bfd/mipsbsd.c

   1 /* BFD backend for MIPS BSD (a.out) binaries.
   2    Copyright (C) 1993, 1994 Free Software Foundation, Inc.
   3    Written by Ralph Campbell.
   4
   5 This file is part of BFD, the Binary File Descriptor library.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #define BYTES_IN_WORD 4
  22 #define ARCH 32
  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 PAGE_SIZE 4096
  33 #define SEGMENT_SIZE 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 void MY(set_arch_mach) PARAMS ((bfd *abfd, int 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 void
  71 MY(set_arch_mach) (abfd, machtype)
  72      bfd *abfd;
  73      int machtype;
  74 {
  75   enum bfd_architecture arch;
  76   long machine;
  77
  78   /* Determine the architecture and machine type of the object file. */
  79   switch (machtype) {
  80
  81   case M_MIPS1:
  82     arch = bfd_arch_mips;
  83     machine = 3000;
  84     break;
  85
  86   case M_MIPS2:
  87     arch = bfd_arch_mips;
  88     machine = 4000;
  89     break;
  90
  91   default:
  92     arch = bfd_arch_obscure;
  93     machine = 0;
  94     break;
  95   }
  96   bfd_set_arch_mach(abfd, arch, machine);
  97 }
  98
  99 /* Determine the size of a relocation entry, based on the architecture */
 100 static void
 101 MY(choose_reloc_size) (abfd)
 102      bfd *abfd;
 103 {
 104   switch (bfd_get_arch(abfd)) {
 105   case bfd_arch_sparc:
 106   case bfd_arch_a29k:
 107   case bfd_arch_mips:
 108     obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;
 109     break;
 110   default:
 111     obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;
 112     break;
 113   }
 114 }
 115
 116 /* Write an object file in BSD a.out format.
 117   Section contents have already been written.  We write the
 118   file header, symbols, and relocation.  */
 119
 120 static boolean
 121 MY(write_object_contents) (abfd)
 122      bfd *abfd;
 123 {
 124   struct external_exec exec_bytes;
 125   struct internal_exec *execp = exec_hdr (abfd);
 126
 127   /* Magic number, maestro, please!  */
 128   switch (bfd_get_arch(abfd)) {
 129   case bfd_arch_m68k:
 130     switch (bfd_get_mach(abfd)) {
 131     case 68010:
 132       N_SET_MACHTYPE(*execp, M_68010);
 133       break;
 134     default:
 135     case 68020:
 136       N_SET_MACHTYPE(*execp, M_68020);
 137       break;
 138     }
 139     break;
 140   case bfd_arch_sparc:
 141     N_SET_MACHTYPE(*execp, M_SPARC);
 142     break;
 143   case bfd_arch_i386:
 144     N_SET_MACHTYPE(*execp, M_386);
 145     break;
 146   case bfd_arch_a29k:
 147     N_SET_MACHTYPE(*execp, M_29K);
 148     break;
 149   case bfd_arch_mips:
 150     switch (bfd_get_mach(abfd)) {
 151     case 4000:
 152     case 6000:
 153       N_SET_MACHTYPE(*execp, M_MIPS2);
 154       break;
 155     default:
 156       N_SET_MACHTYPE(*execp, M_MIPS1);
 157       break;
 158     }
 159     break;
 160   default:
 161     N_SET_MACHTYPE(*execp, M_UNKNOWN);
 162   }
 163
 164   MY(choose_reloc_size)(abfd);
 165
 166   WRITE_HEADERS(abfd, execp);
 167
 168   return true;
 169 }
 170
 171 /*
 172  * MIPS relocation types.
 173  */
 174 #define MIPS_RELOC_32           0
 175 #define MIPS_RELOC_JMP          1
 176 #define MIPS_RELOC_WDISP16      2
 177 #define MIPS_RELOC_HI16         3
 178 #define MIPS_RELOC_HI16_S       4
 179 #define MIPS_RELOC_LO16         5
 180
 181 /*
 182  * This is only called when performing a BFD_RELOC_MIPS_JMP relocation.
 183  * The jump destination address is formed from the upper 4 bits of the
 184  * "current" program counter concatenated with the jump instruction's
 185  * 26 bit field and two trailing zeros.
 186  * If the destination address is not in the same segment as the "current"
 187  * program counter, then we need to signal an error.
 188  */
 189 static bfd_reloc_status_type
 190 mips_fix_jmp_addr (abfd,reloc_entry,symbol,data,input_section,output_bfd)
 191      bfd *abfd;
 192      arelent *reloc_entry;
 193      struct symbol_cache_entry *symbol;
 194      PTR data;
 195      asection *input_section;
 196      bfd *output_bfd;
 197 {
 198   bfd_vma relocation, pc;
 199
 200   /* If this is a partial relocation, just continue. */
 201   if (output_bfd != (bfd *)NULL)
 202     return bfd_reloc_continue;
 203
 204   /* If this is an undefined symbol, return error */
 205   if (symbol->section == &bfd_und_section
 206       && (symbol->flags & BSF_WEAK) == 0)
 207     return bfd_reloc_undefined;
 208
 209   /*
 210    * Work out which section the relocation is targetted at and the
 211    * initial relocation command value.
 212    */
 213   if (bfd_is_com_section (symbol->section))
 214     relocation = 0;
 215   else
 216     relocation = symbol->value;
 217
 218   relocation += symbol->section->output_section->vma;
 219   relocation += symbol->section->output_offset;
 220   relocation += reloc_entry->addend;
 221
 222   pc = input_section->output_section->vma + input_section->output_offset +
 223     reloc_entry->address + 4;
 224
 225   if ((relocation & 0xF0000000) != (pc & 0xF0000000))
 226     return bfd_reloc_overflow;
 227
 228   return bfd_reloc_continue;
 229 }
 230
 231 /*
 232  * This is only called when performing a BFD_RELOC_HI16_S relocation.
 233  * We need to see if bit 15 is set in the result. If it is, we add
 234  * 0x10000 and continue normally. This will compensate for the sign extension
 235  * when the low bits are added at run time.
 236  */
 237 static bfd_reloc_status_type
 238 mips_fix_hi16_s PARAMS ((bfd *, arelent *, asymbol *, PTR,
 239                          asection *, bfd *, char **));
 240
 241 static bfd_reloc_status_type
 242 mips_fix_hi16_s (abfd, reloc_entry, symbol, data, input_section,
 243                  output_bfd, error_message)
 244      bfd *abfd;
 245      arelent *reloc_entry;
 246      asymbol *symbol;
 247      PTR data;
 248      asection *input_section;
 249      bfd *output_bfd;
 250      char **error_message;
 251 {
 252   bfd_vma relocation;
 253
 254   /* If this is a partial relocation, just continue. */
 255   if (output_bfd != (bfd *)NULL)
 256     return bfd_reloc_continue;
 257
 258   /* If this is an undefined symbol, return error */
 259   if (symbol->section == &bfd_und_section
 260       && (symbol->flags & BSF_WEAK) == 0)
 261     return bfd_reloc_undefined;
 262
 263   /*
 264    * Work out which section the relocation is targetted at and the
 265    * initial relocation command value.
 266    */
 267   if (bfd_is_com_section (symbol->section))
 268     relocation = 0;
 269   else
 270     relocation = symbol->value;
 271
 272   relocation += symbol->section->output_section->vma;
 273   relocation += symbol->section->output_offset;
 274   relocation += reloc_entry->addend;
 275
 276   if (relocation & 0x8000)
 277     reloc_entry->addend += 0x10000;
 278
 279   return bfd_reloc_continue;
 280 }
 281
 282 static reloc_howto_type mips_howto_table_ext[] = {
 283   {MIPS_RELOC_32,      0, 2, 32, false, 0,  complain_overflow_bitfield, 0,
 284         "32",       false, 0, 0xffffffff, false},
 285   {MIPS_RELOC_JMP,     2, 2, 26, false, 0, complain_overflow_dont,
 286         mips_fix_jmp_addr,
 287         "MIPS_JMP", false, 0, 0x03ffffff, false},
 288   {MIPS_RELOC_WDISP16, 2, 1, 16, true,  0, complain_overflow_signed, 0,
 289         "WDISP16",  false, 0, 0x0000ffff, false},
 290   {MIPS_RELOC_HI16,   16, 1, 16, false, 0, complain_overflow_bitfield, 0,
 291         "HI16",     false, 0, 0x0000ffff, false},
 292   {MIPS_RELOC_HI16_S, 16, 1, 16, false, 0, complain_overflow_bitfield,
 293         mips_fix_hi16_s,
 294         "HI16_S",   false, 0, 0x0000ffff, false},
 295   {MIPS_RELOC_LO16,    0, 1, 16, false, 0, complain_overflow_dont, 0,
 296         "LO16",     false, 0, 0x0000ffff, false},
 297 };
 298
 299 static const reloc_howto_type *
 300 MY(reloc_howto_type_lookup) (abfd, code)
 301      bfd *abfd;
 302      bfd_reloc_code_real_type code;
 303 {
 304
 305   if (bfd_get_arch (abfd) != bfd_arch_mips)
 306     return 0;
 307
 308   switch (code)
 309     {
 310     case BFD_RELOC_32:
 311       return (&mips_howto_table_ext[MIPS_RELOC_32]);
 312     case BFD_RELOC_MIPS_JMP:
 313       return (&mips_howto_table_ext[MIPS_RELOC_JMP]);
 314     case BFD_RELOC_16_PCREL_S2:
 315       return (&mips_howto_table_ext[MIPS_RELOC_WDISP16]);
 316     case BFD_RELOC_HI16:
 317       return (&mips_howto_table_ext[MIPS_RELOC_HI16]);
 318     case BFD_RELOC_HI16_S:
 319       return (&mips_howto_table_ext[MIPS_RELOC_HI16_S]);
 320     case BFD_RELOC_LO16:
 321       return (&mips_howto_table_ext[MIPS_RELOC_LO16]);
 322     default:
 323       return 0;
 324     }
 325 }
 326
 327 /*
 328  * This is just like the standard aoutx.h version but we need to do our
 329  * own mapping of external reloc type values to howto entries.
 330  */
 331 long
 332 MY(canonicalize_reloc)(abfd, section, relptr, symbols)
 333       bfd *abfd;
 334       sec_ptr section;
 335       arelent **relptr;
 336       asymbol **symbols;
 337 {
 338   arelent *tblptr = section->relocation;
 339   unsigned int count, c;
 340   extern reloc_howto_type NAME(aout,ext_howto_table)[];
 341
 342   /* If we have already read in the relocation table, return the values. */
 343   if (section->flags & SEC_CONSTRUCTOR) {
 344     arelent_chain *chain = section->constructor_chain;
 345
 346     for (count = 0; count < section->reloc_count; count++) {
 347       *relptr++ = &chain->relent;
 348       chain = chain->next;
 349     }
 350     *relptr = 0;
 351     return section->reloc_count;
 352   }
 353   if (tblptr && section->reloc_count) {
 354     for (count = 0; count++ < section->reloc_count;)
 355       *relptr++ = tblptr++;
 356     *relptr = 0;
 357     return section->reloc_count;
 358   }
 359
 360   if (!NAME(aout,slurp_reloc_table)(abfd, section, symbols))
 361     return -1;
 362   tblptr = section->relocation;
 363
 364   /* fix up howto entries */
 365   for (count = 0; count++ < section->reloc_count;)
 366     {
 367       c = tblptr->howto - NAME(aout,ext_howto_table);
 368       tblptr->howto = &mips_howto_table_ext[c];
 369
 370       *relptr++ = tblptr++;
 371     }
 372   *relptr = 0;
 373   return section->reloc_count;
 374 }
 375
 376 static CONST struct aout_backend_data MY(backend_data) = {
 377   0,                            /* zmagic contiguous */
 378   1,                            /* text incl header */
 379   0,                            /* exec_hdr_flags */
 380   PAGE_SIZE,                    /* text vma */
 381   MY_set_sizes,
 382   0,                            /* text size includes exec header */
 383   0,                            /* add_dynamic_symbols */
 384   0,                            /* add_one_symbol */
 385   0,                            /* link_dynamic_object */
 386   0,                            /* write_dynamic_symbol */
 387   0,                            /* check_dynamic_reloc */
 388   0                             /* finish_dynamic_link */
 389 };
 390
 391 bfd_target aout_mips_little_vec =
 392 {
 393   "a.out-mips-little",          /* name */
 394   bfd_target_aout_flavour,
 395   false,                        /* target byte order (little) */
 396   false,                        /* target headers byte order (little) */
 397   (HAS_RELOC | EXEC_P |         /* object flags */
 398    HAS_LINENO | HAS_DEBUG |
 399    HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 400   (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 401   MY_symbol_leading_char,
 402   ' ',                          /* ar_pad_char */
 403   15,                           /* ar_max_namelen */
 404   1,                            /* minimum alignment */
 405   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 406      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 407      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
 408   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 409      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 410      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
 411     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 412        bfd_generic_archive_p, MY_core_file_p},
 413     {bfd_false, MY_mkobject,    /* bfd_set_format */
 414        _bfd_generic_mkarchive, bfd_false},
 415     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 416        _bfd_write_archive_contents, bfd_false},
 417
 418      BFD_JUMP_TABLE_GENERIC (MY),
 419      BFD_JUMP_TABLE_COPY (MY),
 420      BFD_JUMP_TABLE_CORE (MY),
 421      BFD_JUMP_TABLE_ARCHIVE (MY),
 422      BFD_JUMP_TABLE_SYMBOLS (MY),
 423      BFD_JUMP_TABLE_RELOCS (MY),
 424      BFD_JUMP_TABLE_WRITE (MY),
 425      BFD_JUMP_TABLE_LINK (MY),
 426      BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 427
 428   (PTR) MY_backend_data,
 429 };
 430
 431 bfd_target aout_mips_big_vec =
 432 {
 433   "a.out-mips-big",             /* name */
 434   bfd_target_aout_flavour,
 435   true,                         /* target byte order (big) */
 436   true,                         /* target headers byte order (big) */
 437   (HAS_RELOC | EXEC_P |         /* object flags */
 438    HAS_LINENO | HAS_DEBUG |
 439    HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 440   (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 441   MY_symbol_leading_char,
 442   ' ',                          /* ar_pad_char */
 443   15,                           /* ar_max_namelen */
 444   1,                            /* minimum alignment */
 445   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 446      bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 447      bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
 448   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 449      bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 450      bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
 451     {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
 452        bfd_generic_archive_p, MY_core_file_p},
 453     {bfd_false, MY_mkobject,    /* bfd_set_format */
 454        _bfd_generic_mkarchive, bfd_false},
 455     {bfd_false, MY_write_object_contents, /* bfd_write_contents */
 456        _bfd_write_archive_contents, bfd_false},
 457
 458      BFD_JUMP_TABLE_GENERIC (MY),
 459      BFD_JUMP_TABLE_COPY (MY),
 460      BFD_JUMP_TABLE_CORE (MY),
 461      BFD_JUMP_TABLE_ARCHIVE (MY),
 462      BFD_JUMP_TABLE_SYMBOLS (MY),
 463      BFD_JUMP_TABLE_RELOCS (MY),
 464      BFD_JUMP_TABLE_WRITE (MY),
 465      BFD_JUMP_TABLE_LINK (MY),
 466      BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 467
 468   (PTR) MY_backend_data,
 469 };