int bothstatus;
 215   int top;
 216   int fpreg;
 217   unsigned char *p;
 218
 219   bothstatus = ((status != 0) && (ep->status != 0));
 220   if (status != 0)
 221     {
 222       if (bothstatus)
 223         printf_unfiltered ("u: ");
 224       print_387_status_word (status);
 225     }
 226
 227   if (ep->status != 0)
 228     {
 229       if (bothstatus)
 230         printf_unfiltered ("e: ");
 231       print_387_status_word (ep->status);
 232     }
 233
 234   print_387_control_word (ep->control);
 235   printf_unfiltered ("last exception: ");
 236   printf_unfiltered ("opcode %s; ", local_hex_string(ep->opcode));
 237   printf_unfiltered ("pc %s:", local_hex_string(ep->code_seg));
 238   printf_unfiltered ("%s; ", local_hex_string(ep->eip));
 239   printf_unfiltered ("operand %s", local_hex_string(ep->operand_seg));
 240   printf_unfiltered (":%s\n", local_hex_string(ep->operand));
 241
 242   top = (ep->status >> 11) & 7;
 243
 244   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 245   for (fpreg = 7; fpreg >= 0; fpreg--)
 246     {
 247       double val;
 248
 249       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 250
 251       switch ((ep->tag >> (fpreg * 2)) & 3)
 252         {
 253         case 0: printf_unfiltered ("valid "); break;
 254         case 1: printf_unfiltered ("zero  "); break;
 255         case 2: printf_unfiltered ("trap  "); break;
 256         case 3: printf_unfiltered ("empty "); break;
 257         }
 258       for (i = 9; i >= 0; i--)
 259         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 260
 261       floatformat_to_double (&floatformat_i387_ext, (char *)ep->regs[fpreg],
 262                                &val);
 263       printf_unfiltered ("  %g\n", val);
 264     }
 265   if (ep->r0)
 266     printf_unfiltered ("warning: reserved0 is %s\n", local_hex_string(ep->r0));
 267   if (ep->r1)
 268     printf_unfiltered ("warning: reserved1 is %s\n", local_hex_string(ep->r1));
 269   if (ep->r2)
 270     printf_unfiltered ("warning: reserved2 is %s\n", local_hex_string(ep->r2));
 271   if (ep->r3)
 272     printf_unfiltered ("warning: reserved3 is %s\n", local_hex_string(ep->r3));
 273 }
 274
 275 /*
 276  * values that go into fp_kind (from <i386/fpreg.h>)
 277  */
 278 #define FP_NO   0       /* no fp chip, no emulator (no fp support)      */
 279 #define FP_SW   1       /* no fp chip, using software emulator          */
 280 #define FP_HW   2       /* chip present bit                             */
 281 #define FP_287  2       /* 80287 chip present                           */
 282 #define FP_387  3       /* 80387 chip present                           */
 283
 284 typedef struct fpstate {
 285 #if 1
 286   unsigned char state[FP_STATE_BYTES]; /* "hardware" state */
 287 #else
 288   struct env387 state;  /* Actually this */
 289 #endif
 290   int status;           /* Duplicate status */
 291 } *fpstate_t;
 292
 293 /* Mach 3 specific routines.
 294  */
 295 static int
 296 get_i387_state (fstate)
 297      struct fpstate *fstate;
 298 {
 299   error_t err;
 300   thread_state_data_t state;
 301   unsigned int fsCnt = i386_FLOAT_STATE_COUNT;
 302   struct i386_float_state *fsp;
 303   struct proc *thread = inf_tid_to_thread (current_inferior, inferior_pid);
 304
 305   if (!thread)
 306     error ("get_i387_state: Invalid thread");
 307
 308   proc_abort (thread, 0);       /* Make sure THREAD's in a reasonable state. */
 309
 310   err = thread_get_state (thread->port, i386_FLOAT_STATE, state, &fsCnt);
 311   if (err)
 312     {
 313       warning ("Can not get live floating point state: %s",
 314                mach_error_string (err));
 315       return 0;
 316     }
 317
 318   fsp = (struct i386_float_state *)state;
 319   /* The 387 chip (also 486 counts) or a software emulator? */
 320   if (!fsp->initialized || (fsp->fpkind != FP_387 && fsp->fpkind != FP_SW))
 321     return 0;
 322
 323   /* Clear the target then copy thread's float state there.
 324      Make a copy of the status word, for some reason?
 325    */
 326   memset (fstate, 0, sizeof (struct fpstate));
 327
 328   fstate->status = fsp->exc_status;
 329
 330   memcpy (fstate->state, (char *)&fsp->hw_state, FP_STATE_BYTES);
 331
 332   return 1;
 333 }
 334
 335 /*
 336  * This is called by "info float" command
 337  */
 338 void
 339 i386_mach3_float_info()
 340 {
 341   char buf [sizeof (struct fpstate) + 2 * sizeof (int)];
 342   int valid = 0;
 343   fpstate_t fps;
 344
 345   if (target_has_execution)
 346     valid = get_i387_state (buf);
 347
 348   if (!valid)
 349     {
 350       warning ("no floating point status saved");
 351       return;
 352     }
 353
 354   fps = (fpstate_t) buf;
 355
 356   print_387_status (fps->status, (struct env387 *)fps->state);
 357 }