bfd/mipsbsd.c

   1 /* BFD backend for MIPS BSD (a.out) binaries.
   2    Copyright 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2001
   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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #define BYTES_IN_WORD 4
  23 /* #define ENTRY_CAN_BE_ZERO */
  24 #define N_HEADER_IN_TEXT(x) 1
  25 #define N_SHARED_LIB(x) 0
  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 #define MY(OP) CAT(mipsbsd_,OP)
  40
  41 #include "bfd.h"
  42 #include "sysdep.h"
  43 #include "libbfd.h"
  44 #include "libaout.h"
  45
  46 #define SET_ARCH_MACH(ABFD, EXEC) \
  47   MY(set_arch_mach) (ABFD, N_MACHTYPE (EXEC)); \
  48   MY(choose_reloc_size) (ABFD);
  49 static void MY(set_arch_mach) PARAMS ((bfd *abfd, unsigned long machtype));
  50 static void MY(choose_reloc_size) PARAMS ((bfd *abfd));
  51
  52 #define MY_write_object_contents MY(write_object_contents)
  53 static boolean MY(write_object_contents) PARAMS ((bfd *abfd));
  54
  55 /* We can't use MY(x) here because it leads to a recursive call to CAT
  56    when expanded inside JUMP_TABLE.  */
  57 #define MY_bfd_reloc_type_lookup mipsbsd_reloc_howto_type_lookup
  58 #define MY_canonicalize_reloc mipsbsd_canonicalize_reloc
  59
  60 #define MY_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
  61 #define MY_bfd_link_add_symbols _bfd_generic_link_add_symbols
  62 #define MY_final_link_callback unused
  63 #define MY_bfd_final_link _bfd_generic_final_link
  64
  65 #define MY_backend_data &MY(backend_data)
  66 #define MY_BFD_TARGET
  67
  68 #include "aout-target.h"
  69
  70 static bfd_reloc_status_type mips_fix_jmp_addr
  71   PARAMS ((bfd *, arelent *, struct symbol_cache_entry *, PTR, asection *,
  72            bfd *, char **));
  73 static reloc_howto_type *MY(reloc_howto_type_lookup)
  74   PARAMS ((bfd *, bfd_reloc_code_real_type));
  75
  76 long MY(canonicalize_reloc) PARAMS ((bfd *, sec_ptr, arelent **, asymbol **));
  77
  78 static void
  79 MY(set_arch_mach) (abfd, machtype)
  80      bfd *abfd;
  81      unsigned long machtype;
  82 {
  83   enum bfd_architecture arch;
  84   unsigned int machine;
  85
  86   /* Determine the architecture and machine type of the object file.  */
  87   switch (machtype)
  88     {
  89     case M_MIPS1:
  90       arch = bfd_arch_mips;
  91       machine = 3000;
  92       break;
  93
  94     case M_MIPS2:
  95       arch = bfd_arch_mips;
  96       machine = 4000;
  97       break;
  98
  99     default:
 100       arch = bfd_arch_obscure;
 101       machine = 0;
 102       break;
 103     }
 104
 105   bfd_set_arch_mach (abfd, arch, machine);
 106 }
 107
 108 /* Determine the size of a relocation entry, based on the architecture */
 109 static void
 110 MY (choose_reloc_size) (abfd)
 111      bfd *abfd;
 112 {
 113   switch (bfd_get_arch (abfd))
 114     {
 115     case bfd_arch_sparc:
 116     case bfd_arch_a29k:
 117     case bfd_arch_mips:
 118       obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;
 119       break;
 120     default:
 121       obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;
 122       break;
 123     }
 124 }
 125
 126 /* Write an object file in BSD a.out format.
 127   Section contents have already been written.  We write the
 128   file header, symbols, and relocation.  */
 129
 130 static boolean
 131 MY (write_object_contents) (abfd)
 132      bfd *abfd;
 133 {
 134   struct external_exec exec_bytes;
 135   struct internal_exec *execp = exec_hdr (abfd);
 136
 137   /* Magic number, maestro, please!  */
 138   switch (bfd_get_arch (abfd))
 139     {
 140     case bfd_arch_m68k:
 141       switch (bfd_get_mach (abfd))
 142         {
 143         case bfd_mach_m68010:
 144           N_SET_MACHTYPE (*execp, M_68010);
 145           break;
 146         default:
 147         case bfd_mach_m68020:
 148           N_SET_MACHTYPE (*execp, M_68020);
 149           break;
 150         }
 151       break;
 152     case bfd_arch_sparc:
 153       N_SET_MACHTYPE (*execp, M_SPARC);
 154       break;
 155     case bfd_arch_i386:
 156       N_SET_MACHTYPE (*execp, M_386);
 157       break;
 158     case bfd_arch_a29k:
 159       N_SET_MACHTYPE (*execp, M_29K);
 160       break;
 161     case bfd_arch_mips:
 162       switch (bfd_get_mach (abfd))
 163         {
 164         case 4000:
 165         case 6000:
 166           N_SET_MACHTYPE (*execp, M_MIPS2);
 167           break;
 168         default:
 169           N_SET_MACHTYPE (*execp, M_MIPS1);
 170           break;
 171         }
 172       break;
 173     default:
 174       N_SET_MACHTYPE (*execp, M_UNKNOWN);
 175     }
 176
 177   MY (choose_reloc_size) (abfd);
 178
 179   WRITE_HEADERS (abfd, execp);
 180
 181   return true;
 182 }
 183
 184 /* MIPS relocation types.  */
 185 #define MIPS_RELOC_32           0
 186 #define MIPS_RELOC_JMP          1
 187 #define MIPS_RELOC_WDISP16      2
 188 #define MIPS_RELOC_HI16         3
 189 #define MIPS_RELOC_HI16_S       4
 190 #define MIPS_RELOC_LO16         5
 191
 192 /* This is only called when performing a BFD_RELOC_MIPS_JMP relocation.
 193    The jump destination address is formed from the upper 4 bits of the
 194    "current" program counter concatenated with the jump instruction's
 195    26 bit field and two trailing zeros.
 196    If the destination address is not in the same segment as the "current"
 197    program counter, then we need to signal an error.  */
 198
 199 static bfd_reloc_status_type
 200 mips_fix_jmp_addr (abfd, reloc_entry, symbol, data, input_section, output_bfd,
 201                    error_message)
 202      bfd *abfd ATTRIBUTE_UNUSED;
 203      arelent *reloc_entry;
 204      struct symbol_cache_entry *symbol;
 205      PTR data ATTRIBUTE_UNUSED;
 206      asection *input_section;
 207      bfd *output_bfd;
 208      char **error_message ATTRIBUTE_UNUSED;
 209 {
 210   bfd_vma relocation, pc;
 211
 212   /* If this is a partial relocation, just continue.  */
 213   if (output_bfd != (bfd *)NULL)
 214     return bfd_reloc_continue;
 215
 216   /* If this is an undefined symbol, return error */
 217   if (bfd_is_und_section (symbol->section)
 218       && (symbol->flags & BSF_WEAK) == 0)
 219     return bfd_reloc_undefined;
 220
 221   /* Work out which section the relocation is targetted at and the
 222      initial relocation command value.  */
 223   if (bfd_is_com_section (symbol->section))
 224     relocation = 0;
 225   else
 226     relocation = symbol->value;
 227
 228   relocation += symbol->section->output_section->vma;
 229   relocation += symbol->section->output_offset;
 230   relocation += reloc_entry->addend;
 231
 232   pc = input_section->output_section->vma + input_section->output_offset +
 233     reloc_entry->address + 4;
 234
 235   if ((relocation & 0xF0000000) != (pc & 0xF0000000))
 236     return bfd_reloc_overflow;
 237
 238   return bfd_reloc_continue;
 239 }
 240
 241 /* This is only called when performing a BFD_RELOC_HI16_S relocation.
 242    We need to see if bit 15 is set in the result. If it is, we add
 243    0x10000 and continue normally. This will compensate for the sign extension
 244    when the low bits are added at run time.  */
 245
 246 static bfd_reloc_status_type
 247 mips_fix_hi16_s PARAMS ((bfd *, arelent *, asymbol *, PTR,
 248                          asection *, bfd *, char **));
 249
 250 static bfd_reloc_status_type
 251 mips_fix_hi16_s (abfd, reloc_entry, symbol, data, input_section,
 252                  output_bfd, error_message)
 253      bfd *abfd ATTRIBUTE_UNUSED;
 254      arelent *reloc_entry;
 255      asymbol *symbol;
 256      PTR data ATTRIBUTE_UNUSED;
 257      asection *input_section ATTRIBUTE_UNUSED;
 258      bfd *output_bfd;
 259      char **error_message ATTRIBUTE_UNUSED;
 260 {
 261   bfd_vma relocation;
 262
 263   /* If this is a partial relocation, just continue.  */
 264   if (output_bfd != (bfd *)NULL)
 265     return bfd_reloc_continue;
 266
 267   /* If this is an undefined symbol, return error.  */
 268   if (bfd_is_und_section (symbol->section)
 269       && (symbol->flags & BSF_WEAK) == 0)
 270     return bfd_reloc_undefined;
 271
 272   /* Work out which section the relocation is targetted at and the
 273      initial relocation command value.  */
 274   if (bfd_is_com_section (symbol->section))
 275     relocation = 0;
 276   else
 277     relocation = symbol->value;
 278
 279   relocation += symbol->section->output_section->vma;
 280   relocation += symbol->section->output_offset;
 281   relocation += reloc_entry->addend;
 282
 283   if (relocation & 0x8000)
 284     reloc_entry->addend += 0x10000;
 285
 286   return bfd_reloc_continue;
 287 }
 288
 289 static reloc_howto_type mips_howto_table_ext[] = {
 290   {MIPS_RELOC_32,      0, 2, 32, false, 0,  complain_overflow_bitfield, 0,
 291         "32",       false, 0, 0xffffffff, false},
 292   {MIPS_RELOC_JMP,     2, 2, 26, false, 0, complain_overflow_dont,
 293         mips_fix_jmp_addr,
 294         "MIPS_JMP", false, 0, 0x03ffffff, false},
 295   {MIPS_RELOC_WDISP16, 2, 2, 16, true,  0, complain_overflow_signed, 0,
 296         "WDISP16",  false, 0, 0x0000ffff, false},
 297   {MIPS_RELOC_HI16,   16, 2, 16, false, 0, complain_overflow_bitfield, 0,
 298         "HI16",     false, 0, 0x0000ffff, false},
 299   {MIPS_RELOC_HI16_S, 16, 2, 16, false, 0, complain_overflow_bitfield,
 300         mips_fix_hi16_s,
 301         "HI16_S",   false, 0, 0x0000ffff, false},
 302   {MIPS_RELOC_LO16,    0, 2, 16, false, 0, complain_overflow_dont, 0,
 303         "LO16",     false, 0, 0x0000ffff, false},
 304 };
 305
 306 static reloc_howto_type *
 307 MY(reloc_howto_type_lookup) (abfd, code)
 308      bfd *abfd;
 309      bfd_reloc_code_real_type code;
 310 {
 311
 312   if (bfd_get_arch (abfd) != bfd_arch_mips)
 313     return 0;
 314
 315   switch (code)
 316     {
 317     case BFD_RELOC_CTOR:
 318     case BFD_RELOC_32:
 319       return (&mips_howto_table_ext[MIPS_RELOC_32]);
 320     case BFD_RELOC_MIPS_JMP:
 321       return (&mips_howto_table_ext[MIPS_RELOC_JMP]);
 322     case BFD_RELOC_16_PCREL_S2:
 323       return (&mips_howto_table_ext[MIPS_RELOC_WDISP16]);
 324     case BFD_RELOC_HI16:
 325       return (&mips_howto_table_ext[MIPS_RELOC_HI16]);
 326     case BFD_RELOC_HI16_S:
 327       return (&mips_howto_table_ext[MIPS_RELOC_HI16_S]);
 328     case BFD_RELOC_LO16:
 329       return (&mips_howto_table_ext[MIPS_RELOC_LO16]);
 330     default:
 331       return 0;
 332     }
 333 }
 334
 335 /* This is just like the standard aoutx.h version but we need to do our
 336    own mapping of external reloc type values to howto entries.  */
 337 long
 338 MY(canonicalize_reloc) (abfd, section, relptr, symbols)
 339       bfd *abfd;
 340       sec_ptr section;
 341       arelent **relptr;
 342       asymbol **symbols;
 343 {
 344   arelent *tblptr = section->relocation;
 345   unsigned int count, c;
 346   extern reloc_howto_type NAME(aout,ext_howto_table)[];
 347
 348   /* If we have already read in the relocation table, return the values.  */
 349   if (section->flags & SEC_CONSTRUCTOR)
 350     {
 351       arelent_chain *chain = section->constructor_chain;
 352
 353       for (count = 0; count < section->reloc_count; count++)
 354         {
 355           *relptr++ = &chain->relent;
 356           chain = chain->next;
 357         }
 358       *relptr = 0;
 359       return section->reloc_count;
 360     }
 361
 362   if (tblptr && section->reloc_count)
 363     {
 364       for (count = 0; count++ < section->reloc_count;)
 365         *relptr++ = tblptr++;
 366       *relptr = 0;
 367       return section->reloc_count;
 368     }
 369
 370   if (!NAME(aout,slurp_reloc_table) (abfd, section, symbols))
 371     return -1;
 372   tblptr = section->relocation;
 373
 374   /* fix up howto entries.  */
 375   for (count = 0; count++ < section->reloc_count;)
 376     {
 377       c = tblptr->howto - NAME(aout,ext_howto_table);
 378       tblptr->howto = &mips_howto_table_ext[c];
 379
 380       *relptr++ = tblptr++;
 381     }
 382   *relptr = 0;
 383   return section->reloc_count;
 384 }
 385
 386 static const struct aout_backend_data MY(backend_data) = {
 387   0,                            /* zmagic contiguous */
 388   1,                            /* text incl header */
 389   0,                            /* entry is text address */
 390   0,                            /* exec_hdr_flags */
 391   TARGET_PAGE_SIZE,                     /* text vma */
 392   MY_set_sizes,
 393   0,                            /* text size includes exec header */
 394   0,                            /* add_dynamic_symbols */
 395   0,                            /* add_one_symbol */
 396   0,                            /* link_dynamic_object */
 397   0,                            /* write_dynamic_symbol */
 398   0,                            /* check_dynamic_reloc */
 399   0                             /* finish_dynamic_link */
 400 };
 401
 402 extern const bfd_target aout_mips_big_vec;
 403
 404 const bfd_target aout_mips_little_vec =
 405   {
 406     "a.out-mips-little",                /* name */
 407     bfd_target_aout_flavour,
 408     BFD_ENDIAN_LITTLE,          /* target byte order (little) */
 409     BFD_ENDIAN_LITTLE,          /* target headers byte order (little) */
 410     (HAS_RELOC | EXEC_P |               /* object flags */
 411      HAS_LINENO | HAS_DEBUG |
 412      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 413     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
 414     MY_symbol_leading_char,
 415     ' ',                                /* ar_pad_char */
 416     15,                         /* ar_max_namelen */
 417     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 418     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 419     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
 420     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 421     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 422     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
 423     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 424      bfd_generic_archive_p, MY_core_file_p},
 425     {bfd_false, MY_mkobject,    /* bfd_set_format */
 426      _bfd_generic_mkarchive, bfd_false},
 427     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 428      _bfd_write_archive_contents, bfd_false},
 429
 430     BFD_JUMP_TABLE_GENERIC (MY),
 431     BFD_JUMP_TABLE_COPY (MY),
 432     BFD_JUMP_TABLE_CORE (MY),
 433     BFD_JUMP_TABLE_ARCHIVE (MY),
 434     BFD_JUMP_TABLE_SYMBOLS (MY),
 435     BFD_JUMP_TABLE_RELOCS (MY),
 436     BFD_JUMP_TABLE_WRITE (MY),
 437     BFD_JUMP_TABLE_LINK (MY),
 438     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 439
 440     & aout_mips_big_vec,
 441
 442     (PTR) MY_backend_data
 443   };
 444
 445 const bfd_target aout_mips_big_vec =
 446   {
 447     "a.out-mips-big",           /* name */
 448     bfd_target_aout_flavour,
 449     BFD_ENDIAN_BIG,             /* target byte order (big) */
 450     BFD_ENDIAN_BIG,             /* target headers byte order (big) */
 451     (HAS_RELOC | EXEC_P |               /* object flags */
 452      HAS_LINENO | HAS_DEBUG |
 453      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 454     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
 455     MY_symbol_leading_char,
 456     ' ',                                /* ar_pad_char */
 457     15,                         /* ar_max_namelen */
 458     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 459     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 460     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
 461     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 462     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 463     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
 464     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 465      bfd_generic_archive_p, MY_core_file_p},
 466     {bfd_false, MY_mkobject,    /* bfd_set_format */
 467      _bfd_generic_mkarchive, bfd_false},
 468     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 469      _bfd_write_archive_contents, bfd_false},
 470
 471     BFD_JUMP_TABLE_GENERIC (MY),
 472     BFD_JUMP_TABLE_COPY (MY),
 473     BFD_JUMP_TABLE_CORE (MY),
 474     BFD_JUMP_TABLE_ARCHIVE (MY),
 475     BFD_JUMP_TABLE_SYMBOLS (MY),
 476     BFD_JUMP_TABLE_RELOCS (MY),
 477     BFD_JUMP_TABLE_WRITE (MY),
 478     BFD_JUMP_TABLE_LINK (MY),
 479     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 480
 481     & aout_mips_little_vec,
 482
 483     (PTR) MY_backend_data
 484   };