bfd/reloc.c

   1 /* BFD support for handling relocation entries.
   2    Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
   3    Written by Cygnus Support.
   4
   5 This file is part of BFD, the Binary File Descriptor library.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 /*
  22 SECTION
  23         Relocations
  24
  25         BFD maintains relocations in much the same was as it maintains
  26         symbols; they are left alone until required, then read in
  27         en-mass and traslated into an internal form. There is a common
  28         routine <<bfd_perform_relocation>> which acts upon the
  29         canonical form to to the actual fixup.
  30
  31         Note that relocations are maintained on a per section basis,
  32         whilst symbols are maintained on a per BFD basis.
  33
  34         All a back end has to do to fit the BFD interface is to create
  35         as many <<struct reloc_cache_entry>> as there are relocations
  36         in a particular section, and fill in the right bits:
  37
  38 @menu
  39 @* typedef arelent::
  40 @* howto manager::
  41 @end menu
  42
  43 */
  44 #include "bfd.h"
  45 #include "sysdep.h"
  46 #include "libbfd.h"
  47 #include "seclet.h"
  48 /*
  49 DOCDD
  50 INODE
  51         typedef arelent, howto manager, Relocations, Relocations
  52
  53 SUBSECTION
  54         typedef arelent
  55
  56         This is the structure of a relocation entry:
  57
  58 CODE_FRAGMENT
  59 .
  60 .typedef enum bfd_reloc_status
  61 .{
  62 .       {* No errors detected *}
  63 .  bfd_reloc_ok,
  64 .
  65 .       {* The relocation was performed, but there was an overflow. *}
  66 .  bfd_reloc_overflow,
  67 .
  68 .       {* The address to relocate was not within the section supplied. *}
  69 .  bfd_reloc_outofrange,
  70 .
  71 .       {* Used by special functions *}
  72 .  bfd_reloc_continue,
  73 .
  74 .       {* Unused *}
  75 .  bfd_reloc_notsupported,
  76 .
  77 .       {* Unsupported relocation size requested. *}
  78 .  bfd_reloc_other,
  79 .
  80 .       {* The symbol to relocate against was undefined. *}
  81 .  bfd_reloc_undefined,
  82 .
  83 .       {* The relocation was performed, but may not be ok - presently
  84 .          generated only when linking i960 coff files with i960 b.out
  85 .          symbols. *}
  86 .  bfd_reloc_dangerous
  87 . }
  88 . bfd_reloc_status_type;
  89 .
  90 .
  91 .typedef struct reloc_cache_entry
  92 .{
  93 .       {* A pointer into the canonical table of pointers  *}
  94 .  struct symbol_cache_entry **sym_ptr_ptr;
  95 .
  96 .       {* offset in section *}
  97 .  bfd_size_type address;
  98 .
  99 .       {* addend for relocation value *}
 100 .  bfd_vma addend;
 101 .
 102 .       {* Pointer to how to perform the required relocation *}
 103 .  CONST struct reloc_howto_struct *howto;
 104 .
 105 .} arelent;
 106
 107 */
 108
 109 /*
 110 DESCRIPTION
 111
 112         Here is a description of each of the fields within a relent:
 113
 114         o sym_ptr_ptr
 115
 116         The symbol table pointer points to a pointer to the symbol
 117         associated with the relocation request. This would naturally
 118         be the pointer into the table returned by the back end's
 119         get_symtab action. @xref{Symbols}. The symbol is referenced
 120         through a pointer to a pointer so that tools like the linker
 121         can fix up all the symbols of the same name by modifying only
 122         one pointer. The relocation routine looks in the symbol and
 123         uses the base of the section the symbol is attached to and the
 124         value of the symbol as the initial relocation offset. If the
 125         symbol pointer is zero, then the section provided is looked up.
 126
 127         o address
 128
 129         The address field gives the offset in bytes from the base of
 130         the section data which owns the relocation record to the first
 131         byte of relocatable information. The actual data relocated
 132         will be relative to this point - for example, a relocation
 133         type which modifies the bottom two bytes of a four byte word
 134         would not touch the first byte pointed to in a big endian
 135         world.
 136
 137         o addend
 138
 139         The addend is a value provided by the back end to be added (!)
 140         to the relocation offset. Its interpretation is dependent upon
 141         the howto. For example, on the 68k the code:
 142
 143
 144 |        char foo[];
 145 |        main()
 146 |                {
 147 |                return foo[0x12345678];
 148 |                }
 149
 150         Could be compiled into:
 151
 152 |        linkw fp,#-4
 153 |        moveb @@#12345678,d0
 154 |        extbl d0
 155 |        unlk fp
 156 |        rts
 157
 158
 159         This could create a reloc pointing to foo, but leave the
 160         offset in the data (something like)
 161
 162
 163 |RELOCATION RECORDS FOR [.text]:
 164 |offset   type      value
 165 |00000006 32        _foo
 166 |
 167 |00000000 4e56 fffc          ; linkw fp,#-4
 168 |00000004 1039 1234 5678     ; moveb @@#12345678,d0
 169 |0000000a 49c0               ; extbl d0
 170 |0000000c 4e5e               ; unlk fp
 171 |0000000e 4e75               ; rts
 172
 173
 174         Using coff and an 88k, some instructions don't have enough
 175         space in them to represent the full address range, and
 176         pointers have to be loaded in two parts. So you'd get something like:
 177
 178
 179 |        or.u     r13,r0,hi16(_foo+0x12345678)
 180 |        ld.b     r2,r13,lo16(_foo+0x12345678)
 181 |        jmp      r1
 182
 183
 184         This should create two relocs, both pointing to _foo, and with
 185         0x12340000 in their addend field. The data would consist of:
 186
 187
 188 |RELOCATION RECORDS FOR [.text]:
 189 |offset   type      value
 190 |00000002 HVRT16    _foo+0x12340000
 191 |00000006 LVRT16    _foo+0x12340000
 192
 193 |00000000 5da05678           ; or.u r13,r0,0x5678
 194 |00000004 1c4d5678           ; ld.b r2,r13,0x5678
 195 |00000008 f400c001           ; jmp r1
 196
 197
 198         The relocation routine digs out the value from the data, adds
 199         it to the addend to get the original offset and then adds the
 200         value of _foo. Note that all 32 bits have to be kept around
 201         somewhere, to cope with carry from bit 15 to bit 16.
 202
 203         One further example is the sparc and the a.out format. The
 204         sparc has a similar problem to the 88k, in that some
 205         instructions don't have room for an entire offset, but on the
 206         sparc the parts are created odd sized lumps. The designers of
 207         the a.out format chose not to use the data within the section
 208         for storing part of the offset; all the offset is kept within
 209         the reloc. Any thing in the data should be ignored.
 210
 211 |        save %sp,-112,%sp
 212 |        sethi %hi(_foo+0x12345678),%g2
 213 |        ldsb [%g2+%lo(_foo+0x12345678)],%i0
 214 |        ret
 215 |        restore
 216
 217         Both relocs contains a pointer to foo, and the offsets would
 218         contain junk.
 219
 220
 221 |RELOCATION RECORDS FOR [.text]:
 222 |offset   type      value
 223 |00000004 HI22      _foo+0x12345678
 224 |00000008 LO10      _foo+0x12345678
 225
 226 |00000000 9de3bf90     ; save %sp,-112,%sp
 227 |00000004 05000000     ; sethi %hi(_foo+0),%g2
 228 |00000008 f048a000     ; ldsb [%g2+%lo(_foo+0)],%i0
 229 |0000000c 81c7e008     ; ret
 230 |00000010 81e80000     ; restore
 231
 232
 233         o howto
 234
 235         The howto field can be imagined as a
 236         relocation instruction. It is a pointer to a struct which
 237         contains information on what to do with all the other
 238         information in the reloc record and data section. A back end
 239         would normally have a relocation instruction set and turn
 240         relocations into pointers to the correct structure on input -
 241         but it would be possible to create each howto field on demand.
 242
 243 */
 244
 245
 246 /*
 247 SUBSUBSECTION
 248         <<reloc_howto_type>>
 249
 250         The <<reloc_howto_type>> is a structure which contains all the
 251         information that BFD needs to know to tie up a back end's data.
 252
 253 CODE_FRAGMENT
 254 .struct symbol_cache_entry;             {* Forward declaration *}
 255 .
 256 .typedef CONST struct reloc_howto_struct
 257 .{
 258 .       {*  The type field has mainly a documetary use - the back end can
 259 .           to what it wants with it, though the normally the back end's
 260 .           external idea of what a reloc number would be would be stored
 261 .           in this field. For example, the a PC relative word relocation
 262 .           in a coff environment would have the type 023 - because that's
 263 .           what the outside world calls a R_PCRWORD reloc. *}
 264 .  unsigned int type;
 265 .
 266 .       {*  The value the final relocation is shifted right by. This drops
 267 .           unwanted data from the relocation.  *}
 268 .  unsigned int rightshift;
 269 .
 270 .       {*  The size of the item to be relocated - 0, is one byte, 1 is 2
 271 .           bytes, 2 is four bytes.  A negative value indicates that the
 272 .           result is to be subtracted from the data.  *}
 273 .  int size;
 274 .
 275 .       {*  Now obsolete?  But m68k-coff still uses it... *}
 276 .  unsigned int bitsize;
 277 .
 278 .       {*  Notes that the relocation is relative to the location in the
 279 .           data section of the addend. The relocation function will
 280 .           subtract from the relocation value the address of the location
 281 .           being relocated. *}
 282 .  boolean pc_relative;
 283 .
 284 .  unsigned int bitpos;
 285 .
 286 .       {*  Now obsolete *}
 287 .  boolean absolute;
 288 .
 289 .       {* Causes the relocation routine to return an error if overflow
 290 .          is detected when relocating. *}
 291 .  boolean complain_on_overflow;
 292 .
 293 .       {* If this field is non null, then the supplied function is
 294 .          called rather than the normal function. This allows really
 295 .          strange relocation methods to be accomodated (e.g., i960 callj
 296 .          instructions). *}
 297 .  bfd_reloc_status_type (*special_function)
 298 .                                   PARAMS ((bfd *abfd,
 299 .                                            arelent *reloc_entry,
 300 .                                            struct symbol_cache_entry *symbol,
 301 .                                            PTR data,
 302 .                                            asection *input_section,
 303 .                                            bfd *output_bfd));
 304 .
 305 .       {* The textual name of the relocation type. *}
 306 .  char *name;
 307 .
 308 .       {* When performing a partial link, some formats must modify the
 309 .          relocations rather than the data - this flag signals this.*}
 310 .  boolean partial_inplace;
 311 .
 312 .       {* The src_mask is used to select what parts of the read in data
 313 .          are to be used in the relocation sum.  E.g., if this was an 8 bit
 314 .          bit of data which we read and relocated, this would be
 315 .          0x000000ff. When we have relocs which have an addend, such as
 316 .          sun4 extended relocs, the value in the offset part of a
 317 .          relocating field is garbage so we never use it. In this case
 318 .          the mask would be 0x00000000. *}
 319 .  bfd_vma src_mask;
 320 .
 321 .       {* The dst_mask is what parts of the instruction are replaced
 322 .          into the instruction. In most cases src_mask == dst_mask,
 323 .          except in the above special case, where dst_mask would be
 324 .          0x000000ff, and src_mask would be 0x00000000.   *}
 325 .  bfd_vma dst_mask;
 326 .
 327 .       {* When some formats create PC relative instructions, they leave
 328 .          the value of the pc of the place being relocated in the offset
 329 .          slot of the instruction, so that a PC relative relocation can
 330 .          be made just by adding in an ordinary offset (e.g., sun3 a.out).
 331 .          Some formats leave the displacement part of an instruction
 332 .          empty (e.g., m88k bcs), this flag signals the fact.*}
 333 .  boolean pcrel_offset;
 334 .
 335 .} reloc_howto_type;
 336
 337 */
 338
 339 /*
 340 FUNCTION
 341         the HOWTO macro
 342
 343 DESCRIPTION
 344         The HOWTO define is horrible and will go away.
 345
 346
 347 .#define HOWTO(C, R,S,B, P, BI, ABS, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
 348 .  {(unsigned)C,R,S,B, P, BI, ABS,O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
 349
 350 DESCRIPTION
 351         And will be replaced with the totally magic way. But for the
 352         moment, we are compatible, so do it this way..
 353
 354
 355 .#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,false,false,FUNCTION, NAME,false,0,0,IN)
 356 .
 357 DESCRIPTION
 358         Helper routine to turn a symbol into a relocation value.
 359
 360 .#define HOWTO_PREPARE(relocation, symbol)      \
 361 .  {                                            \
 362 .  if (symbol != (asymbol *)NULL) {             \
 363 .    if (bfd_is_com_section (symbol->section)) { \
 364 .      relocation = 0;                          \
 365 .    }                                          \
 366 .    else {                                     \
 367 .      relocation = symbol->value;              \
 368 .    }                                          \
 369 .  }                                            \
 370 .}
 371
 372 */
 373
 374 /*
 375 TYPEDEF
 376         reloc_chain
 377
 378 DESCRIPTION
 379
 380         How relocs are tied together
 381
 382 .typedef unsigned char bfd_byte;
 383 .
 384 .typedef struct relent_chain {
 385 .  arelent relent;
 386 .  struct   relent_chain *next;
 387 .} arelent_chain;
 388
 389 */
 390
 391
 392
 393 /*
 394 FUNCTION
 395         bfd_perform_relocation
 396
 397 SYNOPSIS
 398         bfd_reloc_status_type
 399                 bfd_perform_relocation
 400                         (bfd * abfd,
 401                         arelent *reloc_entry,
 402                         PTR data,
 403                         asection *input_section,
 404                         bfd *output_bfd);
 405
 406 DESCRIPTION
 407         If an output_bfd is supplied to this function the generated
 408         image will be relocatable, the relocations are copied to the
 409         output file after they have been changed to reflect the new
 410         state of the world. There are two ways of reflecting the
 411         results of partial linkage in an output file; by modifying the
 412         output data in place, and by modifying the relocation record.
 413         Some native formats (e.g., basic a.out and basic coff) have no
 414         way of specifying an addend in the relocation type, so the
 415         addend has to go in the output data.  This is no big deal
 416         since in these formats the output data slot will always be big
 417         enough for the addend. Complex reloc types with addends were
 418         invented to solve just this problem.
 419
 420 */
 421
 422
 423 bfd_reloc_status_type
 424 DEFUN(bfd_perform_relocation,(abfd,
 425                               reloc_entry,
 426                               data,
 427                               input_section,
 428                               output_bfd),
 429       bfd *abfd AND
 430       arelent *reloc_entry AND
 431       PTR data AND
 432       asection *input_section AND
 433       bfd *output_bfd)
 434 {
 435   bfd_vma relocation;
 436   bfd_reloc_status_type flag = bfd_reloc_ok;
 437   bfd_size_type addr = reloc_entry->address ;
 438   bfd_vma output_base = 0;
 439   reloc_howto_type *howto = reloc_entry->howto;
 440   asection *reloc_target_output_section ;
 441
 442   asymbol *symbol;
 443
 444   symbol = *( reloc_entry->sym_ptr_ptr);
 445   if ((symbol->section == &bfd_abs_section)
 446       && output_bfd != (bfd *)NULL)
 447   {
 448     reloc_entry->address += input_section->output_offset;
 449
 450     return bfd_reloc_ok;
 451
 452   }
 453
 454   if ((symbol->section == &bfd_und_section) && output_bfd == (bfd *)NULL) {
 455     flag = bfd_reloc_undefined;
 456   }
 457
 458   if (howto->special_function) {
 459     bfd_reloc_status_type cont;
 460     cont = howto->special_function(abfd,
 461                                    reloc_entry,
 462                                    symbol,
 463                                    data,
 464                                    input_section,
 465                                    output_bfd);
 466     if (cont != bfd_reloc_continue) return cont;
 467   }
 468
 469   /*
 470     Work out which section the relocation is targetted at and the
 471     initial relocation command value.
 472     */
 473
 474
 475   if (bfd_is_com_section (symbol->section)) {
 476     relocation = 0;
 477   }
 478   else {
 479     relocation = symbol->value;
 480   }
 481
 482
 483   reloc_target_output_section = symbol->section->output_section;
 484
 485   if (output_bfd && howto->partial_inplace==false) {
 486     output_base = 0;
 487   }
 488   else {
 489     output_base = reloc_target_output_section->vma;
 490
 491   }
 492
 493   relocation += output_base + symbol->section->output_offset;
 494
 495   relocation += reloc_entry->addend;
 496
 497   if(reloc_entry->address > input_section->_cooked_size)
 498   {
 499     return bfd_reloc_outofrange;
 500   }
 501
 502
 503   if (howto->pc_relative == true)
 504   {
 505     /*
 506       Anything which started out as pc relative should end up that
 507       way too.
 508
 509       There are two ways we can see a pcrel instruction. Sometimes
 510       the pcrel displacement has been partially calculated, it
 511       includes the distance from the start of the section to the
 512       instruction in it (e.g., sun3), and sometimes the field is
 513       totally blank - e.g., m88kbcs.
 514       */
 515
 516
 517     relocation -=
 518      input_section->output_section->vma + input_section->output_offset;
 519
 520     if (howto->pcrel_offset == true) {
 521       relocation -= reloc_entry->address;
 522     }
 523   }
 524
 525   if (output_bfd!= (bfd *)NULL)
 526   {
 527     if ( howto->partial_inplace == false)
 528     {
 529       /*
 530         This is a partial relocation, and we want to apply the relocation
 531         to the reloc entry rather than the raw data. Modify the reloc
 532         inplace to reflect what we now know.
 533         */
 534       reloc_entry->addend = relocation  ;
 535       reloc_entry->address +=  input_section->output_offset;
 536       return flag;
 537     }
 538     else
 539     {
 540       /* This is a partial relocation, but inplace, so modify the
 541          reloc record a bit.
 542
 543          If we've relocated with a symbol with a section, change
 544          into a ref to  the section belonging to the symbol
 545          */
 546
 547       reloc_entry->address += input_section->output_offset;
 548
 549       if (abfd->xvec->flavour == bfd_target_coff_flavour)
 550       {
 551         relocation -= reloc_entry->addend;
 552         reloc_entry->addend = 0;
 553       }
 554       else
 555       {
 556         reloc_entry->addend = relocation  ;
 557       }
 558     }
 559   }
 560   else
 561   {
 562     reloc_entry->addend = 0;
 563   }
 564
 565
 566   if (howto->complain_on_overflow && howto->pc_relative)
 567     {
 568       /* We can detect overflow safely here */
 569
 570       bfd_signed_vma reloc_max = (1 << (howto->bitsize - 1))-1;
 571       bfd_signed_vma reloc_min = ~(reloc_max);
 572
 573       if ((bfd_signed_vma) relocation > reloc_max
 574           || (bfd_signed_vma) relocation < reloc_min)
 575         {
 576           flag = bfd_reloc_overflow;
 577         }
 578     }
 579
 580   /*
 581     Either we are relocating all the way, or we don't want to apply
 582     the relocation to the reloc entry (probably because there isn't
 583     any room in the output format to describe addends to relocs)
 584     */
 585   relocation >>= howto->rightshift;
 586
 587   /* Shift everything up to where it's going to be used */
 588
 589   relocation <<= howto->bitpos;
 590
 591   /* Wait for the day when all have the mask in them */
 592
 593   /* What we do:
 594      i instruction to be left alone
 595      o offset within instruction
 596      r relocation offset to apply
 597      S src mask
 598      D dst mask
 599      N ~dst mask
 600      A part 1
 601      B part 2
 602      R result
 603
 604      Do this:
 605      i i i i i o o o o o        from bfd_get<size>
 606      and           S S S S S    to get the size offset we want
 607      +   r r r r r r r r r r  to get the final value to place
 608      and           D D D D D  to chop to right size
 609      -----------------------
 610      A A A A A
 611      And this:
 612      ...   i i i i i o o o o o  from bfd_get<size>
 613      and   N N N N N            get instruction
 614      -----------------------
 615      ...   B B B B B
 616
 617      And then:
 618      B B B B B
 619      or              A A A A A
 620      -----------------------
 621      R R R R R R R R R R        put into bfd_put<size>
 622      */
 623
 624 #define DOIT(x) \
 625   x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) +  relocation) & howto->dst_mask))
 626
 627    switch (howto->size)
 628      {
 629      case 0:
 630        {
 631          char x = bfd_get_8(abfd, (char *)data + addr);
 632          DOIT(x);
 633          bfd_put_8(abfd,x, (unsigned char *) data + addr);
 634        }
 635        break;
 636
 637      case 1:
 638        if (relocation)
 639          {
 640            short x = bfd_get_16(abfd, (bfd_byte *)data + addr);
 641            DOIT(x);
 642            bfd_put_16(abfd, x,   (unsigned char *)data + addr);
 643          }
 644        break;
 645      case 2:
 646        if (relocation)
 647          {
 648            long  x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
 649            DOIT (x);
 650            bfd_put_32 (abfd, x, (bfd_byte *)data + addr);
 651          }
 652        break;
 653      case -2:
 654        {
 655          long  x = bfd_get_32(abfd, (bfd_byte *) data + addr);
 656          relocation = -relocation;
 657          DOIT(x);
 658          bfd_put_32(abfd,x,    (bfd_byte *)data + addr);
 659        }
 660        break;
 661
 662      case 3:
 663
 664        /* Do nothing */
 665        break;
 666      default:
 667        return bfd_reloc_other;
 668      }
 669
 670   return flag;
 671 }
 672
 673
 674
 675 /*
 676 DOCDD
 677 INODE
 678         howto manager,  , typedef arelent, Relocations
 679
 680 SECTION
 681         The howto manager
 682
 683         When an application wants to create a relocation, but doesn't
 684         know what the target machine might call it, it can find out by
 685         using this bit of code.
 686
 687 */
 688
 689 /*
 690 TYPEDEF
 691         bfd_reloc_code_type
 692
 693 DESCRIPTION
 694         The insides of a reloc code
 695
 696 CODE_FRAGMENT
 697 .
 698 .typedef enum bfd_reloc_code_real
 699 .
 700 .{
 701 .       {* 64 bits wide, simple reloc *}
 702 .  BFD_RELOC_64,
 703 .       {* 64 bits, PC-relative *}
 704 .  BFD_RELOC_64_PCREL,
 705 .
 706 .       {* 32 bits wide, simple reloc *}
 707 .  BFD_RELOC_32,
 708 .       {* 32 bits, PC-relative *}
 709 .  BFD_RELOC_32_PCREL,
 710 .
 711 .       {* 16 bits wide, simple reloc *}
 712 .  BFD_RELOC_16,
 713 .       {* 16 bits, PC-relative *}
 714 .  BFD_RELOC_16_PCREL,
 715 .
 716 .       {* 8 bits wide, simple *}
 717 .  BFD_RELOC_8,
 718 .       {* 8 bits wide, pc relative *}
 719 .  BFD_RELOC_8_PCREL,
 720 .       {* 8 bits wide, but used to form an address like 0xffnn *}
 721 .  BFD_RELOC_8_FFnn,
 722 .
 723 .       {* The type of reloc used to build a contructor table - at the
 724 .          moment probably a 32 bit wide abs address, but the cpu can
 725 .          choose. *}
 726 .
 727 .  BFD_RELOC_CTOR,
 728 .
 729 .       {* High 22 bits of 32-bit value; simple reloc.  *}
 730 .  BFD_RELOC_HI22,
 731 .       {* Low 10 bits.  *}
 732 .  BFD_RELOC_LO10,
 733 .
 734 .       {* Reloc types used for i960/b.out.  *}
 735 .  BFD_RELOC_24_PCREL,
 736 .  BFD_RELOC_I960_CALLJ,
 737 .
 738 .       {* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit
 739 .          word displacement, e.g. for SPARC) *}
 740 .  BFD_RELOC_32_PCREL_S2,
 741 .
 742 .  {* now for the sparc/elf codes *}
 743 .  BFD_RELOC_NONE,              {* actually used *}
 744 .  BFD_RELOC_SPARC_WDISP22,
 745 .  BFD_RELOC_SPARC22,
 746 .  BFD_RELOC_SPARC13,
 747 .  BFD_RELOC_SPARC_BASE13,
 748 .  BFD_RELOC_SPARC_GOT10,
 749 .  BFD_RELOC_SPARC_GOT13,
 750 .  BFD_RELOC_SPARC_GOT22,
 751 .  BFD_RELOC_SPARC_PC10,
 752 .  BFD_RELOC_SPARC_PC22,
 753 .  BFD_RELOC_SPARC_WPLT30,
 754 .  BFD_RELOC_SPARC_COPY,
 755 .  BFD_RELOC_SPARC_GLOB_DAT,
 756 .  BFD_RELOC_SPARC_JMP_SLOT,
 757 .  BFD_RELOC_SPARC_RELATIVE,
 758 .  BFD_RELOC_SPARC_UA32,
 759 .
 760 .  {* this one is a.out specific? *}
 761 .  BFD_RELOC_SPARC_BASE22,
 762 .
 763 .  {* start-sanitize-v9 *}
 764 .  BFD_RELOC_SPARC_WDISP19,
 765 .  BFD_RELOC_SPARC_10,
 766 .  BFD_RELOC_SPARC_11,
 767 .#define  BFD_RELOC_SPARC_64 BFD_RELOC_64
 768 .  BFD_RELOC_SPARC_OLO10,
 769 .  BFD_RELOC_SPARC_HH22,
 770 .  BFD_RELOC_SPARC_HM10,
 771 .  BFD_RELOC_SPARC_LM22,
 772 .  BFD_RELOC_SPARC_PC_HH22,
 773 .  BFD_RELOC_SPARC_PC_HM10,
 774 .  BFD_RELOC_SPARC_PC_LM22,
 775 .  BFD_RELOC_SPARC_WDISP16,
 776 .  BFD_RELOC_SPARC_GLOB_JMP,
 777 .  BFD_RELOC_SPARC_LO7,
 778 .  {* end-sanitize-v9 *}
 779 .       {* Bits 27..2 of the relocation address shifted right 2 bits;
 780 .         simple reloc otherwise.  *}
 781 .  BFD_RELOC_MIPS_JMP,
 782 .
 783 .       {* signed 16-bit pc-relative, shifted right 2 bits (e.g. for MIPS) *}
 784 .  BFD_RELOC_16_PCREL_S2,
 785 .
 786 .       {* High 16 bits of 32-bit value; simple reloc.  *}
 787 .  BFD_RELOC_HI16,
 788 .       {* High 16 bits of 32-bit value but the low 16 bits will be sign
 789 .          extended and added to form the final result.  If the low 16
 790 .          bits form a negative number, we need to add one to the high value
 791 .          to compensate for the borrow when the low bits are added.  *}
 792 .  BFD_RELOC_HI16_S,
 793 .       {* Low 16 bits.  *}
 794 .  BFD_RELOC_LO16,
 795 .
 796 .       {* 16 bit relocation relative to the global pointer.  *}
 797 .  BFD_RELOC_MIPS_GPREL,
 798 .
 799 .       {* These are, so far, specific to HPPA processors.  I'm not sure that
 800 .          some don't duplicate other reloc types, such as BFD_RELOC_32 and
 801 .          _32_PCREL.  Also, many more were in the list I got that don't
 802 .          fit in well in the model BFD uses, so I've omitted them for now.
 803 .          If we do make this reloc type get used for code that really does
 804 .          implement the funky reloc types, they'll have to be added to this
 805 .          list.   *}
 806 .  BFD_RELOC_HPPA_32,
 807 .  BFD_RELOC_HPPA_11,
 808 .  BFD_RELOC_HPPA_14,
 809 .  BFD_RELOC_HPPA_17,
 810 .  BFD_RELOC_HPPA_L21,
 811 .  BFD_RELOC_HPPA_R11,
 812 .  BFD_RELOC_HPPA_R14,
 813 .  BFD_RELOC_HPPA_R17,
 814 .  BFD_RELOC_HPPA_LS21,
 815 .  BFD_RELOC_HPPA_RS11,
 816 .  BFD_RELOC_HPPA_RS14,
 817 .  BFD_RELOC_HPPA_RS17,
 818 .  BFD_RELOC_HPPA_LD21,
 819 .  BFD_RELOC_HPPA_RD11,
 820 .  BFD_RELOC_HPPA_RD14,
 821 .  BFD_RELOC_HPPA_RD17,
 822 .  BFD_RELOC_HPPA_LR21,
 823 .  BFD_RELOC_HPPA_RR14,
 824 .  BFD_RELOC_HPPA_RR17,
 825 .  BFD_RELOC_HPPA_GOTOFF_11,
 826 .  BFD_RELOC_HPPA_GOTOFF_14,
 827 .  BFD_RELOC_HPPA_GOTOFF_L21,
 828 .  BFD_RELOC_HPPA_GOTOFF_R11,
 829 .  BFD_RELOC_HPPA_GOTOFF_R14,
 830 .  BFD_RELOC_HPPA_GOTOFF_LS21,
 831 .  BFD_RELOC_HPPA_GOTOFF_RS11,
 832 .  BFD_RELOC_HPPA_GOTOFF_RS14,
 833 .  BFD_RELOC_HPPA_GOTOFF_LD21,
 834 .  BFD_RELOC_HPPA_GOTOFF_RD11,
 835 .  BFD_RELOC_HPPA_GOTOFF_RD14,
 836 .  BFD_RELOC_HPPA_GOTOFF_LR21,
 837 .  BFD_RELOC_HPPA_GOTOFF_RR14,
 838 .  BFD_RELOC_HPPA_DLT_32,
 839 .  BFD_RELOC_HPPA_DLT_11,
 840 .  BFD_RELOC_HPPA_DLT_14,
 841 .  BFD_RELOC_HPPA_DLT_L21,
 842 .  BFD_RELOC_HPPA_DLT_R11,
 843 .  BFD_RELOC_HPPA_DLT_R14,
 844 .  BFD_RELOC_HPPA_ABS_CALL_11,
 845 .  BFD_RELOC_HPPA_ABS_CALL_14,
 846 .  BFD_RELOC_HPPA_ABS_CALL_17,
 847 .  BFD_RELOC_HPPA_ABS_CALL_L21,
 848 .  BFD_RELOC_HPPA_ABS_CALL_R11,
 849 .  BFD_RELOC_HPPA_ABS_CALL_R14,
 850 .  BFD_RELOC_HPPA_ABS_CALL_R17,
 851 .  BFD_RELOC_HPPA_ABS_CALL_LS21,
 852 .  BFD_RELOC_HPPA_ABS_CALL_RS11,
 853 .  BFD_RELOC_HPPA_ABS_CALL_RS14,
 854 .  BFD_RELOC_HPPA_ABS_CALL_RS17,
 855 .  BFD_RELOC_HPPA_ABS_CALL_LD21,
 856 .  BFD_RELOC_HPPA_ABS_CALL_RD11,
 857 .  BFD_RELOC_HPPA_ABS_CALL_RD14,
 858 .  BFD_RELOC_HPPA_ABS_CALL_RD17,
 859 .  BFD_RELOC_HPPA_ABS_CALL_LR21,
 860 .  BFD_RELOC_HPPA_ABS_CALL_RR14,
 861 .  BFD_RELOC_HPPA_ABS_CALL_RR17,
 862 .  BFD_RELOC_HPPA_PCREL_CALL_11,
 863 .  BFD_RELOC_HPPA_PCREL_CALL_12,
 864 .  BFD_RELOC_HPPA_PCREL_CALL_14,
 865 .  BFD_RELOC_HPPA_PCREL_CALL_17,
 866 .  BFD_RELOC_HPPA_PCREL_CALL_L21,
 867 .  BFD_RELOC_HPPA_PCREL_CALL_R11,
 868 .  BFD_RELOC_HPPA_PCREL_CALL_R14,
 869 .  BFD_RELOC_HPPA_PCREL_CALL_R17,
 870 .  BFD_RELOC_HPPA_PCREL_CALL_LS21,
 871 .  BFD_RELOC_HPPA_PCREL_CALL_RS11,
 872 .  BFD_RELOC_HPPA_PCREL_CALL_RS14,
 873 .  BFD_RELOC_HPPA_PCREL_CALL_RS17,
 874 .  BFD_RELOC_HPPA_PCREL_CALL_LD21,
 875 .  BFD_RELOC_HPPA_PCREL_CALL_RD11,
 876 .  BFD_RELOC_HPPA_PCREL_CALL_RD14,
 877 .  BFD_RELOC_HPPA_PCREL_CALL_RD17,
 878 .  BFD_RELOC_HPPA_PCREL_CALL_LR21,
 879 .  BFD_RELOC_HPPA_PCREL_CALL_RR14,
 880 .  BFD_RELOC_HPPA_PCREL_CALL_RR17,
 881 .  BFD_RELOC_HPPA_PLABEL_32,
 882 .  BFD_RELOC_HPPA_PLABEL_11,
 883 .  BFD_RELOC_HPPA_PLABEL_14,
 884 .  BFD_RELOC_HPPA_PLABEL_L21,
 885 .  BFD_RELOC_HPPA_PLABEL_R11,
 886 .  BFD_RELOC_HPPA_PLABEL_R14,
 887 .  BFD_RELOC_HPPA_UNWIND_ENTRY,
 888 .  BFD_RELOC_HPPA_UNWIND_ENTRIES,
 889 .
 890 .  {* this must be the highest numeric value *}
 891 .  BFD_RELOC_UNUSED
 892 . } bfd_reloc_code_real_type;
 893 */
 894
 895
 896
 897 /*
 898 SECTION
 899         bfd_reloc_type_lookup
 900
 901 SYNOPSIS
 902         CONST struct reloc_howto_struct *
 903         bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
 904
 905 DESCRIPTION
 906         This routine returns a pointer to a howto struct which when
 907         invoked, will perform the supplied relocation on data from the
 908         architecture noted.
 909
 910 */
 911
 912
 913 CONST struct reloc_howto_struct *
 914 DEFUN(bfd_reloc_type_lookup,(abfd, code),
 915       bfd *abfd AND
 916       bfd_reloc_code_real_type code)
 917 {
 918   return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
 919 }
 920
 921 static reloc_howto_type bfd_howto_32 =
 922  HOWTO(0, 00,2,32,false,0,false,true,0,"VRT32", false,0xffffffff,0xffffffff,true);
 923
 924
 925 /*
 926 INTERNAL_FUNCTION
 927         bfd_default_reloc_type_lookup
 928
 929 SYNOPSIS
 930         CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup
 931         (bfd *abfd AND
 932          bfd_reloc_code_real_type  code);
 933
 934 DESCRIPTION
 935         Provides a default relocation lookup routine for any architecture.
 936
 937
 938 */
 939
 940 CONST struct reloc_howto_struct *
 941 DEFUN(bfd_default_reloc_type_lookup, (abfd, code),
 942       bfd *abfd AND
 943       bfd_reloc_code_real_type code)
 944 {
 945   switch (code)
 946     {
 947     case BFD_RELOC_CTOR:
 948       /* The type of reloc used in a ctor, which will be as wide as the
 949          address - so either a 64, 32, or 16 bitter.. */
 950       switch (bfd_get_arch_info (abfd)->bits_per_address) {
 951       case 64:
 952         BFD_FAIL();
 953       case 32:
 954         return &bfd_howto_32;
 955       case 16:
 956         BFD_FAIL();
 957       default:
 958         BFD_FAIL();
 959       }
 960     default:
 961       BFD_FAIL();
 962     }
 963   return (CONST struct reloc_howto_struct *)NULL;
 964 }
 965
 966
 967 /*
 968 INTERNAL_FUNCTION
 969         bfd_generic_relax_section
 970
 971 SYNOPSIS
 972         boolean bfd_generic_relax_section
 973          (bfd *abfd,
 974           asection *section,
 975           asymbol **symbols);
 976
 977 DESCRIPTION
 978         Provides default handling for relaxing for back ends which
 979         don't do relaxing -- i.e., does nothing.
 980 */
 981
 982 boolean
 983 DEFUN(bfd_generic_relax_section,(abfd, section, symbols),
 984       bfd *abfd AND
 985       asection *section AND
 986       asymbol **symbols)
 987 {
 988
 989   return false;
 990
 991 }
 992
 993
 994 /*
 995 INTERNAL_FUNCTION
 996         bfd_generic_get_relocated_section_contents
 997
 998 SYNOPSIS
 999         bfd_byte *
1000            bfd_generic_get_relocated_section_contents (bfd *abfd,
1001              struct bfd_seclet *seclet,
1002              bfd_byte *data,
1003              boolean relocateable);
1004
1005 DESCRIPTION
1006         Provides default handling of relocation effort for back ends
1007         which can't be bothered to do it efficiently.
1008
1009 */
1010
1011 bfd_byte *
1012 DEFUN(bfd_generic_get_relocated_section_contents,(abfd,
1013                                                   seclet,
1014                                                   data,
1015                                                   relocateable),
1016       bfd *abfd AND
1017       struct bfd_seclet *seclet AND
1018       bfd_byte *data AND
1019       boolean relocateable)
1020 {
1021   extern bfd_error_vector_type bfd_error_vector;
1022
1023   /* Get enough memory to hold the stuff */
1024   bfd *input_bfd = seclet->u.indirect.section->owner;
1025   asection *input_section = seclet->u.indirect.section;
1026
1027
1028
1029   size_t reloc_size = bfd_get_reloc_upper_bound(input_bfd, input_section);
1030   arelent **reloc_vector = (arelent **) alloca(reloc_size);
1031
1032   /* read in the section */
1033   bfd_get_section_contents(input_bfd,
1034                            input_section,
1035                            data,
1036                            0,
1037                            input_section->_raw_size);
1038
1039 /* We're not relaxing the section, so just copy the size info */
1040   input_section->_cooked_size = input_section->_raw_size;
1041   input_section->reloc_done = true;
1042
1043
1044   if (bfd_canonicalize_reloc(input_bfd,
1045                              input_section,
1046                              reloc_vector,
1047                              seclet->u.indirect.symbols) )
1048   {
1049     arelent **parent;
1050     for (parent = reloc_vector;  * parent != (arelent *)NULL;
1051          parent++)
1052     {
1053       bfd_reloc_status_type r=
1054        bfd_perform_relocation(input_bfd,
1055                               *parent,
1056                               data,
1057                               input_section,
1058                               relocateable ? abfd : (bfd *) NULL);
1059
1060       if (relocateable)
1061         {
1062           asection *os = input_section->output_section;
1063
1064           /* A partial link, so keep the relocs */
1065           os->orelocation[os->reloc_count] = *parent;
1066           os->reloc_count++;
1067         }
1068
1069       if (r != bfd_reloc_ok)
1070       {
1071         switch (r)
1072         {
1073         case bfd_reloc_undefined:
1074           bfd_error_vector.undefined_symbol(*parent, seclet);
1075           break;
1076         case bfd_reloc_dangerous:
1077           bfd_error_vector.reloc_dangerous(*parent, seclet);
1078           break;
1079         case bfd_reloc_outofrange:
1080         case bfd_reloc_overflow:
1081           bfd_error_vector.reloc_value_truncated(*parent, seclet);
1082           break;
1083         default:
1084           abort();
1085           break;
1086         }
1087
1088       }
1089     }
1090   }
1091
1092
1093   return data;
1094
1095
1096 }