| 1 | /* BFD back-end for Motorola 68000 COFF binaries. |
| 2 | Copyright 1990, 91, 92, 93, 94, 95, 96, 1997 Free Software Foundation, Inc. |
| 3 | Written by Cygnus Support. |
| 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | #include "bfd.h" |
| 22 | #include "sysdep.h" |
| 23 | #include "libbfd.h" |
| 24 | #include "coff/m68k.h" |
| 25 | #include "coff/internal.h" |
| 26 | #include "libcoff.h" |
| 27 | |
| 28 | /* This source file is compiled multiple times for various m68k COFF |
| 29 | variants. The following macros control its behaviour: |
| 30 | |
| 31 | TARGET_SYM |
| 32 | The C name of the BFD target vector. The default is m68kcoff_vec. |
| 33 | TARGET_NAME |
| 34 | The user visible target name. The default is "coff-m68k". |
| 35 | NAMES_HAVE_UNDERSCORE |
| 36 | Whether symbol names have an underscore. |
| 37 | ONLY_DECLARE_RELOCS |
| 38 | Only declare the relocation howto array. Don't actually compile |
| 39 | it. The actual array will be picked up in another version of the |
| 40 | file. |
| 41 | STATIC_RELOCS |
| 42 | Make the relocation howto array, and associated functions, static. |
| 43 | COFF_COMMON_ADDEND |
| 44 | If this is defined, then, for a relocation against a common |
| 45 | symbol, the object file holds the value (the size) of the common |
| 46 | symbol. If this is not defined, then, for a relocation against a |
| 47 | common symbol, the object file holds zero. */ |
| 48 | |
| 49 | #define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2) |
| 50 | |
| 51 | #ifndef COFF_PAGE_SIZE |
| 52 | /* The page size is a guess based on ELF. */ |
| 53 | #define COFF_PAGE_SIZE 0x2000 |
| 54 | #endif |
| 55 | |
| 56 | #ifndef COFF_COMMON_ADDEND |
| 57 | #define RELOC_SPECIAL_FN 0 |
| 58 | #else |
| 59 | static bfd_reloc_status_type m68kcoff_common_addend_special_fn |
| 60 | PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **)); |
| 61 | static reloc_howto_type *m68kcoff_common_addend_rtype_to_howto |
| 62 | PARAMS ((bfd *, asection *, struct internal_reloc *, |
| 63 | struct coff_link_hash_entry *, struct internal_syment *, |
| 64 | bfd_vma *)); |
| 65 | #define RELOC_SPECIAL_FN m68kcoff_common_addend_special_fn |
| 66 | #endif |
| 67 | |
| 68 | static boolean m68k_coff_is_local_label_name PARAMS ((bfd *, const char *)); |
| 69 | |
| 70 | /* On the delta, a symbol starting with L% is local. We won't see |
| 71 | such a symbol on other platforms, so it should be safe to always |
| 72 | consider it local here. */ |
| 73 | |
| 74 | static boolean |
| 75 | m68k_coff_is_local_label_name (abfd, name) |
| 76 | bfd *abfd; |
| 77 | const char *name; |
| 78 | { |
| 79 | if (name[0] == 'L' && name[1] == '%') |
| 80 | return true; |
| 81 | |
| 82 | return _bfd_coff_is_local_label_name (abfd, name); |
| 83 | } |
| 84 | |
| 85 | #ifndef STATIC_RELOCS |
| 86 | /* Clean up namespace. */ |
| 87 | #define m68kcoff_howto_table _bfd_m68kcoff_howto_table |
| 88 | #define m68k_rtype2howto _bfd_m68kcoff_rtype2howto |
| 89 | #define m68k_howto2rtype _bfd_m68kcoff_howto2rtype |
| 90 | #define m68k_reloc_type_lookup _bfd_m68kcoff_reloc_type_lookup |
| 91 | #endif |
| 92 | |
| 93 | #ifdef ONLY_DECLARE_RELOCS |
| 94 | extern reloc_howto_type m68kcoff_howto_table[]; |
| 95 | #else |
| 96 | #ifdef STATIC_RELOCS |
| 97 | static |
| 98 | #endif |
| 99 | reloc_howto_type m68kcoff_howto_table[] = |
| 100 | { |
| 101 | HOWTO(R_RELBYTE, 0, 0, 8, false, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "8", true, 0x000000ff,0x000000ff, false), |
| 102 | HOWTO(R_RELWORD, 0, 1, 16, false, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "16", true, 0x0000ffff,0x0000ffff, false), |
| 103 | HOWTO(R_RELLONG, 0, 2, 32, false, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "32", true, 0xffffffff,0xffffffff, false), |
| 104 | HOWTO(R_PCRBYTE, 0, 0, 8, true, 0, complain_overflow_signed, RELOC_SPECIAL_FN, "DISP8", true, 0x000000ff,0x000000ff, false), |
| 105 | HOWTO(R_PCRWORD, 0, 1, 16, true, 0, complain_overflow_signed, RELOC_SPECIAL_FN, "DISP16", true, 0x0000ffff,0x0000ffff, false), |
| 106 | HOWTO(R_PCRLONG, 0, 2, 32, true, 0, complain_overflow_signed, RELOC_SPECIAL_FN, "DISP32", true, 0xffffffff,0xffffffff, false), |
| 107 | HOWTO(R_RELLONG_NEG, 0, -2, 32, false, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "-32", true, 0xffffffff,0xffffffff, false), |
| 108 | }; |
| 109 | #endif /* not ONLY_DECLARE_RELOCS */ |
| 110 | |
| 111 | #ifndef BADMAG |
| 112 | #define BADMAG(x) M68KBADMAG(x) |
| 113 | #endif |
| 114 | #define M68 1 /* Customize coffcode.h */ |
| 115 | |
| 116 | /* Turn a howto into a reloc number */ |
| 117 | |
| 118 | #ifdef ONLY_DECLARE_RELOCS |
| 119 | extern void m68k_rtype2howto PARAMS ((arelent *internal, int relocentry)); |
| 120 | extern int m68k_howto2rtype PARAMS ((reloc_howto_type *)); |
| 121 | extern reloc_howto_type *m68k_reloc_type_lookup |
| 122 | PARAMS ((bfd *, bfd_reloc_code_real_type)); |
| 123 | #else |
| 124 | #ifdef STATIC_RELOCS |
| 125 | static |
| 126 | #endif |
| 127 | void |
| 128 | m68k_rtype2howto(internal, relocentry) |
| 129 | arelent *internal; |
| 130 | int relocentry; |
| 131 | { |
| 132 | switch (relocentry) |
| 133 | { |
| 134 | case R_RELBYTE: internal->howto = m68kcoff_howto_table + 0; break; |
| 135 | case R_RELWORD: internal->howto = m68kcoff_howto_table + 1; break; |
| 136 | case R_RELLONG: internal->howto = m68kcoff_howto_table + 2; break; |
| 137 | case R_PCRBYTE: internal->howto = m68kcoff_howto_table + 3; break; |
| 138 | case R_PCRWORD: internal->howto = m68kcoff_howto_table + 4; break; |
| 139 | case R_PCRLONG: internal->howto = m68kcoff_howto_table + 5; break; |
| 140 | case R_RELLONG_NEG: internal->howto = m68kcoff_howto_table + 6; break; |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | #ifdef STATIC_RELOCS |
| 145 | static |
| 146 | #endif |
| 147 | int |
| 148 | m68k_howto2rtype (internal) |
| 149 | reloc_howto_type *internal; |
| 150 | { |
| 151 | if (internal->pc_relative) |
| 152 | { |
| 153 | switch (internal->bitsize) |
| 154 | { |
| 155 | case 32: return R_PCRLONG; |
| 156 | case 16: return R_PCRWORD; |
| 157 | case 8: return R_PCRBYTE; |
| 158 | } |
| 159 | } |
| 160 | else |
| 161 | { |
| 162 | switch (internal->bitsize) |
| 163 | { |
| 164 | case 32: return R_RELLONG; |
| 165 | case 16: return R_RELWORD; |
| 166 | case 8: return R_RELBYTE; |
| 167 | } |
| 168 | } |
| 169 | return R_RELLONG; |
| 170 | } |
| 171 | |
| 172 | #ifdef STATIC_RELOCS |
| 173 | static |
| 174 | #endif |
| 175 | reloc_howto_type * |
| 176 | m68k_reloc_type_lookup (abfd, code) |
| 177 | bfd *abfd; |
| 178 | bfd_reloc_code_real_type code; |
| 179 | { |
| 180 | switch (code) |
| 181 | { |
| 182 | default: return NULL; |
| 183 | case BFD_RELOC_8: return m68kcoff_howto_table + 0; |
| 184 | case BFD_RELOC_16: return m68kcoff_howto_table + 1; |
| 185 | case BFD_RELOC_CTOR: |
| 186 | case BFD_RELOC_32: return m68kcoff_howto_table + 2; |
| 187 | case BFD_RELOC_8_PCREL: return m68kcoff_howto_table + 3; |
| 188 | case BFD_RELOC_16_PCREL: return m68kcoff_howto_table + 4; |
| 189 | case BFD_RELOC_32_PCREL: return m68kcoff_howto_table + 5; |
| 190 | /* FIXME: There doesn't seem to be a code for R_RELLONG_NEG. */ |
| 191 | } |
| 192 | /*NOTREACHED*/ |
| 193 | } |
| 194 | |
| 195 | #endif /* not ONLY_DECLARE_RELOCS */ |
| 196 | |
| 197 | #define RTYPE2HOWTO(internal, relocentry) \ |
| 198 | m68k_rtype2howto(internal, (relocentry)->r_type) |
| 199 | |
| 200 | #define SELECT_RELOC(external, internal) \ |
| 201 | external.r_type = m68k_howto2rtype (internal) |
| 202 | |
| 203 | #define coff_bfd_reloc_type_lookup m68k_reloc_type_lookup |
| 204 | |
| 205 | #ifndef COFF_COMMON_ADDEND |
| 206 | #ifndef coff_rtype_to_howto |
| 207 | |
| 208 | #define coff_rtype_to_howto m68kcoff_rtype_to_howto |
| 209 | |
| 210 | static reloc_howto_type *m68kcoff_rtype_to_howto |
| 211 | PARAMS ((bfd *, asection *, struct internal_reloc *, |
| 212 | struct coff_link_hash_entry *, struct internal_syment *, |
| 213 | bfd_vma *)); |
| 214 | |
| 215 | /*ARGSUSED*/ |
| 216 | static reloc_howto_type * |
| 217 | m68kcoff_rtype_to_howto (abfd, sec, rel, h, sym, addendp) |
| 218 | bfd *abfd; |
| 219 | asection *sec; |
| 220 | struct internal_reloc *rel; |
| 221 | struct coff_link_hash_entry *h; |
| 222 | struct internal_syment *sym; |
| 223 | bfd_vma *addendp; |
| 224 | { |
| 225 | arelent relent; |
| 226 | reloc_howto_type *howto; |
| 227 | |
| 228 | RTYPE2HOWTO (&relent, rel); |
| 229 | |
| 230 | howto = relent.howto; |
| 231 | |
| 232 | if (howto->pc_relative) |
| 233 | *addendp += sec->vma; |
| 234 | |
| 235 | return howto; |
| 236 | } |
| 237 | |
| 238 | #endif /* ! defined (coff_rtype_to_howto) */ |
| 239 | #endif /* ! defined (COFF_COMMON_ADDEND) */ |
| 240 | \f |
| 241 | #ifdef COFF_COMMON_ADDEND |
| 242 | |
| 243 | /* If COFF_COMMON_ADDEND is defined, then when using m68k COFF the |
| 244 | value stored in the .text section for a reference to a common |
| 245 | symbol is the value itself plus any desired offset. (taken from |
| 246 | work done by Ian Taylor, Cygnus Support, for I386 COFF). */ |
| 247 | |
| 248 | /* If we are producing relocateable output, we need to do some |
| 249 | adjustments to the object file that are not done by the |
| 250 | bfd_perform_relocation function. This function is called by every |
| 251 | reloc type to make any required adjustments. */ |
| 252 | |
| 253 | static bfd_reloc_status_type |
| 254 | m68kcoff_common_addend_special_fn (abfd, reloc_entry, symbol, data, |
| 255 | input_section, output_bfd, error_message) |
| 256 | bfd *abfd; |
| 257 | arelent *reloc_entry; |
| 258 | asymbol *symbol; |
| 259 | PTR data; |
| 260 | asection *input_section; |
| 261 | bfd *output_bfd; |
| 262 | char **error_message; |
| 263 | { |
| 264 | symvalue diff; |
| 265 | |
| 266 | if (output_bfd == (bfd *) NULL) |
| 267 | return bfd_reloc_continue; |
| 268 | |
| 269 | if (bfd_is_com_section (symbol->section)) |
| 270 | { |
| 271 | /* We are relocating a common symbol. The current value in the |
| 272 | object file is ORIG + OFFSET, where ORIG is the value of the |
| 273 | common symbol as seen by the object file when it was compiled |
| 274 | (this may be zero if the symbol was undefined) and OFFSET is |
| 275 | the offset into the common symbol (normally zero, but may be |
| 276 | non-zero when referring to a field in a common structure). |
| 277 | ORIG is the negative of reloc_entry->addend, which is set by |
| 278 | the CALC_ADDEND macro below. We want to replace the value in |
| 279 | the object file with NEW + OFFSET, where NEW is the value of |
| 280 | the common symbol which we are going to put in the final |
| 281 | object file. NEW is symbol->value. */ |
| 282 | diff = symbol->value + reloc_entry->addend; |
| 283 | } |
| 284 | else |
| 285 | { |
| 286 | /* For some reason bfd_perform_relocation always effectively |
| 287 | ignores the addend for a COFF target when producing |
| 288 | relocateable output. This seems to be always wrong for 386 |
| 289 | COFF, so we handle the addend here instead. */ |
| 290 | diff = reloc_entry->addend; |
| 291 | } |
| 292 | |
| 293 | #define DOIT(x) \ |
| 294 | x = ((x & ~howto->dst_mask) | (((x & howto->src_mask) + diff) & howto->dst_mask)) |
| 295 | |
| 296 | if (diff != 0) |
| 297 | { |
| 298 | reloc_howto_type *howto = reloc_entry->howto; |
| 299 | unsigned char *addr = (unsigned char *) data + reloc_entry->address; |
| 300 | |
| 301 | switch (howto->size) |
| 302 | { |
| 303 | case 0: |
| 304 | { |
| 305 | char x = bfd_get_8 (abfd, addr); |
| 306 | DOIT (x); |
| 307 | bfd_put_8 (abfd, x, addr); |
| 308 | } |
| 309 | break; |
| 310 | |
| 311 | case 1: |
| 312 | { |
| 313 | short x = bfd_get_16 (abfd, addr); |
| 314 | DOIT (x); |
| 315 | bfd_put_16 (abfd, x, addr); |
| 316 | } |
| 317 | break; |
| 318 | |
| 319 | case 2: |
| 320 | { |
| 321 | long x = bfd_get_32 (abfd, addr); |
| 322 | DOIT (x); |
| 323 | bfd_put_32 (abfd, x, addr); |
| 324 | } |
| 325 | break; |
| 326 | |
| 327 | default: |
| 328 | abort (); |
| 329 | } |
| 330 | } |
| 331 | |
| 332 | /* Now let bfd_perform_relocation finish everything up. */ |
| 333 | return bfd_reloc_continue; |
| 334 | } |
| 335 | |
| 336 | /* Compute the addend of a reloc. If the reloc is to a common symbol, |
| 337 | the object file contains the value of the common symbol. By the |
| 338 | time this is called, the linker may be using a different symbol |
| 339 | from a different object file with a different value. Therefore, we |
| 340 | hack wildly to locate the original symbol from this file so that we |
| 341 | can make the correct adjustment. This macro sets coffsym to the |
| 342 | symbol from the original file, and uses it to set the addend value |
| 343 | correctly. If this is not a common symbol, the usual addend |
| 344 | calculation is done, except that an additional tweak is needed for |
| 345 | PC relative relocs. |
| 346 | FIXME: This macro refers to symbols and asect; these are from the |
| 347 | calling function, not the macro arguments. */ |
| 348 | |
| 349 | #define CALC_ADDEND(abfd, ptr, reloc, cache_ptr) \ |
| 350 | { \ |
| 351 | coff_symbol_type *coffsym = (coff_symbol_type *) NULL; \ |
| 352 | if (ptr && bfd_asymbol_bfd (ptr) != abfd) \ |
| 353 | coffsym = (obj_symbols (abfd) \ |
| 354 | + (cache_ptr->sym_ptr_ptr - symbols)); \ |
| 355 | else if (ptr) \ |
| 356 | coffsym = coff_symbol_from (abfd, ptr); \ |
| 357 | if (coffsym != (coff_symbol_type *) NULL \ |
| 358 | && coffsym->native->u.syment.n_scnum == 0) \ |
| 359 | cache_ptr->addend = - coffsym->native->u.syment.n_value; \ |
| 360 | else if (ptr && bfd_asymbol_bfd (ptr) == abfd \ |
| 361 | && ptr->section != (asection *) NULL) \ |
| 362 | cache_ptr->addend = - (ptr->section->vma + ptr->value); \ |
| 363 | else \ |
| 364 | cache_ptr->addend = 0; \ |
| 365 | if (ptr && (reloc.r_type == R_PCRBYTE \ |
| 366 | || reloc.r_type == R_PCRWORD \ |
| 367 | || reloc.r_type == R_PCRLONG)) \ |
| 368 | cache_ptr->addend += asect->vma; \ |
| 369 | } |
| 370 | |
| 371 | #ifndef coff_rtype_to_howto |
| 372 | |
| 373 | /* coff-m68k.c uses the special COFF backend linker. We need to |
| 374 | adjust common symbols. */ |
| 375 | |
| 376 | /*ARGSUSED*/ |
| 377 | static reloc_howto_type * |
| 378 | m68kcoff_common_addend_rtype_to_howto (abfd, sec, rel, h, sym, addendp) |
| 379 | bfd *abfd; |
| 380 | asection *sec; |
| 381 | struct internal_reloc *rel; |
| 382 | struct coff_link_hash_entry *h; |
| 383 | struct internal_syment *sym; |
| 384 | bfd_vma *addendp; |
| 385 | { |
| 386 | arelent relent; |
| 387 | reloc_howto_type *howto; |
| 388 | |
| 389 | RTYPE2HOWTO (&relent, rel); |
| 390 | |
| 391 | howto = relent.howto; |
| 392 | |
| 393 | if (howto->pc_relative) |
| 394 | *addendp += sec->vma; |
| 395 | |
| 396 | if (sym != NULL && sym->n_scnum == 0 && sym->n_value != 0) |
| 397 | { |
| 398 | /* This is a common symbol. The section contents include the |
| 399 | size (sym->n_value) as an addend. The relocate_section |
| 400 | function will be adding in the final value of the symbol. We |
| 401 | need to subtract out the current size in order to get the |
| 402 | correct result. */ |
| 403 | BFD_ASSERT (h != NULL); |
| 404 | *addendp -= sym->n_value; |
| 405 | } |
| 406 | |
| 407 | /* If the output symbol is common (in which case this must be a |
| 408 | relocateable link), we need to add in the final size of the |
| 409 | common symbol. */ |
| 410 | if (h != NULL && h->root.type == bfd_link_hash_common) |
| 411 | *addendp += h->root.u.c.size; |
| 412 | |
| 413 | return howto; |
| 414 | } |
| 415 | |
| 416 | #define coff_rtype_to_howto m68kcoff_common_addend_rtype_to_howto |
| 417 | |
| 418 | #endif /* ! defined (coff_rtype_to_howto) */ |
| 419 | |
| 420 | #endif /* COFF_COMMON_ADDEND */ |
| 421 | \f |
| 422 | #define coff_bfd_is_local_label_name m68k_coff_is_local_label_name |
| 423 | |
| 424 | #define coff_relocate_section _bfd_coff_generic_relocate_section |
| 425 | |
| 426 | #include "coffcode.h" |
| 427 | |
| 428 | #ifndef TARGET_SYM |
| 429 | #define TARGET_SYM m68kcoff_vec |
| 430 | #endif |
| 431 | |
| 432 | #ifndef TARGET_NAME |
| 433 | #define TARGET_NAME "coff-m68k" |
| 434 | #endif |
| 435 | |
| 436 | const bfd_target TARGET_SYM = |
| 437 | { |
| 438 | TARGET_NAME, |
| 439 | bfd_target_coff_flavour, |
| 440 | BFD_ENDIAN_BIG, /* data byte order is big */ |
| 441 | BFD_ENDIAN_BIG, /* header byte order is big */ |
| 442 | |
| 443 | (HAS_RELOC | EXEC_P | /* object flags */ |
| 444 | HAS_LINENO | HAS_DEBUG | |
| 445 | HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED), |
| 446 | |
| 447 | (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */ |
| 448 | #ifdef NAMES_HAVE_UNDERSCORE |
| 449 | '_', |
| 450 | #else |
| 451 | 0, /* leading underscore */ |
| 452 | #endif |
| 453 | '/', /* ar_pad_char */ |
| 454 | 15, /* ar_max_namelen */ |
| 455 | bfd_getb64, bfd_getb_signed_64, bfd_putb64, |
| 456 | bfd_getb32, bfd_getb_signed_32, bfd_putb32, |
| 457 | bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */ |
| 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, /* hdrs */ |
| 461 | |
| 462 | {_bfd_dummy_target, coff_object_p, /* bfd_check_format */ |
| 463 | bfd_generic_archive_p, _bfd_dummy_target}, |
| 464 | {bfd_false, coff_mkobject, _bfd_generic_mkarchive, /* bfd_set_format */ |
| 465 | bfd_false}, |
| 466 | {bfd_false, coff_write_object_contents, /* bfd_write_contents */ |
| 467 | _bfd_write_archive_contents, bfd_false}, |
| 468 | |
| 469 | BFD_JUMP_TABLE_GENERIC (coff), |
| 470 | BFD_JUMP_TABLE_COPY (coff), |
| 471 | BFD_JUMP_TABLE_CORE (_bfd_nocore), |
| 472 | BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff), |
| 473 | BFD_JUMP_TABLE_SYMBOLS (coff), |
| 474 | BFD_JUMP_TABLE_RELOCS (coff), |
| 475 | BFD_JUMP_TABLE_WRITE (coff), |
| 476 | BFD_JUMP_TABLE_LINK (coff), |
| 477 | BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), |
| 478 | |
| 479 | COFF_SWAP_TABLE |
| 480 | }; |