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 #include "gdb_assert.h"
  42
  43 #include "version.h"
  44
  45 #include "floatformat.h"
  46
  47 /* Use the program counter to determine the contents and size
  48    of a breakpoint instruction.  If no target-dependent macro
  49    BREAKPOINT_FROM_PC has been defined to implement this function,
  50    assume that the breakpoint doesn't depend on the PC, and
  51    use the values of the BIG_BREAKPOINT and LITTLE_BREAKPOINT macros.
  52    Return a pointer to a string of bytes that encode a breakpoint
  53    instruction, stores the length of the string to *lenptr,
  54    and optionally adjust the pc to point to the correct memory location
  55    for inserting the breakpoint.  */
  56
  57 unsigned char *
  58 legacy_breakpoint_from_pc (CORE_ADDR * pcptr, int *lenptr)
  59 {
  60   /* {BIG_,LITTLE_}BREAKPOINT is the sequence of bytes we insert for a
  61      breakpoint.  On some machines, breakpoints are handled by the
  62      target environment and we don't have to worry about them here.  */
  63 #ifdef BIG_BREAKPOINT
  64   if (TARGET_BYTE_ORDER == BIG_ENDIAN)
  65     {
  66       static unsigned char big_break_insn[] = BIG_BREAKPOINT;
  67       *lenptr = sizeof (big_break_insn);
  68       return big_break_insn;
  69     }
  70 #endif
  71 #ifdef LITTLE_BREAKPOINT
  72   if (TARGET_BYTE_ORDER != BIG_ENDIAN)
  73     {
  74       static unsigned char little_break_insn[] = LITTLE_BREAKPOINT;
  75       *lenptr = sizeof (little_break_insn);
  76       return little_break_insn;
  77     }
  78 #endif
  79 #ifdef BREAKPOINT
  80   {
  81     static unsigned char break_insn[] = BREAKPOINT;
  82     *lenptr = sizeof (break_insn);
  83     return break_insn;
  84   }
  85 #endif
  86   *lenptr = 0;
  87   return NULL;
  88 }
  89
  90 int
  91 generic_frameless_function_invocation_not (struct frame_info *fi)
  92 {
  93   return 0;
  94 }
  95
  96 int
  97 generic_return_value_on_stack_not (struct type *type)
  98 {
  99   return 0;
 100 }
 101
 102 char *
 103 legacy_register_name (int i)
 104 {
 105 #ifdef REGISTER_NAMES
 106   static char *names[] = REGISTER_NAMES;
 107   if (i < 0 || i >= (sizeof (names) / sizeof (*names)))
 108     return NULL;
 109   else
 110     return names[i];
 111 #else
 112   internal_error (__FILE__, __LINE__,
 113                   "legacy_register_name: called.");
 114   return NULL;
 115 #endif
 116 }
 117
 118 #if defined (CALL_DUMMY)
 119 LONGEST legacy_call_dummy_words[] = CALL_DUMMY;
 120 #else
 121 LONGEST legacy_call_dummy_words[1];
 122 #endif
 123 int legacy_sizeof_call_dummy_words = sizeof (legacy_call_dummy_words);
 124
 125 void
 126 generic_remote_translate_xfer_address (CORE_ADDR gdb_addr, int gdb_len,
 127                                        CORE_ADDR * rem_addr, int *rem_len)
 128 {
 129   *rem_addr = gdb_addr;
 130   *rem_len = gdb_len;
 131 }
 132
 133 int
 134 generic_prologue_frameless_p (CORE_ADDR ip)
 135 {
 136 #ifdef SKIP_PROLOGUE_FRAMELESS_P
 137   return ip == SKIP_PROLOGUE_FRAMELESS_P (ip);
 138 #else
 139   return ip == SKIP_PROLOGUE (ip);
 140 #endif
 141 }
 142
 143
 144 /* Helper functions for INNER_THAN */
 145
 146 int
 147 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
 148 {
 149   return (lhs < rhs);
 150 }
 151
 152 int
 153 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
 154 {
 155   return (lhs > rhs);
 156 }
 157
 158
 159 /* Helper functions for TARGET_{FLOAT,DOUBLE}_FORMAT */
 160
 161 const struct floatformat *
 162 default_float_format (struct gdbarch *gdbarch)
 163 {
 164 #if GDB_MULTI_ARCH
 165   int byte_order = gdbarch_byte_order (gdbarch);
 166 #else
 167   int byte_order = TARGET_BYTE_ORDER;
 168 #endif
 169   switch (byte_order)
 170     {
 171     case BIG_ENDIAN:
 172       return &floatformat_ieee_single_big;
 173     case LITTLE_ENDIAN:
 174       return &floatformat_ieee_single_little;
 175     default:
 176       internal_error (__FILE__, __LINE__,
 177                       "default_float_format: bad byte order");
 178     }
 179 }
 180
 181
 182 const struct floatformat *
 183 default_double_format (struct gdbarch *gdbarch)
 184 {
 185 #if GDB_MULTI_ARCH
 186   int byte_order = gdbarch_byte_order (gdbarch);
 187 #else
 188   int byte_order = TARGET_BYTE_ORDER;
 189 #endif
 190   switch (byte_order)
 191     {
 192     case BIG_ENDIAN:
 193       return &floatformat_ieee_double_big;
 194     case LITTLE_ENDIAN:
 195       return &floatformat_ieee_double_little;
 196     default:
 197       internal_error (__FILE__, __LINE__,
 198                       "default_double_format: bad byte order");
 199     }
 200 }
 201
 202 /* Misc helper functions for targets. */
 203
 204 int
 205 frame_num_args_unknown (struct frame_info *fi)
 206 {
 207   return -1;
 208 }
 209
 210
 211 int
 212 generic_register_convertible_not (int num)
 213 {
 214   return 0;
 215 }
 216
 217
 218 int
 219 default_register_sim_regno (int num)
 220 {
 221   return num;
 222 }
 223
 224
 225 CORE_ADDR
 226 core_addr_identity (CORE_ADDR addr)
 227 {
 228   return addr;
 229 }
 230
 231 int
 232 no_op_reg_to_regnum (int reg)
 233 {
 234   return reg;
 235 }
 236
 237 /* For use by frame_args_address and frame_locals_address.  */
 238 CORE_ADDR
 239 default_frame_address (struct frame_info *fi)
 240 {
 241   return fi->frame;
 242 }
 243
 244 /* Default prepare_to_procced().  */
 245 int
 246 default_prepare_to_proceed (int select_it)
 247 {
 248   return 0;
 249 }
 250
 251 /* Generic prepare_to_proceed().  This one should be suitable for most
 252    targets that support threads. */
 253 int
 254 generic_prepare_to_proceed (int select_it)
 255 {
 256   ptid_t wait_ptid;
 257   struct target_waitstatus wait_status;
 258
 259   /* Get the last target status returned by target_wait().  */
 260   get_last_target_status (&wait_ptid, &wait_status);
 261
 262   /* Make sure we were stopped either at a breakpoint, or because
 263      of a Ctrl-C.  */
 264   if (wait_status.kind != TARGET_WAITKIND_STOPPED
 265       || (wait_status.value.sig != TARGET_SIGNAL_TRAP &&
 266           wait_status.value.sig != TARGET_SIGNAL_INT))
 267     {
 268       return 0;
 269     }
 270
 271   if (!ptid_equal (wait_ptid, minus_one_ptid)
 272       && !ptid_equal (inferior_ptid, wait_ptid))
 273     {
 274       /* Switched over from WAIT_PID.  */
 275       CORE_ADDR wait_pc = read_pc_pid (wait_ptid);
 276
 277       if (wait_pc != read_pc ())
 278         {
 279           if (select_it)
 280             {
 281               /* Switch back to WAIT_PID thread.  */
 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           /* We return 1 to indicate that there is a breakpoint here,
 292              so we need to step over it before continuing to avoid
 293              hitting it straight away. */
 294           if (breakpoint_here_p (wait_pc))
 295             {
 296               return 1;
 297             }
 298         }
 299     }
 300   return 0;
 301
 302 }
 303
 304 void
 305 init_frame_pc_noop (int fromleaf, struct frame_info *prev)
 306 {
 307   return;
 308 }
 309
 310 void
 311 init_frame_pc_default (int fromleaf, struct frame_info *prev)
 312 {
 313   if (fromleaf)
 314     prev->pc = SAVED_PC_AFTER_CALL (prev->next);
 315   else if (prev->next != NULL)
 316     prev->pc = FRAME_SAVED_PC (prev->next);
 317   else
 318     prev->pc = read_pc ();
 319 }
 320
 321 int
 322 cannot_register_not (int regnum)
 323 {
 324   return 0;
 325 }
 326
 327 /* Legacy version of target_virtual_frame_pointer().  Assumes that
 328    there is an FP_REGNUM and that it is the same, cooked or raw.  */
 329
 330 void
 331 legacy_virtual_frame_pointer (CORE_ADDR pc,
 332                               int *frame_regnum,
 333                               LONGEST *frame_offset)
 334 {
 335   gdb_assert (FP_REGNUM >= 0);
 336   *frame_regnum = FP_REGNUM;
 337   *frame_offset = 0;
 338 }
 339 \f
 340 /* Functions to manipulate the endianness of the target.  */
 341
 342 #ifdef TARGET_BYTE_ORDER_SELECTABLE
 343 /* compat - Catch old targets that expect a selectable byte-order to
 344    default to BIG_ENDIAN */
 345 #ifndef TARGET_BYTE_ORDER_DEFAULT
 346 #define TARGET_BYTE_ORDER_DEFAULT BIG_ENDIAN
 347 #endif
 348 #endif
 349 #if !TARGET_BYTE_ORDER_SELECTABLE_P
 350 #ifndef TARGET_BYTE_ORDER_DEFAULT
 351 /* compat - Catch old non byte-order selectable targets that do not
 352    define TARGET_BYTE_ORDER_DEFAULT and instead expect
 353    TARGET_BYTE_ORDER to be used as the default.  For targets that
 354    defined neither TARGET_BYTE_ORDER nor TARGET_BYTE_ORDER_DEFAULT the
 355    below will get a strange compiler warning. */
 356 #define TARGET_BYTE_ORDER_DEFAULT TARGET_BYTE_ORDER
 357 #endif
 358 #endif
 359 #ifndef TARGET_BYTE_ORDER_DEFAULT
 360 #define TARGET_BYTE_ORDER_DEFAULT BIG_ENDIAN /* arbitrary */
 361 #endif
 362 /* ``target_byte_order'' is only used when non- multi-arch.
 363    Multi-arch targets obtain the current byte order using
 364    TARGET_BYTE_ORDER which is controlled by gdbarch.*. */
 365 int target_byte_order = TARGET_BYTE_ORDER_DEFAULT;
 366 int target_byte_order_auto = 1;
 367
 368 static const char endian_big[] = "big";
 369 static const char endian_little[] = "little";
 370 static const char endian_auto[] = "auto";
 371 static const char *endian_enum[] =
 372 {
 373   endian_big,
 374   endian_little,
 375   endian_auto,
 376   NULL,
 377 };
 378 static const char *set_endian_string;
 379
 380 /* Called by ``show endian''.  */
 381
 382 static void
 383 show_endian (char *args, int from_tty)
 384 {
 385   if (TARGET_BYTE_ORDER_AUTO)
 386     printf_unfiltered ("The target endianness is set automatically (currently %s endian)\n",
 387                        (TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little"));
 388   else
 389     printf_unfiltered ("The target is assumed to be %s endian\n",
 390                        (TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little"));
 391 }
 392
 393 static void
 394 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
 395 {
 396   if (!TARGET_BYTE_ORDER_SELECTABLE_P)
 397     {
 398       printf_unfiltered ("Byte order is not selectable.");
 399     }
 400   else if (set_endian_string == endian_auto)
 401     {
 402       target_byte_order_auto = 1;
 403     }
 404   else if (set_endian_string == endian_little)
 405     {
 406       target_byte_order_auto = 0;
 407       if (GDB_MULTI_ARCH)
 408         {
 409           struct gdbarch_info info;
 410           memset (&info, 0, sizeof info);
 411           info.byte_order = LITTLE_ENDIAN;
 412           if (! gdbarch_update_p (info))
 413             {
 414               printf_unfiltered ("Little endian target not supported by GDB\n");
 415             }
 416         }
 417       else
 418         {
 419           target_byte_order = LITTLE_ENDIAN;
 420         }
 421     }
 422   else if (set_endian_string == endian_big)
 423     {
 424       target_byte_order_auto = 0;
 425       if (GDB_MULTI_ARCH)
 426         {
 427           struct gdbarch_info info;
 428           memset (&info, 0, sizeof info);
 429           info.byte_order = BIG_ENDIAN;
 430           if (! gdbarch_update_p (info))
 431             {
 432               printf_unfiltered ("Big endian target not supported by GDB\n");
 433             }
 434         }
 435       else
 436         {
 437           target_byte_order = BIG_ENDIAN;
 438         }
 439     }
 440   else
 441     internal_error (__FILE__, __LINE__,
 442                     "set_endian: bad value");
 443   show_endian (NULL, from_tty);
 444 }
 445
 446 /* Set the endianness from a BFD.  */
 447
 448 static void
 449 set_endian_from_file (bfd *abfd)
 450 {
 451   if (GDB_MULTI_ARCH)
 452     internal_error (__FILE__, __LINE__,
 453                     "set_endian_from_file: not for multi-arch");
 454   if (TARGET_BYTE_ORDER_SELECTABLE_P)
 455     {
 456       int want;
 457
 458       if (bfd_big_endian (abfd))
 459         want = BIG_ENDIAN;
 460       else
 461         want = LITTLE_ENDIAN;
 462       if (TARGET_BYTE_ORDER_AUTO)
 463         target_byte_order = want;
 464       else if (TARGET_BYTE_ORDER != want)
 465         warning ("%s endian file does not match %s endian target.",
 466                  want == BIG_ENDIAN ? "big" : "little",
 467                  TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little");
 468     }
 469   else
 470     {
 471       if (bfd_big_endian (abfd)
 472           ? TARGET_BYTE_ORDER != BIG_ENDIAN
 473           : TARGET_BYTE_ORDER == BIG_ENDIAN)
 474         warning ("%s endian file does not match %s endian target.",
 475                  bfd_big_endian (abfd) ? "big" : "little",
 476                  TARGET_BYTE_ORDER == BIG_ENDIAN ? "big" : "little");
 477     }
 478 }
 479
 480
 481 /* Functions to manipulate the architecture of the target */
 482
 483 enum set_arch { set_arch_auto, set_arch_manual };
 484
 485 int target_architecture_auto = 1;
 486
 487 const char *set_architecture_string;
 488
 489 /* Old way of changing the current architecture. */
 490
 491 extern const struct bfd_arch_info bfd_default_arch_struct;
 492 const struct bfd_arch_info *target_architecture = &bfd_default_arch_struct;
 493 int (*target_architecture_hook) (const struct bfd_arch_info *ap);
 494
 495 static int
 496 arch_ok (const struct bfd_arch_info *arch)
 497 {
 498   if (GDB_MULTI_ARCH)
 499     internal_error (__FILE__, __LINE__,
 500                     "arch_ok: not multi-arched");
 501   /* Should be performing the more basic check that the binary is
 502      compatible with GDB. */
 503   /* Check with the target that the architecture is valid. */
 504   return (target_architecture_hook == NULL
 505           || target_architecture_hook (arch));
 506 }
 507
 508 static void
 509 set_arch (const struct bfd_arch_info *arch,
 510           enum set_arch type)
 511 {
 512   if (GDB_MULTI_ARCH)
 513     internal_error (__FILE__, __LINE__,
 514                     "set_arch: not multi-arched");
 515   switch (type)
 516     {
 517     case set_arch_auto:
 518       if (!arch_ok (arch))
 519         warning ("Target may not support %s architecture",
 520                  arch->printable_name);
 521       target_architecture = arch;
 522       break;
 523     case set_arch_manual:
 524       if (!arch_ok (arch))
 525         {
 526           printf_unfiltered ("Target does not support `%s' architecture.\n",
 527                              arch->printable_name);
 528         }
 529       else
 530         {
 531           target_architecture_auto = 0;
 532           target_architecture = arch;
 533         }
 534       break;
 535     }
 536   if (gdbarch_debug)
 537     gdbarch_dump (current_gdbarch, gdb_stdlog);
 538 }
 539
 540 /* Set the architecture from arch/machine (deprecated) */
 541
 542 void
 543 set_architecture_from_arch_mach (enum bfd_architecture arch,
 544                                  unsigned long mach)
 545 {
 546   const struct bfd_arch_info *wanted = bfd_lookup_arch (arch, mach);
 547   if (GDB_MULTI_ARCH)
 548     internal_error (__FILE__, __LINE__,
 549                     "set_architecture_from_arch_mach: not multi-arched");
 550   if (wanted != NULL)
 551     set_arch (wanted, set_arch_manual);
 552   else
 553     internal_error (__FILE__, __LINE__,
 554                     "gdbarch: hardwired architecture/machine not recognized");
 555 }
 556
 557 /* Set the architecture from a BFD (deprecated) */
 558
 559 static void
 560 set_architecture_from_file (bfd *abfd)
 561 {
 562   const struct bfd_arch_info *wanted = bfd_get_arch_info (abfd);
 563   if (GDB_MULTI_ARCH)
 564     internal_error (__FILE__, __LINE__,
 565                     "set_architecture_from_file: not multi-arched");
 566   if (target_architecture_auto)
 567     {
 568       set_arch (wanted, set_arch_auto);
 569     }
 570   else if (wanted != target_architecture)
 571     {
 572       warning ("%s architecture file may be incompatible with %s target.",
 573                wanted->printable_name,
 574                target_architecture->printable_name);
 575     }
 576 }
 577
 578
 579 /* Called if the user enters ``show architecture'' without an
 580    argument. */
 581
 582 static void
 583 show_architecture (char *args, int from_tty)
 584 {
 585   const char *arch;
 586   arch = TARGET_ARCHITECTURE->printable_name;
 587   if (target_architecture_auto)
 588     printf_filtered ("The target architecture is set automatically (currently %s)\n", arch);
 589   else
 590     printf_filtered ("The target architecture is assumed to be %s\n", arch);
 591 }
 592
 593
 594 /* Called if the user enters ``set architecture'' with or without an
 595    argument. */
 596
 597 static void
 598 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
 599 {
 600   if (strcmp (set_architecture_string, "auto") == 0)
 601     {
 602       target_architecture_auto = 1;
 603     }
 604   else if (GDB_MULTI_ARCH)
 605     {
 606       struct gdbarch_info info;
 607       memset (&info, 0, sizeof info);
 608       info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
 609       if (info.bfd_arch_info == NULL)
 610         internal_error (__FILE__, __LINE__,
 611                         "set_architecture: bfd_scan_arch failed");
 612       if (gdbarch_update_p (info))
 613         target_architecture_auto = 0;
 614       else
 615         printf_unfiltered ("Architecture `%s' not recognized.\n",
 616                            set_architecture_string);
 617     }
 618   else
 619     {
 620       const struct bfd_arch_info *arch
 621         = bfd_scan_arch (set_architecture_string);
 622       if (arch == NULL)
 623         internal_error (__FILE__, __LINE__,
 624                         "set_architecture: bfd_scan_arch failed");
 625       set_arch (arch, set_arch_manual);
 626     }
 627   show_architecture (NULL, from_tty);
 628 }
 629
 630 /* Set the dynamic target-system-dependent parameters (architecture,
 631    byte-order) using information found in the BFD */
 632
 633 void
 634 set_gdbarch_from_file (bfd *abfd)
 635 {
 636   if (GDB_MULTI_ARCH)
 637     {
 638       struct gdbarch_info info;
 639       memset (&info, 0, sizeof info);
 640       info.abfd = abfd;
 641       if (! gdbarch_update_p (info))
 642         error ("Architecture of file not recognized.\n");
 643     }
 644   else
 645     {
 646       set_architecture_from_file (abfd);
 647       set_endian_from_file (abfd);
 648     }
 649 }
 650
 651 /* Initialize the current architecture.  Update the ``set
 652    architecture'' command so that it specifies a list of valid
 653    architectures.  */
 654
 655 #ifdef DEFAULT_BFD_ARCH
 656 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
 657 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
 658 #else
 659 static const bfd_arch_info_type *default_bfd_arch;
 660 #endif
 661
 662 #ifdef DEFAULT_BFD_VEC
 663 extern const bfd_target DEFAULT_BFD_VEC;
 664 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
 665 #else
 666 static const bfd_target *default_bfd_vec;
 667 #endif
 668
 669 void
 670 initialize_current_architecture (void)
 671 {
 672   const char **arches = gdbarch_printable_names ();
 673
 674   /* determine a default architecture and byte order. */
 675   struct gdbarch_info info;
 676   memset (&info, 0, sizeof (info));
 677
 678   /* Find a default architecture. */
 679   if (info.bfd_arch_info == NULL
 680       && default_bfd_arch != NULL)
 681     info.bfd_arch_info = default_bfd_arch;
 682   if (info.bfd_arch_info == NULL)
 683     {
 684       /* Choose the architecture by taking the first one
 685          alphabetically. */
 686       const char *chosen = arches[0];
 687       const char **arch;
 688       for (arch = arches; *arch != NULL; arch++)
 689         {
 690           if (strcmp (*arch, chosen) < 0)
 691             chosen = *arch;
 692         }
 693       if (chosen == NULL)
 694         internal_error (__FILE__, __LINE__,
 695                         "initialize_current_architecture: No arch");
 696       info.bfd_arch_info = bfd_scan_arch (chosen);
 697       if (info.bfd_arch_info == NULL)
 698         internal_error (__FILE__, __LINE__,
 699                         "initialize_current_architecture: Arch not found");
 700     }
 701
 702   /* take several guesses at a byte order. */
 703   /* NB: can't use TARGET_BYTE_ORDER_DEFAULT as its definition is
 704      forced above. */
 705   if (info.byte_order == 0
 706       && default_bfd_vec != NULL)
 707     {
 708       /* Extract BFD's default vector's byte order. */
 709       switch (default_bfd_vec->byteorder)
 710         {
 711         case BFD_ENDIAN_BIG:
 712           info.byte_order = BIG_ENDIAN;
 713           break;
 714         case BFD_ENDIAN_LITTLE:
 715           info.byte_order = LITTLE_ENDIAN;
 716           break;
 717         default:
 718           break;
 719         }
 720     }
 721   if (info.byte_order == 0)
 722     {
 723       /* look for ``*el-*'' in the target name. */
 724       const char *chp;
 725       chp = strchr (target_name, '-');
 726       if (chp != NULL
 727           && chp - 2 >= target_name
 728           && strncmp (chp - 2, "el", 2) == 0)
 729         info.byte_order = LITTLE_ENDIAN;
 730     }
 731   if (info.byte_order == 0)
 732     {
 733       /* Wire it to big-endian!!! */
 734       info.byte_order = BIG_ENDIAN;
 735     }
 736
 737   if (GDB_MULTI_ARCH)
 738     {
 739       if (! gdbarch_update_p (info))
 740         {
 741           internal_error (__FILE__, __LINE__,
 742                           "initialize_current_architecture: Selection of initial architecture failed");
 743         }
 744     }
 745   else
 746     initialize_non_multiarch ();
 747
 748   /* Create the ``set architecture'' command appending ``auto'' to the
 749      list of architectures. */
 750   {
 751     struct cmd_list_element *c;
 752     /* Append ``auto''. */
 753     int nr;
 754     for (nr = 0; arches[nr] != NULL; nr++);
 755     arches = xrealloc (arches, sizeof (char*) * (nr + 2));
 756     arches[nr + 0] = "auto";
 757     arches[nr + 1] = NULL;
 758     /* FIXME: add_set_enum_cmd() uses an array of ``char *'' instead
 759        of ``const char *''.  We just happen to know that the casts are
 760        safe. */
 761     c = add_set_enum_cmd ("architecture", class_support,
 762                           arches, &set_architecture_string,
 763                           "Set architecture of target.",
 764                           &setlist);
 765     c->function.sfunc = set_architecture;
 766     add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
 767     /* Don't use set_from_show - need to print both auto/manual and
 768        current setting. */
 769     add_cmd ("architecture", class_support, show_architecture,
 770              "Show the current target architecture", &showlist);
 771   }
 772 }
 773
 774
 775 /* */
 776
 777 extern initialize_file_ftype _initialize_gdbarch_utils;
 778
 779 void
 780 _initialize_gdbarch_utils (void)
 781 {
 782   struct cmd_list_element *c;
 783   c = add_set_enum_cmd ("endian", class_support,
 784                         endian_enum, &set_endian_string,
 785                         "Set endianness of target.",
 786                         &setlist);
 787   c->function.sfunc = set_endian;
 788   /* Don't use set_from_show - need to print both auto/manual and
 789      current setting. */
 790   add_cmd ("endian", class_support, show_endian,
 791            "Show the current byte-order", &showlist);
 792 }