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4a657b0d DK |
1 | // arm.cc -- arm target support for gold. |
2 | ||
3 | // Copyright 2009 Free Software Foundation, Inc. | |
4 | // Written by Doug Kwan <dougkwan@google.com> based on the i386 code | |
5 | // by Ian Lance Taylor <iant@google.com>. | |
6 | ||
7 | // This file is part of gold. | |
8 | ||
9 | // This program is free software; you can redistribute it and/or modify | |
10 | // it under the terms of the GNU General Public License as published by | |
11 | // the Free Software Foundation; either version 3 of the License, or | |
12 | // (at your option) any later version. | |
13 | ||
14 | // This program is distributed in the hope that it will be useful, | |
15 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | // GNU General Public License for more details. | |
18 | ||
19 | // You should have received a copy of the GNU General Public License | |
20 | // along with this program; if not, write to the Free Software | |
21 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, | |
22 | // MA 02110-1301, USA. | |
23 | ||
24 | #include "gold.h" | |
25 | ||
26 | #include <cstring> | |
27 | #include <limits> | |
28 | #include <cstdio> | |
29 | #include <string> | |
30 | ||
31 | #include "elfcpp.h" | |
32 | #include "parameters.h" | |
33 | #include "reloc.h" | |
34 | #include "arm.h" | |
35 | #include "object.h" | |
36 | #include "symtab.h" | |
37 | #include "layout.h" | |
38 | #include "output.h" | |
39 | #include "copy-relocs.h" | |
40 | #include "target.h" | |
41 | #include "target-reloc.h" | |
42 | #include "target-select.h" | |
43 | #include "tls.h" | |
44 | #include "defstd.h" | |
45 | ||
46 | namespace | |
47 | { | |
48 | ||
49 | using namespace gold; | |
50 | ||
94cdfcff DK |
51 | template<bool big_endian> |
52 | class Output_data_plt_arm; | |
53 | ||
4a657b0d DK |
54 | // The arm target class. |
55 | // | |
56 | // This is a very simple port of gold for ARM-EABI. It is intended for | |
57 | // supporting Android only for the time being. Only these relocation types | |
58 | // are supported. | |
59 | // | |
60 | // R_ARM_NONE | |
61 | // R_ARM_ABS32 | |
62 | // R_ARM_REL32 | |
63 | // R_ARM_THM_CALL | |
64 | // R_ARM_COPY | |
65 | // R_ARM_GLOB_DAT | |
66 | // R_ARM_BASE_PREL | |
67 | // R_ARM_JUMP_SLOT | |
68 | // R_ARM_RELATIVE | |
69 | // R_ARM_GOTOFF32 | |
70 | // R_ARM_GOT_BREL | |
71 | // R_ARM_PLT32 | |
72 | // R_ARM_CALL | |
73 | // R_ARM_JUMP24 | |
74 | // R_ARM_TARGET1 | |
75 | // R_ARM_PREL31 | |
76 | // | |
4a657b0d | 77 | // TODOs: |
11af873f DK |
78 | // - Generate various branch stubs. |
79 | // - Support interworking. | |
80 | // - Define section symbols __exidx_start and __exidx_stop. | |
4a657b0d | 81 | // - Support more relocation types as needed. |
94cdfcff DK |
82 | // - Make PLTs more flexible for different architecture features like |
83 | // Thumb-2 and BE8. | |
11af873f | 84 | // There are probably a lot more. |
4a657b0d | 85 | |
c121c671 DK |
86 | // Utilities for manipulating integers of up to 32-bits |
87 | ||
88 | namespace utils | |
89 | { | |
90 | // Sign extend an n-bit unsigned integer stored in an uint32_t into | |
91 | // an int32_t. NO_BITS must be between 1 to 32. | |
92 | template<int no_bits> | |
93 | static inline int32_t | |
94 | sign_extend(uint32_t bits) | |
95 | { | |
96d49306 | 96 | gold_assert(no_bits >= 0 && no_bits <= 32); |
c121c671 DK |
97 | if (no_bits == 32) |
98 | return static_cast<int32_t>(bits); | |
99 | uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits); | |
100 | bits &= mask; | |
101 | uint32_t top_bit = 1U << (no_bits - 1); | |
102 | int32_t as_signed = static_cast<int32_t>(bits); | |
103 | return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed; | |
104 | } | |
105 | ||
106 | // Detects overflow of an NO_BITS integer stored in a uint32_t. | |
107 | template<int no_bits> | |
108 | static inline bool | |
109 | has_overflow(uint32_t bits) | |
110 | { | |
96d49306 | 111 | gold_assert(no_bits >= 0 && no_bits <= 32); |
c121c671 DK |
112 | if (no_bits == 32) |
113 | return false; | |
114 | int32_t max = (1 << (no_bits - 1)) - 1; | |
115 | int32_t min = -(1 << (no_bits - 1)); | |
116 | int32_t as_signed = static_cast<int32_t>(bits); | |
117 | return as_signed > max || as_signed < min; | |
118 | } | |
119 | ||
5e445df6 ILT |
120 | // Detects overflow of an NO_BITS integer stored in a uint32_t when it |
121 | // fits in the given number of bits as either a signed or unsigned value. | |
122 | // For example, has_signed_unsigned_overflow<8> would check | |
123 | // -128 <= bits <= 255 | |
124 | template<int no_bits> | |
125 | static inline bool | |
126 | has_signed_unsigned_overflow(uint32_t bits) | |
127 | { | |
128 | gold_assert(no_bits >= 2 && no_bits <= 32); | |
129 | if (no_bits == 32) | |
130 | return false; | |
131 | int32_t max = static_cast<int32_t>((1U << no_bits) - 1); | |
132 | int32_t min = -(1 << (no_bits - 1)); | |
133 | int32_t as_signed = static_cast<int32_t>(bits); | |
134 | return as_signed > max || as_signed < min; | |
135 | } | |
136 | ||
c121c671 DK |
137 | // Select bits from A and B using bits in MASK. For each n in [0..31], |
138 | // the n-th bit in the result is chosen from the n-th bits of A and B. | |
139 | // A zero selects A and a one selects B. | |
140 | static inline uint32_t | |
141 | bit_select(uint32_t a, uint32_t b, uint32_t mask) | |
142 | { return (a & ~mask) | (b & mask); } | |
143 | }; | |
144 | ||
4a657b0d DK |
145 | template<bool big_endian> |
146 | class Target_arm : public Sized_target<32, big_endian> | |
147 | { | |
148 | public: | |
149 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian> | |
150 | Reloc_section; | |
151 | ||
152 | Target_arm() | |
94cdfcff DK |
153 | : Sized_target<32, big_endian>(&arm_info), |
154 | got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), | |
155 | copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL) | |
4a657b0d DK |
156 | { } |
157 | ||
158 | // Process the relocations to determine unreferenced sections for | |
159 | // garbage collection. | |
160 | void | |
161 | gc_process_relocs(const General_options& options, | |
162 | Symbol_table* symtab, | |
163 | Layout* layout, | |
164 | Sized_relobj<32, big_endian>* object, | |
165 | unsigned int data_shndx, | |
166 | unsigned int sh_type, | |
167 | const unsigned char* prelocs, | |
168 | size_t reloc_count, | |
169 | Output_section* output_section, | |
170 | bool needs_special_offset_handling, | |
171 | size_t local_symbol_count, | |
172 | const unsigned char* plocal_symbols); | |
173 | ||
174 | // Scan the relocations to look for symbol adjustments. | |
175 | void | |
176 | scan_relocs(const General_options& options, | |
177 | Symbol_table* symtab, | |
178 | Layout* layout, | |
179 | Sized_relobj<32, big_endian>* object, | |
180 | unsigned int data_shndx, | |
181 | unsigned int sh_type, | |
182 | const unsigned char* prelocs, | |
183 | size_t reloc_count, | |
184 | Output_section* output_section, | |
185 | bool needs_special_offset_handling, | |
186 | size_t local_symbol_count, | |
187 | const unsigned char* plocal_symbols); | |
188 | ||
189 | // Finalize the sections. | |
190 | void | |
191 | do_finalize_sections(Layout*); | |
192 | ||
94cdfcff | 193 | // Return the value to use for a dynamic symbol which requires special |
4a657b0d DK |
194 | // treatment. |
195 | uint64_t | |
196 | do_dynsym_value(const Symbol*) const; | |
197 | ||
198 | // Relocate a section. | |
199 | void | |
200 | relocate_section(const Relocate_info<32, big_endian>*, | |
201 | unsigned int sh_type, | |
202 | const unsigned char* prelocs, | |
203 | size_t reloc_count, | |
204 | Output_section* output_section, | |
205 | bool needs_special_offset_handling, | |
206 | unsigned char* view, | |
207 | elfcpp::Elf_types<32>::Elf_Addr view_address, | |
208 | section_size_type view_size); | |
209 | ||
210 | // Scan the relocs during a relocatable link. | |
211 | void | |
212 | scan_relocatable_relocs(const General_options& options, | |
213 | Symbol_table* symtab, | |
214 | Layout* layout, | |
215 | Sized_relobj<32, big_endian>* object, | |
216 | unsigned int data_shndx, | |
217 | unsigned int sh_type, | |
218 | const unsigned char* prelocs, | |
219 | size_t reloc_count, | |
220 | Output_section* output_section, | |
221 | bool needs_special_offset_handling, | |
222 | size_t local_symbol_count, | |
223 | const unsigned char* plocal_symbols, | |
224 | Relocatable_relocs*); | |
225 | ||
226 | // Relocate a section during a relocatable link. | |
227 | void | |
228 | relocate_for_relocatable(const Relocate_info<32, big_endian>*, | |
229 | unsigned int sh_type, | |
230 | const unsigned char* prelocs, | |
231 | size_t reloc_count, | |
232 | Output_section* output_section, | |
233 | off_t offset_in_output_section, | |
234 | const Relocatable_relocs*, | |
235 | unsigned char* view, | |
236 | elfcpp::Elf_types<32>::Elf_Addr view_address, | |
237 | section_size_type view_size, | |
238 | unsigned char* reloc_view, | |
239 | section_size_type reloc_view_size); | |
240 | ||
241 | // Return whether SYM is defined by the ABI. | |
242 | bool | |
243 | do_is_defined_by_abi(Symbol* sym) const | |
244 | { return strcmp(sym->name(), "__tls_get_addr") == 0; } | |
245 | ||
94cdfcff DK |
246 | // Return the size of the GOT section. |
247 | section_size_type | |
248 | got_size() | |
249 | { | |
250 | gold_assert(this->got_ != NULL); | |
251 | return this->got_->data_size(); | |
252 | } | |
253 | ||
4a657b0d DK |
254 | // Map platform-specific reloc types |
255 | static unsigned int | |
256 | get_real_reloc_type (unsigned int r_type); | |
257 | ||
258 | private: | |
259 | // The class which scans relocations. | |
260 | class Scan | |
261 | { | |
262 | public: | |
263 | Scan() | |
bec53400 | 264 | : issued_non_pic_error_(false) |
4a657b0d DK |
265 | { } |
266 | ||
267 | inline void | |
268 | local(const General_options& options, Symbol_table* symtab, | |
269 | Layout* layout, Target_arm* target, | |
270 | Sized_relobj<32, big_endian>* object, | |
271 | unsigned int data_shndx, | |
272 | Output_section* output_section, | |
273 | const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type, | |
274 | const elfcpp::Sym<32, big_endian>& lsym); | |
275 | ||
276 | inline void | |
277 | global(const General_options& options, Symbol_table* symtab, | |
278 | Layout* layout, Target_arm* target, | |
279 | Sized_relobj<32, big_endian>* object, | |
280 | unsigned int data_shndx, | |
281 | Output_section* output_section, | |
282 | const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type, | |
283 | Symbol* gsym); | |
284 | ||
285 | private: | |
286 | static void | |
287 | unsupported_reloc_local(Sized_relobj<32, big_endian>*, | |
288 | unsigned int r_type); | |
289 | ||
290 | static void | |
291 | unsupported_reloc_global(Sized_relobj<32, big_endian>*, | |
292 | unsigned int r_type, Symbol*); | |
bec53400 DK |
293 | |
294 | void | |
295 | check_non_pic(Relobj*, unsigned int r_type); | |
296 | ||
297 | // Almost identical to Symbol::needs_plt_entry except that it also | |
298 | // handles STT_ARM_TFUNC. | |
299 | static bool | |
300 | symbol_needs_plt_entry(const Symbol* sym) | |
301 | { | |
302 | // An undefined symbol from an executable does not need a PLT entry. | |
303 | if (sym->is_undefined() && !parameters->options().shared()) | |
304 | return false; | |
305 | ||
306 | return (!parameters->doing_static_link() | |
307 | && (sym->type() == elfcpp::STT_FUNC | |
308 | || sym->type() == elfcpp::STT_ARM_TFUNC) | |
309 | && (sym->is_from_dynobj() | |
310 | || sym->is_undefined() | |
311 | || sym->is_preemptible())); | |
312 | } | |
313 | ||
314 | // Whether we have issued an error about a non-PIC compilation. | |
315 | bool issued_non_pic_error_; | |
4a657b0d DK |
316 | }; |
317 | ||
318 | // The class which implements relocation. | |
319 | class Relocate | |
320 | { | |
321 | public: | |
322 | Relocate() | |
323 | { } | |
324 | ||
325 | ~Relocate() | |
326 | { } | |
327 | ||
bec53400 DK |
328 | // Return whether the static relocation needs to be applied. |
329 | inline bool | |
330 | should_apply_static_reloc(const Sized_symbol<32>* gsym, | |
331 | int ref_flags, | |
332 | bool is_32bit, | |
333 | Output_section* output_section); | |
334 | ||
4a657b0d DK |
335 | // Do a relocation. Return false if the caller should not issue |
336 | // any warnings about this relocation. | |
337 | inline bool | |
338 | relocate(const Relocate_info<32, big_endian>*, Target_arm*, | |
339 | Output_section*, size_t relnum, | |
340 | const elfcpp::Rel<32, big_endian>&, | |
341 | unsigned int r_type, const Sized_symbol<32>*, | |
342 | const Symbol_value<32>*, | |
343 | unsigned char*, elfcpp::Elf_types<32>::Elf_Addr, | |
344 | section_size_type); | |
c121c671 DK |
345 | |
346 | // Return whether we want to pass flag NON_PIC_REF for this | |
347 | // reloc. | |
348 | static inline bool | |
349 | reloc_is_non_pic (unsigned int r_type) | |
350 | { | |
351 | switch (r_type) | |
352 | { | |
353 | case elfcpp::R_ARM_REL32: | |
354 | case elfcpp::R_ARM_THM_CALL: | |
355 | case elfcpp::R_ARM_CALL: | |
356 | case elfcpp::R_ARM_JUMP24: | |
357 | case elfcpp::R_ARM_PREL31: | |
358 | return true; | |
359 | default: | |
360 | return false; | |
361 | } | |
362 | } | |
4a657b0d DK |
363 | }; |
364 | ||
365 | // A class which returns the size required for a relocation type, | |
366 | // used while scanning relocs during a relocatable link. | |
367 | class Relocatable_size_for_reloc | |
368 | { | |
369 | public: | |
370 | unsigned int | |
371 | get_size_for_reloc(unsigned int, Relobj*); | |
372 | }; | |
373 | ||
94cdfcff DK |
374 | // Get the GOT section, creating it if necessary. |
375 | Output_data_got<32, big_endian>* | |
376 | got_section(Symbol_table*, Layout*); | |
377 | ||
378 | // Get the GOT PLT section. | |
379 | Output_data_space* | |
380 | got_plt_section() const | |
381 | { | |
382 | gold_assert(this->got_plt_ != NULL); | |
383 | return this->got_plt_; | |
384 | } | |
385 | ||
386 | // Create a PLT entry for a global symbol. | |
387 | void | |
388 | make_plt_entry(Symbol_table*, Layout*, Symbol*); | |
389 | ||
390 | // Get the PLT section. | |
391 | const Output_data_plt_arm<big_endian>* | |
392 | plt_section() const | |
393 | { | |
394 | gold_assert(this->plt_ != NULL); | |
395 | return this->plt_; | |
396 | } | |
397 | ||
398 | // Get the dynamic reloc section, creating it if necessary. | |
399 | Reloc_section* | |
400 | rel_dyn_section(Layout*); | |
401 | ||
402 | // Return true if the symbol may need a COPY relocation. | |
403 | // References from an executable object to non-function symbols | |
404 | // defined in a dynamic object may need a COPY relocation. | |
405 | bool | |
406 | may_need_copy_reloc(Symbol* gsym) | |
407 | { | |
408 | return (!parameters->options().shared() | |
409 | && gsym->is_from_dynobj() | |
bec53400 DK |
410 | && gsym->type() != elfcpp::STT_FUNC |
411 | && gsym->type() != elfcpp::STT_ARM_TFUNC); | |
94cdfcff DK |
412 | } |
413 | ||
414 | // Add a potential copy relocation. | |
415 | void | |
416 | copy_reloc(Symbol_table* symtab, Layout* layout, | |
417 | Sized_relobj<32, big_endian>* object, | |
418 | unsigned int shndx, Output_section* output_section, | |
419 | Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc) | |
420 | { | |
421 | this->copy_relocs_.copy_reloc(symtab, layout, | |
422 | symtab->get_sized_symbol<32>(sym), | |
423 | object, shndx, output_section, reloc, | |
424 | this->rel_dyn_section(layout)); | |
425 | } | |
426 | ||
4a657b0d DK |
427 | // Information about this specific target which we pass to the |
428 | // general Target structure. | |
429 | static const Target::Target_info arm_info; | |
94cdfcff DK |
430 | |
431 | // The types of GOT entries needed for this platform. | |
432 | enum Got_type | |
433 | { | |
434 | GOT_TYPE_STANDARD = 0 // GOT entry for a regular symbol | |
435 | }; | |
436 | ||
437 | // The GOT section. | |
438 | Output_data_got<32, big_endian>* got_; | |
439 | // The PLT section. | |
440 | Output_data_plt_arm<big_endian>* plt_; | |
441 | // The GOT PLT section. | |
442 | Output_data_space* got_plt_; | |
443 | // The dynamic reloc section. | |
444 | Reloc_section* rel_dyn_; | |
445 | // Relocs saved to avoid a COPY reloc. | |
446 | Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_; | |
447 | // Space for variables copied with a COPY reloc. | |
448 | Output_data_space* dynbss_; | |
4a657b0d DK |
449 | }; |
450 | ||
451 | template<bool big_endian> | |
452 | const Target::Target_info Target_arm<big_endian>::arm_info = | |
453 | { | |
454 | 32, // size | |
455 | big_endian, // is_big_endian | |
456 | elfcpp::EM_ARM, // machine_code | |
457 | false, // has_make_symbol | |
458 | false, // has_resolve | |
459 | false, // has_code_fill | |
460 | true, // is_default_stack_executable | |
461 | '\0', // wrap_char | |
462 | "/usr/lib/libc.so.1", // dynamic_linker | |
463 | 0x8000, // default_text_segment_address | |
464 | 0x1000, // abi_pagesize (overridable by -z max-page-size) | |
8a5e3e08 ILT |
465 | 0x1000, // common_pagesize (overridable by -z common-page-size) |
466 | elfcpp::SHN_UNDEF, // small_common_shndx | |
467 | elfcpp::SHN_UNDEF, // large_common_shndx | |
468 | 0, // small_common_section_flags | |
469 | 0 // large_common_section_flags | |
4a657b0d DK |
470 | }; |
471 | ||
c121c671 DK |
472 | // Arm relocate functions class |
473 | // | |
474 | ||
475 | template<bool big_endian> | |
476 | class Arm_relocate_functions : public Relocate_functions<32, big_endian> | |
477 | { | |
478 | public: | |
479 | typedef enum | |
480 | { | |
481 | STATUS_OKAY, // No error during relocation. | |
482 | STATUS_OVERFLOW, // Relocation oveflow. | |
483 | STATUS_BAD_RELOC // Relocation cannot be applied. | |
484 | } Status; | |
485 | ||
486 | private: | |
487 | typedef Relocate_functions<32, big_endian> Base; | |
488 | typedef Arm_relocate_functions<big_endian> This; | |
489 | ||
490 | // Get an symbol value of *PSYMVAL with an ADDEND. This is a wrapper | |
491 | // to Symbol_value::value(). If HAS_THUMB_BIT is true, that LSB is used | |
492 | // to distinguish ARM and THUMB functions and it is treated specially. | |
493 | static inline Symbol_value<32>::Value | |
494 | arm_symbol_value (const Sized_relobj<32, big_endian> *object, | |
495 | const Symbol_value<32>* psymval, | |
496 | Symbol_value<32>::Value addend, | |
497 | bool has_thumb_bit) | |
498 | { | |
499 | typedef Symbol_value<32>::Value Valtype; | |
500 | ||
501 | if (has_thumb_bit) | |
502 | { | |
503 | Valtype raw = psymval->value(object, 0); | |
504 | Valtype thumb_bit = raw & 1; | |
505 | return ((raw & ~((Valtype) 1)) + addend) | thumb_bit; | |
506 | } | |
507 | else | |
508 | return psymval->value(object, addend); | |
509 | } | |
510 | ||
511 | // FIXME: This probably only works for Android on ARM v5te. We should | |
512 | // following GNU ld for the general case. | |
513 | template<unsigned r_type> | |
514 | static inline typename This::Status | |
515 | arm_branch_common(unsigned char *view, | |
516 | const Sized_relobj<32, big_endian>* object, | |
517 | const Symbol_value<32>* psymval, | |
518 | elfcpp::Elf_types<32>::Elf_Addr address, | |
519 | bool has_thumb_bit) | |
520 | { | |
521 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; | |
522 | Valtype* wv = reinterpret_cast<Valtype*>(view); | |
523 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); | |
524 | ||
525 | bool insn_is_b = (((val >> 28) & 0xf) <= 0xe) | |
526 | && ((val & 0x0f000000UL) == 0x0a000000UL); | |
527 | bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL; | |
528 | bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe) | |
529 | && ((val & 0x0f000000UL) == 0x0b000000UL); | |
530 | bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL; | |
531 | bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL; | |
532 | ||
533 | if (r_type == elfcpp::R_ARM_CALL) | |
534 | { | |
535 | if (!insn_is_uncond_bl && !insn_is_blx) | |
536 | return This::STATUS_BAD_RELOC; | |
537 | } | |
538 | else if (r_type == elfcpp::R_ARM_JUMP24) | |
539 | { | |
540 | if (!insn_is_b && !insn_is_cond_bl) | |
541 | return This::STATUS_BAD_RELOC; | |
542 | } | |
543 | else if (r_type == elfcpp::R_ARM_PLT32) | |
544 | { | |
545 | if (!insn_is_any_branch) | |
546 | return This::STATUS_BAD_RELOC; | |
547 | } | |
548 | else | |
549 | gold_unreachable(); | |
550 | ||
551 | Valtype addend = utils::sign_extend<26>(val << 2); | |
552 | Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit) | |
553 | - address); | |
554 | ||
555 | // If target has thumb bit set, we need to either turn the BL | |
556 | // into a BLX (for ARMv5 or above) or generate a stub. | |
557 | if (x & 1) | |
558 | { | |
559 | // Turn BL to BLX. | |
560 | if (insn_is_uncond_bl) | |
561 | val = (val & 0xffffff) | 0xfa000000 | ((x & 2) << 23); | |
562 | else | |
563 | return This::STATUS_BAD_RELOC; | |
564 | } | |
565 | else | |
566 | gold_assert(!insn_is_blx); | |
567 | ||
568 | val = utils::bit_select(val, (x >> 2), 0xffffffUL); | |
569 | elfcpp::Swap<32, big_endian>::writeval(wv, val); | |
570 | return (utils::has_overflow<26>(x) | |
571 | ? This::STATUS_OVERFLOW : This::STATUS_OKAY); | |
572 | } | |
573 | ||
574 | public: | |
5e445df6 ILT |
575 | |
576 | // R_ARM_ABS8: S + A | |
577 | static inline typename This::Status | |
578 | abs8(unsigned char *view, | |
579 | const Sized_relobj<32, big_endian>* object, | |
580 | const Symbol_value<32>* psymval, bool has_thumb_bit) | |
581 | { | |
582 | typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype; | |
583 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; | |
584 | Valtype* wv = reinterpret_cast<Valtype*>(view); | |
585 | Valtype val = elfcpp::Swap<8, big_endian>::readval(wv); | |
586 | Reltype addend = utils::sign_extend<8>(val); | |
587 | Reltype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit); | |
588 | val = utils::bit_select(val, x, 0xffU); | |
589 | elfcpp::Swap<8, big_endian>::writeval(wv, val); | |
590 | return (utils::has_signed_unsigned_overflow<8>(x) | |
591 | ? This::STATUS_OVERFLOW | |
592 | : This::STATUS_OKAY); | |
593 | } | |
594 | ||
c121c671 DK |
595 | // R_ARM_ABS32: (S + A) | T |
596 | static inline typename This::Status | |
597 | abs32(unsigned char *view, | |
598 | const Sized_relobj<32, big_endian>* object, | |
599 | const Symbol_value<32>* psymval, | |
600 | bool has_thumb_bit) | |
601 | { | |
602 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; | |
603 | Valtype* wv = reinterpret_cast<Valtype*>(view); | |
604 | Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv); | |
605 | Valtype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit); | |
606 | elfcpp::Swap<32, big_endian>::writeval(wv, x); | |
607 | return This::STATUS_OKAY; | |
608 | } | |
609 | ||
610 | // R_ARM_REL32: (S + A) | T - P | |
611 | static inline typename This::Status | |
612 | rel32(unsigned char *view, | |
613 | const Sized_relobj<32, big_endian>* object, | |
614 | const Symbol_value<32>* psymval, | |
615 | elfcpp::Elf_types<32>::Elf_Addr address, | |
616 | bool has_thumb_bit) | |
617 | { | |
618 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; | |
619 | Valtype* wv = reinterpret_cast<Valtype*>(view); | |
620 | Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv); | |
621 | Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit) | |
622 | - address); | |
623 | elfcpp::Swap<32, big_endian>::writeval(wv, x); | |
624 | return This::STATUS_OKAY; | |
625 | } | |
626 | ||
627 | // R_ARM_THM_CALL: (S + A) | T - P | |
628 | static inline typename This::Status | |
629 | thm_call(unsigned char *view, | |
630 | const Sized_relobj<32, big_endian>* object, | |
631 | const Symbol_value<32>* psymval, | |
632 | elfcpp::Elf_types<32>::Elf_Addr address, | |
633 | bool has_thumb_bit) | |
634 | { | |
635 | // A thumb call consists of two instructions. | |
636 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; | |
637 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; | |
638 | Valtype* wv = reinterpret_cast<Valtype*>(view); | |
639 | Valtype hi = elfcpp::Swap<16, big_endian>::readval(wv); | |
640 | Valtype lo = elfcpp::Swap<16, big_endian>::readval(wv + 1); | |
641 | // Must be a BL instruction. lo == 11111xxxxxxxxxxx. | |
642 | gold_assert((lo & 0xf800) == 0xf800); | |
643 | Reltype addend = utils::sign_extend<23>(((hi & 0x7ff) << 12) | |
644 | | ((lo & 0x7ff) << 1)); | |
645 | Reltype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit) | |
646 | - address); | |
647 | ||
648 | // If target has no thumb bit set, we need to either turn the BL | |
649 | // into a BLX (for ARMv5 or above) or generate a stub. | |
650 | if ((x & 1) == 0) | |
651 | { | |
652 | // This only works for ARMv5 and above with interworking enabled. | |
653 | lo &= 0xefff; | |
654 | } | |
655 | hi = utils::bit_select(hi, (x >> 12), 0x7ffU); | |
656 | lo = utils::bit_select(lo, (x >> 1), 0x7ffU); | |
657 | elfcpp::Swap<16, big_endian>::writeval(wv, hi); | |
658 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, lo); | |
659 | return (utils::has_overflow<23>(x) | |
660 | ? This::STATUS_OVERFLOW | |
661 | : This::STATUS_OKAY); | |
662 | } | |
663 | ||
664 | // R_ARM_BASE_PREL: B(S) + A - P | |
665 | static inline typename This::Status | |
666 | base_prel(unsigned char* view, | |
667 | elfcpp::Elf_types<32>::Elf_Addr origin, | |
668 | elfcpp::Elf_types<32>::Elf_Addr address) | |
669 | { | |
670 | Base::rel32(view, origin - address); | |
671 | return STATUS_OKAY; | |
672 | } | |
673 | ||
674 | // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG | |
675 | static inline typename This::Status | |
676 | got_brel(unsigned char* view, | |
677 | typename elfcpp::Swap<32, big_endian>::Valtype got_offset) | |
678 | { | |
679 | Base::rel32(view, got_offset); | |
680 | return This::STATUS_OKAY; | |
681 | } | |
682 | ||
683 | // R_ARM_PLT32: (S + A) | T - P | |
684 | static inline typename This::Status | |
685 | plt32(unsigned char *view, | |
686 | const Sized_relobj<32, big_endian>* object, | |
687 | const Symbol_value<32>* psymval, | |
688 | elfcpp::Elf_types<32>::Elf_Addr address, | |
689 | bool has_thumb_bit) | |
690 | { | |
691 | return arm_branch_common<elfcpp::R_ARM_PLT32>(view, object, psymval, | |
692 | address, has_thumb_bit); | |
693 | } | |
694 | ||
695 | // R_ARM_CALL: (S + A) | T - P | |
696 | static inline typename This::Status | |
697 | call(unsigned char *view, | |
698 | const Sized_relobj<32, big_endian>* object, | |
699 | const Symbol_value<32>* psymval, | |
700 | elfcpp::Elf_types<32>::Elf_Addr address, | |
701 | bool has_thumb_bit) | |
702 | { | |
703 | return arm_branch_common<elfcpp::R_ARM_CALL>(view, object, psymval, | |
704 | address, has_thumb_bit); | |
705 | } | |
706 | ||
707 | // R_ARM_JUMP24: (S + A) | T - P | |
708 | static inline typename This::Status | |
709 | jump24(unsigned char *view, | |
710 | const Sized_relobj<32, big_endian>* object, | |
711 | const Symbol_value<32>* psymval, | |
712 | elfcpp::Elf_types<32>::Elf_Addr address, | |
713 | bool has_thumb_bit) | |
714 | { | |
715 | return arm_branch_common<elfcpp::R_ARM_JUMP24>(view, object, psymval, | |
716 | address, has_thumb_bit); | |
717 | } | |
718 | ||
719 | // R_ARM_PREL: (S + A) | T - P | |
720 | static inline typename This::Status | |
721 | prel31(unsigned char *view, | |
722 | const Sized_relobj<32, big_endian>* object, | |
723 | const Symbol_value<32>* psymval, | |
724 | elfcpp::Elf_types<32>::Elf_Addr address, | |
725 | bool has_thumb_bit) | |
726 | { | |
727 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; | |
728 | Valtype* wv = reinterpret_cast<Valtype*>(view); | |
729 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); | |
730 | Valtype addend = utils::sign_extend<31>(val); | |
731 | Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit) | |
732 | - address); | |
733 | val = utils::bit_select(val, x, 0x7fffffffU); | |
734 | elfcpp::Swap<32, big_endian>::writeval(wv, val); | |
735 | return (utils::has_overflow<31>(x) ? | |
736 | This::STATUS_OVERFLOW : This::STATUS_OKAY); | |
737 | } | |
738 | }; | |
739 | ||
94cdfcff DK |
740 | // Get the GOT section, creating it if necessary. |
741 | ||
742 | template<bool big_endian> | |
743 | Output_data_got<32, big_endian>* | |
744 | Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout) | |
745 | { | |
746 | if (this->got_ == NULL) | |
747 | { | |
748 | gold_assert(symtab != NULL && layout != NULL); | |
749 | ||
750 | this->got_ = new Output_data_got<32, big_endian>(); | |
751 | ||
752 | Output_section* os; | |
753 | os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, | |
754 | (elfcpp::SHF_ALLOC | |
755 | | elfcpp::SHF_WRITE), | |
756 | this->got_); | |
757 | os->set_is_relro(); | |
758 | ||
759 | // The old GNU linker creates a .got.plt section. We just | |
760 | // create another set of data in the .got section. Note that we | |
761 | // always create a PLT if we create a GOT, although the PLT | |
762 | // might be empty. | |
763 | this->got_plt_ = new Output_data_space(4, "** GOT PLT"); | |
764 | os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, | |
765 | (elfcpp::SHF_ALLOC | |
766 | | elfcpp::SHF_WRITE), | |
767 | this->got_plt_); | |
768 | os->set_is_relro(); | |
769 | ||
770 | // The first three entries are reserved. | |
771 | this->got_plt_->set_current_data_size(3 * 4); | |
772 | ||
773 | // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. | |
774 | symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL, | |
775 | this->got_plt_, | |
776 | 0, 0, elfcpp::STT_OBJECT, | |
777 | elfcpp::STB_LOCAL, | |
778 | elfcpp::STV_HIDDEN, 0, | |
779 | false, false); | |
780 | } | |
781 | return this->got_; | |
782 | } | |
783 | ||
784 | // Get the dynamic reloc section, creating it if necessary. | |
785 | ||
786 | template<bool big_endian> | |
787 | typename Target_arm<big_endian>::Reloc_section* | |
788 | Target_arm<big_endian>::rel_dyn_section(Layout* layout) | |
789 | { | |
790 | if (this->rel_dyn_ == NULL) | |
791 | { | |
792 | gold_assert(layout != NULL); | |
793 | this->rel_dyn_ = new Reloc_section(parameters->options().combreloc()); | |
794 | layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL, | |
795 | elfcpp::SHF_ALLOC, this->rel_dyn_); | |
796 | } | |
797 | return this->rel_dyn_; | |
798 | } | |
799 | ||
800 | // A class to handle the PLT data. | |
801 | ||
802 | template<bool big_endian> | |
803 | class Output_data_plt_arm : public Output_section_data | |
804 | { | |
805 | public: | |
806 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian> | |
807 | Reloc_section; | |
808 | ||
809 | Output_data_plt_arm(Layout*, Output_data_space*); | |
810 | ||
811 | // Add an entry to the PLT. | |
812 | void | |
813 | add_entry(Symbol* gsym); | |
814 | ||
815 | // Return the .rel.plt section data. | |
816 | const Reloc_section* | |
817 | rel_plt() const | |
818 | { return this->rel_; } | |
819 | ||
820 | protected: | |
821 | void | |
822 | do_adjust_output_section(Output_section* os); | |
823 | ||
824 | // Write to a map file. | |
825 | void | |
826 | do_print_to_mapfile(Mapfile* mapfile) const | |
827 | { mapfile->print_output_data(this, _("** PLT")); } | |
828 | ||
829 | private: | |
830 | // Template for the first PLT entry. | |
831 | static const uint32_t first_plt_entry[5]; | |
832 | ||
833 | // Template for subsequent PLT entries. | |
834 | static const uint32_t plt_entry[3]; | |
835 | ||
836 | // Set the final size. | |
837 | void | |
838 | set_final_data_size() | |
839 | { | |
840 | this->set_data_size(sizeof(first_plt_entry) | |
841 | + this->count_ * sizeof(plt_entry)); | |
842 | } | |
843 | ||
844 | // Write out the PLT data. | |
845 | void | |
846 | do_write(Output_file*); | |
847 | ||
848 | // The reloc section. | |
849 | Reloc_section* rel_; | |
850 | // The .got.plt section. | |
851 | Output_data_space* got_plt_; | |
852 | // The number of PLT entries. | |
853 | unsigned int count_; | |
854 | }; | |
855 | ||
856 | // Create the PLT section. The ordinary .got section is an argument, | |
857 | // since we need to refer to the start. We also create our own .got | |
858 | // section just for PLT entries. | |
859 | ||
860 | template<bool big_endian> | |
861 | Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout, | |
862 | Output_data_space* got_plt) | |
863 | : Output_section_data(4), got_plt_(got_plt), count_(0) | |
864 | { | |
865 | this->rel_ = new Reloc_section(false); | |
866 | layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL, | |
867 | elfcpp::SHF_ALLOC, this->rel_); | |
868 | } | |
869 | ||
870 | template<bool big_endian> | |
871 | void | |
872 | Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os) | |
873 | { | |
874 | os->set_entsize(0); | |
875 | } | |
876 | ||
877 | // Add an entry to the PLT. | |
878 | ||
879 | template<bool big_endian> | |
880 | void | |
881 | Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym) | |
882 | { | |
883 | gold_assert(!gsym->has_plt_offset()); | |
884 | ||
885 | // Note that when setting the PLT offset we skip the initial | |
886 | // reserved PLT entry. | |
887 | gsym->set_plt_offset((this->count_) * sizeof(plt_entry) | |
888 | + sizeof(first_plt_entry)); | |
889 | ||
890 | ++this->count_; | |
891 | ||
892 | section_offset_type got_offset = this->got_plt_->current_data_size(); | |
893 | ||
894 | // Every PLT entry needs a GOT entry which points back to the PLT | |
895 | // entry (this will be changed by the dynamic linker, normally | |
896 | // lazily when the function is called). | |
897 | this->got_plt_->set_current_data_size(got_offset + 4); | |
898 | ||
899 | // Every PLT entry needs a reloc. | |
900 | gsym->set_needs_dynsym_entry(); | |
901 | this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_, | |
902 | got_offset); | |
903 | ||
904 | // Note that we don't need to save the symbol. The contents of the | |
905 | // PLT are independent of which symbols are used. The symbols only | |
906 | // appear in the relocations. | |
907 | } | |
908 | ||
909 | // ARM PLTs. | |
910 | // FIXME: This is not very flexible. Right now this has only been tested | |
911 | // on armv5te. If we are to support additional architecture features like | |
912 | // Thumb-2 or BE8, we need to make this more flexible like GNU ld. | |
913 | ||
914 | // The first entry in the PLT. | |
915 | template<bool big_endian> | |
916 | const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] = | |
917 | { | |
918 | 0xe52de004, // str lr, [sp, #-4]! | |
919 | 0xe59fe004, // ldr lr, [pc, #4] | |
920 | 0xe08fe00e, // add lr, pc, lr | |
921 | 0xe5bef008, // ldr pc, [lr, #8]! | |
922 | 0x00000000, // &GOT[0] - . | |
923 | }; | |
924 | ||
925 | // Subsequent entries in the PLT. | |
926 | ||
927 | template<bool big_endian> | |
928 | const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] = | |
929 | { | |
930 | 0xe28fc600, // add ip, pc, #0xNN00000 | |
931 | 0xe28cca00, // add ip, ip, #0xNN000 | |
932 | 0xe5bcf000, // ldr pc, [ip, #0xNNN]! | |
933 | }; | |
934 | ||
935 | // Write out the PLT. This uses the hand-coded instructions above, | |
936 | // and adjusts them as needed. This is all specified by the arm ELF | |
937 | // Processor Supplement. | |
938 | ||
939 | template<bool big_endian> | |
940 | void | |
941 | Output_data_plt_arm<big_endian>::do_write(Output_file* of) | |
942 | { | |
943 | const off_t offset = this->offset(); | |
944 | const section_size_type oview_size = | |
945 | convert_to_section_size_type(this->data_size()); | |
946 | unsigned char* const oview = of->get_output_view(offset, oview_size); | |
947 | ||
948 | const off_t got_file_offset = this->got_plt_->offset(); | |
949 | const section_size_type got_size = | |
950 | convert_to_section_size_type(this->got_plt_->data_size()); | |
951 | unsigned char* const got_view = of->get_output_view(got_file_offset, | |
952 | got_size); | |
953 | unsigned char* pov = oview; | |
954 | ||
955 | elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address(); | |
956 | elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address(); | |
957 | ||
958 | // Write first PLT entry. All but the last word are constants. | |
959 | const size_t num_first_plt_words = (sizeof(first_plt_entry) | |
960 | / sizeof(plt_entry[0])); | |
961 | for (size_t i = 0; i < num_first_plt_words - 1; i++) | |
962 | elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]); | |
963 | // Last word in first PLT entry is &GOT[0] - . | |
964 | elfcpp::Swap<32, big_endian>::writeval(pov + 16, | |
965 | got_address - (plt_address + 16)); | |
966 | pov += sizeof(first_plt_entry); | |
967 | ||
968 | unsigned char* got_pov = got_view; | |
969 | ||
970 | memset(got_pov, 0, 12); | |
971 | got_pov += 12; | |
972 | ||
973 | const int rel_size = elfcpp::Elf_sizes<32>::rel_size; | |
974 | unsigned int plt_offset = sizeof(first_plt_entry); | |
975 | unsigned int plt_rel_offset = 0; | |
976 | unsigned int got_offset = 12; | |
977 | const unsigned int count = this->count_; | |
978 | for (unsigned int i = 0; | |
979 | i < count; | |
980 | ++i, | |
981 | pov += sizeof(plt_entry), | |
982 | got_pov += 4, | |
983 | plt_offset += sizeof(plt_entry), | |
984 | plt_rel_offset += rel_size, | |
985 | got_offset += 4) | |
986 | { | |
987 | // Set and adjust the PLT entry itself. | |
988 | int32_t offset = ((got_address + got_offset) | |
989 | - (plt_address + plt_offset + 8)); | |
990 | ||
991 | gold_assert(offset >= 0 && offset < 0x0fffffff); | |
992 | uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff); | |
993 | elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0); | |
994 | uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff); | |
995 | elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1); | |
996 | uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff); | |
997 | elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2); | |
998 | ||
999 | // Set the entry in the GOT. | |
1000 | elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address); | |
1001 | } | |
1002 | ||
1003 | gold_assert(static_cast<section_size_type>(pov - oview) == oview_size); | |
1004 | gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size); | |
1005 | ||
1006 | of->write_output_view(offset, oview_size, oview); | |
1007 | of->write_output_view(got_file_offset, got_size, got_view); | |
1008 | } | |
1009 | ||
1010 | // Create a PLT entry for a global symbol. | |
1011 | ||
1012 | template<bool big_endian> | |
1013 | void | |
1014 | Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout, | |
1015 | Symbol* gsym) | |
1016 | { | |
1017 | if (gsym->has_plt_offset()) | |
1018 | return; | |
1019 | ||
1020 | if (this->plt_ == NULL) | |
1021 | { | |
1022 | // Create the GOT sections first. | |
1023 | this->got_section(symtab, layout); | |
1024 | ||
1025 | this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_); | |
1026 | layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS, | |
1027 | (elfcpp::SHF_ALLOC | |
1028 | | elfcpp::SHF_EXECINSTR), | |
1029 | this->plt_); | |
1030 | } | |
1031 | this->plt_->add_entry(gsym); | |
1032 | } | |
1033 | ||
4a657b0d DK |
1034 | // Report an unsupported relocation against a local symbol. |
1035 | ||
1036 | template<bool big_endian> | |
1037 | void | |
1038 | Target_arm<big_endian>::Scan::unsupported_reloc_local( | |
1039 | Sized_relobj<32, big_endian>* object, | |
1040 | unsigned int r_type) | |
1041 | { | |
1042 | gold_error(_("%s: unsupported reloc %u against local symbol"), | |
1043 | object->name().c_str(), r_type); | |
1044 | } | |
1045 | ||
bec53400 DK |
1046 | // We are about to emit a dynamic relocation of type R_TYPE. If the |
1047 | // dynamic linker does not support it, issue an error. The GNU linker | |
1048 | // only issues a non-PIC error for an allocated read-only section. | |
1049 | // Here we know the section is allocated, but we don't know that it is | |
1050 | // read-only. But we check for all the relocation types which the | |
1051 | // glibc dynamic linker supports, so it seems appropriate to issue an | |
1052 | // error even if the section is not read-only. | |
1053 | ||
1054 | template<bool big_endian> | |
1055 | void | |
1056 | Target_arm<big_endian>::Scan::check_non_pic(Relobj* object, | |
1057 | unsigned int r_type) | |
1058 | { | |
1059 | switch (r_type) | |
1060 | { | |
1061 | // These are the relocation types supported by glibc for ARM. | |
1062 | case elfcpp::R_ARM_RELATIVE: | |
1063 | case elfcpp::R_ARM_COPY: | |
1064 | case elfcpp::R_ARM_GLOB_DAT: | |
1065 | case elfcpp::R_ARM_JUMP_SLOT: | |
1066 | case elfcpp::R_ARM_ABS32: | |
1067 | case elfcpp::R_ARM_PC24: | |
1068 | // FIXME: The following 3 types are not supported by Android's dynamic | |
1069 | // linker. | |
1070 | case elfcpp::R_ARM_TLS_DTPMOD32: | |
1071 | case elfcpp::R_ARM_TLS_DTPOFF32: | |
1072 | case elfcpp::R_ARM_TLS_TPOFF32: | |
1073 | return; | |
1074 | ||
1075 | default: | |
1076 | // This prevents us from issuing more than one error per reloc | |
1077 | // section. But we can still wind up issuing more than one | |
1078 | // error per object file. | |
1079 | if (this->issued_non_pic_error_) | |
1080 | return; | |
1081 | object->error(_("requires unsupported dynamic reloc; " | |
1082 | "recompile with -fPIC")); | |
1083 | this->issued_non_pic_error_ = true; | |
1084 | return; | |
1085 | ||
1086 | case elfcpp::R_ARM_NONE: | |
1087 | gold_unreachable(); | |
1088 | } | |
1089 | } | |
1090 | ||
4a657b0d | 1091 | // Scan a relocation for a local symbol. |
bec53400 DK |
1092 | // FIXME: This only handles a subset of relocation types used by Android |
1093 | // on ARM v5te devices. | |
4a657b0d DK |
1094 | |
1095 | template<bool big_endian> | |
1096 | inline void | |
1097 | Target_arm<big_endian>::Scan::local(const General_options&, | |
bec53400 DK |
1098 | Symbol_table* symtab, |
1099 | Layout* layout, | |
1100 | Target_arm* target, | |
4a657b0d | 1101 | Sized_relobj<32, big_endian>* object, |
bec53400 DK |
1102 | unsigned int data_shndx, |
1103 | Output_section* output_section, | |
1104 | const elfcpp::Rel<32, big_endian>& reloc, | |
4a657b0d DK |
1105 | unsigned int r_type, |
1106 | const elfcpp::Sym<32, big_endian>&) | |
1107 | { | |
1108 | r_type = get_real_reloc_type(r_type); | |
1109 | switch (r_type) | |
1110 | { | |
1111 | case elfcpp::R_ARM_NONE: | |
1112 | break; | |
1113 | ||
5e445df6 ILT |
1114 | case elfcpp::R_ARM_ABS8: |
1115 | if (parameters->options().output_is_position_independent()) | |
1116 | { | |
1117 | // FIXME: Create a dynamic relocation for this location. | |
1118 | gold_error(_("%s: gold bug: need dynamic ABS8 reloc"), | |
1119 | object->name().c_str()); | |
1120 | } | |
1121 | break; | |
1122 | ||
bec53400 DK |
1123 | case elfcpp::R_ARM_ABS32: |
1124 | // If building a shared library (or a position-independent | |
1125 | // executable), we need to create a dynamic relocation for | |
1126 | // this location. The relocation applied at link time will | |
1127 | // apply the link-time value, so we flag the location with | |
1128 | // an R_ARM_RELATIVE relocation so the dynamic loader can | |
1129 | // relocate it easily. | |
1130 | if (parameters->options().output_is_position_independent()) | |
1131 | { | |
1132 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
1133 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); | |
1134 | // If we are to add more other reloc types than R_ARM_ABS32, | |
1135 | // we need to add check_non_pic(object, r_type) here. | |
1136 | rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE, | |
1137 | output_section, data_shndx, | |
1138 | reloc.get_r_offset()); | |
1139 | } | |
1140 | break; | |
1141 | ||
1142 | case elfcpp::R_ARM_REL32: | |
1143 | case elfcpp::R_ARM_THM_CALL: | |
1144 | case elfcpp::R_ARM_CALL: | |
1145 | case elfcpp::R_ARM_PREL31: | |
1146 | case elfcpp::R_ARM_JUMP24: | |
1147 | case elfcpp::R_ARM_PLT32: | |
1148 | break; | |
1149 | ||
1150 | case elfcpp::R_ARM_GOTOFF32: | |
1151 | // We need a GOT section: | |
1152 | target->got_section(symtab, layout); | |
1153 | break; | |
1154 | ||
1155 | case elfcpp::R_ARM_BASE_PREL: | |
1156 | // FIXME: What about this? | |
1157 | break; | |
1158 | ||
1159 | case elfcpp::R_ARM_GOT_BREL: | |
1160 | { | |
1161 | // The symbol requires a GOT entry. | |
1162 | Output_data_got<32, big_endian>* got = | |
1163 | target->got_section(symtab, layout); | |
1164 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); | |
1165 | if (got->add_local(object, r_sym, GOT_TYPE_STANDARD)) | |
1166 | { | |
1167 | // If we are generating a shared object, we need to add a | |
1168 | // dynamic RELATIVE relocation for this symbol's GOT entry. | |
1169 | if (parameters->options().output_is_position_independent()) | |
1170 | { | |
1171 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
1172 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); | |
1173 | rel_dyn->add_local_relative( | |
1174 | object, r_sym, elfcpp::R_ARM_RELATIVE, got, | |
1175 | object->local_got_offset(r_sym, GOT_TYPE_STANDARD)); | |
1176 | } | |
1177 | } | |
1178 | } | |
1179 | break; | |
1180 | ||
1181 | case elfcpp::R_ARM_TARGET1: | |
1182 | // This should have been mapped to another type already. | |
1183 | // Fall through. | |
1184 | case elfcpp::R_ARM_COPY: | |
1185 | case elfcpp::R_ARM_GLOB_DAT: | |
1186 | case elfcpp::R_ARM_JUMP_SLOT: | |
1187 | case elfcpp::R_ARM_RELATIVE: | |
1188 | // These are relocations which should only be seen by the | |
1189 | // dynamic linker, and should never be seen here. | |
1190 | gold_error(_("%s: unexpected reloc %u in object file"), | |
1191 | object->name().c_str(), r_type); | |
1192 | break; | |
1193 | ||
4a657b0d DK |
1194 | default: |
1195 | unsupported_reloc_local(object, r_type); | |
1196 | break; | |
1197 | } | |
1198 | } | |
1199 | ||
1200 | // Report an unsupported relocation against a global symbol. | |
1201 | ||
1202 | template<bool big_endian> | |
1203 | void | |
1204 | Target_arm<big_endian>::Scan::unsupported_reloc_global( | |
1205 | Sized_relobj<32, big_endian>* object, | |
1206 | unsigned int r_type, | |
1207 | Symbol* gsym) | |
1208 | { | |
1209 | gold_error(_("%s: unsupported reloc %u against global symbol %s"), | |
1210 | object->name().c_str(), r_type, gsym->demangled_name().c_str()); | |
1211 | } | |
1212 | ||
1213 | // Scan a relocation for a global symbol. | |
bec53400 DK |
1214 | // FIXME: This only handles a subset of relocation types used by Android |
1215 | // on ARM v5te devices. | |
4a657b0d DK |
1216 | |
1217 | template<bool big_endian> | |
1218 | inline void | |
1219 | Target_arm<big_endian>::Scan::global(const General_options&, | |
bec53400 DK |
1220 | Symbol_table* symtab, |
1221 | Layout* layout, | |
1222 | Target_arm* target, | |
4a657b0d | 1223 | Sized_relobj<32, big_endian>* object, |
bec53400 DK |
1224 | unsigned int data_shndx, |
1225 | Output_section* output_section, | |
1226 | const elfcpp::Rel<32, big_endian>& reloc, | |
4a657b0d DK |
1227 | unsigned int r_type, |
1228 | Symbol* gsym) | |
1229 | { | |
1230 | r_type = get_real_reloc_type(r_type); | |
1231 | switch (r_type) | |
1232 | { | |
1233 | case elfcpp::R_ARM_NONE: | |
1234 | break; | |
1235 | ||
5e445df6 ILT |
1236 | case elfcpp::R_ARM_ABS8: |
1237 | // Make a dynamic relocation if necessary. | |
1238 | if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF)) | |
1239 | { | |
1240 | // FIXME: Create a dynamic relocation for this location. | |
1241 | gold_error(_("%s: gold bug: need dynamic ABS8 reloc for %s"), | |
1242 | object->name().c_str(), gsym->demangled_name().c_str()); | |
1243 | } | |
1244 | break; | |
1245 | ||
bec53400 DK |
1246 | case elfcpp::R_ARM_ABS32: |
1247 | { | |
1248 | // Make a dynamic relocation if necessary. | |
1249 | if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF)) | |
1250 | { | |
1251 | if (target->may_need_copy_reloc(gsym)) | |
1252 | { | |
1253 | target->copy_reloc(symtab, layout, object, | |
1254 | data_shndx, output_section, gsym, reloc); | |
1255 | } | |
1256 | else if (gsym->can_use_relative_reloc(false)) | |
1257 | { | |
1258 | // If we are to add more other reloc types than R_ARM_ABS32, | |
1259 | // we need to add check_non_pic(object, r_type) here. | |
1260 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
1261 | rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE, | |
1262 | output_section, object, | |
1263 | data_shndx, reloc.get_r_offset()); | |
1264 | } | |
1265 | else | |
1266 | { | |
1267 | // If we are to add more other reloc types than R_ARM_ABS32, | |
1268 | // we need to add check_non_pic(object, r_type) here. | |
1269 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
1270 | rel_dyn->add_global(gsym, r_type, output_section, object, | |
1271 | data_shndx, reloc.get_r_offset()); | |
1272 | } | |
1273 | } | |
1274 | } | |
1275 | break; | |
1276 | ||
1277 | case elfcpp::R_ARM_REL32: | |
1278 | case elfcpp::R_ARM_PREL31: | |
1279 | { | |
1280 | // Make a dynamic relocation if necessary. | |
1281 | int flags = Symbol::NON_PIC_REF; | |
1282 | if (gsym->needs_dynamic_reloc(flags)) | |
1283 | { | |
1284 | if (target->may_need_copy_reloc(gsym)) | |
1285 | { | |
1286 | target->copy_reloc(symtab, layout, object, | |
1287 | data_shndx, output_section, gsym, reloc); | |
1288 | } | |
1289 | else | |
1290 | { | |
1291 | check_non_pic(object, r_type); | |
1292 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
1293 | rel_dyn->add_global(gsym, r_type, output_section, object, | |
1294 | data_shndx, reloc.get_r_offset()); | |
1295 | } | |
1296 | } | |
1297 | } | |
1298 | break; | |
1299 | ||
1300 | case elfcpp::R_ARM_JUMP24: | |
1301 | case elfcpp::R_ARM_THM_CALL: | |
1302 | case elfcpp::R_ARM_CALL: | |
1303 | { | |
1304 | if (Target_arm<big_endian>::Scan::symbol_needs_plt_entry(gsym)) | |
1305 | target->make_plt_entry(symtab, layout, gsym); | |
1306 | // Make a dynamic relocation if necessary. | |
1307 | int flags = Symbol::NON_PIC_REF; | |
1308 | if (gsym->type() == elfcpp::STT_FUNC | |
07800fab | 1309 | || gsym->type() == elfcpp::STT_ARM_TFUNC) |
bec53400 DK |
1310 | flags |= Symbol::FUNCTION_CALL; |
1311 | if (gsym->needs_dynamic_reloc(flags)) | |
1312 | { | |
1313 | if (target->may_need_copy_reloc(gsym)) | |
1314 | { | |
1315 | target->copy_reloc(symtab, layout, object, | |
1316 | data_shndx, output_section, gsym, | |
1317 | reloc); | |
1318 | } | |
1319 | else | |
1320 | { | |
1321 | check_non_pic(object, r_type); | |
1322 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
1323 | rel_dyn->add_global(gsym, r_type, output_section, object, | |
1324 | data_shndx, reloc.get_r_offset()); | |
1325 | } | |
1326 | } | |
1327 | } | |
1328 | break; | |
1329 | ||
1330 | case elfcpp::R_ARM_PLT32: | |
1331 | // If the symbol is fully resolved, this is just a relative | |
1332 | // local reloc. Otherwise we need a PLT entry. | |
1333 | if (gsym->final_value_is_known()) | |
1334 | break; | |
1335 | // If building a shared library, we can also skip the PLT entry | |
1336 | // if the symbol is defined in the output file and is protected | |
1337 | // or hidden. | |
1338 | if (gsym->is_defined() | |
1339 | && !gsym->is_from_dynobj() | |
1340 | && !gsym->is_preemptible()) | |
1341 | break; | |
1342 | target->make_plt_entry(symtab, layout, gsym); | |
1343 | break; | |
1344 | ||
1345 | case elfcpp::R_ARM_GOTOFF32: | |
1346 | // We need a GOT section. | |
1347 | target->got_section(symtab, layout); | |
1348 | break; | |
1349 | ||
1350 | case elfcpp::R_ARM_BASE_PREL: | |
1351 | // FIXME: What about this? | |
1352 | break; | |
1353 | ||
1354 | case elfcpp::R_ARM_GOT_BREL: | |
1355 | { | |
1356 | // The symbol requires a GOT entry. | |
1357 | Output_data_got<32, big_endian>* got = | |
1358 | target->got_section(symtab, layout); | |
1359 | if (gsym->final_value_is_known()) | |
1360 | got->add_global(gsym, GOT_TYPE_STANDARD); | |
1361 | else | |
1362 | { | |
1363 | // If this symbol is not fully resolved, we need to add a | |
1364 | // GOT entry with a dynamic relocation. | |
1365 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); | |
1366 | if (gsym->is_from_dynobj() | |
1367 | || gsym->is_undefined() | |
1368 | || gsym->is_preemptible()) | |
1369 | got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, | |
1370 | rel_dyn, elfcpp::R_ARM_GLOB_DAT); | |
1371 | else | |
1372 | { | |
1373 | if (got->add_global(gsym, GOT_TYPE_STANDARD)) | |
1374 | rel_dyn->add_global_relative( | |
1375 | gsym, elfcpp::R_ARM_RELATIVE, got, | |
1376 | gsym->got_offset(GOT_TYPE_STANDARD)); | |
1377 | } | |
1378 | } | |
1379 | } | |
1380 | break; | |
1381 | ||
1382 | case elfcpp::R_ARM_TARGET1: | |
1383 | // This should have been mapped to another type already. | |
1384 | // Fall through. | |
1385 | case elfcpp::R_ARM_COPY: | |
1386 | case elfcpp::R_ARM_GLOB_DAT: | |
1387 | case elfcpp::R_ARM_JUMP_SLOT: | |
1388 | case elfcpp::R_ARM_RELATIVE: | |
1389 | // These are relocations which should only be seen by the | |
1390 | // dynamic linker, and should never be seen here. | |
1391 | gold_error(_("%s: unexpected reloc %u in object file"), | |
1392 | object->name().c_str(), r_type); | |
1393 | break; | |
1394 | ||
4a657b0d DK |
1395 | default: |
1396 | unsupported_reloc_global(object, r_type, gsym); | |
1397 | break; | |
1398 | } | |
1399 | } | |
1400 | ||
1401 | // Process relocations for gc. | |
1402 | ||
1403 | template<bool big_endian> | |
1404 | void | |
1405 | Target_arm<big_endian>::gc_process_relocs(const General_options& options, | |
1406 | Symbol_table* symtab, | |
1407 | Layout* layout, | |
1408 | Sized_relobj<32, big_endian>* object, | |
1409 | unsigned int data_shndx, | |
1410 | unsigned int, | |
1411 | const unsigned char* prelocs, | |
1412 | size_t reloc_count, | |
1413 | Output_section* output_section, | |
1414 | bool needs_special_offset_handling, | |
1415 | size_t local_symbol_count, | |
1416 | const unsigned char* plocal_symbols) | |
1417 | { | |
1418 | typedef Target_arm<big_endian> Arm; | |
1419 | typedef typename Target_arm<big_endian>::Scan Scan; | |
1420 | ||
1421 | gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>( | |
1422 | options, | |
1423 | symtab, | |
1424 | layout, | |
1425 | this, | |
1426 | object, | |
1427 | data_shndx, | |
1428 | prelocs, | |
1429 | reloc_count, | |
1430 | output_section, | |
1431 | needs_special_offset_handling, | |
1432 | local_symbol_count, | |
1433 | plocal_symbols); | |
1434 | } | |
1435 | ||
1436 | // Scan relocations for a section. | |
1437 | ||
1438 | template<bool big_endian> | |
1439 | void | |
1440 | Target_arm<big_endian>::scan_relocs(const General_options& options, | |
1441 | Symbol_table* symtab, | |
1442 | Layout* layout, | |
1443 | Sized_relobj<32, big_endian>* object, | |
1444 | unsigned int data_shndx, | |
1445 | unsigned int sh_type, | |
1446 | const unsigned char* prelocs, | |
1447 | size_t reloc_count, | |
1448 | Output_section* output_section, | |
1449 | bool needs_special_offset_handling, | |
1450 | size_t local_symbol_count, | |
1451 | const unsigned char* plocal_symbols) | |
1452 | { | |
1453 | typedef typename Target_arm<big_endian>::Scan Scan; | |
1454 | if (sh_type == elfcpp::SHT_RELA) | |
1455 | { | |
1456 | gold_error(_("%s: unsupported RELA reloc section"), | |
1457 | object->name().c_str()); | |
1458 | return; | |
1459 | } | |
1460 | ||
1461 | gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>( | |
1462 | options, | |
1463 | symtab, | |
1464 | layout, | |
1465 | this, | |
1466 | object, | |
1467 | data_shndx, | |
1468 | prelocs, | |
1469 | reloc_count, | |
1470 | output_section, | |
1471 | needs_special_offset_handling, | |
1472 | local_symbol_count, | |
1473 | plocal_symbols); | |
1474 | } | |
1475 | ||
1476 | // Finalize the sections. | |
1477 | ||
1478 | template<bool big_endian> | |
1479 | void | |
94cdfcff | 1480 | Target_arm<big_endian>::do_finalize_sections(Layout* layout) |
4a657b0d | 1481 | { |
94cdfcff DK |
1482 | // Fill in some more dynamic tags. |
1483 | Output_data_dynamic* const odyn = layout->dynamic_data(); | |
1484 | if (odyn != NULL) | |
1485 | { | |
1486 | if (this->got_plt_ != NULL) | |
1487 | odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_); | |
1488 | ||
1489 | if (this->plt_ != NULL) | |
1490 | { | |
1491 | const Output_data* od = this->plt_->rel_plt(); | |
1492 | odyn->add_section_size(elfcpp::DT_PLTRELSZ, od); | |
1493 | odyn->add_section_address(elfcpp::DT_JMPREL, od); | |
1494 | odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL); | |
1495 | } | |
1496 | ||
1497 | if (this->rel_dyn_ != NULL) | |
1498 | { | |
1499 | const Output_data* od = this->rel_dyn_; | |
1500 | odyn->add_section_address(elfcpp::DT_REL, od); | |
1501 | odyn->add_section_size(elfcpp::DT_RELSZ, od); | |
1502 | odyn->add_constant(elfcpp::DT_RELENT, | |
1503 | elfcpp::Elf_sizes<32>::rel_size); | |
1504 | } | |
1505 | ||
1506 | if (!parameters->options().shared()) | |
1507 | { | |
1508 | // The value of the DT_DEBUG tag is filled in by the dynamic | |
1509 | // linker at run time, and used by the debugger. | |
1510 | odyn->add_constant(elfcpp::DT_DEBUG, 0); | |
1511 | } | |
1512 | } | |
1513 | ||
1514 | // Emit any relocs we saved in an attempt to avoid generating COPY | |
1515 | // relocs. | |
1516 | if (this->copy_relocs_.any_saved_relocs()) | |
1517 | this->copy_relocs_.emit(this->rel_dyn_section(layout)); | |
11af873f DK |
1518 | |
1519 | // For the ARM target, we need to add a PT_ARM_EXIDX segment for | |
1520 | // the .ARM.exidx section. | |
1521 | if (!layout->script_options()->saw_phdrs_clause() | |
1522 | && !parameters->options().relocatable()) | |
1523 | { | |
1524 | Output_section* exidx_section = | |
1525 | layout->find_output_section(".ARM.exidx"); | |
1526 | ||
1527 | if (exidx_section != NULL | |
1528 | && exidx_section->type() == elfcpp::SHT_ARM_EXIDX) | |
1529 | { | |
1530 | gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0) | |
1531 | == NULL); | |
1532 | Output_segment* exidx_segment = | |
1533 | layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R); | |
1534 | exidx_segment->add_output_section(exidx_section, elfcpp::PF_R); | |
1535 | } | |
1536 | } | |
4a657b0d DK |
1537 | } |
1538 | ||
bec53400 DK |
1539 | // Return whether a direct absolute static relocation needs to be applied. |
1540 | // In cases where Scan::local() or Scan::global() has created | |
1541 | // a dynamic relocation other than R_ARM_RELATIVE, the addend | |
1542 | // of the relocation is carried in the data, and we must not | |
1543 | // apply the static relocation. | |
1544 | ||
1545 | template<bool big_endian> | |
1546 | inline bool | |
1547 | Target_arm<big_endian>::Relocate::should_apply_static_reloc( | |
1548 | const Sized_symbol<32>* gsym, | |
1549 | int ref_flags, | |
1550 | bool is_32bit, | |
1551 | Output_section* output_section) | |
1552 | { | |
1553 | // If the output section is not allocated, then we didn't call | |
1554 | // scan_relocs, we didn't create a dynamic reloc, and we must apply | |
1555 | // the reloc here. | |
1556 | if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0) | |
1557 | return true; | |
1558 | ||
1559 | // For local symbols, we will have created a non-RELATIVE dynamic | |
1560 | // relocation only if (a) the output is position independent, | |
1561 | // (b) the relocation is absolute (not pc- or segment-relative), and | |
1562 | // (c) the relocation is not 32 bits wide. | |
1563 | if (gsym == NULL) | |
1564 | return !(parameters->options().output_is_position_independent() | |
1565 | && (ref_flags & Symbol::ABSOLUTE_REF) | |
1566 | && !is_32bit); | |
1567 | ||
1568 | // For global symbols, we use the same helper routines used in the | |
1569 | // scan pass. If we did not create a dynamic relocation, or if we | |
1570 | // created a RELATIVE dynamic relocation, we should apply the static | |
1571 | // relocation. | |
1572 | bool has_dyn = gsym->needs_dynamic_reloc(ref_flags); | |
1573 | bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF) | |
1574 | && gsym->can_use_relative_reloc(ref_flags | |
1575 | & Symbol::FUNCTION_CALL); | |
1576 | return !has_dyn || is_rel; | |
1577 | } | |
1578 | ||
4a657b0d DK |
1579 | // Perform a relocation. |
1580 | ||
1581 | template<bool big_endian> | |
1582 | inline bool | |
1583 | Target_arm<big_endian>::Relocate::relocate( | |
c121c671 DK |
1584 | const Relocate_info<32, big_endian>* relinfo, |
1585 | Target_arm* target, | |
1586 | Output_section *output_section, | |
1587 | size_t relnum, | |
1588 | const elfcpp::Rel<32, big_endian>& rel, | |
4a657b0d | 1589 | unsigned int r_type, |
c121c671 DK |
1590 | const Sized_symbol<32>* gsym, |
1591 | const Symbol_value<32>* psymval, | |
1592 | unsigned char* view, | |
1593 | elfcpp::Elf_types<32>::Elf_Addr address, | |
4a657b0d DK |
1594 | section_size_type /* view_size */ ) |
1595 | { | |
c121c671 DK |
1596 | typedef Arm_relocate_functions<big_endian> Arm_relocate_functions; |
1597 | ||
1598 | r_type = get_real_reloc_type(r_type); | |
1599 | ||
1600 | // If this the symbol may be a Thumb function, set thumb bit to 1. | |
1601 | bool has_thumb_bit = ((gsym != NULL) | |
1602 | && (gsym->type() == elfcpp::STT_FUNC | |
1603 | || gsym->type() == elfcpp::STT_ARM_TFUNC)); | |
1604 | ||
1605 | // Pick the value to use for symbols defined in shared objects. | |
1606 | Symbol_value<32> symval; | |
1607 | if (gsym != NULL | |
1608 | && gsym->use_plt_offset(reloc_is_non_pic(r_type))) | |
1609 | { | |
1610 | symval.set_output_value(target->plt_section()->address() | |
1611 | + gsym->plt_offset()); | |
1612 | psymval = &symval; | |
1613 | has_thumb_bit = 0; | |
1614 | } | |
1615 | ||
1616 | const Sized_relobj<32, big_endian>* object = relinfo->object; | |
1617 | ||
1618 | // Get the GOT offset if needed. | |
1619 | // The GOT pointer points to the end of the GOT section. | |
1620 | // We need to subtract the size of the GOT section to get | |
1621 | // the actual offset to use in the relocation. | |
1622 | bool have_got_offset = false; | |
1623 | unsigned int got_offset = 0; | |
1624 | switch (r_type) | |
1625 | { | |
1626 | case elfcpp::R_ARM_GOT_BREL: | |
1627 | if (gsym != NULL) | |
1628 | { | |
1629 | gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD)); | |
1630 | got_offset = (gsym->got_offset(GOT_TYPE_STANDARD) | |
1631 | - target->got_size()); | |
1632 | } | |
1633 | else | |
1634 | { | |
1635 | unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info()); | |
1636 | gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD)); | |
1637 | got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD) | |
1638 | - target->got_size()); | |
1639 | } | |
1640 | have_got_offset = true; | |
1641 | break; | |
1642 | ||
1643 | default: | |
1644 | break; | |
1645 | } | |
1646 | ||
1647 | typename Arm_relocate_functions::Status reloc_status = | |
1648 | Arm_relocate_functions::STATUS_OKAY; | |
4a657b0d DK |
1649 | switch (r_type) |
1650 | { | |
1651 | case elfcpp::R_ARM_NONE: | |
1652 | break; | |
1653 | ||
5e445df6 ILT |
1654 | case elfcpp::R_ARM_ABS8: |
1655 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, | |
1656 | output_section)) | |
1657 | reloc_status = Arm_relocate_functions::abs8(view, object, psymval, | |
1658 | has_thumb_bit); | |
1659 | break; | |
1660 | ||
c121c671 DK |
1661 | case elfcpp::R_ARM_ABS32: |
1662 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, | |
1663 | output_section)) | |
1664 | reloc_status = Arm_relocate_functions::abs32(view, object, psymval, | |
1665 | has_thumb_bit); | |
1666 | break; | |
1667 | ||
1668 | case elfcpp::R_ARM_REL32: | |
1669 | reloc_status = Arm_relocate_functions::rel32(view, object, psymval, | |
1670 | address, has_thumb_bit); | |
1671 | break; | |
1672 | ||
1673 | case elfcpp::R_ARM_THM_CALL: | |
1674 | reloc_status = Arm_relocate_functions::thm_call(view, object, psymval, | |
1675 | address, has_thumb_bit); | |
1676 | break; | |
1677 | ||
1678 | case elfcpp::R_ARM_GOTOFF32: | |
1679 | { | |
1680 | elfcpp::Elf_types<32>::Elf_Addr got_origin; | |
1681 | got_origin = target->got_plt_section()->address(); | |
1682 | reloc_status = Arm_relocate_functions::rel32(view, object, psymval, | |
1683 | got_origin, has_thumb_bit); | |
1684 | } | |
1685 | break; | |
1686 | ||
1687 | case elfcpp::R_ARM_BASE_PREL: | |
1688 | { | |
1689 | uint32_t origin; | |
1690 | // Get the addressing origin of the output segment defining the | |
1691 | // symbol gsym (AAELF 4.6.1.2 Relocation types) | |
1692 | gold_assert(gsym != NULL); | |
1693 | if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT) | |
1694 | origin = gsym->output_segment()->vaddr(); | |
1695 | else if (gsym->source () == Symbol::IN_OUTPUT_DATA) | |
1696 | origin = gsym->output_data()->address(); | |
1697 | else | |
1698 | { | |
1699 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), | |
1700 | _("cannot find origin of R_ARM_BASE_PREL")); | |
1701 | return true; | |
1702 | } | |
1703 | reloc_status = Arm_relocate_functions::base_prel(view, origin, address); | |
1704 | } | |
1705 | break; | |
1706 | ||
1707 | case elfcpp::R_ARM_GOT_BREL: | |
1708 | gold_assert(have_got_offset); | |
1709 | reloc_status = Arm_relocate_functions::got_brel(view, got_offset); | |
1710 | break; | |
1711 | ||
1712 | case elfcpp::R_ARM_PLT32: | |
1713 | gold_assert(gsym == NULL | |
1714 | || gsym->has_plt_offset() | |
1715 | || gsym->final_value_is_known() | |
1716 | || (gsym->is_defined() | |
1717 | && !gsym->is_from_dynobj() | |
1718 | && !gsym->is_preemptible())); | |
1719 | reloc_status = Arm_relocate_functions::plt32(view, object, psymval, | |
1720 | address, has_thumb_bit); | |
1721 | break; | |
1722 | ||
1723 | case elfcpp::R_ARM_CALL: | |
1724 | reloc_status = Arm_relocate_functions::call(view, object, psymval, | |
1725 | address, has_thumb_bit); | |
1726 | break; | |
1727 | ||
1728 | case elfcpp::R_ARM_JUMP24: | |
1729 | reloc_status = Arm_relocate_functions::jump24(view, object, psymval, | |
1730 | address, has_thumb_bit); | |
1731 | break; | |
1732 | ||
1733 | case elfcpp::R_ARM_PREL31: | |
1734 | reloc_status = Arm_relocate_functions::prel31(view, object, psymval, | |
1735 | address, has_thumb_bit); | |
1736 | break; | |
1737 | ||
1738 | case elfcpp::R_ARM_TARGET1: | |
1739 | // This should have been mapped to another type already. | |
1740 | // Fall through. | |
1741 | case elfcpp::R_ARM_COPY: | |
1742 | case elfcpp::R_ARM_GLOB_DAT: | |
1743 | case elfcpp::R_ARM_JUMP_SLOT: | |
1744 | case elfcpp::R_ARM_RELATIVE: | |
1745 | // These are relocations which should only be seen by the | |
1746 | // dynamic linker, and should never be seen here. | |
1747 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), | |
1748 | _("unexpected reloc %u in object file"), | |
1749 | r_type); | |
1750 | break; | |
1751 | ||
1752 | default: | |
1753 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), | |
1754 | _("unsupported reloc %u"), | |
1755 | r_type); | |
1756 | break; | |
1757 | } | |
1758 | ||
1759 | // Report any errors. | |
1760 | switch (reloc_status) | |
1761 | { | |
1762 | case Arm_relocate_functions::STATUS_OKAY: | |
1763 | break; | |
1764 | case Arm_relocate_functions::STATUS_OVERFLOW: | |
1765 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), | |
1766 | _("relocation overflow in relocation %u"), | |
1767 | r_type); | |
1768 | break; | |
1769 | case Arm_relocate_functions::STATUS_BAD_RELOC: | |
1770 | gold_error_at_location( | |
1771 | relinfo, | |
1772 | relnum, | |
1773 | rel.get_r_offset(), | |
1774 | _("unexpected opcode while processing relocation %u"), | |
1775 | r_type); | |
1776 | break; | |
4a657b0d DK |
1777 | default: |
1778 | gold_unreachable(); | |
1779 | } | |
1780 | ||
1781 | return true; | |
1782 | } | |
1783 | ||
1784 | // Relocate section data. | |
1785 | ||
1786 | template<bool big_endian> | |
1787 | void | |
1788 | Target_arm<big_endian>::relocate_section( | |
1789 | const Relocate_info<32, big_endian>* relinfo, | |
1790 | unsigned int sh_type, | |
1791 | const unsigned char* prelocs, | |
1792 | size_t reloc_count, | |
1793 | Output_section* output_section, | |
1794 | bool needs_special_offset_handling, | |
1795 | unsigned char* view, | |
1796 | elfcpp::Elf_types<32>::Elf_Addr address, | |
1797 | section_size_type view_size) | |
1798 | { | |
1799 | typedef typename Target_arm<big_endian>::Relocate Arm_relocate; | |
1800 | gold_assert(sh_type == elfcpp::SHT_REL); | |
1801 | ||
1802 | gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL, | |
1803 | Arm_relocate>( | |
1804 | relinfo, | |
1805 | this, | |
1806 | prelocs, | |
1807 | reloc_count, | |
1808 | output_section, | |
1809 | needs_special_offset_handling, | |
1810 | view, | |
1811 | address, | |
1812 | view_size); | |
1813 | } | |
1814 | ||
1815 | // Return the size of a relocation while scanning during a relocatable | |
1816 | // link. | |
1817 | ||
1818 | template<bool big_endian> | |
1819 | unsigned int | |
1820 | Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc( | |
1821 | unsigned int r_type, | |
1822 | Relobj* object) | |
1823 | { | |
1824 | r_type = get_real_reloc_type(r_type); | |
1825 | switch (r_type) | |
1826 | { | |
1827 | case elfcpp::R_ARM_NONE: | |
1828 | return 0; | |
1829 | ||
5e445df6 ILT |
1830 | case elfcpp::R_ARM_ABS8: |
1831 | return 1; | |
1832 | ||
4a657b0d DK |
1833 | case elfcpp::R_ARM_ABS32: |
1834 | case elfcpp::R_ARM_REL32: | |
1835 | case elfcpp::R_ARM_THM_CALL: | |
1836 | case elfcpp::R_ARM_GOTOFF32: | |
1837 | case elfcpp::R_ARM_BASE_PREL: | |
1838 | case elfcpp::R_ARM_GOT_BREL: | |
1839 | case elfcpp::R_ARM_PLT32: | |
1840 | case elfcpp::R_ARM_CALL: | |
1841 | case elfcpp::R_ARM_JUMP24: | |
1842 | case elfcpp::R_ARM_PREL31: | |
1843 | return 4; | |
1844 | ||
1845 | case elfcpp::R_ARM_TARGET1: | |
1846 | // This should have been mapped to another type already. | |
1847 | // Fall through. | |
1848 | case elfcpp::R_ARM_COPY: | |
1849 | case elfcpp::R_ARM_GLOB_DAT: | |
1850 | case elfcpp::R_ARM_JUMP_SLOT: | |
1851 | case elfcpp::R_ARM_RELATIVE: | |
1852 | // These are relocations which should only be seen by the | |
1853 | // dynamic linker, and should never be seen here. | |
1854 | gold_error(_("%s: unexpected reloc %u in object file"), | |
1855 | object->name().c_str(), r_type); | |
1856 | return 0; | |
1857 | ||
1858 | default: | |
1859 | object->error(_("unsupported reloc %u in object file"), r_type); | |
1860 | return 0; | |
1861 | } | |
1862 | } | |
1863 | ||
1864 | // Scan the relocs during a relocatable link. | |
1865 | ||
1866 | template<bool big_endian> | |
1867 | void | |
1868 | Target_arm<big_endian>::scan_relocatable_relocs( | |
1869 | const General_options& options, | |
1870 | Symbol_table* symtab, | |
1871 | Layout* layout, | |
1872 | Sized_relobj<32, big_endian>* object, | |
1873 | unsigned int data_shndx, | |
1874 | unsigned int sh_type, | |
1875 | const unsigned char* prelocs, | |
1876 | size_t reloc_count, | |
1877 | Output_section* output_section, | |
1878 | bool needs_special_offset_handling, | |
1879 | size_t local_symbol_count, | |
1880 | const unsigned char* plocal_symbols, | |
1881 | Relocatable_relocs* rr) | |
1882 | { | |
1883 | gold_assert(sh_type == elfcpp::SHT_REL); | |
1884 | ||
1885 | typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL, | |
1886 | Relocatable_size_for_reloc> Scan_relocatable_relocs; | |
1887 | ||
1888 | gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL, | |
1889 | Scan_relocatable_relocs>( | |
1890 | options, | |
1891 | symtab, | |
1892 | layout, | |
1893 | object, | |
1894 | data_shndx, | |
1895 | prelocs, | |
1896 | reloc_count, | |
1897 | output_section, | |
1898 | needs_special_offset_handling, | |
1899 | local_symbol_count, | |
1900 | plocal_symbols, | |
1901 | rr); | |
1902 | } | |
1903 | ||
1904 | // Relocate a section during a relocatable link. | |
1905 | ||
1906 | template<bool big_endian> | |
1907 | void | |
1908 | Target_arm<big_endian>::relocate_for_relocatable( | |
1909 | const Relocate_info<32, big_endian>* relinfo, | |
1910 | unsigned int sh_type, | |
1911 | const unsigned char* prelocs, | |
1912 | size_t reloc_count, | |
1913 | Output_section* output_section, | |
1914 | off_t offset_in_output_section, | |
1915 | const Relocatable_relocs* rr, | |
1916 | unsigned char* view, | |
1917 | elfcpp::Elf_types<32>::Elf_Addr view_address, | |
1918 | section_size_type view_size, | |
1919 | unsigned char* reloc_view, | |
1920 | section_size_type reloc_view_size) | |
1921 | { | |
1922 | gold_assert(sh_type == elfcpp::SHT_REL); | |
1923 | ||
1924 | gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>( | |
1925 | relinfo, | |
1926 | prelocs, | |
1927 | reloc_count, | |
1928 | output_section, | |
1929 | offset_in_output_section, | |
1930 | rr, | |
1931 | view, | |
1932 | view_address, | |
1933 | view_size, | |
1934 | reloc_view, | |
1935 | reloc_view_size); | |
1936 | } | |
1937 | ||
94cdfcff DK |
1938 | // Return the value to use for a dynamic symbol which requires special |
1939 | // treatment. This is how we support equality comparisons of function | |
1940 | // pointers across shared library boundaries, as described in the | |
1941 | // processor specific ABI supplement. | |
1942 | ||
4a657b0d DK |
1943 | template<bool big_endian> |
1944 | uint64_t | |
94cdfcff | 1945 | Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const |
4a657b0d | 1946 | { |
94cdfcff DK |
1947 | gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset()); |
1948 | return this->plt_section()->address() + gsym->plt_offset(); | |
4a657b0d DK |
1949 | } |
1950 | ||
1951 | // Map platform-specific relocs to real relocs | |
1952 | // | |
1953 | template<bool big_endian> | |
1954 | unsigned int | |
1955 | Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type) | |
1956 | { | |
1957 | switch (r_type) | |
1958 | { | |
1959 | case elfcpp::R_ARM_TARGET1: | |
1960 | // This is either R_ARM_ABS32 or R_ARM_REL32; | |
1961 | return elfcpp::R_ARM_ABS32; | |
1962 | ||
1963 | case elfcpp::R_ARM_TARGET2: | |
1964 | // This can be any reloc type but ususally is R_ARM_GOT_PREL | |
1965 | return elfcpp::R_ARM_GOT_PREL; | |
1966 | ||
1967 | default: | |
1968 | return r_type; | |
1969 | } | |
1970 | } | |
1971 | ||
1972 | // The selector for arm object files. | |
1973 | ||
1974 | template<bool big_endian> | |
1975 | class Target_selector_arm : public Target_selector | |
1976 | { | |
1977 | public: | |
1978 | Target_selector_arm() | |
1979 | : Target_selector(elfcpp::EM_ARM, 32, big_endian, | |
1980 | (big_endian ? "elf32-bigarm" : "elf32-littlearm")) | |
1981 | { } | |
1982 | ||
1983 | Target* | |
1984 | do_instantiate_target() | |
1985 | { return new Target_arm<big_endian>(); } | |
1986 | }; | |
1987 | ||
1988 | Target_selector_arm<false> target_selector_arm; | |
1989 | Target_selector_arm<true> target_selector_armbe; | |
1990 | ||
1991 | } // End anonymous namespace. |