* config/tc-mips.c (is_delay_slot_valid): Simplify expression.
[deliverable/binutils-gdb.git] / gold / target-reloc.h
CommitLineData
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1// target-reloc.h -- target specific relocation support -*- C++ -*-
2
191f1a2d 3// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
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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
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23#ifndef GOLD_TARGET_RELOC_H
24#define GOLD_TARGET_RELOC_H
25
26#include "elfcpp.h"
27#include "symtab.h"
364c7fa5 28#include "object.h"
6a74a719 29#include "reloc.h"
c06b7b0b 30#include "reloc-types.h"
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31
32namespace gold
33{
34
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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
9b547ce6 39// avoid making a function call for each relocation, and to avoid
6a74a719 40// repeating the generic code for each target.
92e059d8 41
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42template<int size, bool big_endian, typename Target_type, int sh_type,
43 typename Scan>
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44inline void
45scan_relocs(
92e059d8 46 Symbol_table* symtab,
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47 Layout* layout,
48 Target_type* target,
6fa2a40b 49 Sized_relobj_file<size, big_endian>* object,
a3ad94ed 50 unsigned int data_shndx,
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51 const unsigned char* prelocs,
52 size_t reloc_count,
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53 Output_section* output_section,
54 bool needs_special_offset_handling,
92e059d8 55 size_t local_count,
730cdc88 56 const unsigned char* plocal_syms)
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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
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67 if (needs_special_offset_handling
68 && !output_section->is_input_address_mapped(object, data_shndx,
69 reloc.get_r_offset()))
70 continue;
71
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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 {
a3ad94ed 78 gold_assert(plocal_syms != NULL);
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79 typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
80 + r_sym * sym_size);
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81 unsigned int shndx = lsym.get_st_shndx();
82 bool is_ordinary;
83 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
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84 // If RELOC is a relocation against a local symbol in a
85 // section we are discarding then we can ignore it. It will
86 // eventually become a reloc against the value zero.
87 //
88 // FIXME: We should issue a warning if this is an
89 // allocated section; is this the best place to do it?
90 //
91 // FIXME: The old GNU linker would in some cases look
92 // for the linkonce section which caused this section to
93 // be discarded, and, if the other section was the same
94 // size, change the reloc to refer to the other section.
95 // That seems risky and weird to me, and I don't know of
96 // any case where it is actually required.
97 bool is_discarded = (is_ordinary
98 && shndx != elfcpp::SHN_UNDEF
99 && !object->is_section_included(shndx)
100 && !symtab->is_section_folded(object, shndx));
ad0f2072 101 scan.local(symtab, layout, target, object, data_shndx,
bfdfa4cd 102 output_section, reloc, r_type, lsym, is_discarded);
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103 }
104 else
105 {
730cdc88 106 Symbol* gsym = object->global_symbol(r_sym);
a3ad94ed 107 gold_assert(gsym != NULL);
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108 if (gsym->is_forwarder())
109 gsym = symtab->resolve_forwards(gsym);
110
ad0f2072 111 scan.global(symtab, layout, target, object, data_shndx,
07f397ab 112 output_section, reloc, r_type, gsym);
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113 }
114 }
115}
116
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117// Behavior for relocations to discarded comdat sections.
118
119enum Comdat_behavior
120{
121 CB_UNDETERMINED, // Not yet determined -- need to look at section name.
122 CB_PRETEND, // Attempt to map to the corresponding kept section.
123 CB_IGNORE, // Ignore the relocation.
124 CB_WARNING // Print a warning.
125};
126
168a4726 127class Default_comdat_behavior
e94cf127 128{
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129 public:
130 // Decide what the linker should do for relocations that refer to
131 // discarded comdat sections. This decision is based on the name of
132 // the section being relocated.
133
134 inline Comdat_behavior
135 get(const char* name)
136 {
137 if (Layout::is_debug_info_section(name))
138 return CB_PRETEND;
139 if (strcmp(name, ".eh_frame") == 0
140 || strcmp(name, ".gcc_except_table") == 0)
141 return CB_IGNORE;
142 return CB_WARNING;
143 }
144};
e94cf127 145
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146// Give an error for a symbol with non-default visibility which is not
147// defined locally.
148
149inline void
150visibility_error(const Symbol* sym)
151{
152 const char* v;
153 switch (sym->visibility())
154 {
155 case elfcpp::STV_INTERNAL:
156 v = _("internal");
157 break;
158 case elfcpp::STV_HIDDEN:
159 v = _("hidden");
160 break;
161 case elfcpp::STV_PROTECTED:
162 v = _("protected");
163 break;
164 default:
165 gold_unreachable();
166 }
167 gold_error(_("%s symbol '%s' is not defined locally"),
168 v, sym->name());
169}
170
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171// Return true if we are should issue an error saying that SYM is an
172// undefined symbol. This is called if there is a relocation against
173// SYM.
174
175inline bool
176issue_undefined_symbol_error(const Symbol* sym)
177{
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178 // We only report global symbols.
179 if (sym == NULL)
180 return false;
181
182 // We only report undefined symbols.
183 if (!sym->is_undefined() && !sym->is_placeholder())
184 return false;
185
186 // We don't report weak symbols.
187 if (sym->binding() == elfcpp::STB_WEAK)
188 return false;
189
190 // We don't report symbols defined in discarded sections.
191 if (sym->is_defined_in_discarded_section())
192 return false;
193
194 // If the target defines this symbol, don't report it here.
195 if (parameters->target().is_defined_by_abi(sym))
196 return false;
197
198 // See if we've been told to ignore whether this symbol is
199 // undefined.
200 const char* const u = parameters->options().unresolved_symbols();
201 if (u != NULL)
202 {
203 if (strcmp(u, "ignore-all") == 0)
204 return false;
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205 if (strcmp(u, "report-all") == 0)
206 return true;
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207 if (strcmp(u, "ignore-in-object-files") == 0 && !sym->in_dyn())
208 return false;
209 if (strcmp(u, "ignore-in-shared-libs") == 0 && !sym->in_reg())
210 return false;
211 }
212
213 // When creating a shared library, only report unresolved symbols if
214 // -z defs was used.
215 if (parameters->options().shared() && !parameters->options().defs())
216 return false;
217
218 // Otherwise issue a warning.
219 return true;
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220}
221
92e059d8 222// This function implements the generic part of relocation processing.
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223// The template parameter Relocate must be a class type which provides
224// a single function, relocate(), which implements the machine
225// specific part of a relocation.
61ba1cf9 226
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227// The template parameter Relocate_comdat_behavior is a class type
228// which provides a single function, get(), which determines what the
229// linker should do for relocations that refer to discarded comdat
230// sections.
231
61ba1cf9 232// SIZE is the ELF size: 32 or 64. BIG_ENDIAN is the endianness of
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233// the data. SH_TYPE is the section type: SHT_REL or SHT_RELA.
234// RELOCATE implements operator() to do a relocation.
61ba1cf9 235
92e059d8 236// PRELOCS points to the relocation data. RELOC_COUNT is the number
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237// of relocs. OUTPUT_SECTION is the output section.
238// NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
239// mapped to output offsets.
240
241// VIEW is the section data, VIEW_ADDRESS is its memory address, and
242// VIEW_SIZE is the size. These refer to the input section, unless
243// NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
244// the output section.
61ba1cf9 245
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246// RELOC_SYMBOL_CHANGES is used for -fsplit-stack support. If it is
247// not NULL, it is a vector indexed by relocation index. If that
248// entry is not NULL, it points to a global symbol which used as the
249// symbol for the relocation, ignoring the symbol index in the
250// relocation.
251
ead1e424 252template<int size, bool big_endian, typename Target_type, int sh_type,
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253 typename Relocate,
254 typename Relocate_comdat_behavior>
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255inline void
256relocate_section(
92e059d8 257 const Relocate_info<size, big_endian>* relinfo,
ead1e424 258 Target_type* target,
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259 const unsigned char* prelocs,
260 size_t reloc_count,
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261 Output_section* output_section,
262 bool needs_special_offset_handling,
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263 unsigned char* view,
264 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
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265 section_size_type view_size,
266 const Reloc_symbol_changes* reloc_symbol_changes)
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267{
268 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
269 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
270 Relocate relocate;
168a4726 271 Relocate_comdat_behavior relocate_comdat_behavior;
61ba1cf9 272
6fa2a40b 273 Sized_relobj_file<size, big_endian>* object = relinfo->object;
730cdc88 274 unsigned int local_count = object->local_symbol_count();
92e059d8 275
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276 Comdat_behavior comdat_behavior = CB_UNDETERMINED;
277
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278 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
279 {
280 Reltype reloc(prelocs);
281
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282 section_offset_type offset =
283 convert_to_section_size_type(reloc.get_r_offset());
61ba1cf9 284
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285 if (needs_special_offset_handling)
286 {
287 offset = output_section->output_offset(relinfo->object,
288 relinfo->data_shndx,
289 offset);
290 if (offset == -1)
291 continue;
292 }
293
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294 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
295 unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
296 unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
297
c06b7b0b 298 const Sized_symbol<size>* sym;
61ba1cf9 299
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300 Symbol_value<size> symval;
301 const Symbol_value<size> *psymval;
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302 bool is_defined_in_discarded_section;
303 unsigned int shndx;
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304 if (r_sym < local_count
305 && (reloc_symbol_changes == NULL
306 || (*reloc_symbol_changes)[i] == NULL))
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307 {
308 sym = NULL;
730cdc88 309 psymval = object->local_symbol(r_sym);
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310
311 // If the local symbol belongs to a section we are discarding,
312 // and that section is a debug section, try to find the
313 // corresponding kept section and map this symbol to its
ef15dade
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314 // counterpart in the kept section. The symbol must not
315 // correspond to a section we are folding.
e94cf127 316 bool is_ordinary;
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317 shndx = psymval->input_shndx(&is_ordinary);
318 is_defined_in_discarded_section =
319 (is_ordinary
320 && shndx != elfcpp::SHN_UNDEF
321 && !object->is_section_included(shndx)
322 && !relinfo->symtab->is_section_folded(object, shndx));
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323 }
324 else
325 {
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326 const Symbol* gsym;
327 if (reloc_symbol_changes != NULL
328 && (*reloc_symbol_changes)[i] != NULL)
329 gsym = (*reloc_symbol_changes)[i];
330 else
331 {
332 gsym = object->global_symbol(r_sym);
333 gold_assert(gsym != NULL);
334 if (gsym->is_forwarder())
335 gsym = relinfo->symtab->resolve_forwards(gsym);
336 }
61ba1cf9 337
c06b7b0b 338 sym = static_cast<const Sized_symbol<size>*>(gsym);
d3bbad62 339 if (sym->has_symtab_index() && sym->symtab_index() != -1U)
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340 symval.set_output_symtab_index(sym->symtab_index());
341 else
342 symval.set_no_output_symtab_entry();
343 symval.set_output_value(sym->value());
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344 if (gsym->type() == elfcpp::STT_TLS)
345 symval.set_is_tls_symbol();
346 else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
347 symval.set_is_ifunc_symbol();
b8e6aad9 348 psymval = &symval;
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349
350 is_defined_in_discarded_section =
351 (gsym->is_defined_in_discarded_section()
352 && gsym->is_undefined());
353 shndx = 0;
354 }
355
356 Symbol_value<size> symval2;
357 if (is_defined_in_discarded_section)
358 {
359 if (comdat_behavior == CB_UNDETERMINED)
360 {
361 std::string name = object->section_name(relinfo->data_shndx);
168a4726 362 comdat_behavior = relocate_comdat_behavior.get(name.c_str());
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363 }
364 if (comdat_behavior == CB_PRETEND)
365 {
366 // FIXME: This case does not work for global symbols.
367 // We have no place to store the original section index.
368 // Fortunately this does not matter for comdat sections,
369 // only for sections explicitly discarded by a linker
370 // script.
371 bool found;
372 typename elfcpp::Elf_types<size>::Elf_Addr value =
373 object->map_to_kept_section(shndx, &found);
374 if (found)
375 symval2.set_output_value(value + psymval->input_value());
376 else
377 symval2.set_output_value(0);
378 }
379 else
380 {
381 if (comdat_behavior == CB_WARNING)
382 gold_warning_at_location(relinfo, i, offset,
383 _("relocation refers to discarded "
384 "section"));
385 symval2.set_output_value(0);
386 }
387 symval2.set_no_output_symtab_entry();
388 psymval = &symval2;
ead1e424 389 }
61ba1cf9 390
031cdbed
ILT
391 if (!relocate.relocate(relinfo, target, output_section, i, reloc,
392 r_type, sym, psymval, view + offset,
393 view_address + offset, view_size))
ead1e424
ILT
394 continue;
395
fe8718a4 396 if (offset < 0 || static_cast<section_size_type>(offset) >= view_size)
ead1e424 397 {
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ILT
398 gold_error_at_location(relinfo, i, offset,
399 _("reloc has bad offset %zu"),
400 static_cast<size_t>(offset));
401 continue;
61ba1cf9
ILT
402 }
403
191f1a2d 404 if (issue_undefined_symbol_error(sym))
f073bbf7 405 gold_undefined_symbol_at_location(sym, relinfo, i, offset);
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ILT
406 else if (sym != NULL
407 && sym->visibility() != elfcpp::STV_DEFAULT
408 && (sym->is_undefined() || sym->is_from_dynobj()))
409 visibility_error(sym);
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410
411 if (sym != NULL && sym->has_warning())
75f2446e 412 relinfo->symtab->issue_warning(sym, relinfo, i, offset);
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413 }
414}
415
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416// Apply an incremental relocation.
417
418template<int size, bool big_endian, typename Target_type,
419 typename Relocate>
420void
421apply_relocation(const Relocate_info<size, big_endian>* relinfo,
422 Target_type* target,
423 typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
424 unsigned int r_type,
425 typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
426 const Symbol* gsym,
427 unsigned char* view,
428 typename elfcpp::Elf_types<size>::Elf_Addr address,
429 section_size_type view_size)
430{
431 // Construct the ELF relocation in a temporary buffer.
d55525b9 432 const int reloc_size = elfcpp::Elf_sizes<size>::rela_size;
94a3fc8b 433 unsigned char relbuf[reloc_size];
d55525b9
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434 elfcpp::Rela<size, big_endian> rel(relbuf);
435 elfcpp::Rela_write<size, big_endian> orel(relbuf);
94a3fc8b 436 orel.put_r_offset(r_offset);
d55525b9 437 orel.put_r_info(elfcpp::elf_r_info<size>(0, r_type));
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438 orel.put_r_addend(r_addend);
439
440 // Setup a Symbol_value for the global symbol.
d55525b9
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441 const Sized_symbol<size>* sym = static_cast<const Sized_symbol<size>*>(gsym);
442 Symbol_value<size> symval;
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443 gold_assert(sym->has_symtab_index() && sym->symtab_index() != -1U);
444 symval.set_output_symtab_index(sym->symtab_index());
445 symval.set_output_value(sym->value());
446 if (gsym->type() == elfcpp::STT_TLS)
447 symval.set_is_tls_symbol();
448 else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
449 symval.set_is_ifunc_symbol();
450
451 Relocate relocate;
452 relocate.relocate(relinfo, target, NULL, -1U, rel, r_type, sym, &symval,
453 view + r_offset, address + r_offset, view_size);
454}
455
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456// This class may be used as a typical class for the
457// Scan_relocatable_reloc parameter to scan_relocatable_relocs. The
458// template parameter Classify_reloc must be a class type which
459// provides a function get_size_for_reloc which returns the number of
460// bytes to which a reloc applies. This class is intended to capture
461// the most typical target behaviour, while still permitting targets
462// to define their own independent class for Scan_relocatable_reloc.
463
464template<int sh_type, typename Classify_reloc>
465class Default_scan_relocatable_relocs
466{
467 public:
468 // Return the strategy to use for a local symbol which is not a
469 // section symbol, given the relocation type.
470 inline Relocatable_relocs::Reloc_strategy
68943102 471 local_non_section_strategy(unsigned int r_type, Relobj*, unsigned int r_sym)
c2508178
ILT
472 {
473 // We assume that relocation type 0 is NONE. Targets which are
474 // different must override.
68943102 475 if (r_type == 0 && r_sym == 0)
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476 return Relocatable_relocs::RELOC_DISCARD;
477 return Relocatable_relocs::RELOC_COPY;
478 }
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479
480 // Return the strategy to use for a local symbol which is a section
481 // symbol, given the relocation type.
482 inline Relocatable_relocs::Reloc_strategy
483 local_section_strategy(unsigned int r_type, Relobj* object)
484 {
485 if (sh_type == elfcpp::SHT_RELA)
486 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
487 else
488 {
489 Classify_reloc classify;
490 switch (classify.get_size_for_reloc(r_type, object))
491 {
492 case 0:
7019cd25 493 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
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494 case 1:
495 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1;
496 case 2:
497 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2;
498 case 4:
499 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4;
500 case 8:
501 return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8;
502 default:
503 gold_unreachable();
504 }
505 }
506 }
507
508 // Return the strategy to use for a global symbol, given the
509 // relocation type, the object, and the symbol index.
510 inline Relocatable_relocs::Reloc_strategy
68943102
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511 global_strategy(unsigned int, Relobj*, unsigned int)
512 { return Relocatable_relocs::RELOC_COPY; }
6a74a719
ILT
513};
514
515// Scan relocs during a relocatable link. This is a default
516// definition which should work for most targets.
517// Scan_relocatable_reloc must name a class type which provides three
518// functions which return a Relocatable_relocs::Reloc_strategy code:
519// global_strategy, local_non_section_strategy, and
520// local_section_strategy. Most targets should be able to use
521// Default_scan_relocatable_relocs as this class.
522
7019cd25 523template<int size, bool big_endian, int sh_type,
6a74a719
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524 typename Scan_relocatable_reloc>
525void
526scan_relocatable_relocs(
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527 Symbol_table*,
528 Layout*,
6fa2a40b 529 Sized_relobj_file<size, big_endian>* object,
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530 unsigned int data_shndx,
531 const unsigned char* prelocs,
532 size_t reloc_count,
533 Output_section* output_section,
534 bool needs_special_offset_handling,
535 size_t local_symbol_count,
536 const unsigned char* plocal_syms,
537 Relocatable_relocs* rr)
538{
539 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
540 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
541 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
542 Scan_relocatable_reloc scan;
543
544 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
545 {
546 Reltype reloc(prelocs);
547
548 Relocatable_relocs::Reloc_strategy strategy;
549
550 if (needs_special_offset_handling
551 && !output_section->is_input_address_mapped(object, data_shndx,
552 reloc.get_r_offset()))
553 strategy = Relocatable_relocs::RELOC_DISCARD;
554 else
555 {
556 typename elfcpp::Elf_types<size>::Elf_WXword r_info =
557 reloc.get_r_info();
558 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
559 const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
560
561 if (r_sym >= local_symbol_count)
562 strategy = scan.global_strategy(r_type, object, r_sym);
563 else
564 {
565 gold_assert(plocal_syms != NULL);
566 typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
567 + r_sym * sym_size);
d491d34e
ILT
568 unsigned int shndx = lsym.get_st_shndx();
569 bool is_ordinary;
570 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
571 if (is_ordinary
6a74a719 572 && shndx != elfcpp::SHN_UNDEF
d491d34e 573 && !object->is_section_included(shndx))
6a74a719
ILT
574 {
575 // RELOC is a relocation against a local symbol
576 // defined in a section we are discarding. Discard
577 // the reloc. FIXME: Should we issue a warning?
578 strategy = Relocatable_relocs::RELOC_DISCARD;
579 }
580 else if (lsym.get_st_type() != elfcpp::STT_SECTION)
68943102
ILT
581 strategy = scan.local_non_section_strategy(r_type, object,
582 r_sym);
6a74a719
ILT
583 else
584 {
585 strategy = scan.local_section_strategy(r_type, object);
586 if (strategy != Relocatable_relocs::RELOC_DISCARD)
ef9beddf 587 object->output_section(shndx)->set_needs_symtab_index();
6a74a719 588 }
d3bbad62
ILT
589
590 if (strategy == Relocatable_relocs::RELOC_COPY)
591 object->set_must_have_output_symtab_entry(r_sym);
6a74a719
ILT
592 }
593 }
594
595 rr->set_next_reloc_strategy(strategy);
596 }
597}
598
7404fe1b
AM
599// Relocate relocs. Called for a relocatable link, and for --emit-relocs.
600// This is a default definition which should work for most targets.
6a74a719 601
7019cd25 602template<int size, bool big_endian, int sh_type>
6a74a719 603void
7404fe1b 604relocate_relocs(
6a74a719
ILT
605 const Relocate_info<size, big_endian>* relinfo,
606 const unsigned char* prelocs,
607 size_t reloc_count,
608 Output_section* output_section,
ef9beddf 609 typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section,
6a74a719
ILT
610 const Relocatable_relocs* rr,
611 unsigned char* view,
6be6f3bd 612 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
5c388529 613 section_size_type view_size,
6a74a719
ILT
614 unsigned char* reloc_view,
615 section_size_type reloc_view_size)
616{
ef9beddf 617 typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
6a74a719
ILT
618 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
619 typedef typename Reloc_types<sh_type, size, big_endian>::Reloc_write
620 Reltype_write;
621 const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
eff45813 622 const Address invalid_address = static_cast<Address>(0) - 1;
6a74a719 623
6fa2a40b 624 Sized_relobj_file<size, big_endian>* const object = relinfo->object;
6a74a719
ILT
625 const unsigned int local_count = object->local_symbol_count();
626
627 unsigned char* pwrite = reloc_view;
628
629 for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
630 {
631 Relocatable_relocs::Reloc_strategy strategy = rr->strategy(i);
632 if (strategy == Relocatable_relocs::RELOC_DISCARD)
633 continue;
634
5c388529
DK
635 if (strategy == Relocatable_relocs::RELOC_SPECIAL)
636 {
637 // Target wants to handle this relocation.
638 Sized_target<size, big_endian>* target =
639 parameters->sized_target<size, big_endian>();
640 target->relocate_special_relocatable(relinfo, sh_type, prelocs,
641 i, output_section,
642 offset_in_output_section,
643 view, view_address,
644 view_size, pwrite);
645 pwrite += reloc_size;
646 continue;
647 }
6a74a719
ILT
648 Reltype reloc(prelocs);
649 Reltype_write reloc_write(pwrite);
650
651 typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
652 const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
653 const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
654
655 // Get the new symbol index.
656
657 unsigned int new_symndx;
658 if (r_sym < local_count)
659 {
660 switch (strategy)
661 {
662 case Relocatable_relocs::RELOC_COPY:
818bf354
ILT
663 if (r_sym == 0)
664 new_symndx = 0;
665 else
666 {
667 new_symndx = object->symtab_index(r_sym);
668 gold_assert(new_symndx != -1U);
669 }
6a74a719
ILT
670 break;
671
672 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
7019cd25 673 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
6a74a719
ILT
674 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
675 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
676 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
677 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
2c339f71 678 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4_UNALIGNED:
6a74a719
ILT
679 {
680 // We are adjusting a section symbol. We need to find
681 // the symbol table index of the section symbol for
682 // the output section corresponding to input section
683 // in which this symbol is defined.
684 gold_assert(r_sym < local_count);
d491d34e
ILT
685 bool is_ordinary;
686 unsigned int shndx =
687 object->local_symbol_input_shndx(r_sym, &is_ordinary);
688 gold_assert(is_ordinary);
ef9beddf 689 Output_section* os = object->output_section(shndx);
6a74a719
ILT
690 gold_assert(os != NULL);
691 gold_assert(os->needs_symtab_index());
692 new_symndx = os->symtab_index();
693 }
694 break;
695
696 default:
697 gold_unreachable();
698 }
699 }
700 else
701 {
702 const Symbol* gsym = object->global_symbol(r_sym);
703 gold_assert(gsym != NULL);
704 if (gsym->is_forwarder())
705 gsym = relinfo->symtab->resolve_forwards(gsym);
706
707 gold_assert(gsym->has_symtab_index());
708 new_symndx = gsym->symtab_index();
709 }
710
711 // Get the new offset--the location in the output section where
712 // this relocation should be applied.
713
ef9beddf
ILT
714 Address offset = reloc.get_r_offset();
715 Address new_offset;
eff45813 716 if (offset_in_output_section != invalid_address)
6a74a719
ILT
717 new_offset = offset + offset_in_output_section;
718 else
719 {
ef9beddf
ILT
720 section_offset_type sot_offset =
721 convert_types<section_offset_type, Address>(offset);
722 section_offset_type new_sot_offset =
723 output_section->output_offset(object, relinfo->data_shndx,
724 sot_offset);
725 gold_assert(new_sot_offset != -1);
726 new_offset = new_sot_offset;
6a74a719
ILT
727 }
728
6be6f3bd
ILT
729 // In an object file, r_offset is an offset within the section.
730 // In an executable or dynamic object, generated by
731 // --emit-relocs, r_offset is an absolute address.
732 if (!parameters->options().relocatable())
e09ad04a
ILT
733 {
734 new_offset += view_address;
eff45813 735 if (offset_in_output_section != invalid_address)
e09ad04a
ILT
736 new_offset -= offset_in_output_section;
737 }
6be6f3bd 738
6a74a719
ILT
739 reloc_write.put_r_offset(new_offset);
740 reloc_write.put_r_info(elfcpp::elf_r_info<size>(new_symndx, r_type));
741
742 // Handle the reloc addend based on the strategy.
743
744 if (strategy == Relocatable_relocs::RELOC_COPY)
745 {
746 if (sh_type == elfcpp::SHT_RELA)
747 Reloc_types<sh_type, size, big_endian>::
748 copy_reloc_addend(&reloc_write,
749 &reloc);
750 }
751 else
752 {
753 // The relocation uses a section symbol in the input file.
754 // We are adjusting it to use a section symbol in the output
755 // file. The input section symbol refers to some address in
756 // the input section. We need the relocation in the output
757 // file to refer to that same address. This adjustment to
758 // the addend is the same calculation we use for a simple
759 // absolute relocation for the input section symbol.
760
761 const Symbol_value<size>* psymval = object->local_symbol(r_sym);
762
763 unsigned char* padd = view + offset;
764 switch (strategy)
765 {
766 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
767 {
768 typename elfcpp::Elf_types<size>::Elf_Swxword addend;
769 addend = Reloc_types<sh_type, size, big_endian>::
770 get_reloc_addend(&reloc);
771 addend = psymval->value(object, addend);
772 Reloc_types<sh_type, size, big_endian>::
773 set_reloc_addend(&reloc_write, addend);
774 }
775 break;
776
7019cd25
ILT
777 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
778 break;
779
6a74a719
ILT
780 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
781 Relocate_functions<size, big_endian>::rel8(padd, object,
782 psymval);
783 break;
784
785 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
786 Relocate_functions<size, big_endian>::rel16(padd, object,
787 psymval);
788 break;
789
790 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
791 Relocate_functions<size, big_endian>::rel32(padd, object,
792 psymval);
793 break;
794
795 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
796 Relocate_functions<size, big_endian>::rel64(padd, object,
797 psymval);
798 break;
799
2c339f71
DK
800 case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4_UNALIGNED:
801 Relocate_functions<size, big_endian>::rel32_unaligned(padd,
802 object,
803 psymval);
804 break;
805
6a74a719
ILT
806 default:
807 gold_unreachable();
808 }
809 }
810
811 pwrite += reloc_size;
812 }
813
814 gold_assert(static_cast<section_size_type>(pwrite - reloc_view)
815 == reloc_view_size);
816}
817
61ba1cf9
ILT
818} // End namespace gold.
819
820#endif // !defined(GOLD_TARGET_RELOC_H)
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