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 /* Helper functions for INNER_THAN */
 147
 148 int
 149 core_addr_lessthan (CORE_ADDR lhs, CORE_ADDR rhs)
 150 {
 151   return (lhs < rhs);
 152 }
 153
 154 int
 155 core_addr_greaterthan (CORE_ADDR lhs, CORE_ADDR rhs)
 156 {
 157   return (lhs > rhs);
 158 }
 159
 160
 161 /* Helper functions for TARGET_{FLOAT,DOUBLE}_FORMAT */
 162
 163 const struct floatformat *
 164 default_float_format (struct gdbarch *gdbarch)
 165 {
 166   int byte_order = gdbarch_byte_order (gdbarch);
 167   switch (byte_order)
 168     {
 169     case BFD_ENDIAN_BIG:
 170       return &floatformat_ieee_single_big;
 171     case BFD_ENDIAN_LITTLE:
 172       return &floatformat_ieee_single_little;
 173     default:
 174       internal_error (__FILE__, __LINE__,
 175                       "default_float_format: bad byte order");
 176     }
 177 }
 178
 179
 180 const struct floatformat *
 181 default_double_format (struct gdbarch *gdbarch)
 182 {
 183   int byte_order = gdbarch_byte_order (gdbarch);
 184   switch (byte_order)
 185     {
 186     case BFD_ENDIAN_BIG:
 187       return &floatformat_ieee_double_big;
 188     case BFD_ENDIAN_LITTLE:
 189       return &floatformat_ieee_double_little;
 190     default:
 191       internal_error (__FILE__, __LINE__,
 192                       "default_double_format: bad byte order");
 193     }
 194 }
 195
 196 /* Misc helper functions for targets. */
 197
 198 CORE_ADDR
 199 core_addr_identity (CORE_ADDR addr)
 200 {
 201   return addr;
 202 }
 203
 204 CORE_ADDR
 205 convert_from_func_ptr_addr_identity (struct gdbarch *gdbarch, CORE_ADDR addr,
 206                                      struct target_ops *targ)
 207 {
 208   return addr;
 209 }
 210
 211 int
 212 no_op_reg_to_regnum (int reg)
 213 {
 214   return reg;
 215 }
 216
 217 CORE_ADDR
 218 deprecated_init_frame_pc_default (int fromleaf, struct frame_info *prev)
 219 {
 220   if (fromleaf && DEPRECATED_SAVED_PC_AFTER_CALL_P ())
 221     return DEPRECATED_SAVED_PC_AFTER_CALL (get_next_frame (prev));
 222   else if (get_next_frame (prev) != NULL)
 223     return DEPRECATED_FRAME_SAVED_PC (get_next_frame (prev));
 224   else
 225     return read_pc ();
 226 }
 227
 228 void
 229 default_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym)
 230 {
 231   return;
 232 }
 233
 234 void
 235 default_coff_make_msymbol_special (int val, struct minimal_symbol *msym)
 236 {
 237   return;
 238 }
 239
 240 int
 241 cannot_register_not (int regnum)
 242 {
 243   return 0;
 244 }
 245
 246 /* Legacy version of target_virtual_frame_pointer().  Assumes that
 247    there is an DEPRECATED_FP_REGNUM and that it is the same, cooked or
 248    raw.  */
 249
 250 void
 251 legacy_virtual_frame_pointer (CORE_ADDR pc,
 252                               int *frame_regnum,
 253                               LONGEST *frame_offset)
 254 {
 255   /* FIXME: cagney/2002-09-13: This code is used when identifying the
 256      frame pointer of the current PC.  It is assuming that a single
 257      register and an offset can determine this.  I think it should
 258      instead generate a byte code expression as that would work better
 259      with things like Dwarf2's CFI.  */
 260   if (DEPRECATED_FP_REGNUM >= 0 && DEPRECATED_FP_REGNUM < NUM_REGS)
 261     *frame_regnum = DEPRECATED_FP_REGNUM;
 262   else if (SP_REGNUM >= 0 && SP_REGNUM < NUM_REGS)
 263     *frame_regnum = SP_REGNUM;
 264   else
 265     /* Should this be an internal error?  I guess so, it is reflecting
 266        an architectural limitation in the current design.  */
 267     internal_error (__FILE__, __LINE__, "No virtual frame pointer available");
 268   *frame_offset = 0;
 269 }
 270
 271 /* Assume the world is sane, every register's virtual and real size
 272    is identical.  */
 273
 274 int
 275 generic_register_size (int regnum)
 276 {
 277   gdb_assert (regnum >= 0 && regnum < NUM_REGS + NUM_PSEUDO_REGS);
 278   if (gdbarch_register_type_p (current_gdbarch))
 279     return TYPE_LENGTH (gdbarch_register_type (current_gdbarch, regnum));
 280   else
 281     /* FIXME: cagney/2003-03-01: Once all architectures implement
 282        gdbarch_register_type(), this entire function can go away.  It
 283        is made obsolete by register_size().  */
 284     return TYPE_LENGTH (DEPRECATED_REGISTER_VIRTUAL_TYPE (regnum)); /* OK */
 285 }
 286
 287 /* Assume all registers are adjacent.  */
 288
 289 int
 290 generic_register_byte (int regnum)
 291 {
 292   int byte;
 293   int i;
 294   gdb_assert (regnum >= 0 && regnum < NUM_REGS + NUM_PSEUDO_REGS);
 295   byte = 0;
 296   for (i = 0; i < regnum; i++)
 297     {
 298       byte += generic_register_size (i);
 299     }
 300   return byte;
 301 }
 302
 303 \f
 304 int
 305 legacy_pc_in_sigtramp (CORE_ADDR pc, char *name)
 306 {
 307 #if !defined (IN_SIGTRAMP)
 308   if (SIGTRAMP_START_P ())
 309     return (pc) >= SIGTRAMP_START (pc) && (pc) < SIGTRAMP_END (pc);
 310   else
 311     return name && strcmp ("_sigtramp", name) == 0;
 312 #else
 313   return IN_SIGTRAMP (pc, name);
 314 #endif
 315 }
 316
 317 int
 318 legacy_convert_register_p (int regnum, struct type *type)
 319 {
 320   return (DEPRECATED_REGISTER_CONVERTIBLE_P ()
 321           && DEPRECATED_REGISTER_CONVERTIBLE (regnum));
 322 }
 323
 324 void
 325 legacy_register_to_value (struct frame_info *frame, int regnum,
 326                           struct type *type, void *to)
 327 {
 328   char from[MAX_REGISTER_SIZE];
 329   get_frame_register (frame, regnum, from);
 330   DEPRECATED_REGISTER_CONVERT_TO_VIRTUAL (regnum, type, from, to);
 331 }
 332
 333 void
 334 legacy_value_to_register (struct frame_info *frame, int regnum,
 335                           struct type *type, const void *tmp)
 336 {
 337   char to[MAX_REGISTER_SIZE];
 338   char *from = alloca (TYPE_LENGTH (type));
 339   memcpy (from, from, TYPE_LENGTH (type));
 340   DEPRECATED_REGISTER_CONVERT_TO_RAW (type, regnum, from, to);
 341   put_frame_register (frame, regnum, to);
 342 }
 343
 344 int
 345 default_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
 346 {
 347   if (DEPRECATED_REG_STRUCT_HAS_ADDR_P ()
 348       && DEPRECATED_REG_STRUCT_HAS_ADDR (processing_gcc_compilation, type))
 349     {
 350       CHECK_TYPEDEF (type);
 351
 352       return (TYPE_CODE (type) == TYPE_CODE_STRUCT
 353               || TYPE_CODE (type) == TYPE_CODE_UNION
 354               || TYPE_CODE (type) == TYPE_CODE_SET
 355               || TYPE_CODE (type) == TYPE_CODE_BITSTRING);
 356     }
 357
 358   return 0;
 359 }
 360
 361 \f
 362 /* Functions to manipulate the endianness of the target.  */
 363
 364 /* ``target_byte_order'' is only used when non- multi-arch.
 365    Multi-arch targets obtain the current byte order using the
 366    TARGET_BYTE_ORDER gdbarch method.
 367
 368    The choice of initial value is entirely arbitrary.  During startup,
 369    the function initialize_current_architecture() updates this value
 370    based on default byte-order information extracted from BFD.  */
 371 static int target_byte_order = BFD_ENDIAN_BIG;
 372 static int target_byte_order_auto = 1;
 373
 374 enum bfd_endian
 375 selected_byte_order (void)
 376 {
 377   if (target_byte_order_auto)
 378     return BFD_ENDIAN_UNKNOWN;
 379   else
 380     return target_byte_order;
 381 }
 382
 383 static const char endian_big[] = "big";
 384 static const char endian_little[] = "little";
 385 static const char endian_auto[] = "auto";
 386 static const char *endian_enum[] =
 387 {
 388   endian_big,
 389   endian_little,
 390   endian_auto,
 391   NULL,
 392 };
 393 static const char *set_endian_string;
 394
 395 /* Called by ``show endian''.  */
 396
 397 static void
 398 show_endian (char *args, int from_tty)
 399 {
 400   if (target_byte_order_auto)
 401     printf_unfiltered ("The target endianness is set automatically (currently %s endian)\n",
 402                        (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG ? "big" : "little"));
 403   else
 404     printf_unfiltered ("The target is assumed to be %s endian\n",
 405                        (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG ? "big" : "little"));
 406 }
 407
 408 static void
 409 set_endian (char *ignore_args, int from_tty, struct cmd_list_element *c)
 410 {
 411   if (set_endian_string == endian_auto)
 412     {
 413       target_byte_order_auto = 1;
 414     }
 415   else if (set_endian_string == endian_little)
 416     {
 417       struct gdbarch_info info;
 418       target_byte_order_auto = 0;
 419       gdbarch_info_init (&info);
 420       info.byte_order = BFD_ENDIAN_LITTLE;
 421       if (! gdbarch_update_p (info))
 422         printf_unfiltered ("Little endian target not supported by GDB\n");
 423     }
 424   else if (set_endian_string == endian_big)
 425     {
 426       struct gdbarch_info info;
 427       target_byte_order_auto = 0;
 428       gdbarch_info_init (&info);
 429       info.byte_order = BFD_ENDIAN_BIG;
 430       if (! gdbarch_update_p (info))
 431         printf_unfiltered ("Big endian target not supported by GDB\n");
 432     }
 433   else
 434     internal_error (__FILE__, __LINE__,
 435                     "set_endian: bad value");
 436   show_endian (NULL, from_tty);
 437 }
 438
 439 /* Functions to manipulate the architecture of the target */
 440
 441 enum set_arch { set_arch_auto, set_arch_manual };
 442
 443 static int target_architecture_auto = 1;
 444
 445 static const char *set_architecture_string;
 446
 447 const char *
 448 selected_architecture_name (void)
 449 {
 450   if (target_architecture_auto)
 451     return NULL;
 452   else
 453     return set_architecture_string;
 454 }
 455
 456 /* Called if the user enters ``show architecture'' without an
 457    argument. */
 458
 459 static void
 460 show_architecture (char *args, int from_tty)
 461 {
 462   const char *arch;
 463   arch = TARGET_ARCHITECTURE->printable_name;
 464   if (target_architecture_auto)
 465     printf_filtered ("The target architecture is set automatically (currently %s)\n", arch);
 466   else
 467     printf_filtered ("The target architecture is assumed to be %s\n", arch);
 468 }
 469
 470
 471 /* Called if the user enters ``set architecture'' with or without an
 472    argument. */
 473
 474 static void
 475 set_architecture (char *ignore_args, int from_tty, struct cmd_list_element *c)
 476 {
 477   if (strcmp (set_architecture_string, "auto") == 0)
 478     {
 479       target_architecture_auto = 1;
 480     }
 481   else
 482     {
 483       struct gdbarch_info info;
 484       gdbarch_info_init (&info);
 485       info.bfd_arch_info = bfd_scan_arch (set_architecture_string);
 486       if (info.bfd_arch_info == NULL)
 487         internal_error (__FILE__, __LINE__,
 488                         "set_architecture: bfd_scan_arch failed");
 489       if (gdbarch_update_p (info))
 490         target_architecture_auto = 0;
 491       else
 492         printf_unfiltered ("Architecture `%s' not recognized.\n",
 493                            set_architecture_string);
 494     }
 495   show_architecture (NULL, from_tty);
 496 }
 497
 498 /* Try to select a global architecture that matches "info".  Return
 499    non-zero if the attempt succeds.  */
 500 int
 501 gdbarch_update_p (struct gdbarch_info info)
 502 {
 503   struct gdbarch *new_gdbarch = gdbarch_find_by_info (info);
 504
 505   /* If there no architecture by that name, reject the request.  */
 506   if (new_gdbarch == NULL)
 507     {
 508       if (gdbarch_debug)
 509         fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
 510                             "Architecture not found\n");
 511       return 0;
 512     }
 513
 514   /* If it is the same old architecture, accept the request (but don't
 515      swap anything).  */
 516   if (new_gdbarch == current_gdbarch)
 517     {
 518       if (gdbarch_debug)
 519         fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
 520                             "Architecture 0x%08lx (%s) unchanged\n",
 521                             (long) new_gdbarch,
 522                             gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
 523       return 1;
 524     }
 525
 526   /* It's a new architecture, swap it in.  */
 527   if (gdbarch_debug)
 528     fprintf_unfiltered (gdb_stdlog, "gdbarch_update_p: "
 529                         "New architecture 0x%08lx (%s) selected\n",
 530                         (long) new_gdbarch,
 531                         gdbarch_bfd_arch_info (new_gdbarch)->printable_name);
 532   deprecated_current_gdbarch_select_hack (new_gdbarch);
 533
 534   return 1;
 535 }
 536
 537 /* Return the architecture for ABFD.  If no suitable architecture
 538    could be find, return NULL.  */
 539
 540 struct gdbarch *
 541 gdbarch_from_bfd (bfd *abfd)
 542 {
 543   struct gdbarch *old_gdbarch = current_gdbarch;
 544   struct gdbarch *new_gdbarch;
 545   struct gdbarch_info info;
 546
 547   gdbarch_info_init (&info);
 548   info.abfd = abfd;
 549   return gdbarch_find_by_info (info);
 550 }
 551
 552 /* Set the dynamic target-system-dependent parameters (architecture,
 553    byte-order) using information found in the BFD */
 554
 555 void
 556 set_gdbarch_from_file (bfd *abfd)
 557 {
 558   struct gdbarch *gdbarch;
 559
 560   gdbarch = gdbarch_from_bfd (abfd);
 561   if (gdbarch == NULL)
 562     error ("Architecture of file not recognized.\n");
 563   deprecated_current_gdbarch_select_hack (gdbarch);
 564 }
 565
 566 /* Initialize the current architecture.  Update the ``set
 567    architecture'' command so that it specifies a list of valid
 568    architectures.  */
 569
 570 #ifdef DEFAULT_BFD_ARCH
 571 extern const bfd_arch_info_type DEFAULT_BFD_ARCH;
 572 static const bfd_arch_info_type *default_bfd_arch = &DEFAULT_BFD_ARCH;
 573 #else
 574 static const bfd_arch_info_type *default_bfd_arch;
 575 #endif
 576
 577 #ifdef DEFAULT_BFD_VEC
 578 extern const bfd_target DEFAULT_BFD_VEC;
 579 static const bfd_target *default_bfd_vec = &DEFAULT_BFD_VEC;
 580 #else
 581 static const bfd_target *default_bfd_vec;
 582 #endif
 583
 584 void
 585 initialize_current_architecture (void)
 586 {
 587   const char **arches = gdbarch_printable_names ();
 588
 589   /* determine a default architecture and byte order. */
 590   struct gdbarch_info info;
 591   gdbarch_info_init (&info);
 592
 593   /* Find a default architecture. */
 594   if (info.bfd_arch_info == NULL
 595       && default_bfd_arch != NULL)
 596     info.bfd_arch_info = default_bfd_arch;
 597   if (info.bfd_arch_info == NULL)
 598     {
 599       /* Choose the architecture by taking the first one
 600          alphabetically. */
 601       const char *chosen = arches[0];
 602       const char **arch;
 603       for (arch = arches; *arch != NULL; arch++)
 604         {
 605           if (strcmp (*arch, chosen) < 0)
 606             chosen = *arch;
 607         }
 608       if (chosen == NULL)
 609         internal_error (__FILE__, __LINE__,
 610                         "initialize_current_architecture: No arch");
 611       info.bfd_arch_info = bfd_scan_arch (chosen);
 612       if (info.bfd_arch_info == NULL)
 613         internal_error (__FILE__, __LINE__,
 614                         "initialize_current_architecture: Arch not found");
 615     }
 616
 617   /* Take several guesses at a byte order.  */
 618   if (info.byte_order == BFD_ENDIAN_UNKNOWN
 619       && default_bfd_vec != NULL)
 620     {
 621       /* Extract BFD's default vector's byte order. */
 622       switch (default_bfd_vec->byteorder)
 623         {
 624         case BFD_ENDIAN_BIG:
 625           info.byte_order = BFD_ENDIAN_BIG;
 626           break;
 627         case BFD_ENDIAN_LITTLE:
 628           info.byte_order = BFD_ENDIAN_LITTLE;
 629           break;
 630         default:
 631           break;
 632         }
 633     }
 634   if (info.byte_order == BFD_ENDIAN_UNKNOWN)
 635     {
 636       /* look for ``*el-*'' in the target name. */
 637       const char *chp;
 638       chp = strchr (target_name, '-');
 639       if (chp != NULL
 640           && chp - 2 >= target_name
 641           && strncmp (chp - 2, "el", 2) == 0)
 642         info.byte_order = BFD_ENDIAN_LITTLE;
 643     }
 644   if (info.byte_order == BFD_ENDIAN_UNKNOWN)
 645     {
 646       /* Wire it to big-endian!!! */
 647       info.byte_order = BFD_ENDIAN_BIG;
 648     }
 649
 650   if (! gdbarch_update_p (info))
 651     internal_error (__FILE__, __LINE__,
 652                     "initialize_current_architecture: Selection of initial architecture failed");
 653
 654   /* Create the ``set architecture'' command appending ``auto'' to the
 655      list of architectures. */
 656   {
 657     struct cmd_list_element *c;
 658     /* Append ``auto''. */
 659     int nr;
 660     for (nr = 0; arches[nr] != NULL; nr++);
 661     arches = xrealloc (arches, sizeof (char*) * (nr + 2));
 662     arches[nr + 0] = "auto";
 663     arches[nr + 1] = NULL;
 664     /* FIXME: add_set_enum_cmd() uses an array of ``char *'' instead
 665        of ``const char *''.  We just happen to know that the casts are
 666        safe. */
 667     c = add_set_enum_cmd ("architecture", class_support,
 668                           arches, &set_architecture_string,
 669                           "Set architecture of target.",
 670                           &setlist);
 671     set_cmd_sfunc (c, set_architecture);
 672     add_alias_cmd ("processor", "architecture", class_support, 1, &setlist);
 673     /* Don't use set_from_show - need to print both auto/manual and
 674        current setting. */
 675     add_cmd ("architecture", class_support, show_architecture,
 676              "Show the current target architecture", &showlist);
 677   }
 678 }
 679
 680
 681 /* Initialize a gdbarch info to values that will be automatically
 682    overridden.  Note: Originally, this ``struct info'' was initialized
 683    using memset(0).  Unfortunately, that ran into problems, namely
 684    BFD_ENDIAN_BIG is zero.  An explicit initialization function that
 685    can explicitly set each field to a well defined value is used.  */
 686
 687 void
 688 gdbarch_info_init (struct gdbarch_info *info)
 689 {
 690   memset (info, 0, sizeof (struct gdbarch_info));
 691   info->byte_order = BFD_ENDIAN_UNKNOWN;
 692   info->osabi = GDB_OSABI_UNINITIALIZED;
 693 }
 694
 695 /* Similar to init, but this time fill in the blanks.  Information is
 696    obtained from the specified architecture, global "set ..." options,
 697    and explicitly initialized INFO fields.  */
 698
 699 void
 700 gdbarch_info_fill (struct gdbarch *gdbarch, struct gdbarch_info *info)
 701 {
 702   /* "(gdb) set architecture ...".  */
 703   if (info->bfd_arch_info == NULL
 704       && !target_architecture_auto
 705       && gdbarch != NULL)
 706     info->bfd_arch_info = gdbarch_bfd_arch_info (gdbarch);
 707   if (info->bfd_arch_info == NULL
 708       && info->abfd != NULL
 709       && bfd_get_arch (info->abfd) != bfd_arch_unknown
 710       && bfd_get_arch (info->abfd) != bfd_arch_obscure)
 711     info->bfd_arch_info = bfd_get_arch_info (info->abfd);
 712   if (info->bfd_arch_info == NULL
 713       && gdbarch != NULL)
 714     info->bfd_arch_info = gdbarch_bfd_arch_info (gdbarch);
 715
 716   /* "(gdb) set byte-order ...".  */
 717   if (info->byte_order == BFD_ENDIAN_UNKNOWN
 718       && !target_byte_order_auto
 719       && gdbarch != NULL)
 720     info->byte_order = gdbarch_byte_order (gdbarch);
 721   /* From the INFO struct.  */
 722   if (info->byte_order == BFD_ENDIAN_UNKNOWN
 723       && info->abfd != NULL)
 724     info->byte_order = (bfd_big_endian (info->abfd) ? BFD_ENDIAN_BIG
 725                        : bfd_little_endian (info->abfd) ? BFD_ENDIAN_LITTLE
 726                        : BFD_ENDIAN_UNKNOWN);
 727   /* From the current target.  */
 728   if (info->byte_order == BFD_ENDIAN_UNKNOWN
 729       && gdbarch != NULL)
 730     info->byte_order = gdbarch_byte_order (gdbarch);
 731
 732   /* "(gdb) set osabi ...".  Handled by gdbarch_lookup_osabi.  */
 733   if (info->osabi == GDB_OSABI_UNINITIALIZED)
 734     info->osabi = gdbarch_lookup_osabi (info->abfd);
 735   if (info->osabi == GDB_OSABI_UNINITIALIZED
 736       && gdbarch != NULL)
 737     info->osabi = gdbarch_osabi (gdbarch);
 738
 739   /* Must have at least filled in the architecture.  */
 740   gdb_assert (info->bfd_arch_info != NULL);
 741 }
 742
 743 /* */
 744
 745 extern initialize_file_ftype _initialize_gdbarch_utils; /* -Wmissing-prototypes */
 746
 747 void
 748 _initialize_gdbarch_utils (void)
 749 {
 750   struct cmd_list_element *c;
 751   c = add_set_enum_cmd ("endian", class_support,
 752                         endian_enum, &set_endian_string,
 753                         "Set endianness of target.",
 754                         &setlist);
 755   set_cmd_sfunc (c, set_endian);
 756   /* Don't use set_from_show - need to print both auto/manual and
 757      current setting. */
 758   add_cmd ("endian", class_support, show_endian,
 759            "Show the current byte-order", &showlist);
 760 }