bfd/reloc.c

   1 /* BFD support for handling relocation entries.
   2    Copyright (C) 1990, 91, 92, 93, 94, 95, 96, 97, 98, 99, 2000
   3    Free Software Foundation, Inc.
   4    Written by Cygnus Support.
   5
   6 This file is part of BFD, the Binary File Descriptor library.
   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, Boston, MA 02111-1307, USA.  */
  21
  22 /*
  23 SECTION
  24         Relocations
  25
  26         BFD maintains relocations in much the same way it maintains
  27         symbols: they are left alone until required, then read in
  28         en-masse and translated into an internal form.  A common
  29         routine <<bfd_perform_relocation>> acts upon the
  30         canonical form to do the fixup.
  31
  32         Relocations are maintained on a per section basis,
  33         while symbols are maintained on a per BFD basis.
  34
  35         All that a back end has to do to fit the BFD interface is to create
  36         a <<struct reloc_cache_entry>> for each relocation
  37         in a particular section, and fill in the right bits of the structures.
  38
  39 @menu
  40 @* typedef arelent::
  41 @* howto manager::
  42 @end menu
  43
  44 */
  45
  46 /* DO compile in the reloc_code name table from libbfd.h.  */
  47 #define _BFD_MAKE_TABLE_bfd_reloc_code_real
  48
  49 #include "bfd.h"
  50 #include "sysdep.h"
  51 #include "bfdlink.h"
  52 #include "libbfd.h"
  53 /*
  54 DOCDD
  55 INODE
  56         typedef arelent, howto manager, Relocations, Relocations
  57
  58 SUBSECTION
  59         typedef arelent
  60
  61         This is the structure of a relocation entry:
  62
  63 CODE_FRAGMENT
  64 .
  65 .typedef enum bfd_reloc_status
  66 .{
  67 .       {* No errors detected *}
  68 .  bfd_reloc_ok,
  69 .
  70 .       {* The relocation was performed, but there was an overflow. *}
  71 .  bfd_reloc_overflow,
  72 .
  73 .       {* The address to relocate was not within the section supplied. *}
  74 .  bfd_reloc_outofrange,
  75 .
  76 .       {* Used by special functions *}
  77 .  bfd_reloc_continue,
  78 .
  79 .       {* Unsupported relocation size requested. *}
  80 .  bfd_reloc_notsupported,
  81 .
  82 .       {* Unused *}
  83 .  bfd_reloc_other,
  84 .
  85 .       {* The symbol to relocate against was undefined. *}
  86 .  bfd_reloc_undefined,
  87 .
  88 .       {* The relocation was performed, but may not be ok - presently
  89 .          generated only when linking i960 coff files with i960 b.out
  90 .          symbols.  If this type is returned, the error_message argument
  91 .          to bfd_perform_relocation will be set.  *}
  92 .  bfd_reloc_dangerous
  93 . }
  94 . bfd_reloc_status_type;
  95 .
  96 .
  97 .typedef struct reloc_cache_entry
  98 .{
  99 .       {* A pointer into the canonical table of pointers  *}
 100 .  struct symbol_cache_entry **sym_ptr_ptr;
 101 .
 102 .       {* offset in section *}
 103 .  bfd_size_type address;
 104 .
 105 .       {* addend for relocation value *}
 106 .  bfd_vma addend;
 107 .
 108 .       {* Pointer to how to perform the required relocation *}
 109 .  reloc_howto_type *howto;
 110 .
 111 .} arelent;
 112
 113 */
 114
 115 /*
 116 DESCRIPTION
 117
 118         Here is a description of each of the fields within an <<arelent>>:
 119
 120         o <<sym_ptr_ptr>>
 121
 122         The symbol table pointer points to a pointer to the symbol
 123         associated with the relocation request.  It is
 124         the pointer into the table returned by the back end's
 125         <<get_symtab>> action. @xref{Symbols}. The symbol is referenced
 126         through a pointer to a pointer so that tools like the linker
 127         can fix up all the symbols of the same name by modifying only
 128         one pointer. The relocation routine looks in the symbol and
 129         uses the base of the section the symbol is attached to and the
 130         value of the symbol as the initial relocation offset. If the
 131         symbol pointer is zero, then the section provided is looked up.
 132
 133         o <<address>>
 134
 135         The <<address>> field gives the offset in bytes from the base of
 136         the section data which owns the relocation record to the first
 137         byte of relocatable information. The actual data relocated
 138         will be relative to this point; for example, a relocation
 139         type which modifies the bottom two bytes of a four byte word
 140         would not touch the first byte pointed to in a big endian
 141         world.
 142
 143         o <<addend>>
 144
 145         The <<addend>> is a value provided by the back end to be added (!)
 146         to the relocation offset. Its interpretation is dependent upon
 147         the howto. For example, on the 68k the code:
 148
 149
 150 |        char foo[];
 151 |        main()
 152 |                {
 153 |                return foo[0x12345678];
 154 |                }
 155
 156         Could be compiled into:
 157
 158 |        linkw fp,#-4
 159 |        moveb @@#12345678,d0
 160 |        extbl d0
 161 |        unlk fp
 162 |        rts
 163
 164
 165         This could create a reloc pointing to <<foo>>, but leave the
 166         offset in the data, something like:
 167
 168
 169 |RELOCATION RECORDS FOR [.text]:
 170 |offset   type      value
 171 |00000006 32        _foo
 172 |
 173 |00000000 4e56 fffc          ; linkw fp,#-4
 174 |00000004 1039 1234 5678     ; moveb @@#12345678,d0
 175 |0000000a 49c0               ; extbl d0
 176 |0000000c 4e5e               ; unlk fp
 177 |0000000e 4e75               ; rts
 178
 179
 180         Using coff and an 88k, some instructions don't have enough
 181         space in them to represent the full address range, and
 182         pointers have to be loaded in two parts. So you'd get something like:
 183
 184
 185 |        or.u     r13,r0,hi16(_foo+0x12345678)
 186 |        ld.b     r2,r13,lo16(_foo+0x12345678)
 187 |        jmp      r1
 188
 189
 190         This should create two relocs, both pointing to <<_foo>>, and with
 191         0x12340000 in their addend field. The data would consist of:
 192
 193
 194 |RELOCATION RECORDS FOR [.text]:
 195 |offset   type      value
 196 |00000002 HVRT16    _foo+0x12340000
 197 |00000006 LVRT16    _foo+0x12340000
 198 |
 199 |00000000 5da05678           ; or.u r13,r0,0x5678
 200 |00000004 1c4d5678           ; ld.b r2,r13,0x5678
 201 |00000008 f400c001           ; jmp r1
 202
 203
 204         The relocation routine digs out the value from the data, adds
 205         it to the addend to get the original offset, and then adds the
 206         value of <<_foo>>. Note that all 32 bits have to be kept around
 207         somewhere, to cope with carry from bit 15 to bit 16.
 208
 209         One further example is the sparc and the a.out format. The
 210         sparc has a similar problem to the 88k, in that some
 211         instructions don't have room for an entire offset, but on the
 212         sparc the parts are created in odd sized lumps. The designers of
 213         the a.out format chose to not use the data within the section
 214         for storing part of the offset; all the offset is kept within
 215         the reloc. Anything in the data should be ignored.
 216
 217 |        save %sp,-112,%sp
 218 |        sethi %hi(_foo+0x12345678),%g2
 219 |        ldsb [%g2+%lo(_foo+0x12345678)],%i0
 220 |        ret
 221 |        restore
 222
 223         Both relocs contain a pointer to <<foo>>, and the offsets
 224         contain junk.
 225
 226
 227 |RELOCATION RECORDS FOR [.text]:
 228 |offset   type      value
 229 |00000004 HI22      _foo+0x12345678
 230 |00000008 LO10      _foo+0x12345678
 231 |
 232 |00000000 9de3bf90     ; save %sp,-112,%sp
 233 |00000004 05000000     ; sethi %hi(_foo+0),%g2
 234 |00000008 f048a000     ; ldsb [%g2+%lo(_foo+0)],%i0
 235 |0000000c 81c7e008     ; ret
 236 |00000010 81e80000     ; restore
 237
 238
 239         o <<howto>>
 240
 241         The <<howto>> field can be imagined as a
 242         relocation instruction. It is a pointer to a structure which
 243         contains information on what to do with all of the other
 244         information in the reloc record and data section. A back end
 245         would normally have a relocation instruction set and turn
 246         relocations into pointers to the correct structure on input -
 247         but it would be possible to create each howto field on demand.
 248
 249 */
 250
 251 /*
 252 SUBSUBSECTION
 253         <<enum complain_overflow>>
 254
 255         Indicates what sort of overflow checking should be done when
 256         performing a relocation.
 257
 258 CODE_FRAGMENT
 259 .
 260 .enum complain_overflow
 261 .{
 262 .       {* Do not complain on overflow. *}
 263 .  complain_overflow_dont,
 264 .
 265 .       {* Complain if the bitfield overflows, whether it is considered
 266 .          as signed or unsigned. *}
 267 .  complain_overflow_bitfield,
 268 .
 269 .       {* Complain if the value overflows when considered as signed
 270 .          number. *}
 271 .  complain_overflow_signed,
 272 .
 273 .       {* Complain if the value overflows when considered as an
 274 .          unsigned number. *}
 275 .  complain_overflow_unsigned
 276 .};
 277
 278 */
 279
 280 /*
 281 SUBSUBSECTION
 282         <<reloc_howto_type>>
 283
 284         The <<reloc_howto_type>> is a structure which contains all the
 285         information that libbfd needs to know to tie up a back end's data.
 286
 287 CODE_FRAGMENT
 288 .struct symbol_cache_entry;             {* Forward declaration *}
 289 .
 290 .struct reloc_howto_struct
 291 .{
 292 .       {*  The type field has mainly a documentary use - the back end can
 293 .           do what it wants with it, though normally the back end's
 294 .           external idea of what a reloc number is stored
 295 .           in this field. For example, a PC relative word relocation
 296 .           in a coff environment has the type 023 - because that's
 297 .           what the outside world calls a R_PCRWORD reloc. *}
 298 .  unsigned int type;
 299 .
 300 .       {*  The value the final relocation is shifted right by. This drops
 301 .           unwanted data from the relocation.  *}
 302 .  unsigned int rightshift;
 303 .
 304 .       {*  The size of the item to be relocated.  This is *not* a
 305 .           power-of-two measure.  To get the number of bytes operated
 306 .           on by a type of relocation, use bfd_get_reloc_size.  *}
 307 .  int size;
 308 .
 309 .       {*  The number of bits in the item to be relocated.  This is used
 310 .           when doing overflow checking.  *}
 311 .  unsigned int bitsize;
 312 .
 313 .       {*  Notes that the relocation is relative to the location in the
 314 .           data section of the addend. The relocation function will
 315 .           subtract from the relocation value the address of the location
 316 .           being relocated. *}
 317 .  boolean pc_relative;
 318 .
 319 .       {*  The bit position of the reloc value in the destination.
 320 .           The relocated value is left shifted by this amount. *}
 321 .  unsigned int bitpos;
 322 .
 323 .       {* What type of overflow error should be checked for when
 324 .          relocating. *}
 325 .  enum complain_overflow complain_on_overflow;
 326 .
 327 .       {* If this field is non null, then the supplied function is
 328 .          called rather than the normal function. This allows really
 329 .          strange relocation methods to be accomodated (e.g., i960 callj
 330 .          instructions). *}
 331 .  bfd_reloc_status_type (*special_function)
 332 .                                   PARAMS ((bfd *abfd,
 333 .                                            arelent *reloc_entry,
 334 .                                            struct symbol_cache_entry *symbol,
 335 .                                            PTR data,
 336 .                                            asection *input_section,
 337 .                                            bfd *output_bfd,
 338 .                                            char **error_message));
 339 .
 340 .       {* The textual name of the relocation type. *}
 341 .  char *name;
 342 .
 343 .       {* Some formats record a relocation addend in the section contents
 344 .          rather than with the relocation.  For ELF formats this is the
 345 .          distinction between USE_REL and USE_RELA (though the code checks
 346 .          for USE_REL == 1/0).  The value of this field is TRUE if the
 347 .          addend is recorded with the section contents; when performing a
 348 .          partial link (ld -r) the section contents (the data) will be
 349 .          modified.  The value of this field is FALSE if addends are
 350 .          recorded with the relocation (in arelent.addend); when performing
 351 .          a partial link the relocation will be modified.
 352 .          All relocations for all ELF USE_RELA targets should set this field
 353 .          to FALSE (values of TRUE should be looked on with suspicion).
 354 .          However, the converse is not true: not all relocations of all ELF
 355 .          USE_REL targets set this field to TRUE.  Why this is so is peculiar
 356 .          to each particular target.  For relocs that aren't used in partial
 357 .          links (e.g. GOT stuff) it doesn't matter what this is set to.  *}
 358 .  boolean partial_inplace;
 359 .
 360 .       {* The src_mask selects which parts of the read in data
 361 .          are to be used in the relocation sum.  E.g., if this was an 8 bit
 362 .          byte of data which we read and relocated, this would be
 363 .          0x000000ff. When we have relocs which have an addend, such as
 364 .          sun4 extended relocs, the value in the offset part of a
 365 .          relocating field is garbage so we never use it. In this case
 366 .          the mask would be 0x00000000. *}
 367 .  bfd_vma src_mask;
 368 .
 369 .       {* The dst_mask selects which parts of the instruction are replaced
 370 .          into the instruction. In most cases src_mask == dst_mask,
 371 .          except in the above special case, where dst_mask would be
 372 .          0x000000ff, and src_mask would be 0x00000000.   *}
 373 .  bfd_vma dst_mask;
 374 .
 375 .       {* When some formats create PC relative instructions, they leave
 376 .          the value of the pc of the place being relocated in the offset
 377 .          slot of the instruction, so that a PC relative relocation can
 378 .          be made just by adding in an ordinary offset (e.g., sun3 a.out).
 379 .          Some formats leave the displacement part of an instruction
 380 .          empty (e.g., m88k bcs); this flag signals the fact.*}
 381 .  boolean pcrel_offset;
 382 .
 383 .};
 384
 385 */
 386
 387 /*
 388 FUNCTION
 389         The HOWTO Macro
 390
 391 DESCRIPTION
 392         The HOWTO define is horrible and will go away.
 393
 394
 395 .#define HOWTO(C, R,S,B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
 396 .  {(unsigned)C,R,S,B, P, BI, O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
 397
 398 DESCRIPTION
 399         And will be replaced with the totally magic way. But for the
 400         moment, we are compatible, so do it this way.
 401
 402
 403 .#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,complain_overflow_dont,FUNCTION, NAME,false,0,0,IN)
 404 .
 405
 406 DESCRIPTION
 407         This is used to fill in an empty howto entry in an array.
 408
 409 .#define EMPTY_HOWTO(C) \
 410 .  HOWTO((C),0,0,0,false,0,complain_overflow_dont,NULL,NULL,false,0,0,false)
 411 .
 412
 413 DESCRIPTION
 414         Helper routine to turn a symbol into a relocation value.
 415
 416 .#define HOWTO_PREPARE(relocation, symbol)      \
 417 .  {                                            \
 418 .  if (symbol != (asymbol *)NULL) {             \
 419 .    if (bfd_is_com_section (symbol->section)) { \
 420 .      relocation = 0;                          \
 421 .    }                                          \
 422 .    else {                                     \
 423 .      relocation = symbol->value;              \
 424 .    }                                          \
 425 .  }                                            \
 426 .}
 427
 428 */
 429
 430 /*
 431 FUNCTION
 432         bfd_get_reloc_size
 433
 434 SYNOPSIS
 435         unsigned int bfd_get_reloc_size (reloc_howto_type *);
 436
 437 DESCRIPTION
 438         For a reloc_howto_type that operates on a fixed number of bytes,
 439         this returns the number of bytes operated on.
 440  */
 441
 442 unsigned int
 443 bfd_get_reloc_size (howto)
 444      reloc_howto_type *howto;
 445 {
 446   switch (howto->size)
 447     {
 448     case 0: return 1;
 449     case 1: return 2;
 450     case 2: return 4;
 451     case 3: return 0;
 452     case 4: return 8;
 453     case 8: return 16;
 454     case -2: return 4;
 455     default: abort ();
 456     }
 457 }
 458
 459 /*
 460 TYPEDEF
 461         arelent_chain
 462
 463 DESCRIPTION
 464
 465         How relocs are tied together in an <<asection>>:
 466
 467 .typedef struct relent_chain {
 468 .  arelent relent;
 469 .  struct   relent_chain *next;
 470 .} arelent_chain;
 471
 472 */
 473
 474 /* N_ONES produces N one bits, without overflowing machine arithmetic.  */
 475 #define N_ONES(n) (((((bfd_vma) 1 << ((n) - 1)) - 1) << 1) | 1)
 476
 477 /*
 478 FUNCTION
 479         bfd_check_overflow
 480
 481 SYNOPSIS
 482         bfd_reloc_status_type
 483                 bfd_check_overflow
 484                         (enum complain_overflow how,
 485                          unsigned int bitsize,
 486                          unsigned int rightshift,
 487                          unsigned int addrsize,
 488                          bfd_vma relocation);
 489
 490 DESCRIPTION
 491         Perform overflow checking on @var{relocation} which has
 492         @var{bitsize} significant bits and will be shifted right by
 493         @var{rightshift} bits, on a machine with addresses containing
 494         @var{addrsize} significant bits.  The result is either of
 495         @code{bfd_reloc_ok} or @code{bfd_reloc_overflow}.
 496
 497 */
 498
 499 bfd_reloc_status_type
 500 bfd_check_overflow (how, bitsize, rightshift, addrsize, relocation)
 501      enum complain_overflow how;
 502      unsigned int bitsize;
 503      unsigned int rightshift;
 504      unsigned int addrsize;
 505      bfd_vma relocation;
 506 {
 507   bfd_vma fieldmask, addrmask, signmask, ss, a;
 508   bfd_reloc_status_type flag = bfd_reloc_ok;
 509
 510   a = relocation;
 511
 512   /* Note: BITSIZE should always be <= ADDRSIZE, but in case it's not,
 513      we'll be permissive: extra bits in the field mask will
 514      automatically extend the address mask for purposes of the
 515      overflow check.  */
 516   fieldmask = N_ONES (bitsize);
 517   addrmask = N_ONES (addrsize) | fieldmask;
 518
 519   switch (how)
 520     {
 521     case complain_overflow_dont:
 522       break;
 523
 524     case complain_overflow_signed:
 525       /* If any sign bits are set, all sign bits must be set.  That
 526          is, A must be a valid negative address after shifting.  */
 527       a = (a & addrmask) >> rightshift;
 528       signmask = ~ (fieldmask >> 1);
 529       ss = a & signmask;
 530       if (ss != 0 && ss != ((addrmask >> rightshift) & signmask))
 531         flag = bfd_reloc_overflow;
 532       break;
 533
 534     case complain_overflow_unsigned:
 535       /* We have an overflow if the address does not fit in the field.  */
 536       a = (a & addrmask) >> rightshift;
 537       if ((a & ~ fieldmask) != 0)
 538         flag = bfd_reloc_overflow;
 539       break;
 540
 541     case complain_overflow_bitfield:
 542       /* Bitfields are sometimes signed, sometimes unsigned.  We
 543          explicitly allow an address wrap too, which means a bitfield
 544          of n bits is allowed to store -2**n to 2**n-1.  Thus overflow
 545          if the value has some, but not all, bits set outside the
 546          field.  */
 547       a >>= rightshift;
 548       ss = a & ~ fieldmask;
 549       if (ss != 0 && ss != (((bfd_vma) -1 >> rightshift) & ~ fieldmask))
 550         flag = bfd_reloc_overflow;
 551       break;
 552
 553     default:
 554       abort ();
 555     }
 556
 557   return flag;
 558 }
 559
 560 /*
 561 FUNCTION
 562         bfd_perform_relocation
 563
 564 SYNOPSIS
 565         bfd_reloc_status_type
 566                 bfd_perform_relocation
 567                         (bfd *abfd,
 568                          arelent *reloc_entry,
 569                          PTR data,
 570                          asection *input_section,
 571                          bfd *output_bfd,
 572                          char **error_message);
 573
 574 DESCRIPTION
 575         If @var{output_bfd} is supplied to this function, the
 576         generated image will be relocatable; the relocations are
 577         copied to the output file after they have been changed to
 578         reflect the new state of the world. There are two ways of
 579         reflecting the results of partial linkage in an output file:
 580         by modifying the output data in place, and by modifying the
 581         relocation record.  Some native formats (e.g., basic a.out and
 582         basic coff) have no way of specifying an addend in the
 583         relocation type, so the addend has to go in the output data.
 584         This is no big deal since in these formats the output data
 585         slot will always be big enough for the addend. Complex reloc
 586         types with addends were invented to solve just this problem.
 587         The @var{error_message} argument is set to an error message if
 588         this return @code{bfd_reloc_dangerous}.
 589
 590 */
 591
 592
 593 bfd_reloc_status_type
 594 bfd_perform_relocation (abfd, reloc_entry, data, input_section, output_bfd,
 595                         error_message)
 596      bfd *abfd;
 597      arelent *reloc_entry;
 598      PTR data;
 599      asection *input_section;
 600      bfd *output_bfd;
 601      char **error_message;
 602 {
 603   bfd_vma relocation;
 604   bfd_reloc_status_type flag = bfd_reloc_ok;
 605   bfd_size_type octets = reloc_entry->address * bfd_octets_per_byte (abfd);
 606   bfd_vma output_base = 0;
 607   reloc_howto_type *howto = reloc_entry->howto;
 608   asection *reloc_target_output_section;
 609   asymbol *symbol;
 610
 611   symbol = *(reloc_entry->sym_ptr_ptr);
 612   if (bfd_is_abs_section (symbol->section)
 613       && output_bfd != (bfd *) NULL)
 614     {
 615       reloc_entry->address += input_section->output_offset;
 616       return bfd_reloc_ok;
 617     }
 618
 619   /* If we are not producing relocateable output, return an error if
 620      the symbol is not defined.  An undefined weak symbol is
 621      considered to have a value of zero (SVR4 ABI, p. 4-27).  */
 622   if (bfd_is_und_section (symbol->section)
 623       && (symbol->flags & BSF_WEAK) == 0
 624       && output_bfd == (bfd *) NULL)
 625     flag = bfd_reloc_undefined;
 626
 627   /* If there is a function supplied to handle this relocation type,
 628      call it.  It'll return `bfd_reloc_continue' if further processing
 629      can be done.  */
 630   if (howto->special_function)
 631     {
 632       bfd_reloc_status_type cont;
 633       cont = howto->special_function (abfd, reloc_entry, symbol, data,
 634                                       input_section, output_bfd,
 635                                       error_message);
 636       if (cont != bfd_reloc_continue)
 637         return cont;
 638     }
 639
 640   /* Is the address of the relocation really within the section?  */
 641   if (reloc_entry->address > input_section->_cooked_size /
 642       bfd_octets_per_byte (abfd))
 643     return bfd_reloc_outofrange;
 644
 645   /* Work out which section the relocation is targetted at and the
 646      initial relocation command value.  */
 647
 648   /* Get symbol value.  (Common symbols are special.)  */
 649   if (bfd_is_com_section (symbol->section))
 650     relocation = 0;
 651   else
 652     relocation = symbol->value;
 653
 654
 655   reloc_target_output_section = symbol->section->output_section;
 656
 657   /* Convert input-section-relative symbol value to absolute.  */
 658   if (output_bfd && howto->partial_inplace == false)
 659     output_base = 0;
 660   else
 661     output_base = reloc_target_output_section->vma;
 662
 663   relocation += output_base + symbol->section->output_offset;
 664
 665   /* Add in supplied addend.  */
 666   relocation += reloc_entry->addend;
 667
 668   /* Here the variable relocation holds the final address of the
 669      symbol we are relocating against, plus any addend.  */
 670
 671   if (howto->pc_relative == true)
 672     {
 673       /* This is a PC relative relocation.  We want to set RELOCATION
 674          to the distance between the address of the symbol and the
 675          location.  RELOCATION is already the address of the symbol.
 676
 677          We start by subtracting the address of the section containing
 678          the location.
 679
 680          If pcrel_offset is set, we must further subtract the position
 681          of the location within the section.  Some targets arrange for
 682          the addend to be the negative of the position of the location
 683          within the section; for example, i386-aout does this.  For
 684          i386-aout, pcrel_offset is false.  Some other targets do not
 685          include the position of the location; for example, m88kbcs,
 686          or ELF.  For those targets, pcrel_offset is true.
 687
 688          If we are producing relocateable output, then we must ensure
 689          that this reloc will be correctly computed when the final
 690          relocation is done.  If pcrel_offset is false we want to wind
 691          up with the negative of the location within the section,
 692          which means we must adjust the existing addend by the change
 693          in the location within the section.  If pcrel_offset is true
 694          we do not want to adjust the existing addend at all.
 695
 696          FIXME: This seems logical to me, but for the case of
 697          producing relocateable output it is not what the code
 698          actually does.  I don't want to change it, because it seems
 699          far too likely that something will break.  */
 700
 701       relocation -=
 702         input_section->output_section->vma + input_section->output_offset;
 703
 704       if (howto->pcrel_offset == true)
 705         relocation -= reloc_entry->address;
 706     }
 707
 708   if (output_bfd != (bfd *) NULL)
 709     {
 710       if (howto->partial_inplace == false)
 711         {
 712           /* This is a partial relocation, and we want to apply the relocation
 713              to the reloc entry rather than the raw data. Modify the reloc
 714              inplace to reflect what we now know.  */
 715           reloc_entry->addend = relocation;
 716           reloc_entry->address += input_section->output_offset;
 717           return flag;
 718         }
 719       else
 720         {
 721           /* This is a partial relocation, but inplace, so modify the
 722              reloc record a bit.
 723
 724              If we've relocated with a symbol with a section, change
 725              into a ref to the section belonging to the symbol.  */
 726
 727           reloc_entry->address += input_section->output_offset;
 728
 729           /* WTF?? */
 730           if (abfd->xvec->flavour == bfd_target_coff_flavour
 731               && strcmp (abfd->xvec->name, "aixcoff-rs6000") != 0
 732               && strcmp (abfd->xvec->name, "aixcoff64-rs6000") != 0
 733               && strcmp (abfd->xvec->name, "xcoff-powermac") != 0
 734               && strcmp (abfd->xvec->name, "coff-Intel-little") != 0
 735               && strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
 736             {
 737 #if 1
 738               /* For m68k-coff, the addend was being subtracted twice during
 739                  relocation with -r.  Removing the line below this comment
 740                  fixes that problem; see PR 2953.
 741
 742 However, Ian wrote the following, regarding removing the line below,
 743 which explains why it is still enabled:  --djm
 744
 745 If you put a patch like that into BFD you need to check all the COFF
 746 linkers.  I am fairly certain that patch will break coff-i386 (e.g.,
 747 SCO); see coff_i386_reloc in coff-i386.c where I worked around the
 748 problem in a different way.  There may very well be a reason that the
 749 code works as it does.
 750
 751 Hmmm.  The first obvious point is that bfd_perform_relocation should
 752 not have any tests that depend upon the flavour.  It's seem like
 753 entirely the wrong place for such a thing.  The second obvious point
 754 is that the current code ignores the reloc addend when producing
 755 relocateable output for COFF.  That's peculiar.  In fact, I really
 756 have no idea what the point of the line you want to remove is.
 757
 758 A typical COFF reloc subtracts the old value of the symbol and adds in
 759 the new value to the location in the object file (if it's a pc
 760 relative reloc it adds the difference between the symbol value and the
 761 location).  When relocating we need to preserve that property.
 762
 763 BFD handles this by setting the addend to the negative of the old
 764 value of the symbol.  Unfortunately it handles common symbols in a
 765 non-standard way (it doesn't subtract the old value) but that's a
 766 different story (we can't change it without losing backward
 767 compatibility with old object files) (coff-i386 does subtract the old
 768 value, to be compatible with existing coff-i386 targets, like SCO).
 769
 770 So everything works fine when not producing relocateable output.  When
 771 we are producing relocateable output, logically we should do exactly
 772 what we do when not producing relocateable output.  Therefore, your
 773 patch is correct.  In fact, it should probably always just set
 774 reloc_entry->addend to 0 for all cases, since it is, in fact, going to
 775 add the value into the object file.  This won't hurt the COFF code,
 776 which doesn't use the addend; I'm not sure what it will do to other
 777 formats (the thing to check for would be whether any formats both use
 778 the addend and set partial_inplace).
 779
 780 When I wanted to make coff-i386 produce relocateable output, I ran
 781 into the problem that you are running into: I wanted to remove that
 782 line.  Rather than risk it, I made the coff-i386 relocs use a special
 783 function; it's coff_i386_reloc in coff-i386.c.  The function
 784 specifically adds the addend field into the object file, knowing that
 785 bfd_perform_relocation is not going to.  If you remove that line, then
 786 coff-i386.c will wind up adding the addend field in twice.  It's
 787 trivial to fix; it just needs to be done.
 788
 789 The problem with removing the line is just that it may break some
 790 working code.  With BFD it's hard to be sure of anything.  The right
 791 way to deal with this is simply to build and test at least all the
 792 supported COFF targets.  It should be straightforward if time and disk
 793 space consuming.  For each target:
 794     1) build the linker
 795     2) generate some executable, and link it using -r (I would
 796        probably use paranoia.o and link against newlib/libc.a, which
 797        for all the supported targets would be available in
 798        /usr/cygnus/progressive/H-host/target/lib/libc.a).
 799     3) make the change to reloc.c
 800     4) rebuild the linker
 801     5) repeat step 2
 802     6) if the resulting object files are the same, you have at least
 803        made it no worse
 804     7) if they are different you have to figure out which version is
 805        right
 806 */
 807               relocation -= reloc_entry->addend;
 808 #endif
 809               reloc_entry->addend = 0;
 810             }
 811           else
 812             {
 813               reloc_entry->addend = relocation;
 814             }
 815         }
 816     }
 817   else
 818     {
 819       reloc_entry->addend = 0;
 820     }
 821
 822   /* FIXME: This overflow checking is incomplete, because the value
 823      might have overflowed before we get here.  For a correct check we
 824      need to compute the value in a size larger than bitsize, but we
 825      can't reasonably do that for a reloc the same size as a host
 826      machine word.
 827      FIXME: We should also do overflow checking on the result after
 828      adding in the value contained in the object file.  */
 829   if (howto->complain_on_overflow != complain_overflow_dont
 830       && flag == bfd_reloc_ok)
 831     flag = bfd_check_overflow (howto->complain_on_overflow,
 832                                howto->bitsize,
 833                                howto->rightshift,
 834                                bfd_arch_bits_per_address (abfd),
 835                                relocation);
 836
 837   /*
 838     Either we are relocating all the way, or we don't want to apply
 839     the relocation to the reloc entry (probably because there isn't
 840     any room in the output format to describe addends to relocs)
 841     */
 842
 843   /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
 844      (OSF version 1.3, compiler version 3.11).  It miscompiles the
 845      following program:
 846
 847      struct str
 848      {
 849        unsigned int i0;
 850      } s = { 0 };
 851
 852      int
 853      main ()
 854      {
 855        unsigned long x;
 856
 857        x = 0x100000000;
 858        x <<= (unsigned long) s.i0;
 859        if (x == 0)
 860          printf ("failed\n");
 861        else
 862          printf ("succeeded (%lx)\n", x);
 863      }
 864      */
 865
 866   relocation >>= (bfd_vma) howto->rightshift;
 867
 868   /* Shift everything up to where it's going to be used */
 869
 870   relocation <<= (bfd_vma) howto->bitpos;
 871
 872   /* Wait for the day when all have the mask in them */
 873
 874   /* What we do:
 875      i instruction to be left alone
 876      o offset within instruction
 877      r relocation offset to apply
 878      S src mask
 879      D dst mask
 880      N ~dst mask
 881      A part 1
 882      B part 2
 883      R result
 884
 885      Do this:
 886      ((  i i i i i o o o o o  from bfd_get<size>
 887      and           S S S S S) to get the size offset we want
 888      +   r r r r r r r r r r) to get the final value to place
 889      and           D D D D D  to chop to right size
 890      -----------------------
 891      =             A A A A A
 892      And this:
 893      (   i i i i i o o o o o  from bfd_get<size>
 894      and N N N N N          ) get instruction
 895      -----------------------
 896      =   B B B B B
 897
 898      And then:
 899      (   B B B B B
 900      or            A A A A A)
 901      -----------------------
 902      =   R R R R R R R R R R  put into bfd_put<size>
 903      */
 904
 905 #define DOIT(x) \
 906   x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) +  relocation) & howto->dst_mask))
 907
 908   switch (howto->size)
 909     {
 910     case 0:
 911       {
 912         char x = bfd_get_8 (abfd, (char *) data + octets);
 913         DOIT (x);
 914         bfd_put_8 (abfd, x, (unsigned char *) data + octets);
 915       }
 916       break;
 917
 918     case 1:
 919       {
 920         short x = bfd_get_16 (abfd, (bfd_byte *) data + octets);
 921         DOIT (x);
 922         bfd_put_16 (abfd, x, (unsigned char *) data + octets);
 923       }
 924       break;
 925     case 2:
 926       {
 927         long x = bfd_get_32 (abfd, (bfd_byte *) data + octets);
 928         DOIT (x);
 929         bfd_put_32 (abfd, x, (bfd_byte *) data + octets);
 930       }
 931       break;
 932     case -2:
 933       {
 934         long x = bfd_get_32 (abfd, (bfd_byte *) data + octets);
 935         relocation = -relocation;
 936         DOIT (x);
 937         bfd_put_32 (abfd, x, (bfd_byte *) data + octets);
 938       }
 939       break;
 940
 941     case -1:
 942       {
 943         long x = bfd_get_16 (abfd, (bfd_byte *) data + octets);
 944         relocation = -relocation;
 945         DOIT (x);
 946         bfd_put_16 (abfd, x, (bfd_byte *) data + octets);
 947       }
 948       break;
 949
 950     case 3:
 951       /* Do nothing */
 952       break;
 953
 954     case 4:
 955 #ifdef BFD64
 956       {
 957         bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data + octets);
 958         DOIT (x);
 959         bfd_put_64 (abfd, x, (bfd_byte *) data + octets);
 960       }
 961 #else
 962       abort ();
 963 #endif
 964       break;
 965     default:
 966       return bfd_reloc_other;
 967     }
 968
 969   return flag;
 970 }
 971
 972 /*
 973 FUNCTION
 974         bfd_install_relocation
 975
 976 SYNOPSIS
 977         bfd_reloc_status_type
 978                 bfd_install_relocation
 979                         (bfd *abfd,
 980                          arelent *reloc_entry,
 981                          PTR data, bfd_vma data_start,
 982                          asection *input_section,
 983                          char **error_message);
 984
 985 DESCRIPTION
 986         This looks remarkably like <<bfd_perform_relocation>>, except it
 987         does not expect that the section contents have been filled in.
 988         I.e., it's suitable for use when creating, rather than applying
 989         a relocation.
 990
 991         For now, this function should be considered reserved for the
 992         assembler.
 993
 994 */
 995
 996
 997 bfd_reloc_status_type
 998 bfd_install_relocation (abfd, reloc_entry, data_start, data_start_offset,
 999                         input_section, error_message)
1000      bfd *abfd;
1001      arelent *reloc_entry;
1002      PTR data_start;
1003      bfd_vma data_start_offset;
1004      asection *input_section;
1005      char **error_message;
1006 {
1007   bfd_vma relocation;
1008   bfd_reloc_status_type flag = bfd_reloc_ok;
1009   bfd_size_type octets = reloc_entry->address * bfd_octets_per_byte (abfd);
1010   bfd_vma output_base = 0;
1011   reloc_howto_type *howto = reloc_entry->howto;
1012   asection *reloc_target_output_section;
1013   asymbol *symbol;
1014   bfd_byte *data;
1015
1016   symbol = *(reloc_entry->sym_ptr_ptr);
1017   if (bfd_is_abs_section (symbol->section))
1018     {
1019       reloc_entry->address += input_section->output_offset;
1020       return bfd_reloc_ok;
1021     }
1022
1023   /* If there is a function supplied to handle this relocation type,
1024      call it.  It'll return `bfd_reloc_continue' if further processing
1025      can be done.  */
1026   if (howto->special_function)
1027     {
1028       bfd_reloc_status_type cont;
1029
1030       /* XXX - The special_function calls haven't been fixed up to deal
1031          with creating new relocations and section contents.  */
1032       cont = howto->special_function (abfd, reloc_entry, symbol,
1033                                       /* XXX - Non-portable! */
1034                                       ((bfd_byte *) data_start
1035                                        - data_start_offset),
1036                                       input_section, abfd, error_message);
1037       if (cont != bfd_reloc_continue)
1038         return cont;
1039     }
1040
1041   /* Is the address of the relocation really within the section?  */
1042   if (reloc_entry->address > input_section->_cooked_size)
1043     return bfd_reloc_outofrange;
1044
1045   /* Work out which section the relocation is targetted at and the
1046      initial relocation command value.  */
1047
1048   /* Get symbol value.  (Common symbols are special.)  */
1049   if (bfd_is_com_section (symbol->section))
1050     relocation = 0;
1051   else
1052     relocation = symbol->value;
1053
1054   reloc_target_output_section = symbol->section->output_section;
1055
1056   /* Convert input-section-relative symbol value to absolute.  */
1057   if (howto->partial_inplace == false)
1058     output_base = 0;
1059   else
1060     output_base = reloc_target_output_section->vma;
1061
1062   relocation += output_base + symbol->section->output_offset;
1063
1064   /* Add in supplied addend.  */
1065   relocation += reloc_entry->addend;
1066
1067   /* Here the variable relocation holds the final address of the
1068      symbol we are relocating against, plus any addend.  */
1069
1070   if (howto->pc_relative == true)
1071     {
1072       /* This is a PC relative relocation.  We want to set RELOCATION
1073          to the distance between the address of the symbol and the
1074          location.  RELOCATION is already the address of the symbol.
1075
1076          We start by subtracting the address of the section containing
1077          the location.
1078
1079          If pcrel_offset is set, we must further subtract the position
1080          of the location within the section.  Some targets arrange for
1081          the addend to be the negative of the position of the location
1082          within the section; for example, i386-aout does this.  For
1083          i386-aout, pcrel_offset is false.  Some other targets do not
1084          include the position of the location; for example, m88kbcs,
1085          or ELF.  For those targets, pcrel_offset is true.
1086
1087          If we are producing relocateable output, then we must ensure
1088          that this reloc will be correctly computed when the final
1089          relocation is done.  If pcrel_offset is false we want to wind
1090          up with the negative of the location within the section,
1091          which means we must adjust the existing addend by the change
1092          in the location within the section.  If pcrel_offset is true
1093          we do not want to adjust the existing addend at all.
1094
1095          FIXME: This seems logical to me, but for the case of
1096          producing relocateable output it is not what the code
1097          actually does.  I don't want to change it, because it seems
1098          far too likely that something will break.  */
1099
1100       relocation -=
1101         input_section->output_section->vma + input_section->output_offset;
1102
1103       if (howto->pcrel_offset == true && howto->partial_inplace == true)
1104         relocation -= reloc_entry->address;
1105     }
1106
1107   if (howto->partial_inplace == false)
1108     {
1109       /* This is a partial relocation, and we want to apply the relocation
1110          to the reloc entry rather than the raw data. Modify the reloc
1111          inplace to reflect what we now know.  */
1112       reloc_entry->addend = relocation;
1113       reloc_entry->address += input_section->output_offset;
1114       return flag;
1115     }
1116   else
1117     {
1118       /* This is a partial relocation, but inplace, so modify the
1119          reloc record a bit.
1120
1121          If we've relocated with a symbol with a section, change
1122          into a ref to the section belonging to the symbol.  */
1123
1124       reloc_entry->address += input_section->output_offset;
1125
1126       /* WTF?? */
1127       if (abfd->xvec->flavour == bfd_target_coff_flavour
1128           && strcmp (abfd->xvec->name, "aixcoff-rs6000") != 0
1129           && strcmp (abfd->xvec->name, "aixcoff64-rs6000") != 0
1130           && strcmp (abfd->xvec->name, "xcoff-powermac") != 0
1131           && strcmp (abfd->xvec->name, "coff-Intel-little") != 0
1132           && strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
1133         {
1134 #if 1
1135 /* For m68k-coff, the addend was being subtracted twice during
1136    relocation with -r.  Removing the line below this comment
1137    fixes that problem; see PR 2953.
1138
1139 However, Ian wrote the following, regarding removing the line below,
1140 which explains why it is still enabled:  --djm
1141
1142 If you put a patch like that into BFD you need to check all the COFF
1143 linkers.  I am fairly certain that patch will break coff-i386 (e.g.,
1144 SCO); see coff_i386_reloc in coff-i386.c where I worked around the
1145 problem in a different way.  There may very well be a reason that the
1146 code works as it does.
1147
1148 Hmmm.  The first obvious point is that bfd_install_relocation should
1149 not have any tests that depend upon the flavour.  It's seem like
1150 entirely the wrong place for such a thing.  The second obvious point
1151 is that the current code ignores the reloc addend when producing
1152 relocateable output for COFF.  That's peculiar.  In fact, I really
1153 have no idea what the point of the line you want to remove is.
1154
1155 A typical COFF reloc subtracts the old value of the symbol and adds in
1156 the new value to the location in the object file (if it's a pc
1157 relative reloc it adds the difference between the symbol value and the
1158 location).  When relocating we need to preserve that property.
1159
1160 BFD handles this by setting the addend to the negative of the old
1161 value of the symbol.  Unfortunately it handles common symbols in a
1162 non-standard way (it doesn't subtract the old value) but that's a
1163 different story (we can't change it without losing backward
1164 compatibility with old object files) (coff-i386 does subtract the old
1165 value, to be compatible with existing coff-i386 targets, like SCO).
1166
1167 So everything works fine when not producing relocateable output.  When
1168 we are producing relocateable output, logically we should do exactly
1169 what we do when not producing relocateable output.  Therefore, your
1170 patch is correct.  In fact, it should probably always just set
1171 reloc_entry->addend to 0 for all cases, since it is, in fact, going to
1172 add the value into the object file.  This won't hurt the COFF code,
1173 which doesn't use the addend; I'm not sure what it will do to other
1174 formats (the thing to check for would be whether any formats both use
1175 the addend and set partial_inplace).
1176
1177 When I wanted to make coff-i386 produce relocateable output, I ran
1178 into the problem that you are running into: I wanted to remove that
1179 line.  Rather than risk it, I made the coff-i386 relocs use a special
1180 function; it's coff_i386_reloc in coff-i386.c.  The function
1181 specifically adds the addend field into the object file, knowing that
1182 bfd_install_relocation is not going to.  If you remove that line, then
1183 coff-i386.c will wind up adding the addend field in twice.  It's
1184 trivial to fix; it just needs to be done.
1185
1186 The problem with removing the line is just that it may break some
1187 working code.  With BFD it's hard to be sure of anything.  The right
1188 way to deal with this is simply to build and test at least all the
1189 supported COFF targets.  It should be straightforward if time and disk
1190 space consuming.  For each target:
1191     1) build the linker
1192     2) generate some executable, and link it using -r (I would
1193        probably use paranoia.o and link against newlib/libc.a, which
1194        for all the supported targets would be available in
1195        /usr/cygnus/progressive/H-host/target/lib/libc.a).
1196     3) make the change to reloc.c
1197     4) rebuild the linker
1198     5) repeat step 2
1199     6) if the resulting object files are the same, you have at least
1200        made it no worse
1201     7) if they are different you have to figure out which version is
1202        right
1203 */
1204           relocation -= reloc_entry->addend;
1205 #endif
1206           reloc_entry->addend = 0;
1207         }
1208       else
1209         {
1210           reloc_entry->addend = relocation;
1211         }
1212     }
1213
1214   /* FIXME: This overflow checking is incomplete, because the value
1215      might have overflowed before we get here.  For a correct check we
1216      need to compute the value in a size larger than bitsize, but we
1217      can't reasonably do that for a reloc the same size as a host
1218      machine word.
1219      FIXME: We should also do overflow checking on the result after
1220      adding in the value contained in the object file.  */
1221   if (howto->complain_on_overflow != complain_overflow_dont)
1222     flag = bfd_check_overflow (howto->complain_on_overflow,
1223                                howto->bitsize,
1224                                howto->rightshift,
1225                                bfd_arch_bits_per_address (abfd),
1226                                relocation);
1227
1228   /*
1229     Either we are relocating all the way, or we don't want to apply
1230     the relocation to the reloc entry (probably because there isn't
1231     any room in the output format to describe addends to relocs)
1232     */
1233
1234   /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
1235      (OSF version 1.3, compiler version 3.11).  It miscompiles the
1236      following program:
1237
1238      struct str
1239      {
1240        unsigned int i0;
1241      } s = { 0 };
1242
1243      int
1244      main ()
1245      {
1246        unsigned long x;
1247
1248        x = 0x100000000;
1249        x <<= (unsigned long) s.i0;
1250        if (x == 0)
1251          printf ("failed\n");
1252        else
1253          printf ("succeeded (%lx)\n", x);
1254      }
1255      */
1256
1257   relocation >>= (bfd_vma) howto->rightshift;
1258
1259   /* Shift everything up to where it's going to be used */
1260
1261   relocation <<= (bfd_vma) howto->bitpos;
1262
1263   /* Wait for the day when all have the mask in them */
1264
1265   /* What we do:
1266      i instruction to be left alone
1267      o offset within instruction
1268      r relocation offset to apply
1269      S src mask
1270      D dst mask
1271      N ~dst mask
1272      A part 1
1273      B part 2
1274      R result
1275
1276      Do this:
1277      ((  i i i i i o o o o o  from bfd_get<size>
1278      and           S S S S S) to get the size offset we want
1279      +   r r r r r r r r r r) to get the final value to place
1280      and           D D D D D  to chop to right size
1281      -----------------------
1282      =             A A A A A
1283      And this:
1284      (   i i i i i o o o o o  from bfd_get<size>
1285      and N N N N N          ) get instruction
1286      -----------------------
1287      =   B B B B B
1288
1289      And then:
1290      (   B B B B B
1291      or            A A A A A)
1292      -----------------------
1293      =   R R R R R R R R R R  put into bfd_put<size>
1294      */
1295
1296 #define DOIT(x) \
1297   x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) +  relocation) & howto->dst_mask))
1298
1299   data = (bfd_byte *) data_start + (octets - data_start_offset);
1300
1301   switch (howto->size)
1302     {
1303     case 0:
1304       {
1305         char x = bfd_get_8 (abfd, (char *) data);
1306         DOIT (x);
1307         bfd_put_8 (abfd, x, (unsigned char *) data);
1308       }
1309       break;
1310
1311     case 1:
1312       {
1313         short x = bfd_get_16 (abfd, (bfd_byte *) data);
1314         DOIT (x);
1315         bfd_put_16 (abfd, x, (unsigned char *) data);
1316       }
1317       break;
1318     case 2:
1319       {
1320         long x = bfd_get_32 (abfd, (bfd_byte *) data);
1321         DOIT (x);
1322         bfd_put_32 (abfd, x, (bfd_byte *) data);
1323       }
1324       break;
1325     case -2:
1326       {
1327         long x = bfd_get_32 (abfd, (bfd_byte *) data);
1328         relocation = -relocation;
1329         DOIT (x);
1330         bfd_put_32 (abfd, x, (bfd_byte *) data);
1331       }
1332       break;
1333
1334     case 3:
1335       /* Do nothing */
1336       break;
1337
1338     case 4:
1339       {
1340         bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data);
1341         DOIT (x);
1342         bfd_put_64 (abfd, x, (bfd_byte *) data);
1343       }
1344       break;
1345     default:
1346       return bfd_reloc_other;
1347     }
1348
1349   return flag;
1350 }
1351
1352 /* This relocation routine is used by some of the backend linkers.
1353    They do not construct asymbol or arelent structures, so there is no
1354    reason for them to use bfd_perform_relocation.  Also,
1355    bfd_perform_relocation is so hacked up it is easier to write a new
1356    function than to try to deal with it.
1357
1358    This routine does a final relocation.  Whether it is useful for a
1359    relocateable link depends upon how the object format defines
1360    relocations.
1361
1362    FIXME: This routine ignores any special_function in the HOWTO,
1363    since the existing special_function values have been written for
1364    bfd_perform_relocation.
1365
1366    HOWTO is the reloc howto information.
1367    INPUT_BFD is the BFD which the reloc applies to.
1368    INPUT_SECTION is the section which the reloc applies to.
1369    CONTENTS is the contents of the section.
1370    ADDRESS is the address of the reloc within INPUT_SECTION.
1371    VALUE is the value of the symbol the reloc refers to.
1372    ADDEND is the addend of the reloc.  */
1373
1374 bfd_reloc_status_type
1375 _bfd_final_link_relocate (howto, input_bfd, input_section, contents, address,
1376                           value, addend)
1377      reloc_howto_type *howto;
1378      bfd *input_bfd;
1379      asection *input_section;
1380      bfd_byte *contents;
1381      bfd_vma address;
1382      bfd_vma value;
1383      bfd_vma addend;
1384 {
1385   bfd_vma relocation;
1386
1387   /* Sanity check the address.  */
1388   if (address > input_section->_raw_size)
1389     return bfd_reloc_outofrange;
1390
1391   /* This function assumes that we are dealing with a basic relocation
1392      against a symbol.  We want to compute the value of the symbol to
1393      relocate to.  This is just VALUE, the value of the symbol, plus
1394      ADDEND, any addend associated with the reloc.  */
1395   relocation = value + addend;
1396
1397   /* If the relocation is PC relative, we want to set RELOCATION to
1398      the distance between the symbol (currently in RELOCATION) and the
1399      location we are relocating.  Some targets (e.g., i386-aout)
1400      arrange for the contents of the section to be the negative of the
1401      offset of the location within the section; for such targets
1402      pcrel_offset is false.  Other targets (e.g., m88kbcs or ELF)
1403      simply leave the contents of the section as zero; for such
1404      targets pcrel_offset is true.  If pcrel_offset is false we do not
1405      need to subtract out the offset of the location within the
1406      section (which is just ADDRESS).  */
1407   if (howto->pc_relative)
1408     {
1409       relocation -= (input_section->output_section->vma
1410                      + input_section->output_offset);
1411       if (howto->pcrel_offset)
1412         relocation -= address;
1413     }
1414
1415   return _bfd_relocate_contents (howto, input_bfd, relocation,
1416                                  contents + address);
1417 }
1418
1419 /* Relocate a given location using a given value and howto.  */
1420
1421 bfd_reloc_status_type
1422 _bfd_relocate_contents (howto, input_bfd, relocation, location)
1423      reloc_howto_type *howto;
1424      bfd *input_bfd;
1425      bfd_vma relocation;
1426      bfd_byte *location;
1427 {
1428   int size;
1429   bfd_vma x = 0;
1430   bfd_reloc_status_type flag;
1431   unsigned int rightshift = howto->rightshift;
1432   unsigned int bitpos = howto->bitpos;
1433
1434   /* If the size is negative, negate RELOCATION.  This isn't very
1435      general.  */
1436   if (howto->size < 0)
1437     relocation = -relocation;
1438
1439   /* Get the value we are going to relocate.  */
1440   size = bfd_get_reloc_size (howto);
1441   switch (size)
1442     {
1443     default:
1444     case 0:
1445       abort ();
1446     case 1:
1447       x = bfd_get_8 (input_bfd, location);
1448       break;
1449     case 2:
1450       x = bfd_get_16 (input_bfd, location);
1451       break;
1452     case 4:
1453       x = bfd_get_32 (input_bfd, location);
1454       break;
1455     case 8:
1456 #ifdef BFD64
1457       x = bfd_get_64 (input_bfd, location);
1458 #else
1459       abort ();
1460 #endif
1461       break;
1462     }
1463
1464   /* Check for overflow.  FIXME: We may drop bits during the addition
1465      which we don't check for.  We must either check at every single
1466      operation, which would be tedious, or we must do the computations
1467      in a type larger than bfd_vma, which would be inefficient.  */
1468   flag = bfd_reloc_ok;
1469   if (howto->complain_on_overflow != complain_overflow_dont)
1470     {
1471       bfd_vma addrmask, fieldmask, signmask, ss;
1472       bfd_vma a, b, sum;
1473
1474       /* Get the values to be added together.  For signed and unsigned
1475          relocations, we assume that all values should be truncated to
1476          the size of an address.  For bitfields, all the bits matter.
1477          See also bfd_check_overflow.  */
1478       fieldmask = N_ONES (howto->bitsize);
1479       addrmask = N_ONES (bfd_arch_bits_per_address (input_bfd)) | fieldmask;
1480       a = relocation;
1481       b = x & howto->src_mask;
1482
1483       switch (howto->complain_on_overflow)
1484         {
1485         case complain_overflow_signed:
1486           a = (a & addrmask) >> rightshift;
1487
1488           /* If any sign bits are set, all sign bits must be set.
1489              That is, A must be a valid negative address after
1490              shifting.  */
1491           signmask = ~ (fieldmask >> 1);
1492           ss = a & signmask;
1493           if (ss != 0 && ss != ((addrmask >> rightshift) & signmask))
1494             flag = bfd_reloc_overflow;
1495
1496           /* We only need this next bit of code if the sign bit of B
1497              is below the sign bit of A.  This would only happen if
1498              SRC_MASK had fewer bits than BITSIZE.  Note that if
1499              SRC_MASK has more bits than BITSIZE, we can get into
1500              trouble; we would need to verify that B is in range, as
1501              we do for A above.  */
1502           signmask = ((~ howto->src_mask) >> 1) & howto->src_mask;
1503
1504           /* Set all the bits above the sign bit.  */
1505           b = (b ^ signmask) - signmask;
1506
1507           b = (b & addrmask) >> bitpos;
1508
1509           /* Now we can do the addition.  */
1510           sum = a + b;
1511
1512           /* See if the result has the correct sign.  Bits above the
1513              sign bit are junk now; ignore them.  If the sum is
1514              positive, make sure we did not have all negative inputs;
1515              if the sum is negative, make sure we did not have all
1516              positive inputs.  The test below looks only at the sign
1517              bits, and it really just
1518                  SIGN (A) == SIGN (B) && SIGN (A) != SIGN (SUM)
1519              */
1520           signmask = (fieldmask >> 1) + 1;
1521           if (((~ (a ^ b)) & (a ^ sum)) & signmask)
1522             flag = bfd_reloc_overflow;
1523
1524           break;
1525
1526         case complain_overflow_unsigned:
1527           /* Checking for an unsigned overflow is relatively easy:
1528              trim the addresses and add, and trim the result as well.
1529              Overflow is normally indicated when the result does not
1530              fit in the field.  However, we also need to consider the
1531              case when, e.g., fieldmask is 0x7fffffff or smaller, an
1532              input is 0x80000000, and bfd_vma is only 32 bits; then we
1533              will get sum == 0, but there is an overflow, since the
1534              inputs did not fit in the field.  Instead of doing a
1535              separate test, we can check for this by or-ing in the
1536              operands when testing for the sum overflowing its final
1537              field.  */
1538           a = (a & addrmask) >> rightshift;
1539           b = (b & addrmask) >> bitpos;
1540           sum = (a + b) & addrmask;
1541           if ((a | b | sum) & ~ fieldmask)
1542             flag = bfd_reloc_overflow;
1543
1544           break;
1545
1546         case complain_overflow_bitfield:
1547           /* Much like the signed check, but for a field one bit
1548              wider, and no trimming inputs with addrmask.  We allow a
1549              bitfield to represent numbers in the range -2**n to
1550              2**n-1, where n is the number of bits in the field.
1551              Note that when bfd_vma is 32 bits, a 32-bit reloc can't
1552              overflow, which is exactly what we want.  */
1553           a >>= rightshift;
1554
1555           signmask = ~ fieldmask;
1556           ss = a & signmask;
1557           if (ss != 0 && ss != (((bfd_vma) -1 >> rightshift) & signmask))
1558             flag = bfd_reloc_overflow;
1559
1560           signmask = ((~ howto->src_mask) >> 1) & howto->src_mask;
1561           b = (b ^ signmask) - signmask;
1562
1563           b >>= bitpos;
1564
1565           sum = a + b;
1566
1567           /* We mask with addrmask here to explicitly allow an address
1568              wrap-around.  The Linux kernel relies on it, and it is
1569              the only way to write assembler code which can run when
1570              loaded at a location 0x80000000 away from the location at
1571              which it is linked.  */
1572           signmask = fieldmask + 1;
1573           if (((~ (a ^ b)) & (a ^ sum)) & signmask & addrmask)
1574             flag = bfd_reloc_overflow;
1575
1576           break;
1577
1578         default:
1579           abort ();
1580         }
1581     }
1582
1583   /* Put RELOCATION in the right bits.  */
1584   relocation >>= (bfd_vma) rightshift;
1585   relocation <<= (bfd_vma) bitpos;
1586
1587   /* Add RELOCATION to the right bits of X.  */
1588   x = ((x & ~howto->dst_mask)
1589        | (((x & howto->src_mask) + relocation) & howto->dst_mask));
1590
1591   /* Put the relocated value back in the object file.  */
1592   switch (size)
1593     {
1594     default:
1595     case 0:
1596       abort ();
1597     case 1:
1598       bfd_put_8 (input_bfd, x, location);
1599       break;
1600     case 2:
1601       bfd_put_16 (input_bfd, x, location);
1602       break;
1603     case 4:
1604       bfd_put_32 (input_bfd, x, location);
1605       break;
1606     case 8:
1607 #ifdef BFD64
1608       bfd_put_64 (input_bfd, x, location);
1609 #else
1610       abort ();
1611 #endif
1612       break;
1613     }
1614
1615   return flag;
1616 }
1617
1618 /*
1619 DOCDD
1620 INODE
1621         howto manager,  , typedef arelent, Relocations
1622
1623 SECTION
1624         The howto manager
1625
1626         When an application wants to create a relocation, but doesn't
1627         know what the target machine might call it, it can find out by
1628         using this bit of code.
1629
1630 */
1631
1632 /*
1633 TYPEDEF
1634         bfd_reloc_code_type
1635
1636 DESCRIPTION
1637         The insides of a reloc code.  The idea is that, eventually, there
1638         will be one enumerator for every type of relocation we ever do.
1639         Pass one of these values to <<bfd_reloc_type_lookup>>, and it'll
1640         return a howto pointer.
1641
1642         This does mean that the application must determine the correct
1643         enumerator value; you can't get a howto pointer from a random set
1644         of attributes.
1645
1646 SENUM
1647    bfd_reloc_code_real
1648
1649 ENUM
1650   BFD_RELOC_64
1651 ENUMX
1652   BFD_RELOC_32
1653 ENUMX
1654   BFD_RELOC_26
1655 ENUMX
1656   BFD_RELOC_24
1657 ENUMX
1658   BFD_RELOC_16
1659 ENUMX
1660   BFD_RELOC_14
1661 ENUMX
1662   BFD_RELOC_8
1663 ENUMDOC
1664   Basic absolute relocations of N bits.
1665
1666 ENUM
1667   BFD_RELOC_64_PCREL
1668 ENUMX
1669   BFD_RELOC_32_PCREL
1670 ENUMX
1671   BFD_RELOC_24_PCREL
1672 ENUMX
1673   BFD_RELOC_16_PCREL
1674 ENUMX
1675   BFD_RELOC_12_PCREL
1676 ENUMX
1677   BFD_RELOC_8_PCREL
1678 ENUMDOC
1679   PC-relative relocations.  Sometimes these are relative to the address
1680 of the relocation itself; sometimes they are relative to the start of
1681 the section containing the relocation.  It depends on the specific target.
1682
1683 The 24-bit relocation is used in some Intel 960 configurations.
1684
1685 ENUM
1686   BFD_RELOC_32_GOT_PCREL
1687 ENUMX
1688   BFD_RELOC_16_GOT_PCREL
1689 ENUMX
1690   BFD_RELOC_8_GOT_PCREL
1691 ENUMX
1692   BFD_RELOC_32_GOTOFF
1693 ENUMX
1694   BFD_RELOC_16_GOTOFF
1695 ENUMX
1696   BFD_RELOC_LO16_GOTOFF
1697 ENUMX
1698   BFD_RELOC_HI16_GOTOFF
1699 ENUMX
1700   BFD_RELOC_HI16_S_GOTOFF
1701 ENUMX
1702   BFD_RELOC_8_GOTOFF
1703 ENUMX
1704   BFD_RELOC_32_PLT_PCREL
1705 ENUMX
1706   BFD_RELOC_24_PLT_PCREL
1707 ENUMX
1708   BFD_RELOC_16_PLT_PCREL
1709 ENUMX
1710   BFD_RELOC_8_PLT_PCREL
1711 ENUMX
1712   BFD_RELOC_32_PLTOFF
1713 ENUMX
1714   BFD_RELOC_16_PLTOFF
1715 ENUMX
1716   BFD_RELOC_LO16_PLTOFF
1717 ENUMX
1718   BFD_RELOC_HI16_PLTOFF
1719 ENUMX
1720   BFD_RELOC_HI16_S_PLTOFF
1721 ENUMX
1722   BFD_RELOC_8_PLTOFF
1723 ENUMDOC
1724   For ELF.
1725
1726 ENUM
1727   BFD_RELOC_68K_GLOB_DAT
1728 ENUMX
1729   BFD_RELOC_68K_JMP_SLOT
1730 ENUMX
1731   BFD_RELOC_68K_RELATIVE
1732 ENUMDOC
1733   Relocations used by 68K ELF.
1734
1735 ENUM
1736   BFD_RELOC_32_BASEREL
1737 ENUMX
1738   BFD_RELOC_16_BASEREL
1739 ENUMX
1740   BFD_RELOC_LO16_BASEREL
1741 ENUMX
1742   BFD_RELOC_HI16_BASEREL
1743 ENUMX
1744   BFD_RELOC_HI16_S_BASEREL
1745 ENUMX
1746   BFD_RELOC_8_BASEREL
1747 ENUMX
1748   BFD_RELOC_RVA
1749 ENUMDOC
1750   Linkage-table relative.
1751
1752 ENUM
1753   BFD_RELOC_8_FFnn
1754 ENUMDOC
1755   Absolute 8-bit relocation, but used to form an address like 0xFFnn.
1756
1757 ENUM
1758   BFD_RELOC_32_PCREL_S2
1759 ENUMX
1760   BFD_RELOC_16_PCREL_S2
1761 ENUMX
1762   BFD_RELOC_23_PCREL_S2
1763 ENUMDOC
1764   These PC-relative relocations are stored as word displacements --
1765 i.e., byte displacements shifted right two bits.  The 30-bit word
1766 displacement (<<32_PCREL_S2>> -- 32 bits, shifted 2) is used on the
1767 SPARC.  (SPARC tools generally refer to this as <<WDISP30>>.)  The
1768 signed 16-bit displacement is used on the MIPS, and the 23-bit
1769 displacement is used on the Alpha.
1770
1771 ENUM
1772   BFD_RELOC_HI22
1773 ENUMX
1774   BFD_RELOC_LO10
1775 ENUMDOC
1776   High 22 bits and low 10 bits of 32-bit value, placed into lower bits of
1777 the target word.  These are used on the SPARC.
1778
1779 ENUM
1780   BFD_RELOC_GPREL16
1781 ENUMX
1782   BFD_RELOC_GPREL32
1783 ENUMDOC
1784   For systems that allocate a Global Pointer register, these are
1785 displacements off that register.  These relocation types are
1786 handled specially, because the value the register will have is
1787 decided relatively late.
1788
1789
1790 ENUM
1791   BFD_RELOC_I960_CALLJ
1792 ENUMDOC
1793   Reloc types used for i960/b.out.
1794
1795 ENUM
1796   BFD_RELOC_NONE
1797 ENUMX
1798   BFD_RELOC_SPARC_WDISP22
1799 ENUMX
1800   BFD_RELOC_SPARC22
1801 ENUMX
1802   BFD_RELOC_SPARC13
1803 ENUMX
1804   BFD_RELOC_SPARC_GOT10
1805 ENUMX
1806   BFD_RELOC_SPARC_GOT13
1807 ENUMX
1808   BFD_RELOC_SPARC_GOT22
1809 ENUMX
1810   BFD_RELOC_SPARC_PC10
1811 ENUMX
1812   BFD_RELOC_SPARC_PC22
1813 ENUMX
1814   BFD_RELOC_SPARC_WPLT30
1815 ENUMX
1816   BFD_RELOC_SPARC_COPY
1817 ENUMX
1818   BFD_RELOC_SPARC_GLOB_DAT
1819 ENUMX
1820   BFD_RELOC_SPARC_JMP_SLOT
1821 ENUMX
1822   BFD_RELOC_SPARC_RELATIVE
1823 ENUMX
1824   BFD_RELOC_SPARC_UA32
1825 ENUMDOC
1826   SPARC ELF relocations.  There is probably some overlap with other
1827   relocation types already defined.
1828
1829 ENUM
1830   BFD_RELOC_SPARC_BASE13
1831 ENUMX
1832   BFD_RELOC_SPARC_BASE22
1833 ENUMDOC
1834   I think these are specific to SPARC a.out (e.g., Sun 4).
1835
1836 ENUMEQ
1837   BFD_RELOC_SPARC_64
1838   BFD_RELOC_64
1839 ENUMX
1840   BFD_RELOC_SPARC_10
1841 ENUMX
1842   BFD_RELOC_SPARC_11
1843 ENUMX
1844   BFD_RELOC_SPARC_OLO10
1845 ENUMX
1846   BFD_RELOC_SPARC_HH22
1847 ENUMX
1848   BFD_RELOC_SPARC_HM10
1849 ENUMX
1850   BFD_RELOC_SPARC_LM22
1851 ENUMX
1852   BFD_RELOC_SPARC_PC_HH22
1853 ENUMX
1854   BFD_RELOC_SPARC_PC_HM10
1855 ENUMX
1856   BFD_RELOC_SPARC_PC_LM22
1857 ENUMX
1858   BFD_RELOC_SPARC_WDISP16
1859 ENUMX
1860   BFD_RELOC_SPARC_WDISP19
1861 ENUMX
1862   BFD_RELOC_SPARC_7
1863 ENUMX
1864   BFD_RELOC_SPARC_6
1865 ENUMX
1866   BFD_RELOC_SPARC_5
1867 ENUMEQX
1868   BFD_RELOC_SPARC_DISP64
1869   BFD_RELOC_64_PCREL
1870 ENUMX
1871   BFD_RELOC_SPARC_PLT64
1872 ENUMX
1873   BFD_RELOC_SPARC_HIX22
1874 ENUMX
1875   BFD_RELOC_SPARC_LOX10
1876 ENUMX
1877   BFD_RELOC_SPARC_H44
1878 ENUMX
1879   BFD_RELOC_SPARC_M44
1880 ENUMX
1881   BFD_RELOC_SPARC_L44
1882 ENUMX
1883   BFD_RELOC_SPARC_REGISTER
1884 ENUMDOC
1885   SPARC64 relocations
1886
1887 ENUM
1888   BFD_RELOC_SPARC_REV32
1889 ENUMDOC
1890   SPARC little endian relocation
1891
1892 ENUM
1893   BFD_RELOC_ALPHA_GPDISP_HI16
1894 ENUMDOC
1895   Alpha ECOFF and ELF relocations.  Some of these treat the symbol or
1896      "addend" in some special way.
1897   For GPDISP_HI16 ("gpdisp") relocations, the symbol is ignored when
1898      writing; when reading, it will be the absolute section symbol.  The
1899      addend is the displacement in bytes of the "lda" instruction from
1900      the "ldah" instruction (which is at the address of this reloc).
1901 ENUM
1902   BFD_RELOC_ALPHA_GPDISP_LO16
1903 ENUMDOC
1904   For GPDISP_LO16 ("ignore") relocations, the symbol is handled as
1905      with GPDISP_HI16 relocs.  The addend is ignored when writing the
1906      relocations out, and is filled in with the file's GP value on
1907      reading, for convenience.
1908
1909 ENUM
1910   BFD_RELOC_ALPHA_GPDISP
1911 ENUMDOC
1912   The ELF GPDISP relocation is exactly the same as the GPDISP_HI16
1913      relocation except that there is no accompanying GPDISP_LO16
1914      relocation.
1915
1916 ENUM
1917   BFD_RELOC_ALPHA_LITERAL
1918 ENUMX
1919   BFD_RELOC_ALPHA_ELF_LITERAL
1920 ENUMX
1921   BFD_RELOC_ALPHA_LITUSE
1922 ENUMDOC
1923   The Alpha LITERAL/LITUSE relocs are produced by a symbol reference;
1924      the assembler turns it into a LDQ instruction to load the address of
1925      the symbol, and then fills in a register in the real instruction.
1926
1927      The LITERAL reloc, at the LDQ instruction, refers to the .lita
1928      section symbol.  The addend is ignored when writing, but is filled
1929      in with the file's GP value on reading, for convenience, as with the
1930      GPDISP_LO16 reloc.
1931
1932      The ELF_LITERAL reloc is somewhere between 16_GOTOFF and GPDISP_LO16.
1933      It should refer to the symbol to be referenced, as with 16_GOTOFF,
1934      but it generates output not based on the position within the .got
1935      section, but relative to the GP value chosen for the file during the
1936      final link stage.
1937
1938      The LITUSE reloc, on the instruction using the loaded address, gives
1939      information to the linker that it might be able to use to optimize
1940      away some literal section references.  The symbol is ignored (read
1941      as the absolute section symbol), and the "addend" indicates the type
1942      of instruction using the register:
1943               1 - "memory" fmt insn
1944               2 - byte-manipulation (byte offset reg)
1945               3 - jsr (target of branch)
1946
1947      The GNU linker currently doesn't do any of this optimizing.
1948
1949 ENUM
1950   BFD_RELOC_ALPHA_USER_LITERAL
1951 ENUMX
1952   BFD_RELOC_ALPHA_USER_LITUSE_BASE
1953 ENUMX
1954   BFD_RELOC_ALPHA_USER_LITUSE_BYTOFF
1955 ENUMX
1956   BFD_RELOC_ALPHA_USER_LITUSE_JSR
1957 ENUMX
1958   BFD_RELOC_ALPHA_USER_GPDISP
1959 ENUMX
1960   BFD_RELOC_ALPHA_USER_GPRELHIGH
1961 ENUMX
1962   BFD_RELOC_ALPHA_USER_GPRELLOW
1963 ENUMDOC
1964   The BFD_RELOC_ALPHA_USER_* relocations are used by the assembler to
1965      process the explicit !<reloc>!sequence relocations, and are mapped
1966      into the normal relocations at the end of processing.
1967
1968 ENUM
1969   BFD_RELOC_ALPHA_HINT
1970 ENUMDOC
1971   The HINT relocation indicates a value that should be filled into the
1972      "hint" field of a jmp/jsr/ret instruction, for possible branch-
1973      prediction logic which may be provided on some processors.
1974
1975 ENUM
1976   BFD_RELOC_ALPHA_LINKAGE
1977 ENUMDOC
1978   The LINKAGE relocation outputs a linkage pair in the object file,
1979      which is filled by the linker.
1980
1981 ENUM
1982   BFD_RELOC_ALPHA_CODEADDR
1983 ENUMDOC
1984   The CODEADDR relocation outputs a STO_CA in the object file,
1985      which is filled by the linker.
1986
1987 ENUM
1988   BFD_RELOC_MIPS_JMP
1989 ENUMDOC
1990   Bits 27..2 of the relocation address shifted right 2 bits;
1991      simple reloc otherwise.
1992
1993 ENUM
1994   BFD_RELOC_MIPS16_JMP
1995 ENUMDOC
1996   The MIPS16 jump instruction.
1997
1998 ENUM
1999   BFD_RELOC_MIPS16_GPREL
2000 ENUMDOC
2001   MIPS16 GP relative reloc.
2002
2003 ENUM
2004   BFD_RELOC_HI16
2005 ENUMDOC
2006   High 16 bits of 32-bit value; simple reloc.
2007 ENUM
2008   BFD_RELOC_HI16_S
2009 ENUMDOC
2010   High 16 bits of 32-bit value but the low 16 bits will be sign
2011      extended and added to form the final result.  If the low 16
2012      bits form a negative number, we need to add one to the high value
2013      to compensate for the borrow when the low bits are added.
2014 ENUM
2015   BFD_RELOC_LO16
2016 ENUMDOC
2017   Low 16 bits.
2018 ENUM
2019   BFD_RELOC_PCREL_HI16_S
2020 ENUMDOC
2021   Like BFD_RELOC_HI16_S, but PC relative.
2022 ENUM
2023   BFD_RELOC_PCREL_LO16
2024 ENUMDOC
2025   Like BFD_RELOC_LO16, but PC relative.
2026
2027 ENUMEQ
2028   BFD_RELOC_MIPS_GPREL
2029   BFD_RELOC_GPREL16
2030 ENUMDOC
2031   Relocation relative to the global pointer.
2032
2033 ENUM
2034   BFD_RELOC_MIPS_LITERAL
2035 ENUMDOC
2036   Relocation against a MIPS literal section.
2037
2038 ENUM
2039   BFD_RELOC_MIPS_GOT16
2040 ENUMX
2041   BFD_RELOC_MIPS_CALL16
2042 ENUMEQX
2043   BFD_RELOC_MIPS_GPREL32
2044   BFD_RELOC_GPREL32
2045 ENUMX
2046   BFD_RELOC_MIPS_GOT_HI16
2047 ENUMX
2048   BFD_RELOC_MIPS_GOT_LO16
2049 ENUMX
2050   BFD_RELOC_MIPS_CALL_HI16
2051 ENUMX
2052   BFD_RELOC_MIPS_CALL_LO16
2053 ENUMX
2054   BFD_RELOC_MIPS_SUB
2055 ENUMX
2056   BFD_RELOC_MIPS_GOT_PAGE
2057 ENUMX
2058   BFD_RELOC_MIPS_GOT_OFST
2059 ENUMX
2060   BFD_RELOC_MIPS_GOT_DISP
2061 COMMENT
2062 ENUMDOC
2063   MIPS ELF relocations.
2064
2065 COMMENT
2066
2067 ENUM
2068   BFD_RELOC_386_GOT32
2069 ENUMX
2070   BFD_RELOC_386_PLT32
2071 ENUMX
2072   BFD_RELOC_386_COPY
2073 ENUMX
2074   BFD_RELOC_386_GLOB_DAT
2075 ENUMX
2076   BFD_RELOC_386_JUMP_SLOT
2077 ENUMX
2078   BFD_RELOC_386_RELATIVE
2079 ENUMX
2080   BFD_RELOC_386_GOTOFF
2081 ENUMX
2082   BFD_RELOC_386_GOTPC
2083 ENUMDOC
2084   i386/elf relocations
2085
2086 ENUM
2087   BFD_RELOC_NS32K_IMM_8
2088 ENUMX
2089   BFD_RELOC_NS32K_IMM_16
2090 ENUMX
2091   BFD_RELOC_NS32K_IMM_32
2092 ENUMX
2093   BFD_RELOC_NS32K_IMM_8_PCREL
2094 ENUMX
2095   BFD_RELOC_NS32K_IMM_16_PCREL
2096 ENUMX
2097   BFD_RELOC_NS32K_IMM_32_PCREL
2098 ENUMX
2099   BFD_RELOC_NS32K_DISP_8
2100 ENUMX
2101   BFD_RELOC_NS32K_DISP_16
2102 ENUMX
2103   BFD_RELOC_NS32K_DISP_32
2104 ENUMX
2105   BFD_RELOC_NS32K_DISP_8_PCREL
2106 ENUMX
2107   BFD_RELOC_NS32K_DISP_16_PCREL
2108 ENUMX
2109   BFD_RELOC_NS32K_DISP_32_PCREL
2110 ENUMDOC
2111   ns32k relocations
2112
2113 ENUM
2114   BFD_RELOC_PJ_CODE_HI16
2115 ENUMX
2116   BFD_RELOC_PJ_CODE_LO16
2117 ENUMX
2118   BFD_RELOC_PJ_CODE_DIR16
2119 ENUMX
2120   BFD_RELOC_PJ_CODE_DIR32
2121 ENUMX
2122   BFD_RELOC_PJ_CODE_REL16
2123 ENUMX
2124   BFD_RELOC_PJ_CODE_REL32
2125 ENUMDOC
2126   Picojava relocs.  Not all of these appear in object files.
2127
2128 ENUM
2129   BFD_RELOC_PPC_B26
2130 ENUMX
2131   BFD_RELOC_PPC_BA26
2132 ENUMX
2133   BFD_RELOC_PPC_TOC16
2134 ENUMX
2135   BFD_RELOC_PPC_B16
2136 ENUMX
2137   BFD_RELOC_PPC_B16_BRTAKEN
2138 ENUMX
2139   BFD_RELOC_PPC_B16_BRNTAKEN
2140 ENUMX
2141   BFD_RELOC_PPC_BA16
2142 ENUMX
2143   BFD_RELOC_PPC_BA16_BRTAKEN
2144 ENUMX
2145   BFD_RELOC_PPC_BA16_BRNTAKEN
2146 ENUMX
2147   BFD_RELOC_PPC_COPY
2148 ENUMX
2149   BFD_RELOC_PPC_GLOB_DAT
2150 ENUMX
2151   BFD_RELOC_PPC_JMP_SLOT
2152 ENUMX
2153   BFD_RELOC_PPC_RELATIVE
2154 ENUMX
2155   BFD_RELOC_PPC_LOCAL24PC
2156 ENUMX
2157   BFD_RELOC_PPC_EMB_NADDR32
2158 ENUMX
2159   BFD_RELOC_PPC_EMB_NADDR16
2160 ENUMX
2161   BFD_RELOC_PPC_EMB_NADDR16_LO
2162 ENUMX
2163   BFD_RELOC_PPC_EMB_NADDR16_HI
2164 ENUMX
2165   BFD_RELOC_PPC_EMB_NADDR16_HA
2166 ENUMX
2167   BFD_RELOC_PPC_EMB_SDAI16
2168 ENUMX
2169   BFD_RELOC_PPC_EMB_SDA2I16
2170 ENUMX
2171   BFD_RELOC_PPC_EMB_SDA2REL
2172 ENUMX
2173   BFD_RELOC_PPC_EMB_SDA21
2174 ENUMX
2175   BFD_RELOC_PPC_EMB_MRKREF
2176 ENUMX
2177   BFD_RELOC_PPC_EMB_RELSEC16
2178 ENUMX
2179   BFD_RELOC_PPC_EMB_RELST_LO
2180 ENUMX
2181   BFD_RELOC_PPC_EMB_RELST_HI
2182 ENUMX
2183   BFD_RELOC_PPC_EMB_RELST_HA
2184 ENUMX
2185   BFD_RELOC_PPC_EMB_BIT_FLD
2186 ENUMX
2187   BFD_RELOC_PPC_EMB_RELSDA
2188 ENUMDOC
2189   Power(rs6000) and PowerPC relocations.
2190
2191 ENUM
2192   BFD_RELOC_I370_D12
2193 ENUMDOC
2194   IBM 370/390 relocations
2195
2196 ENUM
2197   BFD_RELOC_CTOR
2198 ENUMDOC
2199   The type of reloc used to build a contructor table - at the moment
2200   probably a 32 bit wide absolute relocation, but the target can choose.
2201   It generally does map to one of the other relocation types.
2202
2203 ENUM
2204   BFD_RELOC_ARM_PCREL_BRANCH
2205 ENUMDOC
2206   ARM 26 bit pc-relative branch.  The lowest two bits must be zero and are
2207   not stored in the instruction.
2208 ENUM
2209   BFD_RELOC_ARM_PCREL_BLX
2210 ENUMDOC
2211   ARM 26 bit pc-relative branch.  The lowest bit must be zero and is
2212   not stored in the instruction.  The 2nd lowest bit comes from a 1 bit
2213   field in the instruction.
2214 ENUM
2215   BFD_RELOC_THUMB_PCREL_BLX
2216 ENUMDOC
2217   Thumb 22 bit pc-relative branch.  The lowest bit must be zero and is
2218   not stored in the instruction.  The 2nd lowest bit comes from a 1 bit
2219   field in the instruction.
2220 ENUM
2221   BFD_RELOC_ARM_IMMEDIATE
2222 ENUMX
2223   BFD_RELOC_ARM_ADRL_IMMEDIATE
2224 ENUMX
2225   BFD_RELOC_ARM_OFFSET_IMM
2226 ENUMX
2227   BFD_RELOC_ARM_SHIFT_IMM
2228 ENUMX
2229   BFD_RELOC_ARM_SWI
2230 ENUMX
2231   BFD_RELOC_ARM_MULTI
2232 ENUMX
2233   BFD_RELOC_ARM_CP_OFF_IMM
2234 ENUMX
2235   BFD_RELOC_ARM_ADR_IMM
2236 ENUMX
2237   BFD_RELOC_ARM_LDR_IMM
2238 ENUMX
2239   BFD_RELOC_ARM_LITERAL
2240 ENUMX
2241   BFD_RELOC_ARM_IN_POOL
2242 ENUMX
2243   BFD_RELOC_ARM_OFFSET_IMM8
2244 ENUMX
2245   BFD_RELOC_ARM_HWLITERAL
2246 ENUMX
2247   BFD_RELOC_ARM_THUMB_ADD
2248 ENUMX
2249   BFD_RELOC_ARM_THUMB_IMM
2250 ENUMX
2251   BFD_RELOC_ARM_THUMB_SHIFT
2252 ENUMX
2253   BFD_RELOC_ARM_THUMB_OFFSET
2254 ENUMX
2255   BFD_RELOC_ARM_GOT12
2256 ENUMX
2257   BFD_RELOC_ARM_GOT32
2258 ENUMX
2259   BFD_RELOC_ARM_JUMP_SLOT
2260 ENUMX
2261   BFD_RELOC_ARM_COPY
2262 ENUMX
2263   BFD_RELOC_ARM_GLOB_DAT
2264 ENUMX
2265   BFD_RELOC_ARM_PLT32
2266 ENUMX
2267   BFD_RELOC_ARM_RELATIVE
2268 ENUMX
2269   BFD_RELOC_ARM_GOTOFF
2270 ENUMX
2271   BFD_RELOC_ARM_GOTPC
2272 ENUMDOC
2273   These relocs are only used within the ARM assembler.  They are not
2274   (at present) written to any object files.
2275
2276 ENUM
2277   BFD_RELOC_SH_PCDISP8BY2
2278 ENUMX
2279   BFD_RELOC_SH_PCDISP12BY2
2280 ENUMX
2281   BFD_RELOC_SH_IMM4
2282 ENUMX
2283   BFD_RELOC_SH_IMM4BY2
2284 ENUMX
2285   BFD_RELOC_SH_IMM4BY4
2286 ENUMX
2287   BFD_RELOC_SH_IMM8
2288 ENUMX
2289   BFD_RELOC_SH_IMM8BY2
2290 ENUMX
2291   BFD_RELOC_SH_IMM8BY4
2292 ENUMX
2293   BFD_RELOC_SH_PCRELIMM8BY2
2294 ENUMX
2295   BFD_RELOC_SH_PCRELIMM8BY4
2296 ENUMX
2297   BFD_RELOC_SH_SWITCH16
2298 ENUMX
2299   BFD_RELOC_SH_SWITCH32
2300 ENUMX
2301   BFD_RELOC_SH_USES
2302 ENUMX
2303   BFD_RELOC_SH_COUNT
2304 ENUMX
2305   BFD_RELOC_SH_ALIGN
2306 ENUMX
2307   BFD_RELOC_SH_CODE
2308 ENUMX
2309   BFD_RELOC_SH_DATA
2310 ENUMX
2311   BFD_RELOC_SH_LABEL
2312 ENUMX
2313   BFD_RELOC_SH_LOOP_START
2314 ENUMX
2315   BFD_RELOC_SH_LOOP_END
2316 ENUMDOC
2317   Hitachi SH relocs.  Not all of these appear in object files.
2318
2319 ENUM
2320   BFD_RELOC_THUMB_PCREL_BRANCH9
2321 ENUMX
2322   BFD_RELOC_THUMB_PCREL_BRANCH12
2323 ENUMX
2324   BFD_RELOC_THUMB_PCREL_BRANCH23
2325 ENUMDOC
2326   Thumb 23-, 12- and 9-bit pc-relative branches.  The lowest bit must
2327   be zero and is not stored in the instruction.
2328
2329 ENUM
2330   BFD_RELOC_ARC_B22_PCREL
2331 ENUMDOC
2332   Argonaut RISC Core (ARC) relocs.
2333   ARC 22 bit pc-relative branch.  The lowest two bits must be zero and are
2334   not stored in the instruction.  The high 20 bits are installed in bits 26
2335   through 7 of the instruction.
2336 ENUM
2337   BFD_RELOC_ARC_B26
2338 ENUMDOC
2339   ARC 26 bit absolute branch.  The lowest two bits must be zero and are not
2340   stored in the instruction.  The high 24 bits are installed in bits 23
2341   through 0.
2342
2343 ENUM
2344   BFD_RELOC_D10V_10_PCREL_R
2345 ENUMDOC
2346   Mitsubishi D10V relocs.
2347   This is a 10-bit reloc with the right 2 bits
2348   assumed to be 0.
2349 ENUM
2350   BFD_RELOC_D10V_10_PCREL_L
2351 ENUMDOC
2352   Mitsubishi D10V relocs.
2353   This is a 10-bit reloc with the right 2 bits
2354   assumed to be 0.  This is the same as the previous reloc
2355   except it is in the left container, i.e.,
2356   shifted left 15 bits.
2357 ENUM
2358   BFD_RELOC_D10V_18
2359 ENUMDOC
2360   This is an 18-bit reloc with the right 2 bits
2361   assumed to be 0.
2362 ENUM
2363   BFD_RELOC_D10V_18_PCREL
2364 ENUMDOC
2365   This is an 18-bit reloc with the right 2 bits
2366   assumed to be 0.
2367
2368 ENUM
2369   BFD_RELOC_D30V_6
2370 ENUMDOC
2371   Mitsubishi D30V relocs.
2372   This is a 6-bit absolute reloc.
2373 ENUM
2374   BFD_RELOC_D30V_9_PCREL
2375 ENUMDOC
2376   This is a 6-bit pc-relative reloc with
2377   the right 3 bits assumed to be 0.
2378 ENUM
2379   BFD_RELOC_D30V_9_PCREL_R
2380 ENUMDOC
2381   This is a 6-bit pc-relative reloc with
2382   the right 3 bits assumed to be 0. Same
2383   as the previous reloc but on the right side
2384   of the container.
2385 ENUM
2386   BFD_RELOC_D30V_15
2387 ENUMDOC
2388   This is a 12-bit absolute reloc with the
2389   right 3 bitsassumed to be 0.
2390 ENUM
2391   BFD_RELOC_D30V_15_PCREL
2392 ENUMDOC
2393   This is a 12-bit pc-relative reloc with
2394   the right 3 bits assumed to be 0.
2395 ENUM
2396   BFD_RELOC_D30V_15_PCREL_R
2397 ENUMDOC
2398   This is a 12-bit pc-relative reloc with
2399   the right 3 bits assumed to be 0. Same
2400   as the previous reloc but on the right side
2401   of the container.
2402 ENUM
2403   BFD_RELOC_D30V_21
2404 ENUMDOC
2405   This is an 18-bit absolute reloc with
2406   the right 3 bits assumed to be 0.
2407 ENUM
2408   BFD_RELOC_D30V_21_PCREL
2409 ENUMDOC
2410   This is an 18-bit pc-relative reloc with
2411   the right 3 bits assumed to be 0.
2412 ENUM
2413   BFD_RELOC_D30V_21_PCREL_R
2414 ENUMDOC
2415   This is an 18-bit pc-relative reloc with
2416   the right 3 bits assumed to be 0. Same
2417   as the previous reloc but on the right side
2418   of the container.
2419 ENUM
2420   BFD_RELOC_D30V_32
2421 ENUMDOC
2422   This is a 32-bit absolute reloc.
2423 ENUM
2424   BFD_RELOC_D30V_32_PCREL
2425 ENUMDOC
2426   This is a 32-bit pc-relative reloc.
2427
2428 ENUM
2429   BFD_RELOC_M32R_24
2430 ENUMDOC
2431   Mitsubishi M32R relocs.
2432   This is a 24 bit absolute address.
2433 ENUM
2434   BFD_RELOC_M32R_10_PCREL
2435 ENUMDOC
2436   This is a 10-bit pc-relative reloc with the right 2 bits assumed to be 0.
2437 ENUM
2438   BFD_RELOC_M32R_18_PCREL
2439 ENUMDOC
2440   This is an 18-bit reloc with the right 2 bits assumed to be 0.
2441 ENUM
2442   BFD_RELOC_M32R_26_PCREL
2443 ENUMDOC
2444   This is a 26-bit reloc with the right 2 bits assumed to be 0.
2445 ENUM
2446   BFD_RELOC_M32R_HI16_ULO
2447 ENUMDOC
2448   This is a 16-bit reloc containing the high 16 bits of an address
2449   used when the lower 16 bits are treated as unsigned.
2450 ENUM
2451   BFD_RELOC_M32R_HI16_SLO
2452 ENUMDOC
2453   This is a 16-bit reloc containing the high 16 bits of an address
2454   used when the lower 16 bits are treated as signed.
2455 ENUM
2456   BFD_RELOC_M32R_LO16
2457 ENUMDOC
2458   This is a 16-bit reloc containing the lower 16 bits of an address.
2459 ENUM
2460   BFD_RELOC_M32R_SDA16
2461 ENUMDOC
2462   This is a 16-bit reloc containing the small data area offset for use in
2463   add3, load, and store instructions.
2464
2465 ENUM
2466   BFD_RELOC_V850_9_PCREL
2467 ENUMDOC
2468   This is a 9-bit reloc
2469 ENUM
2470   BFD_RELOC_V850_22_PCREL
2471 ENUMDOC
2472   This is a 22-bit reloc
2473
2474 ENUM
2475   BFD_RELOC_V850_SDA_16_16_OFFSET
2476 ENUMDOC
2477   This is a 16 bit offset from the short data area pointer.
2478 ENUM
2479   BFD_RELOC_V850_SDA_15_16_OFFSET
2480 ENUMDOC
2481   This is a 16 bit offset (of which only 15 bits are used) from the
2482   short data area pointer.
2483 ENUM
2484   BFD_RELOC_V850_ZDA_16_16_OFFSET
2485 ENUMDOC
2486   This is a 16 bit offset from the zero data area pointer.
2487 ENUM
2488   BFD_RELOC_V850_ZDA_15_16_OFFSET
2489 ENUMDOC
2490   This is a 16 bit offset (of which only 15 bits are used) from the
2491   zero data area pointer.
2492 ENUM
2493   BFD_RELOC_V850_TDA_6_8_OFFSET
2494 ENUMDOC
2495   This is an 8 bit offset (of which only 6 bits are used) from the
2496   tiny data area pointer.
2497 ENUM
2498   BFD_RELOC_V850_TDA_7_8_OFFSET
2499 ENUMDOC
2500   This is an 8bit offset (of which only 7 bits are used) from the tiny
2501   data area pointer.
2502 ENUM
2503   BFD_RELOC_V850_TDA_7_7_OFFSET
2504 ENUMDOC
2505   This is a 7 bit offset from the tiny data area pointer.
2506 ENUM
2507   BFD_RELOC_V850_TDA_16_16_OFFSET
2508 ENUMDOC
2509   This is a 16 bit offset from the tiny data area pointer.
2510 COMMENT
2511 ENUM
2512   BFD_RELOC_V850_TDA_4_5_OFFSET
2513 ENUMDOC
2514   This is a 5 bit offset (of which only 4 bits are used) from the tiny
2515   data area pointer.
2516 ENUM
2517   BFD_RELOC_V850_TDA_4_4_OFFSET
2518 ENUMDOC
2519   This is a 4 bit offset from the tiny data area pointer.
2520 ENUM
2521   BFD_RELOC_V850_SDA_16_16_SPLIT_OFFSET
2522 ENUMDOC
2523   This is a 16 bit offset from the short data area pointer, with the
2524   bits placed non-contigously in the instruction.
2525 ENUM
2526   BFD_RELOC_V850_ZDA_16_16_SPLIT_OFFSET
2527 ENUMDOC
2528   This is a 16 bit offset from the zero data area pointer, with the
2529   bits placed non-contigously in the instruction.
2530 ENUM
2531   BFD_RELOC_V850_CALLT_6_7_OFFSET
2532 ENUMDOC
2533   This is a 6 bit offset from the call table base pointer.
2534 ENUM
2535   BFD_RELOC_V850_CALLT_16_16_OFFSET
2536 ENUMDOC
2537   This is a 16 bit offset from the call table base pointer.
2538 COMMENT
2539
2540 ENUM
2541   BFD_RELOC_MN10300_32_PCREL
2542 ENUMDOC
2543   This is a 32bit pcrel reloc for the mn10300, offset by two bytes in the
2544   instruction.
2545 ENUM
2546   BFD_RELOC_MN10300_16_PCREL
2547 ENUMDOC
2548   This is a 16bit pcrel reloc for the mn10300, offset by two bytes in the
2549   instruction.
2550
2551 ENUM
2552   BFD_RELOC_TIC30_LDP
2553 ENUMDOC
2554   This is a 8bit DP reloc for the tms320c30, where the most
2555   significant 8 bits of a 24 bit word are placed into the least
2556   significant 8 bits of the opcode.
2557
2558 ENUM
2559   BFD_RELOC_TIC54X_PARTLS7
2560 ENUMDOC
2561   This is a 7bit reloc for the tms320c54x, where the least
2562   significant 7 bits of a 16 bit word are placed into the least
2563   significant 7 bits of the opcode.
2564
2565 ENUM
2566   BFD_RELOC_TIC54X_PARTMS9
2567 ENUMDOC
2568   This is a 9bit DP reloc for the tms320c54x, where the most
2569   significant 9 bits of a 16 bit word are placed into the least
2570   significant 9 bits of the opcode.
2571
2572 ENUM
2573   BFD_RELOC_TIC54X_23
2574 ENUMDOC
2575   This is an extended address 23-bit reloc for the tms320c54x.
2576
2577 ENUM
2578   BFD_RELOC_TIC54X_16_OF_23
2579 ENUMDOC
2580   This is a 16-bit reloc for the tms320c54x, where the least
2581   significant 16 bits of a 23-bit extended address are placed into
2582   the opcode.
2583
2584 ENUM
2585   BFD_RELOC_TIC54X_MS7_OF_23
2586 ENUMDOC
2587   This is a reloc for the tms320c54x, where the most
2588   significant 7 bits of a 23-bit extended address are placed into
2589   the opcode.
2590
2591 ENUM
2592   BFD_RELOC_FR30_48
2593 ENUMDOC
2594   This is a 48 bit reloc for the FR30 that stores 32 bits.
2595 ENUM
2596   BFD_RELOC_FR30_20
2597 ENUMDOC
2598   This is a 32 bit reloc for the FR30 that stores 20 bits split up into
2599   two sections.
2600 ENUM
2601   BFD_RELOC_FR30_6_IN_4
2602 ENUMDOC
2603   This is a 16 bit reloc for the FR30 that stores a 6 bit word offset in
2604   4 bits.
2605 ENUM
2606   BFD_RELOC_FR30_8_IN_8
2607 ENUMDOC
2608   This is a 16 bit reloc for the FR30 that stores an 8 bit byte offset
2609   into 8 bits.
2610 ENUM
2611   BFD_RELOC_FR30_9_IN_8
2612 ENUMDOC
2613   This is a 16 bit reloc for the FR30 that stores a 9 bit short offset
2614   into 8 bits.
2615 ENUM
2616   BFD_RELOC_FR30_10_IN_8
2617 ENUMDOC
2618   This is a 16 bit reloc for the FR30 that stores a 10 bit word offset
2619   into 8 bits.
2620 ENUM
2621   BFD_RELOC_FR30_9_PCREL
2622 ENUMDOC
2623   This is a 16 bit reloc for the FR30 that stores a 9 bit pc relative
2624   short offset into 8 bits.
2625 ENUM
2626   BFD_RELOC_FR30_12_PCREL
2627 ENUMDOC
2628   This is a 16 bit reloc for the FR30 that stores a 12 bit pc relative
2629   short offset into 11 bits.
2630
2631 ENUM
2632   BFD_RELOC_MCORE_PCREL_IMM8BY4
2633 ENUMX
2634   BFD_RELOC_MCORE_PCREL_IMM11BY2
2635 ENUMX
2636   BFD_RELOC_MCORE_PCREL_IMM4BY2
2637 ENUMX
2638   BFD_RELOC_MCORE_PCREL_32
2639 ENUMX
2640   BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2
2641 ENUMX
2642   BFD_RELOC_MCORE_RVA
2643 ENUMDOC
2644   Motorola Mcore relocations.
2645
2646 ENUM
2647   BFD_RELOC_AVR_7_PCREL
2648 ENUMDOC
2649   This is a 16 bit reloc for the AVR that stores 8 bit pc relative
2650   short offset into 7 bits.
2651 ENUM
2652   BFD_RELOC_AVR_13_PCREL
2653 ENUMDOC
2654   This is a 16 bit reloc for the AVR that stores 13 bit pc relative
2655   short offset into 12 bits.
2656 ENUM
2657   BFD_RELOC_AVR_16_PM
2658 ENUMDOC
2659   This is a 16 bit reloc for the AVR that stores 17 bit value (usually
2660   program memory address) into 16 bits.
2661 ENUM
2662   BFD_RELOC_AVR_LO8_LDI
2663 ENUMDOC
2664   This is a 16 bit reloc for the AVR that stores 8 bit value (usually
2665   data memory address) into 8 bit immediate value of LDI insn.
2666 ENUM
2667   BFD_RELOC_AVR_HI8_LDI
2668 ENUMDOC
2669   This is a 16 bit reloc for the AVR that stores 8 bit value (high 8 bit
2670   of data memory address) into 8 bit immediate value of LDI insn.
2671 ENUM
2672   BFD_RELOC_AVR_HH8_LDI
2673 ENUMDOC
2674   This is a 16 bit reloc for the AVR that stores 8 bit value (most high 8 bit
2675   of program memory address) into 8 bit immediate value of LDI insn.
2676 ENUM
2677   BFD_RELOC_AVR_LO8_LDI_NEG
2678 ENUMDOC
2679   This is a 16 bit reloc for the AVR that stores negated 8 bit value
2680   (usually data memory address) into 8 bit immediate value of SUBI insn.
2681 ENUM
2682   BFD_RELOC_AVR_HI8_LDI_NEG
2683 ENUMDOC
2684   This is a 16 bit reloc for the AVR that stores negated 8 bit value
2685   (high 8 bit of data memory address) into 8 bit immediate value of
2686   SUBI insn.
2687 ENUM
2688   BFD_RELOC_AVR_HH8_LDI_NEG
2689 ENUMDOC
2690   This is a 16 bit reloc for the AVR that stores negated 8 bit value
2691   (most high 8 bit of program memory address) into 8 bit immediate value
2692   of LDI or SUBI insn.
2693 ENUM
2694   BFD_RELOC_AVR_LO8_LDI_PM
2695 ENUMDOC
2696   This is a 16 bit reloc for the AVR that stores 8 bit value (usually
2697   command address) into 8 bit immediate value of LDI insn.
2698 ENUM
2699   BFD_RELOC_AVR_HI8_LDI_PM
2700 ENUMDOC
2701   This is a 16 bit reloc for the AVR that stores 8 bit value (high 8 bit
2702   of command address) into 8 bit immediate value of LDI insn.
2703 ENUM
2704   BFD_RELOC_AVR_HH8_LDI_PM
2705 ENUMDOC
2706   This is a 16 bit reloc for the AVR that stores 8 bit value (most high 8 bit
2707   of command address) into 8 bit immediate value of LDI insn.
2708 ENUM
2709   BFD_RELOC_AVR_LO8_LDI_PM_NEG
2710 ENUMDOC
2711   This is a 16 bit reloc for the AVR that stores negated 8 bit value
2712   (usually command address) into 8 bit immediate value of SUBI insn.
2713 ENUM
2714   BFD_RELOC_AVR_HI8_LDI_PM_NEG
2715 ENUMDOC
2716   This is a 16 bit reloc for the AVR that stores negated 8 bit value
2717   (high 8 bit of 16 bit command address) into 8 bit immediate value
2718   of SUBI insn.
2719 ENUM
2720   BFD_RELOC_AVR_HH8_LDI_PM_NEG
2721 ENUMDOC
2722   This is a 16 bit reloc for the AVR that stores negated 8 bit value
2723   (high 6 bit of 22 bit command address) into 8 bit immediate
2724   value of SUBI insn.
2725 ENUM
2726   BFD_RELOC_AVR_CALL
2727 ENUMDOC
2728   This is a 32 bit reloc for the AVR that stores 23 bit value
2729   into 22 bits.
2730
2731 ENUM
2732   BFD_RELOC_VTABLE_INHERIT
2733 ENUMX
2734   BFD_RELOC_VTABLE_ENTRY
2735 ENUMDOC
2736   These two relocations are used by the linker to determine which of
2737   the entries in a C++ virtual function table are actually used.  When
2738   the --gc-sections option is given, the linker will zero out the entries
2739   that are not used, so that the code for those functions need not be
2740   included in the output.
2741
2742   VTABLE_INHERIT is a zero-space relocation used to describe to the
2743   linker the inheritence tree of a C++ virtual function table.  The
2744   relocation's symbol should be the parent class' vtable, and the
2745   relocation should be located at the child vtable.
2746
2747   VTABLE_ENTRY is a zero-space relocation that describes the use of a
2748   virtual function table entry.  The reloc's symbol should refer to the
2749   table of the class mentioned in the code.  Off of that base, an offset
2750   describes the entry that is being used.  For Rela hosts, this offset
2751   is stored in the reloc's addend.  For Rel hosts, we are forced to put
2752   this offset in the reloc's section offset.
2753
2754 ENUM
2755   BFD_RELOC_IA64_IMM14
2756 ENUMX
2757   BFD_RELOC_IA64_IMM22
2758 ENUMX
2759   BFD_RELOC_IA64_IMM64
2760 ENUMX
2761   BFD_RELOC_IA64_DIR32MSB
2762 ENUMX
2763   BFD_RELOC_IA64_DIR32LSB
2764 ENUMX
2765   BFD_RELOC_IA64_DIR64MSB
2766 ENUMX
2767   BFD_RELOC_IA64_DIR64LSB
2768 ENUMX
2769   BFD_RELOC_IA64_GPREL22
2770 ENUMX
2771   BFD_RELOC_IA64_GPREL64I
2772 ENUMX
2773   BFD_RELOC_IA64_GPREL32MSB
2774 ENUMX
2775   BFD_RELOC_IA64_GPREL32LSB
2776 ENUMX
2777   BFD_RELOC_IA64_GPREL64MSB
2778 ENUMX
2779   BFD_RELOC_IA64_GPREL64LSB
2780 ENUMX
2781   BFD_RELOC_IA64_LTOFF22
2782 ENUMX
2783   BFD_RELOC_IA64_LTOFF64I
2784 ENUMX
2785   BFD_RELOC_IA64_PLTOFF22
2786 ENUMX
2787   BFD_RELOC_IA64_PLTOFF64I
2788 ENUMX
2789   BFD_RELOC_IA64_PLTOFF64MSB
2790 ENUMX
2791   BFD_RELOC_IA64_PLTOFF64LSB
2792 ENUMX
2793   BFD_RELOC_IA64_FPTR64I
2794 ENUMX
2795   BFD_RELOC_IA64_FPTR32MSB
2796 ENUMX
2797   BFD_RELOC_IA64_FPTR32LSB
2798 ENUMX
2799   BFD_RELOC_IA64_FPTR64MSB
2800 ENUMX
2801   BFD_RELOC_IA64_FPTR64LSB
2802 ENUMX
2803   BFD_RELOC_IA64_PCREL21B
2804 ENUMX
2805   BFD_RELOC_IA64_PCREL21BI
2806 ENUMX
2807   BFD_RELOC_IA64_PCREL21M
2808 ENUMX
2809   BFD_RELOC_IA64_PCREL21F
2810 ENUMX
2811   BFD_RELOC_IA64_PCREL22
2812 ENUMX
2813   BFD_RELOC_IA64_PCREL60B
2814 ENUMX
2815   BFD_RELOC_IA64_PCREL64I
2816 ENUMX
2817   BFD_RELOC_IA64_PCREL32MSB
2818 ENUMX
2819   BFD_RELOC_IA64_PCREL32LSB
2820 ENUMX
2821   BFD_RELOC_IA64_PCREL64MSB
2822 ENUMX
2823   BFD_RELOC_IA64_PCREL64LSB
2824 ENUMX
2825   BFD_RELOC_IA64_LTOFF_FPTR22
2826 ENUMX
2827   BFD_RELOC_IA64_LTOFF_FPTR64I
2828 ENUMX
2829   BFD_RELOC_IA64_LTOFF_FPTR64MSB
2830 ENUMX
2831   BFD_RELOC_IA64_LTOFF_FPTR64LSB
2832 ENUMX
2833   BFD_RELOC_IA64_SEGBASE
2834 ENUMX
2835   BFD_RELOC_IA64_SEGREL32MSB
2836 ENUMX
2837   BFD_RELOC_IA64_SEGREL32LSB
2838 ENUMX
2839   BFD_RELOC_IA64_SEGREL64MSB
2840 ENUMX
2841   BFD_RELOC_IA64_SEGREL64LSB
2842 ENUMX
2843   BFD_RELOC_IA64_SECREL32MSB
2844 ENUMX
2845   BFD_RELOC_IA64_SECREL32LSB
2846 ENUMX
2847   BFD_RELOC_IA64_SECREL64MSB
2848 ENUMX
2849   BFD_RELOC_IA64_SECREL64LSB
2850 ENUMX
2851   BFD_RELOC_IA64_REL32MSB
2852 ENUMX
2853   BFD_RELOC_IA64_REL32LSB
2854 ENUMX
2855   BFD_RELOC_IA64_REL64MSB
2856 ENUMX
2857   BFD_RELOC_IA64_REL64LSB
2858 ENUMX
2859   BFD_RELOC_IA64_LTV32MSB
2860 ENUMX
2861   BFD_RELOC_IA64_LTV32LSB
2862 ENUMX
2863   BFD_RELOC_IA64_LTV64MSB
2864 ENUMX
2865   BFD_RELOC_IA64_LTV64LSB
2866 ENUMX
2867   BFD_RELOC_IA64_IPLTMSB
2868 ENUMX
2869   BFD_RELOC_IA64_IPLTLSB
2870 ENUMX
2871   BFD_RELOC_IA64_EPLTMSB
2872 ENUMX
2873   BFD_RELOC_IA64_EPLTLSB
2874 ENUMX
2875   BFD_RELOC_IA64_COPY
2876 ENUMX
2877   BFD_RELOC_IA64_TPREL22
2878 ENUMX
2879   BFD_RELOC_IA64_TPREL64MSB
2880 ENUMX
2881   BFD_RELOC_IA64_TPREL64LSB
2882 ENUMX
2883   BFD_RELOC_IA64_LTOFF_TP22
2884 ENUMX
2885   BFD_RELOC_IA64_LTOFF22X
2886 ENUMX
2887   BFD_RELOC_IA64_LDXMOV
2888 ENUMDOC
2889   Intel IA64 Relocations.
2890 ENDSENUM
2891   BFD_RELOC_UNUSED
2892 CODE_FRAGMENT
2893 .
2894 .typedef enum bfd_reloc_code_real bfd_reloc_code_real_type;
2895 */
2896
2897
2898 /*
2899 FUNCTION
2900         bfd_reloc_type_lookup
2901
2902 SYNOPSIS
2903         reloc_howto_type *
2904         bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
2905
2906 DESCRIPTION
2907         Return a pointer to a howto structure which, when
2908         invoked, will perform the relocation @var{code} on data from the
2909         architecture noted.
2910
2911 */
2912
2913
2914 reloc_howto_type *
2915 bfd_reloc_type_lookup (abfd, code)
2916      bfd *abfd;
2917      bfd_reloc_code_real_type code;
2918 {
2919   return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
2920 }
2921
2922 static reloc_howto_type bfd_howto_32 =
2923 HOWTO (0, 00, 2, 32, false, 0, complain_overflow_bitfield, 0, "VRT32", false, 0xffffffff, 0xffffffff, true);
2924
2925
2926 /*
2927 INTERNAL_FUNCTION
2928         bfd_default_reloc_type_lookup
2929
2930 SYNOPSIS
2931         reloc_howto_type *bfd_default_reloc_type_lookup
2932         (bfd *abfd, bfd_reloc_code_real_type  code);
2933
2934 DESCRIPTION
2935         Provides a default relocation lookup routine for any architecture.
2936
2937
2938 */
2939
2940 reloc_howto_type *
2941 bfd_default_reloc_type_lookup (abfd, code)
2942      bfd *abfd;
2943      bfd_reloc_code_real_type code;
2944 {
2945   switch (code)
2946     {
2947     case BFD_RELOC_CTOR:
2948       /* The type of reloc used in a ctor, which will be as wide as the
2949          address - so either a 64, 32, or 16 bitter.  */
2950       switch (bfd_get_arch_info (abfd)->bits_per_address)
2951         {
2952         case 64:
2953           BFD_FAIL ();
2954         case 32:
2955           return &bfd_howto_32;
2956         case 16:
2957           BFD_FAIL ();
2958         default:
2959           BFD_FAIL ();
2960         }
2961     default:
2962       BFD_FAIL ();
2963     }
2964   return (reloc_howto_type *) NULL;
2965 }
2966
2967 /*
2968 FUNCTION
2969         bfd_get_reloc_code_name
2970
2971 SYNOPSIS
2972         const char *bfd_get_reloc_code_name (bfd_reloc_code_real_type code);
2973
2974 DESCRIPTION
2975         Provides a printable name for the supplied relocation code.
2976         Useful mainly for printing error messages.
2977 */
2978
2979 const char *
2980 bfd_get_reloc_code_name (code)
2981      bfd_reloc_code_real_type code;
2982 {
2983   if (code > BFD_RELOC_UNUSED)
2984     return 0;
2985   return bfd_reloc_code_real_names[(int)code];
2986 }
2987
2988 /*
2989 INTERNAL_FUNCTION
2990         bfd_generic_relax_section
2991
2992 SYNOPSIS
2993         boolean bfd_generic_relax_section
2994          (bfd *abfd,
2995           asection *section,
2996           struct bfd_link_info *,
2997           boolean *);
2998
2999 DESCRIPTION
3000         Provides default handling for relaxing for back ends which
3001         don't do relaxing -- i.e., does nothing.
3002 */
3003
3004 /*ARGSUSED*/
3005 boolean
3006 bfd_generic_relax_section (abfd, section, link_info, again)
3007      bfd *abfd ATTRIBUTE_UNUSED;
3008      asection *section ATTRIBUTE_UNUSED;
3009      struct bfd_link_info *link_info ATTRIBUTE_UNUSED;
3010      boolean *again;
3011 {
3012   *again = false;
3013   return true;
3014 }
3015
3016 /*
3017 INTERNAL_FUNCTION
3018         bfd_generic_gc_sections
3019
3020 SYNOPSIS
3021         boolean bfd_generic_gc_sections
3022          (bfd *, struct bfd_link_info *);
3023
3024 DESCRIPTION
3025         Provides default handling for relaxing for back ends which
3026         don't do section gc -- i.e., does nothing.
3027 */
3028
3029 /*ARGSUSED*/
3030 boolean
3031 bfd_generic_gc_sections (abfd, link_info)
3032      bfd *abfd ATTRIBUTE_UNUSED;
3033      struct bfd_link_info *link_info ATTRIBUTE_UNUSED;
3034 {
3035   return true;
3036 }
3037
3038 /*
3039 INTERNAL_FUNCTION
3040         bfd_generic_get_relocated_section_contents
3041
3042 SYNOPSIS
3043         bfd_byte *
3044            bfd_generic_get_relocated_section_contents (bfd *abfd,
3045              struct bfd_link_info *link_info,
3046              struct bfd_link_order *link_order,
3047              bfd_byte *data,
3048              boolean relocateable,
3049              asymbol **symbols);
3050
3051 DESCRIPTION
3052         Provides default handling of relocation effort for back ends
3053         which can't be bothered to do it efficiently.
3054
3055 */
3056
3057 bfd_byte *
3058 bfd_generic_get_relocated_section_contents (abfd, link_info, link_order, data,
3059                                             relocateable, symbols)
3060      bfd *abfd;
3061      struct bfd_link_info *link_info;
3062      struct bfd_link_order *link_order;
3063      bfd_byte *data;
3064      boolean relocateable;
3065      asymbol **symbols;
3066 {
3067   /* Get enough memory to hold the stuff */
3068   bfd *input_bfd = link_order->u.indirect.section->owner;
3069   asection *input_section = link_order->u.indirect.section;
3070
3071   long reloc_size = bfd_get_reloc_upper_bound (input_bfd, input_section);
3072   arelent **reloc_vector = NULL;
3073   long reloc_count;
3074
3075   if (reloc_size < 0)
3076     goto error_return;
3077
3078   reloc_vector = (arelent **) bfd_malloc ((size_t) reloc_size);
3079   if (reloc_vector == NULL && reloc_size != 0)
3080     goto error_return;
3081
3082   /* read in the section */
3083   if (!bfd_get_section_contents (input_bfd,
3084                                  input_section,
3085                                  (PTR) data,
3086                                  0,
3087                                  input_section->_raw_size))
3088     goto error_return;
3089
3090   /* We're not relaxing the section, so just copy the size info */
3091   input_section->_cooked_size = input_section->_raw_size;
3092   input_section->reloc_done = true;
3093
3094   reloc_count = bfd_canonicalize_reloc (input_bfd,
3095                                         input_section,
3096                                         reloc_vector,
3097                                         symbols);
3098   if (reloc_count < 0)
3099     goto error_return;
3100
3101   if (reloc_count > 0)
3102     {
3103       arelent **parent;
3104       for (parent = reloc_vector; *parent != (arelent *) NULL;
3105            parent++)
3106         {
3107           char *error_message = (char *) NULL;
3108           bfd_reloc_status_type r =
3109             bfd_perform_relocation (input_bfd,
3110                                     *parent,
3111                                     (PTR) data,
3112                                     input_section,
3113                                     relocateable ? abfd : (bfd *) NULL,
3114                                     &error_message);
3115
3116           if (relocateable)
3117             {
3118               asection *os = input_section->output_section;
3119
3120               /* A partial link, so keep the relocs */
3121               os->orelocation[os->reloc_count] = *parent;
3122               os->reloc_count++;
3123             }
3124
3125           if (r != bfd_reloc_ok)
3126             {
3127               switch (r)
3128                 {
3129                 case bfd_reloc_undefined:
3130                   if (!((*link_info->callbacks->undefined_symbol)
3131                         (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
3132                          input_bfd, input_section, (*parent)->address,
3133                          true)))
3134                     goto error_return;
3135                   break;
3136                 case bfd_reloc_dangerous:
3137                   BFD_ASSERT (error_message != (char *) NULL);
3138                   if (!((*link_info->callbacks->reloc_dangerous)
3139                         (link_info, error_message, input_bfd, input_section,
3140                          (*parent)->address)))
3141                     goto error_return;
3142                   break;
3143                 case bfd_reloc_overflow:
3144                   if (!((*link_info->callbacks->reloc_overflow)
3145                         (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
3146                          (*parent)->howto->name, (*parent)->addend,
3147                          input_bfd, input_section, (*parent)->address)))
3148                     goto error_return;
3149                   break;
3150                 case bfd_reloc_outofrange:
3151                 default:
3152                   abort ();
3153                   break;
3154                 }
3155
3156             }
3157         }
3158     }
3159   if (reloc_vector != NULL)
3160     free (reloc_vector);
3161   return data;
3162
3163 error_return:
3164   if (reloc_vector != NULL)
3165     free (reloc_vector);
3166   return NULL;
3167 }