1 /* Output variables, constants and external declarations, for GNU compiler. 2 Copyright (C) 1987-2019 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 21 /* This file handles generation of all the assembler code 22 *except* the instructions of a function. 23 This includes declarations of variables and their initial values. 24 25 We also output the assembler code for constants stored in memory 26 and are responsible for combining constants with the same value. */ 27 28 #include "config.h" 29 #include "system.h" 30 #include "coretypes.h" 31 #include "backend.h" 32 #include "target.h" 33 #include "rtl.h" 34 #include "tree.h" 35 #include "predict.h" 36 #include "memmodel.h" 37 #include "tm_p.h" 38 #include "stringpool.h" 39 #include "regs.h" 40 #include "emit-rtl.h" 41 #include "cgraph.h" 42 #include "diagnostic-core.h" 43 #include "fold-const.h" 44 #include "stor-layout.h" 45 #include "varasm.h" 46 #include "flags.h" 47 #include "stmt.h" 48 #include "expr.h" 49 #include "expmed.h" 50 #include "output.h" 51 #include "langhooks.h" 52 #include "debug.h" 53 #include "common/common-target.h" 54 #include "stringpool.h" 55 #include "attribs.h" 56 #include "asan.h" 57 #include "rtl-iter.h" 58 #include "file-prefix-map.h" /* remap_debug_filename() */ 59 60 #ifdef XCOFF_DEBUGGING_INFO 61 #include "xcoffout.h" /* Needed for external data declarations. */ 62 #endif 63 64 /* The (assembler) name of the first globally-visible object output. */ 65 extern GTY(()) const char *first_global_object_name; 66 extern GTY(()) const char *weak_global_object_name; 67 68 const char *first_global_object_name; 69 const char *weak_global_object_name; 70 71 struct addr_const; 72 struct constant_descriptor_rtx; 73 struct rtx_constant_pool; 74 75 #define n_deferred_constants (crtl->varasm.deferred_constants) 76 77 /* Number for making the label on the next 78 constant that is stored in memory. */ 79 80 static GTY(()) int const_labelno; 81 82 /* Carry information from ASM_DECLARE_OBJECT_NAME 83 to ASM_FINISH_DECLARE_OBJECT. */ 84 85 int size_directive_output; 86 87 /* The last decl for which assemble_variable was called, 88 if it did ASM_DECLARE_OBJECT_NAME. 89 If the last call to assemble_variable didn't do that, 90 this holds 0. */ 91 92 tree last_assemble_variable_decl; 93 94 /* The following global variable indicates if the first basic block 95 in a function belongs to the cold partition or not. */ 96 97 bool first_function_block_is_cold; 98 99 /* Whether we saw any functions with no_split_stack. */ 100 101 static bool saw_no_split_stack; 102 103 static const char *strip_reg_name (const char *); 104 static int contains_pointers_p (tree); 105 #ifdef ASM_OUTPUT_EXTERNAL 106 static bool incorporeal_function_p (tree); 107 #endif 108 static void decode_addr_const (tree, struct addr_const *); 109 static hashval_t const_hash_1 (const tree); 110 static int compare_constant (const tree, const tree); 111 static void output_constant_def_contents (rtx); 112 static void output_addressed_constants (tree); 113 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT, 114 unsigned int, bool, bool); 115 static void globalize_decl (tree); 116 static bool decl_readonly_section_1 (enum section_category); 117 #ifdef BSS_SECTION_ASM_OP 118 #ifdef ASM_OUTPUT_ALIGNED_BSS 119 static void asm_output_aligned_bss (FILE *, tree, const char *, 120 unsigned HOST_WIDE_INT, int) 121 ATTRIBUTE_UNUSED; 122 #endif 123 #endif /* BSS_SECTION_ASM_OP */ 124 static void mark_weak (tree); 125 static void output_constant_pool (const char *, tree); 126 static void handle_vtv_comdat_section (section *, const_tree); 127 128 /* Well-known sections, each one associated with some sort of *_ASM_OP. */ 129 section *text_section; 130 section *data_section; 131 section *readonly_data_section; 132 section *sdata_section; 133 section *ctors_section; 134 section *dtors_section; 135 section *bss_section; 136 section *sbss_section; 137 138 /* Various forms of common section. All are guaranteed to be nonnull. */ 139 section *tls_comm_section; 140 section *comm_section; 141 section *lcomm_section; 142 143 /* A SECTION_NOSWITCH section used for declaring global BSS variables. 144 May be null. */ 145 section *bss_noswitch_section; 146 147 /* The section that holds the main exception table, when known. The section 148 is set either by the target's init_sections hook or by the first call to 149 switch_to_exception_section. */ 150 section *exception_section; 151 152 /* The section that holds the DWARF2 frame unwind information, when known. 153 The section is set either by the target's init_sections hook or by the 154 first call to switch_to_eh_frame_section. */ 155 section *eh_frame_section; 156 157 /* asm_out_file's current section. This is NULL if no section has yet 158 been selected or if we lose track of what the current section is. */ 159 section *in_section; 160 161 /* True if code for the current function is currently being directed 162 at the cold section. */ 163 bool in_cold_section_p; 164 165 /* The following global holds the "function name" for the code in the 166 cold section of a function, if hot/cold function splitting is enabled 167 and there was actually code that went into the cold section. A 168 pseudo function name is needed for the cold section of code for some 169 debugging tools that perform symbolization. */ 170 tree cold_function_name = NULL_TREE; 171 172 /* A linked list of all the unnamed sections. */ 173 static GTY(()) section *unnamed_sections; 174 175 /* Return a nonzero value if DECL has a section attribute. */ 176 #define IN_NAMED_SECTION(DECL) \ 177 (VAR_OR_FUNCTION_DECL_P (DECL) && DECL_SECTION_NAME (DECL) != NULL) 178 179 struct section_hasher : ggc_ptr_hash<section> 180 { 181 typedef const char *compare_type; 182 183 static hashval_t hash (section *); 184 static bool equal (section *, const char *); 185 }; 186 187 /* Hash table of named sections. */ 188 static GTY(()) hash_table<section_hasher> *section_htab; 189 190 struct object_block_hasher : ggc_ptr_hash<object_block> 191 { 192 typedef const section *compare_type; 193 194 static hashval_t hash (object_block *); 195 static bool equal (object_block *, const section *); 196 }; 197 198 /* A table of object_blocks, indexed by section. */ 199 static GTY(()) hash_table<object_block_hasher> *object_block_htab; 200 201 /* The next number to use for internal anchor labels. */ 202 static GTY(()) int anchor_labelno; 203 204 /* A pool of constants that can be shared between functions. */ 205 static GTY(()) struct rtx_constant_pool *shared_constant_pool; 206 207 /* Helper routines for maintaining section_htab. */ 208 209 bool 210 section_hasher::equal (section *old, const char *new_name) 211 { 212 return strcmp (old->named.name, new_name) == 0; 213 } 214 215 hashval_t 216 section_hasher::hash (section *old) 217 { 218 return htab_hash_string (old->named.name); 219 } 220 221 /* Return a hash value for section SECT. */ 222 223 static hashval_t 224 hash_section (section *sect) 225 { 226 if (sect->common.flags & SECTION_NAMED) 227 return htab_hash_string (sect->named.name); 228 return sect->common.flags & ~SECTION_DECLARED; 229 } 230 231 /* Helper routines for maintaining object_block_htab. */ 232 233 inline bool 234 object_block_hasher::equal (object_block *old, const section *new_section) 235 { 236 return old->sect == new_section; 237 } 238 239 hashval_t 240 object_block_hasher::hash (object_block *old) 241 { 242 return hash_section (old->sect); 243 } 244 245 /* Return a new unnamed section with the given fields. */ 246 247 section * 248 get_unnamed_section (unsigned int flags, void (*callback) (const void *), 249 const void *data) 250 { 251 section *sect; 252 253 sect = ggc_alloc<section> (); 254 sect->unnamed.common.flags = flags | SECTION_UNNAMED; 255 sect->unnamed.callback = callback; 256 sect->unnamed.data = data; 257 sect->unnamed.next = unnamed_sections; 258 259 unnamed_sections = sect; 260 return sect; 261 } 262 263 /* Return a SECTION_NOSWITCH section with the given fields. */ 264 265 static section * 266 get_noswitch_section (unsigned int flags, noswitch_section_callback callback) 267 { 268 section *sect; 269 270 sect = ggc_alloc<section> (); 271 sect->noswitch.common.flags = flags | SECTION_NOSWITCH; 272 sect->noswitch.callback = callback; 273 274 return sect; 275 } 276 277 /* Return the named section structure associated with NAME. Create 278 a new section with the given fields if no such structure exists. */ 279 280 section * 281 get_section (const char *name, unsigned int flags, tree decl) 282 { 283 section *sect, **slot; 284 285 slot = section_htab->find_slot_with_hash (name, htab_hash_string (name), 286 INSERT); 287 flags |= SECTION_NAMED; 288 if (*slot == NULL) 289 { 290 sect = ggc_alloc<section> (); 291 sect->named.common.flags = flags; 292 sect->named.name = ggc_strdup (name); 293 sect->named.decl = decl; 294 *slot = sect; 295 } 296 else 297 { 298 sect = *slot; 299 /* It is fine if one of the sections has SECTION_NOTYPE as long as 300 the other has none of the contrary flags (see the logic at the end 301 of default_section_type_flags, below). */ 302 if (((sect->common.flags ^ flags) & SECTION_NOTYPE) 303 && !((sect->common.flags | flags) 304 & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE 305 | (HAVE_COMDAT_GROUP ? SECTION_LINKONCE : 0)))) 306 { 307 sect->common.flags |= SECTION_NOTYPE; 308 flags |= SECTION_NOTYPE; 309 } 310 if ((sect->common.flags & ~SECTION_DECLARED) != flags 311 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0) 312 { 313 /* It is fine if one of the section flags is 314 SECTION_WRITE | SECTION_RELRO and the other has none of these 315 flags (i.e. read-only) in named sections and either the 316 section hasn't been declared yet or has been declared as writable. 317 In that case just make sure the resulting flags are 318 SECTION_WRITE | SECTION_RELRO, ie. writable only because of 319 relocations. */ 320 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO)) 321 == (SECTION_WRITE | SECTION_RELRO) 322 && (sect->common.flags 323 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO)) 324 == (flags & ~(SECTION_WRITE | SECTION_RELRO)) 325 && ((sect->common.flags & SECTION_DECLARED) == 0 326 || (sect->common.flags & SECTION_WRITE))) 327 { 328 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO); 329 return sect; 330 } 331 /* Sanity check user variables for flag changes. */ 332 if (sect->named.decl != NULL 333 && DECL_P (sect->named.decl) 334 && decl != sect->named.decl) 335 { 336 if (decl != NULL && DECL_P (decl)) 337 error ("%+qD causes a section type conflict with %qD", 338 decl, sect->named.decl); 339 else 340 error ("section type conflict with %qD", sect->named.decl); 341 inform (DECL_SOURCE_LOCATION (sect->named.decl), 342 "%qD was declared here", sect->named.decl); 343 } 344 else if (decl != NULL && DECL_P (decl)) 345 error ("%+qD causes a section type conflict", decl); 346 else 347 error ("section type conflict"); 348 /* Make sure we don't error about one section multiple times. */ 349 sect->common.flags |= SECTION_OVERRIDE; 350 } 351 } 352 return sect; 353 } 354 355 /* Return true if the current compilation mode benefits from having 356 objects grouped into blocks. */ 357 358 static bool 359 use_object_blocks_p (void) 360 { 361 return flag_section_anchors; 362 } 363 364 /* Return the object_block structure for section SECT. Create a new 365 structure if we haven't created one already. Return null if SECT 366 itself is null. Return also null for mergeable sections since 367 section anchors can't be used in mergeable sections anyway, 368 because the linker might move objects around, and using the 369 object blocks infrastructure in that case is both a waste and a 370 maintenance burden. */ 371 372 static struct object_block * 373 get_block_for_section (section *sect) 374 { 375 struct object_block *block; 376 377 if (sect == NULL) 378 return NULL; 379 380 if (sect->common.flags & SECTION_MERGE) 381 return NULL; 382 383 object_block **slot 384 = object_block_htab->find_slot_with_hash (sect, hash_section (sect), 385 INSERT); 386 block = *slot; 387 if (block == NULL) 388 { 389 block = ggc_cleared_alloc<object_block> (); 390 block->sect = sect; 391 *slot = block; 392 } 393 return block; 394 } 395 396 /* Create a symbol with label LABEL and place it at byte offset 397 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset 398 is not yet known. LABEL must be a garbage-collected string. */ 399 400 static rtx 401 create_block_symbol (const char *label, struct object_block *block, 402 HOST_WIDE_INT offset) 403 { 404 rtx symbol; 405 unsigned int size; 406 407 /* Create the extended SYMBOL_REF. */ 408 size = RTX_HDR_SIZE + sizeof (struct block_symbol); 409 symbol = (rtx) ggc_internal_alloc (size); 410 411 /* Initialize the normal SYMBOL_REF fields. */ 412 memset (symbol, 0, size); 413 PUT_CODE (symbol, SYMBOL_REF); 414 PUT_MODE (symbol, Pmode); 415 XSTR (symbol, 0) = label; 416 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO; 417 418 /* Initialize the block_symbol stuff. */ 419 SYMBOL_REF_BLOCK (symbol) = block; 420 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset; 421 422 return symbol; 423 } 424 425 /* Return a section with a particular name and with whatever SECTION_* 426 flags section_type_flags deems appropriate. The name of the section 427 is taken from NAME if nonnull, otherwise it is taken from DECL's 428 DECL_SECTION_NAME. DECL is the decl associated with the section 429 (see the section comment for details) and RELOC is as for 430 section_type_flags. */ 431 432 section * 433 get_named_section (tree decl, const char *name, int reloc) 434 { 435 unsigned int flags; 436 437 if (name == NULL) 438 { 439 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl)); 440 name = DECL_SECTION_NAME (decl); 441 } 442 443 flags = targetm.section_type_flags (decl, name, reloc); 444 return get_section (name, flags, decl); 445 } 446 447 /* Worker for resolve_unique_section. */ 448 449 static bool 450 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED) 451 { 452 n->implicit_section = true; 453 return false; 454 } 455 456 /* If required, set DECL_SECTION_NAME to a unique name. */ 457 458 void 459 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED, 460 int flag_function_or_data_sections) 461 { 462 if (DECL_SECTION_NAME (decl) == NULL 463 && targetm_common.have_named_sections 464 && (flag_function_or_data_sections 465 || DECL_COMDAT_GROUP (decl))) 466 { 467 targetm.asm_out.unique_section (decl, reloc); 468 if (DECL_SECTION_NAME (decl)) 469 symtab_node::get (decl)->call_for_symbol_and_aliases 470 (set_implicit_section, NULL, true); 471 } 472 } 473 474 #ifdef BSS_SECTION_ASM_OP 475 476 #ifdef ASM_OUTPUT_ALIGNED_BSS 477 478 /* Utility function for targets to use in implementing 479 ASM_OUTPUT_ALIGNED_BSS. 480 ??? It is believed that this function will work in most cases so such 481 support is localized here. */ 482 483 static void 484 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED, 485 const char *name, unsigned HOST_WIDE_INT size, 486 int align) 487 { 488 switch_to_section (bss_section); 489 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); 490 #ifdef ASM_DECLARE_OBJECT_NAME 491 last_assemble_variable_decl = decl; 492 ASM_DECLARE_OBJECT_NAME (file, name, decl); 493 #else 494 /* Standard thing is just output label for the object. */ 495 ASM_OUTPUT_LABEL (file, name); 496 #endif /* ASM_DECLARE_OBJECT_NAME */ 497 ASM_OUTPUT_SKIP (file, size ? size : 1); 498 } 499 500 #endif 501 502 #endif /* BSS_SECTION_ASM_OP */ 503 504 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS 505 /* Return the hot section for function DECL. Return text_section for 506 null DECLs. */ 507 508 static section * 509 hot_function_section (tree decl) 510 { 511 if (decl != NULL_TREE 512 && DECL_SECTION_NAME (decl) != NULL 513 && targetm_common.have_named_sections) 514 return get_named_section (decl, NULL, 0); 515 else 516 return text_section; 517 } 518 #endif 519 520 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL) 521 is NULL. 522 523 When DECL_SECTION_NAME is non-NULL and it is implicit section and 524 NAMED_SECTION_SUFFIX is non-NULL, then produce section called 525 concatenate the name with NAMED_SECTION_SUFFIX. 526 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */ 527 528 section * 529 get_named_text_section (tree decl, 530 const char *text_section_name, 531 const char *named_section_suffix) 532 { 533 if (decl && DECL_SECTION_NAME (decl)) 534 { 535 if (named_section_suffix) 536 { 537 const char *dsn = DECL_SECTION_NAME (decl); 538 const char *stripped_name; 539 char *name, *buffer; 540 541 name = (char *) alloca (strlen (dsn) + 1); 542 memcpy (name, dsn, 543 strlen (dsn) + 1); 544 545 stripped_name = targetm.strip_name_encoding (name); 546 547 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL)); 548 return get_named_section (decl, buffer, 0); 549 } 550 else if (symtab_node::get (decl)->implicit_section) 551 { 552 const char *name; 553 554 /* Do not try to split gnu_linkonce functions. This gets somewhat 555 slipperly. */ 556 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP) 557 return NULL; 558 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 559 name = targetm.strip_name_encoding (name); 560 return get_named_section (decl, ACONCAT ((text_section_name, ".", 561 name, NULL)), 0); 562 } 563 else 564 return NULL; 565 } 566 return get_named_section (decl, text_section_name, 0); 567 } 568 569 /* Choose named function section based on its frequency. */ 570 571 section * 572 default_function_section (tree decl, enum node_frequency freq, 573 bool startup, bool exit) 574 { 575 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG 576 /* Old GNU linkers have buggy --gc-section support, which sometimes 577 results in .gcc_except_table* sections being garbage collected. */ 578 if (decl 579 && symtab_node::get (decl)->implicit_section) 580 return NULL; 581 #endif 582 583 if (!flag_reorder_functions 584 || !targetm_common.have_named_sections) 585 return NULL; 586 /* Startup code should go to startup subsection unless it is 587 unlikely executed (this happens especially with function splitting 588 where we can split away unnecessary parts of static constructors. */ 589 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED) 590 { 591 /* If we do have a profile or(and) LTO phase is executed, we do not need 592 these ELF section. */ 593 if (!in_lto_p || !flag_profile_values) 594 return get_named_text_section (decl, ".text.startup", NULL); 595 else 596 return NULL; 597 } 598 599 /* Similarly for exit. */ 600 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED) 601 return get_named_text_section (decl, ".text.exit", NULL); 602 603 /* Group cold functions together, similarly for hot code. */ 604 switch (freq) 605 { 606 case NODE_FREQUENCY_UNLIKELY_EXECUTED: 607 return get_named_text_section (decl, ".text.unlikely", NULL); 608 case NODE_FREQUENCY_HOT: 609 /* If we do have a profile or(and) LTO phase is executed, we do not need 610 these ELF section. */ 611 if (!in_lto_p || !flag_profile_values) 612 return get_named_text_section (decl, ".text.hot", NULL); 613 /* FALLTHRU */ 614 default: 615 return NULL; 616 } 617 } 618 619 /* Return the section for function DECL. 620 621 If DECL is NULL_TREE, return the text section. We can be passed 622 NULL_TREE under some circumstances by dbxout.c at least. 623 624 If FORCE_COLD is true, return cold function section ignoring 625 the frequency info of cgraph_node. */ 626 627 static section * 628 function_section_1 (tree decl, bool force_cold) 629 { 630 section *section = NULL; 631 enum node_frequency freq = NODE_FREQUENCY_NORMAL; 632 bool startup = false, exit = false; 633 634 if (decl) 635 { 636 struct cgraph_node *node = cgraph_node::get (decl); 637 638 if (node) 639 { 640 freq = node->frequency; 641 startup = node->only_called_at_startup; 642 exit = node->only_called_at_exit; 643 } 644 } 645 if (force_cold) 646 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED; 647 648 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS 649 if (decl != NULL_TREE 650 && DECL_SECTION_NAME (decl) != NULL) 651 { 652 if (targetm.asm_out.function_section) 653 section = targetm.asm_out.function_section (decl, freq, 654 startup, exit); 655 if (section) 656 return section; 657 return get_named_section (decl, NULL, 0); 658 } 659 else 660 return targetm.asm_out.select_section 661 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED, 662 symtab_node::get (decl)->definition_alignment ()); 663 #else 664 if (targetm.asm_out.function_section) 665 section = targetm.asm_out.function_section (decl, freq, startup, exit); 666 if (section) 667 return section; 668 return hot_function_section (decl); 669 #endif 670 } 671 672 /* Return the section for function DECL. 673 674 If DECL is NULL_TREE, return the text section. We can be passed 675 NULL_TREE under some circumstances by dbxout.c at least. */ 676 677 section * 678 function_section (tree decl) 679 { 680 /* Handle cases where function splitting code decides 681 to put function entry point into unlikely executed section 682 despite the fact that the function itself is not cold 683 (i.e. it is called rarely but contains a hot loop that is 684 better to live in hot subsection for the code locality). */ 685 return function_section_1 (decl, 686 first_function_block_is_cold); 687 } 688 689 /* Return the section for the current function, take IN_COLD_SECTION_P 690 into account. */ 691 692 section * 693 current_function_section (void) 694 { 695 return function_section_1 (current_function_decl, in_cold_section_p); 696 } 697 698 /* Tell assembler to switch to unlikely-to-be-executed text section. */ 699 700 section * 701 unlikely_text_section (void) 702 { 703 return function_section_1 (current_function_decl, true); 704 } 705 706 /* When called within a function context, return true if the function 707 has been assigned a cold text section and if SECT is that section. 708 When called outside a function context, return true if SECT is the 709 default cold section. */ 710 711 bool 712 unlikely_text_section_p (section *sect) 713 { 714 return sect == function_section_1 (current_function_decl, true); 715 } 716 717 /* Switch to the other function partition (if inside of hot section 718 into cold section, otherwise into the hot section). */ 719 720 void 721 switch_to_other_text_partition (void) 722 { 723 in_cold_section_p = !in_cold_section_p; 724 switch_to_section (current_function_section ()); 725 } 726 727 /* Return the read-only data section associated with function DECL. */ 728 729 section * 730 default_function_rodata_section (tree decl) 731 { 732 if (decl != NULL_TREE && DECL_SECTION_NAME (decl)) 733 { 734 const char *name = DECL_SECTION_NAME (decl); 735 736 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP) 737 { 738 const char *dot; 739 size_t len; 740 char* rname; 741 742 dot = strchr (name + 1, '.'); 743 if (!dot) 744 dot = name; 745 len = strlen (dot) + 8; 746 rname = (char *) alloca (len); 747 748 strcpy (rname, ".rodata"); 749 strcat (rname, dot); 750 return get_section (rname, SECTION_LINKONCE, decl); 751 } 752 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */ 753 else if (DECL_COMDAT_GROUP (decl) 754 && strncmp (name, ".gnu.linkonce.t.", 16) == 0) 755 { 756 size_t len = strlen (name) + 1; 757 char *rname = (char *) alloca (len); 758 759 memcpy (rname, name, len); 760 rname[14] = 'r'; 761 return get_section (rname, SECTION_LINKONCE, decl); 762 } 763 /* For .text.foo we want to use .rodata.foo. */ 764 else if (flag_function_sections && flag_data_sections 765 && strncmp (name, ".text.", 6) == 0) 766 { 767 size_t len = strlen (name) + 1; 768 char *rname = (char *) alloca (len + 2); 769 770 memcpy (rname, ".rodata", 7); 771 memcpy (rname + 7, name + 5, len - 5); 772 return get_section (rname, 0, decl); 773 } 774 } 775 776 return readonly_data_section; 777 } 778 779 /* Return the read-only data section associated with function DECL 780 for targets where that section should be always the single 781 readonly data section. */ 782 783 section * 784 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED) 785 { 786 return readonly_data_section; 787 } 788 789 /* A subroutine of mergeable_string_section and mergeable_constant_section. */ 790 791 static const char * 792 function_mergeable_rodata_prefix (void) 793 { 794 section *s = targetm.asm_out.function_rodata_section (current_function_decl); 795 if (SECTION_STYLE (s) == SECTION_NAMED) 796 return s->named.name; 797 else 798 return targetm.asm_out.mergeable_rodata_prefix; 799 } 800 801 /* Return the section to use for string merging. */ 802 803 static section * 804 mergeable_string_section (tree decl ATTRIBUTE_UNUSED, 805 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED, 806 unsigned int flags ATTRIBUTE_UNUSED) 807 { 808 HOST_WIDE_INT len; 809 810 if (HAVE_GAS_SHF_MERGE && flag_merge_constants 811 && TREE_CODE (decl) == STRING_CST 812 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 813 && align <= 256 814 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0 815 && TREE_STRING_LENGTH (decl) == len) 816 { 817 scalar_int_mode mode; 818 unsigned int modesize; 819 const char *str; 820 HOST_WIDE_INT i; 821 int j, unit; 822 const char *prefix = function_mergeable_rodata_prefix (); 823 char *name = (char *) alloca (strlen (prefix) + 30); 824 825 mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (TREE_TYPE (decl))); 826 modesize = GET_MODE_BITSIZE (mode); 827 if (modesize >= 8 && modesize <= 256 828 && (modesize & (modesize - 1)) == 0) 829 { 830 if (align < modesize) 831 align = modesize; 832 833 if (!HAVE_LD_ALIGNED_SHF_MERGE && align > 8) 834 return readonly_data_section; 835 836 str = TREE_STRING_POINTER (decl); 837 unit = GET_MODE_SIZE (mode); 838 839 /* Check for embedded NUL characters. */ 840 for (i = 0; i < len; i += unit) 841 { 842 for (j = 0; j < unit; j++) 843 if (str[i + j] != '\0') 844 break; 845 if (j == unit) 846 break; 847 } 848 if (i == len - unit || (unit == 1 && i == len)) 849 { 850 sprintf (name, "%s.str%d.%d", prefix, 851 modesize / 8, (int) (align / 8)); 852 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS; 853 return get_section (name, flags, NULL); 854 } 855 } 856 } 857 858 return readonly_data_section; 859 } 860 861 /* Return the section to use for constant merging. */ 862 863 section * 864 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED, 865 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED, 866 unsigned int flags ATTRIBUTE_UNUSED) 867 { 868 if (HAVE_GAS_SHF_MERGE && flag_merge_constants 869 && mode != VOIDmode 870 && mode != BLKmode 871 && known_le (GET_MODE_BITSIZE (mode), align) 872 && align >= 8 873 && align <= 256 874 && (align & (align - 1)) == 0 875 && (HAVE_LD_ALIGNED_SHF_MERGE ? 1 : align == 8)) 876 { 877 const char *prefix = function_mergeable_rodata_prefix (); 878 char *name = (char *) alloca (strlen (prefix) + 30); 879 880 sprintf (name, "%s.cst%d", prefix, (int) (align / 8)); 881 flags |= (align / 8) | SECTION_MERGE; 882 return get_section (name, flags, NULL); 883 } 884 return readonly_data_section; 885 } 886 887 /* Given NAME, a putative register name, discard any customary prefixes. */ 888 889 static const char * 890 strip_reg_name (const char *name) 891 { 892 #ifdef REGISTER_PREFIX 893 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX))) 894 name += strlen (REGISTER_PREFIX); 895 #endif 896 if (name[0] == '%' || name[0] == '#') 897 name++; 898 return name; 899 } 900 901 /* The user has asked for a DECL to have a particular name. Set (or 902 change) it in such a way that we don't prefix an underscore to 903 it. */ 904 void 905 set_user_assembler_name (tree decl, const char *name) 906 { 907 char *starred = (char *) alloca (strlen (name) + 2); 908 starred[0] = '*'; 909 strcpy (starred + 1, name); 910 symtab->change_decl_assembler_name (decl, get_identifier (starred)); 911 SET_DECL_RTL (decl, NULL_RTX); 912 } 913 914 /* Decode an `asm' spec for a declaration as a register name. 915 Return the register number, or -1 if nothing specified, 916 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized, 917 or -3 if ASMSPEC is `cc' and is not recognized, 918 or -4 if ASMSPEC is `memory' and is not recognized. 919 Accept an exact spelling or a decimal number. 920 Prefixes such as % are optional. */ 921 922 int 923 decode_reg_name_and_count (const char *asmspec, int *pnregs) 924 { 925 /* Presume just one register is clobbered. */ 926 *pnregs = 1; 927 928 if (asmspec != 0) 929 { 930 int i; 931 932 /* Get rid of confusing prefixes. */ 933 asmspec = strip_reg_name (asmspec); 934 935 /* Allow a decimal number as a "register name". */ 936 for (i = strlen (asmspec) - 1; i >= 0; i--) 937 if (! ISDIGIT (asmspec[i])) 938 break; 939 if (asmspec[0] != 0 && i < 0) 940 { 941 i = atoi (asmspec); 942 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0]) 943 return i; 944 else 945 return -2; 946 } 947 948 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) 949 if (reg_names[i][0] 950 && ! strcmp (asmspec, strip_reg_name (reg_names[i]))) 951 return i; 952 953 #ifdef OVERLAPPING_REGISTER_NAMES 954 { 955 static const struct 956 { 957 const char *const name; 958 const int number; 959 const int nregs; 960 } table[] = OVERLAPPING_REGISTER_NAMES; 961 962 for (i = 0; i < (int) ARRAY_SIZE (table); i++) 963 if (table[i].name[0] 964 && ! strcmp (asmspec, table[i].name)) 965 { 966 *pnregs = table[i].nregs; 967 return table[i].number; 968 } 969 } 970 #endif /* OVERLAPPING_REGISTER_NAMES */ 971 972 #ifdef ADDITIONAL_REGISTER_NAMES 973 { 974 static const struct { const char *const name; const int number; } table[] 975 = ADDITIONAL_REGISTER_NAMES; 976 977 for (i = 0; i < (int) ARRAY_SIZE (table); i++) 978 if (table[i].name[0] 979 && ! strcmp (asmspec, table[i].name) 980 && reg_names[table[i].number][0]) 981 return table[i].number; 982 } 983 #endif /* ADDITIONAL_REGISTER_NAMES */ 984 985 if (!strcmp (asmspec, "memory")) 986 return -4; 987 988 if (!strcmp (asmspec, "cc")) 989 return -3; 990 991 return -2; 992 } 993 994 return -1; 995 } 996 997 int 998 decode_reg_name (const char *name) 999 { 1000 int count; 1001 return decode_reg_name_and_count (name, &count); 1002 } 1003 1004 1005 /* Return true if DECL's initializer is suitable for a BSS section. */ 1006 1007 bool 1008 bss_initializer_p (const_tree decl, bool named) 1009 { 1010 /* Do not put non-common constants into the .bss section, they belong in 1011 a readonly section, except when NAMED is true. */ 1012 return ((!TREE_READONLY (decl) || DECL_COMMON (decl) || named) 1013 && (DECL_INITIAL (decl) == NULL 1014 /* In LTO we have no errors in program; error_mark_node is used 1015 to mark offlined constructors. */ 1016 || (DECL_INITIAL (decl) == error_mark_node 1017 && !in_lto_p) 1018 || (flag_zero_initialized_in_bss 1019 && initializer_zerop (DECL_INITIAL (decl))))); 1020 } 1021 1022 /* Compute the alignment of variable specified by DECL. 1023 DONT_OUTPUT_DATA is from assemble_variable. */ 1024 1025 void 1026 align_variable (tree decl, bool dont_output_data) 1027 { 1028 unsigned int align = DECL_ALIGN (decl); 1029 1030 /* In the case for initialing an array whose length isn't specified, 1031 where we have not yet been able to do the layout, 1032 figure out the proper alignment now. */ 1033 if (dont_output_data && DECL_SIZE (decl) == 0 1034 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE) 1035 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))); 1036 1037 /* Some object file formats have a maximum alignment which they support. 1038 In particular, a.out format supports a maximum alignment of 4. */ 1039 if (align > MAX_OFILE_ALIGNMENT) 1040 { 1041 error ("alignment of %q+D is greater than maximum object " 1042 "file alignment %d", decl, 1043 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT); 1044 align = MAX_OFILE_ALIGNMENT; 1045 } 1046 1047 if (! DECL_USER_ALIGN (decl)) 1048 { 1049 #ifdef DATA_ABI_ALIGNMENT 1050 unsigned int data_abi_align 1051 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align); 1052 /* For backwards compatibility, don't assume the ABI alignment for 1053 TLS variables. */ 1054 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD) 1055 align = data_abi_align; 1056 #endif 1057 1058 /* On some machines, it is good to increase alignment sometimes. 1059 But as DECL_ALIGN is used both for actually emitting the variable 1060 and for code accessing the variable as guaranteed alignment, we 1061 can only increase the alignment if it is a performance optimization 1062 if the references to it must bind to the current definition. */ 1063 if (decl_binds_to_current_def_p (decl) 1064 && !DECL_VIRTUAL_P (decl)) 1065 { 1066 #ifdef DATA_ALIGNMENT 1067 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align); 1068 /* Don't increase alignment too much for TLS variables - TLS space 1069 is too precious. */ 1070 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD) 1071 align = data_align; 1072 #endif 1073 if (DECL_INITIAL (decl) != 0 1074 /* In LTO we have no errors in program; error_mark_node is used 1075 to mark offlined constructors. */ 1076 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node)) 1077 { 1078 unsigned int const_align 1079 = targetm.constant_alignment (DECL_INITIAL (decl), align); 1080 /* Don't increase alignment too much for TLS variables - TLS 1081 space is too precious. */ 1082 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD) 1083 align = const_align; 1084 } 1085 } 1086 } 1087 1088 /* Reset the alignment in case we have made it tighter, so we can benefit 1089 from it in get_pointer_alignment. */ 1090 SET_DECL_ALIGN (decl, align); 1091 } 1092 1093 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes 1094 beyond what align_variable returned. */ 1095 1096 static unsigned int 1097 get_variable_align (tree decl) 1098 { 1099 unsigned int align = DECL_ALIGN (decl); 1100 1101 /* For user aligned vars or static vars align_variable already did 1102 everything. */ 1103 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl)) 1104 return align; 1105 1106 #ifdef DATA_ABI_ALIGNMENT 1107 if (DECL_THREAD_LOCAL_P (decl)) 1108 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align); 1109 #endif 1110 1111 /* For decls that bind to the current definition, align_variable 1112 did also everything, except for not assuming ABI required alignment 1113 of TLS variables. For other vars, increase the alignment here 1114 as an optimization. */ 1115 if (!decl_binds_to_current_def_p (decl)) 1116 { 1117 /* On some machines, it is good to increase alignment sometimes. */ 1118 #ifdef DATA_ALIGNMENT 1119 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align); 1120 /* Don't increase alignment too much for TLS variables - TLS space 1121 is too precious. */ 1122 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD) 1123 align = data_align; 1124 #endif 1125 if (DECL_INITIAL (decl) != 0 1126 /* In LTO we have no errors in program; error_mark_node is used 1127 to mark offlined constructors. */ 1128 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node)) 1129 { 1130 unsigned int const_align 1131 = targetm.constant_alignment (DECL_INITIAL (decl), align); 1132 /* Don't increase alignment too much for TLS variables - TLS space 1133 is too precious. */ 1134 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD) 1135 align = const_align; 1136 } 1137 } 1138 1139 return align; 1140 } 1141 1142 /* Return the section into which the given VAR_DECL or CONST_DECL 1143 should be placed. PREFER_NOSWITCH_P is true if a noswitch 1144 section should be used wherever possible. */ 1145 1146 section * 1147 get_variable_section (tree decl, bool prefer_noswitch_p) 1148 { 1149 addr_space_t as = ADDR_SPACE_GENERIC; 1150 int reloc; 1151 varpool_node *vnode = varpool_node::get (decl); 1152 if (vnode) 1153 { 1154 vnode = vnode->ultimate_alias_target (); 1155 decl = vnode->decl; 1156 } 1157 1158 if (TREE_TYPE (decl) != error_mark_node) 1159 as = TYPE_ADDR_SPACE (TREE_TYPE (decl)); 1160 1161 /* We need the constructor to figure out reloc flag. */ 1162 if (vnode) 1163 vnode->get_constructor (); 1164 1165 if (DECL_COMMON (decl)) 1166 { 1167 /* If the decl has been given an explicit section name, or it resides 1168 in a non-generic address space, then it isn't common, and shouldn't 1169 be handled as such. */ 1170 gcc_assert (DECL_SECTION_NAME (decl) == NULL 1171 && ADDR_SPACE_GENERIC_P (as)); 1172 if (DECL_THREAD_LOCAL_P (decl)) 1173 return tls_comm_section; 1174 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl)) 1175 return comm_section; 1176 } 1177 1178 if (DECL_INITIAL (decl) == error_mark_node) 1179 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0; 1180 else if (DECL_INITIAL (decl)) 1181 reloc = compute_reloc_for_constant (DECL_INITIAL (decl)); 1182 else 1183 reloc = 0; 1184 1185 resolve_unique_section (decl, reloc, flag_data_sections); 1186 if (IN_NAMED_SECTION (decl)) 1187 { 1188 section *sect = get_named_section (decl, NULL, reloc); 1189 1190 if ((sect->common.flags & SECTION_BSS) 1191 && !bss_initializer_p (decl, true)) 1192 { 1193 error_at (DECL_SOURCE_LOCATION (decl), 1194 "only zero initializers are allowed in section %qs", 1195 sect->named.name); 1196 DECL_INITIAL (decl) = error_mark_node; 1197 } 1198 return sect; 1199 } 1200 1201 if (ADDR_SPACE_GENERIC_P (as) 1202 && !DECL_THREAD_LOCAL_P (decl) 1203 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections) 1204 && bss_initializer_p (decl)) 1205 { 1206 if (!TREE_PUBLIC (decl) 1207 && !((flag_sanitize & SANITIZE_ADDRESS) 1208 && asan_protect_global (decl))) 1209 return lcomm_section; 1210 if (bss_noswitch_section) 1211 return bss_noswitch_section; 1212 } 1213 1214 return targetm.asm_out.select_section (decl, reloc, 1215 get_variable_align (decl)); 1216 } 1217 1218 /* Return the block into which object_block DECL should be placed. */ 1219 1220 static struct object_block * 1221 get_block_for_decl (tree decl) 1222 { 1223 section *sect; 1224 1225 if (VAR_P (decl)) 1226 { 1227 /* The object must be defined in this translation unit. */ 1228 if (DECL_EXTERNAL (decl)) 1229 return NULL; 1230 1231 /* There's no point using object blocks for something that is 1232 isolated by definition. */ 1233 if (DECL_COMDAT_GROUP (decl)) 1234 return NULL; 1235 } 1236 1237 /* We can only calculate block offsets if the decl has a known 1238 constant size. */ 1239 if (DECL_SIZE_UNIT (decl) == NULL) 1240 return NULL; 1241 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))) 1242 return NULL; 1243 1244 /* Find out which section should contain DECL. We cannot put it into 1245 an object block if it requires a standalone definition. */ 1246 if (VAR_P (decl)) 1247 align_variable (decl, 0); 1248 sect = get_variable_section (decl, true); 1249 if (SECTION_STYLE (sect) == SECTION_NOSWITCH) 1250 return NULL; 1251 1252 return get_block_for_section (sect); 1253 } 1254 1255 /* Make sure block symbol SYMBOL is in block BLOCK. */ 1256 1257 static void 1258 change_symbol_block (rtx symbol, struct object_block *block) 1259 { 1260 if (block != SYMBOL_REF_BLOCK (symbol)) 1261 { 1262 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0); 1263 SYMBOL_REF_BLOCK (symbol) = block; 1264 } 1265 } 1266 1267 /* Return true if it is possible to put DECL in an object_block. */ 1268 1269 static bool 1270 use_blocks_for_decl_p (tree decl) 1271 { 1272 struct symtab_node *snode; 1273 1274 /* Only data DECLs can be placed into object blocks. */ 1275 if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL) 1276 return false; 1277 1278 /* DECL_INITIAL (decl) set to decl is a hack used for some decls that 1279 are never used from code directly and we never want object block handling 1280 for those. */ 1281 if (DECL_INITIAL (decl) == decl) 1282 return false; 1283 1284 /* If this decl is an alias, then we don't want to emit a 1285 definition. */ 1286 if (VAR_P (decl) 1287 && (snode = symtab_node::get (decl)) != NULL 1288 && snode->alias) 1289 return false; 1290 1291 return targetm.use_blocks_for_decl_p (decl); 1292 } 1293 1294 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS 1295 until we find an identifier that is not itself a transparent alias. 1296 Modify the alias passed to it by reference (and all aliases on the 1297 way to the ultimate target), such that they do not have to be 1298 followed again, and return the ultimate target of the alias 1299 chain. */ 1300 1301 static inline tree 1302 ultimate_transparent_alias_target (tree *alias) 1303 { 1304 tree target = *alias; 1305 1306 if (IDENTIFIER_TRANSPARENT_ALIAS (target)) 1307 { 1308 gcc_assert (TREE_CHAIN (target)); 1309 target = ultimate_transparent_alias_target (&TREE_CHAIN (target)); 1310 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target) 1311 && ! TREE_CHAIN (target)); 1312 *alias = target; 1313 } 1314 1315 return target; 1316 } 1317 1318 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should 1319 have static storage duration. In other words, it should not be an 1320 automatic variable, including PARM_DECLs. 1321 1322 There is, however, one exception: this function handles variables 1323 explicitly placed in a particular register by the user. 1324 1325 This is never called for PARM_DECL nodes. */ 1326 1327 void 1328 make_decl_rtl (tree decl) 1329 { 1330 const char *name = 0; 1331 int reg_number; 1332 tree id; 1333 rtx x; 1334 1335 /* Check that we are not being given an automatic variable. */ 1336 gcc_assert (TREE_CODE (decl) != PARM_DECL 1337 && TREE_CODE (decl) != RESULT_DECL); 1338 1339 /* A weak alias has TREE_PUBLIC set but not the other bits. */ 1340 gcc_assert (!VAR_P (decl) 1341 || TREE_STATIC (decl) 1342 || TREE_PUBLIC (decl) 1343 || DECL_EXTERNAL (decl) 1344 || DECL_REGISTER (decl)); 1345 1346 /* And that we were not given a type or a label. */ 1347 gcc_assert (TREE_CODE (decl) != TYPE_DECL 1348 && TREE_CODE (decl) != LABEL_DECL); 1349 1350 /* For a duplicate declaration, we can be called twice on the 1351 same DECL node. Don't discard the RTL already made. */ 1352 if (DECL_RTL_SET_P (decl)) 1353 { 1354 /* If the old RTL had the wrong mode, fix the mode. */ 1355 x = DECL_RTL (decl); 1356 if (GET_MODE (x) != DECL_MODE (decl)) 1357 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0)); 1358 1359 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl)) 1360 return; 1361 1362 /* ??? Another way to do this would be to maintain a hashed 1363 table of such critters. Instead of adding stuff to a DECL 1364 to give certain attributes to it, we could use an external 1365 hash map from DECL to set of attributes. */ 1366 1367 /* Let the target reassign the RTL if it wants. 1368 This is necessary, for example, when one machine specific 1369 decl attribute overrides another. */ 1370 targetm.encode_section_info (decl, DECL_RTL (decl), false); 1371 1372 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based 1373 on the new decl information. */ 1374 if (MEM_P (x) 1375 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF 1376 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0))) 1377 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl)); 1378 1379 return; 1380 } 1381 1382 /* If this variable belongs to the global constant pool, retrieve the 1383 pre-computed RTL or recompute it in LTO mode. */ 1384 if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl)) 1385 { 1386 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1)); 1387 return; 1388 } 1389 1390 id = DECL_ASSEMBLER_NAME (decl); 1391 name = IDENTIFIER_POINTER (id); 1392 1393 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL 1394 && DECL_REGISTER (decl)) 1395 { 1396 error ("register name not specified for %q+D", decl); 1397 } 1398 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl)) 1399 { 1400 const char *asmspec = name+1; 1401 machine_mode mode = DECL_MODE (decl); 1402 reg_number = decode_reg_name (asmspec); 1403 /* First detect errors in declaring global registers. */ 1404 if (reg_number == -1) 1405 error ("register name not specified for %q+D", decl); 1406 else if (reg_number < 0) 1407 error ("invalid register name for %q+D", decl); 1408 else if (mode == BLKmode) 1409 error ("data type of %q+D isn%'t suitable for a register", 1410 decl); 1411 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number)) 1412 error ("the register specified for %q+D cannot be accessed" 1413 " by the current target", decl); 1414 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number)) 1415 error ("the register specified for %q+D is not general enough" 1416 " to be used as a register variable", decl); 1417 else if (!targetm.hard_regno_mode_ok (reg_number, mode)) 1418 error ("register specified for %q+D isn%'t suitable for data type", 1419 decl); 1420 /* Now handle properly declared static register variables. */ 1421 else 1422 { 1423 int nregs; 1424 1425 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl)) 1426 { 1427 DECL_INITIAL (decl) = 0; 1428 error ("global register variable has initial value"); 1429 } 1430 if (TREE_THIS_VOLATILE (decl)) 1431 warning (OPT_Wvolatile_register_var, 1432 "optimization may eliminate reads and/or " 1433 "writes to register variables"); 1434 1435 /* If the user specified one of the eliminables registers here, 1436 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable 1437 confused with that register and be eliminated. This usage is 1438 somewhat suspect... */ 1439 1440 SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number)); 1441 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number; 1442 REG_USERVAR_P (DECL_RTL (decl)) = 1; 1443 1444 if (TREE_STATIC (decl)) 1445 { 1446 /* Make this register global, so not usable for anything 1447 else. */ 1448 #ifdef ASM_DECLARE_REGISTER_GLOBAL 1449 name = IDENTIFIER_POINTER (DECL_NAME (decl)); 1450 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name); 1451 #endif 1452 nregs = hard_regno_nregs (reg_number, mode); 1453 while (nregs > 0) 1454 globalize_reg (decl, reg_number + --nregs); 1455 } 1456 1457 /* As a register variable, it has no section. */ 1458 return; 1459 } 1460 /* Avoid internal errors from invalid register 1461 specifications. */ 1462 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE); 1463 DECL_HARD_REGISTER (decl) = 0; 1464 /* Also avoid SSA inconsistencies by pretending this is an external 1465 decl now. */ 1466 DECL_EXTERNAL (decl) = 1; 1467 return; 1468 } 1469 /* Now handle ordinary static variables and functions (in memory). 1470 Also handle vars declared register invalidly. */ 1471 else if (name[0] == '*') 1472 { 1473 #ifdef REGISTER_PREFIX 1474 if (strlen (REGISTER_PREFIX) != 0) 1475 { 1476 reg_number = decode_reg_name (name); 1477 if (reg_number >= 0 || reg_number == -3) 1478 error ("register name given for non-register variable %q+D", decl); 1479 } 1480 #endif 1481 } 1482 1483 /* Specifying a section attribute on a variable forces it into a 1484 non-.bss section, and thus it cannot be common. */ 1485 /* FIXME: In general this code should not be necessary because 1486 visibility pass is doing the same work. But notice_global_symbol 1487 is called early and it needs to make DECL_RTL to get the name. 1488 we take care of recomputing the DECL_RTL after visibility is changed. */ 1489 if (VAR_P (decl) 1490 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)) 1491 && DECL_SECTION_NAME (decl) != NULL 1492 && DECL_INITIAL (decl) == NULL_TREE 1493 && DECL_COMMON (decl)) 1494 DECL_COMMON (decl) = 0; 1495 1496 /* Variables can't be both common and weak. */ 1497 if (VAR_P (decl) && DECL_WEAK (decl)) 1498 DECL_COMMON (decl) = 0; 1499 1500 if (use_object_blocks_p () && use_blocks_for_decl_p (decl)) 1501 x = create_block_symbol (name, get_block_for_decl (decl), -1); 1502 else 1503 { 1504 machine_mode address_mode = Pmode; 1505 if (TREE_TYPE (decl) != error_mark_node) 1506 { 1507 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl)); 1508 address_mode = targetm.addr_space.address_mode (as); 1509 } 1510 x = gen_rtx_SYMBOL_REF (address_mode, name); 1511 } 1512 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl); 1513 SET_SYMBOL_REF_DECL (x, decl); 1514 1515 x = gen_rtx_MEM (DECL_MODE (decl), x); 1516 if (TREE_CODE (decl) != FUNCTION_DECL) 1517 set_mem_attributes (x, decl, 1); 1518 SET_DECL_RTL (decl, x); 1519 1520 /* Optionally set flags or add text to the name to record information 1521 such as that it is a function name. 1522 If the name is changed, the macro ASM_OUTPUT_LABELREF 1523 will have to know how to strip this information. */ 1524 targetm.encode_section_info (decl, DECL_RTL (decl), true); 1525 } 1526 1527 /* Like make_decl_rtl, but inhibit creation of new alias sets when 1528 calling make_decl_rtl. Also, reset DECL_RTL before returning the 1529 rtl. */ 1530 1531 rtx 1532 make_decl_rtl_for_debug (tree decl) 1533 { 1534 unsigned int save_aliasing_flag; 1535 rtx rtl; 1536 1537 if (DECL_RTL_SET_P (decl)) 1538 return DECL_RTL (decl); 1539 1540 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will 1541 call new_alias_set. If running with -fcompare-debug, sometimes 1542 we do not want to create alias sets that will throw the alias 1543 numbers off in the comparison dumps. So... clearing 1544 flag_strict_aliasing will keep new_alias_set() from creating a 1545 new set. */ 1546 save_aliasing_flag = flag_strict_aliasing; 1547 flag_strict_aliasing = 0; 1548 1549 rtl = DECL_RTL (decl); 1550 /* Reset DECL_RTL back, as various parts of the compiler expects 1551 DECL_RTL set meaning it is actually going to be output. */ 1552 SET_DECL_RTL (decl, NULL); 1553 1554 flag_strict_aliasing = save_aliasing_flag; 1555 return rtl; 1556 } 1557 1558 /* Output a string of literal assembler code 1559 for an `asm' keyword used between functions. */ 1560 1561 void 1562 assemble_asm (tree string) 1563 { 1564 const char *p; 1565 app_enable (); 1566 1567 if (TREE_CODE (string) == ADDR_EXPR) 1568 string = TREE_OPERAND (string, 0); 1569 1570 p = TREE_STRING_POINTER (string); 1571 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p); 1572 } 1573 1574 /* Write the address of the entity given by SYMBOL to SEC. */ 1575 void 1576 assemble_addr_to_section (rtx symbol, section *sec) 1577 { 1578 switch_to_section (sec); 1579 assemble_align (POINTER_SIZE); 1580 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1); 1581 } 1582 1583 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if 1584 not) section for PRIORITY. */ 1585 section * 1586 get_cdtor_priority_section (int priority, bool constructor_p) 1587 { 1588 /* Buffer conservatively large enough for the full range of a 32-bit 1589 int plus the text below. */ 1590 char buf[18]; 1591 1592 /* ??? This only works reliably with the GNU linker. */ 1593 sprintf (buf, "%s.%.5u", 1594 constructor_p ? ".ctors" : ".dtors", 1595 /* Invert the numbering so the linker puts us in the proper 1596 order; constructors are run from right to left, and the 1597 linker sorts in increasing order. */ 1598 MAX_INIT_PRIORITY - priority); 1599 return get_section (buf, SECTION_WRITE, NULL); 1600 } 1601 1602 void 1603 default_named_section_asm_out_destructor (rtx symbol, int priority) 1604 { 1605 section *sec; 1606 1607 if (priority != DEFAULT_INIT_PRIORITY) 1608 sec = get_cdtor_priority_section (priority, 1609 /*constructor_p=*/false); 1610 else 1611 sec = get_section (".dtors", SECTION_WRITE, NULL); 1612 1613 assemble_addr_to_section (symbol, sec); 1614 } 1615 1616 #ifdef DTORS_SECTION_ASM_OP 1617 void 1618 default_dtor_section_asm_out_destructor (rtx symbol, 1619 int priority ATTRIBUTE_UNUSED) 1620 { 1621 assemble_addr_to_section (symbol, dtors_section); 1622 } 1623 #endif 1624 1625 void 1626 default_named_section_asm_out_constructor (rtx symbol, int priority) 1627 { 1628 section *sec; 1629 1630 if (priority != DEFAULT_INIT_PRIORITY) 1631 sec = get_cdtor_priority_section (priority, 1632 /*constructor_p=*/true); 1633 else 1634 sec = get_section (".ctors", SECTION_WRITE, NULL); 1635 1636 assemble_addr_to_section (symbol, sec); 1637 } 1638 1639 #ifdef CTORS_SECTION_ASM_OP 1640 void 1641 default_ctor_section_asm_out_constructor (rtx symbol, 1642 int priority ATTRIBUTE_UNUSED) 1643 { 1644 assemble_addr_to_section (symbol, ctors_section); 1645 } 1646 #endif 1647 1648 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with 1649 a nonzero value if the constant pool should be output before the 1650 start of the function, or a zero value if the pool should output 1651 after the end of the function. The default is to put it before the 1652 start. */ 1653 1654 #ifndef CONSTANT_POOL_BEFORE_FUNCTION 1655 #define CONSTANT_POOL_BEFORE_FUNCTION 1 1656 #endif 1657 1658 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going 1659 to be output to assembler. 1660 Set first_global_object_name and weak_global_object_name as appropriate. */ 1661 1662 void 1663 notice_global_symbol (tree decl) 1664 { 1665 const char **t = &first_global_object_name; 1666 1667 if (first_global_object_name 1668 || !TREE_PUBLIC (decl) 1669 || DECL_EXTERNAL (decl) 1670 || !DECL_NAME (decl) 1671 || (VAR_P (decl) && DECL_HARD_REGISTER (decl)) 1672 || (TREE_CODE (decl) != FUNCTION_DECL 1673 && (!VAR_P (decl) 1674 || (DECL_COMMON (decl) 1675 && (DECL_INITIAL (decl) == 0 1676 || DECL_INITIAL (decl) == error_mark_node))))) 1677 return; 1678 1679 /* We win when global object is found, but it is useful to know about weak 1680 symbol as well so we can produce nicer unique names. */ 1681 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib) 1682 t = &weak_global_object_name; 1683 1684 if (!*t) 1685 { 1686 tree id = DECL_ASSEMBLER_NAME (decl); 1687 ultimate_transparent_alias_target (&id); 1688 *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id))); 1689 } 1690 } 1691 1692 /* If not using flag_reorder_blocks_and_partition, decide early whether the 1693 current function goes into the cold section, so that targets can use 1694 current_function_section during RTL expansion. DECL describes the 1695 function. */ 1696 1697 void 1698 decide_function_section (tree decl) 1699 { 1700 first_function_block_is_cold = false; 1701 1702 if (DECL_SECTION_NAME (decl)) 1703 { 1704 struct cgraph_node *node = cgraph_node::get (current_function_decl); 1705 /* Calls to function_section rely on first_function_block_is_cold 1706 being accurate. */ 1707 first_function_block_is_cold = (node 1708 && node->frequency 1709 == NODE_FREQUENCY_UNLIKELY_EXECUTED); 1710 } 1711 1712 in_cold_section_p = first_function_block_is_cold; 1713 } 1714 1715 /* Get the function's name, as described by its RTL. This may be 1716 different from the DECL_NAME name used in the source file. */ 1717 const char * 1718 get_fnname_from_decl (tree decl) 1719 { 1720 rtx x = DECL_RTL (decl); 1721 gcc_assert (MEM_P (x)); 1722 x = XEXP (x, 0); 1723 gcc_assert (GET_CODE (x) == SYMBOL_REF); 1724 return XSTR (x, 0); 1725 } 1726 1727 /* Output assembler code for the constant pool of a function and associated 1728 with defining the name of the function. DECL describes the function. 1729 NAME is the function's name. For the constant pool, we use the current 1730 constant pool data. */ 1731 1732 void 1733 assemble_start_function (tree decl, const char *fnname) 1734 { 1735 int align; 1736 char tmp_label[100]; 1737 bool hot_label_written = false; 1738 1739 if (crtl->has_bb_partition) 1740 { 1741 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno); 1742 crtl->subsections.hot_section_label = ggc_strdup (tmp_label); 1743 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno); 1744 crtl->subsections.cold_section_label = ggc_strdup (tmp_label); 1745 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno); 1746 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label); 1747 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno); 1748 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label); 1749 const_labelno++; 1750 cold_function_name = NULL_TREE; 1751 } 1752 else 1753 { 1754 crtl->subsections.hot_section_label = NULL; 1755 crtl->subsections.cold_section_label = NULL; 1756 crtl->subsections.hot_section_end_label = NULL; 1757 crtl->subsections.cold_section_end_label = NULL; 1758 } 1759 1760 /* The following code does not need preprocessing in the assembler. */ 1761 1762 app_disable (); 1763 1764 if (CONSTANT_POOL_BEFORE_FUNCTION) 1765 output_constant_pool (fnname, decl); 1766 1767 align = symtab_node::get (decl)->definition_alignment (); 1768 1769 /* Make sure the not and cold text (code) sections are properly 1770 aligned. This is necessary here in the case where the function 1771 has both hot and cold sections, because we don't want to re-set 1772 the alignment when the section switch happens mid-function. */ 1773 1774 if (crtl->has_bb_partition) 1775 { 1776 first_function_block_is_cold = false; 1777 1778 switch_to_section (unlikely_text_section ()); 1779 assemble_align (align); 1780 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label); 1781 1782 /* When the function starts with a cold section, we need to explicitly 1783 align the hot section and write out the hot section label. 1784 But if the current function is a thunk, we do not have a CFG. */ 1785 if (!cfun->is_thunk 1786 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION) 1787 { 1788 switch_to_section (text_section); 1789 assemble_align (align); 1790 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label); 1791 hot_label_written = true; 1792 first_function_block_is_cold = true; 1793 } 1794 in_cold_section_p = first_function_block_is_cold; 1795 } 1796 1797 1798 /* Switch to the correct text section for the start of the function. */ 1799 1800 switch_to_section (function_section (decl)); 1801 if (crtl->has_bb_partition && !hot_label_written) 1802 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label); 1803 1804 /* Tell assembler to move to target machine's alignment for functions. */ 1805 align = floor_log2 (align / BITS_PER_UNIT); 1806 if (align > 0) 1807 { 1808 ASM_OUTPUT_ALIGN (asm_out_file, align); 1809 } 1810 1811 /* Handle a user-specified function alignment. 1812 Note that we still need to align to DECL_ALIGN, as above, 1813 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */ 1814 if (! DECL_USER_ALIGN (decl) 1815 && align_functions.levels[0].log > align 1816 && optimize_function_for_speed_p (cfun)) 1817 { 1818 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN 1819 int align_log = align_functions.levels[0].log; 1820 #endif 1821 int max_skip = align_functions.levels[0].maxskip; 1822 if (flag_limit_function_alignment && crtl->max_insn_address > 0 1823 && max_skip >= crtl->max_insn_address) 1824 max_skip = crtl->max_insn_address - 1; 1825 1826 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN 1827 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip); 1828 if (max_skip == align_functions.levels[0].maxskip) 1829 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, 1830 align_functions.levels[1].log, 1831 align_functions.levels[1].maxskip); 1832 #else 1833 ASM_OUTPUT_ALIGN (asm_out_file, align_functions.levels[0].log); 1834 #endif 1835 } 1836 1837 #ifdef ASM_OUTPUT_FUNCTION_PREFIX 1838 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname); 1839 #endif 1840 1841 if (!DECL_IGNORED_P (decl)) 1842 (*debug_hooks->begin_function) (decl); 1843 1844 /* Make function name accessible from other files, if appropriate. */ 1845 1846 if (TREE_PUBLIC (decl)) 1847 { 1848 notice_global_symbol (decl); 1849 1850 globalize_decl (decl); 1851 1852 maybe_assemble_visibility (decl); 1853 } 1854 1855 if (DECL_PRESERVE_P (decl)) 1856 targetm.asm_out.mark_decl_preserved (fnname); 1857 1858 unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size; 1859 unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start; 1860 1861 tree patchable_function_entry_attr 1862 = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl)); 1863 if (patchable_function_entry_attr) 1864 { 1865 tree pp_val = TREE_VALUE (patchable_function_entry_attr); 1866 tree patchable_function_entry_value1 = TREE_VALUE (pp_val); 1867 1868 patch_area_size = tree_to_uhwi (patchable_function_entry_value1); 1869 patch_area_entry = 0; 1870 if (TREE_CHAIN (pp_val) != NULL_TREE) 1871 { 1872 tree patchable_function_entry_value2 1873 = TREE_VALUE (TREE_CHAIN (pp_val)); 1874 patch_area_entry = tree_to_uhwi (patchable_function_entry_value2); 1875 } 1876 } 1877 1878 if (patch_area_entry > patch_area_size) 1879 { 1880 if (patch_area_size > 0) 1881 warning (OPT_Wattributes, "patchable function entry > size"); 1882 patch_area_entry = 0; 1883 } 1884 1885 /* Emit the patching area before the entry label, if any. */ 1886 if (patch_area_entry > 0) 1887 targetm.asm_out.print_patchable_function_entry (asm_out_file, 1888 patch_area_entry, true); 1889 1890 /* Do any machine/system dependent processing of the function name. */ 1891 #ifdef ASM_DECLARE_FUNCTION_NAME 1892 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl); 1893 #else 1894 /* Standard thing is just output label for the function. */ 1895 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl); 1896 #endif /* ASM_DECLARE_FUNCTION_NAME */ 1897 1898 /* And the area after the label. Record it if we haven't done so yet. */ 1899 if (patch_area_size > patch_area_entry) 1900 targetm.asm_out.print_patchable_function_entry (asm_out_file, 1901 patch_area_size 1902 - patch_area_entry, 1903 patch_area_entry == 0); 1904 1905 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl))) 1906 saw_no_split_stack = true; 1907 } 1908 1909 /* Output assembler code associated with defining the size of the 1910 function. DECL describes the function. NAME is the function's name. */ 1911 1912 void 1913 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED) 1914 { 1915 #ifdef ASM_DECLARE_FUNCTION_SIZE 1916 /* We could have switched section in the middle of the function. */ 1917 if (crtl->has_bb_partition) 1918 switch_to_section (function_section (decl)); 1919 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl); 1920 #endif 1921 if (! CONSTANT_POOL_BEFORE_FUNCTION) 1922 { 1923 output_constant_pool (fnname, decl); 1924 switch_to_section (function_section (decl)); /* need to switch back */ 1925 } 1926 /* Output labels for end of hot/cold text sections (to be used by 1927 debug info.) */ 1928 if (crtl->has_bb_partition) 1929 { 1930 section *save_text_section; 1931 1932 save_text_section = in_section; 1933 switch_to_section (unlikely_text_section ()); 1934 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE 1935 if (cold_function_name != NULL_TREE) 1936 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file, 1937 IDENTIFIER_POINTER (cold_function_name), 1938 decl); 1939 #endif 1940 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label); 1941 if (first_function_block_is_cold) 1942 switch_to_section (text_section); 1943 else 1944 switch_to_section (function_section (decl)); 1945 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label); 1946 switch_to_section (save_text_section); 1947 } 1948 } 1949 1950 /* Assemble code to leave SIZE bytes of zeros. */ 1951 1952 void 1953 assemble_zeros (unsigned HOST_WIDE_INT size) 1954 { 1955 /* Do no output if -fsyntax-only. */ 1956 if (flag_syntax_only) 1957 return; 1958 1959 #ifdef ASM_NO_SKIP_IN_TEXT 1960 /* The `space' pseudo in the text section outputs nop insns rather than 0s, 1961 so we must output 0s explicitly in the text section. */ 1962 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0) 1963 { 1964 unsigned HOST_WIDE_INT i; 1965 for (i = 0; i < size; i++) 1966 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1); 1967 } 1968 else 1969 #endif 1970 if (size > 0) 1971 ASM_OUTPUT_SKIP (asm_out_file, size); 1972 } 1973 1974 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */ 1975 1976 void 1977 assemble_align (unsigned int align) 1978 { 1979 if (align > BITS_PER_UNIT) 1980 { 1981 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 1982 } 1983 } 1984 1985 /* Assemble a string constant with the specified C string as contents. */ 1986 1987 void 1988 assemble_string (const char *p, int size) 1989 { 1990 int pos = 0; 1991 int maximum = 2000; 1992 1993 /* If the string is very long, split it up. */ 1994 1995 while (pos < size) 1996 { 1997 int thissize = size - pos; 1998 if (thissize > maximum) 1999 thissize = maximum; 2000 2001 ASM_OUTPUT_ASCII (asm_out_file, p, thissize); 2002 2003 pos += thissize; 2004 p += thissize; 2005 } 2006 } 2007 2008 2009 /* A noswitch_section_callback for lcomm_section. */ 2010 2011 static bool 2012 emit_local (tree decl ATTRIBUTE_UNUSED, 2013 const char *name ATTRIBUTE_UNUSED, 2014 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, 2015 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) 2016 { 2017 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL 2018 unsigned int align = symtab_node::get (decl)->definition_alignment (); 2019 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, 2020 size, align); 2021 return true; 2022 #elif defined ASM_OUTPUT_ALIGNED_LOCAL 2023 unsigned int align = symtab_node::get (decl)->definition_alignment (); 2024 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align); 2025 return true; 2026 #else 2027 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); 2028 return false; 2029 #endif 2030 } 2031 2032 /* A noswitch_section_callback for bss_noswitch_section. */ 2033 2034 #if defined ASM_OUTPUT_ALIGNED_BSS 2035 static bool 2036 emit_bss (tree decl ATTRIBUTE_UNUSED, 2037 const char *name ATTRIBUTE_UNUSED, 2038 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, 2039 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) 2040 { 2041 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, 2042 get_variable_align (decl)); 2043 return true; 2044 } 2045 #endif 2046 2047 /* A noswitch_section_callback for comm_section. */ 2048 2049 static bool 2050 emit_common (tree decl ATTRIBUTE_UNUSED, 2051 const char *name ATTRIBUTE_UNUSED, 2052 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, 2053 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) 2054 { 2055 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON 2056 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, 2057 size, get_variable_align (decl)); 2058 return true; 2059 #elif defined ASM_OUTPUT_ALIGNED_COMMON 2060 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, 2061 get_variable_align (decl)); 2062 return true; 2063 #else 2064 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded); 2065 return false; 2066 #endif 2067 } 2068 2069 /* A noswitch_section_callback for tls_comm_section. */ 2070 2071 static bool 2072 emit_tls_common (tree decl ATTRIBUTE_UNUSED, 2073 const char *name ATTRIBUTE_UNUSED, 2074 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, 2075 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) 2076 { 2077 #ifdef ASM_OUTPUT_TLS_COMMON 2078 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size); 2079 return true; 2080 #else 2081 sorry ("thread-local COMMON data not implemented"); 2082 return true; 2083 #endif 2084 } 2085 2086 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT. 2087 NAME is the name of DECL's SYMBOL_REF. */ 2088 2089 static void 2090 assemble_noswitch_variable (tree decl, const char *name, section *sect, 2091 unsigned int align) 2092 { 2093 unsigned HOST_WIDE_INT size, rounded; 2094 2095 size = tree_to_uhwi (DECL_SIZE_UNIT (decl)); 2096 rounded = size; 2097 2098 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl)) 2099 size += asan_red_zone_size (size); 2100 2101 /* Don't allocate zero bytes of common, 2102 since that means "undefined external" in the linker. */ 2103 if (size == 0) 2104 rounded = 1; 2105 2106 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 2107 so that each uninitialized object starts on such a boundary. */ 2108 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1; 2109 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 2110 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 2111 2112 if (!sect->noswitch.callback (decl, name, size, rounded) 2113 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded) 2114 error ("requested alignment for %q+D is greater than " 2115 "implemented alignment of %wu", decl, rounded); 2116 } 2117 2118 /* A subroutine of assemble_variable. Output the label and contents of 2119 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA 2120 is as for assemble_variable. */ 2121 2122 static void 2123 assemble_variable_contents (tree decl, const char *name, 2124 bool dont_output_data, bool merge_strings) 2125 { 2126 /* Do any machine/system dependent processing of the object. */ 2127 #ifdef ASM_DECLARE_OBJECT_NAME 2128 last_assemble_variable_decl = decl; 2129 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl); 2130 #else 2131 /* Standard thing is just output label for the object. */ 2132 ASM_OUTPUT_LABEL (asm_out_file, name); 2133 #endif /* ASM_DECLARE_OBJECT_NAME */ 2134 2135 if (!dont_output_data) 2136 { 2137 /* Caller is supposed to use varpool_get_constructor when it wants 2138 to output the body. */ 2139 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node); 2140 if (DECL_INITIAL (decl) 2141 && DECL_INITIAL (decl) != error_mark_node 2142 && !initializer_zerop (DECL_INITIAL (decl))) 2143 /* Output the actual data. */ 2144 output_constant (DECL_INITIAL (decl), 2145 tree_to_uhwi (DECL_SIZE_UNIT (decl)), 2146 get_variable_align (decl), 2147 false, merge_strings); 2148 else 2149 /* Leave space for it. */ 2150 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl))); 2151 targetm.asm_out.decl_end (); 2152 } 2153 } 2154 2155 /* Write out assembly for the variable DECL, which is not defined in 2156 the current translation unit. */ 2157 void 2158 assemble_undefined_decl (tree decl) 2159 { 2160 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 2161 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl); 2162 } 2163 2164 /* Assemble everything that is needed for a variable or function declaration. 2165 Not used for automatic variables, and not used for function definitions. 2166 Should not be called for variables of incomplete structure type. 2167 2168 TOP_LEVEL is nonzero if this variable has file scope. 2169 AT_END is nonzero if this is the special handling, at end of compilation, 2170 to define things that have had only tentative definitions. 2171 DONT_OUTPUT_DATA if nonzero means don't actually output the 2172 initial value (that will be done by the caller). */ 2173 2174 void 2175 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED, 2176 int at_end ATTRIBUTE_UNUSED, int dont_output_data) 2177 { 2178 const char *name; 2179 rtx decl_rtl, symbol; 2180 section *sect; 2181 unsigned int align; 2182 bool asan_protected = false; 2183 2184 /* This function is supposed to handle VARIABLES. Ensure we have one. */ 2185 gcc_assert (VAR_P (decl)); 2186 2187 /* Emulated TLS had better not get this far. */ 2188 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl)); 2189 2190 last_assemble_variable_decl = 0; 2191 2192 /* Normally no need to say anything here for external references, 2193 since assemble_external is called by the language-specific code 2194 when a declaration is first seen. */ 2195 2196 if (DECL_EXTERNAL (decl)) 2197 return; 2198 2199 /* Do nothing for global register variables. */ 2200 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl))) 2201 { 2202 TREE_ASM_WRITTEN (decl) = 1; 2203 return; 2204 } 2205 2206 /* If type was incomplete when the variable was declared, 2207 see if it is complete now. */ 2208 2209 if (DECL_SIZE (decl) == 0) 2210 layout_decl (decl, 0); 2211 2212 /* Still incomplete => don't allocate it; treat the tentative defn 2213 (which is what it must have been) as an `extern' reference. */ 2214 2215 if (!dont_output_data && DECL_SIZE (decl) == 0) 2216 { 2217 error ("storage size of %q+D isn%'t known", decl); 2218 TREE_ASM_WRITTEN (decl) = 1; 2219 return; 2220 } 2221 2222 /* The first declaration of a variable that comes through this function 2223 decides whether it is global (in C, has external linkage) 2224 or local (in C, has internal linkage). So do nothing more 2225 if this function has already run. */ 2226 2227 if (TREE_ASM_WRITTEN (decl)) 2228 return; 2229 2230 /* Make sure targetm.encode_section_info is invoked before we set 2231 ASM_WRITTEN. */ 2232 decl_rtl = DECL_RTL (decl); 2233 2234 TREE_ASM_WRITTEN (decl) = 1; 2235 2236 /* Do no output if -fsyntax-only. */ 2237 if (flag_syntax_only) 2238 return; 2239 2240 if (! dont_output_data 2241 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl))) 2242 { 2243 error ("size of variable %q+D is too large", decl); 2244 return; 2245 } 2246 2247 gcc_assert (MEM_P (decl_rtl)); 2248 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF); 2249 symbol = XEXP (decl_rtl, 0); 2250 2251 /* If this symbol belongs to the tree constant pool, output the constant 2252 if it hasn't already been written. */ 2253 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol)) 2254 { 2255 tree decl = SYMBOL_REF_DECL (symbol); 2256 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl))) 2257 output_constant_def_contents (symbol); 2258 return; 2259 } 2260 2261 app_disable (); 2262 2263 name = XSTR (symbol, 0); 2264 if (TREE_PUBLIC (decl) && DECL_NAME (decl)) 2265 notice_global_symbol (decl); 2266 2267 /* Compute the alignment of this data. */ 2268 2269 align_variable (decl, dont_output_data); 2270 2271 if ((flag_sanitize & SANITIZE_ADDRESS) 2272 && asan_protect_global (decl)) 2273 { 2274 asan_protected = true; 2275 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl), 2276 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT)); 2277 } 2278 2279 set_mem_align (decl_rtl, DECL_ALIGN (decl)); 2280 2281 align = get_variable_align (decl); 2282 2283 if (TREE_PUBLIC (decl)) 2284 maybe_assemble_visibility (decl); 2285 2286 if (DECL_PRESERVE_P (decl)) 2287 targetm.asm_out.mark_decl_preserved (name); 2288 2289 /* First make the assembler name(s) global if appropriate. */ 2290 sect = get_variable_section (decl, false); 2291 if (TREE_PUBLIC (decl) 2292 && (sect->common.flags & SECTION_COMMON) == 0) 2293 globalize_decl (decl); 2294 2295 /* Output any data that we will need to use the address of. */ 2296 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node) 2297 output_addressed_constants (DECL_INITIAL (decl)); 2298 2299 /* dbxout.c needs to know this. */ 2300 if (sect && (sect->common.flags & SECTION_CODE) != 0) 2301 DECL_IN_TEXT_SECTION (decl) = 1; 2302 2303 /* If the decl is part of an object_block, make sure that the decl 2304 has been positioned within its block, but do not write out its 2305 definition yet. output_object_blocks will do that later. */ 2306 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol)) 2307 { 2308 gcc_assert (!dont_output_data); 2309 place_block_symbol (symbol); 2310 } 2311 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH) 2312 assemble_noswitch_variable (decl, name, sect, align); 2313 else 2314 { 2315 /* Special-case handling of vtv comdat sections. */ 2316 if (sect->named.name 2317 && (strcmp (sect->named.name, ".vtable_map_vars") == 0)) 2318 handle_vtv_comdat_section (sect, decl); 2319 else 2320 switch_to_section (sect); 2321 if (align > BITS_PER_UNIT) 2322 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 2323 assemble_variable_contents (decl, name, dont_output_data, 2324 (sect->common.flags & SECTION_MERGE) 2325 && (sect->common.flags & SECTION_STRINGS)); 2326 if (asan_protected) 2327 { 2328 unsigned HOST_WIDE_INT int size 2329 = tree_to_uhwi (DECL_SIZE_UNIT (decl)); 2330 assemble_zeros (asan_red_zone_size (size)); 2331 } 2332 } 2333 } 2334 2335 2336 /* Given a function declaration (FN_DECL), this function assembles the 2337 function into the .preinit_array section. */ 2338 2339 void 2340 assemble_vtv_preinit_initializer (tree fn_decl) 2341 { 2342 section *sect; 2343 unsigned flags = SECTION_WRITE; 2344 rtx symbol = XEXP (DECL_RTL (fn_decl), 0); 2345 2346 flags |= SECTION_NOTYPE; 2347 sect = get_section (".preinit_array", flags, fn_decl); 2348 switch_to_section (sect); 2349 assemble_addr_to_section (symbol, sect); 2350 } 2351 2352 /* Return 1 if type TYPE contains any pointers. */ 2353 2354 static int 2355 contains_pointers_p (tree type) 2356 { 2357 switch (TREE_CODE (type)) 2358 { 2359 case POINTER_TYPE: 2360 case REFERENCE_TYPE: 2361 /* I'm not sure whether OFFSET_TYPE needs this treatment, 2362 so I'll play safe and return 1. */ 2363 case OFFSET_TYPE: 2364 return 1; 2365 2366 case RECORD_TYPE: 2367 case UNION_TYPE: 2368 case QUAL_UNION_TYPE: 2369 { 2370 tree fields; 2371 /* For a type that has fields, see if the fields have pointers. */ 2372 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields)) 2373 if (TREE_CODE (fields) == FIELD_DECL 2374 && contains_pointers_p (TREE_TYPE (fields))) 2375 return 1; 2376 return 0; 2377 } 2378 2379 case ARRAY_TYPE: 2380 /* An array type contains pointers if its element type does. */ 2381 return contains_pointers_p (TREE_TYPE (type)); 2382 2383 default: 2384 return 0; 2385 } 2386 } 2387 2388 /* We delay assemble_external processing until 2389 the compilation unit is finalized. This is the best we can do for 2390 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay 2391 it all the way to final. See PR 17982 for further discussion. */ 2392 static GTY(()) tree pending_assemble_externals; 2393 2394 #ifdef ASM_OUTPUT_EXTERNAL 2395 /* Some targets delay some output to final using TARGET_ASM_FILE_END. 2396 As a result, assemble_external can be called after the list of externals 2397 is processed and the pointer set destroyed. */ 2398 static bool pending_assemble_externals_processed; 2399 2400 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals 2401 TREE_LIST in assemble_external. */ 2402 static hash_set<tree> *pending_assemble_externals_set; 2403 2404 /* True if DECL is a function decl for which no out-of-line copy exists. 2405 It is assumed that DECL's assembler name has been set. */ 2406 2407 static bool 2408 incorporeal_function_p (tree decl) 2409 { 2410 if (TREE_CODE (decl) == FUNCTION_DECL && fndecl_built_in_p (decl)) 2411 { 2412 const char *name; 2413 2414 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL 2415 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (decl))) 2416 return true; 2417 2418 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 2419 /* Atomic or sync builtins which have survived this far will be 2420 resolved externally and therefore are not incorporeal. */ 2421 if (strncmp (name, "__builtin_", 10) == 0) 2422 return true; 2423 } 2424 return false; 2425 } 2426 2427 /* Actually do the tests to determine if this is necessary, and invoke 2428 ASM_OUTPUT_EXTERNAL. */ 2429 static void 2430 assemble_external_real (tree decl) 2431 { 2432 rtx rtl = DECL_RTL (decl); 2433 2434 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF 2435 && !SYMBOL_REF_USED (XEXP (rtl, 0)) 2436 && !incorporeal_function_p (decl)) 2437 { 2438 /* Some systems do require some output. */ 2439 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1; 2440 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0)); 2441 } 2442 } 2443 #endif 2444 2445 void 2446 process_pending_assemble_externals (void) 2447 { 2448 #ifdef ASM_OUTPUT_EXTERNAL 2449 tree list; 2450 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list)) 2451 assemble_external_real (TREE_VALUE (list)); 2452 2453 pending_assemble_externals = 0; 2454 pending_assemble_externals_processed = true; 2455 delete pending_assemble_externals_set; 2456 #endif 2457 } 2458 2459 /* This TREE_LIST contains any weak symbol declarations waiting 2460 to be emitted. */ 2461 static GTY(()) tree weak_decls; 2462 2463 /* Output something to declare an external symbol to the assembler, 2464 and qualifiers such as weakness. (Most assemblers don't need 2465 extern declaration, so we normally output nothing.) Do nothing if 2466 DECL is not external. */ 2467 2468 void 2469 assemble_external (tree decl ATTRIBUTE_UNUSED) 2470 { 2471 /* Make sure that the ASM_OUT_FILE is open. 2472 If it's not, we should not be calling this function. */ 2473 gcc_assert (asm_out_file); 2474 2475 /* In a perfect world, the following condition would be true. 2476 Sadly, the Go front end emit assembly *from the front end*, 2477 bypassing the call graph. See PR52739. Fix before GCC 4.8. */ 2478 #if 0 2479 /* This function should only be called if we are expanding, or have 2480 expanded, to RTL. 2481 Ideally, only final.c would be calling this function, but it is 2482 not clear whether that would break things somehow. See PR 17982 2483 for further discussion. */ 2484 gcc_assert (state == EXPANSION 2485 || state == FINISHED); 2486 #endif 2487 2488 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl)) 2489 return; 2490 2491 /* We want to output annotation for weak and external symbols at 2492 very last to check if they are references or not. */ 2493 2494 if (TARGET_SUPPORTS_WEAK 2495 && DECL_WEAK (decl) 2496 /* TREE_STATIC is a weird and abused creature which is not 2497 generally the right test for whether an entity has been 2498 locally emitted, inlined or otherwise not-really-extern, but 2499 for declarations that can be weak, it happens to be 2500 match. */ 2501 && !TREE_STATIC (decl) 2502 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl)) 2503 && value_member (decl, weak_decls) == NULL_TREE) 2504 weak_decls = tree_cons (NULL, decl, weak_decls); 2505 2506 #ifdef ASM_OUTPUT_EXTERNAL 2507 if (pending_assemble_externals_processed) 2508 { 2509 assemble_external_real (decl); 2510 return; 2511 } 2512 2513 if (! pending_assemble_externals_set->add (decl)) 2514 pending_assemble_externals = tree_cons (NULL, decl, 2515 pending_assemble_externals); 2516 #endif 2517 } 2518 2519 /* Similar, for calling a library function FUN. */ 2520 2521 void 2522 assemble_external_libcall (rtx fun) 2523 { 2524 /* Declare library function name external when first used, if nec. */ 2525 if (! SYMBOL_REF_USED (fun)) 2526 { 2527 SYMBOL_REF_USED (fun) = 1; 2528 targetm.asm_out.external_libcall (fun); 2529 } 2530 } 2531 2532 /* Assemble a label named NAME. */ 2533 2534 void 2535 assemble_label (FILE *file, const char *name) 2536 { 2537 ASM_OUTPUT_LABEL (file, name); 2538 } 2539 2540 /* Set the symbol_referenced flag for ID. */ 2541 void 2542 mark_referenced (tree id) 2543 { 2544 TREE_SYMBOL_REFERENCED (id) = 1; 2545 } 2546 2547 /* Set the symbol_referenced flag for DECL and notify callgraph. */ 2548 void 2549 mark_decl_referenced (tree decl) 2550 { 2551 if (TREE_CODE (decl) == FUNCTION_DECL) 2552 { 2553 /* Extern inline functions don't become needed when referenced. 2554 If we know a method will be emitted in other TU and no new 2555 functions can be marked reachable, just use the external 2556 definition. */ 2557 struct cgraph_node *node = cgraph_node::get_create (decl); 2558 if (!DECL_EXTERNAL (decl) 2559 && !node->definition) 2560 node->mark_force_output (); 2561 } 2562 else if (VAR_P (decl)) 2563 { 2564 varpool_node *node = varpool_node::get_create (decl); 2565 /* C++ frontend use mark_decl_references to force COMDAT variables 2566 to be output that might appear dead otherwise. */ 2567 node->force_output = true; 2568 } 2569 /* else do nothing - we can get various sorts of CST nodes here, 2570 which do not need to be marked. */ 2571 } 2572 2573 2574 /* Output to FILE (an assembly file) a reference to NAME. If NAME 2575 starts with a *, the rest of NAME is output verbatim. Otherwise 2576 NAME is transformed in a target-specific way (usually by the 2577 addition of an underscore). */ 2578 2579 void 2580 assemble_name_raw (FILE *file, const char *name) 2581 { 2582 if (name[0] == '*') 2583 fputs (&name[1], file); 2584 else 2585 ASM_OUTPUT_LABELREF (file, name); 2586 } 2587 2588 /* Return NAME that should actually be emitted, looking through 2589 transparent aliases. If NAME refers to an entity that is also 2590 represented as a tree (like a function or variable), mark the entity 2591 as referenced. */ 2592 const char * 2593 assemble_name_resolve (const char *name) 2594 { 2595 const char *real_name = targetm.strip_name_encoding (name); 2596 tree id = maybe_get_identifier (real_name); 2597 2598 if (id) 2599 { 2600 tree id_orig = id; 2601 2602 mark_referenced (id); 2603 ultimate_transparent_alias_target (&id); 2604 if (id != id_orig) 2605 name = IDENTIFIER_POINTER (id); 2606 gcc_assert (! TREE_CHAIN (id)); 2607 } 2608 2609 return name; 2610 } 2611 2612 /* Like assemble_name_raw, but should be used when NAME might refer to 2613 an entity that is also represented as a tree (like a function or 2614 variable). If NAME does refer to such an entity, that entity will 2615 be marked as referenced. */ 2616 2617 void 2618 assemble_name (FILE *file, const char *name) 2619 { 2620 assemble_name_raw (file, assemble_name_resolve (name)); 2621 } 2622 2623 /* Allocate SIZE bytes writable static space with a gensym name 2624 and return an RTX to refer to its address. */ 2625 2626 rtx 2627 assemble_static_space (unsigned HOST_WIDE_INT size) 2628 { 2629 char name[17]; 2630 const char *namestring; 2631 rtx x; 2632 2633 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno); 2634 ++const_labelno; 2635 namestring = ggc_strdup (name); 2636 2637 x = gen_rtx_SYMBOL_REF (Pmode, namestring); 2638 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL; 2639 2640 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL 2641 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size, 2642 BIGGEST_ALIGNMENT); 2643 #else 2644 #ifdef ASM_OUTPUT_ALIGNED_LOCAL 2645 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT); 2646 #else 2647 { 2648 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 2649 so that each uninitialized object starts on such a boundary. */ 2650 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */ 2651 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED 2652 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1) 2653 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 2654 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 2655 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); 2656 } 2657 #endif 2658 #endif 2659 return x; 2660 } 2661 2662 /* Assemble the static constant template for function entry trampolines. 2663 This is done at most once per compilation. 2664 Returns an RTX for the address of the template. */ 2665 2666 static GTY(()) rtx initial_trampoline; 2667 2668 rtx 2669 assemble_trampoline_template (void) 2670 { 2671 char label[256]; 2672 const char *name; 2673 int align; 2674 rtx symbol; 2675 2676 gcc_assert (targetm.asm_out.trampoline_template != NULL); 2677 2678 if (initial_trampoline) 2679 return initial_trampoline; 2680 2681 /* By default, put trampoline templates in read-only data section. */ 2682 2683 #ifdef TRAMPOLINE_SECTION 2684 switch_to_section (TRAMPOLINE_SECTION); 2685 #else 2686 switch_to_section (readonly_data_section); 2687 #endif 2688 2689 /* Write the assembler code to define one. */ 2690 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT); 2691 if (align > 0) 2692 ASM_OUTPUT_ALIGN (asm_out_file, align); 2693 2694 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0); 2695 targetm.asm_out.trampoline_template (asm_out_file); 2696 2697 /* Record the rtl to refer to it. */ 2698 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0); 2699 name = ggc_strdup (label); 2700 symbol = gen_rtx_SYMBOL_REF (Pmode, name); 2701 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL; 2702 2703 initial_trampoline = gen_const_mem (BLKmode, symbol); 2704 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT); 2705 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE); 2706 2707 return initial_trampoline; 2708 } 2709 2710 /* A and B are either alignments or offsets. Return the minimum alignment 2711 that may be assumed after adding the two together. */ 2712 2713 static inline unsigned 2714 min_align (unsigned int a, unsigned int b) 2715 { 2716 return least_bit_hwi (a | b); 2717 } 2718 2719 /* Return the assembler directive for creating a given kind of integer 2720 object. SIZE is the number of bytes in the object and ALIGNED_P 2721 indicates whether it is known to be aligned. Return NULL if the 2722 assembly dialect has no such directive. 2723 2724 The returned string should be printed at the start of a new line and 2725 be followed immediately by the object's initial value. */ 2726 2727 const char * 2728 integer_asm_op (int size, int aligned_p) 2729 { 2730 struct asm_int_op *ops; 2731 2732 if (aligned_p) 2733 ops = &targetm.asm_out.aligned_op; 2734 else 2735 ops = &targetm.asm_out.unaligned_op; 2736 2737 switch (size) 2738 { 2739 case 1: 2740 return targetm.asm_out.byte_op; 2741 case 2: 2742 return ops->hi; 2743 case 3: 2744 return ops->psi; 2745 case 4: 2746 return ops->si; 2747 case 5: 2748 case 6: 2749 case 7: 2750 return ops->pdi; 2751 case 8: 2752 return ops->di; 2753 case 9: 2754 case 10: 2755 case 11: 2756 case 12: 2757 case 13: 2758 case 14: 2759 case 15: 2760 return ops->pti; 2761 case 16: 2762 return ops->ti; 2763 default: 2764 return NULL; 2765 } 2766 } 2767 2768 /* Use directive OP to assemble an integer object X. Print OP at the 2769 start of the line, followed immediately by the value of X. */ 2770 2771 void 2772 assemble_integer_with_op (const char *op, rtx x) 2773 { 2774 fputs (op, asm_out_file); 2775 output_addr_const (asm_out_file, x); 2776 fputc ('\n', asm_out_file); 2777 } 2778 2779 /* The default implementation of the asm_out.integer target hook. */ 2780 2781 bool 2782 default_assemble_integer (rtx x ATTRIBUTE_UNUSED, 2783 unsigned int size ATTRIBUTE_UNUSED, 2784 int aligned_p ATTRIBUTE_UNUSED) 2785 { 2786 const char *op = integer_asm_op (size, aligned_p); 2787 /* Avoid GAS bugs for large values. Specifically negative values whose 2788 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */ 2789 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS) 2790 return false; 2791 return op && (assemble_integer_with_op (op, x), true); 2792 } 2793 2794 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is 2795 the alignment of the integer in bits. Return 1 if we were able to output 2796 the constant, otherwise 0. We must be able to output the constant, 2797 if FORCE is nonzero. */ 2798 2799 bool 2800 assemble_integer (rtx x, unsigned int size, unsigned int align, int force) 2801 { 2802 int aligned_p; 2803 2804 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT)); 2805 2806 /* See if the target hook can handle this kind of object. */ 2807 if (targetm.asm_out.integer (x, size, aligned_p)) 2808 return true; 2809 2810 /* If the object is a multi-byte one, try splitting it up. Split 2811 it into words it if is multi-word, otherwise split it into bytes. */ 2812 if (size > 1) 2813 { 2814 machine_mode omode, imode; 2815 unsigned int subalign; 2816 unsigned int subsize, i; 2817 enum mode_class mclass; 2818 2819 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1; 2820 subalign = MIN (align, subsize * BITS_PER_UNIT); 2821 if (GET_CODE (x) == CONST_FIXED) 2822 mclass = GET_MODE_CLASS (GET_MODE (x)); 2823 else 2824 mclass = MODE_INT; 2825 2826 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require (); 2827 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require (); 2828 2829 for (i = 0; i < size; i += subsize) 2830 { 2831 rtx partial = simplify_subreg (omode, x, imode, i); 2832 if (!partial || !assemble_integer (partial, subsize, subalign, 0)) 2833 break; 2834 } 2835 if (i == size) 2836 return true; 2837 2838 /* If we've printed some of it, but not all of it, there's no going 2839 back now. */ 2840 gcc_assert (!i); 2841 } 2842 2843 gcc_assert (!force); 2844 2845 return false; 2846 } 2847 2848 /* Assemble the floating-point constant D into an object of size MODE. ALIGN 2849 is the alignment of the constant in bits. If REVERSE is true, D is output 2850 in reverse storage order. */ 2851 2852 void 2853 assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align, 2854 bool reverse) 2855 { 2856 long data[4] = {0, 0, 0, 0}; 2857 int bitsize, nelts, nunits, units_per; 2858 rtx elt; 2859 2860 /* This is hairy. We have a quantity of known size. real_to_target 2861 will put it into an array of *host* longs, 32 bits per element 2862 (even if long is more than 32 bits). We need to determine the 2863 number of array elements that are occupied (nelts) and the number 2864 of *target* min-addressable units that will be occupied in the 2865 object file (nunits). We cannot assume that 32 divides the 2866 mode's bitsize (size * BITS_PER_UNIT) evenly. 2867 2868 size * BITS_PER_UNIT is used here to make sure that padding bits 2869 (which might appear at either end of the value; real_to_target 2870 will include the padding bits in its output array) are included. */ 2871 2872 nunits = GET_MODE_SIZE (mode); 2873 bitsize = nunits * BITS_PER_UNIT; 2874 nelts = CEIL (bitsize, 32); 2875 units_per = 32 / BITS_PER_UNIT; 2876 2877 real_to_target (data, &d, mode); 2878 2879 /* Put out the first word with the specified alignment. */ 2880 if (reverse) 2881 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode)); 2882 else 2883 elt = GEN_INT (data[0]); 2884 assemble_integer (elt, MIN (nunits, units_per), align, 1); 2885 nunits -= units_per; 2886 2887 /* Subsequent words need only 32-bit alignment. */ 2888 align = min_align (align, 32); 2889 2890 for (int i = 1; i < nelts; i++) 2891 { 2892 if (reverse) 2893 elt = flip_storage_order (SImode, 2894 gen_int_mode (data[nelts - 1 - i], SImode)); 2895 else 2896 elt = GEN_INT (data[i]); 2897 assemble_integer (elt, MIN (nunits, units_per), align, 1); 2898 nunits -= units_per; 2899 } 2900 } 2901 2902 /* Given an expression EXP with a constant value, 2903 reduce it to the sum of an assembler symbol and an integer. 2904 Store them both in the structure *VALUE. 2905 EXP must be reducible. */ 2906 2907 struct addr_const { 2908 rtx base; 2909 poly_int64 offset; 2910 }; 2911 2912 static void 2913 decode_addr_const (tree exp, struct addr_const *value) 2914 { 2915 tree target = TREE_OPERAND (exp, 0); 2916 poly_int64 offset = 0; 2917 rtx x; 2918 2919 while (1) 2920 { 2921 poly_int64 bytepos; 2922 if (TREE_CODE (target) == COMPONENT_REF 2923 && poly_int_tree_p (byte_position (TREE_OPERAND (target, 1)), 2924 &bytepos)) 2925 { 2926 offset += bytepos; 2927 target = TREE_OPERAND (target, 0); 2928 } 2929 else if (TREE_CODE (target) == ARRAY_REF 2930 || TREE_CODE (target) == ARRAY_RANGE_REF) 2931 { 2932 /* Truncate big offset. */ 2933 offset 2934 += (TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (target))) 2935 * wi::to_poly_widest (TREE_OPERAND (target, 1)).force_shwi ()); 2936 target = TREE_OPERAND (target, 0); 2937 } 2938 else if (TREE_CODE (target) == MEM_REF 2939 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR) 2940 { 2941 offset += mem_ref_offset (target).force_shwi (); 2942 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0); 2943 } 2944 else if (TREE_CODE (target) == INDIRECT_REF 2945 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR 2946 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0)) 2947 == ADDR_EXPR) 2948 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0); 2949 else 2950 break; 2951 } 2952 2953 switch (TREE_CODE (target)) 2954 { 2955 case VAR_DECL: 2956 case FUNCTION_DECL: 2957 x = DECL_RTL (target); 2958 break; 2959 2960 case LABEL_DECL: 2961 x = gen_rtx_MEM (FUNCTION_MODE, 2962 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target))); 2963 break; 2964 2965 case REAL_CST: 2966 case FIXED_CST: 2967 case STRING_CST: 2968 case COMPLEX_CST: 2969 case CONSTRUCTOR: 2970 case INTEGER_CST: 2971 x = lookup_constant_def (target); 2972 /* Should have been added by output_addressed_constants. */ 2973 gcc_assert (x); 2974 break; 2975 2976 case INDIRECT_REF: 2977 /* This deals with absolute addresses. */ 2978 offset += tree_to_shwi (TREE_OPERAND (target, 0)); 2979 x = gen_rtx_MEM (QImode, 2980 gen_rtx_SYMBOL_REF (Pmode, "origin of addresses")); 2981 break; 2982 2983 case COMPOUND_LITERAL_EXPR: 2984 gcc_assert (COMPOUND_LITERAL_EXPR_DECL (target)); 2985 x = DECL_RTL (COMPOUND_LITERAL_EXPR_DECL (target)); 2986 break; 2987 2988 default: 2989 gcc_unreachable (); 2990 } 2991 2992 gcc_assert (MEM_P (x)); 2993 x = XEXP (x, 0); 2994 2995 value->base = x; 2996 value->offset = offset; 2997 } 2998 2999 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab; 3000 3001 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int); 3002 3003 /* Constant pool accessor function. */ 3004 3005 hash_table<tree_descriptor_hasher> * 3006 constant_pool_htab (void) 3007 { 3008 return const_desc_htab; 3009 } 3010 3011 /* Compute a hash code for a constant expression. */ 3012 3013 hashval_t 3014 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr) 3015 { 3016 return ptr->hash; 3017 } 3018 3019 static hashval_t 3020 const_hash_1 (const tree exp) 3021 { 3022 const char *p; 3023 hashval_t hi; 3024 int len, i; 3025 enum tree_code code = TREE_CODE (exp); 3026 3027 /* Either set P and LEN to the address and len of something to hash and 3028 exit the switch or return a value. */ 3029 3030 switch (code) 3031 { 3032 case INTEGER_CST: 3033 p = (char *) &TREE_INT_CST_ELT (exp, 0); 3034 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT); 3035 break; 3036 3037 case REAL_CST: 3038 return real_hash (TREE_REAL_CST_PTR (exp)); 3039 3040 case FIXED_CST: 3041 return fixed_hash (TREE_FIXED_CST_PTR (exp)); 3042 3043 case STRING_CST: 3044 p = TREE_STRING_POINTER (exp); 3045 len = TREE_STRING_LENGTH (exp); 3046 break; 3047 3048 case COMPLEX_CST: 3049 return (const_hash_1 (TREE_REALPART (exp)) * 5 3050 + const_hash_1 (TREE_IMAGPART (exp))); 3051 3052 case VECTOR_CST: 3053 { 3054 hi = 7 + VECTOR_CST_NPATTERNS (exp); 3055 hi = hi * 563 + VECTOR_CST_NELTS_PER_PATTERN (exp); 3056 unsigned int count = vector_cst_encoded_nelts (exp); 3057 for (unsigned int i = 0; i < count; ++i) 3058 hi = hi * 563 + const_hash_1 (VECTOR_CST_ENCODED_ELT (exp, i)); 3059 return hi; 3060 } 3061 3062 case CONSTRUCTOR: 3063 { 3064 unsigned HOST_WIDE_INT idx; 3065 tree value; 3066 3067 hi = 5 + int_size_in_bytes (TREE_TYPE (exp)); 3068 3069 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value) 3070 if (value) 3071 hi = hi * 603 + const_hash_1 (value); 3072 3073 return hi; 3074 } 3075 3076 case ADDR_EXPR: 3077 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0))) 3078 return const_hash_1 (TREE_OPERAND (exp, 0)); 3079 3080 /* Fallthru. */ 3081 case FDESC_EXPR: 3082 { 3083 struct addr_const value; 3084 3085 decode_addr_const (exp, &value); 3086 switch (GET_CODE (value.base)) 3087 { 3088 case SYMBOL_REF: 3089 /* Don't hash the address of the SYMBOL_REF; 3090 only use the offset and the symbol name. */ 3091 hi = value.offset.coeffs[0]; 3092 p = XSTR (value.base, 0); 3093 for (i = 0; p[i] != 0; i++) 3094 hi = ((hi * 613) + (unsigned) (p[i])); 3095 break; 3096 3097 case LABEL_REF: 3098 hi = (value.offset.coeffs[0] 3099 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13); 3100 break; 3101 3102 default: 3103 gcc_unreachable (); 3104 } 3105 } 3106 return hi; 3107 3108 case PLUS_EXPR: 3109 case POINTER_PLUS_EXPR: 3110 case MINUS_EXPR: 3111 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9 3112 + const_hash_1 (TREE_OPERAND (exp, 1))); 3113 3114 CASE_CONVERT: 3115 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2; 3116 3117 default: 3118 /* A language specific constant. Just hash the code. */ 3119 return code; 3120 } 3121 3122 /* Compute hashing function. */ 3123 hi = len; 3124 for (i = 0; i < len; i++) 3125 hi = ((hi * 613) + (unsigned) (p[i])); 3126 3127 return hi; 3128 } 3129 3130 /* Wrapper of compare_constant, for the htab interface. */ 3131 bool 3132 tree_descriptor_hasher::equal (constant_descriptor_tree *c1, 3133 constant_descriptor_tree *c2) 3134 { 3135 if (c1->hash != c2->hash) 3136 return 0; 3137 return compare_constant (c1->value, c2->value); 3138 } 3139 3140 /* Compare t1 and t2, and return 1 only if they are known to result in 3141 the same bit pattern on output. */ 3142 3143 static int 3144 compare_constant (const tree t1, const tree t2) 3145 { 3146 enum tree_code typecode; 3147 3148 if (t1 == NULL_TREE) 3149 return t2 == NULL_TREE; 3150 if (t2 == NULL_TREE) 3151 return 0; 3152 3153 if (TREE_CODE (t1) != TREE_CODE (t2)) 3154 return 0; 3155 3156 switch (TREE_CODE (t1)) 3157 { 3158 case INTEGER_CST: 3159 /* Integer constants are the same only if the same width of type. */ 3160 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2))) 3161 return 0; 3162 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))) 3163 return 0; 3164 return tree_int_cst_equal (t1, t2); 3165 3166 case REAL_CST: 3167 /* Real constants are the same only if the same width of type. In 3168 addition to the same width, we need to check whether the modes are the 3169 same. There might be two floating point modes that are the same size 3170 but have different representations, such as the PowerPC that has 2 3171 different 128-bit floating point types (IBM extended double and IEEE 3172 128-bit floating point). */ 3173 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2))) 3174 return 0; 3175 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))) 3176 return 0; 3177 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2)); 3178 3179 case FIXED_CST: 3180 /* Fixed constants are the same only if the same width of type. */ 3181 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2))) 3182 return 0; 3183 3184 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2)); 3185 3186 case STRING_CST: 3187 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)) 3188 || int_size_in_bytes (TREE_TYPE (t1)) 3189 != int_size_in_bytes (TREE_TYPE (t2))) 3190 return 0; 3191 3192 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2) 3193 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2), 3194 TREE_STRING_LENGTH (t1))); 3195 3196 case COMPLEX_CST: 3197 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2)) 3198 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2))); 3199 3200 case VECTOR_CST: 3201 { 3202 if (VECTOR_CST_NPATTERNS (t1) 3203 != VECTOR_CST_NPATTERNS (t2)) 3204 return 0; 3205 3206 if (VECTOR_CST_NELTS_PER_PATTERN (t1) 3207 != VECTOR_CST_NELTS_PER_PATTERN (t2)) 3208 return 0; 3209 3210 unsigned int count = vector_cst_encoded_nelts (t1); 3211 for (unsigned int i = 0; i < count; ++i) 3212 if (!compare_constant (VECTOR_CST_ENCODED_ELT (t1, i), 3213 VECTOR_CST_ENCODED_ELT (t2, i))) 3214 return 0; 3215 3216 return 1; 3217 } 3218 3219 case CONSTRUCTOR: 3220 { 3221 vec<constructor_elt, va_gc> *v1, *v2; 3222 unsigned HOST_WIDE_INT idx; 3223 3224 typecode = TREE_CODE (TREE_TYPE (t1)); 3225 if (typecode != TREE_CODE (TREE_TYPE (t2))) 3226 return 0; 3227 3228 if (typecode == ARRAY_TYPE) 3229 { 3230 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1)); 3231 /* For arrays, check that mode, size and storage order match. */ 3232 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)) 3233 || size_1 == -1 3234 || size_1 != int_size_in_bytes (TREE_TYPE (t2)) 3235 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1)) 3236 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2))) 3237 return 0; 3238 } 3239 else 3240 { 3241 /* For record and union constructors, require exact type 3242 equality. */ 3243 if (TREE_TYPE (t1) != TREE_TYPE (t2)) 3244 return 0; 3245 } 3246 3247 v1 = CONSTRUCTOR_ELTS (t1); 3248 v2 = CONSTRUCTOR_ELTS (t2); 3249 if (vec_safe_length (v1) != vec_safe_length (v2)) 3250 return 0; 3251 3252 for (idx = 0; idx < vec_safe_length (v1); ++idx) 3253 { 3254 constructor_elt *c1 = &(*v1)[idx]; 3255 constructor_elt *c2 = &(*v2)[idx]; 3256 3257 /* Check that each value is the same... */ 3258 if (!compare_constant (c1->value, c2->value)) 3259 return 0; 3260 /* ... and that they apply to the same fields! */ 3261 if (typecode == ARRAY_TYPE) 3262 { 3263 if (!compare_constant (c1->index, c2->index)) 3264 return 0; 3265 } 3266 else 3267 { 3268 if (c1->index != c2->index) 3269 return 0; 3270 } 3271 } 3272 3273 return 1; 3274 } 3275 3276 case ADDR_EXPR: 3277 case FDESC_EXPR: 3278 { 3279 struct addr_const value1, value2; 3280 enum rtx_code code; 3281 int ret; 3282 3283 decode_addr_const (t1, &value1); 3284 decode_addr_const (t2, &value2); 3285 3286 if (maybe_ne (value1.offset, value2.offset)) 3287 return 0; 3288 3289 code = GET_CODE (value1.base); 3290 if (code != GET_CODE (value2.base)) 3291 return 0; 3292 3293 switch (code) 3294 { 3295 case SYMBOL_REF: 3296 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0); 3297 break; 3298 3299 case LABEL_REF: 3300 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base)) 3301 == CODE_LABEL_NUMBER (label_ref_label (value2.base))); 3302 break; 3303 3304 default: 3305 gcc_unreachable (); 3306 } 3307 return ret; 3308 } 3309 3310 case PLUS_EXPR: 3311 case POINTER_PLUS_EXPR: 3312 case MINUS_EXPR: 3313 case RANGE_EXPR: 3314 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0)) 3315 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1))); 3316 3317 CASE_CONVERT: 3318 case VIEW_CONVERT_EXPR: 3319 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0)); 3320 3321 default: 3322 return 0; 3323 } 3324 3325 gcc_unreachable (); 3326 } 3327 3328 /* Return the section into which constant EXP should be placed. */ 3329 3330 static section * 3331 get_constant_section (tree exp, unsigned int align) 3332 { 3333 return targetm.asm_out.select_section (exp, 3334 compute_reloc_for_constant (exp), 3335 align); 3336 } 3337 3338 /* Return the size of constant EXP in bytes. */ 3339 3340 static HOST_WIDE_INT 3341 get_constant_size (tree exp) 3342 { 3343 HOST_WIDE_INT size; 3344 3345 size = int_size_in_bytes (TREE_TYPE (exp)); 3346 gcc_checking_assert (size >= 0); 3347 gcc_checking_assert (TREE_CODE (exp) != STRING_CST 3348 || size >= TREE_STRING_LENGTH (exp)); 3349 return size; 3350 } 3351 3352 /* Subroutine of output_constant_def: 3353 No constant equal to EXP is known to have been output. 3354 Make a constant descriptor to enter EXP in the hash table. 3355 Assign the label number and construct RTL to refer to the 3356 constant's location in memory. 3357 Caller is responsible for updating the hash table. */ 3358 3359 static struct constant_descriptor_tree * 3360 build_constant_desc (tree exp) 3361 { 3362 struct constant_descriptor_tree *desc; 3363 rtx symbol, rtl; 3364 char label[256]; 3365 int labelno; 3366 tree decl; 3367 3368 desc = ggc_alloc<constant_descriptor_tree> (); 3369 desc->value = exp; 3370 3371 /* Create a string containing the label name, in LABEL. */ 3372 labelno = const_labelno++; 3373 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno); 3374 3375 /* Construct the VAR_DECL associated with the constant. */ 3376 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label), 3377 TREE_TYPE (exp)); 3378 DECL_ARTIFICIAL (decl) = 1; 3379 DECL_IGNORED_P (decl) = 1; 3380 TREE_READONLY (decl) = 1; 3381 TREE_STATIC (decl) = 1; 3382 TREE_ADDRESSABLE (decl) = 1; 3383 /* We don't set the RTL yet as this would cause varpool to assume that the 3384 variable is referenced. Moreover, it would just be dropped in LTO mode. 3385 Instead we set the flag that will be recognized in make_decl_rtl. */ 3386 DECL_IN_CONSTANT_POOL (decl) = 1; 3387 DECL_INITIAL (decl) = desc->value; 3388 /* ??? targetm.constant_alignment hasn't been updated for vector types on 3389 most architectures so use DATA_ALIGNMENT as well, except for strings. */ 3390 if (TREE_CODE (exp) == STRING_CST) 3391 SET_DECL_ALIGN (decl, targetm.constant_alignment (exp, DECL_ALIGN (decl))); 3392 else 3393 align_variable (decl, 0); 3394 3395 /* Now construct the SYMBOL_REF and the MEM. */ 3396 if (use_object_blocks_p ()) 3397 { 3398 int align = (TREE_CODE (decl) == CONST_DECL 3399 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl)) 3400 ? DECL_ALIGN (decl) 3401 : symtab_node::get (decl)->definition_alignment ()); 3402 section *sect = get_constant_section (exp, align); 3403 symbol = create_block_symbol (ggc_strdup (label), 3404 get_block_for_section (sect), -1); 3405 } 3406 else 3407 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label)); 3408 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL; 3409 SET_SYMBOL_REF_DECL (symbol, decl); 3410 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1; 3411 3412 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol); 3413 set_mem_attributes (rtl, exp, 1); 3414 set_mem_alias_set (rtl, 0); 3415 3416 /* Putting EXP into the literal pool might have imposed a different 3417 alignment which should be visible in the RTX as well. */ 3418 set_mem_align (rtl, DECL_ALIGN (decl)); 3419 3420 /* We cannot share RTX'es in pool entries. 3421 Mark this piece of RTL as required for unsharing. */ 3422 RTX_FLAG (rtl, used) = 1; 3423 3424 /* Set flags or add text to the name to record information, such as 3425 that it is a local symbol. If the name is changed, the macro 3426 ASM_OUTPUT_LABELREF will have to know how to strip this 3427 information. This call might invalidate our local variable 3428 SYMBOL; we can't use it afterward. */ 3429 targetm.encode_section_info (exp, rtl, true); 3430 3431 desc->rtl = rtl; 3432 3433 return desc; 3434 } 3435 3436 /* Subroutine of output_constant_def and tree_output_constant_def: 3437 Add a constant to the hash table that tracks which constants 3438 already have labels. */ 3439 3440 static constant_descriptor_tree * 3441 add_constant_to_table (tree exp) 3442 { 3443 /* The hash table methods may call output_constant_def for addressed 3444 constants, so handle them first. */ 3445 output_addressed_constants (exp); 3446 3447 /* Sanity check to catch recursive insertion. */ 3448 static bool inserting; 3449 gcc_assert (!inserting); 3450 inserting = true; 3451 3452 /* Look up EXP in the table of constant descriptors. If we didn't 3453 find it, create a new one. */ 3454 struct constant_descriptor_tree key; 3455 key.value = exp; 3456 key.hash = const_hash_1 (exp); 3457 constant_descriptor_tree **loc 3458 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT); 3459 3460 inserting = false; 3461 3462 struct constant_descriptor_tree *desc = *loc; 3463 if (!desc) 3464 { 3465 desc = build_constant_desc (exp); 3466 desc->hash = key.hash; 3467 *loc = desc; 3468 } 3469 3470 return desc; 3471 } 3472 3473 /* Return an rtx representing a reference to constant data in memory 3474 for the constant expression EXP. 3475 3476 If assembler code for such a constant has already been output, 3477 return an rtx to refer to it. 3478 Otherwise, output such a constant in memory 3479 and generate an rtx for it. 3480 3481 If DEFER is nonzero, this constant can be deferred and output only 3482 if referenced in the function after all optimizations. 3483 3484 `const_desc_table' records which constants already have label strings. */ 3485 3486 rtx 3487 output_constant_def (tree exp, int defer) 3488 { 3489 struct constant_descriptor_tree *desc = add_constant_to_table (exp); 3490 maybe_output_constant_def_contents (desc, defer); 3491 return desc->rtl; 3492 } 3493 3494 /* Subroutine of output_constant_def: Decide whether or not we need to 3495 output the constant DESC now, and if so, do it. */ 3496 static void 3497 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc, 3498 int defer) 3499 { 3500 rtx symbol = XEXP (desc->rtl, 0); 3501 tree exp = desc->value; 3502 3503 if (flag_syntax_only) 3504 return; 3505 3506 if (TREE_ASM_WRITTEN (exp)) 3507 /* Already output; don't do it again. */ 3508 return; 3509 3510 /* We can always defer constants as long as the context allows 3511 doing so. */ 3512 if (defer) 3513 { 3514 /* Increment n_deferred_constants if it exists. It needs to be at 3515 least as large as the number of constants actually referred to 3516 by the function. If it's too small we'll stop looking too early 3517 and fail to emit constants; if it's too large we'll only look 3518 through the entire function when we could have stopped earlier. */ 3519 if (cfun) 3520 n_deferred_constants++; 3521 return; 3522 } 3523 3524 output_constant_def_contents (symbol); 3525 } 3526 3527 /* Subroutine of output_constant_def_contents. Output the definition 3528 of constant EXP, which is pointed to by label LABEL. ALIGN is the 3529 constant's alignment in bits. */ 3530 3531 static void 3532 assemble_constant_contents (tree exp, const char *label, unsigned int align, 3533 bool merge_strings) 3534 { 3535 HOST_WIDE_INT size; 3536 3537 size = get_constant_size (exp); 3538 3539 /* Do any machine/system dependent processing of the constant. */ 3540 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size); 3541 3542 /* Output the value of EXP. */ 3543 output_constant (exp, size, align, false, merge_strings); 3544 3545 targetm.asm_out.decl_end (); 3546 } 3547 3548 /* We must output the constant data referred to by SYMBOL; do so. */ 3549 3550 static void 3551 output_constant_def_contents (rtx symbol) 3552 { 3553 tree decl = SYMBOL_REF_DECL (symbol); 3554 tree exp = DECL_INITIAL (decl); 3555 bool asan_protected = false; 3556 3557 /* Make sure any other constants whose addresses appear in EXP 3558 are assigned label numbers. */ 3559 output_addressed_constants (exp); 3560 3561 /* We are no longer deferring this constant. */ 3562 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1; 3563 3564 if ((flag_sanitize & SANITIZE_ADDRESS) 3565 && TREE_CODE (exp) == STRING_CST 3566 && asan_protect_global (exp)) 3567 { 3568 asan_protected = true; 3569 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl), 3570 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT)); 3571 } 3572 3573 /* If the constant is part of an object block, make sure that the 3574 decl has been positioned within its block, but do not write out 3575 its definition yet. output_object_blocks will do that later. */ 3576 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol)) 3577 place_block_symbol (symbol); 3578 else 3579 { 3580 int align = (TREE_CODE (decl) == CONST_DECL 3581 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl)) 3582 ? DECL_ALIGN (decl) 3583 : symtab_node::get (decl)->definition_alignment ()); 3584 section *sect = get_constant_section (exp, align); 3585 switch_to_section (sect); 3586 if (align > BITS_PER_UNIT) 3587 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 3588 assemble_constant_contents (exp, XSTR (symbol, 0), align, 3589 (sect->common.flags & SECTION_MERGE) 3590 && (sect->common.flags & SECTION_STRINGS)); 3591 if (asan_protected) 3592 { 3593 HOST_WIDE_INT size = get_constant_size (exp); 3594 assemble_zeros (asan_red_zone_size (size)); 3595 } 3596 } 3597 } 3598 3599 /* Look up EXP in the table of constant descriptors. Return the rtl 3600 if it has been emitted, else null. */ 3601 3602 rtx 3603 lookup_constant_def (tree exp) 3604 { 3605 struct constant_descriptor_tree key; 3606 3607 key.value = exp; 3608 key.hash = const_hash_1 (exp); 3609 constant_descriptor_tree *desc 3610 = const_desc_htab->find_with_hash (&key, key.hash); 3611 3612 return (desc ? desc->rtl : NULL_RTX); 3613 } 3614 3615 /* Return a tree representing a reference to constant data in memory 3616 for the constant expression EXP. 3617 3618 This is the counterpart of output_constant_def at the Tree level. */ 3619 3620 tree 3621 tree_output_constant_def (tree exp) 3622 { 3623 struct constant_descriptor_tree *desc = add_constant_to_table (exp); 3624 tree decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0)); 3625 varpool_node::finalize_decl (decl); 3626 return decl; 3627 } 3628 3629 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx { 3630 struct constant_descriptor_rtx *next; 3631 rtx mem; 3632 rtx sym; 3633 rtx constant; 3634 HOST_WIDE_INT offset; 3635 hashval_t hash; 3636 fixed_size_mode mode; 3637 unsigned int align; 3638 int labelno; 3639 int mark; 3640 }; 3641 3642 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx> 3643 { 3644 static hashval_t hash (constant_descriptor_rtx *); 3645 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *); 3646 }; 3647 3648 /* Used in the hash tables to avoid outputting the same constant 3649 twice. Unlike 'struct constant_descriptor_tree', RTX constants 3650 are output once per function, not once per file. */ 3651 /* ??? Only a few targets need per-function constant pools. Most 3652 can use one per-file pool. Should add a targetm bit to tell the 3653 difference. */ 3654 3655 struct GTY(()) rtx_constant_pool { 3656 /* Pointers to first and last constant in pool, as ordered by offset. */ 3657 struct constant_descriptor_rtx *first; 3658 struct constant_descriptor_rtx *last; 3659 3660 /* Hash facility for making memory-constants from constant rtl-expressions. 3661 It is used on RISC machines where immediate integer arguments and 3662 constant addresses are restricted so that such constants must be stored 3663 in memory. */ 3664 hash_table<const_rtx_desc_hasher> *const_rtx_htab; 3665 3666 /* Current offset in constant pool (does not include any 3667 machine-specific header). */ 3668 HOST_WIDE_INT offset; 3669 }; 3670 3671 /* Hash and compare functions for const_rtx_htab. */ 3672 3673 hashval_t 3674 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc) 3675 { 3676 return desc->hash; 3677 } 3678 3679 bool 3680 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x, 3681 constant_descriptor_rtx *y) 3682 { 3683 if (x->mode != y->mode) 3684 return 0; 3685 return rtx_equal_p (x->constant, y->constant); 3686 } 3687 3688 /* Hash one component of a constant. */ 3689 3690 static hashval_t 3691 const_rtx_hash_1 (const_rtx x) 3692 { 3693 unsigned HOST_WIDE_INT hwi; 3694 machine_mode mode; 3695 enum rtx_code code; 3696 hashval_t h; 3697 int i; 3698 3699 code = GET_CODE (x); 3700 mode = GET_MODE (x); 3701 h = (hashval_t) code * 1048573 + mode; 3702 3703 switch (code) 3704 { 3705 case CONST_INT: 3706 hwi = INTVAL (x); 3707 3708 fold_hwi: 3709 { 3710 int shift = sizeof (hashval_t) * CHAR_BIT; 3711 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t); 3712 3713 h ^= (hashval_t) hwi; 3714 for (i = 1; i < n; ++i) 3715 { 3716 hwi >>= shift; 3717 h ^= (hashval_t) hwi; 3718 } 3719 } 3720 break; 3721 3722 case CONST_WIDE_INT: 3723 hwi = 0; 3724 { 3725 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++) 3726 hwi ^= CONST_WIDE_INT_ELT (x, i); 3727 goto fold_hwi; 3728 } 3729 3730 case CONST_DOUBLE: 3731 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode) 3732 { 3733 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x); 3734 goto fold_hwi; 3735 } 3736 else 3737 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x)); 3738 break; 3739 3740 case CONST_FIXED: 3741 h ^= fixed_hash (CONST_FIXED_VALUE (x)); 3742 break; 3743 3744 case SYMBOL_REF: 3745 h ^= htab_hash_string (XSTR (x, 0)); 3746 break; 3747 3748 case LABEL_REF: 3749 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x)); 3750 break; 3751 3752 case UNSPEC: 3753 case UNSPEC_VOLATILE: 3754 h = h * 251 + XINT (x, 1); 3755 break; 3756 3757 default: 3758 break; 3759 } 3760 3761 return h; 3762 } 3763 3764 /* Compute a hash value for X, which should be a constant. */ 3765 3766 static hashval_t 3767 const_rtx_hash (rtx x) 3768 { 3769 hashval_t h = 0; 3770 subrtx_iterator::array_type array; 3771 FOR_EACH_SUBRTX (iter, array, x, ALL) 3772 h = h * 509 + const_rtx_hash_1 (*iter); 3773 return h; 3774 } 3775 3776 3777 /* Create and return a new rtx constant pool. */ 3778 3779 static struct rtx_constant_pool * 3780 create_constant_pool (void) 3781 { 3782 struct rtx_constant_pool *pool; 3783 3784 pool = ggc_alloc<rtx_constant_pool> (); 3785 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31); 3786 pool->first = NULL; 3787 pool->last = NULL; 3788 pool->offset = 0; 3789 return pool; 3790 } 3791 3792 /* Initialize constant pool hashing for a new function. */ 3793 3794 void 3795 init_varasm_status (void) 3796 { 3797 crtl->varasm.pool = create_constant_pool (); 3798 crtl->varasm.deferred_constants = 0; 3799 } 3800 3801 /* Given a MINUS expression, simplify it if both sides 3802 include the same symbol. */ 3803 3804 rtx 3805 simplify_subtraction (rtx x) 3806 { 3807 rtx r = simplify_rtx (x); 3808 return r ? r : x; 3809 } 3810 3811 /* Given a constant rtx X, make (or find) a memory constant for its value 3812 and return a MEM rtx to refer to it in memory. IN_MODE is the mode 3813 of X. */ 3814 3815 rtx 3816 force_const_mem (machine_mode in_mode, rtx x) 3817 { 3818 struct constant_descriptor_rtx *desc, tmp; 3819 struct rtx_constant_pool *pool; 3820 char label[256]; 3821 rtx def, symbol; 3822 hashval_t hash; 3823 unsigned int align; 3824 constant_descriptor_rtx **slot; 3825 fixed_size_mode mode; 3826 3827 /* We can't force variable-sized objects to memory. */ 3828 if (!is_a <fixed_size_mode> (in_mode, &mode)) 3829 return NULL_RTX; 3830 3831 /* If we're not allowed to drop X into the constant pool, don't. */ 3832 if (targetm.cannot_force_const_mem (mode, x)) 3833 return NULL_RTX; 3834 3835 /* Record that this function has used a constant pool entry. */ 3836 crtl->uses_const_pool = 1; 3837 3838 /* Decide which pool to use. */ 3839 pool = (targetm.use_blocks_for_constant_p (mode, x) 3840 ? shared_constant_pool 3841 : crtl->varasm.pool); 3842 3843 /* Lookup the value in the hashtable. */ 3844 tmp.constant = x; 3845 tmp.mode = mode; 3846 hash = const_rtx_hash (x); 3847 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT); 3848 desc = *slot; 3849 3850 /* If the constant was already present, return its memory. */ 3851 if (desc) 3852 return copy_rtx (desc->mem); 3853 3854 /* Otherwise, create a new descriptor. */ 3855 desc = ggc_alloc<constant_descriptor_rtx> (); 3856 *slot = desc; 3857 3858 /* Align the location counter as required by EXP's data type. */ 3859 machine_mode align_mode = (mode == VOIDmode ? word_mode : mode); 3860 align = targetm.static_rtx_alignment (align_mode); 3861 3862 pool->offset += (align / BITS_PER_UNIT) - 1; 3863 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1); 3864 3865 desc->next = NULL; 3866 desc->constant = copy_rtx (tmp.constant); 3867 desc->offset = pool->offset; 3868 desc->hash = hash; 3869 desc->mode = mode; 3870 desc->align = align; 3871 desc->labelno = const_labelno; 3872 desc->mark = 0; 3873 3874 pool->offset += GET_MODE_SIZE (mode); 3875 if (pool->last) 3876 pool->last->next = desc; 3877 else 3878 pool->first = pool->last = desc; 3879 pool->last = desc; 3880 3881 /* Create a string containing the label name, in LABEL. */ 3882 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 3883 ++const_labelno; 3884 3885 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to 3886 the constants pool. */ 3887 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x)) 3888 { 3889 section *sect = targetm.asm_out.select_rtx_section (mode, x, align); 3890 symbol = create_block_symbol (ggc_strdup (label), 3891 get_block_for_section (sect), -1); 3892 } 3893 else 3894 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label)); 3895 desc->sym = symbol; 3896 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL; 3897 CONSTANT_POOL_ADDRESS_P (symbol) = 1; 3898 SET_SYMBOL_REF_CONSTANT (symbol, desc); 3899 3900 /* Construct the MEM. */ 3901 desc->mem = def = gen_const_mem (mode, symbol); 3902 set_mem_align (def, align); 3903 3904 /* If we're dropping a label to the constant pool, make sure we 3905 don't delete it. */ 3906 if (GET_CODE (x) == LABEL_REF) 3907 LABEL_PRESERVE_P (XEXP (x, 0)) = 1; 3908 3909 return copy_rtx (def); 3910 } 3911 3912 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */ 3913 3914 rtx 3915 get_pool_constant (const_rtx addr) 3916 { 3917 return SYMBOL_REF_CONSTANT (addr)->constant; 3918 } 3919 3920 /* Given a constant pool SYMBOL_REF, return the corresponding constant 3921 and whether it has been output or not. */ 3922 3923 rtx 3924 get_pool_constant_mark (rtx addr, bool *pmarked) 3925 { 3926 struct constant_descriptor_rtx *desc; 3927 3928 desc = SYMBOL_REF_CONSTANT (addr); 3929 *pmarked = (desc->mark != 0); 3930 return desc->constant; 3931 } 3932 3933 /* Similar, return the mode. */ 3934 3935 fixed_size_mode 3936 get_pool_mode (const_rtx addr) 3937 { 3938 return SYMBOL_REF_CONSTANT (addr)->mode; 3939 } 3940 3941 /* Return TRUE if and only if the constant pool has no entries. Note 3942 that even entries we might end up choosing not to emit are counted 3943 here, so there is the potential for missed optimizations. */ 3944 3945 bool 3946 constant_pool_empty_p (void) 3947 { 3948 return crtl->varasm.pool->first == NULL; 3949 } 3950 3951 /* Worker function for output_constant_pool_1. Emit assembly for X 3952 in MODE with known alignment ALIGN. */ 3953 3954 static void 3955 output_constant_pool_2 (fixed_size_mode mode, rtx x, unsigned int align) 3956 { 3957 switch (GET_MODE_CLASS (mode)) 3958 { 3959 case MODE_FLOAT: 3960 case MODE_DECIMAL_FLOAT: 3961 { 3962 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x)); 3963 assemble_real (*CONST_DOUBLE_REAL_VALUE (x), 3964 as_a <scalar_float_mode> (mode), align, false); 3965 break; 3966 } 3967 3968 case MODE_INT: 3969 case MODE_PARTIAL_INT: 3970 case MODE_FRACT: 3971 case MODE_UFRACT: 3972 case MODE_ACCUM: 3973 case MODE_UACCUM: 3974 assemble_integer (x, GET_MODE_SIZE (mode), align, 1); 3975 break; 3976 3977 case MODE_VECTOR_BOOL: 3978 { 3979 gcc_assert (GET_CODE (x) == CONST_VECTOR); 3980 3981 /* Pick the smallest integer mode that contains at least one 3982 whole element. Often this is byte_mode and contains more 3983 than one element. */ 3984 unsigned int nelts = GET_MODE_NUNITS (mode); 3985 unsigned int elt_bits = GET_MODE_BITSIZE (mode) / nelts; 3986 unsigned int int_bits = MAX (elt_bits, BITS_PER_UNIT); 3987 scalar_int_mode int_mode = int_mode_for_size (int_bits, 0).require (); 3988 3989 /* Build the constant up one integer at a time. */ 3990 unsigned int elts_per_int = int_bits / elt_bits; 3991 for (unsigned int i = 0; i < nelts; i += elts_per_int) 3992 { 3993 unsigned HOST_WIDE_INT value = 0; 3994 unsigned int limit = MIN (nelts - i, elts_per_int); 3995 for (unsigned int j = 0; j < limit; ++j) 3996 if (INTVAL (CONST_VECTOR_ELT (x, i + j)) != 0) 3997 value |= 1 << (j * elt_bits); 3998 output_constant_pool_2 (int_mode, gen_int_mode (value, int_mode), 3999 i != 0 ? MIN (align, int_bits) : align); 4000 } 4001 break; 4002 } 4003 case MODE_VECTOR_FLOAT: 4004 case MODE_VECTOR_INT: 4005 case MODE_VECTOR_FRACT: 4006 case MODE_VECTOR_UFRACT: 4007 case MODE_VECTOR_ACCUM: 4008 case MODE_VECTOR_UACCUM: 4009 { 4010 int i, units; 4011 scalar_mode submode = GET_MODE_INNER (mode); 4012 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode)); 4013 4014 gcc_assert (GET_CODE (x) == CONST_VECTOR); 4015 units = GET_MODE_NUNITS (mode); 4016 4017 for (i = 0; i < units; i++) 4018 { 4019 rtx elt = CONST_VECTOR_ELT (x, i); 4020 output_constant_pool_2 (submode, elt, i ? subalign : align); 4021 } 4022 } 4023 break; 4024 4025 default: 4026 gcc_unreachable (); 4027 } 4028 } 4029 4030 /* Worker function for output_constant_pool. Emit constant DESC, 4031 giving it ALIGN bits of alignment. */ 4032 4033 static void 4034 output_constant_pool_1 (struct constant_descriptor_rtx *desc, 4035 unsigned int align) 4036 { 4037 rtx x, tmp; 4038 4039 x = desc->constant; 4040 4041 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF) 4042 whose CODE_LABEL has been deleted. This can occur if a jump table 4043 is eliminated by optimization. If so, write a constant of zero 4044 instead. Note that this can also happen by turning the 4045 CODE_LABEL into a NOTE. */ 4046 /* ??? This seems completely and utterly wrong. Certainly it's 4047 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper 4048 functioning even with rtx_insn::deleted and friends. */ 4049 4050 tmp = x; 4051 switch (GET_CODE (tmp)) 4052 { 4053 case CONST: 4054 if (GET_CODE (XEXP (tmp, 0)) != PLUS 4055 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF) 4056 break; 4057 tmp = XEXP (XEXP (tmp, 0), 0); 4058 /* FALLTHRU */ 4059 4060 case LABEL_REF: 4061 { 4062 rtx_insn *insn = label_ref_label (tmp); 4063 gcc_assert (!insn->deleted ()); 4064 gcc_assert (!NOTE_P (insn) 4065 || NOTE_KIND (insn) != NOTE_INSN_DELETED); 4066 break; 4067 } 4068 4069 default: 4070 break; 4071 } 4072 4073 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 4074 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode, 4075 align, desc->labelno, done); 4076 #endif 4077 4078 assemble_align (align); 4079 4080 /* Output the label. */ 4081 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno); 4082 4083 /* Output the data. 4084 Pass actual alignment value while emitting string constant to asm code 4085 as function 'output_constant_pool_1' explicitly passes the alignment as 1 4086 assuming that the data is already aligned which prevents the generation 4087 of fix-up table entries. */ 4088 output_constant_pool_2 (desc->mode, x, desc->align); 4089 4090 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS 4091 sections have proper size. */ 4092 if (align > GET_MODE_BITSIZE (desc->mode) 4093 && in_section 4094 && (in_section->common.flags & SECTION_MERGE)) 4095 assemble_align (align); 4096 4097 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 4098 done: 4099 #endif 4100 return; 4101 } 4102 4103 /* Recompute the offsets of entries in POOL, and the overall size of 4104 POOL. Do this after calling mark_constant_pool to ensure that we 4105 are computing the offset values for the pool which we will actually 4106 emit. */ 4107 4108 static void 4109 recompute_pool_offsets (struct rtx_constant_pool *pool) 4110 { 4111 struct constant_descriptor_rtx *desc; 4112 pool->offset = 0; 4113 4114 for (desc = pool->first; desc ; desc = desc->next) 4115 if (desc->mark) 4116 { 4117 /* Recalculate offset. */ 4118 unsigned int align = desc->align; 4119 pool->offset += (align / BITS_PER_UNIT) - 1; 4120 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1); 4121 desc->offset = pool->offset; 4122 pool->offset += GET_MODE_SIZE (desc->mode); 4123 } 4124 } 4125 4126 /* Mark all constants that are referenced by SYMBOL_REFs in X. 4127 Emit referenced deferred strings. */ 4128 4129 static void 4130 mark_constants_in_pattern (rtx insn) 4131 { 4132 subrtx_iterator::array_type array; 4133 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL) 4134 { 4135 const_rtx x = *iter; 4136 if (GET_CODE (x) == SYMBOL_REF) 4137 { 4138 if (CONSTANT_POOL_ADDRESS_P (x)) 4139 { 4140 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x); 4141 if (desc->mark == 0) 4142 { 4143 desc->mark = 1; 4144 iter.substitute (desc->constant); 4145 } 4146 } 4147 else if (TREE_CONSTANT_POOL_ADDRESS_P (x)) 4148 { 4149 tree decl = SYMBOL_REF_DECL (x); 4150 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl))) 4151 { 4152 n_deferred_constants--; 4153 output_constant_def_contents (CONST_CAST_RTX (x)); 4154 } 4155 } 4156 } 4157 } 4158 } 4159 4160 /* Look through appropriate parts of INSN, marking all entries in the 4161 constant pool which are actually being used. Entries that are only 4162 referenced by other constants are also marked as used. Emit 4163 deferred strings that are used. */ 4164 4165 static void 4166 mark_constants (rtx_insn *insn) 4167 { 4168 if (!INSN_P (insn)) 4169 return; 4170 4171 /* Insns may appear inside a SEQUENCE. Only check the patterns of 4172 insns, not any notes that may be attached. We don't want to mark 4173 a constant just because it happens to appear in a REG_EQUIV note. */ 4174 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn))) 4175 { 4176 int i, n = seq->len (); 4177 for (i = 0; i < n; ++i) 4178 { 4179 rtx subinsn = seq->element (i); 4180 if (INSN_P (subinsn)) 4181 mark_constants_in_pattern (subinsn); 4182 } 4183 } 4184 else 4185 mark_constants_in_pattern (insn); 4186 } 4187 4188 /* Look through the instructions for this function, and mark all the 4189 entries in POOL which are actually being used. Emit deferred constants 4190 which have indeed been used. */ 4191 4192 static void 4193 mark_constant_pool (void) 4194 { 4195 rtx_insn *insn; 4196 4197 if (!crtl->uses_const_pool && n_deferred_constants == 0) 4198 return; 4199 4200 for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) 4201 mark_constants (insn); 4202 } 4203 4204 /* Write all the constants in POOL. */ 4205 4206 static void 4207 output_constant_pool_contents (struct rtx_constant_pool *pool) 4208 { 4209 struct constant_descriptor_rtx *desc; 4210 4211 for (desc = pool->first; desc ; desc = desc->next) 4212 if (desc->mark) 4213 { 4214 /* If the constant is part of an object_block, make sure that 4215 the constant has been positioned within its block, but do not 4216 write out its definition yet. output_object_blocks will do 4217 that later. */ 4218 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym) 4219 && SYMBOL_REF_BLOCK (desc->sym)) 4220 place_block_symbol (desc->sym); 4221 else 4222 { 4223 switch_to_section (targetm.asm_out.select_rtx_section 4224 (desc->mode, desc->constant, desc->align)); 4225 output_constant_pool_1 (desc, desc->align); 4226 } 4227 } 4228 } 4229 4230 /* Mark all constants that are used in the current function, then write 4231 out the function's private constant pool. */ 4232 4233 static void 4234 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED, 4235 tree fndecl ATTRIBUTE_UNUSED) 4236 { 4237 struct rtx_constant_pool *pool = crtl->varasm.pool; 4238 4239 /* It is possible for gcc to call force_const_mem and then to later 4240 discard the instructions which refer to the constant. In such a 4241 case we do not need to output the constant. */ 4242 mark_constant_pool (); 4243 4244 /* Having marked the constant pool entries we'll actually emit, we 4245 now need to rebuild the offset information, which may have become 4246 stale. */ 4247 recompute_pool_offsets (pool); 4248 4249 #ifdef ASM_OUTPUT_POOL_PROLOGUE 4250 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset); 4251 #endif 4252 4253 output_constant_pool_contents (pool); 4254 4255 #ifdef ASM_OUTPUT_POOL_EPILOGUE 4256 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset); 4257 #endif 4258 } 4259 4260 /* Write the contents of the shared constant pool. */ 4261 4262 void 4263 output_shared_constant_pool (void) 4264 { 4265 output_constant_pool_contents (shared_constant_pool); 4266 } 4267 4268 /* Determine what kind of relocations EXP may need. */ 4269 4270 int 4271 compute_reloc_for_constant (tree exp) 4272 { 4273 int reloc = 0, reloc2; 4274 tree tem; 4275 4276 switch (TREE_CODE (exp)) 4277 { 4278 case ADDR_EXPR: 4279 case FDESC_EXPR: 4280 /* Go inside any operations that get_inner_reference can handle and see 4281 if what's inside is a constant: no need to do anything here for 4282 addresses of variables or functions. */ 4283 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem); 4284 tem = TREE_OPERAND (tem, 0)) 4285 ; 4286 4287 if (TREE_CODE (tem) == MEM_REF 4288 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR) 4289 { 4290 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0)); 4291 break; 4292 } 4293 4294 if (!targetm.binds_local_p (tem)) 4295 reloc |= 2; 4296 else 4297 reloc |= 1; 4298 break; 4299 4300 case PLUS_EXPR: 4301 case POINTER_PLUS_EXPR: 4302 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0)); 4303 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1)); 4304 break; 4305 4306 case MINUS_EXPR: 4307 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0)); 4308 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1)); 4309 /* The difference of two local labels is computable at link time. */ 4310 if (reloc == 1 && reloc2 == 1) 4311 reloc = 0; 4312 else 4313 reloc |= reloc2; 4314 break; 4315 4316 CASE_CONVERT: 4317 case VIEW_CONVERT_EXPR: 4318 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0)); 4319 break; 4320 4321 case CONSTRUCTOR: 4322 { 4323 unsigned HOST_WIDE_INT idx; 4324 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem) 4325 if (tem != 0) 4326 reloc |= compute_reloc_for_constant (tem); 4327 } 4328 break; 4329 4330 default: 4331 break; 4332 } 4333 return reloc; 4334 } 4335 4336 /* Find all the constants whose addresses are referenced inside of EXP, 4337 and make sure assembler code with a label has been output for each one. 4338 Indicate whether an ADDR_EXPR has been encountered. */ 4339 4340 static void 4341 output_addressed_constants (tree exp) 4342 { 4343 tree tem; 4344 4345 switch (TREE_CODE (exp)) 4346 { 4347 case ADDR_EXPR: 4348 case FDESC_EXPR: 4349 /* Go inside any operations that get_inner_reference can handle and see 4350 if what's inside is a constant: no need to do anything here for 4351 addresses of variables or functions. */ 4352 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem); 4353 tem = TREE_OPERAND (tem, 0)) 4354 ; 4355 4356 /* If we have an initialized CONST_DECL, retrieve the initializer. */ 4357 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem)) 4358 tem = DECL_INITIAL (tem); 4359 4360 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR) 4361 output_constant_def (tem, 0); 4362 4363 if (TREE_CODE (tem) == MEM_REF) 4364 output_addressed_constants (TREE_OPERAND (tem, 0)); 4365 break; 4366 4367 case PLUS_EXPR: 4368 case POINTER_PLUS_EXPR: 4369 case MINUS_EXPR: 4370 output_addressed_constants (TREE_OPERAND (exp, 1)); 4371 gcc_fallthrough (); 4372 4373 CASE_CONVERT: 4374 case VIEW_CONVERT_EXPR: 4375 output_addressed_constants (TREE_OPERAND (exp, 0)); 4376 break; 4377 4378 case CONSTRUCTOR: 4379 { 4380 unsigned HOST_WIDE_INT idx; 4381 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem) 4382 if (tem != 0) 4383 output_addressed_constants (tem); 4384 } 4385 break; 4386 4387 default: 4388 break; 4389 } 4390 } 4391 4392 /* Whether a constructor CTOR is a valid static constant initializer if all 4393 its elements are. This used to be internal to initializer_constant_valid_p 4394 and has been exposed to let other functions like categorize_ctor_elements 4395 evaluate the property while walking a constructor for other purposes. */ 4396 4397 bool 4398 constructor_static_from_elts_p (const_tree ctor) 4399 { 4400 return (TREE_CONSTANT (ctor) 4401 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE 4402 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE 4403 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE)); 4404 } 4405 4406 static tree initializer_constant_valid_p_1 (tree value, tree endtype, 4407 tree *cache); 4408 4409 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR, 4410 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE 4411 which are valid when ENDTYPE is an integer of any size; in 4412 particular, this does not accept a pointer minus a constant. This 4413 returns null_pointer_node if the VALUE is an absolute constant 4414 which can be used to initialize a static variable. Otherwise it 4415 returns NULL. */ 4416 4417 static tree 4418 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache) 4419 { 4420 tree op0, op1; 4421 4422 if (!INTEGRAL_TYPE_P (endtype)) 4423 return NULL_TREE; 4424 4425 op0 = TREE_OPERAND (value, 0); 4426 op1 = TREE_OPERAND (value, 1); 4427 4428 /* Like STRIP_NOPS except allow the operand mode to widen. This 4429 works around a feature of fold that simplifies (int)(p1 - p2) to 4430 ((int)p1 - (int)p2) under the theory that the narrower operation 4431 is cheaper. */ 4432 4433 while (CONVERT_EXPR_P (op0) 4434 || TREE_CODE (op0) == NON_LVALUE_EXPR) 4435 { 4436 tree inner = TREE_OPERAND (op0, 0); 4437 if (inner == error_mark_node 4438 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner))) 4439 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op0))) 4440 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner))))) 4441 break; 4442 op0 = inner; 4443 } 4444 4445 while (CONVERT_EXPR_P (op1) 4446 || TREE_CODE (op1) == NON_LVALUE_EXPR) 4447 { 4448 tree inner = TREE_OPERAND (op1, 0); 4449 if (inner == error_mark_node 4450 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner))) 4451 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op1))) 4452 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner))))) 4453 break; 4454 op1 = inner; 4455 } 4456 4457 op0 = initializer_constant_valid_p_1 (op0, endtype, cache); 4458 if (!op0) 4459 return NULL_TREE; 4460 4461 op1 = initializer_constant_valid_p_1 (op1, endtype, 4462 cache ? cache + 2 : NULL); 4463 /* Both initializers must be known. */ 4464 if (op1) 4465 { 4466 if (op0 == op1 4467 && (op0 == null_pointer_node 4468 || TREE_CODE (value) == MINUS_EXPR)) 4469 return null_pointer_node; 4470 4471 /* Support differences between labels. */ 4472 if (TREE_CODE (op0) == LABEL_DECL 4473 && TREE_CODE (op1) == LABEL_DECL) 4474 return null_pointer_node; 4475 4476 if (TREE_CODE (op0) == STRING_CST 4477 && TREE_CODE (op1) == STRING_CST 4478 && operand_equal_p (op0, op1, 1)) 4479 return null_pointer_node; 4480 } 4481 4482 return NULL_TREE; 4483 } 4484 4485 /* Helper function of initializer_constant_valid_p. 4486 Return nonzero if VALUE is a valid constant-valued expression 4487 for use in initializing a static variable; one that can be an 4488 element of a "constant" initializer. 4489 4490 Return null_pointer_node if the value is absolute; 4491 if it is relocatable, return the variable that determines the relocation. 4492 We assume that VALUE has been folded as much as possible; 4493 therefore, we do not need to check for such things as 4494 arithmetic-combinations of integers. 4495 4496 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */ 4497 4498 static tree 4499 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache) 4500 { 4501 tree ret; 4502 4503 switch (TREE_CODE (value)) 4504 { 4505 case CONSTRUCTOR: 4506 if (constructor_static_from_elts_p (value)) 4507 { 4508 unsigned HOST_WIDE_INT idx; 4509 tree elt; 4510 bool absolute = true; 4511 4512 if (cache && cache[0] == value) 4513 return cache[1]; 4514 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt) 4515 { 4516 tree reloc; 4517 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt), 4518 NULL); 4519 if (!reloc 4520 /* An absolute value is required with reverse SSO. */ 4521 || (reloc != null_pointer_node 4522 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value)) 4523 && !AGGREGATE_TYPE_P (TREE_TYPE (elt)))) 4524 { 4525 if (cache) 4526 { 4527 cache[0] = value; 4528 cache[1] = NULL_TREE; 4529 } 4530 return NULL_TREE; 4531 } 4532 if (reloc != null_pointer_node) 4533 absolute = false; 4534 } 4535 /* For a non-absolute relocation, there is no single 4536 variable that can be "the variable that determines the 4537 relocation." */ 4538 if (cache) 4539 { 4540 cache[0] = value; 4541 cache[1] = absolute ? null_pointer_node : error_mark_node; 4542 } 4543 return absolute ? null_pointer_node : error_mark_node; 4544 } 4545 4546 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE; 4547 4548 case INTEGER_CST: 4549 case VECTOR_CST: 4550 case REAL_CST: 4551 case FIXED_CST: 4552 case STRING_CST: 4553 case COMPLEX_CST: 4554 return null_pointer_node; 4555 4556 case ADDR_EXPR: 4557 case FDESC_EXPR: 4558 { 4559 tree op0 = staticp (TREE_OPERAND (value, 0)); 4560 if (op0) 4561 { 4562 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out 4563 to be a constant, this is old-skool offsetof-like nonsense. */ 4564 if (TREE_CODE (op0) == INDIRECT_REF 4565 && TREE_CONSTANT (TREE_OPERAND (op0, 0))) 4566 return null_pointer_node; 4567 /* Taking the address of a nested function involves a trampoline, 4568 unless we don't need or want one. */ 4569 if (TREE_CODE (op0) == FUNCTION_DECL 4570 && DECL_STATIC_CHAIN (op0) 4571 && !TREE_NO_TRAMPOLINE (value)) 4572 return NULL_TREE; 4573 /* "&{...}" requires a temporary to hold the constructed 4574 object. */ 4575 if (TREE_CODE (op0) == CONSTRUCTOR) 4576 return NULL_TREE; 4577 } 4578 return op0; 4579 } 4580 4581 case NON_LVALUE_EXPR: 4582 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0), 4583 endtype, cache); 4584 4585 case VIEW_CONVERT_EXPR: 4586 { 4587 tree src = TREE_OPERAND (value, 0); 4588 tree src_type = TREE_TYPE (src); 4589 tree dest_type = TREE_TYPE (value); 4590 4591 /* Allow view-conversions from aggregate to non-aggregate type only 4592 if the bit pattern is fully preserved afterwards; otherwise, the 4593 RTL expander won't be able to apply a subsequent transformation 4594 to the underlying constructor. */ 4595 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type)) 4596 { 4597 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type)) 4598 return initializer_constant_valid_p_1 (src, endtype, cache); 4599 else 4600 return NULL_TREE; 4601 } 4602 4603 /* Allow all other kinds of view-conversion. */ 4604 return initializer_constant_valid_p_1 (src, endtype, cache); 4605 } 4606 4607 CASE_CONVERT: 4608 { 4609 tree src = TREE_OPERAND (value, 0); 4610 tree src_type = TREE_TYPE (src); 4611 tree dest_type = TREE_TYPE (value); 4612 4613 /* Allow conversions between pointer types, floating-point 4614 types, and offset types. */ 4615 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)) 4616 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type)) 4617 || (TREE_CODE (dest_type) == OFFSET_TYPE 4618 && TREE_CODE (src_type) == OFFSET_TYPE)) 4619 return initializer_constant_valid_p_1 (src, endtype, cache); 4620 4621 /* Allow length-preserving conversions between integer types. */ 4622 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type) 4623 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type))) 4624 return initializer_constant_valid_p_1 (src, endtype, cache); 4625 4626 /* Allow conversions between other integer types only if 4627 explicit value. Don't allow sign-extension to a type larger 4628 than word and pointer, there aren't relocations that would 4629 allow to sign extend it to a wider type. */ 4630 if (INTEGRAL_TYPE_P (dest_type) 4631 && INTEGRAL_TYPE_P (src_type) 4632 && (TYPE_UNSIGNED (src_type) 4633 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type) 4634 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD 4635 || TYPE_PRECISION (dest_type) <= POINTER_SIZE)) 4636 { 4637 tree inner = initializer_constant_valid_p_1 (src, endtype, cache); 4638 if (inner == null_pointer_node) 4639 return null_pointer_node; 4640 break; 4641 } 4642 4643 /* Allow (int) &foo provided int is as wide as a pointer. */ 4644 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type) 4645 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))) 4646 return initializer_constant_valid_p_1 (src, endtype, cache); 4647 4648 /* Likewise conversions from int to pointers, but also allow 4649 conversions from 0. */ 4650 if ((POINTER_TYPE_P (dest_type) 4651 || TREE_CODE (dest_type) == OFFSET_TYPE) 4652 && INTEGRAL_TYPE_P (src_type)) 4653 { 4654 if (TREE_CODE (src) == INTEGER_CST 4655 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)) 4656 return null_pointer_node; 4657 if (integer_zerop (src)) 4658 return null_pointer_node; 4659 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)) 4660 return initializer_constant_valid_p_1 (src, endtype, cache); 4661 } 4662 4663 /* Allow conversions to struct or union types if the value 4664 inside is okay. */ 4665 if (TREE_CODE (dest_type) == RECORD_TYPE 4666 || TREE_CODE (dest_type) == UNION_TYPE) 4667 return initializer_constant_valid_p_1 (src, endtype, cache); 4668 } 4669 break; 4670 4671 case POINTER_PLUS_EXPR: 4672 case PLUS_EXPR: 4673 /* Any valid floating-point constants will have been folded by now; 4674 with -frounding-math we hit this with addition of two constants. */ 4675 if (TREE_CODE (endtype) == REAL_TYPE) 4676 return NULL_TREE; 4677 if (cache && cache[0] == value) 4678 return cache[1]; 4679 if (! INTEGRAL_TYPE_P (endtype) 4680 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value))) 4681 { 4682 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE }; 4683 tree valid0 4684 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0), 4685 endtype, ncache); 4686 tree valid1 4687 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1), 4688 endtype, ncache + 2); 4689 /* If either term is absolute, use the other term's relocation. */ 4690 if (valid0 == null_pointer_node) 4691 ret = valid1; 4692 else if (valid1 == null_pointer_node) 4693 ret = valid0; 4694 /* Support narrowing pointer differences. */ 4695 else 4696 ret = narrowing_initializer_constant_valid_p (value, endtype, 4697 ncache); 4698 } 4699 else 4700 /* Support narrowing pointer differences. */ 4701 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL); 4702 if (cache) 4703 { 4704 cache[0] = value; 4705 cache[1] = ret; 4706 } 4707 return ret; 4708 4709 case POINTER_DIFF_EXPR: 4710 case MINUS_EXPR: 4711 if (TREE_CODE (endtype) == REAL_TYPE) 4712 return NULL_TREE; 4713 if (cache && cache[0] == value) 4714 return cache[1]; 4715 if (! INTEGRAL_TYPE_P (endtype) 4716 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value))) 4717 { 4718 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE }; 4719 tree valid0 4720 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0), 4721 endtype, ncache); 4722 tree valid1 4723 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1), 4724 endtype, ncache + 2); 4725 /* Win if second argument is absolute. */ 4726 if (valid1 == null_pointer_node) 4727 ret = valid0; 4728 /* Win if both arguments have the same relocation. 4729 Then the value is absolute. */ 4730 else if (valid0 == valid1 && valid0 != 0) 4731 ret = null_pointer_node; 4732 /* Since GCC guarantees that string constants are unique in the 4733 generated code, a subtraction between two copies of the same 4734 constant string is absolute. */ 4735 else if (valid0 && TREE_CODE (valid0) == STRING_CST 4736 && valid1 && TREE_CODE (valid1) == STRING_CST 4737 && operand_equal_p (valid0, valid1, 1)) 4738 ret = null_pointer_node; 4739 /* Support narrowing differences. */ 4740 else 4741 ret = narrowing_initializer_constant_valid_p (value, endtype, 4742 ncache); 4743 } 4744 else 4745 /* Support narrowing differences. */ 4746 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL); 4747 if (cache) 4748 { 4749 cache[0] = value; 4750 cache[1] = ret; 4751 } 4752 return ret; 4753 4754 default: 4755 break; 4756 } 4757 4758 return NULL_TREE; 4759 } 4760 4761 /* Return nonzero if VALUE is a valid constant-valued expression 4762 for use in initializing a static variable; one that can be an 4763 element of a "constant" initializer. 4764 4765 Return null_pointer_node if the value is absolute; 4766 if it is relocatable, return the variable that determines the relocation. 4767 We assume that VALUE has been folded as much as possible; 4768 therefore, we do not need to check for such things as 4769 arithmetic-combinations of integers. */ 4770 tree 4771 initializer_constant_valid_p (tree value, tree endtype, bool reverse) 4772 { 4773 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL); 4774 4775 /* An absolute value is required with reverse storage order. */ 4776 if (reloc 4777 && reloc != null_pointer_node 4778 && reverse 4779 && !AGGREGATE_TYPE_P (endtype) 4780 && !VECTOR_TYPE_P (endtype)) 4781 reloc = NULL_TREE; 4782 4783 return reloc; 4784 } 4785 4786 /* Return true if VALUE is a valid constant-valued expression 4787 for use in initializing a static bit-field; one that can be 4788 an element of a "constant" initializer. */ 4789 4790 bool 4791 initializer_constant_valid_for_bitfield_p (tree value) 4792 { 4793 /* For bitfields we support integer constants or possibly nested aggregates 4794 of such. */ 4795 switch (TREE_CODE (value)) 4796 { 4797 case CONSTRUCTOR: 4798 { 4799 unsigned HOST_WIDE_INT idx; 4800 tree elt; 4801 4802 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt) 4803 if (!initializer_constant_valid_for_bitfield_p (elt)) 4804 return false; 4805 return true; 4806 } 4807 4808 case INTEGER_CST: 4809 case REAL_CST: 4810 return true; 4811 4812 case VIEW_CONVERT_EXPR: 4813 case NON_LVALUE_EXPR: 4814 return 4815 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0)); 4816 4817 default: 4818 break; 4819 } 4820 4821 return false; 4822 } 4823 4824 /* Check if a STRING_CST fits into the field. 4825 Tolerate only the case when the NUL termination 4826 does not fit into the field. */ 4827 4828 static bool 4829 check_string_literal (tree string, unsigned HOST_WIDE_INT size) 4830 { 4831 tree type = TREE_TYPE (string); 4832 tree eltype = TREE_TYPE (type); 4833 unsigned HOST_WIDE_INT elts = tree_to_uhwi (TYPE_SIZE_UNIT (eltype)); 4834 unsigned HOST_WIDE_INT mem_size = tree_to_uhwi (TYPE_SIZE_UNIT (type)); 4835 int len = TREE_STRING_LENGTH (string); 4836 4837 if (elts != 1 && elts != 2 && elts != 4) 4838 return false; 4839 if (len < 0 || len % elts != 0) 4840 return false; 4841 if (size < (unsigned)len) 4842 return false; 4843 if (mem_size != size) 4844 return false; 4845 return true; 4846 } 4847 4848 /* output_constructor outer state of relevance in recursive calls, typically 4849 for nested aggregate bitfields. */ 4850 4851 struct oc_outer_state { 4852 unsigned int bit_offset; /* current position in ... */ 4853 int byte; /* ... the outer byte buffer. */ 4854 }; 4855 4856 static unsigned HOST_WIDE_INT 4857 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool, 4858 oc_outer_state *); 4859 4860 /* Output assembler code for constant EXP, with no label. 4861 This includes the pseudo-op such as ".int" or ".byte", and a newline. 4862 Assumes output_addressed_constants has been done on EXP already. 4863 4864 Generate at least SIZE bytes of assembler data, padding at the end 4865 with zeros if necessary. SIZE must always be specified. The returned 4866 value is the actual number of bytes of assembler data generated, which 4867 may be bigger than SIZE if the object contains a variable length field. 4868 4869 SIZE is important for structure constructors, 4870 since trailing members may have been omitted from the constructor. 4871 It is also important for initialization of arrays from string constants 4872 since the full length of the string constant might not be wanted. 4873 It is also needed for initialization of unions, where the initializer's 4874 type is just one member, and that may not be as long as the union. 4875 4876 There a case in which we would fail to output exactly SIZE bytes: 4877 for a structure constructor that wants to produce more than SIZE bytes. 4878 But such constructors will never be generated for any possible input. 4879 4880 ALIGN is the alignment of the data in bits. 4881 4882 If REVERSE is true, EXP is output in reverse storage order. */ 4883 4884 static unsigned HOST_WIDE_INT 4885 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align, 4886 bool reverse, bool merge_strings) 4887 { 4888 enum tree_code code; 4889 unsigned HOST_WIDE_INT thissize; 4890 rtx cst; 4891 4892 if (size == 0 || flag_syntax_only) 4893 return size; 4894 4895 /* See if we're trying to initialize a pointer in a non-default mode 4896 to the address of some declaration somewhere. If the target says 4897 the mode is valid for pointers, assume the target has a way of 4898 resolving it. */ 4899 if (TREE_CODE (exp) == NOP_EXPR 4900 && POINTER_TYPE_P (TREE_TYPE (exp)) 4901 && targetm.addr_space.valid_pointer_mode 4902 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)), 4903 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp))))) 4904 { 4905 tree saved_type = TREE_TYPE (exp); 4906 4907 /* Peel off any intermediate conversions-to-pointer for valid 4908 pointer modes. */ 4909 while (TREE_CODE (exp) == NOP_EXPR 4910 && POINTER_TYPE_P (TREE_TYPE (exp)) 4911 && targetm.addr_space.valid_pointer_mode 4912 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)), 4913 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp))))) 4914 exp = TREE_OPERAND (exp, 0); 4915 4916 /* If what we're left with is the address of something, we can 4917 convert the address to the final type and output it that 4918 way. */ 4919 if (TREE_CODE (exp) == ADDR_EXPR) 4920 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0)); 4921 /* Likewise for constant ints. */ 4922 else if (TREE_CODE (exp) == INTEGER_CST) 4923 exp = fold_convert (saved_type, exp); 4924 4925 } 4926 4927 /* Eliminate any conversions since we'll be outputting the underlying 4928 constant. */ 4929 while (CONVERT_EXPR_P (exp) 4930 || TREE_CODE (exp) == NON_LVALUE_EXPR 4931 || TREE_CODE (exp) == VIEW_CONVERT_EXPR) 4932 { 4933 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp)); 4934 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0))); 4935 4936 /* Make sure eliminating the conversion is really a no-op, except with 4937 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and 4938 union types to allow for Ada unchecked unions. */ 4939 if (type_size > op_size 4940 && TREE_CODE (exp) != VIEW_CONVERT_EXPR 4941 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE) 4942 /* Keep the conversion. */ 4943 break; 4944 else 4945 exp = TREE_OPERAND (exp, 0); 4946 } 4947 4948 code = TREE_CODE (TREE_TYPE (exp)); 4949 thissize = int_size_in_bytes (TREE_TYPE (exp)); 4950 4951 /* Allow a constructor with no elements for any data type. 4952 This means to fill the space with zeros. */ 4953 if (TREE_CODE (exp) == CONSTRUCTOR 4954 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp))) 4955 { 4956 assemble_zeros (size); 4957 return size; 4958 } 4959 4960 if (TREE_CODE (exp) == FDESC_EXPR) 4961 { 4962 #ifdef ASM_OUTPUT_FDESC 4963 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1)); 4964 tree decl = TREE_OPERAND (exp, 0); 4965 ASM_OUTPUT_FDESC (asm_out_file, decl, part); 4966 #else 4967 gcc_unreachable (); 4968 #endif 4969 return size; 4970 } 4971 4972 /* Now output the underlying data. If we've handling the padding, return. 4973 Otherwise, break and ensure SIZE is the size written. */ 4974 switch (code) 4975 { 4976 case BOOLEAN_TYPE: 4977 case INTEGER_TYPE: 4978 case ENUMERAL_TYPE: 4979 case POINTER_TYPE: 4980 case REFERENCE_TYPE: 4981 case OFFSET_TYPE: 4982 case FIXED_POINT_TYPE: 4983 case NULLPTR_TYPE: 4984 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER); 4985 if (reverse) 4986 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst); 4987 if (!assemble_integer (cst, MIN (size, thissize), align, 0)) 4988 error ("initializer for integer/fixed-point value is too complicated"); 4989 break; 4990 4991 case REAL_TYPE: 4992 if (TREE_CODE (exp) != REAL_CST) 4993 error ("initializer for floating value is not a floating constant"); 4994 else 4995 assemble_real (TREE_REAL_CST (exp), 4996 SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)), 4997 align, reverse); 4998 break; 4999 5000 case COMPLEX_TYPE: 5001 output_constant (TREE_REALPART (exp), thissize / 2, align, 5002 reverse, false); 5003 output_constant (TREE_IMAGPART (exp), thissize / 2, 5004 min_align (align, BITS_PER_UNIT * (thissize / 2)), 5005 reverse, false); 5006 break; 5007 5008 case ARRAY_TYPE: 5009 case VECTOR_TYPE: 5010 switch (TREE_CODE (exp)) 5011 { 5012 case CONSTRUCTOR: 5013 return output_constructor (exp, size, align, reverse, NULL); 5014 case STRING_CST: 5015 thissize = (unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp); 5016 if (merge_strings 5017 && (thissize == 0 5018 || TREE_STRING_POINTER (exp) [thissize - 1] != '\0')) 5019 thissize++; 5020 gcc_checking_assert (check_string_literal (exp, size)); 5021 assemble_string (TREE_STRING_POINTER (exp), thissize); 5022 break; 5023 case VECTOR_CST: 5024 { 5025 scalar_mode inner = SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (exp))); 5026 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner)); 5027 int elt_size = GET_MODE_SIZE (inner); 5028 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align, 5029 reverse, false); 5030 thissize = elt_size; 5031 /* Static constants must have a fixed size. */ 5032 unsigned int nunits = VECTOR_CST_NELTS (exp).to_constant (); 5033 for (unsigned int i = 1; i < nunits; i++) 5034 { 5035 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign, 5036 reverse, false); 5037 thissize += elt_size; 5038 } 5039 break; 5040 } 5041 default: 5042 gcc_unreachable (); 5043 } 5044 break; 5045 5046 case RECORD_TYPE: 5047 case UNION_TYPE: 5048 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR); 5049 return output_constructor (exp, size, align, reverse, NULL); 5050 5051 case ERROR_MARK: 5052 return 0; 5053 5054 default: 5055 gcc_unreachable (); 5056 } 5057 5058 if (size > thissize) 5059 assemble_zeros (size - thissize); 5060 5061 return size; 5062 } 5063 5064 /* Subroutine of output_constructor, used for computing the size of 5065 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array 5066 type with an unspecified upper bound. */ 5067 5068 static unsigned HOST_WIDE_INT 5069 array_size_for_constructor (tree val) 5070 { 5071 tree max_index; 5072 unsigned HOST_WIDE_INT cnt; 5073 tree index, value, tmp; 5074 offset_int i; 5075 5076 /* This code used to attempt to handle string constants that are not 5077 arrays of single-bytes, but nothing else does, so there's no point in 5078 doing it here. */ 5079 if (TREE_CODE (val) == STRING_CST) 5080 return TREE_STRING_LENGTH (val); 5081 5082 max_index = NULL_TREE; 5083 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value) 5084 { 5085 if (TREE_CODE (index) == RANGE_EXPR) 5086 index = TREE_OPERAND (index, 1); 5087 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index)) 5088 max_index = index; 5089 } 5090 5091 if (max_index == NULL_TREE) 5092 return 0; 5093 5094 /* Compute the total number of array elements. */ 5095 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val))); 5096 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1; 5097 5098 /* Multiply by the array element unit size to find number of bytes. */ 5099 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val)))); 5100 5101 gcc_assert (wi::fits_uhwi_p (i)); 5102 return i.to_uhwi (); 5103 } 5104 5105 /* Other datastructures + helpers for output_constructor. */ 5106 5107 /* output_constructor local state to support interaction with helpers. */ 5108 5109 struct oc_local_state { 5110 5111 /* Received arguments. */ 5112 tree exp; /* Constructor expression. */ 5113 tree type; /* Type of constructor expression. */ 5114 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */ 5115 unsigned int align; /* Known initial alignment. */ 5116 tree min_index; /* Lower bound if specified for an array. */ 5117 5118 /* Output processing state. */ 5119 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */ 5120 int byte; /* Part of a bitfield byte yet to be output. */ 5121 int last_relative_index; /* Implicit or explicit index of the last 5122 array element output within a bitfield. */ 5123 bool byte_buffer_in_use; /* Whether BYTE is in use. */ 5124 bool reverse; /* Whether reverse storage order is in use. */ 5125 5126 /* Current element. */ 5127 tree field; /* Current field decl in a record. */ 5128 tree val; /* Current element value. */ 5129 tree index; /* Current element index. */ 5130 5131 }; 5132 5133 /* Helper for output_constructor. From the current LOCAL state, output a 5134 RANGE_EXPR element. */ 5135 5136 static void 5137 output_constructor_array_range (oc_local_state *local) 5138 { 5139 unsigned HOST_WIDE_INT fieldsize 5140 = int_size_in_bytes (TREE_TYPE (local->type)); 5141 5142 HOST_WIDE_INT lo_index 5143 = tree_to_shwi (TREE_OPERAND (local->index, 0)); 5144 HOST_WIDE_INT hi_index 5145 = tree_to_shwi (TREE_OPERAND (local->index, 1)); 5146 HOST_WIDE_INT index; 5147 5148 unsigned int align2 5149 = min_align (local->align, fieldsize * BITS_PER_UNIT); 5150 5151 for (index = lo_index; index <= hi_index; index++) 5152 { 5153 /* Output the element's initial value. */ 5154 if (local->val == NULL_TREE) 5155 assemble_zeros (fieldsize); 5156 else 5157 fieldsize = output_constant (local->val, fieldsize, align2, 5158 local->reverse, false); 5159 5160 /* Count its size. */ 5161 local->total_bytes += fieldsize; 5162 } 5163 } 5164 5165 /* Helper for output_constructor. From the current LOCAL state, output a 5166 field element that is not true bitfield or part of an outer one. */ 5167 5168 static void 5169 output_constructor_regular_field (oc_local_state *local) 5170 { 5171 /* Field size and position. Since this structure is static, we know the 5172 positions are constant. */ 5173 unsigned HOST_WIDE_INT fieldsize; 5174 HOST_WIDE_INT fieldpos; 5175 5176 unsigned int align2; 5177 5178 /* Output any buffered-up bit-fields preceding this element. */ 5179 if (local->byte_buffer_in_use) 5180 { 5181 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1); 5182 local->total_bytes++; 5183 local->byte_buffer_in_use = false; 5184 } 5185 5186 if (local->index != NULL_TREE) 5187 { 5188 /* Perform the index calculation in modulo arithmetic but 5189 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs 5190 but we are using an unsigned sizetype. */ 5191 unsigned prec = TYPE_PRECISION (sizetype); 5192 offset_int idx = wi::sext (wi::to_offset (local->index) 5193 - wi::to_offset (local->min_index), prec); 5194 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val)))) 5195 .to_short_addr (); 5196 } 5197 else if (local->field != NULL_TREE) 5198 fieldpos = int_byte_position (local->field); 5199 else 5200 fieldpos = 0; 5201 5202 /* Advance to offset of this element. 5203 Note no alignment needed in an array, since that is guaranteed 5204 if each element has the proper size. */ 5205 if (local->field != NULL_TREE || local->index != NULL_TREE) 5206 { 5207 if (fieldpos > local->total_bytes) 5208 { 5209 assemble_zeros (fieldpos - local->total_bytes); 5210 local->total_bytes = fieldpos; 5211 } 5212 else 5213 /* Must not go backwards. */ 5214 gcc_assert (fieldpos == local->total_bytes); 5215 } 5216 5217 /* Find the alignment of this element. */ 5218 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos); 5219 5220 /* Determine size this element should occupy. */ 5221 if (local->field) 5222 { 5223 fieldsize = 0; 5224 5225 /* If this is an array with an unspecified upper bound, 5226 the initializer determines the size. */ 5227 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL, 5228 but we cannot do this until the deprecated support for 5229 initializing zero-length array members is removed. */ 5230 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE 5231 && (!TYPE_DOMAIN (TREE_TYPE (local->field)) 5232 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))) 5233 { 5234 fieldsize = array_size_for_constructor (local->val); 5235 /* Given a non-empty initialization, this field had better 5236 be last. Given a flexible array member, the next field 5237 on the chain is a TYPE_DECL of the enclosing struct. */ 5238 const_tree next = DECL_CHAIN (local->field); 5239 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL); 5240 tree size = TYPE_SIZE_UNIT (TREE_TYPE (local->val)); 5241 gcc_checking_assert (compare_tree_int (size, fieldsize) == 0); 5242 } 5243 else 5244 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field)); 5245 } 5246 else 5247 fieldsize = int_size_in_bytes (TREE_TYPE (local->type)); 5248 5249 /* Output the element's initial value. */ 5250 if (local->val == NULL_TREE) 5251 assemble_zeros (fieldsize); 5252 else 5253 fieldsize = output_constant (local->val, fieldsize, align2, 5254 local->reverse, false); 5255 5256 /* Count its size. */ 5257 local->total_bytes += fieldsize; 5258 } 5259 5260 /* Helper for output_constructor. From the LOCAL state, output an element 5261 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset 5262 from the start of a possibly ongoing outer byte buffer. */ 5263 5264 static void 5265 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset) 5266 { 5267 /* Bit size of this element. */ 5268 HOST_WIDE_INT ebitsize 5269 = (local->field 5270 ? tree_to_uhwi (DECL_SIZE (local->field)) 5271 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type)))); 5272 5273 /* Relative index of this element if this is an array component. */ 5274 HOST_WIDE_INT relative_index 5275 = (!local->field 5276 ? (local->index 5277 ? (tree_to_shwi (local->index) 5278 - tree_to_shwi (local->min_index)) 5279 : local->last_relative_index + 1) 5280 : 0); 5281 5282 /* Bit position of this element from the start of the containing 5283 constructor. */ 5284 HOST_WIDE_INT constructor_relative_ebitpos 5285 = (local->field 5286 ? int_bit_position (local->field) 5287 : ebitsize * relative_index); 5288 5289 /* Bit position of this element from the start of a possibly ongoing 5290 outer byte buffer. */ 5291 HOST_WIDE_INT byte_relative_ebitpos 5292 = bit_offset + constructor_relative_ebitpos; 5293 5294 /* From the start of a possibly ongoing outer byte buffer, offsets to 5295 the first bit of this element and to the first bit past the end of 5296 this element. */ 5297 HOST_WIDE_INT next_offset = byte_relative_ebitpos; 5298 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize; 5299 5300 local->last_relative_index = relative_index; 5301 5302 if (local->val == NULL_TREE) 5303 local->val = integer_zero_node; 5304 5305 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR 5306 || TREE_CODE (local->val) == NON_LVALUE_EXPR) 5307 local->val = TREE_OPERAND (local->val, 0); 5308 5309 if (TREE_CODE (local->val) != INTEGER_CST 5310 && TREE_CODE (local->val) != CONSTRUCTOR) 5311 { 5312 error ("invalid initial value for member %qE", DECL_NAME (local->field)); 5313 return; 5314 } 5315 5316 /* If this field does not start in this (or next) byte, skip some bytes. */ 5317 if (next_offset / BITS_PER_UNIT != local->total_bytes) 5318 { 5319 /* Output remnant of any bit field in previous bytes. */ 5320 if (local->byte_buffer_in_use) 5321 { 5322 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1); 5323 local->total_bytes++; 5324 local->byte_buffer_in_use = false; 5325 } 5326 5327 /* If still not at proper byte, advance to there. */ 5328 if (next_offset / BITS_PER_UNIT != local->total_bytes) 5329 { 5330 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes); 5331 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes); 5332 local->total_bytes = next_offset / BITS_PER_UNIT; 5333 } 5334 } 5335 5336 /* Set up the buffer if necessary. */ 5337 if (!local->byte_buffer_in_use) 5338 { 5339 local->byte = 0; 5340 if (ebitsize > 0) 5341 local->byte_buffer_in_use = true; 5342 } 5343 5344 /* If this is nested constructor, recurse passing the bit offset and the 5345 pending data, then retrieve the new pending data afterwards. */ 5346 if (TREE_CODE (local->val) == CONSTRUCTOR) 5347 { 5348 oc_outer_state temp_state; 5349 temp_state.bit_offset = next_offset % BITS_PER_UNIT; 5350 temp_state.byte = local->byte; 5351 local->total_bytes 5352 += output_constructor (local->val, 0, 0, local->reverse, &temp_state); 5353 local->byte = temp_state.byte; 5354 return; 5355 } 5356 5357 /* Otherwise, we must split the element into pieces that fall within 5358 separate bytes, and combine each byte with previous or following 5359 bit-fields. */ 5360 while (next_offset < end_offset) 5361 { 5362 int this_time; 5363 int shift; 5364 unsigned HOST_WIDE_INT value; 5365 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT; 5366 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT; 5367 5368 /* Advance from byte to byte within this element when necessary. */ 5369 while (next_byte != local->total_bytes) 5370 { 5371 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1); 5372 local->total_bytes++; 5373 local->byte = 0; 5374 } 5375 5376 /* Number of bits we can process at once (all part of the same byte). */ 5377 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit); 5378 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN) 5379 { 5380 /* For big-endian data, take the most significant bits (of the 5381 bits that are significant) first and put them into bytes from 5382 the most significant end. */ 5383 shift = end_offset - next_offset - this_time; 5384 5385 /* Don't try to take a bunch of bits that cross 5386 the word boundary in the INTEGER_CST. We can 5387 only select bits from one element. */ 5388 if ((shift / HOST_BITS_PER_WIDE_INT) 5389 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT)) 5390 { 5391 const int end = shift + this_time - 1; 5392 shift = end & -HOST_BITS_PER_WIDE_INT; 5393 this_time = end - shift + 1; 5394 } 5395 5396 /* Now get the bits we want to insert. */ 5397 value = wi::extract_uhwi (wi::to_widest (local->val), 5398 shift, this_time); 5399 5400 /* Get the result. This works only when: 5401 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */ 5402 local->byte |= value << (BITS_PER_UNIT - this_time - next_bit); 5403 } 5404 else 5405 { 5406 /* On little-endian machines, take the least significant bits of 5407 the value first and pack them starting at the least significant 5408 bits of the bytes. */ 5409 shift = next_offset - byte_relative_ebitpos; 5410 5411 /* Don't try to take a bunch of bits that cross 5412 the word boundary in the INTEGER_CST. We can 5413 only select bits from one element. */ 5414 if ((shift / HOST_BITS_PER_WIDE_INT) 5415 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT)) 5416 this_time 5417 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1)); 5418 5419 /* Now get the bits we want to insert. */ 5420 value = wi::extract_uhwi (wi::to_widest (local->val), 5421 shift, this_time); 5422 5423 /* Get the result. This works only when: 5424 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */ 5425 local->byte |= value << next_bit; 5426 } 5427 5428 next_offset += this_time; 5429 local->byte_buffer_in_use = true; 5430 } 5431 } 5432 5433 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants). 5434 Generate at least SIZE bytes, padding if necessary. OUTER designates the 5435 caller output state of relevance in recursive invocations. */ 5436 5437 static unsigned HOST_WIDE_INT 5438 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align, 5439 bool reverse, oc_outer_state *outer) 5440 { 5441 unsigned HOST_WIDE_INT cnt; 5442 constructor_elt *ce; 5443 oc_local_state local; 5444 5445 /* Setup our local state to communicate with helpers. */ 5446 local.exp = exp; 5447 local.type = TREE_TYPE (exp); 5448 local.size = size; 5449 local.align = align; 5450 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type)) 5451 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type)); 5452 else 5453 local.min_index = integer_zero_node; 5454 5455 local.total_bytes = 0; 5456 local.byte_buffer_in_use = outer != NULL; 5457 local.byte = outer ? outer->byte : 0; 5458 local.last_relative_index = -1; 5459 /* The storage order is specified for every aggregate type. */ 5460 if (AGGREGATE_TYPE_P (local.type)) 5461 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type); 5462 else 5463 local.reverse = reverse; 5464 5465 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT); 5466 5467 /* As CE goes through the elements of the constant, FIELD goes through the 5468 structure fields if the constant is a structure. If the constant is a 5469 union, we override this by getting the field from the TREE_LIST element. 5470 But the constant could also be an array. Then FIELD is zero. 5471 5472 There is always a maximum of one element in the chain LINK for unions 5473 (even if the initializer in a source program incorrectly contains 5474 more one). */ 5475 5476 if (TREE_CODE (local.type) == RECORD_TYPE) 5477 local.field = TYPE_FIELDS (local.type); 5478 else 5479 local.field = NULL_TREE; 5480 5481 for (cnt = 0; 5482 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce); 5483 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0) 5484 { 5485 local.val = ce->value; 5486 local.index = NULL_TREE; 5487 5488 /* The element in a union constructor specifies the proper field 5489 or index. */ 5490 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE) 5491 local.field = ce->index; 5492 5493 else if (TREE_CODE (local.type) == ARRAY_TYPE) 5494 local.index = ce->index; 5495 5496 if (local.field && flag_verbose_asm) 5497 fprintf (asm_out_file, "%s %s:\n", 5498 ASM_COMMENT_START, 5499 DECL_NAME (local.field) 5500 ? IDENTIFIER_POINTER (DECL_NAME (local.field)) 5501 : "<anonymous>"); 5502 5503 /* Eliminate the marker that makes a cast not be an lvalue. */ 5504 if (local.val != NULL_TREE) 5505 STRIP_NOPS (local.val); 5506 5507 /* Output the current element, using the appropriate helper ... */ 5508 5509 /* For an array slice not part of an outer bitfield. */ 5510 if (!outer 5511 && local.index != NULL_TREE 5512 && TREE_CODE (local.index) == RANGE_EXPR) 5513 output_constructor_array_range (&local); 5514 5515 /* For a field that is neither a true bitfield nor part of an outer one, 5516 known to be at least byte aligned and multiple-of-bytes long. */ 5517 else if (!outer 5518 && (local.field == NULL_TREE 5519 || !CONSTRUCTOR_BITFIELD_P (local.field))) 5520 output_constructor_regular_field (&local); 5521 5522 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are 5523 supported for scalar fields, so we may need to convert first. */ 5524 else 5525 { 5526 if (TREE_CODE (local.val) == REAL_CST) 5527 local.val 5528 = fold_unary (VIEW_CONVERT_EXPR, 5529 build_nonstandard_integer_type 5530 (TYPE_PRECISION (TREE_TYPE (local.val)), 0), 5531 local.val); 5532 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0); 5533 } 5534 } 5535 5536 /* If we are not at toplevel, save the pending data for our caller. 5537 Otherwise output the pending data and padding zeros as needed. */ 5538 if (outer) 5539 outer->byte = local.byte; 5540 else 5541 { 5542 if (local.byte_buffer_in_use) 5543 { 5544 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1); 5545 local.total_bytes++; 5546 } 5547 5548 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size) 5549 { 5550 assemble_zeros (local.size - local.total_bytes); 5551 local.total_bytes = local.size; 5552 } 5553 } 5554 5555 return local.total_bytes; 5556 } 5557 5558 /* Mark DECL as weak. */ 5559 5560 static void 5561 mark_weak (tree decl) 5562 { 5563 if (DECL_WEAK (decl)) 5564 return; 5565 5566 struct symtab_node *n = symtab_node::get (decl); 5567 if (n && n->refuse_visibility_changes) 5568 error ("%+qD declared weak after being used", decl); 5569 DECL_WEAK (decl) = 1; 5570 5571 if (DECL_RTL_SET_P (decl) 5572 && MEM_P (DECL_RTL (decl)) 5573 && XEXP (DECL_RTL (decl), 0) 5574 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF) 5575 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1; 5576 } 5577 5578 /* Merge weak status between NEWDECL and OLDDECL. */ 5579 5580 void 5581 merge_weak (tree newdecl, tree olddecl) 5582 { 5583 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl)) 5584 { 5585 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK) 5586 { 5587 tree *pwd; 5588 /* We put the NEWDECL on the weak_decls list at some point 5589 and OLDDECL as well. Keep just OLDDECL on the list. */ 5590 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd)) 5591 if (TREE_VALUE (*pwd) == newdecl) 5592 { 5593 *pwd = TREE_CHAIN (*pwd); 5594 break; 5595 } 5596 } 5597 return; 5598 } 5599 5600 if (DECL_WEAK (newdecl)) 5601 { 5602 tree wd; 5603 5604 /* NEWDECL is weak, but OLDDECL is not. */ 5605 5606 /* If we already output the OLDDECL, we're in trouble; we can't 5607 go back and make it weak. This should never happen in 5608 unit-at-a-time compilation. */ 5609 gcc_assert (!TREE_ASM_WRITTEN (olddecl)); 5610 5611 /* If we've already generated rtl referencing OLDDECL, we may 5612 have done so in a way that will not function properly with 5613 a weak symbol. Again in unit-at-a-time this should be 5614 impossible. */ 5615 gcc_assert (!TREE_USED (olddecl) 5616 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl))); 5617 5618 /* PR 49899: You cannot convert a static function into a weak, public function. */ 5619 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl)) 5620 error ("weak declaration of %q+D being applied to a already " 5621 "existing, static definition", newdecl); 5622 5623 if (TARGET_SUPPORTS_WEAK) 5624 { 5625 /* We put the NEWDECL on the weak_decls list at some point. 5626 Replace it with the OLDDECL. */ 5627 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd)) 5628 if (TREE_VALUE (wd) == newdecl) 5629 { 5630 TREE_VALUE (wd) = olddecl; 5631 break; 5632 } 5633 /* We may not find the entry on the list. If NEWDECL is a 5634 weak alias, then we will have already called 5635 globalize_decl to remove the entry; in that case, we do 5636 not need to do anything. */ 5637 } 5638 5639 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */ 5640 mark_weak (olddecl); 5641 } 5642 else 5643 /* OLDDECL was weak, but NEWDECL was not explicitly marked as 5644 weak. Just update NEWDECL to indicate that it's weak too. */ 5645 mark_weak (newdecl); 5646 } 5647 5648 /* Declare DECL to be a weak symbol. */ 5649 5650 void 5651 declare_weak (tree decl) 5652 { 5653 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl)); 5654 if (! TREE_PUBLIC (decl)) 5655 { 5656 error ("weak declaration of %q+D must be public", decl); 5657 return; 5658 } 5659 else if (!TARGET_SUPPORTS_WEAK) 5660 warning (0, "weak declaration of %q+D not supported", decl); 5661 5662 mark_weak (decl); 5663 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl))) 5664 DECL_ATTRIBUTES (decl) 5665 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl)); 5666 } 5667 5668 static void 5669 weak_finish_1 (tree decl) 5670 { 5671 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL) 5672 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 5673 #endif 5674 5675 if (! TREE_USED (decl)) 5676 return; 5677 5678 #ifdef ASM_WEAKEN_DECL 5679 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL); 5680 #else 5681 #ifdef ASM_WEAKEN_LABEL 5682 ASM_WEAKEN_LABEL (asm_out_file, name); 5683 #else 5684 #ifdef ASM_OUTPUT_WEAK_ALIAS 5685 { 5686 static bool warn_once = 0; 5687 if (! warn_once) 5688 { 5689 warning (0, "only weak aliases are supported in this configuration"); 5690 warn_once = 1; 5691 } 5692 return; 5693 } 5694 #endif 5695 #endif 5696 #endif 5697 } 5698 5699 /* Fiven an assembly name, find the decl it is associated with. */ 5700 static tree 5701 find_decl (tree target) 5702 { 5703 symtab_node *node = symtab_node::get_for_asmname (target); 5704 if (node) 5705 return node->decl; 5706 return NULL_TREE; 5707 } 5708 5709 /* This TREE_LIST contains weakref targets. */ 5710 5711 static GTY(()) tree weakref_targets; 5712 5713 /* Emit any pending weak declarations. */ 5714 5715 void 5716 weak_finish (void) 5717 { 5718 tree t; 5719 5720 for (t = weakref_targets; t; t = TREE_CHAIN (t)) 5721 { 5722 tree alias_decl = TREE_PURPOSE (t); 5723 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t)); 5724 5725 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)) 5726 || TREE_SYMBOL_REFERENCED (target)) 5727 /* Remove alias_decl from the weak list, but leave entries for 5728 the target alone. */ 5729 target = NULL_TREE; 5730 #ifndef ASM_OUTPUT_WEAKREF 5731 else if (! TREE_SYMBOL_REFERENCED (target)) 5732 { 5733 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not 5734 defined, otherwise we and weak_finish_1 would use 5735 different macros. */ 5736 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL 5737 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target)); 5738 # else 5739 tree decl = find_decl (target); 5740 5741 if (! decl) 5742 { 5743 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl), 5744 TREE_CODE (alias_decl), target, 5745 TREE_TYPE (alias_decl)); 5746 5747 DECL_EXTERNAL (decl) = 1; 5748 TREE_PUBLIC (decl) = 1; 5749 DECL_ARTIFICIAL (decl) = 1; 5750 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl); 5751 TREE_USED (decl) = 1; 5752 } 5753 5754 weak_finish_1 (decl); 5755 # endif 5756 } 5757 #endif 5758 5759 { 5760 tree *p; 5761 tree t2; 5762 5763 /* Remove the alias and the target from the pending weak list 5764 so that we do not emit any .weak directives for the former, 5765 nor multiple .weak directives for the latter. */ 5766 for (p = &weak_decls; (t2 = *p) ; ) 5767 { 5768 if (TREE_VALUE (t2) == alias_decl 5769 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2))) 5770 *p = TREE_CHAIN (t2); 5771 else 5772 p = &TREE_CHAIN (t2); 5773 } 5774 5775 /* Remove other weakrefs to the same target, to speed things up. */ 5776 for (p = &TREE_CHAIN (t); (t2 = *p) ; ) 5777 { 5778 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2))) 5779 *p = TREE_CHAIN (t2); 5780 else 5781 p = &TREE_CHAIN (t2); 5782 } 5783 } 5784 } 5785 5786 for (t = weak_decls; t; t = TREE_CHAIN (t)) 5787 { 5788 tree decl = TREE_VALUE (t); 5789 5790 weak_finish_1 (decl); 5791 } 5792 } 5793 5794 /* Emit the assembly bits to indicate that DECL is globally visible. */ 5795 5796 static void 5797 globalize_decl (tree decl) 5798 { 5799 5800 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL) 5801 if (DECL_WEAK (decl)) 5802 { 5803 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 5804 tree *p, t; 5805 5806 #ifdef ASM_WEAKEN_DECL 5807 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0); 5808 #else 5809 ASM_WEAKEN_LABEL (asm_out_file, name); 5810 #endif 5811 5812 /* Remove this function from the pending weak list so that 5813 we do not emit multiple .weak directives for it. */ 5814 for (p = &weak_decls; (t = *p) ; ) 5815 { 5816 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))) 5817 *p = TREE_CHAIN (t); 5818 else 5819 p = &TREE_CHAIN (t); 5820 } 5821 5822 /* Remove weakrefs to the same target from the pending weakref 5823 list, for the same reason. */ 5824 for (p = &weakref_targets; (t = *p) ; ) 5825 { 5826 if (DECL_ASSEMBLER_NAME (decl) 5827 == ultimate_transparent_alias_target (&TREE_VALUE (t))) 5828 *p = TREE_CHAIN (t); 5829 else 5830 p = &TREE_CHAIN (t); 5831 } 5832 5833 return; 5834 } 5835 #endif 5836 5837 targetm.asm_out.globalize_decl_name (asm_out_file, decl); 5838 } 5839 5840 vec<alias_pair, va_gc> *alias_pairs; 5841 5842 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF 5843 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose 5844 tree node is DECL to have the value of the tree node TARGET. */ 5845 5846 void 5847 do_assemble_alias (tree decl, tree target) 5848 { 5849 tree id; 5850 5851 /* Emulated TLS had better not get this var. */ 5852 gcc_assert (!(!targetm.have_tls 5853 && VAR_P (decl) 5854 && DECL_THREAD_LOCAL_P (decl))); 5855 5856 if (TREE_ASM_WRITTEN (decl)) 5857 return; 5858 5859 id = DECL_ASSEMBLER_NAME (decl); 5860 ultimate_transparent_alias_target (&id); 5861 ultimate_transparent_alias_target (&target); 5862 5863 /* We must force creation of DECL_RTL for debug info generation, even though 5864 we don't use it here. */ 5865 make_decl_rtl (decl); 5866 5867 TREE_ASM_WRITTEN (decl) = 1; 5868 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1; 5869 TREE_ASM_WRITTEN (id) = 1; 5870 5871 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))) 5872 { 5873 if (!TREE_SYMBOL_REFERENCED (target)) 5874 weakref_targets = tree_cons (decl, target, weakref_targets); 5875 5876 #ifdef ASM_OUTPUT_WEAKREF 5877 ASM_OUTPUT_WEAKREF (asm_out_file, decl, 5878 IDENTIFIER_POINTER (id), 5879 IDENTIFIER_POINTER (target)); 5880 #else 5881 if (!TARGET_SUPPORTS_WEAK) 5882 { 5883 error_at (DECL_SOURCE_LOCATION (decl), 5884 "weakref is not supported in this configuration"); 5885 return; 5886 } 5887 #endif 5888 return; 5889 } 5890 5891 #ifdef ASM_OUTPUT_DEF 5892 tree orig_decl = decl; 5893 5894 /* Make name accessible from other files, if appropriate. */ 5895 5896 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl)) 5897 { 5898 globalize_decl (decl); 5899 maybe_assemble_visibility (decl); 5900 } 5901 if (TREE_CODE (decl) == FUNCTION_DECL 5902 && cgraph_node::get (decl)->ifunc_resolver) 5903 { 5904 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE) 5905 if (targetm.has_ifunc_p ()) 5906 ASM_OUTPUT_TYPE_DIRECTIVE 5907 (asm_out_file, IDENTIFIER_POINTER (id), 5908 IFUNC_ASM_TYPE); 5909 else 5910 #endif 5911 error_at (DECL_SOURCE_LOCATION (decl), 5912 "ifunc is not supported on this target"); 5913 } 5914 5915 # ifdef ASM_OUTPUT_DEF_FROM_DECLS 5916 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target); 5917 # else 5918 ASM_OUTPUT_DEF (asm_out_file, 5919 IDENTIFIER_POINTER (id), 5920 IDENTIFIER_POINTER (target)); 5921 # endif 5922 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL) 5923 { 5924 const char *name; 5925 tree *p, t; 5926 5927 name = IDENTIFIER_POINTER (id); 5928 # ifdef ASM_WEAKEN_DECL 5929 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target)); 5930 # else 5931 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target)); 5932 # endif 5933 /* Remove this function from the pending weak list so that 5934 we do not emit multiple .weak directives for it. */ 5935 for (p = &weak_decls; (t = *p) ; ) 5936 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)) 5937 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t))) 5938 *p = TREE_CHAIN (t); 5939 else 5940 p = &TREE_CHAIN (t); 5941 5942 /* Remove weakrefs to the same target from the pending weakref 5943 list, for the same reason. */ 5944 for (p = &weakref_targets; (t = *p) ; ) 5945 { 5946 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t))) 5947 *p = TREE_CHAIN (t); 5948 else 5949 p = &TREE_CHAIN (t); 5950 } 5951 } 5952 #endif 5953 } 5954 5955 /* Emit an assembler directive to make the symbol for DECL an alias to 5956 the symbol for TARGET. */ 5957 5958 void 5959 assemble_alias (tree decl, tree target) 5960 { 5961 tree target_decl; 5962 5963 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))) 5964 { 5965 tree alias = DECL_ASSEMBLER_NAME (decl); 5966 5967 ultimate_transparent_alias_target (&target); 5968 5969 if (alias == target) 5970 error ("weakref %q+D ultimately targets itself", decl); 5971 if (TREE_PUBLIC (decl)) 5972 error ("weakref %q+D must have static linkage", decl); 5973 } 5974 else 5975 { 5976 #if !defined (ASM_OUTPUT_DEF) 5977 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL) 5978 error_at (DECL_SOURCE_LOCATION (decl), 5979 "alias definitions not supported in this configuration"); 5980 TREE_ASM_WRITTEN (decl) = 1; 5981 return; 5982 # else 5983 if (!DECL_WEAK (decl)) 5984 { 5985 /* NB: ifunc_resolver isn't set when an error is detected. */ 5986 if (TREE_CODE (decl) == FUNCTION_DECL 5987 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl))) 5988 error_at (DECL_SOURCE_LOCATION (decl), 5989 "ifunc is not supported in this configuration"); 5990 else 5991 error_at (DECL_SOURCE_LOCATION (decl), 5992 "only weak aliases are supported in this configuration"); 5993 TREE_ASM_WRITTEN (decl) = 1; 5994 return; 5995 } 5996 # endif 5997 #endif 5998 } 5999 TREE_USED (decl) = 1; 6000 6001 /* Allow aliases to aliases. */ 6002 if (TREE_CODE (decl) == FUNCTION_DECL) 6003 cgraph_node::get_create (decl)->alias = true; 6004 else 6005 varpool_node::get_create (decl)->alias = true; 6006 6007 /* If the target has already been emitted, we don't have to queue the 6008 alias. This saves a tad of memory. */ 6009 if (symtab->global_info_ready) 6010 target_decl = find_decl (target); 6011 else 6012 target_decl= NULL; 6013 if ((target_decl && TREE_ASM_WRITTEN (target_decl)) 6014 || symtab->state >= EXPANSION) 6015 do_assemble_alias (decl, target); 6016 else 6017 { 6018 alias_pair p = {decl, target}; 6019 vec_safe_push (alias_pairs, p); 6020 } 6021 } 6022 6023 /* Record and output a table of translations from original function 6024 to its transaction aware clone. Note that tm_pure functions are 6025 considered to be their own clone. */ 6026 6027 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map> 6028 { 6029 static hashval_t hash (tree_map *m) { return tree_map_hash (m); } 6030 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); } 6031 6032 static int 6033 keep_cache_entry (tree_map *&e) 6034 { 6035 return ggc_marked_p (e->base.from); 6036 } 6037 }; 6038 6039 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash; 6040 6041 void 6042 record_tm_clone_pair (tree o, tree n) 6043 { 6044 struct tree_map **slot, *h; 6045 6046 if (tm_clone_hash == NULL) 6047 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32); 6048 6049 h = ggc_alloc<tree_map> (); 6050 h->hash = htab_hash_pointer (o); 6051 h->base.from = o; 6052 h->to = n; 6053 6054 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT); 6055 *slot = h; 6056 } 6057 6058 tree 6059 get_tm_clone_pair (tree o) 6060 { 6061 if (tm_clone_hash) 6062 { 6063 struct tree_map *h, in; 6064 6065 in.base.from = o; 6066 in.hash = htab_hash_pointer (o); 6067 h = tm_clone_hash->find_with_hash (&in, in.hash); 6068 if (h) 6069 return h->to; 6070 } 6071 return NULL_TREE; 6072 } 6073 6074 struct tm_alias_pair 6075 { 6076 unsigned int uid; 6077 tree from; 6078 tree to; 6079 }; 6080 6081 6082 /* Dump the actual pairs to the .tm_clone_table section. */ 6083 6084 static void 6085 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs) 6086 { 6087 unsigned i; 6088 tm_alias_pair *p; 6089 bool switched = false; 6090 6091 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p) 6092 { 6093 tree src = p->from; 6094 tree dst = p->to; 6095 struct cgraph_node *src_n = cgraph_node::get (src); 6096 struct cgraph_node *dst_n = cgraph_node::get (dst); 6097 6098 /* The function ipa_tm_create_version() marks the clone as needed if 6099 the original function was needed. But we also mark the clone as 6100 needed if we ever called the clone indirectly through 6101 TM_GETTMCLONE. If neither of these are true, we didn't generate 6102 a clone, and we didn't call it indirectly... no sense keeping it 6103 in the clone table. */ 6104 if (!dst_n || !dst_n->definition) 6105 continue; 6106 6107 /* This covers the case where we have optimized the original 6108 function away, and only access the transactional clone. */ 6109 if (!src_n || !src_n->definition) 6110 continue; 6111 6112 if (!switched) 6113 { 6114 switch_to_section (targetm.asm_out.tm_clone_table_section ()); 6115 assemble_align (POINTER_SIZE); 6116 switched = true; 6117 } 6118 6119 assemble_integer (XEXP (DECL_RTL (src), 0), 6120 POINTER_SIZE_UNITS, POINTER_SIZE, 1); 6121 assemble_integer (XEXP (DECL_RTL (dst), 0), 6122 POINTER_SIZE_UNITS, POINTER_SIZE, 1); 6123 } 6124 } 6125 6126 /* Provide a default for the tm_clone_table section. */ 6127 6128 section * 6129 default_clone_table_section (void) 6130 { 6131 return get_named_section (NULL, ".tm_clone_table", 3); 6132 } 6133 6134 /* Helper comparison function for qsorting by the DECL_UID stored in 6135 alias_pair->emitted_diags. */ 6136 6137 static int 6138 tm_alias_pair_cmp (const void *x, const void *y) 6139 { 6140 const tm_alias_pair *p1 = (const tm_alias_pair *) x; 6141 const tm_alias_pair *p2 = (const tm_alias_pair *) y; 6142 if (p1->uid < p2->uid) 6143 return -1; 6144 if (p1->uid > p2->uid) 6145 return 1; 6146 return 0; 6147 } 6148 6149 void 6150 finish_tm_clone_pairs (void) 6151 { 6152 vec<tm_alias_pair> tm_alias_pairs = vNULL; 6153 6154 if (tm_clone_hash == NULL) 6155 return; 6156 6157 /* We need a determenistic order for the .tm_clone_table, otherwise 6158 we will get bootstrap comparison failures, so dump the hash table 6159 to a vector, sort it, and dump the vector. */ 6160 6161 /* Dump the hashtable to a vector. */ 6162 tree_map *map; 6163 hash_table<tm_clone_hasher>::iterator iter; 6164 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter) 6165 { 6166 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to}; 6167 tm_alias_pairs.safe_push (p); 6168 } 6169 /* Sort it. */ 6170 tm_alias_pairs.qsort (tm_alias_pair_cmp); 6171 6172 /* Dump it. */ 6173 dump_tm_clone_pairs (tm_alias_pairs); 6174 6175 tm_clone_hash->empty (); 6176 tm_clone_hash = NULL; 6177 tm_alias_pairs.release (); 6178 } 6179 6180 6181 /* Emit an assembler directive to set symbol for DECL visibility to 6182 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */ 6183 6184 void 6185 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED, 6186 int vis ATTRIBUTE_UNUSED) 6187 { 6188 #ifdef HAVE_GAS_HIDDEN 6189 static const char * const visibility_types[] = { 6190 NULL, "protected", "hidden", "internal" 6191 }; 6192 6193 const char *name, *type; 6194 tree id; 6195 6196 id = DECL_ASSEMBLER_NAME (decl); 6197 ultimate_transparent_alias_target (&id); 6198 name = IDENTIFIER_POINTER (id); 6199 6200 type = visibility_types[vis]; 6201 6202 fprintf (asm_out_file, "\t.%s\t", type); 6203 assemble_name (asm_out_file, name); 6204 fprintf (asm_out_file, "\n"); 6205 #else 6206 if (!DECL_ARTIFICIAL (decl)) 6207 warning (OPT_Wattributes, "visibility attribute not supported " 6208 "in this configuration; ignored"); 6209 #endif 6210 } 6211 6212 /* A helper function to call assemble_visibility when needed for a decl. */ 6213 6214 int 6215 maybe_assemble_visibility (tree decl) 6216 { 6217 enum symbol_visibility vis = DECL_VISIBILITY (decl); 6218 if (vis != VISIBILITY_DEFAULT) 6219 { 6220 targetm.asm_out.assemble_visibility (decl, vis); 6221 return 1; 6222 } 6223 else 6224 return 0; 6225 } 6226 6227 /* Returns 1 if the target configuration supports defining public symbols 6228 so that one of them will be chosen at link time instead of generating a 6229 multiply-defined symbol error, whether through the use of weak symbols or 6230 a target-specific mechanism for having duplicates discarded. */ 6231 6232 int 6233 supports_one_only (void) 6234 { 6235 if (SUPPORTS_ONE_ONLY) 6236 return 1; 6237 return TARGET_SUPPORTS_WEAK; 6238 } 6239 6240 /* Set up DECL as a public symbol that can be defined in multiple 6241 translation units without generating a linker error. */ 6242 6243 void 6244 make_decl_one_only (tree decl, tree comdat_group) 6245 { 6246 struct symtab_node *symbol; 6247 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl)); 6248 6249 TREE_PUBLIC (decl) = 1; 6250 6251 if (VAR_P (decl)) 6252 symbol = varpool_node::get_create (decl); 6253 else 6254 symbol = cgraph_node::get_create (decl); 6255 6256 if (SUPPORTS_ONE_ONLY) 6257 { 6258 #ifdef MAKE_DECL_ONE_ONLY 6259 MAKE_DECL_ONE_ONLY (decl); 6260 #endif 6261 symbol->set_comdat_group (comdat_group); 6262 } 6263 else if (VAR_P (decl) 6264 && (DECL_INITIAL (decl) == 0 6265 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node))) 6266 DECL_COMMON (decl) = 1; 6267 else 6268 { 6269 gcc_assert (TARGET_SUPPORTS_WEAK); 6270 DECL_WEAK (decl) = 1; 6271 } 6272 } 6273 6274 void 6275 init_varasm_once (void) 6276 { 6277 section_htab = hash_table<section_hasher>::create_ggc (31); 6278 object_block_htab = hash_table<object_block_hasher>::create_ggc (31); 6279 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009); 6280 6281 shared_constant_pool = create_constant_pool (); 6282 6283 #ifdef TEXT_SECTION_ASM_OP 6284 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op, 6285 TEXT_SECTION_ASM_OP); 6286 #endif 6287 6288 #ifdef DATA_SECTION_ASM_OP 6289 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op, 6290 DATA_SECTION_ASM_OP); 6291 #endif 6292 6293 #ifdef SDATA_SECTION_ASM_OP 6294 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op, 6295 SDATA_SECTION_ASM_OP); 6296 #endif 6297 6298 #ifdef READONLY_DATA_SECTION_ASM_OP 6299 readonly_data_section = get_unnamed_section (0, output_section_asm_op, 6300 READONLY_DATA_SECTION_ASM_OP); 6301 #endif 6302 6303 #ifdef CTORS_SECTION_ASM_OP 6304 ctors_section = get_unnamed_section (0, output_section_asm_op, 6305 CTORS_SECTION_ASM_OP); 6306 #endif 6307 6308 #ifdef DTORS_SECTION_ASM_OP 6309 dtors_section = get_unnamed_section (0, output_section_asm_op, 6310 DTORS_SECTION_ASM_OP); 6311 #endif 6312 6313 #ifdef BSS_SECTION_ASM_OP 6314 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS, 6315 output_section_asm_op, 6316 BSS_SECTION_ASM_OP); 6317 #endif 6318 6319 #ifdef SBSS_SECTION_ASM_OP 6320 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS, 6321 output_section_asm_op, 6322 SBSS_SECTION_ASM_OP); 6323 #endif 6324 6325 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS 6326 | SECTION_COMMON, emit_tls_common); 6327 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS 6328 | SECTION_COMMON, emit_local); 6329 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS 6330 | SECTION_COMMON, emit_common); 6331 6332 #if defined ASM_OUTPUT_ALIGNED_BSS 6333 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS, 6334 emit_bss); 6335 #endif 6336 6337 targetm.asm_out.init_sections (); 6338 6339 if (readonly_data_section == NULL) 6340 readonly_data_section = text_section; 6341 6342 #ifdef ASM_OUTPUT_EXTERNAL 6343 pending_assemble_externals_set = new hash_set<tree>; 6344 #endif 6345 } 6346 6347 enum tls_model 6348 decl_default_tls_model (const_tree decl) 6349 { 6350 enum tls_model kind; 6351 bool is_local; 6352 6353 is_local = targetm.binds_local_p (decl); 6354 if (!flag_shlib) 6355 { 6356 if (is_local) 6357 kind = TLS_MODEL_LOCAL_EXEC; 6358 else 6359 kind = TLS_MODEL_INITIAL_EXEC; 6360 } 6361 6362 /* Local dynamic is inefficient when we're not combining the 6363 parts of the address. */ 6364 else if (optimize && is_local) 6365 kind = TLS_MODEL_LOCAL_DYNAMIC; 6366 else 6367 kind = TLS_MODEL_GLOBAL_DYNAMIC; 6368 if (kind < flag_tls_default) 6369 kind = flag_tls_default; 6370 6371 return kind; 6372 } 6373 6374 /* Select a set of attributes for section NAME based on the properties 6375 of DECL and whether or not RELOC indicates that DECL's initializer 6376 might contain runtime relocations. 6377 6378 We make the section read-only and executable for a function decl, 6379 read-only for a const data decl, and writable for a non-const data decl. */ 6380 6381 unsigned int 6382 default_section_type_flags (tree decl, const char *name, int reloc) 6383 { 6384 unsigned int flags; 6385 6386 if (decl && TREE_CODE (decl) == FUNCTION_DECL) 6387 flags = SECTION_CODE; 6388 else if (decl) 6389 { 6390 enum section_category category 6391 = categorize_decl_for_section (decl, reloc); 6392 if (decl_readonly_section_1 (category)) 6393 flags = 0; 6394 else if (category == SECCAT_DATA_REL_RO 6395 || category == SECCAT_DATA_REL_RO_LOCAL) 6396 flags = SECTION_WRITE | SECTION_RELRO; 6397 else 6398 flags = SECTION_WRITE; 6399 } 6400 else 6401 { 6402 flags = SECTION_WRITE; 6403 if (strcmp (name, ".data.rel.ro") == 0 6404 || strcmp (name, ".data.rel.ro.local") == 0) 6405 flags |= SECTION_RELRO; 6406 } 6407 6408 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl)) 6409 flags |= SECTION_LINKONCE; 6410 6411 if (strcmp (name, ".vtable_map_vars") == 0) 6412 flags |= SECTION_LINKONCE; 6413 6414 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl)) 6415 flags |= SECTION_TLS | SECTION_WRITE; 6416 6417 if (strcmp (name, ".bss") == 0 6418 || strncmp (name, ".bss.", 5) == 0 6419 || strncmp (name, ".gnu.linkonce.b.", 16) == 0 6420 || strcmp (name, ".persistent.bss") == 0 6421 || strcmp (name, ".sbss") == 0 6422 || strncmp (name, ".sbss.", 6) == 0 6423 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0) 6424 flags |= SECTION_BSS; 6425 6426 if (strcmp (name, ".tdata") == 0 6427 || strncmp (name, ".tdata.", 7) == 0 6428 || strncmp (name, ".gnu.linkonce.td.", 17) == 0) 6429 flags |= SECTION_TLS; 6430 6431 if (strcmp (name, ".tbss") == 0 6432 || strncmp (name, ".tbss.", 6) == 0 6433 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0) 6434 flags |= SECTION_TLS | SECTION_BSS; 6435 6436 /* Various sections have special ELF types that the assembler will 6437 assign by default based on the name. They are neither SHT_PROGBITS 6438 nor SHT_NOBITS, so when changing sections we don't want to print a 6439 section type (@progbits or @nobits). Rather than duplicating the 6440 assembler's knowledge of what those special name patterns are, just 6441 let the assembler choose the type if we don't know a specific 6442 reason to set it to something other than the default. SHT_PROGBITS 6443 is the default for sections whose name is not specially known to 6444 the assembler, so it does no harm to leave the choice to the 6445 assembler when @progbits is the best thing we know to use. If 6446 someone is silly enough to emit code or TLS variables to one of 6447 these sections, then don't handle them specially. 6448 6449 default_elf_asm_named_section (below) handles the BSS, TLS, ENTSIZE, and 6450 LINKONCE cases when NOTYPE is not set, so leave those to its logic. */ 6451 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE)) 6452 && !(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))) 6453 flags |= SECTION_NOTYPE; 6454 6455 return flags; 6456 } 6457 6458 /* Return true if the target supports some form of global BSS, 6459 either through bss_noswitch_section, or by selecting a BSS 6460 section in TARGET_ASM_SELECT_SECTION. */ 6461 6462 bool 6463 have_global_bss_p (void) 6464 { 6465 return bss_noswitch_section || targetm.have_switchable_bss_sections; 6466 } 6467 6468 /* Output assembly to switch to section NAME with attribute FLAGS. 6469 Four variants for common object file formats. */ 6470 6471 void 6472 default_no_named_section (const char *name ATTRIBUTE_UNUSED, 6473 unsigned int flags ATTRIBUTE_UNUSED, 6474 tree decl ATTRIBUTE_UNUSED) 6475 { 6476 /* Some object formats don't support named sections at all. The 6477 front-end should already have flagged this as an error. */ 6478 gcc_unreachable (); 6479 } 6480 6481 #ifndef TLS_SECTION_ASM_FLAG 6482 #define TLS_SECTION_ASM_FLAG 'T' 6483 #endif 6484 6485 void 6486 default_elf_asm_named_section (const char *name, unsigned int flags, 6487 tree decl) 6488 { 6489 char flagchars[11], *f = flagchars; 6490 unsigned int numeric_value = 0; 6491 6492 /* If we have already declared this section, we can use an 6493 abbreviated form to switch back to it -- unless this section is 6494 part of a COMDAT groups, in which case GAS requires the full 6495 declaration every time. */ 6496 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE)) 6497 && (flags & SECTION_DECLARED)) 6498 { 6499 fprintf (asm_out_file, "\t.section\t%s\n", name); 6500 return; 6501 } 6502 6503 /* If we have a machine specific flag, then use the numeric value to pass 6504 this on to GAS. */ 6505 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value)) 6506 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value); 6507 else 6508 { 6509 if (!(flags & SECTION_DEBUG)) 6510 *f++ = 'a'; 6511 #if HAVE_GAS_SECTION_EXCLUDE 6512 if (flags & SECTION_EXCLUDE) 6513 *f++ = 'e'; 6514 #endif 6515 if (flags & SECTION_WRITE) 6516 *f++ = 'w'; 6517 if (flags & SECTION_CODE) 6518 *f++ = 'x'; 6519 if (flags & SECTION_SMALL) 6520 *f++ = 's'; 6521 if (flags & SECTION_MERGE) 6522 *f++ = 'M'; 6523 if (flags & SECTION_STRINGS) 6524 *f++ = 'S'; 6525 if (flags & SECTION_TLS) 6526 *f++ = TLS_SECTION_ASM_FLAG; 6527 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE)) 6528 *f++ = 'G'; 6529 #ifdef MACH_DEP_SECTION_ASM_FLAG 6530 if (flags & SECTION_MACH_DEP) 6531 *f++ = MACH_DEP_SECTION_ASM_FLAG; 6532 #endif 6533 *f = '\0'; 6534 } 6535 6536 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars); 6537 6538 /* default_section_type_flags (above) knows which flags need special 6539 handling here, and sets NOTYPE when none of these apply so that the 6540 assembler's logic for default types can apply to user-chosen 6541 section names. */ 6542 if (!(flags & SECTION_NOTYPE)) 6543 { 6544 const char *type; 6545 const char *format; 6546 6547 if (flags & SECTION_BSS) 6548 type = "nobits"; 6549 else 6550 type = "progbits"; 6551 6552 format = ",@%s"; 6553 /* On platforms that use "@" as the assembly comment character, 6554 use "%" instead. */ 6555 if (strcmp (ASM_COMMENT_START, "@") == 0) 6556 format = ",%%%s"; 6557 fprintf (asm_out_file, format, type); 6558 6559 if (flags & SECTION_ENTSIZE) 6560 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE); 6561 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE)) 6562 { 6563 if (TREE_CODE (decl) == IDENTIFIER_NODE) 6564 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl)); 6565 else 6566 fprintf (asm_out_file, ",%s,comdat", 6567 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl))); 6568 } 6569 } 6570 6571 putc ('\n', asm_out_file); 6572 } 6573 6574 void 6575 default_coff_asm_named_section (const char *name, unsigned int flags, 6576 tree decl ATTRIBUTE_UNUSED) 6577 { 6578 char flagchars[8], *f = flagchars; 6579 6580 if (flags & SECTION_WRITE) 6581 *f++ = 'w'; 6582 if (flags & SECTION_CODE) 6583 *f++ = 'x'; 6584 *f = '\0'; 6585 6586 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars); 6587 } 6588 6589 void 6590 default_pe_asm_named_section (const char *name, unsigned int flags, 6591 tree decl) 6592 { 6593 default_coff_asm_named_section (name, flags, decl); 6594 6595 if (flags & SECTION_LINKONCE) 6596 { 6597 /* Functions may have been compiled at various levels of 6598 optimization so we can't use `same_size' here. 6599 Instead, have the linker pick one. */ 6600 fprintf (asm_out_file, "\t.linkonce %s\n", 6601 (flags & SECTION_CODE ? "discard" : "same_size")); 6602 } 6603 } 6604 6605 /* The lame default section selector. */ 6606 6607 section * 6608 default_select_section (tree decl, int reloc, 6609 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED) 6610 { 6611 if (DECL_P (decl)) 6612 { 6613 if (decl_readonly_section (decl, reloc)) 6614 return readonly_data_section; 6615 } 6616 else if (TREE_CODE (decl) == CONSTRUCTOR) 6617 { 6618 if (! ((flag_pic && reloc) 6619 || !TREE_READONLY (decl) 6620 || TREE_SIDE_EFFECTS (decl) 6621 || !TREE_CONSTANT (decl))) 6622 return readonly_data_section; 6623 } 6624 else if (TREE_CODE (decl) == STRING_CST) 6625 return readonly_data_section; 6626 else if (! (flag_pic && reloc)) 6627 return readonly_data_section; 6628 6629 return data_section; 6630 } 6631 6632 enum section_category 6633 categorize_decl_for_section (const_tree decl, int reloc) 6634 { 6635 enum section_category ret; 6636 6637 if (TREE_CODE (decl) == FUNCTION_DECL) 6638 return SECCAT_TEXT; 6639 else if (TREE_CODE (decl) == STRING_CST) 6640 { 6641 if ((flag_sanitize & SANITIZE_ADDRESS) 6642 && asan_protect_global (CONST_CAST_TREE (decl))) 6643 /* or !flag_merge_constants */ 6644 return SECCAT_RODATA; 6645 else 6646 return SECCAT_RODATA_MERGE_STR; 6647 } 6648 else if (VAR_P (decl)) 6649 { 6650 tree d = CONST_CAST_TREE (decl); 6651 if (bss_initializer_p (decl)) 6652 ret = SECCAT_BSS; 6653 else if (! TREE_READONLY (decl) 6654 || TREE_SIDE_EFFECTS (decl) 6655 || (DECL_INITIAL (decl) 6656 && ! TREE_CONSTANT (DECL_INITIAL (decl)))) 6657 { 6658 /* Here the reloc_rw_mask is not testing whether the section should 6659 be read-only or not, but whether the dynamic link will have to 6660 do something. If so, we wish to segregate the data in order to 6661 minimize cache misses inside the dynamic linker. */ 6662 if (reloc & targetm.asm_out.reloc_rw_mask ()) 6663 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL; 6664 else 6665 ret = SECCAT_DATA; 6666 } 6667 else if (reloc & targetm.asm_out.reloc_rw_mask ()) 6668 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO; 6669 else if (reloc || flag_merge_constants < 2 6670 || ((flag_sanitize & SANITIZE_ADDRESS) 6671 /* PR 81697: for architectures that use section anchors we 6672 need to ignore DECL_RTL_SET_P (decl) for string constants 6673 inside this asan_protect_global call because otherwise 6674 we'll wrongly put them into SECCAT_RODATA_MERGE_CONST 6675 section, set DECL_RTL (decl) later on and add DECL to 6676 protected globals via successive asan_protect_global 6677 calls. In this scenario we'll end up with wrong 6678 alignment of these strings at runtime and possible ASan 6679 false positives. */ 6680 && asan_protect_global (d, use_object_blocks_p () 6681 && use_blocks_for_decl_p (d)))) 6682 /* C and C++ don't allow different variables to share the same 6683 location. -fmerge-all-constants allows even that (at the 6684 expense of not conforming). */ 6685 ret = SECCAT_RODATA; 6686 else if (DECL_INITIAL (decl) 6687 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST) 6688 ret = SECCAT_RODATA_MERGE_STR_INIT; 6689 else 6690 ret = SECCAT_RODATA_MERGE_CONST; 6691 } 6692 else if (TREE_CODE (decl) == CONSTRUCTOR) 6693 { 6694 if ((reloc & targetm.asm_out.reloc_rw_mask ()) 6695 || TREE_SIDE_EFFECTS (decl) 6696 || ! TREE_CONSTANT (decl)) 6697 ret = SECCAT_DATA; 6698 else 6699 ret = SECCAT_RODATA; 6700 } 6701 else 6702 ret = SECCAT_RODATA; 6703 6704 /* There are no read-only thread-local sections. */ 6705 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl)) 6706 { 6707 /* Note that this would be *just* SECCAT_BSS, except that there's 6708 no concept of a read-only thread-local-data section. */ 6709 if (ret == SECCAT_BSS 6710 || DECL_INITIAL (decl) == NULL 6711 || (flag_zero_initialized_in_bss 6712 && initializer_zerop (DECL_INITIAL (decl)))) 6713 ret = SECCAT_TBSS; 6714 else 6715 ret = SECCAT_TDATA; 6716 } 6717 6718 /* If the target uses small data sections, select it. */ 6719 else if (targetm.in_small_data_p (decl)) 6720 { 6721 if (ret == SECCAT_BSS) 6722 ret = SECCAT_SBSS; 6723 else if (targetm.have_srodata_section && ret == SECCAT_RODATA) 6724 ret = SECCAT_SRODATA; 6725 else 6726 ret = SECCAT_SDATA; 6727 } 6728 6729 return ret; 6730 } 6731 6732 static bool 6733 decl_readonly_section_1 (enum section_category category) 6734 { 6735 switch (category) 6736 { 6737 case SECCAT_RODATA: 6738 case SECCAT_RODATA_MERGE_STR: 6739 case SECCAT_RODATA_MERGE_STR_INIT: 6740 case SECCAT_RODATA_MERGE_CONST: 6741 case SECCAT_SRODATA: 6742 return true; 6743 default: 6744 return false; 6745 } 6746 } 6747 6748 bool 6749 decl_readonly_section (const_tree decl, int reloc) 6750 { 6751 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc)); 6752 } 6753 6754 /* Select a section based on the above categorization. */ 6755 6756 section * 6757 default_elf_select_section (tree decl, int reloc, 6758 unsigned HOST_WIDE_INT align) 6759 { 6760 const char *sname; 6761 switch (categorize_decl_for_section (decl, reloc)) 6762 { 6763 case SECCAT_TEXT: 6764 /* We're not supposed to be called on FUNCTION_DECLs. */ 6765 gcc_unreachable (); 6766 case SECCAT_RODATA: 6767 return readonly_data_section; 6768 case SECCAT_RODATA_MERGE_STR: 6769 return mergeable_string_section (decl, align, 0); 6770 case SECCAT_RODATA_MERGE_STR_INIT: 6771 return mergeable_string_section (DECL_INITIAL (decl), align, 0); 6772 case SECCAT_RODATA_MERGE_CONST: 6773 return mergeable_constant_section (DECL_MODE (decl), align, 0); 6774 case SECCAT_SRODATA: 6775 sname = ".sdata2"; 6776 break; 6777 case SECCAT_DATA: 6778 return data_section; 6779 case SECCAT_DATA_REL: 6780 sname = ".data.rel"; 6781 break; 6782 case SECCAT_DATA_REL_LOCAL: 6783 sname = ".data.rel.local"; 6784 break; 6785 case SECCAT_DATA_REL_RO: 6786 sname = ".data.rel.ro"; 6787 break; 6788 case SECCAT_DATA_REL_RO_LOCAL: 6789 sname = ".data.rel.ro.local"; 6790 break; 6791 case SECCAT_SDATA: 6792 sname = ".sdata"; 6793 break; 6794 case SECCAT_TDATA: 6795 sname = ".tdata"; 6796 break; 6797 case SECCAT_BSS: 6798 if (bss_section) 6799 return bss_section; 6800 sname = ".bss"; 6801 break; 6802 case SECCAT_SBSS: 6803 sname = ".sbss"; 6804 break; 6805 case SECCAT_TBSS: 6806 sname = ".tbss"; 6807 break; 6808 default: 6809 gcc_unreachable (); 6810 } 6811 6812 return get_named_section (decl, sname, reloc); 6813 } 6814 6815 /* Construct a unique section name based on the decl name and the 6816 categorization performed above. */ 6817 6818 void 6819 default_unique_section (tree decl, int reloc) 6820 { 6821 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */ 6822 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP; 6823 const char *prefix, *name, *linkonce; 6824 char *string; 6825 tree id; 6826 6827 switch (categorize_decl_for_section (decl, reloc)) 6828 { 6829 case SECCAT_TEXT: 6830 prefix = one_only ? ".t" : ".text"; 6831 break; 6832 case SECCAT_RODATA: 6833 case SECCAT_RODATA_MERGE_STR: 6834 case SECCAT_RODATA_MERGE_STR_INIT: 6835 case SECCAT_RODATA_MERGE_CONST: 6836 prefix = one_only ? ".r" : ".rodata"; 6837 break; 6838 case SECCAT_SRODATA: 6839 prefix = one_only ? ".s2" : ".sdata2"; 6840 break; 6841 case SECCAT_DATA: 6842 prefix = one_only ? ".d" : ".data"; 6843 break; 6844 case SECCAT_DATA_REL: 6845 prefix = one_only ? ".d.rel" : ".data.rel"; 6846 break; 6847 case SECCAT_DATA_REL_LOCAL: 6848 prefix = one_only ? ".d.rel.local" : ".data.rel.local"; 6849 break; 6850 case SECCAT_DATA_REL_RO: 6851 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro"; 6852 break; 6853 case SECCAT_DATA_REL_RO_LOCAL: 6854 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local"; 6855 break; 6856 case SECCAT_SDATA: 6857 prefix = one_only ? ".s" : ".sdata"; 6858 break; 6859 case SECCAT_BSS: 6860 prefix = one_only ? ".b" : ".bss"; 6861 break; 6862 case SECCAT_SBSS: 6863 prefix = one_only ? ".sb" : ".sbss"; 6864 break; 6865 case SECCAT_TDATA: 6866 prefix = one_only ? ".td" : ".tdata"; 6867 break; 6868 case SECCAT_TBSS: 6869 prefix = one_only ? ".tb" : ".tbss"; 6870 break; 6871 default: 6872 gcc_unreachable (); 6873 } 6874 6875 id = DECL_ASSEMBLER_NAME (decl); 6876 ultimate_transparent_alias_target (&id); 6877 name = IDENTIFIER_POINTER (id); 6878 name = targetm.strip_name_encoding (name); 6879 6880 /* If we're using one_only, then there needs to be a .gnu.linkonce 6881 prefix to the section name. */ 6882 linkonce = one_only ? ".gnu.linkonce" : ""; 6883 6884 string = ACONCAT ((linkonce, prefix, ".", name, NULL)); 6885 6886 set_decl_section_name (decl, string); 6887 } 6888 6889 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */ 6890 6891 static int 6892 compute_reloc_for_rtx_1 (const_rtx x) 6893 { 6894 switch (GET_CODE (x)) 6895 { 6896 case SYMBOL_REF: 6897 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2; 6898 case LABEL_REF: 6899 return 1; 6900 default: 6901 return 0; 6902 } 6903 } 6904 6905 /* Like compute_reloc_for_constant, except for an RTX. The return value 6906 is a mask for which bit 1 indicates a global relocation, and bit 0 6907 indicates a local relocation. */ 6908 6909 static int 6910 compute_reloc_for_rtx (const_rtx x) 6911 { 6912 switch (GET_CODE (x)) 6913 { 6914 case SYMBOL_REF: 6915 case LABEL_REF: 6916 return compute_reloc_for_rtx_1 (x); 6917 6918 case CONST: 6919 { 6920 int reloc = 0; 6921 subrtx_iterator::array_type array; 6922 FOR_EACH_SUBRTX (iter, array, x, ALL) 6923 reloc |= compute_reloc_for_rtx_1 (*iter); 6924 return reloc; 6925 } 6926 6927 default: 6928 return 0; 6929 } 6930 } 6931 6932 section * 6933 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED, 6934 rtx x, 6935 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED) 6936 { 6937 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ()) 6938 return data_section; 6939 else 6940 return readonly_data_section; 6941 } 6942 6943 section * 6944 default_elf_select_rtx_section (machine_mode mode, rtx x, 6945 unsigned HOST_WIDE_INT align) 6946 { 6947 int reloc = compute_reloc_for_rtx (x); 6948 6949 /* ??? Handle small data here somehow. */ 6950 6951 if (reloc & targetm.asm_out.reloc_rw_mask ()) 6952 { 6953 if (reloc == 1) 6954 return get_named_section (NULL, ".data.rel.ro.local", 1); 6955 else 6956 return get_named_section (NULL, ".data.rel.ro", 3); 6957 } 6958 6959 return mergeable_constant_section (mode, align, 0); 6960 } 6961 6962 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */ 6963 6964 void 6965 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED) 6966 { 6967 rtx symbol; 6968 int flags; 6969 6970 /* Careful not to prod global register variables. */ 6971 if (!MEM_P (rtl)) 6972 return; 6973 symbol = XEXP (rtl, 0); 6974 if (GET_CODE (symbol) != SYMBOL_REF) 6975 return; 6976 6977 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO; 6978 if (TREE_CODE (decl) == FUNCTION_DECL) 6979 flags |= SYMBOL_FLAG_FUNCTION; 6980 if (targetm.binds_local_p (decl)) 6981 flags |= SYMBOL_FLAG_LOCAL; 6982 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl)) 6983 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT; 6984 else if (targetm.in_small_data_p (decl)) 6985 flags |= SYMBOL_FLAG_SMALL; 6986 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without 6987 being PUBLIC, the thing *must* be defined in this translation unit. 6988 Prevent this buglet from being propagated into rtl code as well. */ 6989 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl)) 6990 flags |= SYMBOL_FLAG_EXTERNAL; 6991 6992 SYMBOL_REF_FLAGS (symbol) = flags; 6993 } 6994 6995 /* By default, we do nothing for encode_section_info, so we need not 6996 do anything but discard the '*' marker. */ 6997 6998 const char * 6999 default_strip_name_encoding (const char *str) 7000 { 7001 return str + (*str == '*'); 7002 } 7003 7004 #ifdef ASM_OUTPUT_DEF 7005 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the 7006 anchor relative to ".", the current section position. */ 7007 7008 void 7009 default_asm_output_anchor (rtx symbol) 7010 { 7011 char buffer[100]; 7012 7013 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC, 7014 SYMBOL_REF_BLOCK_OFFSET (symbol)); 7015 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer); 7016 } 7017 #endif 7018 7019 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */ 7020 7021 bool 7022 default_use_anchors_for_symbol_p (const_rtx symbol) 7023 { 7024 tree decl; 7025 section *sect = SYMBOL_REF_BLOCK (symbol)->sect; 7026 7027 /* This function should only be called with non-zero SYMBOL_REF_BLOCK, 7028 furthermore get_block_for_section should not create object blocks 7029 for mergeable sections. */ 7030 gcc_checking_assert (sect && !(sect->common.flags & SECTION_MERGE)); 7031 7032 /* Don't use anchors for small data sections. The small data register 7033 acts as an anchor for such sections. */ 7034 if (sect->common.flags & SECTION_SMALL) 7035 return false; 7036 7037 decl = SYMBOL_REF_DECL (symbol); 7038 if (decl && DECL_P (decl)) 7039 { 7040 /* Don't use section anchors for decls that might be defined or 7041 usurped by other modules. */ 7042 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl)) 7043 return false; 7044 7045 /* Don't use section anchors for decls that will be placed in a 7046 small data section. */ 7047 /* ??? Ideally, this check would be redundant with the SECTION_SMALL 7048 one above. The problem is that we only use SECTION_SMALL for 7049 sections that should be marked as small in the section directive. */ 7050 if (targetm.in_small_data_p (decl)) 7051 return false; 7052 7053 /* Don't use section anchors for decls that won't fit inside a single 7054 anchor range to reduce the amount of instructions required to refer 7055 to the entire declaration. */ 7056 if (DECL_SIZE_UNIT (decl) == NULL_TREE 7057 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)) 7058 || (tree_to_uhwi (DECL_SIZE_UNIT (decl)) 7059 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset)) 7060 return false; 7061 7062 } 7063 return true; 7064 } 7065 7066 /* Return true when RESOLUTION indicate that symbol will be bound to the 7067 definition provided by current .o file. */ 7068 7069 static bool 7070 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution) 7071 { 7072 return (resolution == LDPR_PREVAILING_DEF 7073 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP 7074 || resolution == LDPR_PREVAILING_DEF_IRONLY); 7075 } 7076 7077 /* Return true when RESOLUTION indicate that symbol will be bound locally 7078 within current executable or DSO. */ 7079 7080 static bool 7081 resolution_local_p (enum ld_plugin_symbol_resolution resolution) 7082 { 7083 return (resolution == LDPR_PREVAILING_DEF 7084 || resolution == LDPR_PREVAILING_DEF_IRONLY 7085 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP 7086 || resolution == LDPR_PREEMPTED_REG 7087 || resolution == LDPR_PREEMPTED_IR 7088 || resolution == LDPR_RESOLVED_IR 7089 || resolution == LDPR_RESOLVED_EXEC); 7090 } 7091 7092 /* COMMON_LOCAL_P is true means that the linker can guarantee that an 7093 uninitialized common symbol in the executable will still be defined 7094 (through COPY relocation) in the executable. */ 7095 7096 bool 7097 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate, 7098 bool extern_protected_data, bool common_local_p) 7099 { 7100 /* A non-decl is an entry in the constant pool. */ 7101 if (!DECL_P (exp)) 7102 return true; 7103 7104 /* Weakrefs may not bind locally, even though the weakref itself is always 7105 static and therefore local. Similarly, the resolver for ifunc functions 7106 might resolve to a non-local function. 7107 FIXME: We can resolve the weakref case more curefuly by looking at the 7108 weakref alias. */ 7109 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp)) 7110 || (TREE_CODE (exp) == FUNCTION_DECL 7111 && cgraph_node::get (exp) 7112 && cgraph_node::get (exp)->ifunc_resolver)) 7113 return false; 7114 7115 /* Static variables are always local. */ 7116 if (! TREE_PUBLIC (exp)) 7117 return true; 7118 7119 /* With resolution file in hand, take look into resolutions. 7120 We can't just return true for resolved_locally symbols, 7121 because dynamic linking might overwrite symbols 7122 in shared libraries. */ 7123 bool resolved_locally = false; 7124 7125 bool uninited_common = (DECL_COMMON (exp) 7126 && (DECL_INITIAL (exp) == NULL 7127 || (!in_lto_p 7128 && DECL_INITIAL (exp) == error_mark_node))); 7129 7130 /* A non-external variable is defined locally only if it isn't 7131 uninitialized COMMON variable or common_local_p is true. */ 7132 bool defined_locally = (!DECL_EXTERNAL (exp) 7133 && (!uninited_common || common_local_p)); 7134 if (symtab_node *node = symtab_node::get (exp)) 7135 { 7136 if (node->in_other_partition) 7137 defined_locally = true; 7138 if (node->can_be_discarded_p ()) 7139 ; 7140 else if (resolution_to_local_definition_p (node->resolution)) 7141 defined_locally = resolved_locally = true; 7142 else if (resolution_local_p (node->resolution)) 7143 resolved_locally = true; 7144 } 7145 if (defined_locally && weak_dominate && !shlib) 7146 resolved_locally = true; 7147 7148 /* Undefined weak symbols are never defined locally. */ 7149 if (DECL_WEAK (exp) && !defined_locally) 7150 return false; 7151 7152 /* A symbol is local if the user has said explicitly that it will be, 7153 or if we have a definition for the symbol. We cannot infer visibility 7154 for undefined symbols. */ 7155 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT 7156 && (TREE_CODE (exp) == FUNCTION_DECL 7157 || !extern_protected_data 7158 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED) 7159 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally)) 7160 return true; 7161 7162 /* If PIC, then assume that any global name can be overridden by 7163 symbols resolved from other modules. */ 7164 if (shlib) 7165 return false; 7166 7167 /* Variables defined outside this object might not be local. */ 7168 if (DECL_EXTERNAL (exp) && !resolved_locally) 7169 return false; 7170 7171 /* Non-dominant weak symbols are not defined locally. */ 7172 if (DECL_WEAK (exp) && !resolved_locally) 7173 return false; 7174 7175 /* Uninitialized COMMON variable may be unified with symbols 7176 resolved from other modules. */ 7177 if (uninited_common && !resolved_locally) 7178 return false; 7179 7180 /* Otherwise we're left with initialized (or non-common) global data 7181 which is of necessity defined locally. */ 7182 return true; 7183 } 7184 7185 /* Assume ELF-ish defaults, since that's pretty much the most liberal 7186 wrt cross-module name binding. */ 7187 7188 bool 7189 default_binds_local_p (const_tree exp) 7190 { 7191 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false); 7192 } 7193 7194 /* Similar to default_binds_local_p, but common symbol may be local and 7195 extern protected data is non-local. */ 7196 7197 bool 7198 default_binds_local_p_2 (const_tree exp) 7199 { 7200 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true, 7201 !flag_pic); 7202 } 7203 7204 bool 7205 default_binds_local_p_1 (const_tree exp, int shlib) 7206 { 7207 return default_binds_local_p_3 (exp, shlib != 0, false, false, false); 7208 } 7209 7210 /* Return true when references to DECL must bind to current definition in 7211 final executable. 7212 7213 The condition is usually equivalent to whether the function binds to the 7214 current module (shared library or executable), that is to binds_local_p. 7215 We use this fact to avoid need for another target hook and implement 7216 the logic using binds_local_p and just special cases where 7217 decl_binds_to_current_def_p is stronger than binds_local_p. In particular 7218 the weak definitions (that can be overwritten at linktime by other 7219 definition from different object file) and when resolution info is available 7220 we simply use the knowledge passed to us by linker plugin. */ 7221 bool 7222 decl_binds_to_current_def_p (const_tree decl) 7223 { 7224 gcc_assert (DECL_P (decl)); 7225 if (!targetm.binds_local_p (decl)) 7226 return false; 7227 if (!TREE_PUBLIC (decl)) 7228 return true; 7229 7230 /* When resolution is available, just use it. */ 7231 if (symtab_node *node = symtab_node::get (decl)) 7232 { 7233 if (node->resolution != LDPR_UNKNOWN 7234 && !node->can_be_discarded_p ()) 7235 return resolution_to_local_definition_p (node->resolution); 7236 } 7237 7238 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks 7239 binds locally but still can be overwritten), DECL_COMMON (can be merged 7240 with a non-common definition somewhere in the same module) or 7241 DECL_EXTERNAL. 7242 This rely on fact that binds_local_p behave as decl_replaceable_p 7243 for all other declaration types. */ 7244 if (DECL_WEAK (decl)) 7245 return false; 7246 if (DECL_COMMON (decl) 7247 && (DECL_INITIAL (decl) == NULL 7248 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node))) 7249 return false; 7250 if (DECL_EXTERNAL (decl)) 7251 return false; 7252 return true; 7253 } 7254 7255 /* A replaceable function or variable is one which may be replaced 7256 at link-time with an entirely different definition, provided that the 7257 replacement has the same type. For example, functions declared 7258 with __attribute__((weak)) on most systems are replaceable. 7259 7260 COMDAT functions are not replaceable, since all definitions of the 7261 function must be equivalent. It is important that COMDAT functions 7262 not be treated as replaceable so that use of C++ template 7263 instantiations is not penalized. */ 7264 7265 bool 7266 decl_replaceable_p (tree decl) 7267 { 7268 gcc_assert (DECL_P (decl)); 7269 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl)) 7270 return false; 7271 if (!flag_semantic_interposition 7272 && !DECL_WEAK (decl)) 7273 return false; 7274 return !decl_binds_to_current_def_p (decl); 7275 } 7276 7277 /* Default function to output code that will globalize a label. A 7278 target must define GLOBAL_ASM_OP or provide its own function to 7279 globalize a label. */ 7280 #ifdef GLOBAL_ASM_OP 7281 void 7282 default_globalize_label (FILE * stream, const char *name) 7283 { 7284 fputs (GLOBAL_ASM_OP, stream); 7285 assemble_name (stream, name); 7286 putc ('\n', stream); 7287 } 7288 #endif /* GLOBAL_ASM_OP */ 7289 7290 /* Default function to output code that will globalize a declaration. */ 7291 void 7292 default_globalize_decl_name (FILE * stream, tree decl) 7293 { 7294 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 7295 targetm.asm_out.globalize_label (stream, name); 7296 } 7297 7298 /* Default function to output a label for unwind information. The 7299 default is to do nothing. A target that needs nonlocal labels for 7300 unwind information must provide its own function to do this. */ 7301 void 7302 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED, 7303 tree decl ATTRIBUTE_UNUSED, 7304 int for_eh ATTRIBUTE_UNUSED, 7305 int empty ATTRIBUTE_UNUSED) 7306 { 7307 } 7308 7309 /* Default function to output a label to divide up the exception table. 7310 The default is to do nothing. A target that needs/wants to divide 7311 up the table must provide it's own function to do this. */ 7312 void 7313 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED) 7314 { 7315 } 7316 7317 /* This is how to output an internal numbered label where PREFIX is 7318 the class of label and LABELNO is the number within the class. */ 7319 7320 void 7321 default_generate_internal_label (char *buf, const char *prefix, 7322 unsigned long labelno) 7323 { 7324 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno); 7325 } 7326 7327 /* This is how to output an internal numbered label where PREFIX is 7328 the class of label and LABELNO is the number within the class. */ 7329 7330 void 7331 default_internal_label (FILE *stream, const char *prefix, 7332 unsigned long labelno) 7333 { 7334 char *const buf = (char *) alloca (40 + strlen (prefix)); 7335 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno); 7336 ASM_OUTPUT_INTERNAL_LABEL (stream, buf); 7337 } 7338 7339 7340 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */ 7341 7342 void 7343 default_asm_declare_constant_name (FILE *file, const char *name, 7344 const_tree exp ATTRIBUTE_UNUSED, 7345 HOST_WIDE_INT size ATTRIBUTE_UNUSED) 7346 { 7347 assemble_label (file, name); 7348 } 7349 7350 /* This is the default behavior at the beginning of a file. It's 7351 controlled by two other target-hook toggles. */ 7352 void 7353 default_file_start (void) 7354 { 7355 if (targetm.asm_file_start_app_off 7356 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm)) 7357 fputs (ASM_APP_OFF, asm_out_file); 7358 7359 if (targetm.asm_file_start_file_directive) 7360 { 7361 /* LTO produced units have no meaningful main_input_filename. */ 7362 if (in_lto_p) 7363 output_file_directive (asm_out_file, "<artificial>"); 7364 else 7365 output_file_directive (asm_out_file, main_input_filename); 7366 } 7367 } 7368 7369 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END 7370 which emits a special section directive used to indicate whether or 7371 not this object file needs an executable stack. This is primarily 7372 a GNU extension to ELF but could be used on other targets. */ 7373 7374 int trampolines_created; 7375 7376 void 7377 file_end_indicate_exec_stack (void) 7378 { 7379 unsigned int flags = SECTION_DEBUG; 7380 if (trampolines_created) 7381 flags |= SECTION_CODE; 7382 7383 switch_to_section (get_section (".note.GNU-stack", flags, NULL)); 7384 } 7385 7386 /* Emit a special section directive to indicate that this object file 7387 was compiled with -fsplit-stack. This is used to let the linker 7388 detect calls between split-stack code and non-split-stack code, so 7389 that it can modify the split-stack code to allocate a sufficiently 7390 large stack. We emit another special section if there are any 7391 functions in this file which have the no_split_stack attribute, to 7392 prevent the linker from warning about being unable to convert the 7393 functions if they call non-split-stack code. */ 7394 7395 void 7396 file_end_indicate_split_stack (void) 7397 { 7398 if (flag_split_stack) 7399 { 7400 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG, 7401 NULL)); 7402 if (saw_no_split_stack) 7403 switch_to_section (get_section (".note.GNU-no-split-stack", 7404 SECTION_DEBUG, NULL)); 7405 } 7406 } 7407 7408 /* Output DIRECTIVE (a C string) followed by a newline. This is used as 7409 a get_unnamed_section callback. */ 7410 7411 void 7412 output_section_asm_op (const void *directive) 7413 { 7414 fprintf (asm_out_file, "%s\n", (const char *) directive); 7415 } 7416 7417 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if 7418 the current section is NEW_SECTION. */ 7419 7420 void 7421 switch_to_section (section *new_section) 7422 { 7423 if (in_section == new_section) 7424 return; 7425 7426 if (new_section->common.flags & SECTION_FORGET) 7427 in_section = NULL; 7428 else 7429 in_section = new_section; 7430 7431 switch (SECTION_STYLE (new_section)) 7432 { 7433 case SECTION_NAMED: 7434 targetm.asm_out.named_section (new_section->named.name, 7435 new_section->named.common.flags, 7436 new_section->named.decl); 7437 break; 7438 7439 case SECTION_UNNAMED: 7440 new_section->unnamed.callback (new_section->unnamed.data); 7441 break; 7442 7443 case SECTION_NOSWITCH: 7444 gcc_unreachable (); 7445 break; 7446 } 7447 7448 new_section->common.flags |= SECTION_DECLARED; 7449 } 7450 7451 /* If block symbol SYMBOL has not yet been assigned an offset, place 7452 it at the end of its block. */ 7453 7454 void 7455 place_block_symbol (rtx symbol) 7456 { 7457 unsigned HOST_WIDE_INT size, mask, offset; 7458 struct constant_descriptor_rtx *desc; 7459 unsigned int alignment; 7460 struct object_block *block; 7461 tree decl; 7462 7463 gcc_assert (SYMBOL_REF_BLOCK (symbol)); 7464 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0) 7465 return; 7466 7467 /* Work out the symbol's size and alignment. */ 7468 if (CONSTANT_POOL_ADDRESS_P (symbol)) 7469 { 7470 desc = SYMBOL_REF_CONSTANT (symbol); 7471 alignment = desc->align; 7472 size = GET_MODE_SIZE (desc->mode); 7473 } 7474 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol)) 7475 { 7476 decl = SYMBOL_REF_DECL (symbol); 7477 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl)); 7478 alignment = DECL_ALIGN (decl); 7479 size = get_constant_size (DECL_INITIAL (decl)); 7480 if ((flag_sanitize & SANITIZE_ADDRESS) 7481 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST 7482 && asan_protect_global (DECL_INITIAL (decl))) 7483 { 7484 size += asan_red_zone_size (size); 7485 alignment = MAX (alignment, 7486 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT); 7487 } 7488 } 7489 else 7490 { 7491 struct symtab_node *snode; 7492 decl = SYMBOL_REF_DECL (symbol); 7493 7494 snode = symtab_node::get (decl); 7495 if (snode->alias) 7496 { 7497 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl); 7498 7499 gcc_assert (MEM_P (target) 7500 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF 7501 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0))); 7502 target = XEXP (target, 0); 7503 place_block_symbol (target); 7504 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target); 7505 return; 7506 } 7507 alignment = get_variable_align (decl); 7508 size = tree_to_uhwi (DECL_SIZE_UNIT (decl)); 7509 if ((flag_sanitize & SANITIZE_ADDRESS) 7510 && asan_protect_global (decl)) 7511 { 7512 size += asan_red_zone_size (size); 7513 alignment = MAX (alignment, 7514 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT); 7515 } 7516 } 7517 7518 /* Calculate the object's offset from the start of the block. */ 7519 block = SYMBOL_REF_BLOCK (symbol); 7520 mask = alignment / BITS_PER_UNIT - 1; 7521 offset = (block->size + mask) & ~mask; 7522 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset; 7523 7524 /* Record the block's new alignment and size. */ 7525 block->alignment = MAX (block->alignment, alignment); 7526 block->size = offset + size; 7527 7528 vec_safe_push (block->objects, symbol); 7529 } 7530 7531 /* Return the anchor that should be used to address byte offset OFFSET 7532 from the first object in BLOCK. MODEL is the TLS model used 7533 to access it. */ 7534 7535 rtx 7536 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset, 7537 enum tls_model model) 7538 { 7539 char label[100]; 7540 unsigned int begin, middle, end; 7541 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta; 7542 rtx anchor; 7543 7544 /* Work out the anchor's offset. Use an offset of 0 for the first 7545 anchor so that we don't pessimize the case where we take the address 7546 of a variable at the beginning of the block. This is particularly 7547 useful when a block has only one variable assigned to it. 7548 7549 We try to place anchors RANGE bytes apart, so there can then be 7550 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of 7551 a ptr_mode offset. With some target settings, the lowest such 7552 anchor might be out of range for the lowest ptr_mode offset; 7553 likewise the highest anchor for the highest offset. Use anchors 7554 at the extreme ends of the ptr_mode range in such cases. 7555 7556 All arithmetic uses unsigned integers in order to avoid 7557 signed overflow. */ 7558 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset; 7559 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset; 7560 range = max_offset - min_offset + 1; 7561 if (range == 0) 7562 offset = 0; 7563 else 7564 { 7565 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1); 7566 if (offset < 0) 7567 { 7568 delta = -(unsigned HOST_WIDE_INT) offset + max_offset; 7569 delta -= delta % range; 7570 if (delta > bias) 7571 delta = bias; 7572 offset = (HOST_WIDE_INT) (-delta); 7573 } 7574 else 7575 { 7576 delta = (unsigned HOST_WIDE_INT) offset - min_offset; 7577 delta -= delta % range; 7578 if (delta > bias - 1) 7579 delta = bias - 1; 7580 offset = (HOST_WIDE_INT) delta; 7581 } 7582 } 7583 7584 /* Do a binary search to see if there's already an anchor we can use. 7585 Set BEGIN to the new anchor's index if not. */ 7586 begin = 0; 7587 end = vec_safe_length (block->anchors); 7588 while (begin != end) 7589 { 7590 middle = (end + begin) / 2; 7591 anchor = (*block->anchors)[middle]; 7592 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset) 7593 end = middle; 7594 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset) 7595 begin = middle + 1; 7596 else if (SYMBOL_REF_TLS_MODEL (anchor) > model) 7597 end = middle; 7598 else if (SYMBOL_REF_TLS_MODEL (anchor) < model) 7599 begin = middle + 1; 7600 else 7601 return anchor; 7602 } 7603 7604 /* Create a new anchor with a unique label. */ 7605 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++); 7606 anchor = create_block_symbol (ggc_strdup (label), block, offset); 7607 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR; 7608 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT; 7609 7610 /* Insert it at index BEGIN. */ 7611 vec_safe_insert (block->anchors, begin, anchor); 7612 return anchor; 7613 } 7614 7615 /* Output the objects in BLOCK. */ 7616 7617 static void 7618 output_object_block (struct object_block *block) 7619 { 7620 struct constant_descriptor_rtx *desc; 7621 unsigned int i; 7622 HOST_WIDE_INT offset; 7623 tree decl; 7624 rtx symbol; 7625 7626 if (!block->objects) 7627 return; 7628 7629 /* Switch to the section and make sure that the first byte is 7630 suitably aligned. */ 7631 /* Special case VTV comdat sections similar to assemble_variable. */ 7632 if (SECTION_STYLE (block->sect) == SECTION_NAMED 7633 && block->sect->named.name 7634 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0)) 7635 handle_vtv_comdat_section (block->sect, block->sect->named.decl); 7636 else 7637 switch_to_section (block->sect); 7638 7639 gcc_checking_assert (!(block->sect->common.flags & SECTION_MERGE)); 7640 assemble_align (block->alignment); 7641 7642 /* Define the values of all anchors relative to the current section 7643 position. */ 7644 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol) 7645 targetm.asm_out.output_anchor (symbol); 7646 7647 /* Output the objects themselves. */ 7648 offset = 0; 7649 FOR_EACH_VEC_ELT (*block->objects, i, symbol) 7650 { 7651 /* Move to the object's offset, padding with zeros if necessary. */ 7652 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset); 7653 offset = SYMBOL_REF_BLOCK_OFFSET (symbol); 7654 if (CONSTANT_POOL_ADDRESS_P (symbol)) 7655 { 7656 desc = SYMBOL_REF_CONSTANT (symbol); 7657 /* Pass 1 for align as we have already laid out everything in the block. 7658 So aligning shouldn't be necessary. */ 7659 output_constant_pool_1 (desc, 1); 7660 offset += GET_MODE_SIZE (desc->mode); 7661 } 7662 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol)) 7663 { 7664 HOST_WIDE_INT size; 7665 decl = SYMBOL_REF_DECL (symbol); 7666 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0), 7667 DECL_ALIGN (decl), false); 7668 7669 size = get_constant_size (DECL_INITIAL (decl)); 7670 offset += size; 7671 if ((flag_sanitize & SANITIZE_ADDRESS) 7672 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST 7673 && asan_protect_global (DECL_INITIAL (decl))) 7674 { 7675 size = asan_red_zone_size (size); 7676 assemble_zeros (size); 7677 offset += size; 7678 } 7679 } 7680 else 7681 { 7682 HOST_WIDE_INT size; 7683 decl = SYMBOL_REF_DECL (symbol); 7684 assemble_variable_contents (decl, XSTR (symbol, 0), false, false); 7685 size = tree_to_uhwi (DECL_SIZE_UNIT (decl)); 7686 offset += size; 7687 if ((flag_sanitize & SANITIZE_ADDRESS) 7688 && asan_protect_global (decl)) 7689 { 7690 size = asan_red_zone_size (size); 7691 assemble_zeros (size); 7692 offset += size; 7693 } 7694 } 7695 } 7696 } 7697 7698 /* A callback for qsort to compare object_blocks. */ 7699 7700 static int 7701 output_object_block_compare (const void *x, const void *y) 7702 { 7703 object_block *p1 = *(object_block * const*)x; 7704 object_block *p2 = *(object_block * const*)y; 7705 7706 if (p1->sect->common.flags & SECTION_NAMED 7707 && !(p2->sect->common.flags & SECTION_NAMED)) 7708 return 1; 7709 7710 if (!(p1->sect->common.flags & SECTION_NAMED) 7711 && p2->sect->common.flags & SECTION_NAMED) 7712 return -1; 7713 7714 if (p1->sect->common.flags & SECTION_NAMED 7715 && p2->sect->common.flags & SECTION_NAMED) 7716 return strcmp (p1->sect->named.name, p2->sect->named.name); 7717 7718 unsigned f1 = p1->sect->common.flags; 7719 unsigned f2 = p2->sect->common.flags; 7720 if (f1 == f2) 7721 return 0; 7722 return f1 < f2 ? -1 : 1; 7723 } 7724 7725 /* Output the definitions of all object_blocks. */ 7726 7727 void 7728 output_object_blocks (void) 7729 { 7730 vec<object_block *, va_heap> v; 7731 v.create (object_block_htab->elements ()); 7732 object_block *obj; 7733 hash_table<object_block_hasher>::iterator hi; 7734 7735 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi) 7736 v.quick_push (obj); 7737 7738 /* Sort them in order to output them in a deterministic manner, 7739 otherwise we may get .rodata sections in different orders with 7740 and without -g. */ 7741 v.qsort (output_object_block_compare); 7742 unsigned i; 7743 FOR_EACH_VEC_ELT (v, i, obj) 7744 output_object_block (obj); 7745 7746 v.release (); 7747 } 7748 7749 /* This function provides a possible implementation of the 7750 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered 7751 by -frecord-gcc-switches it creates a new mergeable, string section in the 7752 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which 7753 contains the switches in ASCII format. 7754 7755 FIXME: This code does not correctly handle double quote characters 7756 that appear inside strings, (it strips them rather than preserving them). 7757 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL 7758 characters - instead it treats them as sub-string separators. Since 7759 we want to emit NUL strings terminators into the object file we have to use 7760 ASM_OUTPUT_SKIP. */ 7761 7762 int 7763 elf_record_gcc_switches (print_switch_type type, const char * name) 7764 { 7765 switch (type) 7766 { 7767 case SWITCH_TYPE_PASSED: 7768 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name)); 7769 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U); 7770 break; 7771 7772 case SWITCH_TYPE_DESCRIPTIVE: 7773 if (name == NULL) 7774 { 7775 /* Distinguish between invocations where name is NULL. */ 7776 static bool started = false; 7777 7778 if (!started) 7779 { 7780 section * sec; 7781 7782 sec = get_section (targetm.asm_out.record_gcc_switches_section, 7783 SECTION_DEBUG 7784 | SECTION_MERGE 7785 | SECTION_STRINGS 7786 | (SECTION_ENTSIZE & 1), 7787 NULL); 7788 switch_to_section (sec); 7789 started = true; 7790 } 7791 } 7792 7793 default: 7794 break; 7795 } 7796 7797 /* The return value is currently ignored by the caller, but must be 0. 7798 For -fverbose-asm the return value would be the number of characters 7799 emitted into the assembler file. */ 7800 return 0; 7801 } 7802 7803 /* Emit text to declare externally defined symbols. It is needed to 7804 properly support non-default visibility. */ 7805 void 7806 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED, 7807 tree decl, 7808 const char *name ATTRIBUTE_UNUSED) 7809 { 7810 /* We output the name if and only if TREE_SYMBOL_REFERENCED is 7811 set in order to avoid putting out names that are never really 7812 used. Always output visibility specified in the source. */ 7813 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)) 7814 && (DECL_VISIBILITY_SPECIFIED (decl) 7815 || targetm.binds_local_p (decl))) 7816 maybe_assemble_visibility (decl); 7817 } 7818 7819 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */ 7820 7821 void 7822 default_asm_output_source_filename (FILE *file, const char *name) 7823 { 7824 #ifdef ASM_OUTPUT_SOURCE_FILENAME 7825 ASM_OUTPUT_SOURCE_FILENAME (file, name); 7826 #else 7827 fprintf (file, "\t.file\t"); 7828 output_quoted_string (file, name); 7829 putc ('\n', file); 7830 #endif 7831 } 7832 7833 /* Output a file name in the form wanted by System V. */ 7834 7835 void 7836 output_file_directive (FILE *asm_file, const char *input_name) 7837 { 7838 int len; 7839 const char *na; 7840 7841 if (input_name == NULL) 7842 input_name = "<stdin>"; 7843 else 7844 input_name = remap_debug_filename (input_name); 7845 7846 len = strlen (input_name); 7847 na = input_name + len; 7848 7849 /* NA gets INPUT_NAME sans directory names. */ 7850 while (na > input_name) 7851 { 7852 if (IS_DIR_SEPARATOR (na[-1])) 7853 break; 7854 na--; 7855 } 7856 7857 targetm.asm_out.output_source_filename (asm_file, na); 7858 } 7859 7860 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression 7861 EXP. */ 7862 rtx 7863 make_debug_expr_from_rtl (const_rtx exp) 7864 { 7865 tree ddecl = make_node (DEBUG_EXPR_DECL), type; 7866 machine_mode mode = GET_MODE (exp); 7867 rtx dval; 7868 7869 DECL_ARTIFICIAL (ddecl) = 1; 7870 if (REG_P (exp) && REG_EXPR (exp)) 7871 type = TREE_TYPE (REG_EXPR (exp)); 7872 else if (MEM_P (exp) && MEM_EXPR (exp)) 7873 type = TREE_TYPE (MEM_EXPR (exp)); 7874 else 7875 type = NULL_TREE; 7876 if (type && TYPE_MODE (type) == mode) 7877 TREE_TYPE (ddecl) = type; 7878 else 7879 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1); 7880 SET_DECL_MODE (ddecl, mode); 7881 dval = gen_rtx_DEBUG_EXPR (mode); 7882 DEBUG_EXPR_TREE_DECL (dval) = ddecl; 7883 SET_DECL_RTL (ddecl, dval); 7884 return dval; 7885 } 7886 7887 #ifdef ELF_ASCII_ESCAPES 7888 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */ 7889 7890 void 7891 default_elf_asm_output_limited_string (FILE *f, const char *s) 7892 { 7893 int escape; 7894 unsigned char c; 7895 7896 fputs (STRING_ASM_OP, f); 7897 putc ('"', f); 7898 while (*s != '\0') 7899 { 7900 c = *s; 7901 escape = ELF_ASCII_ESCAPES[c]; 7902 switch (escape) 7903 { 7904 case 0: 7905 putc (c, f); 7906 break; 7907 case 1: 7908 putc ('\\', f); 7909 putc ('0'+((c>>6)&7), f); 7910 putc ('0'+((c>>3)&7), f); 7911 putc ('0'+(c&7), f); 7912 break; 7913 default: 7914 putc ('\\', f); 7915 putc (escape, f); 7916 break; 7917 } 7918 s++; 7919 } 7920 putc ('\"', f); 7921 putc ('\n', f); 7922 } 7923 7924 /* Default ASM_OUTPUT_ASCII for ELF targets. */ 7925 7926 void 7927 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len) 7928 { 7929 const char *limit = s + len; 7930 const char *last_null = NULL; 7931 unsigned bytes_in_chunk = 0; 7932 unsigned char c; 7933 int escape; 7934 7935 for (; s < limit; s++) 7936 { 7937 const char *p; 7938 7939 if (bytes_in_chunk >= 60) 7940 { 7941 putc ('\"', f); 7942 putc ('\n', f); 7943 bytes_in_chunk = 0; 7944 } 7945 7946 if (s > last_null) 7947 { 7948 for (p = s; p < limit && *p != '\0'; p++) 7949 continue; 7950 last_null = p; 7951 } 7952 else 7953 p = last_null; 7954 7955 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT) 7956 { 7957 if (bytes_in_chunk > 0) 7958 { 7959 putc ('\"', f); 7960 putc ('\n', f); 7961 bytes_in_chunk = 0; 7962 } 7963 7964 default_elf_asm_output_limited_string (f, s); 7965 s = p; 7966 } 7967 else 7968 { 7969 if (bytes_in_chunk == 0) 7970 fputs (ASCII_DATA_ASM_OP "\"", f); 7971 7972 c = *s; 7973 escape = ELF_ASCII_ESCAPES[c]; 7974 switch (escape) 7975 { 7976 case 0: 7977 putc (c, f); 7978 bytes_in_chunk++; 7979 break; 7980 case 1: 7981 putc ('\\', f); 7982 putc ('0'+((c>>6)&7), f); 7983 putc ('0'+((c>>3)&7), f); 7984 putc ('0'+(c&7), f); 7985 bytes_in_chunk += 4; 7986 break; 7987 default: 7988 putc ('\\', f); 7989 putc (escape, f); 7990 bytes_in_chunk += 2; 7991 break; 7992 } 7993 7994 } 7995 } 7996 7997 if (bytes_in_chunk > 0) 7998 { 7999 putc ('\"', f); 8000 putc ('\n', f); 8001 } 8002 } 8003 #endif 8004 8005 static GTY(()) section *elf_init_array_section; 8006 static GTY(()) section *elf_fini_array_section; 8007 8008 static section * 8009 get_elf_initfini_array_priority_section (int priority, 8010 bool constructor_p) 8011 { 8012 section *sec; 8013 if (priority != DEFAULT_INIT_PRIORITY) 8014 { 8015 char buf[18]; 8016 sprintf (buf, "%s.%.5u", 8017 constructor_p ? ".init_array" : ".fini_array", 8018 priority); 8019 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE); 8020 } 8021 else 8022 { 8023 if (constructor_p) 8024 { 8025 if (elf_init_array_section == NULL) 8026 elf_init_array_section 8027 = get_section (".init_array", 8028 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE); 8029 sec = elf_init_array_section; 8030 } 8031 else 8032 { 8033 if (elf_fini_array_section == NULL) 8034 elf_fini_array_section 8035 = get_section (".fini_array", 8036 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE); 8037 sec = elf_fini_array_section; 8038 } 8039 } 8040 return sec; 8041 } 8042 8043 /* Use .init_array section for constructors. */ 8044 8045 void 8046 default_elf_init_array_asm_out_constructor (rtx symbol, int priority) 8047 { 8048 section *sec = get_elf_initfini_array_priority_section (priority, 8049 true); 8050 assemble_addr_to_section (symbol, sec); 8051 } 8052 8053 /* Use .fini_array section for destructors. */ 8054 8055 void 8056 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority) 8057 { 8058 section *sec = get_elf_initfini_array_priority_section (priority, 8059 false); 8060 assemble_addr_to_section (symbol, sec); 8061 } 8062 8063 /* Default TARGET_ASM_OUTPUT_IDENT hook. 8064 8065 This is a bit of a cheat. The real default is a no-op, but this 8066 hook is the default for all targets with a .ident directive. */ 8067 8068 void 8069 default_asm_output_ident_directive (const char *ident_str) 8070 { 8071 const char *ident_asm_op = "\t.ident\t"; 8072 8073 /* If we are still in the front end, do not write out the string 8074 to asm_out_file. Instead, add a fake top-level asm statement. 8075 This allows the front ends to use this hook without actually 8076 writing to asm_out_file, to handle #ident or Pragma Ident. */ 8077 if (symtab->state == PARSING) 8078 { 8079 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL)); 8080 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf)); 8081 } 8082 else 8083 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str); 8084 } 8085 8086 8087 /* This function ensures that vtable_map variables are not only 8088 in the comdat section, but that each variable has its own unique 8089 comdat name. Without this the variables end up in the same section 8090 with a single comdat name. 8091 8092 FIXME: resolve_unique_section needs to deal better with 8093 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once 8094 that is fixed, this if-else statement can be replaced with 8095 a single call to "switch_to_section (sect)". */ 8096 8097 static void 8098 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED) 8099 { 8100 #if defined (OBJECT_FORMAT_ELF) 8101 targetm.asm_out.named_section (sect->named.name, 8102 sect->named.common.flags 8103 | SECTION_LINKONCE, 8104 DECL_NAME (decl)); 8105 in_section = sect; 8106 #else 8107 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here. 8108 Therefore the following check is used. 8109 In case a the target is PE or COFF a comdat group section 8110 is created, e.g. .vtable_map_vars$foo. The linker places 8111 everything in .vtable_map_vars at the end. 8112 8113 A fix could be made in 8114 gcc/config/i386/winnt.c: i386_pe_unique_section. */ 8115 if (TARGET_PECOFF) 8116 { 8117 char *name; 8118 8119 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE) 8120 name = ACONCAT ((sect->named.name, "$", 8121 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL)); 8122 else 8123 name = ACONCAT ((sect->named.name, "$", 8124 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))), 8125 NULL)); 8126 8127 targetm.asm_out.named_section (name, 8128 sect->named.common.flags 8129 | SECTION_LINKONCE, 8130 DECL_NAME (decl)); 8131 in_section = sect; 8132 } 8133 else 8134 switch_to_section (sect); 8135 #endif 8136 } 8137 8138 #include "gt-varasm.h" 8139