varasm.c revision 117395
1/* Output variables, constants and external declarations, for GNU compiler. 2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 3 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. 4 5This file is part of GCC. 6 7GCC is free software; you can redistribute it and/or modify it under 8the terms of the GNU General Public License as published by the Free 9Software Foundation; either version 2, or (at your option) any later 10version. 11 12GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13WARRANTY; without even the implied warranty of MERCHANTABILITY or 14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15for more details. 16 17You should have received a copy of the GNU General Public License 18along with GCC; see the file COPYING. If not, write to the Free 19Software Foundation, 59 Temple Place - Suite 330, Boston, MA 2002111-1307, USA. */ 21 22 23/* This file handles generation of all the assembler code 24 *except* the instructions of a function. 25 This includes declarations of variables and their initial values. 26 27 We also output the assembler code for constants stored in memory 28 and are responsible for combining constants with the same value. */ 29 30#include "config.h" 31#include "system.h" 32#include "rtl.h" 33#include "tree.h" 34#include "flags.h" 35#include "function.h" 36#include "expr.h" 37#include "hard-reg-set.h" 38#include "regs.h" 39#include "real.h" 40#include "output.h" 41#include "toplev.h" 42#include "hashtab.h" 43#include "c-pragma.h" 44#include "c-tree.h" 45#include "ggc.h" 46#include "langhooks.h" 47#include "tm_p.h" 48#include "debug.h" 49#include "target.h" 50 51#ifdef XCOFF_DEBUGGING_INFO 52#include "xcoffout.h" /* Needed for external data 53 declarations for e.g. AIX 4.x. */ 54#endif 55 56#ifndef TRAMPOLINE_ALIGNMENT 57#define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY 58#endif 59 60#ifndef ASM_STABS_OP 61#define ASM_STABS_OP "\t.stabs\t" 62#endif 63 64/* The (assembler) name of the first globally-visible object output. */ 65const char *first_global_object_name; 66const char *weak_global_object_name; 67 68struct addr_const; 69struct constant_descriptor_rtx; 70struct rtx_const; 71struct pool_constant; 72 73#define MAX_RTX_HASH_TABLE 61 74 75struct varasm_status GTY(()) 76{ 77 /* Hash facility for making memory-constants 78 from constant rtl-expressions. It is used on RISC machines 79 where immediate integer arguments and constant addresses are restricted 80 so that such constants must be stored in memory. 81 82 This pool of constants is reinitialized for each function 83 so each function gets its own constants-pool that comes right before 84 it. */ 85 struct constant_descriptor_rtx ** GTY ((length ("MAX_RTX_HASH_TABLE"))) 86 x_const_rtx_hash_table; 87 struct pool_constant ** GTY ((length ("MAX_RTX_HASH_TABLE"))) 88 x_const_rtx_sym_hash_table; 89 90 /* Pointers to first and last constant in pool. */ 91 struct pool_constant *x_first_pool; 92 struct pool_constant *x_last_pool; 93 94 /* Current offset in constant pool (does not include any machine-specific 95 header). */ 96 HOST_WIDE_INT x_pool_offset; 97}; 98 99#define const_rtx_hash_table (cfun->varasm->x_const_rtx_hash_table) 100#define const_rtx_sym_hash_table (cfun->varasm->x_const_rtx_sym_hash_table) 101#define first_pool (cfun->varasm->x_first_pool) 102#define last_pool (cfun->varasm->x_last_pool) 103#define pool_offset (cfun->varasm->x_pool_offset) 104 105/* Number for making the label on the next 106 constant that is stored in memory. */ 107 108int const_labelno; 109 110/* Number for making the label on the next 111 static variable internal to a function. */ 112 113int var_labelno; 114 115/* Carry information from ASM_DECLARE_OBJECT_NAME 116 to ASM_FINISH_DECLARE_OBJECT. */ 117 118int size_directive_output; 119 120/* The last decl for which assemble_variable was called, 121 if it did ASM_DECLARE_OBJECT_NAME. 122 If the last call to assemble_variable didn't do that, 123 this holds 0. */ 124 125tree last_assemble_variable_decl; 126 127/* RTX_UNCHANGING_P in a MEM can mean it is stored into, for initialization. 128 So giving constant the alias set for the type will allow such 129 initializations to appear to conflict with the load of the constant. We 130 avoid this by giving all constants an alias set for just constants. 131 Since there will be no stores to that alias set, nothing will ever 132 conflict with them. */ 133 134static HOST_WIDE_INT const_alias_set; 135 136static const char *strip_reg_name PARAMS ((const char *)); 137static int contains_pointers_p PARAMS ((tree)); 138static void decode_addr_const PARAMS ((tree, struct addr_const *)); 139static unsigned int const_hash PARAMS ((tree)); 140static unsigned int const_hash_1 PARAMS ((tree)); 141static int compare_constant PARAMS ((tree, tree)); 142static tree copy_constant PARAMS ((tree)); 143static void output_constant_def_contents PARAMS ((tree, int, int)); 144static void decode_rtx_const PARAMS ((enum machine_mode, rtx, 145 struct rtx_const *)); 146static unsigned int const_hash_rtx PARAMS ((enum machine_mode, rtx)); 147static int compare_constant_rtx 148 PARAMS ((enum machine_mode, rtx, struct constant_descriptor_rtx *)); 149static struct constant_descriptor_rtx * record_constant_rtx 150 PARAMS ((enum machine_mode, rtx)); 151static struct pool_constant *find_pool_constant PARAMS ((struct function *, rtx)); 152static void mark_constant_pool PARAMS ((void)); 153static void mark_constants PARAMS ((rtx)); 154static int mark_constant PARAMS ((rtx *current_rtx, void *data)); 155static int output_addressed_constants PARAMS ((tree)); 156static void output_after_function_constants PARAMS ((void)); 157static unsigned HOST_WIDE_INT array_size_for_constructor PARAMS ((tree)); 158static unsigned min_align PARAMS ((unsigned, unsigned)); 159static void output_constructor PARAMS ((tree, HOST_WIDE_INT, 160 unsigned int)); 161static void globalize_decl PARAMS ((tree)); 162static void maybe_assemble_visibility PARAMS ((tree)); 163static int in_named_entry_eq PARAMS ((const PTR, const PTR)); 164static hashval_t in_named_entry_hash PARAMS ((const PTR)); 165#ifdef ASM_OUTPUT_BSS 166static void asm_output_bss PARAMS ((FILE *, tree, const char *, int, int)); 167#endif 168#ifdef BSS_SECTION_ASM_OP 169#ifdef ASM_OUTPUT_ALIGNED_BSS 170static void asm_output_aligned_bss PARAMS ((FILE *, tree, const char *, 171 int, int)); 172#endif 173#endif /* BSS_SECTION_ASM_OP */ 174static hashval_t const_str_htab_hash PARAMS ((const void *x)); 175static int const_str_htab_eq PARAMS ((const void *x, const void *y)); 176static bool asm_emit_uninitialised PARAMS ((tree, const char*, int, int)); 177static void resolve_unique_section PARAMS ((tree, int, int)); 178static void mark_weak PARAMS ((tree)); 179 180static enum in_section { no_section, in_text, in_data, in_named 181#ifdef BSS_SECTION_ASM_OP 182 , in_bss 183#endif 184#ifdef CTORS_SECTION_ASM_OP 185 , in_ctors 186#endif 187#ifdef DTORS_SECTION_ASM_OP 188 , in_dtors 189#endif 190#ifdef READONLY_DATA_SECTION_ASM_OP 191 , in_readonly_data 192#endif 193#ifdef EXTRA_SECTIONS 194 , EXTRA_SECTIONS 195#endif 196} in_section = no_section; 197 198/* Return a nonzero value if DECL has a section attribute. */ 199#ifndef IN_NAMED_SECTION 200#define IN_NAMED_SECTION(DECL) \ 201 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \ 202 && DECL_SECTION_NAME (DECL) != NULL_TREE) 203#endif 204 205/* Text of section name when in_section == in_named. */ 206static const char *in_named_name; 207 208/* Hash table of flags that have been used for a particular named section. */ 209 210struct in_named_entry 211{ 212 const char *name; 213 unsigned int flags; 214 bool declared; 215}; 216 217static htab_t in_named_htab; 218 219/* Define functions like text_section for any extra sections. */ 220#ifdef EXTRA_SECTION_FUNCTIONS 221EXTRA_SECTION_FUNCTIONS 222#endif 223 224/* Tell assembler to switch to text section. */ 225 226void 227text_section () 228{ 229 if (in_section != in_text) 230 { 231 in_section = in_text; 232#ifdef TEXT_SECTION 233 TEXT_SECTION (); 234#else 235 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP); 236#endif 237 } 238} 239 240/* Tell assembler to switch to data section. */ 241 242void 243data_section () 244{ 245 if (in_section != in_data) 246 { 247 in_section = in_data; 248 if (flag_shared_data) 249 { 250#ifdef SHARED_SECTION_ASM_OP 251 fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP); 252#else 253 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); 254#endif 255 } 256 else 257 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); 258 } 259} 260 261/* Tell assembler to ALWAYS switch to data section, in case 262 it's not sure where it is. */ 263 264void 265force_data_section () 266{ 267 in_section = no_section; 268 data_section (); 269} 270 271/* Tell assembler to switch to read-only data section. This is normally 272 the text section. */ 273 274void 275readonly_data_section () 276{ 277#ifdef READONLY_DATA_SECTION 278 READONLY_DATA_SECTION (); /* Note this can call data_section. */ 279#else 280#ifdef READONLY_DATA_SECTION_ASM_OP 281 if (in_section != in_readonly_data) 282 { 283 in_section = in_readonly_data; 284 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file); 285 fputc ('\n', asm_out_file); 286 } 287#else 288 text_section (); 289#endif 290#endif 291} 292 293/* Determine if we're in the text section. */ 294 295int 296in_text_section () 297{ 298 return in_section == in_text; 299} 300 301/* Determine if we're in the data section. */ 302 303int 304in_data_section () 305{ 306 return in_section == in_data; 307} 308 309/* Helper routines for maintaining in_named_htab. */ 310 311static int 312in_named_entry_eq (p1, p2) 313 const PTR p1; 314 const PTR p2; 315{ 316 const struct in_named_entry *old = p1; 317 const char *new = p2; 318 319 return strcmp (old->name, new) == 0; 320} 321 322static hashval_t 323in_named_entry_hash (p) 324 const PTR p; 325{ 326 const struct in_named_entry *old = p; 327 return htab_hash_string (old->name); 328} 329 330/* If SECTION has been seen before as a named section, return the flags 331 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid 332 set of flags for a section to have, so 0 does not mean that the section 333 has not been seen. */ 334 335unsigned int 336get_named_section_flags (section) 337 const char *section; 338{ 339 struct in_named_entry **slot; 340 341 slot = (struct in_named_entry **) 342 htab_find_slot_with_hash (in_named_htab, section, 343 htab_hash_string (section), NO_INSERT); 344 345 return slot ? (*slot)->flags : 0; 346} 347 348/* Returns true if the section has been declared before. Sets internal 349 flag on this section in in_named_hash so subsequent calls on this 350 section will return false. */ 351 352bool 353named_section_first_declaration (name) 354 const char *name; 355{ 356 struct in_named_entry **slot; 357 358 slot = (struct in_named_entry **) 359 htab_find_slot_with_hash (in_named_htab, name, 360 htab_hash_string (name), NO_INSERT); 361 if (! (*slot)->declared) 362 { 363 (*slot)->declared = true; 364 return true; 365 } 366 else 367 { 368 return false; 369 } 370} 371 372 373/* Record FLAGS for SECTION. If SECTION was previously recorded with a 374 different set of flags, return false. */ 375 376bool 377set_named_section_flags (section, flags) 378 const char *section; 379 unsigned int flags; 380{ 381 struct in_named_entry **slot, *entry; 382 383 slot = (struct in_named_entry **) 384 htab_find_slot_with_hash (in_named_htab, section, 385 htab_hash_string (section), INSERT); 386 entry = *slot; 387 388 if (!entry) 389 { 390 entry = (struct in_named_entry *) xmalloc (sizeof (*entry)); 391 *slot = entry; 392 entry->name = ggc_strdup (section); 393 entry->flags = flags; 394 entry->declared = false; 395 } 396 else if (entry->flags != flags) 397 return false; 398 399 return true; 400} 401 402/* Tell assembler to change to section NAME with attributes FLAGS. */ 403 404void 405named_section_flags (name, flags) 406 const char *name; 407 unsigned int flags; 408{ 409 if (in_section != in_named || strcmp (name, in_named_name) != 0) 410 { 411 if (! set_named_section_flags (name, flags)) 412 abort (); 413 414 (*targetm.asm_out.named_section) (name, flags); 415 416 if (flags & SECTION_FORGET) 417 in_section = no_section; 418 else 419 { 420 in_named_name = ggc_strdup (name); 421 in_section = in_named; 422 } 423 } 424} 425 426/* Tell assembler to change to section NAME for DECL. 427 If DECL is NULL, just switch to section NAME. 428 If NAME is NULL, get the name from DECL. 429 If RELOC is 1, the initializer for DECL contains relocs. */ 430 431void 432named_section (decl, name, reloc) 433 tree decl; 434 const char *name; 435 int reloc; 436{ 437 unsigned int flags; 438 439 if (decl != NULL_TREE && !DECL_P (decl)) 440 abort (); 441 if (name == NULL) 442 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl)); 443 444 flags = (* targetm.section_type_flags) (decl, name, reloc); 445 446 /* Sanity check user variables for flag changes. Non-user 447 section flag changes will abort in named_section_flags. 448 However, don't complain if SECTION_OVERRIDE is set. 449 We trust that the setter knows that it is safe to ignore 450 the default flags for this decl. */ 451 if (decl && ! set_named_section_flags (name, flags)) 452 { 453 flags = get_named_section_flags (name); 454 if ((flags & SECTION_OVERRIDE) == 0) 455 error_with_decl (decl, "%s causes a section type conflict"); 456 } 457 458 named_section_flags (name, flags); 459} 460 461/* If required, set DECL_SECTION_NAME to a unique name. */ 462 463static void 464resolve_unique_section (decl, reloc, flag_function_or_data_sections) 465 tree decl; 466 int reloc ATTRIBUTE_UNUSED; 467 int flag_function_or_data_sections; 468{ 469 if (DECL_SECTION_NAME (decl) == NULL_TREE 470 && targetm.have_named_sections 471 && (flag_function_or_data_sections 472 || DECL_ONE_ONLY (decl))) 473 (*targetm.asm_out.unique_section) (decl, reloc); 474} 475 476#ifdef BSS_SECTION_ASM_OP 477 478/* Tell the assembler to switch to the bss section. */ 479 480void 481bss_section () 482{ 483 if (in_section != in_bss) 484 { 485#ifdef SHARED_BSS_SECTION_ASM_OP 486 if (flag_shared_data) 487 fprintf (asm_out_file, "%s\n", SHARED_BSS_SECTION_ASM_OP); 488 else 489#endif 490 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP); 491 492 in_section = in_bss; 493 } 494} 495 496#ifdef ASM_OUTPUT_BSS 497 498/* Utility function for ASM_OUTPUT_BSS for targets to use if 499 they don't support alignments in .bss. 500 ??? It is believed that this function will work in most cases so such 501 support is localized here. */ 502 503static void 504asm_output_bss (file, decl, name, size, rounded) 505 FILE *file; 506 tree decl ATTRIBUTE_UNUSED; 507 const char *name; 508 int size ATTRIBUTE_UNUSED, rounded; 509{ 510 (*targetm.asm_out.globalize_label) (file, name); 511 bss_section (); 512#ifdef ASM_DECLARE_OBJECT_NAME 513 last_assemble_variable_decl = decl; 514 ASM_DECLARE_OBJECT_NAME (file, name, decl); 515#else 516 /* Standard thing is just output label for the object. */ 517 ASM_OUTPUT_LABEL (file, name); 518#endif /* ASM_DECLARE_OBJECT_NAME */ 519 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1); 520} 521 522#endif 523 524#ifdef ASM_OUTPUT_ALIGNED_BSS 525 526/* Utility function for targets to use in implementing 527 ASM_OUTPUT_ALIGNED_BSS. 528 ??? It is believed that this function will work in most cases so such 529 support is localized here. */ 530 531static void 532asm_output_aligned_bss (file, decl, name, size, align) 533 FILE *file; 534 tree decl ATTRIBUTE_UNUSED; 535 const char *name; 536 int size, align; 537{ 538 bss_section (); 539 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); 540#ifdef ASM_DECLARE_OBJECT_NAME 541 last_assemble_variable_decl = decl; 542 ASM_DECLARE_OBJECT_NAME (file, name, decl); 543#else 544 /* Standard thing is just output label for the object. */ 545 ASM_OUTPUT_LABEL (file, name); 546#endif /* ASM_DECLARE_OBJECT_NAME */ 547 ASM_OUTPUT_SKIP (file, size ? size : 1); 548} 549 550#endif 551 552#endif /* BSS_SECTION_ASM_OP */ 553 554/* Switch to the section for function DECL. 555 556 If DECL is NULL_TREE, switch to the text section. 557 ??? It's not clear that we will ever be passed NULL_TREE, but it's 558 safer to handle it. */ 559 560void 561function_section (decl) 562 tree decl; 563{ 564 if (decl != NULL_TREE 565 && DECL_SECTION_NAME (decl) != NULL_TREE) 566 named_section (decl, (char *) 0, 0); 567 else 568 text_section (); 569} 570 571/* Switch to section for variable DECL. RELOC is the same as the 572 argument to SELECT_SECTION. */ 573 574void 575variable_section (decl, reloc) 576 tree decl; 577 int reloc; 578{ 579 if (IN_NAMED_SECTION (decl)) 580 named_section (decl, NULL, reloc); 581 else 582 (*targetm.asm_out.select_section) (decl, reloc, DECL_ALIGN (decl)); 583} 584 585/* Tell assembler to switch to the section for string merging. */ 586 587void 588mergeable_string_section (decl, align, flags) 589 tree decl ATTRIBUTE_UNUSED; 590 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED; 591 unsigned int flags ATTRIBUTE_UNUSED; 592{ 593#ifdef HAVE_GAS_SHF_MERGE 594 if (flag_merge_constants 595 && TREE_CODE (decl) == STRING_CST 596 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 597 && align <= 256 598 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl))) 599 { 600 enum machine_mode mode; 601 unsigned int modesize; 602 const char *str; 603 int i, j, len, unit; 604 char name[30]; 605 606 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl))); 607 modesize = GET_MODE_BITSIZE (mode); 608 if (modesize >= 8 && modesize <= 256 609 && (modesize & (modesize - 1)) == 0) 610 { 611 if (align < modesize) 612 align = modesize; 613 614 str = TREE_STRING_POINTER (decl); 615 len = TREE_STRING_LENGTH (decl); 616 unit = GET_MODE_SIZE (mode); 617 618 /* Check for embedded NUL characters. */ 619 for (i = 0; i < len; i += unit) 620 { 621 for (j = 0; j < unit; j++) 622 if (str[i + j] != '\0') 623 break; 624 if (j == unit) 625 break; 626 } 627 if (i == len - unit) 628 { 629 sprintf (name, ".rodata.str%d.%d", modesize / 8, 630 (int) (align / 8)); 631 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS; 632 if (!i && modesize < align) 633 { 634 /* A "" string with requested alignment greater than 635 character size might cause a problem: 636 if some other string required even bigger 637 alignment than "", then linker might think the 638 "" is just part of padding after some other string 639 and not put it into the hash table initially. 640 But this means "" could have smaller alignment 641 than requested. */ 642#ifdef ASM_OUTPUT_SECTION_START 643 named_section_flags (name, flags); 644 ASM_OUTPUT_SECTION_START (asm_out_file); 645#else 646 readonly_data_section (); 647#endif 648 return; 649 } 650 651 named_section_flags (name, flags); 652 return; 653 } 654 } 655 } 656#endif 657 readonly_data_section (); 658} 659 660/* Tell assembler to switch to the section for constant merging. */ 661 662void 663mergeable_constant_section (mode, align, flags) 664 enum machine_mode mode ATTRIBUTE_UNUSED; 665 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED; 666 unsigned int flags ATTRIBUTE_UNUSED; 667{ 668#ifdef HAVE_GAS_SHF_MERGE 669 unsigned int modesize = GET_MODE_BITSIZE (mode); 670 671 if (flag_merge_constants 672 && mode != VOIDmode 673 && mode != BLKmode 674 && modesize <= align 675 && align >= 8 676 && align <= 256 677 && (align & (align - 1)) == 0) 678 { 679 char name[24]; 680 681 sprintf (name, ".rodata.cst%d", (int) (align / 8)); 682 flags |= (align / 8) | SECTION_MERGE; 683 named_section_flags (name, flags); 684 return; 685 } 686#endif 687 readonly_data_section (); 688} 689 690/* Given NAME, a putative register name, discard any customary prefixes. */ 691 692static const char * 693strip_reg_name (name) 694 const char *name; 695{ 696#ifdef REGISTER_PREFIX 697 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX))) 698 name += strlen (REGISTER_PREFIX); 699#endif 700 if (name[0] == '%' || name[0] == '#') 701 name++; 702 return name; 703} 704 705/* Decode an `asm' spec for a declaration as a register name. 706 Return the register number, or -1 if nothing specified, 707 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized, 708 or -3 if ASMSPEC is `cc' and is not recognized, 709 or -4 if ASMSPEC is `memory' and is not recognized. 710 Accept an exact spelling or a decimal number. 711 Prefixes such as % are optional. */ 712 713int 714decode_reg_name (asmspec) 715 const char *asmspec; 716{ 717 if (asmspec != 0) 718 { 719 int i; 720 721 /* Get rid of confusing prefixes. */ 722 asmspec = strip_reg_name (asmspec); 723 724 /* Allow a decimal number as a "register name". */ 725 for (i = strlen (asmspec) - 1; i >= 0; i--) 726 if (! ISDIGIT (asmspec[i])) 727 break; 728 if (asmspec[0] != 0 && i < 0) 729 { 730 i = atoi (asmspec); 731 if (i < FIRST_PSEUDO_REGISTER && i >= 0) 732 return i; 733 else 734 return -2; 735 } 736 737 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) 738 if (reg_names[i][0] 739 && ! strcmp (asmspec, strip_reg_name (reg_names[i]))) 740 return i; 741 742#ifdef ADDITIONAL_REGISTER_NAMES 743 { 744 static const struct { const char *const name; const int number; } table[] 745 = ADDITIONAL_REGISTER_NAMES; 746 747 for (i = 0; i < (int) ARRAY_SIZE (table); i++) 748 if (! strcmp (asmspec, table[i].name)) 749 return table[i].number; 750 } 751#endif /* ADDITIONAL_REGISTER_NAMES */ 752 753 if (!strcmp (asmspec, "memory")) 754 return -4; 755 756 if (!strcmp (asmspec, "cc")) 757 return -3; 758 759 return -2; 760 } 761 762 return -1; 763} 764 765/* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should 766 have static storage duration. In other words, it should not be an 767 automatic variable, including PARM_DECLs. 768 769 There is, however, one exception: this function handles variables 770 explicitly placed in a particular register by the user. 771 772 ASMSPEC, if not 0, is the string which the user specified as the 773 assembler symbol name. 774 775 This is never called for PARM_DECL nodes. */ 776 777void 778make_decl_rtl (decl, asmspec) 779 tree decl; 780 const char *asmspec; 781{ 782 int top_level = (DECL_CONTEXT (decl) == NULL_TREE); 783 const char *name = 0; 784 const char *new_name = 0; 785 int reg_number; 786 rtx x; 787 788 /* Check that we are not being given an automatic variable. */ 789 /* A weak alias has TREE_PUBLIC set but not the other bits. */ 790 if (TREE_CODE (decl) == PARM_DECL 791 || TREE_CODE (decl) == RESULT_DECL 792 || (TREE_CODE (decl) == VAR_DECL 793 && !TREE_STATIC (decl) 794 && !TREE_PUBLIC (decl) 795 && !DECL_EXTERNAL (decl) 796 && !DECL_REGISTER (decl))) 797 abort (); 798 /* And that we were not given a type or a label. */ 799 else if (TREE_CODE (decl) == TYPE_DECL 800 || TREE_CODE (decl) == LABEL_DECL) 801 abort (); 802 803 /* For a duplicate declaration, we can be called twice on the 804 same DECL node. Don't discard the RTL already made. */ 805 if (DECL_RTL_SET_P (decl)) 806 { 807 /* If the old RTL had the wrong mode, fix the mode. */ 808 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl)) 809 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl), 810 DECL_MODE (decl), 0)); 811 812 /* ??? Another way to do this would be to maintain a hashed 813 table of such critters. Instead of adding stuff to a DECL 814 to give certain attributes to it, we could use an external 815 hash map from DECL to set of attributes. */ 816 817 /* Let the target reassign the RTL if it wants. 818 This is necessary, for example, when one machine specific 819 decl attribute overrides another. */ 820 (* targetm.encode_section_info) (decl, false); 821 return; 822 } 823 824 new_name = name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 825 826 reg_number = decode_reg_name (asmspec); 827 if (reg_number == -2) 828 { 829 /* ASMSPEC is given, and not the name of a register. Mark the 830 name with a star so assemble_name won't munge it. */ 831 char *starred = alloca (strlen (asmspec) + 2); 832 starred[0] = '*'; 833 strcpy (starred + 1, asmspec); 834 new_name = starred; 835 } 836 837 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl)) 838 { 839 /* First detect errors in declaring global registers. */ 840 if (reg_number == -1) 841 error_with_decl (decl, "register name not specified for `%s'"); 842 else if (reg_number < 0) 843 error_with_decl (decl, "invalid register name for `%s'"); 844 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode) 845 error_with_decl (decl, 846 "data type of `%s' isn't suitable for a register"); 847 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl)))) 848 error_with_decl (decl, 849 "register specified for `%s' isn't suitable for data type"); 850 /* Now handle properly declared static register variables. */ 851 else 852 { 853 int nregs; 854 855 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl)) 856 { 857 DECL_INITIAL (decl) = 0; 858 error ("global register variable has initial value"); 859 } 860 if (TREE_THIS_VOLATILE (decl)) 861 warning ("volatile register variables don't work as you might wish"); 862 863 /* If the user specified one of the eliminables registers here, 864 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable 865 confused with that register and be eliminated. This usage is 866 somewhat suspect... */ 867 868 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number)); 869 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number; 870 REG_USERVAR_P (DECL_RTL (decl)) = 1; 871 872 if (TREE_STATIC (decl)) 873 { 874 /* Make this register global, so not usable for anything 875 else. */ 876#ifdef ASM_DECLARE_REGISTER_GLOBAL 877 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name); 878#endif 879 nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl)); 880 while (nregs > 0) 881 globalize_reg (reg_number + --nregs); 882 } 883 884 /* As a register variable, it has no section. */ 885 return; 886 } 887 } 888 889 /* Now handle ordinary static variables and functions (in memory). 890 Also handle vars declared register invalidly. */ 891 892 if (reg_number >= 0 || reg_number == -3) 893 error_with_decl (decl, 894 "register name given for non-register variable `%s'"); 895 896 /* Specifying a section attribute on a variable forces it into a 897 non-.bss section, and thus it cannot be common. */ 898 if (TREE_CODE (decl) == VAR_DECL 899 && DECL_SECTION_NAME (decl) != NULL_TREE 900 && DECL_INITIAL (decl) == NULL_TREE 901 && DECL_COMMON (decl)) 902 DECL_COMMON (decl) = 0; 903 904 /* Variables can't be both common and weak. */ 905 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl)) 906 DECL_COMMON (decl) = 0; 907 908 /* Can't use just the variable's own name for a variable 909 whose scope is less than the whole file, unless it's a member 910 of a local class (which will already be unambiguous). 911 Concatenate a distinguishing number. */ 912 if (!top_level && !TREE_PUBLIC (decl) 913 && ! (DECL_CONTEXT (decl) && TYPE_P (DECL_CONTEXT (decl))) 914 && asmspec == 0 915 && name == IDENTIFIER_POINTER (DECL_NAME (decl))) 916 { 917 char *label; 918 919 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno); 920 var_labelno++; 921 new_name = label; 922 } 923 924 if (name != new_name) 925 { 926 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (new_name)); 927 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 928 } 929 930 /* If this variable is to be treated as volatile, show its 931 tree node has side effects. */ 932 if ((flag_volatile_global && TREE_CODE (decl) == VAR_DECL 933 && TREE_PUBLIC (decl)) 934 || ((flag_volatile_static && TREE_CODE (decl) == VAR_DECL 935 && (TREE_PUBLIC (decl) || TREE_STATIC (decl))))) 936 TREE_SIDE_EFFECTS (decl) = 1; 937 938 x = gen_rtx_MEM (DECL_MODE (decl), gen_rtx_SYMBOL_REF (Pmode, name)); 939 SYMBOL_REF_WEAK (XEXP (x, 0)) = DECL_WEAK (decl); 940 if (TREE_CODE (decl) != FUNCTION_DECL) 941 set_mem_attributes (x, decl, 1); 942 SET_DECL_RTL (decl, x); 943 944 /* Optionally set flags or add text to the name to record information 945 such as that it is a function name. 946 If the name is changed, the macro ASM_OUTPUT_LABELREF 947 will have to know how to strip this information. */ 948 (* targetm.encode_section_info) (decl, true); 949} 950 951/* Make the rtl for variable VAR be volatile. 952 Use this only for static variables. */ 953 954void 955make_var_volatile (var) 956 tree var; 957{ 958 if (GET_CODE (DECL_RTL (var)) != MEM) 959 abort (); 960 961 MEM_VOLATILE_P (DECL_RTL (var)) = 1; 962} 963 964/* Output alignment directive to align for constant expression EXP. */ 965 966void 967assemble_constant_align (exp) 968 tree exp; 969{ 970 int align; 971 972 /* Align the location counter as required by EXP's data type. */ 973 align = TYPE_ALIGN (TREE_TYPE (exp)); 974#ifdef CONSTANT_ALIGNMENT 975 align = CONSTANT_ALIGNMENT (exp, align); 976#endif 977 978 if (align > BITS_PER_UNIT) 979 { 980 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 981 } 982} 983 984/* Output a string of literal assembler code 985 for an `asm' keyword used between functions. */ 986 987void 988assemble_asm (string) 989 tree string; 990{ 991 app_enable (); 992 993 if (TREE_CODE (string) == ADDR_EXPR) 994 string = TREE_OPERAND (string, 0); 995 996 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string)); 997} 998 999/* Record an element in the table of global destructors. SYMBOL is 1000 a SYMBOL_REF of the function to be called; PRIORITY is a number 1001 between 0 and MAX_INIT_PRIORITY. */ 1002 1003void 1004default_stabs_asm_out_destructor (symbol, priority) 1005 rtx symbol; 1006 int priority ATTRIBUTE_UNUSED; 1007{ 1008 /* Tell GNU LD that this is part of the static destructor set. 1009 This will work for any system that uses stabs, most usefully 1010 aout systems. */ 1011 fprintf (asm_out_file, "%s\"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP); 1012 assemble_name (asm_out_file, XSTR (symbol, 0)); 1013 fputc ('\n', asm_out_file); 1014} 1015 1016void 1017default_named_section_asm_out_destructor (symbol, priority) 1018 rtx symbol; 1019 int priority; 1020{ 1021 const char *section = ".dtors"; 1022 char buf[16]; 1023 1024 /* ??? This only works reliably with the GNU linker. */ 1025 if (priority != DEFAULT_INIT_PRIORITY) 1026 { 1027 sprintf (buf, ".dtors.%.5u", 1028 /* Invert the numbering so the linker puts us in the proper 1029 order; constructors are run from right to left, and the 1030 linker sorts in increasing order. */ 1031 MAX_INIT_PRIORITY - priority); 1032 section = buf; 1033 } 1034 1035 named_section_flags (section, SECTION_WRITE); 1036 assemble_align (POINTER_SIZE); 1037 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1); 1038} 1039 1040#ifdef DTORS_SECTION_ASM_OP 1041void 1042dtors_section () 1043{ 1044 if (in_section != in_dtors) 1045 { 1046 in_section = in_dtors; 1047 fputs (DTORS_SECTION_ASM_OP, asm_out_file); 1048 fputc ('\n', asm_out_file); 1049 } 1050} 1051 1052void 1053default_dtor_section_asm_out_destructor (symbol, priority) 1054 rtx symbol; 1055 int priority ATTRIBUTE_UNUSED; 1056{ 1057 dtors_section (); 1058 assemble_align (POINTER_SIZE); 1059 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1); 1060} 1061#endif 1062 1063/* Likewise for global constructors. */ 1064 1065void 1066default_stabs_asm_out_constructor (symbol, priority) 1067 rtx symbol; 1068 int priority ATTRIBUTE_UNUSED; 1069{ 1070 /* Tell GNU LD that this is part of the static destructor set. 1071 This will work for any system that uses stabs, most usefully 1072 aout systems. */ 1073 fprintf (asm_out_file, "%s\"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP); 1074 assemble_name (asm_out_file, XSTR (symbol, 0)); 1075 fputc ('\n', asm_out_file); 1076} 1077 1078void 1079default_named_section_asm_out_constructor (symbol, priority) 1080 rtx symbol; 1081 int priority; 1082{ 1083 const char *section = ".ctors"; 1084 char buf[16]; 1085 1086 /* ??? This only works reliably with the GNU linker. */ 1087 if (priority != DEFAULT_INIT_PRIORITY) 1088 { 1089 sprintf (buf, ".ctors.%.5u", 1090 /* Invert the numbering so the linker puts us in the proper 1091 order; constructors are run from right to left, and the 1092 linker sorts in increasing order. */ 1093 MAX_INIT_PRIORITY - priority); 1094 section = buf; 1095 } 1096 1097 named_section_flags (section, SECTION_WRITE); 1098 assemble_align (POINTER_SIZE); 1099 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1); 1100} 1101 1102#ifdef CTORS_SECTION_ASM_OP 1103void 1104ctors_section () 1105{ 1106 if (in_section != in_ctors) 1107 { 1108 in_section = in_ctors; 1109 fputs (CTORS_SECTION_ASM_OP, asm_out_file); 1110 fputc ('\n', asm_out_file); 1111 } 1112} 1113 1114void 1115default_ctor_section_asm_out_constructor (symbol, priority) 1116 rtx symbol; 1117 int priority ATTRIBUTE_UNUSED; 1118{ 1119 ctors_section (); 1120 assemble_align (POINTER_SIZE); 1121 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1); 1122} 1123#endif 1124 1125/* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with 1126 a nonzero value if the constant pool should be output before the 1127 start of the function, or a zero value if the pool should output 1128 after the end of the function. The default is to put it before the 1129 start. */ 1130 1131#ifndef CONSTANT_POOL_BEFORE_FUNCTION 1132#define CONSTANT_POOL_BEFORE_FUNCTION 1 1133#endif 1134 1135/* Output assembler code for the constant pool of a function and associated 1136 with defining the name of the function. DECL describes the function. 1137 NAME is the function's name. For the constant pool, we use the current 1138 constant pool data. */ 1139 1140void 1141assemble_start_function (decl, fnname) 1142 tree decl; 1143 const char *fnname; 1144{ 1145 int align; 1146 1147 /* The following code does not need preprocessing in the assembler. */ 1148 1149 app_disable (); 1150 1151 if (CONSTANT_POOL_BEFORE_FUNCTION) 1152 output_constant_pool (fnname, decl); 1153 1154 resolve_unique_section (decl, 0, flag_function_sections); 1155 function_section (decl); 1156 1157 /* Tell assembler to move to target machine's alignment for functions. */ 1158 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT); 1159 if (align < force_align_functions_log) 1160 align = force_align_functions_log; 1161 if (align > 0) 1162 { 1163 ASM_OUTPUT_ALIGN (asm_out_file, align); 1164 } 1165 1166 /* Handle a user-specified function alignment. 1167 Note that we still need to align to FUNCTION_BOUNDARY, as above, 1168 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */ 1169 if (align_functions_log > align 1170 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED) 1171 { 1172#ifdef ASM_OUTPUT_MAX_SKIP_ALIGN 1173 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, 1174 align_functions_log, align_functions - 1); 1175#else 1176 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log); 1177#endif 1178 } 1179 1180#ifdef ASM_OUTPUT_FUNCTION_PREFIX 1181 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname); 1182#endif 1183 1184 (*debug_hooks->begin_function) (decl); 1185 1186 /* Make function name accessible from other files, if appropriate. */ 1187 1188 if (TREE_PUBLIC (decl)) 1189 { 1190 if (! first_global_object_name) 1191 { 1192 const char *p; 1193 char *name; 1194 1195 p = (* targetm.strip_name_encoding) (fnname); 1196 name = xstrdup (p); 1197 1198 if (! DECL_WEAK (decl) && ! DECL_ONE_ONLY (decl)) 1199 first_global_object_name = name; 1200 else 1201 weak_global_object_name = name; 1202 } 1203 1204 globalize_decl (decl); 1205 1206 maybe_assemble_visibility (decl); 1207 } 1208 1209 /* Do any machine/system dependent processing of the function name */ 1210#ifdef ASM_DECLARE_FUNCTION_NAME 1211 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl); 1212#else 1213 /* Standard thing is just output label for the function. */ 1214 ASM_OUTPUT_LABEL (asm_out_file, fnname); 1215#endif /* ASM_DECLARE_FUNCTION_NAME */ 1216} 1217 1218/* Output assembler code associated with defining the size of the 1219 function. DECL describes the function. NAME is the function's name. */ 1220 1221void 1222assemble_end_function (decl, fnname) 1223 tree decl; 1224 const char *fnname; 1225{ 1226#ifdef ASM_DECLARE_FUNCTION_SIZE 1227 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl); 1228#endif 1229 if (! CONSTANT_POOL_BEFORE_FUNCTION) 1230 { 1231 output_constant_pool (fnname, decl); 1232 function_section (decl); /* need to switch back */ 1233 } 1234 1235 /* Output any constants which should appear after the function. */ 1236 output_after_function_constants (); 1237} 1238 1239/* Assemble code to leave SIZE bytes of zeros. */ 1240 1241void 1242assemble_zeros (size) 1243 int size; 1244{ 1245 /* Do no output if -fsyntax-only. */ 1246 if (flag_syntax_only) 1247 return; 1248 1249#ifdef ASM_NO_SKIP_IN_TEXT 1250 /* The `space' pseudo in the text section outputs nop insns rather than 0s, 1251 so we must output 0s explicitly in the text section. */ 1252 if (ASM_NO_SKIP_IN_TEXT && in_text_section ()) 1253 { 1254 int i; 1255 for (i = 0; i < size; i++) 1256 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1); 1257 } 1258 else 1259#endif 1260 if (size > 0) 1261 ASM_OUTPUT_SKIP (asm_out_file, size); 1262} 1263 1264/* Assemble an alignment pseudo op for an ALIGN-bit boundary. */ 1265 1266void 1267assemble_align (align) 1268 int align; 1269{ 1270 if (align > BITS_PER_UNIT) 1271 { 1272 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 1273 } 1274} 1275 1276/* Assemble a string constant with the specified C string as contents. */ 1277 1278void 1279assemble_string (p, size) 1280 const char *p; 1281 int size; 1282{ 1283 int pos = 0; 1284 int maximum = 2000; 1285 1286 /* If the string is very long, split it up. */ 1287 1288 while (pos < size) 1289 { 1290 int thissize = size - pos; 1291 if (thissize > maximum) 1292 thissize = maximum; 1293 1294 ASM_OUTPUT_ASCII (asm_out_file, p, thissize); 1295 1296 pos += thissize; 1297 p += thissize; 1298 } 1299} 1300 1301 1302#if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL 1303#define ASM_EMIT_LOCAL(decl, name, size, rounded) \ 1304 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl)) 1305#else 1306#if defined ASM_OUTPUT_ALIGNED_LOCAL 1307#define ASM_EMIT_LOCAL(decl, name, size, rounded) \ 1308 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl)) 1309#else 1310#define ASM_EMIT_LOCAL(decl, name, size, rounded) \ 1311 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded) 1312#endif 1313#endif 1314 1315#if defined ASM_OUTPUT_ALIGNED_BSS 1316#define ASM_EMIT_BSS(decl, name, size, rounded) \ 1317 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl)) 1318#else 1319#if defined ASM_OUTPUT_BSS 1320#define ASM_EMIT_BSS(decl, name, size, rounded) \ 1321 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded) 1322#else 1323#undef ASM_EMIT_BSS 1324#endif 1325#endif 1326 1327#if defined ASM_OUTPUT_ALIGNED_DECL_COMMON 1328#define ASM_EMIT_COMMON(decl, name, size, rounded) \ 1329 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl)) 1330#else 1331#if defined ASM_OUTPUT_ALIGNED_COMMON 1332#define ASM_EMIT_COMMON(decl, name, size, rounded) \ 1333 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl)) 1334#else 1335#define ASM_EMIT_COMMON(decl, name, size, rounded) \ 1336 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded) 1337#endif 1338#endif 1339 1340static bool 1341asm_emit_uninitialised (decl, name, size, rounded) 1342 tree decl; 1343 const char *name; 1344 int size ATTRIBUTE_UNUSED; 1345 int rounded ATTRIBUTE_UNUSED; 1346{ 1347 enum 1348 { 1349 asm_dest_common, 1350 asm_dest_bss, 1351 asm_dest_local 1352 } 1353 destination = asm_dest_local; 1354 1355 /* ??? We should handle .bss via select_section mechanisms rather than 1356 via special target hooks. That would eliminate this special case. */ 1357 if (TREE_PUBLIC (decl)) 1358 { 1359 if (!DECL_COMMON (decl)) 1360#ifdef ASM_EMIT_BSS 1361 destination = asm_dest_bss; 1362#else 1363 return false; 1364#endif 1365 else 1366 destination = asm_dest_common; 1367 } 1368 1369 if (destination == asm_dest_bss) 1370 globalize_decl (decl); 1371 resolve_unique_section (decl, 0, flag_data_sections); 1372 1373 if (flag_shared_data) 1374 { 1375 switch (destination) 1376 { 1377#ifdef ASM_OUTPUT_SHARED_BSS 1378 case asm_dest_bss: 1379 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded); 1380 return; 1381#endif 1382#ifdef ASM_OUTPUT_SHARED_COMMON 1383 case asm_dest_common: 1384 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded); 1385 return; 1386#endif 1387#ifdef ASM_OUTPUT_SHARED_LOCAL 1388 case asm_dest_local: 1389 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded); 1390 return; 1391#endif 1392 default: 1393 break; 1394 } 1395 } 1396 1397 switch (destination) 1398 { 1399#ifdef ASM_EMIT_BSS 1400 case asm_dest_bss: 1401 ASM_EMIT_BSS (decl, name, size, rounded); 1402 break; 1403#endif 1404 case asm_dest_common: 1405 ASM_EMIT_COMMON (decl, name, size, rounded); 1406 break; 1407 case asm_dest_local: 1408 ASM_EMIT_LOCAL (decl, name, size, rounded); 1409 break; 1410 default: 1411 abort (); 1412 } 1413 1414 return true; 1415} 1416 1417/* Assemble everything that is needed for a variable or function declaration. 1418 Not used for automatic variables, and not used for function definitions. 1419 Should not be called for variables of incomplete structure type. 1420 1421 TOP_LEVEL is nonzero if this variable has file scope. 1422 AT_END is nonzero if this is the special handling, at end of compilation, 1423 to define things that have had only tentative definitions. 1424 DONT_OUTPUT_DATA if nonzero means don't actually output the 1425 initial value (that will be done by the caller). */ 1426 1427void 1428assemble_variable (decl, top_level, at_end, dont_output_data) 1429 tree decl; 1430 int top_level ATTRIBUTE_UNUSED; 1431 int at_end ATTRIBUTE_UNUSED; 1432 int dont_output_data; 1433{ 1434 const char *name; 1435 unsigned int align; 1436 int reloc = 0; 1437 rtx decl_rtl; 1438 1439 last_assemble_variable_decl = 0; 1440 1441 /* Normally no need to say anything here for external references, 1442 since assemble_external is called by the language-specific code 1443 when a declaration is first seen. */ 1444 1445 if (DECL_EXTERNAL (decl)) 1446 return; 1447 1448 /* Output no assembler code for a function declaration. 1449 Only definitions of functions output anything. */ 1450 1451 if (TREE_CODE (decl) == FUNCTION_DECL) 1452 return; 1453 1454 /* Do nothing for global register variables. */ 1455 if (DECL_RTL_SET_P (decl) && GET_CODE (DECL_RTL (decl)) == REG) 1456 { 1457 TREE_ASM_WRITTEN (decl) = 1; 1458 return; 1459 } 1460 1461 /* If type was incomplete when the variable was declared, 1462 see if it is complete now. */ 1463 1464 if (DECL_SIZE (decl) == 0) 1465 layout_decl (decl, 0); 1466 1467 /* Still incomplete => don't allocate it; treat the tentative defn 1468 (which is what it must have been) as an `extern' reference. */ 1469 1470 if (!dont_output_data && DECL_SIZE (decl) == 0) 1471 { 1472 error_with_file_and_line (DECL_SOURCE_FILE (decl), 1473 DECL_SOURCE_LINE (decl), 1474 "storage size of `%s' isn't known", 1475 IDENTIFIER_POINTER (DECL_NAME (decl))); 1476 TREE_ASM_WRITTEN (decl) = 1; 1477 return; 1478 } 1479 1480 /* The first declaration of a variable that comes through this function 1481 decides whether it is global (in C, has external linkage) 1482 or local (in C, has internal linkage). So do nothing more 1483 if this function has already run. */ 1484 1485 if (TREE_ASM_WRITTEN (decl)) 1486 return; 1487 1488 /* Make sure targetm.encode_section_info is invoked before we set 1489 ASM_WRITTEN. */ 1490 decl_rtl = DECL_RTL (decl); 1491 1492 TREE_ASM_WRITTEN (decl) = 1; 1493 1494 /* Do no output if -fsyntax-only. */ 1495 if (flag_syntax_only) 1496 return; 1497 1498 app_disable (); 1499 1500 if (! dont_output_data 1501 && ! host_integerp (DECL_SIZE_UNIT (decl), 1)) 1502 { 1503 error_with_decl (decl, "size of variable `%s' is too large"); 1504 return; 1505 } 1506 1507 name = XSTR (XEXP (decl_rtl, 0), 0); 1508 if (TREE_PUBLIC (decl) && DECL_NAME (decl) 1509 && ! first_global_object_name 1510 && ! (DECL_COMMON (decl) && (DECL_INITIAL (decl) == 0 1511 || DECL_INITIAL (decl) == error_mark_node)) 1512 && ! DECL_WEAK (decl) 1513 && ! DECL_ONE_ONLY (decl)) 1514 { 1515 const char *p; 1516 char *xname; 1517 1518 p = (* targetm.strip_name_encoding) (name); 1519 xname = xstrdup (p); 1520 first_global_object_name = xname; 1521 } 1522 1523 /* Compute the alignment of this data. */ 1524 1525 align = DECL_ALIGN (decl); 1526 1527 /* In the case for initialing an array whose length isn't specified, 1528 where we have not yet been able to do the layout, 1529 figure out the proper alignment now. */ 1530 if (dont_output_data && DECL_SIZE (decl) == 0 1531 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE) 1532 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))); 1533 1534 /* Some object file formats have a maximum alignment which they support. 1535 In particular, a.out format supports a maximum alignment of 4. */ 1536#ifndef MAX_OFILE_ALIGNMENT 1537#define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT 1538#endif 1539 if (align > MAX_OFILE_ALIGNMENT) 1540 { 1541 warning_with_decl (decl, 1542 "alignment of `%s' is greater than maximum object file alignment. Using %d", 1543 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT); 1544 align = MAX_OFILE_ALIGNMENT; 1545 } 1546 1547 /* On some machines, it is good to increase alignment sometimes. */ 1548 if (! DECL_USER_ALIGN (decl)) 1549 { 1550#ifdef DATA_ALIGNMENT 1551 align = DATA_ALIGNMENT (TREE_TYPE (decl), align); 1552#endif 1553#ifdef CONSTANT_ALIGNMENT 1554 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node) 1555 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align); 1556#endif 1557 } 1558 1559 /* Reset the alignment in case we have made it tighter, so we can benefit 1560 from it in get_pointer_alignment. */ 1561 DECL_ALIGN (decl) = align; 1562 set_mem_align (decl_rtl, align); 1563 1564 if (TREE_PUBLIC (decl)) 1565 maybe_assemble_visibility (decl); 1566 1567 /* Output any data that we will need to use the address of. */ 1568 if (DECL_INITIAL (decl) == error_mark_node) 1569 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0; 1570 else if (DECL_INITIAL (decl)) 1571 reloc = output_addressed_constants (DECL_INITIAL (decl)); 1572 resolve_unique_section (decl, reloc, flag_data_sections); 1573 1574 /* Handle uninitialized definitions. */ 1575 1576 /* If the decl has been given an explicit section name, then it 1577 isn't common, and shouldn't be handled as such. */ 1578 if (DECL_SECTION_NAME (decl) || dont_output_data) 1579 ; 1580 /* We don't implement common thread-local data at present. */ 1581 else if (DECL_THREAD_LOCAL (decl)) 1582 { 1583 if (DECL_COMMON (decl)) 1584 sorry ("thread-local COMMON data not implemented"); 1585 } 1586 else if (DECL_INITIAL (decl) == 0 1587 || DECL_INITIAL (decl) == error_mark_node 1588 || (flag_zero_initialized_in_bss 1589 /* Leave constant zeroes in .rodata so they can be shared. */ 1590 && !TREE_READONLY (decl) 1591 && initializer_zerop (DECL_INITIAL (decl)))) 1592 { 1593 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1); 1594 unsigned HOST_WIDE_INT rounded = size; 1595 1596 /* Don't allocate zero bytes of common, 1597 since that means "undefined external" in the linker. */ 1598 if (size == 0) 1599 rounded = 1; 1600 1601 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 1602 so that each uninitialized object starts on such a boundary. */ 1603 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1; 1604 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 1605 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 1606 1607#if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS) 1608 if ((unsigned HOST_WIDE_INT) DECL_ALIGN (decl) / BITS_PER_UNIT > rounded) 1609 warning_with_decl 1610 (decl, "requested alignment for %s is greater than implemented alignment of %d",rounded); 1611#endif 1612 1613 /* If the target cannot output uninitialized but not common global data 1614 in .bss, then we have to use .data, so fall through. */ 1615 if (asm_emit_uninitialised (decl, name, size, rounded)) 1616 return; 1617 } 1618 1619 /* Handle initialized definitions. 1620 Also handle uninitialized global definitions if -fno-common and the 1621 target doesn't support ASM_OUTPUT_BSS. */ 1622 1623 /* First make the assembler name(s) global if appropriate. */ 1624 if (TREE_PUBLIC (decl) && DECL_NAME (decl)) 1625 globalize_decl (decl); 1626 1627 /* Switch to the appropriate section. */ 1628 variable_section (decl, reloc); 1629 1630 /* dbxout.c needs to know this. */ 1631 if (in_text_section ()) 1632 DECL_IN_TEXT_SECTION (decl) = 1; 1633 1634 /* Output the alignment of this data. */ 1635 if (align > BITS_PER_UNIT) 1636 { 1637 ASM_OUTPUT_ALIGN (asm_out_file, 1638 floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT)); 1639 } 1640 1641 /* Do any machine/system dependent processing of the object. */ 1642#ifdef ASM_DECLARE_OBJECT_NAME 1643 last_assemble_variable_decl = decl; 1644 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl); 1645#else 1646 /* Standard thing is just output label for the object. */ 1647 ASM_OUTPUT_LABEL (asm_out_file, name); 1648#endif /* ASM_DECLARE_OBJECT_NAME */ 1649 1650 if (!dont_output_data) 1651 { 1652 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node) 1653 /* Output the actual data. */ 1654 output_constant (DECL_INITIAL (decl), 1655 tree_low_cst (DECL_SIZE_UNIT (decl), 1), 1656 align); 1657 else 1658 /* Leave space for it. */ 1659 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1)); 1660 } 1661} 1662 1663/* Return 1 if type TYPE contains any pointers. */ 1664 1665static int 1666contains_pointers_p (type) 1667 tree type; 1668{ 1669 switch (TREE_CODE (type)) 1670 { 1671 case POINTER_TYPE: 1672 case REFERENCE_TYPE: 1673 /* I'm not sure whether OFFSET_TYPE needs this treatment, 1674 so I'll play safe and return 1. */ 1675 case OFFSET_TYPE: 1676 return 1; 1677 1678 case RECORD_TYPE: 1679 case UNION_TYPE: 1680 case QUAL_UNION_TYPE: 1681 { 1682 tree fields; 1683 /* For a type that has fields, see if the fields have pointers. */ 1684 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) 1685 if (TREE_CODE (fields) == FIELD_DECL 1686 && contains_pointers_p (TREE_TYPE (fields))) 1687 return 1; 1688 return 0; 1689 } 1690 1691 case ARRAY_TYPE: 1692 /* An array type contains pointers if its element type does. */ 1693 return contains_pointers_p (TREE_TYPE (type)); 1694 1695 default: 1696 return 0; 1697 } 1698} 1699 1700/* Output something to declare an external symbol to the assembler. 1701 (Most assemblers don't need this, so we normally output nothing.) 1702 Do nothing if DECL is not external. */ 1703 1704void 1705assemble_external (decl) 1706 tree decl ATTRIBUTE_UNUSED; 1707{ 1708 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the 1709 main body of this code is only rarely exercised. To provide some 1710 testing, on all platforms, we make sure that the ASM_OUT_FILE is 1711 open. If it's not, we should not be calling this function. */ 1712 if (!asm_out_file) 1713 abort (); 1714 1715#ifdef ASM_OUTPUT_EXTERNAL 1716 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl)) 1717 { 1718 rtx rtl = DECL_RTL (decl); 1719 1720 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF 1721 && ! SYMBOL_REF_USED (XEXP (rtl, 0))) 1722 { 1723 /* Some systems do require some output. */ 1724 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1; 1725 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0)); 1726 } 1727 } 1728#endif 1729} 1730 1731/* Similar, for calling a library function FUN. */ 1732 1733void 1734assemble_external_libcall (fun) 1735 rtx fun ATTRIBUTE_UNUSED; 1736{ 1737#ifdef ASM_OUTPUT_EXTERNAL_LIBCALL 1738 /* Declare library function name external when first used, if nec. */ 1739 if (! SYMBOL_REF_USED (fun)) 1740 { 1741 SYMBOL_REF_USED (fun) = 1; 1742 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun); 1743 } 1744#endif 1745} 1746 1747/* Assemble a label named NAME. */ 1748 1749void 1750assemble_label (name) 1751 const char *name; 1752{ 1753 ASM_OUTPUT_LABEL (asm_out_file, name); 1754} 1755 1756/* Output to FILE a reference to the assembler name of a C-level name NAME. 1757 If NAME starts with a *, the rest of NAME is output verbatim. 1758 Otherwise NAME is transformed in an implementation-defined way 1759 (usually by the addition of an underscore). 1760 Many macros in the tm file are defined to call this function. */ 1761 1762void 1763assemble_name (file, name) 1764 FILE *file; 1765 const char *name; 1766{ 1767 const char *real_name; 1768 tree id; 1769 1770 real_name = (* targetm.strip_name_encoding) (name); 1771 1772 id = maybe_get_identifier (real_name); 1773 if (id) 1774 TREE_SYMBOL_REFERENCED (id) = 1; 1775 1776 if (name[0] == '*') 1777 fputs (&name[1], file); 1778 else 1779 ASM_OUTPUT_LABELREF (file, name); 1780} 1781 1782/* Allocate SIZE bytes writable static space with a gensym name 1783 and return an RTX to refer to its address. */ 1784 1785rtx 1786assemble_static_space (size) 1787 int size; 1788{ 1789 char name[12]; 1790 const char *namestring; 1791 rtx x; 1792 1793#if 0 1794 if (flag_shared_data) 1795 data_section (); 1796#endif 1797 1798 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno); 1799 ++const_labelno; 1800 namestring = ggc_strdup (name); 1801 1802 x = gen_rtx_SYMBOL_REF (Pmode, namestring); 1803 1804#ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL 1805 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size, 1806 BIGGEST_ALIGNMENT); 1807#else 1808#ifdef ASM_OUTPUT_ALIGNED_LOCAL 1809 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT); 1810#else 1811 { 1812 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 1813 so that each uninitialized object starts on such a boundary. */ 1814 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */ 1815 int rounded ATTRIBUTE_UNUSED 1816 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1) 1817 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 1818 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 1819 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); 1820 } 1821#endif 1822#endif 1823 return x; 1824} 1825 1826/* Assemble the static constant template for function entry trampolines. 1827 This is done at most once per compilation. 1828 Returns an RTX for the address of the template. */ 1829 1830#ifdef TRAMPOLINE_TEMPLATE 1831rtx 1832assemble_trampoline_template () 1833{ 1834 char label[256]; 1835 const char *name; 1836 int align; 1837 1838 /* By default, put trampoline templates in read-only data section. */ 1839 1840#ifdef TRAMPOLINE_SECTION 1841 TRAMPOLINE_SECTION (); 1842#else 1843 readonly_data_section (); 1844#endif 1845 1846 /* Write the assembler code to define one. */ 1847 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT); 1848 if (align > 0) 1849 { 1850 ASM_OUTPUT_ALIGN (asm_out_file, align); 1851 } 1852 1853 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0); 1854 TRAMPOLINE_TEMPLATE (asm_out_file); 1855 1856 /* Record the rtl to refer to it. */ 1857 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0); 1858 name = ggc_strdup (label); 1859 return gen_rtx_SYMBOL_REF (Pmode, name); 1860} 1861#endif 1862 1863/* A and B are either alignments or offsets. Return the minimum alignment 1864 that may be assumed after adding the two together. */ 1865 1866static inline unsigned 1867min_align (a, b) 1868 unsigned int a, b; 1869{ 1870 return (a | b) & -(a | b); 1871} 1872 1873/* Return the assembler directive for creating a given kind of integer 1874 object. SIZE is the number of bytes in the object and ALIGNED_P 1875 indicates whether it is known to be aligned. Return NULL if the 1876 assembly dialect has no such directive. 1877 1878 The returned string should be printed at the start of a new line and 1879 be followed immediately by the object's initial value. */ 1880 1881const char * 1882integer_asm_op (size, aligned_p) 1883 int size; 1884 int aligned_p; 1885{ 1886 struct asm_int_op *ops; 1887 1888 if (aligned_p) 1889 ops = &targetm.asm_out.aligned_op; 1890 else 1891 ops = &targetm.asm_out.unaligned_op; 1892 1893 switch (size) 1894 { 1895 case 1: 1896 return targetm.asm_out.byte_op; 1897 case 2: 1898 return ops->hi; 1899 case 4: 1900 return ops->si; 1901 case 8: 1902 return ops->di; 1903 case 16: 1904 return ops->ti; 1905 default: 1906 return NULL; 1907 } 1908} 1909 1910/* Use directive OP to assemble an integer object X. Print OP at the 1911 start of the line, followed immediately by the value of X. */ 1912 1913void 1914assemble_integer_with_op (op, x) 1915 const char *op; 1916 rtx x; 1917{ 1918 fputs (op, asm_out_file); 1919 output_addr_const (asm_out_file, x); 1920 fputc ('\n', asm_out_file); 1921} 1922 1923/* The default implementation of the asm_out.integer target hook. */ 1924 1925bool 1926default_assemble_integer (x, size, aligned_p) 1927 rtx x ATTRIBUTE_UNUSED; 1928 unsigned int size ATTRIBUTE_UNUSED; 1929 int aligned_p ATTRIBUTE_UNUSED; 1930{ 1931 const char *op = integer_asm_op (size, aligned_p); 1932 return op && (assemble_integer_with_op (op, x), true); 1933} 1934 1935/* Assemble the integer constant X into an object of SIZE bytes. ALIGN is 1936 the alignment of the integer in bits. Return 1 if we were able to output 1937 the constant, otherwise 0. If FORCE is nonzero, abort if we can't output 1938 the constant. */ 1939 1940bool 1941assemble_integer (x, size, align, force) 1942 rtx x; 1943 unsigned int size; 1944 unsigned int align; 1945 int force; 1946{ 1947 int aligned_p; 1948 1949 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT)); 1950 1951 /* See if the target hook can handle this kind of object. */ 1952 if ((*targetm.asm_out.integer) (x, size, aligned_p)) 1953 return true; 1954 1955 /* If the object is a multi-byte one, try splitting it up. Split 1956 it into words it if is multi-word, otherwise split it into bytes. */ 1957 if (size > 1) 1958 { 1959 enum machine_mode omode, imode; 1960 unsigned int subalign; 1961 unsigned int subsize, i; 1962 1963 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1; 1964 subalign = MIN (align, subsize * BITS_PER_UNIT); 1965 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0); 1966 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0); 1967 1968 for (i = 0; i < size; i += subsize) 1969 { 1970 rtx partial = simplify_subreg (omode, x, imode, i); 1971 if (!partial || !assemble_integer (partial, subsize, subalign, 0)) 1972 break; 1973 } 1974 if (i == size) 1975 return true; 1976 1977 /* If we've printed some of it, but not all of it, there's no going 1978 back now. */ 1979 if (i > 0) 1980 abort (); 1981 } 1982 1983 if (force) 1984 abort (); 1985 1986 return false; 1987} 1988 1989void 1990assemble_real (d, mode, align) 1991 REAL_VALUE_TYPE d; 1992 enum machine_mode mode; 1993 unsigned int align; 1994{ 1995 long data[4]; 1996 long l; 1997 unsigned int nalign = min_align (align, 32); 1998 1999 switch (BITS_PER_UNIT) 2000 { 2001 case 8: 2002 switch (mode) 2003 { 2004 case SFmode: 2005 REAL_VALUE_TO_TARGET_SINGLE (d, l); 2006 assemble_integer (GEN_INT (l), 4, align, 1); 2007 break; 2008 case DFmode: 2009 REAL_VALUE_TO_TARGET_DOUBLE (d, data); 2010 assemble_integer (GEN_INT (data[0]), 4, align, 1); 2011 assemble_integer (GEN_INT (data[1]), 4, nalign, 1); 2012 break; 2013 case XFmode: 2014 REAL_VALUE_TO_TARGET_LONG_DOUBLE (d, data); 2015 assemble_integer (GEN_INT (data[0]), 4, align, 1); 2016 assemble_integer (GEN_INT (data[1]), 4, nalign, 1); 2017 assemble_integer (GEN_INT (data[2]), 4, nalign, 1); 2018 break; 2019 case TFmode: 2020 REAL_VALUE_TO_TARGET_LONG_DOUBLE (d, data); 2021 assemble_integer (GEN_INT (data[0]), 4, align, 1); 2022 assemble_integer (GEN_INT (data[1]), 4, nalign, 1); 2023 assemble_integer (GEN_INT (data[2]), 4, nalign, 1); 2024 assemble_integer (GEN_INT (data[3]), 4, nalign, 1); 2025 break; 2026 default: 2027 abort (); 2028 } 2029 break; 2030 2031 case 16: 2032 switch (mode) 2033 { 2034 case HFmode: 2035 REAL_VALUE_TO_TARGET_SINGLE (d, l); 2036 assemble_integer (GEN_INT (l), 2, align, 1); 2037 break; 2038 case TQFmode: 2039 REAL_VALUE_TO_TARGET_DOUBLE (d, data); 2040 assemble_integer (GEN_INT (data[0]), 2, align, 1); 2041 assemble_integer (GEN_INT (data[1]), 1, nalign, 1); 2042 break; 2043 default: 2044 abort (); 2045 } 2046 break; 2047 2048 case 32: 2049 switch (mode) 2050 { 2051 case QFmode: 2052 REAL_VALUE_TO_TARGET_SINGLE (d, l); 2053 assemble_integer (GEN_INT (l), 1, align, 1); 2054 break; 2055 case HFmode: 2056 REAL_VALUE_TO_TARGET_DOUBLE (d, data); 2057 assemble_integer (GEN_INT (data[0]), 1, align, 1); 2058 assemble_integer (GEN_INT (data[1]), 1, nalign, 1); 2059 break; 2060 default: 2061 abort (); 2062 } 2063 break; 2064 2065 default: 2066 abort (); 2067 } 2068} 2069 2070/* Given an expression EXP with a constant value, 2071 reduce it to the sum of an assembler symbol and an integer. 2072 Store them both in the structure *VALUE. 2073 Abort if EXP does not reduce. */ 2074 2075struct addr_const GTY(()) 2076{ 2077 rtx base; 2078 HOST_WIDE_INT offset; 2079}; 2080 2081static void 2082decode_addr_const (exp, value) 2083 tree exp; 2084 struct addr_const *value; 2085{ 2086 tree target = TREE_OPERAND (exp, 0); 2087 int offset = 0; 2088 rtx x; 2089 2090 while (1) 2091 { 2092 if (TREE_CODE (target) == COMPONENT_REF 2093 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0)) 2094 2095 { 2096 offset += int_byte_position (TREE_OPERAND (target, 1)); 2097 target = TREE_OPERAND (target, 0); 2098 } 2099 else if (TREE_CODE (target) == ARRAY_REF 2100 || TREE_CODE (target) == ARRAY_RANGE_REF) 2101 { 2102 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1) 2103 * tree_low_cst (TREE_OPERAND (target, 1), 0)); 2104 target = TREE_OPERAND (target, 0); 2105 } 2106 else 2107 break; 2108 } 2109 2110 switch (TREE_CODE (target)) 2111 { 2112 case VAR_DECL: 2113 case FUNCTION_DECL: 2114 x = DECL_RTL (target); 2115 break; 2116 2117 case LABEL_DECL: 2118 x = gen_rtx_MEM (FUNCTION_MODE, 2119 gen_rtx_LABEL_REF (VOIDmode, 2120 label_rtx (TREE_OPERAND (exp, 0)))); 2121 break; 2122 2123 case REAL_CST: 2124 case STRING_CST: 2125 case COMPLEX_CST: 2126 case CONSTRUCTOR: 2127 case INTEGER_CST: 2128 /* This constant should have been output already, but we can't simply 2129 use TREE_CST_RTL since INTEGER_CST doesn't have one. */ 2130 x = output_constant_def (target, 1); 2131 break; 2132 2133 default: 2134 abort (); 2135 } 2136 2137 if (GET_CODE (x) != MEM) 2138 abort (); 2139 x = XEXP (x, 0); 2140 2141 value->base = x; 2142 value->offset = offset; 2143} 2144 2145/* We do RTX_UNSPEC + XINT (blah), so nothing can go after RTX_UNSPEC. */ 2146enum kind { RTX_UNKNOWN, RTX_DOUBLE, RTX_VECTOR, RTX_INT, RTX_UNSPEC }; 2147struct rtx_const GTY(()) 2148{ 2149 ENUM_BITFIELD(kind) kind : 16; 2150 ENUM_BITFIELD(machine_mode) mode : 16; 2151 union rtx_const_un { 2152 REAL_VALUE_TYPE du; 2153 struct rtx_const_u_addr { 2154 rtx base; 2155 const char *symbol; 2156 HOST_WIDE_INT offset; 2157 } GTY ((tag ("1"))) addr; 2158 struct rtx_const_u_di { 2159 HOST_WIDE_INT high; 2160 HOST_WIDE_INT low; 2161 } GTY ((tag ("0"))) di; 2162 2163 /* The max vector size we have is 16 wide; two variants for 2164 integral and floating point vectors. */ 2165 struct rtx_const_int_vec { 2166 HOST_WIDE_INT high; 2167 HOST_WIDE_INT low; 2168 } GTY ((tag ("2"))) int_vec[16]; 2169 2170 REAL_VALUE_TYPE GTY ((tag ("3"))) fp_vec[8]; 2171 2172 } GTY ((desc ("%1.kind >= RTX_INT"), descbits ("1"))) un; 2173}; 2174 2175/* Uniquize all constants that appear in memory. 2176 Each constant in memory thus far output is recorded 2177 in `const_hash_table'. */ 2178 2179struct constant_descriptor_tree GTY(()) 2180{ 2181 /* More constant_descriptors with the same hash code. */ 2182 struct constant_descriptor_tree *next; 2183 2184 /* The label of the constant. */ 2185 const char *label; 2186 2187 /* A MEM for the constant. */ 2188 rtx rtl; 2189 2190 /* The value of the constant. */ 2191 tree value; 2192}; 2193 2194#define MAX_HASH_TABLE 1009 2195static GTY(()) struct constant_descriptor_tree * 2196 const_hash_table[MAX_HASH_TABLE]; 2197 2198/* We maintain a hash table of STRING_CST values. Unless we are asked to force 2199 out a string constant, we defer output of the constants until we know 2200 they are actually used. This will be if something takes its address or if 2201 there is a usage of the string in the RTL of a function. */ 2202 2203#define STRHASH(x) htab_hash_pointer (x) 2204 2205struct deferred_string GTY(()) 2206{ 2207 const char *label; 2208 tree exp; 2209 int labelno; 2210}; 2211 2212static GTY ((param_is (struct deferred_string))) htab_t const_str_htab; 2213 2214/* Returns a hash code for X (which is a really a 2215 struct deferred_string *). */ 2216 2217static hashval_t 2218const_str_htab_hash (x) 2219 const void *x; 2220{ 2221 return STRHASH (((const struct deferred_string *) x)->label); 2222} 2223 2224/* Returns nonzero if the value represented by X (which is really a 2225 struct deferred_string *) is the same as that given by Y 2226 (which is really a char *). */ 2227 2228static int 2229const_str_htab_eq (x, y) 2230 const void *x; 2231 const void *y; 2232{ 2233 return (((const struct deferred_string *) x)->label == (const char *) y); 2234} 2235 2236/* Compute a hash code for a constant expression. */ 2237 2238static unsigned int 2239const_hash (exp) 2240 tree exp; 2241{ 2242 return const_hash_1 (exp) % MAX_HASH_TABLE; 2243} 2244 2245static unsigned int 2246const_hash_1 (exp) 2247 tree exp; 2248{ 2249 const char *p; 2250 unsigned int hi; 2251 int len, i; 2252 enum tree_code code = TREE_CODE (exp); 2253 2254 /* Either set P and LEN to the address and len of something to hash and 2255 exit the switch or return a value. */ 2256 2257 switch (code) 2258 { 2259 case INTEGER_CST: 2260 p = (char *) &TREE_INT_CST (exp); 2261 len = sizeof TREE_INT_CST (exp); 2262 break; 2263 2264 case REAL_CST: 2265 return real_hash (TREE_REAL_CST_PTR (exp)); 2266 2267 case STRING_CST: 2268 p = TREE_STRING_POINTER (exp); 2269 len = TREE_STRING_LENGTH (exp); 2270 break; 2271 2272 case COMPLEX_CST: 2273 return (const_hash_1 (TREE_REALPART (exp)) * 5 2274 + const_hash_1 (TREE_IMAGPART (exp))); 2275 2276 case CONSTRUCTOR: 2277 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2278 { 2279 char *tmp; 2280 2281 len = int_size_in_bytes (TREE_TYPE (exp)); 2282 tmp = (char *) alloca (len); 2283 get_set_constructor_bytes (exp, (unsigned char *) tmp, len); 2284 p = tmp; 2285 break; 2286 } 2287 else 2288 { 2289 tree link; 2290 2291 hi = 5 + int_size_in_bytes (TREE_TYPE (exp)); 2292 2293 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2294 if (TREE_VALUE (link)) 2295 hi = hi * 603 + const_hash_1 (TREE_VALUE (link)); 2296 2297 return hi; 2298 } 2299 2300 case ADDR_EXPR: 2301 case FDESC_EXPR: 2302 { 2303 struct addr_const value; 2304 2305 decode_addr_const (exp, &value); 2306 if (GET_CODE (value.base) == SYMBOL_REF) 2307 { 2308 /* Don't hash the address of the SYMBOL_REF; 2309 only use the offset and the symbol name. */ 2310 hi = value.offset; 2311 p = XSTR (value.base, 0); 2312 for (i = 0; p[i] != 0; i++) 2313 hi = ((hi * 613) + (unsigned) (p[i])); 2314 } 2315 else if (GET_CODE (value.base) == LABEL_REF) 2316 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13; 2317 else 2318 abort (); 2319 } 2320 return hi; 2321 2322 case PLUS_EXPR: 2323 case MINUS_EXPR: 2324 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9 2325 + const_hash_1 (TREE_OPERAND (exp, 1))); 2326 2327 case NOP_EXPR: 2328 case CONVERT_EXPR: 2329 case NON_LVALUE_EXPR: 2330 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2; 2331 2332 default: 2333 /* A language specific constant. Just hash the code. */ 2334 return code; 2335 } 2336 2337 /* Compute hashing function */ 2338 hi = len; 2339 for (i = 0; i < len; i++) 2340 hi = ((hi * 613) + (unsigned) (p[i])); 2341 2342 return hi; 2343} 2344 2345/* Compare t1 and t2, and return 1 only if they are known to result in 2346 the same bit pattern on output. */ 2347 2348static int 2349compare_constant (t1, t2) 2350 tree t1; 2351 tree t2; 2352{ 2353 enum tree_code typecode; 2354 2355 if (t1 == NULL_TREE) 2356 return t2 == NULL_TREE; 2357 if (t2 == NULL_TREE) 2358 return 0; 2359 2360 if (TREE_CODE (t1) != TREE_CODE (t2)) 2361 return 0; 2362 2363 switch (TREE_CODE (t1)) 2364 { 2365 case INTEGER_CST: 2366 /* Integer constants are the same only if the same width of type. */ 2367 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2))) 2368 return 0; 2369 return tree_int_cst_equal (t1, t2); 2370 2371 case REAL_CST: 2372 /* Real constants are the same only if the same width of type. */ 2373 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2))) 2374 return 0; 2375 2376 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2)); 2377 2378 case STRING_CST: 2379 if (flag_writable_strings) 2380 return 0; 2381 2382 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))) 2383 return 0; 2384 2385 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2) 2386 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2), 2387 TREE_STRING_LENGTH (t1))); 2388 2389 case COMPLEX_CST: 2390 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2)) 2391 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2))); 2392 2393 case CONSTRUCTOR: 2394 typecode = TREE_CODE (TREE_TYPE (t1)); 2395 if (typecode != TREE_CODE (TREE_TYPE (t2))) 2396 return 0; 2397 2398 if (typecode == SET_TYPE) 2399 { 2400 int len = int_size_in_bytes (TREE_TYPE (t2)); 2401 unsigned char *tmp1, *tmp2; 2402 2403 if (int_size_in_bytes (TREE_TYPE (t1)) != len) 2404 return 0; 2405 2406 tmp1 = (unsigned char *) alloca (len); 2407 tmp2 = (unsigned char *) alloca (len); 2408 2409 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE) 2410 return 0; 2411 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE) 2412 return 0; 2413 2414 return memcmp (tmp1, tmp2, len) != 0; 2415 } 2416 else 2417 { 2418 tree l1, l2; 2419 2420 if (typecode == ARRAY_TYPE) 2421 { 2422 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1)); 2423 /* For arrays, check that the sizes all match. */ 2424 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)) 2425 || size_1 == -1 2426 || size_1 != int_size_in_bytes (TREE_TYPE (t2))) 2427 return 0; 2428 } 2429 else 2430 { 2431 /* For record and union constructors, require exact type 2432 equality. */ 2433 if (TREE_TYPE (t1) != TREE_TYPE (t2)) 2434 return 0; 2435 } 2436 2437 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2); 2438 l1 && l2; 2439 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2)) 2440 { 2441 /* Check that each value is the same... */ 2442 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2))) 2443 return 0; 2444 /* ... and that they apply to the same fields! */ 2445 if (typecode == ARRAY_TYPE) 2446 { 2447 if (! compare_constant (TREE_PURPOSE (l1), 2448 TREE_PURPOSE (l2))) 2449 return 0; 2450 } 2451 else 2452 { 2453 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2)) 2454 return 0; 2455 } 2456 } 2457 2458 return l1 == NULL_TREE && l2 == NULL_TREE; 2459 } 2460 2461 case ADDR_EXPR: 2462 case FDESC_EXPR: 2463 { 2464 struct addr_const value1, value2; 2465 2466 decode_addr_const (t1, &value1); 2467 decode_addr_const (t2, &value2); 2468 return (value1.offset == value2.offset 2469 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0); 2470 } 2471 2472 case PLUS_EXPR: 2473 case MINUS_EXPR: 2474 case RANGE_EXPR: 2475 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0)) 2476 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1))); 2477 2478 case NOP_EXPR: 2479 case CONVERT_EXPR: 2480 case NON_LVALUE_EXPR: 2481 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0)); 2482 2483 default: 2484 { 2485 tree nt1, nt2; 2486 nt1 = (*lang_hooks.expand_constant) (t1); 2487 nt2 = (*lang_hooks.expand_constant) (t2); 2488 if (nt1 != t1 || nt2 != t2) 2489 return compare_constant (nt1, nt2); 2490 else 2491 return 0; 2492 } 2493 } 2494 2495 /* Should not get here. */ 2496 abort (); 2497} 2498 2499/* Record a list of constant expressions that were passed to 2500 output_constant_def but that could not be output right away. */ 2501 2502struct deferred_constant 2503{ 2504 struct deferred_constant *next; 2505 tree exp; 2506 int reloc; 2507 int labelno; 2508}; 2509 2510static struct deferred_constant *deferred_constants; 2511 2512/* Another list of constants which should be output after the 2513 function. */ 2514static struct deferred_constant *after_function_constants; 2515 2516/* Nonzero means defer output of addressed subconstants 2517 (i.e., those for which output_constant_def is called.) */ 2518static int defer_addressed_constants_flag; 2519 2520/* Start deferring output of subconstants. */ 2521 2522void 2523defer_addressed_constants () 2524{ 2525 defer_addressed_constants_flag++; 2526} 2527 2528/* Stop deferring output of subconstants, 2529 and output now all those that have been deferred. */ 2530 2531void 2532output_deferred_addressed_constants () 2533{ 2534 struct deferred_constant *p, *next; 2535 2536 defer_addressed_constants_flag--; 2537 2538 if (defer_addressed_constants_flag > 0) 2539 return; 2540 2541 for (p = deferred_constants; p; p = next) 2542 { 2543 output_constant_def_contents (p->exp, p->reloc, p->labelno); 2544 next = p->next; 2545 free (p); 2546 } 2547 2548 deferred_constants = 0; 2549} 2550 2551/* Output any constants which should appear after a function. */ 2552 2553static void 2554output_after_function_constants () 2555{ 2556 struct deferred_constant *p, *next; 2557 2558 for (p = after_function_constants; p; p = next) 2559 { 2560 output_constant_def_contents (p->exp, p->reloc, p->labelno); 2561 next = p->next; 2562 free (p); 2563 } 2564 2565 after_function_constants = 0; 2566} 2567 2568/* Make a copy of the whole tree structure for a constant. This 2569 handles the same types of nodes that compare_constant handles. */ 2570 2571static tree 2572copy_constant (exp) 2573 tree exp; 2574{ 2575 switch (TREE_CODE (exp)) 2576 { 2577 case ADDR_EXPR: 2578 /* For ADDR_EXPR, we do not want to copy the decl whose address 2579 is requested. We do want to copy constants though. */ 2580 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c') 2581 return build1 (TREE_CODE (exp), TREE_TYPE (exp), 2582 copy_constant (TREE_OPERAND (exp, 0))); 2583 else 2584 return copy_node (exp); 2585 2586 case INTEGER_CST: 2587 case REAL_CST: 2588 case STRING_CST: 2589 return copy_node (exp); 2590 2591 case COMPLEX_CST: 2592 return build_complex (TREE_TYPE (exp), 2593 copy_constant (TREE_REALPART (exp)), 2594 copy_constant (TREE_IMAGPART (exp))); 2595 2596 case PLUS_EXPR: 2597 case MINUS_EXPR: 2598 return build (TREE_CODE (exp), TREE_TYPE (exp), 2599 copy_constant (TREE_OPERAND (exp, 0)), 2600 copy_constant (TREE_OPERAND (exp, 1))); 2601 2602 case NOP_EXPR: 2603 case CONVERT_EXPR: 2604 case NON_LVALUE_EXPR: 2605 return build1 (TREE_CODE (exp), TREE_TYPE (exp), 2606 copy_constant (TREE_OPERAND (exp, 0))); 2607 2608 case CONSTRUCTOR: 2609 { 2610 tree copy = copy_node (exp); 2611 tree list = copy_list (CONSTRUCTOR_ELTS (exp)); 2612 tree tail; 2613 2614 CONSTRUCTOR_ELTS (copy) = list; 2615 for (tail = list; tail; tail = TREE_CHAIN (tail)) 2616 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail)); 2617 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2618 for (tail = list; tail; tail = TREE_CHAIN (tail)) 2619 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail)); 2620 2621 return copy; 2622 } 2623 2624 default: 2625 { 2626 tree t; 2627 t = (*lang_hooks.expand_constant) (exp); 2628 if (t != exp) 2629 return copy_constant (t); 2630 else 2631 abort (); 2632 } 2633 } 2634} 2635 2636/* Return an rtx representing a reference to constant data in memory 2637 for the constant expression EXP. 2638 2639 If assembler code for such a constant has already been output, 2640 return an rtx to refer to it. 2641 Otherwise, output such a constant in memory (or defer it for later) 2642 and generate an rtx for it. 2643 2644 If DEFER is nonzero, the output of string constants can be deferred 2645 and output only if referenced in the function after all optimizations. 2646 2647 The TREE_CST_RTL of EXP is set up to point to that rtx. 2648 The const_hash_table records which constants already have label strings. */ 2649 2650rtx 2651output_constant_def (exp, defer) 2652 tree exp; 2653 int defer; 2654{ 2655 int hash; 2656 struct constant_descriptor_tree *desc; 2657 struct deferred_string **defstr; 2658 char label[256]; 2659 int reloc; 2660 int found = 1; 2661 int after_function = 0; 2662 int labelno = -1; 2663 rtx rtl; 2664 2665 /* We can't just use the saved RTL if this is a deferred string constant 2666 and we are not to defer anymore. */ 2667 if (TREE_CODE (exp) != INTEGER_CST && TREE_CST_RTL (exp) 2668 && (defer || !STRING_POOL_ADDRESS_P (XEXP (TREE_CST_RTL (exp), 0)))) 2669 return TREE_CST_RTL (exp); 2670 2671 /* Make sure any other constants whose addresses appear in EXP 2672 are assigned label numbers. */ 2673 2674 reloc = output_addressed_constants (exp); 2675 2676 /* Compute hash code of EXP. Search the descriptors for that hash code 2677 to see if any of them describes EXP. If yes, the descriptor records 2678 the label number already assigned. */ 2679 2680 hash = const_hash (exp); 2681 2682 for (desc = const_hash_table[hash]; desc; desc = desc->next) 2683 if (compare_constant (exp, desc->value)) 2684 break; 2685 2686 if (desc == 0) 2687 { 2688 /* No constant equal to EXP is known to have been output. 2689 Make a constant descriptor to enter EXP in the hash table. 2690 Assign the label number and record it in the descriptor for 2691 future calls to this function to find. */ 2692 2693 /* Create a string containing the label name, in LABEL. */ 2694 labelno = const_labelno++; 2695 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno); 2696 2697 desc = ggc_alloc (sizeof (*desc)); 2698 desc->next = const_hash_table[hash]; 2699 desc->label = ggc_strdup (label); 2700 desc->value = copy_constant (exp); 2701 const_hash_table[hash] = desc; 2702 2703 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */ 2704 rtl = desc->rtl 2705 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), 2706 gen_rtx_SYMBOL_REF (Pmode, desc->label)); 2707 2708 set_mem_attributes (rtl, exp, 1); 2709 set_mem_alias_set (rtl, 0); 2710 set_mem_alias_set (rtl, const_alias_set); 2711 2712 found = 0; 2713 } 2714 else 2715 rtl = desc->rtl; 2716 2717 if (TREE_CODE (exp) != INTEGER_CST) 2718 TREE_CST_RTL (exp) = rtl; 2719 2720 /* Optionally set flags or add text to the name to record information 2721 such as that it is a function name. If the name is changed, the macro 2722 ASM_OUTPUT_LABELREF will have to know how to strip this information. */ 2723 /* A previously-processed constant would already have section info 2724 encoded in it. */ 2725 if (! found) 2726 { 2727 /* Take care not to invoke targetm.encode_section_info for 2728 constants which don't have a TREE_CST_RTL. */ 2729 if (TREE_CODE (exp) != INTEGER_CST) 2730 (*targetm.encode_section_info) (exp, true); 2731 2732 desc->rtl = rtl; 2733 desc->label = XSTR (XEXP (desc->rtl, 0), 0); 2734 } 2735 2736#ifdef CONSTANT_AFTER_FUNCTION_P 2737 if (current_function_decl != 0 2738 && CONSTANT_AFTER_FUNCTION_P (exp)) 2739 after_function = 1; 2740#endif 2741 2742 if (found 2743 && STRING_POOL_ADDRESS_P (XEXP (rtl, 0)) 2744 && (!defer || defer_addressed_constants_flag || after_function)) 2745 { 2746 defstr = (struct deferred_string **) 2747 htab_find_slot_with_hash (const_str_htab, desc->label, 2748 STRHASH (desc->label), NO_INSERT); 2749 if (defstr) 2750 { 2751 /* If the string is currently deferred but we need to output it now, 2752 remove it from deferred string hash table. */ 2753 found = 0; 2754 labelno = (*defstr)->labelno; 2755 STRING_POOL_ADDRESS_P (XEXP (rtl, 0)) = 0; 2756 htab_clear_slot (const_str_htab, (void **) defstr); 2757 } 2758 } 2759 2760 /* If this is the first time we've seen this particular constant, 2761 output it (or defer its output for later). */ 2762 if (! found) 2763 { 2764 if (defer_addressed_constants_flag || after_function) 2765 { 2766 struct deferred_constant *p 2767 = (struct deferred_constant *) 2768 xmalloc (sizeof (struct deferred_constant)); 2769 2770 p->exp = desc->value; 2771 p->reloc = reloc; 2772 p->labelno = labelno; 2773 if (after_function) 2774 { 2775 p->next = after_function_constants; 2776 after_function_constants = p; 2777 } 2778 else 2779 { 2780 p->next = deferred_constants; 2781 deferred_constants = p; 2782 } 2783 } 2784 else 2785 { 2786 /* Do no output if -fsyntax-only. */ 2787 if (! flag_syntax_only) 2788 { 2789 if (TREE_CODE (exp) != STRING_CST 2790 || !defer 2791 || flag_writable_strings 2792 || (defstr = (struct deferred_string **) 2793 htab_find_slot_with_hash (const_str_htab, 2794 desc->label, 2795 STRHASH (desc->label), 2796 INSERT)) == NULL) 2797 output_constant_def_contents (exp, reloc, labelno); 2798 else 2799 { 2800 struct deferred_string *p; 2801 2802 p = (struct deferred_string *) 2803 ggc_alloc (sizeof (struct deferred_string)); 2804 2805 p->exp = desc->value; 2806 p->label = desc->label; 2807 p->labelno = labelno; 2808 *defstr = p; 2809 STRING_POOL_ADDRESS_P (XEXP (rtl, 0)) = 1; 2810 } 2811 } 2812 } 2813 } 2814 2815 return rtl; 2816} 2817 2818/* Now output assembler code to define the label for EXP, 2819 and follow it with the data of EXP. */ 2820 2821static void 2822output_constant_def_contents (exp, reloc, labelno) 2823 tree exp; 2824 int reloc; 2825 int labelno; 2826{ 2827 int align; 2828 2829 /* Align the location counter as required by EXP's data type. */ 2830 align = TYPE_ALIGN (TREE_TYPE (exp)); 2831#ifdef CONSTANT_ALIGNMENT 2832 align = CONSTANT_ALIGNMENT (exp, align); 2833#endif 2834 2835 if (IN_NAMED_SECTION (exp)) 2836 named_section (exp, NULL, reloc); 2837 else 2838 (*targetm.asm_out.select_section) (exp, reloc, align); 2839 2840 if (align > BITS_PER_UNIT) 2841 { 2842 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 2843 } 2844 2845 /* Output the label itself. */ 2846 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", labelno); 2847 2848 /* Output the value of EXP. */ 2849 output_constant (exp, 2850 (TREE_CODE (exp) == STRING_CST 2851 ? MAX (TREE_STRING_LENGTH (exp), 2852 int_size_in_bytes (TREE_TYPE (exp))) 2853 : int_size_in_bytes (TREE_TYPE (exp))), 2854 align); 2855 2856} 2857 2858/* Used in the hash tables to avoid outputting the same constant 2859 twice. Unlike 'struct constant_descriptor_tree', RTX constants 2860 are output once per function, not once per file; there seems 2861 to be no reason for the difference. */ 2862 2863struct constant_descriptor_rtx GTY(()) 2864{ 2865 /* More constant_descriptors with the same hash code. */ 2866 struct constant_descriptor_rtx *next; 2867 2868 /* A MEM for the constant. */ 2869 rtx rtl; 2870 2871 /* The value of the constant. */ 2872 struct rtx_const value; 2873}; 2874 2875/* Structure to represent sufficient information about a constant so that 2876 it can be output when the constant pool is output, so that function 2877 integration can be done, and to simplify handling on machines that reference 2878 constant pool as base+displacement. */ 2879 2880struct pool_constant GTY(()) 2881{ 2882 struct constant_descriptor_rtx *desc; 2883 struct pool_constant *next; 2884 struct pool_constant *next_sym; 2885 rtx constant; 2886 enum machine_mode mode; 2887 int labelno; 2888 unsigned int align; 2889 HOST_WIDE_INT offset; 2890 int mark; 2891}; 2892 2893/* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true. 2894 The argument is XSTR (... , 0) */ 2895 2896#define SYMHASH(LABEL) (((unsigned long) (LABEL)) % MAX_RTX_HASH_TABLE) 2897 2898/* Initialize constant pool hashing for a new function. */ 2899 2900void 2901init_varasm_status (f) 2902 struct function *f; 2903{ 2904 struct varasm_status *p; 2905 p = (struct varasm_status *) ggc_alloc (sizeof (struct varasm_status)); 2906 f->varasm = p; 2907 p->x_const_rtx_hash_table 2908 = ((struct constant_descriptor_rtx **) 2909 ggc_alloc_cleared (MAX_RTX_HASH_TABLE 2910 * sizeof (struct constant_descriptor_rtx *))); 2911 p->x_const_rtx_sym_hash_table 2912 = ((struct pool_constant **) 2913 ggc_alloc_cleared (MAX_RTX_HASH_TABLE 2914 * sizeof (struct pool_constant *))); 2915 2916 p->x_first_pool = p->x_last_pool = 0; 2917 p->x_pool_offset = 0; 2918} 2919 2920 2921/* Express an rtx for a constant integer (perhaps symbolic) 2922 as the sum of a symbol or label plus an explicit integer. 2923 They are stored into VALUE. */ 2924 2925static void 2926decode_rtx_const (mode, x, value) 2927 enum machine_mode mode; 2928 rtx x; 2929 struct rtx_const *value; 2930{ 2931 /* Clear the whole structure, including any gaps. */ 2932 memset (value, 0, sizeof (struct rtx_const)); 2933 2934 value->kind = RTX_INT; /* Most usual kind. */ 2935 value->mode = mode; 2936 2937 switch (GET_CODE (x)) 2938 { 2939 case CONST_DOUBLE: 2940 value->kind = RTX_DOUBLE; 2941 if (GET_MODE (x) != VOIDmode) 2942 { 2943 const REAL_VALUE_TYPE *r = CONST_DOUBLE_REAL_VALUE (x); 2944 2945 value->mode = GET_MODE (x); 2946 2947 /* Copy the REAL_VALUE_TYPE by members so that we don't 2948 copy garbage from the original structure into our 2949 carefully cleaned hashing structure. */ 2950 value->un.du.class = r->class; 2951 value->un.du.sign = r->sign; 2952 switch (r->class) 2953 { 2954 case rvc_zero: 2955 case rvc_inf: 2956 break; 2957 case rvc_normal: 2958 value->un.du.exp = r->exp; 2959 /* FALLTHRU */ 2960 case rvc_nan: 2961 memcpy (value->un.du.sig, r->sig, sizeof (r->sig)); 2962 break; 2963 default: 2964 abort (); 2965 } 2966 } 2967 else 2968 { 2969 value->un.di.low = CONST_DOUBLE_LOW (x); 2970 value->un.di.high = CONST_DOUBLE_HIGH (x); 2971 } 2972 break; 2973 2974 case CONST_VECTOR: 2975 { 2976 int units, i; 2977 2978 units = CONST_VECTOR_NUNITS (x); 2979 value->kind = RTX_VECTOR; 2980 value->mode = mode; 2981 2982 if (GET_MODE_CLASS (mode) == MODE_VECTOR_INT) 2983 { 2984 for (i = 0; i < units; ++i) 2985 { 2986 rtx elt = CONST_VECTOR_ELT (x, i); 2987 if (GET_CODE (elt) == CONST_INT) 2988 { 2989 value->un.int_vec[i].low = INTVAL (elt); 2990 value->un.int_vec[i].high = 0; 2991 } 2992 else 2993 { 2994 value->un.int_vec[i].low = CONST_DOUBLE_LOW (elt); 2995 value->un.int_vec[i].high = CONST_DOUBLE_HIGH (elt); 2996 } 2997 } 2998 } 2999 else if (GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT) 3000 { 3001 for (i = 0; i < units; ++i) 3002 { 3003 const REAL_VALUE_TYPE *r 3004 = CONST_DOUBLE_REAL_VALUE (CONST_VECTOR_ELT (x, i)); 3005 REAL_VALUE_TYPE *d = &value->un.fp_vec[i]; 3006 3007 /* Copy the REAL_VALUE_TYPE by members so that we don't 3008 copy garbage from the original structure into our 3009 carefully cleaned hashing structure. */ 3010 d->class = r->class; 3011 d->sign = r->sign; 3012 switch (r->class) 3013 { 3014 case rvc_zero: 3015 case rvc_inf: 3016 break; 3017 case rvc_normal: 3018 d->exp = r->exp; 3019 /* FALLTHRU */ 3020 case rvc_nan: 3021 memcpy (d->sig, r->sig, sizeof (r->sig)); 3022 break; 3023 default: 3024 abort (); 3025 } 3026 } 3027 } 3028 else 3029 abort (); 3030 } 3031 break; 3032 3033 case CONST_INT: 3034 value->un.addr.offset = INTVAL (x); 3035 break; 3036 3037 case SYMBOL_REF: 3038 case LABEL_REF: 3039 case PC: 3040 value->un.addr.base = x; 3041 break; 3042 3043 case CONST: 3044 x = XEXP (x, 0); 3045 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT) 3046 { 3047 value->un.addr.base = XEXP (x, 0); 3048 value->un.addr.offset = INTVAL (XEXP (x, 1)); 3049 } 3050 else if (GET_CODE (x) == MINUS && GET_CODE (XEXP (x, 1)) == CONST_INT) 3051 { 3052 value->un.addr.base = XEXP (x, 0); 3053 value->un.addr.offset = - INTVAL (XEXP (x, 1)); 3054 } 3055 else 3056 { 3057 value->un.addr.base = x; 3058 value->un.addr.offset = 0; 3059 } 3060 break; 3061 3062 default: 3063 value->kind = RTX_UNKNOWN; 3064 break; 3065 } 3066 3067 if (value->kind == RTX_INT && value->un.addr.base != 0 3068 && GET_CODE (value->un.addr.base) == UNSPEC) 3069 { 3070 /* For a simple UNSPEC, the base is set to the 3071 operand, the kind field is set to the index of 3072 the unspec expression. 3073 Together with the code below, in case that 3074 the operand is a SYMBOL_REF or LABEL_REF, 3075 the address of the string or the code_label 3076 is taken as base. */ 3077 if (XVECLEN (value->un.addr.base, 0) == 1) 3078 { 3079 value->kind = RTX_UNSPEC + XINT (value->un.addr.base, 1); 3080 value->un.addr.base = XVECEXP (value->un.addr.base, 0, 0); 3081 } 3082 } 3083 3084 if (value->kind >= RTX_INT && value->un.addr.base != 0) 3085 switch (GET_CODE (value->un.addr.base)) 3086 { 3087 case SYMBOL_REF: 3088 /* Use the string's address, not the SYMBOL_REF's address, 3089 for the sake of addresses of library routines. */ 3090 value->un.addr.symbol = XSTR (value->un.addr.base, 0); 3091 value->un.addr.base = NULL_RTX; 3092 break; 3093 3094 case LABEL_REF: 3095 /* For a LABEL_REF, compare labels. */ 3096 value->un.addr.base = XEXP (value->un.addr.base, 0); 3097 3098 default: 3099 break; 3100 } 3101} 3102 3103/* Given a MINUS expression, simplify it if both sides 3104 include the same symbol. */ 3105 3106rtx 3107simplify_subtraction (x) 3108 rtx x; 3109{ 3110 struct rtx_const val0, val1; 3111 3112 decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0); 3113 decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1); 3114 3115 if (val0.kind >= RTX_INT 3116 && val0.kind == val1.kind 3117 && val0.un.addr.base == val1.un.addr.base 3118 && val0.un.addr.symbol == val1.un.addr.symbol) 3119 return GEN_INT (val0.un.addr.offset - val1.un.addr.offset); 3120 3121 return x; 3122} 3123 3124/* Compute a hash code for a constant RTL expression. */ 3125 3126static unsigned int 3127const_hash_rtx (mode, x) 3128 enum machine_mode mode; 3129 rtx x; 3130{ 3131 union { 3132 struct rtx_const value; 3133 unsigned int data[sizeof(struct rtx_const) / sizeof (unsigned int)]; 3134 } u; 3135 3136 unsigned int hi; 3137 size_t i; 3138 3139 decode_rtx_const (mode, x, &u.value); 3140 3141 /* Compute hashing function */ 3142 hi = 0; 3143 for (i = 0; i < ARRAY_SIZE (u.data); i++) 3144 hi = hi * 613 + u.data[i]; 3145 3146 return hi % MAX_RTX_HASH_TABLE; 3147} 3148 3149/* Compare a constant rtl object X with a constant-descriptor DESC. 3150 Return 1 if DESC describes a constant with the same value as X. */ 3151 3152static int 3153compare_constant_rtx (mode, x, desc) 3154 enum machine_mode mode; 3155 rtx x; 3156 struct constant_descriptor_rtx *desc; 3157{ 3158 struct rtx_const value; 3159 3160 decode_rtx_const (mode, x, &value); 3161 3162 /* Compare constant contents. */ 3163 return memcmp (&value, &desc->value, sizeof (struct rtx_const)) == 0; 3164} 3165 3166/* Construct a constant descriptor for the rtl-expression X. 3167 It is up to the caller to enter the descriptor in the hash table. */ 3168 3169static struct constant_descriptor_rtx * 3170record_constant_rtx (mode, x) 3171 enum machine_mode mode; 3172 rtx x; 3173{ 3174 struct constant_descriptor_rtx *ptr; 3175 3176 ptr = (struct constant_descriptor_rtx *) ggc_alloc (sizeof (*ptr)); 3177 decode_rtx_const (mode, x, &ptr->value); 3178 3179 return ptr; 3180} 3181 3182/* Given a constant rtx X, return a MEM for the location in memory at which 3183 this constant has been placed. Return 0 if it not has been placed yet. */ 3184 3185rtx 3186mem_for_const_double (x) 3187 rtx x; 3188{ 3189 enum machine_mode mode = GET_MODE (x); 3190 struct constant_descriptor_rtx *desc; 3191 3192 for (desc = const_rtx_hash_table[const_hash_rtx (mode, x)]; desc; 3193 desc = desc->next) 3194 if (compare_constant_rtx (mode, x, desc)) 3195 return desc->rtl; 3196 3197 return 0; 3198} 3199 3200/* Given a constant rtx X, make (or find) a memory constant for its value 3201 and return a MEM rtx to refer to it in memory. */ 3202 3203rtx 3204force_const_mem (mode, x) 3205 enum machine_mode mode; 3206 rtx x; 3207{ 3208 int hash; 3209 struct constant_descriptor_rtx *desc; 3210 char label[256]; 3211 rtx def; 3212 struct pool_constant *pool; 3213 unsigned int align; 3214 3215 /* If we're not allowed to drop X into the constant pool, don't. */ 3216 if ((*targetm.cannot_force_const_mem) (x)) 3217 return NULL_RTX; 3218 3219 /* Compute hash code of X. Search the descriptors for that hash code 3220 to see if any of them describes X. If yes, we have an rtx to use. */ 3221 hash = const_hash_rtx (mode, x); 3222 for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next) 3223 if (compare_constant_rtx (mode, x, desc)) 3224 return desc->rtl; 3225 3226 /* No constant equal to X is known to have been output. 3227 Make a constant descriptor to enter X in the hash table 3228 and make a MEM for it. */ 3229 desc = record_constant_rtx (mode, x); 3230 desc->next = const_rtx_hash_table[hash]; 3231 const_rtx_hash_table[hash] = desc; 3232 3233 /* Align the location counter as required by EXP's data type. */ 3234 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode); 3235#ifdef CONSTANT_ALIGNMENT 3236 align = CONSTANT_ALIGNMENT (make_tree ((*lang_hooks.types.type_for_mode) 3237 (mode, 0), x), align); 3238#endif 3239 3240 pool_offset += (align / BITS_PER_UNIT) - 1; 3241 pool_offset &= ~ ((align / BITS_PER_UNIT) - 1); 3242 3243 if (GET_CODE (x) == LABEL_REF) 3244 LABEL_PRESERVE_P (XEXP (x, 0)) = 1; 3245 3246 /* Allocate a pool constant descriptor, fill it in, and chain it in. */ 3247 pool = (struct pool_constant *) ggc_alloc (sizeof (struct pool_constant)); 3248 pool->desc = desc; 3249 pool->constant = x; 3250 pool->mode = mode; 3251 pool->labelno = const_labelno; 3252 pool->align = align; 3253 pool->offset = pool_offset; 3254 pool->mark = 1; 3255 pool->next = 0; 3256 3257 if (last_pool == 0) 3258 first_pool = pool; 3259 else 3260 last_pool->next = pool; 3261 3262 last_pool = pool; 3263 pool_offset += GET_MODE_SIZE (mode); 3264 3265 /* Create a string containing the label name, in LABEL. */ 3266 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 3267 3268 ++const_labelno; 3269 3270 /* Construct the SYMBOL_REF and the MEM. */ 3271 3272 pool->desc->rtl = def 3273 = gen_rtx_MEM (mode, gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label))); 3274 set_mem_alias_set (def, const_alias_set); 3275 set_mem_attributes (def, (*lang_hooks.types.type_for_mode) (mode, 0), 1); 3276 RTX_UNCHANGING_P (def) = 1; 3277 3278 /* Add label to symbol hash table. */ 3279 hash = SYMHASH (XSTR (XEXP (def, 0), 0)); 3280 pool->next_sym = const_rtx_sym_hash_table[hash]; 3281 const_rtx_sym_hash_table[hash] = pool; 3282 3283 /* Mark the symbol_ref as belonging to this constants pool. */ 3284 CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1; 3285 current_function_uses_const_pool = 1; 3286 3287 return def; 3288} 3289 3290/* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to 3291 the corresponding pool_constant structure. */ 3292 3293static struct pool_constant * 3294find_pool_constant (f, addr) 3295 struct function *f; 3296 rtx addr; 3297{ 3298 struct pool_constant *pool; 3299 const char *label = XSTR (addr, 0); 3300 3301 for (pool = f->varasm->x_const_rtx_sym_hash_table[SYMHASH (label)]; pool; 3302 pool = pool->next_sym) 3303 if (XSTR (XEXP (pool->desc->rtl, 0), 0) == label) 3304 return pool; 3305 3306 abort (); 3307} 3308 3309/* Given a constant pool SYMBOL_REF, return the corresponding constant. */ 3310 3311rtx 3312get_pool_constant (addr) 3313 rtx addr; 3314{ 3315 return (find_pool_constant (cfun, addr))->constant; 3316} 3317 3318/* Given a constant pool SYMBOL_REF, return the corresponding constant 3319 and whether it has been output or not. */ 3320 3321rtx 3322get_pool_constant_mark (addr, pmarked) 3323 rtx addr; 3324 bool *pmarked; 3325{ 3326 struct pool_constant *pool = find_pool_constant (cfun, addr); 3327 *pmarked = (pool->mark != 0); 3328 return pool->constant; 3329} 3330 3331/* Likewise, but for the constant pool of a specific function. */ 3332 3333rtx 3334get_pool_constant_for_function (f, addr) 3335 struct function *f; 3336 rtx addr; 3337{ 3338 return (find_pool_constant (f, addr))->constant; 3339} 3340 3341/* Similar, return the mode. */ 3342 3343enum machine_mode 3344get_pool_mode (addr) 3345 rtx addr; 3346{ 3347 return (find_pool_constant (cfun, addr))->mode; 3348} 3349 3350enum machine_mode 3351get_pool_mode_for_function (f, addr) 3352 struct function *f; 3353 rtx addr; 3354{ 3355 return (find_pool_constant (f, addr))->mode; 3356} 3357 3358/* Similar, return the offset in the constant pool. */ 3359 3360int 3361get_pool_offset (addr) 3362 rtx addr; 3363{ 3364 return (find_pool_constant (cfun, addr))->offset; 3365} 3366 3367/* Return the size of the constant pool. */ 3368 3369int 3370get_pool_size () 3371{ 3372 return pool_offset; 3373} 3374 3375/* Write all the constants in the constant pool. */ 3376 3377void 3378output_constant_pool (fnname, fndecl) 3379 const char *fnname ATTRIBUTE_UNUSED; 3380 tree fndecl ATTRIBUTE_UNUSED; 3381{ 3382 struct pool_constant *pool; 3383 rtx x; 3384 REAL_VALUE_TYPE r; 3385 3386 /* It is possible for gcc to call force_const_mem and then to later 3387 discard the instructions which refer to the constant. In such a 3388 case we do not need to output the constant. */ 3389 mark_constant_pool (); 3390 3391#ifdef ASM_OUTPUT_POOL_PROLOGUE 3392 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset); 3393#endif 3394 3395 for (pool = first_pool; pool; pool = pool->next) 3396 { 3397 rtx tmp; 3398 3399 x = pool->constant; 3400 3401 if (! pool->mark) 3402 continue; 3403 3404 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF) 3405 whose CODE_LABEL has been deleted. This can occur if a jump table 3406 is eliminated by optimization. If so, write a constant of zero 3407 instead. Note that this can also happen by turning the 3408 CODE_LABEL into a NOTE. */ 3409 /* ??? This seems completely and utterly wrong. Certainly it's 3410 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper 3411 functioning even with INSN_DELETED_P and friends. */ 3412 3413 tmp = x; 3414 switch (GET_CODE (x)) 3415 { 3416 case CONST: 3417 if (GET_CODE (XEXP (x, 0)) != PLUS 3418 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF) 3419 break; 3420 tmp = XEXP (XEXP (x, 0), 0); 3421 /* FALLTHRU */ 3422 3423 case LABEL_REF: 3424 tmp = XEXP (x, 0); 3425 if (INSN_DELETED_P (tmp) 3426 || (GET_CODE (tmp) == NOTE 3427 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED)) 3428 { 3429 abort (); 3430 x = const0_rtx; 3431 } 3432 break; 3433 3434 default: 3435 break; 3436 } 3437 3438 /* First switch to correct section. */ 3439 (*targetm.asm_out.select_rtx_section) (pool->mode, x, pool->align); 3440 3441#ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 3442 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode, 3443 pool->align, pool->labelno, done); 3444#endif 3445 3446 assemble_align (pool->align); 3447 3448 /* Output the label. */ 3449 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno); 3450 3451 /* Output the value of the constant itself. */ 3452 switch (GET_MODE_CLASS (pool->mode)) 3453 { 3454 case MODE_FLOAT: 3455 if (GET_CODE (x) != CONST_DOUBLE) 3456 abort (); 3457 3458 REAL_VALUE_FROM_CONST_DOUBLE (r, x); 3459 assemble_real (r, pool->mode, pool->align); 3460 break; 3461 3462 case MODE_INT: 3463 case MODE_PARTIAL_INT: 3464 assemble_integer (x, GET_MODE_SIZE (pool->mode), pool->align, 1); 3465 break; 3466 3467 case MODE_VECTOR_FLOAT: 3468 { 3469 int i, units; 3470 rtx elt; 3471 3472 if (GET_CODE (x) != CONST_VECTOR) 3473 abort (); 3474 3475 units = CONST_VECTOR_NUNITS (x); 3476 3477 for (i = 0; i < units; i++) 3478 { 3479 elt = CONST_VECTOR_ELT (x, i); 3480 REAL_VALUE_FROM_CONST_DOUBLE (r, elt); 3481 assemble_real (r, GET_MODE_INNER (pool->mode), pool->align); 3482 } 3483 } 3484 break; 3485 3486 case MODE_VECTOR_INT: 3487 { 3488 int i, units; 3489 rtx elt; 3490 3491 if (GET_CODE (x) != CONST_VECTOR) 3492 abort (); 3493 3494 units = CONST_VECTOR_NUNITS (x); 3495 3496 for (i = 0; i < units; i++) 3497 { 3498 elt = CONST_VECTOR_ELT (x, i); 3499 assemble_integer (elt, GET_MODE_UNIT_SIZE (pool->mode), 3500 pool->align, 1); 3501 } 3502 } 3503 break; 3504 3505 default: 3506 abort (); 3507 } 3508 3509 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS 3510 sections have proper size. */ 3511 if (pool->align > GET_MODE_BITSIZE (pool->mode) 3512 && in_section == in_named 3513 && get_named_section_flags (in_named_name) & SECTION_MERGE) 3514 assemble_align (pool->align); 3515 3516#ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 3517 done: ; 3518#endif 3519 } 3520 3521#ifdef ASM_OUTPUT_POOL_EPILOGUE 3522 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool_offset); 3523#endif 3524 3525 /* Done with this pool. */ 3526 first_pool = last_pool = 0; 3527} 3528 3529/* Look through the instructions for this function, and mark all the 3530 entries in the constant pool which are actually being used. 3531 Emit used deferred strings. */ 3532 3533static void 3534mark_constant_pool () 3535{ 3536 rtx insn; 3537 rtx link; 3538 struct pool_constant *pool; 3539 3540 if (first_pool == 0 && htab_elements (const_str_htab) == 0) 3541 return; 3542 3543 for (pool = first_pool; pool; pool = pool->next) 3544 pool->mark = 0; 3545 3546 for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) 3547 if (INSN_P (insn)) 3548 mark_constants (PATTERN (insn)); 3549 3550 for (link = current_function_epilogue_delay_list; 3551 link; 3552 link = XEXP (link, 1)) 3553 { 3554 insn = XEXP (link, 0); 3555 3556 if (INSN_P (insn)) 3557 mark_constants (PATTERN (insn)); 3558 } 3559} 3560 3561/* Look through appropriate parts of X, marking all entries in the 3562 constant pool which are actually being used. Entries that are only 3563 referenced by other constants are also marked as used. Emit 3564 deferred strings that are used. */ 3565 3566static void 3567mark_constants (x) 3568 rtx x; 3569{ 3570 int i; 3571 const char *format_ptr; 3572 3573 if (x == 0) 3574 return; 3575 3576 if (GET_CODE (x) == SYMBOL_REF) 3577 { 3578 mark_constant (&x, NULL); 3579 return; 3580 } 3581 3582 /* Insns may appear inside a SEQUENCE. Only check the patterns of 3583 insns, not any notes that may be attached. We don't want to mark 3584 a constant just because it happens to appear in a REG_EQUIV note. */ 3585 if (INSN_P (x)) 3586 { 3587 mark_constants (PATTERN (x)); 3588 return; 3589 } 3590 3591 format_ptr = GET_RTX_FORMAT (GET_CODE (x)); 3592 3593 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (x)); i++) 3594 { 3595 switch (*format_ptr++) 3596 { 3597 case 'e': 3598 mark_constants (XEXP (x, i)); 3599 break; 3600 3601 case 'E': 3602 if (XVEC (x, i) != 0) 3603 { 3604 int j; 3605 3606 for (j = 0; j < XVECLEN (x, i); j++) 3607 mark_constants (XVECEXP (x, i, j)); 3608 } 3609 break; 3610 3611 case 'S': 3612 case 's': 3613 case '0': 3614 case 'i': 3615 case 'w': 3616 case 'n': 3617 case 'u': 3618 case 'B': 3619 break; 3620 3621 default: 3622 abort (); 3623 } 3624 } 3625} 3626 3627/* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers 3628 to as used. Emit referenced deferred strings. This function can 3629 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */ 3630 3631static int 3632mark_constant (current_rtx, data) 3633 rtx *current_rtx; 3634 void *data ATTRIBUTE_UNUSED; 3635{ 3636 rtx x = *current_rtx; 3637 3638 if (x == NULL_RTX) 3639 return 0; 3640 3641 else if (GET_CODE (x) == SYMBOL_REF) 3642 { 3643 if (CONSTANT_POOL_ADDRESS_P (x)) 3644 { 3645 struct pool_constant *pool = find_pool_constant (cfun, x); 3646 if (pool->mark == 0) 3647 { 3648 pool->mark = 1; 3649 for_each_rtx (&(pool->constant), &mark_constant, NULL); 3650 } 3651 else 3652 return -1; 3653 } 3654 else if (STRING_POOL_ADDRESS_P (x)) 3655 { 3656 struct deferred_string **defstr; 3657 3658 defstr = (struct deferred_string **) 3659 htab_find_slot_with_hash (const_str_htab, XSTR (x, 0), 3660 STRHASH (XSTR (x, 0)), NO_INSERT); 3661 if (defstr) 3662 { 3663 struct deferred_string *p = *defstr; 3664 3665 STRING_POOL_ADDRESS_P (x) = 0; 3666 output_constant_def_contents (p->exp, 0, p->labelno); 3667 htab_clear_slot (const_str_htab, (void **) defstr); 3668 } 3669 } 3670 } 3671 return 0; 3672} 3673 3674/* Find all the constants whose addresses are referenced inside of EXP, 3675 and make sure assembler code with a label has been output for each one. 3676 Indicate whether an ADDR_EXPR has been encountered. */ 3677 3678static int 3679output_addressed_constants (exp) 3680 tree exp; 3681{ 3682 int reloc = 0, reloc2; 3683 tree tem; 3684 3685 /* Give the front-end a chance to convert VALUE to something that 3686 looks more like a constant to the back-end. */ 3687 exp = (*lang_hooks.expand_constant) (exp); 3688 3689 switch (TREE_CODE (exp)) 3690 { 3691 case ADDR_EXPR: 3692 case FDESC_EXPR: 3693 /* Go inside any operations that get_inner_reference can handle and see 3694 if what's inside is a constant: no need to do anything here for 3695 addresses of variables or functions. */ 3696 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem); 3697 tem = TREE_OPERAND (tem, 0)) 3698 ; 3699 3700 if (TREE_CODE_CLASS (TREE_CODE (tem)) == 'c' 3701 || TREE_CODE (tem) == CONSTRUCTOR) 3702 output_constant_def (tem, 0); 3703 3704 if (TREE_PUBLIC (tem)) 3705 reloc |= 2; 3706 else 3707 reloc |= 1; 3708 break; 3709 3710 case PLUS_EXPR: 3711 reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); 3712 reloc |= output_addressed_constants (TREE_OPERAND (exp, 1)); 3713 break; 3714 3715 case MINUS_EXPR: 3716 reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); 3717 reloc2 = output_addressed_constants (TREE_OPERAND (exp, 1)); 3718 /* The difference of two local labels is computable at link time. */ 3719 if (reloc == 1 && reloc2 == 1) 3720 reloc = 0; 3721 else 3722 reloc |= reloc2; 3723 break; 3724 3725 case NOP_EXPR: 3726 case CONVERT_EXPR: 3727 case NON_LVALUE_EXPR: 3728 reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); 3729 break; 3730 3731 case CONSTRUCTOR: 3732 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem)) 3733 if (TREE_VALUE (tem) != 0) 3734 reloc |= output_addressed_constants (TREE_VALUE (tem)); 3735 3736 break; 3737 3738 default: 3739 break; 3740 } 3741 return reloc; 3742} 3743 3744/* Return nonzero if VALUE is a valid constant-valued expression 3745 for use in initializing a static variable; one that can be an 3746 element of a "constant" initializer. 3747 3748 Return null_pointer_node if the value is absolute; 3749 if it is relocatable, return the variable that determines the relocation. 3750 We assume that VALUE has been folded as much as possible; 3751 therefore, we do not need to check for such things as 3752 arithmetic-combinations of integers. */ 3753 3754tree 3755initializer_constant_valid_p (value, endtype) 3756 tree value; 3757 tree endtype; 3758{ 3759 /* Give the front-end a chance to convert VALUE to something that 3760 looks more like a constant to the back-end. */ 3761 value = (*lang_hooks.expand_constant) (value); 3762 3763 switch (TREE_CODE (value)) 3764 { 3765 case CONSTRUCTOR: 3766 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE 3767 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE) 3768 && TREE_CONSTANT (value) 3769 && CONSTRUCTOR_ELTS (value)) 3770 return 3771 initializer_constant_valid_p (TREE_VALUE (CONSTRUCTOR_ELTS (value)), 3772 endtype); 3773 3774 return TREE_STATIC (value) ? null_pointer_node : 0; 3775 3776 case INTEGER_CST: 3777 case VECTOR_CST: 3778 case REAL_CST: 3779 case STRING_CST: 3780 case COMPLEX_CST: 3781 return null_pointer_node; 3782 3783 case ADDR_EXPR: 3784 case FDESC_EXPR: 3785 return staticp (TREE_OPERAND (value, 0)) ? TREE_OPERAND (value, 0) : 0; 3786 3787 case VIEW_CONVERT_EXPR: 3788 case NON_LVALUE_EXPR: 3789 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); 3790 3791 case CONVERT_EXPR: 3792 case NOP_EXPR: 3793 /* Allow conversions between pointer types. */ 3794 if (POINTER_TYPE_P (TREE_TYPE (value)) 3795 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))) 3796 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); 3797 3798 /* Allow conversions between real types. */ 3799 if (FLOAT_TYPE_P (TREE_TYPE (value)) 3800 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))) 3801 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); 3802 3803 /* Allow length-preserving conversions between integer types. */ 3804 if (INTEGRAL_TYPE_P (TREE_TYPE (value)) 3805 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))) 3806 && (TYPE_PRECISION (TREE_TYPE (value)) 3807 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))) 3808 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); 3809 3810 /* Allow conversions between other integer types only if 3811 explicit value. */ 3812 if (INTEGRAL_TYPE_P (TREE_TYPE (value)) 3813 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))) 3814 { 3815 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0), 3816 endtype); 3817 if (inner == null_pointer_node) 3818 return null_pointer_node; 3819 break; 3820 } 3821 3822 /* Allow (int) &foo provided int is as wide as a pointer. */ 3823 if (INTEGRAL_TYPE_P (TREE_TYPE (value)) 3824 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))) 3825 && (TYPE_PRECISION (TREE_TYPE (value)) 3826 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))) 3827 return initializer_constant_valid_p (TREE_OPERAND (value, 0), 3828 endtype); 3829 3830 /* Likewise conversions from int to pointers, but also allow 3831 conversions from 0. */ 3832 if (POINTER_TYPE_P (TREE_TYPE (value)) 3833 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))) 3834 { 3835 if (integer_zerop (TREE_OPERAND (value, 0))) 3836 return null_pointer_node; 3837 else if (TYPE_PRECISION (TREE_TYPE (value)) 3838 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))) 3839 return initializer_constant_valid_p (TREE_OPERAND (value, 0), 3840 endtype); 3841 } 3842 3843 /* Allow conversions to union types if the value inside is okay. */ 3844 if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE) 3845 return initializer_constant_valid_p (TREE_OPERAND (value, 0), 3846 endtype); 3847 break; 3848 3849 case PLUS_EXPR: 3850 if (! INTEGRAL_TYPE_P (endtype) 3851 || TYPE_PRECISION (endtype) >= POINTER_SIZE) 3852 { 3853 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0), 3854 endtype); 3855 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1), 3856 endtype); 3857 /* If either term is absolute, use the other terms relocation. */ 3858 if (valid0 == null_pointer_node) 3859 return valid1; 3860 if (valid1 == null_pointer_node) 3861 return valid0; 3862 } 3863 break; 3864 3865 case MINUS_EXPR: 3866 if (! INTEGRAL_TYPE_P (endtype) 3867 || TYPE_PRECISION (endtype) >= POINTER_SIZE) 3868 { 3869 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0), 3870 endtype); 3871 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1), 3872 endtype); 3873 /* Win if second argument is absolute. */ 3874 if (valid1 == null_pointer_node) 3875 return valid0; 3876 /* Win if both arguments have the same relocation. 3877 Then the value is absolute. */ 3878 if (valid0 == valid1 && valid0 != 0) 3879 return null_pointer_node; 3880 3881 /* Since GCC guarantees that string constants are unique in the 3882 generated code, a subtraction between two copies of the same 3883 constant string is absolute. */ 3884 if (valid0 && TREE_CODE (valid0) == STRING_CST && 3885 valid1 && TREE_CODE (valid1) == STRING_CST && 3886 TREE_STRING_POINTER (valid0) == TREE_STRING_POINTER (valid1)) 3887 return null_pointer_node; 3888 } 3889 3890 /* Support differences between labels. */ 3891 if (INTEGRAL_TYPE_P (endtype)) 3892 { 3893 tree op0, op1; 3894 op0 = TREE_OPERAND (value, 0); 3895 op1 = TREE_OPERAND (value, 1); 3896 3897 /* Like STRIP_NOPS except allow the operand mode to widen. 3898 This works around a feature of fold that simplfies 3899 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory 3900 that the narrower operation is cheaper. */ 3901 3902 while (TREE_CODE (op0) == NOP_EXPR 3903 || TREE_CODE (op0) == CONVERT_EXPR 3904 || TREE_CODE (op0) == NON_LVALUE_EXPR) 3905 { 3906 tree inner = TREE_OPERAND (op0, 0); 3907 if (inner == error_mark_node 3908 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner))) 3909 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))) 3910 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner))))) 3911 break; 3912 op0 = inner; 3913 } 3914 3915 while (TREE_CODE (op1) == NOP_EXPR 3916 || TREE_CODE (op1) == CONVERT_EXPR 3917 || TREE_CODE (op1) == NON_LVALUE_EXPR) 3918 { 3919 tree inner = TREE_OPERAND (op1, 0); 3920 if (inner == error_mark_node 3921 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner))) 3922 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1))) 3923 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner))))) 3924 break; 3925 op1 = inner; 3926 } 3927 3928 if (TREE_CODE (op0) == ADDR_EXPR 3929 && TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL 3930 && TREE_CODE (op1) == ADDR_EXPR 3931 && TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL) 3932 return null_pointer_node; 3933 } 3934 break; 3935 3936 default: 3937 break; 3938 } 3939 3940 return 0; 3941} 3942 3943/* Output assembler code for constant EXP to FILE, with no label. 3944 This includes the pseudo-op such as ".int" or ".byte", and a newline. 3945 Assumes output_addressed_constants has been done on EXP already. 3946 3947 Generate exactly SIZE bytes of assembler data, padding at the end 3948 with zeros if necessary. SIZE must always be specified. 3949 3950 SIZE is important for structure constructors, 3951 since trailing members may have been omitted from the constructor. 3952 It is also important for initialization of arrays from string constants 3953 since the full length of the string constant might not be wanted. 3954 It is also needed for initialization of unions, where the initializer's 3955 type is just one member, and that may not be as long as the union. 3956 3957 There a case in which we would fail to output exactly SIZE bytes: 3958 for a structure constructor that wants to produce more than SIZE bytes. 3959 But such constructors will never be generated for any possible input. 3960 3961 ALIGN is the alignment of the data in bits. */ 3962 3963void 3964output_constant (exp, size, align) 3965 tree exp; 3966 HOST_WIDE_INT size; 3967 unsigned int align; 3968{ 3969 enum tree_code code; 3970 HOST_WIDE_INT thissize; 3971 3972 /* Some front-ends use constants other than the standard language-indepdent 3973 varieties, but which may still be output directly. Give the front-end a 3974 chance to convert EXP to a language-independent representation. */ 3975 exp = (*lang_hooks.expand_constant) (exp); 3976 3977 if (size == 0 || flag_syntax_only) 3978 return; 3979 3980 /* Eliminate any conversions since we'll be outputting the underlying 3981 constant. */ 3982 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR 3983 || TREE_CODE (exp) == NON_LVALUE_EXPR 3984 || TREE_CODE (exp) == VIEW_CONVERT_EXPR) 3985 exp = TREE_OPERAND (exp, 0); 3986 3987 code = TREE_CODE (TREE_TYPE (exp)); 3988 thissize = int_size_in_bytes (TREE_TYPE (exp)); 3989 3990 /* Allow a constructor with no elements for any data type. 3991 This means to fill the space with zeros. */ 3992 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0) 3993 { 3994 assemble_zeros (size); 3995 return; 3996 } 3997 3998 if (TREE_CODE (exp) == FDESC_EXPR) 3999 { 4000#ifdef ASM_OUTPUT_FDESC 4001 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0); 4002 tree decl = TREE_OPERAND (exp, 0); 4003 ASM_OUTPUT_FDESC (asm_out_file, decl, part); 4004#else 4005 abort (); 4006#endif 4007 return; 4008 } 4009 4010 /* Now output the underlying data. If we've handling the padding, return. 4011 Otherwise, break and ensure THISSIZE is the size written. */ 4012 switch (code) 4013 { 4014 case CHAR_TYPE: 4015 case BOOLEAN_TYPE: 4016 case INTEGER_TYPE: 4017 case ENUMERAL_TYPE: 4018 case POINTER_TYPE: 4019 case REFERENCE_TYPE: 4020 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode, 4021 EXPAND_INITIALIZER), 4022 size, align, 0)) 4023 error ("initializer for integer value is too complicated"); 4024 break; 4025 4026 case REAL_TYPE: 4027 if (TREE_CODE (exp) != REAL_CST) 4028 error ("initializer for floating value is not a floating constant"); 4029 4030 assemble_real (TREE_REAL_CST (exp), 4031 mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0), 4032 align); 4033 break; 4034 4035 case COMPLEX_TYPE: 4036 output_constant (TREE_REALPART (exp), thissize / 2, align); 4037 output_constant (TREE_IMAGPART (exp), thissize / 2, 4038 min_align (align, BITS_PER_UNIT * (thissize / 2))); 4039 break; 4040 4041 case ARRAY_TYPE: 4042 case VECTOR_TYPE: 4043 if (TREE_CODE (exp) == CONSTRUCTOR) 4044 { 4045 output_constructor (exp, size, align); 4046 return; 4047 } 4048 else if (TREE_CODE (exp) == STRING_CST) 4049 { 4050 thissize = MIN (TREE_STRING_LENGTH (exp), size); 4051 assemble_string (TREE_STRING_POINTER (exp), thissize); 4052 } 4053 else 4054 abort (); 4055 break; 4056 4057 case RECORD_TYPE: 4058 case UNION_TYPE: 4059 if (TREE_CODE (exp) == CONSTRUCTOR) 4060 output_constructor (exp, size, align); 4061 else 4062 abort (); 4063 return; 4064 4065 case SET_TYPE: 4066 if (TREE_CODE (exp) == INTEGER_CST) 4067 assemble_integer (expand_expr (exp, NULL_RTX, 4068 VOIDmode, EXPAND_INITIALIZER), 4069 thissize, align, 1); 4070 else if (TREE_CODE (exp) == CONSTRUCTOR) 4071 { 4072 unsigned char *buffer = (unsigned char *) alloca (thissize); 4073 if (get_set_constructor_bytes (exp, buffer, thissize)) 4074 abort (); 4075 assemble_string ((char *) buffer, thissize); 4076 } 4077 else 4078 error ("unknown set constructor type"); 4079 return; 4080 4081 case ERROR_MARK: 4082 return; 4083 4084 default: 4085 abort (); 4086 } 4087 4088 size -= thissize; 4089 if (size > 0) 4090 assemble_zeros (size); 4091} 4092 4093 4094/* Subroutine of output_constructor, used for computing the size of 4095 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array 4096 type with an unspecified upper bound. */ 4097 4098static unsigned HOST_WIDE_INT 4099array_size_for_constructor (val) 4100 tree val; 4101{ 4102 tree max_index, i; 4103 4104 /* This code used to attempt to handle string constants that are not 4105 arrays of single-bytes, but nothing else does, so there's no point in 4106 doing it here. */ 4107 if (TREE_CODE (val) == STRING_CST) 4108 return TREE_STRING_LENGTH (val); 4109 4110 max_index = NULL_TREE; 4111 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i)) 4112 { 4113 tree index = TREE_PURPOSE (i); 4114 4115 if (TREE_CODE (index) == RANGE_EXPR) 4116 index = TREE_OPERAND (index, 1); 4117 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index)) 4118 max_index = index; 4119 } 4120 4121 if (max_index == NULL_TREE) 4122 return 0; 4123 4124 /* Compute the total number of array elements. */ 4125 i = size_binop (MINUS_EXPR, convert (sizetype, max_index), 4126 convert (sizetype, 4127 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val))))); 4128 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node)); 4129 4130 /* Multiply by the array element unit size to find number of bytes. */ 4131 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val)))); 4132 4133 return tree_low_cst (i, 1); 4134} 4135 4136/* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants). 4137 Generate at least SIZE bytes, padding if necessary. */ 4138 4139static void 4140output_constructor (exp, size, align) 4141 tree exp; 4142 HOST_WIDE_INT size; 4143 unsigned int align; 4144{ 4145 tree type = TREE_TYPE (exp); 4146 tree link, field = 0; 4147 tree min_index = 0; 4148 /* Number of bytes output or skipped so far. 4149 In other words, current position within the constructor. */ 4150 HOST_WIDE_INT total_bytes = 0; 4151 /* Non-zero means BYTE contains part of a byte, to be output. */ 4152 int byte_buffer_in_use = 0; 4153 int byte = 0; 4154 4155 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT) 4156 abort (); 4157 4158 if (TREE_CODE (type) == RECORD_TYPE) 4159 field = TYPE_FIELDS (type); 4160 4161 if (TREE_CODE (type) == ARRAY_TYPE 4162 && TYPE_DOMAIN (type) != 0) 4163 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type)); 4164 4165 /* As LINK goes through the elements of the constant, 4166 FIELD goes through the structure fields, if the constant is a structure. 4167 if the constant is a union, then we override this, 4168 by getting the field from the TREE_LIST element. 4169 But the constant could also be an array. Then FIELD is zero. 4170 4171 There is always a maximum of one element in the chain LINK for unions 4172 (even if the initializer in a source program incorrectly contains 4173 more one). */ 4174 for (link = CONSTRUCTOR_ELTS (exp); 4175 link; 4176 link = TREE_CHAIN (link), 4177 field = field ? TREE_CHAIN (field) : 0) 4178 { 4179 tree val = TREE_VALUE (link); 4180 tree index = 0; 4181 4182 /* The element in a union constructor specifies the proper field 4183 or index. */ 4184 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE 4185 || TREE_CODE (type) == QUAL_UNION_TYPE) 4186 && TREE_PURPOSE (link) != 0) 4187 field = TREE_PURPOSE (link); 4188 4189 else if (TREE_CODE (type) == ARRAY_TYPE) 4190 index = TREE_PURPOSE (link); 4191 4192 /* Eliminate the marker that makes a cast not be an lvalue. */ 4193 if (val != 0) 4194 STRIP_NOPS (val); 4195 4196 if (index && TREE_CODE (index) == RANGE_EXPR) 4197 { 4198 unsigned HOST_WIDE_INT fieldsize 4199 = int_size_in_bytes (TREE_TYPE (type)); 4200 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0); 4201 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0); 4202 HOST_WIDE_INT index; 4203 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT); 4204 4205 for (index = lo_index; index <= hi_index; index++) 4206 { 4207 /* Output the element's initial value. */ 4208 if (val == 0) 4209 assemble_zeros (fieldsize); 4210 else 4211 output_constant (val, fieldsize, align2); 4212 4213 /* Count its size. */ 4214 total_bytes += fieldsize; 4215 } 4216 } 4217 else if (field == 0 || !DECL_BIT_FIELD (field)) 4218 { 4219 /* An element that is not a bit-field. */ 4220 4221 unsigned HOST_WIDE_INT fieldsize; 4222 /* Since this structure is static, 4223 we know the positions are constant. */ 4224 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0; 4225 unsigned int align2; 4226 4227 if (index != 0) 4228 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1) 4229 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0))); 4230 4231 /* Output any buffered-up bit-fields preceding this element. */ 4232 if (byte_buffer_in_use) 4233 { 4234 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1); 4235 total_bytes++; 4236 byte_buffer_in_use = 0; 4237 } 4238 4239 /* Advance to offset of this element. 4240 Note no alignment needed in an array, since that is guaranteed 4241 if each element has the proper size. */ 4242 if ((field != 0 || index != 0) && pos != total_bytes) 4243 { 4244 assemble_zeros (pos - total_bytes); 4245 total_bytes = pos; 4246 } 4247 4248 /* Find the alignment of this element. */ 4249 align2 = min_align (align, BITS_PER_UNIT * pos); 4250 4251 /* Determine size this element should occupy. */ 4252 if (field) 4253 { 4254 fieldsize = 0; 4255 4256 /* If this is an array with an unspecified upper bound, 4257 the initializer determines the size. */ 4258 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL, 4259 but we cannot do this until the deprecated support for 4260 initializing zero-length array members is removed. */ 4261 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE 4262 && TYPE_DOMAIN (TREE_TYPE (field)) 4263 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field)))) 4264 { 4265 fieldsize = array_size_for_constructor (val); 4266 /* Given a non-empty initialization, this field had 4267 better be last. */ 4268 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE) 4269 abort (); 4270 } 4271 else if (DECL_SIZE_UNIT (field)) 4272 { 4273 /* ??? This can't be right. If the decl size overflows 4274 a host integer we will silently emit no data. */ 4275 if (host_integerp (DECL_SIZE_UNIT (field), 1)) 4276 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1); 4277 } 4278 } 4279 else 4280 fieldsize = int_size_in_bytes (TREE_TYPE (type)); 4281 4282 /* Output the element's initial value. */ 4283 if (val == 0) 4284 assemble_zeros (fieldsize); 4285 else 4286 output_constant (val, fieldsize, align2); 4287 4288 /* Count its size. */ 4289 total_bytes += fieldsize; 4290 } 4291 else if (val != 0 && TREE_CODE (val) != INTEGER_CST) 4292 error ("invalid initial value for member `%s'", 4293 IDENTIFIER_POINTER (DECL_NAME (field))); 4294 else 4295 { 4296 /* Element that is a bit-field. */ 4297 4298 HOST_WIDE_INT next_offset = int_bit_position (field); 4299 HOST_WIDE_INT end_offset 4300 = (next_offset + tree_low_cst (DECL_SIZE (field), 1)); 4301 4302 if (val == 0) 4303 val = integer_zero_node; 4304 4305 /* If this field does not start in this (or, next) byte, 4306 skip some bytes. */ 4307 if (next_offset / BITS_PER_UNIT != total_bytes) 4308 { 4309 /* Output remnant of any bit field in previous bytes. */ 4310 if (byte_buffer_in_use) 4311 { 4312 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1); 4313 total_bytes++; 4314 byte_buffer_in_use = 0; 4315 } 4316 4317 /* If still not at proper byte, advance to there. */ 4318 if (next_offset / BITS_PER_UNIT != total_bytes) 4319 { 4320 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes); 4321 total_bytes = next_offset / BITS_PER_UNIT; 4322 } 4323 } 4324 4325 if (! byte_buffer_in_use) 4326 byte = 0; 4327 4328 /* We must split the element into pieces that fall within 4329 separate bytes, and combine each byte with previous or 4330 following bit-fields. */ 4331 4332 /* next_offset is the offset n fbits from the beginning of 4333 the structure to the next bit of this element to be processed. 4334 end_offset is the offset of the first bit past the end of 4335 this element. */ 4336 while (next_offset < end_offset) 4337 { 4338 int this_time; 4339 int shift; 4340 HOST_WIDE_INT value; 4341 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT; 4342 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT; 4343 4344 /* Advance from byte to byte 4345 within this element when necessary. */ 4346 while (next_byte != total_bytes) 4347 { 4348 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1); 4349 total_bytes++; 4350 byte = 0; 4351 } 4352 4353 /* Number of bits we can process at once 4354 (all part of the same byte). */ 4355 this_time = MIN (end_offset - next_offset, 4356 BITS_PER_UNIT - next_bit); 4357 if (BYTES_BIG_ENDIAN) 4358 { 4359 /* On big-endian machine, take the most significant bits 4360 first (of the bits that are significant) 4361 and put them into bytes from the most significant end. */ 4362 shift = end_offset - next_offset - this_time; 4363 4364 /* Don't try to take a bunch of bits that cross 4365 the word boundary in the INTEGER_CST. We can 4366 only select bits from the LOW or HIGH part 4367 not from both. */ 4368 if (shift < HOST_BITS_PER_WIDE_INT 4369 && shift + this_time > HOST_BITS_PER_WIDE_INT) 4370 { 4371 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT; 4372 shift = HOST_BITS_PER_WIDE_INT; 4373 } 4374 4375 /* Now get the bits from the appropriate constant word. */ 4376 if (shift < HOST_BITS_PER_WIDE_INT) 4377 value = TREE_INT_CST_LOW (val); 4378 else if (shift < 2 * HOST_BITS_PER_WIDE_INT) 4379 { 4380 value = TREE_INT_CST_HIGH (val); 4381 shift -= HOST_BITS_PER_WIDE_INT; 4382 } 4383 else 4384 abort (); 4385 4386 /* Get the result. This works only when: 4387 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */ 4388 byte |= (((value >> shift) 4389 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1)) 4390 << (BITS_PER_UNIT - this_time - next_bit)); 4391 } 4392 else 4393 { 4394 /* On little-endian machines, 4395 take first the least significant bits of the value 4396 and pack them starting at the least significant 4397 bits of the bytes. */ 4398 shift = next_offset - int_bit_position (field); 4399 4400 /* Don't try to take a bunch of bits that cross 4401 the word boundary in the INTEGER_CST. We can 4402 only select bits from the LOW or HIGH part 4403 not from both. */ 4404 if (shift < HOST_BITS_PER_WIDE_INT 4405 && shift + this_time > HOST_BITS_PER_WIDE_INT) 4406 this_time = (HOST_BITS_PER_WIDE_INT - shift); 4407 4408 /* Now get the bits from the appropriate constant word. */ 4409 if (shift < HOST_BITS_PER_WIDE_INT) 4410 value = TREE_INT_CST_LOW (val); 4411 else if (shift < 2 * HOST_BITS_PER_WIDE_INT) 4412 { 4413 value = TREE_INT_CST_HIGH (val); 4414 shift -= HOST_BITS_PER_WIDE_INT; 4415 } 4416 else 4417 abort (); 4418 4419 /* Get the result. This works only when: 4420 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */ 4421 byte |= (((value >> shift) 4422 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1)) 4423 << next_bit); 4424 } 4425 4426 next_offset += this_time; 4427 byte_buffer_in_use = 1; 4428 } 4429 } 4430 } 4431 4432 if (byte_buffer_in_use) 4433 { 4434 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1); 4435 total_bytes++; 4436 } 4437 4438 if (total_bytes < size) 4439 assemble_zeros (size - total_bytes); 4440} 4441 4442/* This TREE_LIST contains any weak symbol declarations waiting 4443 to be emitted. */ 4444static GTY(()) tree weak_decls; 4445 4446/* Mark DECL as weak. */ 4447 4448static void 4449mark_weak (decl) 4450 tree decl; 4451{ 4452 DECL_WEAK (decl) = 1; 4453 4454 if (DECL_RTL_SET_P (decl) 4455 && GET_CODE (DECL_RTL (decl)) == MEM 4456 && XEXP (DECL_RTL (decl), 0) 4457 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF) 4458 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1; 4459} 4460 4461/* Merge weak status between NEWDECL and OLDDECL. */ 4462 4463void 4464merge_weak (newdecl, olddecl) 4465 tree newdecl; 4466 tree olddecl; 4467{ 4468 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl)) 4469 return; 4470 4471 if (DECL_WEAK (newdecl)) 4472 { 4473 tree wd; 4474 4475 /* NEWDECL is weak, but OLDDECL is not. */ 4476 4477 /* If we already output the OLDDECL, we're in trouble; we can't 4478 go back and make it weak. This error cannot caught in 4479 declare_weak because the NEWDECL and OLDDECL was not yet 4480 been merged; therefore, TREE_ASM_WRITTEN was not set. */ 4481 if (TREE_ASM_WRITTEN (olddecl)) 4482 error_with_decl (newdecl, 4483 "weak declaration of `%s' must precede definition"); 4484 4485 /* If we've already generated rtl referencing OLDDECL, we may 4486 have done so in a way that will not function properly with 4487 a weak symbol. */ 4488 else if (TREE_USED (olddecl) 4489 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl))) 4490 warning_with_decl (newdecl, "weak declaration of `%s' after first use results in unspecified behavior"); 4491 4492 if (SUPPORTS_WEAK) 4493 { 4494 /* We put the NEWDECL on the weak_decls list at some point. 4495 Replace it with the OLDDECL. */ 4496 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd)) 4497 if (TREE_VALUE (wd) == newdecl) 4498 { 4499 TREE_VALUE (wd) = olddecl; 4500 break; 4501 } 4502 /* We may not find the entry on the list. If NEWDECL is a 4503 weak alias, then we will have already called 4504 globalize_decl to remove the entry; in that case, we do 4505 not need to do anything. */ 4506 } 4507 4508 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */ 4509 mark_weak (olddecl); 4510 } 4511 else 4512 /* OLDDECL was weak, but NEWDECL was not explicitly marked as 4513 weak. Just update NEWDECL to indicate that it's weak too. */ 4514 mark_weak (newdecl); 4515} 4516 4517/* Declare DECL to be a weak symbol. */ 4518 4519void 4520declare_weak (decl) 4521 tree decl; 4522{ 4523 if (! TREE_PUBLIC (decl)) 4524 error_with_decl (decl, "weak declaration of `%s' must be public"); 4525 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl)) 4526 error_with_decl (decl, "weak declaration of `%s' must precede definition"); 4527 else if (SUPPORTS_WEAK) 4528 { 4529 if (! DECL_WEAK (decl)) 4530 weak_decls = tree_cons (NULL, decl, weak_decls); 4531 } 4532 else 4533 warning_with_decl (decl, "weak declaration of `%s' not supported"); 4534 4535 mark_weak (decl); 4536} 4537 4538/* Emit any pending weak declarations. */ 4539 4540void 4541weak_finish () 4542{ 4543 tree t; 4544 4545 for (t = weak_decls; t; t = TREE_CHAIN (t)) 4546 { 4547 tree decl = TREE_VALUE (t); 4548 const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 4549 4550 if (! TREE_USED (decl)) 4551 continue; 4552 4553#ifdef ASM_WEAKEN_DECL 4554 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL); 4555#else 4556#ifdef ASM_WEAKEN_LABEL 4557 ASM_WEAKEN_LABEL (asm_out_file, name); 4558#else 4559#ifdef ASM_OUTPUT_WEAK_ALIAS 4560 warning ("only weak aliases are supported in this configuration"); 4561 return; 4562#endif 4563#endif 4564#endif 4565 } 4566} 4567 4568/* Emit the assembly bits to indicate that DECL is globally visible. */ 4569 4570static void 4571globalize_decl (decl) 4572 tree decl; 4573{ 4574 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 4575 4576#if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL) 4577 if (DECL_WEAK (decl)) 4578 { 4579 tree *p, t; 4580 4581#ifdef ASM_WEAKEN_DECL 4582 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0); 4583#else 4584 ASM_WEAKEN_LABEL (asm_out_file, name); 4585#endif 4586 4587 /* Remove this function from the pending weak list so that 4588 we do not emit multiple .weak directives for it. */ 4589 for (p = &weak_decls; (t = *p) ; ) 4590 { 4591 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))) 4592 *p = TREE_CHAIN (t); 4593 else 4594 p = &TREE_CHAIN (t); 4595 } 4596 return; 4597 } 4598#endif 4599 4600 (*targetm.asm_out.globalize_label) (asm_out_file, name); 4601} 4602 4603/* Emit an assembler directive to make the symbol for DECL an alias to 4604 the symbol for TARGET. */ 4605 4606void 4607assemble_alias (decl, target) 4608 tree decl, target ATTRIBUTE_UNUSED; 4609{ 4610 const char *name; 4611 4612 /* We must force creation of DECL_RTL for debug info generation, even though 4613 we don't use it here. */ 4614 make_decl_rtl (decl, NULL); 4615 4616 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 4617 4618#ifdef ASM_OUTPUT_DEF 4619 /* Make name accessible from other files, if appropriate. */ 4620 4621 if (TREE_PUBLIC (decl)) 4622 { 4623 globalize_decl (decl); 4624 maybe_assemble_visibility (decl); 4625 } 4626 4627#ifdef ASM_OUTPUT_DEF_FROM_DECLS 4628 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target); 4629#else 4630 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target)); 4631#endif 4632#else /* !ASM_OUTPUT_DEF */ 4633#if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL) 4634 if (! DECL_WEAK (decl)) 4635 warning ("only weak aliases are supported in this configuration"); 4636 4637#ifdef ASM_WEAKEN_DECL 4638 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target)); 4639#else 4640 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target)); 4641#endif 4642#else 4643 warning ("alias definitions not supported in this configuration; ignored"); 4644#endif 4645#endif 4646 4647 TREE_USED (decl) = 1; 4648 TREE_ASM_WRITTEN (decl) = 1; 4649 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1; 4650} 4651 4652/* Emit an assembler directive to set symbol for DECL visibility to 4653 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */ 4654 4655void 4656default_assemble_visibility (decl, vis) 4657 tree decl; 4658 int vis; 4659{ 4660 static const char * const visibility_types[] = { 4661 NULL, "internal", "hidden", "protected" 4662 }; 4663 4664 const char *name, *type; 4665 4666 name = (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl))); 4667 type = visibility_types[vis]; 4668 4669#ifdef HAVE_GAS_HIDDEN 4670 fprintf (asm_out_file, "\t.%s\t", type); 4671 assemble_name (asm_out_file, name); 4672 fprintf (asm_out_file, "\n"); 4673#else 4674 warning ("visibility attribute not supported in this configuration; ignored"); 4675#endif 4676} 4677 4678/* A helper function to call assemble_visibility when needed for a decl. */ 4679 4680static void 4681maybe_assemble_visibility (decl) 4682 tree decl; 4683{ 4684 enum symbol_visibility vis = decl_visibility (decl); 4685 4686 if (vis != VISIBILITY_DEFAULT) 4687 (* targetm.asm_out.visibility) (decl, vis); 4688} 4689 4690/* Returns 1 if the target configuration supports defining public symbols 4691 so that one of them will be chosen at link time instead of generating a 4692 multiply-defined symbol error, whether through the use of weak symbols or 4693 a target-specific mechanism for having duplicates discarded. */ 4694 4695int 4696supports_one_only () 4697{ 4698 if (SUPPORTS_ONE_ONLY) 4699 return 1; 4700 return SUPPORTS_WEAK; 4701} 4702 4703/* Set up DECL as a public symbol that can be defined in multiple 4704 translation units without generating a linker error. */ 4705 4706void 4707make_decl_one_only (decl) 4708 tree decl; 4709{ 4710 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL) 4711 abort (); 4712 4713 TREE_PUBLIC (decl) = 1; 4714 4715 if (TREE_CODE (decl) == VAR_DECL 4716 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node)) 4717 DECL_COMMON (decl) = 1; 4718 else if (SUPPORTS_ONE_ONLY) 4719 { 4720#ifdef MAKE_DECL_ONE_ONLY 4721 MAKE_DECL_ONE_ONLY (decl); 4722#endif 4723 DECL_ONE_ONLY (decl) = 1; 4724 } 4725 else if (SUPPORTS_WEAK) 4726 DECL_WEAK (decl) = 1; 4727 else 4728 abort (); 4729} 4730 4731void 4732init_varasm_once () 4733{ 4734 const_str_htab = htab_create_ggc (128, const_str_htab_hash, 4735 const_str_htab_eq, NULL); 4736 in_named_htab = htab_create (31, in_named_entry_hash, 4737 in_named_entry_eq, NULL); 4738 4739 const_alias_set = new_alias_set (); 4740} 4741 4742enum tls_model 4743decl_tls_model (decl) 4744 tree decl; 4745{ 4746 enum tls_model kind; 4747 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl)); 4748 bool is_local; 4749 4750 if (attr) 4751 { 4752 attr = TREE_VALUE (TREE_VALUE (attr)); 4753 if (TREE_CODE (attr) != STRING_CST) 4754 abort (); 4755 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec")) 4756 kind = TLS_MODEL_LOCAL_EXEC; 4757 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec")) 4758 kind = TLS_MODEL_INITIAL_EXEC; 4759 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic")) 4760 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC; 4761 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic")) 4762 kind = TLS_MODEL_GLOBAL_DYNAMIC; 4763 else 4764 abort (); 4765 return kind; 4766 } 4767 4768 is_local = (*targetm.binds_local_p) (decl); 4769 if (!flag_pic) 4770 { 4771 if (is_local) 4772 kind = TLS_MODEL_LOCAL_EXEC; 4773 else 4774 kind = TLS_MODEL_INITIAL_EXEC; 4775 } 4776 /* Local dynamic is inefficient when we're not combining the 4777 parts of the address. */ 4778 else if (optimize && is_local) 4779 kind = TLS_MODEL_LOCAL_DYNAMIC; 4780 else 4781 kind = TLS_MODEL_GLOBAL_DYNAMIC; 4782 if (kind < flag_tls_default) 4783 kind = flag_tls_default; 4784 4785 return kind; 4786} 4787 4788enum symbol_visibility 4789decl_visibility (decl) 4790 tree decl; 4791{ 4792 tree attr = lookup_attribute ("visibility", DECL_ATTRIBUTES (decl)); 4793 4794 if (attr) 4795 { 4796 const char *which = TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr))); 4797 4798 if (strcmp (which, "default") == 0) 4799 return VISIBILITY_DEFAULT; 4800 if (strcmp (which, "internal") == 0) 4801 return VISIBILITY_INTERNAL; 4802 if (strcmp (which, "hidden") == 0) 4803 return VISIBILITY_HIDDEN; 4804 if (strcmp (which, "protected") == 0) 4805 return VISIBILITY_PROTECTED; 4806 4807 abort (); 4808 } 4809 4810 return VISIBILITY_DEFAULT; 4811} 4812 4813/* Select a set of attributes for section NAME based on the properties 4814 of DECL and whether or not RELOC indicates that DECL's initializer 4815 might contain runtime relocations. 4816 4817 We make the section read-only and executable for a function decl, 4818 read-only for a const data decl, and writable for a non-const data decl. */ 4819 4820unsigned int 4821default_section_type_flags (decl, name, reloc) 4822 tree decl; 4823 const char *name; 4824 int reloc; 4825{ 4826 return default_section_type_flags_1 (decl, name, reloc, flag_pic); 4827} 4828 4829unsigned int 4830default_section_type_flags_1 (decl, name, reloc, shlib) 4831 tree decl; 4832 const char *name; 4833 int reloc; 4834 int shlib; 4835{ 4836 unsigned int flags; 4837 4838 if (decl && TREE_CODE (decl) == FUNCTION_DECL) 4839 flags = SECTION_CODE; 4840 else if (decl && decl_readonly_section_1 (decl, reloc, shlib)) 4841 flags = 0; 4842 else 4843 flags = SECTION_WRITE; 4844 4845 if (decl && DECL_ONE_ONLY (decl)) 4846 flags |= SECTION_LINKONCE; 4847 4848 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl)) 4849 flags |= SECTION_TLS | SECTION_WRITE; 4850 4851 if (strcmp (name, ".bss") == 0 4852 || strncmp (name, ".bss.", 5) == 0 4853 || strncmp (name, ".gnu.linkonce.b.", 16) == 0 4854 || strcmp (name, ".sbss") == 0 4855 || strncmp (name, ".sbss.", 6) == 0 4856 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0 4857 || strcmp (name, ".tbss") == 0 4858 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0) 4859 flags |= SECTION_BSS; 4860 4861 if (strcmp (name, ".tdata") == 0 4862 || strcmp (name, ".tbss") == 0 4863 || strncmp (name, ".gnu.linkonce.td.", 17) == 0 4864 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0) 4865 flags |= SECTION_TLS; 4866 4867 /* These three sections have special ELF types. They are neither 4868 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't 4869 want to print a section type (@progbits or @nobits). If someone 4870 is silly enough to emit code or TLS variables to one of these 4871 sections, then don't handle them specially. */ 4872 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS)) 4873 && (strcmp (name, ".init_array") == 0 4874 || strcmp (name, ".fini_array") == 0 4875 || strcmp (name, ".preinit_array") == 0)) 4876 flags |= SECTION_NOTYPE; 4877 4878 return flags; 4879} 4880 4881/* Output assembly to switch to section NAME with attribute FLAGS. 4882 Four variants for common object file formats. */ 4883 4884void 4885default_no_named_section (name, flags) 4886 const char *name ATTRIBUTE_UNUSED; 4887 unsigned int flags ATTRIBUTE_UNUSED; 4888{ 4889 /* Some object formats don't support named sections at all. The 4890 front-end should already have flagged this as an error. */ 4891 abort (); 4892} 4893 4894void 4895default_elf_asm_named_section (name, flags) 4896 const char *name; 4897 unsigned int flags; 4898{ 4899 char flagchars[10], *f = flagchars; 4900 4901 if (! named_section_first_declaration (name)) 4902 { 4903 fprintf (asm_out_file, "\t.section\t%s\n", name); 4904 return; 4905 } 4906 4907 if (!(flags & SECTION_DEBUG)) 4908 *f++ = 'a'; 4909 if (flags & SECTION_WRITE) 4910 *f++ = 'w'; 4911 if (flags & SECTION_CODE) 4912 *f++ = 'x'; 4913 if (flags & SECTION_SMALL) 4914 *f++ = 's'; 4915 if (flags & SECTION_MERGE) 4916 *f++ = 'M'; 4917 if (flags & SECTION_STRINGS) 4918 *f++ = 'S'; 4919 if (flags & SECTION_TLS) 4920 *f++ = 'T'; 4921 *f = '\0'; 4922 4923 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars); 4924 4925 if (!(flags & SECTION_NOTYPE)) 4926 { 4927 const char *type; 4928 4929 if (flags & SECTION_BSS) 4930 type = "nobits"; 4931 else 4932 type = "progbits"; 4933 4934 fprintf (asm_out_file, ",@%s", type); 4935 4936 if (flags & SECTION_ENTSIZE) 4937 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE); 4938 } 4939 4940 putc ('\n', asm_out_file); 4941} 4942 4943void 4944default_coff_asm_named_section (name, flags) 4945 const char *name; 4946 unsigned int flags; 4947{ 4948 char flagchars[8], *f = flagchars; 4949 4950 if (flags & SECTION_WRITE) 4951 *f++ = 'w'; 4952 if (flags & SECTION_CODE) 4953 *f++ = 'x'; 4954 *f = '\0'; 4955 4956 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars); 4957} 4958 4959void 4960default_pe_asm_named_section (name, flags) 4961 const char *name; 4962 unsigned int flags; 4963{ 4964 default_coff_asm_named_section (name, flags); 4965 4966 if (flags & SECTION_LINKONCE) 4967 { 4968 /* Functions may have been compiled at various levels of 4969 optimization so we can't use `same_size' here. 4970 Instead, have the linker pick one. */ 4971 fprintf (asm_out_file, "\t.linkonce %s\n", 4972 (flags & SECTION_CODE ? "discard" : "same_size")); 4973 } 4974} 4975 4976/* Used for vtable gc in GNU binutils. Record that the pointer at OFFSET 4977 from SYMBOL is used in all classes derived from SYMBOL. */ 4978 4979void 4980assemble_vtable_entry (symbol, offset) 4981 rtx symbol; 4982 HOST_WIDE_INT offset; 4983{ 4984 fputs ("\t.vtable_entry ", asm_out_file); 4985 output_addr_const (asm_out_file, symbol); 4986 fputs (", ", asm_out_file); 4987 fprintf (asm_out_file, HOST_WIDE_INT_PRINT_DEC, offset); 4988 fputc ('\n', asm_out_file); 4989} 4990 4991/* Used for vtable gc in GNU binutils. Record the class hierarchy by noting 4992 that the vtable symbol CHILD is derived from the vtable symbol PARENT. */ 4993 4994void 4995assemble_vtable_inherit (child, parent) 4996 rtx child, parent; 4997{ 4998 fputs ("\t.vtable_inherit ", asm_out_file); 4999 output_addr_const (asm_out_file, child); 5000 fputs (", ", asm_out_file); 5001 output_addr_const (asm_out_file, parent); 5002 fputc ('\n', asm_out_file); 5003} 5004 5005/* The lame default section selector. */ 5006 5007void 5008default_select_section (decl, reloc, align) 5009 tree decl; 5010 int reloc; 5011 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED; 5012{ 5013 bool readonly = false; 5014 5015 if (DECL_P (decl)) 5016 { 5017 if (decl_readonly_section (decl, reloc)) 5018 readonly = true; 5019 } 5020 else if (TREE_CODE (decl) == CONSTRUCTOR) 5021 { 5022 if (! ((flag_pic && reloc) 5023 || !TREE_READONLY (decl) 5024 || TREE_SIDE_EFFECTS (decl) 5025 || !TREE_CONSTANT (decl))) 5026 readonly = true; 5027 } 5028 else if (TREE_CODE (decl) == STRING_CST) 5029 readonly = !flag_writable_strings; 5030 else if (! (flag_pic && reloc)) 5031 readonly = true; 5032 5033 if (readonly) 5034 readonly_data_section (); 5035 else 5036 data_section (); 5037} 5038 5039/* A helper function for default_elf_select_section and 5040 default_elf_unique_section. Categorizes the DECL. */ 5041 5042enum section_category 5043{ 5044 SECCAT_TEXT, 5045 5046 SECCAT_RODATA, 5047 SECCAT_RODATA_MERGE_STR, 5048 SECCAT_RODATA_MERGE_STR_INIT, 5049 SECCAT_RODATA_MERGE_CONST, 5050 SECCAT_SRODATA, 5051 5052 SECCAT_DATA, 5053 5054 /* To optimize loading of shared programs, define following subsections 5055 of data section: 5056 _REL Contains data that has relocations, so they get grouped 5057 together and dynamic linker will visit fewer pages in memory. 5058 _RO Contains data that is otherwise read-only. This is useful 5059 with prelinking as most relocations won't be dynamically 5060 linked and thus stay read only. 5061 _LOCAL Marks data containing relocations only to local objects. 5062 These relocations will get fully resolved by prelinking. */ 5063 SECCAT_DATA_REL, 5064 SECCAT_DATA_REL_LOCAL, 5065 SECCAT_DATA_REL_RO, 5066 SECCAT_DATA_REL_RO_LOCAL, 5067 5068 SECCAT_SDATA, 5069 SECCAT_TDATA, 5070 5071 SECCAT_BSS, 5072 SECCAT_SBSS, 5073 SECCAT_TBSS 5074}; 5075 5076static enum section_category 5077categorize_decl_for_section PARAMS ((tree, int, int)); 5078 5079static enum section_category 5080categorize_decl_for_section (decl, reloc, shlib) 5081 tree decl; 5082 int reloc; 5083 int shlib; 5084{ 5085 enum section_category ret; 5086 5087 if (TREE_CODE (decl) == FUNCTION_DECL) 5088 return SECCAT_TEXT; 5089 else if (TREE_CODE (decl) == STRING_CST) 5090 { 5091 if (flag_writable_strings) 5092 return SECCAT_DATA; 5093 else 5094 return SECCAT_RODATA_MERGE_STR; 5095 } 5096 else if (TREE_CODE (decl) == VAR_DECL) 5097 { 5098 if (DECL_INITIAL (decl) == NULL 5099 || DECL_INITIAL (decl) == error_mark_node) 5100 ret = SECCAT_BSS; 5101 else if (! TREE_READONLY (decl) 5102 || TREE_SIDE_EFFECTS (decl) 5103 || ! TREE_CONSTANT (DECL_INITIAL (decl))) 5104 { 5105 if (shlib && (reloc & 2)) 5106 ret = SECCAT_DATA_REL; 5107 else if (shlib && reloc) 5108 ret = SECCAT_DATA_REL_LOCAL; 5109 else 5110 ret = SECCAT_DATA; 5111 } 5112 else if (shlib && (reloc & 2)) 5113 ret = SECCAT_DATA_REL_RO; 5114 else if (shlib && reloc) 5115 ret = SECCAT_DATA_REL_RO_LOCAL; 5116 else if (reloc || flag_merge_constants < 2) 5117 /* C and C++ don't allow different variables to share the same 5118 location. -fmerge-all-constants allows even that (at the 5119 expense of not conforming). */ 5120 ret = SECCAT_RODATA; 5121 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST) 5122 ret = SECCAT_RODATA_MERGE_STR_INIT; 5123 else 5124 ret = SECCAT_RODATA_MERGE_CONST; 5125 } 5126 else if (TREE_CODE (decl) == CONSTRUCTOR) 5127 { 5128 if ((shlib && reloc) 5129 || TREE_SIDE_EFFECTS (decl) 5130 || ! TREE_CONSTANT (decl)) 5131 ret = SECCAT_DATA; 5132 else 5133 ret = SECCAT_RODATA; 5134 } 5135 else 5136 ret = SECCAT_RODATA; 5137 5138 /* There are no read-only thread-local sections. */ 5139 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl)) 5140 { 5141 if (ret == SECCAT_BSS) 5142 ret = SECCAT_TBSS; 5143 else 5144 ret = SECCAT_TDATA; 5145 } 5146 5147 /* If the target uses small data sections, select it. */ 5148 else if ((*targetm.in_small_data_p) (decl)) 5149 { 5150 if (ret == SECCAT_BSS) 5151 ret = SECCAT_SBSS; 5152 else if (targetm.have_srodata_section && ret == SECCAT_RODATA) 5153 ret = SECCAT_SRODATA; 5154 else 5155 ret = SECCAT_SDATA; 5156 } 5157 5158 return ret; 5159} 5160 5161bool 5162decl_readonly_section (decl, reloc) 5163 tree decl; 5164 int reloc; 5165{ 5166 return decl_readonly_section_1 (decl, reloc, flag_pic); 5167} 5168 5169bool 5170decl_readonly_section_1 (decl, reloc, shlib) 5171 tree decl; 5172 int reloc; 5173 int shlib; 5174{ 5175 switch (categorize_decl_for_section (decl, reloc, shlib)) 5176 { 5177 case SECCAT_RODATA: 5178 case SECCAT_RODATA_MERGE_STR: 5179 case SECCAT_RODATA_MERGE_STR_INIT: 5180 case SECCAT_RODATA_MERGE_CONST: 5181 case SECCAT_SRODATA: 5182 return true; 5183 break; 5184 default: 5185 return false; 5186 break; 5187 } 5188} 5189 5190/* Select a section based on the above categorization. */ 5191 5192void 5193default_elf_select_section (decl, reloc, align) 5194 tree decl; 5195 int reloc; 5196 unsigned HOST_WIDE_INT align; 5197{ 5198 default_elf_select_section_1 (decl, reloc, align, flag_pic); 5199} 5200 5201void 5202default_elf_select_section_1 (decl, reloc, align, shlib) 5203 tree decl; 5204 int reloc; 5205 unsigned HOST_WIDE_INT align; 5206 int shlib; 5207{ 5208 switch (categorize_decl_for_section (decl, reloc, shlib)) 5209 { 5210 case SECCAT_TEXT: 5211 /* We're not supposed to be called on FUNCTION_DECLs. */ 5212 abort (); 5213 case SECCAT_RODATA: 5214 readonly_data_section (); 5215 break; 5216 case SECCAT_RODATA_MERGE_STR: 5217 mergeable_string_section (decl, align, 0); 5218 break; 5219 case SECCAT_RODATA_MERGE_STR_INIT: 5220 mergeable_string_section (DECL_INITIAL (decl), align, 0); 5221 break; 5222 case SECCAT_RODATA_MERGE_CONST: 5223 mergeable_constant_section (DECL_MODE (decl), align, 0); 5224 break; 5225 case SECCAT_SRODATA: 5226 named_section (NULL_TREE, ".sdata2", reloc); 5227 break; 5228 case SECCAT_DATA: 5229 data_section (); 5230 break; 5231 case SECCAT_DATA_REL: 5232 named_section (NULL_TREE, ".data.rel", reloc); 5233 break; 5234 case SECCAT_DATA_REL_LOCAL: 5235 named_section (NULL_TREE, ".data.rel.local", reloc); 5236 break; 5237 case SECCAT_DATA_REL_RO: 5238 named_section (NULL_TREE, ".data.rel.ro", reloc); 5239 break; 5240 case SECCAT_DATA_REL_RO_LOCAL: 5241 named_section (NULL_TREE, ".data.rel.ro.local", reloc); 5242 break; 5243 case SECCAT_SDATA: 5244 named_section (NULL_TREE, ".sdata", reloc); 5245 break; 5246 case SECCAT_TDATA: 5247 named_section (NULL_TREE, ".tdata", reloc); 5248 break; 5249 case SECCAT_BSS: 5250#ifdef BSS_SECTION_ASM_OP 5251 bss_section (); 5252#else 5253 named_section (NULL_TREE, ".bss", reloc); 5254#endif 5255 break; 5256 case SECCAT_SBSS: 5257 named_section (NULL_TREE, ".sbss", reloc); 5258 break; 5259 case SECCAT_TBSS: 5260 named_section (NULL_TREE, ".tbss", reloc); 5261 break; 5262 default: 5263 abort (); 5264 } 5265} 5266 5267/* Construct a unique section name based on the decl name and the 5268 categorization performed above. */ 5269 5270void 5271default_unique_section (decl, reloc) 5272 tree decl; 5273 int reloc; 5274{ 5275 default_unique_section_1 (decl, reloc, flag_pic); 5276} 5277 5278void 5279default_unique_section_1 (decl, reloc, shlib) 5280 tree decl; 5281 int reloc; 5282 int shlib; 5283{ 5284 bool one_only = DECL_ONE_ONLY (decl); 5285 const char *prefix, *name; 5286 size_t nlen, plen; 5287 char *string; 5288 5289 switch (categorize_decl_for_section (decl, reloc, shlib)) 5290 { 5291 case SECCAT_TEXT: 5292 prefix = one_only ? ".gnu.linkonce.t." : ".text."; 5293 break; 5294 case SECCAT_RODATA: 5295 case SECCAT_RODATA_MERGE_STR: 5296 case SECCAT_RODATA_MERGE_STR_INIT: 5297 case SECCAT_RODATA_MERGE_CONST: 5298 prefix = one_only ? ".gnu.linkonce.r." : ".rodata."; 5299 break; 5300 case SECCAT_SRODATA: 5301 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2."; 5302 break; 5303 case SECCAT_DATA: 5304 case SECCAT_DATA_REL: 5305 case SECCAT_DATA_REL_LOCAL: 5306 case SECCAT_DATA_REL_RO: 5307 case SECCAT_DATA_REL_RO_LOCAL: 5308 prefix = one_only ? ".gnu.linkonce.d." : ".data."; 5309 break; 5310 case SECCAT_SDATA: 5311 prefix = one_only ? ".gnu.linkonce.s." : ".sdata."; 5312 break; 5313 case SECCAT_BSS: 5314 prefix = one_only ? ".gnu.linkonce.b." : ".bss."; 5315 break; 5316 case SECCAT_SBSS: 5317 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss."; 5318 break; 5319 case SECCAT_TDATA: 5320 prefix = one_only ? ".gnu.linkonce.td." : ".tdata."; 5321 break; 5322 case SECCAT_TBSS: 5323 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss."; 5324 break; 5325 default: 5326 abort (); 5327 } 5328 plen = strlen (prefix); 5329 5330 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 5331 name = (* targetm.strip_name_encoding) (name); 5332 nlen = strlen (name); 5333 5334 string = alloca (nlen + plen + 1); 5335 memcpy (string, prefix, plen); 5336 memcpy (string + plen, name, nlen + 1); 5337 5338 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string); 5339} 5340 5341void 5342default_select_rtx_section (mode, x, align) 5343 enum machine_mode mode ATTRIBUTE_UNUSED; 5344 rtx x; 5345 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED; 5346{ 5347 if (flag_pic) 5348 switch (GET_CODE (x)) 5349 { 5350 case CONST: 5351 case SYMBOL_REF: 5352 case LABEL_REF: 5353 data_section (); 5354 return; 5355 5356 default: 5357 break; 5358 } 5359 5360 readonly_data_section (); 5361} 5362 5363void 5364default_elf_select_rtx_section (mode, x, align) 5365 enum machine_mode mode; 5366 rtx x; 5367 unsigned HOST_WIDE_INT align; 5368{ 5369 /* ??? Handle small data here somehow. */ 5370 5371 if (flag_pic) 5372 switch (GET_CODE (x)) 5373 { 5374 case CONST: 5375 case SYMBOL_REF: 5376 named_section (NULL_TREE, ".data.rel.ro", 3); 5377 return; 5378 5379 case LABEL_REF: 5380 named_section (NULL_TREE, ".data.rel.ro.local", 1); 5381 return; 5382 5383 default: 5384 break; 5385 } 5386 5387 mergeable_constant_section (mode, align, 0); 5388} 5389 5390/* By default, we do nothing for encode_section_info, so we need not 5391 do anything but discard the '*' marker. */ 5392 5393const char * 5394default_strip_name_encoding (str) 5395 const char *str; 5396{ 5397 return str + (*str == '*'); 5398} 5399 5400/* Assume ELF-ish defaults, since that's pretty much the most liberal 5401 wrt cross-module name binding. */ 5402 5403bool 5404default_binds_local_p (exp) 5405 tree exp; 5406{ 5407 return default_binds_local_p_1 (exp, flag_pic); 5408} 5409 5410bool 5411default_binds_local_p_1 (exp, shlib) 5412 tree exp; 5413 int shlib; 5414{ 5415 bool local_p; 5416 5417 /* A non-decl is an entry in the constant pool. */ 5418 if (!DECL_P (exp)) 5419 local_p = true; 5420 /* Static variables are always local. */ 5421 else if (! TREE_PUBLIC (exp)) 5422 local_p = true; 5423 /* A variable is local if the user tells us so. */ 5424 else if (decl_visibility (exp) != VISIBILITY_DEFAULT) 5425 local_p = true; 5426 /* Otherwise, variables defined outside this object may not be local. */ 5427 else if (DECL_EXTERNAL (exp)) 5428 local_p = false; 5429 /* Linkonce and weak data are never local. */ 5430 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp)) 5431 local_p = false; 5432 /* If PIC, then assume that any global name can be overridden by 5433 symbols resolved from other modules. */ 5434 else if (shlib) 5435 local_p = false; 5436 /* Uninitialized COMMON variable may be unified with symbols 5437 resolved from other modules. */ 5438 else if (DECL_COMMON (exp) 5439 && (DECL_INITIAL (exp) == NULL 5440 || DECL_INITIAL (exp) == error_mark_node)) 5441 local_p = false; 5442 /* Otherwise we're left with initialized (or non-common) global data 5443 which is of necessity defined locally. */ 5444 else 5445 local_p = true; 5446 5447 return local_p; 5448} 5449 5450/* Default function to output code that will globalize a label. A 5451 target must define GLOBAL_ASM_OP or provide it's own function to 5452 globalize a label. */ 5453#ifdef GLOBAL_ASM_OP 5454void 5455default_globalize_label (stream, name) 5456 FILE * stream; 5457 const char *name; 5458{ 5459 fputs (GLOBAL_ASM_OP, stream); 5460 assemble_name (stream, name); 5461 putc ('\n', stream); 5462} 5463#endif /* GLOBAL_ASM_OP */ 5464 5465#include "gt-varasm.h" 5466