bfd/mipsbsd.c

   1 /* BFD backend for MIPS BSD (a.out) binaries.
   2    Copyright 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2001, 2002
   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 /* 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 "bfd.h"
  45 #include "sysdep.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 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_howto_type_lookup
  61 #define MY_canonicalize_reloc mipsbsd_canonicalize_reloc
  62
  63 #define MY_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
  64 #define MY_bfd_link_add_symbols _bfd_generic_link_add_symbols
  65 #define MY_final_link_callback unused
  66 #define MY_bfd_final_link _bfd_generic_final_link
  67
  68 #define MY_backend_data &MY(backend_data)
  69 #define MY_BFD_TARGET
  70
  71 #include "aout-target.h"
  72
  73 static bfd_reloc_status_type mips_fix_jmp_addr
  74   PARAMS ((bfd *, arelent *, struct symbol_cache_entry *, PTR, asection *,
  75            bfd *, char **));
  76 static reloc_howto_type *MY(reloc_howto_type_lookup)
  77   PARAMS ((bfd *, bfd_reloc_code_real_type));
  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_a29k:
 120     case bfd_arch_mips:
 121       obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;
 122       break;
 123     default:
 124       obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;
 125       break;
 126     }
 127 }
 128
 129 /* Write an object file in BSD a.out format.
 130   Section contents have already been written.  We write the
 131   file header, symbols, and relocation.  */
 132
 133 static boolean
 134 MY (write_object_contents) (abfd)
 135      bfd *abfd;
 136 {
 137   struct external_exec exec_bytes;
 138   struct internal_exec *execp = exec_hdr (abfd);
 139
 140   /* Magic number, maestro, please!  */
 141   switch (bfd_get_arch (abfd))
 142     {
 143     case bfd_arch_m68k:
 144       switch (bfd_get_mach (abfd))
 145         {
 146         case bfd_mach_m68010:
 147           N_SET_MACHTYPE (*execp, M_68010);
 148           break;
 149         default:
 150         case bfd_mach_m68020:
 151           N_SET_MACHTYPE (*execp, M_68020);
 152           break;
 153         }
 154       break;
 155     case bfd_arch_sparc:
 156       N_SET_MACHTYPE (*execp, M_SPARC);
 157       break;
 158     case bfd_arch_i386:
 159       N_SET_MACHTYPE (*execp, M_386);
 160       break;
 161     case bfd_arch_a29k:
 162       N_SET_MACHTYPE (*execp, M_29K);
 163       break;
 164     case bfd_arch_mips:
 165       switch (bfd_get_mach (abfd))
 166         {
 167         case bfd_mach_mips4000:
 168         case bfd_mach_mips6000:
 169           N_SET_MACHTYPE (*execp, M_MIPS2);
 170           break;
 171         default:
 172           N_SET_MACHTYPE (*execp, M_MIPS1);
 173           break;
 174         }
 175       break;
 176     default:
 177       N_SET_MACHTYPE (*execp, M_UNKNOWN);
 178     }
 179
 180   MY (choose_reloc_size) (abfd);
 181
 182   WRITE_HEADERS (abfd, execp);
 183
 184   return true;
 185 }
 186
 187 /* MIPS relocation types.  */
 188 #define MIPS_RELOC_32           0
 189 #define MIPS_RELOC_JMP          1
 190 #define MIPS_RELOC_WDISP16      2
 191 #define MIPS_RELOC_HI16         3
 192 #define MIPS_RELOC_HI16_S       4
 193 #define MIPS_RELOC_LO16         5
 194
 195 /* This is only called when performing a BFD_RELOC_MIPS_JMP relocation.
 196    The jump destination address is formed from the upper 4 bits of the
 197    "current" program counter concatenated with the jump instruction's
 198    26 bit field and two trailing zeros.
 199    If the destination address is not in the same segment as the "current"
 200    program counter, then we need to signal an error.  */
 201
 202 static bfd_reloc_status_type
 203 mips_fix_jmp_addr (abfd, reloc_entry, symbol, data, input_section, output_bfd,
 204                    error_message)
 205      bfd *abfd ATTRIBUTE_UNUSED;
 206      arelent *reloc_entry;
 207      struct symbol_cache_entry *symbol;
 208      PTR data ATTRIBUTE_UNUSED;
 209      asection *input_section;
 210      bfd *output_bfd;
 211      char **error_message ATTRIBUTE_UNUSED;
 212 {
 213   bfd_vma relocation, pc;
 214
 215   /* If this is a partial relocation, just continue.  */
 216   if (output_bfd != (bfd *)NULL)
 217     return bfd_reloc_continue;
 218
 219   /* If this is an undefined symbol, return error */
 220   if (bfd_is_und_section (symbol->section)
 221       && (symbol->flags & BSF_WEAK) == 0)
 222     return bfd_reloc_undefined;
 223
 224   /* Work out which section the relocation is targetted at and the
 225      initial relocation command value.  */
 226   if (bfd_is_com_section (symbol->section))
 227     relocation = 0;
 228   else
 229     relocation = symbol->value;
 230
 231   relocation += symbol->section->output_section->vma;
 232   relocation += symbol->section->output_offset;
 233   relocation += reloc_entry->addend;
 234
 235   pc = input_section->output_section->vma + input_section->output_offset +
 236     reloc_entry->address + 4;
 237
 238   if ((relocation & 0xF0000000) != (pc & 0xF0000000))
 239     return bfd_reloc_overflow;
 240
 241   return bfd_reloc_continue;
 242 }
 243
 244 /* This is only called when performing a BFD_RELOC_HI16_S relocation.
 245    We need to see if bit 15 is set in the result. If it is, we add
 246    0x10000 and continue normally. This will compensate for the sign extension
 247    when the low bits are added at run time.  */
 248
 249 static bfd_reloc_status_type
 250 mips_fix_hi16_s PARAMS ((bfd *, arelent *, asymbol *, PTR,
 251                          asection *, bfd *, char **));
 252
 253 static bfd_reloc_status_type
 254 mips_fix_hi16_s (abfd, reloc_entry, symbol, data, input_section,
 255                  output_bfd, error_message)
 256      bfd *abfd ATTRIBUTE_UNUSED;
 257      arelent *reloc_entry;
 258      asymbol *symbol;
 259      PTR data ATTRIBUTE_UNUSED;
 260      asection *input_section ATTRIBUTE_UNUSED;
 261      bfd *output_bfd;
 262      char **error_message ATTRIBUTE_UNUSED;
 263 {
 264   bfd_vma relocation;
 265
 266   /* If this is a partial relocation, just continue.  */
 267   if (output_bfd != (bfd *)NULL)
 268     return bfd_reloc_continue;
 269
 270   /* If this is an undefined symbol, return error.  */
 271   if (bfd_is_und_section (symbol->section)
 272       && (symbol->flags & BSF_WEAK) == 0)
 273     return bfd_reloc_undefined;
 274
 275   /* Work out which section the relocation is targetted at and the
 276      initial relocation command value.  */
 277   if (bfd_is_com_section (symbol->section))
 278     relocation = 0;
 279   else
 280     relocation = symbol->value;
 281
 282   relocation += symbol->section->output_section->vma;
 283   relocation += symbol->section->output_offset;
 284   relocation += reloc_entry->addend;
 285
 286   if (relocation & 0x8000)
 287     reloc_entry->addend += 0x10000;
 288
 289   return bfd_reloc_continue;
 290 }
 291
 292 static reloc_howto_type mips_howto_table_ext[] = {
 293   {MIPS_RELOC_32,      0, 2, 32, false, 0,  complain_overflow_bitfield, 0,
 294         "32",       false, 0, 0xffffffff, false},
 295   {MIPS_RELOC_JMP,     2, 2, 26, false, 0, complain_overflow_dont,
 296         mips_fix_jmp_addr,
 297         "MIPS_JMP", false, 0, 0x03ffffff, false},
 298   {MIPS_RELOC_WDISP16, 2, 2, 16, true,  0, complain_overflow_signed, 0,
 299         "WDISP16",  false, 0, 0x0000ffff, false},
 300   {MIPS_RELOC_HI16,   16, 2, 16, false, 0, complain_overflow_bitfield, 0,
 301         "HI16",     false, 0, 0x0000ffff, false},
 302   {MIPS_RELOC_HI16_S, 16, 2, 16, false, 0, complain_overflow_bitfield,
 303         mips_fix_hi16_s,
 304         "HI16_S",   false, 0, 0x0000ffff, false},
 305   {MIPS_RELOC_LO16,    0, 2, 16, false, 0, complain_overflow_dont, 0,
 306         "LO16",     false, 0, 0x0000ffff, false},
 307 };
 308
 309 static reloc_howto_type *
 310 MY(reloc_howto_type_lookup) (abfd, code)
 311      bfd *abfd;
 312      bfd_reloc_code_real_type code;
 313 {
 314
 315   if (bfd_get_arch (abfd) != bfd_arch_mips)
 316     return 0;
 317
 318   switch (code)
 319     {
 320     case BFD_RELOC_CTOR:
 321     case BFD_RELOC_32:
 322       return (&mips_howto_table_ext[MIPS_RELOC_32]);
 323     case BFD_RELOC_MIPS_JMP:
 324       return (&mips_howto_table_ext[MIPS_RELOC_JMP]);
 325     case BFD_RELOC_16_PCREL_S2:
 326       return (&mips_howto_table_ext[MIPS_RELOC_WDISP16]);
 327     case BFD_RELOC_HI16:
 328       return (&mips_howto_table_ext[MIPS_RELOC_HI16]);
 329     case BFD_RELOC_HI16_S:
 330       return (&mips_howto_table_ext[MIPS_RELOC_HI16_S]);
 331     case BFD_RELOC_LO16:
 332       return (&mips_howto_table_ext[MIPS_RELOC_LO16]);
 333     default:
 334       return 0;
 335     }
 336 }
 337
 338 /* This is just like the standard aoutx.h version but we need to do our
 339    own mapping of external reloc type values to howto entries.  */
 340 long
 341 MY(canonicalize_reloc) (abfd, section, relptr, symbols)
 342       bfd *abfd;
 343       sec_ptr section;
 344       arelent **relptr;
 345       asymbol **symbols;
 346 {
 347   arelent *tblptr = section->relocation;
 348   unsigned int count, c;
 349   extern reloc_howto_type NAME(aout,ext_howto_table)[];
 350
 351   /* If we have already read in the relocation table, return the values.  */
 352   if (section->flags & SEC_CONSTRUCTOR)
 353     {
 354       arelent_chain *chain = section->constructor_chain;
 355
 356       for (count = 0; count < section->reloc_count; count++)
 357         {
 358           *relptr++ = &chain->relent;
 359           chain = chain->next;
 360         }
 361       *relptr = 0;
 362       return section->reloc_count;
 363     }
 364
 365   if (tblptr && section->reloc_count)
 366     {
 367       for (count = 0; count++ < section->reloc_count;)
 368         *relptr++ = tblptr++;
 369       *relptr = 0;
 370       return section->reloc_count;
 371     }
 372
 373   if (!NAME(aout,slurp_reloc_table) (abfd, section, symbols))
 374     return -1;
 375   tblptr = section->relocation;
 376
 377   /* fix up howto entries.  */
 378   for (count = 0; count++ < section->reloc_count;)
 379     {
 380       c = tblptr->howto - NAME(aout,ext_howto_table);
 381       tblptr->howto = &mips_howto_table_ext[c];
 382
 383       *relptr++ = tblptr++;
 384     }
 385   *relptr = 0;
 386   return section->reloc_count;
 387 }
 388
 389 static const struct aout_backend_data MY(backend_data) = {
 390   0,                            /* zmagic contiguous */
 391   1,                            /* text incl header */
 392   0,                            /* entry is text address */
 393   0,                            /* exec_hdr_flags */
 394   TARGET_PAGE_SIZE,                     /* text vma */
 395   MY_set_sizes,
 396   0,                            /* text size includes exec header */
 397   0,                            /* add_dynamic_symbols */
 398   0,                            /* add_one_symbol */
 399   0,                            /* link_dynamic_object */
 400   0,                            /* write_dynamic_symbol */
 401   0,                            /* check_dynamic_reloc */
 402   0                             /* finish_dynamic_link */
 403 };
 404
 405 extern const bfd_target aout_mips_big_vec;
 406
 407 const bfd_target aout_mips_little_vec =
 408   {
 409     "a.out-mips-little",                /* name */
 410     bfd_target_aout_flavour,
 411     BFD_ENDIAN_LITTLE,          /* target byte order (little) */
 412     BFD_ENDIAN_LITTLE,          /* target headers byte order (little) */
 413     (HAS_RELOC | EXEC_P |               /* object flags */
 414      HAS_LINENO | HAS_DEBUG |
 415      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 416     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
 417     MY_symbol_leading_char,
 418     ' ',                                /* ar_pad_char */
 419     15,                         /* ar_max_namelen */
 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, /* data */
 423     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 424     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 425     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
 426     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 427      bfd_generic_archive_p, MY_core_file_p},
 428     {bfd_false, MY_mkobject,    /* bfd_set_format */
 429      _bfd_generic_mkarchive, bfd_false},
 430     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 431      _bfd_write_archive_contents, bfd_false},
 432
 433     BFD_JUMP_TABLE_GENERIC (MY),
 434     BFD_JUMP_TABLE_COPY (MY),
 435     BFD_JUMP_TABLE_CORE (MY),
 436     BFD_JUMP_TABLE_ARCHIVE (MY),
 437     BFD_JUMP_TABLE_SYMBOLS (MY),
 438     BFD_JUMP_TABLE_RELOCS (MY),
 439     BFD_JUMP_TABLE_WRITE (MY),
 440     BFD_JUMP_TABLE_LINK (MY),
 441     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 442
 443     & aout_mips_big_vec,
 444
 445     (PTR) MY_backend_data
 446   };
 447
 448 const bfd_target aout_mips_big_vec =
 449   {
 450     "a.out-mips-big",           /* name */
 451     bfd_target_aout_flavour,
 452     BFD_ENDIAN_BIG,             /* target byte order (big) */
 453     BFD_ENDIAN_BIG,             /* target headers byte order (big) */
 454     (HAS_RELOC | EXEC_P |               /* object flags */
 455      HAS_LINENO | HAS_DEBUG |
 456      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 457     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
 458     MY_symbol_leading_char,
 459     ' ',                                /* ar_pad_char */
 460     15,                         /* ar_max_namelen */
 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, /* data */
 464     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 465     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 466     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
 467     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 468      bfd_generic_archive_p, MY_core_file_p},
 469     {bfd_false, MY_mkobject,    /* bfd_set_format */
 470      _bfd_generic_mkarchive, bfd_false},
 471     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 472      _bfd_write_archive_contents, bfd_false},
 473
 474     BFD_JUMP_TABLE_GENERIC (MY),
 475     BFD_JUMP_TABLE_COPY (MY),
 476     BFD_JUMP_TABLE_CORE (MY),
 477     BFD_JUMP_TABLE_ARCHIVE (MY),
 478     BFD_JUMP_TABLE_SYMBOLS (MY),
 479     BFD_JUMP_TABLE_RELOCS (MY),
 480     BFD_JUMP_TABLE_WRITE (MY),
 481     BFD_JUMP_TABLE_LINK (MY),
 482     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 483
 484     & aout_mips_little_vec,
 485
 486     (PTR) MY_backend_data
 487   };