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, 2009, 2011 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_TXTADDR(x) \
  27     (N_MAGIC(x) != ZMAGIC ? (x).a_entry :       /* object file or NMAGIC */\
  28             TEXT_START_ADDR + EXEC_BYTES_SIZE   /* no padding */\
  29     )
  30 #define N_DATADDR(x) (N_TXTADDR(x)+N_TXTSIZE(x))
  31 #define TEXT_START_ADDR 4096
  32 #define TARGET_PAGE_SIZE 4096
  33 #define SEGMENT_SIZE TARGET_PAGE_SIZE
  34 #define DEFAULT_ARCH bfd_arch_mips
  35 #define MACHTYPE_OK(mtype) ((mtype) == M_UNKNOWN \
  36                             || (mtype) == M_MIPS1 || (mtype) == M_MIPS2)
  37 #define MY_symbol_leading_char '\0'
  38
  39 /* Do not "beautify" the CONCAT* macro args.  Traditional C will not
  40    remove whitespace added here, and thus will fail to concatenate
  41    the tokens.  */
  42 #define MY(OP) CONCAT2 (mipsbsd_,OP)
  43
  44 #include "sysdep.h"
  45 #include "bfd.h"
  46 #include "libbfd.h"
  47 #include "libaout.h"
  48
  49 #define SET_ARCH_MACH(ABFD, EXEC) \
  50   MY(set_arch_mach) (ABFD, N_MACHTYPE (EXEC)); \
  51   MY(choose_reloc_size) (ABFD);
  52 static void MY(set_arch_mach) PARAMS ((bfd *abfd, unsigned long machtype));
  53 static void MY(choose_reloc_size) PARAMS ((bfd *abfd));
  54
  55 #define MY_write_object_contents MY(write_object_contents)
  56 static bfd_boolean MY(write_object_contents) PARAMS ((bfd *abfd));
  57
  58 /* We can't use MY(x) here because it leads to a recursive call to CONCAT2
  59    when expanded inside JUMP_TABLE.  */
  60 #define MY_bfd_reloc_type_lookup mipsbsd_reloc_type_lookup
  61 #define MY_bfd_reloc_name_lookup mipsbsd_reloc_name_lookup
  62 #define MY_canonicalize_reloc mipsbsd_canonicalize_reloc
  63
  64 #define MY_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
  65 #define MY_bfd_link_add_symbols _bfd_generic_link_add_symbols
  66 #define MY_final_link_callback unused
  67 #define MY_bfd_final_link _bfd_generic_final_link
  68
  69 #define MY_backend_data &MY(backend_data)
  70 #define MY_BFD_TARGET
  71
  72 #include "aout-target.h"
  73
  74 static bfd_reloc_status_type mips_fix_jmp_addr
  75   PARAMS ((bfd *, arelent *, struct bfd_symbol *, PTR, asection *,
  76            bfd *, char **));
  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_type_lookup) (bfd *abfd, bfd_reloc_code_real_type code)
 306 {
 307
 308   if (bfd_get_arch (abfd) != bfd_arch_mips)
 309     return 0;
 310
 311   switch (code)
 312     {
 313     case BFD_RELOC_CTOR:
 314     case BFD_RELOC_32:
 315       return (&mips_howto_table_ext[MIPS_RELOC_32]);
 316     case BFD_RELOC_MIPS_JMP:
 317       return (&mips_howto_table_ext[MIPS_RELOC_JMP]);
 318     case BFD_RELOC_16_PCREL_S2:
 319       return (&mips_howto_table_ext[MIPS_RELOC_WDISP16]);
 320     case BFD_RELOC_HI16:
 321       return (&mips_howto_table_ext[MIPS_RELOC_HI16]);
 322     case BFD_RELOC_HI16_S:
 323       return (&mips_howto_table_ext[MIPS_RELOC_HI16_S]);
 324     case BFD_RELOC_LO16:
 325       return (&mips_howto_table_ext[MIPS_RELOC_LO16]);
 326     default:
 327       return 0;
 328     }
 329 }
 330
 331 static reloc_howto_type *
 332 MY(reloc_name_lookup) (bfd *abfd ATTRIBUTE_UNUSED,
 333                              const char *r_name)
 334 {
 335   unsigned int i;
 336
 337   for (i = 0;
 338        i < sizeof (mips_howto_table_ext) / sizeof (mips_howto_table_ext[0]);
 339        i++)
 340     if (mips_howto_table_ext[i].name != NULL
 341         && strcasecmp (mips_howto_table_ext[i].name, r_name) == 0)
 342       return &mips_howto_table_ext[i];
 343
 344   return NULL;
 345 }
 346
 347 /* This is just like the standard aoutx.h version but we need to do our
 348    own mapping of external reloc type values to howto entries.  */
 349 long
 350 MY(canonicalize_reloc) (abfd, section, relptr, symbols)
 351       bfd *abfd;
 352       sec_ptr section;
 353       arelent **relptr;
 354       asymbol **symbols;
 355 {
 356   arelent *tblptr = section->relocation;
 357   unsigned int count, c;
 358   extern reloc_howto_type NAME(aout,ext_howto_table)[];
 359
 360   /* If we have already read in the relocation table, return the values.  */
 361   if (section->flags & SEC_CONSTRUCTOR)
 362     {
 363       arelent_chain *chain = section->constructor_chain;
 364
 365       for (count = 0; count < section->reloc_count; count++)
 366         {
 367           *relptr++ = &chain->relent;
 368           chain = chain->next;
 369         }
 370       *relptr = 0;
 371       return section->reloc_count;
 372     }
 373
 374   if (tblptr && section->reloc_count)
 375     {
 376       for (count = 0; count++ < section->reloc_count;)
 377         *relptr++ = tblptr++;
 378       *relptr = 0;
 379       return section->reloc_count;
 380     }
 381
 382   if (!NAME(aout,slurp_reloc_table) (abfd, section, symbols))
 383     return -1;
 384   tblptr = section->relocation;
 385
 386   /* fix up howto entries.  */
 387   for (count = 0; count++ < section->reloc_count;)
 388     {
 389       c = tblptr->howto - NAME(aout,ext_howto_table);
 390       tblptr->howto = &mips_howto_table_ext[c];
 391
 392       *relptr++ = tblptr++;
 393     }
 394   *relptr = 0;
 395   return section->reloc_count;
 396 }
 397
 398 static const struct aout_backend_data MY(backend_data) = {
 399   0,                            /* zmagic contiguous */
 400   1,                            /* text incl header */
 401   0,                            /* entry is text address */
 402   0,                            /* exec_hdr_flags */
 403   TARGET_PAGE_SIZE,                     /* text vma */
 404   MY_set_sizes,
 405   0,                            /* text size includes exec header */
 406   0,                            /* add_dynamic_symbols */
 407   0,                            /* add_one_symbol */
 408   0,                            /* link_dynamic_object */
 409   0,                            /* write_dynamic_symbol */
 410   0,                            /* check_dynamic_reloc */
 411   0                             /* finish_dynamic_link */
 412 };
 413
 414 extern const bfd_target aout_mips_big_vec;
 415
 416 const bfd_target aout_mips_little_vec =
 417   {
 418     "a.out-mips-little",                /* name */
 419     bfd_target_aout_flavour,
 420     BFD_ENDIAN_LITTLE,          /* target byte order (little) */
 421     BFD_ENDIAN_LITTLE,          /* target headers byte order (little) */
 422     (HAS_RELOC | EXEC_P |               /* object flags */
 423      HAS_LINENO | HAS_DEBUG |
 424      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 425     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
 426     MY_symbol_leading_char,
 427     ' ',                                /* ar_pad_char */
 428     15,                         /* ar_max_namelen */
 429     0,                          /* match priority.  */
 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     0,                          /* match priority.  */
 472     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 473     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 474     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
 475     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 476     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 477     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
 478     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 479      bfd_generic_archive_p, MY_core_file_p},
 480     {bfd_false, MY_mkobject,    /* bfd_set_format */
 481      _bfd_generic_mkarchive, bfd_false},
 482     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 483      _bfd_write_archive_contents, bfd_false},
 484
 485     BFD_JUMP_TABLE_GENERIC (MY),
 486     BFD_JUMP_TABLE_COPY (MY),
 487     BFD_JUMP_TABLE_CORE (MY),
 488     BFD_JUMP_TABLE_ARCHIVE (MY),
 489     BFD_JUMP_TABLE_SYMBOLS (MY),
 490     BFD_JUMP_TABLE_RELOCS (MY),
 491     BFD_JUMP_TABLE_WRITE (MY),
 492     BFD_JUMP_TABLE_LINK (MY),
 493     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 494
 495     & aout_mips_little_vec,
 496
 497     (PTR) MY_backend_data
 498   };