bfd/reloc.c

   1 /* BFD support for handling relocation entries.
   2    Copyright (C) 1990, 91, 92, 93, 94, 95, 96, 97, 98, 1999
   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-mass 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 .       {* When performing a partial link, some formats must modify the
 344 .          relocations rather than the data - this flag signals this.*}
 345 .  boolean partial_inplace;
 346 .
 347 .       {* The src_mask selects which parts of the read in data
 348 .          are to be used in the relocation sum.  E.g., if this was an 8 bit
 349 .          bit of data which we read and relocated, this would be
 350 .          0x000000ff. When we have relocs which have an addend, such as
 351 .          sun4 extended relocs, the value in the offset part of a
 352 .          relocating field is garbage so we never use it. In this case
 353 .          the mask would be 0x00000000. *}
 354 .  bfd_vma src_mask;
 355 .
 356 .       {* The dst_mask selects which parts of the instruction are replaced
 357 .          into the instruction. In most cases src_mask == dst_mask,
 358 .          except in the above special case, where dst_mask would be
 359 .          0x000000ff, and src_mask would be 0x00000000.   *}
 360 .  bfd_vma dst_mask;
 361 .
 362 .       {* When some formats create PC relative instructions, they leave
 363 .          the value of the pc of the place being relocated in the offset
 364 .          slot of the instruction, so that a PC relative relocation can
 365 .          be made just by adding in an ordinary offset (e.g., sun3 a.out).
 366 .          Some formats leave the displacement part of an instruction
 367 .          empty (e.g., m88k bcs); this flag signals the fact.*}
 368 .  boolean pcrel_offset;
 369 .
 370 .};
 371
 372 */
 373
 374 /*
 375 FUNCTION
 376         The HOWTO Macro
 377
 378 DESCRIPTION
 379         The HOWTO define is horrible and will go away.
 380
 381
 382 .#define HOWTO(C, R,S,B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
 383 .  {(unsigned)C,R,S,B, P, BI, O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
 384
 385 DESCRIPTION
 386         And will be replaced with the totally magic way. But for the
 387         moment, we are compatible, so do it this way.
 388
 389
 390 .#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,complain_overflow_dont,FUNCTION, NAME,false,0,0,IN)
 391 .
 392 DESCRIPTION
 393         Helper routine to turn a symbol into a relocation value.
 394
 395 .#define HOWTO_PREPARE(relocation, symbol)      \
 396 .  {                                            \
 397 .  if (symbol != (asymbol *)NULL) {             \
 398 .    if (bfd_is_com_section (symbol->section)) { \
 399 .      relocation = 0;                          \
 400 .    }                                          \
 401 .    else {                                     \
 402 .      relocation = symbol->value;              \
 403 .    }                                          \
 404 .  }                                            \
 405 .}
 406
 407 */
 408
 409 /*
 410 FUNCTION
 411         bfd_get_reloc_size
 412
 413 SYNOPSIS
 414         unsigned int bfd_get_reloc_size (reloc_howto_type *);
 415
 416 DESCRIPTION
 417         For a reloc_howto_type that operates on a fixed number of bytes,
 418         this returns the number of bytes operated on.
 419  */
 420
 421 unsigned int
 422 bfd_get_reloc_size (howto)
 423      reloc_howto_type *howto;
 424 {
 425   switch (howto->size)
 426     {
 427     case 0: return 1;
 428     case 1: return 2;
 429     case 2: return 4;
 430     case 3: return 0;
 431     case 4: return 8;
 432     case 8: return 16;
 433     case -2: return 4;
 434     default: abort ();
 435     }
 436 }
 437
 438 /*
 439 TYPEDEF
 440         arelent_chain
 441
 442 DESCRIPTION
 443
 444         How relocs are tied together in an <<asection>>:
 445
 446 .typedef struct relent_chain {
 447 .  arelent relent;
 448 .  struct   relent_chain *next;
 449 .} arelent_chain;
 450
 451 */
 452
 453 /* N_ONES produces N one bits, without overflowing machine arithmetic.  */
 454 #define N_ONES(n) (((((bfd_vma) 1 << ((n) - 1)) - 1) << 1) | 1)
 455
 456 /*
 457 FUNCTION
 458         bfd_check_overflow
 459
 460 SYNOPSIS
 461         bfd_reloc_status_type
 462                 bfd_check_overflow
 463                         (enum complain_overflow how,
 464                          unsigned int bitsize,
 465                          unsigned int rightshift,
 466                          unsigned int addrsize,
 467                          bfd_vma relocation);
 468
 469 DESCRIPTION
 470         Perform overflow checking on @var{relocation} which has
 471         @var{bitsize} significant bits and will be shifted right by
 472         @var{rightshift} bits, on a machine with addresses containing
 473         @var{addrsize} significant bits.  The result is either of
 474         @code{bfd_reloc_ok} or @code{bfd_reloc_overflow}.
 475
 476 */
 477
 478 bfd_reloc_status_type
 479 bfd_check_overflow (how, bitsize, rightshift, addrsize, relocation)
 480      enum complain_overflow how;
 481      unsigned int bitsize;
 482      unsigned int rightshift;
 483      unsigned int addrsize;
 484      bfd_vma relocation;
 485 {
 486   bfd_vma fieldmask, addrmask, signmask, ss, a;
 487   bfd_reloc_status_type flag = bfd_reloc_ok;
 488
 489   a = relocation;
 490
 491   /* Note: BITSIZE should always be <= ADDRSIZE, but in case it's not,
 492      we'll be permissive: extra bits in the field mask will
 493      automatically extend the address mask for purposes of the
 494      overflow check.  */
 495   fieldmask = N_ONES (bitsize);
 496   addrmask = N_ONES (addrsize) | fieldmask;
 497
 498   switch (how)
 499     {
 500     case complain_overflow_dont:
 501       break;
 502
 503     case complain_overflow_signed:
 504       /* If any sign bits are set, all sign bits must be set.  That
 505          is, A must be a valid negative address after shifting.  */
 506       a = (a & addrmask) >> rightshift;
 507       signmask = ~ (fieldmask >> 1);
 508       ss = a & signmask;
 509       if (ss != 0 && ss != ((addrmask >> rightshift) & signmask))
 510         flag = bfd_reloc_overflow;
 511       break;
 512
 513     case complain_overflow_unsigned:
 514       /* We have an overflow if the address does not fit in the field.  */
 515       a = (a & addrmask) >> rightshift;
 516       if ((a & ~ fieldmask) != 0)
 517         flag = bfd_reloc_overflow;
 518       break;
 519
 520     case complain_overflow_bitfield:
 521       /* Bitfields are sometimes signed, sometimes unsigned.  We
 522          overflow if the value has some, but not all, bits set outside
 523          the field, or if it has any bits set outside the field but
 524          the sign bit is not set.  */
 525       a >>= rightshift;
 526       if ((a & ~ fieldmask) != 0)
 527         {
 528           signmask = (fieldmask >> 1) + 1;
 529           ss = (signmask << rightshift) - 1;
 530           if ((ss | relocation) != ~ (bfd_vma) 0)
 531             flag = bfd_reloc_overflow;
 532         }
 533       break;
 534
 535     default:
 536       abort ();
 537     }
 538
 539   return flag;
 540 }
 541
 542 /*
 543 FUNCTION
 544         bfd_perform_relocation
 545
 546 SYNOPSIS
 547         bfd_reloc_status_type
 548                 bfd_perform_relocation
 549                         (bfd *abfd,
 550                          arelent *reloc_entry,
 551                          PTR data,
 552                          asection *input_section,
 553                          bfd *output_bfd,
 554                          char **error_message);
 555
 556 DESCRIPTION
 557         If @var{output_bfd} is supplied to this function, the
 558         generated image will be relocatable; the relocations are
 559         copied to the output file after they have been changed to
 560         reflect the new state of the world. There are two ways of
 561         reflecting the results of partial linkage in an output file:
 562         by modifying the output data in place, and by modifying the
 563         relocation record.  Some native formats (e.g., basic a.out and
 564         basic coff) have no way of specifying an addend in the
 565         relocation type, so the addend has to go in the output data.
 566         This is no big deal since in these formats the output data
 567         slot will always be big enough for the addend. Complex reloc
 568         types with addends were invented to solve just this problem.
 569         The @var{error_message} argument is set to an error message if
 570         this return @code{bfd_reloc_dangerous}.
 571
 572 */
 573
 574
 575 bfd_reloc_status_type
 576 bfd_perform_relocation (abfd, reloc_entry, data, input_section, output_bfd,
 577                         error_message)
 578      bfd *abfd;
 579      arelent *reloc_entry;
 580      PTR data;
 581      asection *input_section;
 582      bfd *output_bfd;
 583      char **error_message;
 584 {
 585   bfd_vma relocation;
 586   bfd_reloc_status_type flag = bfd_reloc_ok;
 587   bfd_size_type addr = reloc_entry->address;
 588   bfd_vma output_base = 0;
 589   reloc_howto_type *howto = reloc_entry->howto;
 590   asection *reloc_target_output_section;
 591   asymbol *symbol;
 592
 593   symbol = *(reloc_entry->sym_ptr_ptr);
 594   if (bfd_is_abs_section (symbol->section)
 595       && output_bfd != (bfd *) NULL)
 596     {
 597       reloc_entry->address += input_section->output_offset;
 598       return bfd_reloc_ok;
 599     }
 600
 601   /* If we are not producing relocateable output, return an error if
 602      the symbol is not defined.  An undefined weak symbol is
 603      considered to have a value of zero (SVR4 ABI, p. 4-27).  */
 604   if (bfd_is_und_section (symbol->section)
 605       && (symbol->flags & BSF_WEAK) == 0
 606       && output_bfd == (bfd *) NULL)
 607     flag = bfd_reloc_undefined;
 608
 609   /* If there is a function supplied to handle this relocation type,
 610      call it.  It'll return `bfd_reloc_continue' if further processing
 611      can be done.  */
 612   if (howto->special_function)
 613     {
 614       bfd_reloc_status_type cont;
 615       cont = howto->special_function (abfd, reloc_entry, symbol, data,
 616                                       input_section, output_bfd,
 617                                       error_message);
 618       if (cont != bfd_reloc_continue)
 619         return cont;
 620     }
 621
 622   /* Is the address of the relocation really within the section?  */
 623   if (reloc_entry->address > input_section->_cooked_size)
 624     return bfd_reloc_outofrange;
 625
 626   /* Work out which section the relocation is targetted at and the
 627      initial relocation command value.  */
 628
 629   /* Get symbol value.  (Common symbols are special.)  */
 630   if (bfd_is_com_section (symbol->section))
 631     relocation = 0;
 632   else
 633     relocation = symbol->value;
 634
 635
 636   reloc_target_output_section = symbol->section->output_section;
 637
 638   /* Convert input-section-relative symbol value to absolute.  */
 639   if (output_bfd && howto->partial_inplace == false)
 640     output_base = 0;
 641   else
 642     output_base = reloc_target_output_section->vma;
 643
 644   relocation += output_base + symbol->section->output_offset;
 645
 646   /* Add in supplied addend.  */
 647   relocation += reloc_entry->addend;
 648
 649   /* Here the variable relocation holds the final address of the
 650      symbol we are relocating against, plus any addend.  */
 651
 652   if (howto->pc_relative == true)
 653     {
 654       /* This is a PC relative relocation.  We want to set RELOCATION
 655          to the distance between the address of the symbol and the
 656          location.  RELOCATION is already the address of the symbol.
 657
 658          We start by subtracting the address of the section containing
 659          the location.
 660
 661          If pcrel_offset is set, we must further subtract the position
 662          of the location within the section.  Some targets arrange for
 663          the addend to be the negative of the position of the location
 664          within the section; for example, i386-aout does this.  For
 665          i386-aout, pcrel_offset is false.  Some other targets do not
 666          include the position of the location; for example, m88kbcs,
 667          or ELF.  For those targets, pcrel_offset is true.
 668
 669          If we are producing relocateable output, then we must ensure
 670          that this reloc will be correctly computed when the final
 671          relocation is done.  If pcrel_offset is false we want to wind
 672          up with the negative of the location within the section,
 673          which means we must adjust the existing addend by the change
 674          in the location within the section.  If pcrel_offset is true
 675          we do not want to adjust the existing addend at all.
 676
 677          FIXME: This seems logical to me, but for the case of
 678          producing relocateable output it is not what the code
 679          actually does.  I don't want to change it, because it seems
 680          far too likely that something will break.  */
 681
 682       relocation -=
 683         input_section->output_section->vma + input_section->output_offset;
 684
 685       if (howto->pcrel_offset == true)
 686         relocation -= reloc_entry->address;
 687     }
 688
 689   if (output_bfd != (bfd *) NULL)
 690     {
 691       if (howto->partial_inplace == false)
 692         {
 693           /* This is a partial relocation, and we want to apply the relocation
 694              to the reloc entry rather than the raw data. Modify the reloc
 695              inplace to reflect what we now know.  */
 696           reloc_entry->addend = relocation;
 697           reloc_entry->address += input_section->output_offset;
 698           return flag;
 699         }
 700       else
 701         {
 702           /* This is a partial relocation, but inplace, so modify the
 703              reloc record a bit.
 704
 705              If we've relocated with a symbol with a section, change
 706              into a ref to the section belonging to the symbol.  */
 707
 708           reloc_entry->address += input_section->output_offset;
 709
 710           /* WTF?? */
 711           if (abfd->xvec->flavour == bfd_target_coff_flavour
 712               && strcmp (abfd->xvec->name, "aixcoff-rs6000") != 0
 713               && strcmp (abfd->xvec->name, "xcoff-powermac") != 0
 714               && strcmp (abfd->xvec->name, "coff-Intel-little") != 0
 715               && strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
 716             {
 717 #if 1
 718               /* For m68k-coff, the addend was being subtracted twice during
 719                  relocation with -r.  Removing the line below this comment
 720                  fixes that problem; see PR 2953.
 721
 722 However, Ian wrote the following, regarding removing the line below,
 723 which explains why it is still enabled:  --djm
 724
 725 If you put a patch like that into BFD you need to check all the COFF
 726 linkers.  I am fairly certain that patch will break coff-i386 (e.g.,
 727 SCO); see coff_i386_reloc in coff-i386.c where I worked around the
 728 problem in a different way.  There may very well be a reason that the
 729 code works as it does.
 730
 731 Hmmm.  The first obvious point is that bfd_perform_relocation should
 732 not have any tests that depend upon the flavour.  It's seem like
 733 entirely the wrong place for such a thing.  The second obvious point
 734 is that the current code ignores the reloc addend when producing
 735 relocateable output for COFF.  That's peculiar.  In fact, I really
 736 have no idea what the point of the line you want to remove is.
 737
 738 A typical COFF reloc subtracts the old value of the symbol and adds in
 739 the new value to the location in the object file (if it's a pc
 740 relative reloc it adds the difference between the symbol value and the
 741 location).  When relocating we need to preserve that property.
 742
 743 BFD handles this by setting the addend to the negative of the old
 744 value of the symbol.  Unfortunately it handles common symbols in a
 745 non-standard way (it doesn't subtract the old value) but that's a
 746 different story (we can't change it without losing backward
 747 compatibility with old object files) (coff-i386 does subtract the old
 748 value, to be compatible with existing coff-i386 targets, like SCO).
 749
 750 So everything works fine when not producing relocateable output.  When
 751 we are producing relocateable output, logically we should do exactly
 752 what we do when not producing relocateable output.  Therefore, your
 753 patch is correct.  In fact, it should probably always just set
 754 reloc_entry->addend to 0 for all cases, since it is, in fact, going to
 755 add the value into the object file.  This won't hurt the COFF code,
 756 which doesn't use the addend; I'm not sure what it will do to other
 757 formats (the thing to check for would be whether any formats both use
 758 the addend and set partial_inplace).
 759
 760 When I wanted to make coff-i386 produce relocateable output, I ran
 761 into the problem that you are running into: I wanted to remove that
 762 line.  Rather than risk it, I made the coff-i386 relocs use a special
 763 function; it's coff_i386_reloc in coff-i386.c.  The function
 764 specifically adds the addend field into the object file, knowing that
 765 bfd_perform_relocation is not going to.  If you remove that line, then
 766 coff-i386.c will wind up adding the addend field in twice.  It's
 767 trivial to fix; it just needs to be done.
 768
 769 The problem with removing the line is just that it may break some
 770 working code.  With BFD it's hard to be sure of anything.  The right
 771 way to deal with this is simply to build and test at least all the
 772 supported COFF targets.  It should be straightforward if time and disk
 773 space consuming.  For each target:
 774     1) build the linker
 775     2) generate some executable, and link it using -r (I would
 776        probably use paranoia.o and link against newlib/libc.a, which
 777        for all the supported targets would be available in
 778        /usr/cygnus/progressive/H-host/target/lib/libc.a).
 779     3) make the change to reloc.c
 780     4) rebuild the linker
 781     5) repeat step 2
 782     6) if the resulting object files are the same, you have at least
 783        made it no worse
 784     7) if they are different you have to figure out which version is
 785        right
 786 */
 787               relocation -= reloc_entry->addend;
 788 #endif
 789               reloc_entry->addend = 0;
 790             }
 791           else
 792             {
 793               reloc_entry->addend = relocation;
 794             }
 795         }
 796     }
 797   else
 798     {
 799       reloc_entry->addend = 0;
 800     }
 801
 802   /* FIXME: This overflow checking is incomplete, because the value
 803      might have overflowed before we get here.  For a correct check we
 804      need to compute the value in a size larger than bitsize, but we
 805      can't reasonably do that for a reloc the same size as a host
 806      machine word.
 807      FIXME: We should also do overflow checking on the result after
 808      adding in the value contained in the object file.  */
 809   if (howto->complain_on_overflow != complain_overflow_dont
 810       && flag == bfd_reloc_ok)
 811     flag = bfd_check_overflow (howto->complain_on_overflow,
 812                                howto->bitsize,
 813                                howto->rightshift,
 814                                bfd_arch_bits_per_address (abfd),
 815                                relocation);
 816
 817   /*
 818     Either we are relocating all the way, or we don't want to apply
 819     the relocation to the reloc entry (probably because there isn't
 820     any room in the output format to describe addends to relocs)
 821     */
 822
 823   /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
 824      (OSF version 1.3, compiler version 3.11).  It miscompiles the
 825      following program:
 826
 827      struct str
 828      {
 829        unsigned int i0;
 830      } s = { 0 };
 831
 832      int
 833      main ()
 834      {
 835        unsigned long x;
 836
 837        x = 0x100000000;
 838        x <<= (unsigned long) s.i0;
 839        if (x == 0)
 840          printf ("failed\n");
 841        else
 842          printf ("succeeded (%lx)\n", x);
 843      }
 844      */
 845
 846   relocation >>= (bfd_vma) howto->rightshift;
 847
 848   /* Shift everything up to where it's going to be used */
 849
 850   relocation <<= (bfd_vma) howto->bitpos;
 851
 852   /* Wait for the day when all have the mask in them */
 853
 854   /* What we do:
 855      i instruction to be left alone
 856      o offset within instruction
 857      r relocation offset to apply
 858      S src mask
 859      D dst mask
 860      N ~dst mask
 861      A part 1
 862      B part 2
 863      R result
 864
 865      Do this:
 866      i i i i i o o o o o        from bfd_get<size>
 867      and           S S S S S    to get the size offset we want
 868      +   r r r r r r r r r r  to get the final value to place
 869      and           D D D D D  to chop to right size
 870      -----------------------
 871      A A A A A
 872      And this:
 873      ...   i i i i i o o o o o  from bfd_get<size>
 874      and   N N N N N            get instruction
 875      -----------------------
 876      ...   B B B B B
 877
 878      And then:
 879      B B B B B
 880      or              A A A A A
 881      -----------------------
 882      R R R R R R R R R R        put into bfd_put<size>
 883      */
 884
 885 #define DOIT(x) \
 886   x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) +  relocation) & howto->dst_mask))
 887
 888   switch (howto->size)
 889     {
 890     case 0:
 891       {
 892         char x = bfd_get_8 (abfd, (char *) data + addr);
 893         DOIT (x);
 894         bfd_put_8 (abfd, x, (unsigned char *) data + addr);
 895       }
 896       break;
 897
 898     case 1:
 899       {
 900         short x = bfd_get_16 (abfd, (bfd_byte *) data + addr);
 901         DOIT (x);
 902         bfd_put_16 (abfd, x, (unsigned char *) data + addr);
 903       }
 904       break;
 905     case 2:
 906       {
 907         long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
 908         DOIT (x);
 909         bfd_put_32 (abfd, x, (bfd_byte *) data + addr);
 910       }
 911       break;
 912     case -2:
 913       {
 914         long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
 915         relocation = -relocation;
 916         DOIT (x);
 917         bfd_put_32 (abfd, x, (bfd_byte *) data + addr);
 918       }
 919       break;
 920
 921     case -1:
 922       {
 923         long x = bfd_get_16 (abfd, (bfd_byte *) data + addr);
 924         relocation = -relocation;
 925         DOIT (x);
 926         bfd_put_16 (abfd, x, (bfd_byte *) data + addr);
 927       }
 928       break;
 929
 930     case 3:
 931       /* Do nothing */
 932       break;
 933
 934     case 4:
 935 #ifdef BFD64
 936       {
 937         bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data + addr);
 938         DOIT (x);
 939         bfd_put_64 (abfd, x, (bfd_byte *) data + addr);
 940       }
 941 #else
 942       abort ();
 943 #endif
 944       break;
 945     default:
 946       return bfd_reloc_other;
 947     }
 948
 949   return flag;
 950 }
 951
 952 /*
 953 FUNCTION
 954         bfd_install_relocation
 955
 956 SYNOPSIS
 957         bfd_reloc_status_type
 958                 bfd_install_relocation
 959                         (bfd *abfd,
 960                          arelent *reloc_entry,
 961                          PTR data, bfd_vma data_start,
 962                          asection *input_section,
 963                          char **error_message);
 964
 965 DESCRIPTION
 966         This looks remarkably like <<bfd_perform_relocation>>, except it
 967         does not expect that the section contents have been filled in.
 968         I.e., it's suitable for use when creating, rather than applying
 969         a relocation.
 970
 971         For now, this function should be considered reserved for the
 972         assembler.
 973
 974 */
 975
 976
 977 bfd_reloc_status_type
 978 bfd_install_relocation (abfd, reloc_entry, data_start, data_start_offset,
 979                         input_section, error_message)
 980      bfd *abfd;
 981      arelent *reloc_entry;
 982      PTR data_start;
 983      bfd_vma data_start_offset;
 984      asection *input_section;
 985      char **error_message;
 986 {
 987   bfd_vma relocation;
 988   bfd_reloc_status_type flag = bfd_reloc_ok;
 989   bfd_size_type addr = reloc_entry->address;
 990   bfd_vma output_base = 0;
 991   reloc_howto_type *howto = reloc_entry->howto;
 992   asection *reloc_target_output_section;
 993   asymbol *symbol;
 994   bfd_byte *data;
 995
 996   symbol = *(reloc_entry->sym_ptr_ptr);
 997   if (bfd_is_abs_section (symbol->section))
 998     {
 999       reloc_entry->address += input_section->output_offset;
1000       return bfd_reloc_ok;
1001     }
1002
1003   /* If there is a function supplied to handle this relocation type,
1004      call it.  It'll return `bfd_reloc_continue' if further processing
1005      can be done.  */
1006   if (howto->special_function)
1007     {
1008       bfd_reloc_status_type cont;
1009
1010       /* XXX - The special_function calls haven't been fixed up to deal
1011          with creating new relocations and section contents.  */
1012       cont = howto->special_function (abfd, reloc_entry, symbol,
1013                                       /* XXX - Non-portable! */
1014                                       ((bfd_byte *) data_start
1015                                        - data_start_offset),
1016                                       input_section, abfd, error_message);
1017       if (cont != bfd_reloc_continue)
1018         return cont;
1019     }
1020
1021   /* Is the address of the relocation really within the section?  */
1022   if (reloc_entry->address > input_section->_cooked_size)
1023     return bfd_reloc_outofrange;
1024
1025   /* Work out which section the relocation is targetted at and the
1026      initial relocation command value.  */
1027
1028   /* Get symbol value.  (Common symbols are special.)  */
1029   if (bfd_is_com_section (symbol->section))
1030     relocation = 0;
1031   else
1032     relocation = symbol->value;
1033
1034   reloc_target_output_section = symbol->section->output_section;
1035
1036   /* Convert input-section-relative symbol value to absolute.  */
1037   if (howto->partial_inplace == false)
1038     output_base = 0;
1039   else
1040     output_base = reloc_target_output_section->vma;
1041
1042   relocation += output_base + symbol->section->output_offset;
1043
1044   /* Add in supplied addend.  */
1045   relocation += reloc_entry->addend;
1046
1047   /* Here the variable relocation holds the final address of the
1048      symbol we are relocating against, plus any addend.  */
1049
1050   if (howto->pc_relative == true)
1051     {
1052       /* This is a PC relative relocation.  We want to set RELOCATION
1053          to the distance between the address of the symbol and the
1054          location.  RELOCATION is already the address of the symbol.
1055
1056          We start by subtracting the address of the section containing
1057          the location.
1058
1059          If pcrel_offset is set, we must further subtract the position
1060          of the location within the section.  Some targets arrange for
1061          the addend to be the negative of the position of the location
1062          within the section; for example, i386-aout does this.  For
1063          i386-aout, pcrel_offset is false.  Some other targets do not
1064          include the position of the location; for example, m88kbcs,
1065          or ELF.  For those targets, pcrel_offset is true.
1066
1067          If we are producing relocateable output, then we must ensure
1068          that this reloc will be correctly computed when the final
1069          relocation is done.  If pcrel_offset is false we want to wind
1070          up with the negative of the location within the section,
1071          which means we must adjust the existing addend by the change
1072          in the location within the section.  If pcrel_offset is true
1073          we do not want to adjust the existing addend at all.
1074
1075          FIXME: This seems logical to me, but for the case of
1076          producing relocateable output it is not what the code
1077          actually does.  I don't want to change it, because it seems
1078          far too likely that something will break.  */
1079
1080       relocation -=
1081         input_section->output_section->vma + input_section->output_offset;
1082
1083       if (howto->pcrel_offset == true && howto->partial_inplace == true)
1084         relocation -= reloc_entry->address;
1085     }
1086
1087   if (howto->partial_inplace == false)
1088     {
1089       /* This is a partial relocation, and we want to apply the relocation
1090          to the reloc entry rather than the raw data. Modify the reloc
1091          inplace to reflect what we now know.  */
1092       reloc_entry->addend = relocation;
1093       reloc_entry->address += input_section->output_offset;
1094       return flag;
1095     }
1096   else
1097     {
1098       /* This is a partial relocation, but inplace, so modify the
1099          reloc record a bit.
1100
1101          If we've relocated with a symbol with a section, change
1102          into a ref to the section belonging to the symbol.  */
1103
1104       reloc_entry->address += input_section->output_offset;
1105
1106       /* WTF?? */
1107       if (abfd->xvec->flavour == bfd_target_coff_flavour
1108           && strcmp (abfd->xvec->name, "aixcoff-rs6000") != 0
1109           && strcmp (abfd->xvec->name, "xcoff-powermac") != 0
1110           && strcmp (abfd->xvec->name, "coff-Intel-little") != 0
1111           && strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
1112         {
1113 #if 1
1114 /* For m68k-coff, the addend was being subtracted twice during
1115    relocation with -r.  Removing the line below this comment
1116    fixes that problem; see PR 2953.
1117
1118 However, Ian wrote the following, regarding removing the line below,
1119 which explains why it is still enabled:  --djm
1120
1121 If you put a patch like that into BFD you need to check all the COFF
1122 linkers.  I am fairly certain that patch will break coff-i386 (e.g.,
1123 SCO); see coff_i386_reloc in coff-i386.c where I worked around the
1124 problem in a different way.  There may very well be a reason that the
1125 code works as it does.
1126
1127 Hmmm.  The first obvious point is that bfd_install_relocation should
1128 not have any tests that depend upon the flavour.  It's seem like
1129 entirely the wrong place for such a thing.  The second obvious point
1130 is that the current code ignores the reloc addend when producing
1131 relocateable output for COFF.  That's peculiar.  In fact, I really
1132 have no idea what the point of the line you want to remove is.
1133
1134 A typical COFF reloc subtracts the old value of the symbol and adds in
1135 the new value to the location in the object file (if it's a pc
1136 relative reloc it adds the difference between the symbol value and the
1137 location).  When relocating we need to preserve that property.
1138
1139 BFD handles this by setting the addend to the negative of the old
1140 value of the symbol.  Unfortunately it handles common symbols in a
1141 non-standard way (it doesn't subtract the old value) but that's a
1142 different story (we can't change it without losing backward
1143 compatibility with old object files) (coff-i386 does subtract the old
1144 value, to be compatible with existing coff-i386 targets, like SCO).
1145
1146 So everything works fine when not producing relocateable output.  When
1147 we are producing relocateable output, logically we should do exactly
1148 what we do when not producing relocateable output.  Therefore, your
1149 patch is correct.  In fact, it should probably always just set
1150 reloc_entry->addend to 0 for all cases, since it is, in fact, going to
1151 add the value into the object file.  This won't hurt the COFF code,
1152 which doesn't use the addend; I'm not sure what it will do to other
1153 formats (the thing to check for would be whether any formats both use
1154 the addend and set partial_inplace).
1155
1156 When I wanted to make coff-i386 produce relocateable output, I ran
1157 into the problem that you are running into: I wanted to remove that
1158 line.  Rather than risk it, I made the coff-i386 relocs use a special
1159 function; it's coff_i386_reloc in coff-i386.c.  The function
1160 specifically adds the addend field into the object file, knowing that
1161 bfd_install_relocation is not going to.  If you remove that line, then
1162 coff-i386.c will wind up adding the addend field in twice.  It's
1163 trivial to fix; it just needs to be done.
1164
1165 The problem with removing the line is just that it may break some
1166 working code.  With BFD it's hard to be sure of anything.  The right
1167 way to deal with this is simply to build and test at least all the
1168 supported COFF targets.  It should be straightforward if time and disk
1169 space consuming.  For each target:
1170     1) build the linker
1171     2) generate some executable, and link it using -r (I would
1172        probably use paranoia.o and link against newlib/libc.a, which
1173        for all the supported targets would be available in
1174        /usr/cygnus/progressive/H-host/target/lib/libc.a).
1175     3) make the change to reloc.c
1176     4) rebuild the linker
1177     5) repeat step 2
1178     6) if the resulting object files are the same, you have at least
1179        made it no worse
1180     7) if they are different you have to figure out which version is
1181        right
1182 */
1183           relocation -= reloc_entry->addend;
1184 #endif
1185           reloc_entry->addend = 0;
1186         }
1187       else
1188         {
1189           reloc_entry->addend = relocation;
1190         }
1191     }
1192
1193   /* FIXME: This overflow checking is incomplete, because the value
1194      might have overflowed before we get here.  For a correct check we
1195      need to compute the value in a size larger than bitsize, but we
1196      can't reasonably do that for a reloc the same size as a host
1197      machine word.
1198      FIXME: We should also do overflow checking on the result after
1199      adding in the value contained in the object file.  */
1200   if (howto->complain_on_overflow != complain_overflow_dont)
1201     flag = bfd_check_overflow (howto->complain_on_overflow,
1202                                howto->bitsize,
1203                                howto->rightshift,
1204                                bfd_arch_bits_per_address (abfd),
1205                                relocation);
1206
1207   /*
1208     Either we are relocating all the way, or we don't want to apply
1209     the relocation to the reloc entry (probably because there isn't
1210     any room in the output format to describe addends to relocs)
1211     */
1212
1213   /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
1214      (OSF version 1.3, compiler version 3.11).  It miscompiles the
1215      following program:
1216
1217      struct str
1218      {
1219        unsigned int i0;
1220      } s = { 0 };
1221
1222      int
1223      main ()
1224      {
1225        unsigned long x;
1226
1227        x = 0x100000000;
1228        x <<= (unsigned long) s.i0;
1229        if (x == 0)
1230          printf ("failed\n");
1231        else
1232          printf ("succeeded (%lx)\n", x);
1233      }
1234      */
1235
1236   relocation >>= (bfd_vma) howto->rightshift;
1237
1238   /* Shift everything up to where it's going to be used */
1239
1240   relocation <<= (bfd_vma) howto->bitpos;
1241
1242   /* Wait for the day when all have the mask in them */
1243
1244   /* What we do:
1245      i instruction to be left alone
1246      o offset within instruction
1247      r relocation offset to apply
1248      S src mask
1249      D dst mask
1250      N ~dst mask
1251      A part 1
1252      B part 2
1253      R result
1254
1255      Do this:
1256      i i i i i o o o o o        from bfd_get<size>
1257      and           S S S S S    to get the size offset we want
1258      +   r r r r r r r r r r  to get the final value to place
1259      and           D D D D D  to chop to right size
1260      -----------------------
1261      A A A A A
1262      And this:
1263      ...   i i i i i o o o o o  from bfd_get<size>
1264      and   N N N N N            get instruction
1265      -----------------------
1266      ...   B B B B B
1267
1268      And then:
1269      B B B B B
1270      or              A A A A A
1271      -----------------------
1272      R R R R R R R R R R        put into bfd_put<size>
1273      */
1274
1275 #define DOIT(x) \
1276   x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) +  relocation) & howto->dst_mask))
1277
1278   data = (bfd_byte *) data_start + (addr - data_start_offset);
1279
1280   switch (howto->size)
1281     {
1282     case 0:
1283       {
1284         char x = bfd_get_8 (abfd, (char *) data);
1285         DOIT (x);
1286         bfd_put_8 (abfd, x, (unsigned char *) data);
1287       }
1288       break;
1289
1290     case 1:
1291       {
1292         short x = bfd_get_16 (abfd, (bfd_byte *) data);
1293         DOIT (x);
1294         bfd_put_16 (abfd, x, (unsigned char *) data);
1295       }
1296       break;
1297     case 2:
1298       {
1299         long x = bfd_get_32 (abfd, (bfd_byte *) data);
1300         DOIT (x);
1301         bfd_put_32 (abfd, x, (bfd_byte *) data);
1302       }
1303       break;
1304     case -2:
1305       {
1306         long x = bfd_get_32 (abfd, (bfd_byte *) data);
1307         relocation = -relocation;
1308         DOIT (x);
1309         bfd_put_32 (abfd, x, (bfd_byte *) data);
1310       }
1311       break;
1312
1313     case 3:
1314       /* Do nothing */
1315       break;
1316
1317     case 4:
1318       {
1319         bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data);
1320         DOIT (x);
1321         bfd_put_64 (abfd, x, (bfd_byte *) data);
1322       }
1323       break;
1324     default:
1325       return bfd_reloc_other;
1326     }
1327
1328   return flag;
1329 }
1330
1331 /* This relocation routine is used by some of the backend linkers.
1332    They do not construct asymbol or arelent structures, so there is no
1333    reason for them to use bfd_perform_relocation.  Also,
1334    bfd_perform_relocation is so hacked up it is easier to write a new
1335    function than to try to deal with it.
1336
1337    This routine does a final relocation.  Whether it is useful for a
1338    relocateable link depends upon how the object format defines
1339    relocations.
1340
1341    FIXME: This routine ignores any special_function in the HOWTO,
1342    since the existing special_function values have been written for
1343    bfd_perform_relocation.
1344
1345    HOWTO is the reloc howto information.
1346    INPUT_BFD is the BFD which the reloc applies to.
1347    INPUT_SECTION is the section which the reloc applies to.
1348    CONTENTS is the contents of the section.
1349    ADDRESS is the address of the reloc within INPUT_SECTION.
1350    VALUE is the value of the symbol the reloc refers to.
1351    ADDEND is the addend of the reloc.  */
1352
1353 bfd_reloc_status_type
1354 _bfd_final_link_relocate (howto, input_bfd, input_section, contents, address,
1355                           value, addend)
1356      reloc_howto_type *howto;
1357      bfd *input_bfd;
1358      asection *input_section;
1359      bfd_byte *contents;
1360      bfd_vma address;
1361      bfd_vma value;
1362      bfd_vma addend;
1363 {
1364   bfd_vma relocation;
1365
1366   /* Sanity check the address.  */
1367   if (address > input_section->_raw_size)
1368     return bfd_reloc_outofrange;
1369
1370   /* This function assumes that we are dealing with a basic relocation
1371      against a symbol.  We want to compute the value of the symbol to
1372      relocate to.  This is just VALUE, the value of the symbol, plus
1373      ADDEND, any addend associated with the reloc.  */
1374   relocation = value + addend;
1375
1376   /* If the relocation is PC relative, we want to set RELOCATION to
1377      the distance between the symbol (currently in RELOCATION) and the
1378      location we are relocating.  Some targets (e.g., i386-aout)
1379      arrange for the contents of the section to be the negative of the
1380      offset of the location within the section; for such targets
1381      pcrel_offset is false.  Other targets (e.g., m88kbcs or ELF)
1382      simply leave the contents of the section as zero; for such
1383      targets pcrel_offset is true.  If pcrel_offset is false we do not
1384      need to subtract out the offset of the location within the
1385      section (which is just ADDRESS).  */
1386   if (howto->pc_relative)
1387     {
1388       relocation -= (input_section->output_section->vma
1389                      + input_section->output_offset);
1390       if (howto->pcrel_offset)
1391         relocation -= address;
1392     }
1393
1394   return _bfd_relocate_contents (howto, input_bfd, relocation,
1395                                  contents + address);
1396 }
1397
1398 /* Relocate a given location using a given value and howto.  */
1399
1400 bfd_reloc_status_type
1401 _bfd_relocate_contents (howto, input_bfd, relocation, location)
1402      reloc_howto_type *howto;
1403      bfd *input_bfd;
1404      bfd_vma relocation;
1405      bfd_byte *location;
1406 {
1407   int size;
1408   bfd_vma x;
1409   boolean overflow;
1410   unsigned int rightshift = howto->rightshift;
1411   unsigned int bitpos = howto->bitpos;
1412
1413   /* If the size is negative, negate RELOCATION.  This isn't very
1414      general.  */
1415   if (howto->size < 0)
1416     relocation = -relocation;
1417
1418   /* Get the value we are going to relocate.  */
1419   size = bfd_get_reloc_size (howto);
1420   switch (size)
1421     {
1422     default:
1423     case 0:
1424       abort ();
1425     case 1:
1426       x = bfd_get_8 (input_bfd, location);
1427       break;
1428     case 2:
1429       x = bfd_get_16 (input_bfd, location);
1430       break;
1431     case 4:
1432       x = bfd_get_32 (input_bfd, location);
1433       break;
1434     case 8:
1435 #ifdef BFD64
1436       x = bfd_get_64 (input_bfd, location);
1437 #else
1438       abort ();
1439 #endif
1440       break;
1441     }
1442
1443   /* Check for overflow.  FIXME: We may drop bits during the addition
1444      which we don't check for.  We must either check at every single
1445      operation, which would be tedious, or we must do the computations
1446      in a type larger than bfd_vma, which would be inefficient.  */
1447   overflow = false;
1448   if (howto->complain_on_overflow != complain_overflow_dont)
1449     {
1450       bfd_vma addrmask, fieldmask, signmask, ss;
1451       bfd_vma a, b, sum;
1452
1453       /* Get the values to be added together.  For signed and unsigned
1454          relocations, we assume that all values should be truncated to
1455          the size of an address.  For bitfields, all the bits matter.
1456          See also bfd_check_overflow.  */
1457       fieldmask = N_ONES (howto->bitsize);
1458       addrmask = N_ONES (bfd_arch_bits_per_address (input_bfd)) | fieldmask;
1459       a = relocation;
1460       b = x & howto->src_mask;
1461
1462       switch (howto->complain_on_overflow)
1463         {
1464         case complain_overflow_signed:
1465           a = (a & addrmask) >> rightshift;
1466
1467           /* If any sign bits are set, all sign bits must be set.
1468              That is, A must be a valid negative address after
1469              shifting.  */
1470           signmask = ~ (fieldmask >> 1);
1471           ss = a & signmask;
1472           if (ss != 0 && ss != ((addrmask >> rightshift) & signmask))
1473             overflow = true;
1474
1475           /* We only need this next bit of code if the sign bit of B
1476              is below the sign bit of A.  This would only happen if
1477              SRC_MASK had fewer bits than BITSIZE.  Note that if
1478              SRC_MASK has more bits than BITSIZE, we can get into
1479              trouble; we would need to verify that B is in range, as
1480              we do for A above.  */
1481           signmask = ((~ howto->src_mask) >> 1) & howto->src_mask;
1482           if ((b & signmask) != 0)
1483             {
1484               /* Set all the bits above the sign bit.  */
1485               b -= signmask <<= 1;
1486             }
1487
1488           b = (b & addrmask) >> bitpos;
1489
1490           /* Now we can do the addition.  */
1491           sum = a + b;
1492
1493           /* See if the result has the correct sign.  Bits above the
1494              sign bit are junk now; ignore them.  If the sum is
1495              positive, make sure we did not have all negative inputs;
1496              if the sum is negative, make sure we did not have all
1497              positive inputs.  The test below looks only at the sign
1498              bits, and it really just
1499                  SIGN (A) == SIGN (B) && SIGN (A) != SIGN (SUM)
1500              */
1501           signmask = (fieldmask >> 1) + 1;
1502           if (((~ (a ^ b)) & (a ^ sum)) & signmask)
1503             overflow = true;
1504
1505           break;
1506
1507         case complain_overflow_unsigned:
1508           /* Checking for an unsigned overflow is relatively easy:
1509              trim the addresses and add, and trim the result as well.
1510              Overflow is normally indicated when the result does not
1511              fit in the field.  However, we also need to consider the
1512              case when, e.g., fieldmask is 0x7fffffff or smaller, an
1513              input is 0x80000000, and bfd_vma is only 32 bits; then we
1514              will get sum == 0, but there is an overflow, since the
1515              inputs did not fit in the field.  Instead of doing a
1516              separate test, we can check for this by or-ing in the
1517              operands when testing for the sum overflowing its final
1518              field.  */
1519           a = (a & addrmask) >> rightshift;
1520           b = (b & addrmask) >> bitpos;
1521           sum = (a + b) & addrmask;
1522           if ((a | b | sum) & ~ fieldmask)
1523             overflow = true;
1524
1525           break;
1526
1527         case complain_overflow_bitfield:
1528           /* Much like unsigned, except no trimming with addrmask.  In
1529              addition, the sum overflows if there is a carry out of
1530              the bfd_vma, i.e., the sum is less than either input
1531              operand.  */
1532           a >>= rightshift;
1533           b >>= bitpos;
1534
1535           /* Bitfields are sometimes used for signed numbers; for
1536              example, a 13-bit field sometimes represents values in
1537              0..8191 and sometimes represents values in -4096..4095.
1538              If the field is signed and a is -4095 (0x1001) and b is
1539              -1 (0x1fff), the sum is -4096 (0x1000), but (0x1001 +
1540              0x1fff is 0x3000).  It's not clear how to handle this
1541              everywhere, since there is not way to know how many bits
1542              are significant in the relocation, but the original code
1543              assumed that it was fully sign extended, and we will keep
1544              that assumption.  */
1545           signmask = (fieldmask >> 1) + 1;
1546
1547           if ((a & ~ fieldmask) != 0)
1548             {
1549               /* Some bits out of the field are set.  This might not
1550                  be a problem: if this is a signed bitfield, it is OK
1551                  iff all the high bits are set, including the sign
1552                  bit.  We'll try setting all but the most significant
1553                  bit in the original relocation value: if this is all
1554                  ones, we are OK, assuming a signed bitfield.  */
1555               ss = (signmask << rightshift) - 1;
1556               if ((ss | relocation) != ~ (bfd_vma) 0)
1557                 overflow = true;
1558               a &= fieldmask;
1559             }
1560
1561           /* We just assume (b & ~ fieldmask) == 0.  */
1562
1563           /* We explicitly permit wrap around if this relocation
1564              covers the high bit of an address.  The Linux kernel
1565              relies on it, and it is the only way to write assembler
1566              code which can run when loaded at a location 0x80000000
1567              away from the location at which it is linked.  */
1568           if (howto->bitsize + rightshift
1569               == bfd_arch_bits_per_address (input_bfd))
1570             break;
1571
1572           sum = a + b;
1573           if (sum < a || (sum & ~ fieldmask) != 0)
1574             {
1575               /* There was a carry out, or the field overflow.  Test
1576                  for signed operands again.  Here is the overflow test
1577                  is as for complain_overflow_signed.  */
1578               if (((~ (a ^ b)) & (a ^ sum)) & signmask)
1579                 overflow = true;
1580             }
1581
1582           break;
1583
1584         default:
1585           abort ();
1586         }
1587     }
1588
1589   /* Put RELOCATION in the right bits.  */
1590   relocation >>= (bfd_vma) rightshift;
1591   relocation <<= (bfd_vma) bitpos;
1592
1593   /* Add RELOCATION to the right bits of X.  */
1594   x = ((x & ~howto->dst_mask)
1595        | (((x & howto->src_mask) + relocation) & howto->dst_mask));
1596
1597   /* Put the relocated value back in the object file.  */
1598   switch (size)
1599     {
1600     default:
1601     case 0:
1602       abort ();
1603     case 1:
1604       bfd_put_8 (input_bfd, x, location);
1605       break;
1606     case 2:
1607       bfd_put_16 (input_bfd, x, location);
1608       break;
1609     case 4:
1610       bfd_put_32 (input_bfd, x, location);
1611       break;
1612     case 8:
1613 #ifdef BFD64
1614       bfd_put_64 (input_bfd, x, location);
1615 #else
1616       abort ();
1617 #endif
1618       break;
1619     }
1620
1621   return overflow ? bfd_reloc_overflow : bfd_reloc_ok;
1622 }
1623
1624 /*
1625 DOCDD
1626 INODE
1627         howto manager,  , typedef arelent, Relocations
1628
1629 SECTION
1630         The howto manager
1631
1632         When an application wants to create a relocation, but doesn't
1633         know what the target machine might call it, it can find out by
1634         using this bit of code.
1635
1636 */
1637
1638 /*
1639 TYPEDEF
1640         bfd_reloc_code_type
1641
1642 DESCRIPTION
1643         The insides of a reloc code.  The idea is that, eventually, there
1644         will be one enumerator for every type of relocation we ever do.
1645         Pass one of these values to <<bfd_reloc_type_lookup>>, and it'll
1646         return a howto pointer.
1647
1648         This does mean that the application must determine the correct
1649         enumerator value; you can't get a howto pointer from a random set
1650         of attributes.
1651
1652 SENUM
1653    bfd_reloc_code_real
1654
1655 ENUM
1656   BFD_RELOC_64
1657 ENUMX
1658   BFD_RELOC_32
1659 ENUMX
1660   BFD_RELOC_26
1661 ENUMX
1662   BFD_RELOC_24
1663 ENUMX
1664   BFD_RELOC_16
1665 ENUMX
1666   BFD_RELOC_14
1667 ENUMX
1668   BFD_RELOC_8
1669 ENUMDOC
1670   Basic absolute relocations of N bits.
1671
1672 ENUM
1673   BFD_RELOC_64_PCREL
1674 ENUMX
1675   BFD_RELOC_32_PCREL
1676 ENUMX
1677   BFD_RELOC_24_PCREL
1678 ENUMX
1679   BFD_RELOC_16_PCREL
1680 ENUMX
1681   BFD_RELOC_12_PCREL
1682 ENUMX
1683   BFD_RELOC_8_PCREL
1684 ENUMDOC
1685   PC-relative relocations.  Sometimes these are relative to the address
1686 of the relocation itself; sometimes they are relative to the start of
1687 the section containing the relocation.  It depends on the specific target.
1688
1689 The 24-bit relocation is used in some Intel 960 configurations.
1690
1691 ENUM
1692   BFD_RELOC_32_GOT_PCREL
1693 ENUMX
1694   BFD_RELOC_16_GOT_PCREL
1695 ENUMX
1696   BFD_RELOC_8_GOT_PCREL
1697 ENUMX
1698   BFD_RELOC_32_GOTOFF
1699 ENUMX
1700   BFD_RELOC_16_GOTOFF
1701 ENUMX
1702   BFD_RELOC_LO16_GOTOFF
1703 ENUMX
1704   BFD_RELOC_HI16_GOTOFF
1705 ENUMX
1706   BFD_RELOC_HI16_S_GOTOFF
1707 ENUMX
1708   BFD_RELOC_8_GOTOFF
1709 ENUMX
1710   BFD_RELOC_32_PLT_PCREL
1711 ENUMX
1712   BFD_RELOC_24_PLT_PCREL
1713 ENUMX
1714   BFD_RELOC_16_PLT_PCREL
1715 ENUMX
1716   BFD_RELOC_8_PLT_PCREL
1717 ENUMX
1718   BFD_RELOC_32_PLTOFF
1719 ENUMX
1720   BFD_RELOC_16_PLTOFF
1721 ENUMX
1722   BFD_RELOC_LO16_PLTOFF
1723 ENUMX
1724   BFD_RELOC_HI16_PLTOFF
1725 ENUMX
1726   BFD_RELOC_HI16_S_PLTOFF
1727 ENUMX
1728   BFD_RELOC_8_PLTOFF
1729 ENUMDOC
1730   For ELF.
1731
1732 ENUM
1733   BFD_RELOC_68K_GLOB_DAT
1734 ENUMX
1735   BFD_RELOC_68K_JMP_SLOT
1736 ENUMX
1737   BFD_RELOC_68K_RELATIVE
1738 ENUMDOC
1739   Relocations used by 68K ELF.
1740
1741 ENUM
1742   BFD_RELOC_32_BASEREL
1743 ENUMX
1744   BFD_RELOC_16_BASEREL
1745 ENUMX
1746   BFD_RELOC_LO16_BASEREL
1747 ENUMX
1748   BFD_RELOC_HI16_BASEREL
1749 ENUMX
1750   BFD_RELOC_HI16_S_BASEREL
1751 ENUMX
1752   BFD_RELOC_8_BASEREL
1753 ENUMX
1754   BFD_RELOC_RVA
1755 ENUMDOC
1756   Linkage-table relative.
1757
1758 ENUM
1759   BFD_RELOC_8_FFnn
1760 ENUMDOC
1761   Absolute 8-bit relocation, but used to form an address like 0xFFnn.
1762
1763 ENUM
1764   BFD_RELOC_32_PCREL_S2
1765 ENUMX
1766   BFD_RELOC_16_PCREL_S2
1767 ENUMX
1768   BFD_RELOC_23_PCREL_S2
1769 ENUMDOC
1770   These PC-relative relocations are stored as word displacements --
1771 i.e., byte displacements shifted right two bits.  The 30-bit word
1772 displacement (<<32_PCREL_S2>> -- 32 bits, shifted 2) is used on the
1773 SPARC.  (SPARC tools generally refer to this as <<WDISP30>>.)  The
1774 signed 16-bit displacement is used on the MIPS, and the 23-bit
1775 displacement is used on the Alpha.
1776
1777 ENUM
1778   BFD_RELOC_HI22
1779 ENUMX
1780   BFD_RELOC_LO10
1781 ENUMDOC
1782   High 22 bits and low 10 bits of 32-bit value, placed into lower bits of
1783 the target word.  These are used on the SPARC.
1784
1785 ENUM
1786   BFD_RELOC_GPREL16
1787 ENUMX
1788   BFD_RELOC_GPREL32
1789 ENUMDOC
1790   For systems that allocate a Global Pointer register, these are
1791 displacements off that register.  These relocation types are
1792 handled specially, because the value the register will have is
1793 decided relatively late.
1794
1795
1796 ENUM
1797   BFD_RELOC_I960_CALLJ
1798 ENUMDOC
1799   Reloc types used for i960/b.out.
1800
1801 ENUM
1802   BFD_RELOC_NONE
1803 ENUMX
1804   BFD_RELOC_SPARC_WDISP22
1805 ENUMX
1806   BFD_RELOC_SPARC22
1807 ENUMX
1808   BFD_RELOC_SPARC13
1809 ENUMX
1810   BFD_RELOC_SPARC_GOT10
1811 ENUMX
1812   BFD_RELOC_SPARC_GOT13
1813 ENUMX
1814   BFD_RELOC_SPARC_GOT22
1815 ENUMX
1816   BFD_RELOC_SPARC_PC10
1817 ENUMX
1818   BFD_RELOC_SPARC_PC22
1819 ENUMX
1820   BFD_RELOC_SPARC_WPLT30
1821 ENUMX
1822   BFD_RELOC_SPARC_COPY
1823 ENUMX
1824   BFD_RELOC_SPARC_GLOB_DAT
1825 ENUMX
1826   BFD_RELOC_SPARC_JMP_SLOT
1827 ENUMX
1828   BFD_RELOC_SPARC_RELATIVE
1829 ENUMX
1830   BFD_RELOC_SPARC_UA32
1831 ENUMDOC
1832   SPARC ELF relocations.  There is probably some overlap with other
1833   relocation types already defined.
1834
1835 ENUM
1836   BFD_RELOC_SPARC_BASE13
1837 ENUMX
1838   BFD_RELOC_SPARC_BASE22
1839 ENUMDOC
1840   I think these are specific to SPARC a.out (e.g., Sun 4).
1841
1842 ENUMEQ
1843   BFD_RELOC_SPARC_64
1844   BFD_RELOC_64
1845 ENUMX
1846   BFD_RELOC_SPARC_10
1847 ENUMX
1848   BFD_RELOC_SPARC_11
1849 ENUMX
1850   BFD_RELOC_SPARC_OLO10
1851 ENUMX
1852   BFD_RELOC_SPARC_HH22
1853 ENUMX
1854   BFD_RELOC_SPARC_HM10
1855 ENUMX
1856   BFD_RELOC_SPARC_LM22
1857 ENUMX
1858   BFD_RELOC_SPARC_PC_HH22
1859 ENUMX
1860   BFD_RELOC_SPARC_PC_HM10
1861 ENUMX
1862   BFD_RELOC_SPARC_PC_LM22
1863 ENUMX
1864   BFD_RELOC_SPARC_WDISP16
1865 ENUMX
1866   BFD_RELOC_SPARC_WDISP19
1867 ENUMX
1868   BFD_RELOC_SPARC_7
1869 ENUMX
1870   BFD_RELOC_SPARC_6
1871 ENUMX
1872   BFD_RELOC_SPARC_5
1873 ENUMEQX
1874   BFD_RELOC_SPARC_DISP64
1875   BFD_RELOC_64_PCREL
1876 ENUMX
1877   BFD_RELOC_SPARC_PLT64
1878 ENUMX
1879   BFD_RELOC_SPARC_HIX22
1880 ENUMX
1881   BFD_RELOC_SPARC_LOX10
1882 ENUMX
1883   BFD_RELOC_SPARC_H44
1884 ENUMX
1885   BFD_RELOC_SPARC_M44
1886 ENUMX
1887   BFD_RELOC_SPARC_L44
1888 ENUMX
1889   BFD_RELOC_SPARC_REGISTER
1890 ENUMDOC
1891   SPARC64 relocations
1892
1893 ENUM
1894   BFD_RELOC_SPARC_REV32
1895 ENUMDOC
1896   SPARC little endian relocation
1897
1898 ENUM
1899   BFD_RELOC_ALPHA_GPDISP_HI16
1900 ENUMDOC
1901   Alpha ECOFF and ELF relocations.  Some of these treat the symbol or
1902      "addend" in some special way.
1903   For GPDISP_HI16 ("gpdisp") relocations, the symbol is ignored when
1904      writing; when reading, it will be the absolute section symbol.  The
1905      addend is the displacement in bytes of the "lda" instruction from
1906      the "ldah" instruction (which is at the address of this reloc).
1907 ENUM
1908   BFD_RELOC_ALPHA_GPDISP_LO16
1909 ENUMDOC
1910   For GPDISP_LO16 ("ignore") relocations, the symbol is handled as
1911      with GPDISP_HI16 relocs.  The addend is ignored when writing the
1912      relocations out, and is filled in with the file's GP value on
1913      reading, for convenience.
1914
1915 ENUM
1916   BFD_RELOC_ALPHA_GPDISP
1917 ENUMDOC
1918   The ELF GPDISP relocation is exactly the same as the GPDISP_HI16
1919      relocation except that there is no accompanying GPDISP_LO16
1920      relocation.
1921
1922 ENUM
1923   BFD_RELOC_ALPHA_LITERAL
1924 ENUMX
1925   BFD_RELOC_ALPHA_ELF_LITERAL
1926 ENUMX
1927   BFD_RELOC_ALPHA_LITUSE
1928 ENUMDOC
1929   The Alpha LITERAL/LITUSE relocs are produced by a symbol reference;
1930      the assembler turns it into a LDQ instruction to load the address of
1931      the symbol, and then fills in a register in the real instruction.
1932
1933      The LITERAL reloc, at the LDQ instruction, refers to the .lita
1934      section symbol.  The addend is ignored when writing, but is filled
1935      in with the file's GP value on reading, for convenience, as with the
1936      GPDISP_LO16 reloc.
1937
1938      The ELF_LITERAL reloc is somewhere between 16_GOTOFF and GPDISP_LO16.
1939      It should refer to the symbol to be referenced, as with 16_GOTOFF,
1940      but it generates output not based on the position within the .got
1941      section, but relative to the GP value chosen for the file during the
1942      final link stage.
1943
1944      The LITUSE reloc, on the instruction using the loaded address, gives
1945      information to the linker that it might be able to use to optimize
1946      away some literal section references.  The symbol is ignored (read
1947      as the absolute section symbol), and the "addend" indicates the type
1948      of instruction using the register:
1949               1 - "memory" fmt insn
1950               2 - byte-manipulation (byte offset reg)
1951               3 - jsr (target of branch)
1952
1953      The GNU linker currently doesn't do any of this optimizing.
1954
1955 ENUM
1956   BFD_RELOC_ALPHA_HINT
1957 ENUMDOC
1958   The HINT relocation indicates a value that should be filled into the
1959      "hint" field of a jmp/jsr/ret instruction, for possible branch-
1960      prediction logic which may be provided on some processors.
1961
1962 ENUM
1963   BFD_RELOC_ALPHA_LINKAGE
1964 ENUMDOC
1965   The LINKAGE relocation outputs a linkage pair in the object file,
1966      which is filled by the linker.
1967
1968 ENUM
1969   BFD_RELOC_ALPHA_CODEADDR
1970 ENUMDOC
1971   The CODEADDR relocation outputs a STO_CA in the object file,
1972      which is filled by the linker.
1973
1974 ENUM
1975   BFD_RELOC_MIPS_JMP
1976 ENUMDOC
1977   Bits 27..2 of the relocation address shifted right 2 bits;
1978      simple reloc otherwise.
1979
1980 ENUM
1981   BFD_RELOC_MIPS16_JMP
1982 ENUMDOC
1983   The MIPS16 jump instruction.
1984
1985 ENUM
1986   BFD_RELOC_MIPS16_GPREL
1987 ENUMDOC
1988   MIPS16 GP relative reloc.
1989
1990 ENUM
1991   BFD_RELOC_HI16
1992 ENUMDOC
1993   High 16 bits of 32-bit value; simple reloc.
1994 ENUM
1995   BFD_RELOC_HI16_S
1996 ENUMDOC
1997   High 16 bits of 32-bit value but the low 16 bits will be sign
1998      extended and added to form the final result.  If the low 16
1999      bits form a negative number, we need to add one to the high value
2000      to compensate for the borrow when the low bits are added.
2001 ENUM
2002   BFD_RELOC_LO16
2003 ENUMDOC
2004   Low 16 bits.
2005 ENUM
2006   BFD_RELOC_PCREL_HI16_S
2007 ENUMDOC
2008   Like BFD_RELOC_HI16_S, but PC relative.
2009 ENUM
2010   BFD_RELOC_PCREL_LO16
2011 ENUMDOC
2012   Like BFD_RELOC_LO16, but PC relative.
2013
2014 ENUMEQ
2015   BFD_RELOC_MIPS_GPREL
2016   BFD_RELOC_GPREL16
2017 ENUMDOC
2018   Relocation relative to the global pointer.
2019
2020 ENUM
2021   BFD_RELOC_MIPS_LITERAL
2022 ENUMDOC
2023   Relocation against a MIPS literal section.
2024
2025 ENUM
2026   BFD_RELOC_MIPS_GOT16
2027 ENUMX
2028   BFD_RELOC_MIPS_CALL16
2029 ENUMEQX
2030   BFD_RELOC_MIPS_GPREL32
2031   BFD_RELOC_GPREL32
2032 ENUMX
2033   BFD_RELOC_MIPS_GOT_HI16
2034 ENUMX
2035   BFD_RELOC_MIPS_GOT_LO16
2036 ENUMX
2037   BFD_RELOC_MIPS_CALL_HI16
2038 ENUMX
2039   BFD_RELOC_MIPS_CALL_LO16
2040 ENUMX
2041   BFD_RELOC_MIPS_SUB
2042 ENUMX
2043   BFD_RELOC_MIPS_GOT_PAGE
2044 ENUMX
2045   BFD_RELOC_MIPS_GOT_OFST
2046 ENUMX
2047   BFD_RELOC_MIPS_GOT_DISP
2048 COMMENT
2049 ENUMDOC
2050   MIPS ELF relocations.
2051
2052 COMMENT
2053
2054 ENUM
2055   BFD_RELOC_386_GOT32
2056 ENUMX
2057   BFD_RELOC_386_PLT32
2058 ENUMX
2059   BFD_RELOC_386_COPY
2060 ENUMX
2061   BFD_RELOC_386_GLOB_DAT
2062 ENUMX
2063   BFD_RELOC_386_JUMP_SLOT
2064 ENUMX
2065   BFD_RELOC_386_RELATIVE
2066 ENUMX
2067   BFD_RELOC_386_GOTOFF
2068 ENUMX
2069   BFD_RELOC_386_GOTPC
2070 ENUMDOC
2071   i386/elf relocations
2072
2073 ENUM
2074   BFD_RELOC_NS32K_IMM_8
2075 ENUMX
2076   BFD_RELOC_NS32K_IMM_16
2077 ENUMX
2078   BFD_RELOC_NS32K_IMM_32
2079 ENUMX
2080   BFD_RELOC_NS32K_IMM_8_PCREL
2081 ENUMX
2082   BFD_RELOC_NS32K_IMM_16_PCREL
2083 ENUMX
2084   BFD_RELOC_NS32K_IMM_32_PCREL
2085 ENUMX
2086   BFD_RELOC_NS32K_DISP_8
2087 ENUMX
2088   BFD_RELOC_NS32K_DISP_16
2089 ENUMX
2090   BFD_RELOC_NS32K_DISP_32
2091 ENUMX
2092   BFD_RELOC_NS32K_DISP_8_PCREL
2093 ENUMX
2094   BFD_RELOC_NS32K_DISP_16_PCREL
2095 ENUMX
2096   BFD_RELOC_NS32K_DISP_32_PCREL
2097 ENUMDOC
2098   ns32k relocations
2099
2100 ENUM
2101   BFD_RELOC_PPC_B26
2102 ENUMX
2103   BFD_RELOC_PPC_BA26
2104 ENUMX
2105   BFD_RELOC_PPC_TOC16
2106 ENUMX
2107   BFD_RELOC_PPC_B16
2108 ENUMX
2109   BFD_RELOC_PPC_B16_BRTAKEN
2110 ENUMX
2111   BFD_RELOC_PPC_B16_BRNTAKEN
2112 ENUMX
2113   BFD_RELOC_PPC_BA16
2114 ENUMX
2115   BFD_RELOC_PPC_BA16_BRTAKEN
2116 ENUMX
2117   BFD_RELOC_PPC_BA16_BRNTAKEN
2118 ENUMX
2119   BFD_RELOC_PPC_COPY
2120 ENUMX
2121   BFD_RELOC_PPC_GLOB_DAT
2122 ENUMX
2123   BFD_RELOC_PPC_JMP_SLOT
2124 ENUMX
2125   BFD_RELOC_PPC_RELATIVE
2126 ENUMX
2127   BFD_RELOC_PPC_LOCAL24PC
2128 ENUMX
2129   BFD_RELOC_PPC_EMB_NADDR32
2130 ENUMX
2131   BFD_RELOC_PPC_EMB_NADDR16
2132 ENUMX
2133   BFD_RELOC_PPC_EMB_NADDR16_LO
2134 ENUMX
2135   BFD_RELOC_PPC_EMB_NADDR16_HI
2136 ENUMX
2137   BFD_RELOC_PPC_EMB_NADDR16_HA
2138 ENUMX
2139   BFD_RELOC_PPC_EMB_SDAI16
2140 ENUMX
2141   BFD_RELOC_PPC_EMB_SDA2I16
2142 ENUMX
2143   BFD_RELOC_PPC_EMB_SDA2REL
2144 ENUMX
2145   BFD_RELOC_PPC_EMB_SDA21
2146 ENUMX
2147   BFD_RELOC_PPC_EMB_MRKREF
2148 ENUMX
2149   BFD_RELOC_PPC_EMB_RELSEC16
2150 ENUMX
2151   BFD_RELOC_PPC_EMB_RELST_LO
2152 ENUMX
2153   BFD_RELOC_PPC_EMB_RELST_HI
2154 ENUMX
2155   BFD_RELOC_PPC_EMB_RELST_HA
2156 ENUMX
2157   BFD_RELOC_PPC_EMB_BIT_FLD
2158 ENUMX
2159   BFD_RELOC_PPC_EMB_RELSDA
2160 ENUMDOC
2161   Power(rs6000) and PowerPC relocations.
2162
2163 ENUM
2164   BFD_RELOC_CTOR
2165 ENUMDOC
2166   The type of reloc used to build a contructor table - at the moment
2167   probably a 32 bit wide absolute relocation, but the target can choose.
2168   It generally does map to one of the other relocation types.
2169
2170 ENUM
2171   BFD_RELOC_ARM_PCREL_BRANCH
2172 ENUMDOC
2173   ARM 26 bit pc-relative branch.  The lowest two bits must be zero and are
2174   not stored in the instruction.
2175 ENUM
2176   BFD_RELOC_ARM_IMMEDIATE
2177 ENUMX
2178   BFD_RELOC_ARM_OFFSET_IMM
2179 ENUMX
2180   BFD_RELOC_ARM_SHIFT_IMM
2181 ENUMX
2182   BFD_RELOC_ARM_SWI
2183 ENUMX
2184   BFD_RELOC_ARM_MULTI
2185 ENUMX
2186   BFD_RELOC_ARM_CP_OFF_IMM
2187 ENUMX
2188   BFD_RELOC_ARM_ADR_IMM
2189 ENUMX
2190   BFD_RELOC_ARM_LDR_IMM
2191 ENUMX
2192   BFD_RELOC_ARM_LITERAL
2193 ENUMX
2194   BFD_RELOC_ARM_IN_POOL
2195 ENUMX
2196   BFD_RELOC_ARM_OFFSET_IMM8
2197 ENUMX
2198   BFD_RELOC_ARM_HWLITERAL
2199 ENUMX
2200   BFD_RELOC_ARM_THUMB_ADD
2201 ENUMX
2202   BFD_RELOC_ARM_THUMB_IMM
2203 ENUMX
2204   BFD_RELOC_ARM_THUMB_SHIFT
2205 ENUMX
2206   BFD_RELOC_ARM_THUMB_OFFSET
2207 ENUMX
2208   BFD_RELOC_ARM_GOT12
2209 ENUMX
2210   BFD_RELOC_ARM_GOT32
2211 ENUMX
2212   BFD_RELOC_ARM_JUMP_SLOT
2213 ENUMX
2214   BFD_RELOC_ARM_COPY
2215 ENUMX
2216   BFD_RELOC_ARM_GLOB_DAT
2217 ENUMX
2218   BFD_RELOC_ARM_PLT32
2219 ENUMX
2220   BFD_RELOC_ARM_RELATIVE
2221 ENUMX
2222   BFD_RELOC_ARM_GOTOFF
2223 ENUMX
2224   BFD_RELOC_ARM_GOTPC
2225 ENUMDOC
2226   These relocs are only used within the ARM assembler.  They are not
2227   (at present) written to any object files.
2228
2229 ENUM
2230   BFD_RELOC_SH_PCDISP8BY2
2231 ENUMX
2232   BFD_RELOC_SH_PCDISP12BY2
2233 ENUMX
2234   BFD_RELOC_SH_IMM4
2235 ENUMX
2236   BFD_RELOC_SH_IMM4BY2
2237 ENUMX
2238   BFD_RELOC_SH_IMM4BY4
2239 ENUMX
2240   BFD_RELOC_SH_IMM8
2241 ENUMX
2242   BFD_RELOC_SH_IMM8BY2
2243 ENUMX
2244   BFD_RELOC_SH_IMM8BY4
2245 ENUMX
2246   BFD_RELOC_SH_PCRELIMM8BY2
2247 ENUMX
2248   BFD_RELOC_SH_PCRELIMM8BY4
2249 ENUMX
2250   BFD_RELOC_SH_SWITCH16
2251 ENUMX
2252   BFD_RELOC_SH_SWITCH32
2253 ENUMX
2254   BFD_RELOC_SH_USES
2255 ENUMX
2256   BFD_RELOC_SH_COUNT
2257 ENUMX
2258   BFD_RELOC_SH_ALIGN
2259 ENUMX
2260   BFD_RELOC_SH_CODE
2261 ENUMX
2262   BFD_RELOC_SH_DATA
2263 ENUMX
2264   BFD_RELOC_SH_LABEL
2265 ENUMDOC
2266   Hitachi SH relocs.  Not all of these appear in object files.
2267
2268 ENUM
2269   BFD_RELOC_THUMB_PCREL_BRANCH9
2270 ENUMX
2271   BFD_RELOC_THUMB_PCREL_BRANCH12
2272 ENUMX
2273   BFD_RELOC_THUMB_PCREL_BRANCH23
2274 ENUMDOC
2275   Thumb 23-, 12- and 9-bit pc-relative branches.  The lowest bit must
2276   be zero and is not stored in the instruction.
2277
2278 ENUM
2279   BFD_RELOC_ARC_B22_PCREL
2280 ENUMDOC
2281   Argonaut RISC Core (ARC) relocs.
2282   ARC 22 bit pc-relative branch.  The lowest two bits must be zero and are
2283   not stored in the instruction.  The high 20 bits are installed in bits 26
2284   through 7 of the instruction.
2285 ENUM
2286   BFD_RELOC_ARC_B26
2287 ENUMDOC
2288   ARC 26 bit absolute branch.  The lowest two bits must be zero and are not
2289   stored in the instruction.  The high 24 bits are installed in bits 23
2290   through 0.
2291
2292 ENUM
2293   BFD_RELOC_D10V_10_PCREL_R
2294 ENUMDOC
2295   Mitsubishi D10V relocs.
2296   This is a 10-bit reloc with the right 2 bits
2297   assumed to be 0.
2298 ENUM
2299   BFD_RELOC_D10V_10_PCREL_L
2300 ENUMDOC
2301   Mitsubishi D10V relocs.
2302   This is a 10-bit reloc with the right 2 bits
2303   assumed to be 0.  This is the same as the previous reloc
2304   except it is in the left container, i.e.,
2305   shifted left 15 bits.
2306 ENUM
2307   BFD_RELOC_D10V_18
2308 ENUMDOC
2309   This is an 18-bit reloc with the right 2 bits
2310   assumed to be 0.
2311 ENUM
2312   BFD_RELOC_D10V_18_PCREL
2313 ENUMDOC
2314   This is an 18-bit reloc with the right 2 bits
2315   assumed to be 0.
2316
2317 ENUM
2318   BFD_RELOC_D30V_6
2319 ENUMDOC
2320   Mitsubishi D30V relocs.
2321   This is a 6-bit absolute reloc.
2322 ENUM
2323   BFD_RELOC_D30V_9_PCREL
2324 ENUMDOC
2325   This is a 6-bit pc-relative reloc with
2326   the right 3 bits assumed to be 0.
2327 ENUM
2328   BFD_RELOC_D30V_9_PCREL_R
2329 ENUMDOC
2330   This is a 6-bit pc-relative reloc with
2331   the right 3 bits assumed to be 0. Same
2332   as the previous reloc but on the right side
2333   of the container.
2334 ENUM
2335   BFD_RELOC_D30V_15
2336 ENUMDOC
2337   This is a 12-bit absolute reloc with the
2338   right 3 bitsassumed to be 0.
2339 ENUM
2340   BFD_RELOC_D30V_15_PCREL
2341 ENUMDOC
2342   This is a 12-bit pc-relative reloc with
2343   the right 3 bits assumed to be 0.
2344 ENUM
2345   BFD_RELOC_D30V_15_PCREL_R
2346 ENUMDOC
2347   This is a 12-bit pc-relative reloc with
2348   the right 3 bits assumed to be 0. Same
2349   as the previous reloc but on the right side
2350   of the container.
2351 ENUM
2352   BFD_RELOC_D30V_21
2353 ENUMDOC
2354   This is an 18-bit absolute reloc with
2355   the right 3 bits assumed to be 0.
2356 ENUM
2357   BFD_RELOC_D30V_21_PCREL
2358 ENUMDOC
2359   This is an 18-bit pc-relative reloc with
2360   the right 3 bits assumed to be 0.
2361 ENUM
2362   BFD_RELOC_D30V_21_PCREL_R
2363 ENUMDOC
2364   This is an 18-bit pc-relative reloc with
2365   the right 3 bits assumed to be 0. Same
2366   as the previous reloc but on the right side
2367   of the container.
2368 ENUM
2369   BFD_RELOC_D30V_32
2370 ENUMDOC
2371   This is a 32-bit absolute reloc.
2372 ENUM
2373   BFD_RELOC_D30V_32_PCREL
2374 ENUMDOC
2375   This is a 32-bit pc-relative reloc.
2376
2377 ENUM
2378   BFD_RELOC_M32R_24
2379 ENUMDOC
2380   Mitsubishi M32R relocs.
2381   This is a 24 bit absolute address.
2382 ENUM
2383   BFD_RELOC_M32R_10_PCREL
2384 ENUMDOC
2385   This is a 10-bit pc-relative reloc with the right 2 bits assumed to be 0.
2386 ENUM
2387   BFD_RELOC_M32R_18_PCREL
2388 ENUMDOC
2389   This is an 18-bit reloc with the right 2 bits assumed to be 0.
2390 ENUM
2391   BFD_RELOC_M32R_26_PCREL
2392 ENUMDOC
2393   This is a 26-bit reloc with the right 2 bits assumed to be 0.
2394 ENUM
2395   BFD_RELOC_M32R_HI16_ULO
2396 ENUMDOC
2397   This is a 16-bit reloc containing the high 16 bits of an address
2398   used when the lower 16 bits are treated as unsigned.
2399 ENUM
2400   BFD_RELOC_M32R_HI16_SLO
2401 ENUMDOC
2402   This is a 16-bit reloc containing the high 16 bits of an address
2403   used when the lower 16 bits are treated as signed.
2404 ENUM
2405   BFD_RELOC_M32R_LO16
2406 ENUMDOC
2407   This is a 16-bit reloc containing the lower 16 bits of an address.
2408 ENUM
2409   BFD_RELOC_M32R_SDA16
2410 ENUMDOC
2411   This is a 16-bit reloc containing the small data area offset for use in
2412   add3, load, and store instructions.
2413
2414 ENUM
2415   BFD_RELOC_V850_9_PCREL
2416 ENUMDOC
2417   This is a 9-bit reloc
2418 ENUM
2419   BFD_RELOC_V850_22_PCREL
2420 ENUMDOC
2421   This is a 22-bit reloc
2422
2423 ENUM
2424   BFD_RELOC_V850_SDA_16_16_OFFSET
2425 ENUMDOC
2426   This is a 16 bit offset from the short data area pointer.
2427 ENUM
2428   BFD_RELOC_V850_SDA_15_16_OFFSET
2429 ENUMDOC
2430   This is a 16 bit offset (of which only 15 bits are used) from the
2431   short data area pointer.
2432 ENUM
2433   BFD_RELOC_V850_ZDA_16_16_OFFSET
2434 ENUMDOC
2435   This is a 16 bit offset from the zero data area pointer.
2436 ENUM
2437   BFD_RELOC_V850_ZDA_15_16_OFFSET
2438 ENUMDOC
2439   This is a 16 bit offset (of which only 15 bits are used) from the
2440   zero data area pointer.
2441 ENUM
2442   BFD_RELOC_V850_TDA_6_8_OFFSET
2443 ENUMDOC
2444   This is an 8 bit offset (of which only 6 bits are used) from the
2445   tiny data area pointer.
2446 ENUM
2447   BFD_RELOC_V850_TDA_7_8_OFFSET
2448 ENUMDOC
2449   This is an 8bit offset (of which only 7 bits are used) from the tiny
2450   data area pointer.
2451 ENUM
2452   BFD_RELOC_V850_TDA_7_7_OFFSET
2453 ENUMDOC
2454   This is a 7 bit offset from the tiny data area pointer.
2455 ENUM
2456   BFD_RELOC_V850_TDA_16_16_OFFSET
2457 ENUMDOC
2458   This is a 16 bit offset from the tiny data area pointer.
2459 COMMENT
2460 ENUM
2461   BFD_RELOC_V850_TDA_4_5_OFFSET
2462 ENUMDOC
2463   This is a 5 bit offset (of which only 4 bits are used) from the tiny
2464   data area pointer.
2465 ENUM
2466   BFD_RELOC_V850_TDA_4_4_OFFSET
2467 ENUMDOC
2468   This is a 4 bit offset from the tiny data area pointer.
2469 ENUM
2470   BFD_RELOC_V850_SDA_16_16_SPLIT_OFFSET
2471 ENUMDOC
2472   This is a 16 bit offset from the short data area pointer, with the
2473   bits placed non-contigously in the instruction.
2474 ENUM
2475   BFD_RELOC_V850_ZDA_16_16_SPLIT_OFFSET
2476 ENUMDOC
2477   This is a 16 bit offset from the zero data area pointer, with the
2478   bits placed non-contigously in the instruction.
2479 ENUM
2480   BFD_RELOC_V850_CALLT_6_7_OFFSET
2481 ENUMDOC
2482   This is a 6 bit offset from the call table base pointer.
2483 ENUM
2484   BFD_RELOC_V850_CALLT_16_16_OFFSET
2485 ENUMDOC
2486   This is a 16 bit offset from the call table base pointer.
2487 COMMENT
2488
2489 ENUM
2490   BFD_RELOC_MN10300_32_PCREL
2491 ENUMDOC
2492   This is a 32bit pcrel reloc for the mn10300, offset by two bytes in the
2493   instruction.
2494 ENUM
2495   BFD_RELOC_MN10300_16_PCREL
2496 ENUMDOC
2497   This is a 16bit pcrel reloc for the mn10300, offset by two bytes in the
2498   instruction.
2499
2500 ENUM
2501   BFD_RELOC_TIC30_LDP
2502 ENUMDOC
2503   This is a 8bit DP reloc for the tms320c30, where the most
2504   significant 8 bits of a 24 bit word are placed into the least
2505   significant 8 bits of the opcode.
2506
2507 ENUM
2508   BFD_RELOC_FR30_48
2509 ENUMDOC
2510   This is a 48 bit reloc for the FR30 that stores 32 bits.
2511 ENUM
2512   BFD_RELOC_FR30_20
2513 ENUMDOC
2514   This is a 32 bit reloc for the FR30 that stores 20 bits split up into
2515   two sections.
2516 ENUM
2517   BFD_RELOC_FR30_6_IN_4
2518 ENUMDOC
2519   This is a 16 bit reloc for the FR30 that stores a 6 bit word offset in
2520   4 bits.
2521 ENUM
2522   BFD_RELOC_FR30_8_IN_8
2523 ENUMDOC
2524   This is a 16 bit reloc for the FR30 that stores an 8 bit byte offset
2525   into 8 bits.
2526 ENUM
2527   BFD_RELOC_FR30_9_IN_8
2528 ENUMDOC
2529   This is a 16 bit reloc for the FR30 that stores a 9 bit short offset
2530   into 8 bits.
2531 ENUM
2532   BFD_RELOC_FR30_10_IN_8
2533 ENUMDOC
2534   This is a 16 bit reloc for the FR30 that stores a 10 bit word offset
2535   into 8 bits.
2536 ENUM
2537   BFD_RELOC_FR30_9_PCREL
2538 ENUMDOC
2539   This is a 16 bit reloc for the FR30 that stores a 9 bit pc relative
2540   short offset into 8 bits.
2541 ENUM
2542   BFD_RELOC_FR30_12_PCREL
2543 ENUMDOC
2544   This is a 16 bit reloc for the FR30 that stores a 12 bit pc relative
2545   short offset into 11 bits.
2546
2547 ENUM
2548   BFD_RELOC_MCORE_PCREL_IMM8BY4
2549 ENUMX
2550   BFD_RELOC_MCORE_PCREL_IMM11BY2
2551 ENUMX
2552   BFD_RELOC_MCORE_PCREL_IMM4BY2
2553 ENUMX
2554   BFD_RELOC_MCORE_PCREL_32
2555 ENUMX
2556   BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2
2557 ENUMX
2558   BFD_RELOC_MCORE_RVA
2559 ENUMDOC
2560   Motorola Mcore relocations.
2561
2562 ENUM
2563   BFD_RELOC_VTABLE_INHERIT
2564 ENUMX
2565   BFD_RELOC_VTABLE_ENTRY
2566 ENUMDOC
2567   These two relocations are used by the linker to determine which of
2568   the entries in a C++ virtual function table are actually used.  When
2569   the --gc-sections option is given, the linker will zero out the entries
2570   that are not used, so that the code for those functions need not be
2571   included in the output.
2572
2573   VTABLE_INHERIT is a zero-space relocation used to describe to the
2574   linker the inheritence tree of a C++ virtual function table.  The
2575   relocation's symbol should be the parent class' vtable, and the
2576   relocation should be located at the child vtable.
2577
2578   VTABLE_ENTRY is a zero-space relocation that describes the use of a
2579   virtual function table entry.  The reloc's symbol should refer to the
2580   table of the class mentioned in the code.  Off of that base, an offset
2581   describes the entry that is being used.  For Rela hosts, this offset
2582   is stored in the reloc's addend.  For Rel hosts, we are forced to put
2583   this offset in the reloc's section offset.
2584
2585 ENDSENUM
2586   BFD_RELOC_UNUSED
2587 CODE_FRAGMENT
2588 .
2589 .typedef enum bfd_reloc_code_real bfd_reloc_code_real_type;
2590 */
2591
2592
2593 /*
2594 FUNCTION
2595         bfd_reloc_type_lookup
2596
2597 SYNOPSIS
2598         reloc_howto_type *
2599         bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
2600
2601 DESCRIPTION
2602         Return a pointer to a howto structure which, when
2603         invoked, will perform the relocation @var{code} on data from the
2604         architecture noted.
2605
2606 */
2607
2608
2609 reloc_howto_type *
2610 bfd_reloc_type_lookup (abfd, code)
2611      bfd *abfd;
2612      bfd_reloc_code_real_type code;
2613 {
2614   return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
2615 }
2616
2617 static reloc_howto_type bfd_howto_32 =
2618 HOWTO (0, 00, 2, 32, false, 0, complain_overflow_bitfield, 0, "VRT32", false, 0xffffffff, 0xffffffff, true);
2619
2620
2621 /*
2622 INTERNAL_FUNCTION
2623         bfd_default_reloc_type_lookup
2624
2625 SYNOPSIS
2626         reloc_howto_type *bfd_default_reloc_type_lookup
2627         (bfd *abfd, bfd_reloc_code_real_type  code);
2628
2629 DESCRIPTION
2630         Provides a default relocation lookup routine for any architecture.
2631
2632
2633 */
2634
2635 reloc_howto_type *
2636 bfd_default_reloc_type_lookup (abfd, code)
2637      bfd *abfd;
2638      bfd_reloc_code_real_type code;
2639 {
2640   switch (code)
2641     {
2642     case BFD_RELOC_CTOR:
2643       /* The type of reloc used in a ctor, which will be as wide as the
2644          address - so either a 64, 32, or 16 bitter.  */
2645       switch (bfd_get_arch_info (abfd)->bits_per_address)
2646         {
2647         case 64:
2648           BFD_FAIL ();
2649         case 32:
2650           return &bfd_howto_32;
2651         case 16:
2652           BFD_FAIL ();
2653         default:
2654           BFD_FAIL ();
2655         }
2656     default:
2657       BFD_FAIL ();
2658     }
2659   return (reloc_howto_type *) NULL;
2660 }
2661
2662 /*
2663 FUNCTION
2664         bfd_get_reloc_code_name
2665
2666 SYNOPSIS
2667         const char *bfd_get_reloc_code_name (bfd_reloc_code_real_type code);
2668
2669 DESCRIPTION
2670         Provides a printable name for the supplied relocation code.
2671         Useful mainly for printing error messages.
2672 */
2673
2674 const char *
2675 bfd_get_reloc_code_name (code)
2676      bfd_reloc_code_real_type code;
2677 {
2678   if (code > BFD_RELOC_UNUSED)
2679     return 0;
2680   return bfd_reloc_code_real_names[(int)code];
2681 }
2682
2683 /*
2684 INTERNAL_FUNCTION
2685         bfd_generic_relax_section
2686
2687 SYNOPSIS
2688         boolean bfd_generic_relax_section
2689          (bfd *abfd,
2690           asection *section,
2691           struct bfd_link_info *,
2692           boolean *);
2693
2694 DESCRIPTION
2695         Provides default handling for relaxing for back ends which
2696         don't do relaxing -- i.e., does nothing.
2697 */
2698
2699 /*ARGSUSED*/
2700 boolean
2701 bfd_generic_relax_section (abfd, section, link_info, again)
2702      bfd *abfd;
2703      asection *section;
2704      struct bfd_link_info *link_info;
2705      boolean *again;
2706 {
2707   *again = false;
2708   return true;
2709 }
2710
2711 /*
2712 INTERNAL_FUNCTION
2713         bfd_generic_gc_sections
2714
2715 SYNOPSIS
2716         boolean bfd_generic_gc_sections
2717          (bfd *, struct bfd_link_info *);
2718
2719 DESCRIPTION
2720         Provides default handling for relaxing for back ends which
2721         don't do section gc -- i.e., does nothing.
2722 */
2723
2724 /*ARGSUSED*/
2725 boolean
2726 bfd_generic_gc_sections (abfd, link_info)
2727      bfd *abfd;
2728      struct bfd_link_info *link_info;
2729 {
2730   return true;
2731 }
2732
2733 /*
2734 INTERNAL_FUNCTION
2735         bfd_generic_get_relocated_section_contents
2736
2737 SYNOPSIS
2738         bfd_byte *
2739            bfd_generic_get_relocated_section_contents (bfd *abfd,
2740              struct bfd_link_info *link_info,
2741              struct bfd_link_order *link_order,
2742              bfd_byte *data,
2743              boolean relocateable,
2744              asymbol **symbols);
2745
2746 DESCRIPTION
2747         Provides default handling of relocation effort for back ends
2748         which can't be bothered to do it efficiently.
2749
2750 */
2751
2752 bfd_byte *
2753 bfd_generic_get_relocated_section_contents (abfd, link_info, link_order, data,
2754                                             relocateable, symbols)
2755      bfd *abfd;
2756      struct bfd_link_info *link_info;
2757      struct bfd_link_order *link_order;
2758      bfd_byte *data;
2759      boolean relocateable;
2760      asymbol **symbols;
2761 {
2762   /* Get enough memory to hold the stuff */
2763   bfd *input_bfd = link_order->u.indirect.section->owner;
2764   asection *input_section = link_order->u.indirect.section;
2765
2766   long reloc_size = bfd_get_reloc_upper_bound (input_bfd, input_section);
2767   arelent **reloc_vector = NULL;
2768   long reloc_count;
2769
2770   if (reloc_size < 0)
2771     goto error_return;
2772
2773   reloc_vector = (arelent **) bfd_malloc ((size_t) reloc_size);
2774   if (reloc_vector == NULL && reloc_size != 0)
2775     goto error_return;
2776
2777   /* read in the section */
2778   if (!bfd_get_section_contents (input_bfd,
2779                                  input_section,
2780                                  (PTR) data,
2781                                  0,
2782                                  input_section->_raw_size))
2783     goto error_return;
2784
2785   /* We're not relaxing the section, so just copy the size info */
2786   input_section->_cooked_size = input_section->_raw_size;
2787   input_section->reloc_done = true;
2788
2789   reloc_count = bfd_canonicalize_reloc (input_bfd,
2790                                         input_section,
2791                                         reloc_vector,
2792                                         symbols);
2793   if (reloc_count < 0)
2794     goto error_return;
2795
2796   if (reloc_count > 0)
2797     {
2798       arelent **parent;
2799       for (parent = reloc_vector; *parent != (arelent *) NULL;
2800            parent++)
2801         {
2802           char *error_message = (char *) NULL;
2803           bfd_reloc_status_type r =
2804             bfd_perform_relocation (input_bfd,
2805                                     *parent,
2806                                     (PTR) data,
2807                                     input_section,
2808                                     relocateable ? abfd : (bfd *) NULL,
2809                                     &error_message);
2810
2811           if (relocateable)
2812             {
2813               asection *os = input_section->output_section;
2814
2815               /* A partial link, so keep the relocs */
2816               os->orelocation[os->reloc_count] = *parent;
2817               os->reloc_count++;
2818             }
2819
2820           if (r != bfd_reloc_ok)
2821             {
2822               switch (r)
2823                 {
2824                 case bfd_reloc_undefined:
2825                   if (!((*link_info->callbacks->undefined_symbol)
2826                         (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
2827                          input_bfd, input_section, (*parent)->address)))
2828                     goto error_return;
2829                   break;
2830                 case bfd_reloc_dangerous:
2831                   BFD_ASSERT (error_message != (char *) NULL);
2832                   if (!((*link_info->callbacks->reloc_dangerous)
2833                         (link_info, error_message, input_bfd, input_section,
2834                          (*parent)->address)))
2835                     goto error_return;
2836                   break;
2837                 case bfd_reloc_overflow:
2838                   if (!((*link_info->callbacks->reloc_overflow)
2839                         (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
2840                          (*parent)->howto->name, (*parent)->addend,
2841                          input_bfd, input_section, (*parent)->address)))
2842                     goto error_return;
2843                   break;
2844                 case bfd_reloc_outofrange:
2845                 default:
2846                   abort ();
2847                   break;
2848                 }
2849
2850             }
2851         }
2852     }
2853   if (reloc_vector != NULL)
2854     free (reloc_vector);
2855   return data;
2856
2857 error_return:
2858   if (reloc_vector != NULL)
2859     free (reloc_vector);
2860   return NULL;
2861 }