bfd/
[deliverable/binutils-gdb.git] / gold / i386.cc
CommitLineData
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1// i386.cc -- i386 target support for gold.
2
ebdbb458 3// Copyright 2006, 2007, 2008 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
14bfc3f5 23#include "gold.h"
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24
25#include <cstring>
26
14bfc3f5 27#include "elfcpp.h"
7e1edb90 28#include "parameters.h"
92e059d8 29#include "reloc.h"
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30#include "i386.h"
31#include "object.h"
ead1e424 32#include "symtab.h"
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33#include "layout.h"
34#include "output.h"
12c0daef 35#include "copy-relocs.h"
14bfc3f5 36#include "target.h"
61ba1cf9 37#include "target-reloc.h"
14bfc3f5 38#include "target-select.h"
af6359d5 39#include "tls.h"
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40
41namespace
42{
43
44using namespace gold;
45
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46class Output_data_plt_i386;
47
14bfc3f5 48// The i386 target class.
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49// TLS info comes from
50// http://people.redhat.com/drepper/tls.pdf
51// http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
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52
53class Target_i386 : public Sized_target<32, false>
54{
55 public:
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56 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
57
14bfc3f5 58 Target_i386()
ead1e424 59 : Sized_target<32, false>(&i386_info),
5a6f7e2d 60 got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
12c0daef 61 copy_relocs_(elfcpp::R_386_COPY), dynbss_(NULL),
edfbb029 62 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
14bfc3f5 63 { }
75f65a3e 64
92e059d8 65 // Scan the relocations to look for symbol adjustments.
61ba1cf9 66 void
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67 scan_relocs(const General_options& options,
68 Symbol_table* symtab,
ead1e424 69 Layout* layout,
f6ce93d6 70 Sized_relobj<32, false>* object,
a3ad94ed 71 unsigned int data_shndx,
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72 unsigned int sh_type,
73 const unsigned char* prelocs,
74 size_t reloc_count,
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75 Output_section* output_section,
76 bool needs_special_offset_handling,
92e059d8 77 size_t local_symbol_count,
730cdc88 78 const unsigned char* plocal_symbols);
61ba1cf9 79
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80 // Finalize the sections.
81 void
7e1edb90 82 do_finalize_sections(Layout*);
5a6f7e2d 83
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84 // Return the value to use for a dynamic which requires special
85 // treatment.
86 uint64_t
87 do_dynsym_value(const Symbol*) const;
88
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89 // Relocate a section.
90 void
91 relocate_section(const Relocate_info<32, false>*,
92 unsigned int sh_type,
93 const unsigned char* prelocs,
94 size_t reloc_count,
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95 Output_section* output_section,
96 bool needs_special_offset_handling,
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97 unsigned char* view,
98 elfcpp::Elf_types<32>::Elf_Addr view_address,
fe8718a4 99 section_size_type view_size);
92e059d8 100
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101 // Scan the relocs during a relocatable link.
102 void
103 scan_relocatable_relocs(const General_options& options,
104 Symbol_table* symtab,
105 Layout* layout,
106 Sized_relobj<32, false>* object,
107 unsigned int data_shndx,
108 unsigned int sh_type,
109 const unsigned char* prelocs,
110 size_t reloc_count,
111 Output_section* output_section,
112 bool needs_special_offset_handling,
113 size_t local_symbol_count,
114 const unsigned char* plocal_symbols,
115 Relocatable_relocs*);
116
117 // Relocate a section during a relocatable link.
118 void
119 relocate_for_relocatable(const Relocate_info<32, false>*,
120 unsigned int sh_type,
121 const unsigned char* prelocs,
122 size_t reloc_count,
123 Output_section* output_section,
124 off_t offset_in_output_section,
125 const Relocatable_relocs*,
126 unsigned char* view,
127 elfcpp::Elf_types<32>::Elf_Addr view_address,
128 section_size_type view_size,
129 unsigned char* reloc_view,
130 section_size_type reloc_view_size);
131
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132 // Return a string used to fill a code section with nops.
133 std::string
8851ecca 134 do_code_fill(section_size_type length) const;
c51e6221 135
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136 // Return whether SYM is defined by the ABI.
137 bool
138 do_is_defined_by_abi(Symbol* sym) const
139 { return strcmp(sym->name(), "___tls_get_addr") == 0; }
140
96f2030e 141 // Return the size of the GOT section.
fe8718a4 142 section_size_type
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143 got_size()
144 {
145 gold_assert(this->got_ != NULL);
146 return this->got_->data_size();
147 }
148
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149 private:
150 // The class which scans relocations.
151 struct Scan
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152 {
153 inline void
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154 local(const General_options& options, Symbol_table* symtab,
155 Layout* layout, Target_i386* target,
f6ce93d6 156 Sized_relobj<32, false>* object,
a3ad94ed 157 unsigned int data_shndx,
07f397ab 158 Output_section* output_section,
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159 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
160 const elfcpp::Sym<32, false>& lsym);
61ba1cf9 161
92e059d8 162 inline void
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163 global(const General_options& options, Symbol_table* symtab,
164 Layout* layout, Target_i386* target,
f6ce93d6 165 Sized_relobj<32, false>* object,
a3ad94ed 166 unsigned int data_shndx,
07f397ab 167 Output_section* output_section,
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168 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
169 Symbol* gsym);
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170
171 static void
172 unsupported_reloc_local(Sized_relobj<32, false>*, unsigned int r_type);
173
174 static void
175 unsupported_reloc_global(Sized_relobj<32, false>*, unsigned int r_type,
176 Symbol*);
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177 };
178
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179 // The class which implements relocation.
180 class Relocate
181 {
182 public:
ead1e424 183 Relocate()
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184 : skip_call_tls_get_addr_(false),
185 local_dynamic_type_(LOCAL_DYNAMIC_NONE)
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186 { }
187
188 ~Relocate()
189 {
190 if (this->skip_call_tls_get_addr_)
191 {
192 // FIXME: This needs to specify the location somehow.
75f2446e 193 gold_error(_("missing expected TLS relocation"));
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194 }
195 }
196
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197 // Return whether the static relocation needs to be applied.
198 inline bool
199 should_apply_static_reloc(const Sized_symbol<32>* gsym,
0700cf32 200 int ref_flags,
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201 bool is_32bit);
202
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203 // Do a relocation. Return false if the caller should not issue
204 // any warnings about this relocation.
205 inline bool
206 relocate(const Relocate_info<32, false>*, Target_i386*, size_t relnum,
92e059d8 207 const elfcpp::Rel<32, false>&,
c06b7b0b 208 unsigned int r_type, const Sized_symbol<32>*,
b8e6aad9 209 const Symbol_value<32>*,
92e059d8 210 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
fe8718a4 211 section_size_type);
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212
213 private:
214 // Do a TLS relocation.
ead1e424 215 inline void
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216 relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
217 size_t relnum, const elfcpp::Rel<32, false>&,
c06b7b0b 218 unsigned int r_type, const Sized_symbol<32>*,
b8e6aad9 219 const Symbol_value<32>*,
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220 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
221 section_size_type);
92e059d8 222
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223 // Do a TLS General-Dynamic to Initial-Exec transition.
224 inline void
225 tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
226 Output_segment* tls_segment,
227 const elfcpp::Rel<32, false>&, unsigned int r_type,
228 elfcpp::Elf_types<32>::Elf_Addr value,
229 unsigned char* view,
fe8718a4 230 section_size_type view_size);
07f397ab 231
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232 // Do a TLS General-Dynamic to Local-Exec transition.
233 inline void
234 tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
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235 Output_segment* tls_segment,
236 const elfcpp::Rel<32, false>&, unsigned int r_type,
237 elfcpp::Elf_types<32>::Elf_Addr value,
238 unsigned char* view,
fe8718a4 239 section_size_type view_size);
92e059d8 240
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241 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
242 // transition.
243 inline void
244 tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
245 Output_segment* tls_segment,
246 const elfcpp::Rel<32, false>&, unsigned int r_type,
247 elfcpp::Elf_types<32>::Elf_Addr value,
248 unsigned char* view,
249 section_size_type view_size);
250
251 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
252 // transition.
253 inline void
254 tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
255 Output_segment* tls_segment,
256 const elfcpp::Rel<32, false>&, unsigned int r_type,
257 elfcpp::Elf_types<32>::Elf_Addr value,
258 unsigned char* view,
259 section_size_type view_size);
260
56622147 261 // Do a TLS Local-Dynamic to Local-Exec transition.
ead1e424 262 inline void
56622147 263 tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
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264 Output_segment* tls_segment,
265 const elfcpp::Rel<32, false>&, unsigned int r_type,
266 elfcpp::Elf_types<32>::Elf_Addr value,
267 unsigned char* view,
fe8718a4 268 section_size_type view_size);
ead1e424 269
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270 // Do a TLS Initial-Exec to Local-Exec transition.
271 static inline void
272 tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
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273 Output_segment* tls_segment,
274 const elfcpp::Rel<32, false>&, unsigned int r_type,
275 elfcpp::Elf_types<32>::Elf_Addr value,
276 unsigned char* view,
fe8718a4 277 section_size_type view_size);
46cf9fa2 278
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279 // We need to keep track of which type of local dynamic relocation
280 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
281 enum Local_dynamic_type
282 {
283 LOCAL_DYNAMIC_NONE,
284 LOCAL_DYNAMIC_SUN,
285 LOCAL_DYNAMIC_GNU
286 };
287
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288 // This is set if we should skip the next reloc, which should be a
289 // PLT32 reloc against ___tls_get_addr.
290 bool skip_call_tls_get_addr_;
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291 // The type of local dynamic relocation we have seen in the section
292 // being relocated, if any.
293 Local_dynamic_type local_dynamic_type_;
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294 };
295
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296 // A class which returns the size required for a relocation type,
297 // used while scanning relocs during a relocatable link.
298 class Relocatable_size_for_reloc
299 {
300 public:
301 unsigned int
302 get_size_for_reloc(unsigned int, Relobj*);
303 };
304
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305 // Adjust TLS relocation type based on the options and whether this
306 // is a local symbol.
af6359d5 307 static tls::Tls_optimization
7e1edb90 308 optimize_tls_reloc(bool is_final, int r_type);
92e059d8 309
ead1e424 310 // Get the GOT section, creating it if necessary.
dbe717ef 311 Output_data_got<32, false>*
7e1edb90 312 got_section(Symbol_table*, Layout*);
a3ad94ed 313
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314 // Get the GOT PLT section.
315 Output_data_space*
316 got_plt_section() const
317 {
318 gold_assert(this->got_plt_ != NULL);
319 return this->got_plt_;
320 }
321
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322 // Create a PLT entry for a global symbol.
323 void
7e1edb90 324 make_plt_entry(Symbol_table*, Layout*, Symbol*);
a3ad94ed 325
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326 // Define the _TLS_MODULE_BASE_ symbol at the end of the TLS segment.
327 void
328 define_tls_base_symbol(Symbol_table*, Layout*);
329
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330 // Create a GOT entry for the TLS module index.
331 unsigned int
332 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
333 Sized_relobj<32, false>* object);
334
a3ad94ed 335 // Get the PLT section.
7bb3655e 336 const Output_data_plt_i386*
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337 plt_section() const
338 {
339 gold_assert(this->plt_ != NULL);
340 return this->plt_;
341 }
342
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343 // Get the dynamic reloc section, creating it if necessary.
344 Reloc_section*
345 rel_dyn_section(Layout*);
346
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347 // Return true if the symbol may need a COPY relocation.
348 // References from an executable object to non-function symbols
349 // defined in a dynamic object may need a COPY relocation.
350 bool
351 may_need_copy_reloc(Symbol* gsym)
352 {
8851ecca 353 return (!parameters->options().shared()
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354 && gsym->is_from_dynobj()
355 && gsym->type() != elfcpp::STT_FUNC);
356 }
357
12c0daef 358 // Add a potential copy relocation.
a3ad94ed 359 void
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360 copy_reloc(Symbol_table* symtab, Layout* layout, Relobj* object,
361 unsigned int shndx, Output_section* output_section,
362 Symbol* sym, const elfcpp::Rel<32, false>& reloc)
363 {
364 this->copy_relocs_.copy_reloc(symtab, layout,
365 symtab->get_sized_symbol<32>(sym),
366 object, shndx, output_section, reloc,
367 this->rel_dyn_section(layout));
368 }
ead1e424 369
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370 // Information about this specific target which we pass to the
371 // general Target structure.
75f65a3e 372 static const Target::Target_info i386_info;
ead1e424 373
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374 // The types of GOT entries needed for this platform.
375 enum Got_type
376 {
377 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
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378 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
379 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
380 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
381 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
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382 };
383
ead1e424 384 // The GOT section.
dbe717ef 385 Output_data_got<32, false>* got_;
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386 // The PLT section.
387 Output_data_plt_i386* plt_;
388 // The GOT PLT section.
389 Output_data_space* got_plt_;
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390 // The dynamic reloc section.
391 Reloc_section* rel_dyn_;
392 // Relocs saved to avoid a COPY reloc.
12c0daef 393 Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
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394 // Space for variables copied with a COPY reloc.
395 Output_data_space* dynbss_;
c2b45e22 396 // Offset of the GOT entry for the TLS module index.
94c4710f 397 unsigned int got_mod_index_offset_;
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398 // True if the _TLS_MODULE_BASE_ symbol has been defined.
399 bool tls_base_symbol_defined_;
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400};
401
402const Target::Target_info Target_i386::i386_info =
403{
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404 32, // size
405 false, // is_big_endian
406 elfcpp::EM_386, // machine_code
407 false, // has_make_symbol
dbe717ef 408 false, // has_resolve
c51e6221 409 true, // has_code_fill
35cdfc9a 410 true, // is_default_stack_executable
0864d551 411 '\0', // wrap_char
dbe717ef 412 "/usr/lib/libc.so.1", // dynamic_linker
0c5e9c22 413 0x08048000, // default_text_segment_address
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414 0x1000, // abi_pagesize (overridable by -z max-page-size)
415 0x1000 // common_pagesize (overridable by -z common-page-size)
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416};
417
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418// Get the GOT section, creating it if necessary.
419
dbe717ef 420Output_data_got<32, false>*
7e1edb90 421Target_i386::got_section(Symbol_table* symtab, Layout* layout)
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422{
423 if (this->got_ == NULL)
424 {
7e1edb90 425 gold_assert(symtab != NULL && layout != NULL);
a3ad94ed 426
7e1edb90 427 this->got_ = new Output_data_got<32, false>();
ead1e424 428
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429 Output_section* os;
430 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
431 (elfcpp::SHF_ALLOC
432 | elfcpp::SHF_WRITE),
433 this->got_);
434 os->set_is_relro();
ead1e424 435
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436 // The old GNU linker creates a .got.plt section. We just
437 // create another set of data in the .got section. Note that we
438 // always create a PLT if we create a GOT, although the PLT
439 // might be empty.
7d9e3d98 440 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
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441 os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
442 (elfcpp::SHF_ALLOC
443 | elfcpp::SHF_WRITE),
444 this->got_plt_);
445 os->set_is_relro();
a3ad94ed 446
ead1e424 447 // The first three entries are reserved.
27bc2bce 448 this->got_plt_->set_current_data_size(3 * 4);
ead1e424 449
a3ad94ed 450 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
9b07f471 451 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
a3ad94ed 452 this->got_plt_,
ead1e424 453 0, 0, elfcpp::STT_OBJECT,
16649710 454 elfcpp::STB_LOCAL,
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455 elfcpp::STV_HIDDEN, 0,
456 false, false);
457 }
a3ad94ed 458
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459 return this->got_;
460}
461
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462// Get the dynamic reloc section, creating it if necessary.
463
464Target_i386::Reloc_section*
465Target_i386::rel_dyn_section(Layout* layout)
466{
467 if (this->rel_dyn_ == NULL)
468 {
469 gold_assert(layout != NULL);
d98bc257 470 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
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471 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
472 elfcpp::SHF_ALLOC, this->rel_dyn_);
473 }
474 return this->rel_dyn_;
475}
476
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477// A class to handle the PLT data.
478
479class Output_data_plt_i386 : public Output_section_data
480{
481 public:
482 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
483
7e1edb90 484 Output_data_plt_i386(Layout*, Output_data_space*);
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485
486 // Add an entry to the PLT.
487 void
488 add_entry(Symbol* gsym);
489
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490 // Return the .rel.plt section data.
491 const Reloc_section*
492 rel_plt() const
493 { return this->rel_; }
494
495 protected:
496 void
497 do_adjust_output_section(Output_section* os);
498
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499 // Write to a map file.
500 void
501 do_print_to_mapfile(Mapfile* mapfile) const
502 { mapfile->print_output_data(this, _("** PLT")); }
503
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504 private:
505 // The size of an entry in the PLT.
506 static const int plt_entry_size = 16;
507
508 // The first entry in the PLT for an executable.
509 static unsigned char exec_first_plt_entry[plt_entry_size];
510
511 // The first entry in the PLT for a shared object.
512 static unsigned char dyn_first_plt_entry[plt_entry_size];
513
514 // Other entries in the PLT for an executable.
515 static unsigned char exec_plt_entry[plt_entry_size];
516
517 // Other entries in the PLT for a shared object.
518 static unsigned char dyn_plt_entry[plt_entry_size];
519
520 // Set the final size.
521 void
27bc2bce 522 set_final_data_size()
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523 { this->set_data_size((this->count_ + 1) * plt_entry_size); }
524
525 // Write out the PLT data.
526 void
527 do_write(Output_file*);
528
529 // The reloc section.
530 Reloc_section* rel_;
531 // The .got.plt section.
532 Output_data_space* got_plt_;
533 // The number of PLT entries.
534 unsigned int count_;
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535};
536
537// Create the PLT section. The ordinary .got section is an argument,
538// since we need to refer to the start. We also create our own .got
539// section just for PLT entries.
540
541Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
7e1edb90 542 Output_data_space* got_plt)
80576242 543 : Output_section_data(4), got_plt_(got_plt), count_(0)
a3ad94ed 544{
d98bc257 545 this->rel_ = new Reloc_section(false);
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546 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
547 elfcpp::SHF_ALLOC, this->rel_);
548}
549
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550void
551Output_data_plt_i386::do_adjust_output_section(Output_section* os)
552{
553 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
554 // linker, and so do we.
555 os->set_entsize(4);
556}
557
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558// Add an entry to the PLT.
559
560void
561Output_data_plt_i386::add_entry(Symbol* gsym)
562{
563 gold_assert(!gsym->has_plt_offset());
564
565 // Note that when setting the PLT offset we skip the initial
566 // reserved PLT entry.
567 gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
568
569 ++this->count_;
570
fe8718a4 571 section_offset_type got_offset = this->got_plt_->current_data_size();
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ILT
572
573 // Every PLT entry needs a GOT entry which points back to the PLT
574 // entry (this will be changed by the dynamic linker, normally
575 // lazily when the function is called).
27bc2bce 576 this->got_plt_->set_current_data_size(got_offset + 4);
a3ad94ed
ILT
577
578 // Every PLT entry needs a reloc.
16649710 579 gsym->set_needs_dynsym_entry();
a3ad94ed
ILT
580 this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
581 got_offset);
582
583 // Note that we don't need to save the symbol. The contents of the
584 // PLT are independent of which symbols are used. The symbols only
585 // appear in the relocations.
586}
587
588// The first entry in the PLT for an executable.
589
590unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] =
591{
592 0xff, 0x35, // pushl contents of memory address
593 0, 0, 0, 0, // replaced with address of .got + 4
594 0xff, 0x25, // jmp indirect
595 0, 0, 0, 0, // replaced with address of .got + 8
596 0, 0, 0, 0 // unused
597};
598
599// The first entry in the PLT for a shared object.
600
601unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] =
602{
603 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
604 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
605 0, 0, 0, 0 // unused
606};
607
608// Subsequent entries in the PLT for an executable.
609
610unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] =
611{
612 0xff, 0x25, // jmp indirect
613 0, 0, 0, 0, // replaced with address of symbol in .got
614 0x68, // pushl immediate
615 0, 0, 0, 0, // replaced with offset into relocation table
616 0xe9, // jmp relative
617 0, 0, 0, 0 // replaced with offset to start of .plt
618};
619
620// Subsequent entries in the PLT for a shared object.
621
622unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] =
623{
624 0xff, 0xa3, // jmp *offset(%ebx)
625 0, 0, 0, 0, // replaced with offset of symbol in .got
626 0x68, // pushl immediate
627 0, 0, 0, 0, // replaced with offset into relocation table
628 0xe9, // jmp relative
629 0, 0, 0, 0 // replaced with offset to start of .plt
630};
631
632// Write out the PLT. This uses the hand-coded instructions above,
633// and adjusts them as needed. This is all specified by the i386 ELF
634// Processor Supplement.
635
636void
637Output_data_plt_i386::do_write(Output_file* of)
638{
639 const off_t offset = this->offset();
fe8718a4
ILT
640 const section_size_type oview_size =
641 convert_to_section_size_type(this->data_size());
a3ad94ed
ILT
642 unsigned char* const oview = of->get_output_view(offset, oview_size);
643
644 const off_t got_file_offset = this->got_plt_->offset();
fe8718a4
ILT
645 const section_size_type got_size =
646 convert_to_section_size_type(this->got_plt_->data_size());
a3ad94ed
ILT
647 unsigned char* const got_view = of->get_output_view(got_file_offset,
648 got_size);
649
650 unsigned char* pov = oview;
651
652 elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
653 elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
654
8851ecca 655 if (parameters->options().shared())
a3ad94ed
ILT
656 memcpy(pov, dyn_first_plt_entry, plt_entry_size);
657 else
658 {
659 memcpy(pov, exec_first_plt_entry, plt_entry_size);
660 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
661 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
662 }
663 pov += plt_entry_size;
664
665 unsigned char* got_pov = got_view;
666
667 memset(got_pov, 0, 12);
668 got_pov += 12;
669
670 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
671
672 unsigned int plt_offset = plt_entry_size;
673 unsigned int plt_rel_offset = 0;
674 unsigned int got_offset = 12;
675 const unsigned int count = this->count_;
676 for (unsigned int i = 0;
677 i < count;
678 ++i,
679 pov += plt_entry_size,
680 got_pov += 4,
681 plt_offset += plt_entry_size,
682 plt_rel_offset += rel_size,
683 got_offset += 4)
684 {
685 // Set and adjust the PLT entry itself.
686
8851ecca 687 if (parameters->options().shared())
a3ad94ed
ILT
688 {
689 memcpy(pov, dyn_plt_entry, plt_entry_size);
690 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
691 }
692 else
693 {
694 memcpy(pov, exec_plt_entry, plt_entry_size);
695 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
696 (got_address
697 + got_offset));
698 }
699
700 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
701 elfcpp::Swap<32, false>::writeval(pov + 12,
702 - (plt_offset + plt_entry_size));
703
704 // Set the entry in the GOT.
705 elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6);
706 }
707
fe8718a4
ILT
708 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
709 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
a3ad94ed
ILT
710
711 of->write_output_view(offset, oview_size, oview);
712 of->write_output_view(got_file_offset, got_size, got_view);
713}
714
715// Create a PLT entry for a global symbol.
716
717void
7e1edb90 718Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
a3ad94ed
ILT
719{
720 if (gsym->has_plt_offset())
721 return;
722
723 if (this->plt_ == NULL)
724 {
725 // Create the GOT sections first.
7e1edb90 726 this->got_section(symtab, layout);
a3ad94ed 727
7e1edb90 728 this->plt_ = new Output_data_plt_i386(layout, this->got_plt_);
16649710
ILT
729 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
730 (elfcpp::SHF_ALLOC
731 | elfcpp::SHF_EXECINSTR),
732 this->plt_);
a3ad94ed
ILT
733 }
734
735 this->plt_->add_entry(gsym);
736}
737
edfbb029
CC
738// Define the _TLS_MODULE_BASE_ symbol at the end of the TLS segment.
739
740void
741Target_i386::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
742{
743 if (this->tls_base_symbol_defined_)
744 return;
745
746 Output_segment* tls_segment = layout->tls_segment();
747 if (tls_segment != NULL)
748 {
749 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
750 tls_segment, 0, 0,
751 elfcpp::STT_TLS,
752 elfcpp::STB_LOCAL,
753 elfcpp::STV_HIDDEN, 0,
754 Symbol::SEGMENT_END, true);
755 }
756 this->tls_base_symbol_defined_ = true;
757}
758
94c4710f
ILT
759// Create a GOT entry for the TLS module index.
760
761unsigned int
762Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
763 Sized_relobj<32, false>* object)
764{
765 if (this->got_mod_index_offset_ == -1U)
766 {
767 gold_assert(symtab != NULL && layout != NULL && object != NULL);
768 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
769 Output_data_got<32, false>* got = this->got_section(symtab, layout);
770 unsigned int got_offset = got->add_constant(0);
771 rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
772 got_offset);
009a67a2 773 got->add_constant(0);
94c4710f
ILT
774 this->got_mod_index_offset_ = got_offset;
775 }
776 return this->got_mod_index_offset_;
777}
778
92e059d8 779// Optimize the TLS relocation type based on what we know about the
a3ad94ed
ILT
780// symbol. IS_FINAL is true if the final address of this symbol is
781// known at link time.
92e059d8 782
af6359d5 783tls::Tls_optimization
7e1edb90 784Target_i386::optimize_tls_reloc(bool is_final, int r_type)
92e059d8
ILT
785{
786 // If we are generating a shared library, then we can't do anything
787 // in the linker.
8851ecca 788 if (parameters->options().shared())
af6359d5 789 return tls::TLSOPT_NONE;
92e059d8
ILT
790
791 switch (r_type)
792 {
793 case elfcpp::R_386_TLS_GD:
794 case elfcpp::R_386_TLS_GOTDESC:
795 case elfcpp::R_386_TLS_DESC_CALL:
e041f13d 796 // These are General-Dynamic which permits fully general TLS
92e059d8
ILT
797 // access. Since we know that we are generating an executable,
798 // we can convert this to Initial-Exec. If we also know that
799 // this is a local symbol, we can further switch to Local-Exec.
a3ad94ed 800 if (is_final)
af6359d5
ILT
801 return tls::TLSOPT_TO_LE;
802 return tls::TLSOPT_TO_IE;
92e059d8
ILT
803
804 case elfcpp::R_386_TLS_LDM:
805 // This is Local-Dynamic, which refers to a local symbol in the
806 // dynamic TLS block. Since we know that we generating an
807 // executable, we can switch to Local-Exec.
af6359d5 808 return tls::TLSOPT_TO_LE;
92e059d8
ILT
809
810 case elfcpp::R_386_TLS_LDO_32:
af6359d5
ILT
811 // Another type of Local-Dynamic relocation.
812 return tls::TLSOPT_TO_LE;
92e059d8
ILT
813
814 case elfcpp::R_386_TLS_IE:
815 case elfcpp::R_386_TLS_GOTIE:
816 case elfcpp::R_386_TLS_IE_32:
817 // These are Initial-Exec relocs which get the thread offset
818 // from the GOT. If we know that we are linking against the
819 // local symbol, we can switch to Local-Exec, which links the
820 // thread offset into the instruction.
a3ad94ed 821 if (is_final)
af6359d5
ILT
822 return tls::TLSOPT_TO_LE;
823 return tls::TLSOPT_NONE;
8462ae85 824
92e059d8
ILT
825 case elfcpp::R_386_TLS_LE:
826 case elfcpp::R_386_TLS_LE_32:
827 // When we already have Local-Exec, there is nothing further we
828 // can do.
af6359d5 829 return tls::TLSOPT_NONE;
92e059d8
ILT
830
831 default:
a3ad94ed 832 gold_unreachable();
92e059d8
ILT
833 }
834}
835
af6359d5
ILT
836// Report an unsupported relocation against a local symbol.
837
838void
839Target_i386::Scan::unsupported_reloc_local(Sized_relobj<32, false>* object,
840 unsigned int r_type)
841{
75f2446e
ILT
842 gold_error(_("%s: unsupported reloc %u against local symbol"),
843 object->name().c_str(), r_type);
af6359d5
ILT
844}
845
92e059d8
ILT
846// Scan a relocation for a local symbol.
847
848inline void
7e1edb90 849Target_i386::Scan::local(const General_options&,
ead1e424
ILT
850 Symbol_table* symtab,
851 Layout* layout,
852 Target_i386* target,
f6ce93d6 853 Sized_relobj<32, false>* object,
1b64748b 854 unsigned int data_shndx,
07f397ab 855 Output_section* output_section,
1b64748b 856 const elfcpp::Rel<32, false>& reloc,
a3ad94ed 857 unsigned int r_type,
7bf1f802 858 const elfcpp::Sym<32, false>& lsym)
92e059d8
ILT
859{
860 switch (r_type)
861 {
862 case elfcpp::R_386_NONE:
863 case elfcpp::R_386_GNU_VTINHERIT:
864 case elfcpp::R_386_GNU_VTENTRY:
865 break;
866
867 case elfcpp::R_386_32:
436ca963
ILT
868 // If building a shared library (or a position-independent
869 // executable), we need to create a dynamic relocation for
870 // this location. The relocation applied at link time will
871 // apply the link-time value, so we flag the location with
872 // an R_386_RELATIVE relocation so the dynamic loader can
873 // relocate it easily.
8851ecca 874 if (parameters->options().output_is_position_independent())
436ca963
ILT
875 {
876 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
e8c846c3
ILT
877 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
878 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
879 output_section, data_shndx,
880 reloc.get_r_offset());
d61c6bd4
ILT
881 }
882 break;
883
884 case elfcpp::R_386_16:
885 case elfcpp::R_386_8:
886 // If building a shared library (or a position-independent
887 // executable), we need to create a dynamic relocation for
888 // this location. Because the addend needs to remain in the
889 // data section, we need to be careful not to apply this
890 // relocation statically.
8851ecca 891 if (parameters->options().output_is_position_independent())
d61c6bd4
ILT
892 {
893 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
d491d34e 894 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
dceae3c1 895 if (lsym.get_st_type() != elfcpp::STT_SECTION)
d491d34e
ILT
896 rel_dyn->add_local(object, r_sym, r_type, output_section,
897 data_shndx, reloc.get_r_offset());
dceae3c1
ILT
898 else
899 {
900 gold_assert(lsym.get_st_value() == 0);
d491d34e
ILT
901 unsigned int shndx = lsym.get_st_shndx();
902 bool is_ordinary;
903 shndx = object->adjust_sym_shndx(r_sym, shndx,
904 &is_ordinary);
905 if (!is_ordinary)
906 object->error(_("section symbol %u has bad shndx %u"),
907 r_sym, shndx);
908 else
909 rel_dyn->add_local_section(object, shndx,
910 r_type, output_section,
911 data_shndx, reloc.get_r_offset());
dceae3c1 912 }
436ca963 913 }
92e059d8
ILT
914 break;
915
916 case elfcpp::R_386_PC32:
917 case elfcpp::R_386_PC16:
918 case elfcpp::R_386_PC8:
919 break;
920
df2efe71
ILT
921 case elfcpp::R_386_PLT32:
922 // Since we know this is a local symbol, we can handle this as a
923 // PC32 reloc.
924 break;
925
ead1e424
ILT
926 case elfcpp::R_386_GOTOFF:
927 case elfcpp::R_386_GOTPC:
928 // We need a GOT section.
7e1edb90 929 target->got_section(symtab, layout);
ead1e424
ILT
930 break;
931
1b64748b
ILT
932 case elfcpp::R_386_GOT32:
933 {
934 // The symbol requires a GOT entry.
935 Output_data_got<32, false>* got = target->got_section(symtab, layout);
936 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
0a65a3a7 937 if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
1b64748b
ILT
938 {
939 // If we are generating a shared object, we need to add a
7bf1f802 940 // dynamic RELATIVE relocation for this symbol's GOT entry.
8851ecca 941 if (parameters->options().output_is_position_independent())
1b64748b
ILT
942 {
943 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
e8c846c3 944 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
0a65a3a7
CC
945 rel_dyn->add_local_relative(
946 object, r_sym, elfcpp::R_386_RELATIVE, got,
947 object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
1b64748b
ILT
948 }
949 }
950 }
951 break;
952
af6359d5
ILT
953 // These are relocations which should only be seen by the
954 // dynamic linker, and should never be seen here.
92e059d8
ILT
955 case elfcpp::R_386_COPY:
956 case elfcpp::R_386_GLOB_DAT:
957 case elfcpp::R_386_JUMP_SLOT:
958 case elfcpp::R_386_RELATIVE:
959 case elfcpp::R_386_TLS_TPOFF:
960 case elfcpp::R_386_TLS_DTPMOD32:
961 case elfcpp::R_386_TLS_DTPOFF32:
962 case elfcpp::R_386_TLS_TPOFF32:
963 case elfcpp::R_386_TLS_DESC:
a0c4fb0a 964 gold_error(_("%s: unexpected reloc %u in object file"),
75f2446e 965 object->name().c_str(), r_type);
92e059d8
ILT
966 break;
967
af6359d5 968 // These are initial TLS relocs, which are expected when
d61c17ea 969 // linking.
56622147
ILT
970 case elfcpp::R_386_TLS_GD: // Global-dynamic
971 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
972 case elfcpp::R_386_TLS_DESC_CALL:
973 case elfcpp::R_386_TLS_LDM: // Local-dynamic
974 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
975 case elfcpp::R_386_TLS_IE: // Initial-exec
92e059d8 976 case elfcpp::R_386_TLS_IE_32:
56622147
ILT
977 case elfcpp::R_386_TLS_GOTIE:
978 case elfcpp::R_386_TLS_LE: // Local-exec
92e059d8 979 case elfcpp::R_386_TLS_LE_32:
7e1edb90 980 {
8851ecca 981 bool output_is_shared = parameters->options().shared();
af6359d5
ILT
982 const tls::Tls_optimization optimized_type
983 = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
7e1edb90
ILT
984 switch (r_type)
985 {
56622147 986 case elfcpp::R_386_TLS_GD: // Global-dynamic
07f397ab
ILT
987 if (optimized_type == tls::TLSOPT_NONE)
988 {
989 // Create a pair of GOT entries for the module index and
990 // dtv-relative offset.
991 Output_data_got<32, false>* got
992 = target->got_section(symtab, layout);
993 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
d491d34e
ILT
994 unsigned int shndx = lsym.get_st_shndx();
995 bool is_ordinary;
996 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
997 if (!is_ordinary)
998 object->error(_("local symbol %u has bad shndx %u"),
999 r_sym, shndx);
1000 else
1001 got->add_local_pair_with_rel(object, r_sym, shndx,
1002 GOT_TYPE_TLS_PAIR,
1003 target->rel_dyn_section(layout),
1004 elfcpp::R_386_TLS_DTPMOD32, 0);
07f397ab
ILT
1005 }
1006 else if (optimized_type != tls::TLSOPT_TO_LE)
1007 unsupported_reloc_local(object, r_type);
1008 break;
1009
56622147 1010 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva)
edfbb029 1011 target->define_tls_base_symbol(symtab, layout);
c2b45e22
CC
1012 if (optimized_type == tls::TLSOPT_NONE)
1013 {
1014 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1015 Output_data_got<32, false>* got
1016 = target->got_section(symtab, layout);
1017 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
d491d34e
ILT
1018 unsigned int shndx = lsym.get_st_shndx();
1019 bool is_ordinary;
1020 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1021 if (!is_ordinary)
1022 object->error(_("local symbol %u has bad shndx %u"),
1023 r_sym, shndx);
1024 else
1025 got->add_local_pair_with_rel(object, r_sym, shndx,
1026 GOT_TYPE_TLS_DESC,
1027 target->rel_dyn_section(layout),
1028 elfcpp::R_386_TLS_DESC, 0);
c2b45e22
CC
1029 }
1030 else if (optimized_type != tls::TLSOPT_TO_LE)
7bf1f802 1031 unsupported_reloc_local(object, r_type);
af6359d5
ILT
1032 break;
1033
c2b45e22
CC
1034 case elfcpp::R_386_TLS_DESC_CALL:
1035 break;
1036
56622147 1037 case elfcpp::R_386_TLS_LDM: // Local-dynamic
07f397ab
ILT
1038 if (optimized_type == tls::TLSOPT_NONE)
1039 {
1040 // Create a GOT entry for the module index.
94c4710f 1041 target->got_mod_index_entry(symtab, layout, object);
07f397ab
ILT
1042 }
1043 else if (optimized_type != tls::TLSOPT_TO_LE)
af6359d5
ILT
1044 unsupported_reloc_local(object, r_type);
1045 break;
1046
56622147 1047 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
46cf9fa2
ILT
1048 break;
1049
56622147
ILT
1050 case elfcpp::R_386_TLS_IE: // Initial-exec
1051 case elfcpp::R_386_TLS_IE_32:
1052 case elfcpp::R_386_TLS_GOTIE:
535890bb 1053 layout->set_has_static_tls();
07f397ab
ILT
1054 if (optimized_type == tls::TLSOPT_NONE)
1055 {
7bf1f802
ILT
1056 // For the R_386_TLS_IE relocation, we need to create a
1057 // dynamic relocation when building a shared library.
1058 if (r_type == elfcpp::R_386_TLS_IE
8851ecca 1059 && parameters->options().shared())
7bf1f802
ILT
1060 {
1061 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
e8c846c3
ILT
1062 unsigned int r_sym
1063 = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1064 rel_dyn->add_local_relative(object, r_sym,
1065 elfcpp::R_386_RELATIVE,
1066 output_section, data_shndx,
1067 reloc.get_r_offset());
7bf1f802 1068 }
07f397ab
ILT
1069 // Create a GOT entry for the tp-relative offset.
1070 Output_data_got<32, false>* got
1071 = target->got_section(symtab, layout);
1072 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
7bf1f802
ILT
1073 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1074 ? elfcpp::R_386_TLS_TPOFF32
1075 : elfcpp::R_386_TLS_TPOFF);
c2b45e22
CC
1076 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1077 ? GOT_TYPE_TLS_OFFSET
1078 : GOT_TYPE_TLS_NOFFSET);
1079 got->add_local_with_rel(object, r_sym, got_type,
7bf1f802
ILT
1080 target->rel_dyn_section(layout),
1081 dyn_r_type);
07f397ab
ILT
1082 }
1083 else if (optimized_type != tls::TLSOPT_TO_LE)
af6359d5 1084 unsupported_reloc_local(object, r_type);
7e1edb90 1085 break;
af6359d5 1086
56622147
ILT
1087 case elfcpp::R_386_TLS_LE: // Local-exec
1088 case elfcpp::R_386_TLS_LE_32:
535890bb 1089 layout->set_has_static_tls();
07f397ab 1090 if (output_is_shared)
7bf1f802
ILT
1091 {
1092 // We need to create a dynamic relocation.
dceae3c1 1093 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
7bf1f802
ILT
1094 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1095 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1096 ? elfcpp::R_386_TLS_TPOFF32
1097 : elfcpp::R_386_TLS_TPOFF);
1098 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1099 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
1100 data_shndx, reloc.get_r_offset());
1101 }
56622147
ILT
1102 break;
1103
af6359d5
ILT
1104 default:
1105 gold_unreachable();
7e1edb90
ILT
1106 }
1107 }
92e059d8
ILT
1108 break;
1109
92e059d8
ILT
1110 case elfcpp::R_386_32PLT:
1111 case elfcpp::R_386_TLS_GD_32:
1112 case elfcpp::R_386_TLS_GD_PUSH:
1113 case elfcpp::R_386_TLS_GD_CALL:
1114 case elfcpp::R_386_TLS_GD_POP:
1115 case elfcpp::R_386_TLS_LDM_32:
1116 case elfcpp::R_386_TLS_LDM_PUSH:
1117 case elfcpp::R_386_TLS_LDM_CALL:
1118 case elfcpp::R_386_TLS_LDM_POP:
1119 case elfcpp::R_386_USED_BY_INTEL_200:
1120 default:
af6359d5 1121 unsupported_reloc_local(object, r_type);
92e059d8
ILT
1122 break;
1123 }
1124}
1125
af6359d5
ILT
1126// Report an unsupported relocation against a global symbol.
1127
1128void
1129Target_i386::Scan::unsupported_reloc_global(Sized_relobj<32, false>* object,
1130 unsigned int r_type,
1131 Symbol* gsym)
1132{
75f2446e 1133 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
a2b1aa12 1134 object->name().c_str(), r_type, gsym->demangled_name().c_str());
af6359d5
ILT
1135}
1136
92e059d8
ILT
1137// Scan a relocation for a global symbol.
1138
1139inline void
12c0daef 1140Target_i386::Scan::global(const General_options&,
ead1e424
ILT
1141 Symbol_table* symtab,
1142 Layout* layout,
1143 Target_i386* target,
f6ce93d6 1144 Sized_relobj<32, false>* object,
a3ad94ed 1145 unsigned int data_shndx,
07f397ab 1146 Output_section* output_section,
a3ad94ed
ILT
1147 const elfcpp::Rel<32, false>& reloc,
1148 unsigned int r_type,
92e059d8
ILT
1149 Symbol* gsym)
1150{
1151 switch (r_type)
1152 {
1153 case elfcpp::R_386_NONE:
1154 case elfcpp::R_386_GNU_VTINHERIT:
8462ae85 1155 case elfcpp::R_386_GNU_VTENTRY:
92e059d8
ILT
1156 break;
1157
1158 case elfcpp::R_386_32:
92e059d8 1159 case elfcpp::R_386_16:
92e059d8 1160 case elfcpp::R_386_8:
96f2030e 1161 {
d61c6bd4
ILT
1162 // Make a PLT entry if necessary.
1163 if (gsym->needs_plt_entry())
1164 {
1165 target->make_plt_entry(symtab, layout, gsym);
1166 // Since this is not a PC-relative relocation, we may be
1167 // taking the address of a function. In that case we need to
1168 // set the entry in the dynamic symbol table to the address of
1169 // the PLT entry.
8851ecca 1170 if (gsym->is_from_dynobj() && !parameters->options().shared())
d61c6bd4
ILT
1171 gsym->set_needs_dynsym_value();
1172 }
1173 // Make a dynamic relocation if necessary.
0700cf32 1174 if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
d61c6bd4
ILT
1175 {
1176 if (target->may_need_copy_reloc(gsym))
1177 {
12c0daef 1178 target->copy_reloc(symtab, layout, object,
4f4c5f80 1179 data_shndx, output_section, gsym, reloc);
d61c6bd4
ILT
1180 }
1181 else if (r_type == elfcpp::R_386_32
1182 && gsym->can_use_relative_reloc(false))
1183 {
1184 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
e8c846c3
ILT
1185 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1186 output_section, object,
1187 data_shndx, reloc.get_r_offset());
d61c6bd4
ILT
1188 }
1189 else
1190 {
96f2030e 1191 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4f4c5f80
ILT
1192 rel_dyn->add_global(gsym, r_type, output_section, object,
1193 data_shndx, reloc.get_r_offset());
d61c6bd4
ILT
1194 }
1195 }
1196 }
1197 break;
1198
1199 case elfcpp::R_386_PC32:
1200 case elfcpp::R_386_PC16:
1201 case elfcpp::R_386_PC8:
1202 {
1203 // Make a PLT entry if necessary.
1204 if (gsym->needs_plt_entry())
7bf1f802
ILT
1205 {
1206 // These relocations are used for function calls only in
1207 // non-PIC code. For a 32-bit relocation in a shared library,
1208 // we'll need a text relocation anyway, so we can skip the
1209 // PLT entry and let the dynamic linker bind the call directly
1210 // to the target. For smaller relocations, we should use a
1211 // PLT entry to ensure that the call can reach.
8851ecca 1212 if (!parameters->options().shared()
7bf1f802
ILT
1213 || r_type != elfcpp::R_386_PC32)
1214 target->make_plt_entry(symtab, layout, gsym);
1215 }
d61c6bd4 1216 // Make a dynamic relocation if necessary.
0700cf32
ILT
1217 int flags = Symbol::NON_PIC_REF;
1218 if (gsym->type() == elfcpp::STT_FUNC)
1219 flags |= Symbol::FUNCTION_CALL;
1220 if (gsym->needs_dynamic_reloc(flags))
96f2030e 1221 {
d61c6bd4
ILT
1222 if (target->may_need_copy_reloc(gsym))
1223 {
12c0daef 1224 target->copy_reloc(symtab, layout, object,
4f4c5f80 1225 data_shndx, output_section, gsym, reloc);
d61c6bd4 1226 }
86849f1f 1227 else
d61c6bd4
ILT
1228 {
1229 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
4f4c5f80
ILT
1230 rel_dyn->add_global(gsym, r_type, output_section, object,
1231 data_shndx, reloc.get_r_offset());
d61c6bd4 1232 }
96f2030e
ILT
1233 }
1234 }
92e059d8
ILT
1235 break;
1236
ead1e424 1237 case elfcpp::R_386_GOT32:
8462ae85
ILT
1238 {
1239 // The symbol requires a GOT entry.
7e1edb90 1240 Output_data_got<32, false>* got = target->got_section(symtab, layout);
7bf1f802 1241 if (gsym->final_value_is_known())
0a65a3a7 1242 got->add_global(gsym, GOT_TYPE_STANDARD);
7bf1f802
ILT
1243 else
1244 {
8462ae85 1245 // If this symbol is not fully resolved, we need to add a
7bf1f802
ILT
1246 // GOT entry with a dynamic relocation.
1247 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
8fc19601
ILT
1248 if (gsym->is_from_dynobj()
1249 || gsym->is_undefined()
1250 || gsym->is_preemptible())
0a65a3a7
CC
1251 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
1252 rel_dyn, elfcpp::R_386_GLOB_DAT);
7bf1f802 1253 else
8462ae85 1254 {
0a65a3a7
CC
1255 if (got->add_global(gsym, GOT_TYPE_STANDARD))
1256 rel_dyn->add_global_relative(
1257 gsym, elfcpp::R_386_RELATIVE, got,
1258 gsym->got_offset(GOT_TYPE_STANDARD));
8462ae85
ILT
1259 }
1260 }
1261 }
ead1e424
ILT
1262 break;
1263
1264 case elfcpp::R_386_PLT32:
a3ad94ed
ILT
1265 // If the symbol is fully resolved, this is just a PC32 reloc.
1266 // Otherwise we need a PLT entry.
7e1edb90 1267 if (gsym->final_value_is_known())
ead1e424 1268 break;
436ca963
ILT
1269 // If building a shared library, we can also skip the PLT entry
1270 // if the symbol is defined in the output file and is protected
1271 // or hidden.
1272 if (gsym->is_defined()
1273 && !gsym->is_from_dynobj()
1274 && !gsym->is_preemptible())
1275 break;
7e1edb90 1276 target->make_plt_entry(symtab, layout, gsym);
ead1e424
ILT
1277 break;
1278
1279 case elfcpp::R_386_GOTOFF:
1280 case elfcpp::R_386_GOTPC:
1281 // We need a GOT section.
7e1edb90 1282 target->got_section(symtab, layout);
ead1e424
ILT
1283 break;
1284
af6359d5
ILT
1285 // These are relocations which should only be seen by the
1286 // dynamic linker, and should never be seen here.
92e059d8
ILT
1287 case elfcpp::R_386_COPY:
1288 case elfcpp::R_386_GLOB_DAT:
1289 case elfcpp::R_386_JUMP_SLOT:
1290 case elfcpp::R_386_RELATIVE:
1291 case elfcpp::R_386_TLS_TPOFF:
1292 case elfcpp::R_386_TLS_DTPMOD32:
1293 case elfcpp::R_386_TLS_DTPOFF32:
1294 case elfcpp::R_386_TLS_TPOFF32:
1295 case elfcpp::R_386_TLS_DESC:
75f2446e
ILT
1296 gold_error(_("%s: unexpected reloc %u in object file"),
1297 object->name().c_str(), r_type);
92e059d8
ILT
1298 break;
1299
d61c17ea
ILT
1300 // These are initial tls relocs, which are expected when
1301 // linking.
56622147
ILT
1302 case elfcpp::R_386_TLS_GD: // Global-dynamic
1303 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1304 case elfcpp::R_386_TLS_DESC_CALL:
1305 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1306 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1307 case elfcpp::R_386_TLS_IE: // Initial-exec
92e059d8 1308 case elfcpp::R_386_TLS_IE_32:
56622147
ILT
1309 case elfcpp::R_386_TLS_GOTIE:
1310 case elfcpp::R_386_TLS_LE: // Local-exec
92e059d8 1311 case elfcpp::R_386_TLS_LE_32:
a3ad94ed 1312 {
7e1edb90 1313 const bool is_final = gsym->final_value_is_known();
af6359d5
ILT
1314 const tls::Tls_optimization optimized_type
1315 = Target_i386::optimize_tls_reloc(is_final, r_type);
a3ad94ed
ILT
1316 switch (r_type)
1317 {
56622147 1318 case elfcpp::R_386_TLS_GD: // Global-dynamic
07f397ab
ILT
1319 if (optimized_type == tls::TLSOPT_NONE)
1320 {
1321 // Create a pair of GOT entries for the module index and
1322 // dtv-relative offset.
1323 Output_data_got<32, false>* got
1324 = target->got_section(symtab, layout);
0a65a3a7 1325 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
7bf1f802
ILT
1326 target->rel_dyn_section(layout),
1327 elfcpp::R_386_TLS_DTPMOD32,
1328 elfcpp::R_386_TLS_DTPOFF32);
07f397ab
ILT
1329 }
1330 else if (optimized_type == tls::TLSOPT_TO_IE)
1331 {
1332 // Create a GOT entry for the tp-relative offset.
1333 Output_data_got<32, false>* got
1334 = target->got_section(symtab, layout);
c2b45e22 1335 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
0a65a3a7 1336 target->rel_dyn_section(layout),
c2b45e22 1337 elfcpp::R_386_TLS_TPOFF);
07f397ab
ILT
1338 }
1339 else if (optimized_type != tls::TLSOPT_TO_LE)
1340 unsupported_reloc_global(object, r_type, gsym);
1341 break;
1342
56622147 1343 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (~oliva url)
edfbb029 1344 target->define_tls_base_symbol(symtab, layout);
c2b45e22
CC
1345 if (optimized_type == tls::TLSOPT_NONE)
1346 {
1347 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1348 Output_data_got<32, false>* got
1349 = target->got_section(symtab, layout);
1350 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC,
1351 target->rel_dyn_section(layout),
1352 elfcpp::R_386_TLS_DESC, 0);
1353 }
1354 else if (optimized_type == tls::TLSOPT_TO_IE)
1355 {
1356 // Create a GOT entry for the tp-relative offset.
1357 Output_data_got<32, false>* got
1358 = target->got_section(symtab, layout);
1359 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
1360 target->rel_dyn_section(layout),
1361 elfcpp::R_386_TLS_TPOFF);
1362 }
1363 else if (optimized_type != tls::TLSOPT_TO_LE)
7bf1f802 1364 unsupported_reloc_global(object, r_type, gsym);
c2b45e22
CC
1365 break;
1366
1367 case elfcpp::R_386_TLS_DESC_CALL:
af6359d5
ILT
1368 break;
1369
56622147 1370 case elfcpp::R_386_TLS_LDM: // Local-dynamic
07f397ab
ILT
1371 if (optimized_type == tls::TLSOPT_NONE)
1372 {
1373 // Create a GOT entry for the module index.
94c4710f 1374 target->got_mod_index_entry(symtab, layout, object);
07f397ab
ILT
1375 }
1376 else if (optimized_type != tls::TLSOPT_TO_LE)
af6359d5
ILT
1377 unsupported_reloc_global(object, r_type, gsym);
1378 break;
1379
56622147 1380 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
46cf9fa2
ILT
1381 break;
1382
56622147
ILT
1383 case elfcpp::R_386_TLS_IE: // Initial-exec
1384 case elfcpp::R_386_TLS_IE_32:
1385 case elfcpp::R_386_TLS_GOTIE:
535890bb 1386 layout->set_has_static_tls();
07f397ab
ILT
1387 if (optimized_type == tls::TLSOPT_NONE)
1388 {
7bf1f802
ILT
1389 // For the R_386_TLS_IE relocation, we need to create a
1390 // dynamic relocation when building a shared library.
1391 if (r_type == elfcpp::R_386_TLS_IE
8851ecca 1392 && parameters->options().shared())
07f397ab 1393 {
07f397ab 1394 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
e8c846c3
ILT
1395 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1396 output_section, object,
1397 data_shndx,
1398 reloc.get_r_offset());
07f397ab 1399 }
7bf1f802
ILT
1400 // Create a GOT entry for the tp-relative offset.
1401 Output_data_got<32, false>* got
1402 = target->got_section(symtab, layout);
1403 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1404 ? elfcpp::R_386_TLS_TPOFF32
1405 : elfcpp::R_386_TLS_TPOFF);
c2b45e22
CC
1406 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1407 ? GOT_TYPE_TLS_OFFSET
1408 : GOT_TYPE_TLS_NOFFSET);
1409 got->add_global_with_rel(gsym, got_type,
7bf1f802
ILT
1410 target->rel_dyn_section(layout),
1411 dyn_r_type);
07f397ab
ILT
1412 }
1413 else if (optimized_type != tls::TLSOPT_TO_LE)
af6359d5 1414 unsupported_reloc_global(object, r_type, gsym);
a3ad94ed 1415 break;
af6359d5 1416
56622147
ILT
1417 case elfcpp::R_386_TLS_LE: // Local-exec
1418 case elfcpp::R_386_TLS_LE_32:
535890bb 1419 layout->set_has_static_tls();
8851ecca 1420 if (parameters->options().shared())
7bf1f802
ILT
1421 {
1422 // We need to create a dynamic relocation.
1423 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1424 ? elfcpp::R_386_TLS_TPOFF32
1425 : elfcpp::R_386_TLS_TPOFF);
1426 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1427 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
1428 data_shndx, reloc.get_r_offset());
1429 }
56622147
ILT
1430 break;
1431
af6359d5
ILT
1432 default:
1433 gold_unreachable();
a3ad94ed
ILT
1434 }
1435 }
92e059d8
ILT
1436 break;
1437
92e059d8
ILT
1438 case elfcpp::R_386_32PLT:
1439 case elfcpp::R_386_TLS_GD_32:
1440 case elfcpp::R_386_TLS_GD_PUSH:
1441 case elfcpp::R_386_TLS_GD_CALL:
1442 case elfcpp::R_386_TLS_GD_POP:
1443 case elfcpp::R_386_TLS_LDM_32:
1444 case elfcpp::R_386_TLS_LDM_PUSH:
1445 case elfcpp::R_386_TLS_LDM_CALL:
1446 case elfcpp::R_386_TLS_LDM_POP:
1447 case elfcpp::R_386_USED_BY_INTEL_200:
1448 default:
af6359d5 1449 unsupported_reloc_global(object, r_type, gsym);
92e059d8
ILT
1450 break;
1451 }
1452}
1453
1454// Scan relocations for a section.
1455
1456void
1457Target_i386::scan_relocs(const General_options& options,
1458 Symbol_table* symtab,
ead1e424 1459 Layout* layout,
f6ce93d6 1460 Sized_relobj<32, false>* object,
a3ad94ed 1461 unsigned int data_shndx,
92e059d8
ILT
1462 unsigned int sh_type,
1463 const unsigned char* prelocs,
1464 size_t reloc_count,
730cdc88
ILT
1465 Output_section* output_section,
1466 bool needs_special_offset_handling,
92e059d8 1467 size_t local_symbol_count,
730cdc88 1468 const unsigned char* plocal_symbols)
92e059d8
ILT
1469{
1470 if (sh_type == elfcpp::SHT_RELA)
1471 {
75f2446e
ILT
1472 gold_error(_("%s: unsupported RELA reloc section"),
1473 object->name().c_str());
1474 return;
92e059d8
ILT
1475 }
1476
ead1e424
ILT
1477 gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
1478 Target_i386::Scan>(
92e059d8
ILT
1479 options,
1480 symtab,
ead1e424
ILT
1481 layout,
1482 this,
92e059d8 1483 object,
a3ad94ed 1484 data_shndx,
92e059d8
ILT
1485 prelocs,
1486 reloc_count,
730cdc88
ILT
1487 output_section,
1488 needs_special_offset_handling,
92e059d8 1489 local_symbol_count,
730cdc88 1490 plocal_symbols);
92e059d8
ILT
1491}
1492
16649710 1493// Finalize the sections.
5a6f7e2d
ILT
1494
1495void
7e1edb90 1496Target_i386::do_finalize_sections(Layout* layout)
5a6f7e2d 1497{
16649710
ILT
1498 // Fill in some more dynamic tags.
1499 Output_data_dynamic* const odyn = layout->dynamic_data();
1500 if (odyn != NULL)
1501 {
1502 if (this->got_plt_ != NULL)
1503 odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
1504
1505 if (this->plt_ != NULL)
1506 {
1507 const Output_data* od = this->plt_->rel_plt();
1508 odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
1509 odyn->add_section_address(elfcpp::DT_JMPREL, od);
1510 odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL);
1511 }
1512
1513 if (this->rel_dyn_ != NULL)
1514 {
1515 const Output_data* od = this->rel_dyn_;
1516 odyn->add_section_address(elfcpp::DT_REL, od);
1517 odyn->add_section_size(elfcpp::DT_RELSZ, od);
1518 odyn->add_constant(elfcpp::DT_RELENT,
1519 elfcpp::Elf_sizes<32>::rel_size);
1520 }
1521
8851ecca 1522 if (!parameters->options().shared())
16649710
ILT
1523 {
1524 // The value of the DT_DEBUG tag is filled in by the dynamic
1525 // linker at run time, and used by the debugger.
1526 odyn->add_constant(elfcpp::DT_DEBUG, 0);
1527 }
1528 }
1529
1530 // Emit any relocs we saved in an attempt to avoid generating COPY
1531 // relocs.
12c0daef
ILT
1532 if (this->copy_relocs_.any_saved_relocs())
1533 this->copy_relocs_.emit(this->rel_dyn_section(layout));
5a6f7e2d
ILT
1534}
1535
86849f1f
ILT
1536// Return whether a direct absolute static relocation needs to be applied.
1537// In cases where Scan::local() or Scan::global() has created
1538// a dynamic relocation other than R_386_RELATIVE, the addend
1539// of the relocation is carried in the data, and we must not
1540// apply the static relocation.
1541
1542inline bool
1543Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
0700cf32 1544 int ref_flags,
86849f1f
ILT
1545 bool is_32bit)
1546{
d61c6bd4
ILT
1547 // For local symbols, we will have created a non-RELATIVE dynamic
1548 // relocation only if (a) the output is position independent,
1549 // (b) the relocation is absolute (not pc- or segment-relative), and
1550 // (c) the relocation is not 32 bits wide.
86849f1f 1551 if (gsym == NULL)
8851ecca 1552 return !(parameters->options().output_is_position_independent()
0700cf32 1553 && (ref_flags & Symbol::ABSOLUTE_REF)
d61c6bd4 1554 && !is_32bit);
86849f1f 1555
0700cf32
ILT
1556 // For global symbols, we use the same helper routines used in the
1557 // scan pass. If we did not create a dynamic relocation, or if we
1558 // created a RELATIVE dynamic relocation, we should apply the static
1559 // relocation.
1560 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
1561 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
1562 && gsym->can_use_relative_reloc(ref_flags
1563 & Symbol::FUNCTION_CALL);
1564 return !has_dyn || is_rel;
86849f1f
ILT
1565}
1566
61ba1cf9
ILT
1567// Perform a relocation.
1568
ead1e424 1569inline bool
92e059d8 1570Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
ead1e424 1571 Target_i386* target,
92e059d8
ILT
1572 size_t relnum,
1573 const elfcpp::Rel<32, false>& rel,
1574 unsigned int r_type,
c06b7b0b 1575 const Sized_symbol<32>* gsym,
b8e6aad9 1576 const Symbol_value<32>* psymval,
92e059d8
ILT
1577 unsigned char* view,
1578 elfcpp::Elf_types<32>::Elf_Addr address,
fe8718a4 1579 section_size_type view_size)
61ba1cf9 1580{
ead1e424
ILT
1581 if (this->skip_call_tls_get_addr_)
1582 {
1583 if (r_type != elfcpp::R_386_PLT32
1584 || gsym == NULL
1585 || strcmp(gsym->name(), "___tls_get_addr") != 0)
75f2446e
ILT
1586 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1587 _("missing expected TLS relocation"));
1588 else
ead1e424 1589 {
75f2446e
ILT
1590 this->skip_call_tls_get_addr_ = false;
1591 return false;
ead1e424 1592 }
ead1e424
ILT
1593 }
1594
a3ad94ed 1595 // Pick the value to use for symbols defined in shared objects.
b8e6aad9 1596 Symbol_value<32> symval;
0700cf32
ILT
1597 bool is_nonpic = (r_type == elfcpp::R_386_PC8
1598 || r_type == elfcpp::R_386_PC16
1599 || r_type == elfcpp::R_386_PC32);
436ca963
ILT
1600 if (gsym != NULL
1601 && (gsym->is_from_dynobj()
8851ecca 1602 || (parameters->options().shared()
8fc19601 1603 && (gsym->is_undefined() || gsym->is_preemptible())))
0700cf32 1604 && gsym->has_plt_offset()
8851ecca 1605 && (!is_nonpic || !parameters->options().shared()))
a3ad94ed 1606 {
b8e6aad9
ILT
1607 symval.set_output_value(target->plt_section()->address()
1608 + gsym->plt_offset());
1609 psymval = &symval;
a3ad94ed
ILT
1610 }
1611
b8e6aad9
ILT
1612 const Sized_relobj<32, false>* object = relinfo->object;
1613
1b64748b 1614 // Get the GOT offset if needed.
96f2030e
ILT
1615 // The GOT pointer points to the end of the GOT section.
1616 // We need to subtract the size of the GOT section to get
1617 // the actual offset to use in the relocation.
1b64748b
ILT
1618 bool have_got_offset = false;
1619 unsigned int got_offset = 0;
1620 switch (r_type)
1621 {
1622 case elfcpp::R_386_GOT32:
1623 if (gsym != NULL)
1624 {
0a65a3a7
CC
1625 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
1626 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
1627 - target->got_size());
1b64748b
ILT
1628 }
1629 else
1630 {
1631 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
0a65a3a7
CC
1632 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
1633 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
1634 - target->got_size());
1b64748b
ILT
1635 }
1636 have_got_offset = true;
1637 break;
1638
1639 default:
1640 break;
1641 }
1642
61ba1cf9
ILT
1643 switch (r_type)
1644 {
1645 case elfcpp::R_386_NONE:
92e059d8
ILT
1646 case elfcpp::R_386_GNU_VTINHERIT:
1647 case elfcpp::R_386_GNU_VTENTRY:
61ba1cf9
ILT
1648 break;
1649
1650 case elfcpp::R_386_32:
0700cf32 1651 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true))
86849f1f 1652 Relocate_functions<32, false>::rel32(view, object, psymval);
61ba1cf9
ILT
1653 break;
1654
1655 case elfcpp::R_386_PC32:
d61c6bd4 1656 {
0700cf32
ILT
1657 int ref_flags = Symbol::NON_PIC_REF;
1658 if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC)
1659 ref_flags |= Symbol::FUNCTION_CALL;
1660 if (should_apply_static_reloc(gsym, ref_flags, true))
d61c6bd4
ILT
1661 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1662 }
92e059d8
ILT
1663 break;
1664
1665 case elfcpp::R_386_16:
0700cf32 1666 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false))
86849f1f 1667 Relocate_functions<32, false>::rel16(view, object, psymval);
92e059d8
ILT
1668 break;
1669
1670 case elfcpp::R_386_PC16:
d61c6bd4 1671 {
0700cf32
ILT
1672 int ref_flags = Symbol::NON_PIC_REF;
1673 if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC)
1674 ref_flags |= Symbol::FUNCTION_CALL;
1675 if (should_apply_static_reloc(gsym, ref_flags, false))
d09e9154 1676 Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
d61c6bd4 1677 }
61ba1cf9
ILT
1678 break;
1679
92e059d8 1680 case elfcpp::R_386_8:
0700cf32 1681 if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false))
86849f1f 1682 Relocate_functions<32, false>::rel8(view, object, psymval);
92e059d8
ILT
1683 break;
1684
1685 case elfcpp::R_386_PC8:
d61c6bd4 1686 {
0700cf32
ILT
1687 int ref_flags = Symbol::NON_PIC_REF;
1688 if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC)
1689 ref_flags |= Symbol::FUNCTION_CALL;
1690 if (should_apply_static_reloc(gsym, ref_flags, false))
d09e9154 1691 Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
d61c6bd4 1692 }
92e059d8
ILT
1693 break;
1694
ead1e424 1695 case elfcpp::R_386_PLT32:
df2efe71
ILT
1696 gold_assert(gsym == NULL
1697 || gsym->has_plt_offset()
99f8faca
ILT
1698 || gsym->final_value_is_known()
1699 || (gsym->is_defined()
1700 && !gsym->is_from_dynobj()
1701 && !gsym->is_preemptible()));
b8e6aad9 1702 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
ead1e424
ILT
1703 break;
1704
1705 case elfcpp::R_386_GOT32:
1b64748b
ILT
1706 gold_assert(have_got_offset);
1707 Relocate_functions<32, false>::rel32(view, got_offset);
ead1e424
ILT
1708 break;
1709
1710 case elfcpp::R_386_GOTOFF:
b8e6aad9
ILT
1711 {
1712 elfcpp::Elf_types<32>::Elf_Addr value;
1713 value = (psymval->value(object, 0)
96f2030e 1714 - target->got_plt_section()->address());
b8e6aad9
ILT
1715 Relocate_functions<32, false>::rel32(view, value);
1716 }
ead1e424
ILT
1717 break;
1718
1719 case elfcpp::R_386_GOTPC:
b8e6aad9
ILT
1720 {
1721 elfcpp::Elf_types<32>::Elf_Addr value;
96f2030e 1722 value = target->got_plt_section()->address();
b8e6aad9
ILT
1723 Relocate_functions<32, false>::pcrel32(view, value, address);
1724 }
ead1e424
ILT
1725 break;
1726
92e059d8
ILT
1727 case elfcpp::R_386_COPY:
1728 case elfcpp::R_386_GLOB_DAT:
1729 case elfcpp::R_386_JUMP_SLOT:
1730 case elfcpp::R_386_RELATIVE:
d61c17ea
ILT
1731 // These are outstanding tls relocs, which are unexpected when
1732 // linking.
92e059d8
ILT
1733 case elfcpp::R_386_TLS_TPOFF:
1734 case elfcpp::R_386_TLS_DTPMOD32:
1735 case elfcpp::R_386_TLS_DTPOFF32:
1736 case elfcpp::R_386_TLS_TPOFF32:
1737 case elfcpp::R_386_TLS_DESC:
75f2446e
ILT
1738 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1739 _("unexpected reloc %u in object file"),
1740 r_type);
92e059d8
ILT
1741 break;
1742
d61c17ea
ILT
1743 // These are initial tls relocs, which are expected when
1744 // linking.
56622147
ILT
1745 case elfcpp::R_386_TLS_GD: // Global-dynamic
1746 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1747 case elfcpp::R_386_TLS_DESC_CALL:
1748 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1749 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1750 case elfcpp::R_386_TLS_IE: // Initial-exec
92e059d8 1751 case elfcpp::R_386_TLS_IE_32:
56622147
ILT
1752 case elfcpp::R_386_TLS_GOTIE:
1753 case elfcpp::R_386_TLS_LE: // Local-exec
92e059d8 1754 case elfcpp::R_386_TLS_LE_32:
07f397ab
ILT
1755 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
1756 view, address, view_size);
92e059d8
ILT
1757 break;
1758
92e059d8
ILT
1759 case elfcpp::R_386_32PLT:
1760 case elfcpp::R_386_TLS_GD_32:
1761 case elfcpp::R_386_TLS_GD_PUSH:
1762 case elfcpp::R_386_TLS_GD_CALL:
1763 case elfcpp::R_386_TLS_GD_POP:
1764 case elfcpp::R_386_TLS_LDM_32:
1765 case elfcpp::R_386_TLS_LDM_PUSH:
1766 case elfcpp::R_386_TLS_LDM_CALL:
1767 case elfcpp::R_386_TLS_LDM_POP:
1768 case elfcpp::R_386_USED_BY_INTEL_200:
61ba1cf9 1769 default:
75f2446e
ILT
1770 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1771 _("unsupported reloc %u"),
1772 r_type);
92e059d8
ILT
1773 break;
1774 }
ead1e424
ILT
1775
1776 return true;
92e059d8
ILT
1777}
1778
1779// Perform a TLS relocation.
1780
1781inline void
1782Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
07f397ab 1783 Target_i386* target,
92e059d8
ILT
1784 size_t relnum,
1785 const elfcpp::Rel<32, false>& rel,
1786 unsigned int r_type,
c06b7b0b 1787 const Sized_symbol<32>* gsym,
b8e6aad9 1788 const Symbol_value<32>* psymval,
92e059d8
ILT
1789 unsigned char* view,
1790 elfcpp::Elf_types<32>::Elf_Addr,
fe8718a4 1791 section_size_type view_size)
92e059d8
ILT
1792{
1793 Output_segment* tls_segment = relinfo->layout->tls_segment();
92e059d8 1794
07f397ab
ILT
1795 const Sized_relobj<32, false>* object = relinfo->object;
1796
1797 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
b8e6aad9 1798
8851ecca
ILT
1799 const bool is_final =
1800 (gsym == NULL
1801 ? !parameters->options().output_is_position_independent()
1802 : gsym->final_value_is_known());
af6359d5
ILT
1803 const tls::Tls_optimization optimized_type
1804 = Target_i386::optimize_tls_reloc(is_final, r_type);
92e059d8
ILT
1805 switch (r_type)
1806 {
56622147 1807 case elfcpp::R_386_TLS_GD: // Global-dynamic
af6359d5 1808 if (optimized_type == tls::TLSOPT_TO_LE)
92e059d8 1809 {
07f397ab 1810 gold_assert(tls_segment != NULL);
56622147
ILT
1811 this->tls_gd_to_le(relinfo, relnum, tls_segment,
1812 rel, r_type, value, view,
1813 view_size);
92e059d8
ILT
1814 break;
1815 }
07f397ab
ILT
1816 else
1817 {
c2b45e22
CC
1818 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
1819 ? GOT_TYPE_TLS_NOFFSET
1820 : GOT_TYPE_TLS_PAIR);
07f397ab
ILT
1821 unsigned int got_offset;
1822 if (gsym != NULL)
1823 {
c2b45e22
CC
1824 gold_assert(gsym->has_got_offset(got_type));
1825 got_offset = gsym->got_offset(got_type) - target->got_size();
07f397ab
ILT
1826 }
1827 else
1828 {
1829 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
c2b45e22
CC
1830 gold_assert(object->local_has_got_offset(r_sym, got_type));
1831 got_offset = (object->local_got_offset(r_sym, got_type)
07f397ab
ILT
1832 - target->got_size());
1833 }
1834 if (optimized_type == tls::TLSOPT_TO_IE)
1835 {
1836 gold_assert(tls_segment != NULL);
7bf1f802
ILT
1837 this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
1838 got_offset, view, view_size);
07f397ab
ILT
1839 break;
1840 }
1841 else if (optimized_type == tls::TLSOPT_NONE)
1842 {
1843 // Relocate the field with the offset of the pair of GOT
1844 // entries.
1845 Relocate_functions<32, false>::rel32(view, got_offset);
1846 break;
1847 }
1848 }
75f2446e
ILT
1849 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1850 _("unsupported reloc %u"),
1851 r_type);
92e059d8
ILT
1852 break;
1853
56622147
ILT
1854 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1855 case elfcpp::R_386_TLS_DESC_CALL:
497897f9 1856 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
c2b45e22
CC
1857 if (optimized_type == tls::TLSOPT_TO_LE)
1858 {
1859 gold_assert(tls_segment != NULL);
1860 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
1861 rel, r_type, value, view,
1862 view_size);
1863 break;
1864 }
1865 else
1866 {
1867 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
1868 ? GOT_TYPE_TLS_NOFFSET
1869 : GOT_TYPE_TLS_DESC);
1870 unsigned int got_offset;
1871 if (gsym != NULL)
1872 {
1873 gold_assert(gsym->has_got_offset(got_type));
1874 got_offset = gsym->got_offset(got_type) - target->got_size();
1875 }
1876 else
1877 {
1878 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1879 gold_assert(object->local_has_got_offset(r_sym, got_type));
1880 got_offset = (object->local_got_offset(r_sym, got_type)
1881 - target->got_size());
1882 }
1883 if (optimized_type == tls::TLSOPT_TO_IE)
1884 {
1885 gold_assert(tls_segment != NULL);
1886 this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
1887 got_offset, view, view_size);
1888 break;
1889 }
1890 else if (optimized_type == tls::TLSOPT_NONE)
1891 {
1892 if (r_type == elfcpp::R_386_TLS_GOTDESC)
1893 {
1894 // Relocate the field with the offset of the pair of GOT
1895 // entries.
1896 Relocate_functions<32, false>::rel32(view, got_offset);
1897 }
1898 break;
1899 }
1900 }
75f2446e
ILT
1901 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1902 _("unsupported reloc %u"),
1903 r_type);
ead1e424
ILT
1904 break;
1905
56622147 1906 case elfcpp::R_386_TLS_LDM: // Local-dynamic
46cf9fa2
ILT
1907 if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
1908 {
75f2446e
ILT
1909 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1910 _("both SUN and GNU model "
1911 "TLS relocations"));
1912 break;
46cf9fa2
ILT
1913 }
1914 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
af6359d5 1915 if (optimized_type == tls::TLSOPT_TO_LE)
46cf9fa2 1916 {
07f397ab 1917 gold_assert(tls_segment != NULL);
46cf9fa2
ILT
1918 this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
1919 value, view, view_size);
1920 break;
1921 }
07f397ab
ILT
1922 else if (optimized_type == tls::TLSOPT_NONE)
1923 {
1924 // Relocate the field with the offset of the GOT entry for
1925 // the module index.
1926 unsigned int got_offset;
94c4710f
ILT
1927 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
1928 - target->got_size());
07f397ab
ILT
1929 Relocate_functions<32, false>::rel32(view, got_offset);
1930 break;
1931 }
75f2446e
ILT
1932 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1933 _("unsupported reloc %u"),
1934 r_type);
46cf9fa2
ILT
1935 break;
1936
56622147 1937 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
46cf9fa2
ILT
1938 // This reloc can appear in debugging sections, in which case we
1939 // won't see the TLS_LDM reloc. The local_dynamic_type field
1940 // tells us this.
497897f9
ILT
1941 if (optimized_type == tls::TLSOPT_TO_LE
1942 && this->local_dynamic_type_ != LOCAL_DYNAMIC_NONE)
94c4710f
ILT
1943 {
1944 gold_assert(tls_segment != NULL);
1945 value -= tls_segment->memsz();
1946 }
46cf9fa2
ILT
1947 Relocate_functions<32, false>::rel32(view, value);
1948 break;
1949
56622147
ILT
1950 case elfcpp::R_386_TLS_IE: // Initial-exec
1951 case elfcpp::R_386_TLS_GOTIE:
1952 case elfcpp::R_386_TLS_IE_32:
1953 if (optimized_type == tls::TLSOPT_TO_LE)
1954 {
07f397ab 1955 gold_assert(tls_segment != NULL);
56622147
ILT
1956 Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
1957 rel, r_type, value, view,
1958 view_size);
1959 break;
1960 }
07f397ab
ILT
1961 else if (optimized_type == tls::TLSOPT_NONE)
1962 {
1963 // Relocate the field with the offset of the GOT entry for
1964 // the tp-relative offset of the symbol.
c2b45e22
CC
1965 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1966 ? GOT_TYPE_TLS_OFFSET
1967 : GOT_TYPE_TLS_NOFFSET);
07f397ab
ILT
1968 unsigned int got_offset;
1969 if (gsym != NULL)
1970 {
c2b45e22
CC
1971 gold_assert(gsym->has_got_offset(got_type));
1972 got_offset = gsym->got_offset(got_type);
07f397ab
ILT
1973 }
1974 else
1975 {
1976 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
c2b45e22
CC
1977 gold_assert(object->local_has_got_offset(r_sym, got_type));
1978 got_offset = object->local_got_offset(r_sym, got_type);
07f397ab
ILT
1979 }
1980 // For the R_386_TLS_IE relocation, we need to apply the
1981 // absolute address of the GOT entry.
1982 if (r_type == elfcpp::R_386_TLS_IE)
1983 got_offset += target->got_plt_section()->address();
1984 // All GOT offsets are relative to the end of the GOT.
1985 got_offset -= target->got_size();
1986 Relocate_functions<32, false>::rel32(view, got_offset);
1987 break;
1988 }
75f2446e
ILT
1989 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1990 _("unsupported reloc %u"),
1991 r_type);
92e059d8 1992 break;
92e059d8 1993
56622147 1994 case elfcpp::R_386_TLS_LE: // Local-exec
7bf1f802
ILT
1995 // If we're creating a shared library, a dynamic relocation will
1996 // have been created for this location, so do not apply it now.
8851ecca 1997 if (!parameters->options().shared())
7bf1f802
ILT
1998 {
1999 gold_assert(tls_segment != NULL);
2000 value -= tls_segment->memsz();
2001 Relocate_functions<32, false>::rel32(view, value);
2002 }
56622147 2003 break;
92e059d8 2004
56622147 2005 case elfcpp::R_386_TLS_LE_32:
7bf1f802
ILT
2006 // If we're creating a shared library, a dynamic relocation will
2007 // have been created for this location, so do not apply it now.
8851ecca 2008 if (!parameters->options().shared())
7bf1f802
ILT
2009 {
2010 gold_assert(tls_segment != NULL);
2011 value = tls_segment->memsz() - value;
2012 Relocate_functions<32, false>::rel32(view, value);
2013 }
56622147 2014 break;
92e059d8 2015 }
92e059d8
ILT
2016}
2017
e041f13d 2018// Do a relocation in which we convert a TLS General-Dynamic to a
ead1e424
ILT
2019// Local-Exec.
2020
2021inline void
2022Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
2023 size_t relnum,
2024 Output_segment* tls_segment,
2025 const elfcpp::Rel<32, false>& rel,
2026 unsigned int,
2027 elfcpp::Elf_types<32>::Elf_Addr value,
2028 unsigned char* view,
fe8718a4 2029 section_size_type view_size)
ead1e424
ILT
2030{
2031 // leal foo(,%reg,1),%eax; call ___tls_get_addr
46cf9fa2 2032 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
ead1e424
ILT
2033 // leal foo(%reg),%eax; call ___tls_get_addr
2034 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2035
af6359d5
ILT
2036 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2037 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
ead1e424
ILT
2038
2039 unsigned char op1 = view[-1];
2040 unsigned char op2 = view[-2];
2041
af6359d5
ILT
2042 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2043 op2 == 0x8d || op2 == 0x04);
2044 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
ead1e424
ILT
2045
2046 int roff = 5;
2047
2048 if (op2 == 0x04)
2049 {
af6359d5
ILT
2050 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
2051 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
2052 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2053 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
ead1e424
ILT
2054 memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2055 }
2056 else
2057 {
af6359d5
ILT
2058 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2059 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
fe8718a4 2060 if (rel.get_r_offset() + 9 < view_size
d61c17ea 2061 && view[9] == 0x90)
ead1e424
ILT
2062 {
2063 // There is a trailing nop. Use the size byte subl.
2064 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2065 roff = 6;
2066 }
2067 else
2068 {
2069 // Use the five byte subl.
2070 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2071 }
2072 }
2073
7bf1f802 2074 value = tls_segment->memsz() - value;
ead1e424
ILT
2075 Relocate_functions<32, false>::rel32(view + roff, value);
2076
2077 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2078 // We can skip it.
2079 this->skip_call_tls_get_addr_ = true;
2080}
2081
7bf1f802 2082// Do a relocation in which we convert a TLS General-Dynamic to an
07f397ab
ILT
2083// Initial-Exec.
2084
2085inline void
2086Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
2087 size_t relnum,
c2b45e22 2088 Output_segment*,
07f397ab
ILT
2089 const elfcpp::Rel<32, false>& rel,
2090 unsigned int,
2091 elfcpp::Elf_types<32>::Elf_Addr value,
2092 unsigned char* view,
fe8718a4 2093 section_size_type view_size)
07f397ab
ILT
2094{
2095 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2096 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2097
2098 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2099 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2100
2101 unsigned char op1 = view[-1];
2102 unsigned char op2 = view[-2];
2103
2104 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2105 op2 == 0x8d || op2 == 0x04);
2106 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2107
2108 int roff = 5;
2109
c2b45e22
CC
2110 // FIXME: For now, support only the first (SIB) form.
2111 tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x04);
07f397ab
ILT
2112
2113 if (op2 == 0x04)
2114 {
2115 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
2116 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
2117 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2118 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
2119 memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2120 }
2121 else
2122 {
2123 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2124 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
fe8718a4 2125 if (rel.get_r_offset() + 9 < view_size
07f397ab
ILT
2126 && view[9] == 0x90)
2127 {
2128 // FIXME: This is not the right instruction sequence.
2129 // There is a trailing nop. Use the size byte subl.
2130 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2131 roff = 6;
2132 }
2133 else
2134 {
2135 // FIXME: This is not the right instruction sequence.
2136 // Use the five byte subl.
2137 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2138 }
2139 }
2140
07f397ab
ILT
2141 Relocate_functions<32, false>::rel32(view + roff, value);
2142
2143 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2144 // We can skip it.
2145 this->skip_call_tls_get_addr_ = true;
2146}
2147
c2b45e22
CC
2148// Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2149// General-Dynamic to a Local-Exec.
2150
2151inline void
2152Target_i386::Relocate::tls_desc_gd_to_le(
2153 const Relocate_info<32, false>* relinfo,
2154 size_t relnum,
2155 Output_segment* tls_segment,
2156 const elfcpp::Rel<32, false>& rel,
2157 unsigned int r_type,
2158 elfcpp::Elf_types<32>::Elf_Addr value,
2159 unsigned char* view,
2160 section_size_type view_size)
2161{
2162 if (r_type == elfcpp::R_386_TLS_GOTDESC)
2163 {
2164 // leal foo@TLSDESC(%ebx), %eax
2165 // ==> leal foo@NTPOFF, %eax
2166 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2167 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2168 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2169 view[-2] == 0x8d && view[-1] == 0x83);
2170 view[-1] = 0x05;
2171 value -= tls_segment->memsz();
2172 Relocate_functions<32, false>::rel32(view, value);
2173 }
2174 else
2175 {
2176 // call *foo@TLSCALL(%eax)
2177 // ==> nop; nop
2178 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
2179 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
2180 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2181 view[0] == 0xff && view[1] == 0x10);
2182 view[0] = 0x66;
2183 view[1] = 0x90;
2184 }
2185}
2186
2187// Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2188// General-Dynamic to an Initial-Exec.
2189
2190inline void
2191Target_i386::Relocate::tls_desc_gd_to_ie(
2192 const Relocate_info<32, false>* relinfo,
2193 size_t relnum,
2194 Output_segment*,
2195 const elfcpp::Rel<32, false>& rel,
2196 unsigned int r_type,
2197 elfcpp::Elf_types<32>::Elf_Addr value,
2198 unsigned char* view,
2199 section_size_type view_size)
2200{
2201 if (r_type == elfcpp::R_386_TLS_GOTDESC)
2202 {
2203 // leal foo@TLSDESC(%ebx), %eax
2204 // ==> movl foo@GOTNTPOFF(%ebx), %eax
2205 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2206 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2207 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2208 view[-2] == 0x8d && view[-1] == 0x83);
2209 view[-2] = 0x8b;
2210 Relocate_functions<32, false>::rel32(view, value);
2211 }
2212 else
2213 {
2214 // call *foo@TLSCALL(%eax)
2215 // ==> nop; nop
2216 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
2217 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
2218 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2219 view[0] == 0xff && view[1] == 0x10);
2220 view[0] = 0x66;
2221 view[1] = 0x90;
2222 }
2223}
2224
46cf9fa2
ILT
2225// Do a relocation in which we convert a TLS Local-Dynamic to a
2226// Local-Exec.
2227
2228inline void
2229Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
2230 size_t relnum,
2231 Output_segment*,
2232 const elfcpp::Rel<32, false>& rel,
2233 unsigned int,
2234 elfcpp::Elf_types<32>::Elf_Addr,
2235 unsigned char* view,
fe8718a4 2236 section_size_type view_size)
46cf9fa2
ILT
2237{
2238 // leal foo(%reg), %eax; call ___tls_get_addr
2239 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2240
af6359d5
ILT
2241 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2242 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
46cf9fa2
ILT
2243
2244 // FIXME: Does this test really always pass?
af6359d5
ILT
2245 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2246 view[-2] == 0x8d && view[-1] == 0x83);
46cf9fa2 2247
af6359d5 2248 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
46cf9fa2
ILT
2249
2250 memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2251
2252 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2253 // We can skip it.
2254 this->skip_call_tls_get_addr_ = true;
2255}
2256
56622147
ILT
2257// Do a relocation in which we convert a TLS Initial-Exec to a
2258// Local-Exec.
2259
2260inline void
2261Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
2262 size_t relnum,
2263 Output_segment* tls_segment,
2264 const elfcpp::Rel<32, false>& rel,
2265 unsigned int r_type,
2266 elfcpp::Elf_types<32>::Elf_Addr value,
2267 unsigned char* view,
fe8718a4 2268 section_size_type view_size)
56622147
ILT
2269{
2270 // We have to actually change the instructions, which means that we
2271 // need to examine the opcodes to figure out which instruction we
2272 // are looking at.
2273 if (r_type == elfcpp::R_386_TLS_IE)
2274 {
2275 // movl %gs:XX,%eax ==> movl $YY,%eax
2276 // movl %gs:XX,%reg ==> movl $YY,%reg
2277 // addl %gs:XX,%reg ==> addl $YY,%reg
2278 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
2279 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2280
2281 unsigned char op1 = view[-1];
2282 if (op1 == 0xa1)
2283 {
2284 // movl XX,%eax ==> movl $YY,%eax
2285 view[-1] = 0xb8;
2286 }
2287 else
2288 {
2289 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2290
2291 unsigned char op2 = view[-2];
2292 if (op2 == 0x8b)
2293 {
2294 // movl XX,%reg ==> movl $YY,%reg
2295 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2296 (op1 & 0xc7) == 0x05);
2297 view[-2] = 0xc7;
2298 view[-1] = 0xc0 | ((op1 >> 3) & 7);
2299 }
2300 else if (op2 == 0x03)
2301 {
2302 // addl XX,%reg ==> addl $YY,%reg
2303 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2304 (op1 & 0xc7) == 0x05);
2305 view[-2] = 0x81;
2306 view[-1] = 0xc0 | ((op1 >> 3) & 7);
2307 }
2308 else
2309 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2310 }
2311 }
2312 else
2313 {
2314 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2315 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2316 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2317 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2318 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2319
2320 unsigned char op1 = view[-1];
2321 unsigned char op2 = view[-2];
2322 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2323 (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
2324 if (op2 == 0x8b)
2325 {
2326 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2327 view[-2] = 0xc7;
2328 view[-1] = 0xc0 | ((op1 >> 3) & 7);
2329 }
2330 else if (op2 == 0x2b)
2331 {
2332 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2333 view[-2] = 0x81;
2334 view[-1] = 0xe8 | ((op1 >> 3) & 7);
2335 }
2336 else if (op2 == 0x03)
2337 {
2338 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2339 view[-2] = 0x81;
2340 view[-1] = 0xc0 | ((op1 >> 3) & 7);
2341 }
2342 else
2343 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2344 }
2345
7bf1f802 2346 value = tls_segment->memsz() - value;
56622147
ILT
2347 if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
2348 value = - value;
2349
2350 Relocate_functions<32, false>::rel32(view, value);
2351}
2352
61ba1cf9
ILT
2353// Relocate section data.
2354
2355void
92e059d8 2356Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
61ba1cf9
ILT
2357 unsigned int sh_type,
2358 const unsigned char* prelocs,
2359 size_t reloc_count,
730cdc88
ILT
2360 Output_section* output_section,
2361 bool needs_special_offset_handling,
61ba1cf9
ILT
2362 unsigned char* view,
2363 elfcpp::Elf_types<32>::Elf_Addr address,
fe8718a4 2364 section_size_type view_size)
61ba1cf9 2365{
a3ad94ed 2366 gold_assert(sh_type == elfcpp::SHT_REL);
61ba1cf9 2367
ead1e424
ILT
2368 gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
2369 Target_i386::Relocate>(
92e059d8 2370 relinfo,
ead1e424 2371 this,
61ba1cf9
ILT
2372 prelocs,
2373 reloc_count,
730cdc88
ILT
2374 output_section,
2375 needs_special_offset_handling,
61ba1cf9
ILT
2376 view,
2377 address,
2378 view_size);
2379}
2380
6a74a719
ILT
2381// Return the size of a relocation while scanning during a relocatable
2382// link.
2383
2384unsigned int
2385Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
2386 unsigned int r_type,
2387 Relobj* object)
2388{
2389 switch (r_type)
2390 {
2391 case elfcpp::R_386_NONE:
2392 case elfcpp::R_386_GNU_VTINHERIT:
2393 case elfcpp::R_386_GNU_VTENTRY:
2394 case elfcpp::R_386_TLS_GD: // Global-dynamic
2395 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2396 case elfcpp::R_386_TLS_DESC_CALL:
2397 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2398 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2399 case elfcpp::R_386_TLS_IE: // Initial-exec
2400 case elfcpp::R_386_TLS_IE_32:
2401 case elfcpp::R_386_TLS_GOTIE:
2402 case elfcpp::R_386_TLS_LE: // Local-exec
2403 case elfcpp::R_386_TLS_LE_32:
2404 return 0;
2405
2406 case elfcpp::R_386_32:
2407 case elfcpp::R_386_PC32:
2408 case elfcpp::R_386_GOT32:
2409 case elfcpp::R_386_PLT32:
2410 case elfcpp::R_386_GOTOFF:
2411 case elfcpp::R_386_GOTPC:
2412 return 4;
2413
2414 case elfcpp::R_386_16:
2415 case elfcpp::R_386_PC16:
2416 return 2;
2417
2418 case elfcpp::R_386_8:
2419 case elfcpp::R_386_PC8:
2420 return 1;
2421
2422 // These are relocations which should only be seen by the
2423 // dynamic linker, and should never be seen here.
2424 case elfcpp::R_386_COPY:
2425 case elfcpp::R_386_GLOB_DAT:
2426 case elfcpp::R_386_JUMP_SLOT:
2427 case elfcpp::R_386_RELATIVE:
2428 case elfcpp::R_386_TLS_TPOFF:
2429 case elfcpp::R_386_TLS_DTPMOD32:
2430 case elfcpp::R_386_TLS_DTPOFF32:
2431 case elfcpp::R_386_TLS_TPOFF32:
2432 case elfcpp::R_386_TLS_DESC:
2433 object->error(_("unexpected reloc %u in object file"), r_type);
2434 return 0;
2435
2436 case elfcpp::R_386_32PLT:
2437 case elfcpp::R_386_TLS_GD_32:
2438 case elfcpp::R_386_TLS_GD_PUSH:
2439 case elfcpp::R_386_TLS_GD_CALL:
2440 case elfcpp::R_386_TLS_GD_POP:
2441 case elfcpp::R_386_TLS_LDM_32:
2442 case elfcpp::R_386_TLS_LDM_PUSH:
2443 case elfcpp::R_386_TLS_LDM_CALL:
2444 case elfcpp::R_386_TLS_LDM_POP:
2445 case elfcpp::R_386_USED_BY_INTEL_200:
2446 default:
2447 object->error(_("unsupported reloc %u in object file"), r_type);
2448 return 0;
2449 }
2450}
2451
2452// Scan the relocs during a relocatable link.
2453
2454void
2455Target_i386::scan_relocatable_relocs(const General_options& options,
2456 Symbol_table* symtab,
2457 Layout* layout,
2458 Sized_relobj<32, false>* object,
2459 unsigned int data_shndx,
2460 unsigned int sh_type,
2461 const unsigned char* prelocs,
2462 size_t reloc_count,
2463 Output_section* output_section,
2464 bool needs_special_offset_handling,
2465 size_t local_symbol_count,
2466 const unsigned char* plocal_symbols,
2467 Relocatable_relocs* rr)
2468{
2469 gold_assert(sh_type == elfcpp::SHT_REL);
2470
2471 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
2472 Relocatable_size_for_reloc> Scan_relocatable_relocs;
2473
7019cd25 2474 gold::scan_relocatable_relocs<32, false, elfcpp::SHT_REL,
6a74a719
ILT
2475 Scan_relocatable_relocs>(
2476 options,
2477 symtab,
2478 layout,
2479 object,
2480 data_shndx,
2481 prelocs,
2482 reloc_count,
2483 output_section,
2484 needs_special_offset_handling,
2485 local_symbol_count,
2486 plocal_symbols,
2487 rr);
2488}
2489
2490// Relocate a section during a relocatable link.
2491
2492void
2493Target_i386::relocate_for_relocatable(
2494 const Relocate_info<32, false>* relinfo,
2495 unsigned int sh_type,
2496 const unsigned char* prelocs,
2497 size_t reloc_count,
2498 Output_section* output_section,
2499 off_t offset_in_output_section,
2500 const Relocatable_relocs* rr,
2501 unsigned char* view,
2502 elfcpp::Elf_types<32>::Elf_Addr view_address,
2503 section_size_type view_size,
2504 unsigned char* reloc_view,
2505 section_size_type reloc_view_size)
2506{
2507 gold_assert(sh_type == elfcpp::SHT_REL);
2508
7019cd25 2509 gold::relocate_for_relocatable<32, false, elfcpp::SHT_REL>(
6a74a719
ILT
2510 relinfo,
2511 prelocs,
2512 reloc_count,
2513 output_section,
2514 offset_in_output_section,
2515 rr,
2516 view,
2517 view_address,
2518 view_size,
2519 reloc_view,
2520 reloc_view_size);
2521}
2522
ab5c9e90
ILT
2523// Return the value to use for a dynamic which requires special
2524// treatment. This is how we support equality comparisons of function
2525// pointers across shared library boundaries, as described in the
2526// processor specific ABI supplement.
2527
2528uint64_t
2529Target_i386::do_dynsym_value(const Symbol* gsym) const
2530{
2531 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
2532 return this->plt_section()->address() + gsym->plt_offset();
2533}
2534
c51e6221
ILT
2535// Return a string used to fill a code section with nops to take up
2536// the specified length.
2537
2538std::string
8851ecca 2539Target_i386::do_code_fill(section_size_type length) const
c51e6221
ILT
2540{
2541 if (length >= 16)
2542 {
2543 // Build a jmp instruction to skip over the bytes.
2544 unsigned char jmp[5];
2545 jmp[0] = 0xe9;
2546 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
2547 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
2548 + std::string(length - 5, '\0'));
2549 }
2550
2551 // Nop sequences of various lengths.
2552 const char nop1[1] = { 0x90 }; // nop
2553 const char nop2[2] = { 0x66, 0x90 }; // xchg %ax %ax
2554 const char nop3[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2555 const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2556 const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2557 0x00 }; // leal 0(%esi,1),%esi
2558 const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2559 0x00, 0x00 };
2560 const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2561 0x00, 0x00, 0x00 };
2562 const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2563 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2564 const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2565 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2566 0x00 };
2567 const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2568 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2569 0x00, 0x00 };
2570 const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2571 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2572 0x00, 0x00, 0x00 };
2573 const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2574 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2575 0x00, 0x00, 0x00, 0x00 };
2576 const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2577 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2578 0x27, 0x00, 0x00, 0x00,
2579 0x00 };
2580 const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2581 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2582 0xbc, 0x27, 0x00, 0x00,
2583 0x00, 0x00 };
2584 const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2585 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2586 0x90, 0x90, 0x90, 0x90,
2587 0x90, 0x90, 0x90 };
2588
2589 const char* nops[16] = {
2590 NULL,
2591 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
2592 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
2593 };
2594
2595 return std::string(nops[length], length);
2596}
2597
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ILT
2598// The selector for i386 object files.
2599
2600class Target_selector_i386 : public Target_selector
2601{
2602public:
2603 Target_selector_i386()
e96caa79 2604 : Target_selector(elfcpp::EM_386, 32, false, "elf32-i386")
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ILT
2605 { }
2606
2607 Target*
e96caa79
ILT
2608 do_instantiate_target()
2609 { return new Target_i386(); }
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ILT
2610};
2611
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ILT
2612Target_selector_i386 target_selector_i386;
2613
2614} // End anonymous namespace.
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