bfd/mipsbsd.c

   1 /* BFD backend for MIPS BSD (a.out) binaries.
   2    Copyright 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
   3    2005, 2007 Free Software Foundation, Inc.
   4    Written by Ralph Campbell.
   5
   6    This file is part of BFD, the Binary File Descriptor library.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23
  24 /* #define ENTRY_CAN_BE_ZERO */
  25 #define N_HEADER_IN_TEXT(x) 1
  26 #define N_SHARED_LIB(x) 0
  27 #define N_TXTADDR(x) \
  28     (N_MAGIC(x) != ZMAGIC ? (x).a_entry :       /* object file or NMAGIC */\
  29             TEXT_START_ADDR + EXEC_BYTES_SIZE   /* no padding */\
  30     )
  31 #define N_DATADDR(x) (N_TXTADDR(x)+N_TXTSIZE(x))
  32 #define TEXT_START_ADDR 4096
  33 #define TARGET_PAGE_SIZE 4096
  34 #define SEGMENT_SIZE TARGET_PAGE_SIZE
  35 #define DEFAULT_ARCH bfd_arch_mips
  36 #define MACHTYPE_OK(mtype) ((mtype) == M_UNKNOWN \
  37                             || (mtype) == M_MIPS1 || (mtype) == M_MIPS2)
  38 #define MY_symbol_leading_char '\0'
  39
  40 /* Do not "beautify" the CONCAT* macro args.  Traditional C will not
  41    remove whitespace added here, and thus will fail to concatenate
  42    the tokens.  */
  43 #define MY(OP) CONCAT2 (mipsbsd_,OP)
  44
  45 #include "sysdep.h"
  46 #include "bfd.h"
  47 #include "libbfd.h"
  48 #include "libaout.h"
  49
  50 #define SET_ARCH_MACH(ABFD, EXEC) \
  51   MY(set_arch_mach) (ABFD, N_MACHTYPE (EXEC)); \
  52   MY(choose_reloc_size) (ABFD);
  53 static void MY(set_arch_mach) PARAMS ((bfd *abfd, unsigned long machtype));
  54 static void MY(choose_reloc_size) PARAMS ((bfd *abfd));
  55
  56 #define MY_write_object_contents MY(write_object_contents)
  57 static bfd_boolean MY(write_object_contents) PARAMS ((bfd *abfd));
  58
  59 /* We can't use MY(x) here because it leads to a recursive call to CONCAT2
  60    when expanded inside JUMP_TABLE.  */
  61 #define MY_bfd_reloc_type_lookup mipsbsd_reloc_type_lookup
  62 #define MY_bfd_reloc_name_lookup mipsbsd_reloc_name_lookup
  63 #define MY_canonicalize_reloc mipsbsd_canonicalize_reloc
  64
  65 #define MY_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
  66 #define MY_bfd_link_add_symbols _bfd_generic_link_add_symbols
  67 #define MY_final_link_callback unused
  68 #define MY_bfd_final_link _bfd_generic_final_link
  69
  70 #define MY_backend_data &MY(backend_data)
  71 #define MY_BFD_TARGET
  72
  73 #include "aout-target.h"
  74
  75 static bfd_reloc_status_type mips_fix_jmp_addr
  76   PARAMS ((bfd *, arelent *, struct bfd_symbol *, PTR, asection *,
  77            bfd *, char **));
  78
  79 long MY(canonicalize_reloc) PARAMS ((bfd *, sec_ptr, arelent **, asymbol **));
  80
  81 static void
  82 MY(set_arch_mach) (abfd, machtype)
  83      bfd *abfd;
  84      unsigned long machtype;
  85 {
  86   enum bfd_architecture arch;
  87   unsigned int machine;
  88
  89   /* Determine the architecture and machine type of the object file.  */
  90   switch (machtype)
  91     {
  92     case M_MIPS1:
  93       arch = bfd_arch_mips;
  94       machine = bfd_mach_mips3000;
  95       break;
  96
  97     case M_MIPS2:
  98       arch = bfd_arch_mips;
  99       machine = bfd_mach_mips4000;
 100       break;
 101
 102     default:
 103       arch = bfd_arch_obscure;
 104       machine = 0;
 105       break;
 106     }
 107
 108   bfd_set_arch_mach (abfd, arch, machine);
 109 }
 110
 111 /* Determine the size of a relocation entry, based on the architecture */
 112 static void
 113 MY (choose_reloc_size) (abfd)
 114      bfd *abfd;
 115 {
 116   switch (bfd_get_arch (abfd))
 117     {
 118     case bfd_arch_sparc:
 119     case bfd_arch_mips:
 120       obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;
 121       break;
 122     default:
 123       obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;
 124       break;
 125     }
 126 }
 127
 128 /* Write an object file in BSD a.out format.
 129   Section contents have already been written.  We write the
 130   file header, symbols, and relocation.  */
 131
 132 static bfd_boolean
 133 MY (write_object_contents) (abfd)
 134      bfd *abfd;
 135 {
 136   struct external_exec exec_bytes;
 137   struct internal_exec *execp = exec_hdr (abfd);
 138
 139   /* Magic number, maestro, please!  */
 140   switch (bfd_get_arch (abfd))
 141     {
 142     case bfd_arch_m68k:
 143       switch (bfd_get_mach (abfd))
 144         {
 145         case bfd_mach_m68010:
 146           N_SET_MACHTYPE (*execp, M_68010);
 147           break;
 148         default:
 149         case bfd_mach_m68020:
 150           N_SET_MACHTYPE (*execp, M_68020);
 151           break;
 152         }
 153       break;
 154     case bfd_arch_sparc:
 155       N_SET_MACHTYPE (*execp, M_SPARC);
 156       break;
 157     case bfd_arch_i386:
 158       N_SET_MACHTYPE (*execp, M_386);
 159       break;
 160     case bfd_arch_mips:
 161       switch (bfd_get_mach (abfd))
 162         {
 163         case bfd_mach_mips4000:
 164         case bfd_mach_mips6000:
 165           N_SET_MACHTYPE (*execp, M_MIPS2);
 166           break;
 167         default:
 168           N_SET_MACHTYPE (*execp, M_MIPS1);
 169           break;
 170         }
 171       break;
 172     default:
 173       N_SET_MACHTYPE (*execp, M_UNKNOWN);
 174     }
 175
 176   MY (choose_reloc_size) (abfd);
 177
 178   WRITE_HEADERS (abfd, execp);
 179
 180   return TRUE;
 181 }
 182
 183 /* MIPS relocation types.  */
 184 #define MIPS_RELOC_32           0
 185 #define MIPS_RELOC_JMP          1
 186 #define MIPS_RELOC_WDISP16      2
 187 #define MIPS_RELOC_HI16         3
 188 #define MIPS_RELOC_HI16_S       4
 189 #define MIPS_RELOC_LO16         5
 190
 191 /* This is only called when performing a BFD_RELOC_MIPS_JMP relocation.
 192    The jump destination address is formed from the upper 4 bits of the
 193    "current" program counter concatenated with the jump instruction's
 194    26 bit field and two trailing zeros.
 195    If the destination address is not in the same segment as the "current"
 196    program counter, then we need to signal an error.  */
 197
 198 static bfd_reloc_status_type
 199 mips_fix_jmp_addr (abfd, reloc_entry, symbol, data, input_section, output_bfd,
 200                    error_message)
 201      bfd *abfd ATTRIBUTE_UNUSED;
 202      arelent *reloc_entry;
 203      struct bfd_symbol *symbol;
 204      PTR data ATTRIBUTE_UNUSED;
 205      asection *input_section;
 206      bfd *output_bfd;
 207      char **error_message ATTRIBUTE_UNUSED;
 208 {
 209   bfd_vma relocation, pc;
 210
 211   /* If this is a partial relocation, just continue.  */
 212   if (output_bfd != (bfd *)NULL)
 213     return bfd_reloc_continue;
 214
 215   /* If this is an undefined symbol, return error */
 216   if (bfd_is_und_section (symbol->section)
 217       && (symbol->flags & BSF_WEAK) == 0)
 218     return bfd_reloc_undefined;
 219
 220   /* Work out which section the relocation is targeted at and the
 221      initial relocation command value.  */
 222   if (bfd_is_com_section (symbol->section))
 223     relocation = 0;
 224   else
 225     relocation = symbol->value;
 226
 227   relocation += symbol->section->output_section->vma;
 228   relocation += symbol->section->output_offset;
 229   relocation += reloc_entry->addend;
 230
 231   pc = input_section->output_section->vma + input_section->output_offset +
 232     reloc_entry->address + 4;
 233
 234   if ((relocation & 0xF0000000) != (pc & 0xF0000000))
 235     return bfd_reloc_overflow;
 236
 237   return bfd_reloc_continue;
 238 }
 239
 240 /* This is only called when performing a BFD_RELOC_HI16_S relocation.
 241    We need to see if bit 15 is set in the result. If it is, we add
 242    0x10000 and continue normally. This will compensate for the sign extension
 243    when the low bits are added at run time.  */
 244
 245 static bfd_reloc_status_type
 246 mips_fix_hi16_s PARAMS ((bfd *, arelent *, asymbol *, PTR,
 247                          asection *, bfd *, char **));
 248
 249 static bfd_reloc_status_type
 250 mips_fix_hi16_s (abfd, reloc_entry, symbol, data, input_section,
 251                  output_bfd, error_message)
 252      bfd *abfd ATTRIBUTE_UNUSED;
 253      arelent *reloc_entry;
 254      asymbol *symbol;
 255      PTR data ATTRIBUTE_UNUSED;
 256      asection *input_section ATTRIBUTE_UNUSED;
 257      bfd *output_bfd;
 258      char **error_message ATTRIBUTE_UNUSED;
 259 {
 260   bfd_vma relocation;
 261
 262   /* If this is a partial relocation, just continue.  */
 263   if (output_bfd != (bfd *)NULL)
 264     return bfd_reloc_continue;
 265
 266   /* If this is an undefined symbol, return error.  */
 267   if (bfd_is_und_section (symbol->section)
 268       && (symbol->flags & BSF_WEAK) == 0)
 269     return bfd_reloc_undefined;
 270
 271   /* Work out which section the relocation is targeted at and the
 272      initial relocation command value.  */
 273   if (bfd_is_com_section (symbol->section))
 274     relocation = 0;
 275   else
 276     relocation = symbol->value;
 277
 278   relocation += symbol->section->output_section->vma;
 279   relocation += symbol->section->output_offset;
 280   relocation += reloc_entry->addend;
 281
 282   if (relocation & 0x8000)
 283     reloc_entry->addend += 0x10000;
 284
 285   return bfd_reloc_continue;
 286 }
 287
 288 static reloc_howto_type mips_howto_table_ext[] = {
 289   {MIPS_RELOC_32,      0, 2, 32, FALSE, 0,  complain_overflow_bitfield, 0,
 290         "32",       FALSE, 0, 0xffffffff, FALSE},
 291   {MIPS_RELOC_JMP,     2, 2, 26, FALSE, 0, complain_overflow_dont,
 292         mips_fix_jmp_addr,
 293         "MIPS_JMP", FALSE, 0, 0x03ffffff, FALSE},
 294   {MIPS_RELOC_WDISP16, 2, 2, 16, TRUE,  0, complain_overflow_signed, 0,
 295         "WDISP16",  FALSE, 0, 0x0000ffff, FALSE},
 296   {MIPS_RELOC_HI16,   16, 2, 16, FALSE, 0, complain_overflow_bitfield, 0,
 297         "HI16",     FALSE, 0, 0x0000ffff, FALSE},
 298   {MIPS_RELOC_HI16_S, 16, 2, 16, FALSE, 0, complain_overflow_bitfield,
 299         mips_fix_hi16_s,
 300         "HI16_S",   FALSE, 0, 0x0000ffff, FALSE},
 301   {MIPS_RELOC_LO16,    0, 2, 16, FALSE, 0, complain_overflow_dont, 0,
 302         "LO16",     FALSE, 0, 0x0000ffff, FALSE},
 303 };
 304
 305 static reloc_howto_type *
 306 MY(reloc_type_lookup) (bfd *abfd, bfd_reloc_code_real_type code)
 307 {
 308
 309   if (bfd_get_arch (abfd) != bfd_arch_mips)
 310     return 0;
 311
 312   switch (code)
 313     {
 314     case BFD_RELOC_CTOR:
 315     case BFD_RELOC_32:
 316       return (&mips_howto_table_ext[MIPS_RELOC_32]);
 317     case BFD_RELOC_MIPS_JMP:
 318       return (&mips_howto_table_ext[MIPS_RELOC_JMP]);
 319     case BFD_RELOC_16_PCREL_S2:
 320       return (&mips_howto_table_ext[MIPS_RELOC_WDISP16]);
 321     case BFD_RELOC_HI16:
 322       return (&mips_howto_table_ext[MIPS_RELOC_HI16]);
 323     case BFD_RELOC_HI16_S:
 324       return (&mips_howto_table_ext[MIPS_RELOC_HI16_S]);
 325     case BFD_RELOC_LO16:
 326       return (&mips_howto_table_ext[MIPS_RELOC_LO16]);
 327     default:
 328       return 0;
 329     }
 330 }
 331
 332 static reloc_howto_type *
 333 MY(reloc_name_lookup) (bfd *abfd ATTRIBUTE_UNUSED,
 334                              const char *r_name)
 335 {
 336   unsigned int i;
 337
 338   for (i = 0;
 339        i < sizeof (mips_howto_table_ext) / sizeof (mips_howto_table_ext[0]);
 340        i++)
 341     if (mips_howto_table_ext[i].name != NULL
 342         && strcasecmp (mips_howto_table_ext[i].name, r_name) == 0)
 343       return &mips_howto_table_ext[i];
 344
 345   return NULL;
 346 }
 347
 348 /* This is just like the standard aoutx.h version but we need to do our
 349    own mapping of external reloc type values to howto entries.  */
 350 long
 351 MY(canonicalize_reloc) (abfd, section, relptr, symbols)
 352       bfd *abfd;
 353       sec_ptr section;
 354       arelent **relptr;
 355       asymbol **symbols;
 356 {
 357   arelent *tblptr = section->relocation;
 358   unsigned int count, c;
 359   extern reloc_howto_type NAME(aout,ext_howto_table)[];
 360
 361   /* If we have already read in the relocation table, return the values.  */
 362   if (section->flags & SEC_CONSTRUCTOR)
 363     {
 364       arelent_chain *chain = section->constructor_chain;
 365
 366       for (count = 0; count < section->reloc_count; count++)
 367         {
 368           *relptr++ = &chain->relent;
 369           chain = chain->next;
 370         }
 371       *relptr = 0;
 372       return section->reloc_count;
 373     }
 374
 375   if (tblptr && section->reloc_count)
 376     {
 377       for (count = 0; count++ < section->reloc_count;)
 378         *relptr++ = tblptr++;
 379       *relptr = 0;
 380       return section->reloc_count;
 381     }
 382
 383   if (!NAME(aout,slurp_reloc_table) (abfd, section, symbols))
 384     return -1;
 385   tblptr = section->relocation;
 386
 387   /* fix up howto entries.  */
 388   for (count = 0; count++ < section->reloc_count;)
 389     {
 390       c = tblptr->howto - NAME(aout,ext_howto_table);
 391       tblptr->howto = &mips_howto_table_ext[c];
 392
 393       *relptr++ = tblptr++;
 394     }
 395   *relptr = 0;
 396   return section->reloc_count;
 397 }
 398
 399 static const struct aout_backend_data MY(backend_data) = {
 400   0,                            /* zmagic contiguous */
 401   1,                            /* text incl header */
 402   0,                            /* entry is text address */
 403   0,                            /* exec_hdr_flags */
 404   TARGET_PAGE_SIZE,                     /* text vma */
 405   MY_set_sizes,
 406   0,                            /* text size includes exec header */
 407   0,                            /* add_dynamic_symbols */
 408   0,                            /* add_one_symbol */
 409   0,                            /* link_dynamic_object */
 410   0,                            /* write_dynamic_symbol */
 411   0,                            /* check_dynamic_reloc */
 412   0                             /* finish_dynamic_link */
 413 };
 414
 415 extern const bfd_target aout_mips_big_vec;
 416
 417 const bfd_target aout_mips_little_vec =
 418   {
 419     "a.out-mips-little",                /* name */
 420     bfd_target_aout_flavour,
 421     BFD_ENDIAN_LITTLE,          /* target byte order (little) */
 422     BFD_ENDIAN_LITTLE,          /* target headers byte order (little) */
 423     (HAS_RELOC | EXEC_P |               /* object flags */
 424      HAS_LINENO | HAS_DEBUG |
 425      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 426     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
 427     MY_symbol_leading_char,
 428     ' ',                                /* ar_pad_char */
 429     15,                         /* ar_max_namelen */
 430     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 431     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 432     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
 433     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 434     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 435     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
 436     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 437      bfd_generic_archive_p, MY_core_file_p},
 438     {bfd_false, MY_mkobject,    /* bfd_set_format */
 439      _bfd_generic_mkarchive, bfd_false},
 440     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 441      _bfd_write_archive_contents, bfd_false},
 442
 443     BFD_JUMP_TABLE_GENERIC (MY),
 444     BFD_JUMP_TABLE_COPY (MY),
 445     BFD_JUMP_TABLE_CORE (MY),
 446     BFD_JUMP_TABLE_ARCHIVE (MY),
 447     BFD_JUMP_TABLE_SYMBOLS (MY),
 448     BFD_JUMP_TABLE_RELOCS (MY),
 449     BFD_JUMP_TABLE_WRITE (MY),
 450     BFD_JUMP_TABLE_LINK (MY),
 451     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 452
 453     & aout_mips_big_vec,
 454
 455     (PTR) MY_backend_data
 456   };
 457
 458 const bfd_target aout_mips_big_vec =
 459   {
 460     "a.out-mips-big",           /* name */
 461     bfd_target_aout_flavour,
 462     BFD_ENDIAN_BIG,             /* target byte order (big) */
 463     BFD_ENDIAN_BIG,             /* target headers byte order (big) */
 464     (HAS_RELOC | EXEC_P |               /* object flags */
 465      HAS_LINENO | HAS_DEBUG |
 466      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 467     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
 468     MY_symbol_leading_char,
 469     ' ',                                /* ar_pad_char */
 470     15,                         /* ar_max_namelen */
 471     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 472     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 473     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
 474     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 475     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 476     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
 477     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 478      bfd_generic_archive_p, MY_core_file_p},
 479     {bfd_false, MY_mkobject,    /* bfd_set_format */
 480      _bfd_generic_mkarchive, bfd_false},
 481     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 482      _bfd_write_archive_contents, bfd_false},
 483
 484     BFD_JUMP_TABLE_GENERIC (MY),
 485     BFD_JUMP_TABLE_COPY (MY),
 486     BFD_JUMP_TABLE_CORE (MY),
 487     BFD_JUMP_TABLE_ARCHIVE (MY),
 488     BFD_JUMP_TABLE_SYMBOLS (MY),
 489     BFD_JUMP_TABLE_RELOCS (MY),
 490     BFD_JUMP_TABLE_WRITE (MY),
 491     BFD_JUMP_TABLE_LINK (MY),
 492     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 493
 494     & aout_mips_little_vec,
 495
 496     (PTR) MY_backend_data
 497   };