1 /* yyscript.y -- linker script grammar for gold. */ 2 3 /* Copyright (C) 2006-2016 Free Software Foundation, Inc. 4 Written by Ian Lance Taylor <iant (at) google.com>. 5 6 This file is part of gold. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 MA 02110-1301, USA. */ 22 23 /* This is a bison grammar to parse a subset of the original GNU ld 24 linker script language. */ 25 26 %{ 27 28 #include "config.h" 29 30 #include <stddef.h> 31 #include <stdint.h> 32 #include <stdlib.h> 33 #include <string.h> 34 35 #include "script-c.h" 36 37 %} 38 39 /* We need to use a pure parser because we might be multi-threaded. 40 We pass some arguments through the parser to the lexer. */ 41 42 %pure-parser 43 44 %parse-param {void* closure} 45 %lex-param {void* closure} 46 47 /* Since we require bison anyhow, we take advantage of it. */ 48 49 %error-verbose 50 51 /* The values associated with tokens. */ 52 53 %union { 54 /* A string. */ 55 struct Parser_string string; 56 /* A number. */ 57 uint64_t integer; 58 /* An expression. */ 59 Expression_ptr expr; 60 /* An output section header. */ 61 struct Parser_output_section_header output_section_header; 62 /* An output section trailer. */ 63 struct Parser_output_section_trailer output_section_trailer; 64 /* A section constraint. */ 65 enum Section_constraint constraint; 66 /* A complete input section specification. */ 67 struct Input_section_spec input_section_spec; 68 /* A list of wildcard specifications, with exclusions. */ 69 struct Wildcard_sections wildcard_sections; 70 /* A single wildcard specification. */ 71 struct Wildcard_section wildcard_section; 72 /* A list of strings. */ 73 String_list_ptr string_list; 74 /* Information for a program header. */ 75 struct Phdr_info phdr_info; 76 /* Used for version scripts and within VERSION {}. */ 77 struct Version_dependency_list* deplist; 78 struct Version_expression_list* versyms; 79 struct Version_tree* versnode; 80 enum Script_section_type section_type; 81 } 82 83 /* Operators, including a precedence table for expressions. */ 84 85 %right PLUSEQ MINUSEQ MULTEQ DIVEQ '=' LSHIFTEQ RSHIFTEQ ANDEQ OREQ 86 %right '?' ':' 87 %left OROR 88 %left ANDAND 89 %left '|' 90 %left '^' 91 %left '&' 92 %left EQ NE 93 %left '<' '>' LE GE 94 %left LSHIFT RSHIFT 95 %left '+' '-' 96 %left '*' '/' '%' 97 98 /* A fake operator used to indicate unary operator precedence. */ 99 %right UNARY 100 101 /* Constants. */ 102 103 %token <string> STRING 104 %token <string> QUOTED_STRING 105 %token <integer> INTEGER 106 107 /* Keywords. This list is taken from ldgram.y and ldlex.l in the old 108 GNU linker, with the keywords which only appear in MRI mode 109 removed. Not all these keywords are actually used in this grammar. 110 In most cases the keyword is recognized as the token name in upper 111 case. The comments indicate where this is not the case. */ 112 113 %token ABSOLUTE 114 %token ADDR 115 %token ALIGN_K /* ALIGN */ 116 %token ALIGNOF 117 %token ASSERT_K /* ASSERT */ 118 %token AS_NEEDED 119 %token AT 120 %token BIND 121 %token BLOCK 122 %token BYTE 123 %token CONSTANT 124 %token CONSTRUCTORS 125 %token COPY 126 %token CREATE_OBJECT_SYMBOLS 127 %token DATA_SEGMENT_ALIGN 128 %token DATA_SEGMENT_END 129 %token DATA_SEGMENT_RELRO_END 130 %token DEFINED 131 %token DSECT 132 %token ENTRY 133 %token EXCLUDE_FILE 134 %token EXTERN 135 %token FILL 136 %token FLOAT 137 %token FORCE_COMMON_ALLOCATION 138 %token GLOBAL /* global */ 139 %token GROUP 140 %token HIDDEN 141 %token HLL 142 %token INCLUDE 143 %token INHIBIT_COMMON_ALLOCATION 144 %token INFO 145 %token INPUT 146 %token KEEP 147 %token LEN 148 %token LENGTH /* LENGTH, l, len */ 149 %token LOADADDR 150 %token LOCAL /* local */ 151 %token LONG 152 %token MAP 153 %token MAX_K /* MAX */ 154 %token MEMORY 155 %token MIN_K /* MIN */ 156 %token NEXT 157 %token NOCROSSREFS 158 %token NOFLOAT 159 %token NOLOAD 160 %token ONLY_IF_RO 161 %token ONLY_IF_RW 162 %token ORG 163 %token ORIGIN /* ORIGIN, o, org */ 164 %token OUTPUT 165 %token OUTPUT_ARCH 166 %token OUTPUT_FORMAT 167 %token OVERLAY 168 %token PHDRS 169 %token PROVIDE 170 %token PROVIDE_HIDDEN 171 %token QUAD 172 %token SEARCH_DIR 173 %token SECTIONS 174 %token SEGMENT_START 175 %token SHORT 176 %token SIZEOF 177 %token SIZEOF_HEADERS /* SIZEOF_HEADERS, sizeof_headers */ 178 %token SORT_BY_ALIGNMENT 179 %token SORT_BY_INIT_PRIORITY 180 %token SORT_BY_NAME 181 %token SPECIAL 182 %token SQUAD 183 %token STARTUP 184 %token SUBALIGN 185 %token SYSLIB 186 %token TARGET_K /* TARGET */ 187 %token TRUNCATE 188 %token VERSIONK /* VERSION */ 189 190 /* Keywords, part 2. These are keywords that are unique to gold, 191 and not present in the old GNU linker. As before, unless the 192 comments say otherwise, the keyword is recognized as the token 193 name in upper case. */ 194 195 %token OPTION 196 197 /* Special tokens used to tell the grammar what type of tokens we are 198 parsing. The token stream always begins with one of these tokens. 199 We do this because version scripts can appear embedded within 200 linker scripts, and because --defsym uses the expression 201 parser. */ 202 %token PARSING_LINKER_SCRIPT 203 %token PARSING_VERSION_SCRIPT 204 %token PARSING_DEFSYM 205 %token PARSING_DYNAMIC_LIST 206 %token PARSING_SECTIONS_BLOCK 207 %token PARSING_SECTION_COMMANDS 208 %token PARSING_MEMORY_DEF 209 210 /* Non-terminal types, where needed. */ 211 212 %type <expr> parse_exp exp 213 %type <expr> opt_at opt_align opt_subalign opt_fill 214 %type <output_section_header> section_header opt_address_and_section_type 215 %type <section_type> section_type 216 %type <output_section_trailer> section_trailer 217 %type <constraint> opt_constraint 218 %type <string_list> opt_phdr 219 %type <integer> data_length 220 %type <input_section_spec> input_section_no_keep 221 %type <wildcard_sections> wildcard_sections 222 %type <wildcard_section> wildcard_file wildcard_section 223 %type <string_list> exclude_names 224 %type <string> wildcard_name 225 %type <integer> phdr_type memory_attr 226 %type <phdr_info> phdr_info 227 %type <versyms> vers_defns 228 %type <versnode> vers_tag 229 %type <deplist> verdep 230 %type <string> string 231 232 %% 233 234 /* Read the special token to see what to read next. */ 235 top: 236 PARSING_LINKER_SCRIPT linker_script 237 | PARSING_VERSION_SCRIPT version_script 238 | PARSING_DEFSYM defsym_expr 239 | PARSING_DYNAMIC_LIST dynamic_list_expr 240 | PARSING_SECTIONS_BLOCK sections_block 241 | PARSING_SECTION_COMMANDS section_cmds 242 | PARSING_MEMORY_DEF memory_defs 243 ; 244 245 /* A file contains a list of commands. */ 246 linker_script: 247 linker_script file_cmd 248 | /* empty */ 249 ; 250 251 /* A command which may appear at top level of a linker script. */ 252 file_cmd: 253 EXTERN '(' extern_name_list ')' 254 | FORCE_COMMON_ALLOCATION 255 { script_set_common_allocation(closure, 1); } 256 | GROUP 257 { script_start_group(closure); } 258 '(' input_list ')' 259 { script_end_group(closure); } 260 | INHIBIT_COMMON_ALLOCATION 261 { script_set_common_allocation(closure, 0); } 262 | INPUT '(' input_list ')' 263 | MEMORY '{' memory_defs '}' 264 | OPTION '(' string ')' 265 { script_parse_option(closure, $3.value, $3.length); } 266 | OUTPUT_FORMAT '(' string ')' 267 { 268 if (!script_check_output_format(closure, $3.value, $3.length, 269 NULL, 0, NULL, 0)) 270 YYABORT; 271 } 272 | OUTPUT_FORMAT '(' string ',' string ',' string ')' 273 { 274 if (!script_check_output_format(closure, $3.value, $3.length, 275 $5.value, $5.length, 276 $7.value, $7.length)) 277 YYABORT; 278 } 279 | PHDRS '{' phdrs_defs '}' 280 | SEARCH_DIR '(' string ')' 281 { script_add_search_dir(closure, $3.value, $3.length); } 282 | SECTIONS '{' 283 { script_start_sections(closure); } 284 sections_block '}' 285 { script_finish_sections(closure); } 286 | TARGET_K '(' string ')' 287 { script_set_target(closure, $3.value, $3.length); } 288 | VERSIONK '{' 289 { script_push_lex_into_version_mode(closure); } 290 version_script '}' 291 { script_pop_lex_mode(closure); } 292 | ENTRY '(' string ')' 293 { script_set_entry(closure, $3.value, $3.length); } 294 | assignment end 295 | ASSERT_K '(' parse_exp ',' string ')' 296 { script_add_assertion(closure, $3, $5.value, $5.length); } 297 | INCLUDE string 298 { script_include_directive(PARSING_LINKER_SCRIPT, closure, 299 $2.value, $2.length); } 300 | ignore_cmd 301 | ';' 302 ; 303 304 /* Top level commands which we ignore. The GNU linker uses these to 305 select the output format, but we don't offer a choice. Ignoring 306 these is more-or-less OK since most scripts simply explicitly 307 choose the default. */ 308 ignore_cmd: 309 OUTPUT_ARCH '(' string ')' 310 ; 311 312 /* A list of external undefined symbols. We put the lexer into 313 expression mode so that commas separate names; this is what the GNU 314 linker does. */ 315 316 extern_name_list: 317 { script_push_lex_into_expression_mode(closure); } 318 extern_name_list_body 319 { script_pop_lex_mode(closure); } 320 ; 321 322 extern_name_list_body: 323 string 324 { script_add_extern(closure, $1.value, $1.length); } 325 | extern_name_list_body string 326 { script_add_extern(closure, $2.value, $2.length); } 327 | extern_name_list_body ',' string 328 { script_add_extern(closure, $3.value, $3.length); } 329 ; 330 331 /* A list of input file names. */ 332 input_list: 333 input_list_element 334 | input_list opt_comma input_list_element 335 ; 336 337 /* An input file name. */ 338 input_list_element: 339 string 340 { script_add_file(closure, $1.value, $1.length); } 341 | '-' STRING 342 { script_add_library(closure, $2.value, $2.length); } 343 | AS_NEEDED 344 { script_start_as_needed(closure); } 345 '(' input_list ')' 346 { script_end_as_needed(closure); } 347 ; 348 349 /* Commands in a SECTIONS block. */ 350 sections_block: 351 sections_block section_block_cmd 352 | /* empty */ 353 ; 354 355 /* A command which may appear within a SECTIONS block. */ 356 section_block_cmd: 357 ENTRY '(' string ')' 358 { script_set_entry(closure, $3.value, $3.length); } 359 | assignment end 360 | ASSERT_K '(' parse_exp ',' string ')' 361 { script_add_assertion(closure, $3, $5.value, $5.length); } 362 | INCLUDE string 363 { script_include_directive(PARSING_SECTIONS_BLOCK, closure, 364 $2.value, $2.length); } 365 | string section_header 366 { script_start_output_section(closure, $1.value, $1.length, &$2); } 367 '{' section_cmds '}' section_trailer 368 { script_finish_output_section(closure, &$7); } 369 ; 370 371 /* The header of an output section in a SECTIONS block--everything 372 after the name. */ 373 section_header: 374 { script_push_lex_into_expression_mode(closure); } 375 opt_address_and_section_type opt_at opt_align opt_subalign 376 { script_pop_lex_mode(closure); } 377 opt_constraint 378 { 379 $$.address = $2.address; 380 $$.section_type = $2.section_type; 381 $$.load_address = $3; 382 $$.align = $4; 383 $$.subalign = $5; 384 $$.constraint = $7; 385 } 386 ; 387 388 /* The optional address followed by the optional section type. This 389 is a separate nonterminal to avoid a shift/reduce conflict on 390 '(' in section_header. */ 391 392 opt_address_and_section_type: 393 ':' 394 { 395 $$.address = NULL; 396 $$.section_type = SCRIPT_SECTION_TYPE_NONE; 397 } 398 | '(' ')' ':' 399 { 400 $$.address = NULL; 401 $$.section_type = SCRIPT_SECTION_TYPE_NONE; 402 } 403 | exp ':' 404 { 405 $$.address = $1; 406 $$.section_type = SCRIPT_SECTION_TYPE_NONE; 407 } 408 | exp '(' ')' ':' 409 { 410 $$.address = $1; 411 $$.section_type = SCRIPT_SECTION_TYPE_NONE; 412 } 413 | '(' section_type ')' ':' 414 { 415 $$.address = NULL; 416 $$.section_type = $2; 417 } 418 | exp '(' section_type ')' ':' 419 { 420 $$.address = $1; 421 $$.section_type = $3; 422 } 423 ; 424 425 /* We only support NOLOAD. */ 426 section_type: 427 NOLOAD 428 { $$ = SCRIPT_SECTION_TYPE_NOLOAD; } 429 | DSECT 430 { 431 yyerror(closure, "DSECT section type is unsupported"); 432 $$ = SCRIPT_SECTION_TYPE_DSECT; 433 } 434 | COPY 435 { 436 yyerror(closure, "COPY section type is unsupported"); 437 $$ = SCRIPT_SECTION_TYPE_COPY; 438 } 439 | INFO 440 { 441 yyerror(closure, "INFO section type is unsupported"); 442 $$ = SCRIPT_SECTION_TYPE_INFO; 443 } 444 | OVERLAY 445 { 446 yyerror(closure, "OVERLAY section type is unsupported"); 447 $$ = SCRIPT_SECTION_TYPE_OVERLAY; 448 } 449 ; 450 451 /* The address at which an output section should be loaded. */ 452 opt_at: 453 /* empty */ 454 { $$ = NULL; } 455 | AT '(' exp ')' 456 { $$ = $3; } 457 ; 458 459 /* The alignment of an output section. */ 460 opt_align: 461 /* empty */ 462 { $$ = NULL; } 463 | ALIGN_K '(' exp ')' 464 { $$ = $3; } 465 ; 466 467 /* The input section alignment within an output section. */ 468 opt_subalign: 469 /* empty */ 470 { $$ = NULL; } 471 | SUBALIGN '(' exp ')' 472 { $$ = $3; } 473 ; 474 475 /* A section constraint. */ 476 opt_constraint: 477 /* empty */ 478 { $$ = CONSTRAINT_NONE; } 479 | ONLY_IF_RO 480 { $$ = CONSTRAINT_ONLY_IF_RO; } 481 | ONLY_IF_RW 482 { $$ = CONSTRAINT_ONLY_IF_RW; } 483 | SPECIAL 484 { $$ = CONSTRAINT_SPECIAL; } 485 ; 486 487 /* The trailer of an output section in a SECTIONS block. */ 488 section_trailer: 489 opt_memspec opt_at_memspec opt_phdr opt_fill opt_comma 490 { 491 $$.fill = $4; 492 $$.phdrs = $3; 493 } 494 ; 495 496 /* A memory specification for an output section. */ 497 opt_memspec: 498 '>' string 499 { script_set_section_region(closure, $2.value, $2.length, 1); } 500 | /* empty */ 501 ; 502 503 /* A memory specification for where to load an output section. */ 504 opt_at_memspec: 505 AT '>' string 506 { script_set_section_region(closure, $3.value, $3.length, 0); } 507 | /* empty */ 508 ; 509 510 /* The program segment an output section should go into. */ 511 opt_phdr: 512 opt_phdr ':' string 513 { $$ = script_string_list_push_back($1, $3.value, $3.length); } 514 | /* empty */ 515 { $$ = NULL; } 516 ; 517 518 /* The value to use to fill an output section. FIXME: This does not 519 handle a string of arbitrary length. */ 520 opt_fill: 521 '=' parse_exp 522 { $$ = $2; } 523 | /* empty */ 524 { $$ = NULL; } 525 ; 526 527 /* Commands which may appear within the description of an output 528 section in a SECTIONS block. */ 529 section_cmds: 530 /* empty */ 531 | section_cmds section_cmd 532 ; 533 534 /* A command which may appear within the description of an output 535 section in a SECTIONS block. */ 536 section_cmd: 537 assignment end 538 | input_section_spec 539 | data_length '(' parse_exp ')' 540 { script_add_data(closure, $1, $3); } 541 | ASSERT_K '(' parse_exp ',' string ')' 542 { script_add_assertion(closure, $3, $5.value, $5.length); } 543 | FILL '(' parse_exp ')' 544 { script_add_fill(closure, $3); } 545 | CONSTRUCTORS 546 { 547 /* The GNU linker uses CONSTRUCTORS for the a.out object 548 file format. It does nothing when using ELF. Since 549 some ELF linker scripts use it although it does 550 nothing, we accept it and ignore it. */ 551 } 552 | SORT_BY_NAME '(' CONSTRUCTORS ')' 553 | INCLUDE string 554 { script_include_directive(PARSING_SECTION_COMMANDS, closure, 555 $2.value, $2.length); } 556 | ';' 557 ; 558 559 /* The length of data which may appear within the description of an 560 output section in a SECTIONS block. */ 561 data_length: 562 QUAD 563 { $$ = QUAD; } 564 | SQUAD 565 { $$ = SQUAD; } 566 | LONG 567 { $$ = LONG; } 568 | SHORT 569 { $$ = SHORT; } 570 | BYTE 571 { $$ = BYTE; } 572 ; 573 574 /* An input section specification. This may appear within the 575 description of an output section in a SECTIONS block. */ 576 input_section_spec: 577 input_section_no_keep 578 { script_add_input_section(closure, &$1, 0); } 579 | KEEP '(' input_section_no_keep ')' 580 { script_add_input_section(closure, &$3, 1); } 581 ; 582 583 /* An input section specification within a KEEP clause. */ 584 input_section_no_keep: 585 string 586 { 587 $$.file.name = $1; 588 $$.file.sort = SORT_WILDCARD_NONE; 589 $$.input_sections.sections = NULL; 590 $$.input_sections.exclude = NULL; 591 } 592 | wildcard_file '(' wildcard_sections ')' 593 { 594 $$.file = $1; 595 $$.input_sections = $3; 596 } 597 ; 598 599 /* A wildcard file specification. */ 600 wildcard_file: 601 wildcard_name 602 { 603 $$.name = $1; 604 $$.sort = SORT_WILDCARD_NONE; 605 } 606 | SORT_BY_NAME '(' wildcard_name ')' 607 { 608 $$.name = $3; 609 $$.sort = SORT_WILDCARD_BY_NAME; 610 } 611 ; 612 613 /* A list of wild card section specifications. */ 614 wildcard_sections: 615 wildcard_sections opt_comma wildcard_section 616 { 617 $$.sections = script_string_sort_list_add($1.sections, &$3); 618 $$.exclude = $1.exclude; 619 } 620 | wildcard_section 621 { 622 $$.sections = script_new_string_sort_list(&$1); 623 $$.exclude = NULL; 624 } 625 | wildcard_sections opt_comma EXCLUDE_FILE '(' exclude_names ')' 626 { 627 $$.sections = $1.sections; 628 $$.exclude = script_string_list_append($1.exclude, $5); 629 } 630 | EXCLUDE_FILE '(' exclude_names ')' 631 { 632 $$.sections = NULL; 633 $$.exclude = $3; 634 } 635 ; 636 637 /* A single wild card specification. */ 638 wildcard_section: 639 wildcard_name 640 { 641 $$.name = $1; 642 $$.sort = SORT_WILDCARD_NONE; 643 } 644 | SORT_BY_NAME '(' wildcard_section ')' 645 { 646 $$.name = $3.name; 647 switch ($3.sort) 648 { 649 case SORT_WILDCARD_NONE: 650 $$.sort = SORT_WILDCARD_BY_NAME; 651 break; 652 case SORT_WILDCARD_BY_NAME: 653 case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT: 654 break; 655 case SORT_WILDCARD_BY_ALIGNMENT: 656 case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME: 657 $$.sort = SORT_WILDCARD_BY_NAME_BY_ALIGNMENT; 658 break; 659 default: 660 abort(); 661 } 662 } 663 | SORT_BY_ALIGNMENT '(' wildcard_section ')' 664 { 665 $$.name = $3.name; 666 switch ($3.sort) 667 { 668 case SORT_WILDCARD_NONE: 669 $$.sort = SORT_WILDCARD_BY_ALIGNMENT; 670 break; 671 case SORT_WILDCARD_BY_ALIGNMENT: 672 case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME: 673 break; 674 case SORT_WILDCARD_BY_NAME: 675 case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT: 676 $$.sort = SORT_WILDCARD_BY_ALIGNMENT_BY_NAME; 677 break; 678 default: 679 abort(); 680 } 681 } 682 | SORT_BY_INIT_PRIORITY '(' wildcard_name ')' 683 { 684 $$.name = $3; 685 $$.sort = SORT_WILDCARD_BY_INIT_PRIORITY; 686 } 687 ; 688 689 /* A list of file names to exclude. */ 690 exclude_names: 691 exclude_names opt_comma wildcard_name 692 { $$ = script_string_list_push_back($1, $3.value, $3.length); } 693 | wildcard_name 694 { $$ = script_new_string_list($1.value, $1.length); } 695 ; 696 697 /* A single wildcard name. We recognize '*' and '?' specially since 698 they are expression tokens. */ 699 wildcard_name: 700 string 701 { $$ = $1; } 702 | '*' 703 { 704 $$.value = "*"; 705 $$.length = 1; 706 } 707 | '?' 708 { 709 $$.value = "?"; 710 $$.length = 1; 711 } 712 ; 713 714 /* A list of MEMORY definitions. */ 715 memory_defs: 716 memory_defs opt_comma memory_def 717 | /* empty */ 718 ; 719 720 /* A single MEMORY definition. */ 721 memory_def: 722 string memory_attr ':' memory_origin '=' parse_exp opt_comma memory_length '=' parse_exp 723 { script_add_memory(closure, $1.value, $1.length, $2, $6, $10); } 724 | 725 INCLUDE string 726 { script_include_directive(PARSING_MEMORY_DEF, closure, 727 $2.value, $2.length); } 728 | 729 ; 730 731 /* The (optional) attributes of a MEMORY region. */ 732 memory_attr: 733 '(' string ')' 734 { $$ = script_parse_memory_attr(closure, $2.value, $2.length, 0); } 735 | /* Inverted attributes. */ 736 '(' '!' string ')' 737 { $$ = script_parse_memory_attr(closure, $3.value, $3.length, 1); } 738 | /* empty */ 739 { $$ = 0; } 740 ; 741 742 memory_origin: 743 ORIGIN 744 | 745 ORG 746 | 747 'o' 748 ; 749 750 memory_length: 751 LENGTH 752 | 753 LEN 754 | 755 'l' 756 ; 757 758 /* A list of program header definitions. */ 759 phdrs_defs: 760 phdrs_defs phdr_def 761 | /* empty */ 762 ; 763 764 /* A program header definition. */ 765 phdr_def: 766 string phdr_type phdr_info ';' 767 { script_add_phdr(closure, $1.value, $1.length, $2, &$3); } 768 ; 769 770 /* A program header type. The GNU linker accepts a general expression 771 here, but that would be a pain because we would have to dig into 772 the expression structure. It's unlikely that anybody uses anything 773 other than a string or a number here, so that is all we expect. */ 774 phdr_type: 775 string 776 { $$ = script_phdr_string_to_type(closure, $1.value, $1.length); } 777 | INTEGER 778 { $$ = $1; } 779 ; 780 781 /* Additional information for a program header. */ 782 phdr_info: 783 /* empty */ 784 { memset(&$$, 0, sizeof(struct Phdr_info)); } 785 | string phdr_info 786 { 787 $$ = $2; 788 if ($1.length == 7 && strncmp($1.value, "FILEHDR", 7) == 0) 789 $$.includes_filehdr = 1; 790 else 791 yyerror(closure, "PHDRS syntax error"); 792 } 793 | PHDRS phdr_info 794 { 795 $$ = $2; 796 $$.includes_phdrs = 1; 797 } 798 | string '(' INTEGER ')' phdr_info 799 { 800 $$ = $5; 801 if ($1.length == 5 && strncmp($1.value, "FLAGS", 5) == 0) 802 { 803 $$.is_flags_valid = 1; 804 $$.flags = $3; 805 } 806 else 807 yyerror(closure, "PHDRS syntax error"); 808 } 809 | AT '(' parse_exp ')' phdr_info 810 { 811 $$ = $5; 812 $$.load_address = $3; 813 } 814 ; 815 816 /* Set a symbol to a value. */ 817 assignment: 818 string '=' parse_exp 819 { script_set_symbol(closure, $1.value, $1.length, $3, 0, 0); } 820 | string PLUSEQ parse_exp 821 { 822 Expression_ptr s = script_exp_string($1.value, $1.length); 823 Expression_ptr e = script_exp_binary_add(s, $3); 824 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 825 } 826 | string MINUSEQ parse_exp 827 { 828 Expression_ptr s = script_exp_string($1.value, $1.length); 829 Expression_ptr e = script_exp_binary_sub(s, $3); 830 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 831 } 832 | string MULTEQ parse_exp 833 { 834 Expression_ptr s = script_exp_string($1.value, $1.length); 835 Expression_ptr e = script_exp_binary_mult(s, $3); 836 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 837 } 838 | string DIVEQ parse_exp 839 { 840 Expression_ptr s = script_exp_string($1.value, $1.length); 841 Expression_ptr e = script_exp_binary_div(s, $3); 842 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 843 } 844 | string LSHIFTEQ parse_exp 845 { 846 Expression_ptr s = script_exp_string($1.value, $1.length); 847 Expression_ptr e = script_exp_binary_lshift(s, $3); 848 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 849 } 850 | string RSHIFTEQ parse_exp 851 { 852 Expression_ptr s = script_exp_string($1.value, $1.length); 853 Expression_ptr e = script_exp_binary_rshift(s, $3); 854 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 855 } 856 | string ANDEQ parse_exp 857 { 858 Expression_ptr s = script_exp_string($1.value, $1.length); 859 Expression_ptr e = script_exp_binary_bitwise_and(s, $3); 860 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 861 } 862 | string OREQ parse_exp 863 { 864 Expression_ptr s = script_exp_string($1.value, $1.length); 865 Expression_ptr e = script_exp_binary_bitwise_or(s, $3); 866 script_set_symbol(closure, $1.value, $1.length, e, 0, 0); 867 } 868 | HIDDEN '(' string '=' parse_exp ')' 869 { script_set_symbol(closure, $3.value, $3.length, $5, 0, 1); } 870 | PROVIDE '(' string '=' parse_exp ')' 871 { script_set_symbol(closure, $3.value, $3.length, $5, 1, 0); } 872 | PROVIDE_HIDDEN '(' string '=' parse_exp ')' 873 { script_set_symbol(closure, $3.value, $3.length, $5, 1, 1); } 874 ; 875 876 /* Parse an expression, putting the lexer into the right mode. */ 877 parse_exp: 878 { script_push_lex_into_expression_mode(closure); } 879 exp 880 { 881 script_pop_lex_mode(closure); 882 $$ = $2; 883 } 884 ; 885 886 /* An expression. */ 887 exp: 888 '(' exp ')' 889 { $$ = $2; } 890 | '-' exp %prec UNARY 891 { $$ = script_exp_unary_minus($2); } 892 | '!' exp %prec UNARY 893 { $$ = script_exp_unary_logical_not($2); } 894 | '~' exp %prec UNARY 895 { $$ = script_exp_unary_bitwise_not($2); } 896 | '+' exp %prec UNARY 897 { $$ = $2; } 898 | exp '*' exp 899 { $$ = script_exp_binary_mult($1, $3); } 900 | exp '/' exp 901 { $$ = script_exp_binary_div($1, $3); } 902 | exp '%' exp 903 { $$ = script_exp_binary_mod($1, $3); } 904 | exp '+' exp 905 { $$ = script_exp_binary_add($1, $3); } 906 | exp '-' exp 907 { $$ = script_exp_binary_sub($1, $3); } 908 | exp LSHIFT exp 909 { $$ = script_exp_binary_lshift($1, $3); } 910 | exp RSHIFT exp 911 { $$ = script_exp_binary_rshift($1, $3); } 912 | exp EQ exp 913 { $$ = script_exp_binary_eq($1, $3); } 914 | exp NE exp 915 { $$ = script_exp_binary_ne($1, $3); } 916 | exp LE exp 917 { $$ = script_exp_binary_le($1, $3); } 918 | exp GE exp 919 { $$ = script_exp_binary_ge($1, $3); } 920 | exp '<' exp 921 { $$ = script_exp_binary_lt($1, $3); } 922 | exp '>' exp 923 { $$ = script_exp_binary_gt($1, $3); } 924 | exp '&' exp 925 { $$ = script_exp_binary_bitwise_and($1, $3); } 926 | exp '^' exp 927 { $$ = script_exp_binary_bitwise_xor($1, $3); } 928 | exp '|' exp 929 { $$ = script_exp_binary_bitwise_or($1, $3); } 930 | exp ANDAND exp 931 { $$ = script_exp_binary_logical_and($1, $3); } 932 | exp OROR exp 933 { $$ = script_exp_binary_logical_or($1, $3); } 934 | exp '?' exp ':' exp 935 { $$ = script_exp_trinary_cond($1, $3, $5); } 936 | INTEGER 937 { $$ = script_exp_integer($1); } 938 | string 939 { $$ = script_symbol(closure, $1.value, $1.length); } 940 | MAX_K '(' exp ',' exp ')' 941 { $$ = script_exp_function_max($3, $5); } 942 | MIN_K '(' exp ',' exp ')' 943 { $$ = script_exp_function_min($3, $5); } 944 | DEFINED '(' string ')' 945 { $$ = script_exp_function_defined($3.value, $3.length); } 946 | SIZEOF_HEADERS 947 { $$ = script_exp_function_sizeof_headers(); } 948 | ALIGNOF '(' string ')' 949 { $$ = script_exp_function_alignof($3.value, $3.length); } 950 | SIZEOF '(' string ')' 951 { $$ = script_exp_function_sizeof($3.value, $3.length); } 952 | ADDR '(' string ')' 953 { $$ = script_exp_function_addr($3.value, $3.length); } 954 | LOADADDR '(' string ')' 955 { $$ = script_exp_function_loadaddr($3.value, $3.length); } 956 | ORIGIN '(' string ')' 957 { $$ = script_exp_function_origin(closure, $3.value, $3.length); } 958 | LENGTH '(' string ')' 959 { $$ = script_exp_function_length(closure, $3.value, $3.length); } 960 | CONSTANT '(' string ')' 961 { $$ = script_exp_function_constant($3.value, $3.length); } 962 | ABSOLUTE '(' exp ')' 963 { $$ = script_exp_function_absolute($3); } 964 | ALIGN_K '(' exp ')' 965 { $$ = script_exp_function_align(script_exp_string(".", 1), $3); } 966 | ALIGN_K '(' exp ',' exp ')' 967 { $$ = script_exp_function_align($3, $5); } 968 | BLOCK '(' exp ')' 969 { $$ = script_exp_function_align(script_exp_string(".", 1), $3); } 970 | DATA_SEGMENT_ALIGN '(' exp ',' exp ')' 971 { 972 script_data_segment_align(closure); 973 $$ = script_exp_function_data_segment_align($3, $5); 974 } 975 | DATA_SEGMENT_RELRO_END '(' exp ',' exp ')' 976 { 977 script_data_segment_relro_end(closure); 978 $$ = script_exp_function_data_segment_relro_end($3, $5); 979 } 980 | DATA_SEGMENT_END '(' exp ')' 981 { $$ = script_exp_function_data_segment_end($3); } 982 | SEGMENT_START '(' string ',' exp ')' 983 { 984 $$ = script_exp_function_segment_start($3.value, $3.length, $5); 985 /* We need to take note of any SEGMENT_START expressions 986 because they change the behaviour of -Ttext, -Tdata and 987 -Tbss options. */ 988 script_saw_segment_start_expression(closure); 989 } 990 | ASSERT_K '(' exp ',' string ')' 991 { $$ = script_exp_function_assert($3, $5.value, $5.length); } 992 ; 993 994 /* Handle the --defsym option. */ 995 defsym_expr: 996 string '=' parse_exp 997 { script_set_symbol(closure, $1.value, $1.length, $3, 0, 0); } 998 ; 999 1000 /* Handle the --dynamic-list option. A dynamic list has the format 1001 { sym1; sym2; extern "C++" { namespace::sym3 }; }; 1002 We store the symbol we see in the "local" list; that is where 1003 Command_line::in_dynamic_list() will look to do its check. 1004 TODO(csilvers): More than one of these brace-lists can appear, and 1005 should just be merged and treated as a single list. */ 1006 dynamic_list_expr: dynamic_list_nodes ; 1007 1008 dynamic_list_nodes: 1009 dynamic_list_node 1010 | dynamic_list_nodes dynamic_list_node 1011 ; 1012 1013 dynamic_list_node: 1014 '{' vers_defns ';' '}' ';' 1015 { script_new_vers_node (closure, NULL, $2); } 1016 ; 1017 1018 /* A version script. */ 1019 version_script: 1020 vers_nodes 1021 ; 1022 1023 vers_nodes: 1024 vers_node 1025 | vers_nodes vers_node 1026 ; 1027 1028 vers_node: 1029 '{' vers_tag '}' ';' 1030 { 1031 script_register_vers_node (closure, NULL, 0, $2, NULL); 1032 } 1033 | string '{' vers_tag '}' ';' 1034 { 1035 script_register_vers_node (closure, $1.value, $1.length, $3, 1036 NULL); 1037 } 1038 | string '{' vers_tag '}' verdep ';' 1039 { 1040 script_register_vers_node (closure, $1.value, $1.length, $3, $5); 1041 } 1042 ; 1043 1044 verdep: 1045 string 1046 { 1047 $$ = script_add_vers_depend (closure, NULL, $1.value, $1.length); 1048 } 1049 | verdep string 1050 { 1051 $$ = script_add_vers_depend (closure, $1, $2.value, $2.length); 1052 } 1053 ; 1054 1055 vers_tag: 1056 /* empty */ 1057 { $$ = script_new_vers_node (closure, NULL, NULL); } 1058 | vers_defns ';' 1059 { $$ = script_new_vers_node (closure, $1, NULL); } 1060 | GLOBAL ':' vers_defns ';' 1061 { $$ = script_new_vers_node (closure, $3, NULL); } 1062 | LOCAL ':' vers_defns ';' 1063 { $$ = script_new_vers_node (closure, NULL, $3); } 1064 | GLOBAL ':' vers_defns ';' LOCAL ':' vers_defns ';' 1065 { $$ = script_new_vers_node (closure, $3, $7); } 1066 ; 1067 1068 /* Here is one of the rare places we care about the distinction 1069 between STRING and QUOTED_STRING. For QUOTED_STRING, we do exact 1070 matching on the pattern, so we pass in true for the exact_match 1071 parameter. For STRING, we do glob matching and pass in false. */ 1072 vers_defns: 1073 STRING 1074 { 1075 $$ = script_new_vers_pattern (closure, NULL, $1.value, 1076 $1.length, 0); 1077 } 1078 | QUOTED_STRING 1079 { 1080 $$ = script_new_vers_pattern (closure, NULL, $1.value, 1081 $1.length, 1); 1082 } 1083 | vers_defns ';' STRING 1084 { 1085 $$ = script_new_vers_pattern (closure, $1, $3.value, 1086 $3.length, 0); 1087 } 1088 | vers_defns ';' QUOTED_STRING 1089 { 1090 $$ = script_new_vers_pattern (closure, $1, $3.value, 1091 $3.length, 1); 1092 } 1093 | /* Push string on the language stack. */ 1094 EXTERN string '{' 1095 { version_script_push_lang (closure, $2.value, $2.length); } 1096 vers_defns opt_semicolon '}' 1097 { 1098 $$ = $5; 1099 version_script_pop_lang(closure); 1100 } 1101 | /* Push string on the language stack. This is more complicated 1102 than the other cases because we need to merge the linked-list 1103 state from the pre-EXTERN defns and the post-EXTERN defns. */ 1104 vers_defns ';' EXTERN string '{' 1105 { version_script_push_lang (closure, $4.value, $4.length); } 1106 vers_defns opt_semicolon '}' 1107 { 1108 $$ = script_merge_expressions ($1, $7); 1109 version_script_pop_lang(closure); 1110 } 1111 | EXTERN // "extern" as a symbol name 1112 { 1113 $$ = script_new_vers_pattern (closure, NULL, "extern", 1114 sizeof("extern") - 1, 1); 1115 } 1116 | vers_defns ';' EXTERN 1117 { 1118 $$ = script_new_vers_pattern (closure, $1, "extern", 1119 sizeof("extern") - 1, 1); 1120 } 1121 ; 1122 1123 /* A string can be either a STRING or a QUOTED_STRING. Almost all the 1124 time we don't care, and we use this rule. */ 1125 string: 1126 STRING 1127 { $$ = $1; } 1128 | QUOTED_STRING 1129 { $$ = $1; } 1130 ; 1131 1132 /* Some statements require a terminator, which may be a semicolon or a 1133 comma. */ 1134 end: 1135 ';' 1136 | ',' 1137 ; 1138 1139 /* An optional semicolon. */ 1140 opt_semicolon: 1141 ';' 1142 | /* empty */ 1143 ; 1144 1145 /* An optional comma. */ 1146 opt_comma: 1147 ',' 1148 | /* empty */ 1149 ; 1150 1151 %% 1152
