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2e30d253 ILT |
1 | // x86_64.cc -- x86_64 target support for gold. |
2 | ||
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 | |
9 | // modify it under the terms of the GNU Library General Public License | |
10 | // as published by the Free Software Foundation; either version 2, or | |
11 | // (at your option) any later version. | |
12 | ||
13 | // In addition to the permissions in the GNU Library General Public | |
14 | // License, the Free Software Foundation gives you unlimited | |
15 | // permission to link the compiled version of this file into | |
16 | // combinations with other programs, and to distribute those | |
17 | // combinations without any restriction coming from the use of this | |
18 | // file. (The Library Public License restrictions do apply in other | |
19 | // respects; for example, they cover modification of the file, and | |
20 | /// distribution when not linked into a combined executable.) | |
21 | ||
22 | // This program is distributed in the hope that it will be useful, but | |
23 | // WITHOUT ANY WARRANTY; without even the implied warranty of | |
24 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
25 | // Library General Public License for more details. | |
26 | ||
27 | // You should have received a copy of the GNU Library General Public | |
28 | // License along with this program; if not, write to the Free Software | |
29 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA | |
30 | // 02110-1301, USA. | |
31 | ||
32 | #include "gold.h" | |
33 | ||
34 | #include <cstring> | |
35 | ||
36 | #include "elfcpp.h" | |
37 | #include "parameters.h" | |
38 | #include "reloc.h" | |
39 | #include "x86_64.h" | |
40 | #include "object.h" | |
41 | #include "symtab.h" | |
42 | #include "layout.h" | |
43 | #include "output.h" | |
44 | #include "target.h" | |
45 | #include "target-reloc.h" | |
46 | #include "target-select.h" | |
47 | ||
48 | namespace | |
49 | { | |
50 | ||
51 | using namespace gold; | |
52 | ||
53 | class Output_data_plt_x86_64; | |
54 | ||
55 | // The x86_64 target class. | |
56 | // See the ABI at http://www.x86-64.org/documentation/abi.pdf | |
57 | ||
58 | class Target_x86_64 : public Sized_target<64, false> | |
59 | { | |
60 | public: | |
e822f2b1 ILT |
61 | // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures |
62 | // uses only Elf64_Rela relocation entries with explicit addends." | |
2e30d253 ILT |
63 | typedef Output_data_reloc<elfcpp::SHT_RELA, true, 64, false> Reloc_section; |
64 | ||
65 | Target_x86_64() | |
66 | : Sized_target<64, false>(&x86_64_info), | |
67 | got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), | |
68 | copy_relocs_(NULL), dynbss_(NULL) | |
69 | { } | |
70 | ||
71 | // Scan the relocations to look for symbol adjustments. | |
72 | void | |
73 | scan_relocs(const General_options& options, | |
74 | Symbol_table* symtab, | |
75 | Layout* layout, | |
76 | Sized_relobj<64, false>* object, | |
77 | unsigned int data_shndx, | |
78 | unsigned int sh_type, | |
79 | const unsigned char* prelocs, | |
80 | size_t reloc_count, | |
81 | size_t local_symbol_count, | |
82 | const unsigned char* plocal_symbols, | |
83 | Symbol** global_symbols); | |
84 | ||
85 | // Finalize the sections. | |
86 | void | |
87 | do_finalize_sections(Layout*); | |
88 | ||
4fb6c25d ILT |
89 | // Return the value to use for a dynamic which requires special |
90 | // treatment. | |
91 | uint64_t | |
92 | do_dynsym_value(const Symbol*) const; | |
93 | ||
2e30d253 ILT |
94 | // Relocate a section. |
95 | void | |
96 | relocate_section(const Relocate_info<64, false>*, | |
97 | unsigned int sh_type, | |
98 | const unsigned char* prelocs, | |
99 | size_t reloc_count, | |
100 | unsigned char* view, | |
101 | elfcpp::Elf_types<64>::Elf_Addr view_address, | |
102 | off_t view_size); | |
103 | ||
104 | // Return a string used to fill a code section with nops. | |
105 | std::string | |
106 | do_code_fill(off_t length); | |
107 | ||
108 | private: | |
109 | // The class which scans relocations. | |
110 | struct Scan | |
111 | { | |
112 | inline void | |
113 | local(const General_options& options, Symbol_table* symtab, | |
114 | Layout* layout, Target_x86_64* target, | |
115 | Sized_relobj<64, false>* object, | |
116 | unsigned int data_shndx, | |
117 | const elfcpp::Rela<64, false>& reloc, unsigned int r_type, | |
118 | const elfcpp::Sym<64, false>& lsym); | |
119 | ||
120 | inline void | |
121 | global(const General_options& options, Symbol_table* symtab, | |
122 | Layout* layout, Target_x86_64* target, | |
123 | Sized_relobj<64, false>* object, | |
124 | unsigned int data_shndx, | |
125 | const elfcpp::Rela<64, false>& reloc, unsigned int r_type, | |
126 | Symbol* gsym); | |
127 | }; | |
128 | ||
129 | // The class which implements relocation. | |
130 | class Relocate | |
131 | { | |
132 | public: | |
133 | Relocate() | |
134 | : skip_call_tls_get_addr_(false) | |
135 | { } | |
136 | ||
137 | ~Relocate() | |
138 | { | |
139 | if (this->skip_call_tls_get_addr_) | |
140 | { | |
141 | // FIXME: This needs to specify the location somehow. | |
142 | fprintf(stderr, _("%s: missing expected TLS relocation\n"), | |
143 | program_name); | |
144 | gold_exit(false); | |
145 | } | |
146 | } | |
147 | ||
148 | // Do a relocation. Return false if the caller should not issue | |
149 | // any warnings about this relocation. | |
150 | inline bool | |
151 | relocate(const Relocate_info<64, false>*, Target_x86_64*, size_t relnum, | |
152 | const elfcpp::Rela<64, false>&, | |
153 | unsigned int r_type, const Sized_symbol<64>*, | |
154 | const Symbol_value<64>*, | |
155 | unsigned char*, elfcpp::Elf_types<64>::Elf_Addr, | |
156 | off_t); | |
157 | ||
158 | private: | |
159 | // Do a TLS relocation. | |
160 | inline void | |
161 | relocate_tls(const Relocate_info<64, false>*, size_t relnum, | |
162 | const elfcpp::Rela<64, false>&, | |
163 | unsigned int r_type, const Sized_symbol<64>*, | |
164 | const Symbol_value<64>*, | |
165 | unsigned char*, elfcpp::Elf_types<64>::Elf_Addr, off_t); | |
166 | ||
167 | // Do a TLS Initial-Exec to Local-Exec transition. | |
168 | static inline void | |
169 | tls_ie_to_le(const Relocate_info<64, false>*, size_t relnum, | |
170 | Output_segment* tls_segment, | |
171 | const elfcpp::Rela<64, false>&, unsigned int r_type, | |
172 | elfcpp::Elf_types<64>::Elf_Addr value, | |
173 | unsigned char* view, | |
174 | off_t view_size); | |
175 | ||
176 | // Do a TLS Global-Dynamic to Local-Exec transition. | |
177 | inline void | |
178 | tls_gd_to_le(const Relocate_info<64, false>*, size_t relnum, | |
179 | Output_segment* tls_segment, | |
180 | const elfcpp::Rela<64, false>&, unsigned int r_type, | |
181 | elfcpp::Elf_types<64>::Elf_Addr value, | |
182 | unsigned char* view, | |
183 | off_t view_size); | |
184 | ||
185 | // Check the range for a TLS relocation. | |
186 | static inline void | |
187 | check_range(const Relocate_info<64, false>*, size_t relnum, | |
188 | const elfcpp::Rela<64, false>&, off_t, off_t); | |
189 | ||
190 | // Check the validity of a TLS relocation. This is like assert. | |
191 | static inline void | |
192 | check_tls(const Relocate_info<64, false>*, size_t relnum, | |
193 | const elfcpp::Rela<64, false>&, bool); | |
194 | ||
195 | // This is set if we should skip the next reloc, which should be a | |
196 | // PLT32 reloc against ___tls_get_addr. | |
197 | bool skip_call_tls_get_addr_; | |
198 | }; | |
199 | ||
200 | // Adjust TLS relocation type based on the options and whether this | |
201 | // is a local symbol. | |
202 | static unsigned int | |
203 | optimize_tls_reloc(bool is_final, int r_type); | |
204 | ||
205 | // Get the GOT section, creating it if necessary. | |
206 | Output_data_got<64, false>* | |
207 | got_section(Symbol_table*, Layout*); | |
208 | ||
209 | // Create a PLT entry for a global symbol. | |
210 | void | |
211 | make_plt_entry(Symbol_table*, Layout*, Symbol*); | |
212 | ||
213 | // Get the PLT section. | |
214 | Output_data_plt_x86_64* | |
215 | plt_section() const | |
216 | { | |
217 | gold_assert(this->plt_ != NULL); | |
218 | return this->plt_; | |
219 | } | |
220 | ||
221 | // Get the dynamic reloc section, creating it if necessary. | |
222 | Reloc_section* | |
223 | rel_dyn_section(Layout*); | |
224 | ||
225 | // Copy a relocation against a global symbol. | |
226 | void | |
227 | copy_reloc(const General_options*, Symbol_table*, Layout*, | |
228 | Sized_relobj<64, false>*, unsigned int, | |
229 | Symbol*, const elfcpp::Rela<64, false>&); | |
230 | ||
231 | // Information about this specific target which we pass to the | |
232 | // general Target structure. | |
233 | static const Target::Target_info x86_64_info; | |
234 | ||
235 | // The GOT section. | |
236 | Output_data_got<64, false>* got_; | |
237 | // The PLT section. | |
238 | Output_data_plt_x86_64* plt_; | |
239 | // The GOT PLT section. | |
240 | Output_data_space* got_plt_; | |
241 | // The dynamic reloc section. | |
242 | Reloc_section* rel_dyn_; | |
243 | // Relocs saved to avoid a COPY reloc. | |
244 | Copy_relocs<64, false>* copy_relocs_; | |
245 | // Space for variables copied with a COPY reloc. | |
246 | Output_data_space* dynbss_; | |
247 | }; | |
248 | ||
249 | const Target::Target_info Target_x86_64::x86_64_info = | |
250 | { | |
251 | 64, // size | |
252 | false, // is_big_endian | |
253 | elfcpp::EM_X86_64, // machine_code | |
254 | false, // has_make_symbol | |
255 | false, // has_resolve | |
256 | true, // has_code_fill | |
257 | "/lib/ld64.so.1", // program interpreter | |
258 | 0x400000, // text_segment_address | |
259 | 0x1000, // abi_pagesize | |
260 | 0x1000 // common_pagesize | |
261 | }; | |
262 | ||
263 | // Get the GOT section, creating it if necessary. | |
264 | ||
265 | Output_data_got<64, false>* | |
266 | Target_x86_64::got_section(Symbol_table* symtab, Layout* layout) | |
267 | { | |
268 | if (this->got_ == NULL) | |
269 | { | |
270 | gold_assert(symtab != NULL && layout != NULL); | |
271 | ||
272 | this->got_ = new Output_data_got<64, false>(); | |
273 | ||
274 | layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, | |
275 | elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, | |
276 | this->got_); | |
277 | ||
278 | // The old GNU linker creates a .got.plt section. We just | |
279 | // create another set of data in the .got section. Note that we | |
280 | // always create a PLT if we create a GOT, although the PLT | |
281 | // might be empty. | |
282 | // TODO(csilvers): do we really need an alignment of 8? | |
283 | this->got_plt_ = new Output_data_space(8); | |
284 | layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, | |
285 | elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, | |
286 | this->got_plt_); | |
287 | ||
288 | // The first three entries are reserved. | |
289 | this->got_plt_->set_space_size(3 * 8); | |
290 | ||
291 | // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. | |
292 | symtab->define_in_output_data(this, "_GLOBAL_OFFSET_TABLE_", NULL, | |
293 | this->got_plt_, | |
294 | 0, 0, elfcpp::STT_OBJECT, | |
295 | elfcpp::STB_LOCAL, | |
296 | elfcpp::STV_HIDDEN, 0, | |
297 | false, false); | |
298 | } | |
299 | ||
300 | return this->got_; | |
301 | } | |
302 | ||
303 | // Get the dynamic reloc section, creating it if necessary. | |
304 | ||
305 | Target_x86_64::Reloc_section* | |
306 | Target_x86_64::rel_dyn_section(Layout* layout) | |
307 | { | |
308 | if (this->rel_dyn_ == NULL) | |
309 | { | |
310 | gold_assert(layout != NULL); | |
311 | this->rel_dyn_ = new Reloc_section(); | |
312 | layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA, | |
313 | elfcpp::SHF_ALLOC, this->rel_dyn_); | |
314 | } | |
315 | return this->rel_dyn_; | |
316 | } | |
317 | ||
318 | // A class to handle the PLT data. | |
319 | ||
320 | class Output_data_plt_x86_64 : public Output_section_data | |
321 | { | |
322 | public: | |
323 | typedef Output_data_reloc<elfcpp::SHT_RELA, true, 64, false> Reloc_section; | |
324 | ||
325 | Output_data_plt_x86_64(Layout*, Output_data_space*); | |
326 | ||
327 | // Add an entry to the PLT. | |
328 | void | |
329 | add_entry(Symbol* gsym); | |
330 | ||
331 | // Return the .rel.plt section data. | |
332 | const Reloc_section* | |
333 | rel_plt() const | |
334 | { return this->rel_; } | |
335 | ||
336 | protected: | |
337 | void | |
338 | do_adjust_output_section(Output_section* os); | |
339 | ||
340 | private: | |
341 | // The size of an entry in the PLT. | |
342 | static const int plt_entry_size = 16; | |
343 | ||
344 | // The first entry in the PLT. | |
345 | // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same | |
346 | // procedure linkage table for both programs and shared objects." | |
347 | static unsigned char first_plt_entry[plt_entry_size]; | |
348 | ||
349 | // Other entries in the PLT for an executable. | |
350 | static unsigned char plt_entry[plt_entry_size]; | |
351 | ||
352 | // Set the final size. | |
353 | void | |
354 | do_set_address(uint64_t, off_t) | |
355 | { this->set_data_size((this->count_ + 1) * plt_entry_size); } | |
356 | ||
357 | // Write out the PLT data. | |
358 | void | |
359 | do_write(Output_file*); | |
360 | ||
361 | // The reloc section. | |
362 | Reloc_section* rel_; | |
363 | // The .got.plt section. | |
364 | Output_data_space* got_plt_; | |
365 | // The number of PLT entries. | |
366 | unsigned int count_; | |
367 | }; | |
368 | ||
369 | // Create the PLT section. The ordinary .got section is an argument, | |
370 | // since we need to refer to the start. We also create our own .got | |
371 | // section just for PLT entries. | |
372 | ||
373 | Output_data_plt_x86_64::Output_data_plt_x86_64(Layout* layout, | |
374 | Output_data_space* got_plt) | |
375 | // TODO(csilvers): do we really need an alignment of 8? | |
376 | : Output_section_data(8), got_plt_(got_plt), count_(0) | |
377 | { | |
378 | this->rel_ = new Reloc_section(); | |
379 | layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA, | |
380 | elfcpp::SHF_ALLOC, this->rel_); | |
381 | } | |
382 | ||
383 | void | |
384 | Output_data_plt_x86_64::do_adjust_output_section(Output_section* os) | |
385 | { | |
386 | // UnixWare sets the entsize of .plt to 4, and so does the old GNU | |
387 | // linker, and so do we. | |
388 | os->set_entsize(4); | |
389 | } | |
390 | ||
391 | // Add an entry to the PLT. | |
392 | ||
393 | void | |
394 | Output_data_plt_x86_64::add_entry(Symbol* gsym) | |
395 | { | |
396 | gold_assert(!gsym->has_plt_offset()); | |
397 | ||
398 | // Note that when setting the PLT offset we skip the initial | |
399 | // reserved PLT entry. | |
400 | gsym->set_plt_offset((this->count_ + 1) * plt_entry_size); | |
401 | ||
402 | ++this->count_; | |
403 | ||
404 | off_t got_offset = this->got_plt_->data_size(); | |
405 | ||
406 | // Every PLT entry needs a GOT entry which points back to the PLT | |
407 | // entry (this will be changed by the dynamic linker, normally | |
408 | // lazily when the function is called). | |
409 | this->got_plt_->set_space_size(got_offset + 8); | |
410 | ||
411 | // Every PLT entry needs a reloc. | |
412 | gsym->set_needs_dynsym_entry(); | |
413 | this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_, | |
414 | got_offset, 0); | |
415 | ||
416 | // Note that we don't need to save the symbol. The contents of the | |
417 | // PLT are independent of which symbols are used. The symbols only | |
418 | // appear in the relocations. | |
419 | } | |
420 | ||
421 | // The first entry in the PLT for an executable. | |
422 | ||
423 | unsigned char Output_data_plt_x86_64::first_plt_entry[plt_entry_size] = | |
424 | { | |
425 | // From AMD64 ABI Draft 0.98, page 76 | |
426 | 0xff, 0x35, // pushq contents of memory address | |
427 | 0, 0, 0, 0, // replaced with address of .got + 4 | |
428 | 0xff, 0x25, // jmp indirect | |
429 | 0, 0, 0, 0, // replaced with address of .got + 8 | |
430 | 0x90, 0x90, 0x90, 0x90 // noop (x4) | |
431 | }; | |
432 | ||
433 | // Subsequent entries in the PLT for an executable. | |
434 | ||
435 | unsigned char Output_data_plt_x86_64::plt_entry[plt_entry_size] = | |
436 | { | |
437 | // From AMD64 ABI Draft 0.98, page 76 | |
438 | 0xff, 0x25, // jmpq indirect | |
439 | 0, 0, 0, 0, // replaced with address of symbol in .got | |
440 | 0x68, // pushq immediate | |
441 | 0, 0, 0, 0, // replaced with offset into relocation table | |
442 | 0xe9, // jmpq relative | |
443 | 0, 0, 0, 0 // replaced with offset to start of .plt | |
444 | }; | |
445 | ||
446 | // Write out the PLT. This uses the hand-coded instructions above, | |
447 | // and adjusts them as needed. This is specified by the AMD64 ABI. | |
448 | ||
449 | void | |
450 | Output_data_plt_x86_64::do_write(Output_file* of) | |
451 | { | |
452 | const off_t offset = this->offset(); | |
453 | const off_t oview_size = this->data_size(); | |
454 | unsigned char* const oview = of->get_output_view(offset, oview_size); | |
455 | ||
456 | const off_t got_file_offset = this->got_plt_->offset(); | |
457 | const off_t got_size = this->got_plt_->data_size(); | |
458 | unsigned char* const got_view = of->get_output_view(got_file_offset, | |
459 | got_size); | |
460 | ||
461 | unsigned char* pov = oview; | |
462 | ||
463 | elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address(); | |
464 | elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address(); | |
465 | ||
466 | memcpy(pov, first_plt_entry, plt_entry_size); | |
467 | if (!parameters->output_is_shared()) | |
468 | { | |
469 | // We do a jmp relative to the PC at the end of this instruction. | |
470 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 8 | |
471 | - (plt_address + 6)); | |
472 | elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 16 | |
473 | - (plt_address + 12)); | |
474 | } | |
475 | pov += plt_entry_size; | |
476 | ||
477 | unsigned char* got_pov = got_view; | |
478 | ||
479 | memset(got_pov, 0, 24); | |
480 | got_pov += 24; | |
481 | ||
482 | unsigned int plt_offset = plt_entry_size; | |
483 | unsigned int got_offset = 24; | |
484 | const unsigned int count = this->count_; | |
485 | for (unsigned int plt_index = 0; | |
486 | plt_index < count; | |
487 | ++plt_index, | |
488 | pov += plt_entry_size, | |
489 | got_pov += 8, | |
490 | plt_offset += plt_entry_size, | |
491 | got_offset += 8) | |
492 | { | |
493 | // Set and adjust the PLT entry itself. | |
494 | memcpy(pov, plt_entry, plt_entry_size); | |
495 | if (parameters->output_is_shared()) | |
496 | // FIXME(csilvers): what's the right thing to write here? | |
497 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset); | |
498 | else | |
499 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, | |
500 | (got_address + got_offset | |
501 | - (plt_address + plt_offset | |
502 | + 6))); | |
503 | ||
504 | elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index); | |
505 | elfcpp::Swap<32, false>::writeval(pov + 12, | |
506 | - (plt_offset + plt_entry_size)); | |
507 | ||
508 | // Set the entry in the GOT. | |
509 | elfcpp::Swap<64, false>::writeval(got_pov, plt_address + plt_offset + 6); | |
510 | } | |
511 | ||
512 | gold_assert(pov - oview == oview_size); | |
513 | gold_assert(got_pov - got_view == got_size); | |
514 | ||
515 | of->write_output_view(offset, oview_size, oview); | |
516 | of->write_output_view(got_file_offset, got_size, got_view); | |
517 | } | |
518 | ||
519 | // Create a PLT entry for a global symbol. | |
520 | ||
521 | void | |
522 | Target_x86_64::make_plt_entry(Symbol_table* symtab, Layout* layout, | |
523 | Symbol* gsym) | |
524 | { | |
525 | if (gsym->has_plt_offset()) | |
526 | return; | |
527 | ||
528 | if (this->plt_ == NULL) | |
529 | { | |
530 | // Create the GOT sections first. | |
531 | this->got_section(symtab, layout); | |
532 | ||
533 | this->plt_ = new Output_data_plt_x86_64(layout, this->got_plt_); | |
534 | layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS, | |
535 | (elfcpp::SHF_ALLOC | |
536 | | elfcpp::SHF_EXECINSTR), | |
537 | this->plt_); | |
538 | } | |
539 | ||
540 | this->plt_->add_entry(gsym); | |
541 | } | |
542 | ||
543 | // Handle a relocation against a non-function symbol defined in a | |
544 | // dynamic object. The traditional way to handle this is to generate | |
545 | // a COPY relocation to copy the variable at runtime from the shared | |
546 | // object into the executable's data segment. However, this is | |
547 | // undesirable in general, as if the size of the object changes in the | |
548 | // dynamic object, the executable will no longer work correctly. If | |
549 | // this relocation is in a writable section, then we can create a | |
550 | // dynamic reloc and the dynamic linker will resolve it to the correct | |
551 | // address at runtime. However, we do not want do that if the | |
552 | // relocation is in a read-only section, as it would prevent the | |
553 | // readonly segment from being shared. And if we have to eventually | |
554 | // generate a COPY reloc, then any dynamic relocations will be | |
555 | // useless. So this means that if this is a writable section, we need | |
556 | // to save the relocation until we see whether we have to create a | |
557 | // COPY relocation for this symbol for any other relocation. | |
558 | ||
559 | void | |
560 | Target_x86_64::copy_reloc(const General_options* options, | |
561 | Symbol_table* symtab, | |
562 | Layout* layout, | |
563 | Sized_relobj<64, false>* object, | |
564 | unsigned int data_shndx, Symbol* gsym, | |
565 | const elfcpp::Rela<64, false>& rel) | |
566 | { | |
567 | Sized_symbol<64>* ssym; | |
568 | ssym = symtab->get_sized_symbol SELECT_SIZE_NAME(64) (gsym | |
569 | SELECT_SIZE(64)); | |
570 | ||
571 | if (!Copy_relocs<64, false>::need_copy_reloc(options, object, | |
572 | data_shndx, ssym)) | |
573 | { | |
574 | // So far we do not need a COPY reloc. Save this relocation. | |
575 | // If it turns out that we never need a COPY reloc for this | |
576 | // symbol, then we will emit the relocation. | |
577 | if (this->copy_relocs_ == NULL) | |
578 | this->copy_relocs_ = new Copy_relocs<64, false>(); | |
579 | this->copy_relocs_->save(ssym, object, data_shndx, rel); | |
580 | } | |
581 | else | |
582 | { | |
583 | // Allocate space for this symbol in the .bss section. | |
584 | ||
585 | elfcpp::Elf_types<64>::Elf_WXword symsize = ssym->symsize(); | |
586 | ||
587 | // There is no defined way to determine the required alignment | |
588 | // of the symbol. We pick the alignment based on the size. We | |
589 | // set an arbitrary maximum of 256. | |
590 | unsigned int align; | |
591 | for (align = 1; align < 512; align <<= 1) | |
592 | if ((symsize & align) != 0) | |
593 | break; | |
594 | ||
595 | if (this->dynbss_ == NULL) | |
596 | { | |
597 | this->dynbss_ = new Output_data_space(align); | |
598 | layout->add_output_section_data(".bss", | |
599 | elfcpp::SHT_NOBITS, | |
600 | (elfcpp::SHF_ALLOC | |
601 | | elfcpp::SHF_WRITE), | |
602 | this->dynbss_); | |
603 | } | |
604 | ||
605 | Output_data_space* dynbss = this->dynbss_; | |
606 | ||
607 | if (align > dynbss->addralign()) | |
608 | dynbss->set_space_alignment(align); | |
609 | ||
610 | off_t dynbss_size = dynbss->data_size(); | |
611 | dynbss_size = align_address(dynbss_size, align); | |
612 | off_t offset = dynbss_size; | |
613 | dynbss->set_space_size(dynbss_size + symsize); | |
614 | ||
615 | // Define the symbol in the .dynbss section. | |
616 | symtab->define_in_output_data(this, ssym->name(), ssym->version(), | |
617 | dynbss, offset, symsize, ssym->type(), | |
618 | ssym->binding(), ssym->visibility(), | |
619 | ssym->nonvis(), false, false); | |
620 | ||
621 | // Add the COPY reloc. | |
622 | ssym->set_needs_dynsym_entry(); | |
623 | Reloc_section* rel_dyn = this->rel_dyn_section(layout); | |
624 | rel_dyn->add_global(ssym, elfcpp::R_X86_64_COPY, dynbss, offset, | |
625 | rel.get_r_addend()); | |
626 | } | |
627 | } | |
628 | ||
629 | ||
630 | // Optimize the TLS relocation type based on what we know about the | |
631 | // symbol. IS_FINAL is true if the final address of this symbol is | |
632 | // known at link time. | |
633 | ||
634 | unsigned int | |
635 | Target_x86_64::optimize_tls_reloc(bool is_final, int r_type) | |
636 | { | |
637 | return is_final ? r_type : 0; | |
638 | #if 0 | |
639 | // If we are generating a shared library, then we can't do anything | |
640 | // in the linker. | |
641 | if (parameters->output_is_shared()) | |
642 | return r_type; | |
643 | ||
644 | switch (r_type) | |
645 | { | |
646 | case elfcpp::R_X86_64_TLSGD: | |
647 | // These are Global-Dynamic which permits fully general TLS | |
648 | // access. Since we know that we are generating an executable, | |
649 | // we can convert this to Initial-Exec. If we also know that | |
650 | // this is a local symbol, we can further switch to Local-Exec. | |
651 | if (is_final) | |
652 | return elfcpp::R_X86_64_TLS_LE_64; | |
653 | return elfcpp::R_X86_64_TLS_IE_64; | |
654 | ||
655 | case elfcpp::R_X86_64_TLS_LDM: | |
656 | // This is Local-Dynamic, which refers to a local symbol in the | |
657 | // dynamic TLS block. Since we know that we generating an | |
658 | // executable, we can switch to Local-Exec. | |
659 | return elfcpp::R_X86_64_TLS_LE_64; | |
660 | ||
661 | case elfcpp::R_X86_64_TLS_LDO_64: | |
662 | // Another type of Local-Dynamic relocation. | |
663 | return elfcpp::R_X86_64_TLS_LE; | |
664 | ||
665 | case elfcpp::R_X86_64_TLS_IE: | |
666 | case elfcpp::R_X86_64_TLS_GOTIE: | |
667 | case elfcpp::R_X86_64_TLS_IE_64: | |
668 | // These are Initial-Exec relocs which get the thread offset | |
669 | // from the GOT. If we know that we are linking against the | |
670 | // local symbol, we can switch to Local-Exec, which links the | |
671 | // thread offset into the instruction. | |
672 | if (is_final) | |
673 | return elfcpp::R_X86_64_TLS_LE_64; | |
674 | return r_type; | |
675 | ||
676 | case elfcpp::R_X86_64_TLS_LE: | |
677 | case elfcpp::R_X86_64_TLS_LE_64: | |
678 | // When we already have Local-Exec, there is nothing further we | |
679 | // can do. | |
680 | return r_type; | |
681 | ||
682 | default: | |
683 | gold_unreachable(); | |
684 | } | |
685 | #endif | |
686 | } | |
687 | ||
688 | // Scan a relocation for a local symbol. | |
689 | ||
690 | inline void | |
691 | Target_x86_64::Scan::local(const General_options&, | |
692 | Symbol_table* symtab, | |
693 | Layout* layout, | |
694 | Target_x86_64* target, | |
695 | Sized_relobj<64, false>* object, | |
696 | unsigned int, | |
697 | const elfcpp::Rela<64, false>&, | |
698 | unsigned int r_type, | |
699 | const elfcpp::Sym<64, false>&) | |
700 | { | |
701 | switch (r_type) | |
702 | { | |
703 | case elfcpp::R_X86_64_NONE: | |
e822f2b1 ILT |
704 | case elfcpp::R_386_GNU_VTINHERIT: |
705 | case elfcpp::R_386_GNU_VTENTRY: | |
2e30d253 ILT |
706 | break; |
707 | ||
708 | case elfcpp::R_X86_64_64: | |
709 | case elfcpp::R_X86_64_32: | |
710 | case elfcpp::R_X86_64_32S: | |
711 | case elfcpp::R_X86_64_16: | |
712 | case elfcpp::R_X86_64_8: | |
713 | // FIXME: If we are generating a shared object we need to copy | |
714 | // this relocation into the object. | |
715 | gold_assert(!parameters->output_is_shared()); | |
716 | break; | |
717 | ||
718 | case elfcpp::R_X86_64_PC64: | |
719 | case elfcpp::R_X86_64_PC32: | |
720 | case elfcpp::R_X86_64_PC16: | |
721 | case elfcpp::R_X86_64_PC8: | |
722 | break; | |
723 | ||
2e30d253 | 724 | case elfcpp::R_X86_64_GOTPCREL: |
e822f2b1 ILT |
725 | case elfcpp::R_X86_64_GOTPC32: // TODO(csilvers): correct? |
726 | case elfcpp::R_X86_64_GOT64: // TODO(csilvers): correct? | |
727 | case elfcpp::R_X86_64_GOTOFF64: | |
728 | case elfcpp::R_X86_64_GOTPC64: // TODO(csilvers): correct? | |
729 | case elfcpp::R_X86_64_GOTPCREL64: // TODO(csilvers): correct? | |
730 | case elfcpp::R_X86_64_GOTPLT64: // TODO(csilvers): correct? | |
731 | case elfcpp::R_X86_64_PLTOFF64: // TODO(csilvers): correct? | |
2e30d253 ILT |
732 | // We need a GOT section. |
733 | target->got_section(symtab, layout); | |
734 | break; | |
735 | ||
736 | case elfcpp::R_X86_64_COPY: | |
737 | case elfcpp::R_X86_64_GLOB_DAT: | |
738 | case elfcpp::R_X86_64_JUMP_SLOT: | |
739 | case elfcpp::R_X86_64_RELATIVE: | |
740 | case elfcpp::R_X86_64_TPOFF64: | |
741 | case elfcpp::R_X86_64_TPOFF32: | |
742 | case elfcpp::R_X86_64_DTPMOD64: | |
743 | case elfcpp::R_X86_64_DTPOFF64: | |
744 | case elfcpp::R_X86_64_DTPOFF32: | |
e822f2b1 | 745 | case elfcpp::R_X86_64_GOTTPOFF: // TODO(csilvers): correct? |
2e30d253 | 746 | case elfcpp::R_X86_64_TLSDESC: |
e822f2b1 ILT |
747 | case elfcpp::R_X86_64_GOTPC32_TLSDESC: // TODO(csilvers): correct? |
748 | case elfcpp::R_X86_64_TLSDESC_CALL: // TODO(csilvers): correct? | |
2e30d253 ILT |
749 | fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), |
750 | program_name, object->name().c_str(), r_type); | |
751 | gold_exit(false); | |
752 | break; | |
753 | ||
754 | #if 0 | |
e822f2b1 ILT |
755 | case elfcpp::R_X86_64_TLSGD: // TODO(csilvers): correct? |
756 | case elfcpp::R_X86_64_TLSLD: // TODO(csilvers): correct? | |
757 | ||
758 | case elfcpp::R_386_TLS_IE: | |
759 | case elfcpp::R_386_TLS_GOTIE: | |
760 | case elfcpp::R_386_TLS_LE: | |
761 | case elfcpp::R_386_TLS_GD: | |
762 | case elfcpp::R_386_TLS_LDM: | |
763 | case elfcpp::R_386_TLS_LDO_64: | |
764 | case elfcpp::R_386_TLS_IE_64: | |
765 | case elfcpp::R_386_TLS_LE_64: | |
2e30d253 ILT |
766 | { |
767 | bool output_is_shared = parameters->output_is_shared(); | |
768 | r_type = Target_x86_64::optimize_tls_reloc(!output_is_shared, | |
769 | r_type); | |
770 | switch (r_type) | |
771 | { | |
772 | case elfcpp::R_X86_64_TLS_LE: | |
773 | case elfcpp::R_X86_64_TLS_LE_64: | |
774 | // FIXME: If generating a shared object, we need to copy | |
775 | // this relocation into the object. | |
776 | gold_assert(!output_is_shared); | |
777 | break; | |
778 | ||
779 | case elfcpp::R_X86_64_TLS_IE: | |
780 | case elfcpp::R_X86_64_TLS_GOTIE: | |
781 | case elfcpp::R_X86_64_TLS_GD: | |
782 | case elfcpp::R_X86_64_TLS_LDM: | |
783 | case elfcpp::R_X86_64_TLS_LDO_64: | |
784 | case elfcpp::R_X86_64_TLS_IE_64: | |
785 | fprintf(stderr, | |
786 | _("%s: %s: unsupported reloc %u against local symbol\n"), | |
787 | program_name, object->name().c_str(), r_type); | |
788 | break; | |
789 | } | |
790 | } | |
791 | break; | |
792 | #endif | |
793 | ||
2e30d253 ILT |
794 | case elfcpp::R_X86_64_GOT32: |
795 | case elfcpp::R_X86_64_PLT32: | |
e822f2b1 ILT |
796 | case elfcpp::R_X86_64_SIZE32: // TODO(csilvers): correct? |
797 | case elfcpp::R_X86_64_SIZE64: // TODO(csilvers): correct? | |
798 | #if 0 | |
799 | case elfcpp::R_386_TLS_GD_64: | |
800 | case elfcpp::R_386_TLS_GD_PUSH: | |
801 | case elfcpp::R_386_TLS_GD_CALL: | |
802 | case elfcpp::R_386_TLS_GD_POP: | |
803 | case elfcpp::R_386_TLS_LDM_64: | |
804 | case elfcpp::R_386_TLS_LDM_PUSH: | |
805 | case elfcpp::R_386_TLS_LDM_CALL: | |
806 | case elfcpp::R_386_TLS_LDM_POP: | |
2e30d253 ILT |
807 | #endif |
808 | default: | |
809 | fprintf(stderr, _("%s: %s: unsupported reloc %u against local symbol\n"), | |
810 | program_name, object->name().c_str(), r_type); | |
811 | break; | |
812 | } | |
813 | } | |
814 | ||
815 | ||
816 | // Scan a relocation for a global symbol. | |
817 | ||
818 | inline void | |
819 | Target_x86_64::Scan::global(const General_options& options, | |
820 | Symbol_table* symtab, | |
821 | Layout* layout, | |
822 | Target_x86_64* target, | |
823 | Sized_relobj<64, false>* object, | |
824 | unsigned int data_shndx, | |
825 | const elfcpp::Rela<64, false>& reloc, | |
826 | unsigned int r_type, | |
827 | Symbol* gsym) | |
828 | { | |
829 | switch (r_type) | |
830 | { | |
831 | case elfcpp::R_X86_64_NONE: | |
e822f2b1 ILT |
832 | case elfcpp::R_386_GNU_VTINHERIT: |
833 | case elfcpp::R_386_GNU_VTENTRY: | |
2e30d253 ILT |
834 | break; |
835 | ||
836 | case elfcpp::R_X86_64_64: | |
837 | case elfcpp::R_X86_64_PC64: | |
838 | case elfcpp::R_X86_64_32: | |
839 | case elfcpp::R_X86_64_32S: | |
840 | case elfcpp::R_X86_64_PC32: | |
841 | case elfcpp::R_X86_64_16: | |
842 | case elfcpp::R_X86_64_PC16: | |
843 | case elfcpp::R_X86_64_8: | |
844 | case elfcpp::R_X86_64_PC8: | |
845 | // FIXME: If we are generating a shared object we may need to | |
846 | // copy this relocation into the object. If this symbol is | |
847 | // defined in a shared object, we may need to copy this | |
848 | // relocation in order to avoid a COPY relocation. | |
849 | gold_assert(!parameters->output_is_shared()); | |
850 | ||
851 | if (gsym->is_from_dynobj()) | |
852 | { | |
853 | // This symbol is defined in a dynamic object. If it is a | |
854 | // function, we make a PLT entry. Otherwise we need to | |
855 | // either generate a COPY reloc or copy this reloc. | |
856 | if (gsym->type() == elfcpp::STT_FUNC) | |
4fb6c25d ILT |
857 | { |
858 | target->make_plt_entry(symtab, layout, gsym); | |
859 | ||
860 | // If this is not a PC relative reference, then we may | |
861 | // be taking the address of the function. In that case | |
862 | // we need to set the entry in the dynamic symbol table | |
863 | // to the address of the PLT entry. | |
864 | if (r_type != elfcpp::R_X86_64_PC64 | |
865 | && r_type != elfcpp::R_X86_64_PC32 | |
866 | && r_type != elfcpp::R_X86_64_PC16 | |
867 | && r_type != elfcpp::R_X86_64_PC8) | |
868 | gsym->set_needs_dynsym_value(); | |
869 | } | |
2e30d253 ILT |
870 | else |
871 | target->copy_reloc(&options, symtab, layout, object, data_shndx, | |
872 | gsym, reloc); | |
873 | } | |
874 | ||
875 | break; | |
876 | ||
877 | case elfcpp::R_X86_64_GOT32: | |
878 | { | |
879 | // The symbol requires a GOT entry. | |
880 | Output_data_got<64, false>* got = target->got_section(symtab, layout); | |
881 | if (got->add_global(gsym)) | |
882 | { | |
883 | // If this symbol is not fully resolved, we need to add a | |
884 | // dynamic relocation for it. | |
885 | if (!gsym->final_value_is_known()) | |
886 | { | |
887 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
888 | rel_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT, got, | |
889 | gsym->got_offset(), reloc.get_r_addend()); | |
890 | } | |
891 | } | |
892 | } | |
893 | break; | |
894 | ||
895 | case elfcpp::R_X86_64_PLT32: | |
896 | // If the symbol is fully resolved, this is just a PC32 reloc. | |
897 | // Otherwise we need a PLT entry. | |
898 | if (gsym->final_value_is_known()) | |
899 | break; | |
900 | target->make_plt_entry(symtab, layout, gsym); | |
901 | break; | |
902 | ||
2e30d253 | 903 | case elfcpp::R_X86_64_GOTPCREL: |
e822f2b1 ILT |
904 | case elfcpp::R_X86_64_GOTPC32: // TODO(csilvers): correct? |
905 | case elfcpp::R_X86_64_GOT64: // TODO(csilvers): correct? | |
906 | case elfcpp::R_X86_64_GOTOFF64: | |
907 | case elfcpp::R_X86_64_GOTPC64: // TODO(csilvers): correct? | |
908 | case elfcpp::R_X86_64_GOTPCREL64: // TODO(csilvers): correct? | |
909 | case elfcpp::R_X86_64_GOTPLT64: // TODO(csilvers): correct? | |
910 | case elfcpp::R_X86_64_PLTOFF64: // TODO(csilvers): correct? | |
2e30d253 ILT |
911 | // We need a GOT section. |
912 | target->got_section(symtab, layout); | |
913 | break; | |
914 | ||
2e30d253 ILT |
915 | case elfcpp::R_X86_64_COPY: |
916 | case elfcpp::R_X86_64_GLOB_DAT: | |
917 | case elfcpp::R_X86_64_JUMP_SLOT: | |
918 | case elfcpp::R_X86_64_RELATIVE: | |
e822f2b1 ILT |
919 | case elfcpp::R_X86_64_TPOFF64: |
920 | case elfcpp::R_X86_64_TPOFF32: | |
2e30d253 ILT |
921 | case elfcpp::R_X86_64_DTPMOD64: |
922 | case elfcpp::R_X86_64_DTPOFF64: | |
923 | case elfcpp::R_X86_64_DTPOFF32: | |
e822f2b1 ILT |
924 | case elfcpp::R_X86_64_GOTTPOFF: // TODO(csilvers): correct? |
925 | case elfcpp::R_X86_64_TLSDESC: | |
926 | case elfcpp::R_X86_64_GOTPC32_TLSDESC: // TODO(csilvers): correct? | |
927 | case elfcpp::R_X86_64_TLSDESC_CALL: // TODO(csilvers): correct? | |
2e30d253 ILT |
928 | fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), |
929 | program_name, object->name().c_str(), r_type); | |
930 | gold_exit(false); | |
931 | break; | |
2e30d253 ILT |
932 | |
933 | #if 0 | |
e822f2b1 ILT |
934 | case elfcpp::R_X86_64_TLSGD: // TODO(csilvers): correct? |
935 | case elfcpp::R_X86_64_TLSLD: // TODO(csilvers): correct? | |
936 | ||
937 | case elfcpp::R_386_TLS_IE: | |
938 | case elfcpp::R_386_TLS_GOTIE: | |
939 | case elfcpp::R_386_TLS_LE: | |
940 | case elfcpp::R_386_TLS_GD: | |
941 | case elfcpp::R_386_TLS_LDM: | |
942 | case elfcpp::R_386_TLS_LDO_64: | |
943 | case elfcpp::R_386_TLS_IE_64: | |
944 | case elfcpp::R_386_TLS_LE_64: | |
2e30d253 ILT |
945 | { |
946 | const bool is_final = gsym->final_value_is_known(); | |
947 | r_type = Target_x86_64::optimize_tls_reloc(is_final, r_type); | |
948 | switch (r_type) | |
949 | { | |
e822f2b1 ILT |
950 | case elfcpp::R_386_TLS_LE: |
951 | case elfcpp::R_386_TLS_LE_64: | |
2e30d253 ILT |
952 | // FIXME: If generating a shared object, we need to copy |
953 | // this relocation into the object. | |
954 | gold_assert(!parameters->output_is_shared()); | |
955 | break; | |
956 | ||
e822f2b1 ILT |
957 | case elfcpp::R_386_TLS_IE: |
958 | case elfcpp::R_386_TLS_GOTIE: | |
959 | case elfcpp::R_386_TLS_GD: | |
960 | case elfcpp::R_386_TLS_LDM: | |
961 | case elfcpp::R_386_TLS_LDO_64: | |
962 | case elfcpp::R_386_TLS_IE_64: | |
2e30d253 ILT |
963 | fprintf(stderr, |
964 | _("%s: %s: unsupported reloc %u " | |
965 | "against global symbol %s\n"), | |
966 | program_name, object->name().c_str(), r_type, | |
967 | gsym->name()); | |
968 | break; | |
969 | } | |
970 | } | |
971 | break; | |
972 | #endif | |
973 | ||
e822f2b1 ILT |
974 | case elfcpp::R_X86_64_SIZE32: // TODO(csilvers): correct? |
975 | case elfcpp::R_X86_64_SIZE64: // TODO(csilvers): correct? | |
2e30d253 | 976 | #if 0 |
e822f2b1 ILT |
977 | case elfcpp::R_386_TLS_GD_64: |
978 | case elfcpp::R_386_TLS_GD_PUSH: | |
979 | case elfcpp::R_386_TLS_GD_CALL: | |
980 | case elfcpp::R_386_TLS_GD_POP: | |
981 | case elfcpp::R_386_TLS_LDM_64: | |
982 | case elfcpp::R_386_TLS_LDM_PUSH: | |
983 | case elfcpp::R_386_TLS_LDM_CALL: | |
984 | case elfcpp::R_386_TLS_LDM_POP: | |
2e30d253 ILT |
985 | #endif |
986 | default: | |
987 | fprintf(stderr, | |
988 | _("%s: %s: unsupported reloc %u against global symbol %s\n"), | |
989 | program_name, object->name().c_str(), r_type, gsym->name()); | |
990 | break; | |
991 | } | |
992 | } | |
993 | ||
994 | // Scan relocations for a section. | |
995 | ||
996 | void | |
997 | Target_x86_64::scan_relocs(const General_options& options, | |
998 | Symbol_table* symtab, | |
999 | Layout* layout, | |
1000 | Sized_relobj<64, false>* object, | |
1001 | unsigned int data_shndx, | |
1002 | unsigned int sh_type, | |
1003 | const unsigned char* prelocs, | |
1004 | size_t reloc_count, | |
1005 | size_t local_symbol_count, | |
1006 | const unsigned char* plocal_symbols, | |
1007 | Symbol** global_symbols) | |
1008 | { | |
1009 | if (sh_type == elfcpp::SHT_REL) | |
1010 | { | |
1011 | fprintf(stderr, _("%s: %s: unsupported REL reloc section\n"), | |
1012 | program_name, object->name().c_str()); | |
1013 | gold_exit(false); | |
1014 | } | |
1015 | ||
1016 | gold::scan_relocs<64, false, Target_x86_64, elfcpp::SHT_RELA, | |
1017 | Target_x86_64::Scan>( | |
1018 | options, | |
1019 | symtab, | |
1020 | layout, | |
1021 | this, | |
1022 | object, | |
1023 | data_shndx, | |
1024 | prelocs, | |
1025 | reloc_count, | |
1026 | local_symbol_count, | |
1027 | plocal_symbols, | |
1028 | global_symbols); | |
1029 | } | |
1030 | ||
1031 | // Finalize the sections. | |
1032 | ||
1033 | void | |
1034 | Target_x86_64::do_finalize_sections(Layout* layout) | |
1035 | { | |
1036 | // Fill in some more dynamic tags. | |
1037 | Output_data_dynamic* const odyn = layout->dynamic_data(); | |
1038 | if (odyn != NULL) | |
1039 | { | |
1040 | if (this->got_plt_ != NULL) | |
1041 | odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_); | |
1042 | ||
1043 | if (this->plt_ != NULL) | |
1044 | { | |
1045 | const Output_data* od = this->plt_->rel_plt(); | |
1046 | odyn->add_section_size(elfcpp::DT_PLTRELSZ, od); | |
1047 | odyn->add_section_address(elfcpp::DT_JMPREL, od); | |
1048 | odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_RELA); | |
1049 | } | |
1050 | ||
1051 | if (this->rel_dyn_ != NULL) | |
1052 | { | |
1053 | const Output_data* od = this->rel_dyn_; | |
1054 | odyn->add_section_address(elfcpp::DT_RELA, od); | |
e84992bb | 1055 | odyn->add_section_size(elfcpp::DT_RELASZ, od); |
2e30d253 | 1056 | odyn->add_constant(elfcpp::DT_RELAENT, |
e84992bb | 1057 | elfcpp::Elf_sizes<64>::rela_size); |
2e30d253 ILT |
1058 | } |
1059 | ||
1060 | if (!parameters->output_is_shared()) | |
1061 | { | |
1062 | // The value of the DT_DEBUG tag is filled in by the dynamic | |
1063 | // linker at run time, and used by the debugger. | |
1064 | odyn->add_constant(elfcpp::DT_DEBUG, 0); | |
1065 | } | |
1066 | } | |
1067 | ||
1068 | // Emit any relocs we saved in an attempt to avoid generating COPY | |
1069 | // relocs. | |
1070 | if (this->copy_relocs_ == NULL) | |
1071 | return; | |
1072 | if (this->copy_relocs_->any_to_emit()) | |
1073 | { | |
1074 | Reloc_section* rel_dyn = this->rel_dyn_section(layout); | |
1075 | this->copy_relocs_->emit(rel_dyn); | |
1076 | } | |
1077 | delete this->copy_relocs_; | |
1078 | this->copy_relocs_ = NULL; | |
1079 | } | |
1080 | ||
1081 | // Perform a relocation. | |
1082 | ||
1083 | inline bool | |
1084 | Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, | |
1085 | Target_x86_64* target, | |
1086 | size_t relnum, | |
1087 | const elfcpp::Rela<64, false>& rel, | |
1088 | unsigned int r_type, | |
1089 | const Sized_symbol<64>* gsym, | |
1090 | const Symbol_value<64>* psymval, | |
1091 | unsigned char* view, | |
1092 | elfcpp::Elf_types<64>::Elf_Addr address, | |
1093 | off_t view_size) | |
1094 | { | |
1095 | if (this->skip_call_tls_get_addr_) | |
1096 | { | |
1097 | if (r_type != elfcpp::R_X86_64_PLT32 | |
1098 | || gsym == NULL | |
1099 | || strcmp(gsym->name(), "___tls_get_addr") != 0) | |
1100 | { | |
1101 | fprintf(stderr, _("%s: %s: missing expected TLS relocation\n"), | |
1102 | program_name, | |
1103 | relinfo->location(relnum, rel.get_r_offset()).c_str()); | |
1104 | gold_exit(false); | |
1105 | } | |
1106 | ||
1107 | this->skip_call_tls_get_addr_ = false; | |
1108 | ||
1109 | return false; | |
1110 | } | |
1111 | ||
1112 | // Pick the value to use for symbols defined in shared objects. | |
1113 | Symbol_value<64> symval; | |
1114 | if (gsym != NULL && gsym->is_from_dynobj() && gsym->has_plt_offset()) | |
1115 | { | |
1116 | symval.set_output_value(target->plt_section()->address() | |
1117 | + gsym->plt_offset()); | |
1118 | psymval = &symval; | |
1119 | } | |
1120 | ||
1121 | const Sized_relobj<64, false>* object = relinfo->object; | |
1122 | const elfcpp::Elf_Xword addend = rel.get_r_addend(); | |
1123 | ||
1124 | switch (r_type) | |
1125 | { | |
1126 | case elfcpp::R_X86_64_NONE: | |
e822f2b1 ILT |
1127 | case elfcpp::R_386_GNU_VTINHERIT: |
1128 | case elfcpp::R_386_GNU_VTENTRY: | |
2e30d253 ILT |
1129 | break; |
1130 | ||
1131 | case elfcpp::R_X86_64_64: | |
1132 | Relocate_functions<64, false>::rela64(view, object, psymval, addend); | |
1133 | break; | |
1134 | ||
1135 | case elfcpp::R_X86_64_PC64: | |
1136 | Relocate_functions<64, false>::pcrela64(view, object, psymval, addend, | |
1137 | address); | |
1138 | break; | |
1139 | ||
1140 | case elfcpp::R_X86_64_32: | |
7bb3655e ILT |
1141 | // FIXME: we need to verify that value + addend fits into 32 bits: |
1142 | // uint64_t x = value + addend; | |
1143 | // x == static_cast<uint64_t>(static_cast<uint32_t>(x)) | |
1144 | // Likewise for other <=32-bit relocations (but see R_X86_64_32S). | |
2e30d253 ILT |
1145 | Relocate_functions<64, false>::rela32(view, object, psymval, addend); |
1146 | break; | |
1147 | ||
1148 | case elfcpp::R_X86_64_32S: | |
7bb3655e ILT |
1149 | // FIXME: we need to verify that value + addend fits into 32 bits: |
1150 | // int64_t x = value + addend; // note this quantity is signed! | |
1151 | // x == static_cast<int64_t>(static_cast<int32_t>(x)) | |
2e30d253 ILT |
1152 | Relocate_functions<64, false>::rela32(view, object, psymval, addend); |
1153 | break; | |
1154 | ||
1155 | case elfcpp::R_X86_64_PC32: | |
1156 | Relocate_functions<64, false>::pcrela32(view, object, psymval, addend, | |
1157 | address); | |
1158 | break; | |
1159 | ||
1160 | case elfcpp::R_X86_64_16: | |
1161 | Relocate_functions<64, false>::rela16(view, object, psymval, addend); | |
1162 | break; | |
1163 | ||
1164 | case elfcpp::R_X86_64_PC16: | |
1165 | Relocate_functions<64, false>::pcrela16(view, object, psymval, addend, | |
1166 | address); | |
1167 | break; | |
1168 | ||
1169 | case elfcpp::R_X86_64_8: | |
1170 | Relocate_functions<64, false>::rela8(view, object, psymval, addend); | |
1171 | break; | |
1172 | ||
1173 | case elfcpp::R_X86_64_PC8: | |
1174 | Relocate_functions<64, false>::pcrela8(view, object, psymval, addend, | |
1175 | address); | |
1176 | break; | |
1177 | ||
1178 | case elfcpp::R_X86_64_PLT32: | |
1179 | gold_assert(gsym->has_plt_offset() | |
1180 | || gsym->final_value_is_known()); | |
1181 | Relocate_functions<64, false>::pcrela32(view, object, psymval, addend, | |
1182 | address); | |
1183 | break; | |
1184 | ||
1185 | case elfcpp::R_X86_64_GOT32: | |
1186 | // Local GOT offsets not yet supported. | |
1187 | gold_assert(gsym); | |
1188 | gold_assert(gsym->has_got_offset()); | |
1189 | Relocate_functions<64, false>::rela32(view, gsym->got_offset(), addend); | |
1190 | break; | |
1191 | ||
e822f2b1 ILT |
1192 | case elfcpp::R_X86_64_GOTPC32: |
1193 | { | |
1194 | gold_assert(gsym); | |
1195 | elfcpp::Elf_types<64>::Elf_Addr value; | |
1196 | value = target->got_section(NULL, NULL)->address(); | |
1197 | Relocate_functions<64, false>::pcrela32(view, value, addend, address); | |
1198 | } | |
1199 | break; | |
1200 | ||
1201 | case elfcpp::R_X86_64_GOT64: | |
1202 | // The ABI doc says "Like GOT64, but indicates a PLT entry is needed." | |
1203 | // Since we always add a PLT entry, this is equivalent. | |
1204 | case elfcpp::R_X86_64_GOTPLT64: // TODO(csilvers): correct? | |
1205 | // Local GOT offsets not yet supported. | |
1206 | gold_assert(gsym); | |
1207 | gold_assert(gsym->has_got_offset()); | |
1208 | Relocate_functions<64, false>::rela64(view, gsym->got_offset(), addend); | |
1209 | break; | |
1210 | ||
1211 | case elfcpp::R_X86_64_GOTPC64: | |
1212 | { | |
1213 | gold_assert(gsym); | |
1214 | elfcpp::Elf_types<64>::Elf_Addr value; | |
1215 | value = target->got_section(NULL, NULL)->address(); | |
1216 | Relocate_functions<64, false>::pcrela64(view, value, addend, address); | |
1217 | } | |
1218 | break; | |
1219 | ||
2e30d253 ILT |
1220 | case elfcpp::R_X86_64_GOTOFF64: |
1221 | { | |
1222 | elfcpp::Elf_types<64>::Elf_Addr value; | |
1223 | value = (psymval->value(object, 0) | |
1224 | - target->got_section(NULL, NULL)->address()); | |
1225 | Relocate_functions<64, false>::rela64(view, value, addend); | |
1226 | } | |
1227 | break; | |
1228 | ||
1229 | case elfcpp::R_X86_64_GOTPCREL: | |
1230 | { | |
1231 | gold_assert(gsym); | |
1232 | elfcpp::Elf_types<64>::Elf_Addr value; | |
1233 | // FIXME(csilvers): this is probably totally wrong for G + GOT | |
1234 | value = (target->got_section(NULL, NULL)->address() | |
1235 | + (gsym->has_got_offset() ? gsym->got_offset() : 0)); | |
1236 | Relocate_functions<64, false>::pcrela32(view, value, addend, address); | |
1237 | } | |
1238 | break; | |
1239 | ||
e822f2b1 ILT |
1240 | case elfcpp::R_X86_64_GOTPCREL64: |
1241 | { | |
1242 | gold_assert(gsym); | |
1243 | elfcpp::Elf_types<64>::Elf_Addr value; | |
1244 | // FIXME(csilvers): this is probably totally wrong for G + GOT | |
1245 | value = (target->got_section(NULL, NULL)->address() | |
1246 | + (gsym->has_got_offset() ? gsym->got_offset() : 0)); | |
1247 | Relocate_functions<64, false>::pcrela64(view, value, addend, address); | |
1248 | } | |
1249 | break; | |
1250 | ||
2e30d253 ILT |
1251 | case elfcpp::R_X86_64_COPY: |
1252 | case elfcpp::R_X86_64_GLOB_DAT: | |
1253 | case elfcpp::R_X86_64_JUMP_SLOT: | |
1254 | case elfcpp::R_X86_64_RELATIVE: | |
1255 | case elfcpp::R_X86_64_TPOFF64: | |
1256 | case elfcpp::R_X86_64_TPOFF32: | |
1257 | case elfcpp::R_X86_64_DTPMOD64: | |
1258 | case elfcpp::R_X86_64_DTPOFF64: | |
1259 | case elfcpp::R_X86_64_DTPOFF32: | |
e822f2b1 | 1260 | case elfcpp::R_X86_64_GOTTPOFF: // TODO(csilvers): correct? |
2e30d253 | 1261 | case elfcpp::R_X86_64_TLSDESC: |
e822f2b1 ILT |
1262 | case elfcpp::R_X86_64_GOTPC32_TLSDESC: // TODO(csilvers): correct? |
1263 | case elfcpp::R_X86_64_TLSDESC_CALL: // TODO(csilvers): correct? | |
2e30d253 ILT |
1264 | fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), |
1265 | program_name, | |
1266 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1267 | r_type); | |
1268 | gold_exit(false); | |
1269 | break; | |
1270 | ||
1271 | #if 0 | |
e822f2b1 ILT |
1272 | case elfcpp::R_X86_64_TLSGD: // TODO(csilvers): correct? |
1273 | case elfcpp::R_X86_64_TLSLD: // TODO(csilvers): correct? | |
1274 | ||
1275 | case elfcpp::R_386_TLS_IE: | |
1276 | case elfcpp::R_386_TLS_GOTIE: | |
1277 | case elfcpp::R_386_TLS_LE: | |
1278 | case elfcpp::R_386_TLS_GD: | |
1279 | case elfcpp::R_386_TLS_LDM: | |
1280 | case elfcpp::R_386_TLS_LDO_64: | |
1281 | case elfcpp::R_386_TLS_IE_64: | |
1282 | case elfcpp::R_386_TLS_LE_64: | |
2e30d253 ILT |
1283 | this->relocate_tls(relinfo, relnum, rel, r_type, gsym, psymval, view, |
1284 | address, view_size); | |
1285 | break; | |
1286 | #else | |
1287 | view_size++; // this is to make view_size used | |
1288 | #endif | |
1289 | ||
e822f2b1 ILT |
1290 | case elfcpp::R_X86_64_SIZE32: // TODO(csilvers): correct? |
1291 | case elfcpp::R_X86_64_SIZE64: // TODO(csilvers): correct? | |
1292 | case elfcpp::R_X86_64_PLTOFF64: // TODO(csilvers): implement me! | |
2e30d253 | 1293 | #if 0 |
e822f2b1 ILT |
1294 | case elfcpp::R_386_TLS_GD_64: |
1295 | case elfcpp::R_386_TLS_GD_PUSH: | |
1296 | case elfcpp::R_386_TLS_GD_CALL: | |
1297 | case elfcpp::R_386_TLS_GD_POP: | |
1298 | case elfcpp::R_386_TLS_LDM_64: | |
1299 | case elfcpp::R_386_TLS_LDM_PUSH: | |
1300 | case elfcpp::R_386_TLS_LDM_CALL: | |
1301 | case elfcpp::R_386_TLS_LDM_POP: | |
2e30d253 ILT |
1302 | #endif |
1303 | default: | |
1304 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), | |
1305 | program_name, | |
1306 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1307 | r_type); | |
1308 | // gold_exit(false); | |
1309 | break; | |
1310 | } | |
1311 | ||
1312 | return true; | |
1313 | } | |
1314 | ||
1315 | // Perform a TLS relocation. | |
1316 | ||
1317 | inline void | |
1318 | Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>*, // relinfo, | |
1319 | size_t , // relnum, | |
1320 | const elfcpp::Rela<64, false>& , // rel, | |
1321 | unsigned int , // r_type, | |
1322 | const Sized_symbol<64>* , // gsym, | |
1323 | const Symbol_value<64>* , // psymval, | |
1324 | unsigned char* , // view, | |
1325 | elfcpp::Elf_types<64>::Elf_Addr, | |
1326 | off_t)// view_size) | |
1327 | { | |
1328 | #if 0 | |
1329 | Output_segment* tls_segment = relinfo->layout->tls_segment(); | |
1330 | if (tls_segment == NULL) | |
1331 | { | |
1332 | fprintf(stderr, _("%s: %s: TLS reloc but no TLS segment\n"), | |
1333 | program_name, | |
1334 | relinfo->location(relnum, rel.get_r_offset()).c_str()); | |
1335 | gold_exit(false); | |
1336 | } | |
1337 | ||
1338 | elfcpp::Elf_types<64>::Elf_Addr value = psymval->value(relinfo->object, 0); | |
1339 | ||
1340 | const bool is_final = (gsym == NULL | |
1341 | ? !parameters->output_is_shared() | |
1342 | : gsym->final_value_is_known()); | |
1343 | const unsigned int opt_r_type = | |
1344 | Target_x86_64::optimize_tls_reloc(is_final, r_type); | |
1345 | switch (r_type) | |
1346 | { | |
1347 | case elfcpp::R_X86_64_TLS_LE_64: | |
1348 | value = tls_segment->vaddr() + tls_segment->memsz() - value; | |
1349 | Relocate_functions<64, false>::rel64(view, value); | |
1350 | break; | |
1351 | ||
1352 | case elfcpp::R_X86_64_TLS_LE: | |
1353 | value = value - (tls_segment->vaddr() + tls_segment->memsz()); | |
1354 | Relocate_functions<64, false>::rel64(view, value); | |
1355 | break; | |
1356 | ||
1357 | case elfcpp::R_X86_64_TLS_IE: | |
1358 | case elfcpp::R_X86_64_TLS_GOTIE: | |
1359 | case elfcpp::R_X86_64_TLS_IE_64: | |
1360 | if (opt_r_type == elfcpp::R_X86_64_TLS_LE_64) | |
1361 | { | |
1362 | Target_x86_64::Relocate::tls_ie_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 type %u\n"), | |
1368 | program_name, | |
1369 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1370 | r_type); | |
1371 | // gold_exit(false); | |
1372 | break; | |
1373 | ||
1374 | case elfcpp::R_X86_64_TLS_GD: | |
1375 | if (opt_r_type == elfcpp::R_X86_64_TLS_LE_64) | |
1376 | { | |
1377 | this->tls_gd_to_le(relinfo, relnum, tls_segment, | |
1378 | rel, r_type, value, view, | |
1379 | view_size); | |
1380 | break; | |
1381 | } | |
1382 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), | |
1383 | program_name, | |
1384 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1385 | r_type); | |
1386 | // gold_exit(false); | |
1387 | break; | |
1388 | ||
1389 | case elfcpp::R_X86_64_TLS_LDM: | |
1390 | case elfcpp::R_X86_64_TLS_LDO_64: | |
1391 | fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), | |
1392 | program_name, | |
1393 | relinfo->location(relnum, rel.get_r_offset()).c_str(), | |
1394 | r_type); | |
1395 | // gold_exit(false); | |
1396 | break; | |
1397 | } | |
1398 | #endif | |
1399 | } | |
1400 | ||
1401 | // Do a relocation in which we convert a TLS Initial-Exec to a | |
1402 | // Local-Exec. | |
1403 | ||
1404 | inline void | |
1405 | Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info<64, false>* , // relinfo, | |
1406 | size_t , // relnum, | |
1407 | Output_segment* , // tls_segment, | |
1408 | const elfcpp::Rela<64, false>& , // rel, | |
1409 | unsigned int , // r_type, | |
1410 | elfcpp::Elf_types<64>::Elf_Addr , // value, | |
1411 | unsigned char* , // view, | |
1412 | off_t) // view_size) | |
1413 | { | |
1414 | #if 0 | |
1415 | // We have to actually change the instructions, which means that we | |
1416 | // need to examine the opcodes to figure out which instruction we | |
1417 | // are looking at. | |
1418 | if (r_type == elfcpp::R_X86_64_TLS_IE) | |
1419 | { | |
1420 | // movl %gs:XX,%eax ==> movl $YY,%eax | |
1421 | // movl %gs:XX,%reg ==> movl $YY,%reg | |
1422 | // addl %gs:XX,%reg ==> addl $YY,%reg | |
1423 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -1); | |
1424 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 4); | |
1425 | ||
1426 | unsigned char op1 = view[-1]; | |
1427 | if (op1 == 0xa1) | |
1428 | { | |
1429 | // movl XX,%eax ==> movl $YY,%eax | |
1430 | view[-1] = 0xb8; | |
1431 | } | |
1432 | else | |
1433 | { | |
1434 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, | |
1435 | view_size, -2); | |
1436 | ||
1437 | unsigned char op2 = view[-2]; | |
1438 | if (op2 == 0x8b) | |
1439 | { | |
1440 | // movl XX,%reg ==> movl $YY,%reg | |
1441 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1442 | (op1 & 0xc7) == 0x05); | |
1443 | view[-2] = 0xc7; | |
1444 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1445 | } | |
1446 | else if (op2 == 0x03) | |
1447 | { | |
1448 | // addl XX,%reg ==> addl $YY,%reg | |
1449 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1450 | (op1 & 0xc7) == 0x05); | |
1451 | view[-2] = 0x81; | |
1452 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1453 | } | |
1454 | else | |
1455 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, 0); | |
1456 | } | |
1457 | } | |
1458 | else | |
1459 | { | |
1460 | // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2 | |
1461 | // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2 | |
1462 | // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2 | |
1463 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -2); | |
1464 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 4); | |
1465 | ||
1466 | unsigned char op1 = view[-1]; | |
1467 | unsigned char op2 = view[-2]; | |
1468 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1469 | (op1 & 0xc0) == 0x80 && (op1 & 7) != 4); | |
1470 | if (op2 == 0x8b) | |
1471 | { | |
1472 | // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2 | |
1473 | view[-2] = 0xc7; | |
1474 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1475 | } | |
1476 | else if (op2 == 0x2b) | |
1477 | { | |
1478 | // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2 | |
1479 | view[-2] = 0x81; | |
1480 | view[-1] = 0xe8 | ((op1 >> 3) & 7); | |
1481 | } | |
1482 | else if (op2 == 0x03) | |
1483 | { | |
1484 | // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2 | |
1485 | view[-2] = 0x81; | |
1486 | view[-1] = 0xc0 | ((op1 >> 3) & 7); | |
1487 | } | |
1488 | else | |
1489 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, 0); | |
1490 | } | |
1491 | ||
1492 | value = tls_segment->vaddr() + tls_segment->memsz() - value; | |
1493 | if (r_type == elfcpp::R_X86_64_TLS_IE || r_type == elfcpp::R_X86_64_TLS_GOTIE) | |
1494 | value = - value; | |
1495 | ||
1496 | Relocate_functions<64, false>::rel64(view, value); | |
1497 | #endif | |
1498 | } | |
1499 | ||
1500 | // Do a relocation in which we convert a TLS Global-Dynamic to a | |
1501 | // Local-Exec. | |
1502 | ||
1503 | inline void | |
1504 | Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info<64, false>* , // relinfo, | |
1505 | size_t , // relnum, | |
1506 | Output_segment* , // tls_segment, | |
1507 | const elfcpp::Rela<64, false>& , // rel, | |
1508 | unsigned int, | |
1509 | elfcpp::Elf_types<64>::Elf_Addr , // value, | |
1510 | unsigned char* , // view, | |
1511 | off_t)// view_size) | |
1512 | { | |
1513 | #if 0 | |
1514 | // leal foo(,%reg,1),%eax; call ___tls_get_addr | |
1515 | // ==> movl %gs,0,%eax; subl $foo@tpoff,%eax | |
1516 | // leal foo(%reg),%eax; call ___tls_get_addr | |
1517 | // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax | |
1518 | ||
1519 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -2); | |
1520 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 9); | |
1521 | ||
1522 | unsigned char op1 = view[-1]; | |
1523 | unsigned char op2 = view[-2]; | |
1524 | ||
1525 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1526 | op2 == 0x8d || op2 == 0x04); | |
1527 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1528 | view[4] == 0xe8); | |
1529 | ||
1530 | int roff = 5; | |
1531 | ||
1532 | if (op2 == 0x04) | |
1533 | { | |
1534 | Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -3); | |
1535 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1536 | view[-3] == 0x8d); | |
1537 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1538 | ((op1 & 0xc7) == 0x05 | |
1539 | && op1 != (4 << 3))); | |
1540 | memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); | |
1541 | } | |
1542 | else | |
1543 | { | |
1544 | Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, | |
1545 | (op1 & 0xf8) == 0x80 && (op1 & 7) != 4); | |
1546 | if (rel.get_r_offset() + 9 < view_size && view[9] == 0x90) | |
1547 | { | |
1548 | // There is a trailing nop. Use the size byte subl. | |
1549 | memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); | |
1550 | roff = 6; | |
1551 | } | |
1552 | else | |
1553 | { | |
1554 | // Use the five byte subl. | |
1555 | memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11); | |
1556 | } | |
1557 | } | |
1558 | ||
1559 | value = tls_segment->vaddr() + tls_segment->memsz() - value; | |
1560 | Relocate_functions<64, false>::rel64(view + roff, value); | |
1561 | ||
1562 | // The next reloc should be a PLT32 reloc against __tls_get_addr. | |
1563 | // We can skip it. | |
1564 | this->skip_call_tls_get_addr_ = true; | |
1565 | #endif | |
1566 | } | |
1567 | ||
1568 | // Check the range for a TLS relocation. | |
1569 | ||
1570 | inline void | |
1571 | Target_x86_64::Relocate::check_range(const Relocate_info<64, false>* relinfo, | |
1572 | size_t relnum, | |
1573 | const elfcpp::Rela<64, false>& rel, | |
1574 | off_t view_size, off_t off) | |
1575 | { | |
1576 | off_t offset = rel.get_r_offset() + off; | |
1577 | if (offset < 0 || offset > view_size) | |
1578 | { | |
1579 | fprintf(stderr, _("%s: %s: TLS relocation out of range\n"), | |
1580 | program_name, | |
1581 | relinfo->location(relnum, rel.get_r_offset()).c_str()); | |
1582 | gold_exit(false); | |
1583 | } | |
1584 | } | |
1585 | ||
1586 | // Check the validity of a TLS relocation. This is like assert. | |
1587 | ||
1588 | inline void | |
1589 | Target_x86_64::Relocate::check_tls(const Relocate_info<64, false>* relinfo, | |
1590 | size_t relnum, | |
1591 | const elfcpp::Rela<64, false>& rel, | |
1592 | bool valid) | |
1593 | { | |
1594 | if (!valid) | |
1595 | { | |
1596 | fprintf(stderr, | |
1597 | _("%s: %s: TLS relocation against invalid instruction\n"), | |
1598 | program_name, | |
1599 | relinfo->location(relnum, rel.get_r_offset()).c_str()); | |
1600 | gold_exit(false); | |
1601 | } | |
1602 | } | |
1603 | ||
1604 | // Relocate section data. | |
1605 | ||
1606 | void | |
1607 | Target_x86_64::relocate_section(const Relocate_info<64, false>* relinfo, | |
1608 | unsigned int sh_type, | |
1609 | const unsigned char* prelocs, | |
1610 | size_t reloc_count, | |
1611 | unsigned char* view, | |
1612 | elfcpp::Elf_types<64>::Elf_Addr address, | |
1613 | off_t view_size) | |
1614 | { | |
1615 | gold_assert(sh_type == elfcpp::SHT_RELA); | |
1616 | ||
1617 | gold::relocate_section<64, false, Target_x86_64, elfcpp::SHT_RELA, | |
1618 | Target_x86_64::Relocate>( | |
1619 | relinfo, | |
1620 | this, | |
1621 | prelocs, | |
1622 | reloc_count, | |
1623 | view, | |
1624 | address, | |
1625 | view_size); | |
1626 | } | |
1627 | ||
4fb6c25d ILT |
1628 | // Return the value to use for a dynamic which requires special |
1629 | // treatment. This is how we support equality comparisons of function | |
1630 | // pointers across shared library boundaries, as described in the | |
1631 | // processor specific ABI supplement. | |
1632 | ||
1633 | uint64_t | |
1634 | Target_x86_64::do_dynsym_value(const Symbol* gsym) const | |
1635 | { | |
1636 | gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset()); | |
1637 | return this->plt_section()->address() + gsym->plt_offset(); | |
1638 | } | |
1639 | ||
2e30d253 ILT |
1640 | // Return a string used to fill a code section with nops to take up |
1641 | // the specified length. | |
1642 | ||
1643 | std::string | |
1644 | Target_x86_64::do_code_fill(off_t length) | |
1645 | { | |
1646 | if (length >= 16) | |
1647 | { | |
1648 | // Build a jmpq instruction to skip over the bytes. | |
1649 | unsigned char jmp[5]; | |
1650 | jmp[0] = 0xe9; | |
1651 | elfcpp::Swap_unaligned<64, false>::writeval(jmp + 1, length - 5); | |
1652 | return (std::string(reinterpret_cast<char*>(&jmp[0]), 5) | |
1653 | + std::string(length - 5, '\0')); | |
1654 | } | |
1655 | ||
1656 | // Nop sequences of various lengths. | |
1657 | const char nop1[1] = { 0x90 }; // nop | |
1658 | const char nop2[2] = { 0x66, 0x90 }; // xchg %ax %ax | |
1659 | const char nop3[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi | |
1660 | const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi | |
1661 | const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26, // nop | |
1662 | 0x00 }; // leal 0(%esi,1),%esi | |
1663 | const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi | |
1664 | 0x00, 0x00 }; | |
1665 | const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi | |
1666 | 0x00, 0x00, 0x00 }; | |
1667 | const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop | |
1668 | 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi | |
1669 | const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi | |
1670 | 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi | |
1671 | 0x00 }; | |
1672 | const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi | |
1673 | 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi | |
1674 | 0x00, 0x00 }; | |
1675 | const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi | |
1676 | 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi | |
1677 | 0x00, 0x00, 0x00 }; | |
1678 | const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi | |
1679 | 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi | |
1680 | 0x00, 0x00, 0x00, 0x00 }; | |
1681 | const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi | |
1682 | 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi | |
1683 | 0x27, 0x00, 0x00, 0x00, | |
1684 | 0x00 }; | |
1685 | const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi | |
1686 | 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi | |
1687 | 0xbc, 0x27, 0x00, 0x00, | |
1688 | 0x00, 0x00 }; | |
1689 | const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15 | |
1690 | 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,... | |
1691 | 0x90, 0x90, 0x90, 0x90, | |
1692 | 0x90, 0x90, 0x90 }; | |
1693 | ||
1694 | const char* nops[16] = { | |
1695 | NULL, | |
1696 | nop1, nop2, nop3, nop4, nop5, nop6, nop7, | |
1697 | nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15 | |
1698 | }; | |
1699 | ||
1700 | return std::string(nops[length], length); | |
1701 | } | |
1702 | ||
1703 | // The selector for x86_64 object files. | |
1704 | ||
1705 | class Target_selector_x86_64 : public Target_selector | |
1706 | { | |
1707 | public: | |
1708 | Target_selector_x86_64() | |
1709 | : Target_selector(elfcpp::EM_X86_64, 64, false) | |
1710 | { } | |
1711 | ||
1712 | Target* | |
1713 | recognize(int machine, int osabi, int abiversion); | |
1714 | ||
1715 | private: | |
1716 | Target_x86_64* target_; | |
1717 | }; | |
1718 | ||
1719 | // Recognize an x86_64 object file when we already know that the machine | |
1720 | // number is EM_X86_64. | |
1721 | ||
1722 | Target* | |
1723 | Target_selector_x86_64::recognize(int, int, int) | |
1724 | { | |
1725 | if (this->target_ == NULL) | |
1726 | this->target_ = new Target_x86_64(); | |
1727 | return this->target_; | |
1728 | } | |
1729 | ||
1730 | Target_selector_x86_64 target_selector_x86_64; | |
1731 | ||
1732 | } // End anonymous namespace. |