gdb/i386aix-nat.c

   1 /* Intel 386 native support.
   2    Copyright 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,
   3    2000, 2001 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "frame.h"
  24 #include "inferior.h"
  25 #include "language.h"
  26 #include "gdbcore.h"
  27 #include "regcache.h"
  28
  29 #ifdef USG
  30 #include <sys/types.h>
  31 #endif
  32
  33 #include <sys/param.h>
  34 #include <sys/dir.h>
  35 #include <signal.h>
  36 #include <sys/user.h>
  37 #include <sys/ioctl.h>
  38 #include <fcntl.h>
  39
  40 #include <sys/file.h>
  41 #include "gdb_stat.h"
  42
  43 #include <stddef.h>
  44 #include <sys/ptrace.h>
  45
  46 /* Does AIX define this in <errno.h>?  */
  47 extern int errno;
  48
  49 #ifdef HAVE_SYS_REG_H
  50 #include <sys/reg.h>
  51 #endif
  52
  53 #include "floatformat.h"
  54
  55 #include "target.h"
  56
  57 static void fetch_core_registers (char *, unsigned, int, CORE_ADDR);
  58 \f
  59
  60 /* this table must line up with REGISTER_NAMES in tm-i386v.h */
  61 /* symbols like 'EAX' come from <sys/reg.h> */
  62 static int regmap[] =
  63 {
  64   EAX, ECX, EDX, EBX,
  65   USP, EBP, ESI, EDI,
  66   EIP, EFL, CS, SS,
  67   DS, ES, FS, GS,
  68 };
  69
  70 /* blockend is the value of u.u_ar0, and points to the
  71  * place where GS is stored
  72  */
  73
  74 int
  75 i386_register_u_addr (int blockend, int regnum)
  76 {
  77 #if 0
  78   /* this will be needed if fp registers are reinstated */
  79   /* for now, you can look at them with 'info float'
  80    * sys5 wont let you change them with ptrace anyway
  81    */
  82   if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM)
  83     {
  84       int ubase, fpstate;
  85       struct user u;
  86       ubase = blockend + 4 * (SS + 1) - KSTKSZ;
  87       fpstate = ubase + ((char *) &u.u_fpstate - (char *) &u);
  88       return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM));
  89     }
  90   else
  91 #endif
  92     return (blockend + 4 * regmap[regnum]);
  93
  94 }
  95
  96 /* The code below only work on the aix ps/2 (i386-ibm-aix) -
  97  * mtranle@paris - Sat Apr 11 10:34:12 1992
  98  */
  99
 100 struct env387
 101 {
 102   unsigned short control;
 103   unsigned short r0;
 104   unsigned short status;
 105   unsigned short r1;
 106   unsigned short tag;
 107   unsigned short r2;
 108   unsigned long eip;
 109   unsigned short code_seg;
 110   unsigned short opcode;
 111   unsigned long operand;
 112   unsigned short operand_seg;
 113   unsigned short r3;
 114   unsigned char regs[8][10];
 115 };
 116
 117 static
 118 print_387_status (unsigned short status, struct env387 *ep)
 119 {
 120   int i;
 121   int bothstatus;
 122   int top;
 123   int fpreg;
 124   unsigned char *p;
 125
 126   bothstatus = ((status != 0) && (ep->status != 0));
 127   if (status != 0)
 128     {
 129       if (bothstatus)
 130         printf_unfiltered ("u: ");
 131       print_387_status_word (status);
 132     }
 133
 134   if (ep->status != 0)
 135     {
 136       if (bothstatus)
 137         printf_unfiltered ("e: ");
 138       print_387_status_word (ep->status);
 139     }
 140
 141   print_387_control_word (ep->control);
 142   printf_unfiltered ("last exception: ");
 143   printf_unfiltered ("opcode %s; ", local_hex_string (ep->opcode));
 144   printf_unfiltered ("pc %s:", local_hex_string (ep->code_seg));
 145   printf_unfiltered ("%s; ", local_hex_string (ep->eip));
 146   printf_unfiltered ("operand %s", local_hex_string (ep->operand_seg));
 147   printf_unfiltered (":%s\n", local_hex_string (ep->operand));
 148
 149   top = ((ep->status >> 11) & 7);
 150
 151   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 152   for (fpreg = 7; fpreg >= 0; fpreg--)
 153     {
 154       double val;
 155
 156       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 157
 158       switch ((ep->tag >> ((7 - fpreg) * 2)) & 3)
 159         {
 160         case 0:
 161           printf_unfiltered ("valid ");
 162           break;
 163         case 1:
 164           printf_unfiltered ("zero  ");
 165           break;
 166         case 2:
 167           printf_unfiltered ("trap  ");
 168           break;
 169         case 3:
 170           printf_unfiltered ("empty ");
 171           break;
 172         }
 173       for (i = 9; i >= 0; i--)
 174         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 175
 176       i387_to_double ((char *) ep->regs[fpreg], (char *) &val);
 177       printf_unfiltered ("  %#g\n", val);
 178     }
 179 }
 180
 181 static struct env387 core_env387;
 182
 183 void
 184 i386_float_info (void)
 185 {
 186   struct env387 fps;
 187   int fpsaved = 0;
 188   /* We need to reverse the order of the registers.  Apparently AIX stores
 189      the highest-numbered ones first.  */
 190   struct env387 fps_fixed;
 191   int i;
 192
 193   if (! ptid_equal (inferior_ptid, null_ptid))
 194     {
 195       char buf[10];
 196       unsigned short status;
 197
 198       ptrace (PT_READ_FPR, PIDGET (inferior_ptid), buf,
 199               offsetof (struct env387, status));
 200       memcpy (&status, buf, sizeof (status));
 201       fpsaved = status;
 202     }
 203   else
 204     {
 205       if ((fpsaved = core_env387.status) != 0)
 206         memcpy (&fps, &core_env387, sizeof (fps));
 207     }
 208
 209   if (fpsaved == 0)
 210     {
 211       printf_unfiltered ("no floating point status saved\n");
 212       return;
 213     }
 214
 215   if (! ptid_equal (inferior_ptid, null_ptid))
 216     {
 217       int offset;
 218       for (offset = 0; offset < sizeof (fps); offset += 10)
 219         {
 220           char buf[10];
 221           ptrace (PT_READ_FPR, PIDGET (inferior_ptid), buf, offset);
 222           memcpy ((char *) &fps.control + offset, buf,
 223                   MIN (10, sizeof (fps) - offset));
 224         }
 225     }
 226   fps_fixed = fps;
 227   for (i = 0; i < 8; ++i)
 228     memcpy (fps_fixed.regs[i], fps.regs[7 - i], 10);
 229   print_387_status (0, &fps_fixed);
 230 }
 231
 232 /* Fetch one register.  */
 233 static void
 234 fetch_register (int regno)
 235 {
 236   char buf[MAX_REGISTER_RAW_SIZE];
 237   if (regno < FP0_REGNUM)
 238     *(int *) buf = ptrace (PT_READ_GPR, PIDGET (inferior_ptid),
 239                            PT_REG (regmap[regno]), 0, 0);
 240   else
 241     ptrace (PT_READ_FPR, PIDGET (inferior_ptid), buf,
 242             (regno - FP0_REGNUM) * 10 + offsetof (struct env387, regs));
 243   supply_register (regno, buf);
 244 }
 245
 246 void
 247 fetch_inferior_registers (int regno)
 248 {
 249   if (regno < 0)
 250     for (regno = 0; regno < NUM_REGS; regno++)
 251       fetch_register (regno);
 252   else
 253     fetch_register (regno);
 254 }
 255
 256 /* store one register */
 257 static void
 258 store_register (int regno)
 259 {
 260   char buf[80];
 261   errno = 0;
 262   if (regno < FP0_REGNUM)
 263     ptrace (PT_WRITE_GPR, PIDGET (inferior_ptid), PT_REG (regmap[regno]),
 264             *(int *) &registers[REGISTER_BYTE (regno)], 0);
 265   else
 266     ptrace (PT_WRITE_FPR, PIDGET (inferior_ptid),
 267             &registers[REGISTER_BYTE (regno)],
 268             (regno - FP0_REGNUM) * 10 + offsetof (struct env387, regs));
 269
 270   if (errno != 0)
 271     {
 272       sprintf (buf, "writing register number %d", regno);
 273       perror_with_name (buf);
 274     }
 275 }
 276
 277 /* Store our register values back into the inferior.
 278    If REGNO is -1, do this for all registers.
 279    Otherwise, REGNO specifies which register (so we can save time).  */
 280 void
 281 store_inferior_registers (int regno)
 282 {
 283   if (regno < 0)
 284     for (regno = 0; regno < NUM_REGS; regno++)
 285       store_register (regno);
 286   else
 287     store_register (regno);
 288 }
 289
 290 #ifndef CD_AX                   /* defined in sys/i386/coredump.h */
 291 #define CD_AX   0
 292 #define CD_BX   1
 293 #define CD_CX   2
 294 #define CD_DX   3
 295 #define CD_SI   4
 296 #define CD_DI   5
 297 #define CD_BP   6
 298 #define CD_SP   7
 299 #define CD_FL   8
 300 #define CD_IP   9
 301 #define CD_CS   10
 302 #define CD_DS   11
 303 #define CD_ES   12
 304 #define CD_FS   13
 305 #define CD_GS   14
 306 #define CD_SS   15
 307 #endif
 308
 309 /*
 310  * The order here in core_regmap[] has to be the same as in
 311  * regmap[] above.
 312  */
 313 static int core_regmap[] =
 314 {
 315   CD_AX, CD_CX, CD_DX, CD_BX,
 316   CD_SP, CD_BP, CD_SI, CD_DI,
 317   CD_IP, CD_FL, CD_CS, CD_SS,
 318   CD_DS, CD_ES, CD_FS, CD_GS,
 319 };
 320
 321 /* Provide registers to GDB from a core file.
 322
 323    CORE_REG_SECT points to an array of bytes, which were obtained from
 324    a core file which BFD thinks might contain register contents.
 325    CORE_REG_SIZE is its size.
 326
 327    WHICH says which register set corelow suspects this is:
 328      0 --- the general-purpose register set
 329      2 --- the floating-point register set
 330
 331    REG_ADDR isn't used.  */
 332
 333 static void
 334 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 335                       int which, CORE_ADDR reg_addr)
 336 {
 337
 338   if (which == 0)
 339     {
 340       /* Integer registers */
 341
 342 #define cd_regs(n) ((int *)core_reg_sect)[n]
 343 #define regs(n) *((int *) &registers[REGISTER_BYTE (n)])
 344
 345       int i;
 346       for (i = 0; i < FP0_REGNUM; i++)
 347         regs (i) = cd_regs (core_regmap[i]);
 348     }
 349   else if (which == 2)
 350     {
 351       /* Floating point registers */
 352
 353       if (core_reg_size >= sizeof (core_env387))
 354         memcpy (&core_env387, core_reg_sect, core_reg_size);
 355       else
 356         fprintf_unfiltered (gdb_stderr, "Couldn't read float regs from core file\n");
 357     }
 358 }
 359 \f
 360
 361 /* Register that we are able to handle i386aix core file formats.
 362    FIXME: is this really bfd_target_unknown_flavour? */
 363
 364 static struct core_fns i386aix_core_fns =
 365 {
 366   bfd_target_unknown_flavour,           /* core_flavour */
 367   default_check_format,                 /* check_format */
 368   default_core_sniffer,                 /* core_sniffer */
 369   fetch_core_registers,                 /* core_read_registers */
 370   NULL                                  /* next */
 371 };
 372
 373 void
 374 _initialize_core_i386aix (void)
 375 {
 376   add_core_fns (&i386aix_core_fns);
 377 }