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