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