1// target-reloc.h -- target specific relocation support -*- C++ -*- 2 3// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. 4// Written by Ian Lance Taylor <iant@google.com>. 5 6// This file is part of gold. 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 3 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., 51 Franklin Street - Fifth Floor, Boston, 21// MA 02110-1301, USA. 22 23#ifndef GOLD_TARGET_RELOC_H 24#define GOLD_TARGET_RELOC_H 25 26#include "elfcpp.h" 27#include "symtab.h" 28#include "object.h" 29#include "reloc.h" 30#include "reloc-types.h" 31 32namespace gold 33{ 34 35// This function implements the generic part of reloc scanning. The 36// template parameter Scan must be a class type which provides two 37// functions: local() and global(). Those functions implement the 38// machine specific part of scanning. We do it this way to 39// avoidmaking a function call for each relocation, and to avoid 40// repeating the generic code for each target. 41 42template<int size, bool big_endian, typename Target_type, int sh_type, 43 typename Scan> 44inline void 45scan_relocs( 46 Symbol_table* symtab, 47 Layout* layout, 48 Target_type* target, 49 Sized_relobj<size, big_endian>* object, 50 unsigned int data_shndx, 51 const unsigned char* prelocs, 52 size_t reloc_count, 53 Output_section* output_section, 54 bool needs_special_offset_handling, 55 size_t local_count, 56 const unsigned char* plocal_syms) 57{ 58 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype; 59 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size; 60 const int sym_size = elfcpp::Elf_sizes<size>::sym_size; 61 Scan scan; 62 63 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size) 64 { 65 Reltype reloc(prelocs); 66 67 if (needs_special_offset_handling 68 && !output_section->is_input_address_mapped(object, data_shndx, 69 reloc.get_r_offset())) 70 continue; 71 72 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info(); 73 unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info); 74 unsigned int r_type = elfcpp::elf_r_type<size>(r_info); 75 76 if (r_sym < local_count) 77 { 78 gold_assert(plocal_syms != NULL); 79 typename elfcpp::Sym<size, big_endian> lsym(plocal_syms 80 + r_sym * sym_size); 81 unsigned int shndx = lsym.get_st_shndx(); 82 bool is_ordinary; 83 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary); 84 if (is_ordinary 85 && shndx != elfcpp::SHN_UNDEF 86 && !object->is_section_included(shndx) 87 && !symtab->is_section_folded(object, shndx)) 88 { 89 // RELOC is a relocation against a local symbol in a 90 // section we are discarding. We can ignore this 91 // relocation. It will eventually become a reloc 92 // against the value zero. 93 // 94 // FIXME: We should issue a warning if this is an 95 // allocated section; is this the best place to do it? 96 // 97 // FIXME: The old GNU linker would in some cases look 98 // for the linkonce section which caused this section to 99 // be discarded, and, if the other section was the same 100 // size, change the reloc to refer to the other section. 101 // That seems risky and weird to me, and I don't know of 102 // any case where it is actually required. 103 104 continue; 105 } 106 scan.local(symtab, layout, target, object, data_shndx, 107 output_section, reloc, r_type, lsym); 108 } 109 else 110 { 111 Symbol* gsym = object->global_symbol(r_sym); 112 gold_assert(gsym != NULL); 113 if (gsym->is_forwarder()) 114 gsym = symtab->resolve_forwards(gsym); 115 116 scan.global(symtab, layout, target, object, data_shndx, 117 output_section, reloc, r_type, gsym); 118 } 119 } 120} 121 122// Behavior for relocations to discarded comdat sections. 123 124enum Comdat_behavior 125{ 126 CB_UNDETERMINED, // Not yet determined -- need to look at section name. 127 CB_PRETEND, // Attempt to map to the corresponding kept section. 128 CB_IGNORE, // Ignore the relocation. 129 CB_WARNING // Print a warning. 130}; 131 132// Decide what the linker should do for relocations that refer to discarded 133// comdat sections. This decision is based on the name of the section being 134// relocated. 135 136inline Comdat_behavior 137get_comdat_behavior(const char* name) 138{ 139 if (Layout::is_debug_info_section(name)) 140 return CB_PRETEND; 141 if (strcmp(name, ".eh_frame") == 0 142 || strcmp(name, ".gcc_except_table") == 0) 143 return CB_IGNORE; 144 return CB_WARNING; 145} 146 147// Give an error for a symbol with non-default visibility which is not 148// defined locally. 149 150inline void 151visibility_error(const Symbol* sym) 152{ 153 const char* v; 154 switch (sym->visibility()) 155 { 156 case elfcpp::STV_INTERNAL: 157 v = _("internal"); 158 break; 159 case elfcpp::STV_HIDDEN: 160 v = _("hidden"); 161 break; 162 case elfcpp::STV_PROTECTED: 163 v = _("protected"); 164 break; 165 default: 166 gold_unreachable(); 167 } 168 gold_error(_("%s symbol '%s' is not defined locally"), 169 v, sym->name()); 170} 171 172// This function implements the generic part of relocation processing. 173// The template parameter Relocate must be a class type which provides 174// a single function, relocate(), which implements the machine 175// specific part of a relocation. 176 177// SIZE is the ELF size: 32 or 64. BIG_ENDIAN is the endianness of 178// the data. SH_TYPE is the section type: SHT_REL or SHT_RELA. 179// RELOCATE implements operator() to do a relocation. 180 181// PRELOCS points to the relocation data. RELOC_COUNT is the number 182// of relocs. OUTPUT_SECTION is the output section. 183// NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be 184// mapped to output offsets. 185 186// VIEW is the section data, VIEW_ADDRESS is its memory address, and 187// VIEW_SIZE is the size. These refer to the input section, unless 188// NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to 189// the output section. 190 191// RELOC_SYMBOL_CHANGES is used for -fsplit-stack support. If it is 192// not NULL, it is a vector indexed by relocation index. If that 193// entry is not NULL, it points to a global symbol which used as the 194// symbol for the relocation, ignoring the symbol index in the 195// relocation. 196 197template<int size, bool big_endian, typename Target_type, int sh_type, 198 typename Relocate> 199inline void 200relocate_section( 201 const Relocate_info<size, big_endian>* relinfo, 202 Target_type* target, 203 const unsigned char* prelocs, 204 size_t reloc_count, 205 Output_section* output_section, 206 bool needs_special_offset_handling, 207 unsigned char* view, 208 typename elfcpp::Elf_types<size>::Elf_Addr view_address, 209 section_size_type view_size, 210 const Reloc_symbol_changes* reloc_symbol_changes) 211{ 212 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype; 213 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size; 214 Relocate relocate; 215 216 Sized_relobj<size, big_endian>* object = relinfo->object; 217 unsigned int local_count = object->local_symbol_count(); 218 219 Comdat_behavior comdat_behavior = CB_UNDETERMINED; 220 221 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size) 222 { 223 Reltype reloc(prelocs); 224 225 section_offset_type offset = 226 convert_to_section_size_type(reloc.get_r_offset()); 227 228 if (needs_special_offset_handling) 229 { 230 offset = output_section->output_offset(relinfo->object, 231 relinfo->data_shndx, 232 offset); 233 if (offset == -1) 234 continue; 235 } 236 237 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info(); 238 unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info); 239 unsigned int r_type = elfcpp::elf_r_type<size>(r_info); 240 241 const Sized_symbol<size>* sym; 242 243 Symbol_value<size> symval; 244 const Symbol_value<size> *psymval; 245 bool is_defined_in_discarded_section; 246 unsigned int shndx; 247 if (r_sym < local_count 248 && (reloc_symbol_changes == NULL 249 || (*reloc_symbol_changes)[i] == NULL)) 250 { 251 sym = NULL; 252 psymval = object->local_symbol(r_sym); 253 254 // If the local symbol belongs to a section we are discarding, 255 // and that section is a debug section, try to find the 256 // corresponding kept section and map this symbol to its 257 // counterpart in the kept section. The symbol must not 258 // correspond to a section we are folding. 259 bool is_ordinary; 260 shndx = psymval->input_shndx(&is_ordinary); 261 is_defined_in_discarded_section = 262 (is_ordinary 263 && shndx != elfcpp::SHN_UNDEF 264 && !object->is_section_included(shndx) 265 && !relinfo->symtab->is_section_folded(object, shndx)); 266 } 267 else 268 { 269 const Symbol* gsym; 270 if (reloc_symbol_changes != NULL 271 && (*reloc_symbol_changes)[i] != NULL) 272 gsym = (*reloc_symbol_changes)[i]; 273 else 274 { 275 gsym = object->global_symbol(r_sym); 276 gold_assert(gsym != NULL); 277 if (gsym->is_forwarder()) 278 gsym = relinfo->symtab->resolve_forwards(gsym); 279 } 280 281 sym = static_cast<const Sized_symbol<size>*>(gsym); 282 if (sym->has_symtab_index() && sym->symtab_index() != -1U) 283 symval.set_output_symtab_index(sym->symtab_index()); 284 else 285 symval.set_no_output_symtab_entry(); 286 symval.set_output_value(sym->value()); 287 if (gsym->type() == elfcpp::STT_TLS) 288 symval.set_is_tls_symbol(); 289 else if (gsym->type() == elfcpp::STT_GNU_IFUNC) 290 symval.set_is_ifunc_symbol(); 291 psymval = &symval; 292 293 is_defined_in_discarded_section = 294 (gsym->is_defined_in_discarded_section() 295 && gsym->is_undefined()); 296 shndx = 0; 297 } 298 299 Symbol_value<size> symval2; 300 if (is_defined_in_discarded_section) 301 { 302 if (comdat_behavior == CB_UNDETERMINED) 303 { 304 std::string name = object->section_name(relinfo->data_shndx); 305 comdat_behavior = get_comdat_behavior(name.c_str()); 306 } 307 if (comdat_behavior == CB_PRETEND) 308 { 309 // FIXME: This case does not work for global symbols. 310 // We have no place to store the original section index. 311 // Fortunately this does not matter for comdat sections, 312 // only for sections explicitly discarded by a linker 313 // script. 314 bool found; 315 typename elfcpp::Elf_types<size>::Elf_Addr value = 316 object->map_to_kept_section(shndx, &found); 317 if (found) 318 symval2.set_output_value(value + psymval->input_value()); 319 else 320 symval2.set_output_value(0); 321 } 322 else 323 { 324 if (comdat_behavior == CB_WARNING) 325 gold_warning_at_location(relinfo, i, offset, 326 _("relocation refers to discarded " 327 "section")); 328 symval2.set_output_value(0); 329 } 330 symval2.set_no_output_symtab_entry(); 331 psymval = &symval2; 332 } 333 334 if (!relocate.relocate(relinfo, target, output_section, i, reloc, 335 r_type, sym, psymval, view + offset, 336 view_address + offset, view_size)) 337 continue; 338 339 if (offset < 0 || static_cast<section_size_type>(offset) >= view_size) 340 { 341 gold_error_at_location(relinfo, i, offset, 342 _("reloc has bad offset %zu"), 343 static_cast<size_t>(offset)); 344 continue; 345 } 346 347 if (sym != NULL 348 && (sym->is_undefined() || sym->is_placeholder()) 349 && sym->binding() != elfcpp::STB_WEAK 350 && !is_defined_in_discarded_section 351 && !target->is_defined_by_abi(sym) 352 && (!parameters->options().shared() // -shared 353 || parameters->options().defs())) // -z defs 354 gold_undefined_symbol_at_location(sym, relinfo, i, offset); 355 else if (sym != NULL 356 && sym->visibility() != elfcpp::STV_DEFAULT 357 && (sym->is_undefined() || sym->is_from_dynobj())) 358 visibility_error(sym); 359 360 if (sym != NULL && sym->has_warning()) 361 relinfo->symtab->issue_warning(sym, relinfo, i, offset); 362 } 363} 364 365// This class may be used as a typical class for the 366// Scan_relocatable_reloc parameter to scan_relocatable_relocs. The 367// template parameter Classify_reloc must be a class type which 368// provides a function get_size_for_reloc which returns the number of 369// bytes to which a reloc applies. This class is intended to capture 370// the most typical target behaviour, while still permitting targets 371// to define their own independent class for Scan_relocatable_reloc. 372 373template<int sh_type, typename Classify_reloc> 374class Default_scan_relocatable_relocs 375{ 376 public: 377 // Return the strategy to use for a local symbol which is not a 378 // section symbol, given the relocation type. 379 inline Relocatable_relocs::Reloc_strategy 380 local_non_section_strategy(unsigned int r_type, Relobj*, unsigned int r_sym) 381 { 382 // We assume that relocation type 0 is NONE. Targets which are 383 // different must override. 384 if (r_type == 0 && r_sym == 0) 385 return Relocatable_relocs::RELOC_DISCARD; 386 return Relocatable_relocs::RELOC_COPY; 387 } 388 389 // Return the strategy to use for a local symbol which is a section 390 // symbol, given the relocation type. 391 inline Relocatable_relocs::Reloc_strategy 392 local_section_strategy(unsigned int r_type, Relobj* object) 393 { 394 if (sh_type == elfcpp::SHT_RELA) 395 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA; 396 else 397 { 398 Classify_reloc classify; 399 switch (classify.get_size_for_reloc(r_type, object)) 400 { 401 case 0: 402 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0; 403 case 1: 404 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1; 405 case 2: 406 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2; 407 case 4: 408 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4; 409 case 8: 410 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8; 411 default: 412 gold_unreachable(); 413 } 414 } 415 } 416 417 // Return the strategy to use for a global symbol, given the 418 // relocation type, the object, and the symbol index. 419 inline Relocatable_relocs::Reloc_strategy 420 global_strategy(unsigned int, Relobj*, unsigned int) 421 { return Relocatable_relocs::RELOC_COPY; } 422}; 423 424// Scan relocs during a relocatable link. This is a default 425// definition which should work for most targets. 426// Scan_relocatable_reloc must name a class type which provides three 427// functions which return a Relocatable_relocs::Reloc_strategy code: 428// global_strategy, local_non_section_strategy, and 429// local_section_strategy. Most targets should be able to use 430// Default_scan_relocatable_relocs as this class. 431 432template<int size, bool big_endian, int sh_type, 433 typename Scan_relocatable_reloc> 434void 435scan_relocatable_relocs( 436 Symbol_table*, 437 Layout*, 438 Sized_relobj<size, big_endian>* object, 439 unsigned int data_shndx, 440 const unsigned char* prelocs, 441 size_t reloc_count, 442 Output_section* output_section, 443 bool needs_special_offset_handling, 444 size_t local_symbol_count, 445 const unsigned char* plocal_syms, 446 Relocatable_relocs* rr) 447{ 448 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype; 449 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size; 450 const int sym_size = elfcpp::Elf_sizes<size>::sym_size; 451 Scan_relocatable_reloc scan; 452 453 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size) 454 { 455 Reltype reloc(prelocs); 456 457 Relocatable_relocs::Reloc_strategy strategy; 458 459 if (needs_special_offset_handling 460 && !output_section->is_input_address_mapped(object, data_shndx, 461 reloc.get_r_offset())) 462 strategy = Relocatable_relocs::RELOC_DISCARD; 463 else 464 { 465 typename elfcpp::Elf_types<size>::Elf_WXword r_info = 466 reloc.get_r_info(); 467 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info); 468 const unsigned int r_type = elfcpp::elf_r_type<size>(r_info); 469 470 if (r_sym >= local_symbol_count) 471 strategy = scan.global_strategy(r_type, object, r_sym); 472 else 473 { 474 gold_assert(plocal_syms != NULL); 475 typename elfcpp::Sym<size, big_endian> lsym(plocal_syms 476 + r_sym * sym_size); 477 unsigned int shndx = lsym.get_st_shndx(); 478 bool is_ordinary; 479 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary); 480 if (is_ordinary 481 && shndx != elfcpp::SHN_UNDEF 482 && !object->is_section_included(shndx)) 483 { 484 // RELOC is a relocation against a local symbol 485 // defined in a section we are discarding. Discard 486 // the reloc. FIXME: Should we issue a warning? 487 strategy = Relocatable_relocs::RELOC_DISCARD; 488 } 489 else if (lsym.get_st_type() != elfcpp::STT_SECTION) 490 strategy = scan.local_non_section_strategy(r_type, object, 491 r_sym); 492 else 493 { 494 strategy = scan.local_section_strategy(r_type, object); 495 if (strategy != Relocatable_relocs::RELOC_DISCARD) 496 object->output_section(shndx)->set_needs_symtab_index(); 497 } 498 499 if (strategy == Relocatable_relocs::RELOC_COPY) 500 object->set_must_have_output_symtab_entry(r_sym); 501 } 502 } 503 504 rr->set_next_reloc_strategy(strategy); 505 } 506} 507 508// Relocate relocs during a relocatable link. This is a default 509// definition which should work for most targets. 510 511template<int size, bool big_endian, int sh_type> 512void 513relocate_for_relocatable( 514 const Relocate_info<size, big_endian>* relinfo, 515 const unsigned char* prelocs, 516 size_t reloc_count, 517 Output_section* output_section, 518 typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section, 519 const Relocatable_relocs* rr, 520 unsigned char* view, 521 typename elfcpp::Elf_types<size>::Elf_Addr view_address, 522 section_size_type view_size, 523 unsigned char* reloc_view, 524 section_size_type reloc_view_size) 525{ 526 typedef typename elfcpp::Elf_types<size>::Elf_Addr Address; 527 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype; 528 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc_write 529 Reltype_write; 530 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size; 531 const Address invalid_address = static_cast<Address>(0) - 1; 532 533 Sized_relobj<size, big_endian>* const object = relinfo->object; 534 const unsigned int local_count = object->local_symbol_count(); 535 536 unsigned char* pwrite = reloc_view; 537 538 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size) 539 { 540 Relocatable_relocs::Reloc_strategy strategy = rr->strategy(i); 541 if (strategy == Relocatable_relocs::RELOC_DISCARD) 542 continue; 543 544 if (strategy == Relocatable_relocs::RELOC_SPECIAL) 545 { 546 // Target wants to handle this relocation. 547 Sized_target<size, big_endian>* target = 548 parameters->sized_target<size, big_endian>(); 549 target->relocate_special_relocatable(relinfo, sh_type, prelocs, 550 i, output_section, 551 offset_in_output_section, 552 view, view_address, 553 view_size, pwrite); 554 pwrite += reloc_size; 555 continue; 556 } 557 Reltype reloc(prelocs); 558 Reltype_write reloc_write(pwrite); 559 560 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info(); 561 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info); 562 const unsigned int r_type = elfcpp::elf_r_type<size>(r_info); 563 564 // Get the new symbol index. 565 566 unsigned int new_symndx; 567 if (r_sym < local_count) 568 { 569 switch (strategy) 570 { 571 case Relocatable_relocs::RELOC_COPY: 572 if (r_sym == 0) 573 new_symndx = 0; 574 else 575 { 576 new_symndx = object->symtab_index(r_sym); 577 gold_assert(new_symndx != -1U); 578 } 579 break; 580 581 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA: 582 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0: 583 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1: 584 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2: 585 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4: 586 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8: 587 { 588 // We are adjusting a section symbol. We need to find 589 // the symbol table index of the section symbol for 590 // the output section corresponding to input section 591 // in which this symbol is defined. 592 gold_assert(r_sym < local_count); 593 bool is_ordinary; 594 unsigned int shndx = 595 object->local_symbol_input_shndx(r_sym, &is_ordinary); 596 gold_assert(is_ordinary); 597 Output_section* os = object->output_section(shndx); 598 gold_assert(os != NULL); 599 gold_assert(os->needs_symtab_index()); 600 new_symndx = os->symtab_index(); 601 } 602 break; 603 604 default: 605 gold_unreachable(); 606 } 607 } 608 else 609 { 610 const Symbol* gsym = object->global_symbol(r_sym); 611 gold_assert(gsym != NULL); 612 if (gsym->is_forwarder()) 613 gsym = relinfo->symtab->resolve_forwards(gsym); 614 615 gold_assert(gsym->has_symtab_index()); 616 new_symndx = gsym->symtab_index(); 617 } 618 619 // Get the new offset--the location in the output section where 620 // this relocation should be applied. 621 622 Address offset = reloc.get_r_offset(); 623 Address new_offset; 624 if (offset_in_output_section != invalid_address) 625 new_offset = offset + offset_in_output_section; 626 else 627 { 628 section_offset_type sot_offset = 629 convert_types<section_offset_type, Address>(offset); 630 section_offset_type new_sot_offset = 631 output_section->output_offset(object, relinfo->data_shndx, 632 sot_offset); 633 gold_assert(new_sot_offset != -1); 634 new_offset = new_sot_offset; 635 } 636 637 // In an object file, r_offset is an offset within the section. 638 // In an executable or dynamic object, generated by 639 // --emit-relocs, r_offset is an absolute address. 640 if (!parameters->options().relocatable()) 641 { 642 new_offset += view_address; 643 if (offset_in_output_section != invalid_address) 644 new_offset -= offset_in_output_section; 645 } 646 647 reloc_write.put_r_offset(new_offset); 648 reloc_write.put_r_info(elfcpp::elf_r_info<size>(new_symndx, r_type)); 649 650 // Handle the reloc addend based on the strategy. 651 652 if (strategy == Relocatable_relocs::RELOC_COPY) 653 { 654 if (sh_type == elfcpp::SHT_RELA) 655 Reloc_types<sh_type, size, big_endian>:: 656 copy_reloc_addend(&reloc_write, 657 &reloc); 658 } 659 else 660 { 661 // The relocation uses a section symbol in the input file. 662 // We are adjusting it to use a section symbol in the output 663 // file. The input section symbol refers to some address in 664 // the input section. We need the relocation in the output 665 // file to refer to that same address. This adjustment to 666 // the addend is the same calculation we use for a simple 667 // absolute relocation for the input section symbol. 668 669 const Symbol_value<size>* psymval = object->local_symbol(r_sym); 670 671 unsigned char* padd = view + offset; 672 switch (strategy) 673 { 674 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA: 675 { 676 typename elfcpp::Elf_types<size>::Elf_Swxword addend; 677 addend = Reloc_types<sh_type, size, big_endian>:: 678 get_reloc_addend(&reloc); 679 addend = psymval->value(object, addend); 680 Reloc_types<sh_type, size, big_endian>:: 681 set_reloc_addend(&reloc_write, addend); 682 } 683 break; 684 685 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0: 686 break; 687 688 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1: 689 Relocate_functions<size, big_endian>::rel8(padd, object, 690 psymval); 691 break; 692 693 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2: 694 Relocate_functions<size, big_endian>::rel16(padd, object, 695 psymval); 696 break; 697 698 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4: 699 Relocate_functions<size, big_endian>::rel32(padd, object, 700 psymval); 701 break; 702 703 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8: 704 Relocate_functions<size, big_endian>::rel64(padd, object, 705 psymval); 706 break; 707 708 default: 709 gold_unreachable(); 710 } 711 } 712 713 pwrite += reloc_size; 714 } 715 716 gold_assert(static_cast<section_size_type>(pwrite - reloc_view) 717 == reloc_view_size); 718} 719 720} // End namespace gold. 721 722#endif // !defined(GOLD_TARGET_RELOC_H) 723