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