1 /* BFD COFF object file private structure. 2 Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 3 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 4 Free Software Foundation, Inc. 5 Written by Cygnus Support. 6 7 This file is part of BFD, the Binary File Descriptor library. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 22 MA 02110-1301, USA. */ 23 24 #include "bfdlink.h" 25 26 /* Object file tdata; access macros. */ 27 28 #define coff_data(bfd) ((bfd)->tdata.coff_obj_data) 29 #define obj_pe(bfd) (coff_data (bfd)->pe) 30 #define obj_symbols(bfd) (coff_data (bfd)->symbols) 31 #define obj_sym_filepos(bfd) (coff_data (bfd)->sym_filepos) 32 #define obj_relocbase(bfd) (coff_data (bfd)->relocbase) 33 #define obj_raw_syments(bfd) (coff_data (bfd)->raw_syments) 34 #define obj_raw_syment_count(bfd) (coff_data (bfd)->raw_syment_count) 35 #define obj_convert(bfd) (coff_data (bfd)->conversion_table) 36 #define obj_conv_table_size(bfd) (coff_data (bfd)->conv_table_size) 37 #define obj_coff_external_syms(bfd) (coff_data (bfd)->external_syms) 38 #define obj_coff_keep_syms(bfd) (coff_data (bfd)->keep_syms) 39 #define obj_coff_strings(bfd) (coff_data (bfd)->strings) 40 #define obj_coff_keep_strings(bfd) (coff_data (bfd)->keep_strings) 41 #define obj_coff_sym_hashes(bfd) (coff_data (bfd)->sym_hashes) 42 #define obj_coff_strings_written(bfd) (coff_data (bfd)->strings_written) 43 #define obj_coff_local_toc_table(bfd) (coff_data (bfd)->local_toc_sym_map) 44 45 /* `Tdata' information kept for COFF files. */ 46 47 typedef struct coff_tdata 48 { 49 struct coff_symbol_struct *symbols; /* Symtab for input bfd. */ 50 unsigned int *conversion_table; 51 int conv_table_size; 52 file_ptr sym_filepos; 53 54 struct coff_ptr_struct *raw_syments; 55 unsigned long raw_syment_count; 56 57 /* These are only valid once writing has begun. */ 58 long int relocbase; 59 60 /* These members communicate important constants about the symbol table 61 to GDB's symbol-reading code. These `constants' unfortunately vary 62 from coff implementation to implementation... */ 63 unsigned local_n_btmask; 64 unsigned local_n_btshft; 65 unsigned local_n_tmask; 66 unsigned local_n_tshift; 67 unsigned local_symesz; 68 unsigned local_auxesz; 69 unsigned local_linesz; 70 71 /* The unswapped external symbols. May be NULL. Read by 72 _bfd_coff_get_external_symbols. */ 73 void * external_syms; 74 /* If this is TRUE, the external_syms may not be freed. */ 75 bfd_boolean keep_syms; 76 77 /* The string table. May be NULL. Read by 78 _bfd_coff_read_string_table. */ 79 char *strings; 80 /* If this is TRUE, the strings may not be freed. */ 81 bfd_boolean keep_strings; 82 /* If this is TRUE, the strings have been written out already. */ 83 bfd_boolean strings_written; 84 85 /* Is this a PE format coff file? */ 86 int pe; 87 /* Used by the COFF backend linker. */ 88 struct coff_link_hash_entry **sym_hashes; 89 90 /* Used by the pe linker for PowerPC. */ 91 int *local_toc_sym_map; 92 93 struct bfd_link_info *link_info; 94 95 /* Used by coff_find_nearest_line. */ 96 void * line_info; 97 98 /* A place to stash dwarf2 info for this bfd. */ 99 void * dwarf2_find_line_info; 100 101 /* The timestamp from the COFF file header. */ 102 long timestamp; 103 104 /* Copy of some of the f_flags bits in the COFF filehdr structure, 105 used by ARM code. */ 106 flagword flags; 107 108 /* coff-stgo32 EXE stub header after BFD tdata has been allocated. Its data 109 is kept in internal_filehdr.go32stub beforehand. */ 110 char *go32stub; 111 } coff_data_type; 112 113 /* Tdata for pe image files. */ 114 typedef struct pe_tdata 115 { 116 coff_data_type coff; 117 struct internal_extra_pe_aouthdr pe_opthdr; 118 int dll; 119 int has_reloc_section; 120 int dont_strip_reloc; 121 bfd_boolean (*in_reloc_p) (bfd *, reloc_howto_type *); 122 flagword real_flags; 123 } pe_data_type; 124 125 #define pe_data(bfd) ((bfd)->tdata.pe_obj_data) 126 127 /* Tdata for XCOFF files. */ 128 129 struct xcoff_tdata 130 { 131 /* Basic COFF information. */ 132 coff_data_type coff; 133 134 /* TRUE if this is an XCOFF64 file. */ 135 bfd_boolean xcoff64; 136 137 /* TRUE if a large a.out header should be generated. */ 138 bfd_boolean full_aouthdr; 139 140 /* TOC value. */ 141 bfd_vma toc; 142 143 /* Index of section holding TOC. */ 144 int sntoc; 145 146 /* Index of section holding entry point. */ 147 int snentry; 148 149 /* .text alignment from optional header. */ 150 int text_align_power; 151 152 /* .data alignment from optional header. */ 153 int data_align_power; 154 155 /* modtype from optional header. */ 156 short modtype; 157 158 /* cputype from optional header. */ 159 short cputype; 160 161 /* maxdata from optional header. */ 162 bfd_vma maxdata; 163 164 /* maxstack from optional header. */ 165 bfd_vma maxstack; 166 167 /* Used by the XCOFF backend linker. */ 168 asection **csects; 169 long *debug_indices; 170 unsigned int *lineno_counts; 171 unsigned int import_file_id; 172 }; 173 174 #define xcoff_data(abfd) ((abfd)->tdata.xcoff_obj_data) 175 176 /* We take the address of the first element of an asymbol to ensure that the 177 macro is only ever applied to an asymbol. */ 178 #define coffsymbol(asymbol) ((coff_symbol_type *)(&((asymbol)->the_bfd))) 179 180 /* The used_by_bfd field of a section may be set to a pointer to this 181 structure. */ 182 183 struct coff_section_tdata 184 { 185 /* The relocs, swapped into COFF internal form. This may be NULL. */ 186 struct internal_reloc *relocs; 187 /* If this is TRUE, the relocs entry may not be freed. */ 188 bfd_boolean keep_relocs; 189 /* The section contents. This may be NULL. */ 190 bfd_byte *contents; 191 /* If this is TRUE, the contents entry may not be freed. */ 192 bfd_boolean keep_contents; 193 /* Information cached by coff_find_nearest_line. */ 194 bfd_vma offset; 195 unsigned int i; 196 const char *function; 197 /* Optional information about a COMDAT entry; NULL if not COMDAT. */ 198 struct coff_comdat_info *comdat; 199 int line_base; 200 /* A pointer used for .stab linking optimizations. */ 201 void * stab_info; 202 /* Available for individual backends. */ 203 void * tdata; 204 }; 205 206 /* An accessor macro for the coff_section_tdata structure. */ 207 #define coff_section_data(abfd, sec) \ 208 ((struct coff_section_tdata *) (sec)->used_by_bfd) 209 210 /* Tdata for sections in XCOFF files. This is used by the linker. */ 211 212 struct xcoff_section_tdata 213 { 214 /* Used for XCOFF csects created by the linker; points to the real 215 XCOFF section which contains this csect. */ 216 asection *enclosing; 217 /* The lineno_count field for the enclosing section, because we are 218 going to clobber it there. */ 219 unsigned int lineno_count; 220 /* The first and last symbol indices for symbols used by this csect. */ 221 unsigned long first_symndx; 222 unsigned long last_symndx; 223 }; 224 225 /* An accessor macro the xcoff_section_tdata structure. */ 226 #define xcoff_section_data(abfd, sec) \ 227 ((struct xcoff_section_tdata *) coff_section_data ((abfd), (sec))->tdata) 228 229 /* Tdata for sections in PE files. */ 230 231 struct pei_section_tdata 232 { 233 /* The virtual size of the section. */ 234 bfd_size_type virt_size; 235 /* The PE section flags. */ 236 long pe_flags; 237 }; 238 239 /* An accessor macro for the pei_section_tdata structure. */ 240 #define pei_section_data(abfd, sec) \ 241 ((struct pei_section_tdata *) coff_section_data ((abfd), (sec))->tdata) 242 243 /* COFF linker hash table entries. */ 244 245 struct coff_link_hash_entry 246 { 247 struct bfd_link_hash_entry root; 248 249 /* Symbol index in output file. Set to -1 initially. Set to -2 if 250 there is a reloc against this symbol. */ 251 long indx; 252 253 /* Symbol type. */ 254 unsigned short type; 255 256 /* Symbol class. */ 257 unsigned char symbol_class; 258 259 /* Number of auxiliary entries. */ 260 char numaux; 261 262 /* BFD to take auxiliary entries from. */ 263 bfd *auxbfd; 264 265 /* Pointer to array of auxiliary entries, if any. */ 266 union internal_auxent *aux; 267 268 /* Flag word; legal values follow. */ 269 unsigned short coff_link_hash_flags; 270 /* Symbol is a PE section symbol. */ 271 #define COFF_LINK_HASH_PE_SECTION_SYMBOL (01) 272 }; 273 274 /* COFF linker hash table. */ 275 276 struct coff_link_hash_table 277 { 278 struct bfd_link_hash_table root; 279 /* A pointer to information used to link stabs in sections. */ 280 struct stab_info stab_info; 281 }; 282 283 /* Look up an entry in a COFF linker hash table. */ 284 285 #define coff_link_hash_lookup(table, string, create, copy, follow) \ 286 ((struct coff_link_hash_entry *) \ 287 bfd_link_hash_lookup (&(table)->root, (string), (create), \ 288 (copy), (follow))) 289 290 /* Traverse a COFF linker hash table. */ 291 292 #define coff_link_hash_traverse(table, func, info) \ 293 (bfd_link_hash_traverse \ 294 (&(table)->root, \ 295 (bfd_boolean (*) (struct bfd_link_hash_entry *, void *)) (func), \ 296 (info))) 297 298 /* Get the COFF linker hash table from a link_info structure. */ 299 300 #define coff_hash_table(p) ((struct coff_link_hash_table *) ((p)->hash)) 301 302 /* Functions in coffgen.c. */ 303 extern const bfd_target *coff_object_p 304 (bfd *); 305 extern struct bfd_section *coff_section_from_bfd_index 306 (bfd *, int); 307 extern long coff_get_symtab_upper_bound 308 (bfd *); 309 extern long coff_canonicalize_symtab 310 (bfd *, asymbol **); 311 extern int coff_count_linenumbers 312 (bfd *); 313 extern struct coff_symbol_struct *coff_symbol_from 314 (bfd *, asymbol *); 315 extern bfd_boolean coff_renumber_symbols 316 (bfd *, int *); 317 extern void coff_mangle_symbols 318 (bfd *); 319 extern bfd_boolean coff_write_symbols 320 (bfd *); 321 extern bfd_boolean coff_write_alien_symbol 322 (bfd *, asymbol *, struct internal_syment *, bfd_vma *, 323 bfd_size_type *, asection **, bfd_size_type *); 324 extern bfd_boolean coff_write_linenumbers 325 (bfd *); 326 extern alent *coff_get_lineno 327 (bfd *, asymbol *); 328 extern asymbol *coff_section_symbol 329 (bfd *, char *); 330 extern bfd_boolean _bfd_coff_get_external_symbols 331 (bfd *); 332 extern const char *_bfd_coff_read_string_table 333 (bfd *); 334 extern bfd_boolean _bfd_coff_free_symbols 335 (bfd *); 336 extern struct coff_ptr_struct *coff_get_normalized_symtab 337 (bfd *); 338 extern long coff_get_reloc_upper_bound 339 (bfd *, sec_ptr); 340 extern asymbol *coff_make_empty_symbol 341 (bfd *); 342 extern void coff_print_symbol 343 (bfd *, void * filep, asymbol *, bfd_print_symbol_type); 344 extern void coff_get_symbol_info 345 (bfd *, asymbol *, symbol_info *ret); 346 extern bfd_boolean _bfd_coff_is_local_label_name 347 (bfd *, const char *); 348 extern asymbol *coff_bfd_make_debug_symbol 349 (bfd *, void *, unsigned long); 350 extern bfd_boolean coff_find_nearest_line 351 (bfd *, asection *, asymbol **, bfd_vma, const char **, 352 const char **, unsigned int *); 353 extern bfd_boolean coff_find_nearest_line_discriminator 354 (bfd *, asection *, asymbol **, bfd_vma, const char **, 355 const char **, unsigned int *, unsigned int *); 356 struct dwarf_debug_section; 357 extern bfd_boolean coff_find_nearest_line_with_names 358 (bfd *, const struct dwarf_debug_section *, asection *, asymbol **, 359 bfd_vma, const char **, const char **, unsigned int *); 360 extern bfd_boolean coff_find_inliner_info 361 (bfd *, const char **, const char **, unsigned int *); 362 extern int coff_sizeof_headers 363 (bfd *, struct bfd_link_info *); 364 extern bfd_boolean bfd_coff_reloc16_relax_section 365 (bfd *, asection *, struct bfd_link_info *, bfd_boolean *); 366 extern bfd_byte *bfd_coff_reloc16_get_relocated_section_contents 367 (bfd *, struct bfd_link_info *, struct bfd_link_order *, 368 bfd_byte *, bfd_boolean, asymbol **); 369 extern bfd_vma bfd_coff_reloc16_get_value 370 (arelent *, struct bfd_link_info *, asection *); 371 extern void bfd_perform_slip 372 (bfd *, unsigned int, asection *, bfd_vma); 373 374 /* Functions and types in cofflink.c. */ 375 376 #define STRING_SIZE_SIZE 4 377 378 /* We use a hash table to merge identical enum, struct, and union 379 definitions in the linker. */ 380 381 /* Information we keep for a single element (an enum value, a 382 structure or union field) in the debug merge hash table. */ 383 384 struct coff_debug_merge_element 385 { 386 /* Next element. */ 387 struct coff_debug_merge_element *next; 388 389 /* Name. */ 390 const char *name; 391 392 /* Type. */ 393 unsigned int type; 394 395 /* Symbol index for complex type. */ 396 long tagndx; 397 }; 398 399 /* A linked list of debug merge entries for a given name. */ 400 401 struct coff_debug_merge_type 402 { 403 /* Next type with the same name. */ 404 struct coff_debug_merge_type *next; 405 406 /* Class of type. */ 407 int type_class; 408 409 /* Symbol index where this type is defined. */ 410 long indx; 411 412 /* List of elements. */ 413 struct coff_debug_merge_element *elements; 414 }; 415 416 /* Information we store in the debug merge hash table. */ 417 418 struct coff_debug_merge_hash_entry 419 { 420 struct bfd_hash_entry root; 421 422 /* A list of types with this name. */ 423 struct coff_debug_merge_type *types; 424 }; 425 426 /* The debug merge hash table. */ 427 428 struct coff_debug_merge_hash_table 429 { 430 struct bfd_hash_table root; 431 }; 432 433 /* Initialize a COFF debug merge hash table. */ 434 435 #define coff_debug_merge_hash_table_init(table) \ 436 (bfd_hash_table_init (&(table)->root, _bfd_coff_debug_merge_hash_newfunc, \ 437 sizeof (struct coff_debug_merge_hash_entry))) 438 439 /* Free a COFF debug merge hash table. */ 440 441 #define coff_debug_merge_hash_table_free(table) \ 442 (bfd_hash_table_free (&(table)->root)) 443 444 /* Look up an entry in a COFF debug merge hash table. */ 445 446 #define coff_debug_merge_hash_lookup(table, string, create, copy) \ 447 ((struct coff_debug_merge_hash_entry *) \ 448 bfd_hash_lookup (&(table)->root, (string), (create), (copy))) 449 450 /* Information we keep for each section in the output file when doing 451 a relocatable link. */ 452 453 struct coff_link_section_info 454 { 455 /* The relocs to be output. */ 456 struct internal_reloc *relocs; 457 /* For each reloc against a global symbol whose index was not known 458 when the reloc was handled, the global hash table entry. */ 459 struct coff_link_hash_entry **rel_hashes; 460 }; 461 462 /* Information that we pass around while doing the final link step. */ 463 464 struct coff_final_link_info 465 { 466 /* General link information. */ 467 struct bfd_link_info *info; 468 /* Output BFD. */ 469 bfd *output_bfd; 470 /* Used to indicate failure in traversal routine. */ 471 bfd_boolean failed; 472 /* If doing "task linking" set only during the time when we want the 473 global symbol writer to convert the storage class of defined global 474 symbols from global to static. */ 475 bfd_boolean global_to_static; 476 /* Hash table for long symbol names. */ 477 struct bfd_strtab_hash *strtab; 478 /* When doing a relocatable link, an array of information kept for 479 each output section, indexed by the target_index field. */ 480 struct coff_link_section_info *section_info; 481 /* Symbol index of last C_FILE symbol (-1 if none). */ 482 long last_file_index; 483 /* Contents of last C_FILE symbol. */ 484 struct internal_syment last_file; 485 /* Symbol index of first aux entry of last .bf symbol with an empty 486 endndx field (-1 if none). */ 487 long last_bf_index; 488 /* Contents of last_bf_index aux entry. */ 489 union internal_auxent last_bf; 490 /* Hash table used to merge debug information. */ 491 struct coff_debug_merge_hash_table debug_merge; 492 /* Buffer large enough to hold swapped symbols of any input file. */ 493 struct internal_syment *internal_syms; 494 /* Buffer large enough to hold sections of symbols of any input file. */ 495 asection **sec_ptrs; 496 /* Buffer large enough to hold output indices of symbols of any 497 input file. */ 498 long *sym_indices; 499 /* Buffer large enough to hold output symbols for any input file. */ 500 bfd_byte *outsyms; 501 /* Buffer large enough to hold external line numbers for any input 502 section. */ 503 bfd_byte *linenos; 504 /* Buffer large enough to hold any input section. */ 505 bfd_byte *contents; 506 /* Buffer large enough to hold external relocs of any input section. */ 507 bfd_byte *external_relocs; 508 /* Buffer large enough to hold swapped relocs of any input section. */ 509 struct internal_reloc *internal_relocs; 510 }; 511 512 /* Most COFF variants have no way to record the alignment of a 513 section. This struct is used to set a specific alignment based on 514 the name of the section. */ 515 516 struct coff_section_alignment_entry 517 { 518 /* The section name. */ 519 const char *name; 520 521 /* This is either (unsigned int) -1, indicating that the section 522 name must match exactly, or it is the number of letters which 523 must match at the start of the name. */ 524 unsigned int comparison_length; 525 526 /* These macros may be used to fill in the first two fields in a 527 structure initialization. */ 528 #define COFF_SECTION_NAME_EXACT_MATCH(name) (name), ((unsigned int) -1) 529 #define COFF_SECTION_NAME_PARTIAL_MATCH(name) (name), (sizeof (name) - 1) 530 531 /* Only use this entry if the default section alignment for this 532 target is at least that much (as a power of two). If this field 533 is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored. */ 534 unsigned int default_alignment_min; 535 536 /* Only use this entry if the default section alignment for this 537 target is no greater than this (as a power of two). If this 538 field is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored. */ 539 unsigned int default_alignment_max; 540 541 #define COFF_ALIGNMENT_FIELD_EMPTY ((unsigned int) -1) 542 543 /* The desired alignment for this section (as a power of two). */ 544 unsigned int alignment_power; 545 }; 546 547 extern struct bfd_hash_entry *_bfd_coff_link_hash_newfunc 548 (struct bfd_hash_entry *, struct bfd_hash_table *, const char *); 549 extern bfd_boolean _bfd_coff_link_hash_table_init 550 (struct coff_link_hash_table *, bfd *, 551 struct bfd_hash_entry *(*) (struct bfd_hash_entry *, 552 struct bfd_hash_table *, 553 const char *), 554 unsigned int); 555 extern struct bfd_link_hash_table *_bfd_coff_link_hash_table_create 556 (bfd *); 557 extern const char *_bfd_coff_internal_syment_name 558 (bfd *, const struct internal_syment *, char *); 559 extern bfd_boolean _bfd_coff_section_already_linked 560 (bfd *, asection *, struct bfd_link_info *); 561 extern bfd_boolean _bfd_coff_link_add_symbols 562 (bfd *, struct bfd_link_info *); 563 extern bfd_boolean _bfd_coff_final_link 564 (bfd *, struct bfd_link_info *); 565 extern struct internal_reloc *_bfd_coff_read_internal_relocs 566 (bfd *, asection *, bfd_boolean, bfd_byte *, bfd_boolean, 567 struct internal_reloc *); 568 extern bfd_boolean _bfd_coff_generic_relocate_section 569 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *, 570 struct internal_reloc *, struct internal_syment *, asection **); 571 extern struct bfd_hash_entry *_bfd_coff_debug_merge_hash_newfunc 572 (struct bfd_hash_entry *, struct bfd_hash_table *, const char *); 573 extern bfd_boolean _bfd_coff_write_global_sym 574 (struct bfd_hash_entry *, void *); 575 extern bfd_boolean _bfd_coff_write_task_globals 576 (struct coff_link_hash_entry *, void *); 577 extern bfd_boolean _bfd_coff_link_input_bfd 578 (struct coff_final_link_info *, bfd *); 579 extern bfd_boolean _bfd_coff_reloc_link_order 580 (bfd *, struct coff_final_link_info *, asection *, 581 struct bfd_link_order *); 582 583 584 #define coff_get_section_contents_in_window \ 585 _bfd_generic_get_section_contents_in_window 586 587 /* Functions in xcofflink.c. */ 588 589 extern long _bfd_xcoff_get_dynamic_symtab_upper_bound 590 (bfd *); 591 extern long _bfd_xcoff_canonicalize_dynamic_symtab 592 (bfd *, asymbol **); 593 extern long _bfd_xcoff_get_dynamic_reloc_upper_bound 594 (bfd *); 595 extern long _bfd_xcoff_canonicalize_dynamic_reloc 596 (bfd *, arelent **, asymbol **); 597 extern struct bfd_link_hash_table *_bfd_xcoff_bfd_link_hash_table_create 598 (bfd *); 599 extern void _bfd_xcoff_bfd_link_hash_table_free 600 (struct bfd_link_hash_table *); 601 extern bfd_boolean _bfd_xcoff_bfd_link_add_symbols 602 (bfd *, struct bfd_link_info *); 603 extern bfd_boolean _bfd_xcoff_bfd_final_link 604 (bfd *, struct bfd_link_info *); 605 extern bfd_boolean _bfd_xcoff_define_common_symbol 606 (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *); 607 extern bfd_boolean _bfd_ppc_xcoff_relocate_section 608 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *, 609 struct internal_reloc *, struct internal_syment *, asection **); 610 611 /* Functions in coff-ppc.c. FIXME: These are called by pe.em in the 612 linker, and so should start with bfd and be declared in bfd.h. */ 613 614 extern bfd_boolean ppc_allocate_toc_section 615 (struct bfd_link_info *); 616 extern bfd_boolean ppc_process_before_allocation 617 (bfd *, struct bfd_link_info *); 618