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14bfc3f5 ILT |
1 | // i386.cc -- i386 target support for gold. |
2 | ||
6cb15b7f ILT |
3 | // Copyright 2006, 2007 Free Software Foundation, Inc. |
4 | // Written by Ian Lance Taylor <iant@google.com>. | |
5 | ||
6 | // This file is part of gold. | |
7 | ||
8 | // This program is free software; you can redistribute it and/or modify | |
9 | // it under the terms of the GNU General Public License as published by | |
10 | // the Free Software Foundation; either version 3 of the License, or | |
11 | // (at your option) any later version. | |
12 | ||
13 | // This program is distributed in the hope that it will be useful, | |
14 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | // GNU General Public License for more details. | |
17 | ||
18 | // You should have received a copy of the GNU General Public License | |
19 | // along with this program; if not, write to the Free Software | |
20 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, | |
21 | // MA 02110-1301, USA. | |
22 | ||
14bfc3f5 | 23 | #include "gold.h" |
ead1e424 ILT |
24 | |
25 | #include <cstring> | |
26 | ||
14bfc3f5 | 27 | #include "elfcpp.h" |
7e1edb90 | 28 | #include "parameters.h" |
92e059d8 | 29 | #include "reloc.h" |
61ba1cf9 ILT |
30 | #include "i386.h" |
31 | #include "object.h" | |
ead1e424 | 32 | #include "symtab.h" |
92e059d8 ILT |
33 | #include "layout.h" |
34 | #include "output.h" | |
14bfc3f5 | 35 | #include "target.h" |
61ba1cf9 | 36 | #include "target-reloc.h" |
14bfc3f5 | 37 | #include "target-select.h" |
af6359d5 | 38 | #include "tls.h" |
14bfc3f5 ILT |
39 | |
40 | namespace | |
41 | { | |
42 | ||
43 | using namespace gold; | |
44 | ||
a3ad94ed ILT |
45 | class Output_data_plt_i386; |
46 | ||
14bfc3f5 ILT |
47 | // The i386 target class. |
48 | ||
49 | class Target_i386 : public Sized_target<32, false> | |
50 | { | |
51 | public: | |
5a6f7e2d ILT |
52 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section; |
53 | ||
14bfc3f5 | 54 | Target_i386() |
ead1e424 | 55 | : Sized_target<32, false>(&i386_info), |
5a6f7e2d ILT |
56 | got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), |
57 | copy_relocs_(NULL), dynbss_(NULL) | |
14bfc3f5 | 58 | { } |
75f65a3e | 59 | |
92e059d8 | 60 | // Scan the relocations to look for symbol adjustments. |
61ba1cf9 | 61 | void |
92e059d8 ILT |
62 | scan_relocs(const General_options& options, |
63 | Symbol_table* symtab, | |
ead1e424 | 64 | Layout* layout, |
f6ce93d6 | 65 | Sized_relobj<32, false>* object, |
a3ad94ed | 66 | unsigned int data_shndx, |
92e059d8 ILT |
67 | unsigned int sh_type, |
68 | const unsigned char* prelocs, | |
69 | size_t reloc_count, | |
70 | size_t local_symbol_count, | |
71 | const unsigned char* plocal_symbols, | |
72 | Symbol** global_symbols); | |
61ba1cf9 | 73 | |
5a6f7e2d ILT |
74 | // Finalize the sections. |
75 | void | |
7e1edb90 | 76 | do_finalize_sections(Layout*); |
5a6f7e2d | 77 | |
ab5c9e90 ILT |
78 | // Return the value to use for a dynamic which requires special |
79 | // treatment. | |
80 | uint64_t | |
81 | do_dynsym_value(const Symbol*) const; | |
82 | ||
92e059d8 ILT |
83 | // Relocate a section. |
84 | void | |
85 | relocate_section(const Relocate_info<32, false>*, | |
86 | unsigned int sh_type, | |
87 | const unsigned char* prelocs, | |
88 | size_t reloc_count, | |
89 | unsigned char* view, | |
90 | elfcpp::Elf_types<32>::Elf_Addr view_address, | |
91 | off_t view_size); | |
92 | ||
c51e6221 ILT |
93 | // Return a string used to fill a code section with nops. |
94 | std::string | |
95 | do_code_fill(off_t length); | |
96 | ||
92e059d8 ILT |
97 | private: |
98 | // The class which scans relocations. | |
99 | struct Scan | |
61ba1cf9 ILT |
100 | { |
101 | inline void | |
ead1e424 ILT |
102 | local(const General_options& options, Symbol_table* symtab, |
103 | Layout* layout, Target_i386* target, | |
f6ce93d6 | 104 | Sized_relobj<32, false>* object, |
a3ad94ed | 105 | unsigned int data_shndx, |
92e059d8 ILT |
106 | const elfcpp::Rel<32, false>& reloc, unsigned int r_type, |
107 | const elfcpp::Sym<32, false>& lsym); | |
61ba1cf9 | 108 | |
92e059d8 | 109 | inline void |
ead1e424 ILT |
110 | global(const General_options& options, Symbol_table* symtab, |
111 | Layout* layout, Target_i386* target, | |
f6ce93d6 | 112 | Sized_relobj<32, false>* object, |
a3ad94ed | 113 | unsigned int data_shndx, |
92e059d8 ILT |
114 | const elfcpp::Rel<32, false>& reloc, unsigned int r_type, |
115 | Symbol* gsym); | |
af6359d5 ILT |
116 | |
117 | static void | |
118 | unsupported_reloc_local(Sized_relobj<32, false>*, unsigned int r_type); | |
119 | ||
120 | static void | |
121 | unsupported_reloc_global(Sized_relobj<32, false>*, unsigned int r_type, | |
122 | Symbol*); | |
61ba1cf9 ILT |
123 | }; |
124 | ||
92e059d8 ILT |
125 | // The class which implements relocation. |
126 | class Relocate | |
127 | { | |
128 | public: | |
ead1e424 | 129 | Relocate() |
46cf9fa2 ILT |
130 | : skip_call_tls_get_addr_(false), |
131 | local_dynamic_type_(LOCAL_DYNAMIC_NONE) | |
ead1e424 ILT |
132 | { } |
133 | ||
134 | ~Relocate() | |
135 | { | |
136 | if (this->skip_call_tls_get_addr_) | |
137 | { | |
138 | // FIXME: This needs to specify the location somehow. | |
139 | fprintf(stderr, _("%s: missing expected TLS relocation\n"), | |
140 | program_name); | |
141 | gold_exit(false); | |
142 | } | |
143 | } | |
144 | ||
145 | // Do a relocation. Return false if the caller should not issue | |
146 | // any warnings about this relocation. | |
147 | inline bool | |
148 | relocate(const Relocate_info<32, false>*, Target_i386*, size_t relnum, | |
92e059d8 | 149 | const elfcpp::Rel<32, false>&, |
c06b7b0b | 150 | unsigned int r_type, const Sized_symbol<32>*, |
b8e6aad9 | 151 | const Symbol_value<32>*, |
92e059d8 ILT |
152 | unsigned char*, elfcpp::Elf_types<32>::Elf_Addr, |
153 | off_t); | |
154 | ||
155 | private: | |
156 | // Do a TLS relocation. | |
ead1e424 | 157 | inline void |
92e059d8 ILT |
158 | relocate_tls(const Relocate_info<32, false>*, size_t relnum, |
159 | const elfcpp::Rel<32, false>&, | |
c06b7b0b | 160 | unsigned int r_type, const Sized_symbol<32>*, |
b8e6aad9 | 161 | const Symbol_value<32>*, |
92e059d8 ILT |
162 | unsigned char*, elfcpp::Elf_types<32>::Elf_Addr, off_t); |
163 | ||
164 | // Do a TLS Initial-Exec to Local-Exec transition. | |
165 | static inline void | |
166 | tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum, | |
167 | Output_segment* tls_segment, | |
168 | const elfcpp::Rel<32, false>&, unsigned int r_type, | |
169 | elfcpp::Elf_types<32>::Elf_Addr value, | |
170 | unsigned char* view, | |
171 | off_t view_size); | |
172 | ||
ead1e424 ILT |
173 | // Do a TLS Global-Dynamic to Local-Exec transition. |
174 | inline void | |
175 | tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum, | |
176 | Output_segment* tls_segment, | |
177 | const elfcpp::Rel<32, false>&, unsigned int r_type, | |
178 | elfcpp::Elf_types<32>::Elf_Addr value, | |
179 | unsigned char* view, | |
180 | off_t view_size); | |
181 | ||
46cf9fa2 ILT |
182 | // Do a TLS Local-Dynamic to Local-Exec transition. |
183 | inline void | |
184 | tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum, | |
185 | Output_segment* tls_segment, | |
186 | const elfcpp::Rel<32, false>&, unsigned int r_type, | |
187 | elfcpp::Elf_types<32>::Elf_Addr value, | |
188 | unsigned char* view, | |
189 | off_t view_size); | |
190 | ||
46cf9fa2 ILT |
191 | // We need to keep track of which type of local dynamic relocation |
192 | // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly. | |
193 | enum Local_dynamic_type | |
194 | { | |
195 | LOCAL_DYNAMIC_NONE, | |
196 | LOCAL_DYNAMIC_SUN, | |
197 | LOCAL_DYNAMIC_GNU | |
198 | }; | |
199 | ||
ead1e424 ILT |
200 | // This is set if we should skip the next reloc, which should be a |
201 | // PLT32 reloc against ___tls_get_addr. | |
202 | bool skip_call_tls_get_addr_; | |
46cf9fa2 ILT |
203 | // The type of local dynamic relocation we have seen in the section |
204 | // being relocated, if any. | |
205 | Local_dynamic_type local_dynamic_type_; | |
92e059d8 ILT |
206 | }; |
207 | ||
208 | // Adjust TLS relocation type based on the options and whether this | |
209 | // is a local symbol. | |
af6359d5 | 210 | static tls::Tls_optimization |
7e1edb90 | 211 | optimize_tls_reloc(bool is_final, int r_type); |
92e059d8 | 212 | |
ead1e424 | 213 | // Get the GOT section, creating it if necessary. |
dbe717ef | 214 | Output_data_got<32, false>* |
7e1edb90 | 215 | got_section(Symbol_table*, Layout*); |
a3ad94ed ILT |
216 | |
217 | // Create a PLT entry for a global symbol. | |
218 | void | |
7e1edb90 | 219 | make_plt_entry(Symbol_table*, Layout*, Symbol*); |
a3ad94ed ILT |
220 | |
221 | // Get the PLT section. | |
7bb3655e | 222 | const Output_data_plt_i386* |
a3ad94ed ILT |
223 | plt_section() const |
224 | { | |
225 | gold_assert(this->plt_ != NULL); | |
226 | return this->plt_; | |
227 | } | |
228 | ||
5a6f7e2d ILT |
229 | // Get the dynamic reloc section, creating it if necessary. |
230 | Reloc_section* | |
231 | rel_dyn_section(Layout*); | |
232 | ||
a3ad94ed ILT |
233 | // Copy a relocation against a global symbol. |
234 | void | |
5a6f7e2d ILT |
235 | copy_reloc(const General_options*, Symbol_table*, Layout*, |
236 | Sized_relobj<32, false>*, unsigned int, | |
a3ad94ed | 237 | Symbol*, const elfcpp::Rel<32, false>&); |
ead1e424 | 238 | |
92e059d8 ILT |
239 | // Information about this specific target which we pass to the |
240 | // general Target structure. | |
75f65a3e | 241 | static const Target::Target_info i386_info; |
ead1e424 ILT |
242 | |
243 | // The GOT section. | |
dbe717ef | 244 | Output_data_got<32, false>* got_; |
a3ad94ed ILT |
245 | // The PLT section. |
246 | Output_data_plt_i386* plt_; | |
247 | // The GOT PLT section. | |
248 | Output_data_space* got_plt_; | |
5a6f7e2d ILT |
249 | // The dynamic reloc section. |
250 | Reloc_section* rel_dyn_; | |
251 | // Relocs saved to avoid a COPY reloc. | |
252 | Copy_relocs<32, false>* copy_relocs_; | |
253 | // Space for variables copied with a COPY reloc. | |
254 | Output_data_space* dynbss_; | |
75f65a3e ILT |
255 | }; |
256 | ||
257 | const Target::Target_info Target_i386::i386_info = | |
258 | { | |
61ba1cf9 ILT |
259 | 32, // size |
260 | false, // is_big_endian | |
261 | elfcpp::EM_386, // machine_code | |
262 | false, // has_make_symbol | |
dbe717ef | 263 | false, // has_resolve |
c51e6221 | 264 | true, // has_code_fill |
dbe717ef ILT |
265 | "/usr/lib/libc.so.1", // dynamic_linker |
266 | 0x08048000, // text_segment_address | |
61ba1cf9 ILT |
267 | 0x1000, // abi_pagesize |
268 | 0x1000 // common_pagesize | |
14bfc3f5 ILT |
269 | }; |
270 | ||
ead1e424 ILT |
271 | // Get the GOT section, creating it if necessary. |
272 | ||
dbe717ef | 273 | Output_data_got<32, false>* |
7e1edb90 | 274 | Target_i386::got_section(Symbol_table* symtab, Layout* layout) |
ead1e424 ILT |
275 | { |
276 | if (this->got_ == NULL) | |
277 | { | |
7e1edb90 | 278 | gold_assert(symtab != NULL && layout != NULL); |
a3ad94ed | 279 | |
7e1edb90 | 280 | this->got_ = new Output_data_got<32, false>(); |
ead1e424 | 281 | |
ead1e424 | 282 | layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, |
16649710 ILT |
283 | elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, |
284 | this->got_); | |
ead1e424 | 285 | |
a3ad94ed ILT |
286 | // The old GNU linker creates a .got.plt section. We just |
287 | // create another set of data in the .got section. Note that we | |
288 | // always create a PLT if we create a GOT, although the PLT | |
289 | // might be empty. | |
290 | this->got_plt_ = new Output_data_space(4); | |
291 | layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, | |
16649710 ILT |
292 | elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, |
293 | this->got_plt_); | |
a3ad94ed | 294 | |
ead1e424 | 295 | // The first three entries are reserved. |
a3ad94ed | 296 | this->got_plt_->set_space_size(3 * 4); |
ead1e424 | 297 | |
a3ad94ed | 298 | // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. |
14b31740 | 299 | symtab->define_in_output_data(this, "_GLOBAL_OFFSET_TABLE_", NULL, |
a3ad94ed | 300 | this->got_plt_, |
ead1e424 | 301 | 0, 0, elfcpp::STT_OBJECT, |
16649710 | 302 | elfcpp::STB_LOCAL, |
ead1e424 ILT |
303 | elfcpp::STV_HIDDEN, 0, |
304 | false, false); | |
305 | } | |
a3ad94ed | 306 | |
ead1e424 ILT |
307 | return this->got_; |
308 | } | |
309 | ||
5a6f7e2d ILT |
310 | // Get the dynamic reloc section, creating it if necessary. |
311 | ||
312 | Target_i386::Reloc_section* | |
313 | Target_i386::rel_dyn_section(Layout* layout) | |
314 | { | |
315 | if (this->rel_dyn_ == NULL) | |
316 | { | |
317 | gold_assert(layout != NULL); | |
318 | this->rel_dyn_ = new Reloc_section(); | |
319 | layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL, | |
320 | elfcpp::SHF_ALLOC, this->rel_dyn_); | |
321 | } | |
322 | return this->rel_dyn_; | |
323 | } | |
324 | ||
a3ad94ed ILT |
325 | // A class to handle the PLT data. |
326 | ||
327 | class Output_data_plt_i386 : public Output_section_data | |
328 | { | |
329 | public: | |
330 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section; | |
331 | ||
7e1edb90 | 332 | Output_data_plt_i386(Layout*, Output_data_space*); |
a3ad94ed ILT |
333 | |
334 | // Add an entry to the PLT. | |
335 | void | |
336 | add_entry(Symbol* gsym); | |
337 | ||
16649710 ILT |
338 | // Return the .rel.plt section data. |
339 | const Reloc_section* | |
340 | rel_plt() const | |
341 | { return this->rel_; } | |
342 | ||
343 | protected: | |
344 | void | |
345 | do_adjust_output_section(Output_section* os); | |
346 | ||
a3ad94ed ILT |
347 | private: |
348 | // The size of an entry in the PLT. | |
349 | static const int plt_entry_size = 16; | |
350 | ||
351 | // The first entry in the PLT for an executable. | |
352 | static unsigned char exec_first_plt_entry[plt_entry_size]; | |
353 | ||
354 | // The first entry in the PLT for a shared object. | |
355 | static unsigned char dyn_first_plt_entry[plt_entry_size]; | |
356 | ||
357 | // Other entries in the PLT for an executable. | |
358 | static unsigned char exec_plt_entry[plt_entry_size]; | |
359 | ||
360 | // Other entries in the PLT for a shared object. | |
361 | static unsigned char dyn_plt_entry[plt_entry_size]; | |
362 | ||
363 | // Set the final size. | |
364 | void | |
365 | do_set_address(uint64_t, off_t) | |
366 | { this->set_data_size((this->count_ + 1) * plt_entry_size); } | |
367 | ||
368 | // Write out the PLT data. | |
369 | void | |
370 | do_write(Output_file*); | |
371 | ||
372 | // The reloc section. | |
373 | Reloc_section* rel_; | |
374 | // The .got.plt section. | |
375 | Output_data_space* got_plt_; | |
376 | // The number of PLT entries. | |
377 | unsigned int count_; | |
a3ad94ed ILT |
378 | }; |
379 | ||
380 | // Create the PLT section. The ordinary .got section is an argument, | |
381 | // since we need to refer to the start. We also create our own .got | |
382 | // section just for PLT entries. | |
383 | ||
384 | Output_data_plt_i386::Output_data_plt_i386(Layout* layout, | |
7e1edb90 | 385 | Output_data_space* got_plt) |
80576242 | 386 | : Output_section_data(4), got_plt_(got_plt), count_(0) |
a3ad94ed ILT |
387 | { |
388 | this->rel_ = new Reloc_section(); | |
389 | layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL, | |
390 | elfcpp::SHF_ALLOC, this->rel_); | |
391 | } | |
392 | ||
16649710 ILT |
393 | void |
394 | Output_data_plt_i386::do_adjust_output_section(Output_section* os) | |
395 | { | |
396 | // UnixWare sets the entsize of .plt to 4, and so does the old GNU | |
397 | // linker, and so do we. | |
398 | os->set_entsize(4); | |
399 | } | |
400 | ||
a3ad94ed ILT |
401 | // Add an entry to the PLT. |
402 | ||
403 | void | |
404 | Output_data_plt_i386::add_entry(Symbol* gsym) | |
405 | { | |
406 | gold_assert(!gsym->has_plt_offset()); | |
407 | ||
408 | // Note that when setting the PLT offset we skip the initial | |
409 | // reserved PLT entry. | |
410 | gsym->set_plt_offset((this->count_ + 1) * plt_entry_size); | |
411 | ||
412 | ++this->count_; | |
413 | ||
414 | off_t got_offset = this->got_plt_->data_size(); | |
415 | ||
416 | // Every PLT entry needs a GOT entry which points back to the PLT | |
417 | // entry (this will be changed by the dynamic linker, normally | |
418 | // lazily when the function is called). | |
419 | this->got_plt_->set_space_size(got_offset + 4); | |
420 | ||
421 | // Every PLT entry needs a reloc. | |
16649710 | 422 | gsym->set_needs_dynsym_entry(); |
a3ad94ed ILT |
423 | this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_, |
424 | got_offset); | |
425 | ||
426 | // Note that we don't need to save the symbol. The contents of the | |
427 | // PLT are independent of which symbols are used. The symbols only | |
428 | // appear in the relocations. | |
429 | } | |
430 | ||
431 | // The first entry in the PLT for an executable. | |
432 | ||
433 | unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] = | |
434 | { | |
435 | 0xff, 0x35, // pushl contents of memory address | |
436 | 0, 0, 0, 0, // replaced with address of .got + 4 | |
437 | 0xff, 0x25, // jmp indirect | |
438 | 0, 0, 0, 0, // replaced with address of .got + 8 | |
439 | 0, 0, 0, 0 // unused | |
440 | }; | |
441 | ||
442 | // The first entry in the PLT for a shared object. | |
443 | ||
444 | unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] = | |
445 | { | |
446 | 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx) | |
447 | 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx) | |
448 | 0, 0, 0, 0 // unused | |
449 | }; | |
450 | ||
451 | // Subsequent entries in the PLT for an executable. | |
452 | ||
453 | unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] = | |
454 | { | |
455 | 0xff, 0x25, // jmp indirect | |
456 | 0, 0, 0, 0, // replaced with address of symbol in .got | |
457 | 0x68, // pushl immediate | |
458 | 0, 0, 0, 0, // replaced with offset into relocation table | |
459 | 0xe9, // jmp relative | |
460 | 0, 0, 0, 0 // replaced with offset to start of .plt | |
461 | }; | |
462 | ||
463 | // Subsequent entries in the PLT for a shared object. | |
464 | ||
465 | unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] = | |
466 | { | |
467 | 0xff, 0xa3, // jmp *offset(%ebx) | |
468 | 0, 0, 0, 0, // replaced with offset of symbol in .got | |
469 | 0x68, // pushl immediate | |
470 | 0, 0, 0, 0, // replaced with offset into relocation table | |
471 | 0xe9, // jmp relative | |
472 | 0, 0, 0, 0 // replaced with offset to start of .plt | |
473 | }; | |
474 | ||
475 | // Write out the PLT. This uses the hand-coded instructions above, | |
476 | // and adjusts them as needed. This is all specified by the i386 ELF | |
477 | // Processor Supplement. | |
478 | ||
479 | void | |
480 | Output_data_plt_i386::do_write(Output_file* of) | |
481 | { | |
482 | const off_t offset = this->offset(); | |
483 | const off_t oview_size = this->data_size(); | |
484 | unsigned char* const oview = of->get_output_view(offset, oview_size); | |
485 | ||
486 | const off_t got_file_offset = this->got_plt_->offset(); | |
487 | const off_t got_size = this->got_plt_->data_size(); | |
488 | unsigned char* const got_view = of->get_output_view(got_file_offset, | |
489 | got_size); | |
490 | ||
491 | unsigned char* pov = oview; | |
492 | ||
493 | elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address(); | |
494 | elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address(); | |
495 | ||
7e1edb90 | 496 | if (parameters->output_is_shared()) |
a3ad94ed ILT |
497 | memcpy(pov, dyn_first_plt_entry, plt_entry_size); |
498 | else | |
499 | { | |
500 | memcpy(pov, exec_first_plt_entry, plt_entry_size); | |
501 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4); | |
502 | elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8); | |
503 | } | |
504 | pov += plt_entry_size; | |
505 | ||
506 | unsigned char* got_pov = got_view; | |
507 | ||
508 | memset(got_pov, 0, 12); | |
509 | got_pov += 12; | |
510 | ||
511 | const int rel_size = elfcpp::Elf_sizes<32>::rel_size; | |
512 | ||
513 | unsigned int plt_offset = plt_entry_size; | |
514 | unsigned int plt_rel_offset = 0; | |
515 | unsigned int got_offset = 12; | |
516 | const unsigned int count = this->count_; | |
517 | for (unsigned int i = 0; | |
518 | i < count; | |
519 | ++i, | |
520 | pov += plt_entry_size, | |
521 | got_pov += 4, | |
522 | plt_offset += plt_entry_size, | |
523 | plt_rel_offset += rel_size, | |
524 | got_offset += 4) | |
525 | { | |
526 | // Set and adjust the PLT entry itself. | |
527 | ||
7e1edb90 | 528 | if (parameters->output_is_shared()) |
a3ad94ed ILT |
529 | { |
530 | memcpy(pov, dyn_plt_entry, plt_entry_size); | |
531 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset); | |
532 | } | |
533 | else | |
534 | { | |
535 | memcpy(pov, exec_plt_entry, plt_entry_size); | |
536 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, | |
537 | (got_address | |
538 | + got_offset)); | |
539 | } | |
540 | ||
541 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset); | |
542 | elfcpp::Swap<32, false>::writeval(pov + 12, | |
543 | - (plt_offset + plt_entry_size)); | |
544 | ||
545 | // Set the entry in the GOT. | |
546 | elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6); | |
547 | } | |
548 | ||
549 | gold_assert(pov - oview == oview_size); | |
550 | gold_assert(got_pov - got_view == got_size); | |
551 | ||
552 | of->write_output_view(offset, oview_size, oview); | |
553 | of->write_output_view(got_file_offset, got_size, got_view); | |
554 | } | |
555 | ||
556 | // Create a PLT entry for a global symbol. | |
557 | ||
558 | void | |
7e1edb90 | 559 | Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym) |
a3ad94ed ILT |
560 | { |
561 | if (gsym->has_plt_offset()) | |
562 | return; | |
563 | ||
564 | if (this->plt_ == NULL) | |
565 | { | |
566 | // Create the GOT sections first. | |
7e1edb90 | 567 | this->got_section(symtab, layout); |
a3ad94ed | 568 | |
7e1edb90 | 569 | this->plt_ = new Output_data_plt_i386(layout, this->got_plt_); |
16649710 ILT |
570 | layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS, |
571 | (elfcpp::SHF_ALLOC | |
572 | | elfcpp::SHF_EXECINSTR), | |
573 | this->plt_); | |
a3ad94ed ILT |
574 | } |
575 | ||
576 | this->plt_->add_entry(gsym); | |
577 | } | |
578 | ||
579 | // Handle a relocation against a non-function symbol defined in a | |
580 | // dynamic object. The traditional way to handle this is to generate | |
581 | // a COPY relocation to copy the variable at runtime from the shared | |
582 | // object into the executable's data segment. However, this is | |
583 | // undesirable in general, as if the size of the object changes in the | |
584 | // dynamic object, the executable will no longer work correctly. If | |
585 | // this relocation is in a writable section, then we can create a | |
586 | // dynamic reloc and the dynamic linker will resolve it to the correct | |
587 | // address at runtime. However, we do not want do that if the | |
588 | // relocation is in a read-only section, as it would prevent the | |
589 | // readonly segment from being shared. And if we have to eventually | |
590 | // generate a COPY reloc, then any dynamic relocations will be | |
591 | // useless. So this means that if this is a writable section, we need | |
592 | // to save the relocation until we see whether we have to create a | |
593 | // COPY relocation for this symbol for any other relocation. | |
594 | ||
595 | void | |
596 | Target_i386::copy_reloc(const General_options* options, | |
5a6f7e2d ILT |
597 | Symbol_table* symtab, |
598 | Layout* layout, | |
a3ad94ed ILT |
599 | Sized_relobj<32, false>* object, |
600 | unsigned int data_shndx, Symbol* gsym, | |
5a6f7e2d | 601 | const elfcpp::Rel<32, false>& rel) |
a3ad94ed | 602 | { |
5a6f7e2d ILT |
603 | Sized_symbol<32>* ssym; |
604 | ssym = symtab->get_sized_symbol SELECT_SIZE_NAME(32) (gsym | |
605 | SELECT_SIZE(32)); | |
606 | ||
607 | if (!Copy_relocs<32, false>::need_copy_reloc(options, object, | |
608 | data_shndx, ssym)) | |
a3ad94ed ILT |
609 | { |
610 | // So far we do not need a COPY reloc. Save this relocation. | |
5a6f7e2d ILT |
611 | // If it turns out that we never need a COPY reloc for this |
612 | // symbol, then we will emit the relocation. | |
613 | if (this->copy_relocs_ == NULL) | |
614 | this->copy_relocs_ = new Copy_relocs<32, false>(); | |
615 | this->copy_relocs_->save(ssym, object, data_shndx, rel); | |
a3ad94ed | 616 | } |
5a6f7e2d ILT |
617 | else |
618 | { | |
619 | // Allocate space for this symbol in the .bss section. | |
620 | ||
621 | elfcpp::Elf_types<32>::Elf_WXword symsize = ssym->symsize(); | |
622 | ||
623 | // There is no defined way to determine the required alignment | |
624 | // of the symbol. We pick the alignment based on the size. We | |
625 | // set an arbitrary maximum of 256. | |
626 | unsigned int align; | |
627 | for (align = 1; align < 512; align <<= 1) | |
628 | if ((symsize & align) != 0) | |
629 | break; | |
a3ad94ed | 630 | |
5a6f7e2d ILT |
631 | if (this->dynbss_ == NULL) |
632 | { | |
633 | this->dynbss_ = new Output_data_space(align); | |
634 | layout->add_output_section_data(".bss", | |
635 | elfcpp::SHT_NOBITS, | |
636 | (elfcpp::SHF_ALLOC | |
637 | | elfcpp::SHF_WRITE), | |
638 | this->dynbss_); | |
639 | } | |
640 | ||
641 | Output_data_space* dynbss = this->dynbss_; | |
642 | ||
643 | if (align > dynbss->addralign()) | |
644 | dynbss->set_space_alignment(align); | |
645 | ||
646 | off_t dynbss_size = dynbss->data_size(); | |
647 | dynbss_size = align_address(dynbss_size, align); | |
648 | off_t offset = dynbss_size; | |
649 | dynbss->set_space_size(dynbss_size + symsize); | |
650 | ||
651 | // Define the symbol in the .dynbss section. | |
14b31740 ILT |
652 | symtab->define_in_output_data(this, ssym->name(), ssym->version(), |
653 | dynbss, offset, symsize, ssym->type(), | |
654 | ssym->binding(), ssym->visibility(), | |
655 | ssym->nonvis(), false, false); | |
5a6f7e2d ILT |
656 | |
657 | // Add the COPY reloc. | |
16649710 | 658 | ssym->set_needs_dynsym_entry(); |
5a6f7e2d ILT |
659 | Reloc_section* rel_dyn = this->rel_dyn_section(layout); |
660 | rel_dyn->add_global(ssym, elfcpp::R_386_COPY, dynbss, offset); | |
661 | } | |
a3ad94ed ILT |
662 | } |
663 | ||
92e059d8 | 664 | // Optimize the TLS relocation type based on what we know about the |
a3ad94ed ILT |
665 | // symbol. IS_FINAL is true if the final address of this symbol is |
666 | // known at link time. | |
92e059d8 | 667 | |
af6359d5 | 668 | tls::Tls_optimization |
7e1edb90 | 669 | Target_i386::optimize_tls_reloc(bool is_final, int r_type) |
92e059d8 ILT |
670 | { |
671 | // If we are generating a shared library, then we can't do anything | |
672 | // in the linker. | |
7e1edb90 | 673 | if (parameters->output_is_shared()) |
af6359d5 | 674 | return tls::TLSOPT_NONE; |
92e059d8 ILT |
675 | |
676 | switch (r_type) | |
677 | { | |
678 | case elfcpp::R_386_TLS_GD: | |
679 | case elfcpp::R_386_TLS_GOTDESC: | |
680 | case elfcpp::R_386_TLS_DESC_CALL: | |
681 | // These are Global-Dynamic which permits fully general TLS | |
682 | // access. Since we know that we are generating an executable, | |
683 | // we can convert this to Initial-Exec. If we also know that | |
684 | // this is a local symbol, we can further switch to Local-Exec. | |
a3ad94ed | 685 | if (is_final) |
af6359d5 ILT |
686 | return tls::TLSOPT_TO_LE; |
687 | return tls::TLSOPT_TO_IE; | |
92e059d8 ILT |
688 | |
689 | case elfcpp::R_386_TLS_LDM: | |
690 | // This is Local-Dynamic, which refers to a local symbol in the | |
691 | // dynamic TLS block. Since we know that we generating an | |
692 | // executable, we can switch to Local-Exec. | |
af6359d5 | 693 | return tls::TLSOPT_TO_LE; |
92e059d8 ILT |
694 | |
695 | case elfcpp::R_386_TLS_LDO_32: | |
af6359d5 ILT |
696 | // Another type of Local-Dynamic relocation. |
697 | return tls::TLSOPT_TO_LE; | |
92e059d8 ILT |
698 | |
699 | case elfcpp::R_386_TLS_IE: | |
700 | case elfcpp::R_386_TLS_GOTIE: | |
701 | case elfcpp::R_386_TLS_IE_32: | |
702 | // These are Initial-Exec relocs which get the thread offset | |
703 | // from the GOT. If we know that we are linking against the | |
704 | // local symbol, we can switch to Local-Exec, which links the | |
705 | // thread offset into the instruction. | |
a3ad94ed | 706 | if (is_final) |
af6359d5 ILT |
707 | return tls::TLSOPT_TO_LE; |
708 | return tls::TLSOPT_NONE; | |
8462ae85 | 709 | |
92e059d8 ILT |
710 | case elfcpp::R_386_TLS_LE: |
711 | case elfcpp::R_386_TLS_LE_32: | |
712 | // When we already have Local-Exec, there is nothing further we | |
713 | // can do. | |
af6359d5 | 714 | return tls::TLSOPT_NONE; |
92e059d8 ILT |
715 | |
716 | default: | |
a3ad94ed | 717 | gold_unreachable(); |
92e059d8 ILT |
718 | } |
719 | } | |
720 | ||
af6359d5 ILT |
721 | // Report an unsupported relocation against a local symbol. |
722 | ||
723 | void | |
724 | Target_i386::Scan::unsupported_reloc_local(Sized_relobj<32, false>* object, | |
725 | unsigned int r_type) | |
726 | { | |
727 | fprintf(stderr, _("%s: %s: unsupported reloc %u against local symbol\n"), | |
728 | program_name, object->name().c_str(), r_type); | |
729 | } | |
730 | ||
92e059d8 ILT |
731 | // Scan a relocation for a local symbol. |
732 | ||
733 | inline void | |
7e1edb90 | 734 | Target_i386::Scan::local(const General_options&, |
ead1e424 ILT |
735 | Symbol_table* symtab, |
736 | Layout* layout, | |
737 | Target_i386* target, | |
f6ce93d6 | 738 | Sized_relobj<32, false>* object, |
a3ad94ed ILT |
739 | unsigned int, |
740 | const elfcpp::Rel<32, false>&, | |
741 | unsigned int r_type, | |
92e059d8 ILT |
742 | const elfcpp::Sym<32, false>&) |
743 | { | |
744 | switch (r_type) | |
745 | { | |
746 | case elfcpp::R_386_NONE: | |
747 | case elfcpp::R_386_GNU_VTINHERIT: | |
748 | case elfcpp::R_386_GNU_VTENTRY: | |
749 | break; | |
750 | ||
751 | case elfcpp::R_386_32: | |
752 | case elfcpp::R_386_16: | |
753 | case elfcpp::R_386_8: | |
754 | // FIXME: If we are generating a shared object we need to copy | |
755 | // this relocation into the object. | |
7e1edb90 | 756 | gold_assert(!parameters->output_is_shared()); |
92e059d8 ILT |
757 | break; |
758 | ||
759 | case elfcpp::R_386_PC32: | |
760 | case elfcpp::R_386_PC16: | |
761 | case elfcpp::R_386_PC8: | |
762 | break; | |
763 | ||
ead1e424 ILT |
764 | case elfcpp::R_386_GOTOFF: |
765 | case elfcpp::R_386_GOTPC: | |
766 | // We need a GOT section. | |
7e1edb90 | 767 | target->got_section(symtab, layout); |
ead1e424 ILT |
768 | break; |
769 | ||
af6359d5 ILT |
770 | // These are relocations which should only be seen by the |
771 | // dynamic linker, and should never be seen here. | |
92e059d8 ILT |
772 | case elfcpp::R_386_COPY: |
773 | case elfcpp::R_386_GLOB_DAT: | |
774 | case elfcpp::R_386_JUMP_SLOT: | |
775 | case elfcpp::R_386_RELATIVE: | |
776 | case elfcpp::R_386_TLS_TPOFF: | |
777 | case elfcpp::R_386_TLS_DTPMOD32: | |
778 | case elfcpp::R_386_TLS_DTPOFF32: | |
779 | case elfcpp::R_386_TLS_TPOFF32: | |
780 | case elfcpp::R_386_TLS_DESC: | |
781 | fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), | |
782 | program_name, object->name().c_str(), r_type); | |
783 | gold_exit(false); | |
784 | break; | |
785 | ||
af6359d5 | 786 | // These are initial TLS relocs, which are expected when |
d61c17ea | 787 | // linking. |
92e059d8 ILT |
788 | case elfcpp::R_386_TLS_IE: |
789 | case elfcpp::R_386_TLS_GOTIE: | |
790 | case elfcpp::R_386_TLS_LE: | |
791 | case elfcpp::R_386_TLS_GD: | |
792 | case elfcpp::R_386_TLS_LDM: | |
793 | case elfcpp::R_386_TLS_LDO_32: | |
794 | case elfcpp::R_386_TLS_IE_32: | |
795 | case elfcpp::R_386_TLS_LE_32: | |
796 | case elfcpp::R_386_TLS_GOTDESC: | |
797 | case elfcpp::R_386_TLS_DESC_CALL: | |
7e1edb90 | 798 | { |
80576242 | 799 | bool output_is_shared = parameters->output_is_shared(); |
af6359d5 ILT |
800 | const tls::Tls_optimization optimized_type |
801 | = Target_i386::optimize_tls_reloc(!output_is_shared, r_type); | |
7e1edb90 ILT |
802 | switch (r_type) |
803 | { | |
804 | case elfcpp::R_386_TLS_LE: | |
805 | case elfcpp::R_386_TLS_LE_32: | |
806 | // FIXME: If generating a shared object, we need to copy | |
807 | // this relocation into the object. | |
80576242 | 808 | gold_assert(!output_is_shared); |
7e1edb90 | 809 | break; |
92e059d8 | 810 | |
af6359d5 ILT |
811 | case elfcpp::R_386_TLS_IE: |
812 | case elfcpp::R_386_TLS_IE_32: | |
813 | case elfcpp::R_386_TLS_GOTIE: | |
814 | // FIXME: If not relaxing to LE, we need to generate a | |
815 | // TPOFF or TPOFF32 reloc. | |
816 | if (optimized_type != tls::TLSOPT_TO_LE) | |
817 | unsupported_reloc_local(object, r_type); | |
818 | break; | |
819 | ||
46cf9fa2 | 820 | case elfcpp::R_386_TLS_LDM: |
af6359d5 ILT |
821 | // FIXME: If not relaxing to LE, we need to generate a |
822 | // DTPMOD32 reloc. | |
823 | if (optimized_type != tls::TLSOPT_TO_LE) | |
824 | unsupported_reloc_local(object, r_type); | |
825 | break; | |
826 | ||
46cf9fa2 ILT |
827 | case elfcpp::R_386_TLS_LDO_32: |
828 | break; | |
829 | ||
7e1edb90 | 830 | case elfcpp::R_386_TLS_GD: |
7e1edb90 ILT |
831 | case elfcpp::R_386_TLS_GOTDESC: |
832 | case elfcpp::R_386_TLS_DESC_CALL: | |
af6359d5 ILT |
833 | // FIXME: If not relaxing to LE, we need to generate |
834 | // DTPMOD32 and DTPOFF32 relocs. | |
835 | if (optimized_type != tls::TLSOPT_TO_LE) | |
836 | unsupported_reloc_local(object, r_type); | |
7e1edb90 | 837 | break; |
af6359d5 ILT |
838 | |
839 | default: | |
840 | gold_unreachable(); | |
7e1edb90 ILT |
841 | } |
842 | } | |
92e059d8 ILT |
843 | break; |
844 | ||
845 | case elfcpp::R_386_GOT32: | |
846 | case elfcpp::R_386_PLT32: | |
92e059d8 ILT |
847 | case elfcpp::R_386_32PLT: |
848 | case elfcpp::R_386_TLS_GD_32: | |
849 | case elfcpp::R_386_TLS_GD_PUSH: | |
850 | case elfcpp::R_386_TLS_GD_CALL: | |
851 | case elfcpp::R_386_TLS_GD_POP: | |
852 | case elfcpp::R_386_TLS_LDM_32: | |
853 | case elfcpp::R_386_TLS_LDM_PUSH: | |
854 | case elfcpp::R_386_TLS_LDM_CALL: | |
855 | case elfcpp::R_386_TLS_LDM_POP: | |
856 | case elfcpp::R_386_USED_BY_INTEL_200: | |
857 | default: | |
af6359d5 | 858 | unsupported_reloc_local(object, r_type); |
92e059d8 ILT |
859 | break; |
860 | } | |
861 | } | |
862 | ||
af6359d5 ILT |
863 | // Report an unsupported relocation against a global symbol. |
864 | ||
865 | void | |
866 | Target_i386::Scan::unsupported_reloc_global(Sized_relobj<32, false>* object, | |
867 | unsigned int r_type, | |
868 | Symbol* gsym) | |
869 | { | |
870 | fprintf(stderr, | |
871 | _("%s: %s: unsupported reloc %u against global symbol %s\n"), | |
872 | program_name, object->name().c_str(), r_type, gsym->name()); | |
873 | } | |
874 | ||
92e059d8 ILT |
875 | // Scan a relocation for a global symbol. |
876 | ||
877 | inline void | |
878 | Target_i386::Scan::global(const General_options& options, | |
ead1e424 ILT |
879 | Symbol_table* symtab, |
880 | Layout* layout, | |
881 | Target_i386* target, | |
f6ce93d6 | 882 | Sized_relobj<32, false>* object, |
a3ad94ed ILT |
883 | unsigned int data_shndx, |
884 | const elfcpp::Rel<32, false>& reloc, | |
885 | unsigned int r_type, | |
92e059d8 ILT |
886 | Symbol* gsym) |
887 | { | |
888 | switch (r_type) | |
889 | { | |
890 | case elfcpp::R_386_NONE: | |
891 | case elfcpp::R_386_GNU_VTINHERIT: | |
8462ae85 | 892 | case elfcpp::R_386_GNU_VTENTRY: |
92e059d8 ILT |
893 | break; |
894 | ||
895 | case elfcpp::R_386_32: | |
896 | case elfcpp::R_386_PC32: | |
897 | case elfcpp::R_386_16: | |
898 | case elfcpp::R_386_PC16: | |
899 | case elfcpp::R_386_8: | |
900 | case elfcpp::R_386_PC8: | |
901 | // FIXME: If we are generating a shared object we may need to | |
902 | // copy this relocation into the object. If this symbol is | |
903 | // defined in a shared object, we may need to copy this | |
904 | // relocation in order to avoid a COPY relocation. | |
7e1edb90 | 905 | gold_assert(!parameters->output_is_shared()); |
a3ad94ed | 906 | |
14b31740 | 907 | if (gsym->is_from_dynobj()) |
a3ad94ed ILT |
908 | { |
909 | // This symbol is defined in a dynamic object. If it is a | |
910 | // function, we make a PLT entry. Otherwise we need to | |
911 | // either generate a COPY reloc or copy this reloc. | |
912 | if (gsym->type() == elfcpp::STT_FUNC) | |
ab5c9e90 ILT |
913 | { |
914 | target->make_plt_entry(symtab, layout, gsym); | |
915 | ||
916 | // If this is not a PC relative reference, then we may | |
917 | // be taking the address of the function. In that case | |
918 | // we need to set the entry in the dynamic symbol table | |
919 | // to the address of the PLT entry. | |
920 | if (r_type != elfcpp::R_386_PC32 | |
921 | && r_type != elfcpp::R_386_PC16 | |
922 | && r_type != elfcpp::R_386_PC8) | |
923 | gsym->set_needs_dynsym_value(); | |
924 | } | |
a3ad94ed | 925 | else |
5a6f7e2d ILT |
926 | target->copy_reloc(&options, symtab, layout, object, data_shndx, |
927 | gsym, reloc); | |
a3ad94ed ILT |
928 | } |
929 | ||
92e059d8 ILT |
930 | break; |
931 | ||
ead1e424 | 932 | case elfcpp::R_386_GOT32: |
8462ae85 ILT |
933 | { |
934 | // The symbol requires a GOT entry. | |
7e1edb90 | 935 | Output_data_got<32, false>* got = target->got_section(symtab, layout); |
8462ae85 ILT |
936 | if (got->add_global(gsym)) |
937 | { | |
938 | // If this symbol is not fully resolved, we need to add a | |
939 | // dynamic relocation for it. | |
7e1edb90 | 940 | if (!gsym->final_value_is_known()) |
8462ae85 ILT |
941 | { |
942 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
943 | rel_dyn->add_global(gsym, elfcpp::R_386_GLOB_DAT, got, | |
944 | gsym->got_offset()); | |
945 | } | |
946 | } | |
947 | } | |
ead1e424 ILT |
948 | break; |
949 | ||
950 | case elfcpp::R_386_PLT32: | |
a3ad94ed ILT |
951 | // If the symbol is fully resolved, this is just a PC32 reloc. |
952 | // Otherwise we need a PLT entry. | |
7e1edb90 | 953 | if (gsym->final_value_is_known()) |
ead1e424 | 954 | break; |
7e1edb90 | 955 | target->make_plt_entry(symtab, layout, gsym); |
ead1e424 ILT |
956 | break; |
957 | ||
958 | case elfcpp::R_386_GOTOFF: | |
959 | case elfcpp::R_386_GOTPC: | |
960 | // We need a GOT section. | |
7e1edb90 | 961 | target->got_section(symtab, layout); |
ead1e424 ILT |
962 | break; |
963 | ||
af6359d5 ILT |
964 | // These are relocations which should only be seen by the |
965 | // dynamic linker, and should never be seen here. | |
92e059d8 ILT |
966 | case elfcpp::R_386_COPY: |
967 | case elfcpp::R_386_GLOB_DAT: | |
968 | case elfcpp::R_386_JUMP_SLOT: | |
969 | case elfcpp::R_386_RELATIVE: | |
970 | case elfcpp::R_386_TLS_TPOFF: | |
971 | case elfcpp::R_386_TLS_DTPMOD32: | |
972 | case elfcpp::R_386_TLS_DTPOFF32: | |
973 | case elfcpp::R_386_TLS_TPOFF32: | |
974 | case elfcpp::R_386_TLS_DESC: | |
975 | fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), | |
976 | program_name, object->name().c_str(), r_type); | |
977 | gold_exit(false); | |
978 | break; | |
979 | ||
d61c17ea ILT |
980 | // These are initial tls relocs, which are expected when |
981 | // linking. | |
92e059d8 ILT |
982 | case elfcpp::R_386_TLS_IE: |
983 | case elfcpp::R_386_TLS_GOTIE: | |
984 | case elfcpp::R_386_TLS_LE: | |
985 | case elfcpp::R_386_TLS_GD: | |
986 | case elfcpp::R_386_TLS_LDM: | |
987 | case elfcpp::R_386_TLS_LDO_32: | |
988 | case elfcpp::R_386_TLS_IE_32: | |
989 | case elfcpp::R_386_TLS_LE_32: | |
990 | case elfcpp::R_386_TLS_GOTDESC: | |
991 | case elfcpp::R_386_TLS_DESC_CALL: | |
a3ad94ed | 992 | { |
7e1edb90 | 993 | const bool is_final = gsym->final_value_is_known(); |
af6359d5 ILT |
994 | const tls::Tls_optimization optimized_type |
995 | = Target_i386::optimize_tls_reloc(is_final, r_type); | |
a3ad94ed ILT |
996 | switch (r_type) |
997 | { | |
998 | case elfcpp::R_386_TLS_LE: | |
999 | case elfcpp::R_386_TLS_LE_32: | |
1000 | // FIXME: If generating a shared object, we need to copy | |
1001 | // this relocation into the object. | |
7e1edb90 | 1002 | gold_assert(!parameters->output_is_shared()); |
a3ad94ed ILT |
1003 | break; |
1004 | ||
af6359d5 ILT |
1005 | case elfcpp::R_386_TLS_IE: |
1006 | case elfcpp::R_386_TLS_IE_32: | |
1007 | case elfcpp::R_386_TLS_GOTIE: | |
1008 | // FIXME: If not relaxing to LE, we need to generate a | |
1009 | // TPOFF or TPOFF32 reloc. | |
1010 | if (optimized_type != tls::TLSOPT_TO_LE) | |
1011 | unsupported_reloc_global(object, r_type, gsym); | |
1012 | break; | |
1013 | ||
46cf9fa2 | 1014 | case elfcpp::R_386_TLS_LDM: |
af6359d5 ILT |
1015 | // FIXME: If not relaxing to LE, we need to generate a |
1016 | // DTPMOD32 reloc. | |
1017 | if (optimized_type != tls::TLSOPT_TO_LE) | |
1018 | unsupported_reloc_global(object, r_type, gsym); | |
1019 | break; | |
1020 | ||
46cf9fa2 ILT |
1021 | case elfcpp::R_386_TLS_LDO_32: |
1022 | break; | |
1023 | ||
a3ad94ed | 1024 | case elfcpp::R_386_TLS_GD: |
a3ad94ed ILT |
1025 | case elfcpp::R_386_TLS_GOTDESC: |
1026 | case elfcpp::R_386_TLS_DESC_CALL: | |
af6359d5 ILT |
1027 | // FIXME: If not relaxing to LE, we need to generate |
1028 | // DTPMOD32 and DTPOFF32 relocs. | |
1029 | if (optimized_type != tls::TLSOPT_TO_LE) | |
1030 | unsupported_reloc_global(object, r_type, gsym); | |
a3ad94ed | 1031 | break; |
af6359d5 ILT |
1032 | |
1033 | default: | |
1034 | gold_unreachable(); | |
a3ad94ed ILT |
1035 | } |
1036 | } | |
92e059d8 ILT |
1037 | break; |
1038 | ||
92e059d8 ILT |
1039 | case elfcpp::R_386_32PLT: |
1040 | case elfcpp::R_386_TLS_GD_32: | |
1041 | case elfcpp::R_386_TLS_GD_PUSH: | |
1042 | case elfcpp::R_386_TLS_GD_CALL: | |
1043 | case elfcpp::R_386_TLS_GD_POP: | |
1044 | case elfcpp::R_386_TLS_LDM_32: | |
1045 | case elfcpp::R_386_TLS_LDM_PUSH: | |
1046 | case elfcpp::R_386_TLS_LDM_CALL: | |
1047 | case elfcpp::R_386_TLS_LDM_POP: | |
1048 | case elfcpp::R_386_USED_BY_INTEL_200: | |
1049 | default: | |
af6359d5 | 1050 | unsupported_reloc_global(object, r_type, gsym); |
92e059d8 ILT |
1051 | break; |
1052 | } | |
1053 | } | |
1054 | ||
1055 | // Scan relocations for a section. | |
1056 | ||
1057 | void | |
1058 | Target_i386::scan_relocs(const General_options& options, | |
1059 | Symbol_table* symtab, | |
ead1e424 | 1060 | Layout* layout, |
f6ce93d6 | 1061 | Sized_relobj<32, false>* object, |
a3ad94ed | 1062 | unsigned int data_shndx, |
92e059d8 ILT |
1063 | unsigned int sh_type, |
1064 | const unsigned char* prelocs, | |
1065 | size_t reloc_count, | |
1066 | size_t local_symbol_count, | |
1067 | const unsigned char* plocal_symbols, | |
1068 | Symbol** global_symbols) | |
1069 | { | |
1070 | if (sh_type == elfcpp::SHT_RELA) | |
1071 | { | |
1072 | fprintf(stderr, _("%s: %s: unsupported RELA reloc section\n"), | |
1073 | program_name, object->name().c_str()); | |
1074 | gold_exit(false); | |
1075 | } | |
1076 | ||
ead1e424 ILT |
1077 | gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL, |
1078 | Target_i386::Scan>( | |
92e059d8 ILT |
1079 | options, |
1080 | symtab, | |
ead1e424 ILT |
1081 | layout, |
1082 | this, | |
92e059d8 | 1083 | object, |
a3ad94ed | 1084 | data_shndx, |
92e059d8 ILT |
1085 | prelocs, |
1086 | reloc_count, | |
1087 | local_symbol_count, | |
1088 | plocal_symbols, | |
1089 | global_symbols); | |
1090 | } | |
1091 | ||
16649710 | 1092 | // Finalize the sections. |
5a6f7e2d ILT |
1093 | |
1094 | void | |
7e1edb90 | 1095 | Target_i386::do_finalize_sections(Layout* layout) |
5a6f7e2d | 1096 | { |
16649710 ILT |
1097 | // Fill in some more dynamic tags. |
1098 | Output_data_dynamic* const odyn = layout->dynamic_data(); | |
1099 | if (odyn != NULL) | |
1100 | { | |
1101 | if (this->got_plt_ != NULL) | |
1102 | odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_); | |
1103 | ||
1104 | if (this->plt_ != NULL) | |
1105 | { | |
1106 | const Output_data* od = this->plt_->rel_plt(); | |
1107 | odyn->add_section_size(elfcpp::DT_PLTRELSZ, od); | |
1108 | odyn->add_section_address(elfcpp::DT_JMPREL, od); | |
1109 | odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL); | |
1110 | } | |
1111 | ||
1112 | if (this->rel_dyn_ != NULL) | |
1113 | { | |
1114 | const Output_data* od = this->rel_dyn_; | |
1115 | odyn->add_section_address(elfcpp::DT_REL, od); | |
1116 | odyn->add_section_size(elfcpp::DT_RELSZ, od); | |
1117 | odyn->add_constant(elfcpp::DT_RELENT, | |
1118 | elfcpp::Elf_sizes<32>::rel_size); | |
1119 | } | |
1120 | ||
7e1edb90 | 1121 | if (!parameters->output_is_shared()) |
16649710 ILT |
1122 | { |
1123 | // The value of the DT_DEBUG tag is filled in by the dynamic | |
1124 | // linker at run time, and used by the debugger. | |
1125 | odyn->add_constant(elfcpp::DT_DEBUG, 0); | |
1126 | } | |
1127 | } | |
1128 | ||
1129 | // Emit any relocs we saved in an attempt to avoid generating COPY | |
1130 | // relocs. | |
5a6f7e2d ILT |
1131 | if (this->copy_relocs_ == NULL) |
1132 | return; | |
1133 | if (this->copy_relocs_->any_to_emit()) | |
1134 | { | |
1135 | Reloc_section* rel_dyn = this->rel_dyn_section(layout); | |
1136 | this->copy_relocs_->emit(rel_dyn); | |
1137 | } | |
1138 | delete this->copy_relocs_; | |
1139 | this->copy_relocs_ = NULL; | |
1140 | } | |
1141 | ||
61ba1cf9 ILT |
1142 | // Perform a relocation. |
1143 | ||
ead1e424 | 1144 | inline bool |
92e059d8 | 1145 | Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo, |
ead1e424 | 1146 | Target_i386* target, |
92e059d8 ILT |
1147 | size_t relnum, |
1148 | const elfcpp::Rel<32, false>& rel, | |
1149 | unsigned int r_type, | |
c06b7b0b | 1150 | const Sized_symbol<32>* gsym, |
b8e6aad9 | 1151 | const Symbol_value<32>* psymval, |
92e059d8 ILT |
1152 | unsigned char* view, |
1153 | elfcpp::Elf_types<32>::Elf_Addr address, | |
1154 | off_t view_size) | |
61ba1cf9 | 1155 | { |
ead1e424 ILT |
1156 | if (this->skip_call_tls_get_addr_) |
1157 | { | |
1158 | if (r_type != elfcpp::R_386_PLT32 | |
1159 | || gsym == NULL | |
1160 | || strcmp(gsym->name(), "___tls_get_addr") != 0) | |
1161 | { | |
1162 | fprintf(stderr, _("%s: %s: missing expected TLS relocation\n"), | |
1163 | program_name, | |
1164 | relinfo->location(relnum, rel.get_r_offset()).c_str()); | |
1165 | gold_exit(false); | |
1166 | } | |
1167 | ||
1168 | this->skip_call_tls_get_addr_ = false; | |
1169 | ||
1170 | return false; | |
1171 | } | |
1172 | ||
a3ad94ed | 1173 | // Pick the value to use for symbols defined in shared objects. |
b8e6aad9 | 1174 | Symbol_value<32> symval; |
8462ae85 | 1175 | if (gsym != NULL && gsym->is_from_dynobj() && gsym->has_plt_offset()) |
a3ad94ed | 1176 | { |
b8e6aad9 ILT |
1177 | symval.set_output_value(target->plt_section()->address() |
1178 | + gsym->plt_offset()); | |
1179 | psymval = &symval; | |
a3ad94ed ILT |
1180 | } |
1181 | ||
b8e6aad9 ILT |
1182 | const Sized_relobj<32, false>* object = relinfo->object; |
1183 | ||
61ba1cf9 ILT |
1184 | switch (r_type) |
1185 | { | |
1186 | case elfcpp::R_386_NONE: | |
92e059d8 ILT |
1187 | case elfcpp::R_386_GNU_VTINHERIT: |
1188 | case elfcpp::R_386_GNU_VTENTRY: | |
61ba1cf9 ILT |
1189 | break; |
1190 | ||
1191 | case elfcpp::R_386_32: | |
b8e6aad9 | 1192 | Relocate_functions<32, false>::rel32(view, object, psymval); |
61ba1cf9 ILT |
1193 | break; |
1194 | ||
1195 | case elfcpp::R_386_PC32: | |
b8e6aad9 | 1196 | Relocate_functions<32, false>::pcrel32(view, object, psymval, address); |
92e059d8 ILT |
1197 | break; |
1198 | ||
1199 | case elfcpp::R_386_16: | |
b8e6aad9 | 1200 | Relocate_functions<32, false>::rel16(view, object, psymval); |
92e059d8 ILT |
1201 | break; |
1202 | ||
1203 | case elfcpp::R_386_PC16: | |
b8e6aad9 | 1204 | Relocate_functions<32, false>::pcrel16(view, object, psymval, address); |
61ba1cf9 ILT |
1205 | break; |
1206 | ||
92e059d8 | 1207 | case elfcpp::R_386_8: |
b8e6aad9 | 1208 | Relocate_functions<32, false>::rel8(view, object, psymval); |
92e059d8 ILT |
1209 | break; |
1210 | ||
1211 | case elfcpp::R_386_PC8: | |
b8e6aad9 | 1212 | Relocate_functions<32, false>::pcrel8(view, object, psymval, address); |
92e059d8 ILT |
1213 | break; |
1214 | ||
ead1e424 | 1215 | case elfcpp::R_386_PLT32: |
a3ad94ed | 1216 | gold_assert(gsym->has_plt_offset() |
7e1edb90 | 1217 | || gsym->final_value_is_known()); |
b8e6aad9 | 1218 | Relocate_functions<32, false>::pcrel32(view, object, psymval, address); |
ead1e424 ILT |
1219 | break; |
1220 | ||
1221 | case elfcpp::R_386_GOT32: | |
1222 | // Local GOT offsets not yet supported. | |
a3ad94ed ILT |
1223 | gold_assert(gsym); |
1224 | gold_assert(gsym->has_got_offset()); | |
b8e6aad9 | 1225 | Relocate_functions<32, false>::rel32(view, gsym->got_offset()); |
ead1e424 ILT |
1226 | break; |
1227 | ||
1228 | case elfcpp::R_386_GOTOFF: | |
b8e6aad9 ILT |
1229 | { |
1230 | elfcpp::Elf_types<32>::Elf_Addr value; | |
1231 | value = (psymval->value(object, 0) | |
7e1edb90 | 1232 | - target->got_section(NULL, NULL)->address()); |
b8e6aad9 ILT |
1233 | Relocate_functions<32, false>::rel32(view, value); |
1234 | } | |
ead1e424 ILT |
1235 | break; |
1236 | ||
1237 | case elfcpp::R_386_GOTPC: | |
b8e6aad9 ILT |
1238 | { |
1239 | elfcpp::Elf_types<32>::Elf_Addr value; | |
7e1edb90 | 1240 | value = target->got_section(NULL, NULL)->address(); |
b8e6aad9 ILT |
1241 | Relocate_functions<32, false>::pcrel32(view, value, address); |
1242 | } | |
ead1e424 ILT |
1243 | break; |
1244 | ||
92e059d8 ILT |
1245 | case elfcpp::R_386_COPY: |
1246 | case elfcpp::R_386_GLOB_DAT: | |
1247 | case elfcpp::R_386_JUMP_SLOT: | |
1248 | case elfcpp::R_386_RELATIVE: | |
d61c17ea ILT |
1249 | // These are outstanding tls relocs, which are unexpected when |
1250 | // linking. | |
92e059d8 ILT |
1251 | case elfcpp::R_386_TLS_TPOFF: |
1252 | case elfcpp::R_386_TLS_DTPMOD32: | |
1253 | case elfcpp::R_386_TLS_DTPOFF32: | |
1254 | case elfcpp::R_386_TLS_TPOFF32: | |
1255 | case elfcpp::R_386_TLS_DESC: | |
1256 | fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), | |
1257 | program_name, | |
1258 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1259 | r_type); | |
1260 | gold_exit(false); | |
1261 | break; | |
1262 | ||
d61c17ea ILT |
1263 | // These are initial tls relocs, which are expected when |
1264 | // linking. | |
92e059d8 ILT |
1265 | case elfcpp::R_386_TLS_IE: |
1266 | case elfcpp::R_386_TLS_GOTIE: | |
1267 | case elfcpp::R_386_TLS_LE: | |
1268 | case elfcpp::R_386_TLS_GD: | |
1269 | case elfcpp::R_386_TLS_LDM: | |
1270 | case elfcpp::R_386_TLS_LDO_32: | |
1271 | case elfcpp::R_386_TLS_IE_32: | |
1272 | case elfcpp::R_386_TLS_LE_32: | |
1273 | case elfcpp::R_386_TLS_GOTDESC: | |
1274 | case elfcpp::R_386_TLS_DESC_CALL: | |
b8e6aad9 | 1275 | this->relocate_tls(relinfo, relnum, rel, r_type, gsym, psymval, view, |
ead1e424 | 1276 | address, view_size); |
92e059d8 ILT |
1277 | break; |
1278 | ||
92e059d8 ILT |
1279 | case elfcpp::R_386_32PLT: |
1280 | case elfcpp::R_386_TLS_GD_32: | |
1281 | case elfcpp::R_386_TLS_GD_PUSH: | |
1282 | case elfcpp::R_386_TLS_GD_CALL: | |
1283 | case elfcpp::R_386_TLS_GD_POP: | |
1284 | case elfcpp::R_386_TLS_LDM_32: | |
1285 | case elfcpp::R_386_TLS_LDM_PUSH: | |
1286 | case elfcpp::R_386_TLS_LDM_CALL: | |
1287 | case elfcpp::R_386_TLS_LDM_POP: | |
1288 | case elfcpp::R_386_USED_BY_INTEL_200: | |
61ba1cf9 ILT |
1289 | default: |
1290 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), | |
92e059d8 ILT |
1291 | program_name, |
1292 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1293 | r_type); | |
7d00dcbd | 1294 | gold_exit(false); |
92e059d8 ILT |
1295 | break; |
1296 | } | |
ead1e424 ILT |
1297 | |
1298 | return true; | |
92e059d8 ILT |
1299 | } |
1300 | ||
1301 | // Perform a TLS relocation. | |
1302 | ||
1303 | inline void | |
1304 | Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo, | |
1305 | size_t relnum, | |
1306 | const elfcpp::Rel<32, false>& rel, | |
1307 | unsigned int r_type, | |
c06b7b0b | 1308 | const Sized_symbol<32>* gsym, |
b8e6aad9 | 1309 | const Symbol_value<32>* psymval, |
92e059d8 ILT |
1310 | unsigned char* view, |
1311 | elfcpp::Elf_types<32>::Elf_Addr, | |
1312 | off_t view_size) | |
1313 | { | |
1314 | Output_segment* tls_segment = relinfo->layout->tls_segment(); | |
1315 | if (tls_segment == NULL) | |
1316 | { | |
1317 | fprintf(stderr, _("%s: %s: TLS reloc but no TLS segment\n"), | |
1318 | program_name, | |
1319 | relinfo->location(relnum, rel.get_r_offset()).c_str()); | |
1320 | gold_exit(false); | |
1321 | } | |
1322 | ||
b8e6aad9 ILT |
1323 | elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(relinfo->object, 0); |
1324 | ||
a3ad94ed | 1325 | const bool is_final = (gsym == NULL |
7e1edb90 ILT |
1326 | ? !parameters->output_is_shared() |
1327 | : gsym->final_value_is_known()); | |
af6359d5 ILT |
1328 | const tls::Tls_optimization optimized_type |
1329 | = Target_i386::optimize_tls_reloc(is_final, r_type); | |
92e059d8 ILT |
1330 | switch (r_type) |
1331 | { | |
1332 | case elfcpp::R_386_TLS_LE_32: | |
1333 | value = tls_segment->vaddr() + tls_segment->memsz() - value; | |
1334 | Relocate_functions<32, false>::rel32(view, value); | |
1335 | break; | |
1336 | ||
1337 | case elfcpp::R_386_TLS_LE: | |
1338 | value = value - (tls_segment->vaddr() + tls_segment->memsz()); | |
1339 | Relocate_functions<32, false>::rel32(view, value); | |
1340 | break; | |
1341 | ||
1342 | case elfcpp::R_386_TLS_IE: | |
1343 | case elfcpp::R_386_TLS_GOTIE: | |
1344 | case elfcpp::R_386_TLS_IE_32: | |
af6359d5 | 1345 | if (optimized_type == tls::TLSOPT_TO_LE) |
92e059d8 ILT |
1346 | { |
1347 | Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment, | |
1348 | rel, r_type, value, view, | |
1349 | view_size); | |
1350 | break; | |
1351 | } | |
af6359d5 | 1352 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), |
92e059d8 ILT |
1353 | program_name, |
1354 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1355 | r_type); | |
7d00dcbd | 1356 | gold_exit(false); |
92e059d8 ILT |
1357 | break; |
1358 | ||
1359 | case elfcpp::R_386_TLS_GD: | |
af6359d5 | 1360 | if (optimized_type == tls::TLSOPT_TO_LE) |
ead1e424 ILT |
1361 | { |
1362 | this->tls_gd_to_le(relinfo, relnum, tls_segment, | |
1363 | rel, r_type, value, view, | |
1364 | view_size); | |
1365 | break; | |
1366 | } | |
1367 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), | |
1368 | program_name, | |
1369 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1370 | r_type); | |
7d00dcbd | 1371 | gold_exit(false); |
ead1e424 ILT |
1372 | break; |
1373 | ||
92e059d8 | 1374 | case elfcpp::R_386_TLS_LDM: |
46cf9fa2 ILT |
1375 | if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN) |
1376 | { | |
1377 | fprintf(stderr, | |
1378 | _("%s: %s: both SUN and GNU model TLS relocations\n"), | |
1379 | program_name, | |
1380 | relinfo->location(relnum, rel.get_r_offset()).c_str()); | |
1381 | gold_exit(false); | |
1382 | } | |
1383 | this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU; | |
af6359d5 | 1384 | if (optimized_type == tls::TLSOPT_TO_LE) |
46cf9fa2 ILT |
1385 | { |
1386 | this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type, | |
1387 | value, view, view_size); | |
1388 | break; | |
1389 | } | |
1390 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), | |
1391 | program_name, | |
1392 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1393 | r_type); | |
7d00dcbd | 1394 | gold_exit(false); |
46cf9fa2 ILT |
1395 | break; |
1396 | ||
92e059d8 | 1397 | case elfcpp::R_386_TLS_LDO_32: |
46cf9fa2 ILT |
1398 | // This reloc can appear in debugging sections, in which case we |
1399 | // won't see the TLS_LDM reloc. The local_dynamic_type field | |
1400 | // tells us this. | |
af6359d5 | 1401 | if (optimized_type != tls::TLSOPT_TO_LE |
46cf9fa2 ILT |
1402 | || this->local_dynamic_type_ == LOCAL_DYNAMIC_NONE) |
1403 | value = value - tls_segment->vaddr(); | |
1404 | else if (this->local_dynamic_type_ == LOCAL_DYNAMIC_GNU) | |
1405 | value = value - (tls_segment->vaddr() + tls_segment->memsz()); | |
1406 | else | |
1407 | value = tls_segment->vaddr() + tls_segment->memsz() - value; | |
1408 | Relocate_functions<32, false>::rel32(view, value); | |
1409 | break; | |
1410 | ||
92e059d8 ILT |
1411 | case elfcpp::R_386_TLS_GOTDESC: |
1412 | case elfcpp::R_386_TLS_DESC_CALL: | |
1413 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), | |
1414 | program_name, | |
1415 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1416 | r_type); | |
7d00dcbd | 1417 | gold_exit(false); |
92e059d8 ILT |
1418 | break; |
1419 | } | |
1420 | } | |
1421 | ||
1422 | // Do a relocation in which we convert a TLS Initial-Exec to a | |
1423 | // Local-Exec. | |
1424 | ||
1425 | inline void | |
1426 | Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo, | |
1427 | size_t relnum, | |
1428 | Output_segment* tls_segment, | |
1429 | const elfcpp::Rel<32, false>& rel, | |
1430 | unsigned int r_type, | |
1431 | elfcpp::Elf_types<32>::Elf_Addr value, | |
1432 | unsigned char* view, | |
1433 | off_t view_size) | |
1434 | { | |
1435 | // We have to actually change the instructions, which means that we | |
1436 | // need to examine the opcodes to figure out which instruction we | |
1437 | // are looking at. | |
1438 | if (r_type == elfcpp::R_386_TLS_IE) | |
1439 | { | |
1440 | // movl %gs:XX,%eax ==> movl $YY,%eax | |
1441 | // movl %gs:XX,%reg ==> movl $YY,%reg | |
1442 | // addl %gs:XX,%reg ==> addl $YY,%reg | |
af6359d5 ILT |
1443 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1); |
1444 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4); | |
92e059d8 ILT |
1445 | |
1446 | unsigned char op1 = view[-1]; | |
1447 | if (op1 == 0xa1) | |
1448 | { | |
1449 | // movl XX,%eax ==> movl $YY,%eax | |
1450 | view[-1] = 0xb8; | |
1451 | } | |
1452 | else | |
1453 | { | |
af6359d5 | 1454 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); |
92e059d8 ILT |
1455 | |
1456 | unsigned char op2 = view[-2]; | |
1457 | if (op2 == 0x8b) | |
1458 | { | |
1459 | // movl XX,%reg ==> movl $YY,%reg | |
af6359d5 ILT |
1460 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), |
1461 | (op1 & 0xc7) == 0x05); | |
92e059d8 ILT |
1462 | view[-2] = 0xc7; |
1463 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1464 | } | |
1465 | else if (op2 == 0x03) | |
1466 | { | |
1467 | // addl XX,%reg ==> addl $YY,%reg | |
af6359d5 ILT |
1468 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), |
1469 | (op1 & 0xc7) == 0x05); | |
92e059d8 ILT |
1470 | view[-2] = 0x81; |
1471 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1472 | } | |
1473 | else | |
af6359d5 | 1474 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0); |
92e059d8 ILT |
1475 | } |
1476 | } | |
1477 | else | |
1478 | { | |
1479 | // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2 | |
1480 | // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2 | |
1481 | // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2 | |
af6359d5 ILT |
1482 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); |
1483 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4); | |
92e059d8 ILT |
1484 | |
1485 | unsigned char op1 = view[-1]; | |
1486 | unsigned char op2 = view[-2]; | |
af6359d5 ILT |
1487 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), |
1488 | (op1 & 0xc0) == 0x80 && (op1 & 7) != 4); | |
92e059d8 ILT |
1489 | if (op2 == 0x8b) |
1490 | { | |
1491 | // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2 | |
1492 | view[-2] = 0xc7; | |
1493 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1494 | } | |
1495 | else if (op2 == 0x2b) | |
1496 | { | |
1497 | // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2 | |
1498 | view[-2] = 0x81; | |
1499 | view[-1] = 0xe8 | ((op1 >> 3) & 7); | |
1500 | } | |
1501 | else if (op2 == 0x03) | |
1502 | { | |
1503 | // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2 | |
1504 | view[-2] = 0x81; | |
1505 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1506 | } | |
1507 | else | |
af6359d5 | 1508 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0); |
92e059d8 ILT |
1509 | } |
1510 | ||
ead1e424 ILT |
1511 | value = tls_segment->vaddr() + tls_segment->memsz() - value; |
1512 | if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE) | |
1513 | value = - value; | |
92e059d8 ILT |
1514 | |
1515 | Relocate_functions<32, false>::rel32(view, value); | |
1516 | } | |
1517 | ||
ead1e424 ILT |
1518 | // Do a relocation in which we convert a TLS Global-Dynamic to a |
1519 | // Local-Exec. | |
1520 | ||
1521 | inline void | |
1522 | Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo, | |
1523 | size_t relnum, | |
1524 | Output_segment* tls_segment, | |
1525 | const elfcpp::Rel<32, false>& rel, | |
1526 | unsigned int, | |
1527 | elfcpp::Elf_types<32>::Elf_Addr value, | |
1528 | unsigned char* view, | |
1529 | off_t view_size) | |
1530 | { | |
1531 | // leal foo(,%reg,1),%eax; call ___tls_get_addr | |
46cf9fa2 | 1532 | // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax |
ead1e424 ILT |
1533 | // leal foo(%reg),%eax; call ___tls_get_addr |
1534 | // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax | |
1535 | ||
af6359d5 ILT |
1536 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); |
1537 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9); | |
ead1e424 ILT |
1538 | |
1539 | unsigned char op1 = view[-1]; | |
1540 | unsigned char op2 = view[-2]; | |
1541 | ||
af6359d5 ILT |
1542 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), |
1543 | op2 == 0x8d || op2 == 0x04); | |
1544 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8); | |
ead1e424 ILT |
1545 | |
1546 | int roff = 5; | |
1547 | ||
1548 | if (op2 == 0x04) | |
1549 | { | |
af6359d5 ILT |
1550 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3); |
1551 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d); | |
1552 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), | |
1553 | ((op1 & 0xc7) == 0x05 && op1 != (4 << 3))); | |
ead1e424 ILT |
1554 | memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); |
1555 | } | |
1556 | else | |
1557 | { | |
af6359d5 ILT |
1558 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), |
1559 | (op1 & 0xf8) == 0x80 && (op1 & 7) != 4); | |
d61c17ea ILT |
1560 | if (static_cast<off_t>(rel.get_r_offset() + 9) < view_size |
1561 | && view[9] == 0x90) | |
ead1e424 ILT |
1562 | { |
1563 | // There is a trailing nop. Use the size byte subl. | |
1564 | memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); | |
1565 | roff = 6; | |
1566 | } | |
1567 | else | |
1568 | { | |
1569 | // Use the five byte subl. | |
1570 | memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11); | |
1571 | } | |
1572 | } | |
1573 | ||
1574 | value = tls_segment->vaddr() + tls_segment->memsz() - value; | |
1575 | Relocate_functions<32, false>::rel32(view + roff, value); | |
1576 | ||
1577 | // The next reloc should be a PLT32 reloc against __tls_get_addr. | |
1578 | // We can skip it. | |
1579 | this->skip_call_tls_get_addr_ = true; | |
1580 | } | |
1581 | ||
46cf9fa2 ILT |
1582 | // Do a relocation in which we convert a TLS Local-Dynamic to a |
1583 | // Local-Exec. | |
1584 | ||
1585 | inline void | |
1586 | Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo, | |
1587 | size_t relnum, | |
1588 | Output_segment*, | |
1589 | const elfcpp::Rel<32, false>& rel, | |
1590 | unsigned int, | |
1591 | elfcpp::Elf_types<32>::Elf_Addr, | |
1592 | unsigned char* view, | |
1593 | off_t view_size) | |
1594 | { | |
1595 | // leal foo(%reg), %eax; call ___tls_get_addr | |
1596 | // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi | |
1597 | ||
af6359d5 ILT |
1598 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); |
1599 | tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9); | |
46cf9fa2 ILT |
1600 | |
1601 | // FIXME: Does this test really always pass? | |
af6359d5 ILT |
1602 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), |
1603 | view[-2] == 0x8d && view[-1] == 0x83); | |
46cf9fa2 | 1604 | |
af6359d5 | 1605 | tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8); |
46cf9fa2 ILT |
1606 | |
1607 | memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11); | |
1608 | ||
1609 | // The next reloc should be a PLT32 reloc against __tls_get_addr. | |
1610 | // We can skip it. | |
1611 | this->skip_call_tls_get_addr_ = true; | |
1612 | } | |
1613 | ||
61ba1cf9 ILT |
1614 | // Relocate section data. |
1615 | ||
1616 | void | |
92e059d8 | 1617 | Target_i386::relocate_section(const Relocate_info<32, false>* relinfo, |
61ba1cf9 ILT |
1618 | unsigned int sh_type, |
1619 | const unsigned char* prelocs, | |
1620 | size_t reloc_count, | |
61ba1cf9 ILT |
1621 | unsigned char* view, |
1622 | elfcpp::Elf_types<32>::Elf_Addr address, | |
1623 | off_t view_size) | |
1624 | { | |
a3ad94ed | 1625 | gold_assert(sh_type == elfcpp::SHT_REL); |
61ba1cf9 | 1626 | |
ead1e424 ILT |
1627 | gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL, |
1628 | Target_i386::Relocate>( | |
92e059d8 | 1629 | relinfo, |
ead1e424 | 1630 | this, |
61ba1cf9 ILT |
1631 | prelocs, |
1632 | reloc_count, | |
61ba1cf9 ILT |
1633 | view, |
1634 | address, | |
1635 | view_size); | |
1636 | } | |
1637 | ||
ab5c9e90 ILT |
1638 | // Return the value to use for a dynamic which requires special |
1639 | // treatment. This is how we support equality comparisons of function | |
1640 | // pointers across shared library boundaries, as described in the | |
1641 | // processor specific ABI supplement. | |
1642 | ||
1643 | uint64_t | |
1644 | Target_i386::do_dynsym_value(const Symbol* gsym) const | |
1645 | { | |
1646 | gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset()); | |
1647 | return this->plt_section()->address() + gsym->plt_offset(); | |
1648 | } | |
1649 | ||
c51e6221 ILT |
1650 | // Return a string used to fill a code section with nops to take up |
1651 | // the specified length. | |
1652 | ||
1653 | std::string | |
1654 | Target_i386::do_code_fill(off_t length) | |
1655 | { | |
1656 | if (length >= 16) | |
1657 | { | |
1658 | // Build a jmp instruction to skip over the bytes. | |
1659 | unsigned char jmp[5]; | |
1660 | jmp[0] = 0xe9; | |
1661 | elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5); | |
1662 | return (std::string(reinterpret_cast<char*>(&jmp[0]), 5) | |
1663 | + std::string(length - 5, '\0')); | |
1664 | } | |
1665 | ||
1666 | // Nop sequences of various lengths. | |
1667 | const char nop1[1] = { 0x90 }; // nop | |
1668 | const char nop2[2] = { 0x66, 0x90 }; // xchg %ax %ax | |
1669 | const char nop3[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi | |
1670 | const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi | |
1671 | const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26, // nop | |
1672 | 0x00 }; // leal 0(%esi,1),%esi | |
1673 | const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi | |
1674 | 0x00, 0x00 }; | |
1675 | const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi | |
1676 | 0x00, 0x00, 0x00 }; | |
1677 | const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop | |
1678 | 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi | |
1679 | const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi | |
1680 | 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi | |
1681 | 0x00 }; | |
1682 | const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi | |
1683 | 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi | |
1684 | 0x00, 0x00 }; | |
1685 | const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi | |
1686 | 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi | |
1687 | 0x00, 0x00, 0x00 }; | |
1688 | const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi | |
1689 | 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi | |
1690 | 0x00, 0x00, 0x00, 0x00 }; | |
1691 | const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi | |
1692 | 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi | |
1693 | 0x27, 0x00, 0x00, 0x00, | |
1694 | 0x00 }; | |
1695 | const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi | |
1696 | 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi | |
1697 | 0xbc, 0x27, 0x00, 0x00, | |
1698 | 0x00, 0x00 }; | |
1699 | const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15 | |
1700 | 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,... | |
1701 | 0x90, 0x90, 0x90, 0x90, | |
1702 | 0x90, 0x90, 0x90 }; | |
1703 | ||
1704 | const char* nops[16] = { | |
1705 | NULL, | |
1706 | nop1, nop2, nop3, nop4, nop5, nop6, nop7, | |
1707 | nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15 | |
1708 | }; | |
1709 | ||
1710 | return std::string(nops[length], length); | |
1711 | } | |
1712 | ||
14bfc3f5 ILT |
1713 | // The selector for i386 object files. |
1714 | ||
1715 | class Target_selector_i386 : public Target_selector | |
1716 | { | |
1717 | public: | |
1718 | Target_selector_i386() | |
1719 | : Target_selector(elfcpp::EM_386, 32, false) | |
1720 | { } | |
1721 | ||
1722 | Target* | |
ead1e424 ILT |
1723 | recognize(int machine, int osabi, int abiversion); |
1724 | ||
1725 | private: | |
1726 | Target_i386* target_; | |
14bfc3f5 ILT |
1727 | }; |
1728 | ||
1729 | // Recognize an i386 object file when we already know that the machine | |
1730 | // number is EM_386. | |
1731 | ||
1732 | Target* | |
ead1e424 | 1733 | Target_selector_i386::recognize(int, int, int) |
14bfc3f5 | 1734 | { |
ead1e424 ILT |
1735 | if (this->target_ == NULL) |
1736 | this->target_ = new Target_i386(); | |
1737 | return this->target_; | |
14bfc3f5 ILT |
1738 | } |
1739 | ||
1740 | Target_selector_i386 target_selector_i386; | |
1741 | ||
1742 | } // End anonymous namespace. |