gdb/arch-utils.c

   1 /* Dynamic architecture support for GDB, the GNU debugger.
   2    Copyright 1998, 1999, 2000, 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
  23 #if GDB_MULTI_ARCH
  24 #include "gdbcmd.h"
  25 #include "inferior.h"           /* enum CALL_DUMMY_LOCATION et.al. */
  26 #else
  27 /* Just include everything in sight so that the every old definition
  28    of macro is visible. */
  29 #include "gdb_string.h"
  30 #include "symtab.h"
  31 #include "frame.h"
  32 #include "inferior.h"
  33 #include "breakpoint.h"
  34 #include "gdb_wait.h"
  35 #include "gdbcore.h"
  36 #include "gdbcmd.h"
  37 #include "target.h"
  38 #include "annotate.h"
  39 #endif
  40 #include "regcache.h"
  41
  42 #include "version.h"
  43
  44 #include "floatformat.h"
  45
  46 /* Use the program counter to determine the contents and size
  47    of a breakpoint instruction.  If no target-dependent macro
  48    BREAKPOINT_FROM_PC has been defined to implement this function,
  49    assume that the breakpoint doesn't depend on the PC, and
  50    use the values of the BIG_BREAKPOINT and LITTLE_BREAKPOINT macros.
  51    Return a pointer to a string of bytes that encode a breakpoint
  52    instruction, stores the length of the string to *lenptr,
  53    and optionally adjust the pc to point to the correct memory location
  54    for inserting the breakpoint.  */
  55
  56 unsigned char *
  57 legacy_breakpoint_from_pc (CORE_ADDR * pcptr, int *lenptr)
  58 {
  59   /* {BIG_,LITTLE_}BREAKPOINT is the sequence of bytes we insert for a
  60      breakpoint.  On some machines, breakpoints are handled by the
  61      target environment and we don't have to worry about them here.  */
  62 #ifdef BIG_BREAKPOINT
  63   if (TARGET_BYTE_ORDER == BIG_ENDIAN)
  64     {
  65       static unsigned char big_break_insn[] = BIG_BREAKPOINT;
  66       *lenptr = sizeof (big_break_insn);
  67       return big_break_insn;
  68     }
  69 #endif
  70 #ifdef LITTLE_BREAKPOINT
  71   if (TARGET_BYTE_ORDER != BIG_ENDIAN)
  72     {
  73       static unsigned char little_break_insn[] = LITTLE_BREAKPOINT;
  74       *lenptr = sizeof (little_break_insn);
  75       return little_break_insn;
  76     }
  77 #endif
  78 #ifdef BREAKPOINT
  79   {
  80     static unsigned char break_insn[] = BREAKPOINT;
  81     *lenptr = sizeof (break_insn);
  82     return break_insn;
  83   }
  84 #endif
  85   *lenptr = 0;
  86   return NULL;
  87 }
  88
  89 int
  90 generic_frameless_function_invocation_not (struct frame_info *fi)
  91 {
  92   return 0;
  93 }
  94
  95 int
  96 generic_return_value_on_stack_not (struct type *type)
  97 {
  98   return 0;
  99 }
 100
 101 char *
 102 legacy_register_name (int i)
 103 {
 104 #ifdef REGISTER_NAMES
 105   static char *names[] = REGISTER_NAMES;
 106   if (i < 0 || i >= (sizeof (names) / sizeof (*names)))
 107     return NULL;
 108   else
 109     return names[i];
 110 #else
 111   internal_error (__FILE__, __LINE__,
 112                   "legacy_register_name: called.");
 113   return NULL;
 114 #endif
 115 }
 116
 117 #if defined (CALL_DUMMY)
 118 LONGEST legacy_call_dummy_words[] = CALL_DUMMY;
 119 #else
 120 LONGEST legacy_call_dummy_words[1];
 121 #endif
 122 int legacy_sizeof_call_dummy_words = sizeof (legacy_call_dummy_words);
 123
 124 void
 125 generic_remote_translate_xfer_address (CORE_ADDR gdb_addr, int gdb_len,
 126                                        CORE_ADDR * rem_addr, int *rem_len)
 127 {
 128   *rem_addr = gdb_addr;
 129   *rem_len = gdb_len;
 130 }
 131
 132 int
 133 generic_prologue_frameless_p (CORE_ADDR ip)
 134 {
 135 #ifdef SKIP_PROLOGUE_FRAMELESS_P
 136   return ip == SKIP_PROLOGUE_FRAMELESS_P (ip);
 137 #else
 138   return ip == SKIP_PROLOGUE (ip);
 139 #endif
 140 }
 141
 142
 143 /* Helper functions for INNER_THAN */
 144
 145 int
 146 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
 147 {
 148   return (lhs < rhs);
 149 }
 150
 151 int
 152 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
 153 {
 154   return (lhs > rhs);
 155 }
 156
 157
 158 /* Helper functions for TARGET_{FLOAT,DOUBLE}_FORMAT */
 159
 160 const struct floatformat *
 161 default_float_format (struct gdbarch *gdbarch)
 162 {
 163 #if GDB_MULTI_ARCH
 164   int byte_order = gdbarch_byte_order (gdbarch);
 165 #else
 166   int byte_order = TARGET_BYTE_ORDER;
 167 #endif
 168   switch (byte_order)
 169     {
 170     case BIG_ENDIAN:
 171       return &floatformat_ieee_single_big;
 172     case LITTLE_ENDIAN:
 173       return &floatformat_ieee_single_little;
 174     default:
 175       internal_error (__FILE__, __LINE__,
 176                       "default_float_format: bad byte order");
 177     }
 178 }
 179
 180
 181 const struct floatformat *
 182 default_double_format (struct gdbarch *gdbarch)
 183 {
 184 #if GDB_MULTI_ARCH
 185   int byte_order = gdbarch_byte_order (gdbarch);
 186 #else
 187   int byte_order = TARGET_BYTE_ORDER;
 188 #endif
 189   switch (byte_order)
 190     {
 191     case BIG_ENDIAN:
 192       return &floatformat_ieee_double_big;
 193     case LITTLE_ENDIAN:
 194       return &floatformat_ieee_double_little;
 195     default:
 196       internal_error (__FILE__, __LINE__,
 197                       "default_double_format: bad byte order");
 198     }
 199 }
 200
 201 /* Misc helper functions for targets. */
 202
 203 int
 204 frame_num_args_unknown (struct frame_info *fi)
 205 {
 206   return -1;
 207 }
 208
 209
 210 int
 211 generic_register_convertible_not (int num)
 212 {
 213   return 0;
 214 }
 215
 216
 217 int
 218 default_register_sim_regno (int num)
 219 {
 220   return num;
 221 }
 222
 223
 224 CORE_ADDR
 225 default_convert_from_func_ptr_addr (CORE_ADDR addr)
 226 {
 227   return addr;
 228 }
 229
 230 int
 231 no_op_reg_to_regnum (int reg)
 232 {
 233   return reg;
 234 }
 235
 236 /* For use by frame_args_address and frame_locals_address.  */
 237 CORE_ADDR
 238 default_frame_address (struct frame_info *fi)
 239 {
 240   return fi->frame;
 241 }
 242
 243 /* Default prepare_to_procced().  */
 244 int
 245 default_prepare_to_proceed (int select_it)
 246 {
 247   return 0;
 248 }
 249
 250 /* Generic prepare_to_proceed().  This one should be suitable for most
 251    targets that support threads. */
 252 int
 253 generic_prepare_to_proceed (int select_it)
 254 {
 255   ptid_t wait_ptid;
 256   struct target_waitstatus wait_status;
 257
 258   /* Get the last target status returned by target_wait().  */
 259   get_last_target_status (&wait_ptid, &wait_status);
 260
 261   /* Make sure we were stopped at a breakpoint.  */
 262   if (wait_status.kind != TARGET_WAITKIND_STOPPED
 263       || wait_status.value.sig != TARGET_SIGNAL_TRAP)
 264     {
 265       return 0;
 266     }
 267
 268   if (!ptid_equal (wait_ptid, minus_one_ptid)
 269       && !ptid_equal (inferior_ptid, wait_ptid))
 270     {
 271       /* Switched over from WAIT_PID.  */
 272       CORE_ADDR wait_pc = read_pc_pid (wait_ptid);
 273
 274       /* Avoid switching where it wouldn't do any good, i.e. if both
 275          threads are at the same breakpoint.  */
 276       if (wait_pc != read_pc () && breakpoint_here_p (wait_pc))
 277         {
 278           if (select_it)
 279             {
 280               /* User hasn't deleted the breakpoint.  Switch back to
 281                  WAIT_PID and return non-zero.  */
 282               inferior_ptid = wait_ptid;
 283
 284               /* FIXME: This stuff came from switch_to_thread() in
 285                  thread.c (which should probably be a public function).  */
 286               flush_cached_frames ();
 287               registers_changed ();
 288               stop_pc = wait_pc;
 289               select_frame (get_current_frame (), 0);
 290             }
 291
 292           return 1;
 293         }
 294     }
 295   return 0;
 296
 297 }
 298
 299 /* Functions to manipulate the endianness of the target.  */
 300
 301 #ifdef TARGET_BYTE_ORDER_SELECTABLE
 302 /* compat - Catch old targets that expect a selectable byte-order to
 303    default to BIG_ENDIAN */
 304 #ifndef TARGET_BYTE_ORDER_DEFAULT
 305 #define TARGET_BYTE_ORDER_DEFAULT BIG_ENDIAN
 306 #endif
 307 #endif
 308 #if !TARGET_BYTE_ORDER_SELECTABLE_P
 309 #ifndef TARGET_BYTE_ORDER_DEFAULT
 310 /* compat - Catch old non byte-order selectable targets that do not
 311    define TARGET_BYTE_ORDER_DEFAULT and instead expect
 312    TARGET_BYTE_ORDER to be used as the default.  For targets that
 313    defined neither TARGET_BYTE_ORDER nor TARGET_BYTE_ORDER_DEFAULT the
 314    below will get a strange compiler warning. */
 315 #define TARGET_BYTE_ORDER_DEFAULT TARGET_BYTE_ORDER
 316 #endif
 317 #endif
 318 #ifndef TARGET_BYTE_ORDER_DEFAULT
 319 #define TARGET_BYTE_ORDER_DEFAULT BIG_ENDIAN /* arbitrary */
 320 #endif
 321 /* ``target_byte_order'' is only used when non- multi-arch.
 322    Multi-arch targets obtain the current byte order using
 323    TARGET_BYTE_ORDER which is controlled by gdbarch.*. */
 324 int target_byte_order = TARGET_BYTE_ORDER_DEFAULT;
 325 int target_byte_order_auto = 1;
 326
 327 static const char endian_big[] = "big";
 328 static const char endian_little[] = "little";
 329 static const char endian_auto[] = "auto";
 330 static const char *endian_enum[] =
 331 {
 332   endian_big,
 333   endian_little,
 334   endian_auto,
 335   NULL,
 336 };
 337 static const char *set_endian_string;
 338
 339 /* Called by ``show endian''.  */
 340
 341 static void
 342 show_endian (char *args, int from_tty)
 343 {
 344   if (TARGET_BYTE_ORDER_AUTO)
 345     printf_unfiltered ("The target endianness is set automatically (currently %s endian)\n",
 346                        (TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little"));
 347   else
 348     printf_unfiltered ("The target is assumed to be %s endian\n",
 349                        (TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little"));
 350 }
 351
 352 static void
 353 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
 354 {
 355   if (!TARGET_BYTE_ORDER_SELECTABLE_P)
 356     {
 357       printf_unfiltered ("Byte order is not selectable.");
 358     }
 359   else if (set_endian_string == endian_auto)
 360     {
 361       target_byte_order_auto = 1;
 362     }
 363   else if (set_endian_string == endian_little)
 364     {
 365       target_byte_order_auto = 0;
 366       if (GDB_MULTI_ARCH)
 367         {
 368           struct gdbarch_info info;
 369           memset (&info, 0, sizeof info);
 370           info.byte_order = LITTLE_ENDIAN;
 371           if (! gdbarch_update_p (info))
 372             {
 373               printf_unfiltered ("Little endian target not supported by GDB\n");
 374             }
 375         }
 376       else
 377         {
 378           target_byte_order = LITTLE_ENDIAN;
 379         }
 380     }
 381   else if (set_endian_string == endian_big)
 382     {
 383       target_byte_order_auto = 0;
 384       if (GDB_MULTI_ARCH)
 385         {
 386           struct gdbarch_info info;
 387           memset (&info, 0, sizeof info);
 388           info.byte_order = BIG_ENDIAN;
 389           if (! gdbarch_update_p (info))
 390             {
 391               printf_unfiltered ("Big endian target not supported by GDB\n");
 392             }
 393         }
 394       else
 395         {
 396           target_byte_order = BIG_ENDIAN;
 397         }
 398     }
 399   else
 400     internal_error (__FILE__, __LINE__,
 401                     "set_endian: bad value");
 402   show_endian (NULL, from_tty);
 403 }
 404
 405 /* Set the endianness from a BFD.  */
 406
 407 static void
 408 set_endian_from_file (bfd *abfd)
 409 {
 410   if (GDB_MULTI_ARCH)
 411     internal_error (__FILE__, __LINE__,
 412                     "set_endian_from_file: not for multi-arch");
 413   if (TARGET_BYTE_ORDER_SELECTABLE_P)
 414     {
 415       int want;
 416
 417       if (bfd_big_endian (abfd))
 418         want = BIG_ENDIAN;
 419       else
 420         want = LITTLE_ENDIAN;
 421       if (TARGET_BYTE_ORDER_AUTO)
 422         target_byte_order = want;
 423       else if (TARGET_BYTE_ORDER != want)
 424         warning ("%s endian file does not match %s endian target.",
 425                  want == BIG_ENDIAN ? "big" : "little",
 426                  TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little");
 427     }
 428   else
 429     {
 430       if (bfd_big_endian (abfd)
 431           ? TARGET_BYTE_ORDER != BIG_ENDIAN
 432           : TARGET_BYTE_ORDER == BIG_ENDIAN)
 433         warning ("%s endian file does not match %s endian target.",
 434                  bfd_big_endian (abfd) ? "big" : "little",
 435                  TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little");
 436     }
 437 }
 438
 439
 440 /* Functions to manipulate the architecture of the target */
 441
 442 enum set_arch { set_arch_auto, set_arch_manual };
 443
 444 int target_architecture_auto = 1;
 445
 446 const char *set_architecture_string;
 447
 448 /* Old way of changing the current architecture. */
 449
 450 extern const struct bfd_arch_info bfd_default_arch_struct;
 451 const struct bfd_arch_info *target_architecture = &bfd_default_arch_struct;
 452 int (*target_architecture_hook) (const struct bfd_arch_info *ap);
 453
 454 static int
 455 arch_ok (const struct bfd_arch_info *arch)
 456 {
 457   if (GDB_MULTI_ARCH)
 458     internal_error (__FILE__, __LINE__,
 459                     "arch_ok: not multi-arched");
 460   /* Should be performing the more basic check that the binary is
 461      compatible with GDB. */
 462   /* Check with the target that the architecture is valid. */
 463   return (target_architecture_hook == NULL
 464           || target_architecture_hook (arch));
 465 }
 466
 467 static void
 468 set_arch (const struct bfd_arch_info *arch,
 469           enum set_arch type)
 470 {
 471   if (GDB_MULTI_ARCH)
 472     internal_error (__FILE__, __LINE__,
 473                     "set_arch: not multi-arched");
 474   switch (type)
 475     {
 476     case set_arch_auto:
 477       if (!arch_ok (arch))
 478         warning ("Target may not support %s architecture",
 479                  arch->printable_name);
 480       target_architecture = arch;
 481       break;
 482     case set_arch_manual:
 483       if (!arch_ok (arch))
 484         {
 485           printf_unfiltered ("Target does not support `%s' architecture.\n",
 486                              arch->printable_name);
 487         }
 488       else
 489         {
 490           target_architecture_auto = 0;
 491           target_architecture = arch;
 492         }
 493       break;
 494     }
 495   if (gdbarch_debug)
 496     gdbarch_dump (current_gdbarch, gdb_stdlog);
 497 }
 498
 499 /* Set the architecture from arch/machine (deprecated) */
 500
 501 void
 502 set_architecture_from_arch_mach (enum bfd_architecture arch,
 503                                  unsigned long mach)
 504 {
 505   const struct bfd_arch_info *wanted = bfd_lookup_arch (arch, mach);
 506   if (GDB_MULTI_ARCH)
 507     internal_error (__FILE__, __LINE__,
 508                     "set_architecture_from_arch_mach: not multi-arched");
 509   if (wanted != NULL)
 510     set_arch (wanted, set_arch_manual);
 511   else
 512     internal_error (__FILE__, __LINE__,
 513                     "gdbarch: hardwired architecture/machine not recognized");
 514 }
 515
 516 /* Set the architecture from a BFD (deprecated) */
 517
 518 static void
 519 set_architecture_from_file (bfd *abfd)
 520 {
 521   const struct bfd_arch_info *wanted = bfd_get_arch_info (abfd);
 522   if (GDB_MULTI_ARCH)
 523     internal_error (__FILE__, __LINE__,
 524                     "set_architecture_from_file: not multi-arched");
 525   if (target_architecture_auto)
 526     {
 527       set_arch (wanted, set_arch_auto);
 528     }
 529   else if (wanted != target_architecture)
 530     {
 531       warning ("%s architecture file may be incompatible with %s target.",
 532                wanted->printable_name,
 533                target_architecture->printable_name);
 534     }
 535 }
 536
 537
 538 /* Called if the user enters ``show architecture'' without an
 539    argument. */
 540
 541 static void
 542 show_architecture (char *args, int from_tty)
 543 {
 544   const char *arch;
 545   arch = TARGET_ARCHITECTURE->printable_name;
 546   if (target_architecture_auto)
 547     printf_filtered ("The target architecture is set automatically (currently %s)\n", arch);
 548   else
 549     printf_filtered ("The target architecture is assumed to be %s\n", arch);
 550 }
 551
 552
 553 /* Called if the user enters ``set architecture'' with or without an
 554    argument. */
 555
 556 static void
 557 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
 558 {
 559   if (strcmp (set_architecture_string, "auto") == 0)
 560     {
 561       target_architecture_auto = 1;
 562     }
 563   else if (GDB_MULTI_ARCH)
 564     {
 565       struct gdbarch_info info;
 566       memset (&info, 0, sizeof info);
 567       info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
 568       if (info.bfd_arch_info == NULL)
 569         internal_error (__FILE__, __LINE__,
 570                         "set_architecture: bfd_scan_arch failed");
 571       if (gdbarch_update_p (info))
 572         target_architecture_auto = 0;
 573       else
 574         printf_unfiltered ("Architecture `%s' not recognized.\n",
 575                            set_architecture_string);
 576     }
 577   else
 578     {
 579       const struct bfd_arch_info *arch
 580         = bfd_scan_arch (set_architecture_string);
 581       if (arch == NULL)
 582         internal_error (__FILE__, __LINE__,
 583                         "set_architecture: bfd_scan_arch failed");
 584       set_arch (arch, set_arch_manual);
 585     }
 586   show_architecture (NULL, from_tty);
 587 }
 588
 589 /* Called if the user enters ``info architecture'' without an argument. */
 590
 591 static void
 592 info_architecture (char *args, int from_tty)
 593 {
 594   printf_filtered ("Available architectures are:\n");
 595   if (GDB_MULTI_ARCH)
 596     {
 597       const char **arches = gdbarch_printable_names ();
 598       const char **arch;
 599       for (arch = arches; *arch != NULL; arch++)
 600         {
 601           printf_filtered (" %s", *arch);
 602         }
 603       xfree (arches);
 604     }
 605   else
 606     {
 607       enum bfd_architecture a;
 608       for (a = bfd_arch_obscure + 1; a < bfd_arch_last; a++)
 609         {
 610           const struct bfd_arch_info *ap;
 611           for (ap = bfd_lookup_arch (a, 0);
 612                ap != NULL;
 613                ap = ap->next)
 614             {
 615               printf_filtered (" %s", ap->printable_name);
 616               ap = ap->next;
 617             }
 618         }
 619     }
 620   printf_filtered ("\n");
 621 }
 622
 623 /* Set the dynamic target-system-dependent parameters (architecture,
 624    byte-order) using information found in the BFD */
 625
 626 void
 627 set_gdbarch_from_file (bfd *abfd)
 628 {
 629   if (GDB_MULTI_ARCH)
 630     {
 631       struct gdbarch_info info;
 632       memset (&info, 0, sizeof info);
 633       info.abfd = abfd;
 634       if (! gdbarch_update_p (info))
 635         error ("Architecture of file not recognized.\n");
 636     }
 637   else
 638     {
 639       set_architecture_from_file (abfd);
 640       set_endian_from_file (abfd);
 641     }
 642 }
 643
 644 /* Initialize the current architecture.  Update the ``set
 645    architecture'' command so that it specifies a list of valid
 646    architectures.  */
 647
 648 #ifdef DEFAULT_BFD_ARCH
 649 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
 650 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
 651 #else
 652 static const bfd_arch_info_type *default_bfd_arch;
 653 #endif
 654
 655 #ifdef DEFAULT_BFD_VEC
 656 extern const bfd_target DEFAULT_BFD_VEC;
 657 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
 658 #else
 659 static const bfd_target *default_bfd_vec;
 660 #endif
 661
 662 void
 663 initialize_current_architecture (void)
 664 {
 665   const char **arches = gdbarch_printable_names ();
 666
 667   /* determine a default architecture and byte order. */
 668   struct gdbarch_info info;
 669   memset (&info, 0, sizeof (info));
 670
 671   /* Find a default architecture. */
 672   if (info.bfd_arch_info == NULL
 673       && default_bfd_arch != NULL)
 674     info.bfd_arch_info = default_bfd_arch;
 675   if (info.bfd_arch_info == NULL)
 676     {
 677       /* Choose the architecture by taking the first one
 678          alphabetically. */
 679       const char *chosen = arches[0];
 680       const char **arch;
 681       for (arch = arches; *arch != NULL; arch++)
 682         {
 683           if (strcmp (*arch, chosen) < 0)
 684             chosen = *arch;
 685         }
 686       if (chosen == NULL)
 687         internal_error (__FILE__, __LINE__,
 688                         "initialize_current_architecture: No arch");
 689       info.bfd_arch_info = bfd_scan_arch (chosen);
 690       if (info.bfd_arch_info == NULL)
 691         internal_error (__FILE__, __LINE__,
 692                         "initialize_current_architecture: Arch not found");
 693     }
 694
 695   /* take several guesses at a byte order. */
 696   /* NB: can't use TARGET_BYTE_ORDER_DEFAULT as its definition is
 697      forced above. */
 698   if (info.byte_order == 0
 699       && default_bfd_vec != NULL)
 700     {
 701       /* Extract BFD's default vector's byte order. */
 702       switch (default_bfd_vec->byteorder)
 703         {
 704         case BFD_ENDIAN_BIG:
 705           info.byte_order = BIG_ENDIAN;
 706           break;
 707         case BFD_ENDIAN_LITTLE:
 708           info.byte_order = LITTLE_ENDIAN;
 709           break;
 710         default:
 711           break;
 712         }
 713     }
 714   if (info.byte_order == 0)
 715     {
 716       /* look for ``*el-*'' in the target name. */
 717       const char *chp;
 718       chp = strchr (target_name, '-');
 719       if (chp != NULL
 720           && chp - 2 >= target_name
 721           && strncmp (chp - 2, "el", 2) == 0)
 722         info.byte_order = LITTLE_ENDIAN;
 723     }
 724   if (info.byte_order == 0)
 725     {
 726       /* Wire it to big-endian!!! */
 727       info.byte_order = BIG_ENDIAN;
 728     }
 729
 730   if (GDB_MULTI_ARCH)
 731     {
 732       if (! gdbarch_update_p (info))
 733         {
 734           internal_error (__FILE__, __LINE__,
 735                           "initialize_current_architecture: Selection of initial architecture failed");
 736         }
 737     }
 738
 739   /* Create the ``set architecture'' command appending ``auto'' to the
 740      list of architectures. */
 741   {
 742     struct cmd_list_element *c;
 743     /* Append ``auto''. */
 744     int nr;
 745     for (nr = 0; arches[nr] != NULL; nr++);
 746     arches = xrealloc (arches, sizeof (char*) * (nr + 2));
 747     arches[nr + 0] = "auto";
 748     arches[nr + 1] = NULL;
 749     /* FIXME: add_set_enum_cmd() uses an array of ``char *'' instead
 750        of ``const char *''.  We just happen to know that the casts are
 751        safe. */
 752     c = add_set_enum_cmd ("architecture", class_support,
 753                           arches, &set_architecture_string,
 754                           "Set architecture of target.",
 755                           &setlist);
 756     c->function.sfunc = set_architecture;
 757     add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
 758     /* Don't use set_from_show - need to print both auto/manual and
 759        current setting. */
 760     add_cmd ("architecture", class_support, show_architecture,
 761              "Show the current target architecture", &showlist);
 762     c = add_cmd ("architecture", class_support, info_architecture,
 763                  "List supported target architectures", &infolist);
 764     deprecate_cmd (c, "set architecture");
 765   }
 766 }
 767
 768
 769 /* */
 770
 771 extern initialize_file_ftype _initialize_gdbarch_utils;
 772
 773 void
 774 _initialize_gdbarch_utils (void)
 775 {
 776   struct cmd_list_element *c;
 777   c = add_set_enum_cmd ("endian", class_support,
 778                         endian_enum, &set_endian_string,
 779                         "Set endianness of target.",
 780                         &setlist);
 781   c->function.sfunc = set_endian;
 782   /* Don't use set_from_show - need to print both auto/manual and
 783      current setting. */
 784   add_cmd ("endian", class_support, show_endian,
 785            "Show the current byte-order", &showlist);
 786 }