bfd/coff-mcore.c

   1 /* BFD back-end for Motorola MCore COFF/PE
   2    Copyright (C) 1999-2015 Free Software Foundation, Inc.
   3
   4    This file is part of BFD, the Binary File Descriptor library.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, 51 Franklin Street - Fifth Floor,
  19    Boston, MA 02110-1301, USA.  */
  20
  21 #include "sysdep.h"
  22 #include "bfd.h"
  23 #include "libbfd.h"
  24 #include "coff/mcore.h"
  25 #include "coff/internal.h"
  26 #include "coff/pe.h"
  27 #include "libcoff.h"
  28
  29 #ifdef BADMAG
  30 #undef BADMAG
  31 #endif
  32 #define BADMAG(x) MCOREBADMAG(x)
  33
  34 #ifndef NUM_ELEM
  35 #define NUM_ELEM(A) (sizeof (A) / sizeof (A)[0])
  36 #endif
  37
  38 /* This file is compiled more than once, but we only compile the
  39    final_link routine once.  */
  40 extern bfd_boolean mcore_bfd_coff_final_link
  41   (bfd *, struct bfd_link_info *);
  42 static bfd_reloc_status_type mcore_coff_unsupported_reloc
  43   (bfd *, arelent *, asymbol *, void *, asection *, bfd *, char **);
  44
  45 \f
  46 /* The NT loader points the toc register to &toc + 32768, in order to
  47    use the complete range of a 16-bit displacement. We have to adjust
  48    for this when we fix up loads displaced off the toc reg.  */
  49 #define TOC_LOAD_ADJUSTMENT (-32768)
  50 #define TOC_SECTION_NAME ".private.toc"
  51
  52 /* The main body of code is in coffcode.h.  */
  53 #define COFF_DEFAULT_SECTION_ALIGNMENT_POWER 2
  54
  55 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value
  56    from smaller values.  Start with zero, widen, *then* decrement.  */
  57 #define MINUS_ONE       (((bfd_vma)0) - 1)
  58 \f
  59 static reloc_howto_type mcore_coff_howto_table[] =
  60 {
  61   /* Unused: */
  62   HOWTO (IMAGE_REL_MCORE_ABSOLUTE,/* type */
  63          0,                      /* rightshift */
  64          0,                      /* size (0 = byte, 1 = short, 2 = long) */
  65          0,                      /* bitsize */
  66          FALSE,                  /* pc_relative */
  67          0,                      /* bitpos */
  68          complain_overflow_dont, /* dont complain_on_overflow */
  69          NULL,                   /* special_function */
  70          "ABSOLUTE",             /* name */
  71          FALSE,                  /* partial_inplace */
  72          0x00,                   /* src_mask */
  73          0x00,                   /* dst_mask */
  74          FALSE),                 /* pcrel_offset */
  75
  76   HOWTO (IMAGE_REL_MCORE_ADDR32,/* type */
  77          0,                     /* rightshift */
  78          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  79          32,                    /* bitsize */
  80          FALSE,                 /* pc_relative */
  81          0,                     /* bitpos */
  82          complain_overflow_bitfield, /* complain_on_overflow */
  83          NULL,                  /* special_function */
  84          "ADDR32",              /* name */
  85          TRUE,                  /* partial_inplace */
  86          0xffffffff,            /* src_mask */
  87          0xffffffff,            /* dst_mask */
  88          FALSE),                /* pcrel_offset */
  89
  90   /* 8 bits + 2 zero bits; jmpi/jsri/lrw instructions.
  91      Should not appear in object files.  */
  92   HOWTO (IMAGE_REL_MCORE_PCREL_IMM8BY4, /* type */
  93          2,                     /* rightshift */
  94          1,                     /* size (0 = byte, 1 = short, 2 = long) */
  95          8,                     /* bitsize */
  96          TRUE,                  /* pc_relative */
  97          0,                     /* bitpos */
  98          complain_overflow_bitfield, /* complain_on_overflow */
  99          mcore_coff_unsupported_reloc, /* special_function */
 100          "IMM8BY4",             /* name */
 101          FALSE,                 /* partial_inplace */
 102          0,                     /* src_mask */
 103          0,                     /* dst_mask */
 104          TRUE),                 /* pcrel_offset */
 105
 106   /* bsr/bt/bf/br instructions; 11 bits + 1 zero bit
 107      Span 2k instructions == 4k bytes.
 108      Only useful pieces at the relocated address are the opcode (5 bits) */
 109   HOWTO (IMAGE_REL_MCORE_PCREL_IMM11BY2,/* type */
 110          1,                     /* rightshift */
 111          1,                     /* size (0 = byte, 1 = short, 2 = long) */
 112          11,                    /* bitsize */
 113          TRUE,                  /* pc_relative */
 114          0,                     /* bitpos */
 115          complain_overflow_signed, /* complain_on_overflow */
 116          NULL,                  /* special_function */
 117          "IMM11BY2",            /* name */
 118          FALSE,                 /* partial_inplace */
 119          0x0,                   /* src_mask */
 120          0x7ff,                 /* dst_mask */
 121          TRUE),                 /* pcrel_offset */
 122
 123   /* 4 bits + 1 zero bit; 'loopt' instruction only; unsupported.  */
 124   HOWTO (IMAGE_REL_MCORE_PCREL_IMM4BY2, /* type */
 125          1,                     /* rightshift */
 126          1,                     /* size (0 = byte, 1 = short, 2 = long) */
 127          4,                     /* bitsize */
 128          TRUE,                  /* pc_relative */
 129          0,                     /* bitpos */
 130          complain_overflow_bitfield, /* complain_on_overflow */
 131          mcore_coff_unsupported_reloc, /* special_function */
 132          "IMM4BY2",              /* name */
 133          FALSE,                 /* partial_inplace */
 134          0,                     /* src_mask */
 135          0,                     /* dst_mask */
 136          TRUE),                 /* pcrel_offset */
 137
 138   /* 32-bit pc-relative. Eventually this will help support PIC code.  */
 139   HOWTO (IMAGE_REL_MCORE_PCREL_32,/* type */
 140          0,                     /* rightshift */
 141          2,                     /* size (0 = byte, 1 = short, 2 = long) */
 142          32,                    /* bitsize */
 143          TRUE,                  /* pc_relative */
 144          0,                     /* bitpos */
 145          complain_overflow_bitfield, /* complain_on_overflow */
 146          NULL,                  /* special_function */
 147          "PCREL_32",            /* name */
 148          FALSE,                 /* partial_inplace */
 149          0x0,                   /* src_mask */
 150          0xffffffff,            /* dst_mask */
 151          TRUE),                 /* pcrel_offset */
 152
 153   /* Like PCREL_IMM11BY2, this relocation indicates that there is a
 154      'jsri' at the specified address. There is a separate relocation
 155      entry for the literal pool entry that it references, but we
 156      might be able to change the jsri to a bsr if the target turns out
 157      to be close enough [even though we won't reclaim the literal pool
 158      entry, we'll get some runtime efficiency back]. Note that this
 159      is a relocation that we are allowed to safely ignore.  */
 160   HOWTO (IMAGE_REL_MCORE_PCREL_JSR_IMM11BY2,/* type */
 161          1,                     /* rightshift */
 162          1,                     /* size (0 = byte, 1 = short, 2 = long) */
 163          11,                    /* bitsize */
 164          TRUE,                  /* pc_relative */
 165          0,                     /* bitpos */
 166          complain_overflow_signed, /* complain_on_overflow */
 167          NULL,                  /* special_function */
 168          "JSR_IMM11BY2",        /* name */
 169          FALSE,                 /* partial_inplace */
 170          0x0,                   /* src_mask */
 171          0x7ff,                 /* dst_mask */
 172          TRUE),                 /* pcrel_offset */
 173
 174   HOWTO (IMAGE_REL_MCORE_RVA,   /* type */
 175          0,                     /* rightshift */
 176          2,                     /* size (0 = byte, 1 = short, 2 = long) */
 177          32,                    /* bitsize */
 178          FALSE,                 /* pc_relative */
 179          0,                     /* bitpos */
 180          complain_overflow_signed, /* complain_on_overflow */
 181          NULL,                  /* special_function */
 182          "MCORE_RVA",           /* name */
 183          TRUE,                  /* partial_inplace */
 184          0xffffffff,            /* src_mask */
 185          0xffffffff,            /* dst_mask */
 186          TRUE)                  /* pcrel_offset */
 187 };
 188 \f
 189 /* Extend the coff_link_hash_table structure with a few M*Core specific fields.
 190    This allows us to store global data here without actually creating any
 191    global variables, which is a no-no in the BFD world.  */
 192 typedef struct coff_mcore_link_hash_table
 193 {
 194   /* The original coff_link_hash_table structure.  MUST be first field.  */
 195   struct coff_link_hash_table   root;
 196
 197   bfd *                         bfd_of_toc_owner;
 198   long int                      global_toc_size;
 199   long int                      import_table_size;
 200   long int                      first_thunk_address;
 201   long int                      thunk_size;
 202 }
 203 mcore_hash_table;
 204
 205 /* Get the MCore coff linker hash table from a link_info structure.  */
 206 #define coff_mcore_hash_table(info) \
 207   ((mcore_hash_table *) ((info)->hash))
 208
 209 \f
 210 /* Add an entry to the base file.  */
 211
 212 static bfd_boolean
 213 mcore_emit_base_file_entry (struct bfd_link_info *info,
 214                             bfd *output_bfd,
 215                             asection *input_section,
 216                             bfd_vma reloc_offset)
 217 {
 218   bfd_vma addr = reloc_offset
 219                  - input_section->vma
 220                  + input_section->output_offset
 221                  + input_section->output_section->vma;
 222
 223   if (coff_data (output_bfd)->pe)
 224      addr -= pe_data (output_bfd)->pe_opthdr.ImageBase;
 225
 226   if (fwrite (&addr, sizeof (addr), 1, (FILE *) info->base_file) == 1)
 227     return TRUE;
 228
 229   bfd_set_error (bfd_error_system_call);
 230   return FALSE;
 231 }
 232 \f
 233 static bfd_reloc_status_type
 234 mcore_coff_unsupported_reloc (bfd * abfd,
 235                               arelent * reloc_entry,
 236                               asymbol * symbol ATTRIBUTE_UNUSED,
 237                               void * data ATTRIBUTE_UNUSED,
 238                               asection * input_section ATTRIBUTE_UNUSED,
 239                               bfd * output_bfd ATTRIBUTE_UNUSED,
 240                               char ** error_message ATTRIBUTE_UNUSED)
 241 {
 242   BFD_ASSERT (reloc_entry->howto != (reloc_howto_type *)0);
 243
 244   _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
 245                       abfd,
 246                       reloc_entry->howto->name,
 247                       reloc_entry->howto->type);
 248
 249   return bfd_reloc_notsupported;
 250 }
 251 \f
 252 /* A cheesy little macro to make the code a little more readable.  */
 253 #define HOW2MAP(bfd_rtype, mcore_rtype)  \
 254  case bfd_rtype: return & mcore_coff_howto_table [mcore_rtype]
 255
 256 static reloc_howto_type *
 257 mcore_coff_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
 258                               bfd_reloc_code_real_type code)
 259 {
 260   switch (code)
 261     {
 262       HOW2MAP (BFD_RELOC_32,                       IMAGE_REL_MCORE_ADDR32);
 263       HOW2MAP (BFD_RELOC_MCORE_PCREL_IMM8BY4,      IMAGE_REL_MCORE_PCREL_IMM8BY4);
 264       HOW2MAP (BFD_RELOC_MCORE_PCREL_IMM11BY2,     IMAGE_REL_MCORE_PCREL_IMM11BY2);
 265       HOW2MAP (BFD_RELOC_MCORE_PCREL_IMM4BY2,      IMAGE_REL_MCORE_PCREL_IMM4BY2);
 266       HOW2MAP (BFD_RELOC_32_PCREL,                 IMAGE_REL_MCORE_PCREL_32);
 267       HOW2MAP (BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2, IMAGE_REL_MCORE_PCREL_JSR_IMM11BY2);
 268       HOW2MAP (BFD_RELOC_RVA,                      IMAGE_REL_MCORE_RVA);
 269    default:
 270       return NULL;
 271     }
 272   /*NOTREACHED*/
 273 }
 274 #undef HOW2MAP
 275
 276 #define NUM_HOWTOS NUM_ELEM (mcore_coff_howto_table)
 277
 278 static reloc_howto_type *
 279 mcore_coff_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 280                               const char *r_name)
 281 {
 282   unsigned int i;
 283
 284   for (i = 0; i < NUM_HOWTOS; i++)
 285     if (mcore_coff_howto_table[i].name != NULL
 286         && strcasecmp (mcore_coff_howto_table[i].name, r_name) == 0)
 287       return &mcore_coff_howto_table[i];
 288
 289   return NULL;
 290 }
 291
 292 #define RTYPE2HOWTO(cache_ptr, dst)                             \
 293   ((cache_ptr)->howto =                                         \
 294    ((dst)->r_type < NUM_HOWTOS                                  \
 295     ? mcore_coff_howto_table + (dst)->r_type                    \
 296     : NULL))
 297
 298 static reloc_howto_type *
 299 coff_mcore_rtype_to_howto (bfd * abfd ATTRIBUTE_UNUSED,
 300                            asection * sec,
 301                            struct internal_reloc * rel,
 302                            struct coff_link_hash_entry * h ATTRIBUTE_UNUSED,
 303                            struct internal_syment * sym,
 304                            bfd_vma * addendp)
 305 {
 306   reloc_howto_type * howto;
 307
 308   if (rel->r_type >= NUM_HOWTOS)
 309     return NULL;
 310
 311   howto = mcore_coff_howto_table + rel->r_type;
 312
 313   if (rel->r_type == IMAGE_REL_MCORE_RVA)
 314     * addendp -= pe_data (sec->output_section->owner)->pe_opthdr.ImageBase;
 315
 316   else if (howto->pc_relative)
 317     {
 318       * addendp = sec->vma - 2; /* XXX guess - is this right ? */
 319
 320       /* If the symbol is defined, then the generic code is going to
 321          add back the symbol value in order to cancel out an
 322          adjustment it made to the addend.  However, we set the addend
 323          to 0 at the start of this function.  We need to adjust here,
 324          to avoid the adjustment the generic code will make.  FIXME:
 325          This is getting a bit hackish.  */
 326       if (sym != NULL && sym->n_scnum != 0)
 327         * addendp -= sym->n_value;
 328     }
 329   else
 330     * addendp = 0;
 331
 332   return howto;
 333 }
 334
 335 /* Return TRUE if this relocation should appear in the output .reloc section.
 336    This function is referenced in pe_mkobject in peicode.h.  */
 337
 338 static bfd_boolean
 339 in_reloc_p (bfd * abfd ATTRIBUTE_UNUSED, reloc_howto_type * howto)
 340 {
 341   return ! howto->pc_relative && howto->type != IMAGE_REL_MCORE_RVA;
 342 }
 343 \f
 344 /* The reloc processing routine for the optimized COFF linker.  */
 345 static bfd_boolean
 346 coff_mcore_relocate_section (bfd * output_bfd,
 347                              struct bfd_link_info * info,
 348                              bfd * input_bfd,
 349                              asection * input_section,
 350                              bfd_byte * contents,
 351                              struct internal_reloc * relocs,
 352                              struct internal_syment * syms,
 353                              asection ** sections)
 354 {
 355   struct internal_reloc * rel;
 356   struct internal_reloc * relend;
 357
 358   /* If we are performing a relocatable link, we don't need to do a
 359      thing.  The caller will take care of adjusting the reloc
 360      addresses and symbol indices.  */
 361   if (info->relocatable)
 362     return TRUE;
 363
 364   /* Check if we have the same endianness */
 365   if (   input_bfd->xvec->byteorder != output_bfd->xvec->byteorder
 366       && output_bfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN)
 367     {
 368       (*_bfd_error_handler)
 369         (_("%B: compiled for a %s system and target is %s.\n"),
 370          input_bfd,
 371          bfd_big_endian (input_bfd) ? _("big endian") : _("little endian"),
 372          bfd_big_endian (output_bfd) ? _("big endian") : _("little endian"));
 373
 374       bfd_set_error (bfd_error_wrong_format);
 375       return FALSE;
 376     }
 377
 378   rel = relocs;
 379   relend = rel + input_section->reloc_count;
 380
 381   for (; rel < relend; rel++)
 382     {
 383       long                           symndx;
 384       struct internal_syment *       sym;
 385       bfd_vma                        val;
 386       bfd_vma                        addend;
 387       bfd_reloc_status_type          rstat;
 388       bfd_byte *                     loc;
 389       unsigned short                 r_type = rel->r_type;
 390       reloc_howto_type *             howto = NULL;
 391       struct coff_link_hash_entry *  h;
 392       const char *                   my_name;
 393
 394       symndx = rel->r_symndx;
 395       loc = contents + rel->r_vaddr - input_section->vma;
 396
 397       if (symndx == -1)
 398         {
 399           h = NULL;
 400           sym = NULL;
 401         }
 402       else
 403         {
 404           h = obj_coff_sym_hashes (input_bfd)[symndx];
 405           sym = syms + symndx;
 406         }
 407
 408       addend = 0;
 409
 410       /* Get the howto and initialise the addend.  */
 411       howto = bfd_coff_rtype_to_howto (input_bfd, input_section, rel, h,
 412                                        sym, & addend);
 413       if (howto == NULL)
 414         return FALSE;
 415
 416       val = 0;
 417
 418       if (h == NULL)
 419         {
 420           if (symndx == -1)
 421             my_name = "*ABS*";
 422           else
 423             {
 424               asection * sec = sections[symndx];
 425
 426               val = (sym->n_value
 427                      + sec->output_section->vma
 428                      + sec->output_offset);
 429
 430               if (sym == NULL)
 431                 my_name = "*unknown*";
 432               else if (   sym->_n._n_n._n_zeroes == 0
 433                        && sym->_n._n_n._n_offset != 0)
 434                 my_name = obj_coff_strings (input_bfd) + sym->_n._n_n._n_offset;
 435               else
 436                 {
 437                   static char buf [SYMNMLEN + 1];
 438
 439                   strncpy (buf, sym->_n._n_name, SYMNMLEN);
 440                   buf[SYMNMLEN] = '\0';
 441                   my_name = buf;
 442                 }
 443             }
 444         }
 445       else
 446         {
 447           if (   h->root.type == bfd_link_hash_defined
 448               || h->root.type == bfd_link_hash_defweak)
 449             {
 450               asection * sec = h->root.u.def.section;
 451
 452               val = (h->root.u.def.value
 453                      + sec->output_section->vma
 454                      + sec->output_offset);
 455             }
 456           else
 457             {
 458               if (! ((*info->callbacks->undefined_symbol)
 459                      (info, h->root.root.string, input_bfd, input_section,
 460                       rel->r_vaddr - input_section->vma, TRUE)))
 461                 return FALSE;
 462             }
 463
 464           my_name = h->root.root.string;
 465         }
 466
 467       rstat = bfd_reloc_ok;
 468
 469       /* Each case must do its own relocation, setting rstat appropriately.  */
 470       switch (r_type)
 471         {
 472         default:
 473           _bfd_error_handler (_("%B: unsupported relocation type 0x%02x"),
 474                               input_bfd, r_type);
 475           bfd_set_error (bfd_error_bad_value);
 476           return FALSE;
 477
 478         case IMAGE_REL_MCORE_ABSOLUTE:
 479           _bfd_error_handler
 480             (_("Warning: unsupported reloc %s <file %B, section %A>\n"
 481                "sym %ld (%s), r_vaddr %ld (%lx)"),
 482              input_bfd, input_section, howto->name,
 483              rel->r_symndx, my_name, (long) rel->r_vaddr,
 484              (unsigned long) rel->r_vaddr);
 485           break;
 486
 487         case IMAGE_REL_MCORE_PCREL_IMM8BY4:
 488         case IMAGE_REL_MCORE_PCREL_IMM11BY2:
 489         case IMAGE_REL_MCORE_PCREL_IMM4BY2:
 490         case IMAGE_REL_MCORE_PCREL_32:
 491         case IMAGE_REL_MCORE_PCREL_JSR_IMM11BY2:
 492         case IMAGE_REL_MCORE_ADDR32:
 493           /* XXX fixme - shouldn't this be like the code for the RVA reloc ? */
 494           rstat = _bfd_relocate_contents (howto, input_bfd, val, loc);
 495           break;
 496
 497         case IMAGE_REL_MCORE_RVA:
 498           rstat = _bfd_final_link_relocate
 499             (howto, input_bfd,
 500              input_section, contents, rel->r_vaddr - input_section->vma,
 501              val, addend);
 502           break;
 503         }
 504
 505       /* Emit a reloc if the backend thinks it needs it.  */
 506       if (info->base_file
 507           && sym
 508           && pe_data (output_bfd)->in_reloc_p (output_bfd, howto)
 509           && !mcore_emit_base_file_entry (info, output_bfd, input_section,
 510                                           rel->r_vaddr))
 511         return FALSE;
 512
 513       switch (rstat)
 514         {
 515         default:
 516           abort ();
 517
 518         case bfd_reloc_ok:
 519           break;
 520
 521         case bfd_reloc_overflow:
 522           if (! ((*info->callbacks->reloc_overflow)
 523                  (info, (h ? &h->root : NULL), my_name, howto->name,
 524                   (bfd_vma) 0, input_bfd,
 525                   input_section, rel->r_vaddr - input_section->vma)))
 526             return FALSE;
 527         }
 528     }
 529
 530   return TRUE;
 531 }
 532 \f
 533 /* Tailor coffcode.h -- macro heaven.  */
 534
 535 /* We use the special COFF backend linker, with our own special touch.  */
 536
 537 #define coff_bfd_reloc_type_lookup   mcore_coff_reloc_type_lookup
 538 #define coff_bfd_reloc_name_lookup mcore_coff_reloc_name_lookup
 539 #define coff_relocate_section        coff_mcore_relocate_section
 540 #define coff_rtype_to_howto          coff_mcore_rtype_to_howto
 541
 542 #define SELECT_RELOC(internal, howto) {internal.r_type = howto->type;}
 543
 544 /* Make sure that the 'r_offset' field is copied properly
 545    so that identical binaries will compare the same.  */
 546 #define SWAP_IN_RELOC_OFFSET         H_GET_32
 547 #define SWAP_OUT_RELOC_OFFSET        H_PUT_32
 548
 549 #define COFF_PAGE_SIZE               0x1000
 550
 551 #include "coffcode.h"
 552 \f
 553 /* Forward declaration to initialise alternative_target field.  */
 554 extern const bfd_target TARGET_LITTLE_SYM;
 555
 556 /* The transfer vectors that lead the outside world to all of the above.  */
 557 CREATE_BIG_COFF_TARGET_VEC (TARGET_BIG_SYM, TARGET_BIG_NAME, D_PAGED,
 558                             (SEC_CODE | SEC_DATA | SEC_DEBUGGING | SEC_READONLY | SEC_LINK_ONCE | SEC_LINK_DUPLICATES),
 559                             0, & TARGET_LITTLE_SYM, COFF_SWAP_TABLE)
 560 CREATE_LITTLE_COFF_TARGET_VEC (TARGET_LITTLE_SYM, TARGET_LITTLE_NAME, D_PAGED,
 561                                (SEC_CODE | SEC_DATA | SEC_DEBUGGING | SEC_READONLY | SEC_LINK_ONCE | SEC_LINK_DUPLICATES),
 562                                0, & TARGET_BIG_SYM, COFF_SWAP_TABLE)