bfd/coff-mcore.c

   1 /* BFD back-end for Motorola MCore COFF/PE
   2    Copyright (C) 1999-2023 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 bool 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 */
  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          4,                     /* size */
  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          2,                     /* size */
  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          2,                     /* size */
 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          2,                     /* size */
 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          4,                     /* size */
 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          2,                     /* size */
 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          4,                     /* size */
 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 bool
 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 (obj_pe (output_bfd))
 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   /* xgettext: c-format */
 245   _bfd_error_handler (_("%pB: Relocation %s (%d) is not currently supported.\n"),
 246                       abfd,
 247                       reloc_entry->howto->name,
 248                       reloc_entry->howto->type);
 249
 250   return bfd_reloc_notsupported;
 251 }
 252 \f
 253 /* A cheesy little macro to make the code a little more readable.  */
 254 #define HOW2MAP(bfd_rtype, mcore_rtype)  \
 255  case bfd_rtype: return & mcore_coff_howto_table [mcore_rtype]
 256
 257 static reloc_howto_type *
 258 mcore_coff_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
 259                               bfd_reloc_code_real_type code)
 260 {
 261   switch (code)
 262     {
 263       HOW2MAP (BFD_RELOC_32,                       IMAGE_REL_MCORE_ADDR32);
 264       HOW2MAP (BFD_RELOC_MCORE_PCREL_IMM8BY4,      IMAGE_REL_MCORE_PCREL_IMM8BY4);
 265       HOW2MAP (BFD_RELOC_MCORE_PCREL_IMM11BY2,     IMAGE_REL_MCORE_PCREL_IMM11BY2);
 266       HOW2MAP (BFD_RELOC_MCORE_PCREL_IMM4BY2,      IMAGE_REL_MCORE_PCREL_IMM4BY2);
 267       HOW2MAP (BFD_RELOC_32_PCREL,                 IMAGE_REL_MCORE_PCREL_32);
 268       HOW2MAP (BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2, IMAGE_REL_MCORE_PCREL_JSR_IMM11BY2);
 269       HOW2MAP (BFD_RELOC_RVA,                      IMAGE_REL_MCORE_RVA);
 270    default:
 271       return NULL;
 272     }
 273   /*NOTREACHED*/
 274 }
 275 #undef HOW2MAP
 276
 277 #define NUM_HOWTOS NUM_ELEM (mcore_coff_howto_table)
 278
 279 static reloc_howto_type *
 280 mcore_coff_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 281                               const char *r_name)
 282 {
 283   unsigned int i;
 284
 285   for (i = 0; i < NUM_HOWTOS; i++)
 286     if (mcore_coff_howto_table[i].name != NULL
 287         && strcasecmp (mcore_coff_howto_table[i].name, r_name) == 0)
 288       return &mcore_coff_howto_table[i];
 289
 290   return NULL;
 291 }
 292
 293 #define RTYPE2HOWTO(cache_ptr, dst)                             \
 294   ((cache_ptr)->howto =                                         \
 295    ((dst)->r_type < NUM_HOWTOS                                  \
 296     ? mcore_coff_howto_table + (dst)->r_type                    \
 297     : NULL))
 298
 299 static reloc_howto_type *
 300 coff_mcore_rtype_to_howto (bfd * abfd ATTRIBUTE_UNUSED,
 301                            asection * sec,
 302                            struct internal_reloc * rel,
 303                            struct coff_link_hash_entry * h ATTRIBUTE_UNUSED,
 304                            struct internal_syment * sym,
 305                            bfd_vma * addendp)
 306 {
 307   reloc_howto_type * howto;
 308
 309   if (rel->r_type >= NUM_HOWTOS)
 310     return NULL;
 311
 312   howto = mcore_coff_howto_table + rel->r_type;
 313
 314   if (rel->r_type == IMAGE_REL_MCORE_RVA)
 315     * addendp -= pe_data (sec->output_section->owner)->pe_opthdr.ImageBase;
 316
 317   else if (howto->pc_relative)
 318     {
 319       * addendp = sec->vma - 2; /* XXX guess - is this right ? */
 320
 321       /* If the symbol is defined, then the generic code is going to
 322          add back the symbol value in order to cancel out an
 323          adjustment it made to the addend.  However, we set the addend
 324          to 0 at the start of this function.  We need to adjust here,
 325          to avoid the adjustment the generic code will make.  FIXME:
 326          This is getting a bit hackish.  */
 327       if (sym != NULL && sym->n_scnum != 0)
 328         * addendp -= sym->n_value;
 329     }
 330   else
 331     * addendp = 0;
 332
 333   return howto;
 334 }
 335
 336 /* Return TRUE if this relocation should appear in the output .reloc section.
 337    This function is referenced in pe_mkobject in peicode.h.  */
 338
 339 static bool
 340 in_reloc_p (bfd * abfd ATTRIBUTE_UNUSED, reloc_howto_type * howto)
 341 {
 342   return ! howto->pc_relative && howto->type != IMAGE_REL_MCORE_RVA;
 343 }
 344 \f
 345 /* The reloc processing routine for the optimized COFF linker.  */
 346 static bool
 347 coff_mcore_relocate_section (bfd * output_bfd,
 348                              struct bfd_link_info * info,
 349                              bfd * input_bfd,
 350                              asection * input_section,
 351                              bfd_byte * contents,
 352                              struct internal_reloc * relocs,
 353                              struct internal_syment * syms,
 354                              asection ** sections)
 355 {
 356   struct internal_reloc * rel;
 357   struct internal_reloc * relend;
 358
 359   /* If we are performing a relocatable link, we don't need to do a
 360      thing.  The caller will take care of adjusting the reloc
 361      addresses and symbol indices.  */
 362   if (bfd_link_relocatable (info))
 363     return true;
 364
 365   /* Check if we have the same endianness */
 366   if (   input_bfd->xvec->byteorder != output_bfd->xvec->byteorder
 367       && output_bfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN)
 368     {
 369       _bfd_error_handler
 370         /* xgettext: c-format */
 371         (_("%pB: compiled for a %s system and target is %s.\n"),
 372          input_bfd,
 373          bfd_big_endian (input_bfd) ? _("big endian") : _("little endian"),
 374          bfd_big_endian (output_bfd) ? _("big endian") : _("little endian"));
 375
 376       bfd_set_error (bfd_error_wrong_format);
 377       return false;
 378     }
 379
 380   rel = relocs;
 381   relend = rel + input_section->reloc_count;
 382
 383   for (; rel < relend; rel++)
 384     {
 385       long                           symndx;
 386       struct internal_syment *       sym;
 387       bfd_vma                        val;
 388       bfd_vma                        addend;
 389       bfd_reloc_status_type          rstat;
 390       bfd_byte *                     loc;
 391       unsigned short                 r_type = rel->r_type;
 392       reloc_howto_type *             howto = NULL;
 393       struct coff_link_hash_entry *  h;
 394       const char *                   my_name;
 395       char buf[SYMNMLEN + 1];
 396
 397       symndx = rel->r_symndx;
 398       loc = contents + rel->r_vaddr - input_section->vma;
 399
 400       if (symndx == -1)
 401         {
 402           h = NULL;
 403           sym = NULL;
 404         }
 405       else
 406         {
 407           h = obj_coff_sym_hashes (input_bfd)[symndx];
 408           sym = syms + symndx;
 409         }
 410
 411       addend = 0;
 412
 413       /* Get the howto and initialise the addend.  */
 414       howto = bfd_coff_rtype_to_howto (input_bfd, input_section, rel, h,
 415                                        sym, & addend);
 416       if (howto == NULL)
 417         return false;
 418
 419       val = 0;
 420
 421       if (h == NULL)
 422         {
 423           if (symndx == -1)
 424             my_name = "*ABS*";
 425           else
 426             {
 427               asection * sec = sections[symndx];
 428
 429               val = (sym->n_value
 430                      + sec->output_section->vma
 431                      + sec->output_offset);
 432
 433               if (sym == NULL)
 434                 my_name = "*unknown*";
 435               else if (   sym->_n._n_n._n_zeroes == 0
 436                        && sym->_n._n_n._n_offset != 0)
 437                 {
 438                   if (sym->_n._n_n._n_offset < obj_coff_strings_len (input_bfd))
 439                     my_name = (obj_coff_strings (input_bfd)
 440                                + sym->_n._n_n._n_offset);
 441                   else
 442                     my_name = "?";
 443                 }
 444               else
 445                 {
 446                   strncpy (buf, sym->_n._n_name, SYMNMLEN);
 447                   buf[SYMNMLEN] = '\0';
 448                   my_name = buf;
 449                 }
 450             }
 451         }
 452       else
 453         {
 454           if (   h->root.type == bfd_link_hash_defined
 455               || h->root.type == bfd_link_hash_defweak)
 456             {
 457               asection * sec = h->root.u.def.section;
 458
 459               val = (h->root.u.def.value
 460                      + sec->output_section->vma
 461                      + sec->output_offset);
 462             }
 463           else
 464             (*info->callbacks->undefined_symbol)
 465               (info, h->root.root.string, input_bfd, input_section,
 466                rel->r_vaddr - input_section->vma, true);
 467
 468           my_name = h->root.root.string;
 469         }
 470
 471       rstat = bfd_reloc_ok;
 472
 473       /* Each case must do its own relocation, setting rstat appropriately.  */
 474       switch (r_type)
 475         {
 476         default:
 477           /* xgettext: c-format */
 478           _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
 479                               input_bfd, r_type);
 480           bfd_set_error (bfd_error_bad_value);
 481           return false;
 482
 483         case IMAGE_REL_MCORE_ABSOLUTE:
 484           _bfd_error_handler
 485             /* xgettext: c-format */
 486             (_("warning: unsupported reloc %s <file %pB, section %pA>\n"
 487                "sym %ld (%s), r_vaddr %" PRId64 " (%#" PRIx64 ")"),
 488              howto->name, input_bfd, input_section,
 489              rel->r_symndx, my_name, (int64_t) rel->r_vaddr,
 490              (uint64_t) rel->r_vaddr);
 491           break;
 492
 493         case IMAGE_REL_MCORE_PCREL_IMM8BY4:
 494         case IMAGE_REL_MCORE_PCREL_IMM11BY2:
 495         case IMAGE_REL_MCORE_PCREL_IMM4BY2:
 496         case IMAGE_REL_MCORE_PCREL_32:
 497         case IMAGE_REL_MCORE_PCREL_JSR_IMM11BY2:
 498         case IMAGE_REL_MCORE_ADDR32:
 499           /* XXX fixme - shouldn't this be like the code for the RVA reloc ? */
 500           rstat = _bfd_relocate_contents (howto, input_bfd, val, loc);
 501           break;
 502
 503         case IMAGE_REL_MCORE_RVA:
 504           rstat = _bfd_final_link_relocate
 505             (howto, input_bfd,
 506              input_section, contents, rel->r_vaddr - input_section->vma,
 507              val, addend);
 508           break;
 509         }
 510
 511       /* Emit a reloc if the backend thinks it needs it.  */
 512       if (info->base_file
 513           && sym
 514           && pe_data (output_bfd)->in_reloc_p (output_bfd, howto)
 515           && !mcore_emit_base_file_entry (info, output_bfd, input_section,
 516                                           rel->r_vaddr))
 517         return false;
 518
 519       switch (rstat)
 520         {
 521         default:
 522           abort ();
 523
 524         case bfd_reloc_ok:
 525           break;
 526
 527         case bfd_reloc_overflow:
 528           (*info->callbacks->reloc_overflow)
 529             (info, (h ? &h->root : NULL), my_name, howto->name,
 530              (bfd_vma) 0, input_bfd,
 531              input_section, rel->r_vaddr - input_section->vma);
 532         }
 533     }
 534
 535   return true;
 536 }
 537 \f
 538 /* Tailor coffcode.h -- macro heaven.  */
 539
 540 /* We use the special COFF backend linker, with our own special touch.  */
 541
 542 #define coff_bfd_reloc_type_lookup   mcore_coff_reloc_type_lookup
 543 #define coff_bfd_reloc_name_lookup mcore_coff_reloc_name_lookup
 544 #define coff_relocate_section        coff_mcore_relocate_section
 545 #define coff_rtype_to_howto          coff_mcore_rtype_to_howto
 546
 547 #define SELECT_RELOC(internal, howto) {internal.r_type = howto->type;}
 548
 549 /* Make sure that the 'r_offset' field is copied properly
 550    so that identical binaries will compare the same.  */
 551 #define SWAP_IN_RELOC_OFFSET         H_GET_32
 552 #define SWAP_OUT_RELOC_OFFSET        H_PUT_32
 553
 554 #define COFF_PAGE_SIZE               0x1000
 555
 556 #include "coffcode.h"
 557 \f
 558 /* Forward declaration to initialise alternative_target field.  */
 559 extern const bfd_target TARGET_LITTLE_SYM;
 560
 561 /* The transfer vectors that lead the outside world to all of the above.  */
 562 CREATE_BIG_COFF_TARGET_VEC (TARGET_BIG_SYM, TARGET_BIG_NAME, D_PAGED,
 563                             (SEC_CODE | SEC_DATA | SEC_DEBUGGING | SEC_READONLY | SEC_LINK_ONCE | SEC_LINK_DUPLICATES),
 564                             0, & TARGET_LITTLE_SYM, COFF_SWAP_TABLE)
 565 CREATE_LITTLE_COFF_TARGET_VEC (TARGET_LITTLE_SYM, TARGET_LITTLE_NAME, D_PAGED,
 566                                (SEC_CODE | SEC_DATA | SEC_DEBUGGING | SEC_READONLY | SEC_LINK_ONCE | SEC_LINK_DUPLICATES),
 567                                0, & TARGET_BIG_SYM, COFF_SWAP_TABLE)