| 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 | // This file also contains borrowed and adapted code from |
| 7 | // bfd/elf32-arm.c. |
| 8 | |
| 9 | // This file is part of gold. |
| 10 | |
| 11 | // This program is free software; you can redistribute it and/or modify |
| 12 | // it under the terms of the GNU General Public License as published by |
| 13 | // the Free Software Foundation; either version 3 of the License, or |
| 14 | // (at your option) any later version. |
| 15 | |
| 16 | // This program is distributed in the hope that it will be useful, |
| 17 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | // GNU General Public License for more details. |
| 20 | |
| 21 | // You should have received a copy of the GNU General Public License |
| 22 | // along with this program; if not, write to the Free Software |
| 23 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| 24 | // MA 02110-1301, USA. |
| 25 | |
| 26 | #include "gold.h" |
| 27 | |
| 28 | #include <cstring> |
| 29 | #include <limits> |
| 30 | #include <cstdio> |
| 31 | #include <string> |
| 32 | #include <algorithm> |
| 33 | #include <map> |
| 34 | #include <utility> |
| 35 | |
| 36 | #include "elfcpp.h" |
| 37 | #include "parameters.h" |
| 38 | #include "reloc.h" |
| 39 | #include "arm.h" |
| 40 | #include "object.h" |
| 41 | #include "symtab.h" |
| 42 | #include "layout.h" |
| 43 | #include "output.h" |
| 44 | #include "copy-relocs.h" |
| 45 | #include "target.h" |
| 46 | #include "target-reloc.h" |
| 47 | #include "target-select.h" |
| 48 | #include "tls.h" |
| 49 | #include "defstd.h" |
| 50 | #include "gc.h" |
| 51 | #include "attributes.h" |
| 52 | |
| 53 | namespace |
| 54 | { |
| 55 | |
| 56 | using namespace gold; |
| 57 | |
| 58 | template<bool big_endian> |
| 59 | class Output_data_plt_arm; |
| 60 | |
| 61 | template<bool big_endian> |
| 62 | class Stub_table; |
| 63 | |
| 64 | template<bool big_endian> |
| 65 | class Arm_input_section; |
| 66 | |
| 67 | template<bool big_endian> |
| 68 | class Arm_output_section; |
| 69 | |
| 70 | template<bool big_endian> |
| 71 | class Arm_relobj; |
| 72 | |
| 73 | template<bool big_endian> |
| 74 | class Target_arm; |
| 75 | |
| 76 | // For convenience. |
| 77 | typedef elfcpp::Elf_types<32>::Elf_Addr Arm_address; |
| 78 | |
| 79 | // Maximum branch offsets for ARM, THUMB and THUMB2. |
| 80 | const int32_t ARM_MAX_FWD_BRANCH_OFFSET = ((((1 << 23) - 1) << 2) + 8); |
| 81 | const int32_t ARM_MAX_BWD_BRANCH_OFFSET = ((-((1 << 23) << 2)) + 8); |
| 82 | const int32_t THM_MAX_FWD_BRANCH_OFFSET = ((1 << 22) -2 + 4); |
| 83 | const int32_t THM_MAX_BWD_BRANCH_OFFSET = (-(1 << 22) + 4); |
| 84 | const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4); |
| 85 | const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4); |
| 86 | |
| 87 | // The arm target class. |
| 88 | // |
| 89 | // This is a very simple port of gold for ARM-EABI. It is intended for |
| 90 | // supporting Android only for the time being. Only these relocation types |
| 91 | // are supported. |
| 92 | // |
| 93 | // R_ARM_NONE |
| 94 | // R_ARM_ABS32 |
| 95 | // R_ARM_ABS32_NOI |
| 96 | // R_ARM_ABS16 |
| 97 | // R_ARM_ABS12 |
| 98 | // R_ARM_ABS8 |
| 99 | // R_ARM_THM_ABS5 |
| 100 | // R_ARM_BASE_ABS |
| 101 | // R_ARM_REL32 |
| 102 | // R_ARM_THM_CALL |
| 103 | // R_ARM_COPY |
| 104 | // R_ARM_GLOB_DAT |
| 105 | // R_ARM_BASE_PREL |
| 106 | // R_ARM_JUMP_SLOT |
| 107 | // R_ARM_RELATIVE |
| 108 | // R_ARM_GOTOFF32 |
| 109 | // R_ARM_GOT_BREL |
| 110 | // R_ARM_GOT_PREL |
| 111 | // R_ARM_PLT32 |
| 112 | // R_ARM_CALL |
| 113 | // R_ARM_JUMP24 |
| 114 | // R_ARM_TARGET1 |
| 115 | // R_ARM_PREL31 |
| 116 | // R_ARM_ABS8 |
| 117 | // R_ARM_MOVW_ABS_NC |
| 118 | // R_ARM_MOVT_ABS |
| 119 | // R_ARM_THM_MOVW_ABS_NC |
| 120 | // R_ARM_THM_MOVT_ABS |
| 121 | // R_ARM_MOVW_PREL_NC |
| 122 | // R_ARM_MOVT_PREL |
| 123 | // R_ARM_THM_MOVW_PREL_NC |
| 124 | // R_ARM_THM_MOVT_PREL |
| 125 | // R_ARM_V4BX |
| 126 | // R_ARM_THM_JUMP6 |
| 127 | // R_ARM_THM_JUMP8 |
| 128 | // R_ARM_THM_JUMP11 |
| 129 | // |
| 130 | // TODOs: |
| 131 | // - Support more relocation types as needed. |
| 132 | // - Make PLTs more flexible for different architecture features like |
| 133 | // Thumb-2 and BE8. |
| 134 | // There are probably a lot more. |
| 135 | |
| 136 | // Instruction template class. This class is similar to the insn_sequence |
| 137 | // struct in bfd/elf32-arm.c. |
| 138 | |
| 139 | class Insn_template |
| 140 | { |
| 141 | public: |
| 142 | // Types of instruction templates. |
| 143 | enum Type |
| 144 | { |
| 145 | THUMB16_TYPE = 1, |
| 146 | // THUMB16_SPECIAL_TYPE is used by sub-classes of Stub for instruction |
| 147 | // templates with class-specific semantics. Currently this is used |
| 148 | // only by the Cortex_a8_stub class for handling condition codes in |
| 149 | // conditional branches. |
| 150 | THUMB16_SPECIAL_TYPE, |
| 151 | THUMB32_TYPE, |
| 152 | ARM_TYPE, |
| 153 | DATA_TYPE |
| 154 | }; |
| 155 | |
| 156 | // Factory methods to create instruction templates in different formats. |
| 157 | |
| 158 | static const Insn_template |
| 159 | thumb16_insn(uint32_t data) |
| 160 | { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); } |
| 161 | |
| 162 | // A Thumb conditional branch, in which the proper condition is inserted |
| 163 | // when we build the stub. |
| 164 | static const Insn_template |
| 165 | thumb16_bcond_insn(uint32_t data) |
| 166 | { return Insn_template(data, THUMB16_SPECIAL_TYPE, elfcpp::R_ARM_NONE, 1); } |
| 167 | |
| 168 | static const Insn_template |
| 169 | thumb32_insn(uint32_t data) |
| 170 | { return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_NONE, 0); } |
| 171 | |
| 172 | static const Insn_template |
| 173 | thumb32_b_insn(uint32_t data, int reloc_addend) |
| 174 | { |
| 175 | return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_THM_JUMP24, |
| 176 | reloc_addend); |
| 177 | } |
| 178 | |
| 179 | static const Insn_template |
| 180 | arm_insn(uint32_t data) |
| 181 | { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_NONE, 0); } |
| 182 | |
| 183 | static const Insn_template |
| 184 | arm_rel_insn(unsigned data, int reloc_addend) |
| 185 | { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_JUMP24, reloc_addend); } |
| 186 | |
| 187 | static const Insn_template |
| 188 | data_word(unsigned data, unsigned int r_type, int reloc_addend) |
| 189 | { return Insn_template(data, DATA_TYPE, r_type, reloc_addend); } |
| 190 | |
| 191 | // Accessors. This class is used for read-only objects so no modifiers |
| 192 | // are provided. |
| 193 | |
| 194 | uint32_t |
| 195 | data() const |
| 196 | { return this->data_; } |
| 197 | |
| 198 | // Return the instruction sequence type of this. |
| 199 | Type |
| 200 | type() const |
| 201 | { return this->type_; } |
| 202 | |
| 203 | // Return the ARM relocation type of this. |
| 204 | unsigned int |
| 205 | r_type() const |
| 206 | { return this->r_type_; } |
| 207 | |
| 208 | int32_t |
| 209 | reloc_addend() const |
| 210 | { return this->reloc_addend_; } |
| 211 | |
| 212 | // Return size of instruction template in bytes. |
| 213 | size_t |
| 214 | size() const; |
| 215 | |
| 216 | // Return byte-alignment of instruction template. |
| 217 | unsigned |
| 218 | alignment() const; |
| 219 | |
| 220 | private: |
| 221 | // We make the constructor private to ensure that only the factory |
| 222 | // methods are used. |
| 223 | inline |
| 224 | Insn_template(unsigned data, Type type, unsigned int r_type, int reloc_addend) |
| 225 | : data_(data), type_(type), r_type_(r_type), reloc_addend_(reloc_addend) |
| 226 | { } |
| 227 | |
| 228 | // Instruction specific data. This is used to store information like |
| 229 | // some of the instruction bits. |
| 230 | uint32_t data_; |
| 231 | // Instruction template type. |
| 232 | Type type_; |
| 233 | // Relocation type if there is a relocation or R_ARM_NONE otherwise. |
| 234 | unsigned int r_type_; |
| 235 | // Relocation addend. |
| 236 | int32_t reloc_addend_; |
| 237 | }; |
| 238 | |
| 239 | // Macro for generating code to stub types. One entry per long/short |
| 240 | // branch stub |
| 241 | |
| 242 | #define DEF_STUBS \ |
| 243 | DEF_STUB(long_branch_any_any) \ |
| 244 | DEF_STUB(long_branch_v4t_arm_thumb) \ |
| 245 | DEF_STUB(long_branch_thumb_only) \ |
| 246 | DEF_STUB(long_branch_v4t_thumb_thumb) \ |
| 247 | DEF_STUB(long_branch_v4t_thumb_arm) \ |
| 248 | DEF_STUB(short_branch_v4t_thumb_arm) \ |
| 249 | DEF_STUB(long_branch_any_arm_pic) \ |
| 250 | DEF_STUB(long_branch_any_thumb_pic) \ |
| 251 | DEF_STUB(long_branch_v4t_thumb_thumb_pic) \ |
| 252 | DEF_STUB(long_branch_v4t_arm_thumb_pic) \ |
| 253 | DEF_STUB(long_branch_v4t_thumb_arm_pic) \ |
| 254 | DEF_STUB(long_branch_thumb_only_pic) \ |
| 255 | DEF_STUB(a8_veneer_b_cond) \ |
| 256 | DEF_STUB(a8_veneer_b) \ |
| 257 | DEF_STUB(a8_veneer_bl) \ |
| 258 | DEF_STUB(a8_veneer_blx) \ |
| 259 | DEF_STUB(v4_veneer_bx) |
| 260 | |
| 261 | // Stub types. |
| 262 | |
| 263 | #define DEF_STUB(x) arm_stub_##x, |
| 264 | typedef enum |
| 265 | { |
| 266 | arm_stub_none, |
| 267 | DEF_STUBS |
| 268 | |
| 269 | // First reloc stub type. |
| 270 | arm_stub_reloc_first = arm_stub_long_branch_any_any, |
| 271 | // Last reloc stub type. |
| 272 | arm_stub_reloc_last = arm_stub_long_branch_thumb_only_pic, |
| 273 | |
| 274 | // First Cortex-A8 stub type. |
| 275 | arm_stub_cortex_a8_first = arm_stub_a8_veneer_b_cond, |
| 276 | // Last Cortex-A8 stub type. |
| 277 | arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx, |
| 278 | |
| 279 | // Last stub type. |
| 280 | arm_stub_type_last = arm_stub_v4_veneer_bx |
| 281 | } Stub_type; |
| 282 | #undef DEF_STUB |
| 283 | |
| 284 | // Stub template class. Templates are meant to be read-only objects. |
| 285 | // A stub template for a stub type contains all read-only attributes |
| 286 | // common to all stubs of the same type. |
| 287 | |
| 288 | class Stub_template |
| 289 | { |
| 290 | public: |
| 291 | Stub_template(Stub_type, const Insn_template*, size_t); |
| 292 | |
| 293 | ~Stub_template() |
| 294 | { } |
| 295 | |
| 296 | // Return stub type. |
| 297 | Stub_type |
| 298 | type() const |
| 299 | { return this->type_; } |
| 300 | |
| 301 | // Return an array of instruction templates. |
| 302 | const Insn_template* |
| 303 | insns() const |
| 304 | { return this->insns_; } |
| 305 | |
| 306 | // Return size of template in number of instructions. |
| 307 | size_t |
| 308 | insn_count() const |
| 309 | { return this->insn_count_; } |
| 310 | |
| 311 | // Return size of template in bytes. |
| 312 | size_t |
| 313 | size() const |
| 314 | { return this->size_; } |
| 315 | |
| 316 | // Return alignment of the stub template. |
| 317 | unsigned |
| 318 | alignment() const |
| 319 | { return this->alignment_; } |
| 320 | |
| 321 | // Return whether entry point is in thumb mode. |
| 322 | bool |
| 323 | entry_in_thumb_mode() const |
| 324 | { return this->entry_in_thumb_mode_; } |
| 325 | |
| 326 | // Return number of relocations in this template. |
| 327 | size_t |
| 328 | reloc_count() const |
| 329 | { return this->relocs_.size(); } |
| 330 | |
| 331 | // Return index of the I-th instruction with relocation. |
| 332 | size_t |
| 333 | reloc_insn_index(size_t i) const |
| 334 | { |
| 335 | gold_assert(i < this->relocs_.size()); |
| 336 | return this->relocs_[i].first; |
| 337 | } |
| 338 | |
| 339 | // Return the offset of the I-th instruction with relocation from the |
| 340 | // beginning of the stub. |
| 341 | section_size_type |
| 342 | reloc_offset(size_t i) const |
| 343 | { |
| 344 | gold_assert(i < this->relocs_.size()); |
| 345 | return this->relocs_[i].second; |
| 346 | } |
| 347 | |
| 348 | private: |
| 349 | // This contains information about an instruction template with a relocation |
| 350 | // and its offset from start of stub. |
| 351 | typedef std::pair<size_t, section_size_type> Reloc; |
| 352 | |
| 353 | // A Stub_template may not be copied. We want to share templates as much |
| 354 | // as possible. |
| 355 | Stub_template(const Stub_template&); |
| 356 | Stub_template& operator=(const Stub_template&); |
| 357 | |
| 358 | // Stub type. |
| 359 | Stub_type type_; |
| 360 | // Points to an array of Insn_templates. |
| 361 | const Insn_template* insns_; |
| 362 | // Number of Insn_templates in insns_[]. |
| 363 | size_t insn_count_; |
| 364 | // Size of templated instructions in bytes. |
| 365 | size_t size_; |
| 366 | // Alignment of templated instructions. |
| 367 | unsigned alignment_; |
| 368 | // Flag to indicate if entry is in thumb mode. |
| 369 | bool entry_in_thumb_mode_; |
| 370 | // A table of reloc instruction indices and offsets. We can find these by |
| 371 | // looking at the instruction templates but we pre-compute and then stash |
| 372 | // them here for speed. |
| 373 | std::vector<Reloc> relocs_; |
| 374 | }; |
| 375 | |
| 376 | // |
| 377 | // A class for code stubs. This is a base class for different type of |
| 378 | // stubs used in the ARM target. |
| 379 | // |
| 380 | |
| 381 | class Stub |
| 382 | { |
| 383 | private: |
| 384 | static const section_offset_type invalid_offset = |
| 385 | static_cast<section_offset_type>(-1); |
| 386 | |
| 387 | public: |
| 388 | Stub(const Stub_template* stub_template) |
| 389 | : stub_template_(stub_template), offset_(invalid_offset) |
| 390 | { } |
| 391 | |
| 392 | virtual |
| 393 | ~Stub() |
| 394 | { } |
| 395 | |
| 396 | // Return the stub template. |
| 397 | const Stub_template* |
| 398 | stub_template() const |
| 399 | { return this->stub_template_; } |
| 400 | |
| 401 | // Return offset of code stub from beginning of its containing stub table. |
| 402 | section_offset_type |
| 403 | offset() const |
| 404 | { |
| 405 | gold_assert(this->offset_ != invalid_offset); |
| 406 | return this->offset_; |
| 407 | } |
| 408 | |
| 409 | // Set offset of code stub from beginning of its containing stub table. |
| 410 | void |
| 411 | set_offset(section_offset_type offset) |
| 412 | { this->offset_ = offset; } |
| 413 | |
| 414 | // Return the relocation target address of the i-th relocation in the |
| 415 | // stub. This must be defined in a child class. |
| 416 | Arm_address |
| 417 | reloc_target(size_t i) |
| 418 | { return this->do_reloc_target(i); } |
| 419 | |
| 420 | // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written. |
| 421 | void |
| 422 | write(unsigned char* view, section_size_type view_size, bool big_endian) |
| 423 | { this->do_write(view, view_size, big_endian); } |
| 424 | |
| 425 | // Return the instruction for THUMB16_SPECIAL_TYPE instruction template |
| 426 | // for the i-th instruction. |
| 427 | uint16_t |
| 428 | thumb16_special(size_t i) |
| 429 | { return this->do_thumb16_special(i); } |
| 430 | |
| 431 | protected: |
| 432 | // This must be defined in the child class. |
| 433 | virtual Arm_address |
| 434 | do_reloc_target(size_t) = 0; |
| 435 | |
| 436 | // This may be overridden in the child class. |
| 437 | virtual void |
| 438 | do_write(unsigned char* view, section_size_type view_size, bool big_endian) |
| 439 | { |
| 440 | if (big_endian) |
| 441 | this->do_fixed_endian_write<true>(view, view_size); |
| 442 | else |
| 443 | this->do_fixed_endian_write<false>(view, view_size); |
| 444 | } |
| 445 | |
| 446 | // This must be overridden if a child class uses the THUMB16_SPECIAL_TYPE |
| 447 | // instruction template. |
| 448 | virtual uint16_t |
| 449 | do_thumb16_special(size_t) |
| 450 | { gold_unreachable(); } |
| 451 | |
| 452 | private: |
| 453 | // A template to implement do_write. |
| 454 | template<bool big_endian> |
| 455 | void inline |
| 456 | do_fixed_endian_write(unsigned char*, section_size_type); |
| 457 | |
| 458 | // Its template. |
| 459 | const Stub_template* stub_template_; |
| 460 | // Offset within the section of containing this stub. |
| 461 | section_offset_type offset_; |
| 462 | }; |
| 463 | |
| 464 | // Reloc stub class. These are stubs we use to fix up relocation because |
| 465 | // of limited branch ranges. |
| 466 | |
| 467 | class Reloc_stub : public Stub |
| 468 | { |
| 469 | public: |
| 470 | static const unsigned int invalid_index = static_cast<unsigned int>(-1); |
| 471 | // We assume we never jump to this address. |
| 472 | static const Arm_address invalid_address = static_cast<Arm_address>(-1); |
| 473 | |
| 474 | // Return destination address. |
| 475 | Arm_address |
| 476 | destination_address() const |
| 477 | { |
| 478 | gold_assert(this->destination_address_ != this->invalid_address); |
| 479 | return this->destination_address_; |
| 480 | } |
| 481 | |
| 482 | // Set destination address. |
| 483 | void |
| 484 | set_destination_address(Arm_address address) |
| 485 | { |
| 486 | gold_assert(address != this->invalid_address); |
| 487 | this->destination_address_ = address; |
| 488 | } |
| 489 | |
| 490 | // Reset destination address. |
| 491 | void |
| 492 | reset_destination_address() |
| 493 | { this->destination_address_ = this->invalid_address; } |
| 494 | |
| 495 | // Determine stub type for a branch of a relocation of R_TYPE going |
| 496 | // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set, |
| 497 | // the branch target is a thumb instruction. TARGET is used for look |
| 498 | // up ARM-specific linker settings. |
| 499 | static Stub_type |
| 500 | stub_type_for_reloc(unsigned int r_type, Arm_address branch_address, |
| 501 | Arm_address branch_target, bool target_is_thumb); |
| 502 | |
| 503 | // Reloc_stub key. A key is logically a triplet of a stub type, a symbol |
| 504 | // and an addend. Since we treat global and local symbol differently, we |
| 505 | // use a Symbol object for a global symbol and a object-index pair for |
| 506 | // a local symbol. |
| 507 | class Key |
| 508 | { |
| 509 | public: |
| 510 | // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and |
| 511 | // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL |
| 512 | // and R_SYM must not be invalid_index. |
| 513 | Key(Stub_type stub_type, const Symbol* symbol, const Relobj* relobj, |
| 514 | unsigned int r_sym, int32_t addend) |
| 515 | : stub_type_(stub_type), addend_(addend) |
| 516 | { |
| 517 | if (symbol != NULL) |
| 518 | { |
| 519 | this->r_sym_ = Reloc_stub::invalid_index; |
| 520 | this->u_.symbol = symbol; |
| 521 | } |
| 522 | else |
| 523 | { |
| 524 | gold_assert(relobj != NULL && r_sym != invalid_index); |
| 525 | this->r_sym_ = r_sym; |
| 526 | this->u_.relobj = relobj; |
| 527 | } |
| 528 | } |
| 529 | |
| 530 | ~Key() |
| 531 | { } |
| 532 | |
| 533 | // Accessors: Keys are meant to be read-only object so no modifiers are |
| 534 | // provided. |
| 535 | |
| 536 | // Return stub type. |
| 537 | Stub_type |
| 538 | stub_type() const |
| 539 | { return this->stub_type_; } |
| 540 | |
| 541 | // Return the local symbol index or invalid_index. |
| 542 | unsigned int |
| 543 | r_sym() const |
| 544 | { return this->r_sym_; } |
| 545 | |
| 546 | // Return the symbol if there is one. |
| 547 | const Symbol* |
| 548 | symbol() const |
| 549 | { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; } |
| 550 | |
| 551 | // Return the relobj if there is one. |
| 552 | const Relobj* |
| 553 | relobj() const |
| 554 | { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; } |
| 555 | |
| 556 | // Whether this equals to another key k. |
| 557 | bool |
| 558 | eq(const Key& k) const |
| 559 | { |
| 560 | return ((this->stub_type_ == k.stub_type_) |
| 561 | && (this->r_sym_ == k.r_sym_) |
| 562 | && ((this->r_sym_ != Reloc_stub::invalid_index) |
| 563 | ? (this->u_.relobj == k.u_.relobj) |
| 564 | : (this->u_.symbol == k.u_.symbol)) |
| 565 | && (this->addend_ == k.addend_)); |
| 566 | } |
| 567 | |
| 568 | // Return a hash value. |
| 569 | size_t |
| 570 | hash_value() const |
| 571 | { |
| 572 | return (this->stub_type_ |
| 573 | ^ this->r_sym_ |
| 574 | ^ gold::string_hash<char>( |
| 575 | (this->r_sym_ != Reloc_stub::invalid_index) |
| 576 | ? this->u_.relobj->name().c_str() |
| 577 | : this->u_.symbol->name()) |
| 578 | ^ this->addend_); |
| 579 | } |
| 580 | |
| 581 | // Functors for STL associative containers. |
| 582 | struct hash |
| 583 | { |
| 584 | size_t |
| 585 | operator()(const Key& k) const |
| 586 | { return k.hash_value(); } |
| 587 | }; |
| 588 | |
| 589 | struct equal_to |
| 590 | { |
| 591 | bool |
| 592 | operator()(const Key& k1, const Key& k2) const |
| 593 | { return k1.eq(k2); } |
| 594 | }; |
| 595 | |
| 596 | // Name of key. This is mainly for debugging. |
| 597 | std::string |
| 598 | name() const; |
| 599 | |
| 600 | private: |
| 601 | // Stub type. |
| 602 | Stub_type stub_type_; |
| 603 | // If this is a local symbol, this is the index in the defining object. |
| 604 | // Otherwise, it is invalid_index for a global symbol. |
| 605 | unsigned int r_sym_; |
| 606 | // If r_sym_ is invalid index. This points to a global symbol. |
| 607 | // Otherwise, this points a relobj. We used the unsized and target |
| 608 | // independent Symbol and Relobj classes instead of Sized_symbol<32> and |
| 609 | // Arm_relobj. This is done to avoid making the stub class a template |
| 610 | // as most of the stub machinery is endianity-neutral. However, it |
| 611 | // may require a bit of casting done by users of this class. |
| 612 | union |
| 613 | { |
| 614 | const Symbol* symbol; |
| 615 | const Relobj* relobj; |
| 616 | } u_; |
| 617 | // Addend associated with a reloc. |
| 618 | int32_t addend_; |
| 619 | }; |
| 620 | |
| 621 | protected: |
| 622 | // Reloc_stubs are created via a stub factory. So these are protected. |
| 623 | Reloc_stub(const Stub_template* stub_template) |
| 624 | : Stub(stub_template), destination_address_(invalid_address) |
| 625 | { } |
| 626 | |
| 627 | ~Reloc_stub() |
| 628 | { } |
| 629 | |
| 630 | friend class Stub_factory; |
| 631 | |
| 632 | // Return the relocation target address of the i-th relocation in the |
| 633 | // stub. |
| 634 | Arm_address |
| 635 | do_reloc_target(size_t i) |
| 636 | { |
| 637 | // All reloc stub have only one relocation. |
| 638 | gold_assert(i == 0); |
| 639 | return this->destination_address_; |
| 640 | } |
| 641 | |
| 642 | private: |
| 643 | // Address of destination. |
| 644 | Arm_address destination_address_; |
| 645 | }; |
| 646 | |
| 647 | // Cortex-A8 stub class. We need a Cortex-A8 stub to redirect any 32-bit |
| 648 | // THUMB branch that meets the following conditions: |
| 649 | // |
| 650 | // 1. The branch straddles across a page boundary. i.e. lower 12-bit of |
| 651 | // branch address is 0xffe. |
| 652 | // 2. The branch target address is in the same page as the first word of the |
| 653 | // branch. |
| 654 | // 3. The branch follows a 32-bit instruction which is not a branch. |
| 655 | // |
| 656 | // To do the fix up, we need to store the address of the branch instruction |
| 657 | // and its target at least. We also need to store the original branch |
| 658 | // instruction bits for the condition code in a conditional branch. The |
| 659 | // condition code is used in a special instruction template. We also want |
| 660 | // to identify input sections needing Cortex-A8 workaround quickly. We store |
| 661 | // extra information about object and section index of the code section |
| 662 | // containing a branch being fixed up. The information is used to mark |
| 663 | // the code section when we finalize the Cortex-A8 stubs. |
| 664 | // |
| 665 | |
| 666 | class Cortex_a8_stub : public Stub |
| 667 | { |
| 668 | public: |
| 669 | ~Cortex_a8_stub() |
| 670 | { } |
| 671 | |
| 672 | // Return the object of the code section containing the branch being fixed |
| 673 | // up. |
| 674 | Relobj* |
| 675 | relobj() const |
| 676 | { return this->relobj_; } |
| 677 | |
| 678 | // Return the section index of the code section containing the branch being |
| 679 | // fixed up. |
| 680 | unsigned int |
| 681 | shndx() const |
| 682 | { return this->shndx_; } |
| 683 | |
| 684 | // Return the source address of stub. This is the address of the original |
| 685 | // branch instruction. LSB is 1 always set to indicate that it is a THUMB |
| 686 | // instruction. |
| 687 | Arm_address |
| 688 | source_address() const |
| 689 | { return this->source_address_; } |
| 690 | |
| 691 | // Return the destination address of the stub. This is the branch taken |
| 692 | // address of the original branch instruction. LSB is 1 if it is a THUMB |
| 693 | // instruction address. |
| 694 | Arm_address |
| 695 | destination_address() const |
| 696 | { return this->destination_address_; } |
| 697 | |
| 698 | // Return the instruction being fixed up. |
| 699 | uint32_t |
| 700 | original_insn() const |
| 701 | { return this->original_insn_; } |
| 702 | |
| 703 | protected: |
| 704 | // Cortex_a8_stubs are created via a stub factory. So these are protected. |
| 705 | Cortex_a8_stub(const Stub_template* stub_template, Relobj* relobj, |
| 706 | unsigned int shndx, Arm_address source_address, |
| 707 | Arm_address destination_address, uint32_t original_insn) |
| 708 | : Stub(stub_template), relobj_(relobj), shndx_(shndx), |
| 709 | source_address_(source_address | 1U), |
| 710 | destination_address_(destination_address), |
| 711 | original_insn_(original_insn) |
| 712 | { } |
| 713 | |
| 714 | friend class Stub_factory; |
| 715 | |
| 716 | // Return the relocation target address of the i-th relocation in the |
| 717 | // stub. |
| 718 | Arm_address |
| 719 | do_reloc_target(size_t i) |
| 720 | { |
| 721 | if (this->stub_template()->type() == arm_stub_a8_veneer_b_cond) |
| 722 | { |
| 723 | // The conditional branch veneer has two relocations. |
| 724 | gold_assert(i < 2); |
| 725 | return i == 0 ? this->source_address_ + 4 : this->destination_address_; |
| 726 | } |
| 727 | else |
| 728 | { |
| 729 | // All other Cortex-A8 stubs have only one relocation. |
| 730 | gold_assert(i == 0); |
| 731 | return this->destination_address_; |
| 732 | } |
| 733 | } |
| 734 | |
| 735 | // Return an instruction for the THUMB16_SPECIAL_TYPE instruction template. |
| 736 | uint16_t |
| 737 | do_thumb16_special(size_t); |
| 738 | |
| 739 | private: |
| 740 | // Object of the code section containing the branch being fixed up. |
| 741 | Relobj* relobj_; |
| 742 | // Section index of the code section containing the branch begin fixed up. |
| 743 | unsigned int shndx_; |
| 744 | // Source address of original branch. |
| 745 | Arm_address source_address_; |
| 746 | // Destination address of the original branch. |
| 747 | Arm_address destination_address_; |
| 748 | // Original branch instruction. This is needed for copying the condition |
| 749 | // code from a condition branch to its stub. |
| 750 | uint32_t original_insn_; |
| 751 | }; |
| 752 | |
| 753 | // ARMv4 BX Rx branch relocation stub class. |
| 754 | class Arm_v4bx_stub : public Stub |
| 755 | { |
| 756 | public: |
| 757 | ~Arm_v4bx_stub() |
| 758 | { } |
| 759 | |
| 760 | // Return the associated register. |
| 761 | uint32_t |
| 762 | reg() const |
| 763 | { return this->reg_; } |
| 764 | |
| 765 | protected: |
| 766 | // Arm V4BX stubs are created via a stub factory. So these are protected. |
| 767 | Arm_v4bx_stub(const Stub_template* stub_template, const uint32_t reg) |
| 768 | : Stub(stub_template), reg_(reg) |
| 769 | { } |
| 770 | |
| 771 | friend class Stub_factory; |
| 772 | |
| 773 | // Return the relocation target address of the i-th relocation in the |
| 774 | // stub. |
| 775 | Arm_address |
| 776 | do_reloc_target(size_t) |
| 777 | { gold_unreachable(); } |
| 778 | |
| 779 | // This may be overridden in the child class. |
| 780 | virtual void |
| 781 | do_write(unsigned char* view, section_size_type view_size, bool big_endian) |
| 782 | { |
| 783 | if (big_endian) |
| 784 | this->do_fixed_endian_v4bx_write<true>(view, view_size); |
| 785 | else |
| 786 | this->do_fixed_endian_v4bx_write<false>(view, view_size); |
| 787 | } |
| 788 | |
| 789 | private: |
| 790 | // A template to implement do_write. |
| 791 | template<bool big_endian> |
| 792 | void inline |
| 793 | do_fixed_endian_v4bx_write(unsigned char* view, section_size_type) |
| 794 | { |
| 795 | const Insn_template* insns = this->stub_template()->insns(); |
| 796 | elfcpp::Swap<32, big_endian>::writeval(view, |
| 797 | (insns[0].data() |
| 798 | + (this->reg_ << 16))); |
| 799 | view += insns[0].size(); |
| 800 | elfcpp::Swap<32, big_endian>::writeval(view, |
| 801 | (insns[1].data() + this->reg_)); |
| 802 | view += insns[1].size(); |
| 803 | elfcpp::Swap<32, big_endian>::writeval(view, |
| 804 | (insns[2].data() + this->reg_)); |
| 805 | } |
| 806 | |
| 807 | // A register index (r0-r14), which is associated with the stub. |
| 808 | uint32_t reg_; |
| 809 | }; |
| 810 | |
| 811 | // Stub factory class. |
| 812 | |
| 813 | class Stub_factory |
| 814 | { |
| 815 | public: |
| 816 | // Return the unique instance of this class. |
| 817 | static const Stub_factory& |
| 818 | get_instance() |
| 819 | { |
| 820 | static Stub_factory singleton; |
| 821 | return singleton; |
| 822 | } |
| 823 | |
| 824 | // Make a relocation stub. |
| 825 | Reloc_stub* |
| 826 | make_reloc_stub(Stub_type stub_type) const |
| 827 | { |
| 828 | gold_assert(stub_type >= arm_stub_reloc_first |
| 829 | && stub_type <= arm_stub_reloc_last); |
| 830 | return new Reloc_stub(this->stub_templates_[stub_type]); |
| 831 | } |
| 832 | |
| 833 | // Make a Cortex-A8 stub. |
| 834 | Cortex_a8_stub* |
| 835 | make_cortex_a8_stub(Stub_type stub_type, Relobj* relobj, unsigned int shndx, |
| 836 | Arm_address source, Arm_address destination, |
| 837 | uint32_t original_insn) const |
| 838 | { |
| 839 | gold_assert(stub_type >= arm_stub_cortex_a8_first |
| 840 | && stub_type <= arm_stub_cortex_a8_last); |
| 841 | return new Cortex_a8_stub(this->stub_templates_[stub_type], relobj, shndx, |
| 842 | source, destination, original_insn); |
| 843 | } |
| 844 | |
| 845 | // Make an ARM V4BX relocation stub. |
| 846 | // This method creates a stub from the arm_stub_v4_veneer_bx template only. |
| 847 | Arm_v4bx_stub* |
| 848 | make_arm_v4bx_stub(uint32_t reg) const |
| 849 | { |
| 850 | gold_assert(reg < 0xf); |
| 851 | return new Arm_v4bx_stub(this->stub_templates_[arm_stub_v4_veneer_bx], |
| 852 | reg); |
| 853 | } |
| 854 | |
| 855 | private: |
| 856 | // Constructor and destructor are protected since we only return a single |
| 857 | // instance created in Stub_factory::get_instance(). |
| 858 | |
| 859 | Stub_factory(); |
| 860 | |
| 861 | // A Stub_factory may not be copied since it is a singleton. |
| 862 | Stub_factory(const Stub_factory&); |
| 863 | Stub_factory& operator=(Stub_factory&); |
| 864 | |
| 865 | // Stub templates. These are initialized in the constructor. |
| 866 | const Stub_template* stub_templates_[arm_stub_type_last+1]; |
| 867 | }; |
| 868 | |
| 869 | // A class to hold stubs for the ARM target. |
| 870 | |
| 871 | template<bool big_endian> |
| 872 | class Stub_table : public Output_data |
| 873 | { |
| 874 | public: |
| 875 | Stub_table(Arm_input_section<big_endian>* owner) |
| 876 | : Output_data(), owner_(owner), reloc_stubs_(), cortex_a8_stubs_(), |
| 877 | arm_v4bx_stubs_(0xf), prev_data_size_(0), prev_addralign_(1) |
| 878 | { } |
| 879 | |
| 880 | ~Stub_table() |
| 881 | { } |
| 882 | |
| 883 | // Owner of this stub table. |
| 884 | Arm_input_section<big_endian>* |
| 885 | owner() const |
| 886 | { return this->owner_; } |
| 887 | |
| 888 | // Whether this stub table is empty. |
| 889 | bool |
| 890 | empty() const |
| 891 | { |
| 892 | return (this->reloc_stubs_.empty() |
| 893 | && this->cortex_a8_stubs_.empty() |
| 894 | && this->arm_v4bx_stubs_.empty()); |
| 895 | } |
| 896 | |
| 897 | // Return the current data size. |
| 898 | off_t |
| 899 | current_data_size() const |
| 900 | { return this->current_data_size_for_child(); } |
| 901 | |
| 902 | // Add a STUB with using KEY. Caller is reponsible for avoid adding |
| 903 | // if already a STUB with the same key has been added. |
| 904 | void |
| 905 | add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key) |
| 906 | { |
| 907 | const Stub_template* stub_template = stub->stub_template(); |
| 908 | gold_assert(stub_template->type() == key.stub_type()); |
| 909 | this->reloc_stubs_[key] = stub; |
| 910 | } |
| 911 | |
| 912 | // Add a Cortex-A8 STUB that fixes up a THUMB branch at ADDRESS. |
| 913 | // Caller is reponsible for avoid adding if already a STUB with the same |
| 914 | // address has been added. |
| 915 | void |
| 916 | add_cortex_a8_stub(Arm_address address, Cortex_a8_stub* stub) |
| 917 | { |
| 918 | std::pair<Arm_address, Cortex_a8_stub*> value(address, stub); |
| 919 | this->cortex_a8_stubs_.insert(value); |
| 920 | } |
| 921 | |
| 922 | // Add an ARM V4BX relocation stub. A register index will be retrieved |
| 923 | // from the stub. |
| 924 | void |
| 925 | add_arm_v4bx_stub(Arm_v4bx_stub* stub) |
| 926 | { |
| 927 | gold_assert(stub != NULL && this->arm_v4bx_stubs_[stub->reg()] == NULL); |
| 928 | this->arm_v4bx_stubs_[stub->reg()] = stub; |
| 929 | } |
| 930 | |
| 931 | // Remove all Cortex-A8 stubs. |
| 932 | void |
| 933 | remove_all_cortex_a8_stubs(); |
| 934 | |
| 935 | // Look up a relocation stub using KEY. Return NULL if there is none. |
| 936 | Reloc_stub* |
| 937 | find_reloc_stub(const Reloc_stub::Key& key) const |
| 938 | { |
| 939 | typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key); |
| 940 | return (p != this->reloc_stubs_.end()) ? p->second : NULL; |
| 941 | } |
| 942 | |
| 943 | // Look up an arm v4bx relocation stub using the register index. |
| 944 | // Return NULL if there is none. |
| 945 | Arm_v4bx_stub* |
| 946 | find_arm_v4bx_stub(const uint32_t reg) const |
| 947 | { |
| 948 | gold_assert(reg < 0xf); |
| 949 | return this->arm_v4bx_stubs_[reg]; |
| 950 | } |
| 951 | |
| 952 | // Relocate stubs in this stub table. |
| 953 | void |
| 954 | relocate_stubs(const Relocate_info<32, big_endian>*, |
| 955 | Target_arm<big_endian>*, Output_section*, |
| 956 | unsigned char*, Arm_address, section_size_type); |
| 957 | |
| 958 | // Update data size and alignment at the end of a relaxation pass. Return |
| 959 | // true if either data size or alignment is different from that of the |
| 960 | // previous relaxation pass. |
| 961 | bool |
| 962 | update_data_size_and_addralign(); |
| 963 | |
| 964 | // Finalize stubs. Set the offsets of all stubs and mark input sections |
| 965 | // needing the Cortex-A8 workaround. |
| 966 | void |
| 967 | finalize_stubs(); |
| 968 | |
| 969 | // Apply Cortex-A8 workaround to an address range. |
| 970 | void |
| 971 | apply_cortex_a8_workaround_to_address_range(Target_arm<big_endian>*, |
| 972 | unsigned char*, Arm_address, |
| 973 | section_size_type); |
| 974 | |
| 975 | protected: |
| 976 | // Write out section contents. |
| 977 | void |
| 978 | do_write(Output_file*); |
| 979 | |
| 980 | // Return the required alignment. |
| 981 | uint64_t |
| 982 | do_addralign() const |
| 983 | { return this->prev_addralign_; } |
| 984 | |
| 985 | // Reset address and file offset. |
| 986 | void |
| 987 | do_reset_address_and_file_offset() |
| 988 | { this->set_current_data_size_for_child(this->prev_data_size_); } |
| 989 | |
| 990 | // Set final data size. |
| 991 | void |
| 992 | set_final_data_size() |
| 993 | { this->set_data_size(this->current_data_size()); } |
| 994 | |
| 995 | private: |
| 996 | // Relocate one stub. |
| 997 | void |
| 998 | relocate_stub(Stub*, const Relocate_info<32, big_endian>*, |
| 999 | Target_arm<big_endian>*, Output_section*, |
| 1000 | unsigned char*, Arm_address, section_size_type); |
| 1001 | |
| 1002 | // Unordered map of relocation stubs. |
| 1003 | typedef |
| 1004 | Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash, |
| 1005 | Reloc_stub::Key::equal_to> |
| 1006 | Reloc_stub_map; |
| 1007 | |
| 1008 | // List of Cortex-A8 stubs ordered by addresses of branches being |
| 1009 | // fixed up in output. |
| 1010 | typedef std::map<Arm_address, Cortex_a8_stub*> Cortex_a8_stub_list; |
| 1011 | // List of Arm V4BX relocation stubs ordered by associated registers. |
| 1012 | typedef std::vector<Arm_v4bx_stub*> Arm_v4bx_stub_list; |
| 1013 | |
| 1014 | // Owner of this stub table. |
| 1015 | Arm_input_section<big_endian>* owner_; |
| 1016 | // The relocation stubs. |
| 1017 | Reloc_stub_map reloc_stubs_; |
| 1018 | // The cortex_a8_stubs. |
| 1019 | Cortex_a8_stub_list cortex_a8_stubs_; |
| 1020 | // The Arm V4BX relocation stubs. |
| 1021 | Arm_v4bx_stub_list arm_v4bx_stubs_; |
| 1022 | // data size of this in the previous pass. |
| 1023 | off_t prev_data_size_; |
| 1024 | // address alignment of this in the previous pass. |
| 1025 | uint64_t prev_addralign_; |
| 1026 | }; |
| 1027 | |
| 1028 | // A class to wrap an ordinary input section containing executable code. |
| 1029 | |
| 1030 | template<bool big_endian> |
| 1031 | class Arm_input_section : public Output_relaxed_input_section |
| 1032 | { |
| 1033 | public: |
| 1034 | Arm_input_section(Relobj* relobj, unsigned int shndx) |
| 1035 | : Output_relaxed_input_section(relobj, shndx, 1), |
| 1036 | original_addralign_(1), original_size_(0), stub_table_(NULL) |
| 1037 | { } |
| 1038 | |
| 1039 | ~Arm_input_section() |
| 1040 | { } |
| 1041 | |
| 1042 | // Initialize. |
| 1043 | void |
| 1044 | init(); |
| 1045 | |
| 1046 | // Whether this is a stub table owner. |
| 1047 | bool |
| 1048 | is_stub_table_owner() const |
| 1049 | { return this->stub_table_ != NULL && this->stub_table_->owner() == this; } |
| 1050 | |
| 1051 | // Return the stub table. |
| 1052 | Stub_table<big_endian>* |
| 1053 | stub_table() const |
| 1054 | { return this->stub_table_; } |
| 1055 | |
| 1056 | // Set the stub_table. |
| 1057 | void |
| 1058 | set_stub_table(Stub_table<big_endian>* stub_table) |
| 1059 | { this->stub_table_ = stub_table; } |
| 1060 | |
| 1061 | // Downcast a base pointer to an Arm_input_section pointer. This is |
| 1062 | // not type-safe but we only use Arm_input_section not the base class. |
| 1063 | static Arm_input_section<big_endian>* |
| 1064 | as_arm_input_section(Output_relaxed_input_section* poris) |
| 1065 | { return static_cast<Arm_input_section<big_endian>*>(poris); } |
| 1066 | |
| 1067 | protected: |
| 1068 | // Write data to output file. |
| 1069 | void |
| 1070 | do_write(Output_file*); |
| 1071 | |
| 1072 | // Return required alignment of this. |
| 1073 | uint64_t |
| 1074 | do_addralign() const |
| 1075 | { |
| 1076 | if (this->is_stub_table_owner()) |
| 1077 | return std::max(this->stub_table_->addralign(), |
| 1078 | this->original_addralign_); |
| 1079 | else |
| 1080 | return this->original_addralign_; |
| 1081 | } |
| 1082 | |
| 1083 | // Finalize data size. |
| 1084 | void |
| 1085 | set_final_data_size(); |
| 1086 | |
| 1087 | // Reset address and file offset. |
| 1088 | void |
| 1089 | do_reset_address_and_file_offset(); |
| 1090 | |
| 1091 | // Output offset. |
| 1092 | bool |
| 1093 | do_output_offset(const Relobj* object, unsigned int shndx, |
| 1094 | section_offset_type offset, |
| 1095 | section_offset_type* poutput) const |
| 1096 | { |
| 1097 | if ((object == this->relobj()) |
| 1098 | && (shndx == this->shndx()) |
| 1099 | && (offset >= 0) |
| 1100 | && (convert_types<uint64_t, section_offset_type>(offset) |
| 1101 | <= this->original_size_)) |
| 1102 | { |
| 1103 | *poutput = offset; |
| 1104 | return true; |
| 1105 | } |
| 1106 | else |
| 1107 | return false; |
| 1108 | } |
| 1109 | |
| 1110 | private: |
| 1111 | // Copying is not allowed. |
| 1112 | Arm_input_section(const Arm_input_section&); |
| 1113 | Arm_input_section& operator=(const Arm_input_section&); |
| 1114 | |
| 1115 | // Address alignment of the original input section. |
| 1116 | uint64_t original_addralign_; |
| 1117 | // Section size of the original input section. |
| 1118 | uint64_t original_size_; |
| 1119 | // Stub table. |
| 1120 | Stub_table<big_endian>* stub_table_; |
| 1121 | }; |
| 1122 | |
| 1123 | // Arm output section class. This is defined mainly to add a number of |
| 1124 | // stub generation methods. |
| 1125 | |
| 1126 | template<bool big_endian> |
| 1127 | class Arm_output_section : public Output_section |
| 1128 | { |
| 1129 | public: |
| 1130 | Arm_output_section(const char* name, elfcpp::Elf_Word type, |
| 1131 | elfcpp::Elf_Xword flags) |
| 1132 | : Output_section(name, type, flags) |
| 1133 | { } |
| 1134 | |
| 1135 | ~Arm_output_section() |
| 1136 | { } |
| 1137 | |
| 1138 | // Group input sections for stub generation. |
| 1139 | void |
| 1140 | group_sections(section_size_type, bool, Target_arm<big_endian>*); |
| 1141 | |
| 1142 | // Downcast a base pointer to an Arm_output_section pointer. This is |
| 1143 | // not type-safe but we only use Arm_output_section not the base class. |
| 1144 | static Arm_output_section<big_endian>* |
| 1145 | as_arm_output_section(Output_section* os) |
| 1146 | { return static_cast<Arm_output_section<big_endian>*>(os); } |
| 1147 | |
| 1148 | private: |
| 1149 | // For convenience. |
| 1150 | typedef Output_section::Input_section Input_section; |
| 1151 | typedef Output_section::Input_section_list Input_section_list; |
| 1152 | |
| 1153 | // Create a stub group. |
| 1154 | void create_stub_group(Input_section_list::const_iterator, |
| 1155 | Input_section_list::const_iterator, |
| 1156 | Input_section_list::const_iterator, |
| 1157 | Target_arm<big_endian>*, |
| 1158 | std::vector<Output_relaxed_input_section*>*); |
| 1159 | }; |
| 1160 | |
| 1161 | // Arm_relobj class. |
| 1162 | |
| 1163 | template<bool big_endian> |
| 1164 | class Arm_relobj : public Sized_relobj<32, big_endian> |
| 1165 | { |
| 1166 | public: |
| 1167 | static const Arm_address invalid_address = static_cast<Arm_address>(-1); |
| 1168 | |
| 1169 | Arm_relobj(const std::string& name, Input_file* input_file, off_t offset, |
| 1170 | const typename elfcpp::Ehdr<32, big_endian>& ehdr) |
| 1171 | : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr), |
| 1172 | stub_tables_(), local_symbol_is_thumb_function_(), |
| 1173 | attributes_section_data_(NULL), mapping_symbols_info_(), |
| 1174 | section_has_cortex_a8_workaround_(NULL) |
| 1175 | { } |
| 1176 | |
| 1177 | ~Arm_relobj() |
| 1178 | { delete this->attributes_section_data_; } |
| 1179 | |
| 1180 | // Return the stub table of the SHNDX-th section if there is one. |
| 1181 | Stub_table<big_endian>* |
| 1182 | stub_table(unsigned int shndx) const |
| 1183 | { |
| 1184 | gold_assert(shndx < this->stub_tables_.size()); |
| 1185 | return this->stub_tables_[shndx]; |
| 1186 | } |
| 1187 | |
| 1188 | // Set STUB_TABLE to be the stub_table of the SHNDX-th section. |
| 1189 | void |
| 1190 | set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table) |
| 1191 | { |
| 1192 | gold_assert(shndx < this->stub_tables_.size()); |
| 1193 | this->stub_tables_[shndx] = stub_table; |
| 1194 | } |
| 1195 | |
| 1196 | // Whether a local symbol is a THUMB function. R_SYM is the symbol table |
| 1197 | // index. This is only valid after do_count_local_symbol is called. |
| 1198 | bool |
| 1199 | local_symbol_is_thumb_function(unsigned int r_sym) const |
| 1200 | { |
| 1201 | gold_assert(r_sym < this->local_symbol_is_thumb_function_.size()); |
| 1202 | return this->local_symbol_is_thumb_function_[r_sym]; |
| 1203 | } |
| 1204 | |
| 1205 | // Scan all relocation sections for stub generation. |
| 1206 | void |
| 1207 | scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*, |
| 1208 | const Layout*); |
| 1209 | |
| 1210 | // Convert regular input section with index SHNDX to a relaxed section. |
| 1211 | void |
| 1212 | convert_input_section_to_relaxed_section(unsigned shndx) |
| 1213 | { |
| 1214 | // The stubs have relocations and we need to process them after writing |
| 1215 | // out the stubs. So relocation now must follow section write. |
| 1216 | this->invalidate_section_offset(shndx); |
| 1217 | this->set_relocs_must_follow_section_writes(); |
| 1218 | } |
| 1219 | |
| 1220 | // Downcast a base pointer to an Arm_relobj pointer. This is |
| 1221 | // not type-safe but we only use Arm_relobj not the base class. |
| 1222 | static Arm_relobj<big_endian>* |
| 1223 | as_arm_relobj(Relobj* relobj) |
| 1224 | { return static_cast<Arm_relobj<big_endian>*>(relobj); } |
| 1225 | |
| 1226 | // Processor-specific flags in ELF file header. This is valid only after |
| 1227 | // reading symbols. |
| 1228 | elfcpp::Elf_Word |
| 1229 | processor_specific_flags() const |
| 1230 | { return this->processor_specific_flags_; } |
| 1231 | |
| 1232 | // Attribute section data This is the contents of the .ARM.attribute section |
| 1233 | // if there is one. |
| 1234 | const Attributes_section_data* |
| 1235 | attributes_section_data() const |
| 1236 | { return this->attributes_section_data_; } |
| 1237 | |
| 1238 | // Mapping symbol location. |
| 1239 | typedef std::pair<unsigned int, Arm_address> Mapping_symbol_position; |
| 1240 | |
| 1241 | // Functor for STL container. |
| 1242 | struct Mapping_symbol_position_less |
| 1243 | { |
| 1244 | bool |
| 1245 | operator()(const Mapping_symbol_position& p1, |
| 1246 | const Mapping_symbol_position& p2) const |
| 1247 | { |
| 1248 | return (p1.first < p2.first |
| 1249 | || (p1.first == p2.first && p1.second < p2.second)); |
| 1250 | } |
| 1251 | }; |
| 1252 | |
| 1253 | // We only care about the first character of a mapping symbol, so |
| 1254 | // we only store that instead of the whole symbol name. |
| 1255 | typedef std::map<Mapping_symbol_position, char, |
| 1256 | Mapping_symbol_position_less> Mapping_symbols_info; |
| 1257 | |
| 1258 | // Whether a section contains any Cortex-A8 workaround. |
| 1259 | bool |
| 1260 | section_has_cortex_a8_workaround(unsigned int shndx) const |
| 1261 | { |
| 1262 | return (this->section_has_cortex_a8_workaround_ != NULL |
| 1263 | && (*this->section_has_cortex_a8_workaround_)[shndx]); |
| 1264 | } |
| 1265 | |
| 1266 | // Mark a section that has Cortex-A8 workaround. |
| 1267 | void |
| 1268 | mark_section_for_cortex_a8_workaround(unsigned int shndx) |
| 1269 | { |
| 1270 | if (this->section_has_cortex_a8_workaround_ == NULL) |
| 1271 | this->section_has_cortex_a8_workaround_ = |
| 1272 | new std::vector<bool>(this->shnum(), false); |
| 1273 | (*this->section_has_cortex_a8_workaround_)[shndx] = true; |
| 1274 | } |
| 1275 | |
| 1276 | protected: |
| 1277 | // Post constructor setup. |
| 1278 | void |
| 1279 | do_setup() |
| 1280 | { |
| 1281 | // Call parent's setup method. |
| 1282 | Sized_relobj<32, big_endian>::do_setup(); |
| 1283 | |
| 1284 | // Initialize look-up tables. |
| 1285 | Stub_table_list empty_stub_table_list(this->shnum(), NULL); |
| 1286 | this->stub_tables_.swap(empty_stub_table_list); |
| 1287 | } |
| 1288 | |
| 1289 | // Count the local symbols. |
| 1290 | void |
| 1291 | do_count_local_symbols(Stringpool_template<char>*, |
| 1292 | Stringpool_template<char>*); |
| 1293 | |
| 1294 | void |
| 1295 | do_relocate_sections(const Symbol_table* symtab, const Layout* layout, |
| 1296 | const unsigned char* pshdrs, |
| 1297 | typename Sized_relobj<32, big_endian>::Views* pivews); |
| 1298 | |
| 1299 | // Read the symbol information. |
| 1300 | void |
| 1301 | do_read_symbols(Read_symbols_data* sd); |
| 1302 | |
| 1303 | // Process relocs for garbage collection. |
| 1304 | void |
| 1305 | do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*); |
| 1306 | |
| 1307 | private: |
| 1308 | |
| 1309 | // Whether a section needs to be scanned for relocation stubs. |
| 1310 | bool |
| 1311 | section_needs_reloc_stub_scanning(const elfcpp::Shdr<32, big_endian>&, |
| 1312 | const Relobj::Output_sections&, |
| 1313 | const Symbol_table *); |
| 1314 | |
| 1315 | // Whether a section needs to be scanned for the Cortex-A8 erratum. |
| 1316 | bool |
| 1317 | section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr<32, big_endian>&, |
| 1318 | unsigned int, Output_section*, |
| 1319 | const Symbol_table *); |
| 1320 | |
| 1321 | // Scan a section for the Cortex-A8 erratum. |
| 1322 | void |
| 1323 | scan_section_for_cortex_a8_erratum(const elfcpp::Shdr<32, big_endian>&, |
| 1324 | unsigned int, Output_section*, |
| 1325 | Target_arm<big_endian>*); |
| 1326 | |
| 1327 | // List of stub tables. |
| 1328 | typedef std::vector<Stub_table<big_endian>*> Stub_table_list; |
| 1329 | Stub_table_list stub_tables_; |
| 1330 | // Bit vector to tell if a local symbol is a thumb function or not. |
| 1331 | // This is only valid after do_count_local_symbol is called. |
| 1332 | std::vector<bool> local_symbol_is_thumb_function_; |
| 1333 | // processor-specific flags in ELF file header. |
| 1334 | elfcpp::Elf_Word processor_specific_flags_; |
| 1335 | // Object attributes if there is an .ARM.attributes section or NULL. |
| 1336 | Attributes_section_data* attributes_section_data_; |
| 1337 | // Mapping symbols information. |
| 1338 | Mapping_symbols_info mapping_symbols_info_; |
| 1339 | // Bitmap to indicate sections with Cortex-A8 workaround or NULL. |
| 1340 | std::vector<bool>* section_has_cortex_a8_workaround_; |
| 1341 | }; |
| 1342 | |
| 1343 | // Arm_dynobj class. |
| 1344 | |
| 1345 | template<bool big_endian> |
| 1346 | class Arm_dynobj : public Sized_dynobj<32, big_endian> |
| 1347 | { |
| 1348 | public: |
| 1349 | Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset, |
| 1350 | const elfcpp::Ehdr<32, big_endian>& ehdr) |
| 1351 | : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr), |
| 1352 | processor_specific_flags_(0), attributes_section_data_(NULL) |
| 1353 | { } |
| 1354 | |
| 1355 | ~Arm_dynobj() |
| 1356 | { delete this->attributes_section_data_; } |
| 1357 | |
| 1358 | // Downcast a base pointer to an Arm_relobj pointer. This is |
| 1359 | // not type-safe but we only use Arm_relobj not the base class. |
| 1360 | static Arm_dynobj<big_endian>* |
| 1361 | as_arm_dynobj(Dynobj* dynobj) |
| 1362 | { return static_cast<Arm_dynobj<big_endian>*>(dynobj); } |
| 1363 | |
| 1364 | // Processor-specific flags in ELF file header. This is valid only after |
| 1365 | // reading symbols. |
| 1366 | elfcpp::Elf_Word |
| 1367 | processor_specific_flags() const |
| 1368 | { return this->processor_specific_flags_; } |
| 1369 | |
| 1370 | // Attributes section data. |
| 1371 | const Attributes_section_data* |
| 1372 | attributes_section_data() const |
| 1373 | { return this->attributes_section_data_; } |
| 1374 | |
| 1375 | protected: |
| 1376 | // Read the symbol information. |
| 1377 | void |
| 1378 | do_read_symbols(Read_symbols_data* sd); |
| 1379 | |
| 1380 | private: |
| 1381 | // processor-specific flags in ELF file header. |
| 1382 | elfcpp::Elf_Word processor_specific_flags_; |
| 1383 | // Object attributes if there is an .ARM.attributes section or NULL. |
| 1384 | Attributes_section_data* attributes_section_data_; |
| 1385 | }; |
| 1386 | |
| 1387 | // Functor to read reloc addends during stub generation. |
| 1388 | |
| 1389 | template<int sh_type, bool big_endian> |
| 1390 | struct Stub_addend_reader |
| 1391 | { |
| 1392 | // Return the addend for a relocation of a particular type. Depending |
| 1393 | // on whether this is a REL or RELA relocation, read the addend from a |
| 1394 | // view or from a Reloc object. |
| 1395 | elfcpp::Elf_types<32>::Elf_Swxword |
| 1396 | operator()( |
| 1397 | unsigned int /* r_type */, |
| 1398 | const unsigned char* /* view */, |
| 1399 | const typename Reloc_types<sh_type, |
| 1400 | 32, big_endian>::Reloc& /* reloc */) const; |
| 1401 | }; |
| 1402 | |
| 1403 | // Specialized Stub_addend_reader for SHT_REL type relocation sections. |
| 1404 | |
| 1405 | template<bool big_endian> |
| 1406 | struct Stub_addend_reader<elfcpp::SHT_REL, big_endian> |
| 1407 | { |
| 1408 | elfcpp::Elf_types<32>::Elf_Swxword |
| 1409 | operator()( |
| 1410 | unsigned int, |
| 1411 | const unsigned char*, |
| 1412 | const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const; |
| 1413 | }; |
| 1414 | |
| 1415 | // Specialized Stub_addend_reader for RELA type relocation sections. |
| 1416 | // We currently do not handle RELA type relocation sections but it is trivial |
| 1417 | // to implement the addend reader. This is provided for completeness and to |
| 1418 | // make it easier to add support for RELA relocation sections in the future. |
| 1419 | |
| 1420 | template<bool big_endian> |
| 1421 | struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian> |
| 1422 | { |
| 1423 | elfcpp::Elf_types<32>::Elf_Swxword |
| 1424 | operator()( |
| 1425 | unsigned int, |
| 1426 | const unsigned char*, |
| 1427 | const typename Reloc_types<elfcpp::SHT_RELA, 32, |
| 1428 | big_endian>::Reloc& reloc) const |
| 1429 | { return reloc.get_r_addend(); } |
| 1430 | }; |
| 1431 | |
| 1432 | // Cortex_a8_reloc class. We keep record of relocation that may need |
| 1433 | // the Cortex-A8 erratum workaround. |
| 1434 | |
| 1435 | class Cortex_a8_reloc |
| 1436 | { |
| 1437 | public: |
| 1438 | Cortex_a8_reloc(Reloc_stub* reloc_stub, unsigned r_type, |
| 1439 | Arm_address destination) |
| 1440 | : reloc_stub_(reloc_stub), r_type_(r_type), destination_(destination) |
| 1441 | { } |
| 1442 | |
| 1443 | ~Cortex_a8_reloc() |
| 1444 | { } |
| 1445 | |
| 1446 | // Accessors: This is a read-only class. |
| 1447 | |
| 1448 | // Return the relocation stub associated with this relocation if there is |
| 1449 | // one. |
| 1450 | const Reloc_stub* |
| 1451 | reloc_stub() const |
| 1452 | { return this->reloc_stub_; } |
| 1453 | |
| 1454 | // Return the relocation type. |
| 1455 | unsigned int |
| 1456 | r_type() const |
| 1457 | { return this->r_type_; } |
| 1458 | |
| 1459 | // Return the destination address of the relocation. LSB stores the THUMB |
| 1460 | // bit. |
| 1461 | Arm_address |
| 1462 | destination() const |
| 1463 | { return this->destination_; } |
| 1464 | |
| 1465 | private: |
| 1466 | // Associated relocation stub if there is one, or NULL. |
| 1467 | const Reloc_stub* reloc_stub_; |
| 1468 | // Relocation type. |
| 1469 | unsigned int r_type_; |
| 1470 | // Destination address of this relocation. LSB is used to distinguish |
| 1471 | // ARM/THUMB mode. |
| 1472 | Arm_address destination_; |
| 1473 | }; |
| 1474 | |
| 1475 | // Utilities for manipulating integers of up to 32-bits |
| 1476 | |
| 1477 | namespace utils |
| 1478 | { |
| 1479 | // Sign extend an n-bit unsigned integer stored in an uint32_t into |
| 1480 | // an int32_t. NO_BITS must be between 1 to 32. |
| 1481 | template<int no_bits> |
| 1482 | static inline int32_t |
| 1483 | sign_extend(uint32_t bits) |
| 1484 | { |
| 1485 | gold_assert(no_bits >= 0 && no_bits <= 32); |
| 1486 | if (no_bits == 32) |
| 1487 | return static_cast<int32_t>(bits); |
| 1488 | uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits); |
| 1489 | bits &= mask; |
| 1490 | uint32_t top_bit = 1U << (no_bits - 1); |
| 1491 | int32_t as_signed = static_cast<int32_t>(bits); |
| 1492 | return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed; |
| 1493 | } |
| 1494 | |
| 1495 | // Detects overflow of an NO_BITS integer stored in a uint32_t. |
| 1496 | template<int no_bits> |
| 1497 | static inline bool |
| 1498 | has_overflow(uint32_t bits) |
| 1499 | { |
| 1500 | gold_assert(no_bits >= 0 && no_bits <= 32); |
| 1501 | if (no_bits == 32) |
| 1502 | return false; |
| 1503 | int32_t max = (1 << (no_bits - 1)) - 1; |
| 1504 | int32_t min = -(1 << (no_bits - 1)); |
| 1505 | int32_t as_signed = static_cast<int32_t>(bits); |
| 1506 | return as_signed > max || as_signed < min; |
| 1507 | } |
| 1508 | |
| 1509 | // Detects overflow of an NO_BITS integer stored in a uint32_t when it |
| 1510 | // fits in the given number of bits as either a signed or unsigned value. |
| 1511 | // For example, has_signed_unsigned_overflow<8> would check |
| 1512 | // -128 <= bits <= 255 |
| 1513 | template<int no_bits> |
| 1514 | static inline bool |
| 1515 | has_signed_unsigned_overflow(uint32_t bits) |
| 1516 | { |
| 1517 | gold_assert(no_bits >= 2 && no_bits <= 32); |
| 1518 | if (no_bits == 32) |
| 1519 | return false; |
| 1520 | int32_t max = static_cast<int32_t>((1U << no_bits) - 1); |
| 1521 | int32_t min = -(1 << (no_bits - 1)); |
| 1522 | int32_t as_signed = static_cast<int32_t>(bits); |
| 1523 | return as_signed > max || as_signed < min; |
| 1524 | } |
| 1525 | |
| 1526 | // Select bits from A and B using bits in MASK. For each n in [0..31], |
| 1527 | // the n-th bit in the result is chosen from the n-th bits of A and B. |
| 1528 | // A zero selects A and a one selects B. |
| 1529 | static inline uint32_t |
| 1530 | bit_select(uint32_t a, uint32_t b, uint32_t mask) |
| 1531 | { return (a & ~mask) | (b & mask); } |
| 1532 | }; |
| 1533 | |
| 1534 | template<bool big_endian> |
| 1535 | class Target_arm : public Sized_target<32, big_endian> |
| 1536 | { |
| 1537 | public: |
| 1538 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian> |
| 1539 | Reloc_section; |
| 1540 | |
| 1541 | // When were are relocating a stub, we pass this as the relocation number. |
| 1542 | static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1); |
| 1543 | |
| 1544 | Target_arm() |
| 1545 | : Sized_target<32, big_endian>(&arm_info), |
| 1546 | got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), |
| 1547 | copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL), stub_tables_(), |
| 1548 | stub_factory_(Stub_factory::get_instance()), may_use_blx_(false), |
| 1549 | should_force_pic_veneer_(false), arm_input_section_map_(), |
| 1550 | attributes_section_data_(NULL), fix_cortex_a8_(false), |
| 1551 | cortex_a8_relocs_info_(), fix_v4bx_(0) |
| 1552 | { } |
| 1553 | |
| 1554 | // Whether we can use BLX. |
| 1555 | bool |
| 1556 | may_use_blx() const |
| 1557 | { return this->may_use_blx_; } |
| 1558 | |
| 1559 | // Set use-BLX flag. |
| 1560 | void |
| 1561 | set_may_use_blx(bool value) |
| 1562 | { this->may_use_blx_ = value; } |
| 1563 | |
| 1564 | // Whether we force PCI branch veneers. |
| 1565 | bool |
| 1566 | should_force_pic_veneer() const |
| 1567 | { return this->should_force_pic_veneer_; } |
| 1568 | |
| 1569 | // Set PIC veneer flag. |
| 1570 | void |
| 1571 | set_should_force_pic_veneer(bool value) |
| 1572 | { this->should_force_pic_veneer_ = value; } |
| 1573 | |
| 1574 | // Whether we use THUMB-2 instructions. |
| 1575 | bool |
| 1576 | using_thumb2() const |
| 1577 | { |
| 1578 | Object_attribute* attr = |
| 1579 | this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch); |
| 1580 | int arch = attr->int_value(); |
| 1581 | return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7; |
| 1582 | } |
| 1583 | |
| 1584 | // Whether we use THUMB/THUMB-2 instructions only. |
| 1585 | bool |
| 1586 | using_thumb_only() const |
| 1587 | { |
| 1588 | Object_attribute* attr = |
| 1589 | this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch); |
| 1590 | if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7 |
| 1591 | && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M) |
| 1592 | return false; |
| 1593 | attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile); |
| 1594 | return attr->int_value() == 'M'; |
| 1595 | } |
| 1596 | |
| 1597 | // Whether we have an NOP instruction. If not, use mov r0, r0 instead. |
| 1598 | bool |
| 1599 | may_use_arm_nop() const |
| 1600 | { |
| 1601 | Object_attribute* attr = |
| 1602 | this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch); |
| 1603 | int arch = attr->int_value(); |
| 1604 | return (arch == elfcpp::TAG_CPU_ARCH_V6T2 |
| 1605 | || arch == elfcpp::TAG_CPU_ARCH_V6K |
| 1606 | || arch == elfcpp::TAG_CPU_ARCH_V7 |
| 1607 | || arch == elfcpp::TAG_CPU_ARCH_V7E_M); |
| 1608 | } |
| 1609 | |
| 1610 | // Whether we have THUMB-2 NOP.W instruction. |
| 1611 | bool |
| 1612 | may_use_thumb2_nop() const |
| 1613 | { |
| 1614 | Object_attribute* attr = |
| 1615 | this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch); |
| 1616 | int arch = attr->int_value(); |
| 1617 | return (arch == elfcpp::TAG_CPU_ARCH_V6T2 |
| 1618 | || arch == elfcpp::TAG_CPU_ARCH_V7 |
| 1619 | || arch == elfcpp::TAG_CPU_ARCH_V7E_M); |
| 1620 | } |
| 1621 | |
| 1622 | // Process the relocations to determine unreferenced sections for |
| 1623 | // garbage collection. |
| 1624 | void |
| 1625 | gc_process_relocs(Symbol_table* symtab, |
| 1626 | Layout* layout, |
| 1627 | Sized_relobj<32, big_endian>* object, |
| 1628 | unsigned int data_shndx, |
| 1629 | unsigned int sh_type, |
| 1630 | const unsigned char* prelocs, |
| 1631 | size_t reloc_count, |
| 1632 | Output_section* output_section, |
| 1633 | bool needs_special_offset_handling, |
| 1634 | size_t local_symbol_count, |
| 1635 | const unsigned char* plocal_symbols); |
| 1636 | |
| 1637 | // Scan the relocations to look for symbol adjustments. |
| 1638 | void |
| 1639 | scan_relocs(Symbol_table* symtab, |
| 1640 | Layout* layout, |
| 1641 | Sized_relobj<32, big_endian>* object, |
| 1642 | unsigned int data_shndx, |
| 1643 | unsigned int sh_type, |
| 1644 | const unsigned char* prelocs, |
| 1645 | size_t reloc_count, |
| 1646 | Output_section* output_section, |
| 1647 | bool needs_special_offset_handling, |
| 1648 | size_t local_symbol_count, |
| 1649 | const unsigned char* plocal_symbols); |
| 1650 | |
| 1651 | // Finalize the sections. |
| 1652 | void |
| 1653 | do_finalize_sections(Layout*, const Input_objects*, Symbol_table*); |
| 1654 | |
| 1655 | // Return the value to use for a dynamic symbol which requires special |
| 1656 | // treatment. |
| 1657 | uint64_t |
| 1658 | do_dynsym_value(const Symbol*) const; |
| 1659 | |
| 1660 | // Relocate a section. |
| 1661 | void |
| 1662 | relocate_section(const Relocate_info<32, big_endian>*, |
| 1663 | unsigned int sh_type, |
| 1664 | const unsigned char* prelocs, |
| 1665 | size_t reloc_count, |
| 1666 | Output_section* output_section, |
| 1667 | bool needs_special_offset_handling, |
| 1668 | unsigned char* view, |
| 1669 | Arm_address view_address, |
| 1670 | section_size_type view_size, |
| 1671 | const Reloc_symbol_changes*); |
| 1672 | |
| 1673 | // Scan the relocs during a relocatable link. |
| 1674 | void |
| 1675 | scan_relocatable_relocs(Symbol_table* symtab, |
| 1676 | Layout* layout, |
| 1677 | Sized_relobj<32, big_endian>* object, |
| 1678 | unsigned int data_shndx, |
| 1679 | unsigned int sh_type, |
| 1680 | const unsigned char* prelocs, |
| 1681 | size_t reloc_count, |
| 1682 | Output_section* output_section, |
| 1683 | bool needs_special_offset_handling, |
| 1684 | size_t local_symbol_count, |
| 1685 | const unsigned char* plocal_symbols, |
| 1686 | Relocatable_relocs*); |
| 1687 | |
| 1688 | // Relocate a section during a relocatable link. |
| 1689 | void |
| 1690 | relocate_for_relocatable(const Relocate_info<32, big_endian>*, |
| 1691 | unsigned int sh_type, |
| 1692 | const unsigned char* prelocs, |
| 1693 | size_t reloc_count, |
| 1694 | Output_section* output_section, |
| 1695 | off_t offset_in_output_section, |
| 1696 | const Relocatable_relocs*, |
| 1697 | unsigned char* view, |
| 1698 | Arm_address view_address, |
| 1699 | section_size_type view_size, |
| 1700 | unsigned char* reloc_view, |
| 1701 | section_size_type reloc_view_size); |
| 1702 | |
| 1703 | // Return whether SYM is defined by the ABI. |
| 1704 | bool |
| 1705 | do_is_defined_by_abi(Symbol* sym) const |
| 1706 | { return strcmp(sym->name(), "__tls_get_addr") == 0; } |
| 1707 | |
| 1708 | // Return the size of the GOT section. |
| 1709 | section_size_type |
| 1710 | got_size() |
| 1711 | { |
| 1712 | gold_assert(this->got_ != NULL); |
| 1713 | return this->got_->data_size(); |
| 1714 | } |
| 1715 | |
| 1716 | // Map platform-specific reloc types |
| 1717 | static unsigned int |
| 1718 | get_real_reloc_type (unsigned int r_type); |
| 1719 | |
| 1720 | // |
| 1721 | // Methods to support stub-generations. |
| 1722 | // |
| 1723 | |
| 1724 | // Return the stub factory |
| 1725 | const Stub_factory& |
| 1726 | stub_factory() const |
| 1727 | { return this->stub_factory_; } |
| 1728 | |
| 1729 | // Make a new Arm_input_section object. |
| 1730 | Arm_input_section<big_endian>* |
| 1731 | new_arm_input_section(Relobj*, unsigned int); |
| 1732 | |
| 1733 | // Find the Arm_input_section object corresponding to the SHNDX-th input |
| 1734 | // section of RELOBJ. |
| 1735 | Arm_input_section<big_endian>* |
| 1736 | find_arm_input_section(Relobj* relobj, unsigned int shndx) const; |
| 1737 | |
| 1738 | // Make a new Stub_table |
| 1739 | Stub_table<big_endian>* |
| 1740 | new_stub_table(Arm_input_section<big_endian>*); |
| 1741 | |
| 1742 | // Scan a section for stub generation. |
| 1743 | void |
| 1744 | scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int, |
| 1745 | const unsigned char*, size_t, Output_section*, |
| 1746 | bool, const unsigned char*, Arm_address, |
| 1747 | section_size_type); |
| 1748 | |
| 1749 | // Relocate a stub. |
| 1750 | void |
| 1751 | relocate_stub(Stub*, const Relocate_info<32, big_endian>*, |
| 1752 | Output_section*, unsigned char*, Arm_address, |
| 1753 | section_size_type); |
| 1754 | |
| 1755 | // Get the default ARM target. |
| 1756 | static Target_arm<big_endian>* |
| 1757 | default_target() |
| 1758 | { |
| 1759 | gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM |
| 1760 | && parameters->target().is_big_endian() == big_endian); |
| 1761 | return static_cast<Target_arm<big_endian>*>( |
| 1762 | parameters->sized_target<32, big_endian>()); |
| 1763 | } |
| 1764 | |
| 1765 | // Whether relocation type uses LSB to distinguish THUMB addresses. |
| 1766 | static bool |
| 1767 | reloc_uses_thumb_bit(unsigned int r_type); |
| 1768 | |
| 1769 | // Whether NAME belongs to a mapping symbol. |
| 1770 | static bool |
| 1771 | is_mapping_symbol_name(const char* name) |
| 1772 | { |
| 1773 | return (name |
| 1774 | && name[0] == '$' |
| 1775 | && (name[1] == 'a' || name[1] == 't' || name[1] == 'd') |
| 1776 | && (name[2] == '\0' || name[2] == '.')); |
| 1777 | } |
| 1778 | |
| 1779 | // Whether we work around the Cortex-A8 erratum. |
| 1780 | bool |
| 1781 | fix_cortex_a8() const |
| 1782 | { return this->fix_cortex_a8_; } |
| 1783 | |
| 1784 | // Whether we fix R_ARM_V4BX relocation. |
| 1785 | // 0 - do not fix |
| 1786 | // 1 - replace with MOV instruction (armv4 target) |
| 1787 | // 2 - make interworking veneer (>= armv4t targets only) |
| 1788 | int |
| 1789 | fix_v4bx() const |
| 1790 | { return this->fix_v4bx_; } |
| 1791 | |
| 1792 | // Scan a span of THUMB code section for Cortex-A8 erratum. |
| 1793 | void |
| 1794 | scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int, |
| 1795 | section_size_type, section_size_type, |
| 1796 | const unsigned char*, Arm_address); |
| 1797 | |
| 1798 | // Apply Cortex-A8 workaround to a branch. |
| 1799 | void |
| 1800 | apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address, |
| 1801 | unsigned char*, Arm_address); |
| 1802 | |
| 1803 | protected: |
| 1804 | // Make an ELF object. |
| 1805 | Object* |
| 1806 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1807 | const elfcpp::Ehdr<32, big_endian>& ehdr); |
| 1808 | |
| 1809 | Object* |
| 1810 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1811 | const elfcpp::Ehdr<32, !big_endian>&) |
| 1812 | { gold_unreachable(); } |
| 1813 | |
| 1814 | Object* |
| 1815 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1816 | const elfcpp::Ehdr<64, false>&) |
| 1817 | { gold_unreachable(); } |
| 1818 | |
| 1819 | Object* |
| 1820 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1821 | const elfcpp::Ehdr<64, true>&) |
| 1822 | { gold_unreachable(); } |
| 1823 | |
| 1824 | // Make an output section. |
| 1825 | Output_section* |
| 1826 | do_make_output_section(const char* name, elfcpp::Elf_Word type, |
| 1827 | elfcpp::Elf_Xword flags) |
| 1828 | { return new Arm_output_section<big_endian>(name, type, flags); } |
| 1829 | |
| 1830 | void |
| 1831 | do_adjust_elf_header(unsigned char* view, int len) const; |
| 1832 | |
| 1833 | // We only need to generate stubs, and hence perform relaxation if we are |
| 1834 | // not doing relocatable linking. |
| 1835 | bool |
| 1836 | do_may_relax() const |
| 1837 | { return !parameters->options().relocatable(); } |
| 1838 | |
| 1839 | bool |
| 1840 | do_relax(int, const Input_objects*, Symbol_table*, Layout*); |
| 1841 | |
| 1842 | // Determine whether an object attribute tag takes an integer, a |
| 1843 | // string or both. |
| 1844 | int |
| 1845 | do_attribute_arg_type(int tag) const; |
| 1846 | |
| 1847 | // Reorder tags during output. |
| 1848 | int |
| 1849 | do_attributes_order(int num) const; |
| 1850 | |
| 1851 | private: |
| 1852 | // The class which scans relocations. |
| 1853 | class Scan |
| 1854 | { |
| 1855 | public: |
| 1856 | Scan() |
| 1857 | : issued_non_pic_error_(false) |
| 1858 | { } |
| 1859 | |
| 1860 | inline void |
| 1861 | local(Symbol_table* symtab, Layout* layout, Target_arm* target, |
| 1862 | Sized_relobj<32, big_endian>* object, |
| 1863 | unsigned int data_shndx, |
| 1864 | Output_section* output_section, |
| 1865 | const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type, |
| 1866 | const elfcpp::Sym<32, big_endian>& lsym); |
| 1867 | |
| 1868 | inline void |
| 1869 | global(Symbol_table* symtab, Layout* layout, Target_arm* target, |
| 1870 | Sized_relobj<32, big_endian>* object, |
| 1871 | unsigned int data_shndx, |
| 1872 | Output_section* output_section, |
| 1873 | const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type, |
| 1874 | Symbol* gsym); |
| 1875 | |
| 1876 | private: |
| 1877 | static void |
| 1878 | unsupported_reloc_local(Sized_relobj<32, big_endian>*, |
| 1879 | unsigned int r_type); |
| 1880 | |
| 1881 | static void |
| 1882 | unsupported_reloc_global(Sized_relobj<32, big_endian>*, |
| 1883 | unsigned int r_type, Symbol*); |
| 1884 | |
| 1885 | void |
| 1886 | check_non_pic(Relobj*, unsigned int r_type); |
| 1887 | |
| 1888 | // Almost identical to Symbol::needs_plt_entry except that it also |
| 1889 | // handles STT_ARM_TFUNC. |
| 1890 | static bool |
| 1891 | symbol_needs_plt_entry(const Symbol* sym) |
| 1892 | { |
| 1893 | // An undefined symbol from an executable does not need a PLT entry. |
| 1894 | if (sym->is_undefined() && !parameters->options().shared()) |
| 1895 | return false; |
| 1896 | |
| 1897 | return (!parameters->doing_static_link() |
| 1898 | && (sym->type() == elfcpp::STT_FUNC |
| 1899 | || sym->type() == elfcpp::STT_ARM_TFUNC) |
| 1900 | && (sym->is_from_dynobj() |
| 1901 | || sym->is_undefined() |
| 1902 | || sym->is_preemptible())); |
| 1903 | } |
| 1904 | |
| 1905 | // Whether we have issued an error about a non-PIC compilation. |
| 1906 | bool issued_non_pic_error_; |
| 1907 | }; |
| 1908 | |
| 1909 | // The class which implements relocation. |
| 1910 | class Relocate |
| 1911 | { |
| 1912 | public: |
| 1913 | Relocate() |
| 1914 | { } |
| 1915 | |
| 1916 | ~Relocate() |
| 1917 | { } |
| 1918 | |
| 1919 | // Return whether the static relocation needs to be applied. |
| 1920 | inline bool |
| 1921 | should_apply_static_reloc(const Sized_symbol<32>* gsym, |
| 1922 | int ref_flags, |
| 1923 | bool is_32bit, |
| 1924 | Output_section* output_section); |
| 1925 | |
| 1926 | // Do a relocation. Return false if the caller should not issue |
| 1927 | // any warnings about this relocation. |
| 1928 | inline bool |
| 1929 | relocate(const Relocate_info<32, big_endian>*, Target_arm*, |
| 1930 | Output_section*, size_t relnum, |
| 1931 | const elfcpp::Rel<32, big_endian>&, |
| 1932 | unsigned int r_type, const Sized_symbol<32>*, |
| 1933 | const Symbol_value<32>*, |
| 1934 | unsigned char*, Arm_address, |
| 1935 | section_size_type); |
| 1936 | |
| 1937 | // Return whether we want to pass flag NON_PIC_REF for this |
| 1938 | // reloc. This means the relocation type accesses a symbol not via |
| 1939 | // GOT or PLT. |
| 1940 | static inline bool |
| 1941 | reloc_is_non_pic (unsigned int r_type) |
| 1942 | { |
| 1943 | switch (r_type) |
| 1944 | { |
| 1945 | // These relocation types reference GOT or PLT entries explicitly. |
| 1946 | case elfcpp::R_ARM_GOT_BREL: |
| 1947 | case elfcpp::R_ARM_GOT_ABS: |
| 1948 | case elfcpp::R_ARM_GOT_PREL: |
| 1949 | case elfcpp::R_ARM_GOT_BREL12: |
| 1950 | case elfcpp::R_ARM_PLT32_ABS: |
| 1951 | case elfcpp::R_ARM_TLS_GD32: |
| 1952 | case elfcpp::R_ARM_TLS_LDM32: |
| 1953 | case elfcpp::R_ARM_TLS_IE32: |
| 1954 | case elfcpp::R_ARM_TLS_IE12GP: |
| 1955 | |
| 1956 | // These relocate types may use PLT entries. |
| 1957 | case elfcpp::R_ARM_CALL: |
| 1958 | case elfcpp::R_ARM_THM_CALL: |
| 1959 | case elfcpp::R_ARM_JUMP24: |
| 1960 | case elfcpp::R_ARM_THM_JUMP24: |
| 1961 | case elfcpp::R_ARM_THM_JUMP19: |
| 1962 | case elfcpp::R_ARM_PLT32: |
| 1963 | case elfcpp::R_ARM_THM_XPC22: |
| 1964 | return false; |
| 1965 | |
| 1966 | default: |
| 1967 | return true; |
| 1968 | } |
| 1969 | } |
| 1970 | }; |
| 1971 | |
| 1972 | // A class which returns the size required for a relocation type, |
| 1973 | // used while scanning relocs during a relocatable link. |
| 1974 | class Relocatable_size_for_reloc |
| 1975 | { |
| 1976 | public: |
| 1977 | unsigned int |
| 1978 | get_size_for_reloc(unsigned int, Relobj*); |
| 1979 | }; |
| 1980 | |
| 1981 | // Get the GOT section, creating it if necessary. |
| 1982 | Output_data_got<32, big_endian>* |
| 1983 | got_section(Symbol_table*, Layout*); |
| 1984 | |
| 1985 | // Get the GOT PLT section. |
| 1986 | Output_data_space* |
| 1987 | got_plt_section() const |
| 1988 | { |
| 1989 | gold_assert(this->got_plt_ != NULL); |
| 1990 | return this->got_plt_; |
| 1991 | } |
| 1992 | |
| 1993 | // Create a PLT entry for a global symbol. |
| 1994 | void |
| 1995 | make_plt_entry(Symbol_table*, Layout*, Symbol*); |
| 1996 | |
| 1997 | // Get the PLT section. |
| 1998 | const Output_data_plt_arm<big_endian>* |
| 1999 | plt_section() const |
| 2000 | { |
| 2001 | gold_assert(this->plt_ != NULL); |
| 2002 | return this->plt_; |
| 2003 | } |
| 2004 | |
| 2005 | // Get the dynamic reloc section, creating it if necessary. |
| 2006 | Reloc_section* |
| 2007 | rel_dyn_section(Layout*); |
| 2008 | |
| 2009 | // Return true if the symbol may need a COPY relocation. |
| 2010 | // References from an executable object to non-function symbols |
| 2011 | // defined in a dynamic object may need a COPY relocation. |
| 2012 | bool |
| 2013 | may_need_copy_reloc(Symbol* gsym) |
| 2014 | { |
| 2015 | return (gsym->type() != elfcpp::STT_ARM_TFUNC |
| 2016 | && gsym->may_need_copy_reloc()); |
| 2017 | } |
| 2018 | |
| 2019 | // Add a potential copy relocation. |
| 2020 | void |
| 2021 | copy_reloc(Symbol_table* symtab, Layout* layout, |
| 2022 | Sized_relobj<32, big_endian>* object, |
| 2023 | unsigned int shndx, Output_section* output_section, |
| 2024 | Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc) |
| 2025 | { |
| 2026 | this->copy_relocs_.copy_reloc(symtab, layout, |
| 2027 | symtab->get_sized_symbol<32>(sym), |
| 2028 | object, shndx, output_section, reloc, |
| 2029 | this->rel_dyn_section(layout)); |
| 2030 | } |
| 2031 | |
| 2032 | // Whether two EABI versions are compatible. |
| 2033 | static bool |
| 2034 | are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2); |
| 2035 | |
| 2036 | // Merge processor-specific flags from input object and those in the ELF |
| 2037 | // header of the output. |
| 2038 | void |
| 2039 | merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word); |
| 2040 | |
| 2041 | // Get the secondary compatible architecture. |
| 2042 | static int |
| 2043 | get_secondary_compatible_arch(const Attributes_section_data*); |
| 2044 | |
| 2045 | // Set the secondary compatible architecture. |
| 2046 | static void |
| 2047 | set_secondary_compatible_arch(Attributes_section_data*, int); |
| 2048 | |
| 2049 | static int |
| 2050 | tag_cpu_arch_combine(const char*, int, int*, int, int); |
| 2051 | |
| 2052 | // Helper to print AEABI enum tag value. |
| 2053 | static std::string |
| 2054 | aeabi_enum_name(unsigned int); |
| 2055 | |
| 2056 | // Return string value for TAG_CPU_name. |
| 2057 | static std::string |
| 2058 | tag_cpu_name_value(unsigned int); |
| 2059 | |
| 2060 | // Merge object attributes from input object and those in the output. |
| 2061 | void |
| 2062 | merge_object_attributes(const char*, const Attributes_section_data*); |
| 2063 | |
| 2064 | // Helper to get an AEABI object attribute |
| 2065 | Object_attribute* |
| 2066 | get_aeabi_object_attribute(int tag) const |
| 2067 | { |
| 2068 | Attributes_section_data* pasd = this->attributes_section_data_; |
| 2069 | gold_assert(pasd != NULL); |
| 2070 | Object_attribute* attr = |
| 2071 | pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag); |
| 2072 | gold_assert(attr != NULL); |
| 2073 | return attr; |
| 2074 | } |
| 2075 | |
| 2076 | // |
| 2077 | // Methods to support stub-generations. |
| 2078 | // |
| 2079 | |
| 2080 | // Group input sections for stub generation. |
| 2081 | void |
| 2082 | group_sections(Layout*, section_size_type, bool); |
| 2083 | |
| 2084 | // Scan a relocation for stub generation. |
| 2085 | void |
| 2086 | scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int, |
| 2087 | const Sized_symbol<32>*, unsigned int, |
| 2088 | const Symbol_value<32>*, |
| 2089 | elfcpp::Elf_types<32>::Elf_Swxword, Arm_address); |
| 2090 | |
| 2091 | // Scan a relocation section for stub. |
| 2092 | template<int sh_type> |
| 2093 | void |
| 2094 | scan_reloc_section_for_stubs( |
| 2095 | const Relocate_info<32, big_endian>* relinfo, |
| 2096 | const unsigned char* prelocs, |
| 2097 | size_t reloc_count, |
| 2098 | Output_section* output_section, |
| 2099 | bool needs_special_offset_handling, |
| 2100 | const unsigned char* view, |
| 2101 | elfcpp::Elf_types<32>::Elf_Addr view_address, |
| 2102 | section_size_type); |
| 2103 | |
| 2104 | // Information about this specific target which we pass to the |
| 2105 | // general Target structure. |
| 2106 | static const Target::Target_info arm_info; |
| 2107 | |
| 2108 | // The types of GOT entries needed for this platform. |
| 2109 | enum Got_type |
| 2110 | { |
| 2111 | GOT_TYPE_STANDARD = 0 // GOT entry for a regular symbol |
| 2112 | }; |
| 2113 | |
| 2114 | typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list; |
| 2115 | |
| 2116 | // Map input section to Arm_input_section. |
| 2117 | typedef Unordered_map<Input_section_specifier, |
| 2118 | Arm_input_section<big_endian>*, |
| 2119 | Input_section_specifier::hash, |
| 2120 | Input_section_specifier::equal_to> |
| 2121 | Arm_input_section_map; |
| 2122 | |
| 2123 | // Map output addresses to relocs for Cortex-A8 erratum. |
| 2124 | typedef Unordered_map<Arm_address, const Cortex_a8_reloc*> |
| 2125 | Cortex_a8_relocs_info; |
| 2126 | |
| 2127 | // The GOT section. |
| 2128 | Output_data_got<32, big_endian>* got_; |
| 2129 | // The PLT section. |
| 2130 | Output_data_plt_arm<big_endian>* plt_; |
| 2131 | // The GOT PLT section. |
| 2132 | Output_data_space* got_plt_; |
| 2133 | // The dynamic reloc section. |
| 2134 | Reloc_section* rel_dyn_; |
| 2135 | // Relocs saved to avoid a COPY reloc. |
| 2136 | Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_; |
| 2137 | // Space for variables copied with a COPY reloc. |
| 2138 | Output_data_space* dynbss_; |
| 2139 | // Vector of Stub_tables created. |
| 2140 | Stub_table_list stub_tables_; |
| 2141 | // Stub factory. |
| 2142 | const Stub_factory &stub_factory_; |
| 2143 | // Whether we can use BLX. |
| 2144 | bool may_use_blx_; |
| 2145 | // Whether we force PIC branch veneers. |
| 2146 | bool should_force_pic_veneer_; |
| 2147 | // Map for locating Arm_input_sections. |
| 2148 | Arm_input_section_map arm_input_section_map_; |
| 2149 | // Attributes section data in output. |
| 2150 | Attributes_section_data* attributes_section_data_; |
| 2151 | // Whether we want to fix code for Cortex-A8 erratum. |
| 2152 | bool fix_cortex_a8_; |
| 2153 | // Map addresses to relocs for Cortex-A8 erratum. |
| 2154 | Cortex_a8_relocs_info cortex_a8_relocs_info_; |
| 2155 | // Whether we need to fix code for V4BX relocations. |
| 2156 | int fix_v4bx_; |
| 2157 | }; |
| 2158 | |
| 2159 | template<bool big_endian> |
| 2160 | const Target::Target_info Target_arm<big_endian>::arm_info = |
| 2161 | { |
| 2162 | 32, // size |
| 2163 | big_endian, // is_big_endian |
| 2164 | elfcpp::EM_ARM, // machine_code |
| 2165 | false, // has_make_symbol |
| 2166 | false, // has_resolve |
| 2167 | false, // has_code_fill |
| 2168 | true, // is_default_stack_executable |
| 2169 | '\0', // wrap_char |
| 2170 | "/usr/lib/libc.so.1", // dynamic_linker |
| 2171 | 0x8000, // default_text_segment_address |
| 2172 | 0x1000, // abi_pagesize (overridable by -z max-page-size) |
| 2173 | 0x1000, // common_pagesize (overridable by -z common-page-size) |
| 2174 | elfcpp::SHN_UNDEF, // small_common_shndx |
| 2175 | elfcpp::SHN_UNDEF, // large_common_shndx |
| 2176 | 0, // small_common_section_flags |
| 2177 | 0, // large_common_section_flags |
| 2178 | ".ARM.attributes", // attributes_section |
| 2179 | "aeabi" // attributes_vendor |
| 2180 | }; |
| 2181 | |
| 2182 | // Arm relocate functions class |
| 2183 | // |
| 2184 | |
| 2185 | template<bool big_endian> |
| 2186 | class Arm_relocate_functions : public Relocate_functions<32, big_endian> |
| 2187 | { |
| 2188 | public: |
| 2189 | typedef enum |
| 2190 | { |
| 2191 | STATUS_OKAY, // No error during relocation. |
| 2192 | STATUS_OVERFLOW, // Relocation oveflow. |
| 2193 | STATUS_BAD_RELOC // Relocation cannot be applied. |
| 2194 | } Status; |
| 2195 | |
| 2196 | private: |
| 2197 | typedef Relocate_functions<32, big_endian> Base; |
| 2198 | typedef Arm_relocate_functions<big_endian> This; |
| 2199 | |
| 2200 | // Encoding of imm16 argument for movt and movw ARM instructions |
| 2201 | // from ARM ARM: |
| 2202 | // |
| 2203 | // imm16 := imm4 | imm12 |
| 2204 | // |
| 2205 | // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0 |
| 2206 | // +-------+---------------+-------+-------+-----------------------+ |
| 2207 | // | | |imm4 | |imm12 | |
| 2208 | // +-------+---------------+-------+-------+-----------------------+ |
| 2209 | |
| 2210 | // Extract the relocation addend from VAL based on the ARM |
| 2211 | // instruction encoding described above. |
| 2212 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 2213 | extract_arm_movw_movt_addend( |
| 2214 | typename elfcpp::Swap<32, big_endian>::Valtype val) |
| 2215 | { |
| 2216 | // According to the Elf ABI for ARM Architecture the immediate |
| 2217 | // field is sign-extended to form the addend. |
| 2218 | return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff)); |
| 2219 | } |
| 2220 | |
| 2221 | // Insert X into VAL based on the ARM instruction encoding described |
| 2222 | // above. |
| 2223 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 2224 | insert_val_arm_movw_movt( |
| 2225 | typename elfcpp::Swap<32, big_endian>::Valtype val, |
| 2226 | typename elfcpp::Swap<32, big_endian>::Valtype x) |
| 2227 | { |
| 2228 | val &= 0xfff0f000; |
| 2229 | val |= x & 0x0fff; |
| 2230 | val |= (x & 0xf000) << 4; |
| 2231 | return val; |
| 2232 | } |
| 2233 | |
| 2234 | // Encoding of imm16 argument for movt and movw Thumb2 instructions |
| 2235 | // from ARM ARM: |
| 2236 | // |
| 2237 | // imm16 := imm4 | i | imm3 | imm8 |
| 2238 | // |
| 2239 | // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0 |
| 2240 | // +---------+-+-----------+-------++-+-----+-------+---------------+ |
| 2241 | // | |i| |imm4 || |imm3 | |imm8 | |
| 2242 | // +---------+-+-----------+-------++-+-----+-------+---------------+ |
| 2243 | |
| 2244 | // Extract the relocation addend from VAL based on the Thumb2 |
| 2245 | // instruction encoding described above. |
| 2246 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 2247 | extract_thumb_movw_movt_addend( |
| 2248 | typename elfcpp::Swap<32, big_endian>::Valtype val) |
| 2249 | { |
| 2250 | // According to the Elf ABI for ARM Architecture the immediate |
| 2251 | // field is sign-extended to form the addend. |
| 2252 | return utils::sign_extend<16>(((val >> 4) & 0xf000) |
| 2253 | | ((val >> 15) & 0x0800) |
| 2254 | | ((val >> 4) & 0x0700) |
| 2255 | | (val & 0x00ff)); |
| 2256 | } |
| 2257 | |
| 2258 | // Insert X into VAL based on the Thumb2 instruction encoding |
| 2259 | // described above. |
| 2260 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 2261 | insert_val_thumb_movw_movt( |
| 2262 | typename elfcpp::Swap<32, big_endian>::Valtype val, |
| 2263 | typename elfcpp::Swap<32, big_endian>::Valtype x) |
| 2264 | { |
| 2265 | val &= 0xfbf08f00; |
| 2266 | val |= (x & 0xf000) << 4; |
| 2267 | val |= (x & 0x0800) << 15; |
| 2268 | val |= (x & 0x0700) << 4; |
| 2269 | val |= (x & 0x00ff); |
| 2270 | return val; |
| 2271 | } |
| 2272 | |
| 2273 | // Handle ARM long branches. |
| 2274 | static typename This::Status |
| 2275 | arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*, |
| 2276 | unsigned char *, const Sized_symbol<32>*, |
| 2277 | const Arm_relobj<big_endian>*, unsigned int, |
| 2278 | const Symbol_value<32>*, Arm_address, Arm_address, bool); |
| 2279 | |
| 2280 | // Handle THUMB long branches. |
| 2281 | static typename This::Status |
| 2282 | thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*, |
| 2283 | unsigned char *, const Sized_symbol<32>*, |
| 2284 | const Arm_relobj<big_endian>*, unsigned int, |
| 2285 | const Symbol_value<32>*, Arm_address, Arm_address, bool); |
| 2286 | |
| 2287 | public: |
| 2288 | |
| 2289 | // Return the branch offset of a 32-bit THUMB branch. |
| 2290 | static inline int32_t |
| 2291 | thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn) |
| 2292 | { |
| 2293 | // We use the Thumb-2 encoding (backwards compatible with Thumb-1) |
| 2294 | // involving the J1 and J2 bits. |
| 2295 | uint32_t s = (upper_insn & (1U << 10)) >> 10; |
| 2296 | uint32_t upper = upper_insn & 0x3ffU; |
| 2297 | uint32_t lower = lower_insn & 0x7ffU; |
| 2298 | uint32_t j1 = (lower_insn & (1U << 13)) >> 13; |
| 2299 | uint32_t j2 = (lower_insn & (1U << 11)) >> 11; |
| 2300 | uint32_t i1 = j1 ^ s ? 0 : 1; |
| 2301 | uint32_t i2 = j2 ^ s ? 0 : 1; |
| 2302 | |
| 2303 | return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22) |
| 2304 | | (upper << 12) | (lower << 1)); |
| 2305 | } |
| 2306 | |
| 2307 | // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction. |
| 2308 | // UPPER_INSN is the original upper instruction of the branch. Caller is |
| 2309 | // responsible for overflow checking and BLX offset adjustment. |
| 2310 | static inline uint16_t |
| 2311 | thumb32_branch_upper(uint16_t upper_insn, int32_t offset) |
| 2312 | { |
| 2313 | uint32_t s = offset < 0 ? 1 : 0; |
| 2314 | uint32_t bits = static_cast<uint32_t>(offset); |
| 2315 | return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10); |
| 2316 | } |
| 2317 | |
| 2318 | // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction. |
| 2319 | // LOWER_INSN is the original lower instruction of the branch. Caller is |
| 2320 | // responsible for overflow checking and BLX offset adjustment. |
| 2321 | static inline uint16_t |
| 2322 | thumb32_branch_lower(uint16_t lower_insn, int32_t offset) |
| 2323 | { |
| 2324 | uint32_t s = offset < 0 ? 1 : 0; |
| 2325 | uint32_t bits = static_cast<uint32_t>(offset); |
| 2326 | return ((lower_insn & ~0x2fffU) |
| 2327 | | ((((bits >> 23) & 1) ^ !s) << 13) |
| 2328 | | ((((bits >> 22) & 1) ^ !s) << 11) |
| 2329 | | ((bits >> 1) & 0x7ffU)); |
| 2330 | } |
| 2331 | |
| 2332 | // Return the branch offset of a 32-bit THUMB conditional branch. |
| 2333 | static inline int32_t |
| 2334 | thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn) |
| 2335 | { |
| 2336 | uint32_t s = (upper_insn & 0x0400U) >> 10; |
| 2337 | uint32_t j1 = (lower_insn & 0x2000U) >> 13; |
| 2338 | uint32_t j2 = (lower_insn & 0x0800U) >> 11; |
| 2339 | uint32_t lower = (lower_insn & 0x07ffU); |
| 2340 | uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU); |
| 2341 | |
| 2342 | return utils::sign_extend<21>((upper << 12) | (lower << 1)); |
| 2343 | } |
| 2344 | |
| 2345 | // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper |
| 2346 | // instruction. UPPER_INSN is the original upper instruction of the branch. |
| 2347 | // Caller is responsible for overflow checking. |
| 2348 | static inline uint16_t |
| 2349 | thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset) |
| 2350 | { |
| 2351 | uint32_t s = offset < 0 ? 1 : 0; |
| 2352 | uint32_t bits = static_cast<uint32_t>(offset); |
| 2353 | return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12); |
| 2354 | } |
| 2355 | |
| 2356 | // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower |
| 2357 | // instruction. LOWER_INSN is the original lower instruction of the branch. |
| 2358 | // Caller is reponsible for overflow checking. |
| 2359 | static inline uint16_t |
| 2360 | thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset) |
| 2361 | { |
| 2362 | uint32_t bits = static_cast<uint32_t>(offset); |
| 2363 | uint32_t j2 = (bits & 0x00080000U) >> 19; |
| 2364 | uint32_t j1 = (bits & 0x00040000U) >> 18; |
| 2365 | uint32_t lo = (bits & 0x00000ffeU) >> 1; |
| 2366 | |
| 2367 | return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo; |
| 2368 | } |
| 2369 | |
| 2370 | // R_ARM_ABS8: S + A |
| 2371 | static inline typename This::Status |
| 2372 | abs8(unsigned char *view, |
| 2373 | const Sized_relobj<32, big_endian>* object, |
| 2374 | const Symbol_value<32>* psymval) |
| 2375 | { |
| 2376 | typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype; |
| 2377 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2378 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2379 | Valtype val = elfcpp::Swap<8, big_endian>::readval(wv); |
| 2380 | Reltype addend = utils::sign_extend<8>(val); |
| 2381 | Reltype x = psymval->value(object, addend); |
| 2382 | val = utils::bit_select(val, x, 0xffU); |
| 2383 | elfcpp::Swap<8, big_endian>::writeval(wv, val); |
| 2384 | return (utils::has_signed_unsigned_overflow<8>(x) |
| 2385 | ? This::STATUS_OVERFLOW |
| 2386 | : This::STATUS_OKAY); |
| 2387 | } |
| 2388 | |
| 2389 | // R_ARM_THM_ABS5: S + A |
| 2390 | static inline typename This::Status |
| 2391 | thm_abs5(unsigned char *view, |
| 2392 | const Sized_relobj<32, big_endian>* object, |
| 2393 | const Symbol_value<32>* psymval) |
| 2394 | { |
| 2395 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2396 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2397 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2398 | Valtype val = elfcpp::Swap<16, big_endian>::readval(wv); |
| 2399 | Reltype addend = (val & 0x7e0U) >> 6; |
| 2400 | Reltype x = psymval->value(object, addend); |
| 2401 | val = utils::bit_select(val, x << 6, 0x7e0U); |
| 2402 | elfcpp::Swap<16, big_endian>::writeval(wv, val); |
| 2403 | return (utils::has_overflow<5>(x) |
| 2404 | ? This::STATUS_OVERFLOW |
| 2405 | : This::STATUS_OKAY); |
| 2406 | } |
| 2407 | |
| 2408 | // R_ARM_ABS12: S + A |
| 2409 | static inline typename This::Status |
| 2410 | abs12(unsigned char *view, |
| 2411 | const Sized_relobj<32, big_endian>* object, |
| 2412 | const Symbol_value<32>* psymval) |
| 2413 | { |
| 2414 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2415 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2416 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2417 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2418 | Reltype addend = val & 0x0fffU; |
| 2419 | Reltype x = psymval->value(object, addend); |
| 2420 | val = utils::bit_select(val, x, 0x0fffU); |
| 2421 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2422 | return (utils::has_overflow<12>(x) |
| 2423 | ? This::STATUS_OVERFLOW |
| 2424 | : This::STATUS_OKAY); |
| 2425 | } |
| 2426 | |
| 2427 | // R_ARM_ABS16: S + A |
| 2428 | static inline typename This::Status |
| 2429 | abs16(unsigned char *view, |
| 2430 | const Sized_relobj<32, big_endian>* object, |
| 2431 | const Symbol_value<32>* psymval) |
| 2432 | { |
| 2433 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2434 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2435 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2436 | Valtype val = elfcpp::Swap<16, big_endian>::readval(wv); |
| 2437 | Reltype addend = utils::sign_extend<16>(val); |
| 2438 | Reltype x = psymval->value(object, addend); |
| 2439 | val = utils::bit_select(val, x, 0xffffU); |
| 2440 | elfcpp::Swap<16, big_endian>::writeval(wv, val); |
| 2441 | return (utils::has_signed_unsigned_overflow<16>(x) |
| 2442 | ? This::STATUS_OVERFLOW |
| 2443 | : This::STATUS_OKAY); |
| 2444 | } |
| 2445 | |
| 2446 | // R_ARM_ABS32: (S + A) | T |
| 2447 | static inline typename This::Status |
| 2448 | abs32(unsigned char *view, |
| 2449 | const Sized_relobj<32, big_endian>* object, |
| 2450 | const Symbol_value<32>* psymval, |
| 2451 | Arm_address thumb_bit) |
| 2452 | { |
| 2453 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2454 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2455 | Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2456 | Valtype x = psymval->value(object, addend) | thumb_bit; |
| 2457 | elfcpp::Swap<32, big_endian>::writeval(wv, x); |
| 2458 | return This::STATUS_OKAY; |
| 2459 | } |
| 2460 | |
| 2461 | // R_ARM_REL32: (S + A) | T - P |
| 2462 | static inline typename This::Status |
| 2463 | rel32(unsigned char *view, |
| 2464 | const Sized_relobj<32, big_endian>* object, |
| 2465 | const Symbol_value<32>* psymval, |
| 2466 | Arm_address address, |
| 2467 | Arm_address thumb_bit) |
| 2468 | { |
| 2469 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2470 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2471 | Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2472 | Valtype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 2473 | elfcpp::Swap<32, big_endian>::writeval(wv, x); |
| 2474 | return This::STATUS_OKAY; |
| 2475 | } |
| 2476 | |
| 2477 | // R_ARM_THM_CALL: (S + A) | T - P |
| 2478 | static inline typename This::Status |
| 2479 | thm_call(const Relocate_info<32, big_endian>* relinfo, unsigned char *view, |
| 2480 | const Sized_symbol<32>* gsym, const Arm_relobj<big_endian>* object, |
| 2481 | unsigned int r_sym, const Symbol_value<32>* psymval, |
| 2482 | Arm_address address, Arm_address thumb_bit, |
| 2483 | bool is_weakly_undefined_without_plt) |
| 2484 | { |
| 2485 | return thumb_branch_common(elfcpp::R_ARM_THM_CALL, relinfo, view, gsym, |
| 2486 | object, r_sym, psymval, address, thumb_bit, |
| 2487 | is_weakly_undefined_without_plt); |
| 2488 | } |
| 2489 | |
| 2490 | // R_ARM_THM_JUMP24: (S + A) | T - P |
| 2491 | static inline typename This::Status |
| 2492 | thm_jump24(const Relocate_info<32, big_endian>* relinfo, unsigned char *view, |
| 2493 | const Sized_symbol<32>* gsym, const Arm_relobj<big_endian>* object, |
| 2494 | unsigned int r_sym, const Symbol_value<32>* psymval, |
| 2495 | Arm_address address, Arm_address thumb_bit, |
| 2496 | bool is_weakly_undefined_without_plt) |
| 2497 | { |
| 2498 | return thumb_branch_common(elfcpp::R_ARM_THM_JUMP24, relinfo, view, gsym, |
| 2499 | object, r_sym, psymval, address, thumb_bit, |
| 2500 | is_weakly_undefined_without_plt); |
| 2501 | } |
| 2502 | |
| 2503 | // R_ARM_THM_JUMP24: (S + A) | T - P |
| 2504 | static typename This::Status |
| 2505 | thm_jump19(unsigned char *view, const Arm_relobj<big_endian>* object, |
| 2506 | const Symbol_value<32>* psymval, Arm_address address, |
| 2507 | Arm_address thumb_bit); |
| 2508 | |
| 2509 | // R_ARM_THM_XPC22: (S + A) | T - P |
| 2510 | static inline typename This::Status |
| 2511 | thm_xpc22(const Relocate_info<32, big_endian>* relinfo, unsigned char *view, |
| 2512 | const Sized_symbol<32>* gsym, const Arm_relobj<big_endian>* object, |
| 2513 | unsigned int r_sym, const Symbol_value<32>* psymval, |
| 2514 | Arm_address address, Arm_address thumb_bit, |
| 2515 | bool is_weakly_undefined_without_plt) |
| 2516 | { |
| 2517 | return thumb_branch_common(elfcpp::R_ARM_THM_XPC22, relinfo, view, gsym, |
| 2518 | object, r_sym, psymval, address, thumb_bit, |
| 2519 | is_weakly_undefined_without_plt); |
| 2520 | } |
| 2521 | |
| 2522 | // R_ARM_THM_JUMP6: S + A – P |
| 2523 | static inline typename This::Status |
| 2524 | thm_jump6(unsigned char *view, |
| 2525 | const Sized_relobj<32, big_endian>* object, |
| 2526 | const Symbol_value<32>* psymval, |
| 2527 | Arm_address address) |
| 2528 | { |
| 2529 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2530 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype; |
| 2531 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2532 | Valtype val = elfcpp::Swap<16, big_endian>::readval(wv); |
| 2533 | // bit[9]:bit[7:3]:’0’ (mask: 0x02f8) |
| 2534 | Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2)); |
| 2535 | Reltype x = (psymval->value(object, addend) - address); |
| 2536 | val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2); |
| 2537 | elfcpp::Swap<16, big_endian>::writeval(wv, val); |
| 2538 | // CZB does only forward jumps. |
| 2539 | return ((x > 0x007e) |
| 2540 | ? This::STATUS_OVERFLOW |
| 2541 | : This::STATUS_OKAY); |
| 2542 | } |
| 2543 | |
| 2544 | // R_ARM_THM_JUMP8: S + A – P |
| 2545 | static inline typename This::Status |
| 2546 | thm_jump8(unsigned char *view, |
| 2547 | const Sized_relobj<32, big_endian>* object, |
| 2548 | const Symbol_value<32>* psymval, |
| 2549 | Arm_address address) |
| 2550 | { |
| 2551 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2552 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype; |
| 2553 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2554 | Valtype val = elfcpp::Swap<16, big_endian>::readval(wv); |
| 2555 | Reltype addend = utils::sign_extend<8>((val & 0x00ff) << 1); |
| 2556 | Reltype x = (psymval->value(object, addend) - address); |
| 2557 | elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xff00) | ((x & 0x01fe) >> 1)); |
| 2558 | return (utils::has_overflow<8>(x) |
| 2559 | ? This::STATUS_OVERFLOW |
| 2560 | : This::STATUS_OKAY); |
| 2561 | } |
| 2562 | |
| 2563 | // R_ARM_THM_JUMP11: S + A – P |
| 2564 | static inline typename This::Status |
| 2565 | thm_jump11(unsigned char *view, |
| 2566 | const Sized_relobj<32, big_endian>* object, |
| 2567 | const Symbol_value<32>* psymval, |
| 2568 | Arm_address address) |
| 2569 | { |
| 2570 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2571 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype; |
| 2572 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2573 | Valtype val = elfcpp::Swap<16, big_endian>::readval(wv); |
| 2574 | Reltype addend = utils::sign_extend<11>((val & 0x07ff) << 1); |
| 2575 | Reltype x = (psymval->value(object, addend) - address); |
| 2576 | elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xf800) | ((x & 0x0ffe) >> 1)); |
| 2577 | return (utils::has_overflow<11>(x) |
| 2578 | ? This::STATUS_OVERFLOW |
| 2579 | : This::STATUS_OKAY); |
| 2580 | } |
| 2581 | |
| 2582 | // R_ARM_BASE_PREL: B(S) + A - P |
| 2583 | static inline typename This::Status |
| 2584 | base_prel(unsigned char* view, |
| 2585 | Arm_address origin, |
| 2586 | Arm_address address) |
| 2587 | { |
| 2588 | Base::rel32(view, origin - address); |
| 2589 | return STATUS_OKAY; |
| 2590 | } |
| 2591 | |
| 2592 | // R_ARM_BASE_ABS: B(S) + A |
| 2593 | static inline typename This::Status |
| 2594 | base_abs(unsigned char* view, |
| 2595 | Arm_address origin) |
| 2596 | { |
| 2597 | Base::rel32(view, origin); |
| 2598 | return STATUS_OKAY; |
| 2599 | } |
| 2600 | |
| 2601 | // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG |
| 2602 | static inline typename This::Status |
| 2603 | got_brel(unsigned char* view, |
| 2604 | typename elfcpp::Swap<32, big_endian>::Valtype got_offset) |
| 2605 | { |
| 2606 | Base::rel32(view, got_offset); |
| 2607 | return This::STATUS_OKAY; |
| 2608 | } |
| 2609 | |
| 2610 | // R_ARM_GOT_PREL: GOT(S) + A - P |
| 2611 | static inline typename This::Status |
| 2612 | got_prel(unsigned char *view, |
| 2613 | Arm_address got_entry, |
| 2614 | Arm_address address) |
| 2615 | { |
| 2616 | Base::rel32(view, got_entry - address); |
| 2617 | return This::STATUS_OKAY; |
| 2618 | } |
| 2619 | |
| 2620 | // R_ARM_PLT32: (S + A) | T - P |
| 2621 | static inline typename This::Status |
| 2622 | plt32(const Relocate_info<32, big_endian>* relinfo, |
| 2623 | unsigned char *view, |
| 2624 | const Sized_symbol<32>* gsym, |
| 2625 | const Arm_relobj<big_endian>* object, |
| 2626 | unsigned int r_sym, |
| 2627 | const Symbol_value<32>* psymval, |
| 2628 | Arm_address address, |
| 2629 | Arm_address thumb_bit, |
| 2630 | bool is_weakly_undefined_without_plt) |
| 2631 | { |
| 2632 | return arm_branch_common(elfcpp::R_ARM_PLT32, relinfo, view, gsym, |
| 2633 | object, r_sym, psymval, address, thumb_bit, |
| 2634 | is_weakly_undefined_without_plt); |
| 2635 | } |
| 2636 | |
| 2637 | // R_ARM_XPC25: (S + A) | T - P |
| 2638 | static inline typename This::Status |
| 2639 | xpc25(const Relocate_info<32, big_endian>* relinfo, |
| 2640 | unsigned char *view, |
| 2641 | const Sized_symbol<32>* gsym, |
| 2642 | const Arm_relobj<big_endian>* object, |
| 2643 | unsigned int r_sym, |
| 2644 | const Symbol_value<32>* psymval, |
| 2645 | Arm_address address, |
| 2646 | Arm_address thumb_bit, |
| 2647 | bool is_weakly_undefined_without_plt) |
| 2648 | { |
| 2649 | return arm_branch_common(elfcpp::R_ARM_XPC25, relinfo, view, gsym, |
| 2650 | object, r_sym, psymval, address, thumb_bit, |
| 2651 | is_weakly_undefined_without_plt); |
| 2652 | } |
| 2653 | |
| 2654 | // R_ARM_CALL: (S + A) | T - P |
| 2655 | static inline typename This::Status |
| 2656 | call(const Relocate_info<32, big_endian>* relinfo, |
| 2657 | unsigned char *view, |
| 2658 | const Sized_symbol<32>* gsym, |
| 2659 | const Arm_relobj<big_endian>* object, |
| 2660 | unsigned int r_sym, |
| 2661 | const Symbol_value<32>* psymval, |
| 2662 | Arm_address address, |
| 2663 | Arm_address thumb_bit, |
| 2664 | bool is_weakly_undefined_without_plt) |
| 2665 | { |
| 2666 | return arm_branch_common(elfcpp::R_ARM_CALL, relinfo, view, gsym, |
| 2667 | object, r_sym, psymval, address, thumb_bit, |
| 2668 | is_weakly_undefined_without_plt); |
| 2669 | } |
| 2670 | |
| 2671 | // R_ARM_JUMP24: (S + A) | T - P |
| 2672 | static inline typename This::Status |
| 2673 | jump24(const Relocate_info<32, big_endian>* relinfo, |
| 2674 | unsigned char *view, |
| 2675 | const Sized_symbol<32>* gsym, |
| 2676 | const Arm_relobj<big_endian>* object, |
| 2677 | unsigned int r_sym, |
| 2678 | const Symbol_value<32>* psymval, |
| 2679 | Arm_address address, |
| 2680 | Arm_address thumb_bit, |
| 2681 | bool is_weakly_undefined_without_plt) |
| 2682 | { |
| 2683 | return arm_branch_common(elfcpp::R_ARM_JUMP24, relinfo, view, gsym, |
| 2684 | object, r_sym, psymval, address, thumb_bit, |
| 2685 | is_weakly_undefined_without_plt); |
| 2686 | } |
| 2687 | |
| 2688 | // R_ARM_PREL: (S + A) | T - P |
| 2689 | static inline typename This::Status |
| 2690 | prel31(unsigned char *view, |
| 2691 | const Sized_relobj<32, big_endian>* object, |
| 2692 | const Symbol_value<32>* psymval, |
| 2693 | Arm_address address, |
| 2694 | Arm_address thumb_bit) |
| 2695 | { |
| 2696 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2697 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2698 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2699 | Valtype addend = utils::sign_extend<31>(val); |
| 2700 | Valtype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 2701 | val = utils::bit_select(val, x, 0x7fffffffU); |
| 2702 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2703 | return (utils::has_overflow<31>(x) ? |
| 2704 | This::STATUS_OVERFLOW : This::STATUS_OKAY); |
| 2705 | } |
| 2706 | |
| 2707 | // R_ARM_MOVW_ABS_NC: (S + A) | T |
| 2708 | static inline typename This::Status |
| 2709 | movw_abs_nc(unsigned char *view, |
| 2710 | const Sized_relobj<32, big_endian>* object, |
| 2711 | const Symbol_value<32>* psymval, |
| 2712 | Arm_address thumb_bit) |
| 2713 | { |
| 2714 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2715 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2716 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2717 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2718 | Valtype x = psymval->value(object, addend) | thumb_bit; |
| 2719 | val = This::insert_val_arm_movw_movt(val, x); |
| 2720 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2721 | return This::STATUS_OKAY; |
| 2722 | } |
| 2723 | |
| 2724 | // R_ARM_MOVT_ABS: S + A |
| 2725 | static inline typename This::Status |
| 2726 | movt_abs(unsigned char *view, |
| 2727 | const Sized_relobj<32, big_endian>* object, |
| 2728 | const Symbol_value<32>* psymval) |
| 2729 | { |
| 2730 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2731 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2732 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2733 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2734 | Valtype x = psymval->value(object, addend) >> 16; |
| 2735 | val = This::insert_val_arm_movw_movt(val, x); |
| 2736 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2737 | return This::STATUS_OKAY; |
| 2738 | } |
| 2739 | |
| 2740 | // R_ARM_THM_MOVW_ABS_NC: S + A | T |
| 2741 | static inline typename This::Status |
| 2742 | thm_movw_abs_nc(unsigned char *view, |
| 2743 | const Sized_relobj<32, big_endian>* object, |
| 2744 | const Symbol_value<32>* psymval, |
| 2745 | Arm_address thumb_bit) |
| 2746 | { |
| 2747 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2748 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2749 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2750 | Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2751 | | elfcpp::Swap<16, big_endian>::readval(wv + 1)); |
| 2752 | Reltype addend = extract_thumb_movw_movt_addend(val); |
| 2753 | Reltype x = psymval->value(object, addend) | thumb_bit; |
| 2754 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2755 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2756 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2757 | return This::STATUS_OKAY; |
| 2758 | } |
| 2759 | |
| 2760 | // R_ARM_THM_MOVT_ABS: S + A |
| 2761 | static inline typename This::Status |
| 2762 | thm_movt_abs(unsigned char *view, |
| 2763 | const Sized_relobj<32, big_endian>* object, |
| 2764 | const Symbol_value<32>* psymval) |
| 2765 | { |
| 2766 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2767 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2768 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2769 | Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2770 | | elfcpp::Swap<16, big_endian>::readval(wv + 1)); |
| 2771 | Reltype addend = This::extract_thumb_movw_movt_addend(val); |
| 2772 | Reltype x = psymval->value(object, addend) >> 16; |
| 2773 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2774 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2775 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2776 | return This::STATUS_OKAY; |
| 2777 | } |
| 2778 | |
| 2779 | // R_ARM_MOVW_PREL_NC: (S + A) | T - P |
| 2780 | static inline typename This::Status |
| 2781 | movw_prel_nc(unsigned char *view, |
| 2782 | const Sized_relobj<32, big_endian>* object, |
| 2783 | const Symbol_value<32>* psymval, |
| 2784 | Arm_address address, |
| 2785 | Arm_address thumb_bit) |
| 2786 | { |
| 2787 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2788 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2789 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2790 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2791 | Valtype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 2792 | val = This::insert_val_arm_movw_movt(val, x); |
| 2793 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2794 | return This::STATUS_OKAY; |
| 2795 | } |
| 2796 | |
| 2797 | // R_ARM_MOVT_PREL: S + A - P |
| 2798 | static inline typename This::Status |
| 2799 | movt_prel(unsigned char *view, |
| 2800 | const Sized_relobj<32, big_endian>* object, |
| 2801 | const Symbol_value<32>* psymval, |
| 2802 | Arm_address address) |
| 2803 | { |
| 2804 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2805 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2806 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2807 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2808 | Valtype x = (psymval->value(object, addend) - address) >> 16; |
| 2809 | val = This::insert_val_arm_movw_movt(val, x); |
| 2810 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2811 | return This::STATUS_OKAY; |
| 2812 | } |
| 2813 | |
| 2814 | // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P |
| 2815 | static inline typename This::Status |
| 2816 | thm_movw_prel_nc(unsigned char *view, |
| 2817 | const Sized_relobj<32, big_endian>* object, |
| 2818 | const Symbol_value<32>* psymval, |
| 2819 | Arm_address address, |
| 2820 | Arm_address thumb_bit) |
| 2821 | { |
| 2822 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2823 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2824 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2825 | Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2826 | | elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 2827 | Reltype addend = This::extract_thumb_movw_movt_addend(val); |
| 2828 | Reltype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 2829 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2830 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2831 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2832 | return This::STATUS_OKAY; |
| 2833 | } |
| 2834 | |
| 2835 | // R_ARM_THM_MOVT_PREL: S + A - P |
| 2836 | static inline typename This::Status |
| 2837 | thm_movt_prel(unsigned char *view, |
| 2838 | const Sized_relobj<32, big_endian>* object, |
| 2839 | const Symbol_value<32>* psymval, |
| 2840 | Arm_address address) |
| 2841 | { |
| 2842 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2843 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2844 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2845 | Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2846 | | elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 2847 | Reltype addend = This::extract_thumb_movw_movt_addend(val); |
| 2848 | Reltype x = (psymval->value(object, addend) - address) >> 16; |
| 2849 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2850 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2851 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2852 | return This::STATUS_OKAY; |
| 2853 | } |
| 2854 | |
| 2855 | // R_ARM_V4BX |
| 2856 | static inline typename This::Status |
| 2857 | v4bx(const Relocate_info<32, big_endian>* relinfo, |
| 2858 | unsigned char *view, |
| 2859 | const Arm_relobj<big_endian>* object, |
| 2860 | const Arm_address address, |
| 2861 | const bool is_interworking) |
| 2862 | { |
| 2863 | |
| 2864 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2865 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2866 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2867 | |
| 2868 | // Ensure that we have a BX instruction. |
| 2869 | gold_assert((val & 0x0ffffff0) == 0x012fff10); |
| 2870 | const uint32_t reg = (val & 0xf); |
| 2871 | if (is_interworking && reg != 0xf) |
| 2872 | { |
| 2873 | Stub_table<big_endian>* stub_table = |
| 2874 | object->stub_table(relinfo->data_shndx); |
| 2875 | gold_assert(stub_table != NULL); |
| 2876 | |
| 2877 | Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg); |
| 2878 | gold_assert(stub != NULL); |
| 2879 | |
| 2880 | int32_t veneer_address = |
| 2881 | stub_table->address() + stub->offset() - 8 - address; |
| 2882 | gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET) |
| 2883 | && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET)); |
| 2884 | // Replace with a branch to veneer (B <addr>) |
| 2885 | val = (val & 0xf0000000) | 0x0a000000 |
| 2886 | | ((veneer_address >> 2) & 0x00ffffff); |
| 2887 | } |
| 2888 | else |
| 2889 | { |
| 2890 | // Preserve Rm (lowest four bits) and the condition code |
| 2891 | // (highest four bits). Other bits encode MOV PC,Rm. |
| 2892 | val = (val & 0xf000000f) | 0x01a0f000; |
| 2893 | } |
| 2894 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2895 | return This::STATUS_OKAY; |
| 2896 | } |
| 2897 | }; |
| 2898 | |
| 2899 | // Relocate ARM long branches. This handles relocation types |
| 2900 | // R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25. |
| 2901 | // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly |
| 2902 | // undefined and we do not use PLT in this relocation. In such a case, |
| 2903 | // the branch is converted into an NOP. |
| 2904 | |
| 2905 | template<bool big_endian> |
| 2906 | typename Arm_relocate_functions<big_endian>::Status |
| 2907 | Arm_relocate_functions<big_endian>::arm_branch_common( |
| 2908 | unsigned int r_type, |
| 2909 | const Relocate_info<32, big_endian>* relinfo, |
| 2910 | unsigned char *view, |
| 2911 | const Sized_symbol<32>* gsym, |
| 2912 | const Arm_relobj<big_endian>* object, |
| 2913 | unsigned int r_sym, |
| 2914 | const Symbol_value<32>* psymval, |
| 2915 | Arm_address address, |
| 2916 | Arm_address thumb_bit, |
| 2917 | bool is_weakly_undefined_without_plt) |
| 2918 | { |
| 2919 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2920 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2921 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2922 | |
| 2923 | bool insn_is_b = (((val >> 28) & 0xf) <= 0xe) |
| 2924 | && ((val & 0x0f000000UL) == 0x0a000000UL); |
| 2925 | bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL; |
| 2926 | bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe) |
| 2927 | && ((val & 0x0f000000UL) == 0x0b000000UL); |
| 2928 | bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL; |
| 2929 | bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL; |
| 2930 | |
| 2931 | // Check that the instruction is valid. |
| 2932 | if (r_type == elfcpp::R_ARM_CALL) |
| 2933 | { |
| 2934 | if (!insn_is_uncond_bl && !insn_is_blx) |
| 2935 | return This::STATUS_BAD_RELOC; |
| 2936 | } |
| 2937 | else if (r_type == elfcpp::R_ARM_JUMP24) |
| 2938 | { |
| 2939 | if (!insn_is_b && !insn_is_cond_bl) |
| 2940 | return This::STATUS_BAD_RELOC; |
| 2941 | } |
| 2942 | else if (r_type == elfcpp::R_ARM_PLT32) |
| 2943 | { |
| 2944 | if (!insn_is_any_branch) |
| 2945 | return This::STATUS_BAD_RELOC; |
| 2946 | } |
| 2947 | else if (r_type == elfcpp::R_ARM_XPC25) |
| 2948 | { |
| 2949 | // FIXME: AAELF document IH0044C does not say much about it other |
| 2950 | // than it being obsolete. |
| 2951 | if (!insn_is_any_branch) |
| 2952 | return This::STATUS_BAD_RELOC; |
| 2953 | } |
| 2954 | else |
| 2955 | gold_unreachable(); |
| 2956 | |
| 2957 | // A branch to an undefined weak symbol is turned into a jump to |
| 2958 | // the next instruction unless a PLT entry will be created. |
| 2959 | // Do the same for local undefined symbols. |
| 2960 | // The jump to the next instruction is optimized as a NOP depending |
| 2961 | // on the architecture. |
| 2962 | const Target_arm<big_endian>* arm_target = |
| 2963 | Target_arm<big_endian>::default_target(); |
| 2964 | if (is_weakly_undefined_without_plt) |
| 2965 | { |
| 2966 | Valtype cond = val & 0xf0000000U; |
| 2967 | if (arm_target->may_use_arm_nop()) |
| 2968 | val = cond | 0x0320f000; |
| 2969 | else |
| 2970 | val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0. |
| 2971 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2972 | return This::STATUS_OKAY; |
| 2973 | } |
| 2974 | |
| 2975 | Valtype addend = utils::sign_extend<26>(val << 2); |
| 2976 | Valtype branch_target = psymval->value(object, addend); |
| 2977 | int32_t branch_offset = branch_target - address; |
| 2978 | |
| 2979 | // We need a stub if the branch offset is too large or if we need |
| 2980 | // to switch mode. |
| 2981 | bool may_use_blx = arm_target->may_use_blx(); |
| 2982 | Reloc_stub* stub = NULL; |
| 2983 | if ((branch_offset > ARM_MAX_FWD_BRANCH_OFFSET) |
| 2984 | || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET) |
| 2985 | || ((thumb_bit != 0) && !(may_use_blx && r_type == elfcpp::R_ARM_CALL))) |
| 2986 | { |
| 2987 | Stub_type stub_type = |
| 2988 | Reloc_stub::stub_type_for_reloc(r_type, address, branch_target, |
| 2989 | (thumb_bit != 0)); |
| 2990 | if (stub_type != arm_stub_none) |
| 2991 | { |
| 2992 | Stub_table<big_endian>* stub_table = |
| 2993 | object->stub_table(relinfo->data_shndx); |
| 2994 | gold_assert(stub_table != NULL); |
| 2995 | |
| 2996 | Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend); |
| 2997 | stub = stub_table->find_reloc_stub(stub_key); |
| 2998 | gold_assert(stub != NULL); |
| 2999 | thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0; |
| 3000 | branch_target = stub_table->address() + stub->offset() + addend; |
| 3001 | branch_offset = branch_target - address; |
| 3002 | gold_assert((branch_offset <= ARM_MAX_FWD_BRANCH_OFFSET) |
| 3003 | && (branch_offset >= ARM_MAX_BWD_BRANCH_OFFSET)); |
| 3004 | } |
| 3005 | } |
| 3006 | |
| 3007 | // At this point, if we still need to switch mode, the instruction |
| 3008 | // must either be a BLX or a BL that can be converted to a BLX. |
| 3009 | if (thumb_bit != 0) |
| 3010 | { |
| 3011 | // Turn BL to BLX. |
| 3012 | gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL); |
| 3013 | val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23); |
| 3014 | } |
| 3015 | |
| 3016 | val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL); |
| 3017 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 3018 | return (utils::has_overflow<26>(branch_offset) |
| 3019 | ? This::STATUS_OVERFLOW : This::STATUS_OKAY); |
| 3020 | } |
| 3021 | |
| 3022 | // Relocate THUMB long branches. This handles relocation types |
| 3023 | // R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22. |
| 3024 | // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly |
| 3025 | // undefined and we do not use PLT in this relocation. In such a case, |
| 3026 | // the branch is converted into an NOP. |
| 3027 | |
| 3028 | template<bool big_endian> |
| 3029 | typename Arm_relocate_functions<big_endian>::Status |
| 3030 | Arm_relocate_functions<big_endian>::thumb_branch_common( |
| 3031 | unsigned int r_type, |
| 3032 | const Relocate_info<32, big_endian>* relinfo, |
| 3033 | unsigned char *view, |
| 3034 | const Sized_symbol<32>* gsym, |
| 3035 | const Arm_relobj<big_endian>* object, |
| 3036 | unsigned int r_sym, |
| 3037 | const Symbol_value<32>* psymval, |
| 3038 | Arm_address address, |
| 3039 | Arm_address thumb_bit, |
| 3040 | bool is_weakly_undefined_without_plt) |
| 3041 | { |
| 3042 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 3043 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 3044 | uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 3045 | uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 3046 | |
| 3047 | // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference |
| 3048 | // into account. |
| 3049 | bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U; |
| 3050 | bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U; |
| 3051 | |
| 3052 | // Check that the instruction is valid. |
| 3053 | if (r_type == elfcpp::R_ARM_THM_CALL) |
| 3054 | { |
| 3055 | if (!is_bl_insn && !is_blx_insn) |
| 3056 | return This::STATUS_BAD_RELOC; |
| 3057 | } |
| 3058 | else if (r_type == elfcpp::R_ARM_THM_JUMP24) |
| 3059 | { |
| 3060 | // This cannot be a BLX. |
| 3061 | if (!is_bl_insn) |
| 3062 | return This::STATUS_BAD_RELOC; |
| 3063 | } |
| 3064 | else if (r_type == elfcpp::R_ARM_THM_XPC22) |
| 3065 | { |
| 3066 | // Check for Thumb to Thumb call. |
| 3067 | if (!is_blx_insn) |
| 3068 | return This::STATUS_BAD_RELOC; |
| 3069 | if (thumb_bit != 0) |
| 3070 | { |
| 3071 | gold_warning(_("%s: Thumb BLX instruction targets " |
| 3072 | "thumb function '%s'."), |
| 3073 | object->name().c_str(), |
| 3074 | (gsym ? gsym->name() : "(local)")); |
| 3075 | // Convert BLX to BL. |
| 3076 | lower_insn |= 0x1000U; |
| 3077 | } |
| 3078 | } |
| 3079 | else |
| 3080 | gold_unreachable(); |
| 3081 | |
| 3082 | // A branch to an undefined weak symbol is turned into a jump to |
| 3083 | // the next instruction unless a PLT entry will be created. |
| 3084 | // The jump to the next instruction is optimized as a NOP.W for |
| 3085 | // Thumb-2 enabled architectures. |
| 3086 | const Target_arm<big_endian>* arm_target = |
| 3087 | Target_arm<big_endian>::default_target(); |
| 3088 | if (is_weakly_undefined_without_plt) |
| 3089 | { |
| 3090 | if (arm_target->may_use_thumb2_nop()) |
| 3091 | { |
| 3092 | elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af); |
| 3093 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000); |
| 3094 | } |
| 3095 | else |
| 3096 | { |
| 3097 | elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000); |
| 3098 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00); |
| 3099 | } |
| 3100 | return This::STATUS_OKAY; |
| 3101 | } |
| 3102 | |
| 3103 | int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn); |
| 3104 | Arm_address branch_target = psymval->value(object, addend); |
| 3105 | int32_t branch_offset = branch_target - address; |
| 3106 | |
| 3107 | // We need a stub if the branch offset is too large or if we need |
| 3108 | // to switch mode. |
| 3109 | bool may_use_blx = arm_target->may_use_blx(); |
| 3110 | bool thumb2 = arm_target->using_thumb2(); |
| 3111 | if ((!thumb2 |
| 3112 | && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET |
| 3113 | || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET))) |
| 3114 | || (thumb2 |
| 3115 | && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET |
| 3116 | || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET))) |
| 3117 | || ((thumb_bit == 0) |
| 3118 | && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx) |
| 3119 | || r_type == elfcpp::R_ARM_THM_JUMP24))) |
| 3120 | { |
| 3121 | Stub_type stub_type = |
| 3122 | Reloc_stub::stub_type_for_reloc(r_type, address, branch_target, |
| 3123 | (thumb_bit != 0)); |
| 3124 | if (stub_type != arm_stub_none) |
| 3125 | { |
| 3126 | Stub_table<big_endian>* stub_table = |
| 3127 | object->stub_table(relinfo->data_shndx); |
| 3128 | gold_assert(stub_table != NULL); |
| 3129 | |
| 3130 | Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend); |
| 3131 | Reloc_stub* stub = stub_table->find_reloc_stub(stub_key); |
| 3132 | gold_assert(stub != NULL); |
| 3133 | thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0; |
| 3134 | branch_target = stub_table->address() + stub->offset() + addend; |
| 3135 | branch_offset = branch_target - address; |
| 3136 | } |
| 3137 | } |
| 3138 | |
| 3139 | // At this point, if we still need to switch mode, the instruction |
| 3140 | // must either be a BLX or a BL that can be converted to a BLX. |
| 3141 | if (thumb_bit == 0) |
| 3142 | { |
| 3143 | gold_assert(may_use_blx |
| 3144 | && (r_type == elfcpp::R_ARM_THM_CALL |
| 3145 | || r_type == elfcpp::R_ARM_THM_XPC22)); |
| 3146 | // Make sure this is a BLX. |
| 3147 | lower_insn &= ~0x1000U; |
| 3148 | } |
| 3149 | else |
| 3150 | { |
| 3151 | // Make sure this is a BL. |
| 3152 | lower_insn |= 0x1000U; |
| 3153 | } |
| 3154 | |
| 3155 | if ((lower_insn & 0x5000U) == 0x4000U) |
| 3156 | // For a BLX instruction, make sure that the relocation is rounded up |
| 3157 | // to a word boundary. This follows the semantics of the instruction |
| 3158 | // which specifies that bit 1 of the target address will come from bit |
| 3159 | // 1 of the base address. |
| 3160 | branch_offset = (branch_offset + 2) & ~3; |
| 3161 | |
| 3162 | // Put BRANCH_OFFSET back into the insn. Assumes two's complement. |
| 3163 | // We use the Thumb-2 encoding, which is safe even if dealing with |
| 3164 | // a Thumb-1 instruction by virtue of our overflow check above. */ |
| 3165 | upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset); |
| 3166 | lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset); |
| 3167 | |
| 3168 | elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn); |
| 3169 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn); |
| 3170 | |
| 3171 | return ((thumb2 |
| 3172 | ? utils::has_overflow<25>(branch_offset) |
| 3173 | : utils::has_overflow<23>(branch_offset)) |
| 3174 | ? This::STATUS_OVERFLOW |
| 3175 | : This::STATUS_OKAY); |
| 3176 | } |
| 3177 | |
| 3178 | // Relocate THUMB-2 long conditional branches. |
| 3179 | // If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly |
| 3180 | // undefined and we do not use PLT in this relocation. In such a case, |
| 3181 | // the branch is converted into an NOP. |
| 3182 | |
| 3183 | template<bool big_endian> |
| 3184 | typename Arm_relocate_functions<big_endian>::Status |
| 3185 | Arm_relocate_functions<big_endian>::thm_jump19( |
| 3186 | unsigned char *view, |
| 3187 | const Arm_relobj<big_endian>* object, |
| 3188 | const Symbol_value<32>* psymval, |
| 3189 | Arm_address address, |
| 3190 | Arm_address thumb_bit) |
| 3191 | { |
| 3192 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 3193 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 3194 | uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 3195 | uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 3196 | int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn); |
| 3197 | |
| 3198 | Arm_address branch_target = psymval->value(object, addend); |
| 3199 | int32_t branch_offset = branch_target - address; |
| 3200 | |
| 3201 | // ??? Should handle interworking? GCC might someday try to |
| 3202 | // use this for tail calls. |
| 3203 | // FIXME: We do support thumb entry to PLT yet. |
| 3204 | if (thumb_bit == 0) |
| 3205 | { |
| 3206 | gold_error(_("conditional branch to PLT in THUMB-2 not supported yet.")); |
| 3207 | return This::STATUS_BAD_RELOC; |
| 3208 | } |
| 3209 | |
| 3210 | // Put RELOCATION back into the insn. |
| 3211 | upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset); |
| 3212 | lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset); |
| 3213 | |
| 3214 | // Put the relocated value back in the object file: |
| 3215 | elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn); |
| 3216 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn); |
| 3217 | |
| 3218 | return (utils::has_overflow<21>(branch_offset) |
| 3219 | ? This::STATUS_OVERFLOW |
| 3220 | : This::STATUS_OKAY); |
| 3221 | } |
| 3222 | |
| 3223 | // Get the GOT section, creating it if necessary. |
| 3224 | |
| 3225 | template<bool big_endian> |
| 3226 | Output_data_got<32, big_endian>* |
| 3227 | Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout) |
| 3228 | { |
| 3229 | if (this->got_ == NULL) |
| 3230 | { |
| 3231 | gold_assert(symtab != NULL && layout != NULL); |
| 3232 | |
| 3233 | this->got_ = new Output_data_got<32, big_endian>(); |
| 3234 | |
| 3235 | Output_section* os; |
| 3236 | os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, |
| 3237 | (elfcpp::SHF_ALLOC |
| 3238 | | elfcpp::SHF_WRITE), |
| 3239 | this->got_, false, true, true, |
| 3240 | false); |
| 3241 | |
| 3242 | // The old GNU linker creates a .got.plt section. We just |
| 3243 | // create another set of data in the .got section. Note that we |
| 3244 | // always create a PLT if we create a GOT, although the PLT |
| 3245 | // might be empty. |
| 3246 | this->got_plt_ = new Output_data_space(4, "** GOT PLT"); |
| 3247 | os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, |
| 3248 | (elfcpp::SHF_ALLOC |
| 3249 | | elfcpp::SHF_WRITE), |
| 3250 | this->got_plt_, false, false, |
| 3251 | false, true); |
| 3252 | |
| 3253 | // The first three entries are reserved. |
| 3254 | this->got_plt_->set_current_data_size(3 * 4); |
| 3255 | |
| 3256 | // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. |
| 3257 | symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL, |
| 3258 | Symbol_table::PREDEFINED, |
| 3259 | this->got_plt_, |
| 3260 | 0, 0, elfcpp::STT_OBJECT, |
| 3261 | elfcpp::STB_LOCAL, |
| 3262 | elfcpp::STV_HIDDEN, 0, |
| 3263 | false, false); |
| 3264 | } |
| 3265 | return this->got_; |
| 3266 | } |
| 3267 | |
| 3268 | // Get the dynamic reloc section, creating it if necessary. |
| 3269 | |
| 3270 | template<bool big_endian> |
| 3271 | typename Target_arm<big_endian>::Reloc_section* |
| 3272 | Target_arm<big_endian>::rel_dyn_section(Layout* layout) |
| 3273 | { |
| 3274 | if (this->rel_dyn_ == NULL) |
| 3275 | { |
| 3276 | gold_assert(layout != NULL); |
| 3277 | this->rel_dyn_ = new Reloc_section(parameters->options().combreloc()); |
| 3278 | layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL, |
| 3279 | elfcpp::SHF_ALLOC, this->rel_dyn_, true, |
| 3280 | false, false, false); |
| 3281 | } |
| 3282 | return this->rel_dyn_; |
| 3283 | } |
| 3284 | |
| 3285 | // Insn_template methods. |
| 3286 | |
| 3287 | // Return byte size of an instruction template. |
| 3288 | |
| 3289 | size_t |
| 3290 | Insn_template::size() const |
| 3291 | { |
| 3292 | switch (this->type()) |
| 3293 | { |
| 3294 | case THUMB16_TYPE: |
| 3295 | case THUMB16_SPECIAL_TYPE: |
| 3296 | return 2; |
| 3297 | case ARM_TYPE: |
| 3298 | case THUMB32_TYPE: |
| 3299 | case DATA_TYPE: |
| 3300 | return 4; |
| 3301 | default: |
| 3302 | gold_unreachable(); |
| 3303 | } |
| 3304 | } |
| 3305 | |
| 3306 | // Return alignment of an instruction template. |
| 3307 | |
| 3308 | unsigned |
| 3309 | Insn_template::alignment() const |
| 3310 | { |
| 3311 | switch (this->type()) |
| 3312 | { |
| 3313 | case THUMB16_TYPE: |
| 3314 | case THUMB16_SPECIAL_TYPE: |
| 3315 | case THUMB32_TYPE: |
| 3316 | return 2; |
| 3317 | case ARM_TYPE: |
| 3318 | case DATA_TYPE: |
| 3319 | return 4; |
| 3320 | default: |
| 3321 | gold_unreachable(); |
| 3322 | } |
| 3323 | } |
| 3324 | |
| 3325 | // Stub_template methods. |
| 3326 | |
| 3327 | Stub_template::Stub_template( |
| 3328 | Stub_type type, const Insn_template* insns, |
| 3329 | size_t insn_count) |
| 3330 | : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1), |
| 3331 | entry_in_thumb_mode_(false), relocs_() |
| 3332 | { |
| 3333 | off_t offset = 0; |
| 3334 | |
| 3335 | // Compute byte size and alignment of stub template. |
| 3336 | for (size_t i = 0; i < insn_count; i++) |
| 3337 | { |
| 3338 | unsigned insn_alignment = insns[i].alignment(); |
| 3339 | size_t insn_size = insns[i].size(); |
| 3340 | gold_assert((offset & (insn_alignment - 1)) == 0); |
| 3341 | this->alignment_ = std::max(this->alignment_, insn_alignment); |
| 3342 | switch (insns[i].type()) |
| 3343 | { |
| 3344 | case Insn_template::THUMB16_TYPE: |
| 3345 | case Insn_template::THUMB16_SPECIAL_TYPE: |
| 3346 | if (i == 0) |
| 3347 | this->entry_in_thumb_mode_ = true; |
| 3348 | break; |
| 3349 | |
| 3350 | case Insn_template::THUMB32_TYPE: |
| 3351 | if (insns[i].r_type() != elfcpp::R_ARM_NONE) |
| 3352 | this->relocs_.push_back(Reloc(i, offset)); |
| 3353 | if (i == 0) |
| 3354 | this->entry_in_thumb_mode_ = true; |
| 3355 | break; |
| 3356 | |
| 3357 | case Insn_template::ARM_TYPE: |
| 3358 | // Handle cases where the target is encoded within the |
| 3359 | // instruction. |
| 3360 | if (insns[i].r_type() == elfcpp::R_ARM_JUMP24) |
| 3361 | this->relocs_.push_back(Reloc(i, offset)); |
| 3362 | break; |
| 3363 | |
| 3364 | case Insn_template::DATA_TYPE: |
| 3365 | // Entry point cannot be data. |
| 3366 | gold_assert(i != 0); |
| 3367 | this->relocs_.push_back(Reloc(i, offset)); |
| 3368 | break; |
| 3369 | |
| 3370 | default: |
| 3371 | gold_unreachable(); |
| 3372 | } |
| 3373 | offset += insn_size; |
| 3374 | } |
| 3375 | this->size_ = offset; |
| 3376 | } |
| 3377 | |
| 3378 | // Stub methods. |
| 3379 | |
| 3380 | // Template to implement do_write for a specific target endianity. |
| 3381 | |
| 3382 | template<bool big_endian> |
| 3383 | void inline |
| 3384 | Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size) |
| 3385 | { |
| 3386 | const Stub_template* stub_template = this->stub_template(); |
| 3387 | const Insn_template* insns = stub_template->insns(); |
| 3388 | |
| 3389 | // FIXME: We do not handle BE8 encoding yet. |
| 3390 | unsigned char* pov = view; |
| 3391 | for (size_t i = 0; i < stub_template->insn_count(); i++) |
| 3392 | { |
| 3393 | switch (insns[i].type()) |
| 3394 | { |
| 3395 | case Insn_template::THUMB16_TYPE: |
| 3396 | elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff); |
| 3397 | break; |
| 3398 | case Insn_template::THUMB16_SPECIAL_TYPE: |
| 3399 | elfcpp::Swap<16, big_endian>::writeval( |
| 3400 | pov, |
| 3401 | this->thumb16_special(i)); |
| 3402 | break; |
| 3403 | case Insn_template::THUMB32_TYPE: |
| 3404 | { |
| 3405 | uint32_t hi = (insns[i].data() >> 16) & 0xffff; |
| 3406 | uint32_t lo = insns[i].data() & 0xffff; |
| 3407 | elfcpp::Swap<16, big_endian>::writeval(pov, hi); |
| 3408 | elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo); |
| 3409 | } |
| 3410 | break; |
| 3411 | case Insn_template::ARM_TYPE: |
| 3412 | case Insn_template::DATA_TYPE: |
| 3413 | elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data()); |
| 3414 | break; |
| 3415 | default: |
| 3416 | gold_unreachable(); |
| 3417 | } |
| 3418 | pov += insns[i].size(); |
| 3419 | } |
| 3420 | gold_assert(static_cast<section_size_type>(pov - view) == view_size); |
| 3421 | } |
| 3422 | |
| 3423 | // Reloc_stub::Key methods. |
| 3424 | |
| 3425 | // Dump a Key as a string for debugging. |
| 3426 | |
| 3427 | std::string |
| 3428 | Reloc_stub::Key::name() const |
| 3429 | { |
| 3430 | if (this->r_sym_ == invalid_index) |
| 3431 | { |
| 3432 | // Global symbol key name |
| 3433 | // <stub-type>:<symbol name>:<addend>. |
| 3434 | const std::string sym_name = this->u_.symbol->name(); |
| 3435 | // We need to print two hex number and two colons. So just add 100 bytes |
| 3436 | // to the symbol name size. |
| 3437 | size_t len = sym_name.size() + 100; |
| 3438 | char* buffer = new char[len]; |
| 3439 | int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_, |
| 3440 | sym_name.c_str(), this->addend_); |
| 3441 | gold_assert(c > 0 && c < static_cast<int>(len)); |
| 3442 | delete[] buffer; |
| 3443 | return std::string(buffer); |
| 3444 | } |
| 3445 | else |
| 3446 | { |
| 3447 | // local symbol key name |
| 3448 | // <stub-type>:<object>:<r_sym>:<addend>. |
| 3449 | const size_t len = 200; |
| 3450 | char buffer[len]; |
| 3451 | int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_, |
| 3452 | this->u_.relobj, this->r_sym_, this->addend_); |
| 3453 | gold_assert(c > 0 && c < static_cast<int>(len)); |
| 3454 | return std::string(buffer); |
| 3455 | } |
| 3456 | } |
| 3457 | |
| 3458 | // Reloc_stub methods. |
| 3459 | |
| 3460 | // Determine the type of stub needed, if any, for a relocation of R_TYPE at |
| 3461 | // LOCATION to DESTINATION. |
| 3462 | // This code is based on the arm_type_of_stub function in |
| 3463 | // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub |
| 3464 | // class simple. |
| 3465 | |
| 3466 | Stub_type |
| 3467 | Reloc_stub::stub_type_for_reloc( |
| 3468 | unsigned int r_type, |
| 3469 | Arm_address location, |
| 3470 | Arm_address destination, |
| 3471 | bool target_is_thumb) |
| 3472 | { |
| 3473 | Stub_type stub_type = arm_stub_none; |
| 3474 | |
| 3475 | // This is a bit ugly but we want to avoid using a templated class for |
| 3476 | // big and little endianities. |
| 3477 | bool may_use_blx; |
| 3478 | bool should_force_pic_veneer; |
| 3479 | bool thumb2; |
| 3480 | bool thumb_only; |
| 3481 | if (parameters->target().is_big_endian()) |
| 3482 | { |
| 3483 | const Target_arm<true>* big_endian_target = |
| 3484 | Target_arm<true>::default_target(); |
| 3485 | may_use_blx = big_endian_target->may_use_blx(); |
| 3486 | should_force_pic_veneer = big_endian_target->should_force_pic_veneer(); |
| 3487 | thumb2 = big_endian_target->using_thumb2(); |
| 3488 | thumb_only = big_endian_target->using_thumb_only(); |
| 3489 | } |
| 3490 | else |
| 3491 | { |
| 3492 | const Target_arm<false>* little_endian_target = |
| 3493 | Target_arm<false>::default_target(); |
| 3494 | may_use_blx = little_endian_target->may_use_blx(); |
| 3495 | should_force_pic_veneer = little_endian_target->should_force_pic_veneer(); |
| 3496 | thumb2 = little_endian_target->using_thumb2(); |
| 3497 | thumb_only = little_endian_target->using_thumb_only(); |
| 3498 | } |
| 3499 | |
| 3500 | int64_t branch_offset = (int64_t)destination - location; |
| 3501 | |
| 3502 | if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24) |
| 3503 | { |
| 3504 | // Handle cases where: |
| 3505 | // - this call goes too far (different Thumb/Thumb2 max |
| 3506 | // distance) |
| 3507 | // - it's a Thumb->Arm call and blx is not available, or it's a |
| 3508 | // Thumb->Arm branch (not bl). A stub is needed in this case. |
| 3509 | if ((!thumb2 |
| 3510 | && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET |
| 3511 | || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET))) |
| 3512 | || (thumb2 |
| 3513 | && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET |
| 3514 | || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET))) |
| 3515 | || ((!target_is_thumb) |
| 3516 | && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx) |
| 3517 | || (r_type == elfcpp::R_ARM_THM_JUMP24)))) |
| 3518 | { |
| 3519 | if (target_is_thumb) |
| 3520 | { |
| 3521 | // Thumb to thumb. |
| 3522 | if (!thumb_only) |
| 3523 | { |
| 3524 | stub_type = (parameters->options().shared() |
| 3525 | || should_force_pic_veneer) |
| 3526 | // PIC stubs. |
| 3527 | ? ((may_use_blx |
| 3528 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 3529 | // V5T and above. Stub starts with ARM code, so |
| 3530 | // we must be able to switch mode before |
| 3531 | // reaching it, which is only possible for 'bl' |
| 3532 | // (ie R_ARM_THM_CALL relocation). |
| 3533 | ? arm_stub_long_branch_any_thumb_pic |
| 3534 | // On V4T, use Thumb code only. |
| 3535 | : arm_stub_long_branch_v4t_thumb_thumb_pic) |
| 3536 | |
| 3537 | // non-PIC stubs. |
| 3538 | : ((may_use_blx |
| 3539 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 3540 | ? arm_stub_long_branch_any_any // V5T and above. |
| 3541 | : arm_stub_long_branch_v4t_thumb_thumb); // V4T. |
| 3542 | } |
| 3543 | else |
| 3544 | { |
| 3545 | stub_type = (parameters->options().shared() |
| 3546 | || should_force_pic_veneer) |
| 3547 | ? arm_stub_long_branch_thumb_only_pic // PIC stub. |
| 3548 | : arm_stub_long_branch_thumb_only; // non-PIC stub. |
| 3549 | } |
| 3550 | } |
| 3551 | else |
| 3552 | { |
| 3553 | // Thumb to arm. |
| 3554 | |
| 3555 | // FIXME: We should check that the input section is from an |
| 3556 | // object that has interwork enabled. |
| 3557 | |
| 3558 | stub_type = (parameters->options().shared() |
| 3559 | || should_force_pic_veneer) |
| 3560 | // PIC stubs. |
| 3561 | ? ((may_use_blx |
| 3562 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 3563 | ? arm_stub_long_branch_any_arm_pic // V5T and above. |
| 3564 | : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T. |
| 3565 | |
| 3566 | // non-PIC stubs. |
| 3567 | : ((may_use_blx |
| 3568 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 3569 | ? arm_stub_long_branch_any_any // V5T and above. |
| 3570 | : arm_stub_long_branch_v4t_thumb_arm); // V4T. |
| 3571 | |
| 3572 | // Handle v4t short branches. |
| 3573 | if ((stub_type == arm_stub_long_branch_v4t_thumb_arm) |
| 3574 | && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET) |
| 3575 | && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET)) |
| 3576 | stub_type = arm_stub_short_branch_v4t_thumb_arm; |
| 3577 | } |
| 3578 | } |
| 3579 | } |
| 3580 | else if (r_type == elfcpp::R_ARM_CALL |
| 3581 | || r_type == elfcpp::R_ARM_JUMP24 |
| 3582 | || r_type == elfcpp::R_ARM_PLT32) |
| 3583 | { |
| 3584 | if (target_is_thumb) |
| 3585 | { |
| 3586 | // Arm to thumb. |
| 3587 | |
| 3588 | // FIXME: We should check that the input section is from an |
| 3589 | // object that has interwork enabled. |
| 3590 | |
| 3591 | // We have an extra 2-bytes reach because of |
| 3592 | // the mode change (bit 24 (H) of BLX encoding). |
| 3593 | if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2) |
| 3594 | || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET) |
| 3595 | || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx) |
| 3596 | || (r_type == elfcpp::R_ARM_JUMP24) |
| 3597 | || (r_type == elfcpp::R_ARM_PLT32)) |
| 3598 | { |
| 3599 | stub_type = (parameters->options().shared() |
| 3600 | || should_force_pic_veneer) |
| 3601 | // PIC stubs. |
| 3602 | ? (may_use_blx |
| 3603 | ? arm_stub_long_branch_any_thumb_pic// V5T and above. |
| 3604 | : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub. |
| 3605 | |
| 3606 | // non-PIC stubs. |
| 3607 | : (may_use_blx |
| 3608 | ? arm_stub_long_branch_any_any // V5T and above. |
| 3609 | : arm_stub_long_branch_v4t_arm_thumb); // V4T. |
| 3610 | } |
| 3611 | } |
| 3612 | else |
| 3613 | { |
| 3614 | // Arm to arm. |
| 3615 | if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET |
| 3616 | || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)) |
| 3617 | { |
| 3618 | stub_type = (parameters->options().shared() |
| 3619 | || should_force_pic_veneer) |
| 3620 | ? arm_stub_long_branch_any_arm_pic // PIC stubs. |
| 3621 | : arm_stub_long_branch_any_any; /// non-PIC. |
| 3622 | } |
| 3623 | } |
| 3624 | } |
| 3625 | |
| 3626 | return stub_type; |
| 3627 | } |
| 3628 | |
| 3629 | // Cortex_a8_stub methods. |
| 3630 | |
| 3631 | // Return the instruction for a THUMB16_SPECIAL_TYPE instruction template. |
| 3632 | // I is the position of the instruction template in the stub template. |
| 3633 | |
| 3634 | uint16_t |
| 3635 | Cortex_a8_stub::do_thumb16_special(size_t i) |
| 3636 | { |
| 3637 | // The only use of this is to copy condition code from a conditional |
| 3638 | // branch being worked around to the corresponding conditional branch in |
| 3639 | // to the stub. |
| 3640 | gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond |
| 3641 | && i == 0); |
| 3642 | uint16_t data = this->stub_template()->insns()[i].data(); |
| 3643 | gold_assert((data & 0xff00U) == 0xd000U); |
| 3644 | data |= ((this->original_insn_ >> 22) & 0xf) << 8; |
| 3645 | return data; |
| 3646 | } |
| 3647 | |
| 3648 | // Stub_factory methods. |
| 3649 | |
| 3650 | Stub_factory::Stub_factory() |
| 3651 | { |
| 3652 | // The instruction template sequences are declared as static |
| 3653 | // objects and initialized first time the constructor runs. |
| 3654 | |
| 3655 | // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx |
| 3656 | // to reach the stub if necessary. |
| 3657 | static const Insn_template elf32_arm_stub_long_branch_any_any[] = |
| 3658 | { |
| 3659 | Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4] |
| 3660 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 3661 | // dcd R_ARM_ABS32(X) |
| 3662 | }; |
| 3663 | |
| 3664 | // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not |
| 3665 | // available. |
| 3666 | static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] = |
| 3667 | { |
| 3668 | Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0] |
| 3669 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 3670 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 3671 | // dcd R_ARM_ABS32(X) |
| 3672 | }; |
| 3673 | |
| 3674 | // Thumb -> Thumb long branch stub. Used on M-profile architectures. |
| 3675 | static const Insn_template elf32_arm_stub_long_branch_thumb_only[] = |
| 3676 | { |
| 3677 | Insn_template::thumb16_insn(0xb401), // push {r0} |
| 3678 | Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8] |
| 3679 | Insn_template::thumb16_insn(0x4684), // mov ip, r0 |
| 3680 | Insn_template::thumb16_insn(0xbc01), // pop {r0} |
| 3681 | Insn_template::thumb16_insn(0x4760), // bx ip |
| 3682 | Insn_template::thumb16_insn(0xbf00), // nop |
| 3683 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 3684 | // dcd R_ARM_ABS32(X) |
| 3685 | }; |
| 3686 | |
| 3687 | // V4T Thumb -> Thumb long branch stub. Using the stack is not |
| 3688 | // allowed. |
| 3689 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] = |
| 3690 | { |
| 3691 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 3692 | Insn_template::thumb16_insn(0x46c0), // nop |
| 3693 | Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0] |
| 3694 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 3695 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 3696 | // dcd R_ARM_ABS32(X) |
| 3697 | }; |
| 3698 | |
| 3699 | // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not |
| 3700 | // available. |
| 3701 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] = |
| 3702 | { |
| 3703 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 3704 | Insn_template::thumb16_insn(0x46c0), // nop |
| 3705 | Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4] |
| 3706 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 3707 | // dcd R_ARM_ABS32(X) |
| 3708 | }; |
| 3709 | |
| 3710 | // V4T Thumb -> ARM short branch stub. Shorter variant of the above |
| 3711 | // one, when the destination is close enough. |
| 3712 | static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] = |
| 3713 | { |
| 3714 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 3715 | Insn_template::thumb16_insn(0x46c0), // nop |
| 3716 | Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8) |
| 3717 | }; |
| 3718 | |
| 3719 | // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use |
| 3720 | // blx to reach the stub if necessary. |
| 3721 | static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] = |
| 3722 | { |
| 3723 | Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc] |
| 3724 | Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip |
| 3725 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4), |
| 3726 | // dcd R_ARM_REL32(X-4) |
| 3727 | }; |
| 3728 | |
| 3729 | // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use |
| 3730 | // blx to reach the stub if necessary. We can not add into pc; |
| 3731 | // it is not guaranteed to mode switch (different in ARMv6 and |
| 3732 | // ARMv7). |
| 3733 | static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] = |
| 3734 | { |
| 3735 | Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4] |
| 3736 | Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip |
| 3737 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 3738 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0), |
| 3739 | // dcd R_ARM_REL32(X) |
| 3740 | }; |
| 3741 | |
| 3742 | // V4T ARM -> ARM long branch stub, PIC. |
| 3743 | static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] = |
| 3744 | { |
| 3745 | Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4] |
| 3746 | Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip |
| 3747 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 3748 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0), |
| 3749 | // dcd R_ARM_REL32(X) |
| 3750 | }; |
| 3751 | |
| 3752 | // V4T Thumb -> ARM long branch stub, PIC. |
| 3753 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] = |
| 3754 | { |
| 3755 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 3756 | Insn_template::thumb16_insn(0x46c0), // nop |
| 3757 | Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0] |
| 3758 | Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc |
| 3759 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4), |
| 3760 | // dcd R_ARM_REL32(X) |
| 3761 | }; |
| 3762 | |
| 3763 | // Thumb -> Thumb long branch stub, PIC. Used on M-profile |
| 3764 | // architectures. |
| 3765 | static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] = |
| 3766 | { |
| 3767 | Insn_template::thumb16_insn(0xb401), // push {r0} |
| 3768 | Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8] |
| 3769 | Insn_template::thumb16_insn(0x46fc), // mov ip, pc |
| 3770 | Insn_template::thumb16_insn(0x4484), // add ip, r0 |
| 3771 | Insn_template::thumb16_insn(0xbc01), // pop {r0} |
| 3772 | Insn_template::thumb16_insn(0x4760), // bx ip |
| 3773 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4), |
| 3774 | // dcd R_ARM_REL32(X) |
| 3775 | }; |
| 3776 | |
| 3777 | // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not |
| 3778 | // allowed. |
| 3779 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] = |
| 3780 | { |
| 3781 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 3782 | Insn_template::thumb16_insn(0x46c0), // nop |
| 3783 | Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4] |
| 3784 | Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip |
| 3785 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 3786 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0), |
| 3787 | // dcd R_ARM_REL32(X) |
| 3788 | }; |
| 3789 | |
| 3790 | // Cortex-A8 erratum-workaround stubs. |
| 3791 | |
| 3792 | // Stub used for conditional branches (which may be beyond +/-1MB away, |
| 3793 | // so we can't use a conditional branch to reach this stub). |
| 3794 | |
| 3795 | // original code: |
| 3796 | // |
| 3797 | // b<cond> X |
| 3798 | // after: |
| 3799 | // |
| 3800 | static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] = |
| 3801 | { |
| 3802 | Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true |
| 3803 | Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after |
| 3804 | Insn_template::thumb32_b_insn(0xf000b800, -4) // true: |
| 3805 | // b.w X |
| 3806 | }; |
| 3807 | |
| 3808 | // Stub used for b.w and bl.w instructions. |
| 3809 | |
| 3810 | static const Insn_template elf32_arm_stub_a8_veneer_b[] = |
| 3811 | { |
| 3812 | Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest |
| 3813 | }; |
| 3814 | |
| 3815 | static const Insn_template elf32_arm_stub_a8_veneer_bl[] = |
| 3816 | { |
| 3817 | Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest |
| 3818 | }; |
| 3819 | |
| 3820 | // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w |
| 3821 | // instruction (which switches to ARM mode) to point to this stub. Jump to |
| 3822 | // the real destination using an ARM-mode branch. |
| 3823 | static const Insn_template elf32_arm_stub_a8_veneer_blx[] = |
| 3824 | { |
| 3825 | Insn_template::arm_rel_insn(0xea000000, -8) // b dest |
| 3826 | }; |
| 3827 | |
| 3828 | // Stub used to provide an interworking for R_ARM_V4BX relocation |
| 3829 | // (bx r[n] instruction). |
| 3830 | static const Insn_template elf32_arm_stub_v4_veneer_bx[] = |
| 3831 | { |
| 3832 | Insn_template::arm_insn(0xe3100001), // tst r<n>, #1 |
| 3833 | Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n> |
| 3834 | Insn_template::arm_insn(0xe12fff10) // bx r<n> |
| 3835 | }; |
| 3836 | |
| 3837 | // Fill in the stub template look-up table. Stub templates are constructed |
| 3838 | // per instance of Stub_factory for fast look-up without locking |
| 3839 | // in a thread-enabled environment. |
| 3840 | |
| 3841 | this->stub_templates_[arm_stub_none] = |
| 3842 | new Stub_template(arm_stub_none, NULL, 0); |
| 3843 | |
| 3844 | #define DEF_STUB(x) \ |
| 3845 | do \ |
| 3846 | { \ |
| 3847 | size_t array_size \ |
| 3848 | = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \ |
| 3849 | Stub_type type = arm_stub_##x; \ |
| 3850 | this->stub_templates_[type] = \ |
| 3851 | new Stub_template(type, elf32_arm_stub_##x, array_size); \ |
| 3852 | } \ |
| 3853 | while (0); |
| 3854 | |
| 3855 | DEF_STUBS |
| 3856 | #undef DEF_STUB |
| 3857 | } |
| 3858 | |
| 3859 | // Stub_table methods. |
| 3860 | |
| 3861 | // Removel all Cortex-A8 stub. |
| 3862 | |
| 3863 | template<bool big_endian> |
| 3864 | void |
| 3865 | Stub_table<big_endian>::remove_all_cortex_a8_stubs() |
| 3866 | { |
| 3867 | for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin(); |
| 3868 | p != this->cortex_a8_stubs_.end(); |
| 3869 | ++p) |
| 3870 | delete p->second; |
| 3871 | this->cortex_a8_stubs_.clear(); |
| 3872 | } |
| 3873 | |
| 3874 | // Relocate one stub. This is a helper for Stub_table::relocate_stubs(). |
| 3875 | |
| 3876 | template<bool big_endian> |
| 3877 | void |
| 3878 | Stub_table<big_endian>::relocate_stub( |
| 3879 | Stub* stub, |
| 3880 | const Relocate_info<32, big_endian>* relinfo, |
| 3881 | Target_arm<big_endian>* arm_target, |
| 3882 | Output_section* output_section, |
| 3883 | unsigned char* view, |
| 3884 | Arm_address address, |
| 3885 | section_size_type view_size) |
| 3886 | { |
| 3887 | const Stub_template* stub_template = stub->stub_template(); |
| 3888 | if (stub_template->reloc_count() != 0) |
| 3889 | { |
| 3890 | // Adjust view to cover the stub only. |
| 3891 | section_size_type offset = stub->offset(); |
| 3892 | section_size_type stub_size = stub_template->size(); |
| 3893 | gold_assert(offset + stub_size <= view_size); |
| 3894 | |
| 3895 | arm_target->relocate_stub(stub, relinfo, output_section, view + offset, |
| 3896 | address + offset, stub_size); |
| 3897 | } |
| 3898 | } |
| 3899 | |
| 3900 | // Relocate all stubs in this stub table. |
| 3901 | |
| 3902 | template<bool big_endian> |
| 3903 | void |
| 3904 | Stub_table<big_endian>::relocate_stubs( |
| 3905 | const Relocate_info<32, big_endian>* relinfo, |
| 3906 | Target_arm<big_endian>* arm_target, |
| 3907 | Output_section* output_section, |
| 3908 | unsigned char* view, |
| 3909 | Arm_address address, |
| 3910 | section_size_type view_size) |
| 3911 | { |
| 3912 | // If we are passed a view bigger than the stub table's. we need to |
| 3913 | // adjust the view. |
| 3914 | gold_assert(address == this->address() |
| 3915 | && (view_size |
| 3916 | == static_cast<section_size_type>(this->data_size()))); |
| 3917 | |
| 3918 | // Relocate all relocation stubs. |
| 3919 | for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin(); |
| 3920 | p != this->reloc_stubs_.end(); |
| 3921 | ++p) |
| 3922 | this->relocate_stub(p->second, relinfo, arm_target, output_section, view, |
| 3923 | address, view_size); |
| 3924 | |
| 3925 | // Relocate all Cortex-A8 stubs. |
| 3926 | for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin(); |
| 3927 | p != this->cortex_a8_stubs_.end(); |
| 3928 | ++p) |
| 3929 | this->relocate_stub(p->second, relinfo, arm_target, output_section, view, |
| 3930 | address, view_size); |
| 3931 | |
| 3932 | // Relocate all ARM V4BX stubs. |
| 3933 | for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin(); |
| 3934 | p != this->arm_v4bx_stubs_.end(); |
| 3935 | ++p) |
| 3936 | { |
| 3937 | if (*p != NULL) |
| 3938 | this->relocate_stub(*p, relinfo, arm_target, output_section, view, |
| 3939 | address, view_size); |
| 3940 | } |
| 3941 | } |
| 3942 | |
| 3943 | // Write out the stubs to file. |
| 3944 | |
| 3945 | template<bool big_endian> |
| 3946 | void |
| 3947 | Stub_table<big_endian>::do_write(Output_file* of) |
| 3948 | { |
| 3949 | off_t offset = this->offset(); |
| 3950 | const section_size_type oview_size = |
| 3951 | convert_to_section_size_type(this->data_size()); |
| 3952 | unsigned char* const oview = of->get_output_view(offset, oview_size); |
| 3953 | |
| 3954 | // Write relocation stubs. |
| 3955 | for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin(); |
| 3956 | p != this->reloc_stubs_.end(); |
| 3957 | ++p) |
| 3958 | { |
| 3959 | Reloc_stub* stub = p->second; |
| 3960 | Arm_address address = this->address() + stub->offset(); |
| 3961 | gold_assert(address |
| 3962 | == align_address(address, |
| 3963 | stub->stub_template()->alignment())); |
| 3964 | stub->write(oview + stub->offset(), stub->stub_template()->size(), |
| 3965 | big_endian); |
| 3966 | } |
| 3967 | |
| 3968 | // Write Cortex-A8 stubs. |
| 3969 | for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin(); |
| 3970 | p != this->cortex_a8_stubs_.end(); |
| 3971 | ++p) |
| 3972 | { |
| 3973 | Cortex_a8_stub* stub = p->second; |
| 3974 | Arm_address address = this->address() + stub->offset(); |
| 3975 | gold_assert(address |
| 3976 | == align_address(address, |
| 3977 | stub->stub_template()->alignment())); |
| 3978 | stub->write(oview + stub->offset(), stub->stub_template()->size(), |
| 3979 | big_endian); |
| 3980 | } |
| 3981 | |
| 3982 | // Write ARM V4BX relocation stubs. |
| 3983 | for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin(); |
| 3984 | p != this->arm_v4bx_stubs_.end(); |
| 3985 | ++p) |
| 3986 | { |
| 3987 | if (*p == NULL) |
| 3988 | continue; |
| 3989 | |
| 3990 | Arm_address address = this->address() + (*p)->offset(); |
| 3991 | gold_assert(address |
| 3992 | == align_address(address, |
| 3993 | (*p)->stub_template()->alignment())); |
| 3994 | (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(), |
| 3995 | big_endian); |
| 3996 | } |
| 3997 | |
| 3998 | of->write_output_view(this->offset(), oview_size, oview); |
| 3999 | } |
| 4000 | |
| 4001 | // Update the data size and address alignment of the stub table at the end |
| 4002 | // of a relaxation pass. Return true if either the data size or the |
| 4003 | // alignment changed in this relaxation pass. |
| 4004 | |
| 4005 | template<bool big_endian> |
| 4006 | bool |
| 4007 | Stub_table<big_endian>::update_data_size_and_addralign() |
| 4008 | { |
| 4009 | off_t size = 0; |
| 4010 | unsigned addralign = 1; |
| 4011 | |
| 4012 | // Go over all stubs in table to compute data size and address alignment. |
| 4013 | |
| 4014 | for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin(); |
| 4015 | p != this->reloc_stubs_.end(); |
| 4016 | ++p) |
| 4017 | { |
| 4018 | const Stub_template* stub_template = p->second->stub_template(); |
| 4019 | addralign = std::max(addralign, stub_template->alignment()); |
| 4020 | size = (align_address(size, stub_template->alignment()) |
| 4021 | + stub_template->size()); |
| 4022 | } |
| 4023 | |
| 4024 | for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin(); |
| 4025 | p != this->cortex_a8_stubs_.end(); |
| 4026 | ++p) |
| 4027 | { |
| 4028 | const Stub_template* stub_template = p->second->stub_template(); |
| 4029 | addralign = std::max(addralign, stub_template->alignment()); |
| 4030 | size = (align_address(size, stub_template->alignment()) |
| 4031 | + stub_template->size()); |
| 4032 | } |
| 4033 | |
| 4034 | for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin(); |
| 4035 | p != this->arm_v4bx_stubs_.end(); |
| 4036 | ++p) |
| 4037 | { |
| 4038 | if (*p == NULL) |
| 4039 | continue; |
| 4040 | |
| 4041 | const Stub_template* stub_template = (*p)->stub_template(); |
| 4042 | addralign = std::max(addralign, stub_template->alignment()); |
| 4043 | size = (align_address(size, stub_template->alignment()) |
| 4044 | + stub_template->size()); |
| 4045 | } |
| 4046 | |
| 4047 | // Check if either data size or alignment changed in this pass. |
| 4048 | // Update prev_data_size_ and prev_addralign_. These will be used |
| 4049 | // as the current data size and address alignment for the next pass. |
| 4050 | bool changed = size != this->prev_data_size_; |
| 4051 | this->prev_data_size_ = size; |
| 4052 | |
| 4053 | if (addralign != this->prev_addralign_) |
| 4054 | changed = true; |
| 4055 | this->prev_addralign_ = addralign; |
| 4056 | |
| 4057 | return changed; |
| 4058 | } |
| 4059 | |
| 4060 | // Finalize the stubs. This sets the offsets of the stubs within the stub |
| 4061 | // table. It also marks all input sections needing Cortex-A8 workaround. |
| 4062 | |
| 4063 | template<bool big_endian> |
| 4064 | void |
| 4065 | Stub_table<big_endian>::finalize_stubs() |
| 4066 | { |
| 4067 | off_t off = 0; |
| 4068 | for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin(); |
| 4069 | p != this->reloc_stubs_.end(); |
| 4070 | ++p) |
| 4071 | { |
| 4072 | Reloc_stub* stub = p->second; |
| 4073 | const Stub_template* stub_template = stub->stub_template(); |
| 4074 | uint64_t stub_addralign = stub_template->alignment(); |
| 4075 | off = align_address(off, stub_addralign); |
| 4076 | stub->set_offset(off); |
| 4077 | off += stub_template->size(); |
| 4078 | } |
| 4079 | |
| 4080 | for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin(); |
| 4081 | p != this->cortex_a8_stubs_.end(); |
| 4082 | ++p) |
| 4083 | { |
| 4084 | Cortex_a8_stub* stub = p->second; |
| 4085 | const Stub_template* stub_template = stub->stub_template(); |
| 4086 | uint64_t stub_addralign = stub_template->alignment(); |
| 4087 | off = align_address(off, stub_addralign); |
| 4088 | stub->set_offset(off); |
| 4089 | off += stub_template->size(); |
| 4090 | |
| 4091 | // Mark input section so that we can determine later if a code section |
| 4092 | // needs the Cortex-A8 workaround quickly. |
| 4093 | Arm_relobj<big_endian>* arm_relobj = |
| 4094 | Arm_relobj<big_endian>::as_arm_relobj(stub->relobj()); |
| 4095 | arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx()); |
| 4096 | } |
| 4097 | |
| 4098 | for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin(); |
| 4099 | p != this->arm_v4bx_stubs_.end(); |
| 4100 | ++p) |
| 4101 | { |
| 4102 | if (*p == NULL) |
| 4103 | continue; |
| 4104 | |
| 4105 | const Stub_template* stub_template = (*p)->stub_template(); |
| 4106 | uint64_t stub_addralign = stub_template->alignment(); |
| 4107 | off = align_address(off, stub_addralign); |
| 4108 | (*p)->set_offset(off); |
| 4109 | off += stub_template->size(); |
| 4110 | } |
| 4111 | |
| 4112 | gold_assert(off <= this->prev_data_size_); |
| 4113 | } |
| 4114 | |
| 4115 | // Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS |
| 4116 | // and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address |
| 4117 | // of the address range seen by the linker. |
| 4118 | |
| 4119 | template<bool big_endian> |
| 4120 | void |
| 4121 | Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range( |
| 4122 | Target_arm<big_endian>* arm_target, |
| 4123 | unsigned char* view, |
| 4124 | Arm_address view_address, |
| 4125 | section_size_type view_size) |
| 4126 | { |
| 4127 | // Cortex-A8 stubs are sorted by addresses of branches being fixed up. |
| 4128 | for (Cortex_a8_stub_list::const_iterator p = |
| 4129 | this->cortex_a8_stubs_.lower_bound(view_address); |
| 4130 | ((p != this->cortex_a8_stubs_.end()) |
| 4131 | && (p->first < (view_address + view_size))); |
| 4132 | ++p) |
| 4133 | { |
| 4134 | // We do not store the THUMB bit in the LSB of either the branch address |
| 4135 | // or the stub offset. There is no need to strip the LSB. |
| 4136 | Arm_address branch_address = p->first; |
| 4137 | const Cortex_a8_stub* stub = p->second; |
| 4138 | Arm_address stub_address = this->address() + stub->offset(); |
| 4139 | |
| 4140 | // Offset of the branch instruction relative to this view. |
| 4141 | section_size_type offset = |
| 4142 | convert_to_section_size_type(branch_address - view_address); |
| 4143 | gold_assert((offset + 4) <= view_size); |
| 4144 | |
| 4145 | arm_target->apply_cortex_a8_workaround(stub, stub_address, |
| 4146 | view + offset, branch_address); |
| 4147 | } |
| 4148 | } |
| 4149 | |
| 4150 | // Arm_input_section methods. |
| 4151 | |
| 4152 | // Initialize an Arm_input_section. |
| 4153 | |
| 4154 | template<bool big_endian> |
| 4155 | void |
| 4156 | Arm_input_section<big_endian>::init() |
| 4157 | { |
| 4158 | Relobj* relobj = this->relobj(); |
| 4159 | unsigned int shndx = this->shndx(); |
| 4160 | |
| 4161 | // Cache these to speed up size and alignment queries. It is too slow |
| 4162 | // to call section_addraglin and section_size every time. |
| 4163 | this->original_addralign_ = relobj->section_addralign(shndx); |
| 4164 | this->original_size_ = relobj->section_size(shndx); |
| 4165 | |
| 4166 | // We want to make this look like the original input section after |
| 4167 | // output sections are finalized. |
| 4168 | Output_section* os = relobj->output_section(shndx); |
| 4169 | off_t offset = relobj->output_section_offset(shndx); |
| 4170 | gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx)); |
| 4171 | this->set_address(os->address() + offset); |
| 4172 | this->set_file_offset(os->offset() + offset); |
| 4173 | |
| 4174 | this->set_current_data_size(this->original_size_); |
| 4175 | this->finalize_data_size(); |
| 4176 | } |
| 4177 | |
| 4178 | template<bool big_endian> |
| 4179 | void |
| 4180 | Arm_input_section<big_endian>::do_write(Output_file* of) |
| 4181 | { |
| 4182 | // We have to write out the original section content. |
| 4183 | section_size_type section_size; |
| 4184 | const unsigned char* section_contents = |
| 4185 | this->relobj()->section_contents(this->shndx(), §ion_size, false); |
| 4186 | of->write(this->offset(), section_contents, section_size); |
| 4187 | |
| 4188 | // If this owns a stub table and it is not empty, write it. |
| 4189 | if (this->is_stub_table_owner() && !this->stub_table_->empty()) |
| 4190 | this->stub_table_->write(of); |
| 4191 | } |
| 4192 | |
| 4193 | // Finalize data size. |
| 4194 | |
| 4195 | template<bool big_endian> |
| 4196 | void |
| 4197 | Arm_input_section<big_endian>::set_final_data_size() |
| 4198 | { |
| 4199 | // If this owns a stub table, finalize its data size as well. |
| 4200 | if (this->is_stub_table_owner()) |
| 4201 | { |
| 4202 | uint64_t address = this->address(); |
| 4203 | |
| 4204 | // The stub table comes after the original section contents. |
| 4205 | address += this->original_size_; |
| 4206 | address = align_address(address, this->stub_table_->addralign()); |
| 4207 | off_t offset = this->offset() + (address - this->address()); |
| 4208 | this->stub_table_->set_address_and_file_offset(address, offset); |
| 4209 | address += this->stub_table_->data_size(); |
| 4210 | gold_assert(address == this->address() + this->current_data_size()); |
| 4211 | } |
| 4212 | |
| 4213 | this->set_data_size(this->current_data_size()); |
| 4214 | } |
| 4215 | |
| 4216 | // Reset address and file offset. |
| 4217 | |
| 4218 | template<bool big_endian> |
| 4219 | void |
| 4220 | Arm_input_section<big_endian>::do_reset_address_and_file_offset() |
| 4221 | { |
| 4222 | // Size of the original input section contents. |
| 4223 | off_t off = convert_types<off_t, uint64_t>(this->original_size_); |
| 4224 | |
| 4225 | // If this is a stub table owner, account for the stub table size. |
| 4226 | if (this->is_stub_table_owner()) |
| 4227 | { |
| 4228 | Stub_table<big_endian>* stub_table = this->stub_table_; |
| 4229 | |
| 4230 | // Reset the stub table's address and file offset. The |
| 4231 | // current data size for child will be updated after that. |
| 4232 | stub_table_->reset_address_and_file_offset(); |
| 4233 | off = align_address(off, stub_table_->addralign()); |
| 4234 | off += stub_table->current_data_size(); |
| 4235 | } |
| 4236 | |
| 4237 | this->set_current_data_size(off); |
| 4238 | } |
| 4239 | |
| 4240 | // Arm_output_section methods. |
| 4241 | |
| 4242 | // Create a stub group for input sections from BEGIN to END. OWNER |
| 4243 | // points to the input section to be the owner a new stub table. |
| 4244 | |
| 4245 | template<bool big_endian> |
| 4246 | void |
| 4247 | Arm_output_section<big_endian>::create_stub_group( |
| 4248 | Input_section_list::const_iterator begin, |
| 4249 | Input_section_list::const_iterator end, |
| 4250 | Input_section_list::const_iterator owner, |
| 4251 | Target_arm<big_endian>* target, |
| 4252 | std::vector<Output_relaxed_input_section*>* new_relaxed_sections) |
| 4253 | { |
| 4254 | // Currently we convert ordinary input sections into relaxed sections only |
| 4255 | // at this point but we may want to support creating relaxed input section |
| 4256 | // very early. So we check here to see if owner is already a relaxed |
| 4257 | // section. |
| 4258 | |
| 4259 | Arm_input_section<big_endian>* arm_input_section; |
| 4260 | if (owner->is_relaxed_input_section()) |
| 4261 | { |
| 4262 | arm_input_section = |
| 4263 | Arm_input_section<big_endian>::as_arm_input_section( |
| 4264 | owner->relaxed_input_section()); |
| 4265 | } |
| 4266 | else |
| 4267 | { |
| 4268 | gold_assert(owner->is_input_section()); |
| 4269 | // Create a new relaxed input section. |
| 4270 | arm_input_section = |
| 4271 | target->new_arm_input_section(owner->relobj(), owner->shndx()); |
| 4272 | new_relaxed_sections->push_back(arm_input_section); |
| 4273 | } |
| 4274 | |
| 4275 | // Create a stub table. |
| 4276 | Stub_table<big_endian>* stub_table = |
| 4277 | target->new_stub_table(arm_input_section); |
| 4278 | |
| 4279 | arm_input_section->set_stub_table(stub_table); |
| 4280 | |
| 4281 | Input_section_list::const_iterator p = begin; |
| 4282 | Input_section_list::const_iterator prev_p; |
| 4283 | |
| 4284 | // Look for input sections or relaxed input sections in [begin ... end]. |
| 4285 | do |
| 4286 | { |
| 4287 | if (p->is_input_section() || p->is_relaxed_input_section()) |
| 4288 | { |
| 4289 | // The stub table information for input sections live |
| 4290 | // in their objects. |
| 4291 | Arm_relobj<big_endian>* arm_relobj = |
| 4292 | Arm_relobj<big_endian>::as_arm_relobj(p->relobj()); |
| 4293 | arm_relobj->set_stub_table(p->shndx(), stub_table); |
| 4294 | } |
| 4295 | prev_p = p++; |
| 4296 | } |
| 4297 | while (prev_p != end); |
| 4298 | } |
| 4299 | |
| 4300 | // Group input sections for stub generation. GROUP_SIZE is roughly the limit |
| 4301 | // of stub groups. We grow a stub group by adding input section until the |
| 4302 | // size is just below GROUP_SIZE. The last input section will be converted |
| 4303 | // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add |
| 4304 | // input section after the stub table, effectively double the group size. |
| 4305 | // |
| 4306 | // This is similar to the group_sections() function in elf32-arm.c but is |
| 4307 | // implemented differently. |
| 4308 | |
| 4309 | template<bool big_endian> |
| 4310 | void |
| 4311 | Arm_output_section<big_endian>::group_sections( |
| 4312 | section_size_type group_size, |
| 4313 | bool stubs_always_after_branch, |
| 4314 | Target_arm<big_endian>* target) |
| 4315 | { |
| 4316 | // We only care about sections containing code. |
| 4317 | if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0) |
| 4318 | return; |
| 4319 | |
| 4320 | // States for grouping. |
| 4321 | typedef enum |
| 4322 | { |
| 4323 | // No group is being built. |
| 4324 | NO_GROUP, |
| 4325 | // A group is being built but the stub table is not found yet. |
| 4326 | // We keep group a stub group until the size is just under GROUP_SIZE. |
| 4327 | // The last input section in the group will be used as the stub table. |
| 4328 | FINDING_STUB_SECTION, |
| 4329 | // A group is being built and we have already found a stub table. |
| 4330 | // We enter this state to grow a stub group by adding input section |
| 4331 | // after the stub table. This effectively doubles the group size. |
| 4332 | HAS_STUB_SECTION |
| 4333 | } State; |
| 4334 | |
| 4335 | // Any newly created relaxed sections are stored here. |
| 4336 | std::vector<Output_relaxed_input_section*> new_relaxed_sections; |
| 4337 | |
| 4338 | State state = NO_GROUP; |
| 4339 | section_size_type off = 0; |
| 4340 | section_size_type group_begin_offset = 0; |
| 4341 | section_size_type group_end_offset = 0; |
| 4342 | section_size_type stub_table_end_offset = 0; |
| 4343 | Input_section_list::const_iterator group_begin = |
| 4344 | this->input_sections().end(); |
| 4345 | Input_section_list::const_iterator stub_table = |
| 4346 | this->input_sections().end(); |
| 4347 | Input_section_list::const_iterator group_end = this->input_sections().end(); |
| 4348 | for (Input_section_list::const_iterator p = this->input_sections().begin(); |
| 4349 | p != this->input_sections().end(); |
| 4350 | ++p) |
| 4351 | { |
| 4352 | section_size_type section_begin_offset = |
| 4353 | align_address(off, p->addralign()); |
| 4354 | section_size_type section_end_offset = |
| 4355 | section_begin_offset + p->data_size(); |
| 4356 | |
| 4357 | // Check to see if we should group the previously seens sections. |
| 4358 | switch (state) |
| 4359 | { |
| 4360 | case NO_GROUP: |
| 4361 | break; |
| 4362 | |
| 4363 | case FINDING_STUB_SECTION: |
| 4364 | // Adding this section makes the group larger than GROUP_SIZE. |
| 4365 | if (section_end_offset - group_begin_offset >= group_size) |
| 4366 | { |
| 4367 | if (stubs_always_after_branch) |
| 4368 | { |
| 4369 | gold_assert(group_end != this->input_sections().end()); |
| 4370 | this->create_stub_group(group_begin, group_end, group_end, |
| 4371 | target, &new_relaxed_sections); |
| 4372 | state = NO_GROUP; |
| 4373 | } |
| 4374 | else |
| 4375 | { |
| 4376 | // But wait, there's more! Input sections up to |
| 4377 | // stub_group_size bytes after the stub table can be |
| 4378 | // handled by it too. |
| 4379 | state = HAS_STUB_SECTION; |
| 4380 | stub_table = group_end; |
| 4381 | stub_table_end_offset = group_end_offset; |
| 4382 | } |
| 4383 | } |
| 4384 | break; |
| 4385 | |
| 4386 | case HAS_STUB_SECTION: |
| 4387 | // Adding this section makes the post stub-section group larger |
| 4388 | // than GROUP_SIZE. |
| 4389 | if (section_end_offset - stub_table_end_offset >= group_size) |
| 4390 | { |
| 4391 | gold_assert(group_end != this->input_sections().end()); |
| 4392 | this->create_stub_group(group_begin, group_end, stub_table, |
| 4393 | target, &new_relaxed_sections); |
| 4394 | state = NO_GROUP; |
| 4395 | } |
| 4396 | break; |
| 4397 | |
| 4398 | default: |
| 4399 | gold_unreachable(); |
| 4400 | } |
| 4401 | |
| 4402 | // If we see an input section and currently there is no group, start |
| 4403 | // a new one. Skip any empty sections. |
| 4404 | if ((p->is_input_section() || p->is_relaxed_input_section()) |
| 4405 | && (p->relobj()->section_size(p->shndx()) != 0)) |
| 4406 | { |
| 4407 | if (state == NO_GROUP) |
| 4408 | { |
| 4409 | state = FINDING_STUB_SECTION; |
| 4410 | group_begin = p; |
| 4411 | group_begin_offset = section_begin_offset; |
| 4412 | } |
| 4413 | |
| 4414 | // Keep track of the last input section seen. |
| 4415 | group_end = p; |
| 4416 | group_end_offset = section_end_offset; |
| 4417 | } |
| 4418 | |
| 4419 | off = section_end_offset; |
| 4420 | } |
| 4421 | |
| 4422 | // Create a stub group for any ungrouped sections. |
| 4423 | if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION) |
| 4424 | { |
| 4425 | gold_assert(group_end != this->input_sections().end()); |
| 4426 | this->create_stub_group(group_begin, group_end, |
| 4427 | (state == FINDING_STUB_SECTION |
| 4428 | ? group_end |
| 4429 | : stub_table), |
| 4430 | target, &new_relaxed_sections); |
| 4431 | } |
| 4432 | |
| 4433 | // Convert input section into relaxed input section in a batch. |
| 4434 | if (!new_relaxed_sections.empty()) |
| 4435 | this->convert_input_sections_to_relaxed_sections(new_relaxed_sections); |
| 4436 | |
| 4437 | // Update the section offsets |
| 4438 | for (size_t i = 0; i < new_relaxed_sections.size(); ++i) |
| 4439 | { |
| 4440 | Arm_relobj<big_endian>* arm_relobj = |
| 4441 | Arm_relobj<big_endian>::as_arm_relobj( |
| 4442 | new_relaxed_sections[i]->relobj()); |
| 4443 | unsigned int shndx = new_relaxed_sections[i]->shndx(); |
| 4444 | // Tell Arm_relobj that this input section is converted. |
| 4445 | arm_relobj->convert_input_section_to_relaxed_section(shndx); |
| 4446 | } |
| 4447 | } |
| 4448 | |
| 4449 | // Arm_relobj methods. |
| 4450 | |
| 4451 | // Determine if we want to scan the SHNDX-th section for relocation stubs. |
| 4452 | // This is a helper for Arm_relobj::scan_sections_for_stubs() below. |
| 4453 | |
| 4454 | template<bool big_endian> |
| 4455 | bool |
| 4456 | Arm_relobj<big_endian>::section_needs_reloc_stub_scanning( |
| 4457 | const elfcpp::Shdr<32, big_endian>& shdr, |
| 4458 | const Relobj::Output_sections& out_sections, |
| 4459 | const Symbol_table *symtab) |
| 4460 | { |
| 4461 | unsigned int sh_type = shdr.get_sh_type(); |
| 4462 | if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA) |
| 4463 | return false; |
| 4464 | |
| 4465 | // Ignore empty section. |
| 4466 | off_t sh_size = shdr.get_sh_size(); |
| 4467 | if (sh_size == 0) |
| 4468 | return false; |
| 4469 | |
| 4470 | // Ignore reloc section with bad info. This error will be |
| 4471 | // reported in the final link. |
| 4472 | unsigned int index = this->adjust_shndx(shdr.get_sh_info()); |
| 4473 | if (index >= this->shnum()) |
| 4474 | return false; |
| 4475 | |
| 4476 | // This relocation section is against a section which we |
| 4477 | // discarded or if the section is folded into another |
| 4478 | // section due to ICF. |
| 4479 | if (out_sections[index] == NULL || symtab->is_section_folded(this, index)) |
| 4480 | return false; |
| 4481 | |
| 4482 | // Ignore reloc section with unexpected symbol table. The |
| 4483 | // error will be reported in the final link. |
| 4484 | if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx()) |
| 4485 | return false; |
| 4486 | |
| 4487 | unsigned int reloc_size; |
| 4488 | if (sh_type == elfcpp::SHT_REL) |
| 4489 | reloc_size = elfcpp::Elf_sizes<32>::rel_size; |
| 4490 | else |
| 4491 | reloc_size = elfcpp::Elf_sizes<32>::rela_size; |
| 4492 | |
| 4493 | // Ignore reloc section with unexpected entsize or uneven size. |
| 4494 | // The error will be reported in the final link. |
| 4495 | if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0) |
| 4496 | return false; |
| 4497 | |
| 4498 | return true; |
| 4499 | } |
| 4500 | |
| 4501 | // Determine if we want to scan the SHNDX-th section for non-relocation stubs. |
| 4502 | // This is a helper for Arm_relobj::scan_sections_for_stubs() below. |
| 4503 | |
| 4504 | template<bool big_endian> |
| 4505 | bool |
| 4506 | Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning( |
| 4507 | const elfcpp::Shdr<32, big_endian>& shdr, |
| 4508 | unsigned int shndx, |
| 4509 | Output_section* os, |
| 4510 | const Symbol_table* symtab) |
| 4511 | { |
| 4512 | // We only scan non-empty code sections. |
| 4513 | if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) == 0 |
| 4514 | || shdr.get_sh_size() == 0) |
| 4515 | return false; |
| 4516 | |
| 4517 | // Ignore discarded or ICF'ed sections. |
| 4518 | if (os == NULL || symtab->is_section_folded(this, shndx)) |
| 4519 | return false; |
| 4520 | |
| 4521 | // Find output address of section. |
| 4522 | Arm_address address = os->output_address(this, shndx, 0); |
| 4523 | |
| 4524 | // If the section does not cross any 4K-boundaries, it does not need to |
| 4525 | // be scanned. |
| 4526 | if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU)) |
| 4527 | return false; |
| 4528 | |
| 4529 | return true; |
| 4530 | } |
| 4531 | |
| 4532 | // Scan a section for Cortex-A8 workaround. |
| 4533 | |
| 4534 | template<bool big_endian> |
| 4535 | void |
| 4536 | Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum( |
| 4537 | const elfcpp::Shdr<32, big_endian>& shdr, |
| 4538 | unsigned int shndx, |
| 4539 | Output_section* os, |
| 4540 | Target_arm<big_endian>* arm_target) |
| 4541 | { |
| 4542 | Arm_address output_address = os->output_address(this, shndx, 0); |
| 4543 | |
| 4544 | // Get the section contents. |
| 4545 | section_size_type input_view_size = 0; |
| 4546 | const unsigned char* input_view = |
| 4547 | this->section_contents(shndx, &input_view_size, false); |
| 4548 | |
| 4549 | // We need to go through the mapping symbols to determine what to |
| 4550 | // scan. There are two reasons. First, we should look at THUMB code and |
| 4551 | // THUMB code only. Second, we only want to look at the 4K-page boundary |
| 4552 | // to speed up the scanning. |
| 4553 | |
| 4554 | // Look for the first mapping symbol in this section. It should be |
| 4555 | // at (shndx, 0). |
| 4556 | Mapping_symbol_position section_start(shndx, 0); |
| 4557 | typename Mapping_symbols_info::const_iterator p = |
| 4558 | this->mapping_symbols_info_.lower_bound(section_start); |
| 4559 | |
| 4560 | if (p == this->mapping_symbols_info_.end() |
| 4561 | || p->first != section_start) |
| 4562 | { |
| 4563 | gold_warning(_("Cortex-A8 erratum scanning failed because there " |
| 4564 | "is no mapping symbols for section %u of %s"), |
| 4565 | shndx, this->name().c_str()); |
| 4566 | return; |
| 4567 | } |
| 4568 | |
| 4569 | while (p != this->mapping_symbols_info_.end() |
| 4570 | && p->first.first == shndx) |
| 4571 | { |
| 4572 | typename Mapping_symbols_info::const_iterator next = |
| 4573 | this->mapping_symbols_info_.upper_bound(p->first); |
| 4574 | |
| 4575 | // Only scan part of a section with THUMB code. |
| 4576 | if (p->second == 't') |
| 4577 | { |
| 4578 | // Determine the end of this range. |
| 4579 | section_size_type span_start = |
| 4580 | convert_to_section_size_type(p->first.second); |
| 4581 | section_size_type span_end; |
| 4582 | if (next != this->mapping_symbols_info_.end() |
| 4583 | && next->first.first == shndx) |
| 4584 | span_end = convert_to_section_size_type(next->first.second); |
| 4585 | else |
| 4586 | span_end = convert_to_section_size_type(shdr.get_sh_size()); |
| 4587 | |
| 4588 | if (((span_start + output_address) & ~0xfffUL) |
| 4589 | != ((span_end + output_address - 1) & ~0xfffUL)) |
| 4590 | { |
| 4591 | arm_target->scan_span_for_cortex_a8_erratum(this, shndx, |
| 4592 | span_start, span_end, |
| 4593 | input_view, |
| 4594 | output_address); |
| 4595 | } |
| 4596 | } |
| 4597 | |
| 4598 | p = next; |
| 4599 | } |
| 4600 | } |
| 4601 | |
| 4602 | // Scan relocations for stub generation. |
| 4603 | |
| 4604 | template<bool big_endian> |
| 4605 | void |
| 4606 | Arm_relobj<big_endian>::scan_sections_for_stubs( |
| 4607 | Target_arm<big_endian>* arm_target, |
| 4608 | const Symbol_table* symtab, |
| 4609 | const Layout* layout) |
| 4610 | { |
| 4611 | unsigned int shnum = this->shnum(); |
| 4612 | const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size; |
| 4613 | |
| 4614 | // Read the section headers. |
| 4615 | const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(), |
| 4616 | shnum * shdr_size, |
| 4617 | true, true); |
| 4618 | |
| 4619 | // To speed up processing, we set up hash tables for fast lookup of |
| 4620 | // input offsets to output addresses. |
| 4621 | this->initialize_input_to_output_maps(); |
| 4622 | |
| 4623 | const Relobj::Output_sections& out_sections(this->output_sections()); |
| 4624 | |
| 4625 | Relocate_info<32, big_endian> relinfo; |
| 4626 | relinfo.symtab = symtab; |
| 4627 | relinfo.layout = layout; |
| 4628 | relinfo.object = this; |
| 4629 | |
| 4630 | // Do relocation stubs scanning. |
| 4631 | const unsigned char* p = pshdrs + shdr_size; |
| 4632 | for (unsigned int i = 1; i < shnum; ++i, p += shdr_size) |
| 4633 | { |
| 4634 | const elfcpp::Shdr<32, big_endian> shdr(p); |
| 4635 | if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab)) |
| 4636 | { |
| 4637 | unsigned int index = this->adjust_shndx(shdr.get_sh_info()); |
| 4638 | Arm_address output_offset = this->get_output_section_offset(index); |
| 4639 | Arm_address output_address; |
| 4640 | if(output_offset != invalid_address) |
| 4641 | output_address = out_sections[index]->address() + output_offset; |
| 4642 | else |
| 4643 | { |
| 4644 | // Currently this only happens for a relaxed section. |
| 4645 | const Output_relaxed_input_section* poris = |
| 4646 | out_sections[index]->find_relaxed_input_section(this, index); |
| 4647 | gold_assert(poris != NULL); |
| 4648 | output_address = poris->address(); |
| 4649 | } |
| 4650 | |
| 4651 | // Get the relocations. |
| 4652 | const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(), |
| 4653 | shdr.get_sh_size(), |
| 4654 | true, false); |
| 4655 | |
| 4656 | // Get the section contents. This does work for the case in which |
| 4657 | // we modify the contents of an input section. We need to pass the |
| 4658 | // output view under such circumstances. |
| 4659 | section_size_type input_view_size = 0; |
| 4660 | const unsigned char* input_view = |
| 4661 | this->section_contents(index, &input_view_size, false); |
| 4662 | |
| 4663 | relinfo.reloc_shndx = i; |
| 4664 | relinfo.data_shndx = index; |
| 4665 | unsigned int sh_type = shdr.get_sh_type(); |
| 4666 | unsigned int reloc_size; |
| 4667 | if (sh_type == elfcpp::SHT_REL) |
| 4668 | reloc_size = elfcpp::Elf_sizes<32>::rel_size; |
| 4669 | else |
| 4670 | reloc_size = elfcpp::Elf_sizes<32>::rela_size; |
| 4671 | |
| 4672 | Output_section* os = out_sections[index]; |
| 4673 | arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs, |
| 4674 | shdr.get_sh_size() / reloc_size, |
| 4675 | os, |
| 4676 | output_offset == invalid_address, |
| 4677 | input_view, output_address, |
| 4678 | input_view_size); |
| 4679 | } |
| 4680 | } |
| 4681 | |
| 4682 | // Do Cortex-A8 erratum stubs scanning. This has to be done for a section |
| 4683 | // after its relocation section, if there is one, is processed for |
| 4684 | // relocation stubs. Merging this loop with the one above would have been |
| 4685 | // complicated since we would have had to make sure that relocation stub |
| 4686 | // scanning is done first. |
| 4687 | if (arm_target->fix_cortex_a8()) |
| 4688 | { |
| 4689 | const unsigned char* p = pshdrs + shdr_size; |
| 4690 | for (unsigned int i = 1; i < shnum; ++i, p += shdr_size) |
| 4691 | { |
| 4692 | const elfcpp::Shdr<32, big_endian> shdr(p); |
| 4693 | if (this->section_needs_cortex_a8_stub_scanning(shdr, i, |
| 4694 | out_sections[i], |
| 4695 | symtab)) |
| 4696 | this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i], |
| 4697 | arm_target); |
| 4698 | } |
| 4699 | } |
| 4700 | |
| 4701 | // After we've done the relocations, we release the hash tables, |
| 4702 | // since we no longer need them. |
| 4703 | this->free_input_to_output_maps(); |
| 4704 | } |
| 4705 | |
| 4706 | // Count the local symbols. The ARM backend needs to know if a symbol |
| 4707 | // is a THUMB function or not. For global symbols, it is easy because |
| 4708 | // the Symbol object keeps the ELF symbol type. For local symbol it is |
| 4709 | // harder because we cannot access this information. So we override the |
| 4710 | // do_count_local_symbol in parent and scan local symbols to mark |
| 4711 | // THUMB functions. This is not the most efficient way but I do not want to |
| 4712 | // slow down other ports by calling a per symbol targer hook inside |
| 4713 | // Sized_relobj<size, big_endian>::do_count_local_symbols. |
| 4714 | |
| 4715 | template<bool big_endian> |
| 4716 | void |
| 4717 | Arm_relobj<big_endian>::do_count_local_symbols( |
| 4718 | Stringpool_template<char>* pool, |
| 4719 | Stringpool_template<char>* dynpool) |
| 4720 | { |
| 4721 | // We need to fix-up the values of any local symbols whose type are |
| 4722 | // STT_ARM_TFUNC. |
| 4723 | |
| 4724 | // Ask parent to count the local symbols. |
| 4725 | Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool); |
| 4726 | const unsigned int loccount = this->local_symbol_count(); |
| 4727 | if (loccount == 0) |
| 4728 | return; |
| 4729 | |
| 4730 | // Intialize the thumb function bit-vector. |
| 4731 | std::vector<bool> empty_vector(loccount, false); |
| 4732 | this->local_symbol_is_thumb_function_.swap(empty_vector); |
| 4733 | |
| 4734 | // Read the symbol table section header. |
| 4735 | const unsigned int symtab_shndx = this->symtab_shndx(); |
| 4736 | elfcpp::Shdr<32, big_endian> |
| 4737 | symtabshdr(this, this->elf_file()->section_header(symtab_shndx)); |
| 4738 | gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); |
| 4739 | |
| 4740 | // Read the local symbols. |
| 4741 | const int sym_size =elfcpp::Elf_sizes<32>::sym_size; |
| 4742 | gold_assert(loccount == symtabshdr.get_sh_info()); |
| 4743 | off_t locsize = loccount * sym_size; |
| 4744 | const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(), |
| 4745 | locsize, true, true); |
| 4746 | |
| 4747 | // For mapping symbol processing, we need to read the symbol names. |
| 4748 | unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link()); |
| 4749 | if (strtab_shndx >= this->shnum()) |
| 4750 | { |
| 4751 | this->error(_("invalid symbol table name index: %u"), strtab_shndx); |
| 4752 | return; |
| 4753 | } |
| 4754 | |
| 4755 | elfcpp::Shdr<32, big_endian> |
| 4756 | strtabshdr(this, this->elf_file()->section_header(strtab_shndx)); |
| 4757 | if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB) |
| 4758 | { |
| 4759 | this->error(_("symbol table name section has wrong type: %u"), |
| 4760 | static_cast<unsigned int>(strtabshdr.get_sh_type())); |
| 4761 | return; |
| 4762 | } |
| 4763 | const char* pnames = |
| 4764 | reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(), |
| 4765 | strtabshdr.get_sh_size(), |
| 4766 | false, false)); |
| 4767 | |
| 4768 | // Loop over the local symbols and mark any local symbols pointing |
| 4769 | // to THUMB functions. |
| 4770 | |
| 4771 | // Skip the first dummy symbol. |
| 4772 | psyms += sym_size; |
| 4773 | typename Sized_relobj<32, big_endian>::Local_values* plocal_values = |
| 4774 | this->local_values(); |
| 4775 | for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size) |
| 4776 | { |
| 4777 | elfcpp::Sym<32, big_endian> sym(psyms); |
| 4778 | elfcpp::STT st_type = sym.get_st_type(); |
| 4779 | Symbol_value<32>& lv((*plocal_values)[i]); |
| 4780 | Arm_address input_value = lv.input_value(); |
| 4781 | |
| 4782 | // Check to see if this is a mapping symbol. |
| 4783 | const char* sym_name = pnames + sym.get_st_name(); |
| 4784 | if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name)) |
| 4785 | { |
| 4786 | unsigned int input_shndx = sym.get_st_shndx(); |
| 4787 | |
| 4788 | // Strip of LSB in case this is a THUMB symbol. |
| 4789 | Mapping_symbol_position msp(input_shndx, input_value & ~1U); |
| 4790 | this->mapping_symbols_info_[msp] = sym_name[1]; |
| 4791 | } |
| 4792 | |
| 4793 | if (st_type == elfcpp::STT_ARM_TFUNC |
| 4794 | || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0))) |
| 4795 | { |
| 4796 | // This is a THUMB function. Mark this and canonicalize the |
| 4797 | // symbol value by setting LSB. |
| 4798 | this->local_symbol_is_thumb_function_[i] = true; |
| 4799 | if ((input_value & 1) == 0) |
| 4800 | lv.set_input_value(input_value | 1); |
| 4801 | } |
| 4802 | } |
| 4803 | } |
| 4804 | |
| 4805 | // Relocate sections. |
| 4806 | template<bool big_endian> |
| 4807 | void |
| 4808 | Arm_relobj<big_endian>::do_relocate_sections( |
| 4809 | const Symbol_table* symtab, |
| 4810 | const Layout* layout, |
| 4811 | const unsigned char* pshdrs, |
| 4812 | typename Sized_relobj<32, big_endian>::Views* pviews) |
| 4813 | { |
| 4814 | // Call parent to relocate sections. |
| 4815 | Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs, |
| 4816 | pviews); |
| 4817 | |
| 4818 | // We do not generate stubs if doing a relocatable link. |
| 4819 | if (parameters->options().relocatable()) |
| 4820 | return; |
| 4821 | |
| 4822 | // Relocate stub tables. |
| 4823 | unsigned int shnum = this->shnum(); |
| 4824 | |
| 4825 | Target_arm<big_endian>* arm_target = |
| 4826 | Target_arm<big_endian>::default_target(); |
| 4827 | |
| 4828 | Relocate_info<32, big_endian> relinfo; |
| 4829 | relinfo.symtab = symtab; |
| 4830 | relinfo.layout = layout; |
| 4831 | relinfo.object = this; |
| 4832 | |
| 4833 | for (unsigned int i = 1; i < shnum; ++i) |
| 4834 | { |
| 4835 | Arm_input_section<big_endian>* arm_input_section = |
| 4836 | arm_target->find_arm_input_section(this, i); |
| 4837 | |
| 4838 | if (arm_input_section != NULL |
| 4839 | && arm_input_section->is_stub_table_owner() |
| 4840 | && !arm_input_section->stub_table()->empty()) |
| 4841 | { |
| 4842 | // We cannot discard a section if it owns a stub table. |
| 4843 | Output_section* os = this->output_section(i); |
| 4844 | gold_assert(os != NULL); |
| 4845 | |
| 4846 | relinfo.reloc_shndx = elfcpp::SHN_UNDEF; |
| 4847 | relinfo.reloc_shdr = NULL; |
| 4848 | relinfo.data_shndx = i; |
| 4849 | relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size; |
| 4850 | |
| 4851 | gold_assert((*pviews)[i].view != NULL); |
| 4852 | |
| 4853 | // We are passed the output section view. Adjust it to cover the |
| 4854 | // stub table only. |
| 4855 | Stub_table<big_endian>* stub_table = arm_input_section->stub_table(); |
| 4856 | gold_assert((stub_table->address() >= (*pviews)[i].address) |
| 4857 | && ((stub_table->address() + stub_table->data_size()) |
| 4858 | <= (*pviews)[i].address + (*pviews)[i].view_size)); |
| 4859 | |
| 4860 | off_t offset = stub_table->address() - (*pviews)[i].address; |
| 4861 | unsigned char* view = (*pviews)[i].view + offset; |
| 4862 | Arm_address address = stub_table->address(); |
| 4863 | section_size_type view_size = stub_table->data_size(); |
| 4864 | |
| 4865 | stub_table->relocate_stubs(&relinfo, arm_target, os, view, address, |
| 4866 | view_size); |
| 4867 | } |
| 4868 | |
| 4869 | // Apply Cortex A8 workaround if applicable. |
| 4870 | if (this->section_has_cortex_a8_workaround(i)) |
| 4871 | { |
| 4872 | unsigned char* view = (*pviews)[i].view; |
| 4873 | Arm_address view_address = (*pviews)[i].address; |
| 4874 | section_size_type view_size = (*pviews)[i].view_size; |
| 4875 | Stub_table<big_endian>* stub_table = this->stub_tables_[i]; |
| 4876 | |
| 4877 | // Adjust view to cover section. |
| 4878 | Output_section* os = this->output_section(i); |
| 4879 | gold_assert(os != NULL); |
| 4880 | Arm_address section_address = os->output_address(this, i, 0); |
| 4881 | uint64_t section_size = this->section_size(i); |
| 4882 | |
| 4883 | gold_assert(section_address >= view_address |
| 4884 | && ((section_address + section_size) |
| 4885 | <= (view_address + view_size))); |
| 4886 | |
| 4887 | unsigned char* section_view = view + (section_address - view_address); |
| 4888 | |
| 4889 | // Apply the Cortex-A8 workaround to the output address range |
| 4890 | // corresponding to this input section. |
| 4891 | stub_table->apply_cortex_a8_workaround_to_address_range( |
| 4892 | arm_target, |
| 4893 | section_view, |
| 4894 | section_address, |
| 4895 | section_size); |
| 4896 | } |
| 4897 | } |
| 4898 | } |
| 4899 | |
| 4900 | // Helper functions for both Arm_relobj and Arm_dynobj to read ARM |
| 4901 | // ABI information. |
| 4902 | |
| 4903 | template<bool big_endian> |
| 4904 | Attributes_section_data* |
| 4905 | read_arm_attributes_section( |
| 4906 | Object* object, |
| 4907 | Read_symbols_data *sd) |
| 4908 | { |
| 4909 | // Read the attributes section if there is one. |
| 4910 | // We read from the end because gas seems to put it near the end of |
| 4911 | // the section headers. |
| 4912 | const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size; |
| 4913 | const unsigned char *ps = |
| 4914 | sd->section_headers->data() + shdr_size * (object->shnum() - 1); |
| 4915 | for (unsigned int i = object->shnum(); i > 0; --i, ps -= shdr_size) |
| 4916 | { |
| 4917 | elfcpp::Shdr<32, big_endian> shdr(ps); |
| 4918 | if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES) |
| 4919 | { |
| 4920 | section_offset_type section_offset = shdr.get_sh_offset(); |
| 4921 | section_size_type section_size = |
| 4922 | convert_to_section_size_type(shdr.get_sh_size()); |
| 4923 | File_view* view = object->get_lasting_view(section_offset, |
| 4924 | section_size, true, false); |
| 4925 | return new Attributes_section_data(view->data(), section_size); |
| 4926 | } |
| 4927 | } |
| 4928 | return NULL; |
| 4929 | } |
| 4930 | |
| 4931 | // Read the symbol information. |
| 4932 | |
| 4933 | template<bool big_endian> |
| 4934 | void |
| 4935 | Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd) |
| 4936 | { |
| 4937 | // Call parent class to read symbol information. |
| 4938 | Sized_relobj<32, big_endian>::do_read_symbols(sd); |
| 4939 | |
| 4940 | // Read processor-specific flags in ELF file header. |
| 4941 | const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset, |
| 4942 | elfcpp::Elf_sizes<32>::ehdr_size, |
| 4943 | true, false); |
| 4944 | elfcpp::Ehdr<32, big_endian> ehdr(pehdr); |
| 4945 | this->processor_specific_flags_ = ehdr.get_e_flags(); |
| 4946 | this->attributes_section_data_ = |
| 4947 | read_arm_attributes_section<big_endian>(this, sd); |
| 4948 | } |
| 4949 | |
| 4950 | // Process relocations for garbage collection. The ARM target uses .ARM.exidx |
| 4951 | // sections for unwinding. These sections are referenced implicitly by |
| 4952 | // text sections linked in the section headers. If we ignore these implict |
| 4953 | // references, the .ARM.exidx sections and any .ARM.extab sections they use |
| 4954 | // will be garbage-collected incorrectly. Hence we override the same function |
| 4955 | // in the base class to handle these implicit references. |
| 4956 | |
| 4957 | template<bool big_endian> |
| 4958 | void |
| 4959 | Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab, |
| 4960 | Layout* layout, |
| 4961 | Read_relocs_data* rd) |
| 4962 | { |
| 4963 | // First, call base class method to process relocations in this object. |
| 4964 | Sized_relobj<32, big_endian>::do_gc_process_relocs(symtab, layout, rd); |
| 4965 | |
| 4966 | unsigned int shnum = this->shnum(); |
| 4967 | const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size; |
| 4968 | const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(), |
| 4969 | shnum * shdr_size, |
| 4970 | true, true); |
| 4971 | |
| 4972 | // Scan section headers for sections of type SHT_ARM_EXIDX. Add references |
| 4973 | // to these from the linked text sections. |
| 4974 | const unsigned char* ps = pshdrs + shdr_size; |
| 4975 | for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size) |
| 4976 | { |
| 4977 | elfcpp::Shdr<32, big_endian> shdr(ps); |
| 4978 | if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX) |
| 4979 | { |
| 4980 | // Found an .ARM.exidx section, add it to the set of reachable |
| 4981 | // sections from its linked text section. |
| 4982 | unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link()); |
| 4983 | symtab->gc()->add_reference(this, text_shndx, this, i); |
| 4984 | } |
| 4985 | } |
| 4986 | } |
| 4987 | |
| 4988 | // Arm_dynobj methods. |
| 4989 | |
| 4990 | // Read the symbol information. |
| 4991 | |
| 4992 | template<bool big_endian> |
| 4993 | void |
| 4994 | Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd) |
| 4995 | { |
| 4996 | // Call parent class to read symbol information. |
| 4997 | Sized_dynobj<32, big_endian>::do_read_symbols(sd); |
| 4998 | |
| 4999 | // Read processor-specific flags in ELF file header. |
| 5000 | const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset, |
| 5001 | elfcpp::Elf_sizes<32>::ehdr_size, |
| 5002 | true, false); |
| 5003 | elfcpp::Ehdr<32, big_endian> ehdr(pehdr); |
| 5004 | this->processor_specific_flags_ = ehdr.get_e_flags(); |
| 5005 | this->attributes_section_data_ = |
| 5006 | read_arm_attributes_section<big_endian>(this, sd); |
| 5007 | } |
| 5008 | |
| 5009 | // Stub_addend_reader methods. |
| 5010 | |
| 5011 | // Read the addend of a REL relocation of type R_TYPE at VIEW. |
| 5012 | |
| 5013 | template<bool big_endian> |
| 5014 | elfcpp::Elf_types<32>::Elf_Swxword |
| 5015 | Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()( |
| 5016 | unsigned int r_type, |
| 5017 | const unsigned char* view, |
| 5018 | const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const |
| 5019 | { |
| 5020 | typedef struct Arm_relocate_functions<big_endian> RelocFuncs; |
| 5021 | |
| 5022 | switch (r_type) |
| 5023 | { |
| 5024 | case elfcpp::R_ARM_CALL: |
| 5025 | case elfcpp::R_ARM_JUMP24: |
| 5026 | case elfcpp::R_ARM_PLT32: |
| 5027 | { |
| 5028 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 5029 | const Valtype* wv = reinterpret_cast<const Valtype*>(view); |
| 5030 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 5031 | return utils::sign_extend<26>(val << 2); |
| 5032 | } |
| 5033 | |
| 5034 | case elfcpp::R_ARM_THM_CALL: |
| 5035 | case elfcpp::R_ARM_THM_JUMP24: |
| 5036 | case elfcpp::R_ARM_THM_XPC22: |
| 5037 | { |
| 5038 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 5039 | const Valtype* wv = reinterpret_cast<const Valtype*>(view); |
| 5040 | Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 5041 | Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 5042 | return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn); |
| 5043 | } |
| 5044 | |
| 5045 | case elfcpp::R_ARM_THM_JUMP19: |
| 5046 | { |
| 5047 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 5048 | const Valtype* wv = reinterpret_cast<const Valtype*>(view); |
| 5049 | Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 5050 | Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 5051 | return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn); |
| 5052 | } |
| 5053 | |
| 5054 | default: |
| 5055 | gold_unreachable(); |
| 5056 | } |
| 5057 | } |
| 5058 | |
| 5059 | // A class to handle the PLT data. |
| 5060 | |
| 5061 | template<bool big_endian> |
| 5062 | class Output_data_plt_arm : public Output_section_data |
| 5063 | { |
| 5064 | public: |
| 5065 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian> |
| 5066 | Reloc_section; |
| 5067 | |
| 5068 | Output_data_plt_arm(Layout*, Output_data_space*); |
| 5069 | |
| 5070 | // Add an entry to the PLT. |
| 5071 | void |
| 5072 | add_entry(Symbol* gsym); |
| 5073 | |
| 5074 | // Return the .rel.plt section data. |
| 5075 | const Reloc_section* |
| 5076 | rel_plt() const |
| 5077 | { return this->rel_; } |
| 5078 | |
| 5079 | protected: |
| 5080 | void |
| 5081 | do_adjust_output_section(Output_section* os); |
| 5082 | |
| 5083 | // Write to a map file. |
| 5084 | void |
| 5085 | do_print_to_mapfile(Mapfile* mapfile) const |
| 5086 | { mapfile->print_output_data(this, _("** PLT")); } |
| 5087 | |
| 5088 | private: |
| 5089 | // Template for the first PLT entry. |
| 5090 | static const uint32_t first_plt_entry[5]; |
| 5091 | |
| 5092 | // Template for subsequent PLT entries. |
| 5093 | static const uint32_t plt_entry[3]; |
| 5094 | |
| 5095 | // Set the final size. |
| 5096 | void |
| 5097 | set_final_data_size() |
| 5098 | { |
| 5099 | this->set_data_size(sizeof(first_plt_entry) |
| 5100 | + this->count_ * sizeof(plt_entry)); |
| 5101 | } |
| 5102 | |
| 5103 | // Write out the PLT data. |
| 5104 | void |
| 5105 | do_write(Output_file*); |
| 5106 | |
| 5107 | // The reloc section. |
| 5108 | Reloc_section* rel_; |
| 5109 | // The .got.plt section. |
| 5110 | Output_data_space* got_plt_; |
| 5111 | // The number of PLT entries. |
| 5112 | unsigned int count_; |
| 5113 | }; |
| 5114 | |
| 5115 | // Create the PLT section. The ordinary .got section is an argument, |
| 5116 | // since we need to refer to the start. We also create our own .got |
| 5117 | // section just for PLT entries. |
| 5118 | |
| 5119 | template<bool big_endian> |
| 5120 | Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout, |
| 5121 | Output_data_space* got_plt) |
| 5122 | : Output_section_data(4), got_plt_(got_plt), count_(0) |
| 5123 | { |
| 5124 | this->rel_ = new Reloc_section(false); |
| 5125 | layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL, |
| 5126 | elfcpp::SHF_ALLOC, this->rel_, true, false, |
| 5127 | false, false); |
| 5128 | } |
| 5129 | |
| 5130 | template<bool big_endian> |
| 5131 | void |
| 5132 | Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os) |
| 5133 | { |
| 5134 | os->set_entsize(0); |
| 5135 | } |
| 5136 | |
| 5137 | // Add an entry to the PLT. |
| 5138 | |
| 5139 | template<bool big_endian> |
| 5140 | void |
| 5141 | Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym) |
| 5142 | { |
| 5143 | gold_assert(!gsym->has_plt_offset()); |
| 5144 | |
| 5145 | // Note that when setting the PLT offset we skip the initial |
| 5146 | // reserved PLT entry. |
| 5147 | gsym->set_plt_offset((this->count_) * sizeof(plt_entry) |
| 5148 | + sizeof(first_plt_entry)); |
| 5149 | |
| 5150 | ++this->count_; |
| 5151 | |
| 5152 | section_offset_type got_offset = this->got_plt_->current_data_size(); |
| 5153 | |
| 5154 | // Every PLT entry needs a GOT entry which points back to the PLT |
| 5155 | // entry (this will be changed by the dynamic linker, normally |
| 5156 | // lazily when the function is called). |
| 5157 | this->got_plt_->set_current_data_size(got_offset + 4); |
| 5158 | |
| 5159 | // Every PLT entry needs a reloc. |
| 5160 | gsym->set_needs_dynsym_entry(); |
| 5161 | this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_, |
| 5162 | got_offset); |
| 5163 | |
| 5164 | // Note that we don't need to save the symbol. The contents of the |
| 5165 | // PLT are independent of which symbols are used. The symbols only |
| 5166 | // appear in the relocations. |
| 5167 | } |
| 5168 | |
| 5169 | // ARM PLTs. |
| 5170 | // FIXME: This is not very flexible. Right now this has only been tested |
| 5171 | // on armv5te. If we are to support additional architecture features like |
| 5172 | // Thumb-2 or BE8, we need to make this more flexible like GNU ld. |
| 5173 | |
| 5174 | // The first entry in the PLT. |
| 5175 | template<bool big_endian> |
| 5176 | const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] = |
| 5177 | { |
| 5178 | 0xe52de004, // str lr, [sp, #-4]! |
| 5179 | 0xe59fe004, // ldr lr, [pc, #4] |
| 5180 | 0xe08fe00e, // add lr, pc, lr |
| 5181 | 0xe5bef008, // ldr pc, [lr, #8]! |
| 5182 | 0x00000000, // &GOT[0] - . |
| 5183 | }; |
| 5184 | |
| 5185 | // Subsequent entries in the PLT. |
| 5186 | |
| 5187 | template<bool big_endian> |
| 5188 | const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] = |
| 5189 | { |
| 5190 | 0xe28fc600, // add ip, pc, #0xNN00000 |
| 5191 | 0xe28cca00, // add ip, ip, #0xNN000 |
| 5192 | 0xe5bcf000, // ldr pc, [ip, #0xNNN]! |
| 5193 | }; |
| 5194 | |
| 5195 | // Write out the PLT. This uses the hand-coded instructions above, |
| 5196 | // and adjusts them as needed. This is all specified by the arm ELF |
| 5197 | // Processor Supplement. |
| 5198 | |
| 5199 | template<bool big_endian> |
| 5200 | void |
| 5201 | Output_data_plt_arm<big_endian>::do_write(Output_file* of) |
| 5202 | { |
| 5203 | const off_t offset = this->offset(); |
| 5204 | const section_size_type oview_size = |
| 5205 | convert_to_section_size_type(this->data_size()); |
| 5206 | unsigned char* const oview = of->get_output_view(offset, oview_size); |
| 5207 | |
| 5208 | const off_t got_file_offset = this->got_plt_->offset(); |
| 5209 | const section_size_type got_size = |
| 5210 | convert_to_section_size_type(this->got_plt_->data_size()); |
| 5211 | unsigned char* const got_view = of->get_output_view(got_file_offset, |
| 5212 | got_size); |
| 5213 | unsigned char* pov = oview; |
| 5214 | |
| 5215 | Arm_address plt_address = this->address(); |
| 5216 | Arm_address got_address = this->got_plt_->address(); |
| 5217 | |
| 5218 | // Write first PLT entry. All but the last word are constants. |
| 5219 | const size_t num_first_plt_words = (sizeof(first_plt_entry) |
| 5220 | / sizeof(plt_entry[0])); |
| 5221 | for (size_t i = 0; i < num_first_plt_words - 1; i++) |
| 5222 | elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]); |
| 5223 | // Last word in first PLT entry is &GOT[0] - . |
| 5224 | elfcpp::Swap<32, big_endian>::writeval(pov + 16, |
| 5225 | got_address - (plt_address + 16)); |
| 5226 | pov += sizeof(first_plt_entry); |
| 5227 | |
| 5228 | unsigned char* got_pov = got_view; |
| 5229 | |
| 5230 | memset(got_pov, 0, 12); |
| 5231 | got_pov += 12; |
| 5232 | |
| 5233 | const int rel_size = elfcpp::Elf_sizes<32>::rel_size; |
| 5234 | unsigned int plt_offset = sizeof(first_plt_entry); |
| 5235 | unsigned int plt_rel_offset = 0; |
| 5236 | unsigned int got_offset = 12; |
| 5237 | const unsigned int count = this->count_; |
| 5238 | for (unsigned int i = 0; |
| 5239 | i < count; |
| 5240 | ++i, |
| 5241 | pov += sizeof(plt_entry), |
| 5242 | got_pov += 4, |
| 5243 | plt_offset += sizeof(plt_entry), |
| 5244 | plt_rel_offset += rel_size, |
| 5245 | got_offset += 4) |
| 5246 | { |
| 5247 | // Set and adjust the PLT entry itself. |
| 5248 | int32_t offset = ((got_address + got_offset) |
| 5249 | - (plt_address + plt_offset + 8)); |
| 5250 | |
| 5251 | gold_assert(offset >= 0 && offset < 0x0fffffff); |
| 5252 | uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff); |
| 5253 | elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0); |
| 5254 | uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff); |
| 5255 | elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1); |
| 5256 | uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff); |
| 5257 | elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2); |
| 5258 | |
| 5259 | // Set the entry in the GOT. |
| 5260 | elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address); |
| 5261 | } |
| 5262 | |
| 5263 | gold_assert(static_cast<section_size_type>(pov - oview) == oview_size); |
| 5264 | gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size); |
| 5265 | |
| 5266 | of->write_output_view(offset, oview_size, oview); |
| 5267 | of->write_output_view(got_file_offset, got_size, got_view); |
| 5268 | } |
| 5269 | |
| 5270 | // Create a PLT entry for a global symbol. |
| 5271 | |
| 5272 | template<bool big_endian> |
| 5273 | void |
| 5274 | Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout, |
| 5275 | Symbol* gsym) |
| 5276 | { |
| 5277 | if (gsym->has_plt_offset()) |
| 5278 | return; |
| 5279 | |
| 5280 | if (this->plt_ == NULL) |
| 5281 | { |
| 5282 | // Create the GOT sections first. |
| 5283 | this->got_section(symtab, layout); |
| 5284 | |
| 5285 | this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_); |
| 5286 | layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS, |
| 5287 | (elfcpp::SHF_ALLOC |
| 5288 | | elfcpp::SHF_EXECINSTR), |
| 5289 | this->plt_, false, false, false, false); |
| 5290 | } |
| 5291 | this->plt_->add_entry(gsym); |
| 5292 | } |
| 5293 | |
| 5294 | // Report an unsupported relocation against a local symbol. |
| 5295 | |
| 5296 | template<bool big_endian> |
| 5297 | void |
| 5298 | Target_arm<big_endian>::Scan::unsupported_reloc_local( |
| 5299 | Sized_relobj<32, big_endian>* object, |
| 5300 | unsigned int r_type) |
| 5301 | { |
| 5302 | gold_error(_("%s: unsupported reloc %u against local symbol"), |
| 5303 | object->name().c_str(), r_type); |
| 5304 | } |
| 5305 | |
| 5306 | // We are about to emit a dynamic relocation of type R_TYPE. If the |
| 5307 | // dynamic linker does not support it, issue an error. The GNU linker |
| 5308 | // only issues a non-PIC error for an allocated read-only section. |
| 5309 | // Here we know the section is allocated, but we don't know that it is |
| 5310 | // read-only. But we check for all the relocation types which the |
| 5311 | // glibc dynamic linker supports, so it seems appropriate to issue an |
| 5312 | // error even if the section is not read-only. |
| 5313 | |
| 5314 | template<bool big_endian> |
| 5315 | void |
| 5316 | Target_arm<big_endian>::Scan::check_non_pic(Relobj* object, |
| 5317 | unsigned int r_type) |
| 5318 | { |
| 5319 | switch (r_type) |
| 5320 | { |
| 5321 | // These are the relocation types supported by glibc for ARM. |
| 5322 | case elfcpp::R_ARM_RELATIVE: |
| 5323 | case elfcpp::R_ARM_COPY: |
| 5324 | case elfcpp::R_ARM_GLOB_DAT: |
| 5325 | case elfcpp::R_ARM_JUMP_SLOT: |
| 5326 | case elfcpp::R_ARM_ABS32: |
| 5327 | case elfcpp::R_ARM_ABS32_NOI: |
| 5328 | case elfcpp::R_ARM_PC24: |
| 5329 | // FIXME: The following 3 types are not supported by Android's dynamic |
| 5330 | // linker. |
| 5331 | case elfcpp::R_ARM_TLS_DTPMOD32: |
| 5332 | case elfcpp::R_ARM_TLS_DTPOFF32: |
| 5333 | case elfcpp::R_ARM_TLS_TPOFF32: |
| 5334 | return; |
| 5335 | |
| 5336 | default: |
| 5337 | // This prevents us from issuing more than one error per reloc |
| 5338 | // section. But we can still wind up issuing more than one |
| 5339 | // error per object file. |
| 5340 | if (this->issued_non_pic_error_) |
| 5341 | return; |
| 5342 | object->error(_("requires unsupported dynamic reloc; " |
| 5343 | "recompile with -fPIC")); |
| 5344 | this->issued_non_pic_error_ = true; |
| 5345 | return; |
| 5346 | |
| 5347 | case elfcpp::R_ARM_NONE: |
| 5348 | gold_unreachable(); |
| 5349 | } |
| 5350 | } |
| 5351 | |
| 5352 | // Scan a relocation for a local symbol. |
| 5353 | // FIXME: This only handles a subset of relocation types used by Android |
| 5354 | // on ARM v5te devices. |
| 5355 | |
| 5356 | template<bool big_endian> |
| 5357 | inline void |
| 5358 | Target_arm<big_endian>::Scan::local(Symbol_table* symtab, |
| 5359 | Layout* layout, |
| 5360 | Target_arm* target, |
| 5361 | Sized_relobj<32, big_endian>* object, |
| 5362 | unsigned int data_shndx, |
| 5363 | Output_section* output_section, |
| 5364 | const elfcpp::Rel<32, big_endian>& reloc, |
| 5365 | unsigned int r_type, |
| 5366 | const elfcpp::Sym<32, big_endian>&) |
| 5367 | { |
| 5368 | r_type = get_real_reloc_type(r_type); |
| 5369 | switch (r_type) |
| 5370 | { |
| 5371 | case elfcpp::R_ARM_NONE: |
| 5372 | break; |
| 5373 | |
| 5374 | case elfcpp::R_ARM_ABS32: |
| 5375 | case elfcpp::R_ARM_ABS32_NOI: |
| 5376 | // If building a shared library (or a position-independent |
| 5377 | // executable), we need to create a dynamic relocation for |
| 5378 | // this location. The relocation applied at link time will |
| 5379 | // apply the link-time value, so we flag the location with |
| 5380 | // an R_ARM_RELATIVE relocation so the dynamic loader can |
| 5381 | // relocate it easily. |
| 5382 | if (parameters->options().output_is_position_independent()) |
| 5383 | { |
| 5384 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 5385 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); |
| 5386 | // If we are to add more other reloc types than R_ARM_ABS32, |
| 5387 | // we need to add check_non_pic(object, r_type) here. |
| 5388 | rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE, |
| 5389 | output_section, data_shndx, |
| 5390 | reloc.get_r_offset()); |
| 5391 | } |
| 5392 | break; |
| 5393 | |
| 5394 | case elfcpp::R_ARM_REL32: |
| 5395 | case elfcpp::R_ARM_THM_CALL: |
| 5396 | case elfcpp::R_ARM_CALL: |
| 5397 | case elfcpp::R_ARM_PREL31: |
| 5398 | case elfcpp::R_ARM_JUMP24: |
| 5399 | case elfcpp::R_ARM_THM_JUMP24: |
| 5400 | case elfcpp::R_ARM_THM_JUMP19: |
| 5401 | case elfcpp::R_ARM_PLT32: |
| 5402 | case elfcpp::R_ARM_THM_ABS5: |
| 5403 | case elfcpp::R_ARM_ABS8: |
| 5404 | case elfcpp::R_ARM_ABS12: |
| 5405 | case elfcpp::R_ARM_ABS16: |
| 5406 | case elfcpp::R_ARM_BASE_ABS: |
| 5407 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 5408 | case elfcpp::R_ARM_MOVT_ABS: |
| 5409 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 5410 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 5411 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 5412 | case elfcpp::R_ARM_MOVT_PREL: |
| 5413 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 5414 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 5415 | case elfcpp::R_ARM_THM_JUMP6: |
| 5416 | case elfcpp::R_ARM_THM_JUMP8: |
| 5417 | case elfcpp::R_ARM_THM_JUMP11: |
| 5418 | case elfcpp::R_ARM_V4BX: |
| 5419 | break; |
| 5420 | |
| 5421 | case elfcpp::R_ARM_GOTOFF32: |
| 5422 | // We need a GOT section: |
| 5423 | target->got_section(symtab, layout); |
| 5424 | break; |
| 5425 | |
| 5426 | case elfcpp::R_ARM_BASE_PREL: |
| 5427 | // FIXME: What about this? |
| 5428 | break; |
| 5429 | |
| 5430 | case elfcpp::R_ARM_GOT_BREL: |
| 5431 | case elfcpp::R_ARM_GOT_PREL: |
| 5432 | { |
| 5433 | // The symbol requires a GOT entry. |
| 5434 | Output_data_got<32, big_endian>* got = |
| 5435 | target->got_section(symtab, layout); |
| 5436 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); |
| 5437 | if (got->add_local(object, r_sym, GOT_TYPE_STANDARD)) |
| 5438 | { |
| 5439 | // If we are generating a shared object, we need to add a |
| 5440 | // dynamic RELATIVE relocation for this symbol's GOT entry. |
| 5441 | if (parameters->options().output_is_position_independent()) |
| 5442 | { |
| 5443 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 5444 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); |
| 5445 | rel_dyn->add_local_relative( |
| 5446 | object, r_sym, elfcpp::R_ARM_RELATIVE, got, |
| 5447 | object->local_got_offset(r_sym, GOT_TYPE_STANDARD)); |
| 5448 | } |
| 5449 | } |
| 5450 | } |
| 5451 | break; |
| 5452 | |
| 5453 | case elfcpp::R_ARM_TARGET1: |
| 5454 | // This should have been mapped to another type already. |
| 5455 | // Fall through. |
| 5456 | case elfcpp::R_ARM_COPY: |
| 5457 | case elfcpp::R_ARM_GLOB_DAT: |
| 5458 | case elfcpp::R_ARM_JUMP_SLOT: |
| 5459 | case elfcpp::R_ARM_RELATIVE: |
| 5460 | // These are relocations which should only be seen by the |
| 5461 | // dynamic linker, and should never be seen here. |
| 5462 | gold_error(_("%s: unexpected reloc %u in object file"), |
| 5463 | object->name().c_str(), r_type); |
| 5464 | break; |
| 5465 | |
| 5466 | default: |
| 5467 | unsupported_reloc_local(object, r_type); |
| 5468 | break; |
| 5469 | } |
| 5470 | } |
| 5471 | |
| 5472 | // Report an unsupported relocation against a global symbol. |
| 5473 | |
| 5474 | template<bool big_endian> |
| 5475 | void |
| 5476 | Target_arm<big_endian>::Scan::unsupported_reloc_global( |
| 5477 | Sized_relobj<32, big_endian>* object, |
| 5478 | unsigned int r_type, |
| 5479 | Symbol* gsym) |
| 5480 | { |
| 5481 | gold_error(_("%s: unsupported reloc %u against global symbol %s"), |
| 5482 | object->name().c_str(), r_type, gsym->demangled_name().c_str()); |
| 5483 | } |
| 5484 | |
| 5485 | // Scan a relocation for a global symbol. |
| 5486 | // FIXME: This only handles a subset of relocation types used by Android |
| 5487 | // on ARM v5te devices. |
| 5488 | |
| 5489 | template<bool big_endian> |
| 5490 | inline void |
| 5491 | Target_arm<big_endian>::Scan::global(Symbol_table* symtab, |
| 5492 | Layout* layout, |
| 5493 | Target_arm* target, |
| 5494 | Sized_relobj<32, big_endian>* object, |
| 5495 | unsigned int data_shndx, |
| 5496 | Output_section* output_section, |
| 5497 | const elfcpp::Rel<32, big_endian>& reloc, |
| 5498 | unsigned int r_type, |
| 5499 | Symbol* gsym) |
| 5500 | { |
| 5501 | r_type = get_real_reloc_type(r_type); |
| 5502 | switch (r_type) |
| 5503 | { |
| 5504 | case elfcpp::R_ARM_NONE: |
| 5505 | break; |
| 5506 | |
| 5507 | case elfcpp::R_ARM_ABS32: |
| 5508 | case elfcpp::R_ARM_ABS32_NOI: |
| 5509 | { |
| 5510 | // Make a dynamic relocation if necessary. |
| 5511 | if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF)) |
| 5512 | { |
| 5513 | if (target->may_need_copy_reloc(gsym)) |
| 5514 | { |
| 5515 | target->copy_reloc(symtab, layout, object, |
| 5516 | data_shndx, output_section, gsym, reloc); |
| 5517 | } |
| 5518 | else if (gsym->can_use_relative_reloc(false)) |
| 5519 | { |
| 5520 | // If we are to add more other reloc types than R_ARM_ABS32, |
| 5521 | // we need to add check_non_pic(object, r_type) here. |
| 5522 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 5523 | rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE, |
| 5524 | output_section, object, |
| 5525 | data_shndx, reloc.get_r_offset()); |
| 5526 | } |
| 5527 | else |
| 5528 | { |
| 5529 | // If we are to add more other reloc types than R_ARM_ABS32, |
| 5530 | // we need to add check_non_pic(object, r_type) here. |
| 5531 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 5532 | rel_dyn->add_global(gsym, r_type, output_section, object, |
| 5533 | data_shndx, reloc.get_r_offset()); |
| 5534 | } |
| 5535 | } |
| 5536 | } |
| 5537 | break; |
| 5538 | |
| 5539 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 5540 | case elfcpp::R_ARM_MOVT_ABS: |
| 5541 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 5542 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 5543 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 5544 | case elfcpp::R_ARM_MOVT_PREL: |
| 5545 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 5546 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 5547 | case elfcpp::R_ARM_THM_JUMP6: |
| 5548 | case elfcpp::R_ARM_THM_JUMP8: |
| 5549 | case elfcpp::R_ARM_THM_JUMP11: |
| 5550 | case elfcpp::R_ARM_V4BX: |
| 5551 | break; |
| 5552 | |
| 5553 | case elfcpp::R_ARM_THM_ABS5: |
| 5554 | case elfcpp::R_ARM_ABS8: |
| 5555 | case elfcpp::R_ARM_ABS12: |
| 5556 | case elfcpp::R_ARM_ABS16: |
| 5557 | case elfcpp::R_ARM_BASE_ABS: |
| 5558 | { |
| 5559 | // No dynamic relocs of this kinds. |
| 5560 | // Report the error in case of PIC. |
| 5561 | int flags = Symbol::NON_PIC_REF; |
| 5562 | if (gsym->type() == elfcpp::STT_FUNC |
| 5563 | || gsym->type() == elfcpp::STT_ARM_TFUNC) |
| 5564 | flags |= Symbol::FUNCTION_CALL; |
| 5565 | if (gsym->needs_dynamic_reloc(flags)) |
| 5566 | check_non_pic(object, r_type); |
| 5567 | } |
| 5568 | break; |
| 5569 | |
| 5570 | case elfcpp::R_ARM_REL32: |
| 5571 | case elfcpp::R_ARM_PREL31: |
| 5572 | { |
| 5573 | // Make a dynamic relocation if necessary. |
| 5574 | int flags = Symbol::NON_PIC_REF; |
| 5575 | if (gsym->needs_dynamic_reloc(flags)) |
| 5576 | { |
| 5577 | if (target->may_need_copy_reloc(gsym)) |
| 5578 | { |
| 5579 | target->copy_reloc(symtab, layout, object, |
| 5580 | data_shndx, output_section, gsym, reloc); |
| 5581 | } |
| 5582 | else |
| 5583 | { |
| 5584 | check_non_pic(object, r_type); |
| 5585 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 5586 | rel_dyn->add_global(gsym, r_type, output_section, object, |
| 5587 | data_shndx, reloc.get_r_offset()); |
| 5588 | } |
| 5589 | } |
| 5590 | } |
| 5591 | break; |
| 5592 | |
| 5593 | case elfcpp::R_ARM_JUMP24: |
| 5594 | case elfcpp::R_ARM_THM_JUMP24: |
| 5595 | case elfcpp::R_ARM_THM_JUMP19: |
| 5596 | case elfcpp::R_ARM_CALL: |
| 5597 | case elfcpp::R_ARM_THM_CALL: |
| 5598 | |
| 5599 | if (Target_arm<big_endian>::Scan::symbol_needs_plt_entry(gsym)) |
| 5600 | target->make_plt_entry(symtab, layout, gsym); |
| 5601 | else |
| 5602 | { |
| 5603 | // Check to see if this is a function that would need a PLT |
| 5604 | // but does not get one because the function symbol is untyped. |
| 5605 | // This happens in assembly code missing a proper .type directive. |
| 5606 | if ((!gsym->is_undefined() || parameters->options().shared()) |
| 5607 | && !parameters->doing_static_link() |
| 5608 | && gsym->type() == elfcpp::STT_NOTYPE |
| 5609 | && (gsym->is_from_dynobj() |
| 5610 | || gsym->is_undefined() |
| 5611 | || gsym->is_preemptible())) |
| 5612 | gold_error(_("%s is not a function."), |
| 5613 | gsym->demangled_name().c_str()); |
| 5614 | } |
| 5615 | break; |
| 5616 | |
| 5617 | case elfcpp::R_ARM_PLT32: |
| 5618 | // If the symbol is fully resolved, this is just a relative |
| 5619 | // local reloc. Otherwise we need a PLT entry. |
| 5620 | if (gsym->final_value_is_known()) |
| 5621 | break; |
| 5622 | // If building a shared library, we can also skip the PLT entry |
| 5623 | // if the symbol is defined in the output file and is protected |
| 5624 | // or hidden. |
| 5625 | if (gsym->is_defined() |
| 5626 | && !gsym->is_from_dynobj() |
| 5627 | && !gsym->is_preemptible()) |
| 5628 | break; |
| 5629 | target->make_plt_entry(symtab, layout, gsym); |
| 5630 | break; |
| 5631 | |
| 5632 | case elfcpp::R_ARM_GOTOFF32: |
| 5633 | // We need a GOT section. |
| 5634 | target->got_section(symtab, layout); |
| 5635 | break; |
| 5636 | |
| 5637 | case elfcpp::R_ARM_BASE_PREL: |
| 5638 | // FIXME: What about this? |
| 5639 | break; |
| 5640 | |
| 5641 | case elfcpp::R_ARM_GOT_BREL: |
| 5642 | case elfcpp::R_ARM_GOT_PREL: |
| 5643 | { |
| 5644 | // The symbol requires a GOT entry. |
| 5645 | Output_data_got<32, big_endian>* got = |
| 5646 | target->got_section(symtab, layout); |
| 5647 | if (gsym->final_value_is_known()) |
| 5648 | got->add_global(gsym, GOT_TYPE_STANDARD); |
| 5649 | else |
| 5650 | { |
| 5651 | // If this symbol is not fully resolved, we need to add a |
| 5652 | // GOT entry with a dynamic relocation. |
| 5653 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 5654 | if (gsym->is_from_dynobj() |
| 5655 | || gsym->is_undefined() |
| 5656 | || gsym->is_preemptible()) |
| 5657 | got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, |
| 5658 | rel_dyn, elfcpp::R_ARM_GLOB_DAT); |
| 5659 | else |
| 5660 | { |
| 5661 | if (got->add_global(gsym, GOT_TYPE_STANDARD)) |
| 5662 | rel_dyn->add_global_relative( |
| 5663 | gsym, elfcpp::R_ARM_RELATIVE, got, |
| 5664 | gsym->got_offset(GOT_TYPE_STANDARD)); |
| 5665 | } |
| 5666 | } |
| 5667 | } |
| 5668 | break; |
| 5669 | |
| 5670 | case elfcpp::R_ARM_TARGET1: |
| 5671 | // This should have been mapped to another type already. |
| 5672 | // Fall through. |
| 5673 | case elfcpp::R_ARM_COPY: |
| 5674 | case elfcpp::R_ARM_GLOB_DAT: |
| 5675 | case elfcpp::R_ARM_JUMP_SLOT: |
| 5676 | case elfcpp::R_ARM_RELATIVE: |
| 5677 | // These are relocations which should only be seen by the |
| 5678 | // dynamic linker, and should never be seen here. |
| 5679 | gold_error(_("%s: unexpected reloc %u in object file"), |
| 5680 | object->name().c_str(), r_type); |
| 5681 | break; |
| 5682 | |
| 5683 | default: |
| 5684 | unsupported_reloc_global(object, r_type, gsym); |
| 5685 | break; |
| 5686 | } |
| 5687 | } |
| 5688 | |
| 5689 | // Process relocations for gc. |
| 5690 | |
| 5691 | template<bool big_endian> |
| 5692 | void |
| 5693 | Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab, |
| 5694 | Layout* layout, |
| 5695 | Sized_relobj<32, big_endian>* object, |
| 5696 | unsigned int data_shndx, |
| 5697 | unsigned int, |
| 5698 | const unsigned char* prelocs, |
| 5699 | size_t reloc_count, |
| 5700 | Output_section* output_section, |
| 5701 | bool needs_special_offset_handling, |
| 5702 | size_t local_symbol_count, |
| 5703 | const unsigned char* plocal_symbols) |
| 5704 | { |
| 5705 | typedef Target_arm<big_endian> Arm; |
| 5706 | typedef typename Target_arm<big_endian>::Scan Scan; |
| 5707 | |
| 5708 | gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>( |
| 5709 | symtab, |
| 5710 | layout, |
| 5711 | this, |
| 5712 | object, |
| 5713 | data_shndx, |
| 5714 | prelocs, |
| 5715 | reloc_count, |
| 5716 | output_section, |
| 5717 | needs_special_offset_handling, |
| 5718 | local_symbol_count, |
| 5719 | plocal_symbols); |
| 5720 | } |
| 5721 | |
| 5722 | // Scan relocations for a section. |
| 5723 | |
| 5724 | template<bool big_endian> |
| 5725 | void |
| 5726 | Target_arm<big_endian>::scan_relocs(Symbol_table* symtab, |
| 5727 | Layout* layout, |
| 5728 | Sized_relobj<32, big_endian>* object, |
| 5729 | unsigned int data_shndx, |
| 5730 | unsigned int sh_type, |
| 5731 | const unsigned char* prelocs, |
| 5732 | size_t reloc_count, |
| 5733 | Output_section* output_section, |
| 5734 | bool needs_special_offset_handling, |
| 5735 | size_t local_symbol_count, |
| 5736 | const unsigned char* plocal_symbols) |
| 5737 | { |
| 5738 | typedef typename Target_arm<big_endian>::Scan Scan; |
| 5739 | if (sh_type == elfcpp::SHT_RELA) |
| 5740 | { |
| 5741 | gold_error(_("%s: unsupported RELA reloc section"), |
| 5742 | object->name().c_str()); |
| 5743 | return; |
| 5744 | } |
| 5745 | |
| 5746 | gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>( |
| 5747 | symtab, |
| 5748 | layout, |
| 5749 | this, |
| 5750 | object, |
| 5751 | data_shndx, |
| 5752 | prelocs, |
| 5753 | reloc_count, |
| 5754 | output_section, |
| 5755 | needs_special_offset_handling, |
| 5756 | local_symbol_count, |
| 5757 | plocal_symbols); |
| 5758 | } |
| 5759 | |
| 5760 | // Finalize the sections. |
| 5761 | |
| 5762 | template<bool big_endian> |
| 5763 | void |
| 5764 | Target_arm<big_endian>::do_finalize_sections( |
| 5765 | Layout* layout, |
| 5766 | const Input_objects* input_objects, |
| 5767 | Symbol_table* symtab) |
| 5768 | { |
| 5769 | // Merge processor-specific flags. |
| 5770 | for (Input_objects::Relobj_iterator p = input_objects->relobj_begin(); |
| 5771 | p != input_objects->relobj_end(); |
| 5772 | ++p) |
| 5773 | { |
| 5774 | Arm_relobj<big_endian>* arm_relobj = |
| 5775 | Arm_relobj<big_endian>::as_arm_relobj(*p); |
| 5776 | this->merge_processor_specific_flags( |
| 5777 | arm_relobj->name(), |
| 5778 | arm_relobj->processor_specific_flags()); |
| 5779 | this->merge_object_attributes(arm_relobj->name().c_str(), |
| 5780 | arm_relobj->attributes_section_data()); |
| 5781 | |
| 5782 | } |
| 5783 | |
| 5784 | for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin(); |
| 5785 | p != input_objects->dynobj_end(); |
| 5786 | ++p) |
| 5787 | { |
| 5788 | Arm_dynobj<big_endian>* arm_dynobj = |
| 5789 | Arm_dynobj<big_endian>::as_arm_dynobj(*p); |
| 5790 | this->merge_processor_specific_flags( |
| 5791 | arm_dynobj->name(), |
| 5792 | arm_dynobj->processor_specific_flags()); |
| 5793 | this->merge_object_attributes(arm_dynobj->name().c_str(), |
| 5794 | arm_dynobj->attributes_section_data()); |
| 5795 | } |
| 5796 | |
| 5797 | // Check BLX use. |
| 5798 | const Object_attribute* cpu_arch_attr = |
| 5799 | this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch); |
| 5800 | if (cpu_arch_attr->int_value() > elfcpp::TAG_CPU_ARCH_V4) |
| 5801 | this->set_may_use_blx(true); |
| 5802 | |
| 5803 | // Check if we need to use Cortex-A8 workaround. |
| 5804 | if (parameters->options().user_set_fix_cortex_a8()) |
| 5805 | this->fix_cortex_a8_ = parameters->options().fix_cortex_a8(); |
| 5806 | else |
| 5807 | { |
| 5808 | // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on |
| 5809 | // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown |
| 5810 | // profile. |
| 5811 | const Object_attribute* cpu_arch_profile_attr = |
| 5812 | this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile); |
| 5813 | this->fix_cortex_a8_ = |
| 5814 | (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7 |
| 5815 | && (cpu_arch_profile_attr->int_value() == 'A' |
| 5816 | || cpu_arch_profile_attr->int_value() == 0)); |
| 5817 | } |
| 5818 | |
| 5819 | // Check if we can use V4BX interworking. |
| 5820 | // The V4BX interworking stub contains BX instruction, |
| 5821 | // which is not specified for some profiles. |
| 5822 | if (this->fix_v4bx() == 2 && !this->may_use_blx()) |
| 5823 | gold_error(_("unable to provide V4BX reloc interworking fix up; " |
| 5824 | "the target profile does not support BX instruction")); |
| 5825 | |
| 5826 | // Fill in some more dynamic tags. |
| 5827 | const Reloc_section* rel_plt = (this->plt_ == NULL |
| 5828 | ? NULL |
| 5829 | : this->plt_->rel_plt()); |
| 5830 | layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt, |
| 5831 | this->rel_dyn_, true); |
| 5832 | |
| 5833 | // Emit any relocs we saved in an attempt to avoid generating COPY |
| 5834 | // relocs. |
| 5835 | if (this->copy_relocs_.any_saved_relocs()) |
| 5836 | this->copy_relocs_.emit(this->rel_dyn_section(layout)); |
| 5837 | |
| 5838 | // Handle the .ARM.exidx section. |
| 5839 | Output_section* exidx_section = layout->find_output_section(".ARM.exidx"); |
| 5840 | if (exidx_section != NULL |
| 5841 | && exidx_section->type() == elfcpp::SHT_ARM_EXIDX |
| 5842 | && !parameters->options().relocatable()) |
| 5843 | { |
| 5844 | // Create __exidx_start and __exdix_end symbols. |
| 5845 | symtab->define_in_output_data("__exidx_start", NULL, |
| 5846 | Symbol_table::PREDEFINED, |
| 5847 | exidx_section, 0, 0, elfcpp::STT_OBJECT, |
| 5848 | elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0, |
| 5849 | false, true); |
| 5850 | symtab->define_in_output_data("__exidx_end", NULL, |
| 5851 | Symbol_table::PREDEFINED, |
| 5852 | exidx_section, 0, 0, elfcpp::STT_OBJECT, |
| 5853 | elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0, |
| 5854 | true, true); |
| 5855 | |
| 5856 | // For the ARM target, we need to add a PT_ARM_EXIDX segment for |
| 5857 | // the .ARM.exidx section. |
| 5858 | if (!layout->script_options()->saw_phdrs_clause()) |
| 5859 | { |
| 5860 | gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0) |
| 5861 | == NULL); |
| 5862 | Output_segment* exidx_segment = |
| 5863 | layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R); |
| 5864 | exidx_segment->add_output_section(exidx_section, elfcpp::PF_R, |
| 5865 | false); |
| 5866 | } |
| 5867 | } |
| 5868 | |
| 5869 | // Create an .ARM.attributes section if there is not one already. |
| 5870 | Output_attributes_section_data* attributes_section = |
| 5871 | new Output_attributes_section_data(*this->attributes_section_data_); |
| 5872 | layout->add_output_section_data(".ARM.attributes", |
| 5873 | elfcpp::SHT_ARM_ATTRIBUTES, 0, |
| 5874 | attributes_section, false, false, false, |
| 5875 | false); |
| 5876 | } |
| 5877 | |
| 5878 | // Return whether a direct absolute static relocation needs to be applied. |
| 5879 | // In cases where Scan::local() or Scan::global() has created |
| 5880 | // a dynamic relocation other than R_ARM_RELATIVE, the addend |
| 5881 | // of the relocation is carried in the data, and we must not |
| 5882 | // apply the static relocation. |
| 5883 | |
| 5884 | template<bool big_endian> |
| 5885 | inline bool |
| 5886 | Target_arm<big_endian>::Relocate::should_apply_static_reloc( |
| 5887 | const Sized_symbol<32>* gsym, |
| 5888 | int ref_flags, |
| 5889 | bool is_32bit, |
| 5890 | Output_section* output_section) |
| 5891 | { |
| 5892 | // If the output section is not allocated, then we didn't call |
| 5893 | // scan_relocs, we didn't create a dynamic reloc, and we must apply |
| 5894 | // the reloc here. |
| 5895 | if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0) |
| 5896 | return true; |
| 5897 | |
| 5898 | // For local symbols, we will have created a non-RELATIVE dynamic |
| 5899 | // relocation only if (a) the output is position independent, |
| 5900 | // (b) the relocation is absolute (not pc- or segment-relative), and |
| 5901 | // (c) the relocation is not 32 bits wide. |
| 5902 | if (gsym == NULL) |
| 5903 | return !(parameters->options().output_is_position_independent() |
| 5904 | && (ref_flags & Symbol::ABSOLUTE_REF) |
| 5905 | && !is_32bit); |
| 5906 | |
| 5907 | // For global symbols, we use the same helper routines used in the |
| 5908 | // scan pass. If we did not create a dynamic relocation, or if we |
| 5909 | // created a RELATIVE dynamic relocation, we should apply the static |
| 5910 | // relocation. |
| 5911 | bool has_dyn = gsym->needs_dynamic_reloc(ref_flags); |
| 5912 | bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF) |
| 5913 | && gsym->can_use_relative_reloc(ref_flags |
| 5914 | & Symbol::FUNCTION_CALL); |
| 5915 | return !has_dyn || is_rel; |
| 5916 | } |
| 5917 | |
| 5918 | // Perform a relocation. |
| 5919 | |
| 5920 | template<bool big_endian> |
| 5921 | inline bool |
| 5922 | Target_arm<big_endian>::Relocate::relocate( |
| 5923 | const Relocate_info<32, big_endian>* relinfo, |
| 5924 | Target_arm* target, |
| 5925 | Output_section *output_section, |
| 5926 | size_t relnum, |
| 5927 | const elfcpp::Rel<32, big_endian>& rel, |
| 5928 | unsigned int r_type, |
| 5929 | const Sized_symbol<32>* gsym, |
| 5930 | const Symbol_value<32>* psymval, |
| 5931 | unsigned char* view, |
| 5932 | Arm_address address, |
| 5933 | section_size_type /* view_size */ ) |
| 5934 | { |
| 5935 | typedef Arm_relocate_functions<big_endian> Arm_relocate_functions; |
| 5936 | |
| 5937 | r_type = get_real_reloc_type(r_type); |
| 5938 | |
| 5939 | const Arm_relobj<big_endian>* object = |
| 5940 | Arm_relobj<big_endian>::as_arm_relobj(relinfo->object); |
| 5941 | |
| 5942 | // If the final branch target of a relocation is THUMB instruction, this |
| 5943 | // is 1. Otherwise it is 0. |
| 5944 | Arm_address thumb_bit = 0; |
| 5945 | Symbol_value<32> symval; |
| 5946 | bool is_weakly_undefined_without_plt = false; |
| 5947 | if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs) |
| 5948 | { |
| 5949 | if (gsym != NULL) |
| 5950 | { |
| 5951 | // This is a global symbol. Determine if we use PLT and if the |
| 5952 | // final target is THUMB. |
| 5953 | if (gsym->use_plt_offset(reloc_is_non_pic(r_type))) |
| 5954 | { |
| 5955 | // This uses a PLT, change the symbol value. |
| 5956 | symval.set_output_value(target->plt_section()->address() |
| 5957 | + gsym->plt_offset()); |
| 5958 | psymval = &symval; |
| 5959 | } |
| 5960 | else if (gsym->is_weak_undefined()) |
| 5961 | { |
| 5962 | // This is a weakly undefined symbol and we do not use PLT |
| 5963 | // for this relocation. A branch targeting this symbol will |
| 5964 | // be converted into an NOP. |
| 5965 | is_weakly_undefined_without_plt = true; |
| 5966 | } |
| 5967 | else |
| 5968 | { |
| 5969 | // Set thumb bit if symbol: |
| 5970 | // -Has type STT_ARM_TFUNC or |
| 5971 | // -Has type STT_FUNC, is defined and with LSB in value set. |
| 5972 | thumb_bit = |
| 5973 | (((gsym->type() == elfcpp::STT_ARM_TFUNC) |
| 5974 | || (gsym->type() == elfcpp::STT_FUNC |
| 5975 | && !gsym->is_undefined() |
| 5976 | && ((psymval->value(object, 0) & 1) != 0))) |
| 5977 | ? 1 |
| 5978 | : 0); |
| 5979 | } |
| 5980 | } |
| 5981 | else |
| 5982 | { |
| 5983 | // This is a local symbol. Determine if the final target is THUMB. |
| 5984 | // We saved this information when all the local symbols were read. |
| 5985 | elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info(); |
| 5986 | unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info); |
| 5987 | thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0; |
| 5988 | } |
| 5989 | } |
| 5990 | else |
| 5991 | { |
| 5992 | // This is a fake relocation synthesized for a stub. It does not have |
| 5993 | // a real symbol. We just look at the LSB of the symbol value to |
| 5994 | // determine if the target is THUMB or not. |
| 5995 | thumb_bit = ((psymval->value(object, 0) & 1) != 0); |
| 5996 | } |
| 5997 | |
| 5998 | // Strip LSB if this points to a THUMB target. |
| 5999 | if (thumb_bit != 0 |
| 6000 | && Target_arm<big_endian>::reloc_uses_thumb_bit(r_type) |
| 6001 | && ((psymval->value(object, 0) & 1) != 0)) |
| 6002 | { |
| 6003 | Arm_address stripped_value = |
| 6004 | psymval->value(object, 0) & ~static_cast<Arm_address>(1); |
| 6005 | symval.set_output_value(stripped_value); |
| 6006 | psymval = &symval; |
| 6007 | } |
| 6008 | |
| 6009 | // Get the GOT offset if needed. |
| 6010 | // The GOT pointer points to the end of the GOT section. |
| 6011 | // We need to subtract the size of the GOT section to get |
| 6012 | // the actual offset to use in the relocation. |
| 6013 | bool have_got_offset = false; |
| 6014 | unsigned int got_offset = 0; |
| 6015 | switch (r_type) |
| 6016 | { |
| 6017 | case elfcpp::R_ARM_GOT_BREL: |
| 6018 | case elfcpp::R_ARM_GOT_PREL: |
| 6019 | if (gsym != NULL) |
| 6020 | { |
| 6021 | gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD)); |
| 6022 | got_offset = (gsym->got_offset(GOT_TYPE_STANDARD) |
| 6023 | - target->got_size()); |
| 6024 | } |
| 6025 | else |
| 6026 | { |
| 6027 | unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info()); |
| 6028 | gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD)); |
| 6029 | got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD) |
| 6030 | - target->got_size()); |
| 6031 | } |
| 6032 | have_got_offset = true; |
| 6033 | break; |
| 6034 | |
| 6035 | default: |
| 6036 | break; |
| 6037 | } |
| 6038 | |
| 6039 | // To look up relocation stubs, we need to pass the symbol table index of |
| 6040 | // a local symbol. |
| 6041 | unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info()); |
| 6042 | |
| 6043 | typename Arm_relocate_functions::Status reloc_status = |
| 6044 | Arm_relocate_functions::STATUS_OKAY; |
| 6045 | switch (r_type) |
| 6046 | { |
| 6047 | case elfcpp::R_ARM_NONE: |
| 6048 | break; |
| 6049 | |
| 6050 | case elfcpp::R_ARM_ABS8: |
| 6051 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 6052 | output_section)) |
| 6053 | reloc_status = Arm_relocate_functions::abs8(view, object, psymval); |
| 6054 | break; |
| 6055 | |
| 6056 | case elfcpp::R_ARM_ABS12: |
| 6057 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 6058 | output_section)) |
| 6059 | reloc_status = Arm_relocate_functions::abs12(view, object, psymval); |
| 6060 | break; |
| 6061 | |
| 6062 | case elfcpp::R_ARM_ABS16: |
| 6063 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 6064 | output_section)) |
| 6065 | reloc_status = Arm_relocate_functions::abs16(view, object, psymval); |
| 6066 | break; |
| 6067 | |
| 6068 | case elfcpp::R_ARM_ABS32: |
| 6069 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 6070 | output_section)) |
| 6071 | reloc_status = Arm_relocate_functions::abs32(view, object, psymval, |
| 6072 | thumb_bit); |
| 6073 | break; |
| 6074 | |
| 6075 | case elfcpp::R_ARM_ABS32_NOI: |
| 6076 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 6077 | output_section)) |
| 6078 | // No thumb bit for this relocation: (S + A) |
| 6079 | reloc_status = Arm_relocate_functions::abs32(view, object, psymval, |
| 6080 | 0); |
| 6081 | break; |
| 6082 | |
| 6083 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 6084 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 6085 | output_section)) |
| 6086 | reloc_status = Arm_relocate_functions::movw_abs_nc(view, object, |
| 6087 | psymval, |
| 6088 | thumb_bit); |
| 6089 | else |
| 6090 | gold_error(_("relocation R_ARM_MOVW_ABS_NC cannot be used when making" |
| 6091 | "a shared object; recompile with -fPIC")); |
| 6092 | break; |
| 6093 | |
| 6094 | case elfcpp::R_ARM_MOVT_ABS: |
| 6095 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 6096 | output_section)) |
| 6097 | reloc_status = Arm_relocate_functions::movt_abs(view, object, psymval); |
| 6098 | else |
| 6099 | gold_error(_("relocation R_ARM_MOVT_ABS cannot be used when making" |
| 6100 | "a shared object; recompile with -fPIC")); |
| 6101 | break; |
| 6102 | |
| 6103 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 6104 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 6105 | output_section)) |
| 6106 | reloc_status = Arm_relocate_functions::thm_movw_abs_nc(view, object, |
| 6107 | psymval, |
| 6108 | thumb_bit); |
| 6109 | else |
| 6110 | gold_error(_("relocation R_ARM_THM_MOVW_ABS_NC cannot be used when" |
| 6111 | "making a shared object; recompile with -fPIC")); |
| 6112 | break; |
| 6113 | |
| 6114 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 6115 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 6116 | output_section)) |
| 6117 | reloc_status = Arm_relocate_functions::thm_movt_abs(view, object, |
| 6118 | psymval); |
| 6119 | else |
| 6120 | gold_error(_("relocation R_ARM_THM_MOVT_ABS cannot be used when" |
| 6121 | "making a shared object; recompile with -fPIC")); |
| 6122 | break; |
| 6123 | |
| 6124 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 6125 | reloc_status = Arm_relocate_functions::movw_prel_nc(view, object, |
| 6126 | psymval, address, |
| 6127 | thumb_bit); |
| 6128 | break; |
| 6129 | |
| 6130 | case elfcpp::R_ARM_MOVT_PREL: |
| 6131 | reloc_status = Arm_relocate_functions::movt_prel(view, object, |
| 6132 | psymval, address); |
| 6133 | break; |
| 6134 | |
| 6135 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 6136 | reloc_status = Arm_relocate_functions::thm_movw_prel_nc(view, object, |
| 6137 | psymval, address, |
| 6138 | thumb_bit); |
| 6139 | break; |
| 6140 | |
| 6141 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 6142 | reloc_status = Arm_relocate_functions::thm_movt_prel(view, object, |
| 6143 | psymval, address); |
| 6144 | break; |
| 6145 | |
| 6146 | case elfcpp::R_ARM_REL32: |
| 6147 | reloc_status = Arm_relocate_functions::rel32(view, object, psymval, |
| 6148 | address, thumb_bit); |
| 6149 | break; |
| 6150 | |
| 6151 | case elfcpp::R_ARM_THM_ABS5: |
| 6152 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 6153 | output_section)) |
| 6154 | reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval); |
| 6155 | break; |
| 6156 | |
| 6157 | case elfcpp::R_ARM_THM_CALL: |
| 6158 | reloc_status = |
| 6159 | Arm_relocate_functions::thm_call(relinfo, view, gsym, object, r_sym, |
| 6160 | psymval, address, thumb_bit, |
| 6161 | is_weakly_undefined_without_plt); |
| 6162 | break; |
| 6163 | |
| 6164 | case elfcpp::R_ARM_XPC25: |
| 6165 | reloc_status = |
| 6166 | Arm_relocate_functions::xpc25(relinfo, view, gsym, object, r_sym, |
| 6167 | psymval, address, thumb_bit, |
| 6168 | is_weakly_undefined_without_plt); |
| 6169 | break; |
| 6170 | |
| 6171 | case elfcpp::R_ARM_THM_XPC22: |
| 6172 | reloc_status = |
| 6173 | Arm_relocate_functions::thm_xpc22(relinfo, view, gsym, object, r_sym, |
| 6174 | psymval, address, thumb_bit, |
| 6175 | is_weakly_undefined_without_plt); |
| 6176 | break; |
| 6177 | |
| 6178 | case elfcpp::R_ARM_GOTOFF32: |
| 6179 | { |
| 6180 | Arm_address got_origin; |
| 6181 | got_origin = target->got_plt_section()->address(); |
| 6182 | reloc_status = Arm_relocate_functions::rel32(view, object, psymval, |
| 6183 | got_origin, thumb_bit); |
| 6184 | } |
| 6185 | break; |
| 6186 | |
| 6187 | case elfcpp::R_ARM_BASE_PREL: |
| 6188 | { |
| 6189 | uint32_t origin; |
| 6190 | // Get the addressing origin of the output segment defining the |
| 6191 | // symbol gsym (AAELF 4.6.1.2 Relocation types) |
| 6192 | gold_assert(gsym != NULL); |
| 6193 | if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT) |
| 6194 | origin = gsym->output_segment()->vaddr(); |
| 6195 | else if (gsym->source () == Symbol::IN_OUTPUT_DATA) |
| 6196 | origin = gsym->output_data()->address(); |
| 6197 | else |
| 6198 | { |
| 6199 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 6200 | _("cannot find origin of R_ARM_BASE_PREL")); |
| 6201 | return true; |
| 6202 | } |
| 6203 | reloc_status = Arm_relocate_functions::base_prel(view, origin, address); |
| 6204 | } |
| 6205 | break; |
| 6206 | |
| 6207 | case elfcpp::R_ARM_BASE_ABS: |
| 6208 | { |
| 6209 | if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 6210 | output_section)) |
| 6211 | break; |
| 6212 | |
| 6213 | uint32_t origin; |
| 6214 | // Get the addressing origin of the output segment defining |
| 6215 | // the symbol gsym (AAELF 4.6.1.2 Relocation types). |
| 6216 | if (gsym == NULL) |
| 6217 | // R_ARM_BASE_ABS with the NULL symbol will give the |
| 6218 | // absolute address of the GOT origin (GOT_ORG) (see ARM IHI |
| 6219 | // 0044C (AAELF): 4.6.1.8 Proxy generating relocations). |
| 6220 | origin = target->got_plt_section()->address(); |
| 6221 | else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT) |
| 6222 | origin = gsym->output_segment()->vaddr(); |
| 6223 | else if (gsym->source () == Symbol::IN_OUTPUT_DATA) |
| 6224 | origin = gsym->output_data()->address(); |
| 6225 | else |
| 6226 | { |
| 6227 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 6228 | _("cannot find origin of R_ARM_BASE_ABS")); |
| 6229 | return true; |
| 6230 | } |
| 6231 | |
| 6232 | reloc_status = Arm_relocate_functions::base_abs(view, origin); |
| 6233 | } |
| 6234 | break; |
| 6235 | |
| 6236 | case elfcpp::R_ARM_GOT_BREL: |
| 6237 | gold_assert(have_got_offset); |
| 6238 | reloc_status = Arm_relocate_functions::got_brel(view, got_offset); |
| 6239 | break; |
| 6240 | |
| 6241 | case elfcpp::R_ARM_GOT_PREL: |
| 6242 | gold_assert(have_got_offset); |
| 6243 | // Get the address origin for GOT PLT, which is allocated right |
| 6244 | // after the GOT section, to calculate an absolute address of |
| 6245 | // the symbol GOT entry (got_origin + got_offset). |
| 6246 | Arm_address got_origin; |
| 6247 | got_origin = target->got_plt_section()->address(); |
| 6248 | reloc_status = Arm_relocate_functions::got_prel(view, |
| 6249 | got_origin + got_offset, |
| 6250 | address); |
| 6251 | break; |
| 6252 | |
| 6253 | case elfcpp::R_ARM_PLT32: |
| 6254 | gold_assert(gsym == NULL |
| 6255 | || gsym->has_plt_offset() |
| 6256 | || gsym->final_value_is_known() |
| 6257 | || (gsym->is_defined() |
| 6258 | && !gsym->is_from_dynobj() |
| 6259 | && !gsym->is_preemptible())); |
| 6260 | reloc_status = |
| 6261 | Arm_relocate_functions::plt32(relinfo, view, gsym, object, r_sym, |
| 6262 | psymval, address, thumb_bit, |
| 6263 | is_weakly_undefined_without_plt); |
| 6264 | break; |
| 6265 | |
| 6266 | case elfcpp::R_ARM_CALL: |
| 6267 | reloc_status = |
| 6268 | Arm_relocate_functions::call(relinfo, view, gsym, object, r_sym, |
| 6269 | psymval, address, thumb_bit, |
| 6270 | is_weakly_undefined_without_plt); |
| 6271 | break; |
| 6272 | |
| 6273 | case elfcpp::R_ARM_JUMP24: |
| 6274 | reloc_status = |
| 6275 | Arm_relocate_functions::jump24(relinfo, view, gsym, object, r_sym, |
| 6276 | psymval, address, thumb_bit, |
| 6277 | is_weakly_undefined_without_plt); |
| 6278 | break; |
| 6279 | |
| 6280 | case elfcpp::R_ARM_THM_JUMP24: |
| 6281 | reloc_status = |
| 6282 | Arm_relocate_functions::thm_jump24(relinfo, view, gsym, object, r_sym, |
| 6283 | psymval, address, thumb_bit, |
| 6284 | is_weakly_undefined_without_plt); |
| 6285 | break; |
| 6286 | |
| 6287 | case elfcpp::R_ARM_THM_JUMP19: |
| 6288 | reloc_status = |
| 6289 | Arm_relocate_functions::thm_jump19(view, object, psymval, address, |
| 6290 | thumb_bit); |
| 6291 | break; |
| 6292 | |
| 6293 | case elfcpp::R_ARM_THM_JUMP6: |
| 6294 | reloc_status = |
| 6295 | Arm_relocate_functions::thm_jump6(view, object, psymval, address); |
| 6296 | break; |
| 6297 | |
| 6298 | case elfcpp::R_ARM_THM_JUMP8: |
| 6299 | reloc_status = |
| 6300 | Arm_relocate_functions::thm_jump8(view, object, psymval, address); |
| 6301 | break; |
| 6302 | |
| 6303 | case elfcpp::R_ARM_THM_JUMP11: |
| 6304 | reloc_status = |
| 6305 | Arm_relocate_functions::thm_jump11(view, object, psymval, address); |
| 6306 | break; |
| 6307 | |
| 6308 | case elfcpp::R_ARM_PREL31: |
| 6309 | reloc_status = Arm_relocate_functions::prel31(view, object, psymval, |
| 6310 | address, thumb_bit); |
| 6311 | break; |
| 6312 | |
| 6313 | case elfcpp::R_ARM_V4BX: |
| 6314 | if (target->fix_v4bx() > 0) |
| 6315 | reloc_status = |
| 6316 | Arm_relocate_functions::v4bx(relinfo, view, object, address, |
| 6317 | (target->fix_v4bx() == 2)); |
| 6318 | break; |
| 6319 | |
| 6320 | case elfcpp::R_ARM_TARGET1: |
| 6321 | // This should have been mapped to another type already. |
| 6322 | // Fall through. |
| 6323 | case elfcpp::R_ARM_COPY: |
| 6324 | case elfcpp::R_ARM_GLOB_DAT: |
| 6325 | case elfcpp::R_ARM_JUMP_SLOT: |
| 6326 | case elfcpp::R_ARM_RELATIVE: |
| 6327 | // These are relocations which should only be seen by the |
| 6328 | // dynamic linker, and should never be seen here. |
| 6329 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 6330 | _("unexpected reloc %u in object file"), |
| 6331 | r_type); |
| 6332 | break; |
| 6333 | |
| 6334 | default: |
| 6335 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 6336 | _("unsupported reloc %u"), |
| 6337 | r_type); |
| 6338 | break; |
| 6339 | } |
| 6340 | |
| 6341 | // Report any errors. |
| 6342 | switch (reloc_status) |
| 6343 | { |
| 6344 | case Arm_relocate_functions::STATUS_OKAY: |
| 6345 | break; |
| 6346 | case Arm_relocate_functions::STATUS_OVERFLOW: |
| 6347 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 6348 | _("relocation overflow in relocation %u"), |
| 6349 | r_type); |
| 6350 | break; |
| 6351 | case Arm_relocate_functions::STATUS_BAD_RELOC: |
| 6352 | gold_error_at_location( |
| 6353 | relinfo, |
| 6354 | relnum, |
| 6355 | rel.get_r_offset(), |
| 6356 | _("unexpected opcode while processing relocation %u"), |
| 6357 | r_type); |
| 6358 | break; |
| 6359 | default: |
| 6360 | gold_unreachable(); |
| 6361 | } |
| 6362 | |
| 6363 | return true; |
| 6364 | } |
| 6365 | |
| 6366 | // Relocate section data. |
| 6367 | |
| 6368 | template<bool big_endian> |
| 6369 | void |
| 6370 | Target_arm<big_endian>::relocate_section( |
| 6371 | const Relocate_info<32, big_endian>* relinfo, |
| 6372 | unsigned int sh_type, |
| 6373 | const unsigned char* prelocs, |
| 6374 | size_t reloc_count, |
| 6375 | Output_section* output_section, |
| 6376 | bool needs_special_offset_handling, |
| 6377 | unsigned char* view, |
| 6378 | Arm_address address, |
| 6379 | section_size_type view_size, |
| 6380 | const Reloc_symbol_changes* reloc_symbol_changes) |
| 6381 | { |
| 6382 | typedef typename Target_arm<big_endian>::Relocate Arm_relocate; |
| 6383 | gold_assert(sh_type == elfcpp::SHT_REL); |
| 6384 | |
| 6385 | Arm_input_section<big_endian>* arm_input_section = |
| 6386 | this->find_arm_input_section(relinfo->object, relinfo->data_shndx); |
| 6387 | |
| 6388 | // This is an ARM input section and the view covers the whole output |
| 6389 | // section. |
| 6390 | if (arm_input_section != NULL) |
| 6391 | { |
| 6392 | gold_assert(needs_special_offset_handling); |
| 6393 | Arm_address section_address = arm_input_section->address(); |
| 6394 | section_size_type section_size = arm_input_section->data_size(); |
| 6395 | |
| 6396 | gold_assert((arm_input_section->address() >= address) |
| 6397 | && ((arm_input_section->address() |
| 6398 | + arm_input_section->data_size()) |
| 6399 | <= (address + view_size))); |
| 6400 | |
| 6401 | off_t offset = section_address - address; |
| 6402 | view += offset; |
| 6403 | address += offset; |
| 6404 | view_size = section_size; |
| 6405 | } |
| 6406 | |
| 6407 | gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL, |
| 6408 | Arm_relocate>( |
| 6409 | relinfo, |
| 6410 | this, |
| 6411 | prelocs, |
| 6412 | reloc_count, |
| 6413 | output_section, |
| 6414 | needs_special_offset_handling, |
| 6415 | view, |
| 6416 | address, |
| 6417 | view_size, |
| 6418 | reloc_symbol_changes); |
| 6419 | } |
| 6420 | |
| 6421 | // Return the size of a relocation while scanning during a relocatable |
| 6422 | // link. |
| 6423 | |
| 6424 | template<bool big_endian> |
| 6425 | unsigned int |
| 6426 | Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc( |
| 6427 | unsigned int r_type, |
| 6428 | Relobj* object) |
| 6429 | { |
| 6430 | r_type = get_real_reloc_type(r_type); |
| 6431 | switch (r_type) |
| 6432 | { |
| 6433 | case elfcpp::R_ARM_NONE: |
| 6434 | return 0; |
| 6435 | |
| 6436 | case elfcpp::R_ARM_ABS8: |
| 6437 | return 1; |
| 6438 | |
| 6439 | case elfcpp::R_ARM_ABS16: |
| 6440 | case elfcpp::R_ARM_THM_ABS5: |
| 6441 | case elfcpp::R_ARM_THM_JUMP6: |
| 6442 | case elfcpp::R_ARM_THM_JUMP8: |
| 6443 | case elfcpp::R_ARM_THM_JUMP11: |
| 6444 | return 2; |
| 6445 | |
| 6446 | case elfcpp::R_ARM_ABS32: |
| 6447 | case elfcpp::R_ARM_ABS32_NOI: |
| 6448 | case elfcpp::R_ARM_ABS12: |
| 6449 | case elfcpp::R_ARM_BASE_ABS: |
| 6450 | case elfcpp::R_ARM_REL32: |
| 6451 | case elfcpp::R_ARM_THM_CALL: |
| 6452 | case elfcpp::R_ARM_GOTOFF32: |
| 6453 | case elfcpp::R_ARM_BASE_PREL: |
| 6454 | case elfcpp::R_ARM_GOT_BREL: |
| 6455 | case elfcpp::R_ARM_GOT_PREL: |
| 6456 | case elfcpp::R_ARM_PLT32: |
| 6457 | case elfcpp::R_ARM_CALL: |
| 6458 | case elfcpp::R_ARM_JUMP24: |
| 6459 | case elfcpp::R_ARM_PREL31: |
| 6460 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 6461 | case elfcpp::R_ARM_MOVT_ABS: |
| 6462 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 6463 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 6464 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 6465 | case elfcpp::R_ARM_MOVT_PREL: |
| 6466 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 6467 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 6468 | case elfcpp::R_ARM_V4BX: |
| 6469 | return 4; |
| 6470 | |
| 6471 | case elfcpp::R_ARM_TARGET1: |
| 6472 | // This should have been mapped to another type already. |
| 6473 | // Fall through. |
| 6474 | case elfcpp::R_ARM_COPY: |
| 6475 | case elfcpp::R_ARM_GLOB_DAT: |
| 6476 | case elfcpp::R_ARM_JUMP_SLOT: |
| 6477 | case elfcpp::R_ARM_RELATIVE: |
| 6478 | // These are relocations which should only be seen by the |
| 6479 | // dynamic linker, and should never be seen here. |
| 6480 | gold_error(_("%s: unexpected reloc %u in object file"), |
| 6481 | object->name().c_str(), r_type); |
| 6482 | return 0; |
| 6483 | |
| 6484 | default: |
| 6485 | object->error(_("unsupported reloc %u in object file"), r_type); |
| 6486 | return 0; |
| 6487 | } |
| 6488 | } |
| 6489 | |
| 6490 | // Scan the relocs during a relocatable link. |
| 6491 | |
| 6492 | template<bool big_endian> |
| 6493 | void |
| 6494 | Target_arm<big_endian>::scan_relocatable_relocs( |
| 6495 | Symbol_table* symtab, |
| 6496 | Layout* layout, |
| 6497 | Sized_relobj<32, big_endian>* object, |
| 6498 | unsigned int data_shndx, |
| 6499 | unsigned int sh_type, |
| 6500 | const unsigned char* prelocs, |
| 6501 | size_t reloc_count, |
| 6502 | Output_section* output_section, |
| 6503 | bool needs_special_offset_handling, |
| 6504 | size_t local_symbol_count, |
| 6505 | const unsigned char* plocal_symbols, |
| 6506 | Relocatable_relocs* rr) |
| 6507 | { |
| 6508 | gold_assert(sh_type == elfcpp::SHT_REL); |
| 6509 | |
| 6510 | typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL, |
| 6511 | Relocatable_size_for_reloc> Scan_relocatable_relocs; |
| 6512 | |
| 6513 | gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL, |
| 6514 | Scan_relocatable_relocs>( |
| 6515 | symtab, |
| 6516 | layout, |
| 6517 | object, |
| 6518 | data_shndx, |
| 6519 | prelocs, |
| 6520 | reloc_count, |
| 6521 | output_section, |
| 6522 | needs_special_offset_handling, |
| 6523 | local_symbol_count, |
| 6524 | plocal_symbols, |
| 6525 | rr); |
| 6526 | } |
| 6527 | |
| 6528 | // Relocate a section during a relocatable link. |
| 6529 | |
| 6530 | template<bool big_endian> |
| 6531 | void |
| 6532 | Target_arm<big_endian>::relocate_for_relocatable( |
| 6533 | const Relocate_info<32, big_endian>* relinfo, |
| 6534 | unsigned int sh_type, |
| 6535 | const unsigned char* prelocs, |
| 6536 | size_t reloc_count, |
| 6537 | Output_section* output_section, |
| 6538 | off_t offset_in_output_section, |
| 6539 | const Relocatable_relocs* rr, |
| 6540 | unsigned char* view, |
| 6541 | Arm_address view_address, |
| 6542 | section_size_type view_size, |
| 6543 | unsigned char* reloc_view, |
| 6544 | section_size_type reloc_view_size) |
| 6545 | { |
| 6546 | gold_assert(sh_type == elfcpp::SHT_REL); |
| 6547 | |
| 6548 | gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>( |
| 6549 | relinfo, |
| 6550 | prelocs, |
| 6551 | reloc_count, |
| 6552 | output_section, |
| 6553 | offset_in_output_section, |
| 6554 | rr, |
| 6555 | view, |
| 6556 | view_address, |
| 6557 | view_size, |
| 6558 | reloc_view, |
| 6559 | reloc_view_size); |
| 6560 | } |
| 6561 | |
| 6562 | // Return the value to use for a dynamic symbol which requires special |
| 6563 | // treatment. This is how we support equality comparisons of function |
| 6564 | // pointers across shared library boundaries, as described in the |
| 6565 | // processor specific ABI supplement. |
| 6566 | |
| 6567 | template<bool big_endian> |
| 6568 | uint64_t |
| 6569 | Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const |
| 6570 | { |
| 6571 | gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset()); |
| 6572 | return this->plt_section()->address() + gsym->plt_offset(); |
| 6573 | } |
| 6574 | |
| 6575 | // Map platform-specific relocs to real relocs |
| 6576 | // |
| 6577 | template<bool big_endian> |
| 6578 | unsigned int |
| 6579 | Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type) |
| 6580 | { |
| 6581 | switch (r_type) |
| 6582 | { |
| 6583 | case elfcpp::R_ARM_TARGET1: |
| 6584 | // This is either R_ARM_ABS32 or R_ARM_REL32; |
| 6585 | return elfcpp::R_ARM_ABS32; |
| 6586 | |
| 6587 | case elfcpp::R_ARM_TARGET2: |
| 6588 | // This can be any reloc type but ususally is R_ARM_GOT_PREL |
| 6589 | return elfcpp::R_ARM_GOT_PREL; |
| 6590 | |
| 6591 | default: |
| 6592 | return r_type; |
| 6593 | } |
| 6594 | } |
| 6595 | |
| 6596 | // Whether if two EABI versions V1 and V2 are compatible. |
| 6597 | |
| 6598 | template<bool big_endian> |
| 6599 | bool |
| 6600 | Target_arm<big_endian>::are_eabi_versions_compatible( |
| 6601 | elfcpp::Elf_Word v1, |
| 6602 | elfcpp::Elf_Word v2) |
| 6603 | { |
| 6604 | // v4 and v5 are the same spec before and after it was released, |
| 6605 | // so allow mixing them. |
| 6606 | if ((v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5) |
| 6607 | || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4)) |
| 6608 | return true; |
| 6609 | |
| 6610 | return v1 == v2; |
| 6611 | } |
| 6612 | |
| 6613 | // Combine FLAGS from an input object called NAME and the processor-specific |
| 6614 | // flags in the ELF header of the output. Much of this is adapted from the |
| 6615 | // processor-specific flags merging code in elf32_arm_merge_private_bfd_data |
| 6616 | // in bfd/elf32-arm.c. |
| 6617 | |
| 6618 | template<bool big_endian> |
| 6619 | void |
| 6620 | Target_arm<big_endian>::merge_processor_specific_flags( |
| 6621 | const std::string& name, |
| 6622 | elfcpp::Elf_Word flags) |
| 6623 | { |
| 6624 | if (this->are_processor_specific_flags_set()) |
| 6625 | { |
| 6626 | elfcpp::Elf_Word out_flags = this->processor_specific_flags(); |
| 6627 | |
| 6628 | // Nothing to merge if flags equal to those in output. |
| 6629 | if (flags == out_flags) |
| 6630 | return; |
| 6631 | |
| 6632 | // Complain about various flag mismatches. |
| 6633 | elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags); |
| 6634 | elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags); |
| 6635 | if (!this->are_eabi_versions_compatible(version1, version2)) |
| 6636 | gold_error(_("Source object %s has EABI version %d but output has " |
| 6637 | "EABI version %d."), |
| 6638 | name.c_str(), |
| 6639 | (flags & elfcpp::EF_ARM_EABIMASK) >> 24, |
| 6640 | (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24); |
| 6641 | } |
| 6642 | else |
| 6643 | { |
| 6644 | // If the input is the default architecture and had the default |
| 6645 | // flags then do not bother setting the flags for the output |
| 6646 | // architecture, instead allow future merges to do this. If no |
| 6647 | // future merges ever set these flags then they will retain their |
| 6648 | // uninitialised values, which surprise surprise, correspond |
| 6649 | // to the default values. |
| 6650 | if (flags == 0) |
| 6651 | return; |
| 6652 | |
| 6653 | // This is the first time, just copy the flags. |
| 6654 | // We only copy the EABI version for now. |
| 6655 | this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK); |
| 6656 | } |
| 6657 | } |
| 6658 | |
| 6659 | // Adjust ELF file header. |
| 6660 | template<bool big_endian> |
| 6661 | void |
| 6662 | Target_arm<big_endian>::do_adjust_elf_header( |
| 6663 | unsigned char* view, |
| 6664 | int len) const |
| 6665 | { |
| 6666 | gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size); |
| 6667 | |
| 6668 | elfcpp::Ehdr<32, big_endian> ehdr(view); |
| 6669 | unsigned char e_ident[elfcpp::EI_NIDENT]; |
| 6670 | memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT); |
| 6671 | |
| 6672 | if (elfcpp::arm_eabi_version(this->processor_specific_flags()) |
| 6673 | == elfcpp::EF_ARM_EABI_UNKNOWN) |
| 6674 | e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM; |
| 6675 | else |
| 6676 | e_ident[elfcpp::EI_OSABI] = 0; |
| 6677 | e_ident[elfcpp::EI_ABIVERSION] = 0; |
| 6678 | |
| 6679 | // FIXME: Do EF_ARM_BE8 adjustment. |
| 6680 | |
| 6681 | elfcpp::Ehdr_write<32, big_endian> oehdr(view); |
| 6682 | oehdr.put_e_ident(e_ident); |
| 6683 | } |
| 6684 | |
| 6685 | // do_make_elf_object to override the same function in the base class. |
| 6686 | // We need to use a target-specific sub-class of Sized_relobj<32, big_endian> |
| 6687 | // to store ARM specific information. Hence we need to have our own |
| 6688 | // ELF object creation. |
| 6689 | |
| 6690 | template<bool big_endian> |
| 6691 | Object* |
| 6692 | Target_arm<big_endian>::do_make_elf_object( |
| 6693 | const std::string& name, |
| 6694 | Input_file* input_file, |
| 6695 | off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr) |
| 6696 | { |
| 6697 | int et = ehdr.get_e_type(); |
| 6698 | if (et == elfcpp::ET_REL) |
| 6699 | { |
| 6700 | Arm_relobj<big_endian>* obj = |
| 6701 | new Arm_relobj<big_endian>(name, input_file, offset, ehdr); |
| 6702 | obj->setup(); |
| 6703 | return obj; |
| 6704 | } |
| 6705 | else if (et == elfcpp::ET_DYN) |
| 6706 | { |
| 6707 | Sized_dynobj<32, big_endian>* obj = |
| 6708 | new Arm_dynobj<big_endian>(name, input_file, offset, ehdr); |
| 6709 | obj->setup(); |
| 6710 | return obj; |
| 6711 | } |
| 6712 | else |
| 6713 | { |
| 6714 | gold_error(_("%s: unsupported ELF file type %d"), |
| 6715 | name.c_str(), et); |
| 6716 | return NULL; |
| 6717 | } |
| 6718 | } |
| 6719 | |
| 6720 | // Read the architecture from the Tag_also_compatible_with attribute, if any. |
| 6721 | // Returns -1 if no architecture could be read. |
| 6722 | // This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c. |
| 6723 | |
| 6724 | template<bool big_endian> |
| 6725 | int |
| 6726 | Target_arm<big_endian>::get_secondary_compatible_arch( |
| 6727 | const Attributes_section_data* pasd) |
| 6728 | { |
| 6729 | const Object_attribute *known_attributes = |
| 6730 | pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC); |
| 6731 | |
| 6732 | // Note: the tag and its argument below are uleb128 values, though |
| 6733 | // currently-defined values fit in one byte for each. |
| 6734 | const std::string& sv = |
| 6735 | known_attributes[elfcpp::Tag_also_compatible_with].string_value(); |
| 6736 | if (sv.size() == 2 |
| 6737 | && sv.data()[0] == elfcpp::Tag_CPU_arch |
| 6738 | && (sv.data()[1] & 128) != 128) |
| 6739 | return sv.data()[1]; |
| 6740 | |
| 6741 | // This tag is "safely ignorable", so don't complain if it looks funny. |
| 6742 | return -1; |
| 6743 | } |
| 6744 | |
| 6745 | // Set, or unset, the architecture of the Tag_also_compatible_with attribute. |
| 6746 | // The tag is removed if ARCH is -1. |
| 6747 | // This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c. |
| 6748 | |
| 6749 | template<bool big_endian> |
| 6750 | void |
| 6751 | Target_arm<big_endian>::set_secondary_compatible_arch( |
| 6752 | Attributes_section_data* pasd, |
| 6753 | int arch) |
| 6754 | { |
| 6755 | Object_attribute *known_attributes = |
| 6756 | pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC); |
| 6757 | |
| 6758 | if (arch == -1) |
| 6759 | { |
| 6760 | known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(""); |
| 6761 | return; |
| 6762 | } |
| 6763 | |
| 6764 | // Note: the tag and its argument below are uleb128 values, though |
| 6765 | // currently-defined values fit in one byte for each. |
| 6766 | char sv[3]; |
| 6767 | sv[0] = elfcpp::Tag_CPU_arch; |
| 6768 | gold_assert(arch != 0); |
| 6769 | sv[1] = arch; |
| 6770 | sv[2] = '\0'; |
| 6771 | |
| 6772 | known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv); |
| 6773 | } |
| 6774 | |
| 6775 | // Combine two values for Tag_CPU_arch, taking secondary compatibility tags |
| 6776 | // into account. |
| 6777 | // This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c. |
| 6778 | |
| 6779 | template<bool big_endian> |
| 6780 | int |
| 6781 | Target_arm<big_endian>::tag_cpu_arch_combine( |
| 6782 | const char* name, |
| 6783 | int oldtag, |
| 6784 | int* secondary_compat_out, |
| 6785 | int newtag, |
| 6786 | int secondary_compat) |
| 6787 | { |
| 6788 | #define T(X) elfcpp::TAG_CPU_ARCH_##X |
| 6789 | static const int v6t2[] = |
| 6790 | { |
| 6791 | T(V6T2), // PRE_V4. |
| 6792 | T(V6T2), // V4. |
| 6793 | T(V6T2), // V4T. |
| 6794 | T(V6T2), // V5T. |
| 6795 | T(V6T2), // V5TE. |
| 6796 | T(V6T2), // V5TEJ. |
| 6797 | T(V6T2), // V6. |
| 6798 | T(V7), // V6KZ. |
| 6799 | T(V6T2) // V6T2. |
| 6800 | }; |
| 6801 | static const int v6k[] = |
| 6802 | { |
| 6803 | T(V6K), // PRE_V4. |
| 6804 | T(V6K), // V4. |
| 6805 | T(V6K), // V4T. |
| 6806 | T(V6K), // V5T. |
| 6807 | T(V6K), // V5TE. |
| 6808 | T(V6K), // V5TEJ. |
| 6809 | T(V6K), // V6. |
| 6810 | T(V6KZ), // V6KZ. |
| 6811 | T(V7), // V6T2. |
| 6812 | T(V6K) // V6K. |
| 6813 | }; |
| 6814 | static const int v7[] = |
| 6815 | { |
| 6816 | T(V7), // PRE_V4. |
| 6817 | T(V7), // V4. |
| 6818 | T(V7), // V4T. |
| 6819 | T(V7), // V5T. |
| 6820 | T(V7), // V5TE. |
| 6821 | T(V7), // V5TEJ. |
| 6822 | T(V7), // V6. |
| 6823 | T(V7), // V6KZ. |
| 6824 | T(V7), // V6T2. |
| 6825 | T(V7), // V6K. |
| 6826 | T(V7) // V7. |
| 6827 | }; |
| 6828 | static const int v6_m[] = |
| 6829 | { |
| 6830 | -1, // PRE_V4. |
| 6831 | -1, // V4. |
| 6832 | T(V6K), // V4T. |
| 6833 | T(V6K), // V5T. |
| 6834 | T(V6K), // V5TE. |
| 6835 | T(V6K), // V5TEJ. |
| 6836 | T(V6K), // V6. |
| 6837 | T(V6KZ), // V6KZ. |
| 6838 | T(V7), // V6T2. |
| 6839 | T(V6K), // V6K. |
| 6840 | T(V7), // V7. |
| 6841 | T(V6_M) // V6_M. |
| 6842 | }; |
| 6843 | static const int v6s_m[] = |
| 6844 | { |
| 6845 | -1, // PRE_V4. |
| 6846 | -1, // V4. |
| 6847 | T(V6K), // V4T. |
| 6848 | T(V6K), // V5T. |
| 6849 | T(V6K), // V5TE. |
| 6850 | T(V6K), // V5TEJ. |
| 6851 | T(V6K), // V6. |
| 6852 | T(V6KZ), // V6KZ. |
| 6853 | T(V7), // V6T2. |
| 6854 | T(V6K), // V6K. |
| 6855 | T(V7), // V7. |
| 6856 | T(V6S_M), // V6_M. |
| 6857 | T(V6S_M) // V6S_M. |
| 6858 | }; |
| 6859 | static const int v7e_m[] = |
| 6860 | { |
| 6861 | -1, // PRE_V4. |
| 6862 | -1, // V4. |
| 6863 | T(V7E_M), // V4T. |
| 6864 | T(V7E_M), // V5T. |
| 6865 | T(V7E_M), // V5TE. |
| 6866 | T(V7E_M), // V5TEJ. |
| 6867 | T(V7E_M), // V6. |
| 6868 | T(V7E_M), // V6KZ. |
| 6869 | T(V7E_M), // V6T2. |
| 6870 | T(V7E_M), // V6K. |
| 6871 | T(V7E_M), // V7. |
| 6872 | T(V7E_M), // V6_M. |
| 6873 | T(V7E_M), // V6S_M. |
| 6874 | T(V7E_M) // V7E_M. |
| 6875 | }; |
| 6876 | static const int v4t_plus_v6_m[] = |
| 6877 | { |
| 6878 | -1, // PRE_V4. |
| 6879 | -1, // V4. |
| 6880 | T(V4T), // V4T. |
| 6881 | T(V5T), // V5T. |
| 6882 | T(V5TE), // V5TE. |
| 6883 | T(V5TEJ), // V5TEJ. |
| 6884 | T(V6), // V6. |
| 6885 | T(V6KZ), // V6KZ. |
| 6886 | T(V6T2), // V6T2. |
| 6887 | T(V6K), // V6K. |
| 6888 | T(V7), // V7. |
| 6889 | T(V6_M), // V6_M. |
| 6890 | T(V6S_M), // V6S_M. |
| 6891 | T(V7E_M), // V7E_M. |
| 6892 | T(V4T_PLUS_V6_M) // V4T plus V6_M. |
| 6893 | }; |
| 6894 | static const int *comb[] = |
| 6895 | { |
| 6896 | v6t2, |
| 6897 | v6k, |
| 6898 | v7, |
| 6899 | v6_m, |
| 6900 | v6s_m, |
| 6901 | v7e_m, |
| 6902 | // Pseudo-architecture. |
| 6903 | v4t_plus_v6_m |
| 6904 | }; |
| 6905 | |
| 6906 | // Check we've not got a higher architecture than we know about. |
| 6907 | |
| 6908 | if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH) |
| 6909 | { |
| 6910 | gold_error(_("%s: unknown CPU architecture"), name); |
| 6911 | return -1; |
| 6912 | } |
| 6913 | |
| 6914 | // Override old tag if we have a Tag_also_compatible_with on the output. |
| 6915 | |
| 6916 | if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T)) |
| 6917 | || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M))) |
| 6918 | oldtag = T(V4T_PLUS_V6_M); |
| 6919 | |
| 6920 | // And override the new tag if we have a Tag_also_compatible_with on the |
| 6921 | // input. |
| 6922 | |
| 6923 | if ((newtag == T(V6_M) && secondary_compat == T(V4T)) |
| 6924 | || (newtag == T(V4T) && secondary_compat == T(V6_M))) |
| 6925 | newtag = T(V4T_PLUS_V6_M); |
| 6926 | |
| 6927 | // Architectures before V6KZ add features monotonically. |
| 6928 | int tagh = std::max(oldtag, newtag); |
| 6929 | if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ) |
| 6930 | return tagh; |
| 6931 | |
| 6932 | int tagl = std::min(oldtag, newtag); |
| 6933 | int result = comb[tagh - T(V6T2)][tagl]; |
| 6934 | |
| 6935 | // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M) |
| 6936 | // as the canonical version. |
| 6937 | if (result == T(V4T_PLUS_V6_M)) |
| 6938 | { |
| 6939 | result = T(V4T); |
| 6940 | *secondary_compat_out = T(V6_M); |
| 6941 | } |
| 6942 | else |
| 6943 | *secondary_compat_out = -1; |
| 6944 | |
| 6945 | if (result == -1) |
| 6946 | { |
| 6947 | gold_error(_("%s: conflicting CPU architectures %d/%d"), |
| 6948 | name, oldtag, newtag); |
| 6949 | return -1; |
| 6950 | } |
| 6951 | |
| 6952 | return result; |
| 6953 | #undef T |
| 6954 | } |
| 6955 | |
| 6956 | // Helper to print AEABI enum tag value. |
| 6957 | |
| 6958 | template<bool big_endian> |
| 6959 | std::string |
| 6960 | Target_arm<big_endian>::aeabi_enum_name(unsigned int value) |
| 6961 | { |
| 6962 | static const char *aeabi_enum_names[] = |
| 6963 | { "", "variable-size", "32-bit", "" }; |
| 6964 | const size_t aeabi_enum_names_size = |
| 6965 | sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]); |
| 6966 | |
| 6967 | if (value < aeabi_enum_names_size) |
| 6968 | return std::string(aeabi_enum_names[value]); |
| 6969 | else |
| 6970 | { |
| 6971 | char buffer[100]; |
| 6972 | sprintf(buffer, "<unknown value %u>", value); |
| 6973 | return std::string(buffer); |
| 6974 | } |
| 6975 | } |
| 6976 | |
| 6977 | // Return the string value to store in TAG_CPU_name. |
| 6978 | |
| 6979 | template<bool big_endian> |
| 6980 | std::string |
| 6981 | Target_arm<big_endian>::tag_cpu_name_value(unsigned int value) |
| 6982 | { |
| 6983 | static const char *name_table[] = { |
| 6984 | // These aren't real CPU names, but we can't guess |
| 6985 | // that from the architecture version alone. |
| 6986 | "Pre v4", |
| 6987 | "ARM v4", |
| 6988 | "ARM v4T", |
| 6989 | "ARM v5T", |
| 6990 | "ARM v5TE", |
| 6991 | "ARM v5TEJ", |
| 6992 | "ARM v6", |
| 6993 | "ARM v6KZ", |
| 6994 | "ARM v6T2", |
| 6995 | "ARM v6K", |
| 6996 | "ARM v7", |
| 6997 | "ARM v6-M", |
| 6998 | "ARM v6S-M", |
| 6999 | "ARM v7E-M" |
| 7000 | }; |
| 7001 | const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]); |
| 7002 | |
| 7003 | if (value < name_table_size) |
| 7004 | return std::string(name_table[value]); |
| 7005 | else |
| 7006 | { |
| 7007 | char buffer[100]; |
| 7008 | sprintf(buffer, "<unknown CPU value %u>", value); |
| 7009 | return std::string(buffer); |
| 7010 | } |
| 7011 | } |
| 7012 | |
| 7013 | // Merge object attributes from input file called NAME with those of the |
| 7014 | // output. The input object attributes are in the object pointed by PASD. |
| 7015 | |
| 7016 | template<bool big_endian> |
| 7017 | void |
| 7018 | Target_arm<big_endian>::merge_object_attributes( |
| 7019 | const char* name, |
| 7020 | const Attributes_section_data* pasd) |
| 7021 | { |
| 7022 | // Return if there is no attributes section data. |
| 7023 | if (pasd == NULL) |
| 7024 | return; |
| 7025 | |
| 7026 | // If output has no object attributes, just copy. |
| 7027 | if (this->attributes_section_data_ == NULL) |
| 7028 | { |
| 7029 | this->attributes_section_data_ = new Attributes_section_data(*pasd); |
| 7030 | return; |
| 7031 | } |
| 7032 | |
| 7033 | const int vendor = Object_attribute::OBJ_ATTR_PROC; |
| 7034 | const Object_attribute* in_attr = pasd->known_attributes(vendor); |
| 7035 | Object_attribute* out_attr = |
| 7036 | this->attributes_section_data_->known_attributes(vendor); |
| 7037 | |
| 7038 | // This needs to happen before Tag_ABI_FP_number_model is merged. */ |
| 7039 | if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value() |
| 7040 | != out_attr[elfcpp::Tag_ABI_VFP_args].int_value()) |
| 7041 | { |
| 7042 | // Ignore mismatches if the object doesn't use floating point. */ |
| 7043 | if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0) |
| 7044 | out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value( |
| 7045 | in_attr[elfcpp::Tag_ABI_VFP_args].int_value()); |
| 7046 | else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0) |
| 7047 | gold_error(_("%s uses VFP register arguments, output does not"), |
| 7048 | name); |
| 7049 | } |
| 7050 | |
| 7051 | for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i) |
| 7052 | { |
| 7053 | // Merge this attribute with existing attributes. |
| 7054 | switch (i) |
| 7055 | { |
| 7056 | case elfcpp::Tag_CPU_raw_name: |
| 7057 | case elfcpp::Tag_CPU_name: |
| 7058 | // These are merged after Tag_CPU_arch. |
| 7059 | break; |
| 7060 | |
| 7061 | case elfcpp::Tag_ABI_optimization_goals: |
| 7062 | case elfcpp::Tag_ABI_FP_optimization_goals: |
| 7063 | // Use the first value seen. |
| 7064 | break; |
| 7065 | |
| 7066 | case elfcpp::Tag_CPU_arch: |
| 7067 | { |
| 7068 | unsigned int saved_out_attr = out_attr->int_value(); |
| 7069 | // Merge Tag_CPU_arch and Tag_also_compatible_with. |
| 7070 | int secondary_compat = |
| 7071 | this->get_secondary_compatible_arch(pasd); |
| 7072 | int secondary_compat_out = |
| 7073 | this->get_secondary_compatible_arch( |
| 7074 | this->attributes_section_data_); |
| 7075 | out_attr[i].set_int_value( |
| 7076 | tag_cpu_arch_combine(name, out_attr[i].int_value(), |
| 7077 | &secondary_compat_out, |
| 7078 | in_attr[i].int_value(), |
| 7079 | secondary_compat)); |
| 7080 | this->set_secondary_compatible_arch(this->attributes_section_data_, |
| 7081 | secondary_compat_out); |
| 7082 | |
| 7083 | // Merge Tag_CPU_name and Tag_CPU_raw_name. |
| 7084 | if (out_attr[i].int_value() == saved_out_attr) |
| 7085 | ; // Leave the names alone. |
| 7086 | else if (out_attr[i].int_value() == in_attr[i].int_value()) |
| 7087 | { |
| 7088 | // The output architecture has been changed to match the |
| 7089 | // input architecture. Use the input names. |
| 7090 | out_attr[elfcpp::Tag_CPU_name].set_string_value( |
| 7091 | in_attr[elfcpp::Tag_CPU_name].string_value()); |
| 7092 | out_attr[elfcpp::Tag_CPU_raw_name].set_string_value( |
| 7093 | in_attr[elfcpp::Tag_CPU_raw_name].string_value()); |
| 7094 | } |
| 7095 | else |
| 7096 | { |
| 7097 | out_attr[elfcpp::Tag_CPU_name].set_string_value(""); |
| 7098 | out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(""); |
| 7099 | } |
| 7100 | |
| 7101 | // If we still don't have a value for Tag_CPU_name, |
| 7102 | // make one up now. Tag_CPU_raw_name remains blank. |
| 7103 | if (out_attr[elfcpp::Tag_CPU_name].string_value() == "") |
| 7104 | { |
| 7105 | const std::string cpu_name = |
| 7106 | this->tag_cpu_name_value(out_attr[i].int_value()); |
| 7107 | // FIXME: If we see an unknown CPU, this will be set |
| 7108 | // to "<unknown CPU n>", where n is the attribute value. |
| 7109 | // This is different from BFD, which leaves the name alone. |
| 7110 | out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name); |
| 7111 | } |
| 7112 | } |
| 7113 | break; |
| 7114 | |
| 7115 | case elfcpp::Tag_ARM_ISA_use: |
| 7116 | case elfcpp::Tag_THUMB_ISA_use: |
| 7117 | case elfcpp::Tag_WMMX_arch: |
| 7118 | case elfcpp::Tag_Advanced_SIMD_arch: |
| 7119 | // ??? Do Advanced_SIMD (NEON) and WMMX conflict? |
| 7120 | case elfcpp::Tag_ABI_FP_rounding: |
| 7121 | case elfcpp::Tag_ABI_FP_exceptions: |
| 7122 | case elfcpp::Tag_ABI_FP_user_exceptions: |
| 7123 | case elfcpp::Tag_ABI_FP_number_model: |
| 7124 | case elfcpp::Tag_VFP_HP_extension: |
| 7125 | case elfcpp::Tag_CPU_unaligned_access: |
| 7126 | case elfcpp::Tag_T2EE_use: |
| 7127 | case elfcpp::Tag_Virtualization_use: |
| 7128 | case elfcpp::Tag_MPextension_use: |
| 7129 | // Use the largest value specified. |
| 7130 | if (in_attr[i].int_value() > out_attr[i].int_value()) |
| 7131 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7132 | break; |
| 7133 | |
| 7134 | case elfcpp::Tag_ABI_align8_preserved: |
| 7135 | case elfcpp::Tag_ABI_PCS_RO_data: |
| 7136 | // Use the smallest value specified. |
| 7137 | if (in_attr[i].int_value() < out_attr[i].int_value()) |
| 7138 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7139 | break; |
| 7140 | |
| 7141 | case elfcpp::Tag_ABI_align8_needed: |
| 7142 | if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0) |
| 7143 | && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0 |
| 7144 | || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value() |
| 7145 | == 0))) |
| 7146 | { |
| 7147 | // This error message should be enabled once all non-conformant |
| 7148 | // binaries in the toolchain have had the attributes set |
| 7149 | // properly. |
| 7150 | // gold_error(_("output 8-byte data alignment conflicts with %s"), |
| 7151 | // name); |
| 7152 | } |
| 7153 | // Fall through. |
| 7154 | case elfcpp::Tag_ABI_FP_denormal: |
| 7155 | case elfcpp::Tag_ABI_PCS_GOT_use: |
| 7156 | { |
| 7157 | // These tags have 0 = don't care, 1 = strong requirement, |
| 7158 | // 2 = weak requirement. |
| 7159 | static const int order_021[3] = {0, 2, 1}; |
| 7160 | |
| 7161 | // Use the "greatest" from the sequence 0, 2, 1, or the largest |
| 7162 | // value if greater than 2 (for future-proofing). |
| 7163 | if ((in_attr[i].int_value() > 2 |
| 7164 | && in_attr[i].int_value() > out_attr[i].int_value()) |
| 7165 | || (in_attr[i].int_value() <= 2 |
| 7166 | && out_attr[i].int_value() <= 2 |
| 7167 | && (order_021[in_attr[i].int_value()] |
| 7168 | > order_021[out_attr[i].int_value()]))) |
| 7169 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7170 | } |
| 7171 | break; |
| 7172 | |
| 7173 | case elfcpp::Tag_CPU_arch_profile: |
| 7174 | if (out_attr[i].int_value() != in_attr[i].int_value()) |
| 7175 | { |
| 7176 | // 0 will merge with anything. |
| 7177 | // 'A' and 'S' merge to 'A'. |
| 7178 | // 'R' and 'S' merge to 'R'. |
| 7179 | // 'M' and 'A|R|S' is an error. |
| 7180 | if (out_attr[i].int_value() == 0 |
| 7181 | || (out_attr[i].int_value() == 'S' |
| 7182 | && (in_attr[i].int_value() == 'A' |
| 7183 | || in_attr[i].int_value() == 'R'))) |
| 7184 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7185 | else if (in_attr[i].int_value() == 0 |
| 7186 | || (in_attr[i].int_value() == 'S' |
| 7187 | && (out_attr[i].int_value() == 'A' |
| 7188 | || out_attr[i].int_value() == 'R'))) |
| 7189 | ; // Do nothing. |
| 7190 | else |
| 7191 | { |
| 7192 | gold_error |
| 7193 | (_("conflicting architecture profiles %c/%c"), |
| 7194 | in_attr[i].int_value() ? in_attr[i].int_value() : '0', |
| 7195 | out_attr[i].int_value() ? out_attr[i].int_value() : '0'); |
| 7196 | } |
| 7197 | } |
| 7198 | break; |
| 7199 | case elfcpp::Tag_VFP_arch: |
| 7200 | { |
| 7201 | static const struct |
| 7202 | { |
| 7203 | int ver; |
| 7204 | int regs; |
| 7205 | } vfp_versions[7] = |
| 7206 | { |
| 7207 | {0, 0}, |
| 7208 | {1, 16}, |
| 7209 | {2, 16}, |
| 7210 | {3, 32}, |
| 7211 | {3, 16}, |
| 7212 | {4, 32}, |
| 7213 | {4, 16} |
| 7214 | }; |
| 7215 | |
| 7216 | // Values greater than 6 aren't defined, so just pick the |
| 7217 | // biggest. |
| 7218 | if (in_attr[i].int_value() > 6 |
| 7219 | && in_attr[i].int_value() > out_attr[i].int_value()) |
| 7220 | { |
| 7221 | *out_attr = *in_attr; |
| 7222 | break; |
| 7223 | } |
| 7224 | // The output uses the superset of input features |
| 7225 | // (ISA version) and registers. |
| 7226 | int ver = std::max(vfp_versions[in_attr[i].int_value()].ver, |
| 7227 | vfp_versions[out_attr[i].int_value()].ver); |
| 7228 | int regs = std::max(vfp_versions[in_attr[i].int_value()].regs, |
| 7229 | vfp_versions[out_attr[i].int_value()].regs); |
| 7230 | // This assumes all possible supersets are also a valid |
| 7231 | // options. |
| 7232 | int newval; |
| 7233 | for (newval = 6; newval > 0; newval--) |
| 7234 | { |
| 7235 | if (regs == vfp_versions[newval].regs |
| 7236 | && ver == vfp_versions[newval].ver) |
| 7237 | break; |
| 7238 | } |
| 7239 | out_attr[i].set_int_value(newval); |
| 7240 | } |
| 7241 | break; |
| 7242 | case elfcpp::Tag_PCS_config: |
| 7243 | if (out_attr[i].int_value() == 0) |
| 7244 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7245 | else if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0) |
| 7246 | { |
| 7247 | // It's sometimes ok to mix different configs, so this is only |
| 7248 | // a warning. |
| 7249 | gold_warning(_("%s: conflicting platform configuration"), name); |
| 7250 | } |
| 7251 | break; |
| 7252 | case elfcpp::Tag_ABI_PCS_R9_use: |
| 7253 | if (in_attr[i].int_value() != out_attr[i].int_value() |
| 7254 | && out_attr[i].int_value() != elfcpp::AEABI_R9_unused |
| 7255 | && in_attr[i].int_value() != elfcpp::AEABI_R9_unused) |
| 7256 | { |
| 7257 | gold_error(_("%s: conflicting use of R9"), name); |
| 7258 | } |
| 7259 | if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused) |
| 7260 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7261 | break; |
| 7262 | case elfcpp::Tag_ABI_PCS_RW_data: |
| 7263 | if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel |
| 7264 | && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value() |
| 7265 | != elfcpp::AEABI_R9_SB) |
| 7266 | && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value() |
| 7267 | != elfcpp::AEABI_R9_unused)) |
| 7268 | { |
| 7269 | gold_error(_("%s: SB relative addressing conflicts with use " |
| 7270 | "of R9"), |
| 7271 | name); |
| 7272 | } |
| 7273 | // Use the smallest value specified. |
| 7274 | if (in_attr[i].int_value() < out_attr[i].int_value()) |
| 7275 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7276 | break; |
| 7277 | case elfcpp::Tag_ABI_PCS_wchar_t: |
| 7278 | // FIXME: Make it possible to turn off this warning. |
| 7279 | if (out_attr[i].int_value() |
| 7280 | && in_attr[i].int_value() |
| 7281 | && out_attr[i].int_value() != in_attr[i].int_value()) |
| 7282 | { |
| 7283 | gold_warning(_("%s uses %u-byte wchar_t yet the output is to " |
| 7284 | "use %u-byte wchar_t; use of wchar_t values " |
| 7285 | "across objects may fail"), |
| 7286 | name, in_attr[i].int_value(), |
| 7287 | out_attr[i].int_value()); |
| 7288 | } |
| 7289 | else if (in_attr[i].int_value() && !out_attr[i].int_value()) |
| 7290 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7291 | break; |
| 7292 | case elfcpp::Tag_ABI_enum_size: |
| 7293 | if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused) |
| 7294 | { |
| 7295 | if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused |
| 7296 | || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide) |
| 7297 | { |
| 7298 | // The existing object is compatible with anything. |
| 7299 | // Use whatever requirements the new object has. |
| 7300 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7301 | } |
| 7302 | // FIXME: Make it possible to turn off this warning. |
| 7303 | else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide |
| 7304 | && out_attr[i].int_value() != in_attr[i].int_value()) |
| 7305 | { |
| 7306 | unsigned int in_value = in_attr[i].int_value(); |
| 7307 | unsigned int out_value = out_attr[i].int_value(); |
| 7308 | gold_warning(_("%s uses %s enums yet the output is to use " |
| 7309 | "%s enums; use of enum values across objects " |
| 7310 | "may fail"), |
| 7311 | name, |
| 7312 | this->aeabi_enum_name(in_value).c_str(), |
| 7313 | this->aeabi_enum_name(out_value).c_str()); |
| 7314 | } |
| 7315 | } |
| 7316 | break; |
| 7317 | case elfcpp::Tag_ABI_VFP_args: |
| 7318 | // Aready done. |
| 7319 | break; |
| 7320 | case elfcpp::Tag_ABI_WMMX_args: |
| 7321 | if (in_attr[i].int_value() != out_attr[i].int_value()) |
| 7322 | { |
| 7323 | gold_error(_("%s uses iWMMXt register arguments, output does " |
| 7324 | "not"), |
| 7325 | name); |
| 7326 | } |
| 7327 | break; |
| 7328 | case Object_attribute::Tag_compatibility: |
| 7329 | // Merged in target-independent code. |
| 7330 | break; |
| 7331 | case elfcpp::Tag_ABI_HardFP_use: |
| 7332 | // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP). |
| 7333 | if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2) |
| 7334 | || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1)) |
| 7335 | out_attr[i].set_int_value(3); |
| 7336 | else if (in_attr[i].int_value() > out_attr[i].int_value()) |
| 7337 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7338 | break; |
| 7339 | case elfcpp::Tag_ABI_FP_16bit_format: |
| 7340 | if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0) |
| 7341 | { |
| 7342 | if (in_attr[i].int_value() != out_attr[i].int_value()) |
| 7343 | gold_error(_("fp16 format mismatch between %s and output"), |
| 7344 | name); |
| 7345 | } |
| 7346 | if (in_attr[i].int_value() != 0) |
| 7347 | out_attr[i].set_int_value(in_attr[i].int_value()); |
| 7348 | break; |
| 7349 | |
| 7350 | case elfcpp::Tag_nodefaults: |
| 7351 | // This tag is set if it exists, but the value is unused (and is |
| 7352 | // typically zero). We don't actually need to do anything here - |
| 7353 | // the merge happens automatically when the type flags are merged |
| 7354 | // below. |
| 7355 | break; |
| 7356 | case elfcpp::Tag_also_compatible_with: |
| 7357 | // Already done in Tag_CPU_arch. |
| 7358 | break; |
| 7359 | case elfcpp::Tag_conformance: |
| 7360 | // Keep the attribute if it matches. Throw it away otherwise. |
| 7361 | // No attribute means no claim to conform. |
| 7362 | if (in_attr[i].string_value() != out_attr[i].string_value()) |
| 7363 | out_attr[i].set_string_value(""); |
| 7364 | break; |
| 7365 | |
| 7366 | default: |
| 7367 | { |
| 7368 | const char* err_object = NULL; |
| 7369 | |
| 7370 | // The "known_obj_attributes" table does contain some undefined |
| 7371 | // attributes. Ensure that there are unused. |
| 7372 | if (out_attr[i].int_value() != 0 |
| 7373 | || out_attr[i].string_value() != "") |
| 7374 | err_object = "output"; |
| 7375 | else if (in_attr[i].int_value() != 0 |
| 7376 | || in_attr[i].string_value() != "") |
| 7377 | err_object = name; |
| 7378 | |
| 7379 | if (err_object != NULL) |
| 7380 | { |
| 7381 | // Attribute numbers >=64 (mod 128) can be safely ignored. |
| 7382 | if ((i & 127) < 64) |
| 7383 | gold_error(_("%s: unknown mandatory EABI object attribute " |
| 7384 | "%d"), |
| 7385 | err_object, i); |
| 7386 | else |
| 7387 | gold_warning(_("%s: unknown EABI object attribute %d"), |
| 7388 | err_object, i); |
| 7389 | } |
| 7390 | |
| 7391 | // Only pass on attributes that match in both inputs. |
| 7392 | if (!in_attr[i].matches(out_attr[i])) |
| 7393 | { |
| 7394 | out_attr[i].set_int_value(0); |
| 7395 | out_attr[i].set_string_value(""); |
| 7396 | } |
| 7397 | } |
| 7398 | } |
| 7399 | |
| 7400 | // If out_attr was copied from in_attr then it won't have a type yet. |
| 7401 | if (in_attr[i].type() && !out_attr[i].type()) |
| 7402 | out_attr[i].set_type(in_attr[i].type()); |
| 7403 | } |
| 7404 | |
| 7405 | // Merge Tag_compatibility attributes and any common GNU ones. |
| 7406 | this->attributes_section_data_->merge(name, pasd); |
| 7407 | |
| 7408 | // Check for any attributes not known on ARM. |
| 7409 | typedef Vendor_object_attributes::Other_attributes Other_attributes; |
| 7410 | const Other_attributes* in_other_attributes = pasd->other_attributes(vendor); |
| 7411 | Other_attributes::const_iterator in_iter = in_other_attributes->begin(); |
| 7412 | Other_attributes* out_other_attributes = |
| 7413 | this->attributes_section_data_->other_attributes(vendor); |
| 7414 | Other_attributes::iterator out_iter = out_other_attributes->begin(); |
| 7415 | |
| 7416 | while (in_iter != in_other_attributes->end() |
| 7417 | || out_iter != out_other_attributes->end()) |
| 7418 | { |
| 7419 | const char* err_object = NULL; |
| 7420 | int err_tag = 0; |
| 7421 | |
| 7422 | // The tags for each list are in numerical order. |
| 7423 | // If the tags are equal, then merge. |
| 7424 | if (out_iter != out_other_attributes->end() |
| 7425 | && (in_iter == in_other_attributes->end() |
| 7426 | || in_iter->first > out_iter->first)) |
| 7427 | { |
| 7428 | // This attribute only exists in output. We can't merge, and we |
| 7429 | // don't know what the tag means, so delete it. |
| 7430 | err_object = "output"; |
| 7431 | err_tag = out_iter->first; |
| 7432 | int saved_tag = out_iter->first; |
| 7433 | delete out_iter->second; |
| 7434 | out_other_attributes->erase(out_iter); |
| 7435 | out_iter = out_other_attributes->upper_bound(saved_tag); |
| 7436 | } |
| 7437 | else if (in_iter != in_other_attributes->end() |
| 7438 | && (out_iter != out_other_attributes->end() |
| 7439 | || in_iter->first < out_iter->first)) |
| 7440 | { |
| 7441 | // This attribute only exists in input. We can't merge, and we |
| 7442 | // don't know what the tag means, so ignore it. |
| 7443 | err_object = name; |
| 7444 | err_tag = in_iter->first; |
| 7445 | ++in_iter; |
| 7446 | } |
| 7447 | else // The tags are equal. |
| 7448 | { |
| 7449 | // As present, all attributes in the list are unknown, and |
| 7450 | // therefore can't be merged meaningfully. |
| 7451 | err_object = "output"; |
| 7452 | err_tag = out_iter->first; |
| 7453 | |
| 7454 | // Only pass on attributes that match in both inputs. |
| 7455 | if (!in_iter->second->matches(*(out_iter->second))) |
| 7456 | { |
| 7457 | // No match. Delete the attribute. |
| 7458 | int saved_tag = out_iter->first; |
| 7459 | delete out_iter->second; |
| 7460 | out_other_attributes->erase(out_iter); |
| 7461 | out_iter = out_other_attributes->upper_bound(saved_tag); |
| 7462 | } |
| 7463 | else |
| 7464 | { |
| 7465 | // Matched. Keep the attribute and move to the next. |
| 7466 | ++out_iter; |
| 7467 | ++in_iter; |
| 7468 | } |
| 7469 | } |
| 7470 | |
| 7471 | if (err_object) |
| 7472 | { |
| 7473 | // Attribute numbers >=64 (mod 128) can be safely ignored. */ |
| 7474 | if ((err_tag & 127) < 64) |
| 7475 | { |
| 7476 | gold_error(_("%s: unknown mandatory EABI object attribute %d"), |
| 7477 | err_object, err_tag); |
| 7478 | } |
| 7479 | else |
| 7480 | { |
| 7481 | gold_warning(_("%s: unknown EABI object attribute %d"), |
| 7482 | err_object, err_tag); |
| 7483 | } |
| 7484 | } |
| 7485 | } |
| 7486 | } |
| 7487 | |
| 7488 | // Return whether a relocation type used the LSB to distinguish THUMB |
| 7489 | // addresses. |
| 7490 | template<bool big_endian> |
| 7491 | bool |
| 7492 | Target_arm<big_endian>::reloc_uses_thumb_bit(unsigned int r_type) |
| 7493 | { |
| 7494 | switch (r_type) |
| 7495 | { |
| 7496 | case elfcpp::R_ARM_PC24: |
| 7497 | case elfcpp::R_ARM_ABS32: |
| 7498 | case elfcpp::R_ARM_REL32: |
| 7499 | case elfcpp::R_ARM_SBREL32: |
| 7500 | case elfcpp::R_ARM_THM_CALL: |
| 7501 | case elfcpp::R_ARM_GLOB_DAT: |
| 7502 | case elfcpp::R_ARM_JUMP_SLOT: |
| 7503 | case elfcpp::R_ARM_GOTOFF32: |
| 7504 | case elfcpp::R_ARM_PLT32: |
| 7505 | case elfcpp::R_ARM_CALL: |
| 7506 | case elfcpp::R_ARM_JUMP24: |
| 7507 | case elfcpp::R_ARM_THM_JUMP24: |
| 7508 | case elfcpp::R_ARM_SBREL31: |
| 7509 | case elfcpp::R_ARM_PREL31: |
| 7510 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 7511 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 7512 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 7513 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 7514 | case elfcpp::R_ARM_THM_JUMP19: |
| 7515 | case elfcpp::R_ARM_THM_ALU_PREL_11_0: |
| 7516 | case elfcpp::R_ARM_ALU_PC_G0_NC: |
| 7517 | case elfcpp::R_ARM_ALU_PC_G0: |
| 7518 | case elfcpp::R_ARM_ALU_PC_G1_NC: |
| 7519 | case elfcpp::R_ARM_ALU_PC_G1: |
| 7520 | case elfcpp::R_ARM_ALU_PC_G2: |
| 7521 | case elfcpp::R_ARM_ALU_SB_G0_NC: |
| 7522 | case elfcpp::R_ARM_ALU_SB_G0: |
| 7523 | case elfcpp::R_ARM_ALU_SB_G1_NC: |
| 7524 | case elfcpp::R_ARM_ALU_SB_G1: |
| 7525 | case elfcpp::R_ARM_ALU_SB_G2: |
| 7526 | case elfcpp::R_ARM_MOVW_BREL_NC: |
| 7527 | case elfcpp::R_ARM_MOVW_BREL: |
| 7528 | case elfcpp::R_ARM_THM_MOVW_BREL_NC: |
| 7529 | case elfcpp::R_ARM_THM_MOVW_BREL: |
| 7530 | return true; |
| 7531 | default: |
| 7532 | return false; |
| 7533 | } |
| 7534 | } |
| 7535 | |
| 7536 | // Stub-generation methods for Target_arm. |
| 7537 | |
| 7538 | // Make a new Arm_input_section object. |
| 7539 | |
| 7540 | template<bool big_endian> |
| 7541 | Arm_input_section<big_endian>* |
| 7542 | Target_arm<big_endian>::new_arm_input_section( |
| 7543 | Relobj* relobj, |
| 7544 | unsigned int shndx) |
| 7545 | { |
| 7546 | Input_section_specifier iss(relobj, shndx); |
| 7547 | |
| 7548 | Arm_input_section<big_endian>* arm_input_section = |
| 7549 | new Arm_input_section<big_endian>(relobj, shndx); |
| 7550 | arm_input_section->init(); |
| 7551 | |
| 7552 | // Register new Arm_input_section in map for look-up. |
| 7553 | std::pair<typename Arm_input_section_map::iterator, bool> ins = |
| 7554 | this->arm_input_section_map_.insert(std::make_pair(iss, arm_input_section)); |
| 7555 | |
| 7556 | // Make sure that it we have not created another Arm_input_section |
| 7557 | // for this input section already. |
| 7558 | gold_assert(ins.second); |
| 7559 | |
| 7560 | return arm_input_section; |
| 7561 | } |
| 7562 | |
| 7563 | // Find the Arm_input_section object corresponding to the SHNDX-th input |
| 7564 | // section of RELOBJ. |
| 7565 | |
| 7566 | template<bool big_endian> |
| 7567 | Arm_input_section<big_endian>* |
| 7568 | Target_arm<big_endian>::find_arm_input_section( |
| 7569 | Relobj* relobj, |
| 7570 | unsigned int shndx) const |
| 7571 | { |
| 7572 | Input_section_specifier iss(relobj, shndx); |
| 7573 | typename Arm_input_section_map::const_iterator p = |
| 7574 | this->arm_input_section_map_.find(iss); |
| 7575 | return (p != this->arm_input_section_map_.end()) ? p->second : NULL; |
| 7576 | } |
| 7577 | |
| 7578 | // Make a new stub table. |
| 7579 | |
| 7580 | template<bool big_endian> |
| 7581 | Stub_table<big_endian>* |
| 7582 | Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner) |
| 7583 | { |
| 7584 | Stub_table<big_endian>* stub_table = |
| 7585 | new Stub_table<big_endian>(owner); |
| 7586 | this->stub_tables_.push_back(stub_table); |
| 7587 | |
| 7588 | stub_table->set_address(owner->address() + owner->data_size()); |
| 7589 | stub_table->set_file_offset(owner->offset() + owner->data_size()); |
| 7590 | stub_table->finalize_data_size(); |
| 7591 | |
| 7592 | return stub_table; |
| 7593 | } |
| 7594 | |
| 7595 | // Scan a relocation for stub generation. |
| 7596 | |
| 7597 | template<bool big_endian> |
| 7598 | void |
| 7599 | Target_arm<big_endian>::scan_reloc_for_stub( |
| 7600 | const Relocate_info<32, big_endian>* relinfo, |
| 7601 | unsigned int r_type, |
| 7602 | const Sized_symbol<32>* gsym, |
| 7603 | unsigned int r_sym, |
| 7604 | const Symbol_value<32>* psymval, |
| 7605 | elfcpp::Elf_types<32>::Elf_Swxword addend, |
| 7606 | Arm_address address) |
| 7607 | { |
| 7608 | typedef typename Target_arm<big_endian>::Relocate Relocate; |
| 7609 | |
| 7610 | const Arm_relobj<big_endian>* arm_relobj = |
| 7611 | Arm_relobj<big_endian>::as_arm_relobj(relinfo->object); |
| 7612 | |
| 7613 | if (r_type == elfcpp::R_ARM_V4BX) |
| 7614 | { |
| 7615 | const uint32_t reg = (addend & 0xf); |
| 7616 | if (this->fix_v4bx() == 2 && reg < 0xf) |
| 7617 | { |
| 7618 | // Try looking up an existing stub from a stub table. |
| 7619 | Stub_table<big_endian>* stub_table = |
| 7620 | arm_relobj->stub_table(relinfo->data_shndx); |
| 7621 | gold_assert(stub_table != NULL); |
| 7622 | |
| 7623 | if (stub_table->find_arm_v4bx_stub(reg) == NULL) |
| 7624 | { |
| 7625 | // create a new stub and add it to stub table. |
| 7626 | Arm_v4bx_stub* stub = |
| 7627 | this->stub_factory().make_arm_v4bx_stub(reg); |
| 7628 | gold_assert(stub != NULL); |
| 7629 | stub_table->add_arm_v4bx_stub(stub); |
| 7630 | } |
| 7631 | } |
| 7632 | |
| 7633 | return; |
| 7634 | } |
| 7635 | |
| 7636 | bool target_is_thumb; |
| 7637 | Symbol_value<32> symval; |
| 7638 | if (gsym != NULL) |
| 7639 | { |
| 7640 | // This is a global symbol. Determine if we use PLT and if the |
| 7641 | // final target is THUMB. |
| 7642 | if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type))) |
| 7643 | { |
| 7644 | // This uses a PLT, change the symbol value. |
| 7645 | symval.set_output_value(this->plt_section()->address() |
| 7646 | + gsym->plt_offset()); |
| 7647 | psymval = &symval; |
| 7648 | target_is_thumb = false; |
| 7649 | } |
| 7650 | else if (gsym->is_undefined()) |
| 7651 | // There is no need to generate a stub symbol is undefined. |
| 7652 | return; |
| 7653 | else |
| 7654 | { |
| 7655 | target_is_thumb = |
| 7656 | ((gsym->type() == elfcpp::STT_ARM_TFUNC) |
| 7657 | || (gsym->type() == elfcpp::STT_FUNC |
| 7658 | && !gsym->is_undefined() |
| 7659 | && ((psymval->value(arm_relobj, 0) & 1) != 0))); |
| 7660 | } |
| 7661 | } |
| 7662 | else |
| 7663 | { |
| 7664 | // This is a local symbol. Determine if the final target is THUMB. |
| 7665 | target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym); |
| 7666 | } |
| 7667 | |
| 7668 | // Strip LSB if this points to a THUMB target. |
| 7669 | if (target_is_thumb |
| 7670 | && Target_arm<big_endian>::reloc_uses_thumb_bit(r_type) |
| 7671 | && ((psymval->value(arm_relobj, 0) & 1) != 0)) |
| 7672 | { |
| 7673 | Arm_address stripped_value = |
| 7674 | psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1); |
| 7675 | symval.set_output_value(stripped_value); |
| 7676 | psymval = &symval; |
| 7677 | } |
| 7678 | |
| 7679 | // Get the symbol value. |
| 7680 | Symbol_value<32>::Value value = psymval->value(arm_relobj, 0); |
| 7681 | |
| 7682 | // Owing to pipelining, the PC relative branches below actually skip |
| 7683 | // two instructions when the branch offset is 0. |
| 7684 | Arm_address destination; |
| 7685 | switch (r_type) |
| 7686 | { |
| 7687 | case elfcpp::R_ARM_CALL: |
| 7688 | case elfcpp::R_ARM_JUMP24: |
| 7689 | case elfcpp::R_ARM_PLT32: |
| 7690 | // ARM branches. |
| 7691 | destination = value + addend + 8; |
| 7692 | break; |
| 7693 | case elfcpp::R_ARM_THM_CALL: |
| 7694 | case elfcpp::R_ARM_THM_XPC22: |
| 7695 | case elfcpp::R_ARM_THM_JUMP24: |
| 7696 | case elfcpp::R_ARM_THM_JUMP19: |
| 7697 | // THUMB branches. |
| 7698 | destination = value + addend + 4; |
| 7699 | break; |
| 7700 | default: |
| 7701 | gold_unreachable(); |
| 7702 | } |
| 7703 | |
| 7704 | Reloc_stub* stub = NULL; |
| 7705 | Stub_type stub_type = |
| 7706 | Reloc_stub::stub_type_for_reloc(r_type, address, destination, |
| 7707 | target_is_thumb); |
| 7708 | if (stub_type != arm_stub_none) |
| 7709 | { |
| 7710 | // Try looking up an existing stub from a stub table. |
| 7711 | Stub_table<big_endian>* stub_table = |
| 7712 | arm_relobj->stub_table(relinfo->data_shndx); |
| 7713 | gold_assert(stub_table != NULL); |
| 7714 | |
| 7715 | // Locate stub by destination. |
| 7716 | Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend); |
| 7717 | |
| 7718 | // Create a stub if there is not one already |
| 7719 | stub = stub_table->find_reloc_stub(stub_key); |
| 7720 | if (stub == NULL) |
| 7721 | { |
| 7722 | // create a new stub and add it to stub table. |
| 7723 | stub = this->stub_factory().make_reloc_stub(stub_type); |
| 7724 | stub_table->add_reloc_stub(stub, stub_key); |
| 7725 | } |
| 7726 | |
| 7727 | // Record the destination address. |
| 7728 | stub->set_destination_address(destination |
| 7729 | | (target_is_thumb ? 1 : 0)); |
| 7730 | } |
| 7731 | |
| 7732 | // For Cortex-A8, we need to record a relocation at 4K page boundary. |
| 7733 | if (this->fix_cortex_a8_ |
| 7734 | && (r_type == elfcpp::R_ARM_THM_JUMP24 |
| 7735 | || r_type == elfcpp::R_ARM_THM_JUMP19 |
| 7736 | || r_type == elfcpp::R_ARM_THM_CALL |
| 7737 | || r_type == elfcpp::R_ARM_THM_XPC22) |
| 7738 | && (address & 0xfffU) == 0xffeU) |
| 7739 | { |
| 7740 | // Found a candidate. Note we haven't checked the destination is |
| 7741 | // within 4K here: if we do so (and don't create a record) we can't |
| 7742 | // tell that a branch should have been relocated when scanning later. |
| 7743 | this->cortex_a8_relocs_info_[address] = |
| 7744 | new Cortex_a8_reloc(stub, r_type, |
| 7745 | destination | (target_is_thumb ? 1 : 0)); |
| 7746 | } |
| 7747 | } |
| 7748 | |
| 7749 | // This function scans a relocation sections for stub generation. |
| 7750 | // The template parameter Relocate must be a class type which provides |
| 7751 | // a single function, relocate(), which implements the machine |
| 7752 | // specific part of a relocation. |
| 7753 | |
| 7754 | // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type: |
| 7755 | // SHT_REL or SHT_RELA. |
| 7756 | |
| 7757 | // PRELOCS points to the relocation data. RELOC_COUNT is the number |
| 7758 | // of relocs. OUTPUT_SECTION is the output section. |
| 7759 | // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be |
| 7760 | // mapped to output offsets. |
| 7761 | |
| 7762 | // VIEW is the section data, VIEW_ADDRESS is its memory address, and |
| 7763 | // VIEW_SIZE is the size. These refer to the input section, unless |
| 7764 | // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to |
| 7765 | // the output section. |
| 7766 | |
| 7767 | template<bool big_endian> |
| 7768 | template<int sh_type> |
| 7769 | void inline |
| 7770 | Target_arm<big_endian>::scan_reloc_section_for_stubs( |
| 7771 | const Relocate_info<32, big_endian>* relinfo, |
| 7772 | const unsigned char* prelocs, |
| 7773 | size_t reloc_count, |
| 7774 | Output_section* output_section, |
| 7775 | bool needs_special_offset_handling, |
| 7776 | const unsigned char* view, |
| 7777 | elfcpp::Elf_types<32>::Elf_Addr view_address, |
| 7778 | section_size_type) |
| 7779 | { |
| 7780 | typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype; |
| 7781 | const int reloc_size = |
| 7782 | Reloc_types<sh_type, 32, big_endian>::reloc_size; |
| 7783 | |
| 7784 | Arm_relobj<big_endian>* arm_object = |
| 7785 | Arm_relobj<big_endian>::as_arm_relobj(relinfo->object); |
| 7786 | unsigned int local_count = arm_object->local_symbol_count(); |
| 7787 | |
| 7788 | Comdat_behavior comdat_behavior = CB_UNDETERMINED; |
| 7789 | |
| 7790 | for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size) |
| 7791 | { |
| 7792 | Reltype reloc(prelocs); |
| 7793 | |
| 7794 | typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info(); |
| 7795 | unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info); |
| 7796 | unsigned int r_type = elfcpp::elf_r_type<32>(r_info); |
| 7797 | |
| 7798 | r_type = this->get_real_reloc_type(r_type); |
| 7799 | |
| 7800 | // Only a few relocation types need stubs. |
| 7801 | if ((r_type != elfcpp::R_ARM_CALL) |
| 7802 | && (r_type != elfcpp::R_ARM_JUMP24) |
| 7803 | && (r_type != elfcpp::R_ARM_PLT32) |
| 7804 | && (r_type != elfcpp::R_ARM_THM_CALL) |
| 7805 | && (r_type != elfcpp::R_ARM_THM_XPC22) |
| 7806 | && (r_type != elfcpp::R_ARM_THM_JUMP24) |
| 7807 | && (r_type != elfcpp::R_ARM_THM_JUMP19) |
| 7808 | && (r_type != elfcpp::R_ARM_V4BX)) |
| 7809 | continue; |
| 7810 | |
| 7811 | section_offset_type offset = |
| 7812 | convert_to_section_size_type(reloc.get_r_offset()); |
| 7813 | |
| 7814 | if (needs_special_offset_handling) |
| 7815 | { |
| 7816 | offset = output_section->output_offset(relinfo->object, |
| 7817 | relinfo->data_shndx, |
| 7818 | offset); |
| 7819 | if (offset == -1) |
| 7820 | continue; |
| 7821 | } |
| 7822 | |
| 7823 | if (r_type == elfcpp::R_ARM_V4BX) |
| 7824 | { |
| 7825 | // Get the BX instruction. |
| 7826 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 7827 | const Valtype* wv = reinterpret_cast<const Valtype*>(view + offset); |
| 7828 | elfcpp::Elf_types<32>::Elf_Swxword insn = |
| 7829 | elfcpp::Swap<32, big_endian>::readval(wv); |
| 7830 | this->scan_reloc_for_stub(relinfo, r_type, NULL, 0, NULL, |
| 7831 | insn, NULL); |
| 7832 | continue; |
| 7833 | } |
| 7834 | |
| 7835 | // Get the addend. |
| 7836 | Stub_addend_reader<sh_type, big_endian> stub_addend_reader; |
| 7837 | elfcpp::Elf_types<32>::Elf_Swxword addend = |
| 7838 | stub_addend_reader(r_type, view + offset, reloc); |
| 7839 | |
| 7840 | const Sized_symbol<32>* sym; |
| 7841 | |
| 7842 | Symbol_value<32> symval; |
| 7843 | const Symbol_value<32> *psymval; |
| 7844 | if (r_sym < local_count) |
| 7845 | { |
| 7846 | sym = NULL; |
| 7847 | psymval = arm_object->local_symbol(r_sym); |
| 7848 | |
| 7849 | // If the local symbol belongs to a section we are discarding, |
| 7850 | // and that section is a debug section, try to find the |
| 7851 | // corresponding kept section and map this symbol to its |
| 7852 | // counterpart in the kept section. The symbol must not |
| 7853 | // correspond to a section we are folding. |
| 7854 | bool is_ordinary; |
| 7855 | unsigned int shndx = psymval->input_shndx(&is_ordinary); |
| 7856 | if (is_ordinary |
| 7857 | && shndx != elfcpp::SHN_UNDEF |
| 7858 | && !arm_object->is_section_included(shndx) |
| 7859 | && !(relinfo->symtab->is_section_folded(arm_object, shndx))) |
| 7860 | { |
| 7861 | if (comdat_behavior == CB_UNDETERMINED) |
| 7862 | { |
| 7863 | std::string name = |
| 7864 | arm_object->section_name(relinfo->data_shndx); |
| 7865 | comdat_behavior = get_comdat_behavior(name.c_str()); |
| 7866 | } |
| 7867 | if (comdat_behavior == CB_PRETEND) |
| 7868 | { |
| 7869 | bool found; |
| 7870 | typename elfcpp::Elf_types<32>::Elf_Addr value = |
| 7871 | arm_object->map_to_kept_section(shndx, &found); |
| 7872 | if (found) |
| 7873 | symval.set_output_value(value + psymval->input_value()); |
| 7874 | else |
| 7875 | symval.set_output_value(0); |
| 7876 | } |
| 7877 | else |
| 7878 | { |
| 7879 | symval.set_output_value(0); |
| 7880 | } |
| 7881 | symval.set_no_output_symtab_entry(); |
| 7882 | psymval = &symval; |
| 7883 | } |
| 7884 | } |
| 7885 | else |
| 7886 | { |
| 7887 | const Symbol* gsym = arm_object->global_symbol(r_sym); |
| 7888 | gold_assert(gsym != NULL); |
| 7889 | if (gsym->is_forwarder()) |
| 7890 | gsym = relinfo->symtab->resolve_forwards(gsym); |
| 7891 | |
| 7892 | sym = static_cast<const Sized_symbol<32>*>(gsym); |
| 7893 | if (sym->has_symtab_index()) |
| 7894 | symval.set_output_symtab_index(sym->symtab_index()); |
| 7895 | else |
| 7896 | symval.set_no_output_symtab_entry(); |
| 7897 | |
| 7898 | // We need to compute the would-be final value of this global |
| 7899 | // symbol. |
| 7900 | const Symbol_table* symtab = relinfo->symtab; |
| 7901 | const Sized_symbol<32>* sized_symbol = |
| 7902 | symtab->get_sized_symbol<32>(gsym); |
| 7903 | Symbol_table::Compute_final_value_status status; |
| 7904 | Arm_address value = |
| 7905 | symtab->compute_final_value<32>(sized_symbol, &status); |
| 7906 | |
| 7907 | // Skip this if the symbol has not output section. |
| 7908 | if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION) |
| 7909 | continue; |
| 7910 | |
| 7911 | symval.set_output_value(value); |
| 7912 | psymval = &symval; |
| 7913 | } |
| 7914 | |
| 7915 | // If symbol is a section symbol, we don't know the actual type of |
| 7916 | // destination. Give up. |
| 7917 | if (psymval->is_section_symbol()) |
| 7918 | continue; |
| 7919 | |
| 7920 | this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval, |
| 7921 | addend, view_address + offset); |
| 7922 | } |
| 7923 | } |
| 7924 | |
| 7925 | // Scan an input section for stub generation. |
| 7926 | |
| 7927 | template<bool big_endian> |
| 7928 | void |
| 7929 | Target_arm<big_endian>::scan_section_for_stubs( |
| 7930 | const Relocate_info<32, big_endian>* relinfo, |
| 7931 | unsigned int sh_type, |
| 7932 | const unsigned char* prelocs, |
| 7933 | size_t reloc_count, |
| 7934 | Output_section* output_section, |
| 7935 | bool needs_special_offset_handling, |
| 7936 | const unsigned char* view, |
| 7937 | Arm_address view_address, |
| 7938 | section_size_type view_size) |
| 7939 | { |
| 7940 | if (sh_type == elfcpp::SHT_REL) |
| 7941 | this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>( |
| 7942 | relinfo, |
| 7943 | prelocs, |
| 7944 | reloc_count, |
| 7945 | output_section, |
| 7946 | needs_special_offset_handling, |
| 7947 | view, |
| 7948 | view_address, |
| 7949 | view_size); |
| 7950 | else if (sh_type == elfcpp::SHT_RELA) |
| 7951 | // We do not support RELA type relocations yet. This is provided for |
| 7952 | // completeness. |
| 7953 | this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>( |
| 7954 | relinfo, |
| 7955 | prelocs, |
| 7956 | reloc_count, |
| 7957 | output_section, |
| 7958 | needs_special_offset_handling, |
| 7959 | view, |
| 7960 | view_address, |
| 7961 | view_size); |
| 7962 | else |
| 7963 | gold_unreachable(); |
| 7964 | } |
| 7965 | |
| 7966 | // Group input sections for stub generation. |
| 7967 | // |
| 7968 | // We goup input sections in an output sections so that the total size, |
| 7969 | // including any padding space due to alignment is smaller than GROUP_SIZE |
| 7970 | // unless the only input section in group is bigger than GROUP_SIZE already. |
| 7971 | // Then an ARM stub table is created to follow the last input section |
| 7972 | // in group. For each group an ARM stub table is created an is placed |
| 7973 | // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further |
| 7974 | // extend the group after the stub table. |
| 7975 | |
| 7976 | template<bool big_endian> |
| 7977 | void |
| 7978 | Target_arm<big_endian>::group_sections( |
| 7979 | Layout* layout, |
| 7980 | section_size_type group_size, |
| 7981 | bool stubs_always_after_branch) |
| 7982 | { |
| 7983 | // Group input sections and insert stub table |
| 7984 | Layout::Section_list section_list; |
| 7985 | layout->get_allocated_sections(§ion_list); |
| 7986 | for (Layout::Section_list::const_iterator p = section_list.begin(); |
| 7987 | p != section_list.end(); |
| 7988 | ++p) |
| 7989 | { |
| 7990 | Arm_output_section<big_endian>* output_section = |
| 7991 | Arm_output_section<big_endian>::as_arm_output_section(*p); |
| 7992 | output_section->group_sections(group_size, stubs_always_after_branch, |
| 7993 | this); |
| 7994 | } |
| 7995 | } |
| 7996 | |
| 7997 | // Relaxation hook. This is where we do stub generation. |
| 7998 | |
| 7999 | template<bool big_endian> |
| 8000 | bool |
| 8001 | Target_arm<big_endian>::do_relax( |
| 8002 | int pass, |
| 8003 | const Input_objects* input_objects, |
| 8004 | Symbol_table* symtab, |
| 8005 | Layout* layout) |
| 8006 | { |
| 8007 | // No need to generate stubs if this is a relocatable link. |
| 8008 | gold_assert(!parameters->options().relocatable()); |
| 8009 | |
| 8010 | // If this is the first pass, we need to group input sections into |
| 8011 | // stub groups. |
| 8012 | if (pass == 1) |
| 8013 | { |
| 8014 | // Determine the stub group size. The group size is the absolute |
| 8015 | // value of the parameter --stub-group-size. If --stub-group-size |
| 8016 | // is passed a negative value, we restict stubs to be always after |
| 8017 | // the stubbed branches. |
| 8018 | int32_t stub_group_size_param = |
| 8019 | parameters->options().stub_group_size(); |
| 8020 | bool stubs_always_after_branch = stub_group_size_param < 0; |
| 8021 | section_size_type stub_group_size = abs(stub_group_size_param); |
| 8022 | |
| 8023 | // The Cortex-A8 erratum fix depends on stubs not being in the same 4K |
| 8024 | // page as the first half of a 32-bit branch straddling two 4K pages. |
| 8025 | // This is a crude way of enforcing that. |
| 8026 | if (this->fix_cortex_a8_) |
| 8027 | stubs_always_after_branch = true; |
| 8028 | |
| 8029 | if (stub_group_size == 1) |
| 8030 | { |
| 8031 | // Default value. |
| 8032 | // Thumb branch range is +-4MB has to be used as the default |
| 8033 | // maximum size (a given section can contain both ARM and Thumb |
| 8034 | // code, so the worst case has to be taken into account). |
| 8035 | // |
| 8036 | // This value is 24K less than that, which allows for 2025 |
| 8037 | // 12-byte stubs. If we exceed that, then we will fail to link. |
| 8038 | // The user will have to relink with an explicit group size |
| 8039 | // option. |
| 8040 | stub_group_size = 4170000; |
| 8041 | } |
| 8042 | |
| 8043 | group_sections(layout, stub_group_size, stubs_always_after_branch); |
| 8044 | } |
| 8045 | |
| 8046 | // The Cortex-A8 stubs are sensitive to layout of code sections. At the |
| 8047 | // beginning of each relaxation pass, just blow away all the stubs. |
| 8048 | // Alternatively, we could selectively remove only the stubs and reloc |
| 8049 | // information for code sections that have moved since the last pass. |
| 8050 | // That would require more book-keeping. |
| 8051 | typedef typename Stub_table_list::iterator Stub_table_iterator; |
| 8052 | if (this->fix_cortex_a8_) |
| 8053 | { |
| 8054 | // Clear all Cortex-A8 reloc information. |
| 8055 | for (typename Cortex_a8_relocs_info::const_iterator p = |
| 8056 | this->cortex_a8_relocs_info_.begin(); |
| 8057 | p != this->cortex_a8_relocs_info_.end(); |
| 8058 | ++p) |
| 8059 | delete p->second; |
| 8060 | this->cortex_a8_relocs_info_.clear(); |
| 8061 | |
| 8062 | // Remove all Cortex-A8 stubs. |
| 8063 | for (Stub_table_iterator sp = this->stub_tables_.begin(); |
| 8064 | sp != this->stub_tables_.end(); |
| 8065 | ++sp) |
| 8066 | (*sp)->remove_all_cortex_a8_stubs(); |
| 8067 | } |
| 8068 | |
| 8069 | // Scan relocs for relocation stubs |
| 8070 | for (Input_objects::Relobj_iterator op = input_objects->relobj_begin(); |
| 8071 | op != input_objects->relobj_end(); |
| 8072 | ++op) |
| 8073 | { |
| 8074 | Arm_relobj<big_endian>* arm_relobj = |
| 8075 | Arm_relobj<big_endian>::as_arm_relobj(*op); |
| 8076 | arm_relobj->scan_sections_for_stubs(this, symtab, layout); |
| 8077 | } |
| 8078 | |
| 8079 | // Check all stub tables to see if any of them have their data sizes |
| 8080 | // or addresses alignments changed. These are the only things that |
| 8081 | // matter. |
| 8082 | bool any_stub_table_changed = false; |
| 8083 | for (Stub_table_iterator sp = this->stub_tables_.begin(); |
| 8084 | (sp != this->stub_tables_.end()) && !any_stub_table_changed; |
| 8085 | ++sp) |
| 8086 | { |
| 8087 | if ((*sp)->update_data_size_and_addralign()) |
| 8088 | any_stub_table_changed = true; |
| 8089 | } |
| 8090 | |
| 8091 | // Finalize the stubs in the last relaxation pass. |
| 8092 | if (!any_stub_table_changed) |
| 8093 | for (Stub_table_iterator sp = this->stub_tables_.begin(); |
| 8094 | (sp != this->stub_tables_.end()) && !any_stub_table_changed; |
| 8095 | ++sp) |
| 8096 | (*sp)->finalize_stubs(); |
| 8097 | |
| 8098 | return any_stub_table_changed; |
| 8099 | } |
| 8100 | |
| 8101 | // Relocate a stub. |
| 8102 | |
| 8103 | template<bool big_endian> |
| 8104 | void |
| 8105 | Target_arm<big_endian>::relocate_stub( |
| 8106 | Stub* stub, |
| 8107 | const Relocate_info<32, big_endian>* relinfo, |
| 8108 | Output_section* output_section, |
| 8109 | unsigned char* view, |
| 8110 | Arm_address address, |
| 8111 | section_size_type view_size) |
| 8112 | { |
| 8113 | Relocate relocate; |
| 8114 | const Stub_template* stub_template = stub->stub_template(); |
| 8115 | for (size_t i = 0; i < stub_template->reloc_count(); i++) |
| 8116 | { |
| 8117 | size_t reloc_insn_index = stub_template->reloc_insn_index(i); |
| 8118 | const Insn_template* insn = &stub_template->insns()[reloc_insn_index]; |
| 8119 | |
| 8120 | unsigned int r_type = insn->r_type(); |
| 8121 | section_size_type reloc_offset = stub_template->reloc_offset(i); |
| 8122 | section_size_type reloc_size = insn->size(); |
| 8123 | gold_assert(reloc_offset + reloc_size <= view_size); |
| 8124 | |
| 8125 | // This is the address of the stub destination. |
| 8126 | Arm_address target = stub->reloc_target(i) + insn->reloc_addend(); |
| 8127 | Symbol_value<32> symval; |
| 8128 | symval.set_output_value(target); |
| 8129 | |
| 8130 | // Synthesize a fake reloc just in case. We don't have a symbol so |
| 8131 | // we use 0. |
| 8132 | unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size]; |
| 8133 | memset(reloc_buffer, 0, sizeof(reloc_buffer)); |
| 8134 | elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer); |
| 8135 | reloc_write.put_r_offset(reloc_offset); |
| 8136 | reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type)); |
| 8137 | elfcpp::Rel<32, big_endian> rel(reloc_buffer); |
| 8138 | |
| 8139 | relocate.relocate(relinfo, this, output_section, |
| 8140 | this->fake_relnum_for_stubs, rel, r_type, |
| 8141 | NULL, &symval, view + reloc_offset, |
| 8142 | address + reloc_offset, reloc_size); |
| 8143 | } |
| 8144 | } |
| 8145 | |
| 8146 | // Determine whether an object attribute tag takes an integer, a |
| 8147 | // string or both. |
| 8148 | |
| 8149 | template<bool big_endian> |
| 8150 | int |
| 8151 | Target_arm<big_endian>::do_attribute_arg_type(int tag) const |
| 8152 | { |
| 8153 | if (tag == Object_attribute::Tag_compatibility) |
| 8154 | return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL |
| 8155 | | Object_attribute::ATTR_TYPE_FLAG_STR_VAL); |
| 8156 | else if (tag == elfcpp::Tag_nodefaults) |
| 8157 | return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL |
| 8158 | | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT); |
| 8159 | else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name) |
| 8160 | return Object_attribute::ATTR_TYPE_FLAG_STR_VAL; |
| 8161 | else if (tag < 32) |
| 8162 | return Object_attribute::ATTR_TYPE_FLAG_INT_VAL; |
| 8163 | else |
| 8164 | return ((tag & 1) != 0 |
| 8165 | ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL |
| 8166 | : Object_attribute::ATTR_TYPE_FLAG_INT_VAL); |
| 8167 | } |
| 8168 | |
| 8169 | // Reorder attributes. |
| 8170 | // |
| 8171 | // The ABI defines that Tag_conformance should be emitted first, and that |
| 8172 | // Tag_nodefaults should be second (if either is defined). This sets those |
| 8173 | // two positions, and bumps up the position of all the remaining tags to |
| 8174 | // compensate. |
| 8175 | |
| 8176 | template<bool big_endian> |
| 8177 | int |
| 8178 | Target_arm<big_endian>::do_attributes_order(int num) const |
| 8179 | { |
| 8180 | // Reorder the known object attributes in output. We want to move |
| 8181 | // Tag_conformance to position 4 and Tag_conformance to position 5 |
| 8182 | // and shift eveything between 4 .. Tag_conformance - 1 to make room. |
| 8183 | if (num == 4) |
| 8184 | return elfcpp::Tag_conformance; |
| 8185 | if (num == 5) |
| 8186 | return elfcpp::Tag_nodefaults; |
| 8187 | if ((num - 2) < elfcpp::Tag_nodefaults) |
| 8188 | return num - 2; |
| 8189 | if ((num - 1) < elfcpp::Tag_conformance) |
| 8190 | return num - 1; |
| 8191 | return num; |
| 8192 | } |
| 8193 | |
| 8194 | // Scan a span of THUMB code for Cortex-A8 erratum. |
| 8195 | |
| 8196 | template<bool big_endian> |
| 8197 | void |
| 8198 | Target_arm<big_endian>::scan_span_for_cortex_a8_erratum( |
| 8199 | Arm_relobj<big_endian>* arm_relobj, |
| 8200 | unsigned int shndx, |
| 8201 | section_size_type span_start, |
| 8202 | section_size_type span_end, |
| 8203 | const unsigned char* view, |
| 8204 | Arm_address address) |
| 8205 | { |
| 8206 | // Scan for 32-bit Thumb-2 branches which span two 4K regions, where: |
| 8207 | // |
| 8208 | // The opcode is BLX.W, BL.W, B.W, Bcc.W |
| 8209 | // The branch target is in the same 4KB region as the |
| 8210 | // first half of the branch. |
| 8211 | // The instruction before the branch is a 32-bit |
| 8212 | // length non-branch instruction. |
| 8213 | section_size_type i = span_start; |
| 8214 | bool last_was_32bit = false; |
| 8215 | bool last_was_branch = false; |
| 8216 | while (i < span_end) |
| 8217 | { |
| 8218 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 8219 | const Valtype* wv = reinterpret_cast<const Valtype*>(view + i); |
| 8220 | uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 8221 | bool is_blx = false, is_b = false; |
| 8222 | bool is_bl = false, is_bcc = false; |
| 8223 | |
| 8224 | bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000; |
| 8225 | if (insn_32bit) |
| 8226 | { |
| 8227 | // Load the rest of the insn (in manual-friendly order). |
| 8228 | insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 8229 | |
| 8230 | // Encoding T4: B<c>.W. |
| 8231 | is_b = (insn & 0xf800d000U) == 0xf0009000U; |
| 8232 | // Encoding T1: BL<c>.W. |
| 8233 | is_bl = (insn & 0xf800d000U) == 0xf000d000U; |
| 8234 | // Encoding T2: BLX<c>.W. |
| 8235 | is_blx = (insn & 0xf800d000U) == 0xf000c000U; |
| 8236 | // Encoding T3: B<c>.W (not permitted in IT block). |
| 8237 | is_bcc = ((insn & 0xf800d000U) == 0xf0008000U |
| 8238 | && (insn & 0x07f00000U) != 0x03800000U); |
| 8239 | } |
| 8240 | |
| 8241 | bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc; |
| 8242 | |
| 8243 | // If this instruction is a 32-bit THUMB branch that crosses a 4K |
| 8244 | // page boundary and it follows 32-bit non-branch instruction, |
| 8245 | // we need to work around. |
| 8246 | if (is_32bit_branch |
| 8247 | && ((address + i) & 0xfffU) == 0xffeU |
| 8248 | && last_was_32bit |
| 8249 | && !last_was_branch) |
| 8250 | { |
| 8251 | // Check to see if there is a relocation stub for this branch. |
| 8252 | bool force_target_arm = false; |
| 8253 | bool force_target_thumb = false; |
| 8254 | const Cortex_a8_reloc* cortex_a8_reloc = NULL; |
| 8255 | Cortex_a8_relocs_info::const_iterator p = |
| 8256 | this->cortex_a8_relocs_info_.find(address + i); |
| 8257 | |
| 8258 | if (p != this->cortex_a8_relocs_info_.end()) |
| 8259 | { |
| 8260 | cortex_a8_reloc = p->second; |
| 8261 | bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0; |
| 8262 | |
| 8263 | if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL |
| 8264 | && !target_is_thumb) |
| 8265 | force_target_arm = true; |
| 8266 | else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL |
| 8267 | && target_is_thumb) |
| 8268 | force_target_thumb = true; |
| 8269 | } |
| 8270 | |
| 8271 | off_t offset; |
| 8272 | Stub_type stub_type = arm_stub_none; |
| 8273 | |
| 8274 | // Check if we have an offending branch instruction. |
| 8275 | uint16_t upper_insn = (insn >> 16) & 0xffffU; |
| 8276 | uint16_t lower_insn = insn & 0xffffU; |
| 8277 | typedef struct Arm_relocate_functions<big_endian> RelocFuncs; |
| 8278 | |
| 8279 | if (cortex_a8_reloc != NULL |
| 8280 | && cortex_a8_reloc->reloc_stub() != NULL) |
| 8281 | // We've already made a stub for this instruction, e.g. |
| 8282 | // it's a long branch or a Thumb->ARM stub. Assume that |
| 8283 | // stub will suffice to work around the A8 erratum (see |
| 8284 | // setting of always_after_branch above). |
| 8285 | ; |
| 8286 | else if (is_bcc) |
| 8287 | { |
| 8288 | offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn, |
| 8289 | lower_insn); |
| 8290 | stub_type = arm_stub_a8_veneer_b_cond; |
| 8291 | } |
| 8292 | else if (is_b || is_bl || is_blx) |
| 8293 | { |
| 8294 | offset = RelocFuncs::thumb32_branch_offset(upper_insn, |
| 8295 | lower_insn); |
| 8296 | if (is_blx) |
| 8297 | offset &= ~3; |
| 8298 | |
| 8299 | stub_type = (is_blx |
| 8300 | ? arm_stub_a8_veneer_blx |
| 8301 | : (is_bl |
| 8302 | ? arm_stub_a8_veneer_bl |
| 8303 | : arm_stub_a8_veneer_b)); |
| 8304 | } |
| 8305 | |
| 8306 | if (stub_type != arm_stub_none) |
| 8307 | { |
| 8308 | Arm_address pc_for_insn = address + i + 4; |
| 8309 | |
| 8310 | // The original instruction is a BL, but the target is |
| 8311 | // an ARM instruction. If we were not making a stub, |
| 8312 | // the BL would have been converted to a BLX. Use the |
| 8313 | // BLX stub instead in that case. |
| 8314 | if (this->may_use_blx() && force_target_arm |
| 8315 | && stub_type == arm_stub_a8_veneer_bl) |
| 8316 | { |
| 8317 | stub_type = arm_stub_a8_veneer_blx; |
| 8318 | is_blx = true; |
| 8319 | is_bl = false; |
| 8320 | } |
| 8321 | // Conversely, if the original instruction was |
| 8322 | // BLX but the target is Thumb mode, use the BL stub. |
| 8323 | else if (force_target_thumb |
| 8324 | && stub_type == arm_stub_a8_veneer_blx) |
| 8325 | { |
| 8326 | stub_type = arm_stub_a8_veneer_bl; |
| 8327 | is_blx = false; |
| 8328 | is_bl = true; |
| 8329 | } |
| 8330 | |
| 8331 | if (is_blx) |
| 8332 | pc_for_insn &= ~3; |
| 8333 | |
| 8334 | // If we found a relocation, use the proper destination, |
| 8335 | // not the offset in the (unrelocated) instruction. |
| 8336 | // Note this is always done if we switched the stub type above. |
| 8337 | if (cortex_a8_reloc != NULL) |
| 8338 | offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn); |
| 8339 | |
| 8340 | Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1); |
| 8341 | |
| 8342 | // Add a new stub if destination address in in the same page. |
| 8343 | if (((address + i) & ~0xfffU) == (target & ~0xfffU)) |
| 8344 | { |
| 8345 | Cortex_a8_stub* stub = |
| 8346 | this->stub_factory_.make_cortex_a8_stub(stub_type, |
| 8347 | arm_relobj, shndx, |
| 8348 | address + i, |
| 8349 | target, insn); |
| 8350 | Stub_table<big_endian>* stub_table = |
| 8351 | arm_relobj->stub_table(shndx); |
| 8352 | gold_assert(stub_table != NULL); |
| 8353 | stub_table->add_cortex_a8_stub(address + i, stub); |
| 8354 | } |
| 8355 | } |
| 8356 | } |
| 8357 | |
| 8358 | i += insn_32bit ? 4 : 2; |
| 8359 | last_was_32bit = insn_32bit; |
| 8360 | last_was_branch = is_32bit_branch; |
| 8361 | } |
| 8362 | } |
| 8363 | |
| 8364 | // Apply the Cortex-A8 workaround. |
| 8365 | |
| 8366 | template<bool big_endian> |
| 8367 | void |
| 8368 | Target_arm<big_endian>::apply_cortex_a8_workaround( |
| 8369 | const Cortex_a8_stub* stub, |
| 8370 | Arm_address stub_address, |
| 8371 | unsigned char* insn_view, |
| 8372 | Arm_address insn_address) |
| 8373 | { |
| 8374 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 8375 | Valtype* wv = reinterpret_cast<Valtype*>(insn_view); |
| 8376 | Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 8377 | Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 8378 | off_t branch_offset = stub_address - (insn_address + 4); |
| 8379 | |
| 8380 | typedef struct Arm_relocate_functions<big_endian> RelocFuncs; |
| 8381 | switch (stub->stub_template()->type()) |
| 8382 | { |
| 8383 | case arm_stub_a8_veneer_b_cond: |
| 8384 | gold_assert(!utils::has_overflow<21>(branch_offset)); |
| 8385 | upper_insn = RelocFuncs::thumb32_cond_branch_upper(upper_insn, |
| 8386 | branch_offset); |
| 8387 | lower_insn = RelocFuncs::thumb32_cond_branch_lower(lower_insn, |
| 8388 | branch_offset); |
| 8389 | break; |
| 8390 | |
| 8391 | case arm_stub_a8_veneer_b: |
| 8392 | case arm_stub_a8_veneer_bl: |
| 8393 | case arm_stub_a8_veneer_blx: |
| 8394 | if ((lower_insn & 0x5000U) == 0x4000U) |
| 8395 | // For a BLX instruction, make sure that the relocation is |
| 8396 | // rounded up to a word boundary. This follows the semantics of |
| 8397 | // the instruction which specifies that bit 1 of the target |
| 8398 | // address will come from bit 1 of the base address. |
| 8399 | branch_offset = (branch_offset + 2) & ~3; |
| 8400 | |
| 8401 | // Put BRANCH_OFFSET back into the insn. |
| 8402 | gold_assert(!utils::has_overflow<25>(branch_offset)); |
| 8403 | upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset); |
| 8404 | lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset); |
| 8405 | break; |
| 8406 | |
| 8407 | default: |
| 8408 | gold_unreachable(); |
| 8409 | } |
| 8410 | |
| 8411 | // Put the relocated value back in the object file: |
| 8412 | elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn); |
| 8413 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn); |
| 8414 | } |
| 8415 | |
| 8416 | template<bool big_endian> |
| 8417 | class Target_selector_arm : public Target_selector |
| 8418 | { |
| 8419 | public: |
| 8420 | Target_selector_arm() |
| 8421 | : Target_selector(elfcpp::EM_ARM, 32, big_endian, |
| 8422 | (big_endian ? "elf32-bigarm" : "elf32-littlearm")) |
| 8423 | { } |
| 8424 | |
| 8425 | Target* |
| 8426 | do_instantiate_target() |
| 8427 | { return new Target_arm<big_endian>(); } |
| 8428 | }; |
| 8429 | |
| 8430 | Target_selector_arm<false> target_selector_arm; |
| 8431 | Target_selector_arm<true> target_selector_armbe; |
| 8432 | |
| 8433 | } // End anonymous namespace. |