gdb/arch-utils.c

   1 /* Dynamic architecture support for GDB, the GNU debugger.
   2
   3    Copyright 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation,
   4    Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #include "defs.h"
  24
  25 #include "arch-utils.h"
  26 #include "buildsym.h"
  27 #include "gdbcmd.h"
  28 #include "inferior.h"           /* enum CALL_DUMMY_LOCATION et.al. */
  29 #include "gdb_string.h"
  30 #include "regcache.h"
  31 #include "gdb_assert.h"
  32 #include "sim-regno.h"
  33
  34 #include "osabi.h"
  35
  36 #include "version.h"
  37
  38 #include "floatformat.h"
  39
  40 /* Implementation of extract return value that grubs around in the
  41    register cache.  */
  42 void
  43 legacy_extract_return_value (struct type *type, struct regcache *regcache,
  44                              void *valbuf)
  45 {
  46   char *registers = deprecated_grub_regcache_for_registers (regcache);
  47   bfd_byte *buf = valbuf;
  48   DEPRECATED_EXTRACT_RETURN_VALUE (type, registers, buf); /* OK */
  49 }
  50
  51 /* Implementation of store return value that grubs the register cache.
  52    Takes a local copy of the buffer to avoid const problems.  */
  53 void
  54 legacy_store_return_value (struct type *type, struct regcache *regcache,
  55                            const void *buf)
  56 {
  57   bfd_byte *b = alloca (TYPE_LENGTH (type));
  58   gdb_assert (regcache == current_regcache);
  59   memcpy (b, buf, TYPE_LENGTH (type));
  60   DEPRECATED_STORE_RETURN_VALUE (type, b);
  61 }
  62
  63
  64 int
  65 always_use_struct_convention (int gcc_p, struct type *value_type)
  66 {
  67   return 1;
  68 }
  69
  70
  71 int
  72 legacy_register_sim_regno (int regnum)
  73 {
  74   /* Only makes sense to supply raw registers.  */
  75   gdb_assert (regnum >= 0 && regnum < NUM_REGS);
  76   /* NOTE: cagney/2002-05-13: The old code did it this way and it is
  77      suspected that some GDB/SIM combinations may rely on this
  78      behavour.  The default should be one2one_register_sim_regno
  79      (below).  */
  80   if (REGISTER_NAME (regnum) != NULL
  81       && REGISTER_NAME (regnum)[0] != '\0')
  82     return regnum;
  83   else
  84     return LEGACY_SIM_REGNO_IGNORE;
  85 }
  86
  87 int
  88 generic_frameless_function_invocation_not (struct frame_info *fi)
  89 {
  90   return 0;
  91 }
  92
  93 int
  94 generic_return_value_on_stack_not (struct type *type)
  95 {
  96   return 0;
  97 }
  98
  99 CORE_ADDR
 100 generic_skip_trampoline_code (CORE_ADDR pc)
 101 {
 102   return 0;
 103 }
 104
 105 CORE_ADDR
 106 generic_skip_solib_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
 107 {
 108   return 0;
 109 }
 110
 111 int
 112 generic_in_solib_call_trampoline (CORE_ADDR pc, char *name)
 113 {
 114   return 0;
 115 }
 116
 117 int
 118 generic_in_solib_return_trampoline (CORE_ADDR pc, char *name)
 119 {
 120   return 0;
 121 }
 122
 123 int
 124 generic_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
 125 {
 126   return 0;
 127 }
 128
 129 #if defined (CALL_DUMMY)
 130 LONGEST legacy_call_dummy_words[] = CALL_DUMMY;
 131 #else
 132 LONGEST legacy_call_dummy_words[1];
 133 #endif
 134 int legacy_sizeof_call_dummy_words = sizeof (legacy_call_dummy_words);
 135
 136 void
 137 generic_remote_translate_xfer_address (struct gdbarch *gdbarch,
 138                                        struct regcache *regcache,
 139                                        CORE_ADDR gdb_addr, int gdb_len,
 140                                        CORE_ADDR * rem_addr, int *rem_len)
 141 {
 142   *rem_addr = gdb_addr;
 143   *rem_len = gdb_len;
 144 }
 145
 146 int
 147 generic_prologue_frameless_p (CORE_ADDR ip)
 148 {
 149   return ip == SKIP_PROLOGUE (ip);
 150 }
 151
 152 /* Helper functions for INNER_THAN */
 153
 154 int
 155 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
 156 {
 157   return (lhs < rhs);
 158 }
 159
 160 int
 161 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
 162 {
 163   return (lhs > rhs);
 164 }
 165
 166
 167 /* Helper functions for TARGET_{FLOAT,DOUBLE}_FORMAT */
 168
 169 const struct floatformat *
 170 default_float_format (struct gdbarch *gdbarch)
 171 {
 172   int byte_order = gdbarch_byte_order (gdbarch);
 173   switch (byte_order)
 174     {
 175     case BFD_ENDIAN_BIG:
 176       return &floatformat_ieee_single_big;
 177     case BFD_ENDIAN_LITTLE:
 178       return &floatformat_ieee_single_little;
 179     default:
 180       internal_error (__FILE__, __LINE__,
 181                       "default_float_format: bad byte order");
 182     }
 183 }
 184
 185
 186 const struct floatformat *
 187 default_double_format (struct gdbarch *gdbarch)
 188 {
 189   int byte_order = gdbarch_byte_order (gdbarch);
 190   switch (byte_order)
 191     {
 192     case BFD_ENDIAN_BIG:
 193       return &floatformat_ieee_double_big;
 194     case BFD_ENDIAN_LITTLE:
 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 deprecated_register_convertible_not (int num)
 206 {
 207   return 0;
 208 }
 209
 210
 211 CORE_ADDR
 212 core_addr_identity (CORE_ADDR addr)
 213 {
 214   return addr;
 215 }
 216
 217 CORE_ADDR
 218 convert_from_func_ptr_addr_identity (struct gdbarch *gdbarch, CORE_ADDR addr,
 219                                      struct target_ops *targ)
 220 {
 221   return addr;
 222 }
 223
 224 int
 225 no_op_reg_to_regnum (int reg)
 226 {
 227   return reg;
 228 }
 229
 230 CORE_ADDR
 231 deprecated_init_frame_pc_default (int fromleaf, struct frame_info *prev)
 232 {
 233   if (fromleaf && DEPRECATED_SAVED_PC_AFTER_CALL_P ())
 234     return DEPRECATED_SAVED_PC_AFTER_CALL (get_next_frame (prev));
 235   else if (get_next_frame (prev) != NULL)
 236     return DEPRECATED_FRAME_SAVED_PC (get_next_frame (prev));
 237   else
 238     return read_pc ();
 239 }
 240
 241 void
 242 default_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym)
 243 {
 244   return;
 245 }
 246
 247 void
 248 default_coff_make_msymbol_special (int val, struct minimal_symbol *msym)
 249 {
 250   return;
 251 }
 252
 253 int
 254 cannot_register_not (int regnum)
 255 {
 256   return 0;
 257 }
 258
 259 /* Legacy version of target_virtual_frame_pointer().  Assumes that
 260    there is an DEPRECATED_FP_REGNUM and that it is the same, cooked or
 261    raw.  */
 262
 263 void
 264 legacy_virtual_frame_pointer (CORE_ADDR pc,
 265                               int *frame_regnum,
 266                               LONGEST *frame_offset)
 267 {
 268   /* FIXME: cagney/2002-09-13: This code is used when identifying the
 269      frame pointer of the current PC.  It is assuming that a single
 270      register and an offset can determine this.  I think it should
 271      instead generate a byte code expression as that would work better
 272      with things like Dwarf2's CFI.  */
 273   if (DEPRECATED_FP_REGNUM >= 0 && DEPRECATED_FP_REGNUM < NUM_REGS)
 274     *frame_regnum = DEPRECATED_FP_REGNUM;
 275   else if (SP_REGNUM >= 0 && SP_REGNUM < NUM_REGS)
 276     *frame_regnum = SP_REGNUM;
 277   else
 278     /* Should this be an internal error?  I guess so, it is reflecting
 279        an architectural limitation in the current design.  */
 280     internal_error (__FILE__, __LINE__, "No virtual frame pointer available");
 281   *frame_offset = 0;
 282 }
 283
 284 /* Assume the world is sane, every register's virtual and real size
 285    is identical.  */
 286
 287 int
 288 generic_register_size (int regnum)
 289 {
 290   gdb_assert (regnum >= 0 && regnum < NUM_REGS + NUM_PSEUDO_REGS);
 291   if (gdbarch_register_type_p (current_gdbarch))
 292     return TYPE_LENGTH (gdbarch_register_type (current_gdbarch, regnum));
 293   else
 294     /* FIXME: cagney/2003-03-01: Once all architectures implement
 295        gdbarch_register_type(), this entire function can go away.  It
 296        is made obsolete by register_size().  */
 297     return TYPE_LENGTH (DEPRECATED_REGISTER_VIRTUAL_TYPE (regnum)); /* OK */
 298 }
 299
 300 /* Assume all registers are adjacent.  */
 301
 302 int
 303 generic_register_byte (int regnum)
 304 {
 305   int byte;
 306   int i;
 307   gdb_assert (regnum >= 0 && regnum < NUM_REGS + NUM_PSEUDO_REGS);
 308   byte = 0;
 309   for (i = 0; i < regnum; i++)
 310     {
 311       byte += generic_register_size (i);
 312     }
 313   return byte;
 314 }
 315
 316 \f
 317 int
 318 legacy_pc_in_sigtramp (CORE_ADDR pc, char *name)
 319 {
 320 #if !defined (IN_SIGTRAMP)
 321   if (SIGTRAMP_START_P ())
 322     return (pc) >= SIGTRAMP_START (pc) && (pc) < SIGTRAMP_END (pc);
 323   else
 324     return name && strcmp ("_sigtramp", name) == 0;
 325 #else
 326   return IN_SIGTRAMP (pc, name);
 327 #endif
 328 }
 329
 330 int
 331 legacy_convert_register_p (int regnum, struct type *type)
 332 {
 333   return DEPRECATED_REGISTER_CONVERTIBLE (regnum);
 334 }
 335
 336 void
 337 legacy_register_to_value (struct frame_info *frame, int regnum,
 338                           struct type *type, void *to)
 339 {
 340   char from[MAX_REGISTER_SIZE];
 341   get_frame_register (frame, regnum, from);
 342   DEPRECATED_REGISTER_CONVERT_TO_VIRTUAL (regnum, type, from, to);
 343 }
 344
 345 void
 346 legacy_value_to_register (struct frame_info *frame, int regnum,
 347                           struct type *type, const void *tmp)
 348 {
 349   char to[MAX_REGISTER_SIZE];
 350   char *from = alloca (TYPE_LENGTH (type));
 351   memcpy (from, from, TYPE_LENGTH (type));
 352   DEPRECATED_REGISTER_CONVERT_TO_RAW (type, regnum, from, to);
 353   put_frame_register (frame, regnum, to);
 354 }
 355
 356 int
 357 default_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
 358 {
 359   if (DEPRECATED_REG_STRUCT_HAS_ADDR_P ()
 360       && DEPRECATED_REG_STRUCT_HAS_ADDR (processing_gcc_compilation, type))
 361     {
 362       CHECK_TYPEDEF (type);
 363
 364       return (TYPE_CODE (type) == TYPE_CODE_STRUCT
 365               || TYPE_CODE (type) == TYPE_CODE_UNION
 366               || TYPE_CODE (type) == TYPE_CODE_SET
 367               || TYPE_CODE (type) == TYPE_CODE_BITSTRING);
 368     }
 369
 370   return 0;
 371 }
 372
 373 \f
 374 /* Functions to manipulate the endianness of the target.  */
 375
 376 /* ``target_byte_order'' is only used when non- multi-arch.
 377    Multi-arch targets obtain the current byte order using the
 378    TARGET_BYTE_ORDER gdbarch method.
 379
 380    The choice of initial value is entirely arbitrary.  During startup,
 381    the function initialize_current_architecture() updates this value
 382    based on default byte-order information extracted from BFD.  */
 383 static int target_byte_order = BFD_ENDIAN_BIG;
 384 static int target_byte_order_auto = 1;
 385
 386 enum bfd_endian
 387 selected_byte_order (void)
 388 {
 389   if (target_byte_order_auto)
 390     return BFD_ENDIAN_UNKNOWN;
 391   else
 392     return target_byte_order;
 393 }
 394
 395 static const char endian_big[] = "big";
 396 static const char endian_little[] = "little";
 397 static const char endian_auto[] = "auto";
 398 static const char *endian_enum[] =
 399 {
 400   endian_big,
 401   endian_little,
 402   endian_auto,
 403   NULL,
 404 };
 405 static const char *set_endian_string;
 406
 407 /* Called by ``show endian''.  */
 408
 409 static void
 410 show_endian (char *args, int from_tty)
 411 {
 412   if (target_byte_order_auto)
 413     printf_unfiltered ("The target endianness is set automatically (currently %s endian)\n",
 414                        (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG ? "big" : "little"));
 415   else
 416     printf_unfiltered ("The target is assumed to be %s endian\n",
 417                        (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG ? "big" : "little"));
 418 }
 419
 420 static void
 421 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
 422 {
 423   if (set_endian_string == endian_auto)
 424     {
 425       target_byte_order_auto = 1;
 426     }
 427   else if (set_endian_string == endian_little)
 428     {
 429       struct gdbarch_info info;
 430       target_byte_order_auto = 0;
 431       gdbarch_info_init (&info);
 432       info.byte_order = BFD_ENDIAN_LITTLE;
 433       if (! gdbarch_update_p (info))
 434         printf_unfiltered ("Little endian target not supported by GDB\n");
 435     }
 436   else if (set_endian_string == endian_big)
 437     {
 438       struct gdbarch_info info;
 439       target_byte_order_auto = 0;
 440       gdbarch_info_init (&info);
 441       info.byte_order = BFD_ENDIAN_BIG;
 442       if (! gdbarch_update_p (info))
 443         printf_unfiltered ("Big endian target not supported by GDB\n");
 444     }
 445   else
 446     internal_error (__FILE__, __LINE__,
 447                     "set_endian: bad value");
 448   show_endian (NULL, from_tty);
 449 }
 450
 451 /* Functions to manipulate the architecture of the target */
 452
 453 enum set_arch { set_arch_auto, set_arch_manual };
 454
 455 static int target_architecture_auto = 1;
 456
 457 static const char *set_architecture_string;
 458
 459 const char *
 460 selected_architecture_name (void)
 461 {
 462   if (target_architecture_auto)
 463     return NULL;
 464   else
 465     return set_architecture_string;
 466 }
 467
 468 /* Called if the user enters ``show architecture'' without an
 469    argument. */
 470
 471 static void
 472 show_architecture (char *args, int from_tty)
 473 {
 474   const char *arch;
 475   arch = TARGET_ARCHITECTURE->printable_name;
 476   if (target_architecture_auto)
 477     printf_filtered ("The target architecture is set automatically (currently %s)\n", arch);
 478   else
 479     printf_filtered ("The target architecture is assumed to be %s\n", arch);
 480 }
 481
 482
 483 /* Called if the user enters ``set architecture'' with or without an
 484    argument. */
 485
 486 static void
 487 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
 488 {
 489   if (strcmp (set_architecture_string, "auto") == 0)
 490     {
 491       target_architecture_auto = 1;
 492     }
 493   else
 494     {
 495       struct gdbarch_info info;
 496       gdbarch_info_init (&info);
 497       info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
 498       if (info.bfd_arch_info == NULL)
 499         internal_error (__FILE__, __LINE__,
 500                         "set_architecture: bfd_scan_arch failed");
 501       if (gdbarch_update_p (info))
 502         target_architecture_auto = 0;
 503       else
 504         printf_unfiltered ("Architecture `%s' not recognized.\n",
 505                            set_architecture_string);
 506     }
 507   show_architecture (NULL, from_tty);
 508 }
 509
 510 /* Try to select a global architecture that matches "info".  Return
 511    non-zero if the attempt succeds.  */
 512 int
 513 gdbarch_update_p (struct gdbarch_info info)
 514 {
 515   struct gdbarch *new_gdbarch = gdbarch_find_by_info (info);
 516
 517   /* If there no architecture by that name, reject the request.  */
 518   if (new_gdbarch == NULL)
 519     {
 520       if (gdbarch_debug)
 521         fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
 522                             "Architecture not found\n");
 523       return 0;
 524     }
 525
 526   /* If it is the same old architecture, accept the request (but don't
 527      swap anything).  */
 528   if (new_gdbarch == current_gdbarch)
 529     {
 530       if (gdbarch_debug)
 531         fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
 532                             "Architecture 0x%08lx (%s) unchanged\n",
 533                             (long) new_gdbarch,
 534                             gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
 535       return 1;
 536     }
 537
 538   /* It's a new architecture, swap it in.  */
 539   if (gdbarch_debug)
 540     fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
 541                         "New architecture 0x%08lx (%s) selected\n",
 542                         (long) new_gdbarch,
 543                         gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
 544   deprecated_current_gdbarch_select_hack (new_gdbarch);
 545
 546   return 1;
 547 }
 548
 549 /* Return the architecture for ABFD.  If no suitable architecture
 550    could be find, return NULL.  */
 551
 552 struct gdbarch *
 553 gdbarch_from_bfd (bfd *abfd)
 554 {
 555   struct gdbarch *old_gdbarch = current_gdbarch;
 556   struct gdbarch *new_gdbarch;
 557   struct gdbarch_info info;
 558
 559   gdbarch_info_init (&info);
 560   info.abfd = abfd;
 561   return gdbarch_find_by_info (info);
 562 }
 563
 564 /* Set the dynamic target-system-dependent parameters (architecture,
 565    byte-order) using information found in the BFD */
 566
 567 void
 568 set_gdbarch_from_file (bfd *abfd)
 569 {
 570   struct gdbarch *gdbarch;
 571
 572   gdbarch = gdbarch_from_bfd (abfd);
 573   if (gdbarch == NULL)
 574     error ("Architecture of file not recognized.\n");
 575   deprecated_current_gdbarch_select_hack (gdbarch);
 576 }
 577
 578 /* Initialize the current architecture.  Update the ``set
 579    architecture'' command so that it specifies a list of valid
 580    architectures.  */
 581
 582 #ifdef DEFAULT_BFD_ARCH
 583 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
 584 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
 585 #else
 586 static const bfd_arch_info_type *default_bfd_arch;
 587 #endif
 588
 589 #ifdef DEFAULT_BFD_VEC
 590 extern const bfd_target DEFAULT_BFD_VEC;
 591 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
 592 #else
 593 static const bfd_target *default_bfd_vec;
 594 #endif
 595
 596 void
 597 initialize_current_architecture (void)
 598 {
 599   const char **arches = gdbarch_printable_names ();
 600
 601   /* determine a default architecture and byte order. */
 602   struct gdbarch_info info;
 603   gdbarch_info_init (&info);
 604
 605   /* Find a default architecture. */
 606   if (info.bfd_arch_info == NULL
 607       && default_bfd_arch != NULL)
 608     info.bfd_arch_info = default_bfd_arch;
 609   if (info.bfd_arch_info == NULL)
 610     {
 611       /* Choose the architecture by taking the first one
 612          alphabetically. */
 613       const char *chosen = arches[0];
 614       const char **arch;
 615       for (arch = arches; *arch != NULL; arch++)
 616         {
 617           if (strcmp (*arch, chosen) < 0)
 618             chosen = *arch;
 619         }
 620       if (chosen == NULL)
 621         internal_error (__FILE__, __LINE__,
 622                         "initialize_current_architecture: No arch");
 623       info.bfd_arch_info = bfd_scan_arch (chosen);
 624       if (info.bfd_arch_info == NULL)
 625         internal_error (__FILE__, __LINE__,
 626                         "initialize_current_architecture: Arch not found");
 627     }
 628
 629   /* Take several guesses at a byte order.  */
 630   if (info.byte_order == BFD_ENDIAN_UNKNOWN
 631       && default_bfd_vec != NULL)
 632     {
 633       /* Extract BFD's default vector's byte order. */
 634       switch (default_bfd_vec->byteorder)
 635         {
 636         case BFD_ENDIAN_BIG:
 637           info.byte_order = BFD_ENDIAN_BIG;
 638           break;
 639         case BFD_ENDIAN_LITTLE:
 640           info.byte_order = BFD_ENDIAN_LITTLE;
 641           break;
 642         default:
 643           break;
 644         }
 645     }
 646   if (info.byte_order == BFD_ENDIAN_UNKNOWN)
 647     {
 648       /* look for ``*el-*'' in the target name. */
 649       const char *chp;
 650       chp = strchr (target_name, '-');
 651       if (chp != NULL
 652           && chp - 2 >= target_name
 653           && strncmp (chp - 2, "el", 2) == 0)
 654         info.byte_order = BFD_ENDIAN_LITTLE;
 655     }
 656   if (info.byte_order == BFD_ENDIAN_UNKNOWN)
 657     {
 658       /* Wire it to big-endian!!! */
 659       info.byte_order = BFD_ENDIAN_BIG;
 660     }
 661
 662   if (! gdbarch_update_p (info))
 663     internal_error (__FILE__, __LINE__,
 664                     "initialize_current_architecture: Selection of initial architecture failed");
 665
 666   /* Create the ``set architecture'' command appending ``auto'' to the
 667      list of architectures. */
 668   {
 669     struct cmd_list_element *c;
 670     /* Append ``auto''. */
 671     int nr;
 672     for (nr = 0; arches[nr] != NULL; nr++);
 673     arches = xrealloc (arches, sizeof (char*) * (nr + 2));
 674     arches[nr + 0] = "auto";
 675     arches[nr + 1] = NULL;
 676     /* FIXME: add_set_enum_cmd() uses an array of ``char *'' instead
 677        of ``const char *''.  We just happen to know that the casts are
 678        safe. */
 679     c = add_set_enum_cmd ("architecture", class_support,
 680                           arches, &set_architecture_string,
 681                           "Set architecture of target.",
 682                           &setlist);
 683     set_cmd_sfunc (c, set_architecture);
 684     add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
 685     /* Don't use set_from_show - need to print both auto/manual and
 686        current setting. */
 687     add_cmd ("architecture", class_support, show_architecture,
 688              "Show the current target architecture", &showlist);
 689   }
 690 }
 691
 692
 693 /* Initialize a gdbarch info to values that will be automatically
 694    overridden.  Note: Originally, this ``struct info'' was initialized
 695    using memset(0).  Unfortunately, that ran into problems, namely
 696    BFD_ENDIAN_BIG is zero.  An explicit initialization function that
 697    can explicitly set each field to a well defined value is used.  */
 698
 699 void
 700 gdbarch_info_init (struct gdbarch_info *info)
 701 {
 702   memset (info, 0, sizeof (struct gdbarch_info));
 703   info->byte_order = BFD_ENDIAN_UNKNOWN;
 704   info->osabi = GDB_OSABI_UNINITIALIZED;
 705 }
 706
 707 /* Similar to init, but this time fill in the blanks.  Information is
 708    obtained from the specified architecture, global "set ..." options,
 709    and explicitly initialized INFO fields.  */
 710
 711 void
 712 gdbarch_info_fill (struct gdbarch *gdbarch, struct gdbarch_info *info)
 713 {
 714   /* "(gdb) set architecture ...".  */
 715   if (info->bfd_arch_info == NULL
 716       && !target_architecture_auto
 717       && gdbarch != NULL)
 718     info->bfd_arch_info = gdbarch_bfd_arch_info (gdbarch);
 719   if (info->bfd_arch_info == NULL
 720       && info->abfd != NULL
 721       && bfd_get_arch (info->abfd) != bfd_arch_unknown
 722       && bfd_get_arch (info->abfd) != bfd_arch_obscure)
 723     info->bfd_arch_info = bfd_get_arch_info (info->abfd);
 724   if (info->bfd_arch_info == NULL
 725       && gdbarch != NULL)
 726     info->bfd_arch_info = gdbarch_bfd_arch_info (gdbarch);
 727
 728   /* "(gdb) set byte-order ...".  */
 729   if (info->byte_order == BFD_ENDIAN_UNKNOWN
 730       && !target_byte_order_auto
 731       && gdbarch != NULL)
 732     info->byte_order = gdbarch_byte_order (gdbarch);
 733   /* From the INFO struct.  */
 734   if (info->byte_order == BFD_ENDIAN_UNKNOWN
 735       && info->abfd != NULL)
 736     info->byte_order = (bfd_big_endian (info->abfd) ? BFD_ENDIAN_BIG
 737                        : bfd_little_endian (info->abfd) ? BFD_ENDIAN_LITTLE
 738                        : BFD_ENDIAN_UNKNOWN);
 739   /* From the current target.  */
 740   if (info->byte_order == BFD_ENDIAN_UNKNOWN
 741       && gdbarch != NULL)
 742     info->byte_order = gdbarch_byte_order (gdbarch);
 743
 744   /* "(gdb) set osabi ...".  Handled by gdbarch_lookup_osabi.  */
 745   if (info->osabi == GDB_OSABI_UNINITIALIZED)
 746     info->osabi = gdbarch_lookup_osabi (info->abfd);
 747   if (info->osabi == GDB_OSABI_UNINITIALIZED
 748       && gdbarch != NULL)
 749     info->osabi = gdbarch_osabi (gdbarch);
 750
 751   /* Must have at least filled in the architecture.  */
 752   gdb_assert (info->bfd_arch_info != NULL);
 753 }
 754
 755 /* */
 756
 757 extern initialize_file_ftype _initialize_gdbarch_utils; /* -Wmissing-prototypes */
 758
 759 void
 760 _initialize_gdbarch_utils (void)
 761 {
 762   struct cmd_list_element *c;
 763   c = add_set_enum_cmd ("endian", class_support,
 764                         endian_enum, &set_endian_string,
 765                         "Set endianness of target.",
 766                         &setlist);
 767   set_cmd_sfunc (c, set_endian);
 768   /* Don't use set_from_show - need to print both auto/manual and
 769      current setting. */
 770   add_cmd ("endian", class_support, show_endian,
 771            "Show the current byte-order", &showlist);
 772 }