bfd/coff-a29k.c

   1 /* BFD back-end for AMD 29000 COFF binaries.
   2    Copyright 1990, 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
   3    Contributed by David Wood at New York University 7/8/91.
   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 #define A29K 1
  22
  23 #include "bfd.h"
  24 #include "sysdep.h"
  25 #include "libbfd.h"
  26 #include "obstack.h"
  27 #include "coff/a29k.h"
  28 #include "coff/internal.h"
  29 #include "libcoff.h"
  30
  31 static long get_symbol_value PARAMS ((asymbol *));
  32 static bfd_reloc_status_type a29k_reloc
  33   PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
  34 static boolean coff_a29k_relocate_section
  35   PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
  36            struct internal_reloc *, struct internal_syment *, asection **));
  37
  38 #define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2)
  39
  40 #define INSERT_HWORD(WORD,HWORD)        \
  41     (((WORD) & 0xff00ff00) | (((HWORD) & 0xff00) << 8) | ((HWORD)& 0xff))
  42 #define EXTRACT_HWORD(WORD) \
  43     (((WORD) & 0x00ff0000) >> 8) | ((WORD)& 0xff)
  44 #define SIGN_EXTEND_HWORD(HWORD) \
  45     ((HWORD) & 0x8000 ? (HWORD)|0xffff0000 : (HWORD))
  46
  47 /* Provided the symbol, returns the value reffed */
  48 static long
  49 get_symbol_value (symbol)
  50      asymbol *symbol;
  51 {
  52   long relocation = 0;
  53
  54   if (bfd_is_com_section (symbol->section))
  55   {
  56     relocation = 0;
  57   }
  58   else
  59   {
  60     relocation = symbol->value +
  61      symbol->section->output_section->vma +
  62       symbol->section->output_offset;
  63   }
  64
  65   return(relocation);
  66 }
  67
  68 /* this function is in charge of performing all the 29k relocations */
  69
  70 static bfd_reloc_status_type
  71 a29k_reloc (abfd, reloc_entry, symbol_in, data, input_section, output_bfd,
  72             error_message)
  73      bfd *abfd;
  74      arelent *reloc_entry;
  75      asymbol *symbol_in;
  76      PTR data;
  77      asection *input_section;
  78      bfd *output_bfd;
  79      char **error_message;
  80 {
  81   /* the consth relocation comes in two parts, we have to remember
  82      the state between calls, in these variables */
  83   static boolean part1_consth_active = false;
  84   static unsigned long part1_consth_value;
  85
  86   unsigned long insn;
  87   unsigned long sym_value;
  88   unsigned long unsigned_value;
  89   unsigned short r_type;
  90   long signed_value;
  91
  92   unsigned long addr = reloc_entry->address ; /*+ input_section->vma*/
  93   bfd_byte  *hit_data =addr + (bfd_byte *)(data);
  94
  95   r_type = reloc_entry->howto->type;
  96
  97   if (output_bfd) {
  98     /* Partial linking - do nothing */
  99     reloc_entry->address += input_section->output_offset;
 100     return bfd_reloc_ok;
 101
 102   }
 103
 104   if (symbol_in != NULL
 105       && bfd_is_und_section (symbol_in->section))
 106   {
 107     /* Keep the state machine happy in case we're called again */
 108     if (r_type == R_IHIHALF)
 109     {
 110       part1_consth_active = true;
 111       part1_consth_value  = 0;
 112     }
 113     return(bfd_reloc_undefined);
 114   }
 115
 116   if ((part1_consth_active) && (r_type != R_IHCONST))
 117   {
 118     part1_consth_active = false;
 119     *error_message = (char *) "Missing IHCONST";
 120     return(bfd_reloc_dangerous);
 121   }
 122
 123
 124   sym_value = get_symbol_value(symbol_in);
 125
 126   switch (r_type)
 127   {
 128    case R_IREL:
 129     insn = bfd_get_32(abfd, hit_data);
 130     /* Take the value in the field and sign extend it */
 131     signed_value = EXTRACT_HWORD(insn);
 132     signed_value = SIGN_EXTEND_HWORD(signed_value);
 133     signed_value <<= 2;
 134     signed_value +=  sym_value + reloc_entry->addend;
 135     if (((signed_value + reloc_entry->address) & ~0x3ffff) == 0)
 136     {                           /* Absolute jmp/call */
 137       insn |= (1<<24);          /* Make it absolute */
 138       signed_value += reloc_entry->address;
 139       /* FIXME: Should we change r_type to R_IABS */
 140     }
 141     else
 142     {
 143       /* Relative jmp/call, so subtract from the value the
 144          address of the place we're coming from */
 145       signed_value -= (input_section->output_section->vma
 146                        + input_section->output_offset);
 147       if (signed_value>0x1ffff || signed_value<-0x20000)
 148        return(bfd_reloc_overflow);
 149     }
 150     signed_value >>= 2;
 151     insn = INSERT_HWORD(insn, signed_value);
 152     bfd_put_32(abfd, insn ,hit_data);
 153     break;
 154    case R_ILOHALF:
 155     insn = bfd_get_32(abfd, hit_data);
 156     unsigned_value = EXTRACT_HWORD(insn);
 157     unsigned_value +=  sym_value + reloc_entry->addend;
 158     insn = INSERT_HWORD(insn, unsigned_value);
 159     bfd_put_32(abfd, insn, hit_data);
 160     break;
 161    case R_IHIHALF:
 162     insn = bfd_get_32(abfd, hit_data);
 163     /* consth, part 1
 164        Just get the symbol value that is referenced */
 165     part1_consth_active = true;
 166     part1_consth_value = sym_value + reloc_entry->addend;
 167     /* Don't modify insn until R_IHCONST */
 168     break;
 169    case R_IHCONST:
 170     insn = bfd_get_32(abfd, hit_data);
 171     /* consth, part 2
 172        Now relocate the reference */
 173     if (part1_consth_active == false) {
 174       *error_message = (char *) "Missing IHIHALF";
 175       return(bfd_reloc_dangerous);
 176     }
 177     /* sym_ptr_ptr = r_symndx, in coff_slurp_reloc_table() */
 178     unsigned_value = 0;         /*EXTRACT_HWORD(insn) << 16;*/
 179     unsigned_value += reloc_entry->addend; /* r_symndx */
 180     unsigned_value += part1_consth_value;
 181     unsigned_value = unsigned_value >> 16;
 182     insn = INSERT_HWORD(insn, unsigned_value);
 183     part1_consth_active = false;
 184     bfd_put_32(abfd, insn, hit_data);
 185     break;
 186    case R_BYTE:
 187     insn = bfd_get_8(abfd, hit_data);
 188     unsigned_value = insn + sym_value + reloc_entry->addend;
 189     if (unsigned_value & 0xffffff00) {
 190       fprintf(stderr,"Relocation problem : ");
 191       fprintf(stderr,"byte value too large in module %s\n",
 192               abfd->filename);
 193       return(bfd_reloc_overflow);
 194     }
 195     bfd_put_8(abfd, unsigned_value, hit_data);
 196     break;
 197    case R_HWORD:
 198     insn = bfd_get_16(abfd, hit_data);
 199     unsigned_value = insn + sym_value + reloc_entry->addend;
 200     if (unsigned_value & 0xffff0000) {
 201       fprintf(stderr,"Relocation problem : ");
 202       fprintf(stderr,"hword value too large in module %s\n",
 203               abfd->filename);
 204       return(bfd_reloc_overflow);
 205     }
 206
 207     bfd_put_16(abfd, insn, hit_data);
 208     break;
 209    case R_WORD:
 210     insn = bfd_get_32(abfd, hit_data);
 211     insn += sym_value + reloc_entry->addend;
 212     bfd_put_32(abfd, insn, hit_data);
 213     break;
 214    default:
 215     *error_message = "Unrecognized reloc";
 216     return (bfd_reloc_dangerous);
 217   }
 218
 219
 220   return(bfd_reloc_ok);
 221 }
 222
 223 /*      type       rightshift
 224                        size
 225                           bitsize
 226                                pc-relative
 227                                      bitpos
 228                                          absolute
 229                                              complain_on_overflow
 230                                                   special_function
 231                                                     relocation name
 232                                                                partial_inplace
 233                                                                       src_mask
 234 */
 235
 236 /*FIXME: I'm not real sure about this table */
 237 static reloc_howto_type howto_table[] =
 238 {
 239   {R_ABS,     0, 3, 32, false, 0, complain_overflow_bitfield,a29k_reloc,"ABS",     true, 0xffffffff,0xffffffff, false},
 240   {1},  {2},  {3},   {4},  {5},  {6},  {7},  {8},  {9}, {10},
 241   {11}, {12}, {13}, {14}, {15}, {16}, {17}, {18}, {19}, {20},
 242   {21}, {22}, {23},
 243   {R_IREL,    0, 3, 32, true,  0, complain_overflow_signed,a29k_reloc,"IREL",    true, 0xffffffff,0xffffffff, false},
 244   {R_IABS,    0, 3, 32, false, 0, complain_overflow_bitfield, a29k_reloc,"IABS",    true, 0xffffffff,0xffffffff, false},
 245   {R_ILOHALF, 0, 3, 16, true,  0, complain_overflow_signed, a29k_reloc,"ILOHALF", true, 0x0000ffff,0x0000ffff, false},
 246   {R_IHIHALF, 0, 3, 16, true,  16, complain_overflow_signed, a29k_reloc,"IHIHALF", true, 0xffff0000,0xffff0000, false},
 247   {R_IHCONST, 0, 3, 16, true,  0, complain_overflow_signed, a29k_reloc,"IHCONST", true, 0xffff0000,0xffff0000, false},
 248   {R_BYTE,    0, 0, 8, false, 0, complain_overflow_bitfield, a29k_reloc,"BYTE",    true, 0x000000ff,0x000000ff, false},
 249   {R_HWORD,   0, 1, 16, false, 0, complain_overflow_bitfield, a29k_reloc,"HWORD",   true, 0x0000ffff,0x0000ffff, false},
 250   {R_WORD,    0, 2, 32, false, 0, complain_overflow_bitfield, a29k_reloc,"WORD",    true, 0xffffffff,0xffffffff, false},
 251 };
 252
 253 #define BADMAG(x) A29KBADMAG(x)
 254
 255 #define RELOC_PROCESSING(relent, reloc, symbols, abfd, section) \
 256  reloc_processing(relent, reloc, symbols, abfd, section)
 257
 258 static void
 259 reloc_processing (relent,reloc, symbols, abfd, section)
 260      arelent *relent;
 261      struct internal_reloc *reloc;
 262      asymbol **symbols;
 263      bfd *abfd;
 264      asection *section;
 265 {
 266     static bfd_vma ihihalf_vaddr = (bfd_vma) -1;
 267
 268     relent->address = reloc->r_vaddr;
 269     relent->howto = howto_table + reloc->r_type;
 270     if (reloc->r_type == R_IHCONST)
 271     {
 272       /* The address of an R_IHCONST should always be the address of
 273          the immediately preceding R_IHIHALF.  relocs generated by gas
 274          are correct, but relocs generated by High C are different (I
 275          can't figure out what the address means for High C).  We can
 276          handle both gas and High C by ignoring the address here, and
 277          simply reusing the address saved for R_IHIHALF.  */
 278         if (ihihalf_vaddr == (bfd_vma) -1)
 279           abort ();
 280         relent->address = ihihalf_vaddr;
 281         ihihalf_vaddr = (bfd_vma) -1;
 282         relent->addend = reloc->r_symndx;
 283         relent->sym_ptr_ptr= bfd_abs_section_ptr->symbol_ptr_ptr;
 284     }
 285     else
 286     {
 287       asymbol *ptr;
 288       relent->sym_ptr_ptr = symbols + obj_convert(abfd)[reloc->r_symndx];
 289
 290       ptr = *(relent->sym_ptr_ptr);
 291
 292       if (ptr
 293           && bfd_asymbol_bfd(ptr) == abfd
 294
 295           && ((ptr->flags & BSF_OLD_COMMON)== 0))
 296       {
 297           relent->addend = 0;
 298       }
 299       else
 300       {
 301           relent->addend = 0;
 302       }
 303       relent->address-= section->vma;
 304       if (reloc->r_type == R_IHIHALF)
 305         ihihalf_vaddr = relent->address;
 306       else if (ihihalf_vaddr != (bfd_vma) -1)
 307         abort ();
 308   }
 309 }
 310
 311 /* The reloc processing routine for the optimized COFF linker.  */
 312
 313 static boolean
 314 coff_a29k_relocate_section (output_bfd, info, input_bfd, input_section,
 315                             contents, relocs, syms, sections)
 316      bfd *output_bfd;
 317      struct bfd_link_info *info;
 318      bfd *input_bfd;
 319      asection *input_section;
 320      bfd_byte *contents;
 321      struct internal_reloc *relocs;
 322      struct internal_syment *syms;
 323      asection **sections;
 324 {
 325   struct internal_reloc *rel;
 326   struct internal_reloc *relend;
 327   boolean hihalf;
 328   bfd_vma hihalf_val;
 329
 330   /* If we are performing a relocateable link, we don't need to do a
 331      thing.  The caller will take care of adjusting the reloc
 332      addresses and symbol indices.  */
 333   if (info->relocateable)
 334     return true;
 335
 336   hihalf = false;
 337   hihalf_val = 0;
 338
 339   rel = relocs;
 340   relend = rel + input_section->reloc_count;
 341   for (; rel < relend; rel++)
 342     {
 343       long symndx;
 344       bfd_byte *loc;
 345       struct coff_link_hash_entry *h;
 346       struct internal_syment *sym;
 347       asection *sec;
 348       bfd_vma val;
 349       boolean overflow;
 350       unsigned long insn;
 351       long signed_value;
 352       unsigned long unsigned_value;
 353       bfd_reloc_status_type rstat;
 354
 355       symndx = rel->r_symndx;
 356       loc = contents + rel->r_vaddr - input_section->vma;
 357
 358       if (symndx == -1)
 359         h = NULL;
 360       else
 361         h = obj_coff_sym_hashes (input_bfd)[symndx];
 362
 363       sym = NULL;
 364       sec = NULL;
 365       val = 0;
 366
 367       /* An R_IHCONST reloc does not have a symbol.  Instead, the
 368          symbol index is an addend.  R_IHCONST is always used in
 369          conjunction with R_IHHALF.  */
 370       if (rel->r_type != R_IHCONST)
 371         {
 372           if (h == NULL)
 373             {
 374               if (symndx == -1)
 375                 sec = bfd_abs_section_ptr;
 376               else
 377                 {
 378                   sym = syms + symndx;
 379                   sec = sections[symndx];
 380                   val = (sec->output_section->vma
 381                          + sec->output_offset
 382                          + sym->n_value
 383                          - sec->vma);
 384                 }
 385             }
 386           else
 387             {
 388               if (h->root.type == bfd_link_hash_defined)
 389                 {
 390                   sec = h->root.u.def.section;
 391                   val = (h->root.u.def.value
 392                          + sec->output_section->vma
 393                          + sec->output_offset);
 394                 }
 395               else
 396                 {
 397                   if (! ((*info->callbacks->undefined_symbol)
 398                          (info, h->root.root.string, input_bfd, input_section,
 399                           rel->r_vaddr - input_section->vma)))
 400                     return false;
 401                 }
 402             }
 403
 404           if (hihalf)
 405             {
 406               if (! ((*info->callbacks->reloc_dangerous)
 407                      (info, "missing IHCONST reloc", input_bfd,
 408                       input_section, rel->r_vaddr - input_section->vma)))
 409                 return false;
 410               hihalf = false;
 411             }
 412         }
 413
 414       overflow = false;
 415
 416       switch (rel->r_type)
 417         {
 418         default:
 419           bfd_set_error (bfd_error_bad_value);
 420           return false;
 421
 422         case R_IREL:
 423           insn = bfd_get_32 (input_bfd, loc);
 424
 425           /* Extract the addend.  */
 426           signed_value = EXTRACT_HWORD (insn);
 427           signed_value = SIGN_EXTEND_HWORD (signed_value);
 428           signed_value <<= 2;
 429
 430           /* Determine the destination of the jump.  */
 431           signed_value += val + rel->r_vaddr - input_section->vma;
 432
 433           if ((signed_value & ~0x3ffff) == 0)
 434             {
 435               /* We can use an absolute jump.  */
 436               insn |= (1 << 24);
 437             }
 438           else
 439             {
 440               /* Make the destination PC relative.  */
 441               signed_value -= (input_section->output_section->vma
 442                                + input_section->output_offset
 443                                + (rel->r_vaddr - input_section->vma));
 444               if (signed_value > 0x1ffff || signed_value < - 0x20000)
 445                 {
 446                   overflow = true;
 447                   signed_value = 0;
 448                 }
 449             }
 450
 451           /* Put the adjusted value back into the instruction.  */
 452           signed_value >>= 2;
 453           insn = INSERT_HWORD (insn, signed_value);
 454
 455           bfd_put_32 (input_bfd, (bfd_vma) insn, loc);
 456
 457           break;
 458
 459         case R_ILOHALF:
 460           insn = bfd_get_32 (input_bfd, loc);
 461           unsigned_value = EXTRACT_HWORD (insn);
 462           unsigned_value += val;
 463           insn = INSERT_HWORD (insn, unsigned_value);
 464           bfd_put_32 (input_bfd, insn, loc);
 465           break;
 466
 467         case R_IHIHALF:
 468           /* Save the value for the R_IHCONST reloc.  */
 469           hihalf = true;
 470           hihalf_val = val;
 471           break;
 472
 473         case R_IHCONST:
 474           if (! hihalf)
 475             {
 476               if (! ((*info->callbacks->reloc_dangerous)
 477                      (info, "missing IHIHALF reloc", input_bfd,
 478                       input_section, rel->r_vaddr - input_section->vma)))
 479                 return false;
 480               hihalf_val = 0;
 481             }
 482
 483           insn = bfd_get_32 (input_bfd, loc);
 484           unsigned_value = rel->r_symndx + hihalf_val;
 485           unsigned_value >>= 16;
 486           insn = INSERT_HWORD (insn, unsigned_value);
 487           bfd_put_32 (input_bfd, (bfd_vma) insn, loc);
 488
 489           hihalf = false;
 490
 491           break;
 492
 493         case R_BYTE:
 494         case R_HWORD:
 495         case R_WORD:
 496           rstat = _bfd_relocate_contents (howto_table + rel->r_type,
 497                                           input_bfd, val, loc);
 498           if (rstat == bfd_reloc_overflow)
 499             overflow = true;
 500           else if (rstat != bfd_reloc_ok)
 501             abort ();
 502           break;
 503         }
 504
 505       if (overflow)
 506         {
 507           const char *name;
 508           char buf[SYMNMLEN + 1];
 509
 510           if (symndx == -1)
 511             name = "*ABS*";
 512           else if (h != NULL)
 513             name = h->root.root.string;
 514           else if (sym == NULL)
 515             name = "*unknown*";
 516           else if (sym->_n._n_n._n_zeroes == 0
 517                    && sym->_n._n_n._n_offset != 0)
 518             name = obj_coff_strings (input_bfd) + sym->_n._n_n._n_offset;
 519           else
 520             {
 521               strncpy (buf, sym->_n._n_name, SYMNMLEN);
 522               buf[SYMNMLEN] = '\0';
 523               name = buf;
 524             }
 525
 526           if (! ((*info->callbacks->reloc_overflow)
 527                  (info, name, howto_table[rel->r_type].name, (bfd_vma) 0,
 528                   input_bfd, input_section,
 529                   rel->r_vaddr - input_section->vma)))
 530             return false;
 531         }
 532     }
 533
 534   return true;
 535 }
 536
 537 #define coff_relocate_section coff_a29k_relocate_section
 538
 539 #include "coffcode.h"
 540
 541 const bfd_target a29kcoff_big_vec =
 542 {
 543   "coff-a29k-big",              /* name */
 544   bfd_target_coff_flavour,
 545   true,                         /* data byte order is big */
 546   true,                         /* header byte order is big */
 547
 548   (HAS_RELOC | EXEC_P |         /* object flags */
 549    HAS_LINENO | HAS_DEBUG |
 550    HAS_SYMS | HAS_LOCALS | WP_TEXT),
 551
 552   (SEC_HAS_CONTENTS | SEC_ALLOC /* section flags */
 553    | SEC_LOAD | SEC_RELOC
 554    | SEC_READONLY ),
 555   '_',                          /* leading underscore */
 556   '/',                          /* ar_pad_char */
 557   15,                           /* ar_max_namelen */
 558   2,                            /* minimum section alignment */
 559   /* data */
 560   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 561      bfd_getb32, bfd_getb_signed_32,   bfd_putb32,
 562      bfd_getb16, bfd_getb_signed_16, bfd_putb16,
 563   /* hdrs */
 564   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 565      bfd_getb32, bfd_getb_signed_32,   bfd_putb32,
 566      bfd_getb16, bfd_getb_signed_16, bfd_putb16,
 567
 568  {
 569
 570    _bfd_dummy_target,
 571    coff_object_p,
 572    bfd_generic_archive_p,
 573    _bfd_dummy_target
 574   },
 575  {
 576    bfd_false,
 577    coff_mkobject,
 578    _bfd_generic_mkarchive,
 579    bfd_false
 580   },
 581  {
 582    bfd_false,
 583    coff_write_object_contents,
 584    _bfd_write_archive_contents,
 585    bfd_false
 586   },
 587
 588      BFD_JUMP_TABLE_GENERIC (coff),
 589      BFD_JUMP_TABLE_COPY (coff),
 590      BFD_JUMP_TABLE_CORE (_bfd_nocore),
 591      BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff),
 592      BFD_JUMP_TABLE_SYMBOLS (coff),
 593      BFD_JUMP_TABLE_RELOCS (coff),
 594      BFD_JUMP_TABLE_WRITE (coff),
 595      BFD_JUMP_TABLE_LINK (coff),
 596      BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 597
 598   COFF_SWAP_TABLE
 599  };