| 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 | |
| 34 | #include "elfcpp.h" |
| 35 | #include "parameters.h" |
| 36 | #include "reloc.h" |
| 37 | #include "arm.h" |
| 38 | #include "object.h" |
| 39 | #include "symtab.h" |
| 40 | #include "layout.h" |
| 41 | #include "output.h" |
| 42 | #include "copy-relocs.h" |
| 43 | #include "target.h" |
| 44 | #include "target-reloc.h" |
| 45 | #include "target-select.h" |
| 46 | #include "tls.h" |
| 47 | #include "defstd.h" |
| 48 | #include "gc.h" |
| 49 | |
| 50 | namespace |
| 51 | { |
| 52 | |
| 53 | using namespace gold; |
| 54 | |
| 55 | template<bool big_endian> |
| 56 | class Output_data_plt_arm; |
| 57 | |
| 58 | template<bool big_endian> |
| 59 | class Stub_table; |
| 60 | |
| 61 | template<bool big_endian> |
| 62 | class Arm_input_section; |
| 63 | |
| 64 | template<bool big_endian> |
| 65 | class Arm_output_section; |
| 66 | |
| 67 | template<bool big_endian> |
| 68 | class Arm_relobj; |
| 69 | |
| 70 | template<bool big_endian> |
| 71 | class Target_arm; |
| 72 | |
| 73 | // For convenience. |
| 74 | typedef elfcpp::Elf_types<32>::Elf_Addr Arm_address; |
| 75 | |
| 76 | // Maximum branch offsets for ARM, THUMB and THUMB2. |
| 77 | const int32_t ARM_MAX_FWD_BRANCH_OFFSET = ((((1 << 23) - 1) << 2) + 8); |
| 78 | const int32_t ARM_MAX_BWD_BRANCH_OFFSET = ((-((1 << 23) << 2)) + 8); |
| 79 | const int32_t THM_MAX_FWD_BRANCH_OFFSET = ((1 << 22) -2 + 4); |
| 80 | const int32_t THM_MAX_BWD_BRANCH_OFFSET = (-(1 << 22) + 4); |
| 81 | const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4); |
| 82 | const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4); |
| 83 | |
| 84 | // The arm target class. |
| 85 | // |
| 86 | // This is a very simple port of gold for ARM-EABI. It is intended for |
| 87 | // supporting Android only for the time being. Only these relocation types |
| 88 | // are supported. |
| 89 | // |
| 90 | // R_ARM_NONE |
| 91 | // R_ARM_ABS32 |
| 92 | // R_ARM_ABS32_NOI |
| 93 | // R_ARM_ABS16 |
| 94 | // R_ARM_ABS12 |
| 95 | // R_ARM_ABS8 |
| 96 | // R_ARM_THM_ABS5 |
| 97 | // R_ARM_BASE_ABS |
| 98 | // R_ARM_REL32 |
| 99 | // R_ARM_THM_CALL |
| 100 | // R_ARM_COPY |
| 101 | // R_ARM_GLOB_DAT |
| 102 | // R_ARM_BASE_PREL |
| 103 | // R_ARM_JUMP_SLOT |
| 104 | // R_ARM_RELATIVE |
| 105 | // R_ARM_GOTOFF32 |
| 106 | // R_ARM_GOT_BREL |
| 107 | // R_ARM_GOT_PREL |
| 108 | // R_ARM_PLT32 |
| 109 | // R_ARM_CALL |
| 110 | // R_ARM_JUMP24 |
| 111 | // R_ARM_TARGET1 |
| 112 | // R_ARM_PREL31 |
| 113 | // R_ARM_ABS8 |
| 114 | // R_ARM_MOVW_ABS_NC |
| 115 | // R_ARM_MOVT_ABS |
| 116 | // R_ARM_THM_MOVW_ABS_NC |
| 117 | // R_ARM_THM_MOVT_ABS |
| 118 | // R_ARM_MOVW_PREL_NC |
| 119 | // R_ARM_MOVT_PREL |
| 120 | // R_ARM_THM_MOVW_PREL_NC |
| 121 | // R_ARM_THM_MOVT_PREL |
| 122 | // |
| 123 | // TODOs: |
| 124 | // - Generate various branch stubs. |
| 125 | // - Support interworking. |
| 126 | // - Define section symbols __exidx_start and __exidx_stop. |
| 127 | // - Support more relocation types as needed. |
| 128 | // - Make PLTs more flexible for different architecture features like |
| 129 | // Thumb-2 and BE8. |
| 130 | // There are probably a lot more. |
| 131 | |
| 132 | // Instruction template class. This class is similar to the insn_sequence |
| 133 | // struct in bfd/elf32-arm.c. |
| 134 | |
| 135 | class Insn_template |
| 136 | { |
| 137 | public: |
| 138 | // Types of instruction templates. |
| 139 | enum Type |
| 140 | { |
| 141 | THUMB16_TYPE = 1, |
| 142 | THUMB32_TYPE, |
| 143 | ARM_TYPE, |
| 144 | DATA_TYPE |
| 145 | }; |
| 146 | |
| 147 | // Factory methods to create instrunction templates in different formats. |
| 148 | |
| 149 | static const Insn_template |
| 150 | thumb16_insn(uint32_t data) |
| 151 | { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); } |
| 152 | |
| 153 | // A bit of a hack. A Thumb conditional branch, in which the proper |
| 154 | // condition is inserted when we build the stub. |
| 155 | static const Insn_template |
| 156 | thumb16_bcond_insn(uint32_t data) |
| 157 | { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 1); } |
| 158 | |
| 159 | static const Insn_template |
| 160 | thumb32_insn(uint32_t data) |
| 161 | { return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_NONE, 0); } |
| 162 | |
| 163 | static const Insn_template |
| 164 | thumb32_b_insn(uint32_t data, int reloc_addend) |
| 165 | { |
| 166 | return Insn_template(data, THUMB32_TYPE, elfcpp::R_ARM_THM_JUMP24, |
| 167 | reloc_addend); |
| 168 | } |
| 169 | |
| 170 | static const Insn_template |
| 171 | arm_insn(uint32_t data) |
| 172 | { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_NONE, 0); } |
| 173 | |
| 174 | static const Insn_template |
| 175 | arm_rel_insn(unsigned data, int reloc_addend) |
| 176 | { return Insn_template(data, ARM_TYPE, elfcpp::R_ARM_JUMP24, reloc_addend); } |
| 177 | |
| 178 | static const Insn_template |
| 179 | data_word(unsigned data, unsigned int r_type, int reloc_addend) |
| 180 | { return Insn_template(data, DATA_TYPE, r_type, reloc_addend); } |
| 181 | |
| 182 | // Accessors. This class is used for read-only objects so no modifiers |
| 183 | // are provided. |
| 184 | |
| 185 | uint32_t |
| 186 | data() const |
| 187 | { return this->data_; } |
| 188 | |
| 189 | // Return the instruction sequence type of this. |
| 190 | Type |
| 191 | type() const |
| 192 | { return this->type_; } |
| 193 | |
| 194 | // Return the ARM relocation type of this. |
| 195 | unsigned int |
| 196 | r_type() const |
| 197 | { return this->r_type_; } |
| 198 | |
| 199 | int32_t |
| 200 | reloc_addend() const |
| 201 | { return this->reloc_addend_; } |
| 202 | |
| 203 | // Return size of instrunction template in bytes. |
| 204 | size_t |
| 205 | size() const; |
| 206 | |
| 207 | // Return byte-alignment of instrunction template. |
| 208 | unsigned |
| 209 | alignment() const; |
| 210 | |
| 211 | private: |
| 212 | // We make the constructor private to ensure that only the factory |
| 213 | // methods are used. |
| 214 | inline |
| 215 | Insn_template(unsigned data, Type type, unsigned int r_type, int reloc_addend) |
| 216 | : data_(data), type_(type), r_type_(r_type), reloc_addend_(reloc_addend) |
| 217 | { } |
| 218 | |
| 219 | // Instruction specific data. This is used to store information like |
| 220 | // some of the instruction bits. |
| 221 | uint32_t data_; |
| 222 | // Instruction template type. |
| 223 | Type type_; |
| 224 | // Relocation type if there is a relocation or R_ARM_NONE otherwise. |
| 225 | unsigned int r_type_; |
| 226 | // Relocation addend. |
| 227 | int32_t reloc_addend_; |
| 228 | }; |
| 229 | |
| 230 | // Macro for generating code to stub types. One entry per long/short |
| 231 | // branch stub |
| 232 | |
| 233 | #define DEF_STUBS \ |
| 234 | DEF_STUB(long_branch_any_any) \ |
| 235 | DEF_STUB(long_branch_v4t_arm_thumb) \ |
| 236 | DEF_STUB(long_branch_thumb_only) \ |
| 237 | DEF_STUB(long_branch_v4t_thumb_thumb) \ |
| 238 | DEF_STUB(long_branch_v4t_thumb_arm) \ |
| 239 | DEF_STUB(short_branch_v4t_thumb_arm) \ |
| 240 | DEF_STUB(long_branch_any_arm_pic) \ |
| 241 | DEF_STUB(long_branch_any_thumb_pic) \ |
| 242 | DEF_STUB(long_branch_v4t_thumb_thumb_pic) \ |
| 243 | DEF_STUB(long_branch_v4t_arm_thumb_pic) \ |
| 244 | DEF_STUB(long_branch_v4t_thumb_arm_pic) \ |
| 245 | DEF_STUB(long_branch_thumb_only_pic) \ |
| 246 | DEF_STUB(a8_veneer_b_cond) \ |
| 247 | DEF_STUB(a8_veneer_b) \ |
| 248 | DEF_STUB(a8_veneer_bl) \ |
| 249 | DEF_STUB(a8_veneer_blx) |
| 250 | |
| 251 | // Stub types. |
| 252 | |
| 253 | #define DEF_STUB(x) arm_stub_##x, |
| 254 | typedef enum |
| 255 | { |
| 256 | arm_stub_none, |
| 257 | DEF_STUBS |
| 258 | |
| 259 | // First reloc stub type. |
| 260 | arm_stub_reloc_first = arm_stub_long_branch_any_any, |
| 261 | // Last reloc stub type. |
| 262 | arm_stub_reloc_last = arm_stub_long_branch_thumb_only_pic, |
| 263 | |
| 264 | // First Cortex-A8 stub type. |
| 265 | arm_stub_cortex_a8_first = arm_stub_a8_veneer_b_cond, |
| 266 | // Last Cortex-A8 stub type. |
| 267 | arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx, |
| 268 | |
| 269 | // Last stub type. |
| 270 | arm_stub_type_last = arm_stub_a8_veneer_blx |
| 271 | } Stub_type; |
| 272 | #undef DEF_STUB |
| 273 | |
| 274 | // Stub template class. Templates are meant to be read-only objects. |
| 275 | // A stub template for a stub type contains all read-only attributes |
| 276 | // common to all stubs of the same type. |
| 277 | |
| 278 | class Stub_template |
| 279 | { |
| 280 | public: |
| 281 | Stub_template(Stub_type, const Insn_template*, size_t); |
| 282 | |
| 283 | ~Stub_template() |
| 284 | { } |
| 285 | |
| 286 | // Return stub type. |
| 287 | Stub_type |
| 288 | type() const |
| 289 | { return this->type_; } |
| 290 | |
| 291 | // Return an array of instruction templates. |
| 292 | const Insn_template* |
| 293 | insns() const |
| 294 | { return this->insns_; } |
| 295 | |
| 296 | // Return size of template in number of instructions. |
| 297 | size_t |
| 298 | insn_count() const |
| 299 | { return this->insn_count_; } |
| 300 | |
| 301 | // Return size of template in bytes. |
| 302 | size_t |
| 303 | size() const |
| 304 | { return this->size_; } |
| 305 | |
| 306 | // Return alignment of the stub template. |
| 307 | unsigned |
| 308 | alignment() const |
| 309 | { return this->alignment_; } |
| 310 | |
| 311 | // Return whether entry point is in thumb mode. |
| 312 | bool |
| 313 | entry_in_thumb_mode() const |
| 314 | { return this->entry_in_thumb_mode_; } |
| 315 | |
| 316 | // Return number of relocations in this template. |
| 317 | size_t |
| 318 | reloc_count() const |
| 319 | { return this->relocs_.size(); } |
| 320 | |
| 321 | // Return index of the I-th instruction with relocation. |
| 322 | size_t |
| 323 | reloc_insn_index(size_t i) const |
| 324 | { |
| 325 | gold_assert(i < this->relocs_.size()); |
| 326 | return this->relocs_[i].first; |
| 327 | } |
| 328 | |
| 329 | // Return the offset of the I-th instruction with relocation from the |
| 330 | // beginning of the stub. |
| 331 | section_size_type |
| 332 | reloc_offset(size_t i) const |
| 333 | { |
| 334 | gold_assert(i < this->relocs_.size()); |
| 335 | return this->relocs_[i].second; |
| 336 | } |
| 337 | |
| 338 | private: |
| 339 | // This contains information about an instruction template with a relocation |
| 340 | // and its offset from start of stub. |
| 341 | typedef std::pair<size_t, section_size_type> Reloc; |
| 342 | |
| 343 | // A Stub_template may not be copied. We want to share templates as much |
| 344 | // as possible. |
| 345 | Stub_template(const Stub_template&); |
| 346 | Stub_template& operator=(const Stub_template&); |
| 347 | |
| 348 | // Stub type. |
| 349 | Stub_type type_; |
| 350 | // Points to an array of Insn_templates. |
| 351 | const Insn_template* insns_; |
| 352 | // Number of Insn_templates in insns_[]. |
| 353 | size_t insn_count_; |
| 354 | // Size of templated instructions in bytes. |
| 355 | size_t size_; |
| 356 | // Alignment of templated instructions. |
| 357 | unsigned alignment_; |
| 358 | // Flag to indicate if entry is in thumb mode. |
| 359 | bool entry_in_thumb_mode_; |
| 360 | // A table of reloc instruction indices and offsets. We can find these by |
| 361 | // looking at the instruction templates but we pre-compute and then stash |
| 362 | // them here for speed. |
| 363 | std::vector<Reloc> relocs_; |
| 364 | }; |
| 365 | |
| 366 | // |
| 367 | // A class for code stubs. This is a base class for different type of |
| 368 | // stubs used in the ARM target. |
| 369 | // |
| 370 | |
| 371 | class Stub |
| 372 | { |
| 373 | private: |
| 374 | static const section_offset_type invalid_offset = |
| 375 | static_cast<section_offset_type>(-1); |
| 376 | |
| 377 | public: |
| 378 | Stub(const Stub_template* stub_template) |
| 379 | : stub_template_(stub_template), offset_(invalid_offset) |
| 380 | { } |
| 381 | |
| 382 | virtual |
| 383 | ~Stub() |
| 384 | { } |
| 385 | |
| 386 | // Return the stub template. |
| 387 | const Stub_template* |
| 388 | stub_template() const |
| 389 | { return this->stub_template_; } |
| 390 | |
| 391 | // Return offset of code stub from beginning of its containing stub table. |
| 392 | section_offset_type |
| 393 | offset() const |
| 394 | { |
| 395 | gold_assert(this->offset_ != invalid_offset); |
| 396 | return this->offset_; |
| 397 | } |
| 398 | |
| 399 | // Set offset of code stub from beginning of its containing stub table. |
| 400 | void |
| 401 | set_offset(section_offset_type offset) |
| 402 | { this->offset_ = offset; } |
| 403 | |
| 404 | // Return the relocation target address of the i-th relocation in the |
| 405 | // stub. This must be defined in a child class. |
| 406 | Arm_address |
| 407 | reloc_target(size_t i) |
| 408 | { return this->do_reloc_target(i); } |
| 409 | |
| 410 | // Write a stub at output VIEW. BIG_ENDIAN select how a stub is written. |
| 411 | void |
| 412 | write(unsigned char* view, section_size_type view_size, bool big_endian) |
| 413 | { this->do_write(view, view_size, big_endian); } |
| 414 | |
| 415 | protected: |
| 416 | // This must be defined in the child class. |
| 417 | virtual Arm_address |
| 418 | do_reloc_target(size_t) = 0; |
| 419 | |
| 420 | // This must be defined in the child class. |
| 421 | virtual void |
| 422 | do_write(unsigned char*, section_size_type, bool) = 0; |
| 423 | |
| 424 | private: |
| 425 | // Its template. |
| 426 | const Stub_template* stub_template_; |
| 427 | // Offset within the section of containing this stub. |
| 428 | section_offset_type offset_; |
| 429 | }; |
| 430 | |
| 431 | // Reloc stub class. These are stubs we use to fix up relocation because |
| 432 | // of limited branch ranges. |
| 433 | |
| 434 | class Reloc_stub : public Stub |
| 435 | { |
| 436 | public: |
| 437 | static const unsigned int invalid_index = static_cast<unsigned int>(-1); |
| 438 | // We assume we never jump to this address. |
| 439 | static const Arm_address invalid_address = static_cast<Arm_address>(-1); |
| 440 | |
| 441 | // Return destination address. |
| 442 | Arm_address |
| 443 | destination_address() const |
| 444 | { |
| 445 | gold_assert(this->destination_address_ != this->invalid_address); |
| 446 | return this->destination_address_; |
| 447 | } |
| 448 | |
| 449 | // Set destination address. |
| 450 | void |
| 451 | set_destination_address(Arm_address address) |
| 452 | { |
| 453 | gold_assert(address != this->invalid_address); |
| 454 | this->destination_address_ = address; |
| 455 | } |
| 456 | |
| 457 | // Reset destination address. |
| 458 | void |
| 459 | reset_destination_address() |
| 460 | { this->destination_address_ = this->invalid_address; } |
| 461 | |
| 462 | // Determine stub type for a branch of a relocation of R_TYPE going |
| 463 | // from BRANCH_ADDRESS to BRANCH_TARGET. If TARGET_IS_THUMB is set, |
| 464 | // the branch target is a thumb instruction. TARGET is used for look |
| 465 | // up ARM-specific linker settings. |
| 466 | static Stub_type |
| 467 | stub_type_for_reloc(unsigned int r_type, Arm_address branch_address, |
| 468 | Arm_address branch_target, bool target_is_thumb); |
| 469 | |
| 470 | // Reloc_stub key. A key is logically a triplet of a stub type, a symbol |
| 471 | // and an addend. Since we treat global and local symbol differently, we |
| 472 | // use a Symbol object for a global symbol and a object-index pair for |
| 473 | // a local symbol. |
| 474 | class Key |
| 475 | { |
| 476 | public: |
| 477 | // If SYMBOL is not null, this is a global symbol, we ignore RELOBJ and |
| 478 | // R_SYM. Otherwise, this is a local symbol and RELOBJ must non-NULL |
| 479 | // and R_SYM must not be invalid_index. |
| 480 | Key(Stub_type stub_type, const Symbol* symbol, const Relobj* relobj, |
| 481 | unsigned int r_sym, int32_t addend) |
| 482 | : stub_type_(stub_type), addend_(addend) |
| 483 | { |
| 484 | if (symbol != NULL) |
| 485 | { |
| 486 | this->r_sym_ = Reloc_stub::invalid_index; |
| 487 | this->u_.symbol = symbol; |
| 488 | } |
| 489 | else |
| 490 | { |
| 491 | gold_assert(relobj != NULL && r_sym != invalid_index); |
| 492 | this->r_sym_ = r_sym; |
| 493 | this->u_.relobj = relobj; |
| 494 | } |
| 495 | } |
| 496 | |
| 497 | ~Key() |
| 498 | { } |
| 499 | |
| 500 | // Accessors: Keys are meant to be read-only object so no modifiers are |
| 501 | // provided. |
| 502 | |
| 503 | // Return stub type. |
| 504 | Stub_type |
| 505 | stub_type() const |
| 506 | { return this->stub_type_; } |
| 507 | |
| 508 | // Return the local symbol index or invalid_index. |
| 509 | unsigned int |
| 510 | r_sym() const |
| 511 | { return this->r_sym_; } |
| 512 | |
| 513 | // Return the symbol if there is one. |
| 514 | const Symbol* |
| 515 | symbol() const |
| 516 | { return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; } |
| 517 | |
| 518 | // Return the relobj if there is one. |
| 519 | const Relobj* |
| 520 | relobj() const |
| 521 | { return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; } |
| 522 | |
| 523 | // Whether this equals to another key k. |
| 524 | bool |
| 525 | eq(const Key& k) const |
| 526 | { |
| 527 | return ((this->stub_type_ == k.stub_type_) |
| 528 | && (this->r_sym_ == k.r_sym_) |
| 529 | && ((this->r_sym_ != Reloc_stub::invalid_index) |
| 530 | ? (this->u_.relobj == k.u_.relobj) |
| 531 | : (this->u_.symbol == k.u_.symbol)) |
| 532 | && (this->addend_ == k.addend_)); |
| 533 | } |
| 534 | |
| 535 | // Return a hash value. |
| 536 | size_t |
| 537 | hash_value() const |
| 538 | { |
| 539 | return (this->stub_type_ |
| 540 | ^ this->r_sym_ |
| 541 | ^ gold::string_hash<char>( |
| 542 | (this->r_sym_ != Reloc_stub::invalid_index) |
| 543 | ? this->u_.relobj->name().c_str() |
| 544 | : this->u_.symbol->name()) |
| 545 | ^ this->addend_); |
| 546 | } |
| 547 | |
| 548 | // Functors for STL associative containers. |
| 549 | struct hash |
| 550 | { |
| 551 | size_t |
| 552 | operator()(const Key& k) const |
| 553 | { return k.hash_value(); } |
| 554 | }; |
| 555 | |
| 556 | struct equal_to |
| 557 | { |
| 558 | bool |
| 559 | operator()(const Key& k1, const Key& k2) const |
| 560 | { return k1.eq(k2); } |
| 561 | }; |
| 562 | |
| 563 | // Name of key. This is mainly for debugging. |
| 564 | std::string |
| 565 | name() const; |
| 566 | |
| 567 | private: |
| 568 | // Stub type. |
| 569 | Stub_type stub_type_; |
| 570 | // If this is a local symbol, this is the index in the defining object. |
| 571 | // Otherwise, it is invalid_index for a global symbol. |
| 572 | unsigned int r_sym_; |
| 573 | // If r_sym_ is invalid index. This points to a global symbol. |
| 574 | // Otherwise, this points a relobj. We used the unsized and target |
| 575 | // independent Symbol and Relobj classes instead of Sized_symbol<32> and |
| 576 | // Arm_relobj. This is done to avoid making the stub class a template |
| 577 | // as most of the stub machinery is endianity-neutral. However, it |
| 578 | // may require a bit of casting done by users of this class. |
| 579 | union |
| 580 | { |
| 581 | const Symbol* symbol; |
| 582 | const Relobj* relobj; |
| 583 | } u_; |
| 584 | // Addend associated with a reloc. |
| 585 | int32_t addend_; |
| 586 | }; |
| 587 | |
| 588 | protected: |
| 589 | // Reloc_stubs are created via a stub factory. So these are protected. |
| 590 | Reloc_stub(const Stub_template* stub_template) |
| 591 | : Stub(stub_template), destination_address_(invalid_address) |
| 592 | { } |
| 593 | |
| 594 | ~Reloc_stub() |
| 595 | { } |
| 596 | |
| 597 | friend class Stub_factory; |
| 598 | |
| 599 | private: |
| 600 | // Return the relocation target address of the i-th relocation in the |
| 601 | // stub. |
| 602 | Arm_address |
| 603 | do_reloc_target(size_t i) |
| 604 | { |
| 605 | // All reloc stub have only one relocation. |
| 606 | gold_assert(i == 0); |
| 607 | return this->destination_address_; |
| 608 | } |
| 609 | |
| 610 | // A template to implement do_write below. |
| 611 | template<bool big_endian> |
| 612 | void inline |
| 613 | do_fixed_endian_write(unsigned char*, section_size_type); |
| 614 | |
| 615 | // Write a stub. |
| 616 | void |
| 617 | do_write(unsigned char* view, section_size_type view_size, bool big_endian); |
| 618 | |
| 619 | // Address of destination. |
| 620 | Arm_address destination_address_; |
| 621 | }; |
| 622 | |
| 623 | // Stub factory class. |
| 624 | |
| 625 | class Stub_factory |
| 626 | { |
| 627 | public: |
| 628 | // Return the unique instance of this class. |
| 629 | static const Stub_factory& |
| 630 | get_instance() |
| 631 | { |
| 632 | static Stub_factory singleton; |
| 633 | return singleton; |
| 634 | } |
| 635 | |
| 636 | // Make a relocation stub. |
| 637 | Reloc_stub* |
| 638 | make_reloc_stub(Stub_type stub_type) const |
| 639 | { |
| 640 | gold_assert(stub_type >= arm_stub_reloc_first |
| 641 | && stub_type <= arm_stub_reloc_last); |
| 642 | return new Reloc_stub(this->stub_templates_[stub_type]); |
| 643 | } |
| 644 | |
| 645 | private: |
| 646 | // Constructor and destructor are protected since we only return a single |
| 647 | // instance created in Stub_factory::get_instance(). |
| 648 | |
| 649 | Stub_factory(); |
| 650 | |
| 651 | // A Stub_factory may not be copied since it is a singleton. |
| 652 | Stub_factory(const Stub_factory&); |
| 653 | Stub_factory& operator=(Stub_factory&); |
| 654 | |
| 655 | // Stub templates. These are initialized in the constructor. |
| 656 | const Stub_template* stub_templates_[arm_stub_type_last+1]; |
| 657 | }; |
| 658 | |
| 659 | // A class to hold stubs for the ARM target. |
| 660 | |
| 661 | template<bool big_endian> |
| 662 | class Stub_table : public Output_data |
| 663 | { |
| 664 | public: |
| 665 | Stub_table(Arm_input_section<big_endian>* owner) |
| 666 | : Output_data(), addralign_(1), owner_(owner), has_been_changed_(false), |
| 667 | reloc_stubs_() |
| 668 | { } |
| 669 | |
| 670 | ~Stub_table() |
| 671 | { } |
| 672 | |
| 673 | // Owner of this stub table. |
| 674 | Arm_input_section<big_endian>* |
| 675 | owner() const |
| 676 | { return this->owner_; } |
| 677 | |
| 678 | // Whether this stub table is empty. |
| 679 | bool |
| 680 | empty() const |
| 681 | { return this->reloc_stubs_.empty(); } |
| 682 | |
| 683 | // Whether this has been changed. |
| 684 | bool |
| 685 | has_been_changed() const |
| 686 | { return this->has_been_changed_; } |
| 687 | |
| 688 | // Set the has-been-changed flag. |
| 689 | void |
| 690 | set_has_been_changed(bool value) |
| 691 | { this->has_been_changed_ = value; } |
| 692 | |
| 693 | // Return the current data size. |
| 694 | off_t |
| 695 | current_data_size() const |
| 696 | { return this->current_data_size_for_child(); } |
| 697 | |
| 698 | // Add a STUB with using KEY. Caller is reponsible for avoid adding |
| 699 | // if already a STUB with the same key has been added. |
| 700 | void |
| 701 | add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key); |
| 702 | |
| 703 | // Look up a relocation stub using KEY. Return NULL if there is none. |
| 704 | Reloc_stub* |
| 705 | find_reloc_stub(const Reloc_stub::Key& key) const |
| 706 | { |
| 707 | typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key); |
| 708 | return (p != this->reloc_stubs_.end()) ? p->second : NULL; |
| 709 | } |
| 710 | |
| 711 | // Relocate stubs in this stub table. |
| 712 | void |
| 713 | relocate_stubs(const Relocate_info<32, big_endian>*, |
| 714 | Target_arm<big_endian>*, Output_section*, |
| 715 | unsigned char*, Arm_address, section_size_type); |
| 716 | |
| 717 | protected: |
| 718 | // Write out section contents. |
| 719 | void |
| 720 | do_write(Output_file*); |
| 721 | |
| 722 | // Return the required alignment. |
| 723 | uint64_t |
| 724 | do_addralign() const |
| 725 | { return this->addralign_; } |
| 726 | |
| 727 | // Finalize data size. |
| 728 | void |
| 729 | set_final_data_size() |
| 730 | { this->set_data_size(this->current_data_size_for_child()); } |
| 731 | |
| 732 | // Reset address and file offset. |
| 733 | void |
| 734 | do_reset_address_and_file_offset(); |
| 735 | |
| 736 | private: |
| 737 | // Unordered map of stubs. |
| 738 | typedef |
| 739 | Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash, |
| 740 | Reloc_stub::Key::equal_to> |
| 741 | Reloc_stub_map; |
| 742 | |
| 743 | // Address alignment |
| 744 | uint64_t addralign_; |
| 745 | // Owner of this stub table. |
| 746 | Arm_input_section<big_endian>* owner_; |
| 747 | // This is set to true during relaxiong if the size of the stub table |
| 748 | // has been changed. |
| 749 | bool has_been_changed_; |
| 750 | // The relocation stubs. |
| 751 | Reloc_stub_map reloc_stubs_; |
| 752 | }; |
| 753 | |
| 754 | // A class to wrap an ordinary input section containing executable code. |
| 755 | |
| 756 | template<bool big_endian> |
| 757 | class Arm_input_section : public Output_relaxed_input_section |
| 758 | { |
| 759 | public: |
| 760 | Arm_input_section(Relobj* relobj, unsigned int shndx) |
| 761 | : Output_relaxed_input_section(relobj, shndx, 1), |
| 762 | original_addralign_(1), original_size_(0), stub_table_(NULL) |
| 763 | { } |
| 764 | |
| 765 | ~Arm_input_section() |
| 766 | { } |
| 767 | |
| 768 | // Initialize. |
| 769 | void |
| 770 | init(); |
| 771 | |
| 772 | // Whether this is a stub table owner. |
| 773 | bool |
| 774 | is_stub_table_owner() const |
| 775 | { return this->stub_table_ != NULL && this->stub_table_->owner() == this; } |
| 776 | |
| 777 | // Return the stub table. |
| 778 | Stub_table<big_endian>* |
| 779 | stub_table() const |
| 780 | { return this->stub_table_; } |
| 781 | |
| 782 | // Set the stub_table. |
| 783 | void |
| 784 | set_stub_table(Stub_table<big_endian>* stub_table) |
| 785 | { this->stub_table_ = stub_table; } |
| 786 | |
| 787 | // Downcast a base pointer to an Arm_input_section pointer. This is |
| 788 | // not type-safe but we only use Arm_input_section not the base class. |
| 789 | static Arm_input_section<big_endian>* |
| 790 | as_arm_input_section(Output_relaxed_input_section* poris) |
| 791 | { return static_cast<Arm_input_section<big_endian>*>(poris); } |
| 792 | |
| 793 | protected: |
| 794 | // Write data to output file. |
| 795 | void |
| 796 | do_write(Output_file*); |
| 797 | |
| 798 | // Return required alignment of this. |
| 799 | uint64_t |
| 800 | do_addralign() const |
| 801 | { |
| 802 | if (this->is_stub_table_owner()) |
| 803 | return std::max(this->stub_table_->addralign(), |
| 804 | this->original_addralign_); |
| 805 | else |
| 806 | return this->original_addralign_; |
| 807 | } |
| 808 | |
| 809 | // Finalize data size. |
| 810 | void |
| 811 | set_final_data_size(); |
| 812 | |
| 813 | // Reset address and file offset. |
| 814 | void |
| 815 | do_reset_address_and_file_offset(); |
| 816 | |
| 817 | // Output offset. |
| 818 | bool |
| 819 | do_output_offset(const Relobj* object, unsigned int shndx, |
| 820 | section_offset_type offset, |
| 821 | section_offset_type* poutput) const |
| 822 | { |
| 823 | if ((object == this->relobj()) |
| 824 | && (shndx == this->shndx()) |
| 825 | && (offset >= 0) |
| 826 | && (convert_types<uint64_t, section_offset_type>(offset) |
| 827 | <= this->original_size_)) |
| 828 | { |
| 829 | *poutput = offset; |
| 830 | return true; |
| 831 | } |
| 832 | else |
| 833 | return false; |
| 834 | } |
| 835 | |
| 836 | private: |
| 837 | // Copying is not allowed. |
| 838 | Arm_input_section(const Arm_input_section&); |
| 839 | Arm_input_section& operator=(const Arm_input_section&); |
| 840 | |
| 841 | // Address alignment of the original input section. |
| 842 | uint64_t original_addralign_; |
| 843 | // Section size of the original input section. |
| 844 | uint64_t original_size_; |
| 845 | // Stub table. |
| 846 | Stub_table<big_endian>* stub_table_; |
| 847 | }; |
| 848 | |
| 849 | // Arm output section class. This is defined mainly to add a number of |
| 850 | // stub generation methods. |
| 851 | |
| 852 | template<bool big_endian> |
| 853 | class Arm_output_section : public Output_section |
| 854 | { |
| 855 | public: |
| 856 | Arm_output_section(const char* name, elfcpp::Elf_Word type, |
| 857 | elfcpp::Elf_Xword flags) |
| 858 | : Output_section(name, type, flags) |
| 859 | { } |
| 860 | |
| 861 | ~Arm_output_section() |
| 862 | { } |
| 863 | |
| 864 | // Group input sections for stub generation. |
| 865 | void |
| 866 | group_sections(section_size_type, bool, Target_arm<big_endian>*); |
| 867 | |
| 868 | // Downcast a base pointer to an Arm_output_section pointer. This is |
| 869 | // not type-safe but we only use Arm_output_section not the base class. |
| 870 | static Arm_output_section<big_endian>* |
| 871 | as_arm_output_section(Output_section* os) |
| 872 | { return static_cast<Arm_output_section<big_endian>*>(os); } |
| 873 | |
| 874 | private: |
| 875 | // For convenience. |
| 876 | typedef Output_section::Input_section Input_section; |
| 877 | typedef Output_section::Input_section_list Input_section_list; |
| 878 | |
| 879 | // Create a stub group. |
| 880 | void create_stub_group(Input_section_list::const_iterator, |
| 881 | Input_section_list::const_iterator, |
| 882 | Input_section_list::const_iterator, |
| 883 | Target_arm<big_endian>*, |
| 884 | std::vector<Output_relaxed_input_section*>*); |
| 885 | }; |
| 886 | |
| 887 | // Arm_relobj class. |
| 888 | |
| 889 | template<bool big_endian> |
| 890 | class Arm_relobj : public Sized_relobj<32, big_endian> |
| 891 | { |
| 892 | public: |
| 893 | static const Arm_address invalid_address = static_cast<Arm_address>(-1); |
| 894 | |
| 895 | Arm_relobj(const std::string& name, Input_file* input_file, off_t offset, |
| 896 | const typename elfcpp::Ehdr<32, big_endian>& ehdr) |
| 897 | : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr), |
| 898 | stub_tables_(), local_symbol_is_thumb_function_() |
| 899 | { } |
| 900 | |
| 901 | ~Arm_relobj() |
| 902 | { } |
| 903 | |
| 904 | // Return the stub table of the SHNDX-th section if there is one. |
| 905 | Stub_table<big_endian>* |
| 906 | stub_table(unsigned int shndx) const |
| 907 | { |
| 908 | gold_assert(shndx < this->stub_tables_.size()); |
| 909 | return this->stub_tables_[shndx]; |
| 910 | } |
| 911 | |
| 912 | // Set STUB_TABLE to be the stub_table of the SHNDX-th section. |
| 913 | void |
| 914 | set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table) |
| 915 | { |
| 916 | gold_assert(shndx < this->stub_tables_.size()); |
| 917 | this->stub_tables_[shndx] = stub_table; |
| 918 | } |
| 919 | |
| 920 | // Whether a local symbol is a THUMB function. R_SYM is the symbol table |
| 921 | // index. This is only valid after do_count_local_symbol is called. |
| 922 | bool |
| 923 | local_symbol_is_thumb_function(unsigned int r_sym) const |
| 924 | { |
| 925 | gold_assert(r_sym < this->local_symbol_is_thumb_function_.size()); |
| 926 | return this->local_symbol_is_thumb_function_[r_sym]; |
| 927 | } |
| 928 | |
| 929 | // Scan all relocation sections for stub generation. |
| 930 | void |
| 931 | scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*, |
| 932 | const Layout*); |
| 933 | |
| 934 | // Convert regular input section with index SHNDX to a relaxed section. |
| 935 | void |
| 936 | convert_input_section_to_relaxed_section(unsigned shndx) |
| 937 | { |
| 938 | // The stubs have relocations and we need to process them after writing |
| 939 | // out the stubs. So relocation now must follow section write. |
| 940 | this->invalidate_section_offset(shndx); |
| 941 | this->set_relocs_must_follow_section_writes(); |
| 942 | } |
| 943 | |
| 944 | // Downcast a base pointer to an Arm_relobj pointer. This is |
| 945 | // not type-safe but we only use Arm_relobj not the base class. |
| 946 | static Arm_relobj<big_endian>* |
| 947 | as_arm_relobj(Relobj* relobj) |
| 948 | { return static_cast<Arm_relobj<big_endian>*>(relobj); } |
| 949 | |
| 950 | // Processor-specific flags in ELF file header. This is valid only after |
| 951 | // reading symbols. |
| 952 | elfcpp::Elf_Word |
| 953 | processor_specific_flags() const |
| 954 | { return this->processor_specific_flags_; } |
| 955 | |
| 956 | protected: |
| 957 | // Post constructor setup. |
| 958 | void |
| 959 | do_setup() |
| 960 | { |
| 961 | // Call parent's setup method. |
| 962 | Sized_relobj<32, big_endian>::do_setup(); |
| 963 | |
| 964 | // Initialize look-up tables. |
| 965 | Stub_table_list empty_stub_table_list(this->shnum(), NULL); |
| 966 | this->stub_tables_.swap(empty_stub_table_list); |
| 967 | } |
| 968 | |
| 969 | // Count the local symbols. |
| 970 | void |
| 971 | do_count_local_symbols(Stringpool_template<char>*, |
| 972 | Stringpool_template<char>*); |
| 973 | |
| 974 | void |
| 975 | do_relocate_sections(const Symbol_table* symtab, const Layout* layout, |
| 976 | const unsigned char* pshdrs, |
| 977 | typename Sized_relobj<32, big_endian>::Views* pivews); |
| 978 | |
| 979 | // Read the symbol information. |
| 980 | void |
| 981 | do_read_symbols(Read_symbols_data* sd); |
| 982 | |
| 983 | private: |
| 984 | // List of stub tables. |
| 985 | typedef std::vector<Stub_table<big_endian>*> Stub_table_list; |
| 986 | Stub_table_list stub_tables_; |
| 987 | // Bit vector to tell if a local symbol is a thumb function or not. |
| 988 | // This is only valid after do_count_local_symbol is called. |
| 989 | std::vector<bool> local_symbol_is_thumb_function_; |
| 990 | // processor-specific flags in ELF file header. |
| 991 | elfcpp::Elf_Word processor_specific_flags_; |
| 992 | }; |
| 993 | |
| 994 | // Arm_dynobj class. |
| 995 | |
| 996 | template<bool big_endian> |
| 997 | class Arm_dynobj : public Sized_dynobj<32, big_endian> |
| 998 | { |
| 999 | public: |
| 1000 | Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset, |
| 1001 | const elfcpp::Ehdr<32, big_endian>& ehdr) |
| 1002 | : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr), |
| 1003 | processor_specific_flags_(0) |
| 1004 | { } |
| 1005 | |
| 1006 | ~Arm_dynobj() |
| 1007 | { } |
| 1008 | |
| 1009 | // Downcast a base pointer to an Arm_relobj pointer. This is |
| 1010 | // not type-safe but we only use Arm_relobj not the base class. |
| 1011 | static Arm_dynobj<big_endian>* |
| 1012 | as_arm_dynobj(Dynobj* dynobj) |
| 1013 | { return static_cast<Arm_dynobj<big_endian>*>(dynobj); } |
| 1014 | |
| 1015 | // Processor-specific flags in ELF file header. This is valid only after |
| 1016 | // reading symbols. |
| 1017 | elfcpp::Elf_Word |
| 1018 | processor_specific_flags() const |
| 1019 | { return this->processor_specific_flags_; } |
| 1020 | |
| 1021 | protected: |
| 1022 | // Read the symbol information. |
| 1023 | void |
| 1024 | do_read_symbols(Read_symbols_data* sd); |
| 1025 | |
| 1026 | private: |
| 1027 | // processor-specific flags in ELF file header. |
| 1028 | elfcpp::Elf_Word processor_specific_flags_; |
| 1029 | }; |
| 1030 | |
| 1031 | // Functor to read reloc addends during stub generation. |
| 1032 | |
| 1033 | template<int sh_type, bool big_endian> |
| 1034 | struct Stub_addend_reader |
| 1035 | { |
| 1036 | // Return the addend for a relocation of a particular type. Depending |
| 1037 | // on whether this is a REL or RELA relocation, read the addend from a |
| 1038 | // view or from a Reloc object. |
| 1039 | elfcpp::Elf_types<32>::Elf_Swxword |
| 1040 | operator()( |
| 1041 | unsigned int /* r_type */, |
| 1042 | const unsigned char* /* view */, |
| 1043 | const typename Reloc_types<sh_type, |
| 1044 | 32, big_endian>::Reloc& /* reloc */) const; |
| 1045 | }; |
| 1046 | |
| 1047 | // Specialized Stub_addend_reader for SHT_REL type relocation sections. |
| 1048 | |
| 1049 | template<bool big_endian> |
| 1050 | struct Stub_addend_reader<elfcpp::SHT_REL, big_endian> |
| 1051 | { |
| 1052 | elfcpp::Elf_types<32>::Elf_Swxword |
| 1053 | operator()( |
| 1054 | unsigned int, |
| 1055 | const unsigned char*, |
| 1056 | const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const; |
| 1057 | }; |
| 1058 | |
| 1059 | // Specialized Stub_addend_reader for RELA type relocation sections. |
| 1060 | // We currently do not handle RELA type relocation sections but it is trivial |
| 1061 | // to implement the addend reader. This is provided for completeness and to |
| 1062 | // make it easier to add support for RELA relocation sections in the future. |
| 1063 | |
| 1064 | template<bool big_endian> |
| 1065 | struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian> |
| 1066 | { |
| 1067 | elfcpp::Elf_types<32>::Elf_Swxword |
| 1068 | operator()( |
| 1069 | unsigned int, |
| 1070 | const unsigned char*, |
| 1071 | const typename Reloc_types<elfcpp::SHT_RELA, 32, |
| 1072 | big_endian>::Reloc& reloc) const |
| 1073 | { return reloc.get_r_addend(); } |
| 1074 | }; |
| 1075 | |
| 1076 | // Utilities for manipulating integers of up to 32-bits |
| 1077 | |
| 1078 | namespace utils |
| 1079 | { |
| 1080 | // Sign extend an n-bit unsigned integer stored in an uint32_t into |
| 1081 | // an int32_t. NO_BITS must be between 1 to 32. |
| 1082 | template<int no_bits> |
| 1083 | static inline int32_t |
| 1084 | sign_extend(uint32_t bits) |
| 1085 | { |
| 1086 | gold_assert(no_bits >= 0 && no_bits <= 32); |
| 1087 | if (no_bits == 32) |
| 1088 | return static_cast<int32_t>(bits); |
| 1089 | uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits); |
| 1090 | bits &= mask; |
| 1091 | uint32_t top_bit = 1U << (no_bits - 1); |
| 1092 | int32_t as_signed = static_cast<int32_t>(bits); |
| 1093 | return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed; |
| 1094 | } |
| 1095 | |
| 1096 | // Detects overflow of an NO_BITS integer stored in a uint32_t. |
| 1097 | template<int no_bits> |
| 1098 | static inline bool |
| 1099 | has_overflow(uint32_t bits) |
| 1100 | { |
| 1101 | gold_assert(no_bits >= 0 && no_bits <= 32); |
| 1102 | if (no_bits == 32) |
| 1103 | return false; |
| 1104 | int32_t max = (1 << (no_bits - 1)) - 1; |
| 1105 | int32_t min = -(1 << (no_bits - 1)); |
| 1106 | int32_t as_signed = static_cast<int32_t>(bits); |
| 1107 | return as_signed > max || as_signed < min; |
| 1108 | } |
| 1109 | |
| 1110 | // Detects overflow of an NO_BITS integer stored in a uint32_t when it |
| 1111 | // fits in the given number of bits as either a signed or unsigned value. |
| 1112 | // For example, has_signed_unsigned_overflow<8> would check |
| 1113 | // -128 <= bits <= 255 |
| 1114 | template<int no_bits> |
| 1115 | static inline bool |
| 1116 | has_signed_unsigned_overflow(uint32_t bits) |
| 1117 | { |
| 1118 | gold_assert(no_bits >= 2 && no_bits <= 32); |
| 1119 | if (no_bits == 32) |
| 1120 | return false; |
| 1121 | int32_t max = static_cast<int32_t>((1U << no_bits) - 1); |
| 1122 | int32_t min = -(1 << (no_bits - 1)); |
| 1123 | int32_t as_signed = static_cast<int32_t>(bits); |
| 1124 | return as_signed > max || as_signed < min; |
| 1125 | } |
| 1126 | |
| 1127 | // Select bits from A and B using bits in MASK. For each n in [0..31], |
| 1128 | // the n-th bit in the result is chosen from the n-th bits of A and B. |
| 1129 | // A zero selects A and a one selects B. |
| 1130 | static inline uint32_t |
| 1131 | bit_select(uint32_t a, uint32_t b, uint32_t mask) |
| 1132 | { return (a & ~mask) | (b & mask); } |
| 1133 | }; |
| 1134 | |
| 1135 | template<bool big_endian> |
| 1136 | class Target_arm : public Sized_target<32, big_endian> |
| 1137 | { |
| 1138 | public: |
| 1139 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian> |
| 1140 | Reloc_section; |
| 1141 | |
| 1142 | // When were are relocating a stub, we pass this as the relocation number. |
| 1143 | static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1); |
| 1144 | |
| 1145 | Target_arm() |
| 1146 | : Sized_target<32, big_endian>(&arm_info), |
| 1147 | got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), |
| 1148 | copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL), stub_tables_(), |
| 1149 | stub_factory_(Stub_factory::get_instance()), |
| 1150 | may_use_blx_(true), should_force_pic_veneer_(false), |
| 1151 | arm_input_section_map_() |
| 1152 | { } |
| 1153 | |
| 1154 | // Whether we can use BLX. |
| 1155 | bool |
| 1156 | may_use_blx() const |
| 1157 | { return this->may_use_blx_; } |
| 1158 | |
| 1159 | // Set use-BLX flag. |
| 1160 | void |
| 1161 | set_may_use_blx(bool value) |
| 1162 | { this->may_use_blx_ = value; } |
| 1163 | |
| 1164 | // Whether we force PCI branch veneers. |
| 1165 | bool |
| 1166 | should_force_pic_veneer() const |
| 1167 | { return this->should_force_pic_veneer_; } |
| 1168 | |
| 1169 | // Set PIC veneer flag. |
| 1170 | void |
| 1171 | set_should_force_pic_veneer(bool value) |
| 1172 | { this->should_force_pic_veneer_ = value; } |
| 1173 | |
| 1174 | // Whether we use THUMB-2 instructions. |
| 1175 | bool |
| 1176 | using_thumb2() const |
| 1177 | { |
| 1178 | // FIXME: This should not hard-coded. |
| 1179 | return false; |
| 1180 | } |
| 1181 | |
| 1182 | // Whether we use THUMB/THUMB-2 instructions only. |
| 1183 | bool |
| 1184 | using_thumb_only() const |
| 1185 | { |
| 1186 | // FIXME: This should not hard-coded. |
| 1187 | return false; |
| 1188 | } |
| 1189 | |
| 1190 | // Process the relocations to determine unreferenced sections for |
| 1191 | // garbage collection. |
| 1192 | void |
| 1193 | gc_process_relocs(Symbol_table* symtab, |
| 1194 | Layout* layout, |
| 1195 | Sized_relobj<32, big_endian>* object, |
| 1196 | unsigned int data_shndx, |
| 1197 | unsigned int sh_type, |
| 1198 | const unsigned char* prelocs, |
| 1199 | size_t reloc_count, |
| 1200 | Output_section* output_section, |
| 1201 | bool needs_special_offset_handling, |
| 1202 | size_t local_symbol_count, |
| 1203 | const unsigned char* plocal_symbols); |
| 1204 | |
| 1205 | // Scan the relocations to look for symbol adjustments. |
| 1206 | void |
| 1207 | scan_relocs(Symbol_table* symtab, |
| 1208 | Layout* layout, |
| 1209 | Sized_relobj<32, big_endian>* object, |
| 1210 | unsigned int data_shndx, |
| 1211 | unsigned int sh_type, |
| 1212 | const unsigned char* prelocs, |
| 1213 | size_t reloc_count, |
| 1214 | Output_section* output_section, |
| 1215 | bool needs_special_offset_handling, |
| 1216 | size_t local_symbol_count, |
| 1217 | const unsigned char* plocal_symbols); |
| 1218 | |
| 1219 | // Finalize the sections. |
| 1220 | void |
| 1221 | do_finalize_sections(Layout*, const Input_objects*); |
| 1222 | |
| 1223 | // Return the value to use for a dynamic symbol which requires special |
| 1224 | // treatment. |
| 1225 | uint64_t |
| 1226 | do_dynsym_value(const Symbol*) const; |
| 1227 | |
| 1228 | // Relocate a section. |
| 1229 | void |
| 1230 | relocate_section(const Relocate_info<32, big_endian>*, |
| 1231 | unsigned int sh_type, |
| 1232 | const unsigned char* prelocs, |
| 1233 | size_t reloc_count, |
| 1234 | Output_section* output_section, |
| 1235 | bool needs_special_offset_handling, |
| 1236 | unsigned char* view, |
| 1237 | Arm_address view_address, |
| 1238 | section_size_type view_size, |
| 1239 | const Reloc_symbol_changes*); |
| 1240 | |
| 1241 | // Scan the relocs during a relocatable link. |
| 1242 | void |
| 1243 | scan_relocatable_relocs(Symbol_table* symtab, |
| 1244 | Layout* layout, |
| 1245 | Sized_relobj<32, big_endian>* object, |
| 1246 | unsigned int data_shndx, |
| 1247 | unsigned int sh_type, |
| 1248 | const unsigned char* prelocs, |
| 1249 | size_t reloc_count, |
| 1250 | Output_section* output_section, |
| 1251 | bool needs_special_offset_handling, |
| 1252 | size_t local_symbol_count, |
| 1253 | const unsigned char* plocal_symbols, |
| 1254 | Relocatable_relocs*); |
| 1255 | |
| 1256 | // Relocate a section during a relocatable link. |
| 1257 | void |
| 1258 | relocate_for_relocatable(const Relocate_info<32, big_endian>*, |
| 1259 | unsigned int sh_type, |
| 1260 | const unsigned char* prelocs, |
| 1261 | size_t reloc_count, |
| 1262 | Output_section* output_section, |
| 1263 | off_t offset_in_output_section, |
| 1264 | const Relocatable_relocs*, |
| 1265 | unsigned char* view, |
| 1266 | Arm_address view_address, |
| 1267 | section_size_type view_size, |
| 1268 | unsigned char* reloc_view, |
| 1269 | section_size_type reloc_view_size); |
| 1270 | |
| 1271 | // Return whether SYM is defined by the ABI. |
| 1272 | bool |
| 1273 | do_is_defined_by_abi(Symbol* sym) const |
| 1274 | { return strcmp(sym->name(), "__tls_get_addr") == 0; } |
| 1275 | |
| 1276 | // Return the size of the GOT section. |
| 1277 | section_size_type |
| 1278 | got_size() |
| 1279 | { |
| 1280 | gold_assert(this->got_ != NULL); |
| 1281 | return this->got_->data_size(); |
| 1282 | } |
| 1283 | |
| 1284 | // Map platform-specific reloc types |
| 1285 | static unsigned int |
| 1286 | get_real_reloc_type (unsigned int r_type); |
| 1287 | |
| 1288 | // |
| 1289 | // Methods to support stub-generations. |
| 1290 | // |
| 1291 | |
| 1292 | // Return the stub factory |
| 1293 | const Stub_factory& |
| 1294 | stub_factory() const |
| 1295 | { return this->stub_factory_; } |
| 1296 | |
| 1297 | // Make a new Arm_input_section object. |
| 1298 | Arm_input_section<big_endian>* |
| 1299 | new_arm_input_section(Relobj*, unsigned int); |
| 1300 | |
| 1301 | // Find the Arm_input_section object corresponding to the SHNDX-th input |
| 1302 | // section of RELOBJ. |
| 1303 | Arm_input_section<big_endian>* |
| 1304 | find_arm_input_section(Relobj* relobj, unsigned int shndx) const; |
| 1305 | |
| 1306 | // Make a new Stub_table |
| 1307 | Stub_table<big_endian>* |
| 1308 | new_stub_table(Arm_input_section<big_endian>*); |
| 1309 | |
| 1310 | // Scan a section for stub generation. |
| 1311 | void |
| 1312 | scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int, |
| 1313 | const unsigned char*, size_t, Output_section*, |
| 1314 | bool, const unsigned char*, Arm_address, |
| 1315 | section_size_type); |
| 1316 | |
| 1317 | // Relocate a stub. |
| 1318 | void |
| 1319 | relocate_stub(Reloc_stub*, const Relocate_info<32, big_endian>*, |
| 1320 | Output_section*, unsigned char*, Arm_address, |
| 1321 | section_size_type); |
| 1322 | |
| 1323 | // Get the default ARM target. |
| 1324 | static Target_arm<big_endian>* |
| 1325 | default_target() |
| 1326 | { |
| 1327 | gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM |
| 1328 | && parameters->target().is_big_endian() == big_endian); |
| 1329 | return static_cast<Target_arm<big_endian>*>( |
| 1330 | parameters->sized_target<32, big_endian>()); |
| 1331 | } |
| 1332 | |
| 1333 | // Whether relocation type uses LSB to distinguish THUMB addresses. |
| 1334 | static bool |
| 1335 | reloc_uses_thumb_bit(unsigned int r_type); |
| 1336 | |
| 1337 | protected: |
| 1338 | // Make an ELF object. |
| 1339 | Object* |
| 1340 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1341 | const elfcpp::Ehdr<32, big_endian>& ehdr); |
| 1342 | |
| 1343 | Object* |
| 1344 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1345 | const elfcpp::Ehdr<32, !big_endian>&) |
| 1346 | { gold_unreachable(); } |
| 1347 | |
| 1348 | Object* |
| 1349 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1350 | const elfcpp::Ehdr<64, false>&) |
| 1351 | { gold_unreachable(); } |
| 1352 | |
| 1353 | Object* |
| 1354 | do_make_elf_object(const std::string&, Input_file*, off_t, |
| 1355 | const elfcpp::Ehdr<64, true>&) |
| 1356 | { gold_unreachable(); } |
| 1357 | |
| 1358 | // Make an output section. |
| 1359 | Output_section* |
| 1360 | do_make_output_section(const char* name, elfcpp::Elf_Word type, |
| 1361 | elfcpp::Elf_Xword flags) |
| 1362 | { return new Arm_output_section<big_endian>(name, type, flags); } |
| 1363 | |
| 1364 | void |
| 1365 | do_adjust_elf_header(unsigned char* view, int len) const; |
| 1366 | |
| 1367 | // We only need to generate stubs, and hence perform relaxation if we are |
| 1368 | // not doing relocatable linking. |
| 1369 | bool |
| 1370 | do_may_relax() const |
| 1371 | { return !parameters->options().relocatable(); } |
| 1372 | |
| 1373 | bool |
| 1374 | do_relax(int, const Input_objects*, Symbol_table*, Layout*); |
| 1375 | |
| 1376 | private: |
| 1377 | // The class which scans relocations. |
| 1378 | class Scan |
| 1379 | { |
| 1380 | public: |
| 1381 | Scan() |
| 1382 | : issued_non_pic_error_(false) |
| 1383 | { } |
| 1384 | |
| 1385 | inline void |
| 1386 | local(Symbol_table* symtab, Layout* layout, Target_arm* target, |
| 1387 | Sized_relobj<32, big_endian>* object, |
| 1388 | unsigned int data_shndx, |
| 1389 | Output_section* output_section, |
| 1390 | const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type, |
| 1391 | const elfcpp::Sym<32, big_endian>& lsym); |
| 1392 | |
| 1393 | inline void |
| 1394 | global(Symbol_table* symtab, Layout* layout, Target_arm* target, |
| 1395 | Sized_relobj<32, big_endian>* object, |
| 1396 | unsigned int data_shndx, |
| 1397 | Output_section* output_section, |
| 1398 | const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type, |
| 1399 | Symbol* gsym); |
| 1400 | |
| 1401 | private: |
| 1402 | static void |
| 1403 | unsupported_reloc_local(Sized_relobj<32, big_endian>*, |
| 1404 | unsigned int r_type); |
| 1405 | |
| 1406 | static void |
| 1407 | unsupported_reloc_global(Sized_relobj<32, big_endian>*, |
| 1408 | unsigned int r_type, Symbol*); |
| 1409 | |
| 1410 | void |
| 1411 | check_non_pic(Relobj*, unsigned int r_type); |
| 1412 | |
| 1413 | // Almost identical to Symbol::needs_plt_entry except that it also |
| 1414 | // handles STT_ARM_TFUNC. |
| 1415 | static bool |
| 1416 | symbol_needs_plt_entry(const Symbol* sym) |
| 1417 | { |
| 1418 | // An undefined symbol from an executable does not need a PLT entry. |
| 1419 | if (sym->is_undefined() && !parameters->options().shared()) |
| 1420 | return false; |
| 1421 | |
| 1422 | return (!parameters->doing_static_link() |
| 1423 | && (sym->type() == elfcpp::STT_FUNC |
| 1424 | || sym->type() == elfcpp::STT_ARM_TFUNC) |
| 1425 | && (sym->is_from_dynobj() |
| 1426 | || sym->is_undefined() |
| 1427 | || sym->is_preemptible())); |
| 1428 | } |
| 1429 | |
| 1430 | // Whether we have issued an error about a non-PIC compilation. |
| 1431 | bool issued_non_pic_error_; |
| 1432 | }; |
| 1433 | |
| 1434 | // The class which implements relocation. |
| 1435 | class Relocate |
| 1436 | { |
| 1437 | public: |
| 1438 | Relocate() |
| 1439 | { } |
| 1440 | |
| 1441 | ~Relocate() |
| 1442 | { } |
| 1443 | |
| 1444 | // Return whether the static relocation needs to be applied. |
| 1445 | inline bool |
| 1446 | should_apply_static_reloc(const Sized_symbol<32>* gsym, |
| 1447 | int ref_flags, |
| 1448 | bool is_32bit, |
| 1449 | Output_section* output_section); |
| 1450 | |
| 1451 | // Do a relocation. Return false if the caller should not issue |
| 1452 | // any warnings about this relocation. |
| 1453 | inline bool |
| 1454 | relocate(const Relocate_info<32, big_endian>*, Target_arm*, |
| 1455 | Output_section*, size_t relnum, |
| 1456 | const elfcpp::Rel<32, big_endian>&, |
| 1457 | unsigned int r_type, const Sized_symbol<32>*, |
| 1458 | const Symbol_value<32>*, |
| 1459 | unsigned char*, Arm_address, |
| 1460 | section_size_type); |
| 1461 | |
| 1462 | // Return whether we want to pass flag NON_PIC_REF for this |
| 1463 | // reloc. |
| 1464 | static inline bool |
| 1465 | reloc_is_non_pic (unsigned int r_type) |
| 1466 | { |
| 1467 | switch (r_type) |
| 1468 | { |
| 1469 | case elfcpp::R_ARM_REL32: |
| 1470 | case elfcpp::R_ARM_THM_CALL: |
| 1471 | case elfcpp::R_ARM_CALL: |
| 1472 | case elfcpp::R_ARM_JUMP24: |
| 1473 | case elfcpp::R_ARM_PREL31: |
| 1474 | case elfcpp::R_ARM_THM_ABS5: |
| 1475 | case elfcpp::R_ARM_ABS8: |
| 1476 | case elfcpp::R_ARM_ABS12: |
| 1477 | case elfcpp::R_ARM_ABS16: |
| 1478 | case elfcpp::R_ARM_BASE_ABS: |
| 1479 | return true; |
| 1480 | default: |
| 1481 | return false; |
| 1482 | } |
| 1483 | } |
| 1484 | }; |
| 1485 | |
| 1486 | // A class which returns the size required for a relocation type, |
| 1487 | // used while scanning relocs during a relocatable link. |
| 1488 | class Relocatable_size_for_reloc |
| 1489 | { |
| 1490 | public: |
| 1491 | unsigned int |
| 1492 | get_size_for_reloc(unsigned int, Relobj*); |
| 1493 | }; |
| 1494 | |
| 1495 | // Get the GOT section, creating it if necessary. |
| 1496 | Output_data_got<32, big_endian>* |
| 1497 | got_section(Symbol_table*, Layout*); |
| 1498 | |
| 1499 | // Get the GOT PLT section. |
| 1500 | Output_data_space* |
| 1501 | got_plt_section() const |
| 1502 | { |
| 1503 | gold_assert(this->got_plt_ != NULL); |
| 1504 | return this->got_plt_; |
| 1505 | } |
| 1506 | |
| 1507 | // Create a PLT entry for a global symbol. |
| 1508 | void |
| 1509 | make_plt_entry(Symbol_table*, Layout*, Symbol*); |
| 1510 | |
| 1511 | // Get the PLT section. |
| 1512 | const Output_data_plt_arm<big_endian>* |
| 1513 | plt_section() const |
| 1514 | { |
| 1515 | gold_assert(this->plt_ != NULL); |
| 1516 | return this->plt_; |
| 1517 | } |
| 1518 | |
| 1519 | // Get the dynamic reloc section, creating it if necessary. |
| 1520 | Reloc_section* |
| 1521 | rel_dyn_section(Layout*); |
| 1522 | |
| 1523 | // Return true if the symbol may need a COPY relocation. |
| 1524 | // References from an executable object to non-function symbols |
| 1525 | // defined in a dynamic object may need a COPY relocation. |
| 1526 | bool |
| 1527 | may_need_copy_reloc(Symbol* gsym) |
| 1528 | { |
| 1529 | return (gsym->type() != elfcpp::STT_ARM_TFUNC |
| 1530 | && gsym->may_need_copy_reloc()); |
| 1531 | } |
| 1532 | |
| 1533 | // Add a potential copy relocation. |
| 1534 | void |
| 1535 | copy_reloc(Symbol_table* symtab, Layout* layout, |
| 1536 | Sized_relobj<32, big_endian>* object, |
| 1537 | unsigned int shndx, Output_section* output_section, |
| 1538 | Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc) |
| 1539 | { |
| 1540 | this->copy_relocs_.copy_reloc(symtab, layout, |
| 1541 | symtab->get_sized_symbol<32>(sym), |
| 1542 | object, shndx, output_section, reloc, |
| 1543 | this->rel_dyn_section(layout)); |
| 1544 | } |
| 1545 | |
| 1546 | // Whether two EABI versions are compatible. |
| 1547 | static bool |
| 1548 | are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2); |
| 1549 | |
| 1550 | // Merge processor-specific flags from input object and those in the ELF |
| 1551 | // header of the output. |
| 1552 | void |
| 1553 | merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word); |
| 1554 | |
| 1555 | // |
| 1556 | // Methods to support stub-generations. |
| 1557 | // |
| 1558 | |
| 1559 | // Group input sections for stub generation. |
| 1560 | void |
| 1561 | group_sections(Layout*, section_size_type, bool); |
| 1562 | |
| 1563 | // Scan a relocation for stub generation. |
| 1564 | void |
| 1565 | scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int, |
| 1566 | const Sized_symbol<32>*, unsigned int, |
| 1567 | const Symbol_value<32>*, |
| 1568 | elfcpp::Elf_types<32>::Elf_Swxword, Arm_address); |
| 1569 | |
| 1570 | // Scan a relocation section for stub. |
| 1571 | template<int sh_type> |
| 1572 | void |
| 1573 | scan_reloc_section_for_stubs( |
| 1574 | const Relocate_info<32, big_endian>* relinfo, |
| 1575 | const unsigned char* prelocs, |
| 1576 | size_t reloc_count, |
| 1577 | Output_section* output_section, |
| 1578 | bool needs_special_offset_handling, |
| 1579 | const unsigned char* view, |
| 1580 | elfcpp::Elf_types<32>::Elf_Addr view_address, |
| 1581 | section_size_type); |
| 1582 | |
| 1583 | // Information about this specific target which we pass to the |
| 1584 | // general Target structure. |
| 1585 | static const Target::Target_info arm_info; |
| 1586 | |
| 1587 | // The types of GOT entries needed for this platform. |
| 1588 | enum Got_type |
| 1589 | { |
| 1590 | GOT_TYPE_STANDARD = 0 // GOT entry for a regular symbol |
| 1591 | }; |
| 1592 | |
| 1593 | typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list; |
| 1594 | |
| 1595 | // Map input section to Arm_input_section. |
| 1596 | typedef Unordered_map<Input_section_specifier, |
| 1597 | Arm_input_section<big_endian>*, |
| 1598 | Input_section_specifier::hash, |
| 1599 | Input_section_specifier::equal_to> |
| 1600 | Arm_input_section_map; |
| 1601 | |
| 1602 | // The GOT section. |
| 1603 | Output_data_got<32, big_endian>* got_; |
| 1604 | // The PLT section. |
| 1605 | Output_data_plt_arm<big_endian>* plt_; |
| 1606 | // The GOT PLT section. |
| 1607 | Output_data_space* got_plt_; |
| 1608 | // The dynamic reloc section. |
| 1609 | Reloc_section* rel_dyn_; |
| 1610 | // Relocs saved to avoid a COPY reloc. |
| 1611 | Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_; |
| 1612 | // Space for variables copied with a COPY reloc. |
| 1613 | Output_data_space* dynbss_; |
| 1614 | // Vector of Stub_tables created. |
| 1615 | Stub_table_list stub_tables_; |
| 1616 | // Stub factory. |
| 1617 | const Stub_factory &stub_factory_; |
| 1618 | // Whether we can use BLX. |
| 1619 | bool may_use_blx_; |
| 1620 | // Whether we force PIC branch veneers. |
| 1621 | bool should_force_pic_veneer_; |
| 1622 | // Map for locating Arm_input_sections. |
| 1623 | Arm_input_section_map arm_input_section_map_; |
| 1624 | }; |
| 1625 | |
| 1626 | template<bool big_endian> |
| 1627 | const Target::Target_info Target_arm<big_endian>::arm_info = |
| 1628 | { |
| 1629 | 32, // size |
| 1630 | big_endian, // is_big_endian |
| 1631 | elfcpp::EM_ARM, // machine_code |
| 1632 | false, // has_make_symbol |
| 1633 | false, // has_resolve |
| 1634 | false, // has_code_fill |
| 1635 | true, // is_default_stack_executable |
| 1636 | '\0', // wrap_char |
| 1637 | "/usr/lib/libc.so.1", // dynamic_linker |
| 1638 | 0x8000, // default_text_segment_address |
| 1639 | 0x1000, // abi_pagesize (overridable by -z max-page-size) |
| 1640 | 0x1000, // common_pagesize (overridable by -z common-page-size) |
| 1641 | elfcpp::SHN_UNDEF, // small_common_shndx |
| 1642 | elfcpp::SHN_UNDEF, // large_common_shndx |
| 1643 | 0, // small_common_section_flags |
| 1644 | 0 // large_common_section_flags |
| 1645 | }; |
| 1646 | |
| 1647 | // Arm relocate functions class |
| 1648 | // |
| 1649 | |
| 1650 | template<bool big_endian> |
| 1651 | class Arm_relocate_functions : public Relocate_functions<32, big_endian> |
| 1652 | { |
| 1653 | public: |
| 1654 | typedef enum |
| 1655 | { |
| 1656 | STATUS_OKAY, // No error during relocation. |
| 1657 | STATUS_OVERFLOW, // Relocation oveflow. |
| 1658 | STATUS_BAD_RELOC // Relocation cannot be applied. |
| 1659 | } Status; |
| 1660 | |
| 1661 | private: |
| 1662 | typedef Relocate_functions<32, big_endian> Base; |
| 1663 | typedef Arm_relocate_functions<big_endian> This; |
| 1664 | |
| 1665 | // Encoding of imm16 argument for movt and movw ARM instructions |
| 1666 | // from ARM ARM: |
| 1667 | // |
| 1668 | // imm16 := imm4 | imm12 |
| 1669 | // |
| 1670 | // 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 |
| 1671 | // +-------+---------------+-------+-------+-----------------------+ |
| 1672 | // | | |imm4 | |imm12 | |
| 1673 | // +-------+---------------+-------+-------+-----------------------+ |
| 1674 | |
| 1675 | // Extract the relocation addend from VAL based on the ARM |
| 1676 | // instruction encoding described above. |
| 1677 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 1678 | extract_arm_movw_movt_addend( |
| 1679 | typename elfcpp::Swap<32, big_endian>::Valtype val) |
| 1680 | { |
| 1681 | // According to the Elf ABI for ARM Architecture the immediate |
| 1682 | // field is sign-extended to form the addend. |
| 1683 | return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff)); |
| 1684 | } |
| 1685 | |
| 1686 | // Insert X into VAL based on the ARM instruction encoding described |
| 1687 | // above. |
| 1688 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 1689 | insert_val_arm_movw_movt( |
| 1690 | typename elfcpp::Swap<32, big_endian>::Valtype val, |
| 1691 | typename elfcpp::Swap<32, big_endian>::Valtype x) |
| 1692 | { |
| 1693 | val &= 0xfff0f000; |
| 1694 | val |= x & 0x0fff; |
| 1695 | val |= (x & 0xf000) << 4; |
| 1696 | return val; |
| 1697 | } |
| 1698 | |
| 1699 | // Encoding of imm16 argument for movt and movw Thumb2 instructions |
| 1700 | // from ARM ARM: |
| 1701 | // |
| 1702 | // imm16 := imm4 | i | imm3 | imm8 |
| 1703 | // |
| 1704 | // 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 |
| 1705 | // +---------+-+-----------+-------++-+-----+-------+---------------+ |
| 1706 | // | |i| |imm4 || |imm3 | |imm8 | |
| 1707 | // +---------+-+-----------+-------++-+-----+-------+---------------+ |
| 1708 | |
| 1709 | // Extract the relocation addend from VAL based on the Thumb2 |
| 1710 | // instruction encoding described above. |
| 1711 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 1712 | extract_thumb_movw_movt_addend( |
| 1713 | typename elfcpp::Swap<32, big_endian>::Valtype val) |
| 1714 | { |
| 1715 | // According to the Elf ABI for ARM Architecture the immediate |
| 1716 | // field is sign-extended to form the addend. |
| 1717 | return utils::sign_extend<16>(((val >> 4) & 0xf000) |
| 1718 | | ((val >> 15) & 0x0800) |
| 1719 | | ((val >> 4) & 0x0700) |
| 1720 | | (val & 0x00ff)); |
| 1721 | } |
| 1722 | |
| 1723 | // Insert X into VAL based on the Thumb2 instruction encoding |
| 1724 | // described above. |
| 1725 | static inline typename elfcpp::Swap<32, big_endian>::Valtype |
| 1726 | insert_val_thumb_movw_movt( |
| 1727 | typename elfcpp::Swap<32, big_endian>::Valtype val, |
| 1728 | typename elfcpp::Swap<32, big_endian>::Valtype x) |
| 1729 | { |
| 1730 | val &= 0xfbf08f00; |
| 1731 | val |= (x & 0xf000) << 4; |
| 1732 | val |= (x & 0x0800) << 15; |
| 1733 | val |= (x & 0x0700) << 4; |
| 1734 | val |= (x & 0x00ff); |
| 1735 | return val; |
| 1736 | } |
| 1737 | |
| 1738 | // FIXME: This probably only works for Android on ARM v5te. We should |
| 1739 | // following GNU ld for the general case. |
| 1740 | template<unsigned r_type> |
| 1741 | static inline typename This::Status |
| 1742 | arm_branch_common(unsigned char *view, |
| 1743 | const Sized_relobj<32, big_endian>* object, |
| 1744 | const Symbol_value<32>* psymval, |
| 1745 | Arm_address address, |
| 1746 | Arm_address thumb_bit) |
| 1747 | { |
| 1748 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 1749 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1750 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 1751 | |
| 1752 | bool insn_is_b = (((val >> 28) & 0xf) <= 0xe) |
| 1753 | && ((val & 0x0f000000UL) == 0x0a000000UL); |
| 1754 | bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL; |
| 1755 | bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe) |
| 1756 | && ((val & 0x0f000000UL) == 0x0b000000UL); |
| 1757 | bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL; |
| 1758 | bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL; |
| 1759 | |
| 1760 | if (r_type == elfcpp::R_ARM_CALL) |
| 1761 | { |
| 1762 | if (!insn_is_uncond_bl && !insn_is_blx) |
| 1763 | return This::STATUS_BAD_RELOC; |
| 1764 | } |
| 1765 | else if (r_type == elfcpp::R_ARM_JUMP24) |
| 1766 | { |
| 1767 | if (!insn_is_b && !insn_is_cond_bl) |
| 1768 | return This::STATUS_BAD_RELOC; |
| 1769 | } |
| 1770 | else if (r_type == elfcpp::R_ARM_PLT32) |
| 1771 | { |
| 1772 | if (!insn_is_any_branch) |
| 1773 | return This::STATUS_BAD_RELOC; |
| 1774 | } |
| 1775 | else |
| 1776 | gold_unreachable(); |
| 1777 | |
| 1778 | Valtype addend = utils::sign_extend<26>(val << 2); |
| 1779 | Valtype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 1780 | |
| 1781 | // If target has thumb bit set, we need to either turn the BL |
| 1782 | // into a BLX (for ARMv5 or above) or generate a stub. |
| 1783 | if (x & 1) |
| 1784 | { |
| 1785 | // Turn BL to BLX. |
| 1786 | if (insn_is_uncond_bl) |
| 1787 | val = (val & 0xffffff) | 0xfa000000 | ((x & 2) << 23); |
| 1788 | else |
| 1789 | return This::STATUS_BAD_RELOC; |
| 1790 | } |
| 1791 | else |
| 1792 | gold_assert(!insn_is_blx); |
| 1793 | |
| 1794 | val = utils::bit_select(val, (x >> 2), 0xffffffUL); |
| 1795 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 1796 | return (utils::has_overflow<26>(x) |
| 1797 | ? This::STATUS_OVERFLOW : This::STATUS_OKAY); |
| 1798 | } |
| 1799 | |
| 1800 | public: |
| 1801 | |
| 1802 | // R_ARM_ABS8: S + A |
| 1803 | static inline typename This::Status |
| 1804 | abs8(unsigned char *view, |
| 1805 | const Sized_relobj<32, big_endian>* object, |
| 1806 | const Symbol_value<32>* psymval) |
| 1807 | { |
| 1808 | typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype; |
| 1809 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 1810 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1811 | Valtype val = elfcpp::Swap<8, big_endian>::readval(wv); |
| 1812 | Reltype addend = utils::sign_extend<8>(val); |
| 1813 | Reltype x = psymval->value(object, addend); |
| 1814 | val = utils::bit_select(val, x, 0xffU); |
| 1815 | elfcpp::Swap<8, big_endian>::writeval(wv, val); |
| 1816 | return (utils::has_signed_unsigned_overflow<8>(x) |
| 1817 | ? This::STATUS_OVERFLOW |
| 1818 | : This::STATUS_OKAY); |
| 1819 | } |
| 1820 | |
| 1821 | // R_ARM_THM_ABS5: S + A |
| 1822 | static inline typename This::Status |
| 1823 | thm_abs5(unsigned char *view, |
| 1824 | const Sized_relobj<32, big_endian>* object, |
| 1825 | const Symbol_value<32>* psymval) |
| 1826 | { |
| 1827 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 1828 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 1829 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1830 | Valtype val = elfcpp::Swap<16, big_endian>::readval(wv); |
| 1831 | Reltype addend = (val & 0x7e0U) >> 6; |
| 1832 | Reltype x = psymval->value(object, addend); |
| 1833 | val = utils::bit_select(val, x << 6, 0x7e0U); |
| 1834 | elfcpp::Swap<16, big_endian>::writeval(wv, val); |
| 1835 | return (utils::has_overflow<5>(x) |
| 1836 | ? This::STATUS_OVERFLOW |
| 1837 | : This::STATUS_OKAY); |
| 1838 | } |
| 1839 | |
| 1840 | // R_ARM_ABS12: S + A |
| 1841 | static inline typename This::Status |
| 1842 | abs12(unsigned char *view, |
| 1843 | const Sized_relobj<32, big_endian>* object, |
| 1844 | const Symbol_value<32>* psymval) |
| 1845 | { |
| 1846 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 1847 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 1848 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1849 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 1850 | Reltype addend = val & 0x0fffU; |
| 1851 | Reltype x = psymval->value(object, addend); |
| 1852 | val = utils::bit_select(val, x, 0x0fffU); |
| 1853 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 1854 | return (utils::has_overflow<12>(x) |
| 1855 | ? This::STATUS_OVERFLOW |
| 1856 | : This::STATUS_OKAY); |
| 1857 | } |
| 1858 | |
| 1859 | // R_ARM_ABS16: S + A |
| 1860 | static inline typename This::Status |
| 1861 | abs16(unsigned char *view, |
| 1862 | const Sized_relobj<32, big_endian>* object, |
| 1863 | const Symbol_value<32>* psymval) |
| 1864 | { |
| 1865 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 1866 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 1867 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1868 | Valtype val = elfcpp::Swap<16, big_endian>::readval(wv); |
| 1869 | Reltype addend = utils::sign_extend<16>(val); |
| 1870 | Reltype x = psymval->value(object, addend); |
| 1871 | val = utils::bit_select(val, x, 0xffffU); |
| 1872 | elfcpp::Swap<16, big_endian>::writeval(wv, val); |
| 1873 | return (utils::has_signed_unsigned_overflow<16>(x) |
| 1874 | ? This::STATUS_OVERFLOW |
| 1875 | : This::STATUS_OKAY); |
| 1876 | } |
| 1877 | |
| 1878 | // R_ARM_ABS32: (S + A) | T |
| 1879 | static inline typename This::Status |
| 1880 | abs32(unsigned char *view, |
| 1881 | const Sized_relobj<32, big_endian>* object, |
| 1882 | const Symbol_value<32>* psymval, |
| 1883 | Arm_address thumb_bit) |
| 1884 | { |
| 1885 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 1886 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1887 | Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv); |
| 1888 | Valtype x = psymval->value(object, addend) | thumb_bit; |
| 1889 | elfcpp::Swap<32, big_endian>::writeval(wv, x); |
| 1890 | return This::STATUS_OKAY; |
| 1891 | } |
| 1892 | |
| 1893 | // R_ARM_REL32: (S + A) | T - P |
| 1894 | static inline typename This::Status |
| 1895 | rel32(unsigned char *view, |
| 1896 | const Sized_relobj<32, big_endian>* object, |
| 1897 | const Symbol_value<32>* psymval, |
| 1898 | Arm_address address, |
| 1899 | Arm_address thumb_bit) |
| 1900 | { |
| 1901 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 1902 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1903 | Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv); |
| 1904 | Valtype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 1905 | elfcpp::Swap<32, big_endian>::writeval(wv, x); |
| 1906 | return This::STATUS_OKAY; |
| 1907 | } |
| 1908 | |
| 1909 | // R_ARM_THM_CALL: (S + A) | T - P |
| 1910 | static inline typename This::Status |
| 1911 | thm_call(unsigned char *view, |
| 1912 | const Sized_relobj<32, big_endian>* object, |
| 1913 | const Symbol_value<32>* psymval, |
| 1914 | Arm_address address, |
| 1915 | Arm_address thumb_bit) |
| 1916 | { |
| 1917 | // A thumb call consists of two instructions. |
| 1918 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 1919 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 1920 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 1921 | Valtype hi = elfcpp::Swap<16, big_endian>::readval(wv); |
| 1922 | Valtype lo = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 1923 | // Must be a BL instruction. lo == 11111xxxxxxxxxxx. |
| 1924 | gold_assert((lo & 0xf800) == 0xf800); |
| 1925 | Reltype addend = utils::sign_extend<23>(((hi & 0x7ff) << 12) |
| 1926 | | ((lo & 0x7ff) << 1)); |
| 1927 | Reltype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 1928 | |
| 1929 | // If target has no thumb bit set, we need to either turn the BL |
| 1930 | // into a BLX (for ARMv5 or above) or generate a stub. |
| 1931 | if ((x & 1) == 0) |
| 1932 | { |
| 1933 | // This only works for ARMv5 and above with interworking enabled. |
| 1934 | lo &= 0xefff; |
| 1935 | } |
| 1936 | hi = utils::bit_select(hi, (x >> 12), 0x7ffU); |
| 1937 | lo = utils::bit_select(lo, (x >> 1), 0x7ffU); |
| 1938 | elfcpp::Swap<16, big_endian>::writeval(wv, hi); |
| 1939 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, lo); |
| 1940 | return (utils::has_overflow<23>(x) |
| 1941 | ? This::STATUS_OVERFLOW |
| 1942 | : This::STATUS_OKAY); |
| 1943 | } |
| 1944 | |
| 1945 | // R_ARM_BASE_PREL: B(S) + A - P |
| 1946 | static inline typename This::Status |
| 1947 | base_prel(unsigned char* view, |
| 1948 | Arm_address origin, |
| 1949 | Arm_address address) |
| 1950 | { |
| 1951 | Base::rel32(view, origin - address); |
| 1952 | return STATUS_OKAY; |
| 1953 | } |
| 1954 | |
| 1955 | // R_ARM_BASE_ABS: B(S) + A |
| 1956 | static inline typename This::Status |
| 1957 | base_abs(unsigned char* view, |
| 1958 | Arm_address origin) |
| 1959 | { |
| 1960 | Base::rel32(view, origin); |
| 1961 | return STATUS_OKAY; |
| 1962 | } |
| 1963 | |
| 1964 | // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG |
| 1965 | static inline typename This::Status |
| 1966 | got_brel(unsigned char* view, |
| 1967 | typename elfcpp::Swap<32, big_endian>::Valtype got_offset) |
| 1968 | { |
| 1969 | Base::rel32(view, got_offset); |
| 1970 | return This::STATUS_OKAY; |
| 1971 | } |
| 1972 | |
| 1973 | // R_ARM_GOT_PREL: GOT(S) + A – P |
| 1974 | static inline typename This::Status |
| 1975 | got_prel(unsigned char* view, |
| 1976 | typename elfcpp::Swap<32, big_endian>::Valtype got_offset, |
| 1977 | Arm_address address) |
| 1978 | { |
| 1979 | Base::rel32(view, got_offset - address); |
| 1980 | return This::STATUS_OKAY; |
| 1981 | } |
| 1982 | |
| 1983 | // R_ARM_PLT32: (S + A) | T - P |
| 1984 | static inline typename This::Status |
| 1985 | plt32(unsigned char *view, |
| 1986 | const Sized_relobj<32, big_endian>* object, |
| 1987 | const Symbol_value<32>* psymval, |
| 1988 | Arm_address address, |
| 1989 | Arm_address thumb_bit) |
| 1990 | { |
| 1991 | return arm_branch_common<elfcpp::R_ARM_PLT32>(view, object, psymval, |
| 1992 | address, thumb_bit); |
| 1993 | } |
| 1994 | |
| 1995 | // R_ARM_CALL: (S + A) | T - P |
| 1996 | static inline typename This::Status |
| 1997 | call(unsigned char *view, |
| 1998 | const Sized_relobj<32, big_endian>* object, |
| 1999 | const Symbol_value<32>* psymval, |
| 2000 | Arm_address address, |
| 2001 | Arm_address thumb_bit) |
| 2002 | { |
| 2003 | return arm_branch_common<elfcpp::R_ARM_CALL>(view, object, psymval, |
| 2004 | address, thumb_bit); |
| 2005 | } |
| 2006 | |
| 2007 | // R_ARM_JUMP24: (S + A) | T - P |
| 2008 | static inline typename This::Status |
| 2009 | jump24(unsigned char *view, |
| 2010 | const Sized_relobj<32, big_endian>* object, |
| 2011 | const Symbol_value<32>* psymval, |
| 2012 | Arm_address address, |
| 2013 | Arm_address thumb_bit) |
| 2014 | { |
| 2015 | return arm_branch_common<elfcpp::R_ARM_JUMP24>(view, object, psymval, |
| 2016 | address, thumb_bit); |
| 2017 | } |
| 2018 | |
| 2019 | // R_ARM_PREL: (S + A) | T - P |
| 2020 | static inline typename This::Status |
| 2021 | prel31(unsigned char *view, |
| 2022 | const Sized_relobj<32, big_endian>* object, |
| 2023 | const Symbol_value<32>* psymval, |
| 2024 | Arm_address address, |
| 2025 | Arm_address thumb_bit) |
| 2026 | { |
| 2027 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2028 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2029 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2030 | Valtype addend = utils::sign_extend<31>(val); |
| 2031 | Valtype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 2032 | val = utils::bit_select(val, x, 0x7fffffffU); |
| 2033 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2034 | return (utils::has_overflow<31>(x) ? |
| 2035 | This::STATUS_OVERFLOW : This::STATUS_OKAY); |
| 2036 | } |
| 2037 | |
| 2038 | // R_ARM_MOVW_ABS_NC: (S + A) | T |
| 2039 | static inline typename This::Status |
| 2040 | movw_abs_nc(unsigned char *view, |
| 2041 | const Sized_relobj<32, big_endian>* object, |
| 2042 | const Symbol_value<32>* psymval, |
| 2043 | Arm_address thumb_bit) |
| 2044 | { |
| 2045 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2046 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2047 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2048 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2049 | Valtype x = psymval->value(object, addend) | thumb_bit; |
| 2050 | val = This::insert_val_arm_movw_movt(val, x); |
| 2051 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2052 | return This::STATUS_OKAY; |
| 2053 | } |
| 2054 | |
| 2055 | // R_ARM_MOVT_ABS: S + A |
| 2056 | static inline typename This::Status |
| 2057 | movt_abs(unsigned char *view, |
| 2058 | const Sized_relobj<32, big_endian>* object, |
| 2059 | const Symbol_value<32>* psymval) |
| 2060 | { |
| 2061 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2062 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2063 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2064 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2065 | Valtype x = psymval->value(object, addend) >> 16; |
| 2066 | val = This::insert_val_arm_movw_movt(val, x); |
| 2067 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2068 | return This::STATUS_OKAY; |
| 2069 | } |
| 2070 | |
| 2071 | // R_ARM_THM_MOVW_ABS_NC: S + A | T |
| 2072 | static inline typename This::Status |
| 2073 | thm_movw_abs_nc(unsigned char *view, |
| 2074 | const Sized_relobj<32, big_endian>* object, |
| 2075 | const Symbol_value<32>* psymval, |
| 2076 | Arm_address thumb_bit) |
| 2077 | { |
| 2078 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2079 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2080 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2081 | Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2082 | | elfcpp::Swap<16, big_endian>::readval(wv + 1)); |
| 2083 | Reltype addend = extract_thumb_movw_movt_addend(val); |
| 2084 | Reltype x = psymval->value(object, addend) | thumb_bit; |
| 2085 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2086 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2087 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2088 | return This::STATUS_OKAY; |
| 2089 | } |
| 2090 | |
| 2091 | // R_ARM_THM_MOVT_ABS: S + A |
| 2092 | static inline typename This::Status |
| 2093 | thm_movt_abs(unsigned char *view, |
| 2094 | const Sized_relobj<32, big_endian>* object, |
| 2095 | const Symbol_value<32>* psymval) |
| 2096 | { |
| 2097 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2098 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2099 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2100 | Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2101 | | elfcpp::Swap<16, big_endian>::readval(wv + 1)); |
| 2102 | Reltype addend = This::extract_thumb_movw_movt_addend(val); |
| 2103 | Reltype x = psymval->value(object, addend) >> 16; |
| 2104 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2105 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2106 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2107 | return This::STATUS_OKAY; |
| 2108 | } |
| 2109 | |
| 2110 | // R_ARM_MOVW_PREL_NC: (S + A) | T - P |
| 2111 | static inline typename This::Status |
| 2112 | movw_prel_nc(unsigned char *view, |
| 2113 | const Sized_relobj<32, big_endian>* object, |
| 2114 | const Symbol_value<32>* psymval, |
| 2115 | Arm_address address, |
| 2116 | Arm_address thumb_bit) |
| 2117 | { |
| 2118 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2119 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2120 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2121 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2122 | Valtype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 2123 | val = This::insert_val_arm_movw_movt(val, x); |
| 2124 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2125 | return This::STATUS_OKAY; |
| 2126 | } |
| 2127 | |
| 2128 | // R_ARM_MOVT_PREL: S + A - P |
| 2129 | static inline typename This::Status |
| 2130 | movt_prel(unsigned char *view, |
| 2131 | const Sized_relobj<32, big_endian>* object, |
| 2132 | const Symbol_value<32>* psymval, |
| 2133 | Arm_address address) |
| 2134 | { |
| 2135 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 2136 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2137 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 2138 | Valtype addend = This::extract_arm_movw_movt_addend(val); |
| 2139 | Valtype x = (psymval->value(object, addend) - address) >> 16; |
| 2140 | val = This::insert_val_arm_movw_movt(val, x); |
| 2141 | elfcpp::Swap<32, big_endian>::writeval(wv, val); |
| 2142 | return This::STATUS_OKAY; |
| 2143 | } |
| 2144 | |
| 2145 | // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P |
| 2146 | static inline typename This::Status |
| 2147 | thm_movw_prel_nc(unsigned char *view, |
| 2148 | const Sized_relobj<32, big_endian>* object, |
| 2149 | const Symbol_value<32>* psymval, |
| 2150 | Arm_address address, |
| 2151 | Arm_address thumb_bit) |
| 2152 | { |
| 2153 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2154 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2155 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2156 | Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2157 | | elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 2158 | Reltype addend = This::extract_thumb_movw_movt_addend(val); |
| 2159 | Reltype x = (psymval->value(object, addend) | thumb_bit) - address; |
| 2160 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2161 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2162 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2163 | return This::STATUS_OKAY; |
| 2164 | } |
| 2165 | |
| 2166 | // R_ARM_THM_MOVT_PREL: S + A - P |
| 2167 | static inline typename This::Status |
| 2168 | thm_movt_prel(unsigned char *view, |
| 2169 | const Sized_relobj<32, big_endian>* object, |
| 2170 | const Symbol_value<32>* psymval, |
| 2171 | Arm_address address) |
| 2172 | { |
| 2173 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 2174 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype; |
| 2175 | Valtype* wv = reinterpret_cast<Valtype*>(view); |
| 2176 | Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16) |
| 2177 | | elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 2178 | Reltype addend = This::extract_thumb_movw_movt_addend(val); |
| 2179 | Reltype x = (psymval->value(object, addend) - address) >> 16; |
| 2180 | val = This::insert_val_thumb_movw_movt(val, x); |
| 2181 | elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16); |
| 2182 | elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff); |
| 2183 | return This::STATUS_OKAY; |
| 2184 | } |
| 2185 | }; |
| 2186 | |
| 2187 | // Get the GOT section, creating it if necessary. |
| 2188 | |
| 2189 | template<bool big_endian> |
| 2190 | Output_data_got<32, big_endian>* |
| 2191 | Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout) |
| 2192 | { |
| 2193 | if (this->got_ == NULL) |
| 2194 | { |
| 2195 | gold_assert(symtab != NULL && layout != NULL); |
| 2196 | |
| 2197 | this->got_ = new Output_data_got<32, big_endian>(); |
| 2198 | |
| 2199 | Output_section* os; |
| 2200 | os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, |
| 2201 | (elfcpp::SHF_ALLOC |
| 2202 | | elfcpp::SHF_WRITE), |
| 2203 | this->got_, false); |
| 2204 | os->set_is_relro(); |
| 2205 | |
| 2206 | // The old GNU linker creates a .got.plt section. We just |
| 2207 | // create another set of data in the .got section. Note that we |
| 2208 | // always create a PLT if we create a GOT, although the PLT |
| 2209 | // might be empty. |
| 2210 | this->got_plt_ = new Output_data_space(4, "** GOT PLT"); |
| 2211 | os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, |
| 2212 | (elfcpp::SHF_ALLOC |
| 2213 | | elfcpp::SHF_WRITE), |
| 2214 | this->got_plt_, false); |
| 2215 | os->set_is_relro(); |
| 2216 | |
| 2217 | // The first three entries are reserved. |
| 2218 | this->got_plt_->set_current_data_size(3 * 4); |
| 2219 | |
| 2220 | // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. |
| 2221 | symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL, |
| 2222 | this->got_plt_, |
| 2223 | 0, 0, elfcpp::STT_OBJECT, |
| 2224 | elfcpp::STB_LOCAL, |
| 2225 | elfcpp::STV_HIDDEN, 0, |
| 2226 | false, false); |
| 2227 | } |
| 2228 | return this->got_; |
| 2229 | } |
| 2230 | |
| 2231 | // Get the dynamic reloc section, creating it if necessary. |
| 2232 | |
| 2233 | template<bool big_endian> |
| 2234 | typename Target_arm<big_endian>::Reloc_section* |
| 2235 | Target_arm<big_endian>::rel_dyn_section(Layout* layout) |
| 2236 | { |
| 2237 | if (this->rel_dyn_ == NULL) |
| 2238 | { |
| 2239 | gold_assert(layout != NULL); |
| 2240 | this->rel_dyn_ = new Reloc_section(parameters->options().combreloc()); |
| 2241 | layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL, |
| 2242 | elfcpp::SHF_ALLOC, this->rel_dyn_, true); |
| 2243 | } |
| 2244 | return this->rel_dyn_; |
| 2245 | } |
| 2246 | |
| 2247 | // Insn_template methods. |
| 2248 | |
| 2249 | // Return byte size of an instruction template. |
| 2250 | |
| 2251 | size_t |
| 2252 | Insn_template::size() const |
| 2253 | { |
| 2254 | switch (this->type()) |
| 2255 | { |
| 2256 | case THUMB16_TYPE: |
| 2257 | return 2; |
| 2258 | case ARM_TYPE: |
| 2259 | case THUMB32_TYPE: |
| 2260 | case DATA_TYPE: |
| 2261 | return 4; |
| 2262 | default: |
| 2263 | gold_unreachable(); |
| 2264 | } |
| 2265 | } |
| 2266 | |
| 2267 | // Return alignment of an instruction template. |
| 2268 | |
| 2269 | unsigned |
| 2270 | Insn_template::alignment() const |
| 2271 | { |
| 2272 | switch (this->type()) |
| 2273 | { |
| 2274 | case THUMB16_TYPE: |
| 2275 | case THUMB32_TYPE: |
| 2276 | return 2; |
| 2277 | case ARM_TYPE: |
| 2278 | case DATA_TYPE: |
| 2279 | return 4; |
| 2280 | default: |
| 2281 | gold_unreachable(); |
| 2282 | } |
| 2283 | } |
| 2284 | |
| 2285 | // Stub_template methods. |
| 2286 | |
| 2287 | Stub_template::Stub_template( |
| 2288 | Stub_type type, const Insn_template* insns, |
| 2289 | size_t insn_count) |
| 2290 | : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1), |
| 2291 | entry_in_thumb_mode_(false), relocs_() |
| 2292 | { |
| 2293 | off_t offset = 0; |
| 2294 | |
| 2295 | // Compute byte size and alignment of stub template. |
| 2296 | for (size_t i = 0; i < insn_count; i++) |
| 2297 | { |
| 2298 | unsigned insn_alignment = insns[i].alignment(); |
| 2299 | size_t insn_size = insns[i].size(); |
| 2300 | gold_assert((offset & (insn_alignment - 1)) == 0); |
| 2301 | this->alignment_ = std::max(this->alignment_, insn_alignment); |
| 2302 | switch (insns[i].type()) |
| 2303 | { |
| 2304 | case Insn_template::THUMB16_TYPE: |
| 2305 | if (i == 0) |
| 2306 | this->entry_in_thumb_mode_ = true; |
| 2307 | break; |
| 2308 | |
| 2309 | case Insn_template::THUMB32_TYPE: |
| 2310 | if (insns[i].r_type() != elfcpp::R_ARM_NONE) |
| 2311 | this->relocs_.push_back(Reloc(i, offset)); |
| 2312 | if (i == 0) |
| 2313 | this->entry_in_thumb_mode_ = true; |
| 2314 | break; |
| 2315 | |
| 2316 | case Insn_template::ARM_TYPE: |
| 2317 | // Handle cases where the target is encoded within the |
| 2318 | // instruction. |
| 2319 | if (insns[i].r_type() == elfcpp::R_ARM_JUMP24) |
| 2320 | this->relocs_.push_back(Reloc(i, offset)); |
| 2321 | break; |
| 2322 | |
| 2323 | case Insn_template::DATA_TYPE: |
| 2324 | // Entry point cannot be data. |
| 2325 | gold_assert(i != 0); |
| 2326 | this->relocs_.push_back(Reloc(i, offset)); |
| 2327 | break; |
| 2328 | |
| 2329 | default: |
| 2330 | gold_unreachable(); |
| 2331 | } |
| 2332 | offset += insn_size; |
| 2333 | } |
| 2334 | this->size_ = offset; |
| 2335 | } |
| 2336 | |
| 2337 | // Reloc_stub::Key methods. |
| 2338 | |
| 2339 | // Dump a Key as a string for debugging. |
| 2340 | |
| 2341 | std::string |
| 2342 | Reloc_stub::Key::name() const |
| 2343 | { |
| 2344 | if (this->r_sym_ == invalid_index) |
| 2345 | { |
| 2346 | // Global symbol key name |
| 2347 | // <stub-type>:<symbol name>:<addend>. |
| 2348 | const std::string sym_name = this->u_.symbol->name(); |
| 2349 | // We need to print two hex number and two colons. So just add 100 bytes |
| 2350 | // to the symbol name size. |
| 2351 | size_t len = sym_name.size() + 100; |
| 2352 | char* buffer = new char[len]; |
| 2353 | int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_, |
| 2354 | sym_name.c_str(), this->addend_); |
| 2355 | gold_assert(c > 0 && c < static_cast<int>(len)); |
| 2356 | delete[] buffer; |
| 2357 | return std::string(buffer); |
| 2358 | } |
| 2359 | else |
| 2360 | { |
| 2361 | // local symbol key name |
| 2362 | // <stub-type>:<object>:<r_sym>:<addend>. |
| 2363 | const size_t len = 200; |
| 2364 | char buffer[len]; |
| 2365 | int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_, |
| 2366 | this->u_.relobj, this->r_sym_, this->addend_); |
| 2367 | gold_assert(c > 0 && c < static_cast<int>(len)); |
| 2368 | return std::string(buffer); |
| 2369 | } |
| 2370 | } |
| 2371 | |
| 2372 | // Reloc_stub methods. |
| 2373 | |
| 2374 | // Determine the type of stub needed, if any, for a relocation of R_TYPE at |
| 2375 | // LOCATION to DESTINATION. |
| 2376 | // This code is based on the arm_type_of_stub function in |
| 2377 | // bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub |
| 2378 | // class simple. |
| 2379 | |
| 2380 | Stub_type |
| 2381 | Reloc_stub::stub_type_for_reloc( |
| 2382 | unsigned int r_type, |
| 2383 | Arm_address location, |
| 2384 | Arm_address destination, |
| 2385 | bool target_is_thumb) |
| 2386 | { |
| 2387 | Stub_type stub_type = arm_stub_none; |
| 2388 | |
| 2389 | // This is a bit ugly but we want to avoid using a templated class for |
| 2390 | // big and little endianities. |
| 2391 | bool may_use_blx; |
| 2392 | bool should_force_pic_veneer; |
| 2393 | bool thumb2; |
| 2394 | bool thumb_only; |
| 2395 | if (parameters->target().is_big_endian()) |
| 2396 | { |
| 2397 | const Target_arm<true>* big_endian_target = |
| 2398 | Target_arm<true>::default_target(); |
| 2399 | may_use_blx = big_endian_target->may_use_blx(); |
| 2400 | should_force_pic_veneer = big_endian_target->should_force_pic_veneer(); |
| 2401 | thumb2 = big_endian_target->using_thumb2(); |
| 2402 | thumb_only = big_endian_target->using_thumb_only(); |
| 2403 | } |
| 2404 | else |
| 2405 | { |
| 2406 | const Target_arm<false>* little_endian_target = |
| 2407 | Target_arm<false>::default_target(); |
| 2408 | may_use_blx = little_endian_target->may_use_blx(); |
| 2409 | should_force_pic_veneer = little_endian_target->should_force_pic_veneer(); |
| 2410 | thumb2 = little_endian_target->using_thumb2(); |
| 2411 | thumb_only = little_endian_target->using_thumb_only(); |
| 2412 | } |
| 2413 | |
| 2414 | int64_t branch_offset = (int64_t)destination - location; |
| 2415 | |
| 2416 | if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24) |
| 2417 | { |
| 2418 | // Handle cases where: |
| 2419 | // - this call goes too far (different Thumb/Thumb2 max |
| 2420 | // distance) |
| 2421 | // - it's a Thumb->Arm call and blx is not available, or it's a |
| 2422 | // Thumb->Arm branch (not bl). A stub is needed in this case. |
| 2423 | if ((!thumb2 |
| 2424 | && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET |
| 2425 | || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET))) |
| 2426 | || (thumb2 |
| 2427 | && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET |
| 2428 | || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET))) |
| 2429 | || ((!target_is_thumb) |
| 2430 | && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx) |
| 2431 | || (r_type == elfcpp::R_ARM_THM_JUMP24)))) |
| 2432 | { |
| 2433 | if (target_is_thumb) |
| 2434 | { |
| 2435 | // Thumb to thumb. |
| 2436 | if (!thumb_only) |
| 2437 | { |
| 2438 | stub_type = (parameters->options().shared() | should_force_pic_veneer) |
| 2439 | // PIC stubs. |
| 2440 | ? ((may_use_blx |
| 2441 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 2442 | // V5T and above. Stub starts with ARM code, so |
| 2443 | // we must be able to switch mode before |
| 2444 | // reaching it, which is only possible for 'bl' |
| 2445 | // (ie R_ARM_THM_CALL relocation). |
| 2446 | ? arm_stub_long_branch_any_thumb_pic |
| 2447 | // On V4T, use Thumb code only. |
| 2448 | : arm_stub_long_branch_v4t_thumb_thumb_pic) |
| 2449 | |
| 2450 | // non-PIC stubs. |
| 2451 | : ((may_use_blx |
| 2452 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 2453 | ? arm_stub_long_branch_any_any // V5T and above. |
| 2454 | : arm_stub_long_branch_v4t_thumb_thumb); // V4T. |
| 2455 | } |
| 2456 | else |
| 2457 | { |
| 2458 | stub_type = (parameters->options().shared() | should_force_pic_veneer) |
| 2459 | ? arm_stub_long_branch_thumb_only_pic // PIC stub. |
| 2460 | : arm_stub_long_branch_thumb_only; // non-PIC stub. |
| 2461 | } |
| 2462 | } |
| 2463 | else |
| 2464 | { |
| 2465 | // Thumb to arm. |
| 2466 | |
| 2467 | // FIXME: We should check that the input section is from an |
| 2468 | // object that has interwork enabled. |
| 2469 | |
| 2470 | stub_type = (parameters->options().shared() |
| 2471 | || should_force_pic_veneer) |
| 2472 | // PIC stubs. |
| 2473 | ? ((may_use_blx |
| 2474 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 2475 | ? arm_stub_long_branch_any_arm_pic // V5T and above. |
| 2476 | : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T. |
| 2477 | |
| 2478 | // non-PIC stubs. |
| 2479 | : ((may_use_blx |
| 2480 | && (r_type == elfcpp::R_ARM_THM_CALL)) |
| 2481 | ? arm_stub_long_branch_any_any // V5T and above. |
| 2482 | : arm_stub_long_branch_v4t_thumb_arm); // V4T. |
| 2483 | |
| 2484 | // Handle v4t short branches. |
| 2485 | if ((stub_type == arm_stub_long_branch_v4t_thumb_arm) |
| 2486 | && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET) |
| 2487 | && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET)) |
| 2488 | stub_type = arm_stub_short_branch_v4t_thumb_arm; |
| 2489 | } |
| 2490 | } |
| 2491 | } |
| 2492 | else if (r_type == elfcpp::R_ARM_CALL |
| 2493 | || r_type == elfcpp::R_ARM_JUMP24 |
| 2494 | || r_type == elfcpp::R_ARM_PLT32) |
| 2495 | { |
| 2496 | if (target_is_thumb) |
| 2497 | { |
| 2498 | // Arm to thumb. |
| 2499 | |
| 2500 | // FIXME: We should check that the input section is from an |
| 2501 | // object that has interwork enabled. |
| 2502 | |
| 2503 | // We have an extra 2-bytes reach because of |
| 2504 | // the mode change (bit 24 (H) of BLX encoding). |
| 2505 | if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2) |
| 2506 | || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET) |
| 2507 | || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx) |
| 2508 | || (r_type == elfcpp::R_ARM_JUMP24) |
| 2509 | || (r_type == elfcpp::R_ARM_PLT32)) |
| 2510 | { |
| 2511 | stub_type = (parameters->options().shared() |
| 2512 | || should_force_pic_veneer) |
| 2513 | // PIC stubs. |
| 2514 | ? (may_use_blx |
| 2515 | ? arm_stub_long_branch_any_thumb_pic// V5T and above. |
| 2516 | : arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub. |
| 2517 | |
| 2518 | // non-PIC stubs. |
| 2519 | : (may_use_blx |
| 2520 | ? arm_stub_long_branch_any_any // V5T and above. |
| 2521 | : arm_stub_long_branch_v4t_arm_thumb); // V4T. |
| 2522 | } |
| 2523 | } |
| 2524 | else |
| 2525 | { |
| 2526 | // Arm to arm. |
| 2527 | if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET |
| 2528 | || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)) |
| 2529 | { |
| 2530 | stub_type = (parameters->options().shared() |
| 2531 | || should_force_pic_veneer) |
| 2532 | ? arm_stub_long_branch_any_arm_pic // PIC stubs. |
| 2533 | : arm_stub_long_branch_any_any; /// non-PIC. |
| 2534 | } |
| 2535 | } |
| 2536 | } |
| 2537 | |
| 2538 | return stub_type; |
| 2539 | } |
| 2540 | |
| 2541 | // Template to implement do_write for a specific target endianity. |
| 2542 | |
| 2543 | template<bool big_endian> |
| 2544 | void inline |
| 2545 | Reloc_stub::do_fixed_endian_write(unsigned char* view, |
| 2546 | section_size_type view_size) |
| 2547 | { |
| 2548 | const Stub_template* stub_template = this->stub_template(); |
| 2549 | const Insn_template* insns = stub_template->insns(); |
| 2550 | |
| 2551 | // FIXME: We do not handle BE8 encoding yet. |
| 2552 | unsigned char* pov = view; |
| 2553 | for (size_t i = 0; i < stub_template->insn_count(); i++) |
| 2554 | { |
| 2555 | switch (insns[i].type()) |
| 2556 | { |
| 2557 | case Insn_template::THUMB16_TYPE: |
| 2558 | // Non-zero reloc addends are only used in Cortex-A8 stubs. |
| 2559 | gold_assert(insns[i].reloc_addend() == 0); |
| 2560 | elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff); |
| 2561 | break; |
| 2562 | case Insn_template::THUMB32_TYPE: |
| 2563 | { |
| 2564 | uint32_t hi = (insns[i].data() >> 16) & 0xffff; |
| 2565 | uint32_t lo = insns[i].data() & 0xffff; |
| 2566 | elfcpp::Swap<16, big_endian>::writeval(pov, hi); |
| 2567 | elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo); |
| 2568 | } |
| 2569 | break; |
| 2570 | case Insn_template::ARM_TYPE: |
| 2571 | case Insn_template::DATA_TYPE: |
| 2572 | elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data()); |
| 2573 | break; |
| 2574 | default: |
| 2575 | gold_unreachable(); |
| 2576 | } |
| 2577 | pov += insns[i].size(); |
| 2578 | } |
| 2579 | gold_assert(static_cast<section_size_type>(pov - view) == view_size); |
| 2580 | } |
| 2581 | |
| 2582 | // Write a reloc stub to VIEW with endianity specified by BIG_ENDIAN. |
| 2583 | |
| 2584 | void |
| 2585 | Reloc_stub::do_write(unsigned char* view, section_size_type view_size, |
| 2586 | bool big_endian) |
| 2587 | { |
| 2588 | if (big_endian) |
| 2589 | this->do_fixed_endian_write<true>(view, view_size); |
| 2590 | else |
| 2591 | this->do_fixed_endian_write<false>(view, view_size); |
| 2592 | } |
| 2593 | |
| 2594 | // Stub_factory methods. |
| 2595 | |
| 2596 | Stub_factory::Stub_factory() |
| 2597 | { |
| 2598 | // The instruction template sequences are declared as static |
| 2599 | // objects and initialized first time the constructor runs. |
| 2600 | |
| 2601 | // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx |
| 2602 | // to reach the stub if necessary. |
| 2603 | static const Insn_template elf32_arm_stub_long_branch_any_any[] = |
| 2604 | { |
| 2605 | Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4] |
| 2606 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 2607 | // dcd R_ARM_ABS32(X) |
| 2608 | }; |
| 2609 | |
| 2610 | // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not |
| 2611 | // available. |
| 2612 | static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] = |
| 2613 | { |
| 2614 | Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0] |
| 2615 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 2616 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 2617 | // dcd R_ARM_ABS32(X) |
| 2618 | }; |
| 2619 | |
| 2620 | // Thumb -> Thumb long branch stub. Used on M-profile architectures. |
| 2621 | static const Insn_template elf32_arm_stub_long_branch_thumb_only[] = |
| 2622 | { |
| 2623 | Insn_template::thumb16_insn(0xb401), // push {r0} |
| 2624 | Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8] |
| 2625 | Insn_template::thumb16_insn(0x4684), // mov ip, r0 |
| 2626 | Insn_template::thumb16_insn(0xbc01), // pop {r0} |
| 2627 | Insn_template::thumb16_insn(0x4760), // bx ip |
| 2628 | Insn_template::thumb16_insn(0xbf00), // nop |
| 2629 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 2630 | // dcd R_ARM_ABS32(X) |
| 2631 | }; |
| 2632 | |
| 2633 | // V4T Thumb -> Thumb long branch stub. Using the stack is not |
| 2634 | // allowed. |
| 2635 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] = |
| 2636 | { |
| 2637 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 2638 | Insn_template::thumb16_insn(0x46c0), // nop |
| 2639 | Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0] |
| 2640 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 2641 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 2642 | // dcd R_ARM_ABS32(X) |
| 2643 | }; |
| 2644 | |
| 2645 | // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not |
| 2646 | // available. |
| 2647 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] = |
| 2648 | { |
| 2649 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 2650 | Insn_template::thumb16_insn(0x46c0), // nop |
| 2651 | Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4] |
| 2652 | Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0), |
| 2653 | // dcd R_ARM_ABS32(X) |
| 2654 | }; |
| 2655 | |
| 2656 | // V4T Thumb -> ARM short branch stub. Shorter variant of the above |
| 2657 | // one, when the destination is close enough. |
| 2658 | static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] = |
| 2659 | { |
| 2660 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 2661 | Insn_template::thumb16_insn(0x46c0), // nop |
| 2662 | Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8) |
| 2663 | }; |
| 2664 | |
| 2665 | // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use |
| 2666 | // blx to reach the stub if necessary. |
| 2667 | static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] = |
| 2668 | { |
| 2669 | Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc] |
| 2670 | Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip |
| 2671 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4), |
| 2672 | // dcd R_ARM_REL32(X-4) |
| 2673 | }; |
| 2674 | |
| 2675 | // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use |
| 2676 | // blx to reach the stub if necessary. We can not add into pc; |
| 2677 | // it is not guaranteed to mode switch (different in ARMv6 and |
| 2678 | // ARMv7). |
| 2679 | static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] = |
| 2680 | { |
| 2681 | Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4] |
| 2682 | Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip |
| 2683 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 2684 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0), |
| 2685 | // dcd R_ARM_REL32(X) |
| 2686 | }; |
| 2687 | |
| 2688 | // V4T ARM -> ARM long branch stub, PIC. |
| 2689 | static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] = |
| 2690 | { |
| 2691 | Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4] |
| 2692 | Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip |
| 2693 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 2694 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0), |
| 2695 | // dcd R_ARM_REL32(X) |
| 2696 | }; |
| 2697 | |
| 2698 | // V4T Thumb -> ARM long branch stub, PIC. |
| 2699 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] = |
| 2700 | { |
| 2701 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 2702 | Insn_template::thumb16_insn(0x46c0), // nop |
| 2703 | Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0] |
| 2704 | Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc |
| 2705 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4), |
| 2706 | // dcd R_ARM_REL32(X) |
| 2707 | }; |
| 2708 | |
| 2709 | // Thumb -> Thumb long branch stub, PIC. Used on M-profile |
| 2710 | // architectures. |
| 2711 | static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] = |
| 2712 | { |
| 2713 | Insn_template::thumb16_insn(0xb401), // push {r0} |
| 2714 | Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8] |
| 2715 | Insn_template::thumb16_insn(0x46fc), // mov ip, pc |
| 2716 | Insn_template::thumb16_insn(0x4484), // add ip, r0 |
| 2717 | Insn_template::thumb16_insn(0xbc01), // pop {r0} |
| 2718 | Insn_template::thumb16_insn(0x4760), // bx ip |
| 2719 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4), |
| 2720 | // dcd R_ARM_REL32(X) |
| 2721 | }; |
| 2722 | |
| 2723 | // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not |
| 2724 | // allowed. |
| 2725 | static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] = |
| 2726 | { |
| 2727 | Insn_template::thumb16_insn(0x4778), // bx pc |
| 2728 | Insn_template::thumb16_insn(0x46c0), // nop |
| 2729 | Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4] |
| 2730 | Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip |
| 2731 | Insn_template::arm_insn(0xe12fff1c), // bx ip |
| 2732 | Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0), |
| 2733 | // dcd R_ARM_REL32(X) |
| 2734 | }; |
| 2735 | |
| 2736 | // Cortex-A8 erratum-workaround stubs. |
| 2737 | |
| 2738 | // Stub used for conditional branches (which may be beyond +/-1MB away, |
| 2739 | // so we can't use a conditional branch to reach this stub). |
| 2740 | |
| 2741 | // original code: |
| 2742 | // |
| 2743 | // b<cond> X |
| 2744 | // after: |
| 2745 | // |
| 2746 | static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] = |
| 2747 | { |
| 2748 | Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true |
| 2749 | Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after |
| 2750 | Insn_template::thumb32_b_insn(0xf000b800, -4) // true: |
| 2751 | // b.w X |
| 2752 | }; |
| 2753 | |
| 2754 | // Stub used for b.w and bl.w instructions. |
| 2755 | |
| 2756 | static const Insn_template elf32_arm_stub_a8_veneer_b[] = |
| 2757 | { |
| 2758 | Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest |
| 2759 | }; |
| 2760 | |
| 2761 | static const Insn_template elf32_arm_stub_a8_veneer_bl[] = |
| 2762 | { |
| 2763 | Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest |
| 2764 | }; |
| 2765 | |
| 2766 | // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w |
| 2767 | // instruction (which switches to ARM mode) to point to this stub. Jump to |
| 2768 | // the real destination using an ARM-mode branch. |
| 2769 | const Insn_template elf32_arm_stub_a8_veneer_blx[] = |
| 2770 | { |
| 2771 | Insn_template::arm_rel_insn(0xea000000, -8) // b dest |
| 2772 | }; |
| 2773 | |
| 2774 | // Fill in the stub template look-up table. Stub templates are constructed |
| 2775 | // per instance of Stub_factory for fast look-up without locking |
| 2776 | // in a thread-enabled environment. |
| 2777 | |
| 2778 | this->stub_templates_[arm_stub_none] = |
| 2779 | new Stub_template(arm_stub_none, NULL, 0); |
| 2780 | |
| 2781 | #define DEF_STUB(x) \ |
| 2782 | do \ |
| 2783 | { \ |
| 2784 | size_t array_size \ |
| 2785 | = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \ |
| 2786 | Stub_type type = arm_stub_##x; \ |
| 2787 | this->stub_templates_[type] = \ |
| 2788 | new Stub_template(type, elf32_arm_stub_##x, array_size); \ |
| 2789 | } \ |
| 2790 | while (0); |
| 2791 | |
| 2792 | DEF_STUBS |
| 2793 | #undef DEF_STUB |
| 2794 | } |
| 2795 | |
| 2796 | // Stub_table methods. |
| 2797 | |
| 2798 | // Add a STUB with using KEY. Caller is reponsible for avoid adding |
| 2799 | // if already a STUB with the same key has been added. |
| 2800 | |
| 2801 | template<bool big_endian> |
| 2802 | void |
| 2803 | Stub_table<big_endian>::add_reloc_stub( |
| 2804 | Reloc_stub* stub, |
| 2805 | const Reloc_stub::Key& key) |
| 2806 | { |
| 2807 | const Stub_template* stub_template = stub->stub_template(); |
| 2808 | gold_assert(stub_template->type() == key.stub_type()); |
| 2809 | this->reloc_stubs_[key] = stub; |
| 2810 | if (this->addralign_ < stub_template->alignment()) |
| 2811 | this->addralign_ = stub_template->alignment(); |
| 2812 | this->has_been_changed_ = true; |
| 2813 | } |
| 2814 | |
| 2815 | template<bool big_endian> |
| 2816 | void |
| 2817 | Stub_table<big_endian>::relocate_stubs( |
| 2818 | const Relocate_info<32, big_endian>* relinfo, |
| 2819 | Target_arm<big_endian>* arm_target, |
| 2820 | Output_section* output_section, |
| 2821 | unsigned char* view, |
| 2822 | Arm_address address, |
| 2823 | section_size_type view_size) |
| 2824 | { |
| 2825 | // If we are passed a view bigger than the stub table's. we need to |
| 2826 | // adjust the view. |
| 2827 | gold_assert(address == this->address() |
| 2828 | && (view_size |
| 2829 | == static_cast<section_size_type>(this->data_size()))); |
| 2830 | |
| 2831 | for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin(); |
| 2832 | p != this->reloc_stubs_.end(); |
| 2833 | ++p) |
| 2834 | { |
| 2835 | Reloc_stub* stub = p->second; |
| 2836 | const Stub_template* stub_template = stub->stub_template(); |
| 2837 | if (stub_template->reloc_count() != 0) |
| 2838 | { |
| 2839 | // Adjust view to cover the stub only. |
| 2840 | section_size_type offset = stub->offset(); |
| 2841 | section_size_type stub_size = stub_template->size(); |
| 2842 | gold_assert(offset + stub_size <= view_size); |
| 2843 | |
| 2844 | arm_target->relocate_stub(stub, relinfo, output_section, |
| 2845 | view + offset, address + offset, |
| 2846 | stub_size); |
| 2847 | } |
| 2848 | } |
| 2849 | } |
| 2850 | |
| 2851 | // Reset address and file offset. |
| 2852 | |
| 2853 | template<bool big_endian> |
| 2854 | void |
| 2855 | Stub_table<big_endian>::do_reset_address_and_file_offset() |
| 2856 | { |
| 2857 | off_t off = 0; |
| 2858 | uint64_t max_addralign = 1; |
| 2859 | for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin(); |
| 2860 | p != this->reloc_stubs_.end(); |
| 2861 | ++p) |
| 2862 | { |
| 2863 | Reloc_stub* stub = p->second; |
| 2864 | const Stub_template* stub_template = stub->stub_template(); |
| 2865 | uint64_t stub_addralign = stub_template->alignment(); |
| 2866 | max_addralign = std::max(max_addralign, stub_addralign); |
| 2867 | off = align_address(off, stub_addralign); |
| 2868 | stub->set_offset(off); |
| 2869 | stub->reset_destination_address(); |
| 2870 | off += stub_template->size(); |
| 2871 | } |
| 2872 | |
| 2873 | this->addralign_ = max_addralign; |
| 2874 | this->set_current_data_size_for_child(off); |
| 2875 | } |
| 2876 | |
| 2877 | // Write out the stubs to file. |
| 2878 | |
| 2879 | template<bool big_endian> |
| 2880 | void |
| 2881 | Stub_table<big_endian>::do_write(Output_file* of) |
| 2882 | { |
| 2883 | off_t offset = this->offset(); |
| 2884 | const section_size_type oview_size = |
| 2885 | convert_to_section_size_type(this->data_size()); |
| 2886 | unsigned char* const oview = of->get_output_view(offset, oview_size); |
| 2887 | |
| 2888 | for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin(); |
| 2889 | p != this->reloc_stubs_.end(); |
| 2890 | ++p) |
| 2891 | { |
| 2892 | Reloc_stub* stub = p->second; |
| 2893 | Arm_address address = this->address() + stub->offset(); |
| 2894 | gold_assert(address |
| 2895 | == align_address(address, |
| 2896 | stub->stub_template()->alignment())); |
| 2897 | stub->write(oview + stub->offset(), stub->stub_template()->size(), |
| 2898 | big_endian); |
| 2899 | } |
| 2900 | of->write_output_view(this->offset(), oview_size, oview); |
| 2901 | } |
| 2902 | |
| 2903 | // Arm_input_section methods. |
| 2904 | |
| 2905 | // Initialize an Arm_input_section. |
| 2906 | |
| 2907 | template<bool big_endian> |
| 2908 | void |
| 2909 | Arm_input_section<big_endian>::init() |
| 2910 | { |
| 2911 | Relobj* relobj = this->relobj(); |
| 2912 | unsigned int shndx = this->shndx(); |
| 2913 | |
| 2914 | // Cache these to speed up size and alignment queries. It is too slow |
| 2915 | // to call section_addraglin and section_size every time. |
| 2916 | this->original_addralign_ = relobj->section_addralign(shndx); |
| 2917 | this->original_size_ = relobj->section_size(shndx); |
| 2918 | |
| 2919 | // We want to make this look like the original input section after |
| 2920 | // output sections are finalized. |
| 2921 | Output_section* os = relobj->output_section(shndx); |
| 2922 | off_t offset = relobj->output_section_offset(shndx); |
| 2923 | gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx)); |
| 2924 | this->set_address(os->address() + offset); |
| 2925 | this->set_file_offset(os->offset() + offset); |
| 2926 | |
| 2927 | this->set_current_data_size(this->original_size_); |
| 2928 | this->finalize_data_size(); |
| 2929 | } |
| 2930 | |
| 2931 | template<bool big_endian> |
| 2932 | void |
| 2933 | Arm_input_section<big_endian>::do_write(Output_file* of) |
| 2934 | { |
| 2935 | // We have to write out the original section content. |
| 2936 | section_size_type section_size; |
| 2937 | const unsigned char* section_contents = |
| 2938 | this->relobj()->section_contents(this->shndx(), §ion_size, false); |
| 2939 | of->write(this->offset(), section_contents, section_size); |
| 2940 | |
| 2941 | // If this owns a stub table and it is not empty, write it. |
| 2942 | if (this->is_stub_table_owner() && !this->stub_table_->empty()) |
| 2943 | this->stub_table_->write(of); |
| 2944 | } |
| 2945 | |
| 2946 | // Finalize data size. |
| 2947 | |
| 2948 | template<bool big_endian> |
| 2949 | void |
| 2950 | Arm_input_section<big_endian>::set_final_data_size() |
| 2951 | { |
| 2952 | // If this owns a stub table, finalize its data size as well. |
| 2953 | if (this->is_stub_table_owner()) |
| 2954 | { |
| 2955 | uint64_t address = this->address(); |
| 2956 | |
| 2957 | // The stub table comes after the original section contents. |
| 2958 | address += this->original_size_; |
| 2959 | address = align_address(address, this->stub_table_->addralign()); |
| 2960 | off_t offset = this->offset() + (address - this->address()); |
| 2961 | this->stub_table_->set_address_and_file_offset(address, offset); |
| 2962 | address += this->stub_table_->data_size(); |
| 2963 | gold_assert(address == this->address() + this->current_data_size()); |
| 2964 | } |
| 2965 | |
| 2966 | this->set_data_size(this->current_data_size()); |
| 2967 | } |
| 2968 | |
| 2969 | // Reset address and file offset. |
| 2970 | |
| 2971 | template<bool big_endian> |
| 2972 | void |
| 2973 | Arm_input_section<big_endian>::do_reset_address_and_file_offset() |
| 2974 | { |
| 2975 | // Size of the original input section contents. |
| 2976 | off_t off = convert_types<off_t, uint64_t>(this->original_size_); |
| 2977 | |
| 2978 | // If this is a stub table owner, account for the stub table size. |
| 2979 | if (this->is_stub_table_owner()) |
| 2980 | { |
| 2981 | Stub_table<big_endian>* stub_table = this->stub_table_; |
| 2982 | |
| 2983 | // Reset the stub table's address and file offset. The |
| 2984 | // current data size for child will be updated after that. |
| 2985 | stub_table_->reset_address_and_file_offset(); |
| 2986 | off = align_address(off, stub_table_->addralign()); |
| 2987 | off += stub_table->current_data_size(); |
| 2988 | } |
| 2989 | |
| 2990 | this->set_current_data_size(off); |
| 2991 | } |
| 2992 | |
| 2993 | // Arm_output_section methods. |
| 2994 | |
| 2995 | // Create a stub group for input sections from BEGIN to END. OWNER |
| 2996 | // points to the input section to be the owner a new stub table. |
| 2997 | |
| 2998 | template<bool big_endian> |
| 2999 | void |
| 3000 | Arm_output_section<big_endian>::create_stub_group( |
| 3001 | Input_section_list::const_iterator begin, |
| 3002 | Input_section_list::const_iterator end, |
| 3003 | Input_section_list::const_iterator owner, |
| 3004 | Target_arm<big_endian>* target, |
| 3005 | std::vector<Output_relaxed_input_section*>* new_relaxed_sections) |
| 3006 | { |
| 3007 | // Currently we convert ordinary input sections into relaxed sections only |
| 3008 | // at this point but we may want to support creating relaxed input section |
| 3009 | // very early. So we check here to see if owner is already a relaxed |
| 3010 | // section. |
| 3011 | |
| 3012 | Arm_input_section<big_endian>* arm_input_section; |
| 3013 | if (owner->is_relaxed_input_section()) |
| 3014 | { |
| 3015 | arm_input_section = |
| 3016 | Arm_input_section<big_endian>::as_arm_input_section( |
| 3017 | owner->relaxed_input_section()); |
| 3018 | } |
| 3019 | else |
| 3020 | { |
| 3021 | gold_assert(owner->is_input_section()); |
| 3022 | // Create a new relaxed input section. |
| 3023 | arm_input_section = |
| 3024 | target->new_arm_input_section(owner->relobj(), owner->shndx()); |
| 3025 | new_relaxed_sections->push_back(arm_input_section); |
| 3026 | } |
| 3027 | |
| 3028 | // Create a stub table. |
| 3029 | Stub_table<big_endian>* stub_table = |
| 3030 | target->new_stub_table(arm_input_section); |
| 3031 | |
| 3032 | arm_input_section->set_stub_table(stub_table); |
| 3033 | |
| 3034 | Input_section_list::const_iterator p = begin; |
| 3035 | Input_section_list::const_iterator prev_p; |
| 3036 | |
| 3037 | // Look for input sections or relaxed input sections in [begin ... end]. |
| 3038 | do |
| 3039 | { |
| 3040 | if (p->is_input_section() || p->is_relaxed_input_section()) |
| 3041 | { |
| 3042 | // The stub table information for input sections live |
| 3043 | // in their objects. |
| 3044 | Arm_relobj<big_endian>* arm_relobj = |
| 3045 | Arm_relobj<big_endian>::as_arm_relobj(p->relobj()); |
| 3046 | arm_relobj->set_stub_table(p->shndx(), stub_table); |
| 3047 | } |
| 3048 | prev_p = p++; |
| 3049 | } |
| 3050 | while (prev_p != end); |
| 3051 | } |
| 3052 | |
| 3053 | // Group input sections for stub generation. GROUP_SIZE is roughly the limit |
| 3054 | // of stub groups. We grow a stub group by adding input section until the |
| 3055 | // size is just below GROUP_SIZE. The last input section will be converted |
| 3056 | // into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add |
| 3057 | // input section after the stub table, effectively double the group size. |
| 3058 | // |
| 3059 | // This is similar to the group_sections() function in elf32-arm.c but is |
| 3060 | // implemented differently. |
| 3061 | |
| 3062 | template<bool big_endian> |
| 3063 | void |
| 3064 | Arm_output_section<big_endian>::group_sections( |
| 3065 | section_size_type group_size, |
| 3066 | bool stubs_always_after_branch, |
| 3067 | Target_arm<big_endian>* target) |
| 3068 | { |
| 3069 | // We only care about sections containing code. |
| 3070 | if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0) |
| 3071 | return; |
| 3072 | |
| 3073 | // States for grouping. |
| 3074 | typedef enum |
| 3075 | { |
| 3076 | // No group is being built. |
| 3077 | NO_GROUP, |
| 3078 | // A group is being built but the stub table is not found yet. |
| 3079 | // We keep group a stub group until the size is just under GROUP_SIZE. |
| 3080 | // The last input section in the group will be used as the stub table. |
| 3081 | FINDING_STUB_SECTION, |
| 3082 | // A group is being built and we have already found a stub table. |
| 3083 | // We enter this state to grow a stub group by adding input section |
| 3084 | // after the stub table. This effectively doubles the group size. |
| 3085 | HAS_STUB_SECTION |
| 3086 | } State; |
| 3087 | |
| 3088 | // Any newly created relaxed sections are stored here. |
| 3089 | std::vector<Output_relaxed_input_section*> new_relaxed_sections; |
| 3090 | |
| 3091 | State state = NO_GROUP; |
| 3092 | section_size_type off = 0; |
| 3093 | section_size_type group_begin_offset = 0; |
| 3094 | section_size_type group_end_offset = 0; |
| 3095 | section_size_type stub_table_end_offset = 0; |
| 3096 | Input_section_list::const_iterator group_begin = |
| 3097 | this->input_sections().end(); |
| 3098 | Input_section_list::const_iterator stub_table = |
| 3099 | this->input_sections().end(); |
| 3100 | Input_section_list::const_iterator group_end = this->input_sections().end(); |
| 3101 | for (Input_section_list::const_iterator p = this->input_sections().begin(); |
| 3102 | p != this->input_sections().end(); |
| 3103 | ++p) |
| 3104 | { |
| 3105 | section_size_type section_begin_offset = |
| 3106 | align_address(off, p->addralign()); |
| 3107 | section_size_type section_end_offset = |
| 3108 | section_begin_offset + p->data_size(); |
| 3109 | |
| 3110 | // Check to see if we should group the previously seens sections. |
| 3111 | switch (state) |
| 3112 | { |
| 3113 | case NO_GROUP: |
| 3114 | break; |
| 3115 | |
| 3116 | case FINDING_STUB_SECTION: |
| 3117 | // Adding this section makes the group larger than GROUP_SIZE. |
| 3118 | if (section_end_offset - group_begin_offset >= group_size) |
| 3119 | { |
| 3120 | if (stubs_always_after_branch) |
| 3121 | { |
| 3122 | gold_assert(group_end != this->input_sections().end()); |
| 3123 | this->create_stub_group(group_begin, group_end, group_end, |
| 3124 | target, &new_relaxed_sections); |
| 3125 | state = NO_GROUP; |
| 3126 | } |
| 3127 | else |
| 3128 | { |
| 3129 | // But wait, there's more! Input sections up to |
| 3130 | // stub_group_size bytes after the stub table can be |
| 3131 | // handled by it too. |
| 3132 | state = HAS_STUB_SECTION; |
| 3133 | stub_table = group_end; |
| 3134 | stub_table_end_offset = group_end_offset; |
| 3135 | } |
| 3136 | } |
| 3137 | break; |
| 3138 | |
| 3139 | case HAS_STUB_SECTION: |
| 3140 | // Adding this section makes the post stub-section group larger |
| 3141 | // than GROUP_SIZE. |
| 3142 | if (section_end_offset - stub_table_end_offset >= group_size) |
| 3143 | { |
| 3144 | gold_assert(group_end != this->input_sections().end()); |
| 3145 | this->create_stub_group(group_begin, group_end, stub_table, |
| 3146 | target, &new_relaxed_sections); |
| 3147 | state = NO_GROUP; |
| 3148 | } |
| 3149 | break; |
| 3150 | |
| 3151 | default: |
| 3152 | gold_unreachable(); |
| 3153 | } |
| 3154 | |
| 3155 | // If we see an input section and currently there is no group, start |
| 3156 | // a new one. Skip any empty sections. |
| 3157 | if ((p->is_input_section() || p->is_relaxed_input_section()) |
| 3158 | && (p->relobj()->section_size(p->shndx()) != 0)) |
| 3159 | { |
| 3160 | if (state == NO_GROUP) |
| 3161 | { |
| 3162 | state = FINDING_STUB_SECTION; |
| 3163 | group_begin = p; |
| 3164 | group_begin_offset = section_begin_offset; |
| 3165 | } |
| 3166 | |
| 3167 | // Keep track of the last input section seen. |
| 3168 | group_end = p; |
| 3169 | group_end_offset = section_end_offset; |
| 3170 | } |
| 3171 | |
| 3172 | off = section_end_offset; |
| 3173 | } |
| 3174 | |
| 3175 | // Create a stub group for any ungrouped sections. |
| 3176 | if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION) |
| 3177 | { |
| 3178 | gold_assert(group_end != this->input_sections().end()); |
| 3179 | this->create_stub_group(group_begin, group_end, |
| 3180 | (state == FINDING_STUB_SECTION |
| 3181 | ? group_end |
| 3182 | : stub_table), |
| 3183 | target, &new_relaxed_sections); |
| 3184 | } |
| 3185 | |
| 3186 | // Convert input section into relaxed input section in a batch. |
| 3187 | if (!new_relaxed_sections.empty()) |
| 3188 | this->convert_input_sections_to_relaxed_sections(new_relaxed_sections); |
| 3189 | |
| 3190 | // Update the section offsets |
| 3191 | for (size_t i = 0; i < new_relaxed_sections.size(); ++i) |
| 3192 | { |
| 3193 | Arm_relobj<big_endian>* arm_relobj = |
| 3194 | Arm_relobj<big_endian>::as_arm_relobj( |
| 3195 | new_relaxed_sections[i]->relobj()); |
| 3196 | unsigned int shndx = new_relaxed_sections[i]->shndx(); |
| 3197 | // Tell Arm_relobj that this input section is converted. |
| 3198 | arm_relobj->convert_input_section_to_relaxed_section(shndx); |
| 3199 | } |
| 3200 | } |
| 3201 | |
| 3202 | // Arm_relobj methods. |
| 3203 | |
| 3204 | // Scan relocations for stub generation. |
| 3205 | |
| 3206 | template<bool big_endian> |
| 3207 | void |
| 3208 | Arm_relobj<big_endian>::scan_sections_for_stubs( |
| 3209 | Target_arm<big_endian>* arm_target, |
| 3210 | const Symbol_table* symtab, |
| 3211 | const Layout* layout) |
| 3212 | { |
| 3213 | unsigned int shnum = this->shnum(); |
| 3214 | const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size; |
| 3215 | |
| 3216 | // Read the section headers. |
| 3217 | const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(), |
| 3218 | shnum * shdr_size, |
| 3219 | true, true); |
| 3220 | |
| 3221 | // To speed up processing, we set up hash tables for fast lookup of |
| 3222 | // input offsets to output addresses. |
| 3223 | this->initialize_input_to_output_maps(); |
| 3224 | |
| 3225 | const Relobj::Output_sections& out_sections(this->output_sections()); |
| 3226 | |
| 3227 | Relocate_info<32, big_endian> relinfo; |
| 3228 | relinfo.symtab = symtab; |
| 3229 | relinfo.layout = layout; |
| 3230 | relinfo.object = this; |
| 3231 | |
| 3232 | const unsigned char* p = pshdrs + shdr_size; |
| 3233 | for (unsigned int i = 1; i < shnum; ++i, p += shdr_size) |
| 3234 | { |
| 3235 | typename elfcpp::Shdr<32, big_endian> shdr(p); |
| 3236 | |
| 3237 | unsigned int sh_type = shdr.get_sh_type(); |
| 3238 | if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA) |
| 3239 | continue; |
| 3240 | |
| 3241 | off_t sh_size = shdr.get_sh_size(); |
| 3242 | if (sh_size == 0) |
| 3243 | continue; |
| 3244 | |
| 3245 | unsigned int index = this->adjust_shndx(shdr.get_sh_info()); |
| 3246 | if (index >= this->shnum()) |
| 3247 | { |
| 3248 | // Ignore reloc section with bad info. This error will be |
| 3249 | // reported in the final link. |
| 3250 | continue; |
| 3251 | } |
| 3252 | |
| 3253 | Output_section* os = out_sections[index]; |
| 3254 | if (os == NULL) |
| 3255 | { |
| 3256 | // This relocation section is against a section which we |
| 3257 | // discarded. |
| 3258 | continue; |
| 3259 | } |
| 3260 | Arm_address output_offset = this->get_output_section_offset(index); |
| 3261 | |
| 3262 | if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx()) |
| 3263 | { |
| 3264 | // Ignore reloc section with unexpected symbol table. The |
| 3265 | // error will be reported in the final link. |
| 3266 | continue; |
| 3267 | } |
| 3268 | |
| 3269 | const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(), |
| 3270 | sh_size, true, false); |
| 3271 | |
| 3272 | unsigned int reloc_size; |
| 3273 | if (sh_type == elfcpp::SHT_REL) |
| 3274 | reloc_size = elfcpp::Elf_sizes<32>::rel_size; |
| 3275 | else |
| 3276 | reloc_size = elfcpp::Elf_sizes<32>::rela_size; |
| 3277 | |
| 3278 | if (reloc_size != shdr.get_sh_entsize()) |
| 3279 | { |
| 3280 | // Ignore reloc section with unexpected entsize. The error |
| 3281 | // will be reported in the final link. |
| 3282 | continue; |
| 3283 | } |
| 3284 | |
| 3285 | size_t reloc_count = sh_size / reloc_size; |
| 3286 | if (static_cast<off_t>(reloc_count * reloc_size) != sh_size) |
| 3287 | { |
| 3288 | // Ignore reloc section with uneven size. The error will be |
| 3289 | // reported in the final link. |
| 3290 | continue; |
| 3291 | } |
| 3292 | |
| 3293 | gold_assert(output_offset != invalid_address |
| 3294 | || this->relocs_must_follow_section_writes()); |
| 3295 | |
| 3296 | // Get the section contents. This does work for the case in which |
| 3297 | // we modify the contents of an input section. We need to pass the |
| 3298 | // output view under such circumstances. |
| 3299 | section_size_type input_view_size = 0; |
| 3300 | const unsigned char* input_view = |
| 3301 | this->section_contents(index, &input_view_size, false); |
| 3302 | |
| 3303 | relinfo.reloc_shndx = i; |
| 3304 | relinfo.data_shndx = index; |
| 3305 | arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs, |
| 3306 | reloc_count, os, |
| 3307 | output_offset == invalid_address, |
| 3308 | input_view, |
| 3309 | os->address(), |
| 3310 | input_view_size); |
| 3311 | } |
| 3312 | |
| 3313 | // After we've done the relocations, we release the hash tables, |
| 3314 | // since we no longer need them. |
| 3315 | this->free_input_to_output_maps(); |
| 3316 | } |
| 3317 | |
| 3318 | // Count the local symbols. The ARM backend needs to know if a symbol |
| 3319 | // is a THUMB function or not. For global symbols, it is easy because |
| 3320 | // the Symbol object keeps the ELF symbol type. For local symbol it is |
| 3321 | // harder because we cannot access this information. So we override the |
| 3322 | // do_count_local_symbol in parent and scan local symbols to mark |
| 3323 | // THUMB functions. This is not the most efficient way but I do not want to |
| 3324 | // slow down other ports by calling a per symbol targer hook inside |
| 3325 | // Sized_relobj<size, big_endian>::do_count_local_symbols. |
| 3326 | |
| 3327 | template<bool big_endian> |
| 3328 | void |
| 3329 | Arm_relobj<big_endian>::do_count_local_symbols( |
| 3330 | Stringpool_template<char>* pool, |
| 3331 | Stringpool_template<char>* dynpool) |
| 3332 | { |
| 3333 | // We need to fix-up the values of any local symbols whose type are |
| 3334 | // STT_ARM_TFUNC. |
| 3335 | |
| 3336 | // Ask parent to count the local symbols. |
| 3337 | Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool); |
| 3338 | const unsigned int loccount = this->local_symbol_count(); |
| 3339 | if (loccount == 0) |
| 3340 | return; |
| 3341 | |
| 3342 | // Intialize the thumb function bit-vector. |
| 3343 | std::vector<bool> empty_vector(loccount, false); |
| 3344 | this->local_symbol_is_thumb_function_.swap(empty_vector); |
| 3345 | |
| 3346 | // Read the symbol table section header. |
| 3347 | const unsigned int symtab_shndx = this->symtab_shndx(); |
| 3348 | elfcpp::Shdr<32, big_endian> |
| 3349 | symtabshdr(this, this->elf_file()->section_header(symtab_shndx)); |
| 3350 | gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); |
| 3351 | |
| 3352 | // Read the local symbols. |
| 3353 | const int sym_size =elfcpp::Elf_sizes<32>::sym_size; |
| 3354 | gold_assert(loccount == symtabshdr.get_sh_info()); |
| 3355 | off_t locsize = loccount * sym_size; |
| 3356 | const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(), |
| 3357 | locsize, true, true); |
| 3358 | |
| 3359 | // Loop over the local symbols and mark any local symbols pointing |
| 3360 | // to THUMB functions. |
| 3361 | |
| 3362 | // Skip the first dummy symbol. |
| 3363 | psyms += sym_size; |
| 3364 | typename Sized_relobj<32, big_endian>::Local_values* plocal_values = |
| 3365 | this->local_values(); |
| 3366 | for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size) |
| 3367 | { |
| 3368 | elfcpp::Sym<32, big_endian> sym(psyms); |
| 3369 | elfcpp::STT st_type = sym.get_st_type(); |
| 3370 | Symbol_value<32>& lv((*plocal_values)[i]); |
| 3371 | Arm_address input_value = lv.input_value(); |
| 3372 | |
| 3373 | if (st_type == elfcpp::STT_ARM_TFUNC |
| 3374 | || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0))) |
| 3375 | { |
| 3376 | // This is a THUMB function. Mark this and canonicalize the |
| 3377 | // symbol value by setting LSB. |
| 3378 | this->local_symbol_is_thumb_function_[i] = true; |
| 3379 | if ((input_value & 1) == 0) |
| 3380 | lv.set_input_value(input_value | 1); |
| 3381 | } |
| 3382 | } |
| 3383 | } |
| 3384 | |
| 3385 | // Relocate sections. |
| 3386 | template<bool big_endian> |
| 3387 | void |
| 3388 | Arm_relobj<big_endian>::do_relocate_sections( |
| 3389 | const Symbol_table* symtab, |
| 3390 | const Layout* layout, |
| 3391 | const unsigned char* pshdrs, |
| 3392 | typename Sized_relobj<32, big_endian>::Views* pviews) |
| 3393 | { |
| 3394 | // Call parent to relocate sections. |
| 3395 | Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs, |
| 3396 | pviews); |
| 3397 | |
| 3398 | // We do not generate stubs if doing a relocatable link. |
| 3399 | if (parameters->options().relocatable()) |
| 3400 | return; |
| 3401 | |
| 3402 | // Relocate stub tables. |
| 3403 | unsigned int shnum = this->shnum(); |
| 3404 | |
| 3405 | Target_arm<big_endian>* arm_target = |
| 3406 | Target_arm<big_endian>::default_target(); |
| 3407 | |
| 3408 | Relocate_info<32, big_endian> relinfo; |
| 3409 | relinfo.symtab = symtab; |
| 3410 | relinfo.layout = layout; |
| 3411 | relinfo.object = this; |
| 3412 | |
| 3413 | for (unsigned int i = 1; i < shnum; ++i) |
| 3414 | { |
| 3415 | Arm_input_section<big_endian>* arm_input_section = |
| 3416 | arm_target->find_arm_input_section(this, i); |
| 3417 | |
| 3418 | if (arm_input_section == NULL |
| 3419 | || !arm_input_section->is_stub_table_owner() |
| 3420 | || arm_input_section->stub_table()->empty()) |
| 3421 | continue; |
| 3422 | |
| 3423 | // We cannot discard a section if it owns a stub table. |
| 3424 | Output_section* os = this->output_section(i); |
| 3425 | gold_assert(os != NULL); |
| 3426 | |
| 3427 | relinfo.reloc_shndx = elfcpp::SHN_UNDEF; |
| 3428 | relinfo.reloc_shdr = NULL; |
| 3429 | relinfo.data_shndx = i; |
| 3430 | relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size; |
| 3431 | |
| 3432 | gold_assert((*pviews)[i].view != NULL); |
| 3433 | |
| 3434 | // We are passed the output section view. Adjust it to cover the |
| 3435 | // stub table only. |
| 3436 | Stub_table<big_endian>* stub_table = arm_input_section->stub_table(); |
| 3437 | gold_assert((stub_table->address() >= (*pviews)[i].address) |
| 3438 | && ((stub_table->address() + stub_table->data_size()) |
| 3439 | <= (*pviews)[i].address + (*pviews)[i].view_size)); |
| 3440 | |
| 3441 | off_t offset = stub_table->address() - (*pviews)[i].address; |
| 3442 | unsigned char* view = (*pviews)[i].view + offset; |
| 3443 | Arm_address address = stub_table->address(); |
| 3444 | section_size_type view_size = stub_table->data_size(); |
| 3445 | |
| 3446 | stub_table->relocate_stubs(&relinfo, arm_target, os, view, address, |
| 3447 | view_size); |
| 3448 | } |
| 3449 | } |
| 3450 | |
| 3451 | // Read the symbol information. |
| 3452 | |
| 3453 | template<bool big_endian> |
| 3454 | void |
| 3455 | Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd) |
| 3456 | { |
| 3457 | // Call parent class to read symbol information. |
| 3458 | Sized_relobj<32, big_endian>::do_read_symbols(sd); |
| 3459 | |
| 3460 | // Read processor-specific flags in ELF file header. |
| 3461 | const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset, |
| 3462 | elfcpp::Elf_sizes<32>::ehdr_size, |
| 3463 | true, false); |
| 3464 | elfcpp::Ehdr<32, big_endian> ehdr(pehdr); |
| 3465 | this->processor_specific_flags_ = ehdr.get_e_flags(); |
| 3466 | } |
| 3467 | |
| 3468 | // Arm_dynobj methods. |
| 3469 | |
| 3470 | // Read the symbol information. |
| 3471 | |
| 3472 | template<bool big_endian> |
| 3473 | void |
| 3474 | Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd) |
| 3475 | { |
| 3476 | // Call parent class to read symbol information. |
| 3477 | Sized_dynobj<32, big_endian>::do_read_symbols(sd); |
| 3478 | |
| 3479 | // Read processor-specific flags in ELF file header. |
| 3480 | const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset, |
| 3481 | elfcpp::Elf_sizes<32>::ehdr_size, |
| 3482 | true, false); |
| 3483 | elfcpp::Ehdr<32, big_endian> ehdr(pehdr); |
| 3484 | this->processor_specific_flags_ = ehdr.get_e_flags(); |
| 3485 | } |
| 3486 | |
| 3487 | // Stub_addend_reader methods. |
| 3488 | |
| 3489 | // Read the addend of a REL relocation of type R_TYPE at VIEW. |
| 3490 | |
| 3491 | template<bool big_endian> |
| 3492 | elfcpp::Elf_types<32>::Elf_Swxword |
| 3493 | Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()( |
| 3494 | unsigned int r_type, |
| 3495 | const unsigned char* view, |
| 3496 | const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const |
| 3497 | { |
| 3498 | switch (r_type) |
| 3499 | { |
| 3500 | case elfcpp::R_ARM_CALL: |
| 3501 | case elfcpp::R_ARM_JUMP24: |
| 3502 | case elfcpp::R_ARM_PLT32: |
| 3503 | { |
| 3504 | typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype; |
| 3505 | const Valtype* wv = reinterpret_cast<const Valtype*>(view); |
| 3506 | Valtype val = elfcpp::Swap<32, big_endian>::readval(wv); |
| 3507 | return utils::sign_extend<26>(val << 2); |
| 3508 | } |
| 3509 | |
| 3510 | case elfcpp::R_ARM_THM_CALL: |
| 3511 | case elfcpp::R_ARM_THM_JUMP24: |
| 3512 | case elfcpp::R_ARM_THM_XPC22: |
| 3513 | { |
| 3514 | // Fetch the addend. We use the Thumb-2 encoding (backwards |
| 3515 | // compatible with Thumb-1) involving the J1 and J2 bits. |
| 3516 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 3517 | const Valtype* wv = reinterpret_cast<const Valtype*>(view); |
| 3518 | Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 3519 | Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 3520 | |
| 3521 | uint32_t s = (upper_insn & (1 << 10)) >> 10; |
| 3522 | uint32_t upper = upper_insn & 0x3ff; |
| 3523 | uint32_t lower = lower_insn & 0x7ff; |
| 3524 | uint32_t j1 = (lower_insn & (1 << 13)) >> 13; |
| 3525 | uint32_t j2 = (lower_insn & (1 << 11)) >> 11; |
| 3526 | uint32_t i1 = j1 ^ s ? 0 : 1; |
| 3527 | uint32_t i2 = j2 ^ s ? 0 : 1; |
| 3528 | |
| 3529 | return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22) |
| 3530 | | (upper << 12) | (lower << 1)); |
| 3531 | } |
| 3532 | |
| 3533 | case elfcpp::R_ARM_THM_JUMP19: |
| 3534 | { |
| 3535 | typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype; |
| 3536 | const Valtype* wv = reinterpret_cast<const Valtype*>(view); |
| 3537 | Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv); |
| 3538 | Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1); |
| 3539 | |
| 3540 | // Reconstruct the top three bits and squish the two 11 bit pieces |
| 3541 | // together. |
| 3542 | uint32_t S = (upper_insn & 0x0400) >> 10; |
| 3543 | uint32_t J1 = (lower_insn & 0x2000) >> 13; |
| 3544 | uint32_t J2 = (lower_insn & 0x0800) >> 11; |
| 3545 | uint32_t upper = |
| 3546 | (S << 8) | (J2 << 7) | (J1 << 6) | (upper_insn & 0x003f); |
| 3547 | uint32_t lower = (lower_insn & 0x07ff); |
| 3548 | return utils::sign_extend<23>((upper << 12) | (lower << 1)); |
| 3549 | } |
| 3550 | |
| 3551 | default: |
| 3552 | gold_unreachable(); |
| 3553 | } |
| 3554 | } |
| 3555 | |
| 3556 | // A class to handle the PLT data. |
| 3557 | |
| 3558 | template<bool big_endian> |
| 3559 | class Output_data_plt_arm : public Output_section_data |
| 3560 | { |
| 3561 | public: |
| 3562 | typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian> |
| 3563 | Reloc_section; |
| 3564 | |
| 3565 | Output_data_plt_arm(Layout*, Output_data_space*); |
| 3566 | |
| 3567 | // Add an entry to the PLT. |
| 3568 | void |
| 3569 | add_entry(Symbol* gsym); |
| 3570 | |
| 3571 | // Return the .rel.plt section data. |
| 3572 | const Reloc_section* |
| 3573 | rel_plt() const |
| 3574 | { return this->rel_; } |
| 3575 | |
| 3576 | protected: |
| 3577 | void |
| 3578 | do_adjust_output_section(Output_section* os); |
| 3579 | |
| 3580 | // Write to a map file. |
| 3581 | void |
| 3582 | do_print_to_mapfile(Mapfile* mapfile) const |
| 3583 | { mapfile->print_output_data(this, _("** PLT")); } |
| 3584 | |
| 3585 | private: |
| 3586 | // Template for the first PLT entry. |
| 3587 | static const uint32_t first_plt_entry[5]; |
| 3588 | |
| 3589 | // Template for subsequent PLT entries. |
| 3590 | static const uint32_t plt_entry[3]; |
| 3591 | |
| 3592 | // Set the final size. |
| 3593 | void |
| 3594 | set_final_data_size() |
| 3595 | { |
| 3596 | this->set_data_size(sizeof(first_plt_entry) |
| 3597 | + this->count_ * sizeof(plt_entry)); |
| 3598 | } |
| 3599 | |
| 3600 | // Write out the PLT data. |
| 3601 | void |
| 3602 | do_write(Output_file*); |
| 3603 | |
| 3604 | // The reloc section. |
| 3605 | Reloc_section* rel_; |
| 3606 | // The .got.plt section. |
| 3607 | Output_data_space* got_plt_; |
| 3608 | // The number of PLT entries. |
| 3609 | unsigned int count_; |
| 3610 | }; |
| 3611 | |
| 3612 | // Create the PLT section. The ordinary .got section is an argument, |
| 3613 | // since we need to refer to the start. We also create our own .got |
| 3614 | // section just for PLT entries. |
| 3615 | |
| 3616 | template<bool big_endian> |
| 3617 | Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout, |
| 3618 | Output_data_space* got_plt) |
| 3619 | : Output_section_data(4), got_plt_(got_plt), count_(0) |
| 3620 | { |
| 3621 | this->rel_ = new Reloc_section(false); |
| 3622 | layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL, |
| 3623 | elfcpp::SHF_ALLOC, this->rel_, true); |
| 3624 | } |
| 3625 | |
| 3626 | template<bool big_endian> |
| 3627 | void |
| 3628 | Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os) |
| 3629 | { |
| 3630 | os->set_entsize(0); |
| 3631 | } |
| 3632 | |
| 3633 | // Add an entry to the PLT. |
| 3634 | |
| 3635 | template<bool big_endian> |
| 3636 | void |
| 3637 | Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym) |
| 3638 | { |
| 3639 | gold_assert(!gsym->has_plt_offset()); |
| 3640 | |
| 3641 | // Note that when setting the PLT offset we skip the initial |
| 3642 | // reserved PLT entry. |
| 3643 | gsym->set_plt_offset((this->count_) * sizeof(plt_entry) |
| 3644 | + sizeof(first_plt_entry)); |
| 3645 | |
| 3646 | ++this->count_; |
| 3647 | |
| 3648 | section_offset_type got_offset = this->got_plt_->current_data_size(); |
| 3649 | |
| 3650 | // Every PLT entry needs a GOT entry which points back to the PLT |
| 3651 | // entry (this will be changed by the dynamic linker, normally |
| 3652 | // lazily when the function is called). |
| 3653 | this->got_plt_->set_current_data_size(got_offset + 4); |
| 3654 | |
| 3655 | // Every PLT entry needs a reloc. |
| 3656 | gsym->set_needs_dynsym_entry(); |
| 3657 | this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_, |
| 3658 | got_offset); |
| 3659 | |
| 3660 | // Note that we don't need to save the symbol. The contents of the |
| 3661 | // PLT are independent of which symbols are used. The symbols only |
| 3662 | // appear in the relocations. |
| 3663 | } |
| 3664 | |
| 3665 | // ARM PLTs. |
| 3666 | // FIXME: This is not very flexible. Right now this has only been tested |
| 3667 | // on armv5te. If we are to support additional architecture features like |
| 3668 | // Thumb-2 or BE8, we need to make this more flexible like GNU ld. |
| 3669 | |
| 3670 | // The first entry in the PLT. |
| 3671 | template<bool big_endian> |
| 3672 | const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] = |
| 3673 | { |
| 3674 | 0xe52de004, // str lr, [sp, #-4]! |
| 3675 | 0xe59fe004, // ldr lr, [pc, #4] |
| 3676 | 0xe08fe00e, // add lr, pc, lr |
| 3677 | 0xe5bef008, // ldr pc, [lr, #8]! |
| 3678 | 0x00000000, // &GOT[0] - . |
| 3679 | }; |
| 3680 | |
| 3681 | // Subsequent entries in the PLT. |
| 3682 | |
| 3683 | template<bool big_endian> |
| 3684 | const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] = |
| 3685 | { |
| 3686 | 0xe28fc600, // add ip, pc, #0xNN00000 |
| 3687 | 0xe28cca00, // add ip, ip, #0xNN000 |
| 3688 | 0xe5bcf000, // ldr pc, [ip, #0xNNN]! |
| 3689 | }; |
| 3690 | |
| 3691 | // Write out the PLT. This uses the hand-coded instructions above, |
| 3692 | // and adjusts them as needed. This is all specified by the arm ELF |
| 3693 | // Processor Supplement. |
| 3694 | |
| 3695 | template<bool big_endian> |
| 3696 | void |
| 3697 | Output_data_plt_arm<big_endian>::do_write(Output_file* of) |
| 3698 | { |
| 3699 | const off_t offset = this->offset(); |
| 3700 | const section_size_type oview_size = |
| 3701 | convert_to_section_size_type(this->data_size()); |
| 3702 | unsigned char* const oview = of->get_output_view(offset, oview_size); |
| 3703 | |
| 3704 | const off_t got_file_offset = this->got_plt_->offset(); |
| 3705 | const section_size_type got_size = |
| 3706 | convert_to_section_size_type(this->got_plt_->data_size()); |
| 3707 | unsigned char* const got_view = of->get_output_view(got_file_offset, |
| 3708 | got_size); |
| 3709 | unsigned char* pov = oview; |
| 3710 | |
| 3711 | Arm_address plt_address = this->address(); |
| 3712 | Arm_address got_address = this->got_plt_->address(); |
| 3713 | |
| 3714 | // Write first PLT entry. All but the last word are constants. |
| 3715 | const size_t num_first_plt_words = (sizeof(first_plt_entry) |
| 3716 | / sizeof(plt_entry[0])); |
| 3717 | for (size_t i = 0; i < num_first_plt_words - 1; i++) |
| 3718 | elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]); |
| 3719 | // Last word in first PLT entry is &GOT[0] - . |
| 3720 | elfcpp::Swap<32, big_endian>::writeval(pov + 16, |
| 3721 | got_address - (plt_address + 16)); |
| 3722 | pov += sizeof(first_plt_entry); |
| 3723 | |
| 3724 | unsigned char* got_pov = got_view; |
| 3725 | |
| 3726 | memset(got_pov, 0, 12); |
| 3727 | got_pov += 12; |
| 3728 | |
| 3729 | const int rel_size = elfcpp::Elf_sizes<32>::rel_size; |
| 3730 | unsigned int plt_offset = sizeof(first_plt_entry); |
| 3731 | unsigned int plt_rel_offset = 0; |
| 3732 | unsigned int got_offset = 12; |
| 3733 | const unsigned int count = this->count_; |
| 3734 | for (unsigned int i = 0; |
| 3735 | i < count; |
| 3736 | ++i, |
| 3737 | pov += sizeof(plt_entry), |
| 3738 | got_pov += 4, |
| 3739 | plt_offset += sizeof(plt_entry), |
| 3740 | plt_rel_offset += rel_size, |
| 3741 | got_offset += 4) |
| 3742 | { |
| 3743 | // Set and adjust the PLT entry itself. |
| 3744 | int32_t offset = ((got_address + got_offset) |
| 3745 | - (plt_address + plt_offset + 8)); |
| 3746 | |
| 3747 | gold_assert(offset >= 0 && offset < 0x0fffffff); |
| 3748 | uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff); |
| 3749 | elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0); |
| 3750 | uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff); |
| 3751 | elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1); |
| 3752 | uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff); |
| 3753 | elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2); |
| 3754 | |
| 3755 | // Set the entry in the GOT. |
| 3756 | elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address); |
| 3757 | } |
| 3758 | |
| 3759 | gold_assert(static_cast<section_size_type>(pov - oview) == oview_size); |
| 3760 | gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size); |
| 3761 | |
| 3762 | of->write_output_view(offset, oview_size, oview); |
| 3763 | of->write_output_view(got_file_offset, got_size, got_view); |
| 3764 | } |
| 3765 | |
| 3766 | // Create a PLT entry for a global symbol. |
| 3767 | |
| 3768 | template<bool big_endian> |
| 3769 | void |
| 3770 | Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout, |
| 3771 | Symbol* gsym) |
| 3772 | { |
| 3773 | if (gsym->has_plt_offset()) |
| 3774 | return; |
| 3775 | |
| 3776 | if (this->plt_ == NULL) |
| 3777 | { |
| 3778 | // Create the GOT sections first. |
| 3779 | this->got_section(symtab, layout); |
| 3780 | |
| 3781 | this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_); |
| 3782 | layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS, |
| 3783 | (elfcpp::SHF_ALLOC |
| 3784 | | elfcpp::SHF_EXECINSTR), |
| 3785 | this->plt_, false); |
| 3786 | } |
| 3787 | this->plt_->add_entry(gsym); |
| 3788 | } |
| 3789 | |
| 3790 | // Report an unsupported relocation against a local symbol. |
| 3791 | |
| 3792 | template<bool big_endian> |
| 3793 | void |
| 3794 | Target_arm<big_endian>::Scan::unsupported_reloc_local( |
| 3795 | Sized_relobj<32, big_endian>* object, |
| 3796 | unsigned int r_type) |
| 3797 | { |
| 3798 | gold_error(_("%s: unsupported reloc %u against local symbol"), |
| 3799 | object->name().c_str(), r_type); |
| 3800 | } |
| 3801 | |
| 3802 | // We are about to emit a dynamic relocation of type R_TYPE. If the |
| 3803 | // dynamic linker does not support it, issue an error. The GNU linker |
| 3804 | // only issues a non-PIC error for an allocated read-only section. |
| 3805 | // Here we know the section is allocated, but we don't know that it is |
| 3806 | // read-only. But we check for all the relocation types which the |
| 3807 | // glibc dynamic linker supports, so it seems appropriate to issue an |
| 3808 | // error even if the section is not read-only. |
| 3809 | |
| 3810 | template<bool big_endian> |
| 3811 | void |
| 3812 | Target_arm<big_endian>::Scan::check_non_pic(Relobj* object, |
| 3813 | unsigned int r_type) |
| 3814 | { |
| 3815 | switch (r_type) |
| 3816 | { |
| 3817 | // These are the relocation types supported by glibc for ARM. |
| 3818 | case elfcpp::R_ARM_RELATIVE: |
| 3819 | case elfcpp::R_ARM_COPY: |
| 3820 | case elfcpp::R_ARM_GLOB_DAT: |
| 3821 | case elfcpp::R_ARM_JUMP_SLOT: |
| 3822 | case elfcpp::R_ARM_ABS32: |
| 3823 | case elfcpp::R_ARM_ABS32_NOI: |
| 3824 | case elfcpp::R_ARM_PC24: |
| 3825 | // FIXME: The following 3 types are not supported by Android's dynamic |
| 3826 | // linker. |
| 3827 | case elfcpp::R_ARM_TLS_DTPMOD32: |
| 3828 | case elfcpp::R_ARM_TLS_DTPOFF32: |
| 3829 | case elfcpp::R_ARM_TLS_TPOFF32: |
| 3830 | return; |
| 3831 | |
| 3832 | default: |
| 3833 | // This prevents us from issuing more than one error per reloc |
| 3834 | // section. But we can still wind up issuing more than one |
| 3835 | // error per object file. |
| 3836 | if (this->issued_non_pic_error_) |
| 3837 | return; |
| 3838 | object->error(_("requires unsupported dynamic reloc; " |
| 3839 | "recompile with -fPIC")); |
| 3840 | this->issued_non_pic_error_ = true; |
| 3841 | return; |
| 3842 | |
| 3843 | case elfcpp::R_ARM_NONE: |
| 3844 | gold_unreachable(); |
| 3845 | } |
| 3846 | } |
| 3847 | |
| 3848 | // Scan a relocation for a local symbol. |
| 3849 | // FIXME: This only handles a subset of relocation types used by Android |
| 3850 | // on ARM v5te devices. |
| 3851 | |
| 3852 | template<bool big_endian> |
| 3853 | inline void |
| 3854 | Target_arm<big_endian>::Scan::local(Symbol_table* symtab, |
| 3855 | Layout* layout, |
| 3856 | Target_arm* target, |
| 3857 | Sized_relobj<32, big_endian>* object, |
| 3858 | unsigned int data_shndx, |
| 3859 | Output_section* output_section, |
| 3860 | const elfcpp::Rel<32, big_endian>& reloc, |
| 3861 | unsigned int r_type, |
| 3862 | const elfcpp::Sym<32, big_endian>&) |
| 3863 | { |
| 3864 | r_type = get_real_reloc_type(r_type); |
| 3865 | switch (r_type) |
| 3866 | { |
| 3867 | case elfcpp::R_ARM_NONE: |
| 3868 | break; |
| 3869 | |
| 3870 | case elfcpp::R_ARM_ABS32: |
| 3871 | case elfcpp::R_ARM_ABS32_NOI: |
| 3872 | // If building a shared library (or a position-independent |
| 3873 | // executable), we need to create a dynamic relocation for |
| 3874 | // this location. The relocation applied at link time will |
| 3875 | // apply the link-time value, so we flag the location with |
| 3876 | // an R_ARM_RELATIVE relocation so the dynamic loader can |
| 3877 | // relocate it easily. |
| 3878 | if (parameters->options().output_is_position_independent()) |
| 3879 | { |
| 3880 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 3881 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); |
| 3882 | // If we are to add more other reloc types than R_ARM_ABS32, |
| 3883 | // we need to add check_non_pic(object, r_type) here. |
| 3884 | rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE, |
| 3885 | output_section, data_shndx, |
| 3886 | reloc.get_r_offset()); |
| 3887 | } |
| 3888 | break; |
| 3889 | |
| 3890 | case elfcpp::R_ARM_REL32: |
| 3891 | case elfcpp::R_ARM_THM_CALL: |
| 3892 | case elfcpp::R_ARM_CALL: |
| 3893 | case elfcpp::R_ARM_PREL31: |
| 3894 | case elfcpp::R_ARM_JUMP24: |
| 3895 | case elfcpp::R_ARM_PLT32: |
| 3896 | case elfcpp::R_ARM_THM_ABS5: |
| 3897 | case elfcpp::R_ARM_ABS8: |
| 3898 | case elfcpp::R_ARM_ABS12: |
| 3899 | case elfcpp::R_ARM_ABS16: |
| 3900 | case elfcpp::R_ARM_BASE_ABS: |
| 3901 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 3902 | case elfcpp::R_ARM_MOVT_ABS: |
| 3903 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 3904 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 3905 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 3906 | case elfcpp::R_ARM_MOVT_PREL: |
| 3907 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 3908 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 3909 | break; |
| 3910 | |
| 3911 | case elfcpp::R_ARM_GOTOFF32: |
| 3912 | // We need a GOT section: |
| 3913 | target->got_section(symtab, layout); |
| 3914 | break; |
| 3915 | |
| 3916 | case elfcpp::R_ARM_BASE_PREL: |
| 3917 | // FIXME: What about this? |
| 3918 | break; |
| 3919 | |
| 3920 | case elfcpp::R_ARM_GOT_BREL: |
| 3921 | case elfcpp::R_ARM_GOT_PREL: |
| 3922 | { |
| 3923 | // The symbol requires a GOT entry. |
| 3924 | Output_data_got<32, big_endian>* got = |
| 3925 | target->got_section(symtab, layout); |
| 3926 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); |
| 3927 | if (got->add_local(object, r_sym, GOT_TYPE_STANDARD)) |
| 3928 | { |
| 3929 | // If we are generating a shared object, we need to add a |
| 3930 | // dynamic RELATIVE relocation for this symbol's GOT entry. |
| 3931 | if (parameters->options().output_is_position_independent()) |
| 3932 | { |
| 3933 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 3934 | unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); |
| 3935 | rel_dyn->add_local_relative( |
| 3936 | object, r_sym, elfcpp::R_ARM_RELATIVE, got, |
| 3937 | object->local_got_offset(r_sym, GOT_TYPE_STANDARD)); |
| 3938 | } |
| 3939 | } |
| 3940 | } |
| 3941 | break; |
| 3942 | |
| 3943 | case elfcpp::R_ARM_TARGET1: |
| 3944 | // This should have been mapped to another type already. |
| 3945 | // Fall through. |
| 3946 | case elfcpp::R_ARM_COPY: |
| 3947 | case elfcpp::R_ARM_GLOB_DAT: |
| 3948 | case elfcpp::R_ARM_JUMP_SLOT: |
| 3949 | case elfcpp::R_ARM_RELATIVE: |
| 3950 | // These are relocations which should only be seen by the |
| 3951 | // dynamic linker, and should never be seen here. |
| 3952 | gold_error(_("%s: unexpected reloc %u in object file"), |
| 3953 | object->name().c_str(), r_type); |
| 3954 | break; |
| 3955 | |
| 3956 | default: |
| 3957 | unsupported_reloc_local(object, r_type); |
| 3958 | break; |
| 3959 | } |
| 3960 | } |
| 3961 | |
| 3962 | // Report an unsupported relocation against a global symbol. |
| 3963 | |
| 3964 | template<bool big_endian> |
| 3965 | void |
| 3966 | Target_arm<big_endian>::Scan::unsupported_reloc_global( |
| 3967 | Sized_relobj<32, big_endian>* object, |
| 3968 | unsigned int r_type, |
| 3969 | Symbol* gsym) |
| 3970 | { |
| 3971 | gold_error(_("%s: unsupported reloc %u against global symbol %s"), |
| 3972 | object->name().c_str(), r_type, gsym->demangled_name().c_str()); |
| 3973 | } |
| 3974 | |
| 3975 | // Scan a relocation for a global symbol. |
| 3976 | // FIXME: This only handles a subset of relocation types used by Android |
| 3977 | // on ARM v5te devices. |
| 3978 | |
| 3979 | template<bool big_endian> |
| 3980 | inline void |
| 3981 | Target_arm<big_endian>::Scan::global(Symbol_table* symtab, |
| 3982 | Layout* layout, |
| 3983 | Target_arm* target, |
| 3984 | Sized_relobj<32, big_endian>* object, |
| 3985 | unsigned int data_shndx, |
| 3986 | Output_section* output_section, |
| 3987 | const elfcpp::Rel<32, big_endian>& reloc, |
| 3988 | unsigned int r_type, |
| 3989 | Symbol* gsym) |
| 3990 | { |
| 3991 | r_type = get_real_reloc_type(r_type); |
| 3992 | switch (r_type) |
| 3993 | { |
| 3994 | case elfcpp::R_ARM_NONE: |
| 3995 | break; |
| 3996 | |
| 3997 | case elfcpp::R_ARM_ABS32: |
| 3998 | case elfcpp::R_ARM_ABS32_NOI: |
| 3999 | { |
| 4000 | // Make a dynamic relocation if necessary. |
| 4001 | if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF)) |
| 4002 | { |
| 4003 | if (target->may_need_copy_reloc(gsym)) |
| 4004 | { |
| 4005 | target->copy_reloc(symtab, layout, object, |
| 4006 | data_shndx, output_section, gsym, reloc); |
| 4007 | } |
| 4008 | else if (gsym->can_use_relative_reloc(false)) |
| 4009 | { |
| 4010 | // If we are to add more other reloc types than R_ARM_ABS32, |
| 4011 | // we need to add check_non_pic(object, r_type) here. |
| 4012 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 4013 | rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE, |
| 4014 | output_section, object, |
| 4015 | data_shndx, reloc.get_r_offset()); |
| 4016 | } |
| 4017 | else |
| 4018 | { |
| 4019 | // If we are to add more other reloc types than R_ARM_ABS32, |
| 4020 | // we need to add check_non_pic(object, r_type) here. |
| 4021 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 4022 | rel_dyn->add_global(gsym, r_type, output_section, object, |
| 4023 | data_shndx, reloc.get_r_offset()); |
| 4024 | } |
| 4025 | } |
| 4026 | } |
| 4027 | break; |
| 4028 | |
| 4029 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 4030 | case elfcpp::R_ARM_MOVT_ABS: |
| 4031 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 4032 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 4033 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 4034 | case elfcpp::R_ARM_MOVT_PREL: |
| 4035 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 4036 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 4037 | break; |
| 4038 | |
| 4039 | case elfcpp::R_ARM_THM_ABS5: |
| 4040 | case elfcpp::R_ARM_ABS8: |
| 4041 | case elfcpp::R_ARM_ABS12: |
| 4042 | case elfcpp::R_ARM_ABS16: |
| 4043 | case elfcpp::R_ARM_BASE_ABS: |
| 4044 | { |
| 4045 | // No dynamic relocs of this kinds. |
| 4046 | // Report the error in case of PIC. |
| 4047 | int flags = Symbol::NON_PIC_REF; |
| 4048 | if (gsym->type() == elfcpp::STT_FUNC |
| 4049 | || gsym->type() == elfcpp::STT_ARM_TFUNC) |
| 4050 | flags |= Symbol::FUNCTION_CALL; |
| 4051 | if (gsym->needs_dynamic_reloc(flags)) |
| 4052 | check_non_pic(object, r_type); |
| 4053 | } |
| 4054 | break; |
| 4055 | |
| 4056 | case elfcpp::R_ARM_REL32: |
| 4057 | case elfcpp::R_ARM_PREL31: |
| 4058 | { |
| 4059 | // Make a dynamic relocation if necessary. |
| 4060 | int flags = Symbol::NON_PIC_REF; |
| 4061 | if (gsym->needs_dynamic_reloc(flags)) |
| 4062 | { |
| 4063 | if (target->may_need_copy_reloc(gsym)) |
| 4064 | { |
| 4065 | target->copy_reloc(symtab, layout, object, |
| 4066 | data_shndx, output_section, gsym, reloc); |
| 4067 | } |
| 4068 | else |
| 4069 | { |
| 4070 | check_non_pic(object, r_type); |
| 4071 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 4072 | rel_dyn->add_global(gsym, r_type, output_section, object, |
| 4073 | data_shndx, reloc.get_r_offset()); |
| 4074 | } |
| 4075 | } |
| 4076 | } |
| 4077 | break; |
| 4078 | |
| 4079 | case elfcpp::R_ARM_JUMP24: |
| 4080 | case elfcpp::R_ARM_THM_CALL: |
| 4081 | case elfcpp::R_ARM_CALL: |
| 4082 | { |
| 4083 | if (Target_arm<big_endian>::Scan::symbol_needs_plt_entry(gsym)) |
| 4084 | target->make_plt_entry(symtab, layout, gsym); |
| 4085 | // Make a dynamic relocation if necessary. |
| 4086 | int flags = Symbol::NON_PIC_REF; |
| 4087 | if (gsym->type() == elfcpp::STT_FUNC |
| 4088 | || gsym->type() == elfcpp::STT_ARM_TFUNC) |
| 4089 | flags |= Symbol::FUNCTION_CALL; |
| 4090 | if (gsym->needs_dynamic_reloc(flags)) |
| 4091 | { |
| 4092 | if (target->may_need_copy_reloc(gsym)) |
| 4093 | { |
| 4094 | target->copy_reloc(symtab, layout, object, |
| 4095 | data_shndx, output_section, gsym, |
| 4096 | reloc); |
| 4097 | } |
| 4098 | else |
| 4099 | { |
| 4100 | check_non_pic(object, r_type); |
| 4101 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 4102 | rel_dyn->add_global(gsym, r_type, output_section, object, |
| 4103 | data_shndx, reloc.get_r_offset()); |
| 4104 | } |
| 4105 | } |
| 4106 | } |
| 4107 | break; |
| 4108 | |
| 4109 | case elfcpp::R_ARM_PLT32: |
| 4110 | // If the symbol is fully resolved, this is just a relative |
| 4111 | // local reloc. Otherwise we need a PLT entry. |
| 4112 | if (gsym->final_value_is_known()) |
| 4113 | break; |
| 4114 | // If building a shared library, we can also skip the PLT entry |
| 4115 | // if the symbol is defined in the output file and is protected |
| 4116 | // or hidden. |
| 4117 | if (gsym->is_defined() |
| 4118 | && !gsym->is_from_dynobj() |
| 4119 | && !gsym->is_preemptible()) |
| 4120 | break; |
| 4121 | target->make_plt_entry(symtab, layout, gsym); |
| 4122 | break; |
| 4123 | |
| 4124 | case elfcpp::R_ARM_GOTOFF32: |
| 4125 | // We need a GOT section. |
| 4126 | target->got_section(symtab, layout); |
| 4127 | break; |
| 4128 | |
| 4129 | case elfcpp::R_ARM_BASE_PREL: |
| 4130 | // FIXME: What about this? |
| 4131 | break; |
| 4132 | |
| 4133 | case elfcpp::R_ARM_GOT_BREL: |
| 4134 | case elfcpp::R_ARM_GOT_PREL: |
| 4135 | { |
| 4136 | // The symbol requires a GOT entry. |
| 4137 | Output_data_got<32, big_endian>* got = |
| 4138 | target->got_section(symtab, layout); |
| 4139 | if (gsym->final_value_is_known()) |
| 4140 | got->add_global(gsym, GOT_TYPE_STANDARD); |
| 4141 | else |
| 4142 | { |
| 4143 | // If this symbol is not fully resolved, we need to add a |
| 4144 | // GOT entry with a dynamic relocation. |
| 4145 | Reloc_section* rel_dyn = target->rel_dyn_section(layout); |
| 4146 | if (gsym->is_from_dynobj() |
| 4147 | || gsym->is_undefined() |
| 4148 | || gsym->is_preemptible()) |
| 4149 | got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, |
| 4150 | rel_dyn, elfcpp::R_ARM_GLOB_DAT); |
| 4151 | else |
| 4152 | { |
| 4153 | if (got->add_global(gsym, GOT_TYPE_STANDARD)) |
| 4154 | rel_dyn->add_global_relative( |
| 4155 | gsym, elfcpp::R_ARM_RELATIVE, got, |
| 4156 | gsym->got_offset(GOT_TYPE_STANDARD)); |
| 4157 | } |
| 4158 | } |
| 4159 | } |
| 4160 | break; |
| 4161 | |
| 4162 | case elfcpp::R_ARM_TARGET1: |
| 4163 | // This should have been mapped to another type already. |
| 4164 | // Fall through. |
| 4165 | case elfcpp::R_ARM_COPY: |
| 4166 | case elfcpp::R_ARM_GLOB_DAT: |
| 4167 | case elfcpp::R_ARM_JUMP_SLOT: |
| 4168 | case elfcpp::R_ARM_RELATIVE: |
| 4169 | // These are relocations which should only be seen by the |
| 4170 | // dynamic linker, and should never be seen here. |
| 4171 | gold_error(_("%s: unexpected reloc %u in object file"), |
| 4172 | object->name().c_str(), r_type); |
| 4173 | break; |
| 4174 | |
| 4175 | default: |
| 4176 | unsupported_reloc_global(object, r_type, gsym); |
| 4177 | break; |
| 4178 | } |
| 4179 | } |
| 4180 | |
| 4181 | // Process relocations for gc. |
| 4182 | |
| 4183 | template<bool big_endian> |
| 4184 | void |
| 4185 | Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab, |
| 4186 | Layout* layout, |
| 4187 | Sized_relobj<32, big_endian>* object, |
| 4188 | unsigned int data_shndx, |
| 4189 | unsigned int, |
| 4190 | const unsigned char* prelocs, |
| 4191 | size_t reloc_count, |
| 4192 | Output_section* output_section, |
| 4193 | bool needs_special_offset_handling, |
| 4194 | size_t local_symbol_count, |
| 4195 | const unsigned char* plocal_symbols) |
| 4196 | { |
| 4197 | typedef Target_arm<big_endian> Arm; |
| 4198 | typedef typename Target_arm<big_endian>::Scan Scan; |
| 4199 | |
| 4200 | gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>( |
| 4201 | symtab, |
| 4202 | layout, |
| 4203 | this, |
| 4204 | object, |
| 4205 | data_shndx, |
| 4206 | prelocs, |
| 4207 | reloc_count, |
| 4208 | output_section, |
| 4209 | needs_special_offset_handling, |
| 4210 | local_symbol_count, |
| 4211 | plocal_symbols); |
| 4212 | } |
| 4213 | |
| 4214 | // Scan relocations for a section. |
| 4215 | |
| 4216 | template<bool big_endian> |
| 4217 | void |
| 4218 | Target_arm<big_endian>::scan_relocs(Symbol_table* symtab, |
| 4219 | Layout* layout, |
| 4220 | Sized_relobj<32, big_endian>* object, |
| 4221 | unsigned int data_shndx, |
| 4222 | unsigned int sh_type, |
| 4223 | const unsigned char* prelocs, |
| 4224 | size_t reloc_count, |
| 4225 | Output_section* output_section, |
| 4226 | bool needs_special_offset_handling, |
| 4227 | size_t local_symbol_count, |
| 4228 | const unsigned char* plocal_symbols) |
| 4229 | { |
| 4230 | typedef typename Target_arm<big_endian>::Scan Scan; |
| 4231 | if (sh_type == elfcpp::SHT_RELA) |
| 4232 | { |
| 4233 | gold_error(_("%s: unsupported RELA reloc section"), |
| 4234 | object->name().c_str()); |
| 4235 | return; |
| 4236 | } |
| 4237 | |
| 4238 | gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>( |
| 4239 | symtab, |
| 4240 | layout, |
| 4241 | this, |
| 4242 | object, |
| 4243 | data_shndx, |
| 4244 | prelocs, |
| 4245 | reloc_count, |
| 4246 | output_section, |
| 4247 | needs_special_offset_handling, |
| 4248 | local_symbol_count, |
| 4249 | plocal_symbols); |
| 4250 | } |
| 4251 | |
| 4252 | // Finalize the sections. |
| 4253 | |
| 4254 | template<bool big_endian> |
| 4255 | void |
| 4256 | Target_arm<big_endian>::do_finalize_sections( |
| 4257 | Layout* layout, |
| 4258 | const Input_objects* input_objects) |
| 4259 | { |
| 4260 | // Merge processor-specific flags. |
| 4261 | for (Input_objects::Relobj_iterator p = input_objects->relobj_begin(); |
| 4262 | p != input_objects->relobj_end(); |
| 4263 | ++p) |
| 4264 | { |
| 4265 | Arm_relobj<big_endian>* arm_relobj = |
| 4266 | Arm_relobj<big_endian>::as_arm_relobj(*p); |
| 4267 | this->merge_processor_specific_flags( |
| 4268 | arm_relobj->name(), |
| 4269 | arm_relobj->processor_specific_flags()); |
| 4270 | } |
| 4271 | |
| 4272 | for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin(); |
| 4273 | p != input_objects->dynobj_end(); |
| 4274 | ++p) |
| 4275 | { |
| 4276 | Arm_dynobj<big_endian>* arm_dynobj = |
| 4277 | Arm_dynobj<big_endian>::as_arm_dynobj(*p); |
| 4278 | this->merge_processor_specific_flags( |
| 4279 | arm_dynobj->name(), |
| 4280 | arm_dynobj->processor_specific_flags()); |
| 4281 | } |
| 4282 | |
| 4283 | // Fill in some more dynamic tags. |
| 4284 | Output_data_dynamic* const odyn = layout->dynamic_data(); |
| 4285 | if (odyn != NULL) |
| 4286 | { |
| 4287 | if (this->got_plt_ != NULL |
| 4288 | && this->got_plt_->output_section() != NULL) |
| 4289 | odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_); |
| 4290 | |
| 4291 | if (this->plt_ != NULL |
| 4292 | && this->plt_->output_section() != NULL) |
| 4293 | { |
| 4294 | const Output_data* od = this->plt_->rel_plt(); |
| 4295 | odyn->add_section_size(elfcpp::DT_PLTRELSZ, od); |
| 4296 | odyn->add_section_address(elfcpp::DT_JMPREL, od); |
| 4297 | odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL); |
| 4298 | } |
| 4299 | |
| 4300 | if (this->rel_dyn_ != NULL |
| 4301 | && this->rel_dyn_->output_section() != NULL) |
| 4302 | { |
| 4303 | const Output_data* od = this->rel_dyn_; |
| 4304 | odyn->add_section_address(elfcpp::DT_REL, od); |
| 4305 | odyn->add_section_size(elfcpp::DT_RELSZ, od); |
| 4306 | odyn->add_constant(elfcpp::DT_RELENT, |
| 4307 | elfcpp::Elf_sizes<32>::rel_size); |
| 4308 | } |
| 4309 | |
| 4310 | if (!parameters->options().shared()) |
| 4311 | { |
| 4312 | // The value of the DT_DEBUG tag is filled in by the dynamic |
| 4313 | // linker at run time, and used by the debugger. |
| 4314 | odyn->add_constant(elfcpp::DT_DEBUG, 0); |
| 4315 | } |
| 4316 | } |
| 4317 | |
| 4318 | // Emit any relocs we saved in an attempt to avoid generating COPY |
| 4319 | // relocs. |
| 4320 | if (this->copy_relocs_.any_saved_relocs()) |
| 4321 | this->copy_relocs_.emit(this->rel_dyn_section(layout)); |
| 4322 | |
| 4323 | // For the ARM target, we need to add a PT_ARM_EXIDX segment for |
| 4324 | // the .ARM.exidx section. |
| 4325 | if (!layout->script_options()->saw_phdrs_clause() |
| 4326 | && !parameters->options().relocatable()) |
| 4327 | { |
| 4328 | Output_section* exidx_section = |
| 4329 | layout->find_output_section(".ARM.exidx"); |
| 4330 | |
| 4331 | if (exidx_section != NULL |
| 4332 | && exidx_section->type() == elfcpp::SHT_ARM_EXIDX) |
| 4333 | { |
| 4334 | gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0) |
| 4335 | == NULL); |
| 4336 | Output_segment* exidx_segment = |
| 4337 | layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R); |
| 4338 | exidx_segment->add_output_section(exidx_section, elfcpp::PF_R, |
| 4339 | false); |
| 4340 | } |
| 4341 | } |
| 4342 | } |
| 4343 | |
| 4344 | // Return whether a direct absolute static relocation needs to be applied. |
| 4345 | // In cases where Scan::local() or Scan::global() has created |
| 4346 | // a dynamic relocation other than R_ARM_RELATIVE, the addend |
| 4347 | // of the relocation is carried in the data, and we must not |
| 4348 | // apply the static relocation. |
| 4349 | |
| 4350 | template<bool big_endian> |
| 4351 | inline bool |
| 4352 | Target_arm<big_endian>::Relocate::should_apply_static_reloc( |
| 4353 | const Sized_symbol<32>* gsym, |
| 4354 | int ref_flags, |
| 4355 | bool is_32bit, |
| 4356 | Output_section* output_section) |
| 4357 | { |
| 4358 | // If the output section is not allocated, then we didn't call |
| 4359 | // scan_relocs, we didn't create a dynamic reloc, and we must apply |
| 4360 | // the reloc here. |
| 4361 | if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0) |
| 4362 | return true; |
| 4363 | |
| 4364 | // For local symbols, we will have created a non-RELATIVE dynamic |
| 4365 | // relocation only if (a) the output is position independent, |
| 4366 | // (b) the relocation is absolute (not pc- or segment-relative), and |
| 4367 | // (c) the relocation is not 32 bits wide. |
| 4368 | if (gsym == NULL) |
| 4369 | return !(parameters->options().output_is_position_independent() |
| 4370 | && (ref_flags & Symbol::ABSOLUTE_REF) |
| 4371 | && !is_32bit); |
| 4372 | |
| 4373 | // For global symbols, we use the same helper routines used in the |
| 4374 | // scan pass. If we did not create a dynamic relocation, or if we |
| 4375 | // created a RELATIVE dynamic relocation, we should apply the static |
| 4376 | // relocation. |
| 4377 | bool has_dyn = gsym->needs_dynamic_reloc(ref_flags); |
| 4378 | bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF) |
| 4379 | && gsym->can_use_relative_reloc(ref_flags |
| 4380 | & Symbol::FUNCTION_CALL); |
| 4381 | return !has_dyn || is_rel; |
| 4382 | } |
| 4383 | |
| 4384 | // Perform a relocation. |
| 4385 | |
| 4386 | template<bool big_endian> |
| 4387 | inline bool |
| 4388 | Target_arm<big_endian>::Relocate::relocate( |
| 4389 | const Relocate_info<32, big_endian>* relinfo, |
| 4390 | Target_arm* target, |
| 4391 | Output_section *output_section, |
| 4392 | size_t relnum, |
| 4393 | const elfcpp::Rel<32, big_endian>& rel, |
| 4394 | unsigned int r_type, |
| 4395 | const Sized_symbol<32>* gsym, |
| 4396 | const Symbol_value<32>* psymval, |
| 4397 | unsigned char* view, |
| 4398 | Arm_address address, |
| 4399 | section_size_type /* view_size */ ) |
| 4400 | { |
| 4401 | typedef Arm_relocate_functions<big_endian> Arm_relocate_functions; |
| 4402 | |
| 4403 | r_type = get_real_reloc_type(r_type); |
| 4404 | |
| 4405 | const Arm_relobj<big_endian>* object = |
| 4406 | Arm_relobj<big_endian>::as_arm_relobj(relinfo->object); |
| 4407 | |
| 4408 | // If the final branch target of a relocation is THUMB instruction, this |
| 4409 | // is 1. Otherwise it is 0. |
| 4410 | Arm_address thumb_bit = 0; |
| 4411 | Symbol_value<32> symval; |
| 4412 | if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs) |
| 4413 | { |
| 4414 | if (gsym != NULL) |
| 4415 | { |
| 4416 | // This is a global symbol. Determine if we use PLT and if the |
| 4417 | // final target is THUMB. |
| 4418 | if (gsym->use_plt_offset(reloc_is_non_pic(r_type))) |
| 4419 | { |
| 4420 | // This uses a PLT, change the symbol value. |
| 4421 | symval.set_output_value(target->plt_section()->address() |
| 4422 | + gsym->plt_offset()); |
| 4423 | psymval = &symval; |
| 4424 | } |
| 4425 | else |
| 4426 | { |
| 4427 | // Set thumb bit if symbol: |
| 4428 | // -Has type STT_ARM_TFUNC or |
| 4429 | // -Has type STT_FUNC, is defined and with LSB in value set. |
| 4430 | thumb_bit = |
| 4431 | (((gsym->type() == elfcpp::STT_ARM_TFUNC) |
| 4432 | || (gsym->type() == elfcpp::STT_FUNC |
| 4433 | && !gsym->is_undefined() |
| 4434 | && ((psymval->value(object, 0) & 1) != 0))) |
| 4435 | ? 1 |
| 4436 | : 0); |
| 4437 | } |
| 4438 | } |
| 4439 | else |
| 4440 | { |
| 4441 | // This is a local symbol. Determine if the final target is THUMB. |
| 4442 | // We saved this information when all the local symbols were read. |
| 4443 | elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info(); |
| 4444 | unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info); |
| 4445 | thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0; |
| 4446 | } |
| 4447 | } |
| 4448 | else |
| 4449 | { |
| 4450 | // This is a fake relocation synthesized for a stub. It does not have |
| 4451 | // a real symbol. We just look at the LSB of the symbol value to |
| 4452 | // determine if the target is THUMB or not. |
| 4453 | thumb_bit = ((psymval->value(object, 0) & 1) != 0); |
| 4454 | } |
| 4455 | |
| 4456 | // Strip LSB if this points to a THUMB target. |
| 4457 | if (thumb_bit != 0 |
| 4458 | && Target_arm<big_endian>::reloc_uses_thumb_bit(r_type) |
| 4459 | && ((psymval->value(object, 0) & 1) != 0)) |
| 4460 | { |
| 4461 | Arm_address stripped_value = |
| 4462 | psymval->value(object, 0) & ~static_cast<Arm_address>(1); |
| 4463 | symval.set_output_value(stripped_value); |
| 4464 | psymval = &symval; |
| 4465 | } |
| 4466 | |
| 4467 | // Get the GOT offset if needed. |
| 4468 | // The GOT pointer points to the end of the GOT section. |
| 4469 | // We need to subtract the size of the GOT section to get |
| 4470 | // the actual offset to use in the relocation. |
| 4471 | bool have_got_offset = false; |
| 4472 | unsigned int got_offset = 0; |
| 4473 | switch (r_type) |
| 4474 | { |
| 4475 | case elfcpp::R_ARM_GOT_BREL: |
| 4476 | case elfcpp::R_ARM_GOT_PREL: |
| 4477 | if (gsym != NULL) |
| 4478 | { |
| 4479 | gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD)); |
| 4480 | got_offset = (gsym->got_offset(GOT_TYPE_STANDARD) |
| 4481 | - target->got_size()); |
| 4482 | } |
| 4483 | else |
| 4484 | { |
| 4485 | unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info()); |
| 4486 | gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD)); |
| 4487 | got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD) |
| 4488 | - target->got_size()); |
| 4489 | } |
| 4490 | have_got_offset = true; |
| 4491 | break; |
| 4492 | |
| 4493 | default: |
| 4494 | break; |
| 4495 | } |
| 4496 | |
| 4497 | typename Arm_relocate_functions::Status reloc_status = |
| 4498 | Arm_relocate_functions::STATUS_OKAY; |
| 4499 | switch (r_type) |
| 4500 | { |
| 4501 | case elfcpp::R_ARM_NONE: |
| 4502 | break; |
| 4503 | |
| 4504 | case elfcpp::R_ARM_ABS8: |
| 4505 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 4506 | output_section)) |
| 4507 | reloc_status = Arm_relocate_functions::abs8(view, object, psymval); |
| 4508 | break; |
| 4509 | |
| 4510 | case elfcpp::R_ARM_ABS12: |
| 4511 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 4512 | output_section)) |
| 4513 | reloc_status = Arm_relocate_functions::abs12(view, object, psymval); |
| 4514 | break; |
| 4515 | |
| 4516 | case elfcpp::R_ARM_ABS16: |
| 4517 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 4518 | output_section)) |
| 4519 | reloc_status = Arm_relocate_functions::abs16(view, object, psymval); |
| 4520 | break; |
| 4521 | |
| 4522 | case elfcpp::R_ARM_ABS32: |
| 4523 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 4524 | output_section)) |
| 4525 | reloc_status = Arm_relocate_functions::abs32(view, object, psymval, |
| 4526 | thumb_bit); |
| 4527 | break; |
| 4528 | |
| 4529 | case elfcpp::R_ARM_ABS32_NOI: |
| 4530 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 4531 | output_section)) |
| 4532 | // No thumb bit for this relocation: (S + A) |
| 4533 | reloc_status = Arm_relocate_functions::abs32(view, object, psymval, |
| 4534 | false); |
| 4535 | break; |
| 4536 | |
| 4537 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 4538 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 4539 | output_section)) |
| 4540 | reloc_status = Arm_relocate_functions::movw_abs_nc(view, object, |
| 4541 | psymval, |
| 4542 | thumb_bit); |
| 4543 | else |
| 4544 | gold_error(_("relocation R_ARM_MOVW_ABS_NC cannot be used when making" |
| 4545 | "a shared object; recompile with -fPIC")); |
| 4546 | break; |
| 4547 | |
| 4548 | case elfcpp::R_ARM_MOVT_ABS: |
| 4549 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 4550 | output_section)) |
| 4551 | reloc_status = Arm_relocate_functions::movt_abs(view, object, psymval); |
| 4552 | else |
| 4553 | gold_error(_("relocation R_ARM_MOVT_ABS cannot be used when making" |
| 4554 | "a shared object; recompile with -fPIC")); |
| 4555 | break; |
| 4556 | |
| 4557 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 4558 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 4559 | output_section)) |
| 4560 | reloc_status = Arm_relocate_functions::thm_movw_abs_nc(view, object, |
| 4561 | psymval, |
| 4562 | thumb_bit); |
| 4563 | else |
| 4564 | gold_error(_("relocation R_ARM_THM_MOVW_ABS_NC cannot be used when" |
| 4565 | "making a shared object; recompile with -fPIC")); |
| 4566 | break; |
| 4567 | |
| 4568 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 4569 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 4570 | output_section)) |
| 4571 | reloc_status = Arm_relocate_functions::thm_movt_abs(view, object, |
| 4572 | psymval); |
| 4573 | else |
| 4574 | gold_error(_("relocation R_ARM_THM_MOVT_ABS cannot be used when" |
| 4575 | "making a shared object; recompile with -fPIC")); |
| 4576 | break; |
| 4577 | |
| 4578 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 4579 | reloc_status = Arm_relocate_functions::movw_prel_nc(view, object, |
| 4580 | psymval, address, |
| 4581 | thumb_bit); |
| 4582 | break; |
| 4583 | |
| 4584 | case elfcpp::R_ARM_MOVT_PREL: |
| 4585 | reloc_status = Arm_relocate_functions::movt_prel(view, object, |
| 4586 | psymval, address); |
| 4587 | break; |
| 4588 | |
| 4589 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 4590 | reloc_status = Arm_relocate_functions::thm_movw_prel_nc(view, object, |
| 4591 | psymval, address, |
| 4592 | thumb_bit); |
| 4593 | break; |
| 4594 | |
| 4595 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 4596 | reloc_status = Arm_relocate_functions::thm_movt_prel(view, object, |
| 4597 | psymval, address); |
| 4598 | break; |
| 4599 | |
| 4600 | case elfcpp::R_ARM_REL32: |
| 4601 | reloc_status = Arm_relocate_functions::rel32(view, object, psymval, |
| 4602 | address, thumb_bit); |
| 4603 | break; |
| 4604 | |
| 4605 | case elfcpp::R_ARM_THM_ABS5: |
| 4606 | if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false, |
| 4607 | output_section)) |
| 4608 | reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval); |
| 4609 | break; |
| 4610 | |
| 4611 | case elfcpp::R_ARM_THM_CALL: |
| 4612 | reloc_status = Arm_relocate_functions::thm_call(view, object, psymval, |
| 4613 | address, thumb_bit); |
| 4614 | break; |
| 4615 | |
| 4616 | case elfcpp::R_ARM_GOTOFF32: |
| 4617 | { |
| 4618 | Arm_address got_origin; |
| 4619 | got_origin = target->got_plt_section()->address(); |
| 4620 | reloc_status = Arm_relocate_functions::rel32(view, object, psymval, |
| 4621 | got_origin, thumb_bit); |
| 4622 | } |
| 4623 | break; |
| 4624 | |
| 4625 | case elfcpp::R_ARM_BASE_PREL: |
| 4626 | { |
| 4627 | uint32_t origin; |
| 4628 | // Get the addressing origin of the output segment defining the |
| 4629 | // symbol gsym (AAELF 4.6.1.2 Relocation types) |
| 4630 | gold_assert(gsym != NULL); |
| 4631 | if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT) |
| 4632 | origin = gsym->output_segment()->vaddr(); |
| 4633 | else if (gsym->source () == Symbol::IN_OUTPUT_DATA) |
| 4634 | origin = gsym->output_data()->address(); |
| 4635 | else |
| 4636 | { |
| 4637 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 4638 | _("cannot find origin of R_ARM_BASE_PREL")); |
| 4639 | return true; |
| 4640 | } |
| 4641 | reloc_status = Arm_relocate_functions::base_prel(view, origin, address); |
| 4642 | } |
| 4643 | break; |
| 4644 | |
| 4645 | case elfcpp::R_ARM_BASE_ABS: |
| 4646 | { |
| 4647 | if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true, |
| 4648 | output_section)) |
| 4649 | break; |
| 4650 | |
| 4651 | uint32_t origin; |
| 4652 | // Get the addressing origin of the output segment defining |
| 4653 | // the symbol gsym (AAELF 4.6.1.2 Relocation types). |
| 4654 | if (gsym == NULL) |
| 4655 | // R_ARM_BASE_ABS with the NULL symbol will give the |
| 4656 | // absolute address of the GOT origin (GOT_ORG) (see ARM IHI |
| 4657 | // 0044C (AAELF): 4.6.1.8 Proxy generating relocations). |
| 4658 | origin = target->got_plt_section()->address(); |
| 4659 | else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT) |
| 4660 | origin = gsym->output_segment()->vaddr(); |
| 4661 | else if (gsym->source () == Symbol::IN_OUTPUT_DATA) |
| 4662 | origin = gsym->output_data()->address(); |
| 4663 | else |
| 4664 | { |
| 4665 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 4666 | _("cannot find origin of R_ARM_BASE_ABS")); |
| 4667 | return true; |
| 4668 | } |
| 4669 | |
| 4670 | reloc_status = Arm_relocate_functions::base_abs(view, origin); |
| 4671 | } |
| 4672 | break; |
| 4673 | |
| 4674 | case elfcpp::R_ARM_GOT_BREL: |
| 4675 | gold_assert(have_got_offset); |
| 4676 | reloc_status = Arm_relocate_functions::got_brel(view, got_offset); |
| 4677 | break; |
| 4678 | |
| 4679 | case elfcpp::R_ARM_GOT_PREL: |
| 4680 | gold_assert(have_got_offset); |
| 4681 | // Get the address origin for GOT PLT, which is allocated right |
| 4682 | // after the GOT section, to calculate an absolute address of |
| 4683 | // the symbol GOT entry (got_origin + got_offset). |
| 4684 | Arm_address got_origin; |
| 4685 | got_origin = target->got_plt_section()->address(); |
| 4686 | reloc_status = Arm_relocate_functions::got_prel(view, |
| 4687 | got_origin + got_offset, |
| 4688 | address); |
| 4689 | break; |
| 4690 | |
| 4691 | case elfcpp::R_ARM_PLT32: |
| 4692 | gold_assert(gsym == NULL |
| 4693 | || gsym->has_plt_offset() |
| 4694 | || gsym->final_value_is_known() |
| 4695 | || (gsym->is_defined() |
| 4696 | && !gsym->is_from_dynobj() |
| 4697 | && !gsym->is_preemptible())); |
| 4698 | reloc_status = Arm_relocate_functions::plt32(view, object, psymval, |
| 4699 | address, thumb_bit); |
| 4700 | break; |
| 4701 | |
| 4702 | case elfcpp::R_ARM_CALL: |
| 4703 | reloc_status = Arm_relocate_functions::call(view, object, psymval, |
| 4704 | address, thumb_bit); |
| 4705 | break; |
| 4706 | |
| 4707 | case elfcpp::R_ARM_JUMP24: |
| 4708 | reloc_status = Arm_relocate_functions::jump24(view, object, psymval, |
| 4709 | address, thumb_bit); |
| 4710 | break; |
| 4711 | |
| 4712 | case elfcpp::R_ARM_PREL31: |
| 4713 | reloc_status = Arm_relocate_functions::prel31(view, object, psymval, |
| 4714 | address, thumb_bit); |
| 4715 | break; |
| 4716 | |
| 4717 | case elfcpp::R_ARM_TARGET1: |
| 4718 | // This should have been mapped to another type already. |
| 4719 | // Fall through. |
| 4720 | case elfcpp::R_ARM_COPY: |
| 4721 | case elfcpp::R_ARM_GLOB_DAT: |
| 4722 | case elfcpp::R_ARM_JUMP_SLOT: |
| 4723 | case elfcpp::R_ARM_RELATIVE: |
| 4724 | // These are relocations which should only be seen by the |
| 4725 | // dynamic linker, and should never be seen here. |
| 4726 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 4727 | _("unexpected reloc %u in object file"), |
| 4728 | r_type); |
| 4729 | break; |
| 4730 | |
| 4731 | default: |
| 4732 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 4733 | _("unsupported reloc %u"), |
| 4734 | r_type); |
| 4735 | break; |
| 4736 | } |
| 4737 | |
| 4738 | // Report any errors. |
| 4739 | switch (reloc_status) |
| 4740 | { |
| 4741 | case Arm_relocate_functions::STATUS_OKAY: |
| 4742 | break; |
| 4743 | case Arm_relocate_functions::STATUS_OVERFLOW: |
| 4744 | gold_error_at_location(relinfo, relnum, rel.get_r_offset(), |
| 4745 | _("relocation overflow in relocation %u"), |
| 4746 | r_type); |
| 4747 | break; |
| 4748 | case Arm_relocate_functions::STATUS_BAD_RELOC: |
| 4749 | gold_error_at_location( |
| 4750 | relinfo, |
| 4751 | relnum, |
| 4752 | rel.get_r_offset(), |
| 4753 | _("unexpected opcode while processing relocation %u"), |
| 4754 | r_type); |
| 4755 | break; |
| 4756 | default: |
| 4757 | gold_unreachable(); |
| 4758 | } |
| 4759 | |
| 4760 | return true; |
| 4761 | } |
| 4762 | |
| 4763 | // Relocate section data. |
| 4764 | |
| 4765 | template<bool big_endian> |
| 4766 | void |
| 4767 | Target_arm<big_endian>::relocate_section( |
| 4768 | const Relocate_info<32, big_endian>* relinfo, |
| 4769 | unsigned int sh_type, |
| 4770 | const unsigned char* prelocs, |
| 4771 | size_t reloc_count, |
| 4772 | Output_section* output_section, |
| 4773 | bool needs_special_offset_handling, |
| 4774 | unsigned char* view, |
| 4775 | Arm_address address, |
| 4776 | section_size_type view_size, |
| 4777 | const Reloc_symbol_changes* reloc_symbol_changes) |
| 4778 | { |
| 4779 | typedef typename Target_arm<big_endian>::Relocate Arm_relocate; |
| 4780 | gold_assert(sh_type == elfcpp::SHT_REL); |
| 4781 | |
| 4782 | Arm_input_section<big_endian>* arm_input_section = |
| 4783 | this->find_arm_input_section(relinfo->object, relinfo->data_shndx); |
| 4784 | |
| 4785 | // This is an ARM input section and the view covers the whole output |
| 4786 | // section. |
| 4787 | if (arm_input_section != NULL) |
| 4788 | { |
| 4789 | gold_assert(needs_special_offset_handling); |
| 4790 | Arm_address section_address = arm_input_section->address(); |
| 4791 | section_size_type section_size = arm_input_section->data_size(); |
| 4792 | |
| 4793 | gold_assert((arm_input_section->address() >= address) |
| 4794 | && ((arm_input_section->address() |
| 4795 | + arm_input_section->data_size()) |
| 4796 | <= (address + view_size))); |
| 4797 | |
| 4798 | off_t offset = section_address - address; |
| 4799 | view += offset; |
| 4800 | address += offset; |
| 4801 | view_size = section_size; |
| 4802 | } |
| 4803 | |
| 4804 | gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL, |
| 4805 | Arm_relocate>( |
| 4806 | relinfo, |
| 4807 | this, |
| 4808 | prelocs, |
| 4809 | reloc_count, |
| 4810 | output_section, |
| 4811 | needs_special_offset_handling, |
| 4812 | view, |
| 4813 | address, |
| 4814 | view_size, |
| 4815 | reloc_symbol_changes); |
| 4816 | } |
| 4817 | |
| 4818 | // Return the size of a relocation while scanning during a relocatable |
| 4819 | // link. |
| 4820 | |
| 4821 | template<bool big_endian> |
| 4822 | unsigned int |
| 4823 | Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc( |
| 4824 | unsigned int r_type, |
| 4825 | Relobj* object) |
| 4826 | { |
| 4827 | r_type = get_real_reloc_type(r_type); |
| 4828 | switch (r_type) |
| 4829 | { |
| 4830 | case elfcpp::R_ARM_NONE: |
| 4831 | return 0; |
| 4832 | |
| 4833 | case elfcpp::R_ARM_ABS8: |
| 4834 | return 1; |
| 4835 | |
| 4836 | case elfcpp::R_ARM_ABS16: |
| 4837 | case elfcpp::R_ARM_THM_ABS5: |
| 4838 | return 2; |
| 4839 | |
| 4840 | case elfcpp::R_ARM_ABS32: |
| 4841 | case elfcpp::R_ARM_ABS32_NOI: |
| 4842 | case elfcpp::R_ARM_ABS12: |
| 4843 | case elfcpp::R_ARM_BASE_ABS: |
| 4844 | case elfcpp::R_ARM_REL32: |
| 4845 | case elfcpp::R_ARM_THM_CALL: |
| 4846 | case elfcpp::R_ARM_GOTOFF32: |
| 4847 | case elfcpp::R_ARM_BASE_PREL: |
| 4848 | case elfcpp::R_ARM_GOT_BREL: |
| 4849 | case elfcpp::R_ARM_GOT_PREL: |
| 4850 | case elfcpp::R_ARM_PLT32: |
| 4851 | case elfcpp::R_ARM_CALL: |
| 4852 | case elfcpp::R_ARM_JUMP24: |
| 4853 | case elfcpp::R_ARM_PREL31: |
| 4854 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 4855 | case elfcpp::R_ARM_MOVT_ABS: |
| 4856 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 4857 | case elfcpp::R_ARM_THM_MOVT_ABS: |
| 4858 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 4859 | case elfcpp::R_ARM_MOVT_PREL: |
| 4860 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 4861 | case elfcpp::R_ARM_THM_MOVT_PREL: |
| 4862 | return 4; |
| 4863 | |
| 4864 | case elfcpp::R_ARM_TARGET1: |
| 4865 | // This should have been mapped to another type already. |
| 4866 | // Fall through. |
| 4867 | case elfcpp::R_ARM_COPY: |
| 4868 | case elfcpp::R_ARM_GLOB_DAT: |
| 4869 | case elfcpp::R_ARM_JUMP_SLOT: |
| 4870 | case elfcpp::R_ARM_RELATIVE: |
| 4871 | // These are relocations which should only be seen by the |
| 4872 | // dynamic linker, and should never be seen here. |
| 4873 | gold_error(_("%s: unexpected reloc %u in object file"), |
| 4874 | object->name().c_str(), r_type); |
| 4875 | return 0; |
| 4876 | |
| 4877 | default: |
| 4878 | object->error(_("unsupported reloc %u in object file"), r_type); |
| 4879 | return 0; |
| 4880 | } |
| 4881 | } |
| 4882 | |
| 4883 | // Scan the relocs during a relocatable link. |
| 4884 | |
| 4885 | template<bool big_endian> |
| 4886 | void |
| 4887 | Target_arm<big_endian>::scan_relocatable_relocs( |
| 4888 | Symbol_table* symtab, |
| 4889 | Layout* layout, |
| 4890 | Sized_relobj<32, big_endian>* object, |
| 4891 | unsigned int data_shndx, |
| 4892 | unsigned int sh_type, |
| 4893 | const unsigned char* prelocs, |
| 4894 | size_t reloc_count, |
| 4895 | Output_section* output_section, |
| 4896 | bool needs_special_offset_handling, |
| 4897 | size_t local_symbol_count, |
| 4898 | const unsigned char* plocal_symbols, |
| 4899 | Relocatable_relocs* rr) |
| 4900 | { |
| 4901 | gold_assert(sh_type == elfcpp::SHT_REL); |
| 4902 | |
| 4903 | typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL, |
| 4904 | Relocatable_size_for_reloc> Scan_relocatable_relocs; |
| 4905 | |
| 4906 | gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL, |
| 4907 | Scan_relocatable_relocs>( |
| 4908 | symtab, |
| 4909 | layout, |
| 4910 | object, |
| 4911 | data_shndx, |
| 4912 | prelocs, |
| 4913 | reloc_count, |
| 4914 | output_section, |
| 4915 | needs_special_offset_handling, |
| 4916 | local_symbol_count, |
| 4917 | plocal_symbols, |
| 4918 | rr); |
| 4919 | } |
| 4920 | |
| 4921 | // Relocate a section during a relocatable link. |
| 4922 | |
| 4923 | template<bool big_endian> |
| 4924 | void |
| 4925 | Target_arm<big_endian>::relocate_for_relocatable( |
| 4926 | const Relocate_info<32, big_endian>* relinfo, |
| 4927 | unsigned int sh_type, |
| 4928 | const unsigned char* prelocs, |
| 4929 | size_t reloc_count, |
| 4930 | Output_section* output_section, |
| 4931 | off_t offset_in_output_section, |
| 4932 | const Relocatable_relocs* rr, |
| 4933 | unsigned char* view, |
| 4934 | Arm_address view_address, |
| 4935 | section_size_type view_size, |
| 4936 | unsigned char* reloc_view, |
| 4937 | section_size_type reloc_view_size) |
| 4938 | { |
| 4939 | gold_assert(sh_type == elfcpp::SHT_REL); |
| 4940 | |
| 4941 | gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>( |
| 4942 | relinfo, |
| 4943 | prelocs, |
| 4944 | reloc_count, |
| 4945 | output_section, |
| 4946 | offset_in_output_section, |
| 4947 | rr, |
| 4948 | view, |
| 4949 | view_address, |
| 4950 | view_size, |
| 4951 | reloc_view, |
| 4952 | reloc_view_size); |
| 4953 | } |
| 4954 | |
| 4955 | // Return the value to use for a dynamic symbol which requires special |
| 4956 | // treatment. This is how we support equality comparisons of function |
| 4957 | // pointers across shared library boundaries, as described in the |
| 4958 | // processor specific ABI supplement. |
| 4959 | |
| 4960 | template<bool big_endian> |
| 4961 | uint64_t |
| 4962 | Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const |
| 4963 | { |
| 4964 | gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset()); |
| 4965 | return this->plt_section()->address() + gsym->plt_offset(); |
| 4966 | } |
| 4967 | |
| 4968 | // Map platform-specific relocs to real relocs |
| 4969 | // |
| 4970 | template<bool big_endian> |
| 4971 | unsigned int |
| 4972 | Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type) |
| 4973 | { |
| 4974 | switch (r_type) |
| 4975 | { |
| 4976 | case elfcpp::R_ARM_TARGET1: |
| 4977 | // This is either R_ARM_ABS32 or R_ARM_REL32; |
| 4978 | return elfcpp::R_ARM_ABS32; |
| 4979 | |
| 4980 | case elfcpp::R_ARM_TARGET2: |
| 4981 | // This can be any reloc type but ususally is R_ARM_GOT_PREL |
| 4982 | return elfcpp::R_ARM_GOT_PREL; |
| 4983 | |
| 4984 | default: |
| 4985 | return r_type; |
| 4986 | } |
| 4987 | } |
| 4988 | |
| 4989 | // Whether if two EABI versions V1 and V2 are compatible. |
| 4990 | |
| 4991 | template<bool big_endian> |
| 4992 | bool |
| 4993 | Target_arm<big_endian>::are_eabi_versions_compatible( |
| 4994 | elfcpp::Elf_Word v1, |
| 4995 | elfcpp::Elf_Word v2) |
| 4996 | { |
| 4997 | // v4 and v5 are the same spec before and after it was released, |
| 4998 | // so allow mixing them. |
| 4999 | if ((v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5) |
| 5000 | || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4)) |
| 5001 | return true; |
| 5002 | |
| 5003 | return v1 == v2; |
| 5004 | } |
| 5005 | |
| 5006 | // Combine FLAGS from an input object called NAME and the processor-specific |
| 5007 | // flags in the ELF header of the output. Much of this is adapted from the |
| 5008 | // processor-specific flags merging code in elf32_arm_merge_private_bfd_data |
| 5009 | // in bfd/elf32-arm.c. |
| 5010 | |
| 5011 | template<bool big_endian> |
| 5012 | void |
| 5013 | Target_arm<big_endian>::merge_processor_specific_flags( |
| 5014 | const std::string& name, |
| 5015 | elfcpp::Elf_Word flags) |
| 5016 | { |
| 5017 | if (this->are_processor_specific_flags_set()) |
| 5018 | { |
| 5019 | elfcpp::Elf_Word out_flags = this->processor_specific_flags(); |
| 5020 | |
| 5021 | // Nothing to merge if flags equal to those in output. |
| 5022 | if (flags == out_flags) |
| 5023 | return; |
| 5024 | |
| 5025 | // Complain about various flag mismatches. |
| 5026 | elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags); |
| 5027 | elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags); |
| 5028 | if (!this->are_eabi_versions_compatible(version1, version2)) |
| 5029 | gold_error(_("Source object %s has EABI version %d but output has " |
| 5030 | "EABI version %d."), |
| 5031 | name.c_str(), |
| 5032 | (flags & elfcpp::EF_ARM_EABIMASK) >> 24, |
| 5033 | (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24); |
| 5034 | } |
| 5035 | else |
| 5036 | { |
| 5037 | // If the input is the default architecture and had the default |
| 5038 | // flags then do not bother setting the flags for the output |
| 5039 | // architecture, instead allow future merges to do this. If no |
| 5040 | // future merges ever set these flags then they will retain their |
| 5041 | // uninitialised values, which surprise surprise, correspond |
| 5042 | // to the default values. |
| 5043 | if (flags == 0) |
| 5044 | return; |
| 5045 | |
| 5046 | // This is the first time, just copy the flags. |
| 5047 | // We only copy the EABI version for now. |
| 5048 | this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK); |
| 5049 | } |
| 5050 | } |
| 5051 | |
| 5052 | // Adjust ELF file header. |
| 5053 | template<bool big_endian> |
| 5054 | void |
| 5055 | Target_arm<big_endian>::do_adjust_elf_header( |
| 5056 | unsigned char* view, |
| 5057 | int len) const |
| 5058 | { |
| 5059 | gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size); |
| 5060 | |
| 5061 | elfcpp::Ehdr<32, big_endian> ehdr(view); |
| 5062 | unsigned char e_ident[elfcpp::EI_NIDENT]; |
| 5063 | memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT); |
| 5064 | |
| 5065 | if (elfcpp::arm_eabi_version(this->processor_specific_flags()) |
| 5066 | == elfcpp::EF_ARM_EABI_UNKNOWN) |
| 5067 | e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM; |
| 5068 | else |
| 5069 | e_ident[elfcpp::EI_OSABI] = 0; |
| 5070 | e_ident[elfcpp::EI_ABIVERSION] = 0; |
| 5071 | |
| 5072 | // FIXME: Do EF_ARM_BE8 adjustment. |
| 5073 | |
| 5074 | elfcpp::Ehdr_write<32, big_endian> oehdr(view); |
| 5075 | oehdr.put_e_ident(e_ident); |
| 5076 | } |
| 5077 | |
| 5078 | // do_make_elf_object to override the same function in the base class. |
| 5079 | // We need to use a target-specific sub-class of Sized_relobj<32, big_endian> |
| 5080 | // to store ARM specific information. Hence we need to have our own |
| 5081 | // ELF object creation. |
| 5082 | |
| 5083 | template<bool big_endian> |
| 5084 | Object* |
| 5085 | Target_arm<big_endian>::do_make_elf_object( |
| 5086 | const std::string& name, |
| 5087 | Input_file* input_file, |
| 5088 | off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr) |
| 5089 | { |
| 5090 | int et = ehdr.get_e_type(); |
| 5091 | if (et == elfcpp::ET_REL) |
| 5092 | { |
| 5093 | Arm_relobj<big_endian>* obj = |
| 5094 | new Arm_relobj<big_endian>(name, input_file, offset, ehdr); |
| 5095 | obj->setup(); |
| 5096 | return obj; |
| 5097 | } |
| 5098 | else if (et == elfcpp::ET_DYN) |
| 5099 | { |
| 5100 | Sized_dynobj<32, big_endian>* obj = |
| 5101 | new Arm_dynobj<big_endian>(name, input_file, offset, ehdr); |
| 5102 | obj->setup(); |
| 5103 | return obj; |
| 5104 | } |
| 5105 | else |
| 5106 | { |
| 5107 | gold_error(_("%s: unsupported ELF file type %d"), |
| 5108 | name.c_str(), et); |
| 5109 | return NULL; |
| 5110 | } |
| 5111 | } |
| 5112 | |
| 5113 | // Return whether a relocation type used the LSB to distinguish THUMB |
| 5114 | // addresses. |
| 5115 | template<bool big_endian> |
| 5116 | bool |
| 5117 | Target_arm<big_endian>::reloc_uses_thumb_bit(unsigned int r_type) |
| 5118 | { |
| 5119 | switch (r_type) |
| 5120 | { |
| 5121 | case elfcpp::R_ARM_PC24: |
| 5122 | case elfcpp::R_ARM_ABS32: |
| 5123 | case elfcpp::R_ARM_REL32: |
| 5124 | case elfcpp::R_ARM_SBREL32: |
| 5125 | case elfcpp::R_ARM_THM_CALL: |
| 5126 | case elfcpp::R_ARM_GLOB_DAT: |
| 5127 | case elfcpp::R_ARM_JUMP_SLOT: |
| 5128 | case elfcpp::R_ARM_GOTOFF32: |
| 5129 | case elfcpp::R_ARM_PLT32: |
| 5130 | case elfcpp::R_ARM_CALL: |
| 5131 | case elfcpp::R_ARM_JUMP24: |
| 5132 | case elfcpp::R_ARM_THM_JUMP24: |
| 5133 | case elfcpp::R_ARM_SBREL31: |
| 5134 | case elfcpp::R_ARM_PREL31: |
| 5135 | case elfcpp::R_ARM_MOVW_ABS_NC: |
| 5136 | case elfcpp::R_ARM_MOVW_PREL_NC: |
| 5137 | case elfcpp::R_ARM_THM_MOVW_ABS_NC: |
| 5138 | case elfcpp::R_ARM_THM_MOVW_PREL_NC: |
| 5139 | case elfcpp::R_ARM_THM_JUMP19: |
| 5140 | case elfcpp::R_ARM_THM_ALU_PREL_11_0: |
| 5141 | case elfcpp::R_ARM_ALU_PC_G0_NC: |
| 5142 | case elfcpp::R_ARM_ALU_PC_G0: |
| 5143 | case elfcpp::R_ARM_ALU_PC_G1_NC: |
| 5144 | case elfcpp::R_ARM_ALU_PC_G1: |
| 5145 | case elfcpp::R_ARM_ALU_PC_G2: |
| 5146 | case elfcpp::R_ARM_ALU_SB_G0_NC: |
| 5147 | case elfcpp::R_ARM_ALU_SB_G0: |
| 5148 | case elfcpp::R_ARM_ALU_SB_G1_NC: |
| 5149 | case elfcpp::R_ARM_ALU_SB_G1: |
| 5150 | case elfcpp::R_ARM_ALU_SB_G2: |
| 5151 | case elfcpp::R_ARM_MOVW_BREL_NC: |
| 5152 | case elfcpp::R_ARM_MOVW_BREL: |
| 5153 | case elfcpp::R_ARM_THM_MOVW_BREL_NC: |
| 5154 | case elfcpp::R_ARM_THM_MOVW_BREL: |
| 5155 | return true; |
| 5156 | default: |
| 5157 | return false; |
| 5158 | } |
| 5159 | } |
| 5160 | |
| 5161 | // Stub-generation methods for Target_arm. |
| 5162 | |
| 5163 | // Make a new Arm_input_section object. |
| 5164 | |
| 5165 | template<bool big_endian> |
| 5166 | Arm_input_section<big_endian>* |
| 5167 | Target_arm<big_endian>::new_arm_input_section( |
| 5168 | Relobj* relobj, |
| 5169 | unsigned int shndx) |
| 5170 | { |
| 5171 | Input_section_specifier iss(relobj, shndx); |
| 5172 | |
| 5173 | Arm_input_section<big_endian>* arm_input_section = |
| 5174 | new Arm_input_section<big_endian>(relobj, shndx); |
| 5175 | arm_input_section->init(); |
| 5176 | |
| 5177 | // Register new Arm_input_section in map for look-up. |
| 5178 | std::pair<typename Arm_input_section_map::iterator, bool> ins = |
| 5179 | this->arm_input_section_map_.insert(std::make_pair(iss, arm_input_section)); |
| 5180 | |
| 5181 | // Make sure that it we have not created another Arm_input_section |
| 5182 | // for this input section already. |
| 5183 | gold_assert(ins.second); |
| 5184 | |
| 5185 | return arm_input_section; |
| 5186 | } |
| 5187 | |
| 5188 | // Find the Arm_input_section object corresponding to the SHNDX-th input |
| 5189 | // section of RELOBJ. |
| 5190 | |
| 5191 | template<bool big_endian> |
| 5192 | Arm_input_section<big_endian>* |
| 5193 | Target_arm<big_endian>::find_arm_input_section( |
| 5194 | Relobj* relobj, |
| 5195 | unsigned int shndx) const |
| 5196 | { |
| 5197 | Input_section_specifier iss(relobj, shndx); |
| 5198 | typename Arm_input_section_map::const_iterator p = |
| 5199 | this->arm_input_section_map_.find(iss); |
| 5200 | return (p != this->arm_input_section_map_.end()) ? p->second : NULL; |
| 5201 | } |
| 5202 | |
| 5203 | // Make a new stub table. |
| 5204 | |
| 5205 | template<bool big_endian> |
| 5206 | Stub_table<big_endian>* |
| 5207 | Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner) |
| 5208 | { |
| 5209 | Stub_table<big_endian>* stub_table = |
| 5210 | new Stub_table<big_endian>(owner); |
| 5211 | this->stub_tables_.push_back(stub_table); |
| 5212 | |
| 5213 | stub_table->set_address(owner->address() + owner->data_size()); |
| 5214 | stub_table->set_file_offset(owner->offset() + owner->data_size()); |
| 5215 | stub_table->finalize_data_size(); |
| 5216 | |
| 5217 | return stub_table; |
| 5218 | } |
| 5219 | |
| 5220 | // Scan a relocation for stub generation. |
| 5221 | |
| 5222 | template<bool big_endian> |
| 5223 | void |
| 5224 | Target_arm<big_endian>::scan_reloc_for_stub( |
| 5225 | const Relocate_info<32, big_endian>* relinfo, |
| 5226 | unsigned int r_type, |
| 5227 | const Sized_symbol<32>* gsym, |
| 5228 | unsigned int r_sym, |
| 5229 | const Symbol_value<32>* psymval, |
| 5230 | elfcpp::Elf_types<32>::Elf_Swxword addend, |
| 5231 | Arm_address address) |
| 5232 | { |
| 5233 | typedef typename Target_arm<big_endian>::Relocate Relocate; |
| 5234 | |
| 5235 | const Arm_relobj<big_endian>* arm_relobj = |
| 5236 | Arm_relobj<big_endian>::as_arm_relobj(relinfo->object); |
| 5237 | |
| 5238 | bool target_is_thumb; |
| 5239 | Symbol_value<32> symval; |
| 5240 | if (gsym != NULL) |
| 5241 | { |
| 5242 | // This is a global symbol. Determine if we use PLT and if the |
| 5243 | // final target is THUMB. |
| 5244 | if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type))) |
| 5245 | { |
| 5246 | // This uses a PLT, change the symbol value. |
| 5247 | symval.set_output_value(this->plt_section()->address() |
| 5248 | + gsym->plt_offset()); |
| 5249 | psymval = &symval; |
| 5250 | target_is_thumb = false; |
| 5251 | } |
| 5252 | else if (gsym->is_undefined()) |
| 5253 | // There is no need to generate a stub symbol is undefined. |
| 5254 | return; |
| 5255 | else |
| 5256 | { |
| 5257 | target_is_thumb = |
| 5258 | ((gsym->type() == elfcpp::STT_ARM_TFUNC) |
| 5259 | || (gsym->type() == elfcpp::STT_FUNC |
| 5260 | && !gsym->is_undefined() |
| 5261 | && ((psymval->value(arm_relobj, 0) & 1) != 0))); |
| 5262 | } |
| 5263 | } |
| 5264 | else |
| 5265 | { |
| 5266 | // This is a local symbol. Determine if the final target is THUMB. |
| 5267 | target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym); |
| 5268 | } |
| 5269 | |
| 5270 | // Strip LSB if this points to a THUMB target. |
| 5271 | if (target_is_thumb |
| 5272 | && Target_arm<big_endian>::reloc_uses_thumb_bit(r_type) |
| 5273 | && ((psymval->value(arm_relobj, 0) & 1) != 0)) |
| 5274 | { |
| 5275 | Arm_address stripped_value = |
| 5276 | psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1); |
| 5277 | symval.set_output_value(stripped_value); |
| 5278 | psymval = &symval; |
| 5279 | } |
| 5280 | |
| 5281 | // Get the symbol value. |
| 5282 | Symbol_value<32>::Value value = psymval->value(arm_relobj, 0); |
| 5283 | |
| 5284 | // Owing to pipelining, the PC relative branches below actually skip |
| 5285 | // two instructions when the branch offset is 0. |
| 5286 | Arm_address destination; |
| 5287 | switch (r_type) |
| 5288 | { |
| 5289 | case elfcpp::R_ARM_CALL: |
| 5290 | case elfcpp::R_ARM_JUMP24: |
| 5291 | case elfcpp::R_ARM_PLT32: |
| 5292 | // ARM branches. |
| 5293 | destination = value + addend + 8; |
| 5294 | break; |
| 5295 | case elfcpp::R_ARM_THM_CALL: |
| 5296 | case elfcpp::R_ARM_THM_XPC22: |
| 5297 | case elfcpp::R_ARM_THM_JUMP24: |
| 5298 | case elfcpp::R_ARM_THM_JUMP19: |
| 5299 | // THUMB branches. |
| 5300 | destination = value + addend + 4; |
| 5301 | break; |
| 5302 | default: |
| 5303 | gold_unreachable(); |
| 5304 | } |
| 5305 | |
| 5306 | Stub_type stub_type = |
| 5307 | Reloc_stub::stub_type_for_reloc(r_type, address, destination, |
| 5308 | target_is_thumb); |
| 5309 | |
| 5310 | // This reloc does not need a stub. |
| 5311 | if (stub_type == arm_stub_none) |
| 5312 | return; |
| 5313 | |
| 5314 | // Try looking up an existing stub from a stub table. |
| 5315 | Stub_table<big_endian>* stub_table = |
| 5316 | arm_relobj->stub_table(relinfo->data_shndx); |
| 5317 | gold_assert(stub_table != NULL); |
| 5318 | |
| 5319 | // Locate stub by destination. |
| 5320 | Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend); |
| 5321 | |
| 5322 | // Create a stub if there is not one already |
| 5323 | Reloc_stub* stub = stub_table->find_reloc_stub(stub_key); |
| 5324 | if (stub == NULL) |
| 5325 | { |
| 5326 | // create a new stub and add it to stub table. |
| 5327 | stub = this->stub_factory().make_reloc_stub(stub_type); |
| 5328 | stub_table->add_reloc_stub(stub, stub_key); |
| 5329 | } |
| 5330 | |
| 5331 | // Record the destination address. |
| 5332 | stub->set_destination_address(destination |
| 5333 | | (target_is_thumb ? 1 : 0)); |
| 5334 | } |
| 5335 | |
| 5336 | // This function scans a relocation sections for stub generation. |
| 5337 | // The template parameter Relocate must be a class type which provides |
| 5338 | // a single function, relocate(), which implements the machine |
| 5339 | // specific part of a relocation. |
| 5340 | |
| 5341 | // BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type: |
| 5342 | // SHT_REL or SHT_RELA. |
| 5343 | |
| 5344 | // PRELOCS points to the relocation data. RELOC_COUNT is the number |
| 5345 | // of relocs. OUTPUT_SECTION is the output section. |
| 5346 | // NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be |
| 5347 | // mapped to output offsets. |
| 5348 | |
| 5349 | // VIEW is the section data, VIEW_ADDRESS is its memory address, and |
| 5350 | // VIEW_SIZE is the size. These refer to the input section, unless |
| 5351 | // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to |
| 5352 | // the output section. |
| 5353 | |
| 5354 | template<bool big_endian> |
| 5355 | template<int sh_type> |
| 5356 | void inline |
| 5357 | Target_arm<big_endian>::scan_reloc_section_for_stubs( |
| 5358 | const Relocate_info<32, big_endian>* relinfo, |
| 5359 | const unsigned char* prelocs, |
| 5360 | size_t reloc_count, |
| 5361 | Output_section* output_section, |
| 5362 | bool needs_special_offset_handling, |
| 5363 | const unsigned char* view, |
| 5364 | elfcpp::Elf_types<32>::Elf_Addr view_address, |
| 5365 | section_size_type) |
| 5366 | { |
| 5367 | typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype; |
| 5368 | const int reloc_size = |
| 5369 | Reloc_types<sh_type, 32, big_endian>::reloc_size; |
| 5370 | |
| 5371 | Arm_relobj<big_endian>* arm_object = |
| 5372 | Arm_relobj<big_endian>::as_arm_relobj(relinfo->object); |
| 5373 | unsigned int local_count = arm_object->local_symbol_count(); |
| 5374 | |
| 5375 | Comdat_behavior comdat_behavior = CB_UNDETERMINED; |
| 5376 | |
| 5377 | for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size) |
| 5378 | { |
| 5379 | Reltype reloc(prelocs); |
| 5380 | |
| 5381 | typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info(); |
| 5382 | unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info); |
| 5383 | unsigned int r_type = elfcpp::elf_r_type<32>(r_info); |
| 5384 | |
| 5385 | r_type = this->get_real_reloc_type(r_type); |
| 5386 | |
| 5387 | // Only a few relocation types need stubs. |
| 5388 | if ((r_type != elfcpp::R_ARM_CALL) |
| 5389 | && (r_type != elfcpp::R_ARM_JUMP24) |
| 5390 | && (r_type != elfcpp::R_ARM_PLT32) |
| 5391 | && (r_type != elfcpp::R_ARM_THM_CALL) |
| 5392 | && (r_type != elfcpp::R_ARM_THM_XPC22) |
| 5393 | && (r_type != elfcpp::R_ARM_THM_JUMP24) |
| 5394 | && (r_type != elfcpp::R_ARM_THM_JUMP19)) |
| 5395 | continue; |
| 5396 | |
| 5397 | section_offset_type offset = |
| 5398 | convert_to_section_size_type(reloc.get_r_offset()); |
| 5399 | |
| 5400 | if (needs_special_offset_handling) |
| 5401 | { |
| 5402 | offset = output_section->output_offset(relinfo->object, |
| 5403 | relinfo->data_shndx, |
| 5404 | offset); |
| 5405 | if (offset == -1) |
| 5406 | continue; |
| 5407 | } |
| 5408 | |
| 5409 | // Get the addend. |
| 5410 | Stub_addend_reader<sh_type, big_endian> stub_addend_reader; |
| 5411 | elfcpp::Elf_types<32>::Elf_Swxword addend = |
| 5412 | stub_addend_reader(r_type, view + offset, reloc); |
| 5413 | |
| 5414 | const Sized_symbol<32>* sym; |
| 5415 | |
| 5416 | Symbol_value<32> symval; |
| 5417 | const Symbol_value<32> *psymval; |
| 5418 | if (r_sym < local_count) |
| 5419 | { |
| 5420 | sym = NULL; |
| 5421 | psymval = arm_object->local_symbol(r_sym); |
| 5422 | |
| 5423 | // If the local symbol belongs to a section we are discarding, |
| 5424 | // and that section is a debug section, try to find the |
| 5425 | // corresponding kept section and map this symbol to its |
| 5426 | // counterpart in the kept section. The symbol must not |
| 5427 | // correspond to a section we are folding. |
| 5428 | bool is_ordinary; |
| 5429 | unsigned int shndx = psymval->input_shndx(&is_ordinary); |
| 5430 | if (is_ordinary |
| 5431 | && shndx != elfcpp::SHN_UNDEF |
| 5432 | && !arm_object->is_section_included(shndx) |
| 5433 | && !(relinfo->symtab->is_section_folded(arm_object, shndx))) |
| 5434 | { |
| 5435 | if (comdat_behavior == CB_UNDETERMINED) |
| 5436 | { |
| 5437 | std::string name = |
| 5438 | arm_object->section_name(relinfo->data_shndx); |
| 5439 | comdat_behavior = get_comdat_behavior(name.c_str()); |
| 5440 | } |
| 5441 | if (comdat_behavior == CB_PRETEND) |
| 5442 | { |
| 5443 | bool found; |
| 5444 | typename elfcpp::Elf_types<32>::Elf_Addr value = |
| 5445 | arm_object->map_to_kept_section(shndx, &found); |
| 5446 | if (found) |
| 5447 | symval.set_output_value(value + psymval->input_value()); |
| 5448 | else |
| 5449 | symval.set_output_value(0); |
| 5450 | } |
| 5451 | else |
| 5452 | { |
| 5453 | symval.set_output_value(0); |
| 5454 | } |
| 5455 | symval.set_no_output_symtab_entry(); |
| 5456 | psymval = &symval; |
| 5457 | } |
| 5458 | } |
| 5459 | else |
| 5460 | { |
| 5461 | const Symbol* gsym = arm_object->global_symbol(r_sym); |
| 5462 | gold_assert(gsym != NULL); |
| 5463 | if (gsym->is_forwarder()) |
| 5464 | gsym = relinfo->symtab->resolve_forwards(gsym); |
| 5465 | |
| 5466 | sym = static_cast<const Sized_symbol<32>*>(gsym); |
| 5467 | if (sym->has_symtab_index()) |
| 5468 | symval.set_output_symtab_index(sym->symtab_index()); |
| 5469 | else |
| 5470 | symval.set_no_output_symtab_entry(); |
| 5471 | |
| 5472 | // We need to compute the would-be final value of this global |
| 5473 | // symbol. |
| 5474 | const Symbol_table* symtab = relinfo->symtab; |
| 5475 | const Sized_symbol<32>* sized_symbol = |
| 5476 | symtab->get_sized_symbol<32>(gsym); |
| 5477 | Symbol_table::Compute_final_value_status status; |
| 5478 | Arm_address value = |
| 5479 | symtab->compute_final_value<32>(sized_symbol, &status); |
| 5480 | |
| 5481 | // Skip this if the symbol has not output section. |
| 5482 | if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION) |
| 5483 | continue; |
| 5484 | |
| 5485 | symval.set_output_value(value); |
| 5486 | psymval = &symval; |
| 5487 | } |
| 5488 | |
| 5489 | // If symbol is a section symbol, we don't know the actual type of |
| 5490 | // destination. Give up. |
| 5491 | if (psymval->is_section_symbol()) |
| 5492 | continue; |
| 5493 | |
| 5494 | this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval, |
| 5495 | addend, view_address + offset); |
| 5496 | } |
| 5497 | } |
| 5498 | |
| 5499 | // Scan an input section for stub generation. |
| 5500 | |
| 5501 | template<bool big_endian> |
| 5502 | void |
| 5503 | Target_arm<big_endian>::scan_section_for_stubs( |
| 5504 | const Relocate_info<32, big_endian>* relinfo, |
| 5505 | unsigned int sh_type, |
| 5506 | const unsigned char* prelocs, |
| 5507 | size_t reloc_count, |
| 5508 | Output_section* output_section, |
| 5509 | bool needs_special_offset_handling, |
| 5510 | const unsigned char* view, |
| 5511 | Arm_address view_address, |
| 5512 | section_size_type view_size) |
| 5513 | { |
| 5514 | if (sh_type == elfcpp::SHT_REL) |
| 5515 | this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>( |
| 5516 | relinfo, |
| 5517 | prelocs, |
| 5518 | reloc_count, |
| 5519 | output_section, |
| 5520 | needs_special_offset_handling, |
| 5521 | view, |
| 5522 | view_address, |
| 5523 | view_size); |
| 5524 | else if (sh_type == elfcpp::SHT_RELA) |
| 5525 | // We do not support RELA type relocations yet. This is provided for |
| 5526 | // completeness. |
| 5527 | this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>( |
| 5528 | relinfo, |
| 5529 | prelocs, |
| 5530 | reloc_count, |
| 5531 | output_section, |
| 5532 | needs_special_offset_handling, |
| 5533 | view, |
| 5534 | view_address, |
| 5535 | view_size); |
| 5536 | else |
| 5537 | gold_unreachable(); |
| 5538 | } |
| 5539 | |
| 5540 | // Group input sections for stub generation. |
| 5541 | // |
| 5542 | // We goup input sections in an output sections so that the total size, |
| 5543 | // including any padding space due to alignment is smaller than GROUP_SIZE |
| 5544 | // unless the only input section in group is bigger than GROUP_SIZE already. |
| 5545 | // Then an ARM stub table is created to follow the last input section |
| 5546 | // in group. For each group an ARM stub table is created an is placed |
| 5547 | // after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further |
| 5548 | // extend the group after the stub table. |
| 5549 | |
| 5550 | template<bool big_endian> |
| 5551 | void |
| 5552 | Target_arm<big_endian>::group_sections( |
| 5553 | Layout* layout, |
| 5554 | section_size_type group_size, |
| 5555 | bool stubs_always_after_branch) |
| 5556 | { |
| 5557 | // Group input sections and insert stub table |
| 5558 | Layout::Section_list section_list; |
| 5559 | layout->get_allocated_sections(§ion_list); |
| 5560 | for (Layout::Section_list::const_iterator p = section_list.begin(); |
| 5561 | p != section_list.end(); |
| 5562 | ++p) |
| 5563 | { |
| 5564 | Arm_output_section<big_endian>* output_section = |
| 5565 | Arm_output_section<big_endian>::as_arm_output_section(*p); |
| 5566 | output_section->group_sections(group_size, stubs_always_after_branch, |
| 5567 | this); |
| 5568 | } |
| 5569 | } |
| 5570 | |
| 5571 | // Relaxation hook. This is where we do stub generation. |
| 5572 | |
| 5573 | template<bool big_endian> |
| 5574 | bool |
| 5575 | Target_arm<big_endian>::do_relax( |
| 5576 | int pass, |
| 5577 | const Input_objects* input_objects, |
| 5578 | Symbol_table* symtab, |
| 5579 | Layout* layout) |
| 5580 | { |
| 5581 | // No need to generate stubs if this is a relocatable link. |
| 5582 | gold_assert(!parameters->options().relocatable()); |
| 5583 | |
| 5584 | // If this is the first pass, we need to group input sections into |
| 5585 | // stub groups. |
| 5586 | if (pass == 1) |
| 5587 | { |
| 5588 | // Determine the stub group size. The group size is the absolute |
| 5589 | // value of the parameter --stub-group-size. If --stub-group-size |
| 5590 | // is passed a negative value, we restict stubs to be always after |
| 5591 | // the stubbed branches. |
| 5592 | int32_t stub_group_size_param = |
| 5593 | parameters->options().stub_group_size(); |
| 5594 | bool stubs_always_after_branch = stub_group_size_param < 0; |
| 5595 | section_size_type stub_group_size = abs(stub_group_size_param); |
| 5596 | |
| 5597 | if (stub_group_size == 1) |
| 5598 | { |
| 5599 | // Default value. |
| 5600 | // Thumb branch range is +-4MB has to be used as the default |
| 5601 | // maximum size (a given section can contain both ARM and Thumb |
| 5602 | // code, so the worst case has to be taken into account). |
| 5603 | // |
| 5604 | // This value is 24K less than that, which allows for 2025 |
| 5605 | // 12-byte stubs. If we exceed that, then we will fail to link. |
| 5606 | // The user will have to relink with an explicit group size |
| 5607 | // option. |
| 5608 | stub_group_size = 4170000; |
| 5609 | } |
| 5610 | |
| 5611 | group_sections(layout, stub_group_size, stubs_always_after_branch); |
| 5612 | } |
| 5613 | |
| 5614 | // clear changed flags for all stub_tables |
| 5615 | typedef typename Stub_table_list::iterator Stub_table_iterator; |
| 5616 | for (Stub_table_iterator sp = this->stub_tables_.begin(); |
| 5617 | sp != this->stub_tables_.end(); |
| 5618 | ++sp) |
| 5619 | (*sp)->set_has_been_changed(false); |
| 5620 | |
| 5621 | // scan relocs for stubs |
| 5622 | for (Input_objects::Relobj_iterator op = input_objects->relobj_begin(); |
| 5623 | op != input_objects->relobj_end(); |
| 5624 | ++op) |
| 5625 | { |
| 5626 | Arm_relobj<big_endian>* arm_relobj = |
| 5627 | Arm_relobj<big_endian>::as_arm_relobj(*op); |
| 5628 | arm_relobj->scan_sections_for_stubs(this, symtab, layout); |
| 5629 | } |
| 5630 | |
| 5631 | bool any_stub_table_changed = false; |
| 5632 | for (Stub_table_iterator sp = this->stub_tables_.begin(); |
| 5633 | (sp != this->stub_tables_.end()) && !any_stub_table_changed; |
| 5634 | ++sp) |
| 5635 | { |
| 5636 | if ((*sp)->has_been_changed()) |
| 5637 | any_stub_table_changed = true; |
| 5638 | } |
| 5639 | |
| 5640 | return any_stub_table_changed; |
| 5641 | } |
| 5642 | |
| 5643 | // Relocate a stub. |
| 5644 | |
| 5645 | template<bool big_endian> |
| 5646 | void |
| 5647 | Target_arm<big_endian>::relocate_stub( |
| 5648 | Reloc_stub* stub, |
| 5649 | const Relocate_info<32, big_endian>* relinfo, |
| 5650 | Output_section* output_section, |
| 5651 | unsigned char* view, |
| 5652 | Arm_address address, |
| 5653 | section_size_type view_size) |
| 5654 | { |
| 5655 | Relocate relocate; |
| 5656 | const Stub_template* stub_template = stub->stub_template(); |
| 5657 | for (size_t i = 0; i < stub_template->reloc_count(); i++) |
| 5658 | { |
| 5659 | size_t reloc_insn_index = stub_template->reloc_insn_index(i); |
| 5660 | const Insn_template* insn = &stub_template->insns()[reloc_insn_index]; |
| 5661 | |
| 5662 | unsigned int r_type = insn->r_type(); |
| 5663 | section_size_type reloc_offset = stub_template->reloc_offset(i); |
| 5664 | section_size_type reloc_size = insn->size(); |
| 5665 | gold_assert(reloc_offset + reloc_size <= view_size); |
| 5666 | |
| 5667 | // This is the address of the stub destination. |
| 5668 | Arm_address target = stub->reloc_target(i); |
| 5669 | Symbol_value<32> symval; |
| 5670 | symval.set_output_value(target); |
| 5671 | |
| 5672 | // Synthesize a fake reloc just in case. We don't have a symbol so |
| 5673 | // we use 0. |
| 5674 | unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size]; |
| 5675 | memset(reloc_buffer, 0, sizeof(reloc_buffer)); |
| 5676 | elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer); |
| 5677 | reloc_write.put_r_offset(reloc_offset); |
| 5678 | reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type)); |
| 5679 | elfcpp::Rel<32, big_endian> rel(reloc_buffer); |
| 5680 | |
| 5681 | relocate.relocate(relinfo, this, output_section, |
| 5682 | this->fake_relnum_for_stubs, rel, r_type, |
| 5683 | NULL, &symval, view + reloc_offset, |
| 5684 | address + reloc_offset, reloc_size); |
| 5685 | } |
| 5686 | } |
| 5687 | |
| 5688 | // The selector for arm object files. |
| 5689 | |
| 5690 | template<bool big_endian> |
| 5691 | class Target_selector_arm : public Target_selector |
| 5692 | { |
| 5693 | public: |
| 5694 | Target_selector_arm() |
| 5695 | : Target_selector(elfcpp::EM_ARM, 32, big_endian, |
| 5696 | (big_endian ? "elf32-bigarm" : "elf32-littlearm")) |
| 5697 | { } |
| 5698 | |
| 5699 | Target* |
| 5700 | do_instantiate_target() |
| 5701 | { return new Target_arm<big_endian>(); } |
| 5702 | }; |
| 5703 | |
| 5704 | Target_selector_arm<false> target_selector_arm; |
| 5705 | Target_selector_arm<true> target_selector_armbe; |
| 5706 | |
| 5707 | } // End anonymous namespace. |